1 /* Data and Control Flow Analysis for Trees. 2 Copyright (C) 2001-2013 Free Software Foundation, Inc. 3 Contributed by Diego Novillo <dnovillo (at) redhat.com> 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3, or (at your option) 10 any later version. 11 12 GCC is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 #ifndef _TREE_FLOW_H 22 #define _TREE_FLOW_H 1 23 24 #include "bitmap.h" 25 #include "sbitmap.h" 26 #include "basic-block.h" 27 #include "hashtab.h" 28 #include "gimple.h" 29 #include "tree-ssa-operands.h" 30 #include "cgraph.h" 31 #include "ipa-reference.h" 32 #include "tree-ssa-alias.h" 33 34 35 /* This structure is used to map a gimple statement to a label, 36 or list of labels to represent transaction restart. */ 37 38 struct GTY(()) tm_restart_node { 39 gimple stmt; 40 tree label_or_list; 41 }; 42 43 /* Gimple dataflow datastructure. All publicly available fields shall have 44 gimple_ accessor defined in tree-flow-inline.h, all publicly modifiable 45 fields should have gimple_set accessor. */ 46 struct GTY(()) gimple_df { 47 /* A vector of all the noreturn calls passed to modify_stmt. 48 cleanup_control_flow uses it to detect cases where a mid-block 49 indirect call has been turned into a noreturn call. When this 50 happens, all the instructions after the call are no longer 51 reachable and must be deleted as dead. */ 52 vec<gimple, va_gc> *modified_noreturn_calls; 53 54 /* Array of all SSA_NAMEs used in the function. */ 55 vec<tree, va_gc> *ssa_names; 56 57 /* Artificial variable used for the virtual operand FUD chain. */ 58 tree vop; 59 60 /* The PTA solution for the ESCAPED artificial variable. */ 61 struct pt_solution escaped; 62 63 /* A map of decls to artificial ssa-names that point to the partition 64 of the decl. */ 65 struct pointer_map_t * GTY((skip(""))) decls_to_pointers; 66 67 /* Free list of SSA_NAMEs. */ 68 vec<tree, va_gc> *free_ssanames; 69 70 /* Hashtable holding definition for symbol. If this field is not NULL, it 71 means that the first reference to this variable in the function is a 72 USE or a VUSE. In those cases, the SSA renamer creates an SSA name 73 for this variable with an empty defining statement. */ 74 htab_t GTY((param_is (union tree_node))) default_defs; 75 76 /* True if there are any symbols that need to be renamed. */ 77 unsigned int ssa_renaming_needed : 1; 78 79 /* True if all virtual operands need to be renamed. */ 80 unsigned int rename_vops : 1; 81 82 /* True if the code is in ssa form. */ 83 unsigned int in_ssa_p : 1; 84 85 /* True if IPA points-to information was computed for this function. */ 86 unsigned int ipa_pta : 1; 87 88 struct ssa_operands ssa_operands; 89 90 /* Map gimple stmt to tree label (or list of labels) for transaction 91 restart and abort. */ 92 htab_t GTY ((param_is (struct tm_restart_node))) tm_restart; 93 }; 94 95 /* Accessors for internal use only. Generic code should use abstraction 96 provided by tree-flow-inline.h or specific modules. */ 97 #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames 98 #define SSANAMES(fun) (fun)->gimple_df->ssa_names 99 #define MODIFIED_NORETURN_CALLS(fun) (fun)->gimple_df->modified_noreturn_calls 100 #define DEFAULT_DEFS(fun) (fun)->gimple_df->default_defs 101 102 typedef struct 103 { 104 htab_t htab; 105 PTR *slot; 106 PTR *limit; 107 } htab_iterator; 108 109 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER, 110 storing each element in RESULT, which is of type TYPE. */ 111 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \ 112 for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \ 113 !end_htab_p (&(ITER)); \ 114 RESULT = (TYPE) next_htab_element (&(ITER))) 115 116 /*--------------------------------------------------------------------------- 117 Attributes for SSA_NAMEs. 118 119 NOTE: These structures are stored in struct tree_ssa_name 120 but are only used by the tree optimizers, so it makes better sense 121 to declare them here to avoid recompiling unrelated files when 122 making changes. 123 ---------------------------------------------------------------------------*/ 124 125 /* Aliasing information for SSA_NAMEs representing pointer variables. */ 126 127 struct GTY(()) ptr_info_def 128 { 129 /* The points-to solution. */ 130 struct pt_solution pt; 131 132 /* Alignment and misalignment of the pointer in bytes. Together 133 align and misalign specify low known bits of the pointer. 134 ptr & (align - 1) == misalign. */ 135 136 /* When known, this is the power-of-two byte alignment of the object this 137 pointer points into. This is usually DECL_ALIGN_UNIT for decls and 138 MALLOC_ABI_ALIGNMENT for allocated storage. When the alignment is not 139 known, it is zero. Do not access directly but use functions 140 get_ptr_info_alignment, set_ptr_info_alignment, 141 mark_ptr_info_alignment_unknown and similar. */ 142 unsigned int align; 143 144 /* When alignment is known, the byte offset this pointer differs from the 145 above alignment. Access only through the same helper functions as align 146 above. */ 147 unsigned int misalign; 148 }; 149 150 151 /* It is advantageous to avoid things like life analysis for variables which 152 do not need PHI nodes. This enum describes whether or not a particular 153 variable may need a PHI node. */ 154 155 enum need_phi_state { 156 /* This is the default. If we are still in this state after finding 157 all the definition and use sites, then we will assume the variable 158 needs PHI nodes. This is probably an overly conservative assumption. */ 159 NEED_PHI_STATE_UNKNOWN, 160 161 /* This state indicates that we have seen one or more sets of the 162 variable in a single basic block and that the sets dominate all 163 uses seen so far. If after finding all definition and use sites 164 we are still in this state, then the variable does not need any 165 PHI nodes. */ 166 NEED_PHI_STATE_NO, 167 168 /* This state indicates that we have either seen multiple definitions of 169 the variable in multiple blocks, or that we encountered a use in a 170 block that was not dominated by the block containing the set(s) of 171 this variable. This variable is assumed to need PHI nodes. */ 172 NEED_PHI_STATE_MAYBE 173 }; 174 175 176 /* Immediate use lists are used to directly access all uses for an SSA 177 name and get pointers to the statement for each use. 178 179 The structure ssa_use_operand_d consists of PREV and NEXT pointers 180 to maintain the list. A USE pointer, which points to address where 181 the use is located and a LOC pointer which can point to the 182 statement where the use is located, or, in the case of the root 183 node, it points to the SSA name itself. 184 185 The list is anchored by an occurrence of ssa_operand_d *in* the 186 ssa_name node itself (named 'imm_uses'). This node is uniquely 187 identified by having a NULL USE pointer. and the LOC pointer 188 pointing back to the ssa_name node itself. This node forms the 189 base for a circular list, and initially this is the only node in 190 the list. 191 192 Fast iteration allows each use to be examined, but does not allow 193 any modifications to the uses or stmts. 194 195 Normal iteration allows insertion, deletion, and modification. the 196 iterator manages this by inserting a marker node into the list 197 immediately before the node currently being examined in the list. 198 this marker node is uniquely identified by having null stmt *and* a 199 null use pointer. 200 201 When iterating to the next use, the iteration routines check to see 202 if the node after the marker has changed. if it has, then the node 203 following the marker is now the next one to be visited. if not, the 204 marker node is moved past that node in the list (visualize it as 205 bumping the marker node through the list). this continues until 206 the marker node is moved to the original anchor position. the 207 marker node is then removed from the list. 208 209 If iteration is halted early, the marker node must be removed from 210 the list before continuing. */ 211 typedef struct immediate_use_iterator_d 212 { 213 /* This is the current use the iterator is processing. */ 214 ssa_use_operand_t *imm_use; 215 /* This marks the last use in the list (use node from SSA_NAME) */ 216 ssa_use_operand_t *end_p; 217 /* This node is inserted and used to mark the end of the uses for a stmt. */ 218 ssa_use_operand_t iter_node; 219 /* This is the next ssa_name to visit. IMM_USE may get removed before 220 the next one is traversed to, so it must be cached early. */ 221 ssa_use_operand_t *next_imm_name; 222 } imm_use_iterator; 223 224 225 /* Use this iterator when simply looking at stmts. Adding, deleting or 226 modifying stmts will cause this iterator to malfunction. */ 227 228 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR) \ 229 for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR)); \ 230 !end_readonly_imm_use_p (&(ITER)); \ 231 (void) ((DEST) = next_readonly_imm_use (&(ITER)))) 232 233 /* Use this iterator to visit each stmt which has a use of SSAVAR. */ 234 235 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR) \ 236 for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR)); \ 237 !end_imm_use_stmt_p (&(ITER)); \ 238 (void) ((STMT) = next_imm_use_stmt (&(ITER)))) 239 240 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early. Failure to 241 do so will result in leaving a iterator marker node in the immediate 242 use list, and nothing good will come from that. */ 243 #define BREAK_FROM_IMM_USE_STMT(ITER) \ 244 { \ 245 end_imm_use_stmt_traverse (&(ITER)); \ 246 break; \ 247 } 248 249 250 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to 251 get access to each occurrence of ssavar on the stmt returned by 252 that iterator.. for instance: 253 254 FOR_EACH_IMM_USE_STMT (stmt, iter, var) 255 { 256 FOR_EACH_IMM_USE_ON_STMT (use_p, iter) 257 { 258 SET_USE (use_p, blah); 259 } 260 update_stmt (stmt); 261 } */ 262 263 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER) \ 264 for ((DEST) = first_imm_use_on_stmt (&(ITER)); \ 265 !end_imm_use_on_stmt_p (&(ITER)); \ 266 (void) ((DEST) = next_imm_use_on_stmt (&(ITER)))) 267 268 269 270 static inline void update_stmt (gimple); 271 static inline int get_lineno (const_gimple); 272 273 /* Accessors for basic block annotations. */ 274 static inline gimple_seq phi_nodes (const_basic_block); 275 static inline void set_phi_nodes (basic_block, gimple_seq); 276 277 /*--------------------------------------------------------------------------- 278 Global declarations 279 ---------------------------------------------------------------------------*/ 280 struct int_tree_map { 281 unsigned int uid; 282 tree to; 283 }; 284 285 extern unsigned int int_tree_map_hash (const void *); 286 extern int int_tree_map_eq (const void *, const void *); 287 288 extern unsigned int uid_decl_map_hash (const void *); 289 extern int uid_decl_map_eq (const void *, const void *); 290 291 #define num_ssa_names (vec_safe_length (cfun->gimple_df->ssa_names)) 292 #define ssa_name(i) ((*cfun->gimple_df->ssa_names)[(i)]) 293 294 /* Macros for showing usage statistics. */ 295 #define SCALE(x) ((unsigned long) ((x) < 1024*10 \ 296 ? (x) \ 297 : ((x) < 1024*1024*10 \ 298 ? (x) / 1024 \ 299 : (x) / (1024*1024)))) 300 301 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M')) 302 303 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y)) 304 305 /*--------------------------------------------------------------------------- 306 OpenMP Region Tree 307 ---------------------------------------------------------------------------*/ 308 309 /* Parallel region information. Every parallel and workshare 310 directive is enclosed between two markers, the OMP_* directive 311 and a corresponding OMP_RETURN statement. */ 312 313 struct omp_region 314 { 315 /* The enclosing region. */ 316 struct omp_region *outer; 317 318 /* First child region. */ 319 struct omp_region *inner; 320 321 /* Next peer region. */ 322 struct omp_region *next; 323 324 /* Block containing the omp directive as its last stmt. */ 325 basic_block entry; 326 327 /* Block containing the OMP_RETURN as its last stmt. */ 328 basic_block exit; 329 330 /* Block containing the OMP_CONTINUE as its last stmt. */ 331 basic_block cont; 332 333 /* If this is a combined parallel+workshare region, this is a list 334 of additional arguments needed by the combined parallel+workshare 335 library call. */ 336 vec<tree, va_gc> *ws_args; 337 338 /* The code for the omp directive of this region. */ 339 enum gimple_code type; 340 341 /* Schedule kind, only used for OMP_FOR type regions. */ 342 enum omp_clause_schedule_kind sched_kind; 343 344 /* True if this is a combined parallel+workshare region. */ 345 bool is_combined_parallel; 346 }; 347 348 extern struct omp_region *root_omp_region; 349 extern struct omp_region *new_omp_region (basic_block, enum gimple_code, 350 struct omp_region *); 351 extern void free_omp_regions (void); 352 void omp_expand_local (basic_block); 353 extern tree find_omp_clause (tree, enum omp_clause_code); 354 tree copy_var_decl (tree, tree, tree); 355 356 /*--------------------------------------------------------------------------- 357 Function prototypes 358 ---------------------------------------------------------------------------*/ 359 /* In tree-cfg.c */ 360 361 /* Location to track pending stmt for edge insertion. */ 362 #define PENDING_STMT(e) ((e)->insns.g) 363 364 extern void delete_tree_cfg_annotations (void); 365 extern bool stmt_ends_bb_p (gimple); 366 extern bool is_ctrl_stmt (gimple); 367 extern bool is_ctrl_altering_stmt (gimple); 368 extern bool simple_goto_p (gimple); 369 extern bool stmt_can_make_abnormal_goto (gimple); 370 extern basic_block single_noncomplex_succ (basic_block bb); 371 extern void gimple_dump_bb (FILE *, basic_block, int, int); 372 extern void gimple_debug_bb (basic_block); 373 extern basic_block gimple_debug_bb_n (int); 374 extern void gimple_dump_cfg (FILE *, int); 375 extern void gimple_debug_cfg (int); 376 extern void dump_cfg_stats (FILE *); 377 extern void dot_cfg (void); 378 extern void debug_cfg_stats (void); 379 extern void debug_loops (int); 380 extern void debug_loop (struct loop *, int); 381 extern void debug_loop_num (unsigned, int); 382 extern void print_loops (FILE *, int); 383 extern void print_loops_bb (FILE *, basic_block, int, int); 384 extern void cleanup_dead_labels (void); 385 extern void group_case_labels_stmt (gimple); 386 extern void group_case_labels (void); 387 extern gimple first_stmt (basic_block); 388 extern gimple last_stmt (basic_block); 389 extern gimple last_and_only_stmt (basic_block); 390 extern edge find_taken_edge (basic_block, tree); 391 extern basic_block label_to_block_fn (struct function *, tree); 392 #define label_to_block(t) (label_to_block_fn (cfun, t)) 393 extern void notice_special_calls (gimple); 394 extern void clear_special_calls (void); 395 extern void verify_gimple_in_seq (gimple_seq); 396 extern void verify_gimple_in_cfg (struct function *); 397 extern tree gimple_block_label (basic_block); 398 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *); 399 extern bool gimple_duplicate_sese_region (edge, edge, basic_block *, unsigned, 400 basic_block *); 401 extern bool gimple_duplicate_sese_tail (edge, edge, basic_block *, unsigned, 402 basic_block *); 403 extern void gather_blocks_in_sese_region (basic_block entry, basic_block exit, 404 vec<basic_block> *bbs_p); 405 extern void add_phi_args_after_copy_bb (basic_block); 406 extern void add_phi_args_after_copy (basic_block *, unsigned, edge); 407 extern bool gimple_purge_dead_eh_edges (basic_block); 408 extern bool gimple_purge_all_dead_eh_edges (const_bitmap); 409 extern bool gimple_purge_dead_abnormal_call_edges (basic_block); 410 extern bool gimple_purge_all_dead_abnormal_call_edges (const_bitmap); 411 extern tree gimplify_build1 (gimple_stmt_iterator *, enum tree_code, 412 tree, tree); 413 extern tree gimplify_build2 (gimple_stmt_iterator *, enum tree_code, 414 tree, tree, tree); 415 extern tree gimplify_build3 (gimple_stmt_iterator *, enum tree_code, 416 tree, tree, tree, tree); 417 extern void init_empty_tree_cfg (void); 418 extern void init_empty_tree_cfg_for_function (struct function *); 419 extern void fold_cond_expr_cond (void); 420 extern void make_abnormal_goto_edges (basic_block, bool); 421 extern void replace_uses_by (tree, tree); 422 extern void start_recording_case_labels (void); 423 extern void end_recording_case_labels (void); 424 extern basic_block move_sese_region_to_fn (struct function *, basic_block, 425 basic_block, tree); 426 void remove_edge_and_dominated_blocks (edge); 427 bool tree_node_can_be_shared (tree); 428 extern unsigned int split_critical_edges (void); 429 430 /* In tree-cfgcleanup.c */ 431 extern bitmap cfgcleanup_altered_bbs; 432 extern bool cleanup_tree_cfg (void); 433 434 /* In tree-pretty-print.c. */ 435 extern void dump_generic_bb (FILE *, basic_block, int, int); 436 extern int op_code_prio (enum tree_code); 437 extern int op_prio (const_tree); 438 extern const char *op_symbol_code (enum tree_code); 439 440 /* In tree-dfa.c */ 441 extern void renumber_gimple_stmt_uids (void); 442 extern void renumber_gimple_stmt_uids_in_blocks (basic_block *, int); 443 extern void dump_dfa_stats (FILE *); 444 extern void debug_dfa_stats (void); 445 extern void dump_variable (FILE *, tree); 446 extern void debug_variable (tree); 447 extern void set_ssa_default_def (struct function *, tree, tree); 448 extern tree ssa_default_def (struct function *, tree); 449 extern tree get_or_create_ssa_default_def (struct function *, tree); 450 extern bool stmt_references_abnormal_ssa_name (gimple); 451 extern tree get_addr_base_and_unit_offset (tree, HOST_WIDE_INT *); 452 extern void dump_enumerated_decls (FILE *, int); 453 454 /* In tree-phinodes.c */ 455 extern void reserve_phi_args_for_new_edge (basic_block); 456 extern void add_phi_node_to_bb (gimple phi, basic_block bb); 457 extern gimple create_phi_node (tree, basic_block); 458 extern void add_phi_arg (gimple, tree, edge, source_location); 459 extern void remove_phi_args (edge); 460 extern void remove_phi_node (gimple_stmt_iterator *, bool); 461 extern void remove_phi_nodes (basic_block); 462 extern void release_phi_node (gimple); 463 extern void phinodes_print_statistics (void); 464 465 /* In gimple-low.c */ 466 extern void record_vars_into (tree, tree); 467 extern void record_vars (tree); 468 extern bool gimple_seq_may_fallthru (gimple_seq); 469 extern bool gimple_stmt_may_fallthru (gimple); 470 extern bool gimple_check_call_matching_types (gimple, tree); 471 472 473 /* In tree-ssa.c */ 474 475 /* Mapping for redirected edges. */ 476 struct _edge_var_map { 477 tree result; /* PHI result. */ 478 tree def; /* PHI arg definition. */ 479 source_location locus; /* PHI arg location. */ 480 }; 481 typedef struct _edge_var_map edge_var_map; 482 483 484 /* A vector of var maps. */ 485 typedef vec<edge_var_map, va_heap, vl_embed> edge_var_map_vector; 486 487 extern void init_tree_ssa (struct function *); 488 extern void redirect_edge_var_map_add (edge, tree, tree, source_location); 489 extern void redirect_edge_var_map_clear (edge); 490 extern void redirect_edge_var_map_dup (edge, edge); 491 extern edge_var_map_vector *redirect_edge_var_map_vector (edge); 492 extern void redirect_edge_var_map_destroy (void); 493 494 extern edge ssa_redirect_edge (edge, basic_block); 495 extern void flush_pending_stmts (edge); 496 extern void verify_ssa (bool); 497 extern void delete_tree_ssa (void); 498 extern bool ssa_undefined_value_p (tree); 499 extern void warn_uninit (enum opt_code, tree, tree, tree, const char *, void *); 500 extern unsigned int warn_uninitialized_vars (bool); 501 extern void execute_update_addresses_taken (void); 502 503 /* Call-back function for walk_use_def_chains(). At each reaching 504 definition, a function with this prototype is called. */ 505 typedef bool (*walk_use_def_chains_fn) (tree, gimple, void *); 506 507 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool); 508 509 void insert_debug_temps_for_defs (gimple_stmt_iterator *); 510 void insert_debug_temp_for_var_def (gimple_stmt_iterator *, tree); 511 void reset_debug_uses (gimple); 512 void release_defs_bitset (bitmap toremove); 513 514 /* In tree-into-ssa.c */ 515 void update_ssa (unsigned); 516 void delete_update_ssa (void); 517 tree create_new_def_for (tree, gimple, def_operand_p); 518 bool need_ssa_update_p (struct function *); 519 bool name_registered_for_update_p (tree); 520 void release_ssa_name_after_update_ssa (tree); 521 void mark_virtual_operands_for_renaming (struct function *); 522 tree get_current_def (tree); 523 void set_current_def (tree, tree); 524 525 /* In tree-ssanames.c */ 526 extern void init_ssanames (struct function *, int); 527 extern void fini_ssanames (void); 528 extern tree make_ssa_name_fn (struct function *, tree, gimple); 529 extern tree copy_ssa_name_fn (struct function *, tree, gimple); 530 extern tree duplicate_ssa_name_fn (struct function *, tree, gimple); 531 extern void duplicate_ssa_name_ptr_info (tree, struct ptr_info_def *); 532 extern void release_ssa_name (tree); 533 extern void release_defs (gimple); 534 extern void replace_ssa_name_symbol (tree, tree); 535 extern bool get_ptr_info_alignment (struct ptr_info_def *, unsigned int *, 536 unsigned int *); 537 extern void mark_ptr_info_alignment_unknown (struct ptr_info_def *); 538 extern void set_ptr_info_alignment (struct ptr_info_def *, unsigned int, 539 unsigned int); 540 extern void adjust_ptr_info_misalignment (struct ptr_info_def *, 541 unsigned int); 542 543 extern void ssanames_print_statistics (void); 544 545 /* In tree-ssa-ccp.c */ 546 tree fold_const_aggregate_ref (tree); 547 tree gimple_fold_stmt_to_constant (gimple, tree (*)(tree)); 548 549 /* In tree-ssa-dom.c */ 550 extern void dump_dominator_optimization_stats (FILE *); 551 extern void debug_dominator_optimization_stats (void); 552 int loop_depth_of_name (tree); 553 tree degenerate_phi_result (gimple); 554 bool simple_iv_increment_p (gimple); 555 556 /* In tree-ssa-copy.c */ 557 extern void propagate_value (use_operand_p, tree); 558 extern void propagate_tree_value (tree *, tree); 559 extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree); 560 extern void replace_exp (use_operand_p, tree); 561 extern bool may_propagate_copy (tree, tree); 562 extern bool may_propagate_copy_into_stmt (gimple, tree); 563 extern bool may_propagate_copy_into_asm (tree); 564 565 /* In tree-ssa-loop-ch.c */ 566 bool do_while_loop_p (struct loop *); 567 568 /* Affine iv. */ 569 570 typedef struct 571 { 572 /* Iv = BASE + STEP * i. */ 573 tree base, step; 574 575 /* True if this iv does not overflow. */ 576 bool no_overflow; 577 } affine_iv; 578 579 /* Description of number of iterations of a loop. All the expressions inside 580 the structure can be evaluated at the end of the loop's preheader 581 (and due to ssa form, also anywhere inside the body of the loop). */ 582 583 struct tree_niter_desc 584 { 585 tree assumptions; /* The boolean expression. If this expression evaluates 586 to false, then the other fields in this structure 587 should not be used; there is no guarantee that they 588 will be correct. */ 589 tree may_be_zero; /* The boolean expression. If it evaluates to true, 590 the loop will exit in the first iteration (i.e. 591 its latch will not be executed), even if the niter 592 field says otherwise. */ 593 tree niter; /* The expression giving the number of iterations of 594 a loop (provided that assumptions == true and 595 may_be_zero == false), more precisely the number 596 of executions of the latch of the loop. */ 597 double_int max; /* The upper bound on the number of iterations of 598 the loop. */ 599 600 /* The simplified shape of the exit condition. The loop exits if 601 CONTROL CMP BOUND is false, where CMP is one of NE_EXPR, 602 LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is 603 LE_EXPR and negative if CMP is GE_EXPR. This information is used 604 by loop unrolling. */ 605 affine_iv control; 606 tree bound; 607 enum tree_code cmp; 608 }; 609 610 /* In tree-ssa-phiopt.c */ 611 bool empty_block_p (basic_block); 612 basic_block *blocks_in_phiopt_order (void); 613 bool nonfreeing_call_p (gimple); 614 615 /* In tree-ssa-loop*.c */ 616 617 unsigned int tree_ssa_lim (void); 618 unsigned int tree_ssa_unswitch_loops (void); 619 unsigned int canonicalize_induction_variables (void); 620 unsigned int tree_unroll_loops_completely (bool, bool); 621 unsigned int tree_ssa_prefetch_arrays (void); 622 void tree_ssa_iv_optimize (void); 623 unsigned tree_predictive_commoning (void); 624 tree canonicalize_loop_ivs (struct loop *, tree *, bool); 625 bool parallelize_loops (void); 626 627 bool loop_only_exit_p (const struct loop *, const_edge); 628 bool number_of_iterations_exit (struct loop *, edge, 629 struct tree_niter_desc *niter, bool, 630 bool every_iteration = true); 631 tree find_loop_niter (struct loop *, edge *); 632 tree loop_niter_by_eval (struct loop *, edge); 633 tree find_loop_niter_by_eval (struct loop *, edge *); 634 void estimate_numbers_of_iterations (void); 635 bool scev_probably_wraps_p (tree, tree, gimple, struct loop *, bool); 636 bool convert_affine_scev (struct loop *, tree, tree *, tree *, gimple, bool); 637 638 bool nowrap_type_p (tree); 639 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN}; 640 enum ev_direction scev_direction (const_tree); 641 642 void free_numbers_of_iterations_estimates (void); 643 void free_numbers_of_iterations_estimates_loop (struct loop *); 644 void rewrite_into_loop_closed_ssa (bitmap, unsigned); 645 void verify_loop_closed_ssa (bool); 646 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *); 647 void create_iv (tree, tree, tree, struct loop *, gimple_stmt_iterator *, bool, 648 tree *, tree *); 649 basic_block split_loop_exit_edge (edge); 650 void standard_iv_increment_position (struct loop *, gimple_stmt_iterator *, 651 bool *); 652 basic_block ip_end_pos (struct loop *); 653 basic_block ip_normal_pos (struct loop *); 654 bool gimple_duplicate_loop_to_header_edge (struct loop *, edge, 655 unsigned int, sbitmap, 656 edge, vec<edge> *, 657 int); 658 struct loop *slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *, edge); 659 tree expand_simple_operations (tree); 660 void substitute_in_loop_info (struct loop *, tree, tree); 661 edge single_dom_exit (struct loop *); 662 bool can_unroll_loop_p (struct loop *loop, unsigned factor, 663 struct tree_niter_desc *niter); 664 void tree_unroll_loop (struct loop *, unsigned, 665 edge, struct tree_niter_desc *); 666 typedef void (*transform_callback)(struct loop *, void *); 667 void tree_transform_and_unroll_loop (struct loop *, unsigned, 668 edge, struct tree_niter_desc *, 669 transform_callback, void *); 670 bool contains_abnormal_ssa_name_p (tree); 671 bool stmt_dominates_stmt_p (gimple, gimple); 672 673 /* In tree-ssa-dce.c */ 674 void mark_virtual_operand_for_renaming (tree); 675 void mark_virtual_phi_result_for_renaming (gimple); 676 677 /* In tree-ssa-threadedge.c */ 678 extern void threadedge_initialize_values (void); 679 extern void threadedge_finalize_values (void); 680 extern vec<tree> ssa_name_values; 681 #define SSA_NAME_VALUE(x) \ 682 (SSA_NAME_VERSION(x) < ssa_name_values.length () \ 683 ? ssa_name_values[SSA_NAME_VERSION(x)] \ 684 : NULL_TREE) 685 extern void set_ssa_name_value (tree, tree); 686 extern bool potentially_threadable_block (basic_block); 687 extern void thread_across_edge (gimple, edge, bool, 688 vec<tree> *, tree (*) (gimple, gimple)); 689 extern void propagate_threaded_block_debug_into (basic_block, basic_block); 690 691 /* In tree-ssa-loop-im.c */ 692 /* The possibilities of statement movement. */ 693 694 enum move_pos 695 { 696 MOVE_IMPOSSIBLE, /* No movement -- side effect expression. */ 697 MOVE_PRESERVE_EXECUTION, /* Must not cause the non-executed statement 698 become executed -- memory accesses, ... */ 699 MOVE_POSSIBLE /* Unlimited movement. */ 700 }; 701 extern enum move_pos movement_possibility (gimple); 702 char *get_lsm_tmp_name (tree, unsigned); 703 704 /* In tree-flow-inline.h */ 705 static inline bool unmodifiable_var_p (const_tree); 706 static inline bool ref_contains_array_ref (const_tree); 707 708 /* In tree-eh.c */ 709 extern void make_eh_edges (gimple); 710 extern bool make_eh_dispatch_edges (gimple); 711 extern edge redirect_eh_edge (edge, basic_block); 712 extern void redirect_eh_dispatch_edge (gimple, edge, basic_block); 713 extern bool stmt_could_throw_p (gimple); 714 extern bool stmt_can_throw_internal (gimple); 715 extern bool stmt_can_throw_external (gimple); 716 extern void add_stmt_to_eh_lp_fn (struct function *, gimple, int); 717 extern void add_stmt_to_eh_lp (gimple, int); 718 extern bool remove_stmt_from_eh_lp (gimple); 719 extern bool remove_stmt_from_eh_lp_fn (struct function *, gimple); 720 extern int lookup_stmt_eh_lp_fn (struct function *, gimple); 721 extern int lookup_stmt_eh_lp (gimple); 722 extern bool maybe_clean_eh_stmt_fn (struct function *, gimple); 723 extern bool maybe_clean_eh_stmt (gimple); 724 extern bool maybe_clean_or_replace_eh_stmt (gimple, gimple); 725 extern bool maybe_duplicate_eh_stmt_fn (struct function *, gimple, 726 struct function *, gimple, 727 struct pointer_map_t *, int); 728 extern bool maybe_duplicate_eh_stmt (gimple, gimple); 729 extern bool verify_eh_edges (gimple); 730 extern bool verify_eh_dispatch_edge (gimple); 731 extern void maybe_remove_unreachable_handlers (void); 732 733 /* In tree-ssa-pre.c */ 734 void debug_value_expressions (unsigned int); 735 736 /* In tree-loop-linear.c */ 737 extern void linear_transform_loops (void); 738 extern unsigned perfect_loop_nest_depth (struct loop *); 739 740 /* In graphite.c */ 741 extern void graphite_transform_loops (void); 742 743 /* In tree-data-ref.c */ 744 extern void tree_check_data_deps (void); 745 746 /* In tree-ssa-loop-ivopts.c */ 747 bool expr_invariant_in_loop_p (struct loop *, tree); 748 bool stmt_invariant_in_loop_p (struct loop *, gimple); 749 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode, 750 addr_space_t); 751 bool may_be_nonaddressable_p (tree expr); 752 753 /* In tree-ssa-threadupdate.c. */ 754 extern bool thread_through_all_blocks (bool); 755 extern void register_jump_thread (edge, edge, edge); 756 757 /* In gimplify.c */ 758 tree force_gimple_operand_1 (tree, gimple_seq *, gimple_predicate, tree); 759 tree force_gimple_operand (tree, gimple_seq *, bool, tree); 760 tree force_gimple_operand_gsi_1 (gimple_stmt_iterator *, tree, 761 gimple_predicate, tree, 762 bool, enum gsi_iterator_update); 763 tree force_gimple_operand_gsi (gimple_stmt_iterator *, tree, bool, tree, 764 bool, enum gsi_iterator_update); 765 tree gimple_fold_indirect_ref (tree); 766 767 /* In tree-ssa-live.c */ 768 extern void remove_unused_locals (void); 769 extern void dump_scope_blocks (FILE *, int); 770 extern void debug_scope_blocks (int); 771 extern void debug_scope_block (tree, int); 772 773 /* In tree-ssa-address.c */ 774 775 /* Description of a memory address. */ 776 777 struct mem_address 778 { 779 tree symbol, base, index, step, offset; 780 }; 781 782 struct affine_tree_combination; 783 tree create_mem_ref (gimple_stmt_iterator *, tree, 784 struct affine_tree_combination *, tree, tree, tree, bool); 785 rtx addr_for_mem_ref (struct mem_address *, addr_space_t, bool); 786 void get_address_description (tree, struct mem_address *); 787 tree maybe_fold_tmr (tree); 788 789 unsigned int execute_fixup_cfg (void); 790 bool fixup_noreturn_call (gimple stmt); 791 792 /* In ipa-pure-const.c */ 793 void warn_function_noreturn (tree); 794 795 /* In tree-ssa-ter.c */ 796 bool stmt_is_replaceable_p (gimple); 797 798 /* In tree-parloops.c */ 799 bool parallelized_function_p (tree); 800 801 #include "tree-flow-inline.h" 802 803 void swap_tree_operands (gimple, tree *, tree *); 804 805 #endif /* _TREE_FLOW_H */ 806
