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* [Bug target/103548] New: Identical MMA assemble quads are incorrectly combined
@ 2021-12-03 18:52 bergner at gcc dot gnu.org
2021-12-03 19:45 ` [Bug target/103548] " bergner at gcc dot gnu.org
` (5 more replies)
0 siblings, 6 replies; 7+ messages in thread
From: bergner at gcc dot gnu.org @ 2021-12-03 18:52 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103548
Bug ID: 103548
Summary: Identical MMA assemble quads are incorrectly combined
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: bergner at gcc dot gnu.org
Target Milestone: ---
We incorrectly combine multiple identical build/assemble quads/accs leading to
incorrect assembly being generated:
typedef unsigned char vec_t __attribute__((vector_size(16)));
void
foo (__vector_quad *dst, vec_t *src)
{
__vector_quad quad0, quad1;
/* Adjacent loads should be combined into two lxvp instructions.
and identical build accs should not be combined. */
__builtin_mma_build_acc (&quad0, src[0], src[1], src[2], src[3]);
__builtin_mma_build_acc (&quad1, src[0], src[1], src[2], src[3]);
dst[0] = quad0;
dst[2] = quad1;
}
...gives:
lxv 3,0(4)
lxv 2,16(4)
lxv 1,32(4)
lxv 0,48(4)
xxmtacc 0
xxmfacc 0
stxvp 2,0(3)
stxvp 0,32(3)
xxmfacc 0
stxvp 2,128(3)
stxvp 0,160(3)
blr
Notive we only have 4 loads and 1 xxmtacc but 2 xxmfacc. This is incorrect. I
have a patch I'm testing.
Note that for build/assemble pair, we are allowed to combine identical
calls...amd we do.
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/103548] Identical MMA assemble quads are incorrectly combined
2021-12-03 18:52 [Bug target/103548] New: Identical MMA assemble quads are incorrectly combined bergner at gcc dot gnu.org
@ 2021-12-03 19:45 ` bergner at gcc dot gnu.org
2021-12-14 21:00 ` cvs-commit at gcc dot gnu.org
` (4 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: bergner at gcc dot gnu.org @ 2021-12-03 19:45 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103548
Peter Bergner <bergner at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target| |powerpc*-*-*
Assignee|unassigned at gcc dot gnu.org |bergner at gcc dot gnu.org
Target Milestone|--- |12.0
Last reconfirmed| |2021-12-03
Status|UNCONFIRMED |ASSIGNED
Known to fail| |10.0, 11.0, 12.0
Ever confirmed|0 |1
--- Comment #1 from Peter Bergner <bergner at gcc dot gnu.org> ---
Mine.
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/103548] Identical MMA assemble quads are incorrectly combined
2021-12-03 18:52 [Bug target/103548] New: Identical MMA assemble quads are incorrectly combined bergner at gcc dot gnu.org
2021-12-03 19:45 ` [Bug target/103548] " bergner at gcc dot gnu.org
@ 2021-12-14 21:00 ` cvs-commit at gcc dot gnu.org
2021-12-14 23:19 ` bergner at gcc dot gnu.org
` (3 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2021-12-14 21:00 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103548
--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Peter Bergner <bergner@gcc.gnu.org>:
https://gcc.gnu.org/g:15c02ab2569b3c4e27d6f133c013b15a9fa70177
commit r12-5969-g15c02ab2569b3c4e27d6f133c013b15a9fa70177
Author: Peter Bergner <bergner@linux.ibm.com>
Date: Tue Dec 14 14:50:41 2021 -0600
rs6000: Do not allow combining of multiple assemble quads [PR103548]
The compiler will gladly CSE the result of two __builtin_mma_build_acc
calls with the same four vector arguments, leading to illegal MMA
code being generated. The fix here is to make the mma_assemble_acc
pattern use a unspec_volatile to stop the CSE from happening.
2021-12-14 Peter Bergner <bergner@linux.ibm.com>
gcc/
PR target/103548
* config/rs6000/mma.md (UNSPEC_MMA_ASSEMBLE): Rename unspec from
this...
(UNSPEC_VSX_ASSEMBLE): ...to this.
(UNSPECV_MMA_ASSEMBLE): New unspecv.
(vsx_assemble_pair): Use UNSPEC_VSX_ASSEMBLE.
(*vsx_assemble_pair): Likewise.
(mma_assemble_acc): Use UNSPECV_MMA_ASSEMBLE.
(*mma_assemble_acc): Likewise.
* config/rs6000/rs6000.c (rs6000_split_multireg_move): Handle
UNSPEC_VOLATILE. Use UNSPEC_VSX_ASSEMBLE and UNSPECV_MMA_ASSEMBLE.
gcc/testsuite/
PR target/103548
* gcc.target/powerpc/mma-builtin-10-pair.c: New test.
* gcc.target/powerpc/mma-builtin-10-quad.c: New test.
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/103548] Identical MMA assemble quads are incorrectly combined
2021-12-03 18:52 [Bug target/103548] New: Identical MMA assemble quads are incorrectly combined bergner at gcc dot gnu.org
2021-12-03 19:45 ` [Bug target/103548] " bergner at gcc dot gnu.org
2021-12-14 21:00 ` cvs-commit at gcc dot gnu.org
@ 2021-12-14 23:19 ` bergner at gcc dot gnu.org
2022-05-06 8:32 ` jakub at gcc dot gnu.org
` (2 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: bergner at gcc dot gnu.org @ 2021-12-14 23:19 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103548
--- Comment #3 from Peter Bergner <bergner at gcc dot gnu.org> ---
Fixed on trunk. I'll let it bake a couple of days there before backporting to
GCC 11 & 10.
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/103548] Identical MMA assemble quads are incorrectly combined
2021-12-03 18:52 [Bug target/103548] New: Identical MMA assemble quads are incorrectly combined bergner at gcc dot gnu.org
` (2 preceding siblings ...)
2021-12-14 23:19 ` bergner at gcc dot gnu.org
@ 2022-05-06 8:32 ` jakub at gcc dot gnu.org
2023-05-08 12:23 ` rguenth at gcc dot gnu.org
2024-06-20 9:00 ` rguenth at gcc dot gnu.org
5 siblings, 0 replies; 7+ messages in thread
From: jakub at gcc dot gnu.org @ 2022-05-06 8:32 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103548
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|12.0 |12.2
--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
GCC 12.1 is being released, retargeting bugs to GCC 12.2.
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/103548] Identical MMA assemble quads are incorrectly combined
2021-12-03 18:52 [Bug target/103548] New: Identical MMA assemble quads are incorrectly combined bergner at gcc dot gnu.org
` (3 preceding siblings ...)
2022-05-06 8:32 ` jakub at gcc dot gnu.org
@ 2023-05-08 12:23 ` rguenth at gcc dot gnu.org
2024-06-20 9:00 ` rguenth at gcc dot gnu.org
5 siblings, 0 replies; 7+ messages in thread
From: rguenth at gcc dot gnu.org @ 2023-05-08 12:23 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103548
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|12.3 |12.4
--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 12.3 is being released, retargeting bugs to GCC 12.4.
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/103548] Identical MMA assemble quads are incorrectly combined
2021-12-03 18:52 [Bug target/103548] New: Identical MMA assemble quads are incorrectly combined bergner at gcc dot gnu.org
` (4 preceding siblings ...)
2023-05-08 12:23 ` rguenth at gcc dot gnu.org
@ 2024-06-20 9:00 ` rguenth at gcc dot gnu.org
5 siblings, 0 replies; 7+ messages in thread
From: rguenth at gcc dot gnu.org @ 2024-06-20 9:00 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103548
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|12.4 |12.5
--- Comment #7 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] 7+ messages in thread
end of thread, other threads:[~2024-06-20 9:00 UTC | newest]
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2021-12-03 18:52 [Bug target/103548] New: Identical MMA assemble quads are incorrectly combined bergner at gcc dot gnu.org
2021-12-03 19:45 ` [Bug target/103548] " bergner at gcc dot gnu.org
2021-12-14 21:00 ` cvs-commit at gcc dot gnu.org
2021-12-14 23:19 ` bergner at gcc dot gnu.org
2022-05-06 8:32 ` jakub at gcc dot gnu.org
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