------- Additional Comments From stevenb at suse dot de 2005-01-31 20:14
-------
Subject: Re: [meta-bug] optimizations that CSE still catches
My numbers for not disabling CSE completely but disabling path following
are a lot less pessimistic. This was on an AMD Opteron at 1600MHz:
GCC was configured as: configure --enable-threads=posix
--enable-languages="c,c++,f95"
GCC bootstrap times for 'make -j1 bootstrap && make install':
Bootstrap time base compiler: 2208 s
Bootstrap time peak compiler: 2150 s (-2.6%)
SPECint 64 bits
Total time for base compilation: 192 s
Total time for peak compilation: 180 s (-6.7%)
base peak peak/base
164.gzip 794 799 +0.63%
175.vpr 729 715 -1.92%
176.gcc 958 963 +0.52%
181.mcf 410 411 +0.24%
186.crafty 1362 1380 +1.32%
197.parser 558 558 =
252.eon X X
253.perlbmk 962 964 +0.21%
254.gap 774 776 +0.26%
255.vortex 1159 1162 +0.26%
256.bzip2 779 772 -0.90%
300.twolf 836 876 +4.78%
SPECfp 64 bits
Total time for base compilation: 212 s
Total time for peak compilation: 208 s (-1.9%)
base peak peak/base
168.wupwise 781 793 +1.53%
171.swim 690 687 -0.43%
172.mgrid 513 514 +0.02%
173.applu 624 624 =
177.mesa 1000 998 -0.20%
178.galgel X X
179.art 941 953 +1.28%
183.equake 817 820 +0.37%
187.facerec 674 677 +0.44%
188.ammp 859 859 =
189.lucas 858 858 =
191.fma3d 699 698 -0.14%
200.sixtrack 382 382 =
301.apsi 770 771 +0.12%
SPECint 32 bits
Total time for base compilation: 257 s
Total time for peak compilation: 246 s (-4.5%)
base peak peak/base
164.gzip 696 700 +0.57%
175.vpr 691 710 +2.74%
176.gcc 884 875 -1.02%
181.mcf 528 530 +0.38%
186.crafty 920 922 +0.22%
197.parser 629 634 +0.79%
252.eon 970 963 -0.72%
253.perlbmk 935 938 +0.32%
254.gap X X
255.vortex X X
256.bzip2 678 681 +0.04%
300.twolf 974 966 -0.82%
SPECfp 32 bits
Total time for base compilation: 210 s
Total time for peak compilation: 204 s (-2.9%)
base peak peak/base
168.wupwise 672 658 -2.08%
171.swim 692 696 +0.58%
172.mgrid 370 370 =
173.applu 580 580 =
177.mesa 678 655 -3.39%
178.galgel X X
179.art 484 483 -0.21%
183.equake 822 821 -0.12%
187.facerec 616 617 +0.16%
188.ammp 712 713 +0.14%
189.lucas 693 695 +0.20%
191.fma3d 716 716 =
200.sixtrack 422 422 =
301.apsi 685 685 =
The SPEC numbers are the mean of three runs, so that's pretty solid.
Index: params.def
===================================================================
RCS file: /cvs/gcc/gcc/gcc/params.def,v
retrieving revision 1.53
diff -u -3 -p -r1.53 params.def
--- params.def 20 Jan 2005 12:45:12 -0000 1.53
+++ params.def 31 Jan 2005 17:09:21 -0000
@@ -321,7 +321,7 @@ DEFPARAM(PARAM_MIN_CROSSJUMP_INSNS,
DEFPARAM(PARAM_MAX_CSE_PATH_LENGTH,
"max-cse-path-length",
"The maximum length of path considered in cse",
- 10, 0, 0)
+ 1, 0, 0)
/* The cost of expression in loop invariant motion that is considered
expensive. */
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19721
