/* 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>