libc/arch-x86/include/machine/endian.h

   1 /*      $OpenBSD: endian.h,v 1.17 2011/03/12 04:03:04 guenther Exp $    */
   2
   3 /*-
   4  * Copyright (c) 1997 Niklas Hallqvist.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #ifndef _MACHINE_ENDIAN_H_
  28 #define _MACHINE_ENDIAN_H_
  29
  30 #ifdef __GNUC__
  31
  32 #define __swap32md(x) __statement({                                     \
  33         uint32_t __swap32md_x = (x);                                    \
  34                                                                         \
  35         __asm ("bswap %0" : "+r" (__swap32md_x));                       \
  36         __swap32md_x;                                                   \
  37 })
  38
  39 #define __swap64md(x) __statement({                                     \
  40         uint64_t __swap64md_x = (x);                                    \
  41                                                                         \
  42         (uint64_t)__swap32md(__swap64md_x >> 32) |                      \
  43             (uint64_t)__swap32md(__swap64md_x & 0xffffffff) << 32;      \
  44 })
  45 #define __swap16md(x) __statement({                                     \
  46         uint16_t __swap16md_x = (x);                                    \
  47                                                                         \
  48         __asm ("rorw $8, %w0" : "+r" (__swap16md_x));                   \
  49         __swap16md_x;                                                   \
  50 })
  51
  52 /* Tell sys/endian.h we have MD variants of the swap macros.  */
  53 #define MD_SWAP
  54
  55 #endif  /* __GNUC__ */
  56
  57 #define _BYTE_ORDER _LITTLE_ENDIAN
  58 #include <sys/types.h>
  59 #include <sys/endian.h>
  60
  61 #endif /* _MACHINE_ENDIAN_H_ */