This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: -freduce-all-givs and fortran
- To: Jan Hubicka <jh at suse dot cz>
- Subject: Re: -freduce-all-givs and fortran
- From: Andreas Jaeger <aj at suse dot de>
- Date: Thu, 06 Sep 2001 10:33:29 +0200
- Cc: gcc-patches at gcc dot gnu dot org, gcc at gcc dot gnu dot org
- References: <20010905155814.D10747@atrey.karlin.mff.cuni.cz>
Just for reference, I've run the SPECfp2000 Fortran77 tests once with
these flags on an AMD Athlon 1.133 Ghz system:
Base: -O2 -march=athlon -malign-double
Peak: -O2 -march=athlon -malign-double -fno-move-all-movables -fno-reduce-all-givs
Here're the results:
Estimated Estimated
Base Base Base Peak Peak Peak
Benchmarks Ref Time Run Time Ratio Ref Time Run Time Ratio
------------ -------- -------- -------- -------- -------- --------
168.wupwise 1600 418 382* 1600 417 384*
171.swim 3100 1213 256* 3100 1040 298*
172.mgrid 1800 1017 177* 1800 1117 161*
173.applu 2100 759 277* 2100 813 258*
200.sixtrack 1100 577 191* 1100 534 206*
301.apsi had some errors and couldn't be tested.
Using -fno-move-all-movables -fno-reduce-all-givs is a performance
gain for 171.swim and 200.sixtrack but pessimizes 172.grid and
173.app, 168.wupwise is indifferent.
Andreas
--
Andreas Jaeger
SuSE Labs aj@suse.de
private aj@arthur.inka.de
http://www.suse.de/~aj