1 /* Control flow functions for trees.
2 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
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);
224 if (dump_file && (dump_flags & TDF_DETAILS))
226 fprintf (dump_file, "Scope blocks:\n");
227 dump_scope_blocks (dump_file, dump_flags);
232 struct gimple_opt_pass pass_build_cfg =
238 execute_build_cfg, /* execute */
241 0, /* static_pass_number */
242 TV_TREE_CFG, /* tv_id */
243 PROP_gimple_leh, /* properties_required */
244 PROP_cfg, /* properties_provided */
245 0, /* properties_destroyed */
246 0, /* todo_flags_start */
247 TODO_verify_stmts | TODO_cleanup_cfg
248 | TODO_dump_func /* todo_flags_finish */
253 /* Return true if T is a computed goto. */
256 computed_goto_p (gimple t)
258 return (gimple_code (t) == GIMPLE_GOTO
259 && TREE_CODE (gimple_goto_dest (t)) != LABEL_DECL);
263 /* Search the CFG for any computed gotos. If found, factor them to a
264 common computed goto site. Also record the location of that site so
265 that we can un-factor the gotos after we have converted back to
269 factor_computed_gotos (void)
272 tree factored_label_decl = NULL;
274 gimple factored_computed_goto_label = NULL;
275 gimple factored_computed_goto = NULL;
277 /* We know there are one or more computed gotos in this function.
278 Examine the last statement in each basic block to see if the block
279 ends with a computed goto. */
283 gimple_stmt_iterator gsi = gsi_last_bb (bb);
289 last = gsi_stmt (gsi);
291 /* Ignore the computed goto we create when we factor the original
293 if (last == factored_computed_goto)
296 /* If the last statement is a computed goto, factor it. */
297 if (computed_goto_p (last))
301 /* The first time we find a computed goto we need to create
302 the factored goto block and the variable each original
303 computed goto will use for their goto destination. */
304 if (!factored_computed_goto)
306 basic_block new_bb = create_empty_bb (bb);
307 gimple_stmt_iterator new_gsi = gsi_start_bb (new_bb);
309 /* Create the destination of the factored goto. Each original
310 computed goto will put its desired destination into this
311 variable and jump to the label we create immediately
313 var = create_tmp_var (ptr_type_node, "gotovar");
315 /* Build a label for the new block which will contain the
316 factored computed goto. */
317 factored_label_decl = create_artificial_label ();
318 factored_computed_goto_label
319 = gimple_build_label (factored_label_decl);
320 gsi_insert_after (&new_gsi, factored_computed_goto_label,
323 /* Build our new computed goto. */
324 factored_computed_goto = gimple_build_goto (var);
325 gsi_insert_after (&new_gsi, factored_computed_goto, GSI_NEW_STMT);
328 /* Copy the original computed goto's destination into VAR. */
329 assignment = gimple_build_assign (var, gimple_goto_dest (last));
330 gsi_insert_before (&gsi, assignment, GSI_SAME_STMT);
332 /* And re-vector the computed goto to the new destination. */
333 gimple_goto_set_dest (last, factored_label_decl);
339 /* Build a flowgraph for the sequence of stmts SEQ. */
342 make_blocks (gimple_seq seq)
344 gimple_stmt_iterator i = gsi_start (seq);
346 bool start_new_block = true;
347 bool first_stmt_of_seq = true;
348 basic_block bb = ENTRY_BLOCK_PTR;
350 while (!gsi_end_p (i))
357 /* If the statement starts a new basic block or if we have determined
358 in a previous pass that we need to create a new block for STMT, do
360 if (start_new_block || stmt_starts_bb_p (stmt, prev_stmt))
362 if (!first_stmt_of_seq)
363 seq = gsi_split_seq_before (&i);
364 bb = create_basic_block (seq, NULL, bb);
365 start_new_block = false;
368 /* Now add STMT to BB and create the subgraphs for special statement
370 gimple_set_bb (stmt, bb);
372 if (computed_goto_p (stmt))
373 found_computed_goto = true;
375 /* If STMT is a basic block terminator, set START_NEW_BLOCK for the
377 if (stmt_ends_bb_p (stmt))
379 /* If the stmt can make abnormal goto use a new temporary
380 for the assignment to the LHS. This makes sure the old value
381 of the LHS is available on the abnormal edge. Otherwise
382 we will end up with overlapping life-ranges for abnormal
384 if (gimple_has_lhs (stmt)
385 && stmt_can_make_abnormal_goto (stmt)
386 && is_gimple_reg_type (TREE_TYPE (gimple_get_lhs (stmt))))
388 tree lhs = gimple_get_lhs (stmt);
389 tree tmp = create_tmp_var (TREE_TYPE (lhs), NULL);
390 gimple s = gimple_build_assign (lhs, tmp);
391 gimple_set_location (s, gimple_location (stmt));
392 gimple_set_block (s, gimple_block (stmt));
393 gimple_set_lhs (stmt, tmp);
394 if (TREE_CODE (TREE_TYPE (tmp)) == COMPLEX_TYPE
395 || TREE_CODE (TREE_TYPE (tmp)) == VECTOR_TYPE)
396 DECL_GIMPLE_REG_P (tmp) = 1;
397 gsi_insert_after (&i, s, GSI_SAME_STMT);
399 start_new_block = true;
403 first_stmt_of_seq = false;
408 /* Create and return a new empty basic block after bb AFTER. */
411 create_bb (void *h, void *e, basic_block after)
417 /* Create and initialize a new basic block. Since alloc_block uses
418 ggc_alloc_cleared to allocate a basic block, we do not have to
419 clear the newly allocated basic block here. */
422 bb->index = last_basic_block;
424 bb->il.gimple = GGC_CNEW (struct gimple_bb_info);
425 set_bb_seq (bb, h ? (gimple_seq) h : gimple_seq_alloc ());
427 /* Add the new block to the linked list of blocks. */
428 link_block (bb, after);
430 /* Grow the basic block array if needed. */
431 if ((size_t) last_basic_block == VEC_length (basic_block, basic_block_info))
433 size_t new_size = last_basic_block + (last_basic_block + 3) / 4;
434 VEC_safe_grow_cleared (basic_block, gc, basic_block_info, new_size);
437 /* Add the newly created block to the array. */
438 SET_BASIC_BLOCK (last_basic_block, bb);
447 /*---------------------------------------------------------------------------
449 ---------------------------------------------------------------------------*/
451 /* Fold COND_EXPR_COND of each COND_EXPR. */
454 fold_cond_expr_cond (void)
460 gimple stmt = last_stmt (bb);
462 if (stmt && gimple_code (stmt) == GIMPLE_COND)
467 fold_defer_overflow_warnings ();
468 cond = fold_binary (gimple_cond_code (stmt), boolean_type_node,
469 gimple_cond_lhs (stmt), gimple_cond_rhs (stmt));
472 zerop = integer_zerop (cond);
473 onep = integer_onep (cond);
476 zerop = onep = false;
478 fold_undefer_overflow_warnings (zerop || onep,
480 WARN_STRICT_OVERFLOW_CONDITIONAL);
482 gimple_cond_make_false (stmt);
484 gimple_cond_make_true (stmt);
489 /* Join all the blocks in the flowgraph. */
495 struct omp_region *cur_region = NULL;
497 /* Create an edge from entry to the first block with executable
499 make_edge (ENTRY_BLOCK_PTR, BASIC_BLOCK (NUM_FIXED_BLOCKS), EDGE_FALLTHRU);
501 /* Traverse the basic block array placing edges. */
504 gimple last = last_stmt (bb);
509 enum gimple_code code = gimple_code (last);
513 make_goto_expr_edges (bb);
517 make_edge (bb, EXIT_BLOCK_PTR, 0);
521 make_cond_expr_edges (bb);
525 make_gimple_switch_edges (bb);
529 make_eh_edges (last);
534 /* If this function receives a nonlocal goto, then we need to
535 make edges from this call site to all the nonlocal goto
537 if (stmt_can_make_abnormal_goto (last))
538 make_abnormal_goto_edges (bb, true);
540 /* If this statement has reachable exception handlers, then
541 create abnormal edges to them. */
542 make_eh_edges (last);
544 /* Some calls are known not to return. */
545 fallthru = !(gimple_call_flags (last) & ECF_NORETURN);
549 /* A GIMPLE_ASSIGN may throw internally and thus be considered
551 if (is_ctrl_altering_stmt (last))
553 make_eh_edges (last);
558 case GIMPLE_OMP_PARALLEL:
559 case GIMPLE_OMP_TASK:
561 case GIMPLE_OMP_SINGLE:
562 case GIMPLE_OMP_MASTER:
563 case GIMPLE_OMP_ORDERED:
564 case GIMPLE_OMP_CRITICAL:
565 case GIMPLE_OMP_SECTION:
566 cur_region = new_omp_region (bb, code, cur_region);
570 case GIMPLE_OMP_SECTIONS:
571 cur_region = new_omp_region (bb, code, cur_region);
575 case GIMPLE_OMP_SECTIONS_SWITCH:
580 case GIMPLE_OMP_ATOMIC_LOAD:
581 case GIMPLE_OMP_ATOMIC_STORE:
586 case GIMPLE_OMP_RETURN:
587 /* In the case of a GIMPLE_OMP_SECTION, the edge will go
588 somewhere other than the next block. This will be
590 cur_region->exit = bb;
591 fallthru = cur_region->type != GIMPLE_OMP_SECTION;
592 cur_region = cur_region->outer;
595 case GIMPLE_OMP_CONTINUE:
596 cur_region->cont = bb;
597 switch (cur_region->type)
600 /* Mark all GIMPLE_OMP_FOR and GIMPLE_OMP_CONTINUE
601 succs edges as abnormal to prevent splitting
603 single_succ_edge (cur_region->entry)->flags |= EDGE_ABNORMAL;
604 /* Make the loopback edge. */
605 make_edge (bb, single_succ (cur_region->entry),
608 /* Create an edge from GIMPLE_OMP_FOR to exit, which
609 corresponds to the case that the body of the loop
610 is not executed at all. */
611 make_edge (cur_region->entry, bb->next_bb, EDGE_ABNORMAL);
612 make_edge (bb, bb->next_bb, EDGE_FALLTHRU | EDGE_ABNORMAL);
616 case GIMPLE_OMP_SECTIONS:
617 /* Wire up the edges into and out of the nested sections. */
619 basic_block switch_bb = single_succ (cur_region->entry);
621 struct omp_region *i;
622 for (i = cur_region->inner; i ; i = i->next)
624 gcc_assert (i->type == GIMPLE_OMP_SECTION);
625 make_edge (switch_bb, i->entry, 0);
626 make_edge (i->exit, bb, EDGE_FALLTHRU);
629 /* Make the loopback edge to the block with
630 GIMPLE_OMP_SECTIONS_SWITCH. */
631 make_edge (bb, switch_bb, 0);
633 /* Make the edge from the switch to exit. */
634 make_edge (switch_bb, bb->next_bb, 0);
645 gcc_assert (!stmt_ends_bb_p (last));
653 make_edge (bb, bb->next_bb, EDGE_FALLTHRU);
659 /* Fold COND_EXPR_COND of each COND_EXPR. */
660 fold_cond_expr_cond ();
664 /* Create the edges for a GIMPLE_COND starting at block BB. */
667 make_cond_expr_edges (basic_block bb)
669 gimple entry = last_stmt (bb);
670 gimple then_stmt, else_stmt;
671 basic_block then_bb, else_bb;
672 tree then_label, else_label;
676 gcc_assert (gimple_code (entry) == GIMPLE_COND);
678 /* Entry basic blocks for each component. */
679 then_label = gimple_cond_true_label (entry);
680 else_label = gimple_cond_false_label (entry);
681 then_bb = label_to_block (then_label);
682 else_bb = label_to_block (else_label);
683 then_stmt = first_stmt (then_bb);
684 else_stmt = first_stmt (else_bb);
686 e = make_edge (bb, then_bb, EDGE_TRUE_VALUE);
687 e->goto_locus = gimple_location (then_stmt);
689 e->goto_block = gimple_block (then_stmt);
690 e = make_edge (bb, else_bb, EDGE_FALSE_VALUE);
693 e->goto_locus = gimple_location (else_stmt);
695 e->goto_block = gimple_block (else_stmt);
698 /* We do not need the labels anymore. */
699 gimple_cond_set_true_label (entry, NULL_TREE);
700 gimple_cond_set_false_label (entry, NULL_TREE);
704 /* Called for each element in the hash table (P) as we delete the
705 edge to cases hash table.
707 Clear all the TREE_CHAINs to prevent problems with copying of
708 SWITCH_EXPRs and structure sharing rules, then free the hash table
712 edge_to_cases_cleanup (const void *key ATTRIBUTE_UNUSED, void **value,
713 void *data ATTRIBUTE_UNUSED)
717 for (t = (tree) *value; t; t = next)
719 next = TREE_CHAIN (t);
720 TREE_CHAIN (t) = NULL;
727 /* Start recording information mapping edges to case labels. */
730 start_recording_case_labels (void)
732 gcc_assert (edge_to_cases == NULL);
733 edge_to_cases = pointer_map_create ();
736 /* Return nonzero if we are recording information for case labels. */
739 recording_case_labels_p (void)
741 return (edge_to_cases != NULL);
744 /* Stop recording information mapping edges to case labels and
745 remove any information we have recorded. */
747 end_recording_case_labels (void)
749 pointer_map_traverse (edge_to_cases, edge_to_cases_cleanup, NULL);
750 pointer_map_destroy (edge_to_cases);
751 edge_to_cases = NULL;
754 /* If we are inside a {start,end}_recording_cases block, then return
755 a chain of CASE_LABEL_EXPRs from T which reference E.
757 Otherwise return NULL. */
760 get_cases_for_edge (edge e, gimple t)
765 /* If we are not recording cases, then we do not have CASE_LABEL_EXPR
766 chains available. Return NULL so the caller can detect this case. */
767 if (!recording_case_labels_p ())
770 slot = pointer_map_contains (edge_to_cases, e);
774 /* If we did not find E in the hash table, then this must be the first
775 time we have been queried for information about E & T. Add all the
776 elements from T to the hash table then perform the query again. */
778 n = gimple_switch_num_labels (t);
779 for (i = 0; i < n; i++)
781 tree elt = gimple_switch_label (t, i);
782 tree lab = CASE_LABEL (elt);
783 basic_block label_bb = label_to_block (lab);
784 edge this_edge = find_edge (e->src, label_bb);
786 /* Add it to the chain of CASE_LABEL_EXPRs referencing E, or create
788 slot = pointer_map_insert (edge_to_cases, this_edge);
789 TREE_CHAIN (elt) = (tree) *slot;
793 return (tree) *pointer_map_contains (edge_to_cases, e);
796 /* Create the edges for a GIMPLE_SWITCH starting at block BB. */
799 make_gimple_switch_edges (basic_block bb)
801 gimple entry = last_stmt (bb);
804 n = gimple_switch_num_labels (entry);
806 for (i = 0; i < n; ++i)
808 tree lab = CASE_LABEL (gimple_switch_label (entry, i));
809 basic_block label_bb = label_to_block (lab);
810 make_edge (bb, label_bb, 0);
815 /* Return the basic block holding label DEST. */
818 label_to_block_fn (struct function *ifun, tree dest)
820 int uid = LABEL_DECL_UID (dest);
822 /* We would die hard when faced by an undefined label. Emit a label to
823 the very first basic block. This will hopefully make even the dataflow
824 and undefined variable warnings quite right. */
825 if ((errorcount || sorrycount) && uid < 0)
827 gimple_stmt_iterator gsi = gsi_start_bb (BASIC_BLOCK (NUM_FIXED_BLOCKS));
830 stmt = gimple_build_label (dest);
831 gsi_insert_before (&gsi, stmt, GSI_NEW_STMT);
832 uid = LABEL_DECL_UID (dest);
834 if (VEC_length (basic_block, ifun->cfg->x_label_to_block_map)
835 <= (unsigned int) uid)
837 return VEC_index (basic_block, ifun->cfg->x_label_to_block_map, uid);
840 /* Create edges for an abnormal goto statement at block BB. If FOR_CALL
841 is true, the source statement is a CALL_EXPR instead of a GOTO_EXPR. */
844 make_abnormal_goto_edges (basic_block bb, bool for_call)
846 basic_block target_bb;
847 gimple_stmt_iterator gsi;
849 FOR_EACH_BB (target_bb)
850 for (gsi = gsi_start_bb (target_bb); !gsi_end_p (gsi); gsi_next (&gsi))
852 gimple label_stmt = gsi_stmt (gsi);
855 if (gimple_code (label_stmt) != GIMPLE_LABEL)
858 target = gimple_label_label (label_stmt);
860 /* Make an edge to every label block that has been marked as a
861 potential target for a computed goto or a non-local goto. */
862 if ((FORCED_LABEL (target) && !for_call)
863 || (DECL_NONLOCAL (target) && for_call))
865 make_edge (bb, target_bb, EDGE_ABNORMAL);
871 /* Create edges for a goto statement at block BB. */
874 make_goto_expr_edges (basic_block bb)
876 gimple_stmt_iterator last = gsi_last_bb (bb);
877 gimple goto_t = gsi_stmt (last);
879 /* A simple GOTO creates normal edges. */
880 if (simple_goto_p (goto_t))
882 tree dest = gimple_goto_dest (goto_t);
883 edge e = make_edge (bb, label_to_block (dest), EDGE_FALLTHRU);
884 e->goto_locus = gimple_location (goto_t);
886 e->goto_block = gimple_block (goto_t);
887 gsi_remove (&last, true);
891 /* A computed GOTO creates abnormal edges. */
892 make_abnormal_goto_edges (bb, false);
896 /*---------------------------------------------------------------------------
898 ---------------------------------------------------------------------------*/
900 /* Cleanup useless labels in basic blocks. This is something we wish
901 to do early because it allows us to group case labels before creating
902 the edges for the CFG, and it speeds up block statement iterators in
904 We rerun this pass after CFG is created, to get rid of the labels that
905 are no longer referenced. After then we do not run it any more, since
906 (almost) no new labels should be created. */
908 /* A map from basic block index to the leading label of that block. */
909 static struct label_record
914 /* True if the label is referenced from somewhere. */
918 /* Callback for for_each_eh_region. Helper for cleanup_dead_labels. */
920 update_eh_label (struct eh_region *region)
922 tree old_label = get_eh_region_tree_label (region);
926 basic_block bb = label_to_block (old_label);
928 /* ??? After optimizing, there may be EH regions with labels
929 that have already been removed from the function body, so
930 there is no basic block for them. */
934 new_label = label_for_bb[bb->index].label;
935 label_for_bb[bb->index].used = true;
936 set_eh_region_tree_label (region, new_label);
941 /* Given LABEL return the first label in the same basic block. */
944 main_block_label (tree label)
946 basic_block bb = label_to_block (label);
947 tree main_label = label_for_bb[bb->index].label;
949 /* label_to_block possibly inserted undefined label into the chain. */
952 label_for_bb[bb->index].label = label;
956 label_for_bb[bb->index].used = true;
960 /* Cleanup redundant labels. This is a three-step process:
961 1) Find the leading label for each block.
962 2) Redirect all references to labels to the leading labels.
963 3) Cleanup all useless labels. */
966 cleanup_dead_labels (void)
969 label_for_bb = XCNEWVEC (struct label_record, last_basic_block);
971 /* Find a suitable label for each block. We use the first user-defined
972 label if there is one, or otherwise just the first label we see. */
975 gimple_stmt_iterator i;
977 for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
980 gimple stmt = gsi_stmt (i);
982 if (gimple_code (stmt) != GIMPLE_LABEL)
985 label = gimple_label_label (stmt);
987 /* If we have not yet seen a label for the current block,
988 remember this one and see if there are more labels. */
989 if (!label_for_bb[bb->index].label)
991 label_for_bb[bb->index].label = label;
995 /* If we did see a label for the current block already, but it
996 is an artificially created label, replace it if the current
997 label is a user defined label. */
998 if (!DECL_ARTIFICIAL (label)
999 && DECL_ARTIFICIAL (label_for_bb[bb->index].label))
1001 label_for_bb[bb->index].label = label;
1007 /* Now redirect all jumps/branches to the selected label.
1008 First do so for each block ending in a control statement. */
1011 gimple stmt = last_stmt (bb);
1015 switch (gimple_code (stmt))
1019 tree true_label = gimple_cond_true_label (stmt);
1020 tree false_label = gimple_cond_false_label (stmt);
1023 gimple_cond_set_true_label (stmt, main_block_label (true_label));
1025 gimple_cond_set_false_label (stmt, main_block_label (false_label));
1031 size_t i, n = gimple_switch_num_labels (stmt);
1033 /* Replace all destination labels. */
1034 for (i = 0; i < n; ++i)
1036 tree case_label = gimple_switch_label (stmt, i);
1037 tree label = main_block_label (CASE_LABEL (case_label));
1038 CASE_LABEL (case_label) = label;
1043 /* We have to handle gotos until they're removed, and we don't
1044 remove them until after we've created the CFG edges. */
1046 if (!computed_goto_p (stmt))
1048 tree new_dest = main_block_label (gimple_goto_dest (stmt));
1049 gimple_goto_set_dest (stmt, new_dest);
1058 for_each_eh_region (update_eh_label);
1060 /* Finally, purge dead labels. All user-defined labels and labels that
1061 can be the target of non-local gotos and labels which have their
1062 address taken are preserved. */
1065 gimple_stmt_iterator i;
1066 tree label_for_this_bb = label_for_bb[bb->index].label;
1068 if (!label_for_this_bb)
1071 /* If the main label of the block is unused, we may still remove it. */
1072 if (!label_for_bb[bb->index].used)
1073 label_for_this_bb = NULL;
1075 for (i = gsi_start_bb (bb); !gsi_end_p (i); )
1078 gimple stmt = gsi_stmt (i);
1080 if (gimple_code (stmt) != GIMPLE_LABEL)
1083 label = gimple_label_label (stmt);
1085 if (label == label_for_this_bb
1086 || !DECL_ARTIFICIAL (label)
1087 || DECL_NONLOCAL (label)
1088 || FORCED_LABEL (label))
1091 gsi_remove (&i, true);
1095 free (label_for_bb);
1098 /* Look for blocks ending in a multiway branch (a SWITCH_EXPR in GIMPLE),
1099 and scan the sorted vector of cases. Combine the ones jumping to the
1101 Eg. three separate entries 1: 2: 3: become one entry 1..3: */
1104 group_case_labels (void)
1110 gimple stmt = last_stmt (bb);
1111 if (stmt && gimple_code (stmt) == GIMPLE_SWITCH)
1113 int old_size = gimple_switch_num_labels (stmt);
1114 int i, j, new_size = old_size;
1115 tree default_case = NULL_TREE;
1116 tree default_label = NULL_TREE;
1119 /* The default label is always the first case in a switch
1120 statement after gimplification if it was not optimized
1122 if (!CASE_LOW (gimple_switch_default_label (stmt))
1123 && !CASE_HIGH (gimple_switch_default_label (stmt)))
1125 default_case = gimple_switch_default_label (stmt);
1126 default_label = CASE_LABEL (default_case);
1130 has_default = false;
1132 /* Look for possible opportunities to merge cases. */
1137 while (i < old_size)
1139 tree base_case, base_label, base_high;
1140 base_case = gimple_switch_label (stmt, i);
1142 gcc_assert (base_case);
1143 base_label = CASE_LABEL (base_case);
1145 /* Discard cases that have the same destination as the
1147 if (base_label == default_label)
1149 gimple_switch_set_label (stmt, i, NULL_TREE);
1155 base_high = CASE_HIGH (base_case)
1156 ? CASE_HIGH (base_case)
1157 : CASE_LOW (base_case);
1160 /* Try to merge case labels. Break out when we reach the end
1161 of the label vector or when we cannot merge the next case
1162 label with the current one. */
1163 while (i < old_size)
1165 tree merge_case = gimple_switch_label (stmt, i);
1166 tree merge_label = CASE_LABEL (merge_case);
1167 tree t = int_const_binop (PLUS_EXPR, base_high,
1168 integer_one_node, 1);
1170 /* Merge the cases if they jump to the same place,
1171 and their ranges are consecutive. */
1172 if (merge_label == base_label
1173 && tree_int_cst_equal (CASE_LOW (merge_case), t))
1175 base_high = CASE_HIGH (merge_case) ?
1176 CASE_HIGH (merge_case) : CASE_LOW (merge_case);
1177 CASE_HIGH (base_case) = base_high;
1178 gimple_switch_set_label (stmt, i, NULL_TREE);
1187 /* Compress the case labels in the label vector, and adjust the
1188 length of the vector. */
1189 for (i = 0, j = 0; i < new_size; i++)
1191 while (! gimple_switch_label (stmt, j))
1193 gimple_switch_set_label (stmt, i,
1194 gimple_switch_label (stmt, j++));
1197 gcc_assert (new_size <= old_size);
1198 gimple_switch_set_num_labels (stmt, new_size);
1203 /* Checks whether we can merge block B into block A. */
1206 gimple_can_merge_blocks_p (basic_block a, basic_block b)
1209 gimple_stmt_iterator gsi;
1212 if (!single_succ_p (a))
1215 if (single_succ_edge (a)->flags & (EDGE_ABNORMAL | EDGE_EH))
1218 if (single_succ (a) != b)
1221 if (!single_pred_p (b))
1224 if (b == EXIT_BLOCK_PTR)
1227 /* If A ends by a statement causing exceptions or something similar, we
1228 cannot merge the blocks. */
1229 stmt = last_stmt (a);
1230 if (stmt && stmt_ends_bb_p (stmt))
1233 /* Do not allow a block with only a non-local label to be merged. */
1235 && gimple_code (stmt) == GIMPLE_LABEL
1236 && DECL_NONLOCAL (gimple_label_label (stmt)))
1239 /* It must be possible to eliminate all phi nodes in B. If ssa form
1240 is not up-to-date, we cannot eliminate any phis; however, if only
1241 some symbols as whole are marked for renaming, this is not a problem,
1242 as phi nodes for those symbols are irrelevant in updating anyway. */
1243 phis = phi_nodes (b);
1244 if (!gimple_seq_empty_p (phis))
1246 gimple_stmt_iterator i;
1248 if (name_mappings_registered_p ())
1251 for (i = gsi_start (phis); !gsi_end_p (i); gsi_next (&i))
1253 gimple phi = gsi_stmt (i);
1255 if (!is_gimple_reg (gimple_phi_result (phi))
1256 && !may_propagate_copy (gimple_phi_result (phi),
1257 gimple_phi_arg_def (phi, 0)))
1262 /* Do not remove user labels. */
1263 for (gsi = gsi_start_bb (b); !gsi_end_p (gsi); gsi_next (&gsi))
1265 stmt = gsi_stmt (gsi);
1266 if (gimple_code (stmt) != GIMPLE_LABEL)
1268 if (!DECL_ARTIFICIAL (gimple_label_label (stmt)))
1272 /* Protect the loop latches. */
1274 && b->loop_father->latch == b)
1280 /* Replaces all uses of NAME by VAL. */
1283 replace_uses_by (tree name, tree val)
1285 imm_use_iterator imm_iter;
1290 FOR_EACH_IMM_USE_STMT (stmt, imm_iter, name)
1292 if (gimple_code (stmt) != GIMPLE_PHI)
1293 push_stmt_changes (&stmt);
1295 FOR_EACH_IMM_USE_ON_STMT (use, imm_iter)
1297 replace_exp (use, val);
1299 if (gimple_code (stmt) == GIMPLE_PHI)
1301 e = gimple_phi_arg_edge (stmt, PHI_ARG_INDEX_FROM_USE (use));
1302 if (e->flags & EDGE_ABNORMAL)
1304 /* This can only occur for virtual operands, since
1305 for the real ones SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name))
1306 would prevent replacement. */
1307 gcc_assert (!is_gimple_reg (name));
1308 SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val) = 1;
1313 if (gimple_code (stmt) != GIMPLE_PHI)
1317 fold_stmt_inplace (stmt);
1318 if (cfgcleanup_altered_bbs)
1319 bitmap_set_bit (cfgcleanup_altered_bbs, gimple_bb (stmt)->index);
1321 /* FIXME. This should go in pop_stmt_changes. */
1322 for (i = 0; i < gimple_num_ops (stmt); i++)
1324 tree op = gimple_op (stmt, i);
1325 /* Operands may be empty here. For example, the labels
1326 of a GIMPLE_COND are nulled out following the creation
1327 of the corresponding CFG edges. */
1328 if (op && TREE_CODE (op) == ADDR_EXPR)
1329 recompute_tree_invariant_for_addr_expr (op);
1332 maybe_clean_or_replace_eh_stmt (stmt, stmt);
1334 pop_stmt_changes (&stmt);
1338 gcc_assert (has_zero_uses (name));
1340 /* Also update the trees stored in loop structures. */
1346 FOR_EACH_LOOP (li, loop, 0)
1348 substitute_in_loop_info (loop, name, val);
1353 /* Merge block B into block A. */
1356 gimple_merge_blocks (basic_block a, basic_block b)
1358 gimple_stmt_iterator last, gsi, psi;
1359 gimple_seq phis = phi_nodes (b);
1362 fprintf (dump_file, "Merging blocks %d and %d\n", a->index, b->index);
1364 /* Remove all single-valued PHI nodes from block B of the form
1365 V_i = PHI <V_j> by propagating V_j to all the uses of V_i. */
1366 gsi = gsi_last_bb (a);
1367 for (psi = gsi_start (phis); !gsi_end_p (psi); )
1369 gimple phi = gsi_stmt (psi);
1370 tree def = gimple_phi_result (phi), use = gimple_phi_arg_def (phi, 0);
1372 bool may_replace_uses = !is_gimple_reg (def)
1373 || may_propagate_copy (def, use);
1375 /* In case we maintain loop closed ssa form, do not propagate arguments
1376 of loop exit phi nodes. */
1378 && loops_state_satisfies_p (LOOP_CLOSED_SSA)
1379 && is_gimple_reg (def)
1380 && TREE_CODE (use) == SSA_NAME
1381 && a->loop_father != b->loop_father)
1382 may_replace_uses = false;
1384 if (!may_replace_uses)
1386 gcc_assert (is_gimple_reg (def));
1388 /* Note that just emitting the copies is fine -- there is no problem
1389 with ordering of phi nodes. This is because A is the single
1390 predecessor of B, therefore results of the phi nodes cannot
1391 appear as arguments of the phi nodes. */
1392 copy = gimple_build_assign (def, use);
1393 gsi_insert_after (&gsi, copy, GSI_NEW_STMT);
1394 remove_phi_node (&psi, false);
1398 /* If we deal with a PHI for virtual operands, we can simply
1399 propagate these without fussing with folding or updating
1401 if (!is_gimple_reg (def))
1403 imm_use_iterator iter;
1404 use_operand_p use_p;
1407 FOR_EACH_IMM_USE_STMT (stmt, iter, def)
1408 FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
1409 SET_USE (use_p, use);
1412 replace_uses_by (def, use);
1414 remove_phi_node (&psi, true);
1418 /* Ensure that B follows A. */
1419 move_block_after (b, a);
1421 gcc_assert (single_succ_edge (a)->flags & EDGE_FALLTHRU);
1422 gcc_assert (!last_stmt (a) || !stmt_ends_bb_p (last_stmt (a)));
1424 /* Remove labels from B and set gimple_bb to A for other statements. */
1425 for (gsi = gsi_start_bb (b); !gsi_end_p (gsi);)
1427 if (gimple_code (gsi_stmt (gsi)) == GIMPLE_LABEL)
1429 gimple label = gsi_stmt (gsi);
1431 gsi_remove (&gsi, false);
1433 /* Now that we can thread computed gotos, we might have
1434 a situation where we have a forced label in block B
1435 However, the label at the start of block B might still be
1436 used in other ways (think about the runtime checking for
1437 Fortran assigned gotos). So we can not just delete the
1438 label. Instead we move the label to the start of block A. */
1439 if (FORCED_LABEL (gimple_label_label (label)))
1441 gimple_stmt_iterator dest_gsi = gsi_start_bb (a);
1442 gsi_insert_before (&dest_gsi, label, GSI_NEW_STMT);
1447 gimple_set_bb (gsi_stmt (gsi), a);
1452 /* Merge the sequences. */
1453 last = gsi_last_bb (a);
1454 gsi_insert_seq_after (&last, bb_seq (b), GSI_NEW_STMT);
1455 set_bb_seq (b, NULL);
1457 if (cfgcleanup_altered_bbs)
1458 bitmap_set_bit (cfgcleanup_altered_bbs, a->index);
1462 /* Return the one of two successors of BB that is not reachable by a
1463 reached by a complex edge, if there is one. Else, return BB. We use
1464 this in optimizations that use post-dominators for their heuristics,
1465 to catch the cases in C++ where function calls are involved. */
1468 single_noncomplex_succ (basic_block bb)
1471 if (EDGE_COUNT (bb->succs) != 2)
1474 e0 = EDGE_SUCC (bb, 0);
1475 e1 = EDGE_SUCC (bb, 1);
1476 if (e0->flags & EDGE_COMPLEX)
1478 if (e1->flags & EDGE_COMPLEX)
1485 /* Walk the function tree removing unnecessary statements.
1487 * Empty statement nodes are removed
1489 * Unnecessary TRY_FINALLY and TRY_CATCH blocks are removed
1491 * Unnecessary COND_EXPRs are removed
1493 * Some unnecessary BIND_EXPRs are removed
1495 * GOTO_EXPRs immediately preceding destination are removed.
1497 Clearly more work could be done. The trick is doing the analysis
1498 and removal fast enough to be a net improvement in compile times.
1500 Note that when we remove a control structure such as a COND_EXPR
1501 BIND_EXPR, or TRY block, we will need to repeat this optimization pass
1502 to ensure we eliminate all the useless code. */
1511 gimple_stmt_iterator last_goto_gsi;
1515 static void remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *);
1517 /* Given a statement sequence, find the first executable statement with
1518 location information, and warn that it is unreachable. When searching,
1519 descend into containers in execution order. */
1522 remove_useless_stmts_warn_notreached (gimple_seq stmts)
1524 gimple_stmt_iterator gsi;
1526 for (gsi = gsi_start (stmts); !gsi_end_p (gsi); gsi_next (&gsi))
1528 gimple stmt = gsi_stmt (gsi);
1530 if (gimple_has_location (stmt))
1532 location_t loc = gimple_location (stmt);
1533 if (LOCATION_LINE (loc) > 0)
1535 warning (OPT_Wunreachable_code, "%Hwill never be executed", &loc);
1540 switch (gimple_code (stmt))
1542 /* Unfortunately, we need the CFG now to detect unreachable
1543 branches in a conditional, so conditionals are not handled here. */
1546 if (remove_useless_stmts_warn_notreached (gimple_try_eval (stmt)))
1548 if (remove_useless_stmts_warn_notreached (gimple_try_cleanup (stmt)))
1553 return remove_useless_stmts_warn_notreached (gimple_catch_handler (stmt));
1555 case GIMPLE_EH_FILTER:
1556 return remove_useless_stmts_warn_notreached (gimple_eh_filter_failure (stmt));
1559 return remove_useless_stmts_warn_notreached (gimple_bind_body (stmt));
1569 /* Helper for remove_useless_stmts_1. Handle GIMPLE_COND statements. */
1572 remove_useless_stmts_cond (gimple_stmt_iterator *gsi, struct rus_data *data)
1574 gimple stmt = gsi_stmt (*gsi);
1576 /* The folded result must still be a conditional statement. */
1578 gcc_assert (gsi_stmt (*gsi) == stmt);
1580 data->may_branch = true;
1582 /* Replace trivial conditionals with gotos. */
1583 if (gimple_cond_true_p (stmt))
1585 /* Goto THEN label. */
1586 tree then_label = gimple_cond_true_label (stmt);
1588 gsi_replace (gsi, gimple_build_goto (then_label), false);
1589 data->last_goto_gsi = *gsi;
1590 data->last_was_goto = true;
1591 data->repeat = true;
1593 else if (gimple_cond_false_p (stmt))
1595 /* Goto ELSE label. */
1596 tree else_label = gimple_cond_false_label (stmt);
1598 gsi_replace (gsi, gimple_build_goto (else_label), false);
1599 data->last_goto_gsi = *gsi;
1600 data->last_was_goto = true;
1601 data->repeat = true;
1605 tree then_label = gimple_cond_true_label (stmt);
1606 tree else_label = gimple_cond_false_label (stmt);
1608 if (then_label == else_label)
1610 /* Goto common destination. */
1611 gsi_replace (gsi, gimple_build_goto (then_label), false);
1612 data->last_goto_gsi = *gsi;
1613 data->last_was_goto = true;
1614 data->repeat = true;
1620 data->last_was_goto = false;
1623 /* Helper for remove_useless_stmts_1.
1624 Handle the try-finally case for GIMPLE_TRY statements. */
1627 remove_useless_stmts_tf (gimple_stmt_iterator *gsi, struct rus_data *data)
1629 bool save_may_branch, save_may_throw;
1630 bool this_may_branch, this_may_throw;
1632 gimple_seq eval_seq, cleanup_seq;
1633 gimple_stmt_iterator eval_gsi, cleanup_gsi;
1635 gimple stmt = gsi_stmt (*gsi);
1637 /* Collect may_branch and may_throw information for the body only. */
1638 save_may_branch = data->may_branch;
1639 save_may_throw = data->may_throw;
1640 data->may_branch = false;
1641 data->may_throw = false;
1642 data->last_was_goto = false;
1644 eval_seq = gimple_try_eval (stmt);
1645 eval_gsi = gsi_start (eval_seq);
1646 remove_useless_stmts_1 (&eval_gsi, data);
1648 this_may_branch = data->may_branch;
1649 this_may_throw = data->may_throw;
1650 data->may_branch |= save_may_branch;
1651 data->may_throw |= save_may_throw;
1652 data->last_was_goto = false;
1654 cleanup_seq = gimple_try_cleanup (stmt);
1655 cleanup_gsi = gsi_start (cleanup_seq);
1656 remove_useless_stmts_1 (&cleanup_gsi, data);
1658 /* If the body is empty, then we can emit the FINALLY block without
1659 the enclosing TRY_FINALLY_EXPR. */
1660 if (gimple_seq_empty_p (eval_seq))
1662 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1663 gsi_remove (gsi, false);
1664 data->repeat = true;
1667 /* If the handler is empty, then we can emit the TRY block without
1668 the enclosing TRY_FINALLY_EXPR. */
1669 else if (gimple_seq_empty_p (cleanup_seq))
1671 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1672 gsi_remove (gsi, false);
1673 data->repeat = true;
1676 /* If the body neither throws, nor branches, then we can safely
1677 string the TRY and FINALLY blocks together. */
1678 else if (!this_may_branch && !this_may_throw)
1680 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1681 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1682 gsi_remove (gsi, false);
1683 data->repeat = true;
1689 /* Helper for remove_useless_stmts_1.
1690 Handle the try-catch case for GIMPLE_TRY statements. */
1693 remove_useless_stmts_tc (gimple_stmt_iterator *gsi, struct rus_data *data)
1695 bool save_may_throw, this_may_throw;
1697 gimple_seq eval_seq, cleanup_seq, handler_seq, failure_seq;
1698 gimple_stmt_iterator eval_gsi, cleanup_gsi, handler_gsi, failure_gsi;
1700 gimple stmt = gsi_stmt (*gsi);
1702 /* Collect may_throw information for the body only. */
1703 save_may_throw = data->may_throw;
1704 data->may_throw = false;
1705 data->last_was_goto = false;
1707 eval_seq = gimple_try_eval (stmt);
1708 eval_gsi = gsi_start (eval_seq);
1709 remove_useless_stmts_1 (&eval_gsi, data);
1711 this_may_throw = data->may_throw;
1712 data->may_throw = save_may_throw;
1714 cleanup_seq = gimple_try_cleanup (stmt);
1716 /* If the body cannot throw, then we can drop the entire TRY_CATCH_EXPR. */
1717 if (!this_may_throw)
1719 if (warn_notreached)
1721 remove_useless_stmts_warn_notreached (cleanup_seq);
1723 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1724 gsi_remove (gsi, false);
1725 data->repeat = true;
1729 /* Process the catch clause specially. We may be able to tell that
1730 no exceptions propagate past this point. */
1732 this_may_throw = true;
1733 cleanup_gsi = gsi_start (cleanup_seq);
1734 stmt = gsi_stmt (cleanup_gsi);
1735 data->last_was_goto = false;
1737 switch (gimple_code (stmt))
1740 /* If the first element is a catch, they all must be. */
1741 while (!gsi_end_p (cleanup_gsi))
1743 stmt = gsi_stmt (cleanup_gsi);
1744 /* If we catch all exceptions, then the body does not
1745 propagate exceptions past this point. */
1746 if (gimple_catch_types (stmt) == NULL)
1747 this_may_throw = false;
1748 data->last_was_goto = false;
1749 handler_seq = gimple_catch_handler (stmt);
1750 handler_gsi = gsi_start (handler_seq);
1751 remove_useless_stmts_1 (&handler_gsi, data);
1752 gsi_next (&cleanup_gsi);
1757 case GIMPLE_EH_FILTER:
1758 /* If the first element is an eh_filter, it should stand alone. */
1759 if (gimple_eh_filter_must_not_throw (stmt))
1760 this_may_throw = false;
1761 else if (gimple_eh_filter_types (stmt) == NULL)
1762 this_may_throw = false;
1763 failure_seq = gimple_eh_filter_failure (stmt);
1764 failure_gsi = gsi_start (failure_seq);
1765 remove_useless_stmts_1 (&failure_gsi, data);
1770 /* Otherwise this is a list of cleanup statements. */
1771 remove_useless_stmts_1 (&cleanup_gsi, data);
1773 /* If the cleanup is empty, then we can emit the TRY block without
1774 the enclosing TRY_CATCH_EXPR. */
1775 if (gimple_seq_empty_p (cleanup_seq))
1777 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1778 gsi_remove(gsi, false);
1779 data->repeat = true;
1786 data->may_throw |= this_may_throw;
1789 /* Helper for remove_useless_stmts_1. Handle GIMPLE_BIND statements. */
1792 remove_useless_stmts_bind (gimple_stmt_iterator *gsi, struct rus_data *data ATTRIBUTE_UNUSED)
1795 gimple_seq body_seq, fn_body_seq;
1796 gimple_stmt_iterator body_gsi;
1798 gimple stmt = gsi_stmt (*gsi);
1800 /* First remove anything underneath the BIND_EXPR. */
1802 body_seq = gimple_bind_body (stmt);
1803 body_gsi = gsi_start (body_seq);
1804 remove_useless_stmts_1 (&body_gsi, data);
1806 /* If the GIMPLE_BIND has no variables, then we can pull everything
1807 up one level and remove the GIMPLE_BIND, unless this is the toplevel
1808 GIMPLE_BIND for the current function or an inlined function.
1810 When this situation occurs we will want to apply this
1811 optimization again. */
1812 block = gimple_bind_block (stmt);
1813 fn_body_seq = gimple_body (current_function_decl);
1814 if (gimple_bind_vars (stmt) == NULL_TREE
1815 && (gimple_seq_empty_p (fn_body_seq)
1816 || stmt != gimple_seq_first_stmt (fn_body_seq))
1818 || ! BLOCK_ABSTRACT_ORIGIN (block)
1819 || (TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block))
1822 tree var = NULL_TREE;
1823 /* Even if there are no gimple_bind_vars, there might be other
1824 decls in BLOCK_VARS rendering the GIMPLE_BIND not useless. */
1825 if (block && !BLOCK_NUM_NONLOCALIZED_VARS (block))
1826 for (var = BLOCK_VARS (block); var; var = TREE_CHAIN (var))
1827 if (TREE_CODE (var) == IMPORTED_DECL)
1829 if (var || (block && BLOCK_NUM_NONLOCALIZED_VARS (block)))
1833 gsi_insert_seq_before (gsi, body_seq, GSI_SAME_STMT);
1834 gsi_remove (gsi, false);
1835 data->repeat = true;
1842 /* Helper for remove_useless_stmts_1. Handle GIMPLE_GOTO statements. */
1845 remove_useless_stmts_goto (gimple_stmt_iterator *gsi, struct rus_data *data)
1847 gimple stmt = gsi_stmt (*gsi);
1849 tree dest = gimple_goto_dest (stmt);
1851 data->may_branch = true;
1852 data->last_was_goto = false;
1854 /* Record iterator for last goto expr, so that we can delete it if unnecessary. */
1855 if (TREE_CODE (dest) == LABEL_DECL)
1857 data->last_goto_gsi = *gsi;
1858 data->last_was_goto = true;
1864 /* Helper for remove_useless_stmts_1. Handle GIMPLE_LABEL statements. */
1867 remove_useless_stmts_label (gimple_stmt_iterator *gsi, struct rus_data *data)
1869 gimple stmt = gsi_stmt (*gsi);
1871 tree label = gimple_label_label (stmt);
1873 data->has_label = true;
1875 /* We do want to jump across non-local label receiver code. */
1876 if (DECL_NONLOCAL (label))
1877 data->last_was_goto = false;
1879 else if (data->last_was_goto
1880 && gimple_goto_dest (gsi_stmt (data->last_goto_gsi)) == label)
1882 /* Replace the preceding GIMPLE_GOTO statement with
1883 a GIMPLE_NOP, which will be subsequently removed.
1884 In this way, we avoid invalidating other iterators
1885 active on the statement sequence. */
1886 gsi_replace(&data->last_goto_gsi, gimple_build_nop(), false);
1887 data->last_was_goto = false;
1888 data->repeat = true;
1891 /* ??? Add something here to delete unused labels. */
1897 /* T is CALL_EXPR. Set current_function_calls_* flags. */
1900 notice_special_calls (gimple call)
1902 int flags = gimple_call_flags (call);
1904 if (flags & ECF_MAY_BE_ALLOCA)
1905 cfun->calls_alloca = true;
1906 if (flags & ECF_RETURNS_TWICE)
1907 cfun->calls_setjmp = true;
1911 /* Clear flags set by notice_special_calls. Used by dead code removal
1912 to update the flags. */
1915 clear_special_calls (void)
1917 cfun->calls_alloca = false;
1918 cfun->calls_setjmp = false;
1921 /* Remove useless statements from a statement sequence, and perform
1922 some preliminary simplifications. */
1925 remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *data)
1927 while (!gsi_end_p (*gsi))
1929 gimple stmt = gsi_stmt (*gsi);
1931 switch (gimple_code (stmt))
1934 remove_useless_stmts_cond (gsi, data);
1938 remove_useless_stmts_goto (gsi, data);
1942 remove_useless_stmts_label (gsi, data);
1947 stmt = gsi_stmt (*gsi);
1948 data->last_was_goto = false;
1949 if (stmt_could_throw_p (stmt))
1950 data->may_throw = true;
1956 data->last_was_goto = false;
1962 stmt = gsi_stmt (*gsi);
1963 data->last_was_goto = false;
1964 if (is_gimple_call (stmt))
1965 notice_special_calls (stmt);
1967 /* We used to call update_gimple_call_flags here,
1968 which copied side-effects and nothrows status
1969 from the function decl to the call. In the new
1970 tuplified GIMPLE, the accessors for this information
1971 always consult the function decl, so this copying
1972 is no longer necessary. */
1973 if (stmt_could_throw_p (stmt))
1974 data->may_throw = true;
1980 data->last_was_goto = false;
1981 data->may_branch = true;
1986 remove_useless_stmts_bind (gsi, data);
1990 if (gimple_try_kind (stmt) == GIMPLE_TRY_CATCH)
1991 remove_useless_stmts_tc (gsi, data);
1992 else if (gimple_try_kind (stmt) == GIMPLE_TRY_FINALLY)
1993 remove_useless_stmts_tf (gsi, data);
2003 gsi_remove (gsi, false);
2006 case GIMPLE_OMP_FOR:
2008 gimple_seq pre_body_seq = gimple_omp_for_pre_body (stmt);
2009 gimple_stmt_iterator pre_body_gsi = gsi_start (pre_body_seq);
2011 remove_useless_stmts_1 (&pre_body_gsi, data);
2012 data->last_was_goto = false;
2015 case GIMPLE_OMP_CRITICAL:
2016 case GIMPLE_OMP_CONTINUE:
2017 case GIMPLE_OMP_MASTER:
2018 case GIMPLE_OMP_ORDERED:
2019 case GIMPLE_OMP_SECTION:
2020 case GIMPLE_OMP_SECTIONS:
2021 case GIMPLE_OMP_SINGLE:
2023 gimple_seq body_seq = gimple_omp_body (stmt);
2024 gimple_stmt_iterator body_gsi = gsi_start (body_seq);
2026 remove_useless_stmts_1 (&body_gsi, data);
2027 data->last_was_goto = false;
2032 case GIMPLE_OMP_PARALLEL:
2033 case GIMPLE_OMP_TASK:
2035 /* Make sure the outermost GIMPLE_BIND isn't removed
2037 gimple_seq body_seq = gimple_omp_body (stmt);
2038 gimple bind = gimple_seq_first_stmt (body_seq);
2039 gimple_seq bind_seq = gimple_bind_body (bind);
2040 gimple_stmt_iterator bind_gsi = gsi_start (bind_seq);
2042 remove_useless_stmts_1 (&bind_gsi, data);
2043 data->last_was_goto = false;
2048 case GIMPLE_CHANGE_DYNAMIC_TYPE:
2049 /* If we do not optimize remove GIMPLE_CHANGE_DYNAMIC_TYPE as
2050 expansion is confused about them and we only remove them
2051 during alias computation otherwise. */
2054 data->last_was_goto = false;
2055 gsi_remove (gsi, false);
2061 data->last_was_goto = false;
2068 /* Walk the function tree, removing useless statements and performing
2069 some preliminary simplifications. */
2072 remove_useless_stmts (void)
2074 struct rus_data data;
2076 clear_special_calls ();
2080 gimple_stmt_iterator gsi;
2082 gsi = gsi_start (gimple_body (current_function_decl));
2083 memset (&data, 0, sizeof (data));
2084 remove_useless_stmts_1 (&gsi, &data);
2086 while (data.repeat);
2091 struct gimple_opt_pass pass_remove_useless_stmts =
2095 "useless", /* name */
2097 remove_useless_stmts, /* execute */
2100 0, /* static_pass_number */
2101 TV_NONE, /* tv_id */
2102 PROP_gimple_any, /* properties_required */
2103 0, /* properties_provided */
2104 0, /* properties_destroyed */
2105 0, /* todo_flags_start */
2106 TODO_dump_func /* todo_flags_finish */
2110 /* Remove PHI nodes associated with basic block BB and all edges out of BB. */
2113 remove_phi_nodes_and_edges_for_unreachable_block (basic_block bb)
2115 /* Since this block is no longer reachable, we can just delete all
2116 of its PHI nodes. */
2117 remove_phi_nodes (bb);
2119 /* Remove edges to BB's successors. */
2120 while (EDGE_COUNT (bb->succs) > 0)
2121 remove_edge (EDGE_SUCC (bb, 0));
2125 /* Remove statements of basic block BB. */
2128 remove_bb (basic_block bb)
2130 gimple_stmt_iterator i;
2131 source_location loc = UNKNOWN_LOCATION;
2135 fprintf (dump_file, "Removing basic block %d\n", bb->index);
2136 if (dump_flags & TDF_DETAILS)
2138 dump_bb (bb, dump_file, 0);
2139 fprintf (dump_file, "\n");
2145 struct loop *loop = bb->loop_father;
2147 /* If a loop gets removed, clean up the information associated
2149 if (loop->latch == bb
2150 || loop->header == bb)
2151 free_numbers_of_iterations_estimates_loop (loop);
2154 /* Remove all the instructions in the block. */
2155 if (bb_seq (bb) != NULL)
2157 for (i = gsi_start_bb (bb); !gsi_end_p (i);)
2159 gimple stmt = gsi_stmt (i);
2160 if (gimple_code (stmt) == GIMPLE_LABEL
2161 && (FORCED_LABEL (gimple_label_label (stmt))
2162 || DECL_NONLOCAL (gimple_label_label (stmt))))
2165 gimple_stmt_iterator new_gsi;
2167 /* A non-reachable non-local label may still be referenced.
2168 But it no longer needs to carry the extra semantics of
2170 if (DECL_NONLOCAL (gimple_label_label (stmt)))
2172 DECL_NONLOCAL (gimple_label_label (stmt)) = 0;
2173 FORCED_LABEL (gimple_label_label (stmt)) = 1;
2176 new_bb = bb->prev_bb;
2177 new_gsi = gsi_start_bb (new_bb);
2178 gsi_remove (&i, false);
2179 gsi_insert_before (&new_gsi, stmt, GSI_NEW_STMT);
2183 /* Release SSA definitions if we are in SSA. Note that we
2184 may be called when not in SSA. For example,
2185 final_cleanup calls this function via
2186 cleanup_tree_cfg. */
2187 if (gimple_in_ssa_p (cfun))
2188 release_defs (stmt);
2190 gsi_remove (&i, true);
2193 /* Don't warn for removed gotos. Gotos are often removed due to
2194 jump threading, thus resulting in bogus warnings. Not great,
2195 since this way we lose warnings for gotos in the original
2196 program that are indeed unreachable. */
2197 if (gimple_code (stmt) != GIMPLE_GOTO
2198 && gimple_has_location (stmt)
2200 loc = gimple_location (stmt);
2204 /* If requested, give a warning that the first statement in the
2205 block is unreachable. We walk statements backwards in the
2206 loop above, so the last statement we process is the first statement
2208 if (loc > BUILTINS_LOCATION && LOCATION_LINE (loc) > 0)
2209 warning (OPT_Wunreachable_code, "%Hwill never be executed", &loc);
2211 remove_phi_nodes_and_edges_for_unreachable_block (bb);
2212 bb->il.gimple = NULL;
2216 /* Given a basic block BB ending with COND_EXPR or SWITCH_EXPR, and a
2217 predicate VAL, return the edge that will be taken out of the block.
2218 If VAL does not match a unique edge, NULL is returned. */
2221 find_taken_edge (basic_block bb, tree val)
2225 stmt = last_stmt (bb);
2228 gcc_assert (is_ctrl_stmt (stmt));
2233 if (!is_gimple_min_invariant (val))
2236 if (gimple_code (stmt) == GIMPLE_COND)
2237 return find_taken_edge_cond_expr (bb, val);
2239 if (gimple_code (stmt) == GIMPLE_SWITCH)
2240 return find_taken_edge_switch_expr (bb, val);
2242 if (computed_goto_p (stmt))
2244 /* Only optimize if the argument is a label, if the argument is
2245 not a label then we can not construct a proper CFG.
2247 It may be the case that we only need to allow the LABEL_REF to
2248 appear inside an ADDR_EXPR, but we also allow the LABEL_REF to
2249 appear inside a LABEL_EXPR just to be safe. */
2250 if ((TREE_CODE (val) == ADDR_EXPR || TREE_CODE (val) == LABEL_EXPR)
2251 && TREE_CODE (TREE_OPERAND (val, 0)) == LABEL_DECL)
2252 return find_taken_edge_computed_goto (bb, TREE_OPERAND (val, 0));
2259 /* Given a constant value VAL and the entry block BB to a GOTO_EXPR
2260 statement, determine which of the outgoing edges will be taken out of the
2261 block. Return NULL if either edge may be taken. */
2264 find_taken_edge_computed_goto (basic_block bb, tree val)
2269 dest = label_to_block (val);
2272 e = find_edge (bb, dest);
2273 gcc_assert (e != NULL);
2279 /* Given a constant value VAL and the entry block BB to a COND_EXPR
2280 statement, determine which of the two edges will be taken out of the
2281 block. Return NULL if either edge may be taken. */
2284 find_taken_edge_cond_expr (basic_block bb, tree val)
2286 edge true_edge, false_edge;
2288 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
2290 gcc_assert (TREE_CODE (val) == INTEGER_CST);
2291 return (integer_zerop (val) ? false_edge : true_edge);
2294 /* Given an INTEGER_CST VAL and the entry block BB to a SWITCH_EXPR
2295 statement, determine which edge will be taken out of the block. Return
2296 NULL if any edge may be taken. */
2299 find_taken_edge_switch_expr (basic_block bb, tree val)
2301 basic_block dest_bb;
2306 switch_stmt = last_stmt (bb);
2307 taken_case = find_case_label_for_value (switch_stmt, val);
2308 dest_bb = label_to_block (CASE_LABEL (taken_case));
2310 e = find_edge (bb, dest_bb);
2316 /* Return the CASE_LABEL_EXPR that SWITCH_STMT will take for VAL.
2317 We can make optimal use here of the fact that the case labels are
2318 sorted: We can do a binary search for a case matching VAL. */
2321 find_case_label_for_value (gimple switch_stmt, tree val)
2323 size_t low, high, n = gimple_switch_num_labels (switch_stmt);
2324 tree default_case = gimple_switch_default_label (switch_stmt);
2326 for (low = 0, high = n; high - low > 1; )
2328 size_t i = (high + low) / 2;
2329 tree t = gimple_switch_label (switch_stmt, i);
2332 /* Cache the result of comparing CASE_LOW and val. */
2333 cmp = tree_int_cst_compare (CASE_LOW (t), val);
2340 if (CASE_HIGH (t) == NULL)
2342 /* A singe-valued case label. */
2348 /* A case range. We can only handle integer ranges. */
2349 if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
2354 return default_case;
2358 /* Dump a basic block on stderr. */
2361 gimple_debug_bb (basic_block bb)
2363 gimple_dump_bb (bb, stderr, 0, TDF_VOPS|TDF_MEMSYMS);
2367 /* Dump basic block with index N on stderr. */
2370 gimple_debug_bb_n (int n)
2372 gimple_debug_bb (BASIC_BLOCK (n));
2373 return BASIC_BLOCK (n);
2377 /* Dump the CFG on stderr.
2379 FLAGS are the same used by the tree dumping functions
2380 (see TDF_* in tree-pass.h). */
2383 gimple_debug_cfg (int flags)
2385 gimple_dump_cfg (stderr, flags);
2389 /* Dump the program showing basic block boundaries on the given FILE.
2391 FLAGS are the same used by the tree dumping functions (see TDF_* in
2395 gimple_dump_cfg (FILE *file, int flags)
2397 if (flags & TDF_DETAILS)
2399 const char *funcname
2400 = lang_hooks.decl_printable_name (current_function_decl, 2);
2403 fprintf (file, ";; Function %s\n\n", funcname);
2404 fprintf (file, ";; \n%d basic blocks, %d edges, last basic block %d.\n\n",
2405 n_basic_blocks, n_edges, last_basic_block);
2407 brief_dump_cfg (file);
2408 fprintf (file, "\n");
2411 if (flags & TDF_STATS)
2412 dump_cfg_stats (file);
2414 dump_function_to_file (current_function_decl, file, flags | TDF_BLOCKS);
2418 /* Dump CFG statistics on FILE. */
2421 dump_cfg_stats (FILE *file)
2423 static long max_num_merged_labels = 0;
2424 unsigned long size, total = 0;
2427 const char * const fmt_str = "%-30s%-13s%12s\n";
2428 const char * const fmt_str_1 = "%-30s%13d%11lu%c\n";
2429 const char * const fmt_str_2 = "%-30s%13ld%11lu%c\n";
2430 const char * const fmt_str_3 = "%-43s%11lu%c\n";
2431 const char *funcname
2432 = lang_hooks.decl_printable_name (current_function_decl, 2);
2435 fprintf (file, "\nCFG Statistics for %s\n\n", funcname);
2437 fprintf (file, "---------------------------------------------------------\n");
2438 fprintf (file, fmt_str, "", " Number of ", "Memory");
2439 fprintf (file, fmt_str, "", " instances ", "used ");
2440 fprintf (file, "---------------------------------------------------------\n");
2442 size = n_basic_blocks * sizeof (struct basic_block_def);
2444 fprintf (file, fmt_str_1, "Basic blocks", n_basic_blocks,
2445 SCALE (size), LABEL (size));
2449 num_edges += EDGE_COUNT (bb->succs);
2450 size = num_edges * sizeof (struct edge_def);
2452 fprintf (file, fmt_str_2, "Edges", num_edges, SCALE (size), LABEL (size));
2454 fprintf (file, "---------------------------------------------------------\n");
2455 fprintf (file, fmt_str_3, "Total memory used by CFG data", SCALE (total),
2457 fprintf (file, "---------------------------------------------------------\n");
2458 fprintf (file, "\n");
2460 if (cfg_stats.num_merged_labels > max_num_merged_labels)
2461 max_num_merged_labels = cfg_stats.num_merged_labels;
2463 fprintf (file, "Coalesced label blocks: %ld (Max so far: %ld)\n",
2464 cfg_stats.num_merged_labels, max_num_merged_labels);
2466 fprintf (file, "\n");
2470 /* Dump CFG statistics on stderr. Keep extern so that it's always
2471 linked in the final executable. */
2474 debug_cfg_stats (void)
2476 dump_cfg_stats (stderr);
2480 /* Dump the flowgraph to a .vcg FILE. */
2483 gimple_cfg2vcg (FILE *file)
2488 const char *funcname
2489 = lang_hooks.decl_printable_name (current_function_decl, 2);
2491 /* Write the file header. */
2492 fprintf (file, "graph: { title: \"%s\"\n", funcname);
2493 fprintf (file, "node: { title: \"ENTRY\" label: \"ENTRY\" }\n");
2494 fprintf (file, "node: { title: \"EXIT\" label: \"EXIT\" }\n");
2496 /* Write blocks and edges. */
2497 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
2499 fprintf (file, "edge: { sourcename: \"ENTRY\" targetname: \"%d\"",
2502 if (e->flags & EDGE_FAKE)
2503 fprintf (file, " linestyle: dotted priority: 10");
2505 fprintf (file, " linestyle: solid priority: 100");
2507 fprintf (file, " }\n");
2513 enum gimple_code head_code, end_code;
2514 const char *head_name, *end_name;
2517 gimple first = first_stmt (bb);
2518 gimple last = last_stmt (bb);
2522 head_code = gimple_code (first);
2523 head_name = gimple_code_name[head_code];
2524 head_line = get_lineno (first);
2527 head_name = "no-statement";
2531 end_code = gimple_code (last);
2532 end_name = gimple_code_name[end_code];
2533 end_line = get_lineno (last);
2536 end_name = "no-statement";
2538 fprintf (file, "node: { title: \"%d\" label: \"#%d\\n%s (%d)\\n%s (%d)\"}\n",
2539 bb->index, bb->index, head_name, head_line, end_name,
2542 FOR_EACH_EDGE (e, ei, bb->succs)
2544 if (e->dest == EXIT_BLOCK_PTR)
2545 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"EXIT\"", bb->index);
2547 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"%d\"", bb->index, e->dest->index);
2549 if (e->flags & EDGE_FAKE)
2550 fprintf (file, " priority: 10 linestyle: dotted");
2552 fprintf (file, " priority: 100 linestyle: solid");
2554 fprintf (file, " }\n");
2557 if (bb->next_bb != EXIT_BLOCK_PTR)
2561 fputs ("}\n\n", file);
2566 /*---------------------------------------------------------------------------
2567 Miscellaneous helpers
2568 ---------------------------------------------------------------------------*/
2570 /* Return true if T represents a stmt that always transfers control. */
2573 is_ctrl_stmt (gimple t)
2575 return gimple_code (t) == GIMPLE_COND
2576 || gimple_code (t) == GIMPLE_SWITCH
2577 || gimple_code (t) == GIMPLE_GOTO
2578 || gimple_code (t) == GIMPLE_RETURN
2579 || gimple_code (t) == GIMPLE_RESX;
2583 /* Return true if T is a statement that may alter the flow of control
2584 (e.g., a call to a non-returning function). */
2587 is_ctrl_altering_stmt (gimple t)
2591 if (is_gimple_call (t))
2593 int flags = gimple_call_flags (t);
2595 /* A non-pure/const call alters flow control if the current
2596 function has nonlocal labels. */
2597 if (!(flags & (ECF_CONST | ECF_PURE))
2598 && cfun->has_nonlocal_label)
2601 /* A call also alters control flow if it does not return. */
2602 if (gimple_call_flags (t) & ECF_NORETURN)
2606 /* OpenMP directives alter control flow. */
2607 if (is_gimple_omp (t))
2610 /* If a statement can throw, it alters control flow. */
2611 return stmt_can_throw_internal (t);
2615 /* Return true if T is a simple local goto. */
2618 simple_goto_p (gimple t)
2620 return (gimple_code (t) == GIMPLE_GOTO
2621 && TREE_CODE (gimple_goto_dest (t)) == LABEL_DECL);
2625 /* Return true if T can make an abnormal transfer of control flow.
2626 Transfers of control flow associated with EH are excluded. */
2629 stmt_can_make_abnormal_goto (gimple t)
2631 if (computed_goto_p (t))
2633 if (is_gimple_call (t))
2634 return gimple_has_side_effects (t) && cfun->has_nonlocal_label;
2639 /* Return true if STMT should start a new basic block. PREV_STMT is
2640 the statement preceding STMT. It is used when STMT is a label or a
2641 case label. Labels should only start a new basic block if their
2642 previous statement wasn't a label. Otherwise, sequence of labels
2643 would generate unnecessary basic blocks that only contain a single
2647 stmt_starts_bb_p (gimple stmt, gimple prev_stmt)
2652 /* Labels start a new basic block only if the preceding statement
2653 wasn't a label of the same type. This prevents the creation of
2654 consecutive blocks that have nothing but a single label. */
2655 if (gimple_code (stmt) == GIMPLE_LABEL)
2657 /* Nonlocal and computed GOTO targets always start a new block. */
2658 if (DECL_NONLOCAL (gimple_label_label (stmt))
2659 || FORCED_LABEL (gimple_label_label (stmt)))
2662 if (prev_stmt && gimple_code (prev_stmt) == GIMPLE_LABEL)
2664 if (DECL_NONLOCAL (gimple_label_label (prev_stmt)))
2667 cfg_stats.num_merged_labels++;
2678 /* Return true if T should end a basic block. */
2681 stmt_ends_bb_p (gimple t)
2683 return is_ctrl_stmt (t) || is_ctrl_altering_stmt (t);
2686 /* Remove block annotations and other data structures. */
2689 delete_tree_cfg_annotations (void)
2691 label_to_block_map = NULL;
2695 /* Return the first statement in basic block BB. */
2698 first_stmt (basic_block bb)
2700 gimple_stmt_iterator i = gsi_start_bb (bb);
2701 return !gsi_end_p (i) ? gsi_stmt (i) : NULL;
2704 /* Return the last statement in basic block BB. */
2707 last_stmt (basic_block bb)
2709 gimple_stmt_iterator b = gsi_last_bb (bb);
2710 return !gsi_end_p (b) ? gsi_stmt (b) : NULL;
2713 /* Return the last statement of an otherwise empty block. Return NULL
2714 if the block is totally empty, or if it contains more than one
2718 last_and_only_stmt (basic_block bb)
2720 gimple_stmt_iterator i = gsi_last_bb (bb);
2726 last = gsi_stmt (i);
2731 /* Empty statements should no longer appear in the instruction stream.
2732 Everything that might have appeared before should be deleted by
2733 remove_useless_stmts, and the optimizers should just gsi_remove
2734 instead of smashing with build_empty_stmt.
2736 Thus the only thing that should appear here in a block containing
2737 one executable statement is a label. */
2738 prev = gsi_stmt (i);
2739 if (gimple_code (prev) == GIMPLE_LABEL)
2745 /* Reinstall those PHI arguments queued in OLD_EDGE to NEW_EDGE. */
2748 reinstall_phi_args (edge new_edge, edge old_edge)
2750 edge_var_map_vector v;
2753 gimple_stmt_iterator phis;
2755 v = redirect_edge_var_map_vector (old_edge);
2759 for (i = 0, phis = gsi_start_phis (new_edge->dest);
2760 VEC_iterate (edge_var_map, v, i, vm) && !gsi_end_p (phis);
2761 i++, gsi_next (&phis))
2763 gimple phi = gsi_stmt (phis);
2764 tree result = redirect_edge_var_map_result (vm);
2765 tree arg = redirect_edge_var_map_def (vm);
2767 gcc_assert (result == gimple_phi_result (phi));
2769 add_phi_arg (phi, arg, new_edge);
2772 redirect_edge_var_map_clear (old_edge);
2775 /* Returns the basic block after which the new basic block created
2776 by splitting edge EDGE_IN should be placed. Tries to keep the new block
2777 near its "logical" location. This is of most help to humans looking
2778 at debugging dumps. */
2781 split_edge_bb_loc (edge edge_in)
2783 basic_block dest = edge_in->dest;
2785 if (dest->prev_bb && find_edge (dest->prev_bb, dest))
2786 return edge_in->src;
2788 return dest->prev_bb;
2791 /* Split a (typically critical) edge EDGE_IN. Return the new block.
2792 Abort on abnormal edges. */
2795 gimple_split_edge (edge edge_in)
2797 basic_block new_bb, after_bb, dest;
2800 /* Abnormal edges cannot be split. */
2801 gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
2803 dest = edge_in->dest;
2805 after_bb = split_edge_bb_loc (edge_in);
2807 new_bb = create_empty_bb (after_bb);
2808 new_bb->frequency = EDGE_FREQUENCY (edge_in);
2809 new_bb->count = edge_in->count;
2810 new_edge = make_edge (new_bb, dest, EDGE_FALLTHRU);
2811 new_edge->probability = REG_BR_PROB_BASE;
2812 new_edge->count = edge_in->count;
2814 e = redirect_edge_and_branch (edge_in, new_bb);
2815 gcc_assert (e == edge_in);
2816 reinstall_phi_args (new_edge, e);
2821 /* Callback for walk_tree, check that all elements with address taken are
2822 properly noticed as such. The DATA is an int* that is 1 if TP was seen
2823 inside a PHI node. */
2826 verify_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
2833 /* Check operand N for being valid GIMPLE and give error MSG if not. */
2834 #define CHECK_OP(N, MSG) \
2835 do { if (!is_gimple_val (TREE_OPERAND (t, N))) \
2836 { error (MSG); return TREE_OPERAND (t, N); }} while (0)
2838 switch (TREE_CODE (t))
2841 if (SSA_NAME_IN_FREE_LIST (t))
2843 error ("SSA name in freelist but still referenced");
2849 x = TREE_OPERAND (t, 0);
2850 if (!is_gimple_reg (x) && !is_gimple_min_invariant (x))
2852 error ("Indirect reference's operand is not a register or a constant.");
2858 x = fold (ASSERT_EXPR_COND (t));
2859 if (x == boolean_false_node)
2861 error ("ASSERT_EXPR with an always-false condition");
2867 error ("MODIFY_EXPR not expected while having tuples.");
2873 bool old_side_effects;
2875 bool new_side_effects;
2877 gcc_assert (is_gimple_address (t));
2879 old_constant = TREE_CONSTANT (t);
2880 old_side_effects = TREE_SIDE_EFFECTS (t);
2882 recompute_tree_invariant_for_addr_expr (t);
2883 new_side_effects = TREE_SIDE_EFFECTS (t);
2884 new_constant = TREE_CONSTANT (t);
2886 if (old_constant != new_constant)
2888 error ("constant not recomputed when ADDR_EXPR changed");
2891 if (old_side_effects != new_side_effects)
2893 error ("side effects not recomputed when ADDR_EXPR changed");
2897 /* Skip any references (they will be checked when we recurse down the
2898 tree) and ensure that any variable used as a prefix is marked
2900 for (x = TREE_OPERAND (t, 0);
2901 handled_component_p (x);
2902 x = TREE_OPERAND (x, 0))
2905 if (!(TREE_CODE (x) == VAR_DECL
2906 || TREE_CODE (x) == PARM_DECL
2907 || TREE_CODE (x) == RESULT_DECL))
2909 if (!TREE_ADDRESSABLE (x))
2911 error ("address taken, but ADDRESSABLE bit not set");
2914 if (DECL_GIMPLE_REG_P (x))
2916 error ("DECL_GIMPLE_REG_P set on a variable with address taken");
2924 x = COND_EXPR_COND (t);
2925 if (!INTEGRAL_TYPE_P (TREE_TYPE (x)))
2927 error ("non-integral used in condition");
2930 if (!is_gimple_condexpr (x))
2932 error ("invalid conditional operand");
2937 case NON_LVALUE_EXPR:
2941 case FIX_TRUNC_EXPR:
2946 case TRUTH_NOT_EXPR:
2947 CHECK_OP (0, "invalid operand to unary operator");
2954 case ARRAY_RANGE_REF:
2956 case VIEW_CONVERT_EXPR:
2957 /* We have a nest of references. Verify that each of the operands
2958 that determine where to reference is either a constant or a variable,
2959 verify that the base is valid, and then show we've already checked
2961 while (handled_component_p (t))
2963 if (TREE_CODE (t) == COMPONENT_REF && TREE_OPERAND (t, 2))
2964 CHECK_OP (2, "invalid COMPONENT_REF offset operator");
2965 else if (TREE_CODE (t) == ARRAY_REF
2966 || TREE_CODE (t) == ARRAY_RANGE_REF)
2968 CHECK_OP (1, "invalid array index");
2969 if (TREE_OPERAND (t, 2))
2970 CHECK_OP (2, "invalid array lower bound");
2971 if (TREE_OPERAND (t, 3))
2972 CHECK_OP (3, "invalid array stride");
2974 else if (TREE_CODE (t) == BIT_FIELD_REF)
2976 if (!host_integerp (TREE_OPERAND (t, 1), 1)
2977 || !host_integerp (TREE_OPERAND (t, 2), 1))
2979 error ("invalid position or size operand to BIT_FIELD_REF");
2982 else if (INTEGRAL_TYPE_P (TREE_TYPE (t))
2983 && (TYPE_PRECISION (TREE_TYPE (t))
2984 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
2986 error ("integral result type precision does not match "
2987 "field size of BIT_FIELD_REF");
2990 if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
2991 && (GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (t)))
2992 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
2994 error ("mode precision of non-integral result does not "
2995 "match field size of BIT_FIELD_REF");
3000 t = TREE_OPERAND (t, 0);
3003 if (!is_gimple_min_invariant (t) && !is_gimple_lvalue (t))
3005 error ("invalid reference prefix");
3012 /* PLUS_EXPR and MINUS_EXPR don't work on pointers, they should be done using
3013 POINTER_PLUS_EXPR. */
3014 if (POINTER_TYPE_P (TREE_TYPE (t)))
3016 error ("invalid operand to plus/minus, type is a pointer");
3019 CHECK_OP (0, "invalid operand to binary operator");
3020 CHECK_OP (1, "invalid operand to binary operator");
3023 case POINTER_PLUS_EXPR:
3024 /* Check to make sure the first operand is a pointer or reference type. */
3025 if (!POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 0))))
3027 error ("invalid operand to pointer plus, first operand is not a pointer");
3030 /* Check to make sure the second operand is an integer with type of
3032 if (!useless_type_conversion_p (sizetype,
3033 TREE_TYPE (TREE_OPERAND (t, 1))))
3035 error ("invalid operand to pointer plus, second operand is not an "
3036 "integer with type of sizetype.");
3046 case UNORDERED_EXPR:
3055 case TRUNC_DIV_EXPR:
3057 case FLOOR_DIV_EXPR:
3058 case ROUND_DIV_EXPR:
3059 case TRUNC_MOD_EXPR:
3061 case FLOOR_MOD_EXPR:
3062 case ROUND_MOD_EXPR:
3064 case EXACT_DIV_EXPR:
3074 CHECK_OP (0, "invalid operand to binary operator");
3075 CHECK_OP (1, "invalid operand to binary operator");
3079 if (TREE_CONSTANT (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
3092 /* Verify if EXPR is either a GIMPLE ID or a GIMPLE indirect reference.
3093 Returns true if there is an error, otherwise false. */
3096 verify_types_in_gimple_min_lval (tree expr)
3100 if (is_gimple_id (expr))
3103 if (!INDIRECT_REF_P (expr)
3104 && TREE_CODE (expr) != TARGET_MEM_REF)
3106 error ("invalid expression for min lvalue");
3110 /* TARGET_MEM_REFs are strange beasts. */
3111 if (TREE_CODE (expr) == TARGET_MEM_REF)
3114 op = TREE_OPERAND (expr, 0);
3115 if (!is_gimple_val (op))
3117 error ("invalid operand in indirect reference");
3118 debug_generic_stmt (op);
3121 if (!useless_type_conversion_p (TREE_TYPE (expr),
3122 TREE_TYPE (TREE_TYPE (op))))
3124 error ("type mismatch in indirect reference");
3125 debug_generic_stmt (TREE_TYPE (expr));
3126 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3133 /* Verify if EXPR is a valid GIMPLE reference expression. Returns true
3134 if there is an error, otherwise false. */
3137 verify_types_in_gimple_reference (tree expr)
3139 while (handled_component_p (expr))
3141 tree op = TREE_OPERAND (expr, 0);
3143 if (TREE_CODE (expr) == ARRAY_REF
3144 || TREE_CODE (expr) == ARRAY_RANGE_REF)
3146 if (!is_gimple_val (TREE_OPERAND (expr, 1))
3147 || (TREE_OPERAND (expr, 2)
3148 && !is_gimple_val (TREE_OPERAND (expr, 2)))
3149 || (TREE_OPERAND (expr, 3)
3150 && !is_gimple_val (TREE_OPERAND (expr, 3))))
3152 error ("invalid operands to array reference");
3153 debug_generic_stmt (expr);
3158 /* Verify if the reference array element types are compatible. */
3159 if (TREE_CODE (expr) == ARRAY_REF
3160 && !useless_type_conversion_p (TREE_TYPE (expr),
3161 TREE_TYPE (TREE_TYPE (op))))
3163 error ("type mismatch in array reference");
3164 debug_generic_stmt (TREE_TYPE (expr));
3165 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3168 if (TREE_CODE (expr) == ARRAY_RANGE_REF
3169 && !useless_type_conversion_p (TREE_TYPE (TREE_TYPE (expr)),
3170 TREE_TYPE (TREE_TYPE (op))))
3172 error ("type mismatch in array range reference");
3173 debug_generic_stmt (TREE_TYPE (TREE_TYPE (expr)));
3174 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3178 if ((TREE_CODE (expr) == REALPART_EXPR
3179 || TREE_CODE (expr) == IMAGPART_EXPR)
3180 && !useless_type_conversion_p (TREE_TYPE (expr),
3181 TREE_TYPE (TREE_TYPE (op))))
3183 error ("type mismatch in real/imagpart reference");
3184 debug_generic_stmt (TREE_TYPE (expr));
3185 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3189 if (TREE_CODE (expr) == COMPONENT_REF
3190 && !useless_type_conversion_p (TREE_TYPE (expr),
3191 TREE_TYPE (TREE_OPERAND (expr, 1))))
3193 error ("type mismatch in component reference");
3194 debug_generic_stmt (TREE_TYPE (expr));
3195 debug_generic_stmt (TREE_TYPE (TREE_OPERAND (expr, 1)));
3199 /* For VIEW_CONVERT_EXPRs which are allowed here, too, there
3200 is nothing to verify. Gross mismatches at most invoke
3201 undefined behavior. */
3202 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR
3203 && !handled_component_p (op))
3209 return verify_types_in_gimple_min_lval (expr);
3212 /* Returns true if there is one pointer type in TYPE_POINTER_TO (SRC_OBJ)
3213 list of pointer-to types that is trivially convertible to DEST. */
3216 one_pointer_to_useless_type_conversion_p (tree dest, tree src_obj)
3220 if (!TYPE_POINTER_TO (src_obj))
3223 for (src = TYPE_POINTER_TO (src_obj); src; src = TYPE_NEXT_PTR_TO (src))
3224 if (useless_type_conversion_p (dest, src))
3230 /* Return true if TYPE1 is a fixed-point type and if conversions to and
3231 from TYPE2 can be handled by FIXED_CONVERT_EXPR. */
3234 valid_fixed_convert_types_p (tree type1, tree type2)
3236 return (FIXED_POINT_TYPE_P (type1)
3237 && (INTEGRAL_TYPE_P (type2)
3238 || SCALAR_FLOAT_TYPE_P (type2)
3239 || FIXED_POINT_TYPE_P (type2)));
3242 /* Verify the contents of a GIMPLE_CALL STMT. Returns true when there
3243 is a problem, otherwise false. */
3246 verify_gimple_call (gimple stmt)
3248 tree fn = gimple_call_fn (stmt);
3251 if (!POINTER_TYPE_P (TREE_TYPE (fn))
3252 || (TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != FUNCTION_TYPE
3253 && TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != METHOD_TYPE))
3255 error ("non-function in gimple call");
3259 if (gimple_call_lhs (stmt)
3260 && !is_gimple_lvalue (gimple_call_lhs (stmt)))
3262 error ("invalid LHS in gimple call");
3266 fntype = TREE_TYPE (TREE_TYPE (fn));
3267 if (gimple_call_lhs (stmt)
3268 && !useless_type_conversion_p (TREE_TYPE (gimple_call_lhs (stmt)),
3270 /* ??? At least C++ misses conversions at assignments from
3271 void * call results.
3272 ??? Java is completely off. Especially with functions
3273 returning java.lang.Object.
3274 For now simply allow arbitrary pointer type conversions. */
3275 && !(POINTER_TYPE_P (TREE_TYPE (gimple_call_lhs (stmt)))
3276 && POINTER_TYPE_P (TREE_TYPE (fntype))))
3278 error ("invalid conversion in gimple call");
3279 debug_generic_stmt (TREE_TYPE (gimple_call_lhs (stmt)));
3280 debug_generic_stmt (TREE_TYPE (fntype));
3284 /* ??? The C frontend passes unpromoted arguments in case it
3285 didn't see a function declaration before the call. So for now
3286 leave the call arguments unverified. Once we gimplify
3287 unit-at-a-time we have a chance to fix this. */
3292 /* Verifies the gimple comparison with the result type TYPE and
3293 the operands OP0 and OP1. */
3296 verify_gimple_comparison (tree type, tree op0, tree op1)
3298 tree op0_type = TREE_TYPE (op0);
3299 tree op1_type = TREE_TYPE (op1);
3301 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3303 error ("invalid operands in gimple comparison");
3307 /* For comparisons we do not have the operations type as the
3308 effective type the comparison is carried out in. Instead
3309 we require that either the first operand is trivially
3310 convertible into the second, or the other way around.
3311 The resulting type of a comparison may be any integral type.
3312 Because we special-case pointers to void we allow
3313 comparisons of pointers with the same mode as well. */
3314 if ((!useless_type_conversion_p (op0_type, op1_type)
3315 && !useless_type_conversion_p (op1_type, op0_type)
3316 && (!POINTER_TYPE_P (op0_type)
3317 || !POINTER_TYPE_P (op1_type)
3318 || TYPE_MODE (op0_type) != TYPE_MODE (op1_type)))
3319 || !INTEGRAL_TYPE_P (type))
3321 error ("type mismatch in comparison expression");
3322 debug_generic_expr (type);
3323 debug_generic_expr (op0_type);
3324 debug_generic_expr (op1_type);
3331 /* Verify a gimple assignment statement STMT with an unary rhs.
3332 Returns true if anything is wrong. */
3335 verify_gimple_assign_unary (gimple stmt)
3337 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3338 tree lhs = gimple_assign_lhs (stmt);
3339 tree lhs_type = TREE_TYPE (lhs);
3340 tree rhs1 = gimple_assign_rhs1 (stmt);
3341 tree rhs1_type = TREE_TYPE (rhs1);
3343 if (!is_gimple_reg (lhs)
3345 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3347 error ("non-register as LHS of unary operation");
3351 if (!is_gimple_val (rhs1))
3353 error ("invalid operand in unary operation");
3357 /* First handle conversions. */
3362 /* Allow conversions between integral types and pointers only if
3363 there is no sign or zero extension involved.
3364 For targets were the precision of sizetype doesn't match that
3365 of pointers we need to allow arbitrary conversions from and
3367 if ((POINTER_TYPE_P (lhs_type)
3368 && INTEGRAL_TYPE_P (rhs1_type)
3369 && (TYPE_PRECISION (lhs_type) >= TYPE_PRECISION (rhs1_type)
3370 || rhs1_type == sizetype))
3371 || (POINTER_TYPE_P (rhs1_type)
3372 && INTEGRAL_TYPE_P (lhs_type)
3373 && (TYPE_PRECISION (rhs1_type) >= TYPE_PRECISION (lhs_type)
3374 || lhs_type == sizetype)))
3377 /* Allow conversion from integer to offset type and vice versa. */
3378 if ((TREE_CODE (lhs_type) == OFFSET_TYPE
3379 && TREE_CODE (rhs1_type) == INTEGER_TYPE)
3380 || (TREE_CODE (lhs_type) == INTEGER_TYPE
3381 && TREE_CODE (rhs1_type) == OFFSET_TYPE))
3384 /* Otherwise assert we are converting between types of the
3386 if (INTEGRAL_TYPE_P (lhs_type) != INTEGRAL_TYPE_P (rhs1_type))
3388 error ("invalid types in nop conversion");
3389 debug_generic_expr (lhs_type);
3390 debug_generic_expr (rhs1_type);
3397 case FIXED_CONVERT_EXPR:
3399 if (!valid_fixed_convert_types_p (lhs_type, rhs1_type)
3400 && !valid_fixed_convert_types_p (rhs1_type, lhs_type))
3402 error ("invalid types in fixed-point conversion");
3403 debug_generic_expr (lhs_type);
3404 debug_generic_expr (rhs1_type);
3413 if (!INTEGRAL_TYPE_P (rhs1_type) || !SCALAR_FLOAT_TYPE_P (lhs_type))
3415 error ("invalid types in conversion to floating point");
3416 debug_generic_expr (lhs_type);
3417 debug_generic_expr (rhs1_type);
3424 case FIX_TRUNC_EXPR:
3426 if (!INTEGRAL_TYPE_P (lhs_type) || !SCALAR_FLOAT_TYPE_P (rhs1_type))
3428 error ("invalid types in conversion to integer");
3429 debug_generic_expr (lhs_type);
3430 debug_generic_expr (rhs1_type);
3437 case VEC_UNPACK_HI_EXPR:
3438 case VEC_UNPACK_LO_EXPR:
3439 case REDUC_MAX_EXPR:
3440 case REDUC_MIN_EXPR:
3441 case REDUC_PLUS_EXPR:
3442 case VEC_UNPACK_FLOAT_HI_EXPR:
3443 case VEC_UNPACK_FLOAT_LO_EXPR:
3447 case TRUTH_NOT_EXPR:
3452 case NON_LVALUE_EXPR:
3460 /* For the remaining codes assert there is no conversion involved. */
3461 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3463 error ("non-trivial conversion in unary operation");
3464 debug_generic_expr (lhs_type);
3465 debug_generic_expr (rhs1_type);
3472 /* Verify a gimple assignment statement STMT with a binary rhs.
3473 Returns true if anything is wrong. */
3476 verify_gimple_assign_binary (gimple stmt)
3478 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3479 tree lhs = gimple_assign_lhs (stmt);
3480 tree lhs_type = TREE_TYPE (lhs);
3481 tree rhs1 = gimple_assign_rhs1 (stmt);
3482 tree rhs1_type = TREE_TYPE (rhs1);
3483 tree rhs2 = gimple_assign_rhs2 (stmt);
3484 tree rhs2_type = TREE_TYPE (rhs2);
3486 if (!is_gimple_reg (lhs)
3488 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3490 error ("non-register as LHS of binary operation");
3494 if (!is_gimple_val (rhs1)
3495 || !is_gimple_val (rhs2))
3497 error ("invalid operands in binary operation");
3501 /* First handle operations that involve different types. */
3506 if (TREE_CODE (lhs_type) != COMPLEX_TYPE
3507 || !(INTEGRAL_TYPE_P (rhs1_type)
3508 || SCALAR_FLOAT_TYPE_P (rhs1_type))
3509 || !(INTEGRAL_TYPE_P (rhs2_type)
3510 || SCALAR_FLOAT_TYPE_P (rhs2_type)))
3512 error ("type mismatch in complex expression");
3513 debug_generic_expr (lhs_type);
3514 debug_generic_expr (rhs1_type);
3515 debug_generic_expr (rhs2_type);
3527 /* Shifts and rotates are ok on integral types, fixed point
3528 types and integer vector types. */
3529 if ((!INTEGRAL_TYPE_P (rhs1_type)
3530 && !FIXED_POINT_TYPE_P (rhs1_type)
3531 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3532 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE))
3533 || (!INTEGRAL_TYPE_P (rhs2_type)
3534 /* Vector shifts of vectors are also ok. */
3535 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3536 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE
3537 && TREE_CODE (rhs2_type) == VECTOR_TYPE
3538 && TREE_CODE (TREE_TYPE (rhs2_type)) == INTEGER_TYPE))
3539 || !useless_type_conversion_p (lhs_type, rhs1_type))
3541 error ("type mismatch in shift expression");
3542 debug_generic_expr (lhs_type);
3543 debug_generic_expr (rhs1_type);
3544 debug_generic_expr (rhs2_type);
3551 case VEC_LSHIFT_EXPR:
3552 case VEC_RSHIFT_EXPR:
3554 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3555 || !(INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))
3556 || FIXED_POINT_TYPE_P (TREE_TYPE (rhs1_type)))
3557 || (!INTEGRAL_TYPE_P (rhs2_type)
3558 && (TREE_CODE (rhs2_type) != VECTOR_TYPE
3559 || !INTEGRAL_TYPE_P (TREE_TYPE (rhs2_type))))
3560 || !useless_type_conversion_p (lhs_type, rhs1_type))
3562 error ("type mismatch in vector shift expression");
3563 debug_generic_expr (lhs_type);
3564 debug_generic_expr (rhs1_type);
3565 debug_generic_expr (rhs2_type);
3574 /* We use regular PLUS_EXPR for vectors.
3575 ??? This just makes the checker happy and may not be what is
3577 if (TREE_CODE (lhs_type) == VECTOR_TYPE
3578 && POINTER_TYPE_P (TREE_TYPE (lhs_type)))
3580 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3581 || TREE_CODE (rhs2_type) != VECTOR_TYPE)
3583 error ("invalid non-vector operands to vector valued plus");
3586 lhs_type = TREE_TYPE (lhs_type);
3587 rhs1_type = TREE_TYPE (rhs1_type);
3588 rhs2_type = TREE_TYPE (rhs2_type);
3589 /* PLUS_EXPR is commutative, so we might end up canonicalizing
3590 the pointer to 2nd place. */
3591 if (POINTER_TYPE_P (rhs2_type))
3593 tree tem = rhs1_type;
3594 rhs1_type = rhs2_type;
3597 goto do_pointer_plus_expr_check;
3603 if (POINTER_TYPE_P (lhs_type)
3604 || POINTER_TYPE_P (rhs1_type)
3605 || POINTER_TYPE_P (rhs2_type))
3607 error ("invalid (pointer) operands to plus/minus");
3611 /* Continue with generic binary expression handling. */
3615 case POINTER_PLUS_EXPR:
3617 do_pointer_plus_expr_check:
3618 if (!POINTER_TYPE_P (rhs1_type)
3619 || !useless_type_conversion_p (lhs_type, rhs1_type)
3620 || !useless_type_conversion_p (sizetype, rhs2_type))
3622 error ("type mismatch in pointer plus expression");
3623 debug_generic_stmt (lhs_type);
3624 debug_generic_stmt (rhs1_type);
3625 debug_generic_stmt (rhs2_type);
3632 case TRUTH_ANDIF_EXPR:
3633 case TRUTH_ORIF_EXPR:
3636 case TRUTH_AND_EXPR:
3638 case TRUTH_XOR_EXPR:
3640 /* We allow any kind of integral typed argument and result. */
3641 if (!INTEGRAL_TYPE_P (rhs1_type)
3642 || !INTEGRAL_TYPE_P (rhs2_type)
3643 || !INTEGRAL_TYPE_P (lhs_type))
3645 error ("type mismatch in binary truth expression");
3646 debug_generic_expr (lhs_type);
3647 debug_generic_expr (rhs1_type);
3648 debug_generic_expr (rhs2_type);
3661 case UNORDERED_EXPR:
3669 /* Comparisons are also binary, but the result type is not
3670 connected to the operand types. */
3671 return verify_gimple_comparison (lhs_type, rhs1, rhs2);
3673 case WIDEN_SUM_EXPR:
3674 case WIDEN_MULT_EXPR:
3675 case VEC_WIDEN_MULT_HI_EXPR:
3676 case VEC_WIDEN_MULT_LO_EXPR:
3677 case VEC_PACK_TRUNC_EXPR:
3678 case VEC_PACK_SAT_EXPR:
3679 case VEC_PACK_FIX_TRUNC_EXPR:
3680 case VEC_EXTRACT_EVEN_EXPR:
3681 case VEC_EXTRACT_ODD_EXPR:
3682 case VEC_INTERLEAVE_HIGH_EXPR:
3683 case VEC_INTERLEAVE_LOW_EXPR:
3688 case TRUNC_DIV_EXPR:
3690 case FLOOR_DIV_EXPR:
3691 case ROUND_DIV_EXPR:
3692 case TRUNC_MOD_EXPR:
3694 case FLOOR_MOD_EXPR:
3695 case ROUND_MOD_EXPR:
3697 case EXACT_DIV_EXPR:
3703 /* Continue with generic binary expression handling. */
3710 if (!useless_type_conversion_p (lhs_type, rhs1_type)
3711 || !useless_type_conversion_p (lhs_type, rhs2_type))
3713 error ("type mismatch in binary expression");
3714 debug_generic_stmt (lhs_type);
3715 debug_generic_stmt (rhs1_type);
3716 debug_generic_stmt (rhs2_type);
3723 /* Verify a gimple assignment statement STMT with a single rhs.
3724 Returns true if anything is wrong. */
3727 verify_gimple_assign_single (gimple stmt)
3729 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3730 tree lhs = gimple_assign_lhs (stmt);
3731 tree lhs_type = TREE_TYPE (lhs);
3732 tree rhs1 = gimple_assign_rhs1 (stmt);
3733 tree rhs1_type = TREE_TYPE (rhs1);
3736 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3738 error ("non-trivial conversion at assignment");
3739 debug_generic_expr (lhs_type);
3740 debug_generic_expr (rhs1_type);
3744 if (handled_component_p (lhs))
3745 res |= verify_types_in_gimple_reference (lhs);
3747 /* Special codes we cannot handle via their class. */
3752 tree op = TREE_OPERAND (rhs1, 0);
3753 if (!is_gimple_addressable (op))
3755 error ("invalid operand in unary expression");
3759 if (!one_pointer_to_useless_type_conversion_p (lhs_type,
3762 error ("type mismatch in address expression");
3763 debug_generic_stmt (lhs_type);
3764 debug_generic_stmt (TYPE_POINTER_TO (TREE_TYPE (op)));
3768 return verify_types_in_gimple_reference (op);
3775 case ALIGN_INDIRECT_REF:
3776 case MISALIGNED_INDIRECT_REF:
3778 case ARRAY_RANGE_REF:
3779 case VIEW_CONVERT_EXPR:
3782 case TARGET_MEM_REF:
3783 if (!is_gimple_reg (lhs)
3784 && is_gimple_reg_type (TREE_TYPE (lhs)))
3786 error ("invalid rhs for gimple memory store");
3787 debug_generic_stmt (lhs);
3788 debug_generic_stmt (rhs1);
3791 return res || verify_types_in_gimple_reference (rhs1);
3803 /* tcc_declaration */
3808 if (!is_gimple_reg (lhs)
3809 && !is_gimple_reg (rhs1)
3810 && is_gimple_reg_type (TREE_TYPE (lhs)))
3812 error ("invalid rhs for gimple memory store");
3813 debug_generic_stmt (lhs);
3814 debug_generic_stmt (rhs1);
3823 case WITH_SIZE_EXPR:
3826 case POLYNOMIAL_CHREC:
3829 case REALIGN_LOAD_EXPR:
3839 /* Verify the contents of a GIMPLE_ASSIGN STMT. Returns true when there
3840 is a problem, otherwise false. */
3843 verify_gimple_assign (gimple stmt)
3845 switch (gimple_assign_rhs_class (stmt))
3847 case GIMPLE_SINGLE_RHS:
3848 return verify_gimple_assign_single (stmt);
3850 case GIMPLE_UNARY_RHS:
3851 return verify_gimple_assign_unary (stmt);
3853 case GIMPLE_BINARY_RHS:
3854 return verify_gimple_assign_binary (stmt);
3861 /* Verify the contents of a GIMPLE_RETURN STMT. Returns true when there
3862 is a problem, otherwise false. */
3865 verify_gimple_return (gimple stmt)
3867 tree op = gimple_return_retval (stmt);
3868 tree restype = TREE_TYPE (TREE_TYPE (cfun->decl));
3870 /* We cannot test for present return values as we do not fix up missing
3871 return values from the original source. */
3875 if (!is_gimple_val (op)
3876 && TREE_CODE (op) != RESULT_DECL)
3878 error ("invalid operand in return statement");
3879 debug_generic_stmt (op);
3883 if (!useless_type_conversion_p (restype, TREE_TYPE (op))
3884 /* ??? With C++ we can have the situation that the result
3885 decl is a reference type while the return type is an aggregate. */
3886 && !(TREE_CODE (op) == RESULT_DECL
3887 && TREE_CODE (TREE_TYPE (op)) == REFERENCE_TYPE
3888 && useless_type_conversion_p (restype, TREE_TYPE (TREE_TYPE (op)))))
3890 error ("invalid conversion in return statement");
3891 debug_generic_stmt (restype);
3892 debug_generic_stmt (TREE_TYPE (op));
3900 /* Verify the contents of a GIMPLE_GOTO STMT. Returns true when there
3901 is a problem, otherwise false. */
3904 verify_gimple_goto (gimple stmt)
3906 tree dest = gimple_goto_dest (stmt);
3908 /* ??? We have two canonical forms of direct goto destinations, a
3909 bare LABEL_DECL and an ADDR_EXPR of a LABEL_DECL. */
3910 if (TREE_CODE (dest) != LABEL_DECL
3911 && (!is_gimple_val (dest)
3912 || !POINTER_TYPE_P (TREE_TYPE (dest))))
3914 error ("goto destination is neither a label nor a pointer");
3921 /* Verify the contents of a GIMPLE_SWITCH STMT. Returns true when there
3922 is a problem, otherwise false. */
3925 verify_gimple_switch (gimple stmt)
3927 if (!is_gimple_val (gimple_switch_index (stmt)))
3929 error ("invalid operand to switch statement");
3930 debug_generic_stmt (gimple_switch_index (stmt));
3938 /* Verify the contents of a GIMPLE_PHI. Returns true if there is a problem,
3939 and false otherwise. */
3942 verify_gimple_phi (gimple stmt)
3944 tree type = TREE_TYPE (gimple_phi_result (stmt));
3947 if (!is_gimple_variable (gimple_phi_result (stmt)))
3949 error ("Invalid PHI result");
3953 for (i = 0; i < gimple_phi_num_args (stmt); i++)
3955 tree arg = gimple_phi_arg_def (stmt, i);
3956 if ((is_gimple_reg (gimple_phi_result (stmt))
3957 && !is_gimple_val (arg))
3958 || (!is_gimple_reg (gimple_phi_result (stmt))
3959 && !is_gimple_addressable (arg)))
3961 error ("Invalid PHI argument");
3962 debug_generic_stmt (arg);
3965 if (!useless_type_conversion_p (type, TREE_TYPE (arg)))
3967 error ("Incompatible types in PHI argument %u", i);
3968 debug_generic_stmt (type);
3969 debug_generic_stmt (TREE_TYPE (arg));
3978 /* Verify the GIMPLE statement STMT. Returns true if there is an
3979 error, otherwise false. */
3982 verify_types_in_gimple_stmt (gimple stmt)
3984 if (is_gimple_omp (stmt))
3986 /* OpenMP directives are validated by the FE and never operated
3987 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
3988 non-gimple expressions when the main index variable has had
3989 its address taken. This does not affect the loop itself
3990 because the header of an GIMPLE_OMP_FOR is merely used to determine
3991 how to setup the parallel iteration. */
3995 switch (gimple_code (stmt))
3998 return verify_gimple_assign (stmt);
4001 return TREE_CODE (gimple_label_label (stmt)) != LABEL_DECL;
4004 return verify_gimple_call (stmt);
4007 return verify_gimple_comparison (boolean_type_node,
4008 gimple_cond_lhs (stmt),
4009 gimple_cond_rhs (stmt));
4012 return verify_gimple_goto (stmt);
4015 return verify_gimple_switch (stmt);
4018 return verify_gimple_return (stmt);
4023 case GIMPLE_CHANGE_DYNAMIC_TYPE:
4024 return (!is_gimple_val (gimple_cdt_location (stmt))
4025 || !POINTER_TYPE_P (TREE_TYPE (gimple_cdt_location (stmt))));
4028 return verify_gimple_phi (stmt);
4030 /* Tuples that do not have tree operands. */
4033 case GIMPLE_PREDICT:
4041 /* Verify the GIMPLE statements inside the sequence STMTS. */
4044 verify_types_in_gimple_seq_2 (gimple_seq stmts)
4046 gimple_stmt_iterator ittr;
4049 for (ittr = gsi_start (stmts); !gsi_end_p (ittr); gsi_next (&ittr))
4051 gimple stmt = gsi_stmt (ittr);
4053 switch (gimple_code (stmt))
4056 err |= verify_types_in_gimple_seq_2 (gimple_bind_body (stmt));
4060 err |= verify_types_in_gimple_seq_2 (gimple_try_eval (stmt));
4061 err |= verify_types_in_gimple_seq_2 (gimple_try_cleanup (stmt));
4064 case GIMPLE_EH_FILTER:
4065 err |= verify_types_in_gimple_seq_2 (gimple_eh_filter_failure (stmt));
4069 err |= verify_types_in_gimple_seq_2 (gimple_catch_handler (stmt));
4074 bool err2 = verify_types_in_gimple_stmt (stmt);
4076 debug_gimple_stmt (stmt);
4086 /* Verify the GIMPLE statements inside the statement list STMTS. */
4089 verify_types_in_gimple_seq (gimple_seq stmts)
4091 if (verify_types_in_gimple_seq_2 (stmts))
4092 internal_error ("verify_gimple failed");
4096 /* Verify STMT, return true if STMT is not in GIMPLE form.
4097 TODO: Implement type checking. */
4100 verify_stmt (gimple_stmt_iterator *gsi)
4103 struct walk_stmt_info wi;
4104 bool last_in_block = gsi_one_before_end_p (*gsi);
4105 gimple stmt = gsi_stmt (*gsi);
4107 if (is_gimple_omp (stmt))
4109 /* OpenMP directives are validated by the FE and never operated
4110 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4111 non-gimple expressions when the main index variable has had
4112 its address taken. This does not affect the loop itself
4113 because the header of an GIMPLE_OMP_FOR is merely used to determine
4114 how to setup the parallel iteration. */
4118 /* FIXME. The C frontend passes unpromoted arguments in case it
4119 didn't see a function declaration before the call. */
4120 if (is_gimple_call (stmt))
4124 if (!is_gimple_call_addr (gimple_call_fn (stmt)))
4126 error ("invalid function in call statement");
4130 decl = gimple_call_fndecl (stmt);
4132 && TREE_CODE (decl) == FUNCTION_DECL
4133 && DECL_LOOPING_CONST_OR_PURE_P (decl)
4134 && (!DECL_PURE_P (decl))
4135 && (!TREE_READONLY (decl)))
4137 error ("invalid pure const state for function");
4142 memset (&wi, 0, sizeof (wi));
4143 addr = walk_gimple_op (gsi_stmt (*gsi), verify_expr, &wi);
4146 debug_generic_expr (addr);
4147 inform (input_location, "in statement");
4148 debug_gimple_stmt (stmt);
4152 /* If the statement is marked as part of an EH region, then it is
4153 expected that the statement could throw. Verify that when we
4154 have optimizations that simplify statements such that we prove
4155 that they cannot throw, that we update other data structures
4157 if (lookup_stmt_eh_region (stmt) >= 0)
4159 /* During IPA passes, ipa-pure-const sets nothrow flags on calls
4160 and they are updated on statements only after fixup_cfg
4161 is executed at beggining of expansion stage. */
4162 if (!stmt_could_throw_p (stmt) && cgraph_state != CGRAPH_STATE_IPA_SSA)
4164 error ("statement marked for throw, but doesn%'t");
4167 if (!last_in_block && stmt_can_throw_internal (stmt))
4169 error ("statement marked for throw in middle of block");
4177 debug_gimple_stmt (stmt);
4182 /* Return true when the T can be shared. */
4185 tree_node_can_be_shared (tree t)
4187 if (IS_TYPE_OR_DECL_P (t)
4188 || is_gimple_min_invariant (t)
4189 || TREE_CODE (t) == SSA_NAME
4190 || t == error_mark_node
4191 || TREE_CODE (t) == IDENTIFIER_NODE)
4194 if (TREE_CODE (t) == CASE_LABEL_EXPR)
4197 while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4198 && is_gimple_min_invariant (TREE_OPERAND (t, 1)))
4199 || TREE_CODE (t) == COMPONENT_REF
4200 || TREE_CODE (t) == REALPART_EXPR
4201 || TREE_CODE (t) == IMAGPART_EXPR)
4202 t = TREE_OPERAND (t, 0);
4211 /* Called via walk_gimple_stmt. Verify tree sharing. */
4214 verify_node_sharing (tree *tp, int *walk_subtrees, void *data)
4216 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
4217 struct pointer_set_t *visited = (struct pointer_set_t *) wi->info;
4219 if (tree_node_can_be_shared (*tp))
4221 *walk_subtrees = false;
4225 if (pointer_set_insert (visited, *tp))
4232 static bool eh_error_found;
4234 verify_eh_throw_stmt_node (void **slot, void *data)
4236 struct throw_stmt_node *node = (struct throw_stmt_node *)*slot;
4237 struct pointer_set_t *visited = (struct pointer_set_t *) data;
4239 if (!pointer_set_contains (visited, node->stmt))
4241 error ("Dead STMT in EH table");
4242 debug_gimple_stmt (node->stmt);
4243 eh_error_found = true;
4249 /* Verify the GIMPLE statements in every basic block. */
4255 gimple_stmt_iterator gsi;
4257 struct pointer_set_t *visited, *visited_stmts;
4259 struct walk_stmt_info wi;
4261 timevar_push (TV_TREE_STMT_VERIFY);
4262 visited = pointer_set_create ();
4263 visited_stmts = pointer_set_create ();
4265 memset (&wi, 0, sizeof (wi));
4266 wi.info = (void *) visited;
4273 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4275 phi = gsi_stmt (gsi);
4276 pointer_set_insert (visited_stmts, phi);
4277 if (gimple_bb (phi) != bb)
4279 error ("gimple_bb (phi) is set to a wrong basic block");
4283 for (i = 0; i < gimple_phi_num_args (phi); i++)
4285 tree t = gimple_phi_arg_def (phi, i);
4290 error ("missing PHI def");
4291 debug_gimple_stmt (phi);
4295 /* Addressable variables do have SSA_NAMEs but they
4296 are not considered gimple values. */
4297 else if (TREE_CODE (t) != SSA_NAME
4298 && TREE_CODE (t) != FUNCTION_DECL
4299 && !is_gimple_min_invariant (t))
4301 error ("PHI argument is not a GIMPLE value");
4302 debug_gimple_stmt (phi);
4303 debug_generic_expr (t);
4307 addr = walk_tree (&t, verify_node_sharing, visited, NULL);
4310 error ("incorrect sharing of tree nodes");
4311 debug_gimple_stmt (phi);
4312 debug_generic_expr (addr);
4318 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); )
4320 gimple stmt = gsi_stmt (gsi);
4322 if (gimple_code (stmt) == GIMPLE_WITH_CLEANUP_EXPR
4323 || gimple_code (stmt) == GIMPLE_BIND)
4325 error ("invalid GIMPLE statement");
4326 debug_gimple_stmt (stmt);
4330 pointer_set_insert (visited_stmts, stmt);
4332 if (gimple_bb (stmt) != bb)
4334 error ("gimple_bb (stmt) is set to a wrong basic block");
4338 if (gimple_code (stmt) == GIMPLE_LABEL)
4340 tree decl = gimple_label_label (stmt);
4341 int uid = LABEL_DECL_UID (decl);
4344 || VEC_index (basic_block, label_to_block_map, uid) != bb)
4346 error ("incorrect entry in label_to_block_map.\n");
4351 err |= verify_stmt (&gsi);
4352 addr = walk_gimple_op (gsi_stmt (gsi), verify_node_sharing, &wi);
4355 error ("incorrect sharing of tree nodes");
4356 debug_gimple_stmt (stmt);
4357 debug_generic_expr (addr);
4364 eh_error_found = false;
4365 if (get_eh_throw_stmt_table (cfun))
4366 htab_traverse (get_eh_throw_stmt_table (cfun),
4367 verify_eh_throw_stmt_node,
4370 if (err | eh_error_found)
4371 internal_error ("verify_stmts failed");
4373 pointer_set_destroy (visited);
4374 pointer_set_destroy (visited_stmts);
4375 verify_histograms ();
4376 timevar_pop (TV_TREE_STMT_VERIFY);
4380 /* Verifies that the flow information is OK. */
4383 gimple_verify_flow_info (void)
4387 gimple_stmt_iterator gsi;
4392 if (ENTRY_BLOCK_PTR->il.gimple)
4394 error ("ENTRY_BLOCK has IL associated with it");
4398 if (EXIT_BLOCK_PTR->il.gimple)
4400 error ("EXIT_BLOCK has IL associated with it");
4404 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4405 if (e->flags & EDGE_FALLTHRU)
4407 error ("fallthru to exit from bb %d", e->src->index);
4413 bool found_ctrl_stmt = false;
4417 /* Skip labels on the start of basic block. */
4418 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4421 gimple prev_stmt = stmt;
4423 stmt = gsi_stmt (gsi);
4425 if (gimple_code (stmt) != GIMPLE_LABEL)
4428 label = gimple_label_label (stmt);
4429 if (prev_stmt && DECL_NONLOCAL (label))
4431 error ("nonlocal label ");
4432 print_generic_expr (stderr, label, 0);
4433 fprintf (stderr, " is not first in a sequence of labels in bb %d",
4438 if (label_to_block (label) != bb)
4441 print_generic_expr (stderr, label, 0);
4442 fprintf (stderr, " to block does not match in bb %d",
4447 if (decl_function_context (label) != current_function_decl)
4450 print_generic_expr (stderr, label, 0);
4451 fprintf (stderr, " has incorrect context in bb %d",
4457 /* Verify that body of basic block BB is free of control flow. */
4458 for (; !gsi_end_p (gsi); gsi_next (&gsi))
4460 gimple stmt = gsi_stmt (gsi);
4462 if (found_ctrl_stmt)
4464 error ("control flow in the middle of basic block %d",
4469 if (stmt_ends_bb_p (stmt))
4470 found_ctrl_stmt = true;
4472 if (gimple_code (stmt) == GIMPLE_LABEL)
4475 print_generic_expr (stderr, gimple_label_label (stmt), 0);
4476 fprintf (stderr, " in the middle of basic block %d", bb->index);
4481 gsi = gsi_last_bb (bb);
4482 if (gsi_end_p (gsi))
4485 stmt = gsi_stmt (gsi);
4487 err |= verify_eh_edges (stmt);
4489 if (is_ctrl_stmt (stmt))
4491 FOR_EACH_EDGE (e, ei, bb->succs)
4492 if (e->flags & EDGE_FALLTHRU)
4494 error ("fallthru edge after a control statement in bb %d",
4500 if (gimple_code (stmt) != GIMPLE_COND)
4502 /* Verify that there are no edges with EDGE_TRUE/FALSE_FLAG set
4503 after anything else but if statement. */
4504 FOR_EACH_EDGE (e, ei, bb->succs)
4505 if (e->flags & (EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))
4507 error ("true/false edge after a non-GIMPLE_COND in bb %d",
4513 switch (gimple_code (stmt))
4520 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
4524 || !(true_edge->flags & EDGE_TRUE_VALUE)
4525 || !(false_edge->flags & EDGE_FALSE_VALUE)
4526 || (true_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4527 || (false_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4528 || EDGE_COUNT (bb->succs) >= 3)
4530 error ("wrong outgoing edge flags at end of bb %d",
4538 if (simple_goto_p (stmt))
4540 error ("explicit goto at end of bb %d", bb->index);
4545 /* FIXME. We should double check that the labels in the
4546 destination blocks have their address taken. */
4547 FOR_EACH_EDGE (e, ei, bb->succs)
4548 if ((e->flags & (EDGE_FALLTHRU | EDGE_TRUE_VALUE
4549 | EDGE_FALSE_VALUE))
4550 || !(e->flags & EDGE_ABNORMAL))
4552 error ("wrong outgoing edge flags at end of bb %d",
4560 if (!single_succ_p (bb)
4561 || (single_succ_edge (bb)->flags
4562 & (EDGE_FALLTHRU | EDGE_ABNORMAL
4563 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4565 error ("wrong outgoing edge flags at end of bb %d", bb->index);
4568 if (single_succ (bb) != EXIT_BLOCK_PTR)
4570 error ("return edge does not point to exit in bb %d",
4582 n = gimple_switch_num_labels (stmt);
4584 /* Mark all the destination basic blocks. */
4585 for (i = 0; i < n; ++i)
4587 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4588 basic_block label_bb = label_to_block (lab);
4589 gcc_assert (!label_bb->aux || label_bb->aux == (void *)1);
4590 label_bb->aux = (void *)1;
4593 /* Verify that the case labels are sorted. */
4594 prev = gimple_switch_label (stmt, 0);
4595 for (i = 1; i < n; ++i)
4597 tree c = gimple_switch_label (stmt, i);
4600 error ("found default case not at the start of "
4606 && !tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c)))
4608 error ("case labels not sorted: ");
4609 print_generic_expr (stderr, prev, 0);
4610 fprintf (stderr," is greater than ");
4611 print_generic_expr (stderr, c, 0);
4612 fprintf (stderr," but comes before it.\n");
4617 /* VRP will remove the default case if it can prove it will
4618 never be executed. So do not verify there always exists
4619 a default case here. */
4621 FOR_EACH_EDGE (e, ei, bb->succs)
4625 error ("extra outgoing edge %d->%d",
4626 bb->index, e->dest->index);
4630 e->dest->aux = (void *)2;
4631 if ((e->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL
4632 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4634 error ("wrong outgoing edge flags at end of bb %d",
4640 /* Check that we have all of them. */
4641 for (i = 0; i < n; ++i)
4643 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4644 basic_block label_bb = label_to_block (lab);
4646 if (label_bb->aux != (void *)2)
4648 error ("missing edge %i->%i", bb->index, label_bb->index);
4653 FOR_EACH_EDGE (e, ei, bb->succs)
4654 e->dest->aux = (void *)0;
4661 if (dom_info_state (CDI_DOMINATORS) >= DOM_NO_FAST_QUERY)
4662 verify_dominators (CDI_DOMINATORS);
4668 /* Updates phi nodes after creating a forwarder block joined
4669 by edge FALLTHRU. */
4672 gimple_make_forwarder_block (edge fallthru)
4676 basic_block dummy, bb;
4678 gimple_stmt_iterator gsi;
4680 dummy = fallthru->src;
4681 bb = fallthru->dest;
4683 if (single_pred_p (bb))
4686 /* If we redirected a branch we must create new PHI nodes at the
4688 for (gsi = gsi_start_phis (dummy); !gsi_end_p (gsi); gsi_next (&gsi))
4690 gimple phi, new_phi;
4692 phi = gsi_stmt (gsi);
4693 var = gimple_phi_result (phi);
4694 new_phi = create_phi_node (var, bb);
4695 SSA_NAME_DEF_STMT (var) = new_phi;
4696 gimple_phi_set_result (phi, make_ssa_name (SSA_NAME_VAR (var), phi));
4697 add_phi_arg (new_phi, gimple_phi_result (phi), fallthru);
4700 /* Add the arguments we have stored on edges. */
4701 FOR_EACH_EDGE (e, ei, bb->preds)
4706 flush_pending_stmts (e);
4711 /* Return a non-special label in the head of basic block BLOCK.
4712 Create one if it doesn't exist. */
4715 gimple_block_label (basic_block bb)
4717 gimple_stmt_iterator i, s = gsi_start_bb (bb);
4722 for (i = s; !gsi_end_p (i); first = false, gsi_next (&i))
4724 stmt = gsi_stmt (i);
4725 if (gimple_code (stmt) != GIMPLE_LABEL)
4727 label = gimple_label_label (stmt);
4728 if (!DECL_NONLOCAL (label))
4731 gsi_move_before (&i, &s);
4736 label = create_artificial_label ();
4737 stmt = gimple_build_label (label);
4738 gsi_insert_before (&s, stmt, GSI_NEW_STMT);
4743 /* Attempt to perform edge redirection by replacing a possibly complex
4744 jump instruction by a goto or by removing the jump completely.
4745 This can apply only if all edges now point to the same block. The
4746 parameters and return values are equivalent to
4747 redirect_edge_and_branch. */
4750 gimple_try_redirect_by_replacing_jump (edge e, basic_block target)
4752 basic_block src = e->src;
4753 gimple_stmt_iterator i;
4756 /* We can replace or remove a complex jump only when we have exactly
4758 if (EDGE_COUNT (src->succs) != 2
4759 /* Verify that all targets will be TARGET. Specifically, the
4760 edge that is not E must also go to TARGET. */
4761 || EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)
4764 i = gsi_last_bb (src);
4768 stmt = gsi_stmt (i);
4770 if (gimple_code (stmt) == GIMPLE_COND || gimple_code (stmt) == GIMPLE_SWITCH)
4772 gsi_remove (&i, true);
4773 e = ssa_redirect_edge (e, target);
4774 e->flags = EDGE_FALLTHRU;
4782 /* Redirect E to DEST. Return NULL on failure. Otherwise, return the
4783 edge representing the redirected branch. */
4786 gimple_redirect_edge_and_branch (edge e, basic_block dest)
4788 basic_block bb = e->src;
4789 gimple_stmt_iterator gsi;
4793 if (e->flags & EDGE_ABNORMAL)
4796 if (e->src != ENTRY_BLOCK_PTR
4797 && (ret = gimple_try_redirect_by_replacing_jump (e, dest)))
4800 if (e->dest == dest)
4803 gsi = gsi_last_bb (bb);
4804 stmt = gsi_end_p (gsi) ? NULL : gsi_stmt (gsi);
4806 switch (stmt ? gimple_code (stmt) : ERROR_MARK)
4809 /* For COND_EXPR, we only need to redirect the edge. */
4813 /* No non-abnormal edges should lead from a non-simple goto, and
4814 simple ones should be represented implicitly. */
4819 tree label = gimple_block_label (dest);
4820 tree cases = get_cases_for_edge (e, stmt);
4822 /* If we have a list of cases associated with E, then use it
4823 as it's a lot faster than walking the entire case vector. */
4826 edge e2 = find_edge (e->src, dest);
4833 CASE_LABEL (cases) = label;
4834 cases = TREE_CHAIN (cases);
4837 /* If there was already an edge in the CFG, then we need
4838 to move all the cases associated with E to E2. */
4841 tree cases2 = get_cases_for_edge (e2, stmt);
4843 TREE_CHAIN (last) = TREE_CHAIN (cases2);
4844 TREE_CHAIN (cases2) = first;
4849 size_t i, n = gimple_switch_num_labels (stmt);
4851 for (i = 0; i < n; i++)
4853 tree elt = gimple_switch_label (stmt, i);
4854 if (label_to_block (CASE_LABEL (elt)) == e->dest)
4855 CASE_LABEL (elt) = label;
4863 gsi_remove (&gsi, true);
4864 e->flags |= EDGE_FALLTHRU;
4867 case GIMPLE_OMP_RETURN:
4868 case GIMPLE_OMP_CONTINUE:
4869 case GIMPLE_OMP_SECTIONS_SWITCH:
4870 case GIMPLE_OMP_FOR:
4871 /* The edges from OMP constructs can be simply redirected. */
4875 /* Otherwise it must be a fallthru edge, and we don't need to
4876 do anything besides redirecting it. */
4877 gcc_assert (e->flags & EDGE_FALLTHRU);
4881 /* Update/insert PHI nodes as necessary. */
4883 /* Now update the edges in the CFG. */
4884 e = ssa_redirect_edge (e, dest);
4889 /* Returns true if it is possible to remove edge E by redirecting
4890 it to the destination of the other edge from E->src. */
4893 gimple_can_remove_branch_p (const_edge e)
4895 if (e->flags & (EDGE_ABNORMAL | EDGE_EH))
4901 /* Simple wrapper, as we can always redirect fallthru edges. */
4904 gimple_redirect_edge_and_branch_force (edge e, basic_block dest)
4906 e = gimple_redirect_edge_and_branch (e, dest);
4913 /* Splits basic block BB after statement STMT (but at least after the
4914 labels). If STMT is NULL, BB is split just after the labels. */
4917 gimple_split_block (basic_block bb, void *stmt)
4919 gimple_stmt_iterator gsi;
4920 gimple_stmt_iterator gsi_tgt;
4927 new_bb = create_empty_bb (bb);
4929 /* Redirect the outgoing edges. */
4930 new_bb->succs = bb->succs;
4932 FOR_EACH_EDGE (e, ei, new_bb->succs)
4935 if (stmt && gimple_code ((gimple) stmt) == GIMPLE_LABEL)
4938 /* Move everything from GSI to the new basic block. */
4939 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4941 act = gsi_stmt (gsi);
4942 if (gimple_code (act) == GIMPLE_LABEL)
4955 if (gsi_end_p (gsi))
4958 /* Split the statement list - avoid re-creating new containers as this
4959 brings ugly quadratic memory consumption in the inliner.
4960 (We are still quadratic since we need to update stmt BB pointers,
4962 list = gsi_split_seq_before (&gsi);
4963 set_bb_seq (new_bb, list);
4964 for (gsi_tgt = gsi_start (list);
4965 !gsi_end_p (gsi_tgt); gsi_next (&gsi_tgt))
4966 gimple_set_bb (gsi_stmt (gsi_tgt), new_bb);
4972 /* Moves basic block BB after block AFTER. */
4975 gimple_move_block_after (basic_block bb, basic_block after)
4977 if (bb->prev_bb == after)
4981 link_block (bb, after);
4987 /* Return true if basic_block can be duplicated. */
4990 gimple_can_duplicate_bb_p (const_basic_block bb ATTRIBUTE_UNUSED)
4995 /* Create a duplicate of the basic block BB. NOTE: This does not
4996 preserve SSA form. */
4999 gimple_duplicate_bb (basic_block bb)
5002 gimple_stmt_iterator gsi, gsi_tgt;
5003 gimple_seq phis = phi_nodes (bb);
5004 gimple phi, stmt, copy;
5006 new_bb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb);
5008 /* Copy the PHI nodes. We ignore PHI node arguments here because
5009 the incoming edges have not been setup yet. */
5010 for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
5012 phi = gsi_stmt (gsi);
5013 copy = create_phi_node (gimple_phi_result (phi), new_bb);
5014 create_new_def_for (gimple_phi_result (copy), copy,
5015 gimple_phi_result_ptr (copy));
5018 gsi_tgt = gsi_start_bb (new_bb);
5019 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5021 def_operand_p def_p;
5022 ssa_op_iter op_iter;
5025 stmt = gsi_stmt (gsi);
5026 if (gimple_code (stmt) == GIMPLE_LABEL)
5029 /* Create a new copy of STMT and duplicate STMT's virtual
5031 copy = gimple_copy (stmt);
5032 gsi_insert_after (&gsi_tgt, copy, GSI_NEW_STMT);
5033 region = lookup_stmt_eh_region (stmt);
5035 add_stmt_to_eh_region (copy, region);
5036 gimple_duplicate_stmt_histograms (cfun, copy, cfun, stmt);
5038 /* Create new names for all the definitions created by COPY and
5039 add replacement mappings for each new name. */
5040 FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS)
5041 create_new_def_for (DEF_FROM_PTR (def_p), copy, def_p);
5047 /* Adds phi node arguments for edge E_COPY after basic block duplication. */
5050 add_phi_args_after_copy_edge (edge e_copy)
5052 basic_block bb, bb_copy = e_copy->src, dest;
5055 gimple phi, phi_copy;
5057 gimple_stmt_iterator psi, psi_copy;
5059 if (gimple_seq_empty_p (phi_nodes (e_copy->dest)))
5062 bb = bb_copy->flags & BB_DUPLICATED ? get_bb_original (bb_copy) : bb_copy;
5064 if (e_copy->dest->flags & BB_DUPLICATED)
5065 dest = get_bb_original (e_copy->dest);
5067 dest = e_copy->dest;
5069 e = find_edge (bb, dest);
5072 /* During loop unrolling the target of the latch edge is copied.
5073 In this case we are not looking for edge to dest, but to
5074 duplicated block whose original was dest. */
5075 FOR_EACH_EDGE (e, ei, bb->succs)
5077 if ((e->dest->flags & BB_DUPLICATED)
5078 && get_bb_original (e->dest) == dest)
5082 gcc_assert (e != NULL);
5085 for (psi = gsi_start_phis (e->dest),
5086 psi_copy = gsi_start_phis (e_copy->dest);
5088 gsi_next (&psi), gsi_next (&psi_copy))
5090 phi = gsi_stmt (psi);
5091 phi_copy = gsi_stmt (psi_copy);
5092 def = PHI_ARG_DEF_FROM_EDGE (phi, e);
5093 add_phi_arg (phi_copy, def, e_copy);
5098 /* Basic block BB_COPY was created by code duplication. Add phi node
5099 arguments for edges going out of BB_COPY. The blocks that were
5100 duplicated have BB_DUPLICATED set. */
5103 add_phi_args_after_copy_bb (basic_block bb_copy)
5108 FOR_EACH_EDGE (e_copy, ei, bb_copy->succs)
5110 add_phi_args_after_copy_edge (e_copy);
5114 /* Blocks in REGION_COPY array of length N_REGION were created by
5115 duplication of basic blocks. Add phi node arguments for edges
5116 going from these blocks. If E_COPY is not NULL, also add
5117 phi node arguments for its destination.*/
5120 add_phi_args_after_copy (basic_block *region_copy, unsigned n_region,
5125 for (i = 0; i < n_region; i++)
5126 region_copy[i]->flags |= BB_DUPLICATED;
5128 for (i = 0; i < n_region; i++)
5129 add_phi_args_after_copy_bb (region_copy[i]);
5131 add_phi_args_after_copy_edge (e_copy);
5133 for (i = 0; i < n_region; i++)
5134 region_copy[i]->flags &= ~BB_DUPLICATED;
5137 /* Duplicates a REGION (set of N_REGION basic blocks) with just a single
5138 important exit edge EXIT. By important we mean that no SSA name defined
5139 inside region is live over the other exit edges of the region. All entry
5140 edges to the region must go to ENTRY->dest. The edge ENTRY is redirected
5141 to the duplicate of the region. SSA form, dominance and loop information
5142 is updated. The new basic blocks are stored to REGION_COPY in the same
5143 order as they had in REGION, provided that REGION_COPY is not NULL.
5144 The function returns false if it is unable to copy the region,
5148 gimple_duplicate_sese_region (edge entry, edge exit,
5149 basic_block *region, unsigned n_region,
5150 basic_block *region_copy)
5153 bool free_region_copy = false, copying_header = false;
5154 struct loop *loop = entry->dest->loop_father;
5156 VEC (basic_block, heap) *doms;
5158 int total_freq = 0, entry_freq = 0;
5159 gcov_type total_count = 0, entry_count = 0;
5161 if (!can_copy_bbs_p (region, n_region))
5164 /* Some sanity checking. Note that we do not check for all possible
5165 missuses of the functions. I.e. if you ask to copy something weird,
5166 it will work, but the state of structures probably will not be
5168 for (i = 0; i < n_region; i++)
5170 /* We do not handle subloops, i.e. all the blocks must belong to the
5172 if (region[i]->loop_father != loop)
5175 if (region[i] != entry->dest
5176 && region[i] == loop->header)
5180 set_loop_copy (loop, loop);
5182 /* In case the function is used for loop header copying (which is the primary
5183 use), ensure that EXIT and its copy will be new latch and entry edges. */
5184 if (loop->header == entry->dest)
5186 copying_header = true;
5187 set_loop_copy (loop, loop_outer (loop));
5189 if (!dominated_by_p (CDI_DOMINATORS, loop->latch, exit->src))
5192 for (i = 0; i < n_region; i++)
5193 if (region[i] != exit->src
5194 && dominated_by_p (CDI_DOMINATORS, region[i], exit->src))
5200 region_copy = XNEWVEC (basic_block, n_region);
5201 free_region_copy = true;
5204 gcc_assert (!need_ssa_update_p (cfun));
5206 /* Record blocks outside the region that are dominated by something
5209 initialize_original_copy_tables ();
5211 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5213 if (entry->dest->count)
5215 total_count = entry->dest->count;
5216 entry_count = entry->count;
5217 /* Fix up corner cases, to avoid division by zero or creation of negative
5219 if (entry_count > total_count)
5220 entry_count = total_count;
5224 total_freq = entry->dest->frequency;
5225 entry_freq = EDGE_FREQUENCY (entry);
5226 /* Fix up corner cases, to avoid division by zero or creation of negative
5228 if (total_freq == 0)
5230 else if (entry_freq > total_freq)
5231 entry_freq = total_freq;
5234 copy_bbs (region, n_region, region_copy, &exit, 1, &exit_copy, loop,
5235 split_edge_bb_loc (entry));
5238 scale_bbs_frequencies_gcov_type (region, n_region,
5239 total_count - entry_count,
5241 scale_bbs_frequencies_gcov_type (region_copy, n_region, entry_count,
5246 scale_bbs_frequencies_int (region, n_region, total_freq - entry_freq,
5248 scale_bbs_frequencies_int (region_copy, n_region, entry_freq, total_freq);
5253 loop->header = exit->dest;
5254 loop->latch = exit->src;
5257 /* Redirect the entry and add the phi node arguments. */
5258 redirected = redirect_edge_and_branch (entry, get_bb_copy (entry->dest));
5259 gcc_assert (redirected != NULL);
5260 flush_pending_stmts (entry);
5262 /* Concerning updating of dominators: We must recount dominators
5263 for entry block and its copy. Anything that is outside of the
5264 region, but was dominated by something inside needs recounting as
5266 set_immediate_dominator (CDI_DOMINATORS, entry->dest, entry->src);
5267 VEC_safe_push (basic_block, heap, doms, get_bb_original (entry->dest));
5268 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5269 VEC_free (basic_block, heap, doms);
5271 /* Add the other PHI node arguments. */
5272 add_phi_args_after_copy (region_copy, n_region, NULL);
5274 /* Update the SSA web. */
5275 update_ssa (TODO_update_ssa);
5277 if (free_region_copy)
5280 free_original_copy_tables ();
5284 /* Duplicates REGION consisting of N_REGION blocks. The new blocks
5285 are stored to REGION_COPY in the same order in that they appear
5286 in REGION, if REGION_COPY is not NULL. ENTRY is the entry to
5287 the region, EXIT an exit from it. The condition guarding EXIT
5288 is moved to ENTRY. Returns true if duplication succeeds, false
5314 gimple_duplicate_sese_tail (edge entry ATTRIBUTE_UNUSED, edge exit ATTRIBUTE_UNUSED,
5315 basic_block *region ATTRIBUTE_UNUSED, unsigned n_region ATTRIBUTE_UNUSED,
5316 basic_block *region_copy ATTRIBUTE_UNUSED)
5319 bool free_region_copy = false;
5320 struct loop *loop = exit->dest->loop_father;
5321 struct loop *orig_loop = entry->dest->loop_father;
5322 basic_block switch_bb, entry_bb, nentry_bb;
5323 VEC (basic_block, heap) *doms;
5324 int total_freq = 0, exit_freq = 0;
5325 gcov_type total_count = 0, exit_count = 0;
5326 edge exits[2], nexits[2], e;
5327 gimple_stmt_iterator gsi;
5331 gcc_assert (EDGE_COUNT (exit->src->succs) == 2);
5333 exits[1] = EDGE_SUCC (exit->src, EDGE_SUCC (exit->src, 0) == exit);
5335 if (!can_copy_bbs_p (region, n_region))
5338 /* Some sanity checking. Note that we do not check for all possible
5339 missuses of the functions. I.e. if you ask to copy something weird
5340 (e.g., in the example, if there is a jump from inside to the middle
5341 of some_code, or come_code defines some of the values used in cond)
5342 it will work, but the resulting code will not be correct. */
5343 for (i = 0; i < n_region; i++)
5345 /* We do not handle subloops, i.e. all the blocks must belong to the
5347 if (region[i]->loop_father != orig_loop)
5350 if (region[i] == orig_loop->latch)
5354 initialize_original_copy_tables ();
5355 set_loop_copy (orig_loop, loop);
5359 region_copy = XNEWVEC (basic_block, n_region);
5360 free_region_copy = true;
5363 gcc_assert (!need_ssa_update_p (cfun));
5365 /* Record blocks outside the region that are dominated by something
5367 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5369 if (exit->src->count)
5371 total_count = exit->src->count;
5372 exit_count = exit->count;
5373 /* Fix up corner cases, to avoid division by zero or creation of negative
5375 if (exit_count > total_count)
5376 exit_count = total_count;
5380 total_freq = exit->src->frequency;
5381 exit_freq = EDGE_FREQUENCY (exit);
5382 /* Fix up corner cases, to avoid division by zero or creation of negative
5384 if (total_freq == 0)
5386 if (exit_freq > total_freq)
5387 exit_freq = total_freq;
5390 copy_bbs (region, n_region, region_copy, exits, 2, nexits, orig_loop,
5391 split_edge_bb_loc (exit));
5394 scale_bbs_frequencies_gcov_type (region, n_region,
5395 total_count - exit_count,
5397 scale_bbs_frequencies_gcov_type (region_copy, n_region, exit_count,
5402 scale_bbs_frequencies_int (region, n_region, total_freq - exit_freq,
5404 scale_bbs_frequencies_int (region_copy, n_region, exit_freq, total_freq);
5407 /* Create the switch block, and put the exit condition to it. */
5408 entry_bb = entry->dest;
5409 nentry_bb = get_bb_copy (entry_bb);
5410 if (!last_stmt (entry->src)
5411 || !stmt_ends_bb_p (last_stmt (entry->src)))
5412 switch_bb = entry->src;
5414 switch_bb = split_edge (entry);
5415 set_immediate_dominator (CDI_DOMINATORS, nentry_bb, switch_bb);
5417 gsi = gsi_last_bb (switch_bb);
5418 cond_stmt = last_stmt (exit->src);
5419 gcc_assert (gimple_code (cond_stmt) == GIMPLE_COND);
5420 cond_stmt = gimple_copy (cond_stmt);
5421 gimple_cond_set_lhs (cond_stmt, unshare_expr (gimple_cond_lhs (cond_stmt)));
5422 gimple_cond_set_rhs (cond_stmt, unshare_expr (gimple_cond_rhs (cond_stmt)));
5423 gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT);
5425 sorig = single_succ_edge (switch_bb);
5426 sorig->flags = exits[1]->flags;
5427 snew = make_edge (switch_bb, nentry_bb, exits[0]->flags);
5429 /* Register the new edge from SWITCH_BB in loop exit lists. */
5430 rescan_loop_exit (snew, true, false);
5432 /* Add the PHI node arguments. */
5433 add_phi_args_after_copy (region_copy, n_region, snew);
5435 /* Get rid of now superfluous conditions and associated edges (and phi node
5437 e = redirect_edge_and_branch (exits[0], exits[1]->dest);
5438 PENDING_STMT (e) = NULL;
5439 e = redirect_edge_and_branch (nexits[1], nexits[0]->dest);
5440 PENDING_STMT (e) = NULL;
5442 /* Anything that is outside of the region, but was dominated by something
5443 inside needs to update dominance info. */
5444 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5445 VEC_free (basic_block, heap, doms);
5447 /* Update the SSA web. */
5448 update_ssa (TODO_update_ssa);
5450 if (free_region_copy)
5453 free_original_copy_tables ();
5457 /* Add all the blocks dominated by ENTRY to the array BBS_P. Stop
5458 adding blocks when the dominator traversal reaches EXIT. This
5459 function silently assumes that ENTRY strictly dominates EXIT. */
5462 gather_blocks_in_sese_region (basic_block entry, basic_block exit,
5463 VEC(basic_block,heap) **bbs_p)
5467 for (son = first_dom_son (CDI_DOMINATORS, entry);
5469 son = next_dom_son (CDI_DOMINATORS, son))
5471 VEC_safe_push (basic_block, heap, *bbs_p, son);
5473 gather_blocks_in_sese_region (son, exit, bbs_p);
5477 /* Replaces *TP with a duplicate (belonging to function TO_CONTEXT).
5478 The duplicates are recorded in VARS_MAP. */
5481 replace_by_duplicate_decl (tree *tp, struct pointer_map_t *vars_map,
5484 tree t = *tp, new_t;
5485 struct function *f = DECL_STRUCT_FUNCTION (to_context);
5488 if (DECL_CONTEXT (t) == to_context)
5491 loc = pointer_map_contains (vars_map, t);
5495 loc = pointer_map_insert (vars_map, t);
5499 new_t = copy_var_decl (t, DECL_NAME (t), TREE_TYPE (t));
5500 f->local_decls = tree_cons (NULL_TREE, new_t, f->local_decls);
5504 gcc_assert (TREE_CODE (t) == CONST_DECL);
5505 new_t = copy_node (t);
5507 DECL_CONTEXT (new_t) = to_context;
5512 new_t = (tree) *loc;
5518 /* Creates an ssa name in TO_CONTEXT equivalent to NAME.
5519 VARS_MAP maps old ssa names and var_decls to the new ones. */
5522 replace_ssa_name (tree name, struct pointer_map_t *vars_map,
5526 tree new_name, decl = SSA_NAME_VAR (name);
5528 gcc_assert (is_gimple_reg (name));
5530 loc = pointer_map_contains (vars_map, name);
5534 replace_by_duplicate_decl (&decl, vars_map, to_context);
5536 push_cfun (DECL_STRUCT_FUNCTION (to_context));
5537 if (gimple_in_ssa_p (cfun))
5538 add_referenced_var (decl);
5540 new_name = make_ssa_name (decl, SSA_NAME_DEF_STMT (name));
5541 if (SSA_NAME_IS_DEFAULT_DEF (name))
5542 set_default_def (decl, new_name);
5545 loc = pointer_map_insert (vars_map, name);
5549 new_name = (tree) *loc;
5560 struct pointer_map_t *vars_map;
5561 htab_t new_label_map;
5565 /* Helper for move_block_to_fn. Set TREE_BLOCK in every expression
5566 contained in *TP if it has been ORIG_BLOCK previously and change the
5567 DECL_CONTEXT of every local variable referenced in *TP. */
5570 move_stmt_op (tree *tp, int *walk_subtrees, void *data)
5572 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
5573 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5577 /* We should never have TREE_BLOCK set on non-statements. */
5578 gcc_assert (!TREE_BLOCK (t));
5580 else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
5582 if (TREE_CODE (t) == SSA_NAME)
5583 *tp = replace_ssa_name (t, p->vars_map, p->to_context);
5584 else if (TREE_CODE (t) == LABEL_DECL)
5586 if (p->new_label_map)
5588 struct tree_map in, *out;
5590 out = (struct tree_map *)
5591 htab_find_with_hash (p->new_label_map, &in, DECL_UID (t));
5596 DECL_CONTEXT (t) = p->to_context;
5598 else if (p->remap_decls_p)
5600 /* Replace T with its duplicate. T should no longer appear in the
5601 parent function, so this looks wasteful; however, it may appear
5602 in referenced_vars, and more importantly, as virtual operands of
5603 statements, and in alias lists of other variables. It would be
5604 quite difficult to expunge it from all those places. ??? It might
5605 suffice to do this for addressable variables. */
5606 if ((TREE_CODE (t) == VAR_DECL
5607 && !is_global_var (t))
5608 || TREE_CODE (t) == CONST_DECL)
5609 replace_by_duplicate_decl (tp, p->vars_map, p->to_context);
5612 && gimple_in_ssa_p (cfun))
5614 push_cfun (DECL_STRUCT_FUNCTION (p->to_context));
5615 add_referenced_var (*tp);
5621 else if (TYPE_P (t))
5627 /* Like move_stmt_op, but for gimple statements.
5629 Helper for move_block_to_fn. Set GIMPLE_BLOCK in every expression
5630 contained in the current statement in *GSI_P and change the
5631 DECL_CONTEXT of every local variable referenced in the current
5635 move_stmt_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
5636 struct walk_stmt_info *wi)
5638 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5639 gimple stmt = gsi_stmt (*gsi_p);
5640 tree block = gimple_block (stmt);
5642 if (p->orig_block == NULL_TREE
5643 || block == p->orig_block
5644 || block == NULL_TREE)
5645 gimple_set_block (stmt, p->new_block);
5646 #ifdef ENABLE_CHECKING
5647 else if (block != p->new_block)
5649 while (block && block != p->orig_block)
5650 block = BLOCK_SUPERCONTEXT (block);
5655 if (is_gimple_omp (stmt)
5656 && gimple_code (stmt) != GIMPLE_OMP_RETURN
5657 && gimple_code (stmt) != GIMPLE_OMP_CONTINUE)
5659 /* Do not remap variables inside OMP directives. Variables
5660 referenced in clauses and directive header belong to the
5661 parent function and should not be moved into the child
5663 bool save_remap_decls_p = p->remap_decls_p;
5664 p->remap_decls_p = false;
5665 *handled_ops_p = true;
5667 walk_gimple_seq (gimple_omp_body (stmt), move_stmt_r, move_stmt_op, wi);
5669 p->remap_decls_p = save_remap_decls_p;
5675 /* Marks virtual operands of all statements in basic blocks BBS for
5679 mark_virtual_ops_in_bb (basic_block bb)
5681 gimple_stmt_iterator gsi;
5683 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5684 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5686 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5687 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5690 /* Move basic block BB from function CFUN to function DEST_FN. The
5691 block is moved out of the original linked list and placed after
5692 block AFTER in the new list. Also, the block is removed from the
5693 original array of blocks and placed in DEST_FN's array of blocks.
5694 If UPDATE_EDGE_COUNT_P is true, the edge counts on both CFGs is
5695 updated to reflect the moved edges.
5697 The local variables are remapped to new instances, VARS_MAP is used
5698 to record the mapping. */
5701 move_block_to_fn (struct function *dest_cfun, basic_block bb,
5702 basic_block after, bool update_edge_count_p,
5703 struct move_stmt_d *d, int eh_offset)
5705 struct control_flow_graph *cfg;
5708 gimple_stmt_iterator si;
5709 unsigned old_len, new_len;
5711 /* Remove BB from dominance structures. */
5712 delete_from_dominance_info (CDI_DOMINATORS, bb);
5714 remove_bb_from_loops (bb);
5716 /* Link BB to the new linked list. */
5717 move_block_after (bb, after);
5719 /* Update the edge count in the corresponding flowgraphs. */
5720 if (update_edge_count_p)
5721 FOR_EACH_EDGE (e, ei, bb->succs)
5723 cfun->cfg->x_n_edges--;
5724 dest_cfun->cfg->x_n_edges++;
5727 /* Remove BB from the original basic block array. */
5728 VEC_replace (basic_block, cfun->cfg->x_basic_block_info, bb->index, NULL);
5729 cfun->cfg->x_n_basic_blocks--;
5731 /* Grow DEST_CFUN's basic block array if needed. */
5732 cfg = dest_cfun->cfg;
5733 cfg->x_n_basic_blocks++;
5734 if (bb->index >= cfg->x_last_basic_block)
5735 cfg->x_last_basic_block = bb->index + 1;
5737 old_len = VEC_length (basic_block, cfg->x_basic_block_info);
5738 if ((unsigned) cfg->x_last_basic_block >= old_len)
5740 new_len = cfg->x_last_basic_block + (cfg->x_last_basic_block + 3) / 4;
5741 VEC_safe_grow_cleared (basic_block, gc, cfg->x_basic_block_info,
5745 VEC_replace (basic_block, cfg->x_basic_block_info,
5748 /* Remap the variables in phi nodes. */
5749 for (si = gsi_start_phis (bb); !gsi_end_p (si); )
5751 gimple phi = gsi_stmt (si);
5753 tree op = PHI_RESULT (phi);
5756 if (!is_gimple_reg (op))
5758 /* Remove the phi nodes for virtual operands (alias analysis will be
5759 run for the new function, anyway). */
5760 remove_phi_node (&si, true);
5764 SET_PHI_RESULT (phi,
5765 replace_ssa_name (op, d->vars_map, dest_cfun->decl));
5766 FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
5768 op = USE_FROM_PTR (use);
5769 if (TREE_CODE (op) == SSA_NAME)
5770 SET_USE (use, replace_ssa_name (op, d->vars_map, dest_cfun->decl));
5776 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
5778 gimple stmt = gsi_stmt (si);
5780 struct walk_stmt_info wi;
5782 memset (&wi, 0, sizeof (wi));
5784 walk_gimple_stmt (&si, move_stmt_r, move_stmt_op, &wi);
5786 if (gimple_code (stmt) == GIMPLE_LABEL)
5788 tree label = gimple_label_label (stmt);
5789 int uid = LABEL_DECL_UID (label);
5791 gcc_assert (uid > -1);
5793 old_len = VEC_length (basic_block, cfg->x_label_to_block_map);
5794 if (old_len <= (unsigned) uid)
5796 new_len = 3 * uid / 2 + 1;
5797 VEC_safe_grow_cleared (basic_block, gc,
5798 cfg->x_label_to_block_map, new_len);
5801 VEC_replace (basic_block, cfg->x_label_to_block_map, uid, bb);
5802 VEC_replace (basic_block, cfun->cfg->x_label_to_block_map, uid, NULL);
5804 gcc_assert (DECL_CONTEXT (label) == dest_cfun->decl);
5806 if (uid >= dest_cfun->cfg->last_label_uid)
5807 dest_cfun->cfg->last_label_uid = uid + 1;
5809 else if (gimple_code (stmt) == GIMPLE_RESX && eh_offset != 0)
5810 gimple_resx_set_region (stmt, gimple_resx_region (stmt) + eh_offset);
5812 region = lookup_stmt_eh_region (stmt);
5815 add_stmt_to_eh_region_fn (dest_cfun, stmt, region + eh_offset);
5816 remove_stmt_from_eh_region (stmt);
5817 gimple_duplicate_stmt_histograms (dest_cfun, stmt, cfun, stmt);
5818 gimple_remove_stmt_histograms (cfun, stmt);
5821 /* We cannot leave any operands allocated from the operand caches of
5822 the current function. */
5823 free_stmt_operands (stmt);
5824 push_cfun (dest_cfun);
5829 FOR_EACH_EDGE (e, ei, bb->succs)
5832 tree block = e->goto_block;
5833 if (d->orig_block == NULL_TREE
5834 || block == d->orig_block)
5835 e->goto_block = d->new_block;
5836 #ifdef ENABLE_CHECKING
5837 else if (block != d->new_block)
5839 while (block && block != d->orig_block)
5840 block = BLOCK_SUPERCONTEXT (block);
5847 /* Examine the statements in BB (which is in SRC_CFUN); find and return
5848 the outermost EH region. Use REGION as the incoming base EH region. */
5851 find_outermost_region_in_block (struct function *src_cfun,
5852 basic_block bb, int region)
5854 gimple_stmt_iterator si;
5856 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
5858 gimple stmt = gsi_stmt (si);
5861 if (gimple_code (stmt) == GIMPLE_RESX)
5862 stmt_region = gimple_resx_region (stmt);
5864 stmt_region = lookup_stmt_eh_region_fn (src_cfun, stmt);
5865 if (stmt_region > 0)
5868 region = stmt_region;
5869 else if (stmt_region != region)
5871 region = eh_region_outermost (src_cfun, stmt_region, region);
5872 gcc_assert (region != -1);
5881 new_label_mapper (tree decl, void *data)
5883 htab_t hash = (htab_t) data;
5887 gcc_assert (TREE_CODE (decl) == LABEL_DECL);
5889 m = XNEW (struct tree_map);
5890 m->hash = DECL_UID (decl);
5891 m->base.from = decl;
5892 m->to = create_artificial_label ();
5893 LABEL_DECL_UID (m->to) = LABEL_DECL_UID (decl);
5894 if (LABEL_DECL_UID (m->to) >= cfun->cfg->last_label_uid)
5895 cfun->cfg->last_label_uid = LABEL_DECL_UID (m->to) + 1;
5897 slot = htab_find_slot_with_hash (hash, m, m->hash, INSERT);
5898 gcc_assert (*slot == NULL);
5905 /* Change DECL_CONTEXT of all BLOCK_VARS in block, including
5909 replace_block_vars_by_duplicates (tree block, struct pointer_map_t *vars_map,
5914 for (tp = &BLOCK_VARS (block); *tp; tp = &TREE_CHAIN (*tp))
5917 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != CONST_DECL)
5919 replace_by_duplicate_decl (&t, vars_map, to_context);
5922 if (TREE_CODE (*tp) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (*tp))
5924 SET_DECL_VALUE_EXPR (t, DECL_VALUE_EXPR (*tp));
5925 DECL_HAS_VALUE_EXPR_P (t) = 1;
5927 TREE_CHAIN (t) = TREE_CHAIN (*tp);
5932 for (block = BLOCK_SUBBLOCKS (block); block; block = BLOCK_CHAIN (block))
5933 replace_block_vars_by_duplicates (block, vars_map, to_context);
5936 /* Move a single-entry, single-exit region delimited by ENTRY_BB and
5937 EXIT_BB to function DEST_CFUN. The whole region is replaced by a
5938 single basic block in the original CFG and the new basic block is
5939 returned. DEST_CFUN must not have a CFG yet.
5941 Note that the region need not be a pure SESE region. Blocks inside
5942 the region may contain calls to abort/exit. The only restriction
5943 is that ENTRY_BB should be the only entry point and it must
5946 Change TREE_BLOCK of all statements in ORIG_BLOCK to the new
5947 functions outermost BLOCK, move all subblocks of ORIG_BLOCK
5948 to the new function.
5950 All local variables referenced in the region are assumed to be in
5951 the corresponding BLOCK_VARS and unexpanded variable lists
5952 associated with DEST_CFUN. */
5955 move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb,
5956 basic_block exit_bb, tree orig_block)
5958 VEC(basic_block,heap) *bbs, *dom_bbs;
5959 basic_block dom_entry = get_immediate_dominator (CDI_DOMINATORS, entry_bb);
5960 basic_block after, bb, *entry_pred, *exit_succ, abb;
5961 struct function *saved_cfun = cfun;
5962 int *entry_flag, *exit_flag, eh_offset;
5963 unsigned *entry_prob, *exit_prob;
5964 unsigned i, num_entry_edges, num_exit_edges;
5967 htab_t new_label_map;
5968 struct pointer_map_t *vars_map;
5969 struct loop *loop = entry_bb->loop_father;
5970 struct move_stmt_d d;
5972 /* If ENTRY does not strictly dominate EXIT, this cannot be an SESE
5974 gcc_assert (entry_bb != exit_bb
5976 || dominated_by_p (CDI_DOMINATORS, exit_bb, entry_bb)));
5978 /* Collect all the blocks in the region. Manually add ENTRY_BB
5979 because it won't be added by dfs_enumerate_from. */
5981 VEC_safe_push (basic_block, heap, bbs, entry_bb);
5982 gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs);
5984 /* The blocks that used to be dominated by something in BBS will now be
5985 dominated by the new block. */
5986 dom_bbs = get_dominated_by_region (CDI_DOMINATORS,
5987 VEC_address (basic_block, bbs),
5988 VEC_length (basic_block, bbs));
5990 /* Detach ENTRY_BB and EXIT_BB from CFUN->CFG. We need to remember
5991 the predecessor edges to ENTRY_BB and the successor edges to
5992 EXIT_BB so that we can re-attach them to the new basic block that
5993 will replace the region. */
5994 num_entry_edges = EDGE_COUNT (entry_bb->preds);
5995 entry_pred = (basic_block *) xcalloc (num_entry_edges, sizeof (basic_block));
5996 entry_flag = (int *) xcalloc (num_entry_edges, sizeof (int));
5997 entry_prob = XNEWVEC (unsigned, num_entry_edges);
5999 for (ei = ei_start (entry_bb->preds); (e = ei_safe_edge (ei)) != NULL;)
6001 entry_prob[i] = e->probability;
6002 entry_flag[i] = e->flags;
6003 entry_pred[i++] = e->src;
6009 num_exit_edges = EDGE_COUNT (exit_bb->succs);
6010 exit_succ = (basic_block *) xcalloc (num_exit_edges,
6011 sizeof (basic_block));
6012 exit_flag = (int *) xcalloc (num_exit_edges, sizeof (int));
6013 exit_prob = XNEWVEC (unsigned, num_exit_edges);
6015 for (ei = ei_start (exit_bb->succs); (e = ei_safe_edge (ei)) != NULL;)
6017 exit_prob[i] = e->probability;
6018 exit_flag[i] = e->flags;
6019 exit_succ[i++] = e->dest;
6031 /* Switch context to the child function to initialize DEST_FN's CFG. */
6032 gcc_assert (dest_cfun->cfg == NULL);
6033 push_cfun (dest_cfun);
6035 init_empty_tree_cfg ();
6037 /* Initialize EH information for the new function. */
6039 new_label_map = NULL;
6044 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6045 region = find_outermost_region_in_block (saved_cfun, bb, region);
6047 init_eh_for_function ();
6050 new_label_map = htab_create (17, tree_map_hash, tree_map_eq, free);
6051 eh_offset = duplicate_eh_regions (saved_cfun, new_label_mapper,
6052 new_label_map, region, 0);
6058 /* Move blocks from BBS into DEST_CFUN. */
6059 gcc_assert (VEC_length (basic_block, bbs) >= 2);
6060 after = dest_cfun->cfg->x_entry_block_ptr;
6061 vars_map = pointer_map_create ();
6063 memset (&d, 0, sizeof (d));
6064 d.vars_map = vars_map;
6065 d.from_context = cfun->decl;
6066 d.to_context = dest_cfun->decl;
6067 d.new_label_map = new_label_map;
6068 d.remap_decls_p = true;
6069 d.orig_block = orig_block;
6070 d.new_block = DECL_INITIAL (dest_cfun->decl);
6072 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6074 /* No need to update edge counts on the last block. It has
6075 already been updated earlier when we detached the region from
6076 the original CFG. */
6077 move_block_to_fn (dest_cfun, bb, after, bb != exit_bb, &d, eh_offset);
6081 /* Rewire BLOCK_SUBBLOCKS of orig_block. */
6085 gcc_assert (BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6087 BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6088 = BLOCK_SUBBLOCKS (orig_block);
6089 for (block = BLOCK_SUBBLOCKS (orig_block);
6090 block; block = BLOCK_CHAIN (block))
6091 BLOCK_SUPERCONTEXT (block) = DECL_INITIAL (dest_cfun->decl);
6092 BLOCK_SUBBLOCKS (orig_block) = NULL_TREE;
6095 replace_block_vars_by_duplicates (DECL_INITIAL (dest_cfun->decl),
6096 vars_map, dest_cfun->decl);
6099 htab_delete (new_label_map);
6100 pointer_map_destroy (vars_map);
6102 /* Rewire the entry and exit blocks. The successor to the entry
6103 block turns into the successor of DEST_FN's ENTRY_BLOCK_PTR in
6104 the child function. Similarly, the predecessor of DEST_FN's
6105 EXIT_BLOCK_PTR turns into the predecessor of EXIT_BLOCK_PTR. We
6106 need to switch CFUN between DEST_CFUN and SAVED_CFUN so that the
6107 various CFG manipulation function get to the right CFG.
6109 FIXME, this is silly. The CFG ought to become a parameter to
6111 push_cfun (dest_cfun);
6112 make_edge (ENTRY_BLOCK_PTR, entry_bb, EDGE_FALLTHRU);
6114 make_edge (exit_bb, EXIT_BLOCK_PTR, 0);
6117 /* Back in the original function, the SESE region has disappeared,
6118 create a new basic block in its place. */
6119 bb = create_empty_bb (entry_pred[0]);
6121 add_bb_to_loop (bb, loop);
6122 for (i = 0; i < num_entry_edges; i++)
6124 e = make_edge (entry_pred[i], bb, entry_flag[i]);
6125 e->probability = entry_prob[i];
6128 for (i = 0; i < num_exit_edges; i++)
6130 e = make_edge (bb, exit_succ[i], exit_flag[i]);
6131 e->probability = exit_prob[i];
6134 set_immediate_dominator (CDI_DOMINATORS, bb, dom_entry);
6135 for (i = 0; VEC_iterate (basic_block, dom_bbs, i, abb); i++)
6136 set_immediate_dominator (CDI_DOMINATORS, abb, bb);
6137 VEC_free (basic_block, heap, dom_bbs);
6148 VEC_free (basic_block, heap, bbs);
6154 /* Dump FUNCTION_DECL FN to file FILE using FLAGS (see TDF_* in tree-pass.h)
6158 dump_function_to_file (tree fn, FILE *file, int flags)
6160 tree arg, vars, var;
6161 struct function *dsf;
6162 bool ignore_topmost_bind = false, any_var = false;
6166 fprintf (file, "%s (", lang_hooks.decl_printable_name (fn, 2));
6168 arg = DECL_ARGUMENTS (fn);
6171 print_generic_expr (file, TREE_TYPE (arg), dump_flags);
6172 fprintf (file, " ");
6173 print_generic_expr (file, arg, dump_flags);
6174 if (flags & TDF_VERBOSE)
6175 print_node (file, "", arg, 4);
6176 if (TREE_CHAIN (arg))
6177 fprintf (file, ", ");
6178 arg = TREE_CHAIN (arg);
6180 fprintf (file, ")\n");
6182 if (flags & TDF_VERBOSE)
6183 print_node (file, "", fn, 2);
6185 dsf = DECL_STRUCT_FUNCTION (fn);
6186 if (dsf && (flags & TDF_DETAILS))
6187 dump_eh_tree (file, dsf);
6189 if (flags & TDF_RAW && !gimple_has_body_p (fn))
6191 dump_node (fn, TDF_SLIM | flags, file);
6195 /* Switch CFUN to point to FN. */
6196 push_cfun (DECL_STRUCT_FUNCTION (fn));
6198 /* When GIMPLE is lowered, the variables are no longer available in
6199 BIND_EXPRs, so display them separately. */
6200 if (cfun && cfun->decl == fn && cfun->local_decls)
6202 ignore_topmost_bind = true;
6204 fprintf (file, "{\n");
6205 for (vars = cfun->local_decls; vars; vars = TREE_CHAIN (vars))
6207 var = TREE_VALUE (vars);
6209 print_generic_decl (file, var, flags);
6210 if (flags & TDF_VERBOSE)
6211 print_node (file, "", var, 4);
6212 fprintf (file, "\n");
6218 if (cfun && cfun->decl == fn && cfun->cfg && basic_block_info)
6220 /* If the CFG has been built, emit a CFG-based dump. */
6221 check_bb_profile (ENTRY_BLOCK_PTR, file);
6222 if (!ignore_topmost_bind)
6223 fprintf (file, "{\n");
6225 if (any_var && n_basic_blocks)
6226 fprintf (file, "\n");
6229 gimple_dump_bb (bb, file, 2, flags);
6231 fprintf (file, "}\n");
6232 check_bb_profile (EXIT_BLOCK_PTR, file);
6234 else if (DECL_SAVED_TREE (fn) == NULL)
6236 /* The function is now in GIMPLE form but the CFG has not been
6237 built yet. Emit the single sequence of GIMPLE statements
6238 that make up its body. */
6239 gimple_seq body = gimple_body (fn);
6241 if (gimple_seq_first_stmt (body)
6242 && gimple_seq_first_stmt (body) == gimple_seq_last_stmt (body)
6243 && gimple_code (gimple_seq_first_stmt (body)) == GIMPLE_BIND)
6244 print_gimple_seq (file, body, 0, flags);
6247 if (!ignore_topmost_bind)
6248 fprintf (file, "{\n");
6251 fprintf (file, "\n");
6253 print_gimple_seq (file, body, 2, flags);
6254 fprintf (file, "}\n");
6261 /* Make a tree based dump. */
6262 chain = DECL_SAVED_TREE (fn);
6264 if (chain && TREE_CODE (chain) == BIND_EXPR)
6266 if (ignore_topmost_bind)
6268 chain = BIND_EXPR_BODY (chain);
6276 if (!ignore_topmost_bind)
6277 fprintf (file, "{\n");
6282 fprintf (file, "\n");
6284 print_generic_stmt_indented (file, chain, flags, indent);
6285 if (ignore_topmost_bind)
6286 fprintf (file, "}\n");
6289 fprintf (file, "\n\n");
6296 /* Dump FUNCTION_DECL FN to stderr using FLAGS (see TDF_* in tree.h) */
6299 debug_function (tree fn, int flags)
6301 dump_function_to_file (fn, stderr, flags);
6305 /* Print on FILE the indexes for the predecessors of basic_block BB. */
6308 print_pred_bbs (FILE *file, basic_block bb)
6313 FOR_EACH_EDGE (e, ei, bb->preds)
6314 fprintf (file, "bb_%d ", e->src->index);
6318 /* Print on FILE the indexes for the successors of basic_block BB. */
6321 print_succ_bbs (FILE *file, basic_block bb)
6326 FOR_EACH_EDGE (e, ei, bb->succs)
6327 fprintf (file, "bb_%d ", e->dest->index);
6330 /* Print to FILE the basic block BB following the VERBOSITY level. */
6333 print_loops_bb (FILE *file, basic_block bb, int indent, int verbosity)
6335 char *s_indent = (char *) alloca ((size_t) indent + 1);
6336 memset ((void *) s_indent, ' ', (size_t) indent);
6337 s_indent[indent] = '\0';
6339 /* Print basic_block's header. */
6342 fprintf (file, "%s bb_%d (preds = {", s_indent, bb->index);
6343 print_pred_bbs (file, bb);
6344 fprintf (file, "}, succs = {");
6345 print_succ_bbs (file, bb);
6346 fprintf (file, "})\n");
6349 /* Print basic_block's body. */
6352 fprintf (file, "%s {\n", s_indent);
6353 gimple_dump_bb (bb, file, indent + 4, TDF_VOPS|TDF_MEMSYMS);
6354 fprintf (file, "%s }\n", s_indent);
6358 static void print_loop_and_siblings (FILE *, struct loop *, int, int);
6360 /* Pretty print LOOP on FILE, indented INDENT spaces. Following
6361 VERBOSITY level this outputs the contents of the loop, or just its
6365 print_loop (FILE *file, struct loop *loop, int indent, int verbosity)
6373 s_indent = (char *) alloca ((size_t) indent + 1);
6374 memset ((void *) s_indent, ' ', (size_t) indent);
6375 s_indent[indent] = '\0';
6377 /* Print loop's header. */
6378 fprintf (file, "%sloop_%d (header = %d, latch = %d", s_indent,
6379 loop->num, loop->header->index, loop->latch->index);
6380 fprintf (file, ", niter = ");
6381 print_generic_expr (file, loop->nb_iterations, 0);
6383 if (loop->any_upper_bound)
6385 fprintf (file, ", upper_bound = ");
6386 dump_double_int (file, loop->nb_iterations_upper_bound, true);
6389 if (loop->any_estimate)
6391 fprintf (file, ", estimate = ");
6392 dump_double_int (file, loop->nb_iterations_estimate, true);
6394 fprintf (file, ")\n");
6396 /* Print loop's body. */
6399 fprintf (file, "%s{\n", s_indent);
6401 if (bb->loop_father == loop)
6402 print_loops_bb (file, bb, indent, verbosity);
6404 print_loop_and_siblings (file, loop->inner, indent + 2, verbosity);
6405 fprintf (file, "%s}\n", s_indent);
6409 /* Print the LOOP and its sibling loops on FILE, indented INDENT
6410 spaces. Following VERBOSITY level this outputs the contents of the
6411 loop, or just its structure. */
6414 print_loop_and_siblings (FILE *file, struct loop *loop, int indent, int verbosity)
6419 print_loop (file, loop, indent, verbosity);
6420 print_loop_and_siblings (file, loop->next, indent, verbosity);
6423 /* Follow a CFG edge from the entry point of the program, and on entry
6424 of a loop, pretty print the loop structure on FILE. */
6427 print_loops (FILE *file, int verbosity)
6431 bb = ENTRY_BLOCK_PTR;
6432 if (bb && bb->loop_father)
6433 print_loop_and_siblings (file, bb->loop_father, 0, verbosity);
6437 /* Debugging loops structure at tree level, at some VERBOSITY level. */
6440 debug_loops (int verbosity)
6442 print_loops (stderr, verbosity);
6445 /* Print on stderr the code of LOOP, at some VERBOSITY level. */
6448 debug_loop (struct loop *loop, int verbosity)
6450 print_loop (stderr, loop, 0, verbosity);
6453 /* Print on stderr the code of loop number NUM, at some VERBOSITY
6457 debug_loop_num (unsigned num, int verbosity)
6459 debug_loop (get_loop (num), verbosity);
6462 /* Return true if BB ends with a call, possibly followed by some
6463 instructions that must stay with the call. Return false,
6467 gimple_block_ends_with_call_p (basic_block bb)
6469 gimple_stmt_iterator gsi = gsi_last_bb (bb);
6470 return is_gimple_call (gsi_stmt (gsi));
6474 /* Return true if BB ends with a conditional branch. Return false,
6478 gimple_block_ends_with_condjump_p (const_basic_block bb)
6480 gimple stmt = last_stmt (CONST_CAST_BB (bb));
6481 return (stmt && gimple_code (stmt) == GIMPLE_COND);
6485 /* Return true if we need to add fake edge to exit at statement T.
6486 Helper function for gimple_flow_call_edges_add. */
6489 need_fake_edge_p (gimple t)
6491 tree fndecl = NULL_TREE;
6494 /* NORETURN and LONGJMP calls already have an edge to exit.
6495 CONST and PURE calls do not need one.
6496 We don't currently check for CONST and PURE here, although
6497 it would be a good idea, because those attributes are
6498 figured out from the RTL in mark_constant_function, and
6499 the counter incrementation code from -fprofile-arcs
6500 leads to different results from -fbranch-probabilities. */
6501 if (is_gimple_call (t))
6503 fndecl = gimple_call_fndecl (t);
6504 call_flags = gimple_call_flags (t);
6507 if (is_gimple_call (t)
6509 && DECL_BUILT_IN (fndecl)
6510 && (call_flags & ECF_NOTHROW)
6511 && !(call_flags & ECF_RETURNS_TWICE)
6512 /* fork() doesn't really return twice, but the effect of
6513 wrapping it in __gcov_fork() which calls __gcov_flush()
6514 and clears the counters before forking has the same
6515 effect as returning twice. Force a fake edge. */
6516 && !(DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6517 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_FORK))
6520 if (is_gimple_call (t)
6521 && !(call_flags & ECF_NORETURN))
6524 if (gimple_code (t) == GIMPLE_ASM
6525 && (gimple_asm_volatile_p (t) || gimple_asm_input_p (t)))
6532 /* Add fake edges to the function exit for any non constant and non
6533 noreturn calls, volatile inline assembly in the bitmap of blocks
6534 specified by BLOCKS or to the whole CFG if BLOCKS is zero. Return
6535 the number of blocks that were split.
6537 The goal is to expose cases in which entering a basic block does
6538 not imply that all subsequent instructions must be executed. */
6541 gimple_flow_call_edges_add (sbitmap blocks)
6544 int blocks_split = 0;
6545 int last_bb = last_basic_block;
6546 bool check_last_block = false;
6548 if (n_basic_blocks == NUM_FIXED_BLOCKS)
6552 check_last_block = true;
6554 check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index);
6556 /* In the last basic block, before epilogue generation, there will be
6557 a fallthru edge to EXIT. Special care is required if the last insn
6558 of the last basic block is a call because make_edge folds duplicate
6559 edges, which would result in the fallthru edge also being marked
6560 fake, which would result in the fallthru edge being removed by
6561 remove_fake_edges, which would result in an invalid CFG.
6563 Moreover, we can't elide the outgoing fake edge, since the block
6564 profiler needs to take this into account in order to solve the minimal
6565 spanning tree in the case that the call doesn't return.
6567 Handle this by adding a dummy instruction in a new last basic block. */
6568 if (check_last_block)
6570 basic_block bb = EXIT_BLOCK_PTR->prev_bb;
6571 gimple_stmt_iterator gsi = gsi_last_bb (bb);
6574 if (!gsi_end_p (gsi))
6577 if (t && need_fake_edge_p (t))
6581 e = find_edge (bb, EXIT_BLOCK_PTR);
6584 gsi_insert_on_edge (e, gimple_build_nop ());
6585 gsi_commit_edge_inserts ();
6590 /* Now add fake edges to the function exit for any non constant
6591 calls since there is no way that we can determine if they will
6593 for (i = 0; i < last_bb; i++)
6595 basic_block bb = BASIC_BLOCK (i);
6596 gimple_stmt_iterator gsi;
6597 gimple stmt, last_stmt;
6602 if (blocks && !TEST_BIT (blocks, i))
6605 gsi = gsi_last_bb (bb);
6606 if (!gsi_end_p (gsi))
6608 last_stmt = gsi_stmt (gsi);
6611 stmt = gsi_stmt (gsi);
6612 if (need_fake_edge_p (stmt))
6616 /* The handling above of the final block before the
6617 epilogue should be enough to verify that there is
6618 no edge to the exit block in CFG already.
6619 Calling make_edge in such case would cause us to
6620 mark that edge as fake and remove it later. */
6621 #ifdef ENABLE_CHECKING
6622 if (stmt == last_stmt)
6624 e = find_edge (bb, EXIT_BLOCK_PTR);
6625 gcc_assert (e == NULL);
6629 /* Note that the following may create a new basic block
6630 and renumber the existing basic blocks. */
6631 if (stmt != last_stmt)
6633 e = split_block (bb, stmt);
6637 make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE);
6641 while (!gsi_end_p (gsi));
6646 verify_flow_info ();
6648 return blocks_split;
6651 /* Purge dead abnormal call edges from basic block BB. */
6654 gimple_purge_dead_abnormal_call_edges (basic_block bb)
6656 bool changed = gimple_purge_dead_eh_edges (bb);
6658 if (cfun->has_nonlocal_label)
6660 gimple stmt = last_stmt (bb);
6664 if (!(stmt && stmt_can_make_abnormal_goto (stmt)))
6665 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6667 if (e->flags & EDGE_ABNORMAL)
6676 /* See gimple_purge_dead_eh_edges below. */
6678 free_dominance_info (CDI_DOMINATORS);
6684 /* Removes edge E and all the blocks dominated by it, and updates dominance
6685 information. The IL in E->src needs to be updated separately.
6686 If dominance info is not available, only the edge E is removed.*/
6689 remove_edge_and_dominated_blocks (edge e)
6691 VEC (basic_block, heap) *bbs_to_remove = NULL;
6692 VEC (basic_block, heap) *bbs_to_fix_dom = NULL;
6696 bool none_removed = false;
6698 basic_block bb, dbb;
6701 if (!dom_info_available_p (CDI_DOMINATORS))
6707 /* No updating is needed for edges to exit. */
6708 if (e->dest == EXIT_BLOCK_PTR)
6710 if (cfgcleanup_altered_bbs)
6711 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6716 /* First, we find the basic blocks to remove. If E->dest has a predecessor
6717 that is not dominated by E->dest, then this set is empty. Otherwise,
6718 all the basic blocks dominated by E->dest are removed.
6720 Also, to DF_IDOM we store the immediate dominators of the blocks in
6721 the dominance frontier of E (i.e., of the successors of the
6722 removed blocks, if there are any, and of E->dest otherwise). */
6723 FOR_EACH_EDGE (f, ei, e->dest->preds)
6728 if (!dominated_by_p (CDI_DOMINATORS, f->src, e->dest))
6730 none_removed = true;
6735 df = BITMAP_ALLOC (NULL);
6736 df_idom = BITMAP_ALLOC (NULL);
6739 bitmap_set_bit (df_idom,
6740 get_immediate_dominator (CDI_DOMINATORS, e->dest)->index);
6743 bbs_to_remove = get_all_dominated_blocks (CDI_DOMINATORS, e->dest);
6744 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6746 FOR_EACH_EDGE (f, ei, bb->succs)
6748 if (f->dest != EXIT_BLOCK_PTR)
6749 bitmap_set_bit (df, f->dest->index);
6752 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6753 bitmap_clear_bit (df, bb->index);
6755 EXECUTE_IF_SET_IN_BITMAP (df, 0, i, bi)
6757 bb = BASIC_BLOCK (i);
6758 bitmap_set_bit (df_idom,
6759 get_immediate_dominator (CDI_DOMINATORS, bb)->index);
6763 if (cfgcleanup_altered_bbs)
6765 /* Record the set of the altered basic blocks. */
6766 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6767 bitmap_ior_into (cfgcleanup_altered_bbs, df);
6770 /* Remove E and the cancelled blocks. */
6775 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6776 delete_basic_block (bb);
6779 /* Update the dominance information. The immediate dominator may change only
6780 for blocks whose immediate dominator belongs to DF_IDOM:
6782 Suppose that idom(X) = Y before removal of E and idom(X) != Y after the
6783 removal. Let Z the arbitrary block such that idom(Z) = Y and
6784 Z dominates X after the removal. Before removal, there exists a path P
6785 from Y to X that avoids Z. Let F be the last edge on P that is
6786 removed, and let W = F->dest. Before removal, idom(W) = Y (since Y
6787 dominates W, and because of P, Z does not dominate W), and W belongs to
6788 the dominance frontier of E. Therefore, Y belongs to DF_IDOM. */
6789 EXECUTE_IF_SET_IN_BITMAP (df_idom, 0, i, bi)
6791 bb = BASIC_BLOCK (i);
6792 for (dbb = first_dom_son (CDI_DOMINATORS, bb);
6794 dbb = next_dom_son (CDI_DOMINATORS, dbb))
6795 VEC_safe_push (basic_block, heap, bbs_to_fix_dom, dbb);
6798 iterate_fix_dominators (CDI_DOMINATORS, bbs_to_fix_dom, true);
6801 BITMAP_FREE (df_idom);
6802 VEC_free (basic_block, heap, bbs_to_remove);
6803 VEC_free (basic_block, heap, bbs_to_fix_dom);
6806 /* Purge dead EH edges from basic block BB. */
6809 gimple_purge_dead_eh_edges (basic_block bb)
6811 bool changed = false;
6814 gimple stmt = last_stmt (bb);
6816 if (stmt && stmt_can_throw_internal (stmt))
6819 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6821 if (e->flags & EDGE_EH)
6823 remove_edge_and_dominated_blocks (e);
6834 gimple_purge_all_dead_eh_edges (const_bitmap blocks)
6836 bool changed = false;
6840 EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
6842 basic_block bb = BASIC_BLOCK (i);
6844 /* Earlier gimple_purge_dead_eh_edges could have removed
6845 this basic block already. */
6846 gcc_assert (bb || changed);
6848 changed |= gimple_purge_dead_eh_edges (bb);
6854 /* This function is called whenever a new edge is created or
6858 gimple_execute_on_growing_pred (edge e)
6860 basic_block bb = e->dest;
6863 reserve_phi_args_for_new_edge (bb);
6866 /* This function is called immediately before edge E is removed from
6867 the edge vector E->dest->preds. */
6870 gimple_execute_on_shrinking_pred (edge e)
6872 if (phi_nodes (e->dest))
6873 remove_phi_args (e);
6876 /*---------------------------------------------------------------------------
6877 Helper functions for Loop versioning
6878 ---------------------------------------------------------------------------*/
6880 /* Adjust phi nodes for 'first' basic block. 'second' basic block is a copy
6881 of 'first'. Both of them are dominated by 'new_head' basic block. When
6882 'new_head' was created by 'second's incoming edge it received phi arguments
6883 on the edge by split_edge(). Later, additional edge 'e' was created to
6884 connect 'new_head' and 'first'. Now this routine adds phi args on this
6885 additional edge 'e' that new_head to second edge received as part of edge
6889 gimple_lv_adjust_loop_header_phi (basic_block first, basic_block second,
6890 basic_block new_head, edge e)
6893 gimple_stmt_iterator psi1, psi2;
6895 edge e2 = find_edge (new_head, second);
6897 /* Because NEW_HEAD has been created by splitting SECOND's incoming
6898 edge, we should always have an edge from NEW_HEAD to SECOND. */
6899 gcc_assert (e2 != NULL);
6901 /* Browse all 'second' basic block phi nodes and add phi args to
6902 edge 'e' for 'first' head. PHI args are always in correct order. */
6904 for (psi2 = gsi_start_phis (second),
6905 psi1 = gsi_start_phis (first);
6906 !gsi_end_p (psi2) && !gsi_end_p (psi1);
6907 gsi_next (&psi2), gsi_next (&psi1))
6909 phi1 = gsi_stmt (psi1);
6910 phi2 = gsi_stmt (psi2);
6911 def = PHI_ARG_DEF (phi2, e2->dest_idx);
6912 add_phi_arg (phi1, def, e);
6917 /* Adds a if else statement to COND_BB with condition COND_EXPR.
6918 SECOND_HEAD is the destination of the THEN and FIRST_HEAD is
6919 the destination of the ELSE part. */
6922 gimple_lv_add_condition_to_bb (basic_block first_head ATTRIBUTE_UNUSED,
6923 basic_block second_head ATTRIBUTE_UNUSED,
6924 basic_block cond_bb, void *cond_e)
6926 gimple_stmt_iterator gsi;
6927 gimple new_cond_expr;
6928 tree cond_expr = (tree) cond_e;
6931 /* Build new conditional expr */
6932 new_cond_expr = gimple_build_cond_from_tree (cond_expr,
6933 NULL_TREE, NULL_TREE);
6935 /* Add new cond in cond_bb. */
6936 gsi = gsi_last_bb (cond_bb);
6937 gsi_insert_after (&gsi, new_cond_expr, GSI_NEW_STMT);
6939 /* Adjust edges appropriately to connect new head with first head
6940 as well as second head. */
6941 e0 = single_succ_edge (cond_bb);
6942 e0->flags &= ~EDGE_FALLTHRU;
6943 e0->flags |= EDGE_FALSE_VALUE;
6946 struct cfg_hooks gimple_cfg_hooks = {
6948 gimple_verify_flow_info,
6949 gimple_dump_bb, /* dump_bb */
6950 create_bb, /* create_basic_block */
6951 gimple_redirect_edge_and_branch, /* redirect_edge_and_branch */
6952 gimple_redirect_edge_and_branch_force, /* redirect_edge_and_branch_force */
6953 gimple_can_remove_branch_p, /* can_remove_branch_p */
6954 remove_bb, /* delete_basic_block */
6955 gimple_split_block, /* split_block */
6956 gimple_move_block_after, /* move_block_after */
6957 gimple_can_merge_blocks_p, /* can_merge_blocks_p */
6958 gimple_merge_blocks, /* merge_blocks */
6959 gimple_predict_edge, /* predict_edge */
6960 gimple_predicted_by_p, /* predicted_by_p */
6961 gimple_can_duplicate_bb_p, /* can_duplicate_block_p */
6962 gimple_duplicate_bb, /* duplicate_block */
6963 gimple_split_edge, /* split_edge */
6964 gimple_make_forwarder_block, /* make_forward_block */
6965 NULL, /* tidy_fallthru_edge */
6966 gimple_block_ends_with_call_p,/* block_ends_with_call_p */
6967 gimple_block_ends_with_condjump_p, /* block_ends_with_condjump_p */
6968 gimple_flow_call_edges_add, /* flow_call_edges_add */
6969 gimple_execute_on_growing_pred, /* execute_on_growing_pred */
6970 gimple_execute_on_shrinking_pred, /* execute_on_shrinking_pred */
6971 gimple_duplicate_loop_to_header_edge, /* duplicate loop for trees */
6972 gimple_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
6973 gimple_lv_adjust_loop_header_phi, /* lv_adjust_loop_header_phi*/
6974 extract_true_false_edges_from_block, /* extract_cond_bb_edges */
6975 flush_pending_stmts /* flush_pending_stmts */
6979 /* Split all critical edges. */
6982 split_critical_edges (void)
6988 /* split_edge can redirect edges out of SWITCH_EXPRs, which can get
6989 expensive. So we want to enable recording of edge to CASE_LABEL_EXPR
6990 mappings around the calls to split_edge. */
6991 start_recording_case_labels ();
6994 FOR_EACH_EDGE (e, ei, bb->succs)
6996 if (EDGE_CRITICAL_P (e) && !(e->flags & EDGE_ABNORMAL))
6998 /* PRE inserts statements to edges and expects that
6999 since split_critical_edges was done beforehand, committing edge
7000 insertions will not split more edges. In addition to critical
7001 edges we must split edges that have multiple successors and
7002 end by control flow statements, such as RESX.
7003 Go ahead and split them too. This matches the logic in
7004 gimple_find_edge_insert_loc. */
7005 else if ((!single_pred_p (e->dest)
7006 || phi_nodes (e->dest)
7007 || e->dest == EXIT_BLOCK_PTR)
7008 && e->src != ENTRY_BLOCK_PTR
7009 && !(e->flags & EDGE_ABNORMAL))
7011 gimple_stmt_iterator gsi;
7013 gsi = gsi_last_bb (e->src);
7014 if (!gsi_end_p (gsi)
7015 && stmt_ends_bb_p (gsi_stmt (gsi))
7016 && gimple_code (gsi_stmt (gsi)) != GIMPLE_RETURN)
7021 end_recording_case_labels ();
7025 struct gimple_opt_pass pass_split_crit_edges =
7029 "crited", /* name */
7031 split_critical_edges, /* execute */
7034 0, /* static_pass_number */
7035 TV_TREE_SPLIT_EDGES, /* tv_id */
7036 PROP_cfg, /* properties required */
7037 PROP_no_crit_edges, /* properties_provided */
7038 0, /* properties_destroyed */
7039 0, /* todo_flags_start */
7040 TODO_dump_func /* todo_flags_finish */
7045 /* Build a ternary operation and gimplify it. Emit code before GSI.
7046 Return the gimple_val holding the result. */
7049 gimplify_build3 (gimple_stmt_iterator *gsi, enum tree_code code,
7050 tree type, tree a, tree b, tree c)
7054 ret = fold_build3 (code, type, a, b, c);
7057 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7061 /* Build a binary operation and gimplify it. Emit code before GSI.
7062 Return the gimple_val holding the result. */
7065 gimplify_build2 (gimple_stmt_iterator *gsi, enum tree_code code,
7066 tree type, tree a, tree b)
7070 ret = fold_build2 (code, type, a, b);
7073 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7077 /* Build a unary operation and gimplify it. Emit code before GSI.
7078 Return the gimple_val holding the result. */
7081 gimplify_build1 (gimple_stmt_iterator *gsi, enum tree_code code, tree type,
7086 ret = fold_build1 (code, type, a);
7089 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7095 /* Emit return warnings. */
7098 execute_warn_function_return (void)
7100 source_location location;
7105 /* If we have a path to EXIT, then we do return. */
7106 if (TREE_THIS_VOLATILE (cfun->decl)
7107 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0)
7109 location = UNKNOWN_LOCATION;
7110 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7112 last = last_stmt (e->src);
7113 if (gimple_code (last) == GIMPLE_RETURN
7114 && (location = gimple_location (last)) != UNKNOWN_LOCATION)
7117 if (location == UNKNOWN_LOCATION)
7118 location = cfun->function_end_locus;
7119 warning (0, "%H%<noreturn%> function does return", &location);
7122 /* If we see "return;" in some basic block, then we do reach the end
7123 without returning a value. */
7124 else if (warn_return_type
7125 && !TREE_NO_WARNING (cfun->decl)
7126 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0
7127 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (cfun->decl))))
7129 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7131 gimple last = last_stmt (e->src);
7132 if (gimple_code (last) == GIMPLE_RETURN
7133 && gimple_return_retval (last) == NULL
7134 && !gimple_no_warning_p (last))
7136 location = gimple_location (last);
7137 if (location == UNKNOWN_LOCATION)
7138 location = cfun->function_end_locus;
7139 warning_at (location, OPT_Wreturn_type, "control reaches end of non-void function");
7140 TREE_NO_WARNING (cfun->decl) = 1;
7149 /* Given a basic block B which ends with a conditional and has
7150 precisely two successors, determine which of the edges is taken if
7151 the conditional is true and which is taken if the conditional is
7152 false. Set TRUE_EDGE and FALSE_EDGE appropriately. */
7155 extract_true_false_edges_from_block (basic_block b,
7159 edge e = EDGE_SUCC (b, 0);
7161 if (e->flags & EDGE_TRUE_VALUE)
7164 *false_edge = EDGE_SUCC (b, 1);
7169 *true_edge = EDGE_SUCC (b, 1);
7173 struct gimple_opt_pass pass_warn_function_return =
7179 execute_warn_function_return, /* execute */
7182 0, /* static_pass_number */
7183 TV_NONE, /* tv_id */
7184 PROP_cfg, /* properties_required */
7185 0, /* properties_provided */
7186 0, /* properties_destroyed */
7187 0, /* todo_flags_start */
7188 0 /* todo_flags_finish */
7192 /* Emit noreturn warnings. */
7195 execute_warn_function_noreturn (void)
7197 if (warn_missing_noreturn
7198 && !TREE_THIS_VOLATILE (cfun->decl)
7199 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0
7200 && !lang_hooks.missing_noreturn_ok_p (cfun->decl))
7201 warning (OPT_Wmissing_noreturn, "%Jfunction might be possible candidate "
7202 "for attribute %<noreturn%>",
7207 struct gimple_opt_pass pass_warn_function_noreturn =
7213 execute_warn_function_noreturn, /* execute */
7216 0, /* static_pass_number */
7217 TV_NONE, /* tv_id */
7218 PROP_cfg, /* properties_required */
7219 0, /* properties_provided */
7220 0, /* properties_destroyed */
7221 0, /* todo_flags_start */
7222 0 /* todo_flags_finish */