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 #define num_ssa_names (vec_safe_length (cfun->gimple_df->ssa_names))
 286 #define ssa_name(i) ((*cfun->gimple_df->ssa_names)[(i)])
 287
 288 /* Macros for showing usage statistics.  */
 289 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 290                   ? (x)                                 \
 291                   : ((x) < 1024*1024*10                 \
 292                      ? (x) / 1024                       \
 293                      : (x) / (1024*1024))))
 294
 295 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 296
 297 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 298
 299 /*---------------------------------------------------------------------------
 300                               OpenMP Region Tree
 301 ---------------------------------------------------------------------------*/
 302
 303 /* Parallel region information.  Every parallel and workshare
 304    directive is enclosed between two markers, the OMP_* directive
 305    and a corresponding OMP_RETURN statement.  */
 306
 307 struct omp_region
 308 {
 309   /* The enclosing region.  */
 310   struct omp_region *outer;
 311
 312   /* First child region.  */
 313   struct omp_region *inner;
 314
 315   /* Next peer region.  */
 316   struct omp_region *next;
 317
 318   /* Block containing the omp directive as its last stmt.  */
 319   basic_block entry;
 320
 321   /* Block containing the OMP_RETURN as its last stmt.  */
 322   basic_block exit;
 323
 324   /* Block containing the OMP_CONTINUE as its last stmt.  */
 325   basic_block cont;
 326
 327   /* If this is a combined parallel+workshare region, this is a list
 328      of additional arguments needed by the combined parallel+workshare
 329      library call.  */
 330   vec<tree, va_gc> *ws_args;
 331
 332   /* The code for the omp directive of this region.  */
 333   enum gimple_code type;
 334
 335   /* Schedule kind, only used for OMP_FOR type regions.  */
 336   enum omp_clause_schedule_kind sched_kind;
 337
 338   /* True if this is a combined parallel+workshare region.  */
 339   bool is_combined_parallel;
 340 };
 341
 342 extern struct omp_region *root_omp_region;
 343 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 344                                           struct omp_region *);
 345 extern void free_omp_regions (void);
 346 void omp_expand_local (basic_block);
 347 extern tree find_omp_clause (tree, enum omp_clause_code);
 348 tree copy_var_decl (tree, tree, tree);
 349
 350 /*---------------------------------------------------------------------------
 351                               Function prototypes
 352 ---------------------------------------------------------------------------*/
 353 /* In tree-cfg.c  */
 354
 355 /* Location to track pending stmt for edge insertion.  */
 356 #define PENDING_STMT(e) ((e)->insns.g)
 357
 358 extern void delete_tree_cfg_annotations (void);
 359 extern bool stmt_ends_bb_p (gimple);
 360 extern bool is_ctrl_stmt (gimple);
 361 extern bool is_ctrl_altering_stmt (gimple);
 362 extern bool simple_goto_p (gimple);
 363 extern bool stmt_can_make_abnormal_goto (gimple);
 364 extern basic_block single_noncomplex_succ (basic_block bb);
 365 extern void gimple_dump_bb (FILE *, basic_block, int, int);
 366 extern void gimple_debug_bb (basic_block);
 367 extern basic_block gimple_debug_bb_n (int);
 368 extern void gimple_dump_cfg (FILE *, int);
 369 extern void gimple_debug_cfg (int);
 370 extern void dump_cfg_stats (FILE *);
 371 extern void dot_cfg (void);
 372 extern void debug_cfg_stats (void);
 373 extern void debug_loops (int);
 374 extern void debug_loop (struct loop *, int);
 375 extern void debug (struct loop &ref);
 376 extern void debug (struct loop *ptr);
 377 extern void debug_verbose (struct loop &ref);
 378 extern void debug_verbose (struct loop *ptr);
 379 extern void debug_loop_num (unsigned, int);
 380 extern void print_loops (FILE *, int);
 381 extern void print_loops_bb (FILE *, basic_block, int, int);
 382 extern void cleanup_dead_labels (void);
 383 extern void group_case_labels_stmt (gimple);
 384 extern void group_case_labels (void);
 385 extern gimple first_stmt (basic_block);
 386 extern gimple last_stmt (basic_block);
 387 extern gimple last_and_only_stmt (basic_block);
 388 extern edge find_taken_edge (basic_block, tree);
 389 extern basic_block label_to_block_fn (struct function *, tree);
 390 #define label_to_block(t) (label_to_block_fn (cfun, t))
 391 extern void notice_special_calls (gimple);
 392 extern void clear_special_calls (void);
 393 extern void verify_gimple_in_seq (gimple_seq);
 394 extern void verify_gimple_in_cfg (struct function *);
 395 extern tree gimple_block_label (basic_block);
 396 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 397 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 398                                         basic_block *, bool);
 399 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 400                                       basic_block *);
 401 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 402                                           vec<basic_block> *bbs_p);
 403 extern void add_phi_args_after_copy_bb (basic_block);
 404 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 405 extern bool gimple_purge_dead_eh_edges (basic_block);
 406 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 407 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 408 extern bool gimple_purge_all_dead_abnormal_call_edges (const_bitmap);
 409 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 410                              tree, tree);
 411 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 412                              tree, tree, tree);
 413 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 414                              tree, tree, tree, tree);
 415 extern void init_empty_tree_cfg (void);
 416 extern void init_empty_tree_cfg_for_function (struct function *);
 417 extern void fold_cond_expr_cond (void);
 418 extern void make_abnormal_goto_edges (basic_block, bool);
 419 extern void replace_uses_by (tree, tree);
 420 extern void start_recording_case_labels (void);
 421 extern void end_recording_case_labels (void);
 422 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 423                                            basic_block, tree);
 424 void remove_edge_and_dominated_blocks (edge);
 425 bool tree_node_can_be_shared (tree);
 426
 427 /* In tree-cfgcleanup.c  */
 428 extern bitmap cfgcleanup_altered_bbs;
 429 extern bool cleanup_tree_cfg (void);
 430
 431 /* In tree-pretty-print.c.  */
 432 extern void dump_generic_bb (FILE *, basic_block, int, int);
 433 extern int op_code_prio (enum tree_code);
 434 extern int op_prio (const_tree);
 435 extern const char *op_symbol_code (enum tree_code);
 436
 437 /* In tree-dfa.c  */
 438 extern void renumber_gimple_stmt_uids (void);
 439 extern void renumber_gimple_stmt_uids_in_blocks (basic_block *, int);
 440 extern void dump_dfa_stats (FILE *);
 441 extern void debug_dfa_stats (void);
 442 extern void dump_variable (FILE *, tree);
 443 extern void debug_variable (tree);
 444 extern void set_ssa_default_def (struct function *, tree, tree);
 445 extern tree ssa_default_def (struct function *, tree);
 446 extern tree get_or_create_ssa_default_def (struct function *, tree);
 447 extern bool stmt_references_abnormal_ssa_name (gimple);
 448 extern tree get_addr_base_and_unit_offset (tree, HOST_WIDE_INT *);
 449 extern void dump_enumerated_decls (FILE *, int);
 450
 451 /* In tree-phinodes.c  */
 452 extern void reserve_phi_args_for_new_edge (basic_block);
 453 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 454 extern gimple create_phi_node (tree, basic_block);
 455 extern void add_phi_arg (gimple, tree, edge, source_location);
 456 extern void remove_phi_args (edge);
 457 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 458 extern void remove_phi_nodes (basic_block);
 459 extern void release_phi_node (gimple);
 460 extern void phinodes_print_statistics (void);
 461
 462 /* In gimple-low.c  */
 463 extern void record_vars_into (tree, tree);
 464 extern void record_vars (tree);
 465 extern bool gimple_seq_may_fallthru (gimple_seq);
 466 extern bool gimple_stmt_may_fallthru (gimple);
 467 extern bool gimple_check_call_matching_types (gimple, tree, bool);
 468
 469
 470 /* In tree-ssa.c  */
 471
 472 /* Mapping for redirected edges.  */
 473 struct _edge_var_map {
 474   tree result;                  /* PHI result.  */
 475   tree def;                     /* PHI arg definition.  */
 476   source_location locus;        /* PHI arg location.  */
 477 };
 478 typedef struct _edge_var_map edge_var_map;
 479
 480
 481 /* A vector of var maps.  */
 482 typedef vec<edge_var_map, va_heap, vl_embed> edge_var_map_vector;
 483
 484 extern void init_tree_ssa (struct function *);
 485 extern void redirect_edge_var_map_add (edge, tree, tree, source_location);
 486 extern void redirect_edge_var_map_clear (edge);
 487 extern void redirect_edge_var_map_dup (edge, edge);
 488 extern edge_var_map_vector *redirect_edge_var_map_vector (edge);
 489 extern void redirect_edge_var_map_destroy (void);
 490
 491 extern edge ssa_redirect_edge (edge, basic_block);
 492 extern void flush_pending_stmts (edge);
 493 extern void verify_ssa (bool);
 494 extern void delete_tree_ssa (void);
 495 extern bool ssa_undefined_value_p (tree);
 496 extern void warn_uninit (enum opt_code, tree, tree, tree, const char *, void *);
 497 extern unsigned int warn_uninitialized_vars (bool);
 498 extern void execute_update_addresses_taken (void);
 499
 500 /* Call-back function for walk_use_def_chains().  At each reaching
 501    definition, a function with this prototype is called.  */
 502 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *);
 503
 504 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 505
 506 void insert_debug_temps_for_defs (gimple_stmt_iterator *);
 507 void insert_debug_temp_for_var_def (gimple_stmt_iterator *, tree);
 508 void reset_debug_uses (gimple);
 509 void release_defs_bitset (bitmap toremove);
 510
 511 /* In tree-into-ssa.c  */
 512 void update_ssa (unsigned);
 513 void delete_update_ssa (void);
 514 tree create_new_def_for (tree, gimple, def_operand_p);
 515 bool need_ssa_update_p (struct function *);
 516 bool name_registered_for_update_p (tree);
 517 void release_ssa_name_after_update_ssa (tree);
 518 void mark_virtual_operands_for_renaming (struct function *);
 519 tree get_current_def (tree);
 520 void set_current_def (tree, tree);
 521
 522 /* In tree-ssanames.c  */
 523 extern void init_ssanames (struct function *, int);
 524 extern void fini_ssanames (void);
 525 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 526 extern tree copy_ssa_name_fn (struct function *, tree, gimple);
 527 extern tree duplicate_ssa_name_fn (struct function *, tree, gimple);
 528 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 529 extern void release_ssa_name (tree);
 530 extern void release_defs (gimple);
 531 extern void replace_ssa_name_symbol (tree, tree);
 532 extern bool get_ptr_info_alignment (struct ptr_info_def *, unsigned int *,
 533                                     unsigned int *);
 534 extern void mark_ptr_info_alignment_unknown (struct ptr_info_def *);
 535 extern void set_ptr_info_alignment (struct ptr_info_def *, unsigned int,
 536                                     unsigned int);
 537 extern void adjust_ptr_info_misalignment (struct ptr_info_def *,
 538                                           unsigned int);
 539
 540 extern void ssanames_print_statistics (void);
 541
 542 /* In tree-ssa-ccp.c  */
 543 tree fold_const_aggregate_ref (tree);
 544 tree gimple_fold_stmt_to_constant (gimple, tree (*)(tree));
 545
 546 /* In tree-ssa-dom.c  */
 547 extern void dump_dominator_optimization_stats (FILE *);
 548 extern void debug_dominator_optimization_stats (void);
 549 int loop_depth_of_name (tree);
 550 tree degenerate_phi_result (gimple);
 551 bool simple_iv_increment_p (gimple);
 552
 553 /* In tree-ssa-copy.c  */
 554 extern void propagate_value (use_operand_p, tree);
 555 extern void propagate_tree_value (tree *, tree);
 556 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 557 extern void replace_exp (use_operand_p, tree);
 558 extern bool may_propagate_copy (tree, tree);
 559 extern bool may_propagate_copy_into_stmt (gimple, tree);
 560 extern bool may_propagate_copy_into_asm (tree);
 561
 562 /* In tree-ssa-loop-ch.c  */
 563 bool do_while_loop_p (struct loop *);
 564
 565 /* Affine iv.  */
 566
 567 typedef struct
 568 {
 569   /* Iv = BASE + STEP * i.  */
 570   tree base, step;
 571
 572   /* True if this iv does not overflow.  */
 573   bool no_overflow;
 574 } affine_iv;
 575
 576 /* Description of number of iterations of a loop.  All the expressions inside
 577    the structure can be evaluated at the end of the loop's preheader
 578    (and due to ssa form, also anywhere inside the body of the loop).  */
 579
 580 struct tree_niter_desc
 581 {
 582   tree assumptions;     /* The boolean expression.  If this expression evaluates
 583                            to false, then the other fields in this structure
 584                            should not be used; there is no guarantee that they
 585                            will be correct.  */
 586   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 587                            the loop will exit in the first iteration (i.e.
 588                            its latch will not be executed), even if the niter
 589                            field says otherwise.  */
 590   tree niter;           /* The expression giving the number of iterations of
 591                            a loop (provided that assumptions == true and
 592                            may_be_zero == false), more precisely the number
 593                            of executions of the latch of the loop.  */
 594   double_int max;       /* The upper bound on the number of iterations of
 595                            the loop.  */
 596
 597   /* The simplified shape of the exit condition.  The loop exits if
 598      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 599      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 600      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 601      by loop unrolling.  */
 602   affine_iv control;
 603   tree bound;
 604   enum tree_code cmp;
 605 };
 606
 607 /* In tree-ssa-phiopt.c */
 608 bool empty_block_p (basic_block);
 609 basic_block *blocks_in_phiopt_order (void);
 610 bool nonfreeing_call_p (gimple);
 611
 612 /* In tree-ssa-loop*.c  */
 613
 614 unsigned int tree_ssa_lim (void);
 615 unsigned int tree_ssa_unswitch_loops (void);
 616 unsigned int canonicalize_induction_variables (void);
 617 unsigned int tree_unroll_loops_completely (bool, bool);
 618 unsigned int tree_ssa_prefetch_arrays (void);
 619 void tree_ssa_iv_optimize (void);
 620 unsigned tree_predictive_commoning (void);
 621 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 622 bool parallelize_loops (void);
 623
 624 bool loop_only_exit_p (const struct loop *, const_edge);
 625 bool number_of_iterations_exit (struct loop *, edge,
 626                                 struct tree_niter_desc *niter, bool,
 627                                 bool every_iteration = true);
 628 tree find_loop_niter (struct loop *, edge *);
 629 tree loop_niter_by_eval (struct loop *, edge);
 630 tree find_loop_niter_by_eval (struct loop *, edge *);
 631 void estimate_numbers_of_iterations (void);
 632 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 633 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 634
 635 bool nowrap_type_p (tree);
 636 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 637 enum ev_direction scev_direction (const_tree);
 638
 639 void free_numbers_of_iterations_estimates (void);
 640 void free_numbers_of_iterations_estimates_loop (struct loop *);
 641 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 642 void verify_loop_closed_ssa (bool);
 643 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 644 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 645                 tree *, tree *);
 646 basic_block split_loop_exit_edge (edge);
 647 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 648                                      bool *);
 649 basic_block ip_end_pos (struct loop *);
 650 basic_block ip_normal_pos (struct loop *);
 651 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 652                                          unsigned int, sbitmap,
 653                                          edge, vec<edge> *,
 654                                          int);
 655 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 656 tree expand_simple_operations (tree);
 657 void substitute_in_loop_info (struct loop *, tree, tree);
 658 edge single_dom_exit (struct loop *);
 659 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 660                         struct tree_niter_desc *niter);
 661 void tree_unroll_loop (struct loop *, unsigned,
 662                        edge, struct tree_niter_desc *);
 663 typedef void (*transform_callback)(struct loop *, void *);
 664 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 665                                      edge, struct tree_niter_desc *,
 666                                      transform_callback, void *);
 667 bool contains_abnormal_ssa_name_p (tree);
 668 bool stmt_dominates_stmt_p (gimple, gimple);
 669
 670 /* In tree-ssa-dce.c */
 671 void mark_virtual_operand_for_renaming (tree);
 672 void mark_virtual_phi_result_for_renaming (gimple);
 673
 674 /* In tree-ssa-threadedge.c */
 675 extern void threadedge_initialize_values (void);
 676 extern void threadedge_finalize_values (void);
 677 extern vec<tree> ssa_name_values;
 678 #define SSA_NAME_VALUE(x) \
 679     (SSA_NAME_VERSION(x) < ssa_name_values.length () \
 680      ? ssa_name_values[SSA_NAME_VERSION(x)] \
 681      : NULL_TREE)
 682 extern void set_ssa_name_value (tree, tree);
 683 extern bool potentially_threadable_block (basic_block);
 684 extern void thread_across_edge (gimple, edge, bool,
 685                                 vec<tree> *, tree (*) (gimple, gimple));
 686 extern void propagate_threaded_block_debug_into (basic_block, basic_block);
 687
 688 /* In tree-ssa-loop-im.c  */
 689 /* The possibilities of statement movement.  */
 690
 691 enum move_pos
 692   {
 693     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 694     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 695                                    become executed -- memory accesses, ... */
 696     MOVE_POSSIBLE               /* Unlimited movement.  */
 697   };
 698 extern enum move_pos movement_possibility (gimple);
 699 char *get_lsm_tmp_name (tree, unsigned);
 700
 701 /* In tree-flow-inline.h  */
 702 static inline bool unmodifiable_var_p (const_tree);
 703 static inline bool ref_contains_array_ref (const_tree);
 704
 705 /* In tree-eh.c  */
 706 extern void make_eh_edges (gimple);
 707 extern bool make_eh_dispatch_edges (gimple);
 708 extern edge redirect_eh_edge (edge, basic_block);
 709 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 710 extern bool stmt_could_throw_p (gimple);
 711 extern bool stmt_can_throw_internal (gimple);
 712 extern bool stmt_can_throw_external (gimple);
 713 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 714 extern void add_stmt_to_eh_lp (gimple, int);
 715 extern bool remove_stmt_from_eh_lp (gimple);
 716 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 717 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 718 extern int lookup_stmt_eh_lp (gimple);
 719 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 720 extern bool maybe_clean_eh_stmt (gimple);
 721 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 722 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 723                                         struct function *, gimple,
 724                                         struct pointer_map_t *, int);
 725 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 726 extern bool verify_eh_edges (gimple);
 727 extern bool verify_eh_dispatch_edge (gimple);
 728 extern void maybe_remove_unreachable_handlers (void);
 729
 730 /* In tree-ssa-pre.c  */
 731 void debug_value_expressions (unsigned int);
 732
 733 /* In tree-loop-linear.c  */
 734 extern void linear_transform_loops (void);
 735 extern unsigned perfect_loop_nest_depth (struct loop *);
 736
 737 /* In graphite.c  */
 738 extern void graphite_transform_loops (void);
 739
 740 /* In tree-data-ref.c  */
 741 extern void tree_check_data_deps (void);
 742
 743 /* In tree-ssa-loop-ivopts.c  */
 744 bool expr_invariant_in_loop_p (struct loop *, tree);
 745 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 746 struct loop *outermost_invariant_loop_for_expr (struct loop *, tree);
 747 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 748                                       addr_space_t);
 749 bool may_be_nonaddressable_p (tree expr);
 750
 751 /* In tree-ssa-threadupdate.c.  */
 752 extern bool thread_through_all_blocks (bool);
 753 extern void register_jump_thread (edge, edge, edge);
 754
 755 /* In gimplify.c  */
 756 tree force_gimple_operand_1 (tree, gimple_seq *, gimple_predicate, tree);
 757 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 758 tree force_gimple_operand_gsi_1 (gimple_stmt_iterator *, tree,
 759                                  gimple_predicate, tree,
 760                                  bool, enum gsi_iterator_update);
 761 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 762                                bool, enum gsi_iterator_update);
 763 tree gimple_fold_indirect_ref (tree);
 764
 765 /* In tree-ssa-live.c */
 766 extern void remove_unused_locals (void);
 767 extern void dump_scope_blocks (FILE *, int);
 768 extern void debug_scope_blocks (int);
 769 extern void debug_scope_block (tree, int);
 770
 771 /* In tree-ssa-address.c  */
 772
 773 /* Description of a memory address.  */
 774
 775 struct mem_address
 776 {
 777   tree symbol, base, index, step, offset;
 778 };
 779
 780 struct affine_tree_combination;
 781 tree create_mem_ref (gimple_stmt_iterator *, tree,
 782                      struct affine_tree_combination *, tree, tree, tree, bool);
 783 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 784 void get_address_description (tree, struct mem_address *);
 785 tree maybe_fold_tmr (tree);
 786
 787 unsigned int execute_fixup_cfg (void);
 788 bool fixup_noreturn_call (gimple stmt);
 789
 790 /* In ipa-pure-const.c  */
 791 void warn_function_noreturn (tree);
 792
 793 /* In tree-ssa-ter.c  */
 794 bool stmt_is_replaceable_p (gimple);
 795
 796 /* In tree-parloops.c  */
 797 bool parallelized_function_p (tree);
 798
 799 #include "tree-flow-inline.h"
 800
 801 void swap_tree_operands (gimple, tree *, tree *);
 802
 803 #endif /* _TREE_FLOW_H  */