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    2005, 2006, 2007, 2008, 2009 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 3, 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 COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 /* Random number that should be large enough for all purposes.  */
  22 #define MAX_RECOG_ALTERNATIVES 30
  23
  24 /* Types of operands.  */
  25 enum op_type {
  26   OP_IN,
  27   OP_OUT,
  28   OP_INOUT
  29 };
  30
  31 struct operand_alternative
  32 {
  33   /* Pointer to the beginning of the constraint string for this alternative,
  34      for easier access by alternative number.  */
  35   const char *constraint;
  36
  37   /* The register class valid for this alternative (possibly NO_REGS).  */
  38   enum reg_class cl;
  39
  40   /* "Badness" of this alternative, computed from number of '?' and '!'
  41      characters in the constraint string.  */
  42   unsigned int reject;
  43
  44   /* -1 if no matching constraint was found, or an operand number.  */
  45   int matches;
  46   /* The same information, but reversed: -1 if this operand is not
  47      matched by any other, or the operand number of the operand that
  48      matches this one.  */
  49   int matched;
  50
  51   /* Nonzero if '&' was found in the constraint string.  */
  52   unsigned int earlyclobber:1;
  53   /* Nonzero if TARGET_MEM_CONSTRAINT was found in the constraint
  54      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 *, const char **);
  76 extern bool validate_change (rtx, rtx *, rtx, bool);
  77 extern bool validate_unshare_change (rtx, rtx *, rtx, bool);
  78 extern bool canonicalize_change_group (rtx insn, rtx x);
  79 extern int insn_invalid_p (rtx);
  80 extern int verify_changes (int);
  81 extern void confirm_change_group (void);
  82 extern int apply_change_group (void);
  83 extern int num_validated_changes (void);
  84 extern void cancel_changes (int);
  85 extern int constrain_operands (int);
  86 extern int constrain_operands_cached (int);
  87 extern int memory_address_p (enum machine_mode, rtx);
  88 extern int strict_memory_address_p (enum machine_mode, rtx);
  89 extern int validate_replace_rtx (rtx, rtx, rtx);
  90 extern int validate_replace_rtx_part (rtx, rtx, rtx *, rtx);
  91 extern int validate_replace_rtx_part_nosimplify (rtx, rtx, rtx *, rtx);
  92 extern void validate_replace_rtx_group (rtx, rtx, rtx);
  93 extern void validate_replace_src_group (rtx, rtx, rtx);
  94 extern bool validate_simplify_insn (rtx insn);
  95 extern int num_changes_pending (void);
  96 #ifdef HAVE_cc0
  97 extern int next_insn_tests_no_inequality (rtx);
  98 #endif
  99 extern int reg_fits_class_p (rtx, enum reg_class, int, enum machine_mode);
 100
 101 extern int offsettable_memref_p (rtx);
 102 extern int offsettable_nonstrict_memref_p (rtx);
 103 extern int offsettable_address_p (int, enum machine_mode, rtx);
 104 extern int mode_dependent_address_p (rtx);
 105
 106 extern int recog (rtx, rtx, int *);
 107 #ifndef GENERATOR_FILE
 108 static inline int recog_memoized (rtx insn);
 109 #endif
 110 extern void add_clobbers (rtx, int);
 111 extern int added_clobbers_hard_reg_p (int);
 112 extern void insn_extract (rtx);
 113 extern void extract_insn (rtx);
 114 extern void extract_constrain_insn_cached (rtx);
 115 extern void extract_insn_cached (rtx);
 116 extern void preprocess_constraints (void);
 117 extern rtx peep2_next_insn (int);
 118 extern int peep2_regno_dead_p (int, int);
 119 extern int peep2_reg_dead_p (int, rtx);
 120 #ifdef CLEAR_HARD_REG_SET
 121 extern rtx peep2_find_free_register (int, int, const char *,
 122                                      enum machine_mode, HARD_REG_SET *);
 123 #endif
 124 extern rtx peephole2_insns (rtx, rtx, int *);
 125
 126 extern int store_data_bypass_p (rtx, rtx);
 127 extern int if_test_bypass_p (rtx, rtx);
 128
 129 #ifndef GENERATOR_FILE
 130 /* Try recognizing the instruction INSN,
 131    and return the code number that results.
 132    Remember the code so that repeated calls do not
 133    need to spend the time for actual rerecognition.
 134
 135    This function is the normal interface to instruction recognition.
 136    The automatically-generated function `recog' is normally called
 137    through this one.  */
 138
 139 static inline int
 140 recog_memoized (rtx insn)
 141 {
 142   if (INSN_CODE (insn) < 0)
 143     INSN_CODE (insn) = recog (PATTERN (insn), insn, 0);
 144   return INSN_CODE (insn);
 145 }
 146 #endif
 147
 148 /* Skip chars until the next ',' or the end of the string.  This is
 149    useful to skip alternatives in a constraint string.  */
 150 static inline const char *
 151 skip_alternative (const char *p)
 152 {
 153   const char *r = p;
 154   while (*r != '\0' && *r != ',')
 155     r++;
 156   if (*r == ',')
 157     r++;
 158   return r;
 159 }
 160
 161 /* Nonzero means volatile operands are recognized.  */
 162 extern int volatile_ok;
 163
 164 /* Set by constrain_operands to the number of the alternative that
 165    matched.  */
 166 extern int which_alternative;
 167
 168 /* The following vectors hold the results from insn_extract.  */
 169
 170 struct recog_data
 171 {
 172   /* It is very tempting to make the 5 operand related arrays into a
 173      structure and index on that.  However, to be source compatible
 174      with all of the existing md file insn constraints and output
 175      templates, we need `operand' as a flat array.  Without that
 176      member, making an array for the rest seems pointless.  */
 177
 178   /* Gives value of operand N.  */
 179   rtx operand[MAX_RECOG_OPERANDS];
 180
 181   /* Gives location where operand N was found.  */
 182   rtx *operand_loc[MAX_RECOG_OPERANDS];
 183
 184   /* Gives the constraint string for operand N.  */
 185   const char *constraints[MAX_RECOG_OPERANDS];
 186
 187   /* Gives the mode of operand N.  */
 188   enum machine_mode operand_mode[MAX_RECOG_OPERANDS];
 189
 190   /* Gives the type (in, out, inout) for operand N.  */
 191   enum op_type operand_type[MAX_RECOG_OPERANDS];
 192
 193   /* Gives location where the Nth duplicate-appearance of an operand
 194      was found.  This is something that matched MATCH_DUP.  */
 195   rtx *dup_loc[MAX_DUP_OPERANDS];
 196
 197   /* Gives the operand number that was duplicated in the Nth
 198      duplicate-appearance of an operand.  */
 199   char dup_num[MAX_DUP_OPERANDS];
 200
 201   /* ??? Note that these are `char' instead of `unsigned char' to (try to)
 202      avoid certain lossage from K&R C, wherein `unsigned char' default
 203      promotes to `unsigned int' instead of `int' as in ISO C.  As of 1999,
 204      the most common places to bootstrap from K&R C are SunOS and HPUX,
 205      both of which have signed characters by default.  The only other
 206      supported natives that have both K&R C and unsigned characters are
 207      ROMP and Irix 3, and neither have been seen for a while, but do
 208      continue to consider unsignedness when performing arithmetic inside
 209      a comparison.  */
 210
 211   /* The number of operands of the insn.  */
 212   char n_operands;
 213
 214   /* The number of MATCH_DUPs in the insn.  */
 215   char n_dups;
 216
 217   /* The number of alternatives in the constraints for the insn.  */
 218   char n_alternatives;
 219
 220   /* Specifies whether an insn alternative is enabled using the
 221      `enabled' attribute in the insn pattern definition.  For back
 222      ends not using the `enabled' attribute the array fields are
 223      always set to `true' in expand_insn.  */
 224   bool alternative_enabled_p [MAX_RECOG_ALTERNATIVES];
 225
 226   /* In case we are caching, hold insn data was generated for.  */
 227   rtx insn;
 228 };
 229
 230 extern struct recog_data recog_data;
 231
 232 /* Contains a vector of operand_alternative structures for every operand.
 233    Set up by preprocess_constraints.  */
 234 extern struct operand_alternative recog_op_alt[MAX_RECOG_OPERANDS][MAX_RECOG_ALTERNATIVES];
 235
 236 /* A table defined in insn-output.c that give information about
 237    each insn-code value.  */
 238
 239 typedef int (*insn_operand_predicate_fn) (rtx, enum machine_mode);
 240 typedef const char * (*insn_output_fn) (rtx *, rtx);
 241 typedef rtx (*insn_gen_fn) (rtx, ...);
 242
 243 struct insn_operand_data
 244 {
 245   const insn_operand_predicate_fn predicate;
 246
 247   const char *const constraint;
 248
 249   ENUM_BITFIELD(machine_mode) const mode : 16;
 250
 251   const char strict_low;
 252
 253   const char eliminable;
 254 };
 255
 256 /* Legal values for insn_data.output_format.  Indicate what type of data
 257    is stored in insn_data.output.  */
 258 #define INSN_OUTPUT_FORMAT_NONE         0       /* abort */
 259 #define INSN_OUTPUT_FORMAT_SINGLE       1       /* const char * */
 260 #define INSN_OUTPUT_FORMAT_MULTI        2       /* const char * const * */
 261 #define INSN_OUTPUT_FORMAT_FUNCTION     3       /* const char * (*)(...) */
 262
 263 struct insn_data
 264 {
 265   const char *const name;
 266 #if HAVE_DESIGNATED_INITIALIZERS
 267   union {
 268     const char *single;
 269     const char *const *multi;
 270     insn_output_fn function;
 271   } output;
 272 #else
 273   struct {
 274     const char *single;
 275     const char *const *multi;
 276     insn_output_fn function;
 277   } output;
 278 #endif
 279   const insn_gen_fn genfun;
 280   const struct insn_operand_data *const operand;
 281
 282   const char n_operands;
 283   const char n_dups;
 284   const char n_alternatives;
 285   const char output_format;
 286 };
 287
 288 extern const struct insn_data insn_data[];
 289 extern int peep2_current_count;