[Ffmpeg-devel] RUNTIME_CPUDETECT broken on PPC due to -maltivec

[Sam Hocevar]

On Fri, Mar 09, 2007, matthieu castet wrote:

> >   Contrary to common belief, when using -maltivec gcc *can* generate
> >AltiVec code in unexpected, non-vector-using places. Whether this is the
> >correct behaviour or not, I don't know, but it's gcc's behaviour. And
> >without -maltivec, there is no way to include <altivec.h> and use vector
> >types.
>
> Doesn't the same apply for x86 or other arches ?

   In theory, yes; in practice, ffmpeg only uses -mfoo for AltiVec.
Other extended instructions such as MMX are implemented using asm()
calls rather than the intrinsics.

Regards,
-- 
Sam.