gcc/tree-flow.h

   1 /* Data and Control Flow Analysis for Trees.
   2    Copyright (C) 2001, 2003, 2004, 2005, 2006, 2007
   3    Free Software Foundation, Inc.
   4    Contributed by Diego Novillo <dnovillo@redhat.com>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 3, or (at your option)
  11 any later version.
  12
  13 GCC is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #ifndef _TREE_FLOW_H
  23 #define _TREE_FLOW_H 1
  24
  25 #include "bitmap.h"
  26 #include "hard-reg-set.h"
  27 #include "basic-block.h"
  28 #include "hashtab.h"
  29 #include "tree-gimple.h"
  30 #include "tree-ssa-operands.h"
  31 #include "cgraph.h"
  32 #include "ipa-reference.h"
  33
  34 /* Forward declare structures for the garbage collector GTY markers.  */
  35 #ifndef GCC_BASIC_BLOCK_H
  36 struct edge_def;
  37 typedef struct edge_def *edge;
  38 struct basic_block_def;
  39 typedef struct basic_block_def *basic_block;
  40 #endif
  41 struct static_var_ann_d;
  42
  43 /* The reasons a variable may escape a function.  */
  44 enum escape_type
  45 {
  46   NO_ESCAPE = 0,                        /* Doesn't escape.  */
  47   ESCAPE_STORED_IN_GLOBAL = 1 << 0,
  48   ESCAPE_TO_ASM = 1 << 1,               /* Passed by address to an assembly
  49                                            statement.  */
  50   ESCAPE_TO_CALL = 1 << 2,              /* Escapes to a function call.  */
  51   ESCAPE_BAD_CAST = 1 << 3,             /* Cast from pointer to integer */
  52   ESCAPE_TO_RETURN = 1 << 4,            /* Returned from function.  */
  53   ESCAPE_TO_PURE_CONST = 1 << 5,        /* Escapes to a pure or constant
  54                                            function call.  */
  55   ESCAPE_IS_GLOBAL = 1 << 6,            /* Is a global variable.  */
  56   ESCAPE_IS_PARM = 1 << 7,              /* Is an incoming function argument.  */
  57   ESCAPE_UNKNOWN = 1 << 8               /* We believe it escapes for
  58                                            some reason not enumerated
  59                                            above.  */
  60 };
  61
  62 /* Memory reference statistics for individual memory symbols,
  63    collected during alias analysis.  */
  64 struct mem_sym_stats_d GTY(())
  65 {
  66   /* Memory symbol.  */
  67   tree var;
  68
  69   /* Nonzero if this entry has been assigned a partition.  */
  70   unsigned int partitioned_p : 1;
  71
  72   /* Nonzero if VAR is a memory partition tag that already contains
  73      call-clobbered variables in its partition set.  */
  74   unsigned int has_call_clobbered_vars : 1;
  75
  76   /* Number of direct reference sites.  A direct reference to VAR is any
  77      reference of the form 'VAR = ' or ' = VAR'.  For GIMPLE reg
  78      pointers, this is the number of sites where the pointer is
  79      dereferenced.  */
  80   long num_direct_writes;
  81   long num_direct_reads;
  82
  83   /* Number of indirect reference sites.  An indirect reference to VAR
  84      is any reference via a pointer that contains VAR in its points-to
  85      set or, in the case of call-clobbered symbols, a function call.  */
  86   long num_indirect_writes;
  87   long num_indirect_reads;
  88
  89   /* Execution frequency.  This is the sum of the execution
  90      frequencies of all the statements that reference this object
  91      weighted by the number of references in each statement.  This is
  92      the main key used to sort the list of symbols to partition.
  93      Symbols with high execution frequencies are put at the bottom of
  94      the work list (ie, they are partitioned last).
  95      Execution frequencies are taken directly from each basic block,
  96      so compiling with PGO enabled will increase the precision of this
  97      estimate.  */
  98   long frequency_reads;
  99   long frequency_writes;
 100
 101   /* Set of memory tags that contain VAR in their alias set.  */
 102   bitmap parent_tags;
 103 };
 104
 105 typedef struct mem_sym_stats_d *mem_sym_stats_t;
 106 DEF_VEC_P(mem_sym_stats_t);
 107 DEF_VEC_ALLOC_P(mem_sym_stats_t, heap);
 108
 109 /* Memory reference statistics collected during alias analysis.  */
 110 struct mem_ref_stats_d GTY(())
 111 {
 112   /* Number of statements that make memory references.  */
 113   long num_mem_stmts;
 114
 115   /* Number of statements that make function calls.  */
 116   long num_call_sites;
 117
 118   /* Number of statements that make calls to pure/const functions.  */
 119   long num_pure_const_call_sites;
 120
 121   /* Number of ASM statements.  */
 122   long num_asm_sites;
 123
 124   /* Estimated number of virtual operands needed as computed by
 125    compute_memory_partitions.  */
 126   long num_vuses;
 127   long num_vdefs;
 128
 129   /* This maps every symbol used to make "memory" references
 130      (pointers, arrays, structures, etc) to an instance of struct
 131      mem_sym_stats_d describing reference statistics for the symbol.  */
 132   struct pointer_map_t * GTY((skip)) mem_sym_stats;
 133 };
 134
 135
 136 /* Gimple dataflow datastructure. All publicly available fields shall have
 137    gimple_ accessor defined in tree-flow-inline.h, all publicly modifiable
 138    fields should have gimple_set accessor.  */
 139 struct gimple_df GTY(())
 140 {
 141   /* Array of all variables referenced in the function.  */
 142   htab_t GTY((param_is (union tree_node))) referenced_vars;
 143
 144   /* A list of all the noreturn calls passed to modify_stmt.
 145      cleanup_control_flow uses it to detect cases where a mid-block
 146      indirect call has been turned into a noreturn call.  When this
 147      happens, all the instructions after the call are no longer
 148      reachable and must be deleted as dead.  */
 149   VEC(tree,gc) *modified_noreturn_calls;
 150
 151   /* Array of all SSA_NAMEs used in the function.  */
 152   VEC(tree,gc) *ssa_names;
 153
 154   /* Artificial variable used to model the effects of function calls.  */
 155   tree global_var;
 156
 157   /* Artificial variable used to model the effects of nonlocal
 158      variables.  */
 159   tree nonlocal_all;
 160
 161   /* Call clobbered variables in the function.  If bit I is set, then
 162      REFERENCED_VARS (I) is call-clobbered.  */
 163   bitmap call_clobbered_vars;
 164
 165   /* Addressable variables in the function.  If bit I is set, then
 166      REFERENCED_VARS (I) has had its address taken.  Note that
 167      CALL_CLOBBERED_VARS and ADDRESSABLE_VARS are not related.  An
 168      addressable variable is not necessarily call-clobbered (e.g., a
 169      local addressable whose address does not escape) and not all
 170      call-clobbered variables are addressable (e.g., a local static
 171      variable).  */
 172   bitmap addressable_vars;
 173
 174   /* Free list of SSA_NAMEs.  */
 175   tree free_ssanames;
 176
 177   /* Hashtable holding definition for symbol.  If this field is not NULL, it
 178      means that the first reference to this variable in the function is a
 179      USE or a VUSE.  In those cases, the SSA renamer creates an SSA name
 180      for this variable with an empty defining statement.  */
 181   htab_t GTY((param_is (union tree_node))) default_defs;
 182
 183   /* 'true' after aliases have been computed (see compute_may_aliases).  */
 184   unsigned int aliases_computed_p : 1;
 185
 186   /* True if the code is in ssa form.  */
 187   unsigned int in_ssa_p : 1;
 188
 189   struct ssa_operands ssa_operands;
 190
 191   /* Hashtable of variables annotations.  Used for static variables only;
 192      local variables have direct pointer in the tree node.  */
 193   htab_t GTY((param_is (struct static_var_ann_d))) var_anns;
 194
 195   /* Memory reference statistics collected during alias analysis.
 196      This information is used to drive the memory partitioning
 197      heuristics in compute_memory_partitions.  */
 198   struct mem_ref_stats_d mem_ref_stats;
 199 };
 200
 201 /* Accessors for internal use only.  Generic code should use abstraction
 202    provided by tree-flow-inline.h or specific modules.  */
 203 #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames
 204 #define SSANAMES(fun) (fun)->gimple_df->ssa_names
 205 #define MODIFIED_NORETURN_CALLS(fun) (fun)->gimple_df->modified_noreturn_calls
 206 #define DEFAULT_DEFS(fun) (fun)->gimple_df->default_defs
 207
 208 typedef struct
 209 {
 210   htab_t htab;
 211   PTR *slot;
 212   PTR *limit;
 213 } htab_iterator;
 214
 215 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
 216    storing each element in RESULT, which is of type TYPE.  */
 217 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
 218   for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
 219         !end_htab_p (&(ITER)); \
 220         RESULT = (TYPE) next_htab_element (&(ITER)))
 221
 222 /*---------------------------------------------------------------------------
 223                       Attributes for SSA_NAMEs.
 224
 225   NOTE: These structures are stored in struct tree_ssa_name
 226   but are only used by the tree optimizers, so it makes better sense
 227   to declare them here to avoid recompiling unrelated files when
 228   making changes.
 229 ---------------------------------------------------------------------------*/
 230
 231 /* Aliasing information for SSA_NAMEs representing pointer variables.  */
 232 struct ptr_info_def GTY(())
 233 {
 234   /* Nonzero if points-to analysis couldn't determine where this pointer
 235      is pointing to.  */
 236   unsigned int pt_anything : 1;
 237
 238   /* Nonzero if the value of this pointer escapes the current function.  */
 239   unsigned int value_escapes_p : 1;
 240
 241   /* Nonzero if this pointer is dereferenced.  */
 242   unsigned int is_dereferenced : 1;
 243
 244   /* Nonzero if this pointer points to a global variable.  */
 245   unsigned int pt_global_mem : 1;
 246
 247   /* Nonzero if this pointer points to NULL.  */
 248   unsigned int pt_null : 1;
 249
 250   /* Mask of reasons this pointer's value escapes the function  */
 251   ENUM_BITFIELD (escape_type) escape_mask : 9;
 252
 253   /* Set of variables that this pointer may point to.  */
 254   bitmap pt_vars;
 255
 256   /* If this pointer has been dereferenced, and points-to information is
 257      more precise than type-based aliasing, indirect references to this
 258      pointer will be represented by this memory tag, instead of the type
 259      tag computed by TBAA.  */
 260   tree name_mem_tag;
 261 };
 262
 263
 264 /*---------------------------------------------------------------------------
 265                    Tree annotations stored in tree_base.ann
 266 ---------------------------------------------------------------------------*/
 267 enum tree_ann_type { TREE_ANN_COMMON, VAR_ANN, FUNCTION_ANN, STMT_ANN };
 268
 269 struct tree_ann_common_d GTY(())
 270 {
 271   /* Annotation type.  */
 272   enum tree_ann_type type;
 273
 274  /* Auxiliary info specific to a pass.  At all times, this
 275     should either point to valid data or be NULL.  */
 276   PTR GTY ((skip (""))) aux;
 277
 278   /* The value handle for this expression.  Used by GVN-PRE.  */
 279   tree GTY((skip)) value_handle;
 280 };
 281
 282 /* It is advantageous to avoid things like life analysis for variables which
 283    do not need PHI nodes.  This enum describes whether or not a particular
 284    variable may need a PHI node.  */
 285
 286 enum need_phi_state {
 287   /* This is the default.  If we are still in this state after finding
 288      all the definition and use sites, then we will assume the variable
 289      needs PHI nodes.  This is probably an overly conservative assumption.  */
 290   NEED_PHI_STATE_UNKNOWN,
 291
 292   /* This state indicates that we have seen one or more sets of the
 293      variable in a single basic block and that the sets dominate all
 294      uses seen so far.  If after finding all definition and use sites
 295      we are still in this state, then the variable does not need any
 296      PHI nodes.  */
 297   NEED_PHI_STATE_NO,
 298
 299   /* This state indicates that we have either seen multiple definitions of
 300      the variable in multiple blocks, or that we encountered a use in a
 301      block that was not dominated by the block containing the set(s) of
 302      this variable.  This variable is assumed to need PHI nodes.  */
 303   NEED_PHI_STATE_MAYBE
 304 };
 305
 306
 307 /* The "no alias" attribute allows alias analysis to make more
 308    aggressive assumptions when assigning alias sets, computing
 309    points-to information and memory partitions.  These attributes
 310    are the result of user annotations or flags (e.g.,
 311    -fargument-noalias).  */
 312 enum noalias_state {
 313     /* Default state.  No special assumptions can be made about this
 314        symbol.  */
 315     MAY_ALIAS = 0,
 316
 317     /* The symbol does not alias with other symbols that have a
 318        NO_ALIAS* attribute.  */
 319     NO_ALIAS,
 320
 321     /* The symbol does not alias with other symbols that have a
 322        NO_ALIAS*, and it may not alias with global symbols.  */
 323     NO_ALIAS_GLOBAL,
 324
 325     /* The symbol does not alias with any other symbols.  */
 326     NO_ALIAS_ANYTHING
 327 };
 328
 329
 330 struct var_ann_d GTY(())
 331 {
 332   struct tree_ann_common_d common;
 333
 334   /* Used by the out of SSA pass to determine whether this variable has
 335      been seen yet or not.  */
 336   unsigned out_of_ssa_tag : 1;
 337
 338   /* Used when building base variable structures in a var_map.  */
 339   unsigned base_var_processed : 1;
 340
 341   /* Nonzero if this variable was used after SSA optimizations were
 342      applied.  We set this when translating out of SSA form.  */
 343   unsigned used : 1;
 344
 345   /* This field indicates whether or not the variable may need PHI nodes.
 346      See the enum's definition for more detailed information about the
 347      states.  */
 348   ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
 349
 350   /* Used during operand processing to determine if this variable is already
 351      in the VUSE list.  */
 352   unsigned in_vuse_list : 1;
 353
 354   /* Used during operand processing to determine if this variable is already
 355      in the VDEF list.  */
 356   unsigned in_vdef_list : 1;
 357
 358   /* True for HEAP artificial variables.  These variables represent
 359      the memory area allocated by a call to malloc.  */
 360   unsigned is_heapvar : 1;
 361
 362   /* True if the variable is call clobbered.  */
 363   unsigned call_clobbered : 1;
 364
 365   /* This field describes several "no alias" attributes that some
 366      symbols are known to have.  See the enum's definition for more
 367      information on each attribute.  */
 368   ENUM_BITFIELD (noalias_state) noalias_state : 2;
 369
 370   /* Mask of values saying the reasons why this variable has escaped
 371      the function.  */
 372   ENUM_BITFIELD (escape_type) escape_mask : 9;
 373
 374   /* Memory partition tag assigned to this symbol.  */
 375   tree mpt;
 376
 377   /* If this variable is a pointer P that has been dereferenced, this
 378      field is an artificial variable that represents the memory
 379      location *P.  Every other pointer Q that is type-compatible with
 380      P will also have the same memory tag.  If the variable is not a
 381      pointer or if it is never dereferenced, this must be NULL.
 382      FIXME, do we really need this here?  How much slower would it be
 383      to convert to hash table?  */
 384   tree symbol_mem_tag;
 385
 386   /* Used when going out of SSA form to indicate which partition this
 387      variable represents storage for.  */
 388   unsigned partition;
 389
 390   /* Used by var_map for the base index of ssa base variables.  */
 391   unsigned base_index;
 392
 393   /* During into-ssa and the dominator optimizer, this field holds the
 394      current version of this variable (an SSA_NAME).  */
 395   tree current_def;
 396 };
 397
 398 /* Container for variable annotation used by hashtable for annotations for
 399    static variables.  */
 400 struct static_var_ann_d GTY(())
 401 {
 402   struct var_ann_d ann;
 403   unsigned int uid;
 404 };
 405
 406 struct function_ann_d GTY(())
 407 {
 408   struct tree_ann_common_d common;
 409
 410   /* Pointer to the structure that contains the sets of global
 411      variables modified by function calls.  This field is only used
 412      for FUNCTION_DECLs.  */
 413   ipa_reference_vars_info_t GTY ((skip)) reference_vars_info;
 414 };
 415
 416 typedef struct immediate_use_iterator_d
 417 {
 418   /* This is the current use the iterator is processing.  */
 419   ssa_use_operand_t *imm_use;
 420   /* This marks the last use in the list (use node from SSA_NAME)  */
 421   ssa_use_operand_t *end_p;
 422   /* This node is inserted and used to mark the end of the uses for a stmt.  */
 423   ssa_use_operand_t iter_node;
 424   /* This is the next ssa_name to visit.  IMM_USE may get removed before
 425      the next one is traversed to, so it must be cached early.  */
 426   ssa_use_operand_t *next_imm_name;
 427 } imm_use_iterator;
 428
 429
 430 /* Use this iterator when simply looking at stmts.  Adding, deleting or
 431    modifying stmts will cause this iterator to malfunction.  */
 432
 433 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR)                       \
 434   for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR));     \
 435        !end_readonly_imm_use_p (&(ITER));                       \
 436        (DEST) = next_readonly_imm_use (&(ITER)))
 437
 438 /* Use this iterator to visit each stmt which has a use of SSAVAR.  */
 439
 440 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR)               \
 441   for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR));         \
 442        !end_imm_use_stmt_p (&(ITER));                           \
 443        (STMT) = next_imm_use_stmt (&(ITER)))
 444
 445 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early.  Failure to
 446    do so will result in leaving a iterator marker node in the immediate
 447    use list, and nothing good will come from that.   */
 448 #define BREAK_FROM_IMM_USE_STMT(ITER)                           \
 449    {                                                            \
 450      end_imm_use_stmt_traverse (&(ITER));                       \
 451      break;                                                     \
 452    }
 453
 454
 455 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
 456    get access to each occurrence of ssavar on the stmt returned by
 457    that iterator..  for instance:
 458
 459      FOR_EACH_IMM_USE_STMT (stmt, iter, var)
 460        {
 461          FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 462            {
 463              SET_USE (use_p) = blah;
 464            }
 465          update_stmt (stmt);
 466        }                                                         */
 467
 468 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER)                    \
 469   for ((DEST) = first_imm_use_on_stmt (&(ITER));                \
 470        !end_imm_use_on_stmt_p (&(ITER));                        \
 471        (DEST) = next_imm_use_on_stmt (&(ITER)))
 472
 473
 474
 475 struct stmt_ann_d GTY(())
 476 {
 477   struct tree_ann_common_d common;
 478
 479   /* Basic block that contains this statement.  */
 480   basic_block bb;
 481
 482   /* Operand cache for stmt.  */
 483   struct stmt_operands_d GTY ((skip (""))) operands;
 484
 485   /* Set of variables that have had their address taken in the statement.  */
 486   bitmap addresses_taken;
 487
 488   /* Unique identifier for this statement.  These ID's are to be
 489      created by each pass on an as-needed basis in any order
 490      convenient for the pass which needs statement UIDs.  This field
 491      should only be accessed thru set_gimple_stmt_uid and
 492      gimple_stmt_uid functions.  */
 493   unsigned int uid;
 494
 495   /* Nonzero if the statement references memory (at least one of its
 496      expressions contains a non-register operand).  */
 497   unsigned references_memory : 1;
 498
 499   /* Nonzero if the statement has been modified (meaning that the operands
 500      need to be scanned again).  */
 501   unsigned modified : 1;
 502
 503   /* Nonzero if the statement makes references to volatile storage.  */
 504   unsigned has_volatile_ops : 1;
 505 };
 506
 507 union tree_ann_d GTY((desc ("ann_type ((tree_ann_t)&%h)")))
 508 {
 509   struct tree_ann_common_d GTY((tag ("TREE_ANN_COMMON"))) common;
 510   struct var_ann_d GTY((tag ("VAR_ANN"))) vdecl;
 511   struct function_ann_d GTY((tag ("FUNCTION_ANN"))) fdecl;
 512   struct stmt_ann_d GTY((tag ("STMT_ANN"))) stmt;
 513 };
 514
 515 typedef union tree_ann_d *tree_ann_t;
 516 typedef struct var_ann_d *var_ann_t;
 517 typedef struct function_ann_d *function_ann_t;
 518 typedef struct stmt_ann_d *stmt_ann_t;
 519 typedef struct tree_ann_common_d *tree_ann_common_t;
 520
 521 static inline tree_ann_common_t tree_common_ann (const_tree);
 522 static inline tree_ann_common_t get_tree_common_ann (tree);
 523 static inline var_ann_t var_ann (const_tree);
 524 static inline var_ann_t get_var_ann (tree);
 525 static inline function_ann_t function_ann (const_tree);
 526 static inline function_ann_t get_function_ann (tree);
 527 static inline stmt_ann_t stmt_ann (tree);
 528 static inline bool has_stmt_ann (tree);
 529 static inline stmt_ann_t get_stmt_ann (tree);
 530 static inline enum tree_ann_type ann_type (tree_ann_t);
 531 static inline basic_block bb_for_stmt (tree);
 532 extern void set_bb_for_stmt (tree, basic_block);
 533 static inline bool noreturn_call_p (tree);
 534 static inline void update_stmt (tree);
 535 static inline bool stmt_modified_p (tree);
 536 static inline bitmap may_aliases (const_tree);
 537 static inline int get_lineno (const_tree);
 538 static inline bitmap addresses_taken (tree);
 539
 540 /*---------------------------------------------------------------------------
 541                   Structure representing predictions in tree level.
 542 ---------------------------------------------------------------------------*/
 543 struct edge_prediction GTY((chain_next ("%h.ep_next")))
 544 {
 545   struct edge_prediction *ep_next;
 546   edge ep_edge;
 547   enum br_predictor ep_predictor;
 548   int ep_probability;
 549 };
 550
 551 /* Accessors for basic block annotations.  */
 552 static inline tree phi_nodes (const_basic_block);
 553 static inline void set_phi_nodes (basic_block, tree);
 554
 555 /*---------------------------------------------------------------------------
 556                               Global declarations
 557 ---------------------------------------------------------------------------*/
 558 struct int_tree_map GTY(())
 559 {
 560
 561   unsigned int uid;
 562   tree to;
 563 };
 564
 565 extern unsigned int int_tree_map_hash (const void *);
 566 extern int int_tree_map_eq (const void *, const void *);
 567
 568 extern unsigned int uid_decl_map_hash (const void *);
 569 extern int uid_decl_map_eq (const void *, const void *);
 570
 571 typedef struct
 572 {
 573   htab_iterator hti;
 574 } referenced_var_iterator;
 575
 576
 577 /* This macro loops over all the referenced vars, one at a time, putting the
 578    current var in VAR.  Note:  You are not allowed to add referenced variables
 579    to the hashtable while using this macro.  Doing so may cause it to behave
 580    erratically.  */
 581
 582 #define FOR_EACH_REFERENCED_VAR(VAR, ITER) \
 583   for ((VAR) = first_referenced_var (&(ITER)); \
 584        !end_referenced_vars_p (&(ITER)); \
 585        (VAR) = next_referenced_var (&(ITER)))
 586
 587
 588 typedef struct
 589 {
 590   int i;
 591 } safe_referenced_var_iterator;
 592
 593 /* This macro loops over all the referenced vars, one at a time, putting the
 594    current var in VAR.  You are allowed to add referenced variables during the
 595    execution of this macro, however, the macro will not iterate over them.  It
 596    requires a temporary vector of trees, VEC, whose lifetime is controlled by
 597    the caller.  The purpose of the vector is to temporarily store the
 598    referenced_variables hashtable so that adding referenced variables does not
 599    affect the hashtable.  */
 600
 601 #define FOR_EACH_REFERENCED_VAR_SAFE(VAR, VEC, ITER) \
 602   for ((ITER).i = 0, fill_referenced_var_vec (&(VEC)); \
 603        VEC_iterate (tree, (VEC), (ITER).i, (VAR)); \
 604        (ITER).i++)
 605
 606 extern tree referenced_var_lookup (unsigned int);
 607 extern bool referenced_var_check_and_insert (tree);
 608 #define num_referenced_vars htab_elements (gimple_referenced_vars (cfun))
 609 #define referenced_var(i) referenced_var_lookup (i)
 610
 611 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
 612 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
 613
 614 /* Macros for showing usage statistics.  */
 615 #define SCALE(x) ((unsigned long) ((x) < 1024*10        \
 616                   ? (x)                                 \
 617                   : ((x) < 1024*1024*10                 \
 618                      ? (x) / 1024                       \
 619                      : (x) / (1024*1024))))
 620
 621 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
 622
 623 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 624
 625 /*---------------------------------------------------------------------------
 626                               Block iterators
 627 ---------------------------------------------------------------------------*/
 628
 629 typedef struct {
 630   tree_stmt_iterator tsi;
 631   basic_block bb;
 632 } block_stmt_iterator;
 633
 634 static inline block_stmt_iterator bsi_start (basic_block);
 635 static inline block_stmt_iterator bsi_last (basic_block);
 636 static inline block_stmt_iterator bsi_after_labels (basic_block);
 637 block_stmt_iterator bsi_for_stmt (tree);
 638 static inline bool bsi_end_p (block_stmt_iterator);
 639 static inline void bsi_next (block_stmt_iterator *);
 640 static inline void bsi_prev (block_stmt_iterator *);
 641 static inline tree bsi_stmt (block_stmt_iterator);
 642 static inline tree * bsi_stmt_ptr (block_stmt_iterator);
 643
 644 extern void bsi_remove (block_stmt_iterator *, bool);
 645 extern void bsi_move_before (block_stmt_iterator *, block_stmt_iterator *);
 646 extern void bsi_move_after (block_stmt_iterator *, block_stmt_iterator *);
 647 extern void bsi_move_to_bb_end (block_stmt_iterator *, basic_block);
 648
 649 enum bsi_iterator_update
 650 {
 651   /* Note that these are intentionally in the same order as TSI_FOO.  They
 652      mean exactly the same as their TSI_* counterparts.  */
 653   BSI_NEW_STMT,
 654   BSI_SAME_STMT,
 655   BSI_CHAIN_START,
 656   BSI_CHAIN_END,
 657   BSI_CONTINUE_LINKING
 658 };
 659
 660 extern void bsi_insert_before (block_stmt_iterator *, tree,
 661                                enum bsi_iterator_update);
 662 extern void bsi_insert_after (block_stmt_iterator *, tree,
 663                               enum bsi_iterator_update);
 664
 665 extern void bsi_replace (const block_stmt_iterator *, tree, bool);
 666
 667 /*---------------------------------------------------------------------------
 668                               OpenMP Region Tree
 669 ---------------------------------------------------------------------------*/
 670
 671 /* Parallel region information.  Every parallel and workshare
 672    directive is enclosed between two markers, the OMP_* directive
 673    and a corresponding OMP_RETURN statement.  */
 674
 675 struct omp_region
 676 {
 677   /* The enclosing region.  */
 678   struct omp_region *outer;
 679
 680   /* First child region.  */
 681   struct omp_region *inner;
 682
 683   /* Next peer region.  */
 684   struct omp_region *next;
 685
 686   /* Block containing the omp directive as its last stmt.  */
 687   basic_block entry;
 688
 689   /* Block containing the OMP_RETURN as its last stmt.  */
 690   basic_block exit;
 691
 692   /* Block containing the OMP_CONTINUE as its last stmt.  */
 693   basic_block cont;
 694
 695   /* If this is a combined parallel+workshare region, this is a list
 696      of additional arguments needed by the combined parallel+workshare
 697      library call.  */
 698   tree ws_args;
 699
 700   /* The code for the omp directive of this region.  */
 701   enum tree_code type;
 702
 703   /* Schedule kind, only used for OMP_FOR type regions.  */
 704   enum omp_clause_schedule_kind sched_kind;
 705
 706   /* True if this is a combined parallel+workshare region.  */
 707   bool is_combined_parallel;
 708 };
 709
 710 extern struct omp_region *root_omp_region;
 711 extern struct omp_region *new_omp_region (basic_block, enum tree_code,
 712                                           struct omp_region *);
 713 extern void free_omp_regions (void);
 714 void omp_expand_local (basic_block);
 715 extern tree find_omp_clause (tree, enum tree_code);
 716 tree copy_var_decl (tree, tree, tree);
 717
 718 /*---------------------------------------------------------------------------
 719                               Function prototypes
 720 ---------------------------------------------------------------------------*/
 721 /* In tree-cfg.c  */
 722
 723 /* Location to track pending stmt for edge insertion.  */
 724 #define PENDING_STMT(e) ((e)->insns.t)
 725
 726 extern void delete_tree_cfg_annotations (void);
 727 extern bool stmt_ends_bb_p (const_tree);
 728 extern bool is_ctrl_stmt (const_tree);
 729 extern bool is_ctrl_altering_stmt (const_tree);
 730 extern bool simple_goto_p (const_tree);
 731 extern bool tree_can_make_abnormal_goto (const_tree);
 732 extern basic_block single_noncomplex_succ (basic_block bb);
 733 extern void tree_dump_bb (basic_block, FILE *, int);
 734 extern void debug_tree_bb (basic_block);
 735 extern basic_block debug_tree_bb_n (int);
 736 extern void dump_tree_cfg (FILE *, int);
 737 extern void debug_tree_cfg (int);
 738 extern void dump_cfg_stats (FILE *);
 739 extern void dot_cfg (void);
 740 extern void debug_cfg_stats (void);
 741 extern void debug_loops (int);
 742 extern void debug_loop (struct loop *, int);
 743 extern void debug_loop_num (unsigned, int);
 744 extern void print_loops (FILE *, int);
 745 extern void print_loops_bb (FILE *, basic_block, int, int);
 746 extern void cleanup_dead_labels (void);
 747 extern void group_case_labels (void);
 748 extern tree first_stmt (basic_block);
 749 extern tree last_stmt (basic_block);
 750 extern tree last_and_only_stmt (basic_block);
 751 extern edge find_taken_edge (basic_block, tree);
 752 extern basic_block label_to_block_fn (struct function *, tree);
 753 #define label_to_block(t) (label_to_block_fn (cfun, t))
 754 extern void bsi_insert_on_edge (edge, tree);
 755 extern basic_block bsi_insert_on_edge_immediate (edge, tree);
 756 extern void bsi_commit_one_edge_insert (edge, basic_block *);
 757 extern void bsi_commit_edge_inserts (void);
 758 extern void notice_special_calls (tree);
 759 extern void clear_special_calls (void);
 760 extern void verify_stmts (void);
 761 extern void verify_gimple (void);
 762 extern void verify_gimple_1 (tree);
 763 extern tree tree_block_label (basic_block);
 764 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
 765 extern bool tree_duplicate_sese_region (edge, edge, basic_block *, unsigned,
 766                                         basic_block *);
 767 extern bool tree_duplicate_sese_tail (edge, edge, basic_block *, unsigned,
 768                                       basic_block *);
 769 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit,
 770                                           VEC(basic_block,heap) **bbs_p);
 771 extern void add_phi_args_after_copy_bb (basic_block);
 772 extern void add_phi_args_after_copy (basic_block *, unsigned, edge);
 773 extern bool tree_purge_dead_abnormal_call_edges (basic_block);
 774 extern bool tree_purge_dead_eh_edges (basic_block);
 775 extern bool tree_purge_all_dead_eh_edges (const_bitmap);
 776 extern tree gimplify_val (block_stmt_iterator *, tree, tree);
 777 extern tree gimplify_build1 (block_stmt_iterator *, enum tree_code,
 778                              tree, tree);
 779 extern tree gimplify_build2 (block_stmt_iterator *, enum tree_code,
 780                              tree, tree, tree);
 781 extern tree gimplify_build3 (block_stmt_iterator *, enum tree_code,
 782                              tree, tree, tree, tree);
 783 extern void init_empty_tree_cfg (void);
 784 extern void init_empty_tree_cfg_for_function (struct function *);
 785 extern void fold_cond_expr_cond (void);
 786 extern void make_abnormal_goto_edges (basic_block, bool);
 787 extern void replace_uses_by (tree, tree);
 788 extern void start_recording_case_labels (void);
 789 extern void end_recording_case_labels (void);
 790 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
 791                                            basic_block);
 792 void remove_edge_and_dominated_blocks (edge);
 793 void mark_virtual_ops_in_bb (basic_block);
 794
 795 /* In tree-cfgcleanup.c  */
 796 extern bitmap cfgcleanup_altered_bbs;
 797 extern bool cleanup_tree_cfg (void);
 798
 799 /* In tree-pretty-print.c.  */
 800 extern void dump_generic_bb (FILE *, basic_block, int, int);
 801 extern const char *op_symbol_code (enum tree_code);
 802
 803 /* In tree-dfa.c  */
 804 extern var_ann_t create_var_ann (tree);
 805 extern function_ann_t create_function_ann (tree);
 806 extern stmt_ann_t create_stmt_ann (tree);
 807 extern void renumber_gimple_stmt_uids (void);
 808 extern tree_ann_common_t create_tree_common_ann (tree);
 809 extern void dump_dfa_stats (FILE *);
 810 extern void debug_dfa_stats (void);
 811 extern void debug_referenced_vars (void);
 812 extern void dump_referenced_vars (FILE *);
 813 extern void dump_variable (FILE *, tree);
 814 extern void debug_variable (tree);
 815 extern tree get_virtual_var (tree);
 816 extern void add_referenced_var (tree);
 817 extern void remove_referenced_var (tree);
 818 extern void mark_symbols_for_renaming (tree);
 819 extern void find_new_referenced_vars (tree *);
 820 extern tree make_rename_temp (tree, const char *);
 821 extern void set_default_def (tree, tree);
 822 extern tree gimple_default_def (struct function *, tree);
 823 extern bool stmt_references_abnormal_ssa_name (tree);
 824 extern bool refs_may_alias_p (tree, tree);
 825 extern tree get_single_def_stmt (tree);
 826 extern tree get_single_def_stmt_from_phi (tree, tree);
 827 extern tree get_single_def_stmt_with_phi (tree, tree);
 828
 829 /* In tree-phinodes.c  */
 830 extern void reserve_phi_args_for_new_edge (basic_block);
 831 extern tree create_phi_node (tree, basic_block);
 832 extern void add_phi_arg (tree, tree, edge);
 833 extern void remove_phi_args (edge);
 834 extern void remove_phi_node (tree, tree, bool);
 835 extern tree phi_reverse (tree);
 836 extern void init_phinodes (void);
 837 extern void fini_phinodes (void);
 838 extern void release_phi_node (tree);
 839 #ifdef GATHER_STATISTICS
 840 extern void phinodes_print_statistics (void);
 841 #endif
 842
 843 /* In gimple-low.c  */
 844 extern void record_vars_into (tree, tree);
 845 extern void record_vars (tree);
 846 extern bool block_may_fallthru (const_tree);
 847
 848 /* In tree-ssa-alias.c  */
 849 extern unsigned int compute_may_aliases (void);
 850 extern void dump_may_aliases_for (FILE *, tree);
 851 extern void debug_may_aliases_for (tree);
 852 extern void dump_alias_info (FILE *);
 853 extern void debug_alias_info (void);
 854 extern void dump_points_to_info (FILE *);
 855 extern void debug_points_to_info (void);
 856 extern void dump_points_to_info_for (FILE *, tree);
 857 extern void debug_points_to_info_for (tree);
 858 extern bool may_be_aliased (tree);
 859 extern struct ptr_info_def *get_ptr_info (tree);
 860 extern void new_type_alias (tree, tree, tree);
 861 extern void count_uses_and_derefs (tree, tree, unsigned *, unsigned *,
 862                                    unsigned *);
 863 static inline bool ref_contains_array_ref (const_tree);
 864 static inline bool array_ref_contains_indirect_ref (const_tree);
 865 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
 866                                      HOST_WIDE_INT *, HOST_WIDE_INT *);
 867 extern tree create_tag_raw (enum tree_code, tree, const char *);
 868 extern void delete_mem_ref_stats (struct function *);
 869 extern void dump_mem_ref_stats (FILE *);
 870 extern void debug_mem_ref_stats (void);
 871 extern void debug_memory_partitions (void);
 872 extern void debug_mem_sym_stats (tree var);
 873 extern void dump_mem_sym_stats_for_var (FILE *, tree);
 874 extern void debug_all_mem_sym_stats (void);
 875
 876 /* Call-back function for walk_use_def_chains().  At each reaching
 877    definition, a function with this prototype is called.  */
 878 typedef bool (*walk_use_def_chains_fn) (tree, tree, void *);
 879
 880 /* In tree-ssa-alias-warnings.c  */
 881 extern void strict_aliasing_warning_backend (void);
 882
 883
 884 /* In tree-ssa.c  */
 885
 886 /* Mapping for redirected edges.  */
 887 struct _edge_var_map GTY(())
 888 {
 889   tree result;                  /* PHI result.  */
 890   tree def;                     /* PHI arg definition.  */
 891 };
 892 typedef struct _edge_var_map edge_var_map;
 893
 894 DEF_VEC_O(edge_var_map);
 895 DEF_VEC_ALLOC_O(edge_var_map, heap);
 896
 897 /* A vector of var maps.  */
 898 typedef VEC(edge_var_map, heap) *edge_var_map_vector;
 899
 900 extern void init_tree_ssa (struct function *);
 901 extern void redirect_edge_var_map_add (edge, tree, tree);
 902 extern void redirect_edge_var_map_clear (edge);
 903 extern void redirect_edge_var_map_dup (edge, edge);
 904 extern edge_var_map_vector redirect_edge_var_map_vector (edge);
 905 extern void redirect_edge_var_map_destroy (void);
 906
 907 extern edge ssa_redirect_edge (edge, basic_block);
 908 extern void flush_pending_stmts (edge);
 909 extern bool tree_ssa_useless_type_conversion (tree);
 910 extern bool useless_type_conversion_p (tree, tree);
 911 extern bool types_compatible_p (tree, tree);
 912 extern void verify_ssa (bool);
 913 extern void delete_tree_ssa (void);
 914 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
 915 extern bool stmt_references_memory_p (tree);
 916 extern bool ssa_undefined_value_p (tree);
 917
 918
 919 /* In tree-into-ssa.c  */
 920 void update_ssa (unsigned);
 921 void delete_update_ssa (void);
 922 void register_new_name_mapping (tree, tree);
 923 tree create_new_def_for (tree, tree, def_operand_p);
 924 bool need_ssa_update_p (void);
 925 bool name_mappings_registered_p (void);
 926 bool name_registered_for_update_p (tree);
 927 bitmap ssa_names_to_replace (void);
 928 void release_ssa_name_after_update_ssa (tree);
 929 void compute_global_livein (bitmap, bitmap);
 930 tree duplicate_ssa_name (tree, tree);
 931 void mark_sym_for_renaming (tree);
 932 void mark_set_for_renaming (bitmap);
 933 tree get_current_def (tree);
 934 void set_current_def (tree, tree);
 935
 936 /* In tree-ssanames.c  */
 937 extern void init_ssanames (struct function *, int);
 938 extern void fini_ssanames (void);
 939 extern tree make_ssa_name_fn (struct function *, tree, tree);
 940 extern tree duplicate_ssa_name (tree, tree);
 941 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *);
 942 extern void release_ssa_name (tree);
 943 extern void release_defs (tree);
 944 extern void replace_ssa_name_symbol (tree, tree);
 945
 946 #ifdef GATHER_STATISTICS
 947 extern void ssanames_print_statistics (void);
 948 #endif
 949
 950 /* In tree-ssa-ccp.c  */
 951 bool fold_stmt (tree *);
 952 bool fold_stmt_inplace (tree);
 953 tree get_symbol_constant_value (tree);
 954 tree fold_const_aggregate_ref (tree);
 955
 956 /* In tree-vrp.c  */
 957 tree vrp_evaluate_conditional (enum tree_code, tree, tree, tree);
 958 void simplify_stmt_using_ranges (tree);
 959
 960 /* In tree-ssa-dom.c  */
 961 extern void dump_dominator_optimization_stats (FILE *);
 962 extern void debug_dominator_optimization_stats (void);
 963 int loop_depth_of_name (tree);
 964
 965 /* In tree-ssa-copy.c  */
 966 extern void merge_alias_info (tree, tree);
 967 extern void propagate_value (use_operand_p, tree);
 968 extern void propagate_tree_value (tree *, tree);
 969 extern void replace_exp (use_operand_p, tree);
 970 extern bool may_propagate_copy (tree, tree);
 971 extern bool may_propagate_copy_into_asm (tree);
 972
 973 /* Affine iv.  */
 974
 975 typedef struct
 976 {
 977   /* Iv = BASE + STEP * i.  */
 978   tree base, step;
 979
 980   /* True if this iv does not overflow.  */
 981   bool no_overflow;
 982 } affine_iv;
 983
 984 /* Description of number of iterations of a loop.  All the expressions inside
 985    the structure can be evaluated at the end of the loop's preheader
 986    (and due to ssa form, also anywhere inside the body of the loop).  */
 987
 988 struct tree_niter_desc
 989 {
 990   tree assumptions;     /* The boolean expression.  If this expression evaluates
 991                            to false, then the other fields in this structure
 992                            should not be used; there is no guarantee that they
 993                            will be correct.  */
 994   tree may_be_zero;     /* The boolean expression.  If it evaluates to true,
 995                            the loop will exit in the first iteration (i.e.
 996                            its latch will not be executed), even if the niter
 997                            field says otherwise.  */
 998   tree niter;           /* The expression giving the number of iterations of
 999                            a loop (provided that assumptions == true and
1000                            may_be_zero == false), more precisely the number
1001                            of executions of the latch of the loop.  */
1002   double_int max;       /* The upper bound on the number of iterations of
1003                            the loop.  */
1004
1005   /* The simplified shape of the exit condition.  The loop exits if
1006      CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
1007      LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
1008      LE_EXPR and negative if CMP is GE_EXPR.  This information is used
1009      by loop unrolling.  */
1010   affine_iv control;
1011   tree bound;
1012   enum tree_code cmp;
1013 };
1014
1015 /* In tree-vectorizer.c */
1016 unsigned vectorize_loops (void);
1017 extern bool vect_can_force_dr_alignment_p (const_tree, unsigned int);
1018 extern tree get_vectype_for_scalar_type (tree);
1019
1020 /* In tree-ssa-phiopt.c */
1021 bool empty_block_p (basic_block);
1022 basic_block *blocks_in_phiopt_order (void);
1023
1024 /* In tree-ssa-loop*.c  */
1025
1026 void tree_ssa_lim (void);
1027 unsigned int tree_ssa_unswitch_loops (void);
1028 unsigned int canonicalize_induction_variables (void);
1029 unsigned int tree_unroll_loops_completely (bool, bool);
1030 unsigned int tree_ssa_prefetch_arrays (void);
1031 unsigned int remove_empty_loops (void);
1032 void tree_ssa_iv_optimize (void);
1033 unsigned tree_predictive_commoning (void);
1034 bool parallelize_loops (void);
1035
1036 bool number_of_iterations_exit (struct loop *, edge,
1037                                 struct tree_niter_desc *niter, bool);
1038 tree find_loop_niter (struct loop *, edge *);
1039 tree loop_niter_by_eval (struct loop *, edge);
1040 tree find_loop_niter_by_eval (struct loop *, edge *);
1041 void estimate_numbers_of_iterations (void);
1042 bool scev_probably_wraps_p (tree, tree, tree, struct loop *, bool);
1043 bool convert_affine_scev (struct loop *, tree, tree *, tree *, tree, bool);
1044
1045 bool nowrap_type_p (tree);
1046 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
1047 enum ev_direction scev_direction (const_tree);
1048
1049 void free_numbers_of_iterations_estimates (void);
1050 void free_numbers_of_iterations_estimates_loop (struct loop *);
1051 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
1052 void verify_loop_closed_ssa (void);
1053 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
1054 void create_iv (tree, tree, tree, struct loop *, block_stmt_iterator *, bool,
1055                 tree *, tree *);
1056 basic_block split_loop_exit_edge (edge);
1057 void standard_iv_increment_position (struct loop *, block_stmt_iterator *,
1058                                      bool *);
1059 basic_block ip_end_pos (struct loop *);
1060 basic_block ip_normal_pos (struct loop *);
1061 bool tree_duplicate_loop_to_header_edge (struct loop *, edge,
1062                                          unsigned int, sbitmap,
1063                                          edge, VEC (edge, heap) **,
1064                                          int);
1065 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge);
1066 void rename_variables_in_loop (struct loop *);
1067 struct loop *tree_ssa_loop_version (struct loop *, tree,
1068                                     basic_block *);
1069 tree expand_simple_operations (tree);
1070 void substitute_in_loop_info (struct loop *, tree, tree);
1071 edge single_dom_exit (struct loop *);
1072 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
1073                         struct tree_niter_desc *niter);
1074 void tree_unroll_loop (struct loop *, unsigned,
1075                        edge, struct tree_niter_desc *);
1076 typedef void (*transform_callback)(struct loop *, void *);
1077 void tree_transform_and_unroll_loop (struct loop *, unsigned,
1078                                      edge, struct tree_niter_desc *,
1079                                      transform_callback, void *);
1080 bool contains_abnormal_ssa_name_p (tree);
1081 bool stmt_dominates_stmt_p (tree, tree);
1082 void mark_virtual_ops_for_renaming (tree);
1083
1084 /* In tree-ssa-threadedge.c */
1085 extern bool potentially_threadable_block (basic_block);
1086 extern void thread_across_edge (tree, edge, bool,
1087                                 VEC(tree, heap) **, tree (*) (tree, tree));
1088
1089 /* In tree-ssa-loop-im.c  */
1090 /* The possibilities of statement movement.  */
1091
1092 enum move_pos
1093   {
1094     MOVE_IMPOSSIBLE,            /* No movement -- side effect expression.  */
1095     MOVE_PRESERVE_EXECUTION,    /* Must not cause the non-executed statement
1096                                    become executed -- memory accesses, ... */
1097     MOVE_POSSIBLE               /* Unlimited movement.  */
1098   };
1099 extern enum move_pos movement_possibility (tree);
1100 char *get_lsm_tmp_name (tree, unsigned);
1101
1102 /* In tree-flow-inline.h  */
1103 static inline bool is_call_clobbered (const_tree);
1104 static inline void mark_call_clobbered (tree, unsigned int);
1105 static inline void set_is_used (tree);
1106 static inline bool unmodifiable_var_p (const_tree);
1107
1108 /* In tree-eh.c  */
1109 extern void make_eh_edges (tree);
1110 extern bool tree_could_trap_p (tree);
1111 extern bool tree_could_throw_p (tree);
1112 extern bool tree_can_throw_internal (const_tree);
1113 extern bool tree_can_throw_external (tree);
1114 extern int lookup_stmt_eh_region (const_tree);
1115 extern void add_stmt_to_eh_region (tree, int);
1116 extern bool remove_stmt_from_eh_region (tree);
1117 extern bool maybe_clean_or_replace_eh_stmt (tree, tree);
1118
1119 /* In tree-ssa-pre.c  */
1120 void add_to_value (tree, tree);
1121 void debug_value_expressions (tree);
1122 void print_value_expressions (FILE *, tree);
1123
1124
1125 /* In tree-vn.c  */
1126 tree make_value_handle (tree);
1127 void set_value_handle (tree, tree);
1128 bool expressions_equal_p (tree, tree);
1129 static inline tree get_value_handle (tree);
1130 void sort_vuses (VEC (tree, gc) *);
1131 void sort_vuses_heap (VEC (tree, heap) *);
1132 tree vn_lookup_or_add (tree);
1133 tree vn_lookup_or_add_with_stmt (tree, tree);
1134 tree vn_lookup_or_add_with_vuses (tree, VEC (tree, gc) *);
1135 void vn_add (tree, tree);
1136 void vn_add_with_vuses (tree, tree, VEC (tree, gc) *);
1137 tree vn_lookup_with_stmt (tree, tree);
1138 tree vn_lookup (tree);
1139 tree vn_lookup_with_vuses (tree, VEC (tree, gc) *);
1140
1141 /* In tree-ssa-sink.c  */
1142 bool is_hidden_global_store (tree);
1143
1144 /* In tree-sra.c  */
1145 void insert_edge_copies (tree, basic_block);
1146 void sra_insert_before (block_stmt_iterator *, tree);
1147 void sra_insert_after (block_stmt_iterator *, tree);
1148 void sra_init_cache (void);
1149 bool sra_type_can_be_decomposed_p (tree);
1150
1151 /* In tree-loop-linear.c  */
1152 extern void linear_transform_loops (void);
1153
1154 /* In tree-data-ref.c  */
1155 extern void tree_check_data_deps (void);
1156
1157 /* In tree-ssa-loop-ivopts.c  */
1158 bool expr_invariant_in_loop_p (struct loop *, tree);
1159 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode);
1160 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode);
1161
1162 /* In tree-ssa-threadupdate.c.  */
1163 extern bool thread_through_all_blocks (bool);
1164 extern void register_jump_thread (edge, edge);
1165
1166 /* In gimplify.c  */
1167 tree force_gimple_operand (tree, tree *, bool, tree);
1168 tree force_gimple_operand_bsi (block_stmt_iterator *, tree, bool, tree,
1169                                bool, enum bsi_iterator_update);
1170 tree gimple_fold_indirect_ref (tree);
1171
1172 /* In tree-ssa-structalias.c */
1173 bool find_what_p_points_to (tree);
1174
1175 /* In tree-ssa-live.c */
1176 extern void remove_unused_locals (void);
1177
1178 /* In tree-ssa-address.c  */
1179
1180 /* Description of a memory address.  */
1181
1182 struct mem_address
1183 {
1184   tree symbol, base, index, step, offset;
1185 };
1186
1187 struct affine_tree_combination;
1188 tree create_mem_ref (block_stmt_iterator *, tree,
1189                      struct affine_tree_combination *);
1190 rtx addr_for_mem_ref (struct mem_address *, bool);
1191 void get_address_description (tree, struct mem_address *);
1192 tree maybe_fold_tmr (tree);
1193
1194 void init_alias_heapvars (void);
1195 void delete_alias_heapvars (void);
1196 unsigned int execute_fixup_cfg (void);
1197
1198 #include "tree-flow-inline.h"
1199
1200 void swap_tree_operands (tree, tree *, tree *);
1201
1202 int least_common_multiple (int, int);
1203
1204 #endif /* _TREE_FLOW_H  */