PeerStreamer

/*

 * FFT/MDCT transform with 3DNow! optimizations

 * Copyright (c) 2006 Zuxy MENG Jie, Loren Merritt

 * Based on fft_sse.c copyright (c) 2002 Fabrice Bellard.

 *

 * 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 "dsputil.h"

static const int p1m1[2] __attribute__((aligned(8))) =

    { 0, 1 << 31 };

static const int m1p1[2] __attribute__((aligned(8))) =

    { 1 << 31, 0 };

void ff_fft_calc_3dn(FFTContext *s, FFTComplex *z)

{

    int ln = s->nbits;

    long i, j;

    long nblocks, nloops;

    FFTComplex *p, *cptr;

    asm volatile(

        /* FEMMS is not a must here but recommended by AMD */

        "femms \n\t"

        "movq %0, %%mm7 \n\t"

        ::"m"(*(s->inverse ? m1p1 : p1m1))

    );

    i = 8 << ln;

    asm volatile(

        "1: \n\t"

        "sub $32, %0 \n\t"

        "movq    (%0,%1), %%mm0 \n\t"

        "movq  16(%0,%1), %%mm1 \n\t"

        "movq   8(%0,%1), %%mm2 \n\t"

        "movq  24(%0,%1), %%mm3 \n\t"

        "movq      %%mm0, %%mm4 \n\t"

        "movq      %%mm1, %%mm5 \n\t"

        "pfadd     %%mm2, %%mm0 \n\t"

        "pfadd     %%mm3, %%mm1 \n\t"

        "pfsub     %%mm2, %%mm4 \n\t"

        "pfsub     %%mm3, %%mm5 \n\t"

        "movq      %%mm0, %%mm2 \n\t"

        "punpckldq %%mm5, %%mm6 \n\t"

        "punpckhdq %%mm6, %%mm5 \n\t"

        "movq      %%mm4, %%mm3 \n\t"

        "pxor      %%mm7, %%mm5 \n\t"

        "pfadd     %%mm1, %%mm0 \n\t"

        "pfadd     %%mm5, %%mm4 \n\t"

        "pfsub     %%mm1, %%mm2 \n\t"

        "pfsub     %%mm5, %%mm3 \n\t"

        "movq      %%mm0,   (%0,%1) \n\t"

        "movq      %%mm4,  8(%0,%1) \n\t"

        "movq      %%mm2, 16(%0,%1) \n\t"

        "movq      %%mm3, 24(%0,%1) \n\t"

        "jg 1b \n\t"

        :"+r"(i)

        :"r"(z)

    );

    /* pass 2 .. ln-1 */

    nblocks = 1 << (ln-3);

    nloops = 1 << 2;

    cptr = s->exptab1;

    do {

        p = z;

        j = nblocks;

        do {

            i = nloops*8;

            asm volatile(

                "1: \n\t"

                "sub $16, %0 \n\t"

                "movq    (%1,%0), %%mm0 \n\t"

                "movq   8(%1,%0), %%mm1 \n\t"

                "movq    (%2,%0), %%mm2 \n\t"

                "movq   8(%2,%0), %%mm3 \n\t"

                "movq      %%mm2, %%mm4 \n\t"

                "movq      %%mm3, %%mm5 \n\t"

                "punpckldq %%mm2, %%mm2 \n\t"

                "punpckldq %%mm3, %%mm3 \n\t"

                "punpckhdq %%mm4, %%mm4 \n\t"

                "punpckhdq %%mm5, %%mm5 \n\t"

                "pfmul   (%3,%0,2), %%mm2 \n\t" //  cre*re cim*re

                "pfmul  8(%3,%0,2), %%mm3 \n\t"

                "pfmul 16(%3,%0,2), %%mm4 \n\t" // -cim*im cre*im

                "pfmul 24(%3,%0,2), %%mm5 \n\t"

                "pfadd     %%mm2, %%mm4 \n\t" // cre*re-cim*im cim*re+cre*im

                "pfadd     %%mm3, %%mm5 \n\t"

                "movq      %%mm0, %%mm2 \n\t"

                "movq      %%mm1, %%mm3 \n\t"

                "pfadd     %%mm4, %%mm0 \n\t"

                "pfadd     %%mm5, %%mm1 \n\t"

                "pfsub     %%mm4, %%mm2 \n\t"

                "pfsub     %%mm5, %%mm3 \n\t"

                "movq      %%mm0,  (%1,%0) \n\t"

                "movq      %%mm1, 8(%1,%0) \n\t"

                "movq      %%mm2,  (%2,%0) \n\t"

                "movq      %%mm3, 8(%2,%0) \n\t"

                "jg 1b \n\t"

                :"+r"(i)

                :"r"(p), "r"(p + nloops), "r"(cptr)

            );

            p += nloops*2;

        } while (--j);

        cptr += nloops*2;

        nblocks >>= 1;

        nloops <<= 1;

    } while (nblocks != 0);

    asm volatile("femms");

}