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 /* Gimple dataflow datastructure. All publicly available fields shall have
45 gimple_ accessor defined in tree-flow-inline.h, all publicly modifiable
46 fields should have gimple_set accessor. */
47 struct gimple_df GTY(()) {
48 /* Array of all variables referenced in the function. */
49 htab_t GTY((param_is (struct int_tree_map))) referenced_vars;
51 /* A list of all the noreturn calls passed to modify_stmt.
52 cleanup_control_flow uses it to detect cases where a mid-block
53 indirect call has been turned into a noreturn call. When this
54 happens, all the instructions after the call are no longer
55 reachable and must be deleted as dead. */
56 VEC(tree,gc) *modified_noreturn_calls;
58 /* Array of all SSA_NAMEs used in the function. */
59 VEC(tree,gc) *ssa_names;
61 /* Artificial variable used to model the effects of function calls. */
64 /* Artificial variable used to model the effects of nonlocal
68 /* Call clobbered variables in the function. If bit I is set, then
69 REFERENCED_VARS (I) is call-clobbered. */
70 bitmap call_clobbered_vars;
72 /* Addressable variables in the function. If bit I is set, then
73 REFERENCED_VARS (I) has had its address taken. Note that
74 CALL_CLOBBERED_VARS and ADDRESSABLE_VARS are not related. An
75 addressable variable is not necessarily call-clobbered (e.g., a
76 local addressable whose address does not escape) and not all
77 call-clobbered variables are addressable (e.g., a local static
79 bitmap addressable_vars;
81 /* Free list of SSA_NAMEs. */
84 /* Hashtable holding definition for symbol. If this field is not NULL, it
85 means that the first reference to this variable in the function is a
86 USE or a VUSE. In those cases, the SSA renamer creates an SSA name
87 for this variable with an empty defining statement. */
88 htab_t GTY((param_is (struct int_tree_map))) default_defs;
90 /* 'true' after aliases have been computed (see compute_may_aliases). */
91 unsigned int aliases_computed_p : 1;
93 /* True if the code is in ssa form. */
94 unsigned int in_ssa_p : 1;
96 struct ssa_operands ssa_operands;
98 /* Hashtable of variables annotations. Used for static variables only;
99 local variables have direct pointer in the tree node. */
100 htab_t GTY((param_is (struct static_var_ann_d))) var_anns;
103 /* Accessors for internal use only. Generic code should use abstraction
104 provided by tree-flow-inline.h or specific modules. */
105 #define FREE_SSANAMES(fun) (fun)->gimple_df->free_ssanames
106 #define SSANAMES(fun) (fun)->gimple_df->ssa_names
107 #define MODIFIED_NORETURN_CALLS(fun) (fun)->gimple_df->modified_noreturn_calls
108 #define DEFAULT_DEFS(fun) (fun)->gimple_df->default_defs
117 /* Iterate through the elements of hashtable HTAB, using htab_iterator ITER,
118 storing each element in RESULT, which is of type TYPE. */
119 #define FOR_EACH_HTAB_ELEMENT(HTAB, RESULT, TYPE, ITER) \
120 for (RESULT = (TYPE) first_htab_element (&(ITER), (HTAB)); \
121 !end_htab_p (&(ITER)); \
122 RESULT = (TYPE) next_htab_element (&(ITER)))
124 /*---------------------------------------------------------------------------
125 Attributes for SSA_NAMEs.
127 NOTE: These structures are stored in struct tree_ssa_name
128 but are only used by the tree optimizers, so it makes better sense
129 to declare them here to avoid recompiling unrelated files when
131 ---------------------------------------------------------------------------*/
133 /* Aliasing information for SSA_NAMEs representing pointer variables. */
134 struct ptr_info_def GTY(())
136 /* Nonzero if points-to analysis couldn't determine where this pointer
138 unsigned int pt_anything : 1;
140 /* Nonzero if the value of this pointer escapes the current function. */
141 unsigned int value_escapes_p : 1;
143 /* Nonzero if this pointer is dereferenced. */
144 unsigned int is_dereferenced : 1;
146 /* Nonzero if this pointer points to a global variable. */
147 unsigned int pt_global_mem : 1;
149 /* Nonzero if this pointer points to NULL. */
150 unsigned int pt_null : 1;
152 /* Set of variables that this pointer may point to. */
155 /* If this pointer has been dereferenced, and points-to information is
156 more precise than type-based aliasing, indirect references to this
157 pointer will be represented by this memory tag, instead of the type
158 tag computed by TBAA. */
161 /* Mask of reasons this pointer's value escapes the function */
162 unsigned int escape_mask;
166 /*---------------------------------------------------------------------------
167 Tree annotations stored in tree_base.ann
168 ---------------------------------------------------------------------------*/
169 enum tree_ann_type { TREE_ANN_COMMON, VAR_ANN, FUNCTION_ANN, STMT_ANN };
171 struct tree_ann_common_d GTY(())
173 /* Annotation type. */
174 enum tree_ann_type type;
176 /* Auxiliary info specific to a pass. At all times, this
177 should either point to valid data or be NULL. */
178 PTR GTY ((skip (""))) aux;
180 /* The value handle for this expression. Used by GVN-PRE. */
181 tree GTY((skip)) value_handle;
184 /* It is advantageous to avoid things like life analysis for variables which
185 do not need PHI nodes. This enum describes whether or not a particular
186 variable may need a PHI node. */
188 enum need_phi_state {
189 /* This is the default. If we are still in this state after finding
190 all the definition and use sites, then we will assume the variable
191 needs PHI nodes. This is probably an overly conservative assumption. */
192 NEED_PHI_STATE_UNKNOWN,
194 /* This state indicates that we have seen one or more sets of the
195 variable in a single basic block and that the sets dominate all
196 uses seen so far. If after finding all definition and use sites
197 we are still in this state, then the variable does not need any
201 /* This state indicates that we have either seen multiple definitions of
202 the variable in multiple blocks, or that we encountered a use in a
203 block that was not dominated by the block containing the set(s) of
204 this variable. This variable is assumed to need PHI nodes. */
209 typedef struct subvar *subvar_t;
211 /* This structure represents a fake sub-variable for a structure field. */
212 struct subvar GTY(())
217 /* Next subvar for this structure. */
221 struct var_ann_d GTY(())
223 struct tree_ann_common_d common;
225 /* Used by the out of SSA pass to determine whether this variable has
226 been seen yet or not. */
227 unsigned out_of_ssa_tag : 1;
229 /* Used when building base variable structures in a var_map. */
230 unsigned base_var_processed : 1;
232 /* Nonzero if this variable was used after SSA optimizations were
233 applied. We set this when translating out of SSA form. */
236 /* This field indicates whether or not the variable may need PHI nodes.
237 See the enum's definition for more detailed information about the
239 ENUM_BITFIELD (need_phi_state) need_phi_state : 2;
241 /* Used during operand processing to determine if this variable is already
243 unsigned in_vuse_list : 1;
245 /* Used during operand processing to determine if this variable is already
247 unsigned in_vdef_list : 1;
249 /* True for HEAP and PARM_NOALIAS artificial variables. */
250 unsigned is_heapvar : 1;
252 /* True if the variable is call clobbered. */
253 unsigned int call_clobbered : 1;
255 /* Memory partition tag assigned to this symbol. */
258 /* If this variable is a pointer P that has been dereferenced, this
259 field is an artificial variable that represents the memory
260 location *P. Every other pointer Q that is type-compatible with
261 P will also have the same memory tag. If the variable is not a
262 pointer or if it is never dereferenced, this must be NULL.
263 FIXME, do we really need this here? How much slower would it be
264 to convert to hash table? */
267 /* Used when going out of SSA form to indicate which partition this
268 variable represents storage for. */
271 /* Used by var_map for the base index of ssa base variables. */
274 /* During into-ssa and the dominator optimizer, this field holds the
275 current version of this variable (an SSA_NAME). */
278 /* If this variable is a structure, this fields holds a list of
279 symbols representing each of the fields of the structure. */
282 /* Mask of values saying the reasons why this variable has escaped
284 unsigned int escape_mask;
287 /* Container for variable annotation used by hashtable for annotations for
289 struct static_var_ann_d GTY(())
291 struct var_ann_d ann;
295 struct function_ann_d GTY(())
297 struct tree_ann_common_d common;
299 /* Pointer to the structure that contains the sets of global
300 variables modified by function calls. This field is only used
301 for FUNCTION_DECLs. */
302 ipa_reference_vars_info_t GTY ((skip)) reference_vars_info;
305 typedef struct immediate_use_iterator_d
307 /* This is the current use the iterator is processing. */
308 ssa_use_operand_t *imm_use;
309 /* This marks the last use in the list (use node from SSA_NAME) */
310 ssa_use_operand_t *end_p;
311 /* This node is inserted and used to mark the end of the uses for a stmt. */
312 ssa_use_operand_t iter_node;
313 /* This is the next ssa_name to visit. IMM_USE may get removed before
314 the next one is traversed to, so it must be cached early. */
315 ssa_use_operand_t *next_imm_name;
319 /* Use this iterator when simply looking at stmts. Adding, deleting or
320 modifying stmts will cause this iterator to malfunction. */
322 #define FOR_EACH_IMM_USE_FAST(DEST, ITER, SSAVAR) \
323 for ((DEST) = first_readonly_imm_use (&(ITER), (SSAVAR)); \
324 !end_readonly_imm_use_p (&(ITER)); \
325 (DEST) = next_readonly_imm_use (&(ITER)))
327 /* Use this iterator to visit each stmt which has a use of SSAVAR. */
329 #define FOR_EACH_IMM_USE_STMT(STMT, ITER, SSAVAR) \
330 for ((STMT) = first_imm_use_stmt (&(ITER), (SSAVAR)); \
331 !end_imm_use_stmt_p (&(ITER)); \
332 (STMT) = next_imm_use_stmt (&(ITER)))
334 /* Use this to terminate the FOR_EACH_IMM_USE_STMT loop early. Failure to
335 do so will result in leaving a iterator marker node in the immediate
336 use list, and nothing good will come from that. */
337 #define BREAK_FROM_IMM_USE_STMT(ITER) \
339 end_imm_use_stmt_traverse (&(ITER)); \
344 /* Use this iterator in combination with FOR_EACH_IMM_USE_STMT to
345 get access to each occurrence of ssavar on the stmt returned by
346 that iterator.. for instance:
348 FOR_EACH_IMM_USE_STMT (stmt, iter, var)
350 FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
352 SET_USE (use_p) = blah;
357 #define FOR_EACH_IMM_USE_ON_STMT(DEST, ITER) \
358 for ((DEST) = first_imm_use_on_stmt (&(ITER)); \
359 !end_imm_use_on_stmt_p (&(ITER)); \
360 (DEST) = next_imm_use_on_stmt (&(ITER)))
364 struct stmt_ann_d GTY(())
366 struct tree_ann_common_d common;
368 /* Basic block that contains this statement. */
371 /* Operand cache for stmt. */
372 struct stmt_operands_d GTY ((skip (""))) operands;
374 /* Set of variables that have had their address taken in the statement. */
375 bitmap addresses_taken;
377 /* Unique identifier for this statement. These ID's are to be created
378 by each pass on an as-needed basis in any order convenient for the
379 pass which needs statement UIDs. */
382 /* Nonzero if the statement references memory (at least one of its
383 expressions contains a non-register operand). */
384 unsigned references_memory : 1;
386 /* Nonzero if the statement has been modified (meaning that the operands
387 need to be scanned again). */
388 unsigned modified : 1;
390 /* Nonzero if the statement makes references to volatile storage. */
391 unsigned has_volatile_ops : 1;
393 /* Nonzero if the statement makes a function call that may clobber global
394 and local addressable variables. */
395 unsigned makes_clobbering_call : 1;
398 union tree_ann_d GTY((desc ("ann_type ((tree_ann_t)&%h)")))
400 struct tree_ann_common_d GTY((tag ("TREE_ANN_COMMON"))) common;
401 struct var_ann_d GTY((tag ("VAR_ANN"))) vdecl;
402 struct function_ann_d GTY((tag ("FUNCTION_ANN"))) fdecl;
403 struct stmt_ann_d GTY((tag ("STMT_ANN"))) stmt;
406 typedef union tree_ann_d *tree_ann_t;
407 typedef struct var_ann_d *var_ann_t;
408 typedef struct function_ann_d *function_ann_t;
409 typedef struct stmt_ann_d *stmt_ann_t;
410 typedef struct tree_ann_common_d *tree_ann_common_t;
412 static inline tree_ann_common_t tree_common_ann (tree);
413 static inline tree_ann_common_t get_tree_common_ann (tree);
414 static inline var_ann_t var_ann (tree);
415 static inline var_ann_t get_var_ann (tree);
416 static inline function_ann_t function_ann (tree);
417 static inline function_ann_t get_function_ann (tree);
418 static inline stmt_ann_t stmt_ann (tree);
419 static inline bool has_stmt_ann (tree);
420 static inline stmt_ann_t get_stmt_ann (tree);
421 static inline enum tree_ann_type ann_type (tree_ann_t);
422 static inline basic_block bb_for_stmt (tree);
423 extern void set_bb_for_stmt (tree, basic_block);
424 static inline bool noreturn_call_p (tree);
425 static inline void update_stmt (tree);
426 static inline bool stmt_modified_p (tree);
427 static inline bitmap may_aliases (tree);
428 static inline int get_lineno (tree);
429 static inline const char *get_filename (tree);
430 static inline bool is_exec_stmt (tree);
431 static inline bool is_label_stmt (tree);
432 static inline bitmap addresses_taken (tree);
434 /*---------------------------------------------------------------------------
435 Structure representing predictions in tree level.
436 ---------------------------------------------------------------------------*/
437 struct edge_prediction GTY((chain_next ("%h.ep_next")))
439 struct edge_prediction *ep_next;
441 enum br_predictor ep_predictor;
445 /* Accessors for basic block annotations. */
446 static inline tree phi_nodes (basic_block);
447 static inline void set_phi_nodes (basic_block, tree);
449 /*---------------------------------------------------------------------------
451 ---------------------------------------------------------------------------*/
452 struct int_tree_map GTY(())
459 extern unsigned int int_tree_map_hash (const void *);
460 extern int int_tree_map_eq (const void *, const void *);
465 } referenced_var_iterator;
468 /* This macro loops over all the referenced vars, one at a time, putting the
469 current var in VAR. Note: You are not allowed to add referenced variables
470 to the hashtable while using this macro. Doing so may cause it to behave
473 #define FOR_EACH_REFERENCED_VAR(VAR, ITER) \
474 for ((VAR) = first_referenced_var (&(ITER)); \
475 !end_referenced_vars_p (&(ITER)); \
476 (VAR) = next_referenced_var (&(ITER)))
482 } safe_referenced_var_iterator;
484 /* This macro loops over all the referenced vars, one at a time, putting the
485 current var in VAR. You are allowed to add referenced variables during the
486 execution of this macro, however, the macro will not iterate over them. It
487 requires a temporary vector of trees, VEC, whose lifetime is controlled by
488 the caller. The purpose of the vector is to temporarily store the
489 referenced_variables hashtable so that adding referenced variables does not
490 affect the hashtable. */
492 #define FOR_EACH_REFERENCED_VAR_SAFE(VAR, VEC, ITER) \
493 for ((ITER).i = 0, fill_referenced_var_vec (&(VEC)); \
494 VEC_iterate (tree, (VEC), (ITER).i, (VAR)); \
497 extern tree referenced_var_lookup (unsigned int);
498 extern bool referenced_var_check_and_insert (tree);
499 #define num_referenced_vars htab_elements (gimple_referenced_vars (cfun))
500 #define referenced_var(i) referenced_var_lookup (i)
502 #define num_ssa_names (VEC_length (tree, cfun->gimple_df->ssa_names))
503 #define ssa_name(i) (VEC_index (tree, cfun->gimple_df->ssa_names, (i)))
505 /* Macros for showing usage statistics. */
506 #define SCALE(x) ((unsigned long) ((x) < 1024*10 \
508 : ((x) < 1024*1024*10 \
510 : (x) / (1024*1024))))
512 #define LABEL(x) ((x) < 1024*10 ? 'b' : ((x) < 1024*1024*10 ? 'k' : 'M'))
514 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
516 /*---------------------------------------------------------------------------
518 ---------------------------------------------------------------------------*/
521 tree_stmt_iterator tsi;
523 } block_stmt_iterator;
525 static inline block_stmt_iterator bsi_start (basic_block);
526 static inline block_stmt_iterator bsi_last (basic_block);
527 static inline block_stmt_iterator bsi_after_labels (basic_block);
528 block_stmt_iterator bsi_for_stmt (tree);
529 static inline bool bsi_end_p (block_stmt_iterator);
530 static inline void bsi_next (block_stmt_iterator *);
531 static inline void bsi_prev (block_stmt_iterator *);
532 static inline tree bsi_stmt (block_stmt_iterator);
533 static inline tree * bsi_stmt_ptr (block_stmt_iterator);
535 extern void bsi_remove (block_stmt_iterator *, bool);
536 extern void bsi_move_before (block_stmt_iterator *, block_stmt_iterator *);
537 extern void bsi_move_after (block_stmt_iterator *, block_stmt_iterator *);
538 extern void bsi_move_to_bb_end (block_stmt_iterator *, basic_block);
540 enum bsi_iterator_update
542 /* Note that these are intentionally in the same order as TSI_FOO. They
543 mean exactly the same as their TSI_* counterparts. */
551 extern void bsi_insert_before (block_stmt_iterator *, tree,
552 enum bsi_iterator_update);
553 extern void bsi_insert_after (block_stmt_iterator *, tree,
554 enum bsi_iterator_update);
556 extern void bsi_replace (const block_stmt_iterator *, tree, bool);
558 /*---------------------------------------------------------------------------
560 ---------------------------------------------------------------------------*/
562 /* Parallel region information. Every parallel and workshare
563 directive is enclosed between two markers, the OMP_* directive
564 and a corresponding OMP_RETURN statement. */
568 /* The enclosing region. */
569 struct omp_region *outer;
571 /* First child region. */
572 struct omp_region *inner;
574 /* Next peer region. */
575 struct omp_region *next;
577 /* Block containing the omp directive as its last stmt. */
580 /* Block containing the OMP_RETURN as its last stmt. */
583 /* Block containing the OMP_CONTINUE as its last stmt. */
586 /* If this is a combined parallel+workshare region, this is a list
587 of additional arguments needed by the combined parallel+workshare
591 /* The code for the omp directive of this region. */
594 /* Schedule kind, only used for OMP_FOR type regions. */
595 enum omp_clause_schedule_kind sched_kind;
597 /* True if this is a combined parallel+workshare region. */
598 bool is_combined_parallel;
601 extern struct omp_region *root_omp_region;
602 extern struct omp_region *new_omp_region (basic_block, enum tree_code,
603 struct omp_region *);
604 extern void free_omp_regions (void);
606 /*---------------------------------------------------------------------------
608 ---------------------------------------------------------------------------*/
611 /* Location to track pending stmt for edge insertion. */
612 #define PENDING_STMT(e) ((e)->insns.t)
614 extern void delete_tree_cfg_annotations (void);
615 extern void disband_implicit_edges (void);
616 extern bool stmt_ends_bb_p (tree);
617 extern bool is_ctrl_stmt (tree);
618 extern bool is_ctrl_altering_stmt (tree);
619 extern bool computed_goto_p (tree);
620 extern bool simple_goto_p (tree);
621 extern bool tree_can_make_abnormal_goto (tree);
622 extern basic_block single_noncomplex_succ (basic_block bb);
623 extern void tree_dump_bb (basic_block, FILE *, int);
624 extern void debug_tree_bb (basic_block);
625 extern basic_block debug_tree_bb_n (int);
626 extern void dump_tree_cfg (FILE *, int);
627 extern void debug_tree_cfg (int);
628 extern void dump_cfg_stats (FILE *);
629 extern void debug_cfg_stats (void);
630 extern void debug_loop_ir (void);
631 extern void print_loop_ir (FILE *);
632 extern void cleanup_dead_labels (void);
633 extern void group_case_labels (void);
634 extern tree first_stmt (basic_block);
635 extern tree last_stmt (basic_block);
636 extern tree last_and_only_stmt (basic_block);
637 extern edge find_taken_edge (basic_block, tree);
638 extern basic_block label_to_block_fn (struct function *, tree);
639 #define label_to_block(t) (label_to_block_fn (cfun, t))
640 extern void bsi_insert_on_edge (edge, tree);
641 extern basic_block bsi_insert_on_edge_immediate (edge, tree);
642 extern void bsi_commit_one_edge_insert (edge, basic_block *);
643 extern void bsi_commit_edge_inserts (void);
644 extern void notice_special_calls (tree);
645 extern void clear_special_calls (void);
646 extern void verify_stmts (void);
647 extern tree tree_block_label (basic_block);
648 extern void extract_true_false_edges_from_block (basic_block, edge *, edge *);
649 extern bool tree_duplicate_sese_region (edge, edge, basic_block *, unsigned,
651 extern void add_phi_args_after_copy_bb (basic_block);
652 extern void add_phi_args_after_copy (basic_block *, unsigned);
653 extern bool tree_purge_dead_abnormal_call_edges (basic_block);
654 extern bool tree_purge_dead_eh_edges (basic_block);
655 extern bool tree_purge_all_dead_eh_edges (bitmap);
656 extern tree gimplify_val (block_stmt_iterator *, tree, tree);
657 extern tree gimplify_build1 (block_stmt_iterator *, enum tree_code,
659 extern tree gimplify_build2 (block_stmt_iterator *, enum tree_code,
661 extern tree gimplify_build3 (block_stmt_iterator *, enum tree_code,
662 tree, tree, tree, tree);
663 extern void init_empty_tree_cfg (void);
664 extern void fold_cond_expr_cond (void);
665 extern void make_abnormal_goto_edges (basic_block, bool);
666 extern void replace_uses_by (tree, tree);
667 extern void start_recording_case_labels (void);
668 extern void end_recording_case_labels (void);
669 extern basic_block move_sese_region_to_fn (struct function *, basic_block,
672 /* In tree-cfgcleanup.c */
673 extern bool cleanup_tree_cfg (void);
674 extern bool cleanup_tree_cfg_loop (void);
676 /* In tree-pretty-print.c. */
677 extern void dump_generic_bb (FILE *, basic_block, int, int);
680 extern var_ann_t create_var_ann (tree);
681 extern function_ann_t create_function_ann (tree);
682 extern stmt_ann_t create_stmt_ann (tree);
683 extern tree_ann_common_t create_tree_common_ann (tree);
684 extern void dump_dfa_stats (FILE *);
685 extern void debug_dfa_stats (void);
686 extern void debug_referenced_vars (void);
687 extern void dump_referenced_vars (FILE *);
688 extern void dump_variable (FILE *, tree);
689 extern void debug_variable (tree);
690 extern void dump_subvars_for (FILE *, tree);
691 extern void debug_subvars_for (tree);
692 extern tree get_virtual_var (tree);
693 extern void add_referenced_var (tree);
694 extern void remove_referenced_var (tree);
695 extern void mark_symbols_for_renaming (tree);
696 extern void find_new_referenced_vars (tree *);
698 extern tree make_rename_temp (tree, const char *);
699 extern void set_default_def (tree, tree);
700 extern tree gimple_default_def (struct function *, tree);
702 /* In tree-phinodes.c */
703 extern void reserve_phi_args_for_new_edge (basic_block);
704 extern tree create_phi_node (tree, basic_block);
705 extern void add_phi_arg (tree, tree, edge);
706 extern void remove_phi_args (edge);
707 extern void remove_phi_node (tree, tree, bool);
708 extern tree phi_reverse (tree);
710 /* In gimple-low.c */
711 extern void record_vars_into (tree, tree);
712 extern void record_vars (tree);
713 extern bool block_may_fallthru (tree);
715 /* In tree-ssa-alias.c */
716 extern void dump_may_aliases_for (FILE *, tree);
717 extern void debug_may_aliases_for (tree);
718 extern void dump_alias_info (FILE *);
719 extern void debug_alias_info (void);
720 extern void dump_points_to_info (FILE *);
721 extern void debug_points_to_info (void);
722 extern void dump_points_to_info_for (FILE *, tree);
723 extern void debug_points_to_info_for (tree);
724 extern bool may_be_aliased (tree);
725 extern bool is_aliased_with (tree, tree);
726 extern struct ptr_info_def *get_ptr_info (tree);
727 extern void new_type_alias (tree, tree, tree);
728 extern void count_uses_and_derefs (tree, tree, unsigned *, unsigned *, bool *);
729 static inline subvar_t get_subvars_for_var (tree);
730 static inline tree get_subvar_at (tree, unsigned HOST_WIDE_INT);
731 static inline bool ref_contains_array_ref (tree);
732 static inline bool array_ref_contains_indirect_ref (tree);
733 extern tree get_ref_base_and_extent (tree, HOST_WIDE_INT *,
734 HOST_WIDE_INT *, HOST_WIDE_INT *);
735 static inline bool var_can_have_subvars (tree);
736 static inline bool overlap_subvar (unsigned HOST_WIDE_INT,
737 unsigned HOST_WIDE_INT,
739 extern tree create_tag_raw (enum tree_code, tree, const char *);
741 /* Call-back function for walk_use_def_chains(). At each reaching
742 definition, a function with this prototype is called. */
743 typedef bool (*walk_use_def_chains_fn) (tree, tree, void *);
747 extern void init_tree_ssa (void);
748 extern edge ssa_redirect_edge (edge, basic_block);
749 extern void flush_pending_stmts (edge);
750 extern bool tree_ssa_useless_type_conversion (tree);
751 extern bool tree_ssa_useless_type_conversion_1 (tree, tree);
752 extern void verify_ssa (bool);
753 extern void delete_tree_ssa (void);
754 extern void walk_use_def_chains (tree, walk_use_def_chains_fn, void *, bool);
755 extern bool stmt_references_memory_p (tree);
757 /* In tree-into-ssa.c */
758 void update_ssa (unsigned);
759 void delete_update_ssa (void);
760 void register_new_name_mapping (tree, tree);
761 tree create_new_def_for (tree, tree, def_operand_p);
762 bool need_ssa_update_p (void);
763 bool name_mappings_registered_p (void);
764 bool name_registered_for_update_p (tree);
765 bitmap ssa_names_to_replace (void);
766 void release_ssa_name_after_update_ssa (tree);
767 void compute_global_livein (bitmap, bitmap);
768 tree duplicate_ssa_name (tree, tree);
769 void mark_sym_for_renaming (tree);
770 void mark_set_for_renaming (bitmap);
771 tree get_current_def (tree);
772 void set_current_def (tree, tree);
774 /* In tree-ssa-ccp.c */
775 bool fold_stmt (tree *);
776 bool fold_stmt_inplace (tree);
777 tree widen_bitfield (tree, tree, tree);
780 tree vrp_evaluate_conditional (tree, tree);
781 void simplify_stmt_using_ranges (tree);
783 /* In tree-ssa-dom.c */
784 extern void dump_dominator_optimization_stats (FILE *);
785 extern void debug_dominator_optimization_stats (void);
786 int loop_depth_of_name (tree);
788 /* In tree-ssa-copy.c */
789 extern void merge_alias_info (tree, tree);
790 extern void propagate_value (use_operand_p, tree);
791 extern void propagate_tree_value (tree *, tree);
792 extern void replace_exp (use_operand_p, tree);
793 extern bool may_propagate_copy (tree, tree);
794 extern bool may_propagate_copy_into_asm (tree);
800 /* Iv = BASE + STEP * i. */
803 /* True if this iv does not overflow. */
807 /* Description of number of iterations of a loop. All the expressions inside
808 the structure can be evaluated at the end of the loop's preheader
809 (and due to ssa form, also anywhere inside the body of the loop). */
811 struct tree_niter_desc
813 tree assumptions; /* The boolean expression. If this expression evaluates
814 to false, then the other fields in this structure
815 should not be used; there is no guarantee that they
817 tree may_be_zero; /* The boolean expression. If it evaluates to true,
818 the loop will exit in the first iteration (i.e.
819 its latch will not be executed), even if the niter
820 field says otherwise. */
821 tree niter; /* The expression giving the number of iterations of
822 a loop (provided that assumptions == true and
823 may_be_zero == false), more precisely the number
824 of executions of the latch of the loop. */
825 tree additional_info; /* The boolean expression. Sometimes we use additional
826 knowledge to simplify the other expressions
827 contained in this structure (for example the
828 knowledge about value ranges of operands on entry to
829 the loop). If this is a case, conjunction of such
830 condition is stored in this field, so that we do not
831 lose the information: for example if may_be_zero
832 is (n <= 0) and niter is (unsigned) n, we know
833 that the number of iterations is at most
834 MAX_SIGNED_INT. However if the (n <= 0) assumption
835 is eliminated (by looking at the guard on entry of
836 the loop), then the information would be lost. */
838 /* The simplified shape of the exit condition. The loop exits if
839 CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
840 LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
841 LE_EXPR and negative if CMP is GE_EXPR. This information is used
842 by loop unrolling. */
848 /* In tree-vectorizer.c */
849 unsigned vectorize_loops (void);
850 extern bool vect_can_force_dr_alignment_p (tree, unsigned int);
851 extern tree get_vectype_for_scalar_type (tree);
853 /* In tree-ssa-phiopt.c */
854 bool empty_block_p (basic_block);
856 /* In tree-ssa-loop*.c */
858 void tree_ssa_lim (void);
859 unsigned int tree_ssa_unswitch_loops (void);
860 unsigned int canonicalize_induction_variables (void);
861 unsigned int tree_unroll_loops_completely (bool);
862 unsigned int tree_ssa_prefetch_arrays (void);
863 unsigned int remove_empty_loops (void);
864 void tree_ssa_iv_optimize (void);
866 bool number_of_iterations_exit (struct loop *, edge,
867 struct tree_niter_desc *niter, bool);
868 tree find_loop_niter (struct loop *, edge *);
869 tree loop_niter_by_eval (struct loop *, edge);
870 tree find_loop_niter_by_eval (struct loop *, edge *);
871 void estimate_numbers_of_iterations (void);
872 bool scev_probably_wraps_p (tree, tree, tree, struct loop *, bool);
873 bool convert_affine_scev (struct loop *, tree, tree *, tree *, tree, bool);
875 bool nowrap_type_p (tree);
876 enum ev_direction {EV_DIR_GROWS, EV_DIR_DECREASES, EV_DIR_UNKNOWN};
877 enum ev_direction scev_direction (tree);
879 void free_numbers_of_iterations_estimates (void);
880 void free_numbers_of_iterations_estimates_loop (struct loop *);
881 void rewrite_into_loop_closed_ssa (bitmap, unsigned);
882 void verify_loop_closed_ssa (void);
883 bool for_each_index (tree *, bool (*) (tree, tree *, void *), void *);
884 void create_iv (tree, tree, tree, struct loop *, block_stmt_iterator *, bool,
886 void split_loop_exit_edge (edge);
887 unsigned force_expr_to_var_cost (tree);
888 void standard_iv_increment_position (struct loop *, block_stmt_iterator *,
890 basic_block ip_end_pos (struct loop *);
891 basic_block ip_normal_pos (struct loop *);
892 bool tree_duplicate_loop_to_header_edge (struct loop *, edge,
893 unsigned int, sbitmap,
894 edge, VEC (edge, heap) **,
896 struct loop *tree_ssa_loop_version (struct loop *, tree,
898 tree expand_simple_operations (tree);
899 void substitute_in_loop_info (struct loop *, tree, tree);
900 edge single_dom_exit (struct loop *);
901 bool can_unroll_loop_p (struct loop *loop, unsigned factor,
902 struct tree_niter_desc *niter);
903 void tree_unroll_loop (struct loop *, unsigned,
904 edge, struct tree_niter_desc *);
905 typedef void (*transform_callback)(struct loop *, void *);
906 void tree_transform_and_unroll_loop (struct loop *, unsigned,
907 edge, struct tree_niter_desc *,
908 transform_callback, void *);
909 bool contains_abnormal_ssa_name_p (tree);
911 /* In tree-ssa-threadedge.c */
912 extern bool potentially_threadable_block (basic_block);
913 extern void thread_across_edge (tree, edge, bool,
914 VEC(tree, heap) **, tree (*) (tree, tree));
916 /* In tree-ssa-loop-im.c */
917 /* The possibilities of statement movement. */
921 MOVE_IMPOSSIBLE, /* No movement -- side effect expression. */
922 MOVE_PRESERVE_EXECUTION, /* Must not cause the non-executed statement
923 become executed -- memory accesses, ... */
924 MOVE_POSSIBLE /* Unlimited movement. */
926 extern enum move_pos movement_possibility (tree);
928 /* The reasons a variable may escape a function. */
931 NO_ESCAPE = 0, /* Doesn't escape. */
932 ESCAPE_STORED_IN_GLOBAL = 1 << 1,
933 ESCAPE_TO_ASM = 1 << 2, /* Passed by address to an assembly
935 ESCAPE_TO_CALL = 1 << 3, /* Escapes to a function call. */
936 ESCAPE_BAD_CAST = 1 << 4, /* Cast from pointer to integer */
937 ESCAPE_TO_RETURN = 1 << 5, /* Returned from function. */
938 ESCAPE_TO_PURE_CONST = 1 << 6, /* Escapes to a pure or constant
940 ESCAPE_IS_GLOBAL = 1 << 7, /* Is a global variable. */
941 ESCAPE_IS_PARM = 1 << 8, /* Is an incoming function argument. */
942 ESCAPE_UNKNOWN = 1 << 9 /* We believe it escapes for
943 some reason not enumerated
947 /* In tree-flow-inline.h */
948 static inline bool is_call_clobbered (tree);
949 static inline void mark_call_clobbered (tree, unsigned int);
950 static inline void set_is_used (tree);
951 static inline bool unmodifiable_var_p (tree);
954 extern void make_eh_edges (tree);
955 extern bool tree_could_trap_p (tree);
956 extern bool tree_could_throw_p (tree);
957 extern bool tree_can_throw_internal (tree);
958 extern bool tree_can_throw_external (tree);
959 extern int lookup_stmt_eh_region (tree);
960 extern void add_stmt_to_eh_region (tree, int);
961 extern bool remove_stmt_from_eh_region (tree);
962 extern bool maybe_clean_or_replace_eh_stmt (tree, tree);
964 /* In tree-ssa-pre.c */
965 void add_to_value (tree, tree);
966 void debug_value_expressions (tree);
967 void print_value_expressions (FILE *, tree);
971 bool expressions_equal_p (tree, tree);
972 static inline tree get_value_handle (tree);
973 hashval_t vn_compute (tree, hashval_t);
974 void sort_vuses (VEC (tree, gc) *);
975 tree vn_lookup_or_add (tree, tree);
976 tree vn_lookup_or_add_with_vuses (tree, VEC (tree, gc) *);
977 void vn_add (tree, tree);
978 void vn_add_with_vuses (tree, tree, VEC (tree, gc) *);
979 tree vn_lookup (tree, tree);
980 tree vn_lookup_with_vuses (tree, VEC (tree, gc) *);
982 void vn_delete (void);
984 /* In tree-ssa-sink.c */
985 bool is_hidden_global_store (tree);
988 void insert_edge_copies (tree, basic_block);
989 void sra_insert_before (block_stmt_iterator *, tree);
990 void sra_insert_after (block_stmt_iterator *, tree);
991 void sra_init_cache (void);
992 bool sra_type_can_be_decomposed_p (tree);
994 /* In tree-loop-linear.c */
995 extern void linear_transform_loops (void);
997 /* In tree-data-ref.c */
998 extern void tree_check_data_deps (void);
1000 /* In tree-ssa-loop-ivopts.c */
1001 bool expr_invariant_in_loop_p (struct loop *, tree);
1002 bool multiplier_allowed_in_address_p (HOST_WIDE_INT, enum machine_mode);
1003 unsigned multiply_by_cost (HOST_WIDE_INT, enum machine_mode);
1005 /* In tree-ssa-threadupdate.c. */
1006 extern bool thread_through_all_blocks (void);
1007 extern void register_jump_thread (edge, edge);
1010 tree force_gimple_operand (tree, tree *, bool, tree);
1011 tree force_gimple_operand_bsi (block_stmt_iterator *, tree, bool, tree);
1013 /* In tree-ssa-structalias.c */
1014 bool find_what_p_points_to (tree);
1016 /* In tree-ssa-live.c */
1017 extern void remove_unused_locals (void);
1019 /* In tree-ssa-address.c */
1021 /* Description of a memory address. */
1025 tree symbol, base, index, step, offset;
1028 struct affine_tree_combination;
1029 tree create_mem_ref (block_stmt_iterator *, tree,
1030 struct affine_tree_combination *);
1031 rtx addr_for_mem_ref (struct mem_address *, bool);
1032 void get_address_description (tree, struct mem_address *);
1033 tree maybe_fold_tmr (tree);
1035 /* This structure is simply used during pushing fields onto the fieldstack
1036 to track the offset of the field, since bitpos_of_field gives it relative
1037 to its immediate containing type, and we want it relative to the ultimate
1038 containing object. */
1045 HOST_WIDE_INT offset;
1047 typedef struct fieldoff fieldoff_s;
1049 DEF_VEC_O(fieldoff_s);
1050 DEF_VEC_ALLOC_O(fieldoff_s,heap);
1051 int push_fields_onto_fieldstack (tree, VEC(fieldoff_s,heap) **,
1052 HOST_WIDE_INT, bool *);
1053 void sort_fieldstack (VEC(fieldoff_s,heap) *);
1055 void init_alias_heapvars (void);
1056 void delete_alias_heapvars (void);
1057 unsigned int execute_fixup_cfg (void);
1059 #include "tree-flow-inline.h"
1061 void swap_tree_operands (tree, tree *, tree *);
1063 int least_common_multiple (int, int);
1065 #endif /* _TREE_FLOW_H */