* Is NEGATE_EXPR gimple valid for pointer (and offset) types
@ 2021-06-05 22:54 Andrew Pinski
2021-06-06 8:02 ` Richard Biener
0 siblings, 1 reply; 2+ messages in thread
From: Andrew Pinski @ 2021-06-05 22:54 UTC (permalink / raw)
To: GCC Mailing List
While debugging PR 100925, I found that after my match.pd (for
A?CST0:CST1) and phiopt patch to use match-and-simplify, gcc will
produce an negate assignment gimple which has a pointer type (and
offset type). Before we would produce "cond ? -1B : 0B" in this case
but now we produce:
_4 = a_2(D) == 0;
_5 = (void *) _4;
_6 = -_5;
Which I think would be invalid gimple but the verifiers don't say it is.
Should the verifier reject this gimple and similar ones? I am going
to do some simple testing to see what code hits it too.
Thanks,
Andrew Pinski
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: Is NEGATE_EXPR gimple valid for pointer (and offset) types
2021-06-05 22:54 Is NEGATE_EXPR gimple valid for pointer (and offset) types Andrew Pinski
@ 2021-06-06 8:02 ` Richard Biener
0 siblings, 0 replies; 2+ messages in thread
From: Richard Biener @ 2021-06-06 8:02 UTC (permalink / raw)
To: Andrew Pinski, Andrew Pinski via Gcc, GCC Mailing List
On June 6, 2021 12:54:03 AM GMT+02:00, Andrew Pinski via Gcc <gcc@gcc.gnu.org> wrote:
>While debugging PR 100925, I found that after my match.pd (for
>A?CST0:CST1) and phiopt patch to use match-and-simplify, gcc will
>produce an negate assignment gimple which has a pointer type (and
>offset type). Before we would produce "cond ? -1B : 0B" in this case
>but now we produce:
> _4 = a_2(D) == 0;
> _5 = (void *) _4;
> _6 = -_5;
>Which I think would be invalid gimple but the verifiers don't say it
>is.
>Should the verifier reject this gimple and similar ones? I am going
>to do some simple testing to see what code hits it too.
I think this is invalid GIMPLE. We only allow BIT_xxx on pointer types. But digging in history might reveal sth I don't remember...
Richard.
>Thanks,
>Andrew Pinski
^ permalink raw reply [flat|nested] 2+ messages in thread
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