sim/ppc/sim-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 _SIM_ENDIAN_H_
  23 #define _SIM_ENDIAN_H_
  24
  25 #ifndef INLINE_SIM_ENDIAN
  26 #define INLINE_SIM_ENDIAN
  27 #endif
  28
  29
  30 /* C byte conversion functions */
  31
  32 INLINE_SIM_ENDIAN unsigned_1 endian_h2t_1(unsigned_1 x);
  33 INLINE_SIM_ENDIAN unsigned_2 endian_h2t_2(unsigned_2 x);
  34 INLINE_SIM_ENDIAN unsigned_4 endian_h2t_4(unsigned_4 x);
  35 INLINE_SIM_ENDIAN unsigned_8 endian_h2t_8(unsigned_8 x);
  36
  37 INLINE_SIM_ENDIAN unsigned_1 endian_t2h_1(unsigned_1 x);
  38 INLINE_SIM_ENDIAN unsigned_2 endian_t2h_2(unsigned_2 x);
  39 INLINE_SIM_ENDIAN unsigned_4 endian_t2h_4(unsigned_4 x);
  40 INLINE_SIM_ENDIAN unsigned_8 endian_t2h_8(unsigned_8 x);
  41
  42 INLINE_SIM_ENDIAN unsigned_1 swap_1(unsigned_1 x);
  43 INLINE_SIM_ENDIAN unsigned_2 swap_2(unsigned_2 x);
  44 INLINE_SIM_ENDIAN unsigned_4 swap_4(unsigned_4 x);
  45 INLINE_SIM_ENDIAN unsigned_8 swap_8(unsigned_8 x);
  46
  47
  48 /* Host dependant:
  49
  50    The CPP below defines information about the compilation host.  In
  51    particular it defines the macro's:
  52
  53         WITH_HOST_BYTE_ORDER    The byte order of the host. Could
  54                                 be any of LITTLE_ENDIAN, BIG_ENDIAN
  55                                 or 0 (unknown).  Those macro's also
  56                                 need to be defined.
  57
  58         WITH_NTOH               Network byte order macros defined.
  59                                 Possible value is 32 or (maybe one
  60                                 day 64 because some 64bit network
  61                                 byte order macro is defined.
  62  */
  63
  64
  65 /* NetBSD:
  66
  67    NetBSD is easy, everything you could ever want is in a header file
  68    (well almost :-) */
  69
  70 #if defined(__NetBSD__)
  71 # include <machine/endian.h>
  72 # define WITH_NTOH 32 /* what about alpha? */
  73 # if (WITH_HOST_BYTE_ORDER == 0)
  74 #  undef WITH_HOST_BYTE_ORDER
  75 #  define WITH_HOST_BYTE_ORDER BYTE_ORDER
  76 # endif
  77 # if (BYTE_ORDER != WITH_HOST_BYTE_ORDER)
  78 #  error "host endian incorrectly configured, check config.h"
  79 # endif
  80 #endif
  81
  82 /* Linux is similarly easy.  */
  83
  84 #if defined(__linux__)
  85 # include <endian.h>
  86 # include <asm/byteorder.h>
  87 # if defined(__LITTLE_ENDIAN) && !defined(LITTLE_ENDIAN)
  88 #  define LITTLE_ENDIAN __LITTLE_ENDIAN
  89 # endif
  90 # if defined(__BIG_ENDIAN) && !defined(BIG_ENDIAN)
  91 #  define BIG_ENDIAN __BIG_ENDIAN
  92 # endif
  93 # if defined(__BYTE_ORDER) && !defined(BYTE_ORDER)
  94 #  define BYTE_ORDER __BYTE_ORDER
  95 # endif
  96 # if !defined(__alpha__)
  97 #  define WITH_NTOH 32 /* what about alpha? */
  98 # endif
  99 # if (WITH_HOST_BYTE_ORDER == 0)
 100 #  undef WITH_HOST_BYTE_ORDER
 101 #  define WITH_HOST_BYTE_ORDER BYTE_ORDER
 102 # endif
 103 # if (BYTE_ORDER != WITH_HOST_BYTE_ORDER)
 104 #  error "host endian incorrectly configured, check config.h"
 105 # endif
 106 #endif
 107
 108 /* INSERT HERE - hosts that have available LITTLE_ENDIAN and
 109    BIG_ENDIAN macro's */
 110
 111
 112 /* Some hosts don't define LITTLE_ENDIAN or BIG_ENDIAN, help them out */
 113
 114 #ifndef LITTLE_ENDIAN
 115 #define LITTLE_ENDIAN 1234
 116 #endif
 117 #ifndef BIG_ENDIAN
 118 #define BIG_ENDIAN 4321
 119 #endif
 120
 121
 122 /* SunOS on SPARC:
 123
 124    Big endian last time I looked */
 125
 126 #if defined(sparc) || defined(__sparc__)
 127 # if (WITH_HOST_BYTE_ORDER == 0)
 128 #  undef WITH_HOST_BYTE_ORDER
 129 #  define WITH_HOST_BYTE_ORDER BIG_ENDIAN
 130 # endif
 131 # if (WITH_HOST_BYTE_ORDER != BIG_ENDIAN)
 132 #  error "sun was big endian last time I looked ..."
 133 # endif
 134 #endif
 135
 136
 137 /* Random x86
 138
 139    Little endian last time I looked */
 140
 141 #if defined(i386) || defined(i486) || defined(i586) || defined(__i386__) || defined(__i486__) || defined(__i586__)
 142 # if (WITH_HOST_BYTE_ORDER == 0)
 143 #  undef WITH_HOST_BYTE_ORDER
 144 #  define WITH_HOST_BYTE_ORDER LITTLE_ENDIAN
 145 # endif
 146 # if (WITH_HOST_BYTE_ORDER != LITTLE_ENDIAN)
 147 #  error "x86 was little endian last time I looked ..."
 148 # endif
 149 #endif
 150
 151 #if (defined (__i486__) || defined (__i586__)) && defined(__GNUC__) && WITH_BSWAP && WITH_NTOH
 152 #undef  htonl
 153 #undef  ntohl
 154 #define htonl(IN) __extension__ ({ int _out; __asm__ ("bswap %0" : "=r" (_out) : "0" (IN)); _out; })
 155 #define ntohl(IN) __extension__ ({ int _out; __asm__ ("bswap %0" : "=r" (_out) : "0" (IN)); _out; })
 156 #endif
 157
 158
 159 /* Configure defines WORDS_BIGENDIAN if the host is big endian.  */
 160
 161 #if (WITH_HOST_BYTE_ORDER == 0)
 162 # undef WITH_HOST_BYTE_ORDER
 163 # ifdef WORDS_BIGENDIAN
 164 #  define WITH_HOST_BYTE_ORDER BIG_ENDIAN
 165 # else
 166 #  define WITH_HOST_BYTE_ORDER LITTLE_ENDIAN
 167 # endif
 168 #endif
 169
 170 /* SWAP:
 171
 172    Some times a swap must always be performed, select the most
 173    effecient method to swap a collection of bytes.
 174
 175    HOST BE        sw
 176    HOST LE      sw/ntoh
 177    HOST ??        sw
 178
 179    */
 180
 181 #if (WITH_HOST_BYTE_ORDER \
 182      && WITH_NTOH \
 183      && WITH_HOST_BYTE_ORDER == LITTLE_ENDIAN)
 184 #define SWAP_1(X) (X)
 185 #define SWAP_2(X) ntohs(X)
 186 #define SWAP_4(X) ntohl(X)
 187 #define SWAP_8(X) swap_8(X)
 188 #else
 189 #define SWAP_1(X) (X)
 190 #define SWAP_2(X) swap_2(X)
 191 #define SWAP_4(X) swap_4(X)
 192 #define SWAP_8(X) swap_8(X)
 193 #endif
 194
 195
 196 /* CONVERSION:
 197
 198    Convert between host and target byte orders by the most efficient
 199    method known (if needed at all)
 200
 201                 TARG BE   TARG LE   TARG ??
 202        HOST BE    ok       swap      swap
 203        HOST LE   htohl      ok      ok|ntohl
 204        HOST ??   ntohl     swap      swap
 205
 206    */
 207
 208
 209 /* FUNCTIONS:
 210
 211    Returns the value swapped according to the host/target byte order */
 212
 213 /* no need to swap */
 214 #if (WITH_HOST_BYTE_ORDER \
 215      && WITH_TARGET_BYTE_ORDER \
 216      && WITH_HOST_BYTE_ORDER == WITH_TARGET_BYTE_ORDER )
 217 #define H2T_1(X) (X)
 218 #define H2T_2(X) (X)
 219 #define H2T_4(X) (X)
 220 #define H2T_8(X) (X)
 221 #define T2H_1(X) (X)
 222 #define T2H_2(X) (X)
 223 #define T2H_4(X) (X)
 224 #define T2H_8(X) (X)
 225 #endif
 226
 227 /* have ntoh and big endian target */
 228 #if (WITH_TARGET_BYTE_ORDER == BIG_ENDIAN \
 229      && WITH_HOST_BYTE_ORDER != BIG_ENDIAN \
 230      && WITH_NTOH)
 231 #define H2T_8(X) endian_h2t_8(X)
 232 #define H2T_4(X) htonl(X)
 233 #define H2T_2(X) htons(X)
 234 #define H2T_1(X) (X)
 235 #define T2H_8(X) endian_t2h_8(X)
 236 #define T2H_4(X) htonl(X)
 237 #define T2H_2(X) htons(X)
 238 #define T2H_1(X) (X)
 239 #endif
 240
 241 /* have ntoh, little host and unknown target */
 242 #if (WITH_HOST_BYTE_ORDER == LITTLE_ENDIAN \
 243      && WITH_TARGET_BYTE_ORDER == 0 \
 244      && WITH_NTOH)
 245 #define H2T_8(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER \
 246                   ? (X) : endian_h2t_8(X))
 247 #define H2T_4(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER \
 248                   ? (X) : htonl(X))
 249 #define H2T_2(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER \
 250                   ? (X) : htons(X))
 251 #define H2T_1(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER \
 252                   ? (X) : (X))
 253 #define T2H_8(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER \
 254                   ? (X) : endian_t2h_8(X))
 255 #define T2H_4(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER \
 256                   ? (X) : htonl(X))
 257 #define T2H_2(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER \
 258                   ? (X) : htons(X))
 259 #define T2H_1(X) (CURRENT_TARGET_BYTE_ORDER == CURRENT_HOST_BYTE_ORDER \
 260                   ? (X) : (X))
 261 #endif
 262
 263 /* if all else fails use software */
 264 #ifndef H2T_1
 265 #define H2T_1(X) (X)
 266 #define H2T_2(X) endian_h2t_2(X)
 267 #define H2T_4(X) endian_h2t_4(X)
 268 #define H2T_8(X) endian_h2t_8(X)
 269 #define T2H_1(X) (X)
 270 #define T2H_2(X) endian_t2h_2(X)
 271 #define T2H_4(X) endian_t2h_4(X)
 272 #define T2H_8(X) endian_t2h_8(X)
 273 #endif
 274
 275
 276 /* CONVERT IN PLACE:
 277
 278    These macros, given an argument of unknown size, swap its value in
 279    place if a host/target conversion is required. */
 280
 281 #define H2T(VARIABLE) \
 282 do { \
 283   switch (sizeof(VARIABLE)) { \
 284   case 1: VARIABLE = H2T_1(VARIABLE); break; \
 285   case 2: VARIABLE = H2T_2(VARIABLE); break; \
 286   case 4: VARIABLE = H2T_4(VARIABLE); break; \
 287   case 8: VARIABLE = H2T_8(VARIABLE); break; \
 288   } \
 289 } while (0)
 290
 291 #define T2H(VARIABLE) \
 292 do { \
 293   switch (sizeof(VARIABLE)) { \
 294   case 1: VARIABLE = T2H_1(VARIABLE); break; \
 295   case 2: VARIABLE = T2H_2(VARIABLE); break; \
 296   case 4: VARIABLE = T2H_4(VARIABLE); break; \
 297   case 8: VARIABLE = T2H_8(VARIABLE); break; \
 298   } \
 299 } while (0)
 300
 301
 302 /* TARGET WORD:
 303
 304    Byte swap a quantity the size of the targets word */
 305
 306 #if (WITH_TARGET_WORD_BITSIZE == 64)
 307 #define H2T_word(X) H2T_8(X)
 308 #define T2H_word(X) T2H_8(X)
 309 #endif
 310 #if (WITH_TARGET_WORD_BITSIZE == 32)
 311 #define H2T_word(X) H2T_4(X)
 312 #define T2H_word(X) T2H_4(X)
 313 #endif
 314
 315 #endif /* _SIM_ENDIAN_H_ */