gcc/tree-flow.h

   1 /* Data and Control Flow Analysis for Trees.
   2    Copyright (C) 2001-2013 Free Software Foundation, Inc.
   3    Contributed by Diego Novillo <dnovillo@redhat.com>
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #ifndef _TREE_FLOW_H
  22 #define _TREE_FLOW_H 1
  23
  24 #include "bitmap.h"
  25 #include "sbitmap.h"
  26 #include "basic-block.h"
  27 #include "hashtab.h"
  28 #include "gimple.h"
  29 #include "tree-ssa-operands.h"
  30 #include "cgraph.h"
  31 #include "ipa-reference.h"
  32 #include "tree-ssa-alias.h"
  33
  34
  35 /* This structure is used to map a gimple statement to a label,
  36    or list of labels to represent transaction restart.  */
  37
  38 struct GTY(()) tm_restart_node {
  39   gimple stmt;
  40   tree label_or_list;
  41 };
  42
  43 /* Gimple dataflow datastructure. All publicly available fields shall have
  44    gimple_ accessor defined in tree-flow-inline.h, all publicly modifiable
  45    fields should have gimple_set accessor.  */
  46 struct GTY(()) gimple_df {
  47   /* A vector of all the noreturn calls passed to modify_stmt.
  48      cleanup_control_flow uses it to detect cases where a mid-block
  49      indirect call has been turned into a noreturn call.  When this
  50      happens, all the instructions after the call are no longer
  51      reachable and must be deleted as dead.  */
  52   vec<gimple, va_gc> *modified_noreturn_calls;
  53
  54   /* Array of all SSA_NAMEs used in the function.  */
  55   vec<tree, va_gc> *ssa_names;
  56
  57   /* Artificial variable used for the virtual operand FUD chain.  */
  58   tree vop;
  59
  60   /* The PTA solution for the ESCAPED artificial variable.  */
  61   struct pt_solution escaped;
  62
  63   /* A map of decls to artificial ssa-names that point to the partition
  64      of the decl.  */
  65   struct pointer_map_t * GTY((skip(""))) decls_to_pointers;
  66
  67   /* Free list of SSA_NAMEs.  */
  68   vec<tree, va_gc> *free_ssanames;
  69
  70   /* Hashtable holding definition for symbol.  If this field is not NULL, it
  71      means that the first reference to this variable in the function is a
  72      USE or a VUSE.  In those cases, the SSA renamer creates an SSA name
  73      for this variable with an empty defining statement.  */
  74   htab_t GTY((param_is (union tree_node))) default_defs;
  75
  76   /* True if there are any symbols that need to be renamed.  */
  77   unsigned int ssa_renaming_needed : 1;
  78
  79   /* True if all virtual operands need to be renamed.  */
  80   unsigned int rename_vops : 1;
  81
  82   /* True if the code is in ssa form.  */
  83   unsigned int in_ssa_p : 1;
  84
  85   /* True if IPA points-to information was computed for this function.  */
  86   unsigned int ipa_pta : 1;
  87
  88   struct ssa_operands ssa_operands;
  89
  90   /* Map gimple stmt to tree label (or list of labels) for transaction
  91      restart and abort.  */
  92   htab_t GTY ((param_is (struct tm_restart_node))) tm_restart;
  93 };
  94
  95
  96 typedef struct
  97 {
  98   htab_t htab;
  99   PTR *slot;
 100   PTR *limit;
 101 } htab_iterator;
 102
 103 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
 104    storing each element in RESULT, which is of type TYPE.  */
 105 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
 106   for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
 107         !end_htab_p (&(ITER)); \
 108         RESULT = (TYPE) next_htab_element (&(ITER)))
 109
 110 /* It is advantageous to avoid things like life analysis for variables which
 111    do not need PHI nodes.  This enum describes whether or not a particular
 112    variable may need a PHI node.  */
 113
 114 enum need_phi_state {
 115   /* This is the default.  If we are still in this state after finding
 116      all the definition and use sites, then we will assume the variable
 117      needs PHI nodes.  This is probably an overly conservative assumption.  */
 118   NEED_PHI_STATE_UNKNOWN,
 119
 120   /* This state indicates that we have seen one or more sets of the
 121      variable in a single basic block and that the sets dominate all
 122      uses seen so far.  If after finding all definition and use sites
 123      we are still in this state, then the variable does not need any
 124      PHI nodes.  */
 125   NEED_PHI_STATE_NO,
 126
 127   /* This state indicates that we have either seen multiple definitions of
 128      the variable in multiple blocks, or that we encountered a use in a
 129      block that was not dominated by the block containing the set(s) of
 130      this variable.  This variable is assumed to need PHI nodes.  */
 131   NEED_PHI_STATE_MAYBE
 132 };
 133
 134
 135 /* Immediate use lists are used to directly access all uses for an SSA
 136    name and get pointers to the statement for each use.
 137
 138    The structure ssa_use_operand_d consists of PREV and NEXT pointers
 139    to maintain the list.  A USE pointer, which points to address where
 140    the use is located and a LOC pointer which can point to the
 141    statement where the use is located, or, in the case of the root
 142    node, it points to the SSA name itself.
 143
 144    The list is anchored by an occurrence of ssa_operand_d *in* the
 145    ssa_name node itself (named 'imm_uses').  This node is uniquely
 146    identified by having a NULL USE pointer. and the LOC pointer
 147    pointing back to the ssa_name node itself.  This node forms the
 148    base for a circular list, and initially this is the only node in
 149    the list.
 150
 151    Fast iteration allows each use to be examined, but does not allow
 152    any modifications to the uses or stmts.
 153
 154    Normal iteration allows insertion, deletion, and modification. the
 155    iterator manages this by inserting a marker node into the list
 156    immediately before the node currently being examined in the list.
 157    this marker node is uniquely identified by having null stmt *and* a
 158    null use pointer.
 159
 160    When iterating to the next use, the iteration routines check to see
 161    if the node after the marker has changed. if it has, then the node
 162    following the marker is now the next one to be visited. if not, the
 163    marker node is moved past that node in the list (visualize it as
 164    bumping the marker node through the list).  this continues until
 165    the marker node is moved to the original anchor position. the
 166    marker node is then removed from the list.
 167
 168    If iteration is halted early, the marker node must be removed from
 169    the list before continuing.  */
 170 typedef struct immediate_use_iterator_d
 171 {
 172   /* This is the current use the iterator is processing.  */
 173   ssa_use_operand_t *imm_use;
 174   /* This marks the last use in the list (use node from SSA_NAME)  */
 175   ssa_use_operand_t *end_p;
 176   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 177   ssa_use_operand_t iter_node;
 178   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 179      the next one is traversed to, so it must be cached early.  */
 180   ssa_use_operand_t *next_imm_name;
 181 } imm_use_iterator;
 182
 183
 184 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 185    modifying stmts will cause this iterator to malfunction.  */
 186
 187 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)               \
 188   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 189        !end_readonly_imm_use_p (&(ITER));                       \
 190        (void) ((DEST) = next_readonly_imm_use (&(ITER))))
 191
 192 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 193
 194 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 195   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 196        !end_imm_use_stmt_p (&(ITER));                           \
 197        (void) ((STMT) = next_imm_use_stmt (&(ITER))))
 198
 199 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 200    do so will result in leaving a iterator marker node in the immediate
 201    use list, and nothing good will come from that.   */
 202 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 203    {                                                            \
 204      end_imm_use_stmt_traverse (&(ITER));                       \
 205      break;                                                     \
 206    }
 207
 208
 209 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 210    get access to each occurrence of ssavar on the stmt returned by
 211    that iterator..  for instance:
 212
 213      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 214        {
 215          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 216            {
 217              SET_USE (use_p, blah);
 218            }
 219          update_stmt (stmt);
 220        }                                                         */
 221
 222 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 223   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 224        !end_imm_use_on_stmt_p (&(ITER));                        \
 225        (void) ((DEST) = next_imm_use_on_stmt (&(ITER))))
 226
 227
 228
 229 static inline void update_stmt (gimple);
 230 static inline int get_lineno (const_gimple);
 231
 232 /* Accessors for basic block annotations.  */
 233 static inline gimple_seq phi_nodes (const_basic_block);
 234 static inline void set_phi_nodes (basic_block, gimple_seq);
 235
 236 /*---------------------------------------------------------------------------
 237                               Global declarations
 238 ---------------------------------------------------------------------------*/
 239 struct int_tree_map {
 240   unsigned int uid;
 241   tree to;
 242 };
 243
 244 /* Macros for showing usage statistics.  */
 245 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 246                   ? (x)                                 \
 247                   : ((x) < 1024*1024*10                 \
 248                      ? (x) / 1024                       \
 249                      : (x) / (1024*1024))))
 250
 251 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 252
 253 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 254
 255 /*---------------------------------------------------------------------------
 256                               OpenMP Region Tree
 257 ---------------------------------------------------------------------------*/
 258
 259 /* Parallel region information.  Every parallel and workshare
 260    directive is enclosed between two markers, the OMP_* directive
 261    and a corresponding OMP_RETURN statement.  */
 262
 263 struct omp_region
 264 {
 265   /* The enclosing region.  */
 266   struct omp_region *outer;
 267
 268   /* First child region.  */
 269   struct omp_region *inner;
 270
 271   /* Next peer region.  */
 272   struct omp_region *next;
 273
 274   /* Block containing the omp directive as its last stmt.  */
 275   basic_block entry;
 276
 277   /* Block containing the OMP_RETURN as its last stmt.  */
 278   basic_block exit;
 279
 280   /* Block containing the OMP_CONTINUE as its last stmt.  */
 281   basic_block cont;
 282
 283   /* If this is a combined parallel+workshare region, this is a list
 284      of additional arguments needed by the combined parallel+workshare
 285      library call.  */
 286   vec<tree, va_gc> *ws_args;
 287
 288   /* The code for the omp directive of this region.  */
 289   enum gimple_code type;
 290
 291   /* Schedule kind, only used for OMP_FOR type regions.  */
 292   enum omp_clause_schedule_kind sched_kind;
 293
 294   /* True if this is a combined parallel+workshare region.  */
 295   bool is_combined_parallel;
 296 };
 297
 298 extern struct omp_region *root_omp_region;
 299 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 300                                           struct omp_region *);
 301 extern void free_omp_regions (void);
 302 void omp_expand_local (basic_block);
 303 tree copy_var_decl (tree, tree, tree);
 304
 305 /*---------------------------------------------------------------------------
 306                               Function prototypes
 307 ---------------------------------------------------------------------------*/
 308 /* In tree-cfg.c  */
 309
 310 /* Location to track pending stmt for edge insertion.  */
 311 #define PENDING_STMT(e) ((e)->insns.g)
 312
 313 extern void delete_tree_cfg_annotations (void);
 314 extern bool stmt_ends_bb_p (gimple);
 315 extern bool is_ctrl_stmt (gimple);
 316 extern bool is_ctrl_altering_stmt (gimple);
 317 extern bool simple_goto_p (gimple);
 318 extern bool stmt_can_make_abnormal_goto (gimple);
 319 extern basic_block single_noncomplex_succ (basic_block bb);
 320 extern void gimple_dump_bb (FILE *, basic_block, int, int);
 321 extern void gimple_debug_bb (basic_block);
 322 extern basic_block gimple_debug_bb_n (int);
 323 extern void gimple_dump_cfg (FILE *, int);
 324 extern void gimple_debug_cfg (int);
 325 extern void dump_cfg_stats (FILE *);
 326 extern void dot_cfg (void);
 327 extern void debug_cfg_stats (void);
 328 extern void debug_loops (int);
 329 extern void debug_loop (struct loop *, int);
 330 extern void debug (struct loop &ref);
 331 extern void debug (struct loop *ptr);
 332 extern void debug_verbose (struct loop &ref);
 333 extern void debug_verbose (struct loop *ptr);
 334 extern void debug_loop_num (unsigned, int);
 335 extern void print_loops (FILE *, int);
 336 extern void print_loops_bb (FILE *, basic_block, int, int);
 337 extern void cleanup_dead_labels (void);
 338 extern void group_case_labels_stmt (gimple);
 339 extern void group_case_labels (void);
 340 extern gimple first_stmt (basic_block);
 341 extern gimple last_stmt (basic_block);
 342 extern gimple last_and_only_stmt (basic_block);
 343 extern edge find_taken_edge (basic_block, tree);
 344 extern basic_block label_to_block_fn (struct function *, tree);
 345 #define label_to_block(t) (label_to_block_fn (cfun, t))
 346 extern void notice_special_calls (gimple);
 347 extern void clear_special_calls (void);
 348 extern void verify_gimple_in_seq (gimple_seq);
 349 extern void verify_gimple_in_cfg (struct function *);
 350 extern tree gimple_block_label (basic_block);
 351 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 352 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 353                                         basic_block *, bool);
 354 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 355                                       basic_block *);
 356 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 357                                           vec<basic_block> *bbs_p);
 358 extern void add_phi_args_after_copy_bb (basic_block);
 359 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 360 extern bool gimple_purge_dead_eh_edges (basic_block);
 361 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 362 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 363 extern bool gimple_purge_all_dead_abnormal_call_edges (const_bitmap);
 364 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 365                              tree, tree);
 366 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 367                              tree, tree, tree);
 368 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 369                              tree, tree, tree, tree);
 370 extern void init_empty_tree_cfg (void);
 371 extern void init_empty_tree_cfg_for_function (struct function *);
 372 extern void fold_cond_expr_cond (void);
 373 extern void make_abnormal_goto_edges (basic_block, bool);
 374 extern void replace_uses_by (tree, tree);
 375 extern void start_recording_case_labels (void);
 376 extern void end_recording_case_labels (void);
 377 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 378                                            basic_block, tree);
 379 void remove_edge_and_dominated_blocks (edge);
 380 bool tree_node_can_be_shared (tree);
 381
 382 /* In tree-cfgcleanup.c  */
 383 extern bitmap cfgcleanup_altered_bbs;
 384 extern bool cleanup_tree_cfg (void);
 385
 386 /* In tree-pretty-print.c.  */
 387 extern void dump_generic_bb (FILE *, basic_block, int, int);
 388 extern int op_code_prio (enum tree_code);
 389 extern int op_prio (const_tree);
 390 extern const char *op_symbol_code (enum tree_code);
 391
 392 /* In tree-dfa.c  */
 393 extern void renumber_gimple_stmt_uids (void);
 394 extern void renumber_gimple_stmt_uids_in_blocks (basic_block *, int);
 395 extern void dump_dfa_stats (FILE *);
 396 extern void debug_dfa_stats (void);
 397 extern void dump_variable (FILE *, tree);
 398 extern void debug_variable (tree);
 399 extern void set_ssa_default_def (struct function *, tree, tree);
 400 extern tree ssa_default_def (struct function *, tree);
 401 extern tree get_or_create_ssa_default_def (struct function *, tree);
 402 extern bool stmt_references_abnormal_ssa_name (gimple);
 403 extern tree get_addr_base_and_unit_offset (tree, HOST_WIDE_INT *);
 404 extern void dump_enumerated_decls (FILE *, int);
 405
 406 /* In tree-phinodes.c  */
 407 extern void reserve_phi_args_for_new_edge (basic_block);
 408 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 409 extern gimple create_phi_node (tree, basic_block);
 410 extern void add_phi_arg (gimple, tree, edge, source_location);
 411 extern void remove_phi_args (edge);
 412 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 413 extern void remove_phi_nodes (basic_block);
 414 extern void release_phi_node (gimple);
 415 extern void phinodes_print_statistics (void);
 416
 417 /* In gimple-low.c  */
 418 extern void record_vars_into (tree, tree);
 419 extern void record_vars (tree);
 420 extern bool gimple_seq_may_fallthru (gimple_seq);
 421 extern bool gimple_stmt_may_fallthru (gimple);
 422 extern bool gimple_check_call_matching_types (gimple, tree, bool);
 423
 424 /* In tree-into-ssa.c  */
 425 void update_ssa (unsigned);
 426 void delete_update_ssa (void);
 427 tree create_new_def_for (tree, gimple, def_operand_p);
 428 bool need_ssa_update_p (struct function *);
 429 bool name_registered_for_update_p (tree);
 430 void release_ssa_name_after_update_ssa (tree);
 431 void mark_virtual_operands_for_renaming (struct function *);
 432 tree get_current_def (tree);
 433 void set_current_def (tree, tree);
 434
 435 /* In tree-ssa-ccp.c  */
 436 tree fold_const_aggregate_ref (tree);
 437 tree gimple_fold_stmt_to_constant (gimple, tree (*)(tree));
 438
 439 /* In tree-ssa-dom.c  */
 440 extern void dump_dominator_optimization_stats (FILE *);
 441 extern void debug_dominator_optimization_stats (void);
 442 int loop_depth_of_name (tree);
 443 tree degenerate_phi_result (gimple);
 444 bool simple_iv_increment_p (gimple);
 445
 446 /* In tree-ssa-copy.c  */
 447 extern void propagate_value (use_operand_p, tree);
 448 extern void propagate_tree_value (tree *, tree);
 449 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 450 extern void replace_exp (use_operand_p, tree);
 451 extern bool may_propagate_copy (tree, tree);
 452 extern bool may_propagate_copy_into_stmt (gimple, tree);
 453 extern bool may_propagate_copy_into_asm (tree);
 454
 455 /* In tree-ssa-loop-ch.c  */
 456 bool do_while_loop_p (struct loop *);
 457
 458 /* Affine iv.  */
 459
 460 typedef struct
 461 {
 462   /* Iv = BASE + STEP * i.  */
 463   tree base, step;
 464
 465   /* True if this iv does not overflow.  */
 466   bool no_overflow;
 467 } affine_iv;
 468
 469 /* Description of number of iterations of a loop.  All the expressions inside
 470    the structure can be evaluated at the end of the loop's preheader
 471    (and due to ssa form, also anywhere inside the body of the loop).  */
 472
 473 struct tree_niter_desc
 474 {
 475   tree assumptions;     /* The boolean expression.  If this expression evaluates
 476                            to false, then the other fields in this structure
 477                            should not be used; there is no guarantee that they
 478                            will be correct.  */
 479   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 480                            the loop will exit in the first iteration (i.e.
 481                            its latch will not be executed), even if the niter
 482                            field says otherwise.  */
 483   tree niter;           /* The expression giving the number of iterations of
 484                            a loop (provided that assumptions == true and
 485                            may_be_zero == false), more precisely the number
 486                            of executions of the latch of the loop.  */
 487   double_int max;       /* The upper bound on the number of iterations of
 488                            the loop.  */
 489
 490   /* The simplified shape of the exit condition.  The loop exits if
 491      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 492      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 493      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 494      by loop unrolling.  */
 495   affine_iv control;
 496   tree bound;
 497   enum tree_code cmp;
 498 };
 499
 500 /* In tree-ssa-phiopt.c */
 501 bool empty_block_p (basic_block);
 502 basic_block *blocks_in_phiopt_order (void);
 503 bool nonfreeing_call_p (gimple);
 504
 505 /* In tree-ssa-loop*.c  */
 506
 507 unsigned int tree_ssa_lim (void);
 508 unsigned int tree_ssa_unswitch_loops (void);
 509 unsigned int canonicalize_induction_variables (void);
 510 unsigned int tree_unroll_loops_completely (bool, bool);
 511 unsigned int tree_ssa_prefetch_arrays (void);
 512 void tree_ssa_iv_optimize (void);
 513 unsigned tree_predictive_commoning (void);
 514 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 515 bool parallelize_loops (void);
 516
 517 bool loop_only_exit_p (const struct loop *, const_edge);
 518 bool number_of_iterations_exit (struct loop *, edge,
 519                                 struct tree_niter_desc *niter, bool,
 520                                 bool every_iteration = true);
 521 tree find_loop_niter (struct loop *, edge *);
 522 tree loop_niter_by_eval (struct loop *, edge);
 523 tree find_loop_niter_by_eval (struct loop *, edge *);
 524 void estimate_numbers_of_iterations (void);
 525 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 526 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 527
 528 bool nowrap_type_p (tree);
 529 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 530 enum ev_direction scev_direction (const_tree);
 531
 532 void free_numbers_of_iterations_estimates (void);
 533 void free_numbers_of_iterations_estimates_loop (struct loop *);
 534 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 535 void verify_loop_closed_ssa (bool);
 536 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 537 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 538                 tree *, tree *);
 539 basic_block split_loop_exit_edge (edge);
 540 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 541                                      bool *);
 542 basic_block ip_end_pos (struct loop *);
 543 basic_block ip_normal_pos (struct loop *);
 544 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 545                                          unsigned int, sbitmap,
 546                                          edge, vec<edge> *,
 547                                          int);
 548 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 549 tree expand_simple_operations (tree);
 550 void substitute_in_loop_info (struct loop *, tree, tree);
 551 edge single_dom_exit (struct loop *);
 552 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 553                         struct tree_niter_desc *niter);
 554 void tree_unroll_loop (struct loop *, unsigned,
 555                        edge, struct tree_niter_desc *);
 556 typedef void (*transform_callback)(struct loop *, void *);
 557 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 558                                      edge, struct tree_niter_desc *,
 559                                      transform_callback, void *);
 560 bool contains_abnormal_ssa_name_p (tree);
 561 bool stmt_dominates_stmt_p (gimple, gimple);
 562
 563 /* In tree-ssa-dce.c */
 564 void mark_virtual_operand_for_renaming (tree);
 565 void mark_virtual_phi_result_for_renaming (gimple);
 566
 567 /* In tree-ssa-threadedge.c */
 568 extern void threadedge_initialize_values (void);
 569 extern void threadedge_finalize_values (void);
 570 extern vec<tree> ssa_name_values;
 571 #define SSA_NAME_VALUE(x) \
 572     (SSA_NAME_VERSION(x) < ssa_name_values.length () \
 573      ? ssa_name_values[SSA_NAME_VERSION(x)] \
 574      : NULL_TREE)
 575 extern void set_ssa_name_value (tree, tree);
 576 extern bool potentially_threadable_block (basic_block);
 577 extern void thread_across_edge (gimple, edge, bool,
 578                                 vec<tree> *, tree (*) (gimple, gimple));
 579 extern void propagate_threaded_block_debug_into (basic_block, basic_block);
 580
 581 /* In tree-ssa-loop-im.c  */
 582 /* The possibilities of statement movement.  */
 583
 584 enum move_pos
 585   {
 586     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 587     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 588                                    become executed -- memory accesses, ... */
 589     MOVE_POSSIBLE               /* Unlimited movement.  */
 590   };
 591 extern enum move_pos movement_possibility (gimple);
 592 char *get_lsm_tmp_name (tree, unsigned);
 593
 594 /* In tree-flow-inline.h  */
 595 static inline bool unmodifiable_var_p (const_tree);
 596 static inline bool ref_contains_array_ref (const_tree);
 597
 598 /* In tree-eh.c  */
 599 extern void make_eh_edges (gimple);
 600 extern bool make_eh_dispatch_edges (gimple);
 601 extern edge redirect_eh_edge (edge, basic_block);
 602 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 603 extern bool stmt_could_throw_p (gimple);
 604 extern bool stmt_can_throw_internal (gimple);
 605 extern bool stmt_can_throw_external (gimple);
 606 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 607 extern void add_stmt_to_eh_lp (gimple, int);
 608 extern bool remove_stmt_from_eh_lp (gimple);
 609 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 610 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 611 extern int lookup_stmt_eh_lp (gimple);
 612 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 613 extern bool maybe_clean_eh_stmt (gimple);
 614 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 615 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 616                                         struct function *, gimple,
 617                                         struct pointer_map_t *, int);
 618 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 619 extern bool verify_eh_edges (gimple);
 620 extern bool verify_eh_dispatch_edge (gimple);
 621 extern void maybe_remove_unreachable_handlers (void);
 622
 623 /* In tree-ssa-pre.c  */
 624 void debug_value_expressions (unsigned int);
 625
 626 /* In tree-loop-linear.c  */
 627 extern void linear_transform_loops (void);
 628 extern unsigned perfect_loop_nest_depth (struct loop *);
 629
 630 /* In graphite.c  */
 631 extern void graphite_transform_loops (void);
 632
 633 /* In tree-data-ref.c  */
 634 extern void tree_check_data_deps (void);
 635
 636 /* In tree-ssa-loop-ivopts.c  */
 637 bool expr_invariant_in_loop_p (struct loop *, tree);
 638 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 639 struct loop *outermost_invariant_loop_for_expr (struct loop *, tree);
 640 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 641                                       addr_space_t);
 642 bool may_be_nonaddressable_p (tree expr);
 643
 644 /* In tree-ssa-threadupdate.c.  */
 645 extern bool thread_through_all_blocks (bool);
 646 extern void register_jump_thread (vec<edge>, bool);
 647
 648 /* In gimplify.c  */
 649 tree force_gimple_operand_1 (tree, gimple_seq *, gimple_predicate, tree);
 650 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 651 tree force_gimple_operand_gsi_1 (gimple_stmt_iterator *, tree,
 652                                  gimple_predicate, tree,
 653                                  bool, enum gsi_iterator_update);
 654 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 655                                bool, enum gsi_iterator_update);
 656 tree gimple_fold_indirect_ref (tree);
 657
 658 /* In tree-ssa-live.c */
 659 extern void remove_unused_locals (void);
 660 extern void dump_scope_blocks (FILE *, int);
 661 extern void debug_scope_blocks (int);
 662 extern void debug_scope_block (tree, int);
 663
 664 /* In tree-ssa-address.c  */
 665
 666 /* Description of a memory address.  */
 667
 668 struct mem_address
 669 {
 670   tree symbol, base, index, step, offset;
 671 };
 672
 673 struct affine_tree_combination;
 674 tree create_mem_ref (gimple_stmt_iterator *, tree,
 675                      struct affine_tree_combination *, tree, tree, tree, bool);
 676 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 677 void get_address_description (tree, struct mem_address *);
 678 tree maybe_fold_tmr (tree);
 679
 680 unsigned int execute_fixup_cfg (void);
 681 bool fixup_noreturn_call (gimple stmt);
 682
 683 /* In ipa-pure-const.c  */
 684 void warn_function_noreturn (tree);
 685
 686 /* In tree-ssa-ter.c  */
 687 bool stmt_is_replaceable_p (gimple);
 688
 689 /* In tree-parloops.c  */
 690 bool parallelized_function_p (tree);
 691
 692 #include "tree-flow-inline.h"
 693
 694 void swap_tree_operands (gimple, tree *, tree *);
 695
 696 #endif /* _TREE_FLOW_H  */