gcc/tree-flow.h

   1 /* Data and Control Flow Analysis for Trees.
   2    Copyright (C) 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009
   3    Free Software Foundation, Inc.
   4    Contributed by Diego Novillo <dnovillo@redhat.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 3, or (at your option)
  11 any later version.
  12
  13 GCC is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License 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 #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 "gimple.h"
  30 #include "tree-ssa-operands.h"
  31 #include "cgraph.h"
  32 #include "ipa-reference.h"
  33 #include "tree-ssa-alias.h"
  34
  35
  36 /* Gimple dataflow datastructure. All publicly available fields shall have
  37    gimple_ accessor defined in tree-flow-inline.h, all publicly modifiable
  38    fields should have gimple_set accessor.  */
  39 struct GTY(()) gimple_df {
  40   /* Array of all variables referenced in the function.  */
  41   htab_t GTY((param_is (union tree_node))) referenced_vars;
  42
  43   /* A vector of all the noreturn calls passed to modify_stmt.
  44      cleanup_control_flow uses it to detect cases where a mid-block
  45      indirect call has been turned into a noreturn call.  When this
  46      happens, all the instructions after the call are no longer
  47      reachable and must be deleted as dead.  */
  48   VEC(gimple,gc) *modified_noreturn_calls;
  49
  50   /* Array of all SSA_NAMEs used in the function.  */
  51   VEC(tree,gc) *ssa_names;
  52
  53   /* Artificial variable used for the virtual operand FUD chain.  */
  54   tree vop;
  55
  56   /* The PTA solution for the ESCAPED artificial variable.  */
  57   struct pt_solution escaped;
  58
  59   /* The PTA solution for the CALLUSED artificial variable.  */
  60   struct pt_solution callused;
  61
  62   /* A map of decls to artificial ssa-names that point to the partition
  63      of the decl.  */
  64   struct pointer_map_t * GTY((skip(""))) decls_to_pointers;
  65
  66   /* Free list of SSA_NAMEs.  */
  67   tree free_ssanames;
  68
  69   /* Hashtable holding definition for symbol.  If this field is not NULL, it
  70      means that the first reference to this variable in the function is a
  71      USE or a VUSE.  In those cases, the SSA renamer creates an SSA name
  72      for this variable with an empty defining statement.  */
  73   htab_t GTY((param_is (union tree_node))) default_defs;
  74
  75   /* Symbols whose SSA form needs to be updated or created for the first
  76      time.  */
  77   bitmap syms_to_rename;
  78
  79   /* True if the code is in ssa form.  */
  80   unsigned int in_ssa_p : 1;
  81
  82   struct ssa_operands ssa_operands;
  83 };
  84
  85 /* Accessors for internal use only.  Generic code should use abstraction
  86    provided by tree-flow-inline.h or specific modules.  */
  87 #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames
  88 #define SSANAMES(fun) (fun)->gimple_df->ssa_names
  89 #define MODIFIED_NORETURN_CALLS(fun) (fun)->gimple_df->modified_noreturn_calls
  90 #define DEFAULT_DEFS(fun) (fun)->gimple_df->default_defs
  91 #define SYMS_TO_RENAME(fun) (fun)->gimple_df->syms_to_rename
  92
  93 typedef struct
  94 {
  95   htab_t htab;
  96   PTR *slot;
  97   PTR *limit;
  98 } htab_iterator;
  99
 100 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
 101    storing each element in RESULT, which is of type TYPE.  */
 102 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
 103   for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
 104         !end_htab_p (&(ITER)); \
 105         RESULT = (TYPE) next_htab_element (&(ITER)))
 106
 107 /*---------------------------------------------------------------------------
 108                       Attributes for SSA_NAMEs.
 109
 110   NOTE: These structures are stored in struct tree_ssa_name
 111   but are only used by the tree optimizers, so it makes better sense
 112   to declare them here to avoid recompiling unrelated files when
 113   making changes.
 114 ---------------------------------------------------------------------------*/
 115
 116 /* Aliasing information for SSA_NAMEs representing pointer variables.  */
 117 struct GTY(()) ptr_info_def
 118 {
 119   /* The points-to solution, TBAA-pruned if the pointer is dereferenced.  */
 120   struct pt_solution pt;
 121 };
 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
 149 /* The "no alias" attribute allows alias analysis to make more
 150    aggressive assumptions when assigning alias sets, computing
 151    points-to information and memory partitions.  These attributes
 152    are the result of user annotations or flags (e.g.,
 153    -fargument-noalias).  */
 154 enum noalias_state {
 155     /* Default state.  No special assumptions can be made about this
 156        symbol.  */
 157     MAY_ALIAS = 0,
 158
 159     /* The symbol does not alias with other symbols that have a
 160        NO_ALIAS* attribute.  */
 161     NO_ALIAS,
 162
 163     /* The symbol does not alias with other symbols that have a
 164        NO_ALIAS*, and it may not alias with global symbols.  */
 165     NO_ALIAS_GLOBAL,
 166
 167     /* The symbol does not alias with any other symbols.  */
 168     NO_ALIAS_ANYTHING
 169 };
 170
 171
 172 struct GTY(()) var_ann_d {
 173   /* Used when building base variable structures in a var_map.  */
 174   unsigned base_var_processed : 1;
 175
 176   /* Nonzero if this variable was used after SSA optimizations were
 177      applied.  We set this when translating out of SSA form.  */
 178   unsigned used : 1;
 179
 180   /* This field indicates whether or not the variable may need PHI nodes.
 181      See the enum's definition for more detailed information about the
 182      states.  */
 183   ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
 184
 185   /* True for HEAP artificial variables.  These variables represent
 186      the memory area allocated by a call to malloc.  */
 187   unsigned is_heapvar : 1;
 188
 189   /* This field describes several "no alias" attributes that some
 190      symbols are known to have.  See the enum's definition for more
 191      information on each attribute.  */
 192   ENUM_BITFIELD (noalias_state) noalias_state : 2;
 193
 194   /* Used by var_map for the base index of ssa base variables.  */
 195   unsigned base_index;
 196
 197   /* During into-ssa and the dominator optimizer, this field holds the
 198      current version of this variable (an SSA_NAME).  */
 199   tree current_def;
 200 };
 201
 202
 203 /* Immediate use lists are used to directly access all uses for an SSA
 204    name and get pointers to the statement for each use.
 205
 206    The structure ssa_use_operand_d consists of PREV and NEXT pointers
 207    to maintain the list.  A USE pointer, which points to address where
 208    the use is located and a LOC pointer which can point to the
 209    statement where the use is located, or, in the case of the root
 210    node, it points to the SSA name itself.
 211
 212    The list is anchored by an occurrence of ssa_operand_d *in* the
 213    ssa_name node itself (named 'imm_uses').  This node is uniquely
 214    identified by having a NULL USE pointer. and the LOC pointer
 215    pointing back to the ssa_name node itself.  This node forms the
 216    base for a circular list, and initially this is the only node in
 217    the list.
 218
 219    Fast iteration allows each use to be examined, but does not allow
 220    any modifications to the uses or stmts.
 221
 222    Normal iteration allows insertion, deletion, and modification. the
 223    iterator manages this by inserting a marker node into the list
 224    immediately before the node currently being examined in the list.
 225    this marker node is uniquely identified by having null stmt *and* a
 226    null use pointer.
 227
 228    When iterating to the next use, the iteration routines check to see
 229    if the node after the marker has changed. if it has, then the node
 230    following the marker is now the next one to be visited. if not, the
 231    marker node is moved past that node in the list (visualize it as
 232    bumping the marker node through the list).  this continues until
 233    the marker node is moved to the original anchor position. the
 234    marker node is then removed from the list.
 235
 236    If iteration is halted early, the marker node must be removed from
 237    the list before continuing.  */
 238 typedef struct immediate_use_iterator_d
 239 {
 240   /* This is the current use the iterator is processing.  */
 241   ssa_use_operand_t *imm_use;
 242   /* This marks the last use in the list (use node from SSA_NAME)  */
 243   ssa_use_operand_t *end_p;
 244   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 245   ssa_use_operand_t iter_node;
 246   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 247      the next one is traversed to, so it must be cached early.  */
 248   ssa_use_operand_t *next_imm_name;
 249 } imm_use_iterator;
 250
 251
 252 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 253    modifying stmts will cause this iterator to malfunction.  */
 254
 255 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)                       \
 256   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 257        !end_readonly_imm_use_p (&(ITER));                       \
 258        (DEST) = next_readonly_imm_use (&(ITER)))
 259
 260 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 261
 262 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 263   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 264        !end_imm_use_stmt_p (&(ITER));                           \
 265        (STMT) = next_imm_use_stmt (&(ITER)))
 266
 267 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 268    do so will result in leaving a iterator marker node in the immediate
 269    use list, and nothing good will come from that.   */
 270 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 271    {                                                            \
 272      end_imm_use_stmt_traverse (&(ITER));                       \
 273      break;                                                     \
 274    }
 275
 276
 277 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 278    get access to each occurrence of ssavar on the stmt returned by
 279    that iterator..  for instance:
 280
 281      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 282        {
 283          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 284            {
 285              SET_USE (use_p, blah);
 286            }
 287          update_stmt (stmt);
 288        }                                                         */
 289
 290 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 291   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 292        !end_imm_use_on_stmt_p (&(ITER));                        \
 293        (DEST) = next_imm_use_on_stmt (&(ITER)))
 294
 295
 296
 297 typedef struct var_ann_d *var_ann_t;
 298
 299 static inline var_ann_t var_ann (const_tree);
 300 static inline var_ann_t get_var_ann (tree);
 301 static inline void update_stmt (gimple);
 302 static inline int get_lineno (const_gimple);
 303
 304 /*---------------------------------------------------------------------------
 305                   Structure representing predictions in tree level.
 306 ---------------------------------------------------------------------------*/
 307 struct GTY((chain_next ("%h.ep_next"))) edge_prediction {
 308   struct edge_prediction *ep_next;
 309   edge ep_edge;
 310   enum br_predictor ep_predictor;
 311   int ep_probability;
 312 };
 313
 314 /* Accessors for basic block annotations.  */
 315 static inline gimple_seq phi_nodes (const_basic_block);
 316 static inline void set_phi_nodes (basic_block, gimple_seq);
 317
 318 /*---------------------------------------------------------------------------
 319                               Global declarations
 320 ---------------------------------------------------------------------------*/
 321 struct GTY(()) int_tree_map {
 322
 323   unsigned int uid;
 324   tree to;
 325 };
 326
 327 extern unsigned int int_tree_map_hash (const void *);
 328 extern int int_tree_map_eq (const void *, const void *);
 329
 330 extern unsigned int uid_decl_map_hash (const void *);
 331 extern int uid_decl_map_eq (const void *, const void *);
 332
 333 typedef struct
 334 {
 335   htab_iterator hti;
 336 } referenced_var_iterator;
 337
 338 /* This macro loops over all the referenced vars, one at a time, putting the
 339    current var in VAR.  Note:  You are not allowed to add referenced variables
 340    to the hashtable while using this macro.  Doing so may cause it to behave
 341    erratically.  */
 342
 343 #define FOR_EACH_REFERENCED_VAR(VAR, ITER) \
 344   for ((VAR) = first_referenced_var (&(ITER)); \
 345        !end_referenced_vars_p (&(ITER)); \
 346        (VAR) = next_referenced_var (&(ITER)))
 347
 348 extern tree referenced_var_lookup (unsigned int);
 349 extern bool referenced_var_check_and_insert (tree);
 350 #define num_referenced_vars htab_elements (gimple_referenced_vars (cfun))
 351 #define referenced_var(i) referenced_var_lookup (i)
 352
 353 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
 354 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
 355
 356 /* Macros for showing usage statistics.  */
 357 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 358                   ? (x)                                 \
 359                   : ((x) < 1024*1024*10                 \
 360                      ? (x) / 1024                       \
 361                      : (x) / (1024*1024))))
 362
 363 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 364
 365 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 366
 367 /*---------------------------------------------------------------------------
 368                               OpenMP Region Tree
 369 ---------------------------------------------------------------------------*/
 370
 371 /* Parallel region information.  Every parallel and workshare
 372    directive is enclosed between two markers, the OMP_* directive
 373    and a corresponding OMP_RETURN statement.  */
 374
 375 struct omp_region
 376 {
 377   /* The enclosing region.  */
 378   struct omp_region *outer;
 379
 380   /* First child region.  */
 381   struct omp_region *inner;
 382
 383   /* Next peer region.  */
 384   struct omp_region *next;
 385
 386   /* Block containing the omp directive as its last stmt.  */
 387   basic_block entry;
 388
 389   /* Block containing the OMP_RETURN as its last stmt.  */
 390   basic_block exit;
 391
 392   /* Block containing the OMP_CONTINUE as its last stmt.  */
 393   basic_block cont;
 394
 395   /* If this is a combined parallel+workshare region, this is a list
 396      of additional arguments needed by the combined parallel+workshare
 397      library call.  */
 398   tree ws_args;
 399
 400   /* The code for the omp directive of this region.  */
 401   enum gimple_code type;
 402
 403   /* Schedule kind, only used for OMP_FOR type regions.  */
 404   enum omp_clause_schedule_kind sched_kind;
 405
 406   /* True if this is a combined parallel+workshare region.  */
 407   bool is_combined_parallel;
 408 };
 409
 410 extern struct omp_region *root_omp_region;
 411 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 412                                           struct omp_region *);
 413 extern void free_omp_regions (void);
 414 void omp_expand_local (basic_block);
 415 extern tree find_omp_clause (tree, enum omp_clause_code);
 416 tree copy_var_decl (tree, tree, tree);
 417
 418 /*---------------------------------------------------------------------------
 419                               Function prototypes
 420 ---------------------------------------------------------------------------*/
 421 /* In tree-cfg.c  */
 422
 423 /* Location to track pending stmt for edge insertion.  */
 424 #define PENDING_STMT(e) ((e)->insns.g)
 425
 426 extern void delete_tree_cfg_annotations (void);
 427 extern bool stmt_ends_bb_p (gimple);
 428 extern bool is_ctrl_stmt (gimple);
 429 extern bool is_ctrl_altering_stmt (gimple);
 430 extern bool simple_goto_p (gimple);
 431 extern bool stmt_can_make_abnormal_goto (gimple);
 432 extern basic_block single_noncomplex_succ (basic_block bb);
 433 extern void gimple_dump_bb (basic_block, FILE *, int, int);
 434 extern void gimple_debug_bb (basic_block);
 435 extern basic_block gimple_debug_bb_n (int);
 436 extern void gimple_dump_cfg (FILE *, int);
 437 extern void gimple_debug_cfg (int);
 438 extern void dump_cfg_stats (FILE *);
 439 extern void dot_cfg (void);
 440 extern void debug_cfg_stats (void);
 441 extern void debug_loops (int);
 442 extern void debug_loop (struct loop *, int);
 443 extern void debug_loop_num (unsigned, int);
 444 extern void print_loops (FILE *, int);
 445 extern void print_loops_bb (FILE *, basic_block, int, int);
 446 extern void cleanup_dead_labels (void);
 447 extern void group_case_labels (void);
 448 extern gimple first_stmt (basic_block);
 449 extern gimple last_stmt (basic_block);
 450 extern gimple last_and_only_stmt (basic_block);
 451 extern edge find_taken_edge (basic_block, tree);
 452 extern basic_block label_to_block_fn (struct function *, tree);
 453 #define label_to_block(t) (label_to_block_fn (cfun, t))
 454 extern void notice_special_calls (gimple);
 455 extern void clear_special_calls (void);
 456 extern void verify_stmts (void);
 457 extern void verify_gimple (void);
 458 extern void verify_types_in_gimple_seq (gimple_seq);
 459 extern tree gimple_block_label (basic_block);
 460 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 461 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 462                                         basic_block *);
 463 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 464                                       basic_block *);
 465 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 466                                           VEC(basic_block,heap) **bbs_p);
 467 extern void add_phi_args_after_copy_bb (basic_block);
 468 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 469 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 470 extern bool gimple_purge_dead_eh_edges (basic_block);
 471 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 472 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 473                              tree, tree);
 474 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 475                              tree, tree, tree);
 476 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 477                              tree, tree, tree, tree);
 478 extern void init_empty_tree_cfg (void);
 479 extern void init_empty_tree_cfg_for_function (struct function *);
 480 extern void fold_cond_expr_cond (void);
 481 extern void make_abnormal_goto_edges (basic_block, bool);
 482 extern void replace_uses_by (tree, tree);
 483 extern void start_recording_case_labels (void);
 484 extern void end_recording_case_labels (void);
 485 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 486                                            basic_block, tree);
 487 void remove_edge_and_dominated_blocks (edge);
 488 void mark_virtual_ops_in_bb (basic_block);
 489 bool tree_node_can_be_shared (tree);
 490
 491 /* In tree-cfgcleanup.c  */
 492 extern bitmap cfgcleanup_altered_bbs;
 493 extern bool cleanup_tree_cfg (void);
 494
 495 /* In tree-pretty-print.c.  */
 496 extern void dump_generic_bb (FILE *, basic_block, int, int);
 497 extern int op_code_prio (enum tree_code);
 498 extern int op_prio (const_tree);
 499 extern const char *op_symbol_code (enum tree_code);
 500
 501 /* In tree-dfa.c  */
 502 extern var_ann_t create_var_ann (tree);
 503 extern void renumber_gimple_stmt_uids (void);
 504 extern void renumber_gimple_stmt_uids_in_blocks (basic_block *, int);
 505 extern void dump_dfa_stats (FILE *);
 506 extern void debug_dfa_stats (void);
 507 extern void debug_referenced_vars (void);
 508 extern void dump_referenced_vars (FILE *);
 509 extern void dump_variable (FILE *, tree);
 510 extern void debug_variable (tree);
 511 extern tree get_virtual_var (tree);
 512 extern bool add_referenced_var (tree);
 513 extern void remove_referenced_var (tree);
 514 extern void mark_symbols_for_renaming (gimple);
 515 extern void find_new_referenced_vars (gimple);
 516 extern tree make_rename_temp (tree, const char *);
 517 extern void set_default_def (tree, tree);
 518 extern tree gimple_default_def (struct function *, tree);
 519 extern bool stmt_references_abnormal_ssa_name (gimple);
 520 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
 521                                      HOST_WIDE_INT *, HOST_WIDE_INT *);
 522 extern void find_referenced_vars_in (gimple);
 523
 524 /* In tree-phinodes.c  */
 525 extern void reserve_phi_args_for_new_edge (basic_block);
 526 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 527 extern gimple make_phi_node (tree var, int len);
 528 extern gimple create_phi_node (tree, basic_block);
 529 extern void add_phi_arg (gimple, tree, edge, source_location);
 530 extern void remove_phi_args (edge);
 531 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 532 extern void remove_phi_nodes (basic_block);
 533 extern void init_phinodes (void);
 534 extern void fini_phinodes (void);
 535 extern void release_phi_node (gimple);
 536 #ifdef GATHER_STATISTICS
 537 extern void phinodes_print_statistics (void);
 538 #endif
 539
 540 /* In gimple-low.c  */
 541 extern void record_vars_into (tree, tree);
 542 extern void record_vars (tree);
 543 extern bool block_may_fallthru (const_tree);
 544 extern bool gimple_seq_may_fallthru (gimple_seq);
 545 extern bool gimple_stmt_may_fallthru (gimple);
 546 extern bool gimple_check_call_args (gimple);
 547
 548
 549 /* In tree-ssa.c  */
 550
 551 /* Mapping for redirected edges.  */
 552 struct GTY(()) _edge_var_map {
 553   tree result;                  /* PHI result.  */
 554   tree def;                     /* PHI arg definition.  */
 555   source_location locus;        /* PHI arg location.  */
 556 };
 557 typedef struct _edge_var_map edge_var_map;
 558
 559 DEF_VEC_O(edge_var_map);
 560 DEF_VEC_ALLOC_O(edge_var_map, heap);
 561
 562 /* A vector of var maps.  */
 563 typedef VEC(edge_var_map, heap) *edge_var_map_vector;
 564
 565 extern void init_tree_ssa (struct function *);
 566 extern void redirect_edge_var_map_add (edge, tree, tree, source_location);
 567 extern void redirect_edge_var_map_clear (edge);
 568 extern void redirect_edge_var_map_dup (edge, edge);
 569 extern edge_var_map_vector redirect_edge_var_map_vector (edge);
 570 extern void redirect_edge_var_map_destroy (void);
 571
 572 extern edge ssa_redirect_edge (edge, basic_block);
 573 extern void flush_pending_stmts (edge);
 574 extern void verify_ssa (bool);
 575 extern void delete_tree_ssa (void);
 576 extern bool ssa_undefined_value_p (tree);
 577 extern void execute_update_addresses_taken (bool);
 578
 579 /* Call-back function for walk_use_def_chains().  At each reaching
 580    definition, a function with this prototype is called.  */
 581 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *);
 582
 583 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 584
 585 void insert_debug_temps_for_defs (gimple_stmt_iterator *);
 586 void insert_debug_temp_for_var_def (gimple_stmt_iterator *, tree);
 587 void release_defs_bitset (bitmap toremove);
 588
 589 /* In tree-into-ssa.c  */
 590 void update_ssa (unsigned);
 591 void delete_update_ssa (void);
 592 void register_new_name_mapping (tree, tree);
 593 tree create_new_def_for (tree, gimple, def_operand_p);
 594 bool need_ssa_update_p (struct function *);
 595 bool name_mappings_registered_p (void);
 596 bool name_registered_for_update_p (tree);
 597 bitmap ssa_names_to_replace (void);
 598 void release_ssa_name_after_update_ssa (tree);
 599 void compute_global_livein (bitmap, bitmap);
 600 void mark_sym_for_renaming (tree);
 601 void mark_set_for_renaming (bitmap);
 602 tree get_current_def (tree);
 603 void set_current_def (tree, tree);
 604
 605 /* In tree-ssanames.c  */
 606 extern void init_ssanames (struct function *, int);
 607 extern void fini_ssanames (void);
 608 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 609 extern tree duplicate_ssa_name (tree, gimple);
 610 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 611 extern void release_ssa_name (tree);
 612 extern void release_defs (gimple);
 613 extern void replace_ssa_name_symbol (tree, tree);
 614
 615 #ifdef GATHER_STATISTICS
 616 extern void ssanames_print_statistics (void);
 617 #endif
 618
 619 /* In tree-ssa-ccp.c  */
 620 bool fold_stmt (gimple_stmt_iterator *);
 621 bool fold_stmt_inplace (gimple);
 622 tree get_symbol_constant_value (tree);
 623 tree fold_const_aggregate_ref (tree);
 624 bool may_propagate_address_into_dereference (tree, tree);
 625
 626
 627 /* In tree-ssa-dom.c  */
 628 extern void dump_dominator_optimization_stats (FILE *);
 629 extern void debug_dominator_optimization_stats (void);
 630 int loop_depth_of_name (tree);
 631 tree degenerate_phi_result (gimple);
 632
 633 /* In tree-ssa-copy.c  */
 634 extern void propagate_value (use_operand_p, tree);
 635 extern void propagate_tree_value (tree *, tree);
 636 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 637 extern void replace_exp (use_operand_p, tree);
 638 extern bool may_propagate_copy (tree, tree);
 639 extern bool may_propagate_copy_into_stmt (gimple, tree);
 640 extern bool may_propagate_copy_into_asm (tree);
 641
 642 /* Affine iv.  */
 643
 644 typedef struct
 645 {
 646   /* Iv = BASE + STEP * i.  */
 647   tree base, step;
 648
 649   /* True if this iv does not overflow.  */
 650   bool no_overflow;
 651 } affine_iv;
 652
 653 /* Description of number of iterations of a loop.  All the expressions inside
 654    the structure can be evaluated at the end of the loop's preheader
 655    (and due to ssa form, also anywhere inside the body of the loop).  */
 656
 657 struct tree_niter_desc
 658 {
 659   tree assumptions;     /* The boolean expression.  If this expression evaluates
 660                            to false, then the other fields in this structure
 661                            should not be used; there is no guarantee that they
 662                            will be correct.  */
 663   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 664                            the loop will exit in the first iteration (i.e.
 665                            its latch will not be executed), even if the niter
 666                            field says otherwise.  */
 667   tree niter;           /* The expression giving the number of iterations of
 668                            a loop (provided that assumptions == true and
 669                            may_be_zero == false), more precisely the number
 670                            of executions of the latch of the loop.  */
 671   double_int max;       /* The upper bound on the number of iterations of
 672                            the loop.  */
 673
 674   /* The simplified shape of the exit condition.  The loop exits if
 675      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 676      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 677      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 678      by loop unrolling.  */
 679   affine_iv control;
 680   tree bound;
 681   enum tree_code cmp;
 682 };
 683
 684 /* In tree-ssa-phiopt.c */
 685 bool empty_block_p (basic_block);
 686 basic_block *blocks_in_phiopt_order (void);
 687
 688 /* In tree-ssa-loop*.c  */
 689
 690 void tree_ssa_lim (void);
 691 unsigned int tree_ssa_unswitch_loops (void);
 692 unsigned int canonicalize_induction_variables (void);
 693 unsigned int tree_unroll_loops_completely (bool, bool);
 694 unsigned int tree_ssa_prefetch_arrays (void);
 695 void tree_ssa_iv_optimize (void);
 696 unsigned tree_predictive_commoning (void);
 697 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 698 bool parallelize_loops (void);
 699
 700 bool loop_only_exit_p (const struct loop *, const_edge);
 701 bool number_of_iterations_exit (struct loop *, edge,
 702                                 struct tree_niter_desc *niter, bool);
 703 tree find_loop_niter (struct loop *, edge *);
 704 tree loop_niter_by_eval (struct loop *, edge);
 705 tree find_loop_niter_by_eval (struct loop *, edge *);
 706 void estimate_numbers_of_iterations (void);
 707 bool array_at_struct_end_p (tree);
 708 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 709 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 710
 711 bool nowrap_type_p (tree);
 712 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 713 enum ev_direction scev_direction (const_tree);
 714
 715 void free_numbers_of_iterations_estimates (void);
 716 void free_numbers_of_iterations_estimates_loop (struct loop *);
 717 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 718 void verify_loop_closed_ssa (void);
 719 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 720 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 721                 tree *, tree *);
 722 basic_block split_loop_exit_edge (edge);
 723 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 724                                      bool *);
 725 basic_block ip_end_pos (struct loop *);
 726 basic_block ip_normal_pos (struct loop *);
 727 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 728                                          unsigned int, sbitmap,
 729                                          edge, VEC (edge, heap) **,
 730                                          int);
 731 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 732 void rename_variables_in_loop (struct loop *);
 733 void rename_variables_in_bb (basic_block bb);
 734 struct loop *tree_ssa_loop_version (struct loop *, tree,
 735                                     basic_block *);
 736 tree expand_simple_operations (tree);
 737 void substitute_in_loop_info (struct loop *, tree, tree);
 738 edge single_dom_exit (struct loop *);
 739 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 740                         struct tree_niter_desc *niter);
 741 void tree_unroll_loop (struct loop *, unsigned,
 742                        edge, struct tree_niter_desc *);
 743 typedef void (*transform_callback)(struct loop *, void *);
 744 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 745                                      edge, struct tree_niter_desc *,
 746                                      transform_callback, void *);
 747 bool contains_abnormal_ssa_name_p (tree);
 748 bool stmt_dominates_stmt_p (gimple, gimple);
 749 void mark_virtual_ops_for_renaming (gimple);
 750
 751 /* In tree-ssa-dce.c */
 752 void mark_virtual_phi_result_for_renaming (gimple);
 753
 754 /* In tree-ssa-threadedge.c */
 755 extern void threadedge_initialize_values (void);
 756 extern void threadedge_finalize_values (void);
 757 extern VEC(tree,heap) *ssa_name_values;
 758 #define SSA_NAME_VALUE(x) \
 759     (SSA_NAME_VERSION(x) < VEC_length(tree, ssa_name_values) \
 760      ? VEC_index(tree, ssa_name_values, SSA_NAME_VERSION(x)) \
 761      : NULL_TREE)
 762 extern void set_ssa_name_value (tree, tree);
 763 extern bool potentially_threadable_block (basic_block);
 764 extern void thread_across_edge (gimple, edge, bool,
 765                                 VEC(tree, heap) **, tree (*) (gimple, gimple));
 766
 767 /* In tree-ssa-loop-im.c  */
 768 /* The possibilities of statement movement.  */
 769
 770 enum move_pos
 771   {
 772     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 773     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 774                                    become executed -- memory accesses, ... */
 775     MOVE_POSSIBLE               /* Unlimited movement.  */
 776   };
 777 extern enum move_pos movement_possibility (gimple);
 778 char *get_lsm_tmp_name (tree, unsigned);
 779
 780 /* In tree-flow-inline.h  */
 781 static inline bool is_call_clobbered (const_tree);
 782 static inline void set_is_used (tree);
 783 static inline bool unmodifiable_var_p (const_tree);
 784 static inline bool ref_contains_array_ref (const_tree);
 785 static inline bool array_ref_contains_indirect_ref (const_tree);
 786
 787 /* In tree-eh.c  */
 788 extern void make_eh_edges (gimple);
 789 extern bool make_eh_dispatch_edges (gimple);
 790 extern edge redirect_eh_edge (edge, basic_block);
 791 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 792 extern bool tree_could_trap_p (tree);
 793 extern bool operation_could_trap_helper_p (enum tree_code, bool, bool, bool,
 794                                            bool, tree, bool *);
 795 extern bool operation_could_trap_p (enum tree_code, bool, bool, tree);
 796 extern bool stmt_could_throw_p (gimple);
 797 extern bool tree_could_throw_p (tree);
 798 extern bool stmt_can_throw_internal (gimple);
 799 extern bool stmt_can_throw_external (gimple);
 800 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 801 extern void add_stmt_to_eh_lp (gimple, int);
 802 extern bool remove_stmt_from_eh_lp (gimple);
 803 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 804 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 805 extern int lookup_stmt_eh_lp (gimple);
 806 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 807 extern bool maybe_clean_eh_stmt (gimple);
 808 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 809 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 810                                         struct function *, gimple,
 811                                         struct pointer_map_t *, int);
 812 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 813 extern bool verify_eh_edges (gimple);
 814 extern bool verify_eh_dispatch_edge (gimple);
 815
 816 /* In tree-ssa-pre.c  */
 817 struct pre_expr_d;
 818 void add_to_value (unsigned int, struct pre_expr_d *);
 819 void debug_value_expressions (unsigned int);
 820 void print_value_expressions (FILE *, unsigned int);
 821
 822 /* In tree-ssa-sink.c  */
 823 bool is_hidden_global_store (gimple);
 824
 825 /* In tree-loop-linear.c  */
 826 extern void linear_transform_loops (void);
 827 extern unsigned perfect_loop_nest_depth (struct loop *);
 828
 829 /* In graphite.c  */
 830 extern void graphite_transform_loops (void);
 831
 832 /* In tree-data-ref.c  */
 833 extern void tree_check_data_deps (void);
 834
 835 /* In tree-ssa-loop-ivopts.c  */
 836 bool expr_invariant_in_loop_p (struct loop *, tree);
 837 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 838 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 839                                       addr_space_t);
 840 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode, bool);
 841
 842 /* In tree-ssa-threadupdate.c.  */
 843 extern bool thread_through_all_blocks (bool);
 844 extern void register_jump_thread (edge, edge);
 845
 846 /* In gimplify.c  */
 847 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 848 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 849                                bool, enum gsi_iterator_update);
 850 tree gimple_fold_indirect_ref (tree);
 851
 852 /* In tree-ssa-live.c */
 853 extern void remove_unused_locals (void);
 854 extern void dump_scope_blocks (FILE *, int);
 855 extern void debug_scope_blocks (int);
 856 extern void debug_scope_block (tree, int);
 857
 858 /* In tree-ssa-address.c  */
 859
 860 /* Description of a memory address.  */
 861
 862 struct mem_address
 863 {
 864   tree symbol, base, index, step, offset;
 865 };
 866
 867 struct affine_tree_combination;
 868 tree create_mem_ref (gimple_stmt_iterator *, tree,
 869                      struct affine_tree_combination *, tree, bool);
 870 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 871 void get_address_description (tree, struct mem_address *);
 872 tree maybe_fold_tmr (tree);
 873
 874 unsigned int execute_free_datastructures (void);
 875 unsigned int execute_fixup_cfg (void);
 876
 877 #include "tree-flow-inline.h"
 878
 879 void swap_tree_operands (gimple, tree *, tree *);
 880
 881 int least_common_multiple (int, int);
 882
 883 #endif /* _TREE_FLOW_H  */