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   /* A map of decls to artificial ssa-names that point to the partition
  67      of the decl.  */
  68   struct pointer_map_t * GTY((skip(""))) decls_to_pointers;
  69
  70   /* Free list of SSA_NAMEs.  */
  71   tree free_ssanames;
  72
  73   /* Hashtable holding definition for symbol.  If this field is not NULL, it
  74      means that the first reference to this variable in the function is a
  75      USE or a VUSE.  In those cases, the SSA renamer creates an SSA name
  76      for this variable with an empty defining statement.  */
  77   htab_t GTY((param_is (union tree_node))) default_defs;
  78
  79   /* Symbols whose SSA form needs to be updated or created for the first
  80      time.  */
  81   bitmap syms_to_rename;
  82
  83   /* True if the code is in ssa form.  */
  84   unsigned int in_ssa_p : 1;
  85
  86   struct ssa_operands ssa_operands;
  87 };
  88
  89 /* Accessors for internal use only.  Generic code should use abstraction
  90    provided by tree-flow-inline.h or specific modules.  */
  91 #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames
  92 #define SSANAMES(fun) (fun)->gimple_df->ssa_names
  93 #define MODIFIED_NORETURN_CALLS(fun) (fun)->gimple_df->modified_noreturn_calls
  94 #define DEFAULT_DEFS(fun) (fun)->gimple_df->default_defs
  95 #define SYMS_TO_RENAME(fun) (fun)->gimple_df->syms_to_rename
  96
  97 typedef struct
  98 {
  99   htab_t htab;
 100   PTR *slot;
 101   PTR *limit;
 102 } htab_iterator;
 103
 104 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
 105    storing each element in RESULT, which is of type TYPE.  */
 106 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
 107   for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
 108         !end_htab_p (&(ITER)); \
 109         RESULT = (TYPE) next_htab_element (&(ITER)))
 110
 111 /*---------------------------------------------------------------------------
 112                       Attributes for SSA_NAMEs.
 113
 114   NOTE: These structures are stored in struct tree_ssa_name
 115   but are only used by the tree optimizers, so it makes better sense
 116   to declare them here to avoid recompiling unrelated files when
 117   making changes.
 118 ---------------------------------------------------------------------------*/
 119
 120 /* Aliasing information for SSA_NAMEs representing pointer variables.  */
 121 struct GTY(()) ptr_info_def
 122 {
 123   /* The points-to solution, TBAA-pruned if the pointer is dereferenced.  */
 124   struct pt_solution pt;
 125 };
 126
 127
 128 /*---------------------------------------------------------------------------
 129                    Tree annotations stored in tree_base.ann
 130 ---------------------------------------------------------------------------*/
 131 enum tree_ann_type { TREE_ANN_COMMON, VAR_ANN, FUNCTION_ANN };
 132
 133 struct GTY(()) tree_ann_common_d {
 134   /* Annotation type.  */
 135   enum tree_ann_type type;
 136
 137   /* Record EH landing pad number into a statement tree created
 138      during RTL expansion (see gimple_to_tree).  */
 139   int lp_nr;
 140
 141   /* Pointer to original GIMPLE statement.  Used during RTL expansion
 142      (see gimple_to_tree).  */
 143   gimple stmt;
 144 };
 145
 146 /* It is advantageous to avoid things like life analysis for variables which
 147    do not need PHI nodes.  This enum describes whether or not a particular
 148    variable may need a PHI node.  */
 149
 150 enum need_phi_state {
 151   /* This is the default.  If we are still in this state after finding
 152      all the definition and use sites, then we will assume the variable
 153      needs PHI nodes.  This is probably an overly conservative assumption.  */
 154   NEED_PHI_STATE_UNKNOWN,
 155
 156   /* This state indicates that we have seen one or more sets of the
 157      variable in a single basic block and that the sets dominate all
 158      uses seen so far.  If after finding all definition and use sites
 159      we are still in this state, then the variable does not need any
 160      PHI nodes.  */
 161   NEED_PHI_STATE_NO,
 162
 163   /* This state indicates that we have either seen multiple definitions of
 164      the variable in multiple blocks, or that we encountered a use in a
 165      block that was not dominated by the block containing the set(s) of
 166      this variable.  This variable is assumed to need PHI nodes.  */
 167   NEED_PHI_STATE_MAYBE
 168 };
 169
 170
 171 /* The "no alias" attribute allows alias analysis to make more
 172    aggressive assumptions when assigning alias sets, computing
 173    points-to information and memory partitions.  These attributes
 174    are the result of user annotations or flags (e.g.,
 175    -fargument-noalias).  */
 176 enum noalias_state {
 177     /* Default state.  No special assumptions can be made about this
 178        symbol.  */
 179     MAY_ALIAS = 0,
 180
 181     /* The symbol does not alias with other symbols that have a
 182        NO_ALIAS* attribute.  */
 183     NO_ALIAS,
 184
 185     /* The symbol does not alias with other symbols that have a
 186        NO_ALIAS*, and it may not alias with global symbols.  */
 187     NO_ALIAS_GLOBAL,
 188
 189     /* The symbol does not alias with any other symbols.  */
 190     NO_ALIAS_ANYTHING
 191 };
 192
 193
 194 struct GTY(()) var_ann_d {
 195   struct tree_ann_common_d common;
 196
 197   /* Used when building base variable structures in a var_map.  */
 198   unsigned base_var_processed : 1;
 199
 200   /* Nonzero if this variable was used after SSA optimizations were
 201      applied.  We set this when translating out of SSA form.  */
 202   unsigned used : 1;
 203
 204   /* This field indicates whether or not the variable may need PHI nodes.
 205      See the enum's definition for more detailed information about the
 206      states.  */
 207   ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
 208
 209   /* True for HEAP artificial variables.  These variables represent
 210      the memory area allocated by a call to malloc.  */
 211   unsigned is_heapvar : 1;
 212
 213   /* This field describes several "no alias" attributes that some
 214      symbols are known to have.  See the enum's definition for more
 215      information on each attribute.  */
 216   ENUM_BITFIELD (noalias_state) noalias_state : 2;
 217
 218   /* Used by var_map for the base index of ssa base variables.  */
 219   unsigned base_index;
 220
 221   /* During into-ssa and the dominator optimizer, this field holds the
 222      current version of this variable (an SSA_NAME).  */
 223   tree current_def;
 224 };
 225
 226
 227 /* Immediate use lists are used to directly access all uses for an SSA
 228    name and get pointers to the statement for each use.
 229
 230    The structure ssa_use_operand_d consists of PREV and NEXT pointers
 231    to maintain the list.  A USE pointer, which points to address where
 232    the use is located and a LOC pointer which can point to the
 233    statement where the use is located, or, in the case of the root
 234    node, it points to the SSA name itself.
 235
 236    The list is anchored by an occurrence of ssa_operand_d *in* the
 237    ssa_name node itself (named 'imm_uses').  This node is uniquely
 238    identified by having a NULL USE pointer. and the LOC pointer
 239    pointing back to the ssa_name node itself.  This node forms the
 240    base for a circular list, and initially this is the only node in
 241    the list.
 242
 243    Fast iteration allows each use to be examined, but does not allow
 244    any modifications to the uses or stmts.
 245
 246    Normal iteration allows insertion, deletion, and modification. the
 247    iterator manages this by inserting a marker node into the list
 248    immediately before the node currently being examined in the list.
 249    this marker node is uniquely identified by having null stmt *and* a
 250    null use pointer.
 251
 252    When iterating to the next use, the iteration routines check to see
 253    if the node after the marker has changed. if it has, then the node
 254    following the marker is now the next one to be visited. if not, the
 255    marker node is moved past that node in the list (visualize it as
 256    bumping the marker node through the list).  this continues until
 257    the marker node is moved to the original anchor position. the
 258    marker node is then removed from the list.
 259
 260    If iteration is halted early, the marker node must be removed from
 261    the list before continuing.  */
 262 typedef struct immediate_use_iterator_d
 263 {
 264   /* This is the current use the iterator is processing.  */
 265   ssa_use_operand_t *imm_use;
 266   /* This marks the last use in the list (use node from SSA_NAME)  */
 267   ssa_use_operand_t *end_p;
 268   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 269   ssa_use_operand_t iter_node;
 270   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 271      the next one is traversed to, so it must be cached early.  */
 272   ssa_use_operand_t *next_imm_name;
 273 } imm_use_iterator;
 274
 275
 276 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 277    modifying stmts will cause this iterator to malfunction.  */
 278
 279 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)                       \
 280   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 281        !end_readonly_imm_use_p (&(ITER));                       \
 282        (DEST) = next_readonly_imm_use (&(ITER)))
 283
 284 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 285
 286 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 287   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 288        !end_imm_use_stmt_p (&(ITER));                           \
 289        (STMT) = next_imm_use_stmt (&(ITER)))
 290
 291 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 292    do so will result in leaving a iterator marker node in the immediate
 293    use list, and nothing good will come from that.   */
 294 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 295    {                                                            \
 296      end_imm_use_stmt_traverse (&(ITER));                       \
 297      break;                                                     \
 298    }
 299
 300
 301 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 302    get access to each occurrence of ssavar on the stmt returned by
 303    that iterator..  for instance:
 304
 305      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 306        {
 307          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 308            {
 309              SET_USE (use_p, blah);
 310            }
 311          update_stmt (stmt);
 312        }                                                         */
 313
 314 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 315   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 316        !end_imm_use_on_stmt_p (&(ITER));                        \
 317        (DEST) = next_imm_use_on_stmt (&(ITER)))
 318
 319
 320
 321 union GTY((desc ("ann_type ((tree_ann_t)&%h)"))) tree_ann_d {
 322   struct tree_ann_common_d GTY((tag ("TREE_ANN_COMMON"))) common;
 323   struct var_ann_d GTY((tag ("VAR_ANN"))) vdecl;
 324 };
 325
 326 typedef union tree_ann_d *tree_ann_t;
 327 typedef struct var_ann_d *var_ann_t;
 328 typedef struct tree_ann_common_d *tree_ann_common_t;
 329
 330 static inline tree_ann_common_t tree_common_ann (const_tree);
 331 static inline tree_ann_common_t get_tree_common_ann (tree);
 332 static inline var_ann_t var_ann (const_tree);
 333 static inline var_ann_t get_var_ann (tree);
 334 static inline enum tree_ann_type ann_type (tree_ann_t);
 335 static inline void update_stmt (gimple);
 336 static inline int get_lineno (const_gimple);
 337
 338 /*---------------------------------------------------------------------------
 339                   Structure representing predictions in tree level.
 340 ---------------------------------------------------------------------------*/
 341 struct GTY((chain_next ("%h.ep_next"))) edge_prediction {
 342   struct edge_prediction *ep_next;
 343   edge ep_edge;
 344   enum br_predictor ep_predictor;
 345   int ep_probability;
 346 };
 347
 348 /* Accessors for basic block annotations.  */
 349 static inline gimple_seq phi_nodes (const_basic_block);
 350 static inline void set_phi_nodes (basic_block, gimple_seq);
 351
 352 /*---------------------------------------------------------------------------
 353                               Global declarations
 354 ---------------------------------------------------------------------------*/
 355 struct GTY(()) int_tree_map {
 356
 357   unsigned int uid;
 358   tree to;
 359 };
 360
 361 extern unsigned int int_tree_map_hash (const void *);
 362 extern int int_tree_map_eq (const void *, const void *);
 363
 364 extern unsigned int uid_decl_map_hash (const void *);
 365 extern int uid_decl_map_eq (const void *, const void *);
 366
 367 typedef struct
 368 {
 369   htab_iterator hti;
 370 } referenced_var_iterator;
 371
 372
 373 /* This macro loops over all the referenced vars, one at a time, putting the
 374    current var in VAR.  Note:  You are not allowed to add referenced variables
 375    to the hashtable while using this macro.  Doing so may cause it to behave
 376    erratically.  */
 377
 378 #define FOR_EACH_REFERENCED_VAR(VAR, ITER) \
 379   for ((VAR) = first_referenced_var (&(ITER)); \
 380        !end_referenced_vars_p (&(ITER)); \
 381        (VAR) = next_referenced_var (&(ITER)))
 382
 383
 384 typedef struct
 385 {
 386   int i;
 387 } safe_referenced_var_iterator;
 388
 389 /* This macro loops over all the referenced vars, one at a time, putting the
 390    current var in VAR.  You are allowed to add referenced variables during the
 391    execution of this macro, however, the macro will not iterate over them.  It
 392    requires a temporary vector of trees, VEC, whose lifetime is controlled by
 393    the caller.  The purpose of the vector is to temporarily store the
 394    referenced_variables hashtable so that adding referenced variables does not
 395    affect the hashtable.  */
 396
 397 #define FOR_EACH_REFERENCED_VAR_SAFE(VAR, VEC, ITER) \
 398   for ((ITER).i = 0, fill_referenced_var_vec (&(VEC)); \
 399        VEC_iterate (tree, (VEC), (ITER).i, (VAR)); \
 400        (ITER).i++)
 401
 402 extern tree referenced_var_lookup (unsigned int);
 403 extern bool referenced_var_check_and_insert (tree);
 404 #define num_referenced_vars htab_elements (gimple_referenced_vars (cfun))
 405 #define referenced_var(i) referenced_var_lookup (i)
 406
 407 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
 408 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
 409
 410 /* Macros for showing usage statistics.  */
 411 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 412                   ? (x)                                 \
 413                   : ((x) < 1024*1024*10                 \
 414                      ? (x) / 1024                       \
 415                      : (x) / (1024*1024))))
 416
 417 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 418
 419 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 420
 421 /*---------------------------------------------------------------------------
 422                               OpenMP Region Tree
 423 ---------------------------------------------------------------------------*/
 424
 425 /* Parallel region information.  Every parallel and workshare
 426    directive is enclosed between two markers, the OMP_* directive
 427    and a corresponding OMP_RETURN statement.  */
 428
 429 struct omp_region
 430 {
 431   /* The enclosing region.  */
 432   struct omp_region *outer;
 433
 434   /* First child region.  */
 435   struct omp_region *inner;
 436
 437   /* Next peer region.  */
 438   struct omp_region *next;
 439
 440   /* Block containing the omp directive as its last stmt.  */
 441   basic_block entry;
 442
 443   /* Block containing the OMP_RETURN as its last stmt.  */
 444   basic_block exit;
 445
 446   /* Block containing the OMP_CONTINUE as its last stmt.  */
 447   basic_block cont;
 448
 449   /* If this is a combined parallel+workshare region, this is a list
 450      of additional arguments needed by the combined parallel+workshare
 451      library call.  */
 452   tree ws_args;
 453
 454   /* The code for the omp directive of this region.  */
 455   enum gimple_code type;
 456
 457   /* Schedule kind, only used for OMP_FOR type regions.  */
 458   enum omp_clause_schedule_kind sched_kind;
 459
 460   /* True if this is a combined parallel+workshare region.  */
 461   bool is_combined_parallel;
 462 };
 463
 464 extern struct omp_region *root_omp_region;
 465 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 466                                           struct omp_region *);
 467 extern void free_omp_regions (void);
 468 void omp_expand_local (basic_block);
 469 extern tree find_omp_clause (tree, enum omp_clause_code);
 470 tree copy_var_decl (tree, tree, tree);
 471
 472 /*---------------------------------------------------------------------------
 473                               Function prototypes
 474 ---------------------------------------------------------------------------*/
 475 /* In tree-cfg.c  */
 476
 477 /* Location to track pending stmt for edge insertion.  */
 478 #define PENDING_STMT(e) ((e)->insns.g)
 479
 480 extern void delete_tree_cfg_annotations (void);
 481 extern bool stmt_ends_bb_p (gimple);
 482 extern bool is_ctrl_stmt (gimple);
 483 extern bool is_ctrl_altering_stmt (gimple);
 484 extern bool simple_goto_p (gimple);
 485 extern bool stmt_can_make_abnormal_goto (gimple);
 486 extern basic_block single_noncomplex_succ (basic_block bb);
 487 extern void gimple_dump_bb (basic_block, FILE *, int, int);
 488 extern void gimple_debug_bb (basic_block);
 489 extern basic_block gimple_debug_bb_n (int);
 490 extern void gimple_dump_cfg (FILE *, int);
 491 extern void gimple_debug_cfg (int);
 492 extern void dump_cfg_stats (FILE *);
 493 extern void dot_cfg (void);
 494 extern void debug_cfg_stats (void);
 495 extern void debug_loops (int);
 496 extern void debug_loop (struct loop *, int);
 497 extern void debug_loop_num (unsigned, int);
 498 extern void print_loops (FILE *, int);
 499 extern void print_loops_bb (FILE *, basic_block, int, int);
 500 extern void cleanup_dead_labels (void);
 501 extern void group_case_labels (void);
 502 extern gimple first_stmt (basic_block);
 503 extern gimple last_stmt (basic_block);
 504 extern gimple last_and_only_stmt (basic_block);
 505 extern edge find_taken_edge (basic_block, tree);
 506 extern basic_block label_to_block_fn (struct function *, tree);
 507 #define label_to_block(t) (label_to_block_fn (cfun, t))
 508 extern void notice_special_calls (gimple);
 509 extern void clear_special_calls (void);
 510 extern void verify_stmts (void);
 511 extern void verify_gimple (void);
 512 extern void verify_types_in_gimple_seq (gimple_seq);
 513 extern tree gimple_block_label (basic_block);
 514 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 515 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 516                                         basic_block *);
 517 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 518                                       basic_block *);
 519 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 520                                           VEC(basic_block,heap) **bbs_p);
 521 extern void add_phi_args_after_copy_bb (basic_block);
 522 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 523 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 524 extern bool gimple_purge_dead_eh_edges (basic_block);
 525 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 526 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 527                              tree, tree);
 528 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 529                              tree, tree, tree);
 530 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 531                              tree, tree, tree, tree);
 532 extern void init_empty_tree_cfg (void);
 533 extern void init_empty_tree_cfg_for_function (struct function *);
 534 extern void fold_cond_expr_cond (void);
 535 extern void make_abnormal_goto_edges (basic_block, bool);
 536 extern void replace_uses_by (tree, tree);
 537 extern void start_recording_case_labels (void);
 538 extern void end_recording_case_labels (void);
 539 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 540                                            basic_block, tree);
 541 void remove_edge_and_dominated_blocks (edge);
 542 void mark_virtual_ops_in_bb (basic_block);
 543 bool tree_node_can_be_shared (tree);
 544
 545 /* In tree-cfgcleanup.c  */
 546 extern bitmap cfgcleanup_altered_bbs;
 547 extern bool cleanup_tree_cfg (void);
 548
 549 /* In tree-pretty-print.c.  */
 550 extern void dump_generic_bb (FILE *, basic_block, int, int);
 551 extern int op_code_prio (enum tree_code);
 552 extern int op_prio (const_tree);
 553 extern const char *op_symbol_code (enum tree_code);
 554
 555 /* In tree-dfa.c  */
 556 extern var_ann_t create_var_ann (tree);
 557 extern void renumber_gimple_stmt_uids (void);
 558 extern void renumber_gimple_stmt_uids_in_blocks (basic_block *, int);
 559 extern tree_ann_common_t create_tree_common_ann (tree);
 560 extern void dump_dfa_stats (FILE *);
 561 extern void debug_dfa_stats (void);
 562 extern void debug_referenced_vars (void);
 563 extern void dump_referenced_vars (FILE *);
 564 extern void dump_variable (FILE *, tree);
 565 extern void debug_variable (tree);
 566 extern tree get_virtual_var (tree);
 567 extern bool add_referenced_var (tree);
 568 extern void remove_referenced_var (tree);
 569 extern void mark_symbols_for_renaming (gimple);
 570 extern void find_new_referenced_vars (gimple);
 571 extern tree make_rename_temp (tree, const char *);
 572 extern void set_default_def (tree, tree);
 573 extern tree gimple_default_def (struct function *, tree);
 574 extern bool stmt_references_abnormal_ssa_name (gimple);
 575 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
 576                                      HOST_WIDE_INT *, HOST_WIDE_INT *);
 577 extern void find_referenced_vars_in (gimple);
 578
 579 /* In tree-phinodes.c  */
 580 extern void reserve_phi_args_for_new_edge (basic_block);
 581 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 582 extern gimple make_phi_node (tree var, int len);
 583 extern gimple create_phi_node (tree, basic_block);
 584 extern void add_phi_arg (gimple, tree, edge, source_location);
 585 extern void remove_phi_args (edge);
 586 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 587 extern void remove_phi_nodes (basic_block);
 588 extern void init_phinodes (void);
 589 extern void fini_phinodes (void);
 590 extern void release_phi_node (gimple);
 591 #ifdef GATHER_STATISTICS
 592 extern void phinodes_print_statistics (void);
 593 #endif
 594
 595 /* In gimple-low.c  */
 596 extern void record_vars_into (tree, tree);
 597 extern void record_vars (tree);
 598 extern bool block_may_fallthru (const_tree);
 599 extern bool gimple_seq_may_fallthru (gimple_seq);
 600 extern bool gimple_stmt_may_fallthru (gimple);
 601 extern bool gimple_check_call_args (gimple);
 602
 603
 604 /* In tree-ssa.c  */
 605
 606 /* Mapping for redirected edges.  */
 607 struct GTY(()) _edge_var_map {
 608   tree result;                  /* PHI result.  */
 609   tree def;                     /* PHI arg definition.  */
 610   source_location locus;        /* PHI arg location.  */
 611 };
 612 typedef struct _edge_var_map edge_var_map;
 613
 614 DEF_VEC_O(edge_var_map);
 615 DEF_VEC_ALLOC_O(edge_var_map, heap);
 616
 617 /* A vector of var maps.  */
 618 typedef VEC(edge_var_map, heap) *edge_var_map_vector;
 619
 620 extern void init_tree_ssa (struct function *);
 621 extern void redirect_edge_var_map_add (edge, tree, tree, source_location);
 622 extern void redirect_edge_var_map_clear (edge);
 623 extern void redirect_edge_var_map_dup (edge, edge);
 624 extern edge_var_map_vector redirect_edge_var_map_vector (edge);
 625 extern void redirect_edge_var_map_destroy (void);
 626
 627 extern edge ssa_redirect_edge (edge, basic_block);
 628 extern void flush_pending_stmts (edge);
 629 extern void verify_ssa (bool);
 630 extern void delete_tree_ssa (void);
 631 extern bool ssa_undefined_value_p (tree);
 632 extern void execute_update_addresses_taken (bool);
 633
 634 /* Call-back function for walk_use_def_chains().  At each reaching
 635    definition, a function with this prototype is called.  */
 636 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *);
 637
 638 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 639
 640 void propagate_defs_into_debug_stmts (gimple, basic_block,
 641                                       const gimple_stmt_iterator *);
 642 void propagate_var_def_into_debug_stmts (tree, basic_block,
 643                                          const gimple_stmt_iterator *);
 644 void release_defs_bitset (bitmap toremove);
 645
 646 /* In tree-into-ssa.c  */
 647 void update_ssa (unsigned);
 648 void delete_update_ssa (void);
 649 void register_new_name_mapping (tree, tree);
 650 tree create_new_def_for (tree, gimple, def_operand_p);
 651 bool need_ssa_update_p (struct function *);
 652 bool name_mappings_registered_p (void);
 653 bool name_registered_for_update_p (tree);
 654 bitmap ssa_names_to_replace (void);
 655 void release_ssa_name_after_update_ssa (tree);
 656 void compute_global_livein (bitmap, bitmap);
 657 void mark_sym_for_renaming (tree);
 658 void mark_set_for_renaming (bitmap);
 659 tree get_current_def (tree);
 660 void set_current_def (tree, tree);
 661
 662 /* In tree-ssanames.c  */
 663 extern void init_ssanames (struct function *, int);
 664 extern void fini_ssanames (void);
 665 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 666 extern tree duplicate_ssa_name (tree, gimple);
 667 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 668 extern void release_ssa_name (tree);
 669 extern void release_defs (gimple);
 670 extern void replace_ssa_name_symbol (tree, tree);
 671
 672 #ifdef GATHER_STATISTICS
 673 extern void ssanames_print_statistics (void);
 674 #endif
 675
 676 /* In tree-ssa-ccp.c  */
 677 bool fold_stmt (gimple_stmt_iterator *);
 678 bool fold_stmt_inplace (gimple);
 679 tree get_symbol_constant_value (tree);
 680 tree fold_const_aggregate_ref (tree);
 681 bool may_propagate_address_into_dereference (tree, tree);
 682
 683
 684 /* In tree-ssa-dom.c  */
 685 extern void dump_dominator_optimization_stats (FILE *);
 686 extern void debug_dominator_optimization_stats (void);
 687 int loop_depth_of_name (tree);
 688 tree degenerate_phi_result (gimple);
 689
 690 /* In tree-ssa-copy.c  */
 691 extern void propagate_value (use_operand_p, tree);
 692 extern void propagate_tree_value (tree *, tree);
 693 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 694 extern void replace_exp (use_operand_p, tree);
 695 extern bool may_propagate_copy (tree, tree);
 696 extern bool may_propagate_copy_into_stmt (gimple, tree);
 697 extern bool may_propagate_copy_into_asm (tree);
 698
 699 /* Affine iv.  */
 700
 701 typedef struct
 702 {
 703   /* Iv = BASE + STEP * i.  */
 704   tree base, step;
 705
 706   /* True if this iv does not overflow.  */
 707   bool no_overflow;
 708 } affine_iv;
 709
 710 /* Description of number of iterations of a loop.  All the expressions inside
 711    the structure can be evaluated at the end of the loop's preheader
 712    (and due to ssa form, also anywhere inside the body of the loop).  */
 713
 714 struct tree_niter_desc
 715 {
 716   tree assumptions;     /* The boolean expression.  If this expression evaluates
 717                            to false, then the other fields in this structure
 718                            should not be used; there is no guarantee that they
 719                            will be correct.  */
 720   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 721                            the loop will exit in the first iteration (i.e.
 722                            its latch will not be executed), even if the niter
 723                            field says otherwise.  */
 724   tree niter;           /* The expression giving the number of iterations of
 725                            a loop (provided that assumptions == true and
 726                            may_be_zero == false), more precisely the number
 727                            of executions of the latch of the loop.  */
 728   double_int max;       /* The upper bound on the number of iterations of
 729                            the loop.  */
 730
 731   /* The simplified shape of the exit condition.  The loop exits if
 732      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 733      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 734      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 735      by loop unrolling.  */
 736   affine_iv control;
 737   tree bound;
 738   enum tree_code cmp;
 739 };
 740
 741 /* In tree-ssa-phiopt.c */
 742 bool empty_block_p (basic_block);
 743 basic_block *blocks_in_phiopt_order (void);
 744
 745 /* In tree-ssa-loop*.c  */
 746
 747 void tree_ssa_lim (void);
 748 unsigned int tree_ssa_unswitch_loops (void);
 749 unsigned int canonicalize_induction_variables (void);
 750 unsigned int tree_unroll_loops_completely (bool, bool);
 751 unsigned int tree_ssa_prefetch_arrays (void);
 752 void tree_ssa_iv_optimize (void);
 753 unsigned tree_predictive_commoning (void);
 754 tree canonicalize_loop_ivs (struct loop *, tree *);
 755 bool parallelize_loops (void);
 756
 757 bool loop_only_exit_p (const struct loop *, const_edge);
 758 bool number_of_iterations_exit (struct loop *, edge,
 759                                 struct tree_niter_desc *niter, bool);
 760 tree find_loop_niter (struct loop *, edge *);
 761 tree loop_niter_by_eval (struct loop *, edge);
 762 tree find_loop_niter_by_eval (struct loop *, edge *);
 763 void estimate_numbers_of_iterations (void);
 764 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 765 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 766
 767 bool nowrap_type_p (tree);
 768 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 769 enum ev_direction scev_direction (const_tree);
 770
 771 void free_numbers_of_iterations_estimates (void);
 772 void free_numbers_of_iterations_estimates_loop (struct loop *);
 773 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 774 void verify_loop_closed_ssa (void);
 775 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 776 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 777                 tree *, tree *);
 778 basic_block split_loop_exit_edge (edge);
 779 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 780                                      bool *);
 781 basic_block ip_end_pos (struct loop *);
 782 basic_block ip_normal_pos (struct loop *);
 783 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 784                                          unsigned int, sbitmap,
 785                                          edge, VEC (edge, heap) **,
 786                                          int);
 787 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 788 void rename_variables_in_loop (struct loop *);
 789 void rename_variables_in_bb (basic_block bb);
 790 struct loop *tree_ssa_loop_version (struct loop *, tree,
 791                                     basic_block *);
 792 tree expand_simple_operations (tree);
 793 void substitute_in_loop_info (struct loop *, tree, tree);
 794 edge single_dom_exit (struct loop *);
 795 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 796                         struct tree_niter_desc *niter);
 797 void tree_unroll_loop (struct loop *, unsigned,
 798                        edge, struct tree_niter_desc *);
 799 typedef void (*transform_callback)(struct loop *, void *);
 800 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 801                                      edge, struct tree_niter_desc *,
 802                                      transform_callback, void *);
 803 bool contains_abnormal_ssa_name_p (tree);
 804 bool stmt_dominates_stmt_p (gimple, gimple);
 805 void mark_virtual_ops_for_renaming (gimple);
 806
 807 /* In tree-ssa-dce.c */
 808 void mark_virtual_phi_result_for_renaming (gimple);
 809
 810 /* In tree-ssa-threadedge.c */
 811 extern void threadedge_initialize_values (void);
 812 extern void threadedge_finalize_values (void);
 813 extern VEC(tree,heap) *ssa_name_values;
 814 #define SSA_NAME_VALUE(x) \
 815     (SSA_NAME_VERSION(x) < VEC_length(tree, ssa_name_values) \
 816      ? VEC_index(tree, ssa_name_values, SSA_NAME_VERSION(x)) \
 817      : NULL_TREE)
 818 extern void set_ssa_name_value (tree, tree);
 819 extern bool potentially_threadable_block (basic_block);
 820 extern void thread_across_edge (gimple, edge, bool,
 821                                 VEC(tree, heap) **, tree (*) (gimple, gimple));
 822
 823 /* In tree-ssa-loop-im.c  */
 824 /* The possibilities of statement movement.  */
 825
 826 enum move_pos
 827   {
 828     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 829     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 830                                    become executed -- memory accesses, ... */
 831     MOVE_POSSIBLE               /* Unlimited movement.  */
 832   };
 833 extern enum move_pos movement_possibility (gimple);
 834 char *get_lsm_tmp_name (tree, unsigned);
 835
 836 /* In tree-flow-inline.h  */
 837 static inline bool is_call_clobbered (const_tree);
 838 static inline void set_is_used (tree);
 839 static inline bool unmodifiable_var_p (const_tree);
 840 static inline bool ref_contains_array_ref (const_tree);
 841 static inline bool array_ref_contains_indirect_ref (const_tree);
 842
 843 /* In tree-eh.c  */
 844 extern void make_eh_edges (gimple);
 845 extern bool make_eh_dispatch_edges (gimple);
 846 extern edge redirect_eh_edge (edge, basic_block);
 847 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 848 extern bool tree_could_trap_p (tree);
 849 extern bool operation_could_trap_helper_p (enum tree_code, bool, bool, bool,
 850                                            bool, tree, bool *);
 851 extern bool operation_could_trap_p (enum tree_code, bool, bool, tree);
 852 extern bool stmt_could_throw_p (gimple);
 853 extern bool tree_could_throw_p (tree);
 854 extern bool stmt_can_throw_internal (gimple);
 855 extern bool stmt_can_throw_external (gimple);
 856 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 857 extern void add_stmt_to_eh_lp (gimple, int);
 858 extern bool remove_stmt_from_eh_lp (gimple);
 859 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 860 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 861 extern int lookup_expr_eh_lp (tree);
 862 extern int lookup_stmt_eh_lp (gimple);
 863 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 864 extern bool maybe_clean_eh_stmt (gimple);
 865 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 866 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 867                                         struct function *, gimple,
 868                                         struct pointer_map_t *, int);
 869 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 870 extern bool verify_eh_edges (gimple);
 871 extern bool verify_eh_dispatch_edge (gimple);
 872
 873 /* In tree-ssa-pre.c  */
 874 struct pre_expr_d;
 875 void add_to_value (unsigned int, struct pre_expr_d *);
 876 void debug_value_expressions (unsigned int);
 877 void print_value_expressions (FILE *, unsigned int);
 878
 879 /* In tree-ssa-sink.c  */
 880 bool is_hidden_global_store (gimple);
 881
 882 /* In tree-loop-linear.c  */
 883 extern void linear_transform_loops (void);
 884 extern unsigned perfect_loop_nest_depth (struct loop *);
 885
 886 /* In graphite.c  */
 887 extern void graphite_transform_loops (void);
 888
 889 /* In tree-data-ref.c  */
 890 extern void tree_check_data_deps (void);
 891
 892 /* In tree-ssa-loop-ivopts.c  */
 893 bool expr_invariant_in_loop_p (struct loop *, tree);
 894 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 895 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode);
 896 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode, bool);
 897
 898 /* In tree-ssa-threadupdate.c.  */
 899 extern bool thread_through_all_blocks (bool);
 900 extern void register_jump_thread (edge, edge);
 901
 902 /* In gimplify.c  */
 903 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 904 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 905                                bool, enum gsi_iterator_update);
 906 tree gimple_fold_indirect_ref (tree);
 907
 908 /* In tree-ssa-live.c */
 909 extern void remove_unused_locals (void);
 910 extern void dump_scope_blocks (FILE *, int);
 911 extern void debug_scope_blocks (int);
 912 extern void debug_scope_block (tree, int);
 913
 914 /* In tree-ssa-address.c  */
 915
 916 /* Description of a memory address.  */
 917
 918 struct mem_address
 919 {
 920   tree symbol, base, index, step, offset;
 921 };
 922
 923 struct affine_tree_combination;
 924 tree create_mem_ref (gimple_stmt_iterator *, tree,
 925                      struct affine_tree_combination *, bool);
 926 rtx addr_for_mem_ref (struct mem_address *, bool);
 927 void get_address_description (tree, struct mem_address *);
 928 tree maybe_fold_tmr (tree);
 929
 930 unsigned int execute_free_datastructures (void);
 931 unsigned int execute_fixup_cfg (void);
 932
 933 #include "tree-flow-inline.h"
 934
 935 void swap_tree_operands (gimple, tree *, tree *);
 936
 937 int least_common_multiple (int, int);
 938
 939 #endif /* _TREE_FLOW_H  */