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   /* Alternative enabled for the insn.  NULL for debug insns.  */
 231   bool *alternative_enabled_p;
 232   /* The alternative should be used for the insn, -1 if invalid, or we
 233      should try to use any alternative, or the insn is a debug
 234      insn.  */
 235   int used_insn_alternative;
 236   /* The following member value is always NULL for a debug insn.  */
 237   struct lra_insn_reg *regs;
 238 };
 239
 240 typedef struct lra_insn_recog_data *lra_insn_recog_data_t;
 241
 242 /* Whether the clobber is used temporary in LRA.  */
 243 #define LRA_TEMP_CLOBBER_P(x) \
 244   (RTL_FLAG_CHECK1 ("TEMP_CLOBBER_P", (x), CLOBBER)->unchanging)
 245
 246 /* Cost factor for each additional reload and maximal cost reject for
 247    insn reloads.  One might ask about such strange numbers.  Their
 248    values occurred historically from former reload pass.  */
 249 #define LRA_LOSER_COST_FACTOR 6
 250 #define LRA_MAX_REJECT 600
 251
 252 /* lra.c: */
 253
 254 extern FILE *lra_dump_file;
 255
 256 extern bool lra_reg_spill_p;
 257
 258 extern HARD_REG_SET lra_no_alloc_regs;
 259
 260 extern int lra_insn_recog_data_len;
 261 extern lra_insn_recog_data_t *lra_insn_recog_data;
 262
 263 extern int lra_curr_reload_num;
 264
 265 extern void lra_push_insn (rtx);
 266 extern void lra_push_insn_by_uid (unsigned int);
 267 extern void lra_push_insn_and_update_insn_regno_info (rtx);
 268 extern rtx lra_pop_insn (void);
 269 extern unsigned int lra_insn_stack_length (void);
 270
 271 extern rtx lra_create_new_reg_with_unique_value (enum machine_mode, rtx,
 272                                                  enum reg_class, const char *);
 273 extern void lra_set_regno_unique_value (int);
 274 extern void lra_invalidate_insn_data (rtx);
 275 extern void lra_set_insn_deleted (rtx);
 276 extern void lra_delete_dead_insn (rtx);
 277 extern void lra_emit_add (rtx, rtx, rtx);
 278 extern void lra_emit_move (rtx, rtx);
 279 extern void lra_update_dups (lra_insn_recog_data_t, signed char *);
 280
 281 extern void lra_process_new_insns (rtx, rtx, rtx, const char *);
 282
 283 extern lra_insn_recog_data_t lra_set_insn_recog_data (rtx);
 284 extern lra_insn_recog_data_t lra_update_insn_recog_data (rtx);
 285 extern void lra_set_used_insn_alternative (rtx, int);
 286 extern void lra_set_used_insn_alternative_by_uid (int, int);
 287
 288 extern void lra_invalidate_insn_regno_info (rtx);
 289 extern void lra_update_insn_regno_info (rtx);
 290 extern struct lra_insn_reg *lra_get_insn_regs (int);
 291
 292 extern void lra_free_copies (void);
 293 extern void lra_create_copy (int, int, int);
 294 extern lra_copy_t lra_get_copy (int);
 295 extern bool lra_former_scratch_p (int);
 296 extern bool lra_former_scratch_operand_p (rtx, int);
 297
 298 extern int lra_new_regno_start;
 299 extern int lra_constraint_new_regno_start;
 300 extern bitmap_head lra_inheritance_pseudos;
 301 extern bitmap_head lra_split_regs;
 302 extern bitmap_head lra_optional_reload_pseudos;
 303 extern int lra_constraint_new_insn_uid_start;
 304
 305 /* lra-constraints.c: */
 306
 307 extern int lra_constraint_offset (int, enum machine_mode);
 308
 309 extern int lra_constraint_iter;
 310 extern int lra_constraint_iter_after_spill;
 311 extern bool lra_risky_transformations_p;
 312 extern int lra_inheritance_iter;
 313 extern int lra_undo_inheritance_iter;
 314 extern bool lra_constraints (bool);
 315 extern void lra_constraints_init (void);
 316 extern void lra_constraints_finish (void);
 317 extern void lra_inheritance (void);
 318 extern bool lra_undo_inheritance (void);
 319
 320 /* lra-lives.c: */
 321
 322 extern int lra_live_max_point;
 323 extern int *lra_point_freq;
 324
 325 extern int lra_hard_reg_usage[FIRST_PSEUDO_REGISTER];
 326
 327 extern int lra_live_range_iter;
 328 extern void lra_create_live_ranges (bool);
 329 extern lra_live_range_t lra_copy_live_range_list (lra_live_range_t);
 330 extern lra_live_range_t lra_merge_live_ranges (lra_live_range_t,
 331                                                lra_live_range_t);
 332 extern bool lra_intersected_live_ranges_p (lra_live_range_t,
 333                                            lra_live_range_t);
 334 extern void lra_print_live_range_list (FILE *, lra_live_range_t);
 335 extern void lra_debug_live_range_list (lra_live_range_t);
 336 extern void lra_debug_pseudo_live_ranges (int);
 337 extern void lra_debug_live_ranges (void);
 338 extern void lra_clear_live_ranges (void);
 339 extern void lra_live_ranges_init (void);
 340 extern void lra_live_ranges_finish (void);
 341 extern void lra_setup_reload_pseudo_preferenced_hard_reg (int, int, int);
 342
 343 /* lra-assigns.c: */
 344
 345 extern void lra_setup_reg_renumber (int, int, bool);
 346 extern bool lra_assign (void);
 347
 348
 349 /* lra-coalesce.c: */
 350
 351 extern int lra_coalesce_iter;
 352 extern bool lra_coalesce (void);
 353
 354 /* lra-spills.c:  */
 355
 356 extern bool lra_need_for_spills_p (void);
 357 extern void lra_spill (void);
 358 extern void lra_final_code_change (void);
 359
 360
 361 /* lra-elimination.c: */
 362
 363 extern void lra_debug_elim_table (void);
 364 extern int lra_get_elimination_hard_regno (int);
 365 extern rtx lra_eliminate_regs_1 (rtx, enum machine_mode, bool, bool, bool);
 366 extern void lra_eliminate (bool);
 367
 368 extern void lra_eliminate_reg_if_possible (rtx *);
 369
 370 \f
 371
 372 /* Update insn operands which are duplication of NOP operand.  The
 373    insn is represented by its LRA internal representation ID.  */
 374 static inline void
 375 lra_update_dup (lra_insn_recog_data_t id, int nop)
 376 {
 377   int i;
 378   struct lra_static_insn_data *static_id = id->insn_static_data;
 379
 380   for (i = 0; i < static_id->n_dups; i++)
 381     if (static_id->dup_num[i] == nop)
 382       *id->dup_loc[i] = *id->operand_loc[nop];
 383 }
 384
 385 /* Process operator duplications in insn with ID.  We do it after the
 386    operands processing.  Generally speaking, we could do this probably
 387    simultaneously with operands processing because a common practice
 388    is to enumerate the operators after their operands.  */
 389 static inline void
 390 lra_update_operator_dups (lra_insn_recog_data_t id)
 391 {
 392   int i;
 393   struct lra_static_insn_data *static_id = id->insn_static_data;
 394
 395   for (i = 0; i < static_id->n_dups; i++)
 396     {
 397       int ndup = static_id->dup_num[i];
 398
 399       if (static_id->operand[ndup].is_operator)
 400         *id->dup_loc[i] = *id->operand_loc[ndup];
 401     }
 402 }
 403
 404 /* Return info about INSN.  Set up the info if it is not done yet.  */
 405 static inline lra_insn_recog_data_t
 406 lra_get_insn_recog_data (rtx insn)
 407 {
 408   lra_insn_recog_data_t data;
 409   unsigned int uid = INSN_UID (insn);
 410
 411   if (lra_insn_recog_data_len > (int) uid
 412       && (data = lra_insn_recog_data[uid]) != NULL)
 413     {
 414       /* Check that we did not change insn without updating the insn
 415          info.  */
 416       lra_assert (data->insn == insn
 417                   && (INSN_CODE (insn) < 0
 418                       || data->icode == INSN_CODE (insn)));
 419       return data;
 420     }
 421   return lra_set_insn_recog_data (insn);
 422 }
 423
 424 \f
 425
 426 struct target_lra_int
 427 {
 428   /* Map INSN_UID -> the operand alternative data (NULL if unknown).
 429      We assume that this data is valid until register info is changed
 430      because classes in the data can be changed.  */
 431   struct operand_alternative *x_op_alt_data[LAST_INSN_CODE];
 432 };
 433
 434 extern struct target_lra_int default_target_lra_int;
 435 #if SWITCHABLE_TARGET
 436 extern struct target_lra_int *this_target_lra_int;
 437 #else
 438 #define this_target_lra_int (&default_target_lra_int)
 439 #endif
 440
 441 #define op_alt_data (this_target_lra_int->x_op_alt_data)