public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug tree-optimization/115347] New: wrong code at -O3 on x86_64-linux-gnu
@ 2024-06-04 19:13 zhendong.su at inf dot ethz.ch
2024-06-04 20:04 ` [Bug tree-optimization/115347] [12/13/14/15 Regression] " pinskia at gcc dot gnu.org
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: zhendong.su at inf dot ethz.ch @ 2024-06-04 19:13 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115347
Bug ID: 115347
Summary: wrong code at -O3 on x86_64-linux-gnu
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: zhendong.su at inf dot ethz.ch
Target Milestone: ---
It appears to be a regression from 11.*, affecting 12.* and later.
Compiler Explorer: https://godbolt.org/z/PY985hnff
[510] % gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/local/suz-local/software/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/15.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--enable-checking=yes --prefix=/local/suz-local/software/local/gcc-trunk
--enable-sanitizers --enable-languages=c,c++ --disable-werror --enable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 15.0.0 20240604 (experimental) (GCC)
[511] %
[511] % gcctk -O2 small.c; ./a.out
[512] % gcctk -O3 small.c
[513] % ./a.out
Aborted
[514] % cat small.c
struct a {
int b;
int c;
} d, e[2];
int f, g, h;
int main() {
for (; f < 1; f++) {
for (h = 0; h < 2; h++) {
d = e[f];
g = e[1].c;
e[f].c = 1;
}
}
if (d.c != 1)
__builtin_abort();
return 0;
}
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/115347] [12/13/14/15 Regression] wrong code at -O3 on x86_64-linux-gnu
2024-06-04 19:13 [Bug tree-optimization/115347] New: wrong code at -O3 on x86_64-linux-gnu zhendong.su at inf dot ethz.ch
@ 2024-06-04 20:04 ` pinskia at gcc dot gnu.org
2024-06-04 20:09 ` pinskia at gcc dot gnu.org
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu.org @ 2024-06-04 20:04 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115347
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |wrong-code
Summary|wrong code at -O3 on |[12/13/14/15 Regression]
|x86_64-linux-gnu |wrong code at -O3 on
| |x86_64-linux-gnu
Target Milestone|--- |12.4
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/115347] [12/13/14/15 Regression] wrong code at -O3 on x86_64-linux-gnu
2024-06-04 19:13 [Bug tree-optimization/115347] New: wrong code at -O3 on x86_64-linux-gnu zhendong.su at inf dot ethz.ch
2024-06-04 20:04 ` [Bug tree-optimization/115347] [12/13/14/15 Regression] " pinskia at gcc dot gnu.org
@ 2024-06-04 20:09 ` pinskia at gcc dot gnu.org
2024-06-05 7:06 ` rguenth at gcc dot gnu.org
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu.org @ 2024-06-04 20:09 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115347
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |needs-bisection
Last reconfirmed| |2024-06-04
Status|UNCONFIRMED |NEW
Ever confirmed|0 |1
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed.
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/115347] [12/13/14/15 Regression] wrong code at -O3 on x86_64-linux-gnu
2024-06-04 19:13 [Bug tree-optimization/115347] New: wrong code at -O3 on x86_64-linux-gnu zhendong.su at inf dot ethz.ch
2024-06-04 20:04 ` [Bug tree-optimization/115347] [12/13/14/15 Regression] " pinskia at gcc dot gnu.org
2024-06-04 20:09 ` pinskia at gcc dot gnu.org
@ 2024-06-05 7:06 ` rguenth at gcc dot gnu.org
2024-06-17 11:36 ` [Bug tree-optimization/115347] [12/13/14/15 Regression] wrong code at -O3 on x86_64-linux-gnu since r12-2097 jakub at gcc dot gnu.org
2024-06-20 9:15 ` rguenth at gcc dot gnu.org
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu.org @ 2024-06-05 7:06 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115347
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
See Also| |https://gcc.gnu.org/bugzill
| |a/show_bug.cgi?id=112859
Version|unknown |14.1.1
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
it's loop distribution doing
t2.c:7:12: optimized: Loop nest 1 distributed: split to 2 loops and 0 library
calls.
We get
for (; f < 1; f++) {
for (h = 0; h < 2; h++) {
d = e[f];
}
}
for (; f < 1; f++) {
for (h = 0; h < 2; h++) {
g = e[1].c;
e[f].c = 1;
}
}
I think this is similar to the other still open issue where zero-distance
inner loop dependences (&e[f].c doesnt't vary in the inner loop) cause
issues with the interpretation of classical dependence analysis.
I'm somewhat lost there. PR112859.
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/115347] [12/13/14/15 Regression] wrong code at -O3 on x86_64-linux-gnu since r12-2097
2024-06-04 19:13 [Bug tree-optimization/115347] New: wrong code at -O3 on x86_64-linux-gnu zhendong.su at inf dot ethz.ch
` (2 preceding siblings ...)
2024-06-05 7:06 ` rguenth at gcc dot gnu.org
@ 2024-06-17 11:36 ` jakub at gcc dot gnu.org
2024-06-20 9:15 ` rguenth at gcc dot gnu.org
4 siblings, 0 replies; 6+ messages in thread
From: jakub at gcc dot gnu.org @ 2024-06-17 11:36 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115347
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|[12/13/14/15 Regression] |[12/13/14/15 Regression]
|wrong code at -O3 on |wrong code at -O3 on
|x86_64-linux-gnu |x86_64-linux-gnu since
| |r12-2097
Priority|P3 |P2
Keywords|needs-bisection |
CC| |jakub at gcc dot gnu.org
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Started with r12-2097-g9f34b780b0461ec7b2b2defe96e44ab616ea2aa3
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/115347] [12/13/14/15 Regression] wrong code at -O3 on x86_64-linux-gnu since r12-2097
2024-06-04 19:13 [Bug tree-optimization/115347] New: wrong code at -O3 on x86_64-linux-gnu zhendong.su at inf dot ethz.ch
` (3 preceding siblings ...)
2024-06-17 11:36 ` [Bug tree-optimization/115347] [12/13/14/15 Regression] wrong code at -O3 on x86_64-linux-gnu since r12-2097 jakub at gcc dot gnu.org
@ 2024-06-20 9:15 ` rguenth at gcc dot gnu.org
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu.org @ 2024-06-20 9:15 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115347
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|12.4 |12.5
--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 12.4 is being released, retargeting bugs to GCC 12.5.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2024-06-20 9:15 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-06-04 19:13 [Bug tree-optimization/115347] New: wrong code at -O3 on x86_64-linux-gnu zhendong.su at inf dot ethz.ch
2024-06-04 20:04 ` [Bug tree-optimization/115347] [12/13/14/15 Regression] " pinskia at gcc dot gnu.org
2024-06-04 20:09 ` pinskia at gcc dot gnu.org
2024-06-05 7:06 ` rguenth at gcc dot gnu.org
2024-06-17 11:36 ` [Bug tree-optimization/115347] [12/13/14/15 Regression] wrong code at -O3 on x86_64-linux-gnu since r12-2097 jakub at gcc dot gnu.org
2024-06-20 9:15 ` rguenth 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).