mirror of
				https://github.com/ossrs/srs.git
				synced 2025-03-09 15:49:59 +00:00 
			
		
		
		
	
		
			
				
	
	
		
			208 lines
		
	
	
	
		
			7.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			208 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 */
 |