* pt.c (lookup_template_class_1): Splice out abi_tag attribute if
[official-gcc.git] / gcc / cfg.c
blob6070d9ed2205cc0dcc858a559e07535b395ef144
1 /* Control flow graph manipulation code for GNU compiler.
2 Copyright (C) 1987-2014 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
9 version.
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
14 for more details.
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 /* This file contains low level functions to manipulate the CFG and
21 analyze it. All other modules should not transform the data structure
22 directly and use abstraction instead. The file is supposed to be
23 ordered bottom-up and should not contain any code dependent on a
24 particular intermediate language (RTL or trees).
26 Available functionality:
27 - Initialization/deallocation
28 init_flow, clear_edges
29 - Low level basic block manipulation
30 alloc_block, expunge_block
31 - Edge manipulation
32 make_edge, make_single_succ_edge, cached_make_edge, remove_edge
33 - Low level edge redirection (without updating instruction chain)
34 redirect_edge_succ, redirect_edge_succ_nodup, redirect_edge_pred
35 - Dumping and debugging
36 dump_flow_info, debug_flow_info, dump_edge_info
37 - Allocation of AUX fields for basic blocks
38 alloc_aux_for_blocks, free_aux_for_blocks, alloc_aux_for_block
39 - clear_bb_flags
40 - Consistency checking
41 verify_flow_info
42 - Dumping and debugging
43 print_rtl_with_bb, dump_bb, debug_bb, debug_bb_n
45 TODO: Document these "Available functionality" functions in the files
46 that implement them.
49 #include "config.h"
50 #include "system.h"
51 #include "coretypes.h"
52 #include "obstack.h"
53 #include "ggc.h"
54 #include "hash-table.h"
55 #include "alloc-pool.h"
56 #include "tree.h"
57 #include "basic-block.h"
58 #include "df.h"
59 #include "cfgloop.h" /* FIXME: For struct loop. */
60 #include "dumpfile.h"
63 #define RDIV(X,Y) (((X) + (Y) / 2) / (Y))
65 /* Called once at initialization time. */
67 void
68 init_flow (struct function *the_fun)
70 if (!the_fun->cfg)
71 the_fun->cfg = ggc_cleared_alloc<control_flow_graph> ();
72 n_edges_for_fn (the_fun) = 0;
73 ENTRY_BLOCK_PTR_FOR_FN (the_fun)
74 = ggc_cleared_alloc<basic_block_def> ();
75 ENTRY_BLOCK_PTR_FOR_FN (the_fun)->index = ENTRY_BLOCK;
76 EXIT_BLOCK_PTR_FOR_FN (the_fun)
77 = ggc_cleared_alloc<basic_block_def> ();
78 EXIT_BLOCK_PTR_FOR_FN (the_fun)->index = EXIT_BLOCK;
79 ENTRY_BLOCK_PTR_FOR_FN (the_fun)->next_bb
80 = EXIT_BLOCK_PTR_FOR_FN (the_fun);
81 EXIT_BLOCK_PTR_FOR_FN (the_fun)->prev_bb
82 = ENTRY_BLOCK_PTR_FOR_FN (the_fun);
85 /* Helper function for remove_edge and clear_edges. Frees edge structure
86 without actually removing it from the pred/succ arrays. */
88 static void
89 free_edge (edge e)
91 n_edges_for_fn (cfun)--;
92 ggc_free (e);
95 /* Free the memory associated with the edge structures. */
97 void
98 clear_edges (void)
100 basic_block bb;
101 edge e;
102 edge_iterator ei;
104 FOR_EACH_BB_FN (bb, cfun)
106 FOR_EACH_EDGE (e, ei, bb->succs)
107 free_edge (e);
108 vec_safe_truncate (bb->succs, 0);
109 vec_safe_truncate (bb->preds, 0);
112 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs)
113 free_edge (e);
114 vec_safe_truncate (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds, 0);
115 vec_safe_truncate (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs, 0);
117 gcc_assert (!n_edges_for_fn (cfun));
120 /* Allocate memory for basic_block. */
122 basic_block
123 alloc_block (void)
125 basic_block bb;
126 bb = ggc_cleared_alloc<basic_block_def> ();
127 return bb;
130 /* Link block B to chain after AFTER. */
131 void
132 link_block (basic_block b, basic_block after)
134 b->next_bb = after->next_bb;
135 b->prev_bb = after;
136 after->next_bb = b;
137 b->next_bb->prev_bb = b;
140 /* Unlink block B from chain. */
141 void
142 unlink_block (basic_block b)
144 b->next_bb->prev_bb = b->prev_bb;
145 b->prev_bb->next_bb = b->next_bb;
146 b->prev_bb = NULL;
147 b->next_bb = NULL;
150 /* Sequentially order blocks and compact the arrays. */
151 void
152 compact_blocks (void)
154 int i;
156 SET_BASIC_BLOCK_FOR_FN (cfun, ENTRY_BLOCK, ENTRY_BLOCK_PTR_FOR_FN (cfun));
157 SET_BASIC_BLOCK_FOR_FN (cfun, EXIT_BLOCK, EXIT_BLOCK_PTR_FOR_FN (cfun));
159 if (df)
160 df_compact_blocks ();
161 else
163 basic_block bb;
165 i = NUM_FIXED_BLOCKS;
166 FOR_EACH_BB_FN (bb, cfun)
168 SET_BASIC_BLOCK_FOR_FN (cfun, i, bb);
169 bb->index = i;
170 i++;
172 gcc_assert (i == n_basic_blocks_for_fn (cfun));
174 for (; i < last_basic_block_for_fn (cfun); i++)
175 SET_BASIC_BLOCK_FOR_FN (cfun, i, NULL);
177 last_basic_block_for_fn (cfun) = n_basic_blocks_for_fn (cfun);
180 /* Remove block B from the basic block array. */
182 void
183 expunge_block (basic_block b)
185 unlink_block (b);
186 SET_BASIC_BLOCK_FOR_FN (cfun, b->index, NULL);
187 n_basic_blocks_for_fn (cfun)--;
188 /* We should be able to ggc_free here, but we are not.
189 The dead SSA_NAMES are left pointing to dead statements that are pointing
190 to dead basic blocks making garbage collector to die.
191 We should be able to release all dead SSA_NAMES and at the same time we should
192 clear out BB pointer of dead statements consistently. */
195 /* Connect E to E->src. */
197 static inline void
198 connect_src (edge e)
200 vec_safe_push (e->src->succs, e);
201 df_mark_solutions_dirty ();
204 /* Connect E to E->dest. */
206 static inline void
207 connect_dest (edge e)
209 basic_block dest = e->dest;
210 vec_safe_push (dest->preds, e);
211 e->dest_idx = EDGE_COUNT (dest->preds) - 1;
212 df_mark_solutions_dirty ();
215 /* Disconnect edge E from E->src. */
217 static inline void
218 disconnect_src (edge e)
220 basic_block src = e->src;
221 edge_iterator ei;
222 edge tmp;
224 for (ei = ei_start (src->succs); (tmp = ei_safe_edge (ei)); )
226 if (tmp == e)
228 src->succs->unordered_remove (ei.index);
229 df_mark_solutions_dirty ();
230 return;
232 else
233 ei_next (&ei);
236 gcc_unreachable ();
239 /* Disconnect edge E from E->dest. */
241 static inline void
242 disconnect_dest (edge e)
244 basic_block dest = e->dest;
245 unsigned int dest_idx = e->dest_idx;
247 dest->preds->unordered_remove (dest_idx);
249 /* If we removed an edge in the middle of the edge vector, we need
250 to update dest_idx of the edge that moved into the "hole". */
251 if (dest_idx < EDGE_COUNT (dest->preds))
252 EDGE_PRED (dest, dest_idx)->dest_idx = dest_idx;
253 df_mark_solutions_dirty ();
256 /* Create an edge connecting SRC and DEST with flags FLAGS. Return newly
257 created edge. Use this only if you are sure that this edge can't
258 possibly already exist. */
260 edge
261 unchecked_make_edge (basic_block src, basic_block dst, int flags)
263 edge e;
264 e = ggc_cleared_alloc<edge_def> ();
265 n_edges_for_fn (cfun)++;
267 e->src = src;
268 e->dest = dst;
269 e->flags = flags;
271 connect_src (e);
272 connect_dest (e);
274 execute_on_growing_pred (e);
275 return e;
278 /* Create an edge connecting SRC and DST with FLAGS optionally using
279 edge cache CACHE. Return the new edge, NULL if already exist. */
281 edge
282 cached_make_edge (sbitmap edge_cache, basic_block src, basic_block dst, int flags)
284 if (edge_cache == NULL
285 || src == ENTRY_BLOCK_PTR_FOR_FN (cfun)
286 || dst == EXIT_BLOCK_PTR_FOR_FN (cfun))
287 return make_edge (src, dst, flags);
289 /* Does the requested edge already exist? */
290 if (! bitmap_bit_p (edge_cache, dst->index))
292 /* The edge does not exist. Create one and update the
293 cache. */
294 bitmap_set_bit (edge_cache, dst->index);
295 return unchecked_make_edge (src, dst, flags);
298 /* At this point, we know that the requested edge exists. Adjust
299 flags if necessary. */
300 if (flags)
302 edge e = find_edge (src, dst);
303 e->flags |= flags;
306 return NULL;
309 /* Create an edge connecting SRC and DEST with flags FLAGS. Return newly
310 created edge or NULL if already exist. */
312 edge
313 make_edge (basic_block src, basic_block dest, int flags)
315 edge e = find_edge (src, dest);
317 /* Make sure we don't add duplicate edges. */
318 if (e)
320 e->flags |= flags;
321 return NULL;
324 return unchecked_make_edge (src, dest, flags);
327 /* Create an edge connecting SRC to DEST and set probability by knowing
328 that it is the single edge leaving SRC. */
330 edge
331 make_single_succ_edge (basic_block src, basic_block dest, int flags)
333 edge e = make_edge (src, dest, flags);
335 e->probability = REG_BR_PROB_BASE;
336 e->count = src->count;
337 return e;
340 /* This function will remove an edge from the flow graph. */
342 void
343 remove_edge_raw (edge e)
345 remove_predictions_associated_with_edge (e);
346 execute_on_shrinking_pred (e);
348 disconnect_src (e);
349 disconnect_dest (e);
351 free_edge (e);
354 /* Redirect an edge's successor from one block to another. */
356 void
357 redirect_edge_succ (edge e, basic_block new_succ)
359 execute_on_shrinking_pred (e);
361 disconnect_dest (e);
363 e->dest = new_succ;
365 /* Reconnect the edge to the new successor block. */
366 connect_dest (e);
368 execute_on_growing_pred (e);
371 /* Redirect an edge's predecessor from one block to another. */
373 void
374 redirect_edge_pred (edge e, basic_block new_pred)
376 disconnect_src (e);
378 e->src = new_pred;
380 /* Reconnect the edge to the new predecessor block. */
381 connect_src (e);
384 /* Clear all basic block flags that do not have to be preserved. */
385 void
386 clear_bb_flags (void)
388 basic_block bb;
390 FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun), NULL, next_bb)
391 bb->flags &= BB_FLAGS_TO_PRESERVE;
394 /* Check the consistency of profile information. We can't do that
395 in verify_flow_info, as the counts may get invalid for incompletely
396 solved graphs, later eliminating of conditionals or roundoff errors.
397 It is still practical to have them reported for debugging of simple
398 testcases. */
399 static void
400 check_bb_profile (basic_block bb, FILE * file, int indent, int flags)
402 edge e;
403 int sum = 0;
404 gcov_type lsum;
405 edge_iterator ei;
406 struct function *fun = DECL_STRUCT_FUNCTION (current_function_decl);
407 char *s_indent = (char *) alloca ((size_t) indent + 1);
408 memset ((void *) s_indent, ' ', (size_t) indent);
409 s_indent[indent] = '\0';
411 if (profile_status_for_fn (fun) == PROFILE_ABSENT)
412 return;
414 if (bb != EXIT_BLOCK_PTR_FOR_FN (fun))
416 FOR_EACH_EDGE (e, ei, bb->succs)
417 sum += e->probability;
418 if (EDGE_COUNT (bb->succs) && abs (sum - REG_BR_PROB_BASE) > 100)
419 fprintf (file, "%s%sInvalid sum of outgoing probabilities %.1f%%\n",
420 (flags & TDF_COMMENT) ? ";; " : "", s_indent,
421 sum * 100.0 / REG_BR_PROB_BASE);
422 lsum = 0;
423 FOR_EACH_EDGE (e, ei, bb->succs)
424 lsum += e->count;
425 if (EDGE_COUNT (bb->succs)
426 && (lsum - bb->count > 100 || lsum - bb->count < -100))
427 fprintf (file, "%s%sInvalid sum of outgoing counts %i, should be %i\n",
428 (flags & TDF_COMMENT) ? ";; " : "", s_indent,
429 (int) lsum, (int) bb->count);
431 if (bb != ENTRY_BLOCK_PTR_FOR_FN (fun))
433 sum = 0;
434 FOR_EACH_EDGE (e, ei, bb->preds)
435 sum += EDGE_FREQUENCY (e);
436 if (abs (sum - bb->frequency) > 100)
437 fprintf (file,
438 "%s%sInvalid sum of incoming frequencies %i, should be %i\n",
439 (flags & TDF_COMMENT) ? ";; " : "", s_indent,
440 sum, bb->frequency);
441 lsum = 0;
442 FOR_EACH_EDGE (e, ei, bb->preds)
443 lsum += e->count;
444 if (lsum - bb->count > 100 || lsum - bb->count < -100)
445 fprintf (file, "%s%sInvalid sum of incoming counts %i, should be %i\n",
446 (flags & TDF_COMMENT) ? ";; " : "", s_indent,
447 (int) lsum, (int) bb->count);
449 if (BB_PARTITION (bb) == BB_COLD_PARTITION)
451 /* Warn about inconsistencies in the partitioning that are
452 currently caused by profile insanities created via optimization. */
453 if (!probably_never_executed_bb_p (fun, bb))
454 fprintf (file, "%s%sBlock in cold partition with hot count\n",
455 (flags & TDF_COMMENT) ? ";; " : "", s_indent);
456 FOR_EACH_EDGE (e, ei, bb->preds)
458 if (!probably_never_executed_edge_p (fun, e))
459 fprintf (file,
460 "%s%sBlock in cold partition with incoming hot edge\n",
461 (flags & TDF_COMMENT) ? ";; " : "", s_indent);
466 void
467 dump_edge_info (FILE *file, edge e, int flags, int do_succ)
469 basic_block side = (do_succ ? e->dest : e->src);
470 bool do_details = false;
472 if ((flags & TDF_DETAILS) != 0
473 && (flags & TDF_SLIM) == 0)
474 do_details = true;
476 if (side->index == ENTRY_BLOCK)
477 fputs (" ENTRY", file);
478 else if (side->index == EXIT_BLOCK)
479 fputs (" EXIT", file);
480 else
481 fprintf (file, " %d", side->index);
483 if (e->probability && do_details)
484 fprintf (file, " [%.1f%%] ", e->probability * 100.0 / REG_BR_PROB_BASE);
486 if (e->count && do_details)
488 fputs (" count:", file);
489 fprintf (file, "%"PRId64, e->count);
492 if (e->flags && do_details)
494 static const char * const bitnames[] =
496 #define DEF_EDGE_FLAG(NAME,IDX) #NAME ,
497 #include "cfg-flags.def"
498 NULL
499 #undef DEF_EDGE_FLAG
501 bool comma = false;
502 int i, flags = e->flags;
504 gcc_assert (e->flags <= EDGE_ALL_FLAGS);
505 fputs (" (", file);
506 for (i = 0; flags; i++)
507 if (flags & (1 << i))
509 flags &= ~(1 << i);
511 if (comma)
512 fputc (',', file);
513 fputs (bitnames[i], file);
514 comma = true;
517 fputc (')', file);
521 DEBUG_FUNCTION void
522 debug (edge_def &ref)
524 /* FIXME (crowl): Is this desireable? */
525 dump_edge_info (stderr, &ref, 0, false);
526 dump_edge_info (stderr, &ref, 0, true);
529 DEBUG_FUNCTION void
530 debug (edge_def *ptr)
532 if (ptr)
533 debug (*ptr);
534 else
535 fprintf (stderr, "<nil>\n");
538 /* Simple routines to easily allocate AUX fields of basic blocks. */
540 static struct obstack block_aux_obstack;
541 static void *first_block_aux_obj = 0;
542 static struct obstack edge_aux_obstack;
543 static void *first_edge_aux_obj = 0;
545 /* Allocate a memory block of SIZE as BB->aux. The obstack must
546 be first initialized by alloc_aux_for_blocks. */
548 static void
549 alloc_aux_for_block (basic_block bb, int size)
551 /* Verify that aux field is clear. */
552 gcc_assert (!bb->aux && first_block_aux_obj);
553 bb->aux = obstack_alloc (&block_aux_obstack, size);
554 memset (bb->aux, 0, size);
557 /* Initialize the block_aux_obstack and if SIZE is nonzero, call
558 alloc_aux_for_block for each basic block. */
560 void
561 alloc_aux_for_blocks (int size)
563 static int initialized;
565 if (!initialized)
567 gcc_obstack_init (&block_aux_obstack);
568 initialized = 1;
570 else
571 /* Check whether AUX data are still allocated. */
572 gcc_assert (!first_block_aux_obj);
574 first_block_aux_obj = obstack_alloc (&block_aux_obstack, 0);
575 if (size)
577 basic_block bb;
579 FOR_ALL_BB_FN (bb, cfun)
580 alloc_aux_for_block (bb, size);
584 /* Clear AUX pointers of all blocks. */
586 void
587 clear_aux_for_blocks (void)
589 basic_block bb;
591 FOR_ALL_BB_FN (bb, cfun)
592 bb->aux = NULL;
595 /* Free data allocated in block_aux_obstack and clear AUX pointers
596 of all blocks. */
598 void
599 free_aux_for_blocks (void)
601 gcc_assert (first_block_aux_obj);
602 obstack_free (&block_aux_obstack, first_block_aux_obj);
603 first_block_aux_obj = NULL;
605 clear_aux_for_blocks ();
608 /* Allocate a memory edge of SIZE as E->aux. The obstack must
609 be first initialized by alloc_aux_for_edges. */
611 void
612 alloc_aux_for_edge (edge e, int size)
614 /* Verify that aux field is clear. */
615 gcc_assert (!e->aux && first_edge_aux_obj);
616 e->aux = obstack_alloc (&edge_aux_obstack, size);
617 memset (e->aux, 0, size);
620 /* Initialize the edge_aux_obstack and if SIZE is nonzero, call
621 alloc_aux_for_edge for each basic edge. */
623 void
624 alloc_aux_for_edges (int size)
626 static int initialized;
628 if (!initialized)
630 gcc_obstack_init (&edge_aux_obstack);
631 initialized = 1;
633 else
634 /* Check whether AUX data are still allocated. */
635 gcc_assert (!first_edge_aux_obj);
637 first_edge_aux_obj = obstack_alloc (&edge_aux_obstack, 0);
638 if (size)
640 basic_block bb;
642 FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun),
643 EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
645 edge e;
646 edge_iterator ei;
648 FOR_EACH_EDGE (e, ei, bb->succs)
649 alloc_aux_for_edge (e, size);
654 /* Clear AUX pointers of all edges. */
656 void
657 clear_aux_for_edges (void)
659 basic_block bb;
660 edge e;
662 FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun),
663 EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
665 edge_iterator ei;
666 FOR_EACH_EDGE (e, ei, bb->succs)
667 e->aux = NULL;
671 /* Free data allocated in edge_aux_obstack and clear AUX pointers
672 of all edges. */
674 void
675 free_aux_for_edges (void)
677 gcc_assert (first_edge_aux_obj);
678 obstack_free (&edge_aux_obstack, first_edge_aux_obj);
679 first_edge_aux_obj = NULL;
681 clear_aux_for_edges ();
684 DEBUG_FUNCTION void
685 debug_bb (basic_block bb)
687 dump_bb (stderr, bb, 0, dump_flags);
690 DEBUG_FUNCTION basic_block
691 debug_bb_n (int n)
693 basic_block bb = BASIC_BLOCK_FOR_FN (cfun, n);
694 debug_bb (bb);
695 return bb;
698 /* Dumps cfg related information about basic block BB to OUTF.
699 If HEADER is true, dump things that appear before the instructions
700 contained in BB. If FOOTER is true, dump things that appear after.
701 Flags are the TDF_* masks as documented in dumpfile.h.
702 NB: With TDF_DETAILS, it is assumed that cfun is available, so
703 that maybe_hot_bb_p and probably_never_executed_bb_p don't ICE. */
705 void
706 dump_bb_info (FILE *outf, basic_block bb, int indent, int flags,
707 bool do_header, bool do_footer)
709 edge_iterator ei;
710 edge e;
711 static const char * const bb_bitnames[] =
713 #define DEF_BASIC_BLOCK_FLAG(NAME,IDX) #NAME ,
714 #include "cfg-flags.def"
715 NULL
716 #undef DEF_BASIC_BLOCK_FLAG
718 const unsigned n_bitnames = sizeof (bb_bitnames) / sizeof (char *);
719 bool first;
720 char *s_indent = (char *) alloca ((size_t) indent + 1);
721 memset ((void *) s_indent, ' ', (size_t) indent);
722 s_indent[indent] = '\0';
724 gcc_assert (bb->flags <= BB_ALL_FLAGS);
726 if (do_header)
728 unsigned i;
730 if (flags & TDF_COMMENT)
731 fputs (";; ", outf);
732 fprintf (outf, "%sbasic block %d, loop depth %d",
733 s_indent, bb->index, bb_loop_depth (bb));
734 if (flags & TDF_DETAILS)
736 struct function *fun = DECL_STRUCT_FUNCTION (current_function_decl);
737 fprintf (outf, ", count " "%"PRId64,
738 (int64_t) bb->count);
739 fprintf (outf, ", freq %i", bb->frequency);
740 if (maybe_hot_bb_p (fun, bb))
741 fputs (", maybe hot", outf);
742 if (probably_never_executed_bb_p (fun, bb))
743 fputs (", probably never executed", outf);
745 fputc ('\n', outf);
747 if (flags & TDF_DETAILS)
749 check_bb_profile (bb, outf, indent, flags);
750 if (flags & TDF_COMMENT)
751 fputs (";; ", outf);
752 fprintf (outf, "%s prev block ", s_indent);
753 if (bb->prev_bb)
754 fprintf (outf, "%d", bb->prev_bb->index);
755 else
756 fprintf (outf, "(nil)");
757 fprintf (outf, ", next block ");
758 if (bb->next_bb)
759 fprintf (outf, "%d", bb->next_bb->index);
760 else
761 fprintf (outf, "(nil)");
763 fputs (", flags:", outf);
764 first = true;
765 for (i = 0; i < n_bitnames; i++)
766 if (bb->flags & (1 << i))
768 if (first)
769 fputs (" (", outf);
770 else
771 fputs (", ", outf);
772 first = false;
773 fputs (bb_bitnames[i], outf);
775 if (!first)
776 fputc (')', outf);
777 fputc ('\n', outf);
780 if (flags & TDF_COMMENT)
781 fputs (";; ", outf);
782 fprintf (outf, "%s pred: ", s_indent);
783 first = true;
784 FOR_EACH_EDGE (e, ei, bb->preds)
786 if (! first)
788 if (flags & TDF_COMMENT)
789 fputs (";; ", outf);
790 fprintf (outf, "%s ", s_indent);
792 first = false;
793 dump_edge_info (outf, e, flags, 0);
794 fputc ('\n', outf);
796 if (first)
797 fputc ('\n', outf);
800 if (do_footer)
802 if (flags & TDF_COMMENT)
803 fputs (";; ", outf);
804 fprintf (outf, "%s succ: ", s_indent);
805 first = true;
806 FOR_EACH_EDGE (e, ei, bb->succs)
808 if (! first)
810 if (flags & TDF_COMMENT)
811 fputs (";; ", outf);
812 fprintf (outf, "%s ", s_indent);
814 first = false;
815 dump_edge_info (outf, e, flags, 1);
816 fputc ('\n', outf);
818 if (first)
819 fputc ('\n', outf);
823 /* Dumps a brief description of cfg to FILE. */
825 void
826 brief_dump_cfg (FILE *file, int flags)
828 basic_block bb;
830 FOR_EACH_BB_FN (bb, cfun)
832 dump_bb_info (file, bb, 0,
833 flags & (TDF_COMMENT | TDF_DETAILS),
834 true, true);
838 /* An edge originally destinating BB of FREQUENCY and COUNT has been proved to
839 leave the block by TAKEN_EDGE. Update profile of BB such that edge E can be
840 redirected to destination of TAKEN_EDGE.
842 This function may leave the profile inconsistent in the case TAKEN_EDGE
843 frequency or count is believed to be lower than FREQUENCY or COUNT
844 respectively. */
845 void
846 update_bb_profile_for_threading (basic_block bb, int edge_frequency,
847 gcov_type count, edge taken_edge)
849 edge c;
850 int prob;
851 edge_iterator ei;
853 bb->count -= count;
854 if (bb->count < 0)
856 if (dump_file)
857 fprintf (dump_file, "bb %i count became negative after threading",
858 bb->index);
859 bb->count = 0;
862 /* Compute the probability of TAKEN_EDGE being reached via threaded edge.
863 Watch for overflows. */
864 if (bb->frequency)
865 prob = GCOV_COMPUTE_SCALE (edge_frequency, bb->frequency);
866 else
867 prob = 0;
868 if (prob > taken_edge->probability)
870 if (dump_file)
871 fprintf (dump_file, "Jump threading proved probability of edge "
872 "%i->%i too small (it is %i, should be %i).\n",
873 taken_edge->src->index, taken_edge->dest->index,
874 taken_edge->probability, prob);
875 prob = taken_edge->probability;
878 /* Now rescale the probabilities. */
879 taken_edge->probability -= prob;
880 prob = REG_BR_PROB_BASE - prob;
881 bb->frequency -= edge_frequency;
882 if (bb->frequency < 0)
883 bb->frequency = 0;
884 if (prob <= 0)
886 if (dump_file)
887 fprintf (dump_file, "Edge frequencies of bb %i has been reset, "
888 "frequency of block should end up being 0, it is %i\n",
889 bb->index, bb->frequency);
890 EDGE_SUCC (bb, 0)->probability = REG_BR_PROB_BASE;
891 ei = ei_start (bb->succs);
892 ei_next (&ei);
893 for (; (c = ei_safe_edge (ei)); ei_next (&ei))
894 c->probability = 0;
896 else if (prob != REG_BR_PROB_BASE)
898 int scale = RDIV (65536 * REG_BR_PROB_BASE, prob);
900 FOR_EACH_EDGE (c, ei, bb->succs)
902 /* Protect from overflow due to additional scaling. */
903 if (c->probability > prob)
904 c->probability = REG_BR_PROB_BASE;
905 else
907 c->probability = RDIV (c->probability * scale, 65536);
908 if (c->probability > REG_BR_PROB_BASE)
909 c->probability = REG_BR_PROB_BASE;
914 gcc_assert (bb == taken_edge->src);
915 taken_edge->count -= count;
916 if (taken_edge->count < 0)
918 if (dump_file)
919 fprintf (dump_file, "edge %i->%i count became negative after threading",
920 taken_edge->src->index, taken_edge->dest->index);
921 taken_edge->count = 0;
925 /* Multiply all frequencies of basic blocks in array BBS of length NBBS
926 by NUM/DEN, in int arithmetic. May lose some accuracy. */
927 void
928 scale_bbs_frequencies_int (basic_block *bbs, int nbbs, int num, int den)
930 int i;
931 edge e;
932 if (num < 0)
933 num = 0;
935 /* Scale NUM and DEN to avoid overflows. Frequencies are in order of
936 10^4, if we make DEN <= 10^3, we can afford to upscale by 100
937 and still safely fit in int during calculations. */
938 if (den > 1000)
940 if (num > 1000000)
941 return;
943 num = RDIV (1000 * num, den);
944 den = 1000;
946 if (num > 100 * den)
947 return;
949 for (i = 0; i < nbbs; i++)
951 edge_iterator ei;
952 bbs[i]->frequency = RDIV (bbs[i]->frequency * num, den);
953 /* Make sure the frequencies do not grow over BB_FREQ_MAX. */
954 if (bbs[i]->frequency > BB_FREQ_MAX)
955 bbs[i]->frequency = BB_FREQ_MAX;
956 bbs[i]->count = RDIV (bbs[i]->count * num, den);
957 FOR_EACH_EDGE (e, ei, bbs[i]->succs)
958 e->count = RDIV (e->count * num, den);
962 /* numbers smaller than this value are safe to multiply without getting
963 64bit overflow. */
964 #define MAX_SAFE_MULTIPLIER (1 << (sizeof (int64_t) * 4 - 1))
966 /* Multiply all frequencies of basic blocks in array BBS of length NBBS
967 by NUM/DEN, in gcov_type arithmetic. More accurate than previous
968 function but considerably slower. */
969 void
970 scale_bbs_frequencies_gcov_type (basic_block *bbs, int nbbs, gcov_type num,
971 gcov_type den)
973 int i;
974 edge e;
975 gcov_type fraction = RDIV (num * 65536, den);
977 gcc_assert (fraction >= 0);
979 if (num < MAX_SAFE_MULTIPLIER)
980 for (i = 0; i < nbbs; i++)
982 edge_iterator ei;
983 bbs[i]->frequency = RDIV (bbs[i]->frequency * num, den);
984 if (bbs[i]->count <= MAX_SAFE_MULTIPLIER)
985 bbs[i]->count = RDIV (bbs[i]->count * num, den);
986 else
987 bbs[i]->count = RDIV (bbs[i]->count * fraction, 65536);
988 FOR_EACH_EDGE (e, ei, bbs[i]->succs)
989 if (bbs[i]->count <= MAX_SAFE_MULTIPLIER)
990 e->count = RDIV (e->count * num, den);
991 else
992 e->count = RDIV (e->count * fraction, 65536);
994 else
995 for (i = 0; i < nbbs; i++)
997 edge_iterator ei;
998 if (sizeof (gcov_type) > sizeof (int))
999 bbs[i]->frequency = RDIV (bbs[i]->frequency * num, den);
1000 else
1001 bbs[i]->frequency = RDIV (bbs[i]->frequency * fraction, 65536);
1002 bbs[i]->count = RDIV (bbs[i]->count * fraction, 65536);
1003 FOR_EACH_EDGE (e, ei, bbs[i]->succs)
1004 e->count = RDIV (e->count * fraction, 65536);
1008 /* Helper types for hash tables. */
1010 struct htab_bb_copy_original_entry
1012 /* Block we are attaching info to. */
1013 int index1;
1014 /* Index of original or copy (depending on the hashtable) */
1015 int index2;
1018 struct bb_copy_hasher : typed_noop_remove <htab_bb_copy_original_entry>
1020 typedef htab_bb_copy_original_entry value_type;
1021 typedef htab_bb_copy_original_entry compare_type;
1022 static inline hashval_t hash (const value_type *);
1023 static inline bool equal (const value_type *existing,
1024 const compare_type * candidate);
1027 inline hashval_t
1028 bb_copy_hasher::hash (const value_type *data)
1030 return data->index1;
1033 inline bool
1034 bb_copy_hasher::equal (const value_type *data, const compare_type *data2)
1036 return data->index1 == data2->index1;
1039 /* Data structures used to maintain mapping between basic blocks and
1040 copies. */
1041 static hash_table<bb_copy_hasher> *bb_original;
1042 static hash_table<bb_copy_hasher> *bb_copy;
1044 /* And between loops and copies. */
1045 static hash_table<bb_copy_hasher> *loop_copy;
1046 static alloc_pool original_copy_bb_pool;
1049 /* Initialize the data structures to maintain mapping between blocks
1050 and its copies. */
1051 void
1052 initialize_original_copy_tables (void)
1054 gcc_assert (!original_copy_bb_pool);
1055 original_copy_bb_pool
1056 = create_alloc_pool ("original_copy",
1057 sizeof (struct htab_bb_copy_original_entry), 10);
1058 bb_original = new hash_table<bb_copy_hasher> (10);
1059 bb_copy = new hash_table<bb_copy_hasher> (10);
1060 loop_copy = new hash_table<bb_copy_hasher> (10);
1063 /* Free the data structures to maintain mapping between blocks and
1064 its copies. */
1065 void
1066 free_original_copy_tables (void)
1068 gcc_assert (original_copy_bb_pool);
1069 delete bb_copy;
1070 bb_copy = NULL;
1071 delete bb_original;
1072 bb_copy = NULL;
1073 delete loop_copy;
1074 loop_copy = NULL;
1075 free_alloc_pool (original_copy_bb_pool);
1076 original_copy_bb_pool = NULL;
1079 /* Removes the value associated with OBJ from table TAB. */
1081 static void
1082 copy_original_table_clear (hash_table<bb_copy_hasher> *tab, unsigned obj)
1084 htab_bb_copy_original_entry **slot;
1085 struct htab_bb_copy_original_entry key, *elt;
1087 if (!original_copy_bb_pool)
1088 return;
1090 key.index1 = obj;
1091 slot = tab->find_slot (&key, NO_INSERT);
1092 if (!slot)
1093 return;
1095 elt = *slot;
1096 tab->clear_slot (slot);
1097 pool_free (original_copy_bb_pool, elt);
1100 /* Sets the value associated with OBJ in table TAB to VAL.
1101 Do nothing when data structures are not initialized. */
1103 static void
1104 copy_original_table_set (hash_table<bb_copy_hasher> *tab,
1105 unsigned obj, unsigned val)
1107 struct htab_bb_copy_original_entry **slot;
1108 struct htab_bb_copy_original_entry key;
1110 if (!original_copy_bb_pool)
1111 return;
1113 key.index1 = obj;
1114 slot = tab->find_slot (&key, INSERT);
1115 if (!*slot)
1117 *slot = (struct htab_bb_copy_original_entry *)
1118 pool_alloc (original_copy_bb_pool);
1119 (*slot)->index1 = obj;
1121 (*slot)->index2 = val;
1124 /* Set original for basic block. Do nothing when data structures are not
1125 initialized so passes not needing this don't need to care. */
1126 void
1127 set_bb_original (basic_block bb, basic_block original)
1129 copy_original_table_set (bb_original, bb->index, original->index);
1132 /* Get the original basic block. */
1133 basic_block
1134 get_bb_original (basic_block bb)
1136 struct htab_bb_copy_original_entry *entry;
1137 struct htab_bb_copy_original_entry key;
1139 gcc_assert (original_copy_bb_pool);
1141 key.index1 = bb->index;
1142 entry = bb_original->find (&key);
1143 if (entry)
1144 return BASIC_BLOCK_FOR_FN (cfun, entry->index2);
1145 else
1146 return NULL;
1149 /* Set copy for basic block. Do nothing when data structures are not
1150 initialized so passes not needing this don't need to care. */
1151 void
1152 set_bb_copy (basic_block bb, basic_block copy)
1154 copy_original_table_set (bb_copy, bb->index, copy->index);
1157 /* Get the copy of basic block. */
1158 basic_block
1159 get_bb_copy (basic_block bb)
1161 struct htab_bb_copy_original_entry *entry;
1162 struct htab_bb_copy_original_entry key;
1164 gcc_assert (original_copy_bb_pool);
1166 key.index1 = bb->index;
1167 entry = bb_copy->find (&key);
1168 if (entry)
1169 return BASIC_BLOCK_FOR_FN (cfun, entry->index2);
1170 else
1171 return NULL;
1174 /* Set copy for LOOP to COPY. Do nothing when data structures are not
1175 initialized so passes not needing this don't need to care. */
1177 void
1178 set_loop_copy (struct loop *loop, struct loop *copy)
1180 if (!copy)
1181 copy_original_table_clear (loop_copy, loop->num);
1182 else
1183 copy_original_table_set (loop_copy, loop->num, copy->num);
1186 /* Get the copy of LOOP. */
1188 struct loop *
1189 get_loop_copy (struct loop *loop)
1191 struct htab_bb_copy_original_entry *entry;
1192 struct htab_bb_copy_original_entry key;
1194 gcc_assert (original_copy_bb_pool);
1196 key.index1 = loop->num;
1197 entry = loop_copy->find (&key);
1198 if (entry)
1199 return get_loop (cfun, entry->index2);
1200 else
1201 return NULL;