mpegvideo_mmx.c

mediastreamer2是开源的网络传输媒体流的库

/*
 * The simplest mpeg encoder (well, it was the simplest!)
 * Copyright (c) 2000,2001 Fabrice Bellard.
 *
 * Optimized for ia32 CPUs by Nick Kurshev <[e-mail]>
 * h263, mpeg1, mpeg2 dequantizer & draw_edges by Michael Niedermayer <[e-mail]>
 *
 * 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"
#include "dsputil_mmx.h"
#include "mpegvideo.h"
#include "avcodec.h"
#include "x86_cpu.h"

extern uint16_t inv_zigzag_direct16[64];


static void dct_unquantize_h263_intra_mmx(MpegEncContext *s,
                                  DCTELEM *block, int n, int qscale)
{
    long level, qmul, qadd, nCoeffs;

    qmul = qscale << 1;

    assert(s->block_last_index[n]>=0 || s->h263_aic);

    if (!s->h263_aic) {
        if (n < 4)
            level = block[0] * s->y_dc_scale;
        else
            level = block[0] * s->c_dc_scale;
        qadd = (qscale - 1) | 1;
    }else{
        qadd = 0;
        level= block[0];
    }
    if(s->ac_pred)
        nCoeffs=63;
    else
        nCoeffs= s->inter_scantable.raster_end[ s->block_last_index[n] ];
//printf("%d %d  ", qmul, qadd);
asm volatile(
                "movd %1, %%mm6                 \n\t" //qmul
                "packssdw %%mm6, %%mm6          \n\t"
                "packssdw %%mm6, %%mm6          \n\t"
                "movd %2, %%mm5                 \n\t" //qadd
                "pxor %%mm7, %%mm7              \n\t"
                "packssdw %%mm5, %%mm5          \n\t"
                "packssdw %%mm5, %%mm5          \n\t"
                "psubw %%mm5, %%mm7             \n\t"
                "pxor %%mm4, %%mm4              \n\t"
                ASMALIGN(4)
                "1:                             \n\t"
                "movq (%0, %3), %%mm0           \n\t"
                "movq 8(%0, %3), %%mm1          \n\t"

                "pmullw %%mm6, %%mm0            \n\t"
                "pmullw %%mm6, %%mm1            \n\t"

                "movq (%0, %3), %%mm2           \n\t"
                "movq 8(%0, %3), %%mm3          \n\t"

                "pcmpgtw %%mm4, %%mm2           \n\t" // block[i] < 0 ? -1 : 0
                "pcmpgtw %%mm4, %%mm3           \n\t" // block[i] < 0 ? -1 : 0

                "pxor %%mm2, %%mm0              \n\t"
                "pxor %%mm3, %%mm1              \n\t"

                "paddw %%mm7, %%mm0             \n\t"
                "paddw %%mm7, %%mm1             \n\t"

                "pxor %%mm0, %%mm2              \n\t"
                "pxor %%mm1, %%mm3              \n\t"

                "pcmpeqw %%mm7, %%mm0           \n\t" // block[i] == 0 ? -1 : 0
                "pcmpeqw %%mm7, %%mm1           \n\t" // block[i] == 0 ? -1 : 0

                "pandn %%mm2, %%mm0             \n\t"
                "pandn %%mm3, %%mm1             \n\t"

                "movq %%mm0, (%0, %3)           \n\t"
                "movq %%mm1, 8(%0, %3)          \n\t"

                "add $16, %3                    \n\t"
                "jng 1b                         \n\t"
                ::"r" (block+nCoeffs), "g"(qmul), "g" (qadd), "r" (2*(-nCoeffs))
                : "memory"
        );
        block[0]= level;
}


static void dct_unquantize_h263_inter_mmx(MpegEncContext *s,
                                  DCTELEM *block, int n, int qscale)
{
    long qmul, qadd, nCoeffs;

    qmul = qscale << 1;
    qadd = (qscale - 1) | 1;

    assert(s->block_last_index[n]>=0 || s->h263_aic);

    nCoeffs= s->inter_scantable.raster_end[ s->block_last_index[n] ];
//printf("%d %d  ", qmul, qadd);
asm volatile(
                "movd %1, %%mm6                 \n\t" //qmul
                "packssdw %%mm6, %%mm6          \n\t"
                "packssdw %%mm6, %%mm6          \n\t"
                "movd %2, %%mm5                 \n\t" //qadd
                "pxor %%mm7, %%mm7              \n\t"
                "packssdw %%mm5, %%mm5          \n\t"
                "packssdw %%mm5, %%mm5          \n\t"
                "psubw %%mm5, %%mm7             \n\t"
                "pxor %%mm4, %%mm4              \n\t"
                ASMALIGN(4)
                "1:                             \n\t"
                "movq (%0, %3), %%mm0           \n\t"
                "movq 8(%0, %3), %%mm1          \n\t"

                "pmullw %%mm6, %%mm0            \n\t"
                "pmullw %%mm6, %%mm1            \n\t"

                "movq (%0, %3), %%mm2           \n\t"
                "movq 8(%0, %3), %%mm3          \n\t"

                "pcmpgtw %%mm4, %%mm2           \n\t" // block[i] < 0 ? -1 : 0
                "pcmpgtw %%mm4, %%mm3           \n\t" // block[i] < 0 ? -1 : 0

                "pxor %%mm2, %%mm0              \n\t"
                "pxor %%mm3, %%mm1              \n\t"

                "paddw %%mm7, %%mm0             \n\t"
                "paddw %%mm7, %%mm1             \n\t"

                "pxor %%mm0, %%mm2              \n\t"
                "pxor %%mm1, %%mm3              \n\t"

                "pcmpeqw %%mm7, %%mm0           \n\t" // block[i] == 0 ? -1 : 0
                "pcmpeqw %%mm7, %%mm1           \n\t" // block[i] == 0 ? -1 : 0

                "pandn %%mm2, %%mm0             \n\t"
                "pandn %%mm3, %%mm1             \n\t"

                "movq %%mm0, (%0, %3)           \n\t"
                "movq %%mm1, 8(%0, %3)          \n\t"

                "add $16, %3                    \n\t"
                "jng 1b                         \n\t"
                ::"r" (block+nCoeffs), "g"(qmul), "g" (qadd), "r" (2*(-nCoeffs))
                : "memory"
        );
}


/*
  NK:
  Note: looking at PARANOID:
  "enable all paranoid tests for rounding, overflows, etc..."

#ifdef PARANOID
                if (level < -2048 || level > 2047)
                    fprintf(stderr, "unquant error %d %d\n", i, level);
#endif
  We can suppose that result of two multiplications can't be greater than 0xFFFF
  i.e. is 16-bit, so we use here only PMULLW instruction and can avoid
  a complex multiplication.
=====================================================
 Full formula for multiplication of 2 integer numbers
 which are represent as high:low words:
 input: value1 = high1:low1
        value2 = high2:low2
 output: value3 = value1*value2
 value3=high3:low3 (on overflow: modulus 2^32 wrap-around)
 this mean that for 0x123456 * 0x123456 correct result is 0x766cb0ce4
 but this algorithm will compute only 0x66cb0ce4
 this limited by 16-bit size of operands
 ---------------------------------
 tlow1 = high1*low2
 tlow2 = high2*low1
 tlow1 = tlow1 + tlow2
 high3:low3 = low1*low2
 high3 += tlow1
*/
static void dct_unquantize_mpeg1_intra_mmx(MpegEncContext *s,
                                     DCTELEM *block, int n, int qscale)
{
    long nCoeffs;
    const uint16_t *quant_matrix;
    int block0;

    assert(s->block_last_index[n]>=0);

    nCoeffs= s->intra_scantable.raster_end[ s->block_last_index[n] ]+1;

    if (n < 4)
        block0 = block[0] * s->y_dc_scale;
    else
        block0 = block[0] * s->c_dc_scale;
    /* XXX: only mpeg1 */
    quant_matrix = s->intra_matrix;
asm volatile(
                "pcmpeqw %%mm7, %%mm7           \n\t"
                "psrlw $15, %%mm7               \n\t"
                "movd %2, %%mm6                 \n\t"
                "packssdw %%mm6, %%mm6          \n\t"
                "packssdw %%mm6, %%mm6          \n\t"
                "mov %3, %%"REG_a"              \n\t"
                ASMALIGN(4)
                "1:                             \n\t"
                "movq (%0, %%"REG_a"), %%mm0    \n\t"
                "movq 8(%0, %%"REG_a"), %%mm1   \n\t"
                "movq (%1, %%"REG_a"), %%mm4    \n\t"
                "movq 8(%1, %%"REG_a"), %%mm5   \n\t"
                "pmullw %%mm6, %%mm4            \n\t" // q=qscale*quant_matrix[i]
                "pmullw %%mm6, %%mm5            \n\t" // q=qscale*quant_matrix[i]
                "pxor %%mm2, %%mm2              \n\t"
                "pxor %%mm3, %%mm3              \n\t"
                "pcmpgtw %%mm0, %%mm2           \n\t" // block[i] < 0 ? -1 : 0
                "pcmpgtw %%mm1, %%mm3           \n\t" // block[i] < 0 ? -1 : 0
                "pxor %%mm2, %%mm0              \n\t"
                "pxor %%mm3, %%mm1              \n\t"
                "psubw %%mm2, %%mm0             \n\t" // abs(block[i])
                "psubw %%mm3, %%mm1             \n\t" // abs(block[i])
                "pmullw %%mm4, %%mm0            \n\t" // abs(block[i])*q
                "pmullw %%mm5, %%mm1            \n\t" // abs(block[i])*q
                "pxor %%mm4, %%mm4              \n\t"
                "pxor %%mm5, %%mm5              \n\t" // FIXME slow
                "pcmpeqw (%0, %%"REG_a"), %%mm4 \n\t" // block[i] == 0 ? -1 : 0
                "pcmpeqw 8(%0, %%"REG_a"), %%mm5\n\t" // block[i] == 0 ? -1 : 0
                "psraw $3, %%mm0                \n\t"
                "psraw $3, %%mm1                \n\t"
                "psubw %%mm7, %%mm0             \n\t"
                "psubw %%mm7, %%mm1             \n\t"