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/* Macros to swap the order of bytes in integer values. m68k version.
Copyright (C) 1997, 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library 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.
The GNU C Library 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 the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#if !defined _BYTESWAP_H && !defined _NETINET_IN_H
# error "Never use <bits/byteswap.h> directly; include <byteswap.h> instead."
#endif
#ifndef _BITS_BYTESWAP_H
#define _BITS_BYTESWAP_H 1
/* Swap bytes in 16 bit value. We don't provide an assembler version
because GCC is smart enough to generate optimal assembler output, and
this allows for better cse. */
#define __bswap_16(x) \
((((x) >> 8) & 0xff) | (((x) & 0xff) << 8))
/* Swap bytes in 32 bit value. */
#define __bswap_constant_32(x) \
((((x) & 0xff000000) >> 24) | (((x) & 0x00ff0000) >> 8) | \
(((x) & 0x0000ff00) << 8) | (((x) & 0x000000ff) << 24))
#if defined __GNUC__ && __GNUC__ >= 2
# define __bswap_32(x) \
__extension__ \
({ unsigned int __bswap_32_v; \
if (__builtin_constant_p (x)) \
__bswap_32_v = __bswap_constant_32 (x); \
else \
__asm__ __volatile__ ("ror%.w %#8, %0;" \
"swap %0;" \
"ror%.w %#8, %0" \
: "=d" (__bswap_32_v) \
: "0" ((unsigned int) (x))); \
__bswap_32_v; })
#else
# define __bswap_32(x) __bswap_constant_32 (x)
#endif
#if defined __GNUC__ && __GNUC__ >= 2
/* Swap bytes in 64 bit value. */
# define __bswap_64(x) \
__extension__ \
({ union { unsigned long long int __ll; \
unsigned long int __l[2]; } __bswap_64_v, __bswap_64_r; \
__bswap_64_v.__ll = (x); \
__bswap_64_r.__l[0] = __bswap_32 (__bswap_64_v.__l[1]); \
__bswap_64_r.__l[1] = __bswap_32 (__bswap_64_v.__l[0]); \
__bswap_64_r.__ll; })
#endif
#endif /* _BITS_BYTESWAP_H */
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