old-autovect-branch/gcc/tree-flow.h

   1 /* Data and Control Flow Analysis for Trees.
   2    Copyright (C) 2001, 2003, 2004, 2005 Free Software Foundation, Inc.
   3    Contributed by Diego Novillo <dnovillo@redhat.com>
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 #ifndef _TREE_FLOW_H
  23 #define _TREE_FLOW_H 1
  24
  25 #include "bitmap.h"
  26 #include "hard-reg-set.h"
  27 #include "basic-block.h"
  28 #include "hashtab.h"
  29 #include "tree-gimple.h"
  30 #include "tree-ssa-operands.h"
  31 #include "cgraph.h"
  32 #include "ipa-reference.h"
  33
  34 /* Forward declare structures for the garbage collector GTY markers.  */
  35 #ifndef GCC_BASIC_BLOCK_H
  36 struct edge_def;
  37 typedef struct edge_def *edge;
  38 struct basic_block_def;
  39 typedef struct basic_block_def *basic_block;
  40 #endif
  41
  42 /* True if the code is in ssa form.  */
  43 extern bool in_ssa_p;
  44
  45 typedef struct
  46 {
  47   htab_t htab;
  48   PTR *slot;
  49   PTR *limit;
  50 } htab_iterator;
  51
  52 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
  53    storing each element in RESULT, which is of type TYPE.  */
  54 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
  55   for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
  56         !end_htab_p (&(ITER)); \
  57         RESULT = (TYPE) next_htab_element (&(ITER)))
  58
  59 /*---------------------------------------------------------------------------
  60                       Attributes for SSA_NAMEs.
  61
  62   NOTE: These structures are stored in struct tree_ssa_name
  63   but are only used by the tree optimizers, so it makes better sense
  64   to declare them here to avoid recompiling unrelated files when
  65   making changes.
  66 ---------------------------------------------------------------------------*/
  67
  68 /* Aliasing information for SSA_NAMEs representing pointer variables.  */
  69 struct ptr_info_def GTY(())
  70 {
  71   /* Nonzero if points-to analysis couldn't determine where this pointer
  72      is pointing to.  */
  73   unsigned int pt_anything : 1;
  74
  75   /* Nonzero if the value of this pointer escapes the current function.  */
  76   unsigned int value_escapes_p : 1;
  77
  78   /* Nonzero if this pointer is dereferenced.  */
  79   unsigned int is_dereferenced : 1;
  80
  81   /* Nonzero if this pointer points to a global variable.  */
  82   unsigned int pt_global_mem : 1;
  83
  84   /* Nonzero if this pointer points to NULL.  */
  85   unsigned int pt_null : 1;
  86
  87   /* Set of variables that this pointer may point to.  */
  88   bitmap pt_vars;
  89
  90   /* If this pointer has been dereferenced, and points-to information is
  91      more precise than type-based aliasing, indirect references to this
  92      pointer will be represented by this memory tag, instead of the type
  93      tag computed by TBAA.  */
  94   tree name_mem_tag;
  95
  96   /*  The alignment of a pointer p is n if "(p - offset) mod n == 0". */
  97   struct alignment_d
  98   {
  99     unsigned int n;
 100     unsigned int offset;
 101   } alignment;
 102
 103 };
 104
 105
 106 /*---------------------------------------------------------------------------
 107                    Tree annotations stored in tree_common.ann
 108 ---------------------------------------------------------------------------*/
 109 enum tree_ann_type { TREE_ANN_COMMON, VAR_ANN, STMT_ANN };
 110
 111 struct tree_ann_common_d GTY(())
 112 {
 113   /* Annotation type.  */
 114   enum tree_ann_type type;
 115
 116  /* Auxiliary info specific to a pass.  At all times, this
 117     should either point to valid data or be NULL.  */
 118   PTR GTY ((skip (""))) aux;
 119
 120   /* The value handle for this expression.  Used by GVN-PRE.  */
 121   tree GTY((skip)) value_handle;
 122 };
 123
 124 /* It is advantageous to avoid things like life analysis for variables which
 125    do not need PHI nodes.  This enum describes whether or not a particular
 126    variable may need a PHI node.  */
 127
 128 enum need_phi_state {
 129   /* This is the default.  If we are still in this state after finding
 130      all the definition and use sites, then we will assume the variable
 131      needs PHI nodes.  This is probably an overly conservative assumption.  */
 132   NEED_PHI_STATE_UNKNOWN,
 133
 134   /* This state indicates that we have seen one or more sets of the
 135      variable in a single basic block and that the sets dominate all
 136      uses seen so far.  If after finding all definition and use sites
 137      we are still in this state, then the variable does not need any
 138      PHI nodes.  */
 139   NEED_PHI_STATE_NO,
 140
 141   /* This state indicates that we have either seen multiple definitions of
 142      the variable in multiple blocks, or that we encountered a use in a
 143      block that was not dominated by the block containing the set(s) of
 144      this variable.  This variable is assumed to need PHI nodes.  */
 145   NEED_PHI_STATE_MAYBE
 146 };
 147
 148 struct subvar;
 149 typedef struct subvar *subvar_t;
 150
 151 /* This structure represents a fake sub-variable for a structure field.  */
 152 struct subvar GTY(())
 153 {
 154   /* Fake variable.  */
 155   tree var;
 156
 157   /* Offset inside structure.  */
 158   unsigned HOST_WIDE_INT offset;
 159
 160   /* Size of the field.  */
 161   unsigned HOST_WIDE_INT size;
 162
 163   /* Next subvar for this structure.  */
 164   subvar_t next;
 165 };
 166
 167 struct var_ann_d GTY(())
 168 {
 169   struct tree_ann_common_d common;
 170
 171   /* Used by the out of SSA pass to determine whether this variable has
 172      been seen yet or not.  */
 173   unsigned out_of_ssa_tag : 1;
 174
 175   /* Used when building root_var structures in tree_ssa_live.[ch].  */
 176   unsigned root_var_processed : 1;
 177
 178   /* Nonzero if this variable is an alias tag that represents references to
 179      other variables (i.e., this variable appears in the MAY_ALIASES array
 180      of other variables).  */
 181   unsigned is_alias_tag : 1;
 182
 183   /* Nonzero if this variable was used after SSA optimizations were
 184      applied.  We set this when translating out of SSA form.  */
 185   unsigned used : 1;
 186
 187   /* This field indicates whether or not the variable may need PHI nodes.
 188      See the enum's definition for more detailed information about the
 189      states.  */
 190   ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
 191
 192   /* Used during operand processing to determine if this variable is already
 193      in the vuse list.  */
 194   unsigned in_vuse_list : 1;
 195
 196   /* Used during operand processing to determine if this variable is already
 197      in the v_may_def list.  */
 198   unsigned in_v_may_def_list : 1;
 199
 200   /* An artificial variable representing the memory location pointed-to by
 201      all the pointers that TBAA (type-based alias analysis) considers
 202      to be aliased.  If the variable is not a pointer or if it is never
 203      dereferenced, this must be NULL.  */
 204   tree type_mem_tag;
 205
 206   /* Variables that may alias this variable.  */
 207   varray_type may_aliases;
 208
 209   /* Used when going out of SSA form to indicate which partition this
 210      variable represents storage for.  */
 211   unsigned partition;
 212
 213   /* Used by the root-var object in tree-ssa-live.[ch].  */
 214   unsigned root_index;
 215
 216   /* During into-ssa and the dominator optimizer, this field holds the
 217      current version of this variable (an SSA_NAME).  */
 218   tree current_def;
 219
 220   /* Pointer to the structure that contains the sets of global
 221      variables modified by function calls.  This field is only used
 222      for FUNCTION_DECLs.  */
 223   ipa_reference_vars_info_t GTY ((skip)) reference_vars_info;
 224
 225   /* If this variable is a structure, this fields holds a list of
 226      symbols representing each of the fields of the structure.  */
 227   subvar_t subvars;
 228 };
 229
 230
 231 typedef struct immediate_use_iterator_d
 232 {
 233   ssa_use_operand_t *imm_use;
 234   ssa_use_operand_t *end_p;
 235   ssa_use_operand_t iter_node;
 236 } imm_use_iterator;
 237
 238
 239 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 240    modifying stmts will cause this iterator to malfunction.  */
 241
 242 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)                       \
 243   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 244        !end_readonly_imm_use_p (&(ITER));                       \
 245        (DEST) = next_readonly_imm_use (&(ITER)))
 246
 247
 248 #define FOR_EACH_IMM_USE_SAFE(DEST, ITER, SSAVAR)               \
 249   for ((DEST) = first_safe_imm_use (&(ITER), (SSAVAR));         \
 250        !end_safe_imm_use_p (&(ITER));                           \
 251        (DEST) = next_safe_imm_use (&(ITER)))
 252
 253 #define BREAK_FROM_SAFE_IMM_USE(ITER)                           \
 254    {                                                            \
 255      end_safe_imm_use_traverse (&(ITER));                       \
 256      break;                                                     \
 257    }
 258
 259 struct stmt_ann_d GTY(())
 260 {
 261   struct tree_ann_common_d common;
 262
 263   /* Nonzero if the statement has been modified (meaning that the operands
 264      need to be scanned again).  */
 265   unsigned modified : 1;
 266
 267   /* Nonzero if the statement makes aliased loads.  */
 268   unsigned makes_aliased_loads : 1;
 269
 270   /* Nonzero if the statement makes aliased stores.  */
 271   unsigned makes_aliased_stores : 1;
 272
 273   /* Nonzero if the statement makes references to volatile storage.  */
 274   unsigned has_volatile_ops : 1;
 275
 276   /* Nonzero if the statement makes a function call that may clobber global
 277      and local addressable variables.  */
 278   unsigned makes_clobbering_call : 1;
 279
 280   /* Basic block that contains this statement.  */
 281   basic_block bb;
 282
 283   /* Operand cache for stmt.  */
 284   struct stmt_operands_d GTY ((skip (""))) operands;
 285
 286   /* Set of variables that have had their address taken in the statement.  */
 287   bitmap addresses_taken;
 288
 289   /* Unique identifier for this statement.  These ID's are to be created
 290      by each pass on an as-needed basis in any order convenient for the
 291      pass which needs statement UIDs.  */
 292   unsigned int uid;
 293
 294   /* Linked list of histograms for value-based profiling.  This is really a
 295      struct histogram_value*.  We use void* to avoid having to export that
 296      everywhere, and to avoid having to put it in GC memory.  */
 297
 298   void * GTY ((skip (""))) histograms;
 299 };
 300
 301 union tree_ann_d GTY((desc ("ann_type ((tree_ann_t)&%h)")))
 302 {
 303   struct tree_ann_common_d GTY((tag ("TREE_ANN_COMMON"))) common;
 304   struct var_ann_d GTY((tag ("VAR_ANN"))) decl;
 305   struct stmt_ann_d GTY((tag ("STMT_ANN"))) stmt;
 306 };
 307
 308 extern GTY(()) VEC(tree,gc) *modified_noreturn_calls;
 309
 310 typedef union tree_ann_d *tree_ann_t;
 311 typedef struct var_ann_d *var_ann_t;
 312 typedef struct stmt_ann_d *stmt_ann_t;
 313
 314 static inline tree_ann_t tree_ann (tree);
 315 static inline tree_ann_t get_tree_ann (tree);
 316 static inline var_ann_t var_ann (tree);
 317 static inline var_ann_t get_var_ann (tree);
 318 static inline stmt_ann_t stmt_ann (tree);
 319 static inline stmt_ann_t get_stmt_ann (tree);
 320 static inline enum tree_ann_type ann_type (tree_ann_t);
 321 static inline basic_block bb_for_stmt (tree);
 322 extern void set_bb_for_stmt (tree, basic_block);
 323 static inline bool noreturn_call_p (tree);
 324 static inline void update_stmt (tree);
 325 static inline bool stmt_modified_p (tree);
 326 static inline varray_type may_aliases (tree);
 327 static inline int get_lineno (tree);
 328 static inline const char *get_filename (tree);
 329 static inline bool is_exec_stmt (tree);
 330 static inline bool is_label_stmt (tree);
 331 static inline bitmap addresses_taken (tree);
 332
 333 /*---------------------------------------------------------------------------
 334                   Structure representing predictions in tree level.
 335 ---------------------------------------------------------------------------*/
 336 struct edge_prediction GTY((chain_next ("%h.ep_next")))
 337 {
 338   struct edge_prediction *ep_next;
 339   edge ep_edge;
 340   enum br_predictor ep_predictor;
 341   int ep_probability;
 342 };
 343
 344 /* Accessors for basic block annotations.  */
 345 static inline tree phi_nodes (basic_block);
 346 static inline void set_phi_nodes (basic_block, tree);
 347
 348 /*---------------------------------------------------------------------------
 349                               Global declarations
 350 ---------------------------------------------------------------------------*/
 351 struct int_tree_map GTY(())
 352 {
 353
 354   unsigned int uid;
 355   tree to;
 356 };
 357
 358 extern unsigned int int_tree_map_hash (const void *);
 359 extern int int_tree_map_eq (const void *, const void *);
 360
 361 typedef struct
 362 {
 363   htab_iterator hti;
 364 } referenced_var_iterator;
 365
 366
 367 /* This macro loops over all the referenced vars, one at a time, putting the
 368    current var in VAR.  Note:  You are not allowed to add referenced variables
 369    to the hashtable while using this macro.  Doing so may cause it to behave
 370    erratically.  */
 371
 372 #define FOR_EACH_REFERENCED_VAR(VAR, ITER) \
 373   for ((VAR) = first_referenced_var (&(ITER)); \
 374        !end_referenced_vars_p (&(ITER)); \
 375        (VAR) = next_referenced_var (&(ITER)))
 376
 377
 378 typedef struct
 379 {
 380   int i;
 381 } safe_referenced_var_iterator;
 382
 383 /* This macro loops over all the referenced vars, one at a time, putting the
 384    current var in VAR.  You are allowed to add referenced variables during the
 385    execution of this macro, however, the macro will not iterate over them.  It
 386    requires a temporary vector of trees, VEC, whose lifetime is controlled by
 387    the caller.  The purpose of the vector is to temporarily store the
 388    referenced_variables hashtable so that adding referenced variables does not
 389    affect the hashtable.  */
 390
 391 #define FOR_EACH_REFERENCED_VAR_SAFE(VAR, VEC, ITER) \
 392   for ((ITER).i = 0, fill_referenced_var_vec (&(VEC)); \
 393        VEC_iterate (tree, (VEC), (ITER).i, (VAR)); \
 394        (ITER).i++)
 395
 396 /* Array of all variables referenced in the function.  */
 397 extern GTY((param_is (struct int_tree_map))) htab_t referenced_vars;
 398
 399 /* Default defs for undefined symbols. */
 400 extern GTY((param_is (struct int_tree_map))) htab_t default_defs;
 401
 402 extern tree referenced_var_lookup (unsigned int);
 403 extern tree referenced_var_lookup_if_exists (unsigned int);
 404 #define num_referenced_vars htab_elements (referenced_vars)
 405 #define referenced_var(i) referenced_var_lookup (i)
 406
 407 /* Array of all SSA_NAMEs used in the function.  */
 408 extern GTY(()) VEC(tree,gc) *ssa_names;
 409
 410 #define num_ssa_names (VEC_length (tree, ssa_names))
 411 #define ssa_name(i) (VEC_index (tree, ssa_names, (i)))
 412
 413 /* Artificial variable used to model the effects of function calls.  */
 414 extern GTY(()) tree global_var;
 415
 416 /* Call clobbered variables in the function.  If bit I is set, then
 417    REFERENCED_VARS (I) is call-clobbered.  */
 418 extern bitmap call_clobbered_vars;
 419
 420 /* Addressable variables in the function.  If bit I is set, then
 421    REFERENCED_VARS (I) has had its address taken.  */
 422 extern bitmap addressable_vars;
 423
 424 /* 'true' after aliases have been computed (see compute_may_aliases).  */
 425 extern bool aliases_computed_p;
 426
 427 /* Macros for showing usage statistics.  */
 428 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 429                   ? (x)                                 \
 430                   : ((x) < 1024*1024*10                 \
 431                      ? (x) / 1024                       \
 432                      : (x) / (1024*1024))))
 433
 434 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 435
 436 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 437
 438 /*---------------------------------------------------------------------------
 439                               Block iterators
 440 ---------------------------------------------------------------------------*/
 441
 442 typedef struct {
 443   tree_stmt_iterator tsi;
 444   basic_block bb;
 445 } block_stmt_iterator;
 446
 447 static inline block_stmt_iterator bsi_start (basic_block);
 448 static inline block_stmt_iterator bsi_last (basic_block);
 449 static inline block_stmt_iterator bsi_after_labels (basic_block);
 450 block_stmt_iterator bsi_for_stmt (tree);
 451 static inline bool bsi_end_p (block_stmt_iterator);
 452 static inline void bsi_next (block_stmt_iterator *);
 453 static inline void bsi_prev (block_stmt_iterator *);
 454 static inline tree bsi_stmt (block_stmt_iterator);
 455 static inline tree * bsi_stmt_ptr (block_stmt_iterator);
 456
 457 extern void bsi_remove (block_stmt_iterator *);
 458 extern void bsi_move_before (block_stmt_iterator *, block_stmt_iterator *);
 459 extern void bsi_move_after (block_stmt_iterator *, block_stmt_iterator *);
 460 extern void bsi_move_to_bb_end (block_stmt_iterator *, basic_block);
 461
 462 enum bsi_iterator_update
 463 {
 464   /* Note that these are intentionally in the same order as TSI_FOO.  They
 465      mean exactly the same as their TSI_* counterparts.  */
 466   BSI_NEW_STMT,
 467   BSI_SAME_STMT,
 468   BSI_CHAIN_START,
 469   BSI_CHAIN_END,
 470   BSI_CONTINUE_LINKING
 471 };
 472
 473 extern void bsi_insert_before (block_stmt_iterator *, tree,
 474                                enum bsi_iterator_update);
 475 extern void bsi_insert_after (block_stmt_iterator *, tree,
 476                               enum bsi_iterator_update);
 477
 478 extern void bsi_replace (const block_stmt_iterator *, tree, bool);
 479
 480 /*---------------------------------------------------------------------------
 481                               Function prototypes
 482 ---------------------------------------------------------------------------*/
 483 /* In tree-cfg.c  */
 484
 485 /* Location to track pending stmt for edge insertion.  */
 486 #define PENDING_STMT(e) ((e)->insns.t)
 487
 488 extern void delete_tree_cfg_annotations (void);
 489 extern void disband_implicit_edges (void);
 490 extern bool stmt_ends_bb_p (tree);
 491 extern bool is_ctrl_stmt (tree);
 492 extern bool is_ctrl_altering_stmt (tree);
 493 extern bool computed_goto_p (tree);
 494 extern bool simple_goto_p (tree);
 495 extern void tree_dump_bb (basic_block, FILE *, int);
 496 extern void debug_tree_bb (basic_block);
 497 extern basic_block debug_tree_bb_n (int);
 498 extern void dump_tree_cfg (FILE *, int);
 499 extern void debug_tree_cfg (int);
 500 extern void dump_cfg_stats (FILE *);
 501 extern void debug_cfg_stats (void);
 502 extern void debug_loop_ir (void);
 503 extern void print_loop_ir (FILE *);
 504 extern void cleanup_dead_labels (void);
 505 extern void group_case_labels (void);
 506 extern tree first_stmt (basic_block);
 507 extern tree last_stmt (basic_block);
 508 extern tree *last_stmt_ptr (basic_block);
 509 extern tree last_and_only_stmt (basic_block);
 510 extern edge find_taken_edge (basic_block, tree);
 511 extern basic_block label_to_block_fn (struct function *, tree);
 512 #define label_to_block(t) (label_to_block_fn (cfun, t))
 513 extern void bsi_insert_on_edge (edge, tree);
 514 extern basic_block bsi_insert_on_edge_immediate (edge, tree);
 515 extern void bsi_commit_one_edge_insert (edge, basic_block *);
 516 extern void bsi_commit_edge_inserts (void);
 517 extern void notice_special_calls (tree);
 518 extern void clear_special_calls (void);
 519 extern void verify_stmts (void);
 520 extern tree tree_block_label (basic_block);
 521 extern bool tree_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 522                                         basic_block *);
 523 extern void add_phi_args_after_copy_bb (basic_block);
 524 extern void add_phi_args_after_copy (basic_block *, unsigned);
 525 extern bool tree_purge_dead_eh_edges (basic_block);
 526 extern bool tree_purge_all_dead_eh_edges (bitmap);
 527 extern tree gimplify_val (block_stmt_iterator *, tree, tree);
 528 extern tree gimplify_build1 (block_stmt_iterator *, enum tree_code,
 529                              tree, tree);
 530 extern tree gimplify_build2 (block_stmt_iterator *, enum tree_code,
 531                              tree, tree, tree);
 532 extern tree gimplify_build3 (block_stmt_iterator *, enum tree_code,
 533                              tree, tree, tree, tree);
 534 extern void init_empty_tree_cfg (void);
 535 extern void fold_cond_expr_cond (void);
 536 extern void replace_uses_by (tree, tree);
 537 extern void start_recording_case_labels (void);
 538 extern void end_recording_case_labels (void);
 539
 540 /* In tree-cfgcleanup.c  */
 541 extern bool cleanup_tree_cfg (void);
 542 extern void cleanup_tree_cfg_loop (void);
 543
 544 /* In tree-pretty-print.c.  */
 545 extern void dump_generic_bb (FILE *, basic_block, int, int);
 546
 547 /* In tree-dfa.c  */
 548 extern var_ann_t create_var_ann (tree);
 549 extern stmt_ann_t create_stmt_ann (tree);
 550 extern tree_ann_t create_tree_ann (tree);
 551 extern void dump_dfa_stats (FILE *);
 552 extern void debug_dfa_stats (void);
 553 extern void debug_referenced_vars (void);
 554 extern void dump_referenced_vars (FILE *);
 555 extern void dump_variable (FILE *, tree);
 556 extern void debug_variable (tree);
 557 extern void dump_subvars_for (FILE *, tree);
 558 extern void debug_subvars_for (tree);
 559 extern tree get_virtual_var (tree);
 560 extern void add_referenced_tmp_var (tree);
 561 extern void mark_new_vars_to_rename (tree);
 562 extern void find_new_referenced_vars (tree *);
 563
 564 extern tree make_rename_temp (tree, const char *);
 565 extern void set_default_def (tree, tree);
 566 extern tree default_def (tree);
 567 extern tree default_def_fn (struct function *, tree);
 568
 569 /* In tree-phinodes.c  */
 570 extern void reserve_phi_args_for_new_edge (basic_block);
 571 extern tree create_phi_node (tree, basic_block);
 572 extern void add_phi_arg (tree, tree, edge);
 573 extern void remove_phi_args (edge);
 574 extern void remove_phi_node (tree, tree);
 575 extern tree phi_reverse (tree);
 576
 577 /* In gimple-low.c  */
 578 extern void record_vars (tree);
 579 extern bool block_may_fallthru (tree block);
 580
 581 /* In tree-ssa-alias.c  */
 582 extern void dump_may_aliases_for (FILE *, tree);
 583 extern void debug_may_aliases_for (tree);
 584 extern void dump_alias_info (FILE *);
 585 extern void debug_alias_info (void);
 586 extern void dump_points_to_info (FILE *);
 587 extern void debug_points_to_info (void);
 588 extern void dump_points_to_info_for (FILE *, tree);
 589 extern void debug_points_to_info_for (tree);
 590 extern bool may_be_aliased (tree);
 591 extern bool is_aliased_with (tree, tree);
 592 extern struct ptr_info_def *get_ptr_info (tree);
 593 extern void add_type_alias (tree, tree);
 594 extern void new_type_alias (tree, tree);
 595 extern void count_uses_and_derefs (tree, tree, unsigned *, unsigned *, bool *);
 596 static inline subvar_t get_subvars_for_var (tree);
 597 static inline tree get_subvar_at (tree, unsigned HOST_WIDE_INT);
 598 static inline bool ref_contains_array_ref (tree);
 599 static inline bool array_ref_contains_indirect_ref (tree);
 600 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
 601                                      HOST_WIDE_INT *, HOST_WIDE_INT *);
 602 static inline bool var_can_have_subvars (tree);
 603 static inline bool overlap_subvar (unsigned HOST_WIDE_INT,
 604                                    unsigned HOST_WIDE_INT,
 605                                    subvar_t, bool *);
 606
 607 /* Call-back function for walk_use_def_chains().  At each reaching
 608    definition, a function with this prototype is called.  */
 609 typedef bool (*walk_use_def_chains_fn) (tree, tree, void *);
 610
 611
 612 /* In tree-ssa.c  */
 613 extern void init_tree_ssa (void);
 614 extern edge ssa_redirect_edge (edge, basic_block);
 615 extern void flush_pending_stmts (edge);
 616 extern bool tree_ssa_useless_type_conversion (tree);
 617 extern bool tree_ssa_useless_type_conversion_1 (tree, tree);
 618 extern void verify_ssa (bool);
 619 extern void delete_tree_ssa (void);
 620 extern void register_new_def (tree, VEC(tree,heap) **);
 621 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 622 extern bool stmt_references_memory_p (tree);
 623 extern void replace_immediate_uses (tree, tree);
 624
 625 /* In tree-into-ssa.c  */
 626 void update_ssa (unsigned);
 627 void delete_update_ssa (void);
 628 void register_new_name_mapping (tree, tree);
 629 tree create_new_def_for (tree, tree, def_operand_p);
 630 bool need_ssa_update_p (void);
 631 bool name_registered_for_update_p (tree);
 632 bitmap ssa_names_to_replace (void);
 633 void release_ssa_name_after_update_ssa (tree name);
 634 void compute_global_livein (bitmap, bitmap);
 635 tree duplicate_ssa_name (tree, tree);
 636 void mark_sym_for_renaming (tree);
 637 void mark_set_for_renaming (bitmap);
 638 tree get_current_def (tree);
 639 void set_current_def (tree, tree);
 640
 641 /* In tree-ssa-ccp.c  */
 642 bool fold_stmt (tree *);
 643 bool fold_stmt_inplace (tree);
 644 tree widen_bitfield (tree, tree, tree);
 645
 646 /* In tree-vrp.c  */
 647 tree vrp_evaluate_conditional (tree, bool);
 648 void simplify_stmt_using_ranges (tree);
 649
 650 /* In tree-ssa-dom.c  */
 651 extern void dump_dominator_optimization_stats (FILE *);
 652 extern void debug_dominator_optimization_stats (void);
 653 int loop_depth_of_name (tree);
 654
 655 /* In tree-ssa-copy.c  */
 656 extern void merge_alias_info (tree, tree);
 657 extern void propagate_value (use_operand_p, tree);
 658 extern void propagate_tree_value (tree *, tree);
 659 extern void replace_exp (use_operand_p, tree);
 660 extern bool may_propagate_copy (tree, tree);
 661 extern bool may_propagate_copy_into_asm (tree);
 662
 663 /* Description of number of iterations of a loop.  All the expressions inside
 664    the structure can be evaluated at the end of the loop's preheader
 665    (and due to ssa form, also anywhere inside the body of the loop).  */
 666
 667 struct tree_niter_desc
 668 {
 669   tree assumptions;     /* The boolean expression.  If this expression evaluates
 670                            to false, then the other fields in this structure
 671                            should not be used; there is no guarantee that they
 672                            will be correct.  */
 673   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 674                            the loop will exit in the first iteration (i.e.
 675                            its latch will not be executed), even if the niter
 676                            field says otherwise.  */
 677   tree niter;           /* The expression giving the number of iterations of
 678                            a loop (provided that assumptions == true and
 679                            may_be_zero == false), more precisely the number
 680                            of executions of the latch of the loop.  */
 681   tree additional_info; /* The boolean expression.  Sometimes we use additional
 682                            knowledge to simplify the other expressions
 683                            contained in this structure (for example the
 684                            knowledge about value ranges of operands on entry to
 685                            the loop).  If this is a case, conjunction of such
 686                            condition is stored in this field, so that we do not
 687                            lose the information: for example if may_be_zero
 688                            is (n <= 0) and niter is (unsigned) n, we know
 689                            that the number of iterations is at most
 690                            MAX_SIGNED_INT.  However if the (n <= 0) assumption
 691                            is eliminated (by looking at the guard on entry of
 692                            the loop), then the information would be lost.  */
 693 };
 694
 695 /* In tree-vectorizer.c */
 696 void vectorize_loops (struct loops *);
 697
 698 /* In tree-ssa-phiopt.c */
 699 bool empty_block_p (basic_block);
 700
 701 /* In tree-ssa-loop*.c  */
 702
 703 void tree_ssa_lim (struct loops *);
 704 void tree_ssa_unswitch_loops (struct loops *);
 705 void canonicalize_induction_variables (struct loops *);
 706 void tree_unroll_loops_completely (struct loops *, bool);
 707 void remove_empty_loops (struct loops *);
 708 void tree_ssa_iv_optimize (struct loops *);
 709
 710 bool number_of_iterations_exit (struct loop *, edge,
 711                                 struct tree_niter_desc *niter, bool);
 712 tree find_loop_niter (struct loop *, edge *);
 713 tree loop_niter_by_eval (struct loop *, edge);
 714 tree find_loop_niter_by_eval (struct loop *, edge *);
 715 void estimate_numbers_of_iterations (struct loops *);
 716 bool scev_probably_wraps_p (tree, tree, tree, tree, struct loop *, bool *,
 717                             bool *);
 718 tree convert_step (struct loop *, tree, tree, tree, tree);
 719 void free_numbers_of_iterations_estimates (struct loops *);
 720 void free_numbers_of_iterations_estimates_loop (struct loop *);
 721 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 722 void verify_loop_closed_ssa (void);
 723 void loop_commit_inserts (void);
 724 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 725 void create_iv (tree, tree, tree, struct loop *, block_stmt_iterator *, bool,
 726                 tree *, tree *);
 727 void split_loop_exit_edge (edge);
 728 void compute_phi_arg_on_exit (edge, tree, tree);
 729 unsigned force_expr_to_var_cost (tree);
 730 basic_block bsi_insert_on_edge_immediate_loop (edge, tree);
 731 void empty_latch_block (struct loops *);
 732 void standard_iv_increment_position (struct loop *, block_stmt_iterator *,
 733                                      bool *);
 734 basic_block ip_end_pos (struct loop *);
 735 basic_block ip_normal_pos (struct loop *);
 736 bool tree_duplicate_loop_to_header_edge (struct loop *, edge, struct loops *,
 737                                          unsigned int, sbitmap,
 738                                          edge, edge *,
 739                                          unsigned int *, int);
 740 struct loop *tree_ssa_loop_version (struct loops *, struct loop *, tree,
 741                                     basic_block *);
 742 tree expand_simple_operations (tree);
 743 void substitute_in_loop_info (struct loop *, tree, tree);
 744 edge single_dom_exit (struct loop *);
 745
 746 /* In tree-ssa-loop-im.c  */
 747 /* The possibilities of statement movement.  */
 748
 749 enum move_pos
 750   {
 751     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 752     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 753                                    become executed -- memory accesses, ... */
 754     MOVE_POSSIBLE               /* Unlimited movement.  */
 755   };
 756 extern enum move_pos movement_possibility (tree);
 757
 758 /* In tree-flow-inline.h  */
 759 static inline bool is_call_clobbered (tree);
 760 static inline void mark_call_clobbered (tree);
 761 static inline void set_is_used (tree);
 762 static inline bool unmodifiable_var_p (tree);
 763
 764 /* In tree-eh.c  */
 765 extern void make_eh_edges (tree);
 766 extern bool tree_could_trap_p (tree);
 767 extern bool tree_could_throw_p (tree);
 768 extern bool tree_can_throw_internal (tree);
 769 extern bool tree_can_throw_external (tree);
 770 extern int lookup_stmt_eh_region (tree);
 771 extern void add_stmt_to_eh_region (tree, int);
 772 extern bool remove_stmt_from_eh_region (tree);
 773 extern bool maybe_clean_or_replace_eh_stmt (tree, tree);
 774
 775 /* In tree-ssa-pre.c  */
 776 void add_to_value (tree, tree);
 777 void debug_value_expressions (tree);
 778 void print_value_expressions (FILE *, tree);
 779
 780
 781 /* In tree-vn.c  */
 782 bool expressions_equal_p (tree, tree);
 783 tree get_value_handle (tree);
 784 hashval_t vn_compute (tree, hashval_t, tree);
 785 tree vn_lookup_or_add (tree, tree);
 786 void vn_add (tree, tree, tree);
 787 tree vn_lookup (tree, tree);
 788 void vn_init (void);
 789 void vn_delete (void);
 790
 791 /* In tree-ssa-sink.c  */
 792 bool is_hidden_global_store (tree);
 793
 794 /* In tree-sra.c  */
 795 void insert_edge_copies (tree, basic_block);
 796 void sra_insert_before (block_stmt_iterator *, tree);
 797 void sra_insert_after (block_stmt_iterator *, tree);
 798 void sra_init_cache (void);
 799 bool sra_type_can_be_decomposed_p (tree);
 800
 801 /* In tree-loop-linear.c  */
 802 extern void linear_transform_loops (struct loops *);
 803
 804 /* In tree-data-ref.c  */
 805 extern void tree_check_data_deps (struct loops *);
 806
 807 /* In tree-elim-checks.c  */
 808 extern void eliminate_redundant_checks (struct loops *);
 809
 810 /* In tree-ssa-loop-ivopts.c  */
 811 bool expr_invariant_in_loop_p (struct loop *, tree);
 812 bool multiplier_allowed_in_address_p (HOST_WIDE_INT);
 813 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode);
 814
 815 /* In tree-ssa-threadupdate.c.  */
 816 extern bool thread_through_all_blocks (bitmap);
 817
 818 /* In gimplify.c  */
 819 tree force_gimple_operand (tree, tree *, bool, tree);
 820 tree force_gimple_operand_bsi (block_stmt_iterator *, tree, bool, tree);
 821
 822 /* In tree-ssa-structalias.c */
 823 bool find_what_p_points_to (tree);
 824
 825 /* In tree-ssa-address.c  */
 826
 827 /* Affine combination of trees.  We keep track of at most MAX_AFF_ELTS elements
 828    to make things simpler; this is sufficient in most cases.  */
 829
 830 #define MAX_AFF_ELTS 8
 831
 832 struct affine_tree_combination
 833 {
 834   /* Type of the result of the combination.  */
 835   tree type;
 836
 837   /* Mask modulo that the operations are performed.  */
 838   unsigned HOST_WIDE_INT mask;
 839
 840   /* Constant offset.  */
 841   unsigned HOST_WIDE_INT offset;
 842
 843   /* Number of elements of the combination.  */
 844   unsigned n;
 845
 846   /* Elements and their coefficients.  */
 847   tree elts[MAX_AFF_ELTS];
 848   unsigned HOST_WIDE_INT coefs[MAX_AFF_ELTS];
 849
 850   /* Remainder of the expression.  */
 851   tree rest;
 852 };
 853
 854 /* Description of a memory address.  */
 855
 856 struct mem_address
 857 {
 858   tree symbol, base, index, step, offset;
 859 };
 860
 861 tree create_mem_ref (block_stmt_iterator *, tree,
 862                      struct affine_tree_combination *);
 863 rtx addr_for_mem_ref (struct mem_address *, bool);
 864 void get_address_description (tree, struct mem_address *);
 865 tree maybe_fold_tmr (tree);
 866 /* This structure is simply used during pushing fields onto the fieldstack
 867    to track the offset of the field, since bitpos_of_field gives it relative
 868    to its immediate containing type, and we want it relative to the ultimate
 869    containing object.  */
 870
 871 struct fieldoff
 872 {
 873   tree field;
 874   HOST_WIDE_INT offset;
 875 };
 876 typedef struct fieldoff fieldoff_s;
 877
 878 DEF_VEC_O(fieldoff_s);
 879 DEF_VEC_ALLOC_O(fieldoff_s,heap);
 880 int push_fields_onto_fieldstack (tree, VEC(fieldoff_s,heap) **,
 881                                  HOST_WIDE_INT, bool *);
 882 void sort_fieldstack (VEC(fieldoff_s,heap) *);
 883
 884 /* In tree-ssa-align.c  */
 885 extern void dump_align_info (FILE *);
 886 extern void debug_align_info (void);
 887
 888 void init_alias_heapvars (void);
 889 void delete_alias_heapvars (void);
 890
 891 #include "tree-flow-inline.h"
 892
 893 void swap_tree_operands (tree, tree *, tree *);
 894
 895 #endif /* _TREE_FLOW_H  */