gcc/hard-reg-set.h

   1 /* Sets (bit vectors) of hard registers, and operations on them.
   2    Copyright (C) 1987, 1992, 1994 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC
   5
   6 GNU CC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU CC 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
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21
  22 /* Define the type of a set of hard registers.  */
  23
  24 /* HARD_REG_ELT_TYPE is a typedef of the unsigned integral type which
  25    will be used for hard reg sets, either alone or in an array.
  26
  27    If HARD_REG_SET is a macro, its definition is HARD_REG_ELT_TYPE,
  28    and it has enough bits to represent all the target machine's hard
  29    registers.  Otherwise, it is a typedef for a suitably sized array
  30    of HARD_REG_ELT_TYPEs.  HARD_REG_SET_LONGS is defined as how many.
  31
  32    Note that lots of code assumes that the first part of a regset is
  33    the same format as a HARD_REG_SET.  To help make sure this is true,
  34    we only try the widest integer mode (HOST_WIDE_INT) instead of all the
  35    smaller types.  This approach loses only if there are a very few
  36    registers and then only in the few cases where we have an array of
  37    HARD_REG_SETs, so it needn't be as complex as it used to be.  */
  38
  39 typedef unsigned HOST_WIDE_INT HARD_REG_ELT_TYPE;
  40
  41 #if FIRST_PSEUDO_REGISTER <= HOST_BITS_PER_WIDE_INT
  42
  43 #define HARD_REG_SET HARD_REG_ELT_TYPE
  44
  45 #else
  46
  47 #define HARD_REG_SET_LONGS \
  48  ((FIRST_PSEUDO_REGISTER + HOST_BITS_PER_WIDE_INT - 1)  \
  49   / HOST_BITS_PER_WIDE_INT)
  50 typedef HARD_REG_ELT_TYPE HARD_REG_SET[HARD_REG_SET_LONGS];
  51
  52 #endif
  53
  54 /* HARD_CONST is used to cast a constant to the appropriate type
  55    for use with a HARD_REG_SET.  */
  56
  57 #define HARD_CONST(X) ((HARD_REG_ELT_TYPE) (X))
  58
  59 /* Define macros SET_HARD_REG_BIT, CLEAR_HARD_REG_BIT and TEST_HARD_REG_BIT
  60    to set, clear or test one bit in a hard reg set of type HARD_REG_SET.
  61    All three take two arguments: the set and the register number.
  62
  63    In the case where sets are arrays of longs, the first argument
  64    is actually a pointer to a long.
  65
  66    Define two macros for initializing a set:
  67    CLEAR_HARD_REG_SET and SET_HARD_REG_SET.
  68    These take just one argument.
  69
  70    Also define macros for copying hard reg sets:
  71    COPY_HARD_REG_SET and COMPL_HARD_REG_SET.
  72    These take two arguments TO and FROM; they read from FROM
  73    and store into TO.  COMPL_HARD_REG_SET complements each bit.
  74
  75    Also define macros for combining hard reg sets:
  76    IOR_HARD_REG_SET and AND_HARD_REG_SET.
  77    These take two arguments TO and FROM; they read from FROM
  78    and combine bitwise into TO.  Define also two variants
  79    IOR_COMPL_HARD_REG_SET and AND_COMPL_HARD_REG_SET
  80    which use the complement of the set FROM.
  81
  82    Also define GO_IF_HARD_REG_SUBSET (X, Y, TO):
  83    if X is a subset of Y, go to TO.
  84 */
  85
  86 #ifdef HARD_REG_SET
  87
  88 #define SET_HARD_REG_BIT(SET, BIT)  \
  89  ((SET) |= HARD_CONST (1) << (BIT))
  90 #define CLEAR_HARD_REG_BIT(SET, BIT)  \
  91  ((SET) &= ~(HARD_CONST (1) << (BIT)))
  92 #define TEST_HARD_REG_BIT(SET, BIT)  \
  93  ((SET) & (HARD_CONST (1) << (BIT)))
  94
  95 #define CLEAR_HARD_REG_SET(TO) ((TO) = HARD_CONST (0))
  96 #define SET_HARD_REG_SET(TO) ((TO) = ~ HARD_CONST (0))
  97
  98 #define COPY_HARD_REG_SET(TO, FROM) ((TO) = (FROM))
  99 #define COMPL_HARD_REG_SET(TO, FROM) ((TO) = ~(FROM))
 100
 101 #define IOR_HARD_REG_SET(TO, FROM) ((TO) |= (FROM))
 102 #define IOR_COMPL_HARD_REG_SET(TO, FROM) ((TO) |= ~ (FROM))
 103 #define AND_HARD_REG_SET(TO, FROM) ((TO) &= (FROM))
 104 #define AND_COMPL_HARD_REG_SET(TO, FROM) ((TO) &= ~ (FROM))
 105
 106 #define GO_IF_HARD_REG_SUBSET(X,Y,TO) if (HARD_CONST (0) == ((X) & ~(Y))) goto TO
 107
 108 #define GO_IF_HARD_REG_EQUAL(X,Y,TO) if ((X) == (Y)) goto TO
 109
 110 #else
 111
 112 #define UHOST_BITS_PER_WIDE_INT ((unsigned) HOST_BITS_PER_WIDE_INT)
 113
 114 #define SET_HARD_REG_BIT(SET, BIT)              \
 115   ((SET)[(BIT) / UHOST_BITS_PER_WIDE_INT]       \
 116    |= HARD_CONST (1) << ((BIT) % UHOST_BITS_PER_WIDE_INT))
 117
 118 #define CLEAR_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 TEST_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 CLEAR_HARD_REG_SET(TO)  \
 127 do { register HARD_REG_ELT_TYPE *scan_tp_ = (TO);               \
 128      register int i;                                            \
 129      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 130        *scan_tp_++ = 0; } while (0)
 131
 132 #define SET_HARD_REG_SET(TO)  \
 133 do { register HARD_REG_ELT_TYPE *scan_tp_ = (TO);               \
 134      register int i;                                            \
 135      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 136        *scan_tp_++ = -1; } while (0)
 137
 138 #define COPY_HARD_REG_SET(TO, FROM)  \
 139 do { register HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
 140      register int i;                                            \
 141      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 142        *scan_tp_++ = *scan_fp_++; } while (0)
 143
 144 #define COMPL_HARD_REG_SET(TO, FROM)  \
 145 do { register HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
 146      register int i;                                            \
 147      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 148        *scan_tp_++ = ~ *scan_fp_++; } while (0)
 149
 150 #define AND_HARD_REG_SET(TO, FROM)  \
 151 do { register HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
 152      register int i;                                            \
 153      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 154        *scan_tp_++ &= *scan_fp_++; } while (0)
 155
 156 #define AND_COMPL_HARD_REG_SET(TO, FROM)  \
 157 do { register HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
 158      register int i;                                            \
 159      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 160        *scan_tp_++ &= ~ *scan_fp_++; } while (0)
 161
 162 #define IOR_HARD_REG_SET(TO, FROM)  \
 163 do { register HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
 164      register int i;                                            \
 165      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 166        *scan_tp_++ |= *scan_fp_++; } while (0)
 167
 168 #define IOR_COMPL_HARD_REG_SET(TO, FROM)  \
 169 do { register HARD_REG_ELT_TYPE *scan_tp_ = (TO), *scan_fp_ = (FROM); \
 170      register int i;                                            \
 171      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 172        *scan_tp_++ |= ~ *scan_fp_++; } while (0)
 173
 174 #define GO_IF_HARD_REG_SUBSET(X,Y,TO)  \
 175 do { register HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y); \
 176      register int i;                                            \
 177      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 178        if (0 != (*scan_xp_++ & ~ *scan_yp_++)) break;           \
 179      if (i == HARD_REG_SET_LONGS) goto TO; } while (0)
 180
 181 #define GO_IF_HARD_REG_EQUAL(X,Y,TO)  \
 182 do { register HARD_REG_ELT_TYPE *scan_xp_ = (X), *scan_yp_ = (Y); \
 183      register int i;                                            \
 184      for (i = 0; i < HARD_REG_SET_LONGS; i++)                   \
 185        if (*scan_xp_++ != *scan_yp_++) break;                   \
 186      if (i == HARD_REG_SET_LONGS) goto TO; } while (0)
 187
 188 #endif
 189
 190 /* Define some standard sets of registers.  */
 191
 192 /* Indexed by hard register number, contains 1 for registers
 193    that are fixed use (stack pointer, pc, frame pointer, etc.).
 194    These are the registers that cannot be used to allocate
 195    a pseudo reg whose life does not cross calls.  */
 196
 197 extern char fixed_regs[FIRST_PSEUDO_REGISTER];
 198
 199 /* The same info as a HARD_REG_SET.  */
 200
 201 extern HARD_REG_SET fixed_reg_set;
 202
 203 /* Indexed by hard register number, contains 1 for registers
 204    that are fixed use or are clobbered by function calls.
 205    These are the registers that cannot be used to allocate
 206    a pseudo reg whose life crosses calls.  */
 207
 208 extern char call_used_regs[FIRST_PSEUDO_REGISTER];
 209
 210 /* The same info as a HARD_REG_SET.  */
 211
 212 extern HARD_REG_SET call_used_reg_set;
 213
 214 /* Registers that we don't want to caller save.  */
 215 extern HARD_REG_SET losing_caller_save_reg_set;
 216
 217 /* Indexed by hard register number, contains 1 for registers that are
 218    fixed use -- i.e. in fixed_regs -- or a function value return register
 219    or STRUCT_VALUE_REGNUM or STATIC_CHAIN_REGNUM.  These are the
 220    registers that cannot hold quantities across calls even if we are
 221    willing to save and restore them.  */
 222
 223 extern char call_fixed_regs[FIRST_PSEUDO_REGISTER];
 224
 225 /* The same info as a HARD_REG_SET.  */
 226
 227 extern HARD_REG_SET call_fixed_reg_set;
 228
 229 /* Indexed by hard register number, contains 1 for registers
 230    that are being used for global register decls.
 231    These must be exempt from ordinary flow analysis
 232    and are also considered fixed.  */
 233
 234 extern char global_regs[FIRST_PSEUDO_REGISTER];
 235
 236 /* Table of register numbers in the order in which to try to use them.  */
 237
 238 #ifdef REG_ALLOC_ORDER   /* Avoid undef symbol in certain broken linkers.  */
 239 extern int reg_alloc_order[FIRST_PSEUDO_REGISTER];
 240 #endif
 241
 242 /* For each reg class, a HARD_REG_SET saying which registers are in it.  */
 243
 244 extern HARD_REG_SET reg_class_contents[];
 245
 246 /* For each reg class, number of regs it contains.  */
 247
 248 extern int reg_class_size[N_REG_CLASSES];
 249
 250 /* For each reg class, table listing all the containing classes.  */
 251
 252 extern enum reg_class reg_class_superclasses[N_REG_CLASSES][N_REG_CLASSES];
 253
 254 /* For each reg class, table listing all the classes contained in it.  */
 255
 256 extern enum reg_class reg_class_subclasses[N_REG_CLASSES][N_REG_CLASSES];
 257
 258 /* For each pair of reg classes,
 259    a largest reg class contained in their union.  */
 260
 261 extern enum reg_class reg_class_subunion[N_REG_CLASSES][N_REG_CLASSES];
 262
 263 /* For each pair of reg classes,
 264    the smallest reg class that contains their union.  */
 265
 266 extern enum reg_class reg_class_superunion[N_REG_CLASSES][N_REG_CLASSES];
 267
 268 /* Number of non-fixed registers.  */
 269
 270 extern int n_non_fixed_regs;
 271
 272 /* Vector indexed by hardware reg giving its name.  */
 273
 274 extern char *reg_names[FIRST_PSEUDO_REGISTER];