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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)
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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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