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 GIMPLE_SWITCHes.
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 void make_blocks (gimple_seq);
87 static void factor_computed_gotos (void);
90 static void make_edges (void);
91 static void make_cond_expr_edges (basic_block);
92 static void make_gimple_switch_edges (basic_block);
93 static void make_goto_expr_edges (basic_block);
94 static edge gimple_redirect_edge_and_branch (edge, basic_block);
95 static edge gimple_try_redirect_by_replacing_jump (edge, basic_block);
96 static unsigned int split_critical_edges (void);
98 /* Various helpers. */
99 static inline bool stmt_starts_bb_p (gimple, gimple);
100 static int gimple_verify_flow_info (void);
101 static void gimple_make_forwarder_block (edge);
102 static void gimple_cfg2vcg (FILE *);
104 /* Flowgraph optimization and cleanup. */
105 static void gimple_merge_blocks (basic_block, basic_block);
106 static bool gimple_can_merge_blocks_p (basic_block, basic_block);
107 static void remove_bb (basic_block);
108 static edge find_taken_edge_computed_goto (basic_block, tree);
109 static edge find_taken_edge_cond_expr (basic_block, tree);
110 static edge find_taken_edge_switch_expr (basic_block, tree);
111 static tree find_case_label_for_value (gimple, tree);
114 init_empty_tree_cfg_for_function (struct function *fn)
116 /* Initialize the basic block array. */
118 profile_status_for_function (fn) = PROFILE_ABSENT;
119 n_basic_blocks_for_function (fn) = NUM_FIXED_BLOCKS;
120 last_basic_block_for_function (fn) = NUM_FIXED_BLOCKS;
121 basic_block_info_for_function (fn)
122 = VEC_alloc (basic_block, gc, initial_cfg_capacity);
123 VEC_safe_grow_cleared (basic_block, gc,
124 basic_block_info_for_function (fn),
125 initial_cfg_capacity);
127 /* Build a mapping of labels to their associated blocks. */
128 label_to_block_map_for_function (fn)
129 = VEC_alloc (basic_block, gc, initial_cfg_capacity);
130 VEC_safe_grow_cleared (basic_block, gc,
131 label_to_block_map_for_function (fn),
132 initial_cfg_capacity);
134 SET_BASIC_BLOCK_FOR_FUNCTION (fn, ENTRY_BLOCK,
135 ENTRY_BLOCK_PTR_FOR_FUNCTION (fn));
136 SET_BASIC_BLOCK_FOR_FUNCTION (fn, EXIT_BLOCK,
137 EXIT_BLOCK_PTR_FOR_FUNCTION (fn));
139 ENTRY_BLOCK_PTR_FOR_FUNCTION (fn)->next_bb
140 = EXIT_BLOCK_PTR_FOR_FUNCTION (fn);
141 EXIT_BLOCK_PTR_FOR_FUNCTION (fn)->prev_bb
142 = ENTRY_BLOCK_PTR_FOR_FUNCTION (fn);
146 init_empty_tree_cfg (void)
148 init_empty_tree_cfg_for_function (cfun);
151 /*---------------------------------------------------------------------------
153 ---------------------------------------------------------------------------*/
155 /* Entry point to the CFG builder for trees. SEQ is the sequence of
156 statements to be added to the flowgraph. */
159 build_gimple_cfg (gimple_seq seq)
161 /* Register specific gimple functions. */
162 gimple_register_cfg_hooks ();
164 memset ((void *) &cfg_stats, 0, sizeof (cfg_stats));
166 init_empty_tree_cfg ();
168 found_computed_goto = 0;
171 /* Computed gotos are hell to deal with, especially if there are
172 lots of them with a large number of destinations. So we factor
173 them to a common computed goto location before we build the
174 edge list. After we convert back to normal form, we will un-factor
175 the computed gotos since factoring introduces an unwanted jump. */
176 if (found_computed_goto)
177 factor_computed_gotos ();
179 /* Make sure there is always at least one block, even if it's empty. */
180 if (n_basic_blocks == NUM_FIXED_BLOCKS)
181 create_empty_bb (ENTRY_BLOCK_PTR);
183 /* Adjust the size of the array. */
184 if (VEC_length (basic_block, basic_block_info) < (size_t) n_basic_blocks)
185 VEC_safe_grow_cleared (basic_block, gc, basic_block_info, n_basic_blocks);
187 /* To speed up statement iterator walks, we first purge dead labels. */
188 cleanup_dead_labels ();
190 /* Group case nodes to reduce the number of edges.
191 We do this after cleaning up dead labels because otherwise we miss
192 a lot of obvious case merging opportunities. */
193 group_case_labels ();
195 /* Create the edges of the flowgraph. */
197 cleanup_dead_labels ();
199 /* Debugging dumps. */
201 /* Write the flowgraph to a VCG file. */
203 int local_dump_flags;
204 FILE *vcg_file = dump_begin (TDI_vcg, &local_dump_flags);
207 gimple_cfg2vcg (vcg_file);
208 dump_end (TDI_vcg, vcg_file);
212 #ifdef ENABLE_CHECKING
218 execute_build_cfg (void)
220 gimple_seq body = gimple_body (current_function_decl);
222 build_gimple_cfg (body);
223 gimple_set_body (current_function_decl, NULL);
227 struct gimple_opt_pass pass_build_cfg =
233 execute_build_cfg, /* execute */
236 0, /* static_pass_number */
237 TV_TREE_CFG, /* tv_id */
238 PROP_gimple_leh, /* properties_required */
239 PROP_cfg, /* properties_provided */
240 0, /* properties_destroyed */
241 0, /* todo_flags_start */
242 TODO_verify_stmts | TODO_cleanup_cfg
243 | TODO_dump_func /* todo_flags_finish */
248 /* Return true if T is a computed goto. */
251 computed_goto_p (gimple t)
253 return (gimple_code (t) == GIMPLE_GOTO
254 && TREE_CODE (gimple_goto_dest (t)) != LABEL_DECL);
258 /* Search the CFG for any computed gotos. If found, factor them to a
259 common computed goto site. Also record the location of that site so
260 that we can un-factor the gotos after we have converted back to
264 factor_computed_gotos (void)
267 tree factored_label_decl = NULL;
269 gimple factored_computed_goto_label = NULL;
270 gimple factored_computed_goto = NULL;
272 /* We know there are one or more computed gotos in this function.
273 Examine the last statement in each basic block to see if the block
274 ends with a computed goto. */
278 gimple_stmt_iterator gsi = gsi_last_bb (bb);
284 last = gsi_stmt (gsi);
286 /* Ignore the computed goto we create when we factor the original
288 if (last == factored_computed_goto)
291 /* If the last statement is a computed goto, factor it. */
292 if (computed_goto_p (last))
296 /* The first time we find a computed goto we need to create
297 the factored goto block and the variable each original
298 computed goto will use for their goto destination. */
299 if (!factored_computed_goto)
301 basic_block new_bb = create_empty_bb (bb);
302 gimple_stmt_iterator new_gsi = gsi_start_bb (new_bb);
304 /* Create the destination of the factored goto. Each original
305 computed goto will put its desired destination into this
306 variable and jump to the label we create immediately
308 var = create_tmp_var (ptr_type_node, "gotovar");
310 /* Build a label for the new block which will contain the
311 factored computed goto. */
312 factored_label_decl = create_artificial_label ();
313 factored_computed_goto_label
314 = gimple_build_label (factored_label_decl);
315 gsi_insert_after (&new_gsi, factored_computed_goto_label,
318 /* Build our new computed goto. */
319 factored_computed_goto = gimple_build_goto (var);
320 gsi_insert_after (&new_gsi, factored_computed_goto, GSI_NEW_STMT);
323 /* Copy the original computed goto's destination into VAR. */
324 assignment = gimple_build_assign (var, gimple_goto_dest (last));
325 gsi_insert_before (&gsi, assignment, GSI_SAME_STMT);
327 /* And re-vector the computed goto to the new destination. */
328 gimple_goto_set_dest (last, factored_label_decl);
334 /* Build a flowgraph for the sequence of stmts SEQ. */
337 make_blocks (gimple_seq seq)
339 gimple_stmt_iterator i = gsi_start (seq);
341 bool start_new_block = true;
342 bool first_stmt_of_seq = true;
343 basic_block bb = ENTRY_BLOCK_PTR;
345 while (!gsi_end_p (i))
352 /* If the statement starts a new basic block or if we have determined
353 in a previous pass that we need to create a new block for STMT, do
355 if (start_new_block || stmt_starts_bb_p (stmt, prev_stmt))
357 if (!first_stmt_of_seq)
358 seq = gsi_split_seq_before (&i);
359 bb = create_basic_block (seq, NULL, bb);
360 start_new_block = false;
363 /* Now add STMT to BB and create the subgraphs for special statement
365 gimple_set_bb (stmt, bb);
367 if (computed_goto_p (stmt))
368 found_computed_goto = true;
370 /* If STMT is a basic block terminator, set START_NEW_BLOCK for the
372 if (stmt_ends_bb_p (stmt))
373 start_new_block = true;
376 first_stmt_of_seq = false;
381 /* Create and return a new empty basic block after bb AFTER. */
384 create_bb (void *h, void *e, basic_block after)
390 /* Create and initialize a new basic block. Since alloc_block uses
391 ggc_alloc_cleared to allocate a basic block, we do not have to
392 clear the newly allocated basic block here. */
395 bb->index = last_basic_block;
397 bb->il.gimple = GGC_CNEW (struct gimple_bb_info);
398 set_bb_seq (bb, h ? (gimple_seq) h : gimple_seq_alloc ());
400 /* Add the new block to the linked list of blocks. */
401 link_block (bb, after);
403 /* Grow the basic block array if needed. */
404 if ((size_t) last_basic_block == VEC_length (basic_block, basic_block_info))
406 size_t new_size = last_basic_block + (last_basic_block + 3) / 4;
407 VEC_safe_grow_cleared (basic_block, gc, basic_block_info, new_size);
410 /* Add the newly created block to the array. */
411 SET_BASIC_BLOCK (last_basic_block, bb);
420 /*---------------------------------------------------------------------------
422 ---------------------------------------------------------------------------*/
424 /* Fold COND_EXPR_COND of each COND_EXPR. */
427 fold_cond_expr_cond (void)
433 gimple stmt = last_stmt (bb);
435 if (stmt && gimple_code (stmt) == GIMPLE_COND)
440 fold_defer_overflow_warnings ();
441 cond = fold_binary (gimple_cond_code (stmt), boolean_type_node,
442 gimple_cond_lhs (stmt), gimple_cond_rhs (stmt));
445 zerop = integer_zerop (cond);
446 onep = integer_onep (cond);
449 zerop = onep = false;
451 fold_undefer_overflow_warnings (zerop || onep,
453 WARN_STRICT_OVERFLOW_CONDITIONAL);
455 gimple_cond_make_false (stmt);
457 gimple_cond_make_true (stmt);
462 /* Join all the blocks in the flowgraph. */
468 struct omp_region *cur_region = NULL;
470 /* Create an edge from entry to the first block with executable
472 make_edge (ENTRY_BLOCK_PTR, BASIC_BLOCK (NUM_FIXED_BLOCKS), EDGE_FALLTHRU);
474 /* Traverse the basic block array placing edges. */
477 gimple last = last_stmt (bb);
482 enum gimple_code code = gimple_code (last);
486 make_goto_expr_edges (bb);
490 make_edge (bb, EXIT_BLOCK_PTR, 0);
494 make_cond_expr_edges (bb);
498 make_gimple_switch_edges (bb);
502 make_eh_edges (last);
507 /* If this function receives a nonlocal goto, then we need to
508 make edges from this call site to all the nonlocal goto
510 if (stmt_can_make_abnormal_goto (last))
511 make_abnormal_goto_edges (bb, true);
513 /* If this statement has reachable exception handlers, then
514 create abnormal edges to them. */
515 make_eh_edges (last);
517 /* Some calls are known not to return. */
518 fallthru = !(gimple_call_flags (last) & ECF_NORETURN);
522 /* A GIMPLE_ASSIGN may throw internally and thus be considered
524 if (is_ctrl_altering_stmt (last))
526 make_eh_edges (last);
531 case GIMPLE_OMP_PARALLEL:
532 case GIMPLE_OMP_TASK:
534 case GIMPLE_OMP_SINGLE:
535 case GIMPLE_OMP_MASTER:
536 case GIMPLE_OMP_ORDERED:
537 case GIMPLE_OMP_CRITICAL:
538 case GIMPLE_OMP_SECTION:
539 cur_region = new_omp_region (bb, code, cur_region);
543 case GIMPLE_OMP_SECTIONS:
544 cur_region = new_omp_region (bb, code, cur_region);
548 case GIMPLE_OMP_SECTIONS_SWITCH:
553 case GIMPLE_OMP_ATOMIC_LOAD:
554 case GIMPLE_OMP_ATOMIC_STORE:
559 case GIMPLE_OMP_RETURN:
560 /* In the case of a GIMPLE_OMP_SECTION, the edge will go
561 somewhere other than the next block. This will be
563 cur_region->exit = bb;
564 fallthru = cur_region->type != GIMPLE_OMP_SECTION;
565 cur_region = cur_region->outer;
568 case GIMPLE_OMP_CONTINUE:
569 cur_region->cont = bb;
570 switch (cur_region->type)
573 /* Mark all GIMPLE_OMP_FOR and GIMPLE_OMP_CONTINUE
574 succs edges as abnormal to prevent splitting
576 single_succ_edge (cur_region->entry)->flags |= EDGE_ABNORMAL;
577 /* Make the loopback edge. */
578 make_edge (bb, single_succ (cur_region->entry),
581 /* Create an edge from GIMPLE_OMP_FOR to exit, which
582 corresponds to the case that the body of the loop
583 is not executed at all. */
584 make_edge (cur_region->entry, bb->next_bb, EDGE_ABNORMAL);
585 make_edge (bb, bb->next_bb, EDGE_FALLTHRU | EDGE_ABNORMAL);
589 case GIMPLE_OMP_SECTIONS:
590 /* Wire up the edges into and out of the nested sections. */
592 basic_block switch_bb = single_succ (cur_region->entry);
594 struct omp_region *i;
595 for (i = cur_region->inner; i ; i = i->next)
597 gcc_assert (i->type == GIMPLE_OMP_SECTION);
598 make_edge (switch_bb, i->entry, 0);
599 make_edge (i->exit, bb, EDGE_FALLTHRU);
602 /* Make the loopback edge to the block with
603 GIMPLE_OMP_SECTIONS_SWITCH. */
604 make_edge (bb, switch_bb, 0);
606 /* Make the edge from the switch to exit. */
607 make_edge (switch_bb, bb->next_bb, 0);
618 gcc_assert (!stmt_ends_bb_p (last));
626 make_edge (bb, bb->next_bb, EDGE_FALLTHRU);
632 /* Fold COND_EXPR_COND of each COND_EXPR. */
633 fold_cond_expr_cond ();
637 /* Create the edges for a GIMPLE_COND starting at block BB. */
640 make_cond_expr_edges (basic_block bb)
642 gimple entry = last_stmt (bb);
643 gimple then_stmt, else_stmt;
644 basic_block then_bb, else_bb;
645 tree then_label, else_label;
649 gcc_assert (gimple_code (entry) == GIMPLE_COND);
651 /* Entry basic blocks for each component. */
652 then_label = gimple_cond_true_label (entry);
653 else_label = gimple_cond_false_label (entry);
654 then_bb = label_to_block (then_label);
655 else_bb = label_to_block (else_label);
656 then_stmt = first_stmt (then_bb);
657 else_stmt = first_stmt (else_bb);
659 e = make_edge (bb, then_bb, EDGE_TRUE_VALUE);
660 e->goto_locus = gimple_location (then_stmt);
661 e = make_edge (bb, else_bb, EDGE_FALSE_VALUE);
663 e->goto_locus = gimple_location (else_stmt);
665 /* We do not need the labels anymore. */
666 gimple_cond_set_true_label (entry, NULL_TREE);
667 gimple_cond_set_false_label (entry, NULL_TREE);
671 /* Called for each element in the hash table (P) as we delete the
672 edge to cases hash table.
674 Clear all the TREE_CHAINs to prevent problems with copying of
675 SWITCH_EXPRs and structure sharing rules, then free the hash table
679 edge_to_cases_cleanup (const void *key ATTRIBUTE_UNUSED, void **value,
680 void *data ATTRIBUTE_UNUSED)
684 for (t = (tree) *value; t; t = next)
686 next = TREE_CHAIN (t);
687 TREE_CHAIN (t) = NULL;
694 /* Start recording information mapping edges to case labels. */
697 start_recording_case_labels (void)
699 gcc_assert (edge_to_cases == NULL);
700 edge_to_cases = pointer_map_create ();
703 /* Return nonzero if we are recording information for case labels. */
706 recording_case_labels_p (void)
708 return (edge_to_cases != NULL);
711 /* Stop recording information mapping edges to case labels and
712 remove any information we have recorded. */
714 end_recording_case_labels (void)
716 pointer_map_traverse (edge_to_cases, edge_to_cases_cleanup, NULL);
717 pointer_map_destroy (edge_to_cases);
718 edge_to_cases = NULL;
721 /* If we are inside a {start,end}_recording_cases block, then return
722 a chain of CASE_LABEL_EXPRs from T which reference E.
724 Otherwise return NULL. */
727 get_cases_for_edge (edge e, gimple t)
732 /* If we are not recording cases, then we do not have CASE_LABEL_EXPR
733 chains available. Return NULL so the caller can detect this case. */
734 if (!recording_case_labels_p ())
737 slot = pointer_map_contains (edge_to_cases, e);
741 /* If we did not find E in the hash table, then this must be the first
742 time we have been queried for information about E & T. Add all the
743 elements from T to the hash table then perform the query again. */
745 n = gimple_switch_num_labels (t);
746 for (i = 0; i < n; i++)
748 tree elt = gimple_switch_label (t, i);
749 tree lab = CASE_LABEL (elt);
750 basic_block label_bb = label_to_block (lab);
751 edge this_edge = find_edge (e->src, label_bb);
753 /* Add it to the chain of CASE_LABEL_EXPRs referencing E, or create
755 slot = pointer_map_insert (edge_to_cases, this_edge);
756 TREE_CHAIN (elt) = (tree) *slot;
760 return (tree) *pointer_map_contains (edge_to_cases, e);
763 /* Create the edges for a GIMPLE_SWITCH starting at block BB. */
766 make_gimple_switch_edges (basic_block bb)
768 gimple entry = last_stmt (bb);
771 n = gimple_switch_num_labels (entry);
773 for (i = 0; i < n; ++i)
775 tree lab = CASE_LABEL (gimple_switch_label (entry, i));
776 basic_block label_bb = label_to_block (lab);
777 make_edge (bb, label_bb, 0);
782 /* Return the basic block holding label DEST. */
785 label_to_block_fn (struct function *ifun, tree dest)
787 int uid = LABEL_DECL_UID (dest);
789 /* We would die hard when faced by an undefined label. Emit a label to
790 the very first basic block. This will hopefully make even the dataflow
791 and undefined variable warnings quite right. */
792 if ((errorcount || sorrycount) && uid < 0)
794 gimple_stmt_iterator gsi = gsi_start_bb (BASIC_BLOCK (NUM_FIXED_BLOCKS));
797 stmt = gimple_build_label (dest);
798 gsi_insert_before (&gsi, stmt, GSI_NEW_STMT);
799 uid = LABEL_DECL_UID (dest);
801 if (VEC_length (basic_block, ifun->cfg->x_label_to_block_map)
802 <= (unsigned int) uid)
804 return VEC_index (basic_block, ifun->cfg->x_label_to_block_map, uid);
807 /* Create edges for an abnormal goto statement at block BB. If FOR_CALL
808 is true, the source statement is a CALL_EXPR instead of a GOTO_EXPR. */
811 make_abnormal_goto_edges (basic_block bb, bool for_call)
813 basic_block target_bb;
814 gimple_stmt_iterator gsi;
816 FOR_EACH_BB (target_bb)
817 for (gsi = gsi_start_bb (target_bb); !gsi_end_p (gsi); gsi_next (&gsi))
819 gimple label_stmt = gsi_stmt (gsi);
822 if (gimple_code (label_stmt) != GIMPLE_LABEL)
825 target = gimple_label_label (label_stmt);
827 /* Make an edge to every label block that has been marked as a
828 potential target for a computed goto or a non-local goto. */
829 if ((FORCED_LABEL (target) && !for_call)
830 || (DECL_NONLOCAL (target) && for_call))
832 make_edge (bb, target_bb, EDGE_ABNORMAL);
838 /* Create edges for a goto statement at block BB. */
841 make_goto_expr_edges (basic_block bb)
843 gimple_stmt_iterator last = gsi_last_bb (bb);
844 gimple goto_t = gsi_stmt (last);
846 /* A simple GOTO creates normal edges. */
847 if (simple_goto_p (goto_t))
849 tree dest = gimple_goto_dest (goto_t);
850 edge e = make_edge (bb, label_to_block (dest), EDGE_FALLTHRU);
851 e->goto_locus = gimple_location (goto_t);
852 gsi_remove (&last, true);
856 /* A computed GOTO creates abnormal edges. */
857 make_abnormal_goto_edges (bb, false);
861 /*---------------------------------------------------------------------------
863 ---------------------------------------------------------------------------*/
865 /* Cleanup useless labels in basic blocks. This is something we wish
866 to do early because it allows us to group case labels before creating
867 the edges for the CFG, and it speeds up block statement iterators in
869 We rerun this pass after CFG is created, to get rid of the labels that
870 are no longer referenced. After then we do not run it any more, since
871 (almost) no new labels should be created. */
873 /* A map from basic block index to the leading label of that block. */
874 static struct label_record
879 /* True if the label is referenced from somewhere. */
883 /* Callback for for_each_eh_region. Helper for cleanup_dead_labels. */
885 update_eh_label (struct eh_region *region)
887 tree old_label = get_eh_region_tree_label (region);
891 basic_block bb = label_to_block (old_label);
893 /* ??? After optimizing, there may be EH regions with labels
894 that have already been removed from the function body, so
895 there is no basic block for them. */
899 new_label = label_for_bb[bb->index].label;
900 label_for_bb[bb->index].used = true;
901 set_eh_region_tree_label (region, new_label);
906 /* Given LABEL return the first label in the same basic block. */
909 main_block_label (tree label)
911 basic_block bb = label_to_block (label);
912 tree main_label = label_for_bb[bb->index].label;
914 /* label_to_block possibly inserted undefined label into the chain. */
917 label_for_bb[bb->index].label = label;
921 label_for_bb[bb->index].used = true;
925 /* Cleanup redundant labels. This is a three-step process:
926 1) Find the leading label for each block.
927 2) Redirect all references to labels to the leading labels.
928 3) Cleanup all useless labels. */
931 cleanup_dead_labels (void)
934 label_for_bb = XCNEWVEC (struct label_record, last_basic_block);
936 /* Find a suitable label for each block. We use the first user-defined
937 label if there is one, or otherwise just the first label we see. */
940 gimple_stmt_iterator i;
942 for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
945 gimple stmt = gsi_stmt (i);
947 if (gimple_code (stmt) != GIMPLE_LABEL)
950 label = gimple_label_label (stmt);
952 /* If we have not yet seen a label for the current block,
953 remember this one and see if there are more labels. */
954 if (!label_for_bb[bb->index].label)
956 label_for_bb[bb->index].label = label;
960 /* If we did see a label for the current block already, but it
961 is an artificially created label, replace it if the current
962 label is a user defined label. */
963 if (!DECL_ARTIFICIAL (label)
964 && DECL_ARTIFICIAL (label_for_bb[bb->index].label))
966 label_for_bb[bb->index].label = label;
972 /* Now redirect all jumps/branches to the selected label.
973 First do so for each block ending in a control statement. */
976 gimple stmt = last_stmt (bb);
980 switch (gimple_code (stmt))
984 tree true_label = gimple_cond_true_label (stmt);
985 tree false_label = gimple_cond_false_label (stmt);
988 gimple_cond_set_true_label (stmt, main_block_label (true_label));
990 gimple_cond_set_false_label (stmt, main_block_label (false_label));
996 size_t i, n = gimple_switch_num_labels (stmt);
998 /* Replace all destination labels. */
999 for (i = 0; i < n; ++i)
1001 tree case_label = gimple_switch_label (stmt, i);
1002 tree label = main_block_label (CASE_LABEL (case_label));
1003 CASE_LABEL (case_label) = label;
1008 /* We have to handle gotos until they're removed, and we don't
1009 remove them until after we've created the CFG edges. */
1011 if (!computed_goto_p (stmt))
1013 tree new_dest = main_block_label (gimple_goto_dest (stmt));
1014 gimple_goto_set_dest (stmt, new_dest);
1023 for_each_eh_region (update_eh_label);
1025 /* Finally, purge dead labels. All user-defined labels and labels that
1026 can be the target of non-local gotos and labels which have their
1027 address taken are preserved. */
1030 gimple_stmt_iterator i;
1031 tree label_for_this_bb = label_for_bb[bb->index].label;
1033 if (!label_for_this_bb)
1036 /* If the main label of the block is unused, we may still remove it. */
1037 if (!label_for_bb[bb->index].used)
1038 label_for_this_bb = NULL;
1040 for (i = gsi_start_bb (bb); !gsi_end_p (i); )
1043 gimple stmt = gsi_stmt (i);
1045 if (gimple_code (stmt) != GIMPLE_LABEL)
1048 label = gimple_label_label (stmt);
1050 if (label == label_for_this_bb
1051 || !DECL_ARTIFICIAL (label)
1052 || DECL_NONLOCAL (label)
1053 || FORCED_LABEL (label))
1056 gsi_remove (&i, true);
1060 free (label_for_bb);
1063 /* Look for blocks ending in a multiway branch (a SWITCH_EXPR in GIMPLE),
1064 and scan the sorted vector of cases. Combine the ones jumping to the
1066 Eg. three separate entries 1: 2: 3: become one entry 1..3: */
1069 group_case_labels (void)
1075 gimple stmt = last_stmt (bb);
1076 if (stmt && gimple_code (stmt) == GIMPLE_SWITCH)
1078 int old_size = gimple_switch_num_labels (stmt);
1079 int i, j, new_size = old_size;
1080 tree default_case = NULL_TREE;
1081 tree default_label = NULL_TREE;
1084 /* The default label is always the first case in a switch
1085 statement after gimplification if it was not optimized
1087 if (!CASE_LOW (gimple_switch_default_label (stmt))
1088 && !CASE_HIGH (gimple_switch_default_label (stmt)))
1090 default_case = gimple_switch_default_label (stmt);
1091 default_label = CASE_LABEL (default_case);
1095 has_default = false;
1097 /* Look for possible opportunities to merge cases. */
1102 while (i < old_size)
1104 tree base_case, base_label, base_high;
1105 base_case = gimple_switch_label (stmt, i);
1107 gcc_assert (base_case);
1108 base_label = CASE_LABEL (base_case);
1110 /* Discard cases that have the same destination as the
1112 if (base_label == default_label)
1114 gimple_switch_set_label (stmt, i, NULL_TREE);
1120 base_high = CASE_HIGH (base_case)
1121 ? CASE_HIGH (base_case)
1122 : CASE_LOW (base_case);
1125 /* Try to merge case labels. Break out when we reach the end
1126 of the label vector or when we cannot merge the next case
1127 label with the current one. */
1128 while (i < old_size)
1130 tree merge_case = gimple_switch_label (stmt, i);
1131 tree merge_label = CASE_LABEL (merge_case);
1132 tree t = int_const_binop (PLUS_EXPR, base_high,
1133 integer_one_node, 1);
1135 /* Merge the cases if they jump to the same place,
1136 and their ranges are consecutive. */
1137 if (merge_label == base_label
1138 && tree_int_cst_equal (CASE_LOW (merge_case), t))
1140 base_high = CASE_HIGH (merge_case) ?
1141 CASE_HIGH (merge_case) : CASE_LOW (merge_case);
1142 CASE_HIGH (base_case) = base_high;
1143 gimple_switch_set_label (stmt, i, NULL_TREE);
1152 /* Compress the case labels in the label vector, and adjust the
1153 length of the vector. */
1154 for (i = 0, j = 0; i < new_size; i++)
1156 while (! gimple_switch_label (stmt, j))
1158 gimple_switch_set_label (stmt, i,
1159 gimple_switch_label (stmt, j++));
1162 gcc_assert (new_size <= old_size);
1163 gimple_switch_set_num_labels (stmt, new_size);
1168 /* Checks whether we can merge block B into block A. */
1171 gimple_can_merge_blocks_p (basic_block a, basic_block b)
1174 gimple_stmt_iterator gsi;
1177 if (!single_succ_p (a))
1180 if (single_succ_edge (a)->flags & EDGE_ABNORMAL)
1183 if (single_succ (a) != b)
1186 if (!single_pred_p (b))
1189 if (b == EXIT_BLOCK_PTR)
1192 /* If A ends by a statement causing exceptions or something similar, we
1193 cannot merge the blocks. */
1194 stmt = last_stmt (a);
1195 if (stmt && stmt_ends_bb_p (stmt))
1198 /* Do not allow a block with only a non-local label to be merged. */
1200 && gimple_code (stmt) == GIMPLE_LABEL
1201 && DECL_NONLOCAL (gimple_label_label (stmt)))
1204 /* It must be possible to eliminate all phi nodes in B. If ssa form
1205 is not up-to-date, we cannot eliminate any phis; however, if only
1206 some symbols as whole are marked for renaming, this is not a problem,
1207 as phi nodes for those symbols are irrelevant in updating anyway. */
1208 phis = phi_nodes (b);
1209 if (!gimple_seq_empty_p (phis))
1211 gimple_stmt_iterator i;
1213 if (name_mappings_registered_p ())
1216 for (i = gsi_start (phis); !gsi_end_p (i); gsi_next (&i))
1218 gimple phi = gsi_stmt (i);
1220 if (!is_gimple_reg (gimple_phi_result (phi))
1221 && !may_propagate_copy (gimple_phi_result (phi),
1222 gimple_phi_arg_def (phi, 0)))
1227 /* Do not remove user labels. */
1228 for (gsi = gsi_start_bb (b); !gsi_end_p (gsi); gsi_next (&gsi))
1230 stmt = gsi_stmt (gsi);
1231 if (gimple_code (stmt) != GIMPLE_LABEL)
1233 if (!DECL_ARTIFICIAL (gimple_label_label (stmt)))
1237 /* Protect the loop latches. */
1239 && b->loop_father->latch == b)
1245 /* Replaces all uses of NAME by VAL. */
1248 replace_uses_by (tree name, tree val)
1250 imm_use_iterator imm_iter;
1255 FOR_EACH_IMM_USE_STMT (stmt, imm_iter, name)
1257 if (gimple_code (stmt) != GIMPLE_PHI)
1258 push_stmt_changes (&stmt);
1260 FOR_EACH_IMM_USE_ON_STMT (use, imm_iter)
1262 replace_exp (use, val);
1264 if (gimple_code (stmt) == GIMPLE_PHI)
1266 e = gimple_phi_arg_edge (stmt, PHI_ARG_INDEX_FROM_USE (use));
1267 if (e->flags & EDGE_ABNORMAL)
1269 /* This can only occur for virtual operands, since
1270 for the real ones SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name))
1271 would prevent replacement. */
1272 gcc_assert (!is_gimple_reg (name));
1273 SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val) = 1;
1278 if (gimple_code (stmt) != GIMPLE_PHI)
1282 fold_stmt_inplace (stmt);
1283 if (cfgcleanup_altered_bbs)
1284 bitmap_set_bit (cfgcleanup_altered_bbs, gimple_bb (stmt)->index);
1286 /* FIXME. This should go in pop_stmt_changes. */
1287 for (i = 0; i < gimple_num_ops (stmt); i++)
1289 tree op = gimple_op (stmt, i);
1290 /* Operands may be empty here. For example, the labels
1291 of a GIMPLE_COND are nulled out following the creation
1292 of the corresponding CFG edges. */
1293 if (op && TREE_CODE (op) == ADDR_EXPR)
1294 recompute_tree_invariant_for_addr_expr (op);
1297 maybe_clean_or_replace_eh_stmt (stmt, stmt);
1299 pop_stmt_changes (&stmt);
1303 gcc_assert (has_zero_uses (name));
1305 /* Also update the trees stored in loop structures. */
1311 FOR_EACH_LOOP (li, loop, 0)
1313 substitute_in_loop_info (loop, name, val);
1318 /* Merge block B into block A. */
1321 gimple_merge_blocks (basic_block a, basic_block b)
1323 gimple_stmt_iterator last, gsi, psi;
1324 gimple_seq phis = phi_nodes (b);
1327 fprintf (dump_file, "Merging blocks %d and %d\n", a->index, b->index);
1329 /* Remove all single-valued PHI nodes from block B of the form
1330 V_i = PHI <V_j> by propagating V_j to all the uses of V_i. */
1331 gsi = gsi_last_bb (a);
1332 for (psi = gsi_start (phis); !gsi_end_p (psi); )
1334 gimple phi = gsi_stmt (psi);
1335 tree def = gimple_phi_result (phi), use = gimple_phi_arg_def (phi, 0);
1337 bool may_replace_uses = !is_gimple_reg (def)
1338 || may_propagate_copy (def, use);
1340 /* In case we maintain loop closed ssa form, do not propagate arguments
1341 of loop exit phi nodes. */
1343 && loops_state_satisfies_p (LOOP_CLOSED_SSA)
1344 && is_gimple_reg (def)
1345 && TREE_CODE (use) == SSA_NAME
1346 && a->loop_father != b->loop_father)
1347 may_replace_uses = false;
1349 if (!may_replace_uses)
1351 gcc_assert (is_gimple_reg (def));
1353 /* Note that just emitting the copies is fine -- there is no problem
1354 with ordering of phi nodes. This is because A is the single
1355 predecessor of B, therefore results of the phi nodes cannot
1356 appear as arguments of the phi nodes. */
1357 copy = gimple_build_assign (def, use);
1358 gsi_insert_after (&gsi, copy, GSI_NEW_STMT);
1359 remove_phi_node (&psi, false);
1363 /* If we deal with a PHI for virtual operands, we can simply
1364 propagate these without fussing with folding or updating
1366 if (!is_gimple_reg (def))
1368 imm_use_iterator iter;
1369 use_operand_p use_p;
1372 FOR_EACH_IMM_USE_STMT (stmt, iter, def)
1373 FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
1374 SET_USE (use_p, use);
1377 replace_uses_by (def, use);
1379 remove_phi_node (&psi, true);
1383 /* Ensure that B follows A. */
1384 move_block_after (b, a);
1386 gcc_assert (single_succ_edge (a)->flags & EDGE_FALLTHRU);
1387 gcc_assert (!last_stmt (a) || !stmt_ends_bb_p (last_stmt (a)));
1389 /* Remove labels from B and set gimple_bb to A for other statements. */
1390 for (gsi = gsi_start_bb (b); !gsi_end_p (gsi);)
1392 if (gimple_code (gsi_stmt (gsi)) == GIMPLE_LABEL)
1394 gimple label = gsi_stmt (gsi);
1396 gsi_remove (&gsi, false);
1398 /* Now that we can thread computed gotos, we might have
1399 a situation where we have a forced label in block B
1400 However, the label at the start of block B might still be
1401 used in other ways (think about the runtime checking for
1402 Fortran assigned gotos). So we can not just delete the
1403 label. Instead we move the label to the start of block A. */
1404 if (FORCED_LABEL (gimple_label_label (label)))
1406 gimple_stmt_iterator dest_gsi = gsi_start_bb (a);
1407 gsi_insert_before (&dest_gsi, label, GSI_NEW_STMT);
1412 gimple_set_bb (gsi_stmt (gsi), a);
1417 /* Merge the sequences. */
1418 last = gsi_last_bb (a);
1419 gsi_insert_seq_after (&last, bb_seq (b), GSI_NEW_STMT);
1420 set_bb_seq (b, NULL);
1422 if (cfgcleanup_altered_bbs)
1423 bitmap_set_bit (cfgcleanup_altered_bbs, a->index);
1427 /* Return the one of two successors of BB that is not reachable by a
1428 reached by a complex edge, if there is one. Else, return BB. We use
1429 this in optimizations that use post-dominators for their heuristics,
1430 to catch the cases in C++ where function calls are involved. */
1433 single_noncomplex_succ (basic_block bb)
1436 if (EDGE_COUNT (bb->succs) != 2)
1439 e0 = EDGE_SUCC (bb, 0);
1440 e1 = EDGE_SUCC (bb, 1);
1441 if (e0->flags & EDGE_COMPLEX)
1443 if (e1->flags & EDGE_COMPLEX)
1450 /* Walk the function tree removing unnecessary statements.
1452 * Empty statement nodes are removed
1454 * Unnecessary TRY_FINALLY and TRY_CATCH blocks are removed
1456 * Unnecessary COND_EXPRs are removed
1458 * Some unnecessary BIND_EXPRs are removed
1460 * GOTO_EXPRs immediately preceding destination are removed.
1462 Clearly more work could be done. The trick is doing the analysis
1463 and removal fast enough to be a net improvement in compile times.
1465 Note that when we remove a control structure such as a COND_EXPR
1466 BIND_EXPR, or TRY block, we will need to repeat this optimization pass
1467 to ensure we eliminate all the useless code. */
1476 gimple_stmt_iterator last_goto_gsi;
1480 static void remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *);
1482 /* Given a statement sequence, find the first executable statement with
1483 location information, and warn that it is unreachable. When searching,
1484 descend into containers in execution order. */
1487 remove_useless_stmts_warn_notreached (gimple_seq stmts)
1489 gimple_stmt_iterator gsi;
1491 for (gsi = gsi_start (stmts); !gsi_end_p (gsi); gsi_next (&gsi))
1493 gimple stmt = gsi_stmt (gsi);
1495 if (gimple_has_location (stmt))
1497 location_t loc = gimple_location (stmt);
1498 if (LOCATION_LINE (loc) > 0)
1500 warning (OPT_Wunreachable_code, "%Hwill never be executed", &loc);
1505 switch (gimple_code (stmt))
1507 /* Unfortunately, we need the CFG now to detect unreachable
1508 branches in a conditional, so conditionals are not handled here. */
1511 if (remove_useless_stmts_warn_notreached (gimple_try_eval (stmt)))
1513 if (remove_useless_stmts_warn_notreached (gimple_try_cleanup (stmt)))
1518 return remove_useless_stmts_warn_notreached (gimple_catch_handler (stmt));
1520 case GIMPLE_EH_FILTER:
1521 return remove_useless_stmts_warn_notreached (gimple_eh_filter_failure (stmt));
1524 return remove_useless_stmts_warn_notreached (gimple_bind_body (stmt));
1534 /* Helper for remove_useless_stmts_1. Handle GIMPLE_COND statements. */
1537 remove_useless_stmts_cond (gimple_stmt_iterator *gsi, struct rus_data *data)
1539 gimple stmt = gsi_stmt (*gsi);
1541 /* The folded result must still be a conditional statement. */
1542 fold_stmt_inplace (stmt);
1544 data->may_branch = true;
1546 /* Replace trivial conditionals with gotos. */
1547 if (gimple_cond_true_p (stmt))
1549 /* Goto THEN label. */
1550 tree then_label = gimple_cond_true_label (stmt);
1552 gsi_replace (gsi, gimple_build_goto (then_label), false);
1553 data->last_goto_gsi = *gsi;
1554 data->last_was_goto = true;
1555 data->repeat = true;
1557 else if (gimple_cond_false_p (stmt))
1559 /* Goto ELSE label. */
1560 tree else_label = gimple_cond_false_label (stmt);
1562 gsi_replace (gsi, gimple_build_goto (else_label), false);
1563 data->last_goto_gsi = *gsi;
1564 data->last_was_goto = true;
1565 data->repeat = true;
1569 tree then_label = gimple_cond_true_label (stmt);
1570 tree else_label = gimple_cond_false_label (stmt);
1572 if (then_label == else_label)
1574 /* Goto common destination. */
1575 gsi_replace (gsi, gimple_build_goto (then_label), false);
1576 data->last_goto_gsi = *gsi;
1577 data->last_was_goto = true;
1578 data->repeat = true;
1584 data->last_was_goto = false;
1587 /* Helper for remove_useless_stmts_1.
1588 Handle the try-finally case for GIMPLE_TRY statements. */
1591 remove_useless_stmts_tf (gimple_stmt_iterator *gsi, struct rus_data *data)
1593 bool save_may_branch, save_may_throw;
1594 bool this_may_branch, this_may_throw;
1596 gimple_seq eval_seq, cleanup_seq;
1597 gimple_stmt_iterator eval_gsi, cleanup_gsi;
1599 gimple stmt = gsi_stmt (*gsi);
1601 /* Collect may_branch and may_throw information for the body only. */
1602 save_may_branch = data->may_branch;
1603 save_may_throw = data->may_throw;
1604 data->may_branch = false;
1605 data->may_throw = false;
1606 data->last_was_goto = false;
1608 eval_seq = gimple_try_eval (stmt);
1609 eval_gsi = gsi_start (eval_seq);
1610 remove_useless_stmts_1 (&eval_gsi, data);
1612 this_may_branch = data->may_branch;
1613 this_may_throw = data->may_throw;
1614 data->may_branch |= save_may_branch;
1615 data->may_throw |= save_may_throw;
1616 data->last_was_goto = false;
1618 cleanup_seq = gimple_try_cleanup (stmt);
1619 cleanup_gsi = gsi_start (cleanup_seq);
1620 remove_useless_stmts_1 (&cleanup_gsi, data);
1622 /* If the body is empty, then we can emit the FINALLY block without
1623 the enclosing TRY_FINALLY_EXPR. */
1624 if (gimple_seq_empty_p (eval_seq))
1626 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1627 gsi_remove (gsi, false);
1628 data->repeat = true;
1631 /* If the handler is empty, then we can emit the TRY block without
1632 the enclosing TRY_FINALLY_EXPR. */
1633 else if (gimple_seq_empty_p (cleanup_seq))
1635 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1636 gsi_remove (gsi, false);
1637 data->repeat = true;
1640 /* If the body neither throws, nor branches, then we can safely
1641 string the TRY and FINALLY blocks together. */
1642 else if (!this_may_branch && !this_may_throw)
1644 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1645 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1646 gsi_remove (gsi, false);
1647 data->repeat = true;
1653 /* Helper for remove_useless_stmts_1.
1654 Handle the try-catch case for GIMPLE_TRY statements. */
1657 remove_useless_stmts_tc (gimple_stmt_iterator *gsi, struct rus_data *data)
1659 bool save_may_throw, this_may_throw;
1661 gimple_seq eval_seq, cleanup_seq, handler_seq, failure_seq;
1662 gimple_stmt_iterator eval_gsi, cleanup_gsi, handler_gsi, failure_gsi;
1664 gimple stmt = gsi_stmt (*gsi);
1666 /* Collect may_throw information for the body only. */
1667 save_may_throw = data->may_throw;
1668 data->may_throw = false;
1669 data->last_was_goto = false;
1671 eval_seq = gimple_try_eval (stmt);
1672 eval_gsi = gsi_start (eval_seq);
1673 remove_useless_stmts_1 (&eval_gsi, data);
1675 this_may_throw = data->may_throw;
1676 data->may_throw = save_may_throw;
1678 cleanup_seq = gimple_try_cleanup (stmt);
1680 /* If the body cannot throw, then we can drop the entire TRY_CATCH_EXPR. */
1681 if (!this_may_throw)
1683 if (warn_notreached)
1685 remove_useless_stmts_warn_notreached (cleanup_seq);
1687 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1688 gsi_remove (gsi, false);
1689 data->repeat = true;
1693 /* Process the catch clause specially. We may be able to tell that
1694 no exceptions propagate past this point. */
1696 this_may_throw = true;
1697 cleanup_gsi = gsi_start (cleanup_seq);
1698 stmt = gsi_stmt (cleanup_gsi);
1699 data->last_was_goto = false;
1701 switch (gimple_code (stmt))
1704 /* If the first element is a catch, they all must be. */
1705 while (!gsi_end_p (cleanup_gsi))
1707 stmt = gsi_stmt (cleanup_gsi);
1708 /* If we catch all exceptions, then the body does not
1709 propagate exceptions past this point. */
1710 if (gimple_catch_types (stmt) == NULL)
1711 this_may_throw = false;
1712 data->last_was_goto = false;
1713 handler_seq = gimple_catch_handler (stmt);
1714 handler_gsi = gsi_start (handler_seq);
1715 remove_useless_stmts_1 (&handler_gsi, data);
1716 gsi_next (&cleanup_gsi);
1721 case GIMPLE_EH_FILTER:
1722 /* If the first element is an eh_filter, it should stand alone. */
1723 if (gimple_eh_filter_must_not_throw (stmt))
1724 this_may_throw = false;
1725 else if (gimple_eh_filter_types (stmt) == NULL)
1726 this_may_throw = false;
1727 failure_seq = gimple_eh_filter_failure (stmt);
1728 failure_gsi = gsi_start (failure_seq);
1729 remove_useless_stmts_1 (&failure_gsi, data);
1734 /* Otherwise this is a list of cleanup statements. */
1735 remove_useless_stmts_1 (&cleanup_gsi, data);
1737 /* If the cleanup is empty, then we can emit the TRY block without
1738 the enclosing TRY_CATCH_EXPR. */
1739 if (gimple_seq_empty_p (cleanup_seq))
1741 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1742 gsi_remove(gsi, false);
1743 data->repeat = true;
1750 data->may_throw |= this_may_throw;
1753 /* Helper for remove_useless_stmts_1. Handle GIMPLE_BIND statements. */
1756 remove_useless_stmts_bind (gimple_stmt_iterator *gsi, struct rus_data *data ATTRIBUTE_UNUSED)
1759 gimple_seq body_seq, fn_body_seq;
1760 gimple_stmt_iterator body_gsi;
1762 gimple stmt = gsi_stmt (*gsi);
1764 /* First remove anything underneath the BIND_EXPR. */
1766 body_seq = gimple_bind_body (stmt);
1767 body_gsi = gsi_start (body_seq);
1768 remove_useless_stmts_1 (&body_gsi, data);
1770 /* If the GIMPLE_BIND has no variables, then we can pull everything
1771 up one level and remove the GIMPLE_BIND, unless this is the toplevel
1772 GIMPLE_BIND for the current function or an inlined function.
1774 When this situation occurs we will want to apply this
1775 optimization again. */
1776 block = gimple_bind_block (stmt);
1777 fn_body_seq = gimple_body (current_function_decl);
1778 if (gimple_bind_vars (stmt) == NULL_TREE
1779 && (gimple_seq_empty_p (fn_body_seq)
1780 || stmt != gimple_seq_first_stmt (fn_body_seq))
1782 || ! BLOCK_ABSTRACT_ORIGIN (block)
1783 || (TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block))
1786 gsi_insert_seq_before (gsi, body_seq, GSI_SAME_STMT);
1787 gsi_remove (gsi, false);
1788 data->repeat = true;
1794 /* Helper for remove_useless_stmts_1. Handle GIMPLE_GOTO statements. */
1797 remove_useless_stmts_goto (gimple_stmt_iterator *gsi, struct rus_data *data)
1799 gimple stmt = gsi_stmt (*gsi);
1801 tree dest = gimple_goto_dest (stmt);
1803 data->may_branch = true;
1804 data->last_was_goto = false;
1806 /* Record iterator for last goto expr, so that we can delete it if unnecessary. */
1807 if (TREE_CODE (dest) == LABEL_DECL)
1809 data->last_goto_gsi = *gsi;
1810 data->last_was_goto = true;
1816 /* Helper for remove_useless_stmts_1. Handle GIMPLE_LABEL statements. */
1819 remove_useless_stmts_label (gimple_stmt_iterator *gsi, struct rus_data *data)
1821 gimple stmt = gsi_stmt (*gsi);
1823 tree label = gimple_label_label (stmt);
1825 data->has_label = true;
1827 /* We do want to jump across non-local label receiver code. */
1828 if (DECL_NONLOCAL (label))
1829 data->last_was_goto = false;
1831 else if (data->last_was_goto
1832 && gimple_goto_dest (gsi_stmt (data->last_goto_gsi)) == label)
1834 /* Replace the preceding GIMPLE_GOTO statement with
1835 a GIMPLE_NOP, which will be subsequently removed.
1836 In this way, we avoid invalidating other iterators
1837 active on the statement sequence. */
1838 gsi_replace(&data->last_goto_gsi, gimple_build_nop(), false);
1839 data->last_was_goto = false;
1840 data->repeat = true;
1843 /* ??? Add something here to delete unused labels. */
1849 /* T is CALL_EXPR. Set current_function_calls_* flags. */
1852 notice_special_calls (gimple call)
1854 int flags = gimple_call_flags (call);
1856 if (flags & ECF_MAY_BE_ALLOCA)
1857 cfun->calls_alloca = true;
1858 if (flags & ECF_RETURNS_TWICE)
1859 cfun->calls_setjmp = true;
1863 /* Clear flags set by notice_special_calls. Used by dead code removal
1864 to update the flags. */
1867 clear_special_calls (void)
1869 cfun->calls_alloca = false;
1870 cfun->calls_setjmp = false;
1873 /* Remove useless statements from a statement sequence, and perform
1874 some preliminary simplifications. */
1877 remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *data)
1879 while (!gsi_end_p (*gsi))
1881 gimple stmt = gsi_stmt (*gsi);
1883 switch (gimple_code (stmt))
1886 remove_useless_stmts_cond (gsi, data);
1890 remove_useless_stmts_goto (gsi, data);
1894 remove_useless_stmts_label (gsi, data);
1899 stmt = gsi_stmt (*gsi);
1900 data->last_was_goto = false;
1901 if (stmt_could_throw_p (stmt))
1902 data->may_throw = true;
1908 data->last_was_goto = false;
1914 stmt = gsi_stmt (*gsi);
1915 data->last_was_goto = false;
1916 if (is_gimple_call (stmt))
1917 notice_special_calls (stmt);
1919 /* We used to call update_gimple_call_flags here,
1920 which copied side-effects and nothrows status
1921 from the function decl to the call. In the new
1922 tuplified GIMPLE, the accessors for this information
1923 always consult the function decl, so this copying
1924 is no longer necessary. */
1925 if (stmt_could_throw_p (stmt))
1926 data->may_throw = true;
1932 data->last_was_goto = false;
1933 data->may_branch = true;
1938 remove_useless_stmts_bind (gsi, data);
1942 if (gimple_try_kind (stmt) == GIMPLE_TRY_CATCH)
1943 remove_useless_stmts_tc (gsi, data);
1944 else if (gimple_try_kind (stmt) == GIMPLE_TRY_FINALLY)
1945 remove_useless_stmts_tf (gsi, data);
1955 gsi_remove (gsi, false);
1958 case GIMPLE_OMP_FOR:
1960 gimple_seq pre_body_seq = gimple_omp_for_pre_body (stmt);
1961 gimple_stmt_iterator pre_body_gsi = gsi_start (pre_body_seq);
1963 remove_useless_stmts_1 (&pre_body_gsi, data);
1964 data->last_was_goto = false;
1967 case GIMPLE_OMP_CRITICAL:
1968 case GIMPLE_OMP_CONTINUE:
1969 case GIMPLE_OMP_MASTER:
1970 case GIMPLE_OMP_ORDERED:
1971 case GIMPLE_OMP_SECTION:
1972 case GIMPLE_OMP_SECTIONS:
1973 case GIMPLE_OMP_SINGLE:
1975 gimple_seq body_seq = gimple_omp_body (stmt);
1976 gimple_stmt_iterator body_gsi = gsi_start (body_seq);
1978 remove_useless_stmts_1 (&body_gsi, data);
1979 data->last_was_goto = false;
1984 case GIMPLE_OMP_PARALLEL:
1985 case GIMPLE_OMP_TASK:
1987 /* Make sure the outermost GIMPLE_BIND isn't removed
1989 gimple_seq body_seq = gimple_omp_body (stmt);
1990 gimple bind = gimple_seq_first_stmt (body_seq);
1991 gimple_seq bind_seq = gimple_bind_body (bind);
1992 gimple_stmt_iterator bind_gsi = gsi_start (bind_seq);
1994 remove_useless_stmts_1 (&bind_gsi, data);
1995 data->last_was_goto = false;
2001 data->last_was_goto = false;
2008 /* Walk the function tree, removing useless statements and performing
2009 some preliminary simplifications. */
2012 remove_useless_stmts (void)
2014 struct rus_data data;
2016 clear_special_calls ();
2020 gimple_stmt_iterator gsi;
2022 gsi = gsi_start (gimple_body (current_function_decl));
2023 memset (&data, 0, sizeof (data));
2024 remove_useless_stmts_1 (&gsi, &data);
2026 while (data.repeat);
2031 struct gimple_opt_pass pass_remove_useless_stmts =
2035 "useless", /* name */
2037 remove_useless_stmts, /* execute */
2040 0, /* static_pass_number */
2042 PROP_gimple_any, /* properties_required */
2043 0, /* properties_provided */
2044 0, /* properties_destroyed */
2045 0, /* todo_flags_start */
2046 TODO_dump_func /* todo_flags_finish */
2050 /* Remove PHI nodes associated with basic block BB and all edges out of BB. */
2053 remove_phi_nodes_and_edges_for_unreachable_block (basic_block bb)
2055 gimple_stmt_iterator gsi;
2057 /* Since this block is no longer reachable, we can just delete all
2058 of its PHI nodes. */
2059 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); )
2060 remove_phi_node (&gsi, true);
2062 set_phi_nodes (bb, NULL);
2064 /* Remove edges to BB's successors. */
2065 while (EDGE_COUNT (bb->succs) > 0)
2066 remove_edge (EDGE_SUCC (bb, 0));
2070 /* Remove statements of basic block BB. */
2073 remove_bb (basic_block bb)
2075 gimple_stmt_iterator i;
2076 source_location loc = UNKNOWN_LOCATION;
2080 fprintf (dump_file, "Removing basic block %d\n", bb->index);
2081 if (dump_flags & TDF_DETAILS)
2083 dump_bb (bb, dump_file, 0);
2084 fprintf (dump_file, "\n");
2090 struct loop *loop = bb->loop_father;
2092 /* If a loop gets removed, clean up the information associated
2094 if (loop->latch == bb
2095 || loop->header == bb)
2096 free_numbers_of_iterations_estimates_loop (loop);
2099 /* Remove all the instructions in the block. */
2100 if (bb_seq (bb) != NULL)
2102 for (i = gsi_start_bb (bb); !gsi_end_p (i);)
2104 gimple stmt = gsi_stmt (i);
2105 if (gimple_code (stmt) == GIMPLE_LABEL
2106 && (FORCED_LABEL (gimple_label_label (stmt))
2107 || DECL_NONLOCAL (gimple_label_label (stmt))))
2110 gimple_stmt_iterator new_gsi;
2112 /* A non-reachable non-local label may still be referenced.
2113 But it no longer needs to carry the extra semantics of
2115 if (DECL_NONLOCAL (gimple_label_label (stmt)))
2117 DECL_NONLOCAL (gimple_label_label (stmt)) = 0;
2118 FORCED_LABEL (gimple_label_label (stmt)) = 1;
2121 new_bb = bb->prev_bb;
2122 new_gsi = gsi_start_bb (new_bb);
2123 gsi_remove (&i, false);
2124 gsi_insert_before (&new_gsi, stmt, GSI_NEW_STMT);
2128 /* Release SSA definitions if we are in SSA. Note that we
2129 may be called when not in SSA. For example,
2130 final_cleanup calls this function via
2131 cleanup_tree_cfg. */
2132 if (gimple_in_ssa_p (cfun))
2133 release_defs (stmt);
2135 gsi_remove (&i, true);
2138 /* Don't warn for removed gotos. Gotos are often removed due to
2139 jump threading, thus resulting in bogus warnings. Not great,
2140 since this way we lose warnings for gotos in the original
2141 program that are indeed unreachable. */
2142 if (gimple_code (stmt) != GIMPLE_GOTO
2143 && gimple_has_location (stmt)
2145 loc = gimple_location (stmt);
2149 /* If requested, give a warning that the first statement in the
2150 block is unreachable. We walk statements backwards in the
2151 loop above, so the last statement we process is the first statement
2153 if (loc > BUILTINS_LOCATION && LOCATION_LINE (loc) > 0)
2154 warning (OPT_Wunreachable_code, "%Hwill never be executed", &loc);
2156 remove_phi_nodes_and_edges_for_unreachable_block (bb);
2157 bb->il.gimple = NULL;
2161 /* Given a basic block BB ending with COND_EXPR or SWITCH_EXPR, and a
2162 predicate VAL, return the edge that will be taken out of the block.
2163 If VAL does not match a unique edge, NULL is returned. */
2166 find_taken_edge (basic_block bb, tree val)
2170 stmt = last_stmt (bb);
2173 gcc_assert (is_ctrl_stmt (stmt));
2178 if (!is_gimple_min_invariant (val))
2181 if (gimple_code (stmt) == GIMPLE_COND)
2182 return find_taken_edge_cond_expr (bb, val);
2184 if (gimple_code (stmt) == GIMPLE_SWITCH)
2185 return find_taken_edge_switch_expr (bb, val);
2187 if (computed_goto_p (stmt))
2189 /* Only optimize if the argument is a label, if the argument is
2190 not a label then we can not construct a proper CFG.
2192 It may be the case that we only need to allow the LABEL_REF to
2193 appear inside an ADDR_EXPR, but we also allow the LABEL_REF to
2194 appear inside a LABEL_EXPR just to be safe. */
2195 if ((TREE_CODE (val) == ADDR_EXPR || TREE_CODE (val) == LABEL_EXPR)
2196 && TREE_CODE (TREE_OPERAND (val, 0)) == LABEL_DECL)
2197 return find_taken_edge_computed_goto (bb, TREE_OPERAND (val, 0));
2204 /* Given a constant value VAL and the entry block BB to a GOTO_EXPR
2205 statement, determine which of the outgoing edges will be taken out of the
2206 block. Return NULL if either edge may be taken. */
2209 find_taken_edge_computed_goto (basic_block bb, tree val)
2214 dest = label_to_block (val);
2217 e = find_edge (bb, dest);
2218 gcc_assert (e != NULL);
2224 /* Given a constant value VAL and the entry block BB to a COND_EXPR
2225 statement, determine which of the two edges will be taken out of the
2226 block. Return NULL if either edge may be taken. */
2229 find_taken_edge_cond_expr (basic_block bb, tree val)
2231 edge true_edge, false_edge;
2233 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
2235 gcc_assert (TREE_CODE (val) == INTEGER_CST);
2236 return (integer_zerop (val) ? false_edge : true_edge);
2239 /* Given an INTEGER_CST VAL and the entry block BB to a SWITCH_EXPR
2240 statement, determine which edge will be taken out of the block. Return
2241 NULL if any edge may be taken. */
2244 find_taken_edge_switch_expr (basic_block bb, tree val)
2246 basic_block dest_bb;
2251 switch_stmt = last_stmt (bb);
2252 taken_case = find_case_label_for_value (switch_stmt, val);
2253 dest_bb = label_to_block (CASE_LABEL (taken_case));
2255 e = find_edge (bb, dest_bb);
2261 /* Return the CASE_LABEL_EXPR that SWITCH_STMT will take for VAL.
2262 We can make optimal use here of the fact that the case labels are
2263 sorted: We can do a binary search for a case matching VAL. */
2266 find_case_label_for_value (gimple switch_stmt, tree val)
2268 size_t low, high, n = gimple_switch_num_labels (switch_stmt);
2269 tree default_case = gimple_switch_default_label (switch_stmt);
2271 for (low = 0, high = n; high - low > 1; )
2273 size_t i = (high + low) / 2;
2274 tree t = gimple_switch_label (switch_stmt, i);
2277 /* Cache the result of comparing CASE_LOW and val. */
2278 cmp = tree_int_cst_compare (CASE_LOW (t), val);
2285 if (CASE_HIGH (t) == NULL)
2287 /* A singe-valued case label. */
2293 /* A case range. We can only handle integer ranges. */
2294 if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
2299 return default_case;
2303 /* Dump a basic block on stderr. */
2306 gimple_debug_bb (basic_block bb)
2308 gimple_dump_bb (bb, stderr, 0, TDF_VOPS|TDF_MEMSYMS);
2312 /* Dump basic block with index N on stderr. */
2315 gimple_debug_bb_n (int n)
2317 gimple_debug_bb (BASIC_BLOCK (n));
2318 return BASIC_BLOCK (n);
2322 /* Dump the CFG on stderr.
2324 FLAGS are the same used by the tree dumping functions
2325 (see TDF_* in tree-pass.h). */
2328 gimple_debug_cfg (int flags)
2330 gimple_dump_cfg (stderr, flags);
2334 /* Dump the program showing basic block boundaries on the given FILE.
2336 FLAGS are the same used by the tree dumping functions (see TDF_* in
2340 gimple_dump_cfg (FILE *file, int flags)
2342 if (flags & TDF_DETAILS)
2344 const char *funcname
2345 = lang_hooks.decl_printable_name (current_function_decl, 2);
2348 fprintf (file, ";; Function %s\n\n", funcname);
2349 fprintf (file, ";; \n%d basic blocks, %d edges, last basic block %d.\n\n",
2350 n_basic_blocks, n_edges, last_basic_block);
2352 brief_dump_cfg (file);
2353 fprintf (file, "\n");
2356 if (flags & TDF_STATS)
2357 dump_cfg_stats (file);
2359 dump_function_to_file (current_function_decl, file, flags | TDF_BLOCKS);
2363 /* Dump CFG statistics on FILE. */
2366 dump_cfg_stats (FILE *file)
2368 static long max_num_merged_labels = 0;
2369 unsigned long size, total = 0;
2372 const char * const fmt_str = "%-30s%-13s%12s\n";
2373 const char * const fmt_str_1 = "%-30s%13d%11lu%c\n";
2374 const char * const fmt_str_2 = "%-30s%13ld%11lu%c\n";
2375 const char * const fmt_str_3 = "%-43s%11lu%c\n";
2376 const char *funcname
2377 = lang_hooks.decl_printable_name (current_function_decl, 2);
2380 fprintf (file, "\nCFG Statistics for %s\n\n", funcname);
2382 fprintf (file, "---------------------------------------------------------\n");
2383 fprintf (file, fmt_str, "", " Number of ", "Memory");
2384 fprintf (file, fmt_str, "", " instances ", "used ");
2385 fprintf (file, "---------------------------------------------------------\n");
2387 size = n_basic_blocks * sizeof (struct basic_block_def);
2389 fprintf (file, fmt_str_1, "Basic blocks", n_basic_blocks,
2390 SCALE (size), LABEL (size));
2394 num_edges += EDGE_COUNT (bb->succs);
2395 size = num_edges * sizeof (struct edge_def);
2397 fprintf (file, fmt_str_2, "Edges", num_edges, SCALE (size), LABEL (size));
2399 fprintf (file, "---------------------------------------------------------\n");
2400 fprintf (file, fmt_str_3, "Total memory used by CFG data", SCALE (total),
2402 fprintf (file, "---------------------------------------------------------\n");
2403 fprintf (file, "\n");
2405 if (cfg_stats.num_merged_labels > max_num_merged_labels)
2406 max_num_merged_labels = cfg_stats.num_merged_labels;
2408 fprintf (file, "Coalesced label blocks: %ld (Max so far: %ld)\n",
2409 cfg_stats.num_merged_labels, max_num_merged_labels);
2411 fprintf (file, "\n");
2415 /* Dump CFG statistics on stderr. Keep extern so that it's always
2416 linked in the final executable. */
2419 debug_cfg_stats (void)
2421 dump_cfg_stats (stderr);
2425 /* Dump the flowgraph to a .vcg FILE. */
2428 gimple_cfg2vcg (FILE *file)
2433 const char *funcname
2434 = lang_hooks.decl_printable_name (current_function_decl, 2);
2436 /* Write the file header. */
2437 fprintf (file, "graph: { title: \"%s\"\n", funcname);
2438 fprintf (file, "node: { title: \"ENTRY\" label: \"ENTRY\" }\n");
2439 fprintf (file, "node: { title: \"EXIT\" label: \"EXIT\" }\n");
2441 /* Write blocks and edges. */
2442 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
2444 fprintf (file, "edge: { sourcename: \"ENTRY\" targetname: \"%d\"",
2447 if (e->flags & EDGE_FAKE)
2448 fprintf (file, " linestyle: dotted priority: 10");
2450 fprintf (file, " linestyle: solid priority: 100");
2452 fprintf (file, " }\n");
2458 enum gimple_code head_code, end_code;
2459 const char *head_name, *end_name;
2462 gimple first = first_stmt (bb);
2463 gimple last = last_stmt (bb);
2467 head_code = gimple_code (first);
2468 head_name = gimple_code_name[head_code];
2469 head_line = get_lineno (first);
2472 head_name = "no-statement";
2476 end_code = gimple_code (last);
2477 end_name = gimple_code_name[end_code];
2478 end_line = get_lineno (last);
2481 end_name = "no-statement";
2483 fprintf (file, "node: { title: \"%d\" label: \"#%d\\n%s (%d)\\n%s (%d)\"}\n",
2484 bb->index, bb->index, head_name, head_line, end_name,
2487 FOR_EACH_EDGE (e, ei, bb->succs)
2489 if (e->dest == EXIT_BLOCK_PTR)
2490 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"EXIT\"", bb->index);
2492 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"%d\"", bb->index, e->dest->index);
2494 if (e->flags & EDGE_FAKE)
2495 fprintf (file, " priority: 10 linestyle: dotted");
2497 fprintf (file, " priority: 100 linestyle: solid");
2499 fprintf (file, " }\n");
2502 if (bb->next_bb != EXIT_BLOCK_PTR)
2506 fputs ("}\n\n", file);
2511 /*---------------------------------------------------------------------------
2512 Miscellaneous helpers
2513 ---------------------------------------------------------------------------*/
2515 /* Return true if T represents a stmt that always transfers control. */
2518 is_ctrl_stmt (gimple t)
2520 return gimple_code (t) == GIMPLE_COND
2521 || gimple_code (t) == GIMPLE_SWITCH
2522 || gimple_code (t) == GIMPLE_GOTO
2523 || gimple_code (t) == GIMPLE_RETURN
2524 || gimple_code (t) == GIMPLE_RESX;
2528 /* Return true if T is a statement that may alter the flow of control
2529 (e.g., a call to a non-returning function). */
2532 is_ctrl_altering_stmt (gimple t)
2536 if (is_gimple_call (t))
2538 int flags = gimple_call_flags (t);
2540 /* A non-pure/const call alters flow control if the current
2541 function has nonlocal labels. */
2542 if (!(flags & (ECF_CONST | ECF_PURE))
2543 && cfun->has_nonlocal_label)
2546 /* A call also alters control flow if it does not return. */
2547 if (gimple_call_flags (t) & ECF_NORETURN)
2551 /* OpenMP directives alter control flow. */
2552 if (is_gimple_omp (t))
2555 /* If a statement can throw, it alters control flow. */
2556 return stmt_can_throw_internal (t);
2560 /* Return true if T is a simple local goto. */
2563 simple_goto_p (gimple t)
2565 return (gimple_code (t) == GIMPLE_GOTO
2566 && TREE_CODE (gimple_goto_dest (t)) == LABEL_DECL);
2570 /* Return true if T can make an abnormal transfer of control flow.
2571 Transfers of control flow associated with EH are excluded. */
2574 stmt_can_make_abnormal_goto (gimple t)
2576 if (computed_goto_p (t))
2578 if (is_gimple_call (t))
2579 return gimple_has_side_effects (t) && cfun->has_nonlocal_label;
2584 /* Return true if STMT should start a new basic block. PREV_STMT is
2585 the statement preceding STMT. It is used when STMT is a label or a
2586 case label. Labels should only start a new basic block if their
2587 previous statement wasn't a label. Otherwise, sequence of labels
2588 would generate unnecessary basic blocks that only contain a single
2592 stmt_starts_bb_p (gimple stmt, gimple prev_stmt)
2597 /* Labels start a new basic block only if the preceding statement
2598 wasn't a label of the same type. This prevents the creation of
2599 consecutive blocks that have nothing but a single label. */
2600 if (gimple_code (stmt) == GIMPLE_LABEL)
2602 /* Nonlocal and computed GOTO targets always start a new block. */
2603 if (DECL_NONLOCAL (gimple_label_label (stmt))
2604 || FORCED_LABEL (gimple_label_label (stmt)))
2607 if (prev_stmt && gimple_code (prev_stmt) == GIMPLE_LABEL)
2609 if (DECL_NONLOCAL (gimple_label_label (prev_stmt)))
2612 cfg_stats.num_merged_labels++;
2623 /* Return true if T should end a basic block. */
2626 stmt_ends_bb_p (gimple t)
2628 return is_ctrl_stmt (t) || is_ctrl_altering_stmt (t);
2631 /* Remove block annotations and other data structures. */
2634 delete_tree_cfg_annotations (void)
2636 label_to_block_map = NULL;
2640 /* Return the first statement in basic block BB. */
2643 first_stmt (basic_block bb)
2645 gimple_stmt_iterator i = gsi_start_bb (bb);
2646 return !gsi_end_p (i) ? gsi_stmt (i) : NULL;
2649 /* Return the last statement in basic block BB. */
2652 last_stmt (basic_block bb)
2654 gimple_stmt_iterator b = gsi_last_bb (bb);
2655 return !gsi_end_p (b) ? gsi_stmt (b) : NULL;
2658 /* Return the last statement of an otherwise empty block. Return NULL
2659 if the block is totally empty, or if it contains more than one
2663 last_and_only_stmt (basic_block bb)
2665 gimple_stmt_iterator i = gsi_last_bb (bb);
2671 last = gsi_stmt (i);
2676 /* Empty statements should no longer appear in the instruction stream.
2677 Everything that might have appeared before should be deleted by
2678 remove_useless_stmts, and the optimizers should just gsi_remove
2679 instead of smashing with build_empty_stmt.
2681 Thus the only thing that should appear here in a block containing
2682 one executable statement is a label. */
2683 prev = gsi_stmt (i);
2684 if (gimple_code (prev) == GIMPLE_LABEL)
2690 /* Reinstall those PHI arguments queued in OLD_EDGE to NEW_EDGE. */
2693 reinstall_phi_args (edge new_edge, edge old_edge)
2695 edge_var_map_vector v;
2698 gimple_stmt_iterator phis;
2700 v = redirect_edge_var_map_vector (old_edge);
2704 for (i = 0, phis = gsi_start_phis (new_edge->dest);
2705 VEC_iterate (edge_var_map, v, i, vm) && !gsi_end_p (phis);
2706 i++, gsi_next (&phis))
2708 gimple phi = gsi_stmt (phis);
2709 tree result = redirect_edge_var_map_result (vm);
2710 tree arg = redirect_edge_var_map_def (vm);
2712 gcc_assert (result == gimple_phi_result (phi));
2714 add_phi_arg (phi, arg, new_edge);
2717 redirect_edge_var_map_clear (old_edge);
2720 /* Returns the basic block after which the new basic block created
2721 by splitting edge EDGE_IN should be placed. Tries to keep the new block
2722 near its "logical" location. This is of most help to humans looking
2723 at debugging dumps. */
2726 split_edge_bb_loc (edge edge_in)
2728 basic_block dest = edge_in->dest;
2730 if (dest->prev_bb && find_edge (dest->prev_bb, dest))
2731 return edge_in->src;
2733 return dest->prev_bb;
2736 /* Split a (typically critical) edge EDGE_IN. Return the new block.
2737 Abort on abnormal edges. */
2740 gimple_split_edge (edge edge_in)
2742 basic_block new_bb, after_bb, dest;
2745 /* Abnormal edges cannot be split. */
2746 gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
2748 dest = edge_in->dest;
2750 after_bb = split_edge_bb_loc (edge_in);
2752 new_bb = create_empty_bb (after_bb);
2753 new_bb->frequency = EDGE_FREQUENCY (edge_in);
2754 new_bb->count = edge_in->count;
2755 new_edge = make_edge (new_bb, dest, EDGE_FALLTHRU);
2756 new_edge->probability = REG_BR_PROB_BASE;
2757 new_edge->count = edge_in->count;
2759 e = redirect_edge_and_branch (edge_in, new_bb);
2760 gcc_assert (e == edge_in);
2761 reinstall_phi_args (new_edge, e);
2766 /* Callback for walk_tree, check that all elements with address taken are
2767 properly noticed as such. The DATA is an int* that is 1 if TP was seen
2768 inside a PHI node. */
2771 verify_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
2778 /* Check operand N for being valid GIMPLE and give error MSG if not. */
2779 #define CHECK_OP(N, MSG) \
2780 do { if (!is_gimple_val (TREE_OPERAND (t, N))) \
2781 { error (MSG); return TREE_OPERAND (t, N); }} while (0)
2783 switch (TREE_CODE (t))
2786 if (SSA_NAME_IN_FREE_LIST (t))
2788 error ("SSA name in freelist but still referenced");
2794 x = fold (ASSERT_EXPR_COND (t));
2795 if (x == boolean_false_node)
2797 error ("ASSERT_EXPR with an always-false condition");
2803 x = TREE_OPERAND (t, 0);
2804 if (TREE_CODE (x) == BIT_FIELD_REF
2805 && is_gimple_reg (TREE_OPERAND (x, 0)))
2807 error ("GIMPLE register modified with BIT_FIELD_REF");
2815 bool old_side_effects;
2817 bool new_side_effects;
2819 gcc_assert (is_gimple_address (t));
2821 old_constant = TREE_CONSTANT (t);
2822 old_side_effects = TREE_SIDE_EFFECTS (t);
2824 recompute_tree_invariant_for_addr_expr (t);
2825 new_side_effects = TREE_SIDE_EFFECTS (t);
2826 new_constant = TREE_CONSTANT (t);
2828 if (old_constant != new_constant)
2830 error ("constant not recomputed when ADDR_EXPR changed");
2833 if (old_side_effects != new_side_effects)
2835 error ("side effects not recomputed when ADDR_EXPR changed");
2839 /* Skip any references (they will be checked when we recurse down the
2840 tree) and ensure that any variable used as a prefix is marked
2842 for (x = TREE_OPERAND (t, 0);
2843 handled_component_p (x);
2844 x = TREE_OPERAND (x, 0))
2847 if (TREE_CODE (x) != VAR_DECL && TREE_CODE (x) != PARM_DECL)
2849 if (!TREE_ADDRESSABLE (x))
2851 error ("address taken, but ADDRESSABLE bit not set");
2859 x = COND_EXPR_COND (t);
2860 if (!INTEGRAL_TYPE_P (TREE_TYPE (x)))
2862 error ("non-integral used in condition");
2865 if (!is_gimple_condexpr (x))
2867 error ("invalid conditional operand");
2872 case NON_LVALUE_EXPR:
2876 case FIX_TRUNC_EXPR:
2881 case TRUTH_NOT_EXPR:
2882 CHECK_OP (0, "invalid operand to unary operator");
2889 case ARRAY_RANGE_REF:
2891 case VIEW_CONVERT_EXPR:
2892 /* We have a nest of references. Verify that each of the operands
2893 that determine where to reference is either a constant or a variable,
2894 verify that the base is valid, and then show we've already checked
2896 while (handled_component_p (t))
2898 if (TREE_CODE (t) == COMPONENT_REF && TREE_OPERAND (t, 2))
2899 CHECK_OP (2, "invalid COMPONENT_REF offset operator");
2900 else if (TREE_CODE (t) == ARRAY_REF
2901 || TREE_CODE (t) == ARRAY_RANGE_REF)
2903 CHECK_OP (1, "invalid array index");
2904 if (TREE_OPERAND (t, 2))
2905 CHECK_OP (2, "invalid array lower bound");
2906 if (TREE_OPERAND (t, 3))
2907 CHECK_OP (3, "invalid array stride");
2909 else if (TREE_CODE (t) == BIT_FIELD_REF)
2911 if (!host_integerp (TREE_OPERAND (t, 1), 1)
2912 || !host_integerp (TREE_OPERAND (t, 2), 1))
2914 error ("invalid position or size operand to BIT_FIELD_REF");
2917 else if (INTEGRAL_TYPE_P (TREE_TYPE (t))
2918 && (TYPE_PRECISION (TREE_TYPE (t))
2919 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
2921 error ("integral result type precision does not match "
2922 "field size of BIT_FIELD_REF");
2925 if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
2926 && (GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (t)))
2927 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
2929 error ("mode precision of non-integral result does not "
2930 "match field size of BIT_FIELD_REF");
2935 t = TREE_OPERAND (t, 0);
2938 if (!is_gimple_min_invariant (t) && !is_gimple_lvalue (t))
2940 error ("invalid reference prefix");
2947 /* PLUS_EXPR and MINUS_EXPR don't work on pointers, they should be done using
2948 POINTER_PLUS_EXPR. */
2949 if (POINTER_TYPE_P (TREE_TYPE (t)))
2951 error ("invalid operand to plus/minus, type is a pointer");
2954 CHECK_OP (0, "invalid operand to binary operator");
2955 CHECK_OP (1, "invalid operand to binary operator");
2958 case POINTER_PLUS_EXPR:
2959 /* Check to make sure the first operand is a pointer or reference type. */
2960 if (!POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 0))))
2962 error ("invalid operand to pointer plus, first operand is not a pointer");
2965 /* Check to make sure the second operand is an integer with type of
2967 if (!useless_type_conversion_p (sizetype,
2968 TREE_TYPE (TREE_OPERAND (t, 1))))
2970 error ("invalid operand to pointer plus, second operand is not an "
2971 "integer with type of sizetype.");
2981 case UNORDERED_EXPR:
2990 case TRUNC_DIV_EXPR:
2992 case FLOOR_DIV_EXPR:
2993 case ROUND_DIV_EXPR:
2994 case TRUNC_MOD_EXPR:
2996 case FLOOR_MOD_EXPR:
2997 case ROUND_MOD_EXPR:
2999 case EXACT_DIV_EXPR:
3009 CHECK_OP (0, "invalid operand to binary operator");
3010 CHECK_OP (1, "invalid operand to binary operator");
3014 if (TREE_CONSTANT (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
3027 /* Verify if EXPR is either a GIMPLE ID or a GIMPLE indirect reference.
3028 Returns true if there is an error, otherwise false. */
3031 verify_types_in_gimple_min_lval (tree expr)
3035 if (is_gimple_id (expr))
3038 if (!INDIRECT_REF_P (expr)
3039 && TREE_CODE (expr) != TARGET_MEM_REF)
3041 error ("invalid expression for min lvalue");
3045 /* TARGET_MEM_REFs are strange beasts. */
3046 if (TREE_CODE (expr) == TARGET_MEM_REF)
3049 op = TREE_OPERAND (expr, 0);
3050 if (!is_gimple_val (op))
3052 error ("invalid operand in indirect reference");
3053 debug_generic_stmt (op);
3056 if (!useless_type_conversion_p (TREE_TYPE (expr),
3057 TREE_TYPE (TREE_TYPE (op))))
3059 error ("type mismatch in indirect reference");
3060 debug_generic_stmt (TREE_TYPE (expr));
3061 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3068 /* Verify if EXPR is a valid GIMPLE reference expression. Returns true
3069 if there is an error, otherwise false. */
3072 verify_types_in_gimple_reference (tree expr)
3074 while (handled_component_p (expr))
3076 tree op = TREE_OPERAND (expr, 0);
3078 if (TREE_CODE (expr) == ARRAY_REF
3079 || TREE_CODE (expr) == ARRAY_RANGE_REF)
3081 if (!is_gimple_val (TREE_OPERAND (expr, 1))
3082 || (TREE_OPERAND (expr, 2)
3083 && !is_gimple_val (TREE_OPERAND (expr, 2)))
3084 || (TREE_OPERAND (expr, 3)
3085 && !is_gimple_val (TREE_OPERAND (expr, 3))))
3087 error ("invalid operands to array reference");
3088 debug_generic_stmt (expr);
3093 /* Verify if the reference array element types are compatible. */
3094 if (TREE_CODE (expr) == ARRAY_REF
3095 && !useless_type_conversion_p (TREE_TYPE (expr),
3096 TREE_TYPE (TREE_TYPE (op))))
3098 error ("type mismatch in array reference");
3099 debug_generic_stmt (TREE_TYPE (expr));
3100 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3103 if (TREE_CODE (expr) == ARRAY_RANGE_REF
3104 && !useless_type_conversion_p (TREE_TYPE (TREE_TYPE (expr)),
3105 TREE_TYPE (TREE_TYPE (op))))
3107 error ("type mismatch in array range reference");
3108 debug_generic_stmt (TREE_TYPE (TREE_TYPE (expr)));
3109 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3113 if ((TREE_CODE (expr) == REALPART_EXPR
3114 || TREE_CODE (expr) == IMAGPART_EXPR)
3115 && !useless_type_conversion_p (TREE_TYPE (expr),
3116 TREE_TYPE (TREE_TYPE (op))))
3118 error ("type mismatch in real/imagpart reference");
3119 debug_generic_stmt (TREE_TYPE (expr));
3120 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3124 if (TREE_CODE (expr) == COMPONENT_REF
3125 && !useless_type_conversion_p (TREE_TYPE (expr),
3126 TREE_TYPE (TREE_OPERAND (expr, 1))))
3128 error ("type mismatch in component reference");
3129 debug_generic_stmt (TREE_TYPE (expr));
3130 debug_generic_stmt (TREE_TYPE (TREE_OPERAND (expr, 1)));
3134 /* For VIEW_CONVERT_EXPRs which are allowed here, too, there
3135 is nothing to verify. Gross mismatches at most invoke
3136 undefined behavior. */
3137 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR
3138 && !handled_component_p (op))
3144 return verify_types_in_gimple_min_lval (expr);
3147 /* Returns true if there is one pointer type in TYPE_POINTER_TO (SRC_OBJ)
3148 list of pointer-to types that is trivially convertible to DEST. */
3151 one_pointer_to_useless_type_conversion_p (tree dest, tree src_obj)
3155 if (!TYPE_POINTER_TO (src_obj))
3158 for (src = TYPE_POINTER_TO (src_obj); src; src = TYPE_NEXT_PTR_TO (src))
3159 if (useless_type_conversion_p (dest, src))
3165 /* Return true if TYPE1 is a fixed-point type and if conversions to and
3166 from TYPE2 can be handled by FIXED_CONVERT_EXPR. */
3169 valid_fixed_convert_types_p (tree type1, tree type2)
3171 return (FIXED_POINT_TYPE_P (type1)
3172 && (INTEGRAL_TYPE_P (type2)
3173 || SCALAR_FLOAT_TYPE_P (type2)
3174 || FIXED_POINT_TYPE_P (type2)));
3177 /* Verify the contents of a GIMPLE_CALL STMT. Returns true when there
3178 is a problem, otherwise false. */
3181 verify_gimple_call (gimple stmt)
3183 tree fn = gimple_call_fn (stmt);
3186 if (!POINTER_TYPE_P (TREE_TYPE (fn))
3187 || (TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != FUNCTION_TYPE
3188 && TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != METHOD_TYPE))
3190 error ("non-function in gimple call");
3194 if (gimple_call_lhs (stmt)
3195 && !is_gimple_lvalue (gimple_call_lhs (stmt)))
3197 error ("invalid LHS in gimple call");
3201 fntype = TREE_TYPE (TREE_TYPE (fn));
3202 if (gimple_call_lhs (stmt)
3203 && !useless_type_conversion_p (TREE_TYPE (gimple_call_lhs (stmt)),
3205 /* ??? At least C++ misses conversions at assignments from
3206 void * call results.
3207 ??? Java is completely off. Especially with functions
3208 returning java.lang.Object.
3209 For now simply allow arbitrary pointer type conversions. */
3210 && !(POINTER_TYPE_P (TREE_TYPE (gimple_call_lhs (stmt)))
3211 && POINTER_TYPE_P (TREE_TYPE (fntype))))
3213 error ("invalid conversion in gimple call");
3214 debug_generic_stmt (TREE_TYPE (gimple_call_lhs (stmt)));
3215 debug_generic_stmt (TREE_TYPE (fntype));
3219 /* ??? The C frontend passes unpromoted arguments in case it
3220 didn't see a function declaration before the call. So for now
3221 leave the call arguments unverified. Once we gimplify
3222 unit-at-a-time we have a chance to fix this. */
3227 /* Verifies the gimple comparison with the result type TYPE and
3228 the operands OP0 and OP1. */
3231 verify_gimple_comparison (tree type, tree op0, tree op1)
3233 tree op0_type = TREE_TYPE (op0);
3234 tree op1_type = TREE_TYPE (op1);
3236 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3238 error ("invalid operands in gimple comparison");
3242 /* For comparisons we do not have the operations type as the
3243 effective type the comparison is carried out in. Instead
3244 we require that either the first operand is trivially
3245 convertible into the second, or the other way around.
3246 The resulting type of a comparison may be any integral type.
3247 Because we special-case pointers to void we allow
3248 comparisons of pointers with the same mode as well. */
3249 if ((!useless_type_conversion_p (op0_type, op1_type)
3250 && !useless_type_conversion_p (op1_type, op0_type)
3251 && (!POINTER_TYPE_P (op0_type)
3252 || !POINTER_TYPE_P (op1_type)
3253 || TYPE_MODE (op0_type) != TYPE_MODE (op1_type)))
3254 || !INTEGRAL_TYPE_P (type))
3256 error ("type mismatch in comparison expression");
3257 debug_generic_expr (type);
3258 debug_generic_expr (op0_type);
3259 debug_generic_expr (op1_type);
3266 /* Verify a gimple assignment statement STMT with an unary rhs.
3267 Returns true if anything is wrong. */
3270 verify_gimple_assign_unary (gimple stmt)
3272 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3273 tree lhs = gimple_assign_lhs (stmt);
3274 tree lhs_type = TREE_TYPE (lhs);
3275 tree rhs1 = gimple_assign_rhs1 (stmt);
3276 tree rhs1_type = TREE_TYPE (rhs1);
3278 if (!is_gimple_reg (lhs)
3280 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3282 error ("non-register as LHS of unary operation");
3286 if (!is_gimple_val (rhs1))
3288 error ("invalid operand in unary operation");
3292 /* First handle conversions. */
3297 /* Allow conversions between integral types and pointers only if
3298 there is no sign or zero extension involved.
3299 For targets were the precision of sizetype doesn't match that
3300 of pointers we need to allow arbitrary conversions from and
3302 if ((POINTER_TYPE_P (lhs_type)
3303 && INTEGRAL_TYPE_P (rhs1_type)
3304 && (TYPE_PRECISION (lhs_type) >= TYPE_PRECISION (rhs1_type)
3305 || rhs1_type == sizetype))
3306 || (POINTER_TYPE_P (rhs1_type)
3307 && INTEGRAL_TYPE_P (lhs_type)
3308 && (TYPE_PRECISION (rhs1_type) >= TYPE_PRECISION (lhs_type)
3309 || lhs_type == sizetype)))
3312 /* Allow conversion from integer to offset type and vice versa. */
3313 if ((TREE_CODE (lhs_type) == OFFSET_TYPE
3314 && TREE_CODE (rhs1_type) == INTEGER_TYPE)
3315 || (TREE_CODE (lhs_type) == INTEGER_TYPE
3316 && TREE_CODE (rhs1_type) == OFFSET_TYPE))
3319 /* Otherwise assert we are converting between types of the
3321 if (INTEGRAL_TYPE_P (lhs_type) != INTEGRAL_TYPE_P (rhs1_type))
3323 error ("invalid types in nop conversion");
3324 debug_generic_expr (lhs_type);
3325 debug_generic_expr (rhs1_type);
3332 case FIXED_CONVERT_EXPR:
3334 if (!valid_fixed_convert_types_p (lhs_type, rhs1_type)
3335 && !valid_fixed_convert_types_p (rhs1_type, lhs_type))
3337 error ("invalid types in fixed-point conversion");
3338 debug_generic_expr (lhs_type);
3339 debug_generic_expr (rhs1_type);
3348 if (!INTEGRAL_TYPE_P (rhs1_type) || !SCALAR_FLOAT_TYPE_P (lhs_type))
3350 error ("invalid types in conversion to floating point");
3351 debug_generic_expr (lhs_type);
3352 debug_generic_expr (rhs1_type);
3359 case FIX_TRUNC_EXPR:
3361 if (!INTEGRAL_TYPE_P (lhs_type) || !SCALAR_FLOAT_TYPE_P (rhs1_type))
3363 error ("invalid types in conversion to integer");
3364 debug_generic_expr (lhs_type);
3365 debug_generic_expr (rhs1_type);
3372 case TRUTH_NOT_EXPR:
3380 case NON_LVALUE_EXPR:
3382 case REDUC_MAX_EXPR:
3383 case REDUC_MIN_EXPR:
3384 case REDUC_PLUS_EXPR:
3385 case VEC_UNPACK_HI_EXPR:
3386 case VEC_UNPACK_LO_EXPR:
3387 case VEC_UNPACK_FLOAT_HI_EXPR:
3388 case VEC_UNPACK_FLOAT_LO_EXPR:
3395 /* For the remaining codes assert there is no conversion involved. */
3396 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3398 error ("non-trivial conversion in unary operation");
3399 debug_generic_expr (lhs_type);
3400 debug_generic_expr (rhs1_type);
3407 /* Verify a gimple assignment statement STMT with a binary rhs.
3408 Returns true if anything is wrong. */
3411 verify_gimple_assign_binary (gimple stmt)
3413 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3414 tree lhs = gimple_assign_lhs (stmt);
3415 tree lhs_type = TREE_TYPE (lhs);
3416 tree rhs1 = gimple_assign_rhs1 (stmt);
3417 tree rhs1_type = TREE_TYPE (rhs1);
3418 tree rhs2 = gimple_assign_rhs2 (stmt);
3419 tree rhs2_type = TREE_TYPE (rhs2);
3421 if (!is_gimple_reg (lhs)
3423 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3425 error ("non-register as LHS of binary operation");
3429 if (!is_gimple_val (rhs1)
3430 || !is_gimple_val (rhs2))
3432 error ("invalid operands in binary operation");
3436 /* First handle operations that involve different types. */
3441 if (TREE_CODE (lhs_type) != COMPLEX_TYPE
3442 || !(INTEGRAL_TYPE_P (rhs1_type)
3443 || SCALAR_FLOAT_TYPE_P (rhs1_type))
3444 || !(INTEGRAL_TYPE_P (rhs2_type)
3445 || SCALAR_FLOAT_TYPE_P (rhs2_type)))
3447 error ("type mismatch in complex expression");
3448 debug_generic_expr (lhs_type);
3449 debug_generic_expr (rhs1_type);
3450 debug_generic_expr (rhs2_type);
3462 if (!INTEGRAL_TYPE_P (rhs1_type)
3463 || !INTEGRAL_TYPE_P (rhs2_type)
3464 || !useless_type_conversion_p (lhs_type, rhs1_type))
3466 error ("type mismatch in shift expression");
3467 debug_generic_expr (lhs_type);
3468 debug_generic_expr (rhs1_type);
3469 debug_generic_expr (rhs2_type);
3476 case VEC_LSHIFT_EXPR:
3477 case VEC_RSHIFT_EXPR:
3479 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3480 || !INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))
3481 || (!INTEGRAL_TYPE_P (rhs2_type)
3482 && (TREE_CODE (rhs2_type) != VECTOR_TYPE
3483 || !INTEGRAL_TYPE_P (TREE_TYPE (rhs2_type))))
3484 || !useless_type_conversion_p (lhs_type, rhs1_type))
3486 error ("type mismatch in vector shift expression");
3487 debug_generic_expr (lhs_type);
3488 debug_generic_expr (rhs1_type);
3489 debug_generic_expr (rhs2_type);
3496 case POINTER_PLUS_EXPR:
3498 if (!POINTER_TYPE_P (rhs1_type)
3499 || !useless_type_conversion_p (lhs_type, rhs1_type)
3500 || !useless_type_conversion_p (sizetype, rhs2_type))
3502 error ("type mismatch in pointer plus expression");
3503 debug_generic_stmt (lhs_type);
3504 debug_generic_stmt (rhs1_type);
3505 debug_generic_stmt (rhs2_type);
3512 case TRUTH_ANDIF_EXPR:
3513 case TRUTH_ORIF_EXPR:
3516 case TRUTH_AND_EXPR:
3518 case TRUTH_XOR_EXPR:
3520 /* We allow any kind of integral typed argument and result. */
3521 if (!INTEGRAL_TYPE_P (rhs1_type)
3522 || !INTEGRAL_TYPE_P (rhs2_type)
3523 || !INTEGRAL_TYPE_P (lhs_type))
3525 error ("type mismatch in binary truth expression");
3526 debug_generic_expr (lhs_type);
3527 debug_generic_expr (rhs1_type);
3528 debug_generic_expr (rhs2_type);
3541 case UNORDERED_EXPR:
3549 /* Comparisons are also binary, but the result type is not
3550 connected to the operand types. */
3551 return verify_gimple_comparison (lhs_type, rhs1, rhs2);
3556 if (POINTER_TYPE_P (lhs_type)
3557 || POINTER_TYPE_P (rhs1_type)
3558 || POINTER_TYPE_P (rhs2_type))
3560 error ("invalid (pointer) operands to plus/minus");
3564 /* Continue with generic binary expression handling. */
3569 case TRUNC_DIV_EXPR:
3571 case FLOOR_DIV_EXPR:
3572 case ROUND_DIV_EXPR:
3573 case TRUNC_MOD_EXPR:
3575 case FLOOR_MOD_EXPR:
3576 case ROUND_MOD_EXPR:
3578 case EXACT_DIV_EXPR:
3584 case WIDEN_SUM_EXPR:
3585 case WIDEN_MULT_EXPR:
3586 case VEC_WIDEN_MULT_HI_EXPR:
3587 case VEC_WIDEN_MULT_LO_EXPR:
3588 case VEC_PACK_TRUNC_EXPR:
3589 case VEC_PACK_SAT_EXPR:
3590 case VEC_PACK_FIX_TRUNC_EXPR:
3591 case VEC_EXTRACT_EVEN_EXPR:
3592 case VEC_EXTRACT_ODD_EXPR:
3593 case VEC_INTERLEAVE_HIGH_EXPR:
3594 case VEC_INTERLEAVE_LOW_EXPR:
3595 /* Continue with generic binary expression handling. */
3602 if (!useless_type_conversion_p (lhs_type, rhs1_type)
3603 || !useless_type_conversion_p (lhs_type, rhs2_type))
3605 error ("type mismatch in binary expression");
3606 debug_generic_stmt (lhs_type);
3607 debug_generic_stmt (rhs1_type);
3608 debug_generic_stmt (rhs2_type);
3615 /* Verify a gimple assignment statement STMT with a single rhs.
3616 Returns true if anything is wrong. */
3619 verify_gimple_assign_single (gimple stmt)
3621 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3622 tree lhs = gimple_assign_lhs (stmt);
3623 tree lhs_type = TREE_TYPE (lhs);
3624 tree rhs1 = gimple_assign_rhs1 (stmt);
3625 tree rhs1_type = TREE_TYPE (rhs1);
3628 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3630 error ("non-trivial conversion at assignment");
3631 debug_generic_expr (lhs_type);
3632 debug_generic_expr (rhs1_type);
3636 if (handled_component_p (lhs))
3637 res |= verify_types_in_gimple_reference (lhs);
3639 /* Special codes we cannot handle via their class. */
3644 tree op = TREE_OPERAND (rhs1, 0);
3645 if (!is_gimple_addressable (op))
3647 error ("invalid operand in unary expression");
3651 if (!one_pointer_to_useless_type_conversion_p (lhs_type, TREE_TYPE (op))
3652 /* FIXME: a longstanding wart, &a == &a[0]. */
3653 && (TREE_CODE (TREE_TYPE (op)) != ARRAY_TYPE
3654 || !one_pointer_to_useless_type_conversion_p (lhs_type,
3655 TREE_TYPE (TREE_TYPE (op)))))
3657 error ("type mismatch in address expression");
3658 debug_generic_stmt (lhs_type);
3659 debug_generic_stmt (TYPE_POINTER_TO (TREE_TYPE (op)));
3663 return verify_types_in_gimple_reference (op);
3670 case ALIGN_INDIRECT_REF:
3671 case MISALIGNED_INDIRECT_REF:
3673 case ARRAY_RANGE_REF:
3674 case VIEW_CONVERT_EXPR:
3677 case TARGET_MEM_REF:
3678 if (!is_gimple_reg (lhs)
3679 && is_gimple_reg_type (TREE_TYPE (lhs)))
3681 error ("invalid rhs for gimple memory store");
3682 debug_generic_stmt (lhs);
3683 debug_generic_stmt (rhs1);
3686 return res || verify_types_in_gimple_reference (rhs1);
3698 /* tcc_declaration */
3703 if (!is_gimple_reg (lhs)
3704 && !is_gimple_reg (rhs1)
3705 && is_gimple_reg_type (TREE_TYPE (lhs)))
3707 error ("invalid rhs for gimple memory store");
3708 debug_generic_stmt (lhs);
3709 debug_generic_stmt (rhs1);
3718 case WITH_SIZE_EXPR:
3721 case POLYNOMIAL_CHREC:
3724 case REALIGN_LOAD_EXPR:
3734 /* Verify the contents of a GIMPLE_ASSIGN STMT. Returns true when there
3735 is a problem, otherwise false. */
3738 verify_gimple_assign (gimple stmt)
3740 switch (gimple_assign_rhs_class (stmt))
3742 case GIMPLE_SINGLE_RHS:
3743 return verify_gimple_assign_single (stmt);
3745 case GIMPLE_UNARY_RHS:
3746 return verify_gimple_assign_unary (stmt);
3748 case GIMPLE_BINARY_RHS:
3749 return verify_gimple_assign_binary (stmt);
3756 /* Verify the contents of a GIMPLE_RETURN STMT. Returns true when there
3757 is a problem, otherwise false. */
3760 verify_gimple_return (gimple stmt)
3762 tree op = gimple_return_retval (stmt);
3763 tree restype = TREE_TYPE (TREE_TYPE (cfun->decl));
3765 /* We cannot test for present return values as we do not fix up missing
3766 return values from the original source. */
3770 if (!is_gimple_val (op)
3771 && TREE_CODE (op) != RESULT_DECL)
3773 error ("invalid operand in return statement");
3774 debug_generic_stmt (op);
3778 if (!useless_type_conversion_p (restype, TREE_TYPE (op))
3779 /* ??? With C++ we can have the situation that the result
3780 decl is a reference type while the return type is an aggregate. */
3781 && !(TREE_CODE (op) == RESULT_DECL
3782 && TREE_CODE (TREE_TYPE (op)) == REFERENCE_TYPE
3783 && useless_type_conversion_p (restype, TREE_TYPE (TREE_TYPE (op)))))
3785 error ("invalid conversion in return statement");
3786 debug_generic_stmt (restype);
3787 debug_generic_stmt (TREE_TYPE (op));
3795 /* Verify the contents of a GIMPLE_GOTO STMT. Returns true when there
3796 is a problem, otherwise false. */
3799 verify_gimple_goto (gimple stmt)
3801 tree dest = gimple_goto_dest (stmt);
3803 /* ??? We have two canonical forms of direct goto destinations, a
3804 bare LABEL_DECL and an ADDR_EXPR of a LABEL_DECL. */
3805 if (TREE_CODE (dest) != LABEL_DECL
3806 && (!is_gimple_val (dest)
3807 || !POINTER_TYPE_P (TREE_TYPE (dest))))
3809 error ("goto destination is neither a label nor a pointer");
3816 /* Verify the contents of a GIMPLE_SWITCH STMT. Returns true when there
3817 is a problem, otherwise false. */
3820 verify_gimple_switch (gimple stmt)
3822 if (!is_gimple_val (gimple_switch_index (stmt)))
3824 error ("invalid operand to switch statement");
3825 debug_generic_stmt (gimple_switch_index (stmt));
3833 /* Verify the contents of a GIMPLE_PHI. Returns true if there is a problem,
3834 and false otherwise. */
3837 verify_gimple_phi (gimple stmt)
3839 tree type = TREE_TYPE (gimple_phi_result (stmt));
3842 if (!is_gimple_variable (gimple_phi_result (stmt)))
3844 error ("Invalid PHI result");
3848 for (i = 0; i < gimple_phi_num_args (stmt); i++)
3850 tree arg = gimple_phi_arg_def (stmt, i);
3851 if ((is_gimple_reg (gimple_phi_result (stmt))
3852 && !is_gimple_val (arg))
3853 || (!is_gimple_reg (gimple_phi_result (stmt))
3854 && !is_gimple_addressable (arg)))
3856 error ("Invalid PHI argument");
3857 debug_generic_stmt (arg);
3860 if (!useless_type_conversion_p (type, TREE_TYPE (arg)))
3862 error ("Incompatible types in PHI argument");
3863 debug_generic_stmt (type);
3864 debug_generic_stmt (TREE_TYPE (arg));
3873 /* Verify the GIMPLE statement STMT. Returns true if there is an
3874 error, otherwise false. */
3877 verify_types_in_gimple_stmt (gimple stmt)
3879 if (is_gimple_omp (stmt))
3881 /* OpenMP directives are validated by the FE and never operated
3882 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
3883 non-gimple expressions when the main index variable has had
3884 its address taken. This does not affect the loop itself
3885 because the header of an GIMPLE_OMP_FOR is merely used to determine
3886 how to setup the parallel iteration. */
3890 switch (gimple_code (stmt))
3893 return verify_gimple_assign (stmt);
3896 return TREE_CODE (gimple_label_label (stmt)) != LABEL_DECL;
3899 return verify_gimple_call (stmt);
3902 return verify_gimple_comparison (boolean_type_node,
3903 gimple_cond_lhs (stmt),
3904 gimple_cond_rhs (stmt));
3907 return verify_gimple_goto (stmt);
3910 return verify_gimple_switch (stmt);
3913 return verify_gimple_return (stmt);
3918 case GIMPLE_CHANGE_DYNAMIC_TYPE:
3919 return (!is_gimple_val (gimple_cdt_location (stmt))
3920 || !POINTER_TYPE_P (TREE_TYPE (gimple_cdt_location (stmt))));
3923 return verify_gimple_phi (stmt);
3925 /* Tuples that do not have tree operands. */
3928 case GIMPLE_PREDICT:
3936 /* Verify the GIMPLE statements inside the sequence STMTS. */
3939 verify_types_in_gimple_seq_2 (gimple_seq stmts)
3941 gimple_stmt_iterator ittr;
3944 for (ittr = gsi_start (stmts); !gsi_end_p (ittr); gsi_next (&ittr))
3946 gimple stmt = gsi_stmt (ittr);
3948 switch (gimple_code (stmt))
3951 err |= verify_types_in_gimple_seq_2 (gimple_bind_body (stmt));
3955 err |= verify_types_in_gimple_seq_2 (gimple_try_eval (stmt));
3956 err |= verify_types_in_gimple_seq_2 (gimple_try_cleanup (stmt));
3959 case GIMPLE_EH_FILTER:
3960 err |= verify_types_in_gimple_seq_2 (gimple_eh_filter_failure (stmt));
3964 err |= verify_types_in_gimple_seq_2 (gimple_catch_handler (stmt));
3969 bool err2 = verify_types_in_gimple_stmt (stmt);
3971 debug_gimple_stmt (stmt);
3981 /* Verify the GIMPLE statements inside the statement list STMTS. */
3984 verify_types_in_gimple_seq (gimple_seq stmts)
3986 if (verify_types_in_gimple_seq_2 (stmts))
3987 internal_error ("verify_gimple failed");
3991 /* Verify STMT, return true if STMT is not in GIMPLE form.
3992 TODO: Implement type checking. */
3995 verify_stmt (gimple_stmt_iterator *gsi)
3998 struct walk_stmt_info wi;
3999 bool last_in_block = gsi_one_before_end_p (*gsi);
4000 gimple stmt = gsi_stmt (*gsi);
4002 if (is_gimple_omp (stmt))
4004 /* OpenMP directives are validated by the FE and never operated
4005 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4006 non-gimple expressions when the main index variable has had
4007 its address taken. This does not affect the loop itself
4008 because the header of an GIMPLE_OMP_FOR is merely used to determine
4009 how to setup the parallel iteration. */
4013 /* FIXME. The C frontend passes unpromoted arguments in case it
4014 didn't see a function declaration before the call. */
4015 if (is_gimple_call (stmt))
4019 if (!is_gimple_call_addr (gimple_call_fn (stmt)))
4021 error ("invalid function in call statement");
4025 decl = gimple_call_fndecl (stmt);
4027 && TREE_CODE (decl) == FUNCTION_DECL
4028 && DECL_LOOPING_CONST_OR_PURE_P (decl)
4029 && (!DECL_PURE_P (decl))
4030 && (!TREE_READONLY (decl)))
4032 error ("invalid pure const state for function");
4037 memset (&wi, 0, sizeof (wi));
4038 addr = walk_gimple_op (gsi_stmt (*gsi), verify_expr, &wi);
4041 debug_generic_expr (addr);
4042 inform (input_location, "in statement");
4043 debug_gimple_stmt (stmt);
4047 /* If the statement is marked as part of an EH region, then it is
4048 expected that the statement could throw. Verify that when we
4049 have optimizations that simplify statements such that we prove
4050 that they cannot throw, that we update other data structures
4052 if (lookup_stmt_eh_region (stmt) >= 0)
4054 if (!stmt_could_throw_p (stmt))
4056 error ("statement marked for throw, but doesn%'t");
4059 if (!last_in_block && stmt_can_throw_internal (stmt))
4061 error ("statement marked for throw in middle of block");
4069 debug_gimple_stmt (stmt);
4074 /* Return true when the T can be shared. */
4077 tree_node_can_be_shared (tree t)
4079 if (IS_TYPE_OR_DECL_P (t)
4080 || is_gimple_min_invariant (t)
4081 || TREE_CODE (t) == SSA_NAME
4082 || t == error_mark_node
4083 || TREE_CODE (t) == IDENTIFIER_NODE)
4086 if (TREE_CODE (t) == CASE_LABEL_EXPR)
4089 while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4090 && is_gimple_min_invariant (TREE_OPERAND (t, 1)))
4091 || TREE_CODE (t) == COMPONENT_REF
4092 || TREE_CODE (t) == REALPART_EXPR
4093 || TREE_CODE (t) == IMAGPART_EXPR)
4094 t = TREE_OPERAND (t, 0);
4103 /* Called via walk_gimple_stmt. Verify tree sharing. */
4106 verify_node_sharing (tree *tp, int *walk_subtrees, void *data)
4108 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
4109 struct pointer_set_t *visited = (struct pointer_set_t *) wi->info;
4111 if (tree_node_can_be_shared (*tp))
4113 *walk_subtrees = false;
4117 if (pointer_set_insert (visited, *tp))
4124 static bool eh_error_found;
4126 verify_eh_throw_stmt_node (void **slot, void *data)
4128 struct throw_stmt_node *node = (struct throw_stmt_node *)*slot;
4129 struct pointer_set_t *visited = (struct pointer_set_t *) data;
4131 if (!pointer_set_contains (visited, node->stmt))
4133 error ("Dead STMT in EH table");
4134 debug_gimple_stmt (node->stmt);
4135 eh_error_found = true;
4141 /* Verify the GIMPLE statements in every basic block. */
4147 gimple_stmt_iterator gsi;
4149 struct pointer_set_t *visited, *visited_stmts;
4151 struct walk_stmt_info wi;
4153 timevar_push (TV_TREE_STMT_VERIFY);
4154 visited = pointer_set_create ();
4155 visited_stmts = pointer_set_create ();
4157 memset (&wi, 0, sizeof (wi));
4158 wi.info = (void *) visited;
4165 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4167 phi = gsi_stmt (gsi);
4168 pointer_set_insert (visited_stmts, phi);
4169 if (gimple_bb (phi) != bb)
4171 error ("gimple_bb (phi) is set to a wrong basic block");
4175 for (i = 0; i < gimple_phi_num_args (phi); i++)
4177 tree t = gimple_phi_arg_def (phi, i);
4182 error ("missing PHI def");
4183 debug_gimple_stmt (phi);
4187 /* Addressable variables do have SSA_NAMEs but they
4188 are not considered gimple values. */
4189 else if (TREE_CODE (t) != SSA_NAME
4190 && TREE_CODE (t) != FUNCTION_DECL
4191 && !is_gimple_min_invariant (t))
4193 error ("PHI argument is not a GIMPLE value");
4194 debug_gimple_stmt (phi);
4195 debug_generic_expr (t);
4199 addr = walk_tree (&t, verify_node_sharing, visited, NULL);
4202 error ("incorrect sharing of tree nodes");
4203 debug_gimple_stmt (phi);
4204 debug_generic_expr (addr);
4210 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); )
4212 gimple stmt = gsi_stmt (gsi);
4214 if (gimple_code (stmt) == GIMPLE_WITH_CLEANUP_EXPR
4215 || gimple_code (stmt) == GIMPLE_BIND)
4217 error ("invalid GIMPLE statement");
4218 debug_gimple_stmt (stmt);
4222 pointer_set_insert (visited_stmts, stmt);
4224 if (gimple_bb (stmt) != bb)
4226 error ("gimple_bb (stmt) is set to a wrong basic block");
4230 if (gimple_code (stmt) == GIMPLE_LABEL)
4232 tree decl = gimple_label_label (stmt);
4233 int uid = LABEL_DECL_UID (decl);
4236 || VEC_index (basic_block, label_to_block_map, uid) != bb)
4238 error ("incorrect entry in label_to_block_map.\n");
4243 err |= verify_stmt (&gsi);
4244 addr = walk_gimple_op (gsi_stmt (gsi), verify_node_sharing, &wi);
4247 error ("incorrect sharing of tree nodes");
4248 debug_gimple_stmt (stmt);
4249 debug_generic_expr (addr);
4256 eh_error_found = false;
4257 if (get_eh_throw_stmt_table (cfun))
4258 htab_traverse (get_eh_throw_stmt_table (cfun),
4259 verify_eh_throw_stmt_node,
4262 if (err | eh_error_found)
4263 internal_error ("verify_stmts failed");
4265 pointer_set_destroy (visited);
4266 pointer_set_destroy (visited_stmts);
4267 verify_histograms ();
4268 timevar_pop (TV_TREE_STMT_VERIFY);
4272 /* Verifies that the flow information is OK. */
4275 gimple_verify_flow_info (void)
4279 gimple_stmt_iterator gsi;
4284 if (ENTRY_BLOCK_PTR->il.gimple)
4286 error ("ENTRY_BLOCK has IL associated with it");
4290 if (EXIT_BLOCK_PTR->il.gimple)
4292 error ("EXIT_BLOCK has IL associated with it");
4296 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4297 if (e->flags & EDGE_FALLTHRU)
4299 error ("fallthru to exit from bb %d", e->src->index);
4305 bool found_ctrl_stmt = false;
4309 /* Skip labels on the start of basic block. */
4310 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4313 gimple prev_stmt = stmt;
4315 stmt = gsi_stmt (gsi);
4317 if (gimple_code (stmt) != GIMPLE_LABEL)
4320 label = gimple_label_label (stmt);
4321 if (prev_stmt && DECL_NONLOCAL (label))
4323 error ("nonlocal label ");
4324 print_generic_expr (stderr, label, 0);
4325 fprintf (stderr, " is not first in a sequence of labels in bb %d",
4330 if (label_to_block (label) != bb)
4333 print_generic_expr (stderr, label, 0);
4334 fprintf (stderr, " to block does not match in bb %d",
4339 if (decl_function_context (label) != current_function_decl)
4342 print_generic_expr (stderr, label, 0);
4343 fprintf (stderr, " has incorrect context in bb %d",
4349 /* Verify that body of basic block BB is free of control flow. */
4350 for (; !gsi_end_p (gsi); gsi_next (&gsi))
4352 gimple stmt = gsi_stmt (gsi);
4354 if (found_ctrl_stmt)
4356 error ("control flow in the middle of basic block %d",
4361 if (stmt_ends_bb_p (stmt))
4362 found_ctrl_stmt = true;
4364 if (gimple_code (stmt) == GIMPLE_LABEL)
4367 print_generic_expr (stderr, gimple_label_label (stmt), 0);
4368 fprintf (stderr, " in the middle of basic block %d", bb->index);
4373 gsi = gsi_last_bb (bb);
4374 if (gsi_end_p (gsi))
4377 stmt = gsi_stmt (gsi);
4379 err |= verify_eh_edges (stmt);
4381 if (is_ctrl_stmt (stmt))
4383 FOR_EACH_EDGE (e, ei, bb->succs)
4384 if (e->flags & EDGE_FALLTHRU)
4386 error ("fallthru edge after a control statement in bb %d",
4392 if (gimple_code (stmt) != GIMPLE_COND)
4394 /* Verify that there are no edges with EDGE_TRUE/FALSE_FLAG set
4395 after anything else but if statement. */
4396 FOR_EACH_EDGE (e, ei, bb->succs)
4397 if (e->flags & (EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))
4399 error ("true/false edge after a non-GIMPLE_COND in bb %d",
4405 switch (gimple_code (stmt))
4412 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
4416 || !(true_edge->flags & EDGE_TRUE_VALUE)
4417 || !(false_edge->flags & EDGE_FALSE_VALUE)
4418 || (true_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4419 || (false_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4420 || EDGE_COUNT (bb->succs) >= 3)
4422 error ("wrong outgoing edge flags at end of bb %d",
4430 if (simple_goto_p (stmt))
4432 error ("explicit goto at end of bb %d", bb->index);
4437 /* FIXME. We should double check that the labels in the
4438 destination blocks have their address taken. */
4439 FOR_EACH_EDGE (e, ei, bb->succs)
4440 if ((e->flags & (EDGE_FALLTHRU | EDGE_TRUE_VALUE
4441 | EDGE_FALSE_VALUE))
4442 || !(e->flags & EDGE_ABNORMAL))
4444 error ("wrong outgoing edge flags at end of bb %d",
4452 if (!single_succ_p (bb)
4453 || (single_succ_edge (bb)->flags
4454 & (EDGE_FALLTHRU | EDGE_ABNORMAL
4455 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4457 error ("wrong outgoing edge flags at end of bb %d", bb->index);
4460 if (single_succ (bb) != EXIT_BLOCK_PTR)
4462 error ("return edge does not point to exit in bb %d",
4474 n = gimple_switch_num_labels (stmt);
4476 /* Mark all the destination basic blocks. */
4477 for (i = 0; i < n; ++i)
4479 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4480 basic_block label_bb = label_to_block (lab);
4481 gcc_assert (!label_bb->aux || label_bb->aux == (void *)1);
4482 label_bb->aux = (void *)1;
4485 /* Verify that the case labels are sorted. */
4486 prev = gimple_switch_label (stmt, 0);
4487 for (i = 1; i < n; ++i)
4489 tree c = gimple_switch_label (stmt, i);
4492 error ("found default case not at the start of "
4498 && !tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c)))
4500 error ("case labels not sorted: ");
4501 print_generic_expr (stderr, prev, 0);
4502 fprintf (stderr," is greater than ");
4503 print_generic_expr (stderr, c, 0);
4504 fprintf (stderr," but comes before it.\n");
4509 /* VRP will remove the default case if it can prove it will
4510 never be executed. So do not verify there always exists
4511 a default case here. */
4513 FOR_EACH_EDGE (e, ei, bb->succs)
4517 error ("extra outgoing edge %d->%d",
4518 bb->index, e->dest->index);
4522 e->dest->aux = (void *)2;
4523 if ((e->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL
4524 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4526 error ("wrong outgoing edge flags at end of bb %d",
4532 /* Check that we have all of them. */
4533 for (i = 0; i < n; ++i)
4535 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4536 basic_block label_bb = label_to_block (lab);
4538 if (label_bb->aux != (void *)2)
4540 error ("missing edge %i->%i", bb->index, label_bb->index);
4545 FOR_EACH_EDGE (e, ei, bb->succs)
4546 e->dest->aux = (void *)0;
4553 if (dom_info_state (CDI_DOMINATORS) >= DOM_NO_FAST_QUERY)
4554 verify_dominators (CDI_DOMINATORS);
4560 /* Updates phi nodes after creating a forwarder block joined
4561 by edge FALLTHRU. */
4564 gimple_make_forwarder_block (edge fallthru)
4568 basic_block dummy, bb;
4570 gimple_stmt_iterator gsi;
4572 dummy = fallthru->src;
4573 bb = fallthru->dest;
4575 if (single_pred_p (bb))
4578 /* If we redirected a branch we must create new PHI nodes at the
4580 for (gsi = gsi_start_phis (dummy); !gsi_end_p (gsi); gsi_next (&gsi))
4582 gimple phi, new_phi;
4584 phi = gsi_stmt (gsi);
4585 var = gimple_phi_result (phi);
4586 new_phi = create_phi_node (var, bb);
4587 SSA_NAME_DEF_STMT (var) = new_phi;
4588 gimple_phi_set_result (phi, make_ssa_name (SSA_NAME_VAR (var), phi));
4589 add_phi_arg (new_phi, gimple_phi_result (phi), fallthru);
4592 /* Add the arguments we have stored on edges. */
4593 FOR_EACH_EDGE (e, ei, bb->preds)
4598 flush_pending_stmts (e);
4603 /* Return a non-special label in the head of basic block BLOCK.
4604 Create one if it doesn't exist. */
4607 gimple_block_label (basic_block bb)
4609 gimple_stmt_iterator i, s = gsi_start_bb (bb);
4614 for (i = s; !gsi_end_p (i); first = false, gsi_next (&i))
4616 stmt = gsi_stmt (i);
4617 if (gimple_code (stmt) != GIMPLE_LABEL)
4619 label = gimple_label_label (stmt);
4620 if (!DECL_NONLOCAL (label))
4623 gsi_move_before (&i, &s);
4628 label = create_artificial_label ();
4629 stmt = gimple_build_label (label);
4630 gsi_insert_before (&s, stmt, GSI_NEW_STMT);
4635 /* Attempt to perform edge redirection by replacing a possibly complex
4636 jump instruction by a goto or by removing the jump completely.
4637 This can apply only if all edges now point to the same block. The
4638 parameters and return values are equivalent to
4639 redirect_edge_and_branch. */
4642 gimple_try_redirect_by_replacing_jump (edge e, basic_block target)
4644 basic_block src = e->src;
4645 gimple_stmt_iterator i;
4648 /* We can replace or remove a complex jump only when we have exactly
4650 if (EDGE_COUNT (src->succs) != 2
4651 /* Verify that all targets will be TARGET. Specifically, the
4652 edge that is not E must also go to TARGET. */
4653 || EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)
4656 i = gsi_last_bb (src);
4660 stmt = gsi_stmt (i);
4662 if (gimple_code (stmt) == GIMPLE_COND || gimple_code (stmt) == GIMPLE_SWITCH)
4664 gsi_remove (&i, true);
4665 e = ssa_redirect_edge (e, target);
4666 e->flags = EDGE_FALLTHRU;
4674 /* Redirect E to DEST. Return NULL on failure. Otherwise, return the
4675 edge representing the redirected branch. */
4678 gimple_redirect_edge_and_branch (edge e, basic_block dest)
4680 basic_block bb = e->src;
4681 gimple_stmt_iterator gsi;
4685 if (e->flags & EDGE_ABNORMAL)
4688 if (e->src != ENTRY_BLOCK_PTR
4689 && (ret = gimple_try_redirect_by_replacing_jump (e, dest)))
4692 if (e->dest == dest)
4695 gsi = gsi_last_bb (bb);
4696 stmt = gsi_end_p (gsi) ? NULL : gsi_stmt (gsi);
4698 switch (stmt ? gimple_code (stmt) : ERROR_MARK)
4701 /* For COND_EXPR, we only need to redirect the edge. */
4705 /* No non-abnormal edges should lead from a non-simple goto, and
4706 simple ones should be represented implicitly. */
4711 tree label = gimple_block_label (dest);
4712 tree cases = get_cases_for_edge (e, stmt);
4714 /* If we have a list of cases associated with E, then use it
4715 as it's a lot faster than walking the entire case vector. */
4718 edge e2 = find_edge (e->src, dest);
4725 CASE_LABEL (cases) = label;
4726 cases = TREE_CHAIN (cases);
4729 /* If there was already an edge in the CFG, then we need
4730 to move all the cases associated with E to E2. */
4733 tree cases2 = get_cases_for_edge (e2, stmt);
4735 TREE_CHAIN (last) = TREE_CHAIN (cases2);
4736 TREE_CHAIN (cases2) = first;
4741 size_t i, n = gimple_switch_num_labels (stmt);
4743 for (i = 0; i < n; i++)
4745 tree elt = gimple_switch_label (stmt, i);
4746 if (label_to_block (CASE_LABEL (elt)) == e->dest)
4747 CASE_LABEL (elt) = label;
4755 gsi_remove (&gsi, true);
4756 e->flags |= EDGE_FALLTHRU;
4759 case GIMPLE_OMP_RETURN:
4760 case GIMPLE_OMP_CONTINUE:
4761 case GIMPLE_OMP_SECTIONS_SWITCH:
4762 case GIMPLE_OMP_FOR:
4763 /* The edges from OMP constructs can be simply redirected. */
4767 /* Otherwise it must be a fallthru edge, and we don't need to
4768 do anything besides redirecting it. */
4769 gcc_assert (e->flags & EDGE_FALLTHRU);
4773 /* Update/insert PHI nodes as necessary. */
4775 /* Now update the edges in the CFG. */
4776 e = ssa_redirect_edge (e, dest);
4781 /* Returns true if it is possible to remove edge E by redirecting
4782 it to the destination of the other edge from E->src. */
4785 gimple_can_remove_branch_p (const_edge e)
4787 if (e->flags & EDGE_ABNORMAL)
4793 /* Simple wrapper, as we can always redirect fallthru edges. */
4796 gimple_redirect_edge_and_branch_force (edge e, basic_block dest)
4798 e = gimple_redirect_edge_and_branch (e, dest);
4805 /* Splits basic block BB after statement STMT (but at least after the
4806 labels). If STMT is NULL, BB is split just after the labels. */
4809 gimple_split_block (basic_block bb, void *stmt)
4811 gimple_stmt_iterator gsi;
4812 gimple_stmt_iterator gsi_tgt;
4819 new_bb = create_empty_bb (bb);
4821 /* Redirect the outgoing edges. */
4822 new_bb->succs = bb->succs;
4824 FOR_EACH_EDGE (e, ei, new_bb->succs)
4827 if (stmt && gimple_code ((gimple) stmt) == GIMPLE_LABEL)
4830 /* Move everything from GSI to the new basic block. */
4831 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4833 act = gsi_stmt (gsi);
4834 if (gimple_code (act) == GIMPLE_LABEL)
4847 if (gsi_end_p (gsi))
4850 /* Split the statement list - avoid re-creating new containers as this
4851 brings ugly quadratic memory consumption in the inliner.
4852 (We are still quadratic since we need to update stmt BB pointers,
4854 list = gsi_split_seq_before (&gsi);
4855 set_bb_seq (new_bb, list);
4856 for (gsi_tgt = gsi_start (list);
4857 !gsi_end_p (gsi_tgt); gsi_next (&gsi_tgt))
4858 gimple_set_bb (gsi_stmt (gsi_tgt), new_bb);
4864 /* Moves basic block BB after block AFTER. */
4867 gimple_move_block_after (basic_block bb, basic_block after)
4869 if (bb->prev_bb == after)
4873 link_block (bb, after);
4879 /* Return true if basic_block can be duplicated. */
4882 gimple_can_duplicate_bb_p (const_basic_block bb ATTRIBUTE_UNUSED)
4887 /* Create a duplicate of the basic block BB. NOTE: This does not
4888 preserve SSA form. */
4891 gimple_duplicate_bb (basic_block bb)
4894 gimple_stmt_iterator gsi, gsi_tgt;
4895 gimple_seq phis = phi_nodes (bb);
4896 gimple phi, stmt, copy;
4898 new_bb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb);
4900 /* Copy the PHI nodes. We ignore PHI node arguments here because
4901 the incoming edges have not been setup yet. */
4902 for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
4904 phi = gsi_stmt (gsi);
4905 copy = create_phi_node (gimple_phi_result (phi), new_bb);
4906 create_new_def_for (gimple_phi_result (copy), copy,
4907 gimple_phi_result_ptr (copy));
4910 gsi_tgt = gsi_start_bb (new_bb);
4911 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4913 def_operand_p def_p;
4914 ssa_op_iter op_iter;
4917 stmt = gsi_stmt (gsi);
4918 if (gimple_code (stmt) == GIMPLE_LABEL)
4921 /* Create a new copy of STMT and duplicate STMT's virtual
4923 copy = gimple_copy (stmt);
4924 gsi_insert_after (&gsi_tgt, copy, GSI_NEW_STMT);
4925 copy_virtual_operands (copy, stmt);
4926 region = lookup_stmt_eh_region (stmt);
4928 add_stmt_to_eh_region (copy, region);
4929 gimple_duplicate_stmt_histograms (cfun, copy, cfun, stmt);
4931 /* Create new names for all the definitions created by COPY and
4932 add replacement mappings for each new name. */
4933 FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS)
4934 create_new_def_for (DEF_FROM_PTR (def_p), copy, def_p);
4940 /* Adds phi node arguments for edge E_COPY after basic block duplication. */
4943 add_phi_args_after_copy_edge (edge e_copy)
4945 basic_block bb, bb_copy = e_copy->src, dest;
4948 gimple phi, phi_copy;
4950 gimple_stmt_iterator psi, psi_copy;
4952 if (gimple_seq_empty_p (phi_nodes (e_copy->dest)))
4955 bb = bb_copy->flags & BB_DUPLICATED ? get_bb_original (bb_copy) : bb_copy;
4957 if (e_copy->dest->flags & BB_DUPLICATED)
4958 dest = get_bb_original (e_copy->dest);
4960 dest = e_copy->dest;
4962 e = find_edge (bb, dest);
4965 /* During loop unrolling the target of the latch edge is copied.
4966 In this case we are not looking for edge to dest, but to
4967 duplicated block whose original was dest. */
4968 FOR_EACH_EDGE (e, ei, bb->succs)
4970 if ((e->dest->flags & BB_DUPLICATED)
4971 && get_bb_original (e->dest) == dest)
4975 gcc_assert (e != NULL);
4978 for (psi = gsi_start_phis (e->dest),
4979 psi_copy = gsi_start_phis (e_copy->dest);
4981 gsi_next (&psi), gsi_next (&psi_copy))
4983 phi = gsi_stmt (psi);
4984 phi_copy = gsi_stmt (psi_copy);
4985 def = PHI_ARG_DEF_FROM_EDGE (phi, e);
4986 add_phi_arg (phi_copy, def, e_copy);
4991 /* Basic block BB_COPY was created by code duplication. Add phi node
4992 arguments for edges going out of BB_COPY. The blocks that were
4993 duplicated have BB_DUPLICATED set. */
4996 add_phi_args_after_copy_bb (basic_block bb_copy)
5001 FOR_EACH_EDGE (e_copy, ei, bb_copy->succs)
5003 add_phi_args_after_copy_edge (e_copy);
5007 /* Blocks in REGION_COPY array of length N_REGION were created by
5008 duplication of basic blocks. Add phi node arguments for edges
5009 going from these blocks. If E_COPY is not NULL, also add
5010 phi node arguments for its destination.*/
5013 add_phi_args_after_copy (basic_block *region_copy, unsigned n_region,
5018 for (i = 0; i < n_region; i++)
5019 region_copy[i]->flags |= BB_DUPLICATED;
5021 for (i = 0; i < n_region; i++)
5022 add_phi_args_after_copy_bb (region_copy[i]);
5024 add_phi_args_after_copy_edge (e_copy);
5026 for (i = 0; i < n_region; i++)
5027 region_copy[i]->flags &= ~BB_DUPLICATED;
5030 /* Duplicates a REGION (set of N_REGION basic blocks) with just a single
5031 important exit edge EXIT. By important we mean that no SSA name defined
5032 inside region is live over the other exit edges of the region. All entry
5033 edges to the region must go to ENTRY->dest. The edge ENTRY is redirected
5034 to the duplicate of the region. SSA form, dominance and loop information
5035 is updated. The new basic blocks are stored to REGION_COPY in the same
5036 order as they had in REGION, provided that REGION_COPY is not NULL.
5037 The function returns false if it is unable to copy the region,
5041 gimple_duplicate_sese_region (edge entry, edge exit,
5042 basic_block *region, unsigned n_region,
5043 basic_block *region_copy)
5046 bool free_region_copy = false, copying_header = false;
5047 struct loop *loop = entry->dest->loop_father;
5049 VEC (basic_block, heap) *doms;
5051 int total_freq = 0, entry_freq = 0;
5052 gcov_type total_count = 0, entry_count = 0;
5054 if (!can_copy_bbs_p (region, n_region))
5057 /* Some sanity checking. Note that we do not check for all possible
5058 missuses of the functions. I.e. if you ask to copy something weird,
5059 it will work, but the state of structures probably will not be
5061 for (i = 0; i < n_region; i++)
5063 /* We do not handle subloops, i.e. all the blocks must belong to the
5065 if (region[i]->loop_father != loop)
5068 if (region[i] != entry->dest
5069 && region[i] == loop->header)
5073 set_loop_copy (loop, loop);
5075 /* In case the function is used for loop header copying (which is the primary
5076 use), ensure that EXIT and its copy will be new latch and entry edges. */
5077 if (loop->header == entry->dest)
5079 copying_header = true;
5080 set_loop_copy (loop, loop_outer (loop));
5082 if (!dominated_by_p (CDI_DOMINATORS, loop->latch, exit->src))
5085 for (i = 0; i < n_region; i++)
5086 if (region[i] != exit->src
5087 && dominated_by_p (CDI_DOMINATORS, region[i], exit->src))
5093 region_copy = XNEWVEC (basic_block, n_region);
5094 free_region_copy = true;
5097 gcc_assert (!need_ssa_update_p ());
5099 /* Record blocks outside the region that are dominated by something
5102 initialize_original_copy_tables ();
5104 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5106 if (entry->dest->count)
5108 total_count = entry->dest->count;
5109 entry_count = entry->count;
5110 /* Fix up corner cases, to avoid division by zero or creation of negative
5112 if (entry_count > total_count)
5113 entry_count = total_count;
5117 total_freq = entry->dest->frequency;
5118 entry_freq = EDGE_FREQUENCY (entry);
5119 /* Fix up corner cases, to avoid division by zero or creation of negative
5121 if (total_freq == 0)
5123 else if (entry_freq > total_freq)
5124 entry_freq = total_freq;
5127 copy_bbs (region, n_region, region_copy, &exit, 1, &exit_copy, loop,
5128 split_edge_bb_loc (entry));
5131 scale_bbs_frequencies_gcov_type (region, n_region,
5132 total_count - entry_count,
5134 scale_bbs_frequencies_gcov_type (region_copy, n_region, entry_count,
5139 scale_bbs_frequencies_int (region, n_region, total_freq - entry_freq,
5141 scale_bbs_frequencies_int (region_copy, n_region, entry_freq, total_freq);
5146 loop->header = exit->dest;
5147 loop->latch = exit->src;
5150 /* Redirect the entry and add the phi node arguments. */
5151 redirected = redirect_edge_and_branch (entry, get_bb_copy (entry->dest));
5152 gcc_assert (redirected != NULL);
5153 flush_pending_stmts (entry);
5155 /* Concerning updating of dominators: We must recount dominators
5156 for entry block and its copy. Anything that is outside of the
5157 region, but was dominated by something inside needs recounting as
5159 set_immediate_dominator (CDI_DOMINATORS, entry->dest, entry->src);
5160 VEC_safe_push (basic_block, heap, doms, get_bb_original (entry->dest));
5161 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5162 VEC_free (basic_block, heap, doms);
5164 /* Add the other PHI node arguments. */
5165 add_phi_args_after_copy (region_copy, n_region, NULL);
5167 /* Update the SSA web. */
5168 update_ssa (TODO_update_ssa);
5170 if (free_region_copy)
5173 free_original_copy_tables ();
5177 /* Duplicates REGION consisting of N_REGION blocks. The new blocks
5178 are stored to REGION_COPY in the same order in that they appear
5179 in REGION, if REGION_COPY is not NULL. ENTRY is the entry to
5180 the region, EXIT an exit from it. The condition guarding EXIT
5181 is moved to ENTRY. Returns true if duplication succeeds, false
5207 gimple_duplicate_sese_tail (edge entry ATTRIBUTE_UNUSED, edge exit ATTRIBUTE_UNUSED,
5208 basic_block *region ATTRIBUTE_UNUSED, unsigned n_region ATTRIBUTE_UNUSED,
5209 basic_block *region_copy ATTRIBUTE_UNUSED)
5212 bool free_region_copy = false;
5213 struct loop *loop = exit->dest->loop_father;
5214 struct loop *orig_loop = entry->dest->loop_father;
5215 basic_block switch_bb, entry_bb, nentry_bb;
5216 VEC (basic_block, heap) *doms;
5217 int total_freq = 0, exit_freq = 0;
5218 gcov_type total_count = 0, exit_count = 0;
5219 edge exits[2], nexits[2], e;
5220 gimple_stmt_iterator gsi;
5224 gcc_assert (EDGE_COUNT (exit->src->succs) == 2);
5226 exits[1] = EDGE_SUCC (exit->src, EDGE_SUCC (exit->src, 0) == exit);
5228 if (!can_copy_bbs_p (region, n_region))
5231 /* Some sanity checking. Note that we do not check for all possible
5232 missuses of the functions. I.e. if you ask to copy something weird
5233 (e.g., in the example, if there is a jump from inside to the middle
5234 of some_code, or come_code defines some of the values used in cond)
5235 it will work, but the resulting code will not be correct. */
5236 for (i = 0; i < n_region; i++)
5238 /* We do not handle subloops, i.e. all the blocks must belong to the
5240 if (region[i]->loop_father != orig_loop)
5243 if (region[i] == orig_loop->latch)
5247 initialize_original_copy_tables ();
5248 set_loop_copy (orig_loop, loop);
5252 region_copy = XNEWVEC (basic_block, n_region);
5253 free_region_copy = true;
5256 gcc_assert (!need_ssa_update_p ());
5258 /* Record blocks outside the region that are dominated by something
5260 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5262 if (exit->src->count)
5264 total_count = exit->src->count;
5265 exit_count = exit->count;
5266 /* Fix up corner cases, to avoid division by zero or creation of negative
5268 if (exit_count > total_count)
5269 exit_count = total_count;
5273 total_freq = exit->src->frequency;
5274 exit_freq = EDGE_FREQUENCY (exit);
5275 /* Fix up corner cases, to avoid division by zero or creation of negative
5277 if (total_freq == 0)
5279 if (exit_freq > total_freq)
5280 exit_freq = total_freq;
5283 copy_bbs (region, n_region, region_copy, exits, 2, nexits, orig_loop,
5284 split_edge_bb_loc (exit));
5287 scale_bbs_frequencies_gcov_type (region, n_region,
5288 total_count - exit_count,
5290 scale_bbs_frequencies_gcov_type (region_copy, n_region, exit_count,
5295 scale_bbs_frequencies_int (region, n_region, total_freq - exit_freq,
5297 scale_bbs_frequencies_int (region_copy, n_region, exit_freq, total_freq);
5300 /* Create the switch block, and put the exit condition to it. */
5301 entry_bb = entry->dest;
5302 nentry_bb = get_bb_copy (entry_bb);
5303 if (!last_stmt (entry->src)
5304 || !stmt_ends_bb_p (last_stmt (entry->src)))
5305 switch_bb = entry->src;
5307 switch_bb = split_edge (entry);
5308 set_immediate_dominator (CDI_DOMINATORS, nentry_bb, switch_bb);
5310 gsi = gsi_last_bb (switch_bb);
5311 cond_stmt = last_stmt (exit->src);
5312 gcc_assert (gimple_code (cond_stmt) == GIMPLE_COND);
5313 cond_stmt = gimple_copy (cond_stmt);
5314 gimple_cond_set_lhs (cond_stmt, unshare_expr (gimple_cond_lhs (cond_stmt)));
5315 gimple_cond_set_rhs (cond_stmt, unshare_expr (gimple_cond_rhs (cond_stmt)));
5316 gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT);
5318 sorig = single_succ_edge (switch_bb);
5319 sorig->flags = exits[1]->flags;
5320 snew = make_edge (switch_bb, nentry_bb, exits[0]->flags);
5322 /* Register the new edge from SWITCH_BB in loop exit lists. */
5323 rescan_loop_exit (snew, true, false);
5325 /* Add the PHI node arguments. */
5326 add_phi_args_after_copy (region_copy, n_region, snew);
5328 /* Get rid of now superfluous conditions and associated edges (and phi node
5330 e = redirect_edge_and_branch (exits[0], exits[1]->dest);
5331 PENDING_STMT (e) = NULL;
5332 e = redirect_edge_and_branch (nexits[1], nexits[0]->dest);
5333 PENDING_STMT (e) = NULL;
5335 /* Anything that is outside of the region, but was dominated by something
5336 inside needs to update dominance info. */
5337 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5338 VEC_free (basic_block, heap, doms);
5340 /* Update the SSA web. */
5341 update_ssa (TODO_update_ssa);
5343 if (free_region_copy)
5346 free_original_copy_tables ();
5350 /* Add all the blocks dominated by ENTRY to the array BBS_P. Stop
5351 adding blocks when the dominator traversal reaches EXIT. This
5352 function silently assumes that ENTRY strictly dominates EXIT. */
5355 gather_blocks_in_sese_region (basic_block entry, basic_block exit,
5356 VEC(basic_block,heap) **bbs_p)
5360 for (son = first_dom_son (CDI_DOMINATORS, entry);
5362 son = next_dom_son (CDI_DOMINATORS, son))
5364 VEC_safe_push (basic_block, heap, *bbs_p, son);
5366 gather_blocks_in_sese_region (son, exit, bbs_p);
5370 /* Replaces *TP with a duplicate (belonging to function TO_CONTEXT).
5371 The duplicates are recorded in VARS_MAP. */
5374 replace_by_duplicate_decl (tree *tp, struct pointer_map_t *vars_map,
5377 tree t = *tp, new_t;
5378 struct function *f = DECL_STRUCT_FUNCTION (to_context);
5381 if (DECL_CONTEXT (t) == to_context)
5384 loc = pointer_map_contains (vars_map, t);
5388 loc = pointer_map_insert (vars_map, t);
5392 new_t = copy_var_decl (t, DECL_NAME (t), TREE_TYPE (t));
5393 f->local_decls = tree_cons (NULL_TREE, new_t, f->local_decls);
5397 gcc_assert (TREE_CODE (t) == CONST_DECL);
5398 new_t = copy_node (t);
5400 DECL_CONTEXT (new_t) = to_context;
5405 new_t = (tree) *loc;
5411 /* Creates an ssa name in TO_CONTEXT equivalent to NAME.
5412 VARS_MAP maps old ssa names and var_decls to the new ones. */
5415 replace_ssa_name (tree name, struct pointer_map_t *vars_map,
5419 tree new_name, decl = SSA_NAME_VAR (name);
5421 gcc_assert (is_gimple_reg (name));
5423 loc = pointer_map_contains (vars_map, name);
5427 replace_by_duplicate_decl (&decl, vars_map, to_context);
5429 push_cfun (DECL_STRUCT_FUNCTION (to_context));
5430 if (gimple_in_ssa_p (cfun))
5431 add_referenced_var (decl);
5433 new_name = make_ssa_name (decl, SSA_NAME_DEF_STMT (name));
5434 if (SSA_NAME_IS_DEFAULT_DEF (name))
5435 set_default_def (decl, new_name);
5438 loc = pointer_map_insert (vars_map, name);
5442 new_name = (tree) *loc;
5453 struct pointer_map_t *vars_map;
5454 htab_t new_label_map;
5458 /* Helper for move_block_to_fn. Set TREE_BLOCK in every expression
5459 contained in *TP if it has been ORIG_BLOCK previously and change the
5460 DECL_CONTEXT of every local variable referenced in *TP. */
5463 move_stmt_op (tree *tp, int *walk_subtrees, void *data)
5465 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
5466 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5470 /* We should never have TREE_BLOCK set on non-statements. */
5471 gcc_assert (!TREE_BLOCK (t));
5473 else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
5475 if (TREE_CODE (t) == SSA_NAME)
5476 *tp = replace_ssa_name (t, p->vars_map, p->to_context);
5477 else if (TREE_CODE (t) == LABEL_DECL)
5479 if (p->new_label_map)
5481 struct tree_map in, *out;
5483 out = (struct tree_map *)
5484 htab_find_with_hash (p->new_label_map, &in, DECL_UID (t));
5489 DECL_CONTEXT (t) = p->to_context;
5491 else if (p->remap_decls_p)
5493 /* Replace T with its duplicate. T should no longer appear in the
5494 parent function, so this looks wasteful; however, it may appear
5495 in referenced_vars, and more importantly, as virtual operands of
5496 statements, and in alias lists of other variables. It would be
5497 quite difficult to expunge it from all those places. ??? It might
5498 suffice to do this for addressable variables. */
5499 if ((TREE_CODE (t) == VAR_DECL
5500 && !is_global_var (t))
5501 || TREE_CODE (t) == CONST_DECL)
5502 replace_by_duplicate_decl (tp, p->vars_map, p->to_context);
5505 && gimple_in_ssa_p (cfun))
5507 push_cfun (DECL_STRUCT_FUNCTION (p->to_context));
5508 add_referenced_var (*tp);
5514 else if (TYPE_P (t))
5520 /* Like move_stmt_op, but for gimple statements.
5522 Helper for move_block_to_fn. Set GIMPLE_BLOCK in every expression
5523 contained in the current statement in *GSI_P and change the
5524 DECL_CONTEXT of every local variable referenced in the current
5528 move_stmt_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
5529 struct walk_stmt_info *wi)
5531 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5532 gimple stmt = gsi_stmt (*gsi_p);
5533 tree block = gimple_block (stmt);
5535 if (p->orig_block == NULL_TREE
5536 || block == p->orig_block
5537 || block == NULL_TREE)
5538 gimple_set_block (stmt, p->new_block);
5539 #ifdef ENABLE_CHECKING
5540 else if (block != p->new_block)
5542 while (block && block != p->orig_block)
5543 block = BLOCK_SUPERCONTEXT (block);
5548 if (is_gimple_omp (stmt)
5549 && gimple_code (stmt) != GIMPLE_OMP_RETURN
5550 && gimple_code (stmt) != GIMPLE_OMP_CONTINUE)
5552 /* Do not remap variables inside OMP directives. Variables
5553 referenced in clauses and directive header belong to the
5554 parent function and should not be moved into the child
5556 bool save_remap_decls_p = p->remap_decls_p;
5557 p->remap_decls_p = false;
5558 *handled_ops_p = true;
5560 walk_gimple_seq (gimple_omp_body (stmt), move_stmt_r, move_stmt_op, wi);
5562 p->remap_decls_p = save_remap_decls_p;
5568 /* Marks virtual operands of all statements in basic blocks BBS for
5572 mark_virtual_ops_in_bb (basic_block bb)
5574 gimple_stmt_iterator gsi;
5576 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5577 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5579 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5580 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5583 /* Marks virtual operands of all statements in basic blocks BBS for
5587 mark_virtual_ops_in_region (VEC (basic_block,heap) *bbs)
5592 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
5593 mark_virtual_ops_in_bb (bb);
5596 /* Move basic block BB from function CFUN to function DEST_FN. The
5597 block is moved out of the original linked list and placed after
5598 block AFTER in the new list. Also, the block is removed from the
5599 original array of blocks and placed in DEST_FN's array of blocks.
5600 If UPDATE_EDGE_COUNT_P is true, the edge counts on both CFGs is
5601 updated to reflect the moved edges.
5603 The local variables are remapped to new instances, VARS_MAP is used
5604 to record the mapping. */
5607 move_block_to_fn (struct function *dest_cfun, basic_block bb,
5608 basic_block after, bool update_edge_count_p,
5609 struct move_stmt_d *d, int eh_offset)
5611 struct control_flow_graph *cfg;
5614 gimple_stmt_iterator si;
5615 unsigned old_len, new_len;
5617 /* Remove BB from dominance structures. */
5618 delete_from_dominance_info (CDI_DOMINATORS, bb);
5620 remove_bb_from_loops (bb);
5622 /* Link BB to the new linked list. */
5623 move_block_after (bb, after);
5625 /* Update the edge count in the corresponding flowgraphs. */
5626 if (update_edge_count_p)
5627 FOR_EACH_EDGE (e, ei, bb->succs)
5629 cfun->cfg->x_n_edges--;
5630 dest_cfun->cfg->x_n_edges++;
5633 /* Remove BB from the original basic block array. */
5634 VEC_replace (basic_block, cfun->cfg->x_basic_block_info, bb->index, NULL);
5635 cfun->cfg->x_n_basic_blocks--;
5637 /* Grow DEST_CFUN's basic block array if needed. */
5638 cfg = dest_cfun->cfg;
5639 cfg->x_n_basic_blocks++;
5640 if (bb->index >= cfg->x_last_basic_block)
5641 cfg->x_last_basic_block = bb->index + 1;
5643 old_len = VEC_length (basic_block, cfg->x_basic_block_info);
5644 if ((unsigned) cfg->x_last_basic_block >= old_len)
5646 new_len = cfg->x_last_basic_block + (cfg->x_last_basic_block + 3) / 4;
5647 VEC_safe_grow_cleared (basic_block, gc, cfg->x_basic_block_info,
5651 VEC_replace (basic_block, cfg->x_basic_block_info,
5654 /* Remap the variables in phi nodes. */
5655 for (si = gsi_start_phis (bb); !gsi_end_p (si); )
5657 gimple phi = gsi_stmt (si);
5659 tree op = PHI_RESULT (phi);
5662 if (!is_gimple_reg (op))
5664 /* Remove the phi nodes for virtual operands (alias analysis will be
5665 run for the new function, anyway). */
5666 remove_phi_node (&si, true);
5670 SET_PHI_RESULT (phi,
5671 replace_ssa_name (op, d->vars_map, dest_cfun->decl));
5672 FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
5674 op = USE_FROM_PTR (use);
5675 if (TREE_CODE (op) == SSA_NAME)
5676 SET_USE (use, replace_ssa_name (op, d->vars_map, dest_cfun->decl));
5682 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
5684 gimple stmt = gsi_stmt (si);
5686 struct walk_stmt_info wi;
5688 memset (&wi, 0, sizeof (wi));
5690 walk_gimple_stmt (&si, move_stmt_r, move_stmt_op, &wi);
5692 if (gimple_code (stmt) == GIMPLE_LABEL)
5694 tree label = gimple_label_label (stmt);
5695 int uid = LABEL_DECL_UID (label);
5697 gcc_assert (uid > -1);
5699 old_len = VEC_length (basic_block, cfg->x_label_to_block_map);
5700 if (old_len <= (unsigned) uid)
5702 new_len = 3 * uid / 2;
5703 VEC_safe_grow_cleared (basic_block, gc,
5704 cfg->x_label_to_block_map, new_len);
5707 VEC_replace (basic_block, cfg->x_label_to_block_map, uid, bb);
5708 VEC_replace (basic_block, cfun->cfg->x_label_to_block_map, uid, NULL);
5710 gcc_assert (DECL_CONTEXT (label) == dest_cfun->decl);
5712 if (uid >= dest_cfun->cfg->last_label_uid)
5713 dest_cfun->cfg->last_label_uid = uid + 1;
5715 else if (gimple_code (stmt) == GIMPLE_RESX && eh_offset != 0)
5716 gimple_resx_set_region (stmt, gimple_resx_region (stmt) + eh_offset);
5718 region = lookup_stmt_eh_region (stmt);
5721 add_stmt_to_eh_region_fn (dest_cfun, stmt, region + eh_offset);
5722 remove_stmt_from_eh_region (stmt);
5723 gimple_duplicate_stmt_histograms (dest_cfun, stmt, cfun, stmt);
5724 gimple_remove_stmt_histograms (cfun, stmt);
5727 /* We cannot leave any operands allocated from the operand caches of
5728 the current function. */
5729 free_stmt_operands (stmt);
5730 push_cfun (dest_cfun);
5736 /* Examine the statements in BB (which is in SRC_CFUN); find and return
5737 the outermost EH region. Use REGION as the incoming base EH region. */
5740 find_outermost_region_in_block (struct function *src_cfun,
5741 basic_block bb, int region)
5743 gimple_stmt_iterator si;
5745 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
5747 gimple stmt = gsi_stmt (si);
5750 if (gimple_code (stmt) == GIMPLE_RESX)
5751 stmt_region = gimple_resx_region (stmt);
5753 stmt_region = lookup_stmt_eh_region_fn (src_cfun, stmt);
5754 if (stmt_region > 0)
5757 region = stmt_region;
5758 else if (stmt_region != region)
5760 region = eh_region_outermost (src_cfun, stmt_region, region);
5761 gcc_assert (region != -1);
5770 new_label_mapper (tree decl, void *data)
5772 htab_t hash = (htab_t) data;
5776 gcc_assert (TREE_CODE (decl) == LABEL_DECL);
5778 m = XNEW (struct tree_map);
5779 m->hash = DECL_UID (decl);
5780 m->base.from = decl;
5781 m->to = create_artificial_label ();
5782 LABEL_DECL_UID (m->to) = LABEL_DECL_UID (decl);
5783 if (LABEL_DECL_UID (m->to) >= cfun->cfg->last_label_uid)
5784 cfun->cfg->last_label_uid = LABEL_DECL_UID (m->to) + 1;
5786 slot = htab_find_slot_with_hash (hash, m, m->hash, INSERT);
5787 gcc_assert (*slot == NULL);
5794 /* Change DECL_CONTEXT of all BLOCK_VARS in block, including
5798 replace_block_vars_by_duplicates (tree block, struct pointer_map_t *vars_map,
5803 for (tp = &BLOCK_VARS (block); *tp; tp = &TREE_CHAIN (*tp))
5806 replace_by_duplicate_decl (&t, vars_map, to_context);
5809 if (TREE_CODE (*tp) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (*tp))
5811 SET_DECL_VALUE_EXPR (t, DECL_VALUE_EXPR (*tp));
5812 DECL_HAS_VALUE_EXPR_P (t) = 1;
5814 TREE_CHAIN (t) = TREE_CHAIN (*tp);
5819 for (block = BLOCK_SUBBLOCKS (block); block; block = BLOCK_CHAIN (block))
5820 replace_block_vars_by_duplicates (block, vars_map, to_context);
5823 /* Move a single-entry, single-exit region delimited by ENTRY_BB and
5824 EXIT_BB to function DEST_CFUN. The whole region is replaced by a
5825 single basic block in the original CFG and the new basic block is
5826 returned. DEST_CFUN must not have a CFG yet.
5828 Note that the region need not be a pure SESE region. Blocks inside
5829 the region may contain calls to abort/exit. The only restriction
5830 is that ENTRY_BB should be the only entry point and it must
5833 Change TREE_BLOCK of all statements in ORIG_BLOCK to the new
5834 functions outermost BLOCK, move all subblocks of ORIG_BLOCK
5835 to the new function.
5837 All local variables referenced in the region are assumed to be in
5838 the corresponding BLOCK_VARS and unexpanded variable lists
5839 associated with DEST_CFUN. */
5842 move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb,
5843 basic_block exit_bb, tree orig_block)
5845 VEC(basic_block,heap) *bbs, *dom_bbs;
5846 basic_block dom_entry = get_immediate_dominator (CDI_DOMINATORS, entry_bb);
5847 basic_block after, bb, *entry_pred, *exit_succ, abb;
5848 struct function *saved_cfun = cfun;
5849 int *entry_flag, *exit_flag, eh_offset;
5850 unsigned *entry_prob, *exit_prob;
5851 unsigned i, num_entry_edges, num_exit_edges;
5854 htab_t new_label_map;
5855 struct pointer_map_t *vars_map;
5856 struct loop *loop = entry_bb->loop_father;
5857 struct move_stmt_d d;
5859 /* If ENTRY does not strictly dominate EXIT, this cannot be an SESE
5861 gcc_assert (entry_bb != exit_bb
5863 || dominated_by_p (CDI_DOMINATORS, exit_bb, entry_bb)));
5865 /* Collect all the blocks in the region. Manually add ENTRY_BB
5866 because it won't be added by dfs_enumerate_from. */
5868 VEC_safe_push (basic_block, heap, bbs, entry_bb);
5869 gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs);
5871 /* The blocks that used to be dominated by something in BBS will now be
5872 dominated by the new block. */
5873 dom_bbs = get_dominated_by_region (CDI_DOMINATORS,
5874 VEC_address (basic_block, bbs),
5875 VEC_length (basic_block, bbs));
5877 /* Detach ENTRY_BB and EXIT_BB from CFUN->CFG. We need to remember
5878 the predecessor edges to ENTRY_BB and the successor edges to
5879 EXIT_BB so that we can re-attach them to the new basic block that
5880 will replace the region. */
5881 num_entry_edges = EDGE_COUNT (entry_bb->preds);
5882 entry_pred = (basic_block *) xcalloc (num_entry_edges, sizeof (basic_block));
5883 entry_flag = (int *) xcalloc (num_entry_edges, sizeof (int));
5884 entry_prob = XNEWVEC (unsigned, num_entry_edges);
5886 for (ei = ei_start (entry_bb->preds); (e = ei_safe_edge (ei)) != NULL;)
5888 entry_prob[i] = e->probability;
5889 entry_flag[i] = e->flags;
5890 entry_pred[i++] = e->src;
5896 num_exit_edges = EDGE_COUNT (exit_bb->succs);
5897 exit_succ = (basic_block *) xcalloc (num_exit_edges,
5898 sizeof (basic_block));
5899 exit_flag = (int *) xcalloc (num_exit_edges, sizeof (int));
5900 exit_prob = XNEWVEC (unsigned, num_exit_edges);
5902 for (ei = ei_start (exit_bb->succs); (e = ei_safe_edge (ei)) != NULL;)
5904 exit_prob[i] = e->probability;
5905 exit_flag[i] = e->flags;
5906 exit_succ[i++] = e->dest;
5918 /* Switch context to the child function to initialize DEST_FN's CFG. */
5919 gcc_assert (dest_cfun->cfg == NULL);
5920 push_cfun (dest_cfun);
5922 init_empty_tree_cfg ();
5924 /* Initialize EH information for the new function. */
5926 new_label_map = NULL;
5931 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
5932 region = find_outermost_region_in_block (saved_cfun, bb, region);
5934 init_eh_for_function ();
5937 new_label_map = htab_create (17, tree_map_hash, tree_map_eq, free);
5938 eh_offset = duplicate_eh_regions (saved_cfun, new_label_mapper,
5939 new_label_map, region, 0);
5945 /* The ssa form for virtual operands in the source function will have to
5946 be repaired. We do not care for the real operands -- the sese region
5947 must be closed with respect to those. */
5948 mark_virtual_ops_in_region (bbs);
5950 /* Move blocks from BBS into DEST_CFUN. */
5951 gcc_assert (VEC_length (basic_block, bbs) >= 2);
5952 after = dest_cfun->cfg->x_entry_block_ptr;
5953 vars_map = pointer_map_create ();
5955 memset (&d, 0, sizeof (d));
5956 d.vars_map = vars_map;
5957 d.from_context = cfun->decl;
5958 d.to_context = dest_cfun->decl;
5959 d.new_label_map = new_label_map;
5960 d.remap_decls_p = true;
5961 d.orig_block = orig_block;
5962 d.new_block = DECL_INITIAL (dest_cfun->decl);
5964 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
5966 /* No need to update edge counts on the last block. It has
5967 already been updated earlier when we detached the region from
5968 the original CFG. */
5969 move_block_to_fn (dest_cfun, bb, after, bb != exit_bb, &d, eh_offset);
5973 /* Rewire BLOCK_SUBBLOCKS of orig_block. */
5977 gcc_assert (BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
5979 BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
5980 = BLOCK_SUBBLOCKS (orig_block);
5981 for (block = BLOCK_SUBBLOCKS (orig_block);
5982 block; block = BLOCK_CHAIN (block))
5983 BLOCK_SUPERCONTEXT (block) = DECL_INITIAL (dest_cfun->decl);
5984 BLOCK_SUBBLOCKS (orig_block) = NULL_TREE;
5987 replace_block_vars_by_duplicates (DECL_INITIAL (dest_cfun->decl),
5988 vars_map, dest_cfun->decl);
5991 htab_delete (new_label_map);
5992 pointer_map_destroy (vars_map);
5994 /* Rewire the entry and exit blocks. The successor to the entry
5995 block turns into the successor of DEST_FN's ENTRY_BLOCK_PTR in
5996 the child function. Similarly, the predecessor of DEST_FN's
5997 EXIT_BLOCK_PTR turns into the predecessor of EXIT_BLOCK_PTR. We
5998 need to switch CFUN between DEST_CFUN and SAVED_CFUN so that the
5999 various CFG manipulation function get to the right CFG.
6001 FIXME, this is silly. The CFG ought to become a parameter to
6003 push_cfun (dest_cfun);
6004 make_edge (ENTRY_BLOCK_PTR, entry_bb, EDGE_FALLTHRU);
6006 make_edge (exit_bb, EXIT_BLOCK_PTR, 0);
6009 /* Back in the original function, the SESE region has disappeared,
6010 create a new basic block in its place. */
6011 bb = create_empty_bb (entry_pred[0]);
6013 add_bb_to_loop (bb, loop);
6014 for (i = 0; i < num_entry_edges; i++)
6016 e = make_edge (entry_pred[i], bb, entry_flag[i]);
6017 e->probability = entry_prob[i];
6020 for (i = 0; i < num_exit_edges; i++)
6022 e = make_edge (bb, exit_succ[i], exit_flag[i]);
6023 e->probability = exit_prob[i];
6026 set_immediate_dominator (CDI_DOMINATORS, bb, dom_entry);
6027 for (i = 0; VEC_iterate (basic_block, dom_bbs, i, abb); i++)
6028 set_immediate_dominator (CDI_DOMINATORS, abb, bb);
6029 VEC_free (basic_block, heap, dom_bbs);
6040 VEC_free (basic_block, heap, bbs);
6046 /* Dump FUNCTION_DECL FN to file FILE using FLAGS (see TDF_* in tree-pass.h)
6050 dump_function_to_file (tree fn, FILE *file, int flags)
6052 tree arg, vars, var;
6053 struct function *dsf;
6054 bool ignore_topmost_bind = false, any_var = false;
6058 fprintf (file, "%s (", lang_hooks.decl_printable_name (fn, 2));
6060 arg = DECL_ARGUMENTS (fn);
6063 print_generic_expr (file, TREE_TYPE (arg), dump_flags);
6064 fprintf (file, " ");
6065 print_generic_expr (file, arg, dump_flags);
6066 if (flags & TDF_VERBOSE)
6067 print_node (file, "", arg, 4);
6068 if (TREE_CHAIN (arg))
6069 fprintf (file, ", ");
6070 arg = TREE_CHAIN (arg);
6072 fprintf (file, ")\n");
6074 if (flags & TDF_VERBOSE)
6075 print_node (file, "", fn, 2);
6077 dsf = DECL_STRUCT_FUNCTION (fn);
6078 if (dsf && (flags & TDF_DETAILS))
6079 dump_eh_tree (file, dsf);
6081 if (flags & TDF_RAW && !gimple_has_body_p (fn))
6083 dump_node (fn, TDF_SLIM | flags, file);
6087 /* Switch CFUN to point to FN. */
6088 push_cfun (DECL_STRUCT_FUNCTION (fn));
6090 /* When GIMPLE is lowered, the variables are no longer available in
6091 BIND_EXPRs, so display them separately. */
6092 if (cfun && cfun->decl == fn && cfun->local_decls)
6094 ignore_topmost_bind = true;
6096 fprintf (file, "{\n");
6097 for (vars = cfun->local_decls; vars; vars = TREE_CHAIN (vars))
6099 var = TREE_VALUE (vars);
6101 print_generic_decl (file, var, flags);
6102 if (flags & TDF_VERBOSE)
6103 print_node (file, "", var, 4);
6104 fprintf (file, "\n");
6110 if (cfun && cfun->decl == fn && cfun->cfg && basic_block_info)
6112 /* If the CFG has been built, emit a CFG-based dump. */
6113 check_bb_profile (ENTRY_BLOCK_PTR, file);
6114 if (!ignore_topmost_bind)
6115 fprintf (file, "{\n");
6117 if (any_var && n_basic_blocks)
6118 fprintf (file, "\n");
6121 gimple_dump_bb (bb, file, 2, flags);
6123 fprintf (file, "}\n");
6124 check_bb_profile (EXIT_BLOCK_PTR, file);
6126 else if (DECL_SAVED_TREE (fn) == NULL)
6128 /* The function is now in GIMPLE form but the CFG has not been
6129 built yet. Emit the single sequence of GIMPLE statements
6130 that make up its body. */
6131 gimple_seq body = gimple_body (fn);
6133 if (gimple_seq_first_stmt (body)
6134 && gimple_seq_first_stmt (body) == gimple_seq_last_stmt (body)
6135 && gimple_code (gimple_seq_first_stmt (body)) == GIMPLE_BIND)
6136 print_gimple_seq (file, body, 0, flags);
6139 if (!ignore_topmost_bind)
6140 fprintf (file, "{\n");
6143 fprintf (file, "\n");
6145 print_gimple_seq (file, body, 2, flags);
6146 fprintf (file, "}\n");
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 gimple_dump_bb (bb, file, indent + 4, TDF_VOPS|TDF_MEMSYMS);
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 = ENTRY_BLOCK_PTR;
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 gimple_block_ends_with_call_p (basic_block bb)
6361 gimple_stmt_iterator gsi = gsi_last_bb (bb);
6362 return is_gimple_call (gsi_stmt (gsi));
6366 /* Return true if BB ends with a conditional branch. Return false,
6370 gimple_block_ends_with_condjump_p (const_basic_block bb)
6372 gimple stmt = last_stmt (CONST_CAST_BB (bb));
6373 return (stmt && gimple_code (stmt) == GIMPLE_COND);
6377 /* Return true if we need to add fake edge to exit at statement T.
6378 Helper function for gimple_flow_call_edges_add. */
6381 need_fake_edge_p (gimple t)
6383 tree fndecl = NULL_TREE;
6386 /* NORETURN and LONGJMP calls already have an edge to exit.
6387 CONST and PURE calls do not need one.
6388 We don't currently check for CONST and PURE here, although
6389 it would be a good idea, because those attributes are
6390 figured out from the RTL in mark_constant_function, and
6391 the counter incrementation code from -fprofile-arcs
6392 leads to different results from -fbranch-probabilities. */
6393 if (is_gimple_call (t))
6395 fndecl = gimple_call_fndecl (t);
6396 call_flags = gimple_call_flags (t);
6399 if (is_gimple_call (t)
6401 && DECL_BUILT_IN (fndecl)
6402 && (call_flags & ECF_NOTHROW)
6403 && !(call_flags & ECF_NORETURN)
6404 && !(call_flags & ECF_RETURNS_TWICE))
6407 if (is_gimple_call (t)
6408 && !(call_flags & ECF_NORETURN))
6411 if (gimple_code (t) == GIMPLE_ASM
6412 && (gimple_asm_volatile_p (t) || gimple_asm_input_p (t)))
6419 /* Add fake edges to the function exit for any non constant and non
6420 noreturn calls, volatile inline assembly in the bitmap of blocks
6421 specified by BLOCKS or to the whole CFG if BLOCKS is zero. Return
6422 the number of blocks that were split.
6424 The goal is to expose cases in which entering a basic block does
6425 not imply that all subsequent instructions must be executed. */
6428 gimple_flow_call_edges_add (sbitmap blocks)
6431 int blocks_split = 0;
6432 int last_bb = last_basic_block;
6433 bool check_last_block = false;
6435 if (n_basic_blocks == NUM_FIXED_BLOCKS)
6439 check_last_block = true;
6441 check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index);
6443 /* In the last basic block, before epilogue generation, there will be
6444 a fallthru edge to EXIT. Special care is required if the last insn
6445 of the last basic block is a call because make_edge folds duplicate
6446 edges, which would result in the fallthru edge also being marked
6447 fake, which would result in the fallthru edge being removed by
6448 remove_fake_edges, which would result in an invalid CFG.
6450 Moreover, we can't elide the outgoing fake edge, since the block
6451 profiler needs to take this into account in order to solve the minimal
6452 spanning tree in the case that the call doesn't return.
6454 Handle this by adding a dummy instruction in a new last basic block. */
6455 if (check_last_block)
6457 basic_block bb = EXIT_BLOCK_PTR->prev_bb;
6458 gimple_stmt_iterator gsi = gsi_last_bb (bb);
6461 if (!gsi_end_p (gsi))
6464 if (t && need_fake_edge_p (t))
6468 e = find_edge (bb, EXIT_BLOCK_PTR);
6471 gsi_insert_on_edge (e, gimple_build_nop ());
6472 gsi_commit_edge_inserts ();
6477 /* Now add fake edges to the function exit for any non constant
6478 calls since there is no way that we can determine if they will
6480 for (i = 0; i < last_bb; i++)
6482 basic_block bb = BASIC_BLOCK (i);
6483 gimple_stmt_iterator gsi;
6484 gimple stmt, last_stmt;
6489 if (blocks && !TEST_BIT (blocks, i))
6492 gsi = gsi_last_bb (bb);
6493 if (!gsi_end_p (gsi))
6495 last_stmt = gsi_stmt (gsi);
6498 stmt = gsi_stmt (gsi);
6499 if (need_fake_edge_p (stmt))
6503 /* The handling above of the final block before the
6504 epilogue should be enough to verify that there is
6505 no edge to the exit block in CFG already.
6506 Calling make_edge in such case would cause us to
6507 mark that edge as fake and remove it later. */
6508 #ifdef ENABLE_CHECKING
6509 if (stmt == last_stmt)
6511 e = find_edge (bb, EXIT_BLOCK_PTR);
6512 gcc_assert (e == NULL);
6516 /* Note that the following may create a new basic block
6517 and renumber the existing basic blocks. */
6518 if (stmt != last_stmt)
6520 e = split_block (bb, stmt);
6524 make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE);
6528 while (!gsi_end_p (gsi));
6533 verify_flow_info ();
6535 return blocks_split;
6538 /* Purge dead abnormal call edges from basic block BB. */
6541 gimple_purge_dead_abnormal_call_edges (basic_block bb)
6543 bool changed = gimple_purge_dead_eh_edges (bb);
6545 if (cfun->has_nonlocal_label)
6547 gimple stmt = last_stmt (bb);
6551 if (!(stmt && stmt_can_make_abnormal_goto (stmt)))
6552 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6554 if (e->flags & EDGE_ABNORMAL)
6563 /* See gimple_purge_dead_eh_edges below. */
6565 free_dominance_info (CDI_DOMINATORS);
6571 /* Stores all basic blocks dominated by BB to DOM_BBS. */
6574 get_all_dominated_blocks (basic_block bb, VEC (basic_block, heap) **dom_bbs)
6578 VEC_safe_push (basic_block, heap, *dom_bbs, bb);
6579 for (son = first_dom_son (CDI_DOMINATORS, bb);
6581 son = next_dom_son (CDI_DOMINATORS, son))
6582 get_all_dominated_blocks (son, dom_bbs);
6585 /* Removes edge E and all the blocks dominated by it, and updates dominance
6586 information. The IL in E->src needs to be updated separately.
6587 If dominance info is not available, only the edge E is removed.*/
6590 remove_edge_and_dominated_blocks (edge e)
6592 VEC (basic_block, heap) *bbs_to_remove = NULL;
6593 VEC (basic_block, heap) *bbs_to_fix_dom = NULL;
6597 bool none_removed = false;
6599 basic_block bb, dbb;
6602 if (!dom_info_available_p (CDI_DOMINATORS))
6608 /* No updating is needed for edges to exit. */
6609 if (e->dest == EXIT_BLOCK_PTR)
6611 if (cfgcleanup_altered_bbs)
6612 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6617 /* First, we find the basic blocks to remove. If E->dest has a predecessor
6618 that is not dominated by E->dest, then this set is empty. Otherwise,
6619 all the basic blocks dominated by E->dest are removed.
6621 Also, to DF_IDOM we store the immediate dominators of the blocks in
6622 the dominance frontier of E (i.e., of the successors of the
6623 removed blocks, if there are any, and of E->dest otherwise). */
6624 FOR_EACH_EDGE (f, ei, e->dest->preds)
6629 if (!dominated_by_p (CDI_DOMINATORS, f->src, e->dest))
6631 none_removed = true;
6636 df = BITMAP_ALLOC (NULL);
6637 df_idom = BITMAP_ALLOC (NULL);
6640 bitmap_set_bit (df_idom,
6641 get_immediate_dominator (CDI_DOMINATORS, e->dest)->index);
6644 get_all_dominated_blocks (e->dest, &bbs_to_remove);
6645 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6647 FOR_EACH_EDGE (f, ei, bb->succs)
6649 if (f->dest != EXIT_BLOCK_PTR)
6650 bitmap_set_bit (df, f->dest->index);
6653 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6654 bitmap_clear_bit (df, bb->index);
6656 EXECUTE_IF_SET_IN_BITMAP (df, 0, i, bi)
6658 bb = BASIC_BLOCK (i);
6659 bitmap_set_bit (df_idom,
6660 get_immediate_dominator (CDI_DOMINATORS, bb)->index);
6664 if (cfgcleanup_altered_bbs)
6666 /* Record the set of the altered basic blocks. */
6667 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6668 bitmap_ior_into (cfgcleanup_altered_bbs, df);
6671 /* Remove E and the cancelled blocks. */
6676 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6677 delete_basic_block (bb);
6680 /* Update the dominance information. The immediate dominator may change only
6681 for blocks whose immediate dominator belongs to DF_IDOM:
6683 Suppose that idom(X) = Y before removal of E and idom(X) != Y after the
6684 removal. Let Z the arbitrary block such that idom(Z) = Y and
6685 Z dominates X after the removal. Before removal, there exists a path P
6686 from Y to X that avoids Z. Let F be the last edge on P that is
6687 removed, and let W = F->dest. Before removal, idom(W) = Y (since Y
6688 dominates W, and because of P, Z does not dominate W), and W belongs to
6689 the dominance frontier of E. Therefore, Y belongs to DF_IDOM. */
6690 EXECUTE_IF_SET_IN_BITMAP (df_idom, 0, i, bi)
6692 bb = BASIC_BLOCK (i);
6693 for (dbb = first_dom_son (CDI_DOMINATORS, bb);
6695 dbb = next_dom_son (CDI_DOMINATORS, dbb))
6696 VEC_safe_push (basic_block, heap, bbs_to_fix_dom, dbb);
6699 iterate_fix_dominators (CDI_DOMINATORS, bbs_to_fix_dom, true);
6702 BITMAP_FREE (df_idom);
6703 VEC_free (basic_block, heap, bbs_to_remove);
6704 VEC_free (basic_block, heap, bbs_to_fix_dom);
6707 /* Purge dead EH edges from basic block BB. */
6710 gimple_purge_dead_eh_edges (basic_block bb)
6712 bool changed = false;
6715 gimple stmt = last_stmt (bb);
6717 if (stmt && stmt_can_throw_internal (stmt))
6720 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6722 if (e->flags & EDGE_EH)
6724 remove_edge_and_dominated_blocks (e);
6735 gimple_purge_all_dead_eh_edges (const_bitmap blocks)
6737 bool changed = false;
6741 EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
6743 basic_block bb = BASIC_BLOCK (i);
6745 /* Earlier gimple_purge_dead_eh_edges could have removed
6746 this basic block already. */
6747 gcc_assert (bb || changed);
6749 changed |= gimple_purge_dead_eh_edges (bb);
6755 /* This function is called whenever a new edge is created or
6759 gimple_execute_on_growing_pred (edge e)
6761 basic_block bb = e->dest;
6764 reserve_phi_args_for_new_edge (bb);
6767 /* This function is called immediately before edge E is removed from
6768 the edge vector E->dest->preds. */
6771 gimple_execute_on_shrinking_pred (edge e)
6773 if (phi_nodes (e->dest))
6774 remove_phi_args (e);
6777 /*---------------------------------------------------------------------------
6778 Helper functions for Loop versioning
6779 ---------------------------------------------------------------------------*/
6781 /* Adjust phi nodes for 'first' basic block. 'second' basic block is a copy
6782 of 'first'. Both of them are dominated by 'new_head' basic block. When
6783 'new_head' was created by 'second's incoming edge it received phi arguments
6784 on the edge by split_edge(). Later, additional edge 'e' was created to
6785 connect 'new_head' and 'first'. Now this routine adds phi args on this
6786 additional edge 'e' that new_head to second edge received as part of edge
6790 gimple_lv_adjust_loop_header_phi (basic_block first, basic_block second,
6791 basic_block new_head, edge e)
6794 gimple_stmt_iterator psi1, psi2;
6796 edge e2 = find_edge (new_head, second);
6798 /* Because NEW_HEAD has been created by splitting SECOND's incoming
6799 edge, we should always have an edge from NEW_HEAD to SECOND. */
6800 gcc_assert (e2 != NULL);
6802 /* Browse all 'second' basic block phi nodes and add phi args to
6803 edge 'e' for 'first' head. PHI args are always in correct order. */
6805 for (psi2 = gsi_start_phis (second),
6806 psi1 = gsi_start_phis (first);
6807 !gsi_end_p (psi2) && !gsi_end_p (psi1);
6808 gsi_next (&psi2), gsi_next (&psi1))
6810 phi1 = gsi_stmt (psi1);
6811 phi2 = gsi_stmt (psi2);
6812 def = PHI_ARG_DEF (phi2, e2->dest_idx);
6813 add_phi_arg (phi1, def, e);
6818 /* Adds a if else statement to COND_BB with condition COND_EXPR.
6819 SECOND_HEAD is the destination of the THEN and FIRST_HEAD is
6820 the destination of the ELSE part. */
6823 gimple_lv_add_condition_to_bb (basic_block first_head ATTRIBUTE_UNUSED,
6824 basic_block second_head ATTRIBUTE_UNUSED,
6825 basic_block cond_bb, void *cond_e)
6827 gimple_stmt_iterator gsi;
6828 gimple new_cond_expr;
6829 tree cond_expr = (tree) cond_e;
6832 /* Build new conditional expr */
6833 new_cond_expr = gimple_build_cond_from_tree (cond_expr,
6834 NULL_TREE, NULL_TREE);
6836 /* Add new cond in cond_bb. */
6837 gsi = gsi_last_bb (cond_bb);
6838 gsi_insert_after (&gsi, new_cond_expr, GSI_NEW_STMT);
6840 /* Adjust edges appropriately to connect new head with first head
6841 as well as second head. */
6842 e0 = single_succ_edge (cond_bb);
6843 e0->flags &= ~EDGE_FALLTHRU;
6844 e0->flags |= EDGE_FALSE_VALUE;
6847 struct cfg_hooks gimple_cfg_hooks = {
6849 gimple_verify_flow_info,
6850 gimple_dump_bb, /* dump_bb */
6851 create_bb, /* create_basic_block */
6852 gimple_redirect_edge_and_branch, /* redirect_edge_and_branch */
6853 gimple_redirect_edge_and_branch_force, /* redirect_edge_and_branch_force */
6854 gimple_can_remove_branch_p, /* can_remove_branch_p */
6855 remove_bb, /* delete_basic_block */
6856 gimple_split_block, /* split_block */
6857 gimple_move_block_after, /* move_block_after */
6858 gimple_can_merge_blocks_p, /* can_merge_blocks_p */
6859 gimple_merge_blocks, /* merge_blocks */
6860 gimple_predict_edge, /* predict_edge */
6861 gimple_predicted_by_p, /* predicted_by_p */
6862 gimple_can_duplicate_bb_p, /* can_duplicate_block_p */
6863 gimple_duplicate_bb, /* duplicate_block */
6864 gimple_split_edge, /* split_edge */
6865 gimple_make_forwarder_block, /* make_forward_block */
6866 NULL, /* tidy_fallthru_edge */
6867 gimple_block_ends_with_call_p,/* block_ends_with_call_p */
6868 gimple_block_ends_with_condjump_p, /* block_ends_with_condjump_p */
6869 gimple_flow_call_edges_add, /* flow_call_edges_add */
6870 gimple_execute_on_growing_pred, /* execute_on_growing_pred */
6871 gimple_execute_on_shrinking_pred, /* execute_on_shrinking_pred */
6872 gimple_duplicate_loop_to_header_edge, /* duplicate loop for trees */
6873 gimple_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
6874 gimple_lv_adjust_loop_header_phi, /* lv_adjust_loop_header_phi*/
6875 extract_true_false_edges_from_block, /* extract_cond_bb_edges */
6876 flush_pending_stmts /* flush_pending_stmts */
6880 /* Split all critical edges. */
6883 split_critical_edges (void)
6889 /* split_edge can redirect edges out of SWITCH_EXPRs, which can get
6890 expensive. So we want to enable recording of edge to CASE_LABEL_EXPR
6891 mappings around the calls to split_edge. */
6892 start_recording_case_labels ();
6895 FOR_EACH_EDGE (e, ei, bb->succs)
6896 if (EDGE_CRITICAL_P (e) && !(e->flags & EDGE_ABNORMAL))
6901 end_recording_case_labels ();
6905 struct gimple_opt_pass pass_split_crit_edges =
6909 "crited", /* name */
6911 split_critical_edges, /* execute */
6914 0, /* static_pass_number */
6915 TV_TREE_SPLIT_EDGES, /* tv_id */
6916 PROP_cfg, /* properties required */
6917 PROP_no_crit_edges, /* properties_provided */
6918 0, /* properties_destroyed */
6919 0, /* todo_flags_start */
6920 TODO_dump_func /* todo_flags_finish */
6925 /* Build a ternary operation and gimplify it. Emit code before GSI.
6926 Return the gimple_val holding the result. */
6929 gimplify_build3 (gimple_stmt_iterator *gsi, enum tree_code code,
6930 tree type, tree a, tree b, tree c)
6934 ret = fold_build3 (code, type, a, b, c);
6937 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
6941 /* Build a binary operation and gimplify it. Emit code before GSI.
6942 Return the gimple_val holding the result. */
6945 gimplify_build2 (gimple_stmt_iterator *gsi, enum tree_code code,
6946 tree type, tree a, tree b)
6950 ret = fold_build2 (code, type, a, b);
6953 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
6957 /* Build a unary operation and gimplify it. Emit code before GSI.
6958 Return the gimple_val holding the result. */
6961 gimplify_build1 (gimple_stmt_iterator *gsi, enum tree_code code, tree type,
6966 ret = fold_build1 (code, type, a);
6969 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
6975 /* Emit return warnings. */
6978 execute_warn_function_return (void)
6980 source_location location;
6985 /* If we have a path to EXIT, then we do return. */
6986 if (TREE_THIS_VOLATILE (cfun->decl)
6987 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0)
6989 location = UNKNOWN_LOCATION;
6990 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
6992 last = last_stmt (e->src);
6993 if (gimple_code (last) == GIMPLE_RETURN
6994 && (location = gimple_location (last)) != UNKNOWN_LOCATION)
6997 if (location == UNKNOWN_LOCATION)
6998 location = cfun->function_end_locus;
6999 warning (0, "%H%<noreturn%> function does return", &location);
7002 /* If we see "return;" in some basic block, then we do reach the end
7003 without returning a value. */
7004 else if (warn_return_type
7005 && !TREE_NO_WARNING (cfun->decl)
7006 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0
7007 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (cfun->decl))))
7009 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7011 gimple last = last_stmt (e->src);
7012 if (gimple_code (last) == GIMPLE_RETURN
7013 && gimple_return_retval (last) == NULL
7014 && !gimple_no_warning_p (last))
7016 location = gimple_location (last);
7017 if (location == UNKNOWN_LOCATION)
7018 location = cfun->function_end_locus;
7019 warning_at (location, OPT_Wreturn_type, "control reaches end of non-void function");
7020 TREE_NO_WARNING (cfun->decl) = 1;
7029 /* Given a basic block B which ends with a conditional and has
7030 precisely two successors, determine which of the edges is taken if
7031 the conditional is true and which is taken if the conditional is
7032 false. Set TRUE_EDGE and FALSE_EDGE appropriately. */
7035 extract_true_false_edges_from_block (basic_block b,
7039 edge e = EDGE_SUCC (b, 0);
7041 if (e->flags & EDGE_TRUE_VALUE)
7044 *false_edge = EDGE_SUCC (b, 1);
7049 *true_edge = EDGE_SUCC (b, 1);
7053 struct gimple_opt_pass pass_warn_function_return =
7059 execute_warn_function_return, /* execute */
7062 0, /* static_pass_number */
7064 PROP_cfg, /* properties_required */
7065 0, /* properties_provided */
7066 0, /* properties_destroyed */
7067 0, /* todo_flags_start */
7068 0 /* todo_flags_finish */
7072 /* Emit noreturn warnings. */
7075 execute_warn_function_noreturn (void)
7077 if (warn_missing_noreturn
7078 && !TREE_THIS_VOLATILE (cfun->decl)
7079 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0
7080 && !lang_hooks.missing_noreturn_ok_p (cfun->decl))
7081 warning (OPT_Wmissing_noreturn, "%Jfunction might be possible candidate "
7082 "for attribute %<noreturn%>",
7087 struct gimple_opt_pass pass_warn_function_noreturn =
7093 execute_warn_function_noreturn, /* execute */
7096 0, /* static_pass_number */
7098 PROP_cfg, /* properties_required */
7099 0, /* properties_provided */
7100 0, /* properties_destroyed */
7101 0, /* todo_flags_start */
7102 0 /* todo_flags_finish */