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* [Bug rtl-optimization/57968] New: MODE_EXIT switches inserted too late @ 2013-07-24 11:55 amylaar at gcc dot gnu.org 2013-07-24 12:08 ` [Bug rtl-optimization/57968] MODE_EXIT switches inserted too early amylaar at gcc dot gnu.org ` (2 more replies) 0 siblings, 3 replies; 4+ messages in thread From: amylaar at gcc dot gnu.org @ 2013-07-24 11:55 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57968 Bug ID: 57968 Summary: MODE_EXIT switches inserted too late Product: gcc Version: 4.9.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: rtl-optimization Assignee: unassigned at gcc dot gnu.org Reporter: amylaar at gcc dot gnu.org I see a miscompilation of ___muldi3 for epiphany-elf; the witch to MODE_EXIT is done at the start of the exit block, even though it contains instructions that require a different mode. The return register on the epiphany is not likely spilled, and a large register file gives lots of freedom to do optimizations; when optimizig ___muldi3, at end end the return value is not so much copied as calculated piecemeal. There is some existing code in compute_pre_exit that is supposed to preserve computations that need a non-exit mode, but the way it is placed means it is only active when the immediate result is part of the return register. ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug rtl-optimization/57968] MODE_EXIT switches inserted too early 2013-07-24 11:55 [Bug rtl-optimization/57968] New: MODE_EXIT switches inserted too late amylaar at gcc dot gnu.org @ 2013-07-24 12:08 ` amylaar at gcc dot gnu.org 2013-07-30 10:25 ` chrbr at gcc dot gnu.org 2024-03-09 23:46 ` pinskia at gcc dot gnu.org 2 siblings, 0 replies; 4+ messages in thread From: amylaar at gcc dot gnu.org @ 2013-07-24 12:08 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57968 --- Comment #1 from Jorn Wolfgang Rennecke <amylaar at gcc dot gnu.org> --- A patch is here: http://gcc.gnu.org/ml/gcc-patches/2013-07/msg01081.html ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug rtl-optimization/57968] MODE_EXIT switches inserted too early 2013-07-24 11:55 [Bug rtl-optimization/57968] New: MODE_EXIT switches inserted too late amylaar at gcc dot gnu.org 2013-07-24 12:08 ` [Bug rtl-optimization/57968] MODE_EXIT switches inserted too early amylaar at gcc dot gnu.org @ 2013-07-30 10:25 ` chrbr at gcc dot gnu.org 2024-03-09 23:46 ` pinskia at gcc dot gnu.org 2 siblings, 0 replies; 4+ messages in thread From: chrbr at gcc dot gnu.org @ 2013-07-30 10:25 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57968 chrbr at gcc dot gnu.org changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |chrbr at gcc dot gnu.org --- Comment #2 from chrbr at gcc dot gnu.org --- Created attachment 30571 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30571&action=edit Same issue on SH4 Same problem with the attached test on 4.8.1 SH4 whereas I also see the EXIT block inserted before the FP use. Testing with your patch on 4.8 ^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug rtl-optimization/57968] MODE_EXIT switches inserted too early 2013-07-24 11:55 [Bug rtl-optimization/57968] New: MODE_EXIT switches inserted too late amylaar at gcc dot gnu.org 2013-07-24 12:08 ` [Bug rtl-optimization/57968] MODE_EXIT switches inserted too early amylaar at gcc dot gnu.org 2013-07-30 10:25 ` chrbr at gcc dot gnu.org @ 2024-03-09 23:46 ` pinskia at gcc dot gnu.org 2 siblings, 0 replies; 4+ messages in thread From: pinskia at gcc dot gnu.org @ 2024-03-09 23:46 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57968 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Target Milestone|--- |4.9.0 Resolution|--- |FIXED --- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Fixed a long time ago: r0-124444-gce4a94223ea08c (for GCC 4.9.0). ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2024-03-09 23:46 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2013-07-24 11:55 [Bug rtl-optimization/57968] New: MODE_EXIT switches inserted too late amylaar at gcc dot gnu.org 2013-07-24 12:08 ` [Bug rtl-optimization/57968] MODE_EXIT switches inserted too early amylaar at gcc dot gnu.org 2013-07-30 10:25 ` chrbr at gcc dot gnu.org 2024-03-09 23:46 ` pinskia at gcc dot gnu.org
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