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Re: EGCS performance ?
- To: N8TM at aol dot com
- Subject: Re: EGCS performance ?
- From: Joe Buck <jbuck at synopsys dot com>
- Date: Sat, 31 Oct 98 9:46:15 PST
- Cc: ruoccos at comm2000 dot it, egcs at cygnus dot com
> I've taken the liberty of modifying some of the LFK kernels so they don't
> depend on compilers recognizing specific oddly coded loops or optimizing
> obsolete syntax.
Many of those oddly coded loops are tuning for older Cray machines,
which do best if you can feed them lots of 64-element vector operations.
> This helps the commercial compilers as much as it does egcs,
> but makes the results more meaningful as a test of performance on reasonable
> source code.
However, many scientific programmers will be using Cray-tuned "dusty deck"
Fortran for a long time to come, based on the "if it isn't broke, don't
fix it" principle. I know that the Stanford SUIF people put a lot of
effort into high-level loop transformations to completely rearrange these
kinds of nested loops.