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/* Macros to swap the order of bytes in integer values.
Copyright (C) 1997, 1998, 2000, 2002, 2003 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. */
#ifndef _ASM_BITS_BYTESWAP_H
#define _ASM_BITS_BYTESWAP_H 1
#define __bswap_non_constant_16(x) \
(__extension__ \
({ register unsigned short int __v; \
__asm__ ("rorw $8, %w0" \
: "=r" (__v) \
: "0" (x) \
: "cc"); \
__v; }))
/* To swap the bytes in a word the i486 processors and up provide the
`bswap' opcode. On i386 we have to use three instructions. */
#if !defined __i486__ && !defined __pentium__ && !defined __pentiumpro__ \
&& !defined __pentium4__
# define __bswap_non_constant_32(x) \
(__extension__ \
({ register unsigned int __v; \
__asm__ ("rorw $8, %w0;" \
"rorl $16, %0;" \
"rorw $8, %w0" \
: "=r" (__v) \
: "0" (x) \
: "cc"); \
__v; }))
#else
# define __bswap_non_constant_32(x) \
(__extension__ \
({ register unsigned int __v; \
__asm__ ("bswap %0" : "=r" (__v) : "0" (x)); \
__v; }))
#endif
#endif
#include <bits/byteswap-common.h>
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