On 1/14/2016 9:06 PM, Ganesh Ajjanagadde wrote: > On Thu, Jan 14, 2016 at 6:54 PM, Ganesh Ajjanagadde <gajja...@mit.edu> wrote: >> 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) > > Still buggy. Will calmly examine this some time.
You also need to use COVAR(jq, #) as the fourth argument for the two fmaddpd, like you did in .loopi _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
