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>
6 This file is part of GCC.
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 2, or (at your option)
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.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to
20 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
24 #define _TREE_FLOW_H 1
27 #include "hard-reg-set.h"
28 #include "basic-block.h"
30 #include "tree-gimple.h"
31 #include "tree-ssa-operands.h"
33 #include "ipa-reference.h"
35 /* Forward declare structures for the garbage collector GTY markers. */
36 #ifndef GCC_BASIC_BLOCK_H
38 typedef struct edge_def *edge;
39 struct basic_block_def;
40 typedef struct basic_block_def *basic_block;
42 struct static_var_ann_d;
44 /* Memory reference statistics for individual memory symbols,
45 collected during alias analysis. */
46 struct mem_sym_stats_d GTY(())
51 /* Nonzero if this entry has been assigned a partition. */
52 unsigned int partitioned_p : 1;
54 /* Nonzero if VAR is a memory partition tag that already contains
55 call-clobbered variables in its partition set. */
56 unsigned int has_call_clobbered_vars : 1;
58 /* Number of direct reference sites. A direct reference to VAR is any
59 reference of the form 'VAR = ' or ' = VAR'. For GIMPLE reg
60 pointers, this is the number of sites where the pointer is
62 long num_direct_writes;
63 long num_direct_reads;
65 /* Number of indirect reference sites. An indirect reference to VAR
66 is any reference via a pointer that contains VAR in its points-to
67 set or, in the case of call-clobbered symbols, a function call. */
68 long num_indirect_writes;
69 long num_indirect_reads;
71 /* Execution frequency. This is the sum of the execution
72 frequencies of all the statements that reference this object
73 weighted by the number of references in each statement. This is
74 the main key used to sort the list of symbols to partition.
75 Symbols with high execution frequencies are put at the bottom of
76 the work list (ie, they are partitioned last).
77 Execution frequencies are taken directly from each basic block,
78 so compiling with PGO enabled will increase the precision of this
81 long frequency_writes;
83 /* Set of memory tags that contain VAR in their alias set. */
87 typedef struct mem_sym_stats_d *mem_sym_stats_t;
88 DEF_VEC_P(mem_sym_stats_t);
89 DEF_VEC_ALLOC_P(mem_sym_stats_t, heap);
91 /* Memory reference statistics collected during alias analysis. */
92 struct mem_ref_stats_d GTY(())
94 /* Number of statements that make memory references. */
97 /* Number of statements that make function calls. */
100 /* Number of statements that make calls to pure/const functions. */
101 long num_pure_const_call_sites;
103 /* Number of ASM statements. */
106 /* Estimated number of virtual operands needed as computed by
107 compute_memory_partitions. */
111 /* This maps every symbol used to make "memory" references
112 (pointers, arrays, structures, etc) to an instance of struct
113 mem_sym_stats_d describing reference statistics for the symbol. */
114 struct pointer_map_t * GTY((skip)) mem_sym_stats;
118 /* Gimple dataflow datastructure. All publicly available fields shall have
119 gimple_ accessor defined in tree-flow-inline.h, all publicly modifiable
120 fields should have gimple_set accessor. */
121 struct gimple_df GTY(())
123 /* Array of all variables referenced in the function. */
124 htab_t GTY((param_is (struct int_tree_map))) referenced_vars;
126 /* A list of all the noreturn calls passed to modify_stmt.
127 cleanup_control_flow uses it to detect cases where a mid-block
128 indirect call has been turned into a noreturn call. When this
129 happens, all the instructions after the call are no longer
130 reachable and must be deleted as dead. */
131 VEC(tree,gc) *modified_noreturn_calls;
133 /* Array of all SSA_NAMEs used in the function. */
134 VEC(tree,gc) *ssa_names;
136 /* Artificial variable used to model the effects of function calls. */
139 /* Artificial variable used to model the effects of nonlocal
143 /* Call clobbered variables in the function. If bit I is set, then
144 REFERENCED_VARS (I) is call-clobbered. */
145 bitmap call_clobbered_vars;
147 /* Addressable variables in the function. If bit I is set, then
148 REFERENCED_VARS (I) has had its address taken. Note that
149 CALL_CLOBBERED_VARS and ADDRESSABLE_VARS are not related. An
150 addressable variable is not necessarily call-clobbered (e.g., a
151 local addressable whose address does not escape) and not all
152 call-clobbered variables are addressable (e.g., a local static
154 bitmap addressable_vars;
156 /* Free list of SSA_NAMEs. */
159 /* Hashtable holding definition for symbol. If this field is not NULL, it
160 means that the first reference to this variable in the function is a
161 USE or a VUSE. In those cases, the SSA renamer creates an SSA name
162 for this variable with an empty defining statement. */
163 htab_t GTY((param_is (struct int_tree_map))) default_defs;
165 /* 'true' after aliases have been computed (see compute_may_aliases). */
166 unsigned int aliases_computed_p : 1;
168 /* True if the code is in ssa form. */
169 unsigned int in_ssa_p : 1;
171 struct ssa_operands ssa_operands;
173 /* Hashtable of variables annotations. Used for static variables only;
174 local variables have direct pointer in the tree node. */
175 htab_t GTY((param_is (struct static_var_ann_d))) var_anns;
177 /* Memory reference statistics collected during alias analysis.
178 This information is used to drive the memory partitioning
179 heuristics in compute_memory_partitions. */
180 struct mem_ref_stats_d mem_ref_stats;
183 /* Accessors for internal use only. Generic code should use abstraction
184 provided by tree-flow-inline.h or specific modules. */
185 #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames
186 #define SSANAMES(fun) (fun)->gimple_df->ssa_names
187 #define MODIFIED_NORETURN_CALLS(fun) (fun)->gimple_df->modified_noreturn_calls
188 #define DEFAULT_DEFS(fun) (fun)->gimple_df->default_defs
197 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
198 storing each element in RESULT, which is of type TYPE. */
199 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
200 for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
201 !end_htab_p (&(ITER)); \
202 RESULT = (TYPE) next_htab_element (&(ITER)))
204 /*---------------------------------------------------------------------------
205 Attributes for SSA_NAMEs.
207 NOTE: These structures are stored in struct tree_ssa_name
208 but are only used by the tree optimizers, so it makes better sense
209 to declare them here to avoid recompiling unrelated files when
211 ---------------------------------------------------------------------------*/
213 /* Aliasing information for SSA_NAMEs representing pointer variables. */
214 struct ptr_info_def GTY(())
216 /* Nonzero if points-to analysis couldn't determine where this pointer
218 unsigned int pt_anything : 1;
220 /* Nonzero if the value of this pointer escapes the current function. */
221 unsigned int value_escapes_p : 1;
223 /* Nonzero if this pointer is dereferenced. */
224 unsigned int is_dereferenced : 1;
226 /* Nonzero if this pointer points to a global variable. */
227 unsigned int pt_global_mem : 1;
229 /* Nonzero if this pointer points to NULL. */
230 unsigned int pt_null : 1;
232 /* Set of variables that this pointer may point to. */
235 /* If this pointer has been dereferenced, and points-to information is
236 more precise than type-based aliasing, indirect references to this
237 pointer will be represented by this memory tag, instead of the type
238 tag computed by TBAA. */
241 /* Mask of reasons this pointer's value escapes the function */
242 unsigned int escape_mask;
246 /*---------------------------------------------------------------------------
247 Tree annotations stored in tree_base.ann
248 ---------------------------------------------------------------------------*/
249 enum tree_ann_type { TREE_ANN_COMMON, VAR_ANN, FUNCTION_ANN, STMT_ANN };
251 struct tree_ann_common_d GTY(())
253 /* Annotation type. */
254 enum tree_ann_type type;
256 /* Auxiliary info specific to a pass. At all times, this
257 should either point to valid data or be NULL. */
258 PTR GTY ((skip (""))) aux;
260 /* The value handle for this expression. Used by GVN-PRE. */
261 tree GTY((skip)) value_handle;
264 /* It is advantageous to avoid things like life analysis for variables which
265 do not need PHI nodes. This enum describes whether or not a particular
266 variable may need a PHI node. */
268 enum need_phi_state {
269 /* This is the default. If we are still in this state after finding
270 all the definition and use sites, then we will assume the variable
271 needs PHI nodes. This is probably an overly conservative assumption. */
272 NEED_PHI_STATE_UNKNOWN,
274 /* This state indicates that we have seen one or more sets of the
275 variable in a single basic block and that the sets dominate all
276 uses seen so far. If after finding all definition and use sites
277 we are still in this state, then the variable does not need any
281 /* This state indicates that we have either seen multiple definitions of
282 the variable in multiple blocks, or that we encountered a use in a
283 block that was not dominated by the block containing the set(s) of
284 this variable. This variable is assumed to need PHI nodes. */
289 /* The "no alias" attribute allows alias analysis to make more
290 aggressive assumptions when assigning alias sets, computing
291 points-to information and memory partitions. These attributes
292 are the result of user annotations or flags (e.g.,
293 -fargument-noalias). */
295 /* Default state. No special assumptions can be made about this
299 /* The symbol does not alias with other symbols that have a
300 NO_ALIAS* attribute. */
303 /* The symbol does not alias with other symbols that have a
304 NO_ALIAS*, and it may not alias with global symbols. */
307 /* The symbol does not alias with any other symbols. */
313 typedef struct subvar *subvar_t;
315 /* This structure represents a fake sub-variable for a structure field. */
316 struct subvar GTY(())
321 /* Next subvar for this structure. */
325 struct var_ann_d GTY(())
327 struct tree_ann_common_d common;
329 /* Used by the out of SSA pass to determine whether this variable has
330 been seen yet or not. */
331 unsigned out_of_ssa_tag : 1;
333 /* Used when building base variable structures in a var_map. */
334 unsigned base_var_processed : 1;
336 /* Nonzero if this variable was used after SSA optimizations were
337 applied. We set this when translating out of SSA form. */
340 /* This field indicates whether or not the variable may need PHI nodes.
341 See the enum's definition for more detailed information about the
343 ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
345 /* Used during operand processing to determine if this variable is already
347 unsigned in_vuse_list : 1;
349 /* Used during operand processing to determine if this variable is already
351 unsigned in_vdef_list : 1;
353 /* True for HEAP artificial variables. These variables represent
354 the memory area allocated by a call to malloc. */
355 unsigned is_heapvar : 1;
357 /* True if the variable is call clobbered. */
358 unsigned int call_clobbered : 1;
360 /* This field describes several "no alias" attributes that some
361 symbols are known to have. See the enum's definition for more
362 information on each attribute. */
363 ENUM_BITFIELD (noalias_state) noalias_state : 2;
365 /* Memory partition tag assigned to this symbol. */
368 /* If this variable is a pointer P that has been dereferenced, this
369 field is an artificial variable that represents the memory
370 location *P. Every other pointer Q that is type-compatible with
371 P will also have the same memory tag. If the variable is not a
372 pointer or if it is never dereferenced, this must be NULL.
373 FIXME, do we really need this here? How much slower would it be
374 to convert to hash table? */
377 /* Used when going out of SSA form to indicate which partition this
378 variable represents storage for. */
381 /* Used by var_map for the base index of ssa base variables. */
384 /* During into-ssa and the dominator optimizer, this field holds the
385 current version of this variable (an SSA_NAME). */
388 /* If this variable is a structure, this fields holds a list of
389 symbols representing each of the fields of the structure. */
392 /* Mask of values saying the reasons why this variable has escaped
394 unsigned int escape_mask;
397 /* Container for variable annotation used by hashtable for annotations for
399 struct static_var_ann_d GTY(())
401 struct var_ann_d ann;
405 struct function_ann_d GTY(())
407 struct tree_ann_common_d common;
409 /* Pointer to the structure that contains the sets of global
410 variables modified by function calls. This field is only used
411 for FUNCTION_DECLs. */
412 ipa_reference_vars_info_t GTY ((skip)) reference_vars_info;
415 typedef struct immediate_use_iterator_d
417 /* This is the current use the iterator is processing. */
418 ssa_use_operand_t *imm_use;
419 /* This marks the last use in the list (use node from SSA_NAME) */
420 ssa_use_operand_t *end_p;
421 /* This node is inserted and used to mark the end of the uses for a stmt. */
422 ssa_use_operand_t iter_node;
423 /* This is the next ssa_name to visit. IMM_USE may get removed before
424 the next one is traversed to, so it must be cached early. */
425 ssa_use_operand_t *next_imm_name;
429 /* Use this iterator when simply looking at stmts. Adding, deleting or
430 modifying stmts will cause this iterator to malfunction. */
432 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR) \
433 for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR)); \
434 !end_readonly_imm_use_p (&(ITER)); \
435 (DEST) = next_readonly_imm_use (&(ITER)))
437 /* Use this iterator to visit each stmt which has a use of SSAVAR. */
439 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR) \
440 for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR)); \
441 !end_imm_use_stmt_p (&(ITER)); \
442 (STMT) = next_imm_use_stmt (&(ITER)))
444 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early. Failure to
445 do so will result in leaving a iterator marker node in the immediate
446 use list, and nothing good will come from that. */
447 #define BREAK_FROM_IMM_USE_STMT(ITER) \
449 end_imm_use_stmt_traverse (&(ITER)); \
454 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
455 get access to each occurrence of ssavar on the stmt returned by
456 that iterator.. for instance:
458 FOR_EACH_IMM_USE_STMT (stmt, iter, var)
460 FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
462 SET_USE (use_p) = blah;
467 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER) \
468 for ((DEST) = first_imm_use_on_stmt (&(ITER)); \
469 !end_imm_use_on_stmt_p (&(ITER)); \
470 (DEST) = next_imm_use_on_stmt (&(ITER)))
474 struct stmt_ann_d GTY(())
476 struct tree_ann_common_d common;
478 /* Basic block that contains this statement. */
481 /* Operand cache for stmt. */
482 struct stmt_operands_d GTY ((skip (""))) operands;
484 /* Set of variables that have had their address taken in the statement. */
485 bitmap addresses_taken;
487 /* Unique identifier for this statement. These ID's are to be created
488 by each pass on an as-needed basis in any order convenient for the
489 pass which needs statement UIDs. */
492 /* Nonzero if the statement references memory (at least one of its
493 expressions contains a non-register operand). */
494 unsigned references_memory : 1;
496 /* Nonzero if the statement has been modified (meaning that the operands
497 need to be scanned again). */
498 unsigned modified : 1;
500 /* Nonzero if the statement makes references to volatile storage. */
501 unsigned has_volatile_ops : 1;
503 /* Nonzero if the statement makes a function call that may clobber global
504 and local addressable variables. */
505 unsigned makes_clobbering_call : 1;
508 union tree_ann_d GTY((desc ("ann_type ((tree_ann_t)&%h)")))
510 struct tree_ann_common_d GTY((tag ("TREE_ANN_COMMON"))) common;
511 struct var_ann_d GTY((tag ("VAR_ANN"))) vdecl;
512 struct function_ann_d GTY((tag ("FUNCTION_ANN"))) fdecl;
513 struct stmt_ann_d GTY((tag ("STMT_ANN"))) stmt;
516 typedef union tree_ann_d *tree_ann_t;
517 typedef struct var_ann_d *var_ann_t;
518 typedef struct function_ann_d *function_ann_t;
519 typedef struct stmt_ann_d *stmt_ann_t;
520 typedef struct tree_ann_common_d *tree_ann_common_t;
522 static inline tree_ann_common_t tree_common_ann (tree);
523 static inline tree_ann_common_t get_tree_common_ann (tree);
524 static inline var_ann_t var_ann (tree);
525 static inline var_ann_t get_var_ann (tree);
526 static inline function_ann_t function_ann (tree);
527 static inline function_ann_t get_function_ann (tree);
528 static inline stmt_ann_t stmt_ann (tree);
529 static inline bool has_stmt_ann (tree);
530 static inline stmt_ann_t get_stmt_ann (tree);
531 static inline enum tree_ann_type ann_type (tree_ann_t);
532 static inline basic_block bb_for_stmt (tree);
533 extern void set_bb_for_stmt (tree, basic_block);
534 static inline bool noreturn_call_p (tree);
535 static inline void update_stmt (tree);
536 static inline bool stmt_modified_p (tree);
537 static inline bitmap may_aliases (tree);
538 static inline int get_lineno (tree);
539 static inline const char *get_filename (tree);
540 static inline bool is_exec_stmt (tree);
541 static inline bool is_label_stmt (tree);
542 static inline bitmap addresses_taken (tree);
544 /*---------------------------------------------------------------------------
545 Structure representing predictions in tree level.
546 ---------------------------------------------------------------------------*/
547 struct edge_prediction GTY((chain_next ("%h.ep_next")))
549 struct edge_prediction *ep_next;
551 enum br_predictor ep_predictor;
555 /* Accessors for basic block annotations. */
556 static inline tree phi_nodes (basic_block);
557 static inline void set_phi_nodes (basic_block, tree);
559 /*---------------------------------------------------------------------------
561 ---------------------------------------------------------------------------*/
562 struct int_tree_map GTY(())
569 extern unsigned int int_tree_map_hash (const void *);
570 extern int int_tree_map_eq (const void *, const void *);
575 } referenced_var_iterator;
578 /* This macro loops over all the referenced vars, one at a time, putting the
579 current var in VAR. Note: You are not allowed to add referenced variables
580 to the hashtable while using this macro. Doing so may cause it to behave
583 #define FOR_EACH_REFERENCED_VAR(VAR, ITER) \
584 for ((VAR) = first_referenced_var (&(ITER)); \
585 !end_referenced_vars_p (&(ITER)); \
586 (VAR) = next_referenced_var (&(ITER)))
592 } safe_referenced_var_iterator;
594 /* This macro loops over all the referenced vars, one at a time, putting the
595 current var in VAR. You are allowed to add referenced variables during the
596 execution of this macro, however, the macro will not iterate over them. It
597 requires a temporary vector of trees, VEC, whose lifetime is controlled by
598 the caller. The purpose of the vector is to temporarily store the
599 referenced_variables hashtable so that adding referenced variables does not
600 affect the hashtable. */
602 #define FOR_EACH_REFERENCED_VAR_SAFE(VAR, VEC, ITER) \
603 for ((ITER).i = 0, fill_referenced_var_vec (&(VEC)); \
604 VEC_iterate (tree, (VEC), (ITER).i, (VAR)); \
607 extern tree referenced_var_lookup (unsigned int);
608 extern bool referenced_var_check_and_insert (tree);
609 #define num_referenced_vars htab_elements (gimple_referenced_vars (cfun))
610 #define referenced_var(i) referenced_var_lookup (i)
612 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
613 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
615 /* Macros for showing usage statistics. */
616 #define SCALE(x) ((unsigned long) ((x) < 1024*10 \
618 : ((x) < 1024*1024*10 \
620 : (x) / (1024*1024))))
622 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
624 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
626 /*---------------------------------------------------------------------------
628 ---------------------------------------------------------------------------*/
631 tree_stmt_iterator tsi;
633 } block_stmt_iterator;
635 static inline block_stmt_iterator bsi_start (basic_block);
636 static inline block_stmt_iterator bsi_last (basic_block);
637 static inline block_stmt_iterator bsi_after_labels (basic_block);
638 block_stmt_iterator bsi_for_stmt (tree);
639 static inline bool bsi_end_p (block_stmt_iterator);
640 static inline void bsi_next (block_stmt_iterator *);
641 static inline void bsi_prev (block_stmt_iterator *);
642 static inline tree bsi_stmt (block_stmt_iterator);
643 static inline tree * bsi_stmt_ptr (block_stmt_iterator);
645 extern void bsi_remove (block_stmt_iterator *, bool);
646 extern void bsi_move_before (block_stmt_iterator *, block_stmt_iterator *);
647 extern void bsi_move_after (block_stmt_iterator *, block_stmt_iterator *);
648 extern void bsi_move_to_bb_end (block_stmt_iterator *, basic_block);
650 enum bsi_iterator_update
652 /* Note that these are intentionally in the same order as TSI_FOO. They
653 mean exactly the same as their TSI_* counterparts. */
661 extern void bsi_insert_before (block_stmt_iterator *, tree,
662 enum bsi_iterator_update);
663 extern void bsi_insert_after (block_stmt_iterator *, tree,
664 enum bsi_iterator_update);
666 extern void bsi_replace (const block_stmt_iterator *, tree, bool);
668 /*---------------------------------------------------------------------------
670 ---------------------------------------------------------------------------*/
672 /* Parallel region information. Every parallel and workshare
673 directive is enclosed between two markers, the OMP_* directive
674 and a corresponding OMP_RETURN statement. */
678 /* The enclosing region. */
679 struct omp_region *outer;
681 /* First child region. */
682 struct omp_region *inner;
684 /* Next peer region. */
685 struct omp_region *next;
687 /* Block containing the omp directive as its last stmt. */
690 /* Block containing the OMP_RETURN as its last stmt. */
693 /* Block containing the OMP_CONTINUE as its last stmt. */
696 /* If this is a combined parallel+workshare region, this is a list
697 of additional arguments needed by the combined parallel+workshare
701 /* The code for the omp directive of this region. */
704 /* Schedule kind, only used for OMP_FOR type regions. */
705 enum omp_clause_schedule_kind sched_kind;
707 /* True if this is a combined parallel+workshare region. */
708 bool is_combined_parallel;
711 extern struct omp_region *root_omp_region;
712 extern struct omp_region *new_omp_region (basic_block, enum tree_code,
713 struct omp_region *);
714 extern void free_omp_regions (void);
716 /*---------------------------------------------------------------------------
718 ---------------------------------------------------------------------------*/
721 /* Location to track pending stmt for edge insertion. */
722 #define PENDING_STMT(e) ((e)->insns.t)
724 extern void delete_tree_cfg_annotations (void);
725 extern void disband_implicit_edges (void);
726 extern bool stmt_ends_bb_p (tree);
727 extern bool is_ctrl_stmt (tree);
728 extern bool is_ctrl_altering_stmt (tree);
729 extern bool computed_goto_p (tree);
730 extern bool simple_goto_p (tree);
731 extern bool tree_can_make_abnormal_goto (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 debug_cfg_stats (void);
740 extern void debug_loop_ir (void);
741 extern void print_loop_ir (FILE *);
742 extern void cleanup_dead_labels (void);
743 extern void group_case_labels (void);
744 extern tree first_stmt (basic_block);
745 extern tree last_stmt (basic_block);
746 extern tree last_and_only_stmt (basic_block);
747 extern edge find_taken_edge (basic_block, tree);
748 extern basic_block label_to_block_fn (struct function *, tree);
749 #define label_to_block(t) (label_to_block_fn (cfun, t))
750 extern void bsi_insert_on_edge (edge, tree);
751 extern basic_block bsi_insert_on_edge_immediate (edge, tree);
752 extern void bsi_commit_one_edge_insert (edge, basic_block *);
753 extern void bsi_commit_edge_inserts (void);
754 extern void notice_special_calls (tree);
755 extern void clear_special_calls (void);
756 extern void verify_stmts (void);
757 extern tree tree_block_label (basic_block);
758 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
759 extern bool tree_duplicate_sese_region (edge, edge, basic_block *, unsigned,
761 extern void add_phi_args_after_copy_bb (basic_block);
762 extern void add_phi_args_after_copy (basic_block *, unsigned);
763 extern bool tree_purge_dead_abnormal_call_edges (basic_block);
764 extern bool tree_purge_dead_eh_edges (basic_block);
765 extern bool tree_purge_all_dead_eh_edges (bitmap);
766 extern tree gimplify_val (block_stmt_iterator *, tree, tree);
767 extern tree gimplify_build1 (block_stmt_iterator *, enum tree_code,
769 extern tree gimplify_build2 (block_stmt_iterator *, enum tree_code,
771 extern tree gimplify_build3 (block_stmt_iterator *, enum tree_code,
772 tree, tree, tree, tree);
773 extern void init_empty_tree_cfg (void);
774 extern void fold_cond_expr_cond (void);
775 extern void make_abnormal_goto_edges (basic_block, bool);
776 extern void replace_uses_by (tree, tree);
777 extern void start_recording_case_labels (void);
778 extern void end_recording_case_labels (void);
779 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
782 /* In tree-cfgcleanup.c */
783 extern bool cleanup_tree_cfg (void);
784 extern bool cleanup_tree_cfg_loop (void);
786 /* In tree-pretty-print.c. */
787 extern void dump_generic_bb (FILE *, basic_block, int, int);
790 extern var_ann_t create_var_ann (tree);
791 extern function_ann_t create_function_ann (tree);
792 extern stmt_ann_t create_stmt_ann (tree);
793 extern tree_ann_common_t create_tree_common_ann (tree);
794 extern void dump_dfa_stats (FILE *);
795 extern void debug_dfa_stats (void);
796 extern void debug_referenced_vars (void);
797 extern void dump_referenced_vars (FILE *);
798 extern void dump_variable (FILE *, tree);
799 extern void debug_variable (tree);
800 extern void dump_subvars_for (FILE *, tree);
801 extern void debug_subvars_for (tree);
802 extern tree get_virtual_var (tree);
803 extern void add_referenced_var (tree);
804 extern void remove_referenced_var (tree);
805 extern void mark_symbols_for_renaming (tree);
806 extern void find_new_referenced_vars (tree *);
807 extern tree make_rename_temp (tree, const char *);
808 extern void set_default_def (tree, tree);
809 extern tree gimple_default_def (struct function *, tree);
810 extern struct mem_sym_stats_d *mem_sym_stats (struct function *, tree);
812 /* In tree-phinodes.c */
813 extern void reserve_phi_args_for_new_edge (basic_block);
814 extern tree create_phi_node (tree, basic_block);
815 extern void add_phi_arg (tree, tree, edge);
816 extern void remove_phi_args (edge);
817 extern void remove_phi_node (tree, tree, bool);
818 extern tree phi_reverse (tree);
820 /* In gimple-low.c */
821 extern void record_vars_into (tree, tree);
822 extern void record_vars (tree);
823 extern bool block_may_fallthru (tree);
825 /* In tree-ssa-alias.c */
826 extern void dump_may_aliases_for (FILE *, tree);
827 extern void debug_may_aliases_for (tree);
828 extern void dump_alias_info (FILE *);
829 extern void debug_alias_info (void);
830 extern void dump_points_to_info (FILE *);
831 extern void debug_points_to_info (void);
832 extern void dump_points_to_info_for (FILE *, tree);
833 extern void debug_points_to_info_for (tree);
834 extern bool may_be_aliased (tree);
835 extern bool is_aliased_with (tree, tree);
836 extern struct ptr_info_def *get_ptr_info (tree);
837 extern void new_type_alias (tree, tree, tree);
838 extern void count_uses_and_derefs (tree, tree, unsigned *, unsigned *,
840 static inline subvar_t get_subvars_for_var (tree);
841 static inline tree get_subvar_at (tree, unsigned HOST_WIDE_INT);
842 static inline bool ref_contains_array_ref (tree);
843 static inline bool array_ref_contains_indirect_ref (tree);
844 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
845 HOST_WIDE_INT *, HOST_WIDE_INT *);
846 static inline bool var_can_have_subvars (tree);
847 static inline bool overlap_subvar (unsigned HOST_WIDE_INT,
848 unsigned HOST_WIDE_INT,
850 extern tree create_tag_raw (enum tree_code, tree, const char *);
851 extern void delete_mem_ref_stats (struct function *);
852 extern void dump_mem_ref_stats (FILE *);
853 extern void debug_mem_ref_stats (void);
854 extern void debug_memory_partitions (void);
855 extern void debug_mem_sym_stats (tree var);
856 extern void debug_all_mem_sym_stats (void);
858 /* Call-back function for walk_use_def_chains(). At each reaching
859 definition, a function with this prototype is called. */
860 typedef bool (*walk_use_def_chains_fn) (tree, tree, void *);
864 extern void init_tree_ssa (void);
865 extern edge ssa_redirect_edge (edge, basic_block);
866 extern void flush_pending_stmts (edge);
867 extern bool tree_ssa_useless_type_conversion (tree);
868 extern bool tree_ssa_useless_type_conversion_1 (tree, tree);
869 extern void verify_ssa (bool);
870 extern void delete_tree_ssa (void);
871 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
872 extern bool stmt_references_memory_p (tree);
874 /* In tree-into-ssa.c */
875 void update_ssa (unsigned);
876 void delete_update_ssa (void);
877 void register_new_name_mapping (tree, tree);
878 tree create_new_def_for (tree, tree, def_operand_p);
879 bool need_ssa_update_p (void);
880 bool name_mappings_registered_p (void);
881 bool name_registered_for_update_p (tree);
882 bitmap ssa_names_to_replace (void);
883 void release_ssa_name_after_update_ssa (tree);
884 void compute_global_livein (bitmap, bitmap);
885 tree duplicate_ssa_name (tree, tree);
886 void mark_sym_for_renaming (tree);
887 void mark_set_for_renaming (bitmap);
888 tree get_current_def (tree);
889 void set_current_def (tree, tree);
891 /* In tree-ssa-ccp.c */
892 bool fold_stmt (tree *);
893 bool fold_stmt_inplace (tree);
894 tree widen_bitfield (tree, tree, tree);
897 tree vrp_evaluate_conditional (tree, tree);
898 void simplify_stmt_using_ranges (tree);
900 /* In tree-ssa-dom.c */
901 extern void dump_dominator_optimization_stats (FILE *);
902 extern void debug_dominator_optimization_stats (void);
903 int loop_depth_of_name (tree);
905 /* In tree-ssa-copy.c */
906 extern void merge_alias_info (tree, tree);
907 extern void propagate_value (use_operand_p, tree);
908 extern void propagate_tree_value (tree *, tree);
909 extern void replace_exp (use_operand_p, tree);
910 extern bool may_propagate_copy (tree, tree);
911 extern bool may_propagate_copy_into_asm (tree);
917 /* Iv = BASE + STEP * i. */
920 /* True if this iv does not overflow. */
924 /* Description of number of iterations of a loop. All the expressions inside
925 the structure can be evaluated at the end of the loop's preheader
926 (and due to ssa form, also anywhere inside the body of the loop). */
928 struct tree_niter_desc
930 tree assumptions; /* The boolean expression. If this expression evaluates
931 to false, then the other fields in this structure
932 should not be used; there is no guarantee that they
934 tree may_be_zero; /* The boolean expression. If it evaluates to true,
935 the loop will exit in the first iteration (i.e.
936 its latch will not be executed), even if the niter
937 field says otherwise. */
938 tree niter; /* The expression giving the number of iterations of
939 a loop (provided that assumptions == true and
940 may_be_zero == false), more precisely the number
941 of executions of the latch of the loop. */
942 double_int max; /* The upper bound on the number of iterations of
945 /* The simplified shape of the exit condition. The loop exits if
946 CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
947 LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
948 LE_EXPR and negative if CMP is GE_EXPR. This information is used
949 by loop unrolling. */
955 /* In tree-vectorizer.c */
956 unsigned vectorize_loops (void);
957 extern bool vect_can_force_dr_alignment_p (tree, unsigned int);
958 extern tree get_vectype_for_scalar_type (tree);
960 /* In tree-ssa-phiopt.c */
961 bool empty_block_p (basic_block);
963 /* In tree-ssa-loop*.c */
965 void tree_ssa_lim (void);
966 unsigned int tree_ssa_unswitch_loops (void);
967 unsigned int canonicalize_induction_variables (void);
968 unsigned int tree_unroll_loops_completely (bool);
969 unsigned int tree_ssa_prefetch_arrays (void);
970 unsigned int remove_empty_loops (void);
971 void tree_ssa_iv_optimize (void);
973 bool number_of_iterations_exit (struct loop *, edge,
974 struct tree_niter_desc *niter, bool);
975 tree find_loop_niter (struct loop *, edge *);
976 tree loop_niter_by_eval (struct loop *, edge);
977 tree find_loop_niter_by_eval (struct loop *, edge *);
978 void estimate_numbers_of_iterations (void);
979 bool scev_probably_wraps_p (tree, tree, tree, struct loop *, bool);
980 bool convert_affine_scev (struct loop *, tree, tree *, tree *, tree, bool);
982 bool nowrap_type_p (tree);
983 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
984 enum ev_direction scev_direction (tree);
986 void free_numbers_of_iterations_estimates (void);
987 void free_numbers_of_iterations_estimates_loop (struct loop *);
988 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
989 void verify_loop_closed_ssa (void);
990 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
991 void create_iv (tree, tree, tree, struct loop *, block_stmt_iterator *, bool,
993 void split_loop_exit_edge (edge);
994 unsigned force_expr_to_var_cost (tree);
995 void standard_iv_increment_position (struct loop *, block_stmt_iterator *,
997 basic_block ip_end_pos (struct loop *);
998 basic_block ip_normal_pos (struct loop *);
999 bool tree_duplicate_loop_to_header_edge (struct loop *, edge,
1000 unsigned int, sbitmap,
1001 edge, VEC (edge, heap) **,
1003 struct loop *tree_ssa_loop_version (struct loop *, tree,
1005 tree expand_simple_operations (tree);
1006 void substitute_in_loop_info (struct loop *, tree, tree);
1007 edge single_dom_exit (struct loop *);
1008 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
1009 struct tree_niter_desc *niter);
1010 void tree_unroll_loop (struct loop *, unsigned,
1011 edge, struct tree_niter_desc *);
1012 typedef void (*transform_callback)(struct loop *, void *);
1013 void tree_transform_and_unroll_loop (struct loop *, unsigned,
1014 edge, struct tree_niter_desc *,
1015 transform_callback, void *);
1016 bool contains_abnormal_ssa_name_p (tree);
1018 /* In tree-ssa-threadedge.c */
1019 extern bool potentially_threadable_block (basic_block);
1020 extern void thread_across_edge (tree, edge, bool,
1021 VEC(tree, heap) **, tree (*) (tree, tree));
1023 /* In tree-ssa-loop-im.c */
1024 /* The possibilities of statement movement. */
1028 MOVE_IMPOSSIBLE, /* No movement -- side effect expression. */
1029 MOVE_PRESERVE_EXECUTION, /* Must not cause the non-executed statement
1030 become executed -- memory accesses, ... */
1031 MOVE_POSSIBLE /* Unlimited movement. */
1033 extern enum move_pos movement_possibility (tree);
1035 /* The reasons a variable may escape a function. */
1038 NO_ESCAPE = 0, /* Doesn't escape. */
1039 ESCAPE_STORED_IN_GLOBAL = 1 << 1,
1040 ESCAPE_TO_ASM = 1 << 2, /* Passed by address to an assembly
1042 ESCAPE_TO_CALL = 1 << 3, /* Escapes to a function call. */
1043 ESCAPE_BAD_CAST = 1 << 4, /* Cast from pointer to integer */
1044 ESCAPE_TO_RETURN = 1 << 5, /* Returned from function. */
1045 ESCAPE_TO_PURE_CONST = 1 << 6, /* Escapes to a pure or constant
1047 ESCAPE_IS_GLOBAL = 1 << 7, /* Is a global variable. */
1048 ESCAPE_IS_PARM = 1 << 8, /* Is an incoming function argument. */
1049 ESCAPE_UNKNOWN = 1 << 9 /* We believe it escapes for
1050 some reason not enumerated
1054 /* In tree-flow-inline.h */
1055 static inline bool is_call_clobbered (tree);
1056 static inline void mark_call_clobbered (tree, unsigned int);
1057 static inline void set_is_used (tree);
1058 static inline bool unmodifiable_var_p (tree);
1061 extern void make_eh_edges (tree);
1062 extern bool tree_could_trap_p (tree);
1063 extern bool tree_could_throw_p (tree);
1064 extern bool tree_can_throw_internal (tree);
1065 extern bool tree_can_throw_external (tree);
1066 extern int lookup_stmt_eh_region (tree);
1067 extern void add_stmt_to_eh_region (tree, int);
1068 extern bool remove_stmt_from_eh_region (tree);
1069 extern bool maybe_clean_or_replace_eh_stmt (tree, tree);
1071 /* In tree-ssa-pre.c */
1072 void add_to_value (tree, tree);
1073 void debug_value_expressions (tree);
1074 void print_value_expressions (FILE *, tree);
1078 bool expressions_equal_p (tree, tree);
1079 static inline tree get_value_handle (tree);
1080 hashval_t vn_compute (tree, hashval_t);
1081 void sort_vuses (VEC (tree, gc) *);
1082 tree vn_lookup_or_add (tree, tree);
1083 tree vn_lookup_or_add_with_vuses (tree, VEC (tree, gc) *);
1084 void vn_add (tree, tree);
1085 void vn_add_with_vuses (tree, tree, VEC (tree, gc) *);
1086 tree vn_lookup (tree, tree);
1087 tree vn_lookup_with_vuses (tree, VEC (tree, gc) *);
1088 void vn_init (void);
1089 void vn_delete (void);
1091 /* In tree-ssa-sink.c */
1092 bool is_hidden_global_store (tree);
1095 void insert_edge_copies (tree, basic_block);
1096 void sra_insert_before (block_stmt_iterator *, tree);
1097 void sra_insert_after (block_stmt_iterator *, tree);
1098 void sra_init_cache (void);
1099 bool sra_type_can_be_decomposed_p (tree);
1101 /* In tree-loop-linear.c */
1102 extern void linear_transform_loops (void);
1104 /* In tree-data-ref.c */
1105 extern void tree_check_data_deps (void);
1107 /* In tree-ssa-loop-ivopts.c */
1108 bool expr_invariant_in_loop_p (struct loop *, tree);
1109 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode);
1110 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode);
1112 /* In tree-ssa-threadupdate.c. */
1113 extern bool thread_through_all_blocks (void);
1114 extern void register_jump_thread (edge, edge);
1117 tree force_gimple_operand (tree, tree *, bool, tree);
1118 tree force_gimple_operand_bsi (block_stmt_iterator *, tree, bool, tree);
1120 /* In tree-ssa-structalias.c */
1121 bool find_what_p_points_to (tree);
1123 /* In tree-ssa-live.c */
1124 extern void remove_unused_locals (void);
1126 /* In tree-ssa-address.c */
1128 /* Description of a memory address. */
1132 tree symbol, base, index, step, offset;
1135 struct affine_tree_combination;
1136 tree create_mem_ref (block_stmt_iterator *, tree,
1137 struct affine_tree_combination *);
1138 rtx addr_for_mem_ref (struct mem_address *, bool);
1139 void get_address_description (tree, struct mem_address *);
1140 tree maybe_fold_tmr (tree);
1142 /* This structure is simply used during pushing fields onto the fieldstack
1143 to track the offset of the field, since bitpos_of_field gives it relative
1144 to its immediate containing type, and we want it relative to the ultimate
1145 containing object. */
1152 HOST_WIDE_INT offset;
1154 typedef struct fieldoff fieldoff_s;
1156 DEF_VEC_O(fieldoff_s);
1157 DEF_VEC_ALLOC_O(fieldoff_s,heap);
1158 int push_fields_onto_fieldstack (tree, VEC(fieldoff_s,heap) **,
1159 HOST_WIDE_INT, bool *);
1160 void sort_fieldstack (VEC(fieldoff_s,heap) *);
1162 void init_alias_heapvars (void);
1163 void delete_alias_heapvars (void);
1164 unsigned int execute_fixup_cfg (void);
1166 #include "tree-flow-inline.h"
1168 void swap_tree_operands (tree, tree *, tree *);
1170 int least_common_multiple (int, int);
1172 #endif /* _TREE_FLOW_H */