1 /* Define control flow data structures for the CFG.
2 Copyright (C) 1987-2013 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
20 #ifndef GCC_BASIC_BLOCK_H
21 #define GCC_BASIC_BLOCK_H
27 /* Use gcov_type to hold basic block counters. Should be at least
28 64bit. Although a counter cannot be negative, we use a signed
29 type, because erroneous negative counts can be generated when the
30 flow graph is manipulated by various optimizations. A signed type
31 makes those easy to detect. */
33 /* Control flow edge information. */
34 struct GTY((user
)) edge_def
{
35 /* The two blocks at the ends of the edge. */
39 /* Instructions queued on the edge. */
40 union edge_def_insns
{
45 /* Auxiliary info specific to a pass. */
48 /* Location of any goto implicit in the edge. */
49 location_t goto_locus
;
51 /* The index number corresponding to this edge in the edge vector
53 unsigned int dest_idx
;
55 int flags
; /* see cfg-flags.def */
56 int probability
; /* biased by REG_BR_PROB_BASE */
57 gcov_type count
; /* Expected number of executions calculated
62 /* Garbage collection and PCH support for edge_def. */
63 extern void gt_ggc_mx (edge_def
*e
);
64 extern void gt_pch_nx (edge_def
*e
);
65 extern void gt_pch_nx (edge_def
*e
, gt_pointer_operator
, void *);
67 /* Masks for edge.flags. */
68 #define DEF_EDGE_FLAG(NAME,IDX) EDGE_##NAME = 1 << IDX ,
70 #include "cfg-flags.def"
71 LAST_CFG_EDGE_FLAG
/* this is only used for EDGE_ALL_FLAGS */
75 /* Bit mask for all edge flags. */
76 #define EDGE_ALL_FLAGS ((LAST_CFG_EDGE_FLAG - 1) * 2 - 1)
78 /* The following four flags all indicate something special about an edge.
79 Test the edge flags on EDGE_COMPLEX to detect all forms of "strange"
80 control flow transfers. */
81 #define EDGE_COMPLEX \
82 (EDGE_ABNORMAL | EDGE_ABNORMAL_CALL | EDGE_EH | EDGE_PRESERVE)
84 /* Counter summary from the last set of coverage counts read by
86 extern const struct gcov_ctr_summary
*profile_info
;
88 /* Structure to gather statistic about profile consistency, per pass.
89 An array of this structure, indexed by pass static number, is allocated
90 in passes.c. The structure is defined here so that different CFG modes
91 can do their book-keeping via CFG hooks.
93 For every field[2], field[0] is the count before the pass runs, and
94 field[1] is the post-pass count. This allows us to monitor the effect
95 of each individual pass on the profile consistency.
97 This structure is not supposed to be used by anything other than passes.c
98 and one CFG hook per CFG mode. */
101 /* The number of basic blocks where sum(freq) of the block's predecessors
102 doesn't match reasonably well with the incoming frequency. */
103 int num_mismatched_freq_in
[2];
104 /* Likewise for a basic block's successors. */
105 int num_mismatched_freq_out
[2];
106 /* The number of basic blocks where sum(count) of the block's predecessors
107 doesn't match reasonably well with the incoming frequency. */
108 int num_mismatched_count_in
[2];
109 /* Likewise for a basic block's successors. */
110 int num_mismatched_count_out
[2];
111 /* A weighted cost of the run-time of the function body. */
113 /* A weighted cost of the size of the function body. */
115 /* True iff this pass actually was run. */
119 /* Declared in cfgloop.h. */
122 struct GTY(()) rtl_bb_info
{
123 /* The first insn of the block is embedded into bb->il.x. */
124 /* The last insn of the block. */
127 /* In CFGlayout mode points to insn notes/jumptables to be placed just before
128 and after the block. */
133 struct GTY(()) gimple_bb_info
{
134 /* Sequence of statements in this block. */
137 /* PHI nodes for this block. */
138 gimple_seq phi_nodes
;
141 /* A basic block is a sequence of instructions with only one entry and
142 only one exit. If any one of the instructions are executed, they
143 will all be executed, and in sequence from first to last.
145 There may be COND_EXEC instructions in the basic block. The
146 COND_EXEC *instructions* will be executed -- but if the condition
147 is false the conditionally executed *expressions* will of course
148 not be executed. We don't consider the conditionally executed
149 expression (which might have side-effects) to be in a separate
150 basic block because the program counter will always be at the same
151 location after the COND_EXEC instruction, regardless of whether the
152 condition is true or not.
154 Basic blocks need not start with a label nor end with a jump insn.
155 For example, a previous basic block may just "conditionally fall"
156 into the succeeding basic block, and the last basic block need not
157 end with a jump insn. Block 0 is a descendant of the entry block.
159 A basic block beginning with two labels cannot have notes between
162 Data for jump tables are stored in jump_insns that occur in no
163 basic block even though these insns can follow or precede insns in
166 /* Basic block information indexed by block number. */
167 struct GTY((chain_next ("%h.next_bb"), chain_prev ("%h.prev_bb"))) basic_block_def
{
168 /* The edges into and out of the block. */
169 vec
<edge
, va_gc
> *preds
;
170 vec
<edge
, va_gc
> *succs
;
172 /* Auxiliary info specific to a pass. */
173 PTR
GTY ((skip (""))) aux
;
175 /* Innermost loop containing the block. */
176 struct loop
*loop_father
;
178 /* The dominance and postdominance information node. */
179 struct et_node
* GTY ((skip (""))) dom
[2];
181 /* Previous and next blocks in the chain. */
185 union basic_block_il_dependent
{
186 struct gimple_bb_info
GTY ((tag ("0"))) gimple
;
189 struct rtl_bb_info
* rtl
;
190 } GTY ((tag ("1"))) x
;
191 } GTY ((desc ("((%1.flags & BB_RTL) != 0)"))) il
;
193 /* Various flags. See cfg-flags.def. */
196 /* The index of this block. */
199 /* Expected number of executions: calculated in profile.c. */
202 /* Expected frequency. Normalized to be in range 0 to BB_FREQ_MAX. */
205 /* The discriminator for this block. The discriminator distinguishes
206 among several basic blocks that share a common locus, allowing for
207 more accurate sample-based profiling. */
211 /* This ensures that struct gimple_bb_info is smaller than
212 struct rtl_bb_info, so that inlining the former into basic_block_def
213 is the better choice. */
214 typedef int __assert_gimple_bb_smaller_rtl_bb
215 [(int) sizeof (struct rtl_bb_info
)
216 - (int) sizeof (struct gimple_bb_info
)];
219 #define BB_FREQ_MAX 10000
221 /* Masks for basic_block.flags. */
222 #define DEF_BASIC_BLOCK_FLAG(NAME,IDX) BB_##NAME = 1 << IDX ,
225 #include "cfg-flags.def"
226 LAST_CFG_BB_FLAG
/* this is only used for BB_ALL_FLAGS */
228 #undef DEF_BASIC_BLOCK_FLAG
230 /* Bit mask for all basic block flags. */
231 #define BB_ALL_FLAGS ((LAST_CFG_BB_FLAG - 1) * 2 - 1)
233 /* Bit mask for all basic block flags that must be preserved. These are
234 the bit masks that are *not* cleared by clear_bb_flags. */
235 #define BB_FLAGS_TO_PRESERVE \
236 (BB_DISABLE_SCHEDULE | BB_RTL | BB_NON_LOCAL_GOTO_TARGET \
237 | BB_HOT_PARTITION | BB_COLD_PARTITION)
239 /* Dummy bitmask for convenience in the hot/cold partitioning code. */
240 #define BB_UNPARTITIONED 0
242 /* Partitions, to be used when partitioning hot and cold basic blocks into
243 separate sections. */
244 #define BB_PARTITION(bb) ((bb)->flags & (BB_HOT_PARTITION|BB_COLD_PARTITION))
245 #define BB_SET_PARTITION(bb, part) do { \
246 basic_block bb_ = (bb); \
247 bb_->flags = ((bb_->flags & ~(BB_HOT_PARTITION|BB_COLD_PARTITION)) \
251 #define BB_COPY_PARTITION(dstbb, srcbb) \
252 BB_SET_PARTITION (dstbb, BB_PARTITION (srcbb))
254 /* State of dominance information. */
258 DOM_NONE
, /* Not computed at all. */
259 DOM_NO_FAST_QUERY
, /* The data is OK, but the fast query data are not usable. */
260 DOM_OK
/* Everything is ok. */
263 /* What sort of profiling information we have. */
264 enum profile_status_d
269 PROFILE_LAST
/* Last value, used by profile streaming. */
272 /* A structure to group all the per-function control flow graph data.
273 The x_* prefixing is necessary because otherwise references to the
274 fields of this struct are interpreted as the defines for backward
275 source compatibility following the definition of this struct. */
276 struct GTY(()) control_flow_graph
{
277 /* Block pointers for the exit and entry of a function.
278 These are always the head and tail of the basic block list. */
279 basic_block x_entry_block_ptr
;
280 basic_block x_exit_block_ptr
;
282 /* Index by basic block number, get basic block struct info. */
283 vec
<basic_block
, va_gc
> *x_basic_block_info
;
285 /* Number of basic blocks in this flow graph. */
286 int x_n_basic_blocks
;
288 /* Number of edges in this flow graph. */
291 /* The first free basic block number. */
292 int x_last_basic_block
;
294 /* UIDs for LABEL_DECLs. */
297 /* Mapping of labels to their associated blocks. At present
298 only used for the gimple CFG. */
299 vec
<basic_block
, va_gc
> *x_label_to_block_map
;
301 enum profile_status_d x_profile_status
;
303 /* Whether the dominators and the postdominators are available. */
304 enum dom_state x_dom_computed
[2];
306 /* Number of basic blocks in the dominance tree. */
307 unsigned x_n_bbs_in_dom_tree
[2];
309 /* Maximal number of entities in the single jumptable. Used to estimate
310 final flowgraph size. */
311 int max_jumptable_ents
;
314 /* Defines for accessing the fields of the CFG structure for function FN. */
315 #define ENTRY_BLOCK_PTR_FOR_FUNCTION(FN) ((FN)->cfg->x_entry_block_ptr)
316 #define EXIT_BLOCK_PTR_FOR_FUNCTION(FN) ((FN)->cfg->x_exit_block_ptr)
317 #define basic_block_info_for_function(FN) ((FN)->cfg->x_basic_block_info)
318 #define n_basic_blocks_for_function(FN) ((FN)->cfg->x_n_basic_blocks)
319 #define n_edges_for_function(FN) ((FN)->cfg->x_n_edges)
320 #define last_basic_block_for_function(FN) ((FN)->cfg->x_last_basic_block)
321 #define label_to_block_map_for_function(FN) ((FN)->cfg->x_label_to_block_map)
322 #define profile_status_for_function(FN) ((FN)->cfg->x_profile_status)
324 #define BASIC_BLOCK_FOR_FUNCTION(FN,N) \
325 ((*basic_block_info_for_function (FN))[(N)])
326 #define SET_BASIC_BLOCK_FOR_FUNCTION(FN,N,BB) \
327 ((*basic_block_info_for_function (FN))[(N)] = (BB))
329 /* Defines for textual backward source compatibility. */
330 #define ENTRY_BLOCK_PTR (cfun->cfg->x_entry_block_ptr)
331 #define EXIT_BLOCK_PTR (cfun->cfg->x_exit_block_ptr)
332 #define basic_block_info (cfun->cfg->x_basic_block_info)
333 #define n_basic_blocks (cfun->cfg->x_n_basic_blocks)
334 #define n_edges (cfun->cfg->x_n_edges)
335 #define last_basic_block (cfun->cfg->x_last_basic_block)
336 #define label_to_block_map (cfun->cfg->x_label_to_block_map)
337 #define profile_status (cfun->cfg->x_profile_status)
339 #define BASIC_BLOCK(N) ((*basic_block_info)[(N)])
340 #define SET_BASIC_BLOCK(N,BB) ((*basic_block_info)[(N)] = (BB))
342 /* For iterating over basic blocks. */
343 #define FOR_BB_BETWEEN(BB, FROM, TO, DIR) \
344 for (BB = FROM; BB != TO; BB = BB->DIR)
346 #define FOR_EACH_BB_FN(BB, FN) \
347 FOR_BB_BETWEEN (BB, (FN)->cfg->x_entry_block_ptr->next_bb, (FN)->cfg->x_exit_block_ptr, next_bb)
349 #define FOR_EACH_BB(BB) FOR_EACH_BB_FN (BB, cfun)
351 #define FOR_EACH_BB_REVERSE_FN(BB, FN) \
352 FOR_BB_BETWEEN (BB, (FN)->cfg->x_exit_block_ptr->prev_bb, (FN)->cfg->x_entry_block_ptr, prev_bb)
354 #define FOR_EACH_BB_REVERSE(BB) FOR_EACH_BB_REVERSE_FN (BB, cfun)
356 /* For iterating over insns in basic block. */
357 #define FOR_BB_INSNS(BB, INSN) \
358 for ((INSN) = BB_HEAD (BB); \
359 (INSN) && (INSN) != NEXT_INSN (BB_END (BB)); \
360 (INSN) = NEXT_INSN (INSN))
362 /* For iterating over insns in basic block when we might remove the
364 #define FOR_BB_INSNS_SAFE(BB, INSN, CURR) \
365 for ((INSN) = BB_HEAD (BB), (CURR) = (INSN) ? NEXT_INSN ((INSN)): NULL; \
366 (INSN) && (INSN) != NEXT_INSN (BB_END (BB)); \
367 (INSN) = (CURR), (CURR) = (INSN) ? NEXT_INSN ((INSN)) : NULL)
369 #define FOR_BB_INSNS_REVERSE(BB, INSN) \
370 for ((INSN) = BB_END (BB); \
371 (INSN) && (INSN) != PREV_INSN (BB_HEAD (BB)); \
372 (INSN) = PREV_INSN (INSN))
374 #define FOR_BB_INSNS_REVERSE_SAFE(BB, INSN, CURR) \
375 for ((INSN) = BB_END (BB),(CURR) = (INSN) ? PREV_INSN ((INSN)) : NULL; \
376 (INSN) && (INSN) != PREV_INSN (BB_HEAD (BB)); \
377 (INSN) = (CURR), (CURR) = (INSN) ? PREV_INSN ((INSN)) : NULL)
379 /* Cycles through _all_ basic blocks, even the fake ones (entry and
382 #define FOR_ALL_BB(BB) \
383 for (BB = ENTRY_BLOCK_PTR; BB; BB = BB->next_bb)
385 #define FOR_ALL_BB_FN(BB, FN) \
386 for (BB = ENTRY_BLOCK_PTR_FOR_FUNCTION (FN); BB; BB = BB->next_bb)
389 /* Stuff for recording basic block info. */
391 #define BB_HEAD(B) (B)->il.x.head_
392 #define BB_END(B) (B)->il.x.rtl->end_
393 #define BB_HEADER(B) (B)->il.x.rtl->header_
394 #define BB_FOOTER(B) (B)->il.x.rtl->footer_
396 /* Special block numbers [markers] for entry and exit.
397 Neither of them is supposed to hold actual statements. */
398 #define ENTRY_BLOCK (0)
399 #define EXIT_BLOCK (1)
401 /* The two blocks that are always in the cfg. */
402 #define NUM_FIXED_BLOCKS (2)
404 #define set_block_for_insn(INSN, BB) (BLOCK_FOR_INSN (INSN) = BB)
406 extern void compute_bb_for_insn (void);
407 extern unsigned int free_bb_for_insn (void);
408 extern void update_bb_for_insn (basic_block
);
410 extern void insert_insn_on_edge (rtx
, edge
);
411 basic_block
split_edge_and_insert (edge
, rtx
);
413 extern void commit_one_edge_insertion (edge e
);
414 extern void commit_edge_insertions (void);
416 extern edge
unchecked_make_edge (basic_block
, basic_block
, int);
417 extern edge
cached_make_edge (sbitmap
, basic_block
, basic_block
, int);
418 extern edge
make_edge (basic_block
, basic_block
, int);
419 extern edge
make_single_succ_edge (basic_block
, basic_block
, int);
420 extern void remove_edge_raw (edge
);
421 extern void redirect_edge_succ (edge
, basic_block
);
422 extern edge
redirect_edge_succ_nodup (edge
, basic_block
);
423 extern void redirect_edge_pred (edge
, basic_block
);
424 extern basic_block
create_basic_block_structure (rtx
, rtx
, rtx
, basic_block
);
425 extern void clear_bb_flags (void);
426 extern void dump_bb_info (FILE *, basic_block
, int, int, bool, bool);
427 extern void dump_edge_info (FILE *, edge
, int, int);
428 extern void debug (edge_def
&ref
);
429 extern void debug (edge_def
*ptr
);
430 extern void brief_dump_cfg (FILE *, int);
431 extern void clear_edges (void);
432 extern void scale_bbs_frequencies_int (basic_block
*, int, int, int);
433 extern void scale_bbs_frequencies_gcov_type (basic_block
*, int, gcov_type
,
436 /* Structure to group all of the information to process IF-THEN and
437 IF-THEN-ELSE blocks for the conditional execution support. This
438 needs to be in a public file in case the IFCVT macros call
439 functions passing the ce_if_block data structure. */
441 typedef struct ce_if_block
443 basic_block test_bb
; /* First test block. */
444 basic_block then_bb
; /* THEN block. */
445 basic_block else_bb
; /* ELSE block or NULL. */
446 basic_block join_bb
; /* Join THEN/ELSE blocks. */
447 basic_block last_test_bb
; /* Last bb to hold && or || tests. */
448 int num_multiple_test_blocks
; /* # of && and || basic blocks. */
449 int num_and_and_blocks
; /* # of && blocks. */
450 int num_or_or_blocks
; /* # of || blocks. */
451 int num_multiple_test_insns
; /* # of insns in && and || blocks. */
452 int and_and_p
; /* Complex test is &&. */
453 int num_then_insns
; /* # of insns in THEN block. */
454 int num_else_insns
; /* # of insns in ELSE block. */
455 int pass
; /* Pass number. */
458 /* This structure maintains an edge list vector. */
459 /* FIXME: Make this a vec<edge>. */
466 /* Class to compute and manage control dependences on an edge-list. */
467 class control_dependences
470 control_dependences (edge_list
*);
471 ~control_dependences ();
472 bitmap
get_edges_dependent_on (int);
476 void set_control_dependence_map_bit (basic_block
, int);
477 void clear_control_dependence_bitmap (basic_block
);
478 void find_control_dependence (int);
479 vec
<bitmap
> control_dependence_map
;
483 /* The base value for branch probability notes and edge probabilities. */
484 #define REG_BR_PROB_BASE 10000
486 /* This is the value which indicates no edge is present. */
487 #define EDGE_INDEX_NO_EDGE -1
489 /* EDGE_INDEX returns an integer index for an edge, or EDGE_INDEX_NO_EDGE
490 if there is no edge between the 2 basic blocks. */
491 #define EDGE_INDEX(el, pred, succ) (find_edge_index ((el), (pred), (succ)))
493 /* INDEX_EDGE_PRED_BB and INDEX_EDGE_SUCC_BB return a pointer to the basic
494 block which is either the pred or succ end of the indexed edge. */
495 #define INDEX_EDGE_PRED_BB(el, index) ((el)->index_to_edge[(index)]->src)
496 #define INDEX_EDGE_SUCC_BB(el, index) ((el)->index_to_edge[(index)]->dest)
498 /* INDEX_EDGE returns a pointer to the edge. */
499 #define INDEX_EDGE(el, index) ((el)->index_to_edge[(index)])
501 /* Number of edges in the compressed edge list. */
502 #define NUM_EDGES(el) ((el)->num_edges)
504 /* BB is assumed to contain conditional jump. Return the fallthru edge. */
505 #define FALLTHRU_EDGE(bb) (EDGE_SUCC ((bb), 0)->flags & EDGE_FALLTHRU \
506 ? EDGE_SUCC ((bb), 0) : EDGE_SUCC ((bb), 1))
508 /* BB is assumed to contain conditional jump. Return the branch edge. */
509 #define BRANCH_EDGE(bb) (EDGE_SUCC ((bb), 0)->flags & EDGE_FALLTHRU \
510 ? EDGE_SUCC ((bb), 1) : EDGE_SUCC ((bb), 0))
512 #define RDIV(X,Y) (((X) + (Y) / 2) / (Y))
513 /* Return expected execution frequency of the edge E. */
514 #define EDGE_FREQUENCY(e) RDIV ((e)->src->frequency * (e)->probability, \
517 /* Compute a scale factor (or probability) suitable for scaling of
518 gcov_type values via apply_probability() and apply_scale(). */
519 #define GCOV_COMPUTE_SCALE(num,den) \
520 ((den) ? RDIV ((num) * REG_BR_PROB_BASE, (den)) : REG_BR_PROB_BASE)
522 /* Return nonzero if edge is critical. */
523 #define EDGE_CRITICAL_P(e) (EDGE_COUNT ((e)->src->succs) >= 2 \
524 && EDGE_COUNT ((e)->dest->preds) >= 2)
526 #define EDGE_COUNT(ev) vec_safe_length (ev)
527 #define EDGE_I(ev,i) (*ev)[(i)]
528 #define EDGE_PRED(bb,i) (*(bb)->preds)[(i)]
529 #define EDGE_SUCC(bb,i) (*(bb)->succs)[(i)]
531 /* Returns true if BB has precisely one successor. */
534 single_succ_p (const_basic_block bb
)
536 return EDGE_COUNT (bb
->succs
) == 1;
539 /* Returns true if BB has precisely one predecessor. */
542 single_pred_p (const_basic_block bb
)
544 return EDGE_COUNT (bb
->preds
) == 1;
547 /* Returns the single successor edge of basic block BB. Aborts if
548 BB does not have exactly one successor. */
551 single_succ_edge (const_basic_block bb
)
553 gcc_checking_assert (single_succ_p (bb
));
554 return EDGE_SUCC (bb
, 0);
557 /* Returns the single predecessor edge of basic block BB. Aborts
558 if BB does not have exactly one predecessor. */
561 single_pred_edge (const_basic_block bb
)
563 gcc_checking_assert (single_pred_p (bb
));
564 return EDGE_PRED (bb
, 0);
567 /* Returns the single successor block of basic block BB. Aborts
568 if BB does not have exactly one successor. */
570 static inline basic_block
571 single_succ (const_basic_block bb
)
573 return single_succ_edge (bb
)->dest
;
576 /* Returns the single predecessor block of basic block BB. Aborts
577 if BB does not have exactly one predecessor.*/
579 static inline basic_block
580 single_pred (const_basic_block bb
)
582 return single_pred_edge (bb
)->src
;
585 /* Iterator object for edges. */
589 vec
<edge
, va_gc
> **container
;
592 static inline vec
<edge
, va_gc
> *
593 ei_container (edge_iterator i
)
595 gcc_checking_assert (i
.container
);
599 #define ei_start(iter) ei_start_1 (&(iter))
600 #define ei_last(iter) ei_last_1 (&(iter))
602 /* Return an iterator pointing to the start of an edge vector. */
603 static inline edge_iterator
604 ei_start_1 (vec
<edge
, va_gc
> **ev
)
614 /* Return an iterator pointing to the last element of an edge
616 static inline edge_iterator
617 ei_last_1 (vec
<edge
, va_gc
> **ev
)
621 i
.index
= EDGE_COUNT (*ev
) - 1;
627 /* Is the iterator `i' at the end of the sequence? */
629 ei_end_p (edge_iterator i
)
631 return (i
.index
== EDGE_COUNT (ei_container (i
)));
634 /* Is the iterator `i' at one position before the end of the
637 ei_one_before_end_p (edge_iterator i
)
639 return (i
.index
+ 1 == EDGE_COUNT (ei_container (i
)));
642 /* Advance the iterator to the next element. */
644 ei_next (edge_iterator
*i
)
646 gcc_checking_assert (i
->index
< EDGE_COUNT (ei_container (*i
)));
650 /* Move the iterator to the previous element. */
652 ei_prev (edge_iterator
*i
)
654 gcc_checking_assert (i
->index
> 0);
658 /* Return the edge pointed to by the iterator `i'. */
660 ei_edge (edge_iterator i
)
662 return EDGE_I (ei_container (i
), i
.index
);
665 /* Return an edge pointed to by the iterator. Do it safely so that
666 NULL is returned when the iterator is pointing at the end of the
669 ei_safe_edge (edge_iterator i
)
671 return !ei_end_p (i
) ? ei_edge (i
) : NULL
;
674 /* Return 1 if we should continue to iterate. Return 0 otherwise.
675 *Edge P is set to the next edge if we are to continue to iterate
676 and NULL otherwise. */
679 ei_cond (edge_iterator ei
, edge
*p
)
693 /* This macro serves as a convenient way to iterate each edge in a
694 vector of predecessor or successor edges. It must not be used when
695 an element might be removed during the traversal, otherwise
696 elements will be missed. Instead, use a for-loop like that shown
697 in the following pseudo-code:
699 FOR (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
708 #define FOR_EACH_EDGE(EDGE,ITER,EDGE_VEC) \
709 for ((ITER) = ei_start ((EDGE_VEC)); \
710 ei_cond ((ITER), &(EDGE)); \
713 #define CLEANUP_EXPENSIVE 1 /* Do relatively expensive optimizations
714 except for edge forwarding */
715 #define CLEANUP_CROSSJUMP 2 /* Do crossjumping. */
716 #define CLEANUP_POST_REGSTACK 4 /* We run after reg-stack and need
717 to care REG_DEAD notes. */
718 #define CLEANUP_THREADING 8 /* Do jump threading. */
719 #define CLEANUP_NO_INSN_DEL 16 /* Do not try to delete trivially dead
721 #define CLEANUP_CFGLAYOUT 32 /* Do cleanup in cfglayout mode. */
722 #define CLEANUP_CFG_CHANGED 64 /* The caller changed the CFG. */
725 extern void bitmap_intersection_of_succs (sbitmap
, sbitmap
*, basic_block
);
726 extern void bitmap_intersection_of_preds (sbitmap
, sbitmap
*, basic_block
);
727 extern void bitmap_union_of_succs (sbitmap
, sbitmap
*, basic_block
);
728 extern void bitmap_union_of_preds (sbitmap
, sbitmap
*, basic_block
);
731 extern struct edge_list
*pre_edge_lcm (int, sbitmap
*, sbitmap
*,
732 sbitmap
*, sbitmap
*, sbitmap
**,
734 extern struct edge_list
*pre_edge_rev_lcm (int, sbitmap
*,
735 sbitmap
*, sbitmap
*,
736 sbitmap
*, sbitmap
**,
738 extern void compute_available (sbitmap
*, sbitmap
*, sbitmap
*, sbitmap
*);
741 extern bool maybe_hot_bb_p (struct function
*, const_basic_block
);
742 extern bool maybe_hot_edge_p (edge
);
743 extern bool probably_never_executed_bb_p (struct function
*, const_basic_block
);
744 extern bool probably_never_executed_edge_p (struct function
*, edge
);
745 extern bool optimize_bb_for_size_p (const_basic_block
);
746 extern bool optimize_bb_for_speed_p (const_basic_block
);
747 extern bool optimize_edge_for_size_p (edge
);
748 extern bool optimize_edge_for_speed_p (edge
);
749 extern bool optimize_loop_for_size_p (struct loop
*);
750 extern bool optimize_loop_for_speed_p (struct loop
*);
751 extern bool optimize_loop_nest_for_size_p (struct loop
*);
752 extern bool optimize_loop_nest_for_speed_p (struct loop
*);
753 extern bool gimple_predicted_by_p (const_basic_block
, enum br_predictor
);
754 extern bool rtl_predicted_by_p (const_basic_block
, enum br_predictor
);
755 extern void gimple_predict_edge (edge
, enum br_predictor
, int);
756 extern void rtl_predict_edge (edge
, enum br_predictor
, int);
757 extern void predict_edge_def (edge
, enum br_predictor
, enum prediction
);
758 extern void guess_outgoing_edge_probabilities (basic_block
);
759 extern void remove_predictions_associated_with_edge (edge
);
760 extern bool edge_probability_reliable_p (const_edge
);
761 extern bool br_prob_note_reliable_p (const_rtx
);
762 extern bool predictable_edge_p (edge
);
765 extern void init_flow (struct function
*);
766 extern void debug_bb (basic_block
);
767 extern basic_block
debug_bb_n (int);
768 extern void dump_flow_info (FILE *, int);
769 extern void expunge_block (basic_block
);
770 extern void link_block (basic_block
, basic_block
);
771 extern void unlink_block (basic_block
);
772 extern void compact_blocks (void);
773 extern basic_block
alloc_block (void);
774 extern void alloc_aux_for_blocks (int);
775 extern void clear_aux_for_blocks (void);
776 extern void free_aux_for_blocks (void);
777 extern void alloc_aux_for_edge (edge
, int);
778 extern void alloc_aux_for_edges (int);
779 extern void clear_aux_for_edges (void);
780 extern void free_aux_for_edges (void);
783 extern void find_unreachable_blocks (void);
784 extern bool mark_dfs_back_edges (void);
785 struct edge_list
* create_edge_list (void);
786 void free_edge_list (struct edge_list
*);
787 void print_edge_list (FILE *, struct edge_list
*);
788 void verify_edge_list (FILE *, struct edge_list
*);
789 int find_edge_index (struct edge_list
*, basic_block
, basic_block
);
790 edge
find_edge (basic_block
, basic_block
);
791 extern void remove_fake_edges (void);
792 extern void remove_fake_exit_edges (void);
793 extern void add_noreturn_fake_exit_edges (void);
794 extern void connect_infinite_loops_to_exit (void);
795 extern int post_order_compute (int *, bool, bool);
796 extern basic_block
dfs_find_deadend (basic_block
);
797 extern int inverted_post_order_compute (int *);
798 extern int pre_and_rev_post_order_compute (int *, int *, bool);
799 extern int dfs_enumerate_from (basic_block
, int,
800 bool (*)(const_basic_block
, const void *),
801 basic_block
*, int, const void *);
802 extern void compute_dominance_frontiers (struct bitmap_head_def
*);
803 extern bitmap
compute_idf (bitmap
, struct bitmap_head_def
*);
804 extern basic_block
* single_pred_before_succ_order (void);
807 extern rtx
block_label (basic_block
);
808 extern rtx
bb_note (basic_block
);
809 extern bool purge_all_dead_edges (void);
810 extern bool purge_dead_edges (basic_block
);
811 extern bool fixup_abnormal_edges (void);
812 extern basic_block
force_nonfallthru_and_redirect (edge
, basic_block
, rtx
);
813 extern bool contains_no_active_insn_p (const_basic_block
);
814 extern bool forwarder_block_p (const_basic_block
);
815 extern bool can_fallthru (basic_block
, basic_block
);
816 extern void emit_barrier_after_bb (basic_block bb
);
817 extern void fixup_partitions (void);
820 extern void find_many_sub_basic_blocks (sbitmap
);
821 extern void rtl_make_eh_edge (sbitmap
, basic_block
, rtx
);
823 enum replace_direction
{ dir_none
, dir_forward
, dir_backward
, dir_both
};
825 /* In cfgcleanup.c. */
826 extern bool cleanup_cfg (int);
827 extern int flow_find_cross_jump (basic_block
, basic_block
, rtx
*, rtx
*,
828 enum replace_direction
*);
829 extern int flow_find_head_matching_sequence (basic_block
, basic_block
,
832 extern bool delete_unreachable_blocks (void);
834 extern void update_br_prob_note (basic_block
);
835 extern bool inside_basic_block_p (const_rtx
);
836 extern bool control_flow_insn_p (const_rtx
);
837 extern rtx
get_last_bb_insn (basic_block
);
844 CDI_POST_DOMINATORS
= 2
847 extern enum dom_state
dom_info_state (enum cdi_direction
);
848 extern void set_dom_info_availability (enum cdi_direction
, enum dom_state
);
849 extern bool dom_info_available_p (enum cdi_direction
);
850 extern void calculate_dominance_info (enum cdi_direction
);
851 extern void free_dominance_info (enum cdi_direction
);
852 extern basic_block
nearest_common_dominator (enum cdi_direction
,
853 basic_block
, basic_block
);
854 extern basic_block
nearest_common_dominator_for_set (enum cdi_direction
,
856 extern void set_immediate_dominator (enum cdi_direction
, basic_block
,
858 extern basic_block
get_immediate_dominator (enum cdi_direction
, basic_block
);
859 extern bool dominated_by_p (enum cdi_direction
, const_basic_block
, const_basic_block
);
860 extern vec
<basic_block
> get_dominated_by (enum cdi_direction
, basic_block
);
861 extern vec
<basic_block
> get_dominated_by_region (enum cdi_direction
,
864 extern vec
<basic_block
> get_dominated_to_depth (enum cdi_direction
,
866 extern vec
<basic_block
> get_all_dominated_blocks (enum cdi_direction
,
868 extern void add_to_dominance_info (enum cdi_direction
, basic_block
);
869 extern void delete_from_dominance_info (enum cdi_direction
, basic_block
);
870 basic_block
recompute_dominator (enum cdi_direction
, basic_block
);
871 extern void redirect_immediate_dominators (enum cdi_direction
, basic_block
,
873 extern void iterate_fix_dominators (enum cdi_direction
,
874 vec
<basic_block
> , bool);
875 extern void verify_dominators (enum cdi_direction
);
876 extern basic_block
first_dom_son (enum cdi_direction
, basic_block
);
877 extern basic_block
next_dom_son (enum cdi_direction
, basic_block
);
878 unsigned bb_dom_dfs_in (enum cdi_direction
, basic_block
);
879 unsigned bb_dom_dfs_out (enum cdi_direction
, basic_block
);
881 extern edge
try_redirect_by_replacing_jump (edge
, basic_block
, bool);
882 extern void break_superblocks (void);
883 extern void relink_block_chain (bool);
884 extern void update_bb_profile_for_threading (basic_block
, int, gcov_type
, edge
);
885 extern void init_rtl_bb_info (basic_block
);
887 extern void initialize_original_copy_tables (void);
888 extern void free_original_copy_tables (void);
889 extern void set_bb_original (basic_block
, basic_block
);
890 extern basic_block
get_bb_original (basic_block
);
891 extern void set_bb_copy (basic_block
, basic_block
);
892 extern basic_block
get_bb_copy (basic_block
);
893 void set_loop_copy (struct loop
*, struct loop
*);
894 struct loop
*get_loop_copy (struct loop
*);
896 #include "cfghooks.h"
898 /* Return true when one of the predecessor edges of BB is marked with EDGE_EH. */
900 bb_has_eh_pred (basic_block bb
)
905 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
907 if (e
->flags
& EDGE_EH
)
913 /* Return true when one of the predecessor edges of BB is marked with EDGE_ABNORMAL. */
915 bb_has_abnormal_pred (basic_block bb
)
920 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
922 if (e
->flags
& EDGE_ABNORMAL
)
928 /* Return the fallthru edge in EDGES if it exists, NULL otherwise. */
930 find_fallthru_edge (vec
<edge
, va_gc
> *edges
)
935 FOR_EACH_EDGE (e
, ei
, edges
)
936 if (e
->flags
& EDGE_FALLTHRU
)
942 /* In cfgloopmanip.c. */
943 extern edge mfb_kj_edge
;
944 extern bool mfb_keep_just (edge
);
946 /* In cfgexpand.c. */
947 extern void rtl_profile_for_bb (basic_block
);
948 extern void rtl_profile_for_edge (edge
);
949 extern void default_rtl_profile (void);
952 typedef struct gcov_working_set_info gcov_working_set_t
;
953 extern gcov_working_set_t
*find_working_set (unsigned pct_times_10
);
955 /* Check tha probability is sane. */
958 check_probability (int prob
)
960 gcc_checking_assert (prob
>= 0 && prob
<= REG_BR_PROB_BASE
);
963 /* Given PROB1 and PROB2, return PROB1*PROB2/REG_BR_PROB_BASE.
964 Used to combine BB probabilities. */
967 combine_probabilities (int prob1
, int prob2
)
969 check_probability (prob1
);
970 check_probability (prob2
);
971 return RDIV (prob1
* prob2
, REG_BR_PROB_BASE
);
974 /* Apply scale factor SCALE on frequency or count FREQ. Use this
975 interface when potentially scaling up, so that SCALE is not
976 constrained to be < REG_BR_PROB_BASE. */
978 static inline gcov_type
979 apply_scale (gcov_type freq
, gcov_type scale
)
981 return RDIV (freq
* scale
, REG_BR_PROB_BASE
);
984 /* Apply probability PROB on frequency or count FREQ. */
986 static inline gcov_type
987 apply_probability (gcov_type freq
, int prob
)
989 check_probability (prob
);
990 return apply_scale (freq
, prob
);
993 /* Return inverse probability for PROB. */
996 inverse_probability (int prob1
)
998 check_probability (prob1
);
999 return REG_BR_PROB_BASE
- prob1
;
1001 #endif /* GCC_BASIC_BLOCK_H */