[FFmpeg-devel] [PATCH] Dsputilize some functions from APE decode 1/2 - Altivec implementation
Thu Jul 10 19:09:17 CEST 2008
On Thu, Jul 10, 2008 at 08:43:12AM -0600, Loren Merritt wrote:
> On Thu, 10 Jul 2008, Kostya wrote:
> > On Tue, Jul 08, 2008 at 03:18:12PM -0600, Loren Merritt wrote:
> >> Entirely untested (I don't have a ppc), but this looks like it should be
> >> faster. Your other functions would benefit from similar.
> >> For that matter, a whole lot of dsp functions put lvsl inside the loop
> >> when it should be constant (assuming stride%16==0).
> >> --Loren Merritt
> > It does not work as supposed modifying only the start of output array.
> > Thanks for trying anyway.
> That's what I get for trying to write without a compiler.
> should be
> + pv1 += 2;
> + pv2 += 2;
> --Loren Merritt
Now it works fine but on my G4 under macosx it gives such numbers:
clocks for 10 million cycles on arrays of length 256
unoptimized gcc 3.3
unoptimized gcc 4.0.1
I guess it was MMX that was designed with black magic in mind.
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