[MPlayer-dev-eng] [PATCH] Runtime optimization march for x86_64

[Attila Kinali]

On Mon, 16 Oct 2006 22:17:03 -0600 (MDT)
Loren Merritt <lorenm at u.washington.edu> wrote:

> > BTW: Do we really need to check CPU's capability at run time for
> > x86-64? It architecturally supports MMX, SSE and SSE2 anyway and the
> > only advantage for a run time check is the possibility to make use of
> > 3DNow!.
> 
> Some SSE2 code is faster than MMX on Intel cpus, but slower on AMD. I 
> don't know if there's any of that in MPlayer/lavc yet, but if it's ever 
> added we'll want run-time detection even if we know SSE2 is supported.

Shouldnt than this detection be done on compile time?
And even if the asm code is slower, don't we lose quite some
performance with the function pointers?

			Attila Kinali
-- 
egp ist vergleichbar mit einem ikea bausatz fuer flugzeugtraeger
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