gcc/recog.h

   1 /* Declarations for interface to insn recognizer and insn-output.c.
   2    Copyright (C) 1987, 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004
   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, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.  */
  21
  22 /* Random number that should be large enough for all purposes.  */
  23 #define MAX_RECOG_ALTERNATIVES 30
  24
  25 /* Types of operands.  */
  26 enum op_type {
  27   OP_IN,
  28   OP_OUT,
  29   OP_INOUT
  30 };
  31
  32 struct operand_alternative
  33 {
  34   /* Pointer to the beginning of the constraint string for this alternative,
  35      for easier access by alternative number.  */
  36   const char *constraint;
  37
  38   /* The register class valid for this alternative (possibly NO_REGS).  */
  39   enum reg_class cl;
  40
  41   /* "Badness" of this alternative, computed from number of '?' and '!'
  42      characters in the constraint string.  */
  43   unsigned int reject;
  44
  45   /* -1 if no matching constraint was found, or an operand number.  */
  46   int matches;
  47   /* The same information, but reversed: -1 if this operand is not
  48      matched by any other, or the operand number of the operand that
  49      matches this one.  */
  50   int matched;
  51
  52   /* Nonzero if '&' was found in the constraint string.  */
  53   unsigned int earlyclobber:1;
  54   /* Nonzero if 'm' was found in the constraint string.  */
  55   unsigned int memory_ok:1;
  56   /* Nonzero if 'o' was found in the constraint string.  */
  57   unsigned int offmem_ok:1;
  58   /* Nonzero if 'V' was found in the constraint string.  */
  59   unsigned int nonoffmem_ok:1;
  60   /* Nonzero if '<' was found in the constraint string.  */
  61   unsigned int decmem_ok:1;
  62   /* Nonzero if '>' was found in the constraint string.  */
  63   unsigned int incmem_ok:1;
  64   /* Nonzero if 'p' was found in the constraint string.  */
  65   unsigned int is_address:1;
  66   /* Nonzero if 'X' was found in the constraint string, or if the constraint
  67      string for this alternative was empty.  */
  68   unsigned int anything_ok:1;
  69 };
  70
  71
  72 extern void init_recog (void);
  73 extern void init_recog_no_volatile (void);
  74 extern int check_asm_operands (rtx);
  75 extern int asm_operand_ok (rtx, const char *);
  76 extern int validate_change (rtx, rtx *, rtx, int);
  77 extern int insn_invalid_p (rtx);
  78 extern int apply_change_group (void);
  79 extern int num_validated_changes (void);
  80 extern void cancel_changes (int);
  81 extern int constrain_operands (int);
  82 extern int constrain_operands_cached (int);
  83 extern int memory_address_p (enum machine_mode, rtx);
  84 extern int strict_memory_address_p (enum machine_mode, rtx);
  85 extern int validate_replace_rtx_subexp (rtx, rtx, rtx, rtx *);
  86 extern int validate_replace_rtx (rtx, rtx, rtx);
  87 extern void validate_replace_rtx_group (rtx, rtx, rtx);
  88 extern void validate_replace_src_group (rtx, rtx, rtx);
  89 extern int num_changes_pending (void);
  90 #ifdef HAVE_cc0
  91 extern int next_insn_tests_no_inequality (rtx);
  92 #endif
  93 extern int reg_fits_class_p (rtx, enum reg_class, int, enum machine_mode);
  94 extern rtx *find_single_use (rtx, rtx, rtx *);
  95
  96 extern int offsettable_memref_p (rtx);
  97 extern int offsettable_nonstrict_memref_p (rtx);
  98 extern int offsettable_address_p (int, enum machine_mode, rtx);
  99 extern int mode_dependent_address_p (rtx);
 100
 101 extern int recog (rtx, rtx, int *);
 102 static inline int recog_memoized (rtx insn);
 103 extern void add_clobbers (rtx, int);
 104 extern int added_clobbers_hard_reg_p (int);
 105 extern void insn_extract (rtx);
 106 extern void extract_insn (rtx);
 107 extern void extract_constrain_insn_cached (rtx);
 108 extern void extract_insn_cached (rtx);
 109 extern void preprocess_constraints (void);
 110 extern rtx peep2_next_insn (int);
 111 extern int peep2_regno_dead_p (int, int);
 112 extern int peep2_reg_dead_p (int, rtx);
 113 #ifdef CLEAR_HARD_REG_SET
 114 extern rtx peep2_find_free_register (int, int, const char *,
 115                                      enum machine_mode, HARD_REG_SET *);
 116 #endif
 117 extern void peephole2_optimize (FILE *);
 118 extern rtx peephole2_insns (rtx, rtx, int *);
 119
 120 extern int store_data_bypass_p (rtx, rtx);
 121 extern int if_test_bypass_p (rtx, rtx);
 122
 123 /* Try recognizing the instruction INSN,
 124    and return the code number that results.
 125    Remember the code so that repeated calls do not
 126    need to spend the time for actual rerecognition.
 127
 128    This function is the normal interface to instruction recognition.
 129    The automatically-generated function `recog' is normally called
 130    through this one.  (The only exception is in combine.c.)  */
 131
 132 static inline int
 133 recog_memoized (rtx insn)
 134 {
 135   if (INSN_CODE (insn) < 0)
 136     INSN_CODE (insn) = recog (PATTERN (insn), insn, 0);
 137   return INSN_CODE (insn);
 138 }
 139
 140 /* Nonzero means volatile operands are recognized.  */
 141 extern int volatile_ok;
 142
 143 /* Set by constrain_operands to the number of the alternative that
 144    matched.  */
 145 extern int which_alternative;
 146
 147 /* The following vectors hold the results from insn_extract.  */
 148
 149 struct recog_data
 150 {
 151   /* It is very tempting to make the 5 operand related arrays into a
 152      structure and index on that.  However, to be source compatible
 153      with all of the existing md file insn constraints and output
 154      templates, we need `operand' as a flat array.  Without that
 155      member, making an array for the rest seems pointless.  */
 156
 157   /* Gives value of operand N.  */
 158   rtx operand[MAX_RECOG_OPERANDS];
 159
 160   /* Gives location where operand N was found.  */
 161   rtx *operand_loc[MAX_RECOG_OPERANDS];
 162
 163   /* Gives the constraint string for operand N.  */
 164   const char *constraints[MAX_RECOG_OPERANDS];
 165
 166   /* Gives the mode of operand N.  */
 167   enum machine_mode operand_mode[MAX_RECOG_OPERANDS];
 168
 169   /* Gives the type (in, out, inout) for operand N.  */
 170   enum op_type operand_type[MAX_RECOG_OPERANDS];
 171
 172   /* Gives location where the Nth duplicate-appearance of an operand
 173      was found.  This is something that matched MATCH_DUP.  */
 174   rtx *dup_loc[MAX_DUP_OPERANDS];
 175
 176   /* Gives the operand number that was duplicated in the Nth
 177      duplicate-appearance of an operand.  */
 178   char dup_num[MAX_DUP_OPERANDS];
 179
 180   /* ??? Note that these are `char' instead of `unsigned char' to (try to)
 181      avoid certain lossage from K&R C, wherein `unsigned char' default
 182      promotes to `unsigned int' instead of `int' as in ISO C.  As of 1999,
 183      the most common places to bootstrap from K&R C are SunOS and HPUX,
 184      both of which have signed characters by default.  The only other
 185      supported natives that have both K&R C and unsigned characters are
 186      ROMP and Irix 3, and neither have been seen for a while, but do
 187      continue to consider unsignedness when performing arithmetic inside
 188      a comparison.  */
 189
 190   /* The number of operands of the insn.  */
 191   char n_operands;
 192
 193   /* The number of MATCH_DUPs in the insn.  */
 194   char n_dups;
 195
 196   /* The number of alternatives in the constraints for the insn.  */
 197   char n_alternatives;
 198
 199   /* In case we are caching, hold insn data was generated for.  */
 200   rtx insn;
 201 };
 202
 203 extern struct recog_data recog_data;
 204
 205 /* Contains a vector of operand_alternative structures for every operand.
 206    Set up by preprocess_constraints.  */
 207 extern struct operand_alternative recog_op_alt[MAX_RECOG_OPERANDS][MAX_RECOG_ALTERNATIVES];
 208
 209 /* A table defined in insn-output.c that give information about
 210    each insn-code value.  */
 211
 212 typedef int (*insn_operand_predicate_fn) (rtx, enum machine_mode);
 213 typedef const char * (*insn_output_fn) (rtx *, rtx);
 214 typedef rtx (*insn_gen_fn) (rtx, ...);
 215
 216 struct insn_operand_data
 217 {
 218   const insn_operand_predicate_fn predicate;
 219
 220   const char *const constraint;
 221
 222   ENUM_BITFIELD(machine_mode) const mode : 16;
 223
 224   const char strict_low;
 225
 226   const char eliminable;
 227 };
 228
 229 /* Legal values for insn_data.output_format.  Indicate what type of data
 230    is stored in insn_data.output.  */
 231 #define INSN_OUTPUT_FORMAT_NONE         0       /* abort */
 232 #define INSN_OUTPUT_FORMAT_SINGLE       1       /* const char * */
 233 #define INSN_OUTPUT_FORMAT_MULTI        2       /* const char * const * */
 234 #define INSN_OUTPUT_FORMAT_FUNCTION     3       /* const char * (*)(...) */
 235
 236 struct insn_data
 237 {
 238   const char *const name;
 239 #if HAVE_DESIGNATED_INITIALIZERS
 240   union {
 241     const char *single;
 242     const char *const *multi;
 243     insn_output_fn function;
 244   } output;
 245 #else
 246   struct {
 247     const char *single;
 248     const char *const *multi;
 249     insn_output_fn function;
 250   } output;
 251 #endif
 252   const insn_gen_fn genfun;
 253   const struct insn_operand_data *const operand;
 254
 255   const char n_operands;
 256   const char n_dups;
 257   const char n_alternatives;
 258   const char output_format;
 259 };
 260
 261 extern const struct insn_data insn_data[];