Change Signal.fromList's tail from errorX to error #2620
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This is the commit that originally introduced Sadly the commit message doesn't tell us a whole lot why. |
leonschoorl
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By making the undefined tail of a signal created with fromList into an error instead of errorX, this makes it clear when you're trying use a signal without enough input data. A problem with the errorX was that in certain circumstances it can be turned into a signal full of XException. That can turn into a signal full of undefined BitVectors. And when that is used as the basis for the expected values of a outputVerifierBitVector you end up with a testbench that reports everything is fine for some (possibly big) part of the test. Also add HasCallStack to Signal.fromList to help with tracing this error.
After the provided list runs out, the tail of the signal is an infinite signal filled with error calls. This makes sure that a simulation that happens to not use the values in this signal can still make progress.
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By making the undefined tail of a signal created with
fromListinto anerrorinstead oferrorX, this makes it clear when you're trying use a signal without enough input data.A problem with the
errorXwas that in certain circumstances it can be turned into a signal full of XExceptions. That can turn into a signal full of undefined BitVectors.And when that is used as the basis for the expected values of a
outputVerifierBitVectoryou end up with a testbench that reports everything is fine for some (possibly big) part of the test.Also add HasCallStack to Signal.fromList to help with tracing this error.
This currently fails CI because it exposes the exact problem described above in XpmCdcSingle and XpmCdcArraySingle.
I'm working on fixing those tests.
Still TODO: