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_stmt (gimple);
 432 extern void group_case_labels (void);
 433 extern gimple first_stmt (basic_block);
 434 extern gimple last_stmt (basic_block);
 435 extern gimple last_and_only_stmt (basic_block);
 436 extern edge find_taken_edge (basic_block, tree);
 437 extern basic_block label_to_block_fn (struct function *, tree);
 438 #define label_to_block(t) (label_to_block_fn (cfun, t))
 439 extern void notice_special_calls (gimple);
 440 extern void clear_special_calls (void);
 441 extern void verify_gimple_in_seq (gimple_seq);
 442 extern void verify_gimple_in_cfg (struct function *);
 443 extern tree gimple_block_label (basic_block);
 444 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 445 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 446                                         basic_block *);
 447 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 448                                       basic_block *);
 449 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 450                                           VEC(basic_block,heap) **bbs_p);
 451 extern void add_phi_args_after_copy_bb (basic_block);
 452 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 453 extern bool gimple_purge_dead_eh_edges (basic_block);
 454 extern bool gimple_purge_all_dead_eh_edges (const_bitmap);
 455 extern bool gimple_purge_dead_abnormal_call_edges (basic_block);
 456 extern bool gimple_purge_all_dead_abnormal_call_edges (const_bitmap);
 457 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code,
 458                              tree, tree);
 459 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code,
 460                              tree, tree, tree);
 461 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code,
 462                              tree, tree, tree, tree);
 463 extern void init_empty_tree_cfg (void);
 464 extern void init_empty_tree_cfg_for_function (struct function *);
 465 extern void fold_cond_expr_cond (void);
 466 extern void make_abnormal_goto_edges (basic_block, bool);
 467 extern void replace_uses_by (tree, tree);
 468 extern void start_recording_case_labels (void);
 469 extern void end_recording_case_labels (void);
 470 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 471                                            basic_block, tree);
 472 void remove_edge_and_dominated_blocks (edge);
 473 bool tree_node_can_be_shared (tree);
 474
 475 /* In tree-cfgcleanup.c  */
 476 extern bitmap cfgcleanup_altered_bbs;
 477 extern bool cleanup_tree_cfg (void);
 478
 479 /* In tree-pretty-print.c.  */
 480 extern void dump_generic_bb (FILE *, basic_block, int, int);
 481 extern int op_code_prio (enum tree_code);
 482 extern int op_prio (const_tree);
 483 extern const char *op_symbol_code (enum tree_code);
 484
 485 /* In tree-dfa.c  */
 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 bool add_referenced_var_1 (tree, struct function *);
 495 #define add_referenced_var(v) add_referenced_var_1 ((v), cfun)
 496 extern void remove_referenced_var (tree);
 497 extern tree make_rename_temp (tree, const char *);
 498 extern void set_default_def (tree, tree);
 499 extern tree gimple_default_def (struct function *, tree);
 500 extern bool stmt_references_abnormal_ssa_name (gimple);
 501 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
 502                                      HOST_WIDE_INT *, HOST_WIDE_INT *);
 503 extern tree get_addr_base_and_unit_offset (tree, HOST_WIDE_INT *);
 504 extern void find_referenced_vars_in (gimple);
 505
 506 /* In tree-phinodes.c  */
 507 extern void reserve_phi_args_for_new_edge (basic_block);
 508 extern void add_phi_node_to_bb (gimple phi, basic_block bb);
 509 extern gimple create_phi_node (tree, basic_block);
 510 extern void add_phi_arg (gimple, tree, edge, source_location, tree);
 511 extern void remove_phi_args (edge);
 512 extern void remove_phi_node (gimple_stmt_iterator *, bool);
 513 extern void remove_phi_nodes (basic_block);
 514 extern void release_phi_node (gimple);
 515 #ifdef GATHER_STATISTICS
 516 extern void phinodes_print_statistics (void);
 517 #endif
 518
 519 /* In gimple-low.c  */
 520 extern void record_vars_into (tree, tree);
 521 extern void record_vars (tree);
 522 extern bool gimple_seq_may_fallthru (gimple_seq);
 523 extern bool gimple_stmt_may_fallthru (gimple);
 524 extern bool gimple_check_call_matching_types (gimple, tree);
 525
 526
 527 /* In tree-ssa.c  */
 528
 529 /* Mapping for redirected edges.  */
 530 struct _edge_var_map {
 531   tree result;                  /* PHI result.  */
 532   tree def;                     /* PHI arg definition.  */
 533   source_location locus;        /* PHI arg location.  */
 534   tree block;                   /* PHI arg block.  */
 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, tree);
 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 void release_ssa_name_after_update_ssa (tree);
 580 void compute_global_livein (bitmap, bitmap);
 581 void mark_sym_for_renaming (tree);
 582 void mark_set_for_renaming (bitmap);
 583 bool symbol_marked_for_renaming (tree);
 584 tree get_current_def (tree);
 585 void set_current_def (tree, tree);
 586
 587 /* In tree-ssanames.c  */
 588 extern void init_ssanames (struct function *, int);
 589 extern void fini_ssanames (void);
 590 extern tree make_ssa_name_fn (struct function *, tree, gimple);
 591 extern tree duplicate_ssa_name (tree, gimple);
 592 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 593 extern void release_ssa_name (tree);
 594 extern void release_defs (gimple);
 595 extern void replace_ssa_name_symbol (tree, tree);
 596 extern bool get_ptr_info_alignment (struct ptr_info_def *, unsigned int *,
 597                                     unsigned int *);
 598 extern void mark_ptr_info_alignment_unknown (struct ptr_info_def *);
 599 extern void set_ptr_info_alignment (struct ptr_info_def *, unsigned int,
 600                                     unsigned int);
 601 extern void adjust_ptr_info_misalignment (struct ptr_info_def *,
 602                                           unsigned int);
 603
 604 #ifdef GATHER_STATISTICS
 605 extern void ssanames_print_statistics (void);
 606 #endif
 607
 608 /* In tree-ssa-ccp.c  */
 609 tree fold_const_aggregate_ref (tree);
 610 tree gimple_fold_stmt_to_constant (gimple, tree (*)(tree));
 611
 612 /* In tree-ssa-dom.c  */
 613 extern void dump_dominator_optimization_stats (FILE *);
 614 extern void debug_dominator_optimization_stats (void);
 615 int loop_depth_of_name (tree);
 616 tree degenerate_phi_result (gimple);
 617 bool simple_iv_increment_p (gimple);
 618
 619 /* In tree-ssa-copy.c  */
 620 extern void propagate_value (use_operand_p, tree);
 621 extern void propagate_tree_value (tree *, tree);
 622 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree);
 623 extern void replace_exp (use_operand_p, tree);
 624 extern bool may_propagate_copy (tree, tree);
 625 extern bool may_propagate_copy_into_stmt (gimple, tree);
 626 extern bool may_propagate_copy_into_asm (tree);
 627
 628 /* In tree-ssa-loop-ch.c  */
 629 bool do_while_loop_p (struct loop *);
 630
 631 /* Affine iv.  */
 632
 633 typedef struct
 634 {
 635   /* Iv = BASE + STEP * i.  */
 636   tree base, step;
 637
 638   /* True if this iv does not overflow.  */
 639   bool no_overflow;
 640 } affine_iv;
 641
 642 /* Description of number of iterations of a loop.  All the expressions inside
 643    the structure can be evaluated at the end of the loop's preheader
 644    (and due to ssa form, also anywhere inside the body of the loop).  */
 645
 646 struct tree_niter_desc
 647 {
 648   tree assumptions;     /* The boolean expression.  If this expression evaluates
 649                            to false, then the other fields in this structure
 650                            should not be used; there is no guarantee that they
 651                            will be correct.  */
 652   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 653                            the loop will exit in the first iteration (i.e.
 654                            its latch will not be executed), even if the niter
 655                            field says otherwise.  */
 656   tree niter;           /* The expression giving the number of iterations of
 657                            a loop (provided that assumptions == true and
 658                            may_be_zero == false), more precisely the number
 659                            of executions of the latch of the loop.  */
 660   double_int max;       /* The upper bound on the number of iterations of
 661                            the loop.  */
 662
 663   /* The simplified shape of the exit condition.  The loop exits if
 664      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
 665      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
 666      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
 667      by loop unrolling.  */
 668   affine_iv control;
 669   tree bound;
 670   enum tree_code cmp;
 671 };
 672
 673 /* In tree-ssa-phiopt.c */
 674 bool empty_block_p (basic_block);
 675 basic_block *blocks_in_phiopt_order (void);
 676
 677 /* In tree-ssa-loop*.c  */
 678
 679 unsigned int tree_ssa_lim (void);
 680 unsigned int tree_ssa_unswitch_loops (void);
 681 unsigned int canonicalize_induction_variables (void);
 682 unsigned int tree_unroll_loops_completely (bool, bool);
 683 unsigned int tree_ssa_prefetch_arrays (void);
 684 void tree_ssa_iv_optimize (void);
 685 unsigned tree_predictive_commoning (void);
 686 tree canonicalize_loop_ivs (struct loop *, tree *, bool);
 687 bool parallelize_loops (void);
 688
 689 bool loop_only_exit_p (const struct loop *, const_edge);
 690 bool number_of_iterations_exit (struct loop *, edge,
 691                                 struct tree_niter_desc *niter, bool);
 692 tree find_loop_niter (struct loop *, edge *);
 693 tree loop_niter_by_eval (struct loop *, edge);
 694 tree find_loop_niter_by_eval (struct loop *, edge *);
 695 void estimate_numbers_of_iterations (void);
 696 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool);
 697 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool);
 698
 699 bool nowrap_type_p (tree);
 700 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
 701 enum ev_direction scev_direction (const_tree);
 702
 703 void free_numbers_of_iterations_estimates (void);
 704 void free_numbers_of_iterations_estimates_loop (struct loop *);
 705 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
 706 void verify_loop_closed_ssa (bool);
 707 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
 708 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool,
 709                 tree *, tree *);
 710 basic_block split_loop_exit_edge (edge);
 711 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *,
 712                                      bool *);
 713 basic_block ip_end_pos (struct loop *);
 714 basic_block ip_normal_pos (struct loop *);
 715 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge,
 716                                          unsigned int, sbitmap,
 717                                          edge, VEC (edge, heap) **,
 718                                          int);
 719 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
 720 void rename_variables_in_loop (struct loop *);
 721 void rename_variables_in_bb (basic_block bb);
 722 tree expand_simple_operations (tree);
 723 void substitute_in_loop_info (struct loop *, tree, tree);
 724 edge single_dom_exit (struct loop *);
 725 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
 726                         struct tree_niter_desc *niter);
 727 void tree_unroll_loop (struct loop *, unsigned,
 728                        edge, struct tree_niter_desc *);
 729 typedef void (*transform_callback)(struct loop *, void *);
 730 void tree_transform_and_unroll_loop (struct loop *, unsigned,
 731                                      edge, struct tree_niter_desc *,
 732                                      transform_callback, void *);
 733 bool contains_abnormal_ssa_name_p (tree);
 734 bool stmt_dominates_stmt_p (gimple, gimple);
 735 void mark_virtual_ops_for_renaming (gimple);
 736
 737 /* In tree-ssa-dce.c */
 738 void mark_virtual_operand_for_renaming (tree);
 739 void mark_virtual_phi_result_for_renaming (gimple);
 740
 741 /* In tree-ssa-threadedge.c */
 742 extern void threadedge_initialize_values (void);
 743 extern void threadedge_finalize_values (void);
 744 extern VEC(tree,heap) *ssa_name_values;
 745 #define SSA_NAME_VALUE(x) \
 746     (SSA_NAME_VERSION(x) < VEC_length(tree, ssa_name_values) \
 747      ? VEC_index(tree, ssa_name_values, SSA_NAME_VERSION(x)) \
 748      : NULL_TREE)
 749 extern void set_ssa_name_value (tree, tree);
 750 extern bool potentially_threadable_block (basic_block);
 751 extern void thread_across_edge (gimple, edge, bool,
 752                                 VEC(tree, heap) **, tree (*) (gimple, gimple));
 753
 754 /* In tree-ssa-loop-im.c  */
 755 /* The possibilities of statement movement.  */
 756
 757 enum move_pos
 758   {
 759     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
 760     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
 761                                    become executed -- memory accesses, ... */
 762     MOVE_POSSIBLE               /* Unlimited movement.  */
 763   };
 764 extern enum move_pos movement_possibility (gimple);
 765 char *get_lsm_tmp_name (tree, unsigned);
 766
 767 /* In tree-flow-inline.h  */
 768 static inline void set_is_used (tree);
 769 static inline bool unmodifiable_var_p (const_tree);
 770 static inline bool ref_contains_array_ref (const_tree);
 771
 772 /* In tree-eh.c  */
 773 extern void make_eh_edges (gimple);
 774 extern bool make_eh_dispatch_edges (gimple);
 775 extern edge redirect_eh_edge (edge, basic_block);
 776 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block);
 777 extern bool stmt_could_throw_p (gimple);
 778 extern bool stmt_can_throw_internal (gimple);
 779 extern bool stmt_can_throw_external (gimple);
 780 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int);
 781 extern void add_stmt_to_eh_lp (gimple, int);
 782 extern bool remove_stmt_from_eh_lp (gimple);
 783 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple);
 784 extern int lookup_stmt_eh_lp_fn (struct function *, gimple);
 785 extern int lookup_stmt_eh_lp (gimple);
 786 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple);
 787 extern bool maybe_clean_eh_stmt (gimple);
 788 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple);
 789 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple,
 790                                         struct function *, gimple,
 791                                         struct pointer_map_t *, int);
 792 extern bool maybe_duplicate_eh_stmt (gimple, gimple);
 793 extern bool verify_eh_edges (gimple);
 794 extern bool verify_eh_dispatch_edge (gimple);
 795 extern void maybe_remove_unreachable_handlers (void);
 796
 797 /* In tree-ssa-pre.c  */
 798 void debug_value_expressions (unsigned int);
 799
 800 /* In tree-loop-linear.c  */
 801 extern void linear_transform_loops (void);
 802 extern unsigned perfect_loop_nest_depth (struct loop *);
 803
 804 /* In graphite.c  */
 805 extern void graphite_transform_loops (void);
 806
 807 /* In tree-data-ref.c  */
 808 extern void tree_check_data_deps (void);
 809
 810 /* In tree-ssa-loop-ivopts.c  */
 811 bool expr_invariant_in_loop_p (struct loop *, tree);
 812 bool stmt_invariant_in_loop_p (struct loop *, gimple);
 813 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode,
 814                                       addr_space_t);
 815 void initialize_costs (void);
 816 void finalize_costs (void);
 817 unsigned multiply_by_const_cost (HOST_WIDE_INT, enum machine_mode, bool);
 818 unsigned add_regs_cost (enum machine_mode, bool);
 819 unsigned multiply_regs_cost (enum machine_mode, bool);
 820 unsigned add_const_cost (enum machine_mode, bool);
 821 unsigned extend_or_trunc_reg_cost (tree, tree, bool);
 822 unsigned negate_reg_cost (enum machine_mode, bool);
 823 bool may_be_nonaddressable_p (tree expr);
 824
 825 /* In tree-ssa-threadupdate.c.  */
 826 extern bool thread_through_all_blocks (bool);
 827 extern void register_jump_thread (edge, edge, edge);
 828
 829 /* In gimplify.c  */
 830 tree force_gimple_operand_1 (tree, gimple_seq *, gimple_predicate, tree);
 831 tree force_gimple_operand (tree, gimple_seq *, bool, tree);
 832 tree force_gimple_operand_gsi_1 (gimple_stmt_iterator *, tree,
 833                                  gimple_predicate, tree,
 834                                  bool, enum gsi_iterator_update);
 835 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree,
 836                                bool, enum gsi_iterator_update);
 837 tree gimple_fold_indirect_ref (tree);
 838
 839 /* In tree-ssa-live.c */
 840 extern void remove_unused_locals (void);
 841 extern void dump_scope_blocks (FILE *, int);
 842 extern void debug_scope_blocks (int);
 843 extern void debug_scope_block (tree, int);
 844
 845 /* In tree-ssa-address.c  */
 846
 847 /* Description of a memory address.  */
 848
 849 struct mem_address
 850 {
 851   tree symbol, base, index, step, offset;
 852 };
 853
 854 struct affine_tree_combination;
 855 tree create_mem_ref (gimple_stmt_iterator *, tree,
 856                      struct affine_tree_combination *, tree, tree, tree, bool);
 857 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool);
 858 void get_address_description (tree, struct mem_address *);
 859 tree maybe_fold_tmr (tree);
 860
 861 unsigned int execute_fixup_cfg (void);
 862 bool fixup_noreturn_call (gimple stmt);
 863
 864 /* In ipa-pure-const.c  */
 865 void warn_function_noreturn (tree);
 866
 867 /* In tree-ssa-ter.c  */
 868 bool stmt_is_replaceable_p (gimple);
 869
 870 /* In tree-parloops.c  */
 871 bool parallelized_function_p (tree);
 872
 873 #include "tree-flow-inline.h"
 874
 875 void swap_tree_operands (gimple, tree *, tree *);
 876
 877 #endif /* _TREE_FLOW_H  */