1 /* Hooks for cfg representation specific functions.
2 Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
3 Contributed by Sebastian Pop <s.pop@laposte.net>
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to
19 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
20 Boston, MA 02110-1301, USA. */
24 #include "coretypes.h"
28 #include "basic-block.h"
29 #include "tree-flow.h"
34 /* A pointer to one of the hooks containers. */
35 static struct cfg_hooks *cfg_hooks;
37 /* Initialization of functions specific to the rtl IR. */
39 rtl_register_cfg_hooks (void)
41 cfg_hooks = &rtl_cfg_hooks;
44 /* Initialization of functions specific to the rtl IR. */
46 cfg_layout_rtl_register_cfg_hooks (void)
48 cfg_hooks = &cfg_layout_rtl_cfg_hooks;
51 /* Initialization of functions specific to the tree IR. */
54 tree_register_cfg_hooks (void)
56 cfg_hooks = &tree_cfg_hooks;
59 /* Returns current ir type. */
62 current_ir_type (void)
64 if (cfg_hooks == &tree_cfg_hooks)
66 else if (cfg_hooks == &rtl_cfg_hooks)
68 else if (cfg_hooks == &cfg_layout_rtl_cfg_hooks)
69 return IR_RTL_CFGLAYOUT;
74 /* Verify the CFG consistency.
76 Currently it does following: checks edge and basic block list correctness
77 and calls into IL dependent checking then. */
80 verify_flow_info (void)
82 size_t *edge_checksum;
84 basic_block bb, last_bb_seen;
85 basic_block *last_visited;
87 timevar_push (TV_CFG_VERIFY);
88 last_visited = XCNEWVEC (basic_block, last_basic_block);
89 edge_checksum = XCNEWVEC (size_t, last_basic_block);
91 /* Check bb chain & numbers. */
92 last_bb_seen = ENTRY_BLOCK_PTR;
93 FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR->next_bb, NULL, next_bb)
95 if (bb != EXIT_BLOCK_PTR
96 && bb != BASIC_BLOCK (bb->index))
98 error ("bb %d on wrong place", bb->index);
102 if (bb->prev_bb != last_bb_seen)
104 error ("prev_bb of %d should be %d, not %d",
105 bb->index, last_bb_seen->index, bb->prev_bb->index);
112 /* Now check the basic blocks (boundaries etc.) */
113 FOR_EACH_BB_REVERSE (bb)
119 if (bb->loop_father != NULL && current_loops == NULL)
121 error ("verify_flow_info: Block %i has loop_father, but there are no loops",
125 if (bb->loop_father == NULL && current_loops != NULL)
127 error ("verify_flow_info: Block %i lacks loop_father", bb->index);
133 error ("verify_flow_info: Wrong count of block %i %i",
134 bb->index, (int)bb->count);
137 if (bb->frequency < 0)
139 error ("verify_flow_info: Wrong frequency of block %i %i",
140 bb->index, bb->frequency);
143 FOR_EACH_EDGE (e, ei, bb->succs)
145 if (last_visited [e->dest->index] == bb)
147 error ("verify_flow_info: Duplicate edge %i->%i",
148 e->src->index, e->dest->index);
151 if (e->probability < 0 || e->probability > REG_BR_PROB_BASE)
153 error ("verify_flow_info: Wrong probability of edge %i->%i %i",
154 e->src->index, e->dest->index, e->probability);
159 error ("verify_flow_info: Wrong count of edge %i->%i %i",
160 e->src->index, e->dest->index, (int)e->count);
164 last_visited [e->dest->index] = bb;
166 if (e->flags & EDGE_FALLTHRU)
171 error ("verify_flow_info: Basic block %d succ edge is corrupted",
173 fprintf (stderr, "Predecessor: ");
174 dump_edge_info (stderr, e, 0);
175 fprintf (stderr, "\nSuccessor: ");
176 dump_edge_info (stderr, e, 1);
177 fprintf (stderr, "\n");
181 edge_checksum[e->dest->index] += (size_t) e;
185 error ("wrong amount of branch edges after unconditional jump %i", bb->index);
189 FOR_EACH_EDGE (e, ei, bb->preds)
193 error ("basic block %d pred edge is corrupted", bb->index);
194 fputs ("Predecessor: ", stderr);
195 dump_edge_info (stderr, e, 0);
196 fputs ("\nSuccessor: ", stderr);
197 dump_edge_info (stderr, e, 1);
198 fputc ('\n', stderr);
202 if (ei.index != e->dest_idx)
204 error ("basic block %d pred edge is corrupted", bb->index);
205 error ("its dest_idx should be %d, not %d",
206 ei.index, e->dest_idx);
207 fputs ("Predecessor: ", stderr);
208 dump_edge_info (stderr, e, 0);
209 fputs ("\nSuccessor: ", stderr);
210 dump_edge_info (stderr, e, 1);
211 fputc ('\n', stderr);
215 edge_checksum[e->dest->index] -= (size_t) e;
219 /* Complete edge checksumming for ENTRY and EXIT. */
224 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
225 edge_checksum[e->dest->index] += (size_t) e;
227 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
228 edge_checksum[e->dest->index] -= (size_t) e;
231 FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
232 if (edge_checksum[bb->index])
234 error ("basic block %i edge lists are corrupted", bb->index);
238 last_bb_seen = ENTRY_BLOCK_PTR;
242 free (edge_checksum);
244 if (cfg_hooks->verify_flow_info)
245 err |= cfg_hooks->verify_flow_info ();
247 internal_error ("verify_flow_info failed");
248 timevar_pop (TV_CFG_VERIFY);
251 /* Print out one basic block. This function takes care of the purely
252 graph related information. The cfg hook for the active representation
253 should dump representation-specific information. */
256 dump_bb (basic_block bb, FILE *outf, int indent)
262 s_indent = alloca ((size_t) indent + 1);
263 memset (s_indent, ' ', (size_t) indent);
264 s_indent[indent] = '\0';
266 fprintf (outf, ";;%s basic block %d, loop depth %d, count ",
267 s_indent, bb->index, bb->loop_depth);
268 fprintf (outf, HOST_WIDEST_INT_PRINT_DEC, (HOST_WIDEST_INT) bb->count);
271 fprintf (outf, ";;%s prev block ", s_indent);
273 fprintf (outf, "%d, ", bb->prev_bb->index);
275 fprintf (outf, "(nil), ");
276 fprintf (outf, "next block ");
278 fprintf (outf, "%d", bb->next_bb->index);
280 fprintf (outf, "(nil)");
283 fprintf (outf, ";;%s pred: ", s_indent);
284 FOR_EACH_EDGE (e, ei, bb->preds)
285 dump_edge_info (outf, e, 0);
288 fprintf (outf, ";;%s succ: ", s_indent);
289 FOR_EACH_EDGE (e, ei, bb->succs)
290 dump_edge_info (outf, e, 1);
293 if (cfg_hooks->dump_bb)
294 cfg_hooks->dump_bb (bb, outf, indent);
297 /* Redirect edge E to the given basic block DEST and update underlying program
298 representation. Returns edge representing redirected branch (that may not
299 be equivalent to E in the case of duplicate edges being removed) or NULL
300 if edge is not easily redirectable for whatever reason. */
303 redirect_edge_and_branch (edge e, basic_block dest)
307 if (!cfg_hooks->redirect_edge_and_branch)
308 internal_error ("%s does not support redirect_edge_and_branch",
311 ret = cfg_hooks->redirect_edge_and_branch (e, dest);
313 /* If RET != E, then the edge E was removed since RET already lead to the
315 if (ret != NULL && current_loops != NULL)
316 rescan_loop_exit (e, false, ret != e);
321 /* Returns true if it is possible to remove the edge E by redirecting it
322 to the destination of the other edge going from its source. */
325 can_remove_branch_p (edge e)
327 if (!cfg_hooks->can_remove_branch_p)
328 internal_error ("%s does not support can_remove_branch_p",
331 if (EDGE_COUNT (e->src->succs) != 2)
334 return cfg_hooks->can_remove_branch_p (e);
337 /* Removes E, by redirecting it to the destination of the other edge going
338 from its source. Can_remove_branch_p must be true for E, hence this
339 operation cannot fail. */
342 remove_branch (edge e)
345 basic_block src = e->src;
348 gcc_assert (EDGE_COUNT (e->src->succs) == 2);
350 other = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e);
351 irr = other->flags & EDGE_IRREDUCIBLE_LOOP;
353 if (current_loops != NULL)
354 rescan_loop_exit (e, false, true);
356 e = redirect_edge_and_branch (e, other->dest);
357 gcc_assert (e != NULL);
359 e->flags &= ~EDGE_IRREDUCIBLE_LOOP;
363 /* Redirect the edge E to basic block DEST even if it requires creating
364 of a new basic block; then it returns the newly created basic block.
365 Aborts when redirection is impossible. */
368 redirect_edge_and_branch_force (edge e, basic_block dest)
370 basic_block ret, src = e->src;
373 if (!cfg_hooks->redirect_edge_and_branch_force)
374 internal_error ("%s does not support redirect_edge_and_branch_force",
377 if (current_loops != NULL)
378 rescan_loop_exit (e, false, true);
380 ret = cfg_hooks->redirect_edge_and_branch_force (e, dest);
381 if (current_loops != NULL)
385 loop = find_common_loop (single_pred (ret)->loop_father,
386 single_succ (ret)->loop_father);
387 add_bb_to_loop (ret, loop);
389 else if (find_edge (src, dest) == e)
390 rescan_loop_exit (e, true, false);
396 /* Splits basic block BB after the specified instruction I (but at least after
397 the labels). If I is NULL, splits just after labels. The newly created edge
398 is returned. The new basic block is created just after the old one. */
401 split_block (basic_block bb, void *i)
405 if (!cfg_hooks->split_block)
406 internal_error ("%s does not support split_block", cfg_hooks->name);
408 new_bb = cfg_hooks->split_block (bb, i);
412 new_bb->count = bb->count;
413 new_bb->frequency = bb->frequency;
414 new_bb->loop_depth = bb->loop_depth;
416 if (dom_info_available_p (CDI_DOMINATORS))
418 redirect_immediate_dominators (CDI_DOMINATORS, bb, new_bb);
419 set_immediate_dominator (CDI_DOMINATORS, new_bb, bb);
422 if (current_loops != NULL)
423 add_bb_to_loop (new_bb, bb->loop_father);
425 return make_single_succ_edge (bb, new_bb, EDGE_FALLTHRU);
428 /* Splits block BB just after labels. The newly created edge is returned. */
431 split_block_after_labels (basic_block bb)
433 return split_block (bb, NULL);
436 /* Moves block BB immediately after block AFTER. Returns false if the
437 movement was impossible. */
440 move_block_after (basic_block bb, basic_block after)
444 if (!cfg_hooks->move_block_after)
445 internal_error ("%s does not support move_block_after", cfg_hooks->name);
447 ret = cfg_hooks->move_block_after (bb, after);
452 /* Deletes the basic block BB. */
455 delete_basic_block (basic_block bb)
457 if (!cfg_hooks->delete_basic_block)
458 internal_error ("%s does not support delete_basic_block", cfg_hooks->name);
460 cfg_hooks->delete_basic_block (bb);
462 if (current_loops != NULL)
464 struct loop *loop = bb->loop_father;
466 /* If we remove the header or the latch of a loop, mark the loop for
467 removal by setting its header and latch to NULL. */
468 if (loop->latch == bb
469 || loop->header == bb)
475 remove_bb_from_loops (bb);
478 /* Remove the edges into and out of this block. Note that there may
479 indeed be edges in, if we are removing an unreachable loop. */
480 while (EDGE_COUNT (bb->preds) != 0)
481 remove_edge (EDGE_PRED (bb, 0));
482 while (EDGE_COUNT (bb->succs) != 0)
483 remove_edge (EDGE_SUCC (bb, 0));
485 if (dom_computed[CDI_DOMINATORS])
486 delete_from_dominance_info (CDI_DOMINATORS, bb);
487 if (dom_computed[CDI_POST_DOMINATORS])
488 delete_from_dominance_info (CDI_POST_DOMINATORS, bb);
490 /* Remove the basic block from the array. */
494 /* Splits edge E and returns the newly created basic block. */
500 gcov_type count = e->count;
501 int freq = EDGE_FREQUENCY (e);
503 bool irr = (e->flags & EDGE_IRREDUCIBLE_LOOP) != 0;
505 basic_block src = e->src, dest = e->dest;
507 if (!cfg_hooks->split_edge)
508 internal_error ("%s does not support split_edge", cfg_hooks->name);
510 if (current_loops != NULL)
511 rescan_loop_exit (e, false, true);
513 ret = cfg_hooks->split_edge (e);
515 ret->frequency = freq;
516 single_succ_edge (ret)->probability = REG_BR_PROB_BASE;
517 single_succ_edge (ret)->count = count;
521 ret->flags |= BB_IRREDUCIBLE_LOOP;
522 single_pred_edge (ret)->flags |= EDGE_IRREDUCIBLE_LOOP;
523 single_succ_edge (ret)->flags |= EDGE_IRREDUCIBLE_LOOP;
526 if (dom_computed[CDI_DOMINATORS])
527 set_immediate_dominator (CDI_DOMINATORS, ret, single_pred (ret));
529 if (dom_computed[CDI_DOMINATORS] >= DOM_NO_FAST_QUERY)
531 /* There are two cases:
533 If the immediate dominator of e->dest is not e->src, it
536 If immediate dominator of e->dest is e->src, it may become
537 ret, provided that all other predecessors of e->dest are
538 dominated by e->dest. */
540 if (get_immediate_dominator (CDI_DOMINATORS, single_succ (ret))
541 == single_pred (ret))
544 FOR_EACH_EDGE (f, ei, single_succ (ret)->preds)
546 if (f == single_succ_edge (ret))
549 if (!dominated_by_p (CDI_DOMINATORS, f->src,
555 set_immediate_dominator (CDI_DOMINATORS, single_succ (ret), ret);
559 if (current_loops != NULL)
561 loop = find_common_loop (src->loop_father, dest->loop_father);
562 add_bb_to_loop (ret, loop);
564 if (loop->latch == src)
571 /* Creates a new basic block just after the basic block AFTER.
572 HEAD and END are the first and the last statement belonging
573 to the block. If both are NULL, an empty block is created. */
576 create_basic_block (void *head, void *end, basic_block after)
580 if (!cfg_hooks->create_basic_block)
581 internal_error ("%s does not support create_basic_block", cfg_hooks->name);
583 ret = cfg_hooks->create_basic_block (head, end, after);
585 if (dom_computed[CDI_DOMINATORS])
586 add_to_dominance_info (CDI_DOMINATORS, ret);
587 if (dom_computed[CDI_POST_DOMINATORS])
588 add_to_dominance_info (CDI_POST_DOMINATORS, ret);
593 /* Creates an empty basic block just after basic block AFTER. */
596 create_empty_bb (basic_block after)
598 return create_basic_block (NULL, NULL, after);
601 /* Checks whether we may merge blocks BB1 and BB2. */
604 can_merge_blocks_p (basic_block bb1, basic_block bb2)
608 if (!cfg_hooks->can_merge_blocks_p)
609 internal_error ("%s does not support can_merge_blocks_p", cfg_hooks->name);
611 ret = cfg_hooks->can_merge_blocks_p (bb1, bb2);
617 predict_edge (edge e, enum br_predictor predictor, int probability)
619 if (!cfg_hooks->predict_edge)
620 internal_error ("%s does not support predict_edge", cfg_hooks->name);
622 cfg_hooks->predict_edge (e, predictor, probability);
626 predicted_by_p (basic_block bb, enum br_predictor predictor)
628 if (!cfg_hooks->predict_edge)
629 internal_error ("%s does not support predicted_by_p", cfg_hooks->name);
631 return cfg_hooks->predicted_by_p (bb, predictor);
634 /* Merges basic block B into basic block A. */
637 merge_blocks (basic_block a, basic_block b)
642 if (!cfg_hooks->merge_blocks)
643 internal_error ("%s does not support merge_blocks", cfg_hooks->name);
645 if (current_loops != NULL)
646 remove_bb_from_loops (b);
648 cfg_hooks->merge_blocks (a, b);
650 /* Normally there should only be one successor of A and that is B, but
651 partway though the merge of blocks for conditional_execution we'll
652 be merging a TEST block with THEN and ELSE successors. Free the
653 whole lot of them and hope the caller knows what they're doing. */
655 while (EDGE_COUNT (a->succs) != 0)
657 if (current_loops != NULL)
658 rescan_loop_exit (EDGE_SUCC (a, 0), false, true);
659 remove_edge (EDGE_SUCC (a, 0));
662 /* Adjust the edges out of B for the new owner. */
663 FOR_EACH_EDGE (e, ei, b->succs)
666 if (current_loops != NULL)
667 rescan_loop_exit (e, true, false);
670 a->flags |= b->flags;
672 /* B hasn't quite yet ceased to exist. Attempt to prevent mishap. */
673 b->preds = b->succs = NULL;
675 if (dom_computed[CDI_DOMINATORS])
676 redirect_immediate_dominators (CDI_DOMINATORS, b, a);
678 if (dom_computed[CDI_DOMINATORS])
679 delete_from_dominance_info (CDI_DOMINATORS, b);
680 if (dom_computed[CDI_POST_DOMINATORS])
681 delete_from_dominance_info (CDI_POST_DOMINATORS, b);
686 /* Split BB into entry part and the rest (the rest is the newly created block).
687 Redirect those edges for that REDIRECT_EDGE_P returns true to the entry
688 part. Returns the edge connecting the entry part to the rest. */
691 make_forwarder_block (basic_block bb, bool (*redirect_edge_p) (edge),
692 void (*new_bb_cbk) (basic_block))
696 basic_block dummy, jump;
697 struct loop *loop, *ploop, *cloop;
699 if (!cfg_hooks->make_forwarder_block)
700 internal_error ("%s does not support make_forwarder_block",
703 fallthru = split_block_after_labels (bb);
704 dummy = fallthru->src;
707 /* Redirect back edges we want to keep. */
708 for (ei = ei_start (dummy->preds); (e = ei_safe_edge (ei)); )
710 if (redirect_edge_p (e))
716 dummy->frequency -= EDGE_FREQUENCY (e);
717 dummy->count -= e->count;
718 if (dummy->frequency < 0)
719 dummy->frequency = 0;
720 if (dummy->count < 0)
722 fallthru->count -= e->count;
723 if (fallthru->count < 0)
726 jump = redirect_edge_and_branch_force (e, bb);
731 if (dom_info_available_p (CDI_DOMINATORS))
733 basic_block doms_to_fix[2];
735 doms_to_fix[0] = dummy;
737 iterate_fix_dominators (CDI_DOMINATORS, doms_to_fix, 2);
740 if (current_loops != NULL)
742 /* If we do not split a loop header, then both blocks belong to the
743 same loop. In case we split loop header and do not redirect the
744 latch edge to DUMMY, then DUMMY belongs to the outer loop, and
745 BB becomes the new header. */
746 loop = dummy->loop_father;
747 if (loop->header == dummy
748 && find_edge (loop->latch, dummy) == NULL)
750 remove_bb_from_loops (dummy);
754 FOR_EACH_EDGE (e, ei, dummy->preds)
756 cloop = find_common_loop (cloop, e->src->loop_father);
758 add_bb_to_loop (dummy, cloop);
761 /* In case we split loop latch, update it. */
762 for (ploop = loop; ploop; ploop = ploop->outer)
763 if (ploop->latch == dummy)
767 cfg_hooks->make_forwarder_block (fallthru);
773 tidy_fallthru_edge (edge e)
775 if (cfg_hooks->tidy_fallthru_edge)
776 cfg_hooks->tidy_fallthru_edge (e);
779 /* Fix up edges that now fall through, or rather should now fall through
780 but previously required a jump around now deleted blocks. Simplify
781 the search by only examining blocks numerically adjacent, since this
782 is how find_basic_blocks created them. */
785 tidy_fallthru_edges (void)
789 if (!cfg_hooks->tidy_fallthru_edge)
792 if (ENTRY_BLOCK_PTR->next_bb == EXIT_BLOCK_PTR)
795 FOR_BB_BETWEEN (b, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR->prev_bb, next_bb)
801 /* We care about simple conditional or unconditional jumps with
804 If we had a conditional branch to the next instruction when
805 find_basic_blocks was called, then there will only be one
806 out edge for the block which ended with the conditional
807 branch (since we do not create duplicate edges).
809 Furthermore, the edge will be marked as a fallthru because we
810 merge the flags for the duplicate edges. So we do not want to
811 check that the edge is not a FALLTHRU edge. */
813 if (single_succ_p (b))
815 s = single_succ_edge (b);
816 if (! (s->flags & EDGE_COMPLEX)
818 && !find_reg_note (BB_END (b), REG_CROSSING_JUMP, NULL_RTX))
819 tidy_fallthru_edge (s);
824 /* Returns true if we can duplicate basic block BB. */
827 can_duplicate_block_p (basic_block bb)
831 if (!cfg_hooks->can_duplicate_block_p)
832 internal_error ("%s does not support can_duplicate_block_p",
835 if (bb == EXIT_BLOCK_PTR || bb == ENTRY_BLOCK_PTR)
838 /* Duplicating fallthru block to exit would require adding a jump
839 and splitting the real last BB. */
840 e = find_edge (bb, EXIT_BLOCK_PTR);
841 if (e && (e->flags & EDGE_FALLTHRU))
844 return cfg_hooks->can_duplicate_block_p (bb);
847 /* Duplicates basic block BB and redirects edge E to it. Returns the
848 new basic block. The new basic block is placed after the basic block
852 duplicate_block (basic_block bb, edge e, basic_block after)
856 gcov_type new_count = e ? e->count : 0;
859 if (!cfg_hooks->duplicate_block)
860 internal_error ("%s does not support duplicate_block",
863 if (bb->count < new_count)
864 new_count = bb->count;
866 #ifdef ENABLE_CHECKING
867 gcc_assert (can_duplicate_block_p (bb));
870 new_bb = cfg_hooks->duplicate_block (bb);
872 move_block_after (new_bb, after);
874 new_bb->loop_depth = bb->loop_depth;
875 new_bb->flags = bb->flags;
876 FOR_EACH_EDGE (s, ei, bb->succs)
878 /* Since we are creating edges from a new block to successors
879 of another block (which therefore are known to be disjoint), there
880 is no need to actually check for duplicated edges. */
881 n = unchecked_make_edge (new_bb, s->dest, s->flags);
882 n->probability = s->probability;
885 /* Take care for overflows! */
886 n->count = s->count * (new_count * 10000 / bb->count) / 10000;
887 s->count -= n->count;
896 new_bb->count = new_count;
897 bb->count -= new_count;
899 new_bb->frequency = EDGE_FREQUENCY (e);
900 bb->frequency -= EDGE_FREQUENCY (e);
902 redirect_edge_and_branch_force (e, new_bb);
906 if (bb->frequency < 0)
911 new_bb->count = bb->count;
912 new_bb->frequency = bb->frequency;
915 set_bb_original (new_bb, bb);
916 set_bb_copy (bb, new_bb);
918 /* Add the new block to the prescribed loop. */
919 if (current_loops != NULL)
920 add_bb_to_loop (new_bb, bb->loop_father->copy);
925 /* Return 1 if BB ends with a call, possibly followed by some
926 instructions that must stay with the call, 0 otherwise. */
929 block_ends_with_call_p (basic_block bb)
931 if (!cfg_hooks->block_ends_with_call_p)
932 internal_error ("%s does not support block_ends_with_call_p", cfg_hooks->name);
934 return (cfg_hooks->block_ends_with_call_p) (bb);
937 /* Return 1 if BB ends with a conditional branch, 0 otherwise. */
940 block_ends_with_condjump_p (basic_block bb)
942 if (!cfg_hooks->block_ends_with_condjump_p)
943 internal_error ("%s does not support block_ends_with_condjump_p",
946 return (cfg_hooks->block_ends_with_condjump_p) (bb);
949 /* Add fake edges to the function exit for any non constant and non noreturn
950 calls, volatile inline assembly in the bitmap of blocks specified by
951 BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks
954 The goal is to expose cases in which entering a basic block does not imply
955 that all subsequent instructions must be executed. */
958 flow_call_edges_add (sbitmap blocks)
960 if (!cfg_hooks->flow_call_edges_add)
961 internal_error ("%s does not support flow_call_edges_add",
964 return (cfg_hooks->flow_call_edges_add) (blocks);
967 /* This function is called immediately after edge E is added to the
968 edge vector E->dest->preds. */
971 execute_on_growing_pred (edge e)
973 if (cfg_hooks->execute_on_growing_pred)
974 cfg_hooks->execute_on_growing_pred (e);
977 /* This function is called immediately before edge E is removed from
978 the edge vector E->dest->preds. */
981 execute_on_shrinking_pred (edge e)
983 if (cfg_hooks->execute_on_shrinking_pred)
984 cfg_hooks->execute_on_shrinking_pred (e);
987 /* This is used inside loop versioning when we want to insert
988 stmts/insns on the edges, which have a different behavior
989 in tree's and in RTL, so we made a CFG hook. */
991 lv_flush_pending_stmts (edge e)
993 if (cfg_hooks->flush_pending_stmts)
994 cfg_hooks->flush_pending_stmts (e);
997 /* Loop versioning uses the duplicate_loop_to_header_edge to create
998 a new version of the loop basic-blocks, the parameters here are
999 exactly the same as in duplicate_loop_to_header_edge or
1000 tree_duplicate_loop_to_header_edge; while in tree-ssa there is
1001 additional work to maintain ssa information that's why there is
1002 a need to call the tree_duplicate_loop_to_header_edge rather
1003 than duplicate_loop_to_header_edge when we are in tree mode. */
1005 cfg_hook_duplicate_loop_to_header_edge (struct loop *loop, edge e,
1007 sbitmap wont_exit, edge orig,
1008 VEC (edge, heap) **to_remove,
1011 gcc_assert (cfg_hooks->cfg_hook_duplicate_loop_to_header_edge);
1012 return cfg_hooks->cfg_hook_duplicate_loop_to_header_edge (loop, e,
1018 /* Conditional jumps are represented differently in trees and RTL,
1019 this hook takes a basic block that is known to have a cond jump
1020 at its end and extracts the taken and not taken eges out of it
1021 and store it in E1 and E2 respectively. */
1023 extract_cond_bb_edges (basic_block b, edge *e1, edge *e2)
1025 gcc_assert (cfg_hooks->extract_cond_bb_edges);
1026 cfg_hooks->extract_cond_bb_edges (b, e1, e2);
1029 /* Responsible for updating the ssa info (PHI nodes) on the
1030 new condition basic block that guards the versioned loop. */
1032 lv_adjust_loop_header_phi (basic_block first, basic_block second,
1033 basic_block new, edge e)
1035 if (cfg_hooks->lv_adjust_loop_header_phi)
1036 cfg_hooks->lv_adjust_loop_header_phi (first, second, new, e);
1039 /* Conditions in trees and RTL are different so we need
1040 a different handling when we add the condition to the
1043 lv_add_condition_to_bb (basic_block first, basic_block second,
1044 basic_block new, void *cond)
1046 gcc_assert (cfg_hooks->lv_add_condition_to_bb);
1047 cfg_hooks->lv_add_condition_to_bb (first, second, new, cond);