[FFmpeg-devel] [PATCH 1/2] lavu/intmath.h: Add msvc/icl ctzll optimisations.

James Almer jamrial at gmail.com
Fri Oct 16 00:46:40 CEST 2015

On 10/15/2015 7:25 PM, Matt Oliver wrote:
> ICC defines __GNUC__ but ICL does not! ICC (being the linux variant)
> supports all the same functions as gcc so theres no need in this case for
> special handling. However ICL defines _MSC_VER so this is correct.

Ah, good to know then.

>> >
>>> > > +#define ff_ctzll ff_ctzll_c
>>> > > +static av_always_inline av_const int ff_ctzll_c(long long v)
>> >
>> > nit: ff_ctzll_x86 for the inline version. And you need to check
>> > HAVE_INLINE_ASM for it as
>> > well.
>> >
> I didnt put the HAVE_INLINE_ASM check as at this point we know its ICL and
> as ICL always has inline support so I assumed it was redundant. Given that
> is there actually a need to check it?

You can disable it during configure with --disable-inline-asm.
But since it's apparently mainly meant for lavc/lavfi simd (judging by other
lavu arch headers like intreadwrite.h that don't bother checking it) you can
leave it as is.

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