gcc/lra-int.h

   1 /* Local Register Allocator (LRA) intercommunication header file.
   2    Copyright (C) 2010-2015 Free Software Foundation, Inc.
   3    Contributed by Vladimir Makarov <vmakarov@redhat.com>.
   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 #ifndef GCC_LRA_INT_H
  22 #define GCC_LRA_INT_H
  23
  24 #define lra_assert(c) gcc_checking_assert (c)
  25
  26 /* The parameter used to prevent infinite reloading for an insn.  Each
  27    insn operands might require a reload and, if it is a memory, its
  28    base and index registers might require a reload too.  */
  29 #define LRA_MAX_INSN_RELOADS (MAX_RECOG_OPERANDS * 3)
  30
  31 typedef struct lra_live_range *lra_live_range_t;
  32
  33 /* The structure describes program points where a given pseudo lives.
  34    The live ranges can be used to find conflicts with other pseudos.
  35    If the live ranges of two pseudos are intersected, the pseudos are
  36    in conflict.  */
  37 struct lra_live_range
  38 {
  39   /* Pseudo regno whose live range is described by given
  40      structure.  */
  41   int regno;
  42   /* Program point range.  */
  43   int start, finish;
  44   /* Next structure describing program points where the pseudo
  45      lives.  */
  46   lra_live_range_t next;
  47   /* Pointer to structures with the same start.  */
  48   lra_live_range_t start_next;
  49 };
  50
  51 typedef struct lra_copy *lra_copy_t;
  52
  53 /* Copy between pseudos which affects assigning hard registers.  */
  54 struct lra_copy
  55 {
  56   /* True if regno1 is the destination of the copy.  */
  57   bool regno1_dest_p;
  58   /* Execution frequency of the copy.  */
  59   int freq;
  60   /* Pseudos connected by the copy.  REGNO1 < REGNO2.  */
  61   int regno1, regno2;
  62   /* Next copy with correspondingly REGNO1 and REGNO2.  */
  63   lra_copy_t regno1_next, regno2_next;
  64 };
  65
  66 /* Common info about a register (pseudo or hard register).  */
  67 struct lra_reg
  68 {
  69   /* Bitmap of UIDs of insns (including debug insns) referring the
  70      reg.  */
  71   bitmap_head insn_bitmap;
  72   /* The following fields are defined only for pseudos.  */
  73   /* Hard registers with which the pseudo conflicts.  */
  74   HARD_REG_SET conflict_hard_regs;
  75   /* Call used registers with which the pseudo conflicts, taking into account
  76      the registers used by functions called from calls which cross the
  77      pseudo.  */
  78   HARD_REG_SET actual_call_used_reg_set;
  79   /* We assign hard registers to reload pseudos which can occur in few
  80      places.  So two hard register preferences are enough for them.
  81      The following fields define the preferred hard registers.  If
  82      there are no such hard registers the first field value is
  83      negative.  If there is only one preferred hard register, the 2nd
  84      field is negative.  */
  85   int preferred_hard_regno1, preferred_hard_regno2;
  86   /* Profits to use the corresponding preferred hard registers.  If
  87      the both hard registers defined, the first hard register has not
  88      less profit than the second one.  */
  89   int preferred_hard_regno_profit1, preferred_hard_regno_profit2;
  90 #ifdef STACK_REGS
  91   /* True if the pseudo should not be assigned to a stack register.  */
  92   bool no_stack_p;
  93 #endif
  94 #ifdef ENABLE_CHECKING
  95   /* True if the pseudo crosses a call.  It is setup in lra-lives.c
  96      and used to check that the pseudo crossing a call did not get a
  97      call used hard register.  */
  98   bool call_p;
  99 #endif
 100   /* Number of references and execution frequencies of the register in
 101      *non-debug* insns.  */
 102   int nrefs, freq;
 103   int last_reload;
 104   /* Regno used to undo the inheritance.  It can be non-zero only
 105      between couple of inheritance and undo inheritance passes.  */
 106   int restore_regno;
 107   /* Value holding by register.  If the pseudos have the same value
 108      they do not conflict.  */
 109   int val;
 110   /* Offset from relative eliminate register to pesudo reg.  */
 111   int offset;
 112   /* These members are set up in lra-lives.c and updated in
 113      lra-coalesce.c.  */
 114   /* The biggest size mode in which each pseudo reg is referred in
 115      whole function (possibly via subreg).  */
 116   machine_mode biggest_mode;
 117   /* Live ranges of the pseudo.  */
 118   lra_live_range_t live_ranges;
 119   /* This member is set up in lra-lives.c for subsequent
 120      assignments.  */
 121   lra_copy_t copies;
 122 };
 123
 124 /* References to the common info about each register.  */
 125 extern struct lra_reg *lra_reg_info;
 126
 127 /* Static info about each insn operand (common for all insns with the
 128    same ICODE).  Warning: if the structure definition is changed, the
 129    initializer for debug_operand_data in lra.c should be changed
 130    too.  */
 131 struct lra_operand_data
 132 {
 133   /* The machine description constraint string of the operand.  */
 134   const char *constraint;
 135   /* It is taken only from machine description (which is different
 136      from recog_data.operand_mode) and can be of VOIDmode.  */
 137   ENUM_BITFIELD(machine_mode) mode : 16;
 138   /* The type of the operand (in/out/inout).  */
 139   ENUM_BITFIELD (op_type) type : 8;
 140   /* Through if accessed through STRICT_LOW.  */
 141   unsigned int strict_low : 1;
 142   /* True if the operand is an operator.  */
 143   unsigned int is_operator : 1;
 144   /* True if there is an early clobber alternative for this operand.
 145      This field is set up every time when corresponding
 146      operand_alternative in lra_static_insn_data is set up.  */
 147   unsigned int early_clobber : 1;
 148   /* True if the operand is an address.  */
 149   unsigned int is_address : 1;
 150 };
 151
 152 /* Info about register occurrence in an insn.  */
 153 struct lra_insn_reg
 154 {
 155   /* The biggest mode through which the insn refers to the register
 156      occurrence (remember the register can be accessed through a
 157      subreg in the insn).  */
 158   ENUM_BITFIELD(machine_mode) biggest_mode : 16;
 159   /* The type of the corresponding operand which is the register.  */
 160   ENUM_BITFIELD (op_type) type : 8;
 161   /* True if the reg is accessed through a subreg and the subreg is
 162      just a part of the register.  */
 163   unsigned int subreg_p : 1;
 164   /* True if there is an early clobber alternative for this
 165      operand.  */
 166   unsigned int early_clobber : 1;
 167   /* The corresponding regno of the register.  */
 168   int regno;
 169   /* Next reg info of the same insn.  */
 170   struct lra_insn_reg *next;
 171 };
 172
 173 /* Static part (common info for insns with the same ICODE) of LRA
 174    internal insn info. It exists in at most one exemplar for each
 175    non-negative ICODE. There is only one exception. Each asm insn has
 176    own structure.  Warning: if the structure definition is changed,
 177    the initializer for debug_insn_static_data in lra.c should be
 178    changed too.  */
 179 struct lra_static_insn_data
 180 {
 181   /* Static info about each insn operand.  */
 182   struct lra_operand_data *operand;
 183   /* Each duplication refers to the number of the corresponding
 184      operand which is duplicated.  */
 185   int *dup_num;
 186   /* The number of an operand marked as commutative, -1 otherwise.  */
 187   int commutative;
 188   /* Number of operands, duplications, and alternatives of the
 189      insn.  */
 190   char n_operands;
 191   char n_dups;
 192   char n_alternatives;
 193   /* Insns in machine description (or clobbers in asm) may contain
 194      explicit hard regs which are not operands.  The following list
 195      describes such hard registers.  */
 196   struct lra_insn_reg *hard_regs;
 197   /* Array [n_alternatives][n_operand] of static constraint info for
 198      given operand in given alternative.  This info can be changed if
 199      the target reg info is changed.  */
 200   const struct operand_alternative *operand_alternative;
 201 };
 202
 203 /* LRA internal info about an insn (LRA internal insn
 204    representation).  */
 205 struct lra_insn_recog_data
 206 {
 207   /* The insn code.  */
 208   int icode;
 209   /* The alternative should be used for the insn, -1 if invalid, or we
 210      should try to use any alternative, or the insn is a debug
 211      insn.  */
 212   int used_insn_alternative;
 213   /* SP offset before the insn relative to one at the func start.  */
 214   HOST_WIDE_INT sp_offset;
 215   /* The insn itself.  */
 216   rtx_insn *insn;
 217   /* Common data for insns with the same ICODE.  Asm insns (their
 218      ICODE is negative) do not share such structures.  */
 219   struct lra_static_insn_data *insn_static_data;
 220   /* Two arrays of size correspondingly equal to the operand and the
 221      duplication numbers: */
 222   rtx **operand_loc; /* The operand locations, NULL if no operands.  */
 223   rtx **dup_loc; /* The dup locations, NULL if no dups.  */
 224   /* Number of hard registers implicitly used/clobbered in given call
 225      insn.  The value can be NULL or points to array of the hard
 226      register numbers ending with a negative value.  To differ
 227      clobbered and used hard regs, clobbered hard regs are incremented
 228      by FIRST_PSEUDO_REGISTER.  */
 229   int *arg_hard_regs;
 230   /* Cached value of get_preferred_alternatives.  */
 231   alternative_mask preferred_alternatives;
 232   /* The following member value is always NULL for a debug insn.  */
 233   struct lra_insn_reg *regs;
 234 };
 235
 236 typedef struct lra_insn_recog_data *lra_insn_recog_data_t;
 237
 238 /* Whether the clobber is used temporary in LRA.  */
 239 #define LRA_TEMP_CLOBBER_P(x) \
 240   (RTL_FLAG_CHECK1 ("TEMP_CLOBBER_P", (x), CLOBBER)->unchanging)
 241
 242 /* Cost factor for each additional reload and maximal cost reject for
 243    insn reloads.  One might ask about such strange numbers.  Their
 244    values occurred historically from former reload pass.  */
 245 #define LRA_LOSER_COST_FACTOR 6
 246 #define LRA_MAX_REJECT 600
 247
 248 /* Maximum allowed number of assignment pass iterations after the
 249    latest spill pass when any former reload pseudo was spilled.  It is
 250    for preventing LRA cycling in a bug case.  */
 251 #define LRA_MAX_ASSIGNMENT_ITERATION_NUMBER 30
 252
 253 /* The maximal number of inheritance/split passes in LRA.  It should
 254    be more 1 in order to perform caller saves transformations and much
 255    less MAX_CONSTRAINT_ITERATION_NUMBER to prevent LRA to do as many
 256    as permitted constraint passes in some complicated cases.  The
 257    first inheritance/split pass has a biggest impact on generated code
 258    quality.  Each subsequent affects generated code in less degree.
 259    For example, the 3rd pass does not change generated SPEC2000 code
 260    at all on x86-64.  */
 261 #define LRA_MAX_INHERITANCE_PASSES 2
 262
 263 #if LRA_MAX_INHERITANCE_PASSES <= 0 \
 264     || LRA_MAX_INHERITANCE_PASSES >= LRA_MAX_ASSIGNMENT_ITERATION_NUMBER - 8
 265 #error wrong LRA_MAX_INHERITANCE_PASSES value
 266 #endif
 267
 268 /* Analogous macro to the above one but for rematerialization.  */
 269 #define LRA_MAX_REMATERIALIZATION_PASSES 2
 270
 271 #if LRA_MAX_REMATERIALIZATION_PASSES <= 0 \
 272     || LRA_MAX_REMATERIALIZATION_PASSES >= LRA_MAX_ASSIGNMENT_ITERATION_NUMBER - 8
 273 #error wrong LRA_MAX_REMATERIALIZATION_PASSES value
 274 #endif
 275
 276 /* lra.c: */
 277
 278 extern FILE *lra_dump_file;
 279
 280 extern bool lra_reg_spill_p;
 281
 282 extern HARD_REG_SET lra_no_alloc_regs;
 283
 284 extern int lra_insn_recog_data_len;
 285 extern lra_insn_recog_data_t *lra_insn_recog_data;
 286
 287 extern int lra_curr_reload_num;
 288
 289 extern void lra_dump_bitmap_with_title (const char *, bitmap, int);
 290 extern void lra_push_insn (rtx_insn *);
 291 extern void lra_push_insn_by_uid (unsigned int);
 292 extern void lra_push_insn_and_update_insn_regno_info (rtx_insn *);
 293 extern rtx_insn *lra_pop_insn (void);
 294 extern unsigned int lra_insn_stack_length (void);
 295
 296 extern rtx lra_create_new_reg_with_unique_value (machine_mode, rtx,
 297                                                  enum reg_class, const char *);
 298 extern void lra_set_regno_unique_value (int);
 299 extern void lra_invalidate_insn_data (rtx_insn *);
 300 extern void lra_set_insn_deleted (rtx_insn *);
 301 extern void lra_delete_dead_insn (rtx_insn *);
 302 extern void lra_emit_add (rtx, rtx, rtx);
 303 extern void lra_emit_move (rtx, rtx);
 304 extern void lra_update_dups (lra_insn_recog_data_t, signed char *);
 305
 306 extern void lra_process_new_insns (rtx_insn *, rtx_insn *, rtx_insn *,
 307                                    const char *);
 308
 309 extern bool lra_substitute_pseudo (rtx *, int, rtx, bool);
 310 extern bool lra_substitute_pseudo_within_insn (rtx_insn *, int, rtx, bool);
 311
 312 extern lra_insn_recog_data_t lra_set_insn_recog_data (rtx_insn *);
 313 extern lra_insn_recog_data_t lra_update_insn_recog_data (rtx_insn *);
 314 extern void lra_set_used_insn_alternative (rtx_insn *, int);
 315 extern void lra_set_used_insn_alternative_by_uid (int, int);
 316
 317 extern void lra_invalidate_insn_regno_info (rtx_insn *);
 318 extern void lra_update_insn_regno_info (rtx_insn *);
 319 extern struct lra_insn_reg *lra_get_insn_regs (int);
 320
 321 extern void lra_free_copies (void);
 322 extern void lra_create_copy (int, int, int);
 323 extern lra_copy_t lra_get_copy (int);
 324 extern bool lra_former_scratch_p (int);
 325 extern bool lra_former_scratch_operand_p (rtx_insn *, int);
 326 extern void lra_register_new_scratch_op (rtx_insn *, int);
 327
 328 extern int lra_new_regno_start;
 329 extern int lra_constraint_new_regno_start;
 330 extern int lra_bad_spill_regno_start;
 331 extern bitmap_head lra_inheritance_pseudos;
 332 extern bitmap_head lra_split_regs;
 333 extern bitmap_head lra_subreg_reload_pseudos;
 334 extern bitmap_head lra_optional_reload_pseudos;
 335
 336 /* lra-constraints.c: */
 337
 338 extern void lra_init_equiv (void);
 339 extern int lra_constraint_offset (int, machine_mode);
 340
 341 extern int lra_constraint_iter;
 342 extern bool lra_risky_transformations_p;
 343 extern int lra_inheritance_iter;
 344 extern int lra_undo_inheritance_iter;
 345 extern bool lra_constrain_insn (rtx_insn *);
 346 extern bool lra_constraints (bool);
 347 extern void lra_constraints_init (void);
 348 extern void lra_constraints_finish (void);
 349 extern void lra_inheritance (void);
 350 extern bool lra_undo_inheritance (void);
 351
 352 /* lra-lives.c: */
 353
 354 extern int lra_live_max_point;
 355 extern int *lra_point_freq;
 356
 357 extern int lra_hard_reg_usage[FIRST_PSEUDO_REGISTER];
 358
 359 extern int lra_live_range_iter;
 360 extern void lra_create_live_ranges (bool, bool);
 361 extern lra_live_range_t lra_copy_live_range_list (lra_live_range_t);
 362 extern lra_live_range_t lra_merge_live_ranges (lra_live_range_t,
 363                                                lra_live_range_t);
 364 extern bool lra_intersected_live_ranges_p (lra_live_range_t,
 365                                            lra_live_range_t);
 366 extern void lra_print_live_range_list (FILE *, lra_live_range_t);
 367 extern void debug (lra_live_range &ref);
 368 extern void debug (lra_live_range *ptr);
 369 extern void lra_debug_live_range_list (lra_live_range_t);
 370 extern void lra_debug_pseudo_live_ranges (int);
 371 extern void lra_debug_live_ranges (void);
 372 extern void lra_clear_live_ranges (void);
 373 extern void lra_live_ranges_init (void);
 374 extern void lra_live_ranges_finish (void);
 375 extern void lra_setup_reload_pseudo_preferenced_hard_reg (int, int, int);
 376
 377 /* lra-assigns.c: */
 378
 379 extern int lra_assignment_iter;
 380 extern int lra_assignment_iter_after_spill;
 381 extern void lra_setup_reg_renumber (int, int, bool);
 382 extern bool lra_assign (void);
 383
 384
 385 /* lra-coalesce.c: */
 386
 387 extern int lra_coalesce_iter;
 388 extern bool lra_coalesce (void);
 389
 390 /* lra-spills.c:  */
 391
 392 extern bool lra_need_for_spills_p (void);
 393 extern void lra_spill (void);
 394 extern void lra_final_code_change (void);
 395
 396 /* lra-remat.c:  */
 397
 398 extern int lra_rematerialization_iter;
 399 extern bool lra_remat (void);
 400
 401 /* lra-elimination.c: */
 402
 403 extern void lra_debug_elim_table (void);
 404 extern int lra_get_elimination_hard_regno (int);
 405 extern rtx lra_eliminate_regs_1 (rtx_insn *, rtx, machine_mode,
 406                                  bool, bool, HOST_WIDE_INT, bool);
 407 extern void eliminate_regs_in_insn (rtx_insn *insn, bool, bool, HOST_WIDE_INT);
 408 extern void lra_eliminate (bool, bool);
 409
 410 extern void lra_eliminate_reg_if_possible (rtx *);
 411
 412 \f
 413
 414 /* Return the hard register which given pseudo REGNO assigned to.
 415    Negative value means that the register got memory or we don't know
 416    allocation yet.  */
 417 static inline int
 418 lra_get_regno_hard_regno (int regno)
 419 {
 420   resize_reg_info ();
 421   return reg_renumber[regno];
 422 }
 423
 424 /* Change class of pseudo REGNO to NEW_CLASS.  Print info about it
 425    using TITLE.  Output a new line if NL_P.  */
 426 static void inline
 427 lra_change_class (int regno, enum reg_class new_class,
 428                   const char *title, bool nl_p)
 429 {
 430   lra_assert (regno >= FIRST_PSEUDO_REGISTER);
 431   if (lra_dump_file != NULL)
 432     fprintf (lra_dump_file, "%s class %s for r%d",
 433              title, reg_class_names[new_class], regno);
 434   setup_reg_classes (regno, new_class, NO_REGS, new_class);
 435   if (lra_dump_file != NULL && nl_p)
 436     fprintf (lra_dump_file, "\n");
 437 }
 438
 439 /* Update insn operands which are duplication of NOP operand.  The
 440    insn is represented by its LRA internal representation ID.  */
 441 static inline void
 442 lra_update_dup (lra_insn_recog_data_t id, int nop)
 443 {
 444   int i;
 445   struct lra_static_insn_data *static_id = id->insn_static_data;
 446
 447   for (i = 0; i < static_id->n_dups; i++)
 448     if (static_id->dup_num[i] == nop)
 449       *id->dup_loc[i] = *id->operand_loc[nop];
 450 }
 451
 452 /* Process operator duplications in insn with ID.  We do it after the
 453    operands processing.  Generally speaking, we could do this probably
 454    simultaneously with operands processing because a common practice
 455    is to enumerate the operators after their operands.  */
 456 static inline void
 457 lra_update_operator_dups (lra_insn_recog_data_t id)
 458 {
 459   int i;
 460   struct lra_static_insn_data *static_id = id->insn_static_data;
 461
 462   for (i = 0; i < static_id->n_dups; i++)
 463     {
 464       int ndup = static_id->dup_num[i];
 465
 466       if (static_id->operand[ndup].is_operator)
 467         *id->dup_loc[i] = *id->operand_loc[ndup];
 468     }
 469 }
 470
 471 /* Return info about INSN.  Set up the info if it is not done yet.  */
 472 static inline lra_insn_recog_data_t
 473 lra_get_insn_recog_data (rtx_insn *insn)
 474 {
 475   lra_insn_recog_data_t data;
 476   unsigned int uid = INSN_UID (insn);
 477
 478   if (lra_insn_recog_data_len > (int) uid
 479       && (data = lra_insn_recog_data[uid]) != NULL)
 480     {
 481       /* Check that we did not change insn without updating the insn
 482          info.  */
 483       lra_assert (data->insn == insn
 484                   && (INSN_CODE (insn) < 0
 485                       || data->icode == INSN_CODE (insn)));
 486       return data;
 487     }
 488   return lra_set_insn_recog_data (insn);
 489 }
 490
 491 /* Update offset from pseudos with VAL by INCR.  */
 492 static inline void
 493 lra_update_reg_val_offset (int val, int incr)
 494 {
 495   int i;
 496
 497   for (i = FIRST_PSEUDO_REGISTER; i < max_reg_num (); i++)
 498     {
 499       if (lra_reg_info[i].val == val)
 500         lra_reg_info[i].offset += incr;
 501     }
 502 }
 503
 504 /* Return true if register content is equal to VAL with OFFSET.  */
 505 static inline bool
 506 lra_reg_val_equal_p (int regno, int val, int offset)
 507 {
 508   if (lra_reg_info[regno].val == val
 509       && lra_reg_info[regno].offset == offset)
 510     return true;
 511
 512   return false;
 513 }
 514
 515 /* Assign value of register FROM to TO.  */
 516 static inline void
 517 lra_assign_reg_val (int from, int to)
 518 {
 519   lra_reg_info[to].val = lra_reg_info[from].val;
 520   lra_reg_info[to].offset = lra_reg_info[from].offset;
 521 }
 522
 523 #endif /* GCC_LRA_INT_H */