gcc/tree-flow.h

   1 /* Data and Control Flow Analysis for Trees.
   2    Copyright (C) 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
   3    Free Software Foundation, Inc.
   4    Contributed by Diego Novillo <dnovillo@redhat.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 3, or (at your option)
  11 any later version.
  12
  13 GCC is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #ifndef _TREE_FLOW_H
  23 #define _TREE_FLOW_H 1
  24
  25 #include "bitmap.h"
  26 #include "sbitmap.h"
  27 #include "basic-block.h"
  28 #include "hashtab.h"
  29 #include "gimple.h"
  30 #include "tree-ssa-operands.h"
  31 #include "cgraph.h"
  32 #include "ipa-reference.h"
  33 #include "tree-ssa-alias.h"
  34
  35
  36 /* This structure is used to map a gimple statement to a label,
  37    or list of labels to represent transaction restart.  */
  38
  39 struct GTY(()) tm_restart_node {
  40   gimple stmt;
  41   tree label_or_list;
  42 };
  43
  44 /* Gimple dataflow datastructure. All publicly available fields shall have
  45    gimple_ accessor defined in tree-flow-inline.h, all publicly modifiable
  46    fields should have gimple_set accessor.  */
  47 struct GTY(()) gimple_df {
  48   /* A vector of all the noreturn calls passed to modify_stmt.
  49      cleanup_control_flow uses it to detect cases where a mid-block
  50      indirect call has been turned into a noreturn call.  When this
  51      happens, all the instructions after the call are no longer
  52      reachable and must be deleted as dead.  */
  53   VEC(gimple,gc) *modified_noreturn_calls;
  54
  55   /* Array of all SSA_NAMEs used in the function.  */
  56   VEC(tree,gc) *ssa_names;
  57
  58   /* Artificial variable used for the virtual operand FUD chain.  */
  59   tree vop;
  60
  61   /* The PTA solution for the ESCAPED artificial variable.  */
  62   struct pt_solution escaped;
  63
  64   /* A map of decls to artificial ssa-names that point to the partition
  65      of the decl.  */
  66   struct pointer_map_t * GTY((skip(""))) decls_to_pointers;
  67
  68   /* Free list of SSA_NAMEs.  */
  69   VEC(tree,gc) *free_ssanames;
  70
  71   /* Hashtable holding definition for symbol.  If this field is not NULL, it
  72      means that the first reference to this variable in the function is a
  73      USE or a VUSE.  In those cases, the SSA renamer creates an SSA name
  74      for this variable with an empty defining statement.  */
  75   htab_t GTY((param_is (union tree_node))) default_defs;
  76
  77   /* True if there are any symbols that need to be renamed.  */
  78   unsigned int ssa_renaming_needed : 1;
  79
  80   /* True if all virtual operands need to be renamed.  */
  81   unsigned int rename_vops : 1;
  82
  83   /* True if the code is in ssa form.  */
  84   unsigned int in_ssa_p : 1;
  85
  86   /* True if IPA points-to information was computed for this function.  */
  87   unsigned int ipa_pta : 1;
  88
  89   struct ssa_operands ssa_operands;
  90
  91   /* Map gimple stmt to tree label (or list of labels) for transaction
  92      restart and abort.  */
  93   htab_t GTY ((param_is (struct tm_restart_node))) tm_restart;
  94 };
  95
  96 /* Accessors for internal use only.  Generic code should use abstraction
  97    provided by tree-flow-inline.h or specific modules.  */
  98 #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames
  99 #define SSANAMES(fun) (fun)->gimple_df->ssa_names
 100 #define MODIFIED_NORETURN_CALLS(fun) (fun)->gimple_df->modified_noreturn_calls
 101 #define DEFAULT_DEFS(fun) (fun)->gimple_df->default_defs
 102
 103 typedef struct
 104 {
 105   htab_t htab;
 106   PTR *slot;
 107   PTR *limit;
 108 } htab_iterator;
 109
 110 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
 111    storing each element in RESULT, which is of type TYPE.  */
 112 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
 113   for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
 114         !end_htab_p (&(ITER)); \
 115         RESULT = (TYPE) next_htab_element (&(ITER)))
 116
 117 /*---------------------------------------------------------------------------
 118                       Attributes for SSA_NAMEs.
 119
 120   NOTE: These structures are stored in struct tree_ssa_name
 121   but are only used by the tree optimizers, so it makes better sense
 122   to declare them here to avoid recompiling unrelated files when
 123   making changes.
 124 ---------------------------------------------------------------------------*/
 125
 126 /* Aliasing information for SSA_NAMEs representing pointer variables.  */
 127
 128 struct GTY(()) ptr_info_def
 129 {
 130   /* The points-to solution.  */
 131   struct pt_solution pt;
 132
 133   /* Alignment and misalignment of the pointer in bytes.  Together
 134      align and misalign specify low known bits of the pointer.
 135      ptr & (align - 1) == misalign.  */
 136
 137   /* When known, this is the power-of-two byte alignment of the object this
 138      pointer points into.  This is usually DECL_ALIGN_UNIT for decls and
 139      MALLOC_ABI_ALIGNMENT for allocated storage.  When the alignment is not
 140      known, it is zero.  Do not access directly but use functions
 141      get_ptr_info_alignment, set_ptr_info_alignment,
 142      mark_ptr_info_alignment_unknown and similar.  */
 143   unsigned int align;
 144
 145   /* When alignment is known, the byte offset this pointer differs from the
 146      above alignment.  Access only through the same helper functions as align
 147      above.  */
 148   unsigned int misalign;
 149 };
 150
 151
 152 /* It is advantageous to avoid things like life analysis for variables which
 153    do not need PHI nodes.  This enum describes whether or not a particular
 154    variable may need a PHI node.  */
 155
 156 enum need_phi_state {
 157   /* This is the default.  If we are still in this state after finding
 158      all the definition and use sites, then we will assume the variable
 159      needs PHI nodes.  This is probably an overly conservative assumption.  */
 160   NEED_PHI_STATE_UNKNOWN,
 161
 162   /* This state indicates that we have seen one or more sets of the
 163      variable in a single basic block and that the sets dominate all
 164      uses seen so far.  If after finding all definition and use sites
 165      we are still in this state, then the variable does not need any
 166      PHI nodes.  */
 167   NEED_PHI_STATE_NO,
 168
 169   /* This state indicates that we have either seen multiple definitions of
 170      the variable in multiple blocks, or that we encountered a use in a
 171      block that was not dominated by the block containing the set(s) of
 172      this variable.  This variable is assumed to need PHI nodes.  */
 173   NEED_PHI_STATE_MAYBE
 174 };
 175
 176
 177 /* Immediate use lists are used to directly access all uses for an SSA
 178    name and get pointers to the statement for each use.
 179
 180    The structure ssa_use_operand_d consists of PREV and NEXT pointers
 181    to maintain the list.  A USE pointer, which points to address where
 182    the use is located and a LOC pointer which can point to the
 183    statement where the use is located, or, in the case of the root
 184    node, it points to the SSA name itself.
 185
 186    The list is anchored by an occurrence of ssa_operand_d *in* the
 187    ssa_name node itself (named 'imm_uses').  This node is uniquely
 188    identified by having a NULL USE pointer. and the LOC pointer
 189    pointing back to the ssa_name node itself.  This node forms the
 190    base for a circular list, and initially this is the only node in
 191    the list.
 192
 193    Fast iteration allows each use to be examined, but does not allow
 194    any modifications to the uses or stmts.
 195
 196    Normal iteration allows insertion, deletion, and modification. the
 197    iterator manages this by inserting a marker node into the list
 198    immediately before the node currently being examined in the list.
 199    this marker node is uniquely identified by having null stmt *and* a
 200    null use pointer.
 201
 202    When iterating to the next use, the iteration routines check to see
 203    if the node after the marker has changed. if it has, then the node
 204    following the marker is now the next one to be visited. if not, the
 205    marker node is moved past that node in the list (visualize it as
 206    bumping the marker node through the list).  this continues until
 207    the marker node is moved to the original anchor position. the
 208    marker node is then removed from the list.
 209
 210    If iteration is halted early, the marker node must be removed from
 211    the list before continuing.  */
 212 typedef struct immediate_use_iterator_d
 213 {
 214   /* This is the current use the iterator is processing.  */
 215   ssa_use_operand_t *imm_use;
 216   /* This marks the last use in the list (use node from SSA_NAME)  */
 217   ssa_use_operand_t *end_p;
 218   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 219   ssa_use_operand_t iter_node;
 220   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 221      the next one is traversed to, so it must be cached early.  */
 222   ssa_use_operand_t *next_imm_name;
 223 } imm_use_iterator;
 224
 225
 226 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 227    modifying stmts will cause this iterator to malfunction.  */
 228
 229 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)               \
 230   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 231        !end_readonly_imm_use_p (&(ITER));                       \
 232        (void) ((DEST) = next_readonly_imm_use (&(ITER))))
 233
 234 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 235
 236 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 237   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 238        !end_imm_use_stmt_p (&(ITER));                           \
 239        (void) ((STMT) = next_imm_use_stmt (&(ITER))))
 240
 241 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 242    do so will result in leaving a iterator marker node in the immediate
 243    use list, and nothing good will come from that.   */
 244 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 245    {                                                            \
 246      end_imm_use_stmt_traverse (&(ITER));                       \
 247      break;                                                     \
 248    }
 249
 250
 251 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 252    get access to each occurrence of ssavar on the stmt returned by
 253    that iterator..  for instance:
 254
 255      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 256        {
 257          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 258            {
 259              SET_USE (use_p, blah);
 260            }
 261          update_stmt (stmt);
 262        }                                                         */
 263
 264 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 265   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 266        !end_imm_use_on_stmt_p (&(ITER));                        \
 267        (void) ((DEST) = next_imm_use_on_stmt (&(ITER))))
 268
 269
 270
 271 static inline void update_stmt (gimple);
 272 static inline int get_lineno (const_gimple);
 273
 274 /* Accessors for basic block annotations.  */
 275 static inline gimple_seq phi_nodes (const_basic_block);
 276 static inline void set_phi_nodes (basic_block, gimple_seq);
 277
 278 /*---------------------------------------------------------------------------
 279                               Global declarations
 280 ---------------------------------------------------------------------------*/
 281 struct int_tree_map {
 282   unsigned int uid;
 283   tree to;
 284 };
 285
 286 extern unsigned int int_tree_map_hash (const void *);
 287 extern int int_tree_map_eq (const void *, const void *);
 288
 289 extern unsigned int uid_decl_map_hash (const void *);
 290 extern int uid_decl_map_eq (const void *, const void *);
 291
 292 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
 293 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
 294
 295 /* Macros for showing usage statistics.  */
 296 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 297                   ? (x)                                 \
 298                   : ((x) < 1024*1024*10                 \
 299                      ? (x) / 1024                       \
 300                      : (x) / (1024*1024))))
 301
 302 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 303
 304 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 305
 306 /*---------------------------------------------------------------------------
 307                               OpenMP Region Tree
 308 ---------------------------------------------------------------------------*/
 309
 310 /* Parallel region information.  Every parallel and workshare
 311    directive is enclosed between two markers, the OMP_* directive
 312    and a corresponding OMP_RETURN statement.  */
 313
 314 struct omp_region
 315 {
 316   /* The enclosing region.  */
 317   struct omp_region *outer;
 318
 319   /* First child region.  */
 320   struct omp_region *inner;
 321
 322   /* Next peer region.  */
 323   struct omp_region *next;
 324
 325   /* Block containing the omp directive as its last stmt.  */
 326   basic_block entry;
 327
 328   /* Block containing the OMP_RETURN as its last stmt.  */
 329   basic_block exit;
 330
 331   /* Block containing the OMP_CONTINUE as its last stmt.  */
 332   basic_block cont;
 333
 334   /* If this is a combined parallel+workshare region, this is a list
 335      of additional arguments needed by the combined parallel+workshare
 336      library call.  */
 337   VEC(tree,gc) *ws_args;
 338
 339   /* The code for the omp directive of this region.  */
 340   enum gimple_code type;
 341
 342   /* Schedule kind, only used for OMP_FOR type regions.  */
 343   enum omp_clause_schedule_kind sched_kind;
 344
 345   /* True if this is a combined parallel+workshare region.  */
 346   bool is_combined_parallel;
 347 };
 348
 349 extern struct omp_region *root_omp_region;
 350 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 351                                           struct omp_region *);
 352 extern void free_omp_regions (void);
 353 void omp_expand_local (basic_block);
 354 extern tree find_omp_clause (tree, enum omp_clause_code);
 355 tree copy_var_decl (tree, tree, tree);
 356
 357 /*---------------------------------------------------------------------------
 358                               Function prototypes
 359 ---------------------------------------------------------------------------*/
 360 /* In tree-cfg.c  */
 361
 362 /* Location to track pending stmt for edge insertion.  */
 363 #define PENDING_STMT(e) ((e)->insns.g)
 364
 365 extern void delete_tree_cfg_annotations (void);
 366 extern bool stmt_ends_bb_p (gimple);
 367 extern bool is_ctrl_stmt (gimple);
 368 extern bool is_ctrl_altering_stmt (gimple);
 369 extern bool simple_goto_p (gimple);
 370 extern bool stmt_can_make_abnormal_goto (gimple);
 371 extern basic_block single_noncomplex_succ (basic_block bb);
 372 extern void gimple_dump_bb (FILE *, basic_block, int, int);
 373 extern void gimple_debug_bb (basic_block);
 374 extern basic_block gimple_debug_bb_n (int);
 375 extern void gimple_dump_cfg (FILE *, int);
 376 extern void gimple_debug_cfg (int);
 377 extern void dump_cfg_stats (FILE *);
 378 extern void dot_cfg (void);
 379 extern void debug_cfg_stats (void);
 380 extern void debug_loops (int);
 381 extern void debug_loop (struct loop *, int);
 382 extern void debug_loop_num (unsigned, int);
 383 extern void print_loops (FILE *, int);
 384 extern void print_loops_bb (FILE *, basic_block, int, int);
 385 extern void cleanup_dead_labels (void);
 386 extern void group_case_labels_stmt (gimple);
 387 extern void group_case_labels (void);
 388 extern gimple first_stmt (basic_block);
 389 extern gimple last_stmt (basic_block);
 390 extern gimple last_and_only_stmt (basic_block);
 391 extern edge find_taken_edge (basic_block, tree);
 392 extern basic_block label_to_block_fn (struct function *, tree);
 393 #define label_to_block(t) (label_to_block_fn (cfun, t))
 394 extern void notice_special_calls (gimple);
 395 extern void clear_special_calls (void);
 396 extern void verify_gimple_in_seq (gimple_seq);
 397 extern void verify_gimple_in_cfg (struct function *);
 398 extern tree gimple_block_label (basic_block);
 399 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 400 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 401                                         basic_block *);
 402 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 403                                       basic_block *);
 404 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 405                                           VEC(basic_block,heap) **bbs_p);
 406 extern void add_phi_args_after_copy_bb (basic_block);
 407 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 408 extern bool gimple_purge_dead_eh_edges (basic_block);
 409 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 410 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 411 extern bool gimple_purge_all_dead_abnormal_call_edges (const_bitmap);
 412 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 413                              tree, tree);
 414 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 415                              tree, tree, tree);
 416 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 417                              tree, tree, tree, tree);
 418 extern void init_empty_tree_cfg (void);
 419 extern void init_empty_tree_cfg_for_function (struct function *);
 420 extern void fold_cond_expr_cond (void);
 421 extern void make_abnormal_goto_edges (basic_block, bool);
 422 extern void replace_uses_by (tree, tree);
 423 extern void start_recording_case_labels (void);
 424 extern void end_recording_case_labels (void);
 425 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 426                                            basic_block, tree);
 427 void remove_edge_and_dominated_blocks (edge);
 428 bool tree_node_can_be_shared (tree);
 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 tree make_rename_temp (tree, const char *);
 448 extern void set_ssa_default_def (struct function *, tree, tree);
 449 extern tree ssa_default_def (struct function *, tree);
 450 extern tree get_or_create_ssa_default_def (struct function *, tree);
 451 extern bool stmt_references_abnormal_ssa_name (gimple);
 452 extern tree get_addr_base_and_unit_offset (tree, HOST_WIDE_INT *);
 453 extern void dump_enumerated_decls (FILE *, int);
 454
 455 /* In tree-phinodes.c  */
 456 extern void reserve_phi_args_for_new_edge (basic_block);
 457 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 458 extern gimple create_phi_node (tree, basic_block);
 459 extern void add_phi_arg (gimple, tree, edge, source_location);
 460 extern void remove_phi_args (edge);
 461 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 462 extern void remove_phi_nodes (basic_block);
 463 extern void release_phi_node (gimple);
 464 extern void phinodes_print_statistics (void);
 465
 466 /* In gimple-low.c  */
 467 extern void record_vars_into (tree, tree);
 468 extern void record_vars (tree);
 469 extern bool gimple_seq_may_fallthru (gimple_seq);
 470 extern bool gimple_stmt_may_fallthru (gimple);
 471 extern bool gimple_check_call_matching_types (gimple, tree);
 472
 473
 474 /* In tree-ssa.c  */
 475
 476 /* Mapping for redirected edges.  */
 477 struct _edge_var_map {
 478   tree result;                  /* PHI result.  */
 479   tree def;                     /* PHI arg definition.  */
 480   source_location locus;        /* PHI arg location.  */
 481 };
 482 typedef struct _edge_var_map edge_var_map;
 483
 484 DEF_VEC_O(edge_var_map);
 485 DEF_VEC_ALLOC_O(edge_var_map, heap);
 486
 487 /* A vector of var maps.  */
 488 typedef VEC(edge_var_map, heap) *edge_var_map_vector;
 489
 490 extern void init_tree_ssa (struct function *);
 491 extern void redirect_edge_var_map_add (edge, tree, tree, source_location);
 492 extern void redirect_edge_var_map_clear (edge);
 493 extern void redirect_edge_var_map_dup (edge, edge);
 494 extern edge_var_map_vector redirect_edge_var_map_vector (edge);
 495 extern void redirect_edge_var_map_destroy (void);
 496
 497 extern edge ssa_redirect_edge (edge, basic_block);
 498 extern void flush_pending_stmts (edge);
 499 extern void verify_ssa (bool);
 500 extern void delete_tree_ssa (void);
 501 extern bool ssa_undefined_value_p (tree);
 502 extern void warn_uninit (enum opt_code, tree, tree, tree, const char *, void *);
 503 extern unsigned int warn_uninitialized_vars (bool);
 504 extern void execute_update_addresses_taken (void);
 505
 506 /* Call-back function for walk_use_def_chains().  At each reaching
 507    definition, a function with this prototype is called.  */
 508 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *);
 509
 510 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 511
 512 void insert_debug_temps_for_defs (gimple_stmt_iterator *);
 513 void insert_debug_temp_for_var_def (gimple_stmt_iterator *, tree);
 514 void reset_debug_uses (gimple);
 515 void release_defs_bitset (bitmap toremove);
 516
 517 /* In tree-into-ssa.c  */
 518 void update_ssa (unsigned);
 519 void delete_update_ssa (void);
 520 void register_new_name_mapping (tree, tree);
 521 tree create_new_def_for (tree, gimple, def_operand_p);
 522 bool need_ssa_update_p (struct function *);
 523 bool name_registered_for_update_p (tree);
 524 void release_ssa_name_after_update_ssa (tree);
 525 void compute_global_livein (bitmap, bitmap);
 526 void mark_virtual_operands_for_renaming (struct function *);
 527 tree get_current_def (tree);
 528 void set_current_def (tree, tree);
 529
 530 /* In tree-ssanames.c  */
 531 extern void init_ssanames (struct function *, int);
 532 extern void fini_ssanames (void);
 533 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 534 extern tree duplicate_ssa_name (tree, gimple);
 535 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 536 extern void release_ssa_name (tree);
 537 extern void release_defs (gimple);
 538 extern void replace_ssa_name_symbol (tree, tree);
 539 extern bool get_ptr_info_alignment (struct ptr_info_def *, unsigned int *,
 540                                     unsigned int *);
 541 extern void mark_ptr_info_alignment_unknown (struct ptr_info_def *);
 542 extern void set_ptr_info_alignment (struct ptr_info_def *, unsigned int,
 543                                     unsigned int);
 544 extern void adjust_ptr_info_misalignment (struct ptr_info_def *,
 545                                           unsigned int);
 546
 547 extern void ssanames_print_statistics (void);
 548
 549 /* In tree-ssa-ccp.c  */
 550 tree fold_const_aggregate_ref (tree);
 551 tree gimple_fold_stmt_to_constant (gimple, tree (*)(tree));
 552
 553 /* In tree-ssa-dom.c  */
 554 extern void dump_dominator_optimization_stats (FILE *);
 555 extern void debug_dominator_optimization_stats (void);
 556 int loop_depth_of_name (tree);
 557 tree degenerate_phi_result (gimple);
 558 bool simple_iv_increment_p (gimple);
 559
 560 /* In tree-ssa-copy.c  */
 561 extern void propagate_value (use_operand_p, tree);
 562 extern void propagate_tree_value (tree *, tree);
 563 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 564 extern void replace_exp (use_operand_p, tree);
 565 extern bool may_propagate_copy (tree, tree);
 566 extern bool may_propagate_copy_into_stmt (gimple, tree);
 567 extern bool may_propagate_copy_into_asm (tree);
 568
 569 /* In tree-ssa-loop-ch.c  */
 570 bool do_while_loop_p (struct loop *);
 571
 572 /* Affine iv.  */
 573
 574 typedef struct
 575 {
 576   /* Iv = BASE + STEP * i.  */
 577   tree base, step;
 578
 579   /* True if this iv does not overflow.  */
 580   bool no_overflow;
 581 } affine_iv;
 582
 583 /* Description of number of iterations of a loop.  All the expressions inside
 584    the structure can be evaluated at the end of the loop's preheader
 585    (and due to ssa form, also anywhere inside the body of the loop).  */
 586
 587 struct tree_niter_desc
 588 {
 589   tree assumptions;     /* The boolean expression.  If this expression evaluates
 590                            to false, then the other fields in this structure
 591                            should not be used; there is no guarantee that they
 592                            will be correct.  */
 593   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 594                            the loop will exit in the first iteration (i.e.
 595                            its latch will not be executed), even if the niter
 596                            field says otherwise.  */
 597   tree niter;           /* The expression giving the number of iterations of
 598                            a loop (provided that assumptions == true and
 599                            may_be_zero == false), more precisely the number
 600                            of executions of the latch of the loop.  */
 601   double_int max;       /* The upper bound on the number of iterations of
 602                            the loop.  */
 603
 604   /* The simplified shape of the exit condition.  The loop exits if
 605      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 606      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 607      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 608      by loop unrolling.  */
 609   affine_iv control;
 610   tree bound;
 611   enum tree_code cmp;
 612 };
 613
 614 /* In tree-ssa-phiopt.c */
 615 bool empty_block_p (basic_block);
 616 basic_block *blocks_in_phiopt_order (void);
 617
 618 /* In tree-ssa-loop*.c  */
 619
 620 unsigned int tree_ssa_lim (void);
 621 unsigned int tree_ssa_unswitch_loops (void);
 622 unsigned int canonicalize_induction_variables (void);
 623 unsigned int tree_unroll_loops_completely (bool, bool);
 624 unsigned int tree_ssa_prefetch_arrays (void);
 625 void tree_ssa_iv_optimize (void);
 626 unsigned tree_predictive_commoning (void);
 627 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 628 bool parallelize_loops (void);
 629
 630 bool loop_only_exit_p (const struct loop *, const_edge);
 631 bool number_of_iterations_exit (struct loop *, edge,
 632                                 struct tree_niter_desc *niter, bool);
 633 tree find_loop_niter (struct loop *, edge *);
 634 tree loop_niter_by_eval (struct loop *, edge);
 635 tree find_loop_niter_by_eval (struct loop *, edge *);
 636 void estimate_numbers_of_iterations (void);
 637 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 638 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 639
 640 bool nowrap_type_p (tree);
 641 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 642 enum ev_direction scev_direction (const_tree);
 643
 644 void free_numbers_of_iterations_estimates (void);
 645 void free_numbers_of_iterations_estimates_loop (struct loop *);
 646 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 647 void verify_loop_closed_ssa (bool);
 648 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 649 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 650                 tree *, tree *);
 651 basic_block split_loop_exit_edge (edge);
 652 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 653                                      bool *);
 654 basic_block ip_end_pos (struct loop *);
 655 basic_block ip_normal_pos (struct loop *);
 656 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 657                                          unsigned int, sbitmap,
 658                                          edge, VEC (edge, heap) **,
 659                                          int);
 660 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 661 void rename_variables_in_loop (struct loop *);
 662 void rename_variables_in_bb (basic_block bb);
 663 tree expand_simple_operations (tree);
 664 void substitute_in_loop_info (struct loop *, tree, tree);
 665 edge single_dom_exit (struct loop *);
 666 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 667                         struct tree_niter_desc *niter);
 668 void tree_unroll_loop (struct loop *, unsigned,
 669                        edge, struct tree_niter_desc *);
 670 typedef void (*transform_callback)(struct loop *, void *);
 671 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 672                                      edge, struct tree_niter_desc *,
 673                                      transform_callback, void *);
 674 bool contains_abnormal_ssa_name_p (tree);
 675 bool stmt_dominates_stmt_p (gimple, gimple);
 676
 677 /* In tree-ssa-dce.c */
 678 void mark_virtual_operand_for_renaming (tree);
 679 void mark_virtual_phi_result_for_renaming (gimple);
 680
 681 /* In tree-ssa-threadedge.c */
 682 extern void threadedge_initialize_values (void);
 683 extern void threadedge_finalize_values (void);
 684 extern VEC(tree,heap) *ssa_name_values;
 685 #define SSA_NAME_VALUE(x) \
 686     (SSA_NAME_VERSION(x) < VEC_length(tree, ssa_name_values) \
 687      ? VEC_index(tree, ssa_name_values, SSA_NAME_VERSION(x)) \
 688      : NULL_TREE)
 689 extern void set_ssa_name_value (tree, tree);
 690 extern bool potentially_threadable_block (basic_block);
 691 extern void thread_across_edge (gimple, edge, bool,
 692                                 VEC(tree, heap) **, tree (*) (gimple, gimple));
 693
 694 /* In tree-ssa-loop-im.c  */
 695 /* The possibilities of statement movement.  */
 696
 697 enum move_pos
 698   {
 699     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 700     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 701                                    become executed -- memory accesses, ... */
 702     MOVE_POSSIBLE               /* Unlimited movement.  */
 703   };
 704 extern enum move_pos movement_possibility (gimple);
 705 char *get_lsm_tmp_name (tree, unsigned);
 706
 707 /* In tree-flow-inline.h  */
 708 static inline bool unmodifiable_var_p (const_tree);
 709 static inline bool ref_contains_array_ref (const_tree);
 710
 711 /* In tree-eh.c  */
 712 extern void make_eh_edges (gimple);
 713 extern bool make_eh_dispatch_edges (gimple);
 714 extern edge redirect_eh_edge (edge, basic_block);
 715 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 716 extern bool stmt_could_throw_p (gimple);
 717 extern bool stmt_can_throw_internal (gimple);
 718 extern bool stmt_can_throw_external (gimple);
 719 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 720 extern void add_stmt_to_eh_lp (gimple, int);
 721 extern bool remove_stmt_from_eh_lp (gimple);
 722 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 723 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 724 extern int lookup_stmt_eh_lp (gimple);
 725 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 726 extern bool maybe_clean_eh_stmt (gimple);
 727 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 728 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 729                                         struct function *, gimple,
 730                                         struct pointer_map_t *, int);
 731 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 732 extern bool verify_eh_edges (gimple);
 733 extern bool verify_eh_dispatch_edge (gimple);
 734 extern void maybe_remove_unreachable_handlers (void);
 735
 736 /* In tree-ssa-pre.c  */
 737 void debug_value_expressions (unsigned int);
 738
 739 /* In tree-loop-linear.c  */
 740 extern void linear_transform_loops (void);
 741 extern unsigned perfect_loop_nest_depth (struct loop *);
 742
 743 /* In graphite.c  */
 744 extern void graphite_transform_loops (void);
 745
 746 /* In tree-data-ref.c  */
 747 extern void tree_check_data_deps (void);
 748
 749 /* In tree-ssa-loop-ivopts.c  */
 750 bool expr_invariant_in_loop_p (struct loop *, tree);
 751 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 752 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 753                                       addr_space_t);
 754 bool may_be_nonaddressable_p (tree expr);
 755
 756 /* In tree-ssa-threadupdate.c.  */
 757 extern bool thread_through_all_blocks (bool);
 758 extern void register_jump_thread (edge, edge, edge);
 759
 760 /* In gimplify.c  */
 761 tree force_gimple_operand_1 (tree, gimple_seq *, gimple_predicate, tree);
 762 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 763 tree force_gimple_operand_gsi_1 (gimple_stmt_iterator *, tree,
 764                                  gimple_predicate, tree,
 765                                  bool, enum gsi_iterator_update);
 766 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 767                                bool, enum gsi_iterator_update);
 768 tree gimple_fold_indirect_ref (tree);
 769
 770 /* In tree-ssa-live.c */
 771 extern void remove_unused_locals (void);
 772 extern void dump_scope_blocks (FILE *, int);
 773 extern void debug_scope_blocks (int);
 774 extern void debug_scope_block (tree, int);
 775
 776 /* In tree-ssa-address.c  */
 777
 778 /* Description of a memory address.  */
 779
 780 struct mem_address
 781 {
 782   tree symbol, base, index, step, offset;
 783 };
 784
 785 struct affine_tree_combination;
 786 tree create_mem_ref (gimple_stmt_iterator *, tree,
 787                      struct affine_tree_combination *, tree, tree, tree, bool);
 788 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 789 void get_address_description (tree, struct mem_address *);
 790 tree maybe_fold_tmr (tree);
 791
 792 unsigned int execute_fixup_cfg (void);
 793 bool fixup_noreturn_call (gimple stmt);
 794
 795 /* In ipa-pure-const.c  */
 796 void warn_function_noreturn (tree);
 797
 798 /* In tree-ssa-ter.c  */
 799 bool stmt_is_replaceable_p (gimple);
 800
 801 /* In tree-parloops.c  */
 802 bool parallelized_function_p (tree);
 803
 804 #include "tree-flow-inline.h"
 805
 806 void swap_tree_operands (gimple, tree *, tree *);
 807
 808 #endif /* _TREE_FLOW_H  */