1 /* Define control flow data structures for the CFG.
2 Copyright (C) 1987, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
3 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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/>. */
21 #ifndef GCC_BASIC_BLOCK_H
22 #define GCC_BASIC_BLOCK_H
28 /* Type we use to hold basic block counters. Should be at least
29 64bit. Although a counter cannot be negative, we use a signed
30 type, because erroneous negative counts can be generated when the
31 flow graph is manipulated by various optimizations. A signed type
32 makes those easy to detect. */
33 typedef HOST_WIDEST_INT gcov_type
;
35 /* Control flow edge information. */
36 struct GTY(()) edge_def
{
37 /* The two blocks at the ends of the edge. */
38 struct basic_block_def
*src
;
39 struct basic_block_def
*dest
;
41 /* Instructions queued on the edge. */
42 union edge_def_insns
{
43 gimple_seq
GTY ((tag ("true"))) g
;
44 rtx
GTY ((tag ("false"))) r
;
45 } GTY ((desc ("current_ir_type () == IR_GIMPLE"))) insns
;
47 /* Auxiliary info specific to a pass. */
48 PTR
GTY ((skip (""))) aux
;
50 /* Location of any goto implicit in the edge and associated BLOCK. */
52 location_t goto_locus
;
54 /* The index number corresponding to this edge in the edge vector
56 unsigned int dest_idx
;
58 int flags
; /* see EDGE_* below */
59 int probability
; /* biased by REG_BR_PROB_BASE */
60 gcov_type count
; /* Expected number of executions calculated
65 DEF_VEC_ALLOC_P(edge
,gc
);
66 DEF_VEC_ALLOC_P(edge
,heap
);
68 #define EDGE_FALLTHRU 1 /* 'Straight line' flow */
69 #define EDGE_ABNORMAL 2 /* Strange flow, like computed
71 #define EDGE_ABNORMAL_CALL 4 /* Call with abnormal exit
72 like an exception, or sibcall */
73 #define EDGE_EH 8 /* Exception throw */
74 #define EDGE_FAKE 16 /* Not a real edge (profile.c) */
75 #define EDGE_DFS_BACK 32 /* A backwards edge */
76 #define EDGE_CAN_FALLTHRU 64 /* Candidate for straight line
78 #define EDGE_IRREDUCIBLE_LOOP 128 /* Part of irreducible loop. */
79 #define EDGE_SIBCALL 256 /* Edge from sibcall to exit. */
80 #define EDGE_LOOP_EXIT 512 /* Exit of a loop. */
81 #define EDGE_TRUE_VALUE 1024 /* Edge taken when controlling
82 predicate is nonzero. */
83 #define EDGE_FALSE_VALUE 2048 /* Edge taken when controlling
85 #define EDGE_EXECUTABLE 4096 /* Edge is executable. Only
86 valid during SSA-CCP. */
87 #define EDGE_CROSSING 8192 /* Edge crosses between hot
88 and cold sections, when we
90 #define EDGE_ALL_FLAGS 16383
92 #define EDGE_COMPLEX (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH)
94 /* Counter summary from the last set of coverage counts read by
96 extern const struct gcov_ctr_summary
*profile_info
;
98 /* Declared in cfgloop.h. */
101 /* Declared in tree-flow.h. */
104 /* A basic block is a sequence of instructions with only entry and
105 only one exit. If any one of the instructions are executed, they
106 will all be executed, and in sequence from first to last.
108 There may be COND_EXEC instructions in the basic block. The
109 COND_EXEC *instructions* will be executed -- but if the condition
110 is false the conditionally executed *expressions* will of course
111 not be executed. We don't consider the conditionally executed
112 expression (which might have side-effects) to be in a separate
113 basic block because the program counter will always be at the same
114 location after the COND_EXEC instruction, regardless of whether the
115 condition is true or not.
117 Basic blocks need not start with a label nor end with a jump insn.
118 For example, a previous basic block may just "conditionally fall"
119 into the succeeding basic block, and the last basic block need not
120 end with a jump insn. Block 0 is a descendant of the entry block.
122 A basic block beginning with two labels cannot have notes between
125 Data for jump tables are stored in jump_insns that occur in no
126 basic block even though these insns can follow or precede insns in
129 /* Basic block information indexed by block number. */
130 struct GTY((chain_next ("%h.next_bb"), chain_prev ("%h.prev_bb"))) basic_block_def
{
131 /* The edges into and out of the block. */
135 /* Auxiliary info specific to a pass. */
136 PTR
GTY ((skip (""))) aux
;
138 /* Innermost loop containing the block. */
139 struct loop
*loop_father
;
141 /* The dominance and postdominance information node. */
142 struct et_node
* GTY ((skip (""))) dom
[2];
144 /* Previous and next blocks in the chain. */
145 struct basic_block_def
*prev_bb
;
146 struct basic_block_def
*next_bb
;
148 union basic_block_il_dependent
{
149 struct gimple_bb_info
* GTY ((tag ("0"))) gimple
;
150 struct rtl_bb_info
* GTY ((tag ("1"))) rtl
;
151 } GTY ((desc ("((%1.flags & BB_RTL) != 0)"))) il
;
153 /* Expected number of executions: calculated in profile.c. */
156 /* The index of this block. */
159 /* The loop depth of this block. */
162 /* Expected frequency. Normalized to be in range 0 to BB_FREQ_MAX. */
165 /* Various flags. See BB_* below. */
169 struct GTY(()) rtl_bb_info
{
170 /* The first and last insns of the block. */
174 /* In CFGlayout mode points to insn notes/jumptables to be placed just before
175 and after the block. */
179 /* This field is used by the bb-reorder and tracer passes. */
183 struct GTY(()) gimple_bb_info
{
184 /* Sequence of statements in this block. */
187 /* PHI nodes for this block. */
188 gimple_seq phi_nodes
;
191 DEF_VEC_P(basic_block
);
192 DEF_VEC_ALLOC_P(basic_block
,gc
);
193 DEF_VEC_ALLOC_P(basic_block
,heap
);
195 #define BB_FREQ_MAX 10000
197 /* Masks for basic_block.flags.
199 BB_HOT_PARTITION and BB_COLD_PARTITION should be preserved throughout
200 the compilation, so they are never cleared.
202 All other flags may be cleared by clear_bb_flags(). It is generally
203 a bad idea to rely on any flags being up-to-date. */
207 /* Only set on blocks that have just been created by create_bb. */
210 /* Set by find_unreachable_blocks. Do not rely on this being set in any
212 BB_REACHABLE
= 1 << 1,
214 /* Set for blocks in an irreducible loop by loop analysis. */
215 BB_IRREDUCIBLE_LOOP
= 1 << 2,
217 /* Set on blocks that may actually not be single-entry single-exit block. */
218 BB_SUPERBLOCK
= 1 << 3,
220 /* Set on basic blocks that the scheduler should not touch. This is used
221 by SMS to prevent other schedulers from messing with the loop schedule. */
222 BB_DISABLE_SCHEDULE
= 1 << 4,
224 /* Set on blocks that should be put in a hot section. */
225 BB_HOT_PARTITION
= 1 << 5,
227 /* Set on blocks that should be put in a cold section. */
228 BB_COLD_PARTITION
= 1 << 6,
230 /* Set on block that was duplicated. */
231 BB_DUPLICATED
= 1 << 7,
233 /* Set if the label at the top of this block is the target of a non-local goto. */
234 BB_NON_LOCAL_GOTO_TARGET
= 1 << 8,
236 /* Set on blocks that are in RTL format. */
239 /* Set on blocks that are forwarder blocks.
240 Only used in cfgcleanup.c. */
241 BB_FORWARDER_BLOCK
= 1 << 10,
243 /* Set on blocks that cannot be threaded through.
244 Only used in cfgcleanup.c. */
245 BB_NONTHREADABLE_BLOCK
= 1 << 11,
247 /* Set on blocks that were modified in some way. This bit is set in
248 df_set_bb_dirty, but not cleared by df_analyze, so it can be used
249 to test whether a block has been modified prior to a df_analyze
251 BB_MODIFIED
= 1 << 12
254 /* Dummy flag for convenience in the hot/cold partitioning code. */
255 #define BB_UNPARTITIONED 0
257 /* Partitions, to be used when partitioning hot and cold basic blocks into
258 separate sections. */
259 #define BB_PARTITION(bb) ((bb)->flags & (BB_HOT_PARTITION|BB_COLD_PARTITION))
260 #define BB_SET_PARTITION(bb, part) do { \
261 basic_block bb_ = (bb); \
262 bb_->flags = ((bb_->flags & ~(BB_HOT_PARTITION|BB_COLD_PARTITION)) \
266 #define BB_COPY_PARTITION(dstbb, srcbb) \
267 BB_SET_PARTITION (dstbb, BB_PARTITION (srcbb))
269 /* State of dominance information. */
273 DOM_NONE
, /* Not computed at all. */
274 DOM_NO_FAST_QUERY
, /* The data is OK, but the fast query data are not usable. */
275 DOM_OK
/* Everything is ok. */
278 /* What sort of profiling information we have. */
279 enum profile_status_d
286 /* A structure to group all the per-function control flow graph data.
287 The x_* prefixing is necessary because otherwise references to the
288 fields of this struct are interpreted as the defines for backward
289 source compatibility following the definition of this struct. */
290 struct GTY(()) control_flow_graph
{
291 /* Block pointers for the exit and entry of a function.
292 These are always the head and tail of the basic block list. */
293 basic_block x_entry_block_ptr
;
294 basic_block x_exit_block_ptr
;
296 /* Index by basic block number, get basic block struct info. */
297 VEC(basic_block
,gc
) *x_basic_block_info
;
299 /* Number of basic blocks in this flow graph. */
300 int x_n_basic_blocks
;
302 /* Number of edges in this flow graph. */
305 /* The first free basic block number. */
306 int x_last_basic_block
;
308 /* UIDs for LABEL_DECLs. */
311 /* Mapping of labels to their associated blocks. At present
312 only used for the gimple CFG. */
313 VEC(basic_block
,gc
) *x_label_to_block_map
;
315 enum profile_status_d x_profile_status
;
317 /* Whether the dominators and the postdominators are available. */
318 enum dom_state x_dom_computed
[2];
320 /* Number of basic blocks in the dominance tree. */
321 unsigned x_n_bbs_in_dom_tree
[2];
323 /* Maximal number of entities in the single jumptable. Used to estimate
324 final flowgraph size. */
325 int max_jumptable_ents
;
328 /* Defines for accessing the fields of the CFG structure for function FN. */
329 #define ENTRY_BLOCK_PTR_FOR_FUNCTION(FN) ((FN)->cfg->x_entry_block_ptr)
330 #define EXIT_BLOCK_PTR_FOR_FUNCTION(FN) ((FN)->cfg->x_exit_block_ptr)
331 #define basic_block_info_for_function(FN) ((FN)->cfg->x_basic_block_info)
332 #define n_basic_blocks_for_function(FN) ((FN)->cfg->x_n_basic_blocks)
333 #define n_edges_for_function(FN) ((FN)->cfg->x_n_edges)
334 #define last_basic_block_for_function(FN) ((FN)->cfg->x_last_basic_block)
335 #define label_to_block_map_for_function(FN) ((FN)->cfg->x_label_to_block_map)
336 #define profile_status_for_function(FN) ((FN)->cfg->x_profile_status)
338 #define BASIC_BLOCK_FOR_FUNCTION(FN,N) \
339 (VEC_index (basic_block, basic_block_info_for_function(FN), (N)))
340 #define SET_BASIC_BLOCK_FOR_FUNCTION(FN,N,BB) \
341 (VEC_replace (basic_block, basic_block_info_for_function(FN), (N), (BB)))
343 /* Defines for textual backward source compatibility. */
344 #define ENTRY_BLOCK_PTR (cfun->cfg->x_entry_block_ptr)
345 #define EXIT_BLOCK_PTR (cfun->cfg->x_exit_block_ptr)
346 #define basic_block_info (cfun->cfg->x_basic_block_info)
347 #define n_basic_blocks (cfun->cfg->x_n_basic_blocks)
348 #define n_edges (cfun->cfg->x_n_edges)
349 #define last_basic_block (cfun->cfg->x_last_basic_block)
350 #define label_to_block_map (cfun->cfg->x_label_to_block_map)
351 #define profile_status (cfun->cfg->x_profile_status)
353 #define BASIC_BLOCK(N) (VEC_index (basic_block, basic_block_info, (N)))
354 #define SET_BASIC_BLOCK(N,BB) (VEC_replace (basic_block, basic_block_info, (N), (BB)))
356 /* For iterating over basic blocks. */
357 #define FOR_BB_BETWEEN(BB, FROM, TO, DIR) \
358 for (BB = FROM; BB != TO; BB = BB->DIR)
360 #define FOR_EACH_BB_FN(BB, FN) \
361 FOR_BB_BETWEEN (BB, (FN)->cfg->x_entry_block_ptr->next_bb, (FN)->cfg->x_exit_block_ptr, next_bb)
363 #define FOR_EACH_BB(BB) FOR_EACH_BB_FN (BB, cfun)
365 #define FOR_EACH_BB_REVERSE_FN(BB, FN) \
366 FOR_BB_BETWEEN (BB, (FN)->cfg->x_exit_block_ptr->prev_bb, (FN)->cfg->x_entry_block_ptr, prev_bb)
368 #define FOR_EACH_BB_REVERSE(BB) FOR_EACH_BB_REVERSE_FN(BB, cfun)
370 /* For iterating over insns in basic block. */
371 #define FOR_BB_INSNS(BB, INSN) \
372 for ((INSN) = BB_HEAD (BB); \
373 (INSN) && (INSN) != NEXT_INSN (BB_END (BB)); \
374 (INSN) = NEXT_INSN (INSN))
376 /* For iterating over insns in basic block when we might remove the
378 #define FOR_BB_INSNS_SAFE(BB, INSN, CURR) \
379 for ((INSN) = BB_HEAD (BB), (CURR) = (INSN) ? NEXT_INSN ((INSN)): NULL; \
380 (INSN) && (INSN) != NEXT_INSN (BB_END (BB)); \
381 (INSN) = (CURR), (CURR) = (INSN) ? NEXT_INSN ((INSN)) : NULL)
383 #define FOR_BB_INSNS_REVERSE(BB, INSN) \
384 for ((INSN) = BB_END (BB); \
385 (INSN) && (INSN) != PREV_INSN (BB_HEAD (BB)); \
386 (INSN) = PREV_INSN (INSN))
388 #define FOR_BB_INSNS_REVERSE_SAFE(BB, INSN, CURR) \
389 for ((INSN) = BB_END (BB),(CURR) = (INSN) ? PREV_INSN ((INSN)) : NULL; \
390 (INSN) && (INSN) != PREV_INSN (BB_HEAD (BB)); \
391 (INSN) = (CURR), (CURR) = (INSN) ? PREV_INSN ((INSN)) : NULL)
393 /* Cycles through _all_ basic blocks, even the fake ones (entry and
396 #define FOR_ALL_BB(BB) \
397 for (BB = ENTRY_BLOCK_PTR; BB; BB = BB->next_bb)
399 #define FOR_ALL_BB_FN(BB, FN) \
400 for (BB = ENTRY_BLOCK_PTR_FOR_FUNCTION (FN); BB; BB = BB->next_bb)
403 /* Stuff for recording basic block info. */
405 #define BB_HEAD(B) (B)->il.rtl->head_
406 #define BB_END(B) (B)->il.rtl->end_
408 /* Special block numbers [markers] for entry and exit.
409 Neither of them is supposed to hold actual statements. */
410 #define ENTRY_BLOCK (0)
411 #define EXIT_BLOCK (1)
413 /* The two blocks that are always in the cfg. */
414 #define NUM_FIXED_BLOCKS (2)
416 #define set_block_for_insn(INSN, BB) (BLOCK_FOR_INSN (INSN) = BB)
418 extern void compute_bb_for_insn (void);
419 extern unsigned int free_bb_for_insn (void);
420 extern void update_bb_for_insn (basic_block
);
422 extern void insert_insn_on_edge (rtx
, edge
);
423 basic_block
split_edge_and_insert (edge
, rtx
);
425 extern void commit_one_edge_insertion (edge e
);
426 extern void commit_edge_insertions (void);
428 extern void remove_fake_edges (void);
429 extern void remove_fake_exit_edges (void);
430 extern void add_noreturn_fake_exit_edges (void);
431 extern void connect_infinite_loops_to_exit (void);
432 extern edge
unchecked_make_edge (basic_block
, basic_block
, int);
433 extern edge
cached_make_edge (sbitmap
, basic_block
, basic_block
, int);
434 extern edge
make_edge (basic_block
, basic_block
, int);
435 extern edge
make_single_succ_edge (basic_block
, basic_block
, int);
436 extern void remove_edge_raw (edge
);
437 extern void redirect_edge_succ (edge
, basic_block
);
438 extern edge
redirect_edge_succ_nodup (edge
, basic_block
);
439 extern void redirect_edge_pred (edge
, basic_block
);
440 extern basic_block
create_basic_block_structure (rtx
, rtx
, rtx
, basic_block
);
441 extern void clear_bb_flags (void);
442 extern int post_order_compute (int *, bool, bool);
443 extern int inverted_post_order_compute (int *);
444 extern int pre_and_rev_post_order_compute (int *, int *, bool);
445 extern int dfs_enumerate_from (basic_block
, int,
446 bool (*)(const_basic_block
, const void *),
447 basic_block
*, int, const void *);
448 extern void compute_dominance_frontiers (struct bitmap_head_def
*);
449 extern bitmap
compute_idf (bitmap
, struct bitmap_head_def
*);
450 extern void dump_bb_info (basic_block
, bool, bool, int, const char *, FILE *);
451 extern void dump_edge_info (FILE *, edge
, int);
452 extern void brief_dump_cfg (FILE *);
453 extern void clear_edges (void);
454 extern void scale_bbs_frequencies_int (basic_block
*, int, int, int);
455 extern void scale_bbs_frequencies_gcov_type (basic_block
*, int, gcov_type
,
458 /* Structure to group all of the information to process IF-THEN and
459 IF-THEN-ELSE blocks for the conditional execution support. This
460 needs to be in a public file in case the IFCVT macros call
461 functions passing the ce_if_block data structure. */
463 typedef struct ce_if_block
465 basic_block test_bb
; /* First test block. */
466 basic_block then_bb
; /* THEN block. */
467 basic_block else_bb
; /* ELSE block or NULL. */
468 basic_block join_bb
; /* Join THEN/ELSE blocks. */
469 basic_block last_test_bb
; /* Last bb to hold && or || tests. */
470 int num_multiple_test_blocks
; /* # of && and || basic blocks. */
471 int num_and_and_blocks
; /* # of && blocks. */
472 int num_or_or_blocks
; /* # of || blocks. */
473 int num_multiple_test_insns
; /* # of insns in && and || blocks. */
474 int and_and_p
; /* Complex test is &&. */
475 int num_then_insns
; /* # of insns in THEN block. */
476 int num_else_insns
; /* # of insns in ELSE block. */
477 int pass
; /* Pass number. */
479 #ifdef IFCVT_EXTRA_FIELDS
480 IFCVT_EXTRA_FIELDS
/* Any machine dependent fields. */
485 /* This structure maintains an edge list vector. */
493 /* The base value for branch probability notes and edge probabilities. */
494 #define REG_BR_PROB_BASE 10000
496 /* This is the value which indicates no edge is present. */
497 #define EDGE_INDEX_NO_EDGE -1
499 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
500 if there is no edge between the 2 basic blocks. */
501 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
503 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
504 block which is either the pred or succ end of the indexed edge. */
505 #define INDEX_EDGE_PRED_BB(el, index) ((el)->index_to_edge[(index)]->src)
506 #define INDEX_EDGE_SUCC_BB(el, index) ((el)->index_to_edge[(index)]->dest)
508 /* INDEX_EDGE returns a pointer to the edge. */
509 #define INDEX_EDGE(el, index) ((el)->index_to_edge[(index)])
511 /* Number of edges in the compressed edge list. */
512 #define NUM_EDGES(el) ((el)->num_edges)
514 /* BB is assumed to contain conditional jump. Return the fallthru edge. */
515 #define FALLTHRU_EDGE(bb) (EDGE_SUCC ((bb), 0)->flags & EDGE_FALLTHRU \
516 ? EDGE_SUCC ((bb), 0) : EDGE_SUCC ((bb), 1))
518 /* BB is assumed to contain conditional jump. Return the branch edge. */
519 #define BRANCH_EDGE(bb) (EDGE_SUCC ((bb), 0)->flags & EDGE_FALLTHRU \
520 ? EDGE_SUCC ((bb), 1) : EDGE_SUCC ((bb), 0))
522 /* Return expected execution frequency of the edge E. */
523 #define EDGE_FREQUENCY(e) (((e)->src->frequency \
525 + REG_BR_PROB_BASE / 2) \
528 /* Return nonzero if edge is critical. */
529 #define EDGE_CRITICAL_P(e) (EDGE_COUNT ((e)->src->succs) >= 2 \
530 && EDGE_COUNT ((e)->dest->preds) >= 2)
532 #define EDGE_COUNT(ev) VEC_length (edge, (ev))
533 #define EDGE_I(ev,i) VEC_index (edge, (ev), (i))
534 #define EDGE_PRED(bb,i) VEC_index (edge, (bb)->preds, (i))
535 #define EDGE_SUCC(bb,i) VEC_index (edge, (bb)->succs, (i))
537 /* Returns true if BB has precisely one successor. */
540 single_succ_p (const_basic_block bb
)
542 return EDGE_COUNT (bb
->succs
) == 1;
545 /* Returns true if BB has precisely one predecessor. */
548 single_pred_p (const_basic_block bb
)
550 return EDGE_COUNT (bb
->preds
) == 1;
553 /* Returns the single successor edge of basic block BB. Aborts if
554 BB does not have exactly one successor. */
557 single_succ_edge (const_basic_block bb
)
559 gcc_checking_assert (single_succ_p (bb
));
560 return EDGE_SUCC (bb
, 0);
563 /* Returns the single predecessor edge of basic block BB. Aborts
564 if BB does not have exactly one predecessor. */
567 single_pred_edge (const_basic_block bb
)
569 gcc_checking_assert (single_pred_p (bb
));
570 return EDGE_PRED (bb
, 0);
573 /* Returns the single successor block of basic block BB. Aborts
574 if BB does not have exactly one successor. */
576 static inline basic_block
577 single_succ (const_basic_block bb
)
579 return single_succ_edge (bb
)->dest
;
582 /* Returns the single predecessor block of basic block BB. Aborts
583 if BB does not have exactly one predecessor.*/
585 static inline basic_block
586 single_pred (const_basic_block bb
)
588 return single_pred_edge (bb
)->src
;
591 /* Iterator object for edges. */
595 VEC(edge
,gc
) **container
;
598 static inline VEC(edge
,gc
) *
599 ei_container (edge_iterator i
)
601 gcc_checking_assert (i
.container
);
605 #define ei_start(iter) ei_start_1 (&(iter))
606 #define ei_last(iter) ei_last_1 (&(iter))
608 /* Return an iterator pointing to the start of an edge vector. */
609 static inline edge_iterator
610 ei_start_1 (VEC(edge
,gc
) **ev
)
620 /* Return an iterator pointing to the last element of an edge
622 static inline edge_iterator
623 ei_last_1 (VEC(edge
,gc
) **ev
)
627 i
.index
= EDGE_COUNT (*ev
) - 1;
633 /* Is the iterator `i' at the end of the sequence? */
635 ei_end_p (edge_iterator i
)
637 return (i
.index
== EDGE_COUNT (ei_container (i
)));
640 /* Is the iterator `i' at one position before the end of the
643 ei_one_before_end_p (edge_iterator i
)
645 return (i
.index
+ 1 == EDGE_COUNT (ei_container (i
)));
648 /* Advance the iterator to the next element. */
650 ei_next (edge_iterator
*i
)
652 gcc_checking_assert (i
->index
< EDGE_COUNT (ei_container (*i
)));
656 /* Move the iterator to the previous element. */
658 ei_prev (edge_iterator
*i
)
660 gcc_checking_assert (i
->index
> 0);
664 /* Return the edge pointed to by the iterator `i'. */
666 ei_edge (edge_iterator i
)
668 return EDGE_I (ei_container (i
), i
.index
);
671 /* Return an edge pointed to by the iterator. Do it safely so that
672 NULL is returned when the iterator is pointing at the end of the
675 ei_safe_edge (edge_iterator i
)
677 return !ei_end_p (i
) ? ei_edge (i
) : NULL
;
680 /* Return 1 if we should continue to iterate. Return 0 otherwise.
681 *Edge P is set to the next edge if we are to continue to iterate
682 and NULL otherwise. */
685 ei_cond (edge_iterator ei
, edge
*p
)
699 /* This macro serves as a convenient way to iterate each edge in a
700 vector of predecessor or successor edges. It must not be used when
701 an element might be removed during the traversal, otherwise
702 elements will be missed. Instead, use a for-loop like that shown
703 in the following pseudo-code:
705 FOR (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
714 #define FOR_EACH_EDGE(EDGE,ITER,EDGE_VEC) \
715 for ((ITER) = ei_start ((EDGE_VEC)); \
716 ei_cond ((ITER), &(EDGE)); \
719 struct edge_list
* create_edge_list (void);
720 void free_edge_list (struct edge_list
*);
721 void print_edge_list (FILE *, struct edge_list
*);
722 void verify_edge_list (FILE *, struct edge_list
*);
723 int find_edge_index (struct edge_list
*, basic_block
, basic_block
);
724 edge
find_edge (basic_block
, basic_block
);
726 #define CLEANUP_EXPENSIVE 1 /* Do relatively expensive optimizations
727 except for edge forwarding */
728 #define CLEANUP_CROSSJUMP 2 /* Do crossjumping. */
729 #define CLEANUP_POST_REGSTACK 4 /* We run after reg-stack and need
730 to care REG_DEAD notes. */
731 #define CLEANUP_THREADING 8 /* Do jump threading. */
732 #define CLEANUP_NO_INSN_DEL 16 /* Do not try to delete trivially dead
734 #define CLEANUP_CFGLAYOUT 32 /* Do cleanup in cfglayout mode. */
737 extern struct edge_list
*pre_edge_lcm (int, sbitmap
*, sbitmap
*,
738 sbitmap
*, sbitmap
*, sbitmap
**,
740 extern struct edge_list
*pre_edge_rev_lcm (int, sbitmap
*,
741 sbitmap
*, sbitmap
*,
742 sbitmap
*, sbitmap
**,
744 extern void compute_available (sbitmap
*, sbitmap
*, sbitmap
*, sbitmap
*);
747 extern bool maybe_hot_count_p (gcov_type
);
748 extern bool maybe_hot_bb_p (const_basic_block
);
749 extern bool maybe_hot_edge_p (edge
);
750 extern bool probably_never_executed_bb_p (const_basic_block
);
751 extern bool optimize_bb_for_size_p (const_basic_block
);
752 extern bool optimize_bb_for_speed_p (const_basic_block
);
753 extern bool optimize_edge_for_size_p (edge
);
754 extern bool optimize_edge_for_speed_p (edge
);
755 extern bool optimize_loop_for_size_p (struct loop
*);
756 extern bool optimize_loop_for_speed_p (struct loop
*);
757 extern bool optimize_loop_nest_for_size_p (struct loop
*);
758 extern bool optimize_loop_nest_for_speed_p (struct loop
*);
759 extern bool gimple_predicted_by_p (const_basic_block
, enum br_predictor
);
760 extern bool rtl_predicted_by_p (const_basic_block
, enum br_predictor
);
761 extern void gimple_predict_edge (edge
, enum br_predictor
, int);
762 extern void rtl_predict_edge (edge
, enum br_predictor
, int);
763 extern void predict_edge_def (edge
, enum br_predictor
, enum prediction
);
764 extern void guess_outgoing_edge_probabilities (basic_block
);
765 extern void remove_predictions_associated_with_edge (edge
);
766 extern bool edge_probability_reliable_p (const_edge
);
767 extern bool br_prob_note_reliable_p (const_rtx
);
768 extern bool predictable_edge_p (edge
);
771 extern void init_flow (struct function
*);
772 extern void debug_bb (basic_block
);
773 extern basic_block
debug_bb_n (int);
774 extern void expunge_block (basic_block
);
775 extern void link_block (basic_block
, basic_block
);
776 extern void unlink_block (basic_block
);
777 extern void compact_blocks (void);
778 extern basic_block
alloc_block (void);
779 extern void alloc_aux_for_blocks (int);
780 extern void clear_aux_for_blocks (void);
781 extern void free_aux_for_blocks (void);
782 extern void alloc_aux_for_edges (int);
783 extern void clear_aux_for_edges (void);
784 extern void free_aux_for_edges (void);
787 extern void find_unreachable_blocks (void);
788 extern bool forwarder_block_p (const_basic_block
);
789 extern bool can_fallthru (basic_block
, basic_block
);
790 extern bool could_fall_through (basic_block
, basic_block
);
791 extern void flow_nodes_print (const char *, const_sbitmap
, FILE *);
792 extern void flow_edge_list_print (const char *, const edge
*, int, FILE *);
795 extern basic_block
force_nonfallthru (edge
);
796 extern rtx
block_label (basic_block
);
797 extern bool purge_all_dead_edges (void);
798 extern bool purge_dead_edges (basic_block
);
801 extern void find_many_sub_basic_blocks (sbitmap
);
802 extern void rtl_make_eh_edge (sbitmap
, basic_block
, rtx
);
804 /* In cfgcleanup.c. */
805 extern bool cleanup_cfg (int);
806 extern int flow_find_cross_jump (basic_block
, basic_block
, rtx
*, rtx
*);
807 extern int flow_find_head_matching_sequence (basic_block
, basic_block
,
810 extern bool delete_unreachable_blocks (void);
812 extern bool mark_dfs_back_edges (void);
813 extern void set_edge_can_fallthru_flag (void);
814 extern void update_br_prob_note (basic_block
);
815 extern void fixup_abnormal_edges (void);
816 extern bool inside_basic_block_p (const_rtx
);
817 extern bool control_flow_insn_p (const_rtx
);
818 extern rtx
get_last_bb_insn (basic_block
);
820 /* In bb-reorder.c */
821 extern void reorder_basic_blocks (void);
828 CDI_POST_DOMINATORS
= 2
831 extern enum dom_state
dom_info_state (enum cdi_direction
);
832 extern void set_dom_info_availability (enum cdi_direction
, enum dom_state
);
833 extern bool dom_info_available_p (enum cdi_direction
);
834 extern void calculate_dominance_info (enum cdi_direction
);
835 extern void free_dominance_info (enum cdi_direction
);
836 extern basic_block
nearest_common_dominator (enum cdi_direction
,
837 basic_block
, basic_block
);
838 extern basic_block
nearest_common_dominator_for_set (enum cdi_direction
,
840 extern void set_immediate_dominator (enum cdi_direction
, basic_block
,
842 extern basic_block
get_immediate_dominator (enum cdi_direction
, basic_block
);
843 extern bool dominated_by_p (enum cdi_direction
, const_basic_block
, const_basic_block
);
844 extern VEC (basic_block
, heap
) *get_dominated_by (enum cdi_direction
, basic_block
);
845 extern VEC (basic_block
, heap
) *get_dominated_by_region (enum cdi_direction
,
848 extern VEC (basic_block
, heap
) *get_dominated_to_depth (enum cdi_direction
,
850 extern VEC (basic_block
, heap
) *get_all_dominated_blocks (enum cdi_direction
,
852 extern void add_to_dominance_info (enum cdi_direction
, basic_block
);
853 extern void delete_from_dominance_info (enum cdi_direction
, basic_block
);
854 basic_block
recompute_dominator (enum cdi_direction
, basic_block
);
855 extern void redirect_immediate_dominators (enum cdi_direction
, basic_block
,
857 extern void iterate_fix_dominators (enum cdi_direction
,
858 VEC (basic_block
, heap
) *, bool);
859 extern void verify_dominators (enum cdi_direction
);
860 extern basic_block
first_dom_son (enum cdi_direction
, basic_block
);
861 extern basic_block
next_dom_son (enum cdi_direction
, basic_block
);
862 unsigned bb_dom_dfs_in (enum cdi_direction
, basic_block
);
863 unsigned bb_dom_dfs_out (enum cdi_direction
, basic_block
);
865 extern edge
try_redirect_by_replacing_jump (edge
, basic_block
, bool);
866 extern void break_superblocks (void);
867 extern void relink_block_chain (bool);
868 extern void check_bb_profile (basic_block
, FILE *);
869 extern void update_bb_profile_for_threading (basic_block
, int, gcov_type
, edge
);
870 extern void init_rtl_bb_info (basic_block
);
872 extern void initialize_original_copy_tables (void);
873 extern void free_original_copy_tables (void);
874 extern void set_bb_original (basic_block
, basic_block
);
875 extern basic_block
get_bb_original (basic_block
);
876 extern void set_bb_copy (basic_block
, basic_block
);
877 extern basic_block
get_bb_copy (basic_block
);
878 void set_loop_copy (struct loop
*, struct loop
*);
879 struct loop
*get_loop_copy (struct loop
*);
881 #include "cfghooks.h"
883 /* Return true when one of the predecessor edges of BB is marked with EDGE_EH. */
885 bb_has_eh_pred (basic_block bb
)
890 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
892 if (e
->flags
& EDGE_EH
)
898 /* Return true when one of the predecessor edges of BB is marked with EDGE_ABNORMAL. */
900 bb_has_abnormal_pred (basic_block bb
)
905 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
907 if (e
->flags
& EDGE_ABNORMAL
)
913 /* Return the fallthru edge in EDGES if it exists, NULL otherwise. */
915 find_fallthru_edge (VEC(edge
,gc
) *edges
)
920 FOR_EACH_EDGE (e
, ei
, edges
)
921 if (e
->flags
& EDGE_FALLTHRU
)
927 /* In cfgloopmanip.c. */
928 extern edge mfb_kj_edge
;
929 extern bool mfb_keep_just (edge
);
931 /* In cfgexpand.c. */
932 extern void rtl_profile_for_bb (basic_block
);
933 extern void rtl_profile_for_edge (edge
);
934 extern void default_rtl_profile (void);
936 #endif /* GCC_BASIC_BLOCK_H */