public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
* [Bug tree-optimization/107717] New: [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 @ 2022-11-16 15:13 tnfchris at gcc dot gnu.org 2022-11-16 15:52 ` [Bug tree-optimization/107717] " tnfchris at gcc dot gnu.org ` (4 more replies) 0 siblings, 5 replies; 6+ messages in thread From: tnfchris at gcc dot gnu.org @ 2022-11-16 15:13 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107717 Bug ID: 107717 Summary: [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 Product: gcc Version: 13.0 Status: UNCONFIRMED Keywords: ice-on-valid-code Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: tnfchris at gcc dot gnu.org Target Milestone: --- Target: aarch64* After commit dc95e1e9702f2f6367bbc108c8d01169be1b66d2 (origin/trunk, origin/master, origin/HEAD) Author: Hongyu Wang <hongyu.wang@intel.com> Date: Mon Jan 17 13:01:51 2022 +0800 Optimize VEC_PERM_EXPR with same permutation index and operation The sequence c1 = VEC_PERM_EXPR (a, a, mask) c2 = VEC_PERM_EXPR (b, b, mask) c3 = c1 op c2 can be optimized to c = a op b c3 = VEC_PERM_EXPR (c, c, mask) for all integer vector operation, and float operation with full permutation. gcc/ChangeLog: PR target/98167 * match.pd: New perm + vector op patterns for int and fp vector. gcc/testsuite/ChangeLog: PR target/98167 * gcc.target/i386/pr98167.c: New test. We see various ICEs, an example is void foo(int n, char *restrict out, char *restrict in) { for (int i=n; i-->0; ) { out[i] += in[i]; } } compiled with aarch64-none-linux-gnu -O3 -march=armv8-a+sve2 The problem is that the match.pd pattern as written causes the permute to switch from a single register permute to a two register one. The reason is that when the folded result is expanded in SSA form vec_perm (op @0 @1) (op @0 @1) the result of applying op twice results in two distinct SSA names. This fails because expand_vec_perm_const now tries to use a two operand expansion because there's no easy way to tell that these two operands are the same. If it happens early enough we can CSE the operands, but when this happens after vec_lower it generated something the target does not support. I tried getting expand_vec_perm_const to recognize that they are the same, but that's quite hard. It's best to prevent the generation of the two SSA names to begin with, or add an additional rule for match.pd that's able to CSE this. I'm making this issue because I don't know which approach upstream would like so it's easier to ask first. ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/107717] [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 2022-11-16 15:13 [Bug tree-optimization/107717] New: [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 tnfchris at gcc dot gnu.org @ 2022-11-16 15:52 ` tnfchris at gcc dot gnu.org 2022-11-17 8:08 ` rguenth at gcc dot gnu.org ` (3 subsequent siblings) 4 siblings, 0 replies; 6+ messages in thread From: tnfchris at gcc dot gnu.org @ 2022-11-16 15:52 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107717 Tamar Christina <tnfchris at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Assignee|unassigned at gcc dot gnu.org |tnfchris at gcc dot gnu.org --- Comment #1 from Tamar Christina <tnfchris at gcc dot gnu.org> --- testing a patch. ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/107717] [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 2022-11-16 15:13 [Bug tree-optimization/107717] New: [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 tnfchris at gcc dot gnu.org 2022-11-16 15:52 ` [Bug tree-optimization/107717] " tnfchris at gcc dot gnu.org @ 2022-11-17 8:08 ` rguenth at gcc dot gnu.org 2022-11-17 8:22 ` cvs-commit at gcc dot gnu.org ` (2 subsequent siblings) 4 siblings, 0 replies; 6+ messages in thread From: rguenth at gcc dot gnu.org @ 2022-11-17 8:08 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107717 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Target Milestone|--- |13.0 ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/107717] [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 2022-11-16 15:13 [Bug tree-optimization/107717] New: [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 tnfchris at gcc dot gnu.org 2022-11-16 15:52 ` [Bug tree-optimization/107717] " tnfchris at gcc dot gnu.org 2022-11-17 8:08 ` rguenth at gcc dot gnu.org @ 2022-11-17 8:22 ` cvs-commit at gcc dot gnu.org 2022-11-17 8:29 ` tnfchris at gcc dot gnu.org 2022-11-18 8:24 ` wwwhhhyyy333 at gmail dot com 4 siblings, 0 replies; 6+ messages in thread From: cvs-commit at gcc dot gnu.org @ 2022-11-17 8:22 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107717 --- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Tamar Christina <tnfchris@gcc.gnu.org>: https://gcc.gnu.org/g:cbe313060cdcf1d857d42a9e16a1a03e5ff89fff commit r13-4123-gcbe313060cdcf1d857d42a9e16a1a03e5ff89fff Author: Tamar Christina <tamar.christina@arm.com> Date: Thu Nov 17 08:20:59 2022 +0000 middle-end: ensure that VEC_PERM operands get lowered to the same SSA_NAME. [PR107717] At the moment when the VEC_PERMs generated by this match.pd rule is generated it creates two different SSA_NAMEs for the folded operand. Because of this it the permute switches from a single operand permute to a two operand permute and the target may no longer support a permute for this. This fixes it by ensuring we generate the same SSA_NAME for both operands. gcc/ChangeLog: PR tree-optimization/107717 * match.pd: Ensure same SSA_NAME. gcc/testsuite/ChangeLog: PR tree-optimization/107717 * gcc.target/aarch64/sve2/pr107717.c: New test. ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/107717] [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 2022-11-16 15:13 [Bug tree-optimization/107717] New: [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 tnfchris at gcc dot gnu.org ` (2 preceding siblings ...) 2022-11-17 8:22 ` cvs-commit at gcc dot gnu.org @ 2022-11-17 8:29 ` tnfchris at gcc dot gnu.org 2022-11-18 8:24 ` wwwhhhyyy333 at gmail dot com 4 siblings, 0 replies; 6+ messages in thread From: tnfchris at gcc dot gnu.org @ 2022-11-17 8:29 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107717 Tamar Christina <tnfchris at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution|--- |FIXED --- Comment #3 from Tamar Christina <tnfchris at gcc dot gnu.org> --- Fixed ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug tree-optimization/107717] [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 2022-11-16 15:13 [Bug tree-optimization/107717] New: [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 tnfchris at gcc dot gnu.org ` (3 preceding siblings ...) 2022-11-17 8:29 ` tnfchris at gcc dot gnu.org @ 2022-11-18 8:24 ` wwwhhhyyy333 at gmail dot com 4 siblings, 0 replies; 6+ messages in thread From: wwwhhhyyy333 at gmail dot com @ 2022-11-18 8:24 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107717 --- Comment #4 from Hongyu Wang <wwwhhhyyy333 at gmail dot com> --- (In reply to Tamar Christina from comment #3) > Fixed Thanks for the fix! It also give me a good tip for match pattern writing :) ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-11-18 8:24 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2022-11-16 15:13 [Bug tree-optimization/107717] New: [13 Regression] ICEs expanding permutes after g:dc95e1e9702f2f6367bbc108c8d01169be1b66d2 tnfchris at gcc dot gnu.org 2022-11-16 15:52 ` [Bug tree-optimization/107717] " tnfchris at gcc dot gnu.org 2022-11-17 8:08 ` rguenth at gcc dot gnu.org 2022-11-17 8:22 ` cvs-commit at gcc dot gnu.org 2022-11-17 8:29 ` tnfchris at gcc dot gnu.org 2022-11-18 8:24 ` wwwhhhyyy333 at gmail dot com
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).