1/* 2 * This file is part of Libav. 3 * 4 * Libav is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Lesser General Public 6 * License as published by the Free Software Foundation; either 7 * version 2.1 of the License, or (at your option) any later version. 8 * 9 * Libav is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * Lesser General Public License for more details. 13 * 14 * You should have received a copy of the GNU Lesser General Public 15 * License along with Libav; if not, write to the Free Software 16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 17 */ 18 19/** 20 * @file 21 * byte swapping routines 22 */ 23 24#ifndef AVUTIL_X86_BSWAP_H 25#define AVUTIL_X86_BSWAP_H 26 27#include <stdint.h> 28#include "config.h" 29#include "libavutil/attributes.h" 30 31#if !AV_GCC_VERSION_AT_LEAST(4,1) 32#define av_bswap16 av_bswap16 33static av_always_inline av_const unsigned av_bswap16(unsigned x) 34{ 35 __asm__("rorw $8, %w0" : "+r"(x)); 36 return x; 37} 38#endif /* !AV_GCC_VERSION_AT_LEAST(4,1) */ 39 40#if !AV_GCC_VERSION_AT_LEAST(4,5) 41#define av_bswap32 av_bswap32 42static av_always_inline av_const uint32_t av_bswap32(uint32_t x) 43{ 44 __asm__("bswap %0" : "+r" (x)); 45 return x; 46} 47 48#if ARCH_X86_64 49#define av_bswap64 av_bswap64 50static inline uint64_t av_const av_bswap64(uint64_t x) 51{ 52 __asm__("bswap %0": "=r" (x) : "0" (x)); 53 return x; 54} 55#endif 56#endif /* !AV_GCC_VERSION_AT_LEAST(4,5) */ 57 58#endif /* AVUTIL_X86_BSWAP_H */ 59