sim/ppc/ppc-endian.h

   1 /*  This file is part of the program psim.
   2
   3     Copyright (C) 1994-1995, Andrew Cagney <cagney@highland.com.au>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, write to the Free Software
  17     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18
  19     */
  20
  21
  22 #ifndef _ENDIAN_H_
  23 #define _ENDIAN_H_
  24
  25 /* C byte conversion functions */
  26
  27 extern unsigned_1 endian_h2t_1(unsigned_1 x);
  28 extern unsigned_2 endian_h2t_2(unsigned_2 x);
  29 extern unsigned_4 endian_h2t_4(unsigned_4 x);
  30 extern unsigned_8 endian_h2t_8(unsigned_8 x);
  31
  32 extern unsigned_1 endian_t2h_1(unsigned_1 x);
  33 extern unsigned_2 endian_t2h_2(unsigned_2 x);
  34 extern unsigned_4 endian_t2h_4(unsigned_4 x);
  35 extern unsigned_8 endian_t2h_8(unsigned_8 x);
  36
  37 /* Host dependant:
  38
  39    The CPP below defines information about the compilation host.  In
  40    particular it defines the macro's:
  41
  42         WITH_HOST_BYTE_ORDER    The byte order of the host. Could
  43                                 be any of LITTLE_ENDIAN, BIG_ENDIAN
  44                                 or 0 (unknown).  Those macro's also
  45                                 need to be defined.
  46
  47         WITH_NTOH               Network byte order macros defined.
  48                                 Possible value is 32 or (maybe one
  49                                 day 64 because some 64bit network
  50                                 byte order macro is defined.
  51  */
  52
  53
  54 /* NetBSD:
  55
  56    NetBSD is easy, everything you could ever want is in a header file
  57    (well almost :-) */
  58
  59 #if defined(__NetBSD__)
  60 # include <machine/endian.h>
  61 # define WITH_NTOH 32 /* what about alpha? */
  62 # if (WITH_HOST_BYTE_ORDER == 0)
  63 #  undef WITH_HOST_BYTE_ORDER
  64 #  define WITH_HOST_BYTE_ORDER BYTE_ORDER
  65 # endif
  66 # if (BYTE_ORDER != WITH_HOST_BYTE_ORDER)
  67 #  error "host endian incorrectly configured, check config.h"
  68 # endif
  69 #endif
  70
  71 /* Linux is similarly easy.  */
  72
  73 #if defined(__linux__)
  74 # include <endian.h>
  75 # include <asm/byteorder.h>
  76 # if defined(__LITTLE_ENDIAN) && !defined(LITTLE_ENDIAN)
  77 #  define LITTLE_ENDIAN __LITTLE_ENDIAN
  78 # endif
  79 # if defined(__BIG_ENDIAN) && !defined(BIG_ENDIAN)
  80 #  define BIG_ENDIAN __BIG_ENDIAN
  81 # endif
  82 # if defined(__BYTE_ORDER) && !defined(BYTE_ORDER)
  83 #  define BYTE_ORDER __BYTE_ORDER
  84 # endif
  85 # if !defined(__alpha__)
  86 #  define WITH_NTOH 32 /* what about alpha? */
  87 # endif
  88 # if (WITH_HOST_BYTE_ORDER == 0)
  89 #  undef WITH_HOST_BYTE_ORDER
  90 #  define WITH_HOST_BYTE_ORDER BYTE_ORDER
  91 # endif
  92 # if (BYTE_ORDER != WITH_HOST_BYTE_ORDER)
  93 #  error "host endian incorrectly configured, check config.h"
  94 # endif
  95 #endif
  96
  97 /* INSERT HERE - hosts that have available LITTLE_ENDIAN and
  98    BIG_ENDIAN macro's */
  99
 100
 101 /* Some hosts don't define LITTLE_ENDIAN or BIG_ENDIAN, help them out */
 102
 103 #ifndef LITTLE_ENDIAN
 104 #define LITTLE_ENDIAN 1234
 105 #endif
 106 #ifndef BIG_ENDIAN
 107 #define BIG_ENDIAN 4321
 108 #endif
 109
 110
 111 /* SunOS on SPARC:
 112
 113    Big endian last time I looked */
 114
 115 #if defined(sparc) || defined(__sparc__)
 116 # if (WITH_HOST_BYTE_ORDER == 0)
 117 #  undef WITH_HOST_BYTE_ORDER
 118 #  define WITH_HOST_BYTE_ORDER BIG_ENDIAN
 119 # endif
 120 # if (WITH_HOST_BYTE_ORDER != BIG_ENDIAN)
 121 #  error "sun was big endian last time I looked ..."
 122 # endif
 123 #endif
 124
 125
 126 /* Random x86
 127
 128    Little endian last time I looked */
 129
 130 #if defined(i386) || defined(i486) || defined(i586) || defined(__i386__) || defined(__i486__) || defined(__i586__)
 131 # if (WITH_HOST_BYTE_ORDER == 0)
 132 #  undef WITH_HOST_BYTE_ORDER
 133 #  define WITH_HOST_BYTE_ORDER LITTLE_ENDIAN
 134 # endif
 135 # if (WITH_HOST_BYTE_ORDER != LITTLE_ENDIAN)
 136 #  error "x86 was little endian last time I looked ..."
 137 # endif
 138 #endif
 139
 140
 141 /* INSERT HERE - additional hosts that do not have LITTLE_ENDIAN and
 142    BIG_ENDIAN definitions available.  */
 143
 144
 145 /* SWAPPING:
 146
 147    According to the following table:
 148
 149                 TARG BE   TARG LE   TARG ??
 150        HOST BE    ok        s/w      s/w
 151        HOST LE   htohl      ok      ok|ntohl
 152        HOST ??   ntohl      s/w      s/w
 153
 154     define host <-> target byte order conversion macro's */
 155
 156
 157 /* IN PLACE:
 158
 159    These macro's given a variable argument swap its value in place if
 160    so required */
 161
 162 #define H2T(VARIABLE) \
 163 do { \
 164   switch (sizeof(VARIABLE)) { \
 165   case 1: VARIABLE = H2T_1(VARIABLE); break; \
 166   case 2: VARIABLE = H2T_2(VARIABLE); break; \
 167   case 4: VARIABLE = H2T_4(VARIABLE); break; \
 168   case 8: VARIABLE = H2T_8(VARIABLE); break; \
 169   } \
 170 } while (0)
 171
 172 #define T2H(VARIABLE) \
 173 do { \
 174   switch (sizeof(VARIABLE)) { \
 175   case 1: VARIABLE = T2H_1(VARIABLE); break; \
 176   case 2: VARIABLE = T2H_2(VARIABLE); break; \
 177   case 4: VARIABLE = T2H_4(VARIABLE); break; \
 178   case 8: VARIABLE = T2H_8(VARIABLE); break; \
 179   } \
 180 } while (0)
 181
 182
 183 /* TARGET WORD:
 184
 185    Byte swap a quantity the size of the targets word */
 186
 187 #if (WITH_TARGET_WORD_BITSIZE == 64)
 188 #define H2T_word(X) H2T_8(X)
 189 #define T2H_word(X) T2H_8(X)
 190 #endif
 191 #if (WITH_TARGET_WORD_BITSIZE == 32)
 192 #define H2T_word(X) H2T_4(X)
 193 #define T2H_word(X) T2H_4(X)
 194 #endif
 195
 196
 197 /* FUNCTIONS:
 198
 199    Returns the value swapped according to the host/target byte order */
 200
 201 /* no need to swap */
 202 #if (WITH_HOST_BYTE_ORDER \
 203      && WITH_TARGET_BYTE_ORDER \
 204      && WITH_HOST_BYTE_ORDER == WITH_TARGET_BYTE_ORDER )
 205 #define H2T_1(X) (X)
 206 #define H2T_2(X) (X)
 207 #define H2T_4(X) (X)
 208 #define H2T_8(X) (X)
 209 #define T2H_1(X) (X)
 210 #define T2H_2(X) (X)
 211 #define T2H_4(X) (X)
 212 #define T2H_8(X) (X)
 213 #endif
 214
 215 /* have ntoh and big endian target */
 216 #if (WITH_TARGET_BYTE_ORDER == BIG_ENDIAN \
 217      && WITH_HOST_BYTE_ORDER != BIG_ENDIAN \
 218      && WITH_NTOH)
 219 #define H2T_8(X) endian_h2t_8(X)
 220 #define H2T_4(X) htonl(X)
 221 #define H2T_2(X) htons(X)
 222 #define H2T_1(X) (X)
 223 #define T2H_8(X) endian_t2h_8(X)
 224 #define T2H_4(X) htonl(X)
 225 #define T2H_2(X) htons(X)
 226 #define T2H_1(X) (X)
 227 #endif
 228
 229 #if (defined (__i486__) || defined (__i586__)) && defined(__GNUC__) && WITH_BSWAP && WITH_NTOH
 230 #undef  htonl
 231 #undef  ntohl
 232 #define htonl(IN) __extension__ ({ int _out; __asm__ ("bswap %0" : "=r" (_out) : "0" (IN)); _out; })
 233 #define ntohl(IN) __extension__ ({ int _out; __asm__ ("bswap %0" : "=r" (_out) : "0" (IN)); _out; })
 234 #endif
 235
 236 /* have ntoh, little host and unknown target */
 237 #if (WITH_HOST_BYTE_ORDER == LITTLE_ENDIAN \
 238      && WITH_TARGET_BYTE_ORDER == 0 \
 239      && WITH_NTOH)
 240 #define H2T_8(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : endian_h2t_8(X))
 241 #define H2T_4(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : htonl(X))
 242 #define H2T_2(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : htons(X))
 243 #define H2T_1(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : (X))
 244 #define T2H_8(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : endian_t2h_8(X))
 245 #define T2H_4(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : htonl(X))
 246 #define T2H_2(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : htons(X))
 247 #define T2H_1(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER ? (X) : (X))
 248 #endif
 249
 250 /* if all else fails use software */
 251 #ifndef H2T_1
 252 #define H2T_1(X) (X)
 253 #define H2T_2(X) endian_h2t_2(X)
 254 #define H2T_4(X) endian_h2t_4(X)
 255 #define H2T_8(X) endian_h2t_8(X)
 256 #define T2H_1(X) (X)
 257 #define T2H_2(X) endian_t2h_2(X)
 258 #define T2H_4(X) endian_t2h_4(X)
 259 #define T2H_8(X) endian_t2h_8(X)
 260 #endif
 261
 262 #endif