📄 mpegvideo_mmx.c
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/*
* The simplest mpeg encoder (well, it was the simplest!)
* Copyright (c) 2000,2001 Fabrice Bellard.
*
* Optimized for ia32 CPUs by Nick Kurshev <nickols_k@mail.ru>
* h263, mpeg1, mpeg2 dequantizer & draw_edges by Michael Niedermayer <michaelni@gmx.at>
*
* 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 "mpegvideo.h"
#include "avcodec.h"
#include "x86_cpu.h"
extern uint16_t inv_zigzag_direct16[64];
static const unsigned long long int mm_wabs __attribute__ ((aligned(8))) = 0xffffffffffffffffULL;
static const unsigned long long int mm_wone __attribute__ ((aligned(8))) = 0x0001000100010001ULL;
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 greate of 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"
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