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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, see
- <http://www.gnu.org/licenses/>. */
- #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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