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* [Bug target/34501] The vector cost model does not seem suited for Intel Core2Duo
[not found] <bug-34501-4@http.gcc.gnu.org/bugzilla/>
@ 2011-12-06 11:46 ` dominiq at lps dot ens.fr
0 siblings, 0 replies; 7+ messages in thread
From: dominiq at lps dot ens.fr @ 2011-12-06 11:46 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34501
Dominique d'Humieres <dominiq at lps dot ens.fr> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
Resolution| |FIXED
--- Comment #6 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2011-12-06 11:45:39 UTC ---
Although I don't know if the cost model is perfectly tuned for the Intel
Core2Duo, the particular instance of this PR has been fixed since a long time
(see pr34265 and pr50904), on trunk at r182043, I now get on a slightly faster
proc (2.5Ghz vs. 2.1Ghz):
[macbook] lin/test% time gfc -O3 -ffast-math -funroll-loops induct.f90
7.969u 0.101s 0:08.07 99.8% 0+0k 0+40io 0pf+0w
[macbook] lin/test% time a.out > /dev/null
13.062u 0.026s 0:13.09 99.9% 0+0k 0+0io 0pf+0w
[macbook] lin/test% time gfc -O3 -ffast-math -funroll-loops induct.f90 --param
min-vect-loop-bound=2
7.965u 0.110s 0:08.08 99.8% 0+0k 0+23io 0pf+0w
[macbook] lin/test% time a.out > /dev/null
13.063u 0.027s 0:13.09 99.9% 0+0k 0+0io 0pf+0w
So I am closing the PR as fixed. Thanks for all the work leading to a nice
speed-up.
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/34501] The vector cost model does not seem suited for Intel Core2Duo
2007-12-16 21:02 [Bug tree-optimization/34501] New: " dominiq at lps dot ens dot fr
` (4 preceding siblings ...)
2010-05-09 19:38 ` howarth at nitro dot med dot uc dot edu
@ 2010-05-09 23:12 ` howarth at nitro dot med dot uc dot edu
5 siblings, 0 replies; 7+ messages in thread
From: howarth at nitro dot med dot uc dot edu @ 2010-05-09 23:12 UTC (permalink / raw)
To: gcc-bugs
------- Comment #5 from howarth at nitro dot med dot uc dot edu 2010-05-09 23:12 -------
Okay, my mistake. It appears that the default builds for both
i386-apple-darwin* and x86_64-apple-darwin* are both leaving -mtune set at
generic. However it would be a nice aim for gcc 4.6.0 to have the processor
specific costs outperform the generic tuning when invoked.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34501
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/34501] The vector cost model does not seem suited for Intel Core2Duo
2007-12-16 21:02 [Bug tree-optimization/34501] New: " dominiq at lps dot ens dot fr
` (3 preceding siblings ...)
2010-05-09 19:27 ` dirtyepic at gentoo dot org
@ 2010-05-09 19:38 ` howarth at nitro dot med dot uc dot edu
2010-05-09 23:12 ` howarth at nitro dot med dot uc dot edu
5 siblings, 0 replies; 7+ messages in thread
From: howarth at nitro dot med dot uc dot edu @ 2010-05-09 19:38 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from howarth at nitro dot med dot uc dot edu 2010-05-09 19:38 -------
With gcc-4.5.0 built as...
Using built-in specs.
COLLECT_GCC=gcc-4
COLLECT_LTO_WRAPPER=/sw/lib/gcc4.5/libexec/gcc/x86_64-apple-darwin10.3.0/4.5.0/lto-wrapper
Target: x86_64-apple-darwin10.3.0
Configured with: ../gcc-4.5.0/configure --prefix=/sw --prefix=/sw/lib/gcc4.5
--mandir=/sw/share/man --infodir=/sw/lib/gcc4.5/info
--enable-languages=c,c++,fortran,objc,obj-c++,java --with-gmp=/sw
--with-libiconv-prefix=/sw --with-ppl=/sw --with-cloog=/sw --with-mpc=/sw
--with-system-zlib --x-includes=/usr/X11R6/include --x-libraries=/usr/X11R6/lib
--program-suffix=-fsf-4.5
Thread model: posix
gcc version 4.5.0 (GCC)
I get the following from...
$ touch t.cc
$ gcc -fverbose-asm t.cc -S
more t.s
# GNU C++ (GCC) version 4.5.0 (x86_64-apple-darwin10.3.0)
# compiled by GNU C version 4.5.0, GMP version 4.3.1, MPFR version
2.4.2-p3, MPC version 0.8
# GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
# options passed: -D__DYNAMIC__ t.cc -fPIC -mmacosx-version-min=10.6.3
# -mtune=generic -fverbose-asm
# options enabled: -fPIC -falign-loops -fargument-alias
# -fasynchronous-unwind-tables -fauto-inc-dec -fbranch-count-reg -fcommon
# -fdelete-null-pointer-checks -fearly-inlining
# -feliminate-unused-debug-types -fexceptions -ffunction-cse -fgcse-lm
# -fident -finline-functions-called-once -fira-share-save-slots
# -fira-share-spill-slots -fivopts -fkeep-static-consts
# -fleading-underscore -fmerge-debug-strings -fmove-loop-invariants
# -fpeephole -freg-struct-return -fsched-critical-path-heuristic
# -fsched-dep-count-heuristic -fsched-group-heuristic -fsched-interblock
# -fsched-last-insn-heuristic -fsched-rank-heuristic -fsched-spec
# -fsched-spec-insn-heuristic -fsched-stalled-insns-dep -fshow-column
# -fsigned-zeros -fsplit-ivs-in-unroller -ftrapping-math -ftree-cselim
# -ftree-forwprop -ftree-loop-im -ftree-loop-ivcanon -ftree-loop-optimize
# -ftree-parallelize-loops= -ftree-phiprop -ftree-pta -ftree-reassoc
# -ftree-scev-cprop -ftree-slp-vectorize -ftree-vect-loop-version
# -funit-at-a-time -funwind-tables -fvect-cost-model -fverbose-asm
# -fzero-initialized-in-bss -gstrict-dwarf -m128bit-long-double -m64
# -m80387 -maccumulate-outgoing-args -malign-stringops -mfancy-math-387
# -mfp-ret-in-387 -mfused-madd -mieee-fp -mmmx -mno-sse4 -mpush-args
# -mred-zone -msse -msse2 -msse3
which shows that -mtune was set to generic for that release. I'll double check
with current gcc trunk but now suspect it has been changed to core2.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34501
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/34501] The vector cost model does not seem suited for Intel Core2Duo
2007-12-16 21:02 [Bug tree-optimization/34501] New: " dominiq at lps dot ens dot fr
` (2 preceding siblings ...)
2010-05-09 16:10 ` howarth at nitro dot med dot uc dot edu
@ 2010-05-09 19:27 ` dirtyepic at gentoo dot org
2010-05-09 19:38 ` howarth at nitro dot med dot uc dot edu
2010-05-09 23:12 ` howarth at nitro dot med dot uc dot edu
5 siblings, 0 replies; 7+ messages in thread
From: dirtyepic at gentoo dot org @ 2010-05-09 19:27 UTC (permalink / raw)
To: gcc-bugs
------- Comment #3 from dirtyepic at gentoo dot org 2010-05-09 19:26 -------
Nothing changed. -march=native sets -mtune=core2 on my Penyrn as far back as
4.3, and you can see in PR44046 that Nehalem did the same before the patch.
--
dirtyepic at gentoo dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |dirtyepic at gentoo dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34501
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/34501] The vector cost model does not seem suited for Intel Core2Duo
2007-12-16 21:02 [Bug tree-optimization/34501] New: " dominiq at lps dot ens dot fr
2007-12-16 21:20 ` [Bug target/34501] " pinskia at gcc dot gnu dot org
2009-09-17 9:52 ` ubizjak at gmail dot com
@ 2010-05-09 16:10 ` howarth at nitro dot med dot uc dot edu
2010-05-09 19:27 ` dirtyepic at gentoo dot org
` (2 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: howarth at nitro dot med dot uc dot edu @ 2010-05-09 16:10 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from howarth at nitro dot med dot uc dot edu 2010-05-09 16:10 -------
It appears that r159202 (for gcc trunk) and r159203 (for gcc-4_5-branch) has
escalated this problem by defaulting some chipsets to the core2 tuning. PR34501
should be bumped to a P1 for both gcc trunk and gcc-4_5-branch to make sure it
gets fixed before the next releases. Otherwise users of Nehalem, Westmere,
Penryn and Merom class processors will find their default code generation
pessimized.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34501
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/34501] The vector cost model does not seem suited for Intel Core2Duo
2007-12-16 21:02 [Bug tree-optimization/34501] New: " dominiq at lps dot ens dot fr
2007-12-16 21:20 ` [Bug target/34501] " pinskia at gcc dot gnu dot org
@ 2009-09-17 9:52 ` ubizjak at gmail dot com
2010-05-09 16:10 ` howarth at nitro dot med dot uc dot edu
` (3 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: ubizjak at gmail dot com @ 2009-09-17 9:52 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from ubizjak at gmail dot com 2009-09-17 09:52 -------
Adding H.J. to CC.
--
ubizjak at gmail dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |hjl dot tools at gmail dot
| |com
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2009-09-17 09:52:01
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34501
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Bug target/34501] The vector cost model does not seem suited for Intel Core2Duo
2007-12-16 21:02 [Bug tree-optimization/34501] New: " dominiq at lps dot ens dot fr
@ 2007-12-16 21:20 ` pinskia at gcc dot gnu dot org
2009-09-17 9:52 ` ubizjak at gmail dot com
` (4 subsequent siblings)
5 siblings, 0 replies; 7+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2007-12-16 21:20 UTC (permalink / raw)
To: gcc-bugs
--
pinskia at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |pinskia at gcc dot gnu dot
| |org
Severity|normal |enhancement
Component|tree-optimization |target
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34501
^ permalink raw reply [flat|nested] 7+ messages in thread
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[not found] <bug-34501-4@http.gcc.gnu.org/bugzilla/>
2011-12-06 11:46 ` [Bug target/34501] The vector cost model does not seem suited for Intel Core2Duo dominiq at lps dot ens.fr
2007-12-16 21:02 [Bug tree-optimization/34501] New: " dominiq at lps dot ens dot fr
2007-12-16 21:20 ` [Bug target/34501] " pinskia at gcc dot gnu dot org
2009-09-17 9:52 ` ubizjak at gmail dot com
2010-05-09 16:10 ` howarth at nitro dot med dot uc dot edu
2010-05-09 19:27 ` dirtyepic at gentoo dot org
2010-05-09 19:38 ` howarth at nitro dot med dot uc dot edu
2010-05-09 23:12 ` howarth at nitro dot med dot uc dot edu
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