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 /* 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   VEC(tree,gc) *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   /* True if IPA points-to information was computed for this function.  */
  80   unsigned int ipa_pta : 1;
  81
  82   struct ssa_operands ssa_operands;
  83 };
  84
  85 /* Accessors for internal use only.  Generic code should use abstraction
  86    provided by tree-flow-inline.h or specific modules.  */
  87 #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames
  88 #define SSANAMES(fun) (fun)->gimple_df->ssa_names
  89 #define MODIFIED_NORETURN_CALLS(fun) (fun)->gimple_df->modified_noreturn_calls
  90 #define DEFAULT_DEFS(fun) (fun)->gimple_df->default_defs
  91 #define SYMS_TO_RENAME(fun) (fun)->gimple_df->syms_to_rename
  92
  93 typedef struct
  94 {
  95   htab_t htab;
  96   PTR *slot;
  97   PTR *limit;
  98 } htab_iterator;
  99
 100 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
 101    storing each element in RESULT, which is of type TYPE.  */
 102 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
 103   for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
 104         !end_htab_p (&(ITER)); \
 105         RESULT = (TYPE) next_htab_element (&(ITER)))
 106
 107 /*---------------------------------------------------------------------------
 108                       Attributes for SSA_NAMEs.
 109
 110   NOTE: These structures are stored in struct tree_ssa_name
 111   but are only used by the tree optimizers, so it makes better sense
 112   to declare them here to avoid recompiling unrelated files when
 113   making changes.
 114 ---------------------------------------------------------------------------*/
 115
 116 /* Aliasing information for SSA_NAMEs representing pointer variables.  */
 117
 118 struct GTY(()) ptr_info_def
 119 {
 120   /* The points-to solution.  */
 121   struct pt_solution pt;
 122
 123   /* Alignment and misalignment of the pointer in bytes.  Together
 124      align and misalign specify low known bits of the pointer.
 125      ptr & (align - 1) == misalign.  */
 126
 127   /* The power-of-two byte alignment of the object this pointer
 128      points into.  This is usually DECL_ALIGN_UNIT for decls and
 129      MALLOC_ABI_ALIGNMENT for allocated storage.  */
 130   unsigned int align;
 131
 132   /* The byte offset this pointer differs from the above alignment.  */
 133   unsigned int misalign;
 134 };
 135
 136
 137 /* It is advantageous to avoid things like life analysis for variables which
 138    do not need PHI nodes.  This enum describes whether or not a particular
 139    variable may need a PHI node.  */
 140
 141 enum need_phi_state {
 142   /* This is the default.  If we are still in this state after finding
 143      all the definition and use sites, then we will assume the variable
 144      needs PHI nodes.  This is probably an overly conservative assumption.  */
 145   NEED_PHI_STATE_UNKNOWN,
 146
 147   /* This state indicates that we have seen one or more sets of the
 148      variable in a single basic block and that the sets dominate all
 149      uses seen so far.  If after finding all definition and use sites
 150      we are still in this state, then the variable does not need any
 151      PHI nodes.  */
 152   NEED_PHI_STATE_NO,
 153
 154   /* This state indicates that we have either seen multiple definitions of
 155      the variable in multiple blocks, or that we encountered a use in a
 156      block that was not dominated by the block containing the set(s) of
 157      this variable.  This variable is assumed to need PHI nodes.  */
 158   NEED_PHI_STATE_MAYBE
 159 };
 160
 161
 162 struct GTY(()) var_ann_d {
 163   /* Used when building base variable structures in a var_map.  */
 164   unsigned base_var_processed : 1;
 165
 166   /* Nonzero if this variable was used after SSA optimizations were
 167      applied.  We set this when translating out of SSA form.  */
 168   unsigned used : 1;
 169
 170   /* This field indicates whether or not the variable may need PHI nodes.
 171      See the enum's definition for more detailed information about the
 172      states.  */
 173   ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
 174
 175   /* Used by var_map for the base index of ssa base variables.  */
 176   unsigned base_index;
 177
 178   /* During into-ssa and the dominator optimizer, this field holds the
 179      current version of this variable (an SSA_NAME).  */
 180   tree current_def;
 181 };
 182
 183
 184 /* Immediate use lists are used to directly access all uses for an SSA
 185    name and get pointers to the statement for each use.
 186
 187    The structure ssa_use_operand_d consists of PREV and NEXT pointers
 188    to maintain the list.  A USE pointer, which points to address where
 189    the use is located and a LOC pointer which can point to the
 190    statement where the use is located, or, in the case of the root
 191    node, it points to the SSA name itself.
 192
 193    The list is anchored by an occurrence of ssa_operand_d *in* the
 194    ssa_name node itself (named 'imm_uses').  This node is uniquely
 195    identified by having a NULL USE pointer. and the LOC pointer
 196    pointing back to the ssa_name node itself.  This node forms the
 197    base for a circular list, and initially this is the only node in
 198    the list.
 199
 200    Fast iteration allows each use to be examined, but does not allow
 201    any modifications to the uses or stmts.
 202
 203    Normal iteration allows insertion, deletion, and modification. the
 204    iterator manages this by inserting a marker node into the list
 205    immediately before the node currently being examined in the list.
 206    this marker node is uniquely identified by having null stmt *and* a
 207    null use pointer.
 208
 209    When iterating to the next use, the iteration routines check to see
 210    if the node after the marker has changed. if it has, then the node
 211    following the marker is now the next one to be visited. if not, the
 212    marker node is moved past that node in the list (visualize it as
 213    bumping the marker node through the list).  this continues until
 214    the marker node is moved to the original anchor position. the
 215    marker node is then removed from the list.
 216
 217    If iteration is halted early, the marker node must be removed from
 218    the list before continuing.  */
 219 typedef struct immediate_use_iterator_d
 220 {
 221   /* This is the current use the iterator is processing.  */
 222   ssa_use_operand_t *imm_use;
 223   /* This marks the last use in the list (use node from SSA_NAME)  */
 224   ssa_use_operand_t *end_p;
 225   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 226   ssa_use_operand_t iter_node;
 227   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 228      the next one is traversed to, so it must be cached early.  */
 229   ssa_use_operand_t *next_imm_name;
 230 } imm_use_iterator;
 231
 232
 233 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 234    modifying stmts will cause this iterator to malfunction.  */
 235
 236 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)               \
 237   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 238        !end_readonly_imm_use_p (&(ITER));                       \
 239        (void) ((DEST) = next_readonly_imm_use (&(ITER))))
 240
 241 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 242
 243 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 244   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 245        !end_imm_use_stmt_p (&(ITER));                           \
 246        (void) ((STMT) = next_imm_use_stmt (&(ITER))))
 247
 248 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 249    do so will result in leaving a iterator marker node in the immediate
 250    use list, and nothing good will come from that.   */
 251 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 252    {                                                            \
 253      end_imm_use_stmt_traverse (&(ITER));                       \
 254      break;                                                     \
 255    }
 256
 257
 258 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 259    get access to each occurrence of ssavar on the stmt returned by
 260    that iterator..  for instance:
 261
 262      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 263        {
 264          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 265            {
 266              SET_USE (use_p, blah);
 267            }
 268          update_stmt (stmt);
 269        }                                                         */
 270
 271 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 272   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 273        !end_imm_use_on_stmt_p (&(ITER));                        \
 274        (void) ((DEST) = next_imm_use_on_stmt (&(ITER))))
 275
 276
 277
 278 typedef struct var_ann_d *var_ann_t;
 279
 280 static inline var_ann_t var_ann (const_tree);
 281 static inline var_ann_t get_var_ann (tree);
 282 static inline void update_stmt (gimple);
 283 static inline int get_lineno (const_gimple);
 284
 285 /* Accessors for basic block annotations.  */
 286 static inline gimple_seq phi_nodes (const_basic_block);
 287 static inline void set_phi_nodes (basic_block, gimple_seq);
 288
 289 /*---------------------------------------------------------------------------
 290                               Global declarations
 291 ---------------------------------------------------------------------------*/
 292 struct int_tree_map {
 293   unsigned int uid;
 294   tree to;
 295 };
 296
 297 extern unsigned int int_tree_map_hash (const void *);
 298 extern int int_tree_map_eq (const void *, const void *);
 299
 300 extern unsigned int uid_decl_map_hash (const void *);
 301 extern int uid_decl_map_eq (const void *, const void *);
 302
 303 typedef struct
 304 {
 305   htab_iterator hti;
 306 } referenced_var_iterator;
 307
 308 /* This macro loops over all the referenced vars, one at a time, putting the
 309    current var in VAR.  Note:  You are not allowed to add referenced variables
 310    to the hashtable while using this macro.  Doing so may cause it to behave
 311    erratically.  */
 312
 313 #define FOR_EACH_REFERENCED_VAR(FN, VAR, ITER)          \
 314   for ((VAR) = first_referenced_var ((FN), &(ITER));    \
 315        !end_referenced_vars_p (&(ITER));                \
 316        (VAR) = next_referenced_var (&(ITER)))
 317
 318 extern tree referenced_var_lookup (struct function *, unsigned int);
 319 extern bool referenced_var_check_and_insert (tree);
 320 #define num_referenced_vars htab_elements (gimple_referenced_vars (cfun))
 321
 322 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
 323 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
 324
 325 /* Macros for showing usage statistics.  */
 326 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 327                   ? (x)                                 \
 328                   : ((x) < 1024*1024*10                 \
 329                      ? (x) / 1024                       \
 330                      : (x) / (1024*1024))))
 331
 332 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 333
 334 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 335
 336 /*---------------------------------------------------------------------------
 337                               OpenMP Region Tree
 338 ---------------------------------------------------------------------------*/
 339
 340 /* Parallel region information.  Every parallel and workshare
 341    directive is enclosed between two markers, the OMP_* directive
 342    and a corresponding OMP_RETURN statement.  */
 343
 344 struct omp_region
 345 {
 346   /* The enclosing region.  */
 347   struct omp_region *outer;
 348
 349   /* First child region.  */
 350   struct omp_region *inner;
 351
 352   /* Next peer region.  */
 353   struct omp_region *next;
 354
 355   /* Block containing the omp directive as its last stmt.  */
 356   basic_block entry;
 357
 358   /* Block containing the OMP_RETURN as its last stmt.  */
 359   basic_block exit;
 360
 361   /* Block containing the OMP_CONTINUE as its last stmt.  */
 362   basic_block cont;
 363
 364   /* If this is a combined parallel+workshare region, this is a list
 365      of additional arguments needed by the combined parallel+workshare
 366      library call.  */
 367   VEC(tree,gc) *ws_args;
 368
 369   /* The code for the omp directive of this region.  */
 370   enum gimple_code type;
 371
 372   /* Schedule kind, only used for OMP_FOR type regions.  */
 373   enum omp_clause_schedule_kind sched_kind;
 374
 375   /* True if this is a combined parallel+workshare region.  */
 376   bool is_combined_parallel;
 377 };
 378
 379 extern struct omp_region *root_omp_region;
 380 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 381                                           struct omp_region *);
 382 extern void free_omp_regions (void);
 383 void omp_expand_local (basic_block);
 384 extern tree find_omp_clause (tree, enum omp_clause_code);
 385 tree copy_var_decl (tree, tree, tree);
 386
 387 /*---------------------------------------------------------------------------
 388                               Function prototypes
 389 ---------------------------------------------------------------------------*/
 390 /* In tree-cfg.c  */
 391
 392 /* Location to track pending stmt for edge insertion.  */
 393 #define PENDING_STMT(e) ((e)->insns.g)
 394
 395 extern void delete_tree_cfg_annotations (void);
 396 extern bool stmt_ends_bb_p (gimple);
 397 extern bool is_ctrl_stmt (gimple);
 398 extern bool is_ctrl_altering_stmt (gimple);
 399 extern bool simple_goto_p (gimple);
 400 extern bool stmt_can_make_abnormal_goto (gimple);
 401 extern basic_block single_noncomplex_succ (basic_block bb);
 402 extern void gimple_dump_bb (basic_block, FILE *, int, int);
 403 extern void gimple_debug_bb (basic_block);
 404 extern basic_block gimple_debug_bb_n (int);
 405 extern void gimple_dump_cfg (FILE *, int);
 406 extern void gimple_debug_cfg (int);
 407 extern void dump_cfg_stats (FILE *);
 408 extern void dot_cfg (void);
 409 extern void debug_cfg_stats (void);
 410 extern void debug_loops (int);
 411 extern void debug_loop (struct loop *, int);
 412 extern void debug_loop_num (unsigned, int);
 413 extern void print_loops (FILE *, int);
 414 extern void print_loops_bb (FILE *, basic_block, int, int);
 415 extern void cleanup_dead_labels (void);
 416 extern void group_case_labels (void);
 417 extern gimple first_stmt (basic_block);
 418 extern gimple last_stmt (basic_block);
 419 extern gimple last_and_only_stmt (basic_block);
 420 extern edge find_taken_edge (basic_block, tree);
 421 extern basic_block label_to_block_fn (struct function *, tree);
 422 #define label_to_block(t) (label_to_block_fn (cfun, t))
 423 extern void notice_special_calls (gimple);
 424 extern void clear_special_calls (void);
 425 extern void verify_gimple_in_seq (gimple_seq);
 426 extern void verify_gimple_in_cfg (struct function *);
 427 extern tree gimple_block_label (basic_block);
 428 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 429 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 430                                         basic_block *);
 431 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 432                                       basic_block *);
 433 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 434                                           VEC(basic_block,heap) **bbs_p);
 435 extern void add_phi_args_after_copy_bb (basic_block);
 436 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 437 extern bool gimple_purge_dead_eh_edges (basic_block);
 438 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 439 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 440 extern bool gimple_purge_all_dead_abnormal_call_edges (const_bitmap);
 441 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 442                              tree, tree);
 443 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 444                              tree, tree, tree);
 445 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 446                              tree, tree, tree, tree);
 447 extern void init_empty_tree_cfg (void);
 448 extern void init_empty_tree_cfg_for_function (struct function *);
 449 extern void fold_cond_expr_cond (void);
 450 extern void make_abnormal_goto_edges (basic_block, bool);
 451 extern void replace_uses_by (tree, tree);
 452 extern void start_recording_case_labels (void);
 453 extern void end_recording_case_labels (void);
 454 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 455                                            basic_block, tree);
 456 void remove_edge_and_dominated_blocks (edge);
 457 bool tree_node_can_be_shared (tree);
 458
 459 /* In tree-cfgcleanup.c  */
 460 extern bitmap cfgcleanup_altered_bbs;
 461 extern bool cleanup_tree_cfg (void);
 462
 463 /* In tree-pretty-print.c.  */
 464 extern void dump_generic_bb (FILE *, basic_block, int, int);
 465 extern int op_code_prio (enum tree_code);
 466 extern int op_prio (const_tree);
 467 extern const char *op_symbol_code (enum tree_code);
 468
 469 /* In tree-dfa.c  */
 470 extern var_ann_t create_var_ann (tree);
 471 extern void renumber_gimple_stmt_uids (void);
 472 extern void renumber_gimple_stmt_uids_in_blocks (basic_block *, int);
 473 extern void dump_dfa_stats (FILE *);
 474 extern void debug_dfa_stats (void);
 475 extern void debug_referenced_vars (void);
 476 extern void dump_referenced_vars (FILE *);
 477 extern void dump_variable (FILE *, tree);
 478 extern void debug_variable (tree);
 479 extern tree get_virtual_var (tree);
 480 extern bool add_referenced_var (tree);
 481 extern void remove_referenced_var (tree);
 482 extern void mark_symbols_for_renaming (gimple);
 483 extern void find_new_referenced_vars (gimple);
 484 extern tree make_rename_temp (tree, const char *);
 485 extern void set_default_def (tree, tree);
 486 extern tree gimple_default_def (struct function *, tree);
 487 extern bool stmt_references_abnormal_ssa_name (gimple);
 488 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
 489                                      HOST_WIDE_INT *, HOST_WIDE_INT *);
 490 extern tree get_addr_base_and_unit_offset (tree, HOST_WIDE_INT *);
 491 extern void find_referenced_vars_in (gimple);
 492
 493 /* In tree-phinodes.c  */
 494 extern void reserve_phi_args_for_new_edge (basic_block);
 495 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 496 extern gimple make_phi_node (tree var, int len);
 497 extern gimple create_phi_node (tree, basic_block);
 498 extern void add_phi_arg (gimple, tree, edge, source_location);
 499 extern void remove_phi_args (edge);
 500 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 501 extern void remove_phi_nodes (basic_block);
 502 extern void init_phinodes (void);
 503 extern void fini_phinodes (void);
 504 extern void release_phi_node (gimple);
 505 #ifdef GATHER_STATISTICS
 506 extern void phinodes_print_statistics (void);
 507 #endif
 508
 509 /* In gimple-low.c  */
 510 extern void record_vars_into (tree, tree);
 511 extern void record_vars (tree);
 512 extern bool gimple_seq_may_fallthru (gimple_seq);
 513 extern bool gimple_stmt_may_fallthru (gimple);
 514 extern bool gimple_check_call_matching_types (gimple, tree);
 515
 516
 517 /* In tree-ssa.c  */
 518
 519 /* Mapping for redirected edges.  */
 520 struct _edge_var_map {
 521   tree result;                  /* PHI result.  */
 522   tree def;                     /* PHI arg definition.  */
 523   source_location locus;        /* PHI arg location.  */
 524 };
 525 typedef struct _edge_var_map edge_var_map;
 526
 527 DEF_VEC_O(edge_var_map);
 528 DEF_VEC_ALLOC_O(edge_var_map, heap);
 529
 530 /* A vector of var maps.  */
 531 typedef VEC(edge_var_map, heap) *edge_var_map_vector;
 532
 533 extern void init_tree_ssa (struct function *);
 534 extern void redirect_edge_var_map_add (edge, tree, tree, source_location);
 535 extern void redirect_edge_var_map_clear (edge);
 536 extern void redirect_edge_var_map_dup (edge, edge);
 537 extern edge_var_map_vector redirect_edge_var_map_vector (edge);
 538 extern void redirect_edge_var_map_destroy (void);
 539
 540 extern edge ssa_redirect_edge (edge, basic_block);
 541 extern void flush_pending_stmts (edge);
 542 extern void verify_ssa (bool);
 543 extern void delete_tree_ssa (void);
 544 extern bool ssa_undefined_value_p (tree);
 545 extern void warn_uninit (enum opt_code, tree, const char *, void *);
 546 extern unsigned int warn_uninitialized_vars (bool);
 547 extern void execute_update_addresses_taken (void);
 548
 549 /* Call-back function for walk_use_def_chains().  At each reaching
 550    definition, a function with this prototype is called.  */
 551 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *);
 552
 553 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 554
 555 void insert_debug_temps_for_defs (gimple_stmt_iterator *);
 556 void insert_debug_temp_for_var_def (gimple_stmt_iterator *, tree);
 557 void reset_debug_uses (gimple);
 558 void release_defs_bitset (bitmap toremove);
 559
 560 /* In tree-into-ssa.c  */
 561 void update_ssa (unsigned);
 562 void delete_update_ssa (void);
 563 void register_new_name_mapping (tree, tree);
 564 tree create_new_def_for (tree, gimple, def_operand_p);
 565 bool need_ssa_update_p (struct function *);
 566 bool name_mappings_registered_p (void);
 567 bool name_registered_for_update_p (tree);
 568 bitmap ssa_names_to_replace (void);
 569 void release_ssa_name_after_update_ssa (tree);
 570 void compute_global_livein (bitmap, bitmap);
 571 void mark_sym_for_renaming (tree);
 572 void mark_set_for_renaming (bitmap);
 573 bool symbol_marked_for_renaming (tree);
 574 tree get_current_def (tree);
 575 void set_current_def (tree, tree);
 576
 577 /* In tree-ssanames.c  */
 578 extern void init_ssanames (struct function *, int);
 579 extern void fini_ssanames (void);
 580 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 581 extern tree duplicate_ssa_name (tree, gimple);
 582 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 583 extern void release_ssa_name (tree);
 584 extern void release_defs (gimple);
 585 extern void replace_ssa_name_symbol (tree, tree);
 586
 587 #ifdef GATHER_STATISTICS
 588 extern void ssanames_print_statistics (void);
 589 #endif
 590
 591 /* In tree-ssa-ccp.c  */
 592 tree fold_const_aggregate_ref (tree);
 593 tree gimple_fold_stmt_to_constant (gimple, tree (*)(tree));
 594
 595 /* In tree-ssa-dom.c  */
 596 extern void dump_dominator_optimization_stats (FILE *);
 597 extern void debug_dominator_optimization_stats (void);
 598 int loop_depth_of_name (tree);
 599 tree degenerate_phi_result (gimple);
 600
 601 /* In tree-ssa-copy.c  */
 602 extern void propagate_value (use_operand_p, tree);
 603 extern void propagate_tree_value (tree *, tree);
 604 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 605 extern void replace_exp (use_operand_p, tree);
 606 extern bool may_propagate_copy (tree, tree);
 607 extern bool may_propagate_copy_into_stmt (gimple, tree);
 608 extern bool may_propagate_copy_into_asm (tree);
 609
 610 /* Affine iv.  */
 611
 612 typedef struct
 613 {
 614   /* Iv = BASE + STEP * i.  */
 615   tree base, step;
 616
 617   /* True if this iv does not overflow.  */
 618   bool no_overflow;
 619 } affine_iv;
 620
 621 /* Description of number of iterations of a loop.  All the expressions inside
 622    the structure can be evaluated at the end of the loop's preheader
 623    (and due to ssa form, also anywhere inside the body of the loop).  */
 624
 625 struct tree_niter_desc
 626 {
 627   tree assumptions;     /* The boolean expression.  If this expression evaluates
 628                            to false, then the other fields in this structure
 629                            should not be used; there is no guarantee that they
 630                            will be correct.  */
 631   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 632                            the loop will exit in the first iteration (i.e.
 633                            its latch will not be executed), even if the niter
 634                            field says otherwise.  */
 635   tree niter;           /* The expression giving the number of iterations of
 636                            a loop (provided that assumptions == true and
 637                            may_be_zero == false), more precisely the number
 638                            of executions of the latch of the loop.  */
 639   double_int max;       /* The upper bound on the number of iterations of
 640                            the loop.  */
 641
 642   /* The simplified shape of the exit condition.  The loop exits if
 643      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 644      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 645      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 646      by loop unrolling.  */
 647   affine_iv control;
 648   tree bound;
 649   enum tree_code cmp;
 650 };
 651
 652 /* In tree-ssa-phiopt.c */
 653 bool empty_block_p (basic_block);
 654 basic_block *blocks_in_phiopt_order (void);
 655
 656 /* In tree-ssa-loop*.c  */
 657
 658 unsigned int tree_ssa_lim (void);
 659 unsigned int tree_ssa_unswitch_loops (void);
 660 unsigned int canonicalize_induction_variables (void);
 661 unsigned int tree_unroll_loops_completely (bool, bool);
 662 unsigned int tree_ssa_prefetch_arrays (void);
 663 void tree_ssa_iv_optimize (void);
 664 unsigned tree_predictive_commoning (void);
 665 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 666 bool parallelize_loops (void);
 667
 668 bool loop_only_exit_p (const struct loop *, const_edge);
 669 bool number_of_iterations_exit (struct loop *, edge,
 670                                 struct tree_niter_desc *niter, bool);
 671 tree find_loop_niter (struct loop *, edge *);
 672 tree loop_niter_by_eval (struct loop *, edge);
 673 tree find_loop_niter_by_eval (struct loop *, edge *);
 674 void estimate_numbers_of_iterations (bool);
 675 bool array_at_struct_end_p (tree);
 676 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 677 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 678
 679 bool nowrap_type_p (tree);
 680 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 681 enum ev_direction scev_direction (const_tree);
 682
 683 void free_numbers_of_iterations_estimates (void);
 684 void free_numbers_of_iterations_estimates_loop (struct loop *);
 685 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 686 void verify_loop_closed_ssa (bool);
 687 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 688 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 689                 tree *, tree *);
 690 basic_block split_loop_exit_edge (edge);
 691 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 692                                      bool *);
 693 basic_block ip_end_pos (struct loop *);
 694 basic_block ip_normal_pos (struct loop *);
 695 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 696                                          unsigned int, sbitmap,
 697                                          edge, VEC (edge, heap) **,
 698                                          int);
 699 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 700 void rename_variables_in_loop (struct loop *);
 701 void rename_variables_in_bb (basic_block bb);
 702 struct loop *tree_ssa_loop_version (struct loop *, tree,
 703                                     basic_block *);
 704 tree expand_simple_operations (tree);
 705 void substitute_in_loop_info (struct loop *, tree, tree);
 706 edge single_dom_exit (struct loop *);
 707 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 708                         struct tree_niter_desc *niter);
 709 void tree_unroll_loop (struct loop *, unsigned,
 710                        edge, struct tree_niter_desc *);
 711 typedef void (*transform_callback)(struct loop *, void *);
 712 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 713                                      edge, struct tree_niter_desc *,
 714                                      transform_callback, void *);
 715 bool contains_abnormal_ssa_name_p (tree);
 716 bool stmt_dominates_stmt_p (gimple, gimple);
 717 void mark_virtual_ops_for_renaming (gimple);
 718
 719 /* In tree-ssa-dce.c */
 720 void mark_virtual_phi_result_for_renaming (gimple);
 721
 722 /* In tree-ssa-threadedge.c */
 723 extern void threadedge_initialize_values (void);
 724 extern void threadedge_finalize_values (void);
 725 extern VEC(tree,heap) *ssa_name_values;
 726 #define SSA_NAME_VALUE(x) \
 727     (SSA_NAME_VERSION(x) < VEC_length(tree, ssa_name_values) \
 728      ? VEC_index(tree, ssa_name_values, SSA_NAME_VERSION(x)) \
 729      : NULL_TREE)
 730 extern void set_ssa_name_value (tree, tree);
 731 extern bool potentially_threadable_block (basic_block);
 732 extern void thread_across_edge (gimple, edge, bool,
 733                                 VEC(tree, heap) **, tree (*) (gimple, gimple));
 734
 735 /* In tree-ssa-loop-im.c  */
 736 /* The possibilities of statement movement.  */
 737
 738 enum move_pos
 739   {
 740     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 741     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 742                                    become executed -- memory accesses, ... */
 743     MOVE_POSSIBLE               /* Unlimited movement.  */
 744   };
 745 extern enum move_pos movement_possibility (gimple);
 746 char *get_lsm_tmp_name (tree, unsigned);
 747
 748 /* In tree-flow-inline.h  */
 749 static inline void set_is_used (tree);
 750 static inline bool unmodifiable_var_p (const_tree);
 751 static inline bool ref_contains_array_ref (const_tree);
 752
 753 /* In tree-eh.c  */
 754 extern void make_eh_edges (gimple);
 755 extern bool make_eh_dispatch_edges (gimple);
 756 extern edge redirect_eh_edge (edge, basic_block);
 757 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 758 extern bool tree_could_trap_p (tree);
 759 extern bool operation_could_trap_helper_p (enum tree_code, bool, bool, bool,
 760                                            bool, tree, bool *);
 761 extern bool operation_could_trap_p (enum tree_code, bool, bool, tree);
 762 extern bool stmt_could_throw_p (gimple);
 763 extern bool tree_could_throw_p (tree);
 764 extern bool stmt_can_throw_internal (gimple);
 765 extern bool stmt_can_throw_external (gimple);
 766 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 767 extern void add_stmt_to_eh_lp (gimple, int);
 768 extern bool remove_stmt_from_eh_lp (gimple);
 769 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 770 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 771 extern int lookup_stmt_eh_lp (gimple);
 772 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 773 extern bool maybe_clean_eh_stmt (gimple);
 774 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 775 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 776                                         struct function *, gimple,
 777                                         struct pointer_map_t *, int);
 778 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 779 extern bool verify_eh_edges (gimple);
 780 extern bool verify_eh_dispatch_edge (gimple);
 781
 782 /* In tree-ssa-pre.c  */
 783 struct pre_expr_d;
 784 void add_to_value (unsigned int, struct pre_expr_d *);
 785 void debug_value_expressions (unsigned int);
 786 void print_value_expressions (FILE *, unsigned int);
 787
 788 /* In tree-ssa-sink.c  */
 789 bool is_hidden_global_store (gimple);
 790
 791 /* In tree-loop-linear.c  */
 792 extern void linear_transform_loops (void);
 793 extern unsigned perfect_loop_nest_depth (struct loop *);
 794
 795 /* In graphite.c  */
 796 extern void graphite_transform_loops (void);
 797
 798 /* In tree-data-ref.c  */
 799 extern void tree_check_data_deps (void);
 800
 801 /* In tree-ssa-loop-ivopts.c  */
 802 bool expr_invariant_in_loop_p (struct loop *, tree);
 803 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 804 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 805                                       addr_space_t);
 806 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode, bool);
 807 bool may_be_nonaddressable_p (tree expr);
 808
 809 /* In tree-ssa-threadupdate.c.  */
 810 extern bool thread_through_all_blocks (bool);
 811 extern void register_jump_thread (edge, edge);
 812
 813 /* In gimplify.c  */
 814 tree force_gimple_operand_1 (tree, gimple_seq *, gimple_predicate, tree);
 815 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 816 tree force_gimple_operand_gsi_1 (gimple_stmt_iterator *, tree,
 817                                  gimple_predicate, tree,
 818                                  bool, enum gsi_iterator_update);
 819 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 820                                bool, enum gsi_iterator_update);
 821 tree gimple_fold_indirect_ref (tree);
 822
 823 /* In tree-ssa-live.c */
 824 extern void remove_unused_locals (void);
 825 extern void dump_scope_blocks (FILE *, int);
 826 extern void debug_scope_blocks (int);
 827 extern void debug_scope_block (tree, int);
 828
 829 /* In tree-ssa-address.c  */
 830
 831 /* Description of a memory address.  */
 832
 833 struct mem_address
 834 {
 835   tree symbol, base, index, step, offset;
 836 };
 837
 838 struct affine_tree_combination;
 839 tree create_mem_ref (gimple_stmt_iterator *, tree,
 840                      struct affine_tree_combination *, tree, tree, tree, bool);
 841 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 842 void get_address_description (tree, struct mem_address *);
 843 tree maybe_fold_tmr (tree);
 844
 845 unsigned int execute_free_datastructures (void);
 846 unsigned int execute_fixup_cfg (void);
 847 bool fixup_noreturn_call (gimple stmt);
 848
 849 /* In ipa-pure-const.c  */
 850 void warn_function_noreturn (tree);
 851
 852 /* In tree-ssa-ter.c  */
 853 bool stmt_is_replaceable_p (gimple);
 854
 855 #include "tree-flow-inline.h"
 856
 857 void swap_tree_operands (gimple, tree *, tree *);
 858
 859 #endif /* _TREE_FLOW_H  */