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* [Bug middle-end/33966] New: Revision 129625 caused 1% slowdown on 200.sixtrack
@ 2007-11-01 4:26 hjl at lucon dot org
2007-11-01 10:23 ` [Bug middle-end/33966] Revision 129625 caused 11% " ubizjak at gmail dot com
` (2 more replies)
0 siblings, 3 replies; 5+ messages in thread
From: hjl at lucon dot org @ 2007-11-01 4:26 UTC (permalink / raw)
To: gcc-bugs
Revision 129625
http://gcc.gnu.org/ml/gcc-cvs/2007-10/msg00730.html
caused 11% drop in performance for 200.sixtrack in SPEC CPU 2000
with -O2 -ffast-math on Core 2 Duo 64bit. That patch caused very
different codes generated for 200.sixtrack on x86-64.
--
Summary: Revision 129625 caused 1% slowdown on 200.sixtrack
Product: gcc
Version: 4.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: hjl at lucon dot org
GCC target triplet: x86_64-unknown-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33966
^ permalink raw reply [flat|nested] 5+ messages in thread* [Bug middle-end/33966] Revision 129625 caused 11% slowdown on 200.sixtrack 2007-11-01 4:26 [Bug middle-end/33966] New: Revision 129625 caused 1% slowdown on 200.sixtrack hjl at lucon dot org @ 2007-11-01 10:23 ` ubizjak at gmail dot com 2007-11-01 11:36 ` rguenth at gcc dot gnu dot org 2007-11-01 11:40 ` rguenth at gcc dot gnu dot org 2 siblings, 0 replies; 5+ messages in thread From: ubizjak at gmail dot com @ 2007-11-01 10:23 UTC (permalink / raw) To: gcc-bugs ------- Comment #1 from ubizjak at gmail dot com 2007-11-01 10:23 ------- PR Header should say 11%, not 1%. -- ubizjak at gmail dot com changed: What |Removed |Added ---------------------------------------------------------------------------- Summary|Revision 129625 caused 1% |Revision 129625 caused 11% |slowdown on 200.sixtrack |slowdown on 200.sixtrack http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33966 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/33966] Revision 129625 caused 11% slowdown on 200.sixtrack 2007-11-01 4:26 [Bug middle-end/33966] New: Revision 129625 caused 1% slowdown on 200.sixtrack hjl at lucon dot org 2007-11-01 10:23 ` [Bug middle-end/33966] Revision 129625 caused 11% " ubizjak at gmail dot com @ 2007-11-01 11:36 ` rguenth at gcc dot gnu dot org 2007-11-01 11:40 ` rguenth at gcc dot gnu dot org 2 siblings, 0 replies; 5+ messages in thread From: rguenth at gcc dot gnu dot org @ 2007-11-01 11:36 UTC (permalink / raw) To: gcc-bugs ------- Comment #2 from rguenth at gcc dot gnu dot org 2007-11-01 11:36 ------- Note I didn't experience any sixtrack regression (-O3 and -O3 -funroll-loops -ffast-math) on Opteron. This is very likely a partitioning issue, as the --param max-aliased-vops is different for -O2 vs. -O3 and sixtrack likely "lived on the edge" with the -O2 setting. The patch mainly changed which variables with the same partitioning score are considered for partitioning. So if at all, this is a partitioning/scoring bug. -- rguenth at gcc dot gnu dot org changed: What |Removed |Added ---------------------------------------------------------------------------- CC|rguenther at suse dot de |rguenth at gcc dot gnu dot | |org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33966 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/33966] Revision 129625 caused 11% slowdown on 200.sixtrack 2007-11-01 4:26 [Bug middle-end/33966] New: Revision 129625 caused 1% slowdown on 200.sixtrack hjl at lucon dot org 2007-11-01 10:23 ` [Bug middle-end/33966] Revision 129625 caused 11% " ubizjak at gmail dot com 2007-11-01 11:36 ` rguenth at gcc dot gnu dot org @ 2007-11-01 11:40 ` rguenth at gcc dot gnu dot org 2 siblings, 0 replies; 5+ messages in thread From: rguenth at gcc dot gnu dot org @ 2007-11-01 11:40 UTC (permalink / raw) To: gcc-bugs ------- Comment #3 from rguenth at gcc dot gnu dot org 2007-11-01 11:40 ------- Current partitioning has several problems: 1) Accounting only accounts for memory references through pointers. 2) Accounting for the number of VOPs a statement will generate and accounting for how many accesses a memory symbol will experience are mixed (thus not allowing to weight these factors differently easily) 3) The goal the pscore function tries to set at is not clear (partly due to reason 2). I have some ideas/patches on this side, but it's late in stage3 and we'll get (performance) disruption by the PR33870 fix on the partitioning side as well. -- rguenth at gcc dot gnu dot org changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |dnovillo at gcc dot gnu dot | |org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33966 ^ permalink raw reply [flat|nested] 5+ messages in thread
[parent not found: <bug-33966-4@http.gcc.gnu.org/bugzilla/>]
* [Bug middle-end/33966] Revision 129625 caused 11% slowdown on 200.sixtrack [not found] <bug-33966-4@http.gcc.gnu.org/bugzilla/> @ 2012-01-28 3:45 ` pinskia at gcc dot gnu.org 0 siblings, 0 replies; 5+ messages in thread From: pinskia at gcc dot gnu.org @ 2012-01-28 3:45 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33966 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution| |FIXED Target Milestone|--- |4.6.0 --- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> 2012-01-28 03:15:52 UTC --- This is all fixed in 4.6.0, we only have one partition now and use an alias oracle for that one partition. So closing as fixed. ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2012-01-28 3:16 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
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2007-11-01 4:26 [Bug middle-end/33966] New: Revision 129625 caused 1% slowdown on 200.sixtrack hjl at lucon dot org
2007-11-01 10:23 ` [Bug middle-end/33966] Revision 129625 caused 11% " ubizjak at gmail dot com
2007-11-01 11:36 ` rguenth at gcc dot gnu dot org
2007-11-01 11:40 ` rguenth at gcc dot gnu dot org
[not found] <bug-33966-4@http.gcc.gnu.org/bugzilla/>
2012-01-28 3:45 ` pinskia at gcc dot gnu.org
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