public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
* [Bug middle-end/115277] New: ICF needs to match loop bound estimates @ 2024-05-29 14:11 hubicka at gcc dot gnu.org 2024-05-29 14:16 ` [Bug middle-end/115277] [13/14/15 regression] " hubicka at gcc dot gnu.org ` (3 more replies) 0 siblings, 4 replies; 5+ messages in thread From: hubicka at gcc dot gnu.org @ 2024-05-29 14:11 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115277 Bug ID: 115277 Summary: ICF needs to match loop bound estimates Product: gcc Version: 14.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end Assignee: unassigned at gcc dot gnu.org Reporter: hubicka at gcc dot gnu.org Target Milestone: --- jan@localhost:/tmp> cat tt.c int array[1000]; void test (int a) { if (__builtin_expect (a > 3, 1)) return; for (int i = 0; i < a; i++) array[i]=i; } void test2 (int a) { if (__builtin_expect (a > 10, 1)) return; for (int i = 0; i < a; i++) array[i]=i; } int main() { test(1); test(2); test(3); test2(10); if (array[9] != 9) __builtin_abort (); return 0; } jan@localhost:/tmp> gcc -O2 tt.c ; ./a.out jan@localhost:/tmp> gcc -O3 tt.c ; ./a.out Aborted (core dumped) The problem here is that we do not match value ranges and thus we can end up with different estimates on number of iterations. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/115277] [13/14/15 regression] ICF needs to match loop bound estimates 2024-05-29 14:11 [Bug middle-end/115277] New: ICF needs to match loop bound estimates hubicka at gcc dot gnu.org @ 2024-05-29 14:16 ` hubicka at gcc dot gnu.org 2024-05-30 12:53 ` jamborm at gcc dot gnu.org ` (2 subsequent siblings) 3 siblings, 0 replies; 5+ messages in thread From: hubicka at gcc dot gnu.org @ 2024-05-29 14:16 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115277 Jan Hubicka <hubicka at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Summary|ICF needs to match loop |[13/14/15 regression] ICF |bound estimates |needs to match loop bound | |estimates --- Comment #1 from Jan Hubicka <hubicka at gcc dot gnu.org> --- Reproduces on 14 and trunk. GCC 12 is not able to determine the loop bound during early optimizations ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/115277] [13/14/15 regression] ICF needs to match loop bound estimates 2024-05-29 14:11 [Bug middle-end/115277] New: ICF needs to match loop bound estimates hubicka at gcc dot gnu.org 2024-05-29 14:16 ` [Bug middle-end/115277] [13/14/15 regression] " hubicka at gcc dot gnu.org @ 2024-05-30 12:53 ` jamborm at gcc dot gnu.org 2024-05-30 20:36 ` hubicka at ucw dot cz 2024-05-31 6:36 ` rguenth at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: jamborm at gcc dot gnu.org @ 2024-05-30 12:53 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115277 --- Comment #2 from Martin Jambor <jamborm at gcc dot gnu.org> --- (In reply to Jan Hubicka from comment #1) > Reproduces on 14 and trunk. GCC 12 is not able to determine the loop bound > during early optimizations What about gcc 13? ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/115277] [13/14/15 regression] ICF needs to match loop bound estimates 2024-05-29 14:11 [Bug middle-end/115277] New: ICF needs to match loop bound estimates hubicka at gcc dot gnu.org 2024-05-29 14:16 ` [Bug middle-end/115277] [13/14/15 regression] " hubicka at gcc dot gnu.org 2024-05-30 12:53 ` jamborm at gcc dot gnu.org @ 2024-05-30 20:36 ` hubicka at ucw dot cz 2024-05-31 6:36 ` rguenth at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: hubicka at ucw dot cz @ 2024-05-30 20:36 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115277 --- Comment #3 from Jan Hubicka <hubicka at ucw dot cz> --- > What about gcc 13? GCC 13 also misoptimizes. Honza ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/115277] [13/14/15 regression] ICF needs to match loop bound estimates 2024-05-29 14:11 [Bug middle-end/115277] New: ICF needs to match loop bound estimates hubicka at gcc dot gnu.org ` (2 preceding siblings ...) 2024-05-30 20:36 ` hubicka at ucw dot cz @ 2024-05-31 6:36 ` rguenth at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: rguenth at gcc dot gnu.org @ 2024-05-31 6:36 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115277 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Target Milestone|--- |13.4 ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2024-05-31 6:36 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2024-05-29 14:11 [Bug middle-end/115277] New: ICF needs to match loop bound estimates hubicka at gcc dot gnu.org 2024-05-29 14:16 ` [Bug middle-end/115277] [13/14/15 regression] " hubicka at gcc dot gnu.org 2024-05-30 12:53 ` jamborm at gcc dot gnu.org 2024-05-30 20:36 ` hubicka at ucw dot cz 2024-05-31 6:36 ` 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).