Version bump

Commentary
Add support for assume property (#2531 )
2026-10-02 16:13:34 +02:00 · 2020-09-07 09:26:03 -04:00 · 2020-09-07 09:20:17 -04:00 · 2020-09-03 12:38:48 -04:00 · 2020-09-03 08:09:47 -04:00 · 2020-08-31 19:02:58 -04:00
1961 changed files with 39083 additions and 22476 deletions
@@ -104,7 +104,7 @@ SpacesInContainerLiterals: true
 SpacesInCStyleCastParentheses: false
 SpacesInParentheses: false
 SpacesInSquareBrackets: false
-Standard:        Cpp03
+Standard:        Cpp11
 TabWidth:        8
 UseTab:          Never
 ...
@@ -3,3 +3,4 @@ exclude_paths:
  - '.github/**'
  - 'ci/build_verilator.sh'
  - 'include/vltstd/**'
+  - 'nodist/fastcov.py'
@@ -1,5 +1,6 @@
 \#*
 .#*
+.nfs*
 *~
 *.tidy
 *.old
@@ -8,176 +8,138 @@

 version: ~> 1.0

-os: linux
 language: cpp
-cache: ccache
-
-env:
-  global:
-    - VERILATOR_CACHE=$HOME/verilator_cache
-    - VERILATOR_ROOT=$PWD
-    - VERILATOR_NUM_JOBS=$(echo `nproc` + 1 | bc)
-    - VERILATOR_CONFIG_FLAGS="--enable-maintainer-mode --enable-longtests"
-    - VERILATOR_AUTHOR_SITE=1

 cache:
  directories:
-    - $VERILATOR_CACHE
+    - $HOME/.ccache

-before_install:
-# Perl modules needed for testing
-# Not listing Bit::Vector as slow to install, and only skips one test
-  - touch temp.cpp ; g++ -E -dM -c temp.cpp | sort ; rm -rf temp.cpp
-  - yes yes | sudo cpan -fi Unix::Processors Parallel::Forker
-  - sudo apt-get install gdb gtkwave
-  - sudo apt-get install libgoogle-perftools-dev
-before_script:
-  - bash -x ci/build_vcddiff.sh
-  - bash -x ci/build_verilator.sh
-after_script:
-  - ccache -s
+env:
+  global:
+    - VERILATOR_ROOT=$TRAVIS_BUILD_DIR

+# The list and order of build stages
 stages:
-  - "Build Verilator"
-  - test
+  - build # Build Verilator
+  - test  # Run tests

+# Dump info about the environment for debugging
+before_install:
+  # To dump the script that Travis itself is executing, add 'cat $0' here
+  - cd "$TRAVIS_BUILD_DIR" # Skipping the git clone in later stages requires this
+  - export CCACHE_MAXSIZE=$(ci/travis-ccache-size.bash) # Set here after the 'cd'
+  - env | sort
+  - ls -lA .
+  - ls -lA bin
+  - g++ -E -dM -c -x c++ /dev/null | sort
+  - clang++ -E -dM -c -x c++ /dev/null | sort
+
+# Install all dependencies
+# We run twice to attempt on failure to recover from temp network problems
+install:
+  - ./ci/travis-install.bash || ./ci/travis-install.bash
+
+before_script:
+  # ccache maintenance
+  - ./ci/travis-ccache-maint.bash
+  # Don't produce core dumps (esp. on FreeBSD)
+  - ulimit -c 0
+  # On Focal, set the SystemC installation location
+  - |
+    if [ "$TRAVIS_DIST" = "focal" ] && [ "$M32" != "1" ]; then
+      export SYSTEMC_INCLUDE=/usr/include
+      export SYSTEMC_LIBDIR=/usr/lib/x86_64-linux-gnu
+    fi
+  # Override compiler for M32
+  - |
+    if [ "$M32" = "1" ]; then
+      export CC="$CC -m32"
+      export CXX="$CXX -m32"
+      unset M32 # verilated.mk actually references $(M32) so unset
+    fi
+
+before_cache:
+  - ccache -s -z
+
+# All jobs run the same script
+script: ./ci/travis-script.bash
+
+# Enumerate all the jobs
 jobs:
  include:
-    - if: type != cron
-      stage: "Build Verilator"
-      name: Build Verilator
-      compiler: gcc
-      script: echo "Done building Verilator"
-# Non-cron build will just run on whatever linux flavor we get
-    - if: type != cron
-      stage: test
-      name: Dist test
-      compiler: gcc
-      script: ci/test.sh dist
-    - if: type != cron
-      stage: test
-      name: Vlt test
-      compiler: gcc
-      script: ci/test.sh vlt
-    - if: type != cron
-      stage: test
-      name: Vltmt set 0 test
-      compiler: gcc
-      script: ci/test.sh vltmt0
-    - if: type != cron
-      stage: test
-      name: Vltmt set 1 test
-      compiler: gcc
-      script: ci/test.sh vltmt1
-# Cron builds try different OS/compiler combinations
-    - if: type = cron
-      stage: "Build Verilator"
-      name: Build xenial gcc Verilator
-      os: linux
-      dist: xenial
-      compiler: gcc
-      script: echo "Done building Verilator"
-    - if: type = cron
-      stage: test
-      name: Xenial gcc dist test
-      os: linux
-      dist: xenial
-      compiler: gcc
-      script: ci/test.sh dist
-    - if: type = cron
-      stage: test
-      name: Xenial gcc vlt test
-      os: linux
-      dist: xenial
-      compiler: gcc
-      script: ci/test.sh vlt
-    - if: type = cron
-      stage: test
-      name: Xenial gcc vltmt test
-      os: linux
-      dist: xenial
-      compiler: gcc
-      script: ci/test.sh vltmt
-    - if: type = cron
-      stage: "Build Verilator"
-      name: Build xenial clang Verilator
-      os: linux
-      dist: xenial
-      compiler: clang
-      script: echo "Done building Verilator"
-    - if: type = cron
-      stage: test
-      name: Xenial clang dist test
-      os: linux
-      dist: xenial
-      compiler: clang
-      script: ci/test.sh dist
-    - if: type = cron
-      stage: test
-      name: Xenial clang vlt test
-      os: linux
-      dist: xenial
-      compiler: clang
-      script: ci/test.sh vlt
-    - if: type = cron
-      stage: test
-      name: Xenial clang vltmt test
-      os: linux
-      dist: xenial
-      compiler: clang
-      script: ci/test.sh vltmt
-#    - if: type = cron
-#      stage: "Build Verilator"
-#      name: Build OSX gcc Verilator
-#      os: osx
-#      compiler: gcc
-#      script: echo "Done building Verilator"
-#    - if: type = cron
-#      stage: test
-#      name: OSX gcc dist test
-#      os: osx
-#      compiler: gcc
-#      script: ci/test.sh dist
-#    - if: type = cron
-#      stage: test
-#      name: OSX gcc vlt test
-#      os: osx
-#      compiler: gcc
-#      script: ci/test.sh vlt
-#    - if: type = cron
-#      stage: test
-#      name: OSX gcc vltmt test
-#      os: osx
-#      compiler: gcc
-#      script: ci/test.sh vltmt
-    - if: type = cron
-      stage: "Build Verilator"
-      name: Build trusty gcc Verilator
-      os: linux
-      dist: trusty
-      compiler: gcc
-      script: echo "Done building Verilator"
-    - if: type = cron
-      stage: test
-      name: Trusty gcc dist test
-      os: linux
-      dist: trusty
-      compiler: gcc
-      script: ci/test.sh dist
-    - if: type = cron
-      stage: test
-      name: Trusty gcc vlt test
-      os: linux
-      dist: trusty
-      compiler: gcc
-      script: ci/test.sh vlt
-    - if: type = cron
-      stage: test
-      os: linux
-      dist: trusty
-      name: Trusty gcc vltmt test
-      compiler: gcc
-      script: ci/test.sh vltmt
+    ############################################################################
+    # Jobs in the 'build' stage
+    ############################################################################
+    # GCC builds
+    - {stage: build, if: type  = cron, os: linux, dist: trusty, compiler: gcc,   workspaces: {create: {name: trusty-gcc,   paths: .}}}
+    - {stage: build, if: type  = cron, os: linux, dist: xenial, compiler: gcc,   workspaces: {create: {name: xenial-gcc,   paths: .}}}
+    - {stage: build, if: type  = cron, os: linux, dist: bionic, compiler: gcc,   workspaces: {create: {name: bionic-gcc,   paths: .}}}
+    - {stage: build,                   os: linux, dist: focal,  compiler: gcc,   workspaces: {create: {name: focal-gcc,    paths: .}}}
+    # Clang builds
+    - {stage: build, if: type  = cron, os: linux, dist: xenial, compiler: clang, workspaces: {create: {name: xenial-clang, paths: .}}}
+    - {stage: build,                   os: linux, dist: focal,  compiler: clang, workspaces: {create: {name: focal-clang,  paths: .}}}
+    # Coverage build
+    - {stage: build, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {create: {name: coverage,     paths: .}}, env: COVERAGE=1}
+    # 32-bit build
+    - {stage: build, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {create: {name: focal-gcc-m32, paths: .}}, env: M32=1}
+    # OS X build
+    - {stage: build, if: type  = cron, os: osx, osx_image: xcode11.6, compiler: clang, workspaces: {create: {name: osx-xcode11.6, paths: .}}}
+    # FreeBSD build
+    - {stage: build, if: type  = cron, os: freebsd, compiler: clang, workspaces: {create: {name: freebsd, paths: .}}}
+    ############################################################################
+    # Jobs in the 'test' stage
+    ############################################################################
+    # GCC tests
+    - {stage: test, if: type  = cron, os: linux, dist: trusty, compiler: gcc,   workspaces: {use: trusty-gcc},   git: {clone: false}, env: TESTS=dist-vlt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: trusty, compiler: gcc,   workspaces: {use: trusty-gcc},   git: {clone: false}, env: TESTS=dist-vlt-1}
+    - {stage: test, if: type  = cron, os: linux, dist: trusty, compiler: gcc,   workspaces: {use: trusty-gcc},   git: {clone: false}, env: TESTS=vltmt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: trusty, compiler: gcc,   workspaces: {use: trusty-gcc},   git: {clone: false}, env: TESTS=vltmt-1}
+    - {stage: test, if: type  = cron, os: linux, dist: xenial, compiler: gcc,   workspaces: {use: xenial-gcc},   git: {clone: false}, env: TESTS=dist-vlt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: xenial, compiler: gcc,   workspaces: {use: xenial-gcc},   git: {clone: false}, env: TESTS=dist-vlt-1}
+    - {stage: test, if: type  = cron, os: linux, dist: xenial, compiler: gcc,   workspaces: {use: xenial-gcc},   git: {clone: false}, env: TESTS=vltmt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: xenial, compiler: gcc,   workspaces: {use: xenial-gcc},   git: {clone: false}, env: TESTS=vltmt-1}
+    - {stage: test, if: type  = cron, os: linux, dist: bionic, compiler: gcc,   workspaces: {use: bionic-gcc},   git: {clone: false}, env: TESTS=dist-vlt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: bionic, compiler: gcc,   workspaces: {use: bionic-gcc},   git: {clone: false}, env: TESTS=dist-vlt-1}
+    - {stage: test, if: type  = cron, os: linux, dist: bionic, compiler: gcc,   workspaces: {use: bionic-gcc},   git: {clone: false}, env: TESTS=vltmt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: bionic, compiler: gcc,   workspaces: {use: bionic-gcc},   git: {clone: false}, env: TESTS=vltmt-1}
+    - {stage: test, if: type != cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: focal-gcc},    git: {clone: false}, env: TESTS=dist-vlt-0}
+    - {stage: test, if: type != cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: focal-gcc},    git: {clone: false}, env: TESTS=dist-vlt-1}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: focal-gcc},    git: {clone: false}, env: TESTS=vltmt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: focal-gcc},    git: {clone: false}, env: TESTS=vltmt-1}
+    # Clang tests
+    - {stage: test, if: type  = cron, os: linux, dist: xenial, compiler: clang, workspaces: {use: xenial-clang}, git: {clone: false}, env: TESTS=dist-vlt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: xenial, compiler: clang, workspaces: {use: xenial-clang}, git: {clone: false}, env: TESTS=dist-vlt-1}
+    - {stage: test, if: type  = cron, os: linux, dist: xenial, compiler: clang, workspaces: {use: xenial-clang}, git: {clone: false}, env: TESTS=vltmt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: xenial, compiler: clang, workspaces: {use: xenial-clang}, git: {clone: false}, env: TESTS=vltmt-1}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: clang, workspaces: {use: focal-clang},  git: {clone: false}, env: TESTS=dist-vlt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: clang, workspaces: {use: focal-clang},  git: {clone: false}, env: TESTS=dist-vlt-1}
+    - {stage: test, if: type != cron, os: linux, dist: focal,  compiler: clang, workspaces: {use: focal-clang},  git: {clone: false}, env: TESTS=vltmt-0}
+    - {stage: test, if: type != cron, os: linux, dist: focal,  compiler: clang, workspaces: {use: focal-clang},  git: {clone: false}, env: TESTS=vltmt-1}
+    # Coverage tests
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: coverage},     git: {clone: false}, env: TESTS=coverage-dist}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: coverage},     git: {clone: false}, env: TESTS=coverage-vlt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: coverage},     git: {clone: false}, env: TESTS=coverage-vlt-1}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: coverage},     git: {clone: false}, env: TESTS=coverage-vlt-2}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: coverage},     git: {clone: false}, env: TESTS=coverage-vlt-3}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: coverage},     git: {clone: false}, env: TESTS=coverage-vltmt-0}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: coverage},     git: {clone: false}, env: TESTS=coverage-vltmt-1}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: coverage},     git: {clone: false}, env: TESTS=coverage-vltmt-2}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: coverage},     git: {clone: false}, env: TESTS=coverage-vltmt-3}
+    # 32-bit tests
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: focal-gcc-m32}, git: {clone: false}, env: [M32=1, TESTS=dist-vlt-0]}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: focal-gcc-m32}, git: {clone: false}, env: [M32=1, TESTS=dist-vlt-1]}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: focal-gcc-m32}, git: {clone: false}, env: [M32=1, TESTS=vltmt-0]}
+    - {stage: test, if: type  = cron, os: linux, dist: focal,  compiler: gcc,   workspaces: {use: focal-gcc-m32}, git: {clone: false}, env: [M32=1, TESTS=vltmt-1]}
+    # OS X tests
+    - {stage: test, if: type  = cron, os: osx, osx_image: xcode11.6, compiler: clang, workspaces: {use: osx-xcode11.6},  git: {clone: false}, env: TESTS=dist-vlt-0}
+    - {stage: test, if: type  = cron, os: osx, osx_image: xcode11.6, compiler: clang, workspaces: {use: osx-xcode11.6},  git: {clone: false}, env: TESTS=dist-vlt-1}
+    - {stage: test, if: type  = cron, os: osx, osx_image: xcode11.6, compiler: clang, workspaces: {use: osx-xcode11.6},  git: {clone: false}, env: TESTS=vltmt-0}
+    - {stage: test, if: type  = cron, os: osx, osx_image: xcode11.6, compiler: clang, workspaces: {use: osx-xcode11.6},  git: {clone: false}, env: TESTS=vltmt-1}
+    # FreeBSD tests
+    - {stage: test, if: type  = cron, os: freebsd, compiler: clang, workspaces: {use: freebsd}, git: {clone: false}, env: TESTS=dist-vlt-0}
+    - {stage: test, if: type  = cron, os: freebsd, compiler: clang, workspaces: {use: freebsd}, git: {clone: false}, env: TESTS=dist-vlt-1}
+    - {stage: test, if: type  = cron, os: freebsd, compiler: clang, workspaces: {use: freebsd}, git: {clone: false}, env: TESTS=vltmt-0}
+    - {stage: test, if: type  = cron, os: freebsd, compiler: clang, workspaces: {use: freebsd}, git: {clone: false}, env: TESTS=vltmt-1}

 notifications:
  email:
@@ -45,6 +45,7 @@ src/Makefile$
 src/Makefile_obj$
 include/verilated.mk$
 test_regress/.gdbinit$
+codecov.yml
 config.cache$
 config.status$
 verilator\.log
@@ -89,7 +89,6 @@ datarootdir = @datarootdir@
 CFG_WITH_CCWARN = @CFG_WITH_CCWARN@
 CFG_WITH_DEFENV = @CFG_WITH_DEFENV@
 CFG_WITH_LONGTESTS = @CFG_WITH_LONGTESTS@
-CFG_WITH_THREADED = @CFG_WITH_THREADED@
 PACKAGE_VERSION = @PACKAGE_VERSION@

 #### End of system configuration section. ####
@@ -425,6 +424,9 @@ CPPCHECK_CPP = $(wildcard \
 CPPCHECK_H = $(wildcard \
 	$(srcdir)/include/*.h \
 	$(srcdir)/src/*.h )
+CPPCHECK_YL = $(wildcard \
+	$(srcdir)/src/*.y \
+	$(srcdir)/src/*.l )
 CPPCHECK = src/cppcheck_filtered
 CPPCHECK_FLAGS = --enable=all --inline-suppr \
 	--suppress=unusedScopedObject --suppress=cstyleCast --suppress=useInitializationList \
@@ -435,7 +437,7 @@ CPPCHECK_INC = -I$(srcdir)/include -I$(srcdir)/src/obj_dbg -I$(srcdir)/src

 cppcheck: $(CPPCHECK_DEP)
 %.cppcheck: %.cpp
-	$(CPPCHECK) $(CPPCHECK_FLAGS) -DVL_DEBUG=1 -DVL_CPPCHECK=1 $(CPPCHECK_INC) $<
+	$(CPPCHECK) $(CPPCHECK_FLAGS) -DVL_DEBUG=1 -DVL_CPPCHECK=1 -DVL_THREADED=1 $(CPPCHECK_INC) $<

 CLANGTIDY = clang-tidy
 CLANGTIDY_FLAGS = -config=''
@@ -462,7 +464,7 @@ CLANGFORMAT_FLAGS = -i
 clang-format:
 	@$(CLANGFORMAT) --version | egrep 10.0 > /dev/null \
 		|| echo "*** You are not using clang-format 10.0, indents may differ from master's ***"
-	$(CLANGFORMAT) $(CLANGFORMAT_FLAGS) $(CPPCHECK_CPP) $(CPPCHECK_H)
+	$(CLANGFORMAT) $(CLANGFORMAT_FLAGS) $(CPPCHECK_CPP) $(CPPCHECK_H) $(CPPCHECK_YL)

 ftp: info

@@ -543,9 +545,6 @@ dist-file-list:
 	@echo $(wildcard $(DISTFILES))
 	@echo "end-dist-file-list:";  # Scripts look for this

-print-cfg-with-threaded:
-	@echo $(CFG_WITH_THREADED)
-
 ######################################################################
 # Distributions

@@ -5,6 +5,7 @@ ifdef::env-github[]
 image:https://img.shields.io/badge/License-LGPL%20v3-blue.svg[license LGPLv3,link=https://www.gnu.org/licenses/lgpl-3.0]
 image:https://img.shields.io/badge/License-Artistic%202.0-0298c3.svg[license Artistic-2.0,link=https://opensource.org/licenses/Artistic-2.0]
 image:https://api.codacy.com/project/badge/Grade/fa78caa433c84a4ab9049c43e9debc6f[Code Quality,link=https://www.codacy.com/gh/verilator/verilator]
+image:https://codecov.io/gh/verilator/verilator/branch/master/graph/badge.svg[Coverage,link=https://codecov.io/gh/verilator/verilator]
 image:https://travis-ci.com/verilator/verilator.svg?branch=master[Build Status (Travis CI),link=https://travis-ci.com/verilator/verilator]
 endif::[]

@@ -20,9 +21,9 @@ endif::[]

 == Welcome to Verilator

-[cols="a,a",indent=0,frame="none"]
+[cols="a,a",indent=0,frame="none",grid="rows"]
 |===
-^.^| *Welcome to Verilator, the fastest Verilog HDL simulator.*
+^.^| *Welcome to Verilator, the fastest Verilog/SystemVerilog simulator.*
 +++ <br/> +++ &bullet; Accepts synthesizable Verilog or SystemVerilog
 +++ <br/> +++ &bullet; Performs lint code-quality checks
 +++ <br/> +++ &bullet; Compiles into multithreaded {cpp}, or SystemC
@@ -73,15 +74,15 @@ replacement for NC-Verilog, VCS or another commercial Verilog simulator, or
 if you are looking for a behavioral Verilog simulator e.g. for a quick
 class project (we recommend http://iverilog.icarus.com[Icarus Verilog] for
 this.)  However, if you are looking for a path to migrate SystemVerilog to
-{cpp} or SystemC, and your team is comfortable writing just a
-touch of {cpp} code, Verilator is the tool for you.
+{cpp} or SystemC, or your team is comfortable writing just a touch of {cpp}
+code, Verilator is the tool for you.

 == Performance

 Verilator does not simply convert Verilog HDL to {cpp} or SystemC.  Rather,
 Verilator compiles your code into a much faster optimized and optionally
 thread-partitioned model, which is in turn wrapped inside a
-{cpp}/SystemC/{cpp}-under-Python module.  The results are a compiled
+{cpp}/SystemC module.  The results are a compiled
 Verilog model that executes even on a single-thread over 10x faster than
 standalone SystemC, and on a single thread is about 100 times faster than
 interpreted Verilog simulators such as http://iverilog.icarus.com[Icarus
@@ -112,9 +113,11 @@ For more information:
 * https://verilator.org/verilator_doc.html[Verilator manual (HTML)],
 or https://verilator.org/verilator_doc.pdf[Verilator manual (PDF)]

+* https://github.com/verilator/verilator-announce[Subscribe to verilator announcements]
+
 * https://verilator.org/forum[Verilator forum]

-* https://verilator.org/issues[Verilator Issues]
+* https://verilator.org/issues[Verilator issues]

 == Support

@@ -156,6 +156,8 @@ verilator_coverage - Verilator coverage analyzer

    verilator_coverage  -write merged.dat -read <datafiles>...

+    verilator_coverage  -write-info merged.info -read <datafiles>...
+
 Verilator_coverage processes Verilator coverage reports.

 With --anotate, it reads the specified data file and generates annotated
@@ -224,8 +226,20 @@ Displays program version and exits.
 =item --write I<filename>

 Specifies the aggregate coverage results, summed across all the files,
-should be written to the given filename.  This is useful in scripts to
-combine many sequential runs into one master coverage file.
+should be written to the given filename in verilator_coverage data format.
+This is useful in scripts to combine many sequential runs into one master
+coverage file.
+
+=item --write-info I<filename.info>
+
+Specifies the aggregate coverage results, summed across all the files,
+should be written to the given filename in C<lcov> .info format.
+This may be used to use C<lcov> to aggregate or generate reports.
+
+The info format loses data compared to the Verilator coverage data format;
+the info will all forms of coverage converted to line style coverage, and
+if there are multiple coverage points on a single line, the minimum
+coverage across those points will be used to report coverage of the line.

 =back

@@ -277,7 +291,7 @@ Wilson Snyder <[email protected]>

 =head1 SEE ALSO

-C<verilator>
+C<verilator>, C<lcov>

 L<verilator_coverage --help> which is the source for this document.

@@ -1,19 +0,0 @@
-#!/bin/bash
-# DESCRIPTION: Verilator: Build script for vcddiff
-#
-# Copyright 2019 by Todd Strader. 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
-set -e
-
-# NB: it would be better to add this via a PPA
-
-TMP_DIR=$(mktemp -d)
-
-git -C "${TMP_DIR}" clone https://github.com/veripool/vcddiff
-VCDDIFF_DIR=${TMP_DIR}/vcddiff
-git -C "${VCDDIFF_DIR}" checkout 5112f88b7ba8818dce9dfb72619e64a1fc19542c
-make -C "${VCDDIFF_DIR}"
-sudo cp "${VCDDIFF_DIR}/vcddiff" /usr/local/bin
@@ -1,65 +0,0 @@
-#!/bin/bash
-# DESCRIPTION: Verilator: Travis CI build script
-#
-# Copyright 2019 by Todd Strader. 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
-#
-# This script builds and caches the Verilator binaries for Travis CI
-# (and possibly other CI platforms).  The Verilator CI system uses this
-# script, but other CI systems that depend on Verilator may also use
-# the script.
-# see: https://github.com/verilator/verilator_ext_tests/blob/master/.travis.yml
-# To use this script, either checkout Verilator as part of the CI build
-# process or add Verilator as a Git submodule.  Verilator tarballs can
-# not be used as the script relies on Git revisions for caching.
-set -e
-
-if [ -z "${VERILATOR_NUM_JOBS}" ]; then
-    VERILATOR_NUM_JOBS=$(nproc)
-fi
-
-# Caching would be simpler if we installed without VERILATOR_ROOT, but
-#   it's needed for driver.pl outside of the repo
-if [ -z "${VERILATOR_ROOT}" ]; then
-    echo "VERILATOR_ROOT not set"
-    exit -1
-fi
-
-if [ -z "${VERILATOR_CACHE}" ]; then
-    echo "VERILATOR_CACHE not set"
-    exit -1
-fi
-
-VERILATOR_REV=$(cd "${VERILATOR_ROOT}" && git rev-parse HEAD)
-echo "Found Verilator rev ${VERILATOR_REV}"
-
-CACHED_REV_FILE=${VERILATOR_CACHE}/.rev.txt
-
-if [[ ! -f "${CACHED_REV_FILE}" || \
-      $(< "${CACHED_REV_FILE}") != "${VERILATOR_REV}" ]]; then
-    echo "Building Verilator"
-
-    # Unsure why Travis monkies with the capitalization of the stage name, but it does
-    if [[ -n ${TRAVIS_BUILD_STAGE_NAME} && \
-         ${TRAVIS_BUILD_STAGE_NAME} != "Build verilator" ]]; then
-      echo "WARNING: Building Verilator in Travis build stage other than \"Build verilator\": ${TRAVIS_BUILD_STAGE_NAME}"
-    fi
-
-    cd "${VERILATOR_ROOT}"
-    autoconf && ./configure ${VERILATOR_CONFIG_FLAGS} && make -j ${VERILATOR_NUM_JOBS}
-    # Copy the Verilator build artifacts
-    mkdir -p "${VERILATOR_CACHE}"
-    rm -rf ${VERILATOR_CACHE}/*
-    cp bin/*bin* "${VERILATOR_CACHE}"
-    # Remember the Git revision
-    echo "${VERILATOR_REV}" > "${CACHED_REV_FILE}"
-else
-    echo "Using cached Verilator"
-    cd "${VERILATOR_ROOT}"
-    # Create include/verilated_config.h and maybe other things
-    autoconf && ./configure ${VERILATOR_CONFIG_FLAGS}
-    cp ${VERILATOR_CACHE}/* bin
-fi
@@ -6,44 +6,40 @@
 # Version 2.0.
 # SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0

-FROM ubuntu:18.04
+FROM ubuntu:20.04

 RUN apt-get update \
    && DEBIAN_FRONTEND=noninteractive \
       apt-get install --no-install-recommends -y \
-                        autoconf=2.69-11 \
-                        bc=1.07.1-2 \
-                        bison=2:3.0.4.dfsg-1build1 \
-                        build-essential=12.4ubuntu1 \
-                        ca-certificates=20180409 \
-                        cmake=3.10.2-1ubuntu2.18.04.1 \
-                        flex=2.6.4-6 \
-                        gdb=8.1-0ubuntu3.2 \
-                        gcc-6=6.5.0-2ubuntu1~18.04 \
-                        gcc-5=5.5.0-12ubuntu1 \
-                        gcc-4.8=4.8.5-4ubuntu8 \
-                        git=1:2.17.1-1ubuntu0.5 \
-                        gtkwave=3.3.86-1 \
-                        g++-6=6.5.0-2ubuntu1~18.04 \
-                        g++-5=5.5.0-12ubuntu1 \
-                        g++-4.8=4.8.5-4ubuntu8 \
-                        libfl2=2.6.4-6 \
-                        libfl-dev=2.6.4-6 \
-                        numactl=2.0.11-2.1ubuntu0.1 \
-                        perl=5.26.1-6ubuntu0.3 \
-                        python3=3.6.7-1~18.04 \
-                        wget=1.19.4-1ubuntu2.2 \
-                        zlibc=0.9k-4.3 \
-                        zlib1g=1:1.2.11.dfsg-0ubuntu2 \
-                        zlib1g-dev=1:1.2.11.dfsg-0ubuntu2 \
+                        autoconf \
+                        bc \
+                        bison \
+                        build-essential \
+                        ca-certificates \
+                        ccache \
+                        clang \
+                        cmake \
+                        flex \
+                        gdb \
+                        git \
+                        gtkwave \
+                        libfl2 \
+                        libfl-dev \
+                        libgoogle-perftools-dev \
+                        libsystemc \
+                        libsystemc-dev \
+                        numactl \
+                        perl \
+                        python3 \
+                        wget \
+                        zlibc \
+                        zlib1g \
+                        zlib1g-dev \
    && apt-get clean \
    && rm -rf /var/lib/apt/lists/*

 WORKDIR /tmp

-COPY build-systemc.sh /tmp/
-RUN ./build-systemc.sh
-
 RUN cpan install -fi Unix::Processors Parallel::Forker Bit::Vector

 RUN git clone https://github.com/veripool/vcddiff.git && \
@@ -55,4 +51,6 @@ COPY build.sh /tmp/build.sh

 ENV VERILATOR_AUTHOR_SITE=1

+WORKDIR /work
+
 ENTRYPOINT [ "/tmp/build.sh" ]
@@ -5,7 +5,7 @@ build. It uses the following parameters:

 * Source repository (default: https://github.com/verilator/verilator)
 * Source revision (default: master)
-* GCC version (4.8.5, 5.5.0, 6.5.0, 7.4.0, default: 7.4.0)
+* Compiler (GCC 9.3.0, clang 10.0.0, default: 9.3.0)

 The container is published as `verilator/verilator-buildenv` on
 https://hub.docker.com/repository/docker/verilator/verilator-buildenv[docker hub].
@@ -20,13 +20,13 @@ To also run tests:

 To change the compiler:

-    docker run -ti -e CC=gcc-4.8 -e CXX=g++-4.8 verilator/verilator-buildenv test
+    docker run -ti -e CC=clang-10 -e CXX=clang++-10 verilator/verilator-buildenv test

 The tests that involve gdb are not working due to security restrictions.
 To run those too:

 ....
-docker run -ti -v ${PWD}:/tmp/repo -e REPO=/tmp/repo -e REV=`git rev-parse --short HEAD` -e CC=gcc-4.8 -e CXX=g++-4.8 --cap-add=SYS_PTRACE --security-opt seccomp=unconfined verilator/verilator-buildenv test
+docker run -ti -e CC=clang-10 -e CXX=clang++-10 --cap-add=SYS_PTRACE --security-opt seccomp=unconfined verilator/verilator-buildenv test
 ....

 Rather then building using a remote git repository you may prefer to use a
@@ -1,30 +0,0 @@
-#!/bin/bash -e
-# DESCRIPTION: Build SystemC in Ubuntu 18.04 with  different g++/gcc
-#
-# Copyright 2020 by Stefan Wallentowitz. 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
-
-build_variant () {
-    version=$($1 --version | grep gcc | awk '{print $4}')
-    mkdir "/usr/local/systemc-2.3.3-gcc$version"
-    mkdir build
-    cd build
-    ../configure --prefix="/usr/local/systemc-2.3.3-gcc$version" CC="$1" CXX="$2" LD="$2"
-    make -j
-    make install
-    cd ..
-    rm -r build
-}
-
-wget https://www.accellera.org/images/downloads/standards/systemc/systemc-2.3.3.tar.gz
-tar -xzf systemc-2.3.3.tar.gz
-cd systemc-2.3.3
-build_variant gcc g++
-build_variant gcc-6 g++-6
-build_variant gcc-5 g++-5
-build_variant gcc-4.8 g++-4.8
-cd ..
-rm -r systemc-2.3.3*
@@ -12,12 +12,6 @@
 : "${CC:=gcc}"
 : "${CXX:=g++}"

-GCCVERSION=$(${CC} --version | grep gcc | awk '{print $4}')
-
-export SYSTEMC_INCLUDE="/usr/local/systemc-2.3.3-gcc${GCCVERSION}/include"
-export SYSTEMC_LIBDIR="/usr/local/systemc-2.3.3-gcc${GCCVERSION}/lib-linux64"
-export LD_LIBRARY_PATH=${SYSTEMC_LIBDIR}
-
 SRCS=$PWD/verilator

 git clone "$REPO" "$SRCS"
@@ -6,19 +6,20 @@
 # Version 2.0.
 # SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0

-FROM ubuntu:18.04
+FROM ubuntu:20.04

 RUN apt-get update \
+    && DEBIAN_FRONTEND=noninteractive \
    && apt-get install --no-install-recommends -y \
-                        autoconf=2.69-11 \
-                        bc=1.07.1-2 \
-                        bison=2:3.0.4.dfsg-1build1 \
-                        build-essential=12.4ubuntu1 \
-                        ca-certificates=20180409 \
+                        autoconf \
+                        bc \
+                        bison \
+                        build-essential \
+                        ca-certificates \
                        ccache \
-                        flex=2.6.4-6 \
+                        flex \
                        git \
-                        libfl-dev=2.6.4-6 \
+                        libfl-dev \
                        libgoogle-perftools-dev \
                        perl \
                        python3 \
@@ -1,34 +0,0 @@
-#!/bin/bash
-# DESCRIPTION: Verilator: Travis CI test script
-#
-# Copyright 2019 by Todd Strader. 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
-
-set -e
-
-export DRIVER_FLAGS='-j 0 --quiet --rerun'
-
-case $1 in
-    dist)
-        make -C test_regress SCENARIOS=--dist
-        ;;
-    vlt)
-        make -C test_regress SCENARIOS=--vlt
-        ;;
-    vltmt)
-        make -C test_regress SCENARIOS=--vltmt
-        ;;
-    vltmt0)
-        make -C test_regress SCENARIOS=--vltmt DRIVER_HASHSET=--hashset=0/2
-        ;;
-    vltmt1)
-        make -C test_regress SCENARIOS=--vltmt DRIVER_HASHSET=--hashset=1/2
-        ;;
-    *)
-    echo "Usage: test.sh (dist|vlt|vltmt)"
-    exit -1
-    ;;
-esac
@@ -0,0 +1,29 @@
+#!/usr/bin/env bash
+# DESCRIPTION: Verilator: Travis CI ccache maintenance
+#
+# Copyright 2020 by Geza Lore. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+#
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+################################################################################
+# This script is run in 'before_script', once ccache has been set up.
+################################################################################
+
+set -e
+set -x
+
+# Show version
+ccache --version
+
+# Flush ccache if requested in commit message
+COMMIT="${TRAVIS_PULL_REQUEST_SHA:-$TRAVIS_COMMIT}"
+if git log --format=%B -n 1 "$COMMIT" | grep -q -i '\[travis\s\+ccache\s\+clear\]'; then
+  echo "Flushing ccache due to commit message"
+  ccache -C
+fi
+
+# Dump stats, then zero stats
+ccache -s -z
@@ -0,0 +1,37 @@
+#!/usr/bin/env bash
+# DESCRIPTION: Verilator: Travis CI ccache sizer
+#
+# Copyright 2020 by Geza Lore. 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.
+#
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+################################################################################
+# This script computes the size of the ccache to be used for a job. We want the
+# ccache to be just big enough to be able to hold a whole build so a re-build
+# of the same does not miss in the cache due to capacity, but we don't want the
+# ccache too big as pulling it down from the network takes time, and it is
+# unlikely objects from much earlier builds would be useful.
+################################################################################
+
+fatal() {
+  echo "ERROR: $(basename "$0"): $1" >&2; exit 1;
+}
+
+if [ "$TRAVIS_BUILD_STAGE_NAME" = "build" ]; then
+  if [ "$COVERAGE" == 1 ]; then
+    echo "1024M"
+  else
+    echo "768M"
+  fi
+elif [ "$TRAVIS_BUILD_STAGE_NAME" = "test" ]; then
+  if [[ $TESTS == coverage-* ]]; then
+    echo "1536M"
+  else
+    echo "256M"
+  fi
+else
+  fatal "Unknown build stage: '$TRAVIS_BUILD_STAGE_NAME'"
+fi
@@ -0,0 +1,104 @@
+#!/usr/bin/env bash
+# DESCRIPTION: Verilator: Travis CI dependency install script
+#
+# Copyright 2020 by Geza Lore. 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.
+#
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+################################################################################
+# This script runs in the 'install' phase of all jobs, in all stages. We try to
+# minimize the time spent in this by selectively installing only the components
+# required by the particular build stage.
+################################################################################
+
+# Note that Travis runs "apt-get update" when "apt-get install" is used in the
+# .travis.yml file directly, but since we invoke it via this script, we need to
+# run it manually where requried, otherwise some packages cannot be found.
+
+set -e
+set -x
+
+fatal() {
+  echo "ERROR: $(basename "$0"): $1" >&2; exit 1;
+}
+
+if [ "$TRAVIS_OS_NAME" = "linux" ]; then
+  MAKE=make
+elif [ "$TRAVIS_OS_NAME" = "osx" ]; then
+  MAKE=make
+elif [ "$TRAVIS_OS_NAME" = "freebsd" ]; then
+  MAKE=gmake
+else
+  fatal "Unknown os: '$TRAVIS_OS_NAME'"
+fi
+
+install-vcddiff() {
+  TMP_DIR="$(mktemp -d)"
+  git clone https://github.com/veripool/vcddiff "$TMP_DIR"
+  git -C "${TMP_DIR}" checkout 5112f88b7ba8818dce9dfb72619e64a1fc19542c
+  "$MAKE" -C "${TMP_DIR}"
+  sudo cp "${TMP_DIR}/vcddiff" /usr/local/bin
+}
+
+if [ "$TRAVIS_BUILD_STAGE_NAME" = "build" ]; then
+  ##############################################################################
+  # Dependencies of jobs in the 'build' stage, i.e.: packages required to
+  # build Verilator
+
+  if [ "$TRAVIS_OS_NAME" = "linux" ]; then
+    sudo apt-get update
+    sudo apt-get install libfl-dev
+    sudo apt-get install libgoogle-perftools-dev
+    if [ "$COVERAGE" = 1 ]; then
+      yes yes | sudo cpan -fi Unix::Processors Parallel::Forker
+    fi
+    if [ "$M32" = 1 ]; then
+      sudo apt-get install gcc-multilib g++-multilib
+    fi
+  elif [ "$TRAVIS_OS_NAME" = "osx" ]; then
+    brew update
+    brew install ccache perl gperftools
+  elif [ "$TRAVIS_OS_NAME" = "freebsd" ]; then
+    sudo pkg install -y autoconf bison ccache gmake perl5
+  else
+    fatal "Unknown os: '$TRAVIS_OS_NAME'"
+  fi
+elif [ "$TRAVIS_BUILD_STAGE_NAME" = "test" ]; then
+  ##############################################################################
+  # Dependencies of jobs in the 'test' stage, i.e.: packages required to
+  # run the tests
+
+  if [ "$TRAVIS_OS_NAME" = "linux" ]; then
+    sudo apt-get update
+    sudo apt-get install gdb gtkwave lcov
+    if [ "$TRAVIS_DIST" = "focal" ]; then
+      sudo apt-get install libsystemc-dev
+    fi
+    if [ "$M32" = 1 ]; then
+      sudo apt-get install lib32z1-dev gcc-multilib g++-multilib
+    fi
+  elif [ "$TRAVIS_OS_NAME" = "osx" ]; then
+    brew update
+    # brew cask install gtkwave # fst2vcd hangs at launch, so don't bother
+    brew install ccache perl
+  elif [ "$TRAVIS_OS_NAME" = "freebsd" ]; then
+    # fst2vcd fails with "Could not open '<input file>', exiting."
+    sudo pkg install -y ccache gmake perl5 python3
+  else
+    fatal "Unknown os: '$TRAVIS_OS_NAME'"
+  fi
+  # Common installs
+  if [ "$TRAVIS_DIST" != "trusty" ]; then
+    TRAVIS_CPAN_REPO=https://cpan.org
+  fi
+  # Not listing Bit::Vector as slow to install, and only skips one test
+  yes yes | sudo cpan -M $TRAVIS_CPAN_REPO -fi Unix::Processors Parallel::Forker
+  install-vcddiff
+else
+  ##############################################################################
+  # Unknown build stage
+  fatal "Unknown build stage: '$TRAVIS_BUILD_STAGE_NAME'"
+fi
@@ -0,0 +1,134 @@
+#!/usr/bin/env bash
+# DESCRIPTION: Verilator: Travis CI main job script
+#
+# Copyright 2020 by Geza Lore. 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.
+#
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+
+################################################################################
+# This is the main script executed in the 'script' phase by all jobs. We use a
+# single script to keep the .travis.yml spec simple. We pass job parameters via
+# environment variables using 'env' keys. Having different 'env' keys in jobs
+# ensures they use different Travis build caches.
+################################################################################
+
+set -e
+set -x
+
+fatal() {
+  echo "ERROR: $(basename "$0"): $1" >&2; exit 1;
+}
+
+if [ "$TRAVIS_OS_NAME" = "linux" ]; then
+  export MAKE=make
+  NPROC=$(nproc)
+elif [ "$TRAVIS_OS_NAME" = "osx" ]; then
+  export MAKE=make
+  NPROC=$(sysctl -n hw.logicalcpu)
+elif [ "$TRAVIS_OS_NAME" = "freebsd" ]; then
+  export MAKE=gmake
+  NPROC=$(sysctl -n hw.ncpu)
+else
+  fatal "Unknown os: '$TRAVIS_OS_NAME'"
+fi
+
+if [ "$TRAVIS_BUILD_STAGE_NAME" = "build" ]; then
+  ##############################################################################
+  # Build verilator
+
+  if [ "$COVERAGE" != 1 ]; then
+    autoconf
+    ./configure --enable-longtests --enable-ccwarn
+    "$MAKE" -j "$NPROC" -k
+    if [ "$TRAVIS_OS_NAME" = "osx" ]; then
+      file bin/verilator_bin
+      file bin/verilator_bin_dbg
+      md5 bin/verilator_bin
+      md5 bin/verilator_bin_dbg
+      stat bin/verilator_bin
+      stat bin/verilator_bin_dbg
+    fi
+  else
+    nodist/code_coverage --stages 1-2
+  fi
+elif [ "$TRAVIS_BUILD_STAGE_NAME" = "test" ]; then
+  ##############################################################################
+  # Run tests
+
+  if [ "$TRAVIS_OS_NAME" = "osx" ]; then
+    export VERILATOR_TEST_NO_GDB=1 # Pain to get GDB to work on OS X
+    export VERILATOR_TEST_NO_GPROF=1 # Apple Clang has no -pg
+    # export PATH="/Applications/gtkwave.app/Contents/Resources/bin:$PATH" # fst2vcd
+    file bin/verilator_bin
+    file bin/verilator_bin_dbg
+    md5 bin/verilator_bin
+    md5 bin/verilator_bin_dbg
+    stat bin/verilator_bin
+    stat bin/verilator_bin_dbg
+    # For some reason, the dbg exe is corrupted by this point ('file' reports
+    # it as data rather than a Mach-O). Unclear if this is an OS X issue or
+    # one for Travis. Remove the file and re-link...
+    rm bin/verilator_bin_dbg
+    "$MAKE" -j "$NPROC" -k
+  elif [ "$TRAVIS_OS_NAME" = "freebsd" ]; then
+    export VERILATOR_TEST_NO_GDB=1 # Disable for now, ideally should run
+    export VERILATOR_TEST_NO_GPROF=1 # gprof is a bit different on FreeBSD, disable
+  fi
+
+  # Run the specified test
+  case $TESTS in
+    dist-vlt-0)
+      "$MAKE" -C test_regress SCENARIOS="--dist --vlt" DRIVER_HASHSET=--hashset=0/2
+      ;;
+    dist-vlt-1)
+      "$MAKE" -C test_regress SCENARIOS="--dist --vlt" DRIVER_HASHSET=--hashset=1/2
+      ;;
+    vltmt-0)
+      "$MAKE" -C test_regress SCENARIOS=--vltmt DRIVER_HASHSET=--hashset=0/2
+      ;;
+    vltmt-1)
+      "$MAKE" -C test_regress SCENARIOS=--vltmt DRIVER_HASHSET=--hashset=1/2
+      ;;
+    coverage-dist)
+      nodist/code_coverage --stages 3- --scenarios=--dist
+      ;;
+    coverage-vlt-0)
+      nodist/code_coverage --stages 3- --scenarios=--vlt --hashset=0/4
+      ;;
+    coverage-vlt-1)
+      nodist/code_coverage --stages 3- --scenarios=--vlt --hashset=1/4
+      ;;
+    coverage-vlt-2)
+      nodist/code_coverage --stages 3- --scenarios=--vlt --hashset=2/4
+      ;;
+    coverage-vlt-3)
+      nodist/code_coverage --stages 3- --scenarios=--vlt --hashset=3/4
+      ;;
+    coverage-vltmt-0)
+      nodist/code_coverage --stages 3- --scenarios=--vltmt --hashset=0/4
+      ;;
+    coverage-vltmt-1)
+      nodist/code_coverage --stages 3- --scenarios=--vltmt --hashset=1/4
+      ;;
+    coverage-vltmt-2)
+      nodist/code_coverage --stages 3- --scenarios=--vltmt --hashset=2/4
+      ;;
+    coverage-vltmt-3)
+      nodist/code_coverage --stages 3- --scenarios=--vltmt --hashset=3/4
+      ;;
+    *)
+      fatal "Unknown test: $TESTS"
+      ;;
+  esac
+  # Upload coverage data to codecov.io
+  if [[ $TESTS == coverage-* ]]; then
+    bash <(curl -s https://codecov.io/bash) -f nodist/obj_dir/coverage/app_total.info
+  fi
+else
+  ##############################################################################
+  # Unknown build stage
+  fatal "Unknown build stage: '$TRAVIS_BUILD_STAGE_NAME'"
+fi
@@ -0,0 +1,38 @@
+# DESCRIPTION: codecov.io config
+#
+# Copyright 2020-2020 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.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+####################
+# Validate:
+#  curl --data-binary @codecov.yml https://codecov.io/validate
+
+codecov:
+  require_ci_to_pass: no
+
+coverage:
+  precision: 2
+  round: down
+  range: "70...100"
+  ignore:
+    - "ci"
+    - "docs"
+    - "examples"
+    - "include/gtkwave"
+    - "include/vltstd"
+    - "test_regress"
+
+parsers:
+  gcov:
+    branch_detection:
+      conditional: yes
+      loop: yes
+      method: no
+      macro: no
+
+comment:
+  layout: "reach,diff,flags,tree"
+  behavior: default
+  require_changes: yes
@@ -7,16 +7,20 @@

 #AC_INIT([Verilator],[#.### YYYY-MM-DD])
 #AC_INIT([Verilator],[#.### devel])
-AC_INIT([Verilator],[4.034 2020-05-03],
+AC_INIT([Verilator],[4.100 2020-09-07],
        [https://verilator.org],
        [verilator],[https://verilator.org])
 # When releasing, also update header of Changes file
 # and commit using "devel release" or "Version bump" message
+# Then 'make maintainer-dist'

 AC_CONFIG_HEADER(src/config_build.h)
 AC_CONFIG_FILES(Makefile docs/Makefile src/Makefile src/Makefile_obj include/verilated.mk include/verilated_config.h verilator.pc verilator-config.cmake verilator-config-version.cmake)

+# Version
 AC_MSG_RESULT([configuring for $PACKAGE_STRING])
+PACKAGE_VERSION_NUMBER=`AS_ECHO("$PACKAGE_VERSION") | sed 's/ .*//g'`
+AC_SUBST(PACKAGE_VERSION_NUMBER)

 # Ignore automake flags passed by Ubuntu builds
 AC_ARG_ENABLE([dependency-tracking],
@@ -109,27 +113,11 @@ AC_ARG_ENABLE([longtests],
 AC_SUBST(CFG_WITH_LONGTESTS)
 AC_MSG_RESULT($CFG_WITH_LONGTESTS)

-# CFG_WITH_PREC11
-AC_MSG_CHECKING(whether allow pre-C++11)
-AC_ARG_ENABLE([prec11],
-              [AS_HELP_STRING([--enable-prec11],
-                              [enable pre-C++11 compilers for Verilator binary
-                               and Verilated makefiles])],
-              [case "${enableval}" in
-                yes) CFG_WITH_PREC11=yes ;;
-                no)  CFG_WITH_PREC11=no ;;
-                *)   AC_MSG_ERROR([bad value ${enableval} for --enable-prec11]) ;;
-               esac],
-              [CFG_WITH_PREC11=no;]
-              )
-AC_SUBST(CFG_WITH_PREC11)
-AC_MSG_RESULT($CFG_WITH_PREC11)
-
-# Compiler flags
-CFLAGS+=" -I${includedir}"
-CPPFLAGS+=" -I${includedir}"
-CXXFLAGS+=" -I${includedir}"
-LDFLAGS+=" -L${libdir}"
+# Compiler flags (ensure they are not empty to avoid configure defaults)
+CFLAGS+=" "
+CPPFLAGS+=" "
+CXXFLAGS+=" "
+LDFLAGS+=" "

 # Checks for programs.
 AC_PROG_CC
@@ -150,14 +138,20 @@ AC_PATH_PROG(PERL,perl)
 if test "x$PERL" = "x" ; then
   AC_MSG_ERROR([Cannot find "perl" in your PATH, please install it])
 fi
+
 AC_PATH_PROG(LEX,flex)
 if test "x$LEX" = "x" ; then
   AC_MSG_ERROR([Cannot find "flex" in your PATH, please install it])
 fi
+flex_version=$($LEX --version | head -1)
+AC_MSG_RESULT([$LEX --version = $flex_version])
+
 AC_PATH_PROG(YACC,bison)
 if test "x$YACC" = "x" ; then
   AC_MSG_ERROR([Cannot find "bison" in your PATH, please install it])
 fi
+bison_version=$($YACC --version | head -1)
+AC_MSG_RESULT([$YACC --version = $bison_version])

 AC_CHECK_PROG(OBJCACHE,ccache,ccache)
 if test "x$OBJCACHE" != "x" ; then
@@ -400,12 +394,17 @@ _MY_LDLIBS_CHECK_IFELSE(
   fi])
 AC_SUBST(CFG_LIBS)

-# Set CFG_WITH_THREADED if can support threading
-AC_MSG_CHECKING(whether $CXX supports Verilated threads)
-ACO_SAVE_CXXFLAGS="$CXXFLAGS"
-CXXFLAGS="$CXXFLAGS $CFG_CXXFLAGS_STD_NEWEST $CFG_CXXFLAGS_NO_UNUSED"
-AC_LINK_IFELSE(
-     [AC_LANG_PROGRAM([#include <thread>], [[ ]])],
+# Need C++11 at least
+#Alternative: AX_CXX_COMPILE_STDCXX([11])
+AC_DEFUN([_MY_CXX_CHECK_CXX_VER],
+   [# _MY_CXX_CHECK_CXX_VER(flag) -- Check if compiler runs C++11
+    # Set $_my_result
+    AC_LINK_IFELSE(
+     [AC_LANG_PROGRAM([#include <thread>
+#if (__cplusplus < 201103L)
+# error "Too old"
+#endif
+    ], [[ ]])],
     [_my_result=yes
      if test -s conftest.err; then
        if grep -e "$1" conftest.err >/dev/null; then
@@ -413,24 +412,24 @@ AC_LINK_IFELSE(
        fi
      fi],
     [_my_result=no])
-CFG_WITH_THREADED=$_my_result
-AC_SUBST(CFG_WITH_THREADED)
-AC_MSG_RESULT($CFG_WITH_THREADED)
+   ])

-# Check compiler flag
-if test "$CFG_WITH_THREADED" = "no" ; then
-   if test "$CFG_WITH_PREC11" = "no" ; then
-      AC_MSG_NOTICE([[]])
-      AC_MSG_ERROR([[the $CXX compiler appears to not support C++11.
+AC_MSG_CHECKING(whether $CXX supports C++11)
+_MY_CXX_CHECK_CXX_VER()
+AC_MSG_RESULT($_my_result)
+if test "$_my_result" = "no" ; then
+   CXXFLAGS="$CXXFLAGS $CFG_CXXFLAGS_STD_NEWEST"
+   CFG_CXX_FLAGS_CMAKE="$CFG_CXX_FLAGS_CMAKE $CFG_CXXFLAGS_STD_NEWEST"
+   AC_MSG_CHECKING(whether $CXX supports C++11 with $CFG_CXXFLAGS_STD_NEWEST)
+   _MY_CXX_CHECK_CXX_VER()
+   AC_MSG_RESULT($_my_result)
+fi
+if test "$_my_result" = "no" ; then
+   AC_MSG_NOTICE([[]])
+   AC_MSG_ERROR([[the $CXX compiler appears to not support C++11.

-Verilator plans to require a C++11 or newer compiler in a future release,
-unless sufficient people report problems. Therefore, if you do not have a
-C++11 compiler, please post a message to
-https://www.veripool.org/boards/3/topics/2580-Verilator-Requiring-C-11-compiler
-indicating your OS and when you think C++11 might be ok, and then rerun
-configure with the --enable-prec11 argument. Thanks.]])
+Verilator requires a C++11 or newer compiler.]])

-   fi
 fi

 # Checks for library functions.
@@ -438,6 +437,24 @@ AC_CHECK_MEMBER([struct stat.st_mtim.tv_nsec],
    [AC_DEFINE([HAVE_STAT_NSEC],[1],[Defined if struct stat has st_mtim.tv_nsec])],
    [], [#include <sys/stat.h>])

+# HAVE_SYSTEMC
+# - If found the default search path has it, so support is always enabled.
+# - If not found or not system-wide, user can set SYSTEMC_INCLUDE.
+# AC_CHECK_HEADERS seems to not locate on Travis-CI but include does work.
+AC_MSG_CHECKING([whether SystemC is found (in system path)])
+ACO_SAVE_LIBS="$LIBS"
+LIBS="$LIBS -lsystemc"
+AC_LINK_IFELSE(
+    [AC_LANG_PROGRAM([[#include <systemc.h>
+                     extern "C" int sc_main(int argc, char* argv[]) {}
+                     ]],[[sc_version()]])],
+    [_my_result=yes
+     AC_DEFINE([HAVE_SYSTEMC],[1],[Defined if have SystemC library])],
+    [_my_result=no])
+AC_MSG_RESULT($_my_result)
+LIBS="$ACO_SAVE_LIBS"
+AC_SUBST(HAVE_SYSTEMC)
+
 # Checks for system services

 # Other install directories
@@ -6,27 +6,42 @@ Please see the Verilator manual for 200+ additional contributors. Thanks to all.
 Ahmed El-Mahmoudy
 Alex Chadwick
 Chris Randall
+Conor McCullough
+Dan Petrisko
+David Horton
 David Stanford
 Driss Hafdi
+Edgar E. Iglesias
 Eric Rippey
+Fan Shupei
 Garrett Smith
 Geza Lore
 Gianfranco Costamagna
+Glen Gibb
+Harald Heckmann
 Howard Su
+Huang Rui
 Iztok Jeras
 James Hanlon
+James Hutchinson
+Jamey Hicks
+Jan Van Winkel
 Jeremy Bennett
 John Coiner
 John Demme
+Josh Redford
 Julien Margetts
 Kanad Kanhere
 Kevin Kiningham
 Kuba Ober
+Ludwig Rogiers
 Lukasz Dalek
 Maarten De Braekeleer
 Maciej Sobkowski
 Marco Widmer
+Marshal Qiao
 Matthew Ballance
+Michael Killough
 Mike Popoloski
 Nathan Kohagen
 Nathan Myers
@@ -35,15 +50,25 @@ Peter Horvath
 Peter Monsson
 Philipp Wagner
 Pieter Kapsenberg
+Piotr Binkowski
 Qingyao Sun
 Richard Myers
+Rupert Swarbrick
 Sean Cross
 Sebastien Van Cauwenberghe
+Sergi Granell
 Stefan Wallentowitz
+Stephen Henry
+Tim Snyder
 Tobias Rosenkranz
 Tobias Wölfel
 Todd Strader
+Tomasz Gorochowik
+Tymoteusz Blazejczyk
+Vassilis Papaefstathiou
 Veripool API Bot
 Wilson Snyder
+Yossi Nivin
+Yuri Victorovich
 Yutetsu TAKATSUKASA
 Yves Mathieu
@@ -39,7 +39,7 @@ brief:
 #sudo apt-get install libfl2  # Ubuntu only (ignore if gives error)
 #sudo apt-get install libfl-dev  # Ubuntu only (ignore if gives error)

-git clone https://git.veripool.org/git/verilator   # Only first time
+git clone https://github.com/verilator/verilator   # Only first time
 ## Note the URL above is not a page you can see with a browser, it's for git only

 # Every time you need to build:
@@ -69,19 +69,18 @@ Linux distribution, see instead <<Install From a Package Manager>>.

 === OS Requirements

-Verilator is developed and has primary testing on Ubuntu.  Versions have
-also built on Redhat Linux, Apple OS-X, HPUX and Solaris.  It should run
-with minor porting on any GNU/Linux-ish platform.  Verilator also works on
-Windows under Cygwin, and Windows under MinGW (gcc -mno-cygwin).  Verilated
-output (not Verilator itself) compiles under all the options above, plus
-MSVC++.
+Verilator is developed and has primary testing on Ubuntu, with additional
+testing on FreeBSD and Apple OS-X.  Versions have also built on Redhat
+Linux, HPUX and Solaris.  It should run with minor porting on any
+GNU/Linux-ish platform.  Verilator also works on Windows under Cygwin, and
+Windows under MinGW (gcc -mno-cygwin).  Verilated output (not Verilator
+itself) compiles under all the options above, plus MSVC++.

 === Install Prerequisites

 To build or run Verilator you need these standard packages:

-   sudo apt-get install perl python3
-   sudo apt-get install make
+   sudo apt-get install perl python3 make
   sudo apt-get install g++  # Alternatively, clang
   sudo apt-get install libgz  # Non-Ubuntu (ignore if gives error)
   sudo apt-get install libfl2 libfl-dev zlibc zlib1g zlib1g-dev  # Ubuntu only (ignore if gives error)
@@ -90,17 +89,16 @@ To build or run the following are optional but should be installed for
 good performance:

   sudo apt-get install ccache  # If present at build, needed for run
-   sudo apt-get install libgoogle-perftools-dev numactl
+   sudo apt-get install libgoogle-perftools-dev numactl perl-doc

 To build Verilator you will need to install these packages; these do not
 need to be present to run Verilator:

-   sudo apt-get install git
-   sudo apt-get install autoconf flex bison
+   sudo apt-get install git autoconf flex bison

 Those developing Verilator itself may also want these (see internals.adoc):

-   sudo apt-get install gdb asciidoctor graphviz cmake clang-format
+   sudo apt-get install gdb asciidoctor graphviz cmake clang clang-format gprof lcov
   cpan install Pod::Perldoc
   cpan install Unix::Processors
   cpan install Parallel::Forker
@@ -130,7 +128,7 @@ Downloads]; we presume you know how to use it, and is not described here.)

 Get the sources from the repository: (You need do this only once, ever.)

-   git clone https://git.veripool.org/git/verilator   # Only first time
+   git clone https://github.com/verilator/verilator   # Only first time
   ## Note the URL above is not a page you can see with a browser, it's for git only

 Enter the checkout and determine what version/branch to use:
@@ -266,10 +264,9 @@ set in your environment; it is built into the executable.

 == Announcements

-To get notified of new releases, login to
-https://www.veripool.org[Veripool], and click the "watch" button near the
-top right under https://www.veripool.org/projects/verilator/news[Verilator
-News].
+To get notified of new releases, go to
+https://github.com/verilator/verilator-announce[Verilator announcement
+repository] and follow the instructions there.

 == Directory Structure

@@ -387,10 +387,8 @@ changed; if clear, checking those signals for changes may be skipped.

 === Compiler Version and C++11

-Verilator supports GCC 4.4.7 and newer.  GCC 4.4.7 does not support C++11,
-therefore C++11 is generally not required.  Exceptions may be made to
-require C++11 for features that are only practical with C++11,
-e.g. threads.
+Verilator requires C++11. Verilator does not require any newer versions,
+but is maintained to build successfully with C++14/C++17/C++20.

 === Indentation and Naming Style

@@ -777,19 +775,20 @@ output, for example:
 You can then print a.ps.  You may prefer gif format, which doesn't get
 scaled so can be more useful with large graphs.

-For dynamic graph viewing consider
+For interactive graph viewing consider
+https://github.com/jrfonseca/xdot.py[xdot] or
 http://zvtm.sourceforge.net/zgrviewer.html[ZGRViewer].  If you know of
-better viewers let us know; ZGRViewer isn't great for large graphs.
+better viewers (especially for large graphs) please let us know.

 === .tree Output

 Tree files are dumps of the AST Tree and are produced between every major
 algorithmic stage.  An example:

-     NETLIST 0x90fb00 <e1> {a0}
-    1: MODULE 0x912b20 <e8822> {a8}  top  L2 [P]
-   *1:2: VAR 0x91a780 <e74#> {a22} @dt=0xa2e640(w32)  out_wide [O] WIRE
-    1:2:1: BASICDTYPE 0xa2e640 <e2149> {e24} @dt=this(sw32)  integer kwd=integer range=[31:0]
+     NETLIST 0x90fb00 <e1> {a0ah}
+    1: MODULE 0x912b20 <e8822> {a8ah}  top  L2 [P]
+   *1:2: VAR 0x91a780 <e74#> {a22ah} @dt=0xa2e640(w32)  out_wide [O] WIRE
+    1:2:1: BASICDTYPE 0xa2e640 <e2149> {e24ah} @dt=this(sw32)  integer kwd=integer range=[31:0]

 The following summarizes the above example dump, with more detail on each
 field in the section below.
@@ -807,8 +806,9 @@ the `MODULE`, which in turn is the `op1p` pointer under the `NETLIST`
 | `<e74>` | means the 74th edit to the netlist was the last modification to
 this node.

-| `{a22}` | indicates this node is related to line 22 in the source filename
-"a", where "a" is the first file read, "z" the 26th, and "aa" the 27th.
+| `{a22ah}` | indicates this node is related to the source filename "a",
+where "a" is the first file read, "z" the 26th, and "aa" the 27th.  Then
+line 22 in that file, then column 8 (aa=0, az=25, ba=26, ...).

 | `@dt=0x...` | indicates the address of the data type this node contains.

@@ -849,7 +849,10 @@ correspond directly to Verilog entities (for example `MODULE` and
 Address of the node::

 A hexadecimal address of the node in memory. Useful for examining with the
-debugger.
+debugger. If the actual address values are not important, then using the
+`--dump-tree-addrids` option will convert address values to short identifiers
+of the form `([A-Z]*)`, which is hopefully easier for the reader to cross
+reference throughout the dump.

 Last edit number::

@@ -996,6 +999,24 @@ function in `src/verilator.cpp`.
 To get your pass to build you'll need to add its binary filename to the
 list in `src/Makefile_obj.in` and reconfigure.

+=== "Never" features
+
+Verilator ideally would support all of IEEE, and has the goal to get close
+to full support. However the following IEEE sections and features are not
+anticipated to be ever implemented for the reasons indicated.
+
+[horizontal]
+IEEE 1800-2017 3.3 recursive modules:: Little/no tool support, and arguably not a good practice.
+IEEE 1800-2017 6.12 "shortreal":: Little/no tool support, and easily simply promoted to real.
+IEEE 1800-2017 11.11 Min, typ, max:: No SDF support so will always use typical.
+IEEE 1800-2017 11.12 "let":: Little/no tool support, makes difficult to implement parsers.
+IEEE 1800-2017 20.15 Probabilistic functions:: Little industry use.
+IEEE 1800-2017 20.16 Stochastic analysis:: Little industry use.
+IEEE 1800-2017 20.17 PLA modeling:: Little industry use and outdated technology.
+IEEE 1800-2017 31 Timing checks:: No longer relevant with static timing analysis tools.
+IEEE 1800-2017 32 SDF annotation:: No longer relevant with static timing analysis tools.
+IEEE 1800-2017 33 Config:: Little/no tool support or industry use.
+
 == Distribution

 Copyright 2008-2020 by Wilson Snyder.  Verilator is free software; you can
@@ -5,11 +5,9 @@
 # This is an example cmake script to build a verilog to systemc project
 # using cmake and verilator.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################

@@ -6,11 +6,9 @@
 # This makefile is here for testing the examples and should
 # generally not be added to a CMake project.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################

@@ -5,11 +5,9 @@
 # This is an example cmake script to build a verilog to SystemC project
 # using CMake and Verilator.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################

@@ -6,11 +6,9 @@
 # This makefile is here for testing the examples and should
 # generally not be added to a CMake project.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################

@@ -5,11 +5,9 @@
 # This is an example cmake script to build a verilog to systemc project
 # using cmake and verilator.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################

@@ -6,11 +6,9 @@
 # This makefile is here for testing the examples and should
 # generally not be added to a CMake project.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################

@@ -5,11 +5,9 @@
 # This is an example cmake script to build a verilog to systemc project
 # using cmake and verilator.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################

@@ -6,11 +6,9 @@
 # This makefile is here for testing the examples and should
 # generally not be added to a CMake project.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################

@@ -5,11 +5,9 @@
 # This is an example cmake script to build a verilog to SystemC project
 # using CMake and Verilator.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################

@@ -6,11 +6,9 @@
 # This makefile is here for testing the examples and should
 # generally not be added to a CMake project.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################

@@ -5,11 +5,9 @@
 # This calls the object directory makefile.  That allows the objects to
 # be placed in the "current directory" which simplifies the Makefile.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################
 # Check for sanity to avoid later confusion
@@ -19,7 +19,7 @@ int main(int argc, char** argv, char** env) {
    // e.g. examples/c_tracing.

    // Prevent unused variable warnings
-    if (0 && argc && argv && env) {}
+    if (false && argc && argv && env) {}

    // Construct the Verilated model, from Vtop.h generated from Verilating "top.v"
    Vtop* top = new Vtop;
@@ -5,11 +5,9 @@
 # This calls the object directory makefile.  That allows the objects to
 # be placed in the "current directory" which simplifies the Makefile.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################
 # Check for sanity to avoid later confusion
@@ -23,25 +23,17 @@ int sc_main(int argc, char* argv[]) {
    // e.g. examples/c_tracing.

    // Prevent unused variable warnings
-    if (0 && argc && argv) {}
+    if (false && argc && argv) {}

    // Construct the Verilated model, from Vtop.h generated from Verilating "top.v"
    Vtop* top = new Vtop("top");

    // Initialize SC model
-#if (SYSTEMC_VERSION >= 20070314)
    sc_start(1, SC_NS);
-#else
-    sc_start(1);
-#endif

    // Simulate until $finish
    while (!Verilated::gotFinish()) {
-#if (SYSTEMC_VERSION >= 20070314)
        sc_start(1, SC_NS);
-#else
-        sc_start(1);
-#endif
    }

    // Final model cleanup
@@ -5,11 +5,9 @@
 # This calls the object directory makefiles.  That allows the objects to
 # be placed in the "current directory" which simplifies the Makefile.
 #
-# Copyright 2019 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################
 # Check for sanity to avoid later confusion
@@ -70,7 +68,7 @@ run:
 	@echo " library (libverilated_secret.a) generated from the previous"
 	@echo " step"
 	@echo "---------------------------------------------------------------"
-	$(VERILATOR) $(TOP_VERILATOR_FLAGS) --exe -LDFLAGS '-L../obj_dir_secret -lverilated_secret -static' top.v obj_dir_secret/verilated_secret.sv sim_main.cpp
+	$(VERILATOR) $(TOP_VERILATOR_FLAGS) --exe -LDFLAGS '../obj_dir_secret/libverilated_secret.a' top.v obj_dir_secret/verilated_secret.sv sim_main.cpp

 	@echo
 	@echo "-- COMPILE entire design --------------------------------------"
@@ -20,7 +20,7 @@ vluint64_t main_time = 0;
 double sc_time_stamp() { return main_time; }

 int main(int argc, char** argv, char** env) {
-    if (0 && argc && argv && env) {}
+    if (false && argc && argv && env) {}

    Verilated::debug(0);
    Verilated::randReset(2);
@@ -31,7 +31,7 @@ int main(int argc, char** argv, char** env) {

 #if VM_TRACE
    // When tracing, the contents of the secret module will not be seen
-    VerilatedVcdC* tfp = NULL;
+    VerilatedVcdC* tfp = nullptr;
    const char* flag = Verilated::commandArgsPlusMatch("trace");
    if (flag && 0 == strcmp(flag, "+trace")) {
        Verilated::traceEverOn(true);
@@ -62,13 +62,13 @@ int main(int argc, char** argv, char** env) {
 #if VM_TRACE
    if (tfp) {
        tfp->close();
-        tfp = NULL;
+        tfp = nullptr;
    }
 #endif

    // Destroy model
    delete top;
-    top = NULL;
+    top = nullptr;

    // Fin
    exit(0);
@@ -5,11 +5,9 @@
 # This calls the object directory makefile.  That allows the objects to
 # be placed in the "current directory" which simplifies the Makefile.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################
 # Check for sanity to avoid later confusion
@@ -5,11 +5,9 @@
 #
 # This is executed in the object directory, and called by ../Makefile
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 #######################################################################

@@ -22,7 +22,7 @@ int main(int argc, char** argv, char** env) {
    // This is a more complicated example, please also see the simpler examples/make_hello_c.

    // Prevent unused variable warnings
-    if (0 && argc && argv && env) {}
+    if (false && argc && argv && env) {}

    // Set debug level, 0 is off, 9 is highest presently used
    // May be overridden by commandArgs
@@ -99,7 +99,7 @@ int main(int argc, char** argv, char** env) {

    // Destroy model
    delete top;
-    top = NULL;
+    top = nullptr;

    // Fin
    exit(0);
@@ -5,11 +5,9 @@
 # This calls the object directory makefile.  That allows the objects to
 # be placed in the "current directory" which simplifies the Makefile.
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################
 # Check for sanity to avoid later confusion
@@ -5,11 +5,9 @@
 #
 # This is executed in the object directory, and called by ../Makefile
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 #######################################################################

@@ -39,8 +37,8 @@ endif
 # If you build your own rules from scratch, note you need to include
 # SystemC as follows (Vtop.mk file includes verilated.mk with these
 # already).
-# CPPFLAGS += $(SYSTEMC_CXX_FLAGS) -I$(SYSTEMC_INCLUDE)
-# LDFLAGS  += $(SYSTEMC_CXX_FLAGS) -L$(SYSTEMC_LIBDIR)
+# CPPFLAGS += $(SYSTEMC_CXX_FLAGS) $(addprefix -I, $(SYSTEMC_INCLUDE))
+# LDFLAGS  += $(SYSTEMC_CXX_FLAGS) $(addprefix -L, $(SYSTEMC_LIBDIR))

 # See the benchmarking section of bin/verilator.
 # Support class optimizations.  This includes the tracing and symbol table.
@@ -24,7 +24,7 @@ int sc_main(int argc, char* argv[]) {
    // This is a more complicated example, please also see the simpler examples/make_hello_c.

    // Prevent unused variable warnings
-    if (0 && argc && argv) {}
+    if (false && argc && argv) {}

    // Set debug level, 0 is off, 9 is highest presently used
    // May be overridden by commandArgs
@@ -44,21 +44,9 @@ int sc_main(int argc, char* argv[]) {
    // General logfile
    ios::sync_with_stdio();

-    // Defaults time
-#if (SYSTEMC_VERSION > 20011000)
-#else
-    sc_time dut(1.0, sc_ns);
-    sc_set_default_time_unit(dut);
-#endif
-
    // Define clocks
-#if (SYSTEMC_VERSION >= 20070314)
    sc_clock clk("clk", 10, SC_NS, 0.5, 3, SC_NS, true);
    sc_clock fastclk("fastclk", 2, SC_NS, 0.5, 2, SC_NS, true);
-#else
-    sc_clock clk("clk", 10, 0.5, 3, true);
-    sc_clock fastclk("fastclk", 2, 0.5, 2, true);
-#endif

    // Define interconnect
    sc_signal<bool> reset_l;
@@ -89,16 +77,12 @@ int sc_main(int argc, char* argv[]) {

    // You must do one evaluation before enabling waves, in order to allow
    // SystemC to interconnect everything for testing.
-#if (SYSTEMC_VERSION >= 20070314)
    sc_start(1, SC_NS);
-#else
-    sc_start(1);
-#endif

 #if VM_TRACE
    // If verilator was invoked with --trace argument,
    // and if at run time passed the +trace argument, turn on tracing
-    VerilatedVcdSc* tfp = NULL;
+    VerilatedVcdSc* tfp = nullptr;
    const char* flag = Verilated::commandArgsPlusMatch("trace");
    if (flag && 0 == strcmp(flag, "+trace")) {
        cout << "Enabling waves into logs/vlt_dump.vcd...\n";
@@ -125,11 +109,7 @@ int sc_main(int argc, char* argv[]) {
        }

        // Simulate 1ns
-#if (SYSTEMC_VERSION >= 20070314)
        sc_start(1, SC_NS);
-#else
-        sc_start(1);
-#endif
    }

    // Final model cleanup
@@ -139,7 +119,7 @@ int sc_main(int argc, char* argv[]) {
 #if VM_TRACE
    if (tfp) {
        tfp->close();
-        tfp = NULL;
+        tfp = nullptr;
    }
 #endif

@@ -151,7 +131,7 @@ int sc_main(int argc, char* argv[]) {

    // Destroy model
    delete top;
-    top = NULL;
+    top = nullptr;

    // Fin
    return 0;
@@ -2,11 +2,9 @@
 #
 # DESCRIPTION: Verilator Example: XML tests
 #
-# Copyright 2003-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+# This file ONLY is placed under the Creative Commons Public Domain, for
+# any use, without warranty, 2020 by Wilson Snyder.
+# SPDX-License-Identifier: CC0-1.0
 #
 ######################################################################

@@ -3,7 +3,7 @@
 /* config.h.in.  Generated from configure.ac by autoheader.  */

 /* Define to 1 if you have <alloca.h> and it should be used (not on Ultrix). */
-#if !defined(__MINGW32__)
+#if !defined(__MINGW32__) && !defined(__FreeBSD__)
 # define HAVE_ALLOCA_H 1
 #endif

@@ -794,6 +794,7 @@ pthread_t thread;
 pthread_attr_t thread_attr;
 struct fstWriterContext *xc_parent;
 #endif
+unsigned in_pthread : 1;

 size_t fst_orig_break_size;
 size_t fst_orig_break_add_size;
@@ -1806,10 +1807,9 @@ static void *fstWriterFlushContextPrivate1(void *ctx)
 {
 struct fstWriterContext *xc = (struct fstWriterContext *)ctx;

+pthread_mutex_lock(&(xc->xc_parent->mutex));
 fstWriterFlushContextPrivate2(xc);

-pthread_mutex_unlock(&(xc->xc_parent->mutex));
-
 #ifdef FST_REMOVE_DUPLICATE_VC
 free(xc->curval_mem);
 #endif
@@ -1818,6 +1818,9 @@ free(xc->vchg_mem);
 tmpfile_close(&xc->tchn_handle, &xc->tchn_handle_nam);
 free(xc);

+xc->xc_parent->in_pthread = 0;
+pthread_mutex_unlock(&(xc->xc_parent->mutex));
+
 return(NULL);
 }

@@ -1865,7 +1868,15 @@ if(xc->parallel_enabled)
        xc->section_header_only = 0;
        xc->secnum++;

+	while (xc->in_pthread) 
+		{ 
+		pthread_mutex_lock(&xc->mutex); 
+		pthread_mutex_unlock(&xc->mutex); 
+		};
+
        pthread_mutex_lock(&xc->mutex);
+	xc->in_pthread = 1;
+        pthread_mutex_unlock(&xc->mutex);

        pthread_create(&xc->thread, &xc->thread_attr, fstWriterFlushContextPrivate1, xc2);
        }
@@ -1947,6 +1958,12 @@ if(xc && !xc->already_in_close && !xc->already_in_flush)
 #ifdef FST_WRITER_PARALLEL
                        pthread_mutex_lock(&xc->mutex);
                        pthread_mutex_unlock(&xc->mutex);
+
+			while (xc->in_pthread) 
+				{ 
+				pthread_mutex_lock(&xc->mutex); 
+				pthread_mutex_unlock(&xc->mutex); 
+				};
 #endif
                        }
                }
@@ -61,7 +61,7 @@

 // Version check
 #if defined(SYSTEMC_VERSION) && (SYSTEMC_VERSION < 20111121)
-# warning "Verilator soon requires SystemC 2.3.*; see manual for deprecated other versions."
+# warning "Verilator requires SystemC 2.3.* or newer."
 #endif
 // clang-format on

@@ -84,10 +84,6 @@ typedef EData        WData;     ///< Verilated pack data, >64 bits, as an array
 typedef const WData* WDataInP;  ///< Array input to a function
 typedef WData* WDataOutP;  ///< Array output from a function

-typedef void (*VerilatedVoidCb)(void);
-
-class SpTraceVcd;
-class SpTraceVcdCFile;
 class VerilatedEvalMsgQueue;
 class VerilatedScopeNameMap;
 class VerilatedVar;
@@ -98,7 +94,7 @@ class VerilatedVcdSc;
 class VerilatedFst;
 class VerilatedFstC;

-enum VerilatedVarType {
+enum VerilatedVarType : vluint8_t {
    VLVT_UNKNOWN = 0,
    VLVT_PTR,  // Pointer to something
    VLVT_UINT8,  // AKA CData
@@ -167,7 +163,7 @@ private:

 public:
    explicit VerilatedLockGuard(VerilatedMutex& mutexr) VL_ACQUIRE(mutexr)
-        : m_mutexr(mutexr) {
+        : m_mutexr(mutexr) {  // Need () or GCC 4.8 false warning
        m_mutexr.lock();
    }
    ~VerilatedLockGuard() VL_RELEASE() { m_mutexr.unlock(); }
@@ -207,7 +203,7 @@ public:
    /// The constructor establishes the thread id for all later calls.
    /// If necessary, a different class could be made that inits it otherwise.
    VerilatedAssertOneThread()
-        : m_threadid(VL_THREAD_ID()) {}
+        : m_threadid{VL_THREAD_ID()} {}
    ~VerilatedAssertOneThread() { check(); }
    // METHODS
    /// Check that the current thread ID is the same as the construction thread ID
@@ -317,30 +313,30 @@ public:  // But for internal use only

 class VerilatedScope {
 public:
-    typedef enum {
+    typedef enum : vluint8_t {
        SCOPE_MODULE,
        SCOPE_OTHER
    } Type;  // Type of a scope, currently module is only interesting
 private:
    // Fastpath:
-    VerilatedSyms* m_symsp;  ///< Symbol table
-    void** m_callbacksp;  ///< Callback table pointer (Fastpath)
-    int m_funcnumMax;  ///< Maxium function number stored (Fastpath)
+    VerilatedSyms* m_symsp = nullptr;  ///< Symbol table
+    void** m_callbacksp = nullptr;  ///< Callback table pointer (Fastpath)
+    int m_funcnumMax = 0;  ///< Maxium function number stored (Fastpath)
    // 4 bytes padding (on -m64), for rent.
-    VerilatedVarNameMap* m_varsp;  ///< Variable map
-    const char* m_namep;  ///< Scope name (Slowpath)
-    const char* m_identifierp;  ///< Identifier of scope (with escapes removed)
-    vlsint8_t m_timeunit;  ///< Timeunit in negative power-of-10
-    Type m_type;  ///< Type of the scope
+    VerilatedVarNameMap* m_varsp = nullptr;  ///< Variable map
+    const char* m_namep = nullptr;  ///< Scope name (Slowpath)
+    const char* m_identifierp = nullptr;  ///< Identifier of scope (with escapes removed)
+    vlsint8_t m_timeunit = 0;  ///< Timeunit in negative power-of-10
+    Type m_type = SCOPE_OTHER;  ///< Type of the scope

 public:  // But internals only - called from VerilatedModule's
    VerilatedScope();
    ~VerilatedScope();
    void configure(VerilatedSyms* symsp, const char* prefixp, const char* suffixp,
-                   const char* identifier, vlsint8_t timeunit, const Type type) VL_MT_UNSAFE;
+                   const char* identifier, vlsint8_t timeunit, const Type& type) VL_MT_UNSAFE;
    void exportInsert(int finalize, const char* namep, void* cb) VL_MT_UNSAFE;
-    void varInsert(int finalize, const char* namep, void* datap, VerilatedVarType vltype,
-                   int vlflags, int dims, ...) VL_MT_UNSAFE;
+    void varInsert(int finalize, const char* namep, void* datap, bool isParam,
+                   VerilatedVarType vltype, int vlflags, int dims, ...) VL_MT_UNSAFE;
    // ACCESSORS
    const char* name() const { return m_namep; }
    const char* identifier() const { return m_identifierp; }
@@ -365,7 +361,7 @@ public:  // But internals only - called from VerilatedModule's

 class VerilatedHierarchy {
 public:
-    void add(VerilatedScope* fromp, VerilatedScope* top);
+    static void add(VerilatedScope* fromp, VerilatedScope* top);
 };

 //===========================================================================
@@ -376,8 +372,6 @@ class Verilated {
    // Slow path variables
    static VerilatedMutex m_mutex;  ///< Mutex for s_s/s_ns members, when VL_THREADED

-    static VerilatedVoidCb s_flushCb;  ///< Flush callback function
-
    static struct Serialized {  // All these members serialized/deserialized
        // Fast path
        int s_debug;  ///< See accessors... only when VL_DEBUG set
@@ -386,8 +380,8 @@ class Verilated {
        bool s_assertOn;  ///< Assertions are enabled
        bool s_fatalOnVpiError;  ///< Stop on vpi error/unsupported
        // Slow path
-        unsigned s_timeunit : 4;  ///< Time unit as 0..15
-        unsigned s_timeprecision : 4;  ///< Time precision as 0..15
+        vlsint8_t s_timeunit;  ///< Time unit as 0..15
+        vlsint8_t s_timeprecision;  ///< Time precision as 0..15
        int s_errorCount;  ///< Number of errors
        int s_errorLimit;  ///< Stop on error number
        int s_randReset;  ///< Random reset: 0=all 0s, 1=all 1s, 2=random
@@ -399,8 +393,8 @@ class Verilated {
    static struct NonSerialized {  // Non-serialized information
        // These are reloaded from on command-line settings, so do not need to persist
        // Fast path
-        vluint64_t s_profThreadsStart;  ///< +prof+threads starting time
-        vluint32_t s_profThreadsWindow;  ///< +prof+threads window size
+        vluint64_t s_profThreadsStart = 1;  ///< +prof+threads starting time
+        vluint32_t s_profThreadsWindow = 2;  ///< +prof+threads window size
        // Slow path
        const char* s_profThreadsFilenamep;  ///< +prof+threads filename
        NonSerialized();
@@ -411,23 +405,22 @@ class Verilated {
    // assumption is that the restore is allowed to pass different arguments
    static struct CommandArgValues {
        VerilatedMutex m_argMutex;  ///< Mutex for s_args members, when VL_THREADED
-        int argc;
-        const char** argv;
-        CommandArgValues()
-            : argc(0)
-            , argv(NULL) {}
+        int argc = 0;
+        const char** argv = nullptr;
+        CommandArgValues() {}
        ~CommandArgValues() {}
    } s_args;

    // Not covered by mutex, as per-thread
    static VL_THREAD_LOCAL struct ThreadLocal {
 #ifdef VL_THREADED
-        vluint32_t t_mtaskId;  ///< Current mtask# executing on this thread
-        vluint32_t t_endOfEvalReqd;  ///< Messages may be pending, thread needs endOf-eval calls
+        vluint32_t t_mtaskId = 0;  ///< Current mtask# executing on this thread
+        vluint32_t t_endOfEvalReqd
+            = 0;  ///< Messages may be pending, thread needs endOf-eval calls
 #endif
-        const VerilatedScope* t_dpiScopep;  ///< DPI context scope
-        const char* t_dpiFilename;  ///< DPI context filename
-        int t_dpiLineno;  ///< DPI context line number
+        const VerilatedScope* t_dpiScopep = nullptr;  ///< DPI context scope
+        const char* t_dpiFilename = nullptr;  ///< DPI context filename
+        int t_dpiLineno = 0;  ///< DPI context line number

        ThreadLocal();
        ~ThreadLocal();
@@ -501,9 +494,15 @@ public:
    static void profThreadsFilenamep(const char* flagp) VL_MT_SAFE;
    static const char* profThreadsFilenamep() VL_MT_SAFE { return s_ns.s_profThreadsFilenamep; }

-    /// Flush callback for VCD waves
-    static void flushCb(VerilatedVoidCb cb) VL_MT_SAFE;
-    static void flushCall() VL_MT_SAFE;
+    typedef void (*VoidPCb)(void*);  // Callback type for below
+    /// Callbacks to run on global flush
+    static void addFlushCb(VoidPCb cb, void* datap) VL_MT_SAFE;
+    static void removeFlushCb(VoidPCb cb, void* datap) VL_MT_SAFE;
+    static void runFlushCallbacks() VL_MT_SAFE;
+    /// Callbacks to run prior to termination
+    static void addExitCb(VoidPCb cb, void* datap) VL_MT_SAFE;
+    static void removeExitCb(VoidPCb cb, void* datap) VL_MT_SAFE;
+    static void runExitCallbacks() VL_MT_SAFE;

    /// Record command line arguments, for retrieval by $test$plusargs/$value$plusargs,
    /// and for parsing +verilator+ run-time arguments.
@@ -561,8 +560,8 @@ public:
        t_s.t_dpiFilename = filenamep;
        t_s.t_dpiLineno = lineno;
    }
-    static void dpiClearContext() VL_MT_SAFE { t_s.t_dpiScopep = NULL; }
-    static bool dpiInContext() VL_MT_SAFE { return t_s.t_dpiScopep != NULL; }
+    static void dpiClearContext() VL_MT_SAFE { t_s.t_dpiScopep = nullptr; }
+    static bool dpiInContext() VL_MT_SAFE { return t_s.t_dpiScopep != nullptr; }
    static const char* dpiFilenamep() VL_MT_SAFE { return t_s.t_dpiFilename; }
    static int dpiLineno() VL_MT_SAFE { return t_s.t_dpiLineno; }
    static int exportFuncNum(const char* namep) VL_MT_SAFE;
@@ -644,9 +643,19 @@ extern void VL_PRINTF_MT(const char* formatp, ...) VL_ATTR_PRINTF(1) VL_MT_SAFE;
 /// Print a debug message from internals with standard prefix, with printf style format
 extern void VL_DBG_MSGF(const char* formatp, ...) VL_ATTR_PRINTF(1) VL_MT_SAFE;

-extern IData VL_RANDOM_I(int obits);  ///< Randomize a signal
-extern QData VL_RANDOM_Q(int obits);  ///< Randomize a signal
+extern vluint64_t vl_rand64() VL_MT_SAFE;
+inline IData VL_RANDOM_I(int obits) VL_MT_SAFE { return vl_rand64() & VL_MASK_I(obits); }
+inline QData VL_RANDOM_Q(int obits) VL_MT_SAFE { return vl_rand64() & VL_MASK_Q(obits); }
 extern WDataOutP VL_RANDOM_W(int obits, WDataOutP outwp);  ///< Randomize a signal
+inline IData VL_URANDOM_RANGE_I(IData hi, IData lo) {
+    vluint64_t rnd = vl_rand64();
+    if (VL_LIKELY(hi > lo)) {
+        // Modulus isn't very fast but it's common that hi-low is power-of-two
+        return (rnd % (hi - lo)) + lo;
+    } else {
+        return (rnd % (lo - hi)) + hi;
+    }
+}

 /// Init time only, so slow is fine
 extern IData VL_RAND_RESET_I(int obits);  ///< Random reset a signal
@@ -673,13 +682,9 @@ extern WDataOutP _vl_moddiv_w(int lbits, WDataOutP owp, WDataInP lwp, WDataInP r
 /// File I/O
 extern IData VL_FGETS_IXI(int obits, void* destp, IData fpi);

-extern IData VL_FOPEN_S(const char* filenamep, const char* modep);
-extern IData VL_FOPEN_WI(int fnwords, WDataInP filenamep, IData mode);
-extern IData VL_FOPEN_QI(QData filename, IData mode);
-inline IData VL_FOPEN_II(IData filename, IData mode) VL_MT_SAFE {
-    return VL_FOPEN_QI(filename, mode);
-}
-
+extern void VL_FFLUSH_I(IData fdi);
+extern IData VL_FSEEK_I(IData fdi, IData offset, IData origin);
+extern IData VL_FTELL_I(IData fdi);
 extern void VL_FCLOSE_I(IData fdi);

 extern IData VL_FREAD_I(int width, int array_lsb, int array_size, void* memp, IData fpi,
@@ -711,7 +716,7 @@ extern const char* vl_mc_scan_plusargs(const char* prefixp);  // PLIish

 /// Return true if data[bit] set; not 0/1 return, but 0/non-zero return.
 #define VL_BITISSET_I(data, bit) ((data) & (VL_UL(1) << VL_BITBIT_I(bit)))
-#define VL_BITISSET_Q(data, bit) ((data) & (VL_ULL(1) << VL_BITBIT_Q(bit)))
+#define VL_BITISSET_Q(data, bit) ((data) & (1ULL << VL_BITBIT_Q(bit)))
 #define VL_BITISSET_E(data, bit) ((data) & (VL_EUL(1) << VL_BITBIT_E(bit)))
 #define VL_BITISSET_W(data, bit) ((data)[VL_BITWORD_E(bit)] & (VL_EUL(1) << VL_BITBIT_E(bit)))
 #define VL_BITISSETLIMIT_W(data, width, bit) (((bit) < (width)) && VL_BITISSET_W(data, bit))
@@ -722,22 +727,22 @@ extern const char* vl_mc_scan_plusargs(const char* prefixp);  // PLIish
 /// Create two 32-bit words from quadword
 /// WData is always at least 2 words; does not clean upper bits
 #define VL_SET_WQ(owp, data) \
-    { \
+    do { \
        (owp)[0] = static_cast<IData>(data); \
        (owp)[1] = static_cast<IData>((data) >> VL_EDATASIZE); \
-    }
+    } while (false)
 #define VL_SET_WI(owp, data) \
-    { \
+    do { \
        (owp)[0] = static_cast<IData>(data); \
        (owp)[1] = 0; \
-    }
+    } while (false)
 #define VL_SET_QW(lwp) \
    ((static_cast<QData>((lwp)[0])) \
     | (static_cast<QData>((lwp)[1]) << (static_cast<QData>(VL_EDATASIZE))))
-#define _VL_SET_QII(ld, rd) ((static_cast<QData>(ld) << VL_ULL(32)) | static_cast<QData>(rd))
+#define _VL_SET_QII(ld, rd) ((static_cast<QData>(ld) << 32ULL) | static_cast<QData>(rd))

 /// Return FILE* from IData
-extern FILE* VL_CVT_I_FP(IData lhs);
+extern FILE* VL_CVT_I_FP(IData lhs) VL_MT_SAFE;

 // clang-format off
 // Use a union to avoid cast-to-different-size warnings
@@ -768,9 +773,27 @@ static inline QData VL_CVT_Q_D(double lhs) VL_PURE {
 }
 // clang-format on

-/// Return double from QData (numeric)
-static inline double VL_ITOR_D_I(IData lhs) VL_PURE {
-    return static_cast<double>(static_cast<vlsint32_t>(lhs));
+/// Return double from lhs (numeric) unsigned
+double VL_ITOR_D_W(int lbits, WDataInP lwp) VL_PURE;
+static inline double VL_ITOR_D_I(int, IData lhs) VL_PURE {
+    return static_cast<double>(static_cast<vluint32_t>(lhs));
+}
+static inline double VL_ITOR_D_Q(int, QData lhs) VL_PURE {
+    return static_cast<double>(static_cast<vluint64_t>(lhs));
+}
+/// Return double from lhs (numeric) signed
+double VL_ISTOR_D_W(int lbits, WDataInP lwp) VL_PURE;
+static inline double VL_ISTOR_D_I(int lbits, IData lhs) VL_PURE {
+    if (lbits == 32) return static_cast<double>(static_cast<vlsint32_t>(lhs));
+    WData lwp[VL_WQ_WORDS_E];
+    VL_SET_WI(lwp, lhs);
+    return VL_ISTOR_D_W(lbits, lwp);
+}
+static inline double VL_ISTOR_D_Q(int lbits, QData lhs) VL_PURE {
+    if (lbits == 64) return static_cast<double>(static_cast<vlsint64_t>(lhs));
+    WData lwp[VL_WQ_WORDS_E];
+    VL_SET_WQ(lwp, lhs);
+    return VL_ISTOR_D_W(lbits, lwp);
 }
 /// Return QData from double (numeric)
 static inline IData VL_RTOI_I_D(double lhs) VL_PURE {
@@ -780,7 +803,7 @@ static inline IData VL_RTOI_I_D(double lhs) VL_PURE {
 // Sign extend such that if MSB set, we get ffff_ffff, else 0s
 // (Requires clean input)
 #define VL_SIGN_I(nbits, lhs) ((lhs) >> VL_BITBIT_I((nbits)-VL_UL(1)))
-#define VL_SIGN_Q(nbits, lhs) ((lhs) >> VL_BITBIT_Q((nbits)-VL_ULL(1)))
+#define VL_SIGN_Q(nbits, lhs) ((lhs) >> VL_BITBIT_Q((nbits)-1ULL))
 #define VL_SIGN_E(nbits, lhs) ((lhs) >> VL_BITBIT_E((nbits)-VL_EUL(1)))
 #define VL_SIGN_W(nbits, rwp) \
    ((rwp)[VL_BITWORD_E((nbits)-VL_EUL(1))] >> VL_BITBIT_E((nbits)-VL_EUL(1)))
@@ -792,7 +815,7 @@ static inline IData VL_EXTENDSIGN_I(int lbits, IData lhs) VL_PURE {
    return (-((lhs) & (VL_UL(1) << (lbits - 1))));
 }
 static inline QData VL_EXTENDSIGN_Q(int lbits, QData lhs) VL_PURE {
-    return (-((lhs) & (VL_ULL(1) << (lbits - 1))));
+    return (-((lhs) & (1ULL << (lbits - 1))));
 }

 // Debugging prints
@@ -823,13 +846,8 @@ extern int VL_TIME_STR_CONVERT(const char* strp) VL_PURE;

 /// Return current simulation time
 #if defined(SYSTEMC_VERSION)
-# if SYSTEMC_VERSION > 20011000
 // Already defined: extern sc_time sc_time_stamp();
 inline vluint64_t vl_time_stamp64() { return sc_time_stamp().value(); }
-# else  // Before SystemC changed to integral time representation
-// Already defined: extern double sc_time_stamp();
-inline vluint64_t vl_time_stamp64() { return static_cast<vluint64_t>(sc_time_stamp()); }
-# endif
 #else  // Non-SystemC
 # ifdef VL_TIME_STAMP64
 extern vluint64_t vl_time_stamp64();
@@ -847,7 +865,7 @@ inline vluint64_t vl_time_stamp64() { return static_cast<vluint64_t>(sc_time_sta
 // Optimized assuming scale is always constant.
 // Can't use multiply in Q flavor, as might lose precision
 #define VL_TIME_UNITED_Q(scale) (VL_TIME_Q() / static_cast<QData>(scale))
-#define VL_TIME_UNITED_D(scale) (VL_TIME_D() * (1.0 / (scale)))
+#define VL_TIME_UNITED_D(scale) (VL_TIME_D() / static_cast<double>(scale))
 /// Time imported from units to time precision
 double vl_time_multiplier(int scale);

@@ -930,8 +948,7 @@ static inline void VL_ASSIGNBIT_II(int, int bit, IData& lhsr, IData rhs) VL_PURE
    lhsr = ((lhsr & ~(VL_UL(1) << VL_BITBIT_I(bit))) | (rhs << VL_BITBIT_I(bit)));
 }
 static inline void VL_ASSIGNBIT_QI(int, int bit, QData& lhsr, QData rhs) VL_PURE {
-    lhsr = ((lhsr & ~(VL_ULL(1) << VL_BITBIT_Q(bit)))
-            | (static_cast<QData>(rhs) << VL_BITBIT_Q(bit)));
+    lhsr = ((lhsr & ~(1ULL << VL_BITBIT_Q(bit))) | (static_cast<QData>(rhs) << VL_BITBIT_Q(bit)));
 }
 static inline void VL_ASSIGNBIT_WI(int, int bit, WDataOutP owp, IData rhs) VL_MT_SAFE {
    EData orig = owp[VL_BITWORD_E(bit)];
@@ -949,7 +966,7 @@ static inline void VL_ASSIGNBIT_IO(int, int bit, IData& lhsr, IData) VL_PURE {
    lhsr = (lhsr | (VL_UL(1) << VL_BITBIT_I(bit)));
 }
 static inline void VL_ASSIGNBIT_QO(int, int bit, QData& lhsr, IData) VL_PURE {
-    lhsr = (lhsr | (VL_ULL(1) << VL_BITBIT_Q(bit)));
+    lhsr = (lhsr | (1ULL << VL_BITBIT_Q(bit)));
 }
 static inline void VL_ASSIGNBIT_WO(int, int bit, WDataOutP owp, IData) VL_MT_SAFE {
    EData orig = owp[VL_BITWORD_E(bit)];
@@ -1217,6 +1234,36 @@ static inline IData VL_COUNTONES_W(int words, WDataInP lwp) VL_MT_SAFE {
    return r;
 }

+// EMIT_RULE: VL_COUNTBITS_II:  oclean = false; lhs clean
+static inline IData VL_COUNTBITS_I(int lbits, IData lhs, IData ctrl0, IData ctrl1,
+                                   IData ctrl2) VL_PURE {
+    int ctrlSum = (ctrl0 & 0x1) + (ctrl1 & 0x1) + (ctrl2 & 0x1);
+    if (ctrlSum == 3) {
+        return VL_COUNTONES_I(lhs);
+    } else if (ctrlSum == 0) {
+        IData mask = (lbits == 32) ? -1 : ((1 << lbits) - 1);
+        return VL_COUNTONES_I(~lhs & mask);
+    } else {
+        return (lbits == 32) ? 32 : lbits;
+    }
+}
+static inline IData VL_COUNTBITS_Q(int lbits, QData lhs, IData ctrl0, IData ctrl1,
+                                   IData ctrl2) VL_PURE {
+    return VL_COUNTBITS_I(32, static_cast<IData>(lhs), ctrl0, ctrl1, ctrl2)
+           + VL_COUNTBITS_I(lbits - 32, static_cast<IData>(lhs >> 32), ctrl0, ctrl1, ctrl2);
+}
+#define VL_COUNTBITS_E VL_COUNTBITS_I
+static inline IData VL_COUNTBITS_W(int lbits, int words, WDataInP lwp, IData ctrl0, IData ctrl1,
+                                   IData ctrl2) VL_MT_SAFE {
+    EData r = 0;
+    IData wordLbits = 32;
+    for (int i = 0; i < words; ++i) {
+        if (i == words - 1) { wordLbits = lbits % 32; }
+        r += VL_COUNTBITS_E(wordLbits, lwp[i], ctrl0, ctrl1, ctrl2);
+    }
+    return r;
+}
+
 static inline IData VL_ONEHOT_I(IData lhs) VL_PURE {
    return (((lhs & (lhs - 1)) == 0) & (lhs != 0));
 }
@@ -1261,7 +1308,7 @@ static inline IData VL_CLOG2_Q(QData lhs) VL_PURE {
    if (VL_UNLIKELY(!lhs)) return 0;
    lhs--;
    int shifts = 0;
-    for (; lhs != 0; ++shifts) lhs = lhs >> VL_ULL(1);
+    for (; lhs != 0; ++shifts) lhs = lhs >> 1ULL;
    return shifts;
 }
 static inline IData VL_CLOG2_W(int words, WDataInP lwp) VL_MT_SAFE {
@@ -1428,6 +1475,7 @@ static inline int _VL_CMPS_W(int lbits, WDataInP lwp, WDataInP rwp) VL_MT_SAFE {
 //=========================================================================
 // Math

+// Output NOT clean
 static inline WDataOutP VL_NEGATE_W(int words, WDataOutP owp, WDataInP lwp) VL_MT_SAFE {
    EData carry = 1;
    for (int i = 0; i < words; ++i) {
@@ -1459,8 +1507,8 @@ static inline WDataOutP VL_ADD_W(int words, WDataOutP owp, WDataInP lwp, WDataIn
    QData carry = 0;
    for (int i = 0; i < words; ++i) {
        carry = carry + static_cast<QData>(lwp[i]) + static_cast<QData>(rwp[i]);
-        owp[i] = (carry & VL_ULL(0xffffffff));
-        carry = (carry >> VL_ULL(32)) & VL_ULL(0xffffffff);
+        owp[i] = (carry & 0xffffffffULL);
+        carry = (carry >> 32ULL) & 0xffffffffULL;
    }
    // Last output word is dirty
    return owp;
@@ -1472,8 +1520,8 @@ static inline WDataOutP VL_SUB_W(int words, WDataOutP owp, WDataInP lwp, WDataIn
        carry = (carry + static_cast<QData>(lwp[i])
                 + static_cast<QData>(static_cast<IData>(~rwp[i])));
        if (i == 0) ++carry;  // Negation of rwp
-        owp[i] = (carry & VL_ULL(0xffffffff));
-        carry = (carry >> VL_ULL(32)) & VL_ULL(0xffffffff);
+        owp[i] = (carry & 0xffffffffULL);
+        carry = (carry >> 32ULL) & 0xffffffffULL;
    }
    // Last output word is dirty
    return owp;
@@ -1486,8 +1534,8 @@ static inline WDataOutP VL_MUL_W(int words, WDataOutP owp, WDataInP lwp, WDataIn
            QData mul = static_cast<QData>(lwp[lword]) * static_cast<QData>(rwp[rword]);
            for (int qword = lword + rword; qword < words; ++qword) {
                mul += static_cast<QData>(owp[qword]);
-                owp[qword] = (mul & VL_ULL(0xffffffff));
-                mul = (mul >> VL_ULL(32)) & VL_ULL(0xffffffff);
+                owp[qword] = (mul & 0xffffffffULL);
+                mul = (mul >> 32ULL) & 0xffffffffULL;
            }
        }
    }
@@ -1535,8 +1583,8 @@ static inline WDataOutP VL_MULS_WWW(int, int lbits, int, WDataOutP owp, WDataInP
        for (int i = 0; i < words; ++i) {
            carry = carry + static_cast<QData>(static_cast<IData>(~owp[i]));
            if (i == 0) ++carry;  // Negation of temp2
-            owp[i] = (carry & VL_ULL(0xffffffff));
-            carry = (carry >> VL_ULL(32)) & VL_ULL(0xffffffff);
+            owp[i] = (carry & 0xffffffffULL);
+            carry = (carry >> 32ULL) & 0xffffffffULL;
        }
        // Not needed: owp[words-1] |= 1<<VL_BITBIT_E(lbits-1);  // Set sign bit
    }
@@ -1546,24 +1594,30 @@ static inline WDataOutP VL_MULS_WWW(int, int lbits, int, WDataOutP owp, WDataInP

 static inline IData VL_DIVS_III(int lbits, IData lhs, IData rhs) VL_PURE {
    if (VL_UNLIKELY(rhs == 0)) return 0;
+    // -MAX / -1 cannot be represented in twos complement, and will cause SIGFPE
+    if (VL_UNLIKELY(lhs == 0x80000000 && rhs == 0xffffffff)) return 0;
    vlsint32_t lhs_signed = VL_EXTENDS_II(VL_IDATASIZE, lbits, lhs);
    vlsint32_t rhs_signed = VL_EXTENDS_II(VL_IDATASIZE, lbits, rhs);
    return lhs_signed / rhs_signed;
 }
 static inline QData VL_DIVS_QQQ(int lbits, QData lhs, QData rhs) VL_PURE {
    if (VL_UNLIKELY(rhs == 0)) return 0;
+    // -MAX / -1 cannot be represented in twos complement, and will cause SIGFPE
+    if (VL_UNLIKELY(lhs == 0x8000000000000000ULL && rhs == 0xffffffffffffffffULL)) return 0;
    vlsint64_t lhs_signed = VL_EXTENDS_QQ(VL_QUADSIZE, lbits, lhs);
    vlsint64_t rhs_signed = VL_EXTENDS_QQ(VL_QUADSIZE, lbits, rhs);
    return lhs_signed / rhs_signed;
 }
 static inline IData VL_MODDIVS_III(int lbits, IData lhs, IData rhs) VL_PURE {
    if (VL_UNLIKELY(rhs == 0)) return 0;
+    if (VL_UNLIKELY(lhs == 0x80000000 && rhs == 0xffffffff)) return 0;
    vlsint32_t lhs_signed = VL_EXTENDS_II(VL_IDATASIZE, lbits, lhs);
    vlsint32_t rhs_signed = VL_EXTENDS_II(VL_IDATASIZE, lbits, rhs);
    return lhs_signed % rhs_signed;
 }
 static inline QData VL_MODDIVS_QQQ(int lbits, QData lhs, QData rhs) VL_PURE {
    if (VL_UNLIKELY(rhs == 0)) return 0;
+    if (VL_UNLIKELY(lhs == 0x8000000000000000ULL && rhs == 0xffffffffffffffffULL)) return 0;
    vlsint64_t lhs_signed = VL_EXTENDS_QQ(VL_QUADSIZE, lbits, lhs);
    vlsint64_t rhs_signed = VL_EXTENDS_QQ(VL_QUADSIZE, lbits, rhs);
    return lhs_signed % rhs_signed;
@@ -1627,7 +1681,7 @@ static inline IData VL_POW_III(int, int, int rbits, IData lhs, IData rhs) VL_PUR
    IData out = 1;
    for (int i = 0; i < rbits; ++i) {
        if (i > 0) power = power * power;
-        if (rhs & (VL_ULL(1) << i)) out *= power;
+        if (rhs & (1ULL << i)) out *= power;
    }
    return out;
 }
@@ -1635,10 +1689,10 @@ static inline QData VL_POW_QQQ(int, int, int rbits, QData lhs, QData rhs) VL_PUR
    if (VL_UNLIKELY(rhs == 0)) return 1;
    if (VL_UNLIKELY(lhs == 0)) return 0;
    QData power = lhs;
-    QData out = VL_ULL(1);
+    QData out = 1ULL;
    for (int i = 0; i < rbits; ++i) {
        if (i > 0) power = power * power;
-        if (rhs & (VL_ULL(1) << i)) out *= power;
+        if (rhs & (1ULL << i)) out *= power;
    }
    return out;
 }
@@ -1884,7 +1938,8 @@ static inline IData VL_STREAML_FAST_III(int, int lbits, int, IData ld, IData rd_
    case 1: ret = ((ret >> 2) & VL_UL(0x33333333)) | ((ret & VL_UL(0x33333333)) << 2);  // FALLTHRU
    case 2: ret = ((ret >> 4) & VL_UL(0x0f0f0f0f)) | ((ret & VL_UL(0x0f0f0f0f)) << 4);  // FALLTHRU
    case 3: ret = ((ret >> 8) & VL_UL(0x00ff00ff)) | ((ret & VL_UL(0x00ff00ff)) << 8);  // FALLTHRU
-    case 4: ret = ((ret >> 16) | (ret << 16));
+    case 4: ret = ((ret >> 16) | (ret << 16));  // FALLTHRU
+    default:;
    }
    return ret >> (VL_IDATASIZE - lbits);
 }
@@ -1896,25 +1951,26 @@ static inline QData VL_STREAML_FAST_QQI(int, int lbits, int, QData ld, IData rd_
        vluint32_t lbitsFloor = lbits & ~VL_MASK_I(rd_log2);
        vluint32_t lbitsRem = lbits - lbitsFloor;
        QData msbMask = VL_MASK_Q(lbitsRem) << lbitsFloor;
-        ret = (ret & ~msbMask) | ((ret & msbMask) << ((VL_ULL(1) << rd_log2) - lbitsRem));
+        ret = (ret & ~msbMask) | ((ret & msbMask) << ((1ULL << rd_log2) - lbitsRem));
    }
    switch (rd_log2) {
    case 0:
-        ret = (((ret >> 1) & VL_ULL(0x5555555555555555))
-               | ((ret & VL_ULL(0x5555555555555555)) << 1));  // FALLTHRU
+        ret = (((ret >> 1) & 0x5555555555555555ULL)
+               | ((ret & 0x5555555555555555ULL) << 1));  // FALLTHRU
    case 1:
-        ret = (((ret >> 2) & VL_ULL(0x3333333333333333))
-               | ((ret & VL_ULL(0x3333333333333333)) << 2));  // FALLTHRU
+        ret = (((ret >> 2) & 0x3333333333333333ULL)
+               | ((ret & 0x3333333333333333ULL) << 2));  // FALLTHRU
    case 2:
-        ret = (((ret >> 4) & VL_ULL(0x0f0f0f0f0f0f0f0f))
-               | ((ret & VL_ULL(0x0f0f0f0f0f0f0f0f)) << 4));  // FALLTHRU
+        ret = (((ret >> 4) & 0x0f0f0f0f0f0f0f0fULL)
+               | ((ret & 0x0f0f0f0f0f0f0f0fULL) << 4));  // FALLTHRU
    case 3:
-        ret = (((ret >> 8) & VL_ULL(0x00ff00ff00ff00ff))
-               | ((ret & VL_ULL(0x00ff00ff00ff00ff)) << 8));  // FALLTHRU
+        ret = (((ret >> 8) & 0x00ff00ff00ff00ffULL)
+               | ((ret & 0x00ff00ff00ff00ffULL) << 8));  // FALLTHRU
    case 4:
-        ret = (((ret >> 16) & VL_ULL(0x0000ffff0000ffff))
-               | ((ret & VL_ULL(0x0000ffff0000ffff)) << 16));  // FALLTHRU
-    case 5: ret = ((ret >> 32) | (ret << 32));
+        ret = (((ret >> 16) & 0x0000ffff0000ffffULL)
+               | ((ret & 0x0000ffff0000ffffULL) << 16));  // FALLTHRU
+    case 5: ret = ((ret >> 32) | (ret << 32));  // FALLTHRU
+    default:;
    }
    return ret >> (VL_QUADSIZE - lbits);
 }
@@ -2358,14 +2414,14 @@ static inline WDataOutP VL_SEL_WWII(int obits, int lbits, int, int, WDataOutP ow

 /// Return QData from double (numeric)
 // EMIT_RULE: VL_RTOIROUND_Q_D:  oclean=dirty; lclean==clean/real
-static inline QData VL_RTOIROUND_Q_D(int bits, double lhs) VL_PURE {
+static inline QData VL_RTOIROUND_Q_D(int, double lhs) VL_PURE {
    // IEEE format: [63]=sign [62:52]=exp+1023 [51:0]=mantissa
    // This does not need to support subnormals as they are sub-integral
    lhs = VL_ROUND(lhs);
    if (lhs == 0.0) return 0;
    QData q = VL_CVT_Q_D(lhs);
-    int lsb = static_cast<int>((q >> VL_ULL(52)) & VL_MASK_Q(11)) - 1023 - 52;
-    vluint64_t mantissa = (q & VL_MASK_Q(52)) | (VL_ULL(1) << 52);
+    int lsb = static_cast<int>((q >> 52ULL) & VL_MASK_Q(11)) - 1023 - 52;
+    vluint64_t mantissa = (q & VL_MASK_Q(52)) | (1ULL << 52);
    vluint64_t out = 0;
    if (lsb < 0) {
        out = mantissa >> -lsb;
@@ -2385,8 +2441,8 @@ static inline WDataOutP VL_RTOIROUND_W_D(int obits, WDataOutP owp, double lhs) V
    VL_ZERO_W(obits, owp);
    if (lhs == 0.0) return owp;
    QData q = VL_CVT_Q_D(lhs);
-    int lsb = static_cast<int>((q >> VL_ULL(52)) & VL_MASK_Q(11)) - 1023 - 52;
-    vluint64_t mantissa = (q & VL_MASK_Q(52)) | (VL_ULL(1) << 52);
+    int lsb = static_cast<int>((q >> 52ULL) & VL_MASK_Q(11)) - 1023 - 52;
+    vluint64_t mantissa = (q & VL_MASK_Q(52)) | (1ULL << 52);
    if (lsb < 0) {
        VL_SET_WQ(owp, mantissa >> -lsb);
    } else if (lsb < obits) {
@@ -2505,25 +2561,25 @@ static inline WDataOutP VL_CONSTHI_W_1X(int obits, int lsb, WDataOutP obase,
                                        EData d0) VL_MT_SAFE {
    WDataOutP o = obase + VL_WORDS_I(lsb);
    o[0] = d0;
-    _END(obits,1);
+    _END(obits, VL_WORDS_I(lsb) + 1);
 }
 static inline WDataOutP VL_CONSTHI_W_2X(int obits, int lsb, WDataOutP obase,
                                        EData d1, EData d0) VL_MT_SAFE {
    WDataOutP o = obase + VL_WORDS_I(lsb);
    o[0] = d0;  o[1] = d1;
-    _END(obits,2);
+    _END(obits, VL_WORDS_I(lsb) + 2);
 }
 static inline WDataOutP VL_CONSTHI_W_3X(int obits, int lsb, WDataOutP obase,
                                        EData d2, EData d1, EData d0) VL_MT_SAFE {
    WDataOutP o = obase + VL_WORDS_I(lsb);
    o[0] = d0;  o[1] = d1;  o[2] = d2;
-    _END(obits,3);
+    _END(obits, VL_WORDS_I(lsb) + 3);
 }
 static inline WDataOutP VL_CONSTHI_W_4X(int obits, int lsb, WDataOutP obase,
                                        EData d3, EData d2, EData d1, EData d0) VL_MT_SAFE {
    WDataOutP o = obase + VL_WORDS_I(lsb);
    o[0] = d0;  o[1] = d1;  o[2] = d2;  o[3] = d3;
-    _END(obits,4);
+    _END(obits, VL_WORDS_I(lsb) + 4);
 }
 static inline WDataOutP VL_CONSTHI_W_5X(int obits, int lsb, WDataOutP obase,
                                        EData d4,
@@ -2531,7 +2587,7 @@ static inline WDataOutP VL_CONSTHI_W_5X(int obits, int lsb, WDataOutP obase,
    WDataOutP o = obase + VL_WORDS_I(lsb);
    o[0] = d0;  o[1] = d1;  o[2] = d2;  o[3] = d3;
    o[4] = d4;
-    _END(obits,5);
+    _END(obits, VL_WORDS_I(lsb) + 5);
 }
 static inline WDataOutP VL_CONSTHI_W_6X(int obits, int lsb, WDataOutP obase,
                                        EData d5, EData d4,
@@ -2539,7 +2595,7 @@ static inline WDataOutP VL_CONSTHI_W_6X(int obits, int lsb, WDataOutP obase,
    WDataOutP o = obase + VL_WORDS_I(lsb);
    o[0] = d0;  o[1] = d1;  o[2] = d2;  o[3] = d3;
    o[4] = d4;  o[5] = d5;
-    _END(obits,6);
+    _END(obits, VL_WORDS_I(lsb) + 6);
 }
 static inline WDataOutP VL_CONSTHI_W_7X(int obits, int lsb, WDataOutP obase,
                                        EData d6, EData d5, EData d4,
@@ -2547,7 +2603,7 @@ static inline WDataOutP VL_CONSTHI_W_7X(int obits, int lsb, WDataOutP obase,
    WDataOutP o = obase + VL_WORDS_I(lsb);
    o[0] = d0;  o[1] = d1;  o[2] = d2;  o[3] = d3;
    o[4] = d4;  o[5] = d5;  o[6] = d6;
-    _END(obits,7);
+    _END(obits, VL_WORDS_I(lsb) + 7);
 }
 static inline WDataOutP VL_CONSTHI_W_8X(int obits, int lsb, WDataOutP obase,
                                        EData d7, EData d6, EData d5, EData d4,
@@ -2555,7 +2611,7 @@ static inline WDataOutP VL_CONSTHI_W_8X(int obits, int lsb, WDataOutP obase,
    WDataOutP o = obase + VL_WORDS_I(lsb);
    o[0] = d0;  o[1] = d1;  o[2] = d2;  o[3] = d3;
    o[4] = d4;  o[5] = d5;  o[6] = d6;  o[7] = d7;
-    _END(obits,8);
+    _END(obits, VL_WORDS_I(lsb) + 8);
 }

 #undef _END
@@ -84,27 +84,29 @@ CPPFLAGS += $(VM_USER_CFLAGS)
 LDFLAGS  += $(VM_USER_LDFLAGS)
 LDLIBS   += $(VM_USER_LDLIBS)

-# See the benchmarking section of bin/verilator.
-# Support class optimizations.  This includes the tracing and symbol table.
-# SystemC takes minutes to optimize, thus it is off by default.
-#OPT_SLOW =
-# Fast path optimizations.  Most time is spent in these classes.
-#OPT_FAST = -Os -fstrict-aliasing
-#OPT_FAST = -O
-#OPT_FAST =
+######################################################################
+# Optimization control.

-#######################################################################
-##### Aggregates
+# See also the BENCHMARKING & OPTIMIZATION section of the manual.

-VM_CLASSES += $(VM_CLASSES_FAST) $(VM_CLASSES_SLOW)
-VM_SUPPORT += $(VM_SUPPORT_FAST) $(VM_SUPPORT_SLOW)
+# Optimization flags for non performance-critical/rarely executed code.
+# No optimization by default, which improves compilation speed.
+OPT_SLOW =
+# Optimization for performance critical/hot code. Most time is spent in these
+# routines. Optimizing by default for improved execution speed.
+OPT_FAST = -Os
+# Optimization applied to the common run-time library used by verilated models.
+# For compatibility this is called OPT_GLOBAL even though it only applies to
+# files in the run-time library. Normally there should be no need for the user
+# to change this as the library is small, but can have significant speed impact.
+OPT_GLOBAL = -Os

 #######################################################################
 ##### SystemC builds

 ifeq ($(VM_SC),1)
-  CPPFLAGS += $(SYSTEMC_CXX_FLAGS) -I$(SYSTEMC_INCLUDE)
-  LDFLAGS  += $(SYSTEMC_CXX_FLAGS) -L$(SYSTEMC_LIBDIR)
+  CPPFLAGS += $(SYSTEMC_CXX_FLAGS) $(addprefix -I, $(SYSTEMC_INCLUDE))
+  LDFLAGS  += $(SYSTEMC_CXX_FLAGS) $(addprefix -L, $(SYSTEMC_LIBDIR))
  SC_LIBS   = -lsystemc
 ifneq ($(wildcard $(SYSTEMC_LIBDIR)/*numeric_bit*),)
  # Systemc 1.2.1beta
@@ -163,58 +165,79 @@ ifneq ($(VK_LIBS_THREADED),0)
 endif

 #######################################################################
-##### Stub
+### Aggregates

-preproc:
+VM_FAST += $(VM_CLASSES_FAST) $(VM_SUPPORT_FAST)
+VM_SLOW += $(VM_CLASSES_SLOW) $(VM_SUPPORT_SLOW)

 #######################################################################
-# Overall Objects Linking
+### Overall Objects Linking

-VK_CLASSES_FAST_CPP = $(addsuffix .cpp, $(VM_CLASSES_FAST))
-VK_CLASSES_SLOW_CPP = $(addsuffix .cpp, $(VM_CLASSES_SLOW))
-
-VK_SUPPORT_FAST_CPP = $(addsuffix .cpp, $(VM_SUPPORT_FAST))
-VK_SUPPORT_SLOW_CPP = $(addsuffix .cpp, $(VM_SUPPORT_SLOW))
+VK_FAST_OBJS = $(addsuffix .o, $(VM_FAST))
+VK_SLOW_OBJS = $(addsuffix .o, $(VM_SLOW))

 VK_USER_OBJS   = $(addsuffix .o, $(VM_USER_CLASSES))

+# Note VM_GLOBAL_FAST and VM_GLOBAL_SLOW holds the files required from the
+# run-time library. In practice everything is actually in VM_GLOBAL_FAST,
+# but keeping the distinction for compatibility for now.
 VK_GLOBAL_OBJS = $(addsuffix .o, $(VM_GLOBAL_FAST) $(VM_GLOBAL_SLOW))

 ifneq ($(VM_PARALLEL_BUILDS),1)
-  # Fast building, all .cpp's in one fell swoop
-  # This saves about 5 sec per module, but can be slower if only a little changes
-  VK_OBJS += $(VM_PREFIX)__ALLfast.o   $(VM_PREFIX)__ALLslow.o
-  all_cpp:   $(VM_PREFIX)__ALLfast.cpp $(VM_PREFIX)__ALLslow.cpp
-  $(VM_PREFIX)__ALLfast.cpp: $(VK_CLASSES_FAST_CPP) $(VK_SUPPORT_FAST_CPP)
-	$(VERILATOR_INCLUDER) -DVL_INCLUDE_OPT=include $^ > $@
-  $(VM_PREFIX)__ALLslow.cpp: $(VK_CLASSES_SLOW_CPP) $(VK_SUPPORT_SLOW_CPP)
+  # Fast build for small designs: All .cpp files in one fell swoop. This
+  # saves total compute, but can be slower if only a little changes. It is
+  # also a lot slower for medium to large designs when the speed of the C
+  # compiler dominates, which in this mode is not parallelizable.
+
+  VK_OBJS += $(VM_PREFIX)__ALL.o
+  $(VM_PREFIX)__ALL.cpp: $(addsuffix .cpp, $(VM_FAST) $(VM_SLOW))
 	$(VERILATOR_INCLUDER) -DVL_INCLUDE_OPT=include $^ > $@
+  all_cpp: $(VM_PREFIX)__ALL.cpp
 else
-  #Slow way of building... Each .cpp file by itself
-  VK_OBJS += $(addsuffix .o, $(VM_CLASSES) $(VM_SUPPORT))
+  # Parallel build: Each .cpp file by itself. This can be somewhat slower for
+  # very small designs and examples, but is a lot faster for large designs.
+
+  VK_OBJS += $(VK_FAST_OBJS) $(VK_SLOW_OBJS)
 endif

-$(VM_PREFIX)__ALL.a: $(VK_OBJS)
-	$(AR) -cr $@ $^
-	$(RANLIB) $@
+# When archiving just objects (.o), single $(AR) run is enough.
+# When merging objects (.o) and archives (.a), the following steps are taken.
+#   1. Extract object files from .a
+#   2. Create a new archive from extracted .o and given .o
+%.a:
+	@echo "Archive $(AR) -cr $@ $^"
+	@if test $(words $(filter %.a,$^)) -eq 0; then \
+		$(AR) -cr $@ $^; \
+		$(RANLIB) $@; \
+	else \
+		$(RM) -rf $*__tmpdir; \
+		for archive in $(filter %.a,$^); do \
+			mkdir -p $*__tmpdir/$$(basename $${archive}); \
+			cd $*__tmpdir/$$(basename $${archive}); \
+			$(AR) -x ../../$${archive}; \
+			cd ../..; \
+		done; \
+		$(AR) -cr $@ $(filter %.o,$^) $*__tmpdir/*/*.o; \
+		$(RM) -rf $*__tmpdir; \
+	fi
+
+$(VM_PREFIX)__ALL.a: $(VK_OBJS) $(VM_HIER_LIBS)
+

 ######################################################################
 ### Compile rules

 ifneq ($(VM_DEFAULT_RULES),0)
-$(VM_PREFIX)__ALLfast.o: $(VM_PREFIX)__ALLfast.cpp
-	$(OBJCACHE) $(CXX) $(CXXFLAGS) $(CPPFLAGS) $(OPT_FAST) -c -o $@ $<
-
-$(VM_PREFIX)__ALLslow.o: $(VM_PREFIX)__ALLslow.cpp
-	$(OBJCACHE) $(CXX) $(CXXFLAGS) $(CPPFLAGS) $(OPT_SLOW) -c -o $@ $<
-
-# VM_GLOBAL_FAST files including verilated.o use this rule
+# Anything not in $(VK_SLOW_OBJS) or $(VK_GLOBAL_OBJS), including verilated.o
+# and user files passed on the Verilator command line use this rule.
 %.o: %.cpp
 	$(OBJCACHE) $(CXX) $(CXXFLAGS) $(CPPFLAGS) $(OPT_FAST) -c -o $@ $<

-%__Slow.o: %__Slow.cpp
+$(VK_SLOW_OBJS): %.o: %.cpp
 	$(OBJCACHE) $(CXX) $(CXXFLAGS) $(CPPFLAGS) $(OPT_SLOW) -c -o $@ $<

+$(VK_GLOBAL_OBJS): %.o: %.cpp
+	$(OBJCACHE) $(CXX) $(CXXFLAGS) $(CPPFLAGS) $(OPT_GLOBAL) -c -o $@ $<
 endif

 #Default rule embedded in make:
@@ -70,15 +70,15 @@ private:
 public:
    // METHODS
    // cppcheck-suppress truncLongCastReturn
-    virtual vluint64_t count() const VL_OVERRIDE { return *m_countp; }
-    virtual void zero() const VL_OVERRIDE { *m_countp = 0; }
+    virtual vluint64_t count() const override { return *m_countp; }
+    virtual void zero() const override { *m_countp = 0; }
    // CONSTRUCTORS
    // cppcheck-suppress noExplicitConstructor
    explicit VerilatedCoverItemSpec(T* countp)
-        : m_countp(countp) {
+        : m_countp{countp} {
        *m_countp = 0;
    }
-    virtual ~VerilatedCoverItemSpec() VL_OVERRIDE {}
+    virtual ~VerilatedCoverItemSpec() override {}
 };

 //=============================================================================
@@ -94,23 +94,18 @@ private:
    typedef std::map<int, std::string> IndexValueMap;
    typedef std::deque<VerilatedCovImpItem*> ItemList;

-private:
    // MEMBERS
    VerilatedMutex m_mutex;  ///< Protects all members
    ValueIndexMap m_valueIndexes VL_GUARDED_BY(m_mutex);  ///< Unique arbitrary value for values
    IndexValueMap m_indexValues VL_GUARDED_BY(m_mutex);  ///< Unique arbitrary value for keys
    ItemList m_items VL_GUARDED_BY(m_mutex);  ///< List of all items

-    VerilatedCovImpItem* m_insertp VL_GUARDED_BY(m_mutex);  ///< Item about to insert
-    const char* m_insertFilenamep VL_GUARDED_BY(m_mutex);  ///< Filename about to insert
-    int m_insertLineno VL_GUARDED_BY(m_mutex);  ///< Line number about to insert
+    VerilatedCovImpItem* m_insertp VL_GUARDED_BY(m_mutex) = nullptr;  ///< Item about to insert
+    const char* m_insertFilenamep VL_GUARDED_BY(m_mutex) = nullptr;  ///< Filename about to insert
+    int m_insertLineno VL_GUARDED_BY(m_mutex) = 0;  ///< Line number about to insert

    // CONSTRUCTORS
-    VerilatedCovImp() {
-        m_insertp = NULL;
-        m_insertFilenamep = NULL;
-        m_insertLineno = 0;
-    }
+    VerilatedCovImp() {}
    VL_UNCOPYABLE(VerilatedCovImp);

 public:
@@ -124,7 +119,7 @@ private:
    // PRIVATE METHODS
    int valueIndex(const std::string& value) VL_REQUIRES(m_mutex) {
        static int nextIndex = KEY_UNDEF + 1;
-        ValueIndexMap::iterator iter = m_valueIndexes.find(value);
+        const auto iter = m_valueIndexes.find(value);
        if (iter != m_valueIndexes.end()) return iter->second;
        nextIndex++;
        assert(nextIndex > 0);  // Didn't rollover
@@ -221,26 +216,22 @@ private:
    }
    static void selftest() VL_MT_SAFE {
        // Little selftest
-#define VL_CST_CHECK(got, exp) \
+#define SELF_CHECK(got, exp) \
    do { \
        if ((got) != (exp)) VL_FATAL_MT(__FILE__, __LINE__, "", "%Error: selftest\n"); \
    } while (0)
-
-        VL_CST_CHECK(combineHier("a.b.c", "a.b.c"), "a.b.c");
-        VL_CST_CHECK(combineHier("a.b.c", "a.b"), "a.b*");
-        VL_CST_CHECK(combineHier("a.x.c", "a.y.c"), "a.*.c");
-        VL_CST_CHECK(combineHier("a.z.z.z.c", "a.b.c"), "a.*.c");
-        VL_CST_CHECK(combineHier("z", "a"), "*");
-        VL_CST_CHECK(combineHier("q.a", "q.b"), "q.*");
-        VL_CST_CHECK(combineHier("q.za", "q.zb"), "q.z*");
-        VL_CST_CHECK(combineHier("1.2.3.a", "9.8.7.a"), "*.a");
-#undef VL_CST_CHECK
+        SELF_CHECK(combineHier("a.b.c", "a.b.c"), "a.b.c");
+        SELF_CHECK(combineHier("a.b.c", "a.b"), "a.b*");
+        SELF_CHECK(combineHier("a.x.c", "a.y.c"), "a.*.c");
+        SELF_CHECK(combineHier("a.z.z.z.c", "a.b.c"), "a.*.c");
+        SELF_CHECK(combineHier("z", "a"), "*");
+        SELF_CHECK(combineHier("q.a", "q.b"), "q.*");
+        SELF_CHECK(combineHier("q.za", "q.zb"), "q.z*");
+        SELF_CHECK(combineHier("1.2.3.a", "9.8.7.a"), "*.a");
+#undef SELF_CHECK
    }
    void clearGuts() VL_REQUIRES(m_mutex) {
-        for (ItemList::const_iterator it = m_items.begin(); it != m_items.end(); ++it) {
-            VerilatedCovImpItem* itemp = *(it);
-            VL_DO_DANGLING(delete itemp, itemp);
-        }
+        for (const auto& itemp : m_items) VL_DO_DANGLING(delete itemp, itemp);
        m_items.clear();
        m_indexValues.clear();
        m_valueIndexes.clear();
@@ -250,16 +241,15 @@ public:
    // PUBLIC METHODS
    void clear() VL_EXCLUDES(m_mutex) {
        Verilated::quiesce();
-        VerilatedLockGuard lock(m_mutex);
+        const VerilatedLockGuard lock(m_mutex);
        clearGuts();
    }
    void clearNonMatch(const char* matchp) VL_EXCLUDES(m_mutex) {
        Verilated::quiesce();
-        VerilatedLockGuard lock(m_mutex);
+        const VerilatedLockGuard lock(m_mutex);
        if (matchp && matchp[0]) {
            ItemList newlist;
-            for (ItemList::iterator it = m_items.begin(); it != m_items.end(); ++it) {
-                VerilatedCovImpItem* itemp = *(it);
+            for (const auto& itemp : m_items) {
                if (!itemMatchesString(itemp, matchp)) {
                    VL_DO_DANGLING(delete itemp, itemp);
                } else {
@@ -271,25 +261,23 @@ public:
    }
    void zero() VL_EXCLUDES(m_mutex) {
        Verilated::quiesce();
-        VerilatedLockGuard lock(m_mutex);
-        for (ItemList::const_iterator it = m_items.begin(); it != m_items.end(); ++it) {
-            (*it)->zero();
-        }
+        const VerilatedLockGuard lock(m_mutex);
+        for (const auto& itemp : m_items) itemp->zero();
    }

    // We assume there's always call to i/f/p in that order
    void inserti(VerilatedCovImpItem* itemp) VL_EXCLUDES(m_mutex) {
-        VerilatedLockGuard lock(m_mutex);
+        const VerilatedLockGuard lock(m_mutex);
        assert(!m_insertp);
        m_insertp = itemp;
    }
    void insertf(const char* filenamep, int lineno) VL_EXCLUDES(m_mutex) {
-        VerilatedLockGuard lock(m_mutex);
+        const VerilatedLockGuard lock(m_mutex);
        m_insertFilenamep = filenamep;
        m_insertLineno = lineno;
    }
    void insertp(const char* ckeyps[MAX_KEYS], const char* valps[MAX_KEYS]) VL_EXCLUDES(m_mutex) {
-        VerilatedLockGuard lock(m_mutex);
+        const VerilatedLockGuard lock(m_mutex);
        assert(m_insertp);
        // First two key/vals are filename
        ckeyps[0] = "filename";
@@ -332,22 +320,22 @@ public:
                m_insertp->m_keys[addKeynum] = valueIndex(key);
                m_insertp->m_vals[addKeynum] = valueIndex(val);
                addKeynum++;
-                if (!legalKey(key)) {
+                if (VL_UNCOVERABLE(!legalKey(key))) {
                    std::string msg
                        = ("%Error: Coverage keys of one character, or letter+digit are illegal: "
-                           + key);
+                           + key);  // LCOV_EXCL_LINE
                    VL_FATAL_MT("", 0, "", msg.c_str());
                }
            }
        }
        m_items.push_back(m_insertp);
        // Prepare for next
-        m_insertp = NULL;
+        m_insertp = nullptr;
    }

    void write(const char* filename) VL_EXCLUDES(m_mutex) {
        Verilated::quiesce();
-        VerilatedLockGuard lock(m_mutex);
+        const VerilatedLockGuard lock(m_mutex);
 #ifndef VM_COVERAGE
        VL_FATAL_MT("", 0, "", "%Error: Called VerilatedCov::write when VM_COVERAGE disabled\n");
 #endif
@@ -362,10 +350,9 @@ public:
        os << "# SystemC::Coverage-3\n";

        // Build list of events; totalize if collapsing hierarchy
-        typedef std::map<std::string, std::pair<std::string, vluint64_t> > EventMap;
+        typedef std::map<std::string, std::pair<std::string, vluint64_t>> EventMap;
        EventMap eventCounts;
-        for (ItemList::iterator it = m_items.begin(); it != m_items.end(); ++it) {
-            VerilatedCovImpItem* itemp = *(it);
+        for (const auto& itemp : m_items) {
            std::string name;
            std::string hier;
            bool per_instance = false;
@@ -396,7 +383,7 @@ public:
            // inefficient)

            // Find or insert the named event
-            EventMap::iterator cit = eventCounts.find(name);
+            const auto cit = eventCounts.find(name);
            if (cit != eventCounts.end()) {
                const std::string& oldhier = cit->second.first;
                cit->second.second += itemp->count();
@@ -407,11 +394,11 @@ public:
        }

        // Output body
-        for (EventMap::const_iterator it = eventCounts.begin(); it != eventCounts.end(); ++it) {
+        for (const auto& i : eventCounts) {
            os << "C '" << std::dec;
-            os << it->first;
-            if (!it->second.first.empty()) os << keyValueFormatter(VL_CIK_HIER, it->second.first);
-            os << "' " << it->second.second;
+            os << i.first;
+            if (!i.second.first.empty()) os << keyValueFormatter(VL_CIK_HIER, i.second.first);
+            os << "' " << i.second.second;
            os << std::endl;
        }
    }
@@ -447,15 +434,15 @@ void VerilatedCov::_insertp(A(0), A(1), A(2), A(3), A(4), A(5), A(6), A(7), A(8)
                            A(21), A(22), A(23), A(24), A(25), A(26), A(27), A(28),
                            A(29)) VL_MT_SAFE {
    const char* keyps[VerilatedCovImpBase::MAX_KEYS]
-        = {NULL,  NULL,  NULL,  // filename,lineno,page
-           key0,  key1,  key2,  key3,  key4,  key5,  key6,  key7,  key8,  key9,
-           key10, key11, key12, key13, key14, key15, key16, key17, key18, key19,
-           key20, key21, key22, key23, key24, key25, key26, key27, key28, key29};
+        = {nullptr, nullptr, nullptr,  // filename,lineno,page
+           key0,    key1,    key2,    key3,  key4,  key5,  key6,  key7,  key8,  key9,
+           key10,   key11,   key12,   key13, key14, key15, key16, key17, key18, key19,
+           key20,   key21,   key22,   key23, key24, key25, key26, key27, key28, key29};
    const char* valps[VerilatedCovImpBase::MAX_KEYS]
-        = {NULL,   NULL,   NULL,  // filename,lineno,page
-           valp0,  valp1,  valp2,  valp3,  valp4,  valp5,  valp6,  valp7,  valp8,  valp9,
-           valp10, valp11, valp12, valp13, valp14, valp15, valp16, valp17, valp18, valp19,
-           valp20, valp21, valp22, valp23, valp24, valp25, valp26, valp27, valp28, valp29};
+        = {nullptr, nullptr, nullptr,  // filename,lineno,page
+           valp0,   valp1,   valp2,   valp3,  valp4,  valp5,  valp6,  valp7,  valp8,  valp9,
+           valp10,  valp11,  valp12,  valp13, valp14, valp15, valp16, valp17, valp18, valp19,
+           valp20,  valp21,  valp22,  valp23, valp24, valp25, valp26, valp27, valp28, valp29};
    VerilatedCovImp::imp().insertp(keyps, valps);
 }

@@ -475,11 +462,11 @@ void VerilatedCov::_insertp(A(0), A(1), A(2), A(3), A(4), A(5), A(6), A(7), A(8)
 }
 // Backward compatibility for Verilator
 void VerilatedCov::_insertp(A(0), A(1), K(2), int val2, K(3), int val3, K(4),
-                            const std::string& val4, A(5), A(6)) VL_MT_SAFE {
+                            const std::string& val4, A(5), A(6), A(7)) VL_MT_SAFE {
    std::string val2str = vlCovCvtToStr(val2);
    std::string val3str = vlCovCvtToStr(val3);
    _insertp(C(0), C(1), key2, val2str.c_str(), key3, val3str.c_str(), key4, val4.c_str(), C(5),
-             C(6), N(7), N(8), N(9), N(10), N(11), N(12), N(13), N(14), N(15), N(16), N(17), N(18),
+             C(6), C(7), N(8), N(9), N(10), N(11), N(12), N(13), N(14), N(15), N(16), N(17), N(18),
             N(19), N(20), N(21), N(22), N(23), N(24), N(25), N(26), N(27), N(28), N(29));
 }
 #undef A
@@ -112,7 +112,7 @@ public:
    // there's not much more gain in having a version for each number of args.
 #define K(n) const char* key##n
 #define A(n) const char *key##n, const char *valp##n  // Argument list
-#define D(n) const char *key##n = NULL, const char *valp##n = NULL  // Argument list
+#define D(n) const char *key##n = nullptr, const char *valp##n = nullptr  // Argument list
    static void _insertp(D(0), D(1), D(2), D(3), D(4), D(5), D(6), D(7), D(8), D(9));
    static void _insertp(A(0), A(1), A(2), A(3), A(4), A(5), A(6), A(7), A(8), A(9), A(10), D(11),
                         D(12), D(13), D(14), D(15), D(16), D(17), D(18), D(19));
@@ -121,7 +121,7 @@ public:
                         D(22), D(23), D(24), D(25), D(26), D(27), D(28), D(29));
    // Backward compatibility for Verilator
    static void _insertp(A(0), A(1), K(2), int val2, K(3), int val3, K(4), const std::string& val4,
-                         A(5), A(6));
+                         A(5), A(6), A(7));

 #undef K
 #undef A
@@ -38,6 +38,7 @@ VLCOVGEN_ITEM("name=>'filename',    short=>'f',  group=>1, default=>undef, descr
 VLCOVGEN_ITEM("name=>'groupdesc',   short=>'d',  group=>1, default=>'',    descr=>'Description of the covergroup this item belongs to'")
 VLCOVGEN_ITEM("name=>'groupname',   short=>'g',  group=>1, default=>'',    descr=>'Group name of the covergroup this item belongs to'")
 VLCOVGEN_ITEM("name=>'groupcmt',    short=>'O',  group=>1, default=>'',    ")
+VLCOVGEN_ITEM("name=>'linescov',    short=>'S',  group=>1, default=>'',    descr=>'List of comma-separated lines covered'")
 VLCOVGEN_ITEM("name=>'per_instance',short=>'P',  group=>1, default=>0,     descr=>'True if every hierarchy is independently counted; otherwise all hierarchies will be combined into a single count'")
 VLCOVGEN_ITEM("name=>'row0_name',   short=>'R0', group=>1, default=>undef, descr=>'The row title for the header line of this row'")
 VLCOVGEN_ITEM("name=>'row1_name',   short=>'R1', group=>1, default=>undef, ")
@@ -80,6 +81,7 @@ VLCOVGEN_ITEM("name=>'weight',      short=>'w',  group=>0, default=>undef, descr
 #define VL_CIK_HIER "h"
 #define VL_CIK_LIMIT "L"
 #define VL_CIK_LINENO "l"
+#define VL_CIK_LINESCOV "S"
 #define VL_CIK_PER_INSTANCE "P"
 #define VL_CIK_ROW0 "r0"
 #define VL_CIK_ROW0_NAME "R0"
@@ -121,6 +123,7 @@ public:
        if (key == "hier") return VL_CIK_HIER;
        if (key == "limit") return VL_CIK_LIMIT;
        if (key == "lineno") return VL_CIK_LINENO;
+        if (key == "linescov") return VL_CIK_LINESCOV;
        if (key == "per_instance") return VL_CIK_PER_INSTANCE;
        if (key == "row0") return VL_CIK_ROW0;
        if (key == "row0_name") return VL_CIK_ROW0_NAME;
@@ -47,7 +47,7 @@
 // Function requires a "context" in the import declaration
 #define _VL_SVDPI_CONTEXT_WARN() \
    _VL_SVDPI_WARN("%%Warning: DPI C Function called by Verilog DPI import with missing " \
-                   "'context' keyword.\n");
+                   "'context' keyword.\n")

 //======================================================================
 //======================================================================
@@ -181,7 +181,7 @@ void svPutPartselLogic(svLogicVecVal* dp, const svLogicVecVal s, int lbit, int w
 static inline const VerilatedDpiOpenVar* _vl_openhandle_varp(const svOpenArrayHandle h) {
    if (VL_UNLIKELY(!h)) {
        VL_FATAL_MT(__FILE__, __LINE__, "",
-                    "%%Error: DPI svOpenArrayHandle function called with NULL handle");
+                    "%%Error: DPI svOpenArrayHandle function called with nullptr handle");
    }
    const VerilatedDpiOpenVar* varp = reinterpret_cast<const VerilatedDpiOpenVar*>(h);
    if (VL_UNLIKELY(!varp->magicOk())) {
@@ -202,10 +202,10 @@ int svIncrement(const svOpenArrayHandle h, int d) { return _vl_openhandle_varp(h
 int svSize(const svOpenArrayHandle h, int d) { return _vl_openhandle_varp(h)->elements(d); }
 int svDimensions(const svOpenArrayHandle h) { return _vl_openhandle_varp(h)->udims(); }

-/// Return pointer to open array data, or NULL if not in IEEE standard C layout
+/// Return pointer to open array data, or nullptr if not in IEEE standard C layout
 void* svGetArrayPtr(const svOpenArrayHandle h) {
    const VerilatedDpiOpenVar* varp = _vl_openhandle_varp(h);
-    if (VL_UNLIKELY(!varp->isDpiStdLayout())) return NULL;
+    if (VL_UNLIKELY(!varp->isDpiStdLayout())) return nullptr;
    return varp->datap();
 }
 /// Return size of open array, or 0 if not in IEEE standard C layout
@@ -226,7 +226,7 @@ static void* _vl_sv_adjusted_datap(const VerilatedDpiOpenVar* varp, int nargs, i
        _VL_SVDPI_WARN("%%Warning: DPI svOpenArrayHandle function called on"
                       " %d dimensional array using %d dimensional function.\n",
                       varp->udims(), nargs);
-        return NULL;
+        return nullptr;
    }
    if (nargs >= 1) {
        datap = varp->datapAdjustIndex(datap, 1, indx1);
@@ -234,7 +234,7 @@ static void* _vl_sv_adjusted_datap(const VerilatedDpiOpenVar* varp, int nargs, i
            _VL_SVDPI_WARN("%%Warning: DPI svOpenArrayHandle function index 1 "
                           "out of bounds; %d outside [%d:%d].\n",
                           indx1, varp->left(1), varp->right(1));
-            return NULL;
+            return nullptr;
        }
    }
    if (nargs >= 2) {
@@ -243,7 +243,7 @@ static void* _vl_sv_adjusted_datap(const VerilatedDpiOpenVar* varp, int nargs, i
            _VL_SVDPI_WARN("%%Warning: DPI svOpenArrayHandle function index 2 "
                           "out of bounds; %d outside [%d:%d].\n",
                           indx2, varp->left(2), varp->right(2));
-            return NULL;
+            return nullptr;
        }
    }
    if (nargs >= 3) {
@@ -252,7 +252,7 @@ static void* _vl_sv_adjusted_datap(const VerilatedDpiOpenVar* varp, int nargs, i
            _VL_SVDPI_WARN("%%Warning: DPI svOpenArrayHandle function index 3 "
                           "out of bounds; %d outside [%d:%d].\n",
                           indx1, varp->left(3), varp->right(3));
-            return NULL;
+            return nullptr;
        }
    }
    return datap;
@@ -268,11 +268,11 @@ static int _vl_sv_adjusted_bit(const VerilatedDpiOpenVar* varp, int indx) {
    return indx - varp->low(0);
 }

-/// Return pointer to simulator open array element, or NULL if outside range
+/// Return pointer to simulator open array element, or nullptr if outside range
 static void* _vl_svGetArrElemPtr(const svOpenArrayHandle h, int nargs, int indx1, int indx2,
                                 int indx3) VL_MT_SAFE {
    const VerilatedDpiOpenVar* varp = _vl_openhandle_varp(h);
-    if (VL_UNLIKELY(!varp->isDpiStdLayout())) return NULL;
+    if (VL_UNLIKELY(!varp->isDpiStdLayout())) return nullptr;
    void* datap = _vl_sv_adjusted_datap(varp, nargs, indx1, indx2, indx3);
    return datap;
 }
@@ -416,7 +416,7 @@ static svBit _vl_svGetBitArrElem(const svOpenArrayHandle s, int nargs, int indx1
    case VLVT_UINT16: return (*(reinterpret_cast<SData*>(datap)) >> lsb) & 1;
    case VLVT_UINT32: return (*(reinterpret_cast<IData*>(datap)) >> lsb) & 1;
    case VLVT_UINT64:
-        return (*(reinterpret_cast<QData*>(datap)) >> static_cast<QData>(lsb)) & VL_ULL(1);
+        return (*(reinterpret_cast<QData*>(datap)) >> static_cast<QData>(lsb)) & 1ULL;
    case VLVT_WDATA: {
        WDataOutP wdatap = (reinterpret_cast<WDataOutP>(datap));
        return VL_BITRSHIFT_W(wdatap, lsb) & 1;
@@ -794,7 +794,7 @@ void svPutLogicArrElem3(const svOpenArrayHandle d, svLogic value, int indx1, int
 svScope svGetScope() {
    if (VL_UNLIKELY(!Verilated::dpiInContext())) {
        _VL_SVDPI_CONTEXT_WARN();
-        return NULL;
+        return nullptr;
    }
    // NOLINTNEXTLINE(google-readability-casting)
    return (svScope)(Verilated::dpiScope());
@@ -36,17 +36,12 @@
 #include "gtkwave/lz4.c"

 #include <algorithm>
-#include <cerrno>
-#include <ctime>
-#include <fcntl.h>
 #include <iterator>
 #include <sstream>
-#include <sys/stat.h>

 #if defined(_WIN32) && !defined(__MINGW32__) && !defined(__CYGWIN__)
 # include <io.h>
 #else
-# include <stdint.h>
 # include <unistd.h>
 #endif

@@ -63,14 +58,12 @@
 // VerilatedFst

 VerilatedFst::VerilatedFst(void* fst)
-    : m_fst(fst)
-    , m_symbolp(NULL)
-    , m_strbuf(NULL) {}
+    : m_fst{fst} {}

 VerilatedFst::~VerilatedFst() {
    if (m_fst) fstWriterClose(m_fst);
-    if (m_symbolp) VL_DO_CLEAR(delete[] m_symbolp, m_symbolp = NULL);
-    if (m_strbuf) VL_DO_CLEAR(delete[] m_strbuf, m_strbuf = NULL);
+    if (m_symbolp) VL_DO_CLEAR(delete[] m_symbolp, m_symbolp = nullptr);
+    if (m_strbuf) VL_DO_CLEAR(delete[] m_strbuf, m_strbuf = nullptr);
 }

 void VerilatedFst::open(const char* filename) VL_MT_UNSAFE {
@@ -87,7 +80,7 @@ void VerilatedFst::open(const char* filename) VL_MT_UNSAFE {
    VerilatedTrace<VerilatedFst>::traceInit();

    // Clear the scope stack
-    std::list<std::string>::iterator it = m_curScope.begin();
+    auto it = m_curScope.begin();
    while (it != m_curScope.end()) {
        fstWriterSetUpscope(m_fst);
        it = m_curScope.erase(it);
@@ -96,10 +89,7 @@ void VerilatedFst::open(const char* filename) VL_MT_UNSAFE {
    // convert m_code2symbol into an array for fast lookup
    if (!m_symbolp) {
        m_symbolp = new fstHandle[nextCode()];
-        for (Code2SymbolType::iterator it = m_code2symbol.begin(); it != m_code2symbol.end();
-             ++it) {
-            m_symbolp[it->first] = it->second;
-        }
+        for (const auto& i : m_code2symbol) m_symbolp[i.first] = i.second;
    }
    m_code2symbol.clear();

@@ -111,7 +101,7 @@ void VerilatedFst::close() {
    m_assertOne.check();
    VerilatedTrace<VerilatedFst>::close();
    fstWriterClose(m_fst);
-    m_fst = NULL;
+    m_fst = nullptr;
 }

 void VerilatedFst::flush() {
@@ -132,23 +122,23 @@ void VerilatedFst::declDTypeEnum(int dtypenum, const char* name, vluint32_t elem
    m_local2fstdtype[dtypenum] = enumNum;
 }

-void VerilatedFst::declSymbol(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
-                              fstVarType vartype, bool array, int arraynum, vluint32_t len,
-                              vluint32_t bits) {
+void VerilatedFst::declare(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
+                           fstVarType vartype, bool array, int arraynum, int msb, int lsb) {
+    const int bits = ((msb > lsb) ? (msb - lsb) : (lsb - msb)) + 1;
+
    VerilatedTrace<VerilatedFst>::declCode(code, bits, false);

-    std::pair<Code2SymbolType::iterator, bool> p
-        = m_code2symbol.insert(std::make_pair(code, static_cast<fstHandle>(NULL)));
    std::istringstream nameiss(name);
-    std::istream_iterator<std::string> beg(nameiss), end;
+    std::istream_iterator<std::string> beg(nameiss);
+    std::istream_iterator<std::string> end;
    std::list<std::string> tokens(beg, end);  // Split name
    std::string symbol_name(tokens.back());
    tokens.pop_back();  // Remove symbol name from hierarchy
    tokens.insert(tokens.begin(), moduleName());  // Add current module to the hierarchy

    // Find point where current and new scope diverge
-    std::list<std::string>::iterator cur_it = m_curScope.begin();
-    std::list<std::string>::iterator new_it = tokens.begin();
+    auto cur_it = m_curScope.begin();
+    auto new_it = tokens.begin();
    while (cur_it != m_curScope.end() && new_it != tokens.end()) {
        if (*cur_it != *new_it) break;
        ++cur_it;
@@ -163,7 +153,7 @@ void VerilatedFst::declSymbol(vluint32_t code, const char* name, int dtypenum, f

    // Follow the hierarchy of the new variable from the common scope point
    while (new_it != tokens.end()) {
-        fstWriterSetScope(m_fst, FST_ST_VCD_SCOPE, new_it->c_str(), NULL);
+        fstWriterSetScope(m_fst, FST_ST_VCD_SCOPE, new_it->c_str(), nullptr);
        m_curScope.push_back(*new_it);
        new_it = tokens.erase(new_it);
    }
@@ -177,40 +167,35 @@ void VerilatedFst::declSymbol(vluint32_t code, const char* name, int dtypenum, f
        fstEnumHandle enumNum = m_local2fstdtype[dtypenum];
        fstWriterEmitEnumTableRef(m_fst, enumNum);
    }
-    if (p.second) {  // New
-        p.first->second = fstWriterCreateVar(m_fst, vartype, vardir, len, name_str.c_str(), 0);
-        assert(p.first->second);
+
+    const auto it = vlstd::as_const(m_code2symbol).find(code);
+    if (it == m_code2symbol.end()) {  // New
+        m_code2symbol[code]
+            = fstWriterCreateVar(m_fst, vartype, vardir, bits, name_str.c_str(), 0);
    } else {  // Alias
-        fstWriterCreateVar(m_fst, vartype, vardir, len, name_str.c_str(), p.first->second);
+        fstWriterCreateVar(m_fst, vartype, vardir, bits, name_str.c_str(), it->second);
    }
 }

 void VerilatedFst::declBit(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
                           fstVarType vartype, bool array, int arraynum) {
-    declSymbol(code, name, dtypenum, vardir, vartype, array, arraynum, 1, 1);
+    declare(code, name, dtypenum, vardir, vartype, array, arraynum, 0, 0);
 }
 void VerilatedFst::declBus(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
                           fstVarType vartype, bool array, int arraynum, int msb, int lsb) {
-    declSymbol(code, name, dtypenum, vardir, vartype, array, arraynum, msb - lsb + 1,
-               msb - lsb + 1);
+    declare(code, name, dtypenum, vardir, vartype, array, arraynum, msb, lsb);
 }
 void VerilatedFst::declQuad(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
                            fstVarType vartype, bool array, int arraynum, int msb, int lsb) {
-    declSymbol(code, name, dtypenum, vardir, vartype, array, arraynum, msb - lsb + 1,
-               msb - lsb + 1);
+    declare(code, name, dtypenum, vardir, vartype, array, arraynum, msb, lsb);
 }
 void VerilatedFst::declArray(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
                             fstVarType vartype, bool array, int arraynum, int msb, int lsb) {
-    declSymbol(code, name, dtypenum, vardir, vartype, array, arraynum, msb - lsb + 1,
-               msb - lsb + 1);
-}
-void VerilatedFst::declFloat(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
-                             fstVarType vartype, bool array, int arraynum) {
-    declSymbol(code, name, dtypenum, vardir, vartype, array, arraynum, 1, 32);
+    declare(code, name, dtypenum, vardir, vartype, array, arraynum, msb, lsb);
 }
 void VerilatedFst::declDouble(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
                              fstVarType vartype, bool array, int arraynum) {
-    declSymbol(code, name, dtypenum, vardir, vartype, array, arraynum, 2, 64);
+    declare(code, name, dtypenum, vardir, vartype, array, arraynum, 63, 0);
 }

 // Note: emit* are only ever called from one place (full* in
@@ -266,11 +251,6 @@ void VerilatedFst::emitWData(vluint32_t code, const WData* newvalp, int bits) {
    fstWriterEmitValueChange(m_fst, m_symbolp[code], m_strbuf);
 }

-VL_ATTR_ALWINLINE
-void VerilatedFst::emitFloat(vluint32_t code, float newval) {
-    fstWriterEmitValueChange(m_fst, m_symbolp[code], &newval);
-}
-
 VL_ATTR_ALWINLINE
 void VerilatedFst::emitDouble(vluint32_t code, double newval) {
    fstWriterEmitValueChange(m_fst, m_symbolp[code], &newval);
@@ -50,24 +50,24 @@ private:
    Code2SymbolType m_code2symbol;
    Local2FstDtype m_local2fstdtype;
    std::list<std::string> m_curScope;
-    fstHandle* m_symbolp;  ///< same as m_code2symbol, but as an array
-    char* m_strbuf;  ///< String buffer long enough to hold maxBits() chars
+    fstHandle* m_symbolp = nullptr;  ///< same as m_code2symbol, but as an array
+    char* m_strbuf = nullptr;  ///< String buffer long enough to hold maxBits() chars

    // CONSTRUCTORS
    VL_UNCOPYABLE(VerilatedFst);
-    void declSymbol(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
-                    fstVarType vartype, bool array, int arraynum, vluint32_t len, vluint32_t bits);
+    void declare(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
+                 fstVarType vartype, bool array, int arraynum, int msb, int lsb);

 protected:
    //=========================================================================
    // Implementation of VerilatedTrace interface

    // Implementations of protected virtual methods for VerilatedTrace
-    void emitTimeChange(vluint64_t timeui) VL_OVERRIDE;
+    virtual void emitTimeChange(vluint64_t timeui) override;

    // Hooks called from VerilatedTrace
-    bool preFullDump() VL_OVERRIDE { return isOpen(); }
-    bool preChangeDump() VL_OVERRIDE { return isOpen(); }
+    virtual bool preFullDump() override { return isOpen(); }
+    virtual bool preChangeDump() override { return isOpen(); }

    // Implementations of duck-typed methods for VerilatedTrace. These are
    // called from only one place (namely full*) so always inline them.
@@ -77,14 +77,13 @@ protected:
    inline void emitIData(vluint32_t code, IData newval, int bits);
    inline void emitQData(vluint32_t code, QData newval, int bits);
    inline void emitWData(vluint32_t code, const WData* newvalp, int bits);
-    inline void emitFloat(vluint32_t code, float newval);
    inline void emitDouble(vluint32_t code, double newval);

 public:
    //=========================================================================
    // External interface to client code

-    explicit VerilatedFst(void* fst = NULL);
+    explicit VerilatedFst(void* fst = nullptr);
    ~VerilatedFst();

    /// Open the file; call isOpen() to see if errors
@@ -94,7 +93,7 @@ public:
    /// Flush any remaining data to this file
    void flush() VL_MT_UNSAFE;
    /// Is file open?
-    bool isOpen() const { return m_fst != NULL; }
+    bool isOpen() const { return m_fst != nullptr; }

    //=========================================================================
    // Internal interface to Verilator generated code
@@ -112,8 +111,6 @@ public:
                  fstVarType vartype, bool array, int arraynum, int msb, int lsb);
    void declArray(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
                   fstVarType vartype, bool array, int arraynum, int msb, int lsb);
-    void declFloat(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
-                   fstVarType vartype, bool array, int arraynum);
    void declDouble(vluint32_t code, const char* name, int dtypenum, fstVarDir vardir,
                    fstVarType vartype, bool array, int arraynum);
 };
@@ -138,8 +135,8 @@ class VerilatedFstC {
    VL_UNCOPYABLE(VerilatedFstC);

 public:
-    explicit VerilatedFstC(void* filep = NULL)
-        : m_sptrace(filep) {}
+    explicit VerilatedFstC(void* filep = nullptr)
+        : m_sptrace{filep} {}
    ~VerilatedFstC() { close(); }
    /// Routines can only be called from one thread; allow next call from different thread
    void changeThread() { spTrace()->changeThread(); }
@@ -55,28 +55,28 @@ class VlReadMem {
 public:
    VlReadMem(bool hex, int bits, const std::string& filename, QData start, QData end);
    ~VlReadMem();
-    bool isOpen() const { return m_fp != NULL; }
+    bool isOpen() const { return m_fp != nullptr; }
    int linenum() const { return m_linenum; }
    bool get(QData& addrr, std::string& valuer);
    void setData(void* valuep, const std::string& rhs);
 };

 class VlWriteMem {
+    bool m_hex;  // Hex format
    int m_bits;  // Bit width of values
    FILE* m_fp;  // File handle for filename
    QData m_addr;  // Next address to write
 public:
    VlWriteMem(bool hex, int bits, const std::string& filename, QData start, QData end);
    ~VlWriteMem();
-    bool isOpen() const { return m_fp != NULL; }
+    bool isOpen() const { return m_fp != nullptr; }
    void print(QData addr, bool addrstamp, const void* valuep);
 };

 //===================================================================
 // Verilog array container
-// Similar to std::array<WData, N>, but:
-//   1. Doesn't require C++11
-//   2. Lighter weight, only methods needed by Verilator, to help compile time.
+// Similar to std::array<WData, N>, but lighter weight, only methods needed
+// by Verilator, to help compile time.
 //
 // This is only used when we need an upper-level container and so can't
 // simply use a C style array (which is just a pointer).
@@ -145,21 +145,21 @@ public:
    int exists(const T_Key& index) const { return m_map.find(index) != m_map.end(); }
    // Return first element.  Verilog: function int first(ref index);
    int first(T_Key& indexr) const {
-        typename Map::const_iterator it = m_map.begin();
+        const auto it = m_map.cbegin();
        if (it == m_map.end()) return 0;
        indexr = it->first;
        return 1;
    }
    // Return last element.  Verilog: function int last(ref index)
    int last(T_Key& indexr) const {
-        typename Map::const_reverse_iterator it = m_map.rbegin();
+        const auto it = m_map.crbegin();
        if (it == m_map.rend()) return 0;
        indexr = it->first;
        return 1;
    }
    // Return next element. Verilog: function int next(ref index)
    int next(T_Key& indexr) const {
-        typename Map::const_iterator it = m_map.find(indexr);
+        auto it = m_map.find(indexr);
        if (VL_UNLIKELY(it == m_map.end())) return 0;
        ++it;
        if (VL_UNLIKELY(it == m_map.end())) return 0;
@@ -168,7 +168,7 @@ public:
    }
    // Return prev element. Verilog: function int prev(ref index)
    int prev(T_Key& indexr) const {
-        typename Map::const_iterator it = m_map.find(indexr);
+        auto it = m_map.find(indexr);
        if (VL_UNLIKELY(it == m_map.end())) return 0;
        if (VL_UNLIKELY(it == m_map.begin())) return 0;
        --it;
@@ -179,7 +179,7 @@ public:
    // Can't just overload operator[] or provide a "at" reference to set,
    // because we need to be able to insert only when the value is set
    T_Value& at(const T_Key& index) {
-        typename Map::iterator it = m_map.find(index);
+        const auto it = m_map.find(index);
        if (it == m_map.end()) {
            std::pair<typename Map::iterator, bool> pit
                = m_map.insert(std::make_pair(index, m_defaultValue));
@@ -189,7 +189,7 @@ public:
    }
    // Accessing. Verilog: v = assoc[index]
    const T_Value& at(const T_Key& index) const {
-        typename Map::iterator it = m_map.find(index);
+        const auto it = m_map.find(index);
        if (it == m_map.end()) {
            return m_defaultValue;
        } else {
@@ -204,8 +204,8 @@ public:
    std::string to_string() const {
        std::string out = "'{";
        std::string comma;
-        for (typename Map::const_iterator it = m_map.begin(); it != m_map.end(); ++it) {
-            out += comma + VL_TO_STRING(it->first) + ":" + VL_TO_STRING(it->second);
+        for (const auto& i : m_map) {
+            out += comma + VL_TO_STRING(i.first) + ":" + VL_TO_STRING(i.second);
            comma = ", ";
        }
        // Default not printed - maybe random init data
@@ -239,10 +239,9 @@ void VL_WRITEMEM_N(bool hex, int bits, const std::string& filename,
                   const VlAssocArray<T_Key, T_Value>& obj, QData start, QData end) VL_MT_SAFE {
    VlWriteMem wmem(hex, bits, filename, start, end);
    if (VL_UNLIKELY(!wmem.isOpen())) return;
-    for (typename VlAssocArray<T_Key, T_Value>::const_iterator it = obj.begin(); it != obj.end();
-         ++it) {
-        QData addr = it->first;
-        if (addr >= start && addr <= end) wmem.print(addr, true, &(it->second));
+    for (const auto& i : obj) {
+        QData addr = i.first;
+        if (addr >= start && addr <= end) wmem.print(addr, true, &(i.second));
    }
 }

@@ -361,8 +360,8 @@ public:
    std::string to_string() const {
        std::string out = "'{";
        std::string comma;
-        for (typename Deque::const_iterator it = m_deque.begin(); it != m_deque.end(); ++it) {
-            out += comma + VL_TO_STRING(*it);
+        for (const auto& i : m_deque) {
+            out += comma + VL_TO_STRING(i);
            comma = ", ";
        }
        return out + "} ";
@@ -379,13 +378,7 @@ template <class T_Value> std::string VL_TO_STRING(const VlQueue<T_Value>& obj) {
 // be protected by other means
 //

-// clang-format off
-#if (defined(_MSC_VER) && _MSC_VER >= 1900) || (__cplusplus >= 201103L)
-# define VlClassRef std::shared_ptr
-#else
-# define VlClassRef VlClassRef__SystemVerilog_class_support_requires_a_C11_or_newer_compiler
-#endif
-// clang-format on
+#define VlClassRef std::shared_ptr

 template <class T>  // T typically of type VlClassRef<x>
 inline T VL_NULL_CHECK(T t, const char* filename, int linenum) {
@@ -427,7 +420,8 @@ extern std::string VL_TOLOWER_NN(const std::string& ld);
 extern std::string VL_TOUPPER_NN(const std::string& ld);

 extern IData VL_FERROR_IN(IData fpi, std::string& outputr) VL_MT_SAFE;
-extern IData VL_FOPEN_NI(const std::string& filename, IData mode) VL_MT_SAFE;
+extern IData VL_FOPEN_NN(const std::string& filename, const std::string& mode) VL_MT_SAFE;
+extern IData VL_FOPEN_MCD_N(const std::string& filename) VL_MT_SAFE;
 extern void VL_READMEM_N(bool hex, int bits, QData depth, int array_lsb,
                         const std::string& filename, void* memp, QData start,
                         QData end) VL_MT_SAFE;
@@ -32,6 +32,7 @@
 #include <deque>
 #include <set>
 #include <vector>
+#include <numeric>
 #ifdef VL_THREADED
 # include <functional>
 # include <queue>
@@ -61,8 +62,8 @@ private:
 public:
    // CONSTRUCTORS
    VerilatedMsg(const std::function<void()>& cb)
-        : m_mtaskId(Verilated::mtaskId())
-        , m_cb(cb) {}
+        : m_mtaskId{Verilated::mtaskId()}
+        , m_cb{cb} {}
    ~VerilatedMsg() {}
    // METHODS
    vluint32_t mtaskId() const { return m_mtaskId; }
@@ -83,7 +84,7 @@ class VerilatedEvalMsgQueue {
 public:
    // CONSTRUCTORS
    VerilatedEvalMsgQueue()
-        : m_depth(0) {
+        : m_depth{0} {
        assert(atomic_is_lock_free(&m_depth));
    }
    ~VerilatedEvalMsgQueue() {}
@@ -95,7 +96,7 @@ public:
    // METHODS
    //// Add message to queue (called by producer)
    void post(const VerilatedMsg& msg) VL_EXCLUDES(m_mutex) {
-        VerilatedLockGuard lock(m_mutex);
+        const VerilatedLockGuard lock(m_mutex);
        m_queue.insert(msg);  // Pass by value to copy the message into queue
        ++m_depth;
    }
@@ -111,7 +112,7 @@ public:
            // Unfortunately to release the lock we need to copy the message
            // (Or have the message be a pointer, but then new/delete cost on each message)
            // We assume messages are small, so copy
-            auto it = m_queue.begin();
+            const auto it = m_queue.begin();
            const VerilatedMsg msg = *(it);
            m_queue.erase(it);
            m_mutex.unlock();
@@ -168,13 +169,31 @@ public:
 };
 #endif  // VL_THREADED

+// FILE* list constructed from a file-descriptor
+class VerilatedFpList {
+    FILE* m_fp[31];
+    std::size_t m_sz = 0;
+
+public:
+    typedef FILE* const* const_iterator;
+    explicit VerilatedFpList() {}
+    const_iterator begin() const { return m_fp; }
+    const_iterator end() const { return m_fp + m_sz; }
+    std::size_t size() const { return m_sz; }
+    std::size_t capacity() const { return 31; }
+    void push_back(FILE* fd) {
+        if (VL_LIKELY(size() < capacity())) m_fp[m_sz++] = fd;
+    }
+};
+
 //======================================================================
 // VerilatedImp

-class VerilatedImp {
+class VerilatedImpData {
    // Whole class is internal use only - Global information shared between verilated*.cpp files.
 protected:
    friend class Verilated;
+    friend class VerilatedImp;

    // TYPES
    typedef std::vector<std::string> ArgVec;
@@ -182,17 +201,13 @@ protected:
    typedef std::map<const char*, int, VerilatedCStrCmp> ExportNameMap;

    // MEMBERS
-    static VerilatedImp s_s;  ///< Static Singleton; One and only static this

    struct Serialized {  // All these members serialized/deserialized
-        int m_timeFormatUnits;  // $timeformat units
-        int m_timeFormatPrecision;  // $timeformat number of decimal places
-        int m_timeFormatWidth;  // $timeformat character width
+        int m_timeFormatUnits = UNITS_NONE;  // $timeformat units
+        int m_timeFormatPrecision = 0;  // $timeformat number of decimal places
+        int m_timeFormatWidth = 20;  // $timeformat character width
        enum { UNITS_NONE = 99 };  // Default based on precision
-        Serialized()
-            : m_timeFormatUnits(UNITS_NONE)
-            , m_timeFormatPrecision(0)
-            , m_timeFormatWidth(20) {}
+        Serialized() {}
        ~Serialized() {}
    } m_ser;

@@ -229,19 +244,41 @@ protected:
    VerilatedMutex m_fdMutex;  ///< Protect m_fdps, m_fdFree
    std::vector<FILE*> m_fdps VL_GUARDED_BY(m_fdMutex);  ///< File descriptors
    /// List of free descriptors (SLOW - FOPEN/CLOSE only)
-    std::deque<IData> m_fdFree VL_GUARDED_BY(m_fdMutex);
+    std::vector<IData> m_fdFree VL_GUARDED_BY(m_fdMutex);
+    // List of free descriptors in the MCT region [4, 32)
+    std::vector<IData> m_fdFreeMct VL_GUARDED_BY(m_fdMutex);
+
+    // CONSTRUCTORS
+    VerilatedImpData()
+        : m_argVecLoaded{false}
+        , m_exportNext{0} {
+
+        m_fdps.resize(31);
+        std::fill(m_fdps.begin(), m_fdps.end(), (FILE*)0);
+        m_fdFreeMct.resize(30);
+        for (std::size_t i = 0, id = 1; i < m_fdFreeMct.size(); ++i, ++id) { m_fdFreeMct[i] = id; }
+    }
+};
+
+class VerilatedImp {
+    // Whole class is internal use only - Global information shared between verilated*.cpp files.
+protected:
+    friend class Verilated;
+
+    // MEMBERS
+    union VerilatedImpU {  ///< Enclose in an union to call ctor/dtor manually
+        VerilatedImpData v;
+        VerilatedImpU() {}
+        ~VerilatedImpU() {}
+    };
+    static VerilatedImpU s_s;  ///< Static Singleton; One and only static this

 public:  // But only for verilated*.cpp
    // CONSTRUCTORS
-    VerilatedImp()
-        : m_argVecLoaded(false)
-        , m_exportNext(0) {
-        m_fdps.resize(3);
-        m_fdps[0] = stdin;
-        m_fdps[1] = stdout;
-        m_fdps[2] = stderr;
-    }
+    VerilatedImp() {}
    ~VerilatedImp() {}
+    static void setup();
+    static void teardown();

 private:
    VL_UNCOPYABLE(VerilatedImp);
@@ -253,28 +290,28 @@ public:

    // METHODS - arguments
 public:
-    static void commandArgs(int argc, const char** argv) VL_EXCLUDES(s_s.m_argMutex);
-    static void commandArgsAdd(int argc, const char** argv) VL_EXCLUDES(s_s.m_argMutex);
-    static std::string argPlusMatch(const char* prefixp) VL_EXCLUDES(s_s.m_argMutex) {
-        VerilatedLockGuard lock(s_s.m_argMutex);
+    static void commandArgs(int argc, const char** argv) VL_EXCLUDES(s_s.v.m_argMutex);
+    static void commandArgsAdd(int argc, const char** argv) VL_EXCLUDES(s_s.v.m_argMutex);
+    static std::string argPlusMatch(const char* prefixp) VL_EXCLUDES(s_s.v.m_argMutex) {
+        const VerilatedLockGuard lock(s_s.v.m_argMutex);
        // Note prefixp does not include the leading "+"
        size_t len = strlen(prefixp);
-        if (VL_UNLIKELY(!s_s.m_argVecLoaded)) {
-            s_s.m_argVecLoaded = true;  // Complain only once
+        if (VL_UNLIKELY(!s_s.v.m_argVecLoaded)) {
+            s_s.v.m_argVecLoaded = true;  // Complain only once
            VL_FATAL_MT("unknown", 0, "",
                        "%Error: Verilog called $test$plusargs or $value$plusargs without"
                        " testbench C first calling Verilated::commandArgs(argc,argv).");
        }
-        for (ArgVec::const_iterator it = s_s.m_argVec.begin(); it != s_s.m_argVec.end(); ++it) {
-            if ((*it)[0] == '+') {
-                if (0 == strncmp(prefixp, it->c_str() + 1, len)) return *it;
+        for (const auto& i : s_s.v.m_argVec) {
+            if (i[0] == '+') {
+                if (0 == strncmp(prefixp, i.c_str() + 1, len)) return i;
            }
        }
        return "";
    }

 private:
-    static void commandArgsAddGuts(int argc, const char** argv) VL_REQUIRES(s_s.m_argMutex);
+    static void commandArgsAddGuts(int argc, const char** argv) VL_REQUIRES(s_s.v.m_argMutex);
    static void commandArgVl(const std::string& arg);
    static bool commandArgVlValue(const std::string& arg, const std::string& prefix,
                                  std::string& valuer);
@@ -285,18 +322,18 @@ public:
    // There's often many more scopes than userdata's and thus having a ~48byte
    // per map overhead * N scopes would take much more space and cache thrashing.
    static inline void userInsert(const void* scopep, void* userKey, void* userData) VL_MT_SAFE {
-        VerilatedLockGuard lock(s_s.m_userMapMutex);
-        UserMap::iterator it = s_s.m_userMap.find(std::make_pair(scopep, userKey));
-        if (it != s_s.m_userMap.end()) {
+        const VerilatedLockGuard lock(s_s.v.m_userMapMutex);
+        const auto it = s_s.v.m_userMap.find(std::make_pair(scopep, userKey));
+        if (it != s_s.v.m_userMap.end()) {
            it->second = userData;
        } else {
-            s_s.m_userMap.insert(it, std::make_pair(std::make_pair(scopep, userKey), userData));
+            s_s.v.m_userMap.insert(it, std::make_pair(std::make_pair(scopep, userKey), userData));
        }
    }
    static inline void* userFind(const void* scopep, void* userKey) VL_MT_SAFE {
-        VerilatedLockGuard lock(s_s.m_userMapMutex);
-        UserMap::const_iterator it = s_s.m_userMap.find(std::make_pair(scopep, userKey));
-        if (VL_UNLIKELY(it == s_s.m_userMap.end())) return NULL;
+        const VerilatedLockGuard lock(s_s.v.m_userMapMutex);
+        const auto& it = vlstd::as_const(s_s.v.m_userMap).find(std::make_pair(scopep, userKey));
+        if (VL_UNLIKELY(it == s_s.v.m_userMap.end())) return nullptr;
        return it->second;
    }

@@ -304,25 +341,26 @@ private:
    /// Symbol table destruction cleans up the entries for each scope.
    static void userEraseScope(const VerilatedScope* scopep) VL_MT_SAFE {
        // Slow ok - called once/scope on destruction, so we simply iterate.
-        VerilatedLockGuard lock(s_s.m_userMapMutex);
-        for (UserMap::iterator it = s_s.m_userMap.begin(); it != s_s.m_userMap.end();) {
+        const VerilatedLockGuard lock(s_s.v.m_userMapMutex);
+        for (auto it = s_s.v.m_userMap.begin(); it != s_s.v.m_userMap.end();) {
            if (it->first.first == scopep) {
-                s_s.m_userMap.erase(it++);
+                s_s.v.m_userMap.erase(it++);
            } else {
                ++it;
            }
        }
    }
    static void userDump() VL_MT_SAFE {
-        VerilatedLockGuard lock(s_s.m_userMapMutex);  // Avoid it changing in middle of dump
+        const VerilatedLockGuard lock(
+            s_s.v.m_userMapMutex);  // Avoid it changing in middle of dump
        bool first = true;
-        for (UserMap::const_iterator it = s_s.m_userMap.begin(); it != s_s.m_userMap.end(); ++it) {
+        for (const auto& i : s_s.v.m_userMap) {
            if (first) {
                VL_PRINTF_MT("  userDump:\n");
                first = false;
            }
-            VL_PRINTF_MT("    DPI_USER_DATA scope %p key %p: %p\n", it->first.first,
-                         it->first.second, it->second);
+            VL_PRINTF_MT("    DPI_USER_DATA scope %p key %p: %p\n", i.first.first, i.first.second,
+                         i.second);
        }
    }

@@ -330,51 +368,50 @@ public:  // But only for verilated*.cpp
    // METHODS - scope name
    static void scopeInsert(const VerilatedScope* scopep) VL_MT_SAFE {
        // Slow ok - called once/scope at construction
-        VerilatedLockGuard lock(s_s.m_nameMutex);
-        VerilatedScopeNameMap::iterator it = s_s.m_nameMap.find(scopep->name());
-        if (it == s_s.m_nameMap.end()) {
-            s_s.m_nameMap.insert(it, std::make_pair(scopep->name(), scopep));
+        const VerilatedLockGuard lock(s_s.v.m_nameMutex);
+        const auto it = s_s.v.m_nameMap.find(scopep->name());
+        if (it == s_s.v.m_nameMap.end()) {
+            s_s.v.m_nameMap.insert(it, std::make_pair(scopep->name(), scopep));
        }
    }
    static inline const VerilatedScope* scopeFind(const char* namep) VL_MT_SAFE {
-        VerilatedLockGuard lock(s_s.m_nameMutex);
+        const VerilatedLockGuard lock(s_s.v.m_nameMutex);
        // If too slow, can assume this is only VL_MT_SAFE_POSINIT
-        VerilatedScopeNameMap::const_iterator it = s_s.m_nameMap.find(namep);
-        if (VL_UNLIKELY(it == s_s.m_nameMap.end())) return NULL;
+        const auto& it = s_s.v.m_nameMap.find(namep);
+        if (VL_UNLIKELY(it == s_s.v.m_nameMap.end())) return nullptr;
        return it->second;
    }
    static void scopeErase(const VerilatedScope* scopep) VL_MT_SAFE {
        // Slow ok - called once/scope at destruction
-        VerilatedLockGuard lock(s_s.m_nameMutex);
+        const VerilatedLockGuard lock(s_s.v.m_nameMutex);
        userEraseScope(scopep);
-        VerilatedScopeNameMap::iterator it = s_s.m_nameMap.find(scopep->name());
-        if (it != s_s.m_nameMap.end()) s_s.m_nameMap.erase(it);
+        const auto it = s_s.v.m_nameMap.find(scopep->name());
+        if (it != s_s.v.m_nameMap.end()) s_s.v.m_nameMap.erase(it);
    }
    static void scopesDump() VL_MT_SAFE {
-        VerilatedLockGuard lock(s_s.m_nameMutex);
+        const VerilatedLockGuard lock(s_s.v.m_nameMutex);
        VL_PRINTF_MT("  scopesDump:\n");
-        for (VerilatedScopeNameMap::const_iterator it = s_s.m_nameMap.begin();
-             it != s_s.m_nameMap.end(); ++it) {
-            const VerilatedScope* scopep = it->second;
+        for (const auto& i : s_s.v.m_nameMap) {
+            const VerilatedScope* scopep = i.second;
            scopep->scopeDump();
        }
        VL_PRINTF_MT("\n");
    }
    static const VerilatedScopeNameMap* scopeNameMap() VL_MT_SAFE_POSTINIT {
        // Thread save only assuming this is called only after model construction completed
-        return &s_s.m_nameMap;
+        return &s_s.v.m_nameMap;
    }

 public:  // But only for verilated*.cpp
    // METHODS - hierarchy
    static void hierarchyAdd(const VerilatedScope* fromp, const VerilatedScope* top) VL_MT_SAFE {
        // Slow ok - called at construction for VPI accessible elements
-        VerilatedLockGuard lock(s_s.m_hierMapMutex);
-        s_s.m_hierMap[fromp].push_back(top);
+        const VerilatedLockGuard lock(s_s.v.m_hierMapMutex);
+        s_s.v.m_hierMap[fromp].push_back(top);
    }
    static const VerilatedHierarchyMap* hierarchyMap() VL_MT_SAFE_POSTINIT {
        // Thread save only assuming this is called only after model construction completed
-        return &s_s.m_hierMap;
+        return &s_s.v.m_hierMap;
    }

 public:  // But only for verilated*.cpp
@@ -388,19 +425,19 @@ public:  // But only for verilated*.cpp
    // miss at the cost of a multiply, and all lookups move to slowpath.
    static int exportInsert(const char* namep) VL_MT_SAFE {
        // Slow ok - called once/function at creation
-        VerilatedLockGuard lock(s_s.m_exportMutex);
-        ExportNameMap::iterator it = s_s.m_exportMap.find(namep);
-        if (it == s_s.m_exportMap.end()) {
-            s_s.m_exportMap.insert(it, std::make_pair(namep, s_s.m_exportNext++));
-            return s_s.m_exportNext++;
+        const VerilatedLockGuard lock(s_s.v.m_exportMutex);
+        const auto it = s_s.v.m_exportMap.find(namep);
+        if (it == s_s.v.m_exportMap.end()) {
+            s_s.v.m_exportMap.insert(it, std::make_pair(namep, s_s.v.m_exportNext++));
+            return s_s.v.m_exportNext++;
        } else {
            return it->second;
        }
    }
    static int exportFind(const char* namep) VL_MT_SAFE {
-        VerilatedLockGuard lock(s_s.m_exportMutex);
-        ExportNameMap::const_iterator it = s_s.m_exportMap.find(namep);
-        if (VL_LIKELY(it != s_s.m_exportMap.end())) return it->second;
+        const VerilatedLockGuard lock(s_s.v.m_exportMutex);
+        const auto& it = s_s.v.m_exportMap.find(namep);
+        if (VL_LIKELY(it != s_s.v.m_exportMap.end())) return it->second;
        std::string msg = (std::string("%Error: Testbench C called ") + namep
                           + " but no such DPI export function name exists in ANY model");
        VL_FATAL_MT("unknown", 0, "", msg.c_str());
@@ -408,23 +445,21 @@ public:  // But only for verilated*.cpp
    }
    static const char* exportName(int funcnum) VL_MT_SAFE {
        // Slowpath; find name for given export; errors only so no map to reverse-map it
-        VerilatedLockGuard lock(s_s.m_exportMutex);
-        for (ExportNameMap::const_iterator it = s_s.m_exportMap.begin();
-             it != s_s.m_exportMap.end(); ++it) {
-            if (it->second == funcnum) return it->first;
+        const VerilatedLockGuard lock(s_s.v.m_exportMutex);
+        for (const auto& i : s_s.v.m_exportMap) {
+            if (i.second == funcnum) return i.first;
        }
        return "*UNKNOWN*";
    }
    static void exportsDump() VL_MT_SAFE {
-        VerilatedLockGuard lock(s_s.m_exportMutex);
+        const VerilatedLockGuard lock(s_s.v.m_exportMutex);
        bool first = true;
-        for (ExportNameMap::const_iterator it = s_s.m_exportMap.begin();
-             it != s_s.m_exportMap.end(); ++it) {
+        for (const auto& i : s_s.v.m_exportMap) {
            if (first) {
                VL_PRINTF_MT("  exportDump:\n");
                first = false;
            }
-            VL_PRINTF_MT("    DPI_EXPORT_NAME %05d: %s\n", it->second, it->first);
+            VL_PRINTF_MT("    DPI_EXPORT_NAME %05d: %s\n", i.second, i.first);
        }
    }
    // We don't free up m_exportMap until the end, because we can't be sure
@@ -435,49 +470,124 @@ public:  // But only for verilated*.cpp
    static std::string timeFormatSuffix() VL_MT_SAFE;
    static void timeFormatSuffix(const std::string& value) VL_MT_SAFE;
    static int timeFormatUnits() VL_MT_SAFE {
-        if (s_s.m_ser.m_timeFormatUnits == Serialized::UNITS_NONE) {
+        if (s_s.v.m_ser.m_timeFormatUnits == VerilatedImpData::Serialized::UNITS_NONE) {
            return Verilated::timeprecision();
        }
-        return s_s.m_ser.m_timeFormatUnits;
+        return s_s.v.m_ser.m_timeFormatUnits;
    }
-    static int timeFormatPrecision() VL_MT_SAFE { return s_s.m_ser.m_timeFormatPrecision; }
-    static int timeFormatWidth() VL_MT_SAFE { return s_s.m_ser.m_timeFormatWidth; }
+    static int timeFormatPrecision() VL_MT_SAFE { return s_s.v.m_ser.m_timeFormatPrecision; }
+    static int timeFormatWidth() VL_MT_SAFE { return s_s.v.m_ser.m_timeFormatWidth; }
    static void timeFormatUnits(int value) VL_MT_SAFE;
    static void timeFormatPrecision(int value) VL_MT_SAFE;
    static void timeFormatWidth(int value) VL_MT_SAFE;

 public:  // But only for verilated*.cpp
    // METHODS - file IO
-    static IData fdNew(FILE* fp) VL_MT_SAFE {
+    static IData fdNewMcd(const char* filenamep) VL_MT_SAFE {
+        const VerilatedLockGuard lock(s_s.v.m_fdMutex);
+        if (s_s.v.m_fdFreeMct.empty()) return 0;
+        IData idx = s_s.v.m_fdFreeMct.back();
+        s_s.v.m_fdFreeMct.pop_back();
+        s_s.v.m_fdps[idx] = fopen(filenamep, "w");
+        if (VL_UNLIKELY(!s_s.v.m_fdps[idx])) return 0;
+        return (1 << idx);
+    }
+    static IData fdNew(const char* filenamep, const char* modep) VL_MT_SAFE {
+        FILE* fp = fopen(filenamep, modep);
        if (VL_UNLIKELY(!fp)) return 0;
        // Bit 31 indicates it's a descriptor not a MCD
-        VerilatedLockGuard lock(s_s.m_fdMutex);
-        if (s_s.m_fdFree.empty()) {
+        const VerilatedLockGuard lock(s_s.v.m_fdMutex);
+        if (s_s.v.m_fdFree.empty()) {
            // Need to create more space in m_fdps and m_fdFree
-            size_t start = s_s.m_fdps.size();
-            s_s.m_fdps.resize(start * 2);
-            for (size_t i = start; i < start * 2; ++i) {
-                s_s.m_fdFree.push_back(static_cast<IData>(i));
+            const std::size_t start = std::max<std::size_t>(31UL + 1UL + 3UL, s_s.v.m_fdps.size());
+            const std::size_t excess = 10;
+            s_s.v.m_fdps.resize(start + excess);
+            std::fill(s_s.v.m_fdps.begin() + start, s_s.v.m_fdps.end(), (FILE*)0);
+            s_s.v.m_fdFree.resize(excess);
+            for (std::size_t i = 0, id = start; i < s_s.v.m_fdFree.size(); ++i, ++id) {
+                s_s.v.m_fdFree[i] = id;
            }
        }
-        IData idx = s_s.m_fdFree.back();
-        s_s.m_fdFree.pop_back();
-        s_s.m_fdps[idx] = fp;
+        IData idx = s_s.v.m_fdFree.back();
+        s_s.v.m_fdFree.pop_back();
+        s_s.v.m_fdps[idx] = fp;
        return (idx | (1UL << 31));  // bit 31 indicates not MCD
    }
-    static void fdDelete(IData fdi) VL_MT_SAFE {
-        IData idx = VL_MASK_I(31) & fdi;
-        VerilatedLockGuard lock(s_s.m_fdMutex);
-        if (VL_UNLIKELY(!(fdi & (VL_ULL(1) << 31)) || idx >= s_s.m_fdps.size())) return;
-        if (VL_UNLIKELY(!s_s.m_fdps[idx])) return;  // Already free
-        s_s.m_fdps[idx] = NULL;
-        s_s.m_fdFree.push_back(idx);
+    static void fdFlush(IData fdi) VL_MT_SAFE {
+        const VerilatedLockGuard lock(s_s.v.m_fdMutex);
+        const VerilatedFpList fdlist = fdToFpList(fdi);
+        for (const auto& i : fdlist) fflush(i);
+    }
+    static IData fdSeek(IData fdi, IData offset, IData origin) VL_MT_SAFE {
+        const VerilatedLockGuard lock(s_s.v.m_fdMutex);
+        const VerilatedFpList fdlist = fdToFpList(fdi);
+        if (VL_UNLIKELY(fdlist.size() != 1)) return 0;
+        return static_cast<IData>(
+            fseek(*fdlist.begin(), static_cast<long>(offset), static_cast<int>(origin)));
+    }
+    static IData fdTell(IData fdi) VL_MT_SAFE {
+        const VerilatedLockGuard lock(s_s.v.m_fdMutex);
+        const VerilatedFpList fdlist = fdToFpList(fdi);
+        if (VL_UNLIKELY(fdlist.size() != 1)) return 0;
+        return static_cast<IData>(ftell(*fdlist.begin()));
+    }
+    static void fdWrite(IData fdi, const std::string& output) VL_MT_SAFE {
+        const VerilatedLockGuard lock(s_s.v.m_fdMutex);
+        const VerilatedFpList fdlist = fdToFpList(fdi);
+        for (const auto& i : fdlist) {
+            if (VL_UNLIKELY(!i)) continue;
+            (void)fwrite(output.c_str(), 1, output.size(), i);
+        }
+    }
+    static void fdClose(IData fdi) VL_MT_SAFE {
+        const VerilatedLockGuard lock(s_s.v.m_fdMutex);
+        if ((fdi & (1 << 31)) != 0) {
+            // Non-MCD case
+            IData idx = VL_MASK_I(31) & fdi;
+            if (VL_UNLIKELY(idx >= s_s.v.m_fdps.size())) return;
+            if (VL_UNLIKELY(!s_s.v.m_fdps[idx])) return;  // Already free
+            fclose(s_s.v.m_fdps[idx]);
+            s_s.v.m_fdps[idx] = (FILE*)0;
+            s_s.v.m_fdFree.push_back(idx);
+        } else {
+            // MCD case
+            for (int i = 0; (fdi != 0) && (i < 31); i++, fdi >>= 1) {
+                if (fdi & VL_MASK_I(1)) {
+                    fclose(s_s.v.m_fdps[i]);
+                    s_s.v.m_fdps[i] = nullptr;
+                    s_s.v.m_fdFreeMct.push_back(i);
+                }
+            }
+        }
    }
    static inline FILE* fdToFp(IData fdi) VL_MT_SAFE {
-        IData idx = VL_MASK_I(31) & fdi;
-        VerilatedLockGuard lock(s_s.m_fdMutex);  // This might get slow, if it does we can cache it
-        if (VL_UNLIKELY(!(fdi & (VL_ULL(1) << 31)) || idx >= s_s.m_fdps.size())) return NULL;
-        return s_s.m_fdps[idx];
+        const VerilatedLockGuard lock(s_s.v.m_fdMutex);
+        const VerilatedFpList fdlist = fdToFpList(fdi);
+        if (VL_UNLIKELY(fdlist.size() != 1)) return nullptr;
+        return *fdlist.begin();
+    }
+
+private:
+    static inline VerilatedFpList fdToFpList(IData fdi) VL_REQUIRES(s_s.v.m_fdMutex) {
+        VerilatedFpList fp;
+        if ((fdi & (1 << 31)) != 0) {
+            // Non-MCD case
+            const IData idx = fdi & VL_MASK_I(31);
+            switch (idx) {
+            case 0: fp.push_back(stdin); break;
+            case 1: fp.push_back(stdout); break;
+            case 2: fp.push_back(stderr); break;
+            default:
+                if (VL_LIKELY(idx < s_s.v.m_fdps.size())) fp.push_back(s_s.v.m_fdps[idx]);
+                break;
+            }
+        } else {
+            // MCD Case
+            for (int i = 0; (fdi != 0) && (i < fp.capacity()); ++i, fdi >>= 1) {
+                if (fdi & VL_MASK_I(1)) fp.push_back(s_s.v.m_fdps[i]);
+            }
+        }
+        return fp;
    }
 };

@@ -123,13 +123,13 @@ void VerilatedSave::open(const char* filenamep) VL_MT_UNSAFE_ONE {
    if (isOpen()) return;
    VL_DEBUG_IF(VL_DBG_MSGF("- save: opening save file %s\n", filenamep););

-    if (filenamep[0] == '|') {
-        assert(0);  // Not supported yet.
+    if (VL_UNCOVERABLE(filenamep[0] == '|')) {
+        assert(0);  // LCOV_EXCL_LINE // Not supported yet.
    } else {
        // cppcheck-suppress duplicateExpression
        m_fd = ::open(filenamep,
                      O_CREAT | O_WRONLY | O_TRUNC | O_LARGEFILE | O_NONBLOCK | O_CLOEXEC, 0666);
-        if (m_fd < 0) {
+        if (VL_UNLIKELY(m_fd < 0)) {
            // User code can check isOpen()
            m_isOpen = false;
            return;
@@ -146,12 +146,12 @@ void VerilatedRestore::open(const char* filenamep) VL_MT_UNSAFE_ONE {
    if (isOpen()) return;
    VL_DEBUG_IF(VL_DBG_MSGF("- restore: opening restore file %s\n", filenamep););

-    if (filenamep[0] == '|') {
-        assert(0);  // Not supported yet.
+    if (VL_UNCOVERABLE(filenamep[0] == '|')) {
+        assert(0);  // LCOV_EXCL_LINE // Not supported yet.
    } else {
        // cppcheck-suppress duplicateExpression
        m_fd = ::open(filenamep, O_CREAT | O_RDONLY | O_LARGEFILE | O_CLOEXEC, 0666);
-        if (m_fd < 0) {
+        if (VL_UNLIKELY(m_fd < 0)) {
            // User code can check isOpen()
            m_isOpen = false;
            return;
@@ -194,13 +194,15 @@ void VerilatedSave::flush() VL_MT_UNSAFE_ONE {
        ssize_t got = ::write(m_fd, wp, remaining);
        if (got > 0) {
            wp += got;
-        } else if (got < 0) {
-            if (errno != EAGAIN && errno != EINTR) {
+        } else if (VL_UNCOVERABLE(got < 0)) {
+            if (VL_UNCOVERABLE(errno != EAGAIN && errno != EINTR)) {
+                // LCOV_EXCL_START
                // write failed, presume error (perhaps out of disk space)
                std::string msg = std::string(__FUNCTION__) + ": " + strerror(errno);
                VL_FATAL_MT("", 0, "", msg.c_str());
                close();
                break;
+                // LCOV_EXCL_STOP
            }
        }
    }
@@ -223,13 +225,15 @@ void VerilatedRestore::fill() VL_MT_UNSAFE_ONE {
        ssize_t got = ::read(m_fd, m_endp, remaining);
        if (got > 0) {
            m_endp += got;
-        } else if (got < 0) {
-            if (errno != EAGAIN && errno != EINTR) {
+        } else if (VL_UNCOVERABLE(got < 0)) {
+            if (VL_UNCOVERABLE(errno != EAGAIN && errno != EINTR)) {
+                // LCOV_EXCL_START
                // write failed, presume error (perhaps out of disk space)
                std::string msg = std::string(__FUNCTION__) + ": " + strerror(errno);
                VL_FATAL_MT("", 0, "", msg.c_str());
                close();
                break;
+                // LCOV_EXCL_STOP
            }
        } else {  // got==0, EOF
            // Fill buffer from here to end with NULLs so reader's don't
@@ -34,7 +34,7 @@ protected:
    // For speed, keep m_cp as the first member of this structure
    vluint8_t* m_cp;  ///< Current pointer into m_bufp buffer
    vluint8_t* m_bufp;  ///< Output buffer
-    bool m_isOpen;  ///< True indicates open file/stream
+    bool m_isOpen = false;  ///< True indicates open file/stream
    std::string m_filename;  ///< Filename, for error messages
    VerilatedAssertOneThread m_assertOne;  ///< Assert only called from single thread

@@ -49,13 +49,12 @@ protected:

 public:
    VerilatedSerialize() {
-        m_isOpen = false;
        m_bufp = new vluint8_t[bufferSize()];
        m_cp = m_bufp;
    }
    virtual ~VerilatedSerialize() {
        close();
-        if (m_bufp) VL_DO_CLEAR(delete m_bufp, m_bufp = NULL);
+        if (m_bufp) VL_DO_CLEAR(delete[] m_bufp, m_bufp = nullptr);
    }
    // METHODS
    bool isOpen() const { return m_isOpen; }
@@ -94,8 +93,8 @@ protected:
    // For speed, keep m_cp as the first member of this structure
    vluint8_t* m_cp;  ///< Current pointer into m_bufp buffer
    vluint8_t* m_bufp;  ///< Output buffer
-    vluint8_t* m_endp;  ///< Last valid byte in m_bufp buffer
-    bool m_isOpen;  ///< True indicates open file/stream
+    vluint8_t* m_endp = nullptr;  ///< Last valid byte in m_bufp buffer
+    bool m_isOpen = false;  ///< True indicates open file/stream
    std::string m_filename;  ///< Filename, for error messages
    VerilatedAssertOneThread m_assertOne;  ///< Assert only called from single thread

@@ -111,14 +110,12 @@ protected:

 public:
    VerilatedDeserialize() {
-        m_isOpen = false;
        m_bufp = new vluint8_t[bufferSize()];
        m_cp = m_bufp;
-        m_endp = NULL;
    }
    virtual ~VerilatedDeserialize() {
        close();
-        if (m_bufp) VL_DO_CLEAR(delete m_bufp, m_bufp = NULL);
+        if (m_bufp) VL_DO_CLEAR(delete[] m_bufp, m_bufp = nullptr);
    }
    // METHODS
    bool isOpen() const { return m_isOpen; }
@@ -159,19 +156,18 @@ private:

 class VerilatedSave : public VerilatedSerialize {
 private:
-    int m_fd;  ///< File descriptor we're writing to
+    int m_fd = -1;  ///< File descriptor we're writing to

 public:
    // CONSTRUCTORS
-    VerilatedSave()
-        : m_fd(-1) {}
-    virtual ~VerilatedSave() VL_OVERRIDE { close(); }
+    VerilatedSave() {}
+    virtual ~VerilatedSave() override { close(); }
    // METHODS
    /// Open the file; call isOpen() to see if errors
    void open(const char* filenamep) VL_MT_UNSAFE_ONE;
    void open(const std::string& filename) VL_MT_UNSAFE_ONE { open(filename.c_str()); }
-    virtual void close() VL_OVERRIDE VL_MT_UNSAFE_ONE;
-    virtual void flush() VL_OVERRIDE VL_MT_UNSAFE_ONE;
+    virtual void close() override VL_MT_UNSAFE_ONE;
+    virtual void flush() override VL_MT_UNSAFE_ONE;
 };

 //=============================================================================
@@ -180,21 +176,20 @@ public:

 class VerilatedRestore : public VerilatedDeserialize {
 private:
-    int m_fd;  ///< File descriptor we're writing to
+    int m_fd = -1;  ///< File descriptor we're writing to

 public:
    // CONSTRUCTORS
-    VerilatedRestore()
-        : m_fd(-1) {}
-    virtual ~VerilatedRestore() VL_OVERRIDE { close(); }
+    VerilatedRestore() {}
+    virtual ~VerilatedRestore() override { close(); }

    // METHODS
    /// Open the file; call isOpen() to see if errors
    void open(const char* filenamep) VL_MT_UNSAFE_ONE;
    void open(const std::string& filename) VL_MT_UNSAFE_ONE { open(filename.c_str()); }
-    virtual void close() VL_OVERRIDE VL_MT_UNSAFE_ONE;
-    virtual void flush() VL_OVERRIDE VL_MT_UNSAFE_ONE {}
-    virtual void fill() VL_OVERRIDE VL_MT_UNSAFE_ONE;
+    virtual void close() override VL_MT_UNSAFE_ONE;
+    virtual void flush() override VL_MT_UNSAFE_ONE {}
+    virtual void fill() override VL_MT_UNSAFE_ONE;
 };

 //=============================================================================
@@ -257,10 +252,9 @@ VerilatedSerialize& operator<<(VerilatedSerialize& os, VlAssocArray<T_Key, T_Val
    os << rhs.atDefault();
    vluint32_t len = rhs.size();
    os << len;
-    for (typename VlAssocArray<T_Key, T_Value>::const_iterator it = rhs.begin(); it != rhs.end();
-         ++it) {
-        T_Key index = it->first;  // Copy to get around const_iterator
-        T_Value value = it->second;
+    for (const auto& i : rhs) {
+        T_Key index = i.first;  // Copy to get around const_iterator
+        T_Value value = i.second;
        os << index << value;
    }
    return os;
@@ -29,6 +29,8 @@

 #include "verilatedos.h"

+#include <vector>
+
 //===========================================================================
 /// Verilator range
 /// Thread safety: Assume is constructed only with model, then any number of readers
@@ -42,11 +44,11 @@ protected:
    friend class VerilatedVarProps;
    friend class VerilatedScope;
    VerilatedRange()
-        : m_left(0)
-        , m_right(0) {}
+        : m_left{0}
+        , m_right{0} {}
    VerilatedRange(int left, int right)
-        : m_left(left)
-        , m_right(right) {}
+        : m_left{left}
+        , m_right{right} {}
    void init(int left, int right) {
        m_left = left;
        m_right = right;
@@ -78,96 +80,61 @@ class VerilatedVarProps {
    const int m_pdims;  // Packed dimensions
    const int m_udims;  // Unpacked dimensions
    VerilatedRange m_packed;  // Packed array range
-    VerilatedRange m_unpacked[3];  // Unpacked array range
+    std::vector<VerilatedRange> m_unpacked;  // Unpacked array ranges
+    void initUnpacked(const int* ulims) {
+        for (int i = 0; i < m_udims; ++i) {
+            const int left = ulims ? ulims[2 * i + 0] : 0;
+            const int right = ulims ? ulims[2 * i + 1] : 0;
+            m_unpacked.push_back(VerilatedRange(left, right));
+        }
+    }
    // CONSTRUCTORS
 protected:
    friend class VerilatedScope;
    VerilatedVarProps(VerilatedVarType vltype, VerilatedVarFlags vlflags, int pdims, int udims)
-        : m_magic(MAGIC)
-        , m_vltype(vltype)
-        , m_vlflags(vlflags)
-        , m_pdims(pdims)
-        , m_udims(udims) {}
+        : m_magic{MAGIC}
+        , m_vltype{vltype}
+        , m_vlflags{vlflags}
+        , m_pdims{pdims}
+        , m_udims{udims} {
+        initUnpacked(nullptr);
+    }

 public:
    class Unpacked {};
    // Without packed
    VerilatedVarProps(VerilatedVarType vltype, int vlflags)
-        : m_magic(MAGIC)
-        , m_vltype(vltype)
-        , m_vlflags(VerilatedVarFlags(vlflags))
-        , m_pdims(0)
-        , m_udims(0) {}
-    VerilatedVarProps(VerilatedVarType vltype, int vlflags, Unpacked, int u0l, int u0r)
-        : m_magic(MAGIC)
-        , m_vltype(vltype)
-        , m_vlflags(VerilatedVarFlags(vlflags))
-        , m_pdims(0)
-        , m_udims(1) {
-        m_unpacked[0].init(u0l, u0r);
-    }
-    VerilatedVarProps(VerilatedVarType vltype, int vlflags, Unpacked, int u0l, int u0r, int u1l,
-                      int u1r)
-        : m_magic(MAGIC)
-        , m_vltype(vltype)
-        , m_vlflags(VerilatedVarFlags(vlflags))
-        , m_pdims(0)
-        , m_udims(2) {
-        m_unpacked[0].init(u0l, u0r);
-        m_unpacked[1].init(u1l, u1r);
-    }
-    VerilatedVarProps(VerilatedVarType vltype, int vlflags, Unpacked, int u0l, int u0r, int u1l,
-                      int u1r, int u2l, int u2r)
-        : m_magic(MAGIC)
-        , m_vltype(vltype)
-        , m_vlflags(VerilatedVarFlags(vlflags))
-        , m_pdims(0)
-        , m_udims(3) {
-        m_unpacked[0].init(u0l, u0r);
-        m_unpacked[1].init(u1l, u1r);
-        m_unpacked[2].init(u2l, u2r);
+        : m_magic{MAGIC}
+        , m_vltype{vltype}
+        , m_vlflags(VerilatedVarFlags(vlflags))  // Need () or GCC 4.8 false warning
+        , m_pdims{0}
+        , m_udims{0} {}
+    VerilatedVarProps(VerilatedVarType vltype, int vlflags, Unpacked, int udims, const int* ulims)
+        : m_magic{MAGIC}
+        , m_vltype{vltype}
+        , m_vlflags(VerilatedVarFlags(vlflags))  // Need () or GCC 4.8 false warning
+        , m_pdims{0}
+        , m_udims{udims} {
+        initUnpacked(ulims);
    }
    // With packed
    class Packed {};
    VerilatedVarProps(VerilatedVarType vltype, int vlflags, Packed, int pl, int pr)
-        : m_magic(MAGIC)
-        , m_vltype(vltype)
-        , m_vlflags(VerilatedVarFlags(vlflags))
-        , m_pdims(1)
-        , m_udims(0)
-        , m_packed(pl, pr) {}
+        : m_magic{MAGIC}
+        , m_vltype{vltype}
+        , m_vlflags(VerilatedVarFlags(vlflags))  // Need () or GCC 4.8 false warning
+        , m_pdims{1}
+        , m_udims{0}
+        , m_packed{pl, pr} {}
    VerilatedVarProps(VerilatedVarType vltype, int vlflags, Packed, int pl, int pr, Unpacked,
-                      int u0l, int u0r)
-        : m_magic(MAGIC)
-        , m_vltype(vltype)
-        , m_vlflags(VerilatedVarFlags(vlflags))
-        , m_pdims(1)
-        , m_udims(1)
-        , m_packed(pl, pr) {
-        m_unpacked[0].init(u0l, u0r);
-    }
-    VerilatedVarProps(VerilatedVarType vltype, int vlflags, Packed, int pl, int pr, Unpacked,
-                      int u0l, int u0r, int u1l, int u1r)
-        : m_magic(MAGIC)
-        , m_vltype(vltype)
-        , m_vlflags(VerilatedVarFlags(vlflags))
-        , m_pdims(1)
-        , m_udims(2)
-        , m_packed(pl, pr) {
-        m_unpacked[0].init(u0l, u0r);
-        m_unpacked[1].init(u1l, u1r);
-    }
-    VerilatedVarProps(VerilatedVarType vltype, int vlflags, Packed, int pl, int pr, Unpacked,
-                      int u0l, int u0r, int u1l, int u1r, int u2l, int u2r)
-        : m_magic(MAGIC)
-        , m_vltype(vltype)
-        , m_vlflags(VerilatedVarFlags(vlflags))
-        , m_pdims(1)
-        , m_udims(3)
-        , m_packed(pl, pr) {
-        m_unpacked[0].init(u0l, u0r);
-        m_unpacked[1].init(u1l, u1r);
-        m_unpacked[2].init(u2l, u2r);
+                      int udims, const int* ulims)
+        : m_magic{MAGIC}
+        , m_vltype{vltype}
+        , m_vlflags(VerilatedVarFlags(vlflags))  // Need () or GCC 4.8 false warning
+        , m_pdims{1}
+        , m_udims{udims}
+        , m_packed{pl, pr} {
+        initUnpacked(ulims);
    }

 public:
@@ -189,27 +156,29 @@ public:
    // DPI accessors
    int left(int dim) const {
        return dim == 0 ? m_packed.left()
-                        : VL_LIKELY(dim >= 1 && dim <= 3) ? m_unpacked[dim - 1].left() : 0;
+                        : VL_LIKELY(dim >= 1 && dim <= udims()) ? m_unpacked[dim - 1].left() : 0;
    }
    int right(int dim) const {
        return dim == 0 ? m_packed.right()
-                        : VL_LIKELY(dim >= 1 && dim <= 3) ? m_unpacked[dim - 1].right() : 0;
+                        : VL_LIKELY(dim >= 1 && dim <= udims()) ? m_unpacked[dim - 1].right() : 0;
    }
    int low(int dim) const {
        return dim == 0 ? m_packed.low()
-                        : VL_LIKELY(dim >= 1 && dim <= 3) ? m_unpacked[dim - 1].low() : 0;
+                        : VL_LIKELY(dim >= 1 && dim <= udims()) ? m_unpacked[dim - 1].low() : 0;
    }
    int high(int dim) const {
        return dim == 0 ? m_packed.high()
-                        : VL_LIKELY(dim >= 1 && dim <= 3) ? m_unpacked[dim - 1].high() : 0;
+                        : VL_LIKELY(dim >= 1 && dim <= udims()) ? m_unpacked[dim - 1].high() : 0;
    }
    int increment(int dim) const {
-        return dim == 0 ? m_packed.increment()
-                        : VL_LIKELY(dim >= 1 && dim <= 3) ? m_unpacked[dim - 1].increment() : 0;
+        return dim == 0
+                   ? m_packed.increment()
+                   : VL_LIKELY(dim >= 1 && dim <= udims()) ? m_unpacked[dim - 1].increment() : 0;
    }
    int elements(int dim) const {
-        return dim == 0 ? m_packed.elements()
-                        : VL_LIKELY(dim >= 1 && dim <= 3) ? m_unpacked[dim - 1].elements() : 0;
+        return dim == 0
+                   ? m_packed.elements()
+                   : VL_LIKELY(dim >= 1 && dim <= udims()) ? m_unpacked[dim - 1].elements() : 0;
    }
    /// Total size in bytes (note DPI limited to 4GB)
    size_t totalSize() const;
@@ -227,11 +196,11 @@ class VerilatedDpiOpenVar {
 public:
    // CONSTRUCTORS
    VerilatedDpiOpenVar(const VerilatedVarProps* propsp, void* datap)
-        : m_propsp(propsp)
-        , m_datap(datap) {}
+        : m_propsp{propsp}
+        , m_datap{datap} {}
    VerilatedDpiOpenVar(const VerilatedVarProps* propsp, const void* datap)
-        : m_propsp(propsp)
-        , m_datap(const_cast<void*>(datap)) {}
+        : m_propsp{propsp}
+        , m_datap{const_cast<void*>(datap)} {}
    ~VerilatedDpiOpenVar() {}
    // METHODS
    void* datap() const { return m_datap; }
@@ -263,13 +232,15 @@ class VerilatedVar : public VerilatedVarProps {
    void* m_datap;  // Location of data
    const char* m_namep;  // Name - slowpath
 protected:
+    bool m_isParam;
    friend class VerilatedScope;
    // CONSTRUCTORS
    VerilatedVar(const char* namep, void* datap, VerilatedVarType vltype,
-                 VerilatedVarFlags vlflags, int dims)
-        : VerilatedVarProps(vltype, vlflags, (dims > 0 ? 1 : 0), ((dims > 1) ? dims - 1 : 0))
-        , m_datap(datap)
-        , m_namep(namep) {}
+                 VerilatedVarFlags vlflags, int dims, bool isParam)
+        : VerilatedVarProps{vltype, vlflags, (dims > 0 ? 1 : 0), ((dims > 1) ? dims - 1 : 0)}
+        , m_datap{datap}
+        , m_namep{namep}
+        , m_isParam{isParam} {}

 public:
    ~VerilatedVar() {}
@@ -278,6 +249,7 @@ public:
    const VerilatedRange& range() const { return packed(); }  // Deprecated
    const VerilatedRange& array() const { return unpacked(); }  // Deprecated
    const char* name() const { return m_namep; }
+    bool isParam() const { return m_isParam; }
 };

 #endif  // Guard
@@ -21,14 +21,14 @@

 std::atomic<vluint64_t> VlMTaskVertex::s_yields;

-VL_THREAD_LOCAL VlThreadPool::ProfileTrace* VlThreadPool::t_profilep = NULL;
+VL_THREAD_LOCAL VlThreadPool::ProfileTrace* VlThreadPool::t_profilep = nullptr;

 //=============================================================================
 // VlMTaskVertex

 VlMTaskVertex::VlMTaskVertex(vluint32_t upstreamDepCount)
-    : m_upstreamDepsDone(0)
-    , m_upstreamDepCount(upstreamDepCount) {
+    : m_upstreamDepsDone{0}
+    , m_upstreamDepCount{upstreamDepCount} {
    assert(atomic_is_lock_free(&m_upstreamDepsDone));
 }

@@ -36,13 +36,11 @@ VlMTaskVertex::VlMTaskVertex(vluint32_t upstreamDepCount)
 // VlWorkerThread

 VlWorkerThread::VlWorkerThread(VlThreadPool* poolp, bool profiling)
-    : m_waiting(false)
-    , m_ready_size(0)
-    , m_poolp(poolp)
-    , m_profiling(profiling)
-    , m_exiting(false)
-    // Must init this last -- after setting up fields that it might read:
-    , m_cthread(startWorker, this) {}
+    : m_waiting{false}
+    , m_poolp{poolp}
+    , m_profiling{profiling}  // Must init this last -- after setting up fields that it might read:
+    , m_exiting{false}
+    , m_cthread{startWorker, this} {}

 VlWorkerThread::~VlWorkerThread() {
    m_exiting.store(true, std::memory_order_release);
@@ -55,7 +53,7 @@ void VlWorkerThread::workerLoop() {
    if (VL_UNLIKELY(m_profiling)) m_poolp->setupProfilingClientThread();

    ExecRec work;
-    work.m_fnp = NULL;
+    work.m_fnp = nullptr;

    while (true) {
        if (VL_LIKELY(!work.m_fnp)) dequeWork(&work);
@@ -65,7 +63,7 @@ void VlWorkerThread::workerLoop() {

        if (VL_LIKELY(work.m_fnp)) {
            work.m_fnp(work.m_evenCycle, work.m_sym);
-            work.m_fnp = NULL;
+            work.m_fnp = nullptr;
        }
    }

@@ -78,7 +76,7 @@ void VlWorkerThread::startWorker(VlWorkerThread* workerp) { workerp->workerLoop(
 // VlThreadPool

 VlThreadPool::VlThreadPool(int nThreads, bool profiling)
-    : m_profiling(profiling) {
+    : m_profiling{profiling} {
    // --threads N passes nThreads=N-1, as the "main" threads counts as 1
    unsigned cpus = std::thread::hardware_concurrency();
    if (cpus < nThreads + 1) {
@@ -110,7 +108,7 @@ VlThreadPool::~VlThreadPool() {
 void VlThreadPool::tearDownProfilingClientThread() {
    assert(t_profilep);
    delete t_profilep;
-    t_profilep = NULL;
+    t_profilep = nullptr;
 }

 void VlThreadPool::setupProfilingClientThread() {
@@ -120,21 +118,21 @@ void VlThreadPool::setupProfilingClientThread() {
    // try not to malloc while collecting profiling.
    t_profilep->reserve(4096);
    {
-        VerilatedLockGuard lk(m_mutex);
+        const VerilatedLockGuard lk(m_mutex);
        m_allProfiles.insert(t_profilep);
    }
 }

 void VlThreadPool::profileAppendAll(const VlProfileRec& rec) {
-    VerilatedLockGuard lk(m_mutex);
-    for (ProfileSet::iterator it = m_allProfiles.begin(); it != m_allProfiles.end(); ++it) {
+    const VerilatedLockGuard lk(m_mutex);
+    for (const auto& profilep : m_allProfiles) {
        // Every thread's profile trace gets a copy of rec.
-        (*it)->emplace_back(rec);
+        profilep->emplace_back(rec);
    }
 }

 void VlThreadPool::profileDump(const char* filenamep, vluint64_t ticksElapsed) {
-    VerilatedLockGuard lk(m_mutex);
+    const VerilatedLockGuard lk(m_mutex);
    VL_DEBUG_IF(VL_DBG_MSGF("+prof+threads writing to '%s'\n", filenamep););

    FILE* fp = fopen(filenamep, "w");
@@ -154,13 +152,12 @@ void VlThreadPool::profileDump(const char* filenamep, vluint64_t ticksElapsed) {
    fprintf(fp, "VLPROF stat yields %" VL_PRI64 "u\n", VlMTaskVertex::yields());

    vluint32_t thread_id = 0;
-    for (ProfileSet::const_iterator pit = m_allProfiles.begin(); pit != m_allProfiles.end();
-         ++pit) {
+    for (const auto& pi : m_allProfiles) {
        ++thread_id;

        bool printing = false;  // False while in warmup phase
-        for (ProfileTrace::const_iterator eit = (*pit)->begin(); eit != (*pit)->end(); ++eit) {
-            switch (eit->m_type) {
+        for (const auto& ei : *pi) {
+            switch (ei.m_type) {
            case VlProfileRec::TYPE_BARRIER:  //
                printing = true;
                break;
@@ -170,9 +167,8 @@ void VlThreadPool::profileDump(const char* filenamep, vluint64_t ticksElapsed) {
                        "VLPROF mtask %d"
                        " start %" VL_PRI64 "u end %" VL_PRI64 "u elapsed %" VL_PRI64 "u"
                        " predict_time %u cpu %u on thread %u\n",
-                        eit->m_mtaskId, eit->m_startTime, eit->m_endTime,
-                        (eit->m_endTime - eit->m_startTime), eit->m_predictTime, eit->m_cpu,
-                        thread_id);
+                        ei.m_mtaskId, ei.m_startTime, ei.m_endTime,
+                        (ei.m_endTime - ei.m_startTime), ei.m_predictTime, ei.m_cpu, thread_id);
                break;
            default: assert(false); break;  // LCOV_EXCL_LINE
            }
@@ -119,23 +119,16 @@ class VlProfileRec {
 protected:
    friend class VlThreadPool;
    enum VlProfileE { TYPE_MTASK_RUN, TYPE_BARRIER };
-    VlProfileE m_type;  // Record type
-    vluint32_t m_mtaskId;  // Mtask we're logging
-    vluint32_t m_predictTime;  // How long scheduler predicted would take
-    vluint64_t m_startTime;  // Tick at start of execution
-    vluint64_t m_endTime;  // Tick at end of execution
+    VlProfileE m_type = TYPE_BARRIER;  // Record type
+    vluint32_t m_mtaskId = 0;  // Mtask we're logging
+    vluint32_t m_predictTime = 0;  // How long scheduler predicted would take
+    vluint64_t m_startTime = 0;  // Tick at start of execution
+    vluint64_t m_endTime = 0;  // Tick at end of execution
    unsigned m_cpu;  // Execution CPU number (at start anyways)
 public:
    class Barrier {};
    VlProfileRec() {}
-    explicit VlProfileRec(Barrier) {
-        m_type = TYPE_BARRIER;
-        m_mtaskId = 0;
-        m_predictTime = 0;
-        m_startTime = 0;
-        m_endTime = 0;
-        m_cpu = getcpu();
-    }
+    explicit VlProfileRec(Barrier) { m_cpu = getcpu(); }
    void startRecord(vluint64_t time, uint32_t mtask, uint32_t predict) {
        m_type = VlProfileRec::TYPE_MTASK_RUN;
        m_mtaskId = mtask;
@@ -174,13 +167,13 @@ private:
        VlThrSymTab m_sym;  // Symbol table to execute
        bool m_evenCycle;  // Even/odd for flag alternation
        ExecRec()
-            : m_fnp(NULL)
-            , m_sym(NULL)
-            , m_evenCycle(false) {}
+            : m_fnp{nullptr}
+            , m_sym{nullptr}
+            , m_evenCycle{false} {}
        ExecRec(VlExecFnp fnp, bool evenCycle, VlThrSymTab sym)
-            : m_fnp(fnp)
-            , m_sym(sym)
-            , m_evenCycle(evenCycle) {}
+            : m_fnp{fnp}
+            , m_sym{sym}
+            , m_evenCycle{evenCycle} {}
    };

    // MEMBERS
@@ -234,7 +227,7 @@ public:
    inline void addTask(VlExecFnp fnp, bool evenCycle, VlThrSymTab sym) {
        bool notify;
        {
-            VerilatedLockGuard lk(m_mutex);
+            const VerilatedLockGuard lk(m_mutex);
            m_ready.emplace_back(fnp, evenCycle, sym);
            m_ready_size.fetch_add(1, std::memory_order_relaxed);
            notify = m_waiting;
@@ -40,7 +40,7 @@
 // Threaded tracing

 // A simple synchronized first in first out queue
-template <class T> class VerilatedThreadQueue {
+template <class T> class VerilatedThreadQueue {  // LCOV_EXCL_LINE  // lcov bug
 private:
    VerilatedMutex m_mutex;  // Protects m_queue
    std::condition_variable_any m_cv;
@@ -73,7 +73,7 @@ public:

    // Non blocking get
    bool tryGet(T& result) {
-        VerilatedLockGuard lockGuard(m_mutex);
+        const VerilatedLockGuard lockGuard(m_mutex);
        if (m_queue.empty()) { return false; }
        result = m_queue.front();
        m_queue.pop_front();
@@ -87,7 +87,7 @@ class VerilatedTraceCommand {
 public:
    // These must all fit in 4 bit at the moment, as the tracing routines
    // pack parameters in the top bits.
-    enum {
+    enum : vluint8_t {
        CHG_BIT_0 = 0x0,
        CHG_BIT_1 = 0x1,
        CHG_CDATA = 0x2,
@@ -95,7 +95,6 @@ public:
        CHG_IDATA = 0x4,
        CHG_QDATA = 0x5,
        CHG_WDATA = 0x6,
-        CHG_FLOAT = 0x7,
        CHG_DOUBLE = 0x8,
        // TODO: full..
        TIME_CHANGE = 0xd,
@@ -105,8 +104,6 @@ public:
 };
 #endif

-class VerilatedTraceCallInfo;
-
 //=============================================================================
 // VerilatedTrace

@@ -114,13 +111,38 @@ class VerilatedTraceCallInfo;
 // implementations in the format specific derived class, which must be passed
 // as the type parameter T_Derived
 template <class T_Derived> class VerilatedTrace {
-private:
+public:
    //=========================================================================
    // Generic tracing internals

+    typedef void (*initCb_t)(void*, T_Derived*, uint32_t);  // Type of init callbacks
+    typedef void (*dumpCb_t)(void*, T_Derived*);  // Type of all but init callbacks
+
+private:
+    struct CallbackRecord {
+        // Note: would make these fields const, but some old STL implementations
+        // (the one in Ubuntu 14.04 with GCC 4.8.4 in particular) use the
+        // assignment operator on inserting into collections, so they don't work
+        // with const fields...
+        union {
+            initCb_t m_initCb;  // The callback function
+            dumpCb_t m_dumpCb;  // The callback function
+        };
+        void* m_userp;  // The user pointer to pass to the callback (the symbol table)
+        CallbackRecord(initCb_t cb, void* userp)
+            : m_initCb{cb}
+            , m_userp{userp} {}
+        CallbackRecord(dumpCb_t cb, void* userp)
+            : m_dumpCb{cb}
+            , m_userp{userp} {}
+    };
+
    vluint32_t* m_sigs_oldvalp;  ///< Old value store
    vluint64_t m_timeLastDump;  ///< Last time we did a dump
-    std::vector<VerilatedTraceCallInfo*> m_callbacks;  ///< Routines to perform dumping
+    std::vector<CallbackRecord> m_initCbs;  ///< Routines to initialize traciong
+    std::vector<CallbackRecord> m_fullCbs;  ///< Routines to perform full dump
+    std::vector<CallbackRecord> m_chgCbs;  ///< Routines to perform incremental dump
+    std::vector<CallbackRecord> m_cleanupCbs;  ///< Routines to call at the end of dump
    bool m_fullDump;  ///< Whether a full dump is required on the next call to 'dump'
    vluint32_t m_nextCode;  ///< Next code number to assign
    vluint32_t m_numSignals;  ///< Number of distinct signals
@@ -130,10 +152,17 @@ private:
    double m_timeRes;  ///< Time resolution (ns/ms etc)
    double m_timeUnit;  ///< Time units (ns/ms etc)

+    void addCallbackRecord(std::vector<CallbackRecord>& cbVec, CallbackRecord& cbRec);
+
    // Equivalent to 'this' but is of the sub-type 'T_Derived*'. Use 'self()->'
    // to access duck-typed functions to avoid a virtual function call.
    T_Derived* self() { return static_cast<T_Derived*>(this); }

+    // Flush any remaining data for this file
+    static void onFlush(void* selfp) VL_MT_UNSAFE_ONE;
+    // Close the file on termination
+    static void onExit(void* selfp) VL_MT_UNSAFE_ONE;
+
 #ifdef VL_TRACE_THREADED
    // Number of total trace buffers that have been allocated
    vluint32_t m_numTraceBuffers;
@@ -209,8 +238,8 @@ protected:

    // These hooks are called before a full or change based dump is produced.
    // The return value indicates whether to proceed with the dump.
-    virtual bool preFullDump() { return true; }
-    virtual bool preChangeDump() { return true; }
+    virtual bool preFullDump() = 0;
+    virtual bool preChangeDump() = 0;

 public:
    //=========================================================================
@@ -232,13 +261,13 @@ public:
    //=========================================================================
    // Non-hot path internal interface to Verilator generated code

-    typedef void (*callback_t)(T_Derived* tracep, void* userthis, vluint32_t code);
+    void addInitCb(initCb_t cb, void* userp) VL_MT_UNSAFE_ONE;
+    void addFullCb(dumpCb_t cb, void* userp) VL_MT_UNSAFE_ONE;
+    void addChgCb(dumpCb_t cb, void* userp) VL_MT_UNSAFE_ONE;
+    void addCleanupCb(dumpCb_t cb, void* userp) VL_MT_UNSAFE_ONE;

    void changeThread() { m_assertOne.changeThread(); }

-    void addCallback(callback_t initcb, callback_t fullcb, callback_t changecb,
-                     void* userthis) VL_MT_UNSAFE_ONE;
-
    void module(const std::string& name) VL_MT_UNSAFE_ONE {
        m_assertOne.check();
        m_moduleName = name;
@@ -261,7 +290,6 @@ public:
    // duck-typed void emitIData(vluint32_t code, IData newval, int bits) = 0;
    // duck-typed void emitQData(vluint32_t code, QData newval, int bits) = 0;
    // duck-typed void emitWData(vluint32_t code, const WData* newvalp, int bits) = 0;
-    // duck-typed void emitFloat(vluint32_t code, float newval) = 0;
    // duck-typed void emitDouble(vluint32_t code, double newval) = 0;

    vluint32_t* oldp(vluint32_t code) { return m_sigs_oldvalp + code; }
@@ -273,7 +301,6 @@ public:
    void fullIData(vluint32_t* oldp, IData newval, int bits);
    void fullQData(vluint32_t* oldp, QData newval, int bits);
    void fullWData(vluint32_t* oldp, const WData* newvalp, int bits);
-    void fullFloat(vluint32_t* oldp, float newval);
    void fullDouble(vluint32_t* oldp, double newval);

 #ifdef VL_TRACE_THREADED
@@ -319,14 +346,6 @@ public:
        for (int i = 0; i < (bits + 31) / 32; ++i) { *m_traceBufferWritep++ = newvalp[i]; }
        VL_DEBUG_IF(assert(m_traceBufferWritep <= m_traceBufferEndp););
    }
-    inline void chgFloat(vluint32_t code, float newval) {
-        m_traceBufferWritep[0] = VerilatedTraceCommand::CHG_FLOAT;
-        m_traceBufferWritep[1] = code;
-        // cppcheck-suppress invalidPointerCast
-        *reinterpret_cast<float*>(m_traceBufferWritep + 2) = newval;
-        m_traceBufferWritep += 3;
-        VL_DEBUG_IF(assert(m_traceBufferWritep <= m_traceBufferEndp););
-    }
    inline void chgDouble(vluint32_t code, double newval) {
        m_traceBufferWritep[0] = VerilatedTraceCommand::CHG_DOUBLE;
        m_traceBufferWritep[1] = code;
@@ -374,10 +393,6 @@ public:
            }
        }
    }
-    inline void CHG(Float)(vluint32_t* oldp, float newval) {
-        // cppcheck-suppress invalidPointerCast
-        if (VL_UNLIKELY(*reinterpret_cast<float*>(oldp) != newval)) fullFloat(oldp, newval);
-    }
    inline void CHG(Double)(vluint32_t* oldp, double newval) {
        // cppcheck-suppress invalidPointerCast
        if (VL_UNLIKELY(*reinterpret_cast<double*>(oldp) != newval)) fullDouble(oldp, newval);
@@ -39,7 +39,7 @@
 // Static utility functions

 static double timescaleToDouble(const char* unitp) {
-    char* endp;
+    char* endp = nullptr;
    double value = strtod(unitp, &endp);
    // On error so we allow just "ns" to return 1e-9.
    if (value == 0.0 && endp == unitp) value = 1;
@@ -73,31 +73,6 @@ static std::string doubleToTimescale(double value) {
    return valuestr;  // Gets converted to string, so no ref to stack
 }

-//=============================================================================
-// Internal callback routines for each module being traced.
-
-// Each module that wishes to be traced registers a set of callbacks stored in
-// this class.  When the trace file is being constructed, this class provides
-// the callback routines to be executed.
-class VerilatedTraceCallInfo {
-public:  // This is in .cpp file so is not widely visible
-    typedef VerilatedTrace<VL_DERIVED_T>::callback_t callback_t;
-
-    callback_t m_initcb;  ///< Initialization Callback function
-    callback_t m_fullcb;  ///< Full Dumping Callback function
-    callback_t m_changecb;  ///< Incremental Dumping Callback function
-    void* m_userthis;  ///< User data pointer for callback
-    vluint32_t m_code;  ///< Starting code number (set later by traceInit)
-    // CONSTRUCTORS
-    VerilatedTraceCallInfo(callback_t icb, callback_t fcb, callback_t changecb, void* ut)
-        : m_initcb(icb)
-        , m_fullcb(fcb)
-        , m_changecb(changecb)
-        , m_userthis(ut)
-        , m_code(1) {}
-    ~VerilatedTraceCallInfo() {}
-};
-
 #ifdef VL_TRACE_THREADED
 //=========================================================================
 // Buffer management
@@ -196,11 +171,6 @@ template <> void VerilatedTrace<VL_DERIVED_T>::workerThreadMain() {
                chgWDataImpl(oldp, readp, top);
                readp += VL_WORDS_I(top);
                continue;
-            case VerilatedTraceCommand::CHG_FLOAT:
-                VL_TRACE_THREAD_DEBUG("Command CHG_FLOAT " << top);
-                chgFloatImpl(oldp, *reinterpret_cast<const float*>(readp));
-                readp += 1;
-                continue;
            case VerilatedTraceCommand::CHG_DOUBLE:
                VL_TRACE_THREAD_DEBUG("Command CHG_DOUBLE " << top);
                chgDoubleImpl(oldp, *reinterpret_cast<const double*>(readp));
@@ -224,13 +194,14 @@ template <> void VerilatedTrace<VL_DERIVED_T>::workerThreadMain() {
                shutdown = true;
                break;

-                //===
-                // Unknown command
-            default:
+            //===
+            // Unknown command
+            default: {  // LCOV_EXCL_START
                VL_TRACE_THREAD_DEBUG("Command UNKNOWN");
                VL_PRINTF_MT("Trace command: 0x%08x\n", cmd);
                VL_FATAL_MT(__FILE__, __LINE__, "", "Unknown trace command");
                break;
+            }  // LCOV_EXCL_STOP
            }

            // The above switch will execute 'continue' when necessary,
@@ -287,22 +258,37 @@ template <> void VerilatedTrace<VL_DERIVED_T>::flush() {
 #endif
 }

+//=============================================================================
+// Callbacks to run on global events
+
+template <> void VerilatedTrace<VL_DERIVED_T>::onFlush(void* selfp) {
+    // Note this calls 'flush' on the derived class
+    reinterpret_cast<VL_DERIVED_T*>(selfp)->flush();
+}
+
+template <> void VerilatedTrace<VL_DERIVED_T>::onExit(void* selfp) {
+    // Note this calls 'close' on the derived class
+    reinterpret_cast<VL_DERIVED_T*>(selfp)->close();
+}
+
 //=============================================================================
 // VerilatedTrace

 template <>
 VerilatedTrace<VL_DERIVED_T>::VerilatedTrace()
-    : m_sigs_oldvalp(NULL)
-    , m_timeLastDump(0)
-    , m_fullDump(true)
-    , m_nextCode(0)
-    , m_numSignals(0)
-    , m_maxBits(0)
-    , m_scopeEscape('.')
-    , m_timeRes(1e-9)
-    , m_timeUnit(1e-9)
+    : m_sigs_oldvalp{nullptr}
+    , m_timeLastDump{0}
+    , m_fullDump{true}
+    , m_nextCode{0}
+    , m_numSignals{0}
+    , m_maxBits{0}
+    , m_scopeEscape{'.'}
+    , m_timeRes{1e-9}
+    , m_timeUnit {
+    1e-9
+}
 #ifdef VL_TRACE_THREADED
-    , m_numTraceBuffers(0)
+, m_numTraceBuffers { 0 }
 #endif
 {
    set_time_unit(Verilated::timeunitString());
@@ -310,11 +296,9 @@ VerilatedTrace<VL_DERIVED_T>::VerilatedTrace()
 }

 template <> VerilatedTrace<VL_DERIVED_T>::~VerilatedTrace() {
-    if (m_sigs_oldvalp) VL_DO_CLEAR(delete[] m_sigs_oldvalp, m_sigs_oldvalp = NULL);
-    while (!m_callbacks.empty()) {
-        delete m_callbacks.back();
-        m_callbacks.pop_back();
-    }
+    if (m_sigs_oldvalp) VL_DO_CLEAR(delete[] m_sigs_oldvalp, m_sigs_oldvalp = nullptr);
+    Verilated::removeFlushCb(VerilatedTrace<VL_DERIVED_T>::onFlush, this);
+    Verilated::removeExitCb(VerilatedTrace<VL_DERIVED_T>::onExit, this);
 #ifdef VL_TRACE_THREADED
    close();
 #endif
@@ -334,11 +318,12 @@ template <> void VerilatedTrace<VL_DERIVED_T>::traceInit() VL_MT_UNSAFE {
    m_numSignals = 0;
    m_maxBits = 0;

-    // Call all initialize callbacks, which will call decl* for each signal.
-    for (vluint32_t ent = 0; ent < m_callbacks.size(); ++ent) {
-        VerilatedTraceCallInfo* cip = m_callbacks[ent];
-        cip->m_code = nextCode();
-        (cip->m_initcb)(self(), cip->m_userthis, cip->m_code);
+    // Call all initialize callbacks, which will:
+    // - Call decl* for each signal
+    // - Store the base code
+    for (vluint32_t i = 0; i < m_initCbs.size(); ++i) {
+        const CallbackRecord& cbr = m_initCbs[i];
+        cbr.m_initCb(cbr.m_userp, self(), nextCode());
    }

    if (expectedCodes && nextCode() != expectedCodes) {
@@ -350,6 +335,10 @@ template <> void VerilatedTrace<VL_DERIVED_T>::traceInit() VL_MT_UNSAFE {
    // holding previous signal values.
    if (!m_sigs_oldvalp) m_sigs_oldvalp = new vluint32_t[nextCode()];

+    // Set callback so flush/abort will flush this file
+    Verilated::addFlushCb(VerilatedTrace<VL_DERIVED_T>::onFlush, this);
+    Verilated::addExitCb(VerilatedTrace<VL_DERIVED_T>::onExit, this);
+
 #ifdef VL_TRACE_THREADED
    // Compute trace buffer size. we need to be able to store a new value for
    // each signal, which is 'nextCode()' entries after the init callbacks
@@ -409,12 +398,12 @@ template <> void VerilatedTrace<VL_DERIVED_T>::set_time_resolution(const std::st

 template <> void VerilatedTrace<VL_DERIVED_T>::dump(vluint64_t timeui) {
    m_assertOne.check();
-    if (VL_UNLIKELY(m_timeLastDump && timeui <= m_timeLastDump)) {
+    if (VL_UNCOVERABLE(m_timeLastDump && timeui <= m_timeLastDump)) {  // LCOV_EXCL_START
        VL_PRINTF_MT("%%Warning: previous dump at t=%" VL_PRI64 "u, requesting t=%" VL_PRI64
                     "u, dump call ignored\n",
                     m_timeLastDump, timeui);
        return;
-    }
+    }  // LCOV_EXCL_STOP
    m_timeLastDump = timeui;

    Verilated::quiesce();
@@ -452,17 +441,22 @@ template <> void VerilatedTrace<VL_DERIVED_T>::dump(vluint64_t timeui) {
    // Run the callbacks
    if (VL_UNLIKELY(m_fullDump)) {
        m_fullDump = false;  // No more need for next dump to be full
-        for (vluint32_t ent = 0; ent < m_callbacks.size(); ++ent) {
-            VerilatedTraceCallInfo* cip = m_callbacks[ent];
-            (cip->m_fullcb)(self(), cip->m_userthis, cip->m_code);
+        for (vluint32_t i = 0; i < m_fullCbs.size(); ++i) {
+            const CallbackRecord& cbr = m_fullCbs[i];
+            cbr.m_dumpCb(cbr.m_userp, self());
        }
    } else {
-        for (vluint32_t ent = 0; ent < m_callbacks.size(); ++ent) {
-            VerilatedTraceCallInfo* cip = m_callbacks[ent];
-            (cip->m_changecb)(self(), cip->m_userthis, cip->m_code);
+        for (vluint32_t i = 0; i < m_chgCbs.size(); ++i) {
+            const CallbackRecord& cbr = m_chgCbs[i];
+            cbr.m_dumpCb(cbr.m_userp, self());
        }
    }

+    for (vluint32_t i = 0; i < m_cleanupCbs.size(); ++i) {
+        const CallbackRecord& cbr = m_cleanupCbs[i];
+        cbr.m_dumpCb(cbr.m_userp, self());
+    }
+
 #ifdef VL_TRACE_THREADED
    if (VL_LIKELY(bufferp)) {
        // Mark end of the trace buffer we just filled
@@ -481,17 +475,32 @@ template <> void VerilatedTrace<VL_DERIVED_T>::dump(vluint64_t timeui) {
 // Non-hot path internal interface to Verilator generated code

 template <>
-void VerilatedTrace<VL_DERIVED_T>::addCallback(callback_t initcb, callback_t fullcb,
-                                               callback_t changecb,
-                                               void* userthis) VL_MT_UNSAFE_ONE {
+void VerilatedTrace<VL_DERIVED_T>::addCallbackRecord(std::vector<CallbackRecord>& cbVec,
+                                                     CallbackRecord& cbRec) {
    m_assertOne.check();
-    if (VL_UNLIKELY(timeLastDump() != 0)) {
+    if (VL_UNCOVERABLE(timeLastDump() != 0)) {  // LCOV_EXCL_START
        std::string msg = (std::string("Internal: ") + __FILE__ + "::" + __FUNCTION__
                           + " called with already open file");
        VL_FATAL_MT(__FILE__, __LINE__, "", msg.c_str());
-    }
-    VerilatedTraceCallInfo* cip = new VerilatedTraceCallInfo(initcb, fullcb, changecb, userthis);
-    m_callbacks.push_back(cip);
+    }  // LCOV_EXCL_STOP
+    cbVec.push_back(cbRec);
+}
+
+template <> void VerilatedTrace<VL_DERIVED_T>::addInitCb(initCb_t cb, void* userp) {
+    CallbackRecord cbr(cb, userp);
+    addCallbackRecord(m_initCbs, cbr);
+}
+template <> void VerilatedTrace<VL_DERIVED_T>::addFullCb(dumpCb_t cb, void* userp) {
+    CallbackRecord cbr(cb, userp);
+    addCallbackRecord(m_fullCbs, cbr);
+}
+template <> void VerilatedTrace<VL_DERIVED_T>::addChgCb(dumpCb_t cb, void* userp) {
+    CallbackRecord cbr(cb, userp);
+    addCallbackRecord(m_chgCbs, cbr);
+}
+template <> void VerilatedTrace<VL_DERIVED_T>::addCleanupCb(dumpCb_t cb, void* userp) {
+    CallbackRecord cbr(cb, userp);
+    addCallbackRecord(m_cleanupCbs, cbr);
 }

 //=========================================================================
@@ -537,12 +546,6 @@ void VerilatedTrace<VL_DERIVED_T>::fullWData(vluint32_t* oldp, const WData* newv
    self()->emitWData(oldp - m_sigs_oldvalp, newvalp, bits);
 }

-template <> void VerilatedTrace<VL_DERIVED_T>::fullFloat(vluint32_t* oldp, float newval) {
-    // cppcheck-suppress invalidPointerCast
-    *reinterpret_cast<float*>(oldp) = newval;
-    self()->emitFloat(oldp - m_sigs_oldvalp, newval);
-}
-
 template <> void VerilatedTrace<VL_DERIVED_T>::fullDouble(vluint32_t* oldp, double newval) {
    // cppcheck-suppress invalidPointerCast
    *reinterpret_cast<double*>(oldp) = newval;
@@ -1,497 +0,0 @@
-// -*- mode: C++; c-file-style: "cc-mode" -*-
-//*************************************************************************
-// DESCRIPTION: Verilator: pre-C++11 replacements for std::unordered_set
-//                         and std::unordered_map.
-//
-// Code available from: https://verilator.org
-//
-//*************************************************************************
-//
-// Copyright 2003-2020 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.
-// SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
-//
-//*************************************************************************
-
-//*************************************************************************
-// This file has clones of the std::unordered_set and std::unordered_map
-// hash table types. They are here so that Verilator can use hash tables
-// in pre-C++11 compilers, and the same client code can link against the
-// std:: types when they are available.
-//
-// The implementations in this file do not implement the complete APIs
-// of the std:: types. Nor are they correct in every detail,
-// notably, the const_iterators do not enforce constness. We can extend
-// these implementations to cover more of the std API as needed.
-//
-// TODO: In the future, when Verilator requires C++11 to compile,
-//       remove this entire file and switch to the std:: types.
-//
-//*************************************************************************
-
-#ifndef _V3_UNORDERED_SET_MAP_H_
-#define _V3_UNORDERED_SET_MAP_H_
-
-#include "verilatedos.h"
-
-#include <list>
-#include <stdexcept>
-#include <string>
-
-// Abstract 'vl_hash' and 'vl_equal_to' templates.
-template <typename T> struct vl_hash { size_t operator()(const T& k) const; };
-
-template <typename T> struct vl_equal_to { bool operator()(const T& a, const T& b) const; };
-
-// Specializations of 'vl_hash' and 'vl_equal_to'.
-inline size_t vl_hash_bytes(const void* vbufp, size_t nbytes) {
-    const vluint8_t* bufp = static_cast<const vluint8_t*>(vbufp);
-    size_t hash = 0;
-    for (size_t i = 0; i < nbytes; i++) {
-        hash = bufp[i] + 31U * hash;  // the K&R classic!
-    }
-    return hash;
-}
-
-template <> inline size_t vl_hash<unsigned int>::operator()(const unsigned int& k) const {
-    return k;
-}
-
-template <>
-inline bool vl_equal_to<unsigned int>::operator()(const unsigned int& a,
-                                                  const unsigned int& b) const {
-    return a == b;
-}
-
-template <> inline size_t vl_hash<std::string>::operator()(const std::string& k) const {
-    return vl_hash_bytes(k.data(), k.size());
-}
-
-template <>
-inline bool vl_equal_to<std::string>::operator()(const std::string& a,
-                                                 const std::string& b) const {
-    // Don't scan the strings if the sizes are different.
-    if (a.size() != b.size()) return false;
-    return (0 == a.compare(b));  // Must scan.
-}
-
-template <typename T> struct vl_hash<T*> {
-    size_t operator()(T* kp) const {
-        return ((sizeof(size_t) == sizeof(kp)) ? reinterpret_cast<size_t>(kp)
-                                               : vl_hash_bytes(&kp, sizeof(kp)));
-    }
-};
-
-template <typename T> struct vl_equal_to<T*> {
-    bool operator()(T* ap, T* bp) const { return ap == bp; }
-};
-
-//===================================================================
-//
-/// Functional clone of the std::unordered_set hash table.
-template <class T_Key, class T_Hash = vl_hash<T_Key>, class T_Equal = vl_equal_to<T_Key> >
-class vl_unordered_set {
-public:
-    // TYPES
-    typedef std::list<T_Key> Bucket;
-    enum RehashType { GROW, SHRINK };
-
-    template <class KK, class VV, class HH, class EQ> friend class vl_unordered_map;
-
-    class iterator {
-    protected:
-        // MEMBERS
-        size_t m_bucketIdx;  //  Bucket this iterator points into
-        typename Bucket::iterator m_bit;  // Bucket-local iterator
-        const vl_unordered_set* m_setp;  // The containing set
-
-    public:
-        // CONSTRUCTORS
-        iterator(size_t bucketIdx, typename Bucket::iterator bit, const vl_unordered_set* setp)
-            : m_bucketIdx(bucketIdx)
-            , m_bit(bit)
-            , m_setp(setp) {}
-
-        // METHODS
-        const T_Key& operator*() const { return *m_bit; }
-        // This should really be 'const T_Key*' type for unordered_set,
-        // however this iterator is shared with unordered_map whose
-        // operator-> returns a non-const ValueType*, so keep this
-        // non-const to avoid having to define a whole separate iterator
-        // for unordered_map.
-        T_Key* operator->() const { return &(*m_bit); }
-        bool operator==(const iterator& other) const {
-            return ((m_bucketIdx == other.m_bucketIdx) && (m_bit == other.m_bit));
-        }
-        bool operator!=(const iterator& other) const { return (!this->operator==(other)); }
-        void advanceUntilValid() {
-            while (true) {
-                if (m_bit != m_setp->m_bucketsp[m_bucketIdx].end()) {
-                    // Valid iterator in this bucket; we're done.
-                    return;
-                }
-
-                // Try the next bucket?
-                m_bucketIdx++;
-                if (m_bucketIdx == m_setp->numBuckets()) {
-                    // Ran past the end of buckets, set to end().
-                    *this = m_setp->end();
-                    return;
-                }
-                m_bit = m_setp->m_bucketsp[m_bucketIdx].begin();
-            }
-        }
-        void operator++() {
-            ++m_bit;
-            advanceUntilValid();
-        }
-
-        typename Bucket::iterator bit() const { return m_bit; }
-    };
-
-    // TODO: there's no real const enforcement on the 'const_iterator'.
-    typedef iterator const_iterator;
-
-private:
-    // MEMBERS
-    size_t m_numElements;  //  Number of entries present.
-    size_t m_log2Buckets;  //  Log-base-2 of the number of buckets.
-    mutable Bucket* m_bucketsp;  //  Hash table buckets. May be NULL;
-    //                          //   we'll allocate it on the fly when
-    //                          //   the first entries are created.
-    Bucket m_emptyBucket;  //  A fake bucket, used to construct end().
-    T_Hash m_hash;  //  Hash function provider.
-    T_Equal m_equal;  //  Equal-to function provider.
-
-public:
-    // CONSTRUCTORS
-    vl_unordered_set()
-        : m_numElements(0)
-        , m_log2Buckets(initLog2Buckets())
-        , m_bucketsp(NULL)
-        , m_hash()
-        , m_equal() {}
-
-    vl_unordered_set(const vl_unordered_set& other)
-        : m_numElements(other.m_numElements)
-        , m_log2Buckets(other.m_log2Buckets)
-        , m_bucketsp(NULL)
-        , m_hash()
-        , m_equal() {
-        if (other.m_bucketsp) {
-            m_bucketsp = new Bucket[numBuckets()];
-            for (size_t i = 0; i < numBuckets(); i++) m_bucketsp[i] = other.m_bucketsp[i];
-        }
-    }
-    ~vl_unordered_set() { VL_DO_DANGLING(delete[] m_bucketsp, m_bucketsp); }
-
-    vl_unordered_set& operator=(const vl_unordered_set& other) {
-        if (this != &other) {
-            clear();
-            delete[] m_bucketsp;
-            m_numElements = other.m_numElements;
-            m_log2Buckets = other.m_log2Buckets;
-            if (other.m_bucketsp) {
-                m_bucketsp = new Bucket[numBuckets()];
-                for (size_t i = 0; i < numBuckets(); i++) m_bucketsp[i] = other.m_bucketsp[i];
-            } else {
-                m_bucketsp = NULL;
-            }
-        }
-        return *this;
-    }
-
-    // METHODS
-    static size_t initLog2Buckets() { return 4; }
-
-    iterator begin() {
-        if (m_numElements) {
-            initBuckets();
-            iterator result = iterator(0, m_bucketsp[0].begin(), this);
-            result.advanceUntilValid();
-            return result;
-        }
-        return end();
-    }
-    const_iterator begin() const {
-        if (m_numElements) {
-            initBuckets();
-            const_iterator result = iterator(0, m_bucketsp[0].begin(), this);
-            result.advanceUntilValid();
-            return result;
-        }
-        return end();
-    }
-    const_iterator end() const {
-        return iterator(VL_ULL(0xFFFFFFFFFFFFFFFF), const_cast<Bucket&>(m_emptyBucket).begin(),
-                        this);
-    }
-
-    bool empty() const { return m_numElements == 0; }
-
-    size_t size() const { return m_numElements; }
-
-    size_t count(const T_Key& key) const { return (find(key) == end()) ? 0 : 1; }
-
-    size_t hashToBucket(size_t hashVal) const { return hashToBucket(hashVal, m_log2Buckets); }
-    static size_t hashToBucket(size_t hashVal, unsigned log2Buckets) {
-        // Fibonacci hashing, see
-        // https://probablydance.com/2018/06/16/fibonacci-hashing-the-optimization
-        // -that-the-world-forgot-or-a-better-alternative-to-integer-modulo/
-        //
-        // * The magic numbers below are UINT_MAX/phi where phi is the
-        //   golden ratio number (1.618...)  for either 64- or 32-bit
-        //   values of UINT_MAX.
-        //
-        // * Fibonacci hashing mixes the result of the client's hash
-        //   function further. This permits the use of very fast client
-        //   hash funcs (like just returning the int or pointer value as
-        //   is!) and tolerates crappy client hash functions pretty well.
-        size_t mult
-            = hashVal * ((sizeof(size_t) == 8) ? VL_ULL(11400714819323198485) : 2654435769lu);
-        size_t result = (mult >> (((sizeof(size_t) == 8) ? 64 : 32) - log2Buckets));
-        return result;
-    }
-
-    iterator find_internal(const T_Key& key, size_t& bucketIdxOut) {
-        size_t hash = m_hash.operator()(key);
-        bucketIdxOut = hashToBucket(hash);
-        initBuckets();
-        Bucket* bucketp = &m_bucketsp[bucketIdxOut];
-
-        for (typename Bucket::iterator it = bucketp->begin(); it != bucketp->end(); ++it) {
-            if (m_equal.operator()(*it, key)) return iterator(bucketIdxOut, it, this);
-        }
-        return end();
-    }
-
-    const_iterator find(const T_Key& key) const {
-        size_t bucketIdx;
-        return const_cast<vl_unordered_set*>(this)->find_internal(key, bucketIdx);
-    }
-
-    iterator find(const T_Key& key) {
-        size_t bucketIdx;
-        return find_internal(key, bucketIdx);
-    }
-
-    std::pair<iterator, bool> insert(const T_Key& val) {
-        size_t bucketIdx;
-        iterator existIt = find_internal(val, bucketIdx);
-        if (existIt != end()) {
-            // Collision with existing element.
-            //
-            // An element may be inserted only if it is not
-            // equal to an existing element. So fail.
-            return std::pair<iterator, bool>(end(), false);
-        }
-
-        // No collision, so insert it.
-        m_numElements++;
-
-        m_bucketsp[bucketIdx].push_front(val);
-
-        // Compute result iterator. This pointer will be valid
-        // if we don't rehash:
-        iterator result_it(bucketIdx, m_bucketsp[bucketIdx].begin(), this);
-
-        if (needToRehash(GROW)) {
-            rehash(GROW);
-            // ... since we rehashed, do a lookup to get the result iterator.
-            result_it = find(val);
-        }
-
-        return std::pair<iterator, bool>(result_it, true);
-    }
-
-    iterator erase(iterator it) {
-        iterator next_it = it;
-        ++next_it;
-        erase(*it);
-        return next_it;
-    }
-
-    size_t erase(const T_Key& key) {
-        size_t bucketIdx;
-        iterator it = find_internal(key, bucketIdx);
-        if (it != end()) {
-            m_bucketsp[bucketIdx].erase(it.bit());
-            m_numElements--;
-            // Rehashing to handle a shrinking data set is important
-            // for the Scoreboard in V3Partition, which begins tracking
-            // a huge number of vertices and then tracks a successively
-            // smaller number over time.
-            if (needToRehash(SHRINK)) rehash(SHRINK);
-            return 1;
-        }
-        return 0;
-    }
-
-    void clear() {
-        if (m_bucketsp) {
-            delete[] m_bucketsp;
-            m_bucketsp = NULL;
-        }
-        m_numElements = 0;
-        m_log2Buckets = initLog2Buckets();
-    }
-
-private:
-    size_t numBuckets() const { return (VL_ULL(1) << m_log2Buckets); }
-
-    Bucket* getBucket(size_t idx) {
-        initBuckets();
-        return &m_bucketsp[idx];
-    }
-
-    void initBuckets() const {
-        if (!m_bucketsp) m_bucketsp = new Bucket[numBuckets()];
-    }
-
-    bool needToRehash(RehashType rt) const {
-        if (rt == GROW) {
-            return ((4 * numBuckets()) < m_numElements);
-        } else {
-            return (numBuckets() > (4 * m_numElements));
-        }
-    }
-
-    void rehash(RehashType rt) {
-        size_t new_log2Buckets;
-        if (rt == GROW) {
-            new_log2Buckets = m_log2Buckets + 2;
-        } else {
-            if (m_log2Buckets <= 4) {
-                // On shrink, saturate m_log2Buckets at its
-                // initial size of 2^4 == 16 buckets. Don't risk
-                // underflowing!
-                return;
-            }
-            new_log2Buckets = m_log2Buckets - 2;
-        }
-
-        size_t new_num_buckets = VL_ULL(1) << new_log2Buckets;
-        Bucket* new_bucketsp = new Bucket[new_num_buckets];
-
-        for (size_t i = 0; i < numBuckets(); i++) {
-            while (!m_bucketsp[i].empty()) {
-                typename Bucket::iterator bit = m_bucketsp[i].begin();
-                size_t hash = m_hash.operator()(*bit);
-                size_t new_idx = hashToBucket(hash, new_log2Buckets);
-                // Avoid mallocing one list elem and freeing another;
-                // splice just moves it over.
-                new_bucketsp[new_idx].splice(new_bucketsp[new_idx].begin(), m_bucketsp[i], bit);
-            }
-        }
-
-        delete[] m_bucketsp;
-        m_bucketsp = new_bucketsp;
-        m_log2Buckets = new_log2Buckets;
-    }
-};
-
-//===================================================================
-//
-/// Functional clone of the std::unordered_map hash table.
-template <class T_Key, class T_Value, class T_Hash = vl_hash<T_Key>,
-          class T_Equal = vl_equal_to<T_Key> >
-class vl_unordered_map {
-private:
-    // TYPES
-    typedef std::pair<T_Key, T_Value> KeyValPair;
-
-    class KeyHash {
-    private:
-        T_Hash key_hash;
-
-    public:
-        KeyHash() {}
-        size_t operator()(const KeyValPair& kv_pair) const {
-            return key_hash.operator()(kv_pair.first);
-        }
-    };
-
-    class KeyEqual {
-    private:
-        T_Equal key_eq;
-
-    public:
-        KeyEqual() {}
-        bool operator()(const KeyValPair& kv_a, const KeyValPair& kv_b) const {
-            return key_eq.operator()(kv_a.first, kv_b.first);
-        }
-    };
-
-    // MEMBERS
-    typedef vl_unordered_set<KeyValPair, KeyHash, KeyEqual> MapSet;
-    MapSet m_set;  // Wrap this vl_unordered_set which holds all state.
-
-public:
-    // CONSTRUCTORS
-    vl_unordered_map() {}
-    ~vl_unordered_map() {}
-
-    typedef typename MapSet::iterator iterator;
-    typedef typename MapSet::const_iterator const_iterator;
-
-    // METHODS
-    iterator begin() { return m_set.begin(); }
-    const_iterator begin() const { return m_set.begin(); }
-    const_iterator end() const { return m_set.end(); }
-    bool empty() const { return m_set.empty(); }
-    iterator find(const T_Key& k) {
-        // We can't assume that T_Value() is defined.
-        // ie, this does not work:
-        //    return m_set.find(std::make_pair(k, T_Value()));
-
-        // So, do this instead:
-        T_Hash mapHash;
-        T_Equal mapEq;
-        size_t hash = mapHash.operator()(k);
-        size_t bucketIdxOut = m_set.hashToBucket(hash);
-        typename MapSet::Bucket* bucketp = m_set.getBucket(bucketIdxOut);
-
-        for (typename MapSet::Bucket::iterator it = bucketp->begin(); it != bucketp->end(); ++it) {
-            if (mapEq.operator()(it->first, k)) return iterator(bucketIdxOut, it, &m_set);
-        }
-        return end();
-    }
-    const_iterator find(const T_Key& k) const {
-        return const_cast<vl_unordered_map*>(this)->find(k);
-    }
-    std::pair<iterator, bool> insert(const KeyValPair& val) { return m_set.insert(val); }
-    iterator erase(iterator it) { return m_set.erase(it); }
-    size_t erase(const T_Key& k) {
-        iterator it = find(k);
-        if (it == end()) return 0;
-        m_set.erase(it);
-        return 1;
-    }
-    T_Value& operator[](const T_Key& k) {
-        // Here we can assume T_Value() is defined, as
-        // std::unordered_map::operator[] relies on it too.
-        KeyValPair dummy = std::make_pair(k, T_Value());
-        iterator it = m_set.find(dummy);
-        if (it == m_set.end()) it = m_set.insert(dummy).first;
-        // For the 'set', it's generally not safe to modify
-        // the value after deref. For the 'map' though, we know
-        // it's safe to modify the value field and we can allow it:
-        return it->second;
-    }
-    T_Value& at(const T_Key& k) {
-        iterator it = find(k);
-        if (it == end()) { throw std::out_of_range("sorry"); }
-        return it->second;
-    }
-    const T_Value& at(const T_Key& k) const {
-        iterator it = find(k);
-        if (it == end()) { throw std::out_of_range("sorry"); }
-        return it->second;
-    }
-    void clear() { m_set.clear(); }
-    size_t size() const { return m_set.size(); }
-};
-
-#endif
@@ -27,7 +27,6 @@
 #include <cerrno>
 #include <ctime>
 #include <fcntl.h>
-#include <sys/stat.h>

 #if defined(_WIN32) && !defined(__MINGW32__) && !defined(__CYGWIN__)
 # include <io.h>
@@ -35,8 +34,6 @@
 # include <unistd.h>
 #endif

-#include "verilated_intrinsics.h"
-
 // SPDIFF_ON

 #ifndef O_LARGEFILE  // For example on WIN32
@@ -54,13 +51,14 @@
 // This size comes form VCD allowing use of printable ASCII characters between
 // '!' and '~' inclusive, which are a total of 94 different values. Encoding a
 // 32 bit code hence needs a maximum of ceil(log94(2**32-1)) == 5 bytes.
-#define VL_TRACE_MAX_VCD_CODE_SIZE 5  ///< Maximum length of a VCD string code
+constexpr unsigned VL_TRACE_MAX_VCD_CODE_SIZE = 5;  ///< Maximum length of a VCD string code
+
 // We use 8 bytes per code in a suffix buffer array.
 // 1 byte optional separator + VL_TRACE_MAX_VCD_CODE_SIZE bytes for code
 // + 1 byte '\n' + 1 byte suffix size. This luckily comes out to a power of 2,
 // meaning the array can be aligned such that entries never straddle multiple
 // cache-lines.
-#define VL_TRACE_SUFFIX_ENTRY_SIZE 8  ///< Size of a suffix entry
+constexpr unsigned VL_TRACE_SUFFIX_ENTRY_SIZE = 8;  ///< Size of a suffix entry

 //=============================================================================
 // Specialization of the generics for this trace format
@@ -69,47 +67,6 @@
 #include "verilated_trace_imp.cpp"
 #undef VL_DERIVED_T

-//=============================================================================
-// VerilatedVcdImp
-/// Base class to hold some static state
-/// This is an internally used class
-
-class VerilatedVcdSingleton {
-private:
-    typedef std::vector<VerilatedVcd*> VcdVec;
-    struct Singleton {
-        VerilatedMutex s_vcdMutex;  ///< Protect the singleton
-        VcdVec s_vcdVecp VL_GUARDED_BY(s_vcdMutex);  ///< List of all created traces
-    };
-    static Singleton& singleton() {
-        static Singleton s;
-        return s;
-    }
-
-public:
-    static void pushVcd(VerilatedVcd* vcdp) VL_EXCLUDES(singleton().s_vcdMutex) {
-        VerilatedLockGuard lock(singleton().s_vcdMutex);
-        singleton().s_vcdVecp.push_back(vcdp);
-    }
-    static void removeVcd(const VerilatedVcd* vcdp) VL_EXCLUDES(singleton().s_vcdMutex) {
-        VerilatedLockGuard lock(singleton().s_vcdMutex);
-        VcdVec::iterator pos
-            = find(singleton().s_vcdVecp.begin(), singleton().s_vcdVecp.end(), vcdp);
-        if (pos != singleton().s_vcdVecp.end()) { singleton().s_vcdVecp.erase(pos); }
-    }
-    static void flush_all() VL_EXCLUDES(singleton().s_vcdMutex) VL_MT_UNSAFE_ONE {
-        // Thread safety: Although this function is protected by a mutex so
-        // perhaps in the future we can allow tracing in separate threads,
-        // vcdp->flush() assumes call from single thread
-        VerilatedLockGuard lock(singleton().s_vcdMutex);
-        for (VcdVec::const_iterator it = singleton().s_vcdVecp.begin();
-             it != singleton().s_vcdVecp.end(); ++it) {
-            VerilatedVcd* vcdp = *it;
-            vcdp->flush();
-        }
-    }
-};
-
 //=============================================================================
 //=============================================================================
 //=============================================================================
@@ -132,21 +89,15 @@ ssize_t VerilatedVcdFile::write(const char* bufp, ssize_t len) VL_MT_UNSAFE {
 //=============================================================================
 // Opening/Closing

-VerilatedVcd::VerilatedVcd(VerilatedVcdFile* filep)
-    : m_isOpen(false)
-    , m_rolloverMB(0)
-    , m_modDepth(0) {
+VerilatedVcd::VerilatedVcd(VerilatedVcdFile* filep) {
    // Not in header to avoid link issue if header is included without this .cpp file
-    m_fileNewed = (filep == NULL);
+    m_fileNewed = (filep == nullptr);
    m_filep = m_fileNewed ? new VerilatedVcdFile : filep;
-    m_namemapp = NULL;
-    m_evcd = false;
    m_wrChunkSize = 8 * 1024;
    m_wrBufp = new char[m_wrChunkSize * 8];
    m_wrFlushp = m_wrBufp + m_wrChunkSize * 6;
    m_writep = m_wrBufp;
-    m_wroteBytes = 0;
-    m_suffixesp = NULL;
+    m_suffixesp = nullptr;
 }

 void VerilatedVcd::open(const char* filename) {
@@ -155,13 +106,7 @@ void VerilatedVcd::open(const char* filename) {

    // Set member variables
    m_filename = filename;  // "" is ok, as someone may overload open
-    VerilatedVcdSingleton::pushVcd(this);

-    // SPDIFF_OFF
-    // Set callback so an early exit will flush us
-    Verilated::flushCb(&flush_all);
-
-    // SPDIFF_ON
    openNext(m_rolloverMB != 0);
    if (!isOpen()) return;

@@ -203,8 +148,8 @@ void VerilatedVcd::openNext(bool incFilename) {
        }
        m_filename = name;
    }
-    if (m_filename[0] == '|') {
-        assert(0);  // Not supported yet.
+    if (VL_UNCOVERABLE(m_filename[0] == '|')) {
+        assert(0);  // LCOV_EXCL_LINE // Not supported yet.
    } else {
        // cppcheck-suppress duplicateExpression
        if (!m_filep->open(m_filename)) {
@@ -241,15 +186,15 @@ void VerilatedVcd::makeNameMap() {
    // If no scope was specified, prefix everything with a "top"
    // This comes from user instantiations with no name - IE Vtop("").
    bool nullScope = false;
-    for (NameMap::const_iterator it = m_namemapp->begin(); it != m_namemapp->end(); ++it) {
-        const std::string& hiername = it->first;
+    for (const auto& i : *m_namemapp) {
+        const std::string& hiername = i.first;
        if (!hiername.empty() && hiername[0] == '\t') nullScope = true;
    }
    if (nullScope) {
        NameMap* newmapp = new NameMap;
-        for (NameMap::const_iterator it = m_namemapp->begin(); it != m_namemapp->end(); ++it) {
-            const std::string& hiername = it->first;
-            const std::string& decl = it->second;
+        for (const auto& i : *m_namemapp) {
+            const std::string& hiername = i.first;
+            const std::string& decl = i.second;
            std::string newname = std::string("top");
            if (hiername[0] != '\t') newname += ' ';
            newname += hiername;
@@ -261,15 +206,14 @@ void VerilatedVcd::makeNameMap() {
 }

 void VerilatedVcd::deleteNameMap() {
-    if (m_namemapp) VL_DO_CLEAR(delete m_namemapp, m_namemapp = NULL);
+    if (m_namemapp) VL_DO_CLEAR(delete m_namemapp, m_namemapp = nullptr);
 }

 VerilatedVcd::~VerilatedVcd() {
    close();
-    if (m_wrBufp) VL_DO_CLEAR(delete[] m_wrBufp, m_wrBufp = NULL);
+    if (m_wrBufp) VL_DO_CLEAR(delete[] m_wrBufp, m_wrBufp = nullptr);
    deleteNameMap();
-    if (m_filep && m_fileNewed) VL_DO_CLEAR(delete m_filep, m_filep = NULL);
-    VerilatedVcdSingleton::removeVcd(this);
+    if (m_filep && m_fileNewed) VL_DO_CLEAR(delete m_filep, m_filep = nullptr);
 }

 void VerilatedVcd::closePrev() {
@@ -337,7 +281,7 @@ void VerilatedVcd::bufferResize(vluint64_t minsize) {
        memcpy(m_wrBufp, oldbufp, m_writep - oldbufp);
        m_writep = m_wrBufp + (m_writep - oldbufp);
        m_wrFlushp = m_wrBufp + m_wrChunkSize * 6;
-        VL_DO_CLEAR(delete[] oldbufp, oldbufp = NULL);
+        VL_DO_CLEAR(delete[] oldbufp, oldbufp = nullptr);
    }
 }

@@ -358,13 +302,15 @@ void VerilatedVcd::bufferFlush() VL_MT_UNSAFE_ONE {
        if (got > 0) {
            wp += got;
            m_wroteBytes += got;
-        } else if (got < 0) {
-            if (errno != EAGAIN && errno != EINTR) {
+        } else if (VL_UNCOVERABLE(got < 0)) {
+            if (VL_UNCOVERABLE(errno != EAGAIN && errno != EINTR)) {
+                // LCOV_EXCL_START
                // write failed, presume error (perhaps out of disk space)
                std::string msg = std::string("VerilatedVcd::bufferFlush: ") + strerror(errno);
                VL_FATAL_MT("", 0, "", msg.c_str());
                closeErr();
                break;
+                // LCOV_EXCL_STOP
            }
        }
    }
@@ -399,7 +345,7 @@ void VerilatedVcd::printIndent(int level_change) {

 void VerilatedVcd::dumpHeader() {
    printStr("$version Generated by VerilatedVcd $end\n");
-    time_t time_str = time(NULL);
+    time_t time_str = time(nullptr);
    printStr("$date ");
    printStr(ctime(&time_str));
    printStr(" $end\n");
@@ -422,9 +368,9 @@ void VerilatedVcd::dumpHeader() {

    // Print the signal names
    const char* lastName = "";
-    for (NameMap::const_iterator it = m_namemapp->begin(); it != m_namemapp->end(); ++it) {
-        const std::string& hiernamestr = it->first;
-        const std::string& decl = it->second;
+    for (const auto& i : *m_namemapp) {
+        const std::string& hiernamestr = i.first;
+        const std::string& decl = i.second;

        // Determine difference between the old and new names
        const char* hiername = hiernamestr.c_str();
@@ -583,9 +529,6 @@ void VerilatedVcd::declArray(vluint32_t code, const char* name, bool array, int
                             int lsb) {
    declare(code, name, "wire", array, arraynum, false, true, msb, lsb);
 }
-void VerilatedVcd::declFloat(vluint32_t code, const char* name, bool array, int arraynum) {
-    declare(code, name, "real", array, arraynum, false, false, 31, 0);
-}
 void VerilatedVcd::declDouble(vluint32_t code, const char* name, bool array, int arraynum) {
    declare(code, name, "real", array, arraynum, false, false, 63, 0);
 }
@@ -699,15 +642,6 @@ void VerilatedVcd::emitWData(vluint32_t code, const WData* newvalp, int bits) {
    finishLine(code, wp);
 }

-VL_ATTR_ALWINLINE
-void VerilatedVcd::emitFloat(vluint32_t code, float newval) {
-    char* wp = m_writep;
-    // Buffer can't overflow before sprintf; we sized during declaration
-    sprintf(wp, "r%.16g", static_cast<double>(newval));
-    wp += strlen(wp);
-    finishLine(code, wp);
-}
-
 VL_ATTR_ALWINLINE
 void VerilatedVcd::emitDouble(vluint32_t code, double newval) {
    char* wp = m_writep;
@@ -742,7 +676,7 @@ void VerilatedVcd::fullQuad(vluint32_t code, const vluint64_t newval, int bits)
    (*(reinterpret_cast<vluint64_t*>(oldp(code)))) = newval;
    *m_writep++ = 'b';
    for (int bit = bits - 1; bit >= 0; --bit) {
-        *m_writep++ = ((newval & (VL_ULL(1) << bit)) ? '1' : '0');
+        *m_writep++ = ((newval & (1ULL << bit)) ? '1' : '0');
    }
    *m_writep++ = ' ';
    m_writep = writeCode(m_writep, code);
@@ -764,7 +698,7 @@ void VerilatedVcd::fullArray(vluint32_t code, const vluint64_t* newval, int bits
    for (int word = 0; word < (((bits - 1) / 64) + 1); ++word) { oldp(code)[word] = newval[word]; }
    *m_writep++ = 'b';
    for (int bit = bits - 1; bit >= 0; --bit) {
-        *m_writep++ = ((newval[(bit / 64)] & (VL_ULL(1) << (bit & 0x3f))) ? '1' : '0');
+        *m_writep++ = ((newval[(bit / 64)] & (1ULL << (bit & 0x3f))) ? '1' : '0');
    }
    *m_writep++ = ' ';
    m_writep = writeCode(m_writep, code);
@@ -792,14 +726,13 @@ void VerilatedVcd::fullTriBus(vluint32_t code, const vluint32_t newval, const vl
    *m_writep++ = '\n';
    bufferCheck();
 }
-void VerilatedVcd::fullTriQuad(vluint32_t code, const vluint64_t newval, const vluint32_t newtri,
+void VerilatedVcd::fullTriQuad(vluint32_t code, const vluint64_t newval, const vluint64_t newtri,
                               int bits) {
    (*(reinterpret_cast<vluint64_t*>(oldp(code)))) = newval;
    (*(reinterpret_cast<vluint64_t*>(oldp(code + 1)))) = newtri;
    *m_writep++ = 'b';
    for (int bit = bits - 1; bit >= 0; --bit) {
-        *m_writep++
-            = "01zz"[((newval >> bit) & VL_ULL(1)) | (((newtri >> bit) & VL_ULL(1)) << VL_ULL(1))];
+        *m_writep++ = "01zz"[((newval >> bit) & 1ULL) | (((newtri >> bit) & 1ULL) << 1ULL)];
    }
    *m_writep++ = ' ';
    m_writep = writeCode(m_writep, code);
@@ -834,46 +767,12 @@ void VerilatedVcd::fullDouble(vluint32_t code, const double newval) {
    *m_writep++ = '\n';
    bufferCheck();
 }
-void VerilatedVcd::fullFloat(vluint32_t code, const float newval) {
-    // cppcheck-suppress invalidPointerCast
-    (*(reinterpret_cast<float*>(oldp(code)))) = newval;
-    // Buffer can't overflow before sprintf; we sized during declaration
-    sprintf(m_writep, "r%.16g", static_cast<double>(newval));
-    m_writep += strlen(m_writep);
-    *m_writep++ = ' ';
-    m_writep = writeCode(m_writep, code);
-    *m_writep++ = '\n';
-    bufferCheck();
-}
-void VerilatedVcd::fullBitX(vluint32_t code) {
-    *m_writep++ = 'x';
-    m_writep = writeCode(m_writep, code);
-    *m_writep++ = '\n';
-    bufferCheck();
-}
-void VerilatedVcd::fullBusX(vluint32_t code, int bits) {
-    *m_writep++ = 'b';
-    for (int bit = bits - 1; bit >= 0; --bit) *m_writep++ = 'x';
-    *m_writep++ = ' ';
-    m_writep = writeCode(m_writep, code);
-    *m_writep++ = '\n';
-    bufferCheck();
-}
-void VerilatedVcd::fullQuadX(vluint32_t code, int bits) { fullBusX(code, bits); }
-void VerilatedVcd::fullArrayX(vluint32_t code, int bits) { fullBusX(code, bits); }

 #endif  // VL_TRACE_VCD_OLD_API

 //======================================================================
-// Static members
-
-void VerilatedVcd::flush_all() VL_MT_UNSAFE_ONE { VerilatedVcdSingleton::flush_all(); }
-
 //======================================================================
 //======================================================================
-//======================================================================
-
-// clang-format off

 #ifdef VERILATED_VCD_TEST
 #include <iostream>
@@ -882,34 +781,39 @@ vluint32_t v1, v2, s1, s2[3];
 vluint32_t tri96[3];
 vluint32_t tri96__tri[3];
 vluint64_t quad96[2];
+vluint64_t tquad;
+vluint64_t tquad__tri;
 vluint8_t ch;
 vluint64_t timestamp = 1;
-double doub = 0;
+double doub = 0.0;
+float flo = 0.0f;

-void vcdInit(VerilatedVcd* vcdp, void* userthis, vluint32_t code) {
+void vcdInit(void*, VerilatedVcd* vcdp, vluint32_t) {
    vcdp->scopeEscape('.');
    vcdp->module("top");
-     vcdp->declBus(0x2, "v1",-1,5,1);
-     vcdp->declBus(0x3, "v2",-1,6,0);
-     vcdp->module("top.sub1");
-      vcdp->declBit(0x4, "s1",-1);
-      vcdp->declBit(0x5, "ch",-1);
-     vcdp->module("top.sub2");
-      vcdp->declArray(0x6, "s2",-1, 40,3);
+    /**/ vcdp->declBus(0x2, "v1", -1, 0, 5, 1);
+    /**/ vcdp->declBus(0x3, "v2", -1, 0, 6, 1);
+    /**/ vcdp->module("top.sub1");
+    /***/ vcdp->declBit(0x4, "s1", -1, 0);
+    /***/ vcdp->declBit(0x5, "ch", -1, 0);
+    /**/ vcdp->module("top.sub2");
+    /***/ vcdp->declArray(0x6, "s2", -1, 0, 40, 3);
    // Note need to add 3 for next code.
    vcdp->module("top2");
-     vcdp->declBus(0x2, "t2v1",-1,4,1);
-     vcdp->declTriBit(0x10, "io1",-1);
-     vcdp->declTriBus(0x12, "io5",-1,4,0);
-     vcdp->declTriArray(0x16, "io96",-1,95,0);
-    // Note need to add 6 for next code.
-     vcdp->declDouble(0x1c, "doub",-1);
-    // Note need to add 2 for next code.
-     vcdp->declArray(0x1e, "q2",-1,95,0);
-    // Note need to add 4 for next code.
+    /**/ vcdp->declBus(0x2, "t2v1", -1, 0, 4, 1);
+    /**/ vcdp->declTriBit(0x10, "io1", -1, 0);
+    /**/ vcdp->declTriBus(0x12, "io5", -1, 0, 4, 0);
+    /**/ vcdp->declTriArray(0x16, "io96", -1, 0, 95, 0);
+    /**/  // Note need to add 6 for next code.
+    /**/ vcdp->declDouble(0x1c, "doub", -1, 0);
+    /**/  // Note need to add 2 for next code.
+    /**/ vcdp->declArray(0x20, "q2", -1, 0, 95, 0);
+    /**/  // Note need to add 4 for next code.
+    /**/ vcdp->declTriQuad(0x24, "tq", -1, 0, 63, 0);
+    /**/  // Note need to add 4 for next code.
 }

-void vcdFull(VerilatedVcd* vcdp, void* userthis, vluint32_t code) {
+void vcdFull(void*, VerilatedVcd* vcdp) {
    vcdp->fullBus(0x2, v1, 5);
    vcdp->fullBus(0x3, v2, 7);
    vcdp->fullBit(0x4, s1);
@@ -919,10 +823,11 @@ void vcdFull(VerilatedVcd* vcdp, void* userthis, vluint32_t code) {
    vcdp->fullTriBus(0x12, tri96[0] & 0x1f, tri96__tri[0] & 0x1f, 5);
    vcdp->fullTriArray(0x16, tri96, tri96__tri, 96);
    vcdp->fullDouble(0x1c, doub);
-    vcdp->fullArray(0x1e, &quad96[0], 96);
+    vcdp->fullArray(0x20, &quad96[0], 96);
+    vcdp->fullTriQuad(0x24, tquad, tquad__tri, 64);
 }

-void vcdChange(VerilatedVcd* vcdp, void* userthis, vluint32_t code) {
+void vcdChange(void*, VerilatedVcd* vcdp) {
    vcdp->chgBus(0x2, v1, 5);
    vcdp->chgBus(0x3, v2, 7);
    vcdp->chgBit(0x4, s1);
@@ -932,12 +837,12 @@ void vcdChange(VerilatedVcd* vcdp, void* userthis, vluint32_t code) {
    vcdp->chgTriBus(0x12, tri96[0] & 0x1f, tri96__tri[0] & 0x1f, 5);
    vcdp->chgTriArray(0x16, tri96, tri96__tri, 96);
    vcdp->chgDouble(0x1c, doub);
-    vcdp->chgArray(0x1e, &quad96[0], 96);
+    vcdp->chgArray(0x20, &quad96[0], 96);
+    vcdp->chgTriQuad(0x24, tquad, tquad__tri, 64);
 }

-main() {
-    std::cout << "test: O_LARGEFILE=" << O_LARGEFILE << std::endl;
-
+// clang-format off
+void vcdTestMain(const char* filenamep) {
    v1 = v2 = s1 = 0;
    s2[0] = s2[1] = s2[2] = 0;
    tri96[2] = tri96[1] = tri96[0] = 0;
@@ -945,43 +850,52 @@ main() {
    quad96[1] = quad96[0] = 0;
    ch = 0;
    doub = 0;
+    tquad = tquad__tri = 0;
    {
        VerilatedVcdC* vcdp = new VerilatedVcdC;
-        vcdp->spTrace()->addCallback(&vcdInit, &vcdFull, &vcdChange, 0);
-        vcdp->open("test.vcd");
+        vcdp->evcd(true);
+        vcdp->spTrace()->addInitCb(&vcdInit, 0);
+        vcdp->spTrace()->addFullCb(&vcdFull, 0);
+        vcdp->spTrace()->addChgCb(&vcdChange, 0);
+        vcdp->open(filenamep);
        // Dumping
-        vcdp->dump(timestamp++);
+        vcdp->dump(++timestamp);
        v1 = 0xfff;
        tri96[2] = 4; tri96[1] = 2; tri96[0] = 1;
        tri96__tri[2] = tri96__tri[1] = tri96__tri[0] = ~0;  // Still tri
        quad96[1] = 0xffffffff; quad96[0] = 0;
        doub = 1.5;
-        vcdp->dump(timestamp++);
+        flo = 1.4f;
+        vcdp->dump(++timestamp);
        v2 = 0x1;
        s2[1] = 2;
        tri96__tri[2] = tri96__tri[1] = tri96__tri[0] = 0;  // enable w/o data change
        quad96[1] = 0; quad96[0] = ~0;
        doub = -1.66e13;
-        vcdp->dump(timestamp++);
+        flo = 0.123f;
+        tquad = 0x00ff00ff00ff00ffULL;
+        tquad__tri = 0x0000fffff0000ffffULL;
+        vcdp->dump(++timestamp);
        ch = 2;
        tri96[2] = ~4; tri96[1] = ~2; tri96[0] = ~1;
        doub = -3.33e-13;
-        vcdp->dump(timestamp++);
-        vcdp->dump(timestamp++);
+        vcdp->dump(++timestamp);
+        vcdp->dump(++timestamp);
 # ifdef VERILATED_VCD_TEST_64BIT
-        vluint64_t bytesPerDump = VL_ULL(15);
-        for (vluint64_t i = 0; i < ((VL_ULL(1) << 32) / bytesPerDump); i++) {
+        vluint64_t bytesPerDump = 15ULL;
+        for (vluint64_t i = 0; i < ((1ULL << 32) / bytesPerDump); i++) {
            v1 = i;
-            vcdp->dump(timestamp++);
+            vcdp->dump(++timestamp);
        }
 # endif
        vcdp->close();
    }
 }
 #endif
+// clang-format on

 //********************************************************************
-// ;compile-command: "mkdir -p ../test_dir && cd ../test_dir && c++ -DVERILATED_VCD_TEST ../include/verilated_vcd_c.cpp -o verilated_vcd_c && ./verilated_vcd_c && cat test.vcd"
+// ;compile-command: "v4make test_regress/t/t_trace_c_api.pl"
 //
 // Local Variables:
 // End:
@@ -36,11 +36,10 @@ class VerilatedVcd;

 class VerilatedVcdFile {
 private:
-    int m_fd;  ///< File descriptor we're writing to
+    int m_fd = 0;  ///< File descriptor we're writing to
 public:
    // METHODS
-    VerilatedVcdFile()
-        : m_fd(0) {}
+    VerilatedVcdFile() {}
    virtual ~VerilatedVcdFile() {}
    virtual bool open(const std::string& name) VL_MT_UNSAFE;
    virtual void close() VL_MT_UNSAFE;
@@ -62,23 +61,23 @@ private:

    VerilatedVcdFile* m_filep;  ///< File we're writing to
    bool m_fileNewed;  ///< m_filep needs destruction
-    bool m_isOpen;  ///< True indicates open file
-    bool m_evcd;  ///< True for evcd format
+    bool m_isOpen = false;  ///< True indicates open file
+    bool m_evcd = false;  ///< True for evcd format
    std::string m_filename;  ///< Filename we're writing to (if open)
-    vluint64_t m_rolloverMB;  ///< MB of file size to rollover at
-    int m_modDepth;  ///< Depth of module hierarchy
+    vluint64_t m_rolloverMB = 0;  ///< MB of file size to rollover at
+    int m_modDepth = 0;  ///< Depth of module hierarchy

    char* m_wrBufp;  ///< Output buffer
    char* m_wrFlushp;  ///< Output buffer flush trigger location
    char* m_writep;  ///< Write pointer into output buffer
    vluint64_t m_wrChunkSize;  ///< Output buffer size
-    vluint64_t m_wroteBytes;  ///< Number of bytes written to this file
+    vluint64_t m_wroteBytes = 0;  ///< Number of bytes written to this file

    std::vector<char> m_suffixes;  ///< VCD line end string codes + metadata
    const char* m_suffixesp;  ///< Pointer to first element of above

    typedef std::map<std::string, std::string> NameMap;
-    NameMap* m_namemapp;  ///< List of names for the header
+    NameMap* m_namemapp = nullptr;  ///< List of names for the header

    void bufferResize(vluint64_t minsize);
    void bufferFlush() VL_MT_UNSAFE_ONE;
@@ -101,13 +100,10 @@ private:

    void dumpHeader();

-    char* writeCode(char* writep, vluint32_t code);
+    static char* writeCode(char* writep, vluint32_t code);

    void finishLine(vluint32_t code, char* writep);

-    /// Flush any remaining data from all files
-    static void flush_all() VL_MT_UNSAFE_ONE;
-
    // CONSTRUCTORS
    VL_UNCOPYABLE(VerilatedVcd);

@@ -116,11 +112,11 @@ protected:
    // Implementation of VerilatedTrace interface

    // Implementations of protected virtual methods for VerilatedTrace
-    void emitTimeChange(vluint64_t timeui) VL_OVERRIDE;
+    virtual void emitTimeChange(vluint64_t timeui) override;

    // Hooks called from VerilatedTrace
-    bool preFullDump() VL_OVERRIDE { return isOpen(); }
-    bool preChangeDump() VL_OVERRIDE;
+    virtual bool preFullDump() override { return isOpen(); }
+    virtual bool preChangeDump() override;

    // Implementations of duck-typed methods for VerilatedTrace. These are
    // called from only one place (namely full*) so always inline them.
@@ -130,14 +126,13 @@ protected:
    inline void emitIData(vluint32_t code, IData newval, int bits);
    inline void emitQData(vluint32_t code, QData newval, int bits);
    inline void emitWData(vluint32_t code, const WData* newvalp, int bits);
-    inline void emitFloat(vluint32_t code, float newval);
    inline void emitDouble(vluint32_t code, double newval);

 public:
    //=========================================================================
    // External interface to client code

-    explicit VerilatedVcd(VerilatedVcdFile* filep = NULL);
+    explicit VerilatedVcd(VerilatedVcdFile* filep = nullptr);
    ~VerilatedVcd();

    // ACCESSORS
@@ -163,7 +158,6 @@ public:
    void declBus(vluint32_t code, const char* name, bool array, int arraynum, int msb, int lsb);
    void declQuad(vluint32_t code, const char* name, bool array, int arraynum, int msb, int lsb);
    void declArray(vluint32_t code, const char* name, bool array, int arraynum, int msb, int lsb);
-    void declFloat(vluint32_t code, const char* name, bool array, int arraynum);
    void declDouble(vluint32_t code, const char* name, bool array, int arraynum);

 #ifdef VL_TRACE_VCD_OLD_API
@@ -195,7 +189,6 @@ public:
    void fullWData(vluint32_t* oldp, const WData* newvalp, int bits) {
        fullArray(oldp - this->oldp(0), newvalp, bits);
    }
-    void fullFloat(vluint32_t* oldp, float newval) { fullFloat(oldp - this->oldp(0), newval); }
    void fullDouble(vluint32_t* oldp, double newval) { fullDouble(oldp - this->oldp(0), newval); }

    inline void chgBit(vluint32_t* oldp, CData newval) { chgBit(oldp - this->oldp(0), newval); }
@@ -214,9 +207,6 @@ public:
    inline void chgWData(vluint32_t* oldp, const WData* newvalp, int bits) {
        chgArray(oldp - this->oldp(0), newvalp, bits);
    }
-    inline void chgFloat(vluint32_t* oldp, float newval) {
-        chgFloat(oldp - this->oldp(0), newval);
-    }
    inline void chgDouble(vluint32_t* oldp, double newval) {
        chgDouble(oldp - this->oldp(0), newval);
    }
@@ -230,20 +220,10 @@ public:
    void fullArray(vluint32_t code, const vluint64_t* newvalp, int bits);
    void fullTriBit(vluint32_t code, const vluint32_t newval, const vluint32_t newtri);
    void fullTriBus(vluint32_t code, const vluint32_t newval, const vluint32_t newtri, int bits);
-    void fullTriQuad(vluint32_t code, const vluint64_t newval, const vluint32_t newtri, int bits);
+    void fullTriQuad(vluint32_t code, const vluint64_t newval, const vluint64_t newtri, int bits);
    void fullTriArray(vluint32_t code, const vluint32_t* newvalp, const vluint32_t* newtrip,
                      int bits);
    void fullDouble(vluint32_t code, const double newval);
-    void fullFloat(vluint32_t code, const float newval);
-
-    /// Inside dumping routines, dump one signal as unknowns
-    /// Presently this code doesn't change the oldval vector.
-    /// Thus this is for special standalone applications that after calling
-    /// fullBitX, must when then value goes non-X call fullBit.
-    void fullBitX(vluint32_t code);
-    void fullBusX(vluint32_t code, int bits);
-    void fullQuadX(vluint32_t code, int bits);
-    void fullArrayX(vluint32_t code, int bits);

    /// Inside dumping routines, dump one signal if it has changed.
    /// We do want to inline these to avoid calls when the value did not change.
@@ -262,7 +242,7 @@ public:
    inline void chgQuad(vluint32_t code, const vluint64_t newval, int bits) {
        vluint64_t diff = (*(reinterpret_cast<vluint64_t*>(oldp(code)))) ^ newval;
        if (VL_UNLIKELY(diff)) {
-            if (VL_UNLIKELY(bits == 64 || (diff & ((VL_ULL(1) << bits) - 1)))) {
+            if (VL_UNLIKELY(bits == 64 || (diff & ((1ULL << bits) - 1)))) {
                fullQuad(code, newval, bits);
            }
        }
@@ -303,12 +283,12 @@ public:
            }
        }
    }
-    inline void chgTriQuad(vluint32_t code, const vluint64_t newval, const vluint32_t newtri,
+    inline void chgTriQuad(vluint32_t code, const vluint64_t newval, const vluint64_t newtri,
                           int bits) {
        vluint64_t diff = (((*(reinterpret_cast<vluint64_t*>(oldp(code)))) ^ newval)
                           | ((*(reinterpret_cast<vluint64_t*>(oldp(code + 1)))) ^ newtri));
        if (VL_UNLIKELY(diff)) {
-            if (VL_UNLIKELY(bits == 64 || (diff & ((VL_ULL(1) << bits) - 1)))) {
+            if (VL_UNLIKELY(bits == 64 || (diff & ((1ULL << bits) - 1)))) {
                fullTriQuad(code, newval, newtri, bits);
            }
        }
@@ -329,15 +309,9 @@ public:
            fullDouble(code, newval);
        }
    }
-    inline void chgFloat(vluint32_t code, const float newval) {
-        // cppcheck-suppress invalidPointerCast
-        if (VL_UNLIKELY((*(reinterpret_cast<float*>(oldp(code)))) != newval)) {
-            fullFloat(code, newval);
-        }
-    }

-protected:
    // METHODS
+    // Old/standalone API only
    void evcd(bool flag) { m_evcd = flag; }
 #endif  // VL_TRACE_VCD_OLD_API
 };
@@ -362,8 +336,8 @@ class VerilatedVcdC {
    VL_UNCOPYABLE(VerilatedVcdC);

 public:
-    explicit VerilatedVcdC(VerilatedVcdFile* filep = NULL)
-        : m_sptrace(filep) {}
+    explicit VerilatedVcdC(VerilatedVcdFile* filep = nullptr)
+        : m_sptrace{filep} {}
    ~VerilatedVcdC() { close(); }
    /// Routines can only be called from one thread; allow next call from different thread
    void changeThread() { spTrace()->changeThread(); }
@@ -405,6 +379,15 @@ public:

    /// Internal class access
    inline VerilatedVcd* spTrace() { return &m_sptrace; }
+
+#ifdef VL_TRACE_VCD_OLD_API
+    //=========================================================================
+    // Note: These are only for testing for backward compatibility with foreign
+    // code and is not used by Verilator. Do not use these as there is no
+    // guarantee of functionality.
+    /// Use evcd format
+    void evcd(bool flag) VL_MT_UNSAFE_ONE { m_sptrace.evcd(flag); }
+#endif
 };

 #endif  // guard
@@ -25,22 +25,21 @@
 //======================================================================

 //--------------------------------------------------
-#if (SYSTEMC_VERSION >= 20050714)
 // SystemC 2.1.v1
 // cppcheck-suppress unusedFunction
 void VerilatedVcdSc::write_comment(const std::string&) {}
 void VerilatedVcdSc::trace(const unsigned int&, const std::string&, const char**) {}

-// clang-format off
-# define DECL_TRACE_METHOD_A(tp) \
+#define DECL_TRACE_METHOD_A(tp) \
    void VerilatedVcdSc::trace(const tp& object, const std::string& name) {}
-# define DECL_TRACE_METHOD_B(tp) \
+#define DECL_TRACE_METHOD_B(tp) \
    void VerilatedVcdSc::trace(const tp& object, const std::string& name, int width) {}

-# if (SYSTEMC_VERSION >= 20171012)
+// clang-format off
+#if (SYSTEMC_VERSION >= 20171012)
    DECL_TRACE_METHOD_A( sc_event )
    DECL_TRACE_METHOD_A( sc_time )
-# endif
+#endif

    DECL_TRACE_METHOD_A( bool )
    DECL_TRACE_METHOD_A( sc_dt::sc_bit )
@@ -50,9 +49,9 @@ void VerilatedVcdSc::trace(const unsigned int&, const std::string&, const char**
    DECL_TRACE_METHOD_B( unsigned short )
    DECL_TRACE_METHOD_B( unsigned int )
    DECL_TRACE_METHOD_B( unsigned long )
-# ifdef SYSTEMC_64BIT_PATCHES
+#ifdef SYSTEMC_64BIT_PATCHES
    DECL_TRACE_METHOD_B( unsigned long long)
-# endif
+#endif
    DECL_TRACE_METHOD_B( char )
    DECL_TRACE_METHOD_B( short )
    DECL_TRACE_METHOD_B( int )
@@ -76,92 +75,6 @@ void VerilatedVcdSc::trace(const unsigned int&, const std::string&, const char**
    DECL_TRACE_METHOD_A( sc_dt::sc_lv_base )
 // clang-format on

-//--------------------------------------------------
-#elif (SYSTEMC_VERSION > 20011000)
-// SystemC 2.0.1
-// cppcheck-suppress unusedFunction
-void VerilatedVcdSc::write_comment(const sc_string&) {}
-void VerilatedVcdSc::trace(const unsigned int&, const sc_string&, const char**) {}
-
-#define DECL_TRACE_METHOD_A(tp) \
-    void VerilatedVcdSc::trace(const tp& object, const sc_string& name) {}
-#define DECL_TRACE_METHOD_B(tp) \
-    void VerilatedVcdSc::trace(const tp& object, const sc_string& name, int width) {}
-
-// clang-format off
-    DECL_TRACE_METHOD_A( bool )
-    DECL_TRACE_METHOD_A( sc_bit )
-    DECL_TRACE_METHOD_A( sc_logic )
-    DECL_TRACE_METHOD_B( unsigned char )
-    DECL_TRACE_METHOD_B( unsigned short )
-    DECL_TRACE_METHOD_B( unsigned int )
-    DECL_TRACE_METHOD_B( unsigned long )
-#ifdef SYSTEMC_64BIT_PATCHES
-    DECL_TRACE_METHOD_B( unsigned long long)
-#endif
-#if (SYSTEMC_VERSION > 20041000)
-    DECL_TRACE_METHOD_B( unsigned long long)
-    DECL_TRACE_METHOD_B( long long)
-#endif
-    DECL_TRACE_METHOD_B( char )
-    DECL_TRACE_METHOD_B( short )
-    DECL_TRACE_METHOD_B( int )
-    DECL_TRACE_METHOD_B( long )
-    DECL_TRACE_METHOD_A( float )
-    DECL_TRACE_METHOD_A( double )
-    DECL_TRACE_METHOD_A( sc_int_base )
-    DECL_TRACE_METHOD_A( sc_uint_base )
-    DECL_TRACE_METHOD_A( sc_signed )
-    DECL_TRACE_METHOD_A( sc_unsigned )
-    DECL_TRACE_METHOD_A( sc_fxval )
-    DECL_TRACE_METHOD_A( sc_fxval_fast )
-    DECL_TRACE_METHOD_A( sc_fxnum )
-    DECL_TRACE_METHOD_A( sc_fxnum_fast )
-    DECL_TRACE_METHOD_A( sc_bv_base )
-    DECL_TRACE_METHOD_A( sc_lv_base )
-// clang-format on
-
-//--------------------------------------------------
-#else
-// SystemC 1.2.1beta
-// cppcheck-suppress unusedFunction
-void VerilatedVcdSc::write_comment(const sc_string&) {}
-void VerilatedVcdSc::trace(const unsigned int&, const sc_string&, const char**) {}
-
-#define DECL_TRACE_METHOD_A(tp) \
-    void VerilatedVcdSc::trace(const tp& object, const sc_string& name) {}
-#define DECL_TRACE_METHOD_B(tp) \
-    void VerilatedVcdSc::trace(const tp& object, const sc_string& name, int width) {}
-
-// clang-format off
-    DECL_TRACE_METHOD_A( bool )
-    DECL_TRACE_METHOD_B( unsigned char )
-    DECL_TRACE_METHOD_B( short unsigned int )
-    DECL_TRACE_METHOD_B( unsigned int )
-    DECL_TRACE_METHOD_B( long unsigned int )
-    DECL_TRACE_METHOD_B( char )
-    DECL_TRACE_METHOD_B( short int )
-    DECL_TRACE_METHOD_B( int )
-    DECL_TRACE_METHOD_B( long int )
-    DECL_TRACE_METHOD_A( float )
-    DECL_TRACE_METHOD_A( double )
-    DECL_TRACE_METHOD_A( sc_bit )
-    DECL_TRACE_METHOD_A( sc_logic )
-    DECL_TRACE_METHOD_A( sc_bool_vector )
-    DECL_TRACE_METHOD_A( sc_logic_vector )
-    DECL_TRACE_METHOD_A( sc_signal_bool_vector )
-    DECL_TRACE_METHOD_A( sc_signal_logic_vector )
-    DECL_TRACE_METHOD_A( sc_uint_base )
-    DECL_TRACE_METHOD_A( sc_int_base )
-    DECL_TRACE_METHOD_A( sc_unsigned )
-    DECL_TRACE_METHOD_A( sc_signed )
-    DECL_TRACE_METHOD_A( sc_signal_resolved )
-    DECL_TRACE_METHOD_A( sc_signal_resolved_vector )
-    DECL_TRACE_METHOD_A( sc_bv_ns::sc_bv_base )
-    DECL_TRACE_METHOD_A( sc_bv_ns::sc_lv_base )
-// clang-format on
-#endif
-
 #undef DECL_TRACE_METHOD_A
 #undef DECL_TRACE_METHOD_B

@@ -38,7 +38,6 @@ class VerilatedVcdSc : sc_trace_file, public VerilatedVcdC {
 public:
    VerilatedVcdSc() {
        sc_get_curr_simcontext()->add_trace_file(this);
-#if (SYSTEMC_VERSION >= 20060505)
        // We want to avoid a depreciated warning, but still be back compatible.
        // Turning off the message just for this still results in an
        // annoying "to turn off" message.
@@ -48,25 +47,13 @@ public:
            spTrace()->set_time_unit(tunits.to_string());
        }
        spTrace()->set_time_resolution(sc_get_time_resolution().to_string());
-#elif (SYSTEMC_VERSION > 20011000)
-        // To confuse matters 2.1.beta returns a char* here, while 2.1.v1 returns a std::string
-        // we allow both flavors with overloaded set_time_* functions.
-        spTrace()->set_time_unit(sc_get_default_time_unit().to_string());
-        spTrace()->set_time_resolution(sc_get_time_resolution().to_string());
-#endif
    }
    virtual ~VerilatedVcdSc() { close(); }

    // METHODS
    /// Called by SystemC simulate()
    virtual void cycle(bool delta_cycle) {
-#if (SYSTEMC_VERSION > 20011000)
        if (!delta_cycle) { this->dump(sc_time_stamp().to_double()); }
-#else
-        // VCD files must have integer timestamps, so we write all times in
-        // increments of time_resolution
-        if (!delta_cycle) { this->dump(sc_time_stamp().to_double()); }
-#endif
    }

 private:
@@ -76,26 +63,23 @@ private:
    // Cadence Incisive has these as abstract functions so we must create them
    virtual void set_time_unit(int exponent10_seconds) {}  // deprecated
 #endif
-#if defined(NC_SYSTEMC) || (SYSTEMC_VERSION >= 20111100)
-    virtual void set_time_unit(double v, sc_time_unit tu) {}
-#endif
+    virtual void set_time_unit(double v, sc_time_unit tu) {}  // LCOV_EXCL_LINE

 //--------------------------------------------------
-#if (SYSTEMC_VERSION >= 20050714)
-    // SystemC 2.1.v1
-    // clang-format off
-# define DECL_TRACE_METHOD_A(tp) virtual void trace(const tp& object, const std::string& name);
-# define DECL_TRACE_METHOD_B(tp) \
+// SystemC 2.1.v1
+#define DECL_TRACE_METHOD_A(tp) virtual void trace(const tp& object, const std::string& name);
+#define DECL_TRACE_METHOD_B(tp) \
    virtual void trace(const tp& object, const std::string& name, int width);

    virtual void write_comment(const std::string&);
    virtual void trace(const unsigned int&, const std::string&, const char**);

+    // clang-format off
    // Formatting matches that of sc_trace.h
-# if (SYSTEMC_VERSION >= 20171012)
+#if (SYSTEMC_VERSION >= 20171012)
    DECL_TRACE_METHOD_A( sc_event )
    DECL_TRACE_METHOD_A( sc_time )
-# endif
+#endif

    DECL_TRACE_METHOD_A( bool )
    DECL_TRACE_METHOD_A( sc_dt::sc_bit )
@@ -105,9 +89,9 @@ private:
    DECL_TRACE_METHOD_B( unsigned short )
    DECL_TRACE_METHOD_B( unsigned int )
    DECL_TRACE_METHOD_B( unsigned long )
-# ifdef SYSTEMC_64BIT_PATCHES
+#ifdef SYSTEMC_64BIT_PATCHES
    DECL_TRACE_METHOD_B( unsigned long long)
-# endif
+#endif
    DECL_TRACE_METHOD_B( char )
    DECL_TRACE_METHOD_B( short )
    DECL_TRACE_METHOD_B( int )
@@ -131,90 +115,6 @@ private:
    DECL_TRACE_METHOD_A( sc_dt::sc_lv_base )
    // clang-format on

-//--------------------------------------------------
-#elif (SYSTEMC_VERSION > 20011000)
-    // SystemC 2.0.1
-    // clang-format off
-# define DECL_TRACE_METHOD_A(tp) virtual void trace(const tp& object, const sc_string& name);
-# define DECL_TRACE_METHOD_B(tp) \
-    virtual void trace(const tp& object, const sc_string& name, int width);
-
-    virtual void write_comment(const sc_string&);
-    virtual void trace(const unsigned int&, const sc_string&, const char**);
-    virtual void delta_cycles(bool) {}
-    virtual void space(int n) {}
-
-    DECL_TRACE_METHOD_A( bool )
-    DECL_TRACE_METHOD_A( sc_bit )
-    DECL_TRACE_METHOD_A( sc_logic )
-    DECL_TRACE_METHOD_B( unsigned char )
-    DECL_TRACE_METHOD_B( unsigned short )
-    DECL_TRACE_METHOD_B( unsigned int )
-    DECL_TRACE_METHOD_B( unsigned long )
-# ifdef SYSTEMC_64BIT_PATCHES
-    DECL_TRACE_METHOD_B( unsigned long long)
-# endif
-# if (SYSTEMC_VERSION > 20041000)
-    DECL_TRACE_METHOD_B( unsigned long long)
-    DECL_TRACE_METHOD_B( long long)
-# endif
-    DECL_TRACE_METHOD_B( char )
-    DECL_TRACE_METHOD_B( short )
-    DECL_TRACE_METHOD_B( int )
-    DECL_TRACE_METHOD_B( long )
-    DECL_TRACE_METHOD_A( float )
-    DECL_TRACE_METHOD_A( double )
-    DECL_TRACE_METHOD_A( sc_int_base )
-    DECL_TRACE_METHOD_A( sc_uint_base )
-    DECL_TRACE_METHOD_A( sc_signed )
-    DECL_TRACE_METHOD_A( sc_unsigned )
-    DECL_TRACE_METHOD_A( sc_fxval )
-    DECL_TRACE_METHOD_A( sc_fxval_fast )
-    DECL_TRACE_METHOD_A( sc_fxnum )
-    DECL_TRACE_METHOD_A( sc_fxnum_fast )
-    DECL_TRACE_METHOD_A( sc_bv_base )
-    DECL_TRACE_METHOD_A( sc_lv_base )
-    // clang-format on
-
-//--------------------------------------------------
-#else
-    // SystemC 1.2.1beta
-    // clang-format off
-# define DECL_TRACE_METHOD_A(tp) virtual void trace(const tp& object, const sc_string& name);
-# define DECL_TRACE_METHOD_B(tp) \
-    virtual void trace(const tp& object, const sc_string& name, int width);
-
-    virtual void write_comment(const sc_string&);
-    virtual void trace(const unsigned int&, const sc_string&, const char**);
-
-    DECL_TRACE_METHOD_A( bool )
-    DECL_TRACE_METHOD_B( unsigned char )
-    DECL_TRACE_METHOD_B( short unsigned int )
-    DECL_TRACE_METHOD_B( unsigned int )
-    DECL_TRACE_METHOD_B( long unsigned int )
-    DECL_TRACE_METHOD_B( char )
-    DECL_TRACE_METHOD_B( short int )
-    DECL_TRACE_METHOD_B( int )
-    DECL_TRACE_METHOD_B( long int )
-    DECL_TRACE_METHOD_A( float )
-    DECL_TRACE_METHOD_A( double )
-    DECL_TRACE_METHOD_A( sc_bit )
-    DECL_TRACE_METHOD_A( sc_logic )
-    DECL_TRACE_METHOD_A( sc_bool_vector )
-    DECL_TRACE_METHOD_A( sc_logic_vector )
-    DECL_TRACE_METHOD_A( sc_signal_bool_vector )
-    DECL_TRACE_METHOD_A( sc_signal_logic_vector )
-    DECL_TRACE_METHOD_A( sc_uint_base )
-    DECL_TRACE_METHOD_A( sc_int_base )
-    DECL_TRACE_METHOD_A( sc_unsigned )
-    DECL_TRACE_METHOD_A( sc_signed )
-    DECL_TRACE_METHOD_A( sc_signal_resolved )
-    DECL_TRACE_METHOD_A( sc_signal_resolved_vector )
-    DECL_TRACE_METHOD_A( sc_bv_ns::sc_bv_base )
-    DECL_TRACE_METHOD_A( sc_bv_ns::sc_lv_base )
-# endif
-    // clang-format on
-
 #undef DECL_TRACE_METHOD_A
 #undef DECL_TRACE_METHOD_B
 };
@@ -122,7 +122,7 @@
 # if defined(_MSC_VER) && _MSC_VER >= 1900
 #  define VL_THREAD_LOCAL thread_local
 # elif defined(__GNUC__)
-#  if (__cplusplus < 201103L) && !defined(VL_THREADED_NO_C11_WARNING)
+#  if (__cplusplus < 201103L)
 #   error "VL_THREADED/--threads support requires C++-11 or newer only; use newer compiler"
 #  endif
 # else
@@ -144,30 +144,23 @@
 #define VL_MT_UNSAFE_ONE  ///< Comment tag that function is not threadsafe when VL_THREADED,
                          ///< protected to make sure single-caller

-#ifdef _MSC_VER
-# define VL_ULL(c) (c##ULL)  ///< Add appropriate suffix to 64-bit constant
-// Was "(c##ui64)". C++11 has standardized on ULL, and MSVC now supports this.
-// We propose to no longer require using this macro no sooner than June 2020.
-// File an issue ASAP if this breaks anything.
-#else
-# define VL_ULL(c) (c##ULL)  ///< Add appropriate suffix to 64-bit constant
-#endif
+#define VL_ULL(c) (c##ULL)  ///< Add appropriate suffix to 64-bit constant (deprecated)

 // This is not necessarily the same as #UL, depending on what the IData typedef is.
 #define VL_UL(c) (static_cast<IData>(c##UL))  ///< Add appropriate suffix to 32-bit constant

-#if defined(VL_CPPCHECK) || defined(__clang_analyzer__)
+#if defined(VL_CPPCHECK) || defined(__clang_analyzer__) || __cplusplus < 201103L
 # define VL_DANGLING(var)
 #else
-///< After e.g. delete, set variable to NULL to indicate must not use later
+/// After e.g. delete, set variable to nullptr to indicate must not use later
 # define VL_DANGLING(var) \
    do { \
-        (var) = NULL; \
+        *const_cast<const void**>(reinterpret_cast<const void* const*>(&var)) = nullptr; \
    } while (false)
 #endif

-///< Perform an e.g. delete, then set variable to NULL to indicate must not use later.
-///< Unlike VL_DO_CLEAR the setting of the variable is only for debug reasons.
+/// Perform an e.g. delete, then set variable to nullptr to indicate must not use later.
+/// Unlike VL_DO_CLEAR the setting of the variable is only for debug reasons.
 #define VL_DO_DANGLING(stmt, var) \
    do { \
        do { \
@@ -176,7 +169,7 @@
        VL_DANGLING(var); \
    } while (false)

-///< Perform an e.g. delete, then set variable to NULL as a requirement
+/// Perform an e.g. delete, then set variable to nullptr as a requirement
 #define VL_DO_CLEAR(stmt, stmt2) \
    do { \
        do { \
@@ -191,30 +184,18 @@
 // C++-2011

 #if __cplusplus >= 201103L || defined(__GXX_EXPERIMENTAL_CXX0X__) || defined(VL_CPPCHECK)
+// These are deprecated historical defines. We leave them in case users referenced them.
 # define VL_EQ_DELETE = delete
 # define vl_unique_ptr std::unique_ptr
-// By default we use std:: types in C++11.
-// Define VL_USE_UNORDERED_TYPES to test these pre-C++11 classes
-# ifdef VL_USE_UNORDERED_TYPES
-#  define VL_INCLUDE_UNORDERED_MAP "verilated_unordered_set_map.h"
-#  define VL_INCLUDE_UNORDERED_SET "verilated_unordered_set_map.h"
-# else
-#  define vl_unordered_map std::unordered_map
-#  define vl_unordered_set std::unordered_set
-#  define VL_INCLUDE_UNORDERED_MAP <unordered_map>
-#  define VL_INCLUDE_UNORDERED_SET <unordered_set>
-# endif
+# define vl_unordered_map std::unordered_map
+# define vl_unordered_set std::unordered_set
+# define VL_INCLUDE_UNORDERED_MAP <unordered_map>
+# define VL_INCLUDE_UNORDERED_SET <unordered_set>
 # define VL_FINAL final
 # define VL_MUTABLE mutable
 # define VL_OVERRIDE override
 #else
-# define VL_EQ_DELETE
-# define vl_unique_ptr std::auto_ptr
-# define VL_INCLUDE_UNORDERED_MAP "verilated_unordered_set_map.h"
-# define VL_INCLUDE_UNORDERED_SET "verilated_unordered_set_map.h"
-# define VL_FINAL
-# define VL_MUTABLE
-# define VL_OVERRIDE
+# error "Verilator requires a C++11 or newer compiler"
 #endif

 //=========================================================================
@@ -224,6 +205,20 @@
 # define VL_INLINE_OPT  ///< "inline" if compiling all objects in single compiler run
 #endif

+//=========================================================================
+// Internal coverage
+
+#ifdef VL_GCOV
+extern "C" {
+void __gcov_flush();  // gcc sources gcc/gcov-io.h has the prototype
+}
+/// Flush internal code coverage data before e.g. abort()
+# define VL_GCOV_FLUSH() \
+    __gcov_flush()
+#else
+# define VL_GCOV_FLUSH()
+#endif
+
 //=========================================================================
 // Warning disabled

@@ -381,8 +376,8 @@ typedef unsigned long long vluint64_t;  ///< 64-bit unsigned type

 // Used to declare a class as uncopyable; put after a private:
 #define VL_UNCOPYABLE(Type) \
-    Type(const Type& other) VL_EQ_DELETE; \
-    Type& operator=(const Type&) VL_EQ_DELETE
+    Type(const Type& other) = delete; \
+    Type& operator=(const Type&) = delete

 //=========================================================================
 // Verilated function size macros
@@ -401,7 +396,7 @@ typedef unsigned long long vluint64_t;  ///< 64-bit unsigned type
 #define VL_MASK_I(nbits) (((nbits) & VL_SIZEBITS_I) ? ((1U << ((nbits) & VL_SIZEBITS_I)) - 1) : ~0)
 /// Mask for quads with 1's where relevant bits are (0=all bits)
 #define VL_MASK_Q(nbits) \
-    (((nbits) & VL_SIZEBITS_Q) ? ((VL_ULL(1) << ((nbits) & VL_SIZEBITS_Q)) - VL_ULL(1)) : VL_ULL(~0))
+    (((nbits) & VL_SIZEBITS_Q) ? ((1ULL << ((nbits) & VL_SIZEBITS_Q)) - 1ULL) : ~0ULL)
 /// Mask for EData with 1's where relevant bits are (0=all bits)
 #define VL_MASK_E(nbits) VL_MASK_I(nbits)
 #define VL_EUL(n) VL_UL(n)  ///< Make constant number EData sized
@@ -428,7 +423,7 @@ typedef unsigned long long vluint64_t;  ///< 64-bit unsigned type
 // Performance counters

 /// The vluint64_t argument is loaded with a high-performance counter for profiling
-/// or 0x0 if not implemeted on this platform
+/// or 0x0 if not implemented on this platform
 #if defined(__i386__) || defined(__x86_64__)
 #define VL_RDTSC(val) \
    { \
@@ -493,6 +488,14 @@ typedef unsigned long long vluint64_t;  ///< 64-bit unsigned type
 #define VL_STRINGIFY(x) VL_STRINGIFY2(x)
 #define VL_STRINGIFY2(x) #x

+//=========================================================================
+// Conversions
+
+namespace vlstd {
+// C++17's std::as_const
+template <class T> T const& as_const(T& v) { return v; }
+};  // namespace vlstd
+
 //=========================================================================

 #endif  // Guard
@@ -1,58 +0,0 @@
-#!/usr/bin/env perl
-######################################################################
-#
-# Copyright 2007-2020 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.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
-#
-######################################################################
-
-# DESCRIPTION: Debugging of bison output
-
-use warnings;
-use strict;
-
-my $Debug;
-
-my %declared;
-my %used;
-
-my $body = 0;
-my $rule = "";
-my $lineno = 0;
-foreach my $line (<STDIN>) {
-    $lineno++;
-    chomp $line;
-    $line =~ s!//.*$!!g;
-    $line =~ s!\s+! !g;
-    next if $line eq '';
-    if ($line =~ m!^\%\%!) {
-        $body++;
-    } elsif ($body == 1) {
-        $rule .= $line;
-        if ($line =~ m!^\s*;\s*$!) {
-            #print "Rule: $rule\n";
-            ($rule =~ /^([a-zA-Z0-9_]+)(<\S+>)?:(.*)$/) or die "%Error: No rule name: $1\n";
-            my $rulename = $1; my $preaction = $3;
-            $declared{$rulename} = $lineno;
-            $preaction =~ s/\{[^\}]*\}/ /g;
-            #print "RULEN $rulename PA $preaction\n" if $Debug;
-            $rule = '';
-            foreach my $ref (split /\s+/, $preaction) {
-                next if $ref !~ /^[a-zA-Z]/;
-                next if $ref eq $rulename;
-                if (!$used{$ref} && $declared{$ref}) {
-                    print "   %Warning: $lineno: $ref used by $rulename after declaration\n";
-                }
-                $used{$ref} = $lineno;
-                print "  ref $ref\n" if $Debug;
-            }
-        }
-    }
-}
-
-# Local Variables:
-# compile-command: "./bisonreader < ../src/verilog.y"
-# End:
@@ -6,30 +6,71 @@ use warnings;
 use Cwd;
 use File::Copy qw(cp);
 use File::Path qw(mkpath);
+use File::Spec;
+use FindBin qw($RealBin);
 use Getopt::Long;
+use Parallel::Forker;
+use Unix::Processors;
 use IO::File;
 use Pod::Usage;
 use strict;
 use vars qw($Debug);

+our $Opt_Stop = 1;
+our $Opt_Fastcov = 1;
+our $Exclude_Branch_Regexp;
 our $Exclude_Line_Regexp;
+our $Remove_Gcda_Regexp;
+
 our @Remove_Sources;
 our @Source_Globs;

+our $Fork = new Parallel::Forker(use_sig_child => 1, poll_interval => 10*1000);
+$Fork->max_proc(Unix::Processors->new->max_online * 1.5);
+$SIG{CHLD} = sub { Parallel::Forker::sig_child($Fork); };
+$SIG{TERM} = sub { $Fork->kill_tree_all('TERM') if $Fork && $Fork->in_parent; die "Quitting...\n"; };
+
 #======================================================================
 # main

-our $Opt_Stage = 0;
+our $Opt_Hashset;
+our $opt_stages = '';
+our $Opt_Scenarios;
+our %Opt_Stages;
+our @Opt_Tests;

 autoflush STDOUT 1;
 autoflush STDERR 1;
 Getopt::Long::config("no_auto_abbrev");
 if (! GetOptions(
          "debug"       => sub { $Debug = 1; },
+          "hashset=s"   => \$Opt_Hashset,  # driver.pl hashset
          "<>"          => sub { die "%Error: Unknown parameter: $_[0]\n"; },
-          "stage=i"     => \$Opt_Stage,
+          "fastcov!"    => \$Opt_Fastcov,  # use fastcov, not documented, for debug
+          "scenarios=s" => \$Opt_Scenarios,  # driver.pl scenarios
+          "stage=s"     => \$opt_stages,  # starting stage number
+          "stages=s"    => \$opt_stages,  # starting stage number
+          "stop!"       => \$Opt_Stop,  # stop/do not stop on error in tests
+          "test=s@"     => \@Opt_Tests,  # test name
    )) {
-    die "%Error: Bad usage, try 'install_test --help'\n";
+    die "%Error: Bad usage, try 'code_coverage --help'\n";
+}
+
+{
+    my $start = 0;
+    my $end = 99;
+    if ($opt_stages && $opt_stages =~ /^(\d+)$/) {
+        $start = $end = $1;
+    } elsif ($opt_stages && $opt_stages =~ /^(\d+)-(\d+$)$/) {
+        $start = $1; $end = $2;
+    } elsif ($opt_stages && $opt_stages =~ /^-(\d+$)$/) {
+        $end = $1;
+    } elsif ($opt_stages && $opt_stages =~ /^(\d+)-$/) {
+        $start = $1;
+    } elsif ($opt_stages) {
+        die "%Error: --stages not understood: $opt_stages,";
+    }
+    for (my $n = $start; $n <= $end; ++$n) { $Opt_Stages{$n} = 1; }
 }

 test();
@@ -41,97 +82,238 @@ sub test {
    -r "nodist/code_coverage.dat" or die "%Error: Run from the top of the verilator kit,";
    require "./nodist/code_coverage.dat";

-    if ($Opt_Stage <= 0) {
-        print "Stage 0: configure (coverage on)\n";
-        run("make distclean");
-        run("./configure --enable-longtests CXX='g++ --coverage'");
-        run("make -k");
+    if ($Opt_Stages{1}) {
+        travis_fold_start("configure");
+        print "Stage 1: configure (coverage on)\n";
+        run("make distclean || true");
+        run("autoconf");
+        # Exceptions can pollute the branch coverage data
+        run("./configure --enable-longtests CXX='g++ --coverage -fno-exceptions -DVL_GCOV'");
+        travis_fold_end();
+    }
+
+    if ($Opt_Stages{2}) {
+        travis_fold_start("build");
+        print "Stage 2: build\n";
+        my $nproc = Unix::Processors->new->max_online;
+        run("make -k -j $nproc VERILATOR_NO_OPT_BUILD=1");
        # The optimized versions will not collect good coverage, overwrite them
        run("cp bin/verilator_bin_dbg bin/verilator_bin");
        run("cp bin/verilator_coverage_bin_dbg bin/verilator_coverage_bin");
+        travis_fold_end();
    }

-    if ($Opt_Stage <= 1) {
-        print "Stage 1: make examples (with coverage on)\n";
-        run("make examples");
-        run("make test_regress");
+    if ($Opt_Stages{3}) {
+        travis_fold_start("test");
+        print "Stage 3: make tests (with coverage on)\n";
+        if ($#Opt_Tests < 0) {
+            run("make examples VERILATOR_NO_OPT_BUILD=1")
+                if !$Opt_Scenarios || $Opt_Scenarios =~ /dist/i;
+            run("make test_regress VERILATOR_NO_OPT_BUILD=1"
+                . ($Opt_Scenarios ? " SCENARIOS='".$Opt_Scenarios."'" : "")
+                . ($Opt_Hashset ? " DRIVER_HASHSET='--hashset=".$Opt_Hashset."'" : "")
+                . ($Opt_Stop ? '' : ' || true'));
+        } else {
+            foreach my $test (@Opt_Tests) {
+                if (! -f $test && -f "test_regress/t/${test}") {
+                    $test = "test_regress/t/${test}";
+                }
+                run($test);
+            }
+        }
+        travis_fold_end();
    }

    my $cc_dir = "nodist/obj_dir/coverage";
-    if ($Opt_Stage <= 2) {
-        print "Stage 2: Create info files under $cc_dir\n";
+    if ($Opt_Stages{4}) {
+        travis_fold_start("gcno");
+        print "Stage 4: Create gcno files under $cc_dir\n";
        mkpath($cc_dir);
        mkpath("$cc_dir/info");
        my $dats = `find . -print | grep .gcda`;
+        my %dats;
+        foreach my $dat (split '\n', $dats) {
+            $dats{$dat} = 1;
+        }
+        foreach my $dat (sort keys %dats) {
+            (my $gcno = $dat) =~ s!\.gcda$!.gcno!;
+            if ($dat =~ /$Remove_Gcda_Regexp/) {
+                # Remove .gcda/.gcno for files we don't care about before we slowly
+                # read them
+                unlink $dat;
+                unlink $gcno;
+                delete $dats{$dat};
+                next;
+            }
+        }
+        $dats = `find . -print | grep .gcno`;
+        my %gcnos;
+        foreach my $gcno (split '\n', $dats) {
+            (my $gbase = $gcno) =~ s!.*/!!;
+            $gcnos{$gbase} = File::Spec->rel2abs($gcno);
+        }
+        # We need a matching .gcno for every .gcda, try to find a matching file elsewhere
+        foreach my $dat (sort keys %dats) {
+            (my $gcno = $dat) =~ s!\.gcda$!.gcno!;
+            (my $gbase = $gcno) =~ s!.*/!!;
+            if (!-r $gcno) {
+                if ($gcnos{$gbase}) {
+                    symlink($gcnos{$gbase}, $gcno)
+                        or die "%Error: can't ln -s $gcnos{$gbase} $gcno,";
+                } else {
+                    warn "MISSING .gcno for a .gcda: $gcno\n";
+                }
+            }
+        }
+        travis_fold_end();
+    }
+
+    if ($Opt_Stages{5} && $Opt_Fastcov) {
+        travis_fold_start("fastcov");
+        # Must run in root directory to find all files
+        mkpath($cc_dir);
+        #run("${RealBin}/fastcov.py -b -c src/obj_dbg -X".
+        #    " --exclude /usr --exclude test_regress"
+        #    ." -o ${cc_dir}/app_total.json");
+        run("${RealBin}/fastcov.py -b -c src/obj_dbg -X --lcov".
+            " --exclude /usr --exclude test_regress"
+            ." -o ${cc_dir}/app_total.info");
+        travis_fold_end();
+    }
+
+    if ($Opt_Stages{5} && !$Opt_Fastcov) {
+        travis_fold_start("infos");
+        print "Stage 5: make infos\n";
+        my $dats = `find . -print | grep .gcda`;
        my %dirs;
        foreach my $dat (split '\n', $dats) {
-            $dat =~ s!/[^/]+$!!;
-            $dirs{$dat} = 1;
+            (my $dir = $dat) =~ s!/[^/]+$!!;
+            $dirs{$dir} = 1;
        }
+
        foreach my $dir (sort keys %dirs) {
            (my $outname = $dir) =~ s![^a-zA-Z0-9]+!_!g;
-            run("cd $cc_dir/info ; lcov -c -d ../../../../$dir -o app_test_${outname}.info");
+            $Fork->schedule(run_on_start => sub {
+                # .info may be empty, so ignore errors (unfortunately)
+                run("cd $cc_dir/info ; lcov -c -d ../../../../$dir --exclude /usr -o app_test_${outname}.info || true");
+                            })->run;
        }
+        $Fork->wait_all;
+        travis_fold_end();
    }

-    if ($Opt_Stage <= 3) {
-        # lcov doesn't have a control file to override single lines, so replicate the sources
-        print "Stage 3: Clone sources under $cc_dir\n";
+    if ($Opt_Stages{6}) {
+        travis_fold_start("clone");
+        # No control file to override single lines, so replicate the sources
+        # Also lets us see the insertion markers in the HTML source res
+        print "Stage 6: Clone sources under $cc_dir\n";
        clone_sources($cc_dir);
+        travis_fold_end();
    }

-    if ($Opt_Stage <= 4) {
-        print "Stage 4: Copy .gcno files\n";
+    if ($Opt_Stages{8} && !$Opt_Fastcov) {
+        travis_fold_start("copy");
+        print "Stage 8: Copy .gcno files\n";
        my $dats = `find . -print | grep .gcno`;
-        foreach my $dat (split '\n', $dats) {
+        foreach my $dat (sort (split '\n', $dats)) {
            next if $dat =~ /$cc_dir/;
            my $outdat = $cc_dir."/".$dat;
            #print "cp $dat, $outdat);\n";
            cp($dat, $outdat);
        }
+        travis_fold_end();
    }

-    if ($Opt_Stage <= 5) {
-        print "Stage 5: Combine data files\n";
-        run("cd $cc_dir ; lcov -c -i -d src/obj_dbg -o app_base.info");
-        run("cd $cc_dir ; lcov -a app_base.info -o app_total.info");
-        my $infos = `cd $cc_dir ; find info -print | grep .info`;
-        my $comb = "";
-        my @infos = (split /\n/, $infos);
-        foreach my $info (@infos) {
-            $comb .= " -a $info";
-            # Need to batch them to avoid overrunning shell command length limit
-            if (length($comb) > 10000 || $info eq $infos[$#infos]) {
-                run("cd $cc_dir ; lcov -a app_total.info $comb -o app_total.info");
-                $comb = "";
+    if ($Opt_Stages{10} && !$Opt_Fastcov) {
+        travis_fold_start("combine");
+        print "Stage 10: Combine data files\n";
+        {
+            run("cd $cc_dir ; lcov -c -i -d src/obj_dbg -o app_base.info");
+            run("cd $cc_dir ; lcov -a app_base.info -o app_total.info");
+            my $infos = `cd $cc_dir ; find info -print | grep .info`;
+            my $comb = "";
+            my @infos = (sort (split /\n/, $infos));
+            foreach my $info (@infos) {
+                $comb .= " -a $info";
+                # Need to batch them to avoid overrunning shell command length limit
+                if (length($comb) > 10000 || $info eq $infos[$#infos]) {
+                    # .info may be empty, so ignore errors (unfortunately)
+                    run("cd $cc_dir ; lcov -a app_total.info $comb -o app_total.info || true");
+                    $comb = "";
+                }
            }
        }
+        travis_fold_end();
    }

-    if ($Opt_Stage <= 6) {
-        print "Stage 6: Filter processed source files\n";
-        my $cmd = '';
-        foreach my $glob (@Remove_Sources) {
-            $cmd .= " '$glob'";
+    if ($Opt_Stages{11}) {
+        travis_fold_start("dirs");
+        print "Stage 11: Cleanup paths\n";
+        if ($Opt_Fastcov) {
+            cleanup_abs_paths_info($cc_dir, "$cc_dir/app_total.info", "$cc_dir/app_total.info");
+            #cleanup_abs_paths_json($cc_dir, "$cc_dir/app_total.json", "$cc_dir/app_total.json");
+        } else {
+            cleanup_abs_paths_info($cc_dir, "$cc_dir/app_total.info", "$cc_dir/app_total.info");
        }
-        run("cd $cc_dir ; lcov --remove app_total.info $cmd -o app_total.info");
+        travis_fold_end();
    }

-    if ($Opt_Stage <= 7) {
-        print "Stage 7: Create HTML\n";
-        cleanup_abs_paths($cc_dir, "$cc_dir/app_total.info", "$cc_dir/app_total.info");
-        run("cd $cc_dir ; genhtml app_total.info --demangle-cpp"
+    if ($Opt_Stages{12}) {
+        travis_fold_start("filter");
+        print "Stage 12: Filter processed source files\n";
+        my $inc = '';
+        foreach my $glob (@Source_Globs) {
+            foreach my $infile (glob $glob) {
+                $inc .= " '$infile'";
+            }
+        }
+        my $exc = '';
+        foreach my $glob (@Remove_Sources) {
+            # Fastcov does exact match not globbing at present
+            # Lcov requires whole path match so needs the glob
+            $glob =~ s!^\*!! if $Opt_Fastcov;
+            $glob =~ s!\*$!! if $Opt_Fastcov;
+            $exc .= " '$glob'";
+        }
+        if ($Opt_Fastcov) {
+            $inc = "--include ".$inc if $inc ne '';
+            $exc = "--exclude ".$exc if $exc ne '';
+            run("cd $cc_dir ; ${RealBin}/fastcov.py -C app_total.info ${inc} ${exc} -x --lcov -o app_total_f.info");
+        } else {
+            run("cd $cc_dir ; lcov --remove app_total.info $exc -o app_total_f.info");
+        }
+        travis_fold_end();
+    }
+
+    if ($Opt_Stages{17}) {
+        travis_fold_start("report");
+        print "Stage 17: Create HTML\n";
+        run("cd $cc_dir ; genhtml app_total_f.info --demangle-cpp"
            ." --rc lcov_branch_coverage=1 --rc genhtml_hi_limit=100 --output-directory html");
+        travis_fold_end();
    }

-    if ($Opt_Stage <= 9) {
+    if ($Opt_Stages{18}) {
+        travis_fold_start("upload");
+        print "Stage 18: Upload\n";
+        my $cmd = "bash <(curl -s https://codecov.io/bash) -f $cc_dir/app_total.info";
+        print "print: Not running: export CODECOV_TOKEN=<hidden>\n";
+        print "print: Not running: $cmd\n";
+        travis_fold_end();
+    }
+
+    if ($Opt_Stages{19}) {
        print "*-* All Finished *-*\n";
+        print "\n";
+        print "* See report in ${cc_dir}/html/index.html\n";
+        print "* Remember to make distclean && ./configure before working on non-coverage\n";
    }
 }

 sub clone_sources {
    my $cc_dir = shift;
    my $excluded_lines = 0;
+    my $excluded_br_lines = 0;
    foreach my $glob (@Source_Globs) {
        foreach my $infile (glob $glob) {
            $infile !~ m!^/!
@@ -145,21 +327,35 @@ sub clone_sources {
            while (defined(my $line = $fh->getline)) {
                $lineno++;
                chomp $line;
-                if ($line !~ m!// LCOV_EXCL_LINE!
-                    && $line =~ /$Exclude_Line_Regexp/) {
-                    $line .= "  //code_coverage: // LCOV_EXCL_LINE";
+                if ($line =~ /LCOV_EXCL_LINE/) {
+                    $line .= " LCOV_EXCL_BR_LINE";
+                }
+                elsif ($line =~ /LCOV_EXCL_START/) {
+                    $line .= " LCOV_EXCL_BR_START";
+                }
+                elsif ($line =~ /LCOV_EXCL_STOP/) {
+                    $line .= " LCOV_EXCL_BR_STOP";
+                }
+                elsif ($line =~ /$Exclude_Line_Regexp/) {
+                    $line .= "  //code_coverage: // LCOV_EXCL_LINE LCOV_EXCL_BR_LINE";
                    $excluded_lines++;
+                    $excluded_br_lines++;
+                    #print "$infile:$lineno: $line";
+                }
+                elsif ($line =~ /$Exclude_Branch_Regexp/) {
+                    $line .= "  //code_coverage: // LCOV_EXCL_BR_LINE";
+                    $excluded_br_lines++;
                    #print "$infile:$lineno: $line";
-                } else {
                }
                $ofh->print("$line\n");
            }
        }
    }
-    print "Source code lines automatically LCOV_EXCL_LINE'ed: $excluded_lines\n";
+    print "Number of source lines automatically LCOV_EXCL_LINE'ed: $excluded_lines\n";
+    print "Number of source lines automatically LCOV_EXCL_BR_LINE'ed: $excluded_br_lines\n";
 }

-sub cleanup_abs_paths {
+sub cleanup_abs_paths_info {
    my $cc_dir = shift;
    my $infile = shift;
    my $outfile = shift;
@@ -178,18 +374,41 @@ sub cleanup_abs_paths {
    $ofh->print(@lines);
 }

+sub cleanup_abs_paths_json {
+    my $cc_dir = shift;
+    my $infile = shift;
+    my $outfile = shift;
+    # Handcrafted cleanup, alternative would be to deserialize/serialize JSON
+    # But JSON::Parse not installed by default
+    # JSON::PP more likely to be installed, but slower
+    my $fh = IO::File->new("<$infile") or die "%Error: $! $infile,";
+    my @lines;
+    while (defined(my $line = $fh->getline)) {
+        $line =~ s!"$ENV{VERILATOR_ROOT}/!"!g;
+        $line =~ s!"$cc_dir/!"!g;
+        $line =~ s!obj_dbg/verilog.y$!verilog.y!g;
+        push @lines, $line;
+    }
+    my $ofh = IO::File->new(">$outfile") or die "%Error: $! $outfile,";
+    $ofh->print(@lines);
+}
+
 #######################################################################
 # .dat file callbacks

+sub exclude_branch_regexp {
+    $Exclude_Branch_Regexp = shift;
+}
 sub exclude_line_regexp {
    $Exclude_Line_Regexp = shift;
 }
-
+sub remove_gcda_regexp {
+    $Remove_Gcda_Regexp = shift;
+}
 sub remove_source {
    my @srcs = @_;
    push @Remove_Sources, @srcs;
 }
-
 sub source_globs {
    my @dirs = @_;
    push @Source_Globs, @dirs;
@@ -206,6 +425,15 @@ sub run {
    ($status == 0) or die "%Error: Command Failed $command, $status, stopped";
 }

+our $_Travis_Action;
+sub travis_fold_start {
+    $_Travis_Action = shift;
+    print "travis_fold:start:$_Travis_Action\n";
+}
+sub travis_fold_end {
+    print "travis_fold:end:$_Travis_Action\n";
+}
+
 #######################################################################
 __END__

@@ -231,13 +459,30 @@ This will rebuild the current object files.

 =over 4

+=item --hashset I<hashset>
+
+Pass test hashset onto driver.pl test harness.
+
 =item --help

 Displays this message and program version and exits.

-=item -stage I<stage>
+=item --scenarios I<scenarios>

-Runs a specific stage (see the script).
+Pass test scenarios onto driver.pl test harness.
+
+=item --stages I<stage>
+
+Runs a specific stage or range of stages (see the script).
+
+=item --no-stop
+
+Do not stop collecting data if tests fail.
+
+=item --test I<test_regress_test_name>
+
+Instead of normal regressions, run the specified test.  May be specified
+multiple times for multiple tests.

 =back

@@ -21,7 +21,8 @@ source_globs("src/*.cpp",
             "include/*/*.c",
    );

-remove_source("/usr/include/*");
+# Note *'s are removed when using fastcov
+remove_source("/usr/*");
 remove_source("*/include/sysc/*");
 remove_source("*/V3ClkGater.cpp");
 remove_source("*/V3ClkGater.h");
@@ -37,7 +38,22 @@ remove_source("*include/gtkwave/*");
 remove_source("*test_regress/*");
 remove_source("*examples/*");

+# Remove collected coverage on each little test main file
+# Would just be removed with remove_source in later step
+remove_gcda_regexp(qr!test_regress/.*/(Vt_|Vtop_).*\.gcda!);

-exclude_line_regexp(qr/(\bv3fatalSrc\b|\bVL_UNCOVERABLE\b)/);
+# Exclude line entirely, also excludes from function and branch coverage
+exclude_line_regexp(qr/(\bv3fatalSrc\b
+                    |\bfatalSrc\b
+                    |\bVL_UNCOVERABLE\b
+                    |\bVL_FATAL
+                    |\bUASSERT
+                    |\bERROR_RSVD_WORD
+                    |\bV3ERROR_NA
+                    |\bUINFO\b)/x);
+
+# Exclude for branch coverage only
+exclude_branch_regexp(qr/(\bdebug\(\)
+                         |\bSELF_CHECK)/x);

 1;
@@ -0,0 +1,744 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: MIT
+# Copyright 2018-present, Bryan Gillespie
+"""
+    Author: Bryan Gillespie
+    https://github.com/RPGillespie6/fastcov
+
+    A massively parallel gcov wrapper for generating intermediate coverage formats fast
+
+    The goal of fastcov is to generate code coverage intermediate formats as fast as possible,
+    even for large projects with hundreds of gcda objects. The intermediate formats may then be
+    consumed by a report generator such as lcov's genhtml, or a dedicated frontend such as coveralls.
+
+    Sample Usage:
+        $ cd build_dir
+        $ ./fastcov.py --zerocounters
+        $ <run unit tests>
+        $ ./fastcov.py --exclude /usr/include test/ --lcov -o report.info
+        $ genhtml -o code_coverage report.info
+"""
+
+import re
+import os
+import sys
+import glob
+import json
+import time
+import logging
+import argparse
+import threading
+import subprocess
+import multiprocessing
+
+FASTCOV_VERSION = (1,7)
+MINIMUM_PYTHON  = (3,5)
+MINIMUM_GCOV    = (9,0,0)
+
+# Interesting metrics
+START_TIME    = time.monotonic()
+GCOVS_TOTAL   = 0
+GCOVS_SKIPPED = 0
+
+# For when things go wrong...
+# Start error codes at 3 because 1-2 are special
+# See https://stackoverflow.com/a/1535733/2516916
+EXIT_CODE  = 0
+EXIT_CODES = {
+    "gcov_version": 3,
+    "python_version": 4,
+    "unsupported_coverage_format": 5,
+    "excl_not_found": 6,
+}
+
+# Disable all logging in case developers are using this as a module
+logging.disable(level=logging.CRITICAL)
+
+class FastcovFormatter(logging.Formatter):
+    def format(self, record):
+        record.levelname = record.levelname.lower()
+        log_message = super(FastcovFormatter, self).format(record)
+        return "[{:.3f}s] {}".format(stopwatch(), log_message)
+
+def chunks(l, n):
+    """Yield successive n-sized chunks from l."""
+    for i in range(0, len(l), n):
+        yield l[i:i + n]
+
+def setExitCode(key):
+    global EXIT_CODE
+    EXIT_CODE = EXIT_CODES[key]
+
+def incrementCounters(total, skipped):
+    global GCOVS_TOTAL
+    global GCOVS_SKIPPED
+    GCOVS_TOTAL   += total
+    GCOVS_SKIPPED += skipped
+
+def stopwatch():
+    """Return number of seconds since last time this was called."""
+    global START_TIME
+    end_time   = time.monotonic()
+    delta      = end_time - START_TIME
+    START_TIME = end_time
+    return delta
+
+def parseVersionFromLine(version_str):
+    """Given a string containing a dotted integer version, parse out integers and return as tuple."""
+    version = re.search(r'(\d+\.\d+\.\d+)', version_str)
+
+    if not version:
+        return (0,0,0)
+
+    return tuple(map(int, version.group(1).split(".")))
+
+def getGcovVersion(gcov):
+    p = subprocess.Popen([gcov, "-v"], stdout=subprocess.PIPE)
+    output = p.communicate()[0].decode('UTF-8')
+    p.wait()
+    return parseVersionFromLine(output.split("\n")[0])
+
+def removeFiles(files):
+    for file in files:
+        os.remove(file)
+
+def getFilteredCoverageFiles(coverage_files, exclude):
+    def excludeGcda(gcda):
+        for ex in exclude:
+            if ex in gcda:
+                logging.debug("Omitting %s due to '--exclude-gcda %s'", gcda, ex)
+                return False
+        return True
+    return list(filter(excludeGcda, coverage_files))
+
+def findCoverageFiles(cwd, coverage_files, use_gcno):
+    coverage_type = "user provided"
+    if not coverage_files:
+        coverage_type = "gcno" if use_gcno else "gcda"
+        coverage_files = glob.glob(os.path.join(os.path.abspath(cwd), "**/*." + coverage_type), recursive=True)
+
+    logging.info("Found {} coverage files ({})".format(len(coverage_files), coverage_type))
+    logging.debug("Coverage files found:\n    %s", "\n    ".join(coverage_files))
+    return coverage_files
+
+def gcovWorker(data_q, metrics_q, args, chunk, gcov_filter_options):
+    base_report   = {"sources": {}}
+    gcovs_total   = 0
+    gcovs_skipped = 0
+
+    gcov_args = "-it"
+    if args.branchcoverage or args.xbranchcoverage:
+        gcov_args += "b"
+
+    p = subprocess.Popen([args.gcov, gcov_args] + chunk, cwd=args.cdirectory, stdout=subprocess.PIPE, stderr=subprocess.DEVNULL)
+    for line in iter(p.stdout.readline, b''):
+        intermediate_json = json.loads(line.decode(sys.stdout.encoding))
+        intermediate_json_files = processGcovs(args.cdirectory, intermediate_json["files"], gcov_filter_options)
+        for f in intermediate_json_files:
+            distillSource(f, base_report["sources"], args.test_name, args.xbranchcoverage)
+        gcovs_total   += len(intermediate_json["files"])
+        gcovs_skipped += len(intermediate_json["files"]) - len(intermediate_json_files)
+
+    p.wait()
+    data_q.put(base_report)
+    metrics_q.put((gcovs_total, gcovs_skipped))
+
+def processGcdas(args, coverage_files, gcov_filter_options):
+    chunk_size = max(args.minimum_chunk, int(len(coverage_files) / args.jobs) + 1)
+
+    processes = []
+    data_q    = multiprocessing.Queue()
+    metrics_q = multiprocessing.Queue()
+    for chunk in chunks(coverage_files, chunk_size):
+        p = multiprocessing.Process(target=gcovWorker, args=(data_q, metrics_q, args, chunk, gcov_filter_options))
+        processes.append(p)
+        p.start()
+
+    logging.info("Spawned {} gcov processes, each processing at most {} coverage files".format(len(processes), chunk_size))
+
+    fastcov_jsons = []
+    for p in processes:
+        fastcov_jsons.append(data_q.get())
+        incrementCounters(*metrics_q.get())
+
+    for p in processes:
+        p.join()
+
+    base_fastcov = fastcov_jsons.pop()
+    for fj in fastcov_jsons:
+        combineReports(base_fastcov, fj)
+
+    return base_fastcov
+
+def shouldFilterSource(source, gcov_filter_options):
+    """Returns true if the provided source file should be filtered due to CLI options, otherwise returns false."""
+    # If explicit sources were passed, check for match
+    if gcov_filter_options["sources"]:
+        if source not in gcov_filter_options["sources"]:
+            logging.debug("Filtering coverage for '%s' due to option '--source-files'", source)
+            return True
+
+    # Check exclude filter
+    for ex in gcov_filter_options["exclude"]:
+        if ex in source:
+            logging.debug("Filtering coverage for '%s' due to option '--exclude %s'", source, ex)
+            return True
+
+    # Check include filter
+    if gcov_filter_options["include"]:
+        included = False
+        for inc in gcov_filter_options["include"]:
+            if inc in source:
+                included = True
+                break
+
+        if not included:
+            logging.debug("Filtering coverage for '%s' due to option '--include %s'", source, " ".join(gcov_filter_options["include"]))
+            return True
+
+    return False
+
+def filterFastcov(fastcov_json, args):
+    logging.info("Performing filtering operations (if applicable)")
+    gcov_filter_options = getGcovFilterOptions(args)
+    for source in list(fastcov_json["sources"].keys()):
+        if shouldFilterSource(source, gcov_filter_options):
+            del fastcov_json["sources"][source]
+
+def processGcov(cwd, gcov, files, gcov_filter_options):
+    # Add absolute path
+    gcov["file_abs"] = os.path.abspath(os.path.join(cwd, gcov["file"]))
+
+    if shouldFilterSource(gcov["file_abs"], gcov_filter_options):
+        return
+
+    files.append(gcov)
+    logging.debug("Accepted coverage for '%s'", gcov["file_abs"])
+
+def processGcovs(cwd, gcov_files, gcov_filter_options):
+    files = []
+    for gcov in gcov_files:
+        processGcov(cwd, gcov, files, gcov_filter_options)
+    return files
+
+def dumpBranchCoverageToLcovInfo(f, branches):
+    branch_miss = 0
+    branch_found = 0
+    brda = []
+    for line_num, branch_counts in branches.items():
+        for i, count in enumerate(branch_counts):
+            # Branch (<line number>, <block number>, <branch number>, <taken>)
+            brda.append((line_num, int(i/2), i, count))
+            branch_miss += int(count == 0)
+            branch_found += 1
+    for v in sorted(brda):
+        f.write("BRDA:{},{},{},{}\n".format(*v))
+    f.write("BRF:{}\n".format(branch_found))                # Branches Found
+    f.write("BRH:{}\n".format(branch_found - branch_miss))  # Branches Hit
+
+def dumpToLcovInfo(fastcov_json, output):
+    with open(output, "w") as f:
+        sources = fastcov_json["sources"]
+        for sf in sorted(sources.keys()):
+            for tn in sorted(sources[sf].keys()):
+                data = sources[sf][tn]
+                f.write("TN:{}\n".format(tn)) #Test Name - used mainly in conjuction with genhtml --show-details
+                f.write("SF:{}\n".format(sf)) #Source File
+
+                fn_miss = 0
+                fn = []
+                fnda = []
+                for function, fdata in data["functions"].items():
+                    fn.append((fdata["start_line"], function))  # Function Start Line
+                    fnda.append((fdata["execution_count"], function))  # Function Hits
+                    fn_miss += int(fdata["execution_count"] == 0)
+                # NOTE: lcov sorts FN, but not FNDA.
+                for v in sorted(fn):
+                    f.write("FN:{},{}\n".format(*v))
+                for v in sorted(fnda):
+                    f.write("FNDA:{},{}\n".format(*v))
+                f.write("FNF:{}\n".format(len(data["functions"])))               #Functions Found
+                f.write("FNH:{}\n".format((len(data["functions"]) - fn_miss)))   #Functions Hit
+
+                if data["branches"]:
+                    dumpBranchCoverageToLcovInfo(f, data["branches"])
+
+                line_miss = 0
+                da = []
+                for line_num, count in data["lines"].items():
+                    da.append((line_num, count))
+                    line_miss += int(count == 0)
+                for v in sorted(da):
+                    f.write("DA:{},{}\n".format(*v))  # Line
+                f.write("LF:{}\n".format(len(data["lines"])))                 #Lines Found
+                f.write("LH:{}\n".format((len(data["lines"]) - line_miss)))   #Lines Hit
+                f.write("end_of_record\n")
+
+def getSourceLines(source, fallback_encodings=[]):
+    """Return a list of lines from the provided source, trying to decode with fallback encodings if the default fails."""
+    default_encoding = sys.getdefaultencoding()
+    for encoding in [default_encoding] + fallback_encodings:
+        try:
+            with open(source, encoding=encoding) as f:
+                return f.readlines()
+        except UnicodeDecodeError:
+            pass
+
+    logging.warning("Could not decode '{}' with {} or fallback encodings ({}); ignoring errors".format(source, default_encoding, ",".join(fallback_encodings)))
+    with open(source, errors="ignore") as f:
+        return f.readlines()
+
+def exclProcessSource(fastcov_sources, source, exclude_branches_sw, include_branches_sw, fallback_encodings):
+    start_line = 0
+    end_line = 0
+    # Start enumeration at line 1 because the first line of the file is line 1 not 0
+    for i, line in enumerate(getSourceLines(source, fallback_encodings), 1):
+        # Cycle through test names (likely only 1)
+        for test_name in fastcov_sources[source]:
+            fastcov_data = fastcov_sources[source][test_name]
+
+            # Build line to function dict so can quickly delete by line number
+            line_to_func = {}
+            for f in fastcov_data["functions"].keys():
+                l = fastcov_data["functions"][f]["start_line"]
+                if l not in line_to_func:
+                    line_to_func[l] = set()
+                line_to_func[l].add(f)
+
+            if i in fastcov_data["branches"]:
+                del_exclude_br = exclude_branches_sw and any(line.lstrip().startswith(e) for e in exclude_branches_sw)
+                del_include_br = include_branches_sw and all(not line.lstrip().startswith(e) for e in include_branches_sw)
+                if del_exclude_br or del_include_br:
+                    del fastcov_data["branches"][i]
+
+            if "LCOV_EXCL" not in line:
+                continue
+
+            if "LCOV_EXCL_LINE" in line:
+                for key in ["lines", "branches"]:
+                    if i in fastcov_data[key]:
+                        del fastcov_data[key][i]
+                if i in line_to_func:
+                    for key in line_to_func[i]:
+                        if key in fastcov_data["functions"]:
+                            del fastcov_data["functions"][key]
+            elif "LCOV_EXCL_START" in line:
+                start_line = i
+            elif "LCOV_EXCL_STOP" in line:
+                end_line = i
+
+                if not start_line:
+                    end_line = 0
+                    continue
+
+                for key in ["lines", "branches"]:
+                    for line_num in list(fastcov_data[key].keys()):
+                        if start_line <= line_num <= end_line:
+                            del fastcov_data[key][line_num]
+
+                for line_num in range(start_line, end_line):
+                    if line_num in line_to_func:
+                        for key in line_to_func[line_num]:
+                            if key in fastcov_data["functions"]:
+                                del fastcov_data["functions"][key]
+
+                start_line = end_line = 0
+            elif "LCOV_EXCL_BR_LINE" in line:
+                if i in fastcov_data["branches"]:
+                    del fastcov_data["branches"][i]
+
+def exclMarkerWorker(fastcov_sources, chunk, exclude_branches_sw, include_branches_sw, fallback_encodings):
+    for source in chunk:
+        try:
+            exclProcessSource(fastcov_sources, source, exclude_branches_sw, include_branches_sw, fallback_encodings)
+        except FileNotFoundError:
+            logging.error("Could not find '%s' to scan for exclusion markers...", source)
+            setExitCode("excl_not_found") # Set exit code because of error
+
+def scanExclusionMarkers(fastcov_json, jobs, exclude_branches_sw, include_branches_sw, min_chunk_size, fallback_encodings):
+    chunk_size = max(min_chunk_size, int(len(fastcov_json["sources"]) / jobs) + 1)
+
+    threads = []
+    for chunk in chunks(list(fastcov_json["sources"].keys()), chunk_size):
+        t = threading.Thread(target=exclMarkerWorker, args=(fastcov_json["sources"], chunk, exclude_branches_sw, include_branches_sw, fallback_encodings))
+        threads.append(t)
+        t.start()
+
+    logging.info("Spawned {} threads each scanning at most {} source files".format(len(threads), chunk_size))
+    for t in threads:
+        t.join()
+
+def distillFunction(function_raw, functions):
+    function_name   = function_raw["name"]
+    # NOTE: need to explicitly cast all counts coming from gcov to int - this is because gcov's json library
+    # will pass as scientific notation (i.e. 12+e45)
+    start_line      = int(function_raw["start_line"])
+    execution_count = int(function_raw["execution_count"])
+    if function_name not in functions:
+        functions[function_name] = {
+            "start_line": start_line,
+            "execution_count": execution_count
+        }
+    else:
+        functions[function_name]["execution_count"] += execution_count
+
+def emptyBranchSet(branch1, branch2):
+    return (branch1["count"] == 0 and branch2["count"] == 0)
+
+def matchingBranchSet(branch1, branch2):
+    return (branch1["count"] == branch2["count"])
+
+def filterExceptionalBranches(branches):
+    filtered_branches = []
+    exception_branch = False
+    for i in range(0, len(branches), 2):
+        if i+1 >= len(branches):
+            filtered_branches.append(branches[i])
+            break
+
+        # Filter exceptional branch noise
+        if branches[i+1]["throw"]:
+            exception_branch = True
+            continue
+
+        # Filter initializer list noise
+        if exception_branch and emptyBranchSet(branches[i], branches[i+1]) and len(filtered_branches) >= 2 and matchingBranchSet(filtered_branches[-1], filtered_branches[-2]):
+            return []
+
+        filtered_branches.append(branches[i])
+        filtered_branches.append(branches[i+1])
+
+    return filtered_branches
+
+def distillLine(line_raw, lines, branches, include_exceptional_branches):
+    line_number = int(line_raw["line_number"])
+    count       = int(line_raw["count"])
+    if line_number not in lines:
+        lines[line_number] = count
+    else:
+        lines[line_number] += count
+
+    # Filter out exceptional branches by default unless requested otherwise
+    if not include_exceptional_branches:
+        line_raw["branches"] = filterExceptionalBranches(line_raw["branches"])
+
+    # Increment all branch counts
+    for i, branch in enumerate(line_raw["branches"]):
+        if line_number not in branches:
+            branches[line_number] = []
+        blen = len(branches[line_number])
+        glen = len(line_raw["branches"])
+        if blen < glen:
+            branches[line_number] += [0] * (glen - blen)
+        branches[line_number][i] += int(branch["count"])
+
+def distillSource(source_raw, sources, test_name, include_exceptional_branches):
+    source_name = source_raw["file_abs"]
+    if source_name not in sources:
+        sources[source_name] = {
+            test_name: {
+                "functions": {},
+                "branches": {},
+                "lines": {}
+            }
+        }
+
+    for function in source_raw["functions"]:
+        distillFunction(function, sources[source_name][test_name]["functions"])
+
+    for line in source_raw["lines"]:
+        distillLine(line, sources[source_name][test_name]["lines"], sources[source_name][test_name]["branches"], include_exceptional_branches)
+
+def dumpToJson(intermediate, output):
+    with open(output, "w") as f:
+        json.dump(intermediate, f)
+
+def getGcovFilterOptions(args):
+    return {
+        "sources": set([os.path.abspath(s) for s in args.sources]), #Make paths absolute, use set for fast lookups
+        "include": args.includepost,
+        "exclude": args.excludepost,
+    }
+
+def addDicts(dict1, dict2):
+    """Add dicts together by value. i.e. addDicts({"a":1,"b":0}, {"a":2}) == {"a":3,"b":0}."""
+    result = {k:v for k,v in dict1.items()}
+    for k,v in dict2.items():
+        if k in result:
+            result[k] += v
+        else:
+            result[k] = v
+
+    return result
+
+def addLists(list1, list2):
+    """Add lists together by value. i.e. addLists([1,1], [2,2]) == [3,3]."""
+    # Find big list and small list
+    blist, slist = list(list2), list(list1)
+    if len(list1) > len(list2):
+        blist, slist = slist, blist
+
+    # Overlay small list onto big list
+    for i, b in enumerate(slist):
+        blist[i] += b
+
+    return blist
+
+def combineReports(base, overlay):
+    for source, scov in overlay["sources"].items():
+        # Combine Source Coverage
+        if source not in base["sources"]:
+            base["sources"][source] = scov
+            continue
+
+        for test_name, tcov in scov.items():
+            # Combine Source Test Name Coverage
+            if test_name not in base["sources"][source]:
+                base["sources"][source][test_name] = tcov
+                continue
+
+            # Drill down and create convenience variable
+            base_data = base["sources"][source][test_name]
+
+            # Combine Line Coverage
+            base_data["lines"] = addDicts(base_data["lines"], tcov["lines"])
+
+            # Combine Branch Coverage
+            for branch, cov in tcov["branches"].items():
+                if branch not in base_data["branches"]:
+                    base_data["branches"][branch] = cov
+                else:
+                    base_data["branches"][branch] = addLists(base_data["branches"][branch], cov)
+
+            # Combine Function Coverage
+            for function, cov in tcov["functions"].items():
+                if function not in base_data["functions"]:
+                    base_data["functions"][function] = cov
+                else:
+                    base_data["functions"][function]["execution_count"] += cov["execution_count"]
+
+def parseInfo(path):
+    """Parse an lcov .info file into fastcov json."""
+    fastcov_json = {
+        "sources": {}
+    }
+
+    with open(path) as f:
+        for line in f:
+            if line.startswith("TN:"):
+                current_test_name = line[3:].strip()
+            elif line.startswith("SF:"):
+                current_sf = line[3:].strip()
+                fastcov_json["sources"][current_sf] = {
+                    current_test_name: {
+                        "functions": {},
+                        "branches": {},
+                        "lines": {},
+                    }
+                }
+                current_data = fastcov_json["sources"][current_sf][current_test_name]
+            elif line.startswith("FN:"):
+                line_num, function_name = line[3:].strip().split(",")
+                current_data["functions"][function_name] = {}
+                current_data["functions"][function_name]["start_line"] = int(line_num)
+            elif line.startswith("FNDA:"):
+                count, function_name = line[5:].strip().split(",")
+                current_data["functions"][function_name]["execution_count"] = int(count)
+            elif line.startswith("DA:"):
+                line_num, count = line[3:].strip().split(",")
+                current_data["lines"][line_num] = int(count)
+            elif line.startswith("BRDA:"):
+                branch_tokens = line[5:].strip().split(",")
+                line_num, count = branch_tokens[0], branch_tokens[-1]
+                if line_num not in current_data["branches"]:
+                    current_data["branches"][line_num] = []
+                current_data["branches"][line_num].append(int(count))
+
+    return fastcov_json
+
+def convertKeysToInt(report):
+    for source in report["sources"].keys():
+        for test_name in report["sources"][source].keys():
+            report_data = report["sources"][source][test_name]
+            report_data["lines"]    = {int(k):v for k,v in report_data["lines"].items()}
+            report_data["branches"] = {int(k):v for k,v in report_data["branches"].items()}
+
+def parseAndCombine(paths):
+    base_report = {}
+
+    for path in paths:
+        if path.endswith(".json"):
+            with open(path) as f:
+                report = json.load(f)
+        elif path.endswith(".info"):
+            report = parseInfo(path)
+        else:
+            logging.error("Currently only fastcov .json and lcov .info supported for combine operations, aborting due to %s...\n", path)
+            sys.exit(EXIT_CODES["unsupported_coverage_format"])
+
+        # In order for sorting to work later when we serialize,
+        # make sure integer keys are int
+        convertKeysToInt(report)
+
+        if not base_report:
+            base_report = report
+            logging.info("Setting {} as base report".format(path))
+        else:
+            combineReports(base_report, report)
+            logging.info("Adding {} to base report".format(path))
+
+    return base_report
+
+def getCombineCoverage(args):
+    logging.info("Performing combine operation")
+    fastcov_json = parseAndCombine(args.combine)
+    filterFastcov(fastcov_json, args)
+    return fastcov_json
+
+def getGcovCoverage(args):
+    # Need at least python 3.5 because of use of recursive glob
+    checkPythonVersion(sys.version_info[0:2])
+
+    # Need at least gcov 9.0.0 because that's when gcov JSON and stdout streaming was introduced
+    checkGcovVersion(getGcovVersion(args.gcov))
+
+    # Get list of gcda files to process
+    coverage_files = findCoverageFiles(args.directory, args.coverage_files, args.use_gcno)
+
+    # If gcda/gcno filtering is enabled, filter them out now
+    if args.excludepre:
+        coverage_files = getFilteredCoverageFiles(coverage_files, args.excludepre)
+        logging.info("Found {} coverage files after filtering".format(len(coverage_files)))
+
+    # We "zero" the "counters" by simply deleting all gcda files
+    if args.zerocounters:
+        removeFiles(coverage_files)
+        logging.info("Removed {} .gcda files".format(len(coverage_files)))
+        sys.exit()
+
+    # Fire up one gcov per cpu and start processing gcdas
+    gcov_filter_options = getGcovFilterOptions(args)
+    fastcov_json = processGcdas(args, coverage_files, gcov_filter_options)
+
+    # Summarize processing results
+    logging.info("Processed {} .gcov files ({} total, {} skipped)".format(GCOVS_TOTAL - GCOVS_SKIPPED, GCOVS_TOTAL, GCOVS_SKIPPED))
+    logging.debug("Final report will contain coverage for the following %d source files:\n    %s", len(fastcov_json["sources"]), "\n    ".join(fastcov_json["sources"]))
+
+    return fastcov_json
+
+def dumpFile(fastcov_json, args):
+    if args.lcov:
+        dumpToLcovInfo(fastcov_json, args.output)
+        logging.info("Created lcov info file '{}'".format(args.output))
+    else:
+        dumpToJson(fastcov_json, args.output)
+        logging.info("Created fastcov json file '{}'".format(args.output))
+
+def tupleToDotted(tup):
+    return ".".join(map(str, tup))
+
+def parseArgs():
+    parser = argparse.ArgumentParser(description='A parallel gcov wrapper for fast coverage report generation')
+    parser.add_argument('-z', '--zerocounters', dest='zerocounters', action="store_true", help='Recursively delete all gcda files')
+
+    # Enable Branch Coverage
+    parser.add_argument('-b', '--branch-coverage', dest='branchcoverage', action="store_true", help='Include only the most useful branches in the coverage report.')
+    parser.add_argument('-B', '--exceptional-branch-coverage', dest='xbranchcoverage', action="store_true", help='Include ALL branches in the coverage report (including potentially noisy exceptional branches).')
+    parser.add_argument('-A', '--exclude-br-lines-starting-with', dest='exclude_branches_sw', nargs="+", metavar='', default=[], help='Exclude branches from lines starting with one of the provided strings (i.e. assert, return, etc.)')
+    parser.add_argument('-a', '--include-br-lines-starting-with', dest='include_branches_sw', nargs="+", metavar='', default=[], help='Include only branches from lines starting with one of the provided strings (i.e. if, else, while, etc.)')
+    parser.add_argument('-X', '--skip-exclusion-markers', dest='skip_exclusion_markers', action="store_true", help='Skip reading source files to search for lcov exclusion markers (such as "LCOV_EXCL_LINE")')
+    parser.add_argument('-x', '--scan-exclusion-markers', dest='scan_exclusion_markers', action="store_true", help='(Combine operations) Force reading source files to search for lcov exclusion markers (such as "LCOV_EXCL_LINE")')
+
+    # Capture untested file coverage as well via gcno
+    parser.add_argument('-n', '--process-gcno', dest='use_gcno', action="store_true", help='Process both gcno and gcda coverage files. This option is useful for capturing untested files in the coverage report.')
+
+    # Filtering Options
+    parser.add_argument('-s', '--source-files', dest='sources',     nargs="+", metavar='', default=[], help='Filter: Specify exactly which source files should be included in the final report. Paths must be either absolute or relative to current directory.')
+    parser.add_argument('-e', '--exclude',      dest='excludepost', nargs="+", metavar='', default=[], help='Filter: Exclude source files from final report if they contain one of the provided substrings (i.e. /usr/include test/, etc.)')
+    parser.add_argument('-i', '--include',      dest='includepost', nargs="+", metavar='', default=[], help='Filter: Only include source files in final report that contain one of the provided substrings (i.e. src/ etc.)')
+    parser.add_argument('-f', '--gcda-files',   dest='coverage_files',  nargs="+", metavar='', default=[], help='Filter: Specify exactly which gcda or gcno files should be processed. Note that specifying gcno causes both gcno and gcda to be processed.')
+    parser.add_argument('-E', '--exclude-gcda', dest='excludepre',  nargs="+", metavar='', default=[], help='Filter: Exclude gcda or gcno files from being processed via simple find matching (not regex)')
+
+    parser.add_argument('-g', '--gcov', dest='gcov', default='gcov', help='Which gcov binary to use')
+
+    parser.add_argument('-d', '--search-directory', dest='directory', default=".", help='Base directory to recursively search for gcda files (default: .)')
+    parser.add_argument('-c', '--compiler-directory', dest='cdirectory', default=".", help='Base directory compiler was invoked from (default: .) \
+                                                                                            This needs to be set if invoking fastcov from somewhere other than the base compiler directory.')
+
+    parser.add_argument('-j', '--jobs', dest='jobs', type=int, default=multiprocessing.cpu_count(), help='Number of parallel gcov to spawn (default: {}).'.format(multiprocessing.cpu_count()))
+    parser.add_argument('-m', '--minimum-chunk-size', dest='minimum_chunk', type=int, default=5,    help='Minimum number of files a thread should process (default: 5). \
+                                                                                                          If you have only 4 gcda files but they are monstrously huge, you could change this value to a 1 so that each thread will only process 1 gcda. Otherwise fastcov will spawn only 1 thread to process all of them.')
+
+    parser.add_argument('-F', '--fallback-encodings', dest='fallback_encodings', nargs="+", metavar='', default=[], help='List of encodings to try if opening a source file with the default fails (i.e. latin1, etc.). This option is not usually needed.')
+
+    parser.add_argument('-l', '--lcov',   dest='lcov',   action="store_true",     help='Output in lcov info format instead of fastcov json')
+    parser.add_argument('-o', '--output', dest='output', default="coverage.json", help='Name of output file (default: coverage.json)')
+    parser.add_argument('-q', '--quiet',  dest='quiet',  action="store_true",     help='Suppress output to stdout')
+
+    parser.add_argument('-t', '--test-name',     dest='test_name', default="", help='Specify a test name for the coverage. Equivalent to lcov\'s `-t`.')
+    parser.add_argument('-C', '--add-tracefile', dest='combine',   nargs="+",  help='Combine multiple coverage files into one. If this flag is specified, fastcov will do a combine operation instead invoking gcov. Equivalent to lcov\'s `-a`.')
+
+    parser.add_argument('-V', '--verbose', dest="verbose", action="store_true", help="Print more detailed information about what fastcov is doing")
+    parser.add_argument('-v', '--version', action="version", version='%(prog)s {version}'.format(version=__version__), help="Show program's version number and exit")
+
+    args = parser.parse_args()
+
+    return args
+
+def checkPythonVersion(version):
+    """Exit if the provided python version is less than the supported version."""
+    if version < MINIMUM_PYTHON:
+        sys.stderr.write("Minimum python version {} required, found {}\n".format(tupleToDotted(MINIMUM_PYTHON), tupleToDotted(version)))
+        sys.exit(EXIT_CODES["python_version"])
+
+def checkGcovVersion(version):
+    """Exit if the provided gcov version is less than the supported version."""
+    if version < MINIMUM_GCOV:
+        sys.stderr.write("Minimum gcov version {} required, found {}\n".format(tupleToDotted(MINIMUM_GCOV), tupleToDotted(version)))
+        sys.exit(EXIT_CODES["gcov_version"])
+
+def setupLogging(quiet, verbose):
+    handler = logging.StreamHandler()
+    handler.setFormatter(FastcovFormatter("[%(levelname)s]: %(message)s"))
+
+    root = logging.getLogger()
+    root.setLevel(logging.INFO)
+    root.addHandler(handler)
+
+    if not quiet:
+        logging.disable(level=logging.NOTSET) # Re-enable logging
+
+    if verbose:
+        root.setLevel(logging.DEBUG)
+
+def main():
+    args = parseArgs()
+
+    # Setup logging
+    setupLogging(args.quiet, args.verbose)
+
+    # Get report from appropriate source
+    if args.combine:
+        fastcov_json = getCombineCoverage(args)
+        skip_exclusion_markers = not args.scan_exclusion_markers
+    else:
+        fastcov_json = getGcovCoverage(args)
+        skip_exclusion_markers = args.skip_exclusion_markers
+
+    # Scan for exclusion markers
+    if not skip_exclusion_markers:
+        scanExclusionMarkers(fastcov_json, args.jobs, args.exclude_branches_sw, args.include_branches_sw, args.minimum_chunk, args.fallback_encodings)
+        logging.info("Scanned {} source files for exclusion markers".format(len(fastcov_json["sources"])))
+
+    # Dump to desired file format
+    dumpFile(fastcov_json, args)
+
+    # If there was an error along the way, but we still completed the pipeline...
+    if EXIT_CODE:
+        sys.exit(EXIT_CODE)
+
+# Set package version... it's way down here so that we can call tupleToDotted
+__version__ = tupleToDotted(FASTCOV_VERSION)
+
+if __name__ == '__main__':
+    main()
@@ -1,257 +0,0 @@
-#!/usr/bin/env perl
-# See copyright, etc in below POD section.
-######################################################################
-
-use warnings;
-use Getopt::Long;
-#use Data::Dumper; $Data::Dumper::Indent=1; $Data::Dumper::Sortkeys=1; #Debug
-use IO::File;
-use IO::Dir;
-use Pod::Usage;
-use strict;
-use vars qw($Debug);
-
-our $VERSION = '0.001';
-our $Opt_Widen = 1;
-
-#======================================================================
-# main
-
-autoflush STDOUT 1;
-autoflush STDERR 1;
-Getopt::Long::config("no_auto_abbrev");
-if (! GetOptions (
-          "debug"       => sub { $Debug = 1; },
-          "help"        => sub { print "Version $VERSION\n";
-                                 pod2usage(-verbose=>2, -exitval => 0,
-                                           output=>\*STDOUT, -noperldoc=>1); },
-          "narrow!"     => sub { $Opt_Widen = 0; },
-          "version"     => sub { print "Version $VERSION\n"; exit(0); },
-          "widen!"      => sub { $Opt_Widen = 1; },  # Default, undocumented
-          "<>"          => sub { die "%Error: Unknown parameter: $_[0]\n"; },
-    )) {
-    die "%Error: Bad usage, try 'git_untabify --help'\n";
-}
-
-read_patch();
-
-#######################################################################
-
-sub read_patch {
-    my $filename = undef;
-    my $lineno = 0;
-    my $hunk = 0;
-    my $editlines = {};
-    while (defined(my $line = <STDIN>)) {
-        chomp $line;
-        if ($line =~ m!^\+\+\+ b/(.*)!) {
-            find_edits($editlines);
-            edit_file($filename, $editlines);
-            $filename = $1;
-            $lineno = 0;
-            $editlines = {};
-            print "FILE $filename\n" if $Debug;
-        }
-        elsif ($line  =~ m!^@@ -?[0-9]+,?[0-9]* \+?([0-9]+)!) {
-            $lineno = $1 - 1;
-            ++$hunk;
-            print "  LINE $1  $line" if $Debug;
-        }
-        elsif ($line  =~ m!^ !) {
-            ++$lineno;
-            $editlines->{$lineno} = {line => $line,
-                                     hunk => $hunk,
-                                     user_edit => 0, };
-        }
-        elsif ($line  =~ m!^\+!) {
-            ++$lineno;
-            print "  $lineno: $line" if $Debug;
-            $editlines->{$lineno} = {line => $line,
-                                     hunk => $hunk,
-                                     user_edit => 1, };
-        }
-    }
-    find_edits($editlines);
-    edit_file($filename, $editlines);
-}
-
-sub find_edits {
-    my $editlines = shift;
-    # Expand edit regions so if have edited line, non-edited line, edited
-    # line, we will tab expand the middle ones.
-    my %hunk_firstlines;
-    foreach my $lineno (sort {$a <=> $b} keys %$editlines) {
-        my $hunk = $editlines->{$lineno}{hunk};
-        $hunk_firstlines{$hunk} ||= $lineno if $editlines->{$lineno}{user_edit};
-    }
-    my %hunk_lastlines;
-    foreach my $lineno (sort {$b <=> $a} keys %$editlines) {
-        my $hunk = $editlines->{$lineno}{hunk};
-        $hunk_lastlines{$hunk} ||= $lineno if $editlines->{$lineno}{user_edit};
-    }
-
-    if ($Opt_Widen) {
-        # Expand to include }'s that finish basic block
-        foreach my $hunk (keys %hunk_lastlines) {
-            while (my $lineno = $hunk_lastlines{$hunk}) {
-                ++$lineno;
-                if (($editlines->{$lineno}{line} || "")
-                    =~ /^[+ ]\s+}[ \t};]*$/) {
-                    $hunk_lastlines{$hunk} = $lineno;
-                } else {
-                    last;
-                }
-            }
-        }
-        # Expand to always untabify at least 3 lines (so that future diff will
-        # have non-tabs within a edit hunk distance
-        foreach my $hunk (keys %hunk_firstlines) {
-            if ($hunk_firstlines{$hunk} == $hunk_lastlines{$hunk}) {
-                --$hunk_firstlines{$hunk};
-                ++$hunk_lastlines{$hunk};
-            }
-            elsif ($hunk_firstlines{$hunk}+1 == $hunk_lastlines{$hunk}) {
-                ++$hunk_lastlines{$hunk};
-            }
-        }
-    }
-
-    foreach my $lineno (sort {$a <=> $b} keys %$editlines) {
-        if (($editlines->{$lineno}{line}||"") =~ /\t/) {
-            my $hunk = $editlines->{$lineno}{hunk};
-            if ($hunk_firstlines{$hunk} <= $lineno && $hunk_lastlines{$hunk} >= $lineno) {
-                $editlines->{$lineno}{editit} = 1;
-            }
-        }
-    }
-}
-
-sub edit_file {
-    my $filename = shift;
-    my $editlines = shift;
-
-    my @editits;
-    foreach my $lineno (sort {$a <=> $b} keys %$editlines) {
-        push @editits, $lineno if $editlines->{$lineno}{editit};
-    }
-
-    return if $#editits < 0;
-    if (ignore($filename)) {
-        print "%Warning: Ignoring $filename\n";
-        return;
-    }
-    print "Edit $filename ",join(",",@editits),"\n";
-
-    my $lineno = 0;
-    my @out;
-    {
-        my $fh = IO::File->new("<$filename") or die "%Error: $! $filename\n";
-        while (defined(my $line = $fh->getline)) {
-            ++$lineno;
-            if ($editlines->{$lineno}{editit}) {
-                print $line;
-                push @out, untabify($line);
-            } else {
-                push @out, $line;
-            }
-        }
-        $fh->close;
-    }
-    {
-        my $fh = IO::File->new(">${filename}.untab") or die "%Error: $! ${filename}.untab,";
-        $fh->print(join('',@out));
-        $fh->close;
-
-        my ($dev,$ino,$mode) = stat($filename);
-        chmod $mode, "${filename}.untab";
-    }
-
-    rename("${filename}.untab", $filename) or die "%Error: $! ${filename}.untab,";
-}
-
-sub ignore {
-    my $filename = shift;
-    return 1 if ($filename =~ /(Makefile|\.mk)/);
-    return 1 if ($filename =~ /\.(y|l|out|vcd)$/);
-    return 1 if ($filename =~ /gtkwave/);
-    #
-    return 0 if ($filename =~ /\.(sv|v|vh|svh|h|vc|cpp|pl)$/);
-    return 0;
-}
-
-sub untabify {
-    my $line = shift;
-    my $out = "";
-    my $col = 0;
-    foreach my $c (split //, $line) {
-        if ($c eq "\t") {
-            my $destcol = int(($col+8)/8)*8;
-            while ($col < $destcol) { ++$col; $out .= " "; }
-        } else {
-            $out .= $c;
-            $col++;
-        }
-    }
-    return $out;
-}
-
-#######################################################################
-__END__
-
-=pod
-
-=head1 NAME
-
-git_untabify - Pipe a git diff report and untabify differences
-
-=head1 SYNOPSIS
-
-  git diff a..b | git_untabify
-
-=head1 DESCRIPTION
-
-Take a patch file, and edit the files in the destination patch list to
-untabify the related patch lines.
-
-=head1 ARGUMENTS
-
-=over 4
-
-=item --help
-
-Displays this message and program version and exits.
-
-=item --narrow
-
-Only edit lines which the user edited.
-
-If not provided, also edit other lines within at least a 3 line area around
-the edit, and between any edits within the same hunk.
-
-=item --version
-
-Displays program version and exits.
-
-=back
-
-=head1 DISTRIBUTION
-
-Copyright 2005-2020 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.
-
-SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
-
-=head1 AUTHORS
-
-Wilson Snyder <[email protected]>
-
-=head1 SEE ALSO
-
-=cut
-
-######################################################################
-### Local Variables:
-### compile-command: "./git_untabify "
-### End:
@@ -69,22 +69,23 @@ dbg: ../bin/verilator_bin_dbg ../bin/verilator_coverage_bin_dbg
 	$(MAKE) -C obj_dbg       TGT=../$@ VL_DEBUG=1 VL_VLCOV=1 -f ../Makefile_obj serial_vlcov
 	$(MAKE) -C obj_dbg       TGT=../$@ VL_DEBUG=1 VL_VLCOV=1 -f ../Makefile_obj

+ifneq ($(VERILATOR_NO_OPT_BUILD),1)  # Faster laptop development... don't rebuild each commit
+ ifneq ($(UNDER_GIT),)	# If local git tree... else don't burden users
+GIT_CHANGE_DEP = ${srcdir}/../.git/logs/HEAD
+ endif
+endif
+
 prefiles::
 prefiles:: config_rev.h
-ifneq ($(UNDER_GIT),)	# If local git tree... Else don't burden users
 # This output goes into srcdir if locally configured, as we need to distribute it as part of the kit.
-config_rev.h:	${srcdir}/config_rev.pl ${srcdir}/../.git/logs/HEAD
+config_rev.h:	${srcdir}/config_rev.pl $(GIT_CHANGE_DEP)
 	$(PERL) ${srcdir}/config_rev.pl ${srcdir} >$@
-else
-config_rev.h:	${srcdir}/config_rev.pl
-	$(PERL) ${srcdir}/config_rev.pl ${srcdir} >$@
-endif

 maintainer-copy::
 clean mostlyclean distclean maintainer-clean::
 	-rm -rf obj_* *.log *.dmp *.vpd core
 	-rm -f *.o *.d perlxsi.c *_gen_*
-	-rm -f *__gen*
+	-rm -f *__gen* obj_*
 	-rm -f .objcache*

 distclean maintainer-clean::
@@ -203,6 +203,7 @@ RAW_OBJS = \
 	V3GraphPathChecker.o \
 	V3GraphTest.o \
 	V3Hashed.o \
+	V3HierBlock.o \
 	V3Inline.o \
 	V3Inst.o \
 	V3InstrCount.o \
@@ -211,11 +212,13 @@ RAW_OBJS = \
 	V3LinkCells.o \
 	V3LinkDot.o \
 	V3LinkJump.o \
+	V3LinkInc.o \
 	V3LinkLValue.o \
 	V3LinkLevel.o \
 	V3LinkParse.o \
 	V3LinkResolve.o \
 	V3Localize.o \
+	V3MergeCond.o \
 	V3Name.o \
 	V3Number.o \
 	V3Options.o \
@@ -246,6 +249,7 @@ RAW_OBJS = \
 	V3Undriven.o \
 	V3Unknown.o \
 	V3Unroll.o \
+	V3Waiver.o \
 	V3Width.o \
 	V3WidthSel.o \

@@ -275,7 +279,6 @@ V3__CONCAT.cpp: $(addsuffix .cpp, $(basename $(RAW_OBJS)))

 $(TGT): $(PREDEP_H) $(OBJS)
 	@echo "      Linking $@..."
-	-rm -rf $@ [email protected]
 	${LINK} ${LDFLAGS} -o $@ $(OBJS) $(CCMALLOC) ${LIBS}

 V3Number_test: V3Number_test.o
@@ -287,21 +290,21 @@ V3Number_test: V3Number_test.o
 	$(PERL) $(ASTGEN) -I$(srcdir) $*.cpp

 %.o:	%.cpp
-	$(OBJCACHE) ${CXX} ${CXXFLAGS} ${CPPFLAGSWALL} -c $<
+	$(OBJCACHE) ${CXX} ${CXXFLAGS} ${CPPFLAGSWALL} -c $< -o $@
 %.o:	%.c
-	$(OBJCACHE) ${CC}  ${CFLAGS} ${CPPFLAGSWALL} -c $<
+	$(OBJCACHE) ${CC}  ${CFLAGS} ${CPPFLAGSWALL} -c $< -o $@

 V3ParseLex.o:	V3ParseLex.cpp V3Lexer.yy.cpp V3ParseBison.c
-	$(OBJCACHE) ${CXX} ${CXXFLAGS} ${CPPFLAGSPARSER} -c $<
+	$(OBJCACHE) ${CXX} ${CXXFLAGS} ${CPPFLAGSPARSER} -c $< -o $@

 V3ParseGrammar.o:	V3ParseGrammar.cpp V3ParseBison.c
-	$(OBJCACHE) ${CXX} ${CXXFLAGS} ${CPPFLAGSPARSER} -c $<
+	$(OBJCACHE) ${CXX} ${CXXFLAGS} ${CPPFLAGSPARSER} -c $< -o $@

 V3ParseImp.o:	V3ParseImp.cpp V3ParseBison.c
-	$(OBJCACHE) ${CXX} ${CXXFLAGS} ${CPPFLAGSPARSER} -c $<
+	$(OBJCACHE) ${CXX} ${CXXFLAGS} ${CPPFLAGSPARSER} -c $< -o $@

 V3PreProc.o:	V3PreProc.cpp V3PreLex.yy.cpp
-	$(OBJCACHE) ${CXX} ${CXXFLAGS} ${CPPFLAGSPARSER} -c $<
+	$(OBJCACHE) ${CXX} ${CXXFLAGS} ${CPPFLAGSPARSER} -c $< -o $@

 #### Generated files

@@ -36,7 +36,7 @@
 #include "V3Const.h"
 #include "V3SenTree.h"  // for SenTreeSet

-#include VL_INCLUDE_UNORDERED_MAP
+#include <unordered_map>

 //***** See below for main transformation engine

@@ -50,38 +50,37 @@ protected:

 class ActiveNamer : public ActiveBaseVisitor {
 private:
-    typedef std::map<string, AstActive*> ActiveNameMap;
    // STATE
-    AstScope* m_scopep;  // Current scope to add statement to
-    AstActive* m_iActivep;  // For current scope, the IActive we're building
-    AstActive* m_cActivep;  // For current scope, the SActive(combo) we're building
+    AstScope* m_scopep = nullptr;  // Current scope to add statement to
+    AstActive* m_iActivep = nullptr;  // For current scope, the IActive we're building
+    AstActive* m_cActivep = nullptr;  // For current scope, the SActive(combo) we're building

    SenTreeSet m_activeSens;  // Sen lists for each active we've made
-    typedef vl_unordered_map<AstSenTree*, AstActive*> ActiveMap;
+    typedef std::unordered_map<AstSenTree*, AstActive*> ActiveMap;
    ActiveMap m_activeMap;  // Map sentree to active, for folding.

    // METHODS
    void addActive(AstActive* nodep) {
-        UASSERT_OBJ(m_scopep, nodep, "NULL scope");
+        UASSERT_OBJ(m_scopep, nodep, "nullptr scope");
        m_scopep->addActivep(nodep);
    }
    // VISITORS
-    virtual void visit(AstScope* nodep) VL_OVERRIDE {
+    virtual void visit(AstScope* nodep) override {
        m_scopep = nodep;
-        m_iActivep = NULL;
-        m_cActivep = NULL;
+        m_iActivep = nullptr;
+        m_cActivep = nullptr;
        m_activeSens.clear();
        m_activeMap.clear();
        iterateChildren(nodep);
        // Don't clear scopep, the namer persists beyond this visit
    }
-    virtual void visit(AstSenTree* nodep) VL_OVERRIDE {
+    virtual void visit(AstSenTree* nodep) override {
        // Simplify sensitivity list
        VL_DO_DANGLING(V3Const::constifyExpensiveEdit(nodep), nodep);
    }
    //--------------------
-    virtual void visit(AstNodeStmt*) VL_OVERRIDE {}  // Accelerate
-    virtual void visit(AstNode* nodep) VL_OVERRIDE { iterateChildren(nodep); }
+    virtual void visit(AstNodeStmt*) override {}  // Accelerate
+    virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }

 public:
    // METHODS
@@ -107,10 +106,10 @@ public:
    AstActive* getActive(FileLine* fl, AstSenTree* sensesp) {
        // Return a sentree in this scope that matches given sense list.

-        AstActive* activep = NULL;
+        AstActive* activep = nullptr;
        AstSenTree* activeSenp = m_activeSens.find(sensesp);
        if (activeSenp) {
-            ActiveMap::iterator it = m_activeMap.find(activeSenp);
+            const auto it = m_activeMap.find(activeSenp);
            UASSERT(it != m_activeMap.end(), "Corrupt active map");
            activep = it->second;
        }
@@ -130,14 +129,9 @@ public:
        return activep;
    }

-public:
    // CONSTRUCTORS
-    ActiveNamer() {
-        m_scopep = NULL;
-        m_iActivep = NULL;
-        m_cActivep = NULL;
-    }
-    virtual ~ActiveNamer() {}
+    ActiveNamer() {}
+    virtual ~ActiveNamer() override {}
    void main(AstScope* nodep) { iterate(nodep); }
 };

@@ -146,14 +140,14 @@ public:

 class ActiveDlyVisitor : public ActiveBaseVisitor {
 public:
-    enum CheckType { CT_SEQ, CT_COMBO, CT_INITIAL, CT_LATCH };
+    enum CheckType : uint8_t { CT_SEQ, CT_COMBO, CT_INITIAL, CT_LATCH };

 private:
    CheckType m_check;  // Combo logic or other
    AstNode* m_alwaysp;  // Always we're under
-    AstNode* m_assignp;  // In assign
+    AstNode* m_assignp = nullptr;  // In assign
    // VISITORS
-    virtual void visit(AstAssignDly* nodep) VL_OVERRIDE {
+    virtual void visit(AstAssignDly* nodep) override {
        if (m_check != CT_SEQ) {
            // Convert to a non-delayed assignment
            UINFO(5, "    ASSIGNDLY " << nodep << endl);
@@ -175,7 +169,7 @@ private:
            VL_DO_DANGLING(nodep->deleteTree(), nodep);
        }
    }
-    virtual void visit(AstAssign* nodep) VL_OVERRIDE {
+    virtual void visit(AstAssign* nodep) override {
        if (m_check == CT_SEQ) {
            AstNode* las = m_assignp;
            m_assignp = nodep;
@@ -183,7 +177,7 @@ private:
            m_assignp = las;
        }
    }
-    virtual void visit(AstVarRef* nodep) VL_OVERRIDE {
+    virtual void visit(AstVarRef* nodep) override {
        AstVar* varp = nodep->varp();
        if (m_check == CT_SEQ && m_assignp && !varp->isUsedLoopIdx()  // Ignore loop indices
            && !varp->isTemp()) {
@@ -202,17 +196,16 @@ private:
        }
    }
    //--------------------
-    virtual void visit(AstNode* nodep) VL_OVERRIDE { iterateChildren(nodep); }
+    virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }

 public:
    // CONSTRUCTORS
-    ActiveDlyVisitor(AstNode* nodep, CheckType check) {
-        m_alwaysp = nodep;
-        m_check = check;
-        m_assignp = NULL;
+    ActiveDlyVisitor(AstNode* nodep, CheckType check)
+        : m_check{check}
+        , m_alwaysp{nodep} {
        iterate(nodep);
    }
-    virtual ~ActiveDlyVisitor() {}
+    virtual ~ActiveDlyVisitor() override {}
 };

 //######################################################################
@@ -226,23 +219,23 @@ private:

    // STATE
    ActiveNamer m_namer;  // Tracking of active names
-    AstCFunc* m_scopeFinalp;  // Final function for this scope
-    bool m_itemCombo;  // Found a SenItem combo
-    bool m_itemSequent;  // Found a SenItem sequential
+    AstCFunc* m_scopeFinalp = nullptr;  // Final function for this scope
+    bool m_itemCombo = false;  // Found a SenItem combo
+    bool m_itemSequent = false;  // Found a SenItem sequential

    // VISITORS
-    virtual void visit(AstScope* nodep) VL_OVERRIDE {
+    virtual void visit(AstScope* nodep) override {
        // Create required actives and add to scope
        UINFO(4, " SCOPE   " << nodep << endl);
        // Clear last scope's names, and collect this scope's existing names
        m_namer.main(nodep);
-        m_scopeFinalp = NULL;
+        m_scopeFinalp = nullptr;
        iterateChildren(nodep);
    }
-    virtual void visit(AstActive* nodep) VL_OVERRIDE {
+    virtual void visit(AstActive* nodep) override {
        // Actives are being formed, so we can ignore any already made
    }
-    virtual void visit(AstInitial* nodep) VL_OVERRIDE {
+    virtual void visit(AstInitial* nodep) override {
        // Relink to IACTIVE, unless already under it
        UINFO(4, "    INITIAL " << nodep << endl);
        ActiveDlyVisitor dlyvisitor(nodep, ActiveDlyVisitor::CT_INITIAL);
@@ -250,28 +243,28 @@ private:
        nodep->unlinkFrBack();
        wantactivep->addStmtsp(nodep);
    }
-    virtual void visit(AstAssignAlias* nodep) VL_OVERRIDE {
+    virtual void visit(AstAssignAlias* nodep) override {
        // Relink to CACTIVE, unless already under it
        UINFO(4, "    ASSIGNW " << nodep << endl);
        AstActive* wantactivep = m_namer.getCActive(nodep->fileline());
        nodep->unlinkFrBack();
        wantactivep->addStmtsp(nodep);
    }
-    virtual void visit(AstAssignW* nodep) VL_OVERRIDE {
+    virtual void visit(AstAssignW* nodep) override {
        // Relink to CACTIVE, unless already under it
        UINFO(4, "    ASSIGNW " << nodep << endl);
        AstActive* wantactivep = m_namer.getCActive(nodep->fileline());
        nodep->unlinkFrBack();
        wantactivep->addStmtsp(nodep);
    }
-    virtual void visit(AstCoverToggle* nodep) VL_OVERRIDE {
+    virtual void visit(AstCoverToggle* nodep) override {
        // Relink to CACTIVE, unless already under it
        UINFO(4, "    COVERTOGGLE " << nodep << endl);
        AstActive* wantactivep = m_namer.getCActive(nodep->fileline());
        nodep->unlinkFrBack();
        wantactivep->addStmtsp(nodep);
    }
-    virtual void visit(AstFinal* nodep) VL_OVERRIDE {
+    virtual void visit(AstFinal* nodep) override {
        // Relink to CFUNC for the final
        UINFO(4, "    FINAL " << nodep << endl);
        if (!nodep->bodysp()) {  // Empty, Kill it.
@@ -317,14 +310,12 @@ private:

        if (!combo && !sequent) combo = true;  // If no list, Verilog 2000: always @ (*)
        if (combo && sequent) {
-            if (!v3Global.opt.bboxUnsup()) {
-                nodep->v3error("Unsupported: Mixed edge (pos/negedge) and activity "
-                               "(no edge) sensitive activity list");
-            }
+            nodep->v3warn(E_UNSUPPORTED, "Unsupported: Mixed edge (pos/negedge) and activity "
+                                         "(no edge) sensitive activity list");
            sequent = false;
        }

-        AstActive* wantactivep = NULL;
+        AstActive* wantactivep = nullptr;
        if (combo && !sequent) {
            // Combo:  Relink to ACTIVE(combo)
            wantactivep = m_namer.getCActive(nodep->fileline());
@@ -361,7 +352,7 @@ private:
            ActiveDlyVisitor dlyvisitor(nodep, ActiveDlyVisitor::CT_SEQ);
        }
    }
-    virtual void visit(AstAlways* nodep) VL_OVERRIDE {
+    virtual void visit(AstAlways* nodep) override {
        // Move always to appropriate ACTIVE based on its sense list
        UINFO(4, "    ALW   " << nodep << endl);
        // if (debug() >= 9) nodep->dumpTree(cout, "  Alw: ");
@@ -373,21 +364,13 @@ private:
        }
        visitAlways(nodep, nodep->sensesp(), nodep->keyword());
    }
-    virtual void visit(AstAlwaysPublic* nodep) VL_OVERRIDE {
+    virtual void visit(AstAlwaysPublic* nodep) override {
        // Move always to appropriate ACTIVE based on its sense list
        UINFO(4, "    ALWPub   " << nodep << endl);
        // if (debug() >= 9) nodep->dumpTree(cout, "  Alw: ");
        visitAlways(nodep, nodep->sensesp(), VAlwaysKwd::ALWAYS);
    }
-    virtual void visit(AstSenGate* nodep) VL_OVERRIDE {
-        AstSenItem* subitemp = nodep->sensesp();
-        UASSERT_OBJ(subitemp->edgeType() == VEdgeType::ET_ANYEDGE
-                        || subitemp->edgeType() == VEdgeType::ET_POSEDGE
-                        || subitemp->edgeType() == VEdgeType::ET_NEGEDGE,
-                    nodep, "Strange activity type under SenGate");
-        iterateChildren(nodep);
-    }
-    virtual void visit(AstSenItem* nodep) VL_OVERRIDE {
+    virtual void visit(AstSenItem* nodep) override {
        if (nodep->varrefp()) {
            if (AstBasicDType* basicp = nodep->varrefp()->dtypep()->basicp()) {
                if (basicp->isEventValue()) {
@@ -406,8 +389,9 @@ private:
        } else if (nodep->varrefp()) {
            // V3LinkResolve should have cleaned most of these up
            if (!nodep->varrefp()->width1()) {
-                nodep->v3error("Unsupported: Non-single bit wide signal pos/negedge sensitivity: "
-                               << nodep->varrefp()->prettyNameQ());
+                nodep->v3warn(E_UNSUPPORTED,
+                              "Unsupported: Non-single bit wide signal pos/negedge sensitivity: "
+                                  << nodep->varrefp()->prettyNameQ());
            }
            m_itemSequent = true;
            nodep->varrefp()->varp()->usedClock(true);
@@ -415,19 +399,14 @@ private:
    }

    //--------------------
-    virtual void visit(AstNodeMath*) VL_OVERRIDE {}  // Accelerate
-    virtual void visit(AstVarScope*) VL_OVERRIDE {}  // Accelerate
-    virtual void visit(AstNode* nodep) VL_OVERRIDE { iterateChildren(nodep); }
+    virtual void visit(AstNodeMath*) override {}  // Accelerate
+    virtual void visit(AstVarScope*) override {}  // Accelerate
+    virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }

 public:
    // CONSTRUCTORS
-    explicit ActiveVisitor(AstNetlist* nodep)
-        : m_scopeFinalp(NULL)
-        , m_itemCombo(false)
-        , m_itemSequent(false) {
-        iterate(nodep);
-    }
-    virtual ~ActiveVisitor() {}
+    explicit ActiveVisitor(AstNetlist* nodep) { iterate(nodep); }
+    virtual ~ActiveVisitor() override {}
 };

 //######################################################################
@@ -45,31 +45,31 @@ private:
    AstUser1InUse m_inuser1;

    // STATE
-    AstTopScope* m_topscopep;  // Top scope for adding sentrees under
+    AstTopScope* m_topscopep = nullptr;  // Top scope for adding sentrees under
    SenTreeFinder m_finder;  // Find global sentree's and add them

    // METHODS
    VL_DEBUG_FUNC;  // Declare debug()

    // VISITORS
-    virtual void visit(AstTopScope* nodep) VL_OVERRIDE {
+    virtual void visit(AstTopScope* nodep) override {
        m_topscopep = nodep;
-        m_finder.main(m_topscopep);
+        m_finder.init(m_topscopep);
        iterateChildren(nodep);
-        m_topscopep = NULL;
+        m_topscopep = nullptr;
    }
-    virtual void visit(AstNodeModule* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeModule* nodep) override {
        // Create required actives and add to module
        // We can start ordering at a module, or a scope
        UINFO(4, " MOD   " << nodep << endl);
        iterateChildren(nodep);
    }
-    virtual void visit(AstActive* nodep) VL_OVERRIDE {
+    virtual void visit(AstActive* nodep) override {
        UINFO(4, "   ACTIVE " << nodep << endl);
        // Remove duplicate clocks and such; sensesp() may change!
        V3Const::constifyExpensiveEdit(nodep);
        AstSenTree* sensesp = nodep->sensesp();
-        UASSERT_OBJ(sensesp, nodep, "NULL");
+        UASSERT_OBJ(sensesp, nodep, "nullptr");
        if (sensesp->sensesp() && VN_IS(sensesp->sensesp(), SenItem)
            && VN_CAST(sensesp->sensesp(), SenItem)->isNever()) {
            // Never executing.  Kill it.
@@ -89,7 +89,7 @@ private:
        }
        // Move the SENTREE for each active up to the global level.
        // This way we'll easily see what clock domains are identical
-        AstSenTree* wantp = m_finder.getSenTree(nodep->fileline(), sensesp);
+        AstSenTree* wantp = m_finder.getSenTree(sensesp);
        UINFO(4, "   lookdone\n");
        if (wantp != sensesp) {
            // Move the active's contents to the other active
@@ -108,36 +108,27 @@ private:
        // No need to do statements under it, they're already moved.
        // iterateChildren(nodep);
    }
-    virtual void visit(AstInitial* nodep) VL_OVERRIDE {  // LCOV_EXCL_LINE
+    virtual void visit(AstNodeProcedure* nodep) override {  // LCOV_EXCL_LINE
        nodep->v3fatalSrc("Node should have been under ACTIVE");
    }
-    virtual void visit(AstAssignAlias* nodep) VL_OVERRIDE {  // LCOV_EXCL_LINE
+    virtual void visit(AstAssignAlias* nodep) override {  // LCOV_EXCL_LINE
        nodep->v3fatalSrc("Node should have been under ACTIVE");
    }
-    virtual void visit(AstAssignW* nodep) VL_OVERRIDE {  // LCOV_EXCL_LINE
+    virtual void visit(AstAssignW* nodep) override {  // LCOV_EXCL_LINE
        nodep->v3fatalSrc("Node should have been under ACTIVE");
    }
-    virtual void visit(AstAlways* nodep) VL_OVERRIDE {  // LCOV_EXCL_LINE
+    virtual void visit(AstAlwaysPublic* nodep) override {  // LCOV_EXCL_LINE
        nodep->v3fatalSrc("Node should have been under ACTIVE");
    }
-    virtual void visit(AstAlwaysPublic* nodep) VL_OVERRIDE {  // LCOV_EXCL_LINE
-        nodep->v3fatalSrc("Node should have been under ACTIVE");
-    }
-    virtual void visit(AstFinal* nodep) VL_OVERRIDE {  // LCOV_EXCL_LINE
-        nodep->v3fatalSrc("Node should have been deleted");
-    }
    //--------------------
-    virtual void visit(AstNodeMath*) VL_OVERRIDE {}  // Accelerate
-    virtual void visit(AstVarScope*) VL_OVERRIDE {}  // Accelerate
-    virtual void visit(AstNode* nodep) VL_OVERRIDE { iterateChildren(nodep); }
+    virtual void visit(AstNodeMath*) override {}  // Accelerate
+    virtual void visit(AstVarScope*) override {}  // Accelerate
+    virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }

 public:
    // CONSTRUCTORS
-    explicit ActiveTopVisitor(AstNetlist* nodep)
-        : m_topscopep(NULL) {
-        iterate(nodep);
-    }
-    virtual ~ActiveTopVisitor() {}
+    explicit ActiveTopVisitor(AstNetlist* nodep) { iterate(nodep); }
+    virtual ~ActiveTopVisitor() override {}
 };

 //######################################################################
@@ -23,9 +23,6 @@
 #include "V3GraphDfa.h"
 #include "V3Stats.h"

-#include <cstdarg>
-#include <iomanip>
-
 //######################################################################
 // Assert class functions

@@ -37,9 +34,9 @@ private:
    AstUser1InUse m_inuser1;

    // STATE
-    AstNodeModule* m_modp;  // Last module
-    AstBegin* m_beginp;  // Last begin
-    unsigned m_modPastNum;  // Module past numbering
+    AstNodeModule* m_modp = nullptr;  // Last module
+    AstBegin* m_beginp = nullptr;  // Last begin
+    unsigned m_modPastNum = 0;  // Module past numbering
    VDouble0 m_statCover;  // Statistic tracking
    VDouble0 m_statAsNotImm;  // Statistic tracking
    VDouble0 m_statAsImm;  // Statistic tracking
@@ -77,15 +74,15 @@ private:
                        (v3Global.opt.assertOn()
                             ? static_cast<AstNode*>(new AstCMath(fl, "Verilated::assertOn()", 1))
                             : static_cast<AstNode*>(new AstConst(fl, AstConst::LogicFalse()))),
-                        nodep, NULL);
+                        nodep, nullptr);
        newp->user1(true);  // Don't assert/cover this if
        return newp;
    }

    AstNode* newFireAssertUnchecked(AstNode* nodep, const string& message) {
        // Like newFireAssert() but omits the asserts-on check
-        AstDisplay* dispp
-            = new AstDisplay(nodep->fileline(), AstDisplayType::DT_ERROR, message, NULL, NULL);
+        AstDisplay* dispp = new AstDisplay(nodep->fileline(), AstDisplayType::DT_ERROR, message,
+                                           nullptr, nullptr);
        AstNode* bodysp = dispp;
        replaceDisplay(dispp, "%%Error");  // Convert to standard DISPLAY format
        bodysp->addNext(new AstStop(nodep->fileline(), true));
@@ -115,9 +112,9 @@ private:
            sentreep->unlinkFrBack();
        }
        //
-        AstNode* bodysp = NULL;
+        AstNode* bodysp = nullptr;
        bool selfDestruct = false;
-        AstIf* ifp = NULL;
+        AstIf* ifp = nullptr;
        if (AstCover* snodep = VN_CAST(nodep, Cover)) {
            ++m_statCover;
            if (!v3Global.opt.coverageUser()) {
@@ -132,7 +129,7 @@ private:
            }

            if (bodysp && passsp) bodysp = bodysp->addNext(passsp);
-            ifp = new AstIf(nodep->fileline(), propp, bodysp, NULL);
+            ifp = new AstIf(nodep->fileline(), propp, bodysp, nullptr);
            bodysp = ifp;
        } else if (VN_IS(nodep, Assert)) {
            if (nodep->immediate()) {
@@ -144,7 +141,7 @@ private:
            if (failsp) failsp = newIfAssertOn(failsp);
            if (!failsp) failsp = newFireAssertUnchecked(nodep, "'assert' failed.");
            ifp = new AstIf(nodep->fileline(), propp, passsp, failsp);
-            // It's more LIKELY that we'll take the NULL if clause
+            // It's more LIKELY that we'll take the nullptr if clause
            // than the sim-killing else clause:
            ifp->branchPred(VBranchPred::BP_LIKELY);
            bodysp = newIfAssertOn(ifp);
@@ -172,11 +169,11 @@ private:
    }

    // VISITORS
-    virtual void visit(AstIf* nodep) VL_OVERRIDE {
+    virtual void visit(AstIf* nodep) override {
        if (nodep->user1SetOnce()) return;
        if (nodep->uniquePragma() || nodep->unique0Pragma()) {
            AstNodeIf* ifp = nodep;
-            AstNode* propp = NULL;
+            AstNode* propp = nullptr;
            bool hasDefaultElse = false;
            do {
                // If this statement ends with 'else if', then nextIf will point to the
@@ -229,7 +226,7 @@ private:
    }

    //========== Case assertions
-    virtual void visit(AstCase* nodep) VL_OVERRIDE {
+    virtual void visit(AstCase* nodep) override {
        iterateChildren(nodep);
        if (!nodep->user1SetOnce()) {
            bool has_default = false;
@@ -242,7 +239,7 @@ private:
                ++m_statAsFull;
                if (!has_default) {
                    nodep->addItemsp(new AstCaseItem(
-                        nodep->fileline(), NULL /*DEFAULT*/,
+                        nodep->fileline(), nullptr /*DEFAULT*/,
                        newFireAssert(nodep, "synthesis full_case, but non-match found")));
                }
            }
@@ -253,7 +250,7 @@ private:
                if (!has_default && !nodep->itemsp()) {
                    // Not parallel, but harmlessly so.
                } else {
-                    AstNode* propp = NULL;
+                    AstNode* propp = nullptr;
                    for (AstCaseItem* itemp = nodep->itemsp(); itemp;
                         itemp = VN_CAST(itemp->nextp(), CaseItem)) {
                        for (AstNode* icondp = itemp->condsp(); icondp; icondp = icondp->nextp()) {
@@ -290,7 +287,7 @@ private:
                        nodep->fileline(), new AstLogNot(nodep->fileline(), ohot),
                        newFireAssert(nodep,
                                      "synthesis parallel_case, but multiple matches found"),
-                        NULL);
+                        nullptr);
                    ifp->branchPred(VBranchPred::BP_UNLIKELY);
                    nodep->addNotParallelp(ifp);
                }
@@ -299,7 +296,7 @@ private:
    }

    //========== Past
-    virtual void visit(AstPast* nodep) VL_OVERRIDE {
+    virtual void visit(AstPast* nodep) override {
        iterateChildren(nodep);
        uint32_t ticks = 1;
        if (nodep->ticksp()) {
@@ -309,10 +306,11 @@ private:
        }
        UASSERT_OBJ(ticks >= 1, nodep, "0 tick should have been checked in V3Width");
        AstNode* inp = nodep->exprp()->unlinkFrBack();
-        AstVar* invarp = NULL;
+        AstVar* invarp = nullptr;
        AstSenTree* sentreep = nodep->sentreep();
        sentreep->unlinkFrBack();
-        AstAlways* alwaysp = new AstAlways(nodep->fileline(), VAlwaysKwd::ALWAYS, sentreep, NULL);
+        AstAlways* alwaysp
+            = new AstAlways(nodep->fileline(), VAlwaysKwd::ALWAYS, sentreep, nullptr);
        m_modp->addStmtp(alwaysp);
        for (uint32_t i = 0; i < ticks; ++i) {
            AstVar* outvarp = new AstVar(nodep->fileline(), AstVarType::MODULETEMP,
@@ -328,13 +326,13 @@ private:
        }
        nodep->replaceWith(inp);
    }
-    virtual void visit(AstSampled* nodep) VL_OVERRIDE {
+    virtual void visit(AstSampled* nodep) override {
        nodep->replaceWith(nodep->exprp()->unlinkFrBack());
        VL_DO_DANGLING(pushDeletep(nodep), nodep);
    }

    //========== Statements
-    virtual void visit(AstDisplay* nodep) VL_OVERRIDE {
+    virtual void visit(AstDisplay* nodep) override {
        iterateChildren(nodep);
        // Replace the special types with standard text
        if (nodep->displayType() == AstDisplayType::DT_INFO) {
@@ -347,54 +345,45 @@ private:
        }
    }

-    virtual void visit(AstAssert* nodep) VL_OVERRIDE {
+    virtual void visit(AstAssert* nodep) override {
        iterateChildren(nodep);
        newPslAssertion(nodep, nodep->failsp());
    }
-    virtual void visit(AstCover* nodep) VL_OVERRIDE {
+    virtual void visit(AstCover* nodep) override {
        iterateChildren(nodep);
-        newPslAssertion(nodep, NULL);
+        newPslAssertion(nodep, nullptr);
    }
-    virtual void visit(AstRestrict* nodep) VL_OVERRIDE {
+    virtual void visit(AstRestrict* nodep) override {
        iterateChildren(nodep);
        // IEEE says simulator ignores these
        VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
    }

-    virtual void visit(AstNodeModule* nodep) VL_OVERRIDE {
-        AstNodeModule* origModp = m_modp;
-        unsigned origPastNum = m_modPastNum;
+    virtual void visit(AstNodeModule* nodep) override {
+        VL_RESTORER(m_modp);
+        VL_RESTORER(m_modPastNum);
        {
            m_modp = nodep;
            m_modPastNum = 0;
            iterateChildren(nodep);
        }
-        m_modp = origModp;
-        m_modPastNum = origPastNum;
    }
-    virtual void visit(AstBegin* nodep) VL_OVERRIDE {
+    virtual void visit(AstBegin* nodep) override {
        // This code is needed rather than a visitor in V3Begin,
        // because V3Assert is called before V3Begin
-        AstBegin* lastp = m_beginp;
+        VL_RESTORER(m_beginp);
        {
            m_beginp = nodep;
            iterateChildren(nodep);
        }
-        m_beginp = lastp;
    }

-    virtual void visit(AstNode* nodep) VL_OVERRIDE { iterateChildren(nodep); }
+    virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }

 public:
    // CONSTRUCTORS
-    explicit AssertVisitor(AstNetlist* nodep) {
-        m_beginp = NULL;
-        m_modp = NULL;
-        m_modPastNum = 0;
-        // Process
-        iterate(nodep);
-    }
-    virtual ~AssertVisitor() {
+    explicit AssertVisitor(AstNetlist* nodep) { iterate(nodep); }
+    virtual ~AssertVisitor() override {
        V3Stats::addStat("Assertions, assert non-immediate statements", m_statAsNotImm);
        V3Stats::addStat("Assertions, assert immediate statements", m_statAsImm);
        V3Stats::addStat("Assertions, cover statements", m_statCover);
@@ -23,9 +23,6 @@
 #include "V3Global.h"
 #include "V3AssertPre.h"

-#include <cstdarg>
-#include <iomanip>
-
 //######################################################################
 // Assert class functions

@@ -37,35 +34,35 @@ private:
    // NODE STATE/TYPES
    // STATE
    // Reset each module:
-    AstNodeSenItem* m_seniDefaultp;  // Default sensitivity (from AstDefClock)
+    AstSenItem* m_seniDefaultp = nullptr;  // Default sensitivity (from AstDefClock)
    // Reset each assertion:
-    AstNodeSenItem* m_senip;  // Last sensitivity
+    AstSenItem* m_senip = nullptr;  // Last sensitivity
    // Reset each always:
-    AstNodeSenItem* m_seniAlwaysp;  // Last sensitivity in always
+    AstSenItem* m_seniAlwaysp = nullptr;  // Last sensitivity in always

    // METHODS
    VL_DEBUG_FUNC;  // Declare debug()

    AstSenTree* newSenTree(AstNode* nodep) {
        // Create sentree based on clocked or default clock
-        // Return NULL for always
-        AstSenTree* newp = NULL;
-        AstNodeSenItem* senip = m_senip;
+        // Return nullptr for always
+        AstSenTree* newp = nullptr;
+        AstSenItem* senip = m_senip;
        if (!senip) senip = m_seniDefaultp;
        if (!senip) senip = m_seniAlwaysp;
        if (!senip) {
-            nodep->v3error("Unsupported: Unclocked assertion");
-            newp = new AstSenTree(nodep->fileline(), NULL);
+            nodep->v3warn(E_UNSUPPORTED, "Unsupported: Unclocked assertion");
+            newp = new AstSenTree(nodep->fileline(), nullptr);
        } else {
            newp = new AstSenTree(nodep->fileline(), senip->cloneTree(true));
        }
        return newp;
    }
-    void clearAssertInfo() { m_senip = NULL; }
+    void clearAssertInfo() { m_senip = nullptr; }

    // VISITORS
    //========== Statements
-    virtual void visit(AstClocking* nodep) VL_OVERRIDE {
+    virtual void visit(AstClocking* nodep) override {
        UINFO(8, "   CLOCKING" << nodep << endl);
        // Store the new default clock, reset on new module
        m_seniDefaultp = nodep->sensesp();
@@ -77,14 +74,14 @@ private:
        }
        VL_DO_DANGLING(pushDeletep(nodep), nodep);
    }
-    virtual void visit(AstAlways* nodep) VL_OVERRIDE {
+    virtual void visit(AstAlways* nodep) override {
        iterateAndNextNull(nodep->sensesp());
        if (nodep->sensesp()) m_seniAlwaysp = nodep->sensesp()->sensesp();
        iterateAndNextNull(nodep->bodysp());
-        m_seniAlwaysp = NULL;
+        m_seniAlwaysp = nullptr;
    }

-    virtual void visit(AstNodeCoverOrAssert* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeCoverOrAssert* nodep) override {
        if (nodep->sentreep()) return;  // Already processed
        clearAssertInfo();
        // Find Clocking's buried under nodep->exprsp
@@ -92,15 +89,59 @@ private:
        if (!nodep->immediate()) nodep->sentreep(newSenTree(nodep));
        clearAssertInfo();
    }
-    virtual void visit(AstPast* nodep) VL_OVERRIDE {
+    virtual void visit(AstFell* nodep) override {
+        if (nodep->sentreep()) return;  // Already processed
+        iterateChildren(nodep);
+        FileLine* fl = nodep->fileline();
+        AstNode* exprp = nodep->exprp()->unlinkFrBack();
+        if (exprp->width() > 1) exprp = new AstSel(fl, exprp, 0, 1);
+        AstNode* past = new AstPast(fl, exprp, nullptr);
+        past->dtypeFrom(exprp);
+        exprp = new AstAnd(fl, past, new AstNot(fl, exprp->cloneTree(false)));
+        exprp->dtypeSetLogicBool();
+        nodep->replaceWith(exprp);
+        nodep->sentreep(newSenTree(nodep));
+        VL_DO_DANGLING(pushDeletep(nodep), nodep);
+    }
+    virtual void visit(AstPast* nodep) override {
        if (nodep->sentreep()) return;  // Already processed
        iterateChildren(nodep);
        nodep->sentreep(newSenTree(nodep));
    }
-    virtual void visit(AstPropClocked* nodep) VL_OVERRIDE {
+    virtual void visit(AstRose* nodep) override {
+        if (nodep->sentreep()) return;  // Already processed
+        iterateChildren(nodep);
+        FileLine* fl = nodep->fileline();
+        AstNode* exprp = nodep->exprp()->unlinkFrBack();
+        if (exprp->width() > 1) exprp = new AstSel(fl, exprp, 0, 1);
+        AstNode* past = new AstPast(fl, exprp, nullptr);
+        past->dtypeFrom(exprp);
+        exprp = new AstAnd(fl, new AstNot(fl, past), exprp->cloneTree(false));
+        exprp->dtypeSetLogicBool();
+        nodep->replaceWith(exprp);
+        nodep->sentreep(newSenTree(nodep));
+        VL_DO_DANGLING(pushDeletep(nodep), nodep);
+    }
+    virtual void visit(AstStable* nodep) override {
+        if (nodep->sentreep()) return;  // Already processed
+        iterateChildren(nodep);
+        FileLine* fl = nodep->fileline();
+        AstNode* exprp = nodep->exprp()->unlinkFrBack();
+        AstNode* past = new AstPast(fl, exprp, nullptr);
+        past->dtypeFrom(exprp);
+        exprp = new AstEq(fl, past,
+                          exprp->cloneTree(false));  // new AstVarRef(fl, exprp, true)
+        exprp->dtypeSetLogicBool();
+        nodep->replaceWith(exprp);
+        nodep->sentreep(newSenTree(nodep));
+        VL_DO_DANGLING(pushDeletep(nodep), nodep);
+    }
+
+    virtual void visit(AstPropClocked* nodep) override {
        // No need to iterate the body, once replace will get iterated
        iterateAndNextNull(nodep->sensesp());
-        if (m_senip) nodep->v3error("Unsupported: Only one PSL clock allowed per assertion");
+        if (m_senip)
+            nodep->v3warn(E_UNSUPPORTED, "Unsupported: Only one PSL clock allowed per assertion");
        // Block is the new expression to evaluate
        AstNode* blockp = nodep->propp()->unlinkFrBack();
        if (nodep->disablep()) {
@@ -119,23 +160,21 @@ private:
        nodep->replaceWith(blockp);
        VL_DO_DANGLING(pushDeletep(nodep), nodep);
    }
-    virtual void visit(AstNodeModule* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeModule* nodep) override {
        iterateChildren(nodep);
        // Reset defaults
-        m_seniDefaultp = NULL;
+        m_seniDefaultp = nullptr;
    }
-    virtual void visit(AstNode* nodep) VL_OVERRIDE { iterateChildren(nodep); }
+    virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }

 public:
    // CONSTRUCTORS
    explicit AssertPreVisitor(AstNetlist* nodep) {
-        m_seniDefaultp = NULL;
-        m_seniAlwaysp = NULL;
        clearAssertInfo();
        // Process
        iterate(nodep);
    }
-    virtual ~AssertPreVisitor() {}
+    virtual ~AssertPreVisitor() override {}
 };

 //######################################################################
@@ -23,7 +23,6 @@
 #include "V3Broken.h"
 #include "V3String.h"

-#include <cstdarg>
 #include <iomanip>
 #include <memory>

@@ -61,17 +60,17 @@ std::ostream& operator<<(std::ostream& os, AstType rhs);

 void AstNode::init() {
    editCountInc();
-    m_fileline = NULL;
-    m_nextp = NULL;
-    m_backp = NULL;
+    m_fileline = nullptr;
+    m_nextp = nullptr;
+    m_backp = nullptr;
    m_headtailp = this;  // When made, we're a list of only a single element
-    m_op1p = NULL;
-    m_op2p = NULL;
-    m_op3p = NULL;
-    m_op4p = NULL;
-    m_iterpp = NULL;
-    m_dtypep = NULL;
-    m_clonep = NULL;
+    m_op1p = nullptr;
+    m_op2p = nullptr;
+    m_op3p = nullptr;
+    m_op4p = nullptr;
+    m_iterpp = nullptr;
+    m_dtypep = nullptr;
+    m_clonep = nullptr;
    m_cloneCnt = 0;
    // Attributes
    m_didWidth = false;
@@ -276,8 +275,8 @@ AstNode* AstNode::addNext(AstNode* nodep, AstNode* newp) {
        // New tail needs the head
        AstNode* newtailp = newp->m_headtailp;
        AstNode* headp = oldtailp->m_headtailp;
-        oldtailp->m_headtailp = NULL;  // May be written again as new head
-        newp->m_headtailp = NULL;  // May be written again as new tail
+        oldtailp->m_headtailp = nullptr;  // May be written again as new head
+        newp->m_headtailp = nullptr;  // May be written again as new tail
        newtailp->m_headtailp = headp;
        headp->m_headtailp = newtailp;
        newp->editCountInc();
@@ -322,17 +321,17 @@ void AstNode::addNextHere(AstNode* newp) {
    //    tail (oldheadtailp && !oldnextp)   // this was tail of list, might also
    //                                     be head of one-node list
    //
-    newp->m_headtailp = NULL;  // Not at head any longer
-    addlastp->m_headtailp = NULL;  // Presume middle of list
+    newp->m_headtailp = nullptr;  // Not at head any longer
+    addlastp->m_headtailp = nullptr;  // Presume middle of list
    // newp might happen to be head/tail after all, if so will be set again below
    if (oldheadtailp) {  // else in middle of list, no change
        if (oldheadtailp == this) {  // this was one node
            this->m_headtailp = addlastp;  // Was head/tail, now a tail
-            addlastp->m_headtailp = oldheadtailp;  // Tail needs to remember head (or NULL)
+            addlastp->m_headtailp = oldheadtailp;  // Tail needs to remember head (or nullptr)
        } else if (!oldnextp) {  // this was tail
-            this->m_headtailp = NULL;  // No longer a tail
+            this->m_headtailp = nullptr;  // No longer a tail
            oldheadtailp->m_headtailp = addlastp;  // Head gets new tail
-            addlastp->m_headtailp = oldheadtailp;  // Tail needs to remember head (or NULL)
+            addlastp->m_headtailp = oldheadtailp;  // Tail needs to remember head (or nullptr)
        }  // else is head, and we're inserting into the middle, so no other change
    }

@@ -471,7 +470,7 @@ AstNode* AstNode::unlinkFrBackWithNext(AstNRelinker* linkerp) {
        }
    }
    if (backp->m_nextp == oldp) {
-        backp->m_nextp = NULL;
+        backp->m_nextp = nullptr;
        // Old list gets truncated
        // New list becomes a list upon itself
        // Most common case is unlinking a entire operand tree
@@ -487,21 +486,21 @@ AstNode* AstNode::unlinkFrBackWithNext(AstNRelinker* linkerp) {
        oldp->m_headtailp = oldtailp;
        oldp->m_headtailp->m_headtailp = oldp;
    } else if (backp->m_op1p == oldp) {
-        backp->m_op1p = NULL;
+        backp->m_op1p = nullptr;
    } else if (backp->m_op2p == oldp) {
-        backp->m_op2p = NULL;
+        backp->m_op2p = nullptr;
    } else if (backp->m_op3p == oldp) {
-        backp->m_op3p = NULL;
+        backp->m_op3p = nullptr;
    } else if (backp->m_op4p == oldp) {
-        backp->m_op4p = NULL;
+        backp->m_op4p = nullptr;
    } else {
        this->v3fatalSrc("Unlink of node with back not pointing to it.");
    }
    // Relink
-    oldp->m_backp = NULL;
+    oldp->m_backp = nullptr;
    // Iterator fixup
-    if (oldp->m_iterpp) *(oldp->m_iterpp) = NULL;
-    oldp->m_iterpp = NULL;
+    if (oldp->m_iterpp) *(oldp->m_iterpp) = nullptr;
+    oldp->m_iterpp = nullptr;
    oldp->debugTreeChange("-unlinkWNextOut: ", __LINE__, true);
    return oldp;
 }
@@ -562,10 +561,10 @@ AstNode* AstNode::unlinkFrBack(AstNRelinker* linkerp) {
    // Iterator fixup
    if (oldp->m_iterpp) *(oldp->m_iterpp) = oldp->m_nextp;
    // Relink
-    oldp->m_nextp = NULL;
-    oldp->m_backp = NULL;
+    oldp->m_nextp = nullptr;
+    oldp->m_backp = nullptr;
    oldp->m_headtailp = this;
-    oldp->m_iterpp = NULL;
+    oldp->m_iterpp = nullptr;
    oldp->debugTreeChange("-unlinkFrBkOut: ", __LINE__, true);
    return oldp;
 }
@@ -599,7 +598,7 @@ void AstNode::relink(AstNRelinker* linkerp) {
    }
    // Relink
    newp->m_backp = backp;
-    linkerp->m_backp = NULL;
+    linkerp->m_backp = nullptr;
    // Iterator fixup
    if (linkerp->m_iterpp) {
        // If we're iterating over a next() link, we need to follow links off the
@@ -611,7 +610,7 @@ void AstNode::relink(AstNRelinker* linkerp) {
        newp->m_iterpp = linkerp->m_iterpp;
    }
    // Empty the linker so not used twice accidentally
-    linkerp->m_backp = NULL;
+    linkerp->m_backp = nullptr;
    this->debugTreeChange("-relinkOut: ", __LINE__, true);
 }

@@ -634,8 +633,8 @@ void AstNode::relinkOneLink(AstNode*& pointpr,  // Ref to pointer that gets set
        newlistlastp->m_nextp = pointpr;
        pointpr->m_backp = newlistlastp;
        // Head/tail
-        pointpr->m_headtailp = NULL;  // Old head
-        newlistlastp->m_headtailp = NULL;  // Old tail
+        pointpr->m_headtailp = nullptr;  // Old head
+        newlistlastp->m_headtailp = nullptr;  // Old tail
        newp->m_headtailp = oldlistlastp;  // Head points to tail
        oldlistlastp->m_headtailp = newp;  // Tail points to head
    }
@@ -669,7 +668,7 @@ AstNode* AstNode::cloneTreeIter() {
    if (this->m_op2p) newp->op2p(this->m_op2p->cloneTreeIterList());
    if (this->m_op3p) newp->op3p(this->m_op3p->cloneTreeIterList());
    if (this->m_op4p) newp->op4p(this->m_op4p->cloneTreeIterList());
-    newp->m_iterpp = NULL;
+    newp->m_iterpp = nullptr;
    newp->clonep(this);  // Save pointers to/from both to simplify relinking.
    this->clonep(newp);  // Save pointers to/from both to simplify relinking.
    return newp;
@@ -677,12 +676,12 @@ AstNode* AstNode::cloneTreeIter() {

 AstNode* AstNode::cloneTreeIterList() {
    // private: Clone list of nodes, set m_headtailp
-    AstNode* newheadp = NULL;
-    AstNode* newtailp = NULL;
-    // Audited to make sure this is never NULL
+    AstNode* newheadp = nullptr;
+    AstNode* newtailp = nullptr;
+    // Audited to make sure this is never nullptr
    for (AstNode* oldp = this; oldp; oldp = oldp->m_nextp) {
        AstNode* newp = oldp->cloneTreeIter();
-        newp->m_headtailp = NULL;
+        newp->m_headtailp = nullptr;
        newp->m_backp = newtailp;
        if (newtailp) newtailp->m_nextp = newp;
        if (!newheadp) newheadp = newp;
@@ -701,10 +700,10 @@ AstNode* AstNode::cloneTree(bool cloneNextLink) {
        newp = cloneTreeIterList();
    } else {
        newp = cloneTreeIter();
-        newp->m_nextp = NULL;
+        newp->m_nextp = nullptr;
        newp->m_headtailp = newp;
    }
-    newp->m_backp = NULL;
+    newp->m_backp = nullptr;
    newp->cloneRelinkTree();
    newp->debugTreeChange("-cloneOut: ", __LINE__, true);
    return newp;
@@ -727,7 +726,7 @@ void AstNode::deleteNode() {
    this->m_op4p = reinterpret_cast<AstNode*>(0x1);
    if (
 #if !defined(VL_DEBUG) || defined(VL_LEAK_CHECKS)
-        1
+        true
 #else
        !v3Global.opt.debugLeak()
 #endif
@@ -740,7 +739,7 @@ void AstNode::deleteNode() {

 void AstNode::deleteTreeIter() {
    // private: Delete list of nodes. Publicly call deleteTree() instead.
-    // Audited to make sure this is never NULL
+    // Audited to make sure this is never nullptr
    for (AstNode *nodep = this, *nnextp; nodep; nodep = nnextp) {
        nnextp = nodep->m_nextp;
        // MUST be depth first!
@@ -748,8 +747,8 @@ void AstNode::deleteTreeIter() {
        if (nodep->m_op2p) nodep->m_op2p->deleteTreeIter();
        if (nodep->m_op3p) nodep->m_op3p->deleteTreeIter();
        if (nodep->m_op4p) nodep->m_op4p->deleteTreeIter();
-        nodep->m_nextp = NULL;
-        nodep->m_backp = NULL;
+        nodep->m_nextp = nullptr;
+        nodep->m_backp = nullptr;
        nodep->deleteNode();
    }
 }
@@ -832,11 +831,11 @@ void AstNode::iterateAndNext(AstNVisitor& v) {
        niterp->m_iterpp = &niterp;
        niterp->accept(v);
        // accept may do a replaceNode and change niterp on us...
-        // niterp maybe NULL, so need cast if printing
+        // niterp maybe nullptr, so need cast if printing
        // if (niterp != nodep) UINFO(1,"iterateAndNext edited "<<cvtToHex(nodep)
        //                             <<" now into "<<cvtToHex(niterp)<<endl);
        if (!niterp) return;  // Perhaps node deleted inside accept
-        niterp->m_iterpp = NULL;
+        niterp->m_iterpp = nullptr;
        if (VL_UNLIKELY(niterp != nodep)) {  // Edited node inside accept
            nodep = niterp;
        } else {  // Unchanged node, just continue loop
@@ -854,7 +853,7 @@ void AstNode::iterateListBackwards(AstNVisitor& v) {
        if (nodep->backp()->m_nextp == nodep) {
            nodep = nodep->backp();
        } else {
-            nodep = NULL;
+            nodep = nullptr;
        }  // else: backp points up the tree.
    }
 }
@@ -901,7 +900,7 @@ AstNode* AstNode::iterateSubtreeReturnEdits(AstNVisitor& v) {
    } else {
        // Use back to determine who's pointing at us (IE assume new node
        // grafts into same place as old one)
-        AstNode** nextnodepp = NULL;
+        AstNode** nextnodepp = nullptr;
        if (this->m_backp->m_op1p == this) {
            nextnodepp = &(this->m_backp->m_op1p);
        } else if (this->m_backp->m_op2p == this) {
@@ -975,9 +974,7 @@ std::ostream& operator<<(std::ostream& os, const V3Hash& rhs) {

 V3Hash::V3Hash(const string& name) {
    uint32_t val = 0;
-    for (string::const_iterator it = name.begin(); it != name.end(); ++it) {
-        val = val * 31 + *it;
-    }
+    for (const auto& c : name) val = val * 31 + c;
    setBoth(1, val);
 }

@@ -1000,7 +997,7 @@ void AstNode::checkTreeIter(AstNode* backp) {

 void AstNode::checkTreeIterList(AstNode* backp) {
    // private: Check a (possible) list of nodes, this is always the head of the list
-    // Audited to make sure this is never NULL
+    // Audited to make sure this is never nullptr
    AstNode* headp = this;
    AstNode* tailp = this;
    for (AstNode* nodep = headp; nodep; nodep = nodep->nextp()) {
@@ -1053,7 +1050,7 @@ void AstNode::checkIter() const {
    if (m_iterpp) {
        dumpPtrs(cout);
        // Perhaps something forgot to clear m_iterpp?
-        this->v3fatalSrc("Iteration link should be NULL");
+        this->v3fatalSrc("Iteration link should be nullptr");
    }
 }

@@ -1109,7 +1106,7 @@ void AstNode::dumpTree(std::ostream& os, const string& indent, int maxDepth) con
 }

 void AstNode::dumpTreeAndNext(std::ostream& os, const string& indent, int maxDepth) const {
-    // Audited to make sure this is never NULL
+    // Audited to make sure this is never nullptr
    for (const AstNode* nodep = this; nodep; nodep = nodep->nextp()) {
        nodep->dumpTree(os, indent, maxDepth);
    }
@@ -1120,7 +1117,7 @@ void AstNode::dumpTreeFile(const string& filename, bool append, bool doDump) {
    if (doDump) {
        {  // Write log & close
            UINFO(2, "Dumping " << filename << endl);
-            const vl_unique_ptr<std::ofstream> logsp(V3File::new_ofstream(filename, append));
+            const std::unique_ptr<std::ofstream> logsp(V3File::new_ofstream(filename, append));
            if (logsp->fail()) v3fatal("Can't write " << filename);
            *logsp << "Verilator Tree Dump (format 0x3900) from <e" << std::dec << editCountLast();
            *logsp << "> to <e" << std::dec << editCountGbl() << ">" << endl;
@@ -1129,6 +1126,7 @@ void AstNode::dumpTreeFile(const string& filename, bool append, bool doDump) {
                *logsp << "No changes since last dump!\n";
            } else {
                dumpTree(*logsp);
+                editCountSetLast();  // Next dump can indicate start from here
            }
        }
    }
@@ -1139,13 +1137,11 @@ void AstNode::dumpTreeFile(const string& filename, bool append, bool doDump) {
        // set by other steps if it is called in the middle of other operations
        if (AstNetlist* netp = VN_CAST(this, Netlist)) V3Broken::brokenAll(netp);
    }
-    // Next dump can indicate start from here
-    editCountSetLast();
 }

 void AstNode::v3errorEndFatal(std::ostringstream& str) const {
    v3errorEnd(str);
-    assert(0);
+    assert(0);  // LCOV_EXCL_LINE
    VL_UNREACHABLE
 }

@@ -1154,10 +1150,10 @@ string AstNode::locationStr() const {
    const AstNode* backp = this;
    int itmax = 10000;  // Max iterations before giving up on location search
    while (backp) {
-        if (--itmax < 0) {
+        if (VL_UNCOVERABLE(--itmax < 0)) {
            // Likely some circular back link, and V3Ast is trying to report a low-level error
            UINFO(1, "Ran out of iterations finding locationStr on " << backp << endl);
-            return "";
+            return "";  // LCOV_EXCL_LINE
        }
        const AstScope* scopep;
        if ((scopep = VN_CAST_CONST(backp, Scope))) {
@@ -1269,8 +1265,6 @@ AstNodeDType* AstNode::findVoidDType() const {
 // AstNVisitor

 void AstNVisitor::doDeletes() {
-    for (std::vector<AstNode*>::iterator it = m_deleteps.begin(); it != m_deleteps.end(); ++it) {
-        (*it)->deleteTree();
-    }
+    for (AstNode* nodep : m_deleteps) nodep->deleteTree();
    m_deleteps.clear();
 }
@@ -22,9 +22,9 @@
 #include "V3Global.h"
 #include "V3Graph.h"
 #include "V3PartitionGraph.h"  // Just for mtask dumping
+#include "V3String.h"
 #include "V3EmitCBase.h"

-#include <cstdarg>
 #include <iomanip>
 #include <vector>

@@ -36,7 +36,7 @@ const char* AstIfaceRefDType::broken() const {
    BROKEN_RTN(m_ifacep && !m_ifacep->brokeExists());
    BROKEN_RTN(m_cellp && !m_cellp->brokeExists());
    BROKEN_RTN(m_modportp && !m_modportp->brokeExists());
-    return NULL;
+    return nullptr;
 }

 AstIface* AstIfaceRefDType::ifaceViaCellp() const {
@@ -46,7 +46,7 @@ AstIface* AstIfaceRefDType::ifaceViaCellp() const {
 const char* AstNodeVarRef::broken() const {
    BROKEN_RTN(m_varScopep && !m_varScopep->brokeExists());
    BROKEN_RTN(m_varp && !m_varp->brokeExists());
-    return NULL;
+    return nullptr;
 }

 void AstNodeVarRef::cloneRelink() {
@@ -74,7 +74,7 @@ void AstNodeUOrStructDType::repairMemberCache() {
 }

 const char* AstNodeUOrStructDType::broken() const {
-    vl_unordered_set<AstMemberDType*> exists;
+    std::unordered_set<AstMemberDType*> exists;
    for (AstMemberDType* itemp = membersp(); itemp; itemp = VN_CAST(itemp->nextp(), MemberDType)) {
        exists.insert(itemp);
    }
@@ -84,7 +84,7 @@ const char* AstNodeUOrStructDType::broken() const {
            return "member broken";
        }
    }
-    return NULL;
+    return nullptr;
 }

 void AstNodeCCall::dump(std::ostream& str) const {
@@ -101,7 +101,7 @@ void AstNodeCCall::cloneRelink() {
 }
 const char* AstNodeCCall::broken() const {
    BROKEN_RTN(m_funcp && !m_funcp->brokeExists());
-    return NULL;
+    return nullptr;
 }
 bool AstNodeCCall::isPure() const { return funcp()->pure(); }
 string AstNodeCCall::hiernameProtect() const {
@@ -212,7 +212,7 @@ AstNodeBiop* AstEqWild::newTyped(FileLine* fl, AstNode* lhsp, AstNode* rhsp) {
 }

 AstExecGraph::AstExecGraph(FileLine* fileline)
-    : AstNode(AstType::atExecGraph, fileline) {
+    : AstNode{AstType::atExecGraph, fileline} {
    m_depGraphp = new V3Graph;
 }
 AstExecGraph::~AstExecGraph() { VL_DO_DANGLING(delete m_depGraphp, m_depGraphp); }
@@ -226,6 +226,36 @@ AstNode* AstInsideRange::newAndFromInside(AstNode* exprp, AstNode* lhsp, AstNode
    return newp;
 }

+AstConst* AstConst::parseParamLiteral(FileLine* fl, const string& literal) {
+    bool success = false;
+    if (literal[0] == '"') {
+        // This is a string
+        string v = literal.substr(1, literal.find('"', 1) - 1);
+        return new AstConst(fl, AstConst::VerilogStringLiteral(), v);
+    } else if (literal.find_first_of(".eEpP") != string::npos) {
+        // This may be a real
+        double v = VString::parseDouble(literal, &success);
+        if (success) return new AstConst(fl, AstConst::RealDouble(), v);
+    }
+    if (!success) {
+        // This is either an integer or an error
+        // We first try to convert it as C literal. If strtol returns
+        // 0 this is either an error or 0 was parsed. But in any case
+        // we will try to parse it as a verilog literal, hence having
+        // the false negative for 0 is okay. If anything remains in
+        // the string after the number, this is invalid C and we try
+        // the Verilog literal parser.
+        char* endp;
+        int v = strtol(literal.c_str(), &endp, 0);
+        if ((v != 0) && (endp[0] == 0)) {  // C literal
+            return new AstConst(fl, AstConst::WidthedValue(), 32, v);
+        } else {  // Try a Verilog literal (fatals if not)
+            return new AstConst(fl, AstConst::StringToParse(), literal.c_str());
+        }
+    }
+    return nullptr;
+}
+
 void AstNetlist::timeprecisionMerge(FileLine*, const VTimescale& value) {
    VTimescale prec = v3Global.opt.timeComputePrec(value);
    if (prec.isNone() || prec == m_timeprecision) {
@@ -282,16 +312,16 @@ string AstVar::verilogKwd() const {

 class AstVar::VlArgTypeRecursed {
 public:
-    string m_oref;  // To output, reference part before name, "&"
-    string m_osuffix;  // To output, suffixed after name, "[3]"
-    string m_oprefix;  // To output, prefixed before name, "Foo_t"
-    void clear() {
-        m_oref.clear();
-        m_osuffix.clear();
-        m_oprefix.clear();
-    }
-    string refParen(const string& name) {
-        return m_oref.empty() ? name : "(" + m_oref + " " + name + ")";
+    bool m_isRef;  // Is it a reference?
+    string m_type;  // The base type, e.g.: "Foo_t"s
+    string m_dims;  // Array dimensions, e.g.: "[3][2][1]"
+    string render(const string& name) const {
+        string out;
+        out += m_type;
+        out += " ";
+        out += m_isRef ? "(&" + name + ")" : name;
+        out += m_dims;
+        return out;
    }
 };

@@ -301,126 +331,86 @@ string AstVar::vlArgType(bool named, bool forReturn, bool forFunc, const string&
    string ostatic;
    if (isStatic() && namespc.empty()) ostatic = "static ";

-    VlArgTypeRecursed info = vlArgTypeRecurse(forFunc, dtypep(), false);
+    VlArgTypeRecursed info = vlArgTypeRecurse(forFunc, dtypep());

    string oname;
    if (named) {
-        oname += " ";
        if (!namespc.empty()) oname += namespc + "::";
        oname += VIdProtect::protectIf(name(), protect());
    }
-    return ostatic + info.m_oprefix + info.refParen(oname) + info.m_osuffix;
+    return ostatic + info.render(oname);
 }

 AstVar::VlArgTypeRecursed AstVar::vlArgTypeRecurse(bool forFunc, const AstNodeDType* dtypep,
-                                                   bool arrayed) const {
+                                                   bool compound) const {
+    VlArgTypeRecursed info;
+    info.m_isRef
+        = isDpiOpenArray() || (forFunc && (isWritable() || direction().isRefOrConstRef()));
+
    dtypep = dtypep->skipRefp();
    if (const AstAssocArrayDType* adtypep = VN_CAST_CONST(dtypep, AssocArrayDType)) {
-        VlArgTypeRecursed key = vlArgTypeRecurse(forFunc, adtypep->keyDTypep(), true);
-        VlArgTypeRecursed sub = vlArgTypeRecurse(forFunc, adtypep->subDTypep(), true);
-        string out = "VlAssocArray<";
-        out += key.m_oprefix;
-        if (!key.m_osuffix.empty() || !key.m_oref.empty()) {
-            out += " " + key.m_osuffix + key.m_oref;
-        }
-        out += ", ";
-        out += sub.m_oprefix;
-        if (!sub.m_osuffix.empty() || !sub.m_oref.empty()) {
-            out += " " + sub.m_osuffix + sub.m_oref;
-        }
-        out += "> ";
-        VlArgTypeRecursed info;
-        info.m_oprefix = out;
-        return info;
+        const VlArgTypeRecursed key = vlArgTypeRecurse(false, adtypep->keyDTypep(), true);
+        const VlArgTypeRecursed val = vlArgTypeRecurse(false, adtypep->subDTypep(), true);
+        info.m_type = "VlAssocArray<" + key.m_type + ", " + val.m_type + ">";
    } else if (const AstDynArrayDType* adtypep = VN_CAST_CONST(dtypep, DynArrayDType)) {
-        VlArgTypeRecursed sub = vlArgTypeRecurse(forFunc, adtypep->subDTypep(), true);
-        string out = "VlQueue<";
-        out += sub.m_oprefix;
-        if (!sub.m_osuffix.empty() || !sub.m_oref.empty()) {
-            out += " " + sub.m_osuffix + sub.m_oref;
-        }
-        out += "> ";
-        VlArgTypeRecursed info;
-        info.m_oprefix = out;
-        return info;
+        const VlArgTypeRecursed sub = vlArgTypeRecurse(false, adtypep->subDTypep(), true);
+        info.m_type = "VlQueue<" + sub.m_type + ">";
    } else if (const AstQueueDType* adtypep = VN_CAST_CONST(dtypep, QueueDType)) {
-        VlArgTypeRecursed sub = vlArgTypeRecurse(forFunc, adtypep->subDTypep(), true);
-        VlArgTypeRecursed info;
-        string out = "VlQueue<" + sub.m_oprefix;
-        if (!sub.m_osuffix.empty() || !sub.m_oref.empty()) {
-            out += " " + sub.m_osuffix + sub.m_oref;
-        }
+        const VlArgTypeRecursed sub = vlArgTypeRecurse(false, adtypep->subDTypep(), true);
+        info.m_type = "VlQueue<" + sub.m_type;
        // + 1 below as VlQueue uses 0 to mean unlimited, 1 to mean size() max is 1
-        if (adtypep->boundp()) out += ", " + cvtToStr(adtypep->boundConst() + 1);
-        out += "> ";
-        info.m_oprefix = out;
-        return info;
+        if (adtypep->boundp()) info.m_type += ", " + cvtToStr(adtypep->boundConst() + 1);
+        info.m_type += ">";
    } else if (const AstClassRefDType* adtypep = VN_CAST_CONST(dtypep, ClassRefDType)) {
-        VlArgTypeRecursed info;
-        info.m_oprefix = "VlClassRef<" + EmitCBaseVisitor::prefixNameProtect(adtypep) + ">";
-        return info;
+        info.m_type = "VlClassRef<" + EmitCBaseVisitor::prefixNameProtect(adtypep) + ">";
    } else if (const AstUnpackArrayDType* adtypep = VN_CAST_CONST(dtypep, UnpackArrayDType)) {
-        VlArgTypeRecursed info = vlArgTypeRecurse(forFunc, adtypep->subDTypep(), arrayed);
-        info.m_osuffix = "[" + cvtToStr(adtypep->declRange().elements()) + "]" + info.m_osuffix;
-        return info;
-    } else if (const AstBasicDType* bdtypep = dtypep->basicp()) {
-        string otype;
-        string oarray;
-        bool strtype = bdtypep->keyword() == AstBasicDTypeKwd::STRING;
-        string bitvec;
-        if (!bdtypep->isOpaque() && !v3Global.opt.protectIds()) {
-            // We don't print msb()/lsb() as multidim packed would require recursion,
-            // and may confuse users as C++ data is stored always with bit 0 used
-            bitvec += "/*" + cvtToStr(dtypep->width() - 1) + ":0*/";
+        if (compound) {
+            v3fatalSrc("Dynamic arrays or queues with unpacked elements are not yet supported");
        }
-        if ((forFunc && isReadOnly()) || bdtypep->keyword() == AstBasicDTypeKwd::CHARPTR
-            || bdtypep->keyword() == AstBasicDTypeKwd::SCOPEPTR)
-            otype += "const ";
+        const VlArgTypeRecursed sub = vlArgTypeRecurse(false, adtypep->subDTypep(), compound);
+        info.m_type = sub.m_type;
+        info.m_dims = "[" + cvtToStr(adtypep->declRange().elements()) + "]" + sub.m_dims;
+    } else if (const AstBasicDType* bdtypep = dtypep->basicp()) {
+        // We don't print msb()/lsb() as multidim packed would require recursion,
+        // and may confuse users as C++ data is stored always with bit 0 used
+        const string bitvec = (!bdtypep->isOpaque() && !v3Global.opt.protectIds())
+                                  ? "/*" + cvtToStr(dtypep->width() - 1) + ":0*/"
+                                  : "";
        if (bdtypep->keyword() == AstBasicDTypeKwd::CHARPTR) {
-            otype += "char*";
+            info.m_type = "const char*";
        } else if (bdtypep->keyword() == AstBasicDTypeKwd::SCOPEPTR) {
-            otype += "VerilatedScope*";
+            info.m_type = "const VerilatedScope*";
        } else if (bdtypep->keyword() == AstBasicDTypeKwd::DOUBLE) {
-            otype += "double";
+            info.m_type = "double";
        } else if (bdtypep->keyword() == AstBasicDTypeKwd::FLOAT) {
-            otype += "float";
-        } else if (strtype) {
-            otype += "std::string";
+            info.m_type = "float";
+        } else if (bdtypep->keyword() == AstBasicDTypeKwd::STRING) {
+            info.m_type = "std::string";
        } else if (dtypep->widthMin() <= 8) {  // Handle unpacked arrays; not bdtypep->width
-            otype += "CData" + bitvec;
+            info.m_type = "CData" + bitvec;
        } else if (dtypep->widthMin() <= 16) {
-            otype += "SData" + bitvec;
+            info.m_type = "SData" + bitvec;
        } else if (dtypep->widthMin() <= VL_IDATASIZE) {
-            otype += "IData" + bitvec;
+            info.m_type = "IData" + bitvec;
        } else if (dtypep->isQuad()) {
-            otype += "QData" + bitvec;
+            info.m_type = "QData" + bitvec;
        } else if (dtypep->isWide()) {
-            if (arrayed) {
-                otype += "VlWide<" + cvtToStr(dtypep->widthWords()) + "> ";
+            if (compound) {
+                info.m_type = "VlWide<" + cvtToStr(dtypep->widthWords()) + "> ";
            } else {
-                otype += "WData" + bitvec;  // []'s added later
-                oarray += "[" + cvtToStr(dtypep->widthWords()) + "]";
+                info.m_type += "WData" + bitvec;  // []'s added later
+                info.m_dims = "[" + cvtToStr(dtypep->widthWords()) + "]";
            }
        }
-
-        string oref;
-        if (isDpiOpenArray()
-            || (forFunc
-                && (isWritable() || direction() == VDirection::REF
-                    || direction() == VDirection::CONSTREF || (strtype && isNonOutput())))) {
-            oref = "&";
-        }
-
-        VlArgTypeRecursed info;
-        info.m_oprefix = otype;
-        info.m_osuffix = oarray;
-        info.m_oref = oref;
-        // UINFO(9, "vlArgRec "<<"oprefix="<<info.m_oprefix<<" osuffix="<<info.m_osuffix
-        //      <<" oref="<<info.m_oref<<" "<<dtypep);
-        return info;
    } else {
        v3fatalSrc("Unknown data type in var type emitter: " << dtypep->prettyName());
    }
+
+    UASSERT_OBJ(!compound || info.m_dims.empty(), this, "Declaring C array inside compound type");
+
+    if (forFunc && isReadOnly() && info.m_isRef) { info.m_type = "const " + info.m_type; }
+
+    return info;
 }

 string AstVar::vlEnumType() const {
@@ -472,29 +462,52 @@ string AstVar::vlEnumDir() const {
    return out;
 }

-string AstVar::vlPropInit() const {
+string AstVar::vlPropDecl(const string& propName) const {
    string out;
-    out = vlEnumType();  // VLVT_UINT32 etc
-    out += ", " + vlEnumDir();  // VLVD_IN etc
-    if (AstBasicDType* bdtypep = basicp()) {
-        out += ", VerilatedVarProps::Packed()";
-        out += ", " + cvtToStr(bdtypep->left()) + ", " + cvtToStr(bdtypep->right());
-    }
-    bool first = true;
-    for (AstNodeDType* dtp = dtypep(); dtp;) {
+
+    std::vector<int> ulims;  // Unpacked dimension limits
+    for (const AstNodeDType* dtp = dtypep(); dtp;) {
        dtp = dtp->skipRefp();  // Skip AstRefDType/AstTypedef, or return same node
-        if (AstNodeArrayDType* adtypep = VN_CAST(dtp, NodeArrayDType)) {
-            if (first) {
-                out += ", VerilatedVarProps::Unpacked()";
-                first = false;
-            }
-            out += ", " + cvtToStr(adtypep->declRange().left()) + ", "
-                   + cvtToStr(adtypep->declRange().right());
+        if (const AstNodeArrayDType* const adtypep = VN_CAST_CONST(dtp, NodeArrayDType)) {
+            ulims.push_back(adtypep->declRange().left());
+            ulims.push_back(adtypep->declRange().right());
            dtp = adtypep->subDTypep();
        } else {
            break;  // AstBasicDType - nothing below
        }
    }
+
+    if (!ulims.empty()) {
+        out += "static const int " + propName + "__ulims[";
+        out += cvtToStr(ulims.size());
+        out += "] = {";
+        auto it = ulims.cbegin();
+        out += cvtToStr(*it);
+        while (++it != ulims.cend()) {
+            out += ", ";
+            out += cvtToStr(*it);
+        }
+        out += "};\n";
+    }
+
+    out += "static const VerilatedVarProps ";
+    out += propName;
+    out += "(";
+    out += vlEnumType();  // VLVT_UINT32 etc
+    out += ", " + vlEnumDir();  // VLVD_IN etc
+    if (const AstBasicDType* const bdtypep = basicp()) {
+        out += ", VerilatedVarProps::Packed()";
+        out += ", " + cvtToStr(bdtypep->left());
+        out += ", " + cvtToStr(bdtypep->right());
+    }
+
+    if (!ulims.empty()) {
+        out += ", VerilatedVarProps::Unpacked()";
+        out += ", " + cvtToStr(ulims.size() / 2);
+        out += ", " + propName + "__ulims";
+    }
+
+    out += ");\n";
    return out;
 }

@@ -513,8 +526,8 @@ string AstVar::cPubArgType(bool named, bool forReturn) const {
    }
    if (isWide()) {
        if (forReturn) {
-            v3error("Unsupported: Public functions with >64 bit outputs; "
-                    "make an output of a public task instead");
+            v3warn(E_UNSUPPORTED, "Unsupported: Public functions with >64 bit outputs; "
+                                  "make an output of a public task instead");
        }
        arg += " (& " + name();
        arg += ")[" + cvtToStr(widthWords()) + "]";
@@ -591,13 +604,13 @@ AstVar* AstVar::scVarRecurse(AstNode* nodep) {
        if (anodep->isSc()) {
            return anodep;
        } else {
-            return NULL;
+            return nullptr;
        }
    } else if (VN_IS(nodep, VarRef)) {
        if (VN_CAST(nodep, VarRef)->varp()->isSc()) {
            return VN_CAST(nodep, VarRef)->varp();
        } else {
-            return NULL;
+            return nullptr;
        }
    } else if (VN_IS(nodep, ArraySel)) {
        if (nodep->op1p()) {
@@ -613,15 +626,13 @@ AstVar* AstVar::scVarRecurse(AstNode* nodep) {
            if (AstVar* p = scVarRecurse(nodep->op4p())) return p;
        }
    }
-    return NULL;
+    return nullptr;
 }

 string AstVar::mtasksString() const {
    std::ostringstream os;
    os << "all: ";
-    for (MTaskIdSet::const_iterator it = m_mtaskIds.begin(); it != m_mtaskIds.end(); ++it) {
-        os << *it << " ";
-    }
+    for (const auto& id : m_mtaskIds) os << id << " ";
    return os.str();
 }

@@ -651,17 +662,17 @@ AstNodeDType* AstNodeDType::dtypeDimensionp(int dimension) {
            if (adtypep->isRanged()) {
                if ((dim++) == dimension) return adtypep;
            }
-            return NULL;
+            return nullptr;
        } else if (AstNodeUOrStructDType* adtypep = VN_CAST(dtypep, NodeUOrStructDType)) {
            if (adtypep->packed()) {
                if ((dim++) == dimension) return adtypep;
            }
-            return NULL;
+            return nullptr;
        }
        // Node no ->next in loop; use continue where necessary
        break;
    }
-    return NULL;
+    return nullptr;
 }

 uint32_t AstNodeDType::arrayUnpackedElements() {
@@ -746,14 +757,21 @@ AstNode* AstArraySel::baseFromp(AstNode* nodep) {
    return nodep;
 }

+const char* AstJumpBlock::broken() const {
+    BROKEN_RTN(!labelp()->brokeExistsBelow());
+    return nullptr;
+}
+void AstJumpBlock::cloneRelink() {
+    if (m_labelp->clonep()) m_labelp = m_labelp->clonep();
+}
+
 const char* AstScope::broken() const {
    BROKEN_RTN(m_aboveScopep && !m_aboveScopep->brokeExists());
    BROKEN_RTN(m_aboveCellp && !m_aboveCellp->brokeExists());
    BROKEN_RTN(!m_modp);
    BROKEN_RTN(m_modp && !m_modp->brokeExists());
-    return NULL;
+    return nullptr;
 }
-
 void AstScope::cloneRelink() {
    if (m_aboveScopep && m_aboveScopep->clonep()) m_aboveScopep->clonep();
    if (m_aboveCellp && m_aboveCellp->clonep()) m_aboveCellp->clonep();
@@ -761,7 +779,6 @@ void AstScope::cloneRelink() {
        static_cast<AstNode*>(m_modp)->clonep();
    }
 }
-
 string AstScope::nameDotless() const {
    string out = shortName();
    string::size_type pos;
@@ -780,7 +797,6 @@ string AstScopeName::scopePrettyNameFormatter(AstText* scopeTextp) const {
    if (out.substr(0, 1) == ".") out.replace(0, 1, "");
    return AstNode::prettyName(out);
 }
-
 string AstScopeName::scopeNameFormatter(AstText* scopeTextp) const {
    string out;
    for (AstText* textp = scopeTextp; textp; textp = VN_CAST(textp->nextp(), Text)) {
@@ -797,28 +813,28 @@ string AstScopeName::scopeNameFormatter(AstText* scopeTextp) const {

 bool AstSenTree::hasClocked() const {
    UASSERT_OBJ(sensesp(), this, "SENTREE without any SENITEMs under it");
-    for (AstNodeSenItem* senp = sensesp(); senp; senp = VN_CAST(senp->nextp(), NodeSenItem)) {
+    for (AstSenItem* senp = sensesp(); senp; senp = VN_CAST(senp->nextp(), SenItem)) {
        if (senp->isClocked()) return true;
    }
    return false;
 }
 bool AstSenTree::hasSettle() const {
    UASSERT_OBJ(sensesp(), this, "SENTREE without any SENITEMs under it");
-    for (AstNodeSenItem* senp = sensesp(); senp; senp = VN_CAST(senp->nextp(), NodeSenItem)) {
+    for (AstSenItem* senp = sensesp(); senp; senp = VN_CAST(senp->nextp(), SenItem)) {
        if (senp->isSettle()) return true;
    }
    return false;
 }
 bool AstSenTree::hasInitial() const {
    UASSERT_OBJ(sensesp(), this, "SENTREE without any SENITEMs under it");
-    for (AstNodeSenItem* senp = sensesp(); senp; senp = VN_CAST(senp->nextp(), NodeSenItem)) {
+    for (AstSenItem* senp = sensesp(); senp; senp = VN_CAST(senp->nextp(), SenItem)) {
        if (senp->isInitial()) return true;
    }
    return false;
 }
 bool AstSenTree::hasCombo() const {
    UASSERT_OBJ(sensesp(), this, "SENTREE without any SENITEMs under it");
-    for (AstNodeSenItem* senp = sensesp(); senp; senp = VN_CAST(senp->nextp(), NodeSenItem)) {
+    for (AstSenItem* senp = sensesp(); senp; senp = VN_CAST(senp->nextp(), SenItem)) {
        if (senp->isCombo()) return true;
    }
    return false;
@@ -828,7 +844,7 @@ void AstTypeTable::clearCache() {
    // When we mass-change widthMin in V3WidthCommit, we need to correct the table.
    // Just clear out the maps; the search functions will be used to rebuild the map
    for (int i = 0; i < static_cast<int>(AstBasicDTypeKwd::_ENUM_MAX); ++i) {
-        m_basicps[i] = NULL;
+        m_basicps[i] = nullptr;
    }
    m_detailedMap.clear();
    // Clear generic()'s so dead detection will work
@@ -886,8 +902,9 @@ AstBasicDType* AstTypeTable::findLogicBitDType(FileLine* fl, AstBasicDTypeKwd kw
    return newp;
 }

-AstBasicDType* AstTypeTable::findLogicBitDType(FileLine* fl, AstBasicDTypeKwd kwd, VNumRange range,
-                                               int widthMin, VSigning numeric) {
+AstBasicDType* AstTypeTable::findLogicBitDType(FileLine* fl, AstBasicDTypeKwd kwd,
+                                               const VNumRange& range, int widthMin,
+                                               VSigning numeric) {
    AstBasicDType* new1p = new AstBasicDType(fl, kwd, numeric, range, widthMin);
    AstBasicDType* newp = findInsertSameDType(new1p);
    if (newp != new1p) {
@@ -902,7 +919,7 @@ AstBasicDType* AstTypeTable::findInsertSameDType(AstBasicDType* nodep) {
    VBasicTypeKey key(nodep->width(), nodep->widthMin(), nodep->numeric(), nodep->keyword(),
                      nodep->nrange());
    DetailedMap& mapr = m_detailedMap;
-    DetailedMap::const_iterator it = mapr.find(key);
+    const auto it = mapr.find(key);
    if (it != mapr.end()) return it->second;
    mapr.insert(make_pair(key, nodep));
    nodep->generic(true);
@@ -977,27 +994,37 @@ void AstWhile::addNextStmt(AstNode* newp, AstNode* belowp) {
 //======================================================================
 // Per-type Debugging

+// Render node address for dumps. By default this is just the address
+// printed as hex, but with --dump-tree-addrids we map addresses to short
+// strings with a bijection to aid human readability. Observe that this might
+// not actually be a unique identifier as the address can get reused after a
+// node has been freed.
+static std::string nodeAddr(const AstNode* nodep) {
+    return v3Global.opt.dumpTreeAddrids() ? v3Global.ptrToId(nodep) : cvtToHex(nodep);
+}
+
 void AstNode::dump(std::ostream& str) const {
    str << typeName() << " "
-        << cvtToHex(this)
-        //<<" "<<cvtToHex(this)->m_backp
+        << nodeAddr(this)
+        //<< " " << nodeAddr(m_backp)
        << " <e" << std::dec << editCount() << ((editCount() >= editCountLast()) ? "#>" : ">")
-        << " {" << fileline()->filenameLetters() << std::dec << fileline()->lastLineno() << "}";
-    if (user1p()) str << " u1=" << cvtToHex(user1p());
-    if (user2p()) str << " u2=" << cvtToHex(user2p());
-    if (user3p()) str << " u3=" << cvtToHex(user3p());
-    if (user4p()) str << " u4=" << cvtToHex(user4p());
-    if (user5p()) str << " u5=" << cvtToHex(user5p());
+        << " {" << fileline()->filenameLetters() << std::dec << fileline()->lastLineno()
+        << fileline()->firstColumnLetters() << "}";
+    if (user1p()) str << " u1=" << nodeAddr(user1p());
+    if (user2p()) str << " u2=" << nodeAddr(user2p());
+    if (user3p()) str << " u3=" << nodeAddr(user3p());
+    if (user4p()) str << " u4=" << nodeAddr(user4p());
+    if (user5p()) str << " u5=" << nodeAddr(user5p());
    if (hasDType()) {
        // Final @ so less likely to by accident read it as a nodep
        if (dtypep() == this) {
            str << " @dt=this@";
        } else {
-            str << " @dt=" << cvtToHex(dtypep()) << "@";
+            str << " @dt=" << nodeAddr(dtypep()) << "@";
        }
        if (AstNodeDType* dtp = dtypep()) { dtp->dumpSmall(str); }
    } else {  // V3Broken will throw an error
-        if (dtypep()) str << " %Error-dtype-exp=null,got=" << cvtToHex(dtypep());
+        if (dtypep()) str << " %Error-dtype-exp=null,got=" << nodeAddr(dtypep());
    }
    if (name() != "") {
        if (VN_IS(this, Const)) {
@@ -1051,10 +1078,12 @@ void AstCellInline::dump(std::ostream& str) const {
 const char* AstClassPackage::broken() const {
    BROKEN_BASE_RTN(AstNodeModule::broken());
    BROKEN_RTN(m_classp && !m_classp->brokeExists());
-    return NULL;
+    return nullptr;
 }
 void AstClass::insertCache(AstNode* nodep) {
-    if (VN_IS(nodep, Var) || VN_IS(nodep, NodeFTask) || VN_IS(nodep, EnumItemRef)) {
+    bool doit = (VN_IS(nodep, Var) || VN_IS(nodep, EnumItemRef)
+                 || (VN_IS(nodep, NodeFTask) && !VN_CAST(nodep, NodeFTask)->isExternProto()));
+    if (doit) {
        if (m_members.find(nodep->name()) != m_members.end()) {
            nodep->v3error("Duplicate declaration of member name: " << nodep->prettyNameQ());
        } else {
@@ -1066,7 +1095,11 @@ void AstClass::repairCache() {
    clearCache();
    for (AstNode* itemp = membersp(); itemp; itemp = itemp->nextp()) { insertCache(itemp); }
 }
-void AstClass::dump(std::ostream& str) const { this->AstNode::dump(str); }
+void AstClass::dump(std::ostream& str) const {
+    this->AstNode::dump(str);
+    if (isExtended()) str << " [EXT]";
+    if (isVirtual()) str << " [VIRT]";
+}
 AstClass* AstClassExtends::classp() const {
    AstClassRefDType* refp = VN_CAST(dtypep(), ClassRefDType);
    UASSERT_OBJ(refp, this, "class extends non-ref");
@@ -1142,6 +1175,15 @@ void AstJumpGo::dump(std::ostream& str) const {
        str << "%Error:UNLINKED";
    }
 }
+void AstJumpLabel::dump(std::ostream& str) const {
+    this->AstNode::dump(str);
+    str << " -> ";
+    if (blockp()) {
+        blockp()->dump(str);
+    } else {
+        str << "%Error:UNLINKED";
+    }
+}
 void AstMemberSel::dump(std::ostream& str) const {
    this->AstNode::dump(str);
    str << " -> ";
@@ -1218,12 +1260,16 @@ void AstRange::dump(std::ostream& str) const {
 }
 void AstRefDType::dump(std::ostream& str) const {
    this->AstNodeDType::dump(str);
-    if (defp()) {
+    if (typedefp() || subDTypep()) {
        static bool s_recursing = false;
        if (!s_recursing) {  // Prevent infinite dump if circular typedefs
            s_recursing = true;
            str << " -> ";
-            defp()->dump(str);
+            if (typedefp()) {
+                typedefp()->dump(str);
+            } else if (subDTypep()) {
+                subDTypep()->dump(str);
+            }
            s_recursing = false;
        }
    } else {
@@ -1239,7 +1285,7 @@ void AstNodeDType::dump(std::ostream& str) const {
    this->AstNode::dump(str);
    if (generic()) str << " [GENERIC]";
    if (AstNodeDType* dtp = virtRefDTypep()) {
-        str << " refdt=" << cvtToHex(dtp);
+        str << " refdt=" << nodeAddr(dtp);
        dtp->dumpSmall(str);
    }
 }
@@ -1384,7 +1430,7 @@ void AstVarScope::dump(std::ostream& str) const {
 }
 void AstVarXRef::dump(std::ostream& str) const {
    this->AstNode::dump(str);
-    if (packagep()) { str << " pkg=" << cvtToHex(packagep()); }
+    if (packagep()) { str << " pkg=" << nodeAddr(packagep()); }
    if (lvalue()) {
        str << " [LV] => ";
    } else {
@@ -1402,7 +1448,7 @@ void AstVarXRef::dump(std::ostream& str) const {
 }
 void AstVarRef::dump(std::ostream& str) const {
    this->AstNode::dump(str);
-    if (packagep()) { str << " pkg=" << cvtToHex(packagep()); }
+    if (packagep()) { str << " pkg=" << nodeAddr(packagep()); }
    if (lvalue()) {
        str << " [LV] => ";
    } else {
@@ -1452,17 +1498,20 @@ void AstParseRef::dump(std::ostream& str) const {
    this->AstNode::dump(str);
    str << " [" << expect().ascii() << "]";
 }
-void AstPackageRef::dump(std::ostream& str) const {
+void AstClassOrPackageRef::dump(std::ostream& str) const {
    this->AstNode::dump(str);
-    if (packagep()) { str << " pkg=" << cvtToHex(packagep()); }
+    if (classOrPackagep()) { str << " cpkg=" << nodeAddr(classOrPackagep()); }
    str << " -> ";
-    if (packagep()) {
-        packagep()->dump(str);
+    if (classOrPackagep()) {
+        classOrPackagep()->dump(str);
    } else {
        str << "UNLINKED";
    }
 }
-void AstDot::dump(std::ostream& str) const { this->AstNode::dump(str); }
+void AstDot::dump(std::ostream& str) const {
+    this->AstNode::dump(str);
+    if (colon()) str << " [::]";
+}
 void AstActive::dump(std::ostream& str) const {
    this->AstNode::dump(str);
    str << " => ";
@@ -1474,7 +1523,7 @@ void AstActive::dump(std::ostream& str) const {
 }
 void AstNodeFTaskRef::dump(std::ostream& str) const {
    this->AstNode::dump(str);
-    if (packagep()) { str << " pkg=" << cvtToHex(packagep()); }
+    if (packagep()) { str << " pkg=" << nodeAddr(packagep()); }
    str << " -> ";
    if (dotted() != "") { str << ".=" << dotted() << " "; }
    if (taskp()) {
@@ -1506,6 +1555,8 @@ void AstBegin::dump(std::ostream& str) const {
 }
 void AstCoverDecl::dump(std::ostream& str) const {
    this->AstNode::dump(str);
+    if (!page().empty()) str << " page=" << page();
+    if (!linescov().empty()) str << " lc=" << linescov();
    if (this->dataDeclNullp()) {
        str << " -> ";
        this->dataDeclNullp()->dump(str);
@@ -30,12 +30,9 @@

 #include "V3Global.h"
 #include "V3Begin.h"
-#include "V3Inst.h"
 #include "V3Ast.h"

 #include <algorithm>
-#include <cstdarg>
-#include <vector>

 //######################################################################

@@ -45,11 +42,10 @@ private:
    // Entire netlist:
    // AstNodeFTask::user1      -> bool, 1=processed
    AstUser1InUse m_inuser1;
-    bool m_anyFuncInBegin;
+    bool m_anyFuncInBegin = false;

 public:
-    BeginState()
-        : m_anyFuncInBegin(false) {}
+    BeginState() {}
    ~BeginState() {}
    void userMarkChanged(AstNode* nodep) {
        nodep->user1(true);
@@ -64,25 +60,24 @@ class BeginVisitor : public AstNVisitor {
 private:
    // STATE
    BeginState* m_statep;  // Current global state
-    AstNodeModule* m_modp;  // Current module
-    AstNodeFTask* m_ftaskp;  // Current function/task
+    AstNodeModule* m_modp = nullptr;  // Current module
+    AstNodeFTask* m_ftaskp = nullptr;  // Current function/task
    string m_namedScope;  // Name of begin blocks above us
    string m_unnamedScope;  // Name of begin blocks, including unnamed blocks
-    int m_ifDepth;  // Current if depth
+    int m_ifDepth = 0;  // Current if depth

    // METHODS
    VL_DEBUG_FUNC;  // Declare debug()

    // VISITORS
-    virtual void visit(AstNodeModule* nodep) VL_OVERRIDE {
-        AstNodeModule* origModp = m_modp;
+    virtual void visit(AstNodeModule* nodep) override {
+        VL_RESTORER(m_modp);
        {
            m_modp = nodep;
            iterateChildren(nodep);
        }
-        m_modp = origModp;
    }
-    virtual void visit(AstNodeFTask* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeFTask* nodep) override {
        UINFO(8, "  " << nodep << endl);
        // Rename it
        if (m_unnamedScope != "") {
@@ -95,19 +90,17 @@ private:
        // naming; so that any begin's inside the function will rename
        // inside the function.
        // Process children
-        string oldScope = m_namedScope;
-        string oldUnnamed = m_unnamedScope;
+        VL_RESTORER(m_namedScope);
+        VL_RESTORER(m_unnamedScope);
        {
            m_namedScope = "";
            m_unnamedScope = "";
            m_ftaskp = nodep;
            iterateChildren(nodep);
-            m_ftaskp = NULL;
+            m_ftaskp = nullptr;
        }
-        m_namedScope = oldScope;
-        m_unnamedScope = oldUnnamed;
    }
-    virtual void visit(AstBegin* nodep) VL_OVERRIDE {
+    virtual void visit(AstBegin* nodep) override {
        // Begin blocks were only useful in variable creation, change names and delete
        UINFO(8, "  " << nodep << endl);
        string oldScope = m_namedScope;
@@ -150,7 +143,7 @@ private:
        m_unnamedScope = oldUnnamed;

        // Cleanup
-        AstNode* addsp = NULL;
+        AstNode* addsp = nullptr;
        if (AstNode* stmtsp = nodep->stmtsp()) {
            stmtsp->unlinkFrBackWithNext();
            if (addsp) {
@@ -166,7 +159,7 @@ private:
        }
        VL_DO_DANGLING(pushDeletep(nodep), nodep);
    }
-    virtual void visit(AstVar* nodep) VL_OVERRIDE {
+    virtual void visit(AstVar* nodep) override {
        if (m_unnamedScope != "") {
            // Rename it
            nodep->name(m_unnamedScope + "__DOT__" + nodep->name());
@@ -180,7 +173,7 @@ private:
            }
        }
    }
-    virtual void visit(AstTypedef* nodep) VL_OVERRIDE {
+    virtual void visit(AstTypedef* nodep) override {
        if (m_unnamedScope != "") {
            // Rename it
            nodep->name(m_unnamedScope + "__DOT__" + nodep->name());
@@ -195,7 +188,7 @@ private:
            }
        }
    }
-    virtual void visit(AstCell* nodep) VL_OVERRIDE {
+    virtual void visit(AstCell* nodep) override {
        UINFO(8, "   CELL " << nodep << endl);
        if (m_namedScope != "") {
            m_statep->userMarkChanged(nodep);
@@ -208,14 +201,14 @@ private:
        }
        iterateChildren(nodep);
    }
-    virtual void visit(AstVarXRef* nodep) VL_OVERRIDE {
+    virtual void visit(AstVarXRef* nodep) override {
        UINFO(9, "   VARXREF " << nodep << endl);
        if (m_namedScope != "" && nodep->inlinedDots() == "") {
            nodep->inlinedDots(m_namedScope);
            UINFO(9, "    rescope to " << nodep << endl);
        }
    }
-    virtual void visit(AstScopeName* nodep) VL_OVERRIDE {
+    virtual void visit(AstScopeName* nodep) override {
        // If there's a %m in the display text, we add a special node that will contain the name()
        // Similar code in V3Inline
        if (nodep->user1SetOnce()) return;  // Don't double-add text's
@@ -228,15 +221,15 @@ private:
        }
        iterateChildren(nodep);
    }
-    virtual void visit(AstCoverDecl* nodep) VL_OVERRIDE {
+    virtual void visit(AstCoverDecl* nodep) override {
        // Don't need to fix path in coverage statements, they're not under
        // any BEGINs, but V3Coverage adds them all under the module itself.
        iterateChildren(nodep);
    }
    // VISITORS - LINT CHECK
-    virtual void visit(AstIf* nodep) VL_OVERRIDE {  // not AstNodeIf; other types not covered
+    virtual void visit(AstIf* nodep) override {  // not AstNodeIf; other types not covered
        // Check IFDEPTH warning - could be in other transform files if desire
-        int prevIfDepth = m_ifDepth;
+        VL_RESTORER(m_ifDepth);
        if (m_ifDepth == -1 || v3Global.opt.ifDepth() < 1) {  // Turned off
        } else if (nodep->uniquePragma() || nodep->unique0Pragma() || nodep->priorityPragma()) {
            m_ifDepth = -1;
@@ -247,20 +240,16 @@ private:
            m_ifDepth = -1;
        }
        iterateChildren(nodep);
-        m_ifDepth = prevIfDepth;
    }
-    virtual void visit(AstNode* nodep) VL_OVERRIDE { iterateChildren(nodep); }
+    virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }

 public:
    // CONSTRUCTORS
-    BeginVisitor(AstNetlist* nodep, BeginState* statep) {
-        m_statep = statep;
-        m_modp = NULL;
-        m_ftaskp = NULL;
-        m_ifDepth = 0;
+    BeginVisitor(AstNetlist* nodep, BeginState* statep)
+        : m_statep{statep} {
        iterate(nodep);
    }
-    virtual ~BeginVisitor() {}
+    virtual ~BeginVisitor() override {}
 };

 //######################################################################
@@ -273,21 +262,21 @@ private:
    //   AstNodeFTask::user1p           // Node replaced, rename it

    // VISITORS
-    virtual void visit(AstNodeFTaskRef* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeFTaskRef* nodep) override {
        if (nodep->taskp()->user1()) {  // It was converted
            UINFO(9, "    relinkFTask " << nodep << endl);
            nodep->name(nodep->taskp()->name());
        }
        iterateChildren(nodep);
    }
-    virtual void visit(AstVarRef* nodep) VL_OVERRIDE {
+    virtual void visit(AstVarRef* nodep) override {
        if (nodep->varp()->user1()) {  // It was converted
            UINFO(9, "    relinVarRef " << nodep << endl);
            nodep->name(nodep->varp()->name());
        }
        iterateChildren(nodep);
    }
-    virtual void visit(AstIfaceRefDType* nodep) VL_OVERRIDE {
+    virtual void visit(AstIfaceRefDType* nodep) override {
        // May have changed cell names
        // TypeTable is always after all modules, so names are stable
        UINFO(8, "   IFACEREFDTYPE " << nodep << endl);
@@ -296,12 +285,12 @@ private:
        iterateChildren(nodep);
    }
    //--------------------
-    virtual void visit(AstNode* nodep) VL_OVERRIDE { iterateChildren(nodep); }
+    virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }

 public:
    // CONSTRUCTORS
    BeginRelinkVisitor(AstNetlist* nodep, BeginState*) { iterate(nodep); }
-    virtual ~BeginRelinkVisitor() {}
+    virtual ~BeginRelinkVisitor() override {}
 };

 //######################################################################
@@ -30,7 +30,6 @@
 #include "V3Branch.h"
 #include "V3Ast.h"

-#include <cstdarg>
 #include <map>

 //######################################################################
@@ -66,10 +65,10 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNodeIf* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeIf* nodep) override {
        UINFO(4, " IF: " << nodep << endl);
-        int lastLikely = m_likely;
-        int lastUnlikely = m_unlikely;
+        VL_RESTORER(m_likely);
+        VL_RESTORER(m_unlikely);
        {
            // Do if
            reset();
@@ -89,28 +88,25 @@ private:
                nodep->branchPred(VBranchPred::BP_UNLIKELY);
            }  // else leave unknown
        }
-        m_likely = lastLikely;
-        m_unlikely = lastUnlikely;
    }
-    virtual void visit(AstNodeCCall* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeCCall* nodep) override {
        checkUnlikely(nodep);
        nodep->funcp()->user1Inc();
        iterateChildren(nodep);
    }
-    virtual void visit(AstCFunc* nodep) VL_OVERRIDE {
+    virtual void visit(AstCFunc* nodep) override {
        checkUnlikely(nodep);
        m_cfuncsp.push_back(nodep);
        iterateChildren(nodep);
    }
-    virtual void visit(AstNode* nodep) VL_OVERRIDE {
+    virtual void visit(AstNode* nodep) override {
        checkUnlikely(nodep);
        iterateChildren(nodep);
    }

    // METHODS
    void calc_tasks() {
-        for (CFuncVec::iterator it = m_cfuncsp.begin(); it != m_cfuncsp.end(); ++it) {
-            AstCFunc* nodep = *it;
+        for (AstCFunc* nodep : m_cfuncsp) {
            if (!nodep->dontInline()) nodep->isInline(true);
        }
    }
@@ -122,7 +118,7 @@ public:
        iterateChildren(nodep);
        calc_tasks();
    }
-    virtual ~BranchVisitor() {}
+    virtual ~BranchVisitor() override {}
 };

 //######################################################################
@@ -32,8 +32,7 @@
 #include "V3AstConstOnly.h"

 #include <algorithm>
-#include <cstdarg>
-#include VL_INCLUDE_UNORDERED_MAP
+#include <unordered_map>

 //######################################################################

@@ -42,7 +41,7 @@ class BrokenTable : public AstNVisitor {
 private:
    // MEMBERS
    //   For each node, we keep if it exists or not.
-    typedef vl_unordered_map<const AstNode*, int> NodeMap;  // Performance matters (when --debug)
+    typedef std::unordered_map<const AstNode*, int> NodeMap;  // Performance matters (when --debug)
    static NodeMap s_nodes;  // Set of all nodes that exist
    // BITMASK
    enum { FLAG_ALLOCATED = 0x01 };  // new() and not delete()ed
@@ -50,12 +49,13 @@ private:
    enum { FLAG_LINKABLE = 0x04 };  // Is in netlist tree, can be linked to
    enum { FLAG_LEAKED = 0x08 };  // Known to have been leaked
    enum { FLAG_UNDER_NOW = 0x10 };  // Is in tree as parent of current node
+
 public:
    // METHODS
    static void deleted(const AstNode* nodep) {
        // Called by operator delete on any node - only if VL_LEAK_CHECKS
        if (debug() >= 9) cout << "-nodeDel:  " << cvtToHex(nodep) << endl;
-        NodeMap::iterator iter = s_nodes.find(nodep);
+        const auto iter = s_nodes.find(nodep);
        UASSERT_OBJ(!(iter == s_nodes.end() || !(iter->second & FLAG_ALLOCATED)),
                    reinterpret_cast<const AstNode*>(nodep),
                    "Deleting AstNode object that was never tracked or already deleted");
@@ -68,7 +68,7 @@ public:
    static void addNewed(const AstNode* nodep) {
        // Called by operator new on any node - only if VL_LEAK_CHECKS
        if (debug() >= 9) cout << "-nodeNew:  " << cvtToHex(nodep) << endl;
-        NodeMap::iterator iter = s_nodes.find(nodep);
+        const auto iter = s_nodes.find(nodep);
        UASSERT_OBJ(!(iter != s_nodes.end() && (iter->second & FLAG_ALLOCATED)), nodep,
                    "Newing AstNode object that is already allocated");
        if (iter == s_nodes.end()) {
@@ -79,7 +79,7 @@ public:
    static void setUnder(const AstNode* nodep, bool flag) {
        // Called by BrokenCheckVisitor when each node entered/exited
        if (!okIfLinkedTo(nodep)) return;
-        NodeMap::iterator iter = s_nodes.find(nodep);
+        const auto iter = s_nodes.find(nodep);
        if (iter != s_nodes.end()) {
            iter->second &= ~FLAG_UNDER_NOW;
            if (flag) iter->second |= FLAG_UNDER_NOW;
@@ -90,7 +90,7 @@ public:
        // cppcheck-suppress knownConditionTrueFalse
        if (!linkable) return;  // save some time, else the map will get huge!
 #endif
-        NodeMap::iterator iter = s_nodes.find(nodep);
+        const auto iter = s_nodes.find(nodep);
        if (VL_UNCOVERABLE(iter == s_nodes.end())) {
 #ifdef VL_LEAK_CHECKS
            nodep->v3fatalSrc("AstNode is in tree, but not allocated");
@@ -114,7 +114,7 @@ public:
        // Some generic node has a pointer to this node.  Is it allocated?
        // Use this when might not be in tree; otherwise use okIfLinkedTo().
 #ifdef VL_LEAK_CHECKS
-        NodeMap::iterator iter = s_nodes.find(nodep);
+        const auto iter = s_nodes.find(nodep);
        if (iter == s_nodes.end()) return false;
        if (!(iter->second & FLAG_ALLOCATED)) return false;
 #endif
@@ -122,7 +122,7 @@ public:
    }
    static bool okIfLinkedTo(const AstNode* nodep) {
        // Some node in tree has a pointer to this node.  Is it kosher?
-        NodeMap::iterator iter = s_nodes.find(nodep);
+        const auto iter = s_nodes.find(nodep);
        if (iter == s_nodes.end()) return false;
 #ifdef VL_LEAK_CHECKS
        if (!(iter->second & FLAG_ALLOCATED)) return false;
@@ -131,10 +131,18 @@ public:
        if (!(iter->second & FLAG_LINKABLE)) return false;
        return true;
    }
+    static bool okIfAbove(const AstNode* nodep) {
+        // Must be linked to and below current node
+        if (!okIfLinkedTo(nodep)) return false;
+        const auto iter = s_nodes.find(nodep);
+        if (iter == s_nodes.end()) return false;
+        if ((iter->second & FLAG_UNDER_NOW)) return false;
+        return true;
+    }
    static bool okIfBelow(const AstNode* nodep) {
        // Must be linked to and below current node
        if (!okIfLinkedTo(nodep)) return false;
-        NodeMap::iterator iter = s_nodes.find(nodep);
+        const auto iter = s_nodes.find(nodep);
        if (iter == s_nodes.end()) return false;
        if (!(iter->second & FLAG_UNDER_NOW)) return false;
        return true;
@@ -142,19 +150,22 @@ public:
    static void prepForTree() {
 #ifndef VL_LEAK_CHECKS
        s_nodes.clear();
-#endif
+#else
        for (NodeMap::iterator it = s_nodes.begin(); it != s_nodes.end(); ++it) {
            it->second &= ~FLAG_IN_TREE;
            it->second &= ~FLAG_LINKABLE;
        }
+#endif
    }
    static void doneWithTree() {
        for (int backs = 0; backs < 2;
             backs++) {  // Those with backp() are probably under one leaking without
            for (NodeMap::iterator it = s_nodes.begin(); it != s_nodes.end(); ++it) {
-                if ((it->second & FLAG_ALLOCATED) && !(it->second & FLAG_IN_TREE)
-                    && !(it->second & FLAG_LEAKED)
-                    && (it->first->backp() ? backs == 1 : backs == 0)) {
+                // LCOV_EXCL_START
+                if (VL_UNCOVERABLE((it->second & FLAG_ALLOCATED) && !(it->second & FLAG_IN_TREE)
+                                   && !(it->second & FLAG_LEAKED)
+                                   && (it->first->backp() ? backs == 1 : backs == 0))) {
+
                    // Use only AstNode::dump instead of the virtual one, as there
                    // may be varp() and other cross links that are bad.
                    if (v3Global.opt.debugCheck()) {
@@ -173,14 +184,14 @@ public:
                    }
                    it->second |= FLAG_LEAKED;
                }
+                // LCOV_EXCL_STOP
            }
        }
    }

-public:
    // CONSTRUCTORS
    BrokenTable() {}
-    virtual ~BrokenTable() {}
+    virtual ~BrokenTable() override {}
 };

 BrokenTable::NodeMap BrokenTable::s_nodes;
@@ -193,6 +204,10 @@ bool AstNode::brokeExistsAbove() const {
    // Called by node->broken() routines to do table lookup
    return BrokenTable::okIfBelow(this);
 }
+bool AstNode::brokeExistsBelow() const {
+    // Called by node->broken() routines to do table lookup
+    return BrokenTable::okIfAbove(this);
+}

 //######################################################################

@@ -208,7 +223,7 @@ private:
        iterateChildrenConst(nodep);
    }
    // VISITORS
-    virtual void visit(AstNode* nodep) VL_OVERRIDE {
+    virtual void visit(AstNode* nodep) override {
        // Process not just iterate
        processAndIterate(nodep);
    }
@@ -216,7 +231,7 @@ private:
 public:
    // CONSTRUCTORS
    explicit BrokenMarkVisitor(AstNetlist* nodep) { iterate(nodep); }
-    virtual ~BrokenMarkVisitor() {}
+    virtual ~BrokenMarkVisitor() override {}
 };

 //######################################################################
@@ -224,7 +239,7 @@ public:

 class BrokenCheckVisitor : public AstNVisitor {
 private:
-    void checkWidthMin(const AstNode* nodep) {
+    static void checkWidthMin(const AstNode* nodep) {
        UASSERT_OBJ(nodep->width() == nodep->widthMin()
                        || v3Global.widthMinUsage() != VWidthMinUsage::MATCHES_WIDTH,
                    nodep, "Width != WidthMin");
@@ -256,14 +271,14 @@ private:
        iterateChildrenConst(nodep);
        BrokenTable::setUnder(nodep, false);
    }
-    virtual void visit(AstNodeAssign* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeAssign* nodep) override {
        processAndIterate(nodep);
        UASSERT_OBJ(!(v3Global.assertDTypesResolved() && nodep->brokeLhsMustBeLvalue()
                      && VN_IS(nodep->lhsp(), NodeVarRef)
                      && !VN_CAST(nodep->lhsp(), NodeVarRef)->lvalue()),
                    nodep, "Assignment LHS is not an lvalue");
    }
-    virtual void visit(AstNode* nodep) VL_OVERRIDE {
+    virtual void visit(AstNode* nodep) override {
        // Process not just iterate
        processAndIterate(nodep);
    }
@@ -271,7 +286,7 @@ private:
 public:
    // CONSTRUCTORS
    explicit BrokenCheckVisitor(AstNetlist* nodep) { iterate(nodep); }
-    virtual ~BrokenCheckVisitor() {}
+    virtual ~BrokenCheckVisitor() override {}
 };

 //######################################################################
@@ -32,10 +32,7 @@
 #include "V3CCtors.h"

 #include <algorithm>
-#include <cmath>
-#include <cstdarg>
 #include <map>
-#include <vector>

 class V3CCtorsVisitor {
 private:
@@ -49,14 +46,13 @@ private:
    int m_funcNum;  // Function number being built

 public:
-    AstCFunc* builtFuncp() const { return m_tlFuncp; }
    void add(AstNode* nodep) {
        if (v3Global.opt.outputSplitCFuncs() && v3Global.opt.outputSplitCFuncs() < m_numStmts) {
-            m_funcp = NULL;
+            m_funcp = nullptr;
        }
        if (!m_funcp) {
            m_funcp = new AstCFunc(m_modp->fileline(), m_basename + "_" + cvtToStr(++m_funcNum),
-                                   NULL, "void");
+                                   nullptr, "void");
            m_funcp->isStatic(false);
            m_funcp->declPrivate(true);
            m_funcp->slow(!VN_IS(m_modp, Class));  // Only classes construct on fast path
@@ -82,7 +78,7 @@ public:
        m_modp = nodep;
        m_numStmts = 0;
        m_funcNum = 0;
-        m_tlFuncp = new AstCFunc(nodep->fileline(), basename, NULL, "void");
+        m_tlFuncp = new AstCFunc(nodep->fileline(), basename, nullptr, "void");
        m_tlFuncp->declPrivate(true);
        m_tlFuncp->isStatic(false);
        m_tlFuncp->slow(!VN_IS(m_modp, Class));  // Only classes construct on fast path
@@ -101,7 +97,7 @@ private:

 void V3CCtors::evalAsserts() {
    AstNodeModule* modp = v3Global.rootp()->modulesp();  // Top module wrapper
-    AstCFunc* funcp = new AstCFunc(modp->fileline(), "_eval_debug_assertions", NULL, "void");
+    AstCFunc* funcp = new AstCFunc(modp->fileline(), "_eval_debug_assertions", nullptr, "void");
    funcp->declPrivate(true);
    funcp->isStatic(false);
    funcp->slow(false);
@@ -146,13 +142,11 @@ void V3CCtors::cctorsAll() {
         modp = VN_CAST(modp->nextp(), NodeModule)) {
        // Process each module in turn
        {
-            AstCFunc* varResetFuncp;
            V3CCtorsVisitor var_reset(
                modp, "_ctor_var_reset",
                (VN_IS(modp, Class) ? EmitCBaseVisitor::symClassVar() : ""),
                (VN_IS(modp, Class) ? "vlSymsp" : ""),
                (VN_IS(modp, Class) ? "if (false && vlSymsp) {}  // Prevent unused\n" : ""));
-            varResetFuncp = var_reset.builtFuncp();

            for (AstNode* np = modp->stmtsp(); np; np = np->nextp()) {
                if (AstVar* varp = VN_CAST(np, Var)) {
@@ -176,10 +170,12 @@ void V3CCtors::cctorsAll() {
                }
            }
        }
-        if (VN_IS(modp, Class)) {
-            AstCFunc* funcp = new AstCFunc(modp->fileline(), "~", NULL, "");
+        if (AstClass* classp = VN_CAST(modp, Class)) {
+            AstCFunc* funcp = new AstCFunc(modp->fileline(), "~", nullptr, "");
            funcp->isDestructor(true);
            funcp->isStatic(false);
+            // If can be referred to by base pointer, need virtual delete
+            funcp->isVirtual(classp->isExtended());
            funcp->slow(false);
            modp->addStmtp(funcp);
        }
@@ -32,7 +32,7 @@
 #include "V3Ast.h"
 #include "V3EmitCBase.h"

-#include VL_INCLUDE_UNORDERED_MAP
+#include <unordered_map>

 //######################################################################

@@ -67,7 +67,7 @@ public:

    // CONSTRUCTORS
    explicit CUseState(AstNodeModule* nodep)
-        : m_modInsertp(nodep) {}
+        : m_modInsertp{nodep} {}
    virtual ~CUseState() {}
    VL_UNCOPYABLE(CUseState);
 };
@@ -78,27 +78,26 @@ public:
 class CUseDTypeVisitor : public AstNVisitor {
    // MEMBERS
    CUseState& m_stater;  // State for inserter
-    bool m_impOnly;  // In details needed only for implementation
+    bool m_impOnly = false;  // In details needed only for implementation
    // METHODS
-    virtual void visit(AstClassRefDType* nodep) VL_OVERRIDE {
+    virtual void visit(AstClassRefDType* nodep) override {
        if (nodep->user2SetOnce()) return;  // Process once
        if (!m_impOnly) m_stater.newUse(nodep, VUseType::INT_FWD_CLASS, nodep->classp()->name());
        // No class.h, it's inside the class package's h file
        m_stater.newUse(nodep, VUseType::IMP_INCLUDE, nodep->classp()->packagep()->name());
        // Need to include extends() when we implement, but no need for pointers to know
-        bool oldImpOnly = m_impOnly;
+        VL_RESTORER(m_impOnly);
        {
            m_impOnly = true;
            iterateChildren(nodep->classp());  // This also gets all extend classes
        }
-        m_impOnly = oldImpOnly;
    }
-    virtual void visit(AstNodeDType* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeDType* nodep) override {
        if (nodep->user2SetOnce()) return;  // Process once
        if (nodep->virtRefDTypep()) iterate(nodep->virtRefDTypep());
        if (nodep->virtRefDType2p()) iterate(nodep->virtRefDType2p());
    }
-    virtual void visit(AstNode* nodep) VL_OVERRIDE {
+    virtual void visit(AstNode* nodep) override {
        if (nodep->user2SetOnce()) return;  // Process once
        if (nodep->dtypep() && !nodep->dtypep()->user2()) iterate(nodep->dtypep());
        iterateChildren(nodep);
@@ -107,11 +106,10 @@ class CUseDTypeVisitor : public AstNVisitor {
 public:
    // CONSTRUCTORS
    explicit CUseDTypeVisitor(AstNodeModule* nodep, CUseState& stater)
-        : m_stater(stater)
-        , m_impOnly(false) {
+        : m_stater(stater) {  // Need () or GCC 4.8 false warning
        iterate(nodep);
    }
-    virtual ~CUseDTypeVisitor() {}
+    virtual ~CUseDTypeVisitor() override {}
    VL_UNCOPYABLE(CUseDTypeVisitor);
 };

@@ -132,7 +130,7 @@ class CUseVisitor : public AstNVisitor {
        }
    }
    void makeVlToString(AstClass* nodep) {
-        AstCFunc* funcp = new AstCFunc(nodep->fileline(), "VL_TO_STRING", NULL, "std::string");
+        AstCFunc* funcp = new AstCFunc(nodep->fileline(), "VL_TO_STRING", nullptr, "std::string");
        funcp->argTypes("const VlClassRef<" + EmitCBaseVisitor::prefixNameProtect(nodep)
                        + ">& obj");
        funcp->isMethod(false);
@@ -145,7 +143,7 @@ class CUseVisitor : public AstNVisitor {
        nodep->addStmtp(funcp);
    }
    void makeToString(AstClass* nodep) {
-        AstCFunc* funcp = new AstCFunc(nodep->fileline(), "to_string", NULL, "std::string");
+        AstCFunc* funcp = new AstCFunc(nodep->fileline(), "to_string", nullptr, "std::string");
        funcp->isConst(true);
        funcp->isStatic(false);
        funcp->protect(false);
@@ -156,7 +154,8 @@ class CUseVisitor : public AstNVisitor {
        nodep->addStmtp(funcp);
    }
    void makeToStringMiddle(AstClass* nodep) {
-        AstCFunc* funcp = new AstCFunc(nodep->fileline(), "to_string_middle", NULL, "std::string");
+        AstCFunc* funcp
+            = new AstCFunc(nodep->fileline(), "to_string_middle", nullptr, "std::string");
        funcp->isConst(true);
        funcp->isStatic(false);
        funcp->protect(false);
@@ -189,7 +188,7 @@ class CUseVisitor : public AstNVisitor {
    }

    // VISITORS
-    virtual void visit(AstNodeModule* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeModule* nodep) override {
        if (v3Global.opt.trace()) {
            AstCUse* usep
                = m_state.newUse(nodep, VUseType::INT_FWD_CLASS, v3Global.opt.traceClassBase());
@@ -203,22 +202,22 @@ class CUseVisitor : public AstNVisitor {
            makeToStringMiddle(classp);
        }
    }
-    virtual void visit(AstNode*) VL_OVERRIDE {}  // All in AstNodeModule
+    virtual void visit(AstNode*) override {}  // All in AstNodeModule

 public:
    // CONSTRUCTORS
    explicit CUseVisitor(AstNodeModule* nodep)
-        : m_state(nodep) {
+        : m_state{nodep} {
        iterate(nodep);
    }
-    virtual ~CUseVisitor() {}
+    virtual ~CUseVisitor() override {}
    VL_UNCOPYABLE(CUseVisitor);
 };

 //######################################################################
 // Class class functions

-void V3CUse::cUseAll(AstNetlist* nodep) {
+void V3CUse::cUseAll() {
    UINFO(2, __FUNCTION__ << ": " << endl);
    // Call visitor separately for each module, so visitor state is cleared
    for (AstNodeModule* modp = v3Global.rootp()->modulesp(); modp;
@@ -27,7 +27,7 @@

 class V3CUse {
 public:
-    static void cUseAll(AstNetlist* nodep);
+    static void cUseAll();
 };

 #endif  // Guard
@@ -43,7 +43,6 @@
 #include "V3Stats.h"

 #include <algorithm>
-#include <cstdarg>

 #define CASE_OVERLAP_WIDTH 16  // Maximum width we can check for overlaps in
 #define CASE_BARF 999999  // Magic width when non-constant
@@ -53,12 +52,13 @@

 class CaseLintVisitor : public AstNVisitor {
 private:
-    AstNodeCase* m_caseExprp;  // Under a CASE value node, if so the relevant case statement
+    AstNodeCase* m_caseExprp
+        = nullptr;  // Under a CASE value node, if so the relevant case statement

    // METHODS
    VL_DEBUG_FUNC;  // Declare debug()

-    virtual void visit(AstNodeCase* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeCase* nodep) override {
        if (VN_IS(nodep, Case) && VN_CAST(nodep, Case)->casex()) {
            nodep->v3warn(CASEX, "Suggest casez (with ?'s) in place of casex (with X's)");
        }
@@ -82,10 +82,10 @@ private:
                 itemp = VN_CAST(itemp->nextp(), CaseItem)) {
                iterateAndNextNull(itemp->condsp());
            }
-            m_caseExprp = NULL;
+            m_caseExprp = nullptr;
        }
    }
-    virtual void visit(AstConst* nodep) VL_OVERRIDE {
+    virtual void visit(AstConst* nodep) override {
        // See also neverItem
        if (m_caseExprp && nodep->num().isFourState()) {
            if (VN_IS(m_caseExprp, GenCase)) {
@@ -96,7 +96,7 @@ private:
            } else if (VN_IS(m_caseExprp, Case)
                       && (VN_CAST(m_caseExprp, Case)->casez()
                           || VN_CAST(m_caseExprp, Case)->caseInside())) {
-                if (nodep->num().isUnknown()) {
+                if (nodep->num().isAnyX()) {
                    nodep->v3warn(CASEWITHX, "Use of x constant in casez statement, "
                                             "(perhaps intended ?/z in constant)");
                }
@@ -106,15 +106,12 @@ private:
            }
        }
    }
-    virtual void visit(AstNode* nodep) VL_OVERRIDE { iterateChildren(nodep); }
+    virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }

 public:
    // CONSTRUCTORS
-    explicit CaseLintVisitor(AstNodeCase* nodep) {
-        m_caseExprp = NULL;
-        iterate(nodep);
-    }
-    virtual ~CaseLintVisitor() {}
+    explicit CaseLintVisitor(AstNodeCase* nodep) { iterate(nodep); }
+    virtual ~CaseLintVisitor() override {}
 };

 //######################################################################
@@ -132,9 +129,9 @@ private:
    VDouble0 m_statCaseSlow;  // Statistic tracking

    // Per-CASE
-    int m_caseWidth;  // Width of valueItems
-    int m_caseItems;  // Number of caseItem unique values
-    bool m_caseNoOverlapsAllCovered;  // Proven to be synopsys parallel_case compliant
+    int m_caseWidth = 0;  // Width of valueItems
+    int m_caseItems = 0;  // Number of caseItem unique values
+    bool m_caseNoOverlapsAllCovered = false;  // Proven to be synopsys parallel_case compliant
    // For each possible value, the case branch we need
    AstNode* m_valueItem[1 << CASE_OVERLAP_WIDTH];

@@ -162,7 +159,7 @@ private:
        }
        UINFO(8, "Simple case statement: " << nodep << endl);
        // Zero list of items for each value
-        for (uint32_t i = 0; i < (1UL << m_caseWidth); ++i) m_valueItem[i] = NULL;
+        for (uint32_t i = 0; i < (1UL << m_caseWidth); ++i) m_valueItem[i] = nullptr;
        // Now pick up the values for each assignment
        // We can cheat and use uint32_t's because we only support narrow case's
        bool bitched = false;
@@ -219,7 +216,7 @@ private:
        }

        // Convert valueItem from AstCaseItem* to the expression
-        // Not done earlier, as we may now have a NULL because it's just a ";" NOP branch
+        // Not done earlier, as we may now have a nullptr because it's just a ";" NOP branch
        for (uint32_t i = 0; i < (1UL << m_caseWidth); ++i) {
            m_valueItem[i] = VN_CAST(m_valueItem[i], CaseItem)->bodysp();
        }
@@ -281,13 +278,13 @@ private:
        //                      IF(msb-1, 01, 00))
        AstNode* cexprp = nodep->exprp()->unlinkFrBack();

-        if (debug() >= 9) {
+        if (debug() >= 9) {  // LCOV_EXCL_START
            for (uint32_t i = 0; i < (1UL << m_caseWidth); ++i) {
                if (AstNode* itemp = m_valueItem[i]) {
                    UINFO(9, "Value " << std::hex << i << " " << itemp << endl);
                }
            }
-        }
+        }  // LCOV_EXCL_STOP

        // Handle any assertions
        replaceCaseParallel(nodep, m_caseNoOverlapsAllCovered);
@@ -325,13 +322,13 @@ private:
                hadDefault = true;
            } else {
                // Expressioned clause
-                AstNode* icondNextp = NULL;
-                AstNode* ifexprp = NULL;  // If expression to test
+                AstNode* icondNextp = nullptr;
+                AstNode* ifexprp = nullptr;  // If expression to test
                for (AstNode* icondp = itemp->condsp(); icondp; icondp = icondNextp) {
                    icondNextp = icondp->nextp();
                    icondp->unlinkFrBack();

-                    AstNode* condp = NULL;  // Default is to use and1p/and2p
+                    AstNode* condp = nullptr;  // Default is to use and1p/and2p
                    AstConst* iconstp = VN_CAST(icondp, Const);
                    if (iconstp && neverItem(nodep, iconstp)) {
                        // X in casez can't ever be executed
@@ -378,8 +375,9 @@ private:
        if (!hadDefault) {
            // If there was no default, add a empty one, this greatly simplifies below code
            // and constant propagation will just eliminate it for us later.
-            nodep->addItemsp(new AstCaseItem(
-                nodep->fileline(), new AstConst(nodep->fileline(), AstConst::LogicTrue()), NULL));
+            nodep->addItemsp(
+                new AstCaseItem(nodep->fileline(),
+                                new AstConst(nodep->fileline(), AstConst::LogicTrue()), nullptr));
        }
        if (debug() >= 9) nodep->dumpTree(cout, "    _comp_COND: ");
        // Now build the IF statement tree
@@ -389,9 +387,9 @@ private:
        // should pull out the most common item from here and instead make
        // it the first IF branch.
        int depth = 0;
-        AstNode* grouprootp = NULL;
-        AstIf* groupnextp = NULL;
-        AstIf* itemnextp = NULL;
+        AstNode* grouprootp = nullptr;
+        AstIf* groupnextp = nullptr;
+        AstIf* itemnextp = nullptr;
        for (AstCaseItem* itemp = nodep->itemsp(); itemp;
             itemp = VN_CAST(itemp->nextp(), CaseItem)) {
            AstNode* istmtsp = itemp->bodysp();  // Maybe null -- no action.
@@ -401,9 +399,9 @@ private:
            {  // Prepare for next group
                if (++depth > CASE_ENCODER_GROUP_DEPTH) depth = 1;
                if (depth == 1) {  // First group or starting new group
-                    itemnextp = NULL;
+                    itemnextp = nullptr;
                    AstIf* newp
-                        = new AstIf(itemp->fileline(), ifexprp->cloneTree(true), NULL, NULL);
+                        = new AstIf(itemp->fileline(), ifexprp->cloneTree(true), nullptr, nullptr);
                    if (groupnextp) {
                        groupnextp->addElsesp(newp);
                    } else {
@@ -423,7 +421,7 @@ private:
                    VL_DO_DANGLING(itemexprp->deleteTree(), itemexprp);
                    itemexprp = new AstConst(itemp->fileline(), AstConst::LogicTrue());
                }
-                AstIf* newp = new AstIf(itemp->fileline(), itemexprp, istmtsp, NULL);
+                AstIf* newp = new AstIf(itemp->fileline(), itemexprp, istmtsp, nullptr);
                if (itemnextp) {
                    itemnextp->addElsesp(newp);
                } else {
@@ -460,7 +458,7 @@ private:
        // Xs in case or casez are impossible due to two state simulations
        if (casep->casex()) {
        } else if (casep->casez() || casep->caseInside()) {
-            if (itemp->num().isUnknown()) return true;
+            if (itemp->num().isAnyX()) return true;
        } else {
            if (itemp->num().isFourState()) return true;
        }
@@ -468,7 +466,7 @@ private:
    }

    // VISITORS
-    virtual void visit(AstCase* nodep) VL_OVERRIDE {
+    virtual void visit(AstCase* nodep) override {
        V3Case::caseLint(nodep);
        iterateChildren(nodep);
        if (debug() >= 9) nodep->dumpTree(cout, " case_old: ");
@@ -483,18 +481,15 @@ private:
        }
    }
    //--------------------
-    virtual void visit(AstNode* nodep) VL_OVERRIDE { iterateChildren(nodep); }
+    virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }

 public:
    // CONSTRUCTORS
    explicit CaseVisitor(AstNetlist* nodep) {
-        m_caseWidth = 0;
-        m_caseItems = 0;
-        m_caseNoOverlapsAllCovered = false;
-        for (uint32_t i = 0; i < (1UL << CASE_OVERLAP_WIDTH); ++i) m_valueItem[i] = NULL;
+        for (uint32_t i = 0; i < (1UL << CASE_OVERLAP_WIDTH); ++i) m_valueItem[i] = nullptr;
        iterate(nodep);
    }
-    virtual ~CaseVisitor() {
+    virtual ~CaseVisitor() override {
        V3Stats::addStat("Optimizations, Cases parallelized", m_statCaseFast);
        V3Stats::addStat("Optimizations, Cases complex", m_statCaseSlow);
    }
@@ -45,7 +45,6 @@
 #include "V3Ast.h"

 #include <algorithm>
-#include <cstdarg>

 //######################################################################
 // Cast state, as a visitor of each AstNode
@@ -110,30 +109,39 @@ private:
    }

    // VISITORS
-    virtual void visit(AstNodeUniop* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeUniop* nodep) override {
        iterateChildren(nodep);
        nodep->user1(nodep->lhsp()->user1());
        if (nodep->sizeMattersLhs()) ensureCast(nodep->lhsp());
    }
-    virtual void visit(AstNodeBiop* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeBiop* nodep) override {
        iterateChildren(nodep);
        nodep->user1(nodep->lhsp()->user1() | nodep->rhsp()->user1());
        if (nodep->sizeMattersLhs()) ensureCast(nodep->lhsp());
        if (nodep->sizeMattersRhs()) ensureCast(nodep->rhsp());
    }
-    virtual void visit(AstNodeTriop* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeTriop* nodep) override {
        iterateChildren(nodep);
        nodep->user1(nodep->lhsp()->user1() | nodep->rhsp()->user1() | nodep->thsp()->user1());
        if (nodep->sizeMattersLhs()) ensureCast(nodep->lhsp());
        if (nodep->sizeMattersRhs()) ensureCast(nodep->rhsp());
        if (nodep->sizeMattersThs()) ensureCast(nodep->thsp());
    }
-    virtual void visit(AstCCast* nodep) VL_OVERRIDE {
+    virtual void visit(AstNodeQuadop* nodep) override {
+        iterateChildren(nodep);
+        nodep->user1(nodep->lhsp()->user1() | nodep->rhsp()->user1() | nodep->thsp()->user1()
+                     | nodep->fhsp()->user1());
+        if (nodep->sizeMattersLhs()) ensureCast(nodep->lhsp());
+        if (nodep->sizeMattersRhs()) ensureCast(nodep->rhsp());
+        if (nodep->sizeMattersThs()) ensureCast(nodep->thsp());
+        if (nodep->sizeMattersFhs()) ensureCast(nodep->fhsp());
+    }
+    virtual void visit(AstCCast* nodep) override {
        iterateChildren(nodep);
        ensureLower32Cast(nodep);
        nodep->user1(1);
    }
-    virtual void visit(AstNegate* nodep) VL_OVERRIDE {
+    virtual void visit(AstNegate* nodep) override {
        iterateChildren(nodep);
        nodep->user1(nodep->lhsp()->user1());
        if (nodep->lhsp()->widthMin() == 1) {
@@ -145,7 +153,7 @@ private:
            ensureCast(nodep->lhsp());
        }
    }
-    virtual void visit(AstVarRef* nodep) VL_OVERRIDE {
+    virtual void visit(AstVarRef* nodep) override {
        if (!nodep->lvalue() && !VN_IS(nodep->backp(), CCast) && VN_IS(nodep->backp(), NodeMath)
            && !VN_IS(nodep->backp(), ArraySel) && nodep->backp()->width()
            && castSize(nodep) != castSize(nodep->varp())) {
@@ -155,7 +163,7 @@ private:
        }
        nodep->user1(1);
    }
-    virtual void visit(AstConst* nodep) VL_OVERRIDE {
+    virtual void visit(AstConst* nodep) override {
        // Constants are of unknown size if smaller than 33 bits, because
        // we're too lazy to wrap every constant in the universe in
        // ((IData)#).
@@ -163,29 +171,29 @@ private:
    }

    // Null dereference protection
-    virtual void visit(AstNullCheck* nodep) VL_OVERRIDE {
+    virtual void visit(AstNullCheck* nodep) override {
        iterateChildren(nodep);
        nodep->user1(nodep->lhsp()->user1());
    }
-    virtual void visit(AstCMethodCall* nodep) VL_OVERRIDE {
+    virtual void visit(AstCMethodCall* nodep) override {
        iterateChildren(nodep);
        ensureNullChecked(nodep->fromp());
    }
-    virtual void visit(AstMemberSel* nodep) VL_OVERRIDE {
+    virtual void visit(AstMemberSel* nodep) override {
        iterateChildren(nodep);
        ensureNullChecked(nodep->fromp());
    }

    // NOPs
-    virtual void visit(AstVar*) VL_OVERRIDE {}
+    virtual void visit(AstVar*) override {}

    //--------------------
-    virtual void visit(AstNode* nodep) VL_OVERRIDE { iterateChildren(nodep); }
+    virtual void visit(AstNode* nodep) override { iterateChildren(nodep); }

 public:
    // CONSTRUCTORS
    explicit CastVisitor(AstNetlist* nodep) { iterate(nodep); }
-    virtual ~CastVisitor() {}
+    virtual ~CastVisitor() override {}
 };

 //######################################################################
--- a/Show More
+++ b/Show More