Add warnings and errors to sim -r with VCD code path#5701
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gussmith23 wants to merge 4 commits intomainfrom
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Add warnings and errors to sim -r with VCD code path#5701gussmith23 wants to merge 4 commits intomainfrom
sim -r with VCD code path#5701gussmith23 wants to merge 4 commits intomainfrom
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(1) no check, (2) check with warning, (3) check with error. Previously the single test was not testing all cases, as it was exiting after the first error.
gussmith23
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sim -r with VCD code path
mmicko
reviewed
Mar 3, 2026
| Const value = builder.build(); | ||
| if (shared->debug) | ||
| log("[%s] get %s: %s\n", hiername(), log_signal(sig), log_signal(value)); | ||
| log("[%s] get %s: %s\n", hiername(), log_signal(sig, true), log_signal(value, true)); |
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is adding true as second parameter for log_signal affecting results log output at all ? since this should affect only constants, if so do you have any example for that ?
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| issue_count++; | ||
| std::string wire_name = scope + "." + RTLIL::unescape_id(wire->name); | ||
| log_warning("Input trace contains undriven signal `%s` (%s); values for this signal are not replayed from FST/VCD input.\n", |
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Too long message and it will repeat if there are multiple signals, maybe add a flag for having undriven signals in file and then just display one more warning at the and with something like Values for mentioned signal(s) are not replayed from FST/VCD input.\n
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We have been inspecting the sharp edges of the
simpass (see #5636). This change makes one of the sharp edges a little more visible: specifically, the behavior around undriven wires.Currently, undriven wires will not be driven when replaying from a VCD, which is different from the behavior when replaying with a YW file. This sharp edge is often avoided entirely as flows will convert undriven wires to
$anyseq, which will be driven during VCD replay. However, if one forgets to do this, they will get unexpected simulation behavior.This change adds a check + an error (downgradeable to a warning, or entirely skippable) for undriven wires, during VCD simulation.
This check is implemented using DriverMap to check for undriven signals. Given that this may not be performant for large designs, we also add a flag to disable the check entirely.