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   /* Pool allocation new operator.  */
  51   inline void *operator new (size_t)
  52   {
  53     return pool.allocate ();
  54   }
  55
  56   /* Delete operator utilizing pool allocation.  */
  57   inline void operator delete (void *ptr)
  58   {
  59     pool.remove ((lra_live_range *) ptr);
  60   }
  61
  62   /* Memory allocation pool.  */
  63   static pool_allocator<lra_live_range> pool;
  64 };
  65
  66 typedef struct lra_copy *lra_copy_t;
  67
  68 /* Copy between pseudos which affects assigning hard registers.  */
  69 struct lra_copy
  70 {
  71   /* True if regno1 is the destination of the copy.  */
  72   bool regno1_dest_p;
  73   /* Execution frequency of the copy.  */
  74   int freq;
  75   /* Pseudos connected by the copy.  REGNO1 < REGNO2.  */
  76   int regno1, regno2;
  77   /* Next copy with correspondingly REGNO1 and REGNO2.  */
  78   lra_copy_t regno1_next, regno2_next;
  79
  80   /* Pool allocation new operator.  */
  81   inline void *operator new (size_t)
  82   {
  83     return pool.allocate ();
  84   }
  85
  86   /* Delete operator utilizing pool allocation.  */
  87   inline void operator delete (void *ptr)
  88   {
  89     pool.remove ((lra_copy *) ptr);
  90   }
  91
  92   /* Memory allocation pool.  */
  93   static pool_allocator<lra_copy> pool;
  94
  95 };
  96
  97 /* Common info about a register (pseudo or hard register).  */
  98 struct lra_reg
  99 {
 100   /* Bitmap of UIDs of insns (including debug insns) referring the
 101      reg.  */
 102   bitmap_head insn_bitmap;
 103   /* The following fields are defined only for pseudos.  */
 104   /* Hard registers with which the pseudo conflicts.  */
 105   HARD_REG_SET conflict_hard_regs;
 106   /* Call used registers with which the pseudo conflicts, taking into account
 107      the registers used by functions called from calls which cross the
 108      pseudo.  */
 109   HARD_REG_SET actual_call_used_reg_set;
 110   /* We assign hard registers to reload pseudos which can occur in few
 111      places.  So two hard register preferences are enough for them.
 112      The following fields define the preferred hard registers.  If
 113      there are no such hard registers the first field value is
 114      negative.  If there is only one preferred hard register, the 2nd
 115      field is negative.  */
 116   int preferred_hard_regno1, preferred_hard_regno2;
 117   /* Profits to use the corresponding preferred hard registers.  If
 118      the both hard registers defined, the first hard register has not
 119      less profit than the second one.  */
 120   int preferred_hard_regno_profit1, preferred_hard_regno_profit2;
 121 #ifdef STACK_REGS
 122   /* True if the pseudo should not be assigned to a stack register.  */
 123   bool no_stack_p;
 124 #endif
 125 #ifdef ENABLE_CHECKING
 126   /* True if the pseudo crosses a call.  It is setup in lra-lives.c
 127      and used to check that the pseudo crossing a call did not get a
 128      call used hard register.  */
 129   bool call_p;
 130 #endif
 131   /* Number of references and execution frequencies of the register in
 132      *non-debug* insns.  */
 133   int nrefs, freq;
 134   int last_reload;
 135   /* Regno used to undo the inheritance.  It can be non-zero only
 136      between couple of inheritance and undo inheritance passes.  */
 137   int restore_regno;
 138   /* Value holding by register.  If the pseudos have the same value
 139      they do not conflict.  */
 140   int val;
 141   /* Offset from relative eliminate register to pesudo reg.  */
 142   int offset;
 143   /* These members are set up in lra-lives.c and updated in
 144      lra-coalesce.c.  */
 145   /* The biggest size mode in which each pseudo reg is referred in
 146      whole function (possibly via subreg).  */
 147   machine_mode biggest_mode;
 148   /* Live ranges of the pseudo.  */
 149   lra_live_range_t live_ranges;
 150   /* This member is set up in lra-lives.c for subsequent
 151      assignments.  */
 152   lra_copy_t copies;
 153 };
 154
 155 /* References to the common info about each register.  */
 156 extern struct lra_reg *lra_reg_info;
 157
 158 /* Static info about each insn operand (common for all insns with the
 159    same ICODE).  Warning: if the structure definition is changed, the
 160    initializer for debug_operand_data in lra.c should be changed
 161    too.  */
 162 struct lra_operand_data
 163 {
 164   /* The machine description constraint string of the operand.  */
 165   const char *constraint;
 166   /* It is taken only from machine description (which is different
 167      from recog_data.operand_mode) and can be of VOIDmode.  */
 168   ENUM_BITFIELD(machine_mode) mode : 16;
 169   /* The type of the operand (in/out/inout).  */
 170   ENUM_BITFIELD (op_type) type : 8;
 171   /* Through if accessed through STRICT_LOW.  */
 172   unsigned int strict_low : 1;
 173   /* True if the operand is an operator.  */
 174   unsigned int is_operator : 1;
 175   /* True if there is an early clobber alternative for this operand.
 176      This field is set up every time when corresponding
 177      operand_alternative in lra_static_insn_data is set up.  */
 178   unsigned int early_clobber : 1;
 179   /* True if the operand is an address.  */
 180   unsigned int is_address : 1;
 181 };
 182
 183 /* Info about register occurrence in an insn.  */
 184 struct lra_insn_reg
 185 {
 186   /* The biggest mode through which the insn refers to the register
 187      occurrence (remember the register can be accessed through a
 188      subreg in the insn).  */
 189   ENUM_BITFIELD(machine_mode) biggest_mode : 16;
 190   /* The type of the corresponding operand which is the register.  */
 191   ENUM_BITFIELD (op_type) type : 8;
 192   /* True if the reg is accessed through a subreg and the subreg is
 193      just a part of the register.  */
 194   unsigned int subreg_p : 1;
 195   /* True if there is an early clobber alternative for this
 196      operand.  */
 197   unsigned int early_clobber : 1;
 198   /* The corresponding regno of the register.  */
 199   int regno;
 200   /* Next reg info of the same insn.  */
 201   struct lra_insn_reg *next;
 202
 203   /* Pool allocation new operator.  */
 204   inline void *operator new (size_t)
 205   {
 206     return pool.allocate ();
 207   }
 208
 209   /* Delete operator utilizing pool allocation.  */
 210   inline void operator delete (void *ptr)
 211   {
 212     pool.remove ((lra_insn_reg *) ptr);
 213   }
 214
 215   /* Memory allocation pool.  */
 216   static pool_allocator<lra_insn_reg> pool;
 217 };
 218
 219 /* Static part (common info for insns with the same ICODE) of LRA
 220    internal insn info. It exists in at most one exemplar for each
 221    non-negative ICODE. There is only one exception. Each asm insn has
 222    own structure.  Warning: if the structure definition is changed,
 223    the initializer for debug_insn_static_data in lra.c should be
 224    changed too.  */
 225 struct lra_static_insn_data
 226 {
 227   /* Static info about each insn operand.  */
 228   struct lra_operand_data *operand;
 229   /* Each duplication refers to the number of the corresponding
 230      operand which is duplicated.  */
 231   int *dup_num;
 232   /* The number of an operand marked as commutative, -1 otherwise.  */
 233   int commutative;
 234   /* Number of operands, duplications, and alternatives of the
 235      insn.  */
 236   char n_operands;
 237   char n_dups;
 238   char n_alternatives;
 239   /* Insns in machine description (or clobbers in asm) may contain
 240      explicit hard regs which are not operands.  The following list
 241      describes such hard registers.  */
 242   struct lra_insn_reg *hard_regs;
 243   /* Array [n_alternatives][n_operand] of static constraint info for
 244      given operand in given alternative.  This info can be changed if
 245      the target reg info is changed.  */
 246   const struct operand_alternative *operand_alternative;
 247 };
 248
 249 /* LRA internal info about an insn (LRA internal insn
 250    representation).  */
 251 struct lra_insn_recog_data
 252 {
 253   /* The insn code.  */
 254   int icode;
 255   /* The alternative should be used for the insn, -1 if invalid, or we
 256      should try to use any alternative, or the insn is a debug
 257      insn.  */
 258   int used_insn_alternative;
 259   /* SP offset before the insn relative to one at the func start.  */
 260   HOST_WIDE_INT sp_offset;
 261   /* The insn itself.  */
 262   rtx_insn *insn;
 263   /* Common data for insns with the same ICODE.  Asm insns (their
 264      ICODE is negative) do not share such structures.  */
 265   struct lra_static_insn_data *insn_static_data;
 266   /* Two arrays of size correspondingly equal to the operand and the
 267      duplication numbers: */
 268   rtx **operand_loc; /* The operand locations, NULL if no operands.  */
 269   rtx **dup_loc; /* The dup locations, NULL if no dups.  */
 270   /* Number of hard registers implicitly used/clobbered in given call
 271      insn.  The value can be NULL or points to array of the hard
 272      register numbers ending with a negative value.  To differ
 273      clobbered and used hard regs, clobbered hard regs are incremented
 274      by FIRST_PSEUDO_REGISTER.  */
 275   int *arg_hard_regs;
 276   /* Cached value of get_preferred_alternatives.  */
 277   alternative_mask preferred_alternatives;
 278   /* The following member value is always NULL for a debug insn.  */
 279   struct lra_insn_reg *regs;
 280 };
 281
 282 typedef struct lra_insn_recog_data *lra_insn_recog_data_t;
 283
 284 /* Whether the clobber is used temporary in LRA.  */
 285 #define LRA_TEMP_CLOBBER_P(x) \
 286   (RTL_FLAG_CHECK1 ("TEMP_CLOBBER_P", (x), CLOBBER)->unchanging)
 287
 288 /* Cost factor for each additional reload and maximal cost reject for
 289    insn reloads.  One might ask about such strange numbers.  Their
 290    values occurred historically from former reload pass.  */
 291 #define LRA_LOSER_COST_FACTOR 6
 292 #define LRA_MAX_REJECT 600
 293
 294 /* Maximum allowed number of assignment pass iterations after the
 295    latest spill pass when any former reload pseudo was spilled.  It is
 296    for preventing LRA cycling in a bug case.  */
 297 #define LRA_MAX_ASSIGNMENT_ITERATION_NUMBER 30
 298
 299 /* The maximal number of inheritance/split passes in LRA.  It should
 300    be more 1 in order to perform caller saves transformations and much
 301    less MAX_CONSTRAINT_ITERATION_NUMBER to prevent LRA to do as many
 302    as permitted constraint passes in some complicated cases.  The
 303    first inheritance/split pass has a biggest impact on generated code
 304    quality.  Each subsequent affects generated code in less degree.
 305    For example, the 3rd pass does not change generated SPEC2000 code
 306    at all on x86-64.  */
 307 #define LRA_MAX_INHERITANCE_PASSES 2
 308
 309 #if LRA_MAX_INHERITANCE_PASSES <= 0 \
 310     || LRA_MAX_INHERITANCE_PASSES >= LRA_MAX_ASSIGNMENT_ITERATION_NUMBER - 8
 311 #error wrong LRA_MAX_INHERITANCE_PASSES value
 312 #endif
 313
 314 /* Analogous macro to the above one but for rematerialization.  */
 315 #define LRA_MAX_REMATERIALIZATION_PASSES 2
 316
 317 #if LRA_MAX_REMATERIALIZATION_PASSES <= 0 \
 318     || LRA_MAX_REMATERIALIZATION_PASSES >= LRA_MAX_ASSIGNMENT_ITERATION_NUMBER - 8
 319 #error wrong LRA_MAX_REMATERIALIZATION_PASSES value
 320 #endif
 321
 322 /* lra.c: */
 323
 324 extern FILE *lra_dump_file;
 325
 326 extern bool lra_reg_spill_p;
 327
 328 extern HARD_REG_SET lra_no_alloc_regs;
 329
 330 extern int lra_insn_recog_data_len;
 331 extern lra_insn_recog_data_t *lra_insn_recog_data;
 332
 333 extern int lra_curr_reload_num;
 334
 335 extern void lra_dump_bitmap_with_title (const char *, bitmap, int);
 336 extern void lra_push_insn (rtx_insn *);
 337 extern void lra_push_insn_by_uid (unsigned int);
 338 extern void lra_push_insn_and_update_insn_regno_info (rtx_insn *);
 339 extern rtx_insn *lra_pop_insn (void);
 340 extern unsigned int lra_insn_stack_length (void);
 341
 342 extern rtx lra_create_new_reg_with_unique_value (machine_mode, rtx,
 343                                                  enum reg_class, const char *);
 344 extern void lra_set_regno_unique_value (int);
 345 extern void lra_invalidate_insn_data (rtx_insn *);
 346 extern void lra_set_insn_deleted (rtx_insn *);
 347 extern void lra_delete_dead_insn (rtx_insn *);
 348 extern void lra_emit_add (rtx, rtx, rtx);
 349 extern void lra_emit_move (rtx, rtx);
 350 extern void lra_update_dups (lra_insn_recog_data_t, signed char *);
 351
 352 extern void lra_process_new_insns (rtx_insn *, rtx_insn *, rtx_insn *,
 353                                    const char *);
 354
 355 extern bool lra_substitute_pseudo (rtx *, int, rtx, bool);
 356 extern bool lra_substitute_pseudo_within_insn (rtx_insn *, int, rtx, bool);
 357
 358 extern lra_insn_recog_data_t lra_set_insn_recog_data (rtx_insn *);
 359 extern lra_insn_recog_data_t lra_update_insn_recog_data (rtx_insn *);
 360 extern void lra_set_used_insn_alternative (rtx_insn *, int);
 361 extern void lra_set_used_insn_alternative_by_uid (int, int);
 362
 363 extern void lra_invalidate_insn_regno_info (rtx_insn *);
 364 extern void lra_update_insn_regno_info (rtx_insn *);
 365 extern struct lra_insn_reg *lra_get_insn_regs (int);
 366
 367 extern void lra_free_copies (void);
 368 extern void lra_create_copy (int, int, int);
 369 extern lra_copy_t lra_get_copy (int);
 370 extern bool lra_former_scratch_p (int);
 371 extern bool lra_former_scratch_operand_p (rtx_insn *, int);
 372 extern void lra_register_new_scratch_op (rtx_insn *, int);
 373
 374 extern int lra_new_regno_start;
 375 extern int lra_constraint_new_regno_start;
 376 extern int lra_bad_spill_regno_start;
 377 extern bitmap_head lra_inheritance_pseudos;
 378 extern bitmap_head lra_split_regs;
 379 extern bitmap_head lra_subreg_reload_pseudos;
 380 extern bitmap_head lra_optional_reload_pseudos;
 381
 382 /* lra-constraints.c: */
 383
 384 extern void lra_init_equiv (void);
 385 extern int lra_constraint_offset (int, machine_mode);
 386
 387 extern int lra_constraint_iter;
 388 extern bool lra_risky_transformations_p;
 389 extern int lra_inheritance_iter;
 390 extern int lra_undo_inheritance_iter;
 391 extern bool lra_constrain_insn (rtx_insn *);
 392 extern bool lra_constraints (bool);
 393 extern void lra_constraints_init (void);
 394 extern void lra_constraints_finish (void);
 395 extern void lra_inheritance (void);
 396 extern bool lra_undo_inheritance (void);
 397
 398 /* lra-lives.c: */
 399
 400 extern int lra_live_max_point;
 401 extern int *lra_point_freq;
 402
 403 extern int lra_hard_reg_usage[FIRST_PSEUDO_REGISTER];
 404
 405 extern int lra_live_range_iter;
 406 extern void lra_create_live_ranges (bool, bool);
 407 extern lra_live_range_t lra_copy_live_range_list (lra_live_range_t);
 408 extern lra_live_range_t lra_merge_live_ranges (lra_live_range_t,
 409                                                lra_live_range_t);
 410 extern bool lra_intersected_live_ranges_p (lra_live_range_t,
 411                                            lra_live_range_t);
 412 extern void lra_print_live_range_list (FILE *, lra_live_range_t);
 413 extern void debug (lra_live_range &ref);
 414 extern void debug (lra_live_range *ptr);
 415 extern void lra_debug_live_range_list (lra_live_range_t);
 416 extern void lra_debug_pseudo_live_ranges (int);
 417 extern void lra_debug_live_ranges (void);
 418 extern void lra_clear_live_ranges (void);
 419 extern void lra_live_ranges_init (void);
 420 extern void lra_live_ranges_finish (void);
 421 extern void lra_setup_reload_pseudo_preferenced_hard_reg (int, int, int);
 422
 423 /* lra-assigns.c: */
 424
 425 extern int lra_assignment_iter;
 426 extern int lra_assignment_iter_after_spill;
 427 extern void lra_setup_reg_renumber (int, int, bool);
 428 extern bool lra_assign (void);
 429
 430
 431 /* lra-coalesce.c: */
 432
 433 extern int lra_coalesce_iter;
 434 extern bool lra_coalesce (void);
 435
 436 /* lra-spills.c:  */
 437
 438 extern bool lra_need_for_spills_p (void);
 439 extern void lra_spill (void);
 440 extern void lra_final_code_change (void);
 441
 442 /* lra-remat.c:  */
 443
 444 extern int lra_rematerialization_iter;
 445 extern bool lra_remat (void);
 446
 447 /* lra-elimination.c: */
 448
 449 extern void lra_debug_elim_table (void);
 450 extern int lra_get_elimination_hard_regno (int);
 451 extern rtx lra_eliminate_regs_1 (rtx_insn *, rtx, machine_mode,
 452                                  bool, bool, HOST_WIDE_INT, bool);
 453 extern void eliminate_regs_in_insn (rtx_insn *insn, bool, bool, HOST_WIDE_INT);
 454 extern void lra_eliminate (bool, bool);
 455
 456 extern void lra_eliminate_reg_if_possible (rtx *);
 457
 458 \f
 459
 460 /* Return the hard register which given pseudo REGNO assigned to.
 461    Negative value means that the register got memory or we don't know
 462    allocation yet.  */
 463 static inline int
 464 lra_get_regno_hard_regno (int regno)
 465 {
 466   resize_reg_info ();
 467   return reg_renumber[regno];
 468 }
 469
 470 /* Change class of pseudo REGNO to NEW_CLASS.  Print info about it
 471    using TITLE.  Output a new line if NL_P.  */
 472 static void inline
 473 lra_change_class (int regno, enum reg_class new_class,
 474                   const char *title, bool nl_p)
 475 {
 476   lra_assert (regno >= FIRST_PSEUDO_REGISTER);
 477   if (lra_dump_file != NULL)
 478     fprintf (lra_dump_file, "%s class %s for r%d",
 479              title, reg_class_names[new_class], regno);
 480   setup_reg_classes (regno, new_class, NO_REGS, new_class);
 481   if (lra_dump_file != NULL && nl_p)
 482     fprintf (lra_dump_file, "\n");
 483 }
 484
 485 /* Update insn operands which are duplication of NOP operand.  The
 486    insn is represented by its LRA internal representation ID.  */
 487 static inline void
 488 lra_update_dup (lra_insn_recog_data_t id, int nop)
 489 {
 490   int i;
 491   struct lra_static_insn_data *static_id = id->insn_static_data;
 492
 493   for (i = 0; i < static_id->n_dups; i++)
 494     if (static_id->dup_num[i] == nop)
 495       *id->dup_loc[i] = *id->operand_loc[nop];
 496 }
 497
 498 /* Process operator duplications in insn with ID.  We do it after the
 499    operands processing.  Generally speaking, we could do this probably
 500    simultaneously with operands processing because a common practice
 501    is to enumerate the operators after their operands.  */
 502 static inline void
 503 lra_update_operator_dups (lra_insn_recog_data_t id)
 504 {
 505   int i;
 506   struct lra_static_insn_data *static_id = id->insn_static_data;
 507
 508   for (i = 0; i < static_id->n_dups; i++)
 509     {
 510       int ndup = static_id->dup_num[i];
 511
 512       if (static_id->operand[ndup].is_operator)
 513         *id->dup_loc[i] = *id->operand_loc[ndup];
 514     }
 515 }
 516
 517 /* Return info about INSN.  Set up the info if it is not done yet.  */
 518 static inline lra_insn_recog_data_t
 519 lra_get_insn_recog_data (rtx_insn *insn)
 520 {
 521   lra_insn_recog_data_t data;
 522   unsigned int uid = INSN_UID (insn);
 523
 524   if (lra_insn_recog_data_len > (int) uid
 525       && (data = lra_insn_recog_data[uid]) != NULL)
 526     {
 527       /* Check that we did not change insn without updating the insn
 528          info.  */
 529       lra_assert (data->insn == insn
 530                   && (INSN_CODE (insn) < 0
 531                       || data->icode == INSN_CODE (insn)));
 532       return data;
 533     }
 534   return lra_set_insn_recog_data (insn);
 535 }
 536
 537 /* Update offset from pseudos with VAL by INCR.  */
 538 static inline void
 539 lra_update_reg_val_offset (int val, int incr)
 540 {
 541   int i;
 542
 543   for (i = FIRST_PSEUDO_REGISTER; i < max_reg_num (); i++)
 544     {
 545       if (lra_reg_info[i].val == val)
 546         lra_reg_info[i].offset += incr;
 547     }
 548 }
 549
 550 /* Return true if register content is equal to VAL with OFFSET.  */
 551 static inline bool
 552 lra_reg_val_equal_p (int regno, int val, int offset)
 553 {
 554   if (lra_reg_info[regno].val == val
 555       && lra_reg_info[regno].offset == offset)
 556     return true;
 557
 558   return false;
 559 }
 560
 561 /* Assign value of register FROM to TO.  */
 562 static inline void
 563 lra_assign_reg_val (int from, int to)
 564 {
 565   lra_reg_info[to].val = lra_reg_info[from].val;
 566   lra_reg_info[to].offset = lra_reg_info[from].offset;
 567 }
 568
 569 #endif /* GCC_LRA_INT_H */