FFmpeg/libavcodec/x86/pngdsp-init.c

/*
 * x86 PNG optimizations.
 * Copyright (c) 2008 Loren Merrit <lorenm@u.washington.edu>
 *
 * This file is part of Libav.
 *
 * Libav 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.
 *
 * Libav 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 Libav; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libavutil/cpu.h"
#include "libavutil/x86_cpu.h"
#include "libavcodec/pngdsp.h"
#include "dsputil_mmx.h"

#define PAETH(cpu, abs3)\
static void add_png_paeth_prediction_##cpu(uint8_t *dst, uint8_t *src, uint8_t *top, int w, int bpp)\
{\
    x86_reg i = -bpp;\
    x86_reg end = w-3;\
    __asm__ volatile(\
        "pxor      %%mm7, %%mm7 \n"\
        "movd    (%1,%0), %%mm0 \n"\
        "movd    (%2,%0), %%mm1 \n"\
        "punpcklbw %%mm7, %%mm0 \n"\
        "punpcklbw %%mm7, %%mm1 \n"\
        "add       %4, %0 \n"\
        "1: \n"\
        "movq      %%mm1, %%mm2 \n"\
        "movd    (%2,%0), %%mm1 \n"\
        "movq      %%mm2, %%mm3 \n"\
        "punpcklbw %%mm7, %%mm1 \n"\
        "movq      %%mm2, %%mm4 \n"\
        "psubw     %%mm1, %%mm3 \n"\
        "psubw     %%mm0, %%mm4 \n"\
        "movq      %%mm3, %%mm5 \n"\
        "paddw     %%mm4, %%mm5 \n"\
        abs3\
        "movq      %%mm4, %%mm6 \n"\
        "pminsw    %%mm5, %%mm6 \n"\
        "pcmpgtw   %%mm6, %%mm3 \n"\
        "pcmpgtw   %%mm5, %%mm4 \n"\
        "movq      %%mm4, %%mm6 \n"\
        "pand      %%mm3, %%mm4 \n"\
        "pandn     %%mm3, %%mm6 \n"\
        "pandn     %%mm0, %%mm3 \n"\
        "movd    (%3,%0), %%mm0 \n"\
        "pand      %%mm1, %%mm6 \n"\
        "pand      %%mm4, %%mm2 \n"\
        "punpcklbw %%mm7, %%mm0 \n"\
        "movq      %6,    %%mm5 \n"\
        "paddw     %%mm6, %%mm0 \n"\
        "paddw     %%mm2, %%mm3 \n"\
        "paddw     %%mm3, %%mm0 \n"\
        "pand      %%mm5, %%mm0 \n"\
        "movq      %%mm0, %%mm3 \n"\
        "packuswb  %%mm3, %%mm3 \n"\
        "movd      %%mm3, (%1,%0) \n"\
        "add       %4, %0 \n"\
        "cmp       %5, %0 \n"\
        "jle 1b \n"\
        :"+r"(i)\
        :"r"(dst), "r"(top), "r"(src), "r"((x86_reg)bpp), "g"(end),\
         "m"(ff_pw_255)\
        :"memory"\
    );\
}

#define ABS3_MMX2\
        "psubw     %%mm5, %%mm7 \n"\
        "pmaxsw    %%mm7, %%mm5 \n"\
        "pxor      %%mm6, %%mm6 \n"\
        "pxor      %%mm7, %%mm7 \n"\
        "psubw     %%mm3, %%mm6 \n"\
        "psubw     %%mm4, %%mm7 \n"\
        "pmaxsw    %%mm6, %%mm3 \n"\
        "pmaxsw    %%mm7, %%mm4 \n"\
        "pxor      %%mm7, %%mm7 \n"

#define ABS3_SSSE3\
        "pabsw     %%mm3, %%mm3 \n"\
        "pabsw     %%mm4, %%mm4 \n"\
        "pabsw     %%mm5, %%mm5 \n"

PAETH(mmx2, ABS3_MMX2)
#if HAVE_SSSE3
PAETH(ssse3, ABS3_SSSE3)
#endif

static void add_bytes_l2_mmx(uint8_t *dst, uint8_t *src1, uint8_t *src2, int w)
{
    x86_reg i=0;

    __asm__ volatile(
        "jmp 2f                         \n\t"
        "1:                             \n\t"
        "movq   (%2, %0), %%mm0         \n\t"
        "movq  8(%2, %0), %%mm1         \n\t"
        "paddb  (%3, %0), %%mm0         \n\t"
        "paddb 8(%3, %0), %%mm1         \n\t"
        "movq %%mm0,  (%1, %0)          \n\t"
        "movq %%mm1, 8(%1, %0)          \n\t"
        "add $16, %0                    \n\t"
        "2:                             \n\t"
        "cmp %4, %0                     \n\t"
        " js 1b                         \n\t"
        : "+r" (i)
        : "r"(dst), "r"(src1), "r"(src2), "r"((x86_reg) w - 15)
    );
    for (; i < w; i++)
        dst[i] = src1[i] + src2[i];
}

void ff_pngdsp_init_x86(PNGDSPContext *dsp)
{
    int flags = av_get_cpu_flags();

    if (flags & AV_CPU_FLAG_MMX)
        dsp->add_bytes_l2         = add_bytes_l2_mmx;
    if (flags & AV_CPU_FLAG_MMX2)
        dsp->add_paeth_prediction = add_png_paeth_prediction_mmx2;
    if (flags & AV_CPU_FLAG_SSSE3)
        dsp->add_paeth_prediction = add_png_paeth_prediction_ssse3;
}