[MPlayer-dev-eng] [PATCH] SSE detection fix for NetBSD/amd64
Reimar.Doeffinger at stud.uni-karlsruhe.de
Sun Jan 9 19:50:01 CET 2005
On Sun, Jan 09, 2005 at 07:10:55PM +0100, Guillaume POIRIER wrote:
> Le vendredi 07 janvier 2005 à 18:42 +0100, Aurelien Jacobs a écrit :
> > I didn't found any way to test OS SSE support on x86-64.
> > But AFAIK, there is no x86-64 OS which don't support SSE.
> > I guess it's safe to assume SEE support on x86-64, whatever the OS is.
> > So I propose the following patch, which should make everyone happy.
> > Anyone against it ?
> I'm not. This patch does work well, and allows some faster code to be
> I posted a bench last Thursday on XviD mailling list to compare the
> x86-64 version against IA-32.
> Here are the new figures:
> On x86-64
> XviD Pure C | XviD Edouard SIMD | lavc + SIMD
> Pass 1: 37fps | 78fps SSE: 90fps | 82fps SSE: 84fps
> Pass 2: 11fps | 32fps SSE: 36fps | 30fps SSE: 30fps
> Well, I'm quite puzzled why lavc doesn't get boosted by the activation
> of SSE, but regarding XviD, when It's run with a SSE1|2-aware mencoder,
> it gets a bonus 12%... not bad. Not bad at all!
That is because lavc uses cpudetection based in the code in
No idea why there a different implementations of this, and why the OS is
asked and doesn't just use the CPUID instruction (or is it e.g. possible for
the kernel to disable SSE? or CPUID?)...
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