Test driver.py: Pass-through +verilator+ arguments to runtime

docs/internals.rst

@@ -2109,6 +2109,14 @@ the regression tests with OBJCACHE enabled and in parallel on a machine
 with many cores.  See the -j option and OBJCACHE environment variable.
 
 
+driver.py Pass-Thru Arguments
+-----------------------------
+
+Arguments not understood by `driver.py` which begin with `+verilator+` are
+passed through as Verilated executable arguments. Other not-understood
+arguments are passed as Verilator arguments.
+
+
 driver.py Non-Scenario Arguments
 --------------------------------
 

test_regress/driver.py

@@ -1543,6 +1543,7 @@ class VlTest:
                 *param['all_run_flags'],
                 ("'" if Args.gdbsim else ""),
             ]
+            cmd += self.driver_verilated_flags
             self.run(
                 cmd=cmd,
                 aslr_off=param['aslr_off'],  # Disable address space layour randomization
@@ -1578,6 +1579,10 @@ class VlTest:
     def driver_verilator_flags(self) -> list:
         return Args.passdown_verilator_flags
 
+    @property
+    def driver_verilated_flags(self) -> list:
+        return Args.passdown_verilated_flags
+
     @property
     def get_default_vltmt_threads(self) -> int:
         return Vltmt_Threads
@@ -2734,6 +2739,8 @@ def _parameter(param: str) -> None:
             sys.exit("%Error: Expected number following " + _Parameter_Next_Level + ": " + param)
         Args.passdown_verilator_flags.append(param)
         _Parameter_Next_Level = None
+    elif re.match(r'^(\+verilator\+.*)', param):
+        Args.passdown_verilated_flags.append(param)
     elif re.search(r'\.py', param):
         Arg_Tests.append(param)
     elif re.match(r'^-?(-debugi|-dumpi)', param):
@@ -2891,6 +2898,7 @@ if __name__ == '__main__':
 
     (Args, rest) = parser.parse_known_intermixed_args()
     Args.passdown_verilator_flags = []
+    Args.passdown_verilated_flags = []
 
     for arg in rest:
         _parameter(arg)