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 "sbitmap.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   /* Alignment and misalignment of the pointer in bytes.  Together
 124      align and misalign specify low known bits of the pointer.
 125      ptr & (align - 1) == misalign.  */
 126
 127   /* The power-of-two byte alignment of the object this pointer
 128      points into.  This is usually DECL_ALIGN_UNIT for decls and
 129      MALLOC_ABI_ALIGNMENT for allocated storage.  */
 130   unsigned int align;
 131
 132   /* The byte offset this pointer differs from the above alignment.  */
 133   unsigned int misalign;
 134 };
 135
 136
 137 /* It is advantageous to avoid things like life analysis for variables which
 138    do not need PHI nodes.  This enum describes whether or not a particular
 139    variable may need a PHI node.  */
 140
 141 enum need_phi_state {
 142   /* This is the default.  If we are still in this state after finding
 143      all the definition and use sites, then we will assume the variable
 144      needs PHI nodes.  This is probably an overly conservative assumption.  */
 145   NEED_PHI_STATE_UNKNOWN,
 146
 147   /* This state indicates that we have seen one or more sets of the
 148      variable in a single basic block and that the sets dominate all
 149      uses seen so far.  If after finding all definition and use sites
 150      we are still in this state, then the variable does not need any
 151      PHI nodes.  */
 152   NEED_PHI_STATE_NO,
 153
 154   /* This state indicates that we have either seen multiple definitions of
 155      the variable in multiple blocks, or that we encountered a use in a
 156      block that was not dominated by the block containing the set(s) of
 157      this variable.  This variable is assumed to need PHI nodes.  */
 158   NEED_PHI_STATE_MAYBE
 159 };
 160
 161
 162 struct GTY(()) var_ann_d {
 163   /* Used when building base variable structures in a var_map.  */
 164   unsigned base_var_processed : 1;
 165
 166   /* Nonzero if this variable was used after SSA optimizations were
 167      applied.  We set this when translating out of SSA form.  */
 168   unsigned used : 1;
 169
 170   /* This field indicates whether or not the variable may need PHI nodes.
 171      See the enum's definition for more detailed information about the
 172      states.  */
 173   ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
 174
 175   /* True for HEAP artificial variables.  These variables represent
 176      the memory area allocated by a call to malloc.  */
 177   unsigned is_heapvar : 1;
 178
 179   /* Used by var_map for the base index of ssa base variables.  */
 180   unsigned base_index;
 181
 182   /* During into-ssa and the dominator optimizer, this field holds the
 183      current version of this variable (an SSA_NAME).  */
 184   tree current_def;
 185 };
 186
 187
 188 /* Immediate use lists are used to directly access all uses for an SSA
 189    name and get pointers to the statement for each use.
 190
 191    The structure ssa_use_operand_d consists of PREV and NEXT pointers
 192    to maintain the list.  A USE pointer, which points to address where
 193    the use is located and a LOC pointer which can point to the
 194    statement where the use is located, or, in the case of the root
 195    node, it points to the SSA name itself.
 196
 197    The list is anchored by an occurrence of ssa_operand_d *in* the
 198    ssa_name node itself (named 'imm_uses').  This node is uniquely
 199    identified by having a NULL USE pointer. and the LOC pointer
 200    pointing back to the ssa_name node itself.  This node forms the
 201    base for a circular list, and initially this is the only node in
 202    the list.
 203
 204    Fast iteration allows each use to be examined, but does not allow
 205    any modifications to the uses or stmts.
 206
 207    Normal iteration allows insertion, deletion, and modification. the
 208    iterator manages this by inserting a marker node into the list
 209    immediately before the node currently being examined in the list.
 210    this marker node is uniquely identified by having null stmt *and* a
 211    null use pointer.
 212
 213    When iterating to the next use, the iteration routines check to see
 214    if the node after the marker has changed. if it has, then the node
 215    following the marker is now the next one to be visited. if not, the
 216    marker node is moved past that node in the list (visualize it as
 217    bumping the marker node through the list).  this continues until
 218    the marker node is moved to the original anchor position. the
 219    marker node is then removed from the list.
 220
 221    If iteration is halted early, the marker node must be removed from
 222    the list before continuing.  */
 223 typedef struct immediate_use_iterator_d
 224 {
 225   /* This is the current use the iterator is processing.  */
 226   ssa_use_operand_t *imm_use;
 227   /* This marks the last use in the list (use node from SSA_NAME)  */
 228   ssa_use_operand_t *end_p;
 229   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 230   ssa_use_operand_t iter_node;
 231   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 232      the next one is traversed to, so it must be cached early.  */
 233   ssa_use_operand_t *next_imm_name;
 234 } imm_use_iterator;
 235
 236
 237 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 238    modifying stmts will cause this iterator to malfunction.  */
 239
 240 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)               \
 241   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 242        !end_readonly_imm_use_p (&(ITER));                       \
 243        (void) ((DEST) = next_readonly_imm_use (&(ITER))))
 244
 245 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 246
 247 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 248   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 249        !end_imm_use_stmt_p (&(ITER));                           \
 250        (void) ((STMT) = next_imm_use_stmt (&(ITER))))
 251
 252 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 253    do so will result in leaving a iterator marker node in the immediate
 254    use list, and nothing good will come from that.   */
 255 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 256    {                                                            \
 257      end_imm_use_stmt_traverse (&(ITER));                       \
 258      break;                                                     \
 259    }
 260
 261
 262 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 263    get access to each occurrence of ssavar on the stmt returned by
 264    that iterator..  for instance:
 265
 266      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 267        {
 268          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 269            {
 270              SET_USE (use_p, blah);
 271            }
 272          update_stmt (stmt);
 273        }                                                         */
 274
 275 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 276   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 277        !end_imm_use_on_stmt_p (&(ITER));                        \
 278        (void) ((DEST) = next_imm_use_on_stmt (&(ITER))))
 279
 280
 281
 282 typedef struct var_ann_d *var_ann_t;
 283
 284 static inline var_ann_t var_ann (const_tree);
 285 static inline var_ann_t get_var_ann (tree);
 286 static inline void update_stmt (gimple);
 287 static inline int get_lineno (const_gimple);
 288
 289 /* Accessors for basic block annotations.  */
 290 static inline gimple_seq phi_nodes (const_basic_block);
 291 static inline void set_phi_nodes (basic_block, gimple_seq);
 292
 293 /*---------------------------------------------------------------------------
 294                               Global declarations
 295 ---------------------------------------------------------------------------*/
 296 struct int_tree_map {
 297   unsigned int uid;
 298   tree to;
 299 };
 300
 301 extern unsigned int int_tree_map_hash (const void *);
 302 extern int int_tree_map_eq (const void *, const void *);
 303
 304 extern unsigned int uid_decl_map_hash (const void *);
 305 extern int uid_decl_map_eq (const void *, const void *);
 306
 307 typedef struct
 308 {
 309   htab_iterator hti;
 310 } referenced_var_iterator;
 311
 312 /* This macro loops over all the referenced vars, one at a time, putting the
 313    current var in VAR.  Note:  You are not allowed to add referenced variables
 314    to the hashtable while using this macro.  Doing so may cause it to behave
 315    erratically.  */
 316
 317 #define FOR_EACH_REFERENCED_VAR(VAR, ITER) \
 318   for ((VAR) = first_referenced_var (&(ITER)); \
 319        !end_referenced_vars_p (&(ITER)); \
 320        (VAR) = next_referenced_var (&(ITER)))
 321
 322 extern tree referenced_var_lookup (unsigned int);
 323 extern bool referenced_var_check_and_insert (tree);
 324 #define num_referenced_vars htab_elements (gimple_referenced_vars (cfun))
 325
 326 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
 327 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
 328
 329 /* Macros for showing usage statistics.  */
 330 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 331                   ? (x)                                 \
 332                   : ((x) < 1024*1024*10                 \
 333                      ? (x) / 1024                       \
 334                      : (x) / (1024*1024))))
 335
 336 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 337
 338 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 339
 340 /*---------------------------------------------------------------------------
 341                               OpenMP Region Tree
 342 ---------------------------------------------------------------------------*/
 343
 344 /* Parallel region information.  Every parallel and workshare
 345    directive is enclosed between two markers, the OMP_* directive
 346    and a corresponding OMP_RETURN statement.  */
 347
 348 struct omp_region
 349 {
 350   /* The enclosing region.  */
 351   struct omp_region *outer;
 352
 353   /* First child region.  */
 354   struct omp_region *inner;
 355
 356   /* Next peer region.  */
 357   struct omp_region *next;
 358
 359   /* Block containing the omp directive as its last stmt.  */
 360   basic_block entry;
 361
 362   /* Block containing the OMP_RETURN as its last stmt.  */
 363   basic_block exit;
 364
 365   /* Block containing the OMP_CONTINUE as its last stmt.  */
 366   basic_block cont;
 367
 368   /* If this is a combined parallel+workshare region, this is a list
 369      of additional arguments needed by the combined parallel+workshare
 370      library call.  */
 371   VEC(tree,gc) *ws_args;
 372
 373   /* The code for the omp directive of this region.  */
 374   enum gimple_code type;
 375
 376   /* Schedule kind, only used for OMP_FOR type regions.  */
 377   enum omp_clause_schedule_kind sched_kind;
 378
 379   /* True if this is a combined parallel+workshare region.  */
 380   bool is_combined_parallel;
 381 };
 382
 383 extern struct omp_region *root_omp_region;
 384 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 385                                           struct omp_region *);
 386 extern void free_omp_regions (void);
 387 void omp_expand_local (basic_block);
 388 extern tree find_omp_clause (tree, enum omp_clause_code);
 389 tree copy_var_decl (tree, tree, tree);
 390
 391 /*---------------------------------------------------------------------------
 392                               Function prototypes
 393 ---------------------------------------------------------------------------*/
 394 /* In tree-cfg.c  */
 395
 396 /* Location to track pending stmt for edge insertion.  */
 397 #define PENDING_STMT(e) ((e)->insns.g)
 398
 399 extern void delete_tree_cfg_annotations (void);
 400 extern bool stmt_ends_bb_p (gimple);
 401 extern bool is_ctrl_stmt (gimple);
 402 extern bool is_ctrl_altering_stmt (gimple);
 403 extern bool simple_goto_p (gimple);
 404 extern bool stmt_can_make_abnormal_goto (gimple);
 405 extern basic_block single_noncomplex_succ (basic_block bb);
 406 extern void gimple_dump_bb (basic_block, FILE *, int, int);
 407 extern void gimple_debug_bb (basic_block);
 408 extern basic_block gimple_debug_bb_n (int);
 409 extern void gimple_dump_cfg (FILE *, int);
 410 extern void gimple_debug_cfg (int);
 411 extern void dump_cfg_stats (FILE *);
 412 extern void dot_cfg (void);
 413 extern void debug_cfg_stats (void);
 414 extern void debug_loops (int);
 415 extern void debug_loop (struct loop *, int);
 416 extern void debug_loop_num (unsigned, int);
 417 extern void print_loops (FILE *, int);
 418 extern void print_loops_bb (FILE *, basic_block, int, int);
 419 extern void cleanup_dead_labels (void);
 420 extern void group_case_labels (void);
 421 extern gimple first_stmt (basic_block);
 422 extern gimple last_stmt (basic_block);
 423 extern gimple last_and_only_stmt (basic_block);
 424 extern edge find_taken_edge (basic_block, tree);
 425 extern basic_block label_to_block_fn (struct function *, tree);
 426 #define label_to_block(t) (label_to_block_fn (cfun, t))
 427 extern void notice_special_calls (gimple);
 428 extern void clear_special_calls (void);
 429 extern void verify_stmts (void);
 430 extern void verify_gimple (void);
 431 extern void verify_types_in_gimple_seq (gimple_seq);
 432 extern tree gimple_block_label (basic_block);
 433 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 434 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 435                                         basic_block *);
 436 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 437                                       basic_block *);
 438 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 439                                           VEC(basic_block,heap) **bbs_p);
 440 extern void add_phi_args_after_copy_bb (basic_block);
 441 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 442 extern bool gimple_purge_dead_eh_edges (basic_block);
 443 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 444 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 445 extern bool gimple_purge_all_dead_abnormal_call_edges (const_bitmap);
 446 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 447                              tree, tree);
 448 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 449                              tree, tree, tree);
 450 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 451                              tree, tree, tree, tree);
 452 extern void init_empty_tree_cfg (void);
 453 extern void init_empty_tree_cfg_for_function (struct function *);
 454 extern void fold_cond_expr_cond (void);
 455 extern void make_abnormal_goto_edges (basic_block, bool);
 456 extern void replace_uses_by (tree, tree);
 457 extern void start_recording_case_labels (void);
 458 extern void end_recording_case_labels (void);
 459 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 460                                            basic_block, tree);
 461 void remove_edge_and_dominated_blocks (edge);
 462 bool tree_node_can_be_shared (tree);
 463
 464 /* In tree-cfgcleanup.c  */
 465 extern bitmap cfgcleanup_altered_bbs;
 466 extern bool cleanup_tree_cfg (void);
 467
 468 /* In tree-pretty-print.c.  */
 469 extern void dump_generic_bb (FILE *, basic_block, int, int);
 470 extern int op_code_prio (enum tree_code);
 471 extern int op_prio (const_tree);
 472 extern const char *op_symbol_code (enum tree_code);
 473
 474 /* In tree-dfa.c  */
 475 extern var_ann_t create_var_ann (tree);
 476 extern void renumber_gimple_stmt_uids (void);
 477 extern void renumber_gimple_stmt_uids_in_blocks (basic_block *, int);
 478 extern void dump_dfa_stats (FILE *);
 479 extern void debug_dfa_stats (void);
 480 extern void debug_referenced_vars (void);
 481 extern void dump_referenced_vars (FILE *);
 482 extern void dump_variable (FILE *, tree);
 483 extern void debug_variable (tree);
 484 extern tree get_virtual_var (tree);
 485 extern bool add_referenced_var (tree);
 486 extern void remove_referenced_var (tree);
 487 extern void mark_symbols_for_renaming (gimple);
 488 extern void find_new_referenced_vars (gimple);
 489 extern tree make_rename_temp (tree, const char *);
 490 extern void set_default_def (tree, tree);
 491 extern tree gimple_default_def (struct function *, tree);
 492 extern bool stmt_references_abnormal_ssa_name (gimple);
 493 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
 494                                      HOST_WIDE_INT *, HOST_WIDE_INT *);
 495 extern tree get_addr_base_and_unit_offset (tree, HOST_WIDE_INT *);
 496 extern void find_referenced_vars_in (gimple);
 497
 498 /* In tree-phinodes.c  */
 499 extern void reserve_phi_args_for_new_edge (basic_block);
 500 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 501 extern gimple make_phi_node (tree var, int len);
 502 extern gimple create_phi_node (tree, basic_block);
 503 extern void add_phi_arg (gimple, tree, edge, source_location);
 504 extern void remove_phi_args (edge);
 505 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 506 extern void remove_phi_nodes (basic_block);
 507 extern void init_phinodes (void);
 508 extern void fini_phinodes (void);
 509 extern void release_phi_node (gimple);
 510 #ifdef GATHER_STATISTICS
 511 extern void phinodes_print_statistics (void);
 512 #endif
 513
 514 /* In gimple-low.c  */
 515 extern void record_vars_into (tree, tree);
 516 extern void record_vars (tree);
 517 extern bool gimple_seq_may_fallthru (gimple_seq);
 518 extern bool gimple_stmt_may_fallthru (gimple);
 519 extern bool gimple_check_call_args (gimple);
 520
 521
 522 /* In tree-ssa.c  */
 523
 524 /* Mapping for redirected edges.  */
 525 struct _edge_var_map {
 526   tree result;                  /* PHI result.  */
 527   tree def;                     /* PHI arg definition.  */
 528   source_location locus;        /* PHI arg location.  */
 529 };
 530 typedef struct _edge_var_map edge_var_map;
 531
 532 DEF_VEC_O(edge_var_map);
 533 DEF_VEC_ALLOC_O(edge_var_map, heap);
 534
 535 /* A vector of var maps.  */
 536 typedef VEC(edge_var_map, heap) *edge_var_map_vector;
 537
 538 extern void init_tree_ssa (struct function *);
 539 extern void redirect_edge_var_map_add (edge, tree, tree, source_location);
 540 extern void redirect_edge_var_map_clear (edge);
 541 extern void redirect_edge_var_map_dup (edge, edge);
 542 extern edge_var_map_vector redirect_edge_var_map_vector (edge);
 543 extern void redirect_edge_var_map_destroy (void);
 544
 545 extern edge ssa_redirect_edge (edge, basic_block);
 546 extern void flush_pending_stmts (edge);
 547 extern void verify_ssa (bool);
 548 extern void delete_tree_ssa (void);
 549 extern bool ssa_undefined_value_p (tree);
 550 extern void warn_uninit (tree, const char *, void *);
 551 extern unsigned int warn_uninitialized_vars (bool);
 552 extern void execute_update_addresses_taken (void);
 553
 554 /* Call-back function for walk_use_def_chains().  At each reaching
 555    definition, a function with this prototype is called.  */
 556 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *);
 557
 558 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 559
 560 void insert_debug_temps_for_defs (gimple_stmt_iterator *);
 561 void insert_debug_temp_for_var_def (gimple_stmt_iterator *, tree);
 562 void release_defs_bitset (bitmap toremove);
 563
 564 /* In tree-into-ssa.c  */
 565 void update_ssa (unsigned);
 566 void delete_update_ssa (void);
 567 void register_new_name_mapping (tree, tree);
 568 tree create_new_def_for (tree, gimple, def_operand_p);
 569 bool need_ssa_update_p (struct function *);
 570 bool name_mappings_registered_p (void);
 571 bool name_registered_for_update_p (tree);
 572 bitmap ssa_names_to_replace (void);
 573 void release_ssa_name_after_update_ssa (tree);
 574 void compute_global_livein (bitmap, bitmap);
 575 void mark_sym_for_renaming (tree);
 576 void mark_set_for_renaming (bitmap);
 577 bool symbol_marked_for_renaming (tree);
 578 tree get_current_def (tree);
 579 void set_current_def (tree, tree);
 580
 581 /* In tree-ssanames.c  */
 582 extern void init_ssanames (struct function *, int);
 583 extern void fini_ssanames (void);
 584 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 585 extern tree duplicate_ssa_name (tree, gimple);
 586 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 587 extern void release_ssa_name (tree);
 588 extern void release_defs (gimple);
 589 extern void replace_ssa_name_symbol (tree, tree);
 590
 591 #ifdef GATHER_STATISTICS
 592 extern void ssanames_print_statistics (void);
 593 #endif
 594
 595 /* In tree-ssa-ccp.c  */
 596 tree fold_const_aggregate_ref (tree);
 597
 598 /* In tree-ssa-dom.c  */
 599 extern void dump_dominator_optimization_stats (FILE *);
 600 extern void debug_dominator_optimization_stats (void);
 601 int loop_depth_of_name (tree);
 602 tree degenerate_phi_result (gimple);
 603
 604 /* In tree-ssa-copy.c  */
 605 extern void propagate_value (use_operand_p, tree);
 606 extern void propagate_tree_value (tree *, tree);
 607 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 608 extern void replace_exp (use_operand_p, tree);
 609 extern bool may_propagate_copy (tree, tree);
 610 extern bool may_propagate_copy_into_stmt (gimple, tree);
 611 extern bool may_propagate_copy_into_asm (tree);
 612
 613 /* Affine iv.  */
 614
 615 typedef struct
 616 {
 617   /* Iv = BASE + STEP * i.  */
 618   tree base, step;
 619
 620   /* True if this iv does not overflow.  */
 621   bool no_overflow;
 622 } affine_iv;
 623
 624 /* Description of number of iterations of a loop.  All the expressions inside
 625    the structure can be evaluated at the end of the loop's preheader
 626    (and due to ssa form, also anywhere inside the body of the loop).  */
 627
 628 struct tree_niter_desc
 629 {
 630   tree assumptions;     /* The boolean expression.  If this expression evaluates
 631                            to false, then the other fields in this structure
 632                            should not be used; there is no guarantee that they
 633                            will be correct.  */
 634   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 635                            the loop will exit in the first iteration (i.e.
 636                            its latch will not be executed), even if the niter
 637                            field says otherwise.  */
 638   tree niter;           /* The expression giving the number of iterations of
 639                            a loop (provided that assumptions == true and
 640                            may_be_zero == false), more precisely the number
 641                            of executions of the latch of the loop.  */
 642   double_int max;       /* The upper bound on the number of iterations of
 643                            the loop.  */
 644
 645   /* The simplified shape of the exit condition.  The loop exits if
 646      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 647      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 648      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 649      by loop unrolling.  */
 650   affine_iv control;
 651   tree bound;
 652   enum tree_code cmp;
 653 };
 654
 655 /* In tree-ssa-phiopt.c */
 656 bool empty_block_p (basic_block);
 657 basic_block *blocks_in_phiopt_order (void);
 658
 659 /* In tree-ssa-loop*.c  */
 660
 661 unsigned int tree_ssa_lim (void);
 662 unsigned int tree_ssa_unswitch_loops (void);
 663 unsigned int canonicalize_induction_variables (void);
 664 unsigned int tree_unroll_loops_completely (bool, bool);
 665 unsigned int tree_ssa_prefetch_arrays (void);
 666 void tree_ssa_iv_optimize (void);
 667 unsigned tree_predictive_commoning (void);
 668 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 669 bool parallelize_loops (void);
 670
 671 bool loop_only_exit_p (const struct loop *, const_edge);
 672 bool number_of_iterations_exit (struct loop *, edge,
 673                                 struct tree_niter_desc *niter, bool);
 674 tree find_loop_niter (struct loop *, edge *);
 675 tree loop_niter_by_eval (struct loop *, edge);
 676 tree find_loop_niter_by_eval (struct loop *, edge *);
 677 void estimate_numbers_of_iterations (bool);
 678 bool array_at_struct_end_p (tree);
 679 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 680 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 681
 682 bool nowrap_type_p (tree);
 683 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 684 enum ev_direction scev_direction (const_tree);
 685
 686 void free_numbers_of_iterations_estimates (void);
 687 void free_numbers_of_iterations_estimates_loop (struct loop *);
 688 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 689 void verify_loop_closed_ssa (bool);
 690 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 691 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 692                 tree *, tree *);
 693 basic_block split_loop_exit_edge (edge);
 694 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 695                                      bool *);
 696 basic_block ip_end_pos (struct loop *);
 697 basic_block ip_normal_pos (struct loop *);
 698 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 699                                          unsigned int, sbitmap,
 700                                          edge, VEC (edge, heap) **,
 701                                          int);
 702 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 703 void rename_variables_in_loop (struct loop *);
 704 void rename_variables_in_bb (basic_block bb);
 705 struct loop *tree_ssa_loop_version (struct loop *, tree,
 706                                     basic_block *);
 707 tree expand_simple_operations (tree);
 708 void substitute_in_loop_info (struct loop *, tree, tree);
 709 edge single_dom_exit (struct loop *);
 710 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 711                         struct tree_niter_desc *niter);
 712 void tree_unroll_loop (struct loop *, unsigned,
 713                        edge, struct tree_niter_desc *);
 714 typedef void (*transform_callback)(struct loop *, void *);
 715 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 716                                      edge, struct tree_niter_desc *,
 717                                      transform_callback, void *);
 718 bool contains_abnormal_ssa_name_p (tree);
 719 bool stmt_dominates_stmt_p (gimple, gimple);
 720 void mark_virtual_ops_for_renaming (gimple);
 721
 722 /* In tree-ssa-dce.c */
 723 void mark_virtual_phi_result_for_renaming (gimple);
 724
 725 /* In tree-ssa-threadedge.c */
 726 extern void threadedge_initialize_values (void);
 727 extern void threadedge_finalize_values (void);
 728 extern VEC(tree,heap) *ssa_name_values;
 729 #define SSA_NAME_VALUE(x) \
 730     (SSA_NAME_VERSION(x) < VEC_length(tree, ssa_name_values) \
 731      ? VEC_index(tree, ssa_name_values, SSA_NAME_VERSION(x)) \
 732      : NULL_TREE)
 733 extern void set_ssa_name_value (tree, tree);
 734 extern bool potentially_threadable_block (basic_block);
 735 extern void thread_across_edge (gimple, edge, bool,
 736                                 VEC(tree, heap) **, tree (*) (gimple, gimple));
 737
 738 /* In tree-ssa-loop-im.c  */
 739 /* The possibilities of statement movement.  */
 740
 741 enum move_pos
 742   {
 743     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 744     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 745                                    become executed -- memory accesses, ... */
 746     MOVE_POSSIBLE               /* Unlimited movement.  */
 747   };
 748 extern enum move_pos movement_possibility (gimple);
 749 char *get_lsm_tmp_name (tree, unsigned);
 750
 751 /* In tree-flow-inline.h  */
 752 static inline void set_is_used (tree);
 753 static inline bool unmodifiable_var_p (const_tree);
 754 static inline bool ref_contains_array_ref (const_tree);
 755
 756 /* In tree-eh.c  */
 757 extern void make_eh_edges (gimple);
 758 extern bool make_eh_dispatch_edges (gimple);
 759 extern edge redirect_eh_edge (edge, basic_block);
 760 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 761 extern bool tree_could_trap_p (tree);
 762 extern bool operation_could_trap_helper_p (enum tree_code, bool, bool, bool,
 763                                            bool, tree, bool *);
 764 extern bool operation_could_trap_p (enum tree_code, bool, bool, tree);
 765 extern bool stmt_could_throw_p (gimple);
 766 extern bool tree_could_throw_p (tree);
 767 extern bool stmt_can_throw_internal (gimple);
 768 extern bool stmt_can_throw_external (gimple);
 769 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 770 extern void add_stmt_to_eh_lp (gimple, int);
 771 extern bool remove_stmt_from_eh_lp (gimple);
 772 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 773 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 774 extern int lookup_stmt_eh_lp (gimple);
 775 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 776 extern bool maybe_clean_eh_stmt (gimple);
 777 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 778 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 779                                         struct function *, gimple,
 780                                         struct pointer_map_t *, int);
 781 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 782 extern bool verify_eh_edges (gimple);
 783 extern bool verify_eh_dispatch_edge (gimple);
 784
 785 /* In tree-ssa-pre.c  */
 786 struct pre_expr_d;
 787 void add_to_value (unsigned int, struct pre_expr_d *);
 788 void debug_value_expressions (unsigned int);
 789 void print_value_expressions (FILE *, unsigned int);
 790
 791 /* In tree-ssa-sink.c  */
 792 bool is_hidden_global_store (gimple);
 793
 794 /* In tree-loop-linear.c  */
 795 extern void linear_transform_loops (void);
 796 extern unsigned perfect_loop_nest_depth (struct loop *);
 797
 798 /* In graphite.c  */
 799 extern void graphite_transform_loops (void);
 800
 801 /* In tree-data-ref.c  */
 802 extern void tree_check_data_deps (void);
 803
 804 /* In tree-ssa-loop-ivopts.c  */
 805 bool expr_invariant_in_loop_p (struct loop *, tree);
 806 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 807 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 808                                       addr_space_t);
 809 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode, bool);
 810 bool may_be_nonaddressable_p (tree expr);
 811
 812 /* In tree-ssa-threadupdate.c.  */
 813 extern bool thread_through_all_blocks (bool);
 814 extern void register_jump_thread (edge, edge);
 815
 816 /* In gimplify.c  */
 817 tree force_gimple_operand_1 (tree, gimple_seq *, gimple_predicate, tree);
 818 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 819 tree force_gimple_operand_gsi_1 (gimple_stmt_iterator *, tree,
 820                                  gimple_predicate, tree,
 821                                  bool, enum gsi_iterator_update);
 822 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 823                                bool, enum gsi_iterator_update);
 824 tree gimple_fold_indirect_ref (tree);
 825
 826 /* In tree-ssa-live.c */
 827 extern void remove_unused_locals (void);
 828 extern void dump_scope_blocks (FILE *, int);
 829 extern void debug_scope_blocks (int);
 830 extern void debug_scope_block (tree, int);
 831
 832 /* In tree-ssa-address.c  */
 833
 834 /* Description of a memory address.  */
 835
 836 struct mem_address
 837 {
 838   tree symbol, base, index, step, offset;
 839 };
 840
 841 struct affine_tree_combination;
 842 tree create_mem_ref (gimple_stmt_iterator *, tree,
 843                      struct affine_tree_combination *, tree, tree, tree, bool);
 844 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 845 void get_address_description (tree, struct mem_address *);
 846 tree maybe_fold_tmr (tree);
 847
 848 unsigned int execute_free_datastructures (void);
 849 unsigned int execute_fixup_cfg (void);
 850 bool fixup_noreturn_call (gimple stmt);
 851
 852 /* In ipa-pure-const.c  */
 853 void warn_function_noreturn (tree);
 854
 855 #include "tree-flow-inline.h"
 856
 857 void swap_tree_operands (gimple, tree *, tree *);
 858
 859 int least_common_multiple (int, int);
 860
 861 #endif /* _TREE_FLOW_H  */