On Thu, Jan 14, 2016 at 6:42 PM, James Almer <jamr...@gmail.com> wrote: > On 1/14/2016 7:46 PM, Ganesh Ajjanagadde wrote: >> This improves accuracy (very slightly) and speed for processors having >> fma3. >> >> Sample benchmark (fate flac-16-lpc-cholesky, Haswell): >> old: >> 5993610 decicycles in ff_lpc_calc_coefs, 64 runs, 0 skips >> 5951528 decicycles in ff_lpc_calc_coefs, 128 runs, 0 skips >> >> new: >> 5252410 decicycles in ff_lpc_calc_coefs, 64 runs, 0 skips >> 5232869 decicycles in ff_lpc_calc_coefs, 128 runs, 0 skips >> >> Tested with FATE and --disable-fma3, also examined contents of >> lavu/lls-test. >> >> Reviewed-by: James Almer <jamr...@gmail.com> >> Reviewed-by: Henrik Gramner <hen...@gramner.com> >> Signed-off-by: Ganesh Ajjanagadde <gajjanaga...@gmail.com> >> --- >> libavutil/x86/lls.asm | 61 >> ++++++++++++++++++++++++++++++++++++++++++++++-- >> libavutil/x86/lls_init.c | 4 ++++ >> 2 files changed, 63 insertions(+), 2 deletions(-) >> >> diff --git a/libavutil/x86/lls.asm b/libavutil/x86/lls.asm >> index 769befb..925cbdb 100644 >> --- a/libavutil/x86/lls.asm >> +++ b/libavutil/x86/lls.asm >> @@ -125,8 +125,7 @@ cglobal update_lls, 2,5,8, ctx, var, i, j, covar2 >> .ret: >> REP_RET >> >> -%if HAVE_AVX_EXTERNAL >> -INIT_YMM avx >> +%macro UPDATE_LLS 0 >> cglobal update_lls, 3,6,8, ctx, var, count, i, j, count2 >> %define covarq ctxq >> mov countd, [ctxq + LLSModel.indep_count] >> @@ -140,6 +139,18 @@ cglobal update_lls, 3,6,8, ctx, var, count, i, j, count2 >> vbroadcastsd ymm6, [varq + iq*8 + 16] >> vbroadcastsd ymm7, [varq + iq*8 + 24] >> vextractf128 xmm3, ymm1, 1 >> +%if cpuflag(fma3) >> + mova ymm0, COVAR(iq ,0) >> + mova xmm2, COVAR(iq+2,2) >> + fmaddpd ymm0, ymm1, ymm4, ymm0 >> + fmaddpd xmm2, xmm3, xmm6, xmm2 >> + fmaddpd ymm1, ymm5, ymm1, COVAR(iq ,1) >> + fmaddpd xmm3, xmm7, xmm3, COVAR(iq+2,3) >> + mova COVAR(iq ,0), ymm0 >> + mova COVAR(iq ,1), ymm1 >> + mova COVAR(iq+2,2), xmm2 >> + mova COVAR(iq+2,3), xmm3 >> +%else >> vmulpd ymm0, ymm1, ymm4 >> vmulpd ymm1, ymm1, ymm5 >> vmulpd xmm2, xmm3, xmm6 >> @@ -148,12 +159,27 @@ cglobal update_lls, 3,6,8, ctx, var, count, i, j, >> count2 >> ADDPD_MEM COVAR(iq ,1), ymm1 >> ADDPD_MEM COVAR(iq+2,2), xmm2 >> ADDPD_MEM COVAR(iq+2,3), xmm3 >> +%endif ; cpuflag(fma3) >> lea jd, [iq + 4] >> cmp jd, count2d >> jg .skip4x4 >> .loop4x4: >> ; Compute all 16 pairwise products of a 4x4 block >> mova ymm3, [varq + jq*8] >> +%if cpuflag(fma3) >> + mova ymm0, COVAR(jq, 0) >> + mova ymm1, COVAR(jq, 1) >> + mova ymm2, COVAR(jq, 2) >> + mova ymm3, COVAR(jq, 3) > > This is wrong. You're overwriting the contents of ymm3. libavutil/lls-test > didn't reflect > this at all? > >> + fmaddpd ymm0, ymm3, ymm4, ymm0 >> + fmaddpd ymm1, ymm3, ymm5, ymm1 >> + fmaddpd ymm2, ymm3, ymm6, ymm2 >> + fmaddpd ymm3, ymm3, ymm7, ymm3 >> + mova COVAR(jq, 0), ymm0 >> + mova COVAR(jq, 1), ymm1 >> + mova COVAR(jq, 2), ymm2 >> + mova COVAR(jq, 3), ymm3 >> +%else >> vmulpd ymm0, ymm3, ymm4 >> vmulpd ymm1, ymm3, ymm5 >> vmulpd ymm2, ymm3, ymm6 >> @@ -162,6 +188,7 @@ cglobal update_lls, 3,6,8, ctx, var, count, i, j, count2 >> ADDPD_MEM COVAR(jq,1), ymm1 >> ADDPD_MEM COVAR(jq,2), ymm2 >> ADDPD_MEM COVAR(jq,3), ymm3 >> +%endif ; cpuflag(fma3) >> add jd, 4 >> cmp jd, count2d >> jle .loop4x4 >> @@ -169,6 +196,20 @@ cglobal update_lls, 3,6,8, ctx, var, count, i, j, count2 >> cmp jd, countd >> jg .skip2x4 >> mova xmm3, [varq + jq*8] >> +%if cpuflag(fma3) >> + mova xmm0, COVAR(jq, 0) >> + mova xmm1, COVAR(jq, 1) >> + mova xmm2, COVAR(jq, 2) >> + mova xmm3, COVAR(jq, 3) > > Same here.
Diff /tmp/lls.old /tmp/lls.new: < real:-0.326534 order:0 pred:-0.588792 var:0.272632 coeffs:1.427836 -0.385559 0.000000 < real:-0.326534 order:1 pred:-0.326534 var:-nan coeffs:3.274787 -1.436430 0.000000 < real:-0.326534 order:2 pred:-0.326534 var:0.000000 coeffs:3.274787 -1.436430 0.000000 --- > real:-0.326534 order:0 pred:-0.588792 var:0.272632 coeffs:1.427836 -0.385559 > -0.000000 > real:-0.326534 order:1 pred:-0.326534 var:0.000000 coeffs:3.274787 -1.436430 > 0.000000 > real:-0.326534 order:2 pred:-0.326534 var:-nan coeffs:3.274787 -1.436430 > -0.000000 You are definitely right, though. Removed 2 lines: mova ymm3, COVAR(jq,3) and mova xmm3, COVAR(jq,2) > > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
