[FFmpeg-devel] [RFC] cpu specific implementation of libavutil functions

Luca Barbato lu_zero
Sun Sep 9 23:23:09 CEST 2007

Michael Niedermayer wrote:
> Hi
> On Wed, Sep 05, 2007 at 05:10:50PM +0200, Luca Barbato wrote:
>> Recently I got an altivec adler32 implementation from Sigbj?rn Skj?ret
>> and the main issue is how to plant it into libavutils and find a sane
>> general way.
> how much faster is that adler32 code?
> adler32 really should be limited by memory speed not by cpu


> 2. do we even have a working altivec detection routine? that what we do
> in dsputil is not what i would call working and i will not accept such
> hacks in libavutil

Currently altivec is checked by system dependent reporting or basic
sigill catching on altivec instruction. I could have an even more crazy
version like using fork() to execute the altivec code. Still this is to
my knowledge the only portable way to check.



Luca Barbato

Gentoo/linux Gentoo/PPC

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