[FFmpeg-devel] [PATCH] mdct15: add assembly optimizations for the 15-point FFT
Rostislav Pehlivanov
atomnuker at gmail.com
Thu Jun 22 01:33:25 EEST 2017
fft15_c: 1961 decicycles in fft15, 4193738 runs, 566 skips
fft15_fma3: 995 decicycles in fft15, 4193984 runs, 320 skips
I believe the FFT5 macro can be improved further, so suggestions
are welcome.
---
libavcodec/mdct15.c | 186 +++++++++++++++++++++----------------------
libavcodec/mdct15.h | 26 +++---
libavcodec/x86/Makefile | 2 +
libavcodec/x86/mdct15.asm | 149 ++++++++++++++++++++++++++++++++++
libavcodec/x86/mdct15_init.c | 93 ++++++++++++++++++++++
5 files changed, 345 insertions(+), 111 deletions(-)
create mode 100644 libavcodec/x86/mdct15.asm
create mode 100644 libavcodec/x86/mdct15_init.c
diff --git a/libavcodec/mdct15.c b/libavcodec/mdct15.c
index 8c42ece483..0cf734caf9 100644
--- a/libavcodec/mdct15.c
+++ b/libavcodec/mdct15.c
@@ -57,11 +57,6 @@ av_cold void ff_mdct15_uninit(MDCT15Context **ps)
av_freep(ps);
}
-static void mdct15(MDCT15Context *s, float *dst, const float *src, ptrdiff_t stride);
-
-static void imdct15_half(MDCT15Context *s, float *dst, const float *src,
- ptrdiff_t stride, float scale);
-
static inline int init_pfa_reindex_tabs(MDCT15Context *s)
{
int i, j;
@@ -93,88 +88,8 @@ static inline int init_pfa_reindex_tabs(MDCT15Context *s)
return 0;
}
-av_cold int ff_mdct15_init(MDCT15Context **ps, int inverse, int N, double scale)
-{
- MDCT15Context *s;
- double alpha, theta;
- int len2 = 15 * (1 << N);
- int len = 2 * len2;
- int i;
-
- /* Tested and verified to work on everything in between */
- if ((N < 2) || (N > 13))
- return AVERROR(EINVAL);
-
- s = av_mallocz(sizeof(*s));
- if (!s)
- return AVERROR(ENOMEM);
-
- s->fft_n = N - 1;
- s->len4 = len2 / 2;
- s->len2 = len2;
- s->inverse = inverse;
- s->mdct = mdct15;
- s->imdct_half = imdct15_half;
-
- if (ff_fft_init(&s->ptwo_fft, N - 1, s->inverse) < 0)
- goto fail;
-
- if (init_pfa_reindex_tabs(s))
- goto fail;
-
- s->tmp = av_malloc_array(len, 2 * sizeof(*s->tmp));
- if (!s->tmp)
- goto fail;
-
- s->twiddle_exptab = av_malloc_array(s->len4, sizeof(*s->twiddle_exptab));
- if (!s->twiddle_exptab)
- goto fail;
-
- theta = 0.125f + (scale < 0 ? s->len4 : 0);
- scale = sqrt(fabs(scale));
- for (i = 0; i < s->len4; i++) {
- alpha = 2 * M_PI * (i + theta) / len;
- s->twiddle_exptab[i].re = cos(alpha) * scale;
- s->twiddle_exptab[i].im = sin(alpha) * scale;
- }
-
- /* 15-point FFT exptab */
- for (i = 0; i < 19; i++) {
- if (i < 15) {
- double theta = (2.0f * M_PI * i) / 15.0f;
- if (!s->inverse)
- theta *= -1;
- s->exptab[i].re = cos(theta);
- s->exptab[i].im = sin(theta);
- } else { /* Wrap around to simplify fft15 */
- s->exptab[i] = s->exptab[i - 15];
- }
- }
-
- /* 5-point FFT exptab */
- s->exptab[19].re = cos(2.0f * M_PI / 5.0f);
- s->exptab[19].im = sin(2.0f * M_PI / 5.0f);
- s->exptab[20].re = cos(1.0f * M_PI / 5.0f);
- s->exptab[20].im = sin(1.0f * M_PI / 5.0f);
-
- /* Invert the phase for an inverse transform, do nothing for a forward transform */
- if (s->inverse) {
- s->exptab[19].im *= -1;
- s->exptab[20].im *= -1;
- }
-
- *ps = s;
-
- return 0;
-
-fail:
- ff_mdct15_uninit(&s);
- return AVERROR(ENOMEM);
-}
-
/* Stride is hardcoded to 3 */
-static inline void fft5(const FFTComplex exptab[2], FFTComplex *out,
- const FFTComplex *in)
+static inline void fft5(FFTComplex *out, FFTComplex *in, FFTComplex exptab[2])
{
FFTComplex z0[4], t[6];
@@ -219,14 +134,14 @@ static inline void fft5(const FFTComplex exptab[2], FFTComplex *out,
out[4].im = in[0].im + z0[3].im;
}
-static void fft15(const FFTComplex exptab[22], FFTComplex *out, const FFTComplex *in, size_t stride)
+static void fft15(FFTComplex *out, FFTComplex *in, FFTComplex *exptab, size_t stride)
{
int k;
FFTComplex tmp1[5], tmp2[5], tmp3[5];
- fft5(exptab + 19, tmp1, in + 0);
- fft5(exptab + 19, tmp2, in + 1);
- fft5(exptab + 19, tmp3, in + 2);
+ fft5(tmp1, in + 0, exptab + 19);
+ fft5(tmp2, in + 1, exptab + 19);
+ fft5(tmp3, in + 2, exptab + 19);
for (k = 0; k < 5; k++) {
FFTComplex t[2];
@@ -253,10 +168,10 @@ static void mdct15(MDCT15Context *s, float *dst, const float *src, ptrdiff_t str
int i, j;
const int len4 = s->len4, len3 = len4 * 3, len8 = len4 >> 1;
const int l_ptwo = 1 << s->ptwo_fft.nbits;
- FFTComplex fft15in[15];
/* Folding and pre-reindexing */
for (i = 0; i < l_ptwo; i++) {
+ DECLARE_ALIGNED(32, FFTComplex, fft15in)[32];
for (j = 0; j < 15; j++) {
float re, im;
const int k = s->pfa_prereindex[i*15 + j];
@@ -269,7 +184,7 @@ static void mdct15(MDCT15Context *s, float *dst, const float *src, ptrdiff_t str
}
CMUL(fft15in[j].re, fft15in[j].im, re, im, s->twiddle_exptab[k].re, -s->twiddle_exptab[k].im);
}
- fft15(s->exptab, s->tmp + s->ptwo_fft.revtab[i], fft15in, l_ptwo);
+ s->fft15(s->tmp + s->ptwo_fft.revtab[i], fft15in, s->exptab, l_ptwo);
}
/* Then a 15xN FFT (where N is a power of two) */
@@ -294,19 +209,19 @@ static void mdct15(MDCT15Context *s, float *dst, const float *src, ptrdiff_t str
static void imdct15_half(MDCT15Context *s, float *dst, const float *src,
ptrdiff_t stride, float scale)
{
- FFTComplex fft15in[15];
FFTComplex *z = (FFTComplex *)dst;
int i, j, len8 = s->len4 >> 1, l_ptwo = 1 << s->ptwo_fft.nbits;
const float *in1 = src, *in2 = src + (s->len2 - 1) * stride;
/* Reindex input, putting it into a buffer and doing an Nx15 FFT */
for (i = 0; i < l_ptwo; i++) {
+ DECLARE_ALIGNED(32, FFTComplex, fft15in)[32];
for (j = 0; j < 15; j++) {
const int k = s->pfa_prereindex[i*15 + j];
FFTComplex tmp = { *(in2 - 2*k*stride), *(in1 + 2*k*stride) };
CMUL3(fft15in[j], tmp, s->twiddle_exptab[k]);
}
- fft15(s->exptab, s->tmp + s->ptwo_fft.revtab[i], fft15in, l_ptwo);
+ s->fft15(s->tmp + s->ptwo_fft.revtab[i], fft15in, s->exptab, l_ptwo);
}
/* Then a 15xN FFT (where N is a power of two) */
@@ -327,3 +242,86 @@ static void imdct15_half(MDCT15Context *s, float *dst, const float *src,
z[i0].im = scale * im1;
}
}
+
+av_cold int ff_mdct15_init(MDCT15Context **ps, int inverse, int N, double scale)
+{
+ MDCT15Context *s;
+ double alpha, theta;
+ int len2 = 15 * (1 << N);
+ int len = 2 * len2;
+ int i;
+
+ /* Tested and verified to work on everything in between */
+ if ((N < 2) || (N > 13))
+ return AVERROR(EINVAL);
+
+ s = av_mallocz(sizeof(*s));
+ if (!s)
+ return AVERROR(ENOMEM);
+
+ s->fft_n = N - 1;
+ s->len4 = len2 / 2;
+ s->len2 = len2;
+ s->inverse = inverse;
+ s->fft15 = fft15;
+ s->mdct = mdct15;
+ s->imdct_half = imdct15_half;
+
+ if (ff_fft_init(&s->ptwo_fft, N - 1, s->inverse) < 0)
+ goto fail;
+
+ if (init_pfa_reindex_tabs(s))
+ goto fail;
+
+ s->tmp = av_malloc_array(len, 2 * sizeof(*s->tmp));
+ if (!s->tmp)
+ goto fail;
+
+ s->twiddle_exptab = av_malloc_array(s->len4, sizeof(*s->twiddle_exptab));
+ if (!s->twiddle_exptab)
+ goto fail;
+
+ theta = 0.125f + (scale < 0 ? s->len4 : 0);
+ scale = sqrt(fabs(scale));
+ for (i = 0; i < s->len4; i++) {
+ alpha = 2 * M_PI * (i + theta) / len;
+ s->twiddle_exptab[i].re = cos(alpha) * scale;
+ s->twiddle_exptab[i].im = sin(alpha) * scale;
+ }
+
+ /* 15-point FFT exptab */
+ for (i = 0; i < 19; i++) {
+ if (i < 15) {
+ double theta = (2.0f * M_PI * i) / 15.0f;
+ if (!s->inverse)
+ theta *= -1;
+ s->exptab[i].re = cos(theta);
+ s->exptab[i].im = sin(theta);
+ } else { /* Wrap around to simplify fft15 */
+ s->exptab[i] = s->exptab[i - 15];
+ }
+ }
+
+ /* 5-point FFT exptab */
+ s->exptab[19].re = cos(2.0f * M_PI / 5.0f);
+ s->exptab[19].im = sin(2.0f * M_PI / 5.0f);
+ s->exptab[20].re = cos(1.0f * M_PI / 5.0f);
+ s->exptab[20].im = sin(1.0f * M_PI / 5.0f);
+
+ /* Invert the phase for an inverse transform, do nothing for a forward transform */
+ if (s->inverse) {
+ s->exptab[19].im *= -1;
+ s->exptab[20].im *= -1;
+ }
+
+ if (ARCH_X86)
+ ff_mdct15_init_x86(s);
+
+ *ps = s;
+
+ return 0;
+
+fail:
+ ff_mdct15_uninit(&s);
+ return AVERROR(ENOMEM);
+}
diff --git a/libavcodec/mdct15.h b/libavcodec/mdct15.h
index ef94edff6c..15a91220b6 100644
--- a/libavcodec/mdct15.h
+++ b/libavcodec/mdct15.h
@@ -34,34 +34,26 @@ typedef struct MDCT15Context {
int *pfa_postreindex;
FFTContext ptwo_fft;
-
FFTComplex *tmp;
-
FFTComplex *twiddle_exptab;
- /* 0 - 18: fft15 twiddles, 19 - 20: fft5 twiddles */
- FFTComplex exptab[21];
+ DECLARE_ALIGNED(32, FFTComplex, exptab)[64];
- /**
- * Calculate a full 2N -> N MDCT
- */
+ /* 15-point FFT */
+ void (*fft15)(FFTComplex *out, FFTComplex *in, FFTComplex *exptab, size_t stride);
+
+ /* Calculate a full 2N -> N MDCT */
void (*mdct)(struct MDCT15Context *s, float *dst, const float *src, ptrdiff_t stride);
- /**
- * Calculate the middle half of the iMDCT
- */
+ /* Calculate the middle half of the iMDCT */
void (*imdct_half)(struct MDCT15Context *s, float *dst, const float *src,
ptrdiff_t src_stride, float scale);
} MDCT15Context;
-/**
- * Init an (i)MDCT of the length 2 * 15 * (2^N)
- */
+/* Init an (i)MDCT of the length 2 * 15 * (2^N) */
int ff_mdct15_init(MDCT15Context **ps, int inverse, int N, double scale);
-
-/**
- * Frees a context
- */
void ff_mdct15_uninit(MDCT15Context **ps);
+void ff_mdct15_init_x86(MDCT15Context *s);
+
#endif /* AVCODEC_MDCT15_H */
diff --git a/libavcodec/x86/Makefile b/libavcodec/x86/Makefile
index e65118d134..12f6b84372 100644
--- a/libavcodec/x86/Makefile
+++ b/libavcodec/x86/Makefile
@@ -53,6 +53,7 @@ OBJS-$(CONFIG_DCA_DECODER) += x86/dcadsp_init.o x86/synth_filter_ini
OBJS-$(CONFIG_DNXHD_ENCODER) += x86/dnxhdenc_init.o
OBJS-$(CONFIG_HEVC_DECODER) += x86/hevcdsp_init.o
OBJS-$(CONFIG_JPEG2000_DECODER) += x86/jpeg2000dsp_init.o
+OBJS-$(CONFIG_MDCT15) += x86/mdct15_init.o
OBJS-$(CONFIG_MLP_DECODER) += x86/mlpdsp_init.o
OBJS-$(CONFIG_MPEG4_DECODER) += x86/xvididct_init.o
OBJS-$(CONFIG_PNG_DECODER) += x86/pngdsp_init.o
@@ -158,6 +159,7 @@ X86ASM-OBJS-$(CONFIG_HEVC_DECODER) += x86/hevc_add_res.o \
x86/hevc_sao.o \
x86/hevc_sao_10bit.o
X86ASM-OBJS-$(CONFIG_JPEG2000_DECODER) += x86/jpeg2000dsp.o
+X86ASM-OBJS-$(CONFIG_MDCT15) += x86/mdct15.o
X86ASM-OBJS-$(CONFIG_MLP_DECODER) += x86/mlpdsp.o
X86ASM-OBJS-$(CONFIG_MPEG4_DECODER) += x86/xvididct.o
X86ASM-OBJS-$(CONFIG_PNG_DECODER) += x86/pngdsp.o
diff --git a/libavcodec/x86/mdct15.asm b/libavcodec/x86/mdct15.asm
new file mode 100644
index 0000000000..437df7bea6
--- /dev/null
+++ b/libavcodec/x86/mdct15.asm
@@ -0,0 +1,149 @@
+;******************************************************************************
+;* SIMD optimized non-power of two MDCT functions
+;*
+;* Copyright (C) 2017 Rostislav Pehlivanov <atomnuker at gmail.com>
+;*
+;* This file is part of FFmpeg.
+;*
+;* FFmpeg is free software; you can redistribute it and/or
+;* modify it under the terms of the GNU Lesser General Public
+;* License as published by the Free Software Foundation; either
+;* version 2.1 of the License, or (at your option) any later version.
+;*
+;* FFmpeg is distributed in the hope that it will be useful,
+;* but WITHOUT ANY WARRANTY; without even the implied warranty of
+;* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+;* Lesser General Public License for more details.
+;*
+;* You should have received a copy of the GNU Lesser General Public
+;* License along with FFmpeg; if not, write to the Free Software
+;* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+;******************************************************************************
+
+%include "libavutil/x86/x86util.asm"
+
+SECTION_RODATA 32
+
+sign_adjust_5: times 2 dd 1.0, -1.0, -1.0, 1.0
+
+SECTION .text
+
+%macro FFT5 7 ; src, offset, dst1 (1/2 filled), dst2, exptab1, exptab2, signadjust (uses m0-m4)
+ movddup xm0, [%1q + 0*16 + 0 + %2] ; in[ 0].re, in[ 0].im, in[ 1].re, in[ 1].im
+ movsd xm1, [%1q + 1*16 + 8 + %2] ; in[ 3].re, in[ 3].im, in[ 4].re, in[ 4].im
+ movups xm2, [%1q + 2*16 + 8 + %2] ; in[ 5].re, in[ 5].im, in[ 6].re, in[ 6].im
+ movups xm3, [%1q + 4*16 + 0 + %2] ; in[ 8].re, in[ 8].im, in[ 9].re, in[ 9].im
+ movsd xm4, [%1q + 6*16 + 0 + %2] ; in[12].re, in[12].im, in[13].re, in[13].im
+
+ shufps xm1, xm2, q3210 ; in[ 3].re, in[ 3].im, in[ 6].re, in[ 6].im
+ shufps xm4, xm3, q3210 ; in[12].re, in[12].im, in[ 9].re, in[ 9].im
+
+ subps xm2, xm1, xm4 ; t[2].im, t[2].re, t[3].im, t[3].re
+ addps xm1, xm4 ; t[0].re, t[0].im, t[1].re, t[1].im
+
+ shufps %3, xm1, xm1, q3120 ; t[0].re, t[1].re, t[0].im, t[1].im
+ haddps %3, xm4
+ addps %3, xm0 ; DC[0].re, DC[0].im, junk...
+ movlhps %3, %3 ; DC[0].re, DC[0].im, DC[0].re, DC[0].im
+
+ shufps xm3, xm1, xm2, q0110 ; t[0].re, t[0].im, t[2].re, t[2].im
+ shufps xm1, xm2, q2332 ; t[1].re, t[1].im, t[3].re, t[3].im
+
+ mulps xm%4, xm1, %5
+ mulps xm4, xm3, %6
+ mulps xm1, %6
+
+ mulps xm1, %7
+ fmaddsubps xm3, xm3, %5, xm1 ; t[0].re, t[0].im, t[2].re, t[2].im
+ subps xm%4, xm4 ; t[4].re, t[4].im, t[5].re, t[5].im
+
+ mova xm4, %7
+
+ unpckhpd xm2, xm3, xm%4 ; t[2].re, t[2].im, t[5].re, t[5].im
+ unpcklpd xm3, xm%4 ; t[0].re, t[0].im, t[4].re, t[4].im
+
+ mova xm%4, xm4
+ fmaddps xm%4, xm2, xm%4, xm3
+ addps xm%4, xm0 ; ACs(1)
+
+ fnmaddps xm2, xm2, xm4, xm3
+ shufps xm2, xm2, q1032
+ addps xm2, xm0 ; ACs(2)
+ vinsertf128 m%4, m%4, xm2, 1 ; All ACs (tmp[1] through to tmp[4])
+%endmacro
+
+%macro BUTTERFLIES_DC 7 ; exptab, exptab_offset, src1, src2, src3, out, out_offset, (uses m0-m1)
+ movaps m0, [%1q + %2]
+ vextractf128 xm1, m0, 1
+
+ mulps xm1, %5
+ mulps xm0, %4
+
+ haddps xm0, xm1
+ shufps xm0, xm0, q3120 ; t[0].re, t[1].re, t[0].im, t[1].im
+
+ haddps xm0, xm0
+ addps xm0, %3
+
+ movsd [%6q + %7], xm0
+%endmacro
+
+%macro BUTTERFLIES_AC 8 ; exptab, exptab_offset, src1, src2, src3, out, strideq, k_off
+ mulps m0, %4, [%1q + 64*0 + 0*mmsize + %2]
+ mulps m1, %4, [%1q + 64*0 + 1*mmsize + %2]
+ mulps m2, %5, [%1q + 64*1 + 0*mmsize + %2]
+ mulps m3, %5, [%1q + 64*1 + 1*mmsize + %2]
+
+ shufps m1, m1, q2301
+ shufps m3, m3, q2301
+
+ addps m0, m1
+ addps m2, m3
+ addps m0, m2
+ addps m0, %3
+
+ vextractf128 xmm1, m0, 1
+
+ mov r5q, %8
+ add r5q, strideq
+ movlps [%6q + r5q], xmm0
+
+ add r5q, strideq
+ movhps [%6q + r5q], xmm0
+
+ add r5q, strideq
+ movlps [%6q + r5q], xmm1
+
+ add r5q, strideq
+ movhps [%6q + r5q], xmm1
+%endmacro
+
+;***************************************************************************************
+;void ff_fft15_fma3(FFTComplex *out, FFTComplex *in, FFTComplex *exptab, size_t stride);
+;***************************************************************************************
+INIT_YMM fma3
+cglobal fft15, 4, 6, 14, out, in, exptab, stride
+
+ shl strideq, 3
+
+ movaps m5, [exptabq + 480]
+ vextractf128 xm6, m5, 1
+ movaps xm7, [sign_adjust_5]
+
+ FFT5 in, 0, xm8, 11, xm5, xm6, xm7
+ FFT5 in, 8, xm9, 12, xm5, xm6, xm7
+ FFT5 in, 16, xm10, 13, xm5, xm6, xm7
+
+ BUTTERFLIES_DC exptab, (8*6 + 4*0)*2*4, xm8, xm9, xm10, out, 0
+ imul r4q, strideq, 5
+ BUTTERFLIES_DC exptab, (8*6 + 4*1)*2*4, xm8, xm9, xm10, out, r4q
+ imul r4q, 2 ; stride * 10
+ BUTTERFLIES_DC exptab, (8*6 + 4*2)*2*4, xm8, xm9, xm10, out, r4q
+
+ BUTTERFLIES_AC exptab, (8*0)*2*4, m11, m12, m13, out, strideq, 0
+ imul r4q, strideq, 5
+ BUTTERFLIES_AC exptab, (8*2)*2*4, m11, m12, m13, out, strideq, r4q
+ imul r4q, 2 ; stride * 10
+ BUTTERFLIES_AC exptab, (8*4)*2*4, m11, m12, m13, out, strideq, r4q
+
+ RET
diff --git a/libavcodec/x86/mdct15_init.c b/libavcodec/x86/mdct15_init.c
new file mode 100644
index 0000000000..16306b893f
--- /dev/null
+++ b/libavcodec/x86/mdct15_init.c
@@ -0,0 +1,93 @@
+/*
+ * Non power of two MDCT assembly optimizations
+ * Copyright (C) 2017 Rostislav Pehlivanov <atomnuker at gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "config.h"
+
+#include "libavutil/float_dsp.h"
+#include "libavutil/x86/cpu.h"
+#include "libavcodec/mdct15.h"
+
+void ff_fft15_fma3(FFTComplex *out, FFTComplex *in, FFTComplex *exptab, size_t stride);
+
+static void perm_twiddles(MDCT15Context *s)
+{
+ int k;
+
+ FFTComplex tmp[64], tmp2[64];
+ memcpy(tmp, s->exptab, sizeof(FFTComplex)*32);
+
+ /* 15-point FFT twiddles */
+ for (k = 0; k < 5; k++) {
+ tmp2[6*k + 0] = tmp[k + 0];
+ tmp2[6*k + 2] = tmp[k + 5];
+ tmp2[6*k + 4] = tmp[k + 10];
+
+ tmp2[6*k + 1] = tmp[2 * (k + 0)];
+ tmp2[6*k + 3] = tmp[2 * (k + 5)];
+ tmp2[6*k + 5] = tmp[2 * k + 5 ];
+ }
+
+ /* Newtab */
+
+ for (k = 0; k < 6; k++) {
+ FFTComplex ac_exp[] = {
+ { tmp2[6*1 + k].re, tmp2[6*1 + k].re },
+ { tmp2[6*2 + k].re, tmp2[6*2 + k].re },
+ { tmp2[6*3 + k].re, tmp2[6*3 + k].re },
+ { tmp2[6*4 + k].re, tmp2[6*4 + k].re },
+ { tmp2[6*1 + k].im, -tmp2[6*1 + k].im },
+ { tmp2[6*2 + k].im, -tmp2[6*2 + k].im },
+ { tmp2[6*3 + k].im, -tmp2[6*3 + k].im },
+ { tmp2[6*4 + k].im, -tmp2[6*4 + k].im },
+ };
+ memcpy(s->exptab + 8*k, ac_exp, 8*sizeof(FFTComplex));
+ }
+
+ /* Specialcase when k = 0 */
+ for (k = 0; k < 3; k++) {
+ FFTComplex dc_exp[] = {
+ { tmp2[2*k + 0].re, -tmp2[2*k + 0].im },
+ { tmp2[2*k + 0].im, tmp2[2*k + 0].re },
+ { tmp2[2*k + 1].re, -tmp2[2*k + 1].im },
+ { tmp2[2*k + 1].im, tmp2[2*k + 1].re },
+ };
+ memcpy(s->exptab + 8*6 + 4*k, dc_exp, 4*sizeof(FFTComplex));
+ }
+
+ /* 5-point FFT twiddles */
+ FFTComplex exp_5point[] = {
+ { tmp[19].re, tmp[19].re },
+ { tmp[19].im, tmp[19].im },
+ { tmp[20].re, tmp[20].re },
+ { tmp[20].im, tmp[20].im },
+ };
+ memcpy(s->exptab + 8*6 + 4*3, exp_5point, 4*sizeof(FFTComplex));
+}
+
+av_cold void ff_mdct15_init_x86(MDCT15Context *s)
+{
+ int cpu_flags = av_get_cpu_flags();
+
+ if (ARCH_X86_64 && EXTERNAL_FMA3(cpu_flags)) {
+ perm_twiddles(s);
+ s->fft15 = ff_fft15_fma3;
+ }
+}
--
2.13.1.611.g7e3b11ae1
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