[FFmpeg-devel] [PATCH] Assign unique values to AV_CPU_FLAG_IWMMXT and AV_CPU_FLAG_ALTIVEC.

[Ronald S. Bultje]

Hi,

On Wed, Sep 8, 2010 at 11:32 AM, Janne Grunau <janne-ffmpeg at jannau.net> wrote:
> On Wed, Sep 08, 2010 at 09:55:04AM -0400, Ronald S. Bultje wrote:
>> On Wed, Sep 8, 2010 at 7:44 AM, Janne Grunau <janne-ffmpeg at jannau.net> wrote:
>> > if (mm_flags && FF_MM_MMX)
>> > ? ? ? ?cpuflags |= SWS_CPU_CAPS_MMX;
>> > if (mm_flags && FF_MM_ALTIVEC)
>> > ? ? ? ?cpuflags |= SWS_CPU_CAPS_ALTIVEC;
>> >
>> > had strange results since SWS_CPU_CAPS_MMX != SWS_CPU_CAPS_ALTIVEC.
>> > Easily solveable with adding HAVE_(MMX|ALTIVEC) && to the ifs.
>>
>> This should all be under ARCH_PPC or HAVE_MMX and similar. x86-family
>> CPUs supporting altivec don't exist.
>
> yes, the working code has 'if (HAVE_ALTIVEC && mm_flags & FF_MM_ALTIVEC)'

Excellent. Stefano, do you think it makes sense to document these
flags a little so that it's obvious that altivec can only be used
conditionally based on HAVE_ALTIVEC, x86-flags based on HAVE_MMX etc.?
This should really be documented to prevent this from coming up again
or causing issues for people.

Thanks,
Ronald