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SubjectRe: [patch] longstanding chksum patch
mingo@chiara.csoma.elte.hu wrote:
>
> On Thu, 9 Sep 1999, Andrea Arcangeli wrote:
>
> > - testl %esi, %esi
> > + clc
>
> you've just slowed the code down. clc does not pair. testl %esi, %esi
> does.

minor correction - actually, as this is 686 code, it does. (i remember
playing with this too, and mingo _is_ right - it comes out slower anyway
(depending on aligment etc). Actually it's even more interesting --
you can time the difference when using different registers as testl
arguments (the testl only has to clear CF so you can just pick one))


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