1 /* Control flow functions for trees.
2 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
3 Free Software Foundation, Inc.
4 Contributed by Diego Novillo <dnovillo@redhat.com>
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
24 #include "coretypes.h"
29 #include "hard-reg-set.h"
30 #include "basic-block.h"
36 #include "langhooks.h"
37 #include "diagnostic.h"
38 #include "tree-flow.h"
40 #include "tree-dump.h"
41 #include "tree-pass.h"
45 #include "cfglayout.h"
46 #include "tree-ssa-propagate.h"
47 #include "value-prof.h"
48 #include "pointer-set.h"
49 #include "tree-inline.h"
51 /* This file contains functions for building the Control Flow Graph (CFG)
52 for a function tree. */
54 /* Local declarations. */
56 /* Initial capacity for the basic block array. */
57 static const int initial_cfg_capacity = 20;
59 /* This hash table allows us to efficiently lookup all CASE_LABEL_EXPRs
60 which use a particular edge. The CASE_LABEL_EXPRs are chained together
61 via their TREE_CHAIN field, which we clear after we're done with the
62 hash table to prevent problems with duplication of SWITCH_EXPRs.
64 Access to this list of CASE_LABEL_EXPRs allows us to efficiently
65 update the case vector in response to edge redirections.
67 Right now this table is set up and torn down at key points in the
68 compilation process. It would be nice if we could make the table
69 more persistent. The key is getting notification of changes to
70 the CFG (particularly edge removal, creation and redirection). */
72 static struct pointer_map_t *edge_to_cases;
77 long num_merged_labels;
80 static struct cfg_stats_d cfg_stats;
82 /* Nonzero if we found a computed goto while building basic blocks. */
83 static bool found_computed_goto;
85 /* Basic blocks and flowgraphs. */
86 static basic_block create_bb (void *, void *, basic_block);
87 static void make_blocks (tree);
88 static void factor_computed_gotos (void);
91 static void make_edges (void);
92 static void make_cond_expr_edges (basic_block);
93 static void make_switch_expr_edges (basic_block);
94 static void make_goto_expr_edges (basic_block);
95 static edge tree_redirect_edge_and_branch (edge, basic_block);
96 static edge tree_try_redirect_by_replacing_jump (edge, basic_block);
97 static unsigned int split_critical_edges (void);
99 /* Various helpers. */
100 static inline bool stmt_starts_bb_p (const_tree, const_tree);
101 static int tree_verify_flow_info (void);
102 static void tree_make_forwarder_block (edge);
103 static void tree_cfg2vcg (FILE *);
104 static inline void change_bb_for_stmt (tree t, basic_block bb);
106 /* Flowgraph optimization and cleanup. */
107 static void tree_merge_blocks (basic_block, basic_block);
108 static bool tree_can_merge_blocks_p (basic_block, basic_block);
109 static void remove_bb (basic_block);
110 static edge find_taken_edge_computed_goto (basic_block, tree);
111 static edge find_taken_edge_cond_expr (basic_block, tree);
112 static edge find_taken_edge_switch_expr (basic_block, tree);
113 static tree find_case_label_for_value (tree, tree);
116 init_empty_tree_cfg (void)
118 /* Initialize the basic block array. */
120 profile_status = PROFILE_ABSENT;
121 n_basic_blocks = NUM_FIXED_BLOCKS;
122 last_basic_block = NUM_FIXED_BLOCKS;
123 basic_block_info = VEC_alloc (basic_block, gc, initial_cfg_capacity);
124 VEC_safe_grow_cleared (basic_block, gc, basic_block_info,
125 initial_cfg_capacity);
127 /* Build a mapping of labels to their associated blocks. */
128 label_to_block_map = VEC_alloc (basic_block, gc, initial_cfg_capacity);
129 VEC_safe_grow_cleared (basic_block, gc, label_to_block_map,
130 initial_cfg_capacity);
132 SET_BASIC_BLOCK (ENTRY_BLOCK, ENTRY_BLOCK_PTR);
133 SET_BASIC_BLOCK (EXIT_BLOCK, EXIT_BLOCK_PTR);
134 ENTRY_BLOCK_PTR->next_bb = EXIT_BLOCK_PTR;
135 EXIT_BLOCK_PTR->prev_bb = ENTRY_BLOCK_PTR;
138 /*---------------------------------------------------------------------------
140 ---------------------------------------------------------------------------*/
142 /* Entry point to the CFG builder for trees. TP points to the list of
143 statements to be added to the flowgraph. */
146 build_tree_cfg (tree *tp)
148 /* Register specific tree functions. */
149 tree_register_cfg_hooks ();
151 memset ((void *) &cfg_stats, 0, sizeof (cfg_stats));
153 init_empty_tree_cfg ();
155 found_computed_goto = 0;
158 /* Computed gotos are hell to deal with, especially if there are
159 lots of them with a large number of destinations. So we factor
160 them to a common computed goto location before we build the
161 edge list. After we convert back to normal form, we will un-factor
162 the computed gotos since factoring introduces an unwanted jump. */
163 if (found_computed_goto)
164 factor_computed_gotos ();
166 /* Make sure there is always at least one block, even if it's empty. */
167 if (n_basic_blocks == NUM_FIXED_BLOCKS)
168 create_empty_bb (ENTRY_BLOCK_PTR);
170 /* Adjust the size of the array. */
171 if (VEC_length (basic_block, basic_block_info) < (size_t) n_basic_blocks)
172 VEC_safe_grow_cleared (basic_block, gc, basic_block_info, n_basic_blocks);
174 /* To speed up statement iterator walks, we first purge dead labels. */
175 cleanup_dead_labels ();
177 /* Group case nodes to reduce the number of edges.
178 We do this after cleaning up dead labels because otherwise we miss
179 a lot of obvious case merging opportunities. */
180 group_case_labels ();
182 /* Create the edges of the flowgraph. */
184 cleanup_dead_labels ();
186 /* Debugging dumps. */
188 /* Write the flowgraph to a VCG file. */
190 int local_dump_flags;
191 FILE *vcg_file = dump_begin (TDI_vcg, &local_dump_flags);
194 tree_cfg2vcg (vcg_file);
195 dump_end (TDI_vcg, vcg_file);
199 #ifdef ENABLE_CHECKING
203 /* Dump a textual representation of the flowgraph. */
205 dump_tree_cfg (dump_file, dump_flags);
209 execute_build_cfg (void)
211 build_tree_cfg (&DECL_SAVED_TREE (current_function_decl));
215 struct tree_opt_pass pass_build_cfg =
219 execute_build_cfg, /* execute */
222 0, /* static_pass_number */
223 TV_TREE_CFG, /* tv_id */
224 PROP_gimple_leh, /* properties_required */
225 PROP_cfg, /* properties_provided */
226 0, /* properties_destroyed */
227 0, /* todo_flags_start */
228 TODO_verify_stmts | TODO_cleanup_cfg, /* todo_flags_finish */
232 /* Search the CFG for any computed gotos. If found, factor them to a
233 common computed goto site. Also record the location of that site so
234 that we can un-factor the gotos after we have converted back to
238 factor_computed_gotos (void)
241 tree factored_label_decl = NULL;
243 tree factored_computed_goto_label = NULL;
244 tree factored_computed_goto = NULL;
246 /* We know there are one or more computed gotos in this function.
247 Examine the last statement in each basic block to see if the block
248 ends with a computed goto. */
252 block_stmt_iterator bsi = bsi_last (bb);
257 last = bsi_stmt (bsi);
259 /* Ignore the computed goto we create when we factor the original
261 if (last == factored_computed_goto)
264 /* If the last statement is a computed goto, factor it. */
265 if (computed_goto_p (last))
269 /* The first time we find a computed goto we need to create
270 the factored goto block and the variable each original
271 computed goto will use for their goto destination. */
272 if (! factored_computed_goto)
274 basic_block new_bb = create_empty_bb (bb);
275 block_stmt_iterator new_bsi = bsi_start (new_bb);
277 /* Create the destination of the factored goto. Each original
278 computed goto will put its desired destination into this
279 variable and jump to the label we create immediately
281 var = create_tmp_var (ptr_type_node, "gotovar");
283 /* Build a label for the new block which will contain the
284 factored computed goto. */
285 factored_label_decl = create_artificial_label ();
286 factored_computed_goto_label
287 = build1 (LABEL_EXPR, void_type_node, factored_label_decl);
288 bsi_insert_after (&new_bsi, factored_computed_goto_label,
291 /* Build our new computed goto. */
292 factored_computed_goto = build1 (GOTO_EXPR, void_type_node, var);
293 bsi_insert_after (&new_bsi, factored_computed_goto,
297 /* Copy the original computed goto's destination into VAR. */
298 assignment = build_gimple_modify_stmt (var,
299 GOTO_DESTINATION (last));
300 bsi_insert_before (&bsi, assignment, BSI_SAME_STMT);
302 /* And re-vector the computed goto to the new destination. */
303 GOTO_DESTINATION (last) = factored_label_decl;
309 /* Build a flowgraph for the statement_list STMT_LIST. */
312 make_blocks (tree stmt_list)
314 tree_stmt_iterator i = tsi_start (stmt_list);
316 bool start_new_block = true;
317 bool first_stmt_of_list = true;
318 basic_block bb = ENTRY_BLOCK_PTR;
320 while (!tsi_end_p (i))
327 /* If the statement starts a new basic block or if we have determined
328 in a previous pass that we need to create a new block for STMT, do
330 if (start_new_block || stmt_starts_bb_p (stmt, prev_stmt))
332 if (!first_stmt_of_list)
333 stmt_list = tsi_split_statement_list_before (&i);
334 bb = create_basic_block (stmt_list, NULL, bb);
335 start_new_block = false;
338 /* Now add STMT to BB and create the subgraphs for special statement
340 set_bb_for_stmt (stmt, bb);
342 if (computed_goto_p (stmt))
343 found_computed_goto = true;
345 /* If STMT is a basic block terminator, set START_NEW_BLOCK for the
347 if (stmt_ends_bb_p (stmt))
348 start_new_block = true;
351 first_stmt_of_list = false;
356 /* Create and return a new empty basic block after bb AFTER. */
359 create_bb (void *h, void *e, basic_block after)
365 /* Create and initialize a new basic block. Since alloc_block uses
366 ggc_alloc_cleared to allocate a basic block, we do not have to
367 clear the newly allocated basic block here. */
370 bb->index = last_basic_block;
372 bb->il.tree = GGC_CNEW (struct tree_bb_info);
373 set_bb_stmt_list (bb, h ? (tree) h : alloc_stmt_list ());
375 /* Add the new block to the linked list of blocks. */
376 link_block (bb, after);
378 /* Grow the basic block array if needed. */
379 if ((size_t) last_basic_block == VEC_length (basic_block, basic_block_info))
381 size_t new_size = last_basic_block + (last_basic_block + 3) / 4;
382 VEC_safe_grow_cleared (basic_block, gc, basic_block_info, new_size);
385 /* Add the newly created block to the array. */
386 SET_BASIC_BLOCK (last_basic_block, bb);
395 /*---------------------------------------------------------------------------
397 ---------------------------------------------------------------------------*/
399 /* Fold COND_EXPR_COND of each COND_EXPR. */
402 fold_cond_expr_cond (void)
408 tree stmt = last_stmt (bb);
411 && TREE_CODE (stmt) == COND_EXPR)
416 fold_defer_overflow_warnings ();
417 cond = fold (COND_EXPR_COND (stmt));
418 zerop = integer_zerop (cond);
419 onep = integer_onep (cond);
420 fold_undefer_overflow_warnings (zerop || onep,
422 WARN_STRICT_OVERFLOW_CONDITIONAL);
424 COND_EXPR_COND (stmt) = boolean_false_node;
426 COND_EXPR_COND (stmt) = boolean_true_node;
431 /* Join all the blocks in the flowgraph. */
437 struct omp_region *cur_region = NULL;
439 /* Create an edge from entry to the first block with executable
441 make_edge (ENTRY_BLOCK_PTR, BASIC_BLOCK (NUM_FIXED_BLOCKS), EDGE_FALLTHRU);
443 /* Traverse the basic block array placing edges. */
446 tree last = last_stmt (bb);
451 enum tree_code code = TREE_CODE (last);
455 make_goto_expr_edges (bb);
459 make_edge (bb, EXIT_BLOCK_PTR, 0);
463 make_cond_expr_edges (bb);
467 make_switch_expr_edges (bb);
471 make_eh_edges (last);
476 /* If this function receives a nonlocal goto, then we need to
477 make edges from this call site to all the nonlocal goto
479 if (tree_can_make_abnormal_goto (last))
480 make_abnormal_goto_edges (bb, true);
482 /* If this statement has reachable exception handlers, then
483 create abnormal edges to them. */
484 make_eh_edges (last);
486 /* Some calls are known not to return. */
487 fallthru = !(call_expr_flags (last) & ECF_NORETURN);
493 case GIMPLE_MODIFY_STMT:
494 if (is_ctrl_altering_stmt (last))
496 /* A GIMPLE_MODIFY_STMT may have a CALL_EXPR on its RHS and
497 the CALL_EXPR may have an abnormal edge. Search the RHS
498 for this case and create any required edges. */
499 if (tree_can_make_abnormal_goto (last))
500 make_abnormal_goto_edges (bb, true);
502 make_eh_edges (last);
514 cur_region = new_omp_region (bb, code, cur_region);
519 cur_region = new_omp_region (bb, code, cur_region);
523 case OMP_SECTIONS_SWITCH:
528 case OMP_ATOMIC_LOAD:
529 case OMP_ATOMIC_STORE:
535 /* In the case of an OMP_SECTION, the edge will go somewhere
536 other than the next block. This will be created later. */
537 cur_region->exit = bb;
538 fallthru = cur_region->type != OMP_SECTION;
539 cur_region = cur_region->outer;
543 cur_region->cont = bb;
544 switch (cur_region->type)
547 /* Mark all OMP_FOR and OMP_CONTINUE succs edges as abnormal
548 to prevent splitting them. */
549 single_succ_edge (cur_region->entry)->flags |= EDGE_ABNORMAL;
550 /* Make the loopback edge. */
551 make_edge (bb, single_succ (cur_region->entry),
554 /* Create an edge from OMP_FOR to exit, which corresponds to
555 the case that the body of the loop is not executed at
557 make_edge (cur_region->entry, bb->next_bb, EDGE_ABNORMAL);
558 make_edge (bb, bb->next_bb, EDGE_FALLTHRU | EDGE_ABNORMAL);
563 /* Wire up the edges into and out of the nested sections. */
565 basic_block switch_bb = single_succ (cur_region->entry);
567 struct omp_region *i;
568 for (i = cur_region->inner; i ; i = i->next)
570 gcc_assert (i->type == OMP_SECTION);
571 make_edge (switch_bb, i->entry, 0);
572 make_edge (i->exit, bb, EDGE_FALLTHRU);
575 /* Make the loopback edge to the block with
576 OMP_SECTIONS_SWITCH. */
577 make_edge (bb, switch_bb, 0);
579 /* Make the edge from the switch to exit. */
580 make_edge (switch_bb, bb->next_bb, 0);
591 gcc_assert (!stmt_ends_bb_p (last));
599 make_edge (bb, bb->next_bb, EDGE_FALLTHRU);
605 /* Fold COND_EXPR_COND of each COND_EXPR. */
606 fold_cond_expr_cond ();
610 /* Create the edges for a COND_EXPR starting at block BB.
611 At this point, both clauses must contain only simple gotos. */
614 make_cond_expr_edges (basic_block bb)
616 tree entry = last_stmt (bb);
617 basic_block then_bb, else_bb;
618 tree then_label, else_label;
622 gcc_assert (TREE_CODE (entry) == COND_EXPR);
624 /* Entry basic blocks for each component. */
625 then_label = GOTO_DESTINATION (COND_EXPR_THEN (entry));
626 else_label = GOTO_DESTINATION (COND_EXPR_ELSE (entry));
627 then_bb = label_to_block (then_label);
628 else_bb = label_to_block (else_label);
630 e = make_edge (bb, then_bb, EDGE_TRUE_VALUE);
631 e->goto_locus = EXPR_LOCATION (COND_EXPR_THEN (entry));
632 e = make_edge (bb, else_bb, EDGE_FALSE_VALUE);
634 e->goto_locus = EXPR_LOCATION (COND_EXPR_ELSE (entry));
636 /* We do not need the gotos anymore. */
637 COND_EXPR_THEN (entry) = NULL_TREE;
638 COND_EXPR_ELSE (entry) = NULL_TREE;
642 /* Called for each element in the hash table (P) as we delete the
643 edge to cases hash table.
645 Clear all the TREE_CHAINs to prevent problems with copying of
646 SWITCH_EXPRs and structure sharing rules, then free the hash table
650 edge_to_cases_cleanup (const void *key ATTRIBUTE_UNUSED, void **value,
651 void *data ATTRIBUTE_UNUSED)
655 for (t = (tree) *value; t; t = next)
657 next = TREE_CHAIN (t);
658 TREE_CHAIN (t) = NULL;
665 /* Start recording information mapping edges to case labels. */
668 start_recording_case_labels (void)
670 gcc_assert (edge_to_cases == NULL);
671 edge_to_cases = pointer_map_create ();
674 /* Return nonzero if we are recording information for case labels. */
677 recording_case_labels_p (void)
679 return (edge_to_cases != NULL);
682 /* Stop recording information mapping edges to case labels and
683 remove any information we have recorded. */
685 end_recording_case_labels (void)
687 pointer_map_traverse (edge_to_cases, edge_to_cases_cleanup, NULL);
688 pointer_map_destroy (edge_to_cases);
689 edge_to_cases = NULL;
692 /* If we are inside a {start,end}_recording_cases block, then return
693 a chain of CASE_LABEL_EXPRs from T which reference E.
695 Otherwise return NULL. */
698 get_cases_for_edge (edge e, tree t)
704 /* If we are not recording cases, then we do not have CASE_LABEL_EXPR
705 chains available. Return NULL so the caller can detect this case. */
706 if (!recording_case_labels_p ())
709 slot = pointer_map_contains (edge_to_cases, e);
713 /* If we did not find E in the hash table, then this must be the first
714 time we have been queried for information about E & T. Add all the
715 elements from T to the hash table then perform the query again. */
717 vec = SWITCH_LABELS (t);
718 n = TREE_VEC_LENGTH (vec);
719 for (i = 0; i < n; i++)
721 tree elt = TREE_VEC_ELT (vec, i);
722 tree lab = CASE_LABEL (elt);
723 basic_block label_bb = label_to_block (lab);
724 edge this_edge = find_edge (e->src, label_bb);
726 /* Add it to the chain of CASE_LABEL_EXPRs referencing E, or create
728 slot = pointer_map_insert (edge_to_cases, this_edge);
729 TREE_CHAIN (elt) = (tree) *slot;
733 return (tree) *pointer_map_contains (edge_to_cases, e);
736 /* Create the edges for a SWITCH_EXPR starting at block BB.
737 At this point, the switch body has been lowered and the
738 SWITCH_LABELS filled in, so this is in effect a multi-way branch. */
741 make_switch_expr_edges (basic_block bb)
743 tree entry = last_stmt (bb);
747 vec = SWITCH_LABELS (entry);
748 n = TREE_VEC_LENGTH (vec);
750 for (i = 0; i < n; ++i)
752 tree lab = CASE_LABEL (TREE_VEC_ELT (vec, i));
753 basic_block label_bb = label_to_block (lab);
754 make_edge (bb, label_bb, 0);
759 /* Return the basic block holding label DEST. */
762 label_to_block_fn (struct function *ifun, tree dest)
764 int uid = LABEL_DECL_UID (dest);
766 /* We would die hard when faced by an undefined label. Emit a label to
767 the very first basic block. This will hopefully make even the dataflow
768 and undefined variable warnings quite right. */
769 if ((errorcount || sorrycount) && uid < 0)
771 block_stmt_iterator bsi =
772 bsi_start (BASIC_BLOCK (NUM_FIXED_BLOCKS));
775 stmt = build1 (LABEL_EXPR, void_type_node, dest);
776 bsi_insert_before (&bsi, stmt, BSI_NEW_STMT);
777 uid = LABEL_DECL_UID (dest);
779 if (VEC_length (basic_block, ifun->cfg->x_label_to_block_map)
780 <= (unsigned int) uid)
782 return VEC_index (basic_block, ifun->cfg->x_label_to_block_map, uid);
785 /* Create edges for an abnormal goto statement at block BB. If FOR_CALL
786 is true, the source statement is a CALL_EXPR instead of a GOTO_EXPR. */
789 make_abnormal_goto_edges (basic_block bb, bool for_call)
791 basic_block target_bb;
792 block_stmt_iterator bsi;
794 FOR_EACH_BB (target_bb)
795 for (bsi = bsi_start (target_bb); !bsi_end_p (bsi); bsi_next (&bsi))
797 tree target = bsi_stmt (bsi);
799 if (TREE_CODE (target) != LABEL_EXPR)
802 target = LABEL_EXPR_LABEL (target);
804 /* Make an edge to every label block that has been marked as a
805 potential target for a computed goto or a non-local goto. */
806 if ((FORCED_LABEL (target) && !for_call)
807 || (DECL_NONLOCAL (target) && for_call))
809 make_edge (bb, target_bb, EDGE_ABNORMAL);
815 /* Create edges for a goto statement at block BB. */
818 make_goto_expr_edges (basic_block bb)
820 block_stmt_iterator last = bsi_last (bb);
821 tree goto_t = bsi_stmt (last);
823 /* A simple GOTO creates normal edges. */
824 if (simple_goto_p (goto_t))
826 tree dest = GOTO_DESTINATION (goto_t);
827 edge e = make_edge (bb, label_to_block (dest), EDGE_FALLTHRU);
828 e->goto_locus = EXPR_LOCATION (goto_t);
829 bsi_remove (&last, true);
833 /* A computed GOTO creates abnormal edges. */
834 make_abnormal_goto_edges (bb, false);
838 /*---------------------------------------------------------------------------
840 ---------------------------------------------------------------------------*/
842 /* Cleanup useless labels in basic blocks. This is something we wish
843 to do early because it allows us to group case labels before creating
844 the edges for the CFG, and it speeds up block statement iterators in
846 We rerun this pass after CFG is created, to get rid of the labels that
847 are no longer referenced. After then we do not run it any more, since
848 (almost) no new labels should be created. */
850 /* A map from basic block index to the leading label of that block. */
851 static struct label_record
856 /* True if the label is referenced from somewhere. */
860 /* Callback for for_each_eh_region. Helper for cleanup_dead_labels. */
862 update_eh_label (struct eh_region *region)
864 tree old_label = get_eh_region_tree_label (region);
868 basic_block bb = label_to_block (old_label);
870 /* ??? After optimizing, there may be EH regions with labels
871 that have already been removed from the function body, so
872 there is no basic block for them. */
876 new_label = label_for_bb[bb->index].label;
877 label_for_bb[bb->index].used = true;
878 set_eh_region_tree_label (region, new_label);
882 /* Given LABEL return the first label in the same basic block. */
884 main_block_label (tree label)
886 basic_block bb = label_to_block (label);
887 tree main_label = label_for_bb[bb->index].label;
889 /* label_to_block possibly inserted undefined label into the chain. */
892 label_for_bb[bb->index].label = label;
896 label_for_bb[bb->index].used = true;
900 /* Cleanup redundant labels. This is a three-step process:
901 1) Find the leading label for each block.
902 2) Redirect all references to labels to the leading labels.
903 3) Cleanup all useless labels. */
906 cleanup_dead_labels (void)
909 label_for_bb = XCNEWVEC (struct label_record, last_basic_block);
911 /* Find a suitable label for each block. We use the first user-defined
912 label if there is one, or otherwise just the first label we see. */
915 block_stmt_iterator i;
917 for (i = bsi_start (bb); !bsi_end_p (i); bsi_next (&i))
919 tree label, stmt = bsi_stmt (i);
921 if (TREE_CODE (stmt) != LABEL_EXPR)
924 label = LABEL_EXPR_LABEL (stmt);
926 /* If we have not yet seen a label for the current block,
927 remember this one and see if there are more labels. */
928 if (!label_for_bb[bb->index].label)
930 label_for_bb[bb->index].label = label;
934 /* If we did see a label for the current block already, but it
935 is an artificially created label, replace it if the current
936 label is a user defined label. */
937 if (!DECL_ARTIFICIAL (label)
938 && DECL_ARTIFICIAL (label_for_bb[bb->index].label))
940 label_for_bb[bb->index].label = label;
946 /* Now redirect all jumps/branches to the selected label.
947 First do so for each block ending in a control statement. */
950 tree stmt = last_stmt (bb);
954 switch (TREE_CODE (stmt))
958 tree true_branch, false_branch;
960 true_branch = COND_EXPR_THEN (stmt);
961 false_branch = COND_EXPR_ELSE (stmt);
964 GOTO_DESTINATION (true_branch)
965 = main_block_label (GOTO_DESTINATION (true_branch));
967 GOTO_DESTINATION (false_branch)
968 = main_block_label (GOTO_DESTINATION (false_branch));
976 tree vec = SWITCH_LABELS (stmt);
977 size_t n = TREE_VEC_LENGTH (vec);
979 /* Replace all destination labels. */
980 for (i = 0; i < n; ++i)
982 tree elt = TREE_VEC_ELT (vec, i);
983 tree label = main_block_label (CASE_LABEL (elt));
984 CASE_LABEL (elt) = label;
989 /* We have to handle GOTO_EXPRs until they're removed, and we don't
990 remove them until after we've created the CFG edges. */
992 if (! computed_goto_p (stmt))
994 GOTO_DESTINATION (stmt)
995 = main_block_label (GOTO_DESTINATION (stmt));
1004 for_each_eh_region (update_eh_label);
1006 /* Finally, purge dead labels. All user-defined labels and labels that
1007 can be the target of non-local gotos and labels which have their
1008 address taken are preserved. */
1011 block_stmt_iterator i;
1012 tree label_for_this_bb = label_for_bb[bb->index].label;
1014 if (!label_for_this_bb)
1017 /* If the main label of the block is unused, we may still remove it. */
1018 if (!label_for_bb[bb->index].used)
1019 label_for_this_bb = NULL;
1021 for (i = bsi_start (bb); !bsi_end_p (i); )
1023 tree label, stmt = bsi_stmt (i);
1025 if (TREE_CODE (stmt) != LABEL_EXPR)
1028 label = LABEL_EXPR_LABEL (stmt);
1030 if (label == label_for_this_bb
1031 || ! DECL_ARTIFICIAL (label)
1032 || DECL_NONLOCAL (label)
1033 || FORCED_LABEL (label))
1036 bsi_remove (&i, true);
1040 free (label_for_bb);
1043 /* Look for blocks ending in a multiway branch (a SWITCH_EXPR in GIMPLE),
1044 and scan the sorted vector of cases. Combine the ones jumping to the
1046 Eg. three separate entries 1: 2: 3: become one entry 1..3: */
1049 group_case_labels (void)
1055 tree stmt = last_stmt (bb);
1056 if (stmt && TREE_CODE (stmt) == SWITCH_EXPR)
1058 tree labels = SWITCH_LABELS (stmt);
1059 int old_size = TREE_VEC_LENGTH (labels);
1060 int i, j, new_size = old_size;
1061 tree default_case = TREE_VEC_ELT (labels, old_size - 1);
1064 /* The default label is always the last case in a switch
1065 statement after gimplification. */
1066 default_label = CASE_LABEL (default_case);
1068 /* Look for possible opportunities to merge cases.
1069 Ignore the last element of the label vector because it
1070 must be the default case. */
1072 while (i < old_size - 1)
1074 tree base_case, base_label, base_high;
1075 base_case = TREE_VEC_ELT (labels, i);
1077 gcc_assert (base_case);
1078 base_label = CASE_LABEL (base_case);
1080 /* Discard cases that have the same destination as the
1082 if (base_label == default_label)
1084 TREE_VEC_ELT (labels, i) = NULL_TREE;
1090 base_high = CASE_HIGH (base_case) ?
1091 CASE_HIGH (base_case) : CASE_LOW (base_case);
1093 /* Try to merge case labels. Break out when we reach the end
1094 of the label vector or when we cannot merge the next case
1095 label with the current one. */
1096 while (i < old_size - 1)
1098 tree merge_case = TREE_VEC_ELT (labels, i);
1099 tree merge_label = CASE_LABEL (merge_case);
1100 tree t = int_const_binop (PLUS_EXPR, base_high,
1101 integer_one_node, 1);
1103 /* Merge the cases if they jump to the same place,
1104 and their ranges are consecutive. */
1105 if (merge_label == base_label
1106 && tree_int_cst_equal (CASE_LOW (merge_case), t))
1108 base_high = CASE_HIGH (merge_case) ?
1109 CASE_HIGH (merge_case) : CASE_LOW (merge_case);
1110 CASE_HIGH (base_case) = base_high;
1111 TREE_VEC_ELT (labels, i) = NULL_TREE;
1120 /* Compress the case labels in the label vector, and adjust the
1121 length of the vector. */
1122 for (i = 0, j = 0; i < new_size; i++)
1124 while (! TREE_VEC_ELT (labels, j))
1126 TREE_VEC_ELT (labels, i) = TREE_VEC_ELT (labels, j++);
1128 TREE_VEC_LENGTH (labels) = new_size;
1133 /* Checks whether we can merge block B into block A. */
1136 tree_can_merge_blocks_p (basic_block a, basic_block b)
1139 block_stmt_iterator bsi;
1142 if (!single_succ_p (a))
1145 if (single_succ_edge (a)->flags & EDGE_ABNORMAL)
1148 if (single_succ (a) != b)
1151 if (!single_pred_p (b))
1154 if (b == EXIT_BLOCK_PTR)
1157 /* If A ends by a statement causing exceptions or something similar, we
1158 cannot merge the blocks. */
1159 /* This CONST_CAST is okay because last_stmt doesn't modify its
1160 argument and the return value is assign to a const_tree. */
1161 stmt = last_stmt (CONST_CAST_BB (a));
1162 if (stmt && stmt_ends_bb_p (stmt))
1165 /* Do not allow a block with only a non-local label to be merged. */
1166 if (stmt && TREE_CODE (stmt) == LABEL_EXPR
1167 && DECL_NONLOCAL (LABEL_EXPR_LABEL (stmt)))
1170 /* It must be possible to eliminate all phi nodes in B. If ssa form
1171 is not up-to-date, we cannot eliminate any phis; however, if only
1172 some symbols as whole are marked for renaming, this is not a problem,
1173 as phi nodes for those symbols are irrelevant in updating anyway. */
1174 phi = phi_nodes (b);
1177 if (name_mappings_registered_p ())
1180 for (; phi; phi = PHI_CHAIN (phi))
1181 if (!is_gimple_reg (PHI_RESULT (phi))
1182 && !may_propagate_copy (PHI_RESULT (phi), PHI_ARG_DEF (phi, 0)))
1186 /* Do not remove user labels. */
1187 for (bsi = bsi_start (b); !bsi_end_p (bsi); bsi_next (&bsi))
1189 stmt = bsi_stmt (bsi);
1190 if (TREE_CODE (stmt) != LABEL_EXPR)
1192 if (!DECL_ARTIFICIAL (LABEL_EXPR_LABEL (stmt)))
1196 /* Protect the loop latches. */
1198 && b->loop_father->latch == b)
1204 /* Replaces all uses of NAME by VAL. */
1207 replace_uses_by (tree name, tree val)
1209 imm_use_iterator imm_iter;
1214 FOR_EACH_IMM_USE_STMT (stmt, imm_iter, name)
1216 if (TREE_CODE (stmt) != PHI_NODE)
1217 push_stmt_changes (&stmt);
1219 FOR_EACH_IMM_USE_ON_STMT (use, imm_iter)
1221 replace_exp (use, val);
1223 if (TREE_CODE (stmt) == PHI_NODE)
1225 e = PHI_ARG_EDGE (stmt, PHI_ARG_INDEX_FROM_USE (use));
1226 if (e->flags & EDGE_ABNORMAL)
1228 /* This can only occur for virtual operands, since
1229 for the real ones SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name))
1230 would prevent replacement. */
1231 gcc_assert (!is_gimple_reg (name));
1232 SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val) = 1;
1237 if (TREE_CODE (stmt) != PHI_NODE)
1241 fold_stmt_inplace (stmt);
1242 if (cfgcleanup_altered_bbs)
1243 bitmap_set_bit (cfgcleanup_altered_bbs, bb_for_stmt (stmt)->index);
1245 /* FIXME. This should go in pop_stmt_changes. */
1246 rhs = get_rhs (stmt);
1247 if (TREE_CODE (rhs) == ADDR_EXPR)
1248 recompute_tree_invariant_for_addr_expr (rhs);
1250 maybe_clean_or_replace_eh_stmt (stmt, stmt);
1252 pop_stmt_changes (&stmt);
1256 gcc_assert (has_zero_uses (name));
1258 /* Also update the trees stored in loop structures. */
1264 FOR_EACH_LOOP (li, loop, 0)
1266 substitute_in_loop_info (loop, name, val);
1271 /* Merge block B into block A. */
1274 tree_merge_blocks (basic_block a, basic_block b)
1276 block_stmt_iterator bsi;
1277 tree_stmt_iterator last;
1281 fprintf (dump_file, "Merging blocks %d and %d\n", a->index, b->index);
1283 /* Remove all single-valued PHI nodes from block B of the form
1284 V_i = PHI <V_j> by propagating V_j to all the uses of V_i. */
1286 for (phi = phi_nodes (b); phi; phi = phi_nodes (b))
1288 tree def = PHI_RESULT (phi), use = PHI_ARG_DEF (phi, 0);
1290 bool may_replace_uses = may_propagate_copy (def, use);
1292 /* In case we maintain loop closed ssa form, do not propagate arguments
1293 of loop exit phi nodes. */
1295 && loops_state_satisfies_p (LOOP_CLOSED_SSA)
1296 && is_gimple_reg (def)
1297 && TREE_CODE (use) == SSA_NAME
1298 && a->loop_father != b->loop_father)
1299 may_replace_uses = false;
1301 if (!may_replace_uses)
1303 gcc_assert (is_gimple_reg (def));
1305 /* Note that just emitting the copies is fine -- there is no problem
1306 with ordering of phi nodes. This is because A is the single
1307 predecessor of B, therefore results of the phi nodes cannot
1308 appear as arguments of the phi nodes. */
1309 copy = build_gimple_modify_stmt (def, use);
1310 bsi_insert_after (&bsi, copy, BSI_NEW_STMT);
1311 SSA_NAME_DEF_STMT (def) = copy;
1312 remove_phi_node (phi, NULL, false);
1316 /* If we deal with a PHI for virtual operands, we can simply
1317 propagate these without fussing with folding or updating
1319 if (!is_gimple_reg (def))
1321 imm_use_iterator iter;
1322 use_operand_p use_p;
1325 FOR_EACH_IMM_USE_STMT (stmt, iter, def)
1326 FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
1327 SET_USE (use_p, use);
1330 replace_uses_by (def, use);
1331 remove_phi_node (phi, NULL, true);
1335 /* Ensure that B follows A. */
1336 move_block_after (b, a);
1338 gcc_assert (single_succ_edge (a)->flags & EDGE_FALLTHRU);
1339 gcc_assert (!last_stmt (a) || !stmt_ends_bb_p (last_stmt (a)));
1341 /* Remove labels from B and set bb_for_stmt to A for other statements. */
1342 for (bsi = bsi_start (b); !bsi_end_p (bsi);)
1344 if (TREE_CODE (bsi_stmt (bsi)) == LABEL_EXPR)
1346 tree label = bsi_stmt (bsi);
1348 bsi_remove (&bsi, false);
1349 /* Now that we can thread computed gotos, we might have
1350 a situation where we have a forced label in block B
1351 However, the label at the start of block B might still be
1352 used in other ways (think about the runtime checking for
1353 Fortran assigned gotos). So we can not just delete the
1354 label. Instead we move the label to the start of block A. */
1355 if (FORCED_LABEL (LABEL_EXPR_LABEL (label)))
1357 block_stmt_iterator dest_bsi = bsi_start (a);
1358 bsi_insert_before (&dest_bsi, label, BSI_NEW_STMT);
1363 change_bb_for_stmt (bsi_stmt (bsi), a);
1368 /* Merge the chains. */
1369 last = tsi_last (bb_stmt_list (a));
1370 tsi_link_after (&last, bb_stmt_list (b), TSI_NEW_STMT);
1371 set_bb_stmt_list (b, NULL_TREE);
1373 if (cfgcleanup_altered_bbs)
1374 bitmap_set_bit (cfgcleanup_altered_bbs, a->index);
1378 /* Return the one of two successors of BB that is not reachable by a
1379 reached by a complex edge, if there is one. Else, return BB. We use
1380 this in optimizations that use post-dominators for their heuristics,
1381 to catch the cases in C++ where function calls are involved. */
1384 single_noncomplex_succ (basic_block bb)
1387 if (EDGE_COUNT (bb->succs) != 2)
1390 e0 = EDGE_SUCC (bb, 0);
1391 e1 = EDGE_SUCC (bb, 1);
1392 if (e0->flags & EDGE_COMPLEX)
1394 if (e1->flags & EDGE_COMPLEX)
1401 /* Walk the function tree removing unnecessary statements.
1403 * Empty statement nodes are removed
1405 * Unnecessary TRY_FINALLY and TRY_CATCH blocks are removed
1407 * Unnecessary COND_EXPRs are removed
1409 * Some unnecessary BIND_EXPRs are removed
1411 Clearly more work could be done. The trick is doing the analysis
1412 and removal fast enough to be a net improvement in compile times.
1414 Note that when we remove a control structure such as a COND_EXPR
1415 BIND_EXPR, or TRY block, we will need to repeat this optimization pass
1416 to ensure we eliminate all the useless code. */
1427 static void remove_useless_stmts_1 (tree *, struct rus_data *);
1430 remove_useless_stmts_warn_notreached (tree stmt)
1432 if (EXPR_HAS_LOCATION (stmt))
1434 location_t loc = EXPR_LOCATION (stmt);
1435 if (LOCATION_LINE (loc) > 0)
1437 warning (OPT_Wunreachable_code, "%Hwill never be executed", &loc);
1442 switch (TREE_CODE (stmt))
1444 case STATEMENT_LIST:
1446 tree_stmt_iterator i;
1447 for (i = tsi_start (stmt); !tsi_end_p (i); tsi_next (&i))
1448 if (remove_useless_stmts_warn_notreached (tsi_stmt (i)))
1454 if (remove_useless_stmts_warn_notreached (COND_EXPR_COND (stmt)))
1456 if (remove_useless_stmts_warn_notreached (COND_EXPR_THEN (stmt)))
1458 if (remove_useless_stmts_warn_notreached (COND_EXPR_ELSE (stmt)))
1462 case TRY_FINALLY_EXPR:
1463 case TRY_CATCH_EXPR:
1464 if (remove_useless_stmts_warn_notreached (TREE_OPERAND (stmt, 0)))
1466 if (remove_useless_stmts_warn_notreached (TREE_OPERAND (stmt, 1)))
1471 return remove_useless_stmts_warn_notreached (CATCH_BODY (stmt));
1472 case EH_FILTER_EXPR:
1473 return remove_useless_stmts_warn_notreached (EH_FILTER_FAILURE (stmt));
1475 return remove_useless_stmts_warn_notreached (BIND_EXPR_BLOCK (stmt));
1478 /* Not a live container. */
1486 remove_useless_stmts_cond (tree *stmt_p, struct rus_data *data)
1488 tree then_clause, else_clause, cond;
1489 bool save_has_label, then_has_label, else_has_label;
1491 save_has_label = data->has_label;
1492 data->has_label = false;
1493 data->last_goto = NULL;
1495 remove_useless_stmts_1 (&COND_EXPR_THEN (*stmt_p), data);
1497 then_has_label = data->has_label;
1498 data->has_label = false;
1499 data->last_goto = NULL;
1501 remove_useless_stmts_1 (&COND_EXPR_ELSE (*stmt_p), data);
1503 else_has_label = data->has_label;
1504 data->has_label = save_has_label | then_has_label | else_has_label;
1506 then_clause = COND_EXPR_THEN (*stmt_p);
1507 else_clause = COND_EXPR_ELSE (*stmt_p);
1508 cond = fold (COND_EXPR_COND (*stmt_p));
1510 /* If neither arm does anything at all, we can remove the whole IF. */
1511 if (!TREE_SIDE_EFFECTS (then_clause) && !TREE_SIDE_EFFECTS (else_clause))
1513 *stmt_p = build_empty_stmt ();
1514 data->repeat = true;
1517 /* If there are no reachable statements in an arm, then we can
1518 zap the entire conditional. */
1519 else if (integer_nonzerop (cond) && !else_has_label)
1521 if (warn_notreached)
1522 remove_useless_stmts_warn_notreached (else_clause);
1523 *stmt_p = then_clause;
1524 data->repeat = true;
1526 else if (integer_zerop (cond) && !then_has_label)
1528 if (warn_notreached)
1529 remove_useless_stmts_warn_notreached (then_clause);
1530 *stmt_p = else_clause;
1531 data->repeat = true;
1534 /* Check a couple of simple things on then/else with single stmts. */
1537 tree then_stmt = expr_only (then_clause);
1538 tree else_stmt = expr_only (else_clause);
1540 /* Notice branches to a common destination. */
1541 if (then_stmt && else_stmt
1542 && TREE_CODE (then_stmt) == GOTO_EXPR
1543 && TREE_CODE (else_stmt) == GOTO_EXPR
1544 && (GOTO_DESTINATION (then_stmt) == GOTO_DESTINATION (else_stmt)))
1546 *stmt_p = then_stmt;
1547 data->repeat = true;
1550 /* If the THEN/ELSE clause merely assigns a value to a variable or
1551 parameter which is already known to contain that value, then
1552 remove the useless THEN/ELSE clause. */
1553 else if (TREE_CODE (cond) == VAR_DECL || TREE_CODE (cond) == PARM_DECL)
1556 && TREE_CODE (else_stmt) == GIMPLE_MODIFY_STMT
1557 && GIMPLE_STMT_OPERAND (else_stmt, 0) == cond
1558 && integer_zerop (GIMPLE_STMT_OPERAND (else_stmt, 1)))
1559 COND_EXPR_ELSE (*stmt_p) = alloc_stmt_list ();
1561 else if ((TREE_CODE (cond) == EQ_EXPR || TREE_CODE (cond) == NE_EXPR)
1562 && (TREE_CODE (TREE_OPERAND (cond, 0)) == VAR_DECL
1563 || TREE_CODE (TREE_OPERAND (cond, 0)) == PARM_DECL)
1564 && TREE_CONSTANT (TREE_OPERAND (cond, 1)))
1566 tree stmt = (TREE_CODE (cond) == EQ_EXPR
1567 ? then_stmt : else_stmt);
1568 tree *location = (TREE_CODE (cond) == EQ_EXPR
1569 ? &COND_EXPR_THEN (*stmt_p)
1570 : &COND_EXPR_ELSE (*stmt_p));
1573 && TREE_CODE (stmt) == GIMPLE_MODIFY_STMT
1574 && GIMPLE_STMT_OPERAND (stmt, 0) == TREE_OPERAND (cond, 0)
1575 && GIMPLE_STMT_OPERAND (stmt, 1) == TREE_OPERAND (cond, 1))
1576 *location = alloc_stmt_list ();
1580 /* Protect GOTOs in the arm of COND_EXPRs from being removed. They
1581 would be re-introduced during lowering. */
1582 data->last_goto = NULL;
1587 remove_useless_stmts_tf (tree *stmt_p, struct rus_data *data)
1589 bool save_may_branch, save_may_throw;
1590 bool this_may_branch, this_may_throw;
1592 /* Collect may_branch and may_throw information for the body only. */
1593 save_may_branch = data->may_branch;
1594 save_may_throw = data->may_throw;
1595 data->may_branch = false;
1596 data->may_throw = false;
1597 data->last_goto = NULL;
1599 remove_useless_stmts_1 (&TREE_OPERAND (*stmt_p, 0), data);
1601 this_may_branch = data->may_branch;
1602 this_may_throw = data->may_throw;
1603 data->may_branch |= save_may_branch;
1604 data->may_throw |= save_may_throw;
1605 data->last_goto = NULL;
1607 remove_useless_stmts_1 (&TREE_OPERAND (*stmt_p, 1), data);
1609 /* If the body is empty, then we can emit the FINALLY block without
1610 the enclosing TRY_FINALLY_EXPR. */
1611 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (*stmt_p, 0)))
1613 *stmt_p = TREE_OPERAND (*stmt_p, 1);
1614 data->repeat = true;
1617 /* If the handler is empty, then we can emit the TRY block without
1618 the enclosing TRY_FINALLY_EXPR. */
1619 else if (!TREE_SIDE_EFFECTS (TREE_OPERAND (*stmt_p, 1)))
1621 *stmt_p = TREE_OPERAND (*stmt_p, 0);
1622 data->repeat = true;
1625 /* If the body neither throws, nor branches, then we can safely
1626 string the TRY and FINALLY blocks together. */
1627 else if (!this_may_branch && !this_may_throw)
1629 tree stmt = *stmt_p;
1630 *stmt_p = TREE_OPERAND (stmt, 0);
1631 append_to_statement_list (TREE_OPERAND (stmt, 1), stmt_p);
1632 data->repeat = true;
1638 remove_useless_stmts_tc (tree *stmt_p, struct rus_data *data)
1640 bool save_may_throw, this_may_throw;
1641 tree_stmt_iterator i;
1644 /* Collect may_throw information for the body only. */
1645 save_may_throw = data->may_throw;
1646 data->may_throw = false;
1647 data->last_goto = NULL;
1649 remove_useless_stmts_1 (&TREE_OPERAND (*stmt_p, 0), data);
1651 this_may_throw = data->may_throw;
1652 data->may_throw = save_may_throw;
1654 /* If the body cannot throw, then we can drop the entire TRY_CATCH_EXPR. */
1655 if (!this_may_throw)
1657 if (warn_notreached)
1658 remove_useless_stmts_warn_notreached (TREE_OPERAND (*stmt_p, 1));
1659 *stmt_p = TREE_OPERAND (*stmt_p, 0);
1660 data->repeat = true;
1664 /* Process the catch clause specially. We may be able to tell that
1665 no exceptions propagate past this point. */
1667 this_may_throw = true;
1668 i = tsi_start (TREE_OPERAND (*stmt_p, 1));
1669 stmt = tsi_stmt (i);
1670 data->last_goto = NULL;
1672 switch (TREE_CODE (stmt))
1675 for (; !tsi_end_p (i); tsi_next (&i))
1677 stmt = tsi_stmt (i);
1678 /* If we catch all exceptions, then the body does not
1679 propagate exceptions past this point. */
1680 if (CATCH_TYPES (stmt) == NULL)
1681 this_may_throw = false;
1682 data->last_goto = NULL;
1683 remove_useless_stmts_1 (&CATCH_BODY (stmt), data);
1687 case EH_FILTER_EXPR:
1688 if (EH_FILTER_MUST_NOT_THROW (stmt))
1689 this_may_throw = false;
1690 else if (EH_FILTER_TYPES (stmt) == NULL)
1691 this_may_throw = false;
1692 remove_useless_stmts_1 (&EH_FILTER_FAILURE (stmt), data);
1696 /* Otherwise this is a cleanup. */
1697 remove_useless_stmts_1 (&TREE_OPERAND (*stmt_p, 1), data);
1699 /* If the cleanup is empty, then we can emit the TRY block without
1700 the enclosing TRY_CATCH_EXPR. */
1701 if (!TREE_SIDE_EFFECTS (TREE_OPERAND (*stmt_p, 1)))
1703 *stmt_p = TREE_OPERAND (*stmt_p, 0);
1704 data->repeat = true;
1708 data->may_throw |= this_may_throw;
1713 remove_useless_stmts_bind (tree *stmt_p, struct rus_data *data)
1717 /* First remove anything underneath the BIND_EXPR. */
1718 remove_useless_stmts_1 (&BIND_EXPR_BODY (*stmt_p), data);
1720 /* If the BIND_EXPR has no variables, then we can pull everything
1721 up one level and remove the BIND_EXPR, unless this is the toplevel
1722 BIND_EXPR for the current function or an inlined function.
1724 When this situation occurs we will want to apply this
1725 optimization again. */
1726 block = BIND_EXPR_BLOCK (*stmt_p);
1727 if (BIND_EXPR_VARS (*stmt_p) == NULL_TREE
1728 && *stmt_p != DECL_SAVED_TREE (current_function_decl)
1730 || ! BLOCK_ABSTRACT_ORIGIN (block)
1731 || (TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block))
1734 *stmt_p = BIND_EXPR_BODY (*stmt_p);
1735 data->repeat = true;
1741 remove_useless_stmts_goto (tree *stmt_p, struct rus_data *data)
1743 tree dest = GOTO_DESTINATION (*stmt_p);
1745 data->may_branch = true;
1746 data->last_goto = NULL;
1748 /* Record the last goto expr, so that we can delete it if unnecessary. */
1749 if (TREE_CODE (dest) == LABEL_DECL)
1750 data->last_goto = stmt_p;
1755 remove_useless_stmts_label (tree *stmt_p, struct rus_data *data)
1757 tree label = LABEL_EXPR_LABEL (*stmt_p);
1759 data->has_label = true;
1761 /* We do want to jump across non-local label receiver code. */
1762 if (DECL_NONLOCAL (label))
1763 data->last_goto = NULL;
1765 else if (data->last_goto && GOTO_DESTINATION (*data->last_goto) == label)
1767 *data->last_goto = build_empty_stmt ();
1768 data->repeat = true;
1771 /* ??? Add something here to delete unused labels. */
1775 /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its
1776 decl. This allows us to eliminate redundant or useless
1777 calls to "const" functions.
1779 Gimplifier already does the same operation, but we may notice functions
1780 being const and pure once their calls has been gimplified, so we need
1781 to update the flag. */
1784 update_call_expr_flags (tree call)
1786 tree decl = get_callee_fndecl (call);
1789 if (call_expr_flags (call) & (ECF_CONST | ECF_PURE))
1790 TREE_SIDE_EFFECTS (call) = 0;
1791 if (TREE_NOTHROW (decl))
1792 TREE_NOTHROW (call) = 1;
1796 /* T is CALL_EXPR. Set current_function_calls_* flags. */
1799 notice_special_calls (tree t)
1801 int flags = call_expr_flags (t);
1803 if (flags & ECF_MAY_BE_ALLOCA)
1804 current_function_calls_alloca = true;
1805 if (flags & ECF_RETURNS_TWICE)
1806 current_function_calls_setjmp = true;
1810 /* Clear flags set by notice_special_calls. Used by dead code removal
1811 to update the flags. */
1814 clear_special_calls (void)
1816 current_function_calls_alloca = false;
1817 current_function_calls_setjmp = false;
1822 remove_useless_stmts_1 (tree *tp, struct rus_data *data)
1826 switch (TREE_CODE (t))
1829 remove_useless_stmts_cond (tp, data);
1832 case TRY_FINALLY_EXPR:
1833 remove_useless_stmts_tf (tp, data);
1836 case TRY_CATCH_EXPR:
1837 remove_useless_stmts_tc (tp, data);
1841 remove_useless_stmts_bind (tp, data);
1845 remove_useless_stmts_goto (tp, data);
1849 remove_useless_stmts_label (tp, data);
1854 data->last_goto = NULL;
1855 data->may_branch = true;
1860 data->last_goto = NULL;
1861 notice_special_calls (t);
1862 update_call_expr_flags (t);
1863 if (tree_could_throw_p (t))
1864 data->may_throw = true;
1870 case GIMPLE_MODIFY_STMT:
1871 data->last_goto = NULL;
1873 op = get_call_expr_in (t);
1876 update_call_expr_flags (op);
1877 notice_special_calls (op);
1879 if (tree_could_throw_p (t))
1880 data->may_throw = true;
1883 case STATEMENT_LIST:
1885 tree_stmt_iterator i = tsi_start (t);
1886 while (!tsi_end_p (i))
1889 if (IS_EMPTY_STMT (t))
1895 remove_useless_stmts_1 (tsi_stmt_ptr (i), data);
1898 if (TREE_CODE (t) == STATEMENT_LIST)
1900 tsi_link_before (&i, t, TSI_SAME_STMT);
1910 data->last_goto = NULL;
1914 data->last_goto = NULL;
1920 remove_useless_stmts (void)
1922 struct rus_data data;
1924 clear_special_calls ();
1928 memset (&data, 0, sizeof (data));
1929 remove_useless_stmts_1 (&DECL_SAVED_TREE (current_function_decl), &data);
1931 while (data.repeat);
1936 struct tree_opt_pass pass_remove_useless_stmts =
1938 "useless", /* name */
1940 remove_useless_stmts, /* execute */
1943 0, /* static_pass_number */
1945 PROP_gimple_any, /* properties_required */
1946 0, /* properties_provided */
1947 0, /* properties_destroyed */
1948 0, /* todo_flags_start */
1949 TODO_dump_func, /* todo_flags_finish */
1953 /* Remove PHI nodes associated with basic block BB and all edges out of BB. */
1956 remove_phi_nodes_and_edges_for_unreachable_block (basic_block bb)
1960 /* Since this block is no longer reachable, we can just delete all
1961 of its PHI nodes. */
1962 phi = phi_nodes (bb);
1965 tree next = PHI_CHAIN (phi);
1966 remove_phi_node (phi, NULL_TREE, true);
1970 /* Remove edges to BB's successors. */
1971 while (EDGE_COUNT (bb->succs) > 0)
1972 remove_edge (EDGE_SUCC (bb, 0));
1976 /* Remove statements of basic block BB. */
1979 remove_bb (basic_block bb)
1981 block_stmt_iterator i;
1982 source_location loc = UNKNOWN_LOCATION;
1986 fprintf (dump_file, "Removing basic block %d\n", bb->index);
1987 if (dump_flags & TDF_DETAILS)
1989 dump_bb (bb, dump_file, 0);
1990 fprintf (dump_file, "\n");
1996 struct loop *loop = bb->loop_father;
1998 /* If a loop gets removed, clean up the information associated
2000 if (loop->latch == bb
2001 || loop->header == bb)
2002 free_numbers_of_iterations_estimates_loop (loop);
2005 /* Remove all the instructions in the block. */
2006 if (bb_stmt_list (bb) != NULL_TREE)
2008 for (i = bsi_start (bb); !bsi_end_p (i);)
2010 tree stmt = bsi_stmt (i);
2011 if (TREE_CODE (stmt) == LABEL_EXPR
2012 && (FORCED_LABEL (LABEL_EXPR_LABEL (stmt))
2013 || DECL_NONLOCAL (LABEL_EXPR_LABEL (stmt))))
2016 block_stmt_iterator new_bsi;
2018 /* A non-reachable non-local label may still be referenced.
2019 But it no longer needs to carry the extra semantics of
2021 if (DECL_NONLOCAL (LABEL_EXPR_LABEL (stmt)))
2023 DECL_NONLOCAL (LABEL_EXPR_LABEL (stmt)) = 0;
2024 FORCED_LABEL (LABEL_EXPR_LABEL (stmt)) = 1;
2027 new_bb = bb->prev_bb;
2028 new_bsi = bsi_start (new_bb);
2029 bsi_remove (&i, false);
2030 bsi_insert_before (&new_bsi, stmt, BSI_NEW_STMT);
2034 /* Release SSA definitions if we are in SSA. Note that we
2035 may be called when not in SSA. For example,
2036 final_cleanup calls this function via
2037 cleanup_tree_cfg. */
2038 if (gimple_in_ssa_p (cfun))
2039 release_defs (stmt);
2041 bsi_remove (&i, true);
2044 /* Don't warn for removed gotos. Gotos are often removed due to
2045 jump threading, thus resulting in bogus warnings. Not great,
2046 since this way we lose warnings for gotos in the original
2047 program that are indeed unreachable. */
2048 if (TREE_CODE (stmt) != GOTO_EXPR && EXPR_HAS_LOCATION (stmt) && !loc)
2050 if (EXPR_HAS_LOCATION (stmt))
2051 loc = EXPR_LOCATION (stmt);
2056 /* If requested, give a warning that the first statement in the
2057 block is unreachable. We walk statements backwards in the
2058 loop above, so the last statement we process is the first statement
2060 if (loc > BUILTINS_LOCATION && LOCATION_LINE (loc) > 0)
2061 warning (OPT_Wunreachable_code, "%Hwill never be executed", &loc);
2063 remove_phi_nodes_and_edges_for_unreachable_block (bb);
2068 /* Given a basic block BB ending with COND_EXPR or SWITCH_EXPR, and a
2069 predicate VAL, return the edge that will be taken out of the block.
2070 If VAL does not match a unique edge, NULL is returned. */
2073 find_taken_edge (basic_block bb, tree val)
2077 stmt = last_stmt (bb);
2080 gcc_assert (is_ctrl_stmt (stmt));
2083 if (! is_gimple_min_invariant (val))
2086 if (TREE_CODE (stmt) == COND_EXPR)
2087 return find_taken_edge_cond_expr (bb, val);
2089 if (TREE_CODE (stmt) == SWITCH_EXPR)
2090 return find_taken_edge_switch_expr (bb, val);
2092 if (computed_goto_p (stmt))
2094 /* Only optimize if the argument is a label, if the argument is
2095 not a label then we can not construct a proper CFG.
2097 It may be the case that we only need to allow the LABEL_REF to
2098 appear inside an ADDR_EXPR, but we also allow the LABEL_REF to
2099 appear inside a LABEL_EXPR just to be safe. */
2100 if ((TREE_CODE (val) == ADDR_EXPR || TREE_CODE (val) == LABEL_EXPR)
2101 && TREE_CODE (TREE_OPERAND (val, 0)) == LABEL_DECL)
2102 return find_taken_edge_computed_goto (bb, TREE_OPERAND (val, 0));
2109 /* Given a constant value VAL and the entry block BB to a GOTO_EXPR
2110 statement, determine which of the outgoing edges will be taken out of the
2111 block. Return NULL if either edge may be taken. */
2114 find_taken_edge_computed_goto (basic_block bb, tree val)
2119 dest = label_to_block (val);
2122 e = find_edge (bb, dest);
2123 gcc_assert (e != NULL);
2129 /* Given a constant value VAL and the entry block BB to a COND_EXPR
2130 statement, determine which of the two edges will be taken out of the
2131 block. Return NULL if either edge may be taken. */
2134 find_taken_edge_cond_expr (basic_block bb, tree val)
2136 edge true_edge, false_edge;
2138 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
2140 gcc_assert (TREE_CODE (val) == INTEGER_CST);
2141 return (integer_zerop (val) ? false_edge : true_edge);
2144 /* Given an INTEGER_CST VAL and the entry block BB to a SWITCH_EXPR
2145 statement, determine which edge will be taken out of the block. Return
2146 NULL if any edge may be taken. */
2149 find_taken_edge_switch_expr (basic_block bb, tree val)
2151 tree switch_expr, taken_case;
2152 basic_block dest_bb;
2155 switch_expr = last_stmt (bb);
2156 taken_case = find_case_label_for_value (switch_expr, val);
2157 dest_bb = label_to_block (CASE_LABEL (taken_case));
2159 e = find_edge (bb, dest_bb);
2165 /* Return the CASE_LABEL_EXPR that SWITCH_EXPR will take for VAL.
2166 We can make optimal use here of the fact that the case labels are
2167 sorted: We can do a binary search for a case matching VAL. */
2170 find_case_label_for_value (tree switch_expr, tree val)
2172 tree vec = SWITCH_LABELS (switch_expr);
2173 size_t low, high, n = TREE_VEC_LENGTH (vec);
2174 tree default_case = TREE_VEC_ELT (vec, n - 1);
2176 for (low = -1, high = n - 1; high - low > 1; )
2178 size_t i = (high + low) / 2;
2179 tree t = TREE_VEC_ELT (vec, i);
2182 /* Cache the result of comparing CASE_LOW and val. */
2183 cmp = tree_int_cst_compare (CASE_LOW (t), val);
2190 if (CASE_HIGH (t) == NULL)
2192 /* A singe-valued case label. */
2198 /* A case range. We can only handle integer ranges. */
2199 if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
2204 return default_case;
2210 /*---------------------------------------------------------------------------
2212 ---------------------------------------------------------------------------*/
2214 /* Dump tree-specific information of block BB to file OUTF. */
2217 tree_dump_bb (basic_block bb, FILE *outf, int indent)
2219 dump_generic_bb (outf, bb, indent, TDF_VOPS|TDF_MEMSYMS);
2223 /* Dump a basic block on stderr. */
2226 debug_tree_bb (basic_block bb)
2228 dump_bb (bb, stderr, 0);
2232 /* Dump basic block with index N on stderr. */
2235 debug_tree_bb_n (int n)
2237 debug_tree_bb (BASIC_BLOCK (n));
2238 return BASIC_BLOCK (n);
2242 /* Dump the CFG on stderr.
2244 FLAGS are the same used by the tree dumping functions
2245 (see TDF_* in tree-pass.h). */
2248 debug_tree_cfg (int flags)
2250 dump_tree_cfg (stderr, flags);
2254 /* Dump the program showing basic block boundaries on the given FILE.
2256 FLAGS are the same used by the tree dumping functions (see TDF_* in
2260 dump_tree_cfg (FILE *file, int flags)
2262 if (flags & TDF_DETAILS)
2264 const char *funcname
2265 = lang_hooks.decl_printable_name (current_function_decl, 2);
2268 fprintf (file, ";; Function %s\n\n", funcname);
2269 fprintf (file, ";; \n%d basic blocks, %d edges, last basic block %d.\n\n",
2270 n_basic_blocks, n_edges, last_basic_block);
2272 brief_dump_cfg (file);
2273 fprintf (file, "\n");
2276 if (flags & TDF_STATS)
2277 dump_cfg_stats (file);
2279 dump_function_to_file (current_function_decl, file, flags | TDF_BLOCKS);
2283 /* Dump CFG statistics on FILE. */
2286 dump_cfg_stats (FILE *file)
2288 static long max_num_merged_labels = 0;
2289 unsigned long size, total = 0;
2292 const char * const fmt_str = "%-30s%-13s%12s\n";
2293 const char * const fmt_str_1 = "%-30s%13d%11lu%c\n";
2294 const char * const fmt_str_2 = "%-30s%13ld%11lu%c\n";
2295 const char * const fmt_str_3 = "%-43s%11lu%c\n";
2296 const char *funcname
2297 = lang_hooks.decl_printable_name (current_function_decl, 2);
2300 fprintf (file, "\nCFG Statistics for %s\n\n", funcname);
2302 fprintf (file, "---------------------------------------------------------\n");
2303 fprintf (file, fmt_str, "", " Number of ", "Memory");
2304 fprintf (file, fmt_str, "", " instances ", "used ");
2305 fprintf (file, "---------------------------------------------------------\n");
2307 size = n_basic_blocks * sizeof (struct basic_block_def);
2309 fprintf (file, fmt_str_1, "Basic blocks", n_basic_blocks,
2310 SCALE (size), LABEL (size));
2314 num_edges += EDGE_COUNT (bb->succs);
2315 size = num_edges * sizeof (struct edge_def);
2317 fprintf (file, fmt_str_2, "Edges", num_edges, SCALE (size), LABEL (size));
2319 fprintf (file, "---------------------------------------------------------\n");
2320 fprintf (file, fmt_str_3, "Total memory used by CFG data", SCALE (total),
2322 fprintf (file, "---------------------------------------------------------\n");
2323 fprintf (file, "\n");
2325 if (cfg_stats.num_merged_labels > max_num_merged_labels)
2326 max_num_merged_labels = cfg_stats.num_merged_labels;
2328 fprintf (file, "Coalesced label blocks: %ld (Max so far: %ld)\n",
2329 cfg_stats.num_merged_labels, max_num_merged_labels);
2331 fprintf (file, "\n");
2335 /* Dump CFG statistics on stderr. Keep extern so that it's always
2336 linked in the final executable. */
2339 debug_cfg_stats (void)
2341 dump_cfg_stats (stderr);
2345 /* Dump the flowgraph to a .vcg FILE. */
2348 tree_cfg2vcg (FILE *file)
2353 const char *funcname
2354 = lang_hooks.decl_printable_name (current_function_decl, 2);
2356 /* Write the file header. */
2357 fprintf (file, "graph: { title: \"%s\"\n", funcname);
2358 fprintf (file, "node: { title: \"ENTRY\" label: \"ENTRY\" }\n");
2359 fprintf (file, "node: { title: \"EXIT\" label: \"EXIT\" }\n");
2361 /* Write blocks and edges. */
2362 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
2364 fprintf (file, "edge: { sourcename: \"ENTRY\" targetname: \"%d\"",
2367 if (e->flags & EDGE_FAKE)
2368 fprintf (file, " linestyle: dotted priority: 10");
2370 fprintf (file, " linestyle: solid priority: 100");
2372 fprintf (file, " }\n");
2378 enum tree_code head_code, end_code;
2379 const char *head_name, *end_name;
2382 tree first = first_stmt (bb);
2383 tree last = last_stmt (bb);
2387 head_code = TREE_CODE (first);
2388 head_name = tree_code_name[head_code];
2389 head_line = get_lineno (first);
2392 head_name = "no-statement";
2396 end_code = TREE_CODE (last);
2397 end_name = tree_code_name[end_code];
2398 end_line = get_lineno (last);
2401 end_name = "no-statement";
2403 fprintf (file, "node: { title: \"%d\" label: \"#%d\\n%s (%d)\\n%s (%d)\"}\n",
2404 bb->index, bb->index, head_name, head_line, end_name,
2407 FOR_EACH_EDGE (e, ei, bb->succs)
2409 if (e->dest == EXIT_BLOCK_PTR)
2410 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"EXIT\"", bb->index);
2412 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"%d\"", bb->index, e->dest->index);
2414 if (e->flags & EDGE_FAKE)
2415 fprintf (file, " priority: 10 linestyle: dotted");
2417 fprintf (file, " priority: 100 linestyle: solid");
2419 fprintf (file, " }\n");
2422 if (bb->next_bb != EXIT_BLOCK_PTR)
2426 fputs ("}\n\n", file);
2431 /*---------------------------------------------------------------------------
2432 Miscellaneous helpers
2433 ---------------------------------------------------------------------------*/
2435 /* Return true if T represents a stmt that always transfers control. */
2438 is_ctrl_stmt (const_tree t)
2440 return (TREE_CODE (t) == COND_EXPR
2441 || TREE_CODE (t) == SWITCH_EXPR
2442 || TREE_CODE (t) == GOTO_EXPR
2443 || TREE_CODE (t) == RETURN_EXPR
2444 || TREE_CODE (t) == RESX_EXPR);
2448 /* Return true if T is a statement that may alter the flow of control
2449 (e.g., a call to a non-returning function). */
2452 is_ctrl_altering_stmt (const_tree t)
2457 call = get_call_expr_in (CONST_CAST_TREE (t));
2460 /* A non-pure/const CALL_EXPR alters flow control if the current
2461 function has nonlocal labels. */
2462 if (TREE_SIDE_EFFECTS (call) && current_function_has_nonlocal_label)
2465 /* A CALL_EXPR also alters control flow if it does not return. */
2466 if (call_expr_flags (call) & ECF_NORETURN)
2470 /* OpenMP directives alter control flow. */
2471 if (OMP_DIRECTIVE_P (t))
2474 /* If a statement can throw, it alters control flow. */
2475 return tree_can_throw_internal (t);
2479 /* Return true if T is a computed goto. */
2482 computed_goto_p (const_tree t)
2484 return (TREE_CODE (t) == GOTO_EXPR
2485 && TREE_CODE (GOTO_DESTINATION (t)) != LABEL_DECL);
2489 /* Return true if T is a simple local goto. */
2492 simple_goto_p (const_tree t)
2494 return (TREE_CODE (t) == GOTO_EXPR
2495 && TREE_CODE (GOTO_DESTINATION (t)) == LABEL_DECL);
2499 /* Return true if T can make an abnormal transfer of control flow.
2500 Transfers of control flow associated with EH are excluded. */
2503 tree_can_make_abnormal_goto (const_tree t)
2505 if (computed_goto_p (t))
2507 if (TREE_CODE (t) == GIMPLE_MODIFY_STMT)
2508 t = GIMPLE_STMT_OPERAND (t, 1);
2509 if (TREE_CODE (t) == WITH_SIZE_EXPR)
2510 t = TREE_OPERAND (t, 0);
2511 if (TREE_CODE (t) == CALL_EXPR)
2512 return TREE_SIDE_EFFECTS (t) && current_function_has_nonlocal_label;
2517 /* Return true if T should start a new basic block. PREV_T is the
2518 statement preceding T. It is used when T is a label or a case label.
2519 Labels should only start a new basic block if their previous statement
2520 wasn't a label. Otherwise, sequence of labels would generate
2521 unnecessary basic blocks that only contain a single label. */
2524 stmt_starts_bb_p (const_tree t, const_tree prev_t)
2529 /* LABEL_EXPRs start a new basic block only if the preceding
2530 statement wasn't a label of the same type. This prevents the
2531 creation of consecutive blocks that have nothing but a single
2533 if (TREE_CODE (t) == LABEL_EXPR)
2535 /* Nonlocal and computed GOTO targets always start a new block. */
2536 if (DECL_NONLOCAL (LABEL_EXPR_LABEL (t))
2537 || FORCED_LABEL (LABEL_EXPR_LABEL (t)))
2540 if (prev_t && TREE_CODE (prev_t) == LABEL_EXPR)
2542 if (DECL_NONLOCAL (LABEL_EXPR_LABEL (prev_t)))
2545 cfg_stats.num_merged_labels++;
2556 /* Return true if T should end a basic block. */
2559 stmt_ends_bb_p (const_tree t)
2561 return is_ctrl_stmt (t) || is_ctrl_altering_stmt (t);
2564 /* Remove block annotations and other datastructures. */
2567 delete_tree_cfg_annotations (void)
2570 block_stmt_iterator bsi;
2572 /* Remove annotations from every tree in the function. */
2574 for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
2576 tree stmt = bsi_stmt (bsi);
2577 ggc_free (stmt->base.ann);
2578 stmt->base.ann = NULL;
2580 label_to_block_map = NULL;
2584 /* Return the first statement in basic block BB. */
2587 first_stmt (basic_block bb)
2589 block_stmt_iterator i = bsi_start (bb);
2590 return !bsi_end_p (i) ? bsi_stmt (i) : NULL_TREE;
2593 /* Return the last statement in basic block BB. */
2596 last_stmt (basic_block bb)
2598 block_stmt_iterator b = bsi_last (bb);
2599 return !bsi_end_p (b) ? bsi_stmt (b) : NULL_TREE;
2602 /* Return the last statement of an otherwise empty block. Return NULL
2603 if the block is totally empty, or if it contains more than one
2607 last_and_only_stmt (basic_block bb)
2609 block_stmt_iterator i = bsi_last (bb);
2615 last = bsi_stmt (i);
2620 /* Empty statements should no longer appear in the instruction stream.
2621 Everything that might have appeared before should be deleted by
2622 remove_useless_stmts, and the optimizers should just bsi_remove
2623 instead of smashing with build_empty_stmt.
2625 Thus the only thing that should appear here in a block containing
2626 one executable statement is a label. */
2627 prev = bsi_stmt (i);
2628 if (TREE_CODE (prev) == LABEL_EXPR)
2635 /* Mark BB as the basic block holding statement T. */
2638 set_bb_for_stmt (tree t, basic_block bb)
2640 if (TREE_CODE (t) == PHI_NODE)
2642 else if (TREE_CODE (t) == STATEMENT_LIST)
2644 tree_stmt_iterator i;
2645 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
2646 set_bb_for_stmt (tsi_stmt (i), bb);
2650 stmt_ann_t ann = get_stmt_ann (t);
2653 /* If the statement is a label, add the label to block-to-labels map
2654 so that we can speed up edge creation for GOTO_EXPRs. */
2655 if (TREE_CODE (t) == LABEL_EXPR)
2659 t = LABEL_EXPR_LABEL (t);
2660 uid = LABEL_DECL_UID (t);
2663 unsigned old_len = VEC_length (basic_block, label_to_block_map);
2664 LABEL_DECL_UID (t) = uid = cfun->last_label_uid++;
2665 if (old_len <= (unsigned) uid)
2667 unsigned new_len = 3 * uid / 2;
2669 VEC_safe_grow_cleared (basic_block, gc, label_to_block_map,
2674 /* We're moving an existing label. Make sure that we've
2675 removed it from the old block. */
2677 || !VEC_index (basic_block, label_to_block_map, uid));
2678 VEC_replace (basic_block, label_to_block_map, uid, bb);
2683 /* Faster version of set_bb_for_stmt that assume that statement is being moved
2684 from one basic block to another.
2685 For BB splitting we can run into quadratic case, so performance is quite
2686 important and knowing that the tables are big enough, change_bb_for_stmt
2687 can inline as leaf function. */
2689 change_bb_for_stmt (tree t, basic_block bb)
2691 get_stmt_ann (t)->bb = bb;
2692 if (TREE_CODE (t) == LABEL_EXPR)
2693 VEC_replace (basic_block, label_to_block_map,
2694 LABEL_DECL_UID (LABEL_EXPR_LABEL (t)), bb);
2697 /* Finds iterator for STMT. */
2699 extern block_stmt_iterator
2700 bsi_for_stmt (tree stmt)
2702 block_stmt_iterator bsi;
2704 for (bsi = bsi_start (bb_for_stmt (stmt)); !bsi_end_p (bsi); bsi_next (&bsi))
2705 if (bsi_stmt (bsi) == stmt)
2711 /* Mark statement T as modified, and update it. */
2713 update_modified_stmts (tree t)
2715 if (!ssa_operands_active ())
2717 if (TREE_CODE (t) == STATEMENT_LIST)
2719 tree_stmt_iterator i;
2721 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
2723 stmt = tsi_stmt (i);
2724 update_stmt_if_modified (stmt);
2728 update_stmt_if_modified (t);
2731 /* Insert statement (or statement list) T before the statement
2732 pointed-to by iterator I. M specifies how to update iterator I
2733 after insertion (see enum bsi_iterator_update). */
2736 bsi_insert_before (block_stmt_iterator *i, tree t, enum bsi_iterator_update m)
2738 set_bb_for_stmt (t, i->bb);
2739 update_modified_stmts (t);
2740 tsi_link_before (&i->tsi, t, m);
2744 /* Insert statement (or statement list) T after the statement
2745 pointed-to by iterator I. M specifies how to update iterator I
2746 after insertion (see enum bsi_iterator_update). */
2749 bsi_insert_after (block_stmt_iterator *i, tree t, enum bsi_iterator_update m)
2751 set_bb_for_stmt (t, i->bb);
2752 update_modified_stmts (t);
2753 tsi_link_after (&i->tsi, t, m);
2757 /* Remove the statement pointed to by iterator I. The iterator is updated
2758 to the next statement.
2760 When REMOVE_EH_INFO is true we remove the statement pointed to by
2761 iterator I from the EH tables. Otherwise we do not modify the EH
2764 Generally, REMOVE_EH_INFO should be true when the statement is going to
2765 be removed from the IL and not reinserted elsewhere. */
2768 bsi_remove (block_stmt_iterator *i, bool remove_eh_info)
2770 tree t = bsi_stmt (*i);
2771 set_bb_for_stmt (t, NULL);
2772 delink_stmt_imm_use (t);
2773 tsi_delink (&i->tsi);
2774 mark_stmt_modified (t);
2777 remove_stmt_from_eh_region (t);
2778 gimple_remove_stmt_histograms (cfun, t);
2783 /* Move the statement at FROM so it comes right after the statement at TO. */
2786 bsi_move_after (block_stmt_iterator *from, block_stmt_iterator *to)
2788 tree stmt = bsi_stmt (*from);
2789 bsi_remove (from, false);
2790 /* We must have BSI_NEW_STMT here, as bsi_move_after is sometimes used to
2791 move statements to an empty block. */
2792 bsi_insert_after (to, stmt, BSI_NEW_STMT);
2796 /* Move the statement at FROM so it comes right before the statement at TO. */
2799 bsi_move_before (block_stmt_iterator *from, block_stmt_iterator *to)
2801 tree stmt = bsi_stmt (*from);
2802 bsi_remove (from, false);
2803 /* For consistency with bsi_move_after, it might be better to have
2804 BSI_NEW_STMT here; however, that breaks several places that expect
2805 that TO does not change. */
2806 bsi_insert_before (to, stmt, BSI_SAME_STMT);
2810 /* Move the statement at FROM to the end of basic block BB. */
2813 bsi_move_to_bb_end (block_stmt_iterator *from, basic_block bb)
2815 block_stmt_iterator last = bsi_last (bb);
2817 /* Have to check bsi_end_p because it could be an empty block. */
2818 if (!bsi_end_p (last) && is_ctrl_stmt (bsi_stmt (last)))
2819 bsi_move_before (from, &last);
2821 bsi_move_after (from, &last);
2825 /* Replace the contents of the statement pointed to by iterator BSI
2826 with STMT. If UPDATE_EH_INFO is true, the exception handling
2827 information of the original statement is moved to the new statement. */
2830 bsi_replace (const block_stmt_iterator *bsi, tree stmt, bool update_eh_info)
2833 tree orig_stmt = bsi_stmt (*bsi);
2835 if (stmt == orig_stmt)
2837 SET_EXPR_LOCUS (stmt, EXPR_LOCUS (orig_stmt));
2838 set_bb_for_stmt (stmt, bsi->bb);
2840 /* Preserve EH region information from the original statement, if
2841 requested by the caller. */
2844 eh_region = lookup_stmt_eh_region (orig_stmt);
2847 remove_stmt_from_eh_region (orig_stmt);
2848 add_stmt_to_eh_region (stmt, eh_region);
2852 gimple_duplicate_stmt_histograms (cfun, stmt, cfun, orig_stmt);
2853 gimple_remove_stmt_histograms (cfun, orig_stmt);
2854 delink_stmt_imm_use (orig_stmt);
2855 *bsi_stmt_ptr (*bsi) = stmt;
2856 mark_stmt_modified (stmt);
2857 update_modified_stmts (stmt);
2861 /* Insert the statement pointed-to by BSI into edge E. Every attempt
2862 is made to place the statement in an existing basic block, but
2863 sometimes that isn't possible. When it isn't possible, the edge is
2864 split and the statement is added to the new block.
2866 In all cases, the returned *BSI points to the correct location. The
2867 return value is true if insertion should be done after the location,
2868 or false if it should be done before the location. If new basic block
2869 has to be created, it is stored in *NEW_BB. */
2872 tree_find_edge_insert_loc (edge e, block_stmt_iterator *bsi,
2873 basic_block *new_bb)
2875 basic_block dest, src;
2881 /* If the destination has one predecessor which has no PHI nodes,
2882 insert there. Except for the exit block.
2884 The requirement for no PHI nodes could be relaxed. Basically we
2885 would have to examine the PHIs to prove that none of them used
2886 the value set by the statement we want to insert on E. That
2887 hardly seems worth the effort. */
2888 if (single_pred_p (dest)
2889 && ! phi_nodes (dest)
2890 && dest != EXIT_BLOCK_PTR)
2892 *bsi = bsi_start (dest);
2893 if (bsi_end_p (*bsi))
2896 /* Make sure we insert after any leading labels. */
2897 tmp = bsi_stmt (*bsi);
2898 while (TREE_CODE (tmp) == LABEL_EXPR)
2901 if (bsi_end_p (*bsi))
2903 tmp = bsi_stmt (*bsi);
2906 if (bsi_end_p (*bsi))
2908 *bsi = bsi_last (dest);
2915 /* If the source has one successor, the edge is not abnormal and
2916 the last statement does not end a basic block, insert there.
2917 Except for the entry block. */
2919 if ((e->flags & EDGE_ABNORMAL) == 0
2920 && single_succ_p (src)
2921 && src != ENTRY_BLOCK_PTR)
2923 *bsi = bsi_last (src);
2924 if (bsi_end_p (*bsi))
2927 tmp = bsi_stmt (*bsi);
2928 if (!stmt_ends_bb_p (tmp))
2931 /* Insert code just before returning the value. We may need to decompose
2932 the return in the case it contains non-trivial operand. */
2933 if (TREE_CODE (tmp) == RETURN_EXPR)
2935 tree op = TREE_OPERAND (tmp, 0);
2936 if (op && !is_gimple_val (op))
2938 gcc_assert (TREE_CODE (op) == GIMPLE_MODIFY_STMT);
2939 bsi_insert_before (bsi, op, BSI_NEW_STMT);
2940 TREE_OPERAND (tmp, 0) = GIMPLE_STMT_OPERAND (op, 0);
2947 /* Otherwise, create a new basic block, and split this edge. */
2948 dest = split_edge (e);
2951 e = single_pred_edge (dest);
2956 /* This routine will commit all pending edge insertions, creating any new
2957 basic blocks which are necessary. */
2960 bsi_commit_edge_inserts (void)
2966 bsi_commit_one_edge_insert (single_succ_edge (ENTRY_BLOCK_PTR), NULL);
2969 FOR_EACH_EDGE (e, ei, bb->succs)
2970 bsi_commit_one_edge_insert (e, NULL);
2974 /* Commit insertions pending at edge E. If a new block is created, set NEW_BB
2975 to this block, otherwise set it to NULL. */
2978 bsi_commit_one_edge_insert (edge e, basic_block *new_bb)
2982 if (PENDING_STMT (e))
2984 block_stmt_iterator bsi;
2985 tree stmt = PENDING_STMT (e);
2987 PENDING_STMT (e) = NULL_TREE;
2989 if (tree_find_edge_insert_loc (e, &bsi, new_bb))
2990 bsi_insert_after (&bsi, stmt, BSI_NEW_STMT);
2992 bsi_insert_before (&bsi, stmt, BSI_NEW_STMT);
2997 /* Add STMT to the pending list of edge E. No actual insertion is
2998 made until a call to bsi_commit_edge_inserts () is made. */
3001 bsi_insert_on_edge (edge e, tree stmt)
3003 append_to_statement_list (stmt, &PENDING_STMT (e));
3006 /* Similar to bsi_insert_on_edge+bsi_commit_edge_inserts. If a new
3007 block has to be created, it is returned. */
3010 bsi_insert_on_edge_immediate (edge e, tree stmt)
3012 block_stmt_iterator bsi;
3013 basic_block new_bb = NULL;
3015 gcc_assert (!PENDING_STMT (e));
3017 if (tree_find_edge_insert_loc (e, &bsi, &new_bb))
3018 bsi_insert_after (&bsi, stmt, BSI_NEW_STMT);
3020 bsi_insert_before (&bsi, stmt, BSI_NEW_STMT);
3025 /*---------------------------------------------------------------------------
3026 Tree specific functions for CFG manipulation
3027 ---------------------------------------------------------------------------*/
3029 /* Reinstall those PHI arguments queued in OLD_EDGE to NEW_EDGE. */
3032 reinstall_phi_args (edge new_edge, edge old_edge)
3036 if (!PENDING_STMT (old_edge))
3039 for (var = PENDING_STMT (old_edge), phi = phi_nodes (new_edge->dest);
3041 var = TREE_CHAIN (var), phi = PHI_CHAIN (phi))
3043 tree result = TREE_PURPOSE (var);
3044 tree arg = TREE_VALUE (var);
3046 gcc_assert (result == PHI_RESULT (phi));
3048 add_phi_arg (phi, arg, new_edge);
3051 PENDING_STMT (old_edge) = NULL;
3054 /* Returns the basic block after which the new basic block created
3055 by splitting edge EDGE_IN should be placed. Tries to keep the new block
3056 near its "logical" location. This is of most help to humans looking
3057 at debugging dumps. */
3060 split_edge_bb_loc (edge edge_in)
3062 basic_block dest = edge_in->dest;
3064 if (dest->prev_bb && find_edge (dest->prev_bb, dest))
3065 return edge_in->src;
3067 return dest->prev_bb;
3070 /* Split a (typically critical) edge EDGE_IN. Return the new block.
3071 Abort on abnormal edges. */
3074 tree_split_edge (edge edge_in)
3076 basic_block new_bb, after_bb, dest;
3079 /* Abnormal edges cannot be split. */
3080 gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
3082 dest = edge_in->dest;
3084 after_bb = split_edge_bb_loc (edge_in);
3086 new_bb = create_empty_bb (after_bb);
3087 new_bb->frequency = EDGE_FREQUENCY (edge_in);
3088 new_bb->count = edge_in->count;
3089 new_edge = make_edge (new_bb, dest, EDGE_FALLTHRU);
3090 new_edge->probability = REG_BR_PROB_BASE;
3091 new_edge->count = edge_in->count;
3093 e = redirect_edge_and_branch (edge_in, new_bb);
3094 gcc_assert (e == edge_in);
3095 reinstall_phi_args (new_edge, e);
3100 /* Callback for walk_tree, check that all elements with address taken are
3101 properly noticed as such. The DATA is an int* that is 1 if TP was seen
3102 inside a PHI node. */
3105 verify_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
3108 bool in_phi = (data != NULL);
3113 /* Check operand N for being valid GIMPLE and give error MSG if not. */
3114 #define CHECK_OP(N, MSG) \
3115 do { if (!is_gimple_val (TREE_OPERAND (t, N))) \
3116 { error (MSG); return TREE_OPERAND (t, N); }} while (0)
3118 switch (TREE_CODE (t))
3121 if (SSA_NAME_IN_FREE_LIST (t))
3123 error ("SSA name in freelist but still referenced");
3129 x = fold (ASSERT_EXPR_COND (t));
3130 if (x == boolean_false_node)
3132 error ("ASSERT_EXPR with an always-false condition");
3140 case GIMPLE_MODIFY_STMT:
3141 x = GIMPLE_STMT_OPERAND (t, 0);
3142 if (TREE_CODE (x) == BIT_FIELD_REF
3143 && is_gimple_reg (TREE_OPERAND (x, 0)))
3145 error ("GIMPLE register modified with BIT_FIELD_REF");
3154 bool old_side_effects;
3157 bool new_side_effects;
3159 /* ??? tree-ssa-alias.c may have overlooked dead PHI nodes, missing
3160 dead PHIs that take the address of something. But if the PHI
3161 result is dead, the fact that it takes the address of anything
3162 is irrelevant. Because we can not tell from here if a PHI result
3163 is dead, we just skip this check for PHIs altogether. This means
3164 we may be missing "valid" checks, but what can you do?
3165 This was PR19217. */
3169 old_invariant = TREE_INVARIANT (t);
3170 old_constant = TREE_CONSTANT (t);
3171 old_side_effects = TREE_SIDE_EFFECTS (t);
3173 recompute_tree_invariant_for_addr_expr (t);
3174 new_invariant = TREE_INVARIANT (t);
3175 new_side_effects = TREE_SIDE_EFFECTS (t);
3176 new_constant = TREE_CONSTANT (t);
3178 if (old_invariant != new_invariant)
3180 error ("invariant not recomputed when ADDR_EXPR changed");
3184 if (old_constant != new_constant)
3186 error ("constant not recomputed when ADDR_EXPR changed");
3189 if (old_side_effects != new_side_effects)
3191 error ("side effects not recomputed when ADDR_EXPR changed");
3195 /* Skip any references (they will be checked when we recurse down the
3196 tree) and ensure that any variable used as a prefix is marked
3198 for (x = TREE_OPERAND (t, 0);
3199 handled_component_p (x);
3200 x = TREE_OPERAND (x, 0))
3203 if (TREE_CODE (x) != VAR_DECL && TREE_CODE (x) != PARM_DECL)
3205 if (!TREE_ADDRESSABLE (x))
3207 error ("address taken, but ADDRESSABLE bit not set");
3211 /* Stop recursing and verifying invariant ADDR_EXPRs, they tend
3212 to become arbitrary complicated. */
3213 if (is_gimple_min_invariant (t))
3219 x = COND_EXPR_COND (t);
3220 if (!INTEGRAL_TYPE_P (TREE_TYPE (x)))
3222 error ("non-integral used in condition");
3225 if (!is_gimple_condexpr (x))
3227 error ("invalid conditional operand");
3234 case FIX_TRUNC_EXPR:
3239 case NON_LVALUE_EXPR:
3240 case TRUTH_NOT_EXPR:
3241 CHECK_OP (0, "invalid operand to unary operator");
3248 case ARRAY_RANGE_REF:
3250 case VIEW_CONVERT_EXPR:
3251 /* We have a nest of references. Verify that each of the operands
3252 that determine where to reference is either a constant or a variable,
3253 verify that the base is valid, and then show we've already checked
3255 while (handled_component_p (t))
3257 if (TREE_CODE (t) == COMPONENT_REF && TREE_OPERAND (t, 2))
3258 CHECK_OP (2, "invalid COMPONENT_REF offset operator");
3259 else if (TREE_CODE (t) == ARRAY_REF
3260 || TREE_CODE (t) == ARRAY_RANGE_REF)
3262 CHECK_OP (1, "invalid array index");
3263 if (TREE_OPERAND (t, 2))
3264 CHECK_OP (2, "invalid array lower bound");
3265 if (TREE_OPERAND (t, 3))
3266 CHECK_OP (3, "invalid array stride");
3268 else if (TREE_CODE (t) == BIT_FIELD_REF)
3270 if (!host_integerp (TREE_OPERAND (t, 1), 1)
3271 || !host_integerp (TREE_OPERAND (t, 2), 1))
3273 error ("invalid position or size operand to BIT_FIELD_REF");
3278 t = TREE_OPERAND (t, 0);
3281 if (!is_gimple_min_invariant (t) && !is_gimple_lvalue (t))
3283 error ("invalid reference prefix");
3290 /* PLUS_EXPR and MINUS_EXPR don't work on pointers, they should be done using
3291 POINTER_PLUS_EXPR. */
3292 if (POINTER_TYPE_P (TREE_TYPE (t)))
3294 error ("invalid operand to plus/minus, type is a pointer");
3297 CHECK_OP (0, "invalid operand to binary operator");
3298 CHECK_OP (1, "invalid operand to binary operator");
3301 case POINTER_PLUS_EXPR:
3302 /* Check to make sure the first operand is a pointer or reference type. */
3303 if (!POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 0))))
3305 error ("invalid operand to pointer plus, first operand is not a pointer");
3308 /* Check to make sure the second operand is an integer with type of
3310 if (!useless_type_conversion_p (sizetype,
3311 TREE_TYPE (TREE_OPERAND (t, 1))))
3313 error ("invalid operand to pointer plus, second operand is not an "
3314 "integer with type of sizetype.");
3324 case UNORDERED_EXPR:
3333 case TRUNC_DIV_EXPR:
3335 case FLOOR_DIV_EXPR:
3336 case ROUND_DIV_EXPR:
3337 case TRUNC_MOD_EXPR:
3339 case FLOOR_MOD_EXPR:
3340 case ROUND_MOD_EXPR:
3342 case EXACT_DIV_EXPR:
3352 CHECK_OP (0, "invalid operand to binary operator");
3353 CHECK_OP (1, "invalid operand to binary operator");
3357 if (TREE_CONSTANT (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
3369 /* Verifies if EXPR is a valid GIMPLE unary expression. Returns true
3370 if there is an error, otherwise false. */
3373 verify_gimple_unary_expr (const_tree expr)
3375 tree op = TREE_OPERAND (expr, 0);
3376 tree type = TREE_TYPE (expr);
3378 if (!is_gimple_val (op))
3380 error ("invalid operand in unary expression");
3384 /* For general unary expressions we have the operations type
3385 as the effective type the operation is carried out on. So all
3386 we need to require is that the operand is trivially convertible
3388 if (!useless_type_conversion_p (type, TREE_TYPE (op)))
3390 error ("type mismatch in unary expression");
3391 debug_generic_expr (type);
3392 debug_generic_expr (TREE_TYPE (op));
3399 /* Verifies if EXPR is a valid GIMPLE binary expression. Returns true
3400 if there is an error, otherwise false. */
3403 verify_gimple_binary_expr (const_tree expr)
3405 tree op0 = TREE_OPERAND (expr, 0);
3406 tree op1 = TREE_OPERAND (expr, 1);
3407 tree type = TREE_TYPE (expr);
3409 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3411 error ("invalid operands in binary expression");
3415 /* For general binary expressions we have the operations type
3416 as the effective type the operation is carried out on. So all
3417 we need to require is that both operands are trivially convertible
3419 if (!useless_type_conversion_p (type, TREE_TYPE (op0))
3420 || !useless_type_conversion_p (type, TREE_TYPE (op1)))
3422 error ("type mismatch in binary expression");
3423 debug_generic_stmt (type);
3424 debug_generic_stmt (TREE_TYPE (op0));
3425 debug_generic_stmt (TREE_TYPE (op1));
3432 /* Verify if EXPR is either a GIMPLE ID or a GIMPLE indirect reference.
3433 Returns true if there is an error, otherwise false. */
3436 verify_gimple_min_lval (tree expr)
3440 if (is_gimple_id (expr))
3443 if (TREE_CODE (expr) != INDIRECT_REF
3444 && TREE_CODE (expr) != ALIGN_INDIRECT_REF
3445 && TREE_CODE (expr) != MISALIGNED_INDIRECT_REF)
3447 error ("invalid expression for min lvalue");
3451 op = TREE_OPERAND (expr, 0);
3452 if (!is_gimple_val (op))
3454 error ("invalid operand in indirect reference");
3455 debug_generic_stmt (op);
3458 if (!useless_type_conversion_p (TREE_TYPE (expr),
3459 TREE_TYPE (TREE_TYPE (op))))
3461 error ("type mismatch in indirect reference");
3462 debug_generic_stmt (TREE_TYPE (expr));
3463 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3470 /* Verify if EXPR is a valid GIMPLE reference expression. Returns true
3471 if there is an error, otherwise false. */
3474 verify_gimple_reference (tree expr)
3476 while (handled_component_p (expr))
3478 tree op = TREE_OPERAND (expr, 0);
3480 if (TREE_CODE (expr) == ARRAY_REF
3481 || TREE_CODE (expr) == ARRAY_RANGE_REF)
3483 if (!is_gimple_val (TREE_OPERAND (expr, 1))
3484 || (TREE_OPERAND (expr, 2)
3485 && !is_gimple_val (TREE_OPERAND (expr, 2)))
3486 || (TREE_OPERAND (expr, 3)
3487 && !is_gimple_val (TREE_OPERAND (expr, 3))))
3489 error ("invalid operands to array reference");
3490 debug_generic_stmt (expr);
3495 /* Verify if the reference array element types are compatible. */
3496 if (TREE_CODE (expr) == ARRAY_REF
3497 && !useless_type_conversion_p (TREE_TYPE (expr),
3498 TREE_TYPE (TREE_TYPE (op))))
3500 error ("type mismatch in array reference");
3501 debug_generic_stmt (TREE_TYPE (expr));
3502 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3505 if (TREE_CODE (expr) == ARRAY_RANGE_REF
3506 && !useless_type_conversion_p (TREE_TYPE (TREE_TYPE (expr)),
3507 TREE_TYPE (TREE_TYPE (op))))
3509 error ("type mismatch in array range reference");
3510 debug_generic_stmt (TREE_TYPE (TREE_TYPE (expr)));
3511 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3515 if ((TREE_CODE (expr) == REALPART_EXPR
3516 || TREE_CODE (expr) == IMAGPART_EXPR)
3517 && !useless_type_conversion_p (TREE_TYPE (expr),
3518 TREE_TYPE (TREE_TYPE (op))))
3520 error ("type mismatch in real/imagpart reference");
3521 debug_generic_stmt (TREE_TYPE (expr));
3522 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3526 if (TREE_CODE (expr) == COMPONENT_REF
3527 && !useless_type_conversion_p (TREE_TYPE (expr),
3528 TREE_TYPE (TREE_OPERAND (expr, 1))))
3530 error ("type mismatch in component reference");
3531 debug_generic_stmt (TREE_TYPE (expr));
3532 debug_generic_stmt (TREE_TYPE (TREE_OPERAND (expr, 1)));
3536 /* For VIEW_CONVERT_EXPRs which are allowed here, too, there
3537 is nothing to verify. Gross mismatches at most invoke
3538 undefined behavior. */
3543 return verify_gimple_min_lval (expr);
3546 /* Returns true if there is one pointer type in TYPE_POINTER_TO (SRC_OBJ)
3547 list of pointer-to types that is trivially convertible to DEST. */
3550 one_pointer_to_useless_type_conversion_p (tree dest, tree src_obj)
3554 if (!TYPE_POINTER_TO (src_obj))
3557 for (src = TYPE_POINTER_TO (src_obj); src; src = TYPE_NEXT_PTR_TO (src))
3558 if (useless_type_conversion_p (dest, src))
3564 /* Verify the GIMPLE expression EXPR. Returns true if there is an
3565 error, otherwise false. */
3568 verify_gimple_expr (tree expr)
3570 tree type = TREE_TYPE (expr);
3572 if (is_gimple_val (expr))
3575 /* Special codes we cannot handle via their class. */
3576 switch (TREE_CODE (expr))
3581 tree op = TREE_OPERAND (expr, 0);
3582 if (!is_gimple_val (op))
3584 error ("invalid operand in conversion");
3588 /* Allow conversions between integral types and between
3590 if ((INTEGRAL_TYPE_P (type) && INTEGRAL_TYPE_P (TREE_TYPE (op)))
3591 || (POINTER_TYPE_P (type) && POINTER_TYPE_P (TREE_TYPE (op))))
3594 /* Allow conversions between integral types and pointers only if
3595 there is no sign or zero extension involved. */
3596 if (((POINTER_TYPE_P (type) && INTEGRAL_TYPE_P (TREE_TYPE (op)))
3597 || (POINTER_TYPE_P (TREE_TYPE (op)) && INTEGRAL_TYPE_P (type)))
3598 && TYPE_PRECISION (type) == TYPE_PRECISION (TREE_TYPE (op)))
3601 /* Allow conversion from integer to offset type and vice versa. */
3602 if ((TREE_CODE (type) == OFFSET_TYPE
3603 && TREE_CODE (TREE_TYPE (op)) == INTEGER_TYPE)
3604 || (TREE_CODE (type) == INTEGER_TYPE
3605 && TREE_CODE (TREE_TYPE (op)) == OFFSET_TYPE))
3608 /* Otherwise assert we are converting between types of the
3610 if (TREE_CODE (type) != TREE_CODE (TREE_TYPE (op)))
3612 error ("invalid types in nop conversion");
3613 debug_generic_expr (type);
3614 debug_generic_expr (TREE_TYPE (op));
3623 tree op = TREE_OPERAND (expr, 0);
3624 if (!is_gimple_val (op))
3626 error ("invalid operand in int to float conversion");
3629 if (!INTEGRAL_TYPE_P (TREE_TYPE (op))
3630 || !SCALAR_FLOAT_TYPE_P (type))
3632 error ("invalid types in conversion to floating point");
3633 debug_generic_expr (type);
3634 debug_generic_expr (TREE_TYPE (op));
3640 case FIX_TRUNC_EXPR:
3642 tree op = TREE_OPERAND (expr, 0);
3643 if (!is_gimple_val (op))
3645 error ("invalid operand in float to int conversion");
3648 if (!INTEGRAL_TYPE_P (type)
3649 || !SCALAR_FLOAT_TYPE_P (TREE_TYPE (op)))
3651 error ("invalid types in conversion to integer");
3652 debug_generic_expr (type);
3653 debug_generic_expr (TREE_TYPE (op));
3661 tree op0 = TREE_OPERAND (expr, 0);
3662 tree op1 = TREE_OPERAND (expr, 1);
3663 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3665 error ("invalid operands in complex expression");
3668 if (!TREE_CODE (type) == COMPLEX_TYPE
3669 || !(TREE_CODE (TREE_TYPE (op0)) == INTEGER_TYPE
3670 || SCALAR_FLOAT_TYPE_P (TREE_TYPE (op0)))
3671 || !(TREE_CODE (TREE_TYPE (op1)) == INTEGER_TYPE
3672 || SCALAR_FLOAT_TYPE_P (TREE_TYPE (op1)))
3673 || !useless_type_conversion_p (TREE_TYPE (type),
3675 || !useless_type_conversion_p (TREE_TYPE (type),
3678 error ("type mismatch in complex expression");
3679 debug_generic_stmt (TREE_TYPE (expr));
3680 debug_generic_stmt (TREE_TYPE (op0));
3681 debug_generic_stmt (TREE_TYPE (op1));
3689 /* This is used like COMPLEX_EXPR but for vectors. */
3690 if (TREE_CODE (type) != VECTOR_TYPE)
3692 error ("constructor not allowed for non-vector types");
3693 debug_generic_stmt (type);
3696 /* FIXME: verify constructor arguments. */
3705 tree op0 = TREE_OPERAND (expr, 0);
3706 tree op1 = TREE_OPERAND (expr, 1);
3707 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3709 error ("invalid operands in shift expression");
3712 if (!TREE_CODE (TREE_TYPE (op1)) == INTEGER_TYPE
3713 || !useless_type_conversion_p (type, TREE_TYPE (op0)))
3715 error ("type mismatch in shift expression");
3716 debug_generic_stmt (TREE_TYPE (expr));
3717 debug_generic_stmt (TREE_TYPE (op0));
3718 debug_generic_stmt (TREE_TYPE (op1));
3727 tree op0 = TREE_OPERAND (expr, 0);
3728 tree op1 = TREE_OPERAND (expr, 1);
3729 if (POINTER_TYPE_P (type)
3730 || POINTER_TYPE_P (TREE_TYPE (op0))
3731 || POINTER_TYPE_P (TREE_TYPE (op1)))
3733 error ("invalid (pointer) operands to plus/minus");
3736 /* Continue with generic binary expression handling. */
3740 case POINTER_PLUS_EXPR:
3742 tree op0 = TREE_OPERAND (expr, 0);
3743 tree op1 = TREE_OPERAND (expr, 1);
3744 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3746 error ("invalid operands in pointer plus expression");
3749 if (!POINTER_TYPE_P (TREE_TYPE (op0))
3750 || !useless_type_conversion_p (type, TREE_TYPE (op0))
3751 || !useless_type_conversion_p (sizetype, TREE_TYPE (op1)))
3753 error ("type mismatch in pointer plus expression");
3754 debug_generic_stmt (type);
3755 debug_generic_stmt (TREE_TYPE (op0));
3756 debug_generic_stmt (TREE_TYPE (op1));
3764 tree op0 = TREE_OPERAND (expr, 0);
3765 tree op1 = TREE_OPERAND (expr, 1);
3766 tree op2 = TREE_OPERAND (expr, 2);
3767 if ((!is_gimple_val (op1)
3768 && TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3769 || (!is_gimple_val (op2)
3770 && TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE))
3772 error ("invalid operands in conditional expression");
3775 if (!INTEGRAL_TYPE_P (TREE_TYPE (op0))
3776 || (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE
3777 && !useless_type_conversion_p (type, TREE_TYPE (op1)))
3778 || (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE
3779 && !useless_type_conversion_p (type, TREE_TYPE (op2))))
3781 error ("type mismatch in conditional expression");
3782 debug_generic_stmt (type);
3783 debug_generic_stmt (TREE_TYPE (op0));
3784 debug_generic_stmt (TREE_TYPE (op1));
3785 debug_generic_stmt (TREE_TYPE (op2));
3788 return verify_gimple_expr (op0);
3793 tree op = TREE_OPERAND (expr, 0);
3794 if (!is_gimple_addressable (op))
3796 error ("invalid operand in unary expression");
3799 if (!one_pointer_to_useless_type_conversion_p (type, TREE_TYPE (op))
3800 /* FIXME: a longstanding wart, &a == &a[0]. */
3801 && (TREE_CODE (TREE_TYPE (op)) != ARRAY_TYPE
3802 || !one_pointer_to_useless_type_conversion_p (type,
3803 TREE_TYPE (TREE_TYPE (op)))))
3805 error ("type mismatch in address expression");
3806 debug_generic_stmt (TREE_TYPE (expr));
3807 debug_generic_stmt (TYPE_POINTER_TO (TREE_TYPE (op)));
3811 return verify_gimple_reference (op);
3814 case TRUTH_ANDIF_EXPR:
3815 case TRUTH_ORIF_EXPR:
3816 case TRUTH_AND_EXPR:
3818 case TRUTH_XOR_EXPR:
3820 tree op0 = TREE_OPERAND (expr, 0);
3821 tree op1 = TREE_OPERAND (expr, 1);
3823 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3825 error ("invalid operands in truth expression");
3829 /* We allow any kind of integral typed argument and result. */
3830 if (!INTEGRAL_TYPE_P (TREE_TYPE (op0))
3831 || !INTEGRAL_TYPE_P (TREE_TYPE (op1))
3832 || !INTEGRAL_TYPE_P (type))
3834 error ("type mismatch in binary truth expression");
3835 debug_generic_stmt (type);
3836 debug_generic_stmt (TREE_TYPE (op0));
3837 debug_generic_stmt (TREE_TYPE (op1));
3844 case TRUTH_NOT_EXPR:
3846 tree op = TREE_OPERAND (expr, 0);
3848 if (!is_gimple_val (op))
3850 error ("invalid operand in unary not");
3854 /* For TRUTH_NOT_EXPR we can have any kind of integral
3855 typed arguments and results. */
3856 if (!INTEGRAL_TYPE_P (TREE_TYPE (op))
3857 || !INTEGRAL_TYPE_P (type))
3859 error ("type mismatch in not expression");
3860 debug_generic_expr (TREE_TYPE (expr));
3861 debug_generic_expr (TREE_TYPE (op));
3869 /* FIXME. The C frontend passes unpromoted arguments in case it
3870 didn't see a function declaration before the call. */
3880 /* Generic handling via classes. */
3881 switch (TREE_CODE_CLASS (TREE_CODE (expr)))
3884 return verify_gimple_unary_expr (expr);
3887 return verify_gimple_binary_expr (expr);
3890 return verify_gimple_reference (expr);
3892 case tcc_comparison:
3894 tree op0 = TREE_OPERAND (expr, 0);
3895 tree op1 = TREE_OPERAND (expr, 1);
3896 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3898 error ("invalid operands in comparison expression");
3901 /* For comparisons we do not have the operations type as the
3902 effective type the comparison is carried out in. Instead
3903 we require that either the first operand is trivially
3904 convertible into the second, or the other way around.
3905 The resulting type of a comparison may be any integral type.
3906 Because we special-case pointers to void we allow
3907 comparisons of pointers with the same mode as well. */
3908 if ((!useless_type_conversion_p (TREE_TYPE (op0), TREE_TYPE (op1))
3909 && !useless_type_conversion_p (TREE_TYPE (op1), TREE_TYPE (op0))
3910 && (!POINTER_TYPE_P (TREE_TYPE (op0))
3911 || !POINTER_TYPE_P (TREE_TYPE (op1))
3912 || TYPE_MODE (TREE_TYPE (op0)) != TYPE_MODE (TREE_TYPE (op1))))
3913 || !INTEGRAL_TYPE_P (type))
3915 error ("type mismatch in comparison expression");
3916 debug_generic_stmt (TREE_TYPE (expr));
3917 debug_generic_stmt (TREE_TYPE (op0));
3918 debug_generic_stmt (TREE_TYPE (op1));
3931 /* Verify the GIMPLE assignment statement STMT. Returns true if there
3932 is an error, otherwise false. */
3935 verify_gimple_modify_stmt (const_tree stmt)
3937 tree lhs = GIMPLE_STMT_OPERAND (stmt, 0);
3938 tree rhs = GIMPLE_STMT_OPERAND (stmt, 1);
3940 gcc_assert (TREE_CODE (stmt) == GIMPLE_MODIFY_STMT);
3942 if (!useless_type_conversion_p (TREE_TYPE (lhs),
3945 error ("non-trivial conversion at assignment");
3946 debug_generic_expr (TREE_TYPE (lhs));
3947 debug_generic_expr (TREE_TYPE (rhs));
3951 /* Loads/stores from/to a variable are ok. */
3952 if ((is_gimple_val (lhs)
3953 && is_gimple_variable (rhs))
3954 || (is_gimple_val (rhs)
3955 && is_gimple_variable (lhs)))
3958 /* Aggregate copies are ok. */
3959 if (!is_gimple_reg_type (TREE_TYPE (lhs))
3960 && !is_gimple_reg_type (TREE_TYPE (rhs)))
3963 /* We might get 'loads' from a parameter which is not a gimple value. */
3964 if (TREE_CODE (rhs) == PARM_DECL)
3965 return verify_gimple_expr (lhs);
3967 if (!is_gimple_variable (lhs)
3968 && verify_gimple_expr (lhs))
3971 if (!is_gimple_variable (rhs)
3972 && verify_gimple_expr (rhs))
3978 /* Verify the GIMPLE statement STMT. Returns true if there is an
3979 error, otherwise false. */
3982 verify_gimple_stmt (tree stmt)
3984 if (!is_gimple_stmt (stmt))
3986 error ("is not a valid GIMPLE statement");
3990 if (OMP_DIRECTIVE_P (stmt))
3992 /* OpenMP directives are validated by the FE and never operated
3993 on by the optimizers. Furthermore, OMP_FOR may contain
3994 non-gimple expressions when the main index variable has had
3995 its address taken. This does not affect the loop itself
3996 because the header of an OMP_FOR is merely used to determine
3997 how to setup the parallel iteration. */
4001 switch (TREE_CODE (stmt))
4003 case GIMPLE_MODIFY_STMT:
4004 return verify_gimple_modify_stmt (stmt);
4011 if (!is_gimple_val (TREE_OPERAND (stmt, 0)))
4013 error ("invalid operand to switch statement");
4014 debug_generic_expr (TREE_OPERAND (stmt, 0));
4020 tree op = TREE_OPERAND (stmt, 0);
4022 if (TREE_CODE (TREE_TYPE (stmt)) != VOID_TYPE)
4024 error ("type error in return expression");
4029 || TREE_CODE (op) == RESULT_DECL)
4032 return verify_gimple_modify_stmt (op);
4037 return verify_gimple_expr (stmt);
4040 case CHANGE_DYNAMIC_TYPE_EXPR:
4049 /* Verify the GIMPLE statements inside the statement list STMTS.
4050 Returns true if there were any errors. */
4053 verify_gimple_2 (tree stmts)
4055 tree_stmt_iterator tsi;
4058 for (tsi = tsi_start (stmts); !tsi_end_p (tsi); tsi_next (&tsi))
4060 tree stmt = tsi_stmt (tsi);
4062 switch (TREE_CODE (stmt))
4065 err |= verify_gimple_2 (BIND_EXPR_BODY (stmt));
4068 case TRY_CATCH_EXPR:
4069 case TRY_FINALLY_EXPR:
4070 err |= verify_gimple_2 (TREE_OPERAND (stmt, 0));
4071 err |= verify_gimple_2 (TREE_OPERAND (stmt, 1));
4075 err |= verify_gimple_2 (CATCH_BODY (stmt));
4078 case EH_FILTER_EXPR:
4079 err |= verify_gimple_2 (EH_FILTER_FAILURE (stmt));
4084 bool err2 = verify_gimple_stmt (stmt);
4086 debug_generic_expr (stmt);
4096 /* Verify the GIMPLE statements inside the statement list STMTS. */
4099 verify_gimple_1 (tree stmts)
4101 if (verify_gimple_2 (stmts))
4102 internal_error ("verify_gimple failed");
4105 /* Verify the GIMPLE statements inside the current function. */
4108 verify_gimple (void)
4110 verify_gimple_1 (BIND_EXPR_BODY (DECL_SAVED_TREE (cfun->decl)));
4113 /* Verify STMT, return true if STMT is not in GIMPLE form.
4114 TODO: Implement type checking. */
4117 verify_stmt (tree stmt, bool last_in_block)
4121 if (OMP_DIRECTIVE_P (stmt))
4123 /* OpenMP directives are validated by the FE and never operated
4124 on by the optimizers. Furthermore, OMP_FOR may contain
4125 non-gimple expressions when the main index variable has had
4126 its address taken. This does not affect the loop itself
4127 because the header of an OMP_FOR is merely used to determine
4128 how to setup the parallel iteration. */
4132 if (!is_gimple_stmt (stmt))
4134 error ("is not a valid GIMPLE statement");
4138 addr = walk_tree (&stmt, verify_expr, NULL, NULL);
4141 debug_generic_stmt (addr);
4145 /* If the statement is marked as part of an EH region, then it is
4146 expected that the statement could throw. Verify that when we
4147 have optimizations that simplify statements such that we prove
4148 that they cannot throw, that we update other data structures
4150 if (lookup_stmt_eh_region (stmt) >= 0)
4152 if (!tree_could_throw_p (stmt))
4154 error ("statement marked for throw, but doesn%'t");
4157 if (!last_in_block && tree_can_throw_internal (stmt))
4159 error ("statement marked for throw in middle of block");
4167 debug_generic_stmt (stmt);
4172 /* Return true when the T can be shared. */
4175 tree_node_can_be_shared (tree t)
4177 if (IS_TYPE_OR_DECL_P (t)
4178 || is_gimple_min_invariant (t)
4179 || TREE_CODE (t) == SSA_NAME
4180 || t == error_mark_node
4181 || TREE_CODE (t) == IDENTIFIER_NODE)
4184 if (TREE_CODE (t) == CASE_LABEL_EXPR)
4187 while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4188 && is_gimple_min_invariant (TREE_OPERAND (t, 1)))
4189 || TREE_CODE (t) == COMPONENT_REF
4190 || TREE_CODE (t) == REALPART_EXPR
4191 || TREE_CODE (t) == IMAGPART_EXPR)
4192 t = TREE_OPERAND (t, 0);
4201 /* Called via walk_trees. Verify tree sharing. */
4204 verify_node_sharing (tree * tp, int *walk_subtrees, void *data)
4206 struct pointer_set_t *visited = (struct pointer_set_t *) data;
4208 if (tree_node_can_be_shared (*tp))
4210 *walk_subtrees = false;
4214 if (pointer_set_insert (visited, *tp))
4221 /* Helper function for verify_gimple_tuples. */
4224 verify_gimple_tuples_1 (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
4225 void *data ATTRIBUTE_UNUSED)
4227 switch (TREE_CODE (*tp))
4230 error ("unexpected non-tuple");
4240 /* Verify that there are no trees that should have been converted to
4241 gimple tuples. Return true if T contains a node that should have
4242 been converted to a gimple tuple, but hasn't. */
4245 verify_gimple_tuples (tree t)
4247 return walk_tree (&t, verify_gimple_tuples_1, NULL, NULL) != NULL;
4250 static bool eh_error_found;
4252 verify_eh_throw_stmt_node (void **slot, void *data)
4254 struct throw_stmt_node *node = (struct throw_stmt_node *)*slot;
4255 struct pointer_set_t *visited = (struct pointer_set_t *) data;
4257 if (!pointer_set_contains (visited, node->stmt))
4259 error ("Dead STMT in EH table");
4260 debug_generic_stmt (node->stmt);
4261 eh_error_found = true;
4266 /* Verify the GIMPLE statement chain. */
4272 block_stmt_iterator bsi;
4274 struct pointer_set_t *visited, *visited_stmts;
4277 timevar_push (TV_TREE_STMT_VERIFY);
4278 visited = pointer_set_create ();
4279 visited_stmts = pointer_set_create ();
4286 for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
4288 int phi_num_args = PHI_NUM_ARGS (phi);
4290 pointer_set_insert (visited_stmts, phi);
4291 if (bb_for_stmt (phi) != bb)
4293 error ("bb_for_stmt (phi) is set to a wrong basic block");
4297 for (i = 0; i < phi_num_args; i++)
4299 tree t = PHI_ARG_DEF (phi, i);
4304 error ("missing PHI def");
4305 debug_generic_stmt (phi);
4309 /* Addressable variables do have SSA_NAMEs but they
4310 are not considered gimple values. */
4311 else if (TREE_CODE (t) != SSA_NAME
4312 && TREE_CODE (t) != FUNCTION_DECL
4313 && !is_gimple_val (t))
4315 error ("PHI def is not a GIMPLE value");
4316 debug_generic_stmt (phi);
4317 debug_generic_stmt (t);
4321 addr = walk_tree (&t, verify_expr, (void *) 1, NULL);
4324 debug_generic_stmt (addr);
4328 addr = walk_tree (&t, verify_node_sharing, visited, NULL);
4331 error ("incorrect sharing of tree nodes");
4332 debug_generic_stmt (phi);
4333 debug_generic_stmt (addr);
4339 for (bsi = bsi_start (bb); !bsi_end_p (bsi); )
4341 tree stmt = bsi_stmt (bsi);
4343 pointer_set_insert (visited_stmts, stmt);
4344 err |= verify_gimple_tuples (stmt);
4346 if (bb_for_stmt (stmt) != bb)
4348 error ("bb_for_stmt (stmt) is set to a wrong basic block");
4353 err |= verify_stmt (stmt, bsi_end_p (bsi));
4354 addr = walk_tree (&stmt, verify_node_sharing, visited, NULL);
4357 error ("incorrect sharing of tree nodes");
4358 debug_generic_stmt (stmt);
4359 debug_generic_stmt (addr);
4364 eh_error_found = false;
4365 if (get_eh_throw_stmt_table (cfun))
4366 htab_traverse (get_eh_throw_stmt_table (cfun),
4367 verify_eh_throw_stmt_node,
4370 if (err | eh_error_found)
4371 internal_error ("verify_stmts failed");
4373 pointer_set_destroy (visited);
4374 pointer_set_destroy (visited_stmts);
4375 verify_histograms ();
4376 timevar_pop (TV_TREE_STMT_VERIFY);
4380 /* Verifies that the flow information is OK. */
4383 tree_verify_flow_info (void)
4387 block_stmt_iterator bsi;
4392 if (ENTRY_BLOCK_PTR->il.tree)
4394 error ("ENTRY_BLOCK has IL associated with it");
4398 if (EXIT_BLOCK_PTR->il.tree)
4400 error ("EXIT_BLOCK has IL associated with it");
4404 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4405 if (e->flags & EDGE_FALLTHRU)
4407 error ("fallthru to exit from bb %d", e->src->index);
4413 bool found_ctrl_stmt = false;
4417 /* Skip labels on the start of basic block. */
4418 for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
4420 tree prev_stmt = stmt;
4422 stmt = bsi_stmt (bsi);
4424 if (TREE_CODE (stmt) != LABEL_EXPR)
4427 if (prev_stmt && DECL_NONLOCAL (LABEL_EXPR_LABEL (stmt)))
4429 error ("nonlocal label ");
4430 print_generic_expr (stderr, LABEL_EXPR_LABEL (stmt), 0);
4431 fprintf (stderr, " is not first in a sequence of labels in bb %d",
4436 if (label_to_block (LABEL_EXPR_LABEL (stmt)) != bb)
4439 print_generic_expr (stderr, LABEL_EXPR_LABEL (stmt), 0);
4440 fprintf (stderr, " to block does not match in bb %d",
4445 if (decl_function_context (LABEL_EXPR_LABEL (stmt))
4446 != current_function_decl)
4449 print_generic_expr (stderr, LABEL_EXPR_LABEL (stmt), 0);
4450 fprintf (stderr, " has incorrect context in bb %d",
4456 /* Verify that body of basic block BB is free of control flow. */
4457 for (; !bsi_end_p (bsi); bsi_next (&bsi))
4459 tree stmt = bsi_stmt (bsi);
4461 if (found_ctrl_stmt)
4463 error ("control flow in the middle of basic block %d",
4468 if (stmt_ends_bb_p (stmt))
4469 found_ctrl_stmt = true;
4471 if (TREE_CODE (stmt) == LABEL_EXPR)
4474 print_generic_expr (stderr, LABEL_EXPR_LABEL (stmt), 0);
4475 fprintf (stderr, " in the middle of basic block %d", bb->index);
4480 bsi = bsi_last (bb);
4481 if (bsi_end_p (bsi))
4484 stmt = bsi_stmt (bsi);
4486 err |= verify_eh_edges (stmt);
4488 if (is_ctrl_stmt (stmt))
4490 FOR_EACH_EDGE (e, ei, bb->succs)
4491 if (e->flags & EDGE_FALLTHRU)
4493 error ("fallthru edge after a control statement in bb %d",
4499 if (TREE_CODE (stmt) != COND_EXPR)
4501 /* Verify that there are no edges with EDGE_TRUE/FALSE_FLAG set
4502 after anything else but if statement. */
4503 FOR_EACH_EDGE (e, ei, bb->succs)
4504 if (e->flags & (EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))
4506 error ("true/false edge after a non-COND_EXPR in bb %d",
4512 switch (TREE_CODE (stmt))
4519 if (COND_EXPR_THEN (stmt) != NULL_TREE
4520 || COND_EXPR_ELSE (stmt) != NULL_TREE)
4522 error ("COND_EXPR with code in branches at the end of bb %d",
4527 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
4529 if (!true_edge || !false_edge
4530 || !(true_edge->flags & EDGE_TRUE_VALUE)
4531 || !(false_edge->flags & EDGE_FALSE_VALUE)
4532 || (true_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4533 || (false_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4534 || EDGE_COUNT (bb->succs) >= 3)
4536 error ("wrong outgoing edge flags at end of bb %d",
4544 if (simple_goto_p (stmt))
4546 error ("explicit goto at end of bb %d", bb->index);
4551 /* FIXME. We should double check that the labels in the
4552 destination blocks have their address taken. */
4553 FOR_EACH_EDGE (e, ei, bb->succs)
4554 if ((e->flags & (EDGE_FALLTHRU | EDGE_TRUE_VALUE
4555 | EDGE_FALSE_VALUE))
4556 || !(e->flags & EDGE_ABNORMAL))
4558 error ("wrong outgoing edge flags at end of bb %d",
4566 if (!single_succ_p (bb)
4567 || (single_succ_edge (bb)->flags
4568 & (EDGE_FALLTHRU | EDGE_ABNORMAL
4569 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4571 error ("wrong outgoing edge flags at end of bb %d", bb->index);
4574 if (single_succ (bb) != EXIT_BLOCK_PTR)
4576 error ("return edge does not point to exit in bb %d",
4589 vec = SWITCH_LABELS (stmt);
4590 n = TREE_VEC_LENGTH (vec);
4592 /* Mark all the destination basic blocks. */
4593 for (i = 0; i < n; ++i)
4595 tree lab = CASE_LABEL (TREE_VEC_ELT (vec, i));
4596 basic_block label_bb = label_to_block (lab);
4598 gcc_assert (!label_bb->aux || label_bb->aux == (void *)1);
4599 label_bb->aux = (void *)1;
4602 /* Verify that the case labels are sorted. */
4603 prev = TREE_VEC_ELT (vec, 0);
4604 for (i = 1; i < n - 1; ++i)
4606 tree c = TREE_VEC_ELT (vec, i);
4609 error ("found default case not at end of case vector");
4613 if (! tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c)))
4615 error ("case labels not sorted: ");
4616 print_generic_expr (stderr, prev, 0);
4617 fprintf (stderr," is greater than ");
4618 print_generic_expr (stderr, c, 0);
4619 fprintf (stderr," but comes before it.\n");
4624 if (CASE_LOW (TREE_VEC_ELT (vec, n - 1)))
4626 error ("no default case found at end of case vector");
4630 FOR_EACH_EDGE (e, ei, bb->succs)
4634 error ("extra outgoing edge %d->%d",
4635 bb->index, e->dest->index);
4638 e->dest->aux = (void *)2;
4639 if ((e->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL
4640 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4642 error ("wrong outgoing edge flags at end of bb %d",
4648 /* Check that we have all of them. */
4649 for (i = 0; i < n; ++i)
4651 tree lab = CASE_LABEL (TREE_VEC_ELT (vec, i));
4652 basic_block label_bb = label_to_block (lab);
4654 if (label_bb->aux != (void *)2)
4656 error ("missing edge %i->%i",
4657 bb->index, label_bb->index);
4662 FOR_EACH_EDGE (e, ei, bb->succs)
4663 e->dest->aux = (void *)0;
4670 if (dom_info_state (CDI_DOMINATORS) >= DOM_NO_FAST_QUERY)
4671 verify_dominators (CDI_DOMINATORS);
4677 /* Updates phi nodes after creating a forwarder block joined
4678 by edge FALLTHRU. */
4681 tree_make_forwarder_block (edge fallthru)
4685 basic_block dummy, bb;
4686 tree phi, new_phi, var;
4688 dummy = fallthru->src;
4689 bb = fallthru->dest;
4691 if (single_pred_p (bb))
4694 /* If we redirected a branch we must create new PHI nodes at the
4696 for (phi = phi_nodes (dummy); phi; phi = PHI_CHAIN (phi))
4698 var = PHI_RESULT (phi);
4699 new_phi = create_phi_node (var, bb);
4700 SSA_NAME_DEF_STMT (var) = new_phi;
4701 SET_PHI_RESULT (phi, make_ssa_name (SSA_NAME_VAR (var), phi));
4702 add_phi_arg (new_phi, PHI_RESULT (phi), fallthru);
4705 /* Ensure that the PHI node chain is in the same order. */
4706 set_phi_nodes (bb, phi_reverse (phi_nodes (bb)));
4708 /* Add the arguments we have stored on edges. */
4709 FOR_EACH_EDGE (e, ei, bb->preds)
4714 flush_pending_stmts (e);
4719 /* Return a non-special label in the head of basic block BLOCK.
4720 Create one if it doesn't exist. */
4723 tree_block_label (basic_block bb)
4725 block_stmt_iterator i, s = bsi_start (bb);
4729 for (i = s; !bsi_end_p (i); first = false, bsi_next (&i))
4731 stmt = bsi_stmt (i);
4732 if (TREE_CODE (stmt) != LABEL_EXPR)
4734 label = LABEL_EXPR_LABEL (stmt);
4735 if (!DECL_NONLOCAL (label))
4738 bsi_move_before (&i, &s);
4743 label = create_artificial_label ();
4744 stmt = build1 (LABEL_EXPR, void_type_node, label);
4745 bsi_insert_before (&s, stmt, BSI_NEW_STMT);
4750 /* Attempt to perform edge redirection by replacing a possibly complex
4751 jump instruction by a goto or by removing the jump completely.
4752 This can apply only if all edges now point to the same block. The
4753 parameters and return values are equivalent to
4754 redirect_edge_and_branch. */
4757 tree_try_redirect_by_replacing_jump (edge e, basic_block target)
4759 basic_block src = e->src;
4760 block_stmt_iterator b;
4763 /* We can replace or remove a complex jump only when we have exactly
4765 if (EDGE_COUNT (src->succs) != 2
4766 /* Verify that all targets will be TARGET. Specifically, the
4767 edge that is not E must also go to TARGET. */
4768 || EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)
4774 stmt = bsi_stmt (b);
4776 if (TREE_CODE (stmt) == COND_EXPR
4777 || TREE_CODE (stmt) == SWITCH_EXPR)
4779 bsi_remove (&b, true);
4780 e = ssa_redirect_edge (e, target);
4781 e->flags = EDGE_FALLTHRU;
4789 /* Redirect E to DEST. Return NULL on failure. Otherwise, return the
4790 edge representing the redirected branch. */
4793 tree_redirect_edge_and_branch (edge e, basic_block dest)
4795 basic_block bb = e->src;
4796 block_stmt_iterator bsi;
4800 if (e->flags & EDGE_ABNORMAL)
4803 if (e->src != ENTRY_BLOCK_PTR
4804 && (ret = tree_try_redirect_by_replacing_jump (e, dest)))
4807 if (e->dest == dest)
4810 bsi = bsi_last (bb);
4811 stmt = bsi_end_p (bsi) ? NULL : bsi_stmt (bsi);
4813 switch (stmt ? TREE_CODE (stmt) : ERROR_MARK)
4816 /* For COND_EXPR, we only need to redirect the edge. */
4820 /* No non-abnormal edges should lead from a non-simple goto, and
4821 simple ones should be represented implicitly. */
4826 tree cases = get_cases_for_edge (e, stmt);
4827 tree label = tree_block_label (dest);
4829 /* If we have a list of cases associated with E, then use it
4830 as it's a lot faster than walking the entire case vector. */
4833 edge e2 = find_edge (e->src, dest);
4840 CASE_LABEL (cases) = label;
4841 cases = TREE_CHAIN (cases);
4844 /* If there was already an edge in the CFG, then we need
4845 to move all the cases associated with E to E2. */
4848 tree cases2 = get_cases_for_edge (e2, stmt);
4850 TREE_CHAIN (last) = TREE_CHAIN (cases2);
4851 TREE_CHAIN (cases2) = first;
4856 tree vec = SWITCH_LABELS (stmt);
4857 size_t i, n = TREE_VEC_LENGTH (vec);
4859 for (i = 0; i < n; i++)
4861 tree elt = TREE_VEC_ELT (vec, i);
4863 if (label_to_block (CASE_LABEL (elt)) == e->dest)
4864 CASE_LABEL (elt) = label;
4872 bsi_remove (&bsi, true);
4873 e->flags |= EDGE_FALLTHRU;
4878 case OMP_SECTIONS_SWITCH:
4880 /* The edges from OMP constructs can be simply redirected. */
4884 /* Otherwise it must be a fallthru edge, and we don't need to
4885 do anything besides redirecting it. */
4886 gcc_assert (e->flags & EDGE_FALLTHRU);
4890 /* Update/insert PHI nodes as necessary. */
4892 /* Now update the edges in the CFG. */
4893 e = ssa_redirect_edge (e, dest);
4898 /* Returns true if it is possible to remove edge E by redirecting
4899 it to the destination of the other edge from E->src. */
4902 tree_can_remove_branch_p (const_edge e)
4904 if (e->flags & EDGE_ABNORMAL)
4910 /* Simple wrapper, as we can always redirect fallthru edges. */
4913 tree_redirect_edge_and_branch_force (edge e, basic_block dest)
4915 e = tree_redirect_edge_and_branch (e, dest);
4922 /* Splits basic block BB after statement STMT (but at least after the
4923 labels). If STMT is NULL, BB is split just after the labels. */
4926 tree_split_block (basic_block bb, void *stmt)
4928 block_stmt_iterator bsi;
4929 tree_stmt_iterator tsi_tgt;
4935 new_bb = create_empty_bb (bb);
4937 /* Redirect the outgoing edges. */
4938 new_bb->succs = bb->succs;
4940 FOR_EACH_EDGE (e, ei, new_bb->succs)
4943 if (stmt && TREE_CODE ((tree) stmt) == LABEL_EXPR)
4946 /* Move everything from BSI to the new basic block. */
4947 for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
4949 act = bsi_stmt (bsi);
4950 if (TREE_CODE (act) == LABEL_EXPR)
4963 if (bsi_end_p (bsi))
4966 /* Split the statement list - avoid re-creating new containers as this
4967 brings ugly quadratic memory consumption in the inliner.
4968 (We are still quadratic since we need to update stmt BB pointers,
4970 list = tsi_split_statement_list_before (&bsi.tsi);
4971 set_bb_stmt_list (new_bb, list);
4972 for (tsi_tgt = tsi_start (list);
4973 !tsi_end_p (tsi_tgt); tsi_next (&tsi_tgt))
4974 change_bb_for_stmt (tsi_stmt (tsi_tgt), new_bb);
4980 /* Moves basic block BB after block AFTER. */
4983 tree_move_block_after (basic_block bb, basic_block after)
4985 if (bb->prev_bb == after)
4989 link_block (bb, after);
4995 /* Return true if basic_block can be duplicated. */
4998 tree_can_duplicate_bb_p (const_basic_block bb ATTRIBUTE_UNUSED)
5004 /* Create a duplicate of the basic block BB. NOTE: This does not
5005 preserve SSA form. */
5008 tree_duplicate_bb (basic_block bb)
5011 block_stmt_iterator bsi, bsi_tgt;
5014 new_bb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb);
5016 /* Copy the PHI nodes. We ignore PHI node arguments here because
5017 the incoming edges have not been setup yet. */
5018 for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
5020 tree copy = create_phi_node (PHI_RESULT (phi), new_bb);
5021 create_new_def_for (PHI_RESULT (copy), copy, PHI_RESULT_PTR (copy));
5024 /* Keep the chain of PHI nodes in the same order so that they can be
5025 updated by ssa_redirect_edge. */
5026 set_phi_nodes (new_bb, phi_reverse (phi_nodes (new_bb)));
5028 bsi_tgt = bsi_start (new_bb);
5029 for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
5031 def_operand_p def_p;
5032 ssa_op_iter op_iter;
5036 stmt = bsi_stmt (bsi);
5037 if (TREE_CODE (stmt) == LABEL_EXPR)
5040 /* Create a new copy of STMT and duplicate STMT's virtual
5042 copy = unshare_expr (stmt);
5043 bsi_insert_after (&bsi_tgt, copy, BSI_NEW_STMT);
5044 copy_virtual_operands (copy, stmt);
5045 region = lookup_stmt_eh_region (stmt);
5047 add_stmt_to_eh_region (copy, region);
5048 gimple_duplicate_stmt_histograms (cfun, copy, cfun, stmt);
5050 /* Create new names for all the definitions created by COPY and
5051 add replacement mappings for each new name. */
5052 FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS)
5053 create_new_def_for (DEF_FROM_PTR (def_p), copy, def_p);
5059 /* Adds phi node arguments for edge E_COPY after basic block duplication. */
5062 add_phi_args_after_copy_edge (edge e_copy)
5064 basic_block bb, bb_copy = e_copy->src, dest;
5067 tree phi, phi_copy, phi_next, def;
5069 if (!phi_nodes (e_copy->dest))
5072 bb = bb_copy->flags & BB_DUPLICATED ? get_bb_original (bb_copy) : bb_copy;
5074 if (e_copy->dest->flags & BB_DUPLICATED)
5075 dest = get_bb_original (e_copy->dest);
5077 dest = e_copy->dest;
5079 e = find_edge (bb, dest);
5082 /* During loop unrolling the target of the latch edge is copied.
5083 In this case we are not looking for edge to dest, but to
5084 duplicated block whose original was dest. */
5085 FOR_EACH_EDGE (e, ei, bb->succs)
5087 if ((e->dest->flags & BB_DUPLICATED)
5088 && get_bb_original (e->dest) == dest)
5092 gcc_assert (e != NULL);
5095 for (phi = phi_nodes (e->dest), phi_copy = phi_nodes (e_copy->dest);
5097 phi = phi_next, phi_copy = PHI_CHAIN (phi_copy))
5099 phi_next = PHI_CHAIN (phi);
5100 def = PHI_ARG_DEF_FROM_EDGE (phi, e);
5101 add_phi_arg (phi_copy, def, e_copy);
5106 /* Basic block BB_COPY was created by code duplication. Add phi node
5107 arguments for edges going out of BB_COPY. The blocks that were
5108 duplicated have BB_DUPLICATED set. */
5111 add_phi_args_after_copy_bb (basic_block bb_copy)
5116 FOR_EACH_EDGE (e_copy, ei, bb_copy->succs)
5118 add_phi_args_after_copy_edge (e_copy);
5122 /* Blocks in REGION_COPY array of length N_REGION were created by
5123 duplication of basic blocks. Add phi node arguments for edges
5124 going from these blocks. If E_COPY is not NULL, also add
5125 phi node arguments for its destination.*/
5128 add_phi_args_after_copy (basic_block *region_copy, unsigned n_region,
5133 for (i = 0; i < n_region; i++)
5134 region_copy[i]->flags |= BB_DUPLICATED;
5136 for (i = 0; i < n_region; i++)
5137 add_phi_args_after_copy_bb (region_copy[i]);
5139 add_phi_args_after_copy_edge (e_copy);
5141 for (i = 0; i < n_region; i++)
5142 region_copy[i]->flags &= ~BB_DUPLICATED;
5145 /* Duplicates a REGION (set of N_REGION basic blocks) with just a single
5146 important exit edge EXIT. By important we mean that no SSA name defined
5147 inside region is live over the other exit edges of the region. All entry
5148 edges to the region must go to ENTRY->dest. The edge ENTRY is redirected
5149 to the duplicate of the region. SSA form, dominance and loop information
5150 is updated. The new basic blocks are stored to REGION_COPY in the same
5151 order as they had in REGION, provided that REGION_COPY is not NULL.
5152 The function returns false if it is unable to copy the region,
5156 tree_duplicate_sese_region (edge entry, edge exit,
5157 basic_block *region, unsigned n_region,
5158 basic_block *region_copy)
5161 bool free_region_copy = false, copying_header = false;
5162 struct loop *loop = entry->dest->loop_father;
5164 VEC (basic_block, heap) *doms;
5166 int total_freq = 0, entry_freq = 0;
5167 gcov_type total_count = 0, entry_count = 0;
5169 if (!can_copy_bbs_p (region, n_region))
5172 /* Some sanity checking. Note that we do not check for all possible
5173 missuses of the functions. I.e. if you ask to copy something weird,
5174 it will work, but the state of structures probably will not be
5176 for (i = 0; i < n_region; i++)
5178 /* We do not handle subloops, i.e. all the blocks must belong to the
5180 if (region[i]->loop_father != loop)
5183 if (region[i] != entry->dest
5184 && region[i] == loop->header)
5188 set_loop_copy (loop, loop);
5190 /* In case the function is used for loop header copying (which is the primary
5191 use), ensure that EXIT and its copy will be new latch and entry edges. */
5192 if (loop->header == entry->dest)
5194 copying_header = true;
5195 set_loop_copy (loop, loop_outer (loop));
5197 if (!dominated_by_p (CDI_DOMINATORS, loop->latch, exit->src))
5200 for (i = 0; i < n_region; i++)
5201 if (region[i] != exit->src
5202 && dominated_by_p (CDI_DOMINATORS, region[i], exit->src))
5208 region_copy = XNEWVEC (basic_block, n_region);
5209 free_region_copy = true;
5212 gcc_assert (!need_ssa_update_p ());
5214 /* Record blocks outside the region that are dominated by something
5217 initialize_original_copy_tables ();
5219 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5221 if (entry->dest->count)
5223 total_count = entry->dest->count;
5224 entry_count = entry->count;
5225 /* Fix up corner cases, to avoid division by zero or creation of negative
5227 if (entry_count > total_count)
5228 entry_count = total_count;
5232 total_freq = entry->dest->frequency;
5233 entry_freq = EDGE_FREQUENCY (entry);
5234 /* Fix up corner cases, to avoid division by zero or creation of negative
5236 if (total_freq == 0)
5238 else if (entry_freq > total_freq)
5239 entry_freq = total_freq;
5242 copy_bbs (region, n_region, region_copy, &exit, 1, &exit_copy, loop,
5243 split_edge_bb_loc (entry));
5246 scale_bbs_frequencies_gcov_type (region, n_region,
5247 total_count - entry_count,
5249 scale_bbs_frequencies_gcov_type (region_copy, n_region, entry_count,
5254 scale_bbs_frequencies_int (region, n_region, total_freq - entry_freq,
5256 scale_bbs_frequencies_int (region_copy, n_region, entry_freq, total_freq);
5261 loop->header = exit->dest;
5262 loop->latch = exit->src;
5265 /* Redirect the entry and add the phi node arguments. */
5266 redirected = redirect_edge_and_branch (entry, get_bb_copy (entry->dest));
5267 gcc_assert (redirected != NULL);
5268 flush_pending_stmts (entry);
5270 /* Concerning updating of dominators: We must recount dominators
5271 for entry block and its copy. Anything that is outside of the
5272 region, but was dominated by something inside needs recounting as
5274 set_immediate_dominator (CDI_DOMINATORS, entry->dest, entry->src);
5275 VEC_safe_push (basic_block, heap, doms, get_bb_original (entry->dest));
5276 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5277 VEC_free (basic_block, heap, doms);
5279 /* Add the other PHI node arguments. */
5280 add_phi_args_after_copy (region_copy, n_region, NULL);
5282 /* Update the SSA web. */
5283 update_ssa (TODO_update_ssa);
5285 if (free_region_copy)
5288 free_original_copy_tables ();
5292 /* Duplicates REGION consisting of N_REGION blocks. The new blocks
5293 are stored to REGION_COPY in the same order in that they appear
5294 in REGION, if REGION_COPY is not NULL. ENTRY is the entry to
5295 the region, EXIT an exit from it. The condition guarding EXIT
5296 is moved to ENTRY. Returns true if duplication succeeds, false
5322 tree_duplicate_sese_tail (edge entry, edge exit,
5323 basic_block *region, unsigned n_region,
5324 basic_block *region_copy)
5327 bool free_region_copy = false;
5328 struct loop *loop = exit->dest->loop_father;
5329 struct loop *orig_loop = entry->dest->loop_father;
5330 basic_block switch_bb, entry_bb, nentry_bb;
5331 VEC (basic_block, heap) *doms;
5332 int total_freq = 0, exit_freq = 0;
5333 gcov_type total_count = 0, exit_count = 0;
5334 edge exits[2], nexits[2], e;
5335 block_stmt_iterator bsi;
5339 gcc_assert (EDGE_COUNT (exit->src->succs) == 2);
5341 exits[1] = EDGE_SUCC (exit->src, EDGE_SUCC (exit->src, 0) == exit);
5343 if (!can_copy_bbs_p (region, n_region))
5346 /* Some sanity checking. Note that we do not check for all possible
5347 missuses of the functions. I.e. if you ask to copy something weird
5348 (e.g., in the example, if there is a jump from inside to the middle
5349 of some_code, or come_code defines some of the values used in cond)
5350 it will work, but the resulting code will not be correct. */
5351 for (i = 0; i < n_region; i++)
5353 /* We do not handle subloops, i.e. all the blocks must belong to the
5355 if (region[i]->loop_father != orig_loop)
5358 if (region[i] == orig_loop->latch)
5362 initialize_original_copy_tables ();
5363 set_loop_copy (orig_loop, loop);
5367 region_copy = XNEWVEC (basic_block, n_region);
5368 free_region_copy = true;
5371 gcc_assert (!need_ssa_update_p ());
5373 /* Record blocks outside the region that are dominated by something
5375 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5377 if (exit->src->count)
5379 total_count = exit->src->count;
5380 exit_count = exit->count;
5381 /* Fix up corner cases, to avoid division by zero or creation of negative
5383 if (exit_count > total_count)
5384 exit_count = total_count;
5388 total_freq = exit->src->frequency;
5389 exit_freq = EDGE_FREQUENCY (exit);
5390 /* Fix up corner cases, to avoid division by zero or creation of negative
5392 if (total_freq == 0)
5394 if (exit_freq > total_freq)
5395 exit_freq = total_freq;
5398 copy_bbs (region, n_region, region_copy, exits, 2, nexits, orig_loop,
5399 split_edge_bb_loc (exit));
5402 scale_bbs_frequencies_gcov_type (region, n_region,
5403 total_count - exit_count,
5405 scale_bbs_frequencies_gcov_type (region_copy, n_region, exit_count,
5410 scale_bbs_frequencies_int (region, n_region, total_freq - exit_freq,
5412 scale_bbs_frequencies_int (region_copy, n_region, exit_freq, total_freq);
5415 /* Create the switch block, and put the exit condition to it. */
5416 entry_bb = entry->dest;
5417 nentry_bb = get_bb_copy (entry_bb);
5418 if (!last_stmt (entry->src)
5419 || !stmt_ends_bb_p (last_stmt (entry->src)))
5420 switch_bb = entry->src;
5422 switch_bb = split_edge (entry);
5423 set_immediate_dominator (CDI_DOMINATORS, nentry_bb, switch_bb);
5425 bsi = bsi_last (switch_bb);
5426 cond = last_stmt (exit->src);
5427 gcc_assert (TREE_CODE (cond) == COND_EXPR);
5428 bsi_insert_after (&bsi, unshare_expr (cond), BSI_NEW_STMT);
5430 sorig = single_succ_edge (switch_bb);
5431 sorig->flags = exits[1]->flags;
5432 snew = make_edge (switch_bb, nentry_bb, exits[0]->flags);
5434 /* Register the new edge from SWITCH_BB in loop exit lists. */
5435 rescan_loop_exit (snew, true, false);
5437 /* Add the PHI node arguments. */
5438 add_phi_args_after_copy (region_copy, n_region, snew);
5440 /* Get rid of now superfluous conditions and associated edges (and phi node
5442 e = redirect_edge_and_branch (exits[0], exits[1]->dest);
5443 PENDING_STMT (e) = NULL_TREE;
5444 e = redirect_edge_and_branch (nexits[1], nexits[0]->dest);
5445 PENDING_STMT (e) = NULL_TREE;
5447 /* Anything that is outside of the region, but was dominated by something
5448 inside needs to update dominance info. */
5449 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5450 VEC_free (basic_block, heap, doms);
5452 /* Update the SSA web. */
5453 update_ssa (TODO_update_ssa);
5455 if (free_region_copy)
5458 free_original_copy_tables ();
5463 DEF_VEC_P(basic_block);
5464 DEF_VEC_ALLOC_P(basic_block,heap);
5467 /* Add all the blocks dominated by ENTRY to the array BBS_P. Stop
5468 adding blocks when the dominator traversal reaches EXIT. This
5469 function silently assumes that ENTRY strictly dominates EXIT. */
5472 gather_blocks_in_sese_region (basic_block entry, basic_block exit,
5473 VEC(basic_block,heap) **bbs_p)
5477 for (son = first_dom_son (CDI_DOMINATORS, entry);
5479 son = next_dom_son (CDI_DOMINATORS, son))
5481 VEC_safe_push (basic_block, heap, *bbs_p, son);
5483 gather_blocks_in_sese_region (son, exit, bbs_p);
5487 /* Replaces *TP with a duplicate (belonging to function TO_CONTEXT).
5488 The duplicates are recorded in VARS_MAP. */
5491 replace_by_duplicate_decl (tree *tp, struct pointer_map_t *vars_map,
5494 tree t = *tp, new_t;
5495 struct function *f = DECL_STRUCT_FUNCTION (to_context);
5498 if (DECL_CONTEXT (t) == to_context)
5501 loc = pointer_map_contains (vars_map, t);
5505 loc = pointer_map_insert (vars_map, t);
5509 new_t = copy_var_decl (t, DECL_NAME (t), TREE_TYPE (t));
5510 f->unexpanded_var_list
5511 = tree_cons (NULL_TREE, new_t, f->unexpanded_var_list);
5515 gcc_assert (TREE_CODE (t) == CONST_DECL);
5516 new_t = copy_node (t);
5518 DECL_CONTEXT (new_t) = to_context;
5528 /* Creates an ssa name in TO_CONTEXT equivalent to NAME.
5529 VARS_MAP maps old ssa names and var_decls to the new ones. */
5532 replace_ssa_name (tree name, struct pointer_map_t *vars_map,
5536 tree new_name, decl = SSA_NAME_VAR (name);
5538 gcc_assert (is_gimple_reg (name));
5540 loc = pointer_map_contains (vars_map, name);
5544 replace_by_duplicate_decl (&decl, vars_map, to_context);
5546 push_cfun (DECL_STRUCT_FUNCTION (to_context));
5547 if (gimple_in_ssa_p (cfun))
5548 add_referenced_var (decl);
5550 new_name = make_ssa_name (decl, SSA_NAME_DEF_STMT (name));
5551 if (SSA_NAME_IS_DEFAULT_DEF (name))
5552 set_default_def (decl, new_name);
5555 loc = pointer_map_insert (vars_map, name);
5569 struct pointer_map_t *vars_map;
5570 htab_t new_label_map;
5574 /* Helper for move_block_to_fn. Set TREE_BLOCK in every expression
5575 contained in *TP and change the DECL_CONTEXT of every local
5576 variable referenced in *TP. */
5579 move_stmt_r (tree *tp, int *walk_subtrees, void *data)
5581 struct move_stmt_d *p = (struct move_stmt_d *) data;
5585 && (EXPR_P (t) || GIMPLE_STMT_P (t)))
5586 TREE_BLOCK (t) = p->block;
5588 if (OMP_DIRECTIVE_P (t)
5589 && TREE_CODE (t) != OMP_RETURN
5590 && TREE_CODE (t) != OMP_CONTINUE)
5592 /* Do not remap variables inside OMP directives. Variables
5593 referenced in clauses and directive header belong to the
5594 parent function and should not be moved into the child
5596 bool save_remap_decls_p = p->remap_decls_p;
5597 p->remap_decls_p = false;
5600 walk_tree (&OMP_BODY (t), move_stmt_r, p, NULL);
5602 p->remap_decls_p = save_remap_decls_p;
5604 else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
5606 if (TREE_CODE (t) == SSA_NAME)
5607 *tp = replace_ssa_name (t, p->vars_map, p->to_context);
5608 else if (TREE_CODE (t) == LABEL_DECL)
5610 if (p->new_label_map)
5612 struct tree_map in, *out;
5614 out = htab_find_with_hash (p->new_label_map, &in, DECL_UID (t));
5619 DECL_CONTEXT (t) = p->to_context;
5621 else if (p->remap_decls_p)
5623 /* Replace T with its duplicate. T should no longer appear in the
5624 parent function, so this looks wasteful; however, it may appear
5625 in referenced_vars, and more importantly, as virtual operands of
5626 statements, and in alias lists of other variables. It would be
5627 quite difficult to expunge it from all those places. ??? It might
5628 suffice to do this for addressable variables. */
5629 if ((TREE_CODE (t) == VAR_DECL
5630 && !is_global_var (t))
5631 || TREE_CODE (t) == CONST_DECL)
5632 replace_by_duplicate_decl (tp, p->vars_map, p->to_context);
5635 && gimple_in_ssa_p (cfun))
5637 push_cfun (DECL_STRUCT_FUNCTION (p->to_context));
5638 add_referenced_var (*tp);
5644 else if (TYPE_P (t))
5650 /* Marks virtual operands of all statements in basic blocks BBS for
5654 mark_virtual_ops_in_bb (basic_block bb)
5657 block_stmt_iterator bsi;
5659 for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
5660 mark_virtual_ops_for_renaming (phi);
5662 for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
5663 mark_virtual_ops_for_renaming (bsi_stmt (bsi));
5666 /* Marks virtual operands of all statements in basic blocks BBS for
5670 mark_virtual_ops_in_region (VEC (basic_block,heap) *bbs)
5675 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
5676 mark_virtual_ops_in_bb (bb);
5679 /* Move basic block BB from function CFUN to function DEST_FN. The
5680 block is moved out of the original linked list and placed after
5681 block AFTER in the new list. Also, the block is removed from the
5682 original array of blocks and placed in DEST_FN's array of blocks.
5683 If UPDATE_EDGE_COUNT_P is true, the edge counts on both CFGs is
5684 updated to reflect the moved edges.
5686 The local variables are remapped to new instances, VARS_MAP is used
5687 to record the mapping. */
5690 move_block_to_fn (struct function *dest_cfun, basic_block bb,
5691 basic_block after, bool update_edge_count_p,
5692 struct pointer_map_t *vars_map, htab_t new_label_map,
5695 struct control_flow_graph *cfg;
5698 block_stmt_iterator si;
5699 struct move_stmt_d d;
5700 unsigned old_len, new_len;
5703 /* Remove BB from dominance structures. */
5704 delete_from_dominance_info (CDI_DOMINATORS, bb);
5706 remove_bb_from_loops (bb);
5708 /* Link BB to the new linked list. */
5709 move_block_after (bb, after);
5711 /* Update the edge count in the corresponding flowgraphs. */
5712 if (update_edge_count_p)
5713 FOR_EACH_EDGE (e, ei, bb->succs)
5715 cfun->cfg->x_n_edges--;
5716 dest_cfun->cfg->x_n_edges++;
5719 /* Remove BB from the original basic block array. */
5720 VEC_replace (basic_block, cfun->cfg->x_basic_block_info, bb->index, NULL);
5721 cfun->cfg->x_n_basic_blocks--;
5723 /* Grow DEST_CFUN's basic block array if needed. */
5724 cfg = dest_cfun->cfg;
5725 cfg->x_n_basic_blocks++;
5726 if (bb->index >= cfg->x_last_basic_block)
5727 cfg->x_last_basic_block = bb->index + 1;
5729 old_len = VEC_length (basic_block, cfg->x_basic_block_info);
5730 if ((unsigned) cfg->x_last_basic_block >= old_len)
5732 new_len = cfg->x_last_basic_block + (cfg->x_last_basic_block + 3) / 4;
5733 VEC_safe_grow_cleared (basic_block, gc, cfg->x_basic_block_info,
5737 VEC_replace (basic_block, cfg->x_basic_block_info,
5740 /* Remap the variables in phi nodes. */
5741 for (phi = phi_nodes (bb); phi; phi = next_phi)
5744 tree op = PHI_RESULT (phi);
5747 next_phi = PHI_CHAIN (phi);
5748 if (!is_gimple_reg (op))
5750 /* Remove the phi nodes for virtual operands (alias analysis will be
5751 run for the new function, anyway). */
5752 remove_phi_node (phi, NULL, true);
5756 SET_PHI_RESULT (phi, replace_ssa_name (op, vars_map, dest_cfun->decl));
5757 FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
5759 op = USE_FROM_PTR (use);
5760 if (TREE_CODE (op) == SSA_NAME)
5761 SET_USE (use, replace_ssa_name (op, vars_map, dest_cfun->decl));
5765 /* The statements in BB need to be associated with a new TREE_BLOCK.
5766 Labels need to be associated with a new label-to-block map. */
5767 memset (&d, 0, sizeof (d));
5768 d.vars_map = vars_map;
5769 d.from_context = cfun->decl;
5770 d.to_context = dest_cfun->decl;
5771 d.new_label_map = new_label_map;
5773 for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
5775 tree stmt = bsi_stmt (si);
5778 d.remap_decls_p = true;
5779 if (TREE_BLOCK (stmt))
5780 d.block = DECL_INITIAL (dest_cfun->decl);
5782 walk_tree (&stmt, move_stmt_r, &d, NULL);
5784 if (TREE_CODE (stmt) == LABEL_EXPR)
5786 tree label = LABEL_EXPR_LABEL (stmt);
5787 int uid = LABEL_DECL_UID (label);
5789 gcc_assert (uid > -1);
5791 old_len = VEC_length (basic_block, cfg->x_label_to_block_map);
5792 if (old_len <= (unsigned) uid)
5794 new_len = 3 * uid / 2;
5795 VEC_safe_grow_cleared (basic_block, gc,
5796 cfg->x_label_to_block_map, new_len);
5799 VEC_replace (basic_block, cfg->x_label_to_block_map, uid, bb);
5800 VEC_replace (basic_block, cfun->cfg->x_label_to_block_map, uid, NULL);
5802 gcc_assert (DECL_CONTEXT (label) == dest_cfun->decl);
5804 if (uid >= dest_cfun->last_label_uid)
5805 dest_cfun->last_label_uid = uid + 1;
5807 else if (TREE_CODE (stmt) == RESX_EXPR && eh_offset != 0)
5808 TREE_OPERAND (stmt, 0) =
5809 build_int_cst (NULL_TREE,
5810 TREE_INT_CST_LOW (TREE_OPERAND (stmt, 0))
5813 region = lookup_stmt_eh_region (stmt);
5816 add_stmt_to_eh_region_fn (dest_cfun, stmt, region + eh_offset);
5817 remove_stmt_from_eh_region (stmt);
5818 gimple_duplicate_stmt_histograms (dest_cfun, stmt, cfun, stmt);
5819 gimple_remove_stmt_histograms (cfun, stmt);
5822 /* We cannot leave any operands allocated from the operand caches of
5823 the current function. */
5824 free_stmt_operands (stmt);
5825 push_cfun (dest_cfun);
5831 /* Examine the statements in BB (which is in SRC_CFUN); find and return
5832 the outermost EH region. Use REGION as the incoming base EH region. */
5835 find_outermost_region_in_block (struct function *src_cfun,
5836 basic_block bb, int region)
5838 block_stmt_iterator si;
5840 for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si))
5842 tree stmt = bsi_stmt (si);
5845 if (TREE_CODE (stmt) == RESX_EXPR)
5846 stmt_region = TREE_INT_CST_LOW (TREE_OPERAND (stmt, 0));
5848 stmt_region = lookup_stmt_eh_region_fn (src_cfun, stmt);
5849 if (stmt_region > 0)
5852 region = stmt_region;
5853 else if (stmt_region != region)
5855 region = eh_region_outermost (src_cfun, stmt_region, region);
5856 gcc_assert (region != -1);
5865 new_label_mapper (tree decl, void *data)
5867 htab_t hash = (htab_t) data;
5871 gcc_assert (TREE_CODE (decl) == LABEL_DECL);
5873 m = xmalloc (sizeof (struct tree_map));
5874 m->hash = DECL_UID (decl);
5875 m->base.from = decl;
5876 m->to = create_artificial_label ();
5877 LABEL_DECL_UID (m->to) = LABEL_DECL_UID (decl);
5879 slot = htab_find_slot_with_hash (hash, m, m->hash, INSERT);
5880 gcc_assert (*slot == NULL);
5887 /* Move a single-entry, single-exit region delimited by ENTRY_BB and
5888 EXIT_BB to function DEST_CFUN. The whole region is replaced by a
5889 single basic block in the original CFG and the new basic block is
5890 returned. DEST_CFUN must not have a CFG yet.
5892 Note that the region need not be a pure SESE region. Blocks inside
5893 the region may contain calls to abort/exit. The only restriction
5894 is that ENTRY_BB should be the only entry point and it must
5897 All local variables referenced in the region are assumed to be in
5898 the corresponding BLOCK_VARS and unexpanded variable lists
5899 associated with DEST_CFUN. */
5902 move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb,
5903 basic_block exit_bb)
5905 VEC(basic_block,heap) *bbs, *dom_bbs;
5906 basic_block dom_entry = get_immediate_dominator (CDI_DOMINATORS, entry_bb);
5907 basic_block after, bb, *entry_pred, *exit_succ, abb;
5908 struct function *saved_cfun = cfun;
5909 int *entry_flag, *exit_flag, eh_offset;
5910 unsigned *entry_prob, *exit_prob;
5911 unsigned i, num_entry_edges, num_exit_edges;
5914 htab_t new_label_map;
5915 struct pointer_map_t *vars_map;
5916 struct loop *loop = entry_bb->loop_father;
5918 /* If ENTRY does not strictly dominate EXIT, this cannot be an SESE
5920 gcc_assert (entry_bb != exit_bb
5922 || dominated_by_p (CDI_DOMINATORS, exit_bb, entry_bb)));
5924 /* Collect all the blocks in the region. Manually add ENTRY_BB
5925 because it won't be added by dfs_enumerate_from. */
5927 VEC_safe_push (basic_block, heap, bbs, entry_bb);
5928 gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs);
5930 /* The blocks that used to be dominated by something in BBS will now be
5931 dominated by the new block. */
5932 dom_bbs = get_dominated_by_region (CDI_DOMINATORS,
5933 VEC_address (basic_block, bbs),
5934 VEC_length (basic_block, bbs));
5936 /* Detach ENTRY_BB and EXIT_BB from CFUN->CFG. We need to remember
5937 the predecessor edges to ENTRY_BB and the successor edges to
5938 EXIT_BB so that we can re-attach them to the new basic block that
5939 will replace the region. */
5940 num_entry_edges = EDGE_COUNT (entry_bb->preds);
5941 entry_pred = (basic_block *) xcalloc (num_entry_edges, sizeof (basic_block));
5942 entry_flag = (int *) xcalloc (num_entry_edges, sizeof (int));
5943 entry_prob = XNEWVEC (unsigned, num_entry_edges);
5945 for (ei = ei_start (entry_bb->preds); (e = ei_safe_edge (ei)) != NULL;)
5947 entry_prob[i] = e->probability;
5948 entry_flag[i] = e->flags;
5949 entry_pred[i++] = e->src;
5955 num_exit_edges = EDGE_COUNT (exit_bb->succs);
5956 exit_succ = (basic_block *) xcalloc (num_exit_edges,
5957 sizeof (basic_block));
5958 exit_flag = (int *) xcalloc (num_exit_edges, sizeof (int));
5959 exit_prob = XNEWVEC (unsigned, num_exit_edges);
5961 for (ei = ei_start (exit_bb->succs); (e = ei_safe_edge (ei)) != NULL;)
5963 exit_prob[i] = e->probability;
5964 exit_flag[i] = e->flags;
5965 exit_succ[i++] = e->dest;
5977 /* Switch context to the child function to initialize DEST_FN's CFG. */
5978 gcc_assert (dest_cfun->cfg == NULL);
5979 push_cfun (dest_cfun);
5981 init_empty_tree_cfg ();
5983 /* Initialize EH information for the new function. */
5985 new_label_map = NULL;
5990 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
5991 region = find_outermost_region_in_block (saved_cfun, bb, region);
5993 init_eh_for_function ();
5996 new_label_map = htab_create (17, tree_map_hash, tree_map_eq, free);
5997 eh_offset = duplicate_eh_regions (saved_cfun, new_label_mapper,
5998 new_label_map, region, 0);
6004 /* The ssa form for virtual operands in the source function will have to
6005 be repaired. We do not care for the real operands -- the sese region
6006 must be closed with respect to those. */
6007 mark_virtual_ops_in_region (bbs);
6009 /* Move blocks from BBS into DEST_CFUN. */
6010 gcc_assert (VEC_length (basic_block, bbs) >= 2);
6011 after = dest_cfun->cfg->x_entry_block_ptr;
6012 vars_map = pointer_map_create ();
6013 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6015 /* No need to update edge counts on the last block. It has
6016 already been updated earlier when we detached the region from
6017 the original CFG. */
6018 move_block_to_fn (dest_cfun, bb, after, bb != exit_bb, vars_map,
6019 new_label_map, eh_offset);
6024 htab_delete (new_label_map);
6025 pointer_map_destroy (vars_map);
6027 /* Rewire the entry and exit blocks. The successor to the entry
6028 block turns into the successor of DEST_FN's ENTRY_BLOCK_PTR in
6029 the child function. Similarly, the predecessor of DEST_FN's
6030 EXIT_BLOCK_PTR turns into the predecessor of EXIT_BLOCK_PTR. We
6031 need to switch CFUN between DEST_CFUN and SAVED_CFUN so that the
6032 various CFG manipulation function get to the right CFG.
6034 FIXME, this is silly. The CFG ought to become a parameter to
6036 push_cfun (dest_cfun);
6037 make_edge (ENTRY_BLOCK_PTR, entry_bb, EDGE_FALLTHRU);
6039 make_edge (exit_bb, EXIT_BLOCK_PTR, 0);
6042 /* Back in the original function, the SESE region has disappeared,
6043 create a new basic block in its place. */
6044 bb = create_empty_bb (entry_pred[0]);
6046 add_bb_to_loop (bb, loop);
6047 for (i = 0; i < num_entry_edges; i++)
6049 e = make_edge (entry_pred[i], bb, entry_flag[i]);
6050 e->probability = entry_prob[i];
6053 for (i = 0; i < num_exit_edges; i++)
6055 e = make_edge (bb, exit_succ[i], exit_flag[i]);
6056 e->probability = exit_prob[i];
6059 set_immediate_dominator (CDI_DOMINATORS, bb, dom_entry);
6060 for (i = 0; VEC_iterate (basic_block, dom_bbs, i, abb); i++)
6061 set_immediate_dominator (CDI_DOMINATORS, abb, bb);
6062 VEC_free (basic_block, heap, dom_bbs);
6073 VEC_free (basic_block, heap, bbs);
6079 /* Dump FUNCTION_DECL FN to file FILE using FLAGS (see TDF_* in tree.h) */
6082 dump_function_to_file (tree fn, FILE *file, int flags)
6084 tree arg, vars, var;
6085 struct function *dsf;
6086 bool ignore_topmost_bind = false, any_var = false;
6090 fprintf (file, "%s (", lang_hooks.decl_printable_name (fn, 2));
6092 arg = DECL_ARGUMENTS (fn);
6095 print_generic_expr (file, arg, dump_flags);
6096 if (TREE_CHAIN (arg))
6097 fprintf (file, ", ");
6098 arg = TREE_CHAIN (arg);
6100 fprintf (file, ")\n");
6102 dsf = DECL_STRUCT_FUNCTION (fn);
6103 if (dsf && (flags & TDF_DETAILS))
6104 dump_eh_tree (file, dsf);
6106 if (flags & TDF_RAW)
6108 dump_node (fn, TDF_SLIM | flags, file);
6112 /* Switch CFUN to point to FN. */
6113 push_cfun (DECL_STRUCT_FUNCTION (fn));
6115 /* When GIMPLE is lowered, the variables are no longer available in
6116 BIND_EXPRs, so display them separately. */
6117 if (cfun && cfun->decl == fn && cfun->unexpanded_var_list)
6119 ignore_topmost_bind = true;
6121 fprintf (file, "{\n");
6122 for (vars = cfun->unexpanded_var_list; vars; vars = TREE_CHAIN (vars))
6124 var = TREE_VALUE (vars);
6126 print_generic_decl (file, var, flags);
6127 fprintf (file, "\n");
6133 if (cfun && cfun->decl == fn && cfun->cfg && basic_block_info)
6135 /* Make a CFG based dump. */
6136 check_bb_profile (ENTRY_BLOCK_PTR, file);
6137 if (!ignore_topmost_bind)
6138 fprintf (file, "{\n");
6140 if (any_var && n_basic_blocks)
6141 fprintf (file, "\n");
6144 dump_generic_bb (file, bb, 2, flags);
6146 fprintf (file, "}\n");
6147 check_bb_profile (EXIT_BLOCK_PTR, file);
6153 /* Make a tree based dump. */
6154 chain = DECL_SAVED_TREE (fn);
6156 if (chain && TREE_CODE (chain) == BIND_EXPR)
6158 if (ignore_topmost_bind)
6160 chain = BIND_EXPR_BODY (chain);
6168 if (!ignore_topmost_bind)
6169 fprintf (file, "{\n");
6174 fprintf (file, "\n");
6176 print_generic_stmt_indented (file, chain, flags, indent);
6177 if (ignore_topmost_bind)
6178 fprintf (file, "}\n");
6181 fprintf (file, "\n\n");
6188 /* Dump FUNCTION_DECL FN to stderr using FLAGS (see TDF_* in tree.h) */
6191 debug_function (tree fn, int flags)
6193 dump_function_to_file (fn, stderr, flags);
6197 /* Print on FILE the indexes for the predecessors of basic_block BB. */
6200 print_pred_bbs (FILE *file, basic_block bb)
6205 FOR_EACH_EDGE (e, ei, bb->preds)
6206 fprintf (file, "bb_%d ", e->src->index);
6210 /* Print on FILE the indexes for the successors of basic_block BB. */
6213 print_succ_bbs (FILE *file, basic_block bb)
6218 FOR_EACH_EDGE (e, ei, bb->succs)
6219 fprintf (file, "bb_%d ", e->dest->index);
6222 /* Print to FILE the basic block BB following the VERBOSITY level. */
6225 print_loops_bb (FILE *file, basic_block bb, int indent, int verbosity)
6227 char *s_indent = (char *) alloca ((size_t) indent + 1);
6228 memset ((void *) s_indent, ' ', (size_t) indent);
6229 s_indent[indent] = '\0';
6231 /* Print basic_block's header. */
6234 fprintf (file, "%s bb_%d (preds = {", s_indent, bb->index);
6235 print_pred_bbs (file, bb);
6236 fprintf (file, "}, succs = {");
6237 print_succ_bbs (file, bb);
6238 fprintf (file, "})\n");
6241 /* Print basic_block's body. */
6244 fprintf (file, "%s {\n", s_indent);
6245 tree_dump_bb (bb, file, indent + 4);
6246 fprintf (file, "%s }\n", s_indent);
6250 static void print_loop_and_siblings (FILE *, struct loop *, int, int);
6252 /* Pretty print LOOP on FILE, indented INDENT spaces. Following
6253 VERBOSITY level this outputs the contents of the loop, or just its
6257 print_loop (FILE *file, struct loop *loop, int indent, int verbosity)
6265 s_indent = (char *) alloca ((size_t) indent + 1);
6266 memset ((void *) s_indent, ' ', (size_t) indent);
6267 s_indent[indent] = '\0';
6269 /* Print loop's header. */
6270 fprintf (file, "%sloop_%d (header = %d, latch = %d", s_indent,
6271 loop->num, loop->header->index, loop->latch->index);
6272 fprintf (file, ", niter = ");
6273 print_generic_expr (file, loop->nb_iterations, 0);
6275 if (loop->any_upper_bound)
6277 fprintf (file, ", upper_bound = ");
6278 dump_double_int (file, loop->nb_iterations_upper_bound, true);
6281 if (loop->any_estimate)
6283 fprintf (file, ", estimate = ");
6284 dump_double_int (file, loop->nb_iterations_estimate, true);
6286 fprintf (file, ")\n");
6288 /* Print loop's body. */
6291 fprintf (file, "%s{\n", s_indent);
6293 if (bb->loop_father == loop)
6294 print_loops_bb (file, bb, indent, verbosity);
6296 print_loop_and_siblings (file, loop->inner, indent + 2, verbosity);
6297 fprintf (file, "%s}\n", s_indent);
6301 /* Print the LOOP and its sibling loops on FILE, indented INDENT
6302 spaces. Following VERBOSITY level this outputs the contents of the
6303 loop, or just its structure. */
6306 print_loop_and_siblings (FILE *file, struct loop *loop, int indent, int verbosity)
6311 print_loop (file, loop, indent, verbosity);
6312 print_loop_and_siblings (file, loop->next, indent, verbosity);
6315 /* Follow a CFG edge from the entry point of the program, and on entry
6316 of a loop, pretty print the loop structure on FILE. */
6319 print_loops (FILE *file, int verbosity)
6323 bb = BASIC_BLOCK (NUM_FIXED_BLOCKS);
6324 if (bb && bb->loop_father)
6325 print_loop_and_siblings (file, bb->loop_father, 0, verbosity);
6329 /* Debugging loops structure at tree level, at some VERBOSITY level. */
6332 debug_loops (int verbosity)
6334 print_loops (stderr, verbosity);
6337 /* Print on stderr the code of LOOP, at some VERBOSITY level. */
6340 debug_loop (struct loop *loop, int verbosity)
6342 print_loop (stderr, loop, 0, verbosity);
6345 /* Print on stderr the code of loop number NUM, at some VERBOSITY
6349 debug_loop_num (unsigned num, int verbosity)
6351 debug_loop (get_loop (num), verbosity);
6354 /* Return true if BB ends with a call, possibly followed by some
6355 instructions that must stay with the call. Return false,
6359 tree_block_ends_with_call_p (basic_block bb)
6361 block_stmt_iterator bsi = bsi_last (bb);
6362 return get_call_expr_in (bsi_stmt (bsi)) != NULL;
6366 /* Return true if BB ends with a conditional branch. Return false,
6370 tree_block_ends_with_condjump_p (const_basic_block bb)
6372 /* This CONST_CAST is okay because last_stmt doesn't modify its
6373 argument and the return value is not modified. */
6374 const_tree stmt = last_stmt (CONST_CAST_BB(bb));
6375 return (stmt && TREE_CODE (stmt) == COND_EXPR);
6379 /* Return true if we need to add fake edge to exit at statement T.
6380 Helper function for tree_flow_call_edges_add. */
6383 need_fake_edge_p (tree t)
6387 /* NORETURN and LONGJMP calls already have an edge to exit.
6388 CONST and PURE calls do not need one.
6389 We don't currently check for CONST and PURE here, although
6390 it would be a good idea, because those attributes are
6391 figured out from the RTL in mark_constant_function, and
6392 the counter incrementation code from -fprofile-arcs
6393 leads to different results from -fbranch-probabilities. */
6394 call = get_call_expr_in (t);
6396 && !(call_expr_flags (call) & ECF_NORETURN))
6399 if (TREE_CODE (t) == ASM_EXPR
6400 && (ASM_VOLATILE_P (t) || ASM_INPUT_P (t)))
6407 /* Add fake edges to the function exit for any non constant and non
6408 noreturn calls, volatile inline assembly in the bitmap of blocks
6409 specified by BLOCKS or to the whole CFG if BLOCKS is zero. Return
6410 the number of blocks that were split.
6412 The goal is to expose cases in which entering a basic block does
6413 not imply that all subsequent instructions must be executed. */
6416 tree_flow_call_edges_add (sbitmap blocks)
6419 int blocks_split = 0;
6420 int last_bb = last_basic_block;
6421 bool check_last_block = false;
6423 if (n_basic_blocks == NUM_FIXED_BLOCKS)
6427 check_last_block = true;
6429 check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index);
6431 /* In the last basic block, before epilogue generation, there will be
6432 a fallthru edge to EXIT. Special care is required if the last insn
6433 of the last basic block is a call because make_edge folds duplicate
6434 edges, which would result in the fallthru edge also being marked
6435 fake, which would result in the fallthru edge being removed by
6436 remove_fake_edges, which would result in an invalid CFG.
6438 Moreover, we can't elide the outgoing fake edge, since the block
6439 profiler needs to take this into account in order to solve the minimal
6440 spanning tree in the case that the call doesn't return.
6442 Handle this by adding a dummy instruction in a new last basic block. */
6443 if (check_last_block)
6445 basic_block bb = EXIT_BLOCK_PTR->prev_bb;
6446 block_stmt_iterator bsi = bsi_last (bb);
6448 if (!bsi_end_p (bsi))
6451 if (t && need_fake_edge_p (t))
6455 e = find_edge (bb, EXIT_BLOCK_PTR);
6458 bsi_insert_on_edge (e, build_empty_stmt ());
6459 bsi_commit_edge_inserts ();
6464 /* Now add fake edges to the function exit for any non constant
6465 calls since there is no way that we can determine if they will
6467 for (i = 0; i < last_bb; i++)
6469 basic_block bb = BASIC_BLOCK (i);
6470 block_stmt_iterator bsi;
6471 tree stmt, last_stmt;
6476 if (blocks && !TEST_BIT (blocks, i))
6479 bsi = bsi_last (bb);
6480 if (!bsi_end_p (bsi))
6482 last_stmt = bsi_stmt (bsi);
6485 stmt = bsi_stmt (bsi);
6486 if (need_fake_edge_p (stmt))
6489 /* The handling above of the final block before the
6490 epilogue should be enough to verify that there is
6491 no edge to the exit block in CFG already.
6492 Calling make_edge in such case would cause us to
6493 mark that edge as fake and remove it later. */
6494 #ifdef ENABLE_CHECKING
6495 if (stmt == last_stmt)
6497 e = find_edge (bb, EXIT_BLOCK_PTR);
6498 gcc_assert (e == NULL);
6502 /* Note that the following may create a new basic block
6503 and renumber the existing basic blocks. */
6504 if (stmt != last_stmt)
6506 e = split_block (bb, stmt);
6510 make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE);
6514 while (!bsi_end_p (bsi));
6519 verify_flow_info ();
6521 return blocks_split;
6524 /* Purge dead abnormal call edges from basic block BB. */
6527 tree_purge_dead_abnormal_call_edges (basic_block bb)
6529 bool changed = tree_purge_dead_eh_edges (bb);
6531 if (current_function_has_nonlocal_label)
6533 tree stmt = last_stmt (bb);
6537 if (!(stmt && tree_can_make_abnormal_goto (stmt)))
6538 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6540 if (e->flags & EDGE_ABNORMAL)
6549 /* See tree_purge_dead_eh_edges below. */
6551 free_dominance_info (CDI_DOMINATORS);
6557 /* Stores all basic blocks dominated by BB to DOM_BBS. */
6560 get_all_dominated_blocks (basic_block bb, VEC (basic_block, heap) **dom_bbs)
6564 VEC_safe_push (basic_block, heap, *dom_bbs, bb);
6565 for (son = first_dom_son (CDI_DOMINATORS, bb);
6567 son = next_dom_son (CDI_DOMINATORS, son))
6568 get_all_dominated_blocks (son, dom_bbs);
6571 /* Removes edge E and all the blocks dominated by it, and updates dominance
6572 information. The IL in E->src needs to be updated separately.
6573 If dominance info is not available, only the edge E is removed.*/
6576 remove_edge_and_dominated_blocks (edge e)
6578 VEC (basic_block, heap) *bbs_to_remove = NULL;
6579 VEC (basic_block, heap) *bbs_to_fix_dom = NULL;
6583 bool none_removed = false;
6585 basic_block bb, dbb;
6588 if (!dom_info_available_p (CDI_DOMINATORS))
6594 /* No updating is needed for edges to exit. */
6595 if (e->dest == EXIT_BLOCK_PTR)
6597 if (cfgcleanup_altered_bbs)
6598 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6603 /* First, we find the basic blocks to remove. If E->dest has a predecessor
6604 that is not dominated by E->dest, then this set is empty. Otherwise,
6605 all the basic blocks dominated by E->dest are removed.
6607 Also, to DF_IDOM we store the immediate dominators of the blocks in
6608 the dominance frontier of E (i.e., of the successors of the
6609 removed blocks, if there are any, and of E->dest otherwise). */
6610 FOR_EACH_EDGE (f, ei, e->dest->preds)
6615 if (!dominated_by_p (CDI_DOMINATORS, f->src, e->dest))
6617 none_removed = true;
6622 df = BITMAP_ALLOC (NULL);
6623 df_idom = BITMAP_ALLOC (NULL);
6626 bitmap_set_bit (df_idom,
6627 get_immediate_dominator (CDI_DOMINATORS, e->dest)->index);
6630 get_all_dominated_blocks (e->dest, &bbs_to_remove);
6631 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6633 FOR_EACH_EDGE (f, ei, bb->succs)
6635 if (f->dest != EXIT_BLOCK_PTR)
6636 bitmap_set_bit (df, f->dest->index);
6639 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6640 bitmap_clear_bit (df, bb->index);
6642 EXECUTE_IF_SET_IN_BITMAP (df, 0, i, bi)
6644 bb = BASIC_BLOCK (i);
6645 bitmap_set_bit (df_idom,
6646 get_immediate_dominator (CDI_DOMINATORS, bb)->index);
6650 if (cfgcleanup_altered_bbs)
6652 /* Record the set of the altered basic blocks. */
6653 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6654 bitmap_ior_into (cfgcleanup_altered_bbs, df);
6657 /* Remove E and the cancelled blocks. */
6662 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6663 delete_basic_block (bb);
6666 /* Update the dominance information. The immediate dominator may change only
6667 for blocks whose immediate dominator belongs to DF_IDOM:
6669 Suppose that idom(X) = Y before removal of E and idom(X) != Y after the
6670 removal. Let Z the arbitrary block such that idom(Z) = Y and
6671 Z dominates X after the removal. Before removal, there exists a path P
6672 from Y to X that avoids Z. Let F be the last edge on P that is
6673 removed, and let W = F->dest. Before removal, idom(W) = Y (since Y
6674 dominates W, and because of P, Z does not dominate W), and W belongs to
6675 the dominance frontier of E. Therefore, Y belongs to DF_IDOM. */
6676 EXECUTE_IF_SET_IN_BITMAP (df_idom, 0, i, bi)
6678 bb = BASIC_BLOCK (i);
6679 for (dbb = first_dom_son (CDI_DOMINATORS, bb);
6681 dbb = next_dom_son (CDI_DOMINATORS, dbb))
6682 VEC_safe_push (basic_block, heap, bbs_to_fix_dom, dbb);
6685 iterate_fix_dominators (CDI_DOMINATORS, bbs_to_fix_dom, true);
6688 BITMAP_FREE (df_idom);
6689 VEC_free (basic_block, heap, bbs_to_remove);
6690 VEC_free (basic_block, heap, bbs_to_fix_dom);
6693 /* Purge dead EH edges from basic block BB. */
6696 tree_purge_dead_eh_edges (basic_block bb)
6698 bool changed = false;
6701 tree stmt = last_stmt (bb);
6703 if (stmt && tree_can_throw_internal (stmt))
6706 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6708 if (e->flags & EDGE_EH)
6710 remove_edge_and_dominated_blocks (e);
6721 tree_purge_all_dead_eh_edges (const_bitmap blocks)
6723 bool changed = false;
6727 EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
6729 changed |= tree_purge_dead_eh_edges (BASIC_BLOCK (i));
6735 /* This function is called whenever a new edge is created or
6739 tree_execute_on_growing_pred (edge e)
6741 basic_block bb = e->dest;
6744 reserve_phi_args_for_new_edge (bb);
6747 /* This function is called immediately before edge E is removed from
6748 the edge vector E->dest->preds. */
6751 tree_execute_on_shrinking_pred (edge e)
6753 if (phi_nodes (e->dest))
6754 remove_phi_args (e);
6757 /*---------------------------------------------------------------------------
6758 Helper functions for Loop versioning
6759 ---------------------------------------------------------------------------*/
6761 /* Adjust phi nodes for 'first' basic block. 'second' basic block is a copy
6762 of 'first'. Both of them are dominated by 'new_head' basic block. When
6763 'new_head' was created by 'second's incoming edge it received phi arguments
6764 on the edge by split_edge(). Later, additional edge 'e' was created to
6765 connect 'new_head' and 'first'. Now this routine adds phi args on this
6766 additional edge 'e' that new_head to second edge received as part of edge
6771 tree_lv_adjust_loop_header_phi (basic_block first, basic_block second,
6772 basic_block new_head, edge e)
6775 edge e2 = find_edge (new_head, second);
6777 /* Because NEW_HEAD has been created by splitting SECOND's incoming
6778 edge, we should always have an edge from NEW_HEAD to SECOND. */
6779 gcc_assert (e2 != NULL);
6781 /* Browse all 'second' basic block phi nodes and add phi args to
6782 edge 'e' for 'first' head. PHI args are always in correct order. */
6784 for (phi2 = phi_nodes (second), phi1 = phi_nodes (first);
6786 phi2 = PHI_CHAIN (phi2), phi1 = PHI_CHAIN (phi1))
6788 tree def = PHI_ARG_DEF (phi2, e2->dest_idx);
6789 add_phi_arg (phi1, def, e);
6793 /* Adds a if else statement to COND_BB with condition COND_EXPR.
6794 SECOND_HEAD is the destination of the THEN and FIRST_HEAD is
6795 the destination of the ELSE part. */
6797 tree_lv_add_condition_to_bb (basic_block first_head ATTRIBUTE_UNUSED,
6798 basic_block second_head ATTRIBUTE_UNUSED,
6799 basic_block cond_bb, void *cond_e)
6801 block_stmt_iterator bsi;
6802 tree new_cond_expr = NULL_TREE;
6803 tree cond_expr = (tree) cond_e;
6806 /* Build new conditional expr */
6807 new_cond_expr = build3 (COND_EXPR, void_type_node, cond_expr,
6808 NULL_TREE, NULL_TREE);
6810 /* Add new cond in cond_bb. */
6811 bsi = bsi_start (cond_bb);
6812 bsi_insert_after (&bsi, new_cond_expr, BSI_NEW_STMT);
6813 /* Adjust edges appropriately to connect new head with first head
6814 as well as second head. */
6815 e0 = single_succ_edge (cond_bb);
6816 e0->flags &= ~EDGE_FALLTHRU;
6817 e0->flags |= EDGE_FALSE_VALUE;
6820 struct cfg_hooks tree_cfg_hooks = {
6822 tree_verify_flow_info,
6823 tree_dump_bb, /* dump_bb */
6824 create_bb, /* create_basic_block */
6825 tree_redirect_edge_and_branch,/* redirect_edge_and_branch */
6826 tree_redirect_edge_and_branch_force,/* redirect_edge_and_branch_force */
6827 tree_can_remove_branch_p, /* can_remove_branch_p */
6828 remove_bb, /* delete_basic_block */
6829 tree_split_block, /* split_block */
6830 tree_move_block_after, /* move_block_after */
6831 tree_can_merge_blocks_p, /* can_merge_blocks_p */
6832 tree_merge_blocks, /* merge_blocks */
6833 tree_predict_edge, /* predict_edge */
6834 tree_predicted_by_p, /* predicted_by_p */
6835 tree_can_duplicate_bb_p, /* can_duplicate_block_p */
6836 tree_duplicate_bb, /* duplicate_block */
6837 tree_split_edge, /* split_edge */
6838 tree_make_forwarder_block, /* make_forward_block */
6839 NULL, /* tidy_fallthru_edge */
6840 tree_block_ends_with_call_p, /* block_ends_with_call_p */
6841 tree_block_ends_with_condjump_p, /* block_ends_with_condjump_p */
6842 tree_flow_call_edges_add, /* flow_call_edges_add */
6843 tree_execute_on_growing_pred, /* execute_on_growing_pred */
6844 tree_execute_on_shrinking_pred, /* execute_on_shrinking_pred */
6845 tree_duplicate_loop_to_header_edge, /* duplicate loop for trees */
6846 tree_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
6847 tree_lv_adjust_loop_header_phi, /* lv_adjust_loop_header_phi*/
6848 extract_true_false_edges_from_block, /* extract_cond_bb_edges */
6849 flush_pending_stmts /* flush_pending_stmts */
6853 /* Split all critical edges. */
6856 split_critical_edges (void)
6862 /* split_edge can redirect edges out of SWITCH_EXPRs, which can get
6863 expensive. So we want to enable recording of edge to CASE_LABEL_EXPR
6864 mappings around the calls to split_edge. */
6865 start_recording_case_labels ();
6868 FOR_EACH_EDGE (e, ei, bb->succs)
6869 if (EDGE_CRITICAL_P (e) && !(e->flags & EDGE_ABNORMAL))
6874 end_recording_case_labels ();
6878 struct tree_opt_pass pass_split_crit_edges =
6880 "crited", /* name */
6882 split_critical_edges, /* execute */
6885 0, /* static_pass_number */
6886 TV_TREE_SPLIT_EDGES, /* tv_id */
6887 PROP_cfg, /* properties required */
6888 PROP_no_crit_edges, /* properties_provided */
6889 0, /* properties_destroyed */
6890 0, /* todo_flags_start */
6891 TODO_dump_func, /* todo_flags_finish */
6896 /* Return EXP if it is a valid GIMPLE rvalue, else gimplify it into
6897 a temporary, make sure and register it to be renamed if necessary,
6898 and finally return the temporary. Put the statements to compute
6899 EXP before the current statement in BSI. */
6902 gimplify_val (block_stmt_iterator *bsi, tree type, tree exp)
6904 tree t, new_stmt, orig_stmt;
6906 if (is_gimple_val (exp))
6909 t = make_rename_temp (type, NULL);
6910 new_stmt = build_gimple_modify_stmt (t, exp);
6912 orig_stmt = bsi_stmt (*bsi);
6913 SET_EXPR_LOCUS (new_stmt, EXPR_LOCUS (orig_stmt));
6914 TREE_BLOCK (new_stmt) = TREE_BLOCK (orig_stmt);
6916 bsi_insert_before (bsi, new_stmt, BSI_SAME_STMT);
6917 if (gimple_in_ssa_p (cfun))
6918 mark_symbols_for_renaming (new_stmt);
6923 /* Build a ternary operation and gimplify it. Emit code before BSI.
6924 Return the gimple_val holding the result. */
6927 gimplify_build3 (block_stmt_iterator *bsi, enum tree_code code,
6928 tree type, tree a, tree b, tree c)
6932 ret = fold_build3 (code, type, a, b, c);
6935 return gimplify_val (bsi, type, ret);
6938 /* Build a binary operation and gimplify it. Emit code before BSI.
6939 Return the gimple_val holding the result. */
6942 gimplify_build2 (block_stmt_iterator *bsi, enum tree_code code,
6943 tree type, tree a, tree b)
6947 ret = fold_build2 (code, type, a, b);
6950 return gimplify_val (bsi, type, ret);
6953 /* Build a unary operation and gimplify it. Emit code before BSI.
6954 Return the gimple_val holding the result. */
6957 gimplify_build1 (block_stmt_iterator *bsi, enum tree_code code, tree type,
6962 ret = fold_build1 (code, type, a);
6965 return gimplify_val (bsi, type, ret);
6970 /* Emit return warnings. */
6973 execute_warn_function_return (void)
6975 source_location location;
6980 /* If we have a path to EXIT, then we do return. */
6981 if (TREE_THIS_VOLATILE (cfun->decl)
6982 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0)
6984 location = UNKNOWN_LOCATION;
6985 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
6987 last = last_stmt (e->src);
6988 if (TREE_CODE (last) == RETURN_EXPR
6989 && (location = EXPR_LOCATION (last)) != UNKNOWN_LOCATION)
6992 if (location == UNKNOWN_LOCATION)
6993 location = cfun->function_end_locus;
6994 warning (0, "%H%<noreturn%> function does return", &location);
6997 /* If we see "return;" in some basic block, then we do reach the end
6998 without returning a value. */
6999 else if (warn_return_type
7000 && !TREE_NO_WARNING (cfun->decl)
7001 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0
7002 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (cfun->decl))))
7004 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7006 tree last = last_stmt (e->src);
7007 if (TREE_CODE (last) == RETURN_EXPR
7008 && TREE_OPERAND (last, 0) == NULL
7009 && !TREE_NO_WARNING (last))
7011 location = EXPR_LOCATION (last);
7012 if (location == UNKNOWN_LOCATION)
7013 location = cfun->function_end_locus;
7014 warning (OPT_Wreturn_type, "%Hcontrol reaches end of non-void function", &location);
7015 TREE_NO_WARNING (cfun->decl) = 1;
7024 /* Given a basic block B which ends with a conditional and has
7025 precisely two successors, determine which of the edges is taken if
7026 the conditional is true and which is taken if the conditional is
7027 false. Set TRUE_EDGE and FALSE_EDGE appropriately. */
7030 extract_true_false_edges_from_block (basic_block b,
7034 edge e = EDGE_SUCC (b, 0);
7036 if (e->flags & EDGE_TRUE_VALUE)
7039 *false_edge = EDGE_SUCC (b, 1);
7044 *true_edge = EDGE_SUCC (b, 1);
7048 struct tree_opt_pass pass_warn_function_return =
7052 execute_warn_function_return, /* execute */
7055 0, /* static_pass_number */
7057 PROP_cfg, /* properties_required */
7058 0, /* properties_provided */
7059 0, /* properties_destroyed */
7060 0, /* todo_flags_start */
7061 0, /* todo_flags_finish */
7065 /* Emit noreturn warnings. */
7068 execute_warn_function_noreturn (void)
7070 if (warn_missing_noreturn
7071 && !TREE_THIS_VOLATILE (cfun->decl)
7072 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0
7073 && !lang_hooks.function.missing_noreturn_ok_p (cfun->decl))
7074 warning (OPT_Wmissing_noreturn, "%Jfunction might be possible candidate "
7075 "for attribute %<noreturn%>",
7080 struct tree_opt_pass pass_warn_function_noreturn =
7084 execute_warn_function_noreturn, /* execute */
7087 0, /* static_pass_number */
7089 PROP_cfg, /* properties_required */
7090 0, /* properties_provided */
7091 0, /* properties_destroyed */
7092 0, /* todo_flags_start */
7093 0, /* todo_flags_finish */