https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66369
--- Comment #8 from Marcus Kool ---
(In reply to Uroš Bizjak from comment #5)
> Created attachment 35693 [details]
> Patch to add zero-extended MOVMSK patterns
>
> This patch adds zero-extended MOVMSK patterns.
>
> However, one more cast from (
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66369
--- Comment #4 from Marcus Kool ---
> The intrinsic returns "int", and from the above tree dump, the compiler
> won't even consider to combine the sign-extension with vpmovmskb.
>
> So, why not:
>
>unsigned int v;
>
>v = (unsigned int)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66369
--- Comment #3 from Marcus Kool ---
> The intrinsic returns "int", and from the above tree dump, the compiler
> won't even consider to combine the sign-extension with vpmovmskb.
That is the core of the issue: the part of gcc that deals with int
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66369
Marcus Kool changed:
What|Removed |Added
Keywords||missed-optimization
Known to fail|
: c
Assignee: unassigned at gcc dot gnu.org
Reporter: marcus.kool at urlfilterdb dot com
Target Milestone: ---
Created attachment 35672
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35672&action=edit
example C code to demonstrate the missed optimisation in gcc 4.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63791
Marcus Kool changed:
What|Removed |Added
Status|RESOLVED|REOPENED
Resolution|INVALID
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63791
--- Comment #4 from Marcus Kool ---
> movl%edi, -12(%rsp)
> vpxor %xmm1, %xmm1, %xmm1
> vmovd -12(%rsp), %xmm0
> xorl%eax, %eax
> vpshufb %xmm1, %xmm0, %xmm0
The xorl instruction is part of an
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63791
--- Comment #3 from Marcus Kool ---
Created attachment 35436
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35436&action=edit
example code to show code generation on AVX platform (avx.c)
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63791
Marcus Kool changed:
What|Removed |Added
Keywords||missed-optimization
Summary|use
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: marcus.kool at urlfilterdb dot com
Created attachment 33926
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33926&action=edit
code with _mm256_set1_epi8, _mm256_loadu_si256, _mm256_cmpeq_epi8,
_mm256_movema
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