ff_cpu_cpuid routine (in libavutil/x86/cpuid.asm) clears ECX
register before cpuid instruction. Inline asm version
(in libavutil/x86/cpu.c) doesn't do this.
As a result, FFmpeg will probably misdetect AVX2/BMI1/BMI2
if yasm is not enabled.
As far as I understand GNU asm, the last line of cpuid macro
should be changed from
: "0" (index))
to
: "0" (index), "2"(0))
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
