FFmpeg coverage

GCC Code Coverage Report

Directory:	../../../ffmpeg/		Exec	Total	Coverage
File:	src/libavcodec/fft_template.c	Lines:	257	277	92.8 %
Date:	2021-01-21 21:11:50	Branches:	60	78	76.9 %


/*
 * FFT/IFFT transforms
 * Copyright (c) 2008 Loren Merritt
 * Copyright (c) 2002 Fabrice Bellard
 * Partly based on libdjbfft by D. J. Bernstein
 *
 * 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
 */

/**
 * @file
 * FFT/IFFT transforms.
 */

#include <stdlib.h>
#include <string.h>
#include "libavutil/mathematics.h"
#include "libavutil/thread.h"
#include "fft.h"
#include "fft-internal.h"

#if FFT_FIXED_32
#include "fft_table.h"
#else /* FFT_FIXED_32 */

/* cos(2*pi*x/n) for 0<=x<=n/4, followed by its reverse */
#if !CONFIG_HARDCODED_TABLES
COSTABLE(16);
COSTABLE(32);
COSTABLE(64);
COSTABLE(128);
COSTABLE(256);
COSTABLE(512);
COSTABLE(1024);
COSTABLE(2048);
COSTABLE(4096);
COSTABLE(8192);
COSTABLE(16384);
COSTABLE(32768);
COSTABLE(65536);
COSTABLE(131072);

static av_cold void init_ff_cos_tabs(int index)
{
    int i;
    int m = 1<<index;
    double freq = 2*M_PI/m;
    FFTSample *tab = FFT_NAME(ff_cos_tabs)[index];
    for(i=0; i<=m/4; i++)
        tab[i] = FIX15(cos(i*freq));
    for(i=1; i<m/4; i++)
        tab[m/2-i] = tab[i];
}

typedef struct CosTabsInitOnce {
    void (*func)(void);
    AVOnce control;
} CosTabsInitOnce;

#define INIT_FF_COS_TABS_FUNC(index, size)          \
static av_cold void init_ff_cos_tabs_ ## size (void)\
{                                                   \
    init_ff_cos_tabs(index);                        \
}

INIT_FF_COS_TABS_FUNC(4, 16)
INIT_FF_COS_TABS_FUNC(5, 32)
INIT_FF_COS_TABS_FUNC(6, 64)
INIT_FF_COS_TABS_FUNC(7, 128)
INIT_FF_COS_TABS_FUNC(8, 256)
INIT_FF_COS_TABS_FUNC(9, 512)
INIT_FF_COS_TABS_FUNC(10, 1024)
INIT_FF_COS_TABS_FUNC(11, 2048)
INIT_FF_COS_TABS_FUNC(12, 4096)
INIT_FF_COS_TABS_FUNC(13, 8192)
INIT_FF_COS_TABS_FUNC(14, 16384)
INIT_FF_COS_TABS_FUNC(15, 32768)
INIT_FF_COS_TABS_FUNC(16, 65536)
INIT_FF_COS_TABS_FUNC(17, 131072)

static CosTabsInitOnce cos_tabs_init_once[] = {
    { NULL },
    { NULL },
    { NULL },
    { NULL },
    { init_ff_cos_tabs_16, AV_ONCE_INIT },
    { init_ff_cos_tabs_32, AV_ONCE_INIT },
    { init_ff_cos_tabs_64, AV_ONCE_INIT },
    { init_ff_cos_tabs_128, AV_ONCE_INIT },
    { init_ff_cos_tabs_256, AV_ONCE_INIT },
    { init_ff_cos_tabs_512, AV_ONCE_INIT },
    { init_ff_cos_tabs_1024, AV_ONCE_INIT },
    { init_ff_cos_tabs_2048, AV_ONCE_INIT },
    { init_ff_cos_tabs_4096, AV_ONCE_INIT },
    { init_ff_cos_tabs_8192, AV_ONCE_INIT },
    { init_ff_cos_tabs_16384, AV_ONCE_INIT },
    { init_ff_cos_tabs_32768, AV_ONCE_INIT },
    { init_ff_cos_tabs_65536, AV_ONCE_INIT },
    { init_ff_cos_tabs_131072, AV_ONCE_INIT },
};

#endif
COSTABLE_CONST FFTSample * const FFT_NAME(ff_cos_tabs)[] = {
    NULL, NULL, NULL, NULL,
    FFT_NAME(ff_cos_16),
    FFT_NAME(ff_cos_32),
    FFT_NAME(ff_cos_64),
    FFT_NAME(ff_cos_128),
    FFT_NAME(ff_cos_256),
    FFT_NAME(ff_cos_512),
    FFT_NAME(ff_cos_1024),
    FFT_NAME(ff_cos_2048),
    FFT_NAME(ff_cos_4096),
    FFT_NAME(ff_cos_8192),
    FFT_NAME(ff_cos_16384),
    FFT_NAME(ff_cos_32768),
    FFT_NAME(ff_cos_65536),
    FFT_NAME(ff_cos_131072),
};

#endif /* FFT_FIXED_32 */

static void fft_permute_c(FFTContext *s, FFTComplex *z);
static void fft_calc_c(FFTContext *s, FFTComplex *z);

static int split_radix_permutation(int i, int n, int inverse)
{
    int m;
    if(n <= 2) return i&1;
    m = n >> 1;
    if(!(i&m))            return split_radix_permutation(i, m, inverse)*2;
    m >>= 1;
    if(inverse == !(i&m)) return split_radix_permutation(i, m, inverse)*4 + 1;
    else                  return split_radix_permutation(i, m, inverse)*4 - 1;
}

av_cold void ff_init_ff_cos_tabs(int index)
{
#if (!CONFIG_HARDCODED_TABLES) && (!FFT_FIXED_32)
    ff_thread_once(&cos_tabs_init_once[index].control, cos_tabs_init_once[index].func);
#endif
}

static const int avx_tab[] = {
    0, 4, 1, 5, 8, 12, 9, 13, 2, 6, 3, 7, 10, 14, 11, 15
};

static int is_second_half_of_fft32(int i, int n)
{
    if (n <= 32)
        return i >= 16;
    else if (i < n/2)
        return is_second_half_of_fft32(i, n/2);
    else if (i < 3*n/4)
        return is_second_half_of_fft32(i - n/2, n/4);
    else
        return is_second_half_of_fft32(i - 3*n/4, n/4);
}

static av_cold void fft_perm_avx(FFTContext *s)
{
    int i;
    int n = 1 << s->nbits;

    for (i = 0; i < n; i += 16) {
        int k;
        if (is_second_half_of_fft32(i, n)) {
            for (k = 0; k < 16; k++)
                s->revtab[-split_radix_permutation(i + k, n, s->inverse) & (n - 1)] =
                    i + avx_tab[k];

        } else {
            for (k = 0; k < 16; k++) {
                int j = i + k;
                j = (j & ~7) | ((j >> 1) & 3) | ((j << 2) & 4);
                s->revtab[-split_radix_permutation(i + k, n, s->inverse) & (n - 1)] = j;
            }
        }
    }
}

av_cold int ff_fft_init(FFTContext *s, int nbits, int inverse)
{
    int i, j, n;

    s->revtab = NULL;
    s->revtab32 = NULL;

    if (nbits < 2 || nbits > 17)
        goto fail;
    s->nbits = nbits;
    n = 1 << nbits;

    if (nbits <= 16) {
        s->revtab = av_malloc(n * sizeof(uint16_t));
        if (!s->revtab)
            goto fail;
    } else {
        s->revtab32 = av_malloc(n * sizeof(uint32_t));
        if (!s->revtab32)
            goto fail;
    }
    s->tmp_buf = av_malloc(n * sizeof(FFTComplex));
    if (!s->tmp_buf)
        goto fail;
    s->inverse = inverse;
    s->fft_permutation = FF_FFT_PERM_DEFAULT;

    s->fft_permute = fft_permute_c;
    s->fft_calc    = fft_calc_c;
#if CONFIG_MDCT
    s->imdct_calc  = ff_imdct_calc_c;
    s->imdct_half  = ff_imdct_half_c;
    s->mdct_calc   = ff_mdct_calc_c;
#endif

#if FFT_FIXED_32
    ff_fft_lut_init();
#else /* FFT_FIXED_32 */
#if FFT_FLOAT
    if (ARCH_AARCH64) ff_fft_init_aarch64(s);
    if (ARCH_ARM)     ff_fft_init_arm(s);
    if (ARCH_PPC)     ff_fft_init_ppc(s);
    if (ARCH_X86)     ff_fft_init_x86(s);
    if (HAVE_MIPSFPU) ff_fft_init_mips(s);
#endif
    for(j=4; j<=nbits; j++) {
        ff_init_ff_cos_tabs(j);
    }
#endif /* FFT_FIXED_32 */


    if (ARCH_X86 && FFT_FLOAT && s->fft_permutation == FF_FFT_PERM_AVX) {
        fft_perm_avx(s);
    } else {
#define PROCESS_FFT_PERM_SWAP_LSBS(num) do {\
    for(i = 0; i < n; i++) {\
        int k;\
        j = i;\
        j = (j & ~3) | ((j >> 1) & 1) | ((j << 1) & 2);\
        k = -split_radix_permutation(i, n, s->inverse) & (n - 1);\
        s->revtab##num[k] = j;\
    } \
} while(0);

#define PROCESS_FFT_PERM_DEFAULT(num) do {\
    for(i = 0; i < n; i++) {\
        int k;\
        j = i;\
        k = -split_radix_permutation(i, n, s->inverse) & (n - 1);\
        s->revtab##num[k] = j;\
    } \
} while(0);

#define SPLIT_RADIX_PERMUTATION(num) do { \
    if (s->fft_permutation == FF_FFT_PERM_SWAP_LSBS) {\
        PROCESS_FFT_PERM_SWAP_LSBS(num) \
    } else {\
        PROCESS_FFT_PERM_DEFAULT(num) \
    }\
} while(0);

    if (s->revtab)
        SPLIT_RADIX_PERMUTATION()
    if (s->revtab32)
        SPLIT_RADIX_PERMUTATION(32)

#undef PROCESS_FFT_PERM_DEFAULT
#undef PROCESS_FFT_PERM_SWAP_LSBS
#undef SPLIT_RADIX_PERMUTATION
    }

    return 0;
 fail:
    av_freep(&s->revtab);
    av_freep(&s->revtab32);
    av_freep(&s->tmp_buf);
    return -1;
}

static void fft_permute_c(FFTContext *s, FFTComplex *z)
{
    int j, np;
    const uint16_t *revtab = s->revtab;
    const uint32_t *revtab32 = s->revtab32;
    np = 1 << s->nbits;
    /* TODO: handle split-radix permute in a more optimal way, probably in-place */
    if (revtab) {
        for(j=0;j<np;j++) s->tmp_buf[revtab[j]] = z[j];
    } else
        for(j=0;j<np;j++) s->tmp_buf[revtab32[j]] = z[j];

    memcpy(z, s->tmp_buf, np * sizeof(FFTComplex));
}

av_cold void ff_fft_end(FFTContext *s)
{
    av_freep(&s->revtab);
    av_freep(&s->revtab32);
    av_freep(&s->tmp_buf);
}

#if FFT_FIXED_32

static void fft_calc_c(FFTContext *s, FFTComplex *z) {

    int nbits, i, n, num_transforms, offset, step;
    int n4, n2, n34;
    unsigned tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7, tmp8;
    FFTComplex *tmpz;
    const int fft_size = (1 << s->nbits);
    int64_t accu;

    num_transforms = (0x2aab >> (16 - s->nbits)) | 1;

    for (n=0; n<num_transforms; n++){
        offset = ff_fft_offsets_lut[n] << 2;
        tmpz = z + offset;

        tmp1 = tmpz[0].re + (unsigned)tmpz[1].re;
        tmp5 = tmpz[2].re + (unsigned)tmpz[3].re;
        tmp2 = tmpz[0].im + (unsigned)tmpz[1].im;
        tmp6 = tmpz[2].im + (unsigned)tmpz[3].im;
        tmp3 = tmpz[0].re - (unsigned)tmpz[1].re;
        tmp8 = tmpz[2].im - (unsigned)tmpz[3].im;
        tmp4 = tmpz[0].im - (unsigned)tmpz[1].im;
        tmp7 = tmpz[2].re - (unsigned)tmpz[3].re;

        tmpz[0].re = tmp1 + tmp5;
        tmpz[2].re = tmp1 - tmp5;
        tmpz[0].im = tmp2 + tmp6;
        tmpz[2].im = tmp2 - tmp6;
        tmpz[1].re = tmp3 + tmp8;
        tmpz[3].re = tmp3 - tmp8;
        tmpz[1].im = tmp4 - tmp7;
        tmpz[3].im = tmp4 + tmp7;
    }

    if (fft_size < 8)
        return;

    num_transforms = (num_transforms >> 1) | 1;

    for (n=0; n<num_transforms; n++){
        offset = ff_fft_offsets_lut[n] << 3;
        tmpz = z + offset;

        tmp1 = tmpz[4].re + (unsigned)tmpz[5].re;
        tmp3 = tmpz[6].re + (unsigned)tmpz[7].re;
        tmp2 = tmpz[4].im + (unsigned)tmpz[5].im;
        tmp4 = tmpz[6].im + (unsigned)tmpz[7].im;
        tmp5 = tmp1 + tmp3;
        tmp7 = tmp1 - tmp3;
        tmp6 = tmp2 + tmp4;
        tmp8 = tmp2 - tmp4;

        tmp1 = tmpz[4].re - (unsigned)tmpz[5].re;
        tmp2 = tmpz[4].im - (unsigned)tmpz[5].im;
        tmp3 = tmpz[6].re - (unsigned)tmpz[7].re;
        tmp4 = tmpz[6].im - (unsigned)tmpz[7].im;

        tmpz[4].re = tmpz[0].re - tmp5;
        tmpz[0].re = tmpz[0].re + tmp5;
        tmpz[4].im = tmpz[0].im - tmp6;
        tmpz[0].im = tmpz[0].im + tmp6;
        tmpz[6].re = tmpz[2].re - tmp8;
        tmpz[2].re = tmpz[2].re + tmp8;
        tmpz[6].im = tmpz[2].im + tmp7;
        tmpz[2].im = tmpz[2].im - tmp7;

        accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp1 + tmp2);
        tmp5 = (int32_t)((accu + 0x40000000) >> 31);
        accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp3 - tmp4);
        tmp7 = (int32_t)((accu + 0x40000000) >> 31);
        accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp2 - tmp1);
        tmp6 = (int32_t)((accu + 0x40000000) >> 31);
        accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp3 + tmp4);
        tmp8 = (int32_t)((accu + 0x40000000) >> 31);
        tmp1 = tmp5 + tmp7;
        tmp3 = tmp5 - tmp7;
        tmp2 = tmp6 + tmp8;
        tmp4 = tmp6 - tmp8;

        tmpz[5].re = tmpz[1].re - tmp1;
        tmpz[1].re = tmpz[1].re + tmp1;
        tmpz[5].im = tmpz[1].im - tmp2;
        tmpz[1].im = tmpz[1].im + tmp2;
        tmpz[7].re = tmpz[3].re - tmp4;
        tmpz[3].re = tmpz[3].re + tmp4;
        tmpz[7].im = tmpz[3].im + tmp3;
        tmpz[3].im = tmpz[3].im - tmp3;
    }

    step = 1 << ((MAX_LOG2_NFFT-4) - 4);
    n4 = 4;

    for (nbits=4; nbits<=s->nbits; nbits++){
        n2  = 2*n4;
        n34 = 3*n4;
        num_transforms = (num_transforms >> 1) | 1;

        for (n=0; n<num_transforms; n++){
            const FFTSample *w_re_ptr = ff_w_tab_sr + step;
            const FFTSample *w_im_ptr = ff_w_tab_sr + MAX_FFT_SIZE/(4*16) - step;
            offset = ff_fft_offsets_lut[n] << nbits;
            tmpz = z + offset;

            tmp5 = tmpz[ n2].re + (unsigned)tmpz[n34].re;
            tmp1 = tmpz[ n2].re - (unsigned)tmpz[n34].re;
            tmp6 = tmpz[ n2].im + (unsigned)tmpz[n34].im;
            tmp2 = tmpz[ n2].im - (unsigned)tmpz[n34].im;

            tmpz[ n2].re = tmpz[ 0].re - tmp5;
            tmpz[  0].re = tmpz[ 0].re + tmp5;
            tmpz[ n2].im = tmpz[ 0].im - tmp6;
            tmpz[  0].im = tmpz[ 0].im + tmp6;
            tmpz[n34].re = tmpz[n4].re - tmp2;
            tmpz[ n4].re = tmpz[n4].re + tmp2;
            tmpz[n34].im = tmpz[n4].im + tmp1;
            tmpz[ n4].im = tmpz[n4].im - tmp1;

            for (i=1; i<n4; i++){
                FFTSample w_re = w_re_ptr[0];
                FFTSample w_im = w_im_ptr[0];
                accu  = (int64_t)w_re*tmpz[ n2+i].re;
                accu += (int64_t)w_im*tmpz[ n2+i].im;
                tmp1 = (int32_t)((accu + 0x40000000) >> 31);
                accu  = (int64_t)w_re*tmpz[ n2+i].im;
                accu -= (int64_t)w_im*tmpz[ n2+i].re;
                tmp2 = (int32_t)((accu + 0x40000000) >> 31);
                accu  = (int64_t)w_re*tmpz[n34+i].re;
                accu -= (int64_t)w_im*tmpz[n34+i].im;
                tmp3 = (int32_t)((accu + 0x40000000) >> 31);
                accu  = (int64_t)w_re*tmpz[n34+i].im;
                accu += (int64_t)w_im*tmpz[n34+i].re;
                tmp4 = (int32_t)((accu + 0x40000000) >> 31);

                tmp5 = tmp1 + tmp3;
                tmp1 = tmp1 - tmp3;
                tmp6 = tmp2 + tmp4;
                tmp2 = tmp2 - tmp4;

                tmpz[ n2+i].re = tmpz[   i].re - tmp5;
                tmpz[    i].re = tmpz[   i].re + tmp5;
                tmpz[ n2+i].im = tmpz[   i].im - tmp6;
                tmpz[    i].im = tmpz[   i].im + tmp6;
                tmpz[n34+i].re = tmpz[n4+i].re - tmp2;
                tmpz[ n4+i].re = tmpz[n4+i].re + tmp2;
                tmpz[n34+i].im = tmpz[n4+i].im + tmp1;
                tmpz[ n4+i].im = tmpz[n4+i].im - tmp1;

                w_re_ptr += step;
                w_im_ptr -= step;
            }
        }
        step >>= 1;
        n4   <<= 1;
    }
}

#else /* FFT_FIXED_32 */

#define BUTTERFLIES(a0,a1,a2,a3) {\
    BF(t3, t5, t5, t1);\
    BF(a2.re, a0.re, a0.re, t5);\
    BF(a3.im, a1.im, a1.im, t3);\
    BF(t4, t6, t2, t6);\
    BF(a3.re, a1.re, a1.re, t4);\
    BF(a2.im, a0.im, a0.im, t6);\
}

// force loading all the inputs before storing any.
// this is slightly slower for small data, but avoids store->load aliasing
// for addresses separated by large powers of 2.
#define BUTTERFLIES_BIG(a0,a1,a2,a3) {\
    FFTSample r0=a0.re, i0=a0.im, r1=a1.re, i1=a1.im;\
    BF(t3, t5, t5, t1);\
    BF(a2.re, a0.re, r0, t5);\
    BF(a3.im, a1.im, i1, t3);\
    BF(t4, t6, t2, t6);\
    BF(a3.re, a1.re, r1, t4);\
    BF(a2.im, a0.im, i0, t6);\
}

#define TRANSFORM(a0,a1,a2,a3,wre,wim) {\
    CMUL(t1, t2, a2.re, a2.im, wre, -wim);\
    CMUL(t5, t6, a3.re, a3.im, wre,  wim);\
    BUTTERFLIES(a0,a1,a2,a3)\
}

#define TRANSFORM_ZERO(a0,a1,a2,a3) {\
    t1 = a2.re;\
    t2 = a2.im;\
    t5 = a3.re;\
    t6 = a3.im;\
    BUTTERFLIES(a0,a1,a2,a3)\
}

/* z[0...8n-1], w[1...2n-1] */
#define PASS(name)\
static void name(FFTComplex *z, const FFTSample *wre, unsigned int n)\
{\
    FFTDouble t1, t2, t3, t4, t5, t6;\
    int o1 = 2*n;\
    int o2 = 4*n;\
    int o3 = 6*n;\
    const FFTSample *wim = wre+o1;\
    n--;\
\
    TRANSFORM_ZERO(z[0],z[o1],z[o2],z[o3]);\
    TRANSFORM(z[1],z[o1+1],z[o2+1],z[o3+1],wre[1],wim[-1]);\
    do {\
        z += 2;\
        wre += 2;\
        wim -= 2;\
        TRANSFORM(z[0],z[o1],z[o2],z[o3],wre[0],wim[0]);\
        TRANSFORM(z[1],z[o1+1],z[o2+1],z[o3+1],wre[1],wim[-1]);\
    } while(--n);\
}

PASS(pass)
#if !CONFIG_SMALL
#undef BUTTERFLIES
#define BUTTERFLIES BUTTERFLIES_BIG
PASS(pass_big)
#endif

#define DECL_FFT(n,n2,n4)\
static void fft##n(FFTComplex *z)\
{\
    fft##n2(z);\
    fft##n4(z+n4*2);\
    fft##n4(z+n4*3);\
    pass(z,FFT_NAME(ff_cos_##n),n4/2);\
}

static void fft4(FFTComplex *z)
{
    FFTDouble t1, t2, t3, t4, t5, t6, t7, t8;

    BF(t3, t1, z[0].re, z[1].re);
    BF(t8, t6, z[3].re, z[2].re);
    BF(z[2].re, z[0].re, t1, t6);
    BF(t4, t2, z[0].im, z[1].im);
    BF(t7, t5, z[2].im, z[3].im);
    BF(z[3].im, z[1].im, t4, t8);
    BF(z[3].re, z[1].re, t3, t7);
    BF(z[2].im, z[0].im, t2, t5);
}

static void fft8(FFTComplex *z)
{
    FFTDouble t1, t2, t3, t4, t5, t6;

    fft4(z);

    BF(t1, z[5].re, z[4].re, -z[5].re);
    BF(t2, z[5].im, z[4].im, -z[5].im);
    BF(t5, z[7].re, z[6].re, -z[7].re);
    BF(t6, z[7].im, z[6].im, -z[7].im);

    BUTTERFLIES(z[0],z[2],z[4],z[6]);
    TRANSFORM(z[1],z[3],z[5],z[7],sqrthalf,sqrthalf);
}

#if !CONFIG_SMALL
static void fft16(FFTComplex *z)
{
    FFTDouble t1, t2, t3, t4, t5, t6;
    FFTSample cos_16_1 = FFT_NAME(ff_cos_16)[1];
    FFTSample cos_16_3 = FFT_NAME(ff_cos_16)[3];

    fft8(z);
    fft4(z+8);
    fft4(z+12);

    TRANSFORM_ZERO(z[0],z[4],z[8],z[12]);
    TRANSFORM(z[2],z[6],z[10],z[14],sqrthalf,sqrthalf);
    TRANSFORM(z[1],z[5],z[9],z[13],cos_16_1,cos_16_3);
    TRANSFORM(z[3],z[7],z[11],z[15],cos_16_3,cos_16_1);
}
#else
DECL_FFT(16,8,4)
#endif
DECL_FFT(32,16,8)
DECL_FFT(64,32,16)
DECL_FFT(128,64,32)
DECL_FFT(256,128,64)
DECL_FFT(512,256,128)
#if !CONFIG_SMALL
#define pass pass_big
#endif
DECL_FFT(1024,512,256)
DECL_FFT(2048,1024,512)
DECL_FFT(4096,2048,1024)
DECL_FFT(8192,4096,2048)
DECL_FFT(16384,8192,4096)
DECL_FFT(32768,16384,8192)
DECL_FFT(65536,32768,16384)
DECL_FFT(131072,65536,32768)

static void (* const fft_dispatch[])(FFTComplex*) = {
    fft4, fft8, fft16, fft32, fft64, fft128, fft256, fft512, fft1024,
    fft2048, fft4096, fft8192, fft16384, fft32768, fft65536, fft131072
};

static void fft_calc_c(FFTContext *s, FFTComplex *z)
{
    fft_dispatch[s->nbits-2](z);
}
#endif /* FFT_FIXED_32 */


Generated by: GCOVR (Version 4.2)

Line	Branch	Exec	Source
1			/*
2			* FFT/IFFT transforms
3			* Copyright (c) 2008 Loren Merritt
4			* Copyright (c) 2002 Fabrice Bellard
5			* Partly based on libdjbfft by D. J. Bernstein
6			*
7			* This file is part of FFmpeg.
8			*
9			* FFmpeg is free software; you can redistribute it and/or
10			* modify it under the terms of the GNU Lesser General Public
11			* License as published by the Free Software Foundation; either
12			* version 2.1 of the License, or (at your option) any later version.
13			*
14			* FFmpeg is distributed in the hope that it will be useful,
15			* but WITHOUT ANY WARRANTY; without even the implied warranty of
16			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17			* Lesser General Public License for more details.
18			*
19			* You should have received a copy of the GNU Lesser General Public
20			* License along with FFmpeg; if not, write to the Free Software
21			* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22			*/
23
24			/**
25			* @file
26			* FFT/IFFT transforms.
27			*/
28
29			#include <stdlib.h>
30			#include <string.h>
31			#include "libavutil/mathematics.h"
32			#include "libavutil/thread.h"
33			#include "fft.h"
34			#include "fft-internal.h"
35
36			#if FFT_FIXED_32
37			#include "fft_table.h"
38			#else /* FFT_FIXED_32 */
39
40			/* cos(2pix/n) for 0<=x<=n/4, followed by its reverse */
41			#if !CONFIG_HARDCODED_TABLES
42			COSTABLE(16);
43			COSTABLE(32);
44			COSTABLE(64);
45			COSTABLE(128);
46			COSTABLE(256);
47			COSTABLE(512);
48			COSTABLE(1024);
49			COSTABLE(2048);
50			COSTABLE(4096);
51			COSTABLE(8192);
52			COSTABLE(16384);
53			COSTABLE(32768);
54			COSTABLE(65536);
55			COSTABLE(131072);
56
57		2426	static av_cold void init_ff_cos_tabs(int index)
58			{
59			int i;
60		2426	int m = 1<<index;
61		2426	double freq = 2*M_PI/m;
62		2426	FFTSample *tab = FFT_NAME(ff_cos_tabs)[index];
63	✓✓	180452	for(i=0; i<=m/4; i++)
64		178026	tab[i] = FIX15(cos(i*freq));
65	✓✓	175600	for(i=1; i<m/4; i++)
66		173174	tab[m/2-i] = tab[i];
67		2426	}
68
69			typedef struct CosTabsInitOnce {
70			void (*func)(void);
71			AVOnce control;
72			} CosTabsInitOnce;
73
74			#define INIT_FF_COS_TABS_FUNC(index, size) \
75			static av_cold void init_ff_cos_tabs_ ## size (void)\
76			{ \
77			init_ff_cos_tabs(index); \
78			}
79
80		478	INIT_FF_COS_TABS_FUNC(4, 16)
81		461	INIT_FF_COS_TABS_FUNC(5, 32)
82		387	INIT_FF_COS_TABS_FUNC(6, 64)
83		363	INIT_FF_COS_TABS_FUNC(7, 128)
84		310	INIT_FF_COS_TABS_FUNC(8, 256)
85		286	INIT_FF_COS_TABS_FUNC(9, 512)
86		68	INIT_FF_COS_TABS_FUNC(10, 1024)
87		37	INIT_FF_COS_TABS_FUNC(11, 2048)
88		24	INIT_FF_COS_TABS_FUNC(12, 4096)
89		7	INIT_FF_COS_TABS_FUNC(13, 8192)
90		5	INIT_FF_COS_TABS_FUNC(14, 16384)
91			INIT_FF_COS_TABS_FUNC(15, 32768)
92			INIT_FF_COS_TABS_FUNC(16, 65536)
93			INIT_FF_COS_TABS_FUNC(17, 131072)
94
95			static CosTabsInitOnce cos_tabs_init_once[] = {
96			{ NULL },
97			{ NULL },
98			{ NULL },
99			{ NULL },
100			{ init_ff_cos_tabs_16, AV_ONCE_INIT },
101			{ init_ff_cos_tabs_32, AV_ONCE_INIT },
102			{ init_ff_cos_tabs_64, AV_ONCE_INIT },
103			{ init_ff_cos_tabs_128, AV_ONCE_INIT },
104			{ init_ff_cos_tabs_256, AV_ONCE_INIT },
105			{ init_ff_cos_tabs_512, AV_ONCE_INIT },
106			{ init_ff_cos_tabs_1024, AV_ONCE_INIT },
107			{ init_ff_cos_tabs_2048, AV_ONCE_INIT },
108			{ init_ff_cos_tabs_4096, AV_ONCE_INIT },
109			{ init_ff_cos_tabs_8192, AV_ONCE_INIT },
110			{ init_ff_cos_tabs_16384, AV_ONCE_INIT },
111			{ init_ff_cos_tabs_32768, AV_ONCE_INIT },
112			{ init_ff_cos_tabs_65536, AV_ONCE_INIT },
113			{ init_ff_cos_tabs_131072, AV_ONCE_INIT },
114			};
115
116			#endif
117			COSTABLE_CONST FFTSample * const FFT_NAME(ff_cos_tabs)[] = {
118			NULL, NULL, NULL, NULL,
119			FFT_NAME(ff_cos_16),
120			FFT_NAME(ff_cos_32),
121			FFT_NAME(ff_cos_64),
122			FFT_NAME(ff_cos_128),
123			FFT_NAME(ff_cos_256),
124			FFT_NAME(ff_cos_512),
125			FFT_NAME(ff_cos_1024),
126			FFT_NAME(ff_cos_2048),
127			FFT_NAME(ff_cos_4096),
128			FFT_NAME(ff_cos_8192),
129			FFT_NAME(ff_cos_16384),
130			FFT_NAME(ff_cos_32768),
131			FFT_NAME(ff_cos_65536),
132			FFT_NAME(ff_cos_131072),
133			};
134
135			#endif /* FFT_FIXED_32 */
136
137			static void fft_permute_c(FFTContext s, FFTComplex z);
138			static void fft_calc_c(FFTContext s, FFTComplex z);
139
140		5126024	static int split_radix_permutation(int i, int n, int inverse)
141			{
142			int m;
143	✓✓	5126024	if(n <= 2) return i&1;
144		4369464	m = n >> 1;
145	✓✓	4369464	if(!(i&m)) return split_radix_permutation(i, m, inverse)*2;
146		2184732	m >>= 1;
147	✓✓	2184732	if(inverse == !(i&m)) return split_radix_permutation(i, m, inverse)*4 + 1;
148		1092366	else return split_radix_permutation(i, m, inverse)*4 - 1;
149			}
150
151		10389	av_cold void ff_init_ff_cos_tabs(int index)
152			{
153			#if (!CONFIG_HARDCODED_TABLES) && (!FFT_FIXED_32)
154		10389	ff_thread_once(&cos_tabs_init_once[index].control, cos_tabs_init_once[index].func);
155			#endif
156		10389	}
157
158			static const int avx_tab[] = {
159			0, 4, 1, 5, 8, 12, 9, 13, 2, 6, 3, 7, 10, 14, 11, 15
160			};
161
162		14530	static int is_second_half_of_fft32(int i, int n)
163			{
164	✓✓	14530	if (n <= 32)
165		4090	return i >= 16;
166	✓✓	10440	else if (i < n/2)
167		5220	return is_second_half_of_fft32(i, n/2);
168	✓✓	5220	else if (i < 3*n/4)
169		2610	return is_second_half_of_fft32(i - n/2, n/4);
170			else
171		2610	return is_second_half_of_fft32(i - 3*n/4, n/4);
172			}
173
174		303	static av_cold void fft_perm_avx(FFTContext *s)
175			{
176			int i;
177		303	int n = 1 << s->nbits;
178
179	✓✓	4393	for (i = 0; i < n; i += 16) {
180			int k;
181	✓✓	4090	if (is_second_half_of_fft32(i, n)) {
182	✓✓	23783	for (k = 0; k < 16; k++)
183		44768	s->revtab[-split_radix_permutation(i + k, n, s->inverse) & (n - 1)] =
184		22384	i + avx_tab[k];
185
186			} else {
187	✓✓	45747	for (k = 0; k < 16; k++) {
188		43056	int j = i + k;
189		43056	j = (j & ~7) \| ((j >> 1) & 3) \| ((j << 2) & 4);
190		43056	s->revtab[-split_radix_permutation(i + k, n, s->inverse) & (n - 1)] = j;
191			}
192			}
193			}
194		303	}
195
196		3566	av_cold int ff_fft_init(FFTContext *s, int nbits, int inverse)
197			{
198			int i, j, n;
199
200		3566	s->revtab = NULL;
201		3566	s->revtab32 = NULL;
202
203	✓✗✗✓	3566	if (nbits < 2 \|\| nbits > 17)
204			goto fail;
205		3566	s->nbits = nbits;
206		3566	n = 1 << nbits;
207
208	✓✗	3566	if (nbits <= 16) {
209		3566	s->revtab = av_malloc(n * sizeof(uint16_t));
210	✗✓	3566	if (!s->revtab)
211			goto fail;
212			} else {
213			s->revtab32 = av_malloc(n * sizeof(uint32_t));
214			if (!s->revtab32)
215			goto fail;
216			}
217		3566	s->tmp_buf = av_malloc(n * sizeof(FFTComplex));
218	✗✓	3566	if (!s->tmp_buf)
219			goto fail;
220		3566	s->inverse = inverse;
221		3566	s->fft_permutation = FF_FFT_PERM_DEFAULT;
222
223		3566	s->fft_permute = fft_permute_c;
224		3566	s->fft_calc = fft_calc_c;
225			#if CONFIG_MDCT
226		3566	s->imdct_calc = ff_imdct_calc_c;
227		3566	s->imdct_half = ff_imdct_half_c;
228		3566	s->mdct_calc = ff_mdct_calc_c;
229			#endif
230
231			#if FFT_FIXED_32
232		188	ff_fft_lut_init();
233			#else /* FFT_FIXED_32 */
234			#if FFT_FLOAT
235			if (ARCH_AARCH64) ff_fft_init_aarch64(s);
236			if (ARCH_ARM) ff_fft_init_arm(s);
237			if (ARCH_PPC) ff_fft_init_ppc(s);
238		3378	if (ARCH_X86) ff_fft_init_x86(s);
239			if (HAVE_MIPSFPU) ff_fft_init_mips(s);
240			#endif
241	✓✓	13588	for(j=4; j<=nbits; j++) {
242		10210	ff_init_ff_cos_tabs(j);
243			}
244			#endif /* FFT_FIXED_32 */
245
246
247	✓✓	3378	if (ARCH_X86 && FFT_FLOAT && s->fft_permutation == FF_FFT_PERM_AVX) {
248		303	fft_perm_avx(s);
249			} else {
250			#define PROCESS_FFT_PERM_SWAP_LSBS(num) do {\
251			for(i = 0; i < n; i++) {\
252			int k;\
253			j = i;\
254			j = (j & ~3) \| ((j >> 1) & 1) \| ((j << 1) & 2);\
255			k = -split_radix_permutation(i, n, s->inverse) & (n - 1);\
256			s->revtab##num[k] = j;\
257			} \
258			} while(0);
259
260			#define PROCESS_FFT_PERM_DEFAULT(num) do {\
261			for(i = 0; i < n; i++) {\
262			int k;\
263			j = i;\
264			k = -split_radix_permutation(i, n, s->inverse) & (n - 1);\
265			s->revtab##num[k] = j;\
266			} \
267			} while(0);
268
269			#define SPLIT_RADIX_PERMUTATION(num) do { \
270			if (s->fft_permutation == FF_FFT_PERM_SWAP_LSBS) {\
271			PROCESS_FFT_PERM_SWAP_LSBS(num) \
272			} else {\
273			PROCESS_FFT_PERM_DEFAULT(num) \
274			}\
275			} while(0);
276
277	✓✗	3263	if (s->revtab)
278	✓✓✓✓ ✓✓	694383	SPLIT_RADIX_PERMUTATION()
279	✗✓	3263	if (s->revtab32)
280			SPLIT_RADIX_PERMUTATION(32)
281
282			#undef PROCESS_FFT_PERM_DEFAULT
283			#undef PROCESS_FFT_PERM_SWAP_LSBS
284			#undef SPLIT_RADIX_PERMUTATION
285			}
286
287		3566	return 0;
288			fail:
289			av_freep(&s->revtab);
290			av_freep(&s->revtab32);
291			av_freep(&s->tmp_buf);
292			return -1;
293			}
294
295		48062	static void fft_permute_c(FFTContext s, FFTComplex z)
296			{
297			int j, np;
298		48062	const uint16_t *revtab = s->revtab;
299		48062	const uint32_t *revtab32 = s->revtab32;
300		48062	np = 1 << s->nbits;
301			/* TODO: handle split-radix permute in a more optimal way, probably in-place */
302	✓✗	48062	if (revtab) {
303	✓✓	12905982	for(j=0;j<np;j++) s->tmp_buf[revtab[j]] = z[j];
304			} else
305			for(j=0;j<np;j++) s->tmp_buf[revtab32[j]] = z[j];
306
307		48062	memcpy(z, s->tmp_buf, np * sizeof(FFTComplex));
308		48062	}
309
310		3660	av_cold void ff_fft_end(FFTContext *s)
311			{
312		3660	av_freep(&s->revtab);
313		3660	av_freep(&s->revtab32);
314		3660	av_freep(&s->tmp_buf);
315		3660	}
316
317			#if FFT_FIXED_32
318
319		770822	static void fft_calc_c(FFTContext s, FFTComplex z) {
320
321			int nbits, i, n, num_transforms, offset, step;
322			int n4, n2, n34;
323			unsigned tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7, tmp8;
324			FFTComplex *tmpz;
325		770822	const int fft_size = (1 << s->nbits);
326			int64_t accu;
327
328		770822	num_transforms = (0x2aab >> (16 - s->nbits)) \| 1;
329
330	✓✓	6613534	for (n=0; n<num_transforms; n++){
331		5842712	offset = ff_fft_offsets_lut[n] << 2;
332		5842712	tmpz = z + offset;
333
334		5842712	tmp1 = tmpz[0].re + (unsigned)tmpz[1].re;
335		5842712	tmp5 = tmpz[2].re + (unsigned)tmpz[3].re;
336		5842712	tmp2 = tmpz[0].im + (unsigned)tmpz[1].im;
337		5842712	tmp6 = tmpz[2].im + (unsigned)tmpz[3].im;
338		5842712	tmp3 = tmpz[0].re - (unsigned)tmpz[1].re;
339		5842712	tmp8 = tmpz[2].im - (unsigned)tmpz[3].im;
340		5842712	tmp4 = tmpz[0].im - (unsigned)tmpz[1].im;
341		5842712	tmp7 = tmpz[2].re - (unsigned)tmpz[3].re;
342
343		5842712	tmpz[0].re = tmp1 + tmp5;
344		5842712	tmpz[2].re = tmp1 - tmp5;
345		5842712	tmpz[0].im = tmp2 + tmp6;
346		5842712	tmpz[2].im = tmp2 - tmp6;
347		5842712	tmpz[1].re = tmp3 + tmp8;
348		5842712	tmpz[3].re = tmp3 - tmp8;
349		5842712	tmpz[1].im = tmp4 - tmp7;
350		5842712	tmpz[3].im = tmp4 + tmp7;
351			}
352
353	✓✓	770822	if (fft_size < 8)
354		1	return;
355
356		770821	num_transforms = (num_transforms >> 1) \| 1;
357
358	✓✓	4059972	for (n=0; n<num_transforms; n++){
359		3289151	offset = ff_fft_offsets_lut[n] << 3;
360		3289151	tmpz = z + offset;
361
362		3289151	tmp1 = tmpz[4].re + (unsigned)tmpz[5].re;
363		3289151	tmp3 = tmpz[6].re + (unsigned)tmpz[7].re;
364		3289151	tmp2 = tmpz[4].im + (unsigned)tmpz[5].im;
365		3289151	tmp4 = tmpz[6].im + (unsigned)tmpz[7].im;
366		3289151	tmp5 = tmp1 + tmp3;
367		3289151	tmp7 = tmp1 - tmp3;
368		3289151	tmp6 = tmp2 + tmp4;
369		3289151	tmp8 = tmp2 - tmp4;
370
371		3289151	tmp1 = tmpz[4].re - (unsigned)tmpz[5].re;
372		3289151	tmp2 = tmpz[4].im - (unsigned)tmpz[5].im;
373		3289151	tmp3 = tmpz[6].re - (unsigned)tmpz[7].re;
374		3289151	tmp4 = tmpz[6].im - (unsigned)tmpz[7].im;
375
376		3289151	tmpz[4].re = tmpz[0].re - tmp5;
377		3289151	tmpz[0].re = tmpz[0].re + tmp5;
378		3289151	tmpz[4].im = tmpz[0].im - tmp6;
379		3289151	tmpz[0].im = tmpz[0].im + tmp6;
380		3289151	tmpz[6].re = tmpz[2].re - tmp8;
381		3289151	tmpz[2].re = tmpz[2].re + tmp8;
382		3289151	tmpz[6].im = tmpz[2].im + tmp7;
383		3289151	tmpz[2].im = tmpz[2].im - tmp7;
384
385		3289151	accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp1 + tmp2);
386		3289151	tmp5 = (int32_t)((accu + 0x40000000) >> 31);
387		3289151	accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp3 - tmp4);
388		3289151	tmp7 = (int32_t)((accu + 0x40000000) >> 31);
389		3289151	accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp2 - tmp1);
390		3289151	tmp6 = (int32_t)((accu + 0x40000000) >> 31);
391		3289151	accu = (int64_t)Q31(M_SQRT1_2)*(int)(tmp3 + tmp4);
392		3289151	tmp8 = (int32_t)((accu + 0x40000000) >> 31);
393		3289151	tmp1 = tmp5 + tmp7;
394		3289151	tmp3 = tmp5 - tmp7;
395		3289151	tmp2 = tmp6 + tmp8;
396		3289151	tmp4 = tmp6 - tmp8;
397
398		3289151	tmpz[5].re = tmpz[1].re - tmp1;
399		3289151	tmpz[1].re = tmpz[1].re + tmp1;
400		3289151	tmpz[5].im = tmpz[1].im - tmp2;
401		3289151	tmpz[1].im = tmpz[1].im + tmp2;
402		3289151	tmpz[7].re = tmpz[3].re - tmp4;
403		3289151	tmpz[3].re = tmpz[3].re + tmp4;
404		3289151	tmpz[7].im = tmpz[3].im + tmp3;
405		3289151	tmpz[3].im = tmpz[3].im - tmp3;
406			}
407
408		770821	step = 1 << ((MAX_LOG2_NFFT-4) - 4);
409		770821	n4 = 4;
410
411	✓✓	2441198	for (nbits=4; nbits<=s->nbits; nbits++){
412		1670377	n2 = 2*n4;
413		1670377	n34 = 3*n4;
414		1670377	num_transforms = (num_transforms >> 1) \| 1;
415
416	✓✓	4206322	for (n=0; n<num_transforms; n++){
417		2535945	const FFTSample *w_re_ptr = ff_w_tab_sr + step;
418		2535945	const FFTSample w_im_ptr = ff_w_tab_sr + MAX_FFT_SIZE/(416) - step;
419		2535945	offset = ff_fft_offsets_lut[n] << nbits;
420		2535945	tmpz = z + offset;
421
422		2535945	tmp5 = tmpz[ n2].re + (unsigned)tmpz[n34].re;
423		2535945	tmp1 = tmpz[ n2].re - (unsigned)tmpz[n34].re;
424		2535945	tmp6 = tmpz[ n2].im + (unsigned)tmpz[n34].im;
425		2535945	tmp2 = tmpz[ n2].im - (unsigned)tmpz[n34].im;
426
427		2535945	tmpz[ n2].re = tmpz[ 0].re - tmp5;
428		2535945	tmpz[ 0].re = tmpz[ 0].re + tmp5;
429		2535945	tmpz[ n2].im = tmpz[ 0].im - tmp6;
430		2535945	tmpz[ 0].im = tmpz[ 0].im + tmp6;
431		2535945	tmpz[n34].re = tmpz[n4].re - tmp2;
432		2535945	tmpz[ n4].re = tmpz[n4].re + tmp2;
433		2535945	tmpz[n34].im = tmpz[n4].im + tmp1;
434		2535945	tmpz[ n4].im = tmpz[n4].im - tmp1;
435
436	✓✓	21618072	for (i=1; i<n4; i++){
437		19082127	FFTSample w_re = w_re_ptr[0];
438		19082127	FFTSample w_im = w_im_ptr[0];
439		19082127	accu = (int64_t)w_re*tmpz[ n2+i].re;
440		19082127	accu += (int64_t)w_im*tmpz[ n2+i].im;
441		19082127	tmp1 = (int32_t)((accu + 0x40000000) >> 31);
442		19082127	accu = (int64_t)w_re*tmpz[ n2+i].im;
443		19082127	accu -= (int64_t)w_im*tmpz[ n2+i].re;
444		19082127	tmp2 = (int32_t)((accu + 0x40000000) >> 31);
445		19082127	accu = (int64_t)w_re*tmpz[n34+i].re;
446		19082127	accu -= (int64_t)w_im*tmpz[n34+i].im;
447		19082127	tmp3 = (int32_t)((accu + 0x40000000) >> 31);
448		19082127	accu = (int64_t)w_re*tmpz[n34+i].im;
449		19082127	accu += (int64_t)w_im*tmpz[n34+i].re;
450		19082127	tmp4 = (int32_t)((accu + 0x40000000) >> 31);
451
452		19082127	tmp5 = tmp1 + tmp3;
453		19082127	tmp1 = tmp1 - tmp3;
454		19082127	tmp6 = tmp2 + tmp4;
455		19082127	tmp2 = tmp2 - tmp4;
456
457		19082127	tmpz[ n2+i].re = tmpz[ i].re - tmp5;
458		19082127	tmpz[ i].re = tmpz[ i].re + tmp5;
459		19082127	tmpz[ n2+i].im = tmpz[ i].im - tmp6;
460		19082127	tmpz[ i].im = tmpz[ i].im + tmp6;
461		19082127	tmpz[n34+i].re = tmpz[n4+i].re - tmp2;
462		19082127	tmpz[ n4+i].re = tmpz[n4+i].re + tmp2;
463		19082127	tmpz[n34+i].im = tmpz[n4+i].im + tmp1;
464		19082127	tmpz[ n4+i].im = tmpz[n4+i].im - tmp1;
465
466		19082127	w_re_ptr += step;
467		19082127	w_im_ptr -= step;
468			}
469			}
470		1670377	step >>= 1;
471		1670377	n4 <<= 1;
472			}
473			}
474
475			#else /* FFT_FIXED_32 */
476
477			#define BUTTERFLIES(a0,a1,a2,a3) {\
478			BF(t3, t5, t5, t1);\
479			BF(a2.re, a0.re, a0.re, t5);\
480			BF(a3.im, a1.im, a1.im, t3);\
481			BF(t4, t6, t2, t6);\
482			BF(a3.re, a1.re, a1.re, t4);\
483			BF(a2.im, a0.im, a0.im, t6);\
484			}
485
486			// force loading all the inputs before storing any.
487			// this is slightly slower for small data, but avoids store->load aliasing
488			// for addresses separated by large powers of 2.
489			#define BUTTERFLIES_BIG(a0,a1,a2,a3) {\
490			FFTSample r0=a0.re, i0=a0.im, r1=a1.re, i1=a1.im;\
491			BF(t3, t5, t5, t1);\
492			BF(a2.re, a0.re, r0, t5);\
493			BF(a3.im, a1.im, i1, t3);\
494			BF(t4, t6, t2, t6);\
495			BF(a3.re, a1.re, r1, t4);\
496			BF(a2.im, a0.im, i0, t6);\
497			}
498
499			#define TRANSFORM(a0,a1,a2,a3,wre,wim) {\
500			CMUL(t1, t2, a2.re, a2.im, wre, -wim);\
501			CMUL(t5, t6, a3.re, a3.im, wre, wim);\
502			BUTTERFLIES(a0,a1,a2,a3)\
503			}
504
505			#define TRANSFORM_ZERO(a0,a1,a2,a3) {\
506			t1 = a2.re;\
507			t2 = a2.im;\
508			t5 = a3.re;\
509			t6 = a3.im;\
510			BUTTERFLIES(a0,a1,a2,a3)\
511			}
512
513			/* z[0...8n-1], w[1...2n-1] */
514			#define PASS(name)\
515			static void name(FFTComplex z, const FFTSample wre, unsigned int n)\
516			{\
517			FFTDouble t1, t2, t3, t4, t5, t6;\
518			int o1 = 2*n;\
519			int o2 = 4*n;\
520			int o3 = 6*n;\
521			const FFTSample *wim = wre+o1;\
522			n--;\
523			\
524			TRANSFORM_ZERO(z[0],z[o1],z[o2],z[o3]);\
525			TRANSFORM(z[1],z[o1+1],z[o2+1],z[o3+1],wre[1],wim[-1]);\
526			do {\
527			z += 2;\
528			wre += 2;\
529			wim -= 2;\
530			TRANSFORM(z[0],z[o1],z[o2],z[o3],wre[0],wim[0]);\
531			TRANSFORM(z[1],z[o1+1],z[o2+1],z[o3+1],wre[1],wim[-1]);\
532			} while(--n);\
533			}
534
535	✓✓	25745265	PASS(pass)
536			#if !CONFIG_SMALL
537			#undef BUTTERFLIES
538			#define BUTTERFLIES BUTTERFLIES_BIG
539	✓✓	3063261	PASS(pass_big)
540			#endif
541
542			#define DECL_FFT(n,n2,n4)\
543			static void fft##n(FFTComplex *z)\
544			{\
545			fft##n2(z);\
546			fft##n4(z+n4*2);\
547			fft##n4(z+n4*3);\
548			pass(z,FFT_NAME(ff_cos_##n),n4/2);\
549			}
550
551		18920291	static void fft4(FFTComplex *z)
552			{
553			FFTDouble t1, t2, t3, t4, t5, t6, t7, t8;
554
555		18920291	BF(t3, t1, z[0].re, z[1].re);
556		18920291	BF(t8, t6, z[3].re, z[2].re);
557		18920291	BF(z[2].re, z[0].re, t1, t6);
558		18920291	BF(t4, t2, z[0].im, z[1].im);
559		18920291	BF(t7, t5, z[2].im, z[3].im);
560		18920291	BF(z[3].im, z[1].im, t4, t8);
561		18920291	BF(z[3].re, z[1].re, t3, t7);
562		18920291	BF(z[2].im, z[0].im, t2, t5);
563		18920291	}
564
565		9627643	static void fft8(FFTComplex *z)
566			{
567			FFTDouble t1, t2, t3, t4, t5, t6;
568
569		9627643	fft4(z);
570
571		9627643	BF(t1, z[5].re, z[4].re, -z[5].re);
572		9627643	BF(t2, z[5].im, z[4].im, -z[5].im);
573		9627643	BF(t5, z[7].re, z[6].re, -z[7].re);
574		9627643	BF(t6, z[7].im, z[6].im, -z[7].im);
575
576		9627643	BUTTERFLIES(z[0],z[2],z[4],z[6]);
577		9627643	TRANSFORM(z[1],z[3],z[5],z[7],sqrthalf,sqrthalf);
578		9627643	}
579
580			#if !CONFIG_SMALL
581		4134447	static void fft16(FFTComplex *z)
582			{
583			FFTDouble t1, t2, t3, t4, t5, t6;
584		4134447	FFTSample cos_16_1 = FFT_NAME(ff_cos_16)[1];
585		4134447	FFTSample cos_16_3 = FFT_NAME(ff_cos_16)[3];
586
587		4134447	fft8(z);
588		4134447	fft4(z+8);
589		4134447	fft4(z+12);
590
591		4134447	TRANSFORM_ZERO(z[0],z[4],z[8],z[12]);
592		4134447	TRANSFORM(z[2],z[6],z[10],z[14],sqrthalf,sqrthalf);
593		4134447	TRANSFORM(z[1],z[5],z[9],z[13],cos_16_1,cos_16_3);
594		4134447	TRANSFORM(z[3],z[7],z[11],z[15],cos_16_3,cos_16_1);
595		4134447	}
596			#else
597			DECL_FFT(16,8,4)
598			#endif
599		2592773	DECL_FFT(32,16,8)
600		631259	DECL_FFT(64,32,16)
601		324172	DECL_FFT(128,64,32)
602		114796	DECL_FFT(256,128,64)
603		81379	DECL_FFT(512,256,128)
604			#if !CONFIG_SMALL
605			#define pass pass_big
606			#endif
607		8553	DECL_FFT(1024,512,256)
608		2969	DECL_FFT(2048,1024,512)
609		1008	DECL_FFT(4096,2048,1024)
610		689	DECL_FFT(8192,4096,2048)
611			DECL_FFT(16384,8192,4096)
612			DECL_FFT(32768,16384,8192)
613			DECL_FFT(65536,32768,16384)
614			DECL_FFT(131072,65536,32768)
615
616			static void (* const fft_dispatch[])(FFTComplex*) = {
617			fft4, fft8, fft16, fft32, fft64, fft128, fft256, fft512, fft1024,
618			fft2048, fft4096, fft8192, fft16384, fft32768, fft65536, fft131072
619			};
620
621		3136201	static void fft_calc_c(FFTContext s, FFTComplex z)
622			{
623		3136201	fft_dispatch[s->nbits-2](z);
624		3136201	}
625			#endif /* FFT_FIXED_32 */