tgt-vvp: Use signedness of expression instead of signal for index load #1166
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When loading a signal into into an index register currently the signedness of the signal is used when deciding whether sign-extension should be performed or not. But this can lead to incorrect results, instead the signedness of the expression must be used as that might be different from the signal. E.g. ``` reg signed [1:0] = 2'b10; $display(1 << x[1:0]); ``` gives the wrong result without this. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Add a regression test to check that the right-hand side of a shift operation is always treated as unsigned, even if it is a signed registers or a variation thereof. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
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martinwhitaker
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Sep 7, 2024
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When loading a signal into into an index register currently the signedness of the signal is used when deciding whether sign-extension should be performed or not. But this can lead to incorrect results, instead the signedness of the expression must be used as that might be different from the signal. E.g.
gives the wrong result without this.
Resolves #1165