gcc/tree-flow.h

   1 /* Data and Control Flow Analysis for Trees.
   2    Copyright (C) 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
   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   /* A map of decls to artificial ssa-names that point to the partition
  60      of the decl.  */
  61   struct pointer_map_t * GTY((skip(""))) decls_to_pointers;
  62
  63   /* Free list of SSA_NAMEs.  */
  64   tree free_ssanames;
  65
  66   /* Hashtable holding definition for symbol.  If this field is not NULL, it
  67      means that the first reference to this variable in the function is a
  68      USE or a VUSE.  In those cases, the SSA renamer creates an SSA name
  69      for this variable with an empty defining statement.  */
  70   htab_t GTY((param_is (union tree_node))) default_defs;
  71
  72   /* Symbols whose SSA form needs to be updated or created for the first
  73      time.  */
  74   bitmap syms_to_rename;
  75
  76   /* True if the code is in ssa form.  */
  77   unsigned int in_ssa_p : 1;
  78
  79   /* True if IPA points-to information was computed for this function.  */
  80   unsigned int ipa_pta : 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
 118 struct GTY(()) ptr_info_def
 119 {
 120   /* The points-to solution.  */
 121   struct pt_solution pt;
 122 };
 123
 124
 125 /* It is advantageous to avoid things like life analysis for variables which
 126    do not need PHI nodes.  This enum describes whether or not a particular
 127    variable may need a PHI node.  */
 128
 129 enum need_phi_state {
 130   /* This is the default.  If we are still in this state after finding
 131      all the definition and use sites, then we will assume the variable
 132      needs PHI nodes.  This is probably an overly conservative assumption.  */
 133   NEED_PHI_STATE_UNKNOWN,
 134
 135   /* This state indicates that we have seen one or more sets of the
 136      variable in a single basic block and that the sets dominate all
 137      uses seen so far.  If after finding all definition and use sites
 138      we are still in this state, then the variable does not need any
 139      PHI nodes.  */
 140   NEED_PHI_STATE_NO,
 141
 142   /* This state indicates that we have either seen multiple definitions of
 143      the variable in multiple blocks, or that we encountered a use in a
 144      block that was not dominated by the block containing the set(s) of
 145      this variable.  This variable is assumed to need PHI nodes.  */
 146   NEED_PHI_STATE_MAYBE
 147 };
 148
 149
 150 /* The "no alias" attribute allows alias analysis to make more
 151    aggressive assumptions when assigning alias sets, computing
 152    points-to information and memory partitions.  These attributes
 153    are the result of user annotations or flags (e.g.,
 154    -fargument-noalias).  */
 155 enum noalias_state {
 156     /* Default state.  No special assumptions can be made about this
 157        symbol.  */
 158     MAY_ALIAS = 0,
 159
 160     /* The symbol does not alias with other symbols that have a
 161        NO_ALIAS* attribute.  */
 162     NO_ALIAS,
 163
 164     /* The symbol does not alias with other symbols that have a
 165        NO_ALIAS*, and it may not alias with global symbols.  */
 166     NO_ALIAS_GLOBAL,
 167
 168     /* The symbol does not alias with any other symbols.  */
 169     NO_ALIAS_ANYTHING
 170 };
 171
 172
 173 struct GTY(()) var_ann_d {
 174   /* Used when building base variable structures in a var_map.  */
 175   unsigned base_var_processed : 1;
 176
 177   /* Nonzero if this variable was used after SSA optimizations were
 178      applied.  We set this when translating out of SSA form.  */
 179   unsigned used : 1;
 180
 181   /* This field indicates whether or not the variable may need PHI nodes.
 182      See the enum's definition for more detailed information about the
 183      states.  */
 184   ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
 185
 186   /* True for HEAP artificial variables.  These variables represent
 187      the memory area allocated by a call to malloc.  */
 188   unsigned is_heapvar : 1;
 189
 190   /* This field describes several "no alias" attributes that some
 191      symbols are known to have.  See the enum's definition for more
 192      information on each attribute.  */
 193   ENUM_BITFIELD (noalias_state) noalias_state : 2;
 194
 195   /* Used by var_map for the base index of ssa base variables.  */
 196   unsigned base_index;
 197
 198   /* During into-ssa and the dominator optimizer, this field holds the
 199      current version of this variable (an SSA_NAME).  */
 200   tree current_def;
 201 };
 202
 203
 204 /* Immediate use lists are used to directly access all uses for an SSA
 205    name and get pointers to the statement for each use.
 206
 207    The structure ssa_use_operand_d consists of PREV and NEXT pointers
 208    to maintain the list.  A USE pointer, which points to address where
 209    the use is located and a LOC pointer which can point to the
 210    statement where the use is located, or, in the case of the root
 211    node, it points to the SSA name itself.
 212
 213    The list is anchored by an occurrence of ssa_operand_d *in* the
 214    ssa_name node itself (named 'imm_uses').  This node is uniquely
 215    identified by having a NULL USE pointer. and the LOC pointer
 216    pointing back to the ssa_name node itself.  This node forms the
 217    base for a circular list, and initially this is the only node in
 218    the list.
 219
 220    Fast iteration allows each use to be examined, but does not allow
 221    any modifications to the uses or stmts.
 222
 223    Normal iteration allows insertion, deletion, and modification. the
 224    iterator manages this by inserting a marker node into the list
 225    immediately before the node currently being examined in the list.
 226    this marker node is uniquely identified by having null stmt *and* a
 227    null use pointer.
 228
 229    When iterating to the next use, the iteration routines check to see
 230    if the node after the marker has changed. if it has, then the node
 231    following the marker is now the next one to be visited. if not, the
 232    marker node is moved past that node in the list (visualize it as
 233    bumping the marker node through the list).  this continues until
 234    the marker node is moved to the original anchor position. the
 235    marker node is then removed from the list.
 236
 237    If iteration is halted early, the marker node must be removed from
 238    the list before continuing.  */
 239 typedef struct immediate_use_iterator_d
 240 {
 241   /* This is the current use the iterator is processing.  */
 242   ssa_use_operand_t *imm_use;
 243   /* This marks the last use in the list (use node from SSA_NAME)  */
 244   ssa_use_operand_t *end_p;
 245   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 246   ssa_use_operand_t iter_node;
 247   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 248      the next one is traversed to, so it must be cached early.  */
 249   ssa_use_operand_t *next_imm_name;
 250 } imm_use_iterator;
 251
 252
 253 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 254    modifying stmts will cause this iterator to malfunction.  */
 255
 256 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)               \
 257   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 258        !end_readonly_imm_use_p (&(ITER));                       \
 259        (void) ((DEST) = next_readonly_imm_use (&(ITER))))
 260
 261 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 262
 263 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 264   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 265        !end_imm_use_stmt_p (&(ITER));                           \
 266        (void) ((STMT) = next_imm_use_stmt (&(ITER))))
 267
 268 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 269    do so will result in leaving a iterator marker node in the immediate
 270    use list, and nothing good will come from that.   */
 271 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 272    {                                                            \
 273      end_imm_use_stmt_traverse (&(ITER));                       \
 274      break;                                                     \
 275    }
 276
 277
 278 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 279    get access to each occurrence of ssavar on the stmt returned by
 280    that iterator..  for instance:
 281
 282      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 283        {
 284          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 285            {
 286              SET_USE (use_p, blah);
 287            }
 288          update_stmt (stmt);
 289        }                                                         */
 290
 291 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 292   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 293        !end_imm_use_on_stmt_p (&(ITER));                        \
 294        (void) ((DEST) = next_imm_use_on_stmt (&(ITER))))
 295
 296
 297
 298 typedef struct var_ann_d *var_ann_t;
 299
 300 static inline var_ann_t var_ann (const_tree);
 301 static inline var_ann_t get_var_ann (tree);
 302 static inline void update_stmt (gimple);
 303 static inline int get_lineno (const_gimple);
 304
 305 /*---------------------------------------------------------------------------
 306                   Structure representing predictions in tree level.
 307 ---------------------------------------------------------------------------*/
 308 struct GTY((chain_next ("%h.ep_next"))) edge_prediction {
 309   struct edge_prediction *ep_next;
 310   edge ep_edge;
 311   enum br_predictor ep_predictor;
 312   int ep_probability;
 313 };
 314
 315 /* Accessors for basic block annotations.  */
 316 static inline gimple_seq phi_nodes (const_basic_block);
 317 static inline void set_phi_nodes (basic_block, gimple_seq);
 318
 319 /*---------------------------------------------------------------------------
 320                               Global declarations
 321 ---------------------------------------------------------------------------*/
 322 struct GTY(()) int_tree_map {
 323
 324   unsigned int uid;
 325   tree to;
 326 };
 327
 328 extern unsigned int int_tree_map_hash (const void *);
 329 extern int int_tree_map_eq (const void *, const void *);
 330
 331 extern unsigned int uid_decl_map_hash (const void *);
 332 extern int uid_decl_map_eq (const void *, const void *);
 333
 334 typedef struct
 335 {
 336   htab_iterator hti;
 337 } referenced_var_iterator;
 338
 339 /* This macro loops over all the referenced vars, one at a time, putting the
 340    current var in VAR.  Note:  You are not allowed to add referenced variables
 341    to the hashtable while using this macro.  Doing so may cause it to behave
 342    erratically.  */
 343
 344 #define FOR_EACH_REFERENCED_VAR(VAR, ITER) \
 345   for ((VAR) = first_referenced_var (&(ITER)); \
 346        !end_referenced_vars_p (&(ITER)); \
 347        (VAR) = next_referenced_var (&(ITER)))
 348
 349 extern tree referenced_var_lookup (unsigned int);
 350 extern bool referenced_var_check_and_insert (tree);
 351 #define num_referenced_vars htab_elements (gimple_referenced_vars (cfun))
 352 #define referenced_var(i) referenced_var_lookup (i)
 353
 354 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
 355 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
 356
 357 /* Macros for showing usage statistics.  */
 358 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 359                   ? (x)                                 \
 360                   : ((x) < 1024*1024*10                 \
 361                      ? (x) / 1024                       \
 362                      : (x) / (1024*1024))))
 363
 364 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 365
 366 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 367
 368 /*---------------------------------------------------------------------------
 369                               OpenMP Region Tree
 370 ---------------------------------------------------------------------------*/
 371
 372 /* Parallel region information.  Every parallel and workshare
 373    directive is enclosed between two markers, the OMP_* directive
 374    and a corresponding OMP_RETURN statement.  */
 375
 376 struct omp_region
 377 {
 378   /* The enclosing region.  */
 379   struct omp_region *outer;
 380
 381   /* First child region.  */
 382   struct omp_region *inner;
 383
 384   /* Next peer region.  */
 385   struct omp_region *next;
 386
 387   /* Block containing the omp directive as its last stmt.  */
 388   basic_block entry;
 389
 390   /* Block containing the OMP_RETURN as its last stmt.  */
 391   basic_block exit;
 392
 393   /* Block containing the OMP_CONTINUE as its last stmt.  */
 394   basic_block cont;
 395
 396   /* If this is a combined parallel+workshare region, this is a list
 397      of additional arguments needed by the combined parallel+workshare
 398      library call.  */
 399   tree ws_args;
 400
 401   /* The code for the omp directive of this region.  */
 402   enum gimple_code type;
 403
 404   /* Schedule kind, only used for OMP_FOR type regions.  */
 405   enum omp_clause_schedule_kind sched_kind;
 406
 407   /* True if this is a combined parallel+workshare region.  */
 408   bool is_combined_parallel;
 409 };
 410
 411 extern struct omp_region *root_omp_region;
 412 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 413                                           struct omp_region *);
 414 extern void free_omp_regions (void);
 415 void omp_expand_local (basic_block);
 416 extern tree find_omp_clause (tree, enum omp_clause_code);
 417 tree copy_var_decl (tree, tree, tree);
 418
 419 /*---------------------------------------------------------------------------
 420                               Function prototypes
 421 ---------------------------------------------------------------------------*/
 422 /* In tree-cfg.c  */
 423
 424 /* Location to track pending stmt for edge insertion.  */
 425 #define PENDING_STMT(e) ((e)->insns.g)
 426
 427 extern void delete_tree_cfg_annotations (void);
 428 extern bool stmt_ends_bb_p (gimple);
 429 extern bool is_ctrl_stmt (gimple);
 430 extern bool is_ctrl_altering_stmt (gimple);
 431 extern bool simple_goto_p (gimple);
 432 extern bool stmt_can_make_abnormal_goto (gimple);
 433 extern basic_block single_noncomplex_succ (basic_block bb);
 434 extern void gimple_dump_bb (basic_block, FILE *, int, int);
 435 extern void gimple_debug_bb (basic_block);
 436 extern basic_block gimple_debug_bb_n (int);
 437 extern void gimple_dump_cfg (FILE *, int);
 438 extern void gimple_debug_cfg (int);
 439 extern void dump_cfg_stats (FILE *);
 440 extern void dot_cfg (void);
 441 extern void debug_cfg_stats (void);
 442 extern void debug_loops (int);
 443 extern void debug_loop (struct loop *, int);
 444 extern void debug_loop_num (unsigned, int);
 445 extern void print_loops (FILE *, int);
 446 extern void print_loops_bb (FILE *, basic_block, int, int);
 447 extern void cleanup_dead_labels (void);
 448 extern void group_case_labels (void);
 449 extern gimple first_stmt (basic_block);
 450 extern gimple last_stmt (basic_block);
 451 extern gimple last_and_only_stmt (basic_block);
 452 extern edge find_taken_edge (basic_block, tree);
 453 extern basic_block label_to_block_fn (struct function *, tree);
 454 #define label_to_block(t) (label_to_block_fn (cfun, t))
 455 extern void notice_special_calls (gimple);
 456 extern void clear_special_calls (void);
 457 extern void verify_stmts (void);
 458 extern void verify_gimple (void);
 459 extern void verify_types_in_gimple_seq (gimple_seq);
 460 extern tree gimple_block_label (basic_block);
 461 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 462 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 463                                         basic_block *);
 464 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 465                                       basic_block *);
 466 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 467                                           VEC(basic_block,heap) **bbs_p);
 468 extern void add_phi_args_after_copy_bb (basic_block);
 469 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 470 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 471 extern bool gimple_purge_dead_eh_edges (basic_block);
 472 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 473 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 474                              tree, tree);
 475 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 476                              tree, tree, tree);
 477 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 478                              tree, tree, tree, tree);
 479 extern void init_empty_tree_cfg (void);
 480 extern void init_empty_tree_cfg_for_function (struct function *);
 481 extern void fold_cond_expr_cond (void);
 482 extern void make_abnormal_goto_edges (basic_block, bool);
 483 extern void replace_uses_by (tree, tree);
 484 extern void start_recording_case_labels (void);
 485 extern void end_recording_case_labels (void);
 486 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 487                                            basic_block, tree);
 488 void remove_edge_and_dominated_blocks (edge);
 489 void mark_virtual_ops_in_bb (basic_block);
 490 bool tree_node_can_be_shared (tree);
 491
 492 /* In tree-cfgcleanup.c  */
 493 extern bitmap cfgcleanup_altered_bbs;
 494 extern bool cleanup_tree_cfg (void);
 495
 496 /* In tree-pretty-print.c.  */
 497 extern void dump_generic_bb (FILE *, basic_block, int, int);
 498 extern int op_code_prio (enum tree_code);
 499 extern int op_prio (const_tree);
 500 extern const char *op_symbol_code (enum tree_code);
 501
 502 /* In tree-dfa.c  */
 503 extern var_ann_t create_var_ann (tree);
 504 extern void renumber_gimple_stmt_uids (void);
 505 extern void renumber_gimple_stmt_uids_in_blocks (basic_block *, int);
 506 extern void dump_dfa_stats (FILE *);
 507 extern void debug_dfa_stats (void);
 508 extern void debug_referenced_vars (void);
 509 extern void dump_referenced_vars (FILE *);
 510 extern void dump_variable (FILE *, tree);
 511 extern void debug_variable (tree);
 512 extern tree get_virtual_var (tree);
 513 extern bool add_referenced_var (tree);
 514 extern void remove_referenced_var (tree);
 515 extern void mark_symbols_for_renaming (gimple);
 516 extern void find_new_referenced_vars (gimple);
 517 extern tree make_rename_temp (tree, const char *);
 518 extern void set_default_def (tree, tree);
 519 extern tree gimple_default_def (struct function *, tree);
 520 extern bool stmt_references_abnormal_ssa_name (gimple);
 521 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
 522                                      HOST_WIDE_INT *, HOST_WIDE_INT *);
 523 extern void find_referenced_vars_in (gimple);
 524
 525 /* In tree-phinodes.c  */
 526 extern void reserve_phi_args_for_new_edge (basic_block);
 527 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 528 extern gimple make_phi_node (tree var, int len);
 529 extern gimple create_phi_node (tree, basic_block);
 530 extern void add_phi_arg (gimple, tree, edge, source_location);
 531 extern void remove_phi_args (edge);
 532 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 533 extern void remove_phi_nodes (basic_block);
 534 extern void init_phinodes (void);
 535 extern void fini_phinodes (void);
 536 extern void release_phi_node (gimple);
 537 #ifdef GATHER_STATISTICS
 538 extern void phinodes_print_statistics (void);
 539 #endif
 540
 541 /* In gimple-low.c  */
 542 extern void record_vars_into (tree, tree);
 543 extern void record_vars (tree);
 544 extern bool block_may_fallthru (const_tree);
 545 extern bool gimple_seq_may_fallthru (gimple_seq);
 546 extern bool gimple_stmt_may_fallthru (gimple);
 547 extern bool gimple_check_call_args (gimple);
 548
 549
 550 /* In tree-ssa.c  */
 551
 552 /* Mapping for redirected edges.  */
 553 struct GTY(()) _edge_var_map {
 554   tree result;                  /* PHI result.  */
 555   tree def;                     /* PHI arg definition.  */
 556   source_location locus;        /* PHI arg location.  */
 557 };
 558 typedef struct _edge_var_map edge_var_map;
 559
 560 DEF_VEC_O(edge_var_map);
 561 DEF_VEC_ALLOC_O(edge_var_map, heap);
 562
 563 /* A vector of var maps.  */
 564 typedef VEC(edge_var_map, heap) *edge_var_map_vector;
 565
 566 extern void init_tree_ssa (struct function *);
 567 extern void redirect_edge_var_map_add (edge, tree, tree, source_location);
 568 extern void redirect_edge_var_map_clear (edge);
 569 extern void redirect_edge_var_map_dup (edge, edge);
 570 extern edge_var_map_vector redirect_edge_var_map_vector (edge);
 571 extern void redirect_edge_var_map_destroy (void);
 572
 573 extern edge ssa_redirect_edge (edge, basic_block);
 574 extern void flush_pending_stmts (edge);
 575 extern void verify_ssa (bool);
 576 extern void delete_tree_ssa (void);
 577 extern bool ssa_undefined_value_p (tree);
 578 extern void warn_uninit (tree, const char *, void *);
 579 extern unsigned int warn_uninitialized_vars (bool);
 580 extern void execute_update_addresses_taken (bool);
 581
 582 /* Call-back function for walk_use_def_chains().  At each reaching
 583    definition, a function with this prototype is called.  */
 584 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *);
 585
 586 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 587
 588 void insert_debug_temps_for_defs (gimple_stmt_iterator *);
 589 void insert_debug_temp_for_var_def (gimple_stmt_iterator *, tree);
 590 void release_defs_bitset (bitmap toremove);
 591
 592 /* In tree-into-ssa.c  */
 593 void update_ssa (unsigned);
 594 void delete_update_ssa (void);
 595 void register_new_name_mapping (tree, tree);
 596 tree create_new_def_for (tree, gimple, def_operand_p);
 597 bool need_ssa_update_p (struct function *);
 598 bool name_mappings_registered_p (void);
 599 bool name_registered_for_update_p (tree);
 600 bitmap ssa_names_to_replace (void);
 601 void release_ssa_name_after_update_ssa (tree);
 602 void compute_global_livein (bitmap, bitmap);
 603 void mark_sym_for_renaming (tree);
 604 void mark_set_for_renaming (bitmap);
 605 tree get_current_def (tree);
 606 void set_current_def (tree, tree);
 607
 608 /* In tree-ssanames.c  */
 609 extern void init_ssanames (struct function *, int);
 610 extern void fini_ssanames (void);
 611 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 612 extern tree duplicate_ssa_name (tree, gimple);
 613 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 614 extern void release_ssa_name (tree);
 615 extern void release_defs (gimple);
 616 extern void replace_ssa_name_symbol (tree, tree);
 617
 618 #ifdef GATHER_STATISTICS
 619 extern void ssanames_print_statistics (void);
 620 #endif
 621
 622 /* In tree-ssa-ccp.c  */
 623 tree fold_const_aggregate_ref (tree);
 624
 625 /* In tree-ssa-dom.c  */
 626 extern void dump_dominator_optimization_stats (FILE *);
 627 extern void debug_dominator_optimization_stats (void);
 628 int loop_depth_of_name (tree);
 629 tree degenerate_phi_result (gimple);
 630
 631 /* In tree-ssa-copy.c  */
 632 extern void propagate_value (use_operand_p, tree);
 633 extern void propagate_tree_value (tree *, tree);
 634 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 635 extern void replace_exp (use_operand_p, tree);
 636 extern bool may_propagate_copy (tree, tree);
 637 extern bool may_propagate_copy_into_stmt (gimple, tree);
 638 extern bool may_propagate_copy_into_asm (tree);
 639
 640 /* Affine iv.  */
 641
 642 typedef struct
 643 {
 644   /* Iv = BASE + STEP * i.  */
 645   tree base, step;
 646
 647   /* True if this iv does not overflow.  */
 648   bool no_overflow;
 649 } affine_iv;
 650
 651 /* Description of number of iterations of a loop.  All the expressions inside
 652    the structure can be evaluated at the end of the loop's preheader
 653    (and due to ssa form, also anywhere inside the body of the loop).  */
 654
 655 struct tree_niter_desc
 656 {
 657   tree assumptions;     /* The boolean expression.  If this expression evaluates
 658                            to false, then the other fields in this structure
 659                            should not be used; there is no guarantee that they
 660                            will be correct.  */
 661   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 662                            the loop will exit in the first iteration (i.e.
 663                            its latch will not be executed), even if the niter
 664                            field says otherwise.  */
 665   tree niter;           /* The expression giving the number of iterations of
 666                            a loop (provided that assumptions == true and
 667                            may_be_zero == false), more precisely the number
 668                            of executions of the latch of the loop.  */
 669   double_int max;       /* The upper bound on the number of iterations of
 670                            the loop.  */
 671
 672   /* The simplified shape of the exit condition.  The loop exits if
 673      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 674      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 675      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 676      by loop unrolling.  */
 677   affine_iv control;
 678   tree bound;
 679   enum tree_code cmp;
 680 };
 681
 682 /* In tree-ssa-phiopt.c */
 683 bool empty_block_p (basic_block);
 684 basic_block *blocks_in_phiopt_order (void);
 685
 686 /* In tree-ssa-loop*.c  */
 687
 688 unsigned int tree_ssa_lim (void);
 689 unsigned int tree_ssa_unswitch_loops (void);
 690 unsigned int canonicalize_induction_variables (void);
 691 unsigned int tree_unroll_loops_completely (bool, bool);
 692 unsigned int tree_ssa_prefetch_arrays (void);
 693 void tree_ssa_iv_optimize (void);
 694 unsigned tree_predictive_commoning (void);
 695 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 696 bool parallelize_loops (void);
 697
 698 bool loop_only_exit_p (const struct loop *, const_edge);
 699 bool number_of_iterations_exit (struct loop *, edge,
 700                                 struct tree_niter_desc *niter, bool);
 701 tree find_loop_niter (struct loop *, edge *);
 702 tree loop_niter_by_eval (struct loop *, edge);
 703 tree find_loop_niter_by_eval (struct loop *, edge *);
 704 void estimate_numbers_of_iterations (void);
 705 bool array_at_struct_end_p (tree);
 706 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 707 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 708
 709 bool nowrap_type_p (tree);
 710 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 711 enum ev_direction scev_direction (const_tree);
 712
 713 void free_numbers_of_iterations_estimates (void);
 714 void free_numbers_of_iterations_estimates_loop (struct loop *);
 715 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 716 void verify_loop_closed_ssa (bool);
 717 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 718 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 719                 tree *, tree *);
 720 basic_block split_loop_exit_edge (edge);
 721 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 722                                      bool *);
 723 basic_block ip_end_pos (struct loop *);
 724 basic_block ip_normal_pos (struct loop *);
 725 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 726                                          unsigned int, sbitmap,
 727                                          edge, VEC (edge, heap) **,
 728                                          int);
 729 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 730 void rename_variables_in_loop (struct loop *);
 731 void rename_variables_in_bb (basic_block bb);
 732 struct loop *tree_ssa_loop_version (struct loop *, tree,
 733                                     basic_block *);
 734 tree expand_simple_operations (tree);
 735 void substitute_in_loop_info (struct loop *, tree, tree);
 736 edge single_dom_exit (struct loop *);
 737 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 738                         struct tree_niter_desc *niter);
 739 void tree_unroll_loop (struct loop *, unsigned,
 740                        edge, struct tree_niter_desc *);
 741 typedef void (*transform_callback)(struct loop *, void *);
 742 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 743                                      edge, struct tree_niter_desc *,
 744                                      transform_callback, void *);
 745 bool contains_abnormal_ssa_name_p (tree);
 746 bool stmt_dominates_stmt_p (gimple, gimple);
 747 void mark_virtual_ops_for_renaming (gimple);
 748
 749 /* In tree-ssa-dce.c */
 750 void mark_virtual_phi_result_for_renaming (gimple);
 751
 752 /* In tree-ssa-threadedge.c */
 753 extern void threadedge_initialize_values (void);
 754 extern void threadedge_finalize_values (void);
 755 extern VEC(tree,heap) *ssa_name_values;
 756 #define SSA_NAME_VALUE(x) \
 757     (SSA_NAME_VERSION(x) < VEC_length(tree, ssa_name_values) \
 758      ? VEC_index(tree, ssa_name_values, SSA_NAME_VERSION(x)) \
 759      : NULL_TREE)
 760 extern void set_ssa_name_value (tree, tree);
 761 extern bool potentially_threadable_block (basic_block);
 762 extern void thread_across_edge (gimple, edge, bool,
 763                                 VEC(tree, heap) **, tree (*) (gimple, gimple));
 764
 765 /* In tree-ssa-loop-im.c  */
 766 /* The possibilities of statement movement.  */
 767
 768 enum move_pos
 769   {
 770     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 771     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 772                                    become executed -- memory accesses, ... */
 773     MOVE_POSSIBLE               /* Unlimited movement.  */
 774   };
 775 extern enum move_pos movement_possibility (gimple);
 776 char *get_lsm_tmp_name (tree, unsigned);
 777
 778 /* In tree-flow-inline.h  */
 779 static inline void set_is_used (tree);
 780 static inline bool unmodifiable_var_p (const_tree);
 781 static inline bool ref_contains_array_ref (const_tree);
 782 static inline bool array_ref_contains_indirect_ref (const_tree);
 783
 784 /* In tree-eh.c  */
 785 extern void make_eh_edges (gimple);
 786 extern bool make_eh_dispatch_edges (gimple);
 787 extern edge redirect_eh_edge (edge, basic_block);
 788 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 789 extern bool tree_could_trap_p (tree);
 790 extern bool operation_could_trap_helper_p (enum tree_code, bool, bool, bool,
 791                                            bool, tree, bool *);
 792 extern bool operation_could_trap_p (enum tree_code, bool, bool, tree);
 793 extern bool stmt_could_throw_p (gimple);
 794 extern bool tree_could_throw_p (tree);
 795 extern bool stmt_can_throw_internal (gimple);
 796 extern bool stmt_can_throw_external (gimple);
 797 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 798 extern void add_stmt_to_eh_lp (gimple, int);
 799 extern bool remove_stmt_from_eh_lp (gimple);
 800 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 801 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 802 extern int lookup_stmt_eh_lp (gimple);
 803 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 804 extern bool maybe_clean_eh_stmt (gimple);
 805 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 806 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 807                                         struct function *, gimple,
 808                                         struct pointer_map_t *, int);
 809 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 810 extern bool verify_eh_edges (gimple);
 811 extern bool verify_eh_dispatch_edge (gimple);
 812
 813 /* In tree-ssa-pre.c  */
 814 struct pre_expr_d;
 815 void add_to_value (unsigned int, struct pre_expr_d *);
 816 void debug_value_expressions (unsigned int);
 817 void print_value_expressions (FILE *, unsigned int);
 818
 819 /* In tree-ssa-sink.c  */
 820 bool is_hidden_global_store (gimple);
 821
 822 /* In tree-loop-linear.c  */
 823 extern void linear_transform_loops (void);
 824 extern unsigned perfect_loop_nest_depth (struct loop *);
 825
 826 /* In graphite.c  */
 827 extern void graphite_transform_loops (void);
 828
 829 /* In tree-data-ref.c  */
 830 extern void tree_check_data_deps (void);
 831
 832 /* In tree-ssa-loop-ivopts.c  */
 833 bool expr_invariant_in_loop_p (struct loop *, tree);
 834 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 835 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 836                                       addr_space_t);
 837 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode, bool);
 838
 839 /* In tree-ssa-threadupdate.c.  */
 840 extern bool thread_through_all_blocks (bool);
 841 extern void register_jump_thread (edge, edge);
 842
 843 /* In gimplify.c  */
 844 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 845 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 846                                bool, enum gsi_iterator_update);
 847 tree gimple_fold_indirect_ref (tree);
 848
 849 /* In tree-ssa-live.c */
 850 extern void remove_unused_locals (void);
 851 extern void dump_scope_blocks (FILE *, int);
 852 extern void debug_scope_blocks (int);
 853 extern void debug_scope_block (tree, int);
 854
 855 /* In tree-ssa-address.c  */
 856
 857 /* Description of a memory address.  */
 858
 859 struct mem_address
 860 {
 861   tree symbol, base, index, step, offset;
 862 };
 863
 864 struct affine_tree_combination;
 865 tree create_mem_ref (gimple_stmt_iterator *, tree,
 866                      struct affine_tree_combination *, tree, bool);
 867 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 868 void get_address_description (tree, struct mem_address *);
 869 tree maybe_fold_tmr (tree);
 870
 871 unsigned int execute_free_datastructures (void);
 872 unsigned int execute_fixup_cfg (void);
 873
 874 #include "tree-flow-inline.h"
 875
 876 void swap_tree_operands (gimple, tree *, tree *);
 877
 878 int least_common_multiple (int, int);
 879
 880 #endif /* _TREE_FLOW_H  */