gcc/tree-flow.h

   1 /* Data and Control Flow Analysis for Trees.
   2    Copyright (C) 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
   3    Free Software Foundation, Inc.
   4    Contributed by Diego Novillo <dnovillo@redhat.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 3, or (at your option)
  11 any later version.
  12
  13 GCC is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #ifndef _TREE_FLOW_H
  23 #define _TREE_FLOW_H 1
  24
  25 #include "bitmap.h"
  26 #include "sbitmap.h"
  27 #include "basic-block.h"
  28 #include "hashtab.h"
  29 #include "gimple.h"
  30 #include "tree-ssa-operands.h"
  31 #include "cgraph.h"
  32 #include "ipa-reference.h"
  33 #include "tree-ssa-alias.h"
  34
  35
  36 /* This structure is used to map a gimple statement to a label,
  37    or list of labels to represent transaction restart.  */
  38
  39 struct GTY(()) tm_restart_node {
  40   gimple stmt;
  41   tree label_or_list;
  42 };
  43
  44 /* Gimple dataflow datastructure. All publicly available fields shall have
  45    gimple_ accessor defined in tree-flow-inline.h, all publicly modifiable
  46    fields should have gimple_set accessor.  */
  47 struct GTY(()) gimple_df {
  48   /* Array of all variables referenced in the function.  */
  49   htab_t GTY((param_is (union tree_node))) referenced_vars;
  50
  51   /* A vector of all the noreturn calls passed to modify_stmt.
  52      cleanup_control_flow uses it to detect cases where a mid-block
  53      indirect call has been turned into a noreturn call.  When this
  54      happens, all the instructions after the call are no longer
  55      reachable and must be deleted as dead.  */
  56   VEC(gimple,gc) *modified_noreturn_calls;
  57
  58   /* Array of all SSA_NAMEs used in the function.  */
  59   VEC(tree,gc) *ssa_names;
  60
  61   /* Artificial variable used for the virtual operand FUD chain.  */
  62   tree vop;
  63
  64   /* The PTA solution for the ESCAPED artificial variable.  */
  65   struct pt_solution escaped;
  66
  67   /* A map of decls to artificial ssa-names that point to the partition
  68      of the decl.  */
  69   struct pointer_map_t * GTY((skip(""))) decls_to_pointers;
  70
  71   /* Free list of SSA_NAMEs.  */
  72   VEC(tree,gc) *free_ssanames;
  73
  74   /* Hashtable holding definition for symbol.  If this field is not NULL, it
  75      means that the first reference to this variable in the function is a
  76      USE or a VUSE.  In those cases, the SSA renamer creates an SSA name
  77      for this variable with an empty defining statement.  */
  78   htab_t GTY((param_is (union tree_node))) default_defs;
  79
  80   /* Symbols whose SSA form needs to be updated or created for the first
  81      time.  */
  82   bitmap syms_to_rename;
  83
  84   /* True if the code is in ssa form.  */
  85   unsigned int in_ssa_p : 1;
  86
  87   /* True if IPA points-to information was computed for this function.  */
  88   unsigned int ipa_pta : 1;
  89
  90   struct ssa_operands ssa_operands;
  91
  92   /* Map gimple stmt to tree label (or list of labels) for transaction
  93      restart and abort.  */
  94   htab_t GTY ((param_is (struct tm_restart_node))) tm_restart;
  95 };
  96
  97 /* Accessors for internal use only.  Generic code should use abstraction
  98    provided by tree-flow-inline.h or specific modules.  */
  99 #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames
 100 #define SSANAMES(fun) (fun)->gimple_df->ssa_names
 101 #define MODIFIED_NORETURN_CALLS(fun) (fun)->gimple_df->modified_noreturn_calls
 102 #define DEFAULT_DEFS(fun) (fun)->gimple_df->default_defs
 103 #define SYMS_TO_RENAME(fun) (fun)->gimple_df->syms_to_rename
 104
 105 typedef struct
 106 {
 107   htab_t htab;
 108   PTR *slot;
 109   PTR *limit;
 110 } htab_iterator;
 111
 112 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
 113    storing each element in RESULT, which is of type TYPE.  */
 114 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
 115   for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
 116         !end_htab_p (&(ITER)); \
 117         RESULT = (TYPE) next_htab_element (&(ITER)))
 118
 119 /*---------------------------------------------------------------------------
 120                       Attributes for SSA_NAMEs.
 121
 122   NOTE: These structures are stored in struct tree_ssa_name
 123   but are only used by the tree optimizers, so it makes better sense
 124   to declare them here to avoid recompiling unrelated files when
 125   making changes.
 126 ---------------------------------------------------------------------------*/
 127
 128 /* Aliasing information for SSA_NAMEs representing pointer variables.  */
 129
 130 struct GTY(()) ptr_info_def
 131 {
 132   /* The points-to solution.  */
 133   struct pt_solution pt;
 134
 135   /* Alignment and misalignment of the pointer in bytes.  Together
 136      align and misalign specify low known bits of the pointer.
 137      ptr & (align - 1) == misalign.  */
 138
 139   /* When known, this is the power-of-two byte alignment of the object this
 140      pointer points into.  This is usually DECL_ALIGN_UNIT for decls and
 141      MALLOC_ABI_ALIGNMENT for allocated storage.  When the alignment is not
 142      known, it is zero.  Do not access directly but use functions
 143      get_ptr_info_alignment, set_ptr_info_alignment,
 144      mark_ptr_info_alignment_unknown and similar.  */
 145   unsigned int align;
 146
 147   /* When alignment is known, the byte offset this pointer differs from the
 148      above alignment.  Access only through the same helper functions as align
 149      above.  */
 150   unsigned int misalign;
 151 };
 152
 153
 154 /* It is advantageous to avoid things like life analysis for variables which
 155    do not need PHI nodes.  This enum describes whether or not a particular
 156    variable may need a PHI node.  */
 157
 158 enum need_phi_state {
 159   /* This is the default.  If we are still in this state after finding
 160      all the definition and use sites, then we will assume the variable
 161      needs PHI nodes.  This is probably an overly conservative assumption.  */
 162   NEED_PHI_STATE_UNKNOWN,
 163
 164   /* This state indicates that we have seen one or more sets of the
 165      variable in a single basic block and that the sets dominate all
 166      uses seen so far.  If after finding all definition and use sites
 167      we are still in this state, then the variable does not need any
 168      PHI nodes.  */
 169   NEED_PHI_STATE_NO,
 170
 171   /* This state indicates that we have either seen multiple definitions of
 172      the variable in multiple blocks, or that we encountered a use in a
 173      block that was not dominated by the block containing the set(s) of
 174      this variable.  This variable is assumed to need PHI nodes.  */
 175   NEED_PHI_STATE_MAYBE
 176 };
 177
 178
 179 struct GTY(()) var_ann_d {
 180   /* Used when building base variable structures in a var_map.  */
 181   unsigned base_var_processed : 1;
 182
 183   /* Nonzero if this variable was used after SSA optimizations were
 184      applied.  We set this when translating out of SSA form.  */
 185   unsigned used : 1;
 186
 187   /* This field indicates whether or not the variable may need PHI nodes.
 188      See the enum's definition for more detailed information about the
 189      states.  */
 190   ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
 191
 192   /* Used by var_map for the base index of ssa base variables.  */
 193   unsigned base_index;
 194
 195   /* During into-ssa and the dominator optimizer, this field holds the
 196      current version of this variable (an SSA_NAME).  */
 197   tree current_def;
 198 };
 199
 200
 201 /* Immediate use lists are used to directly access all uses for an SSA
 202    name and get pointers to the statement for each use.
 203
 204    The structure ssa_use_operand_d consists of PREV and NEXT pointers
 205    to maintain the list.  A USE pointer, which points to address where
 206    the use is located and a LOC pointer which can point to the
 207    statement where the use is located, or, in the case of the root
 208    node, it points to the SSA name itself.
 209
 210    The list is anchored by an occurrence of ssa_operand_d *in* the
 211    ssa_name node itself (named 'imm_uses').  This node is uniquely
 212    identified by having a NULL USE pointer. and the LOC pointer
 213    pointing back to the ssa_name node itself.  This node forms the
 214    base for a circular list, and initially this is the only node in
 215    the list.
 216
 217    Fast iteration allows each use to be examined, but does not allow
 218    any modifications to the uses or stmts.
 219
 220    Normal iteration allows insertion, deletion, and modification. the
 221    iterator manages this by inserting a marker node into the list
 222    immediately before the node currently being examined in the list.
 223    this marker node is uniquely identified by having null stmt *and* a
 224    null use pointer.
 225
 226    When iterating to the next use, the iteration routines check to see
 227    if the node after the marker has changed. if it has, then the node
 228    following the marker is now the next one to be visited. if not, the
 229    marker node is moved past that node in the list (visualize it as
 230    bumping the marker node through the list).  this continues until
 231    the marker node is moved to the original anchor position. the
 232    marker node is then removed from the list.
 233
 234    If iteration is halted early, the marker node must be removed from
 235    the list before continuing.  */
 236 typedef struct immediate_use_iterator_d
 237 {
 238   /* This is the current use the iterator is processing.  */
 239   ssa_use_operand_t *imm_use;
 240   /* This marks the last use in the list (use node from SSA_NAME)  */
 241   ssa_use_operand_t *end_p;
 242   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 243   ssa_use_operand_t iter_node;
 244   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 245      the next one is traversed to, so it must be cached early.  */
 246   ssa_use_operand_t *next_imm_name;
 247 } imm_use_iterator;
 248
 249
 250 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 251    modifying stmts will cause this iterator to malfunction.  */
 252
 253 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)               \
 254   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 255        !end_readonly_imm_use_p (&(ITER));                       \
 256        (void) ((DEST) = next_readonly_imm_use (&(ITER))))
 257
 258 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 259
 260 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 261   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 262        !end_imm_use_stmt_p (&(ITER));                           \
 263        (void) ((STMT) = next_imm_use_stmt (&(ITER))))
 264
 265 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 266    do so will result in leaving a iterator marker node in the immediate
 267    use list, and nothing good will come from that.   */
 268 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 269    {                                                            \
 270      end_imm_use_stmt_traverse (&(ITER));                       \
 271      break;                                                     \
 272    }
 273
 274
 275 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 276    get access to each occurrence of ssavar on the stmt returned by
 277    that iterator..  for instance:
 278
 279      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 280        {
 281          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 282            {
 283              SET_USE (use_p, blah);
 284            }
 285          update_stmt (stmt);
 286        }                                                         */
 287
 288 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 289   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 290        !end_imm_use_on_stmt_p (&(ITER));                        \
 291        (void) ((DEST) = next_imm_use_on_stmt (&(ITER))))
 292
 293
 294
 295 typedef struct var_ann_d *var_ann_t;
 296
 297 static inline var_ann_t var_ann (const_tree);
 298 static inline void update_stmt (gimple);
 299 static inline int get_lineno (const_gimple);
 300
 301 /* Accessors for basic block annotations.  */
 302 static inline gimple_seq phi_nodes (const_basic_block);
 303 static inline void set_phi_nodes (basic_block, gimple_seq);
 304
 305 /*---------------------------------------------------------------------------
 306                               Global declarations
 307 ---------------------------------------------------------------------------*/
 308 struct int_tree_map {
 309   unsigned int uid;
 310   tree to;
 311 };
 312
 313 extern unsigned int int_tree_map_hash (const void *);
 314 extern int int_tree_map_eq (const void *, const void *);
 315
 316 extern unsigned int uid_decl_map_hash (const void *);
 317 extern int uid_decl_map_eq (const void *, const void *);
 318
 319 typedef struct
 320 {
 321   htab_iterator hti;
 322 } referenced_var_iterator;
 323
 324 /* This macro loops over all the referenced vars, one at a time, putting the
 325    current var in VAR.  Note:  You are not allowed to add referenced variables
 326    to the hashtable while using this macro.  Doing so may cause it to behave
 327    erratically.  */
 328
 329 #define FOR_EACH_REFERENCED_VAR(FN, VAR, ITER)          \
 330   for ((VAR) = first_referenced_var ((FN), &(ITER));    \
 331        !end_referenced_vars_p (&(ITER));                \
 332        (VAR) = next_referenced_var (&(ITER)))
 333
 334 extern tree referenced_var_lookup (struct function *, unsigned int);
 335 #define num_referenced_vars htab_elements (gimple_referenced_vars (cfun))
 336
 337 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
 338 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
 339
 340 /* Macros for showing usage statistics.  */
 341 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 342                   ? (x)                                 \
 343                   : ((x) < 1024*1024*10                 \
 344                      ? (x) / 1024                       \
 345                      : (x) / (1024*1024))))
 346
 347 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 348
 349 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 350
 351 /*---------------------------------------------------------------------------
 352                               OpenMP Region Tree
 353 ---------------------------------------------------------------------------*/
 354
 355 /* Parallel region information.  Every parallel and workshare
 356    directive is enclosed between two markers, the OMP_* directive
 357    and a corresponding OMP_RETURN statement.  */
 358
 359 struct omp_region
 360 {
 361   /* The enclosing region.  */
 362   struct omp_region *outer;
 363
 364   /* First child region.  */
 365   struct omp_region *inner;
 366
 367   /* Next peer region.  */
 368   struct omp_region *next;
 369
 370   /* Block containing the omp directive as its last stmt.  */
 371   basic_block entry;
 372
 373   /* Block containing the OMP_RETURN as its last stmt.  */
 374   basic_block exit;
 375
 376   /* Block containing the OMP_CONTINUE as its last stmt.  */
 377   basic_block cont;
 378
 379   /* If this is a combined parallel+workshare region, this is a list
 380      of additional arguments needed by the combined parallel+workshare
 381      library call.  */
 382   VEC(tree,gc) *ws_args;
 383
 384   /* The code for the omp directive of this region.  */
 385   enum gimple_code type;
 386
 387   /* Schedule kind, only used for OMP_FOR type regions.  */
 388   enum omp_clause_schedule_kind sched_kind;
 389
 390   /* True if this is a combined parallel+workshare region.  */
 391   bool is_combined_parallel;
 392 };
 393
 394 extern struct omp_region *root_omp_region;
 395 extern struct omp_region *new_omp_region (basic_block, enum gimple_code,
 396                                           struct omp_region *);
 397 extern void free_omp_regions (void);
 398 void omp_expand_local (basic_block);
 399 extern tree find_omp_clause (tree, enum omp_clause_code);
 400 tree copy_var_decl (tree, tree, tree);
 401
 402 /*---------------------------------------------------------------------------
 403                               Function prototypes
 404 ---------------------------------------------------------------------------*/
 405 /* In tree-cfg.c  */
 406
 407 /* Location to track pending stmt for edge insertion.  */
 408 #define PENDING_STMT(e) ((e)->insns.g)
 409
 410 extern void delete_tree_cfg_annotations (void);
 411 extern bool stmt_ends_bb_p (gimple);
 412 extern bool is_ctrl_stmt (gimple);
 413 extern bool is_ctrl_altering_stmt (gimple);
 414 extern bool simple_goto_p (gimple);
 415 extern bool stmt_can_make_abnormal_goto (gimple);
 416 extern basic_block single_noncomplex_succ (basic_block bb);
 417 extern void gimple_dump_bb (basic_block, FILE *, int, int);
 418 extern void gimple_debug_bb (basic_block);
 419 extern basic_block gimple_debug_bb_n (int);
 420 extern void gimple_dump_cfg (FILE *, int);
 421 extern void gimple_debug_cfg (int);
 422 extern void dump_cfg_stats (FILE *);
 423 extern void dot_cfg (void);
 424 extern void debug_cfg_stats (void);
 425 extern void debug_loops (int);
 426 extern void debug_loop (struct loop *, int);
 427 extern void debug_loop_num (unsigned, int);
 428 extern void print_loops (FILE *, int);
 429 extern void print_loops_bb (FILE *, basic_block, int, int);
 430 extern void cleanup_dead_labels (void);
 431 extern void group_case_labels (void);
 432 extern gimple first_stmt (basic_block);
 433 extern gimple last_stmt (basic_block);
 434 extern gimple last_and_only_stmt (basic_block);
 435 extern edge find_taken_edge (basic_block, tree);
 436 extern basic_block label_to_block_fn (struct function *, tree);
 437 #define label_to_block(t) (label_to_block_fn (cfun, t))
 438 extern void notice_special_calls (gimple);
 439 extern void clear_special_calls (void);
 440 extern void verify_gimple_in_seq (gimple_seq);
 441 extern void verify_gimple_in_cfg (struct function *);
 442 extern tree gimple_block_label (basic_block);
 443 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 444 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 445                                         basic_block *);
 446 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 447                                       basic_block *);
 448 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 449                                           VEC(basic_block,heap) **bbs_p);
 450 extern void add_phi_args_after_copy_bb (basic_block);
 451 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 452 extern bool gimple_purge_dead_eh_edges (basic_block);
 453 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 454 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 455 extern bool gimple_purge_all_dead_abnormal_call_edges (const_bitmap);
 456 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 457                              tree, tree);
 458 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 459                              tree, tree, tree);
 460 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 461                              tree, tree, tree, tree);
 462 extern void init_empty_tree_cfg (void);
 463 extern void init_empty_tree_cfg_for_function (struct function *);
 464 extern void fold_cond_expr_cond (void);
 465 extern void make_abnormal_goto_edges (basic_block, bool);
 466 extern void replace_uses_by (tree, tree);
 467 extern void start_recording_case_labels (void);
 468 extern void end_recording_case_labels (void);
 469 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 470                                            basic_block, tree);
 471 void remove_edge_and_dominated_blocks (edge);
 472 bool tree_node_can_be_shared (tree);
 473
 474 /* In tree-cfgcleanup.c  */
 475 extern bitmap cfgcleanup_altered_bbs;
 476 extern bool cleanup_tree_cfg (void);
 477
 478 /* In tree-pretty-print.c.  */
 479 extern void dump_generic_bb (FILE *, basic_block, int, int);
 480 extern int op_code_prio (enum tree_code);
 481 extern int op_prio (const_tree);
 482 extern const char *op_symbol_code (enum tree_code);
 483
 484 /* In tree-dfa.c  */
 485 extern var_ann_t create_var_ann (tree);
 486 extern void renumber_gimple_stmt_uids (void);
 487 extern void renumber_gimple_stmt_uids_in_blocks (basic_block *, int);
 488 extern void dump_dfa_stats (FILE *);
 489 extern void debug_dfa_stats (void);
 490 extern void debug_referenced_vars (void);
 491 extern void dump_referenced_vars (FILE *);
 492 extern void dump_variable (FILE *, tree);
 493 extern void debug_variable (tree);
 494 extern tree get_virtual_var (tree);
 495 extern bool add_referenced_var (tree);
 496 extern void remove_referenced_var (tree);
 497 extern void mark_symbols_for_renaming (gimple);
 498 extern tree make_rename_temp (tree, const char *);
 499 extern void set_default_def (tree, tree);
 500 extern tree gimple_default_def (struct function *, tree);
 501 extern bool stmt_references_abnormal_ssa_name (gimple);
 502 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
 503                                      HOST_WIDE_INT *, HOST_WIDE_INT *);
 504 extern tree get_addr_base_and_unit_offset (tree, HOST_WIDE_INT *);
 505 extern void find_referenced_vars_in (gimple);
 506
 507 /* In tree-phinodes.c  */
 508 extern void reserve_phi_args_for_new_edge (basic_block);
 509 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 510 extern gimple create_phi_node (tree, basic_block);
 511 extern void add_phi_arg (gimple, tree, edge, source_location);
 512 extern void remove_phi_args (edge);
 513 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 514 extern void remove_phi_nodes (basic_block);
 515 extern void release_phi_node (gimple);
 516 #ifdef GATHER_STATISTICS
 517 extern void phinodes_print_statistics (void);
 518 #endif
 519
 520 /* In gimple-low.c  */
 521 extern void record_vars_into (tree, tree);
 522 extern void record_vars (tree);
 523 extern bool gimple_seq_may_fallthru (gimple_seq);
 524 extern bool gimple_stmt_may_fallthru (gimple);
 525 extern bool gimple_check_call_matching_types (gimple, tree);
 526
 527
 528 /* In tree-ssa.c  */
 529
 530 /* Mapping for redirected edges.  */
 531 struct _edge_var_map {
 532   tree result;                  /* PHI result.  */
 533   tree def;                     /* PHI arg definition.  */
 534   source_location locus;        /* PHI arg location.  */
 535 };
 536 typedef struct _edge_var_map edge_var_map;
 537
 538 DEF_VEC_O(edge_var_map);
 539 DEF_VEC_ALLOC_O(edge_var_map, heap);
 540
 541 /* A vector of var maps.  */
 542 typedef VEC(edge_var_map, heap) *edge_var_map_vector;
 543
 544 extern void init_tree_ssa (struct function *);
 545 extern void redirect_edge_var_map_add (edge, tree, tree, source_location);
 546 extern void redirect_edge_var_map_clear (edge);
 547 extern void redirect_edge_var_map_dup (edge, edge);
 548 extern edge_var_map_vector redirect_edge_var_map_vector (edge);
 549 extern void redirect_edge_var_map_destroy (void);
 550
 551 extern edge ssa_redirect_edge (edge, basic_block);
 552 extern void flush_pending_stmts (edge);
 553 extern void verify_ssa (bool);
 554 extern void delete_tree_ssa (void);
 555 extern bool ssa_undefined_value_p (tree);
 556 extern void warn_uninit (enum opt_code, tree, tree, tree, const char *, void *);
 557 extern unsigned int warn_uninitialized_vars (bool);
 558 extern void execute_update_addresses_taken (void);
 559
 560 /* Call-back function for walk_use_def_chains().  At each reaching
 561    definition, a function with this prototype is called.  */
 562 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *);
 563
 564 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 565
 566 void insert_debug_temps_for_defs (gimple_stmt_iterator *);
 567 void insert_debug_temp_for_var_def (gimple_stmt_iterator *, tree);
 568 void reset_debug_uses (gimple);
 569 void release_defs_bitset (bitmap toremove);
 570
 571 /* In tree-into-ssa.c  */
 572 void update_ssa (unsigned);
 573 void delete_update_ssa (void);
 574 void register_new_name_mapping (tree, tree);
 575 tree create_new_def_for (tree, gimple, def_operand_p);
 576 bool need_ssa_update_p (struct function *);
 577 bool name_mappings_registered_p (void);
 578 bool name_registered_for_update_p (tree);
 579 bitmap ssa_names_to_replace (void);
 580 void release_ssa_name_after_update_ssa (tree);
 581 void compute_global_livein (bitmap, bitmap);
 582 void mark_sym_for_renaming (tree);
 583 void mark_set_for_renaming (bitmap);
 584 bool symbol_marked_for_renaming (tree);
 585 tree get_current_def (tree);
 586 void set_current_def (tree, tree);
 587
 588 /* In tree-ssanames.c  */
 589 extern void init_ssanames (struct function *, int);
 590 extern void fini_ssanames (void);
 591 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 592 extern tree duplicate_ssa_name (tree, gimple);
 593 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 594 extern void release_ssa_name (tree);
 595 extern void release_defs (gimple);
 596 extern void replace_ssa_name_symbol (tree, tree);
 597 extern bool get_ptr_info_alignment (struct ptr_info_def *, unsigned int *,
 598                                     unsigned int *);
 599 extern void mark_ptr_info_alignment_unknown (struct ptr_info_def *);
 600 extern void set_ptr_info_alignment (struct ptr_info_def *, unsigned int,
 601                                     unsigned int);
 602 extern void adjust_ptr_info_misalignment (struct ptr_info_def *,
 603                                           unsigned int);
 604
 605 #ifdef GATHER_STATISTICS
 606 extern void ssanames_print_statistics (void);
 607 #endif
 608
 609 /* In tree-ssa-ccp.c  */
 610 tree fold_const_aggregate_ref (tree);
 611 tree gimple_fold_stmt_to_constant (gimple, tree (*)(tree));
 612
 613 /* In tree-ssa-dom.c  */
 614 extern void dump_dominator_optimization_stats (FILE *);
 615 extern void debug_dominator_optimization_stats (void);
 616 int loop_depth_of_name (tree);
 617 tree degenerate_phi_result (gimple);
 618 bool simple_iv_increment_p (gimple);
 619
 620 /* In tree-ssa-copy.c  */
 621 extern void propagate_value (use_operand_p, tree);
 622 extern void propagate_tree_value (tree *, tree);
 623 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 624 extern void replace_exp (use_operand_p, tree);
 625 extern bool may_propagate_copy (tree, tree);
 626 extern bool may_propagate_copy_into_stmt (gimple, tree);
 627 extern bool may_propagate_copy_into_asm (tree);
 628
 629 /* In tree-ssa-loop-ch.c  */
 630 bool do_while_loop_p (struct loop *);
 631
 632 /* Affine iv.  */
 633
 634 typedef struct
 635 {
 636   /* Iv = BASE + STEP * i.  */
 637   tree base, step;
 638
 639   /* True if this iv does not overflow.  */
 640   bool no_overflow;
 641 } affine_iv;
 642
 643 /* Description of number of iterations of a loop.  All the expressions inside
 644    the structure can be evaluated at the end of the loop's preheader
 645    (and due to ssa form, also anywhere inside the body of the loop).  */
 646
 647 struct tree_niter_desc
 648 {
 649   tree assumptions;     /* The boolean expression.  If this expression evaluates
 650                            to false, then the other fields in this structure
 651                            should not be used; there is no guarantee that they
 652                            will be correct.  */
 653   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 654                            the loop will exit in the first iteration (i.e.
 655                            its latch will not be executed), even if the niter
 656                            field says otherwise.  */
 657   tree niter;           /* The expression giving the number of iterations of
 658                            a loop (provided that assumptions == true and
 659                            may_be_zero == false), more precisely the number
 660                            of executions of the latch of the loop.  */
 661   double_int max;       /* The upper bound on the number of iterations of
 662                            the loop.  */
 663
 664   /* The simplified shape of the exit condition.  The loop exits if
 665      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 666      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 667      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 668      by loop unrolling.  */
 669   affine_iv control;
 670   tree bound;
 671   enum tree_code cmp;
 672 };
 673
 674 /* In tree-ssa-phiopt.c */
 675 bool empty_block_p (basic_block);
 676 basic_block *blocks_in_phiopt_order (void);
 677
 678 /* In tree-ssa-loop*.c  */
 679
 680 unsigned int tree_ssa_lim (void);
 681 unsigned int tree_ssa_unswitch_loops (void);
 682 unsigned int canonicalize_induction_variables (void);
 683 unsigned int tree_unroll_loops_completely (bool, bool);
 684 unsigned int tree_ssa_prefetch_arrays (void);
 685 void tree_ssa_iv_optimize (void);
 686 unsigned tree_predictive_commoning (void);
 687 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 688 bool parallelize_loops (void);
 689
 690 bool loop_only_exit_p (const struct loop *, const_edge);
 691 bool number_of_iterations_exit (struct loop *, edge,
 692                                 struct tree_niter_desc *niter, bool);
 693 tree find_loop_niter (struct loop *, edge *);
 694 tree loop_niter_by_eval (struct loop *, edge);
 695 tree find_loop_niter_by_eval (struct loop *, edge *);
 696 void estimate_numbers_of_iterations (void);
 697 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 698 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 699
 700 bool nowrap_type_p (tree);
 701 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 702 enum ev_direction scev_direction (const_tree);
 703
 704 void free_numbers_of_iterations_estimates (void);
 705 void free_numbers_of_iterations_estimates_loop (struct loop *);
 706 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 707 void verify_loop_closed_ssa (bool);
 708 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 709 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 710                 tree *, tree *);
 711 basic_block split_loop_exit_edge (edge);
 712 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 713                                      bool *);
 714 basic_block ip_end_pos (struct loop *);
 715 basic_block ip_normal_pos (struct loop *);
 716 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 717                                          unsigned int, sbitmap,
 718                                          edge, VEC (edge, heap) **,
 719                                          int);
 720 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 721 void rename_variables_in_loop (struct loop *);
 722 void rename_variables_in_bb (basic_block bb);
 723 tree expand_simple_operations (tree);
 724 void substitute_in_loop_info (struct loop *, tree, tree);
 725 edge single_dom_exit (struct loop *);
 726 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 727                         struct tree_niter_desc *niter);
 728 void tree_unroll_loop (struct loop *, unsigned,
 729                        edge, struct tree_niter_desc *);
 730 typedef void (*transform_callback)(struct loop *, void *);
 731 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 732                                      edge, struct tree_niter_desc *,
 733                                      transform_callback, void *);
 734 bool contains_abnormal_ssa_name_p (tree);
 735 bool stmt_dominates_stmt_p (gimple, gimple);
 736 void mark_virtual_ops_for_renaming (gimple);
 737
 738 /* In tree-ssa-dce.c */
 739 void mark_virtual_operand_for_renaming (tree);
 740 void mark_virtual_phi_result_for_renaming (gimple);
 741
 742 /* In tree-ssa-threadedge.c */
 743 extern void threadedge_initialize_values (void);
 744 extern void threadedge_finalize_values (void);
 745 extern VEC(tree,heap) *ssa_name_values;
 746 #define SSA_NAME_VALUE(x) \
 747     (SSA_NAME_VERSION(x) < VEC_length(tree, ssa_name_values) \
 748      ? VEC_index(tree, ssa_name_values, SSA_NAME_VERSION(x)) \
 749      : NULL_TREE)
 750 extern void set_ssa_name_value (tree, tree);
 751 extern bool potentially_threadable_block (basic_block);
 752 extern void thread_across_edge (gimple, edge, bool,
 753                                 VEC(tree, heap) **, tree (*) (gimple, gimple));
 754
 755 /* In tree-ssa-loop-im.c  */
 756 /* The possibilities of statement movement.  */
 757
 758 enum move_pos
 759   {
 760     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 761     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 762                                    become executed -- memory accesses, ... */
 763     MOVE_POSSIBLE               /* Unlimited movement.  */
 764   };
 765 extern enum move_pos movement_possibility (gimple);
 766 char *get_lsm_tmp_name (tree, unsigned);
 767
 768 /* In tree-flow-inline.h  */
 769 static inline void set_is_used (tree);
 770 static inline bool unmodifiable_var_p (const_tree);
 771 static inline bool ref_contains_array_ref (const_tree);
 772
 773 /* In tree-eh.c  */
 774 extern void make_eh_edges (gimple);
 775 extern bool make_eh_dispatch_edges (gimple);
 776 extern edge redirect_eh_edge (edge, basic_block);
 777 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 778 extern bool tree_could_trap_p (tree);
 779 extern bool operation_could_trap_helper_p (enum tree_code, bool, bool, bool,
 780                                            bool, tree, bool *);
 781 extern bool operation_could_trap_p (enum tree_code, bool, bool, tree);
 782 extern bool stmt_could_throw_p (gimple);
 783 extern bool tree_could_throw_p (tree);
 784 extern bool stmt_can_throw_internal (gimple);
 785 extern bool stmt_can_throw_external (gimple);
 786 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 787 extern void add_stmt_to_eh_lp (gimple, int);
 788 extern bool remove_stmt_from_eh_lp (gimple);
 789 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 790 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 791 extern int lookup_stmt_eh_lp (gimple);
 792 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 793 extern bool maybe_clean_eh_stmt (gimple);
 794 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 795 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 796                                         struct function *, gimple,
 797                                         struct pointer_map_t *, int);
 798 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 799 extern bool verify_eh_edges (gimple);
 800 extern bool verify_eh_dispatch_edge (gimple);
 801 extern void maybe_remove_unreachable_handlers (void);
 802
 803 /* In tree-ssa-pre.c  */
 804 void debug_value_expressions (unsigned int);
 805
 806 /* In tree-loop-linear.c  */
 807 extern void linear_transform_loops (void);
 808 extern unsigned perfect_loop_nest_depth (struct loop *);
 809
 810 /* In graphite.c  */
 811 extern void graphite_transform_loops (void);
 812
 813 /* In tree-data-ref.c  */
 814 extern void tree_check_data_deps (void);
 815
 816 /* In tree-ssa-loop-ivopts.c  */
 817 bool expr_invariant_in_loop_p (struct loop *, tree);
 818 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 819 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 820                                       addr_space_t);
 821 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode, bool);
 822 bool may_be_nonaddressable_p (tree expr);
 823
 824 /* In tree-ssa-threadupdate.c.  */
 825 extern bool thread_through_all_blocks (bool);
 826 extern void register_jump_thread (edge, edge, edge);
 827
 828 /* In gimplify.c  */
 829 tree force_gimple_operand_1 (tree, gimple_seq *, gimple_predicate, tree);
 830 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 831 tree force_gimple_operand_gsi_1 (gimple_stmt_iterator *, tree,
 832                                  gimple_predicate, tree,
 833                                  bool, enum gsi_iterator_update);
 834 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 835                                bool, enum gsi_iterator_update);
 836 tree gimple_fold_indirect_ref (tree);
 837
 838 /* In tree-ssa-live.c */
 839 extern void remove_unused_locals (void);
 840 extern void dump_scope_blocks (FILE *, int);
 841 extern void debug_scope_blocks (int);
 842 extern void debug_scope_block (tree, int);
 843
 844 /* In tree-ssa-address.c  */
 845
 846 /* Description of a memory address.  */
 847
 848 struct mem_address
 849 {
 850   tree symbol, base, index, step, offset;
 851 };
 852
 853 struct affine_tree_combination;
 854 tree create_mem_ref (gimple_stmt_iterator *, tree,
 855                      struct affine_tree_combination *, tree, tree, tree, bool);
 856 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 857 void get_address_description (tree, struct mem_address *);
 858 tree maybe_fold_tmr (tree);
 859
 860 unsigned int execute_fixup_cfg (void);
 861 bool fixup_noreturn_call (gimple stmt);
 862
 863 /* In ipa-pure-const.c  */
 864 void warn_function_noreturn (tree);
 865
 866 /* In tree-ssa-ter.c  */
 867 bool stmt_is_replaceable_p (gimple);
 868
 869 #include "tree-flow-inline.h"
 870
 871 void swap_tree_operands (gimple, tree *, tree *);
 872
 873 #endif /* _TREE_FLOW_H  */