gcc/hard-reg-set.h

   1 /* Sets (bit vectors) of hard registers, and operations on them.
   2    Copyright (C) 1987, 1992, 1994, 2000, 2003, 2004, 2005
   3    Free Software Foundation, Inc.
   4
   5 This file is part of GCC
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
  20 02110-1301, USA.  */
  21
  22 #ifndef GCC_HARD_REG_SET_H
  23 #define GCC_HARD_REG_SET_H
  24
  25 /* Define the type of a set of hard registers.  */
  26
  27 /* HARD_REG_ELT_TYPE is a typedef of the unsigned integral type which
  28    will be used for hard reg sets, either alone or in an array.
  29
  30    If HARD_REG_SET is a macro, its definition is HARD_REG_ELT_TYPE,
  31    and it has enough bits to represent all the target machine's hard
  32    registers.  Otherwise, it is a typedef for a suitably sized array
  33    of HARD_REG_ELT_TYPEs.  HARD_REG_SET_LONGS is defined as how many.
  34
  35    Note that lots of code assumes that the first part of a regset is
  36    the same format as a HARD_REG_SET.  To help make sure this is true,
  37    we only try the widest fast integer mode (HOST_WIDEST_FAST_INT)
  38    instead of all the smaller types.  This approach loses only if
  39    there are very few registers and then only in the few cases where
  40    we have an array of HARD_REG_SETs, so it needn't be as complex as
  41    it used to be.  */
  42
  43 typedef unsigned HOST_WIDEST_FAST_INT HARD_REG_ELT_TYPE;
  44
  45 #if FIRST_PSEUDO_REGISTER <= HOST_BITS_PER_WIDEST_FAST_INT
  46
  47 #define HARD_REG_SET HARD_REG_ELT_TYPE
  48
  49 #else
  50
  51 #define HARD_REG_SET_LONGS \
  52  ((FIRST_PSEUDO_REGISTER + HOST_BITS_PER_WIDEST_FAST_INT - 1)   \
  53   / HOST_BITS_PER_WIDEST_FAST_INT)
  54 typedef HARD_REG_ELT_TYPE HARD_REG_SET[HARD_REG_SET_LONGS];
  55
  56 #endif
  57
  58 /* HARD_CONST is used to cast a constant to the appropriate type
  59    for use with a HARD_REG_SET.  */
  60
  61 #define HARD_CONST(X) ((HARD_REG_ELT_TYPE) (X))
  62
  63 /* Define macros SET_HARD_REG_BIT, CLEAR_HARD_REG_BIT and TEST_HARD_REG_BIT
  64    to set, clear or test one bit in a hard reg set of type HARD_REG_SET.
  65    All three take two arguments: the set and the register number.
  66
  67    In the case where sets are arrays of longs, the first argument
  68    is actually a pointer to a long.
  69
  70    Define two macros for initializing a set:
  71    CLEAR_HARD_REG_SET and SET_HARD_REG_SET.
  72    These take just one argument.
  73
  74    Also define macros for copying hard reg sets:
  75    COPY_HARD_REG_SET and COMPL_HARD_REG_SET.
  76    These take two arguments TO and FROM; they read from FROM
  77    and store into TO.  COMPL_HARD_REG_SET complements each bit.
  78
  79    Also define macros for combining hard reg sets:
  80    IOR_HARD_REG_SET and AND_HARD_REG_SET.
  81    These take two arguments TO and FROM; they read from FROM
  82    and combine bitwise into TO.  Define also two variants
  83    IOR_COMPL_HARD_REG_SET and AND_COMPL_HARD_REG_SET
  84    which use the complement of the set FROM.
  85
  86    Also define GO_IF_HARD_REG_SUBSET (X, Y, TO):
  87    if X is a subset of Y, go to TO.
  88 */
  89
  90 #ifdef HARD_REG_SET
  91
  92 #define SET_HARD_REG_BIT(SET, BIT)  \
  93  ((SET) |= HARD_CONST (1) << (BIT))
  94 #define CLEAR_HARD_REG_BIT(SET, BIT)  \
  95  ((SET) &= ~(HARD_CONST (1) << (BIT)))
  96 #define TEST_HARD_REG_BIT(SET, BIT)  \
  97  (!!((SET) & (HARD_CONST (1) << (BIT))))
  98
  99 #define CLEAR_HARD_REG_SET(TO) ((TO) = HARD_CONST (0))
 100 #define SET_HARD_REG_SET(TO) ((TO) = ~ HARD_CONST (0))
 101
 102 #define COPY_HARD_REG_SET(TO, FROM) ((TO) = (FROM))
 103 #define COMPL_HARD_REG_SET(TO, FROM) ((TO) = ~(FROM))
 104
 105 #define IOR_HARD_REG_SET(TO, FROM) ((TO) |= (FROM))
 106 #define IOR_COMPL_HARD_REG_SET(TO, FROM) ((TO) |= ~ (FROM))
 107 #define AND_HARD_REG_SET(TO, FROM) ((TO) &= (FROM))
 108 #define AND_COMPL_HARD_REG_SET(TO, FROM) ((TO) &= ~ (FROM))
 109
 110 #define GO_IF_HARD_REG_SUBSET(X,Y,TO) if (HARD_CONST (0) == ((X) & ~(Y))) goto TO
 111
 112 #define GO_IF_HARD_REG_EQUAL(X,Y,TO) if ((X) == (Y)) goto TO
 113
 114 #else
 115
 116 #define UHOST_BITS_PER_WIDE_INT ((unsigned) HOST_BITS_PER_WIDEST_FAST_INT)
 117
 118 #define SET_HARD_REG_BIT(SET, BIT)              \
 119   ((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT]       \
 120    |= HARD_CONST (1) << ((BIT) % UHOST_BITS_PER_WIDE_INT))
 121
 122 #define CLEAR_HARD_REG_BIT(SET, BIT)            \
 123   ((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT]       \
 124    &= ~(HARD_CONST (1) << ((BIT) % UHOST_BITS_PER_WIDE_INT)))
 125
 126 #define TEST_HARD_REG_BIT(SET, BIT)             \
 127   (!!((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT]    \
 128       & (HARD_CONST (1) << ((BIT) % UHOST_BITS_PER_WIDE_INT))))
 129
 130 #if FIRST_PSEUDO_REGISTER <= 2*HOST_BITS_PER_WIDEST_FAST_INT
 131 #define CLEAR_HARD_REG_SET(TO)  \
 132 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);                        \
 133      scan_tp_[0] = 0;                                           \
 134      scan_tp_[1] = 0; } while (0)
 135
 136 #define SET_HARD_REG_SET(TO)  \
 137 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);                        \
 138      scan_tp_[0] = -1;                                          \
 139      scan_tp_[1] = -1; } while (0)
 140
 141 #define COPY_HARD_REG_SET(TO, FROM)  \
 142 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 143      scan_tp_[0] = scan_fp_[0];                                 \
 144      scan_tp_[1] = scan_fp_[1]; } while (0)
 145
 146 #define COMPL_HARD_REG_SET(TO, FROM)  \
 147 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 148      scan_tp_[0] = ~ scan_fp_[0];                               \
 149      scan_tp_[1] = ~ scan_fp_[1]; } while (0)
 150
 151 #define AND_HARD_REG_SET(TO, FROM)  \
 152 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 153      scan_tp_[0] &= scan_fp_[0];                                \
 154      scan_tp_[1] &= scan_fp_[1]; } while (0)
 155
 156 #define AND_COMPL_HARD_REG_SET(TO, FROM)  \
 157 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 158      scan_tp_[0] &= ~ scan_fp_[0];                              \
 159      scan_tp_[1] &= ~ scan_fp_[1]; } while (0)
 160
 161 #define IOR_HARD_REG_SET(TO, FROM)  \
 162 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 163      scan_tp_[0] |= scan_fp_[0];                                \
 164      scan_tp_[1] |= scan_fp_[1]; } while (0)
 165
 166 #define IOR_COMPL_HARD_REG_SET(TO, FROM)  \
 167 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 168      scan_tp_[0] |= ~ scan_fp_[0];                              \
 169      scan_tp_[1] |= ~ scan_fp_[1]; } while (0)
 170
 171 #define GO_IF_HARD_REG_SUBSET(X,Y,TO)  \
 172 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y);        \
 173      if ((0 == (scan_xp_[0] & ~ scan_yp_[0]))                   \
 174          && (0 == (scan_xp_[1] & ~ scan_yp_[1])))               \
 175         goto TO; } while (0)
 176
 177 #define GO_IF_HARD_REG_EQUAL(X,Y,TO)  \
 178 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y);        \
 179      if ((scan_xp_[0] == scan_yp_[0])                           \
 180          && (scan_xp_[1] == scan_yp_[1]))                       \
 181         goto TO; } while (0)
 182
 183 #else
 184 #if FIRST_PSEUDO_REGISTER <= 3*HOST_BITS_PER_WIDEST_FAST_INT
 185 #define CLEAR_HARD_REG_SET(TO)  \
 186 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);                        \
 187      scan_tp_[0] = 0;                                           \
 188      scan_tp_[1] = 0;                                           \
 189      scan_tp_[2] = 0; } while (0)
 190
 191 #define SET_HARD_REG_SET(TO)  \
 192 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);                        \
 193      scan_tp_[0] = -1;                                          \
 194      scan_tp_[1] = -1;                                          \
 195      scan_tp_[2] = -1; } while (0)
 196
 197 #define COPY_HARD_REG_SET(TO, FROM)  \
 198 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 199      scan_tp_[0] = scan_fp_[0];                                 \
 200      scan_tp_[1] = scan_fp_[1];                                 \
 201      scan_tp_[2] = scan_fp_[2]; } while (0)
 202
 203 #define COMPL_HARD_REG_SET(TO, FROM)  \
 204 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 205      scan_tp_[0] = ~ scan_fp_[0];                               \
 206      scan_tp_[1] = ~ scan_fp_[1];                               \
 207      scan_tp_[2] = ~ scan_fp_[2]; } while (0)
 208
 209 #define AND_HARD_REG_SET(TO, FROM)  \
 210 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 211      scan_tp_[0] &= scan_fp_[0];                                \
 212      scan_tp_[1] &= scan_fp_[1];                                \
 213      scan_tp_[2] &= scan_fp_[2]; } while (0)
 214
 215 #define AND_COMPL_HARD_REG_SET(TO, FROM)  \
 216 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 217      scan_tp_[0] &= ~ scan_fp_[0];                              \
 218      scan_tp_[1] &= ~ scan_fp_[1];                              \
 219      scan_tp_[2] &= ~ scan_fp_[2]; } while (0)
 220
 221 #define IOR_HARD_REG_SET(TO, FROM)  \
 222 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 223      scan_tp_[0] |= scan_fp_[0];                                \
 224      scan_tp_[1] |= scan_fp_[1];                                \
 225      scan_tp_[2] |= scan_fp_[2]; } while (0)
 226
 227 #define IOR_COMPL_HARD_REG_SET(TO, FROM)  \
 228 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 229      scan_tp_[0] |= ~ scan_fp_[0];                              \
 230      scan_tp_[1] |= ~ scan_fp_[1];                              \
 231      scan_tp_[2] |= ~ scan_fp_[2]; } while (0)
 232
 233 #define GO_IF_HARD_REG_SUBSET(X,Y,TO)  \
 234 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y);        \
 235      if ((0 == (scan_xp_[0] & ~ scan_yp_[0]))                   \
 236          && (0 == (scan_xp_[1] & ~ scan_yp_[1]))                \
 237          && (0 == (scan_xp_[2] & ~ scan_yp_[2])))               \
 238         goto TO; } while (0)
 239
 240 #define GO_IF_HARD_REG_EQUAL(X,Y,TO)  \
 241 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y);        \
 242      if ((scan_xp_[0] == scan_yp_[0])                           \
 243          && (scan_xp_[1] == scan_yp_[1])                        \
 244          && (scan_xp_[2] == scan_yp_[2]))                       \
 245         goto TO; } while (0)
 246
 247 #else
 248 #if FIRST_PSEUDO_REGISTER <= 4*HOST_BITS_PER_WIDEST_FAST_INT
 249 #define CLEAR_HARD_REG_SET(TO)  \
 250 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);                        \
 251      scan_tp_[0] = 0;                                           \
 252      scan_tp_[1] = 0;                                           \
 253      scan_tp_[2] = 0;                                           \
 254      scan_tp_[3] = 0; } while (0)
 255
 256 #define SET_HARD_REG_SET(TO)  \
 257 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);                        \
 258      scan_tp_[0] = -1;                                          \
 259      scan_tp_[1] = -1;                                          \
 260      scan_tp_[2] = -1;                                          \
 261      scan_tp_[3] = -1; } while (0)
 262
 263 #define COPY_HARD_REG_SET(TO, FROM)  \
 264 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 265      scan_tp_[0] = scan_fp_[0];                                 \
 266      scan_tp_[1] = scan_fp_[1];                                 \
 267      scan_tp_[2] = scan_fp_[2];                                 \
 268      scan_tp_[3] = scan_fp_[3]; } while (0)
 269
 270 #define COMPL_HARD_REG_SET(TO, FROM)  \
 271 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 272      scan_tp_[0] = ~ scan_fp_[0];                               \
 273      scan_tp_[1] = ~ scan_fp_[1];                               \
 274      scan_tp_[2] = ~ scan_fp_[2];                               \
 275      scan_tp_[3] = ~ scan_fp_[3]; } while (0)
 276
 277 #define AND_HARD_REG_SET(TO, FROM)  \
 278 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 279      scan_tp_[0] &= scan_fp_[0];                                \
 280      scan_tp_[1] &= scan_fp_[1];                                \
 281      scan_tp_[2] &= scan_fp_[2];                                \
 282      scan_tp_[3] &= scan_fp_[3]; } while (0)
 283
 284 #define AND_COMPL_HARD_REG_SET(TO, FROM)  \
 285 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 286      scan_tp_[0] &= ~ scan_fp_[0];                              \
 287      scan_tp_[1] &= ~ scan_fp_[1];                              \
 288      scan_tp_[2] &= ~ scan_fp_[2];                              \
 289      scan_tp_[3] &= ~ scan_fp_[3]; } while (0)
 290
 291 #define IOR_HARD_REG_SET(TO, FROM)  \
 292 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 293      scan_tp_[0] |= scan_fp_[0];                                \
 294      scan_tp_[1] |= scan_fp_[1];                                \
 295      scan_tp_[2] |= scan_fp_[2];                                \
 296      scan_tp_[3] |= scan_fp_[3]; } while (0)
 297
 298 #define IOR_COMPL_HARD_REG_SET(TO, FROM)  \
 299 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 300      scan_tp_[0] |= ~ scan_fp_[0];                              \
 301      scan_tp_[1] |= ~ scan_fp_[1];                              \
 302      scan_tp_[2] |= ~ scan_fp_[2];                              \
 303      scan_tp_[3] |= ~ scan_fp_[3]; } while (0)
 304
 305 #define GO_IF_HARD_REG_SUBSET(X,Y,TO)  \
 306 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y);        \
 307      if ((0 == (scan_xp_[0] & ~ scan_yp_[0]))                   \
 308          && (0 == (scan_xp_[1] & ~ scan_yp_[1]))                \
 309          && (0 == (scan_xp_[2] & ~ scan_yp_[2]))                \
 310          && (0 == (scan_xp_[3] & ~ scan_yp_[3])))               \
 311         goto TO; } while (0)
 312
 313 #define GO_IF_HARD_REG_EQUAL(X,Y,TO)  \
 314 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y);        \
 315      if ((scan_xp_[0] == scan_yp_[0])                           \
 316          && (scan_xp_[1] == scan_yp_[1])                        \
 317          && (scan_xp_[2] == scan_yp_[2])                        \
 318          && (scan_xp_[3] == scan_yp_[3]))                       \
 319         goto TO; } while (0)
 320
 321 #else /* FIRST_PSEUDO_REGISTER > 3*HOST_BITS_PER_WIDEST_FAST_INT */
 322
 323 #define CLEAR_HARD_REG_SET(TO)  \
 324 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);                        \
 325      int i;                                                     \
 326      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 327        *scan_tp_++ = 0; } while (0)
 328
 329 #define SET_HARD_REG_SET(TO)  \
 330 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO);                        \
 331      int i;                                                     \
 332      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 333        *scan_tp_++ = -1; } while (0)
 334
 335 #define COPY_HARD_REG_SET(TO, FROM)  \
 336 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 337      int i;                                                     \
 338      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 339        *scan_tp_++ = *scan_fp_++; } while (0)
 340
 341 #define COMPL_HARD_REG_SET(TO, FROM)  \
 342 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 343      int i;                                                     \
 344      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 345        *scan_tp_++ = ~ *scan_fp_++; } while (0)
 346
 347 #define AND_HARD_REG_SET(TO, FROM)  \
 348 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 349      int i;                                                     \
 350      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 351        *scan_tp_++ &= *scan_fp_++; } while (0)
 352
 353 #define AND_COMPL_HARD_REG_SET(TO, FROM)  \
 354 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 355      int i;                                                     \
 356      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 357        *scan_tp_++ &= ~ *scan_fp_++; } while (0)
 358
 359 #define IOR_HARD_REG_SET(TO, FROM)  \
 360 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 361      int i;                                                     \
 362      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 363        *scan_tp_++ |= *scan_fp_++; } while (0)
 364
 365 #define IOR_COMPL_HARD_REG_SET(TO, FROM)  \
 366 do { HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM);    \
 367      int i;                                                     \
 368      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 369        *scan_tp_++ |= ~ *scan_fp_++; } while (0)
 370
 371 #define GO_IF_HARD_REG_SUBSET(X,Y,TO)  \
 372 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y);        \
 373      int i;                                                     \
 374      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 375        if (0 != (*scan_xp_++ & ~ *scan_yp_++)) break;           \
 376      if (i == HARD_REG_SET_LONGS) goto TO; } while (0)
 377
 378 #define GO_IF_HARD_REG_EQUAL(X,Y,TO)  \
 379 do { HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y);        \
 380      int i;                                                     \
 381      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 382        if (*scan_xp_++ != *scan_yp_++) break;                   \
 383      if (i == HARD_REG_SET_LONGS) goto TO; } while (0)
 384
 385 #endif
 386 #endif
 387 #endif
 388 #endif
 389
 390 /* Define some standard sets of registers.  */
 391
 392 /* Indexed by hard register number, contains 1 for registers
 393    that are fixed use (stack pointer, pc, frame pointer, etc.).
 394    These are the registers that cannot be used to allocate
 395    a pseudo reg whose life does not cross calls.  */
 396
 397 extern char fixed_regs[FIRST_PSEUDO_REGISTER];
 398
 399 /* The same info as a HARD_REG_SET.  */
 400
 401 extern HARD_REG_SET fixed_reg_set;
 402
 403 /* Indexed by hard register number, contains 1 for registers
 404    that are fixed use or are clobbered by function calls.
 405    These are the registers that cannot be used to allocate
 406    a pseudo reg whose life crosses calls.  */
 407
 408 extern char call_used_regs[FIRST_PSEUDO_REGISTER];
 409
 410 #ifdef CALL_REALLY_USED_REGISTERS
 411 extern char call_really_used_regs[];
 412 #endif
 413
 414 /* The same info as a HARD_REG_SET.  */
 415
 416 extern HARD_REG_SET call_used_reg_set;
 417
 418 /* Registers that we don't want to caller save.  */
 419 extern HARD_REG_SET losing_caller_save_reg_set;
 420
 421 /* Indexed by hard register number, contains 1 for registers that are
 422    fixed use -- i.e. in fixed_regs -- or a function value return register
 423    or TARGET_STRUCT_VALUE_RTX or STATIC_CHAIN_REGNUM.  These are the
 424    registers that cannot hold quantities across calls even if we are
 425    willing to save and restore them.  */
 426
 427 extern char call_fixed_regs[FIRST_PSEUDO_REGISTER];
 428
 429 /* The same info as a HARD_REG_SET.  */
 430
 431 extern HARD_REG_SET call_fixed_reg_set;
 432
 433 /* Indexed by hard register number, contains 1 for registers
 434    that are being used for global register decls.
 435    These must be exempt from ordinary flow analysis
 436    and are also considered fixed.  */
 437
 438 extern char global_regs[FIRST_PSEUDO_REGISTER];
 439
 440 /* Contains 1 for registers that are set or clobbered by calls.  */
 441 /* ??? Ideally, this would be just call_used_regs plus global_regs, but
 442    for someone's bright idea to have call_used_regs strictly include
 443    fixed_regs.  Which leaves us guessing as to the set of fixed_regs
 444    that are actually preserved.  We know for sure that those associated
 445    with the local stack frame are safe, but scant others.  */
 446
 447 extern HARD_REG_SET regs_invalidated_by_call;
 448
 449 #ifdef REG_ALLOC_ORDER
 450 /* Table of register numbers in the order in which to try to use them.  */
 451
 452 extern int reg_alloc_order[FIRST_PSEUDO_REGISTER];
 453
 454 /* The inverse of reg_alloc_order.  */
 455
 456 extern int inv_reg_alloc_order[FIRST_PSEUDO_REGISTER];
 457 #endif
 458
 459 /* For each reg class, a HARD_REG_SET saying which registers are in it.  */
 460
 461 extern HARD_REG_SET reg_class_contents[N_REG_CLASSES];
 462
 463 /* For each reg class, number of regs it contains.  */
 464
 465 extern unsigned int reg_class_size[N_REG_CLASSES];
 466
 467 /* For each pair of reg classes,
 468    a largest reg class contained in their union.  */
 469
 470 extern enum reg_class reg_class_subunion[N_REG_CLASSES][N_REG_CLASSES];
 471
 472 /* For each pair of reg classes,
 473    the smallest reg class that contains their union.  */
 474
 475 extern enum reg_class reg_class_superunion[N_REG_CLASSES][N_REG_CLASSES];
 476
 477 /* Vector indexed by hardware reg giving its name.  */
 478
 479 extern const char * reg_names[FIRST_PSEUDO_REGISTER];
 480
 481 /* Vector indexed by reg class giving its name.  */
 482
 483 extern const char * reg_class_names[];
 484
 485 /* Given a hard REGN a FROM mode and a TO mode, return nonzero if
 486    REGN cannot change modes between the specified modes.  */
 487 #define REG_CANNOT_CHANGE_MODE_P(REGN, FROM, TO)                          \
 488          CANNOT_CHANGE_MODE_CLASS (FROM, TO, REGNO_REG_CLASS (REGN))
 489
 490 #endif /* ! GCC_HARD_REG_SET_H */