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Re: regrename creates invalid insn
Ian Lance Taylor <iant@google.com> writes:
> Andreas Schwab <schwab@linux-m68k.org> writes:
>
>> Ian Lance Taylor <iant@google.com> writes:
>>
>>> But it also looks like the pattern should use a match_scratch.
>>
>> It is also used as input in operand 2.
>
> Sorry, I missed that.
That appears not to be an issue actually, there is already one use of
match_scratch together with a matching constraint in *cmpdi_internal.
But then, using match_scratch instead of match_operand doesn't really
fix the bug either (it only helps a simplified test case, but not the
original one).
> This still seems like a bug in regrename to me, but it also seems like
> an unusual case, so it is less surprising that it hasn't been seen
> before.
Since regrename is only auto-enabled with -funroll-loops it is probably
not much tested anyway.
Andreas.
--
Andreas Schwab, schwab@linux-m68k.org
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