[FFmpeg-devel] [PATCH] MMX/SSE2 qpel functions for RV40

Mathieu Velten matmaul
Tue Jan 6 14:48:46 CET 2009


2009/1/6 David Conrad <lessen42 at gmail.com>:
> On Jan 5, 2009, at 1:35 PM, Mathieu Velten wrote:
>
>> 2009/1/5 Michael Niedermayer <michaelni at gmx.at>:
>>> you can access constants like ff_pw_5 through MANGLE() thus bypassing
>>> gccs register deallocator
>>
>> thanks, new patch attached based on the first version with
>> MANGLE(ff_pw_5).
>
> Unfortunately, this doesn't actually help because ff_pw_5 was accessed
> through the PIC register originally, which gcc still reserves despite
> not needing to be used in the asm block. IMO if this is faster or if
> you consider it cleaner than the 6 register version (which does work)
> then use #ifdef HAVE_7REGS. I don't particularly care if it's usable
> with pic, just that ffmpeg compiles.

I'll let michael decide what he prefers. I can use MANGLE() in the 6
registers version too if he prefers this one.


Mathieu Velten




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