gcc/tree-flow.h

   1 /* Data and Control Flow Analysis for Trees.
   2    Copyright (C) 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
   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 "hard-reg-set.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 /* Gimple dataflow datastructure. All publicly available fields shall have
  37    gimple_ accessor defined in tree-flow-inline.h, all publicly modifiable
  38    fields should have gimple_set accessor.  */
  39 struct GTY(()) gimple_df {
  40   /* Array of all variables referenced in the function.  */
  41   htab_t GTY((param_is (union tree_node))) referenced_vars;
  42
  43   /* A vector of all the noreturn calls passed to modify_stmt.
  44      cleanup_control_flow uses it to detect cases where a mid-block
  45      indirect call has been turned into a noreturn call.  When this
  46      happens, all the instructions after the call are no longer
  47      reachable and must be deleted as dead.  */
  48   VEC(gimple,gc) *modified_noreturn_calls;
  49
  50   /* Array of all SSA_NAMEs used in the function.  */
  51   VEC(tree,gc) *ssa_names;
  52
  53   /* Artificial variable used for the virtual operand FUD chain.  */
  54   tree vop;
  55
  56   /* The PTA solution for the ESCAPED artificial variable.  */
  57   struct pt_solution escaped;
  58
  59   /* A map of decls to artificial ssa-names that point to the partition
  60      of the decl.  */
  61   struct pointer_map_t * GTY((skip(""))) decls_to_pointers;
  62
  63   /* Free list of SSA_NAMEs.  */
  64   tree free_ssanames;
  65
  66   /* Hashtable holding definition for symbol.  If this field is not NULL, it
  67      means that the first reference to this variable in the function is a
  68      USE or a VUSE.  In those cases, the SSA renamer creates an SSA name
  69      for this variable with an empty defining statement.  */
  70   htab_t GTY((param_is (union tree_node))) default_defs;
  71
  72   /* Symbols whose SSA form needs to be updated or created for the first
  73      time.  */
  74   bitmap syms_to_rename;
  75
  76   /* True if the code is in ssa form.  */
  77   unsigned int in_ssa_p : 1;
  78
  79   struct ssa_operands ssa_operands;
  80 };
  81
  82 /* Accessors for internal use only.  Generic code should use abstraction
  83    provided by tree-flow-inline.h or specific modules.  */
  84 #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames
  85 #define SSANAMES(fun) (fun)->gimple_df->ssa_names
  86 #define MODIFIED_NORETURN_CALLS(fun) (fun)->gimple_df->modified_noreturn_calls
  87 #define DEFAULT_DEFS(fun) (fun)->gimple_df->default_defs
  88 #define SYMS_TO_RENAME(fun) (fun)->gimple_df->syms_to_rename
  89
  90 typedef struct
  91 {
  92   htab_t htab;
  93   PTR *slot;
  94   PTR *limit;
  95 } htab_iterator;
  96
  97 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
  98    storing each element in RESULT, which is of type TYPE.  */
  99 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
 100   for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
 101         !end_htab_p (&(ITER)); \
 102         RESULT = (TYPE) next_htab_element (&(ITER)))
 103
 104 /*---------------------------------------------------------------------------
 105                       Attributes for SSA_NAMEs.
 106
 107   NOTE: These structures are stored in struct tree_ssa_name
 108   but are only used by the tree optimizers, so it makes better sense
 109   to declare them here to avoid recompiling unrelated files when
 110   making changes.
 111 ---------------------------------------------------------------------------*/
 112
 113 /* Aliasing information for SSA_NAMEs representing pointer variables.  */
 114 struct GTY(()) ptr_info_def
 115 {
 116   /* The points-to solution, TBAA-pruned if the pointer is dereferenced.  */
 117   struct pt_solution pt;
 118 };
 119
 120
 121 /* It is advantageous to avoid things like life analysis for variables which
 122    do not need PHI nodes.  This enum describes whether or not a particular
 123    variable may need a PHI node.  */
 124
 125 enum need_phi_state {
 126   /* This is the default.  If we are still in this state after finding
 127      all the definition and use sites, then we will assume the variable
 128      needs PHI nodes.  This is probably an overly conservative assumption.  */
 129   NEED_PHI_STATE_UNKNOWN,
 130
 131   /* This state indicates that we have seen one or more sets of the
 132      variable in a single basic block and that the sets dominate all
 133      uses seen so far.  If after finding all definition and use sites
 134      we are still in this state, then the variable does not need any
 135      PHI nodes.  */
 136   NEED_PHI_STATE_NO,
 137
 138   /* This state indicates that we have either seen multiple definitions of
 139      the variable in multiple blocks, or that we encountered a use in a
 140      block that was not dominated by the block containing the set(s) of
 141      this variable.  This variable is assumed to need PHI nodes.  */
 142   NEED_PHI_STATE_MAYBE
 143 };
 144
 145
 146 /* The "no alias" attribute allows alias analysis to make more
 147    aggressive assumptions when assigning alias sets, computing
 148    points-to information and memory partitions.  These attributes
 149    are the result of user annotations or flags (e.g.,
 150    -fargument-noalias).  */
 151 enum noalias_state {
 152     /* Default state.  No special assumptions can be made about this
 153        symbol.  */
 154     MAY_ALIAS = 0,
 155
 156     /* The symbol does not alias with other symbols that have a
 157        NO_ALIAS* attribute.  */
 158     NO_ALIAS,
 159
 160     /* The symbol does not alias with other symbols that have a
 161        NO_ALIAS*, and it may not alias with global symbols.  */
 162     NO_ALIAS_GLOBAL,
 163
 164     /* The symbol does not alias with any other symbols.  */
 165     NO_ALIAS_ANYTHING
 166 };
 167
 168
 169 struct GTY(()) var_ann_d {
 170   /* Used when building base variable structures in a var_map.  */
 171   unsigned base_var_processed : 1;
 172
 173   /* Nonzero if this variable was used after SSA optimizations were
 174      applied.  We set this when translating out of SSA form.  */
 175   unsigned used : 1;
 176
 177   /* This field indicates whether or not the variable may need PHI nodes.
 178      See the enum's definition for more detailed information about the
 179      states.  */
 180   ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
 181
 182   /* True for HEAP artificial variables.  These variables represent
 183      the memory area allocated by a call to malloc.  */
 184   unsigned is_heapvar : 1;
 185
 186   /* This field describes several "no alias" attributes that some
 187      symbols are known to have.  See the enum's definition for more
 188      information on each attribute.  */
 189   ENUM_BITFIELD (noalias_state) noalias_state : 2;
 190
 191   /* Used by var_map for the base index of ssa base variables.  */
 192   unsigned base_index;
 193
 194   /* During into-ssa and the dominator optimizer, this field holds the
 195      current version of this variable (an SSA_NAME).  */
 196   tree current_def;
 197 };
 198
 199
 200 /* Immediate use lists are used to directly access all uses for an SSA
 201    name and get pointers to the statement for each use.
 202
 203    The structure ssa_use_operand_d consists of PREV and NEXT pointers
 204    to maintain the list.  A USE pointer, which points to address where
 205    the use is located and a LOC pointer which can point to the
 206    statement where the use is located, or, in the case of the root
 207    node, it points to the SSA name itself.
 208
 209    The list is anchored by an occurrence of ssa_operand_d *in* the
 210    ssa_name node itself (named 'imm_uses').  This node is uniquely
 211    identified by having a NULL USE pointer. and the LOC pointer
 212    pointing back to the ssa_name node itself.  This node forms the
 213    base for a circular list, and initially this is the only node in
 214    the list.
 215
 216    Fast iteration allows each use to be examined, but does not allow
 217    any modifications to the uses or stmts.
 218
 219    Normal iteration allows insertion, deletion, and modification. the
 220    iterator manages this by inserting a marker node into the list
 221    immediately before the node currently being examined in the list.
 222    this marker node is uniquely identified by having null stmt *and* a
 223    null use pointer.
 224
 225    When iterating to the next use, the iteration routines check to see
 226    if the node after the marker has changed. if it has, then the node
 227    following the marker is now the next one to be visited. if not, the
 228    marker node is moved past that node in the list (visualize it as
 229    bumping the marker node through the list).  this continues until
 230    the marker node is moved to the original anchor position. the
 231    marker node is then removed from the list.
 232
 233    If iteration is halted early, the marker node must be removed from
 234    the list before continuing.  */
 235 typedef struct immediate_use_iterator_d
 236 {
 237   /* This is the current use the iterator is processing.  */
 238   ssa_use_operand_t *imm_use;
 239   /* This marks the last use in the list (use node from SSA_NAME)  */
 240   ssa_use_operand_t *end_p;
 241   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 242   ssa_use_operand_t iter_node;
 243   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 244      the next one is traversed to, so it must be cached early.  */
 245   ssa_use_operand_t *next_imm_name;
 246 } imm_use_iterator;
 247
 248
 249 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 250    modifying stmts will cause this iterator to malfunction.  */
 251
 252 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)               \
 253   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 254        !end_readonly_imm_use_p (&(ITER));                       \
 255        (void) ((DEST) = next_readonly_imm_use (&(ITER))))
 256
 257 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 258
 259 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 260   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 261        !end_imm_use_stmt_p (&(ITER));                           \
 262        (void) ((STMT) = next_imm_use_stmt (&(ITER))))
 263
 264 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 265    do so will result in leaving a iterator marker node in the immediate
 266    use list, and nothing good will come from that.   */
 267 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 268    {                                                            \
 269      end_imm_use_stmt_traverse (&(ITER));                       \
 270      break;                                                     \
 271    }
 272
 273
 274 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 275    get access to each occurrence of ssavar on the stmt returned by
 276    that iterator..  for instance:
 277
 278      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 279        {
 280          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 281            {
 282              SET_USE (use_p, blah);
 283            }
 284          update_stmt (stmt);
 285        }                                                         */
 286
 287 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 288   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 289        !end_imm_use_on_stmt_p (&(ITER));                        \
 290        (void) ((DEST) = next_imm_use_on_stmt (&(ITER))))
 291
 292
 293
 294 typedef struct var_ann_d *var_ann_t;
 295
 296 static inline var_ann_t var_ann (const_tree);
 297 static inline var_ann_t get_var_ann (tree);
 298 static inline void update_stmt (gimple);
 299 static inline int get_lineno (const_gimple);
 300
 301 /*---------------------------------------------------------------------------
 302                   Structure representing predictions in tree level.
 303 ---------------------------------------------------------------------------*/
 304 struct GTY((chain_next ("%h.ep_next"))) edge_prediction {
 305   struct edge_prediction *ep_next;
 306   edge ep_edge;
 307   enum br_predictor ep_predictor;
 308   int ep_probability;
 309 };
 310
 311 /* Accessors for basic block annotations.  */
 312 static inline gimple_seq phi_nodes (const_basic_block);
 313 static inline void set_phi_nodes (basic_block, gimple_seq);
 314
 315 /*---------------------------------------------------------------------------
 316                               Global declarations
 317 ---------------------------------------------------------------------------*/
 318 struct GTY(()) int_tree_map {
 319
 320   unsigned int uid;
 321   tree to;
 322 };
 323
 324 extern unsigned int int_tree_map_hash (const void *);
 325 extern int int_tree_map_eq (const void *, const void *);
 326
 327 extern unsigned int uid_decl_map_hash (const void *);
 328 extern int uid_decl_map_eq (const void *, const void *);
 329
 330 typedef struct
 331 {
 332   htab_iterator hti;
 333 } referenced_var_iterator;
 334
 335 /* This macro loops over all the referenced vars, one at a time, putting the
 336    current var in VAR.  Note:  You are not allowed to add referenced variables
 337    to the hashtable while using this macro.  Doing so may cause it to behave
 338    erratically.  */
 339
 340 #define FOR_EACH_REFERENCED_VAR(VAR, ITER) \
 341   for ((VAR) = first_referenced_var (&(ITER)); \
 342        !end_referenced_vars_p (&(ITER)); \
 343        (VAR) = next_referenced_var (&(ITER)))
 344
 345 extern tree referenced_var_lookup (unsigned int);
 346 extern bool referenced_var_check_and_insert (tree);
 347 #define num_referenced_vars htab_elements (gimple_referenced_vars (cfun))
 348 #define referenced_var(i) referenced_var_lookup (i)
 349
 350 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
 351 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
 352
 353 /* Macros for showing usage statistics.  */
 354 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 355                   ? (x)                                 \
 356                   : ((x) < 1024*1024*10                 \
 357                      ? (x) / 1024                       \
 358                      : (x) / (1024*1024))))
 359
 360 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 361
 362 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 363
 364 /*---------------------------------------------------------------------------
 365                               OpenMP Region Tree
 366 ---------------------------------------------------------------------------*/
 367
 368 /* Parallel region information.  Every parallel and workshare
 369    directive is enclosed between two markers, the OMP_* directive
 370    and a corresponding OMP_RETURN statement.  */
 371
 372 struct omp_region
 373 {
 374   /* The enclosing region.  */
 375   struct omp_region *outer;
 376
 377   /* First child region.  */
 378   struct omp_region *inner;
 379
 380   /* Next peer region.  */
 381   struct omp_region *next;
 382
 383   /* Block containing the omp directive as its last stmt.  */
 384   basic_block entry;
 385
 386   /* Block containing the OMP_RETURN as its last stmt.  */
 387   basic_block exit;
 388
 389   /* Block containing the OMP_CONTINUE as its last stmt.  */
 390   basic_block cont;
 391
 392   /* If this is a combined parallel+workshare region, this is a list
 393      of additional arguments needed by the combined parallel+workshare
 394      library call.  */
 395   tree ws_args;
 396
 397   /* The code for the omp directive of this region.  */
 398   enum gimple_code type;
 399
 400   /* Schedule kind, only used for OMP_FOR type regions.  */
 401   enum omp_clause_schedule_kind sched_kind;
 402
 403   /* True if this is a combined parallel+workshare region.  */
 404   bool is_combined_parallel;
 405 };
 406
 407 extern struct omp_region *root_omp_region;
 408 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 409                                           struct omp_region *);
 410 extern void free_omp_regions (void);
 411 void omp_expand_local (basic_block);
 412 extern tree find_omp_clause (tree, enum omp_clause_code);
 413 tree copy_var_decl (tree, tree, tree);
 414
 415 /*---------------------------------------------------------------------------
 416                               Function prototypes
 417 ---------------------------------------------------------------------------*/
 418 /* In tree-cfg.c  */
 419
 420 /* Location to track pending stmt for edge insertion.  */
 421 #define PENDING_STMT(e) ((e)->insns.g)
 422
 423 extern void delete_tree_cfg_annotations (void);
 424 extern bool stmt_ends_bb_p (gimple);
 425 extern bool is_ctrl_stmt (gimple);
 426 extern bool is_ctrl_altering_stmt (gimple);
 427 extern bool simple_goto_p (gimple);
 428 extern bool stmt_can_make_abnormal_goto (gimple);
 429 extern basic_block single_noncomplex_succ (basic_block bb);
 430 extern void gimple_dump_bb (basic_block, FILE *, int, int);
 431 extern void gimple_debug_bb (basic_block);
 432 extern basic_block gimple_debug_bb_n (int);
 433 extern void gimple_dump_cfg (FILE *, int);
 434 extern void gimple_debug_cfg (int);
 435 extern void dump_cfg_stats (FILE *);
 436 extern void dot_cfg (void);
 437 extern void debug_cfg_stats (void);
 438 extern void debug_loops (int);
 439 extern void debug_loop (struct loop *, int);
 440 extern void debug_loop_num (unsigned, int);
 441 extern void print_loops (FILE *, int);
 442 extern void print_loops_bb (FILE *, basic_block, int, int);
 443 extern void cleanup_dead_labels (void);
 444 extern void group_case_labels (void);
 445 extern gimple first_stmt (basic_block);
 446 extern gimple last_stmt (basic_block);
 447 extern gimple last_and_only_stmt (basic_block);
 448 extern edge find_taken_edge (basic_block, tree);
 449 extern basic_block label_to_block_fn (struct function *, tree);
 450 #define label_to_block(t) (label_to_block_fn (cfun, t))
 451 extern void notice_special_calls (gimple);
 452 extern void clear_special_calls (void);
 453 extern void verify_stmts (void);
 454 extern void verify_gimple (void);
 455 extern void verify_types_in_gimple_seq (gimple_seq);
 456 extern tree gimple_block_label (basic_block);
 457 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 458 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 459                                         basic_block *);
 460 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 461                                       basic_block *);
 462 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 463                                           VEC(basic_block,heap) **bbs_p);
 464 extern void add_phi_args_after_copy_bb (basic_block);
 465 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 466 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 467 extern bool gimple_purge_dead_eh_edges (basic_block);
 468 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 469 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 470                              tree, tree);
 471 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 472                              tree, tree, tree);
 473 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 474                              tree, tree, tree, tree);
 475 extern void init_empty_tree_cfg (void);
 476 extern void init_empty_tree_cfg_for_function (struct function *);
 477 extern void fold_cond_expr_cond (void);
 478 extern void make_abnormal_goto_edges (basic_block, bool);
 479 extern void replace_uses_by (tree, tree);
 480 extern void start_recording_case_labels (void);
 481 extern void end_recording_case_labels (void);
 482 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 483                                            basic_block, tree);
 484 void remove_edge_and_dominated_blocks (edge);
 485 void mark_virtual_ops_in_bb (basic_block);
 486 bool tree_node_can_be_shared (tree);
 487
 488 /* In tree-cfgcleanup.c  */
 489 extern bitmap cfgcleanup_altered_bbs;
 490 extern bool cleanup_tree_cfg (void);
 491
 492 /* In tree-pretty-print.c.  */
 493 extern void dump_generic_bb (FILE *, basic_block, int, int);
 494 extern int op_code_prio (enum tree_code);
 495 extern int op_prio (const_tree);
 496 extern const char *op_symbol_code (enum tree_code);
 497
 498 /* In tree-dfa.c  */
 499 extern var_ann_t create_var_ann (tree);
 500 extern void renumber_gimple_stmt_uids (void);
 501 extern void renumber_gimple_stmt_uids_in_blocks (basic_block *, int);
 502 extern void dump_dfa_stats (FILE *);
 503 extern void debug_dfa_stats (void);
 504 extern void debug_referenced_vars (void);
 505 extern void dump_referenced_vars (FILE *);
 506 extern void dump_variable (FILE *, tree);
 507 extern void debug_variable (tree);
 508 extern tree get_virtual_var (tree);
 509 extern bool add_referenced_var (tree);
 510 extern void remove_referenced_var (tree);
 511 extern void mark_symbols_for_renaming (gimple);
 512 extern void find_new_referenced_vars (gimple);
 513 extern tree make_rename_temp (tree, const char *);
 514 extern void set_default_def (tree, tree);
 515 extern tree gimple_default_def (struct function *, tree);
 516 extern bool stmt_references_abnormal_ssa_name (gimple);
 517 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
 518                                      HOST_WIDE_INT *, HOST_WIDE_INT *);
 519 extern void find_referenced_vars_in (gimple);
 520
 521 /* In tree-phinodes.c  */
 522 extern void reserve_phi_args_for_new_edge (basic_block);
 523 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 524 extern gimple make_phi_node (tree var, int len);
 525 extern gimple create_phi_node (tree, basic_block);
 526 extern void add_phi_arg (gimple, tree, edge, source_location);
 527 extern void remove_phi_args (edge);
 528 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 529 extern void remove_phi_nodes (basic_block);
 530 extern void init_phinodes (void);
 531 extern void fini_phinodes (void);
 532 extern void release_phi_node (gimple);
 533 #ifdef GATHER_STATISTICS
 534 extern void phinodes_print_statistics (void);
 535 #endif
 536
 537 /* In gimple-low.c  */
 538 extern void record_vars_into (tree, tree);
 539 extern void record_vars (tree);
 540 extern bool block_may_fallthru (const_tree);
 541 extern bool gimple_seq_may_fallthru (gimple_seq);
 542 extern bool gimple_stmt_may_fallthru (gimple);
 543 extern bool gimple_check_call_args (gimple);
 544
 545
 546 /* In tree-ssa.c  */
 547
 548 /* Mapping for redirected edges.  */
 549 struct GTY(()) _edge_var_map {
 550   tree result;                  /* PHI result.  */
 551   tree def;                     /* PHI arg definition.  */
 552   source_location locus;        /* PHI arg location.  */
 553 };
 554 typedef struct _edge_var_map edge_var_map;
 555
 556 DEF_VEC_O(edge_var_map);
 557 DEF_VEC_ALLOC_O(edge_var_map, heap);
 558
 559 /* A vector of var maps.  */
 560 typedef VEC(edge_var_map, heap) *edge_var_map_vector;
 561
 562 extern void init_tree_ssa (struct function *);
 563 extern void redirect_edge_var_map_add (edge, tree, tree, source_location);
 564 extern void redirect_edge_var_map_clear (edge);
 565 extern void redirect_edge_var_map_dup (edge, edge);
 566 extern edge_var_map_vector redirect_edge_var_map_vector (edge);
 567 extern void redirect_edge_var_map_destroy (void);
 568
 569 extern edge ssa_redirect_edge (edge, basic_block);
 570 extern void flush_pending_stmts (edge);
 571 extern void verify_ssa (bool);
 572 extern void delete_tree_ssa (void);
 573 extern bool ssa_undefined_value_p (tree);
 574 extern void execute_update_addresses_taken (bool);
 575
 576 /* Call-back function for walk_use_def_chains().  At each reaching
 577    definition, a function with this prototype is called.  */
 578 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *);
 579
 580 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 581
 582 void insert_debug_temps_for_defs (gimple_stmt_iterator *);
 583 void insert_debug_temp_for_var_def (gimple_stmt_iterator *, tree);
 584 void release_defs_bitset (bitmap toremove);
 585
 586 /* In tree-into-ssa.c  */
 587 void update_ssa (unsigned);
 588 void delete_update_ssa (void);
 589 void register_new_name_mapping (tree, tree);
 590 tree create_new_def_for (tree, gimple, def_operand_p);
 591 bool need_ssa_update_p (struct function *);
 592 bool name_mappings_registered_p (void);
 593 bool name_registered_for_update_p (tree);
 594 bitmap ssa_names_to_replace (void);
 595 void release_ssa_name_after_update_ssa (tree);
 596 void compute_global_livein (bitmap, bitmap);
 597 void mark_sym_for_renaming (tree);
 598 void mark_set_for_renaming (bitmap);
 599 tree get_current_def (tree);
 600 void set_current_def (tree, tree);
 601
 602 /* In tree-ssanames.c  */
 603 extern void init_ssanames (struct function *, int);
 604 extern void fini_ssanames (void);
 605 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 606 extern tree duplicate_ssa_name (tree, gimple);
 607 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 608 extern void release_ssa_name (tree);
 609 extern void release_defs (gimple);
 610 extern void replace_ssa_name_symbol (tree, tree);
 611
 612 #ifdef GATHER_STATISTICS
 613 extern void ssanames_print_statistics (void);
 614 #endif
 615
 616 /* In tree-ssa-ccp.c  */
 617 tree fold_const_aggregate_ref (tree);
 618
 619 /* In tree-ssa-dom.c  */
 620 extern void dump_dominator_optimization_stats (FILE *);
 621 extern void debug_dominator_optimization_stats (void);
 622 int loop_depth_of_name (tree);
 623 tree degenerate_phi_result (gimple);
 624
 625 /* In tree-ssa-copy.c  */
 626 extern void propagate_value (use_operand_p, tree);
 627 extern void propagate_tree_value (tree *, tree);
 628 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 629 extern void replace_exp (use_operand_p, tree);
 630 extern bool may_propagate_copy (tree, tree);
 631 extern bool may_propagate_copy_into_stmt (gimple, tree);
 632 extern bool may_propagate_copy_into_asm (tree);
 633
 634 /* Affine iv.  */
 635
 636 typedef struct
 637 {
 638   /* Iv = BASE + STEP * i.  */
 639   tree base, step;
 640
 641   /* True if this iv does not overflow.  */
 642   bool no_overflow;
 643 } affine_iv;
 644
 645 /* Description of number of iterations of a loop.  All the expressions inside
 646    the structure can be evaluated at the end of the loop's preheader
 647    (and due to ssa form, also anywhere inside the body of the loop).  */
 648
 649 struct tree_niter_desc
 650 {
 651   tree assumptions;     /* The boolean expression.  If this expression evaluates
 652                            to false, then the other fields in this structure
 653                            should not be used; there is no guarantee that they
 654                            will be correct.  */
 655   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 656                            the loop will exit in the first iteration (i.e.
 657                            its latch will not be executed), even if the niter
 658                            field says otherwise.  */
 659   tree niter;           /* The expression giving the number of iterations of
 660                            a loop (provided that assumptions == true and
 661                            may_be_zero == false), more precisely the number
 662                            of executions of the latch of the loop.  */
 663   double_int max;       /* The upper bound on the number of iterations of
 664                            the loop.  */
 665
 666   /* The simplified shape of the exit condition.  The loop exits if
 667      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 668      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 669      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 670      by loop unrolling.  */
 671   affine_iv control;
 672   tree bound;
 673   enum tree_code cmp;
 674 };
 675
 676 /* In tree-ssa-phiopt.c */
 677 bool empty_block_p (basic_block);
 678 basic_block *blocks_in_phiopt_order (void);
 679
 680 /* In tree-ssa-loop*.c  */
 681
 682 void tree_ssa_lim (void);
 683 unsigned int tree_ssa_unswitch_loops (void);
 684 unsigned int canonicalize_induction_variables (void);
 685 unsigned int tree_unroll_loops_completely (bool, bool);
 686 unsigned int tree_ssa_prefetch_arrays (void);
 687 void tree_ssa_iv_optimize (void);
 688 unsigned tree_predictive_commoning (void);
 689 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 690 bool parallelize_loops (void);
 691
 692 bool loop_only_exit_p (const struct loop *, const_edge);
 693 bool number_of_iterations_exit (struct loop *, edge,
 694                                 struct tree_niter_desc *niter, bool);
 695 tree find_loop_niter (struct loop *, edge *);
 696 tree loop_niter_by_eval (struct loop *, edge);
 697 tree find_loop_niter_by_eval (struct loop *, edge *);
 698 void estimate_numbers_of_iterations (void);
 699 bool array_at_struct_end_p (tree);
 700 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 701 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 702
 703 bool nowrap_type_p (tree);
 704 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 705 enum ev_direction scev_direction (const_tree);
 706
 707 void free_numbers_of_iterations_estimates (void);
 708 void free_numbers_of_iterations_estimates_loop (struct loop *);
 709 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 710 void verify_loop_closed_ssa (bool);
 711 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 712 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 713                 tree *, tree *);
 714 basic_block split_loop_exit_edge (edge);
 715 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 716                                      bool *);
 717 basic_block ip_end_pos (struct loop *);
 718 basic_block ip_normal_pos (struct loop *);
 719 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 720                                          unsigned int, sbitmap,
 721                                          edge, VEC (edge, heap) **,
 722                                          int);
 723 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 724 void rename_variables_in_loop (struct loop *);
 725 void rename_variables_in_bb (basic_block bb);
 726 struct loop *tree_ssa_loop_version (struct loop *, tree,
 727                                     basic_block *);
 728 tree expand_simple_operations (tree);
 729 void substitute_in_loop_info (struct loop *, tree, tree);
 730 edge single_dom_exit (struct loop *);
 731 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 732                         struct tree_niter_desc *niter);
 733 void tree_unroll_loop (struct loop *, unsigned,
 734                        edge, struct tree_niter_desc *);
 735 typedef void (*transform_callback)(struct loop *, void *);
 736 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 737                                      edge, struct tree_niter_desc *,
 738                                      transform_callback, void *);
 739 bool contains_abnormal_ssa_name_p (tree);
 740 bool stmt_dominates_stmt_p (gimple, gimple);
 741 void mark_virtual_ops_for_renaming (gimple);
 742
 743 /* In tree-ssa-dce.c */
 744 void mark_virtual_phi_result_for_renaming (gimple);
 745
 746 /* In tree-ssa-threadedge.c */
 747 extern void threadedge_initialize_values (void);
 748 extern void threadedge_finalize_values (void);
 749 extern VEC(tree,heap) *ssa_name_values;
 750 #define SSA_NAME_VALUE(x) \
 751     (SSA_NAME_VERSION(x) < VEC_length(tree, ssa_name_values) \
 752      ? VEC_index(tree, ssa_name_values, SSA_NAME_VERSION(x)) \
 753      : NULL_TREE)
 754 extern void set_ssa_name_value (tree, tree);
 755 extern bool potentially_threadable_block (basic_block);
 756 extern void thread_across_edge (gimple, edge, bool,
 757                                 VEC(tree, heap) **, tree (*) (gimple, gimple));
 758
 759 /* In tree-ssa-loop-im.c  */
 760 /* The possibilities of statement movement.  */
 761
 762 enum move_pos
 763   {
 764     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 765     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 766                                    become executed -- memory accesses, ... */
 767     MOVE_POSSIBLE               /* Unlimited movement.  */
 768   };
 769 extern enum move_pos movement_possibility (gimple);
 770 char *get_lsm_tmp_name (tree, unsigned);
 771
 772 /* In tree-flow-inline.h  */
 773 static inline bool is_call_clobbered (const_tree);
 774 static inline void set_is_used (tree);
 775 static inline bool unmodifiable_var_p (const_tree);
 776 static inline bool ref_contains_array_ref (const_tree);
 777 static inline bool array_ref_contains_indirect_ref (const_tree);
 778
 779 /* In tree-eh.c  */
 780 extern void make_eh_edges (gimple);
 781 extern bool make_eh_dispatch_edges (gimple);
 782 extern edge redirect_eh_edge (edge, basic_block);
 783 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 784 extern bool tree_could_trap_p (tree);
 785 extern bool operation_could_trap_helper_p (enum tree_code, bool, bool, bool,
 786                                            bool, tree, bool *);
 787 extern bool operation_could_trap_p (enum tree_code, bool, bool, tree);
 788 extern bool stmt_could_throw_p (gimple);
 789 extern bool tree_could_throw_p (tree);
 790 extern bool stmt_can_throw_internal (gimple);
 791 extern bool stmt_can_throw_external (gimple);
 792 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 793 extern void add_stmt_to_eh_lp (gimple, int);
 794 extern bool remove_stmt_from_eh_lp (gimple);
 795 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 796 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 797 extern int lookup_stmt_eh_lp (gimple);
 798 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 799 extern bool maybe_clean_eh_stmt (gimple);
 800 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 801 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 802                                         struct function *, gimple,
 803                                         struct pointer_map_t *, int);
 804 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 805 extern bool verify_eh_edges (gimple);
 806 extern bool verify_eh_dispatch_edge (gimple);
 807
 808 /* In tree-ssa-pre.c  */
 809 struct pre_expr_d;
 810 void add_to_value (unsigned int, struct pre_expr_d *);
 811 void debug_value_expressions (unsigned int);
 812 void print_value_expressions (FILE *, unsigned int);
 813
 814 /* In tree-ssa-sink.c  */
 815 bool is_hidden_global_store (gimple);
 816
 817 /* In tree-loop-linear.c  */
 818 extern void linear_transform_loops (void);
 819 extern unsigned perfect_loop_nest_depth (struct loop *);
 820
 821 /* In graphite.c  */
 822 extern void graphite_transform_loops (void);
 823
 824 /* In tree-data-ref.c  */
 825 extern void tree_check_data_deps (void);
 826
 827 /* In tree-ssa-loop-ivopts.c  */
 828 bool expr_invariant_in_loop_p (struct loop *, tree);
 829 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 830 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 831                                       addr_space_t);
 832 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode, bool);
 833
 834 /* In tree-ssa-threadupdate.c.  */
 835 extern bool thread_through_all_blocks (bool);
 836 extern void register_jump_thread (edge, edge);
 837
 838 /* In gimplify.c  */
 839 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 840 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 841                                bool, enum gsi_iterator_update);
 842 tree gimple_fold_indirect_ref (tree);
 843
 844 /* In tree-ssa-live.c */
 845 extern void remove_unused_locals (void);
 846 extern void dump_scope_blocks (FILE *, int);
 847 extern void debug_scope_blocks (int);
 848 extern void debug_scope_block (tree, int);
 849
 850 /* In tree-ssa-address.c  */
 851
 852 /* Description of a memory address.  */
 853
 854 struct mem_address
 855 {
 856   tree symbol, base, index, step, offset;
 857 };
 858
 859 struct affine_tree_combination;
 860 tree create_mem_ref (gimple_stmt_iterator *, tree,
 861                      struct affine_tree_combination *, tree, bool);
 862 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 863 void get_address_description (tree, struct mem_address *);
 864 tree maybe_fold_tmr (tree);
 865
 866 unsigned int execute_free_datastructures (void);
 867 unsigned int execute_fixup_cfg (void);
 868
 869 #include "tree-flow-inline.h"
 870
 871 void swap_tree_operands (gimple, tree *, tree *);
 872
 873 int least_common_multiple (int, int);
 874
 875 #endif /* _TREE_FLOW_H  */