sysdeps/ia64/bits/byteswap.h

   1 /* Macros to swap the order of bytes in integer values.
   2    Copyright (C) 1997,1998,2000,2002,2003,2008,2011
   3    Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #if !defined _BYTESWAP_H && !defined _NETINET_IN_H && !defined _ENDIAN_H
  22 # error "Never use <bits/byteswap.h> directly; include <byteswap.h> instead."
  23 #endif
  24
  25 #ifndef _BITS_BYTESWAP_H
  26 #define _BITS_BYTESWAP_H 1
  27
  28 /* Swap bytes in 16 bit value.  */
  29 #define __bswap_constant_16(x) \
  30      ((((x) >> 8) & 0xff) | (((x) & 0xff) << 8))
  31
  32 #if defined __GNUC__ && __GNUC__ >= 2
  33 # define __bswap_16(x) \
  34      (__extension__                                                           \
  35       ({ register unsigned short int __v, __x = (x);                          \
  36          if (__builtin_constant_p (x))                                        \
  37            __v = __bswap_constant_16 (__x);                                   \
  38          else                                                                 \
  39            __asm__ __volatile__ ("shl %0 = %1, 48 ;;"                         \
  40                                  "mux1 %0 = %0, @rev ;;"                      \
  41                                  : "=r" (__v)                                 \
  42                                  : "r" ((unsigned short int) (__x)));         \
  43          __v; }))
  44 #else
  45 /* This is better than nothing.  */
  46 static __inline unsigned short int
  47 __bswap_16 (unsigned short int __bsx)
  48 {
  49   return __bswap_constant_16 (__bsx);
  50 }
  51 #endif
  52
  53
  54 /* Swap bytes in 32 bit value.  */
  55 #define __bswap_constant_32(x) \
  56      ((((x) & 0xff000000) >> 24) | (((x) & 0x00ff0000) >>  8) |               \
  57       (((x) & 0x0000ff00) <<  8) | (((x) & 0x000000ff) << 24))
  58
  59 #if defined __GNUC__ && __GNUC__ >= 2
  60 # define __bswap_32(x) \
  61      (__extension__                                                           \
  62       ({ register unsigned int __v, __x = (x);                                \
  63          if (__builtin_constant_p (x))                                        \
  64            __v = __bswap_constant_32 (__x);                                   \
  65          else                                                                 \
  66            __asm__ __volatile__ ("shl %0 = %1, 32 ;;"                         \
  67                                  "mux1 %0 = %0, @rev ;;"                      \
  68                                  : "=r" (__v)                                 \
  69                                  : "r" ((unsigned int) (__x)));               \
  70          __v; }))
  71 #else
  72 static __inline unsigned int
  73 __bswap_32 (unsigned int __bsx)
  74 {
  75   return __bswap_constant_32 (__bsx);
  76 }
  77 #endif
  78
  79
  80 /* Swap bytes in 64 bit value.  */
  81 #if defined __GNUC__ && __GNUC__ >= 2
  82 # define __bswap_constant_64(x) \
  83      (__extension__ ((((x) & 0xff00000000000000ul) >> 56)                     \
  84                      | (((x) & 0x00ff000000000000ul) >>  40)                  \
  85                      | (((x) & 0x0000ff0000000000ul) >> 24)                   \
  86                      | (((x) & 0x000000ff00000000ul) >> 8)                    \
  87                      | (((x) & 0x00000000ff000000ul) << 8)                    \
  88                      | (((x) & 0x0000000000ff0000ul) << 24)                   \
  89                      | (((x) & 0x000000000000ff00ul) << 40)                   \
  90                      | (((x) & 0x00000000000000fful) << 56)))
  91
  92 # define __bswap_64(x) \
  93      (__extension__                                                           \
  94       ({ register unsigned long int __v, __x = (x);                           \
  95          if (__builtin_constant_p (x))                                        \
  96            __v = __bswap_constant_64 (__x);                                   \
  97          else                                                                 \
  98            __asm__ __volatile__ ("mux1 %0 = %1, @rev ;;"                      \
  99                                  : "=r" (__v)                                 \
 100                                  : "r" ((unsigned long int) (__x)));          \
 101          __v; }))
 102
 103 #else
 104 # define __bswap_constant_64(x) \
 105      ((((x) & 0xff00000000000000ul) >> 56)                                    \
 106       | (((x) & 0x00ff000000000000ul) >>  40)                                 \
 107       | (((x) & 0x0000ff0000000000ul) >> 24)                                  \
 108       | (((x) & 0x000000ff00000000ul) >> 8)                                   \
 109       | (((x) & 0x00000000ff000000ul) << 8)                                   \
 110       | (((x) & 0x0000000000ff0000ul) << 24)                                  \
 111       | (((x) & 0x000000000000ff00ul) << 40)                                  \
 112       | (((x) & 0x00000000000000fful) << 56))
 113
 114 static __inline unsigned long int
 115 __bswap_64 (unsigned long int __bsx)
 116 {
 117   return __bswap_constant_64 (__bsx);
 118 }
 119 #endif
 120
 121 #endif /* _BITS_BYTESWAP_H */