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)
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. */
1577 fold_stmt_inplace (stmt);
1579 data->may_branch = true;
1581 /* Replace trivial conditionals with gotos. */
1582 if (gimple_cond_true_p (stmt))
1584 /* Goto THEN label. */
1585 tree then_label = gimple_cond_true_label (stmt);
1587 gsi_replace (gsi, gimple_build_goto (then_label), false);
1588 data->last_goto_gsi = *gsi;
1589 data->last_was_goto = true;
1590 data->repeat = true;
1592 else if (gimple_cond_false_p (stmt))
1594 /* Goto ELSE label. */
1595 tree else_label = gimple_cond_false_label (stmt);
1597 gsi_replace (gsi, gimple_build_goto (else_label), false);
1598 data->last_goto_gsi = *gsi;
1599 data->last_was_goto = true;
1600 data->repeat = true;
1604 tree then_label = gimple_cond_true_label (stmt);
1605 tree else_label = gimple_cond_false_label (stmt);
1607 if (then_label == else_label)
1609 /* Goto common destination. */
1610 gsi_replace (gsi, gimple_build_goto (then_label), false);
1611 data->last_goto_gsi = *gsi;
1612 data->last_was_goto = true;
1613 data->repeat = true;
1619 data->last_was_goto = false;
1622 /* Helper for remove_useless_stmts_1.
1623 Handle the try-finally case for GIMPLE_TRY statements. */
1626 remove_useless_stmts_tf (gimple_stmt_iterator *gsi, struct rus_data *data)
1628 bool save_may_branch, save_may_throw;
1629 bool this_may_branch, this_may_throw;
1631 gimple_seq eval_seq, cleanup_seq;
1632 gimple_stmt_iterator eval_gsi, cleanup_gsi;
1634 gimple stmt = gsi_stmt (*gsi);
1636 /* Collect may_branch and may_throw information for the body only. */
1637 save_may_branch = data->may_branch;
1638 save_may_throw = data->may_throw;
1639 data->may_branch = false;
1640 data->may_throw = false;
1641 data->last_was_goto = false;
1643 eval_seq = gimple_try_eval (stmt);
1644 eval_gsi = gsi_start (eval_seq);
1645 remove_useless_stmts_1 (&eval_gsi, data);
1647 this_may_branch = data->may_branch;
1648 this_may_throw = data->may_throw;
1649 data->may_branch |= save_may_branch;
1650 data->may_throw |= save_may_throw;
1651 data->last_was_goto = false;
1653 cleanup_seq = gimple_try_cleanup (stmt);
1654 cleanup_gsi = gsi_start (cleanup_seq);
1655 remove_useless_stmts_1 (&cleanup_gsi, data);
1657 /* If the body is empty, then we can emit the FINALLY block without
1658 the enclosing TRY_FINALLY_EXPR. */
1659 if (gimple_seq_empty_p (eval_seq))
1661 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1662 gsi_remove (gsi, false);
1663 data->repeat = true;
1666 /* If the handler is empty, then we can emit the TRY block without
1667 the enclosing TRY_FINALLY_EXPR. */
1668 else if (gimple_seq_empty_p (cleanup_seq))
1670 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1671 gsi_remove (gsi, false);
1672 data->repeat = true;
1675 /* If the body neither throws, nor branches, then we can safely
1676 string the TRY and FINALLY blocks together. */
1677 else if (!this_may_branch && !this_may_throw)
1679 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1680 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1681 gsi_remove (gsi, false);
1682 data->repeat = true;
1688 /* Helper for remove_useless_stmts_1.
1689 Handle the try-catch case for GIMPLE_TRY statements. */
1692 remove_useless_stmts_tc (gimple_stmt_iterator *gsi, struct rus_data *data)
1694 bool save_may_throw, this_may_throw;
1696 gimple_seq eval_seq, cleanup_seq, handler_seq, failure_seq;
1697 gimple_stmt_iterator eval_gsi, cleanup_gsi, handler_gsi, failure_gsi;
1699 gimple stmt = gsi_stmt (*gsi);
1701 /* Collect may_throw information for the body only. */
1702 save_may_throw = data->may_throw;
1703 data->may_throw = false;
1704 data->last_was_goto = false;
1706 eval_seq = gimple_try_eval (stmt);
1707 eval_gsi = gsi_start (eval_seq);
1708 remove_useless_stmts_1 (&eval_gsi, data);
1710 this_may_throw = data->may_throw;
1711 data->may_throw = save_may_throw;
1713 cleanup_seq = gimple_try_cleanup (stmt);
1715 /* If the body cannot throw, then we can drop the entire TRY_CATCH_EXPR. */
1716 if (!this_may_throw)
1718 if (warn_notreached)
1720 remove_useless_stmts_warn_notreached (cleanup_seq);
1722 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1723 gsi_remove (gsi, false);
1724 data->repeat = true;
1728 /* Process the catch clause specially. We may be able to tell that
1729 no exceptions propagate past this point. */
1731 this_may_throw = true;
1732 cleanup_gsi = gsi_start (cleanup_seq);
1733 stmt = gsi_stmt (cleanup_gsi);
1734 data->last_was_goto = false;
1736 switch (gimple_code (stmt))
1739 /* If the first element is a catch, they all must be. */
1740 while (!gsi_end_p (cleanup_gsi))
1742 stmt = gsi_stmt (cleanup_gsi);
1743 /* If we catch all exceptions, then the body does not
1744 propagate exceptions past this point. */
1745 if (gimple_catch_types (stmt) == NULL)
1746 this_may_throw = false;
1747 data->last_was_goto = false;
1748 handler_seq = gimple_catch_handler (stmt);
1749 handler_gsi = gsi_start (handler_seq);
1750 remove_useless_stmts_1 (&handler_gsi, data);
1751 gsi_next (&cleanup_gsi);
1756 case GIMPLE_EH_FILTER:
1757 /* If the first element is an eh_filter, it should stand alone. */
1758 if (gimple_eh_filter_must_not_throw (stmt))
1759 this_may_throw = false;
1760 else if (gimple_eh_filter_types (stmt) == NULL)
1761 this_may_throw = false;
1762 failure_seq = gimple_eh_filter_failure (stmt);
1763 failure_gsi = gsi_start (failure_seq);
1764 remove_useless_stmts_1 (&failure_gsi, data);
1769 /* Otherwise this is a list of cleanup statements. */
1770 remove_useless_stmts_1 (&cleanup_gsi, data);
1772 /* If the cleanup is empty, then we can emit the TRY block without
1773 the enclosing TRY_CATCH_EXPR. */
1774 if (gimple_seq_empty_p (cleanup_seq))
1776 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1777 gsi_remove(gsi, false);
1778 data->repeat = true;
1785 data->may_throw |= this_may_throw;
1788 /* Helper for remove_useless_stmts_1. Handle GIMPLE_BIND statements. */
1791 remove_useless_stmts_bind (gimple_stmt_iterator *gsi, struct rus_data *data ATTRIBUTE_UNUSED)
1794 gimple_seq body_seq, fn_body_seq;
1795 gimple_stmt_iterator body_gsi;
1797 gimple stmt = gsi_stmt (*gsi);
1799 /* First remove anything underneath the BIND_EXPR. */
1801 body_seq = gimple_bind_body (stmt);
1802 body_gsi = gsi_start (body_seq);
1803 remove_useless_stmts_1 (&body_gsi, data);
1805 /* If the GIMPLE_BIND has no variables, then we can pull everything
1806 up one level and remove the GIMPLE_BIND, unless this is the toplevel
1807 GIMPLE_BIND for the current function or an inlined function.
1809 When this situation occurs we will want to apply this
1810 optimization again. */
1811 block = gimple_bind_block (stmt);
1812 fn_body_seq = gimple_body (current_function_decl);
1813 if (gimple_bind_vars (stmt) == NULL_TREE
1814 && (gimple_seq_empty_p (fn_body_seq)
1815 || stmt != gimple_seq_first_stmt (fn_body_seq))
1817 || ! BLOCK_ABSTRACT_ORIGIN (block)
1818 || (TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block))
1821 tree var = NULL_TREE;
1822 /* Even if there are no gimple_bind_vars, there might be other
1823 decls in BLOCK_VARS rendering the GIMPLE_BIND not useless. */
1824 if (block && !BLOCK_NUM_NONLOCALIZED_VARS (block))
1825 for (var = BLOCK_VARS (block); var; var = TREE_CHAIN (var))
1826 if (TREE_CODE (var) == IMPORTED_DECL)
1828 if (var || (block && BLOCK_NUM_NONLOCALIZED_VARS (block)))
1832 gsi_insert_seq_before (gsi, body_seq, GSI_SAME_STMT);
1833 gsi_remove (gsi, false);
1834 data->repeat = true;
1841 /* Helper for remove_useless_stmts_1. Handle GIMPLE_GOTO statements. */
1844 remove_useless_stmts_goto (gimple_stmt_iterator *gsi, struct rus_data *data)
1846 gimple stmt = gsi_stmt (*gsi);
1848 tree dest = gimple_goto_dest (stmt);
1850 data->may_branch = true;
1851 data->last_was_goto = false;
1853 /* Record iterator for last goto expr, so that we can delete it if unnecessary. */
1854 if (TREE_CODE (dest) == LABEL_DECL)
1856 data->last_goto_gsi = *gsi;
1857 data->last_was_goto = true;
1863 /* Helper for remove_useless_stmts_1. Handle GIMPLE_LABEL statements. */
1866 remove_useless_stmts_label (gimple_stmt_iterator *gsi, struct rus_data *data)
1868 gimple stmt = gsi_stmt (*gsi);
1870 tree label = gimple_label_label (stmt);
1872 data->has_label = true;
1874 /* We do want to jump across non-local label receiver code. */
1875 if (DECL_NONLOCAL (label))
1876 data->last_was_goto = false;
1878 else if (data->last_was_goto
1879 && gimple_goto_dest (gsi_stmt (data->last_goto_gsi)) == label)
1881 /* Replace the preceding GIMPLE_GOTO statement with
1882 a GIMPLE_NOP, which will be subsequently removed.
1883 In this way, we avoid invalidating other iterators
1884 active on the statement sequence. */
1885 gsi_replace(&data->last_goto_gsi, gimple_build_nop(), false);
1886 data->last_was_goto = false;
1887 data->repeat = true;
1890 /* ??? Add something here to delete unused labels. */
1896 /* T is CALL_EXPR. Set current_function_calls_* flags. */
1899 notice_special_calls (gimple call)
1901 int flags = gimple_call_flags (call);
1903 if (flags & ECF_MAY_BE_ALLOCA)
1904 cfun->calls_alloca = true;
1905 if (flags & ECF_RETURNS_TWICE)
1906 cfun->calls_setjmp = true;
1910 /* Clear flags set by notice_special_calls. Used by dead code removal
1911 to update the flags. */
1914 clear_special_calls (void)
1916 cfun->calls_alloca = false;
1917 cfun->calls_setjmp = false;
1920 /* Remove useless statements from a statement sequence, and perform
1921 some preliminary simplifications. */
1924 remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *data)
1926 while (!gsi_end_p (*gsi))
1928 gimple stmt = gsi_stmt (*gsi);
1930 switch (gimple_code (stmt))
1933 remove_useless_stmts_cond (gsi, data);
1937 remove_useless_stmts_goto (gsi, data);
1941 remove_useless_stmts_label (gsi, data);
1946 stmt = gsi_stmt (*gsi);
1947 data->last_was_goto = false;
1948 if (stmt_could_throw_p (stmt))
1949 data->may_throw = true;
1955 data->last_was_goto = false;
1961 stmt = gsi_stmt (*gsi);
1962 data->last_was_goto = false;
1963 if (is_gimple_call (stmt))
1964 notice_special_calls (stmt);
1966 /* We used to call update_gimple_call_flags here,
1967 which copied side-effects and nothrows status
1968 from the function decl to the call. In the new
1969 tuplified GIMPLE, the accessors for this information
1970 always consult the function decl, so this copying
1971 is no longer necessary. */
1972 if (stmt_could_throw_p (stmt))
1973 data->may_throw = true;
1979 data->last_was_goto = false;
1980 data->may_branch = true;
1985 remove_useless_stmts_bind (gsi, data);
1989 if (gimple_try_kind (stmt) == GIMPLE_TRY_CATCH)
1990 remove_useless_stmts_tc (gsi, data);
1991 else if (gimple_try_kind (stmt) == GIMPLE_TRY_FINALLY)
1992 remove_useless_stmts_tf (gsi, data);
2002 gsi_remove (gsi, false);
2005 case GIMPLE_OMP_FOR:
2007 gimple_seq pre_body_seq = gimple_omp_for_pre_body (stmt);
2008 gimple_stmt_iterator pre_body_gsi = gsi_start (pre_body_seq);
2010 remove_useless_stmts_1 (&pre_body_gsi, data);
2011 data->last_was_goto = false;
2014 case GIMPLE_OMP_CRITICAL:
2015 case GIMPLE_OMP_CONTINUE:
2016 case GIMPLE_OMP_MASTER:
2017 case GIMPLE_OMP_ORDERED:
2018 case GIMPLE_OMP_SECTION:
2019 case GIMPLE_OMP_SECTIONS:
2020 case GIMPLE_OMP_SINGLE:
2022 gimple_seq body_seq = gimple_omp_body (stmt);
2023 gimple_stmt_iterator body_gsi = gsi_start (body_seq);
2025 remove_useless_stmts_1 (&body_gsi, data);
2026 data->last_was_goto = false;
2031 case GIMPLE_OMP_PARALLEL:
2032 case GIMPLE_OMP_TASK:
2034 /* Make sure the outermost GIMPLE_BIND isn't removed
2036 gimple_seq body_seq = gimple_omp_body (stmt);
2037 gimple bind = gimple_seq_first_stmt (body_seq);
2038 gimple_seq bind_seq = gimple_bind_body (bind);
2039 gimple_stmt_iterator bind_gsi = gsi_start (bind_seq);
2041 remove_useless_stmts_1 (&bind_gsi, data);
2042 data->last_was_goto = false;
2047 case GIMPLE_CHANGE_DYNAMIC_TYPE:
2048 /* If we do not optimize remove GIMPLE_CHANGE_DYNAMIC_TYPE as
2049 expansion is confused about them and we only remove them
2050 during alias computation otherwise. */
2053 data->last_was_goto = false;
2054 gsi_remove (gsi, false);
2060 data->last_was_goto = false;
2067 /* Walk the function tree, removing useless statements and performing
2068 some preliminary simplifications. */
2071 remove_useless_stmts (void)
2073 struct rus_data data;
2075 clear_special_calls ();
2079 gimple_stmt_iterator gsi;
2081 gsi = gsi_start (gimple_body (current_function_decl));
2082 memset (&data, 0, sizeof (data));
2083 remove_useless_stmts_1 (&gsi, &data);
2085 while (data.repeat);
2090 struct gimple_opt_pass pass_remove_useless_stmts =
2094 "useless", /* name */
2096 remove_useless_stmts, /* execute */
2099 0, /* static_pass_number */
2100 TV_NONE, /* tv_id */
2101 PROP_gimple_any, /* properties_required */
2102 0, /* properties_provided */
2103 0, /* properties_destroyed */
2104 0, /* todo_flags_start */
2105 TODO_dump_func /* todo_flags_finish */
2109 /* Remove PHI nodes associated with basic block BB and all edges out of BB. */
2112 remove_phi_nodes_and_edges_for_unreachable_block (basic_block bb)
2114 /* Since this block is no longer reachable, we can just delete all
2115 of its PHI nodes. */
2116 remove_phi_nodes (bb);
2118 /* Remove edges to BB's successors. */
2119 while (EDGE_COUNT (bb->succs) > 0)
2120 remove_edge (EDGE_SUCC (bb, 0));
2124 /* Remove statements of basic block BB. */
2127 remove_bb (basic_block bb)
2129 gimple_stmt_iterator i;
2130 source_location loc = UNKNOWN_LOCATION;
2134 fprintf (dump_file, "Removing basic block %d\n", bb->index);
2135 if (dump_flags & TDF_DETAILS)
2137 dump_bb (bb, dump_file, 0);
2138 fprintf (dump_file, "\n");
2144 struct loop *loop = bb->loop_father;
2146 /* If a loop gets removed, clean up the information associated
2148 if (loop->latch == bb
2149 || loop->header == bb)
2150 free_numbers_of_iterations_estimates_loop (loop);
2153 /* Remove all the instructions in the block. */
2154 if (bb_seq (bb) != NULL)
2156 for (i = gsi_start_bb (bb); !gsi_end_p (i);)
2158 gimple stmt = gsi_stmt (i);
2159 if (gimple_code (stmt) == GIMPLE_LABEL
2160 && (FORCED_LABEL (gimple_label_label (stmt))
2161 || DECL_NONLOCAL (gimple_label_label (stmt))))
2164 gimple_stmt_iterator new_gsi;
2166 /* A non-reachable non-local label may still be referenced.
2167 But it no longer needs to carry the extra semantics of
2169 if (DECL_NONLOCAL (gimple_label_label (stmt)))
2171 DECL_NONLOCAL (gimple_label_label (stmt)) = 0;
2172 FORCED_LABEL (gimple_label_label (stmt)) = 1;
2175 new_bb = bb->prev_bb;
2176 new_gsi = gsi_start_bb (new_bb);
2177 gsi_remove (&i, false);
2178 gsi_insert_before (&new_gsi, stmt, GSI_NEW_STMT);
2182 /* Release SSA definitions if we are in SSA. Note that we
2183 may be called when not in SSA. For example,
2184 final_cleanup calls this function via
2185 cleanup_tree_cfg. */
2186 if (gimple_in_ssa_p (cfun))
2187 release_defs (stmt);
2189 gsi_remove (&i, true);
2192 /* Don't warn for removed gotos. Gotos are often removed due to
2193 jump threading, thus resulting in bogus warnings. Not great,
2194 since this way we lose warnings for gotos in the original
2195 program that are indeed unreachable. */
2196 if (gimple_code (stmt) != GIMPLE_GOTO
2197 && gimple_has_location (stmt)
2199 loc = gimple_location (stmt);
2203 /* If requested, give a warning that the first statement in the
2204 block is unreachable. We walk statements backwards in the
2205 loop above, so the last statement we process is the first statement
2207 if (loc > BUILTINS_LOCATION && LOCATION_LINE (loc) > 0)
2208 warning (OPT_Wunreachable_code, "%Hwill never be executed", &loc);
2210 remove_phi_nodes_and_edges_for_unreachable_block (bb);
2211 bb->il.gimple = NULL;
2215 /* Given a basic block BB ending with COND_EXPR or SWITCH_EXPR, and a
2216 predicate VAL, return the edge that will be taken out of the block.
2217 If VAL does not match a unique edge, NULL is returned. */
2220 find_taken_edge (basic_block bb, tree val)
2224 stmt = last_stmt (bb);
2227 gcc_assert (is_ctrl_stmt (stmt));
2232 if (!is_gimple_min_invariant (val))
2235 if (gimple_code (stmt) == GIMPLE_COND)
2236 return find_taken_edge_cond_expr (bb, val);
2238 if (gimple_code (stmt) == GIMPLE_SWITCH)
2239 return find_taken_edge_switch_expr (bb, val);
2241 if (computed_goto_p (stmt))
2243 /* Only optimize if the argument is a label, if the argument is
2244 not a label then we can not construct a proper CFG.
2246 It may be the case that we only need to allow the LABEL_REF to
2247 appear inside an ADDR_EXPR, but we also allow the LABEL_REF to
2248 appear inside a LABEL_EXPR just to be safe. */
2249 if ((TREE_CODE (val) == ADDR_EXPR || TREE_CODE (val) == LABEL_EXPR)
2250 && TREE_CODE (TREE_OPERAND (val, 0)) == LABEL_DECL)
2251 return find_taken_edge_computed_goto (bb, TREE_OPERAND (val, 0));
2258 /* Given a constant value VAL and the entry block BB to a GOTO_EXPR
2259 statement, determine which of the outgoing edges will be taken out of the
2260 block. Return NULL if either edge may be taken. */
2263 find_taken_edge_computed_goto (basic_block bb, tree val)
2268 dest = label_to_block (val);
2271 e = find_edge (bb, dest);
2272 gcc_assert (e != NULL);
2278 /* Given a constant value VAL and the entry block BB to a COND_EXPR
2279 statement, determine which of the two edges will be taken out of the
2280 block. Return NULL if either edge may be taken. */
2283 find_taken_edge_cond_expr (basic_block bb, tree val)
2285 edge true_edge, false_edge;
2287 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
2289 gcc_assert (TREE_CODE (val) == INTEGER_CST);
2290 return (integer_zerop (val) ? false_edge : true_edge);
2293 /* Given an INTEGER_CST VAL and the entry block BB to a SWITCH_EXPR
2294 statement, determine which edge will be taken out of the block. Return
2295 NULL if any edge may be taken. */
2298 find_taken_edge_switch_expr (basic_block bb, tree val)
2300 basic_block dest_bb;
2305 switch_stmt = last_stmt (bb);
2306 taken_case = find_case_label_for_value (switch_stmt, val);
2307 dest_bb = label_to_block (CASE_LABEL (taken_case));
2309 e = find_edge (bb, dest_bb);
2315 /* Return the CASE_LABEL_EXPR that SWITCH_STMT will take for VAL.
2316 We can make optimal use here of the fact that the case labels are
2317 sorted: We can do a binary search for a case matching VAL. */
2320 find_case_label_for_value (gimple switch_stmt, tree val)
2322 size_t low, high, n = gimple_switch_num_labels (switch_stmt);
2323 tree default_case = gimple_switch_default_label (switch_stmt);
2325 for (low = 0, high = n; high - low > 1; )
2327 size_t i = (high + low) / 2;
2328 tree t = gimple_switch_label (switch_stmt, i);
2331 /* Cache the result of comparing CASE_LOW and val. */
2332 cmp = tree_int_cst_compare (CASE_LOW (t), val);
2339 if (CASE_HIGH (t) == NULL)
2341 /* A singe-valued case label. */
2347 /* A case range. We can only handle integer ranges. */
2348 if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
2353 return default_case;
2357 /* Dump a basic block on stderr. */
2360 gimple_debug_bb (basic_block bb)
2362 gimple_dump_bb (bb, stderr, 0, TDF_VOPS|TDF_MEMSYMS);
2366 /* Dump basic block with index N on stderr. */
2369 gimple_debug_bb_n (int n)
2371 gimple_debug_bb (BASIC_BLOCK (n));
2372 return BASIC_BLOCK (n);
2376 /* Dump the CFG on stderr.
2378 FLAGS are the same used by the tree dumping functions
2379 (see TDF_* in tree-pass.h). */
2382 gimple_debug_cfg (int flags)
2384 gimple_dump_cfg (stderr, flags);
2388 /* Dump the program showing basic block boundaries on the given FILE.
2390 FLAGS are the same used by the tree dumping functions (see TDF_* in
2394 gimple_dump_cfg (FILE *file, int flags)
2396 if (flags & TDF_DETAILS)
2398 const char *funcname
2399 = lang_hooks.decl_printable_name (current_function_decl, 2);
2402 fprintf (file, ";; Function %s\n\n", funcname);
2403 fprintf (file, ";; \n%d basic blocks, %d edges, last basic block %d.\n\n",
2404 n_basic_blocks, n_edges, last_basic_block);
2406 brief_dump_cfg (file);
2407 fprintf (file, "\n");
2410 if (flags & TDF_STATS)
2411 dump_cfg_stats (file);
2413 dump_function_to_file (current_function_decl, file, flags | TDF_BLOCKS);
2417 /* Dump CFG statistics on FILE. */
2420 dump_cfg_stats (FILE *file)
2422 static long max_num_merged_labels = 0;
2423 unsigned long size, total = 0;
2426 const char * const fmt_str = "%-30s%-13s%12s\n";
2427 const char * const fmt_str_1 = "%-30s%13d%11lu%c\n";
2428 const char * const fmt_str_2 = "%-30s%13ld%11lu%c\n";
2429 const char * const fmt_str_3 = "%-43s%11lu%c\n";
2430 const char *funcname
2431 = lang_hooks.decl_printable_name (current_function_decl, 2);
2434 fprintf (file, "\nCFG Statistics for %s\n\n", funcname);
2436 fprintf (file, "---------------------------------------------------------\n");
2437 fprintf (file, fmt_str, "", " Number of ", "Memory");
2438 fprintf (file, fmt_str, "", " instances ", "used ");
2439 fprintf (file, "---------------------------------------------------------\n");
2441 size = n_basic_blocks * sizeof (struct basic_block_def);
2443 fprintf (file, fmt_str_1, "Basic blocks", n_basic_blocks,
2444 SCALE (size), LABEL (size));
2448 num_edges += EDGE_COUNT (bb->succs);
2449 size = num_edges * sizeof (struct edge_def);
2451 fprintf (file, fmt_str_2, "Edges", num_edges, SCALE (size), LABEL (size));
2453 fprintf (file, "---------------------------------------------------------\n");
2454 fprintf (file, fmt_str_3, "Total memory used by CFG data", SCALE (total),
2456 fprintf (file, "---------------------------------------------------------\n");
2457 fprintf (file, "\n");
2459 if (cfg_stats.num_merged_labels > max_num_merged_labels)
2460 max_num_merged_labels = cfg_stats.num_merged_labels;
2462 fprintf (file, "Coalesced label blocks: %ld (Max so far: %ld)\n",
2463 cfg_stats.num_merged_labels, max_num_merged_labels);
2465 fprintf (file, "\n");
2469 /* Dump CFG statistics on stderr. Keep extern so that it's always
2470 linked in the final executable. */
2473 debug_cfg_stats (void)
2475 dump_cfg_stats (stderr);
2479 /* Dump the flowgraph to a .vcg FILE. */
2482 gimple_cfg2vcg (FILE *file)
2487 const char *funcname
2488 = lang_hooks.decl_printable_name (current_function_decl, 2);
2490 /* Write the file header. */
2491 fprintf (file, "graph: { title: \"%s\"\n", funcname);
2492 fprintf (file, "node: { title: \"ENTRY\" label: \"ENTRY\" }\n");
2493 fprintf (file, "node: { title: \"EXIT\" label: \"EXIT\" }\n");
2495 /* Write blocks and edges. */
2496 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
2498 fprintf (file, "edge: { sourcename: \"ENTRY\" targetname: \"%d\"",
2501 if (e->flags & EDGE_FAKE)
2502 fprintf (file, " linestyle: dotted priority: 10");
2504 fprintf (file, " linestyle: solid priority: 100");
2506 fprintf (file, " }\n");
2512 enum gimple_code head_code, end_code;
2513 const char *head_name, *end_name;
2516 gimple first = first_stmt (bb);
2517 gimple last = last_stmt (bb);
2521 head_code = gimple_code (first);
2522 head_name = gimple_code_name[head_code];
2523 head_line = get_lineno (first);
2526 head_name = "no-statement";
2530 end_code = gimple_code (last);
2531 end_name = gimple_code_name[end_code];
2532 end_line = get_lineno (last);
2535 end_name = "no-statement";
2537 fprintf (file, "node: { title: \"%d\" label: \"#%d\\n%s (%d)\\n%s (%d)\"}\n",
2538 bb->index, bb->index, head_name, head_line, end_name,
2541 FOR_EACH_EDGE (e, ei, bb->succs)
2543 if (e->dest == EXIT_BLOCK_PTR)
2544 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"EXIT\"", bb->index);
2546 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"%d\"", bb->index, e->dest->index);
2548 if (e->flags & EDGE_FAKE)
2549 fprintf (file, " priority: 10 linestyle: dotted");
2551 fprintf (file, " priority: 100 linestyle: solid");
2553 fprintf (file, " }\n");
2556 if (bb->next_bb != EXIT_BLOCK_PTR)
2560 fputs ("}\n\n", file);
2565 /*---------------------------------------------------------------------------
2566 Miscellaneous helpers
2567 ---------------------------------------------------------------------------*/
2569 /* Return true if T represents a stmt that always transfers control. */
2572 is_ctrl_stmt (gimple t)
2574 return gimple_code (t) == GIMPLE_COND
2575 || gimple_code (t) == GIMPLE_SWITCH
2576 || gimple_code (t) == GIMPLE_GOTO
2577 || gimple_code (t) == GIMPLE_RETURN
2578 || gimple_code (t) == GIMPLE_RESX;
2582 /* Return true if T is a statement that may alter the flow of control
2583 (e.g., a call to a non-returning function). */
2586 is_ctrl_altering_stmt (gimple t)
2590 if (is_gimple_call (t))
2592 int flags = gimple_call_flags (t);
2594 /* A non-pure/const call alters flow control if the current
2595 function has nonlocal labels. */
2596 if (!(flags & (ECF_CONST | ECF_PURE))
2597 && cfun->has_nonlocal_label)
2600 /* A call also alters control flow if it does not return. */
2601 if (gimple_call_flags (t) & ECF_NORETURN)
2605 /* OpenMP directives alter control flow. */
2606 if (is_gimple_omp (t))
2609 /* If a statement can throw, it alters control flow. */
2610 return stmt_can_throw_internal (t);
2614 /* Return true if T is a simple local goto. */
2617 simple_goto_p (gimple t)
2619 return (gimple_code (t) == GIMPLE_GOTO
2620 && TREE_CODE (gimple_goto_dest (t)) == LABEL_DECL);
2624 /* Return true if T can make an abnormal transfer of control flow.
2625 Transfers of control flow associated with EH are excluded. */
2628 stmt_can_make_abnormal_goto (gimple t)
2630 if (computed_goto_p (t))
2632 if (is_gimple_call (t))
2633 return gimple_has_side_effects (t) && cfun->has_nonlocal_label;
2638 /* Return true if STMT should start a new basic block. PREV_STMT is
2639 the statement preceding STMT. It is used when STMT is a label or a
2640 case label. Labels should only start a new basic block if their
2641 previous statement wasn't a label. Otherwise, sequence of labels
2642 would generate unnecessary basic blocks that only contain a single
2646 stmt_starts_bb_p (gimple stmt, gimple prev_stmt)
2651 /* Labels start a new basic block only if the preceding statement
2652 wasn't a label of the same type. This prevents the creation of
2653 consecutive blocks that have nothing but a single label. */
2654 if (gimple_code (stmt) == GIMPLE_LABEL)
2656 /* Nonlocal and computed GOTO targets always start a new block. */
2657 if (DECL_NONLOCAL (gimple_label_label (stmt))
2658 || FORCED_LABEL (gimple_label_label (stmt)))
2661 if (prev_stmt && gimple_code (prev_stmt) == GIMPLE_LABEL)
2663 if (DECL_NONLOCAL (gimple_label_label (prev_stmt)))
2666 cfg_stats.num_merged_labels++;
2677 /* Return true if T should end a basic block. */
2680 stmt_ends_bb_p (gimple t)
2682 return is_ctrl_stmt (t) || is_ctrl_altering_stmt (t);
2685 /* Remove block annotations and other data structures. */
2688 delete_tree_cfg_annotations (void)
2690 label_to_block_map = NULL;
2694 /* Return the first statement in basic block BB. */
2697 first_stmt (basic_block bb)
2699 gimple_stmt_iterator i = gsi_start_bb (bb);
2700 return !gsi_end_p (i) ? gsi_stmt (i) : NULL;
2703 /* Return the last statement in basic block BB. */
2706 last_stmt (basic_block bb)
2708 gimple_stmt_iterator b = gsi_last_bb (bb);
2709 return !gsi_end_p (b) ? gsi_stmt (b) : NULL;
2712 /* Return the last statement of an otherwise empty block. Return NULL
2713 if the block is totally empty, or if it contains more than one
2717 last_and_only_stmt (basic_block bb)
2719 gimple_stmt_iterator i = gsi_last_bb (bb);
2725 last = gsi_stmt (i);
2730 /* Empty statements should no longer appear in the instruction stream.
2731 Everything that might have appeared before should be deleted by
2732 remove_useless_stmts, and the optimizers should just gsi_remove
2733 instead of smashing with build_empty_stmt.
2735 Thus the only thing that should appear here in a block containing
2736 one executable statement is a label. */
2737 prev = gsi_stmt (i);
2738 if (gimple_code (prev) == GIMPLE_LABEL)
2744 /* Reinstall those PHI arguments queued in OLD_EDGE to NEW_EDGE. */
2747 reinstall_phi_args (edge new_edge, edge old_edge)
2749 edge_var_map_vector v;
2752 gimple_stmt_iterator phis;
2754 v = redirect_edge_var_map_vector (old_edge);
2758 for (i = 0, phis = gsi_start_phis (new_edge->dest);
2759 VEC_iterate (edge_var_map, v, i, vm) && !gsi_end_p (phis);
2760 i++, gsi_next (&phis))
2762 gimple phi = gsi_stmt (phis);
2763 tree result = redirect_edge_var_map_result (vm);
2764 tree arg = redirect_edge_var_map_def (vm);
2766 gcc_assert (result == gimple_phi_result (phi));
2768 add_phi_arg (phi, arg, new_edge);
2771 redirect_edge_var_map_clear (old_edge);
2774 /* Returns the basic block after which the new basic block created
2775 by splitting edge EDGE_IN should be placed. Tries to keep the new block
2776 near its "logical" location. This is of most help to humans looking
2777 at debugging dumps. */
2780 split_edge_bb_loc (edge edge_in)
2782 basic_block dest = edge_in->dest;
2784 if (dest->prev_bb && find_edge (dest->prev_bb, dest))
2785 return edge_in->src;
2787 return dest->prev_bb;
2790 /* Split a (typically critical) edge EDGE_IN. Return the new block.
2791 Abort on abnormal edges. */
2794 gimple_split_edge (edge edge_in)
2796 basic_block new_bb, after_bb, dest;
2799 /* Abnormal edges cannot be split. */
2800 gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
2802 dest = edge_in->dest;
2804 after_bb = split_edge_bb_loc (edge_in);
2806 new_bb = create_empty_bb (after_bb);
2807 new_bb->frequency = EDGE_FREQUENCY (edge_in);
2808 new_bb->count = edge_in->count;
2809 new_edge = make_edge (new_bb, dest, EDGE_FALLTHRU);
2810 new_edge->probability = REG_BR_PROB_BASE;
2811 new_edge->count = edge_in->count;
2813 e = redirect_edge_and_branch (edge_in, new_bb);
2814 gcc_assert (e == edge_in);
2815 reinstall_phi_args (new_edge, e);
2820 /* Callback for walk_tree, check that all elements with address taken are
2821 properly noticed as such. The DATA is an int* that is 1 if TP was seen
2822 inside a PHI node. */
2825 verify_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
2832 /* Check operand N for being valid GIMPLE and give error MSG if not. */
2833 #define CHECK_OP(N, MSG) \
2834 do { if (!is_gimple_val (TREE_OPERAND (t, N))) \
2835 { error (MSG); return TREE_OPERAND (t, N); }} while (0)
2837 switch (TREE_CODE (t))
2840 if (SSA_NAME_IN_FREE_LIST (t))
2842 error ("SSA name in freelist but still referenced");
2848 x = TREE_OPERAND (t, 0);
2849 if (!is_gimple_reg (x) && !is_gimple_min_invariant (x))
2851 error ("Indirect reference's operand is not a register or a constant.");
2857 x = fold (ASSERT_EXPR_COND (t));
2858 if (x == boolean_false_node)
2860 error ("ASSERT_EXPR with an always-false condition");
2866 error ("MODIFY_EXPR not expected while having tuples.");
2872 bool old_side_effects;
2874 bool new_side_effects;
2876 gcc_assert (is_gimple_address (t));
2878 old_constant = TREE_CONSTANT (t);
2879 old_side_effects = TREE_SIDE_EFFECTS (t);
2881 recompute_tree_invariant_for_addr_expr (t);
2882 new_side_effects = TREE_SIDE_EFFECTS (t);
2883 new_constant = TREE_CONSTANT (t);
2885 if (old_constant != new_constant)
2887 error ("constant not recomputed when ADDR_EXPR changed");
2890 if (old_side_effects != new_side_effects)
2892 error ("side effects not recomputed when ADDR_EXPR changed");
2896 /* Skip any references (they will be checked when we recurse down the
2897 tree) and ensure that any variable used as a prefix is marked
2899 for (x = TREE_OPERAND (t, 0);
2900 handled_component_p (x);
2901 x = TREE_OPERAND (x, 0))
2904 if (!(TREE_CODE (x) == VAR_DECL
2905 || TREE_CODE (x) == PARM_DECL
2906 || TREE_CODE (x) == RESULT_DECL))
2908 if (!TREE_ADDRESSABLE (x))
2910 error ("address taken, but ADDRESSABLE bit not set");
2913 if (DECL_GIMPLE_REG_P (x))
2915 error ("DECL_GIMPLE_REG_P set on a variable with address taken");
2923 x = COND_EXPR_COND (t);
2924 if (!INTEGRAL_TYPE_P (TREE_TYPE (x)))
2926 error ("non-integral used in condition");
2929 if (!is_gimple_condexpr (x))
2931 error ("invalid conditional operand");
2936 case NON_LVALUE_EXPR:
2940 case FIX_TRUNC_EXPR:
2945 case TRUTH_NOT_EXPR:
2946 CHECK_OP (0, "invalid operand to unary operator");
2953 case ARRAY_RANGE_REF:
2955 case VIEW_CONVERT_EXPR:
2956 /* We have a nest of references. Verify that each of the operands
2957 that determine where to reference is either a constant or a variable,
2958 verify that the base is valid, and then show we've already checked
2960 while (handled_component_p (t))
2962 if (TREE_CODE (t) == COMPONENT_REF && TREE_OPERAND (t, 2))
2963 CHECK_OP (2, "invalid COMPONENT_REF offset operator");
2964 else if (TREE_CODE (t) == ARRAY_REF
2965 || TREE_CODE (t) == ARRAY_RANGE_REF)
2967 CHECK_OP (1, "invalid array index");
2968 if (TREE_OPERAND (t, 2))
2969 CHECK_OP (2, "invalid array lower bound");
2970 if (TREE_OPERAND (t, 3))
2971 CHECK_OP (3, "invalid array stride");
2973 else if (TREE_CODE (t) == BIT_FIELD_REF)
2975 if (!host_integerp (TREE_OPERAND (t, 1), 1)
2976 || !host_integerp (TREE_OPERAND (t, 2), 1))
2978 error ("invalid position or size operand to BIT_FIELD_REF");
2981 else if (INTEGRAL_TYPE_P (TREE_TYPE (t))
2982 && (TYPE_PRECISION (TREE_TYPE (t))
2983 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
2985 error ("integral result type precision does not match "
2986 "field size of BIT_FIELD_REF");
2989 if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
2990 && (GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (t)))
2991 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
2993 error ("mode precision of non-integral result does not "
2994 "match field size of BIT_FIELD_REF");
2999 t = TREE_OPERAND (t, 0);
3002 if (!is_gimple_min_invariant (t) && !is_gimple_lvalue (t))
3004 error ("invalid reference prefix");
3011 /* PLUS_EXPR and MINUS_EXPR don't work on pointers, they should be done using
3012 POINTER_PLUS_EXPR. */
3013 if (POINTER_TYPE_P (TREE_TYPE (t)))
3015 error ("invalid operand to plus/minus, type is a pointer");
3018 CHECK_OP (0, "invalid operand to binary operator");
3019 CHECK_OP (1, "invalid operand to binary operator");
3022 case POINTER_PLUS_EXPR:
3023 /* Check to make sure the first operand is a pointer or reference type. */
3024 if (!POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 0))))
3026 error ("invalid operand to pointer plus, first operand is not a pointer");
3029 /* Check to make sure the second operand is an integer with type of
3031 if (!useless_type_conversion_p (sizetype,
3032 TREE_TYPE (TREE_OPERAND (t, 1))))
3034 error ("invalid operand to pointer plus, second operand is not an "
3035 "integer with type of sizetype.");
3045 case UNORDERED_EXPR:
3054 case TRUNC_DIV_EXPR:
3056 case FLOOR_DIV_EXPR:
3057 case ROUND_DIV_EXPR:
3058 case TRUNC_MOD_EXPR:
3060 case FLOOR_MOD_EXPR:
3061 case ROUND_MOD_EXPR:
3063 case EXACT_DIV_EXPR:
3073 CHECK_OP (0, "invalid operand to binary operator");
3074 CHECK_OP (1, "invalid operand to binary operator");
3078 if (TREE_CONSTANT (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
3091 /* Verify if EXPR is either a GIMPLE ID or a GIMPLE indirect reference.
3092 Returns true if there is an error, otherwise false. */
3095 verify_types_in_gimple_min_lval (tree expr)
3099 if (is_gimple_id (expr))
3102 if (!INDIRECT_REF_P (expr)
3103 && TREE_CODE (expr) != TARGET_MEM_REF)
3105 error ("invalid expression for min lvalue");
3109 /* TARGET_MEM_REFs are strange beasts. */
3110 if (TREE_CODE (expr) == TARGET_MEM_REF)
3113 op = TREE_OPERAND (expr, 0);
3114 if (!is_gimple_val (op))
3116 error ("invalid operand in indirect reference");
3117 debug_generic_stmt (op);
3120 if (!useless_type_conversion_p (TREE_TYPE (expr),
3121 TREE_TYPE (TREE_TYPE (op))))
3123 error ("type mismatch in indirect reference");
3124 debug_generic_stmt (TREE_TYPE (expr));
3125 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3132 /* Verify if EXPR is a valid GIMPLE reference expression. Returns true
3133 if there is an error, otherwise false. */
3136 verify_types_in_gimple_reference (tree expr)
3138 while (handled_component_p (expr))
3140 tree op = TREE_OPERAND (expr, 0);
3142 if (TREE_CODE (expr) == ARRAY_REF
3143 || TREE_CODE (expr) == ARRAY_RANGE_REF)
3145 if (!is_gimple_val (TREE_OPERAND (expr, 1))
3146 || (TREE_OPERAND (expr, 2)
3147 && !is_gimple_val (TREE_OPERAND (expr, 2)))
3148 || (TREE_OPERAND (expr, 3)
3149 && !is_gimple_val (TREE_OPERAND (expr, 3))))
3151 error ("invalid operands to array reference");
3152 debug_generic_stmt (expr);
3157 /* Verify if the reference array element types are compatible. */
3158 if (TREE_CODE (expr) == ARRAY_REF
3159 && !useless_type_conversion_p (TREE_TYPE (expr),
3160 TREE_TYPE (TREE_TYPE (op))))
3162 error ("type mismatch in array reference");
3163 debug_generic_stmt (TREE_TYPE (expr));
3164 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3167 if (TREE_CODE (expr) == ARRAY_RANGE_REF
3168 && !useless_type_conversion_p (TREE_TYPE (TREE_TYPE (expr)),
3169 TREE_TYPE (TREE_TYPE (op))))
3171 error ("type mismatch in array range reference");
3172 debug_generic_stmt (TREE_TYPE (TREE_TYPE (expr)));
3173 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3177 if ((TREE_CODE (expr) == REALPART_EXPR
3178 || TREE_CODE (expr) == IMAGPART_EXPR)
3179 && !useless_type_conversion_p (TREE_TYPE (expr),
3180 TREE_TYPE (TREE_TYPE (op))))
3182 error ("type mismatch in real/imagpart reference");
3183 debug_generic_stmt (TREE_TYPE (expr));
3184 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3188 if (TREE_CODE (expr) == COMPONENT_REF
3189 && !useless_type_conversion_p (TREE_TYPE (expr),
3190 TREE_TYPE (TREE_OPERAND (expr, 1))))
3192 error ("type mismatch in component reference");
3193 debug_generic_stmt (TREE_TYPE (expr));
3194 debug_generic_stmt (TREE_TYPE (TREE_OPERAND (expr, 1)));
3198 /* For VIEW_CONVERT_EXPRs which are allowed here, too, there
3199 is nothing to verify. Gross mismatches at most invoke
3200 undefined behavior. */
3201 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR
3202 && !handled_component_p (op))
3208 return verify_types_in_gimple_min_lval (expr);
3211 /* Returns true if there is one pointer type in TYPE_POINTER_TO (SRC_OBJ)
3212 list of pointer-to types that is trivially convertible to DEST. */
3215 one_pointer_to_useless_type_conversion_p (tree dest, tree src_obj)
3219 if (!TYPE_POINTER_TO (src_obj))
3222 for (src = TYPE_POINTER_TO (src_obj); src; src = TYPE_NEXT_PTR_TO (src))
3223 if (useless_type_conversion_p (dest, src))
3229 /* Return true if TYPE1 is a fixed-point type and if conversions to and
3230 from TYPE2 can be handled by FIXED_CONVERT_EXPR. */
3233 valid_fixed_convert_types_p (tree type1, tree type2)
3235 return (FIXED_POINT_TYPE_P (type1)
3236 && (INTEGRAL_TYPE_P (type2)
3237 || SCALAR_FLOAT_TYPE_P (type2)
3238 || FIXED_POINT_TYPE_P (type2)));
3241 /* Verify the contents of a GIMPLE_CALL STMT. Returns true when there
3242 is a problem, otherwise false. */
3245 verify_gimple_call (gimple stmt)
3247 tree fn = gimple_call_fn (stmt);
3250 if (!POINTER_TYPE_P (TREE_TYPE (fn))
3251 || (TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != FUNCTION_TYPE
3252 && TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != METHOD_TYPE))
3254 error ("non-function in gimple call");
3258 if (gimple_call_lhs (stmt)
3259 && !is_gimple_lvalue (gimple_call_lhs (stmt)))
3261 error ("invalid LHS in gimple call");
3265 fntype = TREE_TYPE (TREE_TYPE (fn));
3266 if (gimple_call_lhs (stmt)
3267 && !useless_type_conversion_p (TREE_TYPE (gimple_call_lhs (stmt)),
3269 /* ??? At least C++ misses conversions at assignments from
3270 void * call results.
3271 ??? Java is completely off. Especially with functions
3272 returning java.lang.Object.
3273 For now simply allow arbitrary pointer type conversions. */
3274 && !(POINTER_TYPE_P (TREE_TYPE (gimple_call_lhs (stmt)))
3275 && POINTER_TYPE_P (TREE_TYPE (fntype))))
3277 error ("invalid conversion in gimple call");
3278 debug_generic_stmt (TREE_TYPE (gimple_call_lhs (stmt)));
3279 debug_generic_stmt (TREE_TYPE (fntype));
3283 /* ??? The C frontend passes unpromoted arguments in case it
3284 didn't see a function declaration before the call. So for now
3285 leave the call arguments unverified. Once we gimplify
3286 unit-at-a-time we have a chance to fix this. */
3291 /* Verifies the gimple comparison with the result type TYPE and
3292 the operands OP0 and OP1. */
3295 verify_gimple_comparison (tree type, tree op0, tree op1)
3297 tree op0_type = TREE_TYPE (op0);
3298 tree op1_type = TREE_TYPE (op1);
3300 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3302 error ("invalid operands in gimple comparison");
3306 /* For comparisons we do not have the operations type as the
3307 effective type the comparison is carried out in. Instead
3308 we require that either the first operand is trivially
3309 convertible into the second, or the other way around.
3310 The resulting type of a comparison may be any integral type.
3311 Because we special-case pointers to void we allow
3312 comparisons of pointers with the same mode as well. */
3313 if ((!useless_type_conversion_p (op0_type, op1_type)
3314 && !useless_type_conversion_p (op1_type, op0_type)
3315 && (!POINTER_TYPE_P (op0_type)
3316 || !POINTER_TYPE_P (op1_type)
3317 || TYPE_MODE (op0_type) != TYPE_MODE (op1_type)))
3318 || !INTEGRAL_TYPE_P (type))
3320 error ("type mismatch in comparison expression");
3321 debug_generic_expr (type);
3322 debug_generic_expr (op0_type);
3323 debug_generic_expr (op1_type);
3330 /* Verify a gimple assignment statement STMT with an unary rhs.
3331 Returns true if anything is wrong. */
3334 verify_gimple_assign_unary (gimple stmt)
3336 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3337 tree lhs = gimple_assign_lhs (stmt);
3338 tree lhs_type = TREE_TYPE (lhs);
3339 tree rhs1 = gimple_assign_rhs1 (stmt);
3340 tree rhs1_type = TREE_TYPE (rhs1);
3342 if (!is_gimple_reg (lhs)
3344 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3346 error ("non-register as LHS of unary operation");
3350 if (!is_gimple_val (rhs1))
3352 error ("invalid operand in unary operation");
3356 /* First handle conversions. */
3361 /* Allow conversions between integral types and pointers only if
3362 there is no sign or zero extension involved.
3363 For targets were the precision of sizetype doesn't match that
3364 of pointers we need to allow arbitrary conversions from and
3366 if ((POINTER_TYPE_P (lhs_type)
3367 && INTEGRAL_TYPE_P (rhs1_type)
3368 && (TYPE_PRECISION (lhs_type) >= TYPE_PRECISION (rhs1_type)
3369 || rhs1_type == sizetype))
3370 || (POINTER_TYPE_P (rhs1_type)
3371 && INTEGRAL_TYPE_P (lhs_type)
3372 && (TYPE_PRECISION (rhs1_type) >= TYPE_PRECISION (lhs_type)
3373 || lhs_type == sizetype)))
3376 /* Allow conversion from integer to offset type and vice versa. */
3377 if ((TREE_CODE (lhs_type) == OFFSET_TYPE
3378 && TREE_CODE (rhs1_type) == INTEGER_TYPE)
3379 || (TREE_CODE (lhs_type) == INTEGER_TYPE
3380 && TREE_CODE (rhs1_type) == OFFSET_TYPE))
3383 /* Otherwise assert we are converting between types of the
3385 if (INTEGRAL_TYPE_P (lhs_type) != INTEGRAL_TYPE_P (rhs1_type))
3387 error ("invalid types in nop conversion");
3388 debug_generic_expr (lhs_type);
3389 debug_generic_expr (rhs1_type);
3396 case FIXED_CONVERT_EXPR:
3398 if (!valid_fixed_convert_types_p (lhs_type, rhs1_type)
3399 && !valid_fixed_convert_types_p (rhs1_type, lhs_type))
3401 error ("invalid types in fixed-point conversion");
3402 debug_generic_expr (lhs_type);
3403 debug_generic_expr (rhs1_type);
3412 if (!INTEGRAL_TYPE_P (rhs1_type) || !SCALAR_FLOAT_TYPE_P (lhs_type))
3414 error ("invalid types in conversion to floating point");
3415 debug_generic_expr (lhs_type);
3416 debug_generic_expr (rhs1_type);
3423 case FIX_TRUNC_EXPR:
3425 if (!INTEGRAL_TYPE_P (lhs_type) || !SCALAR_FLOAT_TYPE_P (rhs1_type))
3427 error ("invalid types in conversion to integer");
3428 debug_generic_expr (lhs_type);
3429 debug_generic_expr (rhs1_type);
3436 case VEC_UNPACK_HI_EXPR:
3437 case VEC_UNPACK_LO_EXPR:
3438 case REDUC_MAX_EXPR:
3439 case REDUC_MIN_EXPR:
3440 case REDUC_PLUS_EXPR:
3441 case VEC_UNPACK_FLOAT_HI_EXPR:
3442 case VEC_UNPACK_FLOAT_LO_EXPR:
3446 case TRUTH_NOT_EXPR:
3451 case NON_LVALUE_EXPR:
3459 /* For the remaining codes assert there is no conversion involved. */
3460 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3462 error ("non-trivial conversion in unary operation");
3463 debug_generic_expr (lhs_type);
3464 debug_generic_expr (rhs1_type);
3471 /* Verify a gimple assignment statement STMT with a binary rhs.
3472 Returns true if anything is wrong. */
3475 verify_gimple_assign_binary (gimple stmt)
3477 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3478 tree lhs = gimple_assign_lhs (stmt);
3479 tree lhs_type = TREE_TYPE (lhs);
3480 tree rhs1 = gimple_assign_rhs1 (stmt);
3481 tree rhs1_type = TREE_TYPE (rhs1);
3482 tree rhs2 = gimple_assign_rhs2 (stmt);
3483 tree rhs2_type = TREE_TYPE (rhs2);
3485 if (!is_gimple_reg (lhs)
3487 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3489 error ("non-register as LHS of binary operation");
3493 if (!is_gimple_val (rhs1)
3494 || !is_gimple_val (rhs2))
3496 error ("invalid operands in binary operation");
3500 /* First handle operations that involve different types. */
3505 if (TREE_CODE (lhs_type) != COMPLEX_TYPE
3506 || !(INTEGRAL_TYPE_P (rhs1_type)
3507 || SCALAR_FLOAT_TYPE_P (rhs1_type))
3508 || !(INTEGRAL_TYPE_P (rhs2_type)
3509 || SCALAR_FLOAT_TYPE_P (rhs2_type)))
3511 error ("type mismatch in complex expression");
3512 debug_generic_expr (lhs_type);
3513 debug_generic_expr (rhs1_type);
3514 debug_generic_expr (rhs2_type);
3526 /* Shifts and rotates are ok on integral types, fixed point
3527 types and integer vector types. */
3528 if ((!INTEGRAL_TYPE_P (rhs1_type)
3529 && !FIXED_POINT_TYPE_P (rhs1_type)
3530 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3531 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE))
3532 || (!INTEGRAL_TYPE_P (rhs2_type)
3533 /* Vector shifts of vectors are also ok. */
3534 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3535 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE
3536 && TREE_CODE (rhs2_type) == VECTOR_TYPE
3537 && TREE_CODE (TREE_TYPE (rhs2_type)) == INTEGER_TYPE))
3538 || !useless_type_conversion_p (lhs_type, rhs1_type))
3540 error ("type mismatch in shift expression");
3541 debug_generic_expr (lhs_type);
3542 debug_generic_expr (rhs1_type);
3543 debug_generic_expr (rhs2_type);
3550 case VEC_LSHIFT_EXPR:
3551 case VEC_RSHIFT_EXPR:
3553 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3554 || !(INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))
3555 || FIXED_POINT_TYPE_P (TREE_TYPE (rhs1_type)))
3556 || (!INTEGRAL_TYPE_P (rhs2_type)
3557 && (TREE_CODE (rhs2_type) != VECTOR_TYPE
3558 || !INTEGRAL_TYPE_P (TREE_TYPE (rhs2_type))))
3559 || !useless_type_conversion_p (lhs_type, rhs1_type))
3561 error ("type mismatch in vector shift expression");
3562 debug_generic_expr (lhs_type);
3563 debug_generic_expr (rhs1_type);
3564 debug_generic_expr (rhs2_type);
3573 /* We use regular PLUS_EXPR for vectors.
3574 ??? This just makes the checker happy and may not be what is
3576 if (TREE_CODE (lhs_type) == VECTOR_TYPE
3577 && POINTER_TYPE_P (TREE_TYPE (lhs_type)))
3579 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3580 || TREE_CODE (rhs2_type) != VECTOR_TYPE)
3582 error ("invalid non-vector operands to vector valued plus");
3585 lhs_type = TREE_TYPE (lhs_type);
3586 rhs1_type = TREE_TYPE (rhs1_type);
3587 rhs2_type = TREE_TYPE (rhs2_type);
3588 /* PLUS_EXPR is commutative, so we might end up canonicalizing
3589 the pointer to 2nd place. */
3590 if (POINTER_TYPE_P (rhs2_type))
3592 tree tem = rhs1_type;
3593 rhs1_type = rhs2_type;
3596 goto do_pointer_plus_expr_check;
3602 if (POINTER_TYPE_P (lhs_type)
3603 || POINTER_TYPE_P (rhs1_type)
3604 || POINTER_TYPE_P (rhs2_type))
3606 error ("invalid (pointer) operands to plus/minus");
3610 /* Continue with generic binary expression handling. */
3614 case POINTER_PLUS_EXPR:
3616 do_pointer_plus_expr_check:
3617 if (!POINTER_TYPE_P (rhs1_type)
3618 || !useless_type_conversion_p (lhs_type, rhs1_type)
3619 || !useless_type_conversion_p (sizetype, rhs2_type))
3621 error ("type mismatch in pointer plus expression");
3622 debug_generic_stmt (lhs_type);
3623 debug_generic_stmt (rhs1_type);
3624 debug_generic_stmt (rhs2_type);
3631 case TRUTH_ANDIF_EXPR:
3632 case TRUTH_ORIF_EXPR:
3635 case TRUTH_AND_EXPR:
3637 case TRUTH_XOR_EXPR:
3639 /* We allow any kind of integral typed argument and result. */
3640 if (!INTEGRAL_TYPE_P (rhs1_type)
3641 || !INTEGRAL_TYPE_P (rhs2_type)
3642 || !INTEGRAL_TYPE_P (lhs_type))
3644 error ("type mismatch in binary truth expression");
3645 debug_generic_expr (lhs_type);
3646 debug_generic_expr (rhs1_type);
3647 debug_generic_expr (rhs2_type);
3660 case UNORDERED_EXPR:
3668 /* Comparisons are also binary, but the result type is not
3669 connected to the operand types. */
3670 return verify_gimple_comparison (lhs_type, rhs1, rhs2);
3672 case WIDEN_SUM_EXPR:
3673 case WIDEN_MULT_EXPR:
3674 case VEC_WIDEN_MULT_HI_EXPR:
3675 case VEC_WIDEN_MULT_LO_EXPR:
3676 case VEC_PACK_TRUNC_EXPR:
3677 case VEC_PACK_SAT_EXPR:
3678 case VEC_PACK_FIX_TRUNC_EXPR:
3679 case VEC_EXTRACT_EVEN_EXPR:
3680 case VEC_EXTRACT_ODD_EXPR:
3681 case VEC_INTERLEAVE_HIGH_EXPR:
3682 case VEC_INTERLEAVE_LOW_EXPR:
3687 case TRUNC_DIV_EXPR:
3689 case FLOOR_DIV_EXPR:
3690 case ROUND_DIV_EXPR:
3691 case TRUNC_MOD_EXPR:
3693 case FLOOR_MOD_EXPR:
3694 case ROUND_MOD_EXPR:
3696 case EXACT_DIV_EXPR:
3702 /* Continue with generic binary expression handling. */
3709 if (!useless_type_conversion_p (lhs_type, rhs1_type)
3710 || !useless_type_conversion_p (lhs_type, rhs2_type))
3712 error ("type mismatch in binary expression");
3713 debug_generic_stmt (lhs_type);
3714 debug_generic_stmt (rhs1_type);
3715 debug_generic_stmt (rhs2_type);
3722 /* Verify a gimple assignment statement STMT with a single rhs.
3723 Returns true if anything is wrong. */
3726 verify_gimple_assign_single (gimple stmt)
3728 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3729 tree lhs = gimple_assign_lhs (stmt);
3730 tree lhs_type = TREE_TYPE (lhs);
3731 tree rhs1 = gimple_assign_rhs1 (stmt);
3732 tree rhs1_type = TREE_TYPE (rhs1);
3735 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3737 error ("non-trivial conversion at assignment");
3738 debug_generic_expr (lhs_type);
3739 debug_generic_expr (rhs1_type);
3743 if (handled_component_p (lhs))
3744 res |= verify_types_in_gimple_reference (lhs);
3746 /* Special codes we cannot handle via their class. */
3751 tree op = TREE_OPERAND (rhs1, 0);
3752 if (!is_gimple_addressable (op))
3754 error ("invalid operand in unary expression");
3758 if (!one_pointer_to_useless_type_conversion_p (lhs_type,
3761 error ("type mismatch in address expression");
3762 debug_generic_stmt (lhs_type);
3763 debug_generic_stmt (TYPE_POINTER_TO (TREE_TYPE (op)));
3767 return verify_types_in_gimple_reference (op);
3774 case ALIGN_INDIRECT_REF:
3775 case MISALIGNED_INDIRECT_REF:
3777 case ARRAY_RANGE_REF:
3778 case VIEW_CONVERT_EXPR:
3781 case TARGET_MEM_REF:
3782 if (!is_gimple_reg (lhs)
3783 && is_gimple_reg_type (TREE_TYPE (lhs)))
3785 error ("invalid rhs for gimple memory store");
3786 debug_generic_stmt (lhs);
3787 debug_generic_stmt (rhs1);
3790 return res || verify_types_in_gimple_reference (rhs1);
3802 /* tcc_declaration */
3807 if (!is_gimple_reg (lhs)
3808 && !is_gimple_reg (rhs1)
3809 && is_gimple_reg_type (TREE_TYPE (lhs)))
3811 error ("invalid rhs for gimple memory store");
3812 debug_generic_stmt (lhs);
3813 debug_generic_stmt (rhs1);
3822 case WITH_SIZE_EXPR:
3825 case POLYNOMIAL_CHREC:
3828 case REALIGN_LOAD_EXPR:
3838 /* Verify the contents of a GIMPLE_ASSIGN STMT. Returns true when there
3839 is a problem, otherwise false. */
3842 verify_gimple_assign (gimple stmt)
3844 switch (gimple_assign_rhs_class (stmt))
3846 case GIMPLE_SINGLE_RHS:
3847 return verify_gimple_assign_single (stmt);
3849 case GIMPLE_UNARY_RHS:
3850 return verify_gimple_assign_unary (stmt);
3852 case GIMPLE_BINARY_RHS:
3853 return verify_gimple_assign_binary (stmt);
3860 /* Verify the contents of a GIMPLE_RETURN STMT. Returns true when there
3861 is a problem, otherwise false. */
3864 verify_gimple_return (gimple stmt)
3866 tree op = gimple_return_retval (stmt);
3867 tree restype = TREE_TYPE (TREE_TYPE (cfun->decl));
3869 /* We cannot test for present return values as we do not fix up missing
3870 return values from the original source. */
3874 if (!is_gimple_val (op)
3875 && TREE_CODE (op) != RESULT_DECL)
3877 error ("invalid operand in return statement");
3878 debug_generic_stmt (op);
3882 if (!useless_type_conversion_p (restype, TREE_TYPE (op))
3883 /* ??? With C++ we can have the situation that the result
3884 decl is a reference type while the return type is an aggregate. */
3885 && !(TREE_CODE (op) == RESULT_DECL
3886 && TREE_CODE (TREE_TYPE (op)) == REFERENCE_TYPE
3887 && useless_type_conversion_p (restype, TREE_TYPE (TREE_TYPE (op)))))
3889 error ("invalid conversion in return statement");
3890 debug_generic_stmt (restype);
3891 debug_generic_stmt (TREE_TYPE (op));
3899 /* Verify the contents of a GIMPLE_GOTO STMT. Returns true when there
3900 is a problem, otherwise false. */
3903 verify_gimple_goto (gimple stmt)
3905 tree dest = gimple_goto_dest (stmt);
3907 /* ??? We have two canonical forms of direct goto destinations, a
3908 bare LABEL_DECL and an ADDR_EXPR of a LABEL_DECL. */
3909 if (TREE_CODE (dest) != LABEL_DECL
3910 && (!is_gimple_val (dest)
3911 || !POINTER_TYPE_P (TREE_TYPE (dest))))
3913 error ("goto destination is neither a label nor a pointer");
3920 /* Verify the contents of a GIMPLE_SWITCH STMT. Returns true when there
3921 is a problem, otherwise false. */
3924 verify_gimple_switch (gimple stmt)
3926 if (!is_gimple_val (gimple_switch_index (stmt)))
3928 error ("invalid operand to switch statement");
3929 debug_generic_stmt (gimple_switch_index (stmt));
3937 /* Verify the contents of a GIMPLE_PHI. Returns true if there is a problem,
3938 and false otherwise. */
3941 verify_gimple_phi (gimple stmt)
3943 tree type = TREE_TYPE (gimple_phi_result (stmt));
3946 if (!is_gimple_variable (gimple_phi_result (stmt)))
3948 error ("Invalid PHI result");
3952 for (i = 0; i < gimple_phi_num_args (stmt); i++)
3954 tree arg = gimple_phi_arg_def (stmt, i);
3955 if ((is_gimple_reg (gimple_phi_result (stmt))
3956 && !is_gimple_val (arg))
3957 || (!is_gimple_reg (gimple_phi_result (stmt))
3958 && !is_gimple_addressable (arg)))
3960 error ("Invalid PHI argument");
3961 debug_generic_stmt (arg);
3964 if (!useless_type_conversion_p (type, TREE_TYPE (arg)))
3966 error ("Incompatible types in PHI argument %u", i);
3967 debug_generic_stmt (type);
3968 debug_generic_stmt (TREE_TYPE (arg));
3977 /* Verify the GIMPLE statement STMT. Returns true if there is an
3978 error, otherwise false. */
3981 verify_types_in_gimple_stmt (gimple stmt)
3983 if (is_gimple_omp (stmt))
3985 /* OpenMP directives are validated by the FE and never operated
3986 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
3987 non-gimple expressions when the main index variable has had
3988 its address taken. This does not affect the loop itself
3989 because the header of an GIMPLE_OMP_FOR is merely used to determine
3990 how to setup the parallel iteration. */
3994 switch (gimple_code (stmt))
3997 return verify_gimple_assign (stmt);
4000 return TREE_CODE (gimple_label_label (stmt)) != LABEL_DECL;
4003 return verify_gimple_call (stmt);
4006 return verify_gimple_comparison (boolean_type_node,
4007 gimple_cond_lhs (stmt),
4008 gimple_cond_rhs (stmt));
4011 return verify_gimple_goto (stmt);
4014 return verify_gimple_switch (stmt);
4017 return verify_gimple_return (stmt);
4022 case GIMPLE_CHANGE_DYNAMIC_TYPE:
4023 return (!is_gimple_val (gimple_cdt_location (stmt))
4024 || !POINTER_TYPE_P (TREE_TYPE (gimple_cdt_location (stmt))));
4027 return verify_gimple_phi (stmt);
4029 /* Tuples that do not have tree operands. */
4032 case GIMPLE_PREDICT:
4040 /* Verify the GIMPLE statements inside the sequence STMTS. */
4043 verify_types_in_gimple_seq_2 (gimple_seq stmts)
4045 gimple_stmt_iterator ittr;
4048 for (ittr = gsi_start (stmts); !gsi_end_p (ittr); gsi_next (&ittr))
4050 gimple stmt = gsi_stmt (ittr);
4052 switch (gimple_code (stmt))
4055 err |= verify_types_in_gimple_seq_2 (gimple_bind_body (stmt));
4059 err |= verify_types_in_gimple_seq_2 (gimple_try_eval (stmt));
4060 err |= verify_types_in_gimple_seq_2 (gimple_try_cleanup (stmt));
4063 case GIMPLE_EH_FILTER:
4064 err |= verify_types_in_gimple_seq_2 (gimple_eh_filter_failure (stmt));
4068 err |= verify_types_in_gimple_seq_2 (gimple_catch_handler (stmt));
4073 bool err2 = verify_types_in_gimple_stmt (stmt);
4075 debug_gimple_stmt (stmt);
4085 /* Verify the GIMPLE statements inside the statement list STMTS. */
4088 verify_types_in_gimple_seq (gimple_seq stmts)
4090 if (verify_types_in_gimple_seq_2 (stmts))
4091 internal_error ("verify_gimple failed");
4095 /* Verify STMT, return true if STMT is not in GIMPLE form.
4096 TODO: Implement type checking. */
4099 verify_stmt (gimple_stmt_iterator *gsi)
4102 struct walk_stmt_info wi;
4103 bool last_in_block = gsi_one_before_end_p (*gsi);
4104 gimple stmt = gsi_stmt (*gsi);
4106 if (is_gimple_omp (stmt))
4108 /* OpenMP directives are validated by the FE and never operated
4109 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4110 non-gimple expressions when the main index variable has had
4111 its address taken. This does not affect the loop itself
4112 because the header of an GIMPLE_OMP_FOR is merely used to determine
4113 how to setup the parallel iteration. */
4117 /* FIXME. The C frontend passes unpromoted arguments in case it
4118 didn't see a function declaration before the call. */
4119 if (is_gimple_call (stmt))
4123 if (!is_gimple_call_addr (gimple_call_fn (stmt)))
4125 error ("invalid function in call statement");
4129 decl = gimple_call_fndecl (stmt);
4131 && TREE_CODE (decl) == FUNCTION_DECL
4132 && DECL_LOOPING_CONST_OR_PURE_P (decl)
4133 && (!DECL_PURE_P (decl))
4134 && (!TREE_READONLY (decl)))
4136 error ("invalid pure const state for function");
4141 memset (&wi, 0, sizeof (wi));
4142 addr = walk_gimple_op (gsi_stmt (*gsi), verify_expr, &wi);
4145 debug_generic_expr (addr);
4146 inform (input_location, "in statement");
4147 debug_gimple_stmt (stmt);
4151 /* If the statement is marked as part of an EH region, then it is
4152 expected that the statement could throw. Verify that when we
4153 have optimizations that simplify statements such that we prove
4154 that they cannot throw, that we update other data structures
4156 if (lookup_stmt_eh_region (stmt) >= 0)
4158 if (!stmt_could_throw_p (stmt))
4160 error ("statement marked for throw, but doesn%'t");
4163 if (!last_in_block && stmt_can_throw_internal (stmt))
4165 error ("statement marked for throw in middle of block");
4173 debug_gimple_stmt (stmt);
4178 /* Return true when the T can be shared. */
4181 tree_node_can_be_shared (tree t)
4183 if (IS_TYPE_OR_DECL_P (t)
4184 || is_gimple_min_invariant (t)
4185 || TREE_CODE (t) == SSA_NAME
4186 || t == error_mark_node
4187 || TREE_CODE (t) == IDENTIFIER_NODE)
4190 if (TREE_CODE (t) == CASE_LABEL_EXPR)
4193 while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4194 && is_gimple_min_invariant (TREE_OPERAND (t, 1)))
4195 || TREE_CODE (t) == COMPONENT_REF
4196 || TREE_CODE (t) == REALPART_EXPR
4197 || TREE_CODE (t) == IMAGPART_EXPR)
4198 t = TREE_OPERAND (t, 0);
4207 /* Called via walk_gimple_stmt. Verify tree sharing. */
4210 verify_node_sharing (tree *tp, int *walk_subtrees, void *data)
4212 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
4213 struct pointer_set_t *visited = (struct pointer_set_t *) wi->info;
4215 if (tree_node_can_be_shared (*tp))
4217 *walk_subtrees = false;
4221 if (pointer_set_insert (visited, *tp))
4228 static bool eh_error_found;
4230 verify_eh_throw_stmt_node (void **slot, void *data)
4232 struct throw_stmt_node *node = (struct throw_stmt_node *)*slot;
4233 struct pointer_set_t *visited = (struct pointer_set_t *) data;
4235 if (!pointer_set_contains (visited, node->stmt))
4237 error ("Dead STMT in EH table");
4238 debug_gimple_stmt (node->stmt);
4239 eh_error_found = true;
4245 /* Verify the GIMPLE statements in every basic block. */
4251 gimple_stmt_iterator gsi;
4253 struct pointer_set_t *visited, *visited_stmts;
4255 struct walk_stmt_info wi;
4257 timevar_push (TV_TREE_STMT_VERIFY);
4258 visited = pointer_set_create ();
4259 visited_stmts = pointer_set_create ();
4261 memset (&wi, 0, sizeof (wi));
4262 wi.info = (void *) visited;
4269 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4271 phi = gsi_stmt (gsi);
4272 pointer_set_insert (visited_stmts, phi);
4273 if (gimple_bb (phi) != bb)
4275 error ("gimple_bb (phi) is set to a wrong basic block");
4279 for (i = 0; i < gimple_phi_num_args (phi); i++)
4281 tree t = gimple_phi_arg_def (phi, i);
4286 error ("missing PHI def");
4287 debug_gimple_stmt (phi);
4291 /* Addressable variables do have SSA_NAMEs but they
4292 are not considered gimple values. */
4293 else if (TREE_CODE (t) != SSA_NAME
4294 && TREE_CODE (t) != FUNCTION_DECL
4295 && !is_gimple_min_invariant (t))
4297 error ("PHI argument is not a GIMPLE value");
4298 debug_gimple_stmt (phi);
4299 debug_generic_expr (t);
4303 addr = walk_tree (&t, verify_node_sharing, visited, NULL);
4306 error ("incorrect sharing of tree nodes");
4307 debug_gimple_stmt (phi);
4308 debug_generic_expr (addr);
4314 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); )
4316 gimple stmt = gsi_stmt (gsi);
4318 if (gimple_code (stmt) == GIMPLE_WITH_CLEANUP_EXPR
4319 || gimple_code (stmt) == GIMPLE_BIND)
4321 error ("invalid GIMPLE statement");
4322 debug_gimple_stmt (stmt);
4326 pointer_set_insert (visited_stmts, stmt);
4328 if (gimple_bb (stmt) != bb)
4330 error ("gimple_bb (stmt) is set to a wrong basic block");
4334 if (gimple_code (stmt) == GIMPLE_LABEL)
4336 tree decl = gimple_label_label (stmt);
4337 int uid = LABEL_DECL_UID (decl);
4340 || VEC_index (basic_block, label_to_block_map, uid) != bb)
4342 error ("incorrect entry in label_to_block_map.\n");
4347 err |= verify_stmt (&gsi);
4348 addr = walk_gimple_op (gsi_stmt (gsi), verify_node_sharing, &wi);
4351 error ("incorrect sharing of tree nodes");
4352 debug_gimple_stmt (stmt);
4353 debug_generic_expr (addr);
4360 eh_error_found = false;
4361 if (get_eh_throw_stmt_table (cfun))
4362 htab_traverse (get_eh_throw_stmt_table (cfun),
4363 verify_eh_throw_stmt_node,
4366 if (err | eh_error_found)
4367 internal_error ("verify_stmts failed");
4369 pointer_set_destroy (visited);
4370 pointer_set_destroy (visited_stmts);
4371 verify_histograms ();
4372 timevar_pop (TV_TREE_STMT_VERIFY);
4376 /* Verifies that the flow information is OK. */
4379 gimple_verify_flow_info (void)
4383 gimple_stmt_iterator gsi;
4388 if (ENTRY_BLOCK_PTR->il.gimple)
4390 error ("ENTRY_BLOCK has IL associated with it");
4394 if (EXIT_BLOCK_PTR->il.gimple)
4396 error ("EXIT_BLOCK has IL associated with it");
4400 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4401 if (e->flags & EDGE_FALLTHRU)
4403 error ("fallthru to exit from bb %d", e->src->index);
4409 bool found_ctrl_stmt = false;
4413 /* Skip labels on the start of basic block. */
4414 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4417 gimple prev_stmt = stmt;
4419 stmt = gsi_stmt (gsi);
4421 if (gimple_code (stmt) != GIMPLE_LABEL)
4424 label = gimple_label_label (stmt);
4425 if (prev_stmt && DECL_NONLOCAL (label))
4427 error ("nonlocal label ");
4428 print_generic_expr (stderr, label, 0);
4429 fprintf (stderr, " is not first in a sequence of labels in bb %d",
4434 if (label_to_block (label) != bb)
4437 print_generic_expr (stderr, label, 0);
4438 fprintf (stderr, " to block does not match in bb %d",
4443 if (decl_function_context (label) != current_function_decl)
4446 print_generic_expr (stderr, label, 0);
4447 fprintf (stderr, " has incorrect context in bb %d",
4453 /* Verify that body of basic block BB is free of control flow. */
4454 for (; !gsi_end_p (gsi); gsi_next (&gsi))
4456 gimple stmt = gsi_stmt (gsi);
4458 if (found_ctrl_stmt)
4460 error ("control flow in the middle of basic block %d",
4465 if (stmt_ends_bb_p (stmt))
4466 found_ctrl_stmt = true;
4468 if (gimple_code (stmt) == GIMPLE_LABEL)
4471 print_generic_expr (stderr, gimple_label_label (stmt), 0);
4472 fprintf (stderr, " in the middle of basic block %d", bb->index);
4477 gsi = gsi_last_bb (bb);
4478 if (gsi_end_p (gsi))
4481 stmt = gsi_stmt (gsi);
4483 err |= verify_eh_edges (stmt);
4485 if (is_ctrl_stmt (stmt))
4487 FOR_EACH_EDGE (e, ei, bb->succs)
4488 if (e->flags & EDGE_FALLTHRU)
4490 error ("fallthru edge after a control statement in bb %d",
4496 if (gimple_code (stmt) != GIMPLE_COND)
4498 /* Verify that there are no edges with EDGE_TRUE/FALSE_FLAG set
4499 after anything else but if statement. */
4500 FOR_EACH_EDGE (e, ei, bb->succs)
4501 if (e->flags & (EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))
4503 error ("true/false edge after a non-GIMPLE_COND in bb %d",
4509 switch (gimple_code (stmt))
4516 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
4520 || !(true_edge->flags & EDGE_TRUE_VALUE)
4521 || !(false_edge->flags & EDGE_FALSE_VALUE)
4522 || (true_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4523 || (false_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4524 || EDGE_COUNT (bb->succs) >= 3)
4526 error ("wrong outgoing edge flags at end of bb %d",
4534 if (simple_goto_p (stmt))
4536 error ("explicit goto at end of bb %d", bb->index);
4541 /* FIXME. We should double check that the labels in the
4542 destination blocks have their address taken. */
4543 FOR_EACH_EDGE (e, ei, bb->succs)
4544 if ((e->flags & (EDGE_FALLTHRU | EDGE_TRUE_VALUE
4545 | EDGE_FALSE_VALUE))
4546 || !(e->flags & EDGE_ABNORMAL))
4548 error ("wrong outgoing edge flags at end of bb %d",
4556 if (!single_succ_p (bb)
4557 || (single_succ_edge (bb)->flags
4558 & (EDGE_FALLTHRU | EDGE_ABNORMAL
4559 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4561 error ("wrong outgoing edge flags at end of bb %d", bb->index);
4564 if (single_succ (bb) != EXIT_BLOCK_PTR)
4566 error ("return edge does not point to exit in bb %d",
4578 n = gimple_switch_num_labels (stmt);
4580 /* Mark all the destination basic blocks. */
4581 for (i = 0; i < n; ++i)
4583 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4584 basic_block label_bb = label_to_block (lab);
4585 gcc_assert (!label_bb->aux || label_bb->aux == (void *)1);
4586 label_bb->aux = (void *)1;
4589 /* Verify that the case labels are sorted. */
4590 prev = gimple_switch_label (stmt, 0);
4591 for (i = 1; i < n; ++i)
4593 tree c = gimple_switch_label (stmt, i);
4596 error ("found default case not at the start of "
4602 && !tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c)))
4604 error ("case labels not sorted: ");
4605 print_generic_expr (stderr, prev, 0);
4606 fprintf (stderr," is greater than ");
4607 print_generic_expr (stderr, c, 0);
4608 fprintf (stderr," but comes before it.\n");
4613 /* VRP will remove the default case if it can prove it will
4614 never be executed. So do not verify there always exists
4615 a default case here. */
4617 FOR_EACH_EDGE (e, ei, bb->succs)
4621 error ("extra outgoing edge %d->%d",
4622 bb->index, e->dest->index);
4626 e->dest->aux = (void *)2;
4627 if ((e->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL
4628 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4630 error ("wrong outgoing edge flags at end of bb %d",
4636 /* Check that we have all of them. */
4637 for (i = 0; i < n; ++i)
4639 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4640 basic_block label_bb = label_to_block (lab);
4642 if (label_bb->aux != (void *)2)
4644 error ("missing edge %i->%i", bb->index, label_bb->index);
4649 FOR_EACH_EDGE (e, ei, bb->succs)
4650 e->dest->aux = (void *)0;
4657 if (dom_info_state (CDI_DOMINATORS) >= DOM_NO_FAST_QUERY)
4658 verify_dominators (CDI_DOMINATORS);
4664 /* Updates phi nodes after creating a forwarder block joined
4665 by edge FALLTHRU. */
4668 gimple_make_forwarder_block (edge fallthru)
4672 basic_block dummy, bb;
4674 gimple_stmt_iterator gsi;
4676 dummy = fallthru->src;
4677 bb = fallthru->dest;
4679 if (single_pred_p (bb))
4682 /* If we redirected a branch we must create new PHI nodes at the
4684 for (gsi = gsi_start_phis (dummy); !gsi_end_p (gsi); gsi_next (&gsi))
4686 gimple phi, new_phi;
4688 phi = gsi_stmt (gsi);
4689 var = gimple_phi_result (phi);
4690 new_phi = create_phi_node (var, bb);
4691 SSA_NAME_DEF_STMT (var) = new_phi;
4692 gimple_phi_set_result (phi, make_ssa_name (SSA_NAME_VAR (var), phi));
4693 add_phi_arg (new_phi, gimple_phi_result (phi), fallthru);
4696 /* Add the arguments we have stored on edges. */
4697 FOR_EACH_EDGE (e, ei, bb->preds)
4702 flush_pending_stmts (e);
4707 /* Return a non-special label in the head of basic block BLOCK.
4708 Create one if it doesn't exist. */
4711 gimple_block_label (basic_block bb)
4713 gimple_stmt_iterator i, s = gsi_start_bb (bb);
4718 for (i = s; !gsi_end_p (i); first = false, gsi_next (&i))
4720 stmt = gsi_stmt (i);
4721 if (gimple_code (stmt) != GIMPLE_LABEL)
4723 label = gimple_label_label (stmt);
4724 if (!DECL_NONLOCAL (label))
4727 gsi_move_before (&i, &s);
4732 label = create_artificial_label ();
4733 stmt = gimple_build_label (label);
4734 gsi_insert_before (&s, stmt, GSI_NEW_STMT);
4739 /* Attempt to perform edge redirection by replacing a possibly complex
4740 jump instruction by a goto or by removing the jump completely.
4741 This can apply only if all edges now point to the same block. The
4742 parameters and return values are equivalent to
4743 redirect_edge_and_branch. */
4746 gimple_try_redirect_by_replacing_jump (edge e, basic_block target)
4748 basic_block src = e->src;
4749 gimple_stmt_iterator i;
4752 /* We can replace or remove a complex jump only when we have exactly
4754 if (EDGE_COUNT (src->succs) != 2
4755 /* Verify that all targets will be TARGET. Specifically, the
4756 edge that is not E must also go to TARGET. */
4757 || EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)
4760 i = gsi_last_bb (src);
4764 stmt = gsi_stmt (i);
4766 if (gimple_code (stmt) == GIMPLE_COND || gimple_code (stmt) == GIMPLE_SWITCH)
4768 gsi_remove (&i, true);
4769 e = ssa_redirect_edge (e, target);
4770 e->flags = EDGE_FALLTHRU;
4778 /* Redirect E to DEST. Return NULL on failure. Otherwise, return the
4779 edge representing the redirected branch. */
4782 gimple_redirect_edge_and_branch (edge e, basic_block dest)
4784 basic_block bb = e->src;
4785 gimple_stmt_iterator gsi;
4789 if (e->flags & EDGE_ABNORMAL)
4792 if (e->src != ENTRY_BLOCK_PTR
4793 && (ret = gimple_try_redirect_by_replacing_jump (e, dest)))
4796 if (e->dest == dest)
4799 gsi = gsi_last_bb (bb);
4800 stmt = gsi_end_p (gsi) ? NULL : gsi_stmt (gsi);
4802 switch (stmt ? gimple_code (stmt) : ERROR_MARK)
4805 /* For COND_EXPR, we only need to redirect the edge. */
4809 /* No non-abnormal edges should lead from a non-simple goto, and
4810 simple ones should be represented implicitly. */
4815 tree label = gimple_block_label (dest);
4816 tree cases = get_cases_for_edge (e, stmt);
4818 /* If we have a list of cases associated with E, then use it
4819 as it's a lot faster than walking the entire case vector. */
4822 edge e2 = find_edge (e->src, dest);
4829 CASE_LABEL (cases) = label;
4830 cases = TREE_CHAIN (cases);
4833 /* If there was already an edge in the CFG, then we need
4834 to move all the cases associated with E to E2. */
4837 tree cases2 = get_cases_for_edge (e2, stmt);
4839 TREE_CHAIN (last) = TREE_CHAIN (cases2);
4840 TREE_CHAIN (cases2) = first;
4845 size_t i, n = gimple_switch_num_labels (stmt);
4847 for (i = 0; i < n; i++)
4849 tree elt = gimple_switch_label (stmt, i);
4850 if (label_to_block (CASE_LABEL (elt)) == e->dest)
4851 CASE_LABEL (elt) = label;
4859 gsi_remove (&gsi, true);
4860 e->flags |= EDGE_FALLTHRU;
4863 case GIMPLE_OMP_RETURN:
4864 case GIMPLE_OMP_CONTINUE:
4865 case GIMPLE_OMP_SECTIONS_SWITCH:
4866 case GIMPLE_OMP_FOR:
4867 /* The edges from OMP constructs can be simply redirected. */
4871 /* Otherwise it must be a fallthru edge, and we don't need to
4872 do anything besides redirecting it. */
4873 gcc_assert (e->flags & EDGE_FALLTHRU);
4877 /* Update/insert PHI nodes as necessary. */
4879 /* Now update the edges in the CFG. */
4880 e = ssa_redirect_edge (e, dest);
4885 /* Returns true if it is possible to remove edge E by redirecting
4886 it to the destination of the other edge from E->src. */
4889 gimple_can_remove_branch_p (const_edge e)
4891 if (e->flags & EDGE_ABNORMAL)
4897 /* Simple wrapper, as we can always redirect fallthru edges. */
4900 gimple_redirect_edge_and_branch_force (edge e, basic_block dest)
4902 e = gimple_redirect_edge_and_branch (e, dest);
4909 /* Splits basic block BB after statement STMT (but at least after the
4910 labels). If STMT is NULL, BB is split just after the labels. */
4913 gimple_split_block (basic_block bb, void *stmt)
4915 gimple_stmt_iterator gsi;
4916 gimple_stmt_iterator gsi_tgt;
4923 new_bb = create_empty_bb (bb);
4925 /* Redirect the outgoing edges. */
4926 new_bb->succs = bb->succs;
4928 FOR_EACH_EDGE (e, ei, new_bb->succs)
4931 if (stmt && gimple_code ((gimple) stmt) == GIMPLE_LABEL)
4934 /* Move everything from GSI to the new basic block. */
4935 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4937 act = gsi_stmt (gsi);
4938 if (gimple_code (act) == GIMPLE_LABEL)
4951 if (gsi_end_p (gsi))
4954 /* Split the statement list - avoid re-creating new containers as this
4955 brings ugly quadratic memory consumption in the inliner.
4956 (We are still quadratic since we need to update stmt BB pointers,
4958 list = gsi_split_seq_before (&gsi);
4959 set_bb_seq (new_bb, list);
4960 for (gsi_tgt = gsi_start (list);
4961 !gsi_end_p (gsi_tgt); gsi_next (&gsi_tgt))
4962 gimple_set_bb (gsi_stmt (gsi_tgt), new_bb);
4968 /* Moves basic block BB after block AFTER. */
4971 gimple_move_block_after (basic_block bb, basic_block after)
4973 if (bb->prev_bb == after)
4977 link_block (bb, after);
4983 /* Return true if basic_block can be duplicated. */
4986 gimple_can_duplicate_bb_p (const_basic_block bb ATTRIBUTE_UNUSED)
4991 /* Create a duplicate of the basic block BB. NOTE: This does not
4992 preserve SSA form. */
4995 gimple_duplicate_bb (basic_block bb)
4998 gimple_stmt_iterator gsi, gsi_tgt;
4999 gimple_seq phis = phi_nodes (bb);
5000 gimple phi, stmt, copy;
5002 new_bb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb);
5004 /* Copy the PHI nodes. We ignore PHI node arguments here because
5005 the incoming edges have not been setup yet. */
5006 for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
5008 phi = gsi_stmt (gsi);
5009 copy = create_phi_node (gimple_phi_result (phi), new_bb);
5010 create_new_def_for (gimple_phi_result (copy), copy,
5011 gimple_phi_result_ptr (copy));
5014 gsi_tgt = gsi_start_bb (new_bb);
5015 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5017 def_operand_p def_p;
5018 ssa_op_iter op_iter;
5021 stmt = gsi_stmt (gsi);
5022 if (gimple_code (stmt) == GIMPLE_LABEL)
5025 /* Create a new copy of STMT and duplicate STMT's virtual
5027 copy = gimple_copy (stmt);
5028 gsi_insert_after (&gsi_tgt, copy, GSI_NEW_STMT);
5029 region = lookup_stmt_eh_region (stmt);
5031 add_stmt_to_eh_region (copy, region);
5032 gimple_duplicate_stmt_histograms (cfun, copy, cfun, stmt);
5034 /* Create new names for all the definitions created by COPY and
5035 add replacement mappings for each new name. */
5036 FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS)
5037 create_new_def_for (DEF_FROM_PTR (def_p), copy, def_p);
5043 /* Adds phi node arguments for edge E_COPY after basic block duplication. */
5046 add_phi_args_after_copy_edge (edge e_copy)
5048 basic_block bb, bb_copy = e_copy->src, dest;
5051 gimple phi, phi_copy;
5053 gimple_stmt_iterator psi, psi_copy;
5055 if (gimple_seq_empty_p (phi_nodes (e_copy->dest)))
5058 bb = bb_copy->flags & BB_DUPLICATED ? get_bb_original (bb_copy) : bb_copy;
5060 if (e_copy->dest->flags & BB_DUPLICATED)
5061 dest = get_bb_original (e_copy->dest);
5063 dest = e_copy->dest;
5065 e = find_edge (bb, dest);
5068 /* During loop unrolling the target of the latch edge is copied.
5069 In this case we are not looking for edge to dest, but to
5070 duplicated block whose original was dest. */
5071 FOR_EACH_EDGE (e, ei, bb->succs)
5073 if ((e->dest->flags & BB_DUPLICATED)
5074 && get_bb_original (e->dest) == dest)
5078 gcc_assert (e != NULL);
5081 for (psi = gsi_start_phis (e->dest),
5082 psi_copy = gsi_start_phis (e_copy->dest);
5084 gsi_next (&psi), gsi_next (&psi_copy))
5086 phi = gsi_stmt (psi);
5087 phi_copy = gsi_stmt (psi_copy);
5088 def = PHI_ARG_DEF_FROM_EDGE (phi, e);
5089 add_phi_arg (phi_copy, def, e_copy);
5094 /* Basic block BB_COPY was created by code duplication. Add phi node
5095 arguments for edges going out of BB_COPY. The blocks that were
5096 duplicated have BB_DUPLICATED set. */
5099 add_phi_args_after_copy_bb (basic_block bb_copy)
5104 FOR_EACH_EDGE (e_copy, ei, bb_copy->succs)
5106 add_phi_args_after_copy_edge (e_copy);
5110 /* Blocks in REGION_COPY array of length N_REGION were created by
5111 duplication of basic blocks. Add phi node arguments for edges
5112 going from these blocks. If E_COPY is not NULL, also add
5113 phi node arguments for its destination.*/
5116 add_phi_args_after_copy (basic_block *region_copy, unsigned n_region,
5121 for (i = 0; i < n_region; i++)
5122 region_copy[i]->flags |= BB_DUPLICATED;
5124 for (i = 0; i < n_region; i++)
5125 add_phi_args_after_copy_bb (region_copy[i]);
5127 add_phi_args_after_copy_edge (e_copy);
5129 for (i = 0; i < n_region; i++)
5130 region_copy[i]->flags &= ~BB_DUPLICATED;
5133 /* Duplicates a REGION (set of N_REGION basic blocks) with just a single
5134 important exit edge EXIT. By important we mean that no SSA name defined
5135 inside region is live over the other exit edges of the region. All entry
5136 edges to the region must go to ENTRY->dest. The edge ENTRY is redirected
5137 to the duplicate of the region. SSA form, dominance and loop information
5138 is updated. The new basic blocks are stored to REGION_COPY in the same
5139 order as they had in REGION, provided that REGION_COPY is not NULL.
5140 The function returns false if it is unable to copy the region,
5144 gimple_duplicate_sese_region (edge entry, edge exit,
5145 basic_block *region, unsigned n_region,
5146 basic_block *region_copy)
5149 bool free_region_copy = false, copying_header = false;
5150 struct loop *loop = entry->dest->loop_father;
5152 VEC (basic_block, heap) *doms;
5154 int total_freq = 0, entry_freq = 0;
5155 gcov_type total_count = 0, entry_count = 0;
5157 if (!can_copy_bbs_p (region, n_region))
5160 /* Some sanity checking. Note that we do not check for all possible
5161 missuses of the functions. I.e. if you ask to copy something weird,
5162 it will work, but the state of structures probably will not be
5164 for (i = 0; i < n_region; i++)
5166 /* We do not handle subloops, i.e. all the blocks must belong to the
5168 if (region[i]->loop_father != loop)
5171 if (region[i] != entry->dest
5172 && region[i] == loop->header)
5176 set_loop_copy (loop, loop);
5178 /* In case the function is used for loop header copying (which is the primary
5179 use), ensure that EXIT and its copy will be new latch and entry edges. */
5180 if (loop->header == entry->dest)
5182 copying_header = true;
5183 set_loop_copy (loop, loop_outer (loop));
5185 if (!dominated_by_p (CDI_DOMINATORS, loop->latch, exit->src))
5188 for (i = 0; i < n_region; i++)
5189 if (region[i] != exit->src
5190 && dominated_by_p (CDI_DOMINATORS, region[i], exit->src))
5196 region_copy = XNEWVEC (basic_block, n_region);
5197 free_region_copy = true;
5200 gcc_assert (!need_ssa_update_p (cfun));
5202 /* Record blocks outside the region that are dominated by something
5205 initialize_original_copy_tables ();
5207 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5209 if (entry->dest->count)
5211 total_count = entry->dest->count;
5212 entry_count = entry->count;
5213 /* Fix up corner cases, to avoid division by zero or creation of negative
5215 if (entry_count > total_count)
5216 entry_count = total_count;
5220 total_freq = entry->dest->frequency;
5221 entry_freq = EDGE_FREQUENCY (entry);
5222 /* Fix up corner cases, to avoid division by zero or creation of negative
5224 if (total_freq == 0)
5226 else if (entry_freq > total_freq)
5227 entry_freq = total_freq;
5230 copy_bbs (region, n_region, region_copy, &exit, 1, &exit_copy, loop,
5231 split_edge_bb_loc (entry));
5234 scale_bbs_frequencies_gcov_type (region, n_region,
5235 total_count - entry_count,
5237 scale_bbs_frequencies_gcov_type (region_copy, n_region, entry_count,
5242 scale_bbs_frequencies_int (region, n_region, total_freq - entry_freq,
5244 scale_bbs_frequencies_int (region_copy, n_region, entry_freq, total_freq);
5249 loop->header = exit->dest;
5250 loop->latch = exit->src;
5253 /* Redirect the entry and add the phi node arguments. */
5254 redirected = redirect_edge_and_branch (entry, get_bb_copy (entry->dest));
5255 gcc_assert (redirected != NULL);
5256 flush_pending_stmts (entry);
5258 /* Concerning updating of dominators: We must recount dominators
5259 for entry block and its copy. Anything that is outside of the
5260 region, but was dominated by something inside needs recounting as
5262 set_immediate_dominator (CDI_DOMINATORS, entry->dest, entry->src);
5263 VEC_safe_push (basic_block, heap, doms, get_bb_original (entry->dest));
5264 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5265 VEC_free (basic_block, heap, doms);
5267 /* Add the other PHI node arguments. */
5268 add_phi_args_after_copy (region_copy, n_region, NULL);
5270 /* Update the SSA web. */
5271 update_ssa (TODO_update_ssa);
5273 if (free_region_copy)
5276 free_original_copy_tables ();
5280 /* Duplicates REGION consisting of N_REGION blocks. The new blocks
5281 are stored to REGION_COPY in the same order in that they appear
5282 in REGION, if REGION_COPY is not NULL. ENTRY is the entry to
5283 the region, EXIT an exit from it. The condition guarding EXIT
5284 is moved to ENTRY. Returns true if duplication succeeds, false
5310 gimple_duplicate_sese_tail (edge entry ATTRIBUTE_UNUSED, edge exit ATTRIBUTE_UNUSED,
5311 basic_block *region ATTRIBUTE_UNUSED, unsigned n_region ATTRIBUTE_UNUSED,
5312 basic_block *region_copy ATTRIBUTE_UNUSED)
5315 bool free_region_copy = false;
5316 struct loop *loop = exit->dest->loop_father;
5317 struct loop *orig_loop = entry->dest->loop_father;
5318 basic_block switch_bb, entry_bb, nentry_bb;
5319 VEC (basic_block, heap) *doms;
5320 int total_freq = 0, exit_freq = 0;
5321 gcov_type total_count = 0, exit_count = 0;
5322 edge exits[2], nexits[2], e;
5323 gimple_stmt_iterator gsi;
5327 gcc_assert (EDGE_COUNT (exit->src->succs) == 2);
5329 exits[1] = EDGE_SUCC (exit->src, EDGE_SUCC (exit->src, 0) == exit);
5331 if (!can_copy_bbs_p (region, n_region))
5334 /* Some sanity checking. Note that we do not check for all possible
5335 missuses of the functions. I.e. if you ask to copy something weird
5336 (e.g., in the example, if there is a jump from inside to the middle
5337 of some_code, or come_code defines some of the values used in cond)
5338 it will work, but the resulting code will not be correct. */
5339 for (i = 0; i < n_region; i++)
5341 /* We do not handle subloops, i.e. all the blocks must belong to the
5343 if (region[i]->loop_father != orig_loop)
5346 if (region[i] == orig_loop->latch)
5350 initialize_original_copy_tables ();
5351 set_loop_copy (orig_loop, loop);
5355 region_copy = XNEWVEC (basic_block, n_region);
5356 free_region_copy = true;
5359 gcc_assert (!need_ssa_update_p (cfun));
5361 /* Record blocks outside the region that are dominated by something
5363 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5365 if (exit->src->count)
5367 total_count = exit->src->count;
5368 exit_count = exit->count;
5369 /* Fix up corner cases, to avoid division by zero or creation of negative
5371 if (exit_count > total_count)
5372 exit_count = total_count;
5376 total_freq = exit->src->frequency;
5377 exit_freq = EDGE_FREQUENCY (exit);
5378 /* Fix up corner cases, to avoid division by zero or creation of negative
5380 if (total_freq == 0)
5382 if (exit_freq > total_freq)
5383 exit_freq = total_freq;
5386 copy_bbs (region, n_region, region_copy, exits, 2, nexits, orig_loop,
5387 split_edge_bb_loc (exit));
5390 scale_bbs_frequencies_gcov_type (region, n_region,
5391 total_count - exit_count,
5393 scale_bbs_frequencies_gcov_type (region_copy, n_region, exit_count,
5398 scale_bbs_frequencies_int (region, n_region, total_freq - exit_freq,
5400 scale_bbs_frequencies_int (region_copy, n_region, exit_freq, total_freq);
5403 /* Create the switch block, and put the exit condition to it. */
5404 entry_bb = entry->dest;
5405 nentry_bb = get_bb_copy (entry_bb);
5406 if (!last_stmt (entry->src)
5407 || !stmt_ends_bb_p (last_stmt (entry->src)))
5408 switch_bb = entry->src;
5410 switch_bb = split_edge (entry);
5411 set_immediate_dominator (CDI_DOMINATORS, nentry_bb, switch_bb);
5413 gsi = gsi_last_bb (switch_bb);
5414 cond_stmt = last_stmt (exit->src);
5415 gcc_assert (gimple_code (cond_stmt) == GIMPLE_COND);
5416 cond_stmt = gimple_copy (cond_stmt);
5417 gimple_cond_set_lhs (cond_stmt, unshare_expr (gimple_cond_lhs (cond_stmt)));
5418 gimple_cond_set_rhs (cond_stmt, unshare_expr (gimple_cond_rhs (cond_stmt)));
5419 gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT);
5421 sorig = single_succ_edge (switch_bb);
5422 sorig->flags = exits[1]->flags;
5423 snew = make_edge (switch_bb, nentry_bb, exits[0]->flags);
5425 /* Register the new edge from SWITCH_BB in loop exit lists. */
5426 rescan_loop_exit (snew, true, false);
5428 /* Add the PHI node arguments. */
5429 add_phi_args_after_copy (region_copy, n_region, snew);
5431 /* Get rid of now superfluous conditions and associated edges (and phi node
5433 e = redirect_edge_and_branch (exits[0], exits[1]->dest);
5434 PENDING_STMT (e) = NULL;
5435 e = redirect_edge_and_branch (nexits[1], nexits[0]->dest);
5436 PENDING_STMT (e) = NULL;
5438 /* Anything that is outside of the region, but was dominated by something
5439 inside needs to update dominance info. */
5440 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5441 VEC_free (basic_block, heap, doms);
5443 /* Update the SSA web. */
5444 update_ssa (TODO_update_ssa);
5446 if (free_region_copy)
5449 free_original_copy_tables ();
5453 /* Add all the blocks dominated by ENTRY to the array BBS_P. Stop
5454 adding blocks when the dominator traversal reaches EXIT. This
5455 function silently assumes that ENTRY strictly dominates EXIT. */
5458 gather_blocks_in_sese_region (basic_block entry, basic_block exit,
5459 VEC(basic_block,heap) **bbs_p)
5463 for (son = first_dom_son (CDI_DOMINATORS, entry);
5465 son = next_dom_son (CDI_DOMINATORS, son))
5467 VEC_safe_push (basic_block, heap, *bbs_p, son);
5469 gather_blocks_in_sese_region (son, exit, bbs_p);
5473 /* Replaces *TP with a duplicate (belonging to function TO_CONTEXT).
5474 The duplicates are recorded in VARS_MAP. */
5477 replace_by_duplicate_decl (tree *tp, struct pointer_map_t *vars_map,
5480 tree t = *tp, new_t;
5481 struct function *f = DECL_STRUCT_FUNCTION (to_context);
5484 if (DECL_CONTEXT (t) == to_context)
5487 loc = pointer_map_contains (vars_map, t);
5491 loc = pointer_map_insert (vars_map, t);
5495 new_t = copy_var_decl (t, DECL_NAME (t), TREE_TYPE (t));
5496 f->local_decls = tree_cons (NULL_TREE, new_t, f->local_decls);
5500 gcc_assert (TREE_CODE (t) == CONST_DECL);
5501 new_t = copy_node (t);
5503 DECL_CONTEXT (new_t) = to_context;
5508 new_t = (tree) *loc;
5514 /* Creates an ssa name in TO_CONTEXT equivalent to NAME.
5515 VARS_MAP maps old ssa names and var_decls to the new ones. */
5518 replace_ssa_name (tree name, struct pointer_map_t *vars_map,
5522 tree new_name, decl = SSA_NAME_VAR (name);
5524 gcc_assert (is_gimple_reg (name));
5526 loc = pointer_map_contains (vars_map, name);
5530 replace_by_duplicate_decl (&decl, vars_map, to_context);
5532 push_cfun (DECL_STRUCT_FUNCTION (to_context));
5533 if (gimple_in_ssa_p (cfun))
5534 add_referenced_var (decl);
5536 new_name = make_ssa_name (decl, SSA_NAME_DEF_STMT (name));
5537 if (SSA_NAME_IS_DEFAULT_DEF (name))
5538 set_default_def (decl, new_name);
5541 loc = pointer_map_insert (vars_map, name);
5545 new_name = (tree) *loc;
5556 struct pointer_map_t *vars_map;
5557 htab_t new_label_map;
5561 /* Helper for move_block_to_fn. Set TREE_BLOCK in every expression
5562 contained in *TP if it has been ORIG_BLOCK previously and change the
5563 DECL_CONTEXT of every local variable referenced in *TP. */
5566 move_stmt_op (tree *tp, int *walk_subtrees, void *data)
5568 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
5569 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5573 /* We should never have TREE_BLOCK set on non-statements. */
5574 gcc_assert (!TREE_BLOCK (t));
5576 else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
5578 if (TREE_CODE (t) == SSA_NAME)
5579 *tp = replace_ssa_name (t, p->vars_map, p->to_context);
5580 else if (TREE_CODE (t) == LABEL_DECL)
5582 if (p->new_label_map)
5584 struct tree_map in, *out;
5586 out = (struct tree_map *)
5587 htab_find_with_hash (p->new_label_map, &in, DECL_UID (t));
5592 DECL_CONTEXT (t) = p->to_context;
5594 else if (p->remap_decls_p)
5596 /* Replace T with its duplicate. T should no longer appear in the
5597 parent function, so this looks wasteful; however, it may appear
5598 in referenced_vars, and more importantly, as virtual operands of
5599 statements, and in alias lists of other variables. It would be
5600 quite difficult to expunge it from all those places. ??? It might
5601 suffice to do this for addressable variables. */
5602 if ((TREE_CODE (t) == VAR_DECL
5603 && !is_global_var (t))
5604 || TREE_CODE (t) == CONST_DECL)
5605 replace_by_duplicate_decl (tp, p->vars_map, p->to_context);
5608 && gimple_in_ssa_p (cfun))
5610 push_cfun (DECL_STRUCT_FUNCTION (p->to_context));
5611 add_referenced_var (*tp);
5617 else if (TYPE_P (t))
5623 /* Like move_stmt_op, but for gimple statements.
5625 Helper for move_block_to_fn. Set GIMPLE_BLOCK in every expression
5626 contained in the current statement in *GSI_P and change the
5627 DECL_CONTEXT of every local variable referenced in the current
5631 move_stmt_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
5632 struct walk_stmt_info *wi)
5634 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5635 gimple stmt = gsi_stmt (*gsi_p);
5636 tree block = gimple_block (stmt);
5638 if (p->orig_block == NULL_TREE
5639 || block == p->orig_block
5640 || block == NULL_TREE)
5641 gimple_set_block (stmt, p->new_block);
5642 #ifdef ENABLE_CHECKING
5643 else if (block != p->new_block)
5645 while (block && block != p->orig_block)
5646 block = BLOCK_SUPERCONTEXT (block);
5651 if (is_gimple_omp (stmt)
5652 && gimple_code (stmt) != GIMPLE_OMP_RETURN
5653 && gimple_code (stmt) != GIMPLE_OMP_CONTINUE)
5655 /* Do not remap variables inside OMP directives. Variables
5656 referenced in clauses and directive header belong to the
5657 parent function and should not be moved into the child
5659 bool save_remap_decls_p = p->remap_decls_p;
5660 p->remap_decls_p = false;
5661 *handled_ops_p = true;
5663 walk_gimple_seq (gimple_omp_body (stmt), move_stmt_r, move_stmt_op, wi);
5665 p->remap_decls_p = save_remap_decls_p;
5671 /* Marks virtual operands of all statements in basic blocks BBS for
5675 mark_virtual_ops_in_bb (basic_block bb)
5677 gimple_stmt_iterator gsi;
5679 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5680 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5682 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5683 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5686 /* Move basic block BB from function CFUN to function DEST_FN. The
5687 block is moved out of the original linked list and placed after
5688 block AFTER in the new list. Also, the block is removed from the
5689 original array of blocks and placed in DEST_FN's array of blocks.
5690 If UPDATE_EDGE_COUNT_P is true, the edge counts on both CFGs is
5691 updated to reflect the moved edges.
5693 The local variables are remapped to new instances, VARS_MAP is used
5694 to record the mapping. */
5697 move_block_to_fn (struct function *dest_cfun, basic_block bb,
5698 basic_block after, bool update_edge_count_p,
5699 struct move_stmt_d *d, int eh_offset)
5701 struct control_flow_graph *cfg;
5704 gimple_stmt_iterator si;
5705 unsigned old_len, new_len;
5707 /* Remove BB from dominance structures. */
5708 delete_from_dominance_info (CDI_DOMINATORS, bb);
5710 remove_bb_from_loops (bb);
5712 /* Link BB to the new linked list. */
5713 move_block_after (bb, after);
5715 /* Update the edge count in the corresponding flowgraphs. */
5716 if (update_edge_count_p)
5717 FOR_EACH_EDGE (e, ei, bb->succs)
5719 cfun->cfg->x_n_edges--;
5720 dest_cfun->cfg->x_n_edges++;
5723 /* Remove BB from the original basic block array. */
5724 VEC_replace (basic_block, cfun->cfg->x_basic_block_info, bb->index, NULL);
5725 cfun->cfg->x_n_basic_blocks--;
5727 /* Grow DEST_CFUN's basic block array if needed. */
5728 cfg = dest_cfun->cfg;
5729 cfg->x_n_basic_blocks++;
5730 if (bb->index >= cfg->x_last_basic_block)
5731 cfg->x_last_basic_block = bb->index + 1;
5733 old_len = VEC_length (basic_block, cfg->x_basic_block_info);
5734 if ((unsigned) cfg->x_last_basic_block >= old_len)
5736 new_len = cfg->x_last_basic_block + (cfg->x_last_basic_block + 3) / 4;
5737 VEC_safe_grow_cleared (basic_block, gc, cfg->x_basic_block_info,
5741 VEC_replace (basic_block, cfg->x_basic_block_info,
5744 /* Remap the variables in phi nodes. */
5745 for (si = gsi_start_phis (bb); !gsi_end_p (si); )
5747 gimple phi = gsi_stmt (si);
5749 tree op = PHI_RESULT (phi);
5752 if (!is_gimple_reg (op))
5754 /* Remove the phi nodes for virtual operands (alias analysis will be
5755 run for the new function, anyway). */
5756 remove_phi_node (&si, true);
5760 SET_PHI_RESULT (phi,
5761 replace_ssa_name (op, d->vars_map, dest_cfun->decl));
5762 FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
5764 op = USE_FROM_PTR (use);
5765 if (TREE_CODE (op) == SSA_NAME)
5766 SET_USE (use, replace_ssa_name (op, d->vars_map, dest_cfun->decl));
5772 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
5774 gimple stmt = gsi_stmt (si);
5776 struct walk_stmt_info wi;
5778 memset (&wi, 0, sizeof (wi));
5780 walk_gimple_stmt (&si, move_stmt_r, move_stmt_op, &wi);
5782 if (gimple_code (stmt) == GIMPLE_LABEL)
5784 tree label = gimple_label_label (stmt);
5785 int uid = LABEL_DECL_UID (label);
5787 gcc_assert (uid > -1);
5789 old_len = VEC_length (basic_block, cfg->x_label_to_block_map);
5790 if (old_len <= (unsigned) uid)
5792 new_len = 3 * uid / 2 + 1;
5793 VEC_safe_grow_cleared (basic_block, gc,
5794 cfg->x_label_to_block_map, new_len);
5797 VEC_replace (basic_block, cfg->x_label_to_block_map, uid, bb);
5798 VEC_replace (basic_block, cfun->cfg->x_label_to_block_map, uid, NULL);
5800 gcc_assert (DECL_CONTEXT (label) == dest_cfun->decl);
5802 if (uid >= dest_cfun->cfg->last_label_uid)
5803 dest_cfun->cfg->last_label_uid = uid + 1;
5805 else if (gimple_code (stmt) == GIMPLE_RESX && eh_offset != 0)
5806 gimple_resx_set_region (stmt, gimple_resx_region (stmt) + eh_offset);
5808 region = lookup_stmt_eh_region (stmt);
5811 add_stmt_to_eh_region_fn (dest_cfun, stmt, region + eh_offset);
5812 remove_stmt_from_eh_region (stmt);
5813 gimple_duplicate_stmt_histograms (dest_cfun, stmt, cfun, stmt);
5814 gimple_remove_stmt_histograms (cfun, stmt);
5817 /* We cannot leave any operands allocated from the operand caches of
5818 the current function. */
5819 free_stmt_operands (stmt);
5820 push_cfun (dest_cfun);
5825 FOR_EACH_EDGE (e, ei, bb->succs)
5828 tree block = e->goto_block;
5829 if (d->orig_block == NULL_TREE
5830 || block == d->orig_block)
5831 e->goto_block = d->new_block;
5832 #ifdef ENABLE_CHECKING
5833 else if (block != d->new_block)
5835 while (block && block != d->orig_block)
5836 block = BLOCK_SUPERCONTEXT (block);
5843 /* Examine the statements in BB (which is in SRC_CFUN); find and return
5844 the outermost EH region. Use REGION as the incoming base EH region. */
5847 find_outermost_region_in_block (struct function *src_cfun,
5848 basic_block bb, int region)
5850 gimple_stmt_iterator si;
5852 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
5854 gimple stmt = gsi_stmt (si);
5857 if (gimple_code (stmt) == GIMPLE_RESX)
5858 stmt_region = gimple_resx_region (stmt);
5860 stmt_region = lookup_stmt_eh_region_fn (src_cfun, stmt);
5861 if (stmt_region > 0)
5864 region = stmt_region;
5865 else if (stmt_region != region)
5867 region = eh_region_outermost (src_cfun, stmt_region, region);
5868 gcc_assert (region != -1);
5877 new_label_mapper (tree decl, void *data)
5879 htab_t hash = (htab_t) data;
5883 gcc_assert (TREE_CODE (decl) == LABEL_DECL);
5885 m = XNEW (struct tree_map);
5886 m->hash = DECL_UID (decl);
5887 m->base.from = decl;
5888 m->to = create_artificial_label ();
5889 LABEL_DECL_UID (m->to) = LABEL_DECL_UID (decl);
5890 if (LABEL_DECL_UID (m->to) >= cfun->cfg->last_label_uid)
5891 cfun->cfg->last_label_uid = LABEL_DECL_UID (m->to) + 1;
5893 slot = htab_find_slot_with_hash (hash, m, m->hash, INSERT);
5894 gcc_assert (*slot == NULL);
5901 /* Change DECL_CONTEXT of all BLOCK_VARS in block, including
5905 replace_block_vars_by_duplicates (tree block, struct pointer_map_t *vars_map,
5910 for (tp = &BLOCK_VARS (block); *tp; tp = &TREE_CHAIN (*tp))
5913 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != CONST_DECL)
5915 replace_by_duplicate_decl (&t, vars_map, to_context);
5918 if (TREE_CODE (*tp) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (*tp))
5920 SET_DECL_VALUE_EXPR (t, DECL_VALUE_EXPR (*tp));
5921 DECL_HAS_VALUE_EXPR_P (t) = 1;
5923 TREE_CHAIN (t) = TREE_CHAIN (*tp);
5928 for (block = BLOCK_SUBBLOCKS (block); block; block = BLOCK_CHAIN (block))
5929 replace_block_vars_by_duplicates (block, vars_map, to_context);
5932 /* Move a single-entry, single-exit region delimited by ENTRY_BB and
5933 EXIT_BB to function DEST_CFUN. The whole region is replaced by a
5934 single basic block in the original CFG and the new basic block is
5935 returned. DEST_CFUN must not have a CFG yet.
5937 Note that the region need not be a pure SESE region. Blocks inside
5938 the region may contain calls to abort/exit. The only restriction
5939 is that ENTRY_BB should be the only entry point and it must
5942 Change TREE_BLOCK of all statements in ORIG_BLOCK to the new
5943 functions outermost BLOCK, move all subblocks of ORIG_BLOCK
5944 to the new function.
5946 All local variables referenced in the region are assumed to be in
5947 the corresponding BLOCK_VARS and unexpanded variable lists
5948 associated with DEST_CFUN. */
5951 move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb,
5952 basic_block exit_bb, tree orig_block)
5954 VEC(basic_block,heap) *bbs, *dom_bbs;
5955 basic_block dom_entry = get_immediate_dominator (CDI_DOMINATORS, entry_bb);
5956 basic_block after, bb, *entry_pred, *exit_succ, abb;
5957 struct function *saved_cfun = cfun;
5958 int *entry_flag, *exit_flag, eh_offset;
5959 unsigned *entry_prob, *exit_prob;
5960 unsigned i, num_entry_edges, num_exit_edges;
5963 htab_t new_label_map;
5964 struct pointer_map_t *vars_map;
5965 struct loop *loop = entry_bb->loop_father;
5966 struct move_stmt_d d;
5968 /* If ENTRY does not strictly dominate EXIT, this cannot be an SESE
5970 gcc_assert (entry_bb != exit_bb
5972 || dominated_by_p (CDI_DOMINATORS, exit_bb, entry_bb)));
5974 /* Collect all the blocks in the region. Manually add ENTRY_BB
5975 because it won't be added by dfs_enumerate_from. */
5977 VEC_safe_push (basic_block, heap, bbs, entry_bb);
5978 gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs);
5980 /* The blocks that used to be dominated by something in BBS will now be
5981 dominated by the new block. */
5982 dom_bbs = get_dominated_by_region (CDI_DOMINATORS,
5983 VEC_address (basic_block, bbs),
5984 VEC_length (basic_block, bbs));
5986 /* Detach ENTRY_BB and EXIT_BB from CFUN->CFG. We need to remember
5987 the predecessor edges to ENTRY_BB and the successor edges to
5988 EXIT_BB so that we can re-attach them to the new basic block that
5989 will replace the region. */
5990 num_entry_edges = EDGE_COUNT (entry_bb->preds);
5991 entry_pred = (basic_block *) xcalloc (num_entry_edges, sizeof (basic_block));
5992 entry_flag = (int *) xcalloc (num_entry_edges, sizeof (int));
5993 entry_prob = XNEWVEC (unsigned, num_entry_edges);
5995 for (ei = ei_start (entry_bb->preds); (e = ei_safe_edge (ei)) != NULL;)
5997 entry_prob[i] = e->probability;
5998 entry_flag[i] = e->flags;
5999 entry_pred[i++] = e->src;
6005 num_exit_edges = EDGE_COUNT (exit_bb->succs);
6006 exit_succ = (basic_block *) xcalloc (num_exit_edges,
6007 sizeof (basic_block));
6008 exit_flag = (int *) xcalloc (num_exit_edges, sizeof (int));
6009 exit_prob = XNEWVEC (unsigned, num_exit_edges);
6011 for (ei = ei_start (exit_bb->succs); (e = ei_safe_edge (ei)) != NULL;)
6013 exit_prob[i] = e->probability;
6014 exit_flag[i] = e->flags;
6015 exit_succ[i++] = e->dest;
6027 /* Switch context to the child function to initialize DEST_FN's CFG. */
6028 gcc_assert (dest_cfun->cfg == NULL);
6029 push_cfun (dest_cfun);
6031 init_empty_tree_cfg ();
6033 /* Initialize EH information for the new function. */
6035 new_label_map = NULL;
6040 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6041 region = find_outermost_region_in_block (saved_cfun, bb, region);
6043 init_eh_for_function ();
6046 new_label_map = htab_create (17, tree_map_hash, tree_map_eq, free);
6047 eh_offset = duplicate_eh_regions (saved_cfun, new_label_mapper,
6048 new_label_map, region, 0);
6054 /* Move blocks from BBS into DEST_CFUN. */
6055 gcc_assert (VEC_length (basic_block, bbs) >= 2);
6056 after = dest_cfun->cfg->x_entry_block_ptr;
6057 vars_map = pointer_map_create ();
6059 memset (&d, 0, sizeof (d));
6060 d.vars_map = vars_map;
6061 d.from_context = cfun->decl;
6062 d.to_context = dest_cfun->decl;
6063 d.new_label_map = new_label_map;
6064 d.remap_decls_p = true;
6065 d.orig_block = orig_block;
6066 d.new_block = DECL_INITIAL (dest_cfun->decl);
6068 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6070 /* No need to update edge counts on the last block. It has
6071 already been updated earlier when we detached the region from
6072 the original CFG. */
6073 move_block_to_fn (dest_cfun, bb, after, bb != exit_bb, &d, eh_offset);
6077 /* Rewire BLOCK_SUBBLOCKS of orig_block. */
6081 gcc_assert (BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6083 BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6084 = BLOCK_SUBBLOCKS (orig_block);
6085 for (block = BLOCK_SUBBLOCKS (orig_block);
6086 block; block = BLOCK_CHAIN (block))
6087 BLOCK_SUPERCONTEXT (block) = DECL_INITIAL (dest_cfun->decl);
6088 BLOCK_SUBBLOCKS (orig_block) = NULL_TREE;
6091 replace_block_vars_by_duplicates (DECL_INITIAL (dest_cfun->decl),
6092 vars_map, dest_cfun->decl);
6095 htab_delete (new_label_map);
6096 pointer_map_destroy (vars_map);
6098 /* Rewire the entry and exit blocks. The successor to the entry
6099 block turns into the successor of DEST_FN's ENTRY_BLOCK_PTR in
6100 the child function. Similarly, the predecessor of DEST_FN's
6101 EXIT_BLOCK_PTR turns into the predecessor of EXIT_BLOCK_PTR. We
6102 need to switch CFUN between DEST_CFUN and SAVED_CFUN so that the
6103 various CFG manipulation function get to the right CFG.
6105 FIXME, this is silly. The CFG ought to become a parameter to
6107 push_cfun (dest_cfun);
6108 make_edge (ENTRY_BLOCK_PTR, entry_bb, EDGE_FALLTHRU);
6110 make_edge (exit_bb, EXIT_BLOCK_PTR, 0);
6113 /* Back in the original function, the SESE region has disappeared,
6114 create a new basic block in its place. */
6115 bb = create_empty_bb (entry_pred[0]);
6117 add_bb_to_loop (bb, loop);
6118 for (i = 0; i < num_entry_edges; i++)
6120 e = make_edge (entry_pred[i], bb, entry_flag[i]);
6121 e->probability = entry_prob[i];
6124 for (i = 0; i < num_exit_edges; i++)
6126 e = make_edge (bb, exit_succ[i], exit_flag[i]);
6127 e->probability = exit_prob[i];
6130 set_immediate_dominator (CDI_DOMINATORS, bb, dom_entry);
6131 for (i = 0; VEC_iterate (basic_block, dom_bbs, i, abb); i++)
6132 set_immediate_dominator (CDI_DOMINATORS, abb, bb);
6133 VEC_free (basic_block, heap, dom_bbs);
6144 VEC_free (basic_block, heap, bbs);
6150 /* Dump FUNCTION_DECL FN to file FILE using FLAGS (see TDF_* in tree-pass.h)
6154 dump_function_to_file (tree fn, FILE *file, int flags)
6156 tree arg, vars, var;
6157 struct function *dsf;
6158 bool ignore_topmost_bind = false, any_var = false;
6162 fprintf (file, "%s (", lang_hooks.decl_printable_name (fn, 2));
6164 arg = DECL_ARGUMENTS (fn);
6167 print_generic_expr (file, TREE_TYPE (arg), dump_flags);
6168 fprintf (file, " ");
6169 print_generic_expr (file, arg, dump_flags);
6170 if (flags & TDF_VERBOSE)
6171 print_node (file, "", arg, 4);
6172 if (TREE_CHAIN (arg))
6173 fprintf (file, ", ");
6174 arg = TREE_CHAIN (arg);
6176 fprintf (file, ")\n");
6178 if (flags & TDF_VERBOSE)
6179 print_node (file, "", fn, 2);
6181 dsf = DECL_STRUCT_FUNCTION (fn);
6182 if (dsf && (flags & TDF_DETAILS))
6183 dump_eh_tree (file, dsf);
6185 if (flags & TDF_RAW && !gimple_has_body_p (fn))
6187 dump_node (fn, TDF_SLIM | flags, file);
6191 /* Switch CFUN to point to FN. */
6192 push_cfun (DECL_STRUCT_FUNCTION (fn));
6194 /* When GIMPLE is lowered, the variables are no longer available in
6195 BIND_EXPRs, so display them separately. */
6196 if (cfun && cfun->decl == fn && cfun->local_decls)
6198 ignore_topmost_bind = true;
6200 fprintf (file, "{\n");
6201 for (vars = cfun->local_decls; vars; vars = TREE_CHAIN (vars))
6203 var = TREE_VALUE (vars);
6205 print_generic_decl (file, var, flags);
6206 if (flags & TDF_VERBOSE)
6207 print_node (file, "", var, 4);
6208 fprintf (file, "\n");
6214 if (cfun && cfun->decl == fn && cfun->cfg && basic_block_info)
6216 /* If the CFG has been built, emit a CFG-based dump. */
6217 check_bb_profile (ENTRY_BLOCK_PTR, file);
6218 if (!ignore_topmost_bind)
6219 fprintf (file, "{\n");
6221 if (any_var && n_basic_blocks)
6222 fprintf (file, "\n");
6225 gimple_dump_bb (bb, file, 2, flags);
6227 fprintf (file, "}\n");
6228 check_bb_profile (EXIT_BLOCK_PTR, file);
6230 else if (DECL_SAVED_TREE (fn) == NULL)
6232 /* The function is now in GIMPLE form but the CFG has not been
6233 built yet. Emit the single sequence of GIMPLE statements
6234 that make up its body. */
6235 gimple_seq body = gimple_body (fn);
6237 if (gimple_seq_first_stmt (body)
6238 && gimple_seq_first_stmt (body) == gimple_seq_last_stmt (body)
6239 && gimple_code (gimple_seq_first_stmt (body)) == GIMPLE_BIND)
6240 print_gimple_seq (file, body, 0, flags);
6243 if (!ignore_topmost_bind)
6244 fprintf (file, "{\n");
6247 fprintf (file, "\n");
6249 print_gimple_seq (file, body, 2, flags);
6250 fprintf (file, "}\n");
6257 /* Make a tree based dump. */
6258 chain = DECL_SAVED_TREE (fn);
6260 if (chain && TREE_CODE (chain) == BIND_EXPR)
6262 if (ignore_topmost_bind)
6264 chain = BIND_EXPR_BODY (chain);
6272 if (!ignore_topmost_bind)
6273 fprintf (file, "{\n");
6278 fprintf (file, "\n");
6280 print_generic_stmt_indented (file, chain, flags, indent);
6281 if (ignore_topmost_bind)
6282 fprintf (file, "}\n");
6285 fprintf (file, "\n\n");
6292 /* Dump FUNCTION_DECL FN to stderr using FLAGS (see TDF_* in tree.h) */
6295 debug_function (tree fn, int flags)
6297 dump_function_to_file (fn, stderr, flags);
6301 /* Print on FILE the indexes for the predecessors of basic_block BB. */
6304 print_pred_bbs (FILE *file, basic_block bb)
6309 FOR_EACH_EDGE (e, ei, bb->preds)
6310 fprintf (file, "bb_%d ", e->src->index);
6314 /* Print on FILE the indexes for the successors of basic_block BB. */
6317 print_succ_bbs (FILE *file, basic_block bb)
6322 FOR_EACH_EDGE (e, ei, bb->succs)
6323 fprintf (file, "bb_%d ", e->dest->index);
6326 /* Print to FILE the basic block BB following the VERBOSITY level. */
6329 print_loops_bb (FILE *file, basic_block bb, int indent, int verbosity)
6331 char *s_indent = (char *) alloca ((size_t) indent + 1);
6332 memset ((void *) s_indent, ' ', (size_t) indent);
6333 s_indent[indent] = '\0';
6335 /* Print basic_block's header. */
6338 fprintf (file, "%s bb_%d (preds = {", s_indent, bb->index);
6339 print_pred_bbs (file, bb);
6340 fprintf (file, "}, succs = {");
6341 print_succ_bbs (file, bb);
6342 fprintf (file, "})\n");
6345 /* Print basic_block's body. */
6348 fprintf (file, "%s {\n", s_indent);
6349 gimple_dump_bb (bb, file, indent + 4, TDF_VOPS|TDF_MEMSYMS);
6350 fprintf (file, "%s }\n", s_indent);
6354 static void print_loop_and_siblings (FILE *, struct loop *, int, int);
6356 /* Pretty print LOOP on FILE, indented INDENT spaces. Following
6357 VERBOSITY level this outputs the contents of the loop, or just its
6361 print_loop (FILE *file, struct loop *loop, int indent, int verbosity)
6369 s_indent = (char *) alloca ((size_t) indent + 1);
6370 memset ((void *) s_indent, ' ', (size_t) indent);
6371 s_indent[indent] = '\0';
6373 /* Print loop's header. */
6374 fprintf (file, "%sloop_%d (header = %d, latch = %d", s_indent,
6375 loop->num, loop->header->index, loop->latch->index);
6376 fprintf (file, ", niter = ");
6377 print_generic_expr (file, loop->nb_iterations, 0);
6379 if (loop->any_upper_bound)
6381 fprintf (file, ", upper_bound = ");
6382 dump_double_int (file, loop->nb_iterations_upper_bound, true);
6385 if (loop->any_estimate)
6387 fprintf (file, ", estimate = ");
6388 dump_double_int (file, loop->nb_iterations_estimate, true);
6390 fprintf (file, ")\n");
6392 /* Print loop's body. */
6395 fprintf (file, "%s{\n", s_indent);
6397 if (bb->loop_father == loop)
6398 print_loops_bb (file, bb, indent, verbosity);
6400 print_loop_and_siblings (file, loop->inner, indent + 2, verbosity);
6401 fprintf (file, "%s}\n", s_indent);
6405 /* Print the LOOP and its sibling loops on FILE, indented INDENT
6406 spaces. Following VERBOSITY level this outputs the contents of the
6407 loop, or just its structure. */
6410 print_loop_and_siblings (FILE *file, struct loop *loop, int indent, int verbosity)
6415 print_loop (file, loop, indent, verbosity);
6416 print_loop_and_siblings (file, loop->next, indent, verbosity);
6419 /* Follow a CFG edge from the entry point of the program, and on entry
6420 of a loop, pretty print the loop structure on FILE. */
6423 print_loops (FILE *file, int verbosity)
6427 bb = ENTRY_BLOCK_PTR;
6428 if (bb && bb->loop_father)
6429 print_loop_and_siblings (file, bb->loop_father, 0, verbosity);
6433 /* Debugging loops structure at tree level, at some VERBOSITY level. */
6436 debug_loops (int verbosity)
6438 print_loops (stderr, verbosity);
6441 /* Print on stderr the code of LOOP, at some VERBOSITY level. */
6444 debug_loop (struct loop *loop, int verbosity)
6446 print_loop (stderr, loop, 0, verbosity);
6449 /* Print on stderr the code of loop number NUM, at some VERBOSITY
6453 debug_loop_num (unsigned num, int verbosity)
6455 debug_loop (get_loop (num), verbosity);
6458 /* Return true if BB ends with a call, possibly followed by some
6459 instructions that must stay with the call. Return false,
6463 gimple_block_ends_with_call_p (basic_block bb)
6465 gimple_stmt_iterator gsi = gsi_last_bb (bb);
6466 return is_gimple_call (gsi_stmt (gsi));
6470 /* Return true if BB ends with a conditional branch. Return false,
6474 gimple_block_ends_with_condjump_p (const_basic_block bb)
6476 gimple stmt = last_stmt (CONST_CAST_BB (bb));
6477 return (stmt && gimple_code (stmt) == GIMPLE_COND);
6481 /* Return true if we need to add fake edge to exit at statement T.
6482 Helper function for gimple_flow_call_edges_add. */
6485 need_fake_edge_p (gimple t)
6487 tree fndecl = NULL_TREE;
6490 /* NORETURN and LONGJMP calls already have an edge to exit.
6491 CONST and PURE calls do not need one.
6492 We don't currently check for CONST and PURE here, although
6493 it would be a good idea, because those attributes are
6494 figured out from the RTL in mark_constant_function, and
6495 the counter incrementation code from -fprofile-arcs
6496 leads to different results from -fbranch-probabilities. */
6497 if (is_gimple_call (t))
6499 fndecl = gimple_call_fndecl (t);
6500 call_flags = gimple_call_flags (t);
6503 if (is_gimple_call (t)
6505 && DECL_BUILT_IN (fndecl)
6506 && (call_flags & ECF_NOTHROW)
6507 && !(call_flags & ECF_RETURNS_TWICE)
6508 /* fork() doesn't really return twice, but the effect of
6509 wrapping it in __gcov_fork() which calls __gcov_flush()
6510 and clears the counters before forking has the same
6511 effect as returning twice. Force a fake edge. */
6512 && !(DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6513 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_FORK))
6516 if (is_gimple_call (t)
6517 && !(call_flags & ECF_NORETURN))
6520 if (gimple_code (t) == GIMPLE_ASM
6521 && (gimple_asm_volatile_p (t) || gimple_asm_input_p (t)))
6528 /* Add fake edges to the function exit for any non constant and non
6529 noreturn calls, volatile inline assembly in the bitmap of blocks
6530 specified by BLOCKS or to the whole CFG if BLOCKS is zero. Return
6531 the number of blocks that were split.
6533 The goal is to expose cases in which entering a basic block does
6534 not imply that all subsequent instructions must be executed. */
6537 gimple_flow_call_edges_add (sbitmap blocks)
6540 int blocks_split = 0;
6541 int last_bb = last_basic_block;
6542 bool check_last_block = false;
6544 if (n_basic_blocks == NUM_FIXED_BLOCKS)
6548 check_last_block = true;
6550 check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index);
6552 /* In the last basic block, before epilogue generation, there will be
6553 a fallthru edge to EXIT. Special care is required if the last insn
6554 of the last basic block is a call because make_edge folds duplicate
6555 edges, which would result in the fallthru edge also being marked
6556 fake, which would result in the fallthru edge being removed by
6557 remove_fake_edges, which would result in an invalid CFG.
6559 Moreover, we can't elide the outgoing fake edge, since the block
6560 profiler needs to take this into account in order to solve the minimal
6561 spanning tree in the case that the call doesn't return.
6563 Handle this by adding a dummy instruction in a new last basic block. */
6564 if (check_last_block)
6566 basic_block bb = EXIT_BLOCK_PTR->prev_bb;
6567 gimple_stmt_iterator gsi = gsi_last_bb (bb);
6570 if (!gsi_end_p (gsi))
6573 if (t && need_fake_edge_p (t))
6577 e = find_edge (bb, EXIT_BLOCK_PTR);
6580 gsi_insert_on_edge (e, gimple_build_nop ());
6581 gsi_commit_edge_inserts ();
6586 /* Now add fake edges to the function exit for any non constant
6587 calls since there is no way that we can determine if they will
6589 for (i = 0; i < last_bb; i++)
6591 basic_block bb = BASIC_BLOCK (i);
6592 gimple_stmt_iterator gsi;
6593 gimple stmt, last_stmt;
6598 if (blocks && !TEST_BIT (blocks, i))
6601 gsi = gsi_last_bb (bb);
6602 if (!gsi_end_p (gsi))
6604 last_stmt = gsi_stmt (gsi);
6607 stmt = gsi_stmt (gsi);
6608 if (need_fake_edge_p (stmt))
6612 /* The handling above of the final block before the
6613 epilogue should be enough to verify that there is
6614 no edge to the exit block in CFG already.
6615 Calling make_edge in such case would cause us to
6616 mark that edge as fake and remove it later. */
6617 #ifdef ENABLE_CHECKING
6618 if (stmt == last_stmt)
6620 e = find_edge (bb, EXIT_BLOCK_PTR);
6621 gcc_assert (e == NULL);
6625 /* Note that the following may create a new basic block
6626 and renumber the existing basic blocks. */
6627 if (stmt != last_stmt)
6629 e = split_block (bb, stmt);
6633 make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE);
6637 while (!gsi_end_p (gsi));
6642 verify_flow_info ();
6644 return blocks_split;
6647 /* Purge dead abnormal call edges from basic block BB. */
6650 gimple_purge_dead_abnormal_call_edges (basic_block bb)
6652 bool changed = gimple_purge_dead_eh_edges (bb);
6654 if (cfun->has_nonlocal_label)
6656 gimple stmt = last_stmt (bb);
6660 if (!(stmt && stmt_can_make_abnormal_goto (stmt)))
6661 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6663 if (e->flags & EDGE_ABNORMAL)
6672 /* See gimple_purge_dead_eh_edges below. */
6674 free_dominance_info (CDI_DOMINATORS);
6680 /* Stores all basic blocks dominated by BB to DOM_BBS. */
6683 get_all_dominated_blocks (basic_block bb, VEC (basic_block, heap) **dom_bbs)
6687 VEC_safe_push (basic_block, heap, *dom_bbs, bb);
6688 for (son = first_dom_son (CDI_DOMINATORS, bb);
6690 son = next_dom_son (CDI_DOMINATORS, son))
6691 get_all_dominated_blocks (son, dom_bbs);
6694 /* Removes edge E and all the blocks dominated by it, and updates dominance
6695 information. The IL in E->src needs to be updated separately.
6696 If dominance info is not available, only the edge E is removed.*/
6699 remove_edge_and_dominated_blocks (edge e)
6701 VEC (basic_block, heap) *bbs_to_remove = NULL;
6702 VEC (basic_block, heap) *bbs_to_fix_dom = NULL;
6706 bool none_removed = false;
6708 basic_block bb, dbb;
6711 if (!dom_info_available_p (CDI_DOMINATORS))
6717 /* No updating is needed for edges to exit. */
6718 if (e->dest == EXIT_BLOCK_PTR)
6720 if (cfgcleanup_altered_bbs)
6721 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6726 /* First, we find the basic blocks to remove. If E->dest has a predecessor
6727 that is not dominated by E->dest, then this set is empty. Otherwise,
6728 all the basic blocks dominated by E->dest are removed.
6730 Also, to DF_IDOM we store the immediate dominators of the blocks in
6731 the dominance frontier of E (i.e., of the successors of the
6732 removed blocks, if there are any, and of E->dest otherwise). */
6733 FOR_EACH_EDGE (f, ei, e->dest->preds)
6738 if (!dominated_by_p (CDI_DOMINATORS, f->src, e->dest))
6740 none_removed = true;
6745 df = BITMAP_ALLOC (NULL);
6746 df_idom = BITMAP_ALLOC (NULL);
6749 bitmap_set_bit (df_idom,
6750 get_immediate_dominator (CDI_DOMINATORS, e->dest)->index);
6753 get_all_dominated_blocks (e->dest, &bbs_to_remove);
6754 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6756 FOR_EACH_EDGE (f, ei, bb->succs)
6758 if (f->dest != EXIT_BLOCK_PTR)
6759 bitmap_set_bit (df, f->dest->index);
6762 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6763 bitmap_clear_bit (df, bb->index);
6765 EXECUTE_IF_SET_IN_BITMAP (df, 0, i, bi)
6767 bb = BASIC_BLOCK (i);
6768 bitmap_set_bit (df_idom,
6769 get_immediate_dominator (CDI_DOMINATORS, bb)->index);
6773 if (cfgcleanup_altered_bbs)
6775 /* Record the set of the altered basic blocks. */
6776 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6777 bitmap_ior_into (cfgcleanup_altered_bbs, df);
6780 /* Remove E and the cancelled blocks. */
6785 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6786 delete_basic_block (bb);
6789 /* Update the dominance information. The immediate dominator may change only
6790 for blocks whose immediate dominator belongs to DF_IDOM:
6792 Suppose that idom(X) = Y before removal of E and idom(X) != Y after the
6793 removal. Let Z the arbitrary block such that idom(Z) = Y and
6794 Z dominates X after the removal. Before removal, there exists a path P
6795 from Y to X that avoids Z. Let F be the last edge on P that is
6796 removed, and let W = F->dest. Before removal, idom(W) = Y (since Y
6797 dominates W, and because of P, Z does not dominate W), and W belongs to
6798 the dominance frontier of E. Therefore, Y belongs to DF_IDOM. */
6799 EXECUTE_IF_SET_IN_BITMAP (df_idom, 0, i, bi)
6801 bb = BASIC_BLOCK (i);
6802 for (dbb = first_dom_son (CDI_DOMINATORS, bb);
6804 dbb = next_dom_son (CDI_DOMINATORS, dbb))
6805 VEC_safe_push (basic_block, heap, bbs_to_fix_dom, dbb);
6808 iterate_fix_dominators (CDI_DOMINATORS, bbs_to_fix_dom, true);
6811 BITMAP_FREE (df_idom);
6812 VEC_free (basic_block, heap, bbs_to_remove);
6813 VEC_free (basic_block, heap, bbs_to_fix_dom);
6816 /* Purge dead EH edges from basic block BB. */
6819 gimple_purge_dead_eh_edges (basic_block bb)
6821 bool changed = false;
6824 gimple stmt = last_stmt (bb);
6826 if (stmt && stmt_can_throw_internal (stmt))
6829 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6831 if (e->flags & EDGE_EH)
6833 remove_edge_and_dominated_blocks (e);
6844 gimple_purge_all_dead_eh_edges (const_bitmap blocks)
6846 bool changed = false;
6850 EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
6852 basic_block bb = BASIC_BLOCK (i);
6854 /* Earlier gimple_purge_dead_eh_edges could have removed
6855 this basic block already. */
6856 gcc_assert (bb || changed);
6858 changed |= gimple_purge_dead_eh_edges (bb);
6864 /* This function is called whenever a new edge is created or
6868 gimple_execute_on_growing_pred (edge e)
6870 basic_block bb = e->dest;
6873 reserve_phi_args_for_new_edge (bb);
6876 /* This function is called immediately before edge E is removed from
6877 the edge vector E->dest->preds. */
6880 gimple_execute_on_shrinking_pred (edge e)
6882 if (phi_nodes (e->dest))
6883 remove_phi_args (e);
6886 /*---------------------------------------------------------------------------
6887 Helper functions for Loop versioning
6888 ---------------------------------------------------------------------------*/
6890 /* Adjust phi nodes for 'first' basic block. 'second' basic block is a copy
6891 of 'first'. Both of them are dominated by 'new_head' basic block. When
6892 'new_head' was created by 'second's incoming edge it received phi arguments
6893 on the edge by split_edge(). Later, additional edge 'e' was created to
6894 connect 'new_head' and 'first'. Now this routine adds phi args on this
6895 additional edge 'e' that new_head to second edge received as part of edge
6899 gimple_lv_adjust_loop_header_phi (basic_block first, basic_block second,
6900 basic_block new_head, edge e)
6903 gimple_stmt_iterator psi1, psi2;
6905 edge e2 = find_edge (new_head, second);
6907 /* Because NEW_HEAD has been created by splitting SECOND's incoming
6908 edge, we should always have an edge from NEW_HEAD to SECOND. */
6909 gcc_assert (e2 != NULL);
6911 /* Browse all 'second' basic block phi nodes and add phi args to
6912 edge 'e' for 'first' head. PHI args are always in correct order. */
6914 for (psi2 = gsi_start_phis (second),
6915 psi1 = gsi_start_phis (first);
6916 !gsi_end_p (psi2) && !gsi_end_p (psi1);
6917 gsi_next (&psi2), gsi_next (&psi1))
6919 phi1 = gsi_stmt (psi1);
6920 phi2 = gsi_stmt (psi2);
6921 def = PHI_ARG_DEF (phi2, e2->dest_idx);
6922 add_phi_arg (phi1, def, e);
6927 /* Adds a if else statement to COND_BB with condition COND_EXPR.
6928 SECOND_HEAD is the destination of the THEN and FIRST_HEAD is
6929 the destination of the ELSE part. */
6932 gimple_lv_add_condition_to_bb (basic_block first_head ATTRIBUTE_UNUSED,
6933 basic_block second_head ATTRIBUTE_UNUSED,
6934 basic_block cond_bb, void *cond_e)
6936 gimple_stmt_iterator gsi;
6937 gimple new_cond_expr;
6938 tree cond_expr = (tree) cond_e;
6941 /* Build new conditional expr */
6942 new_cond_expr = gimple_build_cond_from_tree (cond_expr,
6943 NULL_TREE, NULL_TREE);
6945 /* Add new cond in cond_bb. */
6946 gsi = gsi_last_bb (cond_bb);
6947 gsi_insert_after (&gsi, new_cond_expr, GSI_NEW_STMT);
6949 /* Adjust edges appropriately to connect new head with first head
6950 as well as second head. */
6951 e0 = single_succ_edge (cond_bb);
6952 e0->flags &= ~EDGE_FALLTHRU;
6953 e0->flags |= EDGE_FALSE_VALUE;
6956 struct cfg_hooks gimple_cfg_hooks = {
6958 gimple_verify_flow_info,
6959 gimple_dump_bb, /* dump_bb */
6960 create_bb, /* create_basic_block */
6961 gimple_redirect_edge_and_branch, /* redirect_edge_and_branch */
6962 gimple_redirect_edge_and_branch_force, /* redirect_edge_and_branch_force */
6963 gimple_can_remove_branch_p, /* can_remove_branch_p */
6964 remove_bb, /* delete_basic_block */
6965 gimple_split_block, /* split_block */
6966 gimple_move_block_after, /* move_block_after */
6967 gimple_can_merge_blocks_p, /* can_merge_blocks_p */
6968 gimple_merge_blocks, /* merge_blocks */
6969 gimple_predict_edge, /* predict_edge */
6970 gimple_predicted_by_p, /* predicted_by_p */
6971 gimple_can_duplicate_bb_p, /* can_duplicate_block_p */
6972 gimple_duplicate_bb, /* duplicate_block */
6973 gimple_split_edge, /* split_edge */
6974 gimple_make_forwarder_block, /* make_forward_block */
6975 NULL, /* tidy_fallthru_edge */
6976 gimple_block_ends_with_call_p,/* block_ends_with_call_p */
6977 gimple_block_ends_with_condjump_p, /* block_ends_with_condjump_p */
6978 gimple_flow_call_edges_add, /* flow_call_edges_add */
6979 gimple_execute_on_growing_pred, /* execute_on_growing_pred */
6980 gimple_execute_on_shrinking_pred, /* execute_on_shrinking_pred */
6981 gimple_duplicate_loop_to_header_edge, /* duplicate loop for trees */
6982 gimple_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
6983 gimple_lv_adjust_loop_header_phi, /* lv_adjust_loop_header_phi*/
6984 extract_true_false_edges_from_block, /* extract_cond_bb_edges */
6985 flush_pending_stmts /* flush_pending_stmts */
6989 /* Split all critical edges. */
6992 split_critical_edges (void)
6998 /* split_edge can redirect edges out of SWITCH_EXPRs, which can get
6999 expensive. So we want to enable recording of edge to CASE_LABEL_EXPR
7000 mappings around the calls to split_edge. */
7001 start_recording_case_labels ();
7004 FOR_EACH_EDGE (e, ei, bb->succs)
7005 if (EDGE_CRITICAL_P (e) && !(e->flags & EDGE_ABNORMAL))
7010 end_recording_case_labels ();
7014 struct gimple_opt_pass pass_split_crit_edges =
7018 "crited", /* name */
7020 split_critical_edges, /* execute */
7023 0, /* static_pass_number */
7024 TV_TREE_SPLIT_EDGES, /* tv_id */
7025 PROP_cfg, /* properties required */
7026 PROP_no_crit_edges, /* properties_provided */
7027 0, /* properties_destroyed */
7028 0, /* todo_flags_start */
7029 TODO_dump_func /* todo_flags_finish */
7034 /* Build a ternary operation and gimplify it. Emit code before GSI.
7035 Return the gimple_val holding the result. */
7038 gimplify_build3 (gimple_stmt_iterator *gsi, enum tree_code code,
7039 tree type, tree a, tree b, tree c)
7043 ret = fold_build3 (code, type, a, b, c);
7046 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7050 /* Build a binary operation and gimplify it. Emit code before GSI.
7051 Return the gimple_val holding the result. */
7054 gimplify_build2 (gimple_stmt_iterator *gsi, enum tree_code code,
7055 tree type, tree a, tree b)
7059 ret = fold_build2 (code, type, a, b);
7062 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7066 /* Build a unary operation and gimplify it. Emit code before GSI.
7067 Return the gimple_val holding the result. */
7070 gimplify_build1 (gimple_stmt_iterator *gsi, enum tree_code code, tree type,
7075 ret = fold_build1 (code, type, a);
7078 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7084 /* Emit return warnings. */
7087 execute_warn_function_return (void)
7089 source_location location;
7094 /* If we have a path to EXIT, then we do return. */
7095 if (TREE_THIS_VOLATILE (cfun->decl)
7096 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0)
7098 location = UNKNOWN_LOCATION;
7099 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7101 last = last_stmt (e->src);
7102 if (gimple_code (last) == GIMPLE_RETURN
7103 && (location = gimple_location (last)) != UNKNOWN_LOCATION)
7106 if (location == UNKNOWN_LOCATION)
7107 location = cfun->function_end_locus;
7108 warning (0, "%H%<noreturn%> function does return", &location);
7111 /* If we see "return;" in some basic block, then we do reach the end
7112 without returning a value. */
7113 else if (warn_return_type
7114 && !TREE_NO_WARNING (cfun->decl)
7115 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0
7116 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (cfun->decl))))
7118 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7120 gimple last = last_stmt (e->src);
7121 if (gimple_code (last) == GIMPLE_RETURN
7122 && gimple_return_retval (last) == NULL
7123 && !gimple_no_warning_p (last))
7125 location = gimple_location (last);
7126 if (location == UNKNOWN_LOCATION)
7127 location = cfun->function_end_locus;
7128 warning_at (location, OPT_Wreturn_type, "control reaches end of non-void function");
7129 TREE_NO_WARNING (cfun->decl) = 1;
7138 /* Given a basic block B which ends with a conditional and has
7139 precisely two successors, determine which of the edges is taken if
7140 the conditional is true and which is taken if the conditional is
7141 false. Set TRUE_EDGE and FALSE_EDGE appropriately. */
7144 extract_true_false_edges_from_block (basic_block b,
7148 edge e = EDGE_SUCC (b, 0);
7150 if (e->flags & EDGE_TRUE_VALUE)
7153 *false_edge = EDGE_SUCC (b, 1);
7158 *true_edge = EDGE_SUCC (b, 1);
7162 struct gimple_opt_pass pass_warn_function_return =
7168 execute_warn_function_return, /* execute */
7171 0, /* static_pass_number */
7172 TV_NONE, /* tv_id */
7173 PROP_cfg, /* properties_required */
7174 0, /* properties_provided */
7175 0, /* properties_destroyed */
7176 0, /* todo_flags_start */
7177 0 /* todo_flags_finish */
7181 /* Emit noreturn warnings. */
7184 execute_warn_function_noreturn (void)
7186 if (warn_missing_noreturn
7187 && !TREE_THIS_VOLATILE (cfun->decl)
7188 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0
7189 && !lang_hooks.missing_noreturn_ok_p (cfun->decl))
7190 warning (OPT_Wmissing_noreturn, "%Jfunction might be possible candidate "
7191 "for attribute %<noreturn%>",
7196 struct gimple_opt_pass pass_warn_function_noreturn =
7202 execute_warn_function_noreturn, /* execute */
7205 0, /* static_pass_number */
7206 TV_NONE, /* tv_id */
7207 PROP_cfg, /* properties_required */
7208 0, /* properties_provided */
7209 0, /* properties_destroyed */
7210 0, /* todo_flags_start */
7211 0 /* todo_flags_finish */