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* [Bug tree-optimization/113741] New: missed / wrong optimization switch transformation to same function call @ 2024-02-03 11:04 b.buschinski at googlemail dot com 2024-02-03 11:06 ` [Bug tree-optimization/113741] " sjames at gcc dot gnu.org ` (2 more replies) 0 siblings, 3 replies; 4+ messages in thread From: b.buschinski at googlemail dot com @ 2024-02-03 11:04 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113741 Bug ID: 113741 Summary: missed / wrong optimization switch transformation to same function call Product: gcc Version: 14.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: b.buschinski at googlemail dot com Target Milestone: --- Created attachment 57308 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=57308&action=edit Attached code + asm from the compiler explorer link Compiler Explorer Link: https://godbolt.org/z/KozK9M5YY The code is reduced from a "hot" path with huge macros. I actually improved the macros with adding the "else" in the code, but I noticed it suddenly created even more instructions and got slower. The GCC version has 52 ASM lines. The clang version only 9 ASM lines. Clang is doing a better job here. As far as I understand the ASM code, GCC generates a switch statement, but after the: cmp edi, 5 ja .L11 it should not be needed at all anymore. Additionally, GCC "reloads" the static values again (for every .L*: label) mov edi, 4 , which are already stored in "i" (C code). Tested with GCC-13.2 and compiler explorer gcc "trunk". On x86_64 Linux. Please let me know if you need any additional details or if this report was useful at all. ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug tree-optimization/113741] missed / wrong optimization switch transformation to same function call 2024-02-03 11:04 [Bug tree-optimization/113741] New: missed / wrong optimization switch transformation to same function call b.buschinski at googlemail dot com @ 2024-02-03 11:06 ` sjames at gcc dot gnu.org 2024-02-03 11:10 ` b.buschinski at googlemail dot com 2024-02-03 19:54 ` [Bug tree-optimization/113741] missed " pinskia at gcc dot gnu.org 2 siblings, 0 replies; 4+ messages in thread From: sjames at gcc dot gnu.org @ 2024-02-03 11:06 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113741 Sam James <sjames at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |sjames at gcc dot gnu.org --- Comment #1 from Sam James <sjames at gcc dot gnu.org> --- Note that we reserve the term "wrong" for invalid results or otherwise unsound transformations. ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug tree-optimization/113741] missed / wrong optimization switch transformation to same function call 2024-02-03 11:04 [Bug tree-optimization/113741] New: missed / wrong optimization switch transformation to same function call b.buschinski at googlemail dot com 2024-02-03 11:06 ` [Bug tree-optimization/113741] " sjames at gcc dot gnu.org @ 2024-02-03 11:10 ` b.buschinski at googlemail dot com 2024-02-03 19:54 ` [Bug tree-optimization/113741] missed " pinskia at gcc dot gnu.org 2 siblings, 0 replies; 4+ messages in thread From: b.buschinski at googlemail dot com @ 2024-02-03 11:10 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113741 --- Comment #2 from Bernd Buschinski <b.buschinski at googlemail dot com> --- Ah sorry, I did not know that. Please rephrase the topic to better match the actual problem :) (Or tell me what it should be rephrased to) ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug tree-optimization/113741] missed optimization switch transformation to same function call 2024-02-03 11:04 [Bug tree-optimization/113741] New: missed / wrong optimization switch transformation to same function call b.buschinski at googlemail dot com 2024-02-03 11:06 ` [Bug tree-optimization/113741] " sjames at gcc dot gnu.org 2024-02-03 11:10 ` b.buschinski at googlemail dot com @ 2024-02-03 19:54 ` pinskia at gcc dot gnu.org 2 siblings, 0 replies; 4+ messages in thread From: pinskia at gcc dot gnu.org @ 2024-02-03 19:54 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113741 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution|--- |DUPLICATE --- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Dup of bug 96245. *** This bug has been marked as a duplicate of bug 96245 *** ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2024-02-03 19:54 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2024-02-03 11:04 [Bug tree-optimization/113741] New: missed / wrong optimization switch transformation to same function call b.buschinski at googlemail dot com 2024-02-03 11:06 ` [Bug tree-optimization/113741] " sjames at gcc dot gnu.org 2024-02-03 11:10 ` b.buschinski at googlemail dot com 2024-02-03 19:54 ` [Bug tree-optimization/113741] missed " pinskia at gcc dot gnu.org
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