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Mail Archives: pgcc/2000/02/18/15:38:52

Date: Fri, 18 Feb 2000 13:05:54 +0100
From: Marc Lehmann <marc AT gimp DOT org>
To: pgcc AT delorie DOT com
Cc: law AT sgi DOT com
Subject: Re: Big slowdown on -mpentium/-mpentiumpro, short_int add
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On Thu, Feb 17, 2000 at 08:24:32AM -0800, Linda Walsh <law AT sgi DOT com> wrote:
> Showed about a 30-40% slowdown when using the -mpentium or -mpentiumpro

on which cpu, and slowdown compared to what?

> Note the test suite is copyright, but I'm excerpting this section for
> educational (to demonatrate a problem) purposes.

Das that make it more legal ;) Anyway, thanks a lot for the snippet!

I do not know the reason for the slowdown (yet), but "short" is about
the slowest datatype for pentium-type systems, and it could very well be
that suboptimal scheduling even of a single insns can make such a large
difference.

-- 
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