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 /* Accessors for internal use only.  Generic code should use abstraction
  96    provided by tree-flow-inline.h or specific modules.  */
  97 #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames
  98 #define SSANAMES(fun) (fun)->gimple_df->ssa_names
  99 #define MODIFIED_NORETURN_CALLS(fun) (fun)->gimple_df->modified_noreturn_calls
 100 #define DEFAULT_DEFS(fun) (fun)->gimple_df->default_defs
 101
 102 typedef struct
 103 {
 104   htab_t htab;
 105   PTR *slot;
 106   PTR *limit;
 107 } htab_iterator;
 108
 109 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
 110    storing each element in RESULT, which is of type TYPE.  */
 111 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
 112   for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
 113         !end_htab_p (&(ITER)); \
 114         RESULT = (TYPE) next_htab_element (&(ITER)))
 115
 116 /*---------------------------------------------------------------------------
 117                       Attributes for SSA_NAMEs.
 118
 119   NOTE: These structures are stored in struct tree_ssa_name
 120   but are only used by the tree optimizers, so it makes better sense
 121   to declare them here to avoid recompiling unrelated files when
 122   making changes.
 123 ---------------------------------------------------------------------------*/
 124
 125 /* Aliasing information for SSA_NAMEs representing pointer variables.  */
 126
 127 struct GTY(()) ptr_info_def
 128 {
 129   /* The points-to solution.  */
 130   struct pt_solution pt;
 131
 132   /* Alignment and misalignment of the pointer in bytes.  Together
 133      align and misalign specify low known bits of the pointer.
 134      ptr & (align - 1) == misalign.  */
 135
 136   /* When known, this is the power-of-two byte alignment of the object this
 137      pointer points into.  This is usually DECL_ALIGN_UNIT for decls and
 138      MALLOC_ABI_ALIGNMENT for allocated storage.  When the alignment is not
 139      known, it is zero.  Do not access directly but use functions
 140      get_ptr_info_alignment, set_ptr_info_alignment,
 141      mark_ptr_info_alignment_unknown and similar.  */
 142   unsigned int align;
 143
 144   /* When alignment is known, the byte offset this pointer differs from the
 145      above alignment.  Access only through the same helper functions as align
 146      above.  */
 147   unsigned int misalign;
 148 };
 149
 150
 151 /* It is advantageous to avoid things like life analysis for variables which
 152    do not need PHI nodes.  This enum describes whether or not a particular
 153    variable may need a PHI node.  */
 154
 155 enum need_phi_state {
 156   /* This is the default.  If we are still in this state after finding
 157      all the definition and use sites, then we will assume the variable
 158      needs PHI nodes.  This is probably an overly conservative assumption.  */
 159   NEED_PHI_STATE_UNKNOWN,
 160
 161   /* This state indicates that we have seen one or more sets of the
 162      variable in a single basic block and that the sets dominate all
 163      uses seen so far.  If after finding all definition and use sites
 164      we are still in this state, then the variable does not need any
 165      PHI nodes.  */
 166   NEED_PHI_STATE_NO,
 167
 168   /* This state indicates that we have either seen multiple definitions of
 169      the variable in multiple blocks, or that we encountered a use in a
 170      block that was not dominated by the block containing the set(s) of
 171      this variable.  This variable is assumed to need PHI nodes.  */
 172   NEED_PHI_STATE_MAYBE
 173 };
 174
 175
 176 /* Immediate use lists are used to directly access all uses for an SSA
 177    name and get pointers to the statement for each use.
 178
 179    The structure ssa_use_operand_d consists of PREV and NEXT pointers
 180    to maintain the list.  A USE pointer, which points to address where
 181    the use is located and a LOC pointer which can point to the
 182    statement where the use is located, or, in the case of the root
 183    node, it points to the SSA name itself.
 184
 185    The list is anchored by an occurrence of ssa_operand_d *in* the
 186    ssa_name node itself (named 'imm_uses').  This node is uniquely
 187    identified by having a NULL USE pointer. and the LOC pointer
 188    pointing back to the ssa_name node itself.  This node forms the
 189    base for a circular list, and initially this is the only node in
 190    the list.
 191
 192    Fast iteration allows each use to be examined, but does not allow
 193    any modifications to the uses or stmts.
 194
 195    Normal iteration allows insertion, deletion, and modification. the
 196    iterator manages this by inserting a marker node into the list
 197    immediately before the node currently being examined in the list.
 198    this marker node is uniquely identified by having null stmt *and* a
 199    null use pointer.
 200
 201    When iterating to the next use, the iteration routines check to see
 202    if the node after the marker has changed. if it has, then the node
 203    following the marker is now the next one to be visited. if not, the
 204    marker node is moved past that node in the list (visualize it as
 205    bumping the marker node through the list).  this continues until
 206    the marker node is moved to the original anchor position. the
 207    marker node is then removed from the list.
 208
 209    If iteration is halted early, the marker node must be removed from
 210    the list before continuing.  */
 211 typedef struct immediate_use_iterator_d
 212 {
 213   /* This is the current use the iterator is processing.  */
 214   ssa_use_operand_t *imm_use;
 215   /* This marks the last use in the list (use node from SSA_NAME)  */
 216   ssa_use_operand_t *end_p;
 217   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 218   ssa_use_operand_t iter_node;
 219   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 220      the next one is traversed to, so it must be cached early.  */
 221   ssa_use_operand_t *next_imm_name;
 222 } imm_use_iterator;
 223
 224
 225 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 226    modifying stmts will cause this iterator to malfunction.  */
 227
 228 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)               \
 229   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 230        !end_readonly_imm_use_p (&(ITER));                       \
 231        (void) ((DEST) = next_readonly_imm_use (&(ITER))))
 232
 233 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 234
 235 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 236   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 237        !end_imm_use_stmt_p (&(ITER));                           \
 238        (void) ((STMT) = next_imm_use_stmt (&(ITER))))
 239
 240 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 241    do so will result in leaving a iterator marker node in the immediate
 242    use list, and nothing good will come from that.   */
 243 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 244    {                                                            \
 245      end_imm_use_stmt_traverse (&(ITER));                       \
 246      break;                                                     \
 247    }
 248
 249
 250 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 251    get access to each occurrence of ssavar on the stmt returned by
 252    that iterator..  for instance:
 253
 254      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 255        {
 256          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 257            {
 258              SET_USE (use_p, blah);
 259            }
 260          update_stmt (stmt);
 261        }                                                         */
 262
 263 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 264   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 265        !end_imm_use_on_stmt_p (&(ITER));                        \
 266        (void) ((DEST) = next_imm_use_on_stmt (&(ITER))))
 267
 268
 269
 270 static inline void update_stmt (gimple);
 271 static inline int get_lineno (const_gimple);
 272
 273 /* Accessors for basic block annotations.  */
 274 static inline gimple_seq phi_nodes (const_basic_block);
 275 static inline void set_phi_nodes (basic_block, gimple_seq);
 276
 277 /*---------------------------------------------------------------------------
 278                               Global declarations
 279 ---------------------------------------------------------------------------*/
 280 struct int_tree_map {
 281   unsigned int uid;
 282   tree to;
 283 };
 284
 285 extern unsigned int int_tree_map_hash (const void *);
 286 extern int int_tree_map_eq (const void *, const void *);
 287
 288 extern unsigned int uid_decl_map_hash (const void *);
 289 extern int uid_decl_map_eq (const void *, const void *);
 290
 291 #define num_ssa_names (vec_safe_length (cfun->gimple_df->ssa_names))
 292 #define ssa_name(i) ((*cfun->gimple_df->ssa_names)[(i)])
 293
 294 /* Macros for showing usage statistics.  */
 295 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 296                   ? (x)                                 \
 297                   : ((x) < 1024*1024*10                 \
 298                      ? (x) / 1024                       \
 299                      : (x) / (1024*1024))))
 300
 301 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 302
 303 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 304
 305 /*---------------------------------------------------------------------------
 306                               OpenMP Region Tree
 307 ---------------------------------------------------------------------------*/
 308
 309 /* Parallel region information.  Every parallel and workshare
 310    directive is enclosed between two markers, the OMP_* directive
 311    and a corresponding OMP_RETURN statement.  */
 312
 313 struct omp_region
 314 {
 315   /* The enclosing region.  */
 316   struct omp_region *outer;
 317
 318   /* First child region.  */
 319   struct omp_region *inner;
 320
 321   /* Next peer region.  */
 322   struct omp_region *next;
 323
 324   /* Block containing the omp directive as its last stmt.  */
 325   basic_block entry;
 326
 327   /* Block containing the OMP_RETURN as its last stmt.  */
 328   basic_block exit;
 329
 330   /* Block containing the OMP_CONTINUE as its last stmt.  */
 331   basic_block cont;
 332
 333   /* If this is a combined parallel+workshare region, this is a list
 334      of additional arguments needed by the combined parallel+workshare
 335      library call.  */
 336   vec<tree, va_gc> *ws_args;
 337
 338   /* The code for the omp directive of this region.  */
 339   enum gimple_code type;
 340
 341   /* Schedule kind, only used for OMP_FOR type regions.  */
 342   enum omp_clause_schedule_kind sched_kind;
 343
 344   /* True if this is a combined parallel+workshare region.  */
 345   bool is_combined_parallel;
 346 };
 347
 348 extern struct omp_region *root_omp_region;
 349 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 350                                           struct omp_region *);
 351 extern void free_omp_regions (void);
 352 void omp_expand_local (basic_block);
 353 extern tree find_omp_clause (tree, enum omp_clause_code);
 354 tree copy_var_decl (tree, tree, tree);
 355
 356 /*---------------------------------------------------------------------------
 357                               Function prototypes
 358 ---------------------------------------------------------------------------*/
 359 /* In tree-cfg.c  */
 360
 361 /* Location to track pending stmt for edge insertion.  */
 362 #define PENDING_STMT(e) ((e)->insns.g)
 363
 364 extern void delete_tree_cfg_annotations (void);
 365 extern bool stmt_ends_bb_p (gimple);
 366 extern bool is_ctrl_stmt (gimple);
 367 extern bool is_ctrl_altering_stmt (gimple);
 368 extern bool simple_goto_p (gimple);
 369 extern bool stmt_can_make_abnormal_goto (gimple);
 370 extern basic_block single_noncomplex_succ (basic_block bb);
 371 extern void gimple_dump_bb (FILE *, basic_block, int, int);
 372 extern void gimple_debug_bb (basic_block);
 373 extern basic_block gimple_debug_bb_n (int);
 374 extern void gimple_dump_cfg (FILE *, int);
 375 extern void gimple_debug_cfg (int);
 376 extern void dump_cfg_stats (FILE *);
 377 extern void dot_cfg (void);
 378 extern void debug_cfg_stats (void);
 379 extern void debug_loops (int);
 380 extern void debug_loop (struct loop *, int);
 381 extern void debug_loop_num (unsigned, int);
 382 extern void print_loops (FILE *, int);
 383 extern void print_loops_bb (FILE *, basic_block, int, int);
 384 extern void cleanup_dead_labels (void);
 385 extern void group_case_labels_stmt (gimple);
 386 extern void group_case_labels (void);
 387 extern gimple first_stmt (basic_block);
 388 extern gimple last_stmt (basic_block);
 389 extern gimple last_and_only_stmt (basic_block);
 390 extern edge find_taken_edge (basic_block, tree);
 391 extern basic_block label_to_block_fn (struct function *, tree);
 392 #define label_to_block(t) (label_to_block_fn (cfun, t))
 393 extern void notice_special_calls (gimple);
 394 extern void clear_special_calls (void);
 395 extern void verify_gimple_in_seq (gimple_seq);
 396 extern void verify_gimple_in_cfg (struct function *);
 397 extern tree gimple_block_label (basic_block);
 398 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 399 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 400                                         basic_block *);
 401 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 402                                       basic_block *);
 403 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 404                                           vec<basic_block> *bbs_p);
 405 extern void add_phi_args_after_copy_bb (basic_block);
 406 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 407 extern bool gimple_purge_dead_eh_edges (basic_block);
 408 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 409 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 410 extern bool gimple_purge_all_dead_abnormal_call_edges (const_bitmap);
 411 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 412                              tree, tree);
 413 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 414                              tree, tree, tree);
 415 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 416                              tree, tree, tree, tree);
 417 extern void init_empty_tree_cfg (void);
 418 extern void init_empty_tree_cfg_for_function (struct function *);
 419 extern void fold_cond_expr_cond (void);
 420 extern void make_abnormal_goto_edges (basic_block, bool);
 421 extern void replace_uses_by (tree, tree);
 422 extern void start_recording_case_labels (void);
 423 extern void end_recording_case_labels (void);
 424 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 425                                            basic_block, tree);
 426 void remove_edge_and_dominated_blocks (edge);
 427 bool tree_node_can_be_shared (tree);
 428 extern unsigned int split_critical_edges (void);
 429
 430 /* In tree-cfgcleanup.c  */
 431 extern bitmap cfgcleanup_altered_bbs;
 432 extern bool cleanup_tree_cfg (void);
 433
 434 /* In tree-pretty-print.c.  */
 435 extern void dump_generic_bb (FILE *, basic_block, int, int);
 436 extern int op_code_prio (enum tree_code);
 437 extern int op_prio (const_tree);
 438 extern const char *op_symbol_code (enum tree_code);
 439
 440 /* In tree-dfa.c  */
 441 extern void renumber_gimple_stmt_uids (void);
 442 extern void renumber_gimple_stmt_uids_in_blocks (basic_block *, int);
 443 extern void dump_dfa_stats (FILE *);
 444 extern void debug_dfa_stats (void);
 445 extern void dump_variable (FILE *, tree);
 446 extern void debug_variable (tree);
 447 extern void set_ssa_default_def (struct function *, tree, tree);
 448 extern tree ssa_default_def (struct function *, tree);
 449 extern tree get_or_create_ssa_default_def (struct function *, tree);
 450 extern bool stmt_references_abnormal_ssa_name (gimple);
 451 extern tree get_addr_base_and_unit_offset (tree, HOST_WIDE_INT *);
 452 extern void dump_enumerated_decls (FILE *, int);
 453
 454 /* In tree-phinodes.c  */
 455 extern void reserve_phi_args_for_new_edge (basic_block);
 456 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 457 extern gimple create_phi_node (tree, basic_block);
 458 extern void add_phi_arg (gimple, tree, edge, source_location);
 459 extern void remove_phi_args (edge);
 460 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 461 extern void remove_phi_nodes (basic_block);
 462 extern void release_phi_node (gimple);
 463 extern void phinodes_print_statistics (void);
 464
 465 /* In gimple-low.c  */
 466 extern void record_vars_into (tree, tree);
 467 extern void record_vars (tree);
 468 extern bool gimple_seq_may_fallthru (gimple_seq);
 469 extern bool gimple_stmt_may_fallthru (gimple);
 470 extern bool gimple_check_call_matching_types (gimple, tree);
 471
 472
 473 /* In tree-ssa.c  */
 474
 475 /* Mapping for redirected edges.  */
 476 struct _edge_var_map {
 477   tree result;                  /* PHI result.  */
 478   tree def;                     /* PHI arg definition.  */
 479   source_location locus;        /* PHI arg location.  */
 480 };
 481 typedef struct _edge_var_map edge_var_map;
 482
 483
 484 /* A vector of var maps.  */
 485 typedef vec<edge_var_map, va_heap, vl_embed> edge_var_map_vector;
 486
 487 extern void init_tree_ssa (struct function *);
 488 extern void redirect_edge_var_map_add (edge, tree, tree, source_location);
 489 extern void redirect_edge_var_map_clear (edge);
 490 extern void redirect_edge_var_map_dup (edge, edge);
 491 extern edge_var_map_vector *redirect_edge_var_map_vector (edge);
 492 extern void redirect_edge_var_map_destroy (void);
 493
 494 extern edge ssa_redirect_edge (edge, basic_block);
 495 extern void flush_pending_stmts (edge);
 496 extern void verify_ssa (bool);
 497 extern void delete_tree_ssa (void);
 498 extern bool ssa_undefined_value_p (tree);
 499 extern void warn_uninit (enum opt_code, tree, tree, tree, const char *, void *);
 500 extern unsigned int warn_uninitialized_vars (bool);
 501 extern void execute_update_addresses_taken (void);
 502
 503 /* Call-back function for walk_use_def_chains().  At each reaching
 504    definition, a function with this prototype is called.  */
 505 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *);
 506
 507 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 508
 509 void insert_debug_temps_for_defs (gimple_stmt_iterator *);
 510 void insert_debug_temp_for_var_def (gimple_stmt_iterator *, tree);
 511 void reset_debug_uses (gimple);
 512 void release_defs_bitset (bitmap toremove);
 513
 514 /* In tree-into-ssa.c  */
 515 void update_ssa (unsigned);
 516 void delete_update_ssa (void);
 517 tree create_new_def_for (tree, gimple, def_operand_p);
 518 bool need_ssa_update_p (struct function *);
 519 bool name_registered_for_update_p (tree);
 520 void release_ssa_name_after_update_ssa (tree);
 521 void mark_virtual_operands_for_renaming (struct function *);
 522 tree get_current_def (tree);
 523 void set_current_def (tree, tree);
 524
 525 /* In tree-ssanames.c  */
 526 extern void init_ssanames (struct function *, int);
 527 extern void fini_ssanames (void);
 528 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 529 extern tree copy_ssa_name_fn (struct function *, tree, gimple);
 530 extern tree duplicate_ssa_name_fn (struct function *, tree, gimple);
 531 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 532 extern void release_ssa_name (tree);
 533 extern void release_defs (gimple);
 534 extern void replace_ssa_name_symbol (tree, tree);
 535 extern bool get_ptr_info_alignment (struct ptr_info_def *, unsigned int *,
 536                                     unsigned int *);
 537 extern void mark_ptr_info_alignment_unknown (struct ptr_info_def *);
 538 extern void set_ptr_info_alignment (struct ptr_info_def *, unsigned int,
 539                                     unsigned int);
 540 extern void adjust_ptr_info_misalignment (struct ptr_info_def *,
 541                                           unsigned int);
 542
 543 extern void ssanames_print_statistics (void);
 544
 545 /* In tree-ssa-ccp.c  */
 546 tree fold_const_aggregate_ref (tree);
 547 tree gimple_fold_stmt_to_constant (gimple, tree (*)(tree));
 548
 549 /* In tree-ssa-dom.c  */
 550 extern void dump_dominator_optimization_stats (FILE *);
 551 extern void debug_dominator_optimization_stats (void);
 552 int loop_depth_of_name (tree);
 553 tree degenerate_phi_result (gimple);
 554 bool simple_iv_increment_p (gimple);
 555
 556 /* In tree-ssa-copy.c  */
 557 extern void propagate_value (use_operand_p, tree);
 558 extern void propagate_tree_value (tree *, tree);
 559 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 560 extern void replace_exp (use_operand_p, tree);
 561 extern bool may_propagate_copy (tree, tree);
 562 extern bool may_propagate_copy_into_stmt (gimple, tree);
 563 extern bool may_propagate_copy_into_asm (tree);
 564
 565 /* In tree-ssa-loop-ch.c  */
 566 bool do_while_loop_p (struct loop *);
 567
 568 /* Affine iv.  */
 569
 570 typedef struct
 571 {
 572   /* Iv = BASE + STEP * i.  */
 573   tree base, step;
 574
 575   /* True if this iv does not overflow.  */
 576   bool no_overflow;
 577 } affine_iv;
 578
 579 /* Description of number of iterations of a loop.  All the expressions inside
 580    the structure can be evaluated at the end of the loop's preheader
 581    (and due to ssa form, also anywhere inside the body of the loop).  */
 582
 583 struct tree_niter_desc
 584 {
 585   tree assumptions;     /* The boolean expression.  If this expression evaluates
 586                            to false, then the other fields in this structure
 587                            should not be used; there is no guarantee that they
 588                            will be correct.  */
 589   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 590                            the loop will exit in the first iteration (i.e.
 591                            its latch will not be executed), even if the niter
 592                            field says otherwise.  */
 593   tree niter;           /* The expression giving the number of iterations of
 594                            a loop (provided that assumptions == true and
 595                            may_be_zero == false), more precisely the number
 596                            of executions of the latch of the loop.  */
 597   double_int max;       /* The upper bound on the number of iterations of
 598                            the loop.  */
 599
 600   /* The simplified shape of the exit condition.  The loop exits if
 601      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 602      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 603      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 604      by loop unrolling.  */
 605   affine_iv control;
 606   tree bound;
 607   enum tree_code cmp;
 608 };
 609
 610 /* In tree-ssa-phiopt.c */
 611 bool empty_block_p (basic_block);
 612 basic_block *blocks_in_phiopt_order (void);
 613 bool nonfreeing_call_p (gimple);
 614
 615 /* In tree-ssa-loop*.c  */
 616
 617 unsigned int tree_ssa_lim (void);
 618 unsigned int tree_ssa_unswitch_loops (void);
 619 unsigned int canonicalize_induction_variables (void);
 620 unsigned int tree_unroll_loops_completely (bool, bool);
 621 unsigned int tree_ssa_prefetch_arrays (void);
 622 void tree_ssa_iv_optimize (void);
 623 unsigned tree_predictive_commoning (void);
 624 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 625 bool parallelize_loops (void);
 626
 627 bool loop_only_exit_p (const struct loop *, const_edge);
 628 bool number_of_iterations_exit (struct loop *, edge,
 629                                 struct tree_niter_desc *niter, bool,
 630                                 bool every_iteration = true);
 631 tree find_loop_niter (struct loop *, edge *);
 632 tree loop_niter_by_eval (struct loop *, edge);
 633 tree find_loop_niter_by_eval (struct loop *, edge *);
 634 void estimate_numbers_of_iterations (void);
 635 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 636 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 637
 638 bool nowrap_type_p (tree);
 639 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 640 enum ev_direction scev_direction (const_tree);
 641
 642 void free_numbers_of_iterations_estimates (void);
 643 void free_numbers_of_iterations_estimates_loop (struct loop *);
 644 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 645 void verify_loop_closed_ssa (bool);
 646 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 647 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 648                 tree *, tree *);
 649 basic_block split_loop_exit_edge (edge);
 650 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 651                                      bool *);
 652 basic_block ip_end_pos (struct loop *);
 653 basic_block ip_normal_pos (struct loop *);
 654 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 655                                          unsigned int, sbitmap,
 656                                          edge, vec<edge> *,
 657                                          int);
 658 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 659 tree expand_simple_operations (tree);
 660 void substitute_in_loop_info (struct loop *, tree, tree);
 661 edge single_dom_exit (struct loop *);
 662 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 663                         struct tree_niter_desc *niter);
 664 void tree_unroll_loop (struct loop *, unsigned,
 665                        edge, struct tree_niter_desc *);
 666 typedef void (*transform_callback)(struct loop *, void *);
 667 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 668                                      edge, struct tree_niter_desc *,
 669                                      transform_callback, void *);
 670 bool contains_abnormal_ssa_name_p (tree);
 671 bool stmt_dominates_stmt_p (gimple, gimple);
 672
 673 /* In tree-ssa-dce.c */
 674 void mark_virtual_operand_for_renaming (tree);
 675 void mark_virtual_phi_result_for_renaming (gimple);
 676
 677 /* In tree-ssa-threadedge.c */
 678 extern void threadedge_initialize_values (void);
 679 extern void threadedge_finalize_values (void);
 680 extern vec<tree> ssa_name_values;
 681 #define SSA_NAME_VALUE(x) \
 682     (SSA_NAME_VERSION(x) < ssa_name_values.length () \
 683      ? ssa_name_values[SSA_NAME_VERSION(x)] \
 684      : NULL_TREE)
 685 extern void set_ssa_name_value (tree, tree);
 686 extern bool potentially_threadable_block (basic_block);
 687 extern void thread_across_edge (gimple, edge, bool,
 688                                 vec<tree> *, tree (*) (gimple, gimple));
 689 extern void propagate_threaded_block_debug_into (basic_block, basic_block);
 690
 691 /* In tree-ssa-loop-im.c  */
 692 /* The possibilities of statement movement.  */
 693
 694 enum move_pos
 695   {
 696     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 697     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 698                                    become executed -- memory accesses, ... */
 699     MOVE_POSSIBLE               /* Unlimited movement.  */
 700   };
 701 extern enum move_pos movement_possibility (gimple);
 702 char *get_lsm_tmp_name (tree, unsigned);
 703
 704 /* In tree-flow-inline.h  */
 705 static inline bool unmodifiable_var_p (const_tree);
 706 static inline bool ref_contains_array_ref (const_tree);
 707
 708 /* In tree-eh.c  */
 709 extern void make_eh_edges (gimple);
 710 extern bool make_eh_dispatch_edges (gimple);
 711 extern edge redirect_eh_edge (edge, basic_block);
 712 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 713 extern bool stmt_could_throw_p (gimple);
 714 extern bool stmt_can_throw_internal (gimple);
 715 extern bool stmt_can_throw_external (gimple);
 716 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 717 extern void add_stmt_to_eh_lp (gimple, int);
 718 extern bool remove_stmt_from_eh_lp (gimple);
 719 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 720 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 721 extern int lookup_stmt_eh_lp (gimple);
 722 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 723 extern bool maybe_clean_eh_stmt (gimple);
 724 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 725 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 726                                         struct function *, gimple,
 727                                         struct pointer_map_t *, int);
 728 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 729 extern bool verify_eh_edges (gimple);
 730 extern bool verify_eh_dispatch_edge (gimple);
 731 extern void maybe_remove_unreachable_handlers (void);
 732
 733 /* In tree-ssa-pre.c  */
 734 void debug_value_expressions (unsigned int);
 735
 736 /* In tree-loop-linear.c  */
 737 extern void linear_transform_loops (void);
 738 extern unsigned perfect_loop_nest_depth (struct loop *);
 739
 740 /* In graphite.c  */
 741 extern void graphite_transform_loops (void);
 742
 743 /* In tree-data-ref.c  */
 744 extern void tree_check_data_deps (void);
 745
 746 /* In tree-ssa-loop-ivopts.c  */
 747 bool expr_invariant_in_loop_p (struct loop *, tree);
 748 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 749 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 750                                       addr_space_t);
 751 bool may_be_nonaddressable_p (tree expr);
 752
 753 /* In tree-ssa-threadupdate.c.  */
 754 extern bool thread_through_all_blocks (bool);
 755 extern void register_jump_thread (edge, edge, edge);
 756
 757 /* In gimplify.c  */
 758 tree force_gimple_operand_1 (tree, gimple_seq *, gimple_predicate, tree);
 759 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 760 tree force_gimple_operand_gsi_1 (gimple_stmt_iterator *, tree,
 761                                  gimple_predicate, tree,
 762                                  bool, enum gsi_iterator_update);
 763 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 764                                bool, enum gsi_iterator_update);
 765 tree gimple_fold_indirect_ref (tree);
 766
 767 /* In tree-ssa-live.c */
 768 extern void remove_unused_locals (void);
 769 extern void dump_scope_blocks (FILE *, int);
 770 extern void debug_scope_blocks (int);
 771 extern void debug_scope_block (tree, int);
 772
 773 /* In tree-ssa-address.c  */
 774
 775 /* Description of a memory address.  */
 776
 777 struct mem_address
 778 {
 779   tree symbol, base, index, step, offset;
 780 };
 781
 782 struct affine_tree_combination;
 783 tree create_mem_ref (gimple_stmt_iterator *, tree,
 784                      struct affine_tree_combination *, tree, tree, tree, bool);
 785 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 786 void get_address_description (tree, struct mem_address *);
 787 tree maybe_fold_tmr (tree);
 788
 789 unsigned int execute_fixup_cfg (void);
 790 bool fixup_noreturn_call (gimple stmt);
 791
 792 /* In ipa-pure-const.c  */
 793 void warn_function_noreturn (tree);
 794
 795 /* In tree-ssa-ter.c  */
 796 bool stmt_is_replaceable_p (gimple);
 797
 798 /* In tree-parloops.c  */
 799 bool parallelized_function_p (tree);
 800
 801 #include "tree-flow-inline.h"
 802
 803 void swap_tree_operands (gimple, tree *, tree *);
 804
 805 #endif /* _TREE_FLOW_H  */