[Ffmpeg-cvslog] r6573 - trunk/libavcodec/cabac.h

[Michael Niedermayer]

Hi

On Sat, Oct 07, 2006 at 04:42:03PM +0300, Uoti Urpala wrote:
> On Sat, 2006-10-07 at 13:15 +0200, michael wrote:
> > Log:
> > several x86 renorm_cabac_decoder_once optimizations
> > START/STOP_TIMER benchmarking code for them
> > please benchmark on P4 & athlon
> > (ill remove the benchmarking code and the always slower variants as soon as p4/athlon benchmarks have been posted or commited)
> 
> Having START/STOP_TIMER there makes h264 about 50% slower so having them
> enabled by default even just until benchmarks are done doesn't seem like
> a good idea.

well then comment them out and svn ci


> 
> I did some benchmark runs of overall performance with the
> START/STOP_TIMER macros disabled, the optimization (the
> enabled-by-default asm version) made things about 1% slower than the C
> version. I think the asm was slower with reasonable confidence; I got
> several runs with C that were faster than the fastest run of the asm
> version.

could you test every of the alternative asms? iam not surprised that
this one is slower on amd

btw for testing you can use:
rm libavcodec/h264.o ; make ffmpeg_g && ./ffmpeg_g -v 9 -i foobar -y -f rawvideo /dev/null

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

In the past you could go to a library and read, borrow or copy any book
Today you'd get arrested for mere telling someone where the library is