On 10.03.2016, at 12:01, Ismail Donmez <ism...@i10z.com> wrote: > On Thu, Mar 10, 2016 at 12:04 PM, wm4 <nfx...@googlemail.com> wrote: >> On Thu, 10 Mar 2016 16:53:12 +0700 >> Muhammad Faiz <mfc...@gmail.com> wrote: >> >>> I use intrinsic because writing asm using nasm or inline asm >>> is difficult task for me. >>> >>> [PATCH 1/3] configure: add x86 intrinsic support >>> [PATCH 2/3] avfilter/avf_showcqt: cqt_calc x86 optimization >>> [PATCH 3/3] avfilter/avf_showcqt: draw_bar x86 optimization >>> >>> Thank's >> >> We generally don't accept intrinsic in ffmpeg. > > Given this policy has roots from gcc 2.x times, it might be a good > idea to discuss it again in the context of gcc5 and clang 3.8 and > later.
I think last time I tried it on some gcc 4.x the intrinsics generated code significantly slower than the non-SIMD code (asm was about 4x faster, and it was a trivial raw audio format conversion loop). So from my point of view I still think with intrinsics you have to expect a > 4x performance variation, which for me is "it might be better to just not optimize at all" level. Maybe in another 5 years... But honestly it seems to me autovectorization might get there before intrinsics... _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
