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   /* Artificial variable used to model the effects of nonlocal
  57      variables.  */
  58   tree nonlocal_all;
  59
  60   /* The PTA solution for the ESCAPED artificial variable.  */
  61   struct pt_solution escaped;
  62
  63   /* The PTA solution for the CALLUSED artificial variable.  */
  64   struct pt_solution callused;
  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 /*---------------------------------------------------------------------------
 125                    Tree annotations stored in tree_base.ann
 126 ---------------------------------------------------------------------------*/
 127 enum tree_ann_type { TREE_ANN_COMMON, VAR_ANN, FUNCTION_ANN };
 128
 129 struct GTY(()) tree_ann_common_d {
 130   /* Annotation type.  */
 131   enum tree_ann_type type;
 132
 133   /* Record EH region number into a statement tree created during RTL
 134      expansion (see gimple_to_tree).  */
 135   int rn;
 136
 137   /* Pointer to original GIMPLE statement.  Used during RTL expansion
 138      (see gimple_to_tree).  */
 139   gimple stmt;
 140 };
 141
 142 /* It is advantageous to avoid things like life analysis for variables which
 143    do not need PHI nodes.  This enum describes whether or not a particular
 144    variable may need a PHI node.  */
 145
 146 enum need_phi_state {
 147   /* This is the default.  If we are still in this state after finding
 148      all the definition and use sites, then we will assume the variable
 149      needs PHI nodes.  This is probably an overly conservative assumption.  */
 150   NEED_PHI_STATE_UNKNOWN,
 151
 152   /* This state indicates that we have seen one or more sets of the
 153      variable in a single basic block and that the sets dominate all
 154      uses seen so far.  If after finding all definition and use sites
 155      we are still in this state, then the variable does not need any
 156      PHI nodes.  */
 157   NEED_PHI_STATE_NO,
 158
 159   /* This state indicates that we have either seen multiple definitions of
 160      the variable in multiple blocks, or that we encountered a use in a
 161      block that was not dominated by the block containing the set(s) of
 162      this variable.  This variable is assumed to need PHI nodes.  */
 163   NEED_PHI_STATE_MAYBE
 164 };
 165
 166
 167 /* The "no alias" attribute allows alias analysis to make more
 168    aggressive assumptions when assigning alias sets, computing
 169    points-to information and memory partitions.  These attributes
 170    are the result of user annotations or flags (e.g.,
 171    -fargument-noalias).  */
 172 enum noalias_state {
 173     /* Default state.  No special assumptions can be made about this
 174        symbol.  */
 175     MAY_ALIAS = 0,
 176
 177     /* The symbol does not alias with other symbols that have a
 178        NO_ALIAS* attribute.  */
 179     NO_ALIAS,
 180
 181     /* The symbol does not alias with other symbols that have a
 182        NO_ALIAS*, and it may not alias with global symbols.  */
 183     NO_ALIAS_GLOBAL,
 184
 185     /* The symbol does not alias with any other symbols.  */
 186     NO_ALIAS_ANYTHING
 187 };
 188
 189
 190 struct GTY(()) var_ann_d {
 191   struct tree_ann_common_d common;
 192
 193   /* Used when building base variable structures in a var_map.  */
 194   unsigned base_var_processed : 1;
 195
 196   /* Nonzero if this variable was used after SSA optimizations were
 197      applied.  We set this when translating out of SSA form.  */
 198   unsigned used : 1;
 199
 200   /* This field indicates whether or not the variable may need PHI nodes.
 201      See the enum's definition for more detailed information about the
 202      states.  */
 203   ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
 204
 205   /* True for HEAP artificial variables.  These variables represent
 206      the memory area allocated by a call to malloc.  */
 207   unsigned is_heapvar : 1;
 208
 209   /* This field describes several "no alias" attributes that some
 210      symbols are known to have.  See the enum's definition for more
 211      information on each attribute.  */
 212   ENUM_BITFIELD (noalias_state) noalias_state : 2;
 213
 214   /* Used by var_map for the base index of ssa base variables.  */
 215   unsigned base_index;
 216
 217   /* During into-ssa and the dominator optimizer, this field holds the
 218      current version of this variable (an SSA_NAME).  */
 219   tree current_def;
 220 };
 221
 222
 223 /* Immediate use lists are used to directly access all uses for an SSA
 224    name and get pointers to the statement for each use.
 225
 226    The structure ssa_use_operand_d consists of PREV and NEXT pointers
 227    to maintain the list.  A USE pointer, which points to address where
 228    the use is located and a LOC pointer which can point to the
 229    statement where the use is located, or, in the case of the root
 230    node, it points to the SSA name itself.
 231
 232    The list is anchored by an occurrence of ssa_operand_d *in* the
 233    ssa_name node itself (named 'imm_uses').  This node is uniquely
 234    identified by having a NULL USE pointer. and the LOC pointer
 235    pointing back to the ssa_name node itself.  This node forms the
 236    base for a circular list, and initially this is the only node in
 237    the list.
 238
 239    Fast iteration allows each use to be examined, but does not allow
 240    any modifications to the uses or stmts.
 241
 242    Normal iteration allows insertion, deletion, and modification. the
 243    iterator manages this by inserting a marker node into the list
 244    immediately before the node currently being examined in the list.
 245    this marker node is uniquely identified by having null stmt *and* a
 246    null use pointer.
 247
 248    When iterating to the next use, the iteration routines check to see
 249    if the node after the marker has changed. if it has, then the node
 250    following the marker is now the next one to be visited. if not, the
 251    marker node is moved past that node in the list (visualize it as
 252    bumping the marker node through the list).  this continues until
 253    the marker node is moved to the original anchor position. the
 254    marker node is then removed from the list.
 255
 256    If iteration is halted early, the marker node must be removed from
 257    the list before continuing.  */
 258 typedef struct immediate_use_iterator_d
 259 {
 260   /* This is the current use the iterator is processing.  */
 261   ssa_use_operand_t *imm_use;
 262   /* This marks the last use in the list (use node from SSA_NAME)  */
 263   ssa_use_operand_t *end_p;
 264   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 265   ssa_use_operand_t iter_node;
 266   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 267      the next one is traversed to, so it must be cached early.  */
 268   ssa_use_operand_t *next_imm_name;
 269 } imm_use_iterator;
 270
 271
 272 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 273    modifying stmts will cause this iterator to malfunction.  */
 274
 275 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)                       \
 276   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 277        !end_readonly_imm_use_p (&(ITER));                       \
 278        (DEST) = next_readonly_imm_use (&(ITER)))
 279
 280 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 281
 282 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 283   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 284        !end_imm_use_stmt_p (&(ITER));                           \
 285        (STMT) = next_imm_use_stmt (&(ITER)))
 286
 287 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 288    do so will result in leaving a iterator marker node in the immediate
 289    use list, and nothing good will come from that.   */
 290 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 291    {                                                            \
 292      end_imm_use_stmt_traverse (&(ITER));                       \
 293      break;                                                     \
 294    }
 295
 296
 297 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 298    get access to each occurrence of ssavar on the stmt returned by
 299    that iterator..  for instance:
 300
 301      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 302        {
 303          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 304            {
 305              SET_USE (use_p, blah);
 306            }
 307          update_stmt (stmt);
 308        }                                                         */
 309
 310 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 311   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 312        !end_imm_use_on_stmt_p (&(ITER));                        \
 313        (DEST) = next_imm_use_on_stmt (&(ITER)))
 314
 315
 316
 317 union GTY((desc ("ann_type ((tree_ann_t)&%h)"))) tree_ann_d {
 318   struct tree_ann_common_d GTY((tag ("TREE_ANN_COMMON"))) common;
 319   struct var_ann_d GTY((tag ("VAR_ANN"))) vdecl;
 320 };
 321
 322 typedef union tree_ann_d *tree_ann_t;
 323 typedef struct var_ann_d *var_ann_t;
 324 typedef struct tree_ann_common_d *tree_ann_common_t;
 325
 326 static inline tree_ann_common_t tree_common_ann (const_tree);
 327 static inline tree_ann_common_t get_tree_common_ann (tree);
 328 static inline var_ann_t var_ann (const_tree);
 329 static inline var_ann_t get_var_ann (tree);
 330 static inline enum tree_ann_type ann_type (tree_ann_t);
 331 static inline void update_stmt (gimple);
 332 static inline int get_lineno (const_gimple);
 333
 334 /*---------------------------------------------------------------------------
 335                   Structure representing predictions in tree level.
 336 ---------------------------------------------------------------------------*/
 337 struct GTY((chain_next ("%h.ep_next"))) edge_prediction {
 338   struct edge_prediction *ep_next;
 339   edge ep_edge;
 340   enum br_predictor ep_predictor;
 341   int ep_probability;
 342 };
 343
 344 /* Accessors for basic block annotations.  */
 345 static inline gimple_seq phi_nodes (const_basic_block);
 346 static inline void set_phi_nodes (basic_block, gimple_seq);
 347
 348 /*---------------------------------------------------------------------------
 349                               Global declarations
 350 ---------------------------------------------------------------------------*/
 351 struct GTY(()) int_tree_map {
 352
 353   unsigned int uid;
 354   tree to;
 355 };
 356
 357 extern unsigned int int_tree_map_hash (const void *);
 358 extern int int_tree_map_eq (const void *, const void *);
 359
 360 extern unsigned int uid_decl_map_hash (const void *);
 361 extern int uid_decl_map_eq (const void *, const void *);
 362
 363 typedef struct
 364 {
 365   htab_iterator hti;
 366 } referenced_var_iterator;
 367
 368
 369 /* This macro loops over all the referenced vars, one at a time, putting the
 370    current var in VAR.  Note:  You are not allowed to add referenced variables
 371    to the hashtable while using this macro.  Doing so may cause it to behave
 372    erratically.  */
 373
 374 #define FOR_EACH_REFERENCED_VAR(VAR, ITER) \
 375   for ((VAR) = first_referenced_var (&(ITER)); \
 376        !end_referenced_vars_p (&(ITER)); \
 377        (VAR) = next_referenced_var (&(ITER)))
 378
 379
 380 typedef struct
 381 {
 382   int i;
 383 } safe_referenced_var_iterator;
 384
 385 /* This macro loops over all the referenced vars, one at a time, putting the
 386    current var in VAR.  You are allowed to add referenced variables during the
 387    execution of this macro, however, the macro will not iterate over them.  It
 388    requires a temporary vector of trees, VEC, whose lifetime is controlled by
 389    the caller.  The purpose of the vector is to temporarily store the
 390    referenced_variables hashtable so that adding referenced variables does not
 391    affect the hashtable.  */
 392
 393 #define FOR_EACH_REFERENCED_VAR_SAFE(VAR, VEC, ITER) \
 394   for ((ITER).i = 0, fill_referenced_var_vec (&(VEC)); \
 395        VEC_iterate (tree, (VEC), (ITER).i, (VAR)); \
 396        (ITER).i++)
 397
 398 extern tree referenced_var_lookup (unsigned int);
 399 extern bool referenced_var_check_and_insert (tree);
 400 #define num_referenced_vars htab_elements (gimple_referenced_vars (cfun))
 401 #define referenced_var(i) referenced_var_lookup (i)
 402
 403 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
 404 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
 405
 406 /* Macros for showing usage statistics.  */
 407 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 408                   ? (x)                                 \
 409                   : ((x) < 1024*1024*10                 \
 410                      ? (x) / 1024                       \
 411                      : (x) / (1024*1024))))
 412
 413 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 414
 415 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 416
 417 /*---------------------------------------------------------------------------
 418                               OpenMP Region Tree
 419 ---------------------------------------------------------------------------*/
 420
 421 /* Parallel region information.  Every parallel and workshare
 422    directive is enclosed between two markers, the OMP_* directive
 423    and a corresponding OMP_RETURN statement.  */
 424
 425 struct omp_region
 426 {
 427   /* The enclosing region.  */
 428   struct omp_region *outer;
 429
 430   /* First child region.  */
 431   struct omp_region *inner;
 432
 433   /* Next peer region.  */
 434   struct omp_region *next;
 435
 436   /* Block containing the omp directive as its last stmt.  */
 437   basic_block entry;
 438
 439   /* Block containing the OMP_RETURN as its last stmt.  */
 440   basic_block exit;
 441
 442   /* Block containing the OMP_CONTINUE as its last stmt.  */
 443   basic_block cont;
 444
 445   /* If this is a combined parallel+workshare region, this is a list
 446      of additional arguments needed by the combined parallel+workshare
 447      library call.  */
 448   tree ws_args;
 449
 450   /* The code for the omp directive of this region.  */
 451   enum gimple_code type;
 452
 453   /* Schedule kind, only used for OMP_FOR type regions.  */
 454   enum omp_clause_schedule_kind sched_kind;
 455
 456   /* True if this is a combined parallel+workshare region.  */
 457   bool is_combined_parallel;
 458 };
 459
 460 extern struct omp_region *root_omp_region;
 461 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 462                                           struct omp_region *);
 463 extern void free_omp_regions (void);
 464 void omp_expand_local (basic_block);
 465 extern tree find_omp_clause (tree, enum omp_clause_code);
 466 tree copy_var_decl (tree, tree, tree);
 467
 468 /*---------------------------------------------------------------------------
 469                               Function prototypes
 470 ---------------------------------------------------------------------------*/
 471 /* In tree-cfg.c  */
 472
 473 /* Location to track pending stmt for edge insertion.  */
 474 #define PENDING_STMT(e) ((e)->insns.g)
 475
 476 extern void delete_tree_cfg_annotations (void);
 477 extern bool stmt_ends_bb_p (gimple);
 478 extern bool is_ctrl_stmt (gimple);
 479 extern bool is_ctrl_altering_stmt (gimple);
 480 extern bool simple_goto_p (gimple);
 481 extern bool stmt_can_make_abnormal_goto (gimple);
 482 extern basic_block single_noncomplex_succ (basic_block bb);
 483 extern void gimple_dump_bb (basic_block, FILE *, int, int);
 484 extern void gimple_debug_bb (basic_block);
 485 extern basic_block gimple_debug_bb_n (int);
 486 extern void gimple_dump_cfg (FILE *, int);
 487 extern void gimple_debug_cfg (int);
 488 extern void dump_cfg_stats (FILE *);
 489 extern void dot_cfg (void);
 490 extern void debug_cfg_stats (void);
 491 extern void debug_loops (int);
 492 extern void debug_loop (struct loop *, int);
 493 extern void debug_loop_num (unsigned, int);
 494 extern void print_loops (FILE *, int);
 495 extern void print_loops_bb (FILE *, basic_block, int, int);
 496 extern void cleanup_dead_labels (void);
 497 extern void group_case_labels (void);
 498 extern gimple first_stmt (basic_block);
 499 extern gimple last_stmt (basic_block);
 500 extern gimple last_and_only_stmt (basic_block);
 501 extern edge find_taken_edge (basic_block, tree);
 502 extern basic_block label_to_block_fn (struct function *, tree);
 503 #define label_to_block(t) (label_to_block_fn (cfun, t))
 504 extern void notice_special_calls (gimple);
 505 extern void clear_special_calls (void);
 506 extern void verify_stmts (void);
 507 extern void verify_gimple (void);
 508 extern void verify_types_in_gimple_seq (gimple_seq);
 509 extern tree gimple_block_label (basic_block);
 510 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 511 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 512                                         basic_block *);
 513 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 514                                       basic_block *);
 515 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 516                                           VEC(basic_block,heap) **bbs_p);
 517 extern void add_phi_args_after_copy_bb (basic_block);
 518 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 519 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 520 extern bool gimple_purge_dead_eh_edges (basic_block);
 521 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 522 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 523                              tree, tree);
 524 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 525                              tree, tree, tree);
 526 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 527                              tree, tree, tree, tree);
 528 extern void init_empty_tree_cfg (void);
 529 extern void init_empty_tree_cfg_for_function (struct function *);
 530 extern void fold_cond_expr_cond (void);
 531 extern void make_abnormal_goto_edges (basic_block, bool);
 532 extern void replace_uses_by (tree, tree);
 533 extern void start_recording_case_labels (void);
 534 extern void end_recording_case_labels (void);
 535 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 536                                            basic_block, tree);
 537 void remove_edge_and_dominated_blocks (edge);
 538 void mark_virtual_ops_in_bb (basic_block);
 539
 540 /* In tree-cfgcleanup.c  */
 541 extern bitmap cfgcleanup_altered_bbs;
 542 extern bool cleanup_tree_cfg (void);
 543
 544 /* In tree-pretty-print.c.  */
 545 extern void dump_generic_bb (FILE *, basic_block, int, int);
 546 extern int op_code_prio (enum tree_code);
 547 extern int op_prio (const_tree);
 548 extern const char *op_symbol_code (enum tree_code);
 549
 550 /* In tree-dfa.c  */
 551 extern var_ann_t create_var_ann (tree);
 552 extern void renumber_gimple_stmt_uids (void);
 553 extern tree_ann_common_t create_tree_common_ann (tree);
 554 extern void dump_dfa_stats (FILE *);
 555 extern void debug_dfa_stats (void);
 556 extern void debug_referenced_vars (void);
 557 extern void dump_referenced_vars (FILE *);
 558 extern void dump_variable (FILE *, tree);
 559 extern void debug_variable (tree);
 560 extern tree get_virtual_var (tree);
 561 extern bool add_referenced_var (tree);
 562 extern void remove_referenced_var (tree);
 563 extern void mark_symbols_for_renaming (gimple);
 564 extern void find_new_referenced_vars (gimple);
 565 extern tree make_rename_temp (tree, const char *);
 566 extern void set_default_def (tree, tree);
 567 extern tree gimple_default_def (struct function *, tree);
 568 extern bool stmt_references_abnormal_ssa_name (gimple);
 569 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
 570                                      HOST_WIDE_INT *, HOST_WIDE_INT *);
 571 extern void find_referenced_vars_in (gimple);
 572
 573 /* In tree-phinodes.c  */
 574 extern void reserve_phi_args_for_new_edge (basic_block);
 575 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 576 extern gimple make_phi_node (tree var, int len);
 577 extern gimple create_phi_node (tree, basic_block);
 578 extern void add_phi_arg (gimple, tree, edge);
 579 extern void remove_phi_args (edge);
 580 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 581 extern void remove_phi_nodes (basic_block);
 582 extern void init_phinodes (void);
 583 extern void fini_phinodes (void);
 584 extern void release_phi_node (gimple);
 585 #ifdef GATHER_STATISTICS
 586 extern void phinodes_print_statistics (void);
 587 #endif
 588
 589 /* In gimple-low.c  */
 590 extern void record_vars_into (tree, tree);
 591 extern void record_vars (tree);
 592 extern bool block_may_fallthru (const_tree);
 593 extern bool gimple_seq_may_fallthru (gimple_seq);
 594 extern bool gimple_stmt_may_fallthru (gimple);
 595
 596
 597 /* In tree-ssa.c  */
 598
 599 /* Mapping for redirected edges.  */
 600 struct GTY(()) _edge_var_map {
 601   tree result;                  /* PHI result.  */
 602   tree def;                     /* PHI arg definition.  */
 603 };
 604 typedef struct _edge_var_map edge_var_map;
 605
 606 DEF_VEC_O(edge_var_map);
 607 DEF_VEC_ALLOC_O(edge_var_map, heap);
 608
 609 /* A vector of var maps.  */
 610 typedef VEC(edge_var_map, heap) *edge_var_map_vector;
 611
 612 extern void init_tree_ssa (struct function *);
 613 extern void redirect_edge_var_map_add (edge, tree, tree);
 614 extern void redirect_edge_var_map_clear (edge);
 615 extern void redirect_edge_var_map_dup (edge, edge);
 616 extern edge_var_map_vector redirect_edge_var_map_vector (edge);
 617 extern void redirect_edge_var_map_destroy (void);
 618
 619 extern edge ssa_redirect_edge (edge, basic_block);
 620 extern void flush_pending_stmts (edge);
 621 extern void verify_ssa (bool);
 622 extern void delete_tree_ssa (void);
 623 extern bool ssa_undefined_value_p (tree);
 624 extern void execute_update_addresses_taken (bool);
 625
 626 /* Call-back function for walk_use_def_chains().  At each reaching
 627    definition, a function with this prototype is called.  */
 628 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *);
 629
 630 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 631
 632
 633 /* In tree-into-ssa.c  */
 634 void update_ssa (unsigned);
 635 void delete_update_ssa (void);
 636 void register_new_name_mapping (tree, tree);
 637 tree create_new_def_for (tree, gimple, def_operand_p);
 638 bool need_ssa_update_p (struct function *);
 639 bool name_mappings_registered_p (void);
 640 bool name_registered_for_update_p (tree);
 641 bitmap ssa_names_to_replace (void);
 642 void release_ssa_name_after_update_ssa (tree);
 643 void compute_global_livein (bitmap, bitmap);
 644 void mark_sym_for_renaming (tree);
 645 void mark_set_for_renaming (bitmap);
 646 tree get_current_def (tree);
 647 void set_current_def (tree, tree);
 648
 649 /* In tree-ssanames.c  */
 650 extern void init_ssanames (struct function *, int);
 651 extern void fini_ssanames (void);
 652 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 653 extern tree duplicate_ssa_name (tree, gimple);
 654 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 655 extern void release_ssa_name (tree);
 656 extern void release_defs (gimple);
 657 extern void replace_ssa_name_symbol (tree, tree);
 658
 659 #ifdef GATHER_STATISTICS
 660 extern void ssanames_print_statistics (void);
 661 #endif
 662
 663 /* In tree-ssa-ccp.c  */
 664 bool fold_stmt (gimple_stmt_iterator *);
 665 bool fold_stmt_inplace (gimple);
 666 tree get_symbol_constant_value (tree);
 667 tree fold_const_aggregate_ref (tree);
 668 bool may_propagate_address_into_dereference (tree, tree);
 669
 670
 671 /* In tree-vrp.c  */
 672 tree vrp_evaluate_conditional (enum tree_code, tree, tree, gimple);
 673 bool simplify_stmt_using_ranges (gimple_stmt_iterator *);
 674
 675 /* In tree-ssa-dom.c  */
 676 extern void dump_dominator_optimization_stats (FILE *);
 677 extern void debug_dominator_optimization_stats (void);
 678 int loop_depth_of_name (tree);
 679 tree degenerate_phi_result (gimple);
 680
 681 /* In tree-ssa-copy.c  */
 682 extern void propagate_value (use_operand_p, tree);
 683 extern void propagate_tree_value (tree *, tree);
 684 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 685 extern void replace_exp (use_operand_p, tree);
 686 extern bool may_propagate_copy (tree, tree);
 687 extern bool may_propagate_copy_into_stmt (gimple, tree);
 688 extern bool may_propagate_copy_into_asm (tree);
 689
 690 /* Affine iv.  */
 691
 692 typedef struct
 693 {
 694   /* Iv = BASE + STEP * i.  */
 695   tree base, step;
 696
 697   /* True if this iv does not overflow.  */
 698   bool no_overflow;
 699 } affine_iv;
 700
 701 /* Description of number of iterations of a loop.  All the expressions inside
 702    the structure can be evaluated at the end of the loop's preheader
 703    (and due to ssa form, also anywhere inside the body of the loop).  */
 704
 705 struct tree_niter_desc
 706 {
 707   tree assumptions;     /* The boolean expression.  If this expression evaluates
 708                            to false, then the other fields in this structure
 709                            should not be used; there is no guarantee that they
 710                            will be correct.  */
 711   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 712                            the loop will exit in the first iteration (i.e.
 713                            its latch will not be executed), even if the niter
 714                            field says otherwise.  */
 715   tree niter;           /* The expression giving the number of iterations of
 716                            a loop (provided that assumptions == true and
 717                            may_be_zero == false), more precisely the number
 718                            of executions of the latch of the loop.  */
 719   double_int max;       /* The upper bound on the number of iterations of
 720                            the loop.  */
 721
 722   /* The simplified shape of the exit condition.  The loop exits if
 723      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 724      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 725      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 726      by loop unrolling.  */
 727   affine_iv control;
 728   tree bound;
 729   enum tree_code cmp;
 730 };
 731
 732 /* In tree-vectorizer.c */
 733 unsigned vectorize_loops (void);
 734 extern bool vect_can_force_dr_alignment_p (const_tree, unsigned int);
 735 extern tree get_vectype_for_scalar_type (tree);
 736
 737 /* In tree-ssa-phiopt.c */
 738 bool empty_block_p (basic_block);
 739 basic_block *blocks_in_phiopt_order (void);
 740
 741 /* In tree-ssa-loop*.c  */
 742
 743 void tree_ssa_lim (void);
 744 unsigned int tree_ssa_unswitch_loops (void);
 745 unsigned int canonicalize_induction_variables (void);
 746 unsigned int tree_unroll_loops_completely (bool, bool);
 747 unsigned int tree_ssa_prefetch_arrays (void);
 748 unsigned int remove_empty_loops (void);
 749 void tree_ssa_iv_optimize (void);
 750 unsigned tree_predictive_commoning (void);
 751 tree canonicalize_loop_ivs (struct loop *, htab_t, tree *);
 752 bool parallelize_loops (void);
 753
 754 bool loop_only_exit_p (const struct loop *, const_edge);
 755 bool number_of_iterations_exit (struct loop *, edge,
 756                                 struct tree_niter_desc *niter, bool);
 757 tree find_loop_niter (struct loop *, edge *);
 758 tree loop_niter_by_eval (struct loop *, edge);
 759 tree find_loop_niter_by_eval (struct loop *, edge *);
 760 void estimate_numbers_of_iterations (void);
 761 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 762 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 763
 764 bool nowrap_type_p (tree);
 765 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 766 enum ev_direction scev_direction (const_tree);
 767
 768 void free_numbers_of_iterations_estimates (void);
 769 void free_numbers_of_iterations_estimates_loop (struct loop *);
 770 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 771 void verify_loop_closed_ssa (void);
 772 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 773 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 774                 tree *, tree *);
 775 basic_block split_loop_exit_edge (edge);
 776 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 777                                      bool *);
 778 basic_block ip_end_pos (struct loop *);
 779 basic_block ip_normal_pos (struct loop *);
 780 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 781                                          unsigned int, sbitmap,
 782                                          edge, VEC (edge, heap) **,
 783                                          int);
 784 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 785 void rename_variables_in_loop (struct loop *);
 786 void rename_variables_in_bb (basic_block bb);
 787 struct loop *tree_ssa_loop_version (struct loop *, tree,
 788                                     basic_block *);
 789 tree expand_simple_operations (tree);
 790 void substitute_in_loop_info (struct loop *, tree, tree);
 791 edge single_dom_exit (struct loop *);
 792 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 793                         struct tree_niter_desc *niter);
 794 void tree_unroll_loop (struct loop *, unsigned,
 795                        edge, struct tree_niter_desc *);
 796 typedef void (*transform_callback)(struct loop *, void *);
 797 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 798                                      edge, struct tree_niter_desc *,
 799                                      transform_callback, void *);
 800 bool contains_abnormal_ssa_name_p (tree);
 801 bool stmt_dominates_stmt_p (gimple, gimple);
 802 void mark_virtual_ops_for_renaming (gimple);
 803
 804 /* In tree-ssa-threadedge.c */
 805 extern void threadedge_initialize_values (void);
 806 extern void threadedge_finalize_values (void);
 807 extern VEC(tree,heap) *ssa_name_values;
 808 #define SSA_NAME_VALUE(x) \
 809     (SSA_NAME_VERSION(x) < VEC_length(tree, ssa_name_values) \
 810      ? VEC_index(tree, ssa_name_values, SSA_NAME_VERSION(x)) \
 811      : NULL_TREE)
 812 extern void set_ssa_name_value (tree, tree);
 813 extern bool potentially_threadable_block (basic_block);
 814 extern void thread_across_edge (gimple, edge, bool,
 815                                 VEC(tree, heap) **, tree (*) (gimple, gimple));
 816
 817 /* In tree-ssa-loop-im.c  */
 818 /* The possibilities of statement movement.  */
 819
 820 enum move_pos
 821   {
 822     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 823     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 824                                    become executed -- memory accesses, ... */
 825     MOVE_POSSIBLE               /* Unlimited movement.  */
 826   };
 827 extern enum move_pos movement_possibility (gimple);
 828 char *get_lsm_tmp_name (tree, unsigned);
 829
 830 /* In tree-flow-inline.h  */
 831 static inline bool is_call_clobbered (const_tree);
 832 static inline void set_is_used (tree);
 833 static inline bool unmodifiable_var_p (const_tree);
 834 static inline bool ref_contains_array_ref (const_tree);
 835 static inline bool array_ref_contains_indirect_ref (const_tree);
 836
 837 /* In tree-eh.c  */
 838 extern void make_eh_edges (gimple);
 839 extern bool tree_could_trap_p (tree);
 840 extern bool operation_could_trap_helper_p (enum tree_code, bool, bool, bool,
 841                                            bool, tree, bool *);
 842 extern bool operation_could_trap_p (enum tree_code, bool, bool, tree);
 843 extern bool stmt_could_throw_p (gimple);
 844 extern bool tree_could_throw_p (tree);
 845 extern bool stmt_can_throw_internal (gimple);
 846 extern bool stmt_can_throw_external (gimple);
 847 extern void add_stmt_to_eh_region (gimple, int);
 848 extern bool remove_stmt_from_eh_region (gimple);
 849 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 850 extern void add_stmt_to_eh_region_fn (struct function *, gimple, int);
 851 extern bool remove_stmt_from_eh_region_fn (struct function *, gimple);
 852 extern int lookup_stmt_eh_region_fn (struct function *, gimple);
 853 extern int lookup_expr_eh_region (tree);
 854 extern int lookup_stmt_eh_region (gimple);
 855 extern bool verify_eh_edges (gimple);
 856
 857
 858 /* In tree-ssa-pre.c  */
 859 struct pre_expr_d;
 860 void add_to_value (unsigned int, struct pre_expr_d *);
 861 void debug_value_expressions (unsigned int);
 862 void print_value_expressions (FILE *, unsigned int);
 863
 864 /* In tree-ssa-sink.c  */
 865 bool is_hidden_global_store (gimple);
 866
 867 /* In tree-loop-linear.c  */
 868 extern void linear_transform_loops (void);
 869 extern unsigned perfect_loop_nest_depth (struct loop *);
 870
 871 /* In graphite.c  */
 872 extern void graphite_transform_loops (void);
 873
 874 /* In tree-data-ref.c  */
 875 extern void tree_check_data_deps (void);
 876
 877 /* In tree-ssa-loop-ivopts.c  */
 878 bool expr_invariant_in_loop_p (struct loop *, tree);
 879 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 880 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode);
 881 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode, bool);
 882
 883 /* In tree-ssa-threadupdate.c.  */
 884 extern bool thread_through_all_blocks (bool);
 885 extern void register_jump_thread (edge, edge);
 886
 887 /* In gimplify.c  */
 888 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 889 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 890                                bool, enum gsi_iterator_update);
 891 tree gimple_fold_indirect_ref (tree);
 892 void mark_addressable (tree);
 893
 894 /* In tree-ssa-live.c */
 895 extern void remove_unused_locals (void);
 896 extern void dump_scope_blocks (FILE *, int);
 897 extern void debug_scope_blocks (int);
 898
 899 /* In tree-ssa-address.c  */
 900
 901 /* Description of a memory address.  */
 902
 903 struct mem_address
 904 {
 905   tree symbol, base, index, step, offset;
 906 };
 907
 908 struct affine_tree_combination;
 909 tree create_mem_ref (gimple_stmt_iterator *, tree,
 910                      struct affine_tree_combination *, bool);
 911 rtx addr_for_mem_ref (struct mem_address *, bool);
 912 void get_address_description (tree, struct mem_address *);
 913 tree maybe_fold_tmr (tree);
 914
 915 unsigned int execute_free_datastructures (void);
 916 unsigned int execute_fixup_cfg (void);
 917
 918 #include "tree-flow-inline.h"
 919
 920 void swap_tree_operands (gimple, tree *, tree *);
 921
 922 int least_common_multiple (int, int);
 923 edge redirect_eh_edge (edge e, basic_block new_bb);
 924
 925 #endif /* _TREE_FLOW_H  */