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Re: contribution
- From: Toon Moene <toon at moene dot indiv dot nluug dot nl>
- To: Alexey Starovoytov <stork at sun dot com>
- Cc: Andi Kleen <ak at suse dot de>, gcc at gcc dot gnu dot org
- Date: Fri, 12 Apr 2002 22:49:29 +0200
- Subject: Re: contribution
- Organization: Moene Computational Physics, Maartensdijk, The Netherlands
- References: <Pine.GSO.4.31.0204121042030.15886-100000@boojum>
Alexey Starovoytov wrote:
> On 12 Apr 2002, Andi Kleen wrote:
> > You could compiled 172.mgrid with gcc twice this way and it showed 48%
> > improvement ? Or did you use a different compiler as backend?
> It was gcc3.0.4 as a backend.
mgrid is one of those codes that heavily pays for reruning loop
optimisation (as it is now).
At least looking at the generated assembler, g77 -O2 -fno-rerun-loop-opt
produces much better code.
--
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