Re: K8, EFFICEON and CORE2 support the cmovxx instructions.

From: Willy Tarreau
Date: Sat Mar 15 2008 - 17:13:00 EST


On Sat, Mar 15, 2008 at 10:06:32PM +0100, Alexander van Heukelum wrote:
> > > I'm quite sure that K8, EFFICEON and CORE2 support HAVE_CMOV, but
> > > they did not set X86_CMOV.
> > >
> >
> > Crusoe has CMOV as well.

So does GEODE_LX BTW

> I believe you... and the Makefile_32.cpu: it gets a -march=i686. I
> also found out that I missed X86_ELAN, which is treated as a i486.
>
> Also, MGEODE_LX does not get any optimization flags. I think that
> is unintentional, but what should they be?

in my experience (on user-space code), optimizing for "i586" gives
good results. However, the cache is small, so everything which can
reduce code size (especially loop/jump/function alignment) is worth
checking.

Regards,
Willy

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