Hi, On Wed, Jan 14, 2015 at 4:23 PM, James Almer <jamr...@gmail.com> wrote:
> On 14/01/15 1:59 PM, Michael Niedermayer wrote: > > On Wed, Jan 14, 2015 at 01:53:48AM -0300, James Almer wrote: > >> unpack_2ch is already using sse float ops only, and pack_2ch is a > trivial change. > >> Rename both to float_to_float for consistency. > >> > >> Signed-off-by: James Almer <jamr...@gmail.com> > >> --- > >> libswresample/x86/audio_convert.asm | 14 ++++++++------ > >> libswresample/x86/audio_convert_init.c | 11 +++++++---- > >> 2 files changed, 15 insertions(+), 10 deletions(-) > >> > >> diff --git a/libswresample/x86/audio_convert.asm > b/libswresample/x86/audio_convert.asm > >> index 1617e0b..c13c26f 100644 > >> --- a/libswresample/x86/audio_convert.asm > >> +++ b/libswresample/x86/audio_convert.asm > >> @@ -60,8 +60,8 @@ pack_2ch_%2_to_%1_u_int %+ SUFFIX > >> punpcklwd m0, m2 > >> punpckhwd m1, m2 > >> %else > >> - punpckldq m0, m2 > >> - punpckhdq m1, m2 > >> + unpcklps m0, m2 > >> + unpckhps m1, m2 > >> %endif > >> %6 m0,m1,m2,m3,m4,m5 > >> %else > > > > did you benchmark this ? > > ive just checked and on Pentium M, Core Solo and Core Duo these are > > listed as having only 1/5 the throughput > > on sandybridge they are still listed with half the throughput than > > their integer counterparts > > i didnt benchmark it though > > No, i didn't benchmark. And you're right, even on recent CPUs they seem to > have half the throughput as the integer counterparts. > Do you think it will mean a considerable performance hit? These functions > aren't even that important in audio processing anyway (perf shows they > represent less than 1% of total cpu time when doing pcm -> pcm). > > Nonetheless, considering this maybe the other functions should be changed > to not use SBUTTERFLYPS. Well, you can have SSE and SSE2 versions, right? That way it works for people with super-old CPUs (if you care about them), but still gives the better performance for 99.9% of the (x86) world with SSE2 or higher CPUs. Ronald _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel