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    2012 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, va_gc> *modified_noreturn_calls;
  54
  55   /* Array of all SSA_NAMEs used in the function.  */
  56   vec<tree, va_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, va_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_safe_length (cfun->gimple_df->ssa_names))
 293 #define ssa_name(i) ((*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, va_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> *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 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> 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
 614 /* In tree-ssa-loop*.c  */
 615
 616 unsigned int tree_ssa_lim (void);
 617 unsigned int tree_ssa_unswitch_loops (void);
 618 unsigned int canonicalize_induction_variables (void);
 619 unsigned int tree_unroll_loops_completely (bool, bool);
 620 unsigned int tree_ssa_prefetch_arrays (void);
 621 void tree_ssa_iv_optimize (void);
 622 unsigned tree_predictive_commoning (void);
 623 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 624 bool parallelize_loops (void);
 625
 626 bool loop_only_exit_p (const struct loop *, const_edge);
 627 bool number_of_iterations_exit (struct loop *, edge,
 628                                 struct tree_niter_desc *niter, bool,
 629                                 bool every_iteration = true);
 630 tree find_loop_niter (struct loop *, edge *);
 631 tree loop_niter_by_eval (struct loop *, edge);
 632 tree find_loop_niter_by_eval (struct loop *, edge *);
 633 void estimate_numbers_of_iterations (void);
 634 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 635 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 636
 637 bool nowrap_type_p (tree);
 638 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 639 enum ev_direction scev_direction (const_tree);
 640
 641 void free_numbers_of_iterations_estimates (void);
 642 void free_numbers_of_iterations_estimates_loop (struct loop *);
 643 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 644 void verify_loop_closed_ssa (bool);
 645 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 646 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 647                 tree *, tree *);
 648 basic_block split_loop_exit_edge (edge);
 649 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 650                                      bool *);
 651 basic_block ip_end_pos (struct loop *);
 652 basic_block ip_normal_pos (struct loop *);
 653 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 654                                          unsigned int, sbitmap,
 655                                          edge, vec<edge> *,
 656                                          int);
 657 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 658 void rename_variables_in_loop (struct loop *);
 659 void rename_variables_in_bb (basic_block bb);
 660 tree expand_simple_operations (tree);
 661 void substitute_in_loop_info (struct loop *, tree, tree);
 662 edge single_dom_exit (struct loop *);
 663 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 664                         struct tree_niter_desc *niter);
 665 void tree_unroll_loop (struct loop *, unsigned,
 666                        edge, struct tree_niter_desc *);
 667 typedef void (*transform_callback)(struct loop *, void *);
 668 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 669                                      edge, struct tree_niter_desc *,
 670                                      transform_callback, void *);
 671 bool contains_abnormal_ssa_name_p (tree);
 672 bool stmt_dominates_stmt_p (gimple, gimple);
 673
 674 /* In tree-ssa-dce.c */
 675 void mark_virtual_operand_for_renaming (tree);
 676 void mark_virtual_phi_result_for_renaming (gimple);
 677
 678 /* In tree-ssa-threadedge.c */
 679 extern void threadedge_initialize_values (void);
 680 extern void threadedge_finalize_values (void);
 681 extern vec<tree> ssa_name_values;
 682 #define SSA_NAME_VALUE(x) \
 683     (SSA_NAME_VERSION(x) < ssa_name_values.length () \
 684      ? ssa_name_values[SSA_NAME_VERSION(x)] \
 685      : NULL_TREE)
 686 extern void set_ssa_name_value (tree, tree);
 687 extern bool potentially_threadable_block (basic_block);
 688 extern void thread_across_edge (gimple, edge, bool,
 689                                 vec<tree> *, tree (*) (gimple, gimple));
 690 extern void propagate_threaded_block_debug_into (basic_block, basic_block);
 691
 692 /* In tree-ssa-loop-im.c  */
 693 /* The possibilities of statement movement.  */
 694
 695 enum move_pos
 696   {
 697     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 698     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 699                                    become executed -- memory accesses, ... */
 700     MOVE_POSSIBLE               /* Unlimited movement.  */
 701   };
 702 extern enum move_pos movement_possibility (gimple);
 703 char *get_lsm_tmp_name (tree, unsigned);
 704
 705 /* In tree-flow-inline.h  */
 706 static inline bool unmodifiable_var_p (const_tree);
 707 static inline bool ref_contains_array_ref (const_tree);
 708
 709 /* In tree-eh.c  */
 710 extern void make_eh_edges (gimple);
 711 extern bool make_eh_dispatch_edges (gimple);
 712 extern edge redirect_eh_edge (edge, basic_block);
 713 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 714 extern bool stmt_could_throw_p (gimple);
 715 extern bool stmt_can_throw_internal (gimple);
 716 extern bool stmt_can_throw_external (gimple);
 717 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 718 extern void add_stmt_to_eh_lp (gimple, int);
 719 extern bool remove_stmt_from_eh_lp (gimple);
 720 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 721 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 722 extern int lookup_stmt_eh_lp (gimple);
 723 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 724 extern bool maybe_clean_eh_stmt (gimple);
 725 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 726 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 727                                         struct function *, gimple,
 728                                         struct pointer_map_t *, int);
 729 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 730 extern bool verify_eh_edges (gimple);
 731 extern bool verify_eh_dispatch_edge (gimple);
 732 extern void maybe_remove_unreachable_handlers (void);
 733
 734 /* In tree-ssa-pre.c  */
 735 void debug_value_expressions (unsigned int);
 736
 737 /* In tree-loop-linear.c  */
 738 extern void linear_transform_loops (void);
 739 extern unsigned perfect_loop_nest_depth (struct loop *);
 740
 741 /* In graphite.c  */
 742 extern void graphite_transform_loops (void);
 743
 744 /* In tree-data-ref.c  */
 745 extern void tree_check_data_deps (void);
 746
 747 /* In tree-ssa-loop-ivopts.c  */
 748 bool expr_invariant_in_loop_p (struct loop *, tree);
 749 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 750 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 751                                       addr_space_t);
 752 bool may_be_nonaddressable_p (tree expr);
 753
 754 /* In tree-ssa-threadupdate.c.  */
 755 extern bool thread_through_all_blocks (bool);
 756 extern void register_jump_thread (edge, edge, edge);
 757
 758 /* In gimplify.c  */
 759 tree force_gimple_operand_1 (tree, gimple_seq *, gimple_predicate, tree);
 760 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 761 tree force_gimple_operand_gsi_1 (gimple_stmt_iterator *, tree,
 762                                  gimple_predicate, tree,
 763                                  bool, enum gsi_iterator_update);
 764 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 765                                bool, enum gsi_iterator_update);
 766 tree gimple_fold_indirect_ref (tree);
 767
 768 /* In tree-ssa-live.c */
 769 extern void remove_unused_locals (void);
 770 extern void dump_scope_blocks (FILE *, int);
 771 extern void debug_scope_blocks (int);
 772 extern void debug_scope_block (tree, int);
 773
 774 /* In tree-ssa-address.c  */
 775
 776 /* Description of a memory address.  */
 777
 778 struct mem_address
 779 {
 780   tree symbol, base, index, step, offset;
 781 };
 782
 783 struct affine_tree_combination;
 784 tree create_mem_ref (gimple_stmt_iterator *, tree,
 785                      struct affine_tree_combination *, tree, tree, tree, bool);
 786 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 787 void get_address_description (tree, struct mem_address *);
 788 tree maybe_fold_tmr (tree);
 789
 790 unsigned int execute_fixup_cfg (void);
 791 bool fixup_noreturn_call (gimple stmt);
 792
 793 /* In ipa-pure-const.c  */
 794 void warn_function_noreturn (tree);
 795
 796 /* In tree-ssa-ter.c  */
 797 bool stmt_is_replaceable_p (gimple);
 798
 799 /* In tree-parloops.c  */
 800 bool parallelized_function_p (tree);
 801
 802 #include "tree-flow-inline.h"
 803
 804 void swap_tree_operands (gimple, tree *, tree *);
 805
 806 #endif /* _TREE_FLOW_H  */