FFmpeg/libavutil/bswap.h
Mans Rullgard f64c2e710f bswap: make generic implementation more compiler-friendly
With these changes, gcc 4.5 and later recognise it as a bswap
and use the proper instructions on ARM and x86.  On x86, the
16-bit bswap is recognised from gcc 4.1.

Signed-off-by: Mans Rullgard <mans@mansr.com>
2011-12-12 12:14:14 +00:00

110 lines
2.8 KiB
C

/*
* copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* byte swapping routines
*/
#ifndef AVUTIL_BSWAP_H
#define AVUTIL_BSWAP_H
#include <stdint.h>
#include "libavutil/avconfig.h"
#include "attributes.h"
#ifdef HAVE_AV_CONFIG_H
#include "config.h"
#if ARCH_ARM
# include "arm/bswap.h"
#elif ARCH_AVR32
# include "avr32/bswap.h"
#elif ARCH_BFIN
# include "bfin/bswap.h"
#elif ARCH_SH4
# include "sh4/bswap.h"
#elif ARCH_X86
# include "x86/bswap.h"
#endif
#endif /* HAVE_AV_CONFIG_H */
#define AV_BSWAP16C(x) (((x) << 8 & 0xff00) | ((x) >> 8 & 0x00ff))
#define AV_BSWAP32C(x) (AV_BSWAP16C(x) << 16 | AV_BSWAP16C((x) >> 16))
#define AV_BSWAP64C(x) (AV_BSWAP32C(x) << 32 | AV_BSWAP32C((x) >> 32))
#define AV_BSWAPC(s, x) AV_BSWAP##s##C(x)
#ifndef av_bswap16
static av_always_inline av_const uint16_t av_bswap16(uint16_t x)
{
x= (x>>8) | (x<<8);
return x;
}
#endif
#ifndef av_bswap32
static av_always_inline av_const uint32_t av_bswap32(uint32_t x)
{
return AV_BSWAP32C(x);
}
#endif
#ifndef av_bswap64
static inline uint64_t av_const av_bswap64(uint64_t x)
{
return (uint64_t)av_bswap32(x) << 32 | av_bswap32(x >> 32);
}
#endif
// be2ne ... big-endian to native-endian
// le2ne ... little-endian to native-endian
#if AV_HAVE_BIGENDIAN
#define av_be2ne16(x) (x)
#define av_be2ne32(x) (x)
#define av_be2ne64(x) (x)
#define av_le2ne16(x) av_bswap16(x)
#define av_le2ne32(x) av_bswap32(x)
#define av_le2ne64(x) av_bswap64(x)
#define AV_BE2NEC(s, x) (x)
#define AV_LE2NEC(s, x) AV_BSWAPC(s, x)
#else
#define av_be2ne16(x) av_bswap16(x)
#define av_be2ne32(x) av_bswap32(x)
#define av_be2ne64(x) av_bswap64(x)
#define av_le2ne16(x) (x)
#define av_le2ne32(x) (x)
#define av_le2ne64(x) (x)
#define AV_BE2NEC(s, x) AV_BSWAPC(s, x)
#define AV_LE2NEC(s, x) (x)
#endif
#define AV_BE2NE16C(x) AV_BE2NEC(16, x)
#define AV_BE2NE32C(x) AV_BE2NEC(32, x)
#define AV_BE2NE64C(x) AV_BE2NEC(64, x)
#define AV_LE2NE16C(x) AV_LE2NEC(16, x)
#define AV_LE2NE32C(x) AV_LE2NEC(32, x)
#define AV_LE2NE64C(x) AV_LE2NEC(64, x)
#endif /* AVUTIL_BSWAP_H */