FFmpeg4/libavcodec/x86/h264_cabac.c

209 lines
7.9 KiB
C

/*
* H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
* Copyright (c) 2003 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
*/
/**
* @file
* H.264 / AVC / MPEG-4 part10 codec.
* non-SIMD x86-specific optimizations for H.264
* @author Michael Niedermayer <michaelni@gmx.at>
*/
#include <stddef.h>
#include "libavcodec/cabac.h"
#include "cabac.h"
#if HAVE_INLINE_ASM
#if ARCH_X86_64
#define REG64 "r"
#else
#define REG64 "m"
#endif
//FIXME use some macros to avoid duplicating get_cabac (cannot be done yet
//as that would make optimization work hard)
#if HAVE_7REGS && !BROKEN_COMPILER
#define decode_significance decode_significance_x86
static int decode_significance_x86(CABACContext *c, int max_coeff,
uint8_t *significant_coeff_ctx_base,
int *index, x86_reg last_off){
void *end= significant_coeff_ctx_base + max_coeff - 1;
int minusstart= -(intptr_t)significant_coeff_ctx_base;
int minusindex= 4-(intptr_t)index;
int bit;
x86_reg coeff_count;
#ifdef BROKEN_RELOCATIONS
void *tables;
__asm__ volatile(
"lea "MANGLE(ff_h264_cabac_tables)", %0 \n\t"
: "=&r"(tables)
: NAMED_CONSTRAINTS_ARRAY(ff_h264_cabac_tables)
);
#endif
__asm__ volatile(
"3: \n\t"
BRANCHLESS_GET_CABAC("%4", "%q4", "(%1)", "%3", "%w3",
"%5", "%q5", "%k0", "%b0",
"%c11(%6)", "%c12(%6)",
AV_STRINGIFY(H264_NORM_SHIFT_OFFSET),
AV_STRINGIFY(H264_LPS_RANGE_OFFSET),
AV_STRINGIFY(H264_MLPS_STATE_OFFSET),
"%13")
"test $1, %4 \n\t"
" jz 4f \n\t"
"add %10, %1 \n\t"
BRANCHLESS_GET_CABAC("%4", "%q4", "(%1)", "%3", "%w3",
"%5", "%q5", "%k0", "%b0",
"%c11(%6)", "%c12(%6)",
AV_STRINGIFY(H264_NORM_SHIFT_OFFSET),
AV_STRINGIFY(H264_LPS_RANGE_OFFSET),
AV_STRINGIFY(H264_MLPS_STATE_OFFSET),
"%13")
"sub %10, %1 \n\t"
"mov %2, %0 \n\t"
"movl %7, %%ecx \n\t"
"add %1, %%"FF_REG_c" \n\t"
"movl %%ecx, (%0) \n\t"
"test $1, %4 \n\t"
" jnz 5f \n\t"
"add"FF_OPSIZE" $4, %2 \n\t"
"4: \n\t"
"add $1, %1 \n\t"
"cmp %8, %1 \n\t"
" jb 3b \n\t"
"mov %2, %0 \n\t"
"movl %7, %%ecx \n\t"
"add %1, %%"FF_REG_c" \n\t"
"movl %%ecx, (%0) \n\t"
"5: \n\t"
"add %9, %k0 \n\t"
"shr $2, %k0 \n\t"
: "=&q"(coeff_count), "+r"(significant_coeff_ctx_base), "+m"(index),
"+&r"(c->low), "=&r"(bit), "+&r"(c->range)
: "r"(c), "m"(minusstart), "m"(end), "m"(minusindex), "m"(last_off),
"i"(offsetof(CABACContext, bytestream)),
"i"(offsetof(CABACContext, bytestream_end))
TABLES_ARG
: "%"FF_REG_c, "memory"
);
return coeff_count;
}
#define decode_significance_8x8 decode_significance_8x8_x86
static int decode_significance_8x8_x86(CABACContext *c,
uint8_t *significant_coeff_ctx_base,
int *index, uint8_t *last_coeff_ctx_base, const uint8_t *sig_off){
int minusindex= 4-(intptr_t)index;
int bit;
x86_reg coeff_count;
x86_reg last=0;
x86_reg state;
#ifdef BROKEN_RELOCATIONS
void *tables;
__asm__ volatile(
"lea "MANGLE(ff_h264_cabac_tables)", %0 \n\t"
: "=&r"(tables)
: NAMED_CONSTRAINTS_ARRAY(ff_h264_cabac_tables)
);
#endif
__asm__ volatile(
"mov %1, %6 \n\t"
"3: \n\t"
"mov %10, %0 \n\t"
"movzb (%0, %6), %6 \n\t"
"add %9, %6 \n\t"
BRANCHLESS_GET_CABAC("%4", "%q4", "(%6)", "%3", "%w3",
"%5", "%q5", "%k0", "%b0",
"%c12(%7)", "%c13(%7)",
AV_STRINGIFY(H264_NORM_SHIFT_OFFSET),
AV_STRINGIFY(H264_LPS_RANGE_OFFSET),
AV_STRINGIFY(H264_MLPS_STATE_OFFSET),
"%15")
"mov %1, %6 \n\t"
"test $1, %4 \n\t"
" jz 4f \n\t"
#ifdef BROKEN_RELOCATIONS
"movzb %c14(%15, %q6), %6\n\t"
#else
"movzb "MANGLE(ff_h264_cabac_tables)"+%c14(%6), %6\n\t"
#endif
"add %11, %6 \n\t"
BRANCHLESS_GET_CABAC("%4", "%q4", "(%6)", "%3", "%w3",
"%5", "%q5", "%k0", "%b0",
"%c12(%7)", "%c13(%7)",
AV_STRINGIFY(H264_NORM_SHIFT_OFFSET),
AV_STRINGIFY(H264_LPS_RANGE_OFFSET),
AV_STRINGIFY(H264_MLPS_STATE_OFFSET),
"%15")
"mov %2, %0 \n\t"
"mov %1, %6 \n\t"
"mov %k6, (%0) \n\t"
"test $1, %4 \n\t"
" jnz 5f \n\t"
"add"FF_OPSIZE" $4, %2 \n\t"
"4: \n\t"
"add $1, %6 \n\t"
"mov %6, %1 \n\t"
"cmp $63, %6 \n\t"
" jb 3b \n\t"
"mov %2, %0 \n\t"
"mov %k6, (%0) \n\t"
"5: \n\t"
"addl %8, %k0 \n\t"
"shr $2, %k0 \n\t"
: "=&q"(coeff_count), "+"REG64(last), "+"REG64(index), "+&r"(c->low),
"=&r"(bit), "+&r"(c->range), "=&r"(state)
: "r"(c), "m"(minusindex), "m"(significant_coeff_ctx_base),
REG64(sig_off), REG64(last_coeff_ctx_base),
"i"(offsetof(CABACContext, bytestream)),
"i"(offsetof(CABACContext, bytestream_end)),
"i"(H264_LAST_COEFF_FLAG_OFFSET_8x8_OFFSET) TABLES_ARG
: "%"FF_REG_c, "memory"
);
return coeff_count;
}
#endif /* HAVE_7REGS && BROKEN_COMPILER */
#endif /* HAVE_INLINE_ASM */