rockbox/firmware/include/rbendian.h

188 lines
5.8 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2002 by Alan Korr
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef _RBENDIAN_H_
#define _RBENDIAN_H_
#include "config.h"
#ifdef OS_USE_BYTESWAP_H
#include <byteswap.h>
#endif
#ifndef __MINGW32__
#include <endian.h>
#endif
/* clear these out since we redefine them to be truely constant compatible */
#undef swap16
#undef swap32
#undef swap64
#undef letoh16
#undef letoh32
#undef letoh64
#undef htole16
#undef htole32
#undef htole64
#undef betoh16
#undef betoh32
#undef betoh64
#undef htobe16
#undef htobe32
#undef htobe64
/* static/generic endianness conversion */
#define SWAP16_CONST(x) \
((typeof(x))( ((uint16_t)(x) >> 8) | ((uint16_t)(x) << 8) ))
#define SWAP32_CONST(x) \
((typeof(x))( (((uint32_t)(x) & 0xff000000) >> 24) | \
(((uint32_t)(x) & 0x00ff0000) >> 8) | \
(((uint32_t)(x) & 0x0000ff00) << 8) | \
(((uint32_t)(x) & 0x000000ff) << 24) ))
#define SWAP64_CONST(x) \
((typeof(x))( (((uint64_t)(x) & 0xff00000000000000ull) >> 56) | \
(((uint64_t)(x) & 0x00ff000000000000ull) >> 40) | \
(((uint64_t)(x) & 0x0000ff0000000000ull) >> 24) | \
(((uint64_t)(x) & 0x000000ff00000000ull) >> 8) | \
(((uint64_t)(x) & 0x00000000ff000000ull) << 8) | \
(((uint64_t)(x) & 0x0000000000ff0000ull) << 24) | \
(((uint64_t)(x) & 0x000000000000ff00ull) << 40) | \
(((uint64_t)(x) & 0x00000000000000ffull) << 56) ))
#define SWAP_ODD_EVEN32_CONST(x) \
((typeof(x))( ((uint32_t)SWAP16_CONST((uint32_t)(x) >> 16) << 16) | \
SWAP16_CONST((uint32_t)(x))) )
#define SWAW32_CONST(x) \
((typeof(x))( ((uint32_t)(x) << 16) | ((uint32_t)(x) >> 16) ))
#ifndef __ENDIAN_H_NATIVE_RB
#if defined (__bswap_16)
#define __swap16_os(x) __bswap_16(x)
#define __swap32_os(x) __bswap_32(x)
#define __swap64_os(x) __bswap_64(x)
#elif defined (bswap_16)
#define __swap16_os(x) bswap_16(x)
#define __swap32_os(x) bswap_32(x)
#define __swap64_os(x) bswap_64(x)
#elif defined (__swap16)
#define __swap16_os(x) __swap16(x)
#define __swap32_os(x) __swap32(x)
#define __swap64_os(x) __swap64(x)
#elif defined (swap16)
#define __swap16_os(x) swap16(x)
#define __swap32_os(x) swap32(x)
#define __swap64_os(x) swap64(x)
#else
/* kinda hacky but works */
#define __swap16_os(x) SWAP16_CONST(x)
#define __swap32_os(x) SWAP32_CONST(x)
#define __swap64_os(x) SWAP64_CONST(x)
#endif
/* wrap these because they aren't always compatible with compound initializers */
static FORCE_INLINE uint16_t swap16_hw(uint16_t x)
{ return __swap16_os(x); }
static FORCE_INLINE uint32_t swap32_hw(uint32_t x)
{ return __swap32_os(x); }
static FORCE_INLINE uint64_t swap64_hw(uint64_t x)
{ return __swap64_os(x); }
#endif /* __ENDIAN_H_NATIVE_RB */
#if defined(NEED_GENERIC_BYTESWAPS) || !defined(__ENDIAN_H_NATIVE_RB)
/* these are uniquely ours it seems */
static inline uint32_t swap_odd_even32_hw(uint32_t value)
/*
* result[31..24],[15.. 8] = value[23..16],[ 7.. 0]
* result[23..16],[ 7.. 0] = value[31..24],[15.. 8]
*/
{
uint32_t t = value & 0xff00ff00;
return (t >> 8) | ((t ^ value) << 8);
}
static inline uint32_t swaw32_hw(uint32_t value)
/*
* result[31..16] = value[15.. 0];
* result[15.. 0] = value[31..16];
*/
{
return (value >> 16) | (value << 16);
}
#endif /* Generic */
/* select best method based upon whether x is a constant expression */
#define swap16(x) \
( __builtin_constant_p(x) ? SWAP16_CONST(x) : (typeof(x))swap16_hw(x) )
#define swap32(x) \
( __builtin_constant_p(x) ? SWAP32_CONST(x) : (typeof(x))swap32_hw(x) )
#define swap64(x) \
( __builtin_constant_p(x) ? SWAP64_CONST(x) : (typeof(x))swap64_hw(x) )
#define swap_odd_even32(x) \
( __builtin_constant_p(x) ? SWAP_ODD_EVEN32_CONST(x) : (typeof(x))swap_odd_even32_hw(x) )
#define swaw32(x) \
( __builtin_constant_p(x) ? SWAW32_CONST(x) : (typeof(x))swaw32_hw(x) )
#if defined(ROCKBOX_LITTLE_ENDIAN)
#define letoh16(x) (x)
#define letoh32(x) (x)
#define letoh64(x) (x)
#define htole16(x) (x)
#define htole32(x) (x)
#define htole64(x) (x)
#define betoh16(x) swap16(x)
#define betoh32(x) swap32(x)
#define betoh64(x) swap64(x)
#define htobe16(x) swap16(x)
#define htobe32(x) swap32(x)
#define htobe64(x) swap64(x)
#define swap_odd_even_be32(x) (x)
#define swap_odd_even_le32(x) swap_odd_even32(x)
#elif defined(ROCKBOX_BIG_ENDIAN)
#define letoh16(x) swap16(x)
#define letoh32(x) swap32(x)
#define letoh64(x) swap64(x)
#define htole16(x) swap16(x)
#define htole32(x) swap32(x)
#define htole64(x) swap64(x)
#define betoh16(x) (x)
#define betoh32(x) (x)
#define betoh64(x) (x)
#define htobe16(x) (x)
#define htobe32(x) (x)
#define htobe64(x) (x)
#define swap_odd_even_be32(x) swap_odd_even32(x)
#define swap_odd_even_le32(x) (x)
#else
#error "Unknown endianness!"
#endif
#endif /* _RBENDIAN_H_ */