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);
2088 #ifdef ENABLE_TYPES_CHECKING
2089 verify_types_in_gimple_seq (gimple_body (current_function_decl));
2096 struct gimple_opt_pass pass_remove_useless_stmts =
2100 "useless", /* name */
2102 remove_useless_stmts, /* execute */
2105 0, /* static_pass_number */
2106 TV_NONE, /* tv_id */
2107 PROP_gimple_any, /* properties_required */
2108 0, /* properties_provided */
2109 0, /* properties_destroyed */
2110 0, /* todo_flags_start */
2111 TODO_dump_func /* todo_flags_finish */
2115 /* Remove PHI nodes associated with basic block BB and all edges out of BB. */
2118 remove_phi_nodes_and_edges_for_unreachable_block (basic_block bb)
2120 /* Since this block is no longer reachable, we can just delete all
2121 of its PHI nodes. */
2122 remove_phi_nodes (bb);
2124 /* Remove edges to BB's successors. */
2125 while (EDGE_COUNT (bb->succs) > 0)
2126 remove_edge (EDGE_SUCC (bb, 0));
2130 /* Remove statements of basic block BB. */
2133 remove_bb (basic_block bb)
2135 gimple_stmt_iterator i;
2136 source_location loc = UNKNOWN_LOCATION;
2140 fprintf (dump_file, "Removing basic block %d\n", bb->index);
2141 if (dump_flags & TDF_DETAILS)
2143 dump_bb (bb, dump_file, 0);
2144 fprintf (dump_file, "\n");
2150 struct loop *loop = bb->loop_father;
2152 /* If a loop gets removed, clean up the information associated
2154 if (loop->latch == bb
2155 || loop->header == bb)
2156 free_numbers_of_iterations_estimates_loop (loop);
2159 /* Remove all the instructions in the block. */
2160 if (bb_seq (bb) != NULL)
2162 for (i = gsi_start_bb (bb); !gsi_end_p (i);)
2164 gimple stmt = gsi_stmt (i);
2165 if (gimple_code (stmt) == GIMPLE_LABEL
2166 && (FORCED_LABEL (gimple_label_label (stmt))
2167 || DECL_NONLOCAL (gimple_label_label (stmt))))
2170 gimple_stmt_iterator new_gsi;
2172 /* A non-reachable non-local label may still be referenced.
2173 But it no longer needs to carry the extra semantics of
2175 if (DECL_NONLOCAL (gimple_label_label (stmt)))
2177 DECL_NONLOCAL (gimple_label_label (stmt)) = 0;
2178 FORCED_LABEL (gimple_label_label (stmt)) = 1;
2181 new_bb = bb->prev_bb;
2182 new_gsi = gsi_start_bb (new_bb);
2183 gsi_remove (&i, false);
2184 gsi_insert_before (&new_gsi, stmt, GSI_NEW_STMT);
2188 /* Release SSA definitions if we are in SSA. Note that we
2189 may be called when not in SSA. For example,
2190 final_cleanup calls this function via
2191 cleanup_tree_cfg. */
2192 if (gimple_in_ssa_p (cfun))
2193 release_defs (stmt);
2195 gsi_remove (&i, true);
2198 /* Don't warn for removed gotos. Gotos are often removed due to
2199 jump threading, thus resulting in bogus warnings. Not great,
2200 since this way we lose warnings for gotos in the original
2201 program that are indeed unreachable. */
2202 if (gimple_code (stmt) != GIMPLE_GOTO
2203 && gimple_has_location (stmt)
2205 loc = gimple_location (stmt);
2209 /* If requested, give a warning that the first statement in the
2210 block is unreachable. We walk statements backwards in the
2211 loop above, so the last statement we process is the first statement
2213 if (loc > BUILTINS_LOCATION && LOCATION_LINE (loc) > 0)
2214 warning (OPT_Wunreachable_code, "%Hwill never be executed", &loc);
2216 remove_phi_nodes_and_edges_for_unreachable_block (bb);
2217 bb->il.gimple = NULL;
2221 /* Given a basic block BB ending with COND_EXPR or SWITCH_EXPR, and a
2222 predicate VAL, return the edge that will be taken out of the block.
2223 If VAL does not match a unique edge, NULL is returned. */
2226 find_taken_edge (basic_block bb, tree val)
2230 stmt = last_stmt (bb);
2233 gcc_assert (is_ctrl_stmt (stmt));
2238 if (!is_gimple_min_invariant (val))
2241 if (gimple_code (stmt) == GIMPLE_COND)
2242 return find_taken_edge_cond_expr (bb, val);
2244 if (gimple_code (stmt) == GIMPLE_SWITCH)
2245 return find_taken_edge_switch_expr (bb, val);
2247 if (computed_goto_p (stmt))
2249 /* Only optimize if the argument is a label, if the argument is
2250 not a label then we can not construct a proper CFG.
2252 It may be the case that we only need to allow the LABEL_REF to
2253 appear inside an ADDR_EXPR, but we also allow the LABEL_REF to
2254 appear inside a LABEL_EXPR just to be safe. */
2255 if ((TREE_CODE (val) == ADDR_EXPR || TREE_CODE (val) == LABEL_EXPR)
2256 && TREE_CODE (TREE_OPERAND (val, 0)) == LABEL_DECL)
2257 return find_taken_edge_computed_goto (bb, TREE_OPERAND (val, 0));
2264 /* Given a constant value VAL and the entry block BB to a GOTO_EXPR
2265 statement, determine which of the outgoing edges will be taken out of the
2266 block. Return NULL if either edge may be taken. */
2269 find_taken_edge_computed_goto (basic_block bb, tree val)
2274 dest = label_to_block (val);
2277 e = find_edge (bb, dest);
2278 gcc_assert (e != NULL);
2284 /* Given a constant value VAL and the entry block BB to a COND_EXPR
2285 statement, determine which of the two edges will be taken out of the
2286 block. Return NULL if either edge may be taken. */
2289 find_taken_edge_cond_expr (basic_block bb, tree val)
2291 edge true_edge, false_edge;
2293 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
2295 gcc_assert (TREE_CODE (val) == INTEGER_CST);
2296 return (integer_zerop (val) ? false_edge : true_edge);
2299 /* Given an INTEGER_CST VAL and the entry block BB to a SWITCH_EXPR
2300 statement, determine which edge will be taken out of the block. Return
2301 NULL if any edge may be taken. */
2304 find_taken_edge_switch_expr (basic_block bb, tree val)
2306 basic_block dest_bb;
2311 switch_stmt = last_stmt (bb);
2312 taken_case = find_case_label_for_value (switch_stmt, val);
2313 dest_bb = label_to_block (CASE_LABEL (taken_case));
2315 e = find_edge (bb, dest_bb);
2321 /* Return the CASE_LABEL_EXPR that SWITCH_STMT will take for VAL.
2322 We can make optimal use here of the fact that the case labels are
2323 sorted: We can do a binary search for a case matching VAL. */
2326 find_case_label_for_value (gimple switch_stmt, tree val)
2328 size_t low, high, n = gimple_switch_num_labels (switch_stmt);
2329 tree default_case = gimple_switch_default_label (switch_stmt);
2331 for (low = 0, high = n; high - low > 1; )
2333 size_t i = (high + low) / 2;
2334 tree t = gimple_switch_label (switch_stmt, i);
2337 /* Cache the result of comparing CASE_LOW and val. */
2338 cmp = tree_int_cst_compare (CASE_LOW (t), val);
2345 if (CASE_HIGH (t) == NULL)
2347 /* A singe-valued case label. */
2353 /* A case range. We can only handle integer ranges. */
2354 if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
2359 return default_case;
2363 /* Dump a basic block on stderr. */
2366 gimple_debug_bb (basic_block bb)
2368 gimple_dump_bb (bb, stderr, 0, TDF_VOPS|TDF_MEMSYMS);
2372 /* Dump basic block with index N on stderr. */
2375 gimple_debug_bb_n (int n)
2377 gimple_debug_bb (BASIC_BLOCK (n));
2378 return BASIC_BLOCK (n);
2382 /* Dump the CFG on stderr.
2384 FLAGS are the same used by the tree dumping functions
2385 (see TDF_* in tree-pass.h). */
2388 gimple_debug_cfg (int flags)
2390 gimple_dump_cfg (stderr, flags);
2394 /* Dump the program showing basic block boundaries on the given FILE.
2396 FLAGS are the same used by the tree dumping functions (see TDF_* in
2400 gimple_dump_cfg (FILE *file, int flags)
2402 if (flags & TDF_DETAILS)
2404 const char *funcname
2405 = lang_hooks.decl_printable_name (current_function_decl, 2);
2408 fprintf (file, ";; Function %s\n\n", funcname);
2409 fprintf (file, ";; \n%d basic blocks, %d edges, last basic block %d.\n\n",
2410 n_basic_blocks, n_edges, last_basic_block);
2412 brief_dump_cfg (file);
2413 fprintf (file, "\n");
2416 if (flags & TDF_STATS)
2417 dump_cfg_stats (file);
2419 dump_function_to_file (current_function_decl, file, flags | TDF_BLOCKS);
2423 /* Dump CFG statistics on FILE. */
2426 dump_cfg_stats (FILE *file)
2428 static long max_num_merged_labels = 0;
2429 unsigned long size, total = 0;
2432 const char * const fmt_str = "%-30s%-13s%12s\n";
2433 const char * const fmt_str_1 = "%-30s%13d%11lu%c\n";
2434 const char * const fmt_str_2 = "%-30s%13ld%11lu%c\n";
2435 const char * const fmt_str_3 = "%-43s%11lu%c\n";
2436 const char *funcname
2437 = lang_hooks.decl_printable_name (current_function_decl, 2);
2440 fprintf (file, "\nCFG Statistics for %s\n\n", funcname);
2442 fprintf (file, "---------------------------------------------------------\n");
2443 fprintf (file, fmt_str, "", " Number of ", "Memory");
2444 fprintf (file, fmt_str, "", " instances ", "used ");
2445 fprintf (file, "---------------------------------------------------------\n");
2447 size = n_basic_blocks * sizeof (struct basic_block_def);
2449 fprintf (file, fmt_str_1, "Basic blocks", n_basic_blocks,
2450 SCALE (size), LABEL (size));
2454 num_edges += EDGE_COUNT (bb->succs);
2455 size = num_edges * sizeof (struct edge_def);
2457 fprintf (file, fmt_str_2, "Edges", num_edges, SCALE (size), LABEL (size));
2459 fprintf (file, "---------------------------------------------------------\n");
2460 fprintf (file, fmt_str_3, "Total memory used by CFG data", SCALE (total),
2462 fprintf (file, "---------------------------------------------------------\n");
2463 fprintf (file, "\n");
2465 if (cfg_stats.num_merged_labels > max_num_merged_labels)
2466 max_num_merged_labels = cfg_stats.num_merged_labels;
2468 fprintf (file, "Coalesced label blocks: %ld (Max so far: %ld)\n",
2469 cfg_stats.num_merged_labels, max_num_merged_labels);
2471 fprintf (file, "\n");
2475 /* Dump CFG statistics on stderr. Keep extern so that it's always
2476 linked in the final executable. */
2479 debug_cfg_stats (void)
2481 dump_cfg_stats (stderr);
2485 /* Dump the flowgraph to a .vcg FILE. */
2488 gimple_cfg2vcg (FILE *file)
2493 const char *funcname
2494 = lang_hooks.decl_printable_name (current_function_decl, 2);
2496 /* Write the file header. */
2497 fprintf (file, "graph: { title: \"%s\"\n", funcname);
2498 fprintf (file, "node: { title: \"ENTRY\" label: \"ENTRY\" }\n");
2499 fprintf (file, "node: { title: \"EXIT\" label: \"EXIT\" }\n");
2501 /* Write blocks and edges. */
2502 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
2504 fprintf (file, "edge: { sourcename: \"ENTRY\" targetname: \"%d\"",
2507 if (e->flags & EDGE_FAKE)
2508 fprintf (file, " linestyle: dotted priority: 10");
2510 fprintf (file, " linestyle: solid priority: 100");
2512 fprintf (file, " }\n");
2518 enum gimple_code head_code, end_code;
2519 const char *head_name, *end_name;
2522 gimple first = first_stmt (bb);
2523 gimple last = last_stmt (bb);
2527 head_code = gimple_code (first);
2528 head_name = gimple_code_name[head_code];
2529 head_line = get_lineno (first);
2532 head_name = "no-statement";
2536 end_code = gimple_code (last);
2537 end_name = gimple_code_name[end_code];
2538 end_line = get_lineno (last);
2541 end_name = "no-statement";
2543 fprintf (file, "node: { title: \"%d\" label: \"#%d\\n%s (%d)\\n%s (%d)\"}\n",
2544 bb->index, bb->index, head_name, head_line, end_name,
2547 FOR_EACH_EDGE (e, ei, bb->succs)
2549 if (e->dest == EXIT_BLOCK_PTR)
2550 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"EXIT\"", bb->index);
2552 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"%d\"", bb->index, e->dest->index);
2554 if (e->flags & EDGE_FAKE)
2555 fprintf (file, " priority: 10 linestyle: dotted");
2557 fprintf (file, " priority: 100 linestyle: solid");
2559 fprintf (file, " }\n");
2562 if (bb->next_bb != EXIT_BLOCK_PTR)
2566 fputs ("}\n\n", file);
2571 /*---------------------------------------------------------------------------
2572 Miscellaneous helpers
2573 ---------------------------------------------------------------------------*/
2575 /* Return true if T represents a stmt that always transfers control. */
2578 is_ctrl_stmt (gimple t)
2580 return gimple_code (t) == GIMPLE_COND
2581 || gimple_code (t) == GIMPLE_SWITCH
2582 || gimple_code (t) == GIMPLE_GOTO
2583 || gimple_code (t) == GIMPLE_RETURN
2584 || gimple_code (t) == GIMPLE_RESX;
2588 /* Return true if T is a statement that may alter the flow of control
2589 (e.g., a call to a non-returning function). */
2592 is_ctrl_altering_stmt (gimple t)
2596 if (is_gimple_call (t))
2598 int flags = gimple_call_flags (t);
2600 /* A non-pure/const call alters flow control if the current
2601 function has nonlocal labels. */
2602 if (!(flags & (ECF_CONST | ECF_PURE))
2603 && cfun->has_nonlocal_label)
2606 /* A call also alters control flow if it does not return. */
2607 if (gimple_call_flags (t) & ECF_NORETURN)
2611 /* OpenMP directives alter control flow. */
2612 if (is_gimple_omp (t))
2615 /* If a statement can throw, it alters control flow. */
2616 return stmt_can_throw_internal (t);
2620 /* Return true if T is a simple local goto. */
2623 simple_goto_p (gimple t)
2625 return (gimple_code (t) == GIMPLE_GOTO
2626 && TREE_CODE (gimple_goto_dest (t)) == LABEL_DECL);
2630 /* Return true if T can make an abnormal transfer of control flow.
2631 Transfers of control flow associated with EH are excluded. */
2634 stmt_can_make_abnormal_goto (gimple t)
2636 if (computed_goto_p (t))
2638 if (is_gimple_call (t))
2639 return gimple_has_side_effects (t) && cfun->has_nonlocal_label;
2644 /* Return true if STMT should start a new basic block. PREV_STMT is
2645 the statement preceding STMT. It is used when STMT is a label or a
2646 case label. Labels should only start a new basic block if their
2647 previous statement wasn't a label. Otherwise, sequence of labels
2648 would generate unnecessary basic blocks that only contain a single
2652 stmt_starts_bb_p (gimple stmt, gimple prev_stmt)
2657 /* Labels start a new basic block only if the preceding statement
2658 wasn't a label of the same type. This prevents the creation of
2659 consecutive blocks that have nothing but a single label. */
2660 if (gimple_code (stmt) == GIMPLE_LABEL)
2662 /* Nonlocal and computed GOTO targets always start a new block. */
2663 if (DECL_NONLOCAL (gimple_label_label (stmt))
2664 || FORCED_LABEL (gimple_label_label (stmt)))
2667 if (prev_stmt && gimple_code (prev_stmt) == GIMPLE_LABEL)
2669 if (DECL_NONLOCAL (gimple_label_label (prev_stmt)))
2672 cfg_stats.num_merged_labels++;
2683 /* Return true if T should end a basic block. */
2686 stmt_ends_bb_p (gimple t)
2688 return is_ctrl_stmt (t) || is_ctrl_altering_stmt (t);
2691 /* Remove block annotations and other data structures. */
2694 delete_tree_cfg_annotations (void)
2696 label_to_block_map = NULL;
2700 /* Return the first statement in basic block BB. */
2703 first_stmt (basic_block bb)
2705 gimple_stmt_iterator i = gsi_start_bb (bb);
2706 return !gsi_end_p (i) ? gsi_stmt (i) : NULL;
2709 /* Return the last statement in basic block BB. */
2712 last_stmt (basic_block bb)
2714 gimple_stmt_iterator b = gsi_last_bb (bb);
2715 return !gsi_end_p (b) ? gsi_stmt (b) : NULL;
2718 /* Return the last statement of an otherwise empty block. Return NULL
2719 if the block is totally empty, or if it contains more than one
2723 last_and_only_stmt (basic_block bb)
2725 gimple_stmt_iterator i = gsi_last_bb (bb);
2731 last = gsi_stmt (i);
2736 /* Empty statements should no longer appear in the instruction stream.
2737 Everything that might have appeared before should be deleted by
2738 remove_useless_stmts, and the optimizers should just gsi_remove
2739 instead of smashing with build_empty_stmt.
2741 Thus the only thing that should appear here in a block containing
2742 one executable statement is a label. */
2743 prev = gsi_stmt (i);
2744 if (gimple_code (prev) == GIMPLE_LABEL)
2750 /* Reinstall those PHI arguments queued in OLD_EDGE to NEW_EDGE. */
2753 reinstall_phi_args (edge new_edge, edge old_edge)
2755 edge_var_map_vector v;
2758 gimple_stmt_iterator phis;
2760 v = redirect_edge_var_map_vector (old_edge);
2764 for (i = 0, phis = gsi_start_phis (new_edge->dest);
2765 VEC_iterate (edge_var_map, v, i, vm) && !gsi_end_p (phis);
2766 i++, gsi_next (&phis))
2768 gimple phi = gsi_stmt (phis);
2769 tree result = redirect_edge_var_map_result (vm);
2770 tree arg = redirect_edge_var_map_def (vm);
2772 gcc_assert (result == gimple_phi_result (phi));
2774 add_phi_arg (phi, arg, new_edge);
2777 redirect_edge_var_map_clear (old_edge);
2780 /* Returns the basic block after which the new basic block created
2781 by splitting edge EDGE_IN should be placed. Tries to keep the new block
2782 near its "logical" location. This is of most help to humans looking
2783 at debugging dumps. */
2786 split_edge_bb_loc (edge edge_in)
2788 basic_block dest = edge_in->dest;
2790 if (dest->prev_bb && find_edge (dest->prev_bb, dest))
2791 return edge_in->src;
2793 return dest->prev_bb;
2796 /* Split a (typically critical) edge EDGE_IN. Return the new block.
2797 Abort on abnormal edges. */
2800 gimple_split_edge (edge edge_in)
2802 basic_block new_bb, after_bb, dest;
2805 /* Abnormal edges cannot be split. */
2806 gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
2808 dest = edge_in->dest;
2810 after_bb = split_edge_bb_loc (edge_in);
2812 new_bb = create_empty_bb (after_bb);
2813 new_bb->frequency = EDGE_FREQUENCY (edge_in);
2814 new_bb->count = edge_in->count;
2815 new_edge = make_edge (new_bb, dest, EDGE_FALLTHRU);
2816 new_edge->probability = REG_BR_PROB_BASE;
2817 new_edge->count = edge_in->count;
2819 e = redirect_edge_and_branch (edge_in, new_bb);
2820 gcc_assert (e == edge_in);
2821 reinstall_phi_args (new_edge, e);
2826 /* Callback for walk_tree, check that all elements with address taken are
2827 properly noticed as such. The DATA is an int* that is 1 if TP was seen
2828 inside a PHI node. */
2831 verify_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
2838 /* Check operand N for being valid GIMPLE and give error MSG if not. */
2839 #define CHECK_OP(N, MSG) \
2840 do { if (!is_gimple_val (TREE_OPERAND (t, N))) \
2841 { error (MSG); return TREE_OPERAND (t, N); }} while (0)
2843 switch (TREE_CODE (t))
2846 if (SSA_NAME_IN_FREE_LIST (t))
2848 error ("SSA name in freelist but still referenced");
2854 x = TREE_OPERAND (t, 0);
2855 if (!is_gimple_reg (x) && !is_gimple_min_invariant (x))
2857 error ("Indirect reference's operand is not a register or a constant.");
2863 x = fold (ASSERT_EXPR_COND (t));
2864 if (x == boolean_false_node)
2866 error ("ASSERT_EXPR with an always-false condition");
2872 error ("MODIFY_EXPR not expected while having tuples.");
2878 bool old_side_effects;
2880 bool new_side_effects;
2882 gcc_assert (is_gimple_address (t));
2884 old_constant = TREE_CONSTANT (t);
2885 old_side_effects = TREE_SIDE_EFFECTS (t);
2887 recompute_tree_invariant_for_addr_expr (t);
2888 new_side_effects = TREE_SIDE_EFFECTS (t);
2889 new_constant = TREE_CONSTANT (t);
2891 if (old_constant != new_constant)
2893 error ("constant not recomputed when ADDR_EXPR changed");
2896 if (old_side_effects != new_side_effects)
2898 error ("side effects not recomputed when ADDR_EXPR changed");
2902 /* Skip any references (they will be checked when we recurse down the
2903 tree) and ensure that any variable used as a prefix is marked
2905 for (x = TREE_OPERAND (t, 0);
2906 handled_component_p (x);
2907 x = TREE_OPERAND (x, 0))
2910 if (!(TREE_CODE (x) == VAR_DECL
2911 || TREE_CODE (x) == PARM_DECL
2912 || TREE_CODE (x) == RESULT_DECL))
2914 if (!TREE_ADDRESSABLE (x))
2916 error ("address taken, but ADDRESSABLE bit not set");
2919 if (DECL_GIMPLE_REG_P (x))
2921 error ("DECL_GIMPLE_REG_P set on a variable with address taken");
2929 x = COND_EXPR_COND (t);
2930 if (!INTEGRAL_TYPE_P (TREE_TYPE (x)))
2932 error ("non-integral used in condition");
2935 if (!is_gimple_condexpr (x))
2937 error ("invalid conditional operand");
2942 case NON_LVALUE_EXPR:
2946 case FIX_TRUNC_EXPR:
2951 case TRUTH_NOT_EXPR:
2952 CHECK_OP (0, "invalid operand to unary operator");
2959 case ARRAY_RANGE_REF:
2961 case VIEW_CONVERT_EXPR:
2962 /* We have a nest of references. Verify that each of the operands
2963 that determine where to reference is either a constant or a variable,
2964 verify that the base is valid, and then show we've already checked
2966 while (handled_component_p (t))
2968 if (TREE_CODE (t) == COMPONENT_REF && TREE_OPERAND (t, 2))
2969 CHECK_OP (2, "invalid COMPONENT_REF offset operator");
2970 else if (TREE_CODE (t) == ARRAY_REF
2971 || TREE_CODE (t) == ARRAY_RANGE_REF)
2973 CHECK_OP (1, "invalid array index");
2974 if (TREE_OPERAND (t, 2))
2975 CHECK_OP (2, "invalid array lower bound");
2976 if (TREE_OPERAND (t, 3))
2977 CHECK_OP (3, "invalid array stride");
2979 else if (TREE_CODE (t) == BIT_FIELD_REF)
2981 if (!host_integerp (TREE_OPERAND (t, 1), 1)
2982 || !host_integerp (TREE_OPERAND (t, 2), 1))
2984 error ("invalid position or size operand to BIT_FIELD_REF");
2987 else if (INTEGRAL_TYPE_P (TREE_TYPE (t))
2988 && (TYPE_PRECISION (TREE_TYPE (t))
2989 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
2991 error ("integral result type precision does not match "
2992 "field size of BIT_FIELD_REF");
2995 if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
2996 && (GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (t)))
2997 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
2999 error ("mode precision of non-integral result does not "
3000 "match field size of BIT_FIELD_REF");
3005 t = TREE_OPERAND (t, 0);
3008 if (!is_gimple_min_invariant (t) && !is_gimple_lvalue (t))
3010 error ("invalid reference prefix");
3017 /* PLUS_EXPR and MINUS_EXPR don't work on pointers, they should be done using
3018 POINTER_PLUS_EXPR. */
3019 if (POINTER_TYPE_P (TREE_TYPE (t)))
3021 error ("invalid operand to plus/minus, type is a pointer");
3024 CHECK_OP (0, "invalid operand to binary operator");
3025 CHECK_OP (1, "invalid operand to binary operator");
3028 case POINTER_PLUS_EXPR:
3029 /* Check to make sure the first operand is a pointer or reference type. */
3030 if (!POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 0))))
3032 error ("invalid operand to pointer plus, first operand is not a pointer");
3035 /* Check to make sure the second operand is an integer with type of
3037 if (!useless_type_conversion_p (sizetype,
3038 TREE_TYPE (TREE_OPERAND (t, 1))))
3040 error ("invalid operand to pointer plus, second operand is not an "
3041 "integer with type of sizetype.");
3051 case UNORDERED_EXPR:
3060 case TRUNC_DIV_EXPR:
3062 case FLOOR_DIV_EXPR:
3063 case ROUND_DIV_EXPR:
3064 case TRUNC_MOD_EXPR:
3066 case FLOOR_MOD_EXPR:
3067 case ROUND_MOD_EXPR:
3069 case EXACT_DIV_EXPR:
3079 CHECK_OP (0, "invalid operand to binary operator");
3080 CHECK_OP (1, "invalid operand to binary operator");
3084 if (TREE_CONSTANT (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
3097 /* Verify if EXPR is either a GIMPLE ID or a GIMPLE indirect reference.
3098 Returns true if there is an error, otherwise false. */
3101 verify_types_in_gimple_min_lval (tree expr)
3105 if (is_gimple_id (expr))
3108 if (!INDIRECT_REF_P (expr)
3109 && TREE_CODE (expr) != TARGET_MEM_REF)
3111 error ("invalid expression for min lvalue");
3115 /* TARGET_MEM_REFs are strange beasts. */
3116 if (TREE_CODE (expr) == TARGET_MEM_REF)
3119 op = TREE_OPERAND (expr, 0);
3120 if (!is_gimple_val (op))
3122 error ("invalid operand in indirect reference");
3123 debug_generic_stmt (op);
3126 if (!useless_type_conversion_p (TREE_TYPE (expr),
3127 TREE_TYPE (TREE_TYPE (op))))
3129 error ("type mismatch in indirect reference");
3130 debug_generic_stmt (TREE_TYPE (expr));
3131 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3138 /* Verify if EXPR is a valid GIMPLE reference expression. Returns true
3139 if there is an error, otherwise false. */
3142 verify_types_in_gimple_reference (tree expr)
3144 while (handled_component_p (expr))
3146 tree op = TREE_OPERAND (expr, 0);
3148 if (TREE_CODE (expr) == ARRAY_REF
3149 || TREE_CODE (expr) == ARRAY_RANGE_REF)
3151 if (!is_gimple_val (TREE_OPERAND (expr, 1))
3152 || (TREE_OPERAND (expr, 2)
3153 && !is_gimple_val (TREE_OPERAND (expr, 2)))
3154 || (TREE_OPERAND (expr, 3)
3155 && !is_gimple_val (TREE_OPERAND (expr, 3))))
3157 error ("invalid operands to array reference");
3158 debug_generic_stmt (expr);
3163 /* Verify if the reference array element types are compatible. */
3164 if (TREE_CODE (expr) == ARRAY_REF
3165 && !useless_type_conversion_p (TREE_TYPE (expr),
3166 TREE_TYPE (TREE_TYPE (op))))
3168 error ("type mismatch in array reference");
3169 debug_generic_stmt (TREE_TYPE (expr));
3170 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3173 if (TREE_CODE (expr) == ARRAY_RANGE_REF
3174 && !useless_type_conversion_p (TREE_TYPE (TREE_TYPE (expr)),
3175 TREE_TYPE (TREE_TYPE (op))))
3177 error ("type mismatch in array range reference");
3178 debug_generic_stmt (TREE_TYPE (TREE_TYPE (expr)));
3179 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3183 if ((TREE_CODE (expr) == REALPART_EXPR
3184 || TREE_CODE (expr) == IMAGPART_EXPR)
3185 && !useless_type_conversion_p (TREE_TYPE (expr),
3186 TREE_TYPE (TREE_TYPE (op))))
3188 error ("type mismatch in real/imagpart reference");
3189 debug_generic_stmt (TREE_TYPE (expr));
3190 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3194 if (TREE_CODE (expr) == COMPONENT_REF
3195 && !useless_type_conversion_p (TREE_TYPE (expr),
3196 TREE_TYPE (TREE_OPERAND (expr, 1))))
3198 error ("type mismatch in component reference");
3199 debug_generic_stmt (TREE_TYPE (expr));
3200 debug_generic_stmt (TREE_TYPE (TREE_OPERAND (expr, 1)));
3204 /* For VIEW_CONVERT_EXPRs which are allowed here, too, there
3205 is nothing to verify. Gross mismatches at most invoke
3206 undefined behavior. */
3207 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR
3208 && !handled_component_p (op))
3214 return verify_types_in_gimple_min_lval (expr);
3217 /* Returns true if there is one pointer type in TYPE_POINTER_TO (SRC_OBJ)
3218 list of pointer-to types that is trivially convertible to DEST. */
3221 one_pointer_to_useless_type_conversion_p (tree dest, tree src_obj)
3225 if (!TYPE_POINTER_TO (src_obj))
3228 for (src = TYPE_POINTER_TO (src_obj); src; src = TYPE_NEXT_PTR_TO (src))
3229 if (useless_type_conversion_p (dest, src))
3235 /* Return true if TYPE1 is a fixed-point type and if conversions to and
3236 from TYPE2 can be handled by FIXED_CONVERT_EXPR. */
3239 valid_fixed_convert_types_p (tree type1, tree type2)
3241 return (FIXED_POINT_TYPE_P (type1)
3242 && (INTEGRAL_TYPE_P (type2)
3243 || SCALAR_FLOAT_TYPE_P (type2)
3244 || FIXED_POINT_TYPE_P (type2)));
3247 /* Verify the contents of a GIMPLE_CALL STMT. Returns true when there
3248 is a problem, otherwise false. */
3251 verify_gimple_call (gimple stmt)
3253 tree fn = gimple_call_fn (stmt);
3256 if (!POINTER_TYPE_P (TREE_TYPE (fn))
3257 || (TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != FUNCTION_TYPE
3258 && TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != METHOD_TYPE))
3260 error ("non-function in gimple call");
3264 if (gimple_call_lhs (stmt)
3265 && !is_gimple_lvalue (gimple_call_lhs (stmt)))
3267 error ("invalid LHS in gimple call");
3271 fntype = TREE_TYPE (TREE_TYPE (fn));
3272 if (gimple_call_lhs (stmt)
3273 && !useless_type_conversion_p (TREE_TYPE (gimple_call_lhs (stmt)),
3275 /* ??? At least C++ misses conversions at assignments from
3276 void * call results.
3277 ??? Java is completely off. Especially with functions
3278 returning java.lang.Object.
3279 For now simply allow arbitrary pointer type conversions. */
3280 && !(POINTER_TYPE_P (TREE_TYPE (gimple_call_lhs (stmt)))
3281 && POINTER_TYPE_P (TREE_TYPE (fntype))))
3283 error ("invalid conversion in gimple call");
3284 debug_generic_stmt (TREE_TYPE (gimple_call_lhs (stmt)));
3285 debug_generic_stmt (TREE_TYPE (fntype));
3289 /* ??? The C frontend passes unpromoted arguments in case it
3290 didn't see a function declaration before the call. So for now
3291 leave the call arguments unverified. Once we gimplify
3292 unit-at-a-time we have a chance to fix this. */
3297 /* Verifies the gimple comparison with the result type TYPE and
3298 the operands OP0 and OP1. */
3301 verify_gimple_comparison (tree type, tree op0, tree op1)
3303 tree op0_type = TREE_TYPE (op0);
3304 tree op1_type = TREE_TYPE (op1);
3306 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3308 error ("invalid operands in gimple comparison");
3312 /* For comparisons we do not have the operations type as the
3313 effective type the comparison is carried out in. Instead
3314 we require that either the first operand is trivially
3315 convertible into the second, or the other way around.
3316 The resulting type of a comparison may be any integral type.
3317 Because we special-case pointers to void we allow
3318 comparisons of pointers with the same mode as well. */
3319 if ((!useless_type_conversion_p (op0_type, op1_type)
3320 && !useless_type_conversion_p (op1_type, op0_type)
3321 && (!POINTER_TYPE_P (op0_type)
3322 || !POINTER_TYPE_P (op1_type)
3323 || TYPE_MODE (op0_type) != TYPE_MODE (op1_type)))
3324 || !INTEGRAL_TYPE_P (type))
3326 error ("type mismatch in comparison expression");
3327 debug_generic_expr (type);
3328 debug_generic_expr (op0_type);
3329 debug_generic_expr (op1_type);
3336 /* Verify a gimple assignment statement STMT with an unary rhs.
3337 Returns true if anything is wrong. */
3340 verify_gimple_assign_unary (gimple stmt)
3342 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3343 tree lhs = gimple_assign_lhs (stmt);
3344 tree lhs_type = TREE_TYPE (lhs);
3345 tree rhs1 = gimple_assign_rhs1 (stmt);
3346 tree rhs1_type = TREE_TYPE (rhs1);
3348 if (!is_gimple_reg (lhs)
3350 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3352 error ("non-register as LHS of unary operation");
3356 if (!is_gimple_val (rhs1))
3358 error ("invalid operand in unary operation");
3362 /* First handle conversions. */
3367 /* Allow conversions between integral types and pointers only if
3368 there is no sign or zero extension involved.
3369 For targets were the precision of sizetype doesn't match that
3370 of pointers we need to allow arbitrary conversions from and
3372 if ((POINTER_TYPE_P (lhs_type)
3373 && INTEGRAL_TYPE_P (rhs1_type)
3374 && (TYPE_PRECISION (lhs_type) >= TYPE_PRECISION (rhs1_type)
3375 || rhs1_type == sizetype))
3376 || (POINTER_TYPE_P (rhs1_type)
3377 && INTEGRAL_TYPE_P (lhs_type)
3378 && (TYPE_PRECISION (rhs1_type) >= TYPE_PRECISION (lhs_type)
3379 || lhs_type == sizetype)))
3382 /* Allow conversion from integer to offset type and vice versa. */
3383 if ((TREE_CODE (lhs_type) == OFFSET_TYPE
3384 && TREE_CODE (rhs1_type) == INTEGER_TYPE)
3385 || (TREE_CODE (lhs_type) == INTEGER_TYPE
3386 && TREE_CODE (rhs1_type) == OFFSET_TYPE))
3389 /* Otherwise assert we are converting between types of the
3391 if (INTEGRAL_TYPE_P (lhs_type) != INTEGRAL_TYPE_P (rhs1_type))
3393 error ("invalid types in nop conversion");
3394 debug_generic_expr (lhs_type);
3395 debug_generic_expr (rhs1_type);
3402 case FIXED_CONVERT_EXPR:
3404 if (!valid_fixed_convert_types_p (lhs_type, rhs1_type)
3405 && !valid_fixed_convert_types_p (rhs1_type, lhs_type))
3407 error ("invalid types in fixed-point conversion");
3408 debug_generic_expr (lhs_type);
3409 debug_generic_expr (rhs1_type);
3418 if (!INTEGRAL_TYPE_P (rhs1_type) || !SCALAR_FLOAT_TYPE_P (lhs_type))
3420 error ("invalid types in conversion to floating point");
3421 debug_generic_expr (lhs_type);
3422 debug_generic_expr (rhs1_type);
3429 case FIX_TRUNC_EXPR:
3431 if (!INTEGRAL_TYPE_P (lhs_type) || !SCALAR_FLOAT_TYPE_P (rhs1_type))
3433 error ("invalid types in conversion to integer");
3434 debug_generic_expr (lhs_type);
3435 debug_generic_expr (rhs1_type);
3442 case VEC_UNPACK_HI_EXPR:
3443 case VEC_UNPACK_LO_EXPR:
3444 case REDUC_MAX_EXPR:
3445 case REDUC_MIN_EXPR:
3446 case REDUC_PLUS_EXPR:
3447 case VEC_UNPACK_FLOAT_HI_EXPR:
3448 case VEC_UNPACK_FLOAT_LO_EXPR:
3452 case TRUTH_NOT_EXPR:
3457 case NON_LVALUE_EXPR:
3465 /* For the remaining codes assert there is no conversion involved. */
3466 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3468 error ("non-trivial conversion in unary operation");
3469 debug_generic_expr (lhs_type);
3470 debug_generic_expr (rhs1_type);
3477 /* Verify a gimple assignment statement STMT with a binary rhs.
3478 Returns true if anything is wrong. */
3481 verify_gimple_assign_binary (gimple stmt)
3483 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3484 tree lhs = gimple_assign_lhs (stmt);
3485 tree lhs_type = TREE_TYPE (lhs);
3486 tree rhs1 = gimple_assign_rhs1 (stmt);
3487 tree rhs1_type = TREE_TYPE (rhs1);
3488 tree rhs2 = gimple_assign_rhs2 (stmt);
3489 tree rhs2_type = TREE_TYPE (rhs2);
3491 if (!is_gimple_reg (lhs)
3493 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3495 error ("non-register as LHS of binary operation");
3499 if (!is_gimple_val (rhs1)
3500 || !is_gimple_val (rhs2))
3502 error ("invalid operands in binary operation");
3506 /* First handle operations that involve different types. */
3511 if (TREE_CODE (lhs_type) != COMPLEX_TYPE
3512 || !(INTEGRAL_TYPE_P (rhs1_type)
3513 || SCALAR_FLOAT_TYPE_P (rhs1_type))
3514 || !(INTEGRAL_TYPE_P (rhs2_type)
3515 || SCALAR_FLOAT_TYPE_P (rhs2_type)))
3517 error ("type mismatch in complex expression");
3518 debug_generic_expr (lhs_type);
3519 debug_generic_expr (rhs1_type);
3520 debug_generic_expr (rhs2_type);
3532 /* Shifts and rotates are ok on integral types, fixed point
3533 types and integer vector types. */
3534 if ((!INTEGRAL_TYPE_P (rhs1_type)
3535 && !FIXED_POINT_TYPE_P (rhs1_type)
3536 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3537 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE))
3538 || (!INTEGRAL_TYPE_P (rhs2_type)
3539 /* Vector shifts of vectors are also ok. */
3540 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3541 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE
3542 && TREE_CODE (rhs2_type) == VECTOR_TYPE
3543 && TREE_CODE (TREE_TYPE (rhs2_type)) == INTEGER_TYPE))
3544 || !useless_type_conversion_p (lhs_type, rhs1_type))
3546 error ("type mismatch in shift expression");
3547 debug_generic_expr (lhs_type);
3548 debug_generic_expr (rhs1_type);
3549 debug_generic_expr (rhs2_type);
3556 case VEC_LSHIFT_EXPR:
3557 case VEC_RSHIFT_EXPR:
3559 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3560 || !(INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))
3561 || FIXED_POINT_TYPE_P (TREE_TYPE (rhs1_type)))
3562 || (!INTEGRAL_TYPE_P (rhs2_type)
3563 && (TREE_CODE (rhs2_type) != VECTOR_TYPE
3564 || !INTEGRAL_TYPE_P (TREE_TYPE (rhs2_type))))
3565 || !useless_type_conversion_p (lhs_type, rhs1_type))
3567 error ("type mismatch in vector shift expression");
3568 debug_generic_expr (lhs_type);
3569 debug_generic_expr (rhs1_type);
3570 debug_generic_expr (rhs2_type);
3579 /* We use regular PLUS_EXPR for vectors.
3580 ??? This just makes the checker happy and may not be what is
3582 if (TREE_CODE (lhs_type) == VECTOR_TYPE
3583 && POINTER_TYPE_P (TREE_TYPE (lhs_type)))
3585 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3586 || TREE_CODE (rhs2_type) != VECTOR_TYPE)
3588 error ("invalid non-vector operands to vector valued plus");
3591 lhs_type = TREE_TYPE (lhs_type);
3592 rhs1_type = TREE_TYPE (rhs1_type);
3593 rhs2_type = TREE_TYPE (rhs2_type);
3594 /* PLUS_EXPR is commutative, so we might end up canonicalizing
3595 the pointer to 2nd place. */
3596 if (POINTER_TYPE_P (rhs2_type))
3598 tree tem = rhs1_type;
3599 rhs1_type = rhs2_type;
3602 goto do_pointer_plus_expr_check;
3608 if (POINTER_TYPE_P (lhs_type)
3609 || POINTER_TYPE_P (rhs1_type)
3610 || POINTER_TYPE_P (rhs2_type))
3612 error ("invalid (pointer) operands to plus/minus");
3616 /* Continue with generic binary expression handling. */
3620 case POINTER_PLUS_EXPR:
3622 do_pointer_plus_expr_check:
3623 if (!POINTER_TYPE_P (rhs1_type)
3624 || !useless_type_conversion_p (lhs_type, rhs1_type)
3625 || !useless_type_conversion_p (sizetype, rhs2_type))
3627 error ("type mismatch in pointer plus expression");
3628 debug_generic_stmt (lhs_type);
3629 debug_generic_stmt (rhs1_type);
3630 debug_generic_stmt (rhs2_type);
3637 case TRUTH_ANDIF_EXPR:
3638 case TRUTH_ORIF_EXPR:
3641 case TRUTH_AND_EXPR:
3643 case TRUTH_XOR_EXPR:
3645 /* We allow any kind of integral typed argument and result. */
3646 if (!INTEGRAL_TYPE_P (rhs1_type)
3647 || !INTEGRAL_TYPE_P (rhs2_type)
3648 || !INTEGRAL_TYPE_P (lhs_type))
3650 error ("type mismatch in binary truth expression");
3651 debug_generic_expr (lhs_type);
3652 debug_generic_expr (rhs1_type);
3653 debug_generic_expr (rhs2_type);
3666 case UNORDERED_EXPR:
3674 /* Comparisons are also binary, but the result type is not
3675 connected to the operand types. */
3676 return verify_gimple_comparison (lhs_type, rhs1, rhs2);
3678 case WIDEN_SUM_EXPR:
3679 case WIDEN_MULT_EXPR:
3680 case VEC_WIDEN_MULT_HI_EXPR:
3681 case VEC_WIDEN_MULT_LO_EXPR:
3682 case VEC_PACK_TRUNC_EXPR:
3683 case VEC_PACK_SAT_EXPR:
3684 case VEC_PACK_FIX_TRUNC_EXPR:
3685 case VEC_EXTRACT_EVEN_EXPR:
3686 case VEC_EXTRACT_ODD_EXPR:
3687 case VEC_INTERLEAVE_HIGH_EXPR:
3688 case VEC_INTERLEAVE_LOW_EXPR:
3693 case TRUNC_DIV_EXPR:
3695 case FLOOR_DIV_EXPR:
3696 case ROUND_DIV_EXPR:
3697 case TRUNC_MOD_EXPR:
3699 case FLOOR_MOD_EXPR:
3700 case ROUND_MOD_EXPR:
3702 case EXACT_DIV_EXPR:
3708 /* Continue with generic binary expression handling. */
3715 if (!useless_type_conversion_p (lhs_type, rhs1_type)
3716 || !useless_type_conversion_p (lhs_type, rhs2_type))
3718 error ("type mismatch in binary expression");
3719 debug_generic_stmt (lhs_type);
3720 debug_generic_stmt (rhs1_type);
3721 debug_generic_stmt (rhs2_type);
3728 /* Verify a gimple assignment statement STMT with a single rhs.
3729 Returns true if anything is wrong. */
3732 verify_gimple_assign_single (gimple stmt)
3734 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3735 tree lhs = gimple_assign_lhs (stmt);
3736 tree lhs_type = TREE_TYPE (lhs);
3737 tree rhs1 = gimple_assign_rhs1 (stmt);
3738 tree rhs1_type = TREE_TYPE (rhs1);
3741 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3743 error ("non-trivial conversion at assignment");
3744 debug_generic_expr (lhs_type);
3745 debug_generic_expr (rhs1_type);
3749 if (handled_component_p (lhs))
3750 res |= verify_types_in_gimple_reference (lhs);
3752 /* Special codes we cannot handle via their class. */
3757 tree op = TREE_OPERAND (rhs1, 0);
3758 if (!is_gimple_addressable (op))
3760 error ("invalid operand in unary expression");
3764 if (!one_pointer_to_useless_type_conversion_p (lhs_type,
3767 error ("type mismatch in address expression");
3768 debug_generic_stmt (lhs_type);
3769 debug_generic_stmt (TYPE_POINTER_TO (TREE_TYPE (op)));
3773 return verify_types_in_gimple_reference (op);
3780 case ALIGN_INDIRECT_REF:
3781 case MISALIGNED_INDIRECT_REF:
3783 case ARRAY_RANGE_REF:
3784 case VIEW_CONVERT_EXPR:
3787 case TARGET_MEM_REF:
3788 if (!is_gimple_reg (lhs)
3789 && is_gimple_reg_type (TREE_TYPE (lhs)))
3791 error ("invalid rhs for gimple memory store");
3792 debug_generic_stmt (lhs);
3793 debug_generic_stmt (rhs1);
3796 return res || verify_types_in_gimple_reference (rhs1);
3808 /* tcc_declaration */
3813 if (!is_gimple_reg (lhs)
3814 && !is_gimple_reg (rhs1)
3815 && is_gimple_reg_type (TREE_TYPE (lhs)))
3817 error ("invalid rhs for gimple memory store");
3818 debug_generic_stmt (lhs);
3819 debug_generic_stmt (rhs1);
3828 case WITH_SIZE_EXPR:
3831 case POLYNOMIAL_CHREC:
3834 case REALIGN_LOAD_EXPR:
3844 /* Verify the contents of a GIMPLE_ASSIGN STMT. Returns true when there
3845 is a problem, otherwise false. */
3848 verify_gimple_assign (gimple stmt)
3850 switch (gimple_assign_rhs_class (stmt))
3852 case GIMPLE_SINGLE_RHS:
3853 return verify_gimple_assign_single (stmt);
3855 case GIMPLE_UNARY_RHS:
3856 return verify_gimple_assign_unary (stmt);
3858 case GIMPLE_BINARY_RHS:
3859 return verify_gimple_assign_binary (stmt);
3866 /* Verify the contents of a GIMPLE_RETURN STMT. Returns true when there
3867 is a problem, otherwise false. */
3870 verify_gimple_return (gimple stmt)
3872 tree op = gimple_return_retval (stmt);
3873 tree restype = TREE_TYPE (TREE_TYPE (cfun->decl));
3875 /* We cannot test for present return values as we do not fix up missing
3876 return values from the original source. */
3880 if (!is_gimple_val (op)
3881 && TREE_CODE (op) != RESULT_DECL)
3883 error ("invalid operand in return statement");
3884 debug_generic_stmt (op);
3888 if (!useless_type_conversion_p (restype, TREE_TYPE (op))
3889 /* ??? With C++ we can have the situation that the result
3890 decl is a reference type while the return type is an aggregate. */
3891 && !(TREE_CODE (op) == RESULT_DECL
3892 && TREE_CODE (TREE_TYPE (op)) == REFERENCE_TYPE
3893 && useless_type_conversion_p (restype, TREE_TYPE (TREE_TYPE (op)))))
3895 error ("invalid conversion in return statement");
3896 debug_generic_stmt (restype);
3897 debug_generic_stmt (TREE_TYPE (op));
3905 /* Verify the contents of a GIMPLE_GOTO STMT. Returns true when there
3906 is a problem, otherwise false. */
3909 verify_gimple_goto (gimple stmt)
3911 tree dest = gimple_goto_dest (stmt);
3913 /* ??? We have two canonical forms of direct goto destinations, a
3914 bare LABEL_DECL and an ADDR_EXPR of a LABEL_DECL. */
3915 if (TREE_CODE (dest) != LABEL_DECL
3916 && (!is_gimple_val (dest)
3917 || !POINTER_TYPE_P (TREE_TYPE (dest))))
3919 error ("goto destination is neither a label nor a pointer");
3926 /* Verify the contents of a GIMPLE_SWITCH STMT. Returns true when there
3927 is a problem, otherwise false. */
3930 verify_gimple_switch (gimple stmt)
3932 if (!is_gimple_val (gimple_switch_index (stmt)))
3934 error ("invalid operand to switch statement");
3935 debug_generic_stmt (gimple_switch_index (stmt));
3943 /* Verify the contents of a GIMPLE_PHI. Returns true if there is a problem,
3944 and false otherwise. */
3947 verify_gimple_phi (gimple stmt)
3949 tree type = TREE_TYPE (gimple_phi_result (stmt));
3952 if (!is_gimple_variable (gimple_phi_result (stmt)))
3954 error ("Invalid PHI result");
3958 for (i = 0; i < gimple_phi_num_args (stmt); i++)
3960 tree arg = gimple_phi_arg_def (stmt, i);
3961 if ((is_gimple_reg (gimple_phi_result (stmt))
3962 && !is_gimple_val (arg))
3963 || (!is_gimple_reg (gimple_phi_result (stmt))
3964 && !is_gimple_addressable (arg)))
3966 error ("Invalid PHI argument");
3967 debug_generic_stmt (arg);
3970 if (!useless_type_conversion_p (type, TREE_TYPE (arg)))
3972 error ("Incompatible types in PHI argument %u", i);
3973 debug_generic_stmt (type);
3974 debug_generic_stmt (TREE_TYPE (arg));
3983 /* Verify the GIMPLE statement STMT. Returns true if there is an
3984 error, otherwise false. */
3987 verify_types_in_gimple_stmt (gimple stmt)
3989 if (is_gimple_omp (stmt))
3991 /* OpenMP directives are validated by the FE and never operated
3992 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
3993 non-gimple expressions when the main index variable has had
3994 its address taken. This does not affect the loop itself
3995 because the header of an GIMPLE_OMP_FOR is merely used to determine
3996 how to setup the parallel iteration. */
4000 switch (gimple_code (stmt))
4003 return verify_gimple_assign (stmt);
4006 return TREE_CODE (gimple_label_label (stmt)) != LABEL_DECL;
4009 return verify_gimple_call (stmt);
4012 return verify_gimple_comparison (boolean_type_node,
4013 gimple_cond_lhs (stmt),
4014 gimple_cond_rhs (stmt));
4017 return verify_gimple_goto (stmt);
4020 return verify_gimple_switch (stmt);
4023 return verify_gimple_return (stmt);
4028 case GIMPLE_CHANGE_DYNAMIC_TYPE:
4029 return (!is_gimple_val (gimple_cdt_location (stmt))
4030 || !POINTER_TYPE_P (TREE_TYPE (gimple_cdt_location (stmt))));
4033 return verify_gimple_phi (stmt);
4035 /* Tuples that do not have tree operands. */
4038 case GIMPLE_PREDICT:
4046 /* Verify the GIMPLE statements inside the sequence STMTS. */
4049 verify_types_in_gimple_seq_2 (gimple_seq stmts)
4051 gimple_stmt_iterator ittr;
4054 for (ittr = gsi_start (stmts); !gsi_end_p (ittr); gsi_next (&ittr))
4056 gimple stmt = gsi_stmt (ittr);
4058 switch (gimple_code (stmt))
4061 err |= verify_types_in_gimple_seq_2 (gimple_bind_body (stmt));
4065 err |= verify_types_in_gimple_seq_2 (gimple_try_eval (stmt));
4066 err |= verify_types_in_gimple_seq_2 (gimple_try_cleanup (stmt));
4069 case GIMPLE_EH_FILTER:
4070 err |= verify_types_in_gimple_seq_2 (gimple_eh_filter_failure (stmt));
4074 err |= verify_types_in_gimple_seq_2 (gimple_catch_handler (stmt));
4079 bool err2 = verify_types_in_gimple_stmt (stmt);
4081 debug_gimple_stmt (stmt);
4091 /* Verify the GIMPLE statements inside the statement list STMTS. */
4094 verify_types_in_gimple_seq (gimple_seq stmts)
4096 if (verify_types_in_gimple_seq_2 (stmts))
4097 internal_error ("verify_gimple failed");
4101 /* Verify STMT, return true if STMT is not in GIMPLE form.
4102 TODO: Implement type checking. */
4105 verify_stmt (gimple_stmt_iterator *gsi)
4108 struct walk_stmt_info wi;
4109 bool last_in_block = gsi_one_before_end_p (*gsi);
4110 gimple stmt = gsi_stmt (*gsi);
4112 if (is_gimple_omp (stmt))
4114 /* OpenMP directives are validated by the FE and never operated
4115 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4116 non-gimple expressions when the main index variable has had
4117 its address taken. This does not affect the loop itself
4118 because the header of an GIMPLE_OMP_FOR is merely used to determine
4119 how to setup the parallel iteration. */
4123 /* FIXME. The C frontend passes unpromoted arguments in case it
4124 didn't see a function declaration before the call. */
4125 if (is_gimple_call (stmt))
4129 if (!is_gimple_call_addr (gimple_call_fn (stmt)))
4131 error ("invalid function in call statement");
4135 decl = gimple_call_fndecl (stmt);
4137 && TREE_CODE (decl) == FUNCTION_DECL
4138 && DECL_LOOPING_CONST_OR_PURE_P (decl)
4139 && (!DECL_PURE_P (decl))
4140 && (!TREE_READONLY (decl)))
4142 error ("invalid pure const state for function");
4147 memset (&wi, 0, sizeof (wi));
4148 addr = walk_gimple_op (gsi_stmt (*gsi), verify_expr, &wi);
4151 debug_generic_expr (addr);
4152 inform (input_location, "in statement");
4153 debug_gimple_stmt (stmt);
4157 /* If the statement is marked as part of an EH region, then it is
4158 expected that the statement could throw. Verify that when we
4159 have optimizations that simplify statements such that we prove
4160 that they cannot throw, that we update other data structures
4162 if (lookup_stmt_eh_region (stmt) >= 0)
4164 /* During IPA passes, ipa-pure-const sets nothrow flags on calls
4165 and they are updated on statements only after fixup_cfg
4166 is executed at beggining of expansion stage. */
4167 if (!stmt_could_throw_p (stmt) && cgraph_state != CGRAPH_STATE_IPA_SSA)
4169 error ("statement marked for throw, but doesn%'t");
4172 if (!last_in_block && stmt_can_throw_internal (stmt))
4174 error ("statement marked for throw in middle of block");
4182 debug_gimple_stmt (stmt);
4187 /* Return true when the T can be shared. */
4190 tree_node_can_be_shared (tree t)
4192 if (IS_TYPE_OR_DECL_P (t)
4193 || is_gimple_min_invariant (t)
4194 || TREE_CODE (t) == SSA_NAME
4195 || t == error_mark_node
4196 || TREE_CODE (t) == IDENTIFIER_NODE)
4199 if (TREE_CODE (t) == CASE_LABEL_EXPR)
4202 while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4203 && is_gimple_min_invariant (TREE_OPERAND (t, 1)))
4204 || TREE_CODE (t) == COMPONENT_REF
4205 || TREE_CODE (t) == REALPART_EXPR
4206 || TREE_CODE (t) == IMAGPART_EXPR)
4207 t = TREE_OPERAND (t, 0);
4216 /* Called via walk_gimple_stmt. Verify tree sharing. */
4219 verify_node_sharing (tree *tp, int *walk_subtrees, void *data)
4221 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
4222 struct pointer_set_t *visited = (struct pointer_set_t *) wi->info;
4224 if (tree_node_can_be_shared (*tp))
4226 *walk_subtrees = false;
4230 if (pointer_set_insert (visited, *tp))
4237 static bool eh_error_found;
4239 verify_eh_throw_stmt_node (void **slot, void *data)
4241 struct throw_stmt_node *node = (struct throw_stmt_node *)*slot;
4242 struct pointer_set_t *visited = (struct pointer_set_t *) data;
4244 if (!pointer_set_contains (visited, node->stmt))
4246 error ("Dead STMT in EH table");
4247 debug_gimple_stmt (node->stmt);
4248 eh_error_found = true;
4254 /* Verify the GIMPLE statements in every basic block. */
4260 gimple_stmt_iterator gsi;
4262 struct pointer_set_t *visited, *visited_stmts;
4264 struct walk_stmt_info wi;
4266 timevar_push (TV_TREE_STMT_VERIFY);
4267 visited = pointer_set_create ();
4268 visited_stmts = pointer_set_create ();
4270 memset (&wi, 0, sizeof (wi));
4271 wi.info = (void *) visited;
4278 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4280 phi = gsi_stmt (gsi);
4281 pointer_set_insert (visited_stmts, phi);
4282 if (gimple_bb (phi) != bb)
4284 error ("gimple_bb (phi) is set to a wrong basic block");
4288 for (i = 0; i < gimple_phi_num_args (phi); i++)
4290 tree t = gimple_phi_arg_def (phi, i);
4295 error ("missing PHI def");
4296 debug_gimple_stmt (phi);
4300 /* Addressable variables do have SSA_NAMEs but they
4301 are not considered gimple values. */
4302 else if (TREE_CODE (t) != SSA_NAME
4303 && TREE_CODE (t) != FUNCTION_DECL
4304 && !is_gimple_min_invariant (t))
4306 error ("PHI argument is not a GIMPLE value");
4307 debug_gimple_stmt (phi);
4308 debug_generic_expr (t);
4312 addr = walk_tree (&t, verify_node_sharing, visited, NULL);
4315 error ("incorrect sharing of tree nodes");
4316 debug_gimple_stmt (phi);
4317 debug_generic_expr (addr);
4322 #ifdef ENABLE_TYPES_CHECKING
4323 if (verify_gimple_phi (phi))
4325 debug_gimple_stmt (phi);
4331 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); )
4333 gimple stmt = gsi_stmt (gsi);
4335 if (gimple_code (stmt) == GIMPLE_WITH_CLEANUP_EXPR
4336 || gimple_code (stmt) == GIMPLE_BIND)
4338 error ("invalid GIMPLE statement");
4339 debug_gimple_stmt (stmt);
4343 pointer_set_insert (visited_stmts, stmt);
4345 if (gimple_bb (stmt) != bb)
4347 error ("gimple_bb (stmt) is set to a wrong basic block");
4351 if (gimple_code (stmt) == GIMPLE_LABEL)
4353 tree decl = gimple_label_label (stmt);
4354 int uid = LABEL_DECL_UID (decl);
4357 || VEC_index (basic_block, label_to_block_map, uid) != bb)
4359 error ("incorrect entry in label_to_block_map.\n");
4364 err |= verify_stmt (&gsi);
4366 #ifdef ENABLE_TYPES_CHECKING
4367 if (verify_types_in_gimple_stmt (gsi_stmt (gsi)))
4369 debug_gimple_stmt (stmt);
4373 addr = walk_gimple_op (gsi_stmt (gsi), verify_node_sharing, &wi);
4376 error ("incorrect sharing of tree nodes");
4377 debug_gimple_stmt (stmt);
4378 debug_generic_expr (addr);
4385 eh_error_found = false;
4386 if (get_eh_throw_stmt_table (cfun))
4387 htab_traverse (get_eh_throw_stmt_table (cfun),
4388 verify_eh_throw_stmt_node,
4391 if (err | eh_error_found)
4392 internal_error ("verify_stmts failed");
4394 pointer_set_destroy (visited);
4395 pointer_set_destroy (visited_stmts);
4396 verify_histograms ();
4397 timevar_pop (TV_TREE_STMT_VERIFY);
4401 /* Verifies that the flow information is OK. */
4404 gimple_verify_flow_info (void)
4408 gimple_stmt_iterator gsi;
4413 if (ENTRY_BLOCK_PTR->il.gimple)
4415 error ("ENTRY_BLOCK has IL associated with it");
4419 if (EXIT_BLOCK_PTR->il.gimple)
4421 error ("EXIT_BLOCK has IL associated with it");
4425 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4426 if (e->flags & EDGE_FALLTHRU)
4428 error ("fallthru to exit from bb %d", e->src->index);
4434 bool found_ctrl_stmt = false;
4438 /* Skip labels on the start of basic block. */
4439 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4442 gimple prev_stmt = stmt;
4444 stmt = gsi_stmt (gsi);
4446 if (gimple_code (stmt) != GIMPLE_LABEL)
4449 label = gimple_label_label (stmt);
4450 if (prev_stmt && DECL_NONLOCAL (label))
4452 error ("nonlocal label ");
4453 print_generic_expr (stderr, label, 0);
4454 fprintf (stderr, " is not first in a sequence of labels in bb %d",
4459 if (label_to_block (label) != bb)
4462 print_generic_expr (stderr, label, 0);
4463 fprintf (stderr, " to block does not match in bb %d",
4468 if (decl_function_context (label) != current_function_decl)
4471 print_generic_expr (stderr, label, 0);
4472 fprintf (stderr, " has incorrect context in bb %d",
4478 /* Verify that body of basic block BB is free of control flow. */
4479 for (; !gsi_end_p (gsi); gsi_next (&gsi))
4481 gimple stmt = gsi_stmt (gsi);
4483 if (found_ctrl_stmt)
4485 error ("control flow in the middle of basic block %d",
4490 if (stmt_ends_bb_p (stmt))
4491 found_ctrl_stmt = true;
4493 if (gimple_code (stmt) == GIMPLE_LABEL)
4496 print_generic_expr (stderr, gimple_label_label (stmt), 0);
4497 fprintf (stderr, " in the middle of basic block %d", bb->index);
4502 gsi = gsi_last_bb (bb);
4503 if (gsi_end_p (gsi))
4506 stmt = gsi_stmt (gsi);
4508 err |= verify_eh_edges (stmt);
4510 if (is_ctrl_stmt (stmt))
4512 FOR_EACH_EDGE (e, ei, bb->succs)
4513 if (e->flags & EDGE_FALLTHRU)
4515 error ("fallthru edge after a control statement in bb %d",
4521 if (gimple_code (stmt) != GIMPLE_COND)
4523 /* Verify that there are no edges with EDGE_TRUE/FALSE_FLAG set
4524 after anything else but if statement. */
4525 FOR_EACH_EDGE (e, ei, bb->succs)
4526 if (e->flags & (EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))
4528 error ("true/false edge after a non-GIMPLE_COND in bb %d",
4534 switch (gimple_code (stmt))
4541 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
4545 || !(true_edge->flags & EDGE_TRUE_VALUE)
4546 || !(false_edge->flags & EDGE_FALSE_VALUE)
4547 || (true_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4548 || (false_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4549 || EDGE_COUNT (bb->succs) >= 3)
4551 error ("wrong outgoing edge flags at end of bb %d",
4559 if (simple_goto_p (stmt))
4561 error ("explicit goto at end of bb %d", bb->index);
4566 /* FIXME. We should double check that the labels in the
4567 destination blocks have their address taken. */
4568 FOR_EACH_EDGE (e, ei, bb->succs)
4569 if ((e->flags & (EDGE_FALLTHRU | EDGE_TRUE_VALUE
4570 | EDGE_FALSE_VALUE))
4571 || !(e->flags & EDGE_ABNORMAL))
4573 error ("wrong outgoing edge flags at end of bb %d",
4581 if (!single_succ_p (bb)
4582 || (single_succ_edge (bb)->flags
4583 & (EDGE_FALLTHRU | EDGE_ABNORMAL
4584 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4586 error ("wrong outgoing edge flags at end of bb %d", bb->index);
4589 if (single_succ (bb) != EXIT_BLOCK_PTR)
4591 error ("return edge does not point to exit in bb %d",
4603 n = gimple_switch_num_labels (stmt);
4605 /* Mark all the destination basic blocks. */
4606 for (i = 0; i < n; ++i)
4608 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4609 basic_block label_bb = label_to_block (lab);
4610 gcc_assert (!label_bb->aux || label_bb->aux == (void *)1);
4611 label_bb->aux = (void *)1;
4614 /* Verify that the case labels are sorted. */
4615 prev = gimple_switch_label (stmt, 0);
4616 for (i = 1; i < n; ++i)
4618 tree c = gimple_switch_label (stmt, i);
4621 error ("found default case not at the start of "
4627 && !tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c)))
4629 error ("case labels not sorted: ");
4630 print_generic_expr (stderr, prev, 0);
4631 fprintf (stderr," is greater than ");
4632 print_generic_expr (stderr, c, 0);
4633 fprintf (stderr," but comes before it.\n");
4638 /* VRP will remove the default case if it can prove it will
4639 never be executed. So do not verify there always exists
4640 a default case here. */
4642 FOR_EACH_EDGE (e, ei, bb->succs)
4646 error ("extra outgoing edge %d->%d",
4647 bb->index, e->dest->index);
4651 e->dest->aux = (void *)2;
4652 if ((e->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL
4653 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4655 error ("wrong outgoing edge flags at end of bb %d",
4661 /* Check that we have all of them. */
4662 for (i = 0; i < n; ++i)
4664 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4665 basic_block label_bb = label_to_block (lab);
4667 if (label_bb->aux != (void *)2)
4669 error ("missing edge %i->%i", bb->index, label_bb->index);
4674 FOR_EACH_EDGE (e, ei, bb->succs)
4675 e->dest->aux = (void *)0;
4682 if (dom_info_state (CDI_DOMINATORS) >= DOM_NO_FAST_QUERY)
4683 verify_dominators (CDI_DOMINATORS);
4689 /* Updates phi nodes after creating a forwarder block joined
4690 by edge FALLTHRU. */
4693 gimple_make_forwarder_block (edge fallthru)
4697 basic_block dummy, bb;
4699 gimple_stmt_iterator gsi;
4701 dummy = fallthru->src;
4702 bb = fallthru->dest;
4704 if (single_pred_p (bb))
4707 /* If we redirected a branch we must create new PHI nodes at the
4709 for (gsi = gsi_start_phis (dummy); !gsi_end_p (gsi); gsi_next (&gsi))
4711 gimple phi, new_phi;
4713 phi = gsi_stmt (gsi);
4714 var = gimple_phi_result (phi);
4715 new_phi = create_phi_node (var, bb);
4716 SSA_NAME_DEF_STMT (var) = new_phi;
4717 gimple_phi_set_result (phi, make_ssa_name (SSA_NAME_VAR (var), phi));
4718 add_phi_arg (new_phi, gimple_phi_result (phi), fallthru);
4721 /* Add the arguments we have stored on edges. */
4722 FOR_EACH_EDGE (e, ei, bb->preds)
4727 flush_pending_stmts (e);
4732 /* Return a non-special label in the head of basic block BLOCK.
4733 Create one if it doesn't exist. */
4736 gimple_block_label (basic_block bb)
4738 gimple_stmt_iterator i, s = gsi_start_bb (bb);
4743 for (i = s; !gsi_end_p (i); first = false, gsi_next (&i))
4745 stmt = gsi_stmt (i);
4746 if (gimple_code (stmt) != GIMPLE_LABEL)
4748 label = gimple_label_label (stmt);
4749 if (!DECL_NONLOCAL (label))
4752 gsi_move_before (&i, &s);
4757 label = create_artificial_label ();
4758 stmt = gimple_build_label (label);
4759 gsi_insert_before (&s, stmt, GSI_NEW_STMT);
4764 /* Attempt to perform edge redirection by replacing a possibly complex
4765 jump instruction by a goto or by removing the jump completely.
4766 This can apply only if all edges now point to the same block. The
4767 parameters and return values are equivalent to
4768 redirect_edge_and_branch. */
4771 gimple_try_redirect_by_replacing_jump (edge e, basic_block target)
4773 basic_block src = e->src;
4774 gimple_stmt_iterator i;
4777 /* We can replace or remove a complex jump only when we have exactly
4779 if (EDGE_COUNT (src->succs) != 2
4780 /* Verify that all targets will be TARGET. Specifically, the
4781 edge that is not E must also go to TARGET. */
4782 || EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)
4785 i = gsi_last_bb (src);
4789 stmt = gsi_stmt (i);
4791 if (gimple_code (stmt) == GIMPLE_COND || gimple_code (stmt) == GIMPLE_SWITCH)
4793 gsi_remove (&i, true);
4794 e = ssa_redirect_edge (e, target);
4795 e->flags = EDGE_FALLTHRU;
4803 /* Redirect E to DEST. Return NULL on failure. Otherwise, return the
4804 edge representing the redirected branch. */
4807 gimple_redirect_edge_and_branch (edge e, basic_block dest)
4809 basic_block bb = e->src;
4810 gimple_stmt_iterator gsi;
4814 if (e->flags & EDGE_ABNORMAL)
4817 if (e->src != ENTRY_BLOCK_PTR
4818 && (ret = gimple_try_redirect_by_replacing_jump (e, dest)))
4821 if (e->dest == dest)
4824 if (e->flags & EDGE_EH)
4825 return redirect_eh_edge (e, dest);
4827 gsi = gsi_last_bb (bb);
4828 stmt = gsi_end_p (gsi) ? NULL : gsi_stmt (gsi);
4830 switch (stmt ? gimple_code (stmt) : ERROR_MARK)
4833 /* For COND_EXPR, we only need to redirect the edge. */
4837 /* No non-abnormal edges should lead from a non-simple goto, and
4838 simple ones should be represented implicitly. */
4843 tree label = gimple_block_label (dest);
4844 tree cases = get_cases_for_edge (e, stmt);
4846 /* If we have a list of cases associated with E, then use it
4847 as it's a lot faster than walking the entire case vector. */
4850 edge e2 = find_edge (e->src, dest);
4857 CASE_LABEL (cases) = label;
4858 cases = TREE_CHAIN (cases);
4861 /* If there was already an edge in the CFG, then we need
4862 to move all the cases associated with E to E2. */
4865 tree cases2 = get_cases_for_edge (e2, stmt);
4867 TREE_CHAIN (last) = TREE_CHAIN (cases2);
4868 TREE_CHAIN (cases2) = first;
4873 size_t i, n = gimple_switch_num_labels (stmt);
4875 for (i = 0; i < n; i++)
4877 tree elt = gimple_switch_label (stmt, i);
4878 if (label_to_block (CASE_LABEL (elt)) == e->dest)
4879 CASE_LABEL (elt) = label;
4887 gsi_remove (&gsi, true);
4888 e->flags |= EDGE_FALLTHRU;
4891 case GIMPLE_OMP_RETURN:
4892 case GIMPLE_OMP_CONTINUE:
4893 case GIMPLE_OMP_SECTIONS_SWITCH:
4894 case GIMPLE_OMP_FOR:
4895 /* The edges from OMP constructs can be simply redirected. */
4899 /* Otherwise it must be a fallthru edge, and we don't need to
4900 do anything besides redirecting it. */
4901 gcc_assert (e->flags & EDGE_FALLTHRU);
4905 /* Update/insert PHI nodes as necessary. */
4907 /* Now update the edges in the CFG. */
4908 e = ssa_redirect_edge (e, dest);
4913 /* Returns true if it is possible to remove edge E by redirecting
4914 it to the destination of the other edge from E->src. */
4917 gimple_can_remove_branch_p (const_edge e)
4919 if (e->flags & (EDGE_ABNORMAL | EDGE_EH))
4925 /* Simple wrapper, as we can always redirect fallthru edges. */
4928 gimple_redirect_edge_and_branch_force (edge e, basic_block dest)
4930 e = gimple_redirect_edge_and_branch (e, dest);
4937 /* Splits basic block BB after statement STMT (but at least after the
4938 labels). If STMT is NULL, BB is split just after the labels. */
4941 gimple_split_block (basic_block bb, void *stmt)
4943 gimple_stmt_iterator gsi;
4944 gimple_stmt_iterator gsi_tgt;
4951 new_bb = create_empty_bb (bb);
4953 /* Redirect the outgoing edges. */
4954 new_bb->succs = bb->succs;
4956 FOR_EACH_EDGE (e, ei, new_bb->succs)
4959 if (stmt && gimple_code ((gimple) stmt) == GIMPLE_LABEL)
4962 /* Move everything from GSI to the new basic block. */
4963 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4965 act = gsi_stmt (gsi);
4966 if (gimple_code (act) == GIMPLE_LABEL)
4979 if (gsi_end_p (gsi))
4982 /* Split the statement list - avoid re-creating new containers as this
4983 brings ugly quadratic memory consumption in the inliner.
4984 (We are still quadratic since we need to update stmt BB pointers,
4986 list = gsi_split_seq_before (&gsi);
4987 set_bb_seq (new_bb, list);
4988 for (gsi_tgt = gsi_start (list);
4989 !gsi_end_p (gsi_tgt); gsi_next (&gsi_tgt))
4990 gimple_set_bb (gsi_stmt (gsi_tgt), new_bb);
4996 /* Moves basic block BB after block AFTER. */
4999 gimple_move_block_after (basic_block bb, basic_block after)
5001 if (bb->prev_bb == after)
5005 link_block (bb, after);
5011 /* Return true if basic_block can be duplicated. */
5014 gimple_can_duplicate_bb_p (const_basic_block bb ATTRIBUTE_UNUSED)
5019 /* Create a duplicate of the basic block BB. NOTE: This does not
5020 preserve SSA form. */
5023 gimple_duplicate_bb (basic_block bb)
5026 gimple_stmt_iterator gsi, gsi_tgt;
5027 gimple_seq phis = phi_nodes (bb);
5028 gimple phi, stmt, copy;
5030 new_bb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb);
5032 /* Copy the PHI nodes. We ignore PHI node arguments here because
5033 the incoming edges have not been setup yet. */
5034 for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
5036 phi = gsi_stmt (gsi);
5037 copy = create_phi_node (gimple_phi_result (phi), new_bb);
5038 create_new_def_for (gimple_phi_result (copy), copy,
5039 gimple_phi_result_ptr (copy));
5042 gsi_tgt = gsi_start_bb (new_bb);
5043 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5045 def_operand_p def_p;
5046 ssa_op_iter op_iter;
5049 stmt = gsi_stmt (gsi);
5050 if (gimple_code (stmt) == GIMPLE_LABEL)
5053 /* Create a new copy of STMT and duplicate STMT's virtual
5055 copy = gimple_copy (stmt);
5056 gsi_insert_after (&gsi_tgt, copy, GSI_NEW_STMT);
5057 region = lookup_stmt_eh_region (stmt);
5059 add_stmt_to_eh_region (copy, region);
5060 gimple_duplicate_stmt_histograms (cfun, copy, cfun, stmt);
5062 /* Create new names for all the definitions created by COPY and
5063 add replacement mappings for each new name. */
5064 FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS)
5065 create_new_def_for (DEF_FROM_PTR (def_p), copy, def_p);
5071 /* Adds phi node arguments for edge E_COPY after basic block duplication. */
5074 add_phi_args_after_copy_edge (edge e_copy)
5076 basic_block bb, bb_copy = e_copy->src, dest;
5079 gimple phi, phi_copy;
5081 gimple_stmt_iterator psi, psi_copy;
5083 if (gimple_seq_empty_p (phi_nodes (e_copy->dest)))
5086 bb = bb_copy->flags & BB_DUPLICATED ? get_bb_original (bb_copy) : bb_copy;
5088 if (e_copy->dest->flags & BB_DUPLICATED)
5089 dest = get_bb_original (e_copy->dest);
5091 dest = e_copy->dest;
5093 e = find_edge (bb, dest);
5096 /* During loop unrolling the target of the latch edge is copied.
5097 In this case we are not looking for edge to dest, but to
5098 duplicated block whose original was dest. */
5099 FOR_EACH_EDGE (e, ei, bb->succs)
5101 if ((e->dest->flags & BB_DUPLICATED)
5102 && get_bb_original (e->dest) == dest)
5106 gcc_assert (e != NULL);
5109 for (psi = gsi_start_phis (e->dest),
5110 psi_copy = gsi_start_phis (e_copy->dest);
5112 gsi_next (&psi), gsi_next (&psi_copy))
5114 phi = gsi_stmt (psi);
5115 phi_copy = gsi_stmt (psi_copy);
5116 def = PHI_ARG_DEF_FROM_EDGE (phi, e);
5117 add_phi_arg (phi_copy, def, e_copy);
5122 /* Basic block BB_COPY was created by code duplication. Add phi node
5123 arguments for edges going out of BB_COPY. The blocks that were
5124 duplicated have BB_DUPLICATED set. */
5127 add_phi_args_after_copy_bb (basic_block bb_copy)
5132 FOR_EACH_EDGE (e_copy, ei, bb_copy->succs)
5134 add_phi_args_after_copy_edge (e_copy);
5138 /* Blocks in REGION_COPY array of length N_REGION were created by
5139 duplication of basic blocks. Add phi node arguments for edges
5140 going from these blocks. If E_COPY is not NULL, also add
5141 phi node arguments for its destination.*/
5144 add_phi_args_after_copy (basic_block *region_copy, unsigned n_region,
5149 for (i = 0; i < n_region; i++)
5150 region_copy[i]->flags |= BB_DUPLICATED;
5152 for (i = 0; i < n_region; i++)
5153 add_phi_args_after_copy_bb (region_copy[i]);
5155 add_phi_args_after_copy_edge (e_copy);
5157 for (i = 0; i < n_region; i++)
5158 region_copy[i]->flags &= ~BB_DUPLICATED;
5161 /* Duplicates a REGION (set of N_REGION basic blocks) with just a single
5162 important exit edge EXIT. By important we mean that no SSA name defined
5163 inside region is live over the other exit edges of the region. All entry
5164 edges to the region must go to ENTRY->dest. The edge ENTRY is redirected
5165 to the duplicate of the region. SSA form, dominance and loop information
5166 is updated. The new basic blocks are stored to REGION_COPY in the same
5167 order as they had in REGION, provided that REGION_COPY is not NULL.
5168 The function returns false if it is unable to copy the region,
5172 gimple_duplicate_sese_region (edge entry, edge exit,
5173 basic_block *region, unsigned n_region,
5174 basic_block *region_copy)
5177 bool free_region_copy = false, copying_header = false;
5178 struct loop *loop = entry->dest->loop_father;
5180 VEC (basic_block, heap) *doms;
5182 int total_freq = 0, entry_freq = 0;
5183 gcov_type total_count = 0, entry_count = 0;
5185 if (!can_copy_bbs_p (region, n_region))
5188 /* Some sanity checking. Note that we do not check for all possible
5189 missuses of the functions. I.e. if you ask to copy something weird,
5190 it will work, but the state of structures probably will not be
5192 for (i = 0; i < n_region; i++)
5194 /* We do not handle subloops, i.e. all the blocks must belong to the
5196 if (region[i]->loop_father != loop)
5199 if (region[i] != entry->dest
5200 && region[i] == loop->header)
5204 set_loop_copy (loop, loop);
5206 /* In case the function is used for loop header copying (which is the primary
5207 use), ensure that EXIT and its copy will be new latch and entry edges. */
5208 if (loop->header == entry->dest)
5210 copying_header = true;
5211 set_loop_copy (loop, loop_outer (loop));
5213 if (!dominated_by_p (CDI_DOMINATORS, loop->latch, exit->src))
5216 for (i = 0; i < n_region; i++)
5217 if (region[i] != exit->src
5218 && dominated_by_p (CDI_DOMINATORS, region[i], exit->src))
5224 region_copy = XNEWVEC (basic_block, n_region);
5225 free_region_copy = true;
5228 gcc_assert (!need_ssa_update_p (cfun));
5230 /* Record blocks outside the region that are dominated by something
5233 initialize_original_copy_tables ();
5235 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5237 if (entry->dest->count)
5239 total_count = entry->dest->count;
5240 entry_count = entry->count;
5241 /* Fix up corner cases, to avoid division by zero or creation of negative
5243 if (entry_count > total_count)
5244 entry_count = total_count;
5248 total_freq = entry->dest->frequency;
5249 entry_freq = EDGE_FREQUENCY (entry);
5250 /* Fix up corner cases, to avoid division by zero or creation of negative
5252 if (total_freq == 0)
5254 else if (entry_freq > total_freq)
5255 entry_freq = total_freq;
5258 copy_bbs (region, n_region, region_copy, &exit, 1, &exit_copy, loop,
5259 split_edge_bb_loc (entry));
5262 scale_bbs_frequencies_gcov_type (region, n_region,
5263 total_count - entry_count,
5265 scale_bbs_frequencies_gcov_type (region_copy, n_region, entry_count,
5270 scale_bbs_frequencies_int (region, n_region, total_freq - entry_freq,
5272 scale_bbs_frequencies_int (region_copy, n_region, entry_freq, total_freq);
5277 loop->header = exit->dest;
5278 loop->latch = exit->src;
5281 /* Redirect the entry and add the phi node arguments. */
5282 redirected = redirect_edge_and_branch (entry, get_bb_copy (entry->dest));
5283 gcc_assert (redirected != NULL);
5284 flush_pending_stmts (entry);
5286 /* Concerning updating of dominators: We must recount dominators
5287 for entry block and its copy. Anything that is outside of the
5288 region, but was dominated by something inside needs recounting as
5290 set_immediate_dominator (CDI_DOMINATORS, entry->dest, entry->src);
5291 VEC_safe_push (basic_block, heap, doms, get_bb_original (entry->dest));
5292 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5293 VEC_free (basic_block, heap, doms);
5295 /* Add the other PHI node arguments. */
5296 add_phi_args_after_copy (region_copy, n_region, NULL);
5298 /* Update the SSA web. */
5299 update_ssa (TODO_update_ssa);
5301 if (free_region_copy)
5304 free_original_copy_tables ();
5308 /* Duplicates REGION consisting of N_REGION blocks. The new blocks
5309 are stored to REGION_COPY in the same order in that they appear
5310 in REGION, if REGION_COPY is not NULL. ENTRY is the entry to
5311 the region, EXIT an exit from it. The condition guarding EXIT
5312 is moved to ENTRY. Returns true if duplication succeeds, false
5338 gimple_duplicate_sese_tail (edge entry ATTRIBUTE_UNUSED, edge exit ATTRIBUTE_UNUSED,
5339 basic_block *region ATTRIBUTE_UNUSED, unsigned n_region ATTRIBUTE_UNUSED,
5340 basic_block *region_copy ATTRIBUTE_UNUSED)
5343 bool free_region_copy = false;
5344 struct loop *loop = exit->dest->loop_father;
5345 struct loop *orig_loop = entry->dest->loop_father;
5346 basic_block switch_bb, entry_bb, nentry_bb;
5347 VEC (basic_block, heap) *doms;
5348 int total_freq = 0, exit_freq = 0;
5349 gcov_type total_count = 0, exit_count = 0;
5350 edge exits[2], nexits[2], e;
5351 gimple_stmt_iterator gsi;
5355 gcc_assert (EDGE_COUNT (exit->src->succs) == 2);
5357 exits[1] = EDGE_SUCC (exit->src, EDGE_SUCC (exit->src, 0) == exit);
5359 if (!can_copy_bbs_p (region, n_region))
5362 /* Some sanity checking. Note that we do not check for all possible
5363 missuses of the functions. I.e. if you ask to copy something weird
5364 (e.g., in the example, if there is a jump from inside to the middle
5365 of some_code, or come_code defines some of the values used in cond)
5366 it will work, but the resulting code will not be correct. */
5367 for (i = 0; i < n_region; i++)
5369 /* We do not handle subloops, i.e. all the blocks must belong to the
5371 if (region[i]->loop_father != orig_loop)
5374 if (region[i] == orig_loop->latch)
5378 initialize_original_copy_tables ();
5379 set_loop_copy (orig_loop, loop);
5383 region_copy = XNEWVEC (basic_block, n_region);
5384 free_region_copy = true;
5387 gcc_assert (!need_ssa_update_p (cfun));
5389 /* Record blocks outside the region that are dominated by something
5391 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5393 if (exit->src->count)
5395 total_count = exit->src->count;
5396 exit_count = exit->count;
5397 /* Fix up corner cases, to avoid division by zero or creation of negative
5399 if (exit_count > total_count)
5400 exit_count = total_count;
5404 total_freq = exit->src->frequency;
5405 exit_freq = EDGE_FREQUENCY (exit);
5406 /* Fix up corner cases, to avoid division by zero or creation of negative
5408 if (total_freq == 0)
5410 if (exit_freq > total_freq)
5411 exit_freq = total_freq;
5414 copy_bbs (region, n_region, region_copy, exits, 2, nexits, orig_loop,
5415 split_edge_bb_loc (exit));
5418 scale_bbs_frequencies_gcov_type (region, n_region,
5419 total_count - exit_count,
5421 scale_bbs_frequencies_gcov_type (region_copy, n_region, exit_count,
5426 scale_bbs_frequencies_int (region, n_region, total_freq - exit_freq,
5428 scale_bbs_frequencies_int (region_copy, n_region, exit_freq, total_freq);
5431 /* Create the switch block, and put the exit condition to it. */
5432 entry_bb = entry->dest;
5433 nentry_bb = get_bb_copy (entry_bb);
5434 if (!last_stmt (entry->src)
5435 || !stmt_ends_bb_p (last_stmt (entry->src)))
5436 switch_bb = entry->src;
5438 switch_bb = split_edge (entry);
5439 set_immediate_dominator (CDI_DOMINATORS, nentry_bb, switch_bb);
5441 gsi = gsi_last_bb (switch_bb);
5442 cond_stmt = last_stmt (exit->src);
5443 gcc_assert (gimple_code (cond_stmt) == GIMPLE_COND);
5444 cond_stmt = gimple_copy (cond_stmt);
5445 gimple_cond_set_lhs (cond_stmt, unshare_expr (gimple_cond_lhs (cond_stmt)));
5446 gimple_cond_set_rhs (cond_stmt, unshare_expr (gimple_cond_rhs (cond_stmt)));
5447 gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT);
5449 sorig = single_succ_edge (switch_bb);
5450 sorig->flags = exits[1]->flags;
5451 snew = make_edge (switch_bb, nentry_bb, exits[0]->flags);
5453 /* Register the new edge from SWITCH_BB in loop exit lists. */
5454 rescan_loop_exit (snew, true, false);
5456 /* Add the PHI node arguments. */
5457 add_phi_args_after_copy (region_copy, n_region, snew);
5459 /* Get rid of now superfluous conditions and associated edges (and phi node
5461 e = redirect_edge_and_branch (exits[0], exits[1]->dest);
5462 PENDING_STMT (e) = NULL;
5463 e = redirect_edge_and_branch (nexits[1], nexits[0]->dest);
5464 PENDING_STMT (e) = NULL;
5466 /* Anything that is outside of the region, but was dominated by something
5467 inside needs to update dominance info. */
5468 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5469 VEC_free (basic_block, heap, doms);
5471 /* Update the SSA web. */
5472 update_ssa (TODO_update_ssa);
5474 if (free_region_copy)
5477 free_original_copy_tables ();
5481 /* Add all the blocks dominated by ENTRY to the array BBS_P. Stop
5482 adding blocks when the dominator traversal reaches EXIT. This
5483 function silently assumes that ENTRY strictly dominates EXIT. */
5486 gather_blocks_in_sese_region (basic_block entry, basic_block exit,
5487 VEC(basic_block,heap) **bbs_p)
5491 for (son = first_dom_son (CDI_DOMINATORS, entry);
5493 son = next_dom_son (CDI_DOMINATORS, son))
5495 VEC_safe_push (basic_block, heap, *bbs_p, son);
5497 gather_blocks_in_sese_region (son, exit, bbs_p);
5501 /* Replaces *TP with a duplicate (belonging to function TO_CONTEXT).
5502 The duplicates are recorded in VARS_MAP. */
5505 replace_by_duplicate_decl (tree *tp, struct pointer_map_t *vars_map,
5508 tree t = *tp, new_t;
5509 struct function *f = DECL_STRUCT_FUNCTION (to_context);
5512 if (DECL_CONTEXT (t) == to_context)
5515 loc = pointer_map_contains (vars_map, t);
5519 loc = pointer_map_insert (vars_map, t);
5523 new_t = copy_var_decl (t, DECL_NAME (t), TREE_TYPE (t));
5524 f->local_decls = tree_cons (NULL_TREE, new_t, f->local_decls);
5528 gcc_assert (TREE_CODE (t) == CONST_DECL);
5529 new_t = copy_node (t);
5531 DECL_CONTEXT (new_t) = to_context;
5536 new_t = (tree) *loc;
5542 /* Creates an ssa name in TO_CONTEXT equivalent to NAME.
5543 VARS_MAP maps old ssa names and var_decls to the new ones. */
5546 replace_ssa_name (tree name, struct pointer_map_t *vars_map,
5550 tree new_name, decl = SSA_NAME_VAR (name);
5552 gcc_assert (is_gimple_reg (name));
5554 loc = pointer_map_contains (vars_map, name);
5558 replace_by_duplicate_decl (&decl, vars_map, to_context);
5560 push_cfun (DECL_STRUCT_FUNCTION (to_context));
5561 if (gimple_in_ssa_p (cfun))
5562 add_referenced_var (decl);
5564 new_name = make_ssa_name (decl, SSA_NAME_DEF_STMT (name));
5565 if (SSA_NAME_IS_DEFAULT_DEF (name))
5566 set_default_def (decl, new_name);
5569 loc = pointer_map_insert (vars_map, name);
5573 new_name = (tree) *loc;
5584 struct pointer_map_t *vars_map;
5585 htab_t new_label_map;
5589 /* Helper for move_block_to_fn. Set TREE_BLOCK in every expression
5590 contained in *TP if it has been ORIG_BLOCK previously and change the
5591 DECL_CONTEXT of every local variable referenced in *TP. */
5594 move_stmt_op (tree *tp, int *walk_subtrees, void *data)
5596 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
5597 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5601 /* We should never have TREE_BLOCK set on non-statements. */
5602 gcc_assert (!TREE_BLOCK (t));
5604 else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
5606 if (TREE_CODE (t) == SSA_NAME)
5607 *tp = replace_ssa_name (t, p->vars_map, p->to_context);
5608 else if (TREE_CODE (t) == LABEL_DECL)
5610 if (p->new_label_map)
5612 struct tree_map in, *out;
5614 out = (struct tree_map *)
5615 htab_find_with_hash (p->new_label_map, &in, DECL_UID (t));
5620 DECL_CONTEXT (t) = p->to_context;
5622 else if (p->remap_decls_p)
5624 /* Replace T with its duplicate. T should no longer appear in the
5625 parent function, so this looks wasteful; however, it may appear
5626 in referenced_vars, and more importantly, as virtual operands of
5627 statements, and in alias lists of other variables. It would be
5628 quite difficult to expunge it from all those places. ??? It might
5629 suffice to do this for addressable variables. */
5630 if ((TREE_CODE (t) == VAR_DECL
5631 && !is_global_var (t))
5632 || TREE_CODE (t) == CONST_DECL)
5633 replace_by_duplicate_decl (tp, p->vars_map, p->to_context);
5636 && gimple_in_ssa_p (cfun))
5638 push_cfun (DECL_STRUCT_FUNCTION (p->to_context));
5639 add_referenced_var (*tp);
5645 else if (TYPE_P (t))
5651 /* Like move_stmt_op, but for gimple statements.
5653 Helper for move_block_to_fn. Set GIMPLE_BLOCK in every expression
5654 contained in the current statement in *GSI_P and change the
5655 DECL_CONTEXT of every local variable referenced in the current
5659 move_stmt_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
5660 struct walk_stmt_info *wi)
5662 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5663 gimple stmt = gsi_stmt (*gsi_p);
5664 tree block = gimple_block (stmt);
5666 if (p->orig_block == NULL_TREE
5667 || block == p->orig_block
5668 || block == NULL_TREE)
5669 gimple_set_block (stmt, p->new_block);
5670 #ifdef ENABLE_CHECKING
5671 else if (block != p->new_block)
5673 while (block && block != p->orig_block)
5674 block = BLOCK_SUPERCONTEXT (block);
5679 if (is_gimple_omp (stmt)
5680 && gimple_code (stmt) != GIMPLE_OMP_RETURN
5681 && gimple_code (stmt) != GIMPLE_OMP_CONTINUE)
5683 /* Do not remap variables inside OMP directives. Variables
5684 referenced in clauses and directive header belong to the
5685 parent function and should not be moved into the child
5687 bool save_remap_decls_p = p->remap_decls_p;
5688 p->remap_decls_p = false;
5689 *handled_ops_p = true;
5691 walk_gimple_seq (gimple_omp_body (stmt), move_stmt_r, move_stmt_op, wi);
5693 p->remap_decls_p = save_remap_decls_p;
5699 /* Marks virtual operands of all statements in basic blocks BBS for
5703 mark_virtual_ops_in_bb (basic_block bb)
5705 gimple_stmt_iterator gsi;
5707 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5708 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5710 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5711 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5714 /* Move basic block BB from function CFUN to function DEST_FN. The
5715 block is moved out of the original linked list and placed after
5716 block AFTER in the new list. Also, the block is removed from the
5717 original array of blocks and placed in DEST_FN's array of blocks.
5718 If UPDATE_EDGE_COUNT_P is true, the edge counts on both CFGs is
5719 updated to reflect the moved edges.
5721 The local variables are remapped to new instances, VARS_MAP is used
5722 to record the mapping. */
5725 move_block_to_fn (struct function *dest_cfun, basic_block bb,
5726 basic_block after, bool update_edge_count_p,
5727 struct move_stmt_d *d, int eh_offset)
5729 struct control_flow_graph *cfg;
5732 gimple_stmt_iterator si;
5733 unsigned old_len, new_len;
5735 /* Remove BB from dominance structures. */
5736 delete_from_dominance_info (CDI_DOMINATORS, bb);
5738 remove_bb_from_loops (bb);
5740 /* Link BB to the new linked list. */
5741 move_block_after (bb, after);
5743 /* Update the edge count in the corresponding flowgraphs. */
5744 if (update_edge_count_p)
5745 FOR_EACH_EDGE (e, ei, bb->succs)
5747 cfun->cfg->x_n_edges--;
5748 dest_cfun->cfg->x_n_edges++;
5751 /* Remove BB from the original basic block array. */
5752 VEC_replace (basic_block, cfun->cfg->x_basic_block_info, bb->index, NULL);
5753 cfun->cfg->x_n_basic_blocks--;
5755 /* Grow DEST_CFUN's basic block array if needed. */
5756 cfg = dest_cfun->cfg;
5757 cfg->x_n_basic_blocks++;
5758 if (bb->index >= cfg->x_last_basic_block)
5759 cfg->x_last_basic_block = bb->index + 1;
5761 old_len = VEC_length (basic_block, cfg->x_basic_block_info);
5762 if ((unsigned) cfg->x_last_basic_block >= old_len)
5764 new_len = cfg->x_last_basic_block + (cfg->x_last_basic_block + 3) / 4;
5765 VEC_safe_grow_cleared (basic_block, gc, cfg->x_basic_block_info,
5769 VEC_replace (basic_block, cfg->x_basic_block_info,
5772 /* Remap the variables in phi nodes. */
5773 for (si = gsi_start_phis (bb); !gsi_end_p (si); )
5775 gimple phi = gsi_stmt (si);
5777 tree op = PHI_RESULT (phi);
5780 if (!is_gimple_reg (op))
5782 /* Remove the phi nodes for virtual operands (alias analysis will be
5783 run for the new function, anyway). */
5784 remove_phi_node (&si, true);
5788 SET_PHI_RESULT (phi,
5789 replace_ssa_name (op, d->vars_map, dest_cfun->decl));
5790 FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
5792 op = USE_FROM_PTR (use);
5793 if (TREE_CODE (op) == SSA_NAME)
5794 SET_USE (use, replace_ssa_name (op, d->vars_map, dest_cfun->decl));
5800 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
5802 gimple stmt = gsi_stmt (si);
5804 struct walk_stmt_info wi;
5806 memset (&wi, 0, sizeof (wi));
5808 walk_gimple_stmt (&si, move_stmt_r, move_stmt_op, &wi);
5810 if (gimple_code (stmt) == GIMPLE_LABEL)
5812 tree label = gimple_label_label (stmt);
5813 int uid = LABEL_DECL_UID (label);
5815 gcc_assert (uid > -1);
5817 old_len = VEC_length (basic_block, cfg->x_label_to_block_map);
5818 if (old_len <= (unsigned) uid)
5820 new_len = 3 * uid / 2 + 1;
5821 VEC_safe_grow_cleared (basic_block, gc,
5822 cfg->x_label_to_block_map, new_len);
5825 VEC_replace (basic_block, cfg->x_label_to_block_map, uid, bb);
5826 VEC_replace (basic_block, cfun->cfg->x_label_to_block_map, uid, NULL);
5828 gcc_assert (DECL_CONTEXT (label) == dest_cfun->decl);
5830 if (uid >= dest_cfun->cfg->last_label_uid)
5831 dest_cfun->cfg->last_label_uid = uid + 1;
5833 else if (gimple_code (stmt) == GIMPLE_RESX && eh_offset != 0)
5834 gimple_resx_set_region (stmt, gimple_resx_region (stmt) + eh_offset);
5836 region = lookup_stmt_eh_region (stmt);
5839 add_stmt_to_eh_region_fn (dest_cfun, stmt, region + eh_offset);
5840 remove_stmt_from_eh_region (stmt);
5841 gimple_duplicate_stmt_histograms (dest_cfun, stmt, cfun, stmt);
5842 gimple_remove_stmt_histograms (cfun, stmt);
5845 /* We cannot leave any operands allocated from the operand caches of
5846 the current function. */
5847 free_stmt_operands (stmt);
5848 push_cfun (dest_cfun);
5853 FOR_EACH_EDGE (e, ei, bb->succs)
5856 tree block = e->goto_block;
5857 if (d->orig_block == NULL_TREE
5858 || block == d->orig_block)
5859 e->goto_block = d->new_block;
5860 #ifdef ENABLE_CHECKING
5861 else if (block != d->new_block)
5863 while (block && block != d->orig_block)
5864 block = BLOCK_SUPERCONTEXT (block);
5871 /* Examine the statements in BB (which is in SRC_CFUN); find and return
5872 the outermost EH region. Use REGION as the incoming base EH region. */
5875 find_outermost_region_in_block (struct function *src_cfun,
5876 basic_block bb, int region)
5878 gimple_stmt_iterator si;
5880 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
5882 gimple stmt = gsi_stmt (si);
5885 if (gimple_code (stmt) == GIMPLE_RESX)
5886 stmt_region = gimple_resx_region (stmt);
5888 stmt_region = lookup_stmt_eh_region_fn (src_cfun, stmt);
5889 if (stmt_region > 0)
5892 region = stmt_region;
5893 else if (stmt_region != region)
5895 region = eh_region_outermost (src_cfun, stmt_region, region);
5896 gcc_assert (region != -1);
5905 new_label_mapper (tree decl, void *data)
5907 htab_t hash = (htab_t) data;
5911 gcc_assert (TREE_CODE (decl) == LABEL_DECL);
5913 m = XNEW (struct tree_map);
5914 m->hash = DECL_UID (decl);
5915 m->base.from = decl;
5916 m->to = create_artificial_label ();
5917 LABEL_DECL_UID (m->to) = LABEL_DECL_UID (decl);
5918 if (LABEL_DECL_UID (m->to) >= cfun->cfg->last_label_uid)
5919 cfun->cfg->last_label_uid = LABEL_DECL_UID (m->to) + 1;
5921 slot = htab_find_slot_with_hash (hash, m, m->hash, INSERT);
5922 gcc_assert (*slot == NULL);
5929 /* Change DECL_CONTEXT of all BLOCK_VARS in block, including
5933 replace_block_vars_by_duplicates (tree block, struct pointer_map_t *vars_map,
5938 for (tp = &BLOCK_VARS (block); *tp; tp = &TREE_CHAIN (*tp))
5941 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != CONST_DECL)
5943 replace_by_duplicate_decl (&t, vars_map, to_context);
5946 if (TREE_CODE (*tp) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (*tp))
5948 SET_DECL_VALUE_EXPR (t, DECL_VALUE_EXPR (*tp));
5949 DECL_HAS_VALUE_EXPR_P (t) = 1;
5951 TREE_CHAIN (t) = TREE_CHAIN (*tp);
5956 for (block = BLOCK_SUBBLOCKS (block); block; block = BLOCK_CHAIN (block))
5957 replace_block_vars_by_duplicates (block, vars_map, to_context);
5960 /* Move a single-entry, single-exit region delimited by ENTRY_BB and
5961 EXIT_BB to function DEST_CFUN. The whole region is replaced by a
5962 single basic block in the original CFG and the new basic block is
5963 returned. DEST_CFUN must not have a CFG yet.
5965 Note that the region need not be a pure SESE region. Blocks inside
5966 the region may contain calls to abort/exit. The only restriction
5967 is that ENTRY_BB should be the only entry point and it must
5970 Change TREE_BLOCK of all statements in ORIG_BLOCK to the new
5971 functions outermost BLOCK, move all subblocks of ORIG_BLOCK
5972 to the new function.
5974 All local variables referenced in the region are assumed to be in
5975 the corresponding BLOCK_VARS and unexpanded variable lists
5976 associated with DEST_CFUN. */
5979 move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb,
5980 basic_block exit_bb, tree orig_block)
5982 VEC(basic_block,heap) *bbs, *dom_bbs;
5983 basic_block dom_entry = get_immediate_dominator (CDI_DOMINATORS, entry_bb);
5984 basic_block after, bb, *entry_pred, *exit_succ, abb;
5985 struct function *saved_cfun = cfun;
5986 int *entry_flag, *exit_flag, eh_offset;
5987 unsigned *entry_prob, *exit_prob;
5988 unsigned i, num_entry_edges, num_exit_edges;
5991 htab_t new_label_map;
5992 struct pointer_map_t *vars_map;
5993 struct loop *loop = entry_bb->loop_father;
5994 struct move_stmt_d d;
5996 /* If ENTRY does not strictly dominate EXIT, this cannot be an SESE
5998 gcc_assert (entry_bb != exit_bb
6000 || dominated_by_p (CDI_DOMINATORS, exit_bb, entry_bb)));
6002 /* Collect all the blocks in the region. Manually add ENTRY_BB
6003 because it won't be added by dfs_enumerate_from. */
6005 VEC_safe_push (basic_block, heap, bbs, entry_bb);
6006 gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs);
6008 /* The blocks that used to be dominated by something in BBS will now be
6009 dominated by the new block. */
6010 dom_bbs = get_dominated_by_region (CDI_DOMINATORS,
6011 VEC_address (basic_block, bbs),
6012 VEC_length (basic_block, bbs));
6014 /* Detach ENTRY_BB and EXIT_BB from CFUN->CFG. We need to remember
6015 the predecessor edges to ENTRY_BB and the successor edges to
6016 EXIT_BB so that we can re-attach them to the new basic block that
6017 will replace the region. */
6018 num_entry_edges = EDGE_COUNT (entry_bb->preds);
6019 entry_pred = (basic_block *) xcalloc (num_entry_edges, sizeof (basic_block));
6020 entry_flag = (int *) xcalloc (num_entry_edges, sizeof (int));
6021 entry_prob = XNEWVEC (unsigned, num_entry_edges);
6023 for (ei = ei_start (entry_bb->preds); (e = ei_safe_edge (ei)) != NULL;)
6025 entry_prob[i] = e->probability;
6026 entry_flag[i] = e->flags;
6027 entry_pred[i++] = e->src;
6033 num_exit_edges = EDGE_COUNT (exit_bb->succs);
6034 exit_succ = (basic_block *) xcalloc (num_exit_edges,
6035 sizeof (basic_block));
6036 exit_flag = (int *) xcalloc (num_exit_edges, sizeof (int));
6037 exit_prob = XNEWVEC (unsigned, num_exit_edges);
6039 for (ei = ei_start (exit_bb->succs); (e = ei_safe_edge (ei)) != NULL;)
6041 exit_prob[i] = e->probability;
6042 exit_flag[i] = e->flags;
6043 exit_succ[i++] = e->dest;
6055 /* Switch context to the child function to initialize DEST_FN's CFG. */
6056 gcc_assert (dest_cfun->cfg == NULL);
6057 push_cfun (dest_cfun);
6059 init_empty_tree_cfg ();
6061 /* Initialize EH information for the new function. */
6063 new_label_map = NULL;
6068 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6069 region = find_outermost_region_in_block (saved_cfun, bb, region);
6071 init_eh_for_function ();
6074 new_label_map = htab_create (17, tree_map_hash, tree_map_eq, free);
6075 eh_offset = duplicate_eh_regions (saved_cfun, new_label_mapper,
6076 new_label_map, region, 0);
6082 /* Move blocks from BBS into DEST_CFUN. */
6083 gcc_assert (VEC_length (basic_block, bbs) >= 2);
6084 after = dest_cfun->cfg->x_entry_block_ptr;
6085 vars_map = pointer_map_create ();
6087 memset (&d, 0, sizeof (d));
6088 d.vars_map = vars_map;
6089 d.from_context = cfun->decl;
6090 d.to_context = dest_cfun->decl;
6091 d.new_label_map = new_label_map;
6092 d.remap_decls_p = true;
6093 d.orig_block = orig_block;
6094 d.new_block = DECL_INITIAL (dest_cfun->decl);
6096 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6098 /* No need to update edge counts on the last block. It has
6099 already been updated earlier when we detached the region from
6100 the original CFG. */
6101 move_block_to_fn (dest_cfun, bb, after, bb != exit_bb, &d, eh_offset);
6105 /* Rewire BLOCK_SUBBLOCKS of orig_block. */
6109 gcc_assert (BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6111 BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6112 = BLOCK_SUBBLOCKS (orig_block);
6113 for (block = BLOCK_SUBBLOCKS (orig_block);
6114 block; block = BLOCK_CHAIN (block))
6115 BLOCK_SUPERCONTEXT (block) = DECL_INITIAL (dest_cfun->decl);
6116 BLOCK_SUBBLOCKS (orig_block) = NULL_TREE;
6119 replace_block_vars_by_duplicates (DECL_INITIAL (dest_cfun->decl),
6120 vars_map, dest_cfun->decl);
6123 htab_delete (new_label_map);
6124 pointer_map_destroy (vars_map);
6126 /* Rewire the entry and exit blocks. The successor to the entry
6127 block turns into the successor of DEST_FN's ENTRY_BLOCK_PTR in
6128 the child function. Similarly, the predecessor of DEST_FN's
6129 EXIT_BLOCK_PTR turns into the predecessor of EXIT_BLOCK_PTR. We
6130 need to switch CFUN between DEST_CFUN and SAVED_CFUN so that the
6131 various CFG manipulation function get to the right CFG.
6133 FIXME, this is silly. The CFG ought to become a parameter to
6135 push_cfun (dest_cfun);
6136 make_edge (ENTRY_BLOCK_PTR, entry_bb, EDGE_FALLTHRU);
6138 make_edge (exit_bb, EXIT_BLOCK_PTR, 0);
6141 /* Back in the original function, the SESE region has disappeared,
6142 create a new basic block in its place. */
6143 bb = create_empty_bb (entry_pred[0]);
6145 add_bb_to_loop (bb, loop);
6146 for (i = 0; i < num_entry_edges; i++)
6148 e = make_edge (entry_pred[i], bb, entry_flag[i]);
6149 e->probability = entry_prob[i];
6152 for (i = 0; i < num_exit_edges; i++)
6154 e = make_edge (bb, exit_succ[i], exit_flag[i]);
6155 e->probability = exit_prob[i];
6158 set_immediate_dominator (CDI_DOMINATORS, bb, dom_entry);
6159 for (i = 0; VEC_iterate (basic_block, dom_bbs, i, abb); i++)
6160 set_immediate_dominator (CDI_DOMINATORS, abb, bb);
6161 VEC_free (basic_block, heap, dom_bbs);
6172 VEC_free (basic_block, heap, bbs);
6178 /* Dump FUNCTION_DECL FN to file FILE using FLAGS (see TDF_* in tree-pass.h)
6182 dump_function_to_file (tree fn, FILE *file, int flags)
6184 tree arg, vars, var;
6185 struct function *dsf;
6186 bool ignore_topmost_bind = false, any_var = false;
6190 fprintf (file, "%s (", lang_hooks.decl_printable_name (fn, 2));
6192 arg = DECL_ARGUMENTS (fn);
6195 print_generic_expr (file, TREE_TYPE (arg), dump_flags);
6196 fprintf (file, " ");
6197 print_generic_expr (file, arg, dump_flags);
6198 if (flags & TDF_VERBOSE)
6199 print_node (file, "", arg, 4);
6200 if (TREE_CHAIN (arg))
6201 fprintf (file, ", ");
6202 arg = TREE_CHAIN (arg);
6204 fprintf (file, ")\n");
6206 if (flags & TDF_VERBOSE)
6207 print_node (file, "", fn, 2);
6209 dsf = DECL_STRUCT_FUNCTION (fn);
6210 if (dsf && (flags & TDF_DETAILS))
6211 dump_eh_tree (file, dsf);
6213 if (flags & TDF_RAW && !gimple_has_body_p (fn))
6215 dump_node (fn, TDF_SLIM | flags, file);
6219 /* Switch CFUN to point to FN. */
6220 push_cfun (DECL_STRUCT_FUNCTION (fn));
6222 /* When GIMPLE is lowered, the variables are no longer available in
6223 BIND_EXPRs, so display them separately. */
6224 if (cfun && cfun->decl == fn && cfun->local_decls)
6226 ignore_topmost_bind = true;
6228 fprintf (file, "{\n");
6229 for (vars = cfun->local_decls; vars; vars = TREE_CHAIN (vars))
6231 var = TREE_VALUE (vars);
6233 print_generic_decl (file, var, flags);
6234 if (flags & TDF_VERBOSE)
6235 print_node (file, "", var, 4);
6236 fprintf (file, "\n");
6242 if (cfun && cfun->decl == fn && cfun->cfg && basic_block_info)
6244 /* If the CFG has been built, emit a CFG-based dump. */
6245 check_bb_profile (ENTRY_BLOCK_PTR, file);
6246 if (!ignore_topmost_bind)
6247 fprintf (file, "{\n");
6249 if (any_var && n_basic_blocks)
6250 fprintf (file, "\n");
6253 gimple_dump_bb (bb, file, 2, flags);
6255 fprintf (file, "}\n");
6256 check_bb_profile (EXIT_BLOCK_PTR, file);
6258 else if (DECL_SAVED_TREE (fn) == NULL)
6260 /* The function is now in GIMPLE form but the CFG has not been
6261 built yet. Emit the single sequence of GIMPLE statements
6262 that make up its body. */
6263 gimple_seq body = gimple_body (fn);
6265 if (gimple_seq_first_stmt (body)
6266 && gimple_seq_first_stmt (body) == gimple_seq_last_stmt (body)
6267 && gimple_code (gimple_seq_first_stmt (body)) == GIMPLE_BIND)
6268 print_gimple_seq (file, body, 0, flags);
6271 if (!ignore_topmost_bind)
6272 fprintf (file, "{\n");
6275 fprintf (file, "\n");
6277 print_gimple_seq (file, body, 2, flags);
6278 fprintf (file, "}\n");
6285 /* Make a tree based dump. */
6286 chain = DECL_SAVED_TREE (fn);
6288 if (chain && TREE_CODE (chain) == BIND_EXPR)
6290 if (ignore_topmost_bind)
6292 chain = BIND_EXPR_BODY (chain);
6300 if (!ignore_topmost_bind)
6301 fprintf (file, "{\n");
6306 fprintf (file, "\n");
6308 print_generic_stmt_indented (file, chain, flags, indent);
6309 if (ignore_topmost_bind)
6310 fprintf (file, "}\n");
6313 fprintf (file, "\n\n");
6320 /* Dump FUNCTION_DECL FN to stderr using FLAGS (see TDF_* in tree.h) */
6323 debug_function (tree fn, int flags)
6325 dump_function_to_file (fn, stderr, flags);
6329 /* Print on FILE the indexes for the predecessors of basic_block BB. */
6332 print_pred_bbs (FILE *file, basic_block bb)
6337 FOR_EACH_EDGE (e, ei, bb->preds)
6338 fprintf (file, "bb_%d ", e->src->index);
6342 /* Print on FILE the indexes for the successors of basic_block BB. */
6345 print_succ_bbs (FILE *file, basic_block bb)
6350 FOR_EACH_EDGE (e, ei, bb->succs)
6351 fprintf (file, "bb_%d ", e->dest->index);
6354 /* Print to FILE the basic block BB following the VERBOSITY level. */
6357 print_loops_bb (FILE *file, basic_block bb, int indent, int verbosity)
6359 char *s_indent = (char *) alloca ((size_t) indent + 1);
6360 memset ((void *) s_indent, ' ', (size_t) indent);
6361 s_indent[indent] = '\0';
6363 /* Print basic_block's header. */
6366 fprintf (file, "%s bb_%d (preds = {", s_indent, bb->index);
6367 print_pred_bbs (file, bb);
6368 fprintf (file, "}, succs = {");
6369 print_succ_bbs (file, bb);
6370 fprintf (file, "})\n");
6373 /* Print basic_block's body. */
6376 fprintf (file, "%s {\n", s_indent);
6377 gimple_dump_bb (bb, file, indent + 4, TDF_VOPS|TDF_MEMSYMS);
6378 fprintf (file, "%s }\n", s_indent);
6382 static void print_loop_and_siblings (FILE *, struct loop *, int, int);
6384 /* Pretty print LOOP on FILE, indented INDENT spaces. Following
6385 VERBOSITY level this outputs the contents of the loop, or just its
6389 print_loop (FILE *file, struct loop *loop, int indent, int verbosity)
6397 s_indent = (char *) alloca ((size_t) indent + 1);
6398 memset ((void *) s_indent, ' ', (size_t) indent);
6399 s_indent[indent] = '\0';
6401 /* Print loop's header. */
6402 fprintf (file, "%sloop_%d (header = %d, latch = %d", s_indent,
6403 loop->num, loop->header->index, loop->latch->index);
6404 fprintf (file, ", niter = ");
6405 print_generic_expr (file, loop->nb_iterations, 0);
6407 if (loop->any_upper_bound)
6409 fprintf (file, ", upper_bound = ");
6410 dump_double_int (file, loop->nb_iterations_upper_bound, true);
6413 if (loop->any_estimate)
6415 fprintf (file, ", estimate = ");
6416 dump_double_int (file, loop->nb_iterations_estimate, true);
6418 fprintf (file, ")\n");
6420 /* Print loop's body. */
6423 fprintf (file, "%s{\n", s_indent);
6425 if (bb->loop_father == loop)
6426 print_loops_bb (file, bb, indent, verbosity);
6428 print_loop_and_siblings (file, loop->inner, indent + 2, verbosity);
6429 fprintf (file, "%s}\n", s_indent);
6433 /* Print the LOOP and its sibling loops on FILE, indented INDENT
6434 spaces. Following VERBOSITY level this outputs the contents of the
6435 loop, or just its structure. */
6438 print_loop_and_siblings (FILE *file, struct loop *loop, int indent, int verbosity)
6443 print_loop (file, loop, indent, verbosity);
6444 print_loop_and_siblings (file, loop->next, indent, verbosity);
6447 /* Follow a CFG edge from the entry point of the program, and on entry
6448 of a loop, pretty print the loop structure on FILE. */
6451 print_loops (FILE *file, int verbosity)
6455 bb = ENTRY_BLOCK_PTR;
6456 if (bb && bb->loop_father)
6457 print_loop_and_siblings (file, bb->loop_father, 0, verbosity);
6461 /* Debugging loops structure at tree level, at some VERBOSITY level. */
6464 debug_loops (int verbosity)
6466 print_loops (stderr, verbosity);
6469 /* Print on stderr the code of LOOP, at some VERBOSITY level. */
6472 debug_loop (struct loop *loop, int verbosity)
6474 print_loop (stderr, loop, 0, verbosity);
6477 /* Print on stderr the code of loop number NUM, at some VERBOSITY
6481 debug_loop_num (unsigned num, int verbosity)
6483 debug_loop (get_loop (num), verbosity);
6486 /* Return true if BB ends with a call, possibly followed by some
6487 instructions that must stay with the call. Return false,
6491 gimple_block_ends_with_call_p (basic_block bb)
6493 gimple_stmt_iterator gsi = gsi_last_bb (bb);
6494 return is_gimple_call (gsi_stmt (gsi));
6498 /* Return true if BB ends with a conditional branch. Return false,
6502 gimple_block_ends_with_condjump_p (const_basic_block bb)
6504 gimple stmt = last_stmt (CONST_CAST_BB (bb));
6505 return (stmt && gimple_code (stmt) == GIMPLE_COND);
6509 /* Return true if we need to add fake edge to exit at statement T.
6510 Helper function for gimple_flow_call_edges_add. */
6513 need_fake_edge_p (gimple t)
6515 tree fndecl = NULL_TREE;
6518 /* NORETURN and LONGJMP calls already have an edge to exit.
6519 CONST and PURE calls do not need one.
6520 We don't currently check for CONST and PURE here, although
6521 it would be a good idea, because those attributes are
6522 figured out from the RTL in mark_constant_function, and
6523 the counter incrementation code from -fprofile-arcs
6524 leads to different results from -fbranch-probabilities. */
6525 if (is_gimple_call (t))
6527 fndecl = gimple_call_fndecl (t);
6528 call_flags = gimple_call_flags (t);
6531 if (is_gimple_call (t)
6533 && DECL_BUILT_IN (fndecl)
6534 && (call_flags & ECF_NOTHROW)
6535 && !(call_flags & ECF_RETURNS_TWICE)
6536 /* fork() doesn't really return twice, but the effect of
6537 wrapping it in __gcov_fork() which calls __gcov_flush()
6538 and clears the counters before forking has the same
6539 effect as returning twice. Force a fake edge. */
6540 && !(DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6541 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_FORK))
6544 if (is_gimple_call (t)
6545 && !(call_flags & ECF_NORETURN))
6548 if (gimple_code (t) == GIMPLE_ASM
6549 && (gimple_asm_volatile_p (t) || gimple_asm_input_p (t)))
6556 /* Add fake edges to the function exit for any non constant and non
6557 noreturn calls, volatile inline assembly in the bitmap of blocks
6558 specified by BLOCKS or to the whole CFG if BLOCKS is zero. Return
6559 the number of blocks that were split.
6561 The goal is to expose cases in which entering a basic block does
6562 not imply that all subsequent instructions must be executed. */
6565 gimple_flow_call_edges_add (sbitmap blocks)
6568 int blocks_split = 0;
6569 int last_bb = last_basic_block;
6570 bool check_last_block = false;
6572 if (n_basic_blocks == NUM_FIXED_BLOCKS)
6576 check_last_block = true;
6578 check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index);
6580 /* In the last basic block, before epilogue generation, there will be
6581 a fallthru edge to EXIT. Special care is required if the last insn
6582 of the last basic block is a call because make_edge folds duplicate
6583 edges, which would result in the fallthru edge also being marked
6584 fake, which would result in the fallthru edge being removed by
6585 remove_fake_edges, which would result in an invalid CFG.
6587 Moreover, we can't elide the outgoing fake edge, since the block
6588 profiler needs to take this into account in order to solve the minimal
6589 spanning tree in the case that the call doesn't return.
6591 Handle this by adding a dummy instruction in a new last basic block. */
6592 if (check_last_block)
6594 basic_block bb = EXIT_BLOCK_PTR->prev_bb;
6595 gimple_stmt_iterator gsi = gsi_last_bb (bb);
6598 if (!gsi_end_p (gsi))
6601 if (t && need_fake_edge_p (t))
6605 e = find_edge (bb, EXIT_BLOCK_PTR);
6608 gsi_insert_on_edge (e, gimple_build_nop ());
6609 gsi_commit_edge_inserts ();
6614 /* Now add fake edges to the function exit for any non constant
6615 calls since there is no way that we can determine if they will
6617 for (i = 0; i < last_bb; i++)
6619 basic_block bb = BASIC_BLOCK (i);
6620 gimple_stmt_iterator gsi;
6621 gimple stmt, last_stmt;
6626 if (blocks && !TEST_BIT (blocks, i))
6629 gsi = gsi_last_bb (bb);
6630 if (!gsi_end_p (gsi))
6632 last_stmt = gsi_stmt (gsi);
6635 stmt = gsi_stmt (gsi);
6636 if (need_fake_edge_p (stmt))
6640 /* The handling above of the final block before the
6641 epilogue should be enough to verify that there is
6642 no edge to the exit block in CFG already.
6643 Calling make_edge in such case would cause us to
6644 mark that edge as fake and remove it later. */
6645 #ifdef ENABLE_CHECKING
6646 if (stmt == last_stmt)
6648 e = find_edge (bb, EXIT_BLOCK_PTR);
6649 gcc_assert (e == NULL);
6653 /* Note that the following may create a new basic block
6654 and renumber the existing basic blocks. */
6655 if (stmt != last_stmt)
6657 e = split_block (bb, stmt);
6661 make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE);
6665 while (!gsi_end_p (gsi));
6670 verify_flow_info ();
6672 return blocks_split;
6675 /* Purge dead abnormal call edges from basic block BB. */
6678 gimple_purge_dead_abnormal_call_edges (basic_block bb)
6680 bool changed = gimple_purge_dead_eh_edges (bb);
6682 if (cfun->has_nonlocal_label)
6684 gimple stmt = last_stmt (bb);
6688 if (!(stmt && stmt_can_make_abnormal_goto (stmt)))
6689 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6691 if (e->flags & EDGE_ABNORMAL)
6700 /* See gimple_purge_dead_eh_edges below. */
6702 free_dominance_info (CDI_DOMINATORS);
6708 /* Removes edge E and all the blocks dominated by it, and updates dominance
6709 information. The IL in E->src needs to be updated separately.
6710 If dominance info is not available, only the edge E is removed.*/
6713 remove_edge_and_dominated_blocks (edge e)
6715 VEC (basic_block, heap) *bbs_to_remove = NULL;
6716 VEC (basic_block, heap) *bbs_to_fix_dom = NULL;
6720 bool none_removed = false;
6722 basic_block bb, dbb;
6725 if (!dom_info_available_p (CDI_DOMINATORS))
6731 /* No updating is needed for edges to exit. */
6732 if (e->dest == EXIT_BLOCK_PTR)
6734 if (cfgcleanup_altered_bbs)
6735 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6740 /* First, we find the basic blocks to remove. If E->dest has a predecessor
6741 that is not dominated by E->dest, then this set is empty. Otherwise,
6742 all the basic blocks dominated by E->dest are removed.
6744 Also, to DF_IDOM we store the immediate dominators of the blocks in
6745 the dominance frontier of E (i.e., of the successors of the
6746 removed blocks, if there are any, and of E->dest otherwise). */
6747 FOR_EACH_EDGE (f, ei, e->dest->preds)
6752 if (!dominated_by_p (CDI_DOMINATORS, f->src, e->dest))
6754 none_removed = true;
6759 df = BITMAP_ALLOC (NULL);
6760 df_idom = BITMAP_ALLOC (NULL);
6763 bitmap_set_bit (df_idom,
6764 get_immediate_dominator (CDI_DOMINATORS, e->dest)->index);
6767 bbs_to_remove = get_all_dominated_blocks (CDI_DOMINATORS, e->dest);
6768 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6770 FOR_EACH_EDGE (f, ei, bb->succs)
6772 if (f->dest != EXIT_BLOCK_PTR)
6773 bitmap_set_bit (df, f->dest->index);
6776 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6777 bitmap_clear_bit (df, bb->index);
6779 EXECUTE_IF_SET_IN_BITMAP (df, 0, i, bi)
6781 bb = BASIC_BLOCK (i);
6782 bitmap_set_bit (df_idom,
6783 get_immediate_dominator (CDI_DOMINATORS, bb)->index);
6787 if (cfgcleanup_altered_bbs)
6789 /* Record the set of the altered basic blocks. */
6790 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6791 bitmap_ior_into (cfgcleanup_altered_bbs, df);
6794 /* Remove E and the cancelled blocks. */
6799 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6800 delete_basic_block (bb);
6803 /* Update the dominance information. The immediate dominator may change only
6804 for blocks whose immediate dominator belongs to DF_IDOM:
6806 Suppose that idom(X) = Y before removal of E and idom(X) != Y after the
6807 removal. Let Z the arbitrary block such that idom(Z) = Y and
6808 Z dominates X after the removal. Before removal, there exists a path P
6809 from Y to X that avoids Z. Let F be the last edge on P that is
6810 removed, and let W = F->dest. Before removal, idom(W) = Y (since Y
6811 dominates W, and because of P, Z does not dominate W), and W belongs to
6812 the dominance frontier of E. Therefore, Y belongs to DF_IDOM. */
6813 EXECUTE_IF_SET_IN_BITMAP (df_idom, 0, i, bi)
6815 bb = BASIC_BLOCK (i);
6816 for (dbb = first_dom_son (CDI_DOMINATORS, bb);
6818 dbb = next_dom_son (CDI_DOMINATORS, dbb))
6819 VEC_safe_push (basic_block, heap, bbs_to_fix_dom, dbb);
6822 iterate_fix_dominators (CDI_DOMINATORS, bbs_to_fix_dom, true);
6825 BITMAP_FREE (df_idom);
6826 VEC_free (basic_block, heap, bbs_to_remove);
6827 VEC_free (basic_block, heap, bbs_to_fix_dom);
6830 /* Purge dead EH edges from basic block BB. */
6833 gimple_purge_dead_eh_edges (basic_block bb)
6835 bool changed = false;
6838 gimple stmt = last_stmt (bb);
6840 if (stmt && stmt_can_throw_internal (stmt))
6843 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6845 if (e->flags & EDGE_EH)
6847 remove_edge_and_dominated_blocks (e);
6858 gimple_purge_all_dead_eh_edges (const_bitmap blocks)
6860 bool changed = false;
6864 EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
6866 basic_block bb = BASIC_BLOCK (i);
6868 /* Earlier gimple_purge_dead_eh_edges could have removed
6869 this basic block already. */
6870 gcc_assert (bb || changed);
6872 changed |= gimple_purge_dead_eh_edges (bb);
6878 /* This function is called whenever a new edge is created or
6882 gimple_execute_on_growing_pred (edge e)
6884 basic_block bb = e->dest;
6887 reserve_phi_args_for_new_edge (bb);
6890 /* This function is called immediately before edge E is removed from
6891 the edge vector E->dest->preds. */
6894 gimple_execute_on_shrinking_pred (edge e)
6896 if (phi_nodes (e->dest))
6897 remove_phi_args (e);
6900 /*---------------------------------------------------------------------------
6901 Helper functions for Loop versioning
6902 ---------------------------------------------------------------------------*/
6904 /* Adjust phi nodes for 'first' basic block. 'second' basic block is a copy
6905 of 'first'. Both of them are dominated by 'new_head' basic block. When
6906 'new_head' was created by 'second's incoming edge it received phi arguments
6907 on the edge by split_edge(). Later, additional edge 'e' was created to
6908 connect 'new_head' and 'first'. Now this routine adds phi args on this
6909 additional edge 'e' that new_head to second edge received as part of edge
6913 gimple_lv_adjust_loop_header_phi (basic_block first, basic_block second,
6914 basic_block new_head, edge e)
6917 gimple_stmt_iterator psi1, psi2;
6919 edge e2 = find_edge (new_head, second);
6921 /* Because NEW_HEAD has been created by splitting SECOND's incoming
6922 edge, we should always have an edge from NEW_HEAD to SECOND. */
6923 gcc_assert (e2 != NULL);
6925 /* Browse all 'second' basic block phi nodes and add phi args to
6926 edge 'e' for 'first' head. PHI args are always in correct order. */
6928 for (psi2 = gsi_start_phis (second),
6929 psi1 = gsi_start_phis (first);
6930 !gsi_end_p (psi2) && !gsi_end_p (psi1);
6931 gsi_next (&psi2), gsi_next (&psi1))
6933 phi1 = gsi_stmt (psi1);
6934 phi2 = gsi_stmt (psi2);
6935 def = PHI_ARG_DEF (phi2, e2->dest_idx);
6936 add_phi_arg (phi1, def, e);
6941 /* Adds a if else statement to COND_BB with condition COND_EXPR.
6942 SECOND_HEAD is the destination of the THEN and FIRST_HEAD is
6943 the destination of the ELSE part. */
6946 gimple_lv_add_condition_to_bb (basic_block first_head ATTRIBUTE_UNUSED,
6947 basic_block second_head ATTRIBUTE_UNUSED,
6948 basic_block cond_bb, void *cond_e)
6950 gimple_stmt_iterator gsi;
6951 gimple new_cond_expr;
6952 tree cond_expr = (tree) cond_e;
6955 /* Build new conditional expr */
6956 new_cond_expr = gimple_build_cond_from_tree (cond_expr,
6957 NULL_TREE, NULL_TREE);
6959 /* Add new cond in cond_bb. */
6960 gsi = gsi_last_bb (cond_bb);
6961 gsi_insert_after (&gsi, new_cond_expr, GSI_NEW_STMT);
6963 /* Adjust edges appropriately to connect new head with first head
6964 as well as second head. */
6965 e0 = single_succ_edge (cond_bb);
6966 e0->flags &= ~EDGE_FALLTHRU;
6967 e0->flags |= EDGE_FALSE_VALUE;
6970 struct cfg_hooks gimple_cfg_hooks = {
6972 gimple_verify_flow_info,
6973 gimple_dump_bb, /* dump_bb */
6974 create_bb, /* create_basic_block */
6975 gimple_redirect_edge_and_branch, /* redirect_edge_and_branch */
6976 gimple_redirect_edge_and_branch_force, /* redirect_edge_and_branch_force */
6977 gimple_can_remove_branch_p, /* can_remove_branch_p */
6978 remove_bb, /* delete_basic_block */
6979 gimple_split_block, /* split_block */
6980 gimple_move_block_after, /* move_block_after */
6981 gimple_can_merge_blocks_p, /* can_merge_blocks_p */
6982 gimple_merge_blocks, /* merge_blocks */
6983 gimple_predict_edge, /* predict_edge */
6984 gimple_predicted_by_p, /* predicted_by_p */
6985 gimple_can_duplicate_bb_p, /* can_duplicate_block_p */
6986 gimple_duplicate_bb, /* duplicate_block */
6987 gimple_split_edge, /* split_edge */
6988 gimple_make_forwarder_block, /* make_forward_block */
6989 NULL, /* tidy_fallthru_edge */
6990 gimple_block_ends_with_call_p,/* block_ends_with_call_p */
6991 gimple_block_ends_with_condjump_p, /* block_ends_with_condjump_p */
6992 gimple_flow_call_edges_add, /* flow_call_edges_add */
6993 gimple_execute_on_growing_pred, /* execute_on_growing_pred */
6994 gimple_execute_on_shrinking_pred, /* execute_on_shrinking_pred */
6995 gimple_duplicate_loop_to_header_edge, /* duplicate loop for trees */
6996 gimple_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
6997 gimple_lv_adjust_loop_header_phi, /* lv_adjust_loop_header_phi*/
6998 extract_true_false_edges_from_block, /* extract_cond_bb_edges */
6999 flush_pending_stmts /* flush_pending_stmts */
7003 /* Split all critical edges. */
7006 split_critical_edges (void)
7012 /* split_edge can redirect edges out of SWITCH_EXPRs, which can get
7013 expensive. So we want to enable recording of edge to CASE_LABEL_EXPR
7014 mappings around the calls to split_edge. */
7015 start_recording_case_labels ();
7018 FOR_EACH_EDGE (e, ei, bb->succs)
7020 if (EDGE_CRITICAL_P (e) && !(e->flags & EDGE_ABNORMAL))
7022 /* PRE inserts statements to edges and expects that
7023 since split_critical_edges was done beforehand, committing edge
7024 insertions will not split more edges. In addition to critical
7025 edges we must split edges that have multiple successors and
7026 end by control flow statements, such as RESX.
7027 Go ahead and split them too. This matches the logic in
7028 gimple_find_edge_insert_loc. */
7029 else if ((!single_pred_p (e->dest)
7030 || phi_nodes (e->dest)
7031 || e->dest == EXIT_BLOCK_PTR)
7032 && e->src != ENTRY_BLOCK_PTR
7033 && !(e->flags & EDGE_ABNORMAL))
7035 gimple_stmt_iterator gsi;
7037 gsi = gsi_last_bb (e->src);
7038 if (!gsi_end_p (gsi)
7039 && stmt_ends_bb_p (gsi_stmt (gsi))
7040 && gimple_code (gsi_stmt (gsi)) != GIMPLE_RETURN)
7045 end_recording_case_labels ();
7049 struct gimple_opt_pass pass_split_crit_edges =
7053 "crited", /* name */
7055 split_critical_edges, /* execute */
7058 0, /* static_pass_number */
7059 TV_TREE_SPLIT_EDGES, /* tv_id */
7060 PROP_cfg, /* properties required */
7061 PROP_no_crit_edges, /* properties_provided */
7062 0, /* properties_destroyed */
7063 0, /* todo_flags_start */
7064 TODO_dump_func /* todo_flags_finish */
7069 /* Build a ternary operation and gimplify it. Emit code before GSI.
7070 Return the gimple_val holding the result. */
7073 gimplify_build3 (gimple_stmt_iterator *gsi, enum tree_code code,
7074 tree type, tree a, tree b, tree c)
7078 ret = fold_build3 (code, type, a, b, c);
7081 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7085 /* Build a binary operation and gimplify it. Emit code before GSI.
7086 Return the gimple_val holding the result. */
7089 gimplify_build2 (gimple_stmt_iterator *gsi, enum tree_code code,
7090 tree type, tree a, tree b)
7094 ret = fold_build2 (code, type, a, b);
7097 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7101 /* Build a unary operation and gimplify it. Emit code before GSI.
7102 Return the gimple_val holding the result. */
7105 gimplify_build1 (gimple_stmt_iterator *gsi, enum tree_code code, tree type,
7110 ret = fold_build1 (code, type, a);
7113 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7119 /* Emit return warnings. */
7122 execute_warn_function_return (void)
7124 source_location location;
7129 /* If we have a path to EXIT, then we do return. */
7130 if (TREE_THIS_VOLATILE (cfun->decl)
7131 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0)
7133 location = UNKNOWN_LOCATION;
7134 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7136 last = last_stmt (e->src);
7137 if (gimple_code (last) == GIMPLE_RETURN
7138 && (location = gimple_location (last)) != UNKNOWN_LOCATION)
7141 if (location == UNKNOWN_LOCATION)
7142 location = cfun->function_end_locus;
7143 warning (0, "%H%<noreturn%> function does return", &location);
7146 /* If we see "return;" in some basic block, then we do reach the end
7147 without returning a value. */
7148 else if (warn_return_type
7149 && !TREE_NO_WARNING (cfun->decl)
7150 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0
7151 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (cfun->decl))))
7153 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7155 gimple last = last_stmt (e->src);
7156 if (gimple_code (last) == GIMPLE_RETURN
7157 && gimple_return_retval (last) == NULL
7158 && !gimple_no_warning_p (last))
7160 location = gimple_location (last);
7161 if (location == UNKNOWN_LOCATION)
7162 location = cfun->function_end_locus;
7163 warning_at (location, OPT_Wreturn_type, "control reaches end of non-void function");
7164 TREE_NO_WARNING (cfun->decl) = 1;
7173 /* Given a basic block B which ends with a conditional and has
7174 precisely two successors, determine which of the edges is taken if
7175 the conditional is true and which is taken if the conditional is
7176 false. Set TRUE_EDGE and FALSE_EDGE appropriately. */
7179 extract_true_false_edges_from_block (basic_block b,
7183 edge e = EDGE_SUCC (b, 0);
7185 if (e->flags & EDGE_TRUE_VALUE)
7188 *false_edge = EDGE_SUCC (b, 1);
7193 *true_edge = EDGE_SUCC (b, 1);
7197 struct gimple_opt_pass pass_warn_function_return =
7203 execute_warn_function_return, /* execute */
7206 0, /* static_pass_number */
7207 TV_NONE, /* tv_id */
7208 PROP_cfg, /* properties_required */
7209 0, /* properties_provided */
7210 0, /* properties_destroyed */
7211 0, /* todo_flags_start */
7212 0 /* todo_flags_finish */
7216 /* Emit noreturn warnings. */
7219 execute_warn_function_noreturn (void)
7221 if (warn_missing_noreturn
7222 && !TREE_THIS_VOLATILE (cfun->decl)
7223 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0
7224 && !lang_hooks.missing_noreturn_ok_p (cfun->decl))
7225 warning (OPT_Wmissing_noreturn, "%Jfunction might be possible candidate "
7226 "for attribute %<noreturn%>",
7231 struct gimple_opt_pass pass_warn_function_noreturn =
7237 execute_warn_function_noreturn, /* execute */
7240 0, /* static_pass_number */
7241 TV_NONE, /* tv_id */
7242 PROP_cfg, /* properties_required */
7243 0, /* properties_provided */
7244 0, /* properties_destroyed */
7245 0, /* todo_flags_start */
7246 0 /* todo_flags_finish */