This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: 19980707 built on win95/i686-pc-cygwin32
- To: N8TM at aol dot com
- Subject: Re: 19980707 built on win95/i686-pc-cygwin32
- From: Jeffrey A Law <law at cygnus dot com>
- Date: Sat, 11 Jul 1998 23:46:35 -0600
- cc: amylaar at cygnus dot co dot uk, egcs at cygnus dot com
- Reply-To: law at cygnus dot com
In message <57600ee5.35a7006b@aol.com>you write:
> I wasn't aware of that option. It certainly accentuates the differences in
> performance between egcs/g77 and g77-0.5.23 on Linux/P II. Livermore Kernel
> (double precision) loops vary from 50% faster for egcs with this option to 50%
> faster for g77-0.5.23. On win95, however, the effects of -fno-gcse seem to be
> all favorable, bringing the performance of egcs on win95 almost up to where it
> is on Linux, and well above g77-0.5.23 on win95. win95 must be poisoning the
> cache, if I take your suggestion.
Any chance you could analyze this code in more detail? I'm quite
interested in cases where gcse makes code slower.
THough given the variation in your results, this may be yet another
"double alignment" issue.
jeff