public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug middle-end/114669] New: use >= comparison when testing high bits
@ 2024-04-09 22:23 goon.pri.low at gmail dot com
2024-04-09 22:27 ` [Bug tree-optimization/114669] " pinskia at gcc dot gnu.org
2024-04-09 22:36 ` pinskia at gcc dot gnu.org
0 siblings, 2 replies; 3+ messages in thread
From: goon.pri.low at gmail dot com @ 2024-04-09 22:23 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114669
Bug ID: 114669
Summary: use >= comparison when testing high bits
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: goon.pri.low at gmail dot com
Target Milestone: ---
Example C functions
#include <stdint.h>
#include <stdbool.h>
bool unopt(uint32_t x) {
return (x & 0xfff00000) == 0xfff00000;
}
bool opt(uint32_t x) {
return x >= 0xfff00000;
}
Generated assembly
unopt:
not edi
and edi, -1048576
sete al
ret
opt:
cmp edi, -1048577
seta al
ret
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug tree-optimization/114669] use >= comparison when testing high bits
2024-04-09 22:23 [Bug middle-end/114669] New: use >= comparison when testing high bits goon.pri.low at gmail dot com
@ 2024-04-09 22:27 ` pinskia at gcc dot gnu.org
2024-04-09 22:36 ` pinskia at gcc dot gnu.org
1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu.org @ 2024-04-09 22:27 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114669
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Component|middle-end |tree-optimization
CC| |pinskia at gcc dot gnu.org
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
This is almost definitely a dup ...
^ permalink raw reply [flat|nested] 3+ messages in thread
* [Bug tree-optimization/114669] use >= comparison when testing high bits
2024-04-09 22:23 [Bug middle-end/114669] New: use >= comparison when testing high bits goon.pri.low at gmail dot com
2024-04-09 22:27 ` [Bug tree-optimization/114669] " pinskia at gcc dot gnu.org
@ 2024-04-09 22:36 ` pinskia at gcc dot gnu.org
1 sibling, 0 replies; 3+ messages in thread
From: pinskia at gcc dot gnu.org @ 2024-04-09 22:36 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114669
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Severity|normal |enhancement
Last reconfirmed| |2024-04-09
Ever confirmed|0 |1
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2024-04-09 22:36 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-04-09 22:23 [Bug middle-end/114669] New: use >= comparison when testing high bits goon.pri.low at gmail dot com
2024-04-09 22:27 ` [Bug tree-optimization/114669] " pinskia at gcc dot gnu.org
2024-04-09 22:36 ` pinskia at gcc dot gnu.org
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).