diff --git a/MANIFEST.SKIP b/MANIFEST.SKIP
index 4e602ed87..4259ac3df 100644
--- a/MANIFEST.SKIP
+++ b/MANIFEST.SKIP
@@ -16,6 +16,8 @@
 /obj_dir/
 /obj_dbg/
 /obj_opt/
+/obj_vlt/
+/obj_dist/
 /INCA_libs/
 /cov_work/
 /logs/
diff --git a/bin/verilator b/bin/verilator
index 3a2a81734..5465f6265 100755
--- a/bin/verilator
+++ b/bin/verilator
@@ -545,7 +545,7 @@ functions to avoid error C1061.
 
 =back
 
-=item --converge-limit <loops>
+=item --converge-limit I<loops>
 
 Rarely needed.  Specifies the maximum number of runtime iterations before
 creating a model failed to converge error.  Defaults to 100.
@@ -654,9 +654,9 @@ when Verilating large models in --debug mode.
 Outside of --debug mode, AstNode's should never be leaked and this option
 has no effect.
 
-=item --debugi <level>
+=item --debugi I<level>
 
-=item --debugi-<srcfile> <level>
+=item --debugi-I<srcfile> I<level>
 
 Rarely needed - for developer use.  Set internal debugging level globally
 to the specified debug level (1-10) or set the specified Verilator source
@@ -698,9 +698,9 @@ the Verilator Internals manual.  --dump-tree is enabled automatically with
 --debug, so "--debug --no-dump-tree" may be useful if the dump files are
 large and not desired.
 
-=item --dump-treei <level>
+=item --dump-treei I<level>
 
-=item --dump-treei-<srcfile> <level>
+=item --dump-treei-I<srcfile> I<level>
 
 Rarely needed - for developer use.  Set internal tree dumping level
 globally to a specific dumping level or set the specified Verilator source
@@ -714,7 +714,7 @@ Preprocess the source code, but do not compile, as with 'gcc -E'.  Output
 is written to standard out.  Beware of enabling debugging messages, as they
 will also go to standard out.
 
-=item --error-limit <value>
+=item --error-limit I<value>
 
 After this number of errors or warnings are encountered, exit.  Defaults to
 50.
@@ -741,7 +741,7 @@ The file may contain // comments which are ignored to the end of the line.
 Any $VAR, $(VAR), or ${VAR} will be replaced with the specified environment
 variable.
 
-=item -FI <file>
+=item -FI I<file>
 
 Force include of the specified C++ header file.  All generated C++ files
 will insert a #include of the specified file before any other includes. The
@@ -773,7 +773,7 @@ Double literals must contain a dot (.) and/or an exponent (e).
 
 =item Strings
 
-String must in double quotes ("). On the command line it is required to escape
+String must in double quotes (""). On the command line it is required to escape
 them properly, e.g. as -GSTR="\"My String\"" or -GSTR='"My String"'.
 
 =back
@@ -899,7 +899,7 @@ otherwise manually create the Mdir before calling Verilator.
 Specifies the name to prepend to all lower level classes.  Defaults to
 the same as --prefix.
 
-=item --no-clk <signal-name>
+=item --no-clk I<signal-name>
 
 Prevent the specified signal from being marked as clock. See C<--clk>.
 
@@ -958,7 +958,7 @@ disables an optimization, an upper case letter enables it.  This is
 intended for debugging use only; see the source code for version-dependent
 mappings of optimizations to -O letters.
 
-=item -o <executable>
+=item -o I<executable>
 
 Specify the name for the final executable built if using --exe.  Defaults
 to the --prefix if not specified.
diff --git a/test_regress/.gitignore b/test_regress/.gitignore
index 105d838e2..78bd52977 100644
--- a/test_regress/.gitignore
+++ b/test_regress/.gitignore
@@ -1,5 +1,6 @@
 *.old
 obj_dir
+obj_*
 vcs.key
 csrc
 cov_work
diff --git a/test_regress/Makefile b/test_regress/Makefile
index 34cc1a5ee..84ed472bb 100644
--- a/test_regress/Makefile
+++ b/test_regress/Makefile
@@ -33,8 +33,6 @@ ifneq ($(NC_ROOT),)
 #PRODUCTS += --nc
 endif
 
-PRODUCTS += --vlt
-
 # Run tests in parallel.  Requires Parallel::Forker to be installed.
 ifeq ($(CFG_WITH_LONGTESTS),yes)
  DRIVER_FLAGS += -j 0
@@ -46,7 +44,7 @@ endif
 
 .PHONY: test
 test:
-	$(PERL) driver.pl $(DRIVER_FLAGS) $(PRODUCTS)
+	$(PERL) driver.pl $(DRIVER_FLAGS) --vlt --dist
 
 ######################################################################
 
@@ -82,4 +80,4 @@ print-cxx-version:
 ######################################################################
 maintainer-copy::
 clean mostlyclean distclean maintainer-clean::
-	-rm -rf obj_dir simv* simx* csrc cov_work INCA_libs *.log *.key logs vc_hdrs.h
+	-rm -rf obj_* simv* simx* csrc cov_work INCA_libs *.log *.key logs vc_hdrs.h
diff --git a/test_regress/Makefile_obj b/test_regress/Makefile_obj
index ce202f7cb..1536a77e7 100644
--- a/test_regress/Makefile_obj
+++ b/test_regress/Makefile_obj
@@ -34,6 +34,7 @@ CPPFLAGS += -DVL_DEBUG=1
 #CPPFLAGS += -D_GLIBCXX_DEBUG
 
 # Needed by tracing routines
+CPPFLAGS += -DTEST_OBJ_DIR=$(TEST_OBJ_DIR)
 CPPFLAGS += -DVM_PREFIX=$(VM_PREFIX)
 CPPFLAGS += -DVM_PREFIX_INCLUDE="<$(VM_PREFIX).h>"
 CPPFLAGS += $(CPPFLAGS_DRIVER)
diff --git a/test_regress/driver.pl b/test_regress/driver.pl
index d05c6aa96..d8ec59486 100755
--- a/test_regress/driver.pl
+++ b/test_regress/driver.pl
@@ -33,6 +33,18 @@ $SIG{TERM} = sub { $Fork->kill_tree_all('TERM') if $Fork; die "Quitting...\n"; }
 
 #======================================================================
 
+# Map of all scenarios, with the names used to enable them
+our %All_Scenarios
+    = (dist  => [             "dist"],
+       atsim => ["simulator", "atsim"],
+       ghdl  => ["simulator", "ghdl"],
+       iv    => ["simulator", "iv"],
+       ms    => ["simulator", "ms"],
+       nc    => ["simulator", "nc"],
+       vcs   => ["simulator", "vcs"],
+       vlt   => ["simulator", "vlt_all", "vlt"],
+    );
+
 #======================================================================
 # main
 
@@ -44,23 +56,18 @@ our @Orig_ARGV_Sw;  foreach (@Orig_ARGV) { push @Orig_ARGV_Sw, $_ if /^-/ && !/^
 our $Start = time();
 
 $Debug = 0;
-my $opt_atsim;
 my $opt_benchmark;
 my @opt_tests;
+my $opt_dist;
 my $opt_gdb;
 my $opt_gdbbt;
 my $opt_gdbsim;
-my $opt_ghdl;
-my $opt_iv;
 my $opt_jobs = 1;
-my $opt_ms;
-my $opt_nc;
 my $opt_optimize;
+my %opt_scenarios;
 my $opt_site;
 my $opt_stop;
 my $opt_trace;
-my $opt_vlt;
-my $opt_vcs;
 my $opt_verbose;
 my $Opt_Verilated_Debug;
 our $Opt_Unsupported;
@@ -69,35 +76,35 @@ our @Opt_Driver_Verilator_Flags;
 
 Getopt::Long::config ("pass_through");
 if (! GetOptions (
-		  "benchmark:i" => sub { $opt_benchmark = $_[1] ? $_[1] : 1; },
-		  "debug"	=> \&debug,
-	  	  #debugi	   see parameter()
-		  "atsim|athdl!"=> \$opt_atsim,
-		  "gdb!"	=> \$opt_gdb,
-		  "gdbbt!"	=> \$opt_gdbbt,
-		  "gdbsim!"	=> \$opt_gdbsim,
-		  "ghdl!"	=> \$opt_ghdl,
-		  "golden!"	=> sub { $ENV{HARNESS_UPDATE_GOLDEN} = 1; },
-		  "help"	=> \&usage,
-		  "iverilog!"	=> \$opt_iv,
-		  "j=i"		=> \$opt_jobs,
-		  "ms!"		=> \$opt_ms,
-		  "nc!"		=> \$opt_nc,
-		  "optimize:s"	=> \$opt_optimize,
-		  "site!"	=> \$opt_site,
-		  "stop!"	=> \$opt_stop,
-		  "trace!"	=> \$opt_trace,
-	  	  "unsupported!"=> \$Opt_Unsupported,
-		  "v3!"		=> \$opt_vlt,  # Old
-		  "vl!"		=> \$opt_vlt,  # Old
-		  "vlt!"	=> \$opt_vlt,
-		  "vcs!"	=> \$opt_vcs,
-		  "verbose!"	=> \$opt_verbose,
-		  "verilation!"		=> \$Opt_Verilation,  # Undocumented debugging
-		  "verilated_debug!"	=> \$Opt_Verilated_Debug,
-	  	  #W		   see parameter()
-		  "<>"		=> \&parameter,
-		  )) {
+          "benchmark:i" => sub { $opt_benchmark = $_[1] ? $_[1] : 1; },
+          "debug"       => \&debug,
+          #debugi          see parameter()
+          "gdb!"        => \$opt_gdb,
+          "gdbbt!"      => \$opt_gdbbt,
+          "gdbsim!"     => \$opt_gdbsim,
+          "golden!"     => sub { $ENV{HARNESS_UPDATE_GOLDEN} = 1; },
+          "help"        => \&usage,
+          "j=i"         => \$opt_jobs,
+          "optimize:s"  => \$opt_optimize,
+          "site!"       => \$opt_site,
+          "stop!"       => \$opt_stop,
+          "trace!"      => \$opt_trace,
+          "unsupported!"=> \$Opt_Unsupported,
+          "verbose!"    => \$opt_verbose,
+          "verilation!"         => \$Opt_Verilation,  # Undocumented debugging
+          "verilated_debug!"    => \$Opt_Verilated_Debug,
+          #W               see parameter()
+          # Scenarios
+          "atsim|athdl!"=> sub { $opt_scenarios{atsim} = $_[1]; },
+          "dist!"       => sub { $opt_scenarios{dist} = $_[1]; },
+          "ghdl!"       => sub { $opt_scenarios{ghdl} = $_[1]; },
+          "iverilog!"   => sub { $opt_scenarios{iverilog} = $_[1]; },
+          "ms!"         => sub { $opt_scenarios{ms} = $_[1]; },
+          "nc!"         => sub { $opt_scenarios{nc} = $_[1]; },
+          "vlt!"        => sub { $opt_scenarios{vlt} = $_[1]; },
+          "vcs!"        => sub { $opt_scenarios{vcs} = $_[1]; },
+          "<>"          => \&parameter,
+    )) {
     die "%Error: Bad usage, try '$0 --help'\n";
 }
 
@@ -105,8 +112,9 @@ $opt_jobs = calc_jobs() if defined $opt_jobs && $opt_jobs==0;
 
 $Fork->max_proc($opt_jobs);
 
-if (!$opt_atsim && !$opt_ghdl && !$opt_iv && !$opt_vcs && !$opt_ms && !$opt_nc && !$opt_vlt) {
-    $opt_vlt = 1;
+if ((scalar keys %opt_scenarios) < 1) {
+    $opt_scenarios{dist} = 1;
+    $opt_scenarios{vlt} = 1;
 }
 
 our @Test_Dirs = "t";
@@ -128,20 +136,17 @@ if ($#opt_tests>=2 && $opt_jobs>=2) {
     open(STDIN,  "+>/dev/null");
 }
 
-mkdir "obj_dir";
 
-our $Log_Filename = "obj_dir/driver_".strftime("%Y%m%d_%H%M%S.log", localtime);
+mkdir "obj_dist";
+our $Log_Filename = "obj_dist/driver_".strftime("%Y%m%d_%H%M%S.log", localtime);
 my $LeftCnt=0; my $OkCnt=0; my $FailCnt=0; my $SkipCnt=0; my $UnsupCnt=0;
 my @fails;
 
 foreach my $testpl (@opt_tests) {
-    one_test(pl_filename => $testpl, atsim=>1) if $opt_atsim;
-    one_test(pl_filename => $testpl, ghdl=>1) if $opt_ghdl;
-    one_test(pl_filename => $testpl, iv=>1) if $opt_iv;
-    one_test(pl_filename => $testpl, ms=>1) if $opt_ms;
-    one_test(pl_filename => $testpl, nc=>1) if $opt_nc;
-    one_test(pl_filename => $testpl, vcs=>1) if $opt_vcs;
-    one_test(pl_filename => $testpl, vlt=>1, 'v3'=>1) if $opt_vlt;
+    foreach my $scenario (sort keys %opt_scenarios) {
+        next if !$opt_scenarios{$scenario};
+        one_test(pl_filename => $testpl, $scenario=>1);
+    }
 }
 
 $Fork->wait_all();   # Wait for all children to finish
@@ -159,25 +164,18 @@ sub one_test {
 	     my $test = VTest->new(@params);
 	     $test->oprint("="x50,"\n");
 	     unlink $test->{status_filename};
-	     $test->prep;
-	     $test->read;
-	     if ($test->ok) {
-		 $test->oprint("Test PASSED\n");
-	     } elsif ($test->skips && !$test->errors) {
-		 $test->oprint("%Skip: $test->{skips}\n");
-	     } elsif ($test->unsupporteds && !$test->errors) {
-		 $test->oprint("%Unsupported: $test->{unsupporteds}\n");
-	     } else {
-		 $test->error("Missing ok\n") if !$test->errors;
-		 $test->oprint("%Error: $test->{errors}\n");
-	     }
-	     $test->write_status;
+             $test->_prep;
+             $test->_read;
+             # Don't put anything other than _exit after _read,
+             # as may call _exit via another path
+             $test->_exit;
 	 },
 	 run_on_finish => sub {
 	     my $test = VTest->new(@params);
-	     $test->read_status;
+             $test->_read_status;
 	     if ($test->ok) {
 		 $OkCnt++;
+             } elsif ($test->scenario_off && !$test->errors) {
 	     } elsif ($test->skips && !$test->errors) {
 		 $SkipCnt++;
 	     } elsif ($test->unsupporteds && !$test->errors) {
@@ -187,7 +185,9 @@ sub one_test {
 		 my $j = ($opt_jobs>1?" -j":"");
 		 push @fails, ("\t#".$test->soprint("%Error: $test->{errors}\n")
 			       ."\t\tmake$j && test_regress/"
-			       .$test->{pl_filename}." ".join(' ',@Orig_ARGV_Sw)."\n");
+                               .$test->{pl_filename}
+                               ." ".join(' ', _args_scenario())
+                               ." --".$test->{scenario}."\n");
 		 $FailCnt++;
 		 report(\@fails, $Log_Filename);
 		 my $other = "";
@@ -278,6 +278,21 @@ sub report {
 	       int($delta/60),$delta%60);
 }
 
+sub _args_scenario {
+    # Return command line with scenarios stripped
+    my @out;
+  arg:
+    foreach my $arg (@Orig_ARGV_Sw) {
+        foreach my $allsc (keys %All_Scenarios) {
+            foreach my $allscarg (@{$All_Scenarios{$allsc}}) {
+                next arg if ("--$allscarg" eq $arg);
+            }
+        }
+        push @out, $arg;
+    }
+    return @out;
+}
+
 #######################################################################
 #######################################################################
 #######################################################################
@@ -299,18 +314,19 @@ sub new {
 
     $self->{name} ||= $2 if $self->{pl_filename} =~ m!^(.*/)?([^/]*)\.pl$!;
 
-    $self->{mode} = "";
-    $self->{mode} ||= "atsim" if $self->{atsim};
-    $self->{mode} ||= "ghdl" if $self->{ghdl};
-    $self->{mode} ||= "vcs" if $self->{vcs};
-    $self->{mode} ||= "vlt" if $self->{vlt};
-    $self->{mode} ||= "nc" if $self->{nc};
-    $self->{mode} ||= "ms" if $self->{ms};
-    $self->{mode} ||= "iv" if $self->{iv};
+    $self->{scenario} = "";
+    $self->{scenario} ||= "dist" if $self->{dist};
+    $self->{scenario} ||= "atsim" if $self->{atsim};
+    $self->{scenario} ||= "ghdl" if $self->{ghdl};
+    $self->{scenario} ||= "vcs" if $self->{vcs};
+    $self->{scenario} ||= "vlt" if $self->{vlt};
+    $self->{scenario} ||= "nc" if $self->{nc};
+    $self->{scenario} ||= "ms" if $self->{ms};
+    $self->{scenario} ||= "iv" if $self->{iv};
 
     # For backward compatibility, the verilator tests have no prefix
-    $self->{obj_dir} ||= ("obj_dir/".($self->{mode} eq 'vlt' ? "" : $self->{mode}."_")
-			  ."$self->{name}");
+    mkdir "obj_$self->{scenario}";
+    $self->{obj_dir} ||= ("obj_$self->{scenario}/$self->{name}");
 
     foreach my $dir (@::Test_Dirs) {
 	# t_dir used both absolutely and under obj_dir
@@ -339,6 +355,7 @@ sub new {
 	v_flags => [split(/\s+/,(" -f input.vc "
 				 .($self->{t_dir} !~ m!/test_regress!  # Don't include standard dir, only site's
 				   ? " +incdir+$self->{t_dir} -y $self->{t_dir}" : "")
+                                 . " +define+TEST_OBJ_DIR=$self->{obj_dir}"
 				 .($opt_verbose ? " +define+TEST_VERBOSE=1":"")
 				 .($opt_benchmark ? " +define+TEST_BENCHMARK=$opt_benchmark":"")
 				 .($opt_trace ? " +define+WAVES=1":"")
@@ -425,46 +442,82 @@ sub new {
 }
 
 sub soprint {
-    my $self = shift;
-    my $str = "$self->{mode}/$self->{name}: ".join('',@_);
+    my $self = (ref $_[0] ? shift : $Self);
+    my $str = "$self->{scenario}/$self->{name}: ".join('',@_);
     $str =~ s/\n\n+$/\n/s;
     return $str;
 }
 
 sub oprint {
-    my $self = shift;
+    my $self = (ref $_[0] ? shift : $Self);
     print $self->soprint(@_);
 }
 
 sub error {
-    my $self = shift;
+    my $self = (ref $_[0] ? shift : $Self);
     my $msg = join('',@_);
-    warn "%Warning: $self->{mode}/$self->{name}: ".$msg."\n";
+    # Called from tests as: error("Reason message"[, ...]);
+    warn "%Warning: $self->{scenario}/$self->{name}: ".$msg."\n";
     $self->{errors} ||= $msg;
 }
 
 sub skip {
-    my $self = shift;
+    my $self = (ref $_[0] ? shift : $Self);
     my $msg = join('',@_);
-    warn "%Skip: $self->{mode}/$self->{name}: ".$msg."\n";
+    # Called from tests as: skip("Reason message"[, ...]);
+    warn "-Skip: $self->{scenario}/$self->{name}: ".$msg."\n";
     $self->{skips} ||= "Skip: ".$msg;
 }
 
 sub unsupported {
-    my $self = shift;
+    my $self = (ref $_[0] ? shift : $Self);
     my $msg = join('',@_);
-    warn "%Unsupported: $self->{mode}/$self->{name}: ".$msg."\n";
+    # Called from tests as: unsupported("Reason message"[, ...]);
+    warn "-Unsupported: $self->{scenario}/$self->{name}: ".$msg."\n";
     if (!$::Opt_Unsupported) {
 	$self->{unsupporteds} ||= "Unsupported: ".$msg;
     }
 }
 
-sub prep {
+sub scenarios {
+    my $self = (ref $_[0] ? shift : $Self);
+    my %params = (@_);
+    # Called from tests as: scenarios(...);
+    # to specify which scenarios this test runs under.
+    #  Where ... is one cases listed in All_Scenarios
+    if ((scalar keys %params) < 1) {
+        $params{simulators} = 1;
+    }
+    my %enabled_scenarios;
+    foreach my $scenario (keys %params) {
+        my $value = $params{$scenario};
+        my $hit = 0;
+        foreach my $allsc (keys %All_Scenarios) {
+            foreach my $allscarg (@{$All_Scenarios{$allsc}}) {
+                if ($scenario eq $allscarg) {
+                    $hit = 1;
+                    $enabled_scenarios{$allsc} = 1;
+                }
+            }
+        }
+        if (!$hit) {
+            $self->error("scenarios('$scenario' => ...) has unknown scenario '$scenario',");
+        }
+    }
+
+    if (!$enabled_scenarios{$self->{scenario}}) {
+        $self->skip("scenario '$self->{scenario}' not enabled for test");
+        $self->{scenario_off} ||= 1;
+        $self->_exit();
+    }
+}
+
+sub _prep {
     my $self = shift;
     mkdir $self->{obj_dir};  # Ok if already exists
 }
 
-sub read {
+sub _read {
     my $self = shift;
     # Read the control file
     (-r $self->{pl_filename})
@@ -474,7 +527,23 @@ sub read {
     require $self->{pl_filename};
 }
 
-sub write_status {
+sub _exit {
+    my $self = shift;
+    if ($self->ok) {
+        $self->oprint("Self PASSED\n");
+    } elsif ($self->skips && !$self->errors) {
+        $self->oprint("%Skip: $self->{skips}\n");
+    } elsif ($self->unsupporteds && !$self->errors) {
+        $self->oprint("%Unsupported: $self->{unsupporteds}\n");
+    } else {
+        $self->error("Missing ok\n") if !$self->errors;
+        $self->oprint("%Error: $self->{errors}\n");
+    }
+    $self->_write_status;
+    exit(0);
+}
+
+sub _write_status {
     my $self = shift;
     my $filename = $self->{status_filename};
     my $fh = IO::File->new(">$filename") or die "%Error: $! $filename,";
@@ -483,7 +552,7 @@ sub write_status {
     $fh->close();
 }
 
-sub read_status {
+sub _read_status {
     my $self = shift;
     my $filename = $self->{status_filename};
     use vars qw($VAR1);
@@ -686,6 +755,7 @@ sub compile {
                              "-C ".$self->{obj_dir},
                              "-f ".getcwd()."/Makefile_obj",
 			      "VM_PREFIX=$self->{VM_PREFIX}",
+                              "TEST_OBJ_DIR=$self->{obj_dir}",
 			      "CPPFLAGS_DRIVER=-D".uc($self->{name}),
 			      ($opt_verbose ? "CPPFLAGS_DRIVER2=-DTEST_VERBOSE=1":""),
 			      ($param{make_main}?"":"MAKE_MAIN=0"),
@@ -696,7 +766,7 @@ sub compile {
 	}
     }
     else {
-	$self->error("No compile step for this simulator");
+        $self->error("No compile step defined for '$self->{scenario}' scenario");
     }
 
     if ($param{make_pli}) {
@@ -875,6 +945,11 @@ sub errors {
     return $self->{errors};
 }
 
+sub scenario_off {
+    my $self = (ref $_[0]? shift : $Self);
+    return $self->{scenario_off};
+}
+
 sub skips {
     my $self = (ref $_[0]? shift : $Self);
     return $self->{skips};
@@ -1529,8 +1604,8 @@ sub cxx_version {
 
 our $_Cfg_With_Threaded;
 sub cfg_with_threaded {
-    my $out = `make -f ../Makefile print-cfg-with-threaded`;
-    return ($out =~ /yes/i) ? 1:0;
+    $_Cfg_With_Threaded ||= `make -f ../Makefile print-cfg-with-threaded`;
+    return ($_Cfg_With_Threaded =~ /yes/i) ? 1:0;
 }
 
 sub file_grep_not {
@@ -1844,10 +1919,6 @@ not matter. This makes it easier to extend or modify the test in future.
 
 =over 4
 
-=item --atsim
-
-Run using ATSIM simulator.
-
 =item --benchmark [<cycles>]
 
 Show execution times of each step.  If an optional number is given,
@@ -1885,10 +1956,6 @@ print backtrace information.  Requires --debug.
 
 Run Verilator generated executable under the debugger.
 
-=item --ghdl
-
-Run using GHDL simulator.
-
 =item --golden
 
 Update golden files, equivalent to setting HARNESS_UPDATE_GOLDEN=1.
@@ -1897,23 +1964,11 @@ Update golden files, equivalent to setting HARNESS_UPDATE_GOLDEN=1.
 
 Displays this message and program version and exits.
 
-=item --iverilog
-
-Run using Icarus Verilog simulator.
-
 =item --j #
 
 Run number of parallel tests, or 0 to determine the count based on the
 number of cores installed.  Requires Perl's Parallel::Forker package.
 
-=item --ms
-
-Run using ModelSim simulator.
-
-=item --nc
-
-Run using Cadence NC-Verilog simulator.
-
 =item --optimize
 
 Randomly turn on/off different optimizations.  With specific flags,
@@ -1935,18 +1990,52 @@ Set the simulator specific flags to request waveform tracing.
 
 Run tests even if marked as unsupported.
 
-=item --vcs
-
-Run using Synopsys VCS simulator.
-
 =item --verbose
 
 Compile and run the test in verbose mode. This means C<TEST_VERBOSE> will
 be defined for the test (Verilog and any C++/SystemC wrapper).
 
+=back
+
+=head1 SCENARIO ARGUMENTS
+
+The following options control which simulator is used, and which tests are
+run.  Multiple flags may be used to run multiple simulators/scenarios
+simultaneously.
+
+=over 4
+
+=item --atsim
+
+Run ATSIM simulator tests.
+
+=item --dist
+
+Run simulator-agnostic distribution tests.
+
+=item --ghdl
+
+Run GHDL simulator tests.
+
+=item --iverilog
+
+Run Icarus Verilog simulator tests.
+
+=item --ms
+
+Run ModelSim simulator tests.
+
+=item --nc
+
+Run Cadence NC-Verilog simulator tests.
+
+=item --vcs
+
+Run Synopsys VCS simulator tests.
+
 =item --vlt
 
-Run using Verilator.  Defaults set unless another simulator is requested.
+Run Verilator tests.  Default unless another scenario flag is provided.
 
 =back
 
diff --git a/test_regress/t/bootstrap.pl b/test_regress/t/bootstrap.pl
index c910b407a..a057f813c 100755
--- a/test_regress/t/bootstrap.pl
+++ b/test_regress/t/bootstrap.pl
@@ -19,4 +19,4 @@ $ENV{PWD} = Cwd::getcwd();  # Else chdir leaves the .. which confuses later comm
 @args = map { s!.*test_regress/!!; $_; } @args;
 
 exec("./driver.pl", @args);
-die;
+die "$!, in exec";
diff --git a/test_regress/t/t_EXAMPLE.pl b/test_regress/t/t_EXAMPLE.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_EXAMPLE.pl
+++ b/test_regress/t/t_EXAMPLE.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_a_first_cc.pl b/test_regress/t/t_a_first_cc.pl
index db757b56d..3ec02ecfd 100755
--- a/test_regress/t/t_a_first_cc.pl
+++ b/test_regress/t/t_a_first_cc.pl
@@ -11,16 +11,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # after building so we make sure to run with --gdbbt, so if it dumps we'll
 # get a trace.
 
+scenarios(simulator => 1);
+
 $DEBUG_QUIET = "--debug --debugi 0 --gdbbt --no-dump-tree";
 
-$Self->run(cmd=>["perl", "../bin/verilator", $DEBUG_QUIET, "-V"]);
+run(cmd => ["perl", "../bin/verilator", $DEBUG_QUIET, "-V"]);
 
-compile (
+compile(
     verilator_flags2 => [$DEBUG_QUIET, "--trace"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_a_first_sc.pl b/test_regress/t/t_a_first_sc.pl
index 164c9122e..b09f932f0 100755
--- a/test_regress/t/t_a_first_sc.pl
+++ b/test_regress/t/t_a_first_sc.pl
@@ -11,16 +11,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # after building so we make sure to run with --gdbbt, so if it dumps we'll
 # get a trace.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_a_first_cc.v");
 
 $DEBUG_QUIET = "--debug --debugi 0 --gdbbt --no-dump-tree";
 
-compile (
+compile(
     verilator_flags2 => [$DEBUG_QUIET, "-sc --trace"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_altera_lpm_abs.pl b/test_regress/t/t_altera_lpm_abs.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_abs.pl
+++ b/test_regress/t/t_altera_lpm_abs.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_add_sub.pl b/test_regress/t/t_altera_lpm_add_sub.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_add_sub.pl
+++ b/test_regress/t/t_altera_lpm_add_sub.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_and.pl b/test_regress/t/t_altera_lpm_and.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_and.pl
+++ b/test_regress/t/t_altera_lpm_and.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_bustri.pl b/test_regress/t/t_altera_lpm_bustri.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_bustri.pl
+++ b/test_regress/t/t_altera_lpm_bustri.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_clshift.pl b/test_regress/t/t_altera_lpm_clshift.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_clshift.pl
+++ b/test_regress/t/t_altera_lpm_clshift.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_compare.pl b/test_regress/t/t_altera_lpm_compare.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_compare.pl
+++ b/test_regress/t/t_altera_lpm_compare.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_constant.pl b/test_regress/t/t_altera_lpm_constant.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_constant.pl
+++ b/test_regress/t/t_altera_lpm_constant.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_counter.pl b/test_regress/t/t_altera_lpm_counter.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_counter.pl
+++ b/test_regress/t/t_altera_lpm_counter.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_decode.pl b/test_regress/t/t_altera_lpm_decode.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_decode.pl
+++ b/test_regress/t/t_altera_lpm_decode.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_divide.pl b/test_regress/t/t_altera_lpm_divide.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_divide.pl
+++ b/test_regress/t/t_altera_lpm_divide.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_ff.pl b/test_regress/t/t_altera_lpm_ff.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_ff.pl
+++ b/test_regress/t/t_altera_lpm_ff.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_fifo.pl b/test_regress/t/t_altera_lpm_fifo.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_fifo.pl
+++ b/test_regress/t/t_altera_lpm_fifo.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_fifo_dc.pl b/test_regress/t/t_altera_lpm_fifo_dc.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_fifo_dc.pl
+++ b/test_regress/t/t_altera_lpm_fifo_dc.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_inv.pl b/test_regress/t/t_altera_lpm_inv.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_inv.pl
+++ b/test_regress/t/t_altera_lpm_inv.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_latch.pl b/test_regress/t/t_altera_lpm_latch.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_latch.pl
+++ b/test_regress/t/t_altera_lpm_latch.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_mult.pl b/test_regress/t/t_altera_lpm_mult.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_mult.pl
+++ b/test_regress/t/t_altera_lpm_mult.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_mux.pl b/test_regress/t/t_altera_lpm_mux.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_mux.pl
+++ b/test_regress/t/t_altera_lpm_mux.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_or.pl b/test_regress/t/t_altera_lpm_or.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_or.pl
+++ b/test_regress/t/t_altera_lpm_or.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_ram_dp.pl b/test_regress/t/t_altera_lpm_ram_dp.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_ram_dp.pl
+++ b/test_regress/t/t_altera_lpm_ram_dp.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_ram_dq.pl b/test_regress/t/t_altera_lpm_ram_dq.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_ram_dq.pl
+++ b/test_regress/t/t_altera_lpm_ram_dq.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_ram_io.pl b/test_regress/t/t_altera_lpm_ram_io.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_ram_io.pl
+++ b/test_regress/t/t_altera_lpm_ram_io.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_rom.pl b/test_regress/t/t_altera_lpm_rom.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_rom.pl
+++ b/test_regress/t/t_altera_lpm_rom.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_shiftreg.pl b/test_regress/t/t_altera_lpm_shiftreg.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_shiftreg.pl
+++ b/test_regress/t/t_altera_lpm_shiftreg.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_altera_lpm_xor.pl b/test_regress/t/t_altera_lpm_xor.pl
index 52a4f89f5..20782a400 100755
--- a/test_regress/t/t_altera_lpm_xor.pl
+++ b/test_regress/t/t_altera_lpm_xor.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_altera_lpm.v");
 (my $module = $Self->{name}) =~ s/.*t_altera_//;
 
-compile (
+compile(
     verilator_flags2 => ["--top-module ${module}"]
     );
 
diff --git a/test_regress/t/t_alw_combdly.pl b/test_regress/t/t_alw_combdly.pl
index 29bf04d49..b1acebe26 100755
--- a/test_regress/t/t_alw_combdly.pl
+++ b/test_regress/t/t_alw_combdly.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_alw_dly.pl b/test_regress/t/t_alw_dly.pl
index 2ca3a9b9a..a83c168ba 100755
--- a/test_regress/t/t_alw_dly.pl
+++ b/test_regress/t/t_alw_dly.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    verilator_flags2 => ["-Wno-CLKDATA"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ["-Wno-CLKDATA"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_alw_noreorder.pl b/test_regress/t/t_alw_noreorder.pl
old mode 100644
new mode 100755
index cce730af7..e7f37da92
--- a/test_regress/t/t_alw_noreorder.pl
+++ b/test_regress/t/t_alw_noreorder.pl
@@ -7,7 +7,7 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_alw_reorder.v");
 compile (
diff --git a/test_regress/t/t_alw_nosplit.pl b/test_regress/t/t_alw_nosplit.pl
old mode 100644
new mode 100755
index 2fcd2aee3..8ee968a0e
--- a/test_regress/t/t_alw_nosplit.pl
+++ b/test_regress/t/t_alw_nosplit.pl
@@ -7,6 +7,8 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 compile (
     verilator_flags2 => ["--stats"],
     );
diff --git a/test_regress/t/t_alw_reorder.pl b/test_regress/t/t_alw_reorder.pl
old mode 100644
new mode 100755
index 9d4beca3e..223be40a2
--- a/test_regress/t/t_alw_reorder.pl
+++ b/test_regress/t/t_alw_reorder.pl
@@ -7,7 +7,7 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 compile (
     verilator_flags2 => ["--stats"],
diff --git a/test_regress/t/t_alw_split.pl b/test_regress/t/t_alw_split.pl
index 63469761f..c78009c95 100755
--- a/test_regress/t/t_alw_split.pl
+++ b/test_regress/t/t_alw_split.pl
@@ -7,17 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ["--stats"],
-	 );
+scenarios(simulator => 1);
+
+compile(
+    verilator_flags2 => ["--stats"],
+    );
 
 if ($Self->{vlt}) {
     file_grep ($Self->{stats}, qr/Optimizations, Split always\s+(\d+)/i, 3);
 }
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_alw_split_rst.pl b/test_regress/t/t_alw_split_rst.pl
index 2fcd2aee3..5dbeceba1 100755
--- a/test_regress/t/t_alw_split_rst.pl
+++ b/test_regress/t/t_alw_split_rst.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--stats"],
     );
 
@@ -15,8 +17,8 @@ if ($Self->{vlt}) {
     file_grep ($Self->{stats}, qr/Optimizations, Split always\s+(\d+)/i, 0);
 }
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_alw_splitord.pl b/test_regress/t/t_alw_splitord.pl
index e858e241e..5dbeceba1 100755
--- a/test_regress/t/t_alw_splitord.pl
+++ b/test_regress/t/t_alw_splitord.pl
@@ -7,17 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ["--stats"],
-	 );
+scenarios(simulator => 1);
+
+compile(
+    verilator_flags2 => ["--stats"],
+    );
 
 if ($Self->{vlt}) {
     file_grep ($Self->{stats}, qr/Optimizations, Split always\s+(\d+)/i, 0);
 }
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_array_backw_index_bad.pl b/test_regress/t/t_array_backw_index_bad.pl
index ee69233a3..a4cdf3295 100755
--- a/test_regress/t/t_array_backw_index_bad.pl
+++ b/test_regress/t/t_array_backw_index_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    fails=>1,
-    expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 q{%Error: t/t_array_backw_index_bad.v:\d+: Slice selection '\[1:3\]' has backward indexing versus data type's '\[3:0\]'
 %Error: t/t_array_backw_index_bad.v:\d+: Slice selection '\[3:1\]' has backward indexing versus data type's '\[0:3\]'
 %Error: t/t_array_backw_index_bad.v:\d+: Slice selection index '\[4:3\]' outside data type's '\[3:0\]'
diff --git a/test_regress/t/t_array_compare.pl b/test_regress/t/t_array_compare.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_array_compare.pl
+++ b/test_regress/t/t_array_compare.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_array_interface.pl b/test_regress/t/t_array_interface.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_array_interface.pl
+++ b/test_regress/t/t_array_interface.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_array_interface_noinl.pl b/test_regress/t/t_array_interface_noinl.pl
index e5d1dc50a..1fa90dabe 100755
--- a/test_regress/t/t_array_interface_noinl.pl
+++ b/test_regress/t/t_array_interface_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_array_interface.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_array_packed_sysfunct.pl b/test_regress/t/t_array_packed_sysfunct.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_array_packed_sysfunct.pl
+++ b/test_regress/t/t_array_packed_sysfunct.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_array_packed_write_read.pl b/test_regress/t/t_array_packed_write_read.pl
index fe649af5b..928ac00f2 100755
--- a/test_regress/t/t_array_packed_write_read.pl
+++ b/test_regress/t/t_array_packed_write_read.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, bug446");
+scenarios(simulator => 1);
 
-compile (
-	 );
+$Self->{vlt} and unsupported("Verilator unsupported, bug446");
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_array_pattern_2d.pl b/test_regress/t/t_array_pattern_2d.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_array_pattern_2d.pl
+++ b/test_regress/t/t_array_pattern_2d.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_array_pattern_packed.pl b/test_regress/t/t_array_pattern_packed.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_array_pattern_packed.pl
+++ b/test_regress/t/t_array_pattern_packed.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_array_pattern_unpacked.pl b/test_regress/t/t_array_pattern_unpacked.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_array_pattern_unpacked.pl
+++ b/test_regress/t/t_array_pattern_unpacked.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_array_query.pl b/test_regress/t/t_array_query.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_array_query.pl
+++ b/test_regress/t/t_array_query.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_array_rev.pl b/test_regress/t/t_array_rev.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_array_rev.pl
+++ b/test_regress/t/t_array_rev.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_array_type_methods.pl b/test_regress/t/t_array_type_methods.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_array_type_methods.pl
+++ b/test_regress/t/t_array_type_methods.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_arraysel_wide.pl b/test_regress/t/t_arraysel_wide.pl
index 385b6a57e..5c448de7c 100755
--- a/test_regress/t/t_arraysel_wide.pl
+++ b/test_regress/t/t_arraysel_wide.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
 ok(1);
diff --git a/test_regress/t/t_assert_basic.pl b/test_regress/t/t_assert_basic.pl
index ef9866039..f97a8c4aa 100755
--- a/test_regress/t/t_assert_basic.pl
+++ b/test_regress/t/t_assert_basic.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ['--assert'],
-	 nc_flags2 => ['+assert'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    verilator_flags2 => ['--assert'],
+    nc_flags2 => ['+assert'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_assert_basic_cover.pl b/test_regress/t/t_assert_basic_cover.pl
index a14ea162d..a92304bcf 100755
--- a/test_regress/t/t_assert_basic_cover.pl
+++ b/test_regress/t/t_assert_basic_cover.pl
@@ -7,21 +7,23 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_assert_basic.v");
 
-compile (
-	 verilator_flags2 => ['--assert --cc --coverage-user'],
-	 );
+compile(
+    verilator_flags2 => ['--assert --cc --coverage-user'],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 #Needs work
 print "-Info:  NOT checking for coverage\n";
-#file_grep ($Self->{coverage_filename}, qr/t=>'psl_cover',o=>'cover',c=>2\);/);
-#file_grep ($Self->{coverage_filename}, qr/DefaultClock.*,c=>1\);/);
-#file_grep ($Self->{coverage_filename}, qr/ToggleLogIf.*,c=>9\);/);
+#file_grep($Self->{coverage_filename}, qr/t=>'psl_cover',o=>'cover',c=>2\);/);
+#file_grep($Self->{coverage_filename}, qr/DefaultClock.*,c=>1\);/);
+#file_grep($Self->{coverage_filename}, qr/ToggleLogIf.*,c=>9\);/);
 
 ok(1);
 1;
diff --git a/test_regress/t/t_assert_basic_fail.pl b/test_regress/t/t_assert_basic_fail.pl
index 7f32d9b12..1cdff439e 100755
--- a/test_regress/t/t_assert_basic_fail.pl
+++ b/test_regress/t/t_assert_basic_fail.pl
@@ -7,17 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_assert_basic.v");
 
-compile (
-	 v_flags2 => ['+define+FAILING_ASSERTIONS',
-	              $Self->{v3}?'--assert':($Self->{nc}?'+assert':'')],
-	 fails => $Self->{nc},
-	 );
+compile(
+    v_flags2 => ['+define+FAILING_ASSERTIONS',
+                 $Self->{vlt}?'--assert':($Self->{nc}?'+assert':'')],
+    fails => $Self->{nc},
+    );
 
-execute (
-	 fails => $Self->{vlt},
-	 );
+execute(
+    fails => $Self->{vlt},
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_assert_basic_off.pl b/test_regress/t/t_assert_basic_off.pl
index cea1820f6..4945cc73c 100755
--- a/test_regress/t/t_assert_basic_off.pl
+++ b/test_regress/t/t_assert_basic_off.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_assert_basic.v");
 
-compile (
-	 v_flags2 => [],
-	 );
+compile(
+    v_flags2 => [],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_assert_casez.pl b/test_regress/t/t_assert_casez.pl
index b57b2dea8..be109d263 100755
--- a/test_regress/t/t_assert_casez.pl
+++ b/test_regress/t/t_assert_casez.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--assert'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_assert_comp.pl b/test_regress/t/t_assert_comp.pl
index 4eada89db..f97a8c4aa 100755
--- a/test_regress/t/t_assert_comp.pl
+++ b/test_regress/t/t_assert_comp.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--assert'],
     nc_flags2 => ['+assert'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_assert_comp_bad.pl b/test_regress/t/t_assert_comp_bad.pl
index 5733a2bcc..f332531a3 100755
--- a/test_regress/t/t_assert_comp_bad.pl
+++ b/test_regress/t/t_assert_comp_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--assert'],
     nc_flags2 => ['+assert'],
     );
 
-execute (
-    check_finished=>0,
+execute(
+    check_finished => 0,
     fails => 1,
     expect =>
 '.*%Warning: t_assert_comp_bad.v:\d+: Assertion failed in top.t.genblk1: User compile-time warning
diff --git a/test_regress/t/t_assert_cover.pl b/test_regress/t/t_assert_cover.pl
index 04072a897..929ab0cc1 100755
--- a/test_regress/t/t_assert_cover.pl
+++ b/test_regress/t/t_assert_cover.pl
@@ -7,39 +7,41 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_assert_cover.v");
 
-compile (
-	 verilator_flags2 => ['--assert --cc --coverage-user'],
-	 nc_flags2 => ["+nccovoverwrite +nccoverage+all +nccovtest+$Self->{name}"]
-	 );
+compile(
+    verilator_flags2 => ['--assert --cc --coverage-user'],
+    nc_flags2 => ["+nccovoverwrite +nccoverage+all +nccovtest+$Self->{name}"]
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 if ($Self->{nc}) {
     my $name = $Self->{name};
     my $cf = "$Self->{obj_dir}/${name}__nccover.cf";
     {
-	my $fh = IO::File->new(">$cf") or die "%Error: $! writing $cf,";
-	$fh->printf("report_summary -module *\n");
-	$fh->printf("report_detail -both -instance *\n");
-	$fh->printf("report_html -both -instance * > $Self->{obj_dir}/${name}__nccover.html\n");
-	$fh->close;
+        my $fh = IO::File->new(">$cf") or die "%Error: $! writing $cf,";
+        $fh->printf("report_summary -module *\n");
+        $fh->printf("report_detail -both -instance *\n");
+        $fh->printf("report_html -both -instance * > $Self->{obj_dir}/${name}__nccover.html\n");
+        $fh->close;
     }
-    $Self->run(logfile=>"$Self->{obj_dir}/${name}__nccover.log",
-               tee=>0,
-               cmd=>[($ENV{VERILATOR_ICCR}||'iccr'),
-                     "-test ${name} ${cf}"]);
+    run(logfile => "$Self->{obj_dir}/${name}__nccover.log",
+        tee => 0,
+        cmd => [($ENV{VERILATOR_ICCR}||'iccr'),
+                "-test ${name} ${cf}"]);
 }
 
-file_grep ($Self->{run_log_filename}, qr/COVER: Cyc==4/);
-file_grep ($Self->{run_log_filename}, qr/COVER: Cyc==5/);
-file_grep ($Self->{run_log_filename}, qr/COVER: Cyc==6/);
+file_grep($Self->{run_log_filename}, qr/COVER: Cyc==4/);
+file_grep($Self->{run_log_filename}, qr/COVER: Cyc==5/);
+file_grep($Self->{run_log_filename}, qr/COVER: Cyc==6/);
 
 # Allow old Perl format dump, or new binary dump
-file_grep ($Self->{coverage_filename}, qr/(cyc_eq_5.*,c=>[^0]|cyc_eq_5.* [1-9][0-9]*\n)/);
+file_grep($Self->{coverage_filename}, qr/(cyc_eq_5.*,c=>[^0]|cyc_eq_5.* [1-9][0-9]*\n)/);
 
 ok(1);
 1;
diff --git a/test_regress/t/t_assert_cover_off.pl b/test_regress/t/t_assert_cover_off.pl
index 232bf5fc5..5b0c97c27 100755
--- a/test_regress/t/t_assert_cover_off.pl
+++ b/test_regress/t/t_assert_cover_off.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_assert_cover.v");
 
-compile (
-	 v_flags2 => [],
-	 );
+compile(
+    v_flags2 => [],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_assert_dup_bad.pl b/test_regress/t/t_assert_dup_bad.pl
index ffa642fc2..622515a19 100755
--- a/test_regress/t/t_assert_dup_bad.pl
+++ b/test_regress/t/t_assert_dup_bad.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Error: t/t_assert_dup_bad.v:\d+: Duplicate declaration of block: covlabel
 %Error: t/t_assert_dup_bad.v:\d+: ... Location of original declaration
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_assert_elab.pl b/test_regress/t/t_assert_elab.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_assert_elab.pl
+++ b/test_regress/t/t_assert_elab.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_assert_elab_bad.pl b/test_regress/t/t_assert_elab_bad.pl
index 341a150e1..93975dc6c 100755
--- a/test_regress/t/t_assert_elab_bad.pl
+++ b/test_regress/t/t_assert_elab_bad.pl
@@ -7,17 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_assert_elab.v");
 unlink("$Self->{obj_dir}/t_assert_elab_bad.log");
 
 
-compile (
+compile(
     v_flags2 => ['+define+FAILING_ASSERTIONS',
-    $Self->{v3}?'--assert':($Self->{nc}?'+assert':'')],
+    $Self->{vlt}?'--assert':($Self->{nc}?'+assert':'')],
     fails => 1,
 );
 
-execute (
+execute(
     fails => $Self->{vlt},
 );
 
diff --git a/test_regress/t/t_assert_property.pl b/test_regress/t/t_assert_property.pl
index 5dc691360..fd994540c 100755
--- a/test_regress/t/t_assert_property.pl
+++ b/test_regress/t/t_assert_property.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--assert --cc'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_assert_property_fail_1.pl b/test_regress/t/t_assert_property_fail_1.pl
index 69035746b..ae67a4a1b 100755
--- a/test_regress/t/t_assert_property_fail_1.pl
+++ b/test_regress/t/t_assert_property_fail_1.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_assert_property.v");
 
-compile (
+compile(
     v_flags2 => ['+define+FAIL_ASSERT_1'],
     verilator_flags2 => ['--assert --cc'],
     );
 
-execute (
+execute(
     fails => 1
     );
 
diff --git a/test_regress/t/t_assert_property_fail_2.pl b/test_regress/t/t_assert_property_fail_2.pl
index c348e60ab..c5df8f7c3 100755
--- a/test_regress/t/t_assert_property_fail_2.pl
+++ b/test_regress/t/t_assert_property_fail_2.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_assert_property.v");
 
-compile (
+compile(
     v_flags2 => ['+define+FAIL_ASSERT_2'],
     verilator_flags2 => ['--assert --cc'],
     );
 
-execute (
+execute(
     fails => 1
     );
 
diff --git a/test_regress/t/t_assert_question.pl b/test_regress/t/t_assert_question.pl
index b57b2dea8..be109d263 100755
--- a/test_regress/t/t_assert_question.pl
+++ b/test_regress/t/t_assert_question.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--assert'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_assert_synth.pl b/test_regress/t/t_assert_synth.pl
index d4c469bb8..f97a8c4aa 100755
--- a/test_regress/t/t_assert_synth.pl
+++ b/test_regress/t/t_assert_synth.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ['--assert'],
-    	 nc_flags2 => ['+assert'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    verilator_flags2 => ['--assert'],
+    nc_flags2 => ['+assert'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_assert_synth_full.pl b/test_regress/t/t_assert_synth_full.pl
index 30093da53..a9b59a51a 100755
--- a/test_regress/t/t_assert_synth_full.pl
+++ b/test_regress/t/t_assert_synth_full.pl
@@ -7,20 +7,22 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_assert_synth.v");
 
-compile (
-	 v_flags2 => ['+define+FAILING_FULL'],
-	 verilator_flags2 => ['--assert'],
-	 nc_flags2 => ['+assert'],
-	 );
+compile(
+    v_flags2 => ['+define+FAILING_FULL'],
+    verilator_flags2 => ['--assert'],
+    nc_flags2 => ['+assert'],
+    );
 
-execute (
-	 check_finished=>0,
-	 fails=> $Self->{vlt},
-	 expect=>
+execute(
+    check_finished => 0,
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t_assert_synth.v:\d+: Assertion failed in top.t: synthesis full_case'
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_assert_synth_off.pl b/test_regress/t/t_assert_synth_off.pl
index 1b3aee62e..173ff7ad5 100755
--- a/test_regress/t/t_assert_synth_off.pl
+++ b/test_regress/t/t_assert_synth_off.pl
@@ -7,19 +7,21 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_assert_synth.v");
 
-compile (
-	 v_flags2 => ['+define+FAILING_FULL',
-		      '+define+FAILING_PARALLEL',
-		      '+define+FAILING_OH',
-		      '+define+FAILING_OC',
-		      ],
-	 );
+compile(
+    v_flags2 => ['+define+FAILING_FULL',
+                 '+define+FAILING_PARALLEL',
+                 '+define+FAILING_OH',
+                 '+define+FAILING_OC',
+    ],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_assert_synth_parallel.pl b/test_regress/t/t_assert_synth_parallel.pl
index b6776f9c4..5a8a53857 100755
--- a/test_regress/t/t_assert_synth_parallel.pl
+++ b/test_regress/t/t_assert_synth_parallel.pl
@@ -7,20 +7,22 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_assert_synth.v");
 
-compile (
-	 v_flags2 => ['+define+FAILING_PARALLEL'],
-	 verilator_flags2 => ['--assert'],
-	 nc_flags2 => ['+assert'],
-	 );
+compile(
+    v_flags2 => ['+define+FAILING_PARALLEL'],
+    verilator_flags2 => ['--assert'],
+    nc_flags2 => ['+assert'],
+    );
 
-execute (
-	 check_finished=>0,
-	 fails => $Self->{v3},
-	 expect=>
+execute(
+    check_finished => 0,
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t_assert_synth.v:\d+: Assertion failed in top.t: synthesis parallel_case'
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_assign_inline.pl b/test_regress/t/t_assign_inline.pl
index a433bb067..4a4b40f3b 100755
--- a/test_regress/t/t_assign_inline.pl
+++ b/test_regress/t/t_assign_inline.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["-O0 -OG"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_attr_parenstar.pl b/test_regress/t/t_attr_parenstar.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_attr_parenstar.pl
+++ b/test_regress/t/t_attr_parenstar.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_bench_mux4k.pl b/test_regress/t/t_bench_mux4k.pl
index ea52a0ee4..af1ac5c7a 100755
--- a/test_regress/t/t_bench_mux4k.pl
+++ b/test_regress/t/t_bench_mux4k.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--stats"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_bench_synmul.pl b/test_regress/t/t_bench_synmul.pl
index 91f01db79..3073a4cf7 100755
--- a/test_regress/t/t_bench_synmul.pl
+++ b/test_regress/t/t_bench_synmul.pl
@@ -7,6 +7,8 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_math_synmul.v");
 
 $Self->{cycles} = $Self->{benchmark}||0;
@@ -14,12 +16,12 @@ $Self->{cycles} = 100 if $Self->{cycles}<100;
 
 $Self->{sim_time} = $Self->{cycles}*100;
 
-compile (
+compile(
     v_flags2 => ["+define+SIM_CYCLES=$Self->{cycles} --stats"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_bind.pl b/test_regress/t/t_bind.pl
index 30da50378..b1acebe26 100755
--- a/test_regress/t/t_bind.pl
+++ b/test_regress/t/t_bind.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_bind2.pl b/test_regress/t/t_bind2.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_bind2.pl
+++ b/test_regress/t/t_bind2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_bitsel_const_bad.pl b/test_regress/t/t_bitsel_const_bad.pl
index 5e7afe281..a6b950c20 100755
--- a/test_regress/t/t_bitsel_const_bad.pl
+++ b/test_regress/t/t_bitsel_const_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Error: t/t_bitsel_const_bad.v:\d+: Illegal bit or array select; type does not have a bit range, or bad dimension: type is logic
 .*%Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_bitsel_enum.pl b/test_regress/t/t_bitsel_enum.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_bitsel_enum.pl
+++ b/test_regress/t/t_bitsel_enum.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_bitsel_slice.pl b/test_regress/t/t_bitsel_slice.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_bitsel_slice.pl
+++ b/test_regress/t/t_bitsel_slice.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_bitsel_struct.pl b/test_regress/t/t_bitsel_struct.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_bitsel_struct.pl
+++ b/test_regress/t/t_bitsel_struct.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_bitsel_struct2.pl b/test_regress/t/t_bitsel_struct2.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_bitsel_struct2.pl
+++ b/test_regress/t/t_bitsel_struct2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_bitsel_struct3.pl b/test_regress/t/t_bitsel_struct3.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_bitsel_struct3.pl
+++ b/test_regress/t/t_bitsel_struct3.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_bitsel_wire_array_bad.pl b/test_regress/t/t_bitsel_wire_array_bad.pl
index 3a68ce074..7a410958c 100755
--- a/test_regress/t/t_bitsel_wire_array_bad.pl
+++ b/test_regress/t/t_bitsel_wire_array_bad.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # Comple time only test
 
-compile (
+compile(
     verilator_flags2 => ["--lint-only"],
-    fails=>1,
-    expect=>
+    fails => 1,
+    expect =>
 '.*%Error: t/t_bitsel_wire_array_bad.v:\d+: Illegal assignment of constant to unpacked array
 %Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_blocking.pl b/test_regress/t/t_blocking.pl
index 29bf04d49..b1acebe26 100755
--- a/test_regress/t/t_blocking.pl
+++ b/test_regress/t/t_blocking.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_66bits.pl b/test_regress/t/t_case_66bits.pl
index 33c58e257..89a4e77d9 100755
--- a/test_regress/t/t_case_66bits.pl
+++ b/test_regress/t/t_case_66bits.pl
@@ -1,12 +1,20 @@
 #!/usr/bin/perl
 if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_auto1.pl b/test_regress/t/t_case_auto1.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_case_auto1.pl
+++ b/test_regress/t/t_case_auto1.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_deep.pl b/test_regress/t/t_case_deep.pl
index dccd4cf50..803dca735 100755
--- a/test_regress/t/t_case_deep.pl
+++ b/test_regress/t/t_case_deep.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ["--compiler msvc"],  # We have deep expressions we want to test
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ["--compiler msvc"],  # We have deep expressions we want to test
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_default_bad.pl b/test_regress/t/t_case_default_bad.pl
index 5099227eb..da769e338 100755
--- a/test_regress/t/t_case_default_bad.pl
+++ b/test_regress/t/t_case_default_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Error: t/t_case_default_bad.v:\d+: Multiple default statements in case statement.
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_dupitems.pl b/test_regress/t/t_case_dupitems.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_case_dupitems.pl
+++ b/test_regress/t/t_case_dupitems.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_genx_bad.pl b/test_regress/t/t_case_genx_bad.pl
index 85ef7978d..4e0e02d6a 100755
--- a/test_regress/t/t_case_genx_bad.pl
+++ b/test_regress/t/t_case_genx_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Error: t/t_case_genx_bad.v:\d+: Use of x/\? constant in generate case statement, \(no such thing as \'generate casez\'\)
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_group.pl b/test_regress/t/t_case_group.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_case_group.pl
+++ b/test_regress/t/t_case_group.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_case_huge.pl b/test_regress/t/t_case_huge.pl
index 05c89e922..2dfb9cdc0 100755
--- a/test_regress/t/t_case_huge.pl
+++ b/test_regress/t/t_case_huge.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--stats"],
     );
 
@@ -16,8 +18,8 @@ if ($Self->{vlt}) {
     file_grep ($Self->{stats}, qr/Optimizations, Combined CFuncs\s+(\d+)/i, 8);
 }
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_case_huge_prof.pl b/test_regress/t/t_case_huge_prof.pl
index 19d62b5a6..4e34a208b 100755
--- a/test_regress/t/t_case_huge_prof.pl
+++ b/test_regress/t/t_case_huge_prof.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_case_huge.v");
 
-compile (
+compile(
     verilator_flags2 => ["--stats --profile-cfuncs -CFLAGS '-pg' -LDFLAGS '-pg'"],
     );
 
@@ -23,20 +23,20 @@ if ($Self->{vlt}) {
 unlink $_ foreach (glob "$Self->{obj_dir}/gmon.out.*");
 $ENV{GMON_OUT_PREFIX} = "$Self->{obj_dir}/gmon.out";
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 my $gmon_path;
 $gmon_path = $_ foreach (glob "$Self->{obj_dir}/gmon.out.*");
-$gmon_path or $Self->error("Profiler did not create a gmon.out");
+$gmon_path or error("Profiler did not create a gmon.out");
 (my $gmon_base = $gmon_path) =~ s!.*[/\\]!!;
 
-$Self->run(cmd=>["cd $Self->{obj_dir} && gprof $Self->{VM_PREFIX} $gmon_base > gprof.out"],
-           check_finished=>0);
+run(cmd => ["cd $Self->{obj_dir} && gprof $Self->{VM_PREFIX} $gmon_base > gprof.out"],
+    check_finished => 0);
 
-$Self->run(cmd=>["cd $Self->{obj_dir} && $ENV{VERILATOR_ROOT}/bin/verilator_profcfunc gprof.out > cfuncs.out"],
-           check_finished=>0);
+run(cmd => ["cd $Self->{obj_dir} && $ENV{VERILATOR_ROOT}/bin/verilator_profcfunc gprof.out > cfuncs.out"],
+    check_finished => 0);
 
 file_grep ("$Self->{obj_dir}/cfuncs.out", qr/Overall summary by/);
 
diff --git a/test_regress/t/t_case_inside.pl b/test_regress/t/t_case_inside.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_case_inside.pl
+++ b/test_regress/t/t_case_inside.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_case_itemwidth.pl b/test_regress/t/t_case_itemwidth.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_case_itemwidth.pl
+++ b/test_regress/t/t_case_itemwidth.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_nest.pl b/test_regress/t/t_case_nest.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_case_nest.pl
+++ b/test_regress/t/t_case_nest.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_onehot.pl b/test_regress/t/t_case_onehot.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_case_onehot.pl
+++ b/test_regress/t/t_case_onehot.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_orig.pl b/test_regress/t/t_case_orig.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_case_orig.pl
+++ b/test_regress/t/t_case_orig.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_reducer.pl b/test_regress/t/t_case_reducer.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_case_reducer.pl
+++ b/test_regress/t/t_case_reducer.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_case_wild.pl b/test_regress/t/t_case_wild.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_case_wild.pl
+++ b/test_regress/t/t_case_wild.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_write1.pl b/test_regress/t/t_case_write1.pl
index b0a0163c6..50b2ba9d1 100755
--- a/test_regress/t/t_case_write1.pl
+++ b/test_regress/t/t_case_write1.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 $Self->{golden_out} ||= "t/$Self->{name}.out";
 
-compile (
-	 verilator_flags2 => ["--stats --O3 -x-assign fast"],
-	 );
+compile(
+    verilator_flags2 => ["--stats --O3 -x-assign fast"],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(files_identical("$Self->{obj_dir}/$Self->{name}_logger.log", $Self->{golden_out}));
 1;
diff --git a/test_regress/t/t_case_write1.v b/test_regress/t/t_case_write1.v
index aa2d1d09b..a5856066c 100644
--- a/test_regress/t/t_case_write1.v
+++ b/test_regress/t/t_case_write1.v
@@ -5,6 +5,8 @@
 
 `include "verilated.v"
 
+`define STRINGIFY(x) `"x`"
+
 module t (/*AUTOARG*/
    // Inputs
    clk
@@ -14,6 +16,7 @@ module t (/*AUTOARG*/
 
    reg [63:0] crc;
    `verilator_file_descriptor	  fd;
+   `verilator_file_descriptor	  fdtmp;
 
    t_case_write1_tasks tasks ();
 
@@ -31,8 +34,9 @@ module t (/*AUTOARG*/
       crc <= {crc[62:0], crc[63]^crc[2]^crc[0]};
       if (cyc==1) begin
 	 crc <= 64'h00000000_00000097;
-	 $write("Open obj_dir/t_case_write1/t_case_write1_logger.log\n");
-	 fd = $fopen("obj_dir/t_case_write1/t_case_write1_logger.log", "w");
+         $write("%s", {"Open ", `STRINGIFY(`TEST_OBJ_DIR), "/t_case_write1_logger.log\n"});
+         fdtmp = $fopen({`STRINGIFY(`TEST_OBJ_DIR), "/t_case_write1_logger.log"}, "w");
+         fd <= fdtmp;
       end
       if (cyc==90) begin
 	 $write("*-* All Finished *-*\n");
diff --git a/test_regress/t/t_case_write2.pl b/test_regress/t/t_case_write2.pl
index 0d5c0beb2..104eba11b 100755
--- a/test_regress/t/t_case_write2.pl
+++ b/test_regress/t/t_case_write2.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 $Self->{golden_out} ||= "t/$Self->{name}.out";
 
-compile (
-	 verilator_flags2 => ["--stats --O3 -x-assign fast"],
-	 );
+compile(
+    verilator_flags2 => ["--stats --O3 -x-assign fast"],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(files_identical("$Self->{obj_dir}/$Self->{name}_logger.log", $Self->{golden_out}));
 
diff --git a/test_regress/t/t_case_write2.v b/test_regress/t/t_case_write2.v
index 9f69750f2..07215dd6d 100644
--- a/test_regress/t/t_case_write2.v
+++ b/test_regress/t/t_case_write2.v
@@ -5,6 +5,8 @@
 
 `include "verilated.v"
 
+`define STRINGIFY(x) `"x`"
+
 module t (/*AUTOARG*/
    // Inputs
    clk
@@ -14,6 +16,7 @@ module t (/*AUTOARG*/
 
    reg [63:0] crc;
    `verilator_file_descriptor	  fd;
+   `verilator_file_descriptor	  fdtmp;
 
    t_case_write2_tasks tasks ();
 
@@ -31,8 +34,9 @@ module t (/*AUTOARG*/
       crc <= {crc[62:0], crc[63]^crc[2]^crc[0]};
       if (cyc==1) begin
 	 crc <= 64'h00000000_00000097;
-	 $write("Open obj_dir/t_case_write2/t_case_write2_logger.log\n");
-	 fd = $fopen("obj_dir/t_case_write2/t_case_write2_logger.log", "w");
+         $write("%s", {"Open ", `STRINGIFY(`TEST_OBJ_DIR), "/t_case_write2_logger.log\n"});
+         fdtmp = $fopen({`STRINGIFY(`TEST_OBJ_DIR), "/t_case_write2_logger.log"}, "w");
+         fd <= fdtmp;
       end
       if (cyc==90) begin
 	 $write("*-* All Finished *-*\n");
diff --git a/test_regress/t/t_case_x.pl b/test_regress/t/t_case_x.pl
index bbefb98ca..53262ac3e 100755
--- a/test_regress/t/t_case_x.pl
+++ b/test_regress/t/t_case_x.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ["--x-assign 0"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ["--x-assign 0"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_x_bad.pl b/test_regress/t/t_case_x_bad.pl
index 2bdad4fba..770624d54 100755
--- a/test_regress/t/t_case_x_bad.pl
+++ b/test_regress/t/t_case_x_bad.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Warning-CASEX: t/t_case_x_bad.v:\d+: Suggest casez \(with \?\'s\) in place of casex \(with X\'s\)
 .*%Warning-CASEWITHX: t/t_case_x_bad.v:\d+: Use of x/\? constant in case statement, \(perhaps intended casex/casez\)
 .*%Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_case_zx_bad.pl b/test_regress/t/t_case_zx_bad.pl
index 962fd0a9a..f7d269d18 100755
--- a/test_regress/t/t_case_zx_bad.pl
+++ b/test_regress/t/t_case_zx_bad.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Warning-CASEWITHX: t/t_case_zx_bad.v:\d+: Use of x constant in casez statement, \(perhaps intended \?/z in constant\)
 .*
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_cast.pl b/test_regress/t/t_cast.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_cast.pl
+++ b/test_regress/t/t_cast.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_cdc_async_bad.pl b/test_regress/t/t_cdc_async_bad.pl
index d231e9506..4c7f7e1f0 100755
--- a/test_regress/t/t_cdc_async_bad.pl
+++ b/test_regress/t/t_cdc_async_bad.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags => ['--cdc'],
-	 verilator_make_gcc => 0,
-	 fails => 1,
-	 expect=>
+scenarios(vlt => 1);
+
+compile(
+    v_flags => ['--cdc'],
+    verilator_make_gcc => 0,
+    fails => 1,
+    expect =>
 '%Warning-CDCRSTLOGIC: t/t_cdc_async_bad.v:\d+: Logic in path that feeds async reset, via signal: t.rst2_bad_n
 %Warning-CDCRSTLOGIC: Use "/\* verilator lint_off CDCRSTLOGIC \*/" and lint_on around source to disable this message.
-%Warning-CDCRSTLOGIC:      See details in obj_dir/t_cdc_async_bad/Vt_cdc_async_bad__cdc.txt
+%Warning-CDCRSTLOGIC:      See details in obj_vlt/t_cdc_async_bad/Vt_cdc_async_bad__cdc.txt
 %Warning-CDCRSTLOGIC: t/t_cdc_async_bad.v:\d+: Logic in path that feeds async reset, via signal: t.rst6a_bad_n
 %Warning-CDCRSTLOGIC: t/t_cdc_async_bad.v:\d+: Logic in path that feeds async reset, via signal: t.rst6b_bad_n
 %Error: Exiting due to.*',
-	 );
+    );
 
 file_grep ("$Self->{obj_dir}/V$Self->{name}__cdc.txt", qr/CDC Report/);
 
diff --git a/test_regress/t/t_cellarray.pl b/test_regress/t/t_cellarray.pl
index b39a34d2a..804a7e23f 100755
--- a/test_regress/t/t_cellarray.pl
+++ b/test_regress/t/t_cellarray.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    v_flags2 => ["--stats"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    v_flags2 => ["--stats"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 if ($Self->{vlt}) {
     file_grep ($Self->{stats}, qr/Optimizations, Gate assign merged\s+(\d+)/i, 28);
diff --git a/test_regress/t/t_chg_first.pl b/test_regress/t/t_chg_first.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_chg_first.pl
+++ b/test_regress/t/t_chg_first.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_clk_2in.pl b/test_regress/t/t_clk_2in.pl
index c06cdc013..9189ff808 100755
--- a/test_regress/t/t_clk_2in.pl
+++ b/test_regress/t/t_clk_2in.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     make_top_shell => 0,
     make_main => 0,
     verilator_flags2 => ["--exe","$Self->{t_dir}/$Self->{name}.cpp"],
     vcs_flags2 => ['-assert'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_clk_2in_vec.pl b/test_regress/t/t_clk_2in_vec.pl
index 7fac6f163..e39511b25 100755
--- a/test_regress/t/t_clk_2in_vec.pl
+++ b/test_regress/t/t_clk_2in_vec.pl
@@ -7,17 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_clk_2in.v");
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 v_flags2 => ["+define+T_CLK_2IN_VEC=1"],
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_clk_2in.cpp"],
-	 );
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    v_flags2 => ["+define+T_CLK_2IN_VEC=1"],
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_clk_2in.cpp"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
-execute (
-	 check_finished=>1,
-	 );
 ok(1);
 1;
diff --git a/test_regress/t/t_clk_concat.pl b/test_regress/t/t_clk_concat.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_clk_concat.pl
+++ b/test_regress/t/t_clk_concat.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_clk_concat2.pl b/test_regress/t/t_clk_concat2.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_clk_concat2.pl
+++ b/test_regress/t/t_clk_concat2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_clk_concat3.pl b/test_regress/t/t_clk_concat3.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_clk_concat3.pl
+++ b/test_regress/t/t_clk_concat3.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_clk_concat4.pl b/test_regress/t/t_clk_concat4.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_clk_concat4.pl
+++ b/test_regress/t/t_clk_concat4.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_clk_concat5.pl b/test_regress/t/t_clk_concat5.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_clk_concat5.pl
+++ b/test_regress/t/t_clk_concat5.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_clk_concat6.pl b/test_regress/t/t_clk_concat6.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_clk_concat6.pl
+++ b/test_regress/t/t_clk_concat6.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_clk_condflop.pl b/test_regress/t/t_clk_condflop.pl
index 302562ae9..48b77b922 100755
--- a/test_regress/t/t_clk_condflop.pl
+++ b/test_regress/t/t_clk_condflop.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished => 1
-	 );
+compile(
+    );
+
+execute(
+    check_finished => 1
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_clk_condflop_nord.pl b/test_regress/t/t_clk_condflop_nord.pl
index 15f9af180..7835b7a30 100755
--- a/test_regress/t/t_clk_condflop_nord.pl
+++ b/test_regress/t/t_clk_condflop_nord.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2=>["-no-order-clock-delay"],
     );
 
-execute (
+execute(
     check_finished => 1
     );
 
diff --git a/test_regress/t/t_clk_dpulse.pl b/test_regress/t/t_clk_dpulse.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_clk_dpulse.pl
+++ b/test_regress/t/t_clk_dpulse.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_clk_dsp.pl b/test_regress/t/t_clk_dsp.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_clk_dsp.pl
+++ b/test_regress/t/t_clk_dsp.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_clk_first.pl b/test_regress/t/t_clk_first.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_clk_first.pl
+++ b/test_regress/t/t_clk_first.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_clk_gater.pl b/test_regress/t/t_clk_gater.pl
index b8116f631..0acb40826 100755
--- a/test_regress/t/t_clk_gater.pl
+++ b/test_regress/t/t_clk_gater.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--stats"],
     );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 if ($Self->{vlt}) {
     #Optimization is disabled
diff --git a/test_regress/t/t_clk_gen.pl b/test_regress/t/t_clk_gen.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_clk_gen.pl
+++ b/test_regress/t/t_clk_gen.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_clk_latch.pl b/test_regress/t/t_clk_latch.pl
index f6d3de4c4..11b8aeb6b 100755
--- a/test_regress/t/t_clk_latch.pl
+++ b/test_regress/t/t_clk_latch.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-my $fail = ($Self->{v3} && verilator_version() !~ /\(ord\)/);
+scenarios(simulator => 1);
 
-compile (
-	 );
+my $fail = ($Self->{vlt} && verilator_version() !~ /\(ord\)/);
 
-execute (
-	 check_finished => !$fail,
-	 fails => $fail,
-	 );
+compile(
+    );
+
+execute(
+    check_finished => !$fail,
+    fails => $fail,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_clk_latch_edgestyle.pl b/test_regress/t/t_clk_latch_edgestyle.pl
index 9975c5bdc..59fa5393b 100755
--- a/test_regress/t/t_clk_latch_edgestyle.pl
+++ b/test_regress/t/t_clk_latch_edgestyle.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_clk_latch.v");
 
-my $fail = ($Self->{v3} && verilator_version() !~ /\(ord\)/);
+my $fail = ($Self->{vlt} && verilator_version() !~ /\(ord\)/);
 
-compile (
-	 v_flags2 => ['+define+EDGE_DETECT_STYLE'],
-	 fails => $fail,
-	 );
+compile(
+    v_flags2 => ['+define+EDGE_DETECT_STYLE'],
+    fails => $fail,
+    );
 
-execute (
-	 check_finished => !$fail,
-	 ) if !$fail;
+execute(
+    check_finished => !$fail,
+    ) if !$fail;
 
 ok(1);
 1;
diff --git a/test_regress/t/t_clk_latchgate.pl b/test_regress/t/t_clk_latchgate.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_clk_latchgate.pl
+++ b/test_regress/t/t_clk_latchgate.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_clk_powerdn.pl b/test_regress/t/t_clk_powerdn.pl
index 302562ae9..48b77b922 100755
--- a/test_regress/t/t_clk_powerdn.pl
+++ b/test_regress/t/t_clk_powerdn.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished => 1
-	 );
+compile(
+    );
+
+execute(
+    check_finished => 1
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_clk_vecgen1.pl b/test_regress/t/t_clk_vecgen1.pl
index 1dd4c0942..2605f221a 100755
--- a/test_regress/t/t_clk_vecgen1.pl
+++ b/test_regress/t/t_clk_vecgen1.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_clk_vecgen1.v");
 
-compile (
+compile(
     v_flags2 => ['+define+T_TEST1',],
     );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_clk_vecgen2.pl b/test_regress/t/t_clk_vecgen2.pl
index 7d8054dd9..fce42e49d 100755
--- a/test_regress/t/t_clk_vecgen2.pl
+++ b/test_regress/t/t_clk_vecgen2.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_clk_vecgen1.v");
 
-compile (
+compile(
     v_flags2 => ['+define+T_TEST2',],
     );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_clk_vecgen3.pl b/test_regress/t/t_clk_vecgen3.pl
index 677057029..4cb74b187 100755
--- a/test_regress/t/t_clk_vecgen3.pl
+++ b/test_regress/t/t_clk_vecgen3.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_clk_vecgen1.v");
 
-compile (
+compile(
     v_flags2 => ['+define+T_TEST3',],
     );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_clocker.pl b/test_regress/t/t_clocker.pl
index 7a1792c6f..8997efa90 100755
--- a/test_regress/t/t_clocker.pl
+++ b/test_regress/t/t_clocker.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
 #    verilator_flags2 => ["-Wno-UNOPTFLAT"]
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_concat_large.pl b/test_regress/t/t_concat_large.pl
index 30da50378..b1acebe26 100755
--- a/test_regress/t/t_concat_large.pl
+++ b/test_regress/t/t_concat_large.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_concat_large_bad.pl b/test_regress/t/t_concat_large_bad.pl
index 5a848e0a2..410c391bf 100755
--- a/test_regress/t/t_concat_large_bad.pl
+++ b/test_regress/t/t_concat_large_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>1,
-    expect=>
+    fails => 1,
+    expect =>
 '%Warning-WIDTHCONCAT: t/t_concat_large_bad.v:\d+: More than a 8k bit replication is probably wrong: 32768
 %Warning-WIDTHCONCAT: Use .*
 %Error: Exiting due to.*',
diff --git a/test_regress/t/t_concat_opt.pl b/test_regress/t/t_concat_opt.pl
index 29bf04d49..b1acebe26 100755
--- a/test_regress/t/t_concat_opt.pl
+++ b/test_regress/t/t_concat_opt.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_const_dec_mixed_bad.pl b/test_regress/t/t_const_dec_mixed_bad.pl
index f7d0ec546..822214e6c 100755
--- a/test_regress/t/t_const_dec_mixed_bad.pl
+++ b/test_regress/t/t_const_dec_mixed_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Error: t/t_const_dec_mixed_bad.v:\d+: Mixing X/Z/\? with digits not legal in decimal constant: x_1
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_const_overflow_bad.pl b/test_regress/t/t_const_overflow_bad.pl
index c40d4c6cb..2fc1f09dd 100755
--- a/test_regress/t/t_const_overflow_bad.pl
+++ b/test_regress/t/t_const_overflow_bad.pl
@@ -7,16 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Error: t/t_const_overflow_bad.v:\d+: Too many digits for 94 bit number: 94\'d123456789012345678901234567890
 %Error: t/t_const_overflow_bad.v:\d+: Too many digits for 8 bit number: 8\'habc
 %Error: t/t_const_overflow_bad.v:\d+: Too many digits for 6 bit number: 6\'o1234
 %Error: t/t_const_overflow_bad.v:\d+: Too many digits for 3 bit number: 3\'b1111
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_cover_line_cc.pl b/test_regress/t/t_cover_line_cc.pl
index 7e2999874..1a4e7318a 100755
--- a/test_regress/t/t_cover_line_cc.pl
+++ b/test_regress/t/t_cover_line_cc.pl
@@ -7,24 +7,25 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_cover_line.v");
 
-compile (
+compile(
     verilator_flags2 => ['--cc --coverage-line'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 # Read the input .v file and do any CHECK_COVER requests
 inline_checks();
 
-$Self->run(cmd=>["../bin/verilator_coverage",
-                 "--annotate", "$Self->{obj_dir}/annotated",
-                 "$Self->{obj_dir}/coverage.dat",
-           ],
-    );
+run(cmd => ["../bin/verilator_coverage",
+            "--annotate", "$Self->{obj_dir}/annotated",
+            "$Self->{obj_dir}/coverage.dat",
+    ]);
 
 ok(files_identical("$Self->{obj_dir}/annotated/t_cover_line.v", "t/t_cover_line.out"));
 
diff --git a/test_regress/t/t_cover_line_sc.pl b/test_regress/t/t_cover_line_sc.pl
index 2d5faf39d..cde76f21f 100755
--- a/test_regress/t/t_cover_line_sc.pl
+++ b/test_regress/t/t_cover_line_sc.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_cover_line.v");
 
-compile (
-	 verilator_flags2 => ['--sc --coverage-line'],
-	 );
+compile(
+    verilator_flags2 => ['--sc --coverage-line'],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 # Read the input .v file and do any CHECK_COVER requests
 inline_checks();
diff --git a/test_regress/t/t_cover_sva_notflat.pl b/test_regress/t/t_cover_sva_notflat.pl
index 5b60c8781..b5f179331 100755
--- a/test_regress/t/t_cover_sva_notflat.pl
+++ b/test_regress/t/t_cover_sva_notflat.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ['--assert --cc --coverage-user'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    verilator_flags2 => ['--assert --cc --coverage-user'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 #if ($Self->{nc}) ... # See t_assert_cover.pl for NC version
 
diff --git a/test_regress/t/t_cover_toggle.pl b/test_regress/t/t_cover_toggle.pl
index 274713088..39b21de2a 100755
--- a/test_regress/t/t_cover_toggle.pl
+++ b/test_regress/t/t_cover_toggle.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ['--cc --coverage-toggle --stats'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    verilator_flags2 => ['--cc --coverage-toggle --stats'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 # Read the input .v file and do any CHECK_COVER requests
 inline_checks();
diff --git a/test_regress/t/t_crazy_sel.pl b/test_regress/t/t_crazy_sel.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_crazy_sel.pl
+++ b/test_regress/t/t_crazy_sel.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_debug_fatalsrc_bad.pl b/test_regress/t/t_debug_fatalsrc_bad.pl
index e8f5acd76..85490cb46 100755
--- a/test_regress/t/t_debug_fatalsrc_bad.pl
+++ b/test_regress/t/t_debug_fatalsrc_bad.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
-	 verilator_flags2 => ["--debug-fatalsrc"],
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    verilator_flags2 => ["--debug-fatalsrc"],
+    fails => $Self->{vlt},
+    expect =>
 '%Error: Internal Error: .*: --debug-fatal-src
 %Error: Internal Error: See the manual and http://www.veripool.org/verilator for more assistance.
 %Error: Command Failed.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_debug_fatalsrc_bt_bad.pl b/test_regress/t/t_debug_fatalsrc_bt_bad.pl
index 29dc773e2..9179fb9e1 100755
--- a/test_regress/t/t_debug_fatalsrc_bt_bad.pl
+++ b/test_regress/t/t_debug_fatalsrc_bt_bad.pl
@@ -7,17 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$ENV{VERILATOR_TEST_NO_GDB} and $Self->skip("Skipping due to VERILATOR_TEST_NO_GDB");
+scenarios(vlt => 1);
+$ENV{VERILATOR_TEST_NO_GDB} and skip("Skipping due to VERILATOR_TEST_NO_GDB");
 
-compile (
-	 v_flags2 => ["--lint-only --debug --gdbbt --debug-fatalsrc"],
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only --debug --gdbbt --debug-fatalsrc"],
+    fails => $Self->{vlt},
+    expect =>
 '%Error: Internal Error: .*: --debug-fatal-src
 %Error: Internal Error: See the manual and http://www.veripool.org/verilator for more assistance.
 .*in V3Options::.*
 .*%Error: Command Failed.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_debug_sigsegv_bad.pl b/test_regress/t/t_debug_sigsegv_bad.pl
index 2589a21f8..0a634bb0b 100755
--- a/test_regress/t/t_debug_sigsegv_bad.pl
+++ b/test_regress/t/t_debug_sigsegv_bad.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-$ENV{VERILATOR_TEST_NO_GDB} and $Self->skip("Skipping due to VERILATOR_TEST_NO_GDB");
+scenarios(vlt => 1);
+$ENV{VERILATOR_TEST_NO_GDB} and skip("Skipping due to VERILATOR_TEST_NO_GDB");
 
-compile (
-	 verilator_flags2 => ["--debug-sigsegv"],
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    v_flags => ["--debug-sigsegv"],
+    fails => $Self->{vlt},
+    expect =>
 '%Error: Verilator internal fault, sorry.  Consider trying --debug --gdbbt
 %Error: Command Failed.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_debug_sigsegv_bt_bad.pl b/test_regress/t/t_debug_sigsegv_bt_bad.pl
index 39ae42ab9..a6085df84 100755
--- a/test_regress/t/t_debug_sigsegv_bt_bad.pl
+++ b/test_regress/t/t_debug_sigsegv_bt_bad.pl
@@ -7,17 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$ENV{VERILATOR_TEST_NO_GDB} and $Self->skip("Skipping due to VERILATOR_TEST_NO_GDB");
+scenarios(vlt => 1);
+$ENV{VERILATOR_TEST_NO_GDB} and skip("Skipping due to VERILATOR_TEST_NO_GDB");
 
-compile (
-	 v_flags2 => ["--lint-only --debug --gdbbt --debug-sigsegv"],
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only --debug --gdbbt --debug-sigsegv"],
+    fails => $Self->{vlt},
+    expect =>
 '.*
 Program received signal SIGSEGV, Segmentation fault.
 .*in V3Options::.*
 .*%Error: Command Failed.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dedupe_clk_gate.pl b/test_regress/t/t_dedupe_clk_gate.pl
index 6cd30aa41..b392f2b3b 100755
--- a/test_regress/t/t_dedupe_clk_gate.pl
+++ b/test_regress/t/t_dedupe_clk_gate.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--stats"],
     );
 
diff --git a/test_regress/t/t_dedupe_seq_logic.pl b/test_regress/t/t_dedupe_seq_logic.pl
index eb80a4317..a01f1a898 100755
--- a/test_regress/t/t_dedupe_seq_logic.pl
+++ b/test_regress/t/t_dedupe_seq_logic.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--stats"],
     );
 
diff --git a/test_regress/t/t_delay.pl b/test_regress/t/t_delay.pl
index 41773e35e..c56a826e8 100755
--- a/test_regress/t/t_delay.pl
+++ b/test_regress/t/t_delay.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ['-Wno-STMTDLY -Wno-ASSIGNDLY'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ['-Wno-STMTDLY -Wno-ASSIGNDLY'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_delay_stmtdly_bad.pl b/test_regress/t/t_delay_stmtdly_bad.pl
index 9e5bd4717..3bd5845cc 100755
--- a/test_regress/t/t_delay_stmtdly_bad.pl
+++ b/test_regress/t/t_delay_stmtdly_bad.pl
@@ -7,21 +7,21 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_delay.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 verilator_flags2 => ['-Wall -Wno-DECLFILENAME'],
-	 fails=>1,
-	 expect=>
+compile(
+    verilator_flags2 => ['-Wall -Wno-DECLFILENAME'],
+    fails => 1,
+    expect =>
 '%Warning-ASSIGNDLY: t/t_delay.v:\d+: Unsupported: Ignoring delay on this assignment/primitive.
 %Warning-ASSIGNDLY: Use .*
 %Warning-ASSIGNDLY: t/t_delay.v:\d+: Unsupported: Ignoring delay on this assignment/primitive.
 %Warning-ASSIGNDLY: t/t_delay.v:\d+: Unsupported: Ignoring delay on this assignment/primitive.
 %Warning-STMTDLY: t/t_delay.v:\d+: Unsupported: Ignoring delay on this delayed statement.
 .*%Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_detectarray_1.pl b/test_regress/t/t_detectarray_1.pl
index 86c7dd2ec..0a3b50107 100755
--- a/test_regress/t/t_detectarray_1.pl
+++ b/test_regress/t/t_detectarray_1.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["-Wno-CLKDATA"]
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_detectarray_2.pl b/test_regress/t/t_detectarray_2.pl
index 86c7dd2ec..0a3b50107 100755
--- a/test_regress/t/t_detectarray_2.pl
+++ b/test_regress/t/t_detectarray_2.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["-Wno-CLKDATA"]
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_detectarray_3.pl b/test_regress/t/t_detectarray_3.pl
index 0ab9fe201..4fd888569 100755
--- a/test_regress/t/t_detectarray_3.pl
+++ b/test_regress/t/t_detectarray_3.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["-Wno-UNOPTFLAT -Wno-WIDTH"]
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_display.pl b/test_regress/t/t_display.pl
index 149430a83..f2d31d473 100755
--- a/test_regress/t/t_display.pl
+++ b/test_regress/t/t_display.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
-    expect=>dequote(
+execute(
+    check_finished => 1,
+    expect => dequote(
 q{[0] In top.t: Hi
 [0] In top.t.sub (sub)
 [0] In top.t.sub.subblock (sub)
diff --git a/test_regress/t/t_display_bad.pl b/test_regress/t/t_display_bad.pl
index a43289ea7..796da5092 100755
--- a/test_regress/t/t_display_bad.pl
+++ b/test_regress/t/t_display_bad.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Error: t/t_display_bad.v:\d+: Missing arguments for \$display-like format
 %Error: t/t_display_bad.v:\d+: Unknown \$display-like format code: %q
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_display_l.pl b/test_regress/t/t_display_l.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_display_l.pl
+++ b/test_regress/t/t_display_l.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_display_mcd.pl b/test_regress/t/t_display_mcd.pl
index 13b318c77..26266f883 100755
--- a/test_regress/t/t_display_mcd.pl
+++ b/test_regress/t/t_display_mcd.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 expect=>quotemeta(dequote(
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    expect => quotemeta(dequote(
 'To stdout
 To stderr
 *-* All Finished *-*
diff --git a/test_regress/t/t_display_merge.pl b/test_regress/t/t_display_merge.pl
index 6918a7df9..9e3d22c1f 100755
--- a/test_regress/t/t_display_merge.pl
+++ b/test_regress/t/t_display_merge.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2=>["--stats"],
     );
 
-execute (
-    check_finished=>1,
-    expect=> (quotemeta(
+execute(
+    check_finished => 1,
+    expect => (quotemeta(
 'Merge:
 This should merge
 f
@@ -33,11 +35,11 @@ mm
 f a=top.t b=top.t pre t=0 t2=0 post t3=0 t4=0 t5=00000000000000000m t=0 t2=0 t3=0 t4=0 t5=0 t=0 t2=0 t3=0 t4=0 t5=0mm
 
 *-* All Finished *-*')
-	      .'.*')
+              .'.*')
     );
 
 file_grep ("$Self->{obj_dir}/$Self->{VM_PREFIX}__stats.txt",
-	   qr/Node count, DISPLAY \s+ 32 \s+ 25 \s+ 25 \s+ 25/);
+           qr/Node count, DISPLAY \s+ 32 \s+ 25 \s+ 25 \s+ 25/);
 
 ok(1);
 1;
diff --git a/test_regress/t/t_display_noopt.pl b/test_regress/t/t_display_noopt.pl
index 3649d5f22..ee29d6649 100755
--- a/test_regress/t/t_display_noopt.pl
+++ b/test_regress/t/t_display_noopt.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_display.v");
 
-compile (
+compile(
     verilator_flags2 => ["-O0"],
     );
 
-execute (
-    check_finished=>1,
-    expect=>dequote(
+execute(
+    check_finished => 1,
+    expect => dequote(
 q{[0] In top.t: Hi
 [0] In top.t.sub (sub)
 [0] In top.t.sub.subblock (sub)
diff --git a/test_regress/t/t_display_real.pl b/test_regress/t/t_display_real.pl
index f59c69037..98aee4fa0 100755
--- a/test_regress/t/t_display_real.pl
+++ b/test_regress/t/t_display_real.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 expect=> quotemeta(
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    expect => quotemeta(
 '[0] e=0.000000e+00 e1=0.000000e+00 e30=0e+00 e32=0.00e+00
 [0] f=0.000000 f1=0.000000e+00 f30=0e+00 f32=0.00e+00
 [0] g=0 g1=0.000000e+00 g30=0e+00 g32=0.00e+00
diff --git a/test_regress/t/t_display_real_noopt.pl b/test_regress/t/t_display_real_noopt.pl
index 05c7f7061..2b8ccddf9 100755
--- a/test_regress/t/t_display_real_noopt.pl
+++ b/test_regress/t/t_display_real_noopt.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_display_real.v");
 
-compile (
-	 verilator_flags2 => ["-O0"],
-	 );
+compile(
+    verilator_flags2 => ["-O0"],
+    );
 
-execute (
-	 check_finished=>1,
-	 expect=> quotemeta(
+execute(
+    check_finished => 1,
+    expect => quotemeta(
 '[0] e=0.000000e+00 e1=0.000000e+00 e30=0e+00 e32=0.00e+00
 [0] f=0.000000 f1=0.000000e+00 f30=0e+00 f32=0.00e+00
 [0] g=0 g1=0.000000e+00 g30=0e+00 g32=0.00e+00
diff --git a/test_regress/t/t_display_signed.pl b/test_regress/t/t_display_signed.pl
index f28067afa..7fbb489b5 100755
--- a/test_regress/t/t_display_signed.pl
+++ b/test_regress/t/t_display_signed.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 expect=> quotemeta(
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    expect => quotemeta(
 '[0] lp %x=0bbccc %x=0bbccc %o=2736314 %b=010111011110011001100 %0d=769228 %d=  769228
 [0] ln %x=1bbccc %x=1bbccc %o=6736314 %b=110111011110011001100 %0d=-279348 %d= -279348
 [0] qp %x=001bbbbcccc %x=001bbbbcccc %o=00067356746314 %b=00000000110111011101110111100110011001100 %0d=7444614348 %d=    7444614348
diff --git a/test_regress/t/t_display_signed_noopt.pl b/test_regress/t/t_display_signed_noopt.pl
index c8a06bb6b..104839544 100755
--- a/test_regress/t/t_display_signed_noopt.pl
+++ b/test_regress/t/t_display_signed_noopt.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_display_signed.v");
 
-compile (
-	 verilator_flags2 => ["-O0"],
-	 );
+compile(
+    verilator_flags2 => ["-O0"],
+    );
 
-execute (
-	 check_finished=>1,
-	 expect=> quotemeta(
+execute(
+    check_finished => 1,
+    expect => quotemeta(
 '[0] lp %x=0bbccc %x=0bbccc %o=2736314 %b=010111011110011001100 %0d=769228 %d=  769228
 [0] ln %x=1bbccc %x=1bbccc %o=6736314 %b=110111011110011001100 %0d=-279348 %d= -279348
 [0] qp %x=001bbbbcccc %x=001bbbbcccc %o=00067356746314 %b=00000000110111011101110111100110011001100 %0d=7444614348 %d=    7444614348
diff --git a/test_regress/t/t_display_time.pl b/test_regress/t/t_display_time.pl
index ff206c6d8..6bdd258fc 100755
--- a/test_regress/t/t_display_time.pl
+++ b/test_regress/t/t_display_time.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 $Self->{vl_time_multiplier} = 1000;
 
-compile (
+compile(
     verilator_flags2 => ['-DVL_TIME_MULTIPLER=1000'],
     );
 
-execute (
-	 check_finished=>1,
-	 expect=> quotemeta(
+execute(
+    check_finished => 1,
+    expect => quotemeta(
 'default:   [0.000] 0t time [               0.000] No0 time
 '
 # Unsupported:
diff --git a/test_regress/t/t_display_wide.pl b/test_regress/t/t_display_wide.pl
index 20302e6b4..d27f62e4e 100755
--- a/test_regress/t/t_display_wide.pl
+++ b/test_regress/t/t_display_wide.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 $Self->{vl_time_multiplier} = 1000;
 
-compile (
+compile(
     );
 
-execute (
-	 check_finished=>1,
-	 expect=> quotemeta(
+execute(
+    check_finished => 1,
+    expect => quotemeta(
 '[1000.000] cyc==99 crc=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
 [1000.000] cyc==99 crc=001010010110000110010010011011101101110111100011111001011100011000000001100010111110100101110000110011011011111100110010011110110111001010110101111100111100010111101010101101000010100110010101100010010001000000000101111011101100100001110110011111100101111111011111000000110000010100011110110110111110100111010010001000101110111001110101011011101110001101001101100011010110110010000011111011101000011101111010101011010110010111000100100001110001010000001010110010000111110100100110110001100011011010100110011000100001010010110100101001101001101011001010110110010010010011000101011010001100110010001110100011000111100111111001011111010000011110100110111011101101111110010001000000010001100100011001110100001110001111001101110110100101001000010101111011100101100011001001010000101111011011000100110111101010010010001011001111110011100010101011110001110111101111110100011111100100111101101101011010101000010110011111110011000101101101011101010001101110110010011101001011110110101001011011111101111011100101111000101100011011101001111100101000010101110100000111000100111010001011101011000001101010110111100001010101110000110001001110001110100001001011011011011010000111011000100101111011101111100011011111111010111100101101000000100101011010101101001011110111111111111001111001110000010010100110001111011000001001001100000111101001011110111101110111001110100110010000110010101110000101010111100011111001010100110111101011100010001100101000110100001010111111010110100111111111101100110001011111001011110011111000010110010110100101100111001101101110010001011110010111000110001010001011010001000111001001110101010101111100010100110101101001111101000000101100000001111001000001111111001011011100110011010110101000100001110010101001101011101001111000011101101110110001101000010011010110101000111010111100001011100000101010101000110001110011001010011011100010011000110100000010100010010110001001110011110111101111111000100001101111101010101000110100100011100001000100010110010110110111000111000100100011001111000111000000100101110001010010010100001010100101101000101101110111000010101011011100101101101110010000101100000011110110001100000001000101111110111000100001001000000101011001110111110101010001001010001110100011101111110000011000110010011010011011111000001010101000010001110101010101000001111111010111001000101100110010100010110111011000001010011011011111100111100011111110111110001001110110111110101010110110001110101011011110111000010010011001000100001110101101001111111001100111010101100101011011000100101101000010101110010100010100101100100000011010010011001010011000101001011000011001000010101000000111011100011000111110011010101101111110101010001100011001100101011101011111011111111000110100001110001110111010011101111101100110010010001000110101101100111101010110100100111000000001010110100111111111111001101110010111101010001100010011110100100011101011110110111111110000100011011001011110011010111100101001001101110100111011101001101011111111000111111010000101000011110111110010001110001010000100001011000111000101111010000111011000010110101001011101111010000000110011111101010110010011111100'
 ),
-     );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dist_cinclude.pl b/test_regress/t/t_dist_cinclude.pl
index f264c5cd7..b6585d475 100755
--- a/test_regress/t/t_dist_cinclude.pl
+++ b/test_regress/t/t_dist_cinclude.pl
@@ -9,11 +9,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 
 use IO::File;
 
+scenarios(dist => 1);
+
 my $root = "..";
 my $Debug;
 
 if (!-r "$root/.git") {
-    $Self->skip("Not in a git repository");
+    skip("Not in a git repository");
 } else {
     ### Must trim output before and after our file list
     my $files = `cd $root && git ls-files --exclude-standard`;
@@ -47,7 +49,7 @@ if (!-r "$root/.git") {
     }
 
     if (keys %names) {
-	$Self->error("Files like stdint.h instead of cstdint: ",join(' ',sort keys %names));
+        error("Files like stdint.h instead of cstdint: ",join(' ',sort keys %names));
     }
 }
 
diff --git a/test_regress/t/t_dist_fixme.pl b/test_regress/t/t_dist_fixme.pl
index bfd92c746..92256ce87 100755
--- a/test_regress/t/t_dist_fixme.pl
+++ b/test_regress/t/t_dist_fixme.pl
@@ -9,25 +9,27 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 
 use IO::File;
 
+scenarios(dist => 1);
+
 my $root = "..";
 my $Debug;
 
 if (!-r "$root/.git") {
-    $Self->skip("Not in a git repository");
+    skip("Not in a git repository");
 } else {
     ### Must trim output before and after our file list
     my $files = `cd $root && git ls-files --exclude-standard`;
     print "ST $files\n" if $Debug;
     $files =~ s/\s+/ /g;
-    my $cmd = "cd $root && fgrep -n FIX"."ME $files | sort | grep -v t_dist_fixme";
+    my $cmd = "cd $root && grep -n -P '(FIX"."ME|BO"."ZO)' $files | sort";
     my $grep = `$cmd`;
     print "$grep\n";
     if ($grep ne "") {
-	my %names;
-	foreach my $line (split /\n/, $grep) {
-	    $names{$1} = 1 if $line =~ /^([^:]+)/;
-	}
-	$Self->error("Files with FIX"."MEs: ",join(' ',sort keys %names));
+        my %names;
+        foreach my $line (split /\n/, $grep) {
+            $names{$1} = 1 if $line =~ /^([^:]+)/;
+        }
+        error("Files with FIX"."MEs: ",join(' ',sort keys %names));
     }
 }
 
diff --git a/test_regress/t/t_dist_install.pl b/test_regress/t/t_dist_install.pl
index 347b9ff39..90a2679c2 100755
--- a/test_regress/t/t_dist_install.pl
+++ b/test_regress/t/t_dist_install.pl
@@ -9,21 +9,23 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 
 use Cwd;
 
+scenarios(dist => 1);
+
 my $root = "..";
 my $Debug;
 
 if (!-r "$root/.git") {
-    $Self->skip("Not in a git repository");
+    skip("Not in a git repository");
 } else {
     my $cwd = getcwd();
     my $destdir = "$cwd/".$Self->{obj_dir};
     # Start clean
-    $Self->run(cmd=>["rm -rf $destdir && mkdir -p $destdir"],
-               check_finished=>0);
+    run(cmd => ["rm -rf $destdir && mkdir -p $destdir"],
+        check_finished => 0);
     # Install into temp area
     print "Install...\n";
-    $Self->run(cmd=>["cd $root && make DESTDIR=$destdir install-all"],
-               check_finished=>0);
+    run(cmd => ["cd $root && make DESTDIR=$destdir install-all"],
+        check_finished => 0);
 
     # Check we can run a test
     # Unfortunately the prefix was hardcoded in the exec at a different place,
@@ -32,20 +34,20 @@ if (!-r "$root/.git") {
 
     # Uninstall
     print "Uninstall...\n";
-    $Self->run(cmd=>["cd $root && make DESTDIR=$destdir uninstall"],
-               check_finished=>0);
+    run(cmd => ["cd $root && make DESTDIR=$destdir uninstall"],
+        check_finished => 0);
 
     # Check empty
     my @files;
     $finds = `find $destdir -type f -print`;
     foreach my $file (split /\n/, $finds) {
-	next if $file =~ /\.status/;  # Made by driver.pl, not Verilator
-	print "\tLEFT:  $file\n";
-	$file =~ s!^$cwd!.!;
-	push @files, $file;
+        next if $file =~ /\.status/;  # Made by driver.pl, not Verilator
+        print "\tLEFT:  $file\n";
+        $file =~ s!^$cwd!.!;
+        push @files, $file;
     }
     if ($#files >= 0) {
-	$Self->error("Uninstall missed files: ",join(' ',@files));
+        error("Uninstall missed files: ",join(' ',@files));
     }
 }
 
diff --git a/test_regress/t/t_dist_manifest.pl b/test_regress/t/t_dist_manifest.pl
index c04eaea6a..7bc4d0462 100755
--- a/test_regress/t/t_dist_manifest.pl
+++ b/test_regress/t/t_dist_manifest.pl
@@ -7,6 +7,8 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(dist => 1);
+
 my $root = "..";
 my $Debug;
 
@@ -24,10 +26,10 @@ my %file_regexps;
 my $skip = file_contents("$root/MANIFEST.SKIP");
 foreach my $file (sort keys %files) {
     foreach my $skip (split /\s+/,$skip) {
-	if ($file =~ /$skip/) {
-	    $files{$file} |= 4;
-	    $file_regexps{$file} = $skip;
-	}
+        if ($file =~ /$skip/) {
+            $files{$file} |= 4;
+            $file_regexps{$file} = $skip;
+        }
     }
 }
 
@@ -38,24 +40,24 @@ foreach my $file (sort keys %files) {
     my $skip = $files{$file}&4;
 
     print +(($tar ? "TAR ":"    ")
-	    .($dir ? "DIR ":"    ")
-	    .($skip ? "SKIP ":"     ")
-	    ."  $file\n") if $Debug;
+            .($dir ? "DIR ":"    ")
+            .($skip ? "SKIP ":"     ")
+            ."  $file\n") if $Debug;
 
     if ($dir && !$tar && !$skip) {
-	$warns{$file} = "File not in manifest or MANIFEST.SKIP: $file";
+        $warns{$file} = "File not in manifest or MANIFEST.SKIP: $file";
     } elsif (!$dir && $tar && !$skip) {
-	$warns{$file} = "File in manifest, but not directory: $file";
+        $warns{$file} = "File in manifest, but not directory: $file";
     } elsif ($dir && $tar && $skip) {
-	$warns{$file} = "File in manifest and also MANIFEST.SKIP, too general skip regexp '$file_regexps{$file}'?: $file";
+        $warns{$file} = "File in manifest and also MANIFEST.SKIP, too general skip regexp '$file_regexps{$file}'?: $file";
     }
 }
 
 if (keys %warns) {
     # First warning lists everything as that's shown in the driver summary
-    $Self->error("Files mismatch with manifest: ",join(' ',sort keys %warns));
+    error("Files mismatch with manifest: ",join(' ',sort keys %warns));
     foreach my $file (sort keys %warns) {
-	$Self->error($warns{$file});
+        error($warns{$file});
     }
 }
 
@@ -71,8 +73,8 @@ sub get_manifest_files {
     print "MF $manifest_files\n" if $Self->{verbose};
     my %files;
     foreach my $file (split /\s+/,$manifest_files) {
-	next if $file eq '';
-	$files{$file} |= 1;
+        next if $file eq '';
+        $files{$file} |= 1;
     }
     return \%files;
 }
diff --git a/test_regress/t/t_dist_portability.pl b/test_regress/t/t_dist_portability.pl
index 48a0cee84..036925c5e 100755
--- a/test_regress/t/t_dist_portability.pl
+++ b/test_regress/t/t_dist_portability.pl
@@ -9,11 +9,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 
 use IO::File;
 
+scenarios(dist => 1);
+
 my $root = "..";
 my $Debug;
 
 if (!-r "$root/.git") {
-    $Self->skip("Not in a git repository");
+    skip("Not in a git repository");
 } else {
     uint();
     printfll();
@@ -44,7 +46,7 @@ sub uint {
 	}
     }
     if (keys %names) {
-	$Self->error("Files with uint32*_t instead of vluint32s: ",join(' ',sort keys %names));
+        error("Files with uint32*_t instead of vluint32s: ",join(' ',sort keys %names));
     }
 }
 
@@ -65,7 +67,7 @@ sub printfll {
 	}
     }
     if (keys %names) {
-	$Self->error("Files with %ll instead of VL_PRI64: ",join(' ',sort keys %names));
+        error("Files with %ll instead of VL_PRI64: ",join(' ',sort keys %names));
     }
 }
 
@@ -83,7 +85,7 @@ sub cstr {
 	}
     }
     if (keys %names) {
-	$Self->error("Files with potential c_str() lifetime issue: ",join(' ',sort keys %names));
+        error("Files with potential c_str() lifetime issue: ",join(' ',sort keys %names));
     }
 }
 
@@ -102,7 +104,7 @@ sub vsnprintf {
 	}
     }
     if (keys %names) {
-	$Self->error("Files with vsnprintf, use VL_VSNPRINTF: ",join(' ',sort keys %names));
+        error("Files with vsnprintf, use VL_VSNPRINTF: ",join(' ',sort keys %names));
     }
 }
 
diff --git a/test_regress/t/t_dist_tabs.pl b/test_regress/t/t_dist_tabs.pl
index 142e5eb51..90915eaf1 100755
--- a/test_regress/t/t_dist_tabs.pl
+++ b/test_regress/t/t_dist_tabs.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(dist => 1);
+
 my $root = "..";
 
 if (!-r "$root/.git") {
-    $Self->skip("Not in a git repository");
+    skip("Not in a git repository");
 } else {
     ### Must trim output before and after our file list
     my %warns;
@@ -46,9 +48,9 @@ if (!-r "$root/.git") {
     }
     if (keys %warns) {
         # First warning lists everything as that's shown in the driver summary
-        $Self->error($summary." ",join(' ',sort keys %warns));
+        error($summary." ",join(' ',sort keys %warns));
         foreach my $file (sort keys %warns) {
-            $Self->error($warns{$file});
+            error($warns{$file});
         }
     }
 }
diff --git a/test_regress/t/t_dist_untracked.pl b/test_regress/t/t_dist_untracked.pl
index 839454bbf..a0e8e57be 100755
--- a/test_regress/t/t_dist_untracked.pl
+++ b/test_regress/t/t_dist_untracked.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(dist => 1);
+
 my $root = "..";
 my $Debug;
 
 if (!-r "$root/.git") {
-    $Self->skip("Not in a git repository");
+    skip("Not in a git repository");
 } else {
     ### Must trim output before and after our file list
     my %warns;
@@ -33,9 +35,9 @@ if (!-r "$root/.git") {
     }
     if (keys %warns) {
         # First warning lists everything as that's shown in the driver summary
-        $Self->error($summary." ",join(' ',sort keys %warns));
+        error($summary." ",join(' ',sort keys %warns));
         foreach my $file (sort keys %warns) {
-            $Self->error($warns{$file});
+            error($warns{$file});
         }
     }
 }
diff --git a/test_regress/t/t_dist_whitespace.pl b/test_regress/t/t_dist_whitespace.pl
index 925b5a5d6..35a72b280 100755
--- a/test_regress/t/t_dist_whitespace.pl
+++ b/test_regress/t/t_dist_whitespace.pl
@@ -7,6 +7,8 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(dist => 1);
+
 my $root = "..";
 my $Debug;
 
@@ -45,14 +47,14 @@ foreach my $file (sort keys %files) {
 if (keys %warns) {
     # First warning lists everything as that's shown in the driver summary
     if ($ENV{HARNESS_UPDATE_GOLDEN}) {
-	$Self->error("Updated files with whitespace errors: ",join(' ',sort keys %warns));
-	$Self->error("To auto-fix: HARNESS_UPDATE_GOLDEN=1 {command} or --golden");
+        error("Updated files with whitespace errors: ",join(' ',sort keys %warns));
+        error("To auto-fix: HARNESS_UPDATE_GOLDEN=1 {command} or --golden");
     } else {
-	$Self->error("Files have whitespace errors: ",join(' ',sort keys %warns));
-	$Self->error("To auto-fix: HARNESS_UPDATE_GOLDEN=1 {command} or --golden");
+        error("Files have whitespace errors: ",join(' ',sort keys %warns));
+        error("To auto-fix: HARNESS_UPDATE_GOLDEN=1 {command} or --golden");
     }
     foreach my $file (sort keys %warns) {
-	$Self->error($warns{$file});
+        error($warns{$file});
     }
 }
 
diff --git a/test_regress/t/t_dos.pl b/test_regress/t/t_dos.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_dos.pl
+++ b/test_regress/t/t_dos.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_2exp_bad.pl b/test_regress/t/t_dpi_2exp_bad.pl
index b49860a7a..e8f108ede 100755
--- a/test_regress/t/t_dpi_2exp_bad.pl
+++ b/test_regress/t/t_dpi_2exp_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_dpi_2exp_bad.v:11: Function was already DPI Exported, duplicate not allowed: dpix_twice
 %Error: Exiting due to .*'
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_accessors.pl b/test_regress/t/t_dpi_accessors.pl
index 4c69d787f..d2741cc06 100755
--- a/test_regress/t/t_dpi_accessors.pl
+++ b/test_regress/t/t_dpi_accessors.pl
@@ -10,13 +10,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # 8-Mar-2012: Modifications for this test contributed by Jeremy Bennett and
 # Jie Xu.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     make_top_shell   => 0,
     make_main        => 0,
     verilator_flags2 => ["-Wno-BLKANDNBLK -language 1800-2005 --exe $Self->{t_dir}/$Self->{name}.cpp"], );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_dpi_context.pl b/test_regress/t/t_dpi_context.pl
index 016a5768a..10cc5c36c 100755
--- a/test_regress/t/t_dpi_context.pl
+++ b/test_regress/t/t_dpi_context.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["t/t_dpi_context_c.cpp"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    v_flags2 => ["t/t_dpi_context_c.cpp"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_context_noopt.pl b/test_regress/t/t_dpi_context_noopt.pl
index d02a1a2b4..ed5d502ed 100755
--- a/test_regress/t/t_dpi_context_noopt.pl
+++ b/test_regress/t/t_dpi_context_noopt.pl
@@ -7,16 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_dpi_context.v");
 
-compile (
-	 v_flags2 => ["t/t_dpi_context_c.cpp"],
-	 verilator_flags2 => [$Self->{v3}?"-O0":""],
-	 );
+compile(
+    v_flags2 => ["t/t_dpi_context_c.cpp"],
+    verilator_flags2 => [$Self->{vlt}?"-O0":""],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_display.pl b/test_regress/t/t_dpi_display.pl
index f2c032f05..4999351dd 100755
--- a/test_regress/t/t_dpi_display.pl
+++ b/test_regress/t/t_dpi_display.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["t/t_dpi_display_c.cpp"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 expect=>quotemeta(
+compile(
+    v_flags2 => ["t/t_dpi_display_c.cpp"],
+    );
+
+execute(
+    check_finished => 1,
+    expect => quotemeta(
 q{dpii_display_call: ''
 dpii_display_call: 'c'
 dpii_display_call: 'co'
diff --git a/test_regress/t/t_dpi_dup_bad.pl b/test_regress/t/t_dpi_dup_bad.pl
index f5bd35556..071d02ca0 100755
--- a/test_regress/t/t_dpi_dup_bad.pl
+++ b/test_regress/t/t_dpi_dup_bad.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_dpi_dup_bad.v:\d+: Duplicate declaration of DPI function with different formal arguments: t.oth_f_int2
 %Error: t/t_dpi_dup_bad.v:\d+: ... New prototype:      pure int dpii_fa_bit \(int, int\)
 %Error: t/t_dpi_dup_bad.v:\d+: ... Original prototype: int dpii_fa_bit \(int\)
 %Error: Exiting due to .*'
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_exp_bad.pl b/test_regress/t/t_dpi_exp_bad.pl
index eb555643e..eb1b354e2 100755
--- a/test_regress/t/t_dpi_exp_bad.pl
+++ b/test_regress/t/t_dpi_exp_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>$Self->{v3},
-    expect=>
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_dpi_exp_bad.v:\d+: DPI functions cannot return > 32 bits or four-state; use a two-state type or task instead: dpix_f_bit48__Vfuncrtn
 %Error: Exiting due to .*'
     );
diff --git a/test_regress/t/t_dpi_export.pl b/test_regress/t/t_dpi_export.pl
index 2e51f6dff..a665b7335 100755
--- a/test_regress/t/t_dpi_export.pl
+++ b/test_regress/t/t_dpi_export.pl
@@ -7,17 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-#	irun -sv top.v t_dpi_export.v -cpost t_dpi_export_c.c -end
+#       irun -sv top.v t_dpi_export.v -cpost t_dpi_export_c.c -end
 
-compile (
-	 # Amazingly VCS, NC and Verilator all just accept the C file here!
-	 v_flags2 => ["t/t_dpi_export_c.cpp"],
-	 verilator_flags2 => ["-Wall -Wno-DECLFILENAME -no-l2name"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    # Amazingly VCS, NC and Verilator all just accept the C file here!
+    v_flags2 => ["t/t_dpi_export_c.cpp"],
+    verilator_flags2 => ["-Wall -Wno-DECLFILENAME -no-l2name"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_imp_gen.pl b/test_regress/t/t_dpi_imp_gen.pl
index 15fc697c3..7232ad5ee 100755
--- a/test_regress/t/t_dpi_imp_gen.pl
+++ b/test_regress/t/t_dpi_imp_gen.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["t/t_dpi_imp_gen_c.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_dpi_import.pl b/test_regress/t/t_dpi_import.pl
index 115378628..ce88e2ad0 100755
--- a/test_regress/t/t_dpi_import.pl
+++ b/test_regress/t/t_dpi_import.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 # Amazingly VCS, NC and Verilator all just accept the C file here!
-	 v_flags2 => ["t/t_dpi_import_c.cpp"],
-	 verilator_flags2 => ["-Wall -Wno-DECLFILENAME"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    # Amazingly VCS, NC and Verilator all just accept the C file here!
+    v_flags2 => ["t/t_dpi_import_c.cpp"],
+    verilator_flags2 => ["-Wall -Wno-DECLFILENAME"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_lib.pl b/test_regress/t/t_dpi_lib.pl
index 28a0c4bb3..292f84bce 100755
--- a/test_regress/t/t_dpi_lib.pl
+++ b/test_regress/t/t_dpi_lib.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["t/t_dpi_lib_c.cpp"],
     verilator_flags2 => ["-Wall -Wno-DECLFILENAME"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_dpi_logic_bad.pl b/test_regress/t/t_dpi_logic_bad.pl
index 69732372e..15509c064 100755
--- a/test_regress/t/t_dpi_logic_bad.pl
+++ b/test_regress/t/t_dpi_logic_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>$Self->{v3},
-    expect=>
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_dpi_logic_bad.v:\d+: DPI function may not return type BASICDTYPE \'logic\' \(IEEE 2017 35.5.5\)
 %Error: Exiting due to .*'
     );
diff --git a/test_regress/t/t_dpi_name_bad.pl b/test_regress/t/t_dpi_name_bad.pl
index c39aad5bd..18d746405 100755
--- a/test_regress/t/t_dpi_name_bad.pl
+++ b/test_regress/t/t_dpi_name_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_dpi_name_bad.v:\d+: DPI function has illegal characters in C identifier name: badly.named
 %Error: Exiting due to .*'
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_open.pl b/test_regress/t/t_dpi_open.pl
index 08f291fbe..c4ca90723 100755
--- a/test_regress/t/t_dpi_open.pl
+++ b/test_regress/t/t_dpi_open.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["t/t_dpi_open_c.cpp"],
     verilator_flags2 => ["-Wall -Wno-DECLFILENAME -unroll-count 1"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_dpi_openfirst.pl b/test_regress/t/t_dpi_openfirst.pl
index cb699b0e8..0e6e42ea9 100755
--- a/test_regress/t/t_dpi_openfirst.pl
+++ b/test_regress/t/t_dpi_openfirst.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["t/t_dpi_openfirst_c.cpp"],
     verilator_flags2 => ["-Wall -Wno-DECLFILENAME"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_dpi_openreg_bad.pl b/test_regress/t/t_dpi_openreg_bad.pl
index d004a23ed..f02701726 100755
--- a/test_regress/t/t_dpi_openreg_bad.pl
+++ b/test_regress/t/t_dpi_openreg_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>$Self->{v3},
-    expect=>
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_dpi_openreg_bad.v:\d+: Unsized/open arrays \(\'\[\]\'\) are only supported in DPI imports
 %Error: t/t_dpi_openreg_bad.v:\d+: Unsized/open arrays \(\'\[\]\'\) are only supported in DPI imports
 %Error: Exiting due to .*'
diff --git a/test_regress/t/t_dpi_qw.pl b/test_regress/t/t_dpi_qw.pl
index cd7f6f5d3..5f46d7150 100755
--- a/test_regress/t/t_dpi_qw.pl
+++ b/test_regress/t/t_dpi_qw.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["t/t_dpi_qw_c.cpp"],
-	 verilator_flags2 => ["-Wall -Wno-DECLFILENAME -no-l2name"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    v_flags2 => ["t/t_dpi_qw_c.cpp"],
+    verilator_flags2 => ["-Wall -Wno-DECLFILENAME -no-l2name"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_shortcircuit.pl b/test_regress/t/t_dpi_shortcircuit.pl
index 3b0bfdcb5..d065fdda9 100755
--- a/test_regress/t/t_dpi_shortcircuit.pl
+++ b/test_regress/t/t_dpi_shortcircuit.pl
@@ -7,17 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, bug413 short circuit");
+scenarios(simulator => 1);
+$Self->{vlt} and unsupported("Verilator unsupported, bug413 short circuit");
 
-compile (
-	 # Amazingly VCS, NC and Verilator all just accept the C file here!
-	 v_flags2 => ["t/t_dpi_shortcircuit_c.cpp"],
-	 verilator_flags2 => ["-Wno-DECLFILENAME"],
-	 );
+compile(
+    # Amazingly VCS, NC and Verilator all just accept the C file here!
+    v_flags2 => ["t/t_dpi_shortcircuit_c.cpp"],
+    verilator_flags2 => ["-Wno-DECLFILENAME"],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_shortcircuit2.pl b/test_regress/t/t_dpi_shortcircuit2.pl
index 216c1b691..c076932ad 100755
--- a/test_regress/t/t_dpi_shortcircuit2.pl
+++ b/test_regress/t/t_dpi_shortcircuit2.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 # Amazingly VCS, NC and Verilator all just accept the C file here!
-	 v_flags2 => ["t/t_dpi_shortcircuit_c.cpp"],
-	 verilator_flags2 => ["-Wno-DECLFILENAME"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    # Amazingly VCS, NC and Verilator all just accept the C file here!
+    v_flags2 => ["t/t_dpi_shortcircuit_c.cpp"],
+    verilator_flags2 => ["-Wno-DECLFILENAME"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_string.pl b/test_regress/t/t_dpi_string.pl
index ae6cbdd77..9e6086334 100755
--- a/test_regress/t/t_dpi_string.pl
+++ b/test_regress/t/t_dpi_string.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    	 v_flags2 => ["t/t_dpi_string_c.cpp"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    v_flags2 => ["t/t_dpi_string_c.cpp"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_sys.pl b/test_regress/t/t_dpi_sys.pl
index 1e96cf6dc..baee7849c 100755
--- a/test_regress/t/t_dpi_sys.pl
+++ b/test_regress/t/t_dpi_sys.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    	 v_flags2 => ["t/t_dpi_sys_c.cpp"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    v_flags2 => ["t/t_dpi_sys_c.cpp"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_dpi_vams.pl b/test_regress/t/t_dpi_vams.pl
index 653add643..66b07eadf 100755
--- a/test_regress/t/t_dpi_vams.pl
+++ b/test_regress/t/t_dpi_vams.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     make_top_shell => 0,
     make_main => 0,
     verilator_flags2 => ["--exe","$Self->{t_dir}/$Self->{name}.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_dpi_var.pl b/test_regress/t/t_dpi_var.pl
index e674bcf17..699b48d9e 100755
--- a/test_regress/t/t_dpi_var.pl
+++ b/test_regress/t/t_dpi_var.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe --no-l2name $Self->{t_dir}/t_dpi_var.cpp"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe --no-l2name $Self->{t_dir}/t_dpi_var.cpp"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_embed1.pl b/test_regress/t/t_embed1.pl
index 7d6eb6d3c..9bdb42848 100755
--- a/test_regress/t/t_embed1.pl
+++ b/test_regress/t/t_embed1.pl
@@ -9,6 +9,8 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 
 use File::Spec;
 
+scenarios(simulator => 1);
+
 my $self = $Self;
 my $child_dir = "$Self->{obj_dir}_child";
 mkdir $child_dir;
@@ -16,35 +18,35 @@ mkdir $child_dir;
 # Compile the child
 {
     my @cmdargs = $Self->compile_vlt_flags
-	(VM_PREFIX => "$Self->{VM_PREFIX}_child",
-	 top_filename => "$Self->{name}_child.v",
-	 verilator_flags => ["-cc", "-Mdir", "${child_dir}", "--debug-check"],
-	);
+        (VM_PREFIX => "$Self->{VM_PREFIX}_child",
+         top_filename => "$Self->{name}_child.v",
+         verilator_flags => ["-cc", "-Mdir", "${child_dir}", "--debug-check"],
+        );
 
-    $Self->run(logfile=>"${child_dir}/vlt_compile.log",
-               cmd=>\@cmdargs);
+    run(logfile => "${child_dir}/vlt_compile.log",
+        cmd => \@cmdargs);
 
-    $Self->run(logfile=>"${child_dir}/vlt_gcc.log",
-               cmd=>["cd ${child_dir} && ",
-                     "make", "-f".getcwd()."/Makefile_obj",
-                     "CPPFLAGS_DRIVER=-D".uc($self->{name}),
-                     ($opt_verbose ? "CPPFLAGS_DRIVER2=-DTEST_VERBOSE=1":""),
-                     "MAKE_MAIN=0",
-                     "VM_PREFIX=$self->{VM_PREFIX}_child",
-                     "V$self->{name}_child__ALL.a",  # bypass default rule, make archive
-                     ($param{make_flags}||""),
-               ]);
+    run(logfile => "${child_dir}/vlt_gcc.log",
+        cmd => ["cd ${child_dir} && ",
+                "make", "-f".getcwd()."/Makefile_obj",
+                "CPPFLAGS_DRIVER=-D".uc($self->{name}),
+                ($opt_verbose ? "CPPFLAGS_DRIVER2=-DTEST_VERBOSE=1":""),
+                "MAKE_MAIN=0",
+                "VM_PREFIX=$self->{VM_PREFIX}_child",
+                "V$self->{name}_child__ALL.a",  # bypass default rule, make archive
+                ($param{make_flags}||""),
+        ]);
 }
 
 # Compile the parent (might be with other than verilator)
-compile (
+compile(
     v_flags2 => [File::Spec->rel2abs("${child_dir}/V$self->{name}_child__ALL.a"),
-		 # TODO would be nice to have this in embedded archive
-		 "t/t_embed1_c.cpp"],
+                 # TODO would be nice to have this in embedded archive
+                 "t/t_embed1_c.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_emit_constw.pl b/test_regress/t/t_emit_constw.pl
index 48fe87ce0..ed09e4347 100755
--- a/test_regress/t/t_emit_constw.pl
+++ b/test_regress/t/t_emit_constw.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ['--Ox'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ['--Ox'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_emit_memb_limit.pl b/test_regress/t/t_emit_memb_limit.pl
index 54f65baa6..713d6af9e 100755
--- a/test_regress/t/t_emit_memb_limit.pl
+++ b/test_regress/t/t_emit_memb_limit.pl
@@ -8,6 +8,8 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Version 2.0.
 use IO::File;
 
+scenarios(simulator => 1);
+
 sub gen {
     my $filename = shift;
     my $n = shift;
@@ -38,12 +40,12 @@ top_filename("$Self->{obj_dir}/t_emit_memb_limit.v");
 # Current limit is 50, so want to test at least 50*50 cases
 gen($Self->{top_filename}, 6000);
 
-compile (
+compile(
     verilator_flags2=>["-x-assign fast --x-initial fast"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 file_grep ("$Self->{obj_dir}/$Self->{VM_PREFIX}.h", qr/struct \{/);
diff --git a/test_regress/t/t_enum.pl b/test_regress/t/t_enum.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_enum.pl
+++ b/test_regress/t/t_enum.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_enum_func.pl b/test_regress/t/t_enum_func.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_enum_func.pl
+++ b/test_regress/t/t_enum_func.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_enum_int.pl b/test_regress/t/t_enum_int.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_enum_int.pl
+++ b/test_regress/t/t_enum_int.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_enum_large_methods.pl b/test_regress/t/t_enum_large_methods.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_enum_large_methods.pl
+++ b/test_regress/t/t_enum_large_methods.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_enum_name2.pl b/test_regress/t/t_enum_name2.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_enum_name2.pl
+++ b/test_regress/t/t_enum_name2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_enum_name3.pl b/test_regress/t/t_enum_name3.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_enum_name3.pl
+++ b/test_regress/t/t_enum_name3.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_enum_overlap_bad.pl b/test_regress/t/t_enum_overlap_bad.pl
index 307c0c994..08bf8eb06 100755
--- a/test_regress/t/t_enum_overlap_bad.pl
+++ b/test_regress/t/t_enum_overlap_bad.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_enum_overlap_bad.v:\d+: Overlapping enumeration value: e1b
 %Error: t/t_enum_overlap_bad.v:\d+: ... Location of original declaration
 %Error: Exiting due to',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_enum_public.pl b/test_regress/t/t_enum_public.pl
index 4408cbf72..0560d989d 100755
--- a/test_regress/t/t_enum_public.pl
+++ b/test_regress/t/t_enum_public.pl
@@ -7,19 +7,21 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 if ($Self->{vlt}) {
-    compile (
-	verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
-	make_top_shell => 0,
-	make_main => 0,
-	);
+    compile(
+        verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
+        make_top_shell => 0,
+        make_main => 0,
+        );
 } else {
-    compile (
-	);
+    compile(
+        );
 }
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_enum_type_methods.pl b/test_regress/t/t_enum_type_methods.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_enum_type_methods.pl
+++ b/test_regress/t/t_enum_type_methods.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_enum_type_pins.pl b/test_regress/t/t_enum_type_pins.pl
index fda118f1a..0b6418428 100755
--- a/test_regress/t/t_enum_type_pins.pl
+++ b/test_regress/t/t_enum_type_pins.pl
@@ -7,14 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
 # Not yet working on Verilator
-$Self->{vlt} and $Self->unsupported("Verilator unsupported");
+$Self->{vlt} and unsupported("Verilator unsupported");
 
-compile (
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_enumeration.pl b/test_regress/t/t_enumeration.pl
index 6d5abb42b..7ea54cef9 100755
--- a/test_regress/t/t_enumeration.pl
+++ b/test_regress/t/t_enumeration.pl
@@ -7,14 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, bug460");
+scenarios(simulator => 1);
+$Self->{vlt} and unsupported("Verilator unsupported, bug460");
 
-compile (
-	 );
+compile(
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_extend.pl b/test_regress/t/t_extend.pl
index c4a78b37b..1be18a66c 100755
--- a/test_regress/t/t_extend.pl
+++ b/test_regress/t/t_extend.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_extend_class.pl b/test_regress/t/t_extend_class.pl
index f2d6b5986..6da737e5a 100755
--- a/test_regress/t/t_extend_class.pl
+++ b/test_regress/t/t_extend_class.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     make_flags => "CPPFLAGS_ADD=-I$Self->{t_dir}",
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_final.pl b/test_regress/t/t_final.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_final.pl
+++ b/test_regress/t/t_final.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_flag_bboxsys.pl b/test_regress/t/t_flag_bboxsys.pl
index 28debed29..607c39a55 100755
--- a/test_regress/t/t_flag_bboxsys.pl
+++ b/test_regress/t/t_flag_bboxsys.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
-	 verilator_flags2 => ["--bbox-sys"],
-	 );
+compile(
+    verilator_flags2 => ["--bbox-sys"],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_csplit.pl b/test_regress/t/t_flag_csplit.pl
index 80675f6e3..334edeb17 100755
--- a/test_regress/t/t_flag_csplit.pl
+++ b/test_regress/t/t_flag_csplit.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--trace --output-split 1 --output-split-cfuncs 1"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 my $got1;
@@ -22,7 +22,7 @@ foreach my $file (glob("$Self->{obj_dir}/*.cpp")) {
     $got1 = 1 if $file =~ /__1/;
     check($file);
 }
-$got1 or $Self->error("No __1 split file found");
+$got1 or error("No __1 split file found");
 
 ok(1);
 1;
@@ -32,7 +32,7 @@ sub check {
     my $filename = shift;
     my $size = -s $filename;
     printf "  File %6d  %s\n", $size, $filename if $Self->{verbose};
-    my $fh = IO::File->new("<$filename") or $Self->error("$! $filenme");
+    my $fh = IO::File->new("<$filename") or error("$! $filenme");
     my @funcs;
     while (defined (my $line = $fh->getline)) {
 	if ($line =~ /^(void|IData)\s+(.*::.*)/) {
@@ -50,6 +50,6 @@ sub check {
 	}
     }
     if ($#funcs > 0) {
-	$Self->error("Split had multiple functions in $filename\n\t".join("\n\t",@funcs));
+        error("Split had multiple functions in $filename\n\t".join("\n\t",@funcs));
     }
 }
diff --git a/test_regress/t/t_flag_debug_noleak.pl b/test_regress/t/t_flag_debug_noleak.pl
index 97e7d9366..2b48967e4 100755
--- a/test_regress/t/t_flag_debug_noleak.pl
+++ b/test_regress/t/t_flag_debug_noleak.pl
@@ -7,9 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
+compile(
     v_flags2 => ["--debug --no-debug-leak"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_flag_define.pl b/test_regress/t/t_flag_define.pl
index 0ecc0c0ba..59d1d460b 100755
--- a/test_regress/t/t_flag_define.pl
+++ b/test_regress/t/t_flag_define.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(vlt => 1);
+
+compile(
     v_flags2 => ["-f t/t_flag_define.vc"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_flag_f.pl b/test_regress/t/t_flag_f.pl
index 95b6413d6..d153e1bfe 100755
--- a/test_regress/t/t_flag_f.pl
+++ b/test_regress/t/t_flag_f.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["-f t/t_flag_f.vc"],
-	 );
+scenarios(vlt => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    v_flags2 => ["-f t/t_flag_f.vc"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_fi.pl b/test_regress/t/t_flag_fi.pl
index 4191f83b6..8acd952d7 100755
--- a/test_regress/t/t_flag_fi.pl
+++ b/test_regress/t/t_flag_fi.pl
@@ -7,17 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     v_flags2 => ["-FI $Self->{t_dir}/t_flag_fi_h.h",
-		 "--exe $Self->{t_dir}/$Self->{name}.cpp"],
+                 "--exe $Self->{t_dir}/$Self->{name}.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_flag_future.pl b/test_regress/t/t_flag_future.pl
index b4298f847..056d0c358 100755
--- a/test_regress/t/t_flag_future.pl
+++ b/test_regress/t/t_flag_future.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(vlt => 1);
+
+compile(
     make_top_shell => 0,
     make_main => 0,
     verilator_flags2 => [qw(--lint-only -Wfuture-FUTURE1 -Wfuture-FUTURE2)],
diff --git a/test_regress/t/t_flag_getenv.pl b/test_regress/t/t_flag_getenv.pl
index 37a20b3ac..46a0f5603 100755
--- a/test_regress/t/t_flag_getenv.pl
+++ b/test_regress/t/t_flag_getenv.pl
@@ -7,19 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
 $ENV{FOOBARTEST} = "gotit";
 
-compile (
-	 v_flags2 => ["--getenv FOOBARTEST"],
-	 expect=>
+compile(
+    v_flags2 => ["--getenv FOOBARTEST"],
+    expect =>
 'gotit
 ',
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_make_gcc => 0,
-	 );
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_make_gcc => 0,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_language.pl b/test_regress/t/t_flag_language.pl
index 7e59fbdca..f0482a0e5 100755
--- a/test_regress/t/t_flag_language.pl
+++ b/test_regress/t/t_flag_language.pl
@@ -1,13 +1,21 @@
 #!/usr/bin/perl
 if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2008 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
 
-compile (
-	 verilator_flags2 => ['--language 1364-2001'],
-	 );
+scenarios(vlt => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ['--language 1364-2001'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_ldflags.pl b/test_regress/t/t_flag_ldflags.pl
index a1f016a71..dd0a85cd2 100755
--- a/test_regress/t/t_flag_ldflags.pl
+++ b/test_regress/t/t_flag_ldflags.pl
@@ -7,30 +7,30 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-$Self->run(cmd=>["cd $Self->{obj_dir}"
-                 ." && c++ -c ../../t/t_flag_ldflags_a.cpp"
-                 ." && ar r t_flag_ldflags_a.a t_flag_ldflags_a.o"
-                 ." && ranlib t_flag_ldflags_a.a "],
-           check_finished=>0);
-$Self->run(cmd=>["cd $Self->{obj_dir}"
-                 ." && c++ -fPIC -c ../../t/t_flag_ldflags_so.cpp"
-                 ." && c++ -shared -o t_flag_ldflags_so.so -lc t_flag_ldflags_so.o"],
-           check_finished=>0);
+run(cmd => ["cd $Self->{obj_dir}"
+            ." && c++ -c ../../t/t_flag_ldflags_a.cpp"
+            ." && ar r t_flag_ldflags_a.a t_flag_ldflags_a.o"
+            ." && ranlib t_flag_ldflags_a.a "],
+    check_finished => 0);
+run(cmd => ["cd $Self->{obj_dir}"
+            ." && c++ -fPIC -c ../../t/t_flag_ldflags_so.cpp"
+            ." && c++ -shared -o t_flag_ldflags_so.so -lc t_flag_ldflags_so.o"],
+    check_finished => 0);
 
-compile (
-	 # Pass multiple -D's so we check quoting works properly
-    	 v_flags2 => ["-CFLAGS '-DCFLAGS_FROM_CMDLINE -DCFLAGS2_FROM_CMDLINE' ",
-		      "t/t_flag_ldflags_c.cpp",
-		      "t_flag_ldflags_a.a",
-		      "t_flag_ldflags_so.so",],
-	 );
+compile(
+    # Pass multiple -D's so we check quoting works properly
+    v_flags2 => ["-CFLAGS '-DCFLAGS_FROM_CMDLINE -DCFLAGS2_FROM_CMDLINE' ",
+                 "t/t_flag_ldflags_c.cpp",
+                 "t_flag_ldflags_a.a",
+                 "t_flag_ldflags_so.so",],
+    );
 
-execute (
-	 check_finished=>1,
-	 run_env => "LD_LIBRARY_PATH=$Self->{obj_dir}",
-     );
+execute(
+    check_finished => 1,
+    run_env => "LD_LIBRARY_PATH=$Self->{obj_dir}",
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_lib.pl b/test_regress/t/t_flag_lib.pl
index 38f955272..70632d38a 100755
--- a/test_regress/t/t_flag_lib.pl
+++ b/test_regress/t/t_flag_lib.pl
@@ -1,13 +1,21 @@
 #!/usr/bin/perl
 if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
 
-compile (
-	 v_flags2 => ['-v', 't/t_flag_libinc.v'],
-	 );
+scenarios(vlt => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    v_flags2 => ['-v', 't/t_flag_libinc.v'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_names.pl b/test_regress/t/t_flag_names.pl
index f5b84d9ba..150ac0668 100755
--- a/test_regress/t/t_flag_names.pl
+++ b/test_regress/t/t_flag_names.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(vlt => 1);
+
+compile(
     verilator_flags2 => ["--mod-prefix modPrefix --top-module t --l2-name l2Name"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_flag_nomod_bad.pl b/test_regress/t/t_flag_nomod_bad.pl
index bc8121154..93832c31a 100755
--- a/test_regress/t/t_flag_nomod_bad.pl
+++ b/test_regress/t/t_flag_nomod_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 '%Error: No top level module found
 %Error: Exiting due to',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_parameter.pl b/test_regress/t/t_flag_parameter.pl
index 1271079bb..2b3c896c1 100755
--- a/test_regress/t/t_flag_parameter.pl
+++ b/test_regress/t/t_flag_parameter.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(vlt => 1);
+
+compile(
     # It is not possible to put them into the options file
     v_flags2 => ['-Gstring1="\"New String\"" -pvalue+string2="\"New String\"" -f t/t_flag_parameter.vc'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_flag_relinc.pl b/test_regress/t/t_flag_relinc.pl
index 4e525dcc6..6471e8f90 100755
--- a/test_regress/t/t_flag_relinc.pl
+++ b/test_regress/t/t_flag_relinc.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
+compile(
     v_flags2 => ["--relative-includes",
-		 "--lint-only $Self->{t_dir}/t_flag_relinc_dir/chip/t_flag_relinc_sub.v"],
+                 "--lint-only $Self->{t_dir}/t_flag_relinc_dir/chip/t_flag_relinc_sub.v"],
     make_top_shell => 0,
     make_main => 0,
     verilator_make_gcc => 0,
diff --git a/test_regress/t/t_flag_skipidentical.pl b/test_regress/t/t_flag_skipidentical.pl
index 8881462db..9b05be5ee 100755
--- a/test_regress/t/t_flag_skipidentical.pl
+++ b/test_regress/t/t_flag_skipidentical.pl
@@ -7,25 +7,25 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
 {
-    compile ();
+    compile();
 
     my $outfile = "$Self->{obj_dir}/V".$Self->{name}.".cpp";
     my @oldstats = stat($outfile);
     print "Old mtime=",$oldstats[9],"\n";
-    $oldstats[9] or $Self->error("No output file found: $outfile\n");
+    $oldstats[9] or error("No output file found: $outfile\n");
 
     sleep (1);  # Or else it might take < 1 second to compile and see no diff.
 
-    compile ();
+    compile();
 
     my @newstats = stat($outfile);
     print "New mtime=",$newstats[9],"\n";
 
     ($oldstats[9] == $newstats[9])
-	or $Self->error("--skip-identical was ignored -- recompiled\n");
+        or error("--skip-identical was ignored -- recompiled\n");
 }
 
 ok(1);
diff --git a/test_regress/t/t_flag_stats.pl b/test_regress/t/t_flag_stats.pl
index c79b43f50..addaf5a47 100755
--- a/test_regress/t/t_flag_stats.pl
+++ b/test_regress/t/t_flag_stats.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     verilator_flags2 => ["--stats --stats-vars"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_flag_topmod2_bad.pl b/test_regress/t/t_flag_topmod2_bad.pl
index 4455e1d02..e749ecd73 100755
--- a/test_regress/t/t_flag_topmod2_bad.pl
+++ b/test_regress/t/t_flag_topmod2_bad.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
-	 v_flags2 => ["--top-module a "],
-	 fails=>$Self->{v3},
-	 nc=>0,  # Need to get it not to give the prompt
-	 expect=>
+compile(
+    v_flags2 => ["--top-module a "],
+    fails => $Self->{vlt},
+    nc => 0,  # Need to get it not to give the prompt
+    expect =>
 '%Error: Specified --top-module \'a\' isn.t at the top level, it.s under another cell \'a_top\'
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_topmodule.pl b/test_regress/t/t_flag_topmodule.pl
index d8622fec0..8a29e5b05 100755
--- a/test_regress/t/t_flag_topmodule.pl
+++ b/test_regress/t/t_flag_topmodule.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
-	 v_flags2 => ["--top-module b "],
-	 );
+compile(
+    v_flags2 => ["--top-module b "],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_topmodule_bad.pl b/test_regress/t/t_flag_topmodule_bad.pl
index 2889e0e75..f65d2074e 100755
--- a/test_regress/t/t_flag_topmodule_bad.pl
+++ b/test_regress/t/t_flag_topmodule_bad.pl
@@ -7,18 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt => 1);
+
 top_filename("t/t_flag_topmodule.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 fails=>$Self->{v3},
-	 nc=>0,  # Need to get it not to give the prompt
-	 expect=>
+compile(
+    fails => $Self->{vlt},
+    nc => 0,  # Need to get it not to give the prompt
+    expect =>
 '%Error-MULTITOP: t/t_flag_topmodule.v:\d+: Unsupported: Multiple top level modules: .*
 %Error-MULTITOP: t/t_flag_topmodule.v:\d+: Fix, or use --top-module option to select which you want.
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_topmodule_bad2.pl b/test_regress/t/t_flag_topmodule_bad2.pl
index afcdae4f6..58f804727 100755
--- a/test_regress/t/t_flag_topmodule_bad2.pl
+++ b/test_regress/t/t_flag_topmodule_bad2.pl
@@ -7,18 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt => 1);
+
 top_filename("t/t_flag_topmodule.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 fails=>$Self->{v3},
-	 v_flags2 => ["--top-module notfound"],
-	 nc=>0,  # Need to get it not to give the prompt
-	 expect=>
+compile(
+    fails => $Self->{vlt},
+    v_flags2 => ["--top-module notfound"],
+    nc => 0,  # Need to get it not to give the prompt
+    expect =>
 '%Error: Specified --top-module \'notfound\' was not found in design.
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_topmodule_inline.pl b/test_regress/t/t_flag_topmodule_inline.pl
index 59c495cb7..71014e108 100755
--- a/test_regress/t/t_flag_topmodule_inline.pl
+++ b/test_regress/t/t_flag_topmodule_inline.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
-	 v_flags2 => ["--top-module b"],
-	 );
+compile(
+    v_flags2 => ["--top-module b"],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_werror_bad1.pl b/test_regress/t/t_flag_werror_bad1.pl
index 24ead58f9..9a952a724 100755
--- a/test_regress/t/t_flag_werror_bad1.pl
+++ b/test_regress/t/t_flag_werror_bad1.pl
@@ -7,18 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt => 1);
+
 top_filename("t/t_flag_werror.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 q{%Warning-WIDTH: t/t_flag_werror.v:\d+: Operator ASSIGNW expects 4 bits on the Assign RHS, but Assign RHS.s CONST '6'h2e' generates 6 bits.
 %Warning-WIDTH: Use .* and lint_on around source to disable this message.
 %Error: Exiting due to},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_werror_bad2.pl b/test_regress/t/t_flag_werror_bad2.pl
index c6786b573..11653d135 100755
--- a/test_regress/t/t_flag_werror_bad2.pl
+++ b/test_regress/t/t_flag_werror_bad2.pl
@@ -7,16 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt => 1);
+
 top_filename("t/t_flag_werror.v");
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 verilator_flags=> [qw(-cc -Werror-WIDTH)],
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    verilator_flags => [qw(-cc -Werror-WIDTH)],
+    expect =>
 q{%Error-WIDTH: t/t_flag_werror.v:\d+: Operator ASSIGNW expects 4 bits on the Assign RHS, but Assign RHS.s CONST '6'h2e' generates 6 bits.
 %Error: Exiting due to},
-	 ) if $Self->{v3};
+    ) if $Self->{vlt};
 
 ok(1);
 1;
diff --git a/test_regress/t/t_flag_wfatal.pl b/test_regress/t/t_flag_wfatal.pl
index 32b8835b8..62c21941c 100755
--- a/test_regress/t/t_flag_wfatal.pl
+++ b/test_regress/t/t_flag_wfatal.pl
@@ -7,17 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt => 1);
+
 top_filename("t/t_flag_wfatal.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
+compile(
     v_flags2 => ["--lint-only -Wno-fatal"],
-    fails=>0,
+    fails => 0,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 q{%Warning-WIDTH: t/t_flag_wfatal.v:\d+: Operator ASSIGNW expects 4 bits on the Assign RHS, but Assign RHS.s CONST '6'h2e' generates 6 bits.
 %Warning-WIDTH: Use .* and lint_on around source to disable this message.
 },
diff --git a/test_regress/t/t_flag_woff.pl b/test_regress/t/t_flag_woff.pl
index ad3f44ee8..7bbcf0f32 100755
--- a/test_regress/t/t_flag_woff.pl
+++ b/test_regress/t/t_flag_woff.pl
@@ -7,9 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only -Wno-WIDTH"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_flag_xinitial_0.pl b/test_regress/t/t_flag_xinitial_0.pl
index e0717a7af..ea707b500 100755
--- a/test_regress/t/t_flag_xinitial_0.pl
+++ b/test_regress/t/t_flag_xinitial_0.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(vlt_all => 1);
+
+compile(
     verilator_flags2 => ["--x-initial 0"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 file_grep_not ("$Self->{obj_dir}/$Self->{VM_PREFIX}.cpp", qr/VL_RAND_RESET/);
diff --git a/test_regress/t/t_flag_xinitial_unique.pl b/test_regress/t/t_flag_xinitial_unique.pl
index 1183667b0..5af7cb2e3 100755
--- a/test_regress/t/t_flag_xinitial_unique.pl
+++ b/test_regress/t/t_flag_xinitial_unique.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(vlt_all => 1);
+
+compile(
     verilator_flags2 => ["--x-initial unique"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 file_grep ("$Self->{obj_dir}/$Self->{VM_PREFIX}.cpp", qr/VL_RAND_RESET/);
diff --git a/test_regress/t/t_for_break.pl b/test_regress/t/t_for_break.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_for_break.pl
+++ b/test_regress/t/t_for_break.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_for_count.pl b/test_regress/t/t_for_count.pl
index 29bf04d49..b1acebe26 100755
--- a/test_regress/t/t_for_count.pl
+++ b/test_regress/t/t_for_count.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_for_funcbound.pl b/test_regress/t/t_for_funcbound.pl
index 605031e04..808880367 100755
--- a/test_regress/t/t_for_funcbound.pl
+++ b/test_regress/t/t_for_funcbound.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 expect=>
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    expect =>
 '[10] hello
 [20] world
 ',
diff --git a/test_regress/t/t_for_init_bug.pl b/test_regress/t/t_for_init_bug.pl
index abf04bf42..47d4dd0ff 100755
--- a/test_regress/t/t_for_init_bug.pl
+++ b/test_regress/t/t_for_init_bug.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-#execute ()
+compile(
+    );
+
+#execute()
 
 ok(1);
 1;
diff --git a/test_regress/t/t_for_local.pl b/test_regress/t/t_for_local.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_for_local.pl
+++ b/test_regress/t/t_for_local.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_for_loop.pl b/test_regress/t/t_for_loop.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_for_loop.pl
+++ b/test_regress/t/t_for_loop.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_foreach.pl b/test_regress/t/t_foreach.pl
index 6b3172aee..676fb4191 100755
--- a/test_regress/t/t_foreach.pl
+++ b/test_regress/t/t_foreach.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--assert']
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 # We expect all loops should be unrolled by verilator,
diff --git a/test_regress/t/t_func.pl b/test_regress/t/t_func.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func.pl
+++ b/test_regress/t/t_func.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_bad.pl b/test_regress/t/t_func_bad.pl
index a5650262e..7d8f21362 100755
--- a/test_regress/t/t_func_bad.pl
+++ b/test_regress/t/t_func_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Error: t/t_func_bad.v:\d+: Missing argument on non-defaulted argument 'from2' in function call to FUNC 'add'
 %Error: t/t_func_bad.v:\d+: Too many arguments in function call to FUNC 'add'
 %Error: t/t_func_bad.v:\d+: Missing argument on non-defaulted argument 'y' in function call to TASK 'x'
@@ -19,7 +21,7 @@ q{%Error: t/t_func_bad.v:\d+: Missing argument on non-defaulted argument 'from2'
 %Error: t/t_func_bad.v:\d+: Duplicate argument 'dup' in function call to FUNC 'f'
 %Error: t/t_func_bad.v:\d+: Too many arguments in function call to FUNC 'f'
 %Error: Exiting due to},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_bad2.pl b/test_regress/t/t_func_bad2.pl
index 69f33cd91..d14343d8d 100755
--- a/test_regress/t/t_func_bad2.pl
+++ b/test_regress/t/t_func_bad2.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_func_bad2.v:\d+: Unsupported: Recursive function or task call
 %Error: Exiting due to',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_bad_width.pl b/test_regress/t/t_func_bad_width.pl
index 9689e4165..499ff7a4e 100755
--- a/test_regress/t/t_func_bad_width.pl
+++ b/test_regress/t/t_func_bad_width.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 q{%Warning-WIDTH: t/t_func_bad_width.v:\d+: Operator FUNCREF 'MUX' expects 40 bits on the Function Argument, but Function Argument's VARREF 'in' generates 39 bits.
 %Warning-WIDTH: Use [^\n]+
 %Warning-WIDTH: t/t_func_bad_width.v:\d+: Operator ASSIGN expects 4 bits on the Assign RHS, but Assign RHS.s FUNCREF 'MUX' generates 32 bits.
 %Error: Exiting due to},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_begin2.pl b/test_regress/t/t_func_begin2.pl
index 08fffbff9..acfde8d55 100755
--- a/test_regress/t/t_func_begin2.pl
+++ b/test_regress/t/t_func_begin2.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only --inline-mult 1"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_check.pl b/test_regress/t/t_func_check.pl
index 27400b3f9..06f37f010 100755
--- a/test_regress/t/t_func_check.pl
+++ b/test_regress/t/t_func_check.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 $Self->{verilated_randReset} = 1;
 
-compile (
-	 );
+compile(
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_const.pl b/test_regress/t/t_func_const.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_const.pl
+++ b/test_regress/t/t_func_const.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_const2_bad.pl b/test_regress/t/t_func_const2_bad.pl
index a3319eb7b..83548112c 100755
--- a/test_regress/t/t_func_const2_bad.pl
+++ b/test_regress/t/t_func_const2_bad.pl
@@ -6,11 +6,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
-#
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Warning-USERFATAL: f_add = 15
 %Warning-USERFATAL: Use "/* verilator lint_off USERFATAL */" and lint_on around source to disable this message.
 %Error: t/t_func_const2_bad.v:10: Expecting expression to be constant, but can't determine constant for FUNCREF 'f_add2'
@@ -25,7 +27,7 @@ t/t_func_const2_bad.v:10:  f_add2() with parameters:
     b = ?32?sh8
     c = ?32?sh9
 },
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_const_bad.pl b/test_regress/t/t_func_const_bad.pl
index 90b9b276d..ac440c192 100755
--- a/test_regress/t/t_func_const_bad.pl
+++ b/test_regress/t/t_func_const_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Error: t/t_func_const_bad.v:11: Expecting expression to be constant, but can't determine constant for FUNCREF 'f_bad_output'
 %Error: t/t_func_const_bad.v:12: ... Location of non-constant VAR 'o': Language violation: Outputs not allowed in constant functions
 %Error: t/t_func_const_bad.v:20: Expecting expression to be constant, but can't determine constant for FUNCREF 'f_bad_dotted'
@@ -44,7 +46,7 @@ Called from:
 t/t_func_const_bad.v:49:  f_bad_fatal() with parameters:
     a = ?32?sh3
 },
-	 );
+     );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_const_packed_array_bad.pl b/test_regress/t/t_func_const_packed_array_bad.pl
index 7620c90f2..1c4925e5a 100755
--- a/test_regress/t/t_func_const_packed_array_bad.pl
+++ b/test_regress/t/t_func_const_packed_array_bad.pl
@@ -6,11 +6,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
-#
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Warning-USERFATAL: f_add = 15
 %Warning-USERFATAL: Use "/* verilator lint_off USERFATAL */" and lint_on around source to disable this message.
 %Error: t/t_func_const_packed_array_bad.v:11: Expecting expression to be constant, but can't determine constant for FUNCREF 'f_add2'
@@ -24,7 +26,7 @@ t/t_func_const_packed_array_bad.v:11:  f_add2() with parameters:
     b = ?32?sh8
     c = ?32?sh9
 },
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_const_packed_struct_bad.pl b/test_regress/t/t_func_const_packed_struct_bad.pl
index dc9b98867..b07a16aa8 100755
--- a/test_regress/t/t_func_const_packed_struct_bad.pl
+++ b/test_regress/t/t_func_const_packed_struct_bad.pl
@@ -6,11 +6,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
-#
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Warning-USERFATAL: f_add = 15
 %Warning-USERFATAL: Use "/* verilator lint_off USERFATAL */" and lint_on around source to disable this message.
 %Error: t/t_func_const_packed_struct_bad.v:13: Expecting expression to be constant, but can't determine constant for FUNCREF 'f_add2'
@@ -24,7 +26,7 @@ t/t_func_const_packed_struct_bad.v:13:  f_add2() with parameters:
     b = ?32?sh8
     c = ?32?sh9
 },
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_const_packed_struct_bad2.pl b/test_regress/t/t_func_const_packed_struct_bad2.pl
index 99d9651d8..d61e7daeb 100755
--- a/test_regress/t/t_func_const_packed_struct_bad2.pl
+++ b/test_regress/t/t_func_const_packed_struct_bad2.pl
@@ -6,11 +6,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
-#
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Warning-USERFATAL: f_add = 15
 %Warning-USERFATAL: Use "/* verilator lint_off USERFATAL */" and lint_on around source to disable this message.
 %Error: t/t_func_const_packed_struct_bad2.v:19: Expecting expression to be constant, but can't determine constant for FUNCREF 'f_add2'
@@ -24,7 +26,7 @@ t/t_func_const_packed_struct_bad2.v:19:  f_add2() with parameters:
     b = ?32?sh8
     c = ?32?sh9
 },
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_const_struct_bad.pl b/test_regress/t/t_func_const_struct_bad.pl
index f19d1e1ef..5395c257e 100755
--- a/test_regress/t/t_func_const_struct_bad.pl
+++ b/test_regress/t/t_func_const_struct_bad.pl
@@ -6,11 +6,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
-#
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Warning-USERFATAL: f_add = 15
 %Warning-USERFATAL: Use "/* verilator lint_off USERFATAL */" and lint_on around source to disable this message.
 %Error: t/t_func_const_struct_bad.v:16: Expecting expression to be constant, but can't determine constant for FUNCREF 'f_add2'
@@ -24,7 +26,7 @@ t/t_func_const_struct_bad.v:16:  f_add2() with parameters:
     b = ?32?sh8
     c = ?32?sh9
 },
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_crc.pl b/test_regress/t/t_func_crc.pl
index dccd4cf50..803dca735 100755
--- a/test_regress/t/t_func_crc.pl
+++ b/test_regress/t/t_func_crc.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ["--compiler msvc"],  # We have deep expressions we want to test
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ["--compiler msvc"],  # We have deep expressions we want to test
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_default_warn.pl b/test_regress/t/t_func_default_warn.pl
index 04736eb19..5f07268a6 100755
--- a/test_regress/t/t_func_default_warn.pl
+++ b/test_regress/t/t_func_default_warn.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["-Wno-WIDTH"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_func_defaults.pl b/test_regress/t/t_func_defaults.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_func_defaults.pl
+++ b/test_regress/t/t_func_defaults.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_func_dotted_inl0.pl b/test_regress/t/t_func_dotted_inl0.pl
index 416707fb9..af2faf33f 100755
--- a/test_regress/t/t_func_dotted_inl0.pl
+++ b/test_regress/t/t_func_dotted_inl0.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_func_dotted.v");
 
-compile (
-	 v_flags2 => ['+define+NOUSE_INLINE',],
-	 );
+compile(
+    v_flags2 => ['+define+NOUSE_INLINE',],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_dotted_inl1.pl b/test_regress/t/t_func_dotted_inl1.pl
index 243dfe84b..0f9ea98bd 100755
--- a/test_regress/t/t_func_dotted_inl1.pl
+++ b/test_regress/t/t_func_dotted_inl1.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_func_dotted.v");
 
-compile (
-	 v_flags2 => ['+define+USE_INLINE',],
-	 );
+compile(
+    v_flags2 => ['+define+USE_INLINE',],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_dotted_inl2.pl b/test_regress/t/t_func_dotted_inl2.pl
index 8e2852494..fc71dbbca 100755
--- a/test_regress/t/t_func_dotted_inl2.pl
+++ b/test_regress/t/t_func_dotted_inl2.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_func_dotted.v");
 
-compile (
-	 v_flags2 => ['+define+USE_INLINE_MID',],
-	 );
+compile(
+    v_flags2 => ['+define+USE_INLINE_MID',],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_endian.pl b/test_regress/t/t_func_endian.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_endian.pl
+++ b/test_regress/t/t_func_endian.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_endian.v b/test_regress/t/t_func_endian.v
index 5df5ca198..1fe1d3fa8 100644
--- a/test_regress/t/t_func_endian.v
+++ b/test_regress/t/t_func_endian.v
@@ -21,13 +21,11 @@ module t (/*AUTOARG*/
    /*AUTOWIRE*/
    // Beginning of automatic wires (for undeclared instantiated-module outputs)
    wire [31:0] 		out;			// From test of Test.v
-   wire [31:0] 		swapped;		// From test of Test.v
    // End of automatics
 
    Test test (/*AUTOINST*/
 	      // Outputs
 	      .out			(out[31:0]),
-	      .swapped			(swapped[31:0]),
 	      // Inputs
 	      .clk			(clk),
 	      .noswap			(noswap),
@@ -67,7 +65,7 @@ endmodule
 
 module Test (/*AUTOARG*/
    // Outputs
-   out, swapped,
+   out,
    // Inputs
    clk, noswap, nibble, in
    );
@@ -78,7 +76,6 @@ module Test (/*AUTOARG*/
 
    input  [31:0] in;
    output [31:0] out;
-   output [31:0] swapped;
 
    function [7:0] EndianSwap;
       input Nibble;
@@ -98,12 +95,4 @@ module Test (/*AUTOARG*/
 			: EndianSwap(nibble, in[15:8]));
    assign out[7:0]   = (noswap ? in[7:0]
 			: EndianSwap(nibble, in[7:0]));
-
-   reg [31:0] swapped;
-   always @(posedge clk) begin
-      swapped[31:24] <= EndianSwap(nibble, in[31:24]);
-      swapped[23:16] <= EndianSwap(nibble, in[23:16]);
-      swapped[15:8]  <= EndianSwap(nibble, in[15:8] );
-      swapped[7:0]   <= EndianSwap(nibble, in[7:0]  );
-   end
 endmodule
diff --git a/test_regress/t/t_func_first.pl b/test_regress/t/t_func_first.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_first.pl
+++ b/test_regress/t/t_func_first.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_flip.pl b/test_regress/t/t_func_flip.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_flip.pl
+++ b/test_regress/t/t_func_flip.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_gen.pl b/test_regress/t/t_func_gen.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_gen.pl
+++ b/test_regress/t/t_func_gen.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_graphcirc.pl b/test_regress/t/t_func_graphcirc.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_graphcirc.pl
+++ b/test_regress/t/t_func_graphcirc.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_grey.pl b/test_regress/t/t_func_grey.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_grey.pl
+++ b/test_regress/t/t_func_grey.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_lib.pl b/test_regress/t/t_func_lib.pl
index e0169b77e..e002e1c21 100755
--- a/test_regress/t/t_func_lib.pl
+++ b/test_regress/t/t_func_lib.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ['-v', 't/t_func_lib_sub.v'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    v_flags2 => ['-v', 't/t_func_lib_sub.v'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_lib_sub.pl b/test_regress/t/t_func_lib_sub.pl
index 79580b4a7..95facfefc 100755
--- a/test_regress/t/t_func_lib_sub.pl
+++ b/test_regress/t/t_func_lib_sub.pl
@@ -7,10 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 );
+compile(
+    );
 # No execute
 ok(1);
 1;
diff --git a/test_regress/t/t_func_mlog2.pl b/test_regress/t/t_func_mlog2.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_mlog2.pl
+++ b/test_regress/t/t_func_mlog2.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_named.pl b/test_regress/t/t_func_named.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_func_named.pl
+++ b/test_regress/t/t_func_named.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_func_noinl.pl b/test_regress/t/t_func_noinl.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_noinl.pl
+++ b/test_regress/t/t_func_noinl.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_numones.pl b/test_regress/t/t_func_numones.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_numones.pl
+++ b/test_regress/t/t_func_numones.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_outfirst.pl b/test_regress/t/t_func_outfirst.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_outfirst.pl
+++ b/test_regress/t/t_func_outfirst.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_outp.pl b/test_regress/t/t_func_outp.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_outp.pl
+++ b/test_regress/t/t_func_outp.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_paramed.pl b/test_regress/t/t_func_paramed.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_paramed.pl
+++ b/test_regress/t/t_func_paramed.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_plog.pl b/test_regress/t/t_func_plog.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_plog.pl
+++ b/test_regress/t/t_func_plog.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_public.pl b/test_regress/t/t_func_public.pl
index bd8fd8c45..a29ba45ad 100755
--- a/test_regress/t/t_func_public.pl
+++ b/test_regress/t/t_func_public.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ['+define+VERILATOR_PUBLIC_TASKS'],
-	 fails => $fail,
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    verilator_flags2 => ['+define+VERILATOR_PUBLIC_TASKS'],
+    fails => $fail,
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_public_trace.pl b/test_regress/t/t_func_public_trace.pl
index bc1d49232..74b4c78ea 100755
--- a/test_regress/t/t_func_public_trace.pl
+++ b/test_regress/t/t_func_public_trace.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-my $pubtask = ($Self->{v3} && verilator_version() =~ /\(public_tasks\)/);  # TBD
+scenarios(simulator => 1);
+
+my $pubtask = ($Self->{vlt} && verilator_version() =~ /\(public_tasks\)/);  # TBD
 
 top_filename("t/t_func_public.v");
 
-compile (
-	 verilator_flags2 => [($pubtask?'-DVERILATOR_PUBLIC_TASKS':''), "--trace"],
-	 fails => $fail,
-	 );
+compile(
+    verilator_flags2 => [($pubtask?'-DVERILATOR_PUBLIC_TASKS':''), "--trace"],
+    fails => $fail,
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_rand.pl b/test_regress/t/t_func_rand.pl
index db8cb35f9..6c781245e 100755
--- a/test_regress/t/t_func_rand.pl
+++ b/test_regress/t/t_func_rand.pl
@@ -7,17 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
-	 );
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_range.pl b/test_regress/t/t_func_range.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_range.pl
+++ b/test_regress/t/t_func_range.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_real_abs.pl b/test_regress/t/t_func_real_abs.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_func_real_abs.pl
+++ b/test_regress/t/t_func_real_abs.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_func_real_param.pl b/test_regress/t/t_func_real_param.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_real_param.pl
+++ b/test_regress/t/t_func_real_param.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_regfirst.pl b/test_regress/t/t_func_regfirst.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_regfirst.pl
+++ b/test_regress/t/t_func_regfirst.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_return.pl b/test_regress/t/t_func_return.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_return.pl
+++ b/test_regress/t/t_func_return.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_sum.pl b/test_regress/t/t_func_sum.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_sum.pl
+++ b/test_regress/t/t_func_sum.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_task_bad.pl b/test_regress/t/t_func_task_bad.pl
index cb13de9e8..0c15dee26 100755
--- a/test_regress/t/t_func_task_bad.pl
+++ b/test_regress/t/t_func_task_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Error: t/t_func_task_bad.v:\d+: Illegal call of a task as a function: task_as_func
 %Error: Exiting due to.*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_tie_bad.pl b/test_regress/t/t_func_tie_bad.pl
index 23ee4055b..46d459dcb 100755
--- a/test_regress/t/t_func_tie_bad.pl
+++ b/test_regress/t/t_func_tie_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Error: t/t_func_tie_bad.v:\d+: Function/task output connected to constant instead of variable: b
 %Error: Exiting due to.*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_twocall.pl b/test_regress/t/t_func_twocall.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_twocall.pl
+++ b/test_regress/t/t_func_twocall.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_types.pl b/test_regress/t/t_func_types.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_types.pl
+++ b/test_regress/t/t_func_types.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_under.pl b/test_regress/t/t_func_under.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_func_under.pl
+++ b/test_regress/t/t_func_under.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_func_under2.pl b/test_regress/t/t_func_under2.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_func_under2.pl
+++ b/test_regress/t/t_func_under2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_func_v.pl b/test_regress/t/t_func_v.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_func_v.pl
+++ b/test_regress/t/t_func_v.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_func_v_noinl.pl b/test_regress/t/t_func_v_noinl.pl
index e271e1195..fd294abcb 100755
--- a/test_regress/t/t_func_v_noinl.pl
+++ b/test_regress/t/t_func_v_noinl.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_func_v.v");
 
-compile (
+compile(
     v_flags2 => ['+define+T_FUNC_V_NOINL',],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_func_wide.pl b/test_regress/t/t_func_wide.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_func_wide.pl
+++ b/test_regress/t/t_func_wide.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_func_wide_out_bad.pl b/test_regress/t/t_func_wide_out_bad.pl
index 195a6f8d8..ec42e1260 100755
--- a/test_regress/t/t_func_wide_out_bad.pl
+++ b/test_regress/t/t_func_wide_out_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Error: t/t_func_wide_out_bad.v:\d+: Unsupported: Function output argument 'data' requires 4352 bits, but connection's VARREF 'msg' generates 4350 bits.
 %Error: Exiting due to.*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gate_array.pl b/test_regress/t/t_gate_array.pl
index 30da50378..b1acebe26 100755
--- a/test_regress/t/t_gate_array.pl
+++ b/test_regress/t/t_gate_array.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_gate_basic.pl b/test_regress/t/t_gate_basic.pl
index 29bf04d49..b1acebe26 100755
--- a/test_regress/t/t_gate_basic.pl
+++ b/test_regress/t/t_gate_basic.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gate_chained.pl b/test_regress/t/t_gate_chained.pl
index 4c6b9aeae..f77d4afd1 100755
--- a/test_regress/t/t_gate_chained.pl
+++ b/test_regress/t/t_gate_chained.pl
@@ -8,6 +8,8 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Version 2.0.
 use IO::File;
 
+scenarios(simulator => 1);
+
 sub gen {
     my $filename = shift;
 
@@ -41,12 +43,12 @@ top_filename("$Self->{obj_dir}/t_gate_chained.v");
 
 gen($Self->{top_filename});
 
-compile (
+compile(
     verilator_flags2=>["--stats --x-assign fast --x-initial fast"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 # Must be <<9000 above to prove this worked
diff --git a/test_regress/t/t_gate_elim.pl b/test_regress/t/t_gate_elim.pl
index 29bf04d49..b1acebe26 100755
--- a/test_regress/t/t_gate_elim.pl
+++ b/test_regress/t/t_gate_elim.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gate_implicit.pl b/test_regress/t/t_gate_implicit.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gate_implicit.pl
+++ b/test_regress/t/t_gate_implicit.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gate_unsup.pl b/test_regress/t/t_gate_unsup.pl
index cf12070f2..a45d22739 100755
--- a/test_regress/t/t_gate_unsup.pl
+++ b/test_regress/t/t_gate_unsup.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     # Unsupported: UDP Tables
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_gated_clk_1.pl b/test_regress/t/t_gated_clk_1.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_gated_clk_1.pl
+++ b/test_regress/t/t_gated_clk_1.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_gen_alw.pl b/test_regress/t/t_gen_alw.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_alw.pl
+++ b/test_regress/t/t_gen_alw.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_assign.pl b/test_regress/t/t_gen_assign.pl
index d39b6f866..45e24b34a 100755
--- a/test_regress/t/t_gen_assign.pl
+++ b/test_regress/t/t_gen_assign.pl
@@ -7,10 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 );
+compile(
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_cond_bitrange.pl b/test_regress/t/t_gen_cond_bitrange.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_cond_bitrange.pl
+++ b/test_regress/t/t_gen_cond_bitrange.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_cond_bitrange_bad.pl b/test_regress/t/t_gen_cond_bitrange_bad.pl
index 704fafa6a..3cec319f2 100755
--- a/test_regress/t/t_gen_cond_bitrange_bad.pl
+++ b/test_regress/t/t_gen_cond_bitrange_bad.pl
@@ -7,17 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Warning-SELRANGE: t/t_gen_cond_bitrange_bad.v:\d+: Selection index out of range: 2:2 outside 1:0
 %Warning-SELRANGE: Use .*
 %Warning-SELRANGE: t/t_gen_cond_bitrange_bad.v:\d+: Selection index out of range: 2:2 outside 1:0
 %Warning-SELRANGE: t/t_gen_cond_bitrange_bad.v:\d+: Selection index out of range: 2:2 outside 1:0
 %Warning-SELRANGE: t/t_gen_cond_bitrange_bad.v:\d+: Selection index out of range: 2:2 outside 1:0
 %Error: Exiting due to .*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_cond_const.pl b/test_regress/t/t_gen_cond_const.pl
index 304357b8c..549d3c8f8 100755
--- a/test_regress/t/t_gen_cond_const.pl
+++ b/test_regress/t/t_gen_cond_const.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    verilator_flags2 => ["--language 1364-2001"]
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ["--language 1364-2001"]
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_defparam.pl b/test_regress/t/t_gen_defparam.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_defparam.pl
+++ b/test_regress/t/t_gen_defparam.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_div0.pl b/test_regress/t/t_gen_div0.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_div0.pl
+++ b/test_regress/t/t_gen_div0.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_for.pl b/test_regress/t/t_gen_for.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_for.pl
+++ b/test_regress/t/t_gen_for.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_for0.pl b/test_regress/t/t_gen_for0.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_for0.pl
+++ b/test_regress/t/t_gen_for0.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_for1.pl b/test_regress/t/t_gen_for1.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_for1.pl
+++ b/test_regress/t/t_gen_for1.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_for2.pl b/test_regress/t/t_gen_for2.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_gen_for2.pl
+++ b/test_regress/t/t_gen_for2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_gen_for_overlap.pl b/test_regress/t/t_gen_for_overlap.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_gen_for_overlap.pl
+++ b/test_regress/t/t_gen_for_overlap.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_gen_for_shuffle.pl b/test_regress/t/t_gen_for_shuffle.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_for_shuffle.pl
+++ b/test_regress/t/t_gen_for_shuffle.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_forif.pl b/test_regress/t/t_gen_forif.pl
index 715674488..26ef67a0b 100755
--- a/test_regress/t/t_gen_forif.pl
+++ b/test_regress/t/t_gen_forif.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 nc_flags2 => ['+access+r'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    nc_flags2 => ['+access+r'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_if.pl b/test_regress/t/t_gen_if.pl
index 259d5b775..33ff6d6c0 100755
--- a/test_regress/t/t_gen_if.pl
+++ b/test_regress/t/t_gen_if.pl
@@ -7,10 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 );
+compile(
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_inc.pl b/test_regress/t/t_gen_inc.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_inc.pl
+++ b/test_regress/t/t_gen_inc.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_index.pl b/test_regress/t/t_gen_index.pl
index 8e68549ed..b9cf6967c 100755
--- a/test_regress/t/t_gen_index.pl
+++ b/test_regress/t/t_gen_index.pl
@@ -7,8 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # Compile time only test
-compile (
+compile(
     );
 
 ok(1);
diff --git a/test_regress/t/t_gen_intdot.pl b/test_regress/t/t_gen_intdot.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_intdot.pl
+++ b/test_regress/t/t_gen_intdot.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_intdot.v b/test_regress/t/t_gen_intdot.v
index 54c18423d..fe457f57d 100644
--- a/test_regress/t/t_gen_intdot.v
+++ b/test_regress/t/t_gen_intdot.v
@@ -3,6 +3,8 @@
 // This file ONLY is placed into the Public Domain, for any use,
 // without warranty, 2003-2007 by Wilson Snyder.
 
+`define STRINGIFY(x) `"x`"
+
 module t (/*AUTOARG*/
    // Inputs
    clk
@@ -40,7 +42,7 @@ module t (/*AUTOARG*/
 //`define WAVES
 `ifdef WAVES
    initial begin
-      $dumpfile("obj_dir/t_gen_intdot/t_gen_intdot.vcd");
+      $dumpfile({`STRINGIFY(`TEST_OBJ_DIR),"/simx.vcd"});
       $dumpvars(12, t);
    end
 `endif
diff --git a/test_regress/t/t_gen_intdot2.pl b/test_regress/t/t_gen_intdot2.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_intdot2.pl
+++ b/test_regress/t/t_gen_intdot2.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_intdot2.v b/test_regress/t/t_gen_intdot2.v
index f0212e91a..75a4d51ab 100644
--- a/test_regress/t/t_gen_intdot2.v
+++ b/test_regress/t/t_gen_intdot2.v
@@ -3,6 +3,8 @@
 // This file ONLY is placed into the Public Domain, for any use,
 // without warranty, 2003-2007 by Wilson Snyder.
 
+`define STRINGIFY(x) `"x`"
+
 module t (/*AUTOARG*/
    // Inputs
    clk
@@ -33,7 +35,7 @@ module t (/*AUTOARG*/
 //`define WAVES
 `ifdef WAVES
    initial begin
-      $dumpfile("obj_dir/t_gen_intdot2/t_gen_intdot.vcd");
+      $dumpfile({`STRINGIFY(`TEST_OBJ_DIR),"/simx.vcd"});
       $dumpvars(12, t);
    end
 `endif
diff --git a/test_regress/t/t_gen_local.pl b/test_regress/t/t_gen_local.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_local.pl
+++ b/test_regress/t/t_gen_local.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_lsb.pl b/test_regress/t/t_gen_lsb.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_gen_lsb.pl
+++ b/test_regress/t/t_gen_lsb.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_gen_mislevel.pl b/test_regress/t/t_gen_mislevel.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_gen_mislevel.pl
+++ b/test_regress/t/t_gen_mislevel.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_missing.pl b/test_regress/t/t_gen_missing.pl
index bfdf34e07..5582e61c4 100755
--- a/test_regress/t/t_gen_missing.pl
+++ b/test_regress/t/t_gen_missing.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ['+define+T_GEN_MISSING'],
     );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_gen_missing_bad.pl b/test_regress/t/t_gen_missing_bad.pl
index 7710a9ab5..407bc7eb2 100755
--- a/test_regress/t/t_gen_missing_bad.pl
+++ b/test_regress/t/t_gen_missing_bad.pl
@@ -7,13 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt => 1);
+
 top_filename("t/t_gen_missing.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-compile (
+compile(
     v_flags2 => ['+define+T_GEN_MISSING_BAD'],
     fails => 1,
-    expect=>
+    expect =>
 '%Error: t/t_gen_missing.v:\d+: Cannot find file containing module: foo_not_needed
 %Error: t/t_gen_missing.v:\d+: Looked in:
 %Error: t/t_gen_missing.v:\d+:       t/foo_not_needed
diff --git a/test_regress/t/t_gen_upscope.pl b/test_regress/t/t_gen_upscope.pl
index 1d26eb10b..7b502e256 100755
--- a/test_regress/t/t_gen_upscope.pl
+++ b/test_regress/t/t_gen_upscope.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
-	 expect=>quotemeta(
+execute(
+    check_finished => 1,
+    expect => quotemeta(
 q{created tag with scope = top.t.b.gen[0].tag
 created tag with scope = top.t.b.gen[1].tag
 created tag with scope = top.t.tag
diff --git a/test_regress/t/t_gen_var_bad.pl b/test_regress/t/t_gen_var_bad.pl
index c7ce268c2..c4230c3cf 100755
--- a/test_regress/t/t_gen_var_bad.pl
+++ b/test_regress/t/t_gen_var_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '.*%Error: t/t_gen_var_bad.v:\d+: Non-genvar used in generate for: i
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_genfor_hier.pl b/test_regress/t/t_genfor_hier.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_genfor_hier.pl
+++ b/test_regress/t/t_genfor_hier.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_genvar_misuse_bad.pl b/test_regress/t/t_genvar_misuse_bad.pl
index 38624e801..4bac96d95 100755
--- a/test_regress/t/t_genvar_misuse_bad.pl
+++ b/test_regress/t/t_genvar_misuse_bad.pl
@@ -7,15 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, bug408");
+scenarios(simulator => 1);
+$Self->{vlt} and unsupported("Verilator unsupported, bug408");
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '.*%Error: t/t_genvar_misuse_bad.v:\d+: Use of genvar where not convertible to constant: i
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_help.pl b/test_regress/t/t_help.pl
index a69698231..057320634 100755
--- a/test_regress/t/t_help.pl
+++ b/test_regress/t/t_help.pl
@@ -7,7 +7,7 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(dist => 1);
 
 foreach my $prog (
     "../bin/verilator",
@@ -15,11 +15,11 @@ foreach my $prog (
     "../bin/verilator_difftree",
     "../bin/verilator_profcfunc",
     ) {
-    $Self->run(fails=>1,
-               cmd=>["perl",$prog,
-                     "--help"],
-               logfile=>"$Self->{obj_dir}/t_help.log",
-               tee=>0,
+    run(fails => 1,
+        cmd => ["perl",$prog,
+                "--help"],
+        logfile => "$Self->{obj_dir}/t_help.log",
+        tee => 0,
         );
     file_grep ("$Self->{obj_dir}/t_help.log", qr/DISTRIBUTION/i);
 }
diff --git a/test_regress/t/t_hierarchy_identifier.pl b/test_regress/t/t_hierarchy_identifier.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_hierarchy_identifier.pl
+++ b/test_regress/t/t_hierarchy_identifier.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_hierarchy_identifier_bad.pl b/test_regress/t/t_hierarchy_identifier_bad.pl
index 45c69b502..5f1ed88d5 100755
--- a/test_regress/t/t_hierarchy_identifier_bad.pl
+++ b/test_regress/t/t_hierarchy_identifier_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Warning-ENDLABEL: t/t_hierarchy_identifier_bad.v:\d+: End label 'if_cnt_finish_bad' does not match begin label 'if_cnt_finish'
 %Warning-ENDLABEL: Use .*
 %Warning-ENDLABEL: t/t_hierarchy_identifier_bad.v:\d+: End label 'generate_for_bad' does not match begin label 'generate_for'
diff --git a/test_regress/t/t_hierarchy_unnamed.pl b/test_regress/t/t_hierarchy_unnamed.pl
index 514f638f2..dd4decbdb 100755
--- a/test_regress/t/t_hierarchy_unnamed.pl
+++ b/test_regress/t/t_hierarchy_unnamed.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_if_deep.pl b/test_regress/t/t_if_deep.pl
index dccd4cf50..803dca735 100755
--- a/test_regress/t/t_if_deep.pl
+++ b/test_regress/t/t_if_deep.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ["--compiler msvc"],  # We have deep expressions we want to test
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ["--compiler msvc"],  # We have deep expressions we want to test
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_init_concat.pl b/test_regress/t/t_init_concat.pl
index 29bf04d49..b1acebe26 100755
--- a/test_regress/t/t_init_concat.pl
+++ b/test_regress/t/t_init_concat.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_initarray_nonarray.pl b/test_regress/t/t_initarray_nonarray.pl
index 385b6a57e..5c448de7c 100755
--- a/test_regress/t/t_initarray_nonarray.pl
+++ b/test_regress/t/t_initarray_nonarray.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
 ok(1);
diff --git a/test_regress/t/t_initial.pl b/test_regress/t/t_initial.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_initial.pl
+++ b/test_regress/t/t_initial.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_initial_dlyass.pl b/test_regress/t/t_initial_dlyass.pl
index fc8d21fa6..8b4eb7d5d 100755
--- a/test_regress/t/t_initial_dlyass.pl
+++ b/test_regress/t/t_initial_dlyass.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['-Wno-INITIALDLY'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_initial_dlyass_bad.pl b/test_regress/t/t_initial_dlyass_bad.pl
index b0af1d491..ab06709d5 100755
--- a/test_regress/t/t_initial_dlyass_bad.pl
+++ b/test_regress/t/t_initial_dlyass_bad.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t_initial_dlyass.v");
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 qr{%Warning-INITIALDLY: t/t_initial_dlyass.v:\d+: Delayed assignments .*
 %Error: Exiting due to.*},
      );
diff --git a/test_regress/t/t_initial_edge.pl b/test_regress/t/t_initial_edge.pl
index 8a07c2001..a07391fc7 100755
--- a/test_regress/t/t_initial_edge.pl
+++ b/test_regress/t/t_initial_edge.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--x-initial-edge"]
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_initial_edge_bad.pl b/test_regress/t/t_initial_edge_bad.pl
index f8eccd9c8..3a4a9fa92 100755
--- a/test_regress/t/t_initial_edge_bad.pl
+++ b/test_regress/t/t_initial_edge_bad.pl
@@ -7,16 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+# This works with other vlt_alls, we we don't run it for them. It should
+# fail with Verilator if --x-initial-edge is not specified.
+
+scenarios(vlt_all => 1);
+
 top_filename("t/t_initial_edge.v");
 
-# This works with other simulators, we we don't run it for them. It should
-# fail with Verilator if --x-initial-edge is not specified.
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
+compile(
     );
 
-execute (
+execute(
     fails => 1,
     );
 
diff --git a/test_regress/t/t_inside.pl b/test_regress/t/t_inside.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_inside.pl
+++ b/test_regress/t/t_inside.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inside_wild.pl b/test_regress/t/t_inside_wild.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_inside_wild.pl
+++ b/test_regress/t/t_inside_wild.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_aport.pl b/test_regress/t/t_inst_aport.pl
index e5854cbed..adbfdeea8 100755
--- a/test_regress/t/t_inst_aport.pl
+++ b/test_regress/t/t_inst_aport.pl
@@ -7,13 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->unsupported("Verilator/commercial slice unsupported, bug711");
+scenarios(simulator => 1);
+unsupported("Verilator/commercial slice unsupported, bug711");
 
-compile (
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_array_bad.pl b/test_regress/t/t_inst_array_bad.pl
index 5e134d0ba..dc544d3d6 100755
--- a/test_regress/t/t_inst_array_bad.pl
+++ b/test_regress/t/t_inst_array_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Error: t/t_inst_array_bad.v:\d+: Input port connection 'onebit' as part of a module instance array requires 1 or 8 bits, but connection's VARREF 'onebitbad' generates 9 bits.
 %Error: Exiting due to.*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_array_inl0.pl b/test_regress/t/t_inst_array_inl0.pl
index f03ad145d..c4cccd0b0 100755
--- a/test_regress/t/t_inst_array_inl0.pl
+++ b/test_regress/t/t_inst_array_inl0.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_array.v");
 
-compile (
-	 v_flags2 => ['+define+NOUSE_INLINE',],
-	 );
+compile(
+    v_flags2 => ['+define+NOUSE_INLINE',],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_array_inl1.pl b/test_regress/t/t_inst_array_inl1.pl
index 06725c5c6..497533ec6 100755
--- a/test_regress/t/t_inst_array_inl1.pl
+++ b/test_regress/t/t_inst_array_inl1.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_array.v");
 
-compile (
-	 v_flags2 => ['+define+USE_INLINE',],
-	 );
+compile(
+    v_flags2 => ['+define+USE_INLINE',],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_array_partial.pl b/test_regress/t/t_inst_array_partial.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_inst_array_partial.pl
+++ b/test_regress/t/t_inst_array_partial.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_ccall.pl b/test_regress/t/t_inst_ccall.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_inst_ccall.pl
+++ b/test_regress/t/t_inst_ccall.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_comma_inl0.pl b/test_regress/t/t_inst_comma_inl0.pl
index 1edc160f1..b9b6bc01a 100755
--- a/test_regress/t/t_inst_comma_inl0.pl
+++ b/test_regress/t/t_inst_comma_inl0.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_comma.v");
 
-compile (
-	 v_flags2 => ['+define+NOUSE_INLINE',],
-	 );
+compile(
+    v_flags2 => ['+define+NOUSE_INLINE',],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_comma_inl1.pl b/test_regress/t/t_inst_comma_inl1.pl
index 7f7f4aeda..553b96107 100755
--- a/test_regress/t/t_inst_comma_inl1.pl
+++ b/test_regress/t/t_inst_comma_inl1.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_comma.v");
 
-compile (
-	 v_flags2 => ['+define+USE_INLINE',],
-	 );
+compile(
+    v_flags2 => ['+define+USE_INLINE',],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_darray.pl b/test_regress/t/t_inst_darray.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_inst_darray.pl
+++ b/test_regress/t/t_inst_darray.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_dff.pl b/test_regress/t/t_inst_dff.pl
index 30da50378..b1acebe26 100755
--- a/test_regress/t/t_inst_dff.pl
+++ b/test_regress/t/t_inst_dff.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_dtree_inla.pl b/test_regress/t/t_inst_dtree_inla.pl
index fe688b136..3862d5166 100755
--- a/test_regress/t/t_inst_dtree_inla.pl
+++ b/test_regress/t/t_inst_dtree_inla.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_dtree.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_A'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_dtree_inlab.pl b/test_regress/t/t_inst_dtree_inlab.pl
index 01b6ddf38..a17eec491 100755
--- a/test_regress/t/t_inst_dtree_inlab.pl
+++ b/test_regress/t/t_inst_dtree_inlab.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_dtree.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_A +define+INLINE_B'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_dtree_inlac.pl b/test_regress/t/t_inst_dtree_inlac.pl
index 1125007cf..31f5e113c 100755
--- a/test_regress/t/t_inst_dtree_inlac.pl
+++ b/test_regress/t/t_inst_dtree_inlac.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_dtree.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_A +define+INLINE_C'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_dtree_inlad.pl b/test_regress/t/t_inst_dtree_inlad.pl
index 691fa1822..c9aa2cfec 100755
--- a/test_regress/t/t_inst_dtree_inlad.pl
+++ b/test_regress/t/t_inst_dtree_inlad.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_dtree.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_A +define+INLINE_D'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_dtree_inlb.pl b/test_regress/t/t_inst_dtree_inlb.pl
index 3113b83b1..ddf31e7f3 100755
--- a/test_regress/t/t_inst_dtree_inlb.pl
+++ b/test_regress/t/t_inst_dtree_inlb.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_dtree.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_B'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_dtree_inlbc.pl b/test_regress/t/t_inst_dtree_inlbc.pl
index cb87439b8..f2046ecfb 100755
--- a/test_regress/t/t_inst_dtree_inlbc.pl
+++ b/test_regress/t/t_inst_dtree_inlbc.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_dtree.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_B +define+INLINE_C'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_dtree_inlbd.pl b/test_regress/t/t_inst_dtree_inlbd.pl
index bfffeb2fa..d9a539536 100755
--- a/test_regress/t/t_inst_dtree_inlbd.pl
+++ b/test_regress/t/t_inst_dtree_inlbd.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_dtree.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_B +define+INLINE_D'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_dtree_inlc.pl b/test_regress/t/t_inst_dtree_inlc.pl
index 06ac28071..c36be6cda 100755
--- a/test_regress/t/t_inst_dtree_inlc.pl
+++ b/test_regress/t/t_inst_dtree_inlc.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_dtree.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_C'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_dtree_inlcd.pl b/test_regress/t/t_inst_dtree_inlcd.pl
index 1023f1a43..fcc73c54d 100755
--- a/test_regress/t/t_inst_dtree_inlcd.pl
+++ b/test_regress/t/t_inst_dtree_inlcd.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_dtree.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_C +define+INLINE_D'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_dtree_inld.pl b/test_regress/t/t_inst_dtree_inld.pl
index bfb903e56..5c16b1988 100755
--- a/test_regress/t/t_inst_dtree_inld.pl
+++ b/test_regress/t/t_inst_dtree_inld.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_dtree.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_D'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_first.pl b/test_regress/t/t_inst_first.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_inst_first.pl
+++ b/test_regress/t/t_inst_first.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_implicit.pl b/test_regress/t/t_inst_implicit.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_inst_implicit.pl
+++ b/test_regress/t/t_inst_implicit.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_misarray_bad.pl b/test_regress/t/t_inst_misarray_bad.pl
index aa6e86031..b87a8f781 100755
--- a/test_regress/t/t_inst_misarray_bad.pl
+++ b/test_regress/t/t_inst_misarray_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--lint-only"],
     fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 q{%Error: t/t_inst_misarray_bad.v:16: VARREF 't.foo' is not an unpacked array, but is in an unpacked array context
 %Error: Exiting due to.*},
     );
diff --git a/test_regress/t/t_inst_mism.pl b/test_regress/t/t_inst_mism.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_inst_mism.pl
+++ b/test_regress/t/t_inst_mism.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_missing.pl b/test_regress/t/t_inst_missing.pl
index 42325c365..20cf980fd 100755
--- a/test_regress/t/t_inst_missing.pl
+++ b/test_regress/t/t_inst_missing.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only --Wall -Wno-DECLFILENAME"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_inst_missing_bad.pl b/test_regress/t/t_inst_missing_bad.pl
index 6db6466b5..cac41ce28 100755
--- a/test_regress/t/t_inst_missing_bad.pl
+++ b/test_regress/t/t_inst_missing_bad.pl
@@ -7,16 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only --Wall -Wno-DECLFILENAME"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only --Wall -Wno-DECLFILENAME"],
+    fails => 1,
+    expect =>
 q{%Warning-PINNOCONNECT: t/t_inst_missing_bad.v:8: Cell pin is not connected: __pinNumber2
 %Warning-PINNOCONNECT: Use .*
 %Warning-PINCONNECTEMPTY: t/t_inst_missing_bad.v:8: Cell pin connected by name with empty reference: nc
 %Warning-PINMISSING: t/t_inst_missing_bad.v:8: Cell has missing pin: missing
 %Error: Exiting due to.*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_mnpipe.pl b/test_regress/t/t_inst_mnpipe.pl
index fd76d2220..1be18a66c 100755
--- a/test_regress/t/t_inst_mnpipe.pl
+++ b/test_regress/t/t_inst_mnpipe.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_notunsized.pl b/test_regress/t/t_inst_notunsized.pl
index 0d595fbd7..7654e1a4e 100755
--- a/test_regress/t/t_inst_notunsized.pl
+++ b/test_regress/t/t_inst_notunsized.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    verilator_flags2=>["-Wno-IMPLICIT"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2=>["-Wno-IMPLICIT"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_overwide.pl b/test_regress/t/t_inst_overwide.pl
index 2d0bd83ee..dfea2018b 100755
--- a/test_regress/t/t_inst_overwide.pl
+++ b/test_regress/t/t_inst_overwide.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 make_top_shell=>0,
-	 verilator_flags2 => [qw(-sc -Wno-WIDTH)],
-	 verilator_make_gcc=>0,
-	 );
+scenarios(simulator => 1);
 
-#No execute ()
+compile(
+    make_top_shell => 0,
+    verilator_flags2 => [qw(-sc -Wno-WIDTH)],
+    verilator_make_gcc => 0,
+    );
+
+#No execute()
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_overwide_bad.pl b/test_regress/t/t_inst_overwide_bad.pl
index 6e0b9ae94..89c911e01 100755
--- a/test_regress/t/t_inst_overwide_bad.pl
+++ b/test_regress/t/t_inst_overwide_bad.pl
@@ -7,22 +7,24 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_overwide.v");
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 make_top_shell=>0,
-	 verilator_flags=> [qw(-cc)],
-	 verilator_make_gcc=>0,
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    make_top_shell => 0,
+    verilator_flags => [qw(-cc)],
+    verilator_make_gcc => 0,
+    fails => $Self->{vlt},
+    expect =>
 q{%Warning-WIDTH: t/t_inst_overwide.v:\d+: Output port connection 'outy_w92' expects 92 bits on the pin connection, but pin connection's VARREF 'outc_w30' generates 30 bits.
 %Warning-WIDTH: Use .* to disable this message.
 %Warning-WIDTH: t/t_inst_overwide.v:\d+: Output port connection 'outz_w22' expects 22 bits on the pin connection, but pin connection's VARREF 'outd_w73' generates 73 bits.
 %Warning-WIDTH: t/t_inst_overwide.v:\d+: Input port connection 'inw_w31' expects 31 bits on the pin connection, but pin connection's VARREF 'ina_w1' generates 1 bits.
 %Warning-WIDTH: t/t_inst_overwide.v:\d+: Input port connection 'inx_w11' expects 11 bits on the pin connection, but pin connection's VARREF 'inb_w61' generates 61 bits.
 %Error: Exiting due to.*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_port_array.pl b/test_regress/t/t_inst_port_array.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_inst_port_array.pl
+++ b/test_regress/t/t_inst_port_array.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_prepost.pl b/test_regress/t/t_inst_prepost.pl
index 385b6a57e..5c448de7c 100755
--- a/test_regress/t/t_inst_prepost.pl
+++ b/test_regress/t/t_inst_prepost.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_recurse2_bad.pl b/test_regress/t/t_inst_recurse2_bad.pl
index b6f94e500..95e358ccc 100755
--- a/test_regress/t/t_inst_recurse2_bad.pl
+++ b/test_regress/t/t_inst_recurse2_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    fails=>1,
-    expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 '.*%Error: t/t_inst_recurse2_bad.v:\d+: Unsupported: Identically recursive module \(module instantiates itself, without changing parameters\): looped
 %Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_inst_recurse_bad.pl b/test_regress/t/t_inst_recurse_bad.pl
index cd8941191..e0a1fb933 100755
--- a/test_regress/t/t_inst_recurse_bad.pl
+++ b/test_regress/t/t_inst_recurse_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    fails=>1,
-    expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 '.*%Error: t/t_inst_recurse_bad.v:\d+: Unsupported: Recursive multiple modules \(module instantiates something leading back to itself\): looped
 %Error: t/t_inst_recurse_bad.v:\d+: Note self-recursion \(module instantiating itself directly\) is supported.
 %Error: Exiting due to.*',
diff --git a/test_regress/t/t_inst_signed.pl b/test_regress/t/t_inst_signed.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_inst_signed.pl
+++ b/test_regress/t/t_inst_signed.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_signed1.pl b/test_regress/t/t_inst_signed1.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_inst_signed1.pl
+++ b/test_regress/t/t_inst_signed1.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_slice.pl b/test_regress/t/t_inst_slice.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_inst_slice.pl
+++ b/test_regress/t/t_inst_slice.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_slice_noinl.pl b/test_regress/t/t_inst_slice_noinl.pl
index 56c4c8f6f..d9c0024d1 100755
--- a/test_regress/t/t_inst_slice_noinl.pl
+++ b/test_regress/t/t_inst_slice_noinl.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_slice.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_inst_sv.pl b/test_regress/t/t_inst_sv.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_inst_sv.pl
+++ b/test_regress/t/t_inst_sv.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_tree_inl0_pub0.pl b/test_regress/t/t_inst_tree_inl0_pub0.pl
index cb1704bb1..b9f879e8b 100755
--- a/test_regress/t/t_inst_tree_inl0_pub0.pl
+++ b/test_regress/t/t_inst_tree_inl0_pub0.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_tree.v");
 
-compile (
-	 v_flags2 => ['+define+NOUSE_INLINE', '+define+NOUSE_PUBLIC'],
-	 );
+compile(
+    v_flags2 => ['+define+NOUSE_INLINE', '+define+NOUSE_PUBLIC'],
+    );
 
-execute (
-	 check_finished=>1,
-	 expect=>
+execute(
+    check_finished => 1,
+    expect =>
 '\] (%m|.*t\.ps): Clocked
 ',
-     );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_tree_inl0_pub1.pl b/test_regress/t/t_inst_tree_inl0_pub1.pl
index c5593b090..cd76d7848 100755
--- a/test_regress/t/t_inst_tree_inl0_pub1.pl
+++ b/test_regress/t/t_inst_tree_inl0_pub1.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_tree.v");
 
-compile (
-	 verilator_flags2 => ['+define+NOUSE_INLINE', '+define+USE_PUBLIC', '--stats'],
-	 );
+compile(
+    verilator_flags2 => ['+define+NOUSE_INLINE', '+define+USE_PUBLIC', '--stats'],
+    );
 
 sub checkRelativeRefs {
     my ($mod, $expect_relative) = @_;
@@ -27,9 +29,9 @@ sub checkRelativeRefs {
     }
 
     if ($found_relative != $expect_relative) {
-        $Self->error("$file " .
-                     ($found_relative ? "has" : "does not have") .
-                     " relative variable references.");
+        error("$file " .
+              ($found_relative ? "has" : "does not have") .
+              " relative variable references.");
     }
 }
 
@@ -51,12 +53,12 @@ if ($Self->{vlt}) {
     checkRelativeRefs("l5__P2", 1);
 }
 
-execute (
-	 check_finished=>1,
-	 expect=>
+execute(
+    check_finished => 1,
+    expect =>
 '\] (%m|.*t\.ps): Clocked
 ',
-     );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_tree_inl0_pub1_norelcfuncs.pl b/test_regress/t/t_inst_tree_inl0_pub1_norelcfuncs.pl
index 4eec915b0..1b5c64c08 100755
--- a/test_regress/t/t_inst_tree_inl0_pub1_norelcfuncs.pl
+++ b/test_regress/t/t_inst_tree_inl0_pub1_norelcfuncs.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_tree.v");
 
-compile (
-	 verilator_flags2 => ['+define+NOUSE_INLINE', '+define+USE_PUBLIC', '--stats', '--norelative-cfuncs'],
-	 );
+compile(
+    verilator_flags2 => ['+define+NOUSE_INLINE', '+define+USE_PUBLIC', '--stats', '--norelative-cfuncs'],
+    );
 
 if ($Self->{vlt}) {
     # Fewer optimizations than t_inst_tree_inl0_pub1 which allows
@@ -25,17 +27,17 @@ if ($Self->{vlt}) {
         my $text = file_contents($file);
         $text =~ s/this->__VlSymsp//g;
         if ($text =~ m/this->/) {
-            $Self->error("$file has unexpected this-> refs when --norelative-cfuncs");
+            error("$file has unexpected this-> refs when --norelative-cfuncs");
         }
     }
 }
 
-execute (
-	 check_finished=>1,
-	 expect=>
+execute(
+    check_finished => 1,
+    expect =>
 '\] (%m|.*t\.ps): Clocked
 ',
-     );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_tree_inl1_pub0.pl b/test_regress/t/t_inst_tree_inl1_pub0.pl
index 001d36d28..fe266c45e 100755
--- a/test_regress/t/t_inst_tree_inl1_pub0.pl
+++ b/test_regress/t/t_inst_tree_inl1_pub0.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_tree.v");
 
-compile (
-	 v_flags2 => ['+define+USE_INLINE', '+define+NOUSE_PUBLIC'],
-	 );
+compile(
+    v_flags2 => ['+define+USE_INLINE', '+define+NOUSE_PUBLIC'],
+    );
 
-execute (
-	 check_finished=>1,
-	 expect=>
+execute(
+    check_finished => 1,
+    expect =>
 '\] (%m|.*t\.ps): Clocked
 ',
-     );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_tree_inl1_pub1.pl b/test_regress/t/t_inst_tree_inl1_pub1.pl
index d6905ac09..4d0910915 100755
--- a/test_regress/t/t_inst_tree_inl1_pub1.pl
+++ b/test_regress/t/t_inst_tree_inl1_pub1.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_inst_tree.v");
 
-compile (
-	 v_flags2 => ['+define+USE_INLINE', '+define+USE_PUBLIC'],
-	 );
+compile(
+    v_flags2 => ['+define+USE_INLINE', '+define+USE_PUBLIC'],
+    );
 
-execute (
-	 check_finished=>1,
-	 expect=>
+execute(
+    check_finished => 1,
+    expect =>
 '\] (%m|.*t\.ps): Clocked
 ',
-     );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_v2k.pl b/test_regress/t/t_inst_v2k.pl
index 1b4fa7124..42bec2a5b 100755
--- a/test_regress/t/t_inst_v2k.pl
+++ b/test_regress/t/t_inst_v2k.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ['+libext+.vi+.extranoneed'],
-	 nc => 0, # Error: Multiple +libext flags found
-	 vcs => 0,
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    v_flags2 => ['+libext+.vi+.extranoneed'],
+    nc => 0, # Error: Multiple +libext flags found
+    vcs => 0,
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_inst_wideconst.pl b/test_regress/t/t_inst_wideconst.pl
index fb2c8172c..60667b1d5 100755
--- a/test_regress/t/t_inst_wideconst.pl
+++ b/test_regress/t/t_inst_wideconst.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ['-public'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ['-public'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_interface.pl b/test_regress/t/t_interface.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_interface.pl
+++ b/test_regress/t/t_interface.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface1.pl b/test_regress/t/t_interface1.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface1.pl
+++ b/test_regress/t/t_interface1.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface1_modport.pl b/test_regress/t/t_interface1_modport.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface1_modport.pl
+++ b/test_regress/t/t_interface1_modport.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface1_modport_nansi.pl b/test_regress/t/t_interface1_modport_nansi.pl
index 13c82af1a..29c3e909c 100755
--- a/test_regress/t/t_interface1_modport_nansi.pl
+++ b/test_regress/t/t_interface1_modport_nansi.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface1_modport.v");
 
-compile (
+compile(
     v_flags2 => ['+define+NANSI'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface1_modport_noinl.pl b/test_regress/t/t_interface1_modport_noinl.pl
index f831022b7..a04b71dbe 100755
--- a/test_regress/t/t_interface1_modport_noinl.pl
+++ b/test_regress/t/t_interface1_modport_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface1_modport.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface1_modport_trace.pl b/test_regress/t/t_interface1_modport_trace.pl
index 103690b6b..336f9b7e8 100755
--- a/test_regress/t/t_interface1_modport_trace.pl
+++ b/test_regress/t/t_interface1_modport_trace.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface1_modport.v");
 
-compile (
+compile(
     verilator_flags2 => ['--trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface1_noinl.pl b/test_regress/t/t_interface1_noinl.pl
index 72b8fa56d..addef5226 100755
--- a/test_regress/t/t_interface1_noinl.pl
+++ b/test_regress/t/t_interface1_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface1.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface2.pl b/test_regress/t/t_interface2.pl
index 7ae28e6f7..ccc8e57db 100755
--- a/test_regress/t/t_interface2.pl
+++ b/test_regress/t/t_interface2.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--top-module t"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface2_noinl.pl b/test_regress/t/t_interface2_noinl.pl
index 88695127f..782f20df7 100755
--- a/test_regress/t/t_interface2_noinl.pl
+++ b/test_regress/t/t_interface2_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface2.v");
 
-compile (
+compile(
     verilator_flags2 => ["--top-module t -Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_array.pl b/test_regress/t/t_interface_array.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_interface_array.pl
+++ b/test_regress/t/t_interface_array.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_array_bad.pl b/test_regress/t/t_interface_array_bad.pl
index 1e9145239..292c6da02 100755
--- a/test_regress/t/t_interface_array_bad.pl
+++ b/test_regress/t/t_interface_array_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	fails=>1,
-	expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 '%Error: t/t_interface_array_bad.v:\d+: Expecting expression to be constant, but variable isn\'t const: bar
 %Error: t/t_interface_array_bad.v:\d+: Could not expand constant selection inside dotted reference: bar
 %Error: Exiting due to.*',
diff --git a/test_regress/t/t_interface_array_modport.pl b/test_regress/t/t_interface_array_modport.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_interface_array_modport.pl
+++ b/test_regress/t/t_interface_array_modport.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_array_nocolon.pl b/test_regress/t/t_interface_array_nocolon.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_interface_array_nocolon.pl
+++ b/test_regress/t/t_interface_array_nocolon.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_array_nocolon_bad.pl b/test_regress/t/t_interface_array_nocolon_bad.pl
index 75a5f7cc4..51241455e 100755
--- a/test_regress/t/t_interface_array_nocolon_bad.pl
+++ b/test_regress/t/t_interface_array_nocolon_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>$Self->{v3},
-    expect=>
+    fails => $Self->{vlt},
+    expect =>
 q{%Warning-LITENDIAN: t/t_interface_array_nocolon_bad.v:\d+: Little endian cell range connecting to vector: MSB < LSB of cell range: 0:2
 %Warning-LITENDIAN: Use [^\n]+
 %Warning-LITENDIAN: t/t_interface_array_nocolon_bad.v:\d+: Little endian cell range connecting to vector: MSB < LSB of cell range: 1:3
diff --git a/test_regress/t/t_interface_array_noinl.pl b/test_regress/t/t_interface_array_noinl.pl
index 043def6a7..740409044 100755
--- a/test_regress/t/t_interface_array_noinl.pl
+++ b/test_regress/t/t_interface_array_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_array.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_arraymux.pl b/test_regress/t/t_interface_arraymux.pl
index 086fa8d0c..62c359668 100755
--- a/test_regress/t/t_interface_arraymux.pl
+++ b/test_regress/t/t_interface_arraymux.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--lint-only"],
-    fails=>0,
+    fails => 0,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_interface_bind_public.pl b/test_regress/t/t_interface_bind_public.pl
index 231f356e9..60667b1d5 100755
--- a/test_regress/t/t_interface_bind_public.pl
+++ b/test_regress/t/t_interface_bind_public.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['-public'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down.pl b/test_regress/t/t_interface_down.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_down.pl
+++ b/test_regress/t/t_interface_down.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_gen.pl b/test_regress/t/t_interface_down_gen.pl
index c9f69ed2d..cc504c708 100755
--- a/test_regress/t/t_interface_down_gen.pl
+++ b/test_regress/t/t_interface_down_gen.pl
@@ -7,14 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, interface generates changing types");
-$Self->{vcs} and $Self->unsupported("Commercially unsupported, interface crossrefs");
+scenarios(simulator => 1);
+$Self->{vlt} and unsupported("Verilator unsupported, interface generates changing types");
+$Self->{vcs} and unsupported("Commercially unsupported, interface crossrefs");
 
-compile (
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_inla.pl b/test_regress/t/t_interface_down_inla.pl
index f65c1e7f8..091f1e378 100755
--- a/test_regress/t/t_interface_down_inla.pl
+++ b/test_regress/t/t_interface_down_inla.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_down.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_A'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_inlab.pl b/test_regress/t/t_interface_down_inlab.pl
index f06160436..d656df509 100755
--- a/test_regress/t/t_interface_down_inlab.pl
+++ b/test_regress/t/t_interface_down_inlab.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_down.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_A +define+INLINE_B'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_inlac.pl b/test_regress/t/t_interface_down_inlac.pl
index 6aae82408..1480307b8 100755
--- a/test_regress/t/t_interface_down_inlac.pl
+++ b/test_regress/t/t_interface_down_inlac.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_down.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_A +define+INLINE_C'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_inlad.pl b/test_regress/t/t_interface_down_inlad.pl
index 0addbdfe7..e406a91a9 100755
--- a/test_regress/t/t_interface_down_inlad.pl
+++ b/test_regress/t/t_interface_down_inlad.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_down.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_A +define+INLINE_D'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_inlb.pl b/test_regress/t/t_interface_down_inlb.pl
index b8e22f240..ed32d18c8 100755
--- a/test_regress/t/t_interface_down_inlb.pl
+++ b/test_regress/t/t_interface_down_inlb.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_down.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_B'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_inlbc.pl b/test_regress/t/t_interface_down_inlbc.pl
index 53d009068..42584154b 100755
--- a/test_regress/t/t_interface_down_inlbc.pl
+++ b/test_regress/t/t_interface_down_inlbc.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_down.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_B +define+INLINE_C'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_inlbd.pl b/test_regress/t/t_interface_down_inlbd.pl
index bdbf3392c..76a90e4c6 100755
--- a/test_regress/t/t_interface_down_inlbd.pl
+++ b/test_regress/t/t_interface_down_inlbd.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_down.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_B +define+INLINE_D'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_inlc.pl b/test_regress/t/t_interface_down_inlc.pl
index f8ffc151e..0c58dd9b8 100755
--- a/test_regress/t/t_interface_down_inlc.pl
+++ b/test_regress/t/t_interface_down_inlc.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_down.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_C'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_inlcd.pl b/test_regress/t/t_interface_down_inlcd.pl
index eb9218ec3..b5b9ae967 100755
--- a/test_regress/t/t_interface_down_inlcd.pl
+++ b/test_regress/t/t_interface_down_inlcd.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_down.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_C +define+INLINE_D'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_inld.pl b/test_regress/t/t_interface_down_inld.pl
index c57e458a8..2fb5e886f 100755
--- a/test_regress/t/t_interface_down_inld.pl
+++ b/test_regress/t/t_interface_down_inld.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_down.v");
 
-compile (
+compile(
     v_flags2 => ['+define+INLINE_D'],
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_down_noinl.pl b/test_regress/t/t_interface_down_noinl.pl
index d271830e1..2921a7686 100755
--- a/test_regress/t/t_interface_down_noinl.pl
+++ b/test_regress/t/t_interface_down_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_down.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen.pl b/test_regress/t/t_interface_gen.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen.pl
+++ b/test_regress/t/t_interface_gen.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen10.pl b/test_regress/t/t_interface_gen10.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen10.pl
+++ b/test_regress/t/t_interface_gen10.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen10_noinl.pl b/test_regress/t/t_interface_gen10_noinl.pl
index dda85f903..b2d964809 100755
--- a/test_regress/t/t_interface_gen10_noinl.pl
+++ b/test_regress/t/t_interface_gen10_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen10.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen11.pl b/test_regress/t/t_interface_gen11.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen11.pl
+++ b/test_regress/t/t_interface_gen11.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen11_noinl.pl b/test_regress/t/t_interface_gen11_noinl.pl
index 3afabd0a3..41dbe23b8 100755
--- a/test_regress/t/t_interface_gen11_noinl.pl
+++ b/test_regress/t/t_interface_gen11_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen11.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen12.pl b/test_regress/t/t_interface_gen12.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen12.pl
+++ b/test_regress/t/t_interface_gen12.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen12_noinl.pl b/test_regress/t/t_interface_gen12_noinl.pl
index 7c81d6ae7..1bde2074b 100755
--- a/test_regress/t/t_interface_gen12_noinl.pl
+++ b/test_regress/t/t_interface_gen12_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen12.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen2.pl b/test_regress/t/t_interface_gen2.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen2.pl
+++ b/test_regress/t/t_interface_gen2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen2_noinl.pl b/test_regress/t/t_interface_gen2_noinl.pl
index c0cffc8a4..60b79c8ea 100755
--- a/test_regress/t/t_interface_gen2_noinl.pl
+++ b/test_regress/t/t_interface_gen2_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen2.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen3.pl b/test_regress/t/t_interface_gen3.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen3.pl
+++ b/test_regress/t/t_interface_gen3.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen3_noinl.pl b/test_regress/t/t_interface_gen3_noinl.pl
index b684f4c48..423aae5dc 100755
--- a/test_regress/t/t_interface_gen3_noinl.pl
+++ b/test_regress/t/t_interface_gen3_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen3.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen4.pl b/test_regress/t/t_interface_gen4.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen4.pl
+++ b/test_regress/t/t_interface_gen4.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen4_noinl.pl b/test_regress/t/t_interface_gen4_noinl.pl
index 144ea2b45..130c1e314 100755
--- a/test_regress/t/t_interface_gen4_noinl.pl
+++ b/test_regress/t/t_interface_gen4_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen4.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen5.pl b/test_regress/t/t_interface_gen5.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen5.pl
+++ b/test_regress/t/t_interface_gen5.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen5_noinl.pl b/test_regress/t/t_interface_gen5_noinl.pl
index 1e8c1b963..ea149c55b 100755
--- a/test_regress/t/t_interface_gen5_noinl.pl
+++ b/test_regress/t/t_interface_gen5_noinl.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen5.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen6.pl b/test_regress/t/t_interface_gen6.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen6.pl
+++ b/test_regress/t/t_interface_gen6.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen6_noinl.pl b/test_regress/t/t_interface_gen6_noinl.pl
index d9fcdb8cd..63b10b62d 100755
--- a/test_regress/t/t_interface_gen6_noinl.pl
+++ b/test_regress/t/t_interface_gen6_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen6.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen7.pl b/test_regress/t/t_interface_gen7.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen7.pl
+++ b/test_regress/t/t_interface_gen7.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen7_noinl.pl b/test_regress/t/t_interface_gen7_noinl.pl
index 1a528a3c9..eb3a4b4bb 100755
--- a/test_regress/t/t_interface_gen7_noinl.pl
+++ b/test_regress/t/t_interface_gen7_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen7.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen8.pl b/test_regress/t/t_interface_gen8.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen8.pl
+++ b/test_regress/t/t_interface_gen8.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen8_noinl.pl b/test_regress/t/t_interface_gen8_noinl.pl
index a9d305113..7cc674f2b 100755
--- a/test_regress/t/t_interface_gen8_noinl.pl
+++ b/test_regress/t/t_interface_gen8_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen8.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen9.pl b/test_regress/t/t_interface_gen9.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_gen9.pl
+++ b/test_regress/t/t_interface_gen9.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen9_noinl.pl b/test_regress/t/t_interface_gen9_noinl.pl
index 05892eaab..c8a37074e 100755
--- a/test_regress/t/t_interface_gen9_noinl.pl
+++ b/test_regress/t/t_interface_gen9_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen9.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_gen_noinl.pl b/test_regress/t/t_interface_gen_noinl.pl
index 02cbccd29..3f5a8ebcb 100755
--- a/test_regress/t/t_interface_gen_noinl.pl
+++ b/test_regress/t/t_interface_gen_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_gen.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_inl.pl b/test_regress/t/t_interface_inl.pl
index ef9d007ba..a15b99c13 100755
--- a/test_regress/t/t_interface_inl.pl
+++ b/test_regress/t/t_interface_inl.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface.v");
 
-compile (
+compile(
     # Avoid inlining so we find bugs in the non-inliner connection code
     verilator_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_mismodport_bad.pl b/test_regress/t/t_interface_mismodport_bad.pl
index 3ff2dbd57..d5634a519 100755
--- a/test_regress/t/t_interface_mismodport_bad.pl
+++ b/test_regress/t/t_interface_mismodport_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
     fails => 1,
-    expect=>
+    expect =>
 '%Error: t/t_interface_mismodport_bad.v:\d+: Can\'t find definition of \'bad\' in dotted signal: isub.bad
 .*%Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_interface_missing_bad.pl b/test_regress/t/t_interface_missing_bad.pl
index a1b6d3a6f..5d14aaaa2 100755
--- a/test_regress/t/t_interface_missing_bad.pl
+++ b/test_regress/t/t_interface_missing_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	fails=>1,
-	expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 qr{%Error: t/t_interface_missing_bad.v:\d+: Cannot find file containing interface: foo_intf
 .*},
     );
diff --git a/test_regress/t/t_interface_modport.pl b/test_regress/t/t_interface_modport.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_modport.pl
+++ b/test_regress/t/t_interface_modport.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_modport_export.pl b/test_regress/t/t_interface_modport_export.pl
index 4bd751bc4..c10c500fa 100755
--- a/test_regress/t/t_interface_modport_export.pl
+++ b/test_regress/t/t_interface_modport_export.pl
@@ -7,13 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, bug696");
+scenarios(simulator => 1);
+$Self->{vlt} and unsupported("Verilator unsupported, bug696");
 
-compile (
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_modport_import.pl b/test_regress/t/t_interface_modport_import.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_interface_modport_import.pl
+++ b/test_regress/t/t_interface_modport_import.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_modport_import_noinl.pl b/test_regress/t/t_interface_modport_import_noinl.pl
index 00e0786c1..eb3847bf8 100755
--- a/test_regress/t/t_interface_modport_import_noinl.pl
+++ b/test_regress/t/t_interface_modport_import_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_modport_import.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_modport_inl.pl b/test_regress/t/t_interface_modport_inl.pl
index 57289dfd8..559f782ee 100755
--- a/test_regress/t/t_interface_modport_inl.pl
+++ b/test_regress/t/t_interface_modport_inl.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_modport.v");
 
-compile (
+compile(
     # Avoid inlining so we find bugs in the non-inliner connection code
     verilator_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_modport_noinl.pl b/test_regress/t/t_interface_modport_noinl.pl
index c5e3b48ef..d699c37b4 100755
--- a/test_regress/t/t_interface_modport_noinl.pl
+++ b/test_regress/t/t_interface_modport_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_modport.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_modportlist.pl b/test_regress/t/t_interface_modportlist.pl
index 9245a95fe..7053c9dd7 100755
--- a/test_regress/t/t_interface_modportlist.pl
+++ b/test_regress/t/t_interface_modportlist.pl
@@ -7,8 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    fails=>0,
+scenarios(simulator => 1);
+
+compile(
+    fails => 0,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_interface_mp_func.pl b/test_regress/t/t_interface_mp_func.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_interface_mp_func.pl
+++ b/test_regress/t/t_interface_mp_func.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_mp_func_noinl.pl b/test_regress/t/t_interface_mp_func_noinl.pl
index 0109caaa0..43973a543 100755
--- a/test_regress/t/t_interface_mp_func_noinl.pl
+++ b/test_regress/t/t_interface_mp_func_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_mp_func.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_nest.pl b/test_regress/t/t_interface_nest.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_interface_nest.pl
+++ b/test_regress/t/t_interface_nest.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_nest_noinl.pl b/test_regress/t/t_interface_nest_noinl.pl
index 1f9a9b2fe..e1ba7a75d 100755
--- a/test_regress/t/t_interface_nest_noinl.pl
+++ b/test_regress/t/t_interface_nest_noinl.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_nest.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_noinl.pl b/test_regress/t/t_interface_noinl.pl
index b40b905fb..4b521e5a0 100755
--- a/test_regress/t/t_interface_noinl.pl
+++ b/test_regress/t/t_interface_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_param1.pl b/test_regress/t/t_interface_param1.pl
index 1774aab4f..76bfa062d 100755
--- a/test_regress/t/t_interface_param1.pl
+++ b/test_regress/t/t_interface_param1.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_interface_param2.pl b/test_regress/t/t_interface_param2.pl
index b3f716e57..911d981d1 100755
--- a/test_regress/t/t_interface_param2.pl
+++ b/test_regress/t/t_interface_param2.pl
@@ -7,13 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, bug1104");
+scenarios(simulator => 1);
+$Self->{vlt} and unsupported("Verilator unsupported, bug1104");
 
-compile (
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_param_another_bad.pl b/test_regress/t/t_interface_param_another_bad.pl
index e0cefdebf..cbe619317 100755
--- a/test_regress/t/t_interface_param_another_bad.pl
+++ b/test_regress/t/t_interface_param_another_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	fails=>1,
-	expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 q{%Error: t/t_interface_param_another_bad.v:\d+: Parameter-resolved constants must not use dotted references: dummy
 %Error: Exiting due to.*},
     );
diff --git a/test_regress/t/t_interface_parameter_access.pl b/test_regress/t/t_interface_parameter_access.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_interface_parameter_access.pl
+++ b/test_regress/t/t_interface_parameter_access.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_size_bad.pl b/test_regress/t/t_interface_size_bad.pl
index 34a712410..e1c02a131 100755
--- a/test_regress/t/t_interface_size_bad.pl
+++ b/test_regress/t/t_interface_size_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	fails=>1,
-	expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 q{%Error: t/t_interface_size_bad.v:\d+: Illegal IFACEREF port connection 'foo', mismatch between port which is an interface array of size 5, and expression which is an interface array of size 4.
 %Error: t/t_interface_size_bad.v:\d+: Illegal IFACEREF port connection 'foo', mismatch between port which is an interface array of size 5, and expression which is an interface array of size 6.
 %Error: Exiting due to.*},
diff --git a/test_regress/t/t_interface_star.pl b/test_regress/t/t_interface_star.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_star.pl
+++ b/test_regress/t/t_interface_star.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_top_bad.pl b/test_regress/t/t_interface_top_bad.pl
index 34abb76b0..1fd71cfcd 100755
--- a/test_regress/t/t_interface_top_bad.pl
+++ b/test_regress/t/t_interface_top_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
     fails => 1,
-    expect=>
+    expect =>
 '%Error: t/t_interface_top_bad.v:\d+: Unsupported: Interfaced port on top level module',
     );
 
diff --git a/test_regress/t/t_interface_twod.pl b/test_regress/t/t_interface_twod.pl
index 1118f2e0e..1be18a66c 100755
--- a/test_regress/t/t_interface_twod.pl
+++ b/test_regress/t/t_interface_twod.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_twod_noinl.pl b/test_regress/t/t_interface_twod_noinl.pl
index ee9f4447e..af93c9ff2 100755
--- a/test_regress/t/t_interface_twod_noinl.pl
+++ b/test_regress/t/t_interface_twod_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_interface_twod.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_interface_typo_bad.pl b/test_regress/t/t_interface_typo_bad.pl
index 595301926..81d6fe926 100755
--- a/test_regress/t/t_interface_typo_bad.pl
+++ b/test_regress/t/t_interface_typo_bad.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
@@ -15,12 +17,12 @@ compile (
     fails => 1,
     # Used to be %Error: t/t_order_wireloop.v:\d+: Wire inputs its own output, creating circular logic .wire x=x.
     # However we no longer gate optimize this
-    expect=>
+    expect =>
 q{%Error: t/t_interface_typo_bad.v:\d+: Parent cell's interface is not found: foo_intf
 %Error: t/t_interface_typo_bad.v:\d+: Cannot find file containing interface: fo_intf
 %Error: t/t_interface_typo_bad.v:\d+: Found definition of 'the_foo' as a CELL but expected a variable
 .*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_interface_wrong_bad.pl b/test_regress/t/t_interface_wrong_bad.pl
index c773241b2..c97b5af9e 100755
--- a/test_regress/t/t_interface_wrong_bad.pl
+++ b/test_regress/t/t_interface_wrong_bad.pl
@@ -7,8 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    fails=>1,
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
     expect =>
 q{%Error: t/t_interface_wrong_bad.v:\d+: Port 'foo_port' expects 'foo_intf' interface but pin connects 'bar_intf' interface},
     );
diff --git a/test_regress/t/t_langext_1.pl b/test_regress/t/t_langext_1.pl
index 27eeba84b..6fb45726f 100755
--- a/test_regress/t/t_langext_1.pl
+++ b/test_regress/t/t_langext_1.pl
@@ -7,8 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # This is a compile only test.
-compile (
+compile(
     v_flags2 => ["+verilog2001ext+v"],
     );
 
diff --git a/test_regress/t/t_langext_1_bad.pl b/test_regress/t/t_langext_1_bad.pl
index 2a52c30b4..7cf98edc1 100755
--- a/test_regress/t/t_langext_1_bad.pl
+++ b/test_regress/t/t_langext_1_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_langext_1.v");
 
 # This is a compile only test.
-compile (
+compile(
     v_flags2 => ["+verilog1995ext+v"],
     fails => 1
     );
diff --git a/test_regress/t/t_langext_2.pl b/test_regress/t/t_langext_2.pl
index c4138df15..688ab8c39 100755
--- a/test_regress/t/t_langext_2.pl
+++ b/test_regress/t/t_langext_2.pl
@@ -7,8 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # This is a compile only test.
-compile (
+compile(
     v_flags2 => ["+systemverilogext+v"],
     );
 
diff --git a/test_regress/t/t_langext_2_bad.pl b/test_regress/t/t_langext_2_bad.pl
index b0c2df446..d60988f7b 100755
--- a/test_regress/t/t_langext_2_bad.pl
+++ b/test_regress/t/t_langext_2_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_langext_2.v");
 
 # This is a compile only test.
-compile (
+compile(
     v_flags2 => ["+1364-1995ext+v"],
     fails => 1
     );
diff --git a/test_regress/t/t_langext_3.pl b/test_regress/t/t_langext_3.pl
index 4a402cf79..7dee7e04c 100755
--- a/test_regress/t/t_langext_3.pl
+++ b/test_regress/t/t_langext_3.pl
@@ -7,8 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # This is a compile only test.
-compile (
+compile(
     v_flags2 => ["+1364-2005ext+v"],
     );
 
diff --git a/test_regress/t/t_langext_3_bad.pl b/test_regress/t/t_langext_3_bad.pl
index 760ff0d90..20abe2276 100755
--- a/test_regress/t/t_langext_3_bad.pl
+++ b/test_regress/t/t_langext_3_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_langext_3.v");
 
 # This is a compile only test.
-compile (
+compile(
     v_flags2 => ["+1364-2001ext+v"],
     fails => 1
     );
diff --git a/test_regress/t/t_langext_4.pl b/test_regress/t/t_langext_4.pl
index 0f1a1c416..c21cc0c2a 100755
--- a/test_regress/t/t_langext_4.pl
+++ b/test_regress/t/t_langext_4.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_langext_2.v");
 
 # This is a compile only test.
-compile (
+compile(
     v_flags2 => ["+1800-2009ext+v"],
     );
 
diff --git a/test_regress/t/t_langext_4_bad.pl b/test_regress/t/t_langext_4_bad.pl
index f8cc066ee..4552902ae 100755
--- a/test_regress/t/t_langext_4_bad.pl
+++ b/test_regress/t/t_langext_4_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_langext_2.v");
 
 # This is a compile only test.
-compile (
+compile(
     v_flags2 => ["+1800-2005ext+v"],
     fails => 1
     );
diff --git a/test_regress/t/t_leak.pl b/test_regress/t/t_leak.pl
index 7cf2ac161..da60e8024 100755
--- a/test_regress/t/t_leak.pl
+++ b/test_regress/t/t_leak.pl
@@ -7,16 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
-	 );
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
-execute (
-	 check_finished=>1,
-	 );
 ok(1);
 1;
diff --git a/test_regress/t/t_lint_always_comb_bad.pl b/test_regress/t/t_lint_always_comb_bad.pl
index 6361176b7..da46dbfa0 100755
--- a/test_regress/t/t_lint_always_comb_bad.pl
+++ b/test_regress/t/t_lint_always_comb_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
     fails => 1,
-    expect=>
+    expect =>
 '%Warning-ALWCOMBORDER: t/t_lint_always_comb_bad.v:\d+: Always_comb variable driven after use: mid
 .*%Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_lint_always_comb_iface.pl b/test_regress/t/t_lint_always_comb_iface.pl
index fcc84f672..3e882fd06 100755
--- a/test_regress/t/t_lint_always_comb_iface.pl
+++ b/test_regress/t/t_lint_always_comb_iface.pl
@@ -7,9 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
     fails => 0,
     verilator_make_gcc => 0,
diff --git a/test_regress/t/t_lint_blksync_bad.pl b/test_regress/t/t_lint_blksync_bad.pl
index e200eafa2..099a67126 100755
--- a/test_regress/t/t_lint_blksync_bad.pl
+++ b/test_regress/t/t_lint_blksync_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only -Wwarn-BLKSEQ -Wwarn-COMBDLY"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Warning-BLKSEQ: t/t_lint_blksync_bad.v:\d+: Blocking assignments \(=\) in sequential \(flop or latch\) block; suggest delayed assignments \(<=\).
 %Warning-BLKSEQ: Use .* to disable this message.
 %Warning-COMBDLY: t/t_lint_blksync_bad.v:\d+: Delayed assignments \(<=\) in non-clocked \(non flop or latch\) block; suggest blocking assignments \(=\).
diff --git a/test_regress/t/t_lint_blksync_loop.pl b/test_regress/t/t_lint_blksync_loop.pl
index 2d8ddfb24..303cd448e 100755
--- a/test_regress/t/t_lint_blksync_loop.pl
+++ b/test_regress/t/t_lint_blksync_loop.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     verilator_flags2 => ["--lint-only -Wwarn-BLKSEQ -Wwarn-COMBDLY"],
-    fails=>0,
+    fails => 0,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_lint_block_redecl_bad.pl b/test_regress/t/t_lint_block_redecl_bad.pl
index e70f3c89d..ec741a3b4 100755
--- a/test_regress/t/t_lint_block_redecl_bad.pl
+++ b/test_regress/t/t_lint_block_redecl_bad.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, bug485, false begin due to WHILE conversion blocks duplicate name detection");
+scenarios(vlt_all => 1);
+$Self->{vlt} and unsupported("Verilator unsupported, bug485, false begin due to WHILE conversion blocks duplicate name detection");
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Warning: duplicate...
 %Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_lint_bsspace_bad.pl b/test_regress/t/t_lint_bsspace_bad.pl
index d00d59f5a..17d16fe0b 100755
--- a/test_regress/t/t_lint_bsspace_bad.pl
+++ b/test_regress/t/t_lint_bsspace_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
+compile(
     verilator_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
     fails => 1,
-    expect=>
+    expect =>
 '%Warning-BSSPACE: t/t_lint_bsspace_bad.v:\d+: Backslash followed by whitespace, perhaps the whitespace is accidental\?
 .*%Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_lint_colonplus_bad.pl b/test_regress/t/t_lint_colonplus_bad.pl
index 0218109b6..7e04de051 100755
--- a/test_regress/t/t_lint_colonplus_bad.pl
+++ b/test_regress/t/t_lint_colonplus_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
+compile(
     verilator_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
     fails => 1,
-    expect=>
+    expect =>
 q{%Warning-COLONPLUS: t/t_lint_colonplus_bad.v:\d+: Perhaps instead of ':\+' the intent was '\+:'\?
 %Warning-COLONPLUS: Use .*
 .*%Error: Exiting due to.*},
diff --git a/test_regress/t/t_lint_comb_bad.pl b/test_regress/t/t_lint_comb_bad.pl
index cd289b1e6..0fca86935 100755
--- a/test_regress/t/t_lint_comb_bad.pl
+++ b/test_regress/t/t_lint_comb_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
+compile(
     verilator_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
     fails => 1,
-    expect=>
+    expect =>
 q{%Error: t/t_lint_comb_bad.v:\d+: syntax error, unexpected '@'
 .*},
     );
diff --git a/test_regress/t/t_lint_comb_use.pl b/test_regress/t/t_lint_comb_use.pl
index 85a93664d..be0635e49 100755
--- a/test_regress/t/t_lint_comb_use.pl
+++ b/test_regress/t/t_lint_comb_use.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     verilator_flags2 => ["--lint-only --bbox-sys"],
-    fails=>0,
+    fails => 0,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_lint_declfilename.pl b/test_regress/t/t_lint_declfilename.pl
index 82a626b50..cf67c444c 100755
--- a/test_regress/t/t_lint_declfilename.pl
+++ b/test_regress/t/t_lint_declfilename.pl
@@ -7,9 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_lint_declfilename_bad.pl b/test_regress/t/t_lint_declfilename_bad.pl
index 464a91fa7..8a977b032 100755
--- a/test_regress/t/t_lint_declfilename_bad.pl
+++ b/test_regress/t/t_lint_declfilename_bad.pl
@@ -7,17 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_lint_declfilename.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
+compile(
     v_flags2 => ["--lint-only -Wall"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Warning-DECLFILENAME: t/t_lint_declfilename.v:6: Filename \'t_lint_declfilename\' does not match MODULE name: t
 %Warning-DECLFILENAME: Use .* to disable this message.
 %Error: Exiting due to.*',
diff --git a/test_regress/t/t_lint_defparam.pl b/test_regress/t/t_lint_defparam.pl
index 82a626b50..cf67c444c 100755
--- a/test_regress/t/t_lint_defparam.pl
+++ b/test_regress/t/t_lint_defparam.pl
@@ -7,9 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_lint_defparam_bad.pl b/test_regress/t/t_lint_defparam_bad.pl
index 9449bdf40..d67cfc4d1 100755
--- a/test_regress/t/t_lint_defparam_bad.pl
+++ b/test_regress/t/t_lint_defparam_bad.pl
@@ -7,17 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_lint_defparam.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
+compile(
     v_flags2 => ["--lint-only -Wwarn-style -Wno-DECLFILENAME"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Warning-DEFPARAM: t/t_lint_defparam.v:\d+: Suggest replace defparam with Verilog 2001 #\(.P\(...etc...\)\)
 %Warning-DEFPARAM: Use .* to disable this message.
 %Error: Exiting due to.*',
diff --git a/test_regress/t/t_lint_ifdepth_bad.pl b/test_regress/t/t_lint_ifdepth_bad.pl
index 6f707bd57..3e3498652 100755
--- a/test_regress/t/t_lint_ifdepth_bad.pl
+++ b/test_regress/t/t_lint_ifdepth_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only -Wall -Wno-DECLFILENAME --if-depth 10"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Warning-IFDEPTH: t/t_lint_ifdepth_bad.v:\d+: Deep \'if\' statement; suggest unique/priority to avoid slow logic
 %Warning-IFDEPTH: Use .* to disable this message.
 %Error: Exiting due to.*',
diff --git a/test_regress/t/t_lint_implicit.pl b/test_regress/t/t_lint_implicit.pl
index 364eaa2cd..b757347fa 100755
--- a/test_regress/t/t_lint_implicit.pl
+++ b/test_regress/t/t_lint_implicit.pl
@@ -7,9 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     verilator_flags2 => ["-Wno-IMPLICIT"],
     );
 
diff --git a/test_regress/t/t_lint_implicit_bad.pl b/test_regress/t/t_lint_implicit_bad.pl
index 344ec2011..541b8f1e5 100755
--- a/test_regress/t/t_lint_implicit_bad.pl
+++ b/test_regress/t/t_lint_implicit_bad.pl
@@ -7,21 +7,21 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_lint_implicit.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 v_flags2 => ["--lint-only -Wwarn-IMPLICIT"],
-	 fails=>1,
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only -Wwarn-IMPLICIT"],
+    fails => 1,
+    expect =>
 '%Warning-IMPLICIT: t/t_lint_implicit.v:\d+: Signal definition not found, creating implicitly: b
 %Warning-IMPLICIT: Use .* to disable this message.
 %Warning-IMPLICIT: t/t_lint_implicit.v:\d+: Signal definition not found, creating implicitly: nt0
 %Warning-IMPLICIT: t/t_lint_implicit.v:\d+: Signal definition not found, creating implicitly: dummy1
 %Warning-IMPLICIT: t/t_lint_implicit.v:\d+: Signal definition not found, creating implicitly: dummy2
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_lint_implicit_def_bad.pl b/test_regress/t/t_lint_implicit_def_bad.pl
index 769ce18a8..9d74fa4f5 100755
--- a/test_regress/t/t_lint_implicit_def_bad.pl
+++ b/test_regress/t/t_lint_implicit_def_bad.pl
@@ -7,17 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 verilator_flags2 => ["--lint-only -Wall -Wno-DECLFILENAME"],
-	 fails=>1,
-	 expect=>
+compile(
+    verilator_flags2 => ["--lint-only -Wall -Wno-DECLFILENAME"],
+    fails => 1,
+    expect =>
 '%Warning-IMPLICIT: t/t_lint_implicit_def_bad.v:\d+: Signal definition not found, creating implicitly: imp_warn
 %Warning-IMPLICIT: Use "/\* verilator lint_off IMPLICIT \*/" and lint_on around source to disable this message.
 %Error: t/t_lint_implicit_def_bad.v:\d+: Signal definition not found, and implicit disabled with `default_nettype: imp_err
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_lint_implicit_port.pl b/test_regress/t/t_lint_implicit_port.pl
index a3f299571..b132612a8 100755
--- a/test_regress/t/t_lint_implicit_port.pl
+++ b/test_regress/t/t_lint_implicit_port.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 v_flags2 => ["-Wno-IMPLICIT"],
-	 );
+compile(
+    v_flags2 => ["-Wno-IMPLICIT"],
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_lint_incabspath.pl b/test_regress/t/t_lint_incabspath.pl
index 26120253e..decb90c06 100755
--- a/test_regress/t/t_lint_incabspath.pl
+++ b/test_regress/t/t_lint_incabspath.pl
@@ -7,9 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     verilator_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_lint_incabspath_bad.pl b/test_regress/t/t_lint_incabspath_bad.pl
index 35d72f42c..b5bafa4e5 100755
--- a/test_regress/t/t_lint_incabspath_bad.pl
+++ b/test_regress/t/t_lint_incabspath_bad.pl
@@ -7,17 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_lint_incabspath.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
+compile(
     v_flags2 => ["--lint-only -Wall -Wno-DECLFILENAME"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Warning-INCABSPATH: t/t_lint_incabspath.v:\d+: Suggest `include with absolute path be made relative, and use \+include: /dev/null
 %Warning-INCABSPATH: Use .* to disable this message.
 %Error: Exiting due to.*',
diff --git a/test_regress/t/t_lint_infinite.pl b/test_regress/t/t_lint_infinite.pl
index 21a15f49f..c717c1b23 100755
--- a/test_regress/t/t_lint_infinite.pl
+++ b/test_regress/t/t_lint_infinite.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
     make_top_shell => 0,
     make_main => 0,
     verilator_make_gcc => 0,
-    fails=>1,
-    expect=>
+    fails => 1,
+    expect =>
 '%Warning-INFINITELOOP: t/t_lint_infinite.v:\d+: Infinite loop \(condition always true\)
 %Warning-INFINITELOOP: Use .*
 %Warning-INFINITELOOP: t/t_lint_infinite.v:\d+: Infinite loop \(condition always true\)
diff --git a/test_regress/t/t_lint_inherit.pl b/test_regress/t/t_lint_inherit.pl
index 0e5fe81a4..5c448de7c 100755
--- a/test_regress/t/t_lint_inherit.pl
+++ b/test_regress/t/t_lint_inherit.pl
@@ -7,8 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
+
+compile(
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_lint_input_eq_bad.pl b/test_regress/t/t_lint_input_eq_bad.pl
index 6d78af529..baefcc57c 100755
--- a/test_regress/t/t_lint_input_eq_bad.pl
+++ b/test_regress/t/t_lint_input_eq_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Error: t/t_lint_input_eq_bad.v:\d+: Unsupported: Default value on module input: i2
 %Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_lint_latch_bad.pl b/test_regress/t/t_lint_latch_bad.pl
index 7de1109d7..518c711ae 100755
--- a/test_regress/t/t_lint_latch_bad.pl
+++ b/test_regress/t/t_lint_latch_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only -Wwarn-style -Wno-DECLFILENAME"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 quotemeta(
 '%Warning-COMBDLY: t/t_lint_latch_bad.v:24: Delayed assignments (<=) in non-clocked (non flop or latch) block; suggest blocking assignments (=).
 %Warning-COMBDLY: Use "/* verilator lint_off COMBDLY */" and lint_on around source to disable this message.
diff --git a/test_regress/t/t_lint_literal_bad.pl b/test_regress/t/t_lint_literal_bad.pl
index 68e60534c..6f2c81d8d 100755
--- a/test_regress/t/t_lint_literal_bad.pl
+++ b/test_regress/t/t_lint_literal_bad.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("Verilator only test") if !$Self->{vlt};
+scenarios(vlt_all => 1);
 
-compile (
-	 fails=>1,
-	 expect=>
+compile(
+    fails => 1,
+    expect =>
 '%Warning-WIDTH: t/t_lint_literal_bad.v:9: Value too large for 8 bit number: 256
 ',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_lint_modport_dir_bad.pl b/test_regress/t/t_lint_modport_dir_bad.pl
index cd0978837..5174323ac 100755
--- a/test_regress/t/t_lint_modport_dir_bad.pl
+++ b/test_regress/t/t_lint_modport_dir_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-#$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(simulator => 1);
 
-compile (
+compile(
     verilator_flags2 => ["--lint-only -Wno-DECLFILENAME"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Error: t/t_lint_modport_dir_bad.v:\d+: Attempt to drive input-only modport: signal
 %Error: Exiting due to .*',
     );
diff --git a/test_regress/t/t_lint_multidriven_bad.pl b/test_regress/t/t_lint_multidriven_bad.pl
index d4855bcb7..627ccd56d 100755
--- a/test_regress/t/t_lint_multidriven_bad.pl
+++ b/test_regress/t/t_lint_multidriven_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Warning-MULTIDRIVEN: t/t_lint_multidriven_bad.v:\d+: Signal has multiple driving blocks with different clocking: t.mem
 %Warning-MULTIDRIVEN: t/t_lint_multidriven_bad.v:\d+: ... Location of first driving block
 %Warning-MULTIDRIVEN: t/t_lint_multidriven_bad.v:\d+: ... Location of other driving block
diff --git a/test_regress/t/t_lint_once_bad.pl b/test_regress/t/t_lint_once_bad.pl
index 4a23f67b7..3a4d5630a 100755
--- a/test_regress/t/t_lint_once_bad.pl
+++ b/test_regress/t/t_lint_once_bad.pl
@@ -7,20 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--lint-only -Wwarn-UNUSED"],
-	 verilator_make_gcc => 0,
-	 fails=>1,
-	 expect=>
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--lint-only -Wwarn-UNUSED"],
+    verilator_make_gcc => 0,
+    fails => 1,
+    expect =>
 '%Warning-UNUSED: t/t_lint_once_bad.v:\d+: Signal is not driven, nor used: unus1
 %Warning-UNUSED: Use .* to disable this message.
 %Warning-UNUSED: t/t_lint_once_bad.v:\d+: Signal is not driven, nor used: unus2
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_lint_only.pl b/test_regress/t/t_lint_only.pl
index 140f40c44..c96b4b96e 100755
--- a/test_regress/t/t_lint_only.pl
+++ b/test_regress/t/t_lint_only.pl
@@ -7,19 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 v_flags2 => ["--lint-only"],
-	 verilator_make_gcc => 0,
-	 );
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    v_flags2 => ["--lint-only"],
+    verilator_make_gcc => 0,
+    );
 
 foreach my $file (glob("$Self->{obj_dir}/*t_lint_only*")) {
     next if $file =~ /simx_compile.log/;  # Made by driver.pl, not Verilator
     next if $file =~ /\.status/;  # Made by driver.pl, not Verilator
-    $Self->error("%Error: Created $file, but --lint-only shouldn't create files");
+    error("%Error: Created $file, but --lint-only shouldn't create files");
 }
 
 ok(1);
diff --git a/test_regress/t/t_lint_pindup_bad.pl b/test_regress/t/t_lint_pindup_bad.pl
index 3cde70704..3015d3519 100755
--- a/test_regress/t/t_lint_pindup_bad.pl
+++ b/test_regress/t/t_lint_pindup_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Error: t/t_lint_pindup_bad.v:\d+: Duplicate pin connection: i
 %Error: t/t_lint_pindup_bad.v:\d+: ... Location of original pin connection
 %Error: t/t_lint_pindup_bad.v:\d+: Pin not found: __pinNumber4
diff --git a/test_regress/t/t_lint_pkg_colon_bad.pl b/test_regress/t/t_lint_pkg_colon_bad.pl
index 862dec3bc..1a04c85a0 100755
--- a/test_regress/t/t_lint_pkg_colon_bad.pl
+++ b/test_regress/t/t_lint_pkg_colon_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=> quotemeta(
+    expect => quotemeta(
 qq{%Error: t/t_lint_pkg_colon_bad.v:6: syntax error, unexpected ::, expecting ')' or ','
 %Error: t/t_lint_pkg_colon_bad.v:6: Perhaps 'mispkg' is a package which needs to be predeclared? (IEEE 2017 26.3)
 %Error: t/t_lint_pkg_colon_bad.v:7: syntax error, unexpected ::, expecting ',' or ';'
diff --git a/test_regress/t/t_lint_realcvt_bad.pl b/test_regress/t/t_lint_realcvt_bad.pl
index d2bd9db35..40a534f14 100755
--- a/test_regress/t/t_lint_realcvt_bad.pl
+++ b/test_regress/t/t_lint_realcvt_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 v_flags2 => ["--lint-only -Wwarn-REALCVT"],
-	 verilator_make_gcc => 0,
-	 fails=>1,
-	 expect=>
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    v_flags2 => ["--lint-only -Wwarn-REALCVT"],
+    verilator_make_gcc => 0,
+    fails => 1,
+    expect =>
 '%Warning-REALCVT: t/t_lint_realcvt_bad.v:\d+: Implicit conversion of real to integer
 %Warning-REALCVT: Use .* to disable this message.
 %Error: Exiting due to.*',
diff --git a/test_regress/t/t_lint_repeat_bad.pl b/test_regress/t/t_lint_repeat_bad.pl
index 8dbdf5e19..ed667e7ea 100755
--- a/test_regress/t/t_lint_repeat_bad.pl
+++ b/test_regress/t/t_lint_repeat_bad.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Warning-WIDTH: t/t_lint_repeat_bad.v:17: Operator ASSIGNW expects 1 bits on the Assign RHS, but Assign RHS's VARREF 'a' generates 2 bits.
 %Warning-WIDTH: Use \"\/\* verilator lint_off WIDTH \*\/\" and lint_on around source to disable this message.
 %Error: Exiting due to 1 warning}
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_lint_restore_bad.pl b/test_regress/t/t_lint_restore_bad.pl
index 3e03b32e8..854be8e74 100755
--- a/test_regress/t/t_lint_restore_bad.pl
+++ b/test_regress/t/t_lint_restore_bad.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{.*%Warning-WIDTH: t/t_lint_restore_bad.v:\d+: Operator ASSIGN expects 5 bits on the Assign RHS, but Assign RHS's CONST '64'h1' generates 64 bits.
 %Warning-WIDTH: Use .*
 %Error: Exiting due to.*},
diff --git a/test_regress/t/t_lint_setout_bad.pl b/test_regress/t/t_lint_setout_bad.pl
index f37983304..a59e415d5 100755
--- a/test_regress/t/t_lint_setout_bad.pl
+++ b/test_regress/t/t_lint_setout_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Error: t/t_lint_setout_bad.v:\d+: Output port is connected to a constant pin, electrical short
 .*',
     );
diff --git a/test_regress/t/t_lint_setout_bad_noinl.pl b/test_regress/t/t_lint_setout_bad_noinl.pl
index 9d574be3a..f1d9328ed 100755
--- a/test_regress/t/t_lint_setout_bad_noinl.pl
+++ b/test_regress/t/t_lint_setout_bad_noinl.pl
@@ -7,17 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_lint_setout_bad.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
+compile(
     v_flags2 => ["--lint-only -Oi"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Error: t/t_lint_setout_bad.v:\d+: Output port is connected to a constant pin, electrical short
 .*',
     );
diff --git a/test_regress/t/t_lint_syncasyncnet_bad.pl b/test_regress/t/t_lint_syncasyncnet_bad.pl
index 0864e64c2..e907c3f4a 100755
--- a/test_regress/t/t_lint_syncasyncnet_bad.pl
+++ b/test_regress/t/t_lint_syncasyncnet_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only -Wall -Wno-DECLFILENAME --if-depth 10"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Warning-SYNCASYNCNET: t/t_lint_syncasyncnet_bad.v:\d+: Signal flopped as both synchronous and async: rst_both_l
 %Warning-SYNCASYNCNET: t/t_lint_syncasyncnet_bad.v:\d+: ... Location of async usage
 %Warning-SYNCASYNCNET: t/t_lint_syncasyncnet_bad.v:\d+: ... Location of sync usage
diff --git a/test_regress/t/t_lint_unsized_bad.pl b/test_regress/t/t_lint_unsized_bad.pl
index f9b683e90..96c9046aa 100755
--- a/test_regress/t/t_lint_unsized_bad.pl
+++ b/test_regress/t/t_lint_unsized_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=> quotemeta(
+    expect => quotemeta(
 qq{%Error: t/t_lint_unsized_bad.v:7: Too many digits for 32 bit number: 'd123456789123456789123456789
 %Error: t/t_lint_unsized_bad.v:7: As that number was unsized ('d...) it is limited to 32 bits (IEEE 2017 5.7.1)
 }).'%Error: Exiting due to.*'
diff --git a/test_regress/t/t_lint_unsup_deassign.pl b/test_regress/t/t_lint_unsup_deassign.pl
index 3aea080dd..e7cbe69d1 100755
--- a/test_regress/t/t_lint_unsup_deassign.pl
+++ b/test_regress/t/t_lint_unsup_deassign.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only --bbox-unsup"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_lint_unsup_mixed.pl b/test_regress/t/t_lint_unsup_mixed.pl
index 3aea080dd..e7cbe69d1 100755
--- a/test_regress/t/t_lint_unsup_mixed.pl
+++ b/test_regress/t/t_lint_unsup_mixed.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only --bbox-unsup"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_lint_unused.pl b/test_regress/t/t_lint_unused.pl
index 1deb80a7b..07151b701 100755
--- a/test_regress/t/t_lint_unused.pl
+++ b/test_regress/t/t_lint_unused.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only --bbox-sys --bbox-unsup -Wall -Wno-DECLFILENAME"],
-    fails=>0,
+    fails => 0,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_lint_unused.v b/test_regress/t/t_lint_unused.v
index ad4a23147..637f3cce7 100644
--- a/test_regress/t/t_lint_unused.v
+++ b/test_regress/t/t_lint_unused.v
@@ -3,6 +3,8 @@
 // This file ONLY is placed into the Public Domain, for any use,
 // without warranty, 2010 by Wilson Snyder.
 
+`define STRINGIFY(x) `"x`"
+
 module t (/*AUTOARG*/
    // Outputs
    out,
@@ -26,10 +28,10 @@ module t (/*AUTOARG*/
    integer infile;
    integer outfile;
    initial begin
-      outfile = $fopen("obj_dir/t_lint_unused_bad/open.log", "w");
+      outfile = $fopen({`STRINGIFY(`TEST_OBJ_DIR),"/open.log"}, "w");
       $fwrite(outfile, "1\n");
       $fclose(outfile);
-      infile = $fopen("obj_dir/t_lint_unused_bad/open.log", "r");
+      infile = $fopen({`STRINGIFY(`TEST_OBJ_DIR),"/open.log"}, "r");
       if ($fgetc(infile) != "1") begin end
    end
 
diff --git a/test_regress/t/t_lint_unused_bad.pl b/test_regress/t/t_lint_unused_bad.pl
index e97e36607..4def8e938 100755
--- a/test_regress/t/t_lint_unused_bad.pl
+++ b/test_regress/t/t_lint_unused_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only --bbox-sys --bbox-unsup -Wall -Wno-DECLFILENAME"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Warning-UNUSED: t/t_lint_unused_bad.v:\d+: Bits of signal are not used: assunu1\[5:1\]
 %Warning-UNUSED: Use .* to disable this message.
 %Warning-UNDRIVEN: t/t_lint_unused_bad.v:\d+: Bits of signal are not driven: udrb2\[14:13,11\]
diff --git a/test_regress/t/t_lint_unused_iface.pl b/test_regress/t/t_lint_unused_iface.pl
index 6fff7520d..053e32067 100755
--- a/test_regress/t/t_lint_unused_iface.pl
+++ b/test_regress/t/t_lint_unused_iface.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--lint-only -Wall -Wno-DECLFILENAME"],
-    fails=>0,
+    fails => 0,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_lint_unused_iface_bad.pl b/test_regress/t/t_lint_unused_iface_bad.pl
index 0b7b75685..0859fbe9e 100755
--- a/test_regress/t/t_lint_unused_iface_bad.pl
+++ b/test_regress/t/t_lint_unused_iface_bad.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     verilator_flags2 => ["--lint-only -Wall -Wno-DECLFILENAME"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_lint_width.pl b/test_regress/t/t_lint_width.pl
index a823b8d70..09495b14b 100755
--- a/test_regress/t/t_lint_width.pl
+++ b/test_regress/t/t_lint_width.pl
@@ -7,13 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_make_gcc => 0,
+compile(
+    v_flags2 => ["--lint-only"],
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_make_gcc => 0,
     );
 
 ok(1);
diff --git a/test_regress/t/t_lint_width_bad.pl b/test_regress/t/t_lint_width_bad.pl
index c3abd847a..13284af33 100755
--- a/test_regress/t/t_lint_width_bad.pl
+++ b/test_regress/t/t_lint_width_bad.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{.*%Warning-WIDTH: t/t_lint_width_bad.v:\d+: Operator VAR 'XS' expects 4 bits on the Initial value, but Initial value's CONST '\?32\?bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx' generates 32 bits.
 %Warning-WIDTH: Use .*
 %Warning-WIDTH: t/t_lint_width_bad.v:\d+: Operator ASSIGNW expects 5 bits on the Assign RHS, but Assign RHS's VARREF 'in' generates 4 bits.
diff --git a/test_regress/t/t_math_arith.pl b/test_regress/t/t_math_arith.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_arith.pl
+++ b/test_regress/t/t_math_arith.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_clog2.pl b/test_regress/t/t_math_clog2.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_clog2.pl
+++ b/test_regress/t/t_math_clog2.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_cmp.pl b/test_regress/t/t_math_cmp.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_cmp.pl
+++ b/test_regress/t/t_math_cmp.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_concat.pl b/test_regress/t/t_math_concat.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_concat.pl
+++ b/test_regress/t/t_math_concat.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_concat0.pl b/test_regress/t/t_math_concat0.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_concat0.pl
+++ b/test_regress/t/t_math_concat0.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_concat64.pl b/test_regress/t/t_math_concat64.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_concat64.pl
+++ b/test_regress/t/t_math_concat64.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_cond_huge.pl b/test_regress/t/t_math_cond_huge.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_cond_huge.pl
+++ b/test_regress/t/t_math_cond_huge.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_const.pl b/test_regress/t/t_math_const.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_const.pl
+++ b/test_regress/t/t_math_const.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_div.pl b/test_regress/t/t_math_div.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_div.pl
+++ b/test_regress/t/t_math_div.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_div0.pl b/test_regress/t/t_math_div0.pl
index 566b77252..525dd83c5 100755
--- a/test_regress/t/t_math_div0.pl
+++ b/test_regress/t/t_math_div0.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--x-assign 0'],
     );
 
-execute (
+execute(
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_divw.pl b/test_regress/t/t_math_divw.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_divw.pl
+++ b/test_regress/t/t_math_divw.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_eq.pl b/test_regress/t/t_math_eq.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_eq.pl
+++ b/test_regress/t/t_math_eq.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_equal.pl b/test_regress/t/t_math_equal.pl
index 29bf04d49..b1acebe26 100755
--- a/test_regress/t/t_math_equal.pl
+++ b/test_regress/t/t_math_equal.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_imm.pl b/test_regress/t/t_math_imm.pl
index dccd4cf50..803dca735 100755
--- a/test_regress/t/t_math_imm.pl
+++ b/test_regress/t/t_math_imm.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ["--compiler msvc"],  # We have deep expressions we want to test
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ["--compiler msvc"],  # We have deep expressions we want to test
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_imm2.pl b/test_regress/t/t_math_imm2.pl
index e20a5c521..da60e8024 100755
--- a/test_regress/t/t_math_imm2.pl
+++ b/test_regress/t/t_math_imm2.pl
@@ -7,17 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("Verilator only test") if !$Self->{vlt};
+scenarios(vlt_all => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
-	 );
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_msvc_64.pl b/test_regress/t/t_math_msvc_64.pl
index 8cd1847cb..4780ffb2e 100755
--- a/test_regress/t/t_math_msvc_64.pl
+++ b/test_regress/t/t_math_msvc_64.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ["--compiler msvc"],  # Bug requires msvc
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ["--compiler msvc"],  # Bug requires msvc
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_mul.pl b/test_regress/t/t_math_mul.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_mul.pl
+++ b/test_regress/t/t_math_mul.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_pick.pl b/test_regress/t/t_math_pick.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_pick.pl
+++ b/test_regress/t/t_math_pick.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_pow.pl b/test_regress/t/t_math_pow.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_pow.pl
+++ b/test_regress/t/t_math_pow.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_pow2.pl b/test_regress/t/t_math_pow2.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_pow2.pl
+++ b/test_regress/t/t_math_pow2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_pow3.pl b/test_regress/t/t_math_pow3.pl
index 5ebc6a457..89a4e77d9 100755
--- a/test_regress/t/t_math_pow3.pl
+++ b/test_regress/t/t_math_pow3.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_pow4.pl b/test_regress/t/t_math_pow4.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_pow4.pl
+++ b/test_regress/t/t_math_pow4.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_pow5.pl b/test_regress/t/t_math_pow5.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_pow5.pl
+++ b/test_regress/t/t_math_pow5.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_pow6.pl b/test_regress/t/t_math_pow6.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_pow6.pl
+++ b/test_regress/t/t_math_pow6.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_precedence.pl b/test_regress/t/t_math_precedence.pl
index df1a10d7b..2eff63c2b 100755
--- a/test_regress/t/t_math_precedence.pl
+++ b/test_regress/t/t_math_precedence.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-#!$Self->{vcs} or $Self->unsupported("VCS does ** wrong, fixed in 2014");
+scenarios(simulator => 1);
 
-compile (
-	 );
+#!$Self->{vcs} or unsupported("VCS does ** wrong, fixed in 2014");
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_real.pl b/test_regress/t/t_math_real.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_real.pl
+++ b/test_regress/t/t_math_real.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_real_public.pl b/test_regress/t/t_math_real_public.pl
index f6b472c39..b362560d5 100755
--- a/test_regress/t/t_math_real_public.pl
+++ b/test_regress/t/t_math_real_public.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--cc --public'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_repl.pl b/test_regress/t/t_math_repl.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_repl.pl
+++ b/test_regress/t/t_math_repl.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_reverse.pl b/test_regress/t/t_math_reverse.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_reverse.pl
+++ b/test_regress/t/t_math_reverse.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_shift.pl b/test_regress/t/t_math_shift.pl
index b8f89b85c..0a3b50107 100755
--- a/test_regress/t/t_math_shift.pl
+++ b/test_regress/t/t_math_shift.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    verilator_flags2 => ["-Wno-CLKDATA"]
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ["-Wno-CLKDATA"]
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_shift_over_bad.pl b/test_regress/t/t_math_shift_over_bad.pl
index e579e55f5..0b8bbaaaa 100755
--- a/test_regress/t/t_math_shift_over_bad.pl
+++ b/test_regress/t/t_math_shift_over_bad.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     verilator_flags2 => ["--lint-only"],
-    fails=>1,
-    expect=>
+    fails => 1,
+    expect =>
 '%Error: Internal Error: .*: Value too wide for 32-bits expected in this context 64\'h123456789abcdef
 .',
     );
diff --git a/test_regress/t/t_math_shift_rep.pl b/test_regress/t/t_math_shift_rep.pl
index 451cd7e39..426086634 100755
--- a/test_regress/t/t_math_shift_rep.pl
+++ b/test_regress/t/t_math_shift_rep.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["-CFLAGS '-DVL_DEBUG -ggdb -O0'"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_shift_sel.pl b/test_regress/t/t_math_shift_sel.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_shift_sel.pl
+++ b/test_regress/t/t_math_shift_sel.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_shiftrs.pl b/test_regress/t/t_math_shiftrs.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_shiftrs.pl
+++ b/test_regress/t/t_math_shiftrs.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_sign_extend.pl b/test_regress/t/t_math_sign_extend.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_sign_extend.pl
+++ b/test_regress/t/t_math_sign_extend.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_signed.pl b/test_regress/t/t_math_signed.pl
index 5ebc6a457..89a4e77d9 100755
--- a/test_regress/t/t_math_signed.pl
+++ b/test_regress/t/t_math_signed.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_signed2.pl b/test_regress/t/t_math_signed2.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_signed2.pl
+++ b/test_regress/t/t_math_signed2.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_signed3.pl b/test_regress/t/t_math_signed3.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_signed3.pl
+++ b/test_regress/t/t_math_signed3.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_signed4.pl b/test_regress/t/t_math_signed4.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_signed4.pl
+++ b/test_regress/t/t_math_signed4.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_signed5.pl b/test_regress/t/t_math_signed5.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_signed5.pl
+++ b/test_regress/t/t_math_signed5.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_signed6.pl b/test_regress/t/t_math_signed6.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_signed6.pl
+++ b/test_regress/t/t_math_signed6.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_signed7.pl b/test_regress/t/t_math_signed7.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_signed7.pl
+++ b/test_regress/t/t_math_signed7.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_signed_wire.pl b/test_regress/t/t_math_signed_wire.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_signed_wire.pl
+++ b/test_regress/t/t_math_signed_wire.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_math_strwidth.pl b/test_regress/t/t_math_strwidth.pl
index 1db556bfe..1e3d87b0b 100755
--- a/test_regress/t/t_math_strwidth.pl
+++ b/test_regress/t/t_math_strwidth.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => [],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    v_flags2 => [],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_svl.pl b/test_regress/t/t_math_svl.pl
index b3f97d2a2..d10857db2 100755
--- a/test_regress/t/t_math_svl.pl
+++ b/test_regress/t/t_math_svl.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-	 check_finished=>1,
-	 # Make sure we get the finish statement called
-	 expect=>
+execute(
+    check_finished => 1,
+    # Make sure we get the finish statement called
+    expect =>
 '\*-\* All Finished \*-\*
 Goodbye world, at cycle \d+.*',
     );
diff --git a/test_regress/t/t_math_svl2.pl b/test_regress/t/t_math_svl2.pl
index 04b66db54..aa70994c6 100755
--- a/test_regress/t/t_math_svl2.pl
+++ b/test_regress/t/t_math_svl2.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_swap.pl b/test_regress/t/t_math_swap.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_swap.pl
+++ b/test_regress/t/t_math_swap.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_synmul.pl b/test_regress/t/t_math_synmul.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_synmul.pl
+++ b/test_regress/t/t_math_synmul.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_tri.pl b/test_regress/t/t_math_tri.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_tri.pl
+++ b/test_regress/t/t_math_tri.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_trig.pl b/test_regress/t/t_math_trig.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_trig.pl
+++ b/test_regress/t/t_math_trig.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_vgen.pl b/test_regress/t/t_math_vgen.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_vgen.pl
+++ b/test_regress/t/t_math_vgen.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_vliw.pl b/test_regress/t/t_math_vliw.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_math_vliw.pl
+++ b/test_regress/t/t_math_vliw.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_math_width.pl b/test_regress/t/t_math_width.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_math_width.pl
+++ b/test_regress/t/t_math_width.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mem.pl b/test_regress/t/t_mem.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_mem.pl
+++ b/test_regress/t/t_mem.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_banks.pl b/test_regress/t/t_mem_banks.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_mem_banks.pl
+++ b/test_regress/t/t_mem_banks.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mem_cond.pl b/test_regress/t/t_mem_cond.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_mem_cond.pl
+++ b/test_regress/t/t_mem_cond.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mem_fifo.pl b/test_regress/t/t_mem_fifo.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_mem_fifo.pl
+++ b/test_regress/t/t_mem_fifo.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_file.pl b/test_regress/t/t_mem_file.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_mem_file.pl
+++ b/test_regress/t/t_mem_file.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_first.pl b/test_regress/t/t_mem_first.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_mem_first.pl
+++ b/test_regress/t/t_mem_first.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_func.pl b/test_regress/t/t_mem_func.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_mem_func.pl
+++ b/test_regress/t/t_mem_func.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_iforder.pl b/test_regress/t/t_mem_iforder.pl
index fd76d2220..1be18a66c 100755
--- a/test_regress/t/t_mem_iforder.pl
+++ b/test_regress/t/t_mem_iforder.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_multi_io.pl b/test_regress/t/t_mem_multi_io.pl
index 886fe42af..6ab567600 100755
--- a/test_regress/t/t_mem_multi_io.pl
+++ b/test_regress/t/t_mem_multi_io.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 # Disable inlining, this test is trivial without it
-	 verilator_flags2 => ["-Oi --trace"],
-	 verilator_flags3 => [],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    # Disable inlining, this test is trivial without it
+    verilator_flags2 => ["-Oi --trace"],
+    verilator_flags3 => [],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_multi_io2_cc.pl b/test_regress/t/t_mem_multi_io2_cc.pl
index c52d2027e..83a749623 100755
--- a/test_regress/t/t_mem_multi_io2_cc.pl
+++ b/test_regress/t/t_mem_multi_io2_cc.pl
@@ -7,19 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_mem_multi_io2.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_mem_multi_io2.cpp -Oi"],
-	 verilator_flags3 => [],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_mem_multi_io2.cpp -Oi"],
+    verilator_flags3 => [],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mem_multi_io2_sc.pl b/test_regress/t/t_mem_multi_io2_sc.pl
index 24a2f0b76..e5d7f745b 100755
--- a/test_regress/t/t_mem_multi_io2_sc.pl
+++ b/test_regress/t/t_mem_multi_io2_sc.pl
@@ -7,18 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_mem_multi_io2.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_mem_multi_io2.cpp --sc -Oi"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_mem_multi_io2.cpp --sc -Oi"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mem_multi_io3_cc.pl b/test_regress/t/t_mem_multi_io3_cc.pl
index e1509c512..57f12c140 100755
--- a/test_regress/t/t_mem_multi_io3_cc.pl
+++ b/test_regress/t/t_mem_multi_io3_cc.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_mem_multi_io3.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_mem_multi_io3.cpp -Oi"],
-	 verilator_flags3 => [],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_mem_multi_io3.cpp -Oi"],
+    verilator_flags3 => [],
     );
 
 ok(1);
diff --git a/test_regress/t/t_mem_multi_io3_sc.pl b/test_regress/t/t_mem_multi_io3_sc.pl
index 19cfbc9d4..1ecc7694f 100755
--- a/test_regress/t/t_mem_multi_io3_sc.pl
+++ b/test_regress/t/t_mem_multi_io3_sc.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_mem_multi_io3.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_mem_multi_io3.cpp --sc -Oi"],
-	 verilator_flags3 => [],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_mem_multi_io3.cpp --sc -Oi"],
+    verilator_flags3 => [],
     );
 
 ok(1);
diff --git a/test_regress/t/t_mem_multi_ref_bad.pl b/test_regress/t/t_mem_multi_ref_bad.pl
index c61061ba7..8f8522429 100755
--- a/test_regress/t/t_mem_multi_ref_bad.pl
+++ b/test_regress/t/t_mem_multi_ref_bad.pl
@@ -7,17 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 fails=>$Self->{v3},
-	 nc=>0,  # Need to get it not to give the prompt
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => $Self->{vlt},
+    nc => 0,  # Need to get it not to give the prompt
+    expect =>
 q{%Error: t/t_mem_multi_ref_bad.v:\d+: Illegal bit or array select; type does not have a bit range, or bad dimension: type is (bit|logic)
 .*%Error: t/t_mem_multi_ref_bad.v:\d+: Illegal bit or array select; type does not have a bit range, or bad dimension: type is (bit|logic)
 .*%Error: t/t_mem_multi_ref_bad.v:\d+: Illegal bit or array select; type does not have a bit range, or bad dimension: type is (bit|logic)
 .*%Error: t/t_mem_multi_ref_bad.v:\d+: Illegal \+: or -: select; type already selected, or bad dimension: type is UNPACKARRAYDTYPE
 .*%Error: t/t_mem_multi_ref_bad.v:\d+: Illegal bit or array select; type does not have a bit range, or bad dimension: type is logic
 .*%Error: Exiting due to.*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_multidim.pl b/test_regress/t/t_mem_multidim.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_mem_multidim.pl
+++ b/test_regress/t/t_mem_multidim.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_multidim_Ox.pl b/test_regress/t/t_mem_multidim_Ox.pl
index 2c4a0b665..31172a9fc 100755
--- a/test_regress/t/t_mem_multidim_Ox.pl
+++ b/test_regress/t/t_mem_multidim_Ox.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_mem_multidim.v");
 
-compile (
-	 verilator_flags2 => ['--Ox'],
-	 );
+compile(
+    verilator_flags2 => ['--Ox'],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_multidim_trace.pl b/test_regress/t/t_mem_multidim_trace.pl
index b8a04271d..e337974fe 100755
--- a/test_regress/t/t_mem_multidim_trace.pl
+++ b/test_regress/t/t_mem_multidim_trace.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_mem_multidim.v");
 
-compile (
-	 verilator_flags2 => ['--cc --trace'],
-	 );
+compile(
+    verilator_flags2 => ['--cc --trace'],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_multiwire.pl b/test_regress/t/t_mem_multiwire.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_mem_multiwire.pl
+++ b/test_regress/t/t_mem_multiwire.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_packed.pl b/test_regress/t/t_mem_packed.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_mem_packed.pl
+++ b/test_regress/t/t_mem_packed.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_packed_assign.pl b/test_regress/t/t_mem_packed_assign.pl
index 9ae333078..ede6d329a 100755
--- a/test_regress/t/t_mem_packed_assign.pl
+++ b/test_regress/t/t_mem_packed_assign.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mem_packed_bad.pl b/test_regress/t/t_mem_packed_bad.pl
index dc42ba5b8..96651ae1c 100755
--- a/test_regress/t/t_mem_packed_bad.pl
+++ b/test_regress/t/t_mem_packed_bad.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 verilator_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+compile(
+    verilator_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Error: t/t_mem_packed_bad.v:\d+: CONST '28'h0' unexpected in assignment to unpacked array
 %Error: Exiting due to.*},
     );
diff --git a/test_regress/t/t_mem_shift.pl b/test_regress/t/t_mem_shift.pl
index 1cb7de21a..752d4c34f 100755
--- a/test_regress/t/t_mem_shift.pl
+++ b/test_regress/t/t_mem_shift.pl
@@ -7,17 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ["--stats"],
-	 );
+scenarios(simulator => 1);
+
+compile(
+    verilator_flags2 => ["--stats"],
+    );
 
 if ($Self->{vlt}) {
     file_grep ($Self->{stats}, qr/Optimizations, Delayed shared-sets\s+(\d+)/i, 14);
 }
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_slice.pl b/test_regress/t/t_mem_slice.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_mem_slice.pl
+++ b/test_regress/t/t_mem_slice.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mem_slice_bad.pl b/test_regress/t/t_mem_slice_bad.pl
index 0d06abd76..9ae1f10e9 100755
--- a/test_regress/t/t_mem_slice_bad.pl
+++ b/test_regress/t/t_mem_slice_bad.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 q{%Error: t/t_mem_slice_bad.v:\d+: Slice selection index '\[2:0\]' outside data type's '\[1:0\]'
 %Error: t/t_mem_slice_bad.v:\d+: Slice selection index '\[3:0\]' outside data type's '\[2:0\]'
 %Error: t/t_mem_slice_bad.v:\d+: Slice selection index '\[3:0\]' outside data type's '\[1:0\]'
diff --git a/test_regress/t/t_mem_slice_conc_bad.pl b/test_regress/t/t_mem_slice_conc_bad.pl
index 7e422e2df..9b64617a5 100755
--- a/test_regress/t/t_mem_slice_conc_bad.pl
+++ b/test_regress/t/t_mem_slice_conc_bad.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mem_slice_dtype_bad.pl b/test_regress/t/t_mem_slice_dtype_bad.pl
index 585a256ef..2c72e1d70 100755
--- a/test_regress/t/t_mem_slice_dtype_bad.pl
+++ b/test_regress/t/t_mem_slice_dtype_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    fails=>1,
-    expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 '%Error: t/t_mem_slice_dtype_bad.v:\d+: ADD unexpected in assignment to unpacked array
 .*%Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_mem_slot.pl b/test_regress/t/t_mem_slot.pl
index e1e378296..da60e8024 100755
--- a/test_regress/t/t_mem_slot.pl
+++ b/test_regress/t/t_mem_slot.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mem_twoedge.pl b/test_regress/t/t_mem_twoedge.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_mem_twoedge.pl
+++ b/test_regress/t/t_mem_twoedge.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_metacmt_onoff.pl b/test_regress/t/t_metacmt_onoff.pl
index 46e0e7aba..89a5cd459 100755
--- a/test_regress/t/t_metacmt_onoff.pl
+++ b/test_regress/t/t_metacmt_onoff.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => [qw(--lint-only)],
-	 verilator_make_gcc => 0,
-	 make_top_shell => 0,
-	 make_main => 0,
-	 fails=>$Self->{vlt},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    verilator_flags2 => [qw(--lint-only)],
+    verilator_make_gcc => 0,
+    make_top_shell => 0,
+    make_main => 0,
+    fails => $Self->{vlt},
+    expect =>
 '%Warning-LITENDIAN: t/t_metacmt_onoff.v:\d+: Little bit endian vector: MSB < LSB of bit range: 0:1
 %Warning-LITENDIAN: Use "/\* verilator lint_off LITENDIAN \*/" and lint_on around source to disable this message.
 %Warning-LITENDIAN: t/t_metacmt_onoff.v:\d+: Little bit endian vector: MSB < LSB of bit range: 0:3
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mod_dup_bad.pl b/test_regress/t/t_mod_dup_bad.pl
index c08302fbc..1ebee5d1a 100755
--- a/test_regress/t/t_mod_dup_bad.pl
+++ b/test_regress/t/t_mod_dup_bad.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("Verilator only test") if !$Self->{vlt};
+scenarios(vlt_all => 1);
 
-compile (
-	 fails=>1,
-	 expect=>
+compile(
+    fails => 1,
+    expect =>
 '%Error-MODDUP: t/t_mod_dup_bad.v:\d+: Duplicate declaration of module: a
 %Error-MODDUP: t/t_mod_dup_bad.v:\d+: ... Location of original declaration
 .*
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mod_dup_ign.pl b/test_regress/t/t_mod_dup_ign.pl
index 09e214c4a..cb7f7d6fe 100755
--- a/test_regress/t/t_mod_dup_ign.pl
+++ b/test_regress/t/t_mod_dup_ign.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("Verilator only test") if !$Self->{vlt};
+scenarios(vlt_all => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 v_flags2 => ["--lint-only"],
-	 verilator_make_gcc => 0,
-	 );
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    v_flags2 => ["--lint-only"],
+    verilator_make_gcc => 0,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_mod_interface_array.pl b/test_regress/t/t_mod_interface_array.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_mod_interface_array.pl
+++ b/test_regress/t/t_mod_interface_array.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mod_interface_array1.pl b/test_regress/t/t_mod_interface_array1.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_mod_interface_array1.pl
+++ b/test_regress/t/t_mod_interface_array1.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mod_interface_array1_noinl.pl b/test_regress/t/t_mod_interface_array1_noinl.pl
index b58224421..a08606902 100755
--- a/test_regress/t/t_mod_interface_array1_noinl.pl
+++ b/test_regress/t/t_mod_interface_array1_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_mod_interface_array1.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mod_interface_array2.pl b/test_regress/t/t_mod_interface_array2.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_mod_interface_array2.pl
+++ b/test_regress/t/t_mod_interface_array2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mod_interface_array2_noinl.pl b/test_regress/t/t_mod_interface_array2_noinl.pl
index 9d3ea52cc..588fdf3fb 100755
--- a/test_regress/t/t_mod_interface_array2_noinl.pl
+++ b/test_regress/t/t_mod_interface_array2_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_mod_interface_array2.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mod_interface_array_noinl.pl b/test_regress/t/t_mod_interface_array_noinl.pl
index 1147f25f2..e4adc68ac 100755
--- a/test_regress/t/t_mod_interface_array_noinl.pl
+++ b/test_regress/t/t_mod_interface_array_noinl.pl
@@ -6,14 +6,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
+
+scenarios(simulator => 1);
+
 top_filename("t/t_mod_interface_array.v");
 
-compile (
+compile(
     v_flags2 => ["-Oi"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mod_longname.pl b/test_regress/t/t_mod_longname.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_mod_longname.pl
+++ b/test_regress/t/t_mod_longname.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mod_recurse.pl b/test_regress/t/t_mod_recurse.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_mod_recurse.pl
+++ b/test_regress/t/t_mod_recurse.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_mod_recurse1.pl b/test_regress/t/t_mod_recurse1.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_mod_recurse1.pl
+++ b/test_regress/t/t_mod_recurse1.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_optm_if_array.pl b/test_regress/t/t_optm_if_array.pl
index c39ed396f..37ce368a9 100755
--- a/test_regress/t/t_optm_if_array.pl
+++ b/test_regress/t/t_optm_if_array.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
-file_grep_not ("$Self->{obj_dir}/$Self->{VM_PREFIX}.cpp", qr/rstn_r/);
+file_grep_not("$Self->{obj_dir}/$Self->{VM_PREFIX}.cpp", qr/rstn_r/);
 
 ok(1);
 1;
diff --git a/test_regress/t/t_optm_redor.pl b/test_regress/t/t_optm_redor.pl
index c39ed396f..37ce368a9 100755
--- a/test_regress/t/t_optm_redor.pl
+++ b/test_regress/t/t_optm_redor.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
-file_grep_not ("$Self->{obj_dir}/$Self->{VM_PREFIX}.cpp", qr/rstn_r/);
+file_grep_not("$Self->{obj_dir}/$Self->{VM_PREFIX}.cpp", qr/rstn_r/);
 
 ok(1);
 1;
diff --git a/test_regress/t/t_order.pl b/test_regress/t/t_order.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_order.pl
+++ b/test_regress/t/t_order.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_order_2d.pl b/test_regress/t/t_order_2d.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_order_2d.pl
+++ b/test_regress/t/t_order_2d.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_order_clkinst.pl b/test_regress/t/t_order_clkinst.pl
index f6d3de4c4..11b8aeb6b 100755
--- a/test_regress/t/t_order_clkinst.pl
+++ b/test_regress/t/t_order_clkinst.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-my $fail = ($Self->{v3} && verilator_version() !~ /\(ord\)/);
+scenarios(simulator => 1);
 
-compile (
-	 );
+my $fail = ($Self->{vlt} && verilator_version() !~ /\(ord\)/);
 
-execute (
-	 check_finished => !$fail,
-	 fails => $fail,
-	 );
+compile(
+    );
+
+execute(
+    check_finished => !$fail,
+    fails => $fail,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_order_clkinst_bad.pl b/test_regress/t/t_order_clkinst_bad.pl
index caf2f84ba..51f214681 100755
--- a/test_regress/t/t_order_clkinst_bad.pl
+++ b/test_regress/t/t_order_clkinst_bad.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_order_clkinst.v");
 
-compile (
+compile(
     v_flags2 => ["-Wwarn-IMPERFECTSCH"],
-    fails=>1,
-    expect=>
+    fails => 1,
+    expect =>
 q{.*%Warning-IMPERFECTSCH: .*
 .*%Error: Exiting due to.*},
     );
diff --git a/test_regress/t/t_order_comboclkloop.pl b/test_regress/t/t_order_comboclkloop.pl
index 6254d1470..1be18a66c 100755
--- a/test_regress/t/t_order_comboclkloop.pl
+++ b/test_regress/t/t_order_comboclkloop.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished => 1,
-	 );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_order_comboloop.pl b/test_regress/t/t_order_comboloop.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_order_comboloop.pl
+++ b/test_regress/t/t_order_comboloop.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_order_doubleloop.pl b/test_regress/t/t_order_doubleloop.pl
index f6d3de4c4..11b8aeb6b 100755
--- a/test_regress/t/t_order_doubleloop.pl
+++ b/test_regress/t/t_order_doubleloop.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-my $fail = ($Self->{v3} && verilator_version() !~ /\(ord\)/);
+scenarios(simulator => 1);
 
-compile (
-	 );
+my $fail = ($Self->{vlt} && verilator_version() !~ /\(ord\)/);
 
-execute (
-	 check_finished => !$fail,
-	 fails => $fail,
-	 );
+compile(
+    );
+
+execute(
+    check_finished => !$fail,
+    fails => $fail,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_order_first.pl b/test_regress/t/t_order_first.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_order_first.pl
+++ b/test_regress/t/t_order_first.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_order_loop_bad.pl b/test_regress/t/t_order_loop_bad.pl
index 1275a65f0..a29a29006 100755
--- a/test_regress/t/t_order_loop_bad.pl
+++ b/test_regress/t/t_order_loop_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Error: Circular logic when ordering code .*
 %Error:      Example path: t/t_order_loop_bad.v:\d+:  ALWAYS
 %Error:      Example path: t/t_order_loop_bad.v:\d+:  t.ready
diff --git a/test_regress/t/t_order_multialways.pl b/test_regress/t/t_order_multialways.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_order_multialways.pl
+++ b/test_regress/t/t_order_multialways.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_order_multidriven.cpp b/test_regress/t/t_order_multidriven.cpp
index 86068112d..7fae07638 100644
--- a/test_regress/t/t_order_multidriven.cpp
+++ b/test_regress/t/t_order_multidriven.cpp
@@ -5,6 +5,9 @@
 #include "verilated.h"
 #include "verilated_vcd_c.h"
 
+#define STRINGIFY(x) STRINGIFY2(x)
+#define STRINGIFY2(x) #x
+
 Vt_order_multidriven *                  vcore;
 VerilatedVcdC *         vcd;
 vluint64_t                vtime;
@@ -43,7 +46,7 @@ int main() {
     vcd     = new VerilatedVcdC;
 
     vcore->trace( vcd, 99 );
-    vcd->open( "obj_dir/t_order_multidriven/sim.vcd" );
+    vcd->open(STRINGIFY(TEST_OBJ_DIR) "/simx.vcd" );
 
     vcore->i_clk_wr     = 0;
     vcore->i_clk_rd     = 0;
diff --git a/test_regress/t/t_order_multidriven.pl b/test_regress/t/t_order_multidriven.pl
index 1edafb042..7881a8cb4 100755
--- a/test_regress/t/t_order_multidriven.pl
+++ b/test_regress/t/t_order_multidriven.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     v_flags2 => ["--trace --exe $Self->{t_dir}/t_order_multidriven.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_order_quad.pl b/test_regress/t/t_order_quad.pl
index 653add643..66b07eadf 100755
--- a/test_regress/t/t_order_quad.pl
+++ b/test_regress/t/t_order_quad.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     make_top_shell => 0,
     make_main => 0,
     verilator_flags2 => ["--exe","$Self->{t_dir}/$Self->{name}.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_order_wireloop.pl b/test_regress/t/t_order_wireloop.pl
index 7a3675a5c..964e674f5 100755
--- a/test_regress/t/t_order_wireloop.pl
+++ b/test_regress/t/t_order_wireloop.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-    fails=>$Self->{v3},
+scenarios(simulator => 1);
+
+compile(
+    fails => $Self->{vlt},
     # Used to be %Error: t/t_order_wireloop.v:\d+: Wire inputs its own output, creating circular logic .wire x=x.
     # However we no longer gate optimize this
-	 expect=>
+    expect =>
 '%Warning-UNOPT: t/t_order_wireloop.v:\d+: Signal unoptimizable: Feedback to public clock or circular logic: bar
 ',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_package.pl b/test_regress/t/t_package.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_package.pl
+++ b/test_regress/t/t_package.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_package_abs.pl b/test_regress/t/t_package_abs.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_package_abs.pl
+++ b/test_regress/t/t_package_abs.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_package_ddecl.pl b/test_regress/t/t_package_ddecl.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_package_ddecl.pl
+++ b/test_regress/t/t_package_ddecl.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_package_dimport.pl b/test_regress/t/t_package_dimport.pl
index 6995cc39a..bff7cfb29 100755
--- a/test_regress/t/t_package_dimport.pl
+++ b/test_regress/t/t_package_dimport.pl
@@ -7,8 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
+
+compile(
+    );
 
 # Compile only
 
diff --git a/test_regress/t/t_package_dot.pl b/test_regress/t/t_package_dot.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_package_dot.pl
+++ b/test_regress/t/t_package_dot.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_package_enum.pl b/test_regress/t/t_package_enum.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_package_enum.pl
+++ b/test_regress/t/t_package_enum.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_package_export.pl b/test_regress/t/t_package_export.pl
index 27a0ad8e8..939096741 100755
--- a/test_regress/t/t_package_export.pl
+++ b/test_regress/t/t_package_export.pl
@@ -7,14 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vcs} and $Self->unsupported("VCS unsupported");
+scenarios(simulator => 1);
+$Self->{vcs} and unsupported("VCS unsupported");
 
-compile (
+compile(
     v_flags2 => ['+define+T_PACKAGE_EXPORT',],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_package_export_bad.pl b/test_regress/t/t_package_export_bad.pl
index 96f501b7e..d34ace777 100755
--- a/test_regress/t/t_package_export_bad.pl
+++ b/test_regress/t/t_package_export_bad.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_package_export.v");
 
-compile (
+compile(
     v_flags2 => ['+define+T_PACKAGE_EXPORT_BAD',],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Error: t/t_package_export.v:\d+: Can\'t find definition of scope/variable: PARAM2
 %Error: t/t_package_export.v:\d+: Can\'t find definition of scope/variable: PARAM3
 %Error: t/t_package_export.v:\d+: Can\'t find definition of scope/variable: PARAM2
diff --git a/test_regress/t/t_package_param.pl b/test_regress/t/t_package_param.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_package_param.pl
+++ b/test_regress/t/t_package_param.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_package_twodeep.pl b/test_regress/t/t_package_twodeep.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_package_twodeep.pl
+++ b/test_regress/t/t_package_twodeep.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_package_verb.pl b/test_regress/t/t_package_verb.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_package_verb.pl
+++ b/test_regress/t/t_package_verb.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param.pl b/test_regress/t/t_param.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_param.pl
+++ b/test_regress/t/t_param.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_array.pl b/test_regress/t/t_param_array.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_array.pl
+++ b/test_regress/t/t_param_array.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_array2.pl b/test_regress/t/t_param_array2.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_array2.pl
+++ b/test_regress/t/t_param_array2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_avec.pl b/test_regress/t/t_param_avec.pl
index 18bb867d4..39fa482ec 100755
--- a/test_regress/t/t_param_avec.pl
+++ b/test_regress/t/t_param_avec.pl
@@ -7,13 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, bug477");
+scenarios(simulator => 1);
+$Self->{vlt} and unsupported("Verilator unsupported, bug477");
 
-compile (
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_bit_sel.pl b/test_regress/t/t_param_bit_sel.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_bit_sel.pl
+++ b/test_regress/t/t_param_bit_sel.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_ceil.pl b/test_regress/t/t_param_ceil.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_param_ceil.pl
+++ b/test_regress/t/t_param_ceil.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_chain.pl b/test_regress/t/t_param_chain.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_chain.pl
+++ b/test_regress/t/t_param_chain.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_circ_bad.pl b/test_regress/t/t_param_circ_bad.pl
index 9b52eb1bd..c0997311d 100755
--- a/test_regress/t/t_param_circ_bad.pl
+++ b/test_regress/t/t_param_circ_bad.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Error: t/t_param_circ_bad.v:\d+: Variable\'s initial value is circular: X
 %Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_param_concat.pl b/test_regress/t/t_param_concat.pl
index 22a95a8dc..f018b8d24 100755
--- a/test_regress/t/t_param_concat.pl
+++ b/test_regress/t/t_param_concat.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ["--Wno-WIDTHCONCAT"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    verilator_flags2 => ["--Wno-WIDTHCONCAT"],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_concat_bad.pl b/test_regress/t/t_param_concat_bad.pl
index 20ca444fe..27e7256ad 100755
--- a/test_regress/t/t_param_concat_bad.pl
+++ b/test_regress/t/t_param_concat_bad.pl
@@ -7,16 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_param_concat.v");
 
-compile (
-	 fails=>1,
-	 expect=>
+compile(
+    fails => 1,
+    expect =>
 '%Warning-WIDTHCONCAT: t/t_param_concat.v:\d+: Unsized numbers/parameters not allowed in concatenations.
 %Warning-WIDTHCONCAT: Use "/\* verilator lint_off WIDTHCONCAT \*/" and lint_on around source to disable this message.
 %Warning-WIDTHCONCAT: t/t_param_concat.v:\d+: Unsized numbers/parameters not allowed in replications.
 .*%Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_const_part.pl b/test_regress/t/t_param_const_part.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_const_part.pl
+++ b/test_regress/t/t_param_const_part.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_ddeep_width.pl b/test_regress/t/t_param_ddeep_width.pl
index 87815646d..a6554ba87 100755
--- a/test_regress/t/t_param_ddeep_width.pl
+++ b/test_regress/t/t_param_ddeep_width.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_param_default.pl b/test_regress/t/t_param_default.pl
old mode 100644
new mode 100755
index 134a79f9e..990186320
--- a/test_regress/t/t_param_default.pl
+++ b/test_regress/t/t_param_default.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
      );
 
-execute (
-     check_finished=>1,
+execute(
+     check_finished => 1,
      );
 
 ok(1);
diff --git a/test_regress/t/t_param_default_bad.pl b/test_regress/t/t_param_default_bad.pl
index 2b22d5559..0d35c2868 100755
--- a/test_regress/t/t_param_default_bad.pl
+++ b/test_regress/t/t_param_default_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-     fails=>1,
-     expect=>
+scenarios(simulator => 1);
+
+compile(
+     fails => 1,
+     expect =>
 '%Error: Internal Error: t/t_param_default_bad.v:6: ../V3Param.cpp:\d+: Parameter without initial value
 %Error: Internal Error: See the manual and http://www.veripool.org/verilator for more assistance.
 .*%Error: Command Failed.*',
diff --git a/test_regress/t/t_param_first.pl b/test_regress/t/t_param_first.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_first.pl
+++ b/test_regress/t/t_param_first.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_func.pl b/test_regress/t/t_param_func.pl
index 385b6a57e..5c448de7c 100755
--- a/test_regress/t/t_param_func.pl
+++ b/test_regress/t/t_param_func.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_if_blk.pl b/test_regress/t/t_param_if_blk.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_if_blk.pl
+++ b/test_regress/t/t_param_if_blk.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_local.pl b/test_regress/t/t_param_local.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_local.pl
+++ b/test_regress/t/t_param_local.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_long.pl b/test_regress/t/t_param_long.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_param_long.pl
+++ b/test_regress/t/t_param_long.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_mem_attr.pl b/test_regress/t/t_param_mem_attr.pl
index ba0e9879b..3a7763b0d 100755
--- a/test_regress/t/t_param_mem_attr.pl
+++ b/test_regress/t/t_param_mem_attr.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # Compile only test.
-compile (
-	 );
+compile(
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_module.pl b/test_regress/t/t_param_module.pl
index 38eec757b..39c42f7d0 100755
--- a/test_regress/t/t_param_module.pl
+++ b/test_regress/t/t_param_module.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # Compile only test
-compile (
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_named.pl b/test_regress/t/t_param_named.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_param_named.pl
+++ b/test_regress/t/t_param_named.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_named_2.pl b/test_regress/t/t_param_named_2.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_param_named_2.pl
+++ b/test_regress/t/t_param_named_2.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_no_parentheses.pl b/test_regress/t/t_param_no_parentheses.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_param_no_parentheses.pl
+++ b/test_regress/t/t_param_no_parentheses.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_package.pl b/test_regress/t/t_param_package.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_package.pl
+++ b/test_regress/t/t_param_package.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_public.pl b/test_regress/t/t_param_public.pl
index 4408cbf72..0560d989d 100755
--- a/test_regress/t/t_param_public.pl
+++ b/test_regress/t/t_param_public.pl
@@ -7,19 +7,21 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 if ($Self->{vlt}) {
-    compile (
-	verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
-	make_top_shell => 0,
-	make_main => 0,
-	);
+    compile(
+        verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
+        make_top_shell => 0,
+        make_main => 0,
+        );
 } else {
-    compile (
-	);
+    compile(
+        );
 }
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_real.pl b/test_regress/t/t_param_real.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_real.pl
+++ b/test_regress/t/t_param_real.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_repl.pl b/test_regress/t/t_param_repl.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_param_repl.pl
+++ b/test_regress/t/t_param_repl.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_seg.pl b/test_regress/t/t_param_seg.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_seg.pl
+++ b/test_regress/t/t_param_seg.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_sel.pl b/test_regress/t/t_param_sel.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_param_sel.pl
+++ b/test_regress/t/t_param_sel.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_sel_range.pl b/test_regress/t/t_param_sel_range.pl
index dec6d69ed..d3139fae5 100755
--- a/test_regress/t/t_param_sel_range.pl
+++ b/test_regress/t/t_param_sel_range.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only -Wno-SELRANGE"],
-    fails=>0,
+    fails => 0,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_param_sel_range_bad.pl b/test_regress/t/t_param_sel_range_bad.pl
index da3334ee2..0e1114afa 100755
--- a/test_regress/t/t_param_sel_range_bad.pl
+++ b/test_regress/t/t_param_sel_range_bad.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_param_sel_range.v");
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>1,
+    fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Warning-SELRANGE: t/t_param_sel_range.v:\d+: Selection index out of range: 7:7 outside 4:0
 %Warning-SELRANGE: Use .* to disable this message.
 %Error: Exiting due to.*',
diff --git a/test_regress/t/t_param_shift.pl b/test_regress/t/t_param_shift.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_shift.pl
+++ b/test_regress/t/t_param_shift.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_type.pl b/test_regress/t/t_param_type.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_type.pl
+++ b/test_regress/t/t_param_type.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_type2.pl b/test_regress/t/t_param_type2.pl
index ab1195fb5..73dc10324 100755
--- a/test_regress/t/t_param_type2.pl
+++ b/test_regress/t/t_param_type2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-#execute (
-#    check_finished=>1,
+#execute(
+#    check_finished => 1,
 #    );
 
 ok(1);
diff --git a/test_regress/t/t_param_up_bad.pl b/test_regress/t/t_param_up_bad.pl
index 17f2bb4c2..4dde9334b 100755
--- a/test_regress/t/t_param_up_bad.pl
+++ b/test_regress/t/t_param_up_bad.pl
@@ -7,14 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-compile (
+scenarios(vlt_all => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
     fails => 1,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
-    expect=>
+    expect =>
 '%Error: t/t_param_up_bad.v:\d+: Can\'t find definition of scope/variable: bar
 .*%Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_param_value.pl b/test_regress/t/t_param_value.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_param_value.pl
+++ b/test_regress/t/t_param_value.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_param_while.pl b/test_regress/t/t_param_while.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_param_while.pl
+++ b/test_regress/t/t_param_while.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_param_wide_io.pl b/test_regress/t/t_param_wide_io.pl
index b12dfcc0c..fc7eccce3 100755
--- a/test_regress/t/t_param_wide_io.pl
+++ b/test_regress/t/t_param_wide_io.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-#execute ();
+#execute();
 
 ok(1);
 1;
diff --git a/test_regress/t/t_parse_delay.pl b/test_regress/t/t_parse_delay.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_parse_delay.pl
+++ b/test_regress/t/t_parse_delay.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_pipe_exit_bad.pl b/test_regress/t/t_pipe_exit_bad.pl
index 4cbba3f9d..c190c3dd7 100755
--- a/test_regress/t/t_pipe_exit_bad.pl
+++ b/test_regress/t/t_pipe_exit_bad.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("Verilator only test") if !$Self->{vlt};
+scenarios(vlt => 1);
 
 top_filename("t/t_pipe_filter.v");
 
-compile (
+compile(
     verilator_flags2 => ['-E --pipe-filter \'perl t/t_pipe_exit_bad.pf\' '],
-    verilator_make_gcc=>0,
+    verilator_make_gcc => 0,
     stdout_filename => $stdout_filename,
-    fails=>1,
-    expect=>
+    fails => 1,
+    expect =>
 '%Error: t_pipe_exit_bad.pf: Intentional bad exit status....*',
     );
 ok(1);
diff --git a/test_regress/t/t_pipe_filter.pl b/test_regress/t/t_pipe_filter.pl
index 08a228650..e33936e57 100755
--- a/test_regress/t/t_pipe_filter.pl
+++ b/test_regress/t/t_pipe_filter.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("Verilator only test") if !$Self->{vlt};
+scenarios(vlt => 1);
 
 $Self->{golden_out} ||= "t/$Self->{name}.out";
 my $stdout_filename = "$Self->{obj_dir}/$Self->{name}__test.vpp";
 
-compile (
+compile(
     verilator_flags2 => ['-E --pipe-filter \'perl t/t_pipe_filter.pf\' '],
-    verilator_make_gcc=>0,
+    verilator_make_gcc => 0,
     stdout_filename => $stdout_filename,
     );
 ok(files_identical($stdout_filename, $Self->{golden_out}));
diff --git a/test_regress/t/t_pp_circdef_bad.pl b/test_regress/t/t_pp_circdef_bad.pl
index 31fc36b26..28672314c 100755
--- a/test_regress/t/t_pp_circdef_bad.pl
+++ b/test_regress/t/t_pp_circdef_bad.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Error: t/t_pp_circdef_bad.v:\d+: Recursive `define or other nested inclusion
 .*
 %Error: Exiting due to.*',
diff --git a/test_regress/t/t_pp_display.pl b/test_regress/t/t_pp_display.pl
index ffa68590b..77c3ca8a0 100755
--- a/test_regress/t/t_pp_display.pl
+++ b/test_regress/t/t_pp_display.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(vlt => 1);
 
-execute (
-	 check_finished=>1,
-	 expect=>quotemeta(
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    expect => quotemeta(
 qq{pre thrupre thrumid thrupost post: "right side"
 left side: "right side"
 left side: "right side"
diff --git a/test_regress/t/t_pp_dupdef.pl b/test_regress/t/t_pp_dupdef.pl
index a659ac037..b9555f527 100755
--- a/test_regress/t/t_pp_dupdef.pl
+++ b/test_regress/t/t_pp_dupdef.pl
@@ -7,9 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
+compile(
     verilator_flags2 => ["-Wno-REDEFMACRO"],
     );
 
diff --git a/test_regress/t/t_pp_dupdef_bad.pl b/test_regress/t/t_pp_dupdef_bad.pl
index 5b9766fd1..91f18972a 100755
--- a/test_regress/t/t_pp_dupdef_bad.pl
+++ b/test_regress/t/t_pp_dupdef_bad.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt => 1);
+
 top_filename("t/t_pp_dupdef.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Warning-REDEFMACRO: t/t_pp_dupdef.v:\d+: Redefining existing define: DUP, with different value: barney
 %Warning-REDEFMACRO: Use .* to disable this message.
 %Warning-REDEFMACRO: t/t_pp_dupdef.v:\d+: Previous definition is here, with value: fred
diff --git a/test_regress/t/t_pp_lib.pl b/test_regress/t/t_pp_lib.pl
index 8c36e6f68..9d820dc30 100755
--- a/test_regress/t/t_pp_lib.pl
+++ b/test_regress/t/t_pp_lib.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ['-v', 't/t_pp_lib_library.v'],
-	 );
+scenarios(vlt => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    v_flags2 => ['-v', 't/t_pp_lib_library.v'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_pp_misdef_bad.pl b/test_regress/t/t_pp_misdef_bad.pl
index 0fb0f0c1c..1b89ea0fe 100755
--- a/test_regress/t/t_pp_misdef_bad.pl
+++ b/test_regress/t/t_pp_misdef_bad.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Error: t/t_pp_misdef_bad.v:\d+: Define or directive not defined: `NOTDEF
 %Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_pp_pragmas.pl b/test_regress/t/t_pp_pragmas.pl
index 7058e622f..beafec13a 100755
--- a/test_regress/t/t_pp_pragmas.pl
+++ b/test_regress/t/t_pp_pragmas.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(vlt => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_pp_underline_bad.pl b/test_regress/t/t_pp_underline_bad.pl
index 863ab4c5c..795815f25 100755
--- a/test_regress/t/t_pp_underline_bad.pl
+++ b/test_regress/t/t_pp_underline_bad.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
-	 verilator_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+compile(
+    verilator_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Error: t/t_pp_underline_bad.v:\d+: Extra underscore in meta-comment.*
 %Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_preproc.pl b/test_regress/t/t_preproc.pl
index d4c1efdc3..f2c515d08 100755
--- a/test_regress/t/t_preproc.pl
+++ b/test_regress/t/t_preproc.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
 $Self->{golden_out} ||= "t/$Self->{name}.out";
 my $stdout_filename = "$Self->{obj_dir}/$Self->{name}__test.vpp";
 
-compile (
+compile(
     verilator_flags2 => ['-DDEF_A0 -DPREDEF_COMMAND_LINE -E'],
-    verilator_make_gcc=>0,
+    verilator_make_gcc => 0,
     stdout_filename => $stdout_filename,
     );
 
@@ -46,14 +46,14 @@ sub preproc_check {
 	    if ($line =~ /^Line_Preproc_Check\s+(\d+)/) {
 		my $linecmt = $1;
 		my $check = shift @Line_Checks;
-		if (!$check) { $Self->error("$filename2:$.: Extra Line_Preproc_Check\n"); }
-		if ($linecmt != $check) { $Self->error("$filename2:$.: __LINE__ inserted $linecmt, exp=$check\n"); }
-		if ($lineno != $check)  { $Self->error("$filename2:$.: __LINE__ on `line $lineno, exp=$check\n"); }
+                if (!$check) { error("$filename2:$.: Extra Line_Preproc_Check\n"); }
+                if ($linecmt != $check) { error("$filename2:$.: __LINE__ inserted $linecmt, exp=$check\n"); }
+                if ($lineno != $check)  { error("$filename2:$.: __LINE__ on `line $lineno, exp=$check\n"); }
 	    }
 	}
 	$fh->close;
     }
-    if ($Line_Checks[0]) { $Self->error("$filename2: Missing a Line_Preproc_Check\n"); }
+    if ($Line_Checks[0]) { error("$filename2: Missing a Line_Preproc_Check\n"); }
     return 1;
 }
 
diff --git a/test_regress/t/t_preproc_def09.pl b/test_regress/t/t_preproc_def09.pl
index 606b72845..a44da8bdb 100755
--- a/test_regress/t/t_preproc_def09.pl
+++ b/test_regress/t/t_preproc_def09.pl
@@ -7,13 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
 my $stdout_filename = "$Self->{obj_dir}/$Self->{name}__test.vpp";
 
-compile (
+compile(
     verilator_flags2 => ['-E'],
-    verilator_make_gcc=>0,
+    verilator_make_gcc => 0,
     stdout_filename => $stdout_filename,
     );
 
diff --git a/test_regress/t/t_preproc_dos.pl b/test_regress/t/t_preproc_dos.pl
index 04041384c..c43722876 100755
--- a/test_regress/t/t_preproc_dos.pl
+++ b/test_regress/t/t_preproc_dos.pl
@@ -7,6 +7,8 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("$Self->{obj_dir}/$Self->{name}.v");
 
 # Rather then having to maintain a new .v and .out, simply add returns
diff --git a/test_regress/t/t_preproc_ifdef.pl b/test_regress/t/t_preproc_ifdef.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_preproc_ifdef.pl
+++ b/test_regress/t/t_preproc_ifdef.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_preproc_inc_bad.pl b/test_regress/t/t_preproc_inc_bad.pl
index aa3d0eae9..70c332798 100755
--- a/test_regress/t/t_preproc_inc_bad.pl
+++ b/test_regress/t/t_preproc_inc_bad.pl
@@ -7,13 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
-compile (
-	 verilator_flags2 => ["--lint-only"],
-	 fails=>1,
+compile(
+    verilator_flags2 => ["--lint-only"],
+    fails => 1,
     # The .vh file has the error, not the .v file
-	 expect=>
+    expect =>
 '%Error: t/t_preproc_inc_inc_bad.vh:10: syntax error, unexpected endmodule, expecting IDENTIFIER'
     );
 
diff --git a/test_regress/t/t_preproc_kwd.pl b/test_regress/t/t_preproc_kwd.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_preproc_kwd.pl
+++ b/test_regress/t/t_preproc_kwd.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_preproc_noline.pl b/test_regress/t/t_preproc_noline.pl
index 0bb99340a..6f878a40c 100755
--- a/test_regress/t/t_preproc_noline.pl
+++ b/test_regress/t/t_preproc_noline.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
 my $stdout_filename = "$Self->{obj_dir}/$Self->{name}__test.vpp";
 
 top_filename("t/t_preproc_noline.v");
 
-compile (
+compile(
     verilator_flags2 => ['-E -P'],
-    verilator_make_gcc=>0,
+    verilator_make_gcc => 0,
     stdout_filename => $stdout_filename,
     );
 
diff --git a/test_regress/t/t_preproc_persist.pl b/test_regress/t/t_preproc_persist.pl
index 87fc25f66..bdb83fc1e 100755
--- a/test_regress/t/t_preproc_persist.pl
+++ b/test_regress/t/t_preproc_persist.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
 my $stdout_filename = "$Self->{obj_dir}/$Self->{name}__test.vpp";
 
-compile (
+compile(
     # Override default flags
     v_flags => [''],
     v_other_filenames => ["t_preproc_persist2.v"],
diff --git a/test_regress/t/t_preproc_ttempty.pl b/test_regress/t/t_preproc_ttempty.pl
index c76f0a87a..c17481020 100755
--- a/test_regress/t/t_preproc_ttempty.pl
+++ b/test_regress/t/t_preproc_ttempty.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
 my $stdout_filename = "$Self->{obj_dir}/$Self->{name}__test.vpp";
 
-compile (
+compile(
     # Override default flags
     v_flags => [''],
     verilator_flags => ["-E -P +incdir+t -Mdir $Self->{obj_dir}", ],
diff --git a/test_regress/t/t_preproc_undefineall.pl b/test_regress/t/t_preproc_undefineall.pl
index 9324c83cb..51080a82b 100755
--- a/test_regress/t/t_preproc_undefineall.pl
+++ b/test_regress/t/t_preproc_undefineall.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ['+define+PREDEF_COMMAND_LINE'],
     verilator_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
diff --git a/test_regress/t/t_program.pl b/test_regress/t/t_program.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_program.pl
+++ b/test_regress/t/t_program.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_repeat.pl b/test_regress/t/t_repeat.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_repeat.pl
+++ b/test_regress/t/t_repeat.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_rnd.pl b/test_regress/t/t_rnd.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_rnd.pl
+++ b/test_regress/t/t_rnd.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_savable.pl b/test_regress/t/t_savable.pl
index f74dcf0fd..942feae4d 100755
--- a/test_regress/t/t_savable.pl
+++ b/test_regress/t/t_savable.pl
@@ -7,21 +7,23 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--savable"],
     save_time => 500,
     );
 
-execute (
-    check_finished=>0,
+execute(
+    check_finished => 0,
     all_run_flags => ['+save_time=500'],
     );
 
--r "$Self->{obj_dir}/saved.vltsv" or $Self->error("Saved.vltsv not created\n");
+-r "$Self->{obj_dir}/saved.vltsv" or error("Saved.vltsv not created\n");
 
-execute (
+execute(
     all_run_flags => ['+save_restore=1'],
-    check_finished=>1,
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_scope_map.cpp b/test_regress/t/t_scope_map.cpp
index 4c8ebdd20..9b7863f0c 100644
--- a/test_regress/t/t_scope_map.cpp
+++ b/test_regress/t/t_scope_map.cpp
@@ -13,6 +13,9 @@
 
 #include "Vt_scope_map.h"
 
+#define STRINGIFY(x) STRINGIFY2(x)
+#define STRINGIFY2(x) #x
+
 using namespace std;
 
 unsigned long long main_time = 0;
@@ -30,7 +33,7 @@ int main(int argc, char **argv, char **env) {
 
     VerilatedVcdC* tfp = new VerilatedVcdC;
     top->trace(tfp,99);
-    tfp->open("obj_dir/t_scope_map/simx.vcd");
+    tfp->open(STRINGIFY(TEST_OBJ_DIR) "/simx.vcd");
 
     top->CLK = 0;
     top->eval();
diff --git a/test_regress/t/t_scope_map.pl b/test_regress/t/t_scope_map.pl
index d3e6e19b0..e93d68454 100755
--- a/test_regress/t/t_scope_map.pl
+++ b/test_regress/t/t_scope_map.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     v_flags2 => ["--trace --exe $Self->{t_dir}/$Self->{name}.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_select_bad_msb.pl b/test_regress/t/t_select_bad_msb.pl
index e81c0312e..8fe0627aa 100755
--- a/test_regress/t/t_select_bad_msb.pl
+++ b/test_regress/t/t_select_bad_msb.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 fails=>1,
-	 expect=>
+compile(
+    fails => 1,
+    expect =>
 '%Warning-LITENDIAN: t/t_select_bad_msb.v:\d+: Little bit endian vector: MSB < LSB of bit range: 0:22
 .*
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_bad_range.pl b/test_regress/t/t_select_bad_range.pl
index db2b0202e..9fcd9df23 100755
--- a/test_regress/t/t_select_bad_range.pl
+++ b/test_regress/t/t_select_bad_range.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 '%Warning-SELRANGE: t/t_select_bad_range.v:\d+: Selection index out of range: 44:44 outside 43:0
 %Warning-SELRANGE: Use .*
 %Warning-SELRANGE: t/t_select_bad_range.v:\d+: Selection index out of range: 44:41 outside 43:0
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_bad_range2.pl b/test_regress/t/t_select_bad_range2.pl
index f127f0494..9f7ddd7b2 100755
--- a/test_regress/t/t_select_bad_range2.pl
+++ b/test_regress/t/t_select_bad_range2.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 '%Warning-SELRANGE: t/t_select_bad_range2.v:\d+: Selection index out of range: 3:2 outside 1:0
 %Warning-SELRANGE: Use .*
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_bad_range3.pl b/test_regress/t/t_select_bad_range3.pl
index c7f200d12..9f8ee62e7 100755
--- a/test_regress/t/t_select_bad_range3.pl
+++ b/test_regress/t/t_select_bad_range3.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 '%Warning-SELRANGE: t/t_select_bad_range3.v:\d+: Selection index out of range: 13 outside 12:10
 %Warning-SELRANGE: Use .*
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_bad_tri.pl b/test_regress/t/t_select_bad_tri.pl
index 1dd2d0389..a6879d9cf 100755
--- a/test_regress/t/t_select_bad_tri.pl
+++ b/test_regress/t/t_select_bad_tri.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 q{%Error: t/t_select_bad_tri.v:\d+: Selection index is constantly unknown or tristated: lsb=7'bxxxxxxx width=32'sh47
 %Error: Exiting due to.*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_bound1.pl b/test_regress/t/t_select_bound1.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_select_bound1.pl
+++ b/test_regress/t/t_select_bound1.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_select_bound2.pl b/test_regress/t/t_select_bound2.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_select_bound2.pl
+++ b/test_regress/t/t_select_bound2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_select_index.pl b/test_regress/t/t_select_index.pl
index 98dc46682..c9adf6d32 100755
--- a/test_regress/t/t_select_index.pl
+++ b/test_regress/t/t_select_index.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_index2.pl b/test_regress/t/t_select_index2.pl
index 514f638f2..dd4decbdb 100755
--- a/test_regress/t/t_select_index2.pl
+++ b/test_regress/t/t_select_index2.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_select_lhs_oob.pl b/test_regress/t/t_select_lhs_oob.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_select_lhs_oob.pl
+++ b/test_regress/t/t_select_lhs_oob.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_select_lhs_oob2.pl b/test_regress/t/t_select_lhs_oob2.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_select_lhs_oob2.pl
+++ b/test_regress/t/t_select_lhs_oob2.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_little.pl b/test_regress/t/t_select_little.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_select_little.pl
+++ b/test_regress/t/t_select_little.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_little_pack.pl b/test_regress/t/t_select_little_pack.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_select_little_pack.pl
+++ b/test_regress/t/t_select_little_pack.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_loop.pl b/test_regress/t/t_select_loop.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_select_loop.pl
+++ b/test_regress/t/t_select_loop.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_negative.pl b/test_regress/t/t_select_negative.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_select_negative.pl
+++ b/test_regress/t/t_select_negative.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_param.pl b/test_regress/t/t_select_param.pl
index 98dc46682..c9adf6d32 100755
--- a/test_regress/t/t_select_param.pl
+++ b/test_regress/t/t_select_param.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_plus.pl b/test_regress/t/t_select_plus.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_select_plus.pl
+++ b/test_regress/t/t_select_plus.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_plusloop.pl b/test_regress/t/t_select_plusloop.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_select_plusloop.pl
+++ b/test_regress/t/t_select_plusloop.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_runtime_range.pl b/test_regress/t/t_select_runtime_range.pl
index 98dc46682..c9adf6d32 100755
--- a/test_regress/t/t_select_runtime_range.pl
+++ b/test_regress/t/t_select_runtime_range.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_select_set.pl b/test_regress/t/t_select_set.pl
index 98dc46682..c9adf6d32 100755
--- a/test_regress/t/t_select_set.pl
+++ b/test_regress/t/t_select_set.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_slice_cond.pl b/test_regress/t/t_slice_cond.pl
index 385b6a57e..5c448de7c 100755
--- a/test_regress/t/t_slice_cond.pl
+++ b/test_regress/t/t_slice_cond.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
 ok(1);
diff --git a/test_regress/t/t_slice_init.pl b/test_regress/t/t_slice_init.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_slice_init.pl
+++ b/test_regress/t/t_slice_init.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_slice_struct_array_modport.pl b/test_regress/t/t_slice_struct_array_modport.pl
index 086fa8d0c..62c359668 100755
--- a/test_regress/t/t_slice_struct_array_modport.pl
+++ b/test_regress/t/t_slice_struct_array_modport.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--lint-only"],
-    fails=>0,
+    fails => 0,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_static_elab.pl b/test_regress/t/t_static_elab.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_static_elab.pl
+++ b/test_regress/t/t_static_elab.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_stream.pl b/test_regress/t/t_stream.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_stream.pl
+++ b/test_regress/t/t_stream.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_stream2.pl b/test_regress/t/t_stream2.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_stream2.pl
+++ b/test_regress/t/t_stream2.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_stream3.pl b/test_regress/t/t_stream3.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_stream3.pl
+++ b/test_regress/t/t_stream3.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_string.pl b/test_regress/t/t_string.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_string.pl
+++ b/test_regress/t/t_string.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_string_type_methods.pl b/test_regress/t/t_string_type_methods.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_string_type_methods.pl
+++ b/test_regress/t/t_string_type_methods.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_struct_anon.pl b/test_regress/t/t_struct_anon.pl
index 1774aab4f..76bfa062d 100755
--- a/test_regress/t/t_struct_anon.pl
+++ b/test_regress/t/t_struct_anon.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_struct_array.pl b/test_regress/t/t_struct_array.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_struct_array.pl
+++ b/test_regress/t/t_struct_array.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_struct_init.pl b/test_regress/t/t_struct_init.pl
index 4f0058853..c9adf6d32 100755
--- a/test_regress/t/t_struct_init.pl
+++ b/test_regress/t/t_struct_init.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_struct_init_bad.pl b/test_regress/t/t_struct_init_bad.pl
index 4e56c027f..cb1856bf2 100755
--- a/test_regress/t/t_struct_init_bad.pl
+++ b/test_regress/t/t_struct_init_bad.pl
@@ -7,13 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_struct_init.v");
 
-
-compile (
+compile(
     v_flags2 => ['+define+T_STRUCT_INIT_BAD'],
     fails => 1,
-    expect=>
+    expect =>
 '%Error: t/t_struct_init.v:\d+: Assignment pattern contains duplicate entry: b1
 %Error: Exiting due to.*'
     );
diff --git a/test_regress/t/t_struct_init_trace.pl b/test_regress/t/t_struct_init_trace.pl
index d3c5875b3..972550651 100755
--- a/test_regress/t/t_struct_init_trace.pl
+++ b/test_regress/t/t_struct_init_trace.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_struct_init.v");
 
-compile (
-	 verilator_flags2 => ['--cc --trace'],
-	 );
+compile(
+    verilator_flags2 => ['--cc --trace'],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_struct_nest.pl b/test_regress/t/t_struct_nest.pl
index 1774aab4f..76bfa062d 100755
--- a/test_regress/t/t_struct_nest.pl
+++ b/test_regress/t/t_struct_nest.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
     verilator_make_gcc => 0,
     make_top_shell => 0,
diff --git a/test_regress/t/t_struct_notfound_bad.pl b/test_regress/t/t_struct_notfound_bad.pl
index 702415cb8..54190c119 100755
--- a/test_regress/t/t_struct_notfound_bad.pl
+++ b/test_regress/t/t_struct_notfound_bad.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 '%Error: t/t_struct_notfound_bad.v:\d+: Member \'nfmember\' not found in structure
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_struct_packed_sysfunct.pl b/test_regress/t/t_struct_packed_sysfunct.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_struct_packed_sysfunct.pl
+++ b/test_regress/t/t_struct_packed_sysfunct.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_struct_packed_value_list.pl b/test_regress/t/t_struct_packed_value_list.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_struct_packed_value_list.pl
+++ b/test_regress/t/t_struct_packed_value_list.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_struct_packed_write_read.pl b/test_regress/t/t_struct_packed_write_read.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_struct_packed_write_read.pl
+++ b/test_regress/t/t_struct_packed_write_read.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_struct_param.pl b/test_regress/t/t_struct_param.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_struct_param.pl
+++ b/test_regress/t/t_struct_param.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_struct_pat_width.pl b/test_regress/t/t_struct_pat_width.pl
index 4f0058853..c9adf6d32 100755
--- a/test_regress/t/t_struct_pat_width.pl
+++ b/test_regress/t/t_struct_pat_width.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_struct_port.pl b/test_regress/t/t_struct_port.pl
index 4f0058853..c9adf6d32 100755
--- a/test_regress/t/t_struct_port.pl
+++ b/test_regress/t/t_struct_port.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_struct_portsel.pl b/test_regress/t/t_struct_portsel.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_struct_portsel.pl
+++ b/test_regress/t/t_struct_portsel.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_struct_unaligned.pl b/test_regress/t/t_struct_unaligned.pl
index 3608a5acd..35849af98 100755
--- a/test_regress/t/t_struct_unaligned.pl
+++ b/test_regress/t/t_struct_unaligned.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # Note: need to run at a higher optimization level to reproduce the issue
 $Self->{benchmark} = 1;
 
-compile (
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_struct_unpacked.pl b/test_regress/t/t_struct_unpacked.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_struct_unpacked.pl
+++ b/test_regress/t/t_struct_unpacked.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_struct_unpacked_bad.pl b/test_regress/t/t_struct_unpacked_bad.pl
index 095c3500c..27d15d1fe 100755
--- a/test_regress/t/t_struct_unpacked_bad.pl
+++ b/test_regress/t/t_struct_unpacked_bad.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => $Self->{vlt},
+    expect =>
 q{%Warning-UNPACKED: t/t_struct_unpacked_bad.v:\d+: Unsupported: Unpacked struct/union
 %Warning-UNPACKED: Use .*
 .*%Error: Exiting due to.*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sv_bus_mux_demux.pl b/test_regress/t/t_sv_bus_mux_demux.pl
index 43179dd12..b1562d434 100755
--- a/test_regress/t/t_sv_bus_mux_demux.pl
+++ b/test_regress/t/t_sv_bus_mux_demux.pl
@@ -7,14 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, bug181");
+scenarios(simulator => 1);
+$Self->{vlt} and unsupported("Verilator unsupported, bug181");
 
-compile (
-	 );
+compile(
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sv_conditional.pl b/test_regress/t/t_sv_conditional.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_sv_conditional.pl
+++ b/test_regress/t/t_sv_conditional.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_sv_cpu.pl b/test_regress/t/t_sv_cpu.pl
index 2d864dc4a..4ffed6304 100755
--- a/test_regress/t/t_sv_cpu.pl
+++ b/test_regress/t/t_sv_cpu.pl
@@ -7,36 +7,38 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # 22-Mar-2012: Modifications for this test contributed by Jeremy Bennett,
 # Embecosm.
 
-compile (
+compile(
     # Taken from the original VCS command line.
     v_flags2 => ["t/t_sv_cpu_code/timescale.sv",
-		 "t/t_sv_cpu_code/program_h.sv",
-		 "t/t_sv_cpu_code/pads_h.sv",
-		 "t/t_sv_cpu_code/ports_h.sv",
-		 "t/t_sv_cpu_code/pinout_h.sv",
-		 "t/t_sv_cpu_code/genbus_if.sv",
-		 "t/t_sv_cpu_code/pads_if.sv",
-		 "t/t_sv_cpu_code/adrdec.sv",
-		 "t/t_sv_cpu_code/pad_gpio.sv",
-		 "t/t_sv_cpu_code/pad_vdd.sv",
-		 "t/t_sv_cpu_code/pad_gnd.sv",
-		 "t/t_sv_cpu_code/pads.sv",
-		 "t/t_sv_cpu_code/ports.sv",
-		 "t/t_sv_cpu_code/ac_dig.sv",
-		 "t/t_sv_cpu_code/ac_ana.sv",
-		 "t/t_sv_cpu_code/ac.sv",
-		 "t/t_sv_cpu_code/cpu.sv",
-		 "t/t_sv_cpu_code/chip.sv"],
+                 "t/t_sv_cpu_code/program_h.sv",
+                 "t/t_sv_cpu_code/pads_h.sv",
+                 "t/t_sv_cpu_code/ports_h.sv",
+                 "t/t_sv_cpu_code/pinout_h.sv",
+                 "t/t_sv_cpu_code/genbus_if.sv",
+                 "t/t_sv_cpu_code/pads_if.sv",
+                 "t/t_sv_cpu_code/adrdec.sv",
+                 "t/t_sv_cpu_code/pad_gpio.sv",
+                 "t/t_sv_cpu_code/pad_vdd.sv",
+                 "t/t_sv_cpu_code/pad_gnd.sv",
+                 "t/t_sv_cpu_code/pads.sv",
+                 "t/t_sv_cpu_code/ports.sv",
+                 "t/t_sv_cpu_code/ac_dig.sv",
+                 "t/t_sv_cpu_code/ac_ana.sv",
+                 "t/t_sv_cpu_code/ac.sv",
+                 "t/t_sv_cpu_code/cpu.sv",
+                 "t/t_sv_cpu_code/chip.sv"],
     vcs_flags2 => ["-R -sverilog +memcbk -y t/t_sv_cpu_code +libext+.sv+ +incdir+t/t_sv_cpu_code"],
     verilator_flags2 => ["-y t/t_sv_cpu_code +libext+.sv+ +incdir+t/t_sv_cpu_code --top-module t"],
     iv_flags2 => ["-yt/t_sv_cpu_code -It/t_sv_cpu_code -Y.sv"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
      );
 
 ok(1);
diff --git a/test_regress/t/t_sys_file_autoflush.pl b/test_regress/t/t_sys_file_autoflush.pl
index aeafbe7e3..db9de3301 100755
--- a/test_regress/t/t_sys_file_autoflush.pl
+++ b/test_regress/t/t_sys_file_autoflush.pl
@@ -7,17 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_sys_file_basic.v");
 
-compile (
-	 v_flags2 => ['+incdir+../include',
-		      '+define+AUTOFLUSH'],
-	 verilator_flags2 => ['--autoflush'],
-	 );
+compile(
+    v_flags2 => ['+incdir+../include',
+                 '+define+AUTOFLUSH'],
+    verilator_flags2 => ['--autoflush'],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sys_file_basic.pl b/test_regress/t/t_sys_file_basic.pl
index 2cc1da6ba..8d31206d5 100755
--- a/test_regress/t/t_sys_file_basic.pl
+++ b/test_regress/t/t_sys_file_basic.pl
@@ -7,20 +7,22 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 unlink("$Self->{obj_dir}/t_sys_file_basic_test.log");
 
-compile (
+compile(
     v_flags2 => ['+incdir+../include'],
     # Build without cached objects, see bug363
     verilator_flags2 => ["--exe ../$Self->{main_filename}"],
-    make_flags=>'MAKE_MAIN=0 VM_PARALLEL_BUILDS=0',
+    make_flags => 'MAKE_MAIN=0 VM_PARALLEL_BUILDS=0',
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
-file_grep ("$Self->{obj_dir}/t_sys_file_basic_test.log",
+file_grep("$Self->{obj_dir}/t_sys_file_basic_test.log",
 qr/\[0\] hello v=12345667
 \[0\] Hello2
 /);
diff --git a/test_regress/t/t_sys_file_basic.v b/test_regress/t/t_sys_file_basic.v
index 182e8fa27..13b477d95 100644
--- a/test_regress/t/t_sys_file_basic.v
+++ b/test_regress/t/t_sys_file_basic.v
@@ -5,6 +5,8 @@
 
 `include "verilated.v"
 
+`define STRINGIFY(x) `"x`"
+
 module t;
    `verilator_file_descriptor file;
 
@@ -36,10 +38,10 @@ module t;
 
 `ifdef AUTOFLUSH
       // The "w" is required so we get a FD not a MFD
-      file = $fopen("obj_dir/t_sys_file_autoflush/t_sys_file_autoflush.log","w");
+      file = $fopen({`STRINGIFY(`TEST_OBJ_DIR),"/t_sys_file_autoflush.log"},"w");
 `else
       // The "w" is required so we get a FD not a MFD
-      file = $fopen("obj_dir/t_sys_file_basic/t_sys_file_basic_test.log","w");
+      file = $fopen({`STRINGIFY(`TEST_OBJ_DIR),"/t_sys_file_basic_test.log"},"w");
 `endif
       if ($feof(file)) $stop;
 
@@ -56,7 +58,7 @@ module t;
       begin
 	 // Check for opening errors
 	 // The "r" is required so we get a FD not a MFD
-	 file = $fopen("obj_dir/t_sys_file_basic/DOES_NOT_EXIST","r");
+         file = $fopen("DOES_NOT_EXIST","r");
 	 if (|file) $stop;	// Should not exist, IE must return 0
       end
 
diff --git a/test_regress/t/t_sys_file_scan.pl b/test_regress/t/t_sys_file_scan.pl
index 3a610d7c3..037bb339b 100755
--- a/test_regress/t/t_sys_file_scan.pl
+++ b/test_regress/t/t_sys_file_scan.pl
@@ -7,16 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 unlink("$Self->{obj_dir}/t_sys_file_scan_test.log");
 
-compile (
-	 );
+compile(
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
-file_grep ("$Self->{obj_dir}/t_sys_file_scan_test.log",
+file_grep("$Self->{obj_dir}/t_sys_file_scan_test.log",
 "# a
           1
 ");
diff --git a/test_regress/t/t_sys_file_scan.v b/test_regress/t/t_sys_file_scan.v
index 1bb4ea4a6..30efafadf 100644
--- a/test_regress/t/t_sys_file_scan.v
+++ b/test_regress/t/t_sys_file_scan.v
@@ -5,13 +5,15 @@
 
 `include "verilated.v"
 
+`define STRINGIFY(x) `"x`"
+
 module t;
    `verilator_file_descriptor infile, outfile;
    integer count, a;
 
    initial begin
       infile = $fopen("t/t_sys_file_scan_input.dat", "r");
-      outfile = $fopen("obj_dir/t_sys_file_scan/t_sys_file_scan_test.log", "w");
+      outfile = $fopen({`STRINGIFY(`TEST_OBJ_DIR),"/t_sys_file_scan_test.log"}, "w");
 
       count = 1234;
 `ifdef TEST_VERBOSE
diff --git a/test_regress/t/t_sys_plusargs.pl b/test_regress/t/t_sys_plusargs.pl
index a58e3c1f8..587bd97e3 100755
--- a/test_regress/t/t_sys_plusargs.pl
+++ b/test_regress/t/t_sys_plusargs.pl
@@ -1,14 +1,22 @@
 #!/usr/bin/perl
 if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
 
-compile (
-	 v_flags2 => ['-v', 't/t_flag_libinc.v'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 all_run_flags => ['+PLUS +INT=1234 +STRSTR'],
-     );
+compile(
+    v_flags2 => ['-v', 't/t_flag_libinc.v'],
+    );
+
+execute(
+    check_finished => 1,
+    all_run_flags => ['+PLUS +INT=1234 +STRSTR'],
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sys_plusargs_bad.pl b/test_regress/t/t_sys_plusargs_bad.pl
index 4f0058853..c9adf6d32 100755
--- a/test_regress/t/t_sys_plusargs_bad.pl
+++ b/test_regress/t/t_sys_plusargs_bad.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_sys_rand.pl b/test_regress/t/t_sys_rand.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_sys_rand.pl
+++ b/test_regress/t/t_sys_rand.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sys_readmem.pl b/test_regress/t/t_sys_readmem.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_sys_readmem.pl
+++ b/test_regress/t/t_sys_readmem.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sys_readmem_bad_addr.pl b/test_regress/t/t_sys_readmem_bad_addr.pl
index ba732c4f1..f2a330eeb 100755
--- a/test_regress/t/t_sys_readmem_bad_addr.pl
+++ b/test_regress/t/t_sys_readmem_bad_addr.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    );
+
+execute(
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_sys_readmem_bad_addr.mem:\d+: \$readmem file address beyond bounds of array',
-     );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sys_readmem_bad_digit.pl b/test_regress/t/t_sys_readmem_bad_digit.pl
index 744ac56a1..e9af99d49 100755
--- a/test_regress/t/t_sys_readmem_bad_digit.pl
+++ b/test_regress/t/t_sys_readmem_bad_digit.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    );
+
+execute(
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_sys_readmem_bad_digit.mem:\d+: \$readmemb \(binary\) file contains hex characters',
-     );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sys_readmem_bad_end.pl b/test_regress/t/t_sys_readmem_bad_end.pl
index fe6606021..17603bbbf 100755
--- a/test_regress/t/t_sys_readmem_bad_end.pl
+++ b/test_regress/t/t_sys_readmem_bad_end.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    );
+
+execute(
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_sys_readmem_bad_end.mem:\d+: \$readmem file ended before specified ending-address',
-     );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sys_readmem_bad_notfound.pl b/test_regress/t/t_sys_readmem_bad_notfound.pl
index 1b9384fca..30677cb48 100755
--- a/test_regress/t/t_sys_readmem_bad_notfound.pl
+++ b/test_regress/t/t_sys_readmem_bad_notfound.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    );
+
+execute(
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_sys_readmem_bad_NOTFOUND.mem:\d+: \$readmem file not found',
-     );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sys_sformat.pl b/test_regress/t/t_sys_sformat.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_sys_sformat.pl
+++ b/test_regress/t/t_sys_sformat.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sys_sformat_noopt.pl b/test_regress/t/t_sys_sformat_noopt.pl
index c6d831138..dc7e03f51 100755
--- a/test_regress/t/t_sys_sformat_noopt.pl
+++ b/test_regress/t/t_sys_sformat_noopt.pl
@@ -7,20 +7,22 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_sys_sformat.v");
 
-compile (
+compile(
     # Avoid inlining our simple example, to make sure verilated.h works right
     verilator_flags2 => ["-O0"],
     );
 
 if ($Self->cxx_version =~ /clang version ([0-9]+\.[0-9]+)/
     && ($1 >= 3.8 && $1 <= 5.0)) {
-    $Self->skip("Known clang bug");
+    skip("Known clang bug");
     #Here:   if (VL_UNLIKELY(VL_NEQ_W(12, __Vtemp1, vlSymsp->TOP__t.__PVT__str)))
 } else{
-    execute (
-        check_finished=>1,
+    execute(
+        check_finished => 1,
         );
 }
 
diff --git a/test_regress/t/t_sys_system.pl b/test_regress/t/t_sys_system.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_sys_system.pl
+++ b/test_regress/t/t_sys_system.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sys_time.pl b/test_regress/t/t_sys_time.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_sys_time.pl
+++ b/test_regress/t/t_sys_time.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_sys_writemem.pl b/test_regress/t/t_sys_writemem.pl
index 523a44835..29bdb8210 100755
--- a/test_regress/t/t_sys_writemem.pl
+++ b/test_regress/t/t_sys_writemem.pl
@@ -7,6 +7,8 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_sys_readmem.v");
 
 # Use random reset to ensure we're fully initializing arrays before
@@ -22,8 +24,8 @@ compile(v_flags2 => [
             "+define+OUT_TMP5=\\\"$Self->{obj_dir}/tmp5.mem\\\"",
         ]);
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 for (my $i = 1; $i <= 5; $i++) {
@@ -33,7 +35,7 @@ for (my $i = 1; $i <= 5; $i++) {
     my @diffs = `diff $gold $out`;
     if (0 < scalar @diffs) {
         print @diffs;
-        $Self->error("Got unexpected diffs against gold.");
+        error("Got unexpected diffs against gold.");
     }
 }
 
diff --git a/test_regress/t/t_table_fsm.pl b/test_regress/t/t_table_fsm.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_table_fsm.pl
+++ b/test_regress/t/t_table_fsm.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_threads_counter_0.pl b/test_regress/t/t_threads_counter_0.pl
index 3bcf004fd..b7ad02b32 100755
--- a/test_regress/t/t_threads_counter_0.pl
+++ b/test_regress/t/t_threads_counter_0.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_threads_counter.v");
 
-compile (
+compile(
     verilator_flags2 => ['--cc --no-threads'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_threads_counter_1.pl b/test_regress/t/t_threads_counter_1.pl
index 186cc575e..2f4f64743 100755
--- a/test_regress/t/t_threads_counter_1.pl
+++ b/test_regress/t/t_threads_counter_1.pl
@@ -7,16 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("No thread support") if !$Self->cfg_with_threaded;
+scenarios(simulator => 1);
+$Self->cfg_with_threaded or skip("No thread support");
 
 top_filename("t/t_threads_counter.v");
 
-compile (
+compile(
     verilator_flags2 => ['--cc --threads 1'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_threads_counter_2.pl b/test_regress/t/t_threads_counter_2.pl
index 3a7c975fb..e016b8253 100755
--- a/test_regress/t/t_threads_counter_2.pl
+++ b/test_regress/t/t_threads_counter_2.pl
@@ -7,16 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("No thread support") if !$Self->cfg_with_threaded;
+scenarios(simulator => 1);
+$Self->cfg_with_threaded or skip("No thread support");
 
 top_filename("t/t_threads_counter.v");
 
-compile (
+compile(
     verilator_flags2 => ['--cc --threads 2'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_trace_array.pl b/test_regress/t/t_trace_array.pl
index 12e9fb138..09cc25625 100755
--- a/test_regress/t/t_trace_array.pl
+++ b/test_regress/t/t_trace_array.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--cc --trace --trace-structs'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 file_grep     ("$Self->{obj_dir}/simx.vcd", qr/\$enddefinitions/x);
diff --git a/test_regress/t/t_trace_cat.cpp b/test_regress/t/t_trace_cat.cpp
index 27978f647..dc8256350 100644
--- a/test_regress/t/t_trace_cat.cpp
+++ b/test_regress/t/t_trace_cat.cpp
@@ -10,6 +10,9 @@
 
 #include VM_PREFIX_INCLUDE
 
+#define STRINGIFY(x) STRINGIFY2(x)
+#define STRINGIFY2(x) #x
+
 unsigned long long main_time = 0;
 double sc_time_stamp() {
     return (double)main_time;
@@ -17,15 +20,7 @@ double sc_time_stamp() {
 
 const char* trace_name() {
     static char name[1000];
-#if defined(T_TRACE_CAT)
-    VL_SNPRINTF(name,1000,"obj_dir/t_trace_cat/simpart_%04d.vcd", (int)main_time);
-#elif defined(T_TRACE_CAT_REOPEN)
-    VL_SNPRINTF(name,1000,"obj_dir/t_trace_cat_reopen/simpart_%04d.vcd", (int)main_time);
-#elif defined(T_TRACE_CAT_RENEW)
-    VL_SNPRINTF(name,1000,"obj_dir/t_trace_cat_renew/simpart_%04d.vcd", (int)main_time);
-#else
-# error "Unknown test"
-#endif
+    VL_SNPRINTF(name, 1000, STRINGIFY(TEST_OBJ_DIR) "/simpart_%04d.vcd", (int)main_time);
     return name;
 }
 
diff --git a/test_regress/t/t_trace_cat.pl b/test_regress/t/t_trace_cat.pl
index 272de8c92..8ff497018 100755
--- a/test_regress/t/t_trace_cat.pl
+++ b/test_regress/t/t_trace_cat.pl
@@ -7,22 +7,22 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     v_flags2 => ["--trace --exe $Self->{t_dir}/t_trace_cat.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 system("cat $Self->{obj_dir}/simpart*.vcd > $Self->{obj_dir}/simall.vcd");
 
-vcd_identical ("$Self->{obj_dir}/simall.vcd",
-	       "t/$Self->{name}.out");
+vcd_identical("$Self->{obj_dir}/simall.vcd",
+              "t/$Self->{name}.out");
 
 ok(1);
 1;
diff --git a/test_regress/t/t_trace_cat_renew.pl b/test_regress/t/t_trace_cat_renew.pl
index a42810232..7ab142802 100755
--- a/test_regress/t/t_trace_cat_renew.pl
+++ b/test_regress/t/t_trace_cat_renew.pl
@@ -7,24 +7,24 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t_trace_cat.v");
 
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     v_flags2 => ["--trace --exe $Self->{t_dir}/t_trace_cat.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
-vcd_identical ("$Self->{obj_dir}/simpart_0000.vcd",
-	       "t/$Self->{name}_0000.out");
-vcd_identical ("$Self->{obj_dir}/simpart_0100.vcd",
-	       "t/$Self->{name}_0100.out");
+vcd_identical("$Self->{obj_dir}/simpart_0000.vcd",
+              "t/$Self->{name}_0000.out");
+vcd_identical("$Self->{obj_dir}/simpart_0100.vcd",
+              "t/$Self->{name}_0100.out");
 
 ok(1);
 1;
diff --git a/test_regress/t/t_trace_cat_reopen.pl b/test_regress/t/t_trace_cat_reopen.pl
index a42810232..7ab142802 100755
--- a/test_regress/t/t_trace_cat_reopen.pl
+++ b/test_regress/t/t_trace_cat_reopen.pl
@@ -7,24 +7,24 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t_trace_cat.v");
 
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     v_flags2 => ["--trace --exe $Self->{t_dir}/t_trace_cat.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
-vcd_identical ("$Self->{obj_dir}/simpart_0000.vcd",
-	       "t/$Self->{name}_0000.out");
-vcd_identical ("$Self->{obj_dir}/simpart_0100.vcd",
-	       "t/$Self->{name}_0100.out");
+vcd_identical("$Self->{obj_dir}/simpart_0000.vcd",
+              "t/$Self->{name}_0000.out");
+vcd_identical("$Self->{obj_dir}/simpart_0100.vcd",
+              "t/$Self->{name}_0100.out");
 
 ok(1);
 1;
diff --git a/test_regress/t/t_trace_complex.pl b/test_regress/t/t_trace_complex.pl
index 1e6cacc6c..fa1699b30 100755
--- a/test_regress/t/t_trace_complex.pl
+++ b/test_regress/t/t_trace_complex.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ['--cc --trace'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    verilator_flags2 => ['--cc --trace'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 file_grep     ("$Self->{obj_dir}/simx.vcd", qr/ v_strp /);
 file_grep     ("$Self->{obj_dir}/simx.vcd", qr/ v_strp_strp /);
diff --git a/test_regress/t/t_trace_complex_params.pl b/test_regress/t/t_trace_complex_params.pl
index 5979d34ff..48a06b82e 100755
--- a/test_regress/t/t_trace_complex_params.pl
+++ b/test_regress/t/t_trace_complex_params.pl
@@ -7,19 +7,21 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t_trace_complex.v");
 
-compile (
-	 verilator_flags2 => ['--cc --trace --no-trace-structs --trace-params'],
-	 );
+compile(
+    verilator_flags2 => ['--cc --trace --no-trace-structs --trace-params'],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 file_grep     ("$Self->{obj_dir}/simx.vcd", qr/ PARAM /);
 
-vcd_identical ("$Self->{obj_dir}/simx.vcd", "t/$Self->{name}.out");
+vcd_identical("$Self->{obj_dir}/simx.vcd", "t/$Self->{name}.out");
 
 ok(1);
 1;
diff --git a/test_regress/t/t_trace_complex_structs.pl b/test_regress/t/t_trace_complex_structs.pl
index cf1ca30c9..7f0530dca 100755
--- a/test_regress/t/t_trace_complex_structs.pl
+++ b/test_regress/t/t_trace_complex_structs.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t_trace_complex.v");
 
-compile (
-	 verilator_flags2 => ['--cc --trace --trace-structs --no-trace-params'],
-	 );
+compile(
+    verilator_flags2 => ['--cc --trace --trace-structs --no-trace-params'],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 file_grep     ("$Self->{obj_dir}/simx.vcd", qr/ v_strp /);
 file_grep     ("$Self->{obj_dir}/simx.vcd", qr/ v_strp_strp /);
diff --git a/test_regress/t/t_trace_decoration.pl b/test_regress/t/t_trace_decoration.pl
index e8744e81d..f63f24f0a 100755
--- a/test_regress/t/t_trace_decoration.pl
+++ b/test_regress/t/t_trace_decoration.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--cc --trace --no-decoration'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 file_grep_not ("$Self->{obj_dir}/$Self->{VM_PREFIX}.h", qr!// Body!x);
diff --git a/test_regress/t/t_trace_ena_cc.pl b/test_regress/t/t_trace_ena_cc.pl
index 899c1c275..c26fdb7fe 100755
--- a/test_regress/t/t_trace_ena_cc.pl
+++ b/test_regress/t/t_trace_ena_cc.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_trace_ena.v");
 
-compile (
+compile(
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 if ($Self->{vlt}) {
diff --git a/test_regress/t/t_trace_ena_sc.pl b/test_regress/t/t_trace_ena_sc.pl
index 4f5d30882..d05bb369b 100755
--- a/test_regress/t/t_trace_ena_sc.pl
+++ b/test_regress/t/t_trace_ena_sc.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 if (!$Self->have_sc) {
-    $Self->skip("No SystemC installed");
+    skip("No SystemC installed");
 }
 else {
     top_filename("t/t_trace_ena.v");
 
-    compile (
+    compile(
         verilator_flags2 => ['-trace -sc'],
         );
 
-    execute (
-        check_finished=>1,
+    execute(
+        check_finished => 1,
         );
 
     if ($Self->{vlt}) {
diff --git a/test_regress/t/t_trace_off_cc.pl b/test_regress/t/t_trace_off_cc.pl
index da3f35561..33c430ccb 100755
--- a/test_regress/t/t_trace_off_cc.pl
+++ b/test_regress/t/t_trace_off_cc.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_trace_ena.v");
 
-compile (
-	 verilator_flags2 => ['-notrace'],
-	 );
+compile(
+    verilator_flags2 => ['-notrace'],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 if ($Self->{vlt}) {
-    !-r "$Self->{obj_dir}/simx.vcd" or $Self->error("Tracing should be off\n");
+    !-r "$Self->{obj_dir}/simx.vcd" or error("Tracing should be off\n");
 }
 
 ok(1);
diff --git a/test_regress/t/t_trace_off_sc.pl b/test_regress/t/t_trace_off_sc.pl
index 009dadb33..e1865f560 100755
--- a/test_regress/t/t_trace_off_sc.pl
+++ b/test_regress/t/t_trace_off_sc.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_trace_ena.v");
 
-compile (
-	 verilator_flags2 => ['-notrace -sc'],
-	 );
+compile(
+    verilator_flags2 => ['-notrace -sc'],
+    );
 
-execute (
-	 check_finished=>1,
-	 );
+execute(
+    check_finished => 1,
+    );
 
 if ($Self->{vlt}) {
-    !-r "$Self->{obj_dir}/simx.vcd" or $Self->error("Tracing should be off\n");
+    !-r "$Self->{obj_dir}/simx.vcd" or error("Tracing should be off\n");
 }
 
 ok(1);
diff --git a/test_regress/t/t_trace_packed_struct.pl b/test_regress/t/t_trace_packed_struct.pl
index f1d1f6c41..a25a14034 100755
--- a/test_regress/t/t_trace_packed_struct.pl
+++ b/test_regress/t/t_trace_packed_struct.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--trace"]
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_trace_param.pl b/test_regress/t/t_trace_param.pl
index abf8ed786..527cc3283 100755
--- a/test_regress/t/t_trace_param.pl
+++ b/test_regress/t/t_trace_param.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--trace"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_trace_primitive.pl b/test_regress/t/t_trace_primitive.pl
index 17dfb5e3d..ad5c14ca8 100755
--- a/test_regress/t/t_trace_primitive.pl
+++ b/test_regress/t/t_trace_primitive.pl
@@ -7,16 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--trace"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 if ($Self->{vlt}) {
-   file_grep ("$Self->{obj_dir}/simx.vcd", "sub_t_i");
+   file_grep("$Self->{obj_dir}/simx.vcd", "sub_t_i");
 };
 
 ok(1);
diff --git a/test_regress/t/t_trace_public_func.cpp b/test_regress/t/t_trace_public_func.cpp
index a69bbca8d..e47283715 100644
--- a/test_regress/t/t_trace_public_func.cpp
+++ b/test_regress/t/t_trace_public_func.cpp
@@ -12,6 +12,9 @@
 #include "Vt_trace_public_func_t.h"
 #include "Vt_trace_public_func_glbl.h"
 
+#define STRINGIFY(x) STRINGIFY2(x)
+#define STRINGIFY2(x) #x
+
 unsigned long long main_time = 0;
 double sc_time_stamp() {
     return (double)main_time;
@@ -27,7 +30,7 @@ int main(int argc, char **argv, char **env) {
 
     VerilatedVcdC* tfp = new VerilatedVcdC;
     top->trace(tfp,99);
-    tfp->open("obj_dir/t_trace_public_func/simx.vcd");
+    tfp->open(STRINGIFY(TEST_OBJ_DIR) "/simx.vcd");
 
     while (main_time <= 20) {
 	top->CLK   = (main_time/dt_2)%2;
diff --git a/test_regress/t/t_trace_public_func.pl b/test_regress/t/t_trace_public_func.pl
index d9d882a3c..a8fa99330 100755
--- a/test_regress/t/t_trace_public_func.pl
+++ b/test_regress/t/t_trace_public_func.pl
@@ -7,22 +7,22 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_trace_public.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     v_flags2 => ["-DPUB_FUNC --trace --exe $Self->{t_dir}/$Self->{name}.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
-vcd_identical ("$Self->{obj_dir}/simx.vcd",
-	       "t/t_trace_public.out");
+vcd_identical("$Self->{obj_dir}/simx.vcd",
+              "t/t_trace_public.out");
 
 ok(1);
 1;
diff --git a/test_regress/t/t_trace_public_sig.cpp b/test_regress/t/t_trace_public_sig.cpp
index 03283a514..2a437729a 100644
--- a/test_regress/t/t_trace_public_sig.cpp
+++ b/test_regress/t/t_trace_public_sig.cpp
@@ -12,6 +12,9 @@
 #include "Vt_trace_public_sig_t.h"
 #include "Vt_trace_public_sig_glbl.h"
 
+#define STRINGIFY(x) STRINGIFY2(x)
+#define STRINGIFY2(x) #x
+
 unsigned long long main_time = 0;
 double sc_time_stamp() {
     return (double)main_time;
@@ -27,7 +30,7 @@ int main(int argc, char **argv, char **env) {
 
     VerilatedVcdC* tfp = new VerilatedVcdC;
     top->trace(tfp,99);
-    tfp->open("obj_dir/t_trace_public_sig/simx.vcd");
+    tfp->open(STRINGIFY(TEST_OBJ_DIR) "/simx.vcd");
 
     while (main_time <= 20) {
 	top->CLK   = (main_time/dt_2)%2;
diff --git a/test_regress/t/t_trace_public_sig.pl b/test_regress/t/t_trace_public_sig.pl
index 45eace968..7d69b207c 100755
--- a/test_regress/t/t_trace_public_sig.pl
+++ b/test_regress/t/t_trace_public_sig.pl
@@ -7,25 +7,25 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_trace_public.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     v_flags2 => ["--trace --exe $Self->{t_dir}/$Self->{name}.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
-vcd_identical ("$Self->{obj_dir}/simx.vcd",
-	       "t/t_trace_public.out");
+vcd_identical("$Self->{obj_dir}/simx.vcd",
+              "t/t_trace_public.out");
 
 # vcd_identical doesn't detect "$var a.b;" vs "$scope module a; $var b;"
-file_grep ("$Self->{obj_dir}/simx.vcd", qr/module glbl/i);
+file_grep("$Self->{obj_dir}/simx.vcd", qr/module glbl/i);
 
 ok(1);
 1;
diff --git a/test_regress/t/t_trace_scstruct.pl b/test_regress/t/t_trace_scstruct.pl
index 9c08b40ef..51382a932 100755
--- a/test_regress/t/t_trace_scstruct.pl
+++ b/test_regress/t/t_trace_scstruct.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--sc --trace --trace-structs --pins-bv 2'],
     );
 
-#execute ();  # didn't bother with top shell
+#execute();  # didn't bother with top shell
 
 ok(1);
 1;
diff --git a/test_regress/t/t_trace_timescale.cpp b/test_regress/t/t_trace_timescale.cpp
index 284a8515a..d1bddcd38 100644
--- a/test_regress/t/t_trace_timescale.cpp
+++ b/test_regress/t/t_trace_timescale.cpp
@@ -10,6 +10,9 @@
 
 #include VM_PREFIX_INCLUDE
 
+#define STRINGIFY(x) STRINGIFY2(x)
+#define STRINGIFY2(x) #x
+
 unsigned long long main_time = 0;
 double sc_time_stamp() {
     return ((double)main_time) / VL_TIME_MULTIPLIER;
@@ -27,7 +30,7 @@ int main(int argc, char **argv, char **env) {
 
     top->trace(tfp,99);
 
-    tfp->open("obj_dir/t_trace_timescale/t_trace_timescale.vcd");
+    tfp->open(STRINGIFY(TEST_OBJ_DIR) "/simx.vcd");
 
     top->clk = 0;
 
diff --git a/test_regress/t/t_trace_timescale.pl b/test_regress/t/t_trace_timescale.pl
index 0b2f13c0a..6d186b276 100755
--- a/test_regress/t/t_trace_timescale.pl
+++ b/test_regress/t/t_trace_timescale.pl
@@ -7,21 +7,21 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     v_flags2 => ["--trace --exe $Self->{t_dir}/t_trace_timescale.cpp"],
     make_flags => 'CPPFLAGS_ADD=-DVL_TIME_MULTIPLIER=1000',
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
-vcd_identical ("$Self->{obj_dir}/$Self->{name}.vcd",
-	       "t/$Self->{name}.out");
+vcd_identical("$Self->{obj_dir}/simx.vcd",
+              "t/$Self->{name}.out");
 
 ok(1);
 1;
diff --git a/test_regress/t/t_tri_array.pl b/test_regress/t/t_tri_array.pl
index cc522f7b4..3dc957163 100755
--- a/test_regress/t/t_tri_array.pl
+++ b/test_regress/t/t_tri_array.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-# When fix, update ifdefs in t_sv_cpu files; search for t_tri_array
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, tristate arrays");
+scenarios(simulator => 1);
 
-compile (
+# When fix, update ifdefs in t_sv_cpu files; search for t_tri_array
+$Self->{vlt} and unsupported("Verilator unsupported, tristate arrays");
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_array_bufif.pl b/test_regress/t/t_tri_array_bufif.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_tri_array_bufif.pl
+++ b/test_regress/t/t_tri_array_bufif.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_tri_array_pull.pl b/test_regress/t/t_tri_array_pull.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_tri_array_pull.pl
+++ b/test_regress/t/t_tri_array_pull.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_dangle.pl b/test_regress/t/t_tri_dangle.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_tri_dangle.pl
+++ b/test_regress/t/t_tri_dangle.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_tri_eqcase.pl b/test_regress/t/t_tri_eqcase.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_tri_eqcase.pl
+++ b/test_regress/t/t_tri_eqcase.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_tri_gate_bufif0.pl b/test_regress/t/t_tri_gate_bufif0.pl
index d3b38fe3d..f7f617e73 100755
--- a/test_regress/t/t_tri_gate_bufif0.pl
+++ b/test_regress/t/t_tri_gate_bufif0.pl
@@ -7,20 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_tri_gate.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 v_flags2 => ['+define+T_BUFIF0',],
-	 make_flags => 'CPPFLAGS_ADD=-DT_BUFIF0',
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    v_flags2 => ['+define+T_BUFIF0',],
+    make_flags => 'CPPFLAGS_ADD=-DT_BUFIF0',
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_gate_bufif1.pl b/test_regress/t/t_tri_gate_bufif1.pl
index 45e566012..1e1ba6013 100755
--- a/test_regress/t/t_tri_gate_bufif1.pl
+++ b/test_regress/t/t_tri_gate_bufif1.pl
@@ -1,5 +1,4 @@
 #!/usr/bin/perl
-if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
 # DESCRIPTION: Verilator: Verilog Test driver/expect definition
 #
 # Copyright 2003-2009 by Wilson Snyder. This program is free software; you can
@@ -7,20 +6,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_tri_gate.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 v_flags2 => ['+define+T_BUFIF1',],
-	 make_flags => 'CPPFLAGS_ADD=-DT_BUFIF1',
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    v_flags2 => ['+define+T_BUFIF1',],
+    make_flags => 'CPPFLAGS_ADD=-DT_BUFIF1',
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_gate_cond.pl b/test_regress/t/t_tri_gate_cond.pl
index a86dc81a2..41695b762 100755
--- a/test_regress/t/t_tri_gate_cond.pl
+++ b/test_regress/t/t_tri_gate_cond.pl
@@ -7,20 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_tri_gate.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 v_flags2 => ['+define+T_COND',],
-	 make_flags => 'CPPFLAGS_ADD=-DT_COND',
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    v_flags2 => ['+define+T_COND',],
+    make_flags => 'CPPFLAGS_ADD=-DT_COND',
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_gate_nmos.pl b/test_regress/t/t_tri_gate_nmos.pl
index ea2b89c32..024edd03e 100755
--- a/test_regress/t/t_tri_gate_nmos.pl
+++ b/test_regress/t/t_tri_gate_nmos.pl
@@ -7,20 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_tri_gate.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 v_flags2 => ['+define+T_NMOS',],
-	 make_flags => 'CPPFLAGS_ADD=-DT_NMOS',
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    v_flags2 => ['+define+T_NMOS',],
+    make_flags => 'CPPFLAGS_ADD=-DT_NMOS',
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_gate_notif0.pl b/test_regress/t/t_tri_gate_notif0.pl
index 531f9bdf0..d0bd5f0ec 100755
--- a/test_regress/t/t_tri_gate_notif0.pl
+++ b/test_regress/t/t_tri_gate_notif0.pl
@@ -7,20 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_tri_gate.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 v_flags2 => ['+define+T_NOTIF0',],
-	 make_flags => 'CPPFLAGS_ADD=-DT_NOTIF0',
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    v_flags2 => ['+define+T_NOTIF0',],
+    make_flags => 'CPPFLAGS_ADD=-DT_NOTIF0',
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_gate_notif1.pl b/test_regress/t/t_tri_gate_notif1.pl
index 88bbc13d5..ba4d5997e 100755
--- a/test_regress/t/t_tri_gate_notif1.pl
+++ b/test_regress/t/t_tri_gate_notif1.pl
@@ -7,20 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_tri_gate.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 v_flags2 => ['+define+T_NOTIF1',],
-	 make_flags => 'CPPFLAGS_ADD=-DT_NOTIF1',
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    v_flags2 => ['+define+T_NOTIF1',],
+    make_flags => 'CPPFLAGS_ADD=-DT_NOTIF1',
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_gate_pmos.pl b/test_regress/t/t_tri_gate_pmos.pl
index f61945fae..5cc799f74 100755
--- a/test_regress/t/t_tri_gate_pmos.pl
+++ b/test_regress/t/t_tri_gate_pmos.pl
@@ -7,20 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_tri_gate.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 v_flags2 => ['+define+T_PMOS',],
-	 make_flags => 'CPPFLAGS_ADD=-DT_PMOS',
-	 verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    v_flags2 => ['+define+T_PMOS',],
+    make_flags => 'CPPFLAGS_ADD=-DT_PMOS',
+    verilator_flags2 => ["--exe $Self->{t_dir}/t_tri_gate.cpp"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_gen.pl b/test_regress/t/t_tri_gen.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_tri_gen.pl
+++ b/test_regress/t/t_tri_gen.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_tri_graph.pl b/test_regress/t/t_tri_graph.pl
index 3d2231550..6312119ef 100755
--- a/test_regress/t/t_tri_graph.pl
+++ b/test_regress/t/t_tri_graph.pl
@@ -7,8 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # Compile only test
-compile (
+compile(
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_ifbegin.pl b/test_regress/t/t_tri_ifbegin.pl
index fb2f3bf0c..96d9ccfa3 100755
--- a/test_regress/t/t_tri_ifbegin.pl
+++ b/test_regress/t/t_tri_ifbegin.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
 # No exeecution
diff --git a/test_regress/t/t_tri_inout.pl b/test_regress/t/t_tri_inout.pl
index e1b68002f..6c781245e 100755
--- a/test_regress/t/t_tri_inout.pl
+++ b/test_regress/t/t_tri_inout.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_inout2.pl b/test_regress/t/t_tri_inout2.pl
index cdae47250..9904360ae 100755
--- a/test_regress/t/t_tri_inout2.pl
+++ b/test_regress/t/t_tri_inout2.pl
@@ -6,12 +6,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # redistribute it and/or modify it under the terms of either the GNU
 # General Public License or the Perl Artistic License.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_tri_inz.pl b/test_regress/t/t_tri_inz.pl
index be0af3f3d..e50597b5e 100755
--- a/test_regress/t/t_tri_inz.pl
+++ b/test_regress/t/t_tri_inz.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_public.pl b/test_regress/t/t_tri_public.pl
index 3d2231550..6312119ef 100755
--- a/test_regress/t/t_tri_public.pl
+++ b/test_regress/t/t_tri_public.pl
@@ -7,8 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # Compile only test
-compile (
+compile(
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_pull01.pl b/test_regress/t/t_tri_pull01.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_tri_pull01.pl
+++ b/test_regress/t/t_tri_pull01.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_tri_pull2_bad.pl b/test_regress/t/t_tri_pull2_bad.pl
index 185d1b763..c2de1b6e9 100755
--- a/test_regress/t/t_tri_pull2_bad.pl
+++ b/test_regress/t/t_tri_pull2_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_tri_pull2_bad.v:\d+: Unsupported: Conflicting pull directions.
 %Error: t/t_tri_pull2_bad.v:\d+: ... Location of conflicting pull.
 %Error: Exiting due to',
diff --git a/test_regress/t/t_tri_pull_bad.pl b/test_regress/t/t_tri_pull_bad.pl
index f1244c602..1e7247324 100755
--- a/test_regress/t/t_tri_pull_bad.pl
+++ b/test_regress/t/t_tri_pull_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_tri_pull_bad.v:\d+: Unsupported: Conflicting pull directions.
 %Error: t/t_tri_pull_bad.v:\d+: ... Location of conflicting pull.
 %Error: Exiting due to',
diff --git a/test_regress/t/t_tri_pullup.pl b/test_regress/t/t_tri_pullup.pl
index e1b68002f..6c781245e 100755
--- a/test_regress/t/t_tri_pullup.pl
+++ b/test_regress/t/t_tri_pullup.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_pullvec_bad.pl b/test_regress/t/t_tri_pullvec_bad.pl
index 8c2848e04..ebc9922ca 100755
--- a/test_regress/t/t_tri_pullvec_bad.pl
+++ b/test_regress/t/t_tri_pullvec_bad.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>$Self->{v3},
-    expect=>
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_tri_pullvec_bad.v:\d+: Unsupported: Conflicting pull directions.
 %Error: t/t_tri_pullvec_bad.v:\d+: ... Location of conflicting pull.
 %Error: t/t_tri_pullvec_bad.v:\d+: Unsupported: Conflicting pull directions.
diff --git a/test_regress/t/t_tri_select.pl b/test_regress/t/t_tri_select.pl
index e1b68002f..6c781245e 100755
--- a/test_regress/t/t_tri_select.pl
+++ b/test_regress/t/t_tri_select.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["--exe $Self->{t_dir}/$Self->{name}.cpp"],
     );
 
-execute (
-	 check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_select_unsized.pl b/test_regress/t/t_tri_select_unsized.pl
index 2051c3122..bbe51465d 100755
--- a/test_regress/t/t_tri_select_unsized.pl
+++ b/test_regress/t/t_tri_select_unsized.pl
@@ -7,8 +7,10 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 # Compile only test
-compile (
+compile(
     verilator_flags2 => ["-Wno-WIDTH"],
     );
 
diff --git a/test_regress/t/t_tri_unconn.pl b/test_regress/t/t_tri_unconn.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_tri_unconn.pl
+++ b/test_regress/t/t_tri_unconn.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_tri_various.pl b/test_regress/t/t_tri_various.pl
index db0de10ee..1be18a66c 100755
--- a/test_regress/t/t_tri_various.pl
+++ b/test_regress/t/t_tri_various.pl
@@ -1,12 +1,20 @@
 #!/usr/bin/perl
 if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003-2009 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_typedef.pl b/test_regress/t/t_typedef.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_typedef.pl
+++ b/test_regress/t/t_typedef.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_typedef_array.pl b/test_regress/t/t_typedef_array.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_typedef_array.pl
+++ b/test_regress/t/t_typedef_array.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_typedef_param.pl b/test_regress/t/t_typedef_param.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_typedef_param.pl
+++ b/test_regress/t/t_typedef_param.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_typedef_port.pl b/test_regress/t/t_typedef_port.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_typedef_port.pl
+++ b/test_regress/t/t_typedef_port.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_typedef_signed.pl b/test_regress/t/t_typedef_signed.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_typedef_signed.pl
+++ b/test_regress/t/t_typedef_signed.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_udp_bad.pl b/test_regress/t/t_udp_bad.pl
index 49c258096..cf7375ce5 100755
--- a/test_regress/t/t_udp_bad.pl
+++ b/test_regress/t/t_udp_bad.pl
@@ -7,17 +7,19 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_udp.v");
 
-compile (
-	 fails=>$Self->{vlt},
-	 expect=>
+compile(
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_udp.v:\d+: Unsupported: Verilog 1995 UDP Tables.  Use --bbox-unsup to ignore tables.
 %Error: Exiting due to '
-	 );
+    );
 
-execute (
-     ) if !$Self->{vlt};
+execute(
+    ) if !$Self->{vlt};
 
 ok(1);
 1;
diff --git a/test_regress/t/t_udp_lint.pl b/test_regress/t/t_udp_lint.pl
index 718e795a3..38f3852a1 100755
--- a/test_regress/t/t_udp_lint.pl
+++ b/test_regress/t/t_udp_lint.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_udp.v");
 
-compile (
+compile(
     # Unsupported: UDP Tables
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_udp_noname.pl b/test_regress/t/t_udp_noname.pl
index e6cf2a5b4..e1cea4cf7 100755
--- a/test_regress/t/t_udp_noname.pl
+++ b/test_regress/t/t_udp_noname.pl
@@ -7,13 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, bug468");
+scenarios(simulator => 1);
+$Self->{vlt} and unsupported("Verilator unsupported, bug468");
 
-compile (
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_uniqueif.pl b/test_regress/t/t_uniqueif.pl
index 4eada89db..f97a8c4aa 100755
--- a/test_regress/t/t_uniqueif.pl
+++ b/test_regress/t/t_uniqueif.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['--assert'],
     nc_flags2 => ['+assert'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_uniqueif_fail1.pl b/test_regress/t/t_uniqueif_fail1.pl
index 19b745598..5f05d5e83 100755
--- a/test_regress/t/t_uniqueif_fail1.pl
+++ b/test_regress/t/t_uniqueif_fail1.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_uniqueif.v");
 
-compile (
+compile(
     v_flags2 => ['+define+FAILING_ASSERTION1'],
     verilator_flags2 => ['--assert'],
     nc_flags2 => ['+assert'],
     fails => $Self->{nc},
     );
 
-execute (
+execute(
     fails => $Self->{vlt},
-    expect=>
+    expect =>
 '.*%Error: t_uniqueif.v:\d+: Assertion failed in top.t: \'unique if\' statement violated
 %Error: t/t_uniqueif.v:\d+: Verilog \$stop
 .*',
diff --git a/test_regress/t/t_uniqueif_fail2.pl b/test_regress/t/t_uniqueif_fail2.pl
index a534ca47b..621a91162 100755
--- a/test_regress/t/t_uniqueif_fail2.pl
+++ b/test_regress/t/t_uniqueif_fail2.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_uniqueif.v");
 
-compile (
+compile(
     v_flags2 => ['+define+FAILING_ASSERTION2'],
     verilator_flags2 => ['--assert'],
     nc_flags2 => ['+assert'],
     fails => $Self->{nc},
     );
 
-execute (
+execute(
     fails => $Self->{vlt},
-    expect=>
+    expect =>
 '.*%Error: t_uniqueif.v:\d+: Assertion failed in top.t: \'unique if\' statement violated
 %Error: t/t_uniqueif.v:\d+: Verilog \$stop
 .*',
diff --git a/test_regress/t/t_uniqueif_fail3.pl b/test_regress/t/t_uniqueif_fail3.pl
index 43d8b0194..aa60344b8 100755
--- a/test_regress/t/t_uniqueif_fail3.pl
+++ b/test_regress/t/t_uniqueif_fail3.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_uniqueif.v");
 
-compile (
+compile(
     v_flags2 => ['+define+FAILING_ASSERTION3'],
     verilator_flags2 => ['--assert'],
     nc_flags2 => ['+assert'],
     fails => $Self->{nc},
     );
 
-execute (
+execute(
     fails => $Self->{vlt},
-    expect=>
+    expect =>
 '.*%Error: t_uniqueif.v:\d+: Assertion failed in top.t: \'unique if\' statement violated
 %Error: t/t_uniqueif.v:\d+: Verilog \$stop
 .*',
diff --git a/test_regress/t/t_uniqueif_fail4.pl b/test_regress/t/t_uniqueif_fail4.pl
index 29170b282..e6aa8eaa2 100755
--- a/test_regress/t/t_uniqueif_fail4.pl
+++ b/test_regress/t/t_uniqueif_fail4.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_uniqueif.v");
 
-compile (
+compile(
     v_flags2 => ['+define+FAILING_ASSERTION4'],
     verilator_flags2 => ['--assert'],
     nc_flags2 => ['+assert'],
     fails => $Self->{nc},
     );
 
-execute (
+execute(
     fails => $Self->{vlt},
-    expect=>
+    expect =>
 '.*%Error: t_uniqueif.v:\d+: Assertion failed in top.t: \'unique if\' statement violated
 %Error: t/t_uniqueif.v:\d+: Verilog \$stop
 .*',
diff --git a/test_regress/t/t_unopt_array.pl b/test_regress/t/t_unopt_array.pl
index d4d101b66..e9c629464 100755
--- a/test_regress/t/t_unopt_array.pl
+++ b/test_regress/t/t_unopt_array.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2=>["-Wno-UNOPTFLAT"],
     );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_unopt_array_csplit.pl b/test_regress/t/t_unopt_array_csplit.pl
index 42beadc2b..27ec9551f 100755
--- a/test_regress/t/t_unopt_array_csplit.pl
+++ b/test_regress/t/t_unopt_array_csplit.pl
@@ -7,15 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_unopt_array.v");
-compile (
+compile(
     v_flags2 => ["--trace --output-split 1 --output-split-cfuncs 1 -Wno-UNOPTFLAT"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_unopt_bound.pl b/test_regress/t/t_unopt_bound.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_unopt_bound.pl
+++ b/test_regress/t/t_unopt_bound.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_unopt_combo.pl b/test_regress/t/t_unopt_combo.pl
index 9da774c63..d8968a2c2 100755
--- a/test_regress/t/t_unopt_combo.pl
+++ b/test_regress/t/t_unopt_combo.pl
@@ -7,13 +7,15 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ['+define+ALLOW_UNOPT'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    v_flags2 => ['+define+ALLOW_UNOPT'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_unopt_combo_bad.pl b/test_regress/t/t_unopt_combo_bad.pl
index a5a4c3e20..d1bd76527 100755
--- a/test_regress/t/t_unopt_combo_bad.pl
+++ b/test_regress/t/t_unopt_combo_bad.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_unopt_combo.v");
 
-compile (
-	 fails=>$Self->{vlt},
-	 expect=>
+compile(
+    fails => $Self->{vlt},
+    expect =>
 '%Warning-UNOPTFLAT: t/t_unopt_combo.v:\d+: Signal unoptimizable: Feedback to clock or circular logic: t.c
 %Warning-UNOPTFLAT: Use "/\* verilator lint_off UNOPTFLAT \*/" and lint_on around source to disable this message.
 %Warning-UNOPTFLAT:      Example path: t/t_unopt_combo.v:\d+:  t.c
@@ -20,10 +22,10 @@ compile (
 %Warning-UNOPTFLAT:      Example path: t/t_unopt_combo.v:\d+:  ALWAYS
 %Warning-UNOPTFLAT:      Example path: t/t_unopt_combo.v:\d+:  t.c
 %Error: Exiting due to '
-	 );
+    );
 
-execute (
-     ) if !$Self->{vlt};
+execute(
+    ) if !$Self->{vlt};
 
 ok(1);
 1;
diff --git a/test_regress/t/t_unopt_combo_isolate.pl b/test_regress/t/t_unopt_combo_isolate.pl
index dd4b17130..1279cfb42 100755
--- a/test_regress/t/t_unopt_combo_isolate.pl
+++ b/test_regress/t/t_unopt_combo_isolate.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_unopt_combo.v");
 
-compile (
-	 verilator_flags2 => ['+define+ISOLATE --stats'],
-	 );
+compile(
+    verilator_flags2 => ['+define+ISOLATE --stats'],
+    );
 
 if ($Self->{vlt}) {
-    file_grep ($Self->{stats}, qr/Optimizations, isolate_assignments blocks\s+5/i);
+    file_grep($Self->{stats}, qr/Optimizations, isolate_assignments blocks\s+5/i);
 }
 
-execute (
-	 );
+execute(
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_unopt_converge_initial_run_bad.pl b/test_regress/t/t_unopt_converge_initial_run_bad.pl
index 497906511..b6ce226bf 100755
--- a/test_regress/t/t_unopt_converge_initial_run_bad.pl
+++ b/test_regress/t/t_unopt_converge_initial_run_bad.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_unopt_converge_initial.v");
 
-compile (
+compile(
     v_flags2 => ['+define+ALLOW_UNOPT'],
     );
 
-execute (
-    fails=>1,
-    expect=> '%Error: \S+:\d+: Verilated model didn\'t DC converge',
+execute(
+    fails => 1,
+    expect => '%Error: \S+:\d+: Verilated model didn\'t DC converge',
     ) if $Self->{vlt};
 
 ok(1);
diff --git a/test_regress/t/t_unopt_converge_print_bad.pl b/test_regress/t/t_unopt_converge_print_bad.pl
index 95340a4e7..98597ca0b 100755
--- a/test_regress/t/t_unopt_converge_print_bad.pl
+++ b/test_regress/t/t_unopt_converge_print_bad.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_unopt_converge.v");
 #$Self->{verilated_debug} = 1;
 
-compile (
-	 v_flags2 => ['+define+ALLOW_UNOPT'],
-	 make_flags => 'CPPFLAGS_ADD=-DVL_DEBUG',
-	 );
+compile(
+    v_flags2 => ['+define+ALLOW_UNOPT'],
+    make_flags => 'CPPFLAGS_ADD=-DVL_DEBUG',
+    );
 
-execute (
-	 fails=>1,
-	 expect=> '%Error: \S+:\d+: Verilated model didn\'t converge',
-     ) if $Self->{vlt};
+execute(
+    fails => 1,
+    expect => '%Error: \S+:\d+: Verilated model didn\'t converge',
+    ) if $Self->{vlt};
 
 ok(1);
 1;
diff --git a/test_regress/t/t_unopt_converge_run_bad.pl b/test_regress/t/t_unopt_converge_run_bad.pl
index 2fa20cfd1..380c08025 100755
--- a/test_regress/t/t_unopt_converge_run_bad.pl
+++ b/test_regress/t/t_unopt_converge_run_bad.pl
@@ -7,16 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_unopt_converge.v");
 
-compile (
-	 v_flags2 => ['+define+ALLOW_UNOPT'],
-	 );
+compile(
+    v_flags2 => ['+define+ALLOW_UNOPT'],
+    );
 
-execute (
-	 fails=>1,
-	 expect=> '%Error: \S+:\d+: Verilated model didn\'t converge',
-     ) if $Self->{vlt};
+execute(
+    fails => 1,
+    expect => '%Error: \S+:\d+: Verilated model didn\'t converge',
+    ) if $Self->{vlt};
 
 ok(1);
 1;
diff --git a/test_regress/t/t_unopt_converge_unopt_bad.pl b/test_regress/t/t_unopt_converge_unopt_bad.pl
index 916ac4713..517b15153 100755
--- a/test_regress/t/t_unopt_converge_unopt_bad.pl
+++ b/test_regress/t/t_unopt_converge_unopt_bad.pl
@@ -7,16 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 top_filename("t/t_unopt_converge.v");
 
-$Self->{vlt} or $Self->skip("Verilator only test");
-
-compile (
-	 fails=>1,
-	 expect=> '%Warning-UNOPT: t/t_unopt_converge.v:\d+: Signal unoptimizable: Feedback to public clock or circular logic: x
+compile(
+    fails => 1,
+    expect => '%Warning-UNOPT: t/t_unopt_converge.v:\d+: Signal unoptimizable: Feedback to public clock or circular logic: x
 .*
 %Error: Exiting due to '
-     );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_unoptflat_simple_2_bad.pl b/test_regress/t/t_unoptflat_simple_2_bad.pl
index e3db81c7e..6323be90f 100755
--- a/test_regress/t/t_unoptflat_simple_2_bad.pl
+++ b/test_regress/t/t_unoptflat_simple_2_bad.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_unoptflat_simple_2.v");
 
 # Compile only
-compile (
+compile(
     verilator_flags3 => [],
     verilator_flags2 => ["--report-unoptflat"],
     fails => 1,
-    expect=>
+    expect =>
 '.*%Warning-UNOPTFLAT:      Widest candidate vars to split:
 %Warning-UNOPTFLAT:           t/t_unoptflat_simple_2.v:\d+:  t.x, width 3, fanout \d+
 .*%Error: Exiting due to ',
diff --git a/test_regress/t/t_unoptflat_simple_3_bad.pl b/test_regress/t/t_unoptflat_simple_3_bad.pl
index 0c2bf1c5c..a16bb204b 100755
--- a/test_regress/t/t_unoptflat_simple_3_bad.pl
+++ b/test_regress/t/t_unoptflat_simple_3_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_unoptflat_simple_3.v");
 
 # Compile only
-compile (
+compile(
     fails => 1
     );
 
diff --git a/test_regress/t/t_unoptflat_simple_bad.pl b/test_regress/t/t_unoptflat_simple_bad.pl
index ab27f0d1b..179c80e5a 100755
--- a/test_regress/t/t_unoptflat_simple_bad.pl
+++ b/test_regress/t/t_unoptflat_simple_bad.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_unoptflat_simple.v");
 
 # Compile only
-compile (
+compile(
     fails => 1
     );
 
diff --git a/test_regress/t/t_unpacked_array_order.pl b/test_regress/t/t_unpacked_array_order.pl
index 814a9a3bb..89a4e77d9 100755
--- a/test_regress/t/t_unpacked_array_order.pl
+++ b/test_regress/t/t_unpacked_array_order.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-);
+scenarios(simulator => 1);
 
-execute (
-    check_finished=>1,
-);
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_unroll_complexcond.pl b/test_regress/t/t_unroll_complexcond.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_unroll_complexcond.pl
+++ b/test_regress/t/t_unroll_complexcond.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_unroll_forfor.pl b/test_regress/t/t_unroll_forfor.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_unroll_forfor.pl
+++ b/test_regress/t/t_unroll_forfor.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_unroll_genf.pl b/test_regress/t/t_unroll_genf.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_unroll_genf.pl
+++ b/test_regress/t/t_unroll_genf.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_unroll_signed.pl b/test_regress/t/t_unroll_signed.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_unroll_signed.pl
+++ b/test_regress/t/t_unroll_signed.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_vams_basic.pl b/test_regress/t/t_vams_basic.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_vams_basic.pl
+++ b/test_regress/t/t_vams_basic.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_vams_wreal.pl b/test_regress/t/t_vams_wreal.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_vams_wreal.pl
+++ b/test_regress/t/t_vams_wreal.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_assign_landr.pl b/test_regress/t/t_var_assign_landr.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_var_assign_landr.pl
+++ b/test_regress/t/t_var_assign_landr.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_var_bad_hide.pl b/test_regress/t/t_var_bad_hide.pl
index f6b7ad616..731d091d7 100755
--- a/test_regress/t/t_var_bad_hide.pl
+++ b/test_regress/t/t_var_bad_hide.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only -Wwarn-VARHIDDEN"],
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only -Wwarn-VARHIDDEN"],
+    fails => $Self->{vlt},
+    expect =>
 '%Warning-VARHIDDEN: t/t_var_bad_hide.v:\d+: Declaration of signal hides declaration in upper scope: top
 .*
 %Warning-VARHIDDEN: t/t_var_bad_hide.v:\d+: ... Location of original declaration
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_bad_hide2.pl b/test_regress/t/t_var_bad_hide2.pl
index 737577c6c..5c8578c4b 100755
--- a/test_regress/t/t_var_bad_hide2.pl
+++ b/test_regress/t/t_var_bad_hide2.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only -Wwarn-VARHIDDEN"],
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only -Wwarn-VARHIDDEN"],
+    fails => $Self->{vlt},
+    expect =>
 '%Warning-VARHIDDEN: t/t_var_bad_hide2.v:\d+: Declaration of signal hides declaration in upper scope: t
 %Warning-VARHIDDEN: t/t_var_bad_hide2.v:\d+: ... Location of original declaration
 .*
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_bad_sameas.pl b/test_regress/t/t_var_bad_sameas.pl
index bc2f9d763..474386b36 100755
--- a/test_regress/t/t_var_bad_sameas.pl
+++ b/test_regress/t/t_var_bad_sameas.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 '%Error: t/t_var_bad_sameas.v:\d+: Unsupported in C: Cell has the same name as variable: varfirst
 %Error: t/t_var_bad_sameas.v:\d+: ... Location of original declaration
 %Error: t/t_var_bad_sameas.v:\d+: Unsupported in C: Task has the same name as (variable|cell): varfirst
@@ -21,7 +23,7 @@ compile (
 %Error: t/t_var_bad_sameas.v:\d+: Unsupported in C: Cell has the same name as task: taskfirst
 %Error: t/t_var_bad_sameas.v:\d+: ... Location of original declaration
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_bad_sv.pl b/test_regress/t/t_var_bad_sv.pl
index 36ad3a1b5..d9fc51154 100755
--- a/test_regress/t/t_var_bad_sv.pl
+++ b/test_regress/t/t_var_bad_sv.pl
@@ -7,16 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>$Self->{v3},
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => $Self->{vlt},
+    expect =>
 '%Error: t/t_var_bad_sv.v:\d+: Unexpected "do": "do" is a SystemVerilog keyword misused as an identifier.
 %Error: t/t_var_bad_sv.v:\d+: Modify the Verilog-2001 code to avoid SV keywords, or use `begin_keywords or --language.
 %Error: t/t_var_bad_sv.v:\d+: Unexpected "do": "do" is a SystemVerilog keyword misused as an identifier.
 .*
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_const.pl b/test_regress/t/t_var_const.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_var_const.pl
+++ b/test_regress/t/t_var_const.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_const_bad.pl b/test_regress/t/t_var_const_bad.pl
index 9441b355c..0dc969173 100755
--- a/test_regress/t/t_var_const_bad.pl
+++ b/test_regress/t/t_var_const_bad.pl
@@ -7,12 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 v_flags2 => ["--lint-only"],
-	 fails=>1,
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only"],
+    fails => 1,
+    expect =>
 '%Error: t/t_var_const_bad.v:\d+: Assigning to const variable: five
 %Error: Exiting due to.*',
     );
diff --git a/test_regress/t/t_var_dotted_inl0.pl b/test_regress/t/t_var_dotted_inl0.pl
index fb835d676..73474fc47 100755
--- a/test_regress/t/t_var_dotted_inl0.pl
+++ b/test_regress/t/t_var_dotted_inl0.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_var_dotted.v");
 
-compile (
-	 v_flags2 => ['+define+NOUSE_INLINE',],
-	 );
+compile(
+    v_flags2 => ['+define+NOUSE_INLINE',],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_dotted_inl1.pl b/test_regress/t/t_var_dotted_inl1.pl
index 285dd50b6..2dca3e9a2 100755
--- a/test_regress/t/t_var_dotted_inl1.pl
+++ b/test_regress/t/t_var_dotted_inl1.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_var_dotted.v");
 
-compile (
-	 v_flags2 => ['+define+USE_INLINE',],
-	 );
+compile(
+    v_flags2 => ['+define+USE_INLINE',],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_dotted_inl2.pl b/test_regress/t/t_var_dotted_inl2.pl
index 10221950a..9d713d5ee 100755
--- a/test_regress/t/t_var_dotted_inl2.pl
+++ b/test_regress/t/t_var_dotted_inl2.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_var_dotted.v");
 
-compile (
-	 v_flags2 => ['+define+USE_INLINE_MID',],
-	 );
+compile(
+    v_flags2 => ['+define+USE_INLINE_MID',],
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_escape.pl b/test_regress/t/t_var_escape.pl
index 40047aea4..0c36855e8 100755
--- a/test_regress/t/t_var_escape.pl
+++ b/test_regress/t/t_var_escape.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 # Access is so we can dump waves
-	 v_flags2 => [$Self->{v3}?'-trace':' +access+rwc'],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-	 );
+compile(
+    # Access is so we can dump waves
+    v_flags2 => [$Self->{vlt}?'-trace':' +access+rwc'],
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 if ($Self->{vlt}) {
     file_grep     ("$Self->{obj_dir}/simx.vcd", qr/\$enddefinitions/x);
@@ -23,7 +25,7 @@ if ($Self->{vlt}) {
     file_grep     ("$Self->{obj_dir}/simx.vcd", qr/ other\.cyc /);
     file_grep     ("$Self->{obj_dir}/simx.vcd", qr/ module mod\.with_dot /);
     vcd_identical ("$Self->{obj_dir}/simx.vcd",
-		   "t/$Self->{name}.out");
+                   "t/$Self->{name}.out");
 }
 
 ok(1);
diff --git a/test_regress/t/t_var_in_assign.pl b/test_regress/t/t_var_in_assign.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_var_in_assign.pl
+++ b/test_regress/t/t_var_in_assign.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_in_assign_bad.pl b/test_regress/t/t_var_in_assign_bad.pl
index f57fc8450..798ea257b 100755
--- a/test_regress/t/t_var_in_assign_bad.pl
+++ b/test_regress/t/t_var_in_assign_bad.pl
@@ -7,17 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
-compile (
-	 v_flags2 => ["--lint-only --Mdir obj_lint_only"],
-	 fails=>1,
-	 expect=>
+compile(
+    v_flags2 => ["--lint-only --Mdir obj_lint_only"],
+    fails => 1,
+    expect =>
 '%Error-ASSIGNIN: t/t_var_in_assign_bad.v:\d+: Assigning to input variable: value
 %Error-ASSIGNIN: t/t_var_in_assign_bad.v:\d+: Assigning to input variable: valueSub
 %Error: Exiting due to.*',
     );
 
-(!-d "obj_lint_only") or $Self->error("%Error: lint-only shouldn't make output directory");
+(!-d "obj_lint_only") or error("%Error: lint-only shouldn't make output directory");
 ok(1);
 1;
diff --git a/test_regress/t/t_var_init.pl b/test_regress/t/t_var_init.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_var_init.pl
+++ b/test_regress/t/t_var_init.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_life.pl b/test_regress/t/t_var_life.pl
index 47d4211f0..8e4600cdd 100755
--- a/test_regress/t/t_var_life.pl
+++ b/test_regress/t/t_var_life.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2 => ["--stats"],
-	 );
+scenarios(simulator => 1);
+
+compile(
+    verilator_flags2 => ["--stats"],
+    );
 
 if ($Self->{vlt}) {
-    file_grep ($Self->{stats}, qr/Optimizations, Lifetime assign deletions\s+(\d+)/i, 4);
-    file_grep ($Self->{stats}, qr/Optimizations, Lifetime constant prop\s+(\d+)/i, 2);
+    file_grep($Self->{stats}, qr/Optimizations, Lifetime assign deletions\s+(\d+)/i, 4);
+    file_grep($Self->{stats}, qr/Optimizations, Lifetime constant prop\s+(\d+)/i, 2);
 }
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_local.pl b/test_regress/t/t_var_local.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_var_local.pl
+++ b/test_regress/t/t_var_local.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_nonamebegin.pl b/test_regress/t/t_var_nonamebegin.pl
index fea02309b..1c424c79c 100755
--- a/test_regress/t/t_var_nonamebegin.pl
+++ b/test_regress/t/t_var_nonamebegin.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ['-trace'],
     );
 
-execute (
-	 expect=>quotemeta(
+execute(
+    expect => quotemeta(
 'ingen: {mod}.genblk1 top.t.genblk1
 d3a: {mod}.d3nameda top.t.d3nameda
 b2: {mod} top.t
@@ -25,8 +27,8 @@ t2 {mod}.tsk top.t
     );
 
 if ($Self->{vlt}) {
-    vcd_identical ("$Self->{obj_dir}/simx.vcd",
-		   "t/$Self->{name}.out");
+    vcd_identical("$Self->{obj_dir}/simx.vcd",
+                  "t/$Self->{name}.out");
 }
 ok(1);
 1;
diff --git a/test_regress/t/t_var_notfound_bad.pl b/test_regress/t/t_var_notfound_bad.pl
index fb793da88..458a8d8e5 100755
--- a/test_regress/t/t_var_notfound_bad.pl
+++ b/test_regress/t/t_var_notfound_bad.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 '%Error: t/t_var_notfound_bad.v:\d+: Can\'t find definition of variable: nf
 %Error: t/t_var_notfound_bad.v:\d+: Can\'t find definition of \'subsubz\' in dotted scope/variable: sub.subsubz
 %Error:      Known scopes under \'sub\': subsub
@@ -17,7 +19,7 @@ compile (
 %Error: t/t_var_notfound_bad.v:\d+: Can\'t find definition of task/function: notask
 %Error: t/t_var_notfound_bad.v:\d+: Found definition of \'a_var\' as a VAR but expected a task/function
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_outoforder.pl b/test_regress/t/t_var_outoforder.pl
index 29bf04d49..b1acebe26 100755
--- a/test_regress/t/t_var_outoforder.pl
+++ b/test_regress/t/t_var_outoforder.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_overcmp.pl b/test_regress/t/t_var_overcmp.pl
index f91289753..89a4e77d9 100755
--- a/test_regress/t/t_var_overcmp.pl
+++ b/test_regress/t/t_var_overcmp.pl
@@ -7,11 +7,13 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_var_overwidth_bad.pl b/test_regress/t/t_var_overwidth_bad.pl
index 16a1b18c2..ae65608f2 100755
--- a/test_regress/t/t_var_overwidth_bad.pl
+++ b/test_regress/t/t_var_overwidth_bad.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     make_main => 0,
     verilator_flags2 => ["--exe $Self->{t_dir}/t_var_overwidth_bad.cpp"],
     );
 
-execute (
-    fails=>1,
-    expect=>
+execute(
+    fails => 1,
+    expect =>
 qr{%Error: unknown:0: Testbench C set input 'clk' to value that overflows what the signal's width can fit
 Aborting....*}
     );
diff --git a/test_regress/t/t_var_overzero.pl b/test_regress/t/t_var_overzero.pl
index 067f038a8..8477d8386 100755
--- a/test_regress/t/t_var_overzero.pl
+++ b/test_regress/t/t_var_overzero.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     verilator_flags2 => ["--x-initial fast"],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_var_pins_cc.pl b/test_regress/t/t_var_pins_cc.pl
index f37155e78..2ec1c5ae7 100755
--- a/test_regress/t/t_var_pins_cc.pl
+++ b/test_regress/t/t_var_pins_cc.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_var_pinsizes.v");
 
-compile (
-	 verilator_flags2 => ['-cc'],
-	 verilator_make_gcc => 0,
-	 );
+compile(
+    verilator_flags2 => ['-cc'],
+    verilator_make_gcc => 0,
+    );
 
 if ($Self->{vlt}) {
     file_grep ("$Self->{obj_dir}/Vt_var_pins_cc.h", qr/VL_IN8  \(i1,0,0\);/x);
diff --git a/test_regress/t/t_var_pins_sc1.pl b/test_regress/t/t_var_pins_sc1.pl
index cd42fa7d9..cd4079487 100755
--- a/test_regress/t/t_var_pins_sc1.pl
+++ b/test_regress/t/t_var_pins_sc1.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_var_pinsizes.v");
 
-compile (
-	 verilator_flags2 => ["-sc -pins-bv 1 --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
-	 make_main => 0,
-	 );
+compile(
+    verilator_flags2 => ["-sc -pins-bv 1 --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
+    make_main => 0,
+    );
 
 if ($Self->{vlt}) {
     file_grep ("$Self->{obj_dir}/$Self->{VM_PREFIX}.h", qr/sc_in<sc_bv<1>\s> \s+ i1;/x);
diff --git a/test_regress/t/t_var_pins_sc2.pl b/test_regress/t/t_var_pins_sc2.pl
index 9846c7174..a7091e0dd 100755
--- a/test_regress/t/t_var_pins_sc2.pl
+++ b/test_regress/t/t_var_pins_sc2.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_var_pinsizes.v");
 
-compile (
-	 verilator_flags2 => ["-sc -pins-bv 2 --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
-	 make_main => 0,
-	 );
+compile(
+    verilator_flags2 => ["-sc -pins-bv 2 --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
+    make_main => 0,
+    );
 
 if ($Self->{vlt}) {
     file_grep ("$Self->{obj_dir}/$Self->{VM_PREFIX}.h", qr/sc_in<bool> \s+ i1;/x);
diff --git a/test_regress/t/t_var_pins_sc32.pl b/test_regress/t/t_var_pins_sc32.pl
index 92976f474..4f1338a3c 100755
--- a/test_regress/t/t_var_pins_sc32.pl
+++ b/test_regress/t/t_var_pins_sc32.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_var_pinsizes.v");
 
-compile (
-	 verilator_flags2 => ["-sc -no-pins64 --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
-	 make_main => 0,
-	 );
+compile(
+    verilator_flags2 => ["-sc -no-pins64 --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
+    make_main => 0,
+    );
 
 if ($Self->{vlt}) {
     file_grep ("$Self->{obj_dir}/$Self->{VM_PREFIX}.h", qr/sc_in<bool> \s+ i1;/x);
diff --git a/test_regress/t/t_var_pins_sc64.pl b/test_regress/t/t_var_pins_sc64.pl
index f5d06e70f..401e56be1 100755
--- a/test_regress/t/t_var_pins_sc64.pl
+++ b/test_regress/t/t_var_pins_sc64.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_var_pinsizes.v");
 
-compile (
-	 verilator_flags2 => ["-sc -pins64 --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
-	 make_main => 0,
-	 );
+compile(
+    verilator_flags2 => ["-sc -pins64 --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
+    make_main => 0,
+    );
 
 if ($Self->{vlt}) {
     file_grep ("$Self->{obj_dir}/$Self->{VM_PREFIX}.h", qr/sc_in<bool> \s+ i1;/x);
diff --git a/test_regress/t/t_var_pins_sc_biguint.pl b/test_regress/t/t_var_pins_sc_biguint.pl
index 439abd874..5313eac05 100755
--- a/test_regress/t/t_var_pins_sc_biguint.pl
+++ b/test_regress/t/t_var_pins_sc_biguint.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_var_pinsizes.v");
 
-compile (
-	 verilator_flags2 => ["-sc --pins-sc-biguint --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
-	 make_main => 0,
-	 );
+compile(
+    verilator_flags2 => ["-sc --pins-sc-biguint --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
+    make_main => 0,
+    );
 
 if ($Self->{vlt}) {
     file_grep ("$Self->{obj_dir}/$Self->{VM_PREFIX}.h", qr/sc_in<bool> \s+ i1;/x);
diff --git a/test_regress/t/t_var_pins_sc_uint.pl b/test_regress/t/t_var_pins_sc_uint.pl
index 9c8146733..8646cd9f1 100755
--- a/test_regress/t/t_var_pins_sc_uint.pl
+++ b/test_regress/t/t_var_pins_sc_uint.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_var_pinsizes.v");
 
-compile (
-	 verilator_flags2 => ["-sc --pins-sc-uint --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
-	 make_main => 0,
-	 );
+compile(
+    verilator_flags2 => ["-sc --pins-sc-uint --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
+    make_main => 0,
+    );
 
 if ($Self->{vlt}) {
     file_grep ("$Self->{obj_dir}/$Self->{VM_PREFIX}.h", qr/sc_in<bool> \s+ i1;/x);
diff --git a/test_regress/t/t_var_pins_sc_uint_biguint.pl b/test_regress/t/t_var_pins_sc_uint_biguint.pl
index 258f3ba44..39b2455a2 100755
--- a/test_regress/t/t_var_pins_sc_uint_biguint.pl
+++ b/test_regress/t/t_var_pins_sc_uint_biguint.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_var_pinsizes.v");
 
-compile (
-	 verilator_flags2 => ["-sc --pins-sc-uint --pins-sc-biguint --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
-	 make_main => 0,
-	 );
+compile(
+    verilator_flags2 => ["-sc --pins-sc-uint --pins-sc-biguint --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
+    make_main => 0,
+    );
 
 if ($Self->{vlt}) {
     file_grep ("$Self->{obj_dir}/$Self->{VM_PREFIX}.h", qr/sc_in<bool> \s+ i1;/x);
diff --git a/test_regress/t/t_var_pins_scui.pl b/test_regress/t/t_var_pins_scui.pl
index 3c5408585..46fc561ed 100755
--- a/test_regress/t/t_var_pins_scui.pl
+++ b/test_regress/t/t_var_pins_scui.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt_all => 1);
 
 top_filename("t/t_var_pinsizes.v");
 
-compile (
-	 verilator_flags2 => ["-sc -pins-uint8 --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
-	 make_main => 0,
-	 );
+compile(
+    verilator_flags2 => ["-sc -pins-uint8 --trace --exe $Self->{t_dir}/t_var_pinsizes.cpp"],
+    make_main => 0,
+    );
 
 if ($Self->{vlt}) {
     file_grep ("$Self->{obj_dir}/$Self->{VM_PREFIX}.h", qr/sc_in<bool> \s+ i1;/x);
diff --git a/test_regress/t/t_var_port_bad.pl b/test_regress/t/t_var_port_bad.pl
index 9be596e69..e9f3c1e38 100755
--- a/test_regress/t/t_var_port_bad.pl
+++ b/test_regress/t/t_var_port_bad.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 fails=>1,
-	 expect=>
+scenarios(simulator => 1);
+
+compile(
+    fails => 1,
+    expect =>
 '%Error: t/t_var_port_bad.v:\d+: Input/output/inout does not appear in port list: b
 %Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_rsvd.pl b/test_regress/t/t_var_rsvd.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_var_rsvd.pl
+++ b/test_regress/t/t_var_rsvd.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_rsvd_bad.pl b/test_regress/t/t_var_rsvd_bad.pl
index 4f318565c..6a2e4a9fb 100755
--- a/test_regress/t/t_var_rsvd_bad.pl
+++ b/test_regress/t/t_var_rsvd_bad.pl
@@ -7,16 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 top_filename("t/t_var_rsvd_port.v");
 
-compile (
-	 fails=>$Self->{v3},
-	 expect=>
+compile(
+    fails => $Self->{vlt},
+    expect =>
 q{%Warning-SYMRSVDWORD: t/t_var_rsvd_port.v:\d+: Symbol matches C\+\+ keyword: 'bool'
 .*
 %Warning-SYMRSVDWORD: t/t_var_rsvd_port.v:\d+: Symbol matches C\+\+ keyword: 'switch'
 %Error: Exiting due to.*},
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_rsvd_port.pl b/test_regress/t/t_var_rsvd_port.pl
index 187aefc1a..816372e7e 100755
--- a/test_regress/t/t_var_rsvd_port.pl
+++ b/test_regress/t/t_var_rsvd_port.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 verilator_flags2=>["-Wno-SYMRSVDWORD"],
-	 );
+scenarios(simulator => 1);
+
+compile(
+    verilator_flags2=>["-Wno-SYMRSVDWORD"],
+    );
 
 execute();
 
diff --git a/test_regress/t/t_var_set_link.pl b/test_regress/t/t_var_set_link.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_var_set_link.pl
+++ b/test_regress/t/t_var_set_link.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_static.pl b/test_regress/t/t_var_static.pl
index 823ae5c9b..73c135498 100755
--- a/test_regress/t/t_var_static.pl
+++ b/test_regress/t/t_var_static.pl
@@ -7,13 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} and $Self->unsupported("Verilator unsupported, bug546");
+scenarios(simulator => 1);
+$Self->{vlt} and unsupported("Verilator unsupported, bug546");
 
-compile (
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_var_tieout.pl b/test_regress/t/t_var_tieout.pl
index 7058e622f..89a4e77d9 100755
--- a/test_regress/t/t_var_tieout.pl
+++ b/test_regress/t/t_var_tieout.pl
@@ -7,12 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1,
-     );
+compile(
+    );
+
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_types.pl b/test_regress/t/t_var_types.pl
index 3deae9536..2ac96a92f 100755
--- a/test_regress/t/t_var_types.pl
+++ b/test_regress/t/t_var_types.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 $Self->{verilated_randReset} = 1;  # allow checking if we initialize vars to zero only when needed
 
-compile (
-	 );
+compile(
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_types_bad.pl b/test_regress/t/t_var_types_bad.pl
index 795407c97..fb26beffd 100755
--- a/test_regress/t/t_var_types_bad.pl
+++ b/test_regress/t/t_var_types_bad.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 $Self->{verilated_randReset} = 1;  # allow checking if we initialize vars to zero only when needed
 
-compile (
-	 fails=>1,
-	 expect=>
+compile(
+    fails => 1,
+    expect =>
 '%Error: t/t_var_types_bad.v:\d+: Illegal bit or array select; type does not have a bit range, or bad dimension: type is bit
 .*%Error: t/t_var_types_bad.v:\d+: Illegal bit or array select; type does not have a bit range, or bad dimension: type is logic
 .*%Error: t/t_var_types_bad.v:\d+: Illegal bit or array select; type does not have a bit range, or bad dimension: type is logic
 .*%Error: t/t_var_types_bad.v:\d+: Illegal bit or array select; type does not have a bit range, or bad dimension: type is real
 .*%Error: t/t_var_types_bad.v:\d+: Illegal bit or array select; type does not have a bit range, or bad dimension: type is real
 .*%Error: Exiting due to.*',
-	 );
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_var_vec_sel.pl b/test_regress/t/t_var_vec_sel.pl
index 10dc9a1ff..0a3119351 100755
--- a/test_regress/t/t_var_vec_sel.pl
+++ b/test_regress/t/t_var_vec_sel.pl
@@ -7,9 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     v_flags2 => ["--lint-only"],
-    fails=>0,
+    fails => 0,
     verilator_make_gcc => 0,
     make_top_shell => 0,
     make_main => 0,
diff --git a/test_regress/t/t_var_xref_gen.pl b/test_regress/t/t_var_xref_gen.pl
index d0b997efb..1f7906aae 100755
--- a/test_regress/t/t_var_xref_gen.pl
+++ b/test_regress/t/t_var_xref_gen.pl
@@ -7,7 +7,9 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
      verilator_flags2 => ["--debug-check"],
     );
 
diff --git a/test_regress/t/t_verilated_all.pl b/test_regress/t/t_verilated_all.pl
index 5799c25a2..1e4721eb0 100755
--- a/test_regress/t/t_verilated_all.pl
+++ b/test_regress/t/t_verilated_all.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt => 1);
+
 my $root = "..";
 
-compile (
+compile(
     # Can't use --coverage and --savable together, so cheat and compile inline
     verilator_flags2 => ['--cc --coverage-toggle --coverage-line --coverage-user --trace --vpi $root/include/verilated_save.cpp'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 my %hit;
@@ -36,7 +38,7 @@ foreach my $dfile (glob("$Self->{obj_dir}/*.d")) {
 foreach my $file (sort keys %hit) {
     if (!$hit{$file}
         && $file !~ /_sc/) {
-        $Self->error("Include file not covered by t_verilated_all test: ",$file);
+        error("Include file not covered by t_verilated_all test: ",$file);
     }
 }
 
diff --git a/test_regress/t/t_verilated_all_newest.pl b/test_regress/t/t_verilated_all_newest.pl
index 6e4f5eb51..a763d7ab2 100755
--- a/test_regress/t/t_verilated_all_newest.pl
+++ b/test_regress/t/t_verilated_all_newest.pl
@@ -7,18 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt => 1);
+
 top_filename("t/t_verilated_all.v");
 
 my $root = "..";
 
-compile (
+compile(
     # Can't use --coverage and --savable together, so cheat and compile inline
     verilator_flags2 => ['--cc --coverage-toggle --coverage-line --coverage-user --trace --vpi $root/include/verilated_save.cpp'],
     make_flags => 'DRIVER_STD=newest',
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_verilated_all_oldest.pl b/test_regress/t/t_verilated_all_oldest.pl
index 4a539d114..131f80c6f 100755
--- a/test_regress/t/t_verilated_all_oldest.pl
+++ b/test_regress/t/t_verilated_all_oldest.pl
@@ -7,6 +7,8 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(dist => 1);
+
 # This test now does nothing, because using DRIVER_STD=oldest tends to blow up glibc.
 
 ok(1);
diff --git a/test_regress/t/t_verilated_debug.pl b/test_regress/t/t_verilated_debug.pl
index c364d3809..508e62ae0 100755
--- a/test_regress/t/t_verilated_debug.pl
+++ b/test_regress/t/t_verilated_debug.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(vlt_all => 1);
+
 $Self->{verilated_debug} = 1;
 
-compile (
+compile(
     verilator_flags2 => [],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(files_identical("$Self->{obj_dir}/vlt_sim.log", "t/$Self->{name}.out"));
diff --git a/test_regress/t/t_verilated_threaded.pl b/test_regress/t/t_verilated_threaded.pl
index c6585d885..a61548dbc 100755
--- a/test_regress/t/t_verilated_threaded.pl
+++ b/test_regress/t/t_verilated_threaded.pl
@@ -7,19 +7,20 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("No thread support") if !$Self->cfg_with_threaded;
+scenarios(simulator => 1);
+$Self->cfg_with_threaded or skip("No thread support");
 
 top_filename("t/t_verilated_all.v");
 
 my $root = "..";
 
-compile (
+compile(
     # Can't use --coverage and --savable together, so cheat and compile inline
     verilator_flags2 => ['--cc --coverage-toggle --coverage-line --coverage-user --trace --threads 1 --vpi $root/include/verilated_save.cpp'],
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_vgen.pl b/test_regress/t/t_vgen.pl
index 0ef1423e5..6ebbec5f2 100755
--- a/test_regress/t/t_vgen.pl
+++ b/test_regress/t/t_vgen.pl
@@ -7,20 +7,22 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-if (eval "use Bit::Vector; return 2;" != 2) { $Self->error("Please install Bit::Vector"); }
+scenarios(simulator => 1);
+
+if (eval "use Bit::Vector; return 2;" != 2) { error("Please install Bit::Vector"); }
 
 top_filename("$Self->{obj_dir}/vgen.v");
 
-$Self->run(cmd=>["./vgen.pl",
-		 "-o $Self->{top_filename}",
-                 #"--seed 0",
+run(cmd => ["./vgen.pl",
+            "-o $Self->{top_filename}",
+            #"--seed 0",
            ]);
 
-compile (
+compile(
     );
 
-execute (
-    check_finished=>1,
+execute(
+    check_finished => 1,
     );
 
 ok(1);
diff --git a/test_regress/t/t_vlcov_merge.pl b/test_regress/t/t_vlcov_merge.pl
index da25bdd87..6a0e57121 100755
--- a/test_regress/t/t_vlcov_merge.pl
+++ b/test_regress/t/t_vlcov_merge.pl
@@ -7,24 +7,22 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(dist => 1);
 
-$Self->run(cmd=>["../bin/verilator_coverage",
-                 "--write", "$Self->{obj_dir}/coverage.dat",
-                 "t/t_vlcov_data_a.dat",
-                 "t/t_vlcov_data_b.dat",
-                 "t/t_vlcov_data_c.dat",
-                 "t/t_vlcov_data_d.dat",
-           ],
-    );
+run(cmd => ["../bin/verilator_coverage",
+            "--write", "$Self->{obj_dir}/coverage.dat",
+            "t/t_vlcov_data_a.dat",
+            "t/t_vlcov_data_b.dat",
+            "t/t_vlcov_data_c.dat",
+            "t/t_vlcov_data_d.dat",
+    ]);
 
 # Older clib's didn't properly sort maps, but the coverage data doesn't
 # really care about ordering. So avoid false failures by sorting.
-$Self->run(cmd=>["sort",
-                 "$Self->{obj_dir}/coverage.dat",
-                 "> $Self->{obj_dir}/coverage-sort.dat",
-           ],
-    );
+run(cmd => ["sort",
+            "$Self->{obj_dir}/coverage.dat",
+            "> $Self->{obj_dir}/coverage-sort.dat",
+    ]);
 
 ok(files_identical("$Self->{obj_dir}/coverage-sort.dat", "t/$Self->{name}.out"));
 1;
diff --git a/test_regress/t/t_vlcov_rank.pl b/test_regress/t/t_vlcov_rank.pl
index c013fddab..9f5eefe72 100755
--- a/test_regress/t/t_vlcov_rank.pl
+++ b/test_regress/t/t_vlcov_rank.pl
@@ -7,17 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(dist => 1);
 
-$Self->run(cmd=>["../bin/verilator_coverage",
-                 "--rank",
-                 "t/t_vlcov_data_a.dat",
-                 "t/t_vlcov_data_b.dat",
-                 "t/t_vlcov_data_c.dat",
-                 "t/t_vlcov_data_d.dat",
-           ],
-           logfile=>"$Self->{obj_dir}/vlcov.log",
-           tee => 0,
+run(cmd => ["../bin/verilator_coverage",
+            "--rank",
+            "t/t_vlcov_data_a.dat",
+            "t/t_vlcov_data_b.dat",
+            "t/t_vlcov_data_c.dat",
+            "t/t_vlcov_data_d.dat",
+    ],
+    logfile => "$Self->{obj_dir}/vlcov.log",
+    tee => 0,
     );
+
 ok(files_identical("$Self->{obj_dir}/vlcov.log", "t/$Self->{name}.out"));
 1;
diff --git a/test_regress/t/t_vlcov_rewrite.pl b/test_regress/t/t_vlcov_rewrite.pl
index 4e175473b..d636c45a4 100755
--- a/test_regress/t/t_vlcov_rewrite.pl
+++ b/test_regress/t/t_vlcov_rewrite.pl
@@ -7,18 +7,18 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(dist => 1);
 
 foreach my $basename ("t_vlcov_data_a.dat",
-		      "t_vlcov_data_b.dat",
-		      "t_vlcov_data_c.dat",
-		      "t_vlcov_data_d.dat",
+                      "t_vlcov_data_b.dat",
+                      "t_vlcov_data_c.dat",
+                      "t_vlcov_data_d.dat",
     ) {
-    $Self->run(cmd=>["../bin/verilator_coverage",
-                     "t/${basename}",
-                     "--write", "$Self->{obj_dir}/${basename}"
-               ],
-               tee=>0,
+    run(cmd => ["../bin/verilator_coverage",
+                "t/${basename}",
+                "--write", "$Self->{obj_dir}/${basename}"
+        ],
+        tee => 0,
         );
     ok(files_identical("$Self->{obj_dir}/${basename}", "t/${basename}"));
 }
diff --git a/test_regress/t/t_vlt_warn.pl b/test_regress/t/t_vlt_warn.pl
index df822d44f..0888801bc 100755
--- a/test_regress/t/t_vlt_warn.pl
+++ b/test_regress/t/t_vlt_warn.pl
@@ -7,14 +7,14 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("Verilator only test") if !$Self->{vlt};
+scenarios(vlt => 1);
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_make_gcc => 0,
-	 v_flags2 => ["--lint-only t/t_vlt_warn.vlt"],
-	 );
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_make_gcc => 0,
+    v_flags2 => ["--lint-only t/t_vlt_warn.vlt"],
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_vpi_get.cpp b/test_regress/t/t_vpi_get.cpp
index e862d321d..4cd41d87a 100644
--- a/test_regress/t/t_vpi_get.cpp
+++ b/test_regress/t/t_vpi_get.cpp
@@ -46,6 +46,9 @@ using namespace std;
 
 unsigned int main_time = false;
 
+#define STRINGIFY(x) STRINGIFY2(x)
+#define STRINGIFY2(x) #x
+
 //======================================================================
 
 #define CHECK_RESULT_VH(got, exp) \
@@ -248,8 +251,8 @@ int main(int argc, char **argv, char **env) {
     Verilated::traceEverOn(true);
     VL_PRINTF("Enabling waves...\n");
     VerilatedVcdC* tfp = new VerilatedVcdC;
-    topp->trace (tfp, 99);
-    tfp->open ("obj_dir/t_vpi_var/simx.vcd");
+    topp->trace(tfp, 99);
+    tfp->open(STRINGIFY(TEST_OBJ_DIR) "/simx.vcd");
 #endif
 
     topp->eval();
diff --git a/test_regress/t/t_vpi_get.pl b/test_regress/t/t_vpi_get.pl
index 195facc86..893ef732c 100755
--- a/test_regress/t/t_vpi_get.pl
+++ b/test_regress/t/t_vpi_get.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("Known compiler limitation")
+scenarios(simulator => 1);
+
+skip("Known compiler limitation")
     if $Self->cxx_version =~ /\(GCC\) 4.4/;
 
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     verilator_flags2 => ["-CFLAGS '-DVL_DEBUG -ggdb' --exe --vpi --no-l2name $Self->{t_dir}/t_vpi_get.cpp"],
@@ -19,9 +21,9 @@ compile (
     v_flags2 => ["+define+USE_VPI_NOT_DPI"],
 );
 
-execute (
+execute(
     iv_pli => 1,
-    check_finished=>1
+    check_finished => 1
 );
 
 ok(1);
diff --git a/test_regress/t/t_vpi_memory.cpp b/test_regress/t/t_vpi_memory.cpp
index a6277a5b7..fe7ed580f 100644
--- a/test_regress/t/t_vpi_memory.cpp
+++ b/test_regress/t/t_vpi_memory.cpp
@@ -46,6 +46,9 @@ using namespace std;
 
 unsigned int main_time = false;
 
+#define STRINGIFY(x) STRINGIFY2(x)
+#define STRINGIFY2(x) #x
+
 //======================================================================
 
 #define CHECK_RESULT_VH(got, exp) \
@@ -231,8 +234,8 @@ int main(int argc, char **argv, char **env) {
     Verilated::traceEverOn(true);
     VL_PRINTF("Enabling waves...\n");
     VerilatedVcdC* tfp = new VerilatedVcdC;
-    topp->trace (tfp, 99);
-    tfp->open ("obj_dir/t_vpi_var/simx.vcd");
+    topp->trace(tfp, 99);
+    tfp->open(STRINGIFY(TEST_OBJ_DIR) "/simx.vcd");
 #endif
 
     topp->eval();
diff --git a/test_regress/t/t_vpi_memory.pl b/test_regress/t/t_vpi_memory.pl
index 6042b3b7d..4e1d4d3e6 100755
--- a/test_regress/t/t_vpi_memory.pl
+++ b/test_regress/t/t_vpi_memory.pl
@@ -7,10 +7,12 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->skip("Known compiler limitation")
+scenarios(simulator => 1);
+
+skip("Known compiler limitation")
     if $Self->cxx_version =~ /\(GCC\) 4.4/;
 
-compile (
+compile(
     make_top_shell => 0,
     make_main => 0,
     make_pli => 1,
@@ -19,9 +21,9 @@ compile (
     verilator_flags2 => ["-CFLAGS '-DVL_DEBUG -ggdb' --exe --vpi --no-l2name $Self->{t_dir}/t_vpi_memory.cpp"],
     );
 
-execute (
+execute(
     iv_pli => 1,
-    check_finished=>1
+    check_finished => 1
     );
 
 ok(1);
diff --git a/test_regress/t/t_vpi_sc.pl b/test_regress/t/t_vpi_sc.pl
index 13d5edfd0..bc9248d9f 100755
--- a/test_regress/t/t_vpi_sc.pl
+++ b/test_regress/t/t_vpi_sc.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
+scenarios(simulator => 1);
+
+compile(
     # Must not make shell/main or hides bug
     make_top_shell => 0,
     make_main => 0,
     verilator_flags2 => ["--exe --vpi --sc $Self->{t_dir}/t_vpi_sc.cpp"],
 );
 
-execute (
-    check_finished=>1
+execute(
+    check_finished => 1
 );
 
 ok(1);
diff --git a/test_regress/t/t_vpi_unimpl.cpp b/test_regress/t/t_vpi_unimpl.cpp
index 15c05eee9..8e19d6ef3 100644
--- a/test_regress/t/t_vpi_unimpl.cpp
+++ b/test_regress/t/t_vpi_unimpl.cpp
@@ -34,6 +34,9 @@
 unsigned int main_time = false;
 unsigned int callback_count = false;
 
+#define STRINGIFY(x) STRINGIFY2(x)
+#define STRINGIFY2(x) #x
+
 //======================================================================
 
 #define CHECK_RESULT_VH(got, exp) \
@@ -162,8 +165,8 @@ int main(int argc, char **argv, char **env) {
     Verilated::traceEverOn(true);
     VL_PRINTF("Enabling waves...\n");
     VerilatedVcdC* tfp = new VerilatedVcdC;
-    topp->trace (tfp, 99);
-    tfp->open ("obj_dir/t_vpi_var/simx.vcd");
+    topp->trace(tfp, 99);
+    tfp->open(STRINGIFY(TEST_OBJ_DIR) "/simx.vcd");
 #endif
 
     topp->eval();
diff --git a/test_regress/t/t_vpi_unimpl.pl b/test_regress/t/t_vpi_unimpl.pl
index 78c55b76d..0b01888b4 100755
--- a/test_regress/t/t_vpi_unimpl.pl
+++ b/test_regress/t/t_vpi_unimpl.pl
@@ -7,15 +7,17 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 verilator_flags2 => ["-CFLAGS '-DVL_DEBUG -ggdb' --exe --vpi --no-l2name $Self->{t_dir}/t_vpi_unimpl.cpp"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 check_finished=>1
-     );
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    verilator_flags2 => ["-CFLAGS '-DVL_DEBUG -ggdb' --exe --vpi --no-l2name $Self->{t_dir}/t_vpi_unimpl.cpp"],
+    );
+
+execute(
+    check_finished => 1
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_vpi_var.cpp b/test_regress/t/t_vpi_var.cpp
index 2b28a1d35..dd87ddcae 100644
--- a/test_regress/t/t_vpi_var.cpp
+++ b/test_regress/t/t_vpi_var.cpp
@@ -91,11 +91,14 @@ unsigned int callback_count_strs_max = 500;
 #define CHECK_RESULT_CSTR_STRIP(got, exp) \
     CHECK_RESULT_CSTR(got+strspn(got, " "), exp)
 
+#define STRINGIFY(x) STRINGIFY2(x)
+#define STRINGIFY2(x) #x
+
 int _mon_check_mcd() {
     PLI_INT32 status;
 
     PLI_UINT32 mcd;
-    PLI_BYTE8* filename = (PLI_BYTE8*)"obj_dir/t_vpi_var/mcd_open.tmp";
+    PLI_BYTE8* filename = (PLI_BYTE8*)(STRINGIFY(TEST_OBJ_DIR) "/mcd_open.tmp");
     mcd = vpi_mcd_open(filename);
     CHECK_RESULT_NZ(mcd);
 
@@ -622,8 +625,8 @@ int main(int argc, char **argv, char **env) {
     Verilated::traceEverOn(true);
     VL_PRINTF("Enabling waves...\n");
     VerilatedVcdC* tfp = new VerilatedVcdC;
-    topp->trace (tfp, 99);
-    tfp->open ("obj_dir/t_vpi_var/simx.vcd");
+    topp->trace(tfp, 99);
+    tfp->open(STRINGIFY(TEST_OBJ_DIR) "/simx.vcd");
 #endif
 
     topp->eval();
diff --git a/test_regress/t/t_vpi_var.pl b/test_regress/t/t_vpi_var.pl
index 750bced9a..48387ade3 100755
--- a/test_regress/t/t_vpi_var.pl
+++ b/test_regress/t/t_vpi_var.pl
@@ -7,21 +7,23 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-compile (
-	 make_top_shell => 0,
-	 make_main => 0,
-	 make_pli => 1,
-	 sim_time => 2100,
-	 iv_flags2 => ["-g2005-sv -D USE_VPI_NOT_DPI -DWAVES"],
-	 v_flags2 => ["+define+USE_VPI_NOT_DPI"],
-	 verilator_flags2 => ["-CFLAGS '-DVL_DEBUG -ggdb' --exe --vpi --no-l2name $Self->{t_dir}/t_vpi_var.cpp"],
-	 );
+scenarios(simulator => 1);
 
-execute (
-	 iv_pli => 1,
-	 check_finished=>1,
-         all_run_flags => ['+PLUS +INT=1234 +STRSTR']
-     );
+compile(
+    make_top_shell => 0,
+    make_main => 0,
+    make_pli => 1,
+    sim_time => 2100,
+    iv_flags2 => ["-g2005-sv -D USE_VPI_NOT_DPI -DWAVES"],
+    v_flags2 => ["+define+USE_VPI_NOT_DPI"],
+    verilator_flags2 => ["-CFLAGS '-DVL_DEBUG -ggdb' --exe --vpi --no-l2name $Self->{t_dir}/t_vpi_var.cpp"],
+    );
+
+execute(
+    iv_pli => 1,
+    check_finished => 1,
+    all_run_flags => ['+PLUS +INT=1234 +STRSTR']
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_wire_types.pl b/test_regress/t/t_wire_types.pl
index 3deae9536..2ac96a92f 100755
--- a/test_regress/t/t_wire_types.pl
+++ b/test_regress/t/t_wire_types.pl
@@ -7,14 +7,16 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
+scenarios(simulator => 1);
+
 $Self->{verilated_randReset} = 1;  # allow checking if we initialize vars to zero only when needed
 
-compile (
-	 );
+compile(
+    );
 
-execute (
-	 check_finished=>1,
-     );
+execute(
+    check_finished => 1,
+    );
 
 ok(1);
 1;
diff --git a/test_regress/t/t_xml_first.out b/test_regress/t/t_xml_first.out
index a8c29db29..76575f0ca 100644
--- a/test_regress/t/t_xml_first.out
+++ b/test_regress/t/t_xml_first.out
@@ -4,67 +4,68 @@
   <files>
     <file id="a" filename="AstRoot" language="1800-2017"/>
     <file id="b" filename="COMMAND_LINE" language="1800-2017"/>
+    <file id="e" filename="COMMAND_LINE_DEFINE" language="1800-2017"/>
     <file id="c" filename="INTERNAL_VERILATOR_DEFINE" language="1800-2017"/>
     <file id="d" filename="input.vc" language="1800-2017"/>
-    <file id="e" filename="t/t_xml_first.v" language="1800-2017"/>
+    <file id="f" filename="t/t_xml_first.v" language="1800-2017"/>
   </files>
   <netlist>
-    <module fl="e6" name="t" topModule="1">
-      <var fl="e12" name="clk" dtype_id="1"/>
-      <var fl="e13" name="d" dtype_id="2"/>
-      <var fl="e14" name="q" dtype_id="2"/>
-      <var fl="e16" name="between" dtype_id="2"/>
-      <instance fl="e18" name="cell1" defName="mod1">
-        <port fl="e18" name="q" direction="out" portIndex="1">
-          <varref fl="e18" name="between" dtype_id="2"/>
+    <module fl="f6" name="t" topModule="1">
+      <var fl="f12" name="clk" dtype_id="1"/>
+      <var fl="f13" name="d" dtype_id="2"/>
+      <var fl="f14" name="q" dtype_id="2"/>
+      <var fl="f16" name="between" dtype_id="2"/>
+      <instance fl="f18" name="cell1" defName="mod1">
+        <port fl="f18" name="q" direction="out" portIndex="1">
+          <varref fl="f18" name="between" dtype_id="2"/>
         </port>
-        <port fl="e21" name="clk" direction="in" portIndex="2">
-          <varref fl="e21" name="clk" dtype_id="1"/>
+        <port fl="f21" name="clk" direction="in" portIndex="2">
+          <varref fl="f21" name="clk" dtype_id="1"/>
         </port>
-        <port fl="e22" name="d" direction="in" portIndex="3">
-          <varref fl="e22" name="d" dtype_id="2"/>
+        <port fl="f22" name="d" direction="in" portIndex="3">
+          <varref fl="f22" name="d" dtype_id="2"/>
         </port>
       </instance>
-      <instance fl="e24" name="cell2" defName="mod2">
-        <port fl="e24" name="d" direction="in" portIndex="1">
-          <varref fl="e24" name="between" dtype_id="2"/>
+      <instance fl="f24" name="cell2" defName="mod2">
+        <port fl="f24" name="d" direction="in" portIndex="1">
+          <varref fl="f24" name="between" dtype_id="2"/>
         </port>
-        <port fl="e27" name="q" direction="out" portIndex="2">
-          <varref fl="e27" name="q" dtype_id="2"/>
+        <port fl="f27" name="q" direction="out" portIndex="2">
+          <varref fl="f27" name="q" dtype_id="2"/>
         </port>
-        <port fl="e29" name="clk" direction="in" portIndex="3">
-          <varref fl="e29" name="clk" dtype_id="1"/>
+        <port fl="f29" name="clk" direction="in" portIndex="3">
+          <varref fl="f29" name="clk" dtype_id="1"/>
         </port>
       </instance>
     </module>
-    <module fl="e33" name="mod1">
-      <var fl="e35" name="clk" dtype_id="1"/>
-      <var fl="e36" name="d" dtype_id="2"/>
-      <var fl="e37" name="q" dtype_id="2"/>
-      <always fl="e39">
-        <sentree fl="e39">
-          <senitem fl="e39" edgeType="POS">
-            <varref fl="e39" name="clk" dtype_id="1"/>
+    <module fl="f33" name="mod1">
+      <var fl="f35" name="clk" dtype_id="1"/>
+      <var fl="f36" name="d" dtype_id="2"/>
+      <var fl="f37" name="q" dtype_id="2"/>
+      <always fl="f39">
+        <sentree fl="f39">
+          <senitem fl="f39" edgeType="POS">
+            <varref fl="f39" name="clk" dtype_id="1"/>
           </senitem>
         </sentree>
-        <assigndly fl="e40" dtype_id="2">
-          <varref fl="e40" name="d" dtype_id="2"/>
-          <varref fl="e40" name="q" dtype_id="2"/>
+        <assigndly fl="f40" dtype_id="2">
+          <varref fl="f40" name="d" dtype_id="2"/>
+          <varref fl="f40" name="q" dtype_id="2"/>
         </assigndly>
       </always>
     </module>
-    <module fl="e44" name="mod2">
-      <var fl="e46" name="clk" dtype_id="1"/>
-      <var fl="e47" name="d" dtype_id="2"/>
-      <var fl="e48" name="q" dtype_id="2"/>
-      <contassign fl="e51" dtype_id="2">
-        <varref fl="e51" name="d" dtype_id="2"/>
-        <varref fl="e51" name="q" dtype_id="2"/>
+    <module fl="f44" name="mod2">
+      <var fl="f46" name="clk" dtype_id="1"/>
+      <var fl="f47" name="d" dtype_id="2"/>
+      <var fl="f48" name="q" dtype_id="2"/>
+      <contassign fl="f51" dtype_id="2">
+        <varref fl="f51" name="d" dtype_id="2"/>
+        <varref fl="f51" name="q" dtype_id="2"/>
       </contassign>
     </module>
     <typetable fl="a0">
-      <basicdtype  fl="e46" id="1" name="logic"/>
-      <basicdtype  fl="e13" id="2" name="logic" left="3" right="0"/>
+      <basicdtype  fl="f46" id="1" name="logic"/>
+      <basicdtype  fl="f13" id="2" name="logic" left="3" right="0"/>
     </typetable>
   </netlist>
 </verilator_xml>
diff --git a/test_regress/t/t_xml_first.pl b/test_regress/t/t_xml_first.pl
index a544448e5..8d800ff69 100755
--- a/test_regress/t/t_xml_first.pl
+++ b/test_regress/t/t_xml_first.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
 my $out_filename = "$Self->{obj_dir}/V$Self->{name}.xml";
 
-compile (
+compile(
     verilator_flags2 => ['--xml-only'],
     verilator_make_gcc => 0,
     );
diff --git a/test_regress/t/t_xml_tag.out b/test_regress/t/t_xml_tag.out
index 0edec2e4a..8ab36d6b3 100644
--- a/test_regress/t/t_xml_tag.out
+++ b/test_regress/t/t_xml_tag.out
@@ -4,38 +4,39 @@
   <files>
     <file id="a" filename="AstRoot" language="1800-2017"/>
     <file id="b" filename="COMMAND_LINE" language="1800-2017"/>
+    <file id="e" filename="COMMAND_LINE_DEFINE" language="1800-2017"/>
     <file id="c" filename="INTERNAL_VERILATOR_DEFINE" language="1800-2017"/>
     <file id="d" filename="input.vc" language="1800-2017"/>
-    <file id="e" filename="t/t_xml_tag.v" language="1800-2017"/>
+    <file id="f" filename="t/t_xml_tag.v" language="1800-2017"/>
   </files>
   <netlist>
-    <module fl="e6" name="m">
-      <var fl="e8" name="clk_ip" tag="clk_ip" dtype_id="1"/>
-      <var fl="e9" name="rst_ip" dtype_id="1"/>
-      <var fl="e10" name="foo_op" tag="foo_op" dtype_id="1"/>
-      <typedef fl="e14" name="my_struct" tag="my_struct" dtype_id="2"/>
-      <var fl="e23" name="this_struct" tag="this_struct" dtype_id="3"/>
+    <module fl="f6" name="m">
+      <var fl="f8" name="clk_ip" tag="clk_ip" dtype_id="1"/>
+      <var fl="f9" name="rst_ip" dtype_id="1"/>
+      <var fl="f10" name="foo_op" tag="foo_op" dtype_id="1"/>
+      <typedef fl="f14" name="my_struct" tag="my_struct" dtype_id="2"/>
+      <var fl="f23" name="this_struct" tag="this_struct" dtype_id="3"/>
     </module>
     <typetable fl="a0">
-      <basicdtype  fl="e23" id="4" name="logic" left="31" right="0"/>
-      <basicdtype  fl="e8" id="1" name="logic"/>
-      <structdtype fl="e14" id="2">
-        <memberdtype fl="e15" id="5" name="clk" tag="this is clk" sub_dtype_id="6"/>
-        <memberdtype fl="e16" id="7" name="k" sub_dtype_id="8"/>
-        <memberdtype fl="e17" id="9" name="enable" tag="enable" sub_dtype_id="10"/>
-        <memberdtype fl="e18" id="11" name="data" tag="data" sub_dtype_id="12"/>
+      <basicdtype  fl="f23" id="4" name="logic" left="31" right="0"/>
+      <basicdtype  fl="f8" id="1" name="logic"/>
+      <structdtype fl="f14" id="2">
+        <memberdtype fl="f15" id="5" name="clk" tag="this is clk" sub_dtype_id="6"/>
+        <memberdtype fl="f16" id="7" name="k" sub_dtype_id="8"/>
+        <memberdtype fl="f17" id="9" name="enable" tag="enable" sub_dtype_id="10"/>
+        <memberdtype fl="f18" id="11" name="data" tag="data" sub_dtype_id="12"/>
       </structdtype>
-      <basicdtype  fl="e15" id="6" name="logic"/>
-      <basicdtype  fl="e16" id="8" name="logic"/>
-      <basicdtype  fl="e17" id="10" name="logic"/>
-      <basicdtype  fl="e18" id="12" name="logic"/>
-      <unpackarraydtype fl="e23" id="3" sub_dtype_id="2">
-        <range fl="e23">
-          <const fl="e23" name="32'h1" dtype_id="4"/>
-          <const fl="e23" name="32'h0" dtype_id="4"/>
+      <basicdtype  fl="f15" id="6" name="logic"/>
+      <basicdtype  fl="f16" id="8" name="logic"/>
+      <basicdtype  fl="f17" id="10" name="logic"/>
+      <basicdtype  fl="f18" id="12" name="logic"/>
+      <unpackarraydtype fl="f23" id="3" sub_dtype_id="2">
+        <range fl="f23">
+          <const fl="f23" name="32'h1" dtype_id="4"/>
+          <const fl="f23" name="32'h0" dtype_id="4"/>
         </range>
       </unpackarraydtype>
-      <refdtype fl="e23" id="13" name="my_struct" sub_dtype_id="2"/>
+      <refdtype fl="f23" id="13" name="my_struct" sub_dtype_id="2"/>
     </typetable>
   </netlist>
 </verilator_xml>
diff --git a/test_regress/t/t_xml_tag.pl b/test_regress/t/t_xml_tag.pl
index 31b7a1d91..58526cc8e 100755
--- a/test_regress/t/t_xml_tag.pl
+++ b/test_regress/t/t_xml_tag.pl
@@ -7,11 +7,11 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-$Self->{vlt} or $Self->skip("Verilator only test");
+scenarios(vlt => 1);
 
 my $out_filename = "$Self->{obj_dir}/V$Self->{name}.xml";
 
-compile (
+compile(
     verilator_flags2 => ['--xml-only'],
     verilator_make_gcc => 0,
     );