2006-01-10 Roland McGrath <roland@redhat.com>
[kopensolaris-gnu/glibc.git] / sysdeps / s390 / bits / byteswap.h
1 /* Macros to swap the order of bytes in integer values.  s390 version.
2    Copyright (C) 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
3    Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
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
22 # error "Never use <bits/byteswap.h> directly; include <byteswap.h> instead."
23 #endif
24
25 #include <bits/wordsize.h>
26
27 #ifndef _BITS_BYTESWAP_H
28 #define _BITS_BYTESWAP_H 1
29
30 #define __bswap_constant_16(x) \
31      ((((x) >> 8) & 0xff) | (((x) & 0xff) << 8))
32
33 /* Swap bytes in 16 bit value. */
34 #if defined __GNUC__ && __GNUC__ >= 2
35 # if __WORDSIZE == 64
36 #  define __bswap_16(x) \
37      (__extension__                                                           \
38       ({ unsigned short int __v, __x = (x);                                   \
39          if (__builtin_constant_p (x))                                        \
40            __v = __bswap_constant_16 (__x);                                   \
41          else {                                                               \
42            unsigned short int __tmp = (unsigned short int) (__x);             \
43            __asm__ __volatile__ (                                             \
44               "lrvh %0,%1"                                                    \
45               : "=&d" (__v) : "m" (__tmp) );                                  \
46          }                                                                    \
47          __v; }))
48 # else
49 #  define __bswap_16(x) \
50      (__extension__                                                           \
51       ({ unsigned short int __v, __x = (x);                                   \
52          if (__builtin_constant_p (x))                                        \
53            __v = __bswap_constant_16 (__x);                                   \
54          else {                                                               \
55            unsigned short int __tmp = (unsigned short int) (__x);             \
56            __asm__ __volatile__ (                                             \
57               "sr   %0,%0\n"                                                  \
58               "la   1,%1\n"                                                   \
59               "icm  %0,2,1(1)\n"                                              \
60               "ic   %0,0(1)"                                                  \
61               : "=&d" (__v) : "m" (__tmp) : "1");                             \
62          }                                                                    \
63          __v; }))
64 # endif
65 #else
66 /* This is better than nothing.  */
67 static __inline unsigned short int
68 __bswap_16 (unsigned short int __bsx)
69 {
70   return __bswap_constant_16 (__bsx);
71 }
72 #endif
73
74 /* Swap bytes in 32 bit value.  */
75 #define __bswap_constant_32(x) \
76      ((((x) & 0xff000000) >> 24) | (((x) & 0x00ff0000) >>  8) |               \
77       (((x) & 0x0000ff00) <<  8) | (((x) & 0x000000ff) << 24))
78
79 #if defined __GNUC__ && __GNUC__ >= 2
80 # if __WORDSIZE == 64
81 #  define __bswap_32(x) \
82      (__extension__                                                           \
83       ({ unsigned int __v, __x = (x);                                         \
84          if (__builtin_constant_p (x))                                        \
85            __v = __bswap_constant_32 (__x);                                   \
86          else {                                                               \
87            unsigned int __tmp = (unsigned int) (__x);                         \
88            __asm__ __volatile__ (                                             \
89               "lrv   %0,%1"                                                   \
90               : "=&d" (__v) : "m" (__tmp));                                   \
91          }                                                                    \
92          __v; }))
93 # else
94 #  define __bswap_32(x) \
95      (__extension__                                                           \
96       ({ unsigned int __v, __x = (x);                                         \
97          if (__builtin_constant_p (x))                                        \
98            __v = __bswap_constant_32 (__x);                                   \
99          else {                                                               \
100            unsigned int __tmp = (unsigned int) (__x);                         \
101            __asm__ __volatile__ (                                             \
102               "la    1,%1\n"                                                  \
103               "icm   %0,8,3(1)\n"                                             \
104               "icm   %0,4,2(1)\n"                                             \
105               "icm   %0,2,1(1)\n"                                             \
106               "ic    %0,0(1)"                                                 \
107               : "=&d" (__v) : "m" (__tmp) : "1");                             \
108          }                                                                    \
109          __v; }))
110 # endif
111 #else
112 static __inline unsigned int
113 __bswap_32 (unsigned int __bsx)
114 {
115   return __bswap_constant_32 (__bsx);
116 }
117 #endif
118
119 /* Swap bytes in 64 bit value.  */
120 #define __bswap_constant_64(x) \
121      ((((x)&0xff00000000000000) >> 56) | (((x)&0x00ff000000000000) >> 40) |  \
122       (((x)&0x0000ff0000000000) >> 24) | (((x)&0x000000ff00000000) >>  8) |  \
123       (((x)&0x00000000ff000000) <<  8) | (((x)&0x0000000000ff0000) << 24) |  \
124       (((x)&0x000000000000ff00) << 40) | (((x)&0x00000000000000ff) << 56))
125
126 #if defined __GNUC__ && __GNUC__ >= 2
127 # if __WORDSIZE == 64
128 #  define __bswap_64(x) \
129      (__extension__                                                           \
130       ({ unsigned long __w, __x = (x);                                        \
131          if (__builtin_constant_p (x))                                        \
132            __w = __bswap_constant_64 (__x);                                   \
133          else {                                                               \
134            unsigned long __tmp = (unsigned long) (__x);                       \
135            __asm__ __volatile__ (                                             \
136               "lrvg  %0,%1"                                                   \
137               : "=&d" (__w) : "m" (__tmp));                                   \
138          }                                                                    \
139          __w; }))
140 # else
141 #  define __bswap_64(x) \
142      __extension__                                      \
143        ({ union { unsigned long long int __ll;          \
144                   unsigned long int __l[2]; } __w, __r; \
145           __w.__ll = (x);                               \
146           __r.__l[0] = __bswap_32 (__w.__l[1]);         \
147           __r.__l[1] = __bswap_32 (__w.__l[0]);         \
148           __r.__ll; })
149 # endif
150 #else
151 static __inline unsigned long long int
152 __bswap_64 (unsigned long long int __bsx)
153 {
154   return __bswap_constant_64 (__bsx);
155 }
156 #endif
157
158 #endif /* _BITS_BYTESWAP_H */