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* [Bug target/95235] New: Failure to properly optimize out register use in bit-twiddling code
@ 2020-05-20 9:32 gabravier at gmail dot com
2020-05-20 9:54 ` [Bug target/95235] " rguenth at gcc dot gnu.org
2020-08-10 11:02 ` gabravier at gmail dot com
0 siblings, 2 replies; 3+ messages in thread
From: gabravier at gmail dot com @ 2020-05-20 9:32 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95235
Bug ID: 95235
Summary: Failure to properly optimize out register use in
bit-twiddling code
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: gabravier at gmail dot com
Target Milestone: ---
int f(int a, int b)
{
return ((a & 1) != 0) != (b != 0);
}
With -O3, GCC outputs this :
f(int, int):
test esi, esi
setne al
xor edi, eax
mov eax, edi
and eax, 1
ret
GCC should be able of outputting this instead :
f(int, int):
test esi, esi
setne al
xor eax, edi
and eax, 1
ret
But it does not do so.
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug target/95235] Failure to properly optimize out register use in bit-twiddling code
2020-05-20 9:32 [Bug target/95235] New: Failure to properly optimize out register use in bit-twiddling code gabravier at gmail dot com
@ 2020-05-20 9:54 ` rguenth at gcc dot gnu.org
2020-08-10 11:02 ` gabravier at gmail dot com
1 sibling, 0 replies; 3+ messages in thread
From: rguenth at gcc dot gnu.org @ 2020-05-20 9:54 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95235
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target| |x86_64-*-* i?86-*-*
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
That's indeed odd.
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug target/95235] Failure to properly optimize out register use in bit-twiddling code
2020-05-20 9:32 [Bug target/95235] New: Failure to properly optimize out register use in bit-twiddling code gabravier at gmail dot com
2020-05-20 9:54 ` [Bug target/95235] " rguenth at gcc dot gnu.org
@ 2020-08-10 11:02 ` gabravier at gmail dot com
1 sibling, 0 replies; 3+ messages in thread
From: gabravier at gmail dot com @ 2020-08-10 11:02 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95235
Gabriel Ravier <gabravier at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Resolution|--- |FIXED
Status|UNCONFIRMED |RESOLVED
--- Comment #2 from Gabriel Ravier <gabravier at gmail dot com> ---
Just rechecked and it looks like it was fixed at some point since I filed this
bug report.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2020-08-10 11:02 UTC | newest]
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2020-05-20 9:32 [Bug target/95235] New: Failure to properly optimize out register use in bit-twiddling code gabravier at gmail dot com
2020-05-20 9:54 ` [Bug target/95235] " rguenth at gcc dot gnu.org
2020-08-10 11:02 ` gabravier at gmail dot com
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