x86/synth_filter: improve FMA version

Replace mulps+subps with fnmaddps, resulting in two less instructions inside the
inner loops.
About 1% faster FMA3 performance.

Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
pull/293/head
James Almer 11 years ago committed by Michael Niedermayer
parent e10ab43614
commit aa1f38015c
  1. 42
      libavcodec/x86/dcadsp.asm

@ -230,14 +230,27 @@ DCA_LFE_FIR 1
SHUF m11, ptr2 + j + (15 - 3) * 4 - mmsize, m12
mova m12, [ptr1 + j + mmsize]
%endif
FMULADD_PS m2, m6, [win + %1 + j + 16 * 4], m2, m6
%if cpuflag(fma3)
fmaddps m2, m6, [win + %1 + j + 16 * 4], m2
fnmaddps m1, m5, [win + %1 + j], m1
%if ARCH_X86_64
fmaddps m8, m12, [win + %1 + j + mmsize + 16 * 4], m8
fnmaddps m7, m11, [win + %1 + j + mmsize], m7
%endif
%else ; non-FMA
mulps m6, m6, [win + %1 + j + 16 * 4]
mulps m5, m5, [win + %1 + j]
subps m1, m1, m5
%if ARCH_X86_64
FMULADD_PS m8, m12, [win + %1 + j + mmsize + 16 * 4], m8, m12
mulps m12, m12, [win + %1 + j + mmsize + 16 * 4]
mulps m11, m11, [win + %1 + j + mmsize]
%endif
addps m2, m2, m6
subps m1, m1, m5
%if ARCH_X86_64
addps m8, m8, m12
subps m7, m7, m11
%endif
%endif ; cpuflag(fma3)
;~ c += window[i + j + 32] * (synth_buf[16 + i + j])
;~ d += window[i + j + 48] * (synth_buf[31 - i + j])
SHUF m6, ptr2 + j + (31 - 3) * 4, m5
@ -246,12 +259,27 @@ DCA_LFE_FIR 1
SHUF m12, ptr2 + j + (31 - 3) * 4 - mmsize, m11
mova m11, [ptr1 + j + mmsize + 16 * 4]
%endif
FMULADD_PS m3, m5, [win + %1 + j + 32 * 4], m3, m5
FMULADD_PS m4, m6, [win + %1 + j + 48 * 4], m4, m6
%if cpuflag(fma3)
fmaddps m3, m5, [win + %1 + j + 32 * 4], m3
fmaddps m4, m6, [win + %1 + j + 48 * 4], m4
%if ARCH_X86_64
fmaddps m9, m11, [win + %1 + j + mmsize + 32 * 4], m9
fmaddps m10, m12, [win + %1 + j + mmsize + 48 * 4], m10
%endif
%else ; non-FMA
mulps m5, m5, [win + %1 + j + 32 * 4]
mulps m6, m6, [win + %1 + j + 48 * 4]
%if ARCH_X86_64
mulps m11, m11, [win + %1 + j + mmsize + 32 * 4]
mulps m12, m12, [win + %1 + j + mmsize + 48 * 4]
%endif
addps m3, m3, m5
addps m4, m4, m6
%if ARCH_X86_64
FMULADD_PS m9, m11, [win + %1 + j + mmsize + 32 * 4], m9, m11
FMULADD_PS m10, m12, [win + %1 + j + mmsize + 48 * 4], m10, m12
addps m9, m9, m11
addps m10, m10, m12
%endif
%endif ; cpuflag(fma3)
sub j, 64 * 4
%endmacro

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