gcc/lra-int.h

   1 /* Local Register Allocator (LRA) intercommunication header file.
   2    Copyright (C) 2010, 2011, 2012
   3    Free Software Foundation, Inc.
   4    Contributed by Vladimir Makarov <vmakarov@redhat.com>.
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #include "lra.h"
  23 #include "bitmap.h"
  24 #include "recog.h"
  25 #include "insn-attr.h"
  26 #include "insn-codes.h"
  27
  28 #define lra_assert(c) gcc_checking_assert (c)
  29
  30 /* The parameter used to prevent infinite reloading for an insn.  Each
  31    insn operands might require a reload and, if it is a memory, its
  32    base and index registers might require a reload too.  */
  33 #define LRA_MAX_INSN_RELOADS (MAX_RECOG_OPERANDS * 3)
  34
  35 /* Return the hard register which given pseudo REGNO assigned to.
  36    Negative value means that the register got memory or we don't know
  37    allocation yet.  */
  38 static inline int
  39 lra_get_regno_hard_regno (int regno)
  40 {
  41   resize_reg_info ();
  42   return reg_renumber[regno];
  43 }
  44
  45 typedef struct lra_live_range *lra_live_range_t;
  46
  47 /* The structure describes program points where a given pseudo lives.
  48    The live ranges can be used to find conflicts with other pseudos.
  49    If the live ranges of two pseudos are intersected, the pseudos are
  50    in conflict.  */
  51 struct lra_live_range
  52 {
  53   /* Pseudo regno whose live range is described by given
  54      structure.  */
  55   int regno;
  56   /* Program point range.  */
  57   int start, finish;
  58   /* Next structure describing program points where the pseudo
  59      lives.  */
  60   lra_live_range_t next;
  61   /* Pointer to structures with the same start.  */
  62   lra_live_range_t start_next;
  63 };
  64
  65 typedef struct lra_copy *lra_copy_t;
  66
  67 /* Copy between pseudos which affects assigning hard registers.  */
  68 struct lra_copy
  69 {
  70   /* True if regno1 is the destination of the copy.  */
  71   bool regno1_dest_p;
  72   /* Execution frequency of the copy.  */
  73   int freq;
  74   /* Pseudos connected by the copy.  REGNO1 < REGNO2.  */
  75   int regno1, regno2;
  76   /* Next copy with correspondingly REGNO1 and REGNO2.  */
  77   lra_copy_t regno1_next, regno2_next;
  78 };
  79
  80 /* Common info about a register (pseudo or hard register).  */
  81 struct lra_reg
  82 {
  83   /* Bitmap of UIDs of insns (including debug insns) referring the
  84      reg.  */
  85   bitmap_head insn_bitmap;
  86   /* The following fields are defined only for pseudos.  */
  87   /* Hard registers with which the pseudo conflicts.  */
  88   HARD_REG_SET conflict_hard_regs;
  89   /* We assign hard registers to reload pseudos which can occur in few
  90      places.  So two hard register preferences are enough for them.
  91      The following fields define the preferred hard registers.  If
  92      there are no such hard registers the first field value is
  93      negative.  If there is only one preferred hard register, the 2nd
  94      field is negative.  */
  95   int preferred_hard_regno1, preferred_hard_regno2;
  96   /* Profits to use the corresponding preferred hard registers.  If
  97      the both hard registers defined, the first hard register has not
  98      less profit than the second one.  */
  99   int preferred_hard_regno_profit1, preferred_hard_regno_profit2;
 100 #ifdef STACK_REGS
 101   /* True if the pseudo should not be assigned to a stack register.  */
 102   bool no_stack_p;
 103 #endif
 104 #ifdef ENABLE_CHECKING
 105   /* True if the pseudo crosses a call.  It is setup in lra-lives.c
 106      and used to check that the pseudo crossing a call did not get a
 107      call used hard register.  */
 108   bool call_p;
 109 #endif
 110   /* Number of references and execution frequencies of the register in
 111      *non-debug* insns.  */
 112   int nrefs, freq;
 113   int last_reload;
 114   /* Regno used to undo the inheritance.  It can be non-zero only
 115      between couple of inheritance and undo inheritance passes.  */
 116   int restore_regno;
 117   /* Value holding by register.  If the pseudos have the same value
 118      they do not conflict.  */
 119   int val;
 120   /* These members are set up in lra-lives.c and updated in
 121      lra-coalesce.c.  */
 122   /* The biggest size mode in which each pseudo reg is referred in
 123      whole function (possibly via subreg).  */
 124   enum machine_mode biggest_mode;
 125   /* Live ranges of the pseudo.  */
 126   lra_live_range_t live_ranges;
 127   /* This member is set up in lra-lives.c for subsequent
 128      assignments.  */
 129   lra_copy_t copies;
 130 };
 131
 132 /* References to the common info about each register.  */
 133 extern struct lra_reg *lra_reg_info;
 134
 135 /* Static info about each insn operand (common for all insns with the
 136    same ICODE).  Warning: if the structure definition is changed, the
 137    initializer for debug_operand_data in lra.c should be changed
 138    too.  */
 139 struct lra_operand_data
 140 {
 141   /* The machine description constraint string of the operand.  */
 142   const char *constraint;
 143   /* It is taken only from machine description (which is different
 144      from recog_data.operand_mode) and can be of VOIDmode.  */
 145   ENUM_BITFIELD(machine_mode) mode : 16;
 146   /* The type of the operand (in/out/inout).  */
 147   ENUM_BITFIELD (op_type) type : 8;
 148   /* Through if accessed through STRICT_LOW.  */
 149   unsigned int strict_low : 1;
 150   /* True if the operand is an operator.  */
 151   unsigned int is_operator : 1;
 152   /* True if there is an early clobber alternative for this operand.
 153      This field is set up every time when corresponding
 154      operand_alternative in lra_static_insn_data is set up.  */
 155   unsigned int early_clobber : 1;
 156   /* True if the operand is an address.  */
 157   unsigned int is_address : 1;
 158 };
 159
 160 /* Info about register occurrence in an insn.  */
 161 struct lra_insn_reg
 162 {
 163   /* The biggest mode through which the insn refers to the register
 164      occurrence (remember the register can be accessed through a
 165      subreg in the insn).  */
 166   ENUM_BITFIELD(machine_mode) biggest_mode : 16;
 167   /* The type of the corresponding operand which is the register.  */
 168   ENUM_BITFIELD (op_type) type : 8;
 169   /* True if the reg is accessed through a subreg and the subreg is
 170      just a part of the register.  */
 171   unsigned int subreg_p : 1;
 172   /* True if there is an early clobber alternative for this
 173      operand.  */
 174   unsigned int early_clobber : 1;
 175   /* The corresponding regno of the register.  */
 176   int regno;
 177   /* Next reg info of the same insn.  */
 178   struct lra_insn_reg *next;
 179 };
 180
 181 /* Static part (common info for insns with the same ICODE) of LRA
 182    internal insn info. It exists in at most one exemplar for each
 183    non-negative ICODE. There is only one exception. Each asm insn has
 184    own structure.  Warning: if the structure definition is changed,
 185    the initializer for debug_insn_static_data in lra.c should be
 186    changed too.  */
 187 struct lra_static_insn_data
 188 {
 189   /* Static info about each insn operand.  */
 190   struct lra_operand_data *operand;
 191   /* Each duplication refers to the number of the corresponding
 192      operand which is duplicated.  */
 193   int *dup_num;
 194   /* The number of an operand marked as commutative, -1 otherwise.  */
 195   int commutative;
 196   /* Number of operands, duplications, and alternatives of the
 197      insn.  */
 198   char n_operands;
 199   char n_dups;
 200   char n_alternatives;
 201   /* Insns in machine description (or clobbers in asm) may contain
 202      explicit hard regs which are not operands.  The following list
 203      describes such hard registers.  */
 204   struct lra_insn_reg *hard_regs;
 205   /* Array [n_alternatives][n_operand] of static constraint info for
 206      given operand in given alternative.  This info can be changed if
 207      the target reg info is changed.  */
 208   struct operand_alternative *operand_alternative;
 209 };
 210
 211 /* LRA internal info about an insn (LRA internal insn
 212    representation).  */
 213 struct lra_insn_recog_data
 214 {
 215   /* The insn code.  */
 216   int icode;
 217   /* The insn itself.  */
 218   rtx insn;
 219   /* Common data for insns with the same ICODE.  Asm insns (their
 220      ICODE is negative) do not share such structures.  */
 221   struct lra_static_insn_data *insn_static_data;
 222   /* Two arrays of size correspondingly equal to the operand and the
 223      duplication numbers: */
 224   rtx **operand_loc; /* The operand locations, NULL if no operands.  */
 225   rtx **dup_loc; /* The dup locations, NULL if no dups.  */
 226   /* Number of hard registers implicitly used in given call insn.  The
 227      value can be NULL or points to array of the hard register numbers
 228      ending with a negative value.  */
 229   int *arg_hard_regs;
 230 #ifdef HAVE_ATTR_enabled
 231   /* Alternative enabled for the insn.  NULL for debug insns.  */
 232   bool *alternative_enabled_p;
 233 #endif
 234   /* The alternative should be used for the insn, -1 if invalid, or we
 235      should try to use any alternative, or the insn is a debug
 236      insn.  */
 237   int used_insn_alternative;
 238   /* The following member value is always NULL for a debug insn.  */
 239   struct lra_insn_reg *regs;
 240 };
 241
 242 typedef struct lra_insn_recog_data *lra_insn_recog_data_t;
 243
 244 /* lra.c: */
 245
 246 extern FILE *lra_dump_file;
 247
 248 extern bool lra_reg_spill_p;
 249
 250 extern HARD_REG_SET lra_no_alloc_regs;
 251
 252 extern int lra_insn_recog_data_len;
 253 extern lra_insn_recog_data_t *lra_insn_recog_data;
 254
 255 extern int lra_curr_reload_num;
 256
 257 extern void lra_push_insn (rtx);
 258 extern void lra_push_insn_by_uid (unsigned int);
 259 extern void lra_push_insn_and_update_insn_regno_info (rtx);
 260 extern rtx lra_pop_insn (void);
 261 extern unsigned int lra_insn_stack_length (void);
 262
 263 extern rtx lra_create_new_reg_with_unique_value (enum machine_mode, rtx,
 264                                                  enum reg_class, const char *);
 265 extern void lra_set_regno_unique_value (int);
 266 extern void lra_invalidate_insn_data (rtx);
 267 extern void lra_set_insn_deleted (rtx);
 268 extern void lra_delete_dead_insn (rtx);
 269 extern void lra_emit_add (rtx, rtx, rtx);
 270 extern void lra_emit_move (rtx, rtx);
 271 extern void lra_update_dups (lra_insn_recog_data_t, signed char *);
 272
 273 extern void lra_process_new_insns (rtx, rtx, rtx, const char *);
 274
 275 extern lra_insn_recog_data_t lra_set_insn_recog_data (rtx);
 276 extern lra_insn_recog_data_t lra_update_insn_recog_data (rtx);
 277 extern void lra_set_used_insn_alternative (rtx, int);
 278 extern void lra_set_used_insn_alternative_by_uid (int, int);
 279
 280 extern void lra_invalidate_insn_regno_info (rtx);
 281 extern void lra_update_insn_regno_info (rtx);
 282 extern struct lra_insn_reg *lra_get_insn_regs (int);
 283
 284 extern void lra_free_copies (void);
 285 extern void lra_create_copy (int, int, int);
 286 extern lra_copy_t lra_get_copy (int);
 287 extern bool lra_former_scratch_p (int);
 288 extern bool lra_former_scratch_operand_p (rtx, int);
 289
 290 extern int lra_constraint_new_regno_start;
 291 extern bitmap_head lra_inheritance_pseudos;
 292 extern bitmap_head lra_split_regs;
 293 extern bitmap_head lra_optional_reload_pseudos;
 294 extern int lra_constraint_new_insn_uid_start;
 295
 296 /* lra-constraints.c: */
 297
 298 extern int lra_constraint_offset (int, enum machine_mode);
 299
 300 extern int lra_constraint_iter;
 301 extern int lra_constraint_iter_after_spill;
 302 extern bool lra_risky_transformations_p;
 303 extern int lra_inheritance_iter;
 304 extern int lra_undo_inheritance_iter;
 305 extern bool lra_constraints (bool);
 306 extern void lra_constraints_init (void);
 307 extern void lra_constraints_finish (void);
 308 extern void lra_inheritance (void);
 309 extern bool lra_undo_inheritance (void);
 310
 311 /* lra-lives.c: */
 312
 313 extern int lra_live_max_point;
 314 extern int *lra_point_freq;
 315
 316 extern int lra_hard_reg_usage[FIRST_PSEUDO_REGISTER];
 317
 318 extern int lra_live_range_iter;
 319 extern void lra_create_live_ranges (bool);
 320 extern lra_live_range_t lra_copy_live_range_list (lra_live_range_t);
 321 extern lra_live_range_t lra_merge_live_ranges (lra_live_range_t,
 322                                                lra_live_range_t);
 323 extern bool lra_intersected_live_ranges_p (lra_live_range_t,
 324                                            lra_live_range_t);
 325 extern void lra_print_live_range_list (FILE *, lra_live_range_t);
 326 extern void lra_debug_live_range_list (lra_live_range_t);
 327 extern void lra_debug_pseudo_live_ranges (int);
 328 extern void lra_debug_live_ranges (void);
 329 extern void lra_clear_live_ranges (void);
 330 extern void lra_live_ranges_init (void);
 331 extern void lra_live_ranges_finish (void);
 332 extern void lra_setup_reload_pseudo_preferenced_hard_reg (int, int, int);
 333
 334 /* lra-assigns.c: */
 335
 336 extern void lra_setup_reg_renumber (int, int, bool);
 337 extern bool lra_assign (void);
 338
 339
 340 /* lra-coalesce.c: */
 341
 342 extern int lra_coalesce_iter;
 343 extern bool lra_coalesce (void);
 344
 345 /* lra-spills.c:  */
 346
 347 extern bool lra_need_for_spills_p (void);
 348 extern void lra_spill (void);
 349 extern void lra_hard_reg_substitution (void);
 350
 351
 352 /* lra-elimination.c: */
 353
 354 extern void lra_debug_elim_table (void);
 355 extern int lra_get_elimination_hard_regno (int);
 356 extern rtx lra_eliminate_regs_1 (rtx, enum machine_mode, bool, bool, bool);
 357 extern void lra_eliminate (bool);
 358
 359 extern void lra_eliminate_reg_if_possible (rtx *);
 360
 361 \f
 362
 363 /* Update insn operands which are duplication of NOP operand.  The
 364    insn is represented by its LRA internal representation ID.  */
 365 static inline void
 366 lra_update_dup (lra_insn_recog_data_t id, int nop)
 367 {
 368   int i;
 369   struct lra_static_insn_data *static_id = id->insn_static_data;
 370
 371   for (i = 0; i < static_id->n_dups; i++)
 372     if (static_id->dup_num[i] == nop)
 373       *id->dup_loc[i] = *id->operand_loc[nop];
 374 }
 375
 376 /* Process operator duplications in insn with ID.  We do it after the
 377    operands processing.  Generally speaking, we could do this probably
 378    simultaneously with operands processing because a common practice
 379    is to enumerate the operators after their operands.  */
 380 static inline void
 381 lra_update_operator_dups (lra_insn_recog_data_t id)
 382 {
 383   int i;
 384   struct lra_static_insn_data *static_id = id->insn_static_data;
 385
 386   for (i = 0; i < static_id->n_dups; i++)
 387     {
 388       int ndup = static_id->dup_num[i];
 389
 390       if (static_id->operand[ndup].is_operator)
 391         *id->dup_loc[i] = *id->operand_loc[ndup];
 392     }
 393 }
 394
 395 /* Return info about INSN.  Set up the info if it is not done yet.  */
 396 static inline lra_insn_recog_data_t
 397 lra_get_insn_recog_data (rtx insn)
 398 {
 399   lra_insn_recog_data_t data;
 400   unsigned int uid = INSN_UID (insn);
 401
 402   if (lra_insn_recog_data_len > (int) uid
 403       && (data = lra_insn_recog_data[uid]) != NULL)
 404     {
 405       /* Check that we did not change insn without updating the insn
 406          info.  */
 407       lra_assert (data->insn == insn
 408                   && (INSN_CODE (insn) < 0
 409                       || data->icode == INSN_CODE (insn)));
 410       return data;
 411     }
 412   return lra_set_insn_recog_data (insn);
 413 }
 414
 415 \f
 416
 417 struct target_lra_int
 418 {
 419   /* Map INSN_UID -> the operand alternative data (NULL if unknown).
 420      We assume that this data is valid until register info is changed
 421      because classes in the data can be changed.  */
 422   struct operand_alternative *x_op_alt_data[LAST_INSN_CODE];
 423 };
 424
 425 extern struct target_lra_int default_target_lra_int;
 426 #if SWITCHABLE_TARGET
 427 extern struct target_lra_int *this_target_lra_int;
 428 #else
 429 #define this_target_lra_int (&default_target_lra_int)
 430 #endif
 431
 432 #define op_alt_data (this_target_lra_int->x_op_alt_data)