public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug fortran/105558] New: simple 8-byte integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions
@ 2022-05-11 7:05 federico.perini at gmail dot com
2022-05-11 7:51 ` [Bug fortran/105558] simple 8-bit " rguenth at gcc dot gnu.org
` (7 more replies)
0 siblings, 8 replies; 9+ messages in thread
From: federico.perini at gmail dot com @ 2022-05-11 7:05 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105558
Bug ID: 105558
Summary: simple 8-byte integer calculation fails with -O3 /
march=core-avx2 on some gfortran 8/9/10 versions
Product: gcc
Version: 10.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: federico.perini at gmail dot com
Target Milestone: ---
Created attachment 52950
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52950&action=edit
integer(1) test program
Hi gcc/gfortran team,
I have two routines that encode and decode two integer(1) IDs (in [1:6] and
[1:32] respectively) to a unique 8-byte integer(1), for 192 possible cases.
The example that fails should behave like
encode(1, 32) returns 77
decode(77) returns [1, 32]
but returns either [-5, 33] or sometimes [3,71]
With -O3, there are both versions and architectures of gfortran that either
work or not. On godbolt (https://godbolt.org/z/5GboahWs1), this is what I see:
gfortran | -O3 -mtune=generic | -O3 -march=core-avx2 |
12.1 | OK | OK |
11.3 | OK | OK |
11.2 | OK | OK |
11.1 | OK | OK |
10.3 | OK | ERROR |
10.2 | OK | ERROR |
10.1 | OK | ERROR |
9.4 | OK | ERROR |
9.3 | OK | ERROR |
9.2 | OK | ERROR |
9.1 | OK | ERROR |
8.5 | ERROR | ERROR |
8.4 | ERROR | ERROR |
8.3 | ERROR | ERROR |
8.2 | ERROR | ERROR |
8.1 | ERROR | ERROR |
7.3 | OK | OK |
7.2 | OK | OK |
7.1 | OK | OK |
6.3 | OK | OK |
5.5 | OK | OK |
Also note that:
- problem is with int8 only; all is OK with int16,int32,int64
- no problems with -O2.
I'm attaching the code here as well,
thank you,
Federico
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug fortran/105558] simple 8-bit integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions
2022-05-11 7:05 [Bug fortran/105558] New: simple 8-byte integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions federico.perini at gmail dot com
@ 2022-05-11 7:51 ` rguenth at gcc dot gnu.org
2022-05-11 8:15 ` federico.perini at gmail dot com
` (6 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: rguenth at gcc dot gnu.org @ 2022-05-11 7:51 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105558
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Last reconfirmed| |2022-05-11
Status|UNCONFIRMED |NEW
Keywords| |needs-bisection
Ever confirmed|0 |1
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Can I ask you to see whether -O3 -fno-tree-vectorize avoids the issue and
whether -O3 -fno-vect-cost-model makes the issue appear in more versions? It
could be that this is a resolved issue that awaits backporting of a fix (or
where backporting is too difficult).
I can confirm the -O3 -march=core-avx2 failure with GCC 10 and success with GCC
11.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug fortran/105558] simple 8-bit integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions
2022-05-11 7:05 [Bug fortran/105558] New: simple 8-byte integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions federico.perini at gmail dot com
2022-05-11 7:51 ` [Bug fortran/105558] simple 8-bit " rguenth at gcc dot gnu.org
@ 2022-05-11 8:15 ` federico.perini at gmail dot com
2022-05-11 8:17 ` federico.perini at gmail dot com
` (5 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: federico.perini at gmail dot com @ 2022-05-11 8:15 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105558
--- Comment #2 from federico <federico.perini at gmail dot com> ---
Ok so we have:
gfortran | [...] -fno-tree-vectorize | [...] -fno-vect-cost-model
10.3 | OK | ERROR
9.3 | OK | ERROR
8.3 | OK | ERROR
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug fortran/105558] simple 8-bit integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions
2022-05-11 7:05 [Bug fortran/105558] New: simple 8-byte integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions federico.perini at gmail dot com
2022-05-11 7:51 ` [Bug fortran/105558] simple 8-bit " rguenth at gcc dot gnu.org
2022-05-11 8:15 ` federico.perini at gmail dot com
@ 2022-05-11 8:17 ` federico.perini at gmail dot com
2022-07-15 10:45 ` marxin at gcc dot gnu.org
` (4 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: federico.perini at gmail dot com @ 2022-05-11 8:17 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105558
--- Comment #3 from federico <federico.perini at gmail dot com> ---
-fno-vect-cost model also does not change behavior on gcc 11/7/6/5 (all OK)
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug fortran/105558] simple 8-bit integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions
2022-05-11 7:05 [Bug fortran/105558] New: simple 8-byte integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions federico.perini at gmail dot com
` (2 preceding siblings ...)
2022-05-11 8:17 ` federico.perini at gmail dot com
@ 2022-07-15 10:45 ` marxin at gcc dot gnu.org
2022-10-27 4:57 ` [Bug tree-optimization/105558] " pinskia at gcc dot gnu.org
` (3 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: marxin at gcc dot gnu.org @ 2022-07-15 10:45 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105558
Martin Liška <marxin at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |marxin at gcc dot gnu.org
Keywords|needs-bisection |
--- Comment #4 from Martin Liška <marxin at gcc dot gnu.org> ---
Fixed on master with r11-3718-g91ae6930ed4a87d7.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/105558] simple 8-bit integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions
2022-05-11 7:05 [Bug fortran/105558] New: simple 8-byte integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions federico.perini at gmail dot com
` (3 preceding siblings ...)
2022-07-15 10:45 ` marxin at gcc dot gnu.org
@ 2022-10-27 4:57 ` pinskia at gcc dot gnu.org
2022-10-27 4:58 ` [Bug tree-optimization/105558] [10 Regression] " pinskia at gcc dot gnu.org
` (2 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: pinskia at gcc dot gnu.org @ 2022-10-27 4:57 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105558
--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Martin Liška from comment #4)
> Fixed on master with r11-3718-g91ae6930ed4a87d7.
If anything that just made the issue latent I suspect.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/105558] [10 Regression] simple 8-bit integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions
2022-05-11 7:05 [Bug fortran/105558] New: simple 8-byte integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions federico.perini at gmail dot com
` (4 preceding siblings ...)
2022-10-27 4:57 ` [Bug tree-optimization/105558] " pinskia at gcc dot gnu.org
@ 2022-10-27 4:58 ` pinskia at gcc dot gnu.org
2023-07-07 10:00 ` [Bug tree-optimization/105558] " rguenth at gcc dot gnu.org
2023-11-07 6:19 ` tkoenig at gcc dot gnu.org
7 siblings, 0 replies; 9+ messages in thread
From: pinskia at gcc dot gnu.org @ 2022-10-27 4:58 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105558
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|simple 8-bit integer |[10 Regression] simple
|calculation fails with -O3 |8-bit integer calculation
|/ march=core-avx2 on some |fails with -O3 /
|gfortran 8/9/10 versions |march=core-avx2 on some
| |gfortran 8/9/10 versions
Known to work| |7.3.0
Known to fail| |8.1.0
Target Milestone|--- |10.5
Keywords| |needs-bisection
--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Would be interesting to find what patch broke this and what patch fixed the
-mtune=generic case.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/105558] simple 8-bit integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions
2022-05-11 7:05 [Bug fortran/105558] New: simple 8-byte integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions federico.perini at gmail dot com
` (5 preceding siblings ...)
2022-10-27 4:58 ` [Bug tree-optimization/105558] [10 Regression] " pinskia at gcc dot gnu.org
@ 2023-07-07 10:00 ` rguenth at gcc dot gnu.org
2023-11-07 6:19 ` tkoenig at gcc dot gnu.org
7 siblings, 0 replies; 9+ messages in thread
From: rguenth at gcc dot gnu.org @ 2023-07-07 10:00 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105558
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|[10 Regression] simple |simple 8-bit integer
|8-bit integer calculation |calculation fails with -O3
|fails with -O3 / |/ march=core-avx2 on some
|march=core-avx2 on some |gfortran 8/9/10 versions
|gfortran 8/9/10 versions |
Known to fail| |10.5.0
Target Milestone|10.5 |---
--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
We don't know the failure mode and the identified fix isn't likely the fix.
Leaving open as non-regression.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/105558] simple 8-bit integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions
2022-05-11 7:05 [Bug fortran/105558] New: simple 8-byte integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions federico.perini at gmail dot com
` (6 preceding siblings ...)
2023-07-07 10:00 ` [Bug tree-optimization/105558] " rguenth at gcc dot gnu.org
@ 2023-11-07 6:19 ` tkoenig at gcc dot gnu.org
7 siblings, 0 replies; 9+ messages in thread
From: tkoenig at gcc dot gnu.org @ 2023-11-07 6:19 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105558
--- Comment #8 from Thomas Koenig <tkoenig at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #6)
> Would be interesting to find what patch broke this and what patch fixed the
> -mtune=generic case.
It is not easy bisecting with old compilers - compilation issues keep
coming up on more modern systems, and sometimes newer compilers do
not compile older compilers...
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2023-11-07 6:19 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-05-11 7:05 [Bug fortran/105558] New: simple 8-byte integer calculation fails with -O3 / march=core-avx2 on some gfortran 8/9/10 versions federico.perini at gmail dot com
2022-05-11 7:51 ` [Bug fortran/105558] simple 8-bit " rguenth at gcc dot gnu.org
2022-05-11 8:15 ` federico.perini at gmail dot com
2022-05-11 8:17 ` federico.perini at gmail dot com
2022-07-15 10:45 ` marxin at gcc dot gnu.org
2022-10-27 4:57 ` [Bug tree-optimization/105558] " pinskia at gcc dot gnu.org
2022-10-27 4:58 ` [Bug tree-optimization/105558] [10 Regression] " pinskia at gcc dot gnu.org
2023-07-07 10:00 ` [Bug tree-optimization/105558] " rguenth at gcc dot gnu.org
2023-11-07 6:19 ` tkoenig 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).