[FFmpeg-devel] [PATCH] swscale: fix build with --enable-runtime-cpudetect --disable-mmx/mmx2/amd3dnow

[Anssi Hannula]

On 02.02.2011 20:22, M?ns Rullg?rd wrote:
> Anssi Hannula <anssi.hannula at iki.fi> writes:
> 
>> Commit 0fc29f2708a "swscale: simplify selection of optimizations to
>> compile." (25 Aug 2010) changed the behaviour so that with
>> --enable-runtime-cpudetect --disable-mmx/mmx2/amd3dnow the instruction
>> sets are actually disabled.
>>
>> However, ff_getSwsFunc() still calls the respective initialization
>> functions which no longer exist, causing a build failure.
>>
>> Fix that by putting those calls under #if as well.
>> ---
>>  libswscale/swscale.c |   15 +++++++++++----
>>  1 files changed, 11 insertions(+), 4 deletions(-)
>>
>> diff --git a/libswscale/swscale.c b/libswscale/swscale.c
>> index 375171f..8d7bb73 100644
>> --- a/libswscale/swscale.c
>> +++ b/libswscale/swscale.c
>> @@ -1262,19 +1262,26 @@ SwsFunc ff_getSwsFunc(SwsContext *c)
>>
>>  #if ARCH_X86
>>      // ordered per speed fastest first
>> +#if COMPILE_MMX2
>>      if (flags & SWS_CPU_CAPS_MMX2) {
>>          sws_init_swScale_MMX2(c);
>>          return swScale_MMX2;
>> -    } else if (flags & SWS_CPU_CAPS_3DNOW) {
>> +    }
>> +#endif
>> +#if COMPILE_3DNOW
>> +    if (flags & SWS_CPU_CAPS_3DNOW) {
>>          sws_init_swScale_3DNow(c);
>>          return swScale_3DNow;
>> -    } else if (flags & SWS_CPU_CAPS_MMX) {
>> +    }
>> +#endif
>> +#if COMPILE_MMX
>> +    if (flags & SWS_CPU_CAPS_MMX) {
>>          sws_init_swScale_MMX(c);
>>          return swScale_MMX;
>> -    } else {
>> +    }
>> +#endif
> 
> I somehow suspect these should be HAVE_FOO instead, but this file is
> an ifdef jungle and I could be wrong.

The COMPILE_FOO are defined to HAVE_FOO when runtime cpudetection is in
use. However, as the actual compilation of those functions depends
directly on COMPILE_FOO (and only indirectly on HAVE_FOO), I had thought
it is better to make the calls depend on the same #define.

-- 
Anssi Hannula