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 /* Hash table to store last discriminator assigned for each locus. */
86 struct locus_discrim_map
91 static htab_t discriminator_per_locus;
93 /* Basic blocks and flowgraphs. */
94 static void make_blocks (gimple_seq);
95 static void factor_computed_gotos (void);
98 static void make_edges (void);
99 static void make_cond_expr_edges (basic_block);
100 static void make_gimple_switch_edges (basic_block);
101 static void make_goto_expr_edges (basic_block);
102 static unsigned int locus_map_hash (const void *);
103 static int locus_map_eq (const void *, const void *);
104 static void assign_discriminator (location_t, basic_block);
105 static edge gimple_redirect_edge_and_branch (edge, basic_block);
106 static edge gimple_try_redirect_by_replacing_jump (edge, basic_block);
107 static unsigned int split_critical_edges (void);
109 /* Various helpers. */
110 static inline bool stmt_starts_bb_p (gimple, gimple);
111 static int gimple_verify_flow_info (void);
112 static void gimple_make_forwarder_block (edge);
113 static void gimple_cfg2vcg (FILE *);
114 static gimple first_non_label_stmt (basic_block);
116 /* Flowgraph optimization and cleanup. */
117 static void gimple_merge_blocks (basic_block, basic_block);
118 static bool gimple_can_merge_blocks_p (basic_block, basic_block);
119 static void remove_bb (basic_block);
120 static edge find_taken_edge_computed_goto (basic_block, tree);
121 static edge find_taken_edge_cond_expr (basic_block, tree);
122 static edge find_taken_edge_switch_expr (basic_block, tree);
123 static tree find_case_label_for_value (gimple, tree);
126 init_empty_tree_cfg_for_function (struct function *fn)
128 /* Initialize the basic block array. */
130 profile_status_for_function (fn) = PROFILE_ABSENT;
131 n_basic_blocks_for_function (fn) = NUM_FIXED_BLOCKS;
132 last_basic_block_for_function (fn) = NUM_FIXED_BLOCKS;
133 basic_block_info_for_function (fn)
134 = VEC_alloc (basic_block, gc, initial_cfg_capacity);
135 VEC_safe_grow_cleared (basic_block, gc,
136 basic_block_info_for_function (fn),
137 initial_cfg_capacity);
139 /* Build a mapping of labels to their associated blocks. */
140 label_to_block_map_for_function (fn)
141 = VEC_alloc (basic_block, gc, initial_cfg_capacity);
142 VEC_safe_grow_cleared (basic_block, gc,
143 label_to_block_map_for_function (fn),
144 initial_cfg_capacity);
146 SET_BASIC_BLOCK_FOR_FUNCTION (fn, ENTRY_BLOCK,
147 ENTRY_BLOCK_PTR_FOR_FUNCTION (fn));
148 SET_BASIC_BLOCK_FOR_FUNCTION (fn, EXIT_BLOCK,
149 EXIT_BLOCK_PTR_FOR_FUNCTION (fn));
151 ENTRY_BLOCK_PTR_FOR_FUNCTION (fn)->next_bb
152 = EXIT_BLOCK_PTR_FOR_FUNCTION (fn);
153 EXIT_BLOCK_PTR_FOR_FUNCTION (fn)->prev_bb
154 = ENTRY_BLOCK_PTR_FOR_FUNCTION (fn);
158 init_empty_tree_cfg (void)
160 init_empty_tree_cfg_for_function (cfun);
163 /*---------------------------------------------------------------------------
165 ---------------------------------------------------------------------------*/
167 /* Entry point to the CFG builder for trees. SEQ is the sequence of
168 statements to be added to the flowgraph. */
171 build_gimple_cfg (gimple_seq seq)
173 /* Register specific gimple functions. */
174 gimple_register_cfg_hooks ();
176 memset ((void *) &cfg_stats, 0, sizeof (cfg_stats));
178 init_empty_tree_cfg ();
180 found_computed_goto = 0;
183 /* Computed gotos are hell to deal with, especially if there are
184 lots of them with a large number of destinations. So we factor
185 them to a common computed goto location before we build the
186 edge list. After we convert back to normal form, we will un-factor
187 the computed gotos since factoring introduces an unwanted jump. */
188 if (found_computed_goto)
189 factor_computed_gotos ();
191 /* Make sure there is always at least one block, even if it's empty. */
192 if (n_basic_blocks == NUM_FIXED_BLOCKS)
193 create_empty_bb (ENTRY_BLOCK_PTR);
195 /* Adjust the size of the array. */
196 if (VEC_length (basic_block, basic_block_info) < (size_t) n_basic_blocks)
197 VEC_safe_grow_cleared (basic_block, gc, basic_block_info, n_basic_blocks);
199 /* To speed up statement iterator walks, we first purge dead labels. */
200 cleanup_dead_labels ();
202 /* Group case nodes to reduce the number of edges.
203 We do this after cleaning up dead labels because otherwise we miss
204 a lot of obvious case merging opportunities. */
205 group_case_labels ();
207 /* Create the edges of the flowgraph. */
208 discriminator_per_locus = htab_create (13, locus_map_hash, locus_map_eq,
211 cleanup_dead_labels ();
212 htab_delete (discriminator_per_locus);
214 /* Debugging dumps. */
216 /* Write the flowgraph to a VCG file. */
218 int local_dump_flags;
219 FILE *vcg_file = dump_begin (TDI_vcg, &local_dump_flags);
222 gimple_cfg2vcg (vcg_file);
223 dump_end (TDI_vcg, vcg_file);
227 #ifdef ENABLE_CHECKING
233 execute_build_cfg (void)
235 gimple_seq body = gimple_body (current_function_decl);
237 build_gimple_cfg (body);
238 gimple_set_body (current_function_decl, NULL);
239 if (dump_file && (dump_flags & TDF_DETAILS))
241 fprintf (dump_file, "Scope blocks:\n");
242 dump_scope_blocks (dump_file, dump_flags);
247 struct gimple_opt_pass pass_build_cfg =
253 execute_build_cfg, /* execute */
256 0, /* static_pass_number */
257 TV_TREE_CFG, /* tv_id */
258 PROP_gimple_leh, /* properties_required */
259 PROP_cfg, /* properties_provided */
260 0, /* properties_destroyed */
261 0, /* todo_flags_start */
262 TODO_verify_stmts | TODO_cleanup_cfg
263 | TODO_dump_func /* todo_flags_finish */
268 /* Return true if T is a computed goto. */
271 computed_goto_p (gimple t)
273 return (gimple_code (t) == GIMPLE_GOTO
274 && TREE_CODE (gimple_goto_dest (t)) != LABEL_DECL);
278 /* Search the CFG for any computed gotos. If found, factor them to a
279 common computed goto site. Also record the location of that site so
280 that we can un-factor the gotos after we have converted back to
284 factor_computed_gotos (void)
287 tree factored_label_decl = NULL;
289 gimple factored_computed_goto_label = NULL;
290 gimple factored_computed_goto = NULL;
292 /* We know there are one or more computed gotos in this function.
293 Examine the last statement in each basic block to see if the block
294 ends with a computed goto. */
298 gimple_stmt_iterator gsi = gsi_last_bb (bb);
304 last = gsi_stmt (gsi);
306 /* Ignore the computed goto we create when we factor the original
308 if (last == factored_computed_goto)
311 /* If the last statement is a computed goto, factor it. */
312 if (computed_goto_p (last))
316 /* The first time we find a computed goto we need to create
317 the factored goto block and the variable each original
318 computed goto will use for their goto destination. */
319 if (!factored_computed_goto)
321 basic_block new_bb = create_empty_bb (bb);
322 gimple_stmt_iterator new_gsi = gsi_start_bb (new_bb);
324 /* Create the destination of the factored goto. Each original
325 computed goto will put its desired destination into this
326 variable and jump to the label we create immediately
328 var = create_tmp_var (ptr_type_node, "gotovar");
330 /* Build a label for the new block which will contain the
331 factored computed goto. */
332 factored_label_decl = create_artificial_label (UNKNOWN_LOCATION);
333 factored_computed_goto_label
334 = gimple_build_label (factored_label_decl);
335 gsi_insert_after (&new_gsi, factored_computed_goto_label,
338 /* Build our new computed goto. */
339 factored_computed_goto = gimple_build_goto (var);
340 gsi_insert_after (&new_gsi, factored_computed_goto, GSI_NEW_STMT);
343 /* Copy the original computed goto's destination into VAR. */
344 assignment = gimple_build_assign (var, gimple_goto_dest (last));
345 gsi_insert_before (&gsi, assignment, GSI_SAME_STMT);
347 /* And re-vector the computed goto to the new destination. */
348 gimple_goto_set_dest (last, factored_label_decl);
354 /* Build a flowgraph for the sequence of stmts SEQ. */
357 make_blocks (gimple_seq seq)
359 gimple_stmt_iterator i = gsi_start (seq);
361 bool start_new_block = true;
362 bool first_stmt_of_seq = true;
363 basic_block bb = ENTRY_BLOCK_PTR;
365 while (!gsi_end_p (i))
372 /* If the statement starts a new basic block or if we have determined
373 in a previous pass that we need to create a new block for STMT, do
375 if (start_new_block || stmt_starts_bb_p (stmt, prev_stmt))
377 if (!first_stmt_of_seq)
378 seq = gsi_split_seq_before (&i);
379 bb = create_basic_block (seq, NULL, bb);
380 start_new_block = false;
383 /* Now add STMT to BB and create the subgraphs for special statement
385 gimple_set_bb (stmt, bb);
387 if (computed_goto_p (stmt))
388 found_computed_goto = true;
390 /* If STMT is a basic block terminator, set START_NEW_BLOCK for the
392 if (stmt_ends_bb_p (stmt))
394 /* If the stmt can make abnormal goto use a new temporary
395 for the assignment to the LHS. This makes sure the old value
396 of the LHS is available on the abnormal edge. Otherwise
397 we will end up with overlapping life-ranges for abnormal
399 if (gimple_has_lhs (stmt)
400 && stmt_can_make_abnormal_goto (stmt)
401 && is_gimple_reg_type (TREE_TYPE (gimple_get_lhs (stmt))))
403 tree lhs = gimple_get_lhs (stmt);
404 tree tmp = create_tmp_var (TREE_TYPE (lhs), NULL);
405 gimple s = gimple_build_assign (lhs, tmp);
406 gimple_set_location (s, gimple_location (stmt));
407 gimple_set_block (s, gimple_block (stmt));
408 gimple_set_lhs (stmt, tmp);
409 if (TREE_CODE (TREE_TYPE (tmp)) == COMPLEX_TYPE
410 || TREE_CODE (TREE_TYPE (tmp)) == VECTOR_TYPE)
411 DECL_GIMPLE_REG_P (tmp) = 1;
412 gsi_insert_after (&i, s, GSI_SAME_STMT);
414 start_new_block = true;
418 first_stmt_of_seq = false;
423 /* Create and return a new empty basic block after bb AFTER. */
426 create_bb (void *h, void *e, basic_block after)
432 /* Create and initialize a new basic block. Since alloc_block uses
433 ggc_alloc_cleared to allocate a basic block, we do not have to
434 clear the newly allocated basic block here. */
437 bb->index = last_basic_block;
439 bb->il.gimple = GGC_CNEW (struct gimple_bb_info);
440 set_bb_seq (bb, h ? (gimple_seq) h : gimple_seq_alloc ());
442 /* Add the new block to the linked list of blocks. */
443 link_block (bb, after);
445 /* Grow the basic block array if needed. */
446 if ((size_t) last_basic_block == VEC_length (basic_block, basic_block_info))
448 size_t new_size = last_basic_block + (last_basic_block + 3) / 4;
449 VEC_safe_grow_cleared (basic_block, gc, basic_block_info, new_size);
452 /* Add the newly created block to the array. */
453 SET_BASIC_BLOCK (last_basic_block, bb);
462 /*---------------------------------------------------------------------------
464 ---------------------------------------------------------------------------*/
466 /* Fold COND_EXPR_COND of each COND_EXPR. */
469 fold_cond_expr_cond (void)
475 gimple stmt = last_stmt (bb);
477 if (stmt && gimple_code (stmt) == GIMPLE_COND)
479 location_t loc = gimple_location (stmt);
483 fold_defer_overflow_warnings ();
484 cond = fold_binary_loc (loc, gimple_cond_code (stmt), boolean_type_node,
485 gimple_cond_lhs (stmt), gimple_cond_rhs (stmt));
488 zerop = integer_zerop (cond);
489 onep = integer_onep (cond);
492 zerop = onep = false;
494 fold_undefer_overflow_warnings (zerop || onep,
496 WARN_STRICT_OVERFLOW_CONDITIONAL);
498 gimple_cond_make_false (stmt);
500 gimple_cond_make_true (stmt);
505 /* Join all the blocks in the flowgraph. */
511 struct omp_region *cur_region = NULL;
513 /* Create an edge from entry to the first block with executable
515 make_edge (ENTRY_BLOCK_PTR, BASIC_BLOCK (NUM_FIXED_BLOCKS), EDGE_FALLTHRU);
517 /* Traverse the basic block array placing edges. */
520 gimple last = last_stmt (bb);
525 enum gimple_code code = gimple_code (last);
529 make_goto_expr_edges (bb);
533 make_edge (bb, EXIT_BLOCK_PTR, 0);
537 make_cond_expr_edges (bb);
541 make_gimple_switch_edges (bb);
545 make_eh_edges (last);
550 /* If this function receives a nonlocal goto, then we need to
551 make edges from this call site to all the nonlocal goto
553 if (stmt_can_make_abnormal_goto (last))
554 make_abnormal_goto_edges (bb, true);
556 /* If this statement has reachable exception handlers, then
557 create abnormal edges to them. */
558 make_eh_edges (last);
560 /* Some calls are known not to return. */
561 fallthru = !(gimple_call_flags (last) & ECF_NORETURN);
565 /* A GIMPLE_ASSIGN may throw internally and thus be considered
567 if (is_ctrl_altering_stmt (last))
569 make_eh_edges (last);
574 case GIMPLE_OMP_PARALLEL:
575 case GIMPLE_OMP_TASK:
577 case GIMPLE_OMP_SINGLE:
578 case GIMPLE_OMP_MASTER:
579 case GIMPLE_OMP_ORDERED:
580 case GIMPLE_OMP_CRITICAL:
581 case GIMPLE_OMP_SECTION:
582 cur_region = new_omp_region (bb, code, cur_region);
586 case GIMPLE_OMP_SECTIONS:
587 cur_region = new_omp_region (bb, code, cur_region);
591 case GIMPLE_OMP_SECTIONS_SWITCH:
596 case GIMPLE_OMP_ATOMIC_LOAD:
597 case GIMPLE_OMP_ATOMIC_STORE:
602 case GIMPLE_OMP_RETURN:
603 /* In the case of a GIMPLE_OMP_SECTION, the edge will go
604 somewhere other than the next block. This will be
606 cur_region->exit = bb;
607 fallthru = cur_region->type != GIMPLE_OMP_SECTION;
608 cur_region = cur_region->outer;
611 case GIMPLE_OMP_CONTINUE:
612 cur_region->cont = bb;
613 switch (cur_region->type)
616 /* Mark all GIMPLE_OMP_FOR and GIMPLE_OMP_CONTINUE
617 succs edges as abnormal to prevent splitting
619 single_succ_edge (cur_region->entry)->flags |= EDGE_ABNORMAL;
620 /* Make the loopback edge. */
621 make_edge (bb, single_succ (cur_region->entry),
624 /* Create an edge from GIMPLE_OMP_FOR to exit, which
625 corresponds to the case that the body of the loop
626 is not executed at all. */
627 make_edge (cur_region->entry, bb->next_bb, EDGE_ABNORMAL);
628 make_edge (bb, bb->next_bb, EDGE_FALLTHRU | EDGE_ABNORMAL);
632 case GIMPLE_OMP_SECTIONS:
633 /* Wire up the edges into and out of the nested sections. */
635 basic_block switch_bb = single_succ (cur_region->entry);
637 struct omp_region *i;
638 for (i = cur_region->inner; i ; i = i->next)
640 gcc_assert (i->type == GIMPLE_OMP_SECTION);
641 make_edge (switch_bb, i->entry, 0);
642 make_edge (i->exit, bb, EDGE_FALLTHRU);
645 /* Make the loopback edge to the block with
646 GIMPLE_OMP_SECTIONS_SWITCH. */
647 make_edge (bb, switch_bb, 0);
649 /* Make the edge from the switch to exit. */
650 make_edge (switch_bb, bb->next_bb, 0);
661 gcc_assert (!stmt_ends_bb_p (last));
670 make_edge (bb, bb->next_bb, EDGE_FALLTHRU);
672 assign_discriminator (gimple_location (last), bb->next_bb);
679 /* Fold COND_EXPR_COND of each COND_EXPR. */
680 fold_cond_expr_cond ();
683 /* Trivial hash function for a location_t. ITEM is a pointer to
684 a hash table entry that maps a location_t to a discriminator. */
687 locus_map_hash (const void *item)
689 return ((const struct locus_discrim_map *) item)->locus;
692 /* Equality function for the locus-to-discriminator map. VA and VB
693 point to the two hash table entries to compare. */
696 locus_map_eq (const void *va, const void *vb)
698 const struct locus_discrim_map *a = (const struct locus_discrim_map *) va;
699 const struct locus_discrim_map *b = (const struct locus_discrim_map *) vb;
700 return a->locus == b->locus;
703 /* Find the next available discriminator value for LOCUS. The
704 discriminator distinguishes among several basic blocks that
705 share a common locus, allowing for more accurate sample-based
709 next_discriminator_for_locus (location_t locus)
711 struct locus_discrim_map item;
712 struct locus_discrim_map **slot;
715 item.discriminator = 0;
716 slot = (struct locus_discrim_map **)
717 htab_find_slot_with_hash (discriminator_per_locus, (void *) &item,
718 (hashval_t) locus, INSERT);
720 if (*slot == HTAB_EMPTY_ENTRY)
722 *slot = XNEW (struct locus_discrim_map);
724 (*slot)->locus = locus;
725 (*slot)->discriminator = 0;
727 (*slot)->discriminator++;
728 return (*slot)->discriminator;
731 /* Return TRUE if LOCUS1 and LOCUS2 refer to the same source line. */
734 same_line_p (location_t locus1, location_t locus2)
736 expanded_location from, to;
738 if (locus1 == locus2)
741 from = expand_location (locus1);
742 to = expand_location (locus2);
744 if (from.line != to.line)
746 if (from.file == to.file)
748 return (from.file != NULL
750 && strcmp (from.file, to.file) == 0);
753 /* Assign a unique discriminator value to block BB if it begins at the same
754 LOCUS as its predecessor block. */
757 assign_discriminator (location_t locus, basic_block bb)
759 gimple first_in_to_bb, last_in_to_bb;
761 if (locus == 0 || bb->discriminator != 0)
764 first_in_to_bb = first_non_label_stmt (bb);
765 last_in_to_bb = last_stmt (bb);
766 if ((first_in_to_bb && same_line_p (locus, gimple_location (first_in_to_bb)))
767 || (last_in_to_bb && same_line_p (locus, gimple_location (last_in_to_bb))))
768 bb->discriminator = next_discriminator_for_locus (locus);
771 /* Create the edges for a GIMPLE_COND starting at block BB. */
774 make_cond_expr_edges (basic_block bb)
776 gimple entry = last_stmt (bb);
777 gimple then_stmt, else_stmt;
778 basic_block then_bb, else_bb;
779 tree then_label, else_label;
781 location_t entry_locus;
784 gcc_assert (gimple_code (entry) == GIMPLE_COND);
786 entry_locus = gimple_location (entry);
788 /* Entry basic blocks for each component. */
789 then_label = gimple_cond_true_label (entry);
790 else_label = gimple_cond_false_label (entry);
791 then_bb = label_to_block (then_label);
792 else_bb = label_to_block (else_label);
793 then_stmt = first_stmt (then_bb);
794 else_stmt = first_stmt (else_bb);
796 e = make_edge (bb, then_bb, EDGE_TRUE_VALUE);
797 assign_discriminator (entry_locus, then_bb);
798 e->goto_locus = gimple_location (then_stmt);
800 e->goto_block = gimple_block (then_stmt);
801 e = make_edge (bb, else_bb, EDGE_FALSE_VALUE);
804 assign_discriminator (entry_locus, else_bb);
805 e->goto_locus = gimple_location (else_stmt);
807 e->goto_block = gimple_block (else_stmt);
810 /* We do not need the labels anymore. */
811 gimple_cond_set_true_label (entry, NULL_TREE);
812 gimple_cond_set_false_label (entry, NULL_TREE);
816 /* Called for each element in the hash table (P) as we delete the
817 edge to cases hash table.
819 Clear all the TREE_CHAINs to prevent problems with copying of
820 SWITCH_EXPRs and structure sharing rules, then free the hash table
824 edge_to_cases_cleanup (const void *key ATTRIBUTE_UNUSED, void **value,
825 void *data ATTRIBUTE_UNUSED)
829 for (t = (tree) *value; t; t = next)
831 next = TREE_CHAIN (t);
832 TREE_CHAIN (t) = NULL;
839 /* Start recording information mapping edges to case labels. */
842 start_recording_case_labels (void)
844 gcc_assert (edge_to_cases == NULL);
845 edge_to_cases = pointer_map_create ();
848 /* Return nonzero if we are recording information for case labels. */
851 recording_case_labels_p (void)
853 return (edge_to_cases != NULL);
856 /* Stop recording information mapping edges to case labels and
857 remove any information we have recorded. */
859 end_recording_case_labels (void)
861 pointer_map_traverse (edge_to_cases, edge_to_cases_cleanup, NULL);
862 pointer_map_destroy (edge_to_cases);
863 edge_to_cases = NULL;
866 /* If we are inside a {start,end}_recording_cases block, then return
867 a chain of CASE_LABEL_EXPRs from T which reference E.
869 Otherwise return NULL. */
872 get_cases_for_edge (edge e, gimple t)
877 /* If we are not recording cases, then we do not have CASE_LABEL_EXPR
878 chains available. Return NULL so the caller can detect this case. */
879 if (!recording_case_labels_p ())
882 slot = pointer_map_contains (edge_to_cases, e);
886 /* If we did not find E in the hash table, then this must be the first
887 time we have been queried for information about E & T. Add all the
888 elements from T to the hash table then perform the query again. */
890 n = gimple_switch_num_labels (t);
891 for (i = 0; i < n; i++)
893 tree elt = gimple_switch_label (t, i);
894 tree lab = CASE_LABEL (elt);
895 basic_block label_bb = label_to_block (lab);
896 edge this_edge = find_edge (e->src, label_bb);
898 /* Add it to the chain of CASE_LABEL_EXPRs referencing E, or create
900 slot = pointer_map_insert (edge_to_cases, this_edge);
901 TREE_CHAIN (elt) = (tree) *slot;
905 return (tree) *pointer_map_contains (edge_to_cases, e);
908 /* Create the edges for a GIMPLE_SWITCH starting at block BB. */
911 make_gimple_switch_edges (basic_block bb)
913 gimple entry = last_stmt (bb);
914 location_t entry_locus;
917 entry_locus = gimple_location (entry);
919 n = gimple_switch_num_labels (entry);
921 for (i = 0; i < n; ++i)
923 tree lab = CASE_LABEL (gimple_switch_label (entry, i));
924 basic_block label_bb = label_to_block (lab);
925 make_edge (bb, label_bb, 0);
926 assign_discriminator (entry_locus, label_bb);
931 /* Return the basic block holding label DEST. */
934 label_to_block_fn (struct function *ifun, tree dest)
936 int uid = LABEL_DECL_UID (dest);
938 /* We would die hard when faced by an undefined label. Emit a label to
939 the very first basic block. This will hopefully make even the dataflow
940 and undefined variable warnings quite right. */
941 if ((errorcount || sorrycount) && uid < 0)
943 gimple_stmt_iterator gsi = gsi_start_bb (BASIC_BLOCK (NUM_FIXED_BLOCKS));
946 stmt = gimple_build_label (dest);
947 gsi_insert_before (&gsi, stmt, GSI_NEW_STMT);
948 uid = LABEL_DECL_UID (dest);
950 if (VEC_length (basic_block, ifun->cfg->x_label_to_block_map)
951 <= (unsigned int) uid)
953 return VEC_index (basic_block, ifun->cfg->x_label_to_block_map, uid);
956 /* Create edges for an abnormal goto statement at block BB. If FOR_CALL
957 is true, the source statement is a CALL_EXPR instead of a GOTO_EXPR. */
960 make_abnormal_goto_edges (basic_block bb, bool for_call)
962 basic_block target_bb;
963 gimple_stmt_iterator gsi;
965 FOR_EACH_BB (target_bb)
966 for (gsi = gsi_start_bb (target_bb); !gsi_end_p (gsi); gsi_next (&gsi))
968 gimple label_stmt = gsi_stmt (gsi);
971 if (gimple_code (label_stmt) != GIMPLE_LABEL)
974 target = gimple_label_label (label_stmt);
976 /* Make an edge to every label block that has been marked as a
977 potential target for a computed goto or a non-local goto. */
978 if ((FORCED_LABEL (target) && !for_call)
979 || (DECL_NONLOCAL (target) && for_call))
981 make_edge (bb, target_bb, EDGE_ABNORMAL);
987 /* Create edges for a goto statement at block BB. */
990 make_goto_expr_edges (basic_block bb)
992 gimple_stmt_iterator last = gsi_last_bb (bb);
993 gimple goto_t = gsi_stmt (last);
995 /* A simple GOTO creates normal edges. */
996 if (simple_goto_p (goto_t))
998 tree dest = gimple_goto_dest (goto_t);
999 basic_block label_bb = label_to_block (dest);
1000 edge e = make_edge (bb, label_bb, EDGE_FALLTHRU);
1001 e->goto_locus = gimple_location (goto_t);
1002 assign_discriminator (e->goto_locus, label_bb);
1004 e->goto_block = gimple_block (goto_t);
1005 gsi_remove (&last, true);
1009 /* A computed GOTO creates abnormal edges. */
1010 make_abnormal_goto_edges (bb, false);
1014 /*---------------------------------------------------------------------------
1016 ---------------------------------------------------------------------------*/
1018 /* Cleanup useless labels in basic blocks. This is something we wish
1019 to do early because it allows us to group case labels before creating
1020 the edges for the CFG, and it speeds up block statement iterators in
1021 all passes later on.
1022 We rerun this pass after CFG is created, to get rid of the labels that
1023 are no longer referenced. After then we do not run it any more, since
1024 (almost) no new labels should be created. */
1026 /* A map from basic block index to the leading label of that block. */
1027 static struct label_record
1032 /* True if the label is referenced from somewhere. */
1036 /* Callback for for_each_eh_region. Helper for cleanup_dead_labels. */
1038 update_eh_label (struct eh_region_d *region)
1040 tree old_label = get_eh_region_tree_label (region);
1044 basic_block bb = label_to_block (old_label);
1046 /* ??? After optimizing, there may be EH regions with labels
1047 that have already been removed from the function body, so
1048 there is no basic block for them. */
1052 new_label = label_for_bb[bb->index].label;
1053 label_for_bb[bb->index].used = true;
1054 set_eh_region_tree_label (region, new_label);
1059 /* Given LABEL return the first label in the same basic block. */
1062 main_block_label (tree label)
1064 basic_block bb = label_to_block (label);
1065 tree main_label = label_for_bb[bb->index].label;
1067 /* label_to_block possibly inserted undefined label into the chain. */
1070 label_for_bb[bb->index].label = label;
1074 label_for_bb[bb->index].used = true;
1078 /* Cleanup redundant labels. This is a three-step process:
1079 1) Find the leading label for each block.
1080 2) Redirect all references to labels to the leading labels.
1081 3) Cleanup all useless labels. */
1084 cleanup_dead_labels (void)
1087 label_for_bb = XCNEWVEC (struct label_record, last_basic_block);
1089 /* Find a suitable label for each block. We use the first user-defined
1090 label if there is one, or otherwise just the first label we see. */
1093 gimple_stmt_iterator i;
1095 for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
1098 gimple stmt = gsi_stmt (i);
1100 if (gimple_code (stmt) != GIMPLE_LABEL)
1103 label = gimple_label_label (stmt);
1105 /* If we have not yet seen a label for the current block,
1106 remember this one and see if there are more labels. */
1107 if (!label_for_bb[bb->index].label)
1109 label_for_bb[bb->index].label = label;
1113 /* If we did see a label for the current block already, but it
1114 is an artificially created label, replace it if the current
1115 label is a user defined label. */
1116 if (!DECL_ARTIFICIAL (label)
1117 && DECL_ARTIFICIAL (label_for_bb[bb->index].label))
1119 label_for_bb[bb->index].label = label;
1125 /* Now redirect all jumps/branches to the selected label.
1126 First do so for each block ending in a control statement. */
1129 gimple stmt = last_stmt (bb);
1133 switch (gimple_code (stmt))
1137 tree true_label = gimple_cond_true_label (stmt);
1138 tree false_label = gimple_cond_false_label (stmt);
1141 gimple_cond_set_true_label (stmt, main_block_label (true_label));
1143 gimple_cond_set_false_label (stmt, main_block_label (false_label));
1149 size_t i, n = gimple_switch_num_labels (stmt);
1151 /* Replace all destination labels. */
1152 for (i = 0; i < n; ++i)
1154 tree case_label = gimple_switch_label (stmt, i);
1155 tree label = main_block_label (CASE_LABEL (case_label));
1156 CASE_LABEL (case_label) = label;
1161 /* We have to handle gotos until they're removed, and we don't
1162 remove them until after we've created the CFG edges. */
1164 if (!computed_goto_p (stmt))
1166 tree new_dest = main_block_label (gimple_goto_dest (stmt));
1167 gimple_goto_set_dest (stmt, new_dest);
1176 for_each_eh_region (update_eh_label);
1178 /* Finally, purge dead labels. All user-defined labels and labels that
1179 can be the target of non-local gotos and labels which have their
1180 address taken are preserved. */
1183 gimple_stmt_iterator i;
1184 tree label_for_this_bb = label_for_bb[bb->index].label;
1186 if (!label_for_this_bb)
1189 /* If the main label of the block is unused, we may still remove it. */
1190 if (!label_for_bb[bb->index].used)
1191 label_for_this_bb = NULL;
1193 for (i = gsi_start_bb (bb); !gsi_end_p (i); )
1196 gimple stmt = gsi_stmt (i);
1198 if (gimple_code (stmt) != GIMPLE_LABEL)
1201 label = gimple_label_label (stmt);
1203 if (label == label_for_this_bb
1204 || !DECL_ARTIFICIAL (label)
1205 || DECL_NONLOCAL (label)
1206 || FORCED_LABEL (label))
1209 gsi_remove (&i, true);
1213 free (label_for_bb);
1216 /* Look for blocks ending in a multiway branch (a SWITCH_EXPR in GIMPLE),
1217 and scan the sorted vector of cases. Combine the ones jumping to the
1219 Eg. three separate entries 1: 2: 3: become one entry 1..3: */
1222 group_case_labels (void)
1228 gimple stmt = last_stmt (bb);
1229 if (stmt && gimple_code (stmt) == GIMPLE_SWITCH)
1231 int old_size = gimple_switch_num_labels (stmt);
1232 int i, j, new_size = old_size;
1233 tree default_case = NULL_TREE;
1234 tree default_label = NULL_TREE;
1237 /* The default label is always the first case in a switch
1238 statement after gimplification if it was not optimized
1240 if (!CASE_LOW (gimple_switch_default_label (stmt))
1241 && !CASE_HIGH (gimple_switch_default_label (stmt)))
1243 default_case = gimple_switch_default_label (stmt);
1244 default_label = CASE_LABEL (default_case);
1248 has_default = false;
1250 /* Look for possible opportunities to merge cases. */
1255 while (i < old_size)
1257 tree base_case, base_label, base_high;
1258 base_case = gimple_switch_label (stmt, i);
1260 gcc_assert (base_case);
1261 base_label = CASE_LABEL (base_case);
1263 /* Discard cases that have the same destination as the
1265 if (base_label == default_label)
1267 gimple_switch_set_label (stmt, i, NULL_TREE);
1273 base_high = CASE_HIGH (base_case)
1274 ? CASE_HIGH (base_case)
1275 : CASE_LOW (base_case);
1278 /* Try to merge case labels. Break out when we reach the end
1279 of the label vector or when we cannot merge the next case
1280 label with the current one. */
1281 while (i < old_size)
1283 tree merge_case = gimple_switch_label (stmt, i);
1284 tree merge_label = CASE_LABEL (merge_case);
1285 tree t = int_const_binop (PLUS_EXPR, base_high,
1286 integer_one_node, 1);
1288 /* Merge the cases if they jump to the same place,
1289 and their ranges are consecutive. */
1290 if (merge_label == base_label
1291 && tree_int_cst_equal (CASE_LOW (merge_case), t))
1293 base_high = CASE_HIGH (merge_case) ?
1294 CASE_HIGH (merge_case) : CASE_LOW (merge_case);
1295 CASE_HIGH (base_case) = base_high;
1296 gimple_switch_set_label (stmt, i, NULL_TREE);
1305 /* Compress the case labels in the label vector, and adjust the
1306 length of the vector. */
1307 for (i = 0, j = 0; i < new_size; i++)
1309 while (! gimple_switch_label (stmt, j))
1311 gimple_switch_set_label (stmt, i,
1312 gimple_switch_label (stmt, j++));
1315 gcc_assert (new_size <= old_size);
1316 gimple_switch_set_num_labels (stmt, new_size);
1321 /* Checks whether we can merge block B into block A. */
1324 gimple_can_merge_blocks_p (basic_block a, basic_block b)
1327 gimple_stmt_iterator gsi;
1330 if (!single_succ_p (a))
1333 if (single_succ_edge (a)->flags & (EDGE_ABNORMAL | EDGE_EH))
1336 if (single_succ (a) != b)
1339 if (!single_pred_p (b))
1342 if (b == EXIT_BLOCK_PTR)
1345 /* If A ends by a statement causing exceptions or something similar, we
1346 cannot merge the blocks. */
1347 stmt = last_stmt (a);
1348 if (stmt && stmt_ends_bb_p (stmt))
1351 /* Do not allow a block with only a non-local label to be merged. */
1353 && gimple_code (stmt) == GIMPLE_LABEL
1354 && DECL_NONLOCAL (gimple_label_label (stmt)))
1357 /* Examine the labels at the beginning of B. */
1358 for (gsi = gsi_start_bb (b); !gsi_end_p (gsi); gsi_next (&gsi))
1361 stmt = gsi_stmt (gsi);
1362 if (gimple_code (stmt) != GIMPLE_LABEL)
1364 lab = gimple_label_label (stmt);
1366 /* Do not remove user labels. */
1367 if (!DECL_ARTIFICIAL (lab))
1371 /* Protect the loop latches. */
1372 if (current_loops && b->loop_father->latch == b)
1375 /* It must be possible to eliminate all phi nodes in B. If ssa form
1376 is not up-to-date, we cannot eliminate any phis; however, if only
1377 some symbols as whole are marked for renaming, this is not a problem,
1378 as phi nodes for those symbols are irrelevant in updating anyway. */
1379 phis = phi_nodes (b);
1380 if (!gimple_seq_empty_p (phis))
1382 gimple_stmt_iterator i;
1384 if (name_mappings_registered_p ())
1387 for (i = gsi_start (phis); !gsi_end_p (i); gsi_next (&i))
1389 gimple phi = gsi_stmt (i);
1391 if (!is_gimple_reg (gimple_phi_result (phi))
1392 && !may_propagate_copy (gimple_phi_result (phi),
1393 gimple_phi_arg_def (phi, 0)))
1401 /* Return true if the var whose chain of uses starts at PTR has no
1404 has_zero_uses_1 (const ssa_use_operand_t *head)
1406 const ssa_use_operand_t *ptr;
1408 for (ptr = head->next; ptr != head; ptr = ptr->next)
1409 if (!is_gimple_debug (USE_STMT (ptr)))
1415 /* Return true if the var whose chain of uses starts at PTR has a
1416 single nondebug use. Set USE_P and STMT to that single nondebug
1417 use, if so, or to NULL otherwise. */
1419 single_imm_use_1 (const ssa_use_operand_t *head,
1420 use_operand_p *use_p, gimple *stmt)
1422 ssa_use_operand_t *ptr, *single_use = 0;
1424 for (ptr = head->next; ptr != head; ptr = ptr->next)
1425 if (!is_gimple_debug (USE_STMT (ptr)))
1436 *use_p = single_use;
1439 *stmt = single_use ? single_use->loc.stmt : NULL;
1441 return !!single_use;
1444 /* Replaces all uses of NAME by VAL. */
1447 replace_uses_by (tree name, tree val)
1449 imm_use_iterator imm_iter;
1454 FOR_EACH_IMM_USE_STMT (stmt, imm_iter, name)
1456 FOR_EACH_IMM_USE_ON_STMT (use, imm_iter)
1458 replace_exp (use, val);
1460 if (gimple_code (stmt) == GIMPLE_PHI)
1462 e = gimple_phi_arg_edge (stmt, PHI_ARG_INDEX_FROM_USE (use));
1463 if (e->flags & EDGE_ABNORMAL)
1465 /* This can only occur for virtual operands, since
1466 for the real ones SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name))
1467 would prevent replacement. */
1468 gcc_assert (!is_gimple_reg (name));
1469 SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val) = 1;
1474 if (gimple_code (stmt) != GIMPLE_PHI)
1478 fold_stmt_inplace (stmt);
1479 if (cfgcleanup_altered_bbs)
1480 bitmap_set_bit (cfgcleanup_altered_bbs, gimple_bb (stmt)->index);
1482 /* FIXME. This should go in update_stmt. */
1483 for (i = 0; i < gimple_num_ops (stmt); i++)
1485 tree op = gimple_op (stmt, i);
1486 /* Operands may be empty here. For example, the labels
1487 of a GIMPLE_COND are nulled out following the creation
1488 of the corresponding CFG edges. */
1489 if (op && TREE_CODE (op) == ADDR_EXPR)
1490 recompute_tree_invariant_for_addr_expr (op);
1493 maybe_clean_or_replace_eh_stmt (stmt, stmt);
1498 gcc_assert (has_zero_uses (name));
1500 /* Also update the trees stored in loop structures. */
1506 FOR_EACH_LOOP (li, loop, 0)
1508 substitute_in_loop_info (loop, name, val);
1513 /* Merge block B into block A. */
1516 gimple_merge_blocks (basic_block a, basic_block b)
1518 gimple_stmt_iterator last, gsi, psi;
1519 gimple_seq phis = phi_nodes (b);
1522 fprintf (dump_file, "Merging blocks %d and %d\n", a->index, b->index);
1524 /* Remove all single-valued PHI nodes from block B of the form
1525 V_i = PHI <V_j> by propagating V_j to all the uses of V_i. */
1526 gsi = gsi_last_bb (a);
1527 for (psi = gsi_start (phis); !gsi_end_p (psi); )
1529 gimple phi = gsi_stmt (psi);
1530 tree def = gimple_phi_result (phi), use = gimple_phi_arg_def (phi, 0);
1532 bool may_replace_uses = !is_gimple_reg (def)
1533 || may_propagate_copy (def, use);
1535 /* In case we maintain loop closed ssa form, do not propagate arguments
1536 of loop exit phi nodes. */
1538 && loops_state_satisfies_p (LOOP_CLOSED_SSA)
1539 && is_gimple_reg (def)
1540 && TREE_CODE (use) == SSA_NAME
1541 && a->loop_father != b->loop_father)
1542 may_replace_uses = false;
1544 if (!may_replace_uses)
1546 gcc_assert (is_gimple_reg (def));
1548 /* Note that just emitting the copies is fine -- there is no problem
1549 with ordering of phi nodes. This is because A is the single
1550 predecessor of B, therefore results of the phi nodes cannot
1551 appear as arguments of the phi nodes. */
1552 copy = gimple_build_assign (def, use);
1553 gsi_insert_after (&gsi, copy, GSI_NEW_STMT);
1554 remove_phi_node (&psi, false);
1558 /* If we deal with a PHI for virtual operands, we can simply
1559 propagate these without fussing with folding or updating
1561 if (!is_gimple_reg (def))
1563 imm_use_iterator iter;
1564 use_operand_p use_p;
1567 FOR_EACH_IMM_USE_STMT (stmt, iter, def)
1568 FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
1569 SET_USE (use_p, use);
1572 replace_uses_by (def, use);
1574 remove_phi_node (&psi, true);
1578 /* Ensure that B follows A. */
1579 move_block_after (b, a);
1581 gcc_assert (single_succ_edge (a)->flags & EDGE_FALLTHRU);
1582 gcc_assert (!last_stmt (a) || !stmt_ends_bb_p (last_stmt (a)));
1584 /* Remove labels from B and set gimple_bb to A for other statements. */
1585 for (gsi = gsi_start_bb (b); !gsi_end_p (gsi);)
1587 if (gimple_code (gsi_stmt (gsi)) == GIMPLE_LABEL)
1589 gimple label = gsi_stmt (gsi);
1591 gsi_remove (&gsi, false);
1593 /* Now that we can thread computed gotos, we might have
1594 a situation where we have a forced label in block B
1595 However, the label at the start of block B might still be
1596 used in other ways (think about the runtime checking for
1597 Fortran assigned gotos). So we can not just delete the
1598 label. Instead we move the label to the start of block A. */
1599 if (FORCED_LABEL (gimple_label_label (label)))
1601 gimple_stmt_iterator dest_gsi = gsi_start_bb (a);
1602 gsi_insert_before (&dest_gsi, label, GSI_NEW_STMT);
1607 gimple_set_bb (gsi_stmt (gsi), a);
1612 /* Merge the sequences. */
1613 last = gsi_last_bb (a);
1614 gsi_insert_seq_after (&last, bb_seq (b), GSI_NEW_STMT);
1615 set_bb_seq (b, NULL);
1617 if (cfgcleanup_altered_bbs)
1618 bitmap_set_bit (cfgcleanup_altered_bbs, a->index);
1622 /* Return the one of two successors of BB that is not reachable by a
1623 complex edge, if there is one. Else, return BB. We use
1624 this in optimizations that use post-dominators for their heuristics,
1625 to catch the cases in C++ where function calls are involved. */
1628 single_noncomplex_succ (basic_block bb)
1631 if (EDGE_COUNT (bb->succs) != 2)
1634 e0 = EDGE_SUCC (bb, 0);
1635 e1 = EDGE_SUCC (bb, 1);
1636 if (e0->flags & EDGE_COMPLEX)
1638 if (e1->flags & EDGE_COMPLEX)
1645 /* Walk the function tree removing unnecessary statements.
1647 * Empty statement nodes are removed
1649 * Unnecessary TRY_FINALLY and TRY_CATCH blocks are removed
1651 * Unnecessary COND_EXPRs are removed
1653 * Some unnecessary BIND_EXPRs are removed
1655 * GOTO_EXPRs immediately preceding destination are removed.
1657 Clearly more work could be done. The trick is doing the analysis
1658 and removal fast enough to be a net improvement in compile times.
1660 Note that when we remove a control structure such as a COND_EXPR
1661 BIND_EXPR, or TRY block, we will need to repeat this optimization pass
1662 to ensure we eliminate all the useless code. */
1671 gimple_stmt_iterator last_goto_gsi;
1675 static void remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *);
1677 /* Given a statement sequence, find the first executable statement with
1678 location information, and warn that it is unreachable. When searching,
1679 descend into containers in execution order. */
1682 remove_useless_stmts_warn_notreached (gimple_seq stmts)
1684 gimple_stmt_iterator gsi;
1686 for (gsi = gsi_start (stmts); !gsi_end_p (gsi); gsi_next (&gsi))
1688 gimple stmt = gsi_stmt (gsi);
1690 if (gimple_no_warning_p (stmt)) return false;
1692 if (gimple_has_location (stmt))
1694 location_t loc = gimple_location (stmt);
1695 if (LOCATION_LINE (loc) > 0)
1697 warning_at (loc, OPT_Wunreachable_code, "will never be executed");
1702 switch (gimple_code (stmt))
1704 /* Unfortunately, we need the CFG now to detect unreachable
1705 branches in a conditional, so conditionals are not handled here. */
1708 if (remove_useless_stmts_warn_notreached (gimple_try_eval (stmt)))
1710 if (remove_useless_stmts_warn_notreached (gimple_try_cleanup (stmt)))
1715 return remove_useless_stmts_warn_notreached (gimple_catch_handler (stmt));
1717 case GIMPLE_EH_FILTER:
1718 return remove_useless_stmts_warn_notreached (gimple_eh_filter_failure (stmt));
1721 return remove_useless_stmts_warn_notreached (gimple_bind_body (stmt));
1731 /* Helper for remove_useless_stmts_1. Handle GIMPLE_COND statements. */
1734 remove_useless_stmts_cond (gimple_stmt_iterator *gsi, struct rus_data *data)
1736 gimple stmt = gsi_stmt (*gsi);
1738 /* The folded result must still be a conditional statement. */
1740 gcc_assert (gsi_stmt (*gsi) == stmt);
1742 data->may_branch = true;
1744 /* Replace trivial conditionals with gotos. */
1745 if (gimple_cond_true_p (stmt))
1747 /* Goto THEN label. */
1748 tree then_label = gimple_cond_true_label (stmt);
1750 gsi_replace (gsi, gimple_build_goto (then_label), false);
1751 data->last_goto_gsi = *gsi;
1752 data->last_was_goto = true;
1753 data->repeat = true;
1755 else if (gimple_cond_false_p (stmt))
1757 /* Goto ELSE label. */
1758 tree else_label = gimple_cond_false_label (stmt);
1760 gsi_replace (gsi, gimple_build_goto (else_label), false);
1761 data->last_goto_gsi = *gsi;
1762 data->last_was_goto = true;
1763 data->repeat = true;
1767 tree then_label = gimple_cond_true_label (stmt);
1768 tree else_label = gimple_cond_false_label (stmt);
1770 if (then_label == else_label)
1772 /* Goto common destination. */
1773 gsi_replace (gsi, gimple_build_goto (then_label), false);
1774 data->last_goto_gsi = *gsi;
1775 data->last_was_goto = true;
1776 data->repeat = true;
1782 data->last_was_goto = false;
1785 /* Helper for remove_useless_stmts_1.
1786 Handle the try-finally case for GIMPLE_TRY statements. */
1789 remove_useless_stmts_tf (gimple_stmt_iterator *gsi, struct rus_data *data)
1791 bool save_may_branch, save_may_throw;
1792 bool this_may_branch, this_may_throw;
1794 gimple_seq eval_seq, cleanup_seq;
1795 gimple_stmt_iterator eval_gsi, cleanup_gsi;
1797 gimple stmt = gsi_stmt (*gsi);
1799 /* Collect may_branch and may_throw information for the body only. */
1800 save_may_branch = data->may_branch;
1801 save_may_throw = data->may_throw;
1802 data->may_branch = false;
1803 data->may_throw = false;
1804 data->last_was_goto = false;
1806 eval_seq = gimple_try_eval (stmt);
1807 eval_gsi = gsi_start (eval_seq);
1808 remove_useless_stmts_1 (&eval_gsi, data);
1810 this_may_branch = data->may_branch;
1811 this_may_throw = data->may_throw;
1812 data->may_branch |= save_may_branch;
1813 data->may_throw |= save_may_throw;
1814 data->last_was_goto = false;
1816 cleanup_seq = gimple_try_cleanup (stmt);
1817 cleanup_gsi = gsi_start (cleanup_seq);
1818 remove_useless_stmts_1 (&cleanup_gsi, data);
1820 /* If the body is empty, then we can emit the FINALLY block without
1821 the enclosing TRY_FINALLY_EXPR. */
1822 if (gimple_seq_empty_p (eval_seq))
1824 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1825 gsi_remove (gsi, false);
1826 data->repeat = true;
1829 /* If the handler is empty, then we can emit the TRY block without
1830 the enclosing TRY_FINALLY_EXPR. */
1831 else if (gimple_seq_empty_p (cleanup_seq))
1833 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1834 gsi_remove (gsi, false);
1835 data->repeat = true;
1838 /* If the body neither throws, nor branches, then we can safely
1839 string the TRY and FINALLY blocks together. */
1840 else if (!this_may_branch && !this_may_throw)
1842 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1843 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1844 gsi_remove (gsi, false);
1845 data->repeat = true;
1851 /* Helper for remove_useless_stmts_1.
1852 Handle the try-catch case for GIMPLE_TRY statements. */
1855 remove_useless_stmts_tc (gimple_stmt_iterator *gsi, struct rus_data *data)
1857 bool save_may_throw, this_may_throw;
1859 gimple_seq eval_seq, cleanup_seq, handler_seq, failure_seq;
1860 gimple_stmt_iterator eval_gsi, cleanup_gsi, handler_gsi, failure_gsi;
1862 gimple stmt = gsi_stmt (*gsi);
1864 /* Collect may_throw information for the body only. */
1865 save_may_throw = data->may_throw;
1866 data->may_throw = false;
1867 data->last_was_goto = false;
1869 eval_seq = gimple_try_eval (stmt);
1870 eval_gsi = gsi_start (eval_seq);
1871 remove_useless_stmts_1 (&eval_gsi, data);
1873 this_may_throw = data->may_throw;
1874 data->may_throw = save_may_throw;
1876 cleanup_seq = gimple_try_cleanup (stmt);
1878 /* If the body cannot throw, then we can drop the entire TRY_CATCH_EXPR. */
1879 if (!this_may_throw)
1881 if (warn_notreached)
1883 remove_useless_stmts_warn_notreached (cleanup_seq);
1885 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1886 gsi_remove (gsi, false);
1887 data->repeat = true;
1891 /* Process the catch clause specially. We may be able to tell that
1892 no exceptions propagate past this point. */
1894 this_may_throw = true;
1895 cleanup_gsi = gsi_start (cleanup_seq);
1896 stmt = gsi_stmt (cleanup_gsi);
1897 data->last_was_goto = false;
1899 switch (gimple_code (stmt))
1902 /* If the first element is a catch, they all must be. */
1903 while (!gsi_end_p (cleanup_gsi))
1905 stmt = gsi_stmt (cleanup_gsi);
1906 /* If we catch all exceptions, then the body does not
1907 propagate exceptions past this point. */
1908 if (gimple_catch_types (stmt) == NULL)
1909 this_may_throw = false;
1910 data->last_was_goto = false;
1911 handler_seq = gimple_catch_handler (stmt);
1912 handler_gsi = gsi_start (handler_seq);
1913 remove_useless_stmts_1 (&handler_gsi, data);
1914 gsi_next (&cleanup_gsi);
1919 case GIMPLE_EH_FILTER:
1920 /* If the first element is an eh_filter, it should stand alone. */
1921 if (gimple_eh_filter_must_not_throw (stmt))
1922 this_may_throw = false;
1923 else if (gimple_eh_filter_types (stmt) == NULL)
1924 this_may_throw = false;
1925 failure_seq = gimple_eh_filter_failure (stmt);
1926 failure_gsi = gsi_start (failure_seq);
1927 remove_useless_stmts_1 (&failure_gsi, data);
1932 /* Otherwise this is a list of cleanup statements. */
1933 remove_useless_stmts_1 (&cleanup_gsi, data);
1935 /* If the cleanup is empty, then we can emit the TRY block without
1936 the enclosing TRY_CATCH_EXPR. */
1937 if (gimple_seq_empty_p (cleanup_seq))
1939 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1940 gsi_remove(gsi, false);
1941 data->repeat = true;
1948 data->may_throw |= this_may_throw;
1951 /* Helper for remove_useless_stmts_1. Handle GIMPLE_BIND statements. */
1954 remove_useless_stmts_bind (gimple_stmt_iterator *gsi, struct rus_data *data ATTRIBUTE_UNUSED)
1957 gimple_seq body_seq, fn_body_seq;
1958 gimple_stmt_iterator body_gsi;
1960 gimple stmt = gsi_stmt (*gsi);
1962 /* First remove anything underneath the BIND_EXPR. */
1964 body_seq = gimple_bind_body (stmt);
1965 body_gsi = gsi_start (body_seq);
1966 remove_useless_stmts_1 (&body_gsi, data);
1968 /* If the GIMPLE_BIND has no variables, then we can pull everything
1969 up one level and remove the GIMPLE_BIND, unless this is the toplevel
1970 GIMPLE_BIND for the current function or an inlined function.
1972 When this situation occurs we will want to apply this
1973 optimization again. */
1974 block = gimple_bind_block (stmt);
1975 fn_body_seq = gimple_body (current_function_decl);
1976 if (gimple_bind_vars (stmt) == NULL_TREE
1977 && (gimple_seq_empty_p (fn_body_seq)
1978 || stmt != gimple_seq_first_stmt (fn_body_seq))
1980 || ! BLOCK_ABSTRACT_ORIGIN (block)
1981 || (TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block))
1984 tree var = NULL_TREE;
1985 /* Even if there are no gimple_bind_vars, there might be other
1986 decls in BLOCK_VARS rendering the GIMPLE_BIND not useless. */
1987 if (block && !BLOCK_NUM_NONLOCALIZED_VARS (block))
1988 for (var = BLOCK_VARS (block); var; var = TREE_CHAIN (var))
1989 if (TREE_CODE (var) == IMPORTED_DECL)
1991 if (var || (block && BLOCK_NUM_NONLOCALIZED_VARS (block)))
1995 gsi_insert_seq_before (gsi, body_seq, GSI_SAME_STMT);
1996 gsi_remove (gsi, false);
1997 data->repeat = true;
2004 /* Helper for remove_useless_stmts_1. Handle GIMPLE_GOTO statements. */
2007 remove_useless_stmts_goto (gimple_stmt_iterator *gsi, struct rus_data *data)
2009 gimple stmt = gsi_stmt (*gsi);
2011 tree dest = gimple_goto_dest (stmt);
2013 data->may_branch = true;
2014 data->last_was_goto = false;
2016 /* Record iterator for last goto expr, so that we can delete it if unnecessary. */
2017 if (TREE_CODE (dest) == LABEL_DECL)
2019 data->last_goto_gsi = *gsi;
2020 data->last_was_goto = true;
2026 /* Helper for remove_useless_stmts_1. Handle GIMPLE_LABEL statements. */
2029 remove_useless_stmts_label (gimple_stmt_iterator *gsi, struct rus_data *data)
2031 gimple stmt = gsi_stmt (*gsi);
2033 tree label = gimple_label_label (stmt);
2035 data->has_label = true;
2037 /* We do want to jump across non-local label receiver code. */
2038 if (DECL_NONLOCAL (label))
2039 data->last_was_goto = false;
2041 else if (data->last_was_goto
2042 && gimple_goto_dest (gsi_stmt (data->last_goto_gsi)) == label)
2044 /* Replace the preceding GIMPLE_GOTO statement with
2045 a GIMPLE_NOP, which will be subsequently removed.
2046 In this way, we avoid invalidating other iterators
2047 active on the statement sequence. */
2048 gsi_replace(&data->last_goto_gsi, gimple_build_nop(), false);
2049 data->last_was_goto = false;
2050 data->repeat = true;
2053 /* ??? Add something here to delete unused labels. */
2059 /* T is CALL_EXPR. Set current_function_calls_* flags. */
2062 notice_special_calls (gimple call)
2064 int flags = gimple_call_flags (call);
2066 if (flags & ECF_MAY_BE_ALLOCA)
2067 cfun->calls_alloca = true;
2068 if (flags & ECF_RETURNS_TWICE)
2069 cfun->calls_setjmp = true;
2073 /* Clear flags set by notice_special_calls. Used by dead code removal
2074 to update the flags. */
2077 clear_special_calls (void)
2079 cfun->calls_alloca = false;
2080 cfun->calls_setjmp = false;
2083 /* Remove useless statements from a statement sequence, and perform
2084 some preliminary simplifications. */
2087 remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *data)
2089 while (!gsi_end_p (*gsi))
2091 gimple stmt = gsi_stmt (*gsi);
2093 switch (gimple_code (stmt))
2096 remove_useless_stmts_cond (gsi, data);
2100 remove_useless_stmts_goto (gsi, data);
2104 remove_useless_stmts_label (gsi, data);
2109 stmt = gsi_stmt (*gsi);
2110 data->last_was_goto = false;
2111 if (stmt_could_throw_p (stmt))
2112 data->may_throw = true;
2118 data->last_was_goto = false;
2124 stmt = gsi_stmt (*gsi);
2125 data->last_was_goto = false;
2126 if (is_gimple_call (stmt))
2127 notice_special_calls (stmt);
2129 /* We used to call update_gimple_call_flags here,
2130 which copied side-effects and nothrows status
2131 from the function decl to the call. In the new
2132 tuplified GIMPLE, the accessors for this information
2133 always consult the function decl, so this copying
2134 is no longer necessary. */
2135 if (stmt_could_throw_p (stmt))
2136 data->may_throw = true;
2142 data->last_was_goto = false;
2143 data->may_branch = true;
2148 remove_useless_stmts_bind (gsi, data);
2152 if (gimple_try_kind (stmt) == GIMPLE_TRY_CATCH)
2153 remove_useless_stmts_tc (gsi, data);
2154 else if (gimple_try_kind (stmt) == GIMPLE_TRY_FINALLY)
2155 remove_useless_stmts_tf (gsi, data);
2165 gsi_remove (gsi, false);
2168 case GIMPLE_OMP_FOR:
2170 gimple_seq pre_body_seq = gimple_omp_for_pre_body (stmt);
2171 gimple_stmt_iterator pre_body_gsi = gsi_start (pre_body_seq);
2173 remove_useless_stmts_1 (&pre_body_gsi, data);
2174 data->last_was_goto = false;
2177 case GIMPLE_OMP_CRITICAL:
2178 case GIMPLE_OMP_CONTINUE:
2179 case GIMPLE_OMP_MASTER:
2180 case GIMPLE_OMP_ORDERED:
2181 case GIMPLE_OMP_SECTION:
2182 case GIMPLE_OMP_SECTIONS:
2183 case GIMPLE_OMP_SINGLE:
2185 gimple_seq body_seq = gimple_omp_body (stmt);
2186 gimple_stmt_iterator body_gsi = gsi_start (body_seq);
2188 remove_useless_stmts_1 (&body_gsi, data);
2189 data->last_was_goto = false;
2194 case GIMPLE_OMP_PARALLEL:
2195 case GIMPLE_OMP_TASK:
2197 /* Make sure the outermost GIMPLE_BIND isn't removed
2199 gimple_seq body_seq = gimple_omp_body (stmt);
2200 gimple bind = gimple_seq_first_stmt (body_seq);
2201 gimple_seq bind_seq = gimple_bind_body (bind);
2202 gimple_stmt_iterator bind_gsi = gsi_start (bind_seq);
2204 remove_useless_stmts_1 (&bind_gsi, data);
2205 data->last_was_goto = false;
2211 data->last_was_goto = false;
2218 /* Walk the function tree, removing useless statements and performing
2219 some preliminary simplifications. */
2222 remove_useless_stmts (void)
2224 struct rus_data data;
2226 clear_special_calls ();
2230 gimple_stmt_iterator gsi;
2232 gsi = gsi_start (gimple_body (current_function_decl));
2233 memset (&data, 0, sizeof (data));
2234 remove_useless_stmts_1 (&gsi, &data);
2236 while (data.repeat);
2238 #ifdef ENABLE_TYPES_CHECKING
2239 verify_types_in_gimple_seq (gimple_body (current_function_decl));
2246 struct gimple_opt_pass pass_remove_useless_stmts =
2250 "useless", /* name */
2252 remove_useless_stmts, /* execute */
2255 0, /* static_pass_number */
2256 TV_NONE, /* tv_id */
2257 PROP_gimple_any, /* properties_required */
2258 0, /* properties_provided */
2259 0, /* properties_destroyed */
2260 0, /* todo_flags_start */
2261 TODO_dump_func /* todo_flags_finish */
2265 /* Remove PHI nodes associated with basic block BB and all edges out of BB. */
2268 remove_phi_nodes_and_edges_for_unreachable_block (basic_block bb)
2270 /* Since this block is no longer reachable, we can just delete all
2271 of its PHI nodes. */
2272 remove_phi_nodes (bb);
2274 /* Remove edges to BB's successors. */
2275 while (EDGE_COUNT (bb->succs) > 0)
2276 remove_edge (EDGE_SUCC (bb, 0));
2280 /* Remove statements of basic block BB. */
2283 remove_bb (basic_block bb)
2285 gimple_stmt_iterator i;
2286 source_location loc = UNKNOWN_LOCATION;
2290 fprintf (dump_file, "Removing basic block %d\n", bb->index);
2291 if (dump_flags & TDF_DETAILS)
2293 dump_bb (bb, dump_file, 0);
2294 fprintf (dump_file, "\n");
2300 struct loop *loop = bb->loop_father;
2302 /* If a loop gets removed, clean up the information associated
2304 if (loop->latch == bb
2305 || loop->header == bb)
2306 free_numbers_of_iterations_estimates_loop (loop);
2309 /* Remove all the instructions in the block. */
2310 if (bb_seq (bb) != NULL)
2312 /* Walk backwards so as to get a chance to substitute all
2313 released DEFs into debug stmts. See
2314 eliminate_unnecessary_stmts() in tree-ssa-dce.c for more
2316 for (i = gsi_last_bb (bb); !gsi_end_p (i);)
2318 gimple stmt = gsi_stmt (i);
2319 if (gimple_code (stmt) == GIMPLE_LABEL
2320 && (FORCED_LABEL (gimple_label_label (stmt))
2321 || DECL_NONLOCAL (gimple_label_label (stmt))))
2324 gimple_stmt_iterator new_gsi;
2326 /* A non-reachable non-local label may still be referenced.
2327 But it no longer needs to carry the extra semantics of
2329 if (DECL_NONLOCAL (gimple_label_label (stmt)))
2331 DECL_NONLOCAL (gimple_label_label (stmt)) = 0;
2332 FORCED_LABEL (gimple_label_label (stmt)) = 1;
2335 new_bb = bb->prev_bb;
2336 new_gsi = gsi_start_bb (new_bb);
2337 gsi_remove (&i, false);
2338 gsi_insert_before (&new_gsi, stmt, GSI_NEW_STMT);
2342 /* Release SSA definitions if we are in SSA. Note that we
2343 may be called when not in SSA. For example,
2344 final_cleanup calls this function via
2345 cleanup_tree_cfg. */
2346 if (gimple_in_ssa_p (cfun))
2347 release_defs (stmt);
2349 gsi_remove (&i, true);
2353 i = gsi_last_bb (bb);
2357 /* Don't warn for removed gotos. Gotos are often removed due to
2358 jump threading, thus resulting in bogus warnings. Not great,
2359 since this way we lose warnings for gotos in the original
2360 program that are indeed unreachable. */
2361 if (gimple_code (stmt) != GIMPLE_GOTO
2362 && gimple_has_location (stmt))
2363 loc = gimple_location (stmt);
2367 /* If requested, give a warning that the first statement in the
2368 block is unreachable. We walk statements backwards in the
2369 loop above, so the last statement we process is the first statement
2371 if (loc > BUILTINS_LOCATION && LOCATION_LINE (loc) > 0)
2372 warning_at (loc, OPT_Wunreachable_code, "will never be executed");
2374 remove_phi_nodes_and_edges_for_unreachable_block (bb);
2375 bb->il.gimple = NULL;
2379 /* Given a basic block BB ending with COND_EXPR or SWITCH_EXPR, and a
2380 predicate VAL, return the edge that will be taken out of the block.
2381 If VAL does not match a unique edge, NULL is returned. */
2384 find_taken_edge (basic_block bb, tree val)
2388 stmt = last_stmt (bb);
2391 gcc_assert (is_ctrl_stmt (stmt));
2396 if (!is_gimple_min_invariant (val))
2399 if (gimple_code (stmt) == GIMPLE_COND)
2400 return find_taken_edge_cond_expr (bb, val);
2402 if (gimple_code (stmt) == GIMPLE_SWITCH)
2403 return find_taken_edge_switch_expr (bb, val);
2405 if (computed_goto_p (stmt))
2407 /* Only optimize if the argument is a label, if the argument is
2408 not a label then we can not construct a proper CFG.
2410 It may be the case that we only need to allow the LABEL_REF to
2411 appear inside an ADDR_EXPR, but we also allow the LABEL_REF to
2412 appear inside a LABEL_EXPR just to be safe. */
2413 if ((TREE_CODE (val) == ADDR_EXPR || TREE_CODE (val) == LABEL_EXPR)
2414 && TREE_CODE (TREE_OPERAND (val, 0)) == LABEL_DECL)
2415 return find_taken_edge_computed_goto (bb, TREE_OPERAND (val, 0));
2422 /* Given a constant value VAL and the entry block BB to a GOTO_EXPR
2423 statement, determine which of the outgoing edges will be taken out of the
2424 block. Return NULL if either edge may be taken. */
2427 find_taken_edge_computed_goto (basic_block bb, tree val)
2432 dest = label_to_block (val);
2435 e = find_edge (bb, dest);
2436 gcc_assert (e != NULL);
2442 /* Given a constant value VAL and the entry block BB to a COND_EXPR
2443 statement, determine which of the two edges will be taken out of the
2444 block. Return NULL if either edge may be taken. */
2447 find_taken_edge_cond_expr (basic_block bb, tree val)
2449 edge true_edge, false_edge;
2451 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
2453 gcc_assert (TREE_CODE (val) == INTEGER_CST);
2454 return (integer_zerop (val) ? false_edge : true_edge);
2457 /* Given an INTEGER_CST VAL and the entry block BB to a SWITCH_EXPR
2458 statement, determine which edge will be taken out of the block. Return
2459 NULL if any edge may be taken. */
2462 find_taken_edge_switch_expr (basic_block bb, tree val)
2464 basic_block dest_bb;
2469 switch_stmt = last_stmt (bb);
2470 taken_case = find_case_label_for_value (switch_stmt, val);
2471 dest_bb = label_to_block (CASE_LABEL (taken_case));
2473 e = find_edge (bb, dest_bb);
2479 /* Return the CASE_LABEL_EXPR that SWITCH_STMT will take for VAL.
2480 We can make optimal use here of the fact that the case labels are
2481 sorted: We can do a binary search for a case matching VAL. */
2484 find_case_label_for_value (gimple switch_stmt, tree val)
2486 size_t low, high, n = gimple_switch_num_labels (switch_stmt);
2487 tree default_case = gimple_switch_default_label (switch_stmt);
2489 for (low = 0, high = n; high - low > 1; )
2491 size_t i = (high + low) / 2;
2492 tree t = gimple_switch_label (switch_stmt, i);
2495 /* Cache the result of comparing CASE_LOW and val. */
2496 cmp = tree_int_cst_compare (CASE_LOW (t), val);
2503 if (CASE_HIGH (t) == NULL)
2505 /* A singe-valued case label. */
2511 /* A case range. We can only handle integer ranges. */
2512 if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
2517 return default_case;
2521 /* Dump a basic block on stderr. */
2524 gimple_debug_bb (basic_block bb)
2526 gimple_dump_bb (bb, stderr, 0, TDF_VOPS|TDF_MEMSYMS);
2530 /* Dump basic block with index N on stderr. */
2533 gimple_debug_bb_n (int n)
2535 gimple_debug_bb (BASIC_BLOCK (n));
2536 return BASIC_BLOCK (n);
2540 /* Dump the CFG on stderr.
2542 FLAGS are the same used by the tree dumping functions
2543 (see TDF_* in tree-pass.h). */
2546 gimple_debug_cfg (int flags)
2548 gimple_dump_cfg (stderr, flags);
2552 /* Dump the program showing basic block boundaries on the given FILE.
2554 FLAGS are the same used by the tree dumping functions (see TDF_* in
2558 gimple_dump_cfg (FILE *file, int flags)
2560 if (flags & TDF_DETAILS)
2562 const char *funcname
2563 = lang_hooks.decl_printable_name (current_function_decl, 2);
2566 fprintf (file, ";; Function %s\n\n", funcname);
2567 fprintf (file, ";; \n%d basic blocks, %d edges, last basic block %d.\n\n",
2568 n_basic_blocks, n_edges, last_basic_block);
2570 brief_dump_cfg (file);
2571 fprintf (file, "\n");
2574 if (flags & TDF_STATS)
2575 dump_cfg_stats (file);
2577 dump_function_to_file (current_function_decl, file, flags | TDF_BLOCKS);
2581 /* Dump CFG statistics on FILE. */
2584 dump_cfg_stats (FILE *file)
2586 static long max_num_merged_labels = 0;
2587 unsigned long size, total = 0;
2590 const char * const fmt_str = "%-30s%-13s%12s\n";
2591 const char * const fmt_str_1 = "%-30s%13d%11lu%c\n";
2592 const char * const fmt_str_2 = "%-30s%13ld%11lu%c\n";
2593 const char * const fmt_str_3 = "%-43s%11lu%c\n";
2594 const char *funcname
2595 = lang_hooks.decl_printable_name (current_function_decl, 2);
2598 fprintf (file, "\nCFG Statistics for %s\n\n", funcname);
2600 fprintf (file, "---------------------------------------------------------\n");
2601 fprintf (file, fmt_str, "", " Number of ", "Memory");
2602 fprintf (file, fmt_str, "", " instances ", "used ");
2603 fprintf (file, "---------------------------------------------------------\n");
2605 size = n_basic_blocks * sizeof (struct basic_block_def);
2607 fprintf (file, fmt_str_1, "Basic blocks", n_basic_blocks,
2608 SCALE (size), LABEL (size));
2612 num_edges += EDGE_COUNT (bb->succs);
2613 size = num_edges * sizeof (struct edge_def);
2615 fprintf (file, fmt_str_2, "Edges", num_edges, SCALE (size), LABEL (size));
2617 fprintf (file, "---------------------------------------------------------\n");
2618 fprintf (file, fmt_str_3, "Total memory used by CFG data", SCALE (total),
2620 fprintf (file, "---------------------------------------------------------\n");
2621 fprintf (file, "\n");
2623 if (cfg_stats.num_merged_labels > max_num_merged_labels)
2624 max_num_merged_labels = cfg_stats.num_merged_labels;
2626 fprintf (file, "Coalesced label blocks: %ld (Max so far: %ld)\n",
2627 cfg_stats.num_merged_labels, max_num_merged_labels);
2629 fprintf (file, "\n");
2633 /* Dump CFG statistics on stderr. Keep extern so that it's always
2634 linked in the final executable. */
2637 debug_cfg_stats (void)
2639 dump_cfg_stats (stderr);
2643 /* Dump the flowgraph to a .vcg FILE. */
2646 gimple_cfg2vcg (FILE *file)
2651 const char *funcname
2652 = lang_hooks.decl_printable_name (current_function_decl, 2);
2654 /* Write the file header. */
2655 fprintf (file, "graph: { title: \"%s\"\n", funcname);
2656 fprintf (file, "node: { title: \"ENTRY\" label: \"ENTRY\" }\n");
2657 fprintf (file, "node: { title: \"EXIT\" label: \"EXIT\" }\n");
2659 /* Write blocks and edges. */
2660 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
2662 fprintf (file, "edge: { sourcename: \"ENTRY\" targetname: \"%d\"",
2665 if (e->flags & EDGE_FAKE)
2666 fprintf (file, " linestyle: dotted priority: 10");
2668 fprintf (file, " linestyle: solid priority: 100");
2670 fprintf (file, " }\n");
2676 enum gimple_code head_code, end_code;
2677 const char *head_name, *end_name;
2680 gimple first = first_stmt (bb);
2681 gimple last = last_stmt (bb);
2685 head_code = gimple_code (first);
2686 head_name = gimple_code_name[head_code];
2687 head_line = get_lineno (first);
2690 head_name = "no-statement";
2694 end_code = gimple_code (last);
2695 end_name = gimple_code_name[end_code];
2696 end_line = get_lineno (last);
2699 end_name = "no-statement";
2701 fprintf (file, "node: { title: \"%d\" label: \"#%d\\n%s (%d)\\n%s (%d)\"}\n",
2702 bb->index, bb->index, head_name, head_line, end_name,
2705 FOR_EACH_EDGE (e, ei, bb->succs)
2707 if (e->dest == EXIT_BLOCK_PTR)
2708 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"EXIT\"", bb->index);
2710 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"%d\"", bb->index, e->dest->index);
2712 if (e->flags & EDGE_FAKE)
2713 fprintf (file, " priority: 10 linestyle: dotted");
2715 fprintf (file, " priority: 100 linestyle: solid");
2717 fprintf (file, " }\n");
2720 if (bb->next_bb != EXIT_BLOCK_PTR)
2724 fputs ("}\n\n", file);
2729 /*---------------------------------------------------------------------------
2730 Miscellaneous helpers
2731 ---------------------------------------------------------------------------*/
2733 /* Return true if T represents a stmt that always transfers control. */
2736 is_ctrl_stmt (gimple t)
2738 switch (gimple_code (t))
2752 /* Return true if T is a statement that may alter the flow of control
2753 (e.g., a call to a non-returning function). */
2756 is_ctrl_altering_stmt (gimple t)
2760 switch (gimple_code (t))
2764 int flags = gimple_call_flags (t);
2766 /* A non-pure/const call alters flow control if the current
2767 function has nonlocal labels. */
2768 if (!(flags & (ECF_CONST | ECF_PURE)) && cfun->has_nonlocal_label)
2771 /* A call also alters control flow if it does not return. */
2772 if (gimple_call_flags (t) & ECF_NORETURN)
2778 /* OpenMP directives alter control flow. */
2785 /* If a statement can throw, it alters control flow. */
2786 return stmt_can_throw_internal (t);
2790 /* Return true if T is a simple local goto. */
2793 simple_goto_p (gimple t)
2795 return (gimple_code (t) == GIMPLE_GOTO
2796 && TREE_CODE (gimple_goto_dest (t)) == LABEL_DECL);
2800 /* Return true if T can make an abnormal transfer of control flow.
2801 Transfers of control flow associated with EH are excluded. */
2804 stmt_can_make_abnormal_goto (gimple t)
2806 if (computed_goto_p (t))
2808 if (is_gimple_call (t))
2809 return gimple_has_side_effects (t) && cfun->has_nonlocal_label;
2814 /* Return true if STMT should start a new basic block. PREV_STMT is
2815 the statement preceding STMT. It is used when STMT is a label or a
2816 case label. Labels should only start a new basic block if their
2817 previous statement wasn't a label. Otherwise, sequence of labels
2818 would generate unnecessary basic blocks that only contain a single
2822 stmt_starts_bb_p (gimple stmt, gimple prev_stmt)
2827 /* Labels start a new basic block only if the preceding statement
2828 wasn't a label of the same type. This prevents the creation of
2829 consecutive blocks that have nothing but a single label. */
2830 if (gimple_code (stmt) == GIMPLE_LABEL)
2832 /* Nonlocal and computed GOTO targets always start a new block. */
2833 if (DECL_NONLOCAL (gimple_label_label (stmt))
2834 || FORCED_LABEL (gimple_label_label (stmt)))
2837 if (prev_stmt && gimple_code (prev_stmt) == GIMPLE_LABEL)
2839 if (DECL_NONLOCAL (gimple_label_label (prev_stmt)))
2842 cfg_stats.num_merged_labels++;
2853 /* Return true if T should end a basic block. */
2856 stmt_ends_bb_p (gimple t)
2858 return is_ctrl_stmt (t) || is_ctrl_altering_stmt (t);
2861 /* Remove block annotations and other data structures. */
2864 delete_tree_cfg_annotations (void)
2866 label_to_block_map = NULL;
2870 /* Return the first statement in basic block BB. */
2873 first_stmt (basic_block bb)
2875 gimple_stmt_iterator i = gsi_start_bb (bb);
2878 while (!gsi_end_p (i) && is_gimple_debug ((stmt = gsi_stmt (i))))
2886 /* Return the first non-label statement in basic block BB. */
2889 first_non_label_stmt (basic_block bb)
2891 gimple_stmt_iterator i = gsi_start_bb (bb);
2892 while (!gsi_end_p (i) && gimple_code (gsi_stmt (i)) == GIMPLE_LABEL)
2894 return !gsi_end_p (i) ? gsi_stmt (i) : NULL;
2897 /* Return the last statement in basic block BB. */
2900 last_stmt (basic_block bb)
2902 gimple_stmt_iterator i = gsi_last_bb (bb);
2905 while (!gsi_end_p (i) && is_gimple_debug ((stmt = gsi_stmt (i))))
2913 /* Return the last statement of an otherwise empty block. Return NULL
2914 if the block is totally empty, or if it contains more than one
2918 last_and_only_stmt (basic_block bb)
2920 gimple_stmt_iterator i = gsi_last_nondebug_bb (bb);
2926 last = gsi_stmt (i);
2927 gsi_prev_nondebug (&i);
2931 /* Empty statements should no longer appear in the instruction stream.
2932 Everything that might have appeared before should be deleted by
2933 remove_useless_stmts, and the optimizers should just gsi_remove
2934 instead of smashing with build_empty_stmt.
2936 Thus the only thing that should appear here in a block containing
2937 one executable statement is a label. */
2938 prev = gsi_stmt (i);
2939 if (gimple_code (prev) == GIMPLE_LABEL)
2945 /* Reinstall those PHI arguments queued in OLD_EDGE to NEW_EDGE. */
2948 reinstall_phi_args (edge new_edge, edge old_edge)
2950 edge_var_map_vector v;
2953 gimple_stmt_iterator phis;
2955 v = redirect_edge_var_map_vector (old_edge);
2959 for (i = 0, phis = gsi_start_phis (new_edge->dest);
2960 VEC_iterate (edge_var_map, v, i, vm) && !gsi_end_p (phis);
2961 i++, gsi_next (&phis))
2963 gimple phi = gsi_stmt (phis);
2964 tree result = redirect_edge_var_map_result (vm);
2965 tree arg = redirect_edge_var_map_def (vm);
2967 gcc_assert (result == gimple_phi_result (phi));
2969 add_phi_arg (phi, arg, new_edge, redirect_edge_var_map_location (vm));
2972 redirect_edge_var_map_clear (old_edge);
2975 /* Returns the basic block after which the new basic block created
2976 by splitting edge EDGE_IN should be placed. Tries to keep the new block
2977 near its "logical" location. This is of most help to humans looking
2978 at debugging dumps. */
2981 split_edge_bb_loc (edge edge_in)
2983 basic_block dest = edge_in->dest;
2984 basic_block dest_prev = dest->prev_bb;
2988 edge e = find_edge (dest_prev, dest);
2989 if (e && !(e->flags & EDGE_COMPLEX))
2990 return edge_in->src;
2995 /* Split a (typically critical) edge EDGE_IN. Return the new block.
2996 Abort on abnormal edges. */
2999 gimple_split_edge (edge edge_in)
3001 basic_block new_bb, after_bb, dest;
3004 /* Abnormal edges cannot be split. */
3005 gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
3007 dest = edge_in->dest;
3009 after_bb = split_edge_bb_loc (edge_in);
3011 new_bb = create_empty_bb (after_bb);
3012 new_bb->frequency = EDGE_FREQUENCY (edge_in);
3013 new_bb->count = edge_in->count;
3014 new_edge = make_edge (new_bb, dest, EDGE_FALLTHRU);
3015 new_edge->probability = REG_BR_PROB_BASE;
3016 new_edge->count = edge_in->count;
3018 e = redirect_edge_and_branch (edge_in, new_bb);
3019 gcc_assert (e == edge_in);
3020 reinstall_phi_args (new_edge, e);
3025 /* Callback for walk_tree, check that all elements with address taken are
3026 properly noticed as such. The DATA is an int* that is 1 if TP was seen
3027 inside a PHI node. */
3030 verify_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
3037 /* Check operand N for being valid GIMPLE and give error MSG if not. */
3038 #define CHECK_OP(N, MSG) \
3039 do { if (!is_gimple_val (TREE_OPERAND (t, N))) \
3040 { error (MSG); return TREE_OPERAND (t, N); }} while (0)
3042 switch (TREE_CODE (t))
3045 if (SSA_NAME_IN_FREE_LIST (t))
3047 error ("SSA name in freelist but still referenced");
3053 x = TREE_OPERAND (t, 0);
3054 if (!is_gimple_reg (x) && !is_gimple_min_invariant (x))
3056 error ("Indirect reference's operand is not a register or a constant.");
3062 x = fold (ASSERT_EXPR_COND (t));
3063 if (x == boolean_false_node)
3065 error ("ASSERT_EXPR with an always-false condition");
3071 error ("MODIFY_EXPR not expected while having tuples.");
3077 bool old_side_effects;
3079 bool new_side_effects;
3081 gcc_assert (is_gimple_address (t));
3083 old_constant = TREE_CONSTANT (t);
3084 old_side_effects = TREE_SIDE_EFFECTS (t);
3086 recompute_tree_invariant_for_addr_expr (t);
3087 new_side_effects = TREE_SIDE_EFFECTS (t);
3088 new_constant = TREE_CONSTANT (t);
3090 if (old_constant != new_constant)
3092 error ("constant not recomputed when ADDR_EXPR changed");
3095 if (old_side_effects != new_side_effects)
3097 error ("side effects not recomputed when ADDR_EXPR changed");
3101 /* Skip any references (they will be checked when we recurse down the
3102 tree) and ensure that any variable used as a prefix is marked
3104 for (x = TREE_OPERAND (t, 0);
3105 handled_component_p (x);
3106 x = TREE_OPERAND (x, 0))
3109 if (!(TREE_CODE (x) == VAR_DECL
3110 || TREE_CODE (x) == PARM_DECL
3111 || TREE_CODE (x) == RESULT_DECL))
3113 if (!TREE_ADDRESSABLE (x))
3115 error ("address taken, but ADDRESSABLE bit not set");
3118 if (DECL_GIMPLE_REG_P (x))
3120 error ("DECL_GIMPLE_REG_P set on a variable with address taken");
3128 x = COND_EXPR_COND (t);
3129 if (!INTEGRAL_TYPE_P (TREE_TYPE (x)))
3131 error ("non-integral used in condition");
3134 if (!is_gimple_condexpr (x))
3136 error ("invalid conditional operand");
3141 case NON_LVALUE_EXPR:
3145 case FIX_TRUNC_EXPR:
3150 case TRUTH_NOT_EXPR:
3151 CHECK_OP (0, "invalid operand to unary operator");
3158 case ARRAY_RANGE_REF:
3160 case VIEW_CONVERT_EXPR:
3161 /* We have a nest of references. Verify that each of the operands
3162 that determine where to reference is either a constant or a variable,
3163 verify that the base is valid, and then show we've already checked
3165 while (handled_component_p (t))
3167 if (TREE_CODE (t) == COMPONENT_REF && TREE_OPERAND (t, 2))
3168 CHECK_OP (2, "invalid COMPONENT_REF offset operator");
3169 else if (TREE_CODE (t) == ARRAY_REF
3170 || TREE_CODE (t) == ARRAY_RANGE_REF)
3172 CHECK_OP (1, "invalid array index");
3173 if (TREE_OPERAND (t, 2))
3174 CHECK_OP (2, "invalid array lower bound");
3175 if (TREE_OPERAND (t, 3))
3176 CHECK_OP (3, "invalid array stride");
3178 else if (TREE_CODE (t) == BIT_FIELD_REF)
3180 if (!host_integerp (TREE_OPERAND (t, 1), 1)
3181 || !host_integerp (TREE_OPERAND (t, 2), 1))
3183 error ("invalid position or size operand to BIT_FIELD_REF");
3186 else if (INTEGRAL_TYPE_P (TREE_TYPE (t))
3187 && (TYPE_PRECISION (TREE_TYPE (t))
3188 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
3190 error ("integral result type precision does not match "
3191 "field size of BIT_FIELD_REF");
3194 if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
3195 && (GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (t)))
3196 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
3198 error ("mode precision of non-integral result does not "
3199 "match field size of BIT_FIELD_REF");
3204 t = TREE_OPERAND (t, 0);
3207 if (!is_gimple_min_invariant (t) && !is_gimple_lvalue (t))
3209 error ("invalid reference prefix");
3216 /* PLUS_EXPR and MINUS_EXPR don't work on pointers, they should be done using
3217 POINTER_PLUS_EXPR. */
3218 if (POINTER_TYPE_P (TREE_TYPE (t)))
3220 error ("invalid operand to plus/minus, type is a pointer");
3223 CHECK_OP (0, "invalid operand to binary operator");
3224 CHECK_OP (1, "invalid operand to binary operator");
3227 case POINTER_PLUS_EXPR:
3228 /* Check to make sure the first operand is a pointer or reference type. */
3229 if (!POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 0))))
3231 error ("invalid operand to pointer plus, first operand is not a pointer");
3234 /* Check to make sure the second operand is an integer with type of
3236 if (!useless_type_conversion_p (sizetype,
3237 TREE_TYPE (TREE_OPERAND (t, 1))))
3239 error ("invalid operand to pointer plus, second operand is not an "
3240 "integer with type of sizetype.");
3250 case UNORDERED_EXPR:
3259 case TRUNC_DIV_EXPR:
3261 case FLOOR_DIV_EXPR:
3262 case ROUND_DIV_EXPR:
3263 case TRUNC_MOD_EXPR:
3265 case FLOOR_MOD_EXPR:
3266 case ROUND_MOD_EXPR:
3268 case EXACT_DIV_EXPR:
3278 CHECK_OP (0, "invalid operand to binary operator");
3279 CHECK_OP (1, "invalid operand to binary operator");
3283 if (TREE_CONSTANT (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
3296 /* Verify if EXPR is either a GIMPLE ID or a GIMPLE indirect reference.
3297 Returns true if there is an error, otherwise false. */
3300 verify_types_in_gimple_min_lval (tree expr)
3304 if (is_gimple_id (expr))
3307 if (!INDIRECT_REF_P (expr)
3308 && TREE_CODE (expr) != TARGET_MEM_REF)
3310 error ("invalid expression for min lvalue");
3314 /* TARGET_MEM_REFs are strange beasts. */
3315 if (TREE_CODE (expr) == TARGET_MEM_REF)
3318 op = TREE_OPERAND (expr, 0);
3319 if (!is_gimple_val (op))
3321 error ("invalid operand in indirect reference");
3322 debug_generic_stmt (op);
3325 if (!useless_type_conversion_p (TREE_TYPE (expr),
3326 TREE_TYPE (TREE_TYPE (op))))
3328 error ("type mismatch in indirect reference");
3329 debug_generic_stmt (TREE_TYPE (expr));
3330 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3337 /* Verify if EXPR is a valid GIMPLE reference expression. If
3338 REQUIRE_LVALUE is true verifies it is an lvalue. Returns true
3339 if there is an error, otherwise false. */
3342 verify_types_in_gimple_reference (tree expr, bool require_lvalue)
3344 while (handled_component_p (expr))
3346 tree op = TREE_OPERAND (expr, 0);
3348 if (TREE_CODE (expr) == ARRAY_REF
3349 || TREE_CODE (expr) == ARRAY_RANGE_REF)
3351 if (!is_gimple_val (TREE_OPERAND (expr, 1))
3352 || (TREE_OPERAND (expr, 2)
3353 && !is_gimple_val (TREE_OPERAND (expr, 2)))
3354 || (TREE_OPERAND (expr, 3)
3355 && !is_gimple_val (TREE_OPERAND (expr, 3))))
3357 error ("invalid operands to array reference");
3358 debug_generic_stmt (expr);
3363 /* Verify if the reference array element types are compatible. */
3364 if (TREE_CODE (expr) == ARRAY_REF
3365 && !useless_type_conversion_p (TREE_TYPE (expr),
3366 TREE_TYPE (TREE_TYPE (op))))
3368 error ("type mismatch in array reference");
3369 debug_generic_stmt (TREE_TYPE (expr));
3370 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3373 if (TREE_CODE (expr) == ARRAY_RANGE_REF
3374 && !useless_type_conversion_p (TREE_TYPE (TREE_TYPE (expr)),
3375 TREE_TYPE (TREE_TYPE (op))))
3377 error ("type mismatch in array range reference");
3378 debug_generic_stmt (TREE_TYPE (TREE_TYPE (expr)));
3379 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3383 if ((TREE_CODE (expr) == REALPART_EXPR
3384 || TREE_CODE (expr) == IMAGPART_EXPR)
3385 && !useless_type_conversion_p (TREE_TYPE (expr),
3386 TREE_TYPE (TREE_TYPE (op))))
3388 error ("type mismatch in real/imagpart reference");
3389 debug_generic_stmt (TREE_TYPE (expr));
3390 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3394 if (TREE_CODE (expr) == COMPONENT_REF
3395 && !useless_type_conversion_p (TREE_TYPE (expr),
3396 TREE_TYPE (TREE_OPERAND (expr, 1))))
3398 error ("type mismatch in component reference");
3399 debug_generic_stmt (TREE_TYPE (expr));
3400 debug_generic_stmt (TREE_TYPE (TREE_OPERAND (expr, 1)));
3404 /* For VIEW_CONVERT_EXPRs which are allowed here, too, there
3405 is nothing to verify. Gross mismatches at most invoke
3406 undefined behavior. */
3407 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR
3408 && !handled_component_p (op))
3414 return ((require_lvalue || !is_gimple_min_invariant (expr))
3415 && verify_types_in_gimple_min_lval (expr));
3418 /* Returns true if there is one pointer type in TYPE_POINTER_TO (SRC_OBJ)
3419 list of pointer-to types that is trivially convertible to DEST. */
3422 one_pointer_to_useless_type_conversion_p (tree dest, tree src_obj)
3426 if (!TYPE_POINTER_TO (src_obj))
3429 for (src = TYPE_POINTER_TO (src_obj); src; src = TYPE_NEXT_PTR_TO (src))
3430 if (useless_type_conversion_p (dest, src))
3436 /* Return true if TYPE1 is a fixed-point type and if conversions to and
3437 from TYPE2 can be handled by FIXED_CONVERT_EXPR. */
3440 valid_fixed_convert_types_p (tree type1, tree type2)
3442 return (FIXED_POINT_TYPE_P (type1)
3443 && (INTEGRAL_TYPE_P (type2)
3444 || SCALAR_FLOAT_TYPE_P (type2)
3445 || FIXED_POINT_TYPE_P (type2)));
3448 /* Verify the contents of a GIMPLE_CALL STMT. Returns true when there
3449 is a problem, otherwise false. */
3452 verify_gimple_call (gimple stmt)
3454 tree fn = gimple_call_fn (stmt);
3457 if (!POINTER_TYPE_P (TREE_TYPE (fn))
3458 || (TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != FUNCTION_TYPE
3459 && TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != METHOD_TYPE))
3461 error ("non-function in gimple call");
3465 if (gimple_call_lhs (stmt)
3466 && !is_gimple_lvalue (gimple_call_lhs (stmt)))
3468 error ("invalid LHS in gimple call");
3472 fntype = TREE_TYPE (TREE_TYPE (fn));
3473 if (gimple_call_lhs (stmt)
3474 && !useless_type_conversion_p (TREE_TYPE (gimple_call_lhs (stmt)),
3476 /* ??? At least C++ misses conversions at assignments from
3477 void * call results.
3478 ??? Java is completely off. Especially with functions
3479 returning java.lang.Object.
3480 For now simply allow arbitrary pointer type conversions. */
3481 && !(POINTER_TYPE_P (TREE_TYPE (gimple_call_lhs (stmt)))
3482 && POINTER_TYPE_P (TREE_TYPE (fntype))))
3484 error ("invalid conversion in gimple call");
3485 debug_generic_stmt (TREE_TYPE (gimple_call_lhs (stmt)));
3486 debug_generic_stmt (TREE_TYPE (fntype));
3490 /* ??? The C frontend passes unpromoted arguments in case it
3491 didn't see a function declaration before the call. So for now
3492 leave the call arguments unverified. Once we gimplify
3493 unit-at-a-time we have a chance to fix this. */
3498 /* Verifies the gimple comparison with the result type TYPE and
3499 the operands OP0 and OP1. */
3502 verify_gimple_comparison (tree type, tree op0, tree op1)
3504 tree op0_type = TREE_TYPE (op0);
3505 tree op1_type = TREE_TYPE (op1);
3507 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3509 error ("invalid operands in gimple comparison");
3513 /* For comparisons we do not have the operations type as the
3514 effective type the comparison is carried out in. Instead
3515 we require that either the first operand is trivially
3516 convertible into the second, or the other way around.
3517 The resulting type of a comparison may be any integral type.
3518 Because we special-case pointers to void we allow
3519 comparisons of pointers with the same mode as well. */
3520 if ((!useless_type_conversion_p (op0_type, op1_type)
3521 && !useless_type_conversion_p (op1_type, op0_type)
3522 && (!POINTER_TYPE_P (op0_type)
3523 || !POINTER_TYPE_P (op1_type)
3524 || TYPE_MODE (op0_type) != TYPE_MODE (op1_type)))
3525 || !INTEGRAL_TYPE_P (type))
3527 error ("type mismatch in comparison expression");
3528 debug_generic_expr (type);
3529 debug_generic_expr (op0_type);
3530 debug_generic_expr (op1_type);
3537 /* Verify a gimple assignment statement STMT with an unary rhs.
3538 Returns true if anything is wrong. */
3541 verify_gimple_assign_unary (gimple stmt)
3543 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3544 tree lhs = gimple_assign_lhs (stmt);
3545 tree lhs_type = TREE_TYPE (lhs);
3546 tree rhs1 = gimple_assign_rhs1 (stmt);
3547 tree rhs1_type = TREE_TYPE (rhs1);
3549 if (!is_gimple_reg (lhs)
3551 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3553 error ("non-register as LHS of unary operation");
3557 if (!is_gimple_val (rhs1))
3559 error ("invalid operand in unary operation");
3563 /* First handle conversions. */
3568 /* Allow conversions between integral types and pointers only if
3569 there is no sign or zero extension involved.
3570 For targets were the precision of sizetype doesn't match that
3571 of pointers we need to allow arbitrary conversions from and
3573 if ((POINTER_TYPE_P (lhs_type)
3574 && INTEGRAL_TYPE_P (rhs1_type)
3575 && (TYPE_PRECISION (lhs_type) >= TYPE_PRECISION (rhs1_type)
3576 || rhs1_type == sizetype))
3577 || (POINTER_TYPE_P (rhs1_type)
3578 && INTEGRAL_TYPE_P (lhs_type)
3579 && (TYPE_PRECISION (rhs1_type) >= TYPE_PRECISION (lhs_type)
3580 || lhs_type == sizetype)))
3583 /* Allow conversion from integer to offset type and vice versa. */
3584 if ((TREE_CODE (lhs_type) == OFFSET_TYPE
3585 && TREE_CODE (rhs1_type) == INTEGER_TYPE)
3586 || (TREE_CODE (lhs_type) == INTEGER_TYPE
3587 && TREE_CODE (rhs1_type) == OFFSET_TYPE))
3590 /* Otherwise assert we are converting between types of the
3592 if (INTEGRAL_TYPE_P (lhs_type) != INTEGRAL_TYPE_P (rhs1_type))
3594 error ("invalid types in nop conversion");
3595 debug_generic_expr (lhs_type);
3596 debug_generic_expr (rhs1_type);
3603 case FIXED_CONVERT_EXPR:
3605 if (!valid_fixed_convert_types_p (lhs_type, rhs1_type)
3606 && !valid_fixed_convert_types_p (rhs1_type, lhs_type))
3608 error ("invalid types in fixed-point conversion");
3609 debug_generic_expr (lhs_type);
3610 debug_generic_expr (rhs1_type);
3619 if (!INTEGRAL_TYPE_P (rhs1_type) || !SCALAR_FLOAT_TYPE_P (lhs_type))
3621 error ("invalid types in conversion to floating point");
3622 debug_generic_expr (lhs_type);
3623 debug_generic_expr (rhs1_type);
3630 case FIX_TRUNC_EXPR:
3632 if (!INTEGRAL_TYPE_P (lhs_type) || !SCALAR_FLOAT_TYPE_P (rhs1_type))
3634 error ("invalid types in conversion to integer");
3635 debug_generic_expr (lhs_type);
3636 debug_generic_expr (rhs1_type);
3643 case VEC_UNPACK_HI_EXPR:
3644 case VEC_UNPACK_LO_EXPR:
3645 case REDUC_MAX_EXPR:
3646 case REDUC_MIN_EXPR:
3647 case REDUC_PLUS_EXPR:
3648 case VEC_UNPACK_FLOAT_HI_EXPR:
3649 case VEC_UNPACK_FLOAT_LO_EXPR:
3653 case TRUTH_NOT_EXPR:
3658 case NON_LVALUE_EXPR:
3666 /* For the remaining codes assert there is no conversion involved. */
3667 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3669 error ("non-trivial conversion in unary operation");
3670 debug_generic_expr (lhs_type);
3671 debug_generic_expr (rhs1_type);
3678 /* Verify a gimple assignment statement STMT with a binary rhs.
3679 Returns true if anything is wrong. */
3682 verify_gimple_assign_binary (gimple stmt)
3684 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3685 tree lhs = gimple_assign_lhs (stmt);
3686 tree lhs_type = TREE_TYPE (lhs);
3687 tree rhs1 = gimple_assign_rhs1 (stmt);
3688 tree rhs1_type = TREE_TYPE (rhs1);
3689 tree rhs2 = gimple_assign_rhs2 (stmt);
3690 tree rhs2_type = TREE_TYPE (rhs2);
3692 if (!is_gimple_reg (lhs)
3694 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3696 error ("non-register as LHS of binary operation");
3700 if (!is_gimple_val (rhs1)
3701 || !is_gimple_val (rhs2))
3703 error ("invalid operands in binary operation");
3707 /* First handle operations that involve different types. */
3712 if (TREE_CODE (lhs_type) != COMPLEX_TYPE
3713 || !(INTEGRAL_TYPE_P (rhs1_type)
3714 || SCALAR_FLOAT_TYPE_P (rhs1_type))
3715 || !(INTEGRAL_TYPE_P (rhs2_type)
3716 || SCALAR_FLOAT_TYPE_P (rhs2_type)))
3718 error ("type mismatch in complex expression");
3719 debug_generic_expr (lhs_type);
3720 debug_generic_expr (rhs1_type);
3721 debug_generic_expr (rhs2_type);
3733 /* Shifts and rotates are ok on integral types, fixed point
3734 types and integer vector types. */
3735 if ((!INTEGRAL_TYPE_P (rhs1_type)
3736 && !FIXED_POINT_TYPE_P (rhs1_type)
3737 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3738 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE))
3739 || (!INTEGRAL_TYPE_P (rhs2_type)
3740 /* Vector shifts of vectors are also ok. */
3741 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3742 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE
3743 && TREE_CODE (rhs2_type) == VECTOR_TYPE
3744 && TREE_CODE (TREE_TYPE (rhs2_type)) == INTEGER_TYPE))
3745 || !useless_type_conversion_p (lhs_type, rhs1_type))
3747 error ("type mismatch in shift expression");
3748 debug_generic_expr (lhs_type);
3749 debug_generic_expr (rhs1_type);
3750 debug_generic_expr (rhs2_type);
3757 case VEC_LSHIFT_EXPR:
3758 case VEC_RSHIFT_EXPR:
3760 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3761 || !(INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))
3762 || FIXED_POINT_TYPE_P (TREE_TYPE (rhs1_type))
3763 || SCALAR_FLOAT_TYPE_P (TREE_TYPE (rhs1_type)))
3764 || (!INTEGRAL_TYPE_P (rhs2_type)
3765 && (TREE_CODE (rhs2_type) != VECTOR_TYPE
3766 || !INTEGRAL_TYPE_P (TREE_TYPE (rhs2_type))))
3767 || !useless_type_conversion_p (lhs_type, rhs1_type))
3769 error ("type mismatch in vector shift expression");
3770 debug_generic_expr (lhs_type);
3771 debug_generic_expr (rhs1_type);
3772 debug_generic_expr (rhs2_type);
3775 /* For shifting a vector of floating point components we
3776 only allow shifting by a constant multiple of the element size. */
3777 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (rhs1_type))
3778 && (TREE_CODE (rhs2) != INTEGER_CST
3779 || !div_if_zero_remainder (EXACT_DIV_EXPR, rhs2,
3780 TYPE_SIZE (TREE_TYPE (rhs1_type)))))
3782 error ("non-element sized vector shift of floating point vector");
3791 /* We use regular PLUS_EXPR for vectors.
3792 ??? This just makes the checker happy and may not be what is
3794 if (TREE_CODE (lhs_type) == VECTOR_TYPE
3795 && POINTER_TYPE_P (TREE_TYPE (lhs_type)))
3797 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3798 || TREE_CODE (rhs2_type) != VECTOR_TYPE)
3800 error ("invalid non-vector operands to vector valued plus");
3803 lhs_type = TREE_TYPE (lhs_type);
3804 rhs1_type = TREE_TYPE (rhs1_type);
3805 rhs2_type = TREE_TYPE (rhs2_type);
3806 /* PLUS_EXPR is commutative, so we might end up canonicalizing
3807 the pointer to 2nd place. */
3808 if (POINTER_TYPE_P (rhs2_type))
3810 tree tem = rhs1_type;
3811 rhs1_type = rhs2_type;
3814 goto do_pointer_plus_expr_check;
3820 if (POINTER_TYPE_P (lhs_type)
3821 || POINTER_TYPE_P (rhs1_type)
3822 || POINTER_TYPE_P (rhs2_type))
3824 error ("invalid (pointer) operands to plus/minus");
3828 /* Continue with generic binary expression handling. */
3832 case POINTER_PLUS_EXPR:
3834 do_pointer_plus_expr_check:
3835 if (!POINTER_TYPE_P (rhs1_type)
3836 || !useless_type_conversion_p (lhs_type, rhs1_type)
3837 || !useless_type_conversion_p (sizetype, rhs2_type))
3839 error ("type mismatch in pointer plus expression");
3840 debug_generic_stmt (lhs_type);
3841 debug_generic_stmt (rhs1_type);
3842 debug_generic_stmt (rhs2_type);
3849 case TRUTH_ANDIF_EXPR:
3850 case TRUTH_ORIF_EXPR:
3853 case TRUTH_AND_EXPR:
3855 case TRUTH_XOR_EXPR:
3857 /* We allow any kind of integral typed argument and result. */
3858 if (!INTEGRAL_TYPE_P (rhs1_type)
3859 || !INTEGRAL_TYPE_P (rhs2_type)
3860 || !INTEGRAL_TYPE_P (lhs_type))
3862 error ("type mismatch in binary truth expression");
3863 debug_generic_expr (lhs_type);
3864 debug_generic_expr (rhs1_type);
3865 debug_generic_expr (rhs2_type);
3878 case UNORDERED_EXPR:
3886 /* Comparisons are also binary, but the result type is not
3887 connected to the operand types. */
3888 return verify_gimple_comparison (lhs_type, rhs1, rhs2);
3890 case WIDEN_SUM_EXPR:
3891 case WIDEN_MULT_EXPR:
3892 case VEC_WIDEN_MULT_HI_EXPR:
3893 case VEC_WIDEN_MULT_LO_EXPR:
3894 case VEC_PACK_TRUNC_EXPR:
3895 case VEC_PACK_SAT_EXPR:
3896 case VEC_PACK_FIX_TRUNC_EXPR:
3897 case VEC_EXTRACT_EVEN_EXPR:
3898 case VEC_EXTRACT_ODD_EXPR:
3899 case VEC_INTERLEAVE_HIGH_EXPR:
3900 case VEC_INTERLEAVE_LOW_EXPR:
3905 case TRUNC_DIV_EXPR:
3907 case FLOOR_DIV_EXPR:
3908 case ROUND_DIV_EXPR:
3909 case TRUNC_MOD_EXPR:
3911 case FLOOR_MOD_EXPR:
3912 case ROUND_MOD_EXPR:
3914 case EXACT_DIV_EXPR:
3920 /* Continue with generic binary expression handling. */
3927 if (!useless_type_conversion_p (lhs_type, rhs1_type)
3928 || !useless_type_conversion_p (lhs_type, rhs2_type))
3930 error ("type mismatch in binary expression");
3931 debug_generic_stmt (lhs_type);
3932 debug_generic_stmt (rhs1_type);
3933 debug_generic_stmt (rhs2_type);
3940 /* Verify a gimple assignment statement STMT with a single rhs.
3941 Returns true if anything is wrong. */
3944 verify_gimple_assign_single (gimple stmt)
3946 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3947 tree lhs = gimple_assign_lhs (stmt);
3948 tree lhs_type = TREE_TYPE (lhs);
3949 tree rhs1 = gimple_assign_rhs1 (stmt);
3950 tree rhs1_type = TREE_TYPE (rhs1);
3953 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3955 error ("non-trivial conversion at assignment");
3956 debug_generic_expr (lhs_type);
3957 debug_generic_expr (rhs1_type);
3961 if (handled_component_p (lhs))
3962 res |= verify_types_in_gimple_reference (lhs, true);
3964 /* Special codes we cannot handle via their class. */
3969 tree op = TREE_OPERAND (rhs1, 0);
3970 if (!is_gimple_addressable (op))
3972 error ("invalid operand in unary expression");
3976 if (!types_compatible_p (TREE_TYPE (op), TREE_TYPE (TREE_TYPE (rhs1)))
3977 && !one_pointer_to_useless_type_conversion_p (TREE_TYPE (rhs1),
3980 error ("type mismatch in address expression");
3981 debug_generic_stmt (TREE_TYPE (rhs1));
3982 debug_generic_stmt (TREE_TYPE (op));
3986 return verify_types_in_gimple_reference (op, true);
3993 case ALIGN_INDIRECT_REF:
3994 case MISALIGNED_INDIRECT_REF:
3996 case ARRAY_RANGE_REF:
3997 case VIEW_CONVERT_EXPR:
4000 case TARGET_MEM_REF:
4001 if (!is_gimple_reg (lhs)
4002 && is_gimple_reg_type (TREE_TYPE (lhs)))
4004 error ("invalid rhs for gimple memory store");
4005 debug_generic_stmt (lhs);
4006 debug_generic_stmt (rhs1);
4009 return res || verify_types_in_gimple_reference (rhs1, false);
4021 /* tcc_declaration */
4026 if (!is_gimple_reg (lhs)
4027 && !is_gimple_reg (rhs1)
4028 && is_gimple_reg_type (TREE_TYPE (lhs)))
4030 error ("invalid rhs for gimple memory store");
4031 debug_generic_stmt (lhs);
4032 debug_generic_stmt (rhs1);
4041 case WITH_SIZE_EXPR:
4044 case POLYNOMIAL_CHREC:
4047 case REALIGN_LOAD_EXPR:
4057 /* Verify the contents of a GIMPLE_ASSIGN STMT. Returns true when there
4058 is a problem, otherwise false. */
4061 verify_gimple_assign (gimple stmt)
4063 switch (gimple_assign_rhs_class (stmt))
4065 case GIMPLE_SINGLE_RHS:
4066 return verify_gimple_assign_single (stmt);
4068 case GIMPLE_UNARY_RHS:
4069 return verify_gimple_assign_unary (stmt);
4071 case GIMPLE_BINARY_RHS:
4072 return verify_gimple_assign_binary (stmt);
4079 /* Verify the contents of a GIMPLE_RETURN STMT. Returns true when there
4080 is a problem, otherwise false. */
4083 verify_gimple_return (gimple stmt)
4085 tree op = gimple_return_retval (stmt);
4086 tree restype = TREE_TYPE (TREE_TYPE (cfun->decl));
4088 /* We cannot test for present return values as we do not fix up missing
4089 return values from the original source. */
4093 if (!is_gimple_val (op)
4094 && TREE_CODE (op) != RESULT_DECL)
4096 error ("invalid operand in return statement");
4097 debug_generic_stmt (op);
4101 if (!useless_type_conversion_p (restype, TREE_TYPE (op))
4102 /* ??? With C++ we can have the situation that the result
4103 decl is a reference type while the return type is an aggregate. */
4104 && !(TREE_CODE (op) == RESULT_DECL
4105 && TREE_CODE (TREE_TYPE (op)) == REFERENCE_TYPE
4106 && useless_type_conversion_p (restype, TREE_TYPE (TREE_TYPE (op)))))
4108 error ("invalid conversion in return statement");
4109 debug_generic_stmt (restype);
4110 debug_generic_stmt (TREE_TYPE (op));
4118 /* Verify the contents of a GIMPLE_GOTO STMT. Returns true when there
4119 is a problem, otherwise false. */
4122 verify_gimple_goto (gimple stmt)
4124 tree dest = gimple_goto_dest (stmt);
4126 /* ??? We have two canonical forms of direct goto destinations, a
4127 bare LABEL_DECL and an ADDR_EXPR of a LABEL_DECL. */
4128 if (TREE_CODE (dest) != LABEL_DECL
4129 && (!is_gimple_val (dest)
4130 || !POINTER_TYPE_P (TREE_TYPE (dest))))
4132 error ("goto destination is neither a label nor a pointer");
4139 /* Verify the contents of a GIMPLE_SWITCH STMT. Returns true when there
4140 is a problem, otherwise false. */
4143 verify_gimple_switch (gimple stmt)
4145 if (!is_gimple_val (gimple_switch_index (stmt)))
4147 error ("invalid operand to switch statement");
4148 debug_generic_stmt (gimple_switch_index (stmt));
4156 /* Verify the contents of a GIMPLE_PHI. Returns true if there is a problem,
4157 and false otherwise. */
4160 verify_gimple_phi (gimple stmt)
4162 tree type = TREE_TYPE (gimple_phi_result (stmt));
4165 if (TREE_CODE (gimple_phi_result (stmt)) != SSA_NAME)
4167 error ("Invalid PHI result");
4171 for (i = 0; i < gimple_phi_num_args (stmt); i++)
4173 tree arg = gimple_phi_arg_def (stmt, i);
4174 if ((is_gimple_reg (gimple_phi_result (stmt))
4175 && !is_gimple_val (arg))
4176 || (!is_gimple_reg (gimple_phi_result (stmt))
4177 && !is_gimple_addressable (arg)))
4179 error ("Invalid PHI argument");
4180 debug_generic_stmt (arg);
4183 if (!useless_type_conversion_p (type, TREE_TYPE (arg)))
4185 error ("Incompatible types in PHI argument %u", i);
4186 debug_generic_stmt (type);
4187 debug_generic_stmt (TREE_TYPE (arg));
4196 /* Verify a gimple debug statement STMT.
4197 Returns true if anything is wrong. */
4200 verify_gimple_debug (gimple stmt ATTRIBUTE_UNUSED)
4202 /* There isn't much that could be wrong in a gimple debug stmt. A
4203 gimple debug bind stmt, for example, maps a tree, that's usually
4204 a VAR_DECL or a PARM_DECL, but that could also be some scalarized
4205 component or member of an aggregate type, to another tree, that
4206 can be an arbitrary expression. These stmts expand into debug
4207 insns, and are converted to debug notes by var-tracking.c. */
4212 /* Verify the GIMPLE statement STMT. Returns true if there is an
4213 error, otherwise false. */
4216 verify_types_in_gimple_stmt (gimple stmt)
4218 switch (gimple_code (stmt))
4221 return verify_gimple_assign (stmt);
4224 return TREE_CODE (gimple_label_label (stmt)) != LABEL_DECL;
4227 return verify_gimple_call (stmt);
4230 return verify_gimple_comparison (boolean_type_node,
4231 gimple_cond_lhs (stmt),
4232 gimple_cond_rhs (stmt));
4235 return verify_gimple_goto (stmt);
4238 return verify_gimple_switch (stmt);
4241 return verify_gimple_return (stmt);
4247 return verify_gimple_phi (stmt);
4249 /* Tuples that do not have tree operands. */
4252 case GIMPLE_PREDICT:
4256 /* OpenMP directives are validated by the FE and never operated
4257 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4258 non-gimple expressions when the main index variable has had
4259 its address taken. This does not affect the loop itself
4260 because the header of an GIMPLE_OMP_FOR is merely used to determine
4261 how to setup the parallel iteration. */
4265 return verify_gimple_debug (stmt);
4272 /* Verify the GIMPLE statements inside the sequence STMTS. */
4275 verify_types_in_gimple_seq_2 (gimple_seq stmts)
4277 gimple_stmt_iterator ittr;
4280 for (ittr = gsi_start (stmts); !gsi_end_p (ittr); gsi_next (&ittr))
4282 gimple stmt = gsi_stmt (ittr);
4284 switch (gimple_code (stmt))
4287 err |= verify_types_in_gimple_seq_2 (gimple_bind_body (stmt));
4291 err |= verify_types_in_gimple_seq_2 (gimple_try_eval (stmt));
4292 err |= verify_types_in_gimple_seq_2 (gimple_try_cleanup (stmt));
4295 case GIMPLE_EH_FILTER:
4296 err |= verify_types_in_gimple_seq_2 (gimple_eh_filter_failure (stmt));
4300 err |= verify_types_in_gimple_seq_2 (gimple_catch_handler (stmt));
4305 bool err2 = verify_types_in_gimple_stmt (stmt);
4307 debug_gimple_stmt (stmt);
4317 /* Verify the GIMPLE statements inside the statement list STMTS. */
4320 verify_types_in_gimple_seq (gimple_seq stmts)
4322 if (verify_types_in_gimple_seq_2 (stmts))
4323 internal_error ("verify_gimple failed");
4327 /* Verify STMT, return true if STMT is not in GIMPLE form.
4328 TODO: Implement type checking. */
4331 verify_stmt (gimple_stmt_iterator *gsi)
4334 struct walk_stmt_info wi;
4335 bool last_in_block = gsi_one_before_end_p (*gsi);
4336 gimple stmt = gsi_stmt (*gsi);
4338 if (is_gimple_omp (stmt))
4340 /* OpenMP directives are validated by the FE and never operated
4341 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4342 non-gimple expressions when the main index variable has had
4343 its address taken. This does not affect the loop itself
4344 because the header of an GIMPLE_OMP_FOR is merely used to determine
4345 how to setup the parallel iteration. */
4349 /* FIXME. The C frontend passes unpromoted arguments in case it
4350 didn't see a function declaration before the call. */
4351 if (is_gimple_call (stmt))
4355 if (!is_gimple_call_addr (gimple_call_fn (stmt)))
4357 error ("invalid function in call statement");
4361 decl = gimple_call_fndecl (stmt);
4363 && TREE_CODE (decl) == FUNCTION_DECL
4364 && DECL_LOOPING_CONST_OR_PURE_P (decl)
4365 && (!DECL_PURE_P (decl))
4366 && (!TREE_READONLY (decl)))
4368 error ("invalid pure const state for function");
4373 if (is_gimple_debug (stmt))
4376 memset (&wi, 0, sizeof (wi));
4377 addr = walk_gimple_op (gsi_stmt (*gsi), verify_expr, &wi);
4380 debug_generic_expr (addr);
4381 inform (gimple_location (gsi_stmt (*gsi)), "in statement");
4382 debug_gimple_stmt (stmt);
4386 /* If the statement is marked as part of an EH region, then it is
4387 expected that the statement could throw. Verify that when we
4388 have optimizations that simplify statements such that we prove
4389 that they cannot throw, that we update other data structures
4391 if (lookup_stmt_eh_region (stmt) >= 0)
4393 /* During IPA passes, ipa-pure-const sets nothrow flags on calls
4394 and they are updated on statements only after fixup_cfg
4395 is executed at beggining of expansion stage. */
4396 if (!stmt_could_throw_p (stmt) && cgraph_state != CGRAPH_STATE_IPA_SSA)
4398 error ("statement marked for throw, but doesn%'t");
4401 if (!last_in_block && stmt_can_throw_internal (stmt))
4403 error ("statement marked for throw in middle of block");
4411 debug_gimple_stmt (stmt);
4416 /* Return true when the T can be shared. */
4419 tree_node_can_be_shared (tree t)
4421 if (IS_TYPE_OR_DECL_P (t)
4422 || is_gimple_min_invariant (t)
4423 || TREE_CODE (t) == SSA_NAME
4424 || t == error_mark_node
4425 || TREE_CODE (t) == IDENTIFIER_NODE)
4428 if (TREE_CODE (t) == CASE_LABEL_EXPR)
4431 while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4432 && is_gimple_min_invariant (TREE_OPERAND (t, 1)))
4433 || TREE_CODE (t) == COMPONENT_REF
4434 || TREE_CODE (t) == REALPART_EXPR
4435 || TREE_CODE (t) == IMAGPART_EXPR)
4436 t = TREE_OPERAND (t, 0);
4445 /* Called via walk_gimple_stmt. Verify tree sharing. */
4448 verify_node_sharing (tree *tp, int *walk_subtrees, void *data)
4450 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
4451 struct pointer_set_t *visited = (struct pointer_set_t *) wi->info;
4453 if (tree_node_can_be_shared (*tp))
4455 *walk_subtrees = false;
4459 if (pointer_set_insert (visited, *tp))
4466 static bool eh_error_found;
4468 verify_eh_throw_stmt_node (void **slot, void *data)
4470 struct throw_stmt_node *node = (struct throw_stmt_node *)*slot;
4471 struct pointer_set_t *visited = (struct pointer_set_t *) data;
4473 if (!pointer_set_contains (visited, node->stmt))
4475 error ("Dead STMT in EH table");
4476 debug_gimple_stmt (node->stmt);
4477 eh_error_found = true;
4483 /* Verify the GIMPLE statements in every basic block. */
4489 gimple_stmt_iterator gsi;
4491 struct pointer_set_t *visited, *visited_stmts;
4493 struct walk_stmt_info wi;
4495 timevar_push (TV_TREE_STMT_VERIFY);
4496 visited = pointer_set_create ();
4497 visited_stmts = pointer_set_create ();
4499 memset (&wi, 0, sizeof (wi));
4500 wi.info = (void *) visited;
4507 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4509 phi = gsi_stmt (gsi);
4510 pointer_set_insert (visited_stmts, phi);
4511 if (gimple_bb (phi) != bb)
4513 error ("gimple_bb (phi) is set to a wrong basic block");
4517 for (i = 0; i < gimple_phi_num_args (phi); i++)
4519 tree t = gimple_phi_arg_def (phi, i);
4524 error ("missing PHI def");
4525 debug_gimple_stmt (phi);
4529 /* Addressable variables do have SSA_NAMEs but they
4530 are not considered gimple values. */
4531 else if (TREE_CODE (t) != SSA_NAME
4532 && TREE_CODE (t) != FUNCTION_DECL
4533 && !is_gimple_min_invariant (t))
4535 error ("PHI argument is not a GIMPLE value");
4536 debug_gimple_stmt (phi);
4537 debug_generic_expr (t);
4541 addr = walk_tree (&t, verify_node_sharing, visited, NULL);
4544 error ("incorrect sharing of tree nodes");
4545 debug_gimple_stmt (phi);
4546 debug_generic_expr (addr);
4551 #ifdef ENABLE_TYPES_CHECKING
4552 if (verify_gimple_phi (phi))
4554 debug_gimple_stmt (phi);
4560 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); )
4562 gimple stmt = gsi_stmt (gsi);
4564 if (gimple_code (stmt) == GIMPLE_WITH_CLEANUP_EXPR
4565 || gimple_code (stmt) == GIMPLE_BIND)
4567 error ("invalid GIMPLE statement");
4568 debug_gimple_stmt (stmt);
4572 pointer_set_insert (visited_stmts, stmt);
4574 if (gimple_bb (stmt) != bb)
4576 error ("gimple_bb (stmt) is set to a wrong basic block");
4577 debug_gimple_stmt (stmt);
4581 if (gimple_code (stmt) == GIMPLE_LABEL)
4583 tree decl = gimple_label_label (stmt);
4584 int uid = LABEL_DECL_UID (decl);
4587 || VEC_index (basic_block, label_to_block_map, uid) != bb)
4589 error ("incorrect entry in label_to_block_map.\n");
4594 err |= verify_stmt (&gsi);
4596 #ifdef ENABLE_TYPES_CHECKING
4597 if (verify_types_in_gimple_stmt (gsi_stmt (gsi)))
4599 debug_gimple_stmt (stmt);
4603 addr = walk_gimple_op (gsi_stmt (gsi), verify_node_sharing, &wi);
4606 error ("incorrect sharing of tree nodes");
4607 debug_gimple_stmt (stmt);
4608 debug_generic_expr (addr);
4615 eh_error_found = false;
4616 if (get_eh_throw_stmt_table (cfun))
4617 htab_traverse (get_eh_throw_stmt_table (cfun),
4618 verify_eh_throw_stmt_node,
4621 if (err | eh_error_found)
4622 internal_error ("verify_stmts failed");
4624 pointer_set_destroy (visited);
4625 pointer_set_destroy (visited_stmts);
4626 verify_histograms ();
4627 timevar_pop (TV_TREE_STMT_VERIFY);
4631 /* Verifies that the flow information is OK. */
4634 gimple_verify_flow_info (void)
4638 gimple_stmt_iterator gsi;
4643 if (ENTRY_BLOCK_PTR->il.gimple)
4645 error ("ENTRY_BLOCK has IL associated with it");
4649 if (EXIT_BLOCK_PTR->il.gimple)
4651 error ("EXIT_BLOCK has IL associated with it");
4655 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4656 if (e->flags & EDGE_FALLTHRU)
4658 error ("fallthru to exit from bb %d", e->src->index);
4664 bool found_ctrl_stmt = false;
4668 /* Skip labels on the start of basic block. */
4669 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4672 gimple prev_stmt = stmt;
4674 stmt = gsi_stmt (gsi);
4676 if (gimple_code (stmt) != GIMPLE_LABEL)
4679 label = gimple_label_label (stmt);
4680 if (prev_stmt && DECL_NONLOCAL (label))
4682 error ("nonlocal label ");
4683 print_generic_expr (stderr, label, 0);
4684 fprintf (stderr, " is not first in a sequence of labels in bb %d",
4689 if (label_to_block (label) != bb)
4692 print_generic_expr (stderr, label, 0);
4693 fprintf (stderr, " to block does not match in bb %d",
4698 if (decl_function_context (label) != current_function_decl)
4701 print_generic_expr (stderr, label, 0);
4702 fprintf (stderr, " has incorrect context in bb %d",
4708 /* Verify that body of basic block BB is free of control flow. */
4709 for (; !gsi_end_p (gsi); gsi_next (&gsi))
4711 gimple stmt = gsi_stmt (gsi);
4713 if (found_ctrl_stmt)
4715 error ("control flow in the middle of basic block %d",
4720 if (stmt_ends_bb_p (stmt))
4721 found_ctrl_stmt = true;
4723 if (gimple_code (stmt) == GIMPLE_LABEL)
4726 print_generic_expr (stderr, gimple_label_label (stmt), 0);
4727 fprintf (stderr, " in the middle of basic block %d", bb->index);
4732 gsi = gsi_last_bb (bb);
4733 if (gsi_end_p (gsi))
4736 stmt = gsi_stmt (gsi);
4738 err |= verify_eh_edges (stmt);
4740 if (is_ctrl_stmt (stmt))
4742 FOR_EACH_EDGE (e, ei, bb->succs)
4743 if (e->flags & EDGE_FALLTHRU)
4745 error ("fallthru edge after a control statement in bb %d",
4751 if (gimple_code (stmt) != GIMPLE_COND)
4753 /* Verify that there are no edges with EDGE_TRUE/FALSE_FLAG set
4754 after anything else but if statement. */
4755 FOR_EACH_EDGE (e, ei, bb->succs)
4756 if (e->flags & (EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))
4758 error ("true/false edge after a non-GIMPLE_COND in bb %d",
4764 switch (gimple_code (stmt))
4771 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
4775 || !(true_edge->flags & EDGE_TRUE_VALUE)
4776 || !(false_edge->flags & EDGE_FALSE_VALUE)
4777 || (true_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4778 || (false_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4779 || EDGE_COUNT (bb->succs) >= 3)
4781 error ("wrong outgoing edge flags at end of bb %d",
4789 if (simple_goto_p (stmt))
4791 error ("explicit goto at end of bb %d", bb->index);
4796 /* FIXME. We should double check that the labels in the
4797 destination blocks have their address taken. */
4798 FOR_EACH_EDGE (e, ei, bb->succs)
4799 if ((e->flags & (EDGE_FALLTHRU | EDGE_TRUE_VALUE
4800 | EDGE_FALSE_VALUE))
4801 || !(e->flags & EDGE_ABNORMAL))
4803 error ("wrong outgoing edge flags at end of bb %d",
4811 if (!single_succ_p (bb)
4812 || (single_succ_edge (bb)->flags
4813 & (EDGE_FALLTHRU | EDGE_ABNORMAL
4814 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4816 error ("wrong outgoing edge flags at end of bb %d", bb->index);
4819 if (single_succ (bb) != EXIT_BLOCK_PTR)
4821 error ("return edge does not point to exit in bb %d",
4833 n = gimple_switch_num_labels (stmt);
4835 /* Mark all the destination basic blocks. */
4836 for (i = 0; i < n; ++i)
4838 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4839 basic_block label_bb = label_to_block (lab);
4840 gcc_assert (!label_bb->aux || label_bb->aux == (void *)1);
4841 label_bb->aux = (void *)1;
4844 /* Verify that the case labels are sorted. */
4845 prev = gimple_switch_label (stmt, 0);
4846 for (i = 1; i < n; ++i)
4848 tree c = gimple_switch_label (stmt, i);
4851 error ("found default case not at the start of "
4857 && !tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c)))
4859 error ("case labels not sorted: ");
4860 print_generic_expr (stderr, prev, 0);
4861 fprintf (stderr," is greater than ");
4862 print_generic_expr (stderr, c, 0);
4863 fprintf (stderr," but comes before it.\n");
4868 /* VRP will remove the default case if it can prove it will
4869 never be executed. So do not verify there always exists
4870 a default case here. */
4872 FOR_EACH_EDGE (e, ei, bb->succs)
4876 error ("extra outgoing edge %d->%d",
4877 bb->index, e->dest->index);
4881 e->dest->aux = (void *)2;
4882 if ((e->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL
4883 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4885 error ("wrong outgoing edge flags at end of bb %d",
4891 /* Check that we have all of them. */
4892 for (i = 0; i < n; ++i)
4894 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4895 basic_block label_bb = label_to_block (lab);
4897 if (label_bb->aux != (void *)2)
4899 error ("missing edge %i->%i", bb->index, label_bb->index);
4904 FOR_EACH_EDGE (e, ei, bb->succs)
4905 e->dest->aux = (void *)0;
4912 if (dom_info_state (CDI_DOMINATORS) >= DOM_NO_FAST_QUERY)
4913 verify_dominators (CDI_DOMINATORS);
4919 /* Updates phi nodes after creating a forwarder block joined
4920 by edge FALLTHRU. */
4923 gimple_make_forwarder_block (edge fallthru)
4927 basic_block dummy, bb;
4929 gimple_stmt_iterator gsi;
4931 dummy = fallthru->src;
4932 bb = fallthru->dest;
4934 if (single_pred_p (bb))
4937 /* If we redirected a branch we must create new PHI nodes at the
4939 for (gsi = gsi_start_phis (dummy); !gsi_end_p (gsi); gsi_next (&gsi))
4941 gimple phi, new_phi;
4943 phi = gsi_stmt (gsi);
4944 var = gimple_phi_result (phi);
4945 new_phi = create_phi_node (var, bb);
4946 SSA_NAME_DEF_STMT (var) = new_phi;
4947 gimple_phi_set_result (phi, make_ssa_name (SSA_NAME_VAR (var), phi));
4948 add_phi_arg (new_phi, gimple_phi_result (phi), fallthru,
4952 /* Add the arguments we have stored on edges. */
4953 FOR_EACH_EDGE (e, ei, bb->preds)
4958 flush_pending_stmts (e);
4963 /* Return a non-special label in the head of basic block BLOCK.
4964 Create one if it doesn't exist. */
4967 gimple_block_label (basic_block bb)
4969 gimple_stmt_iterator i, s = gsi_start_bb (bb);
4974 for (i = s; !gsi_end_p (i); first = false, gsi_next (&i))
4976 stmt = gsi_stmt (i);
4977 if (gimple_code (stmt) != GIMPLE_LABEL)
4979 label = gimple_label_label (stmt);
4980 if (!DECL_NONLOCAL (label))
4983 gsi_move_before (&i, &s);
4988 label = create_artificial_label (UNKNOWN_LOCATION);
4989 stmt = gimple_build_label (label);
4990 gsi_insert_before (&s, stmt, GSI_NEW_STMT);
4995 /* Attempt to perform edge redirection by replacing a possibly complex
4996 jump instruction by a goto or by removing the jump completely.
4997 This can apply only if all edges now point to the same block. The
4998 parameters and return values are equivalent to
4999 redirect_edge_and_branch. */
5002 gimple_try_redirect_by_replacing_jump (edge e, basic_block target)
5004 basic_block src = e->src;
5005 gimple_stmt_iterator i;
5008 /* We can replace or remove a complex jump only when we have exactly
5010 if (EDGE_COUNT (src->succs) != 2
5011 /* Verify that all targets will be TARGET. Specifically, the
5012 edge that is not E must also go to TARGET. */
5013 || EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)
5016 i = gsi_last_bb (src);
5020 stmt = gsi_stmt (i);
5022 if (gimple_code (stmt) == GIMPLE_COND || gimple_code (stmt) == GIMPLE_SWITCH)
5024 gsi_remove (&i, true);
5025 e = ssa_redirect_edge (e, target);
5026 e->flags = EDGE_FALLTHRU;
5034 /* Redirect E to DEST. Return NULL on failure. Otherwise, return the
5035 edge representing the redirected branch. */
5038 gimple_redirect_edge_and_branch (edge e, basic_block dest)
5040 basic_block bb = e->src;
5041 gimple_stmt_iterator gsi;
5045 if (e->flags & EDGE_ABNORMAL)
5048 if (e->dest == dest)
5051 if (e->flags & EDGE_EH)
5052 return redirect_eh_edge (e, dest);
5054 if (e->src != ENTRY_BLOCK_PTR)
5056 ret = gimple_try_redirect_by_replacing_jump (e, dest);
5061 gsi = gsi_last_bb (bb);
5062 stmt = gsi_end_p (gsi) ? NULL : gsi_stmt (gsi);
5064 switch (stmt ? gimple_code (stmt) : GIMPLE_ERROR_MARK)
5067 /* For COND_EXPR, we only need to redirect the edge. */
5071 /* No non-abnormal edges should lead from a non-simple goto, and
5072 simple ones should be represented implicitly. */
5077 tree label = gimple_block_label (dest);
5078 tree cases = get_cases_for_edge (e, stmt);
5080 /* If we have a list of cases associated with E, then use it
5081 as it's a lot faster than walking the entire case vector. */
5084 edge e2 = find_edge (e->src, dest);
5091 CASE_LABEL (cases) = label;
5092 cases = TREE_CHAIN (cases);
5095 /* If there was already an edge in the CFG, then we need
5096 to move all the cases associated with E to E2. */
5099 tree cases2 = get_cases_for_edge (e2, stmt);
5101 TREE_CHAIN (last) = TREE_CHAIN (cases2);
5102 TREE_CHAIN (cases2) = first;
5107 size_t i, n = gimple_switch_num_labels (stmt);
5109 for (i = 0; i < n; i++)
5111 tree elt = gimple_switch_label (stmt, i);
5112 if (label_to_block (CASE_LABEL (elt)) == e->dest)
5113 CASE_LABEL (elt) = label;
5121 gsi_remove (&gsi, true);
5122 e->flags |= EDGE_FALLTHRU;
5125 case GIMPLE_OMP_RETURN:
5126 case GIMPLE_OMP_CONTINUE:
5127 case GIMPLE_OMP_SECTIONS_SWITCH:
5128 case GIMPLE_OMP_FOR:
5129 /* The edges from OMP constructs can be simply redirected. */
5133 /* Otherwise it must be a fallthru edge, and we don't need to
5134 do anything besides redirecting it. */
5135 gcc_assert (e->flags & EDGE_FALLTHRU);
5139 /* Update/insert PHI nodes as necessary. */
5141 /* Now update the edges in the CFG. */
5142 e = ssa_redirect_edge (e, dest);
5147 /* Returns true if it is possible to remove edge E by redirecting
5148 it to the destination of the other edge from E->src. */
5151 gimple_can_remove_branch_p (const_edge e)
5153 if (e->flags & (EDGE_ABNORMAL | EDGE_EH))
5159 /* Simple wrapper, as we can always redirect fallthru edges. */
5162 gimple_redirect_edge_and_branch_force (edge e, basic_block dest)
5164 e = gimple_redirect_edge_and_branch (e, dest);
5171 /* Splits basic block BB after statement STMT (but at least after the
5172 labels). If STMT is NULL, BB is split just after the labels. */
5175 gimple_split_block (basic_block bb, void *stmt)
5177 gimple_stmt_iterator gsi;
5178 gimple_stmt_iterator gsi_tgt;
5185 new_bb = create_empty_bb (bb);
5187 /* Redirect the outgoing edges. */
5188 new_bb->succs = bb->succs;
5190 FOR_EACH_EDGE (e, ei, new_bb->succs)
5193 if (stmt && gimple_code ((gimple) stmt) == GIMPLE_LABEL)
5196 /* Move everything from GSI to the new basic block. */
5197 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5199 act = gsi_stmt (gsi);
5200 if (gimple_code (act) == GIMPLE_LABEL)
5213 if (gsi_end_p (gsi))
5216 /* Split the statement list - avoid re-creating new containers as this
5217 brings ugly quadratic memory consumption in the inliner.
5218 (We are still quadratic since we need to update stmt BB pointers,
5220 list = gsi_split_seq_before (&gsi);
5221 set_bb_seq (new_bb, list);
5222 for (gsi_tgt = gsi_start (list);
5223 !gsi_end_p (gsi_tgt); gsi_next (&gsi_tgt))
5224 gimple_set_bb (gsi_stmt (gsi_tgt), new_bb);
5230 /* Moves basic block BB after block AFTER. */
5233 gimple_move_block_after (basic_block bb, basic_block after)
5235 if (bb->prev_bb == after)
5239 link_block (bb, after);
5245 /* Return true if basic_block can be duplicated. */
5248 gimple_can_duplicate_bb_p (const_basic_block bb ATTRIBUTE_UNUSED)
5253 /* Create a duplicate of the basic block BB. NOTE: This does not
5254 preserve SSA form. */
5257 gimple_duplicate_bb (basic_block bb)
5260 gimple_stmt_iterator gsi, gsi_tgt;
5261 gimple_seq phis = phi_nodes (bb);
5262 gimple phi, stmt, copy;
5264 new_bb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb);
5266 /* Copy the PHI nodes. We ignore PHI node arguments here because
5267 the incoming edges have not been setup yet. */
5268 for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
5270 phi = gsi_stmt (gsi);
5271 copy = create_phi_node (gimple_phi_result (phi), new_bb);
5272 create_new_def_for (gimple_phi_result (copy), copy,
5273 gimple_phi_result_ptr (copy));
5276 gsi_tgt = gsi_start_bb (new_bb);
5277 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5279 def_operand_p def_p;
5280 ssa_op_iter op_iter;
5283 stmt = gsi_stmt (gsi);
5284 if (gimple_code (stmt) == GIMPLE_LABEL)
5287 /* Create a new copy of STMT and duplicate STMT's virtual
5289 copy = gimple_copy (stmt);
5290 gsi_insert_after (&gsi_tgt, copy, GSI_NEW_STMT);
5291 region = lookup_stmt_eh_region (stmt);
5293 add_stmt_to_eh_region (copy, region);
5294 gimple_duplicate_stmt_histograms (cfun, copy, cfun, stmt);
5296 /* Create new names for all the definitions created by COPY and
5297 add replacement mappings for each new name. */
5298 FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS)
5299 create_new_def_for (DEF_FROM_PTR (def_p), copy, def_p);
5305 /* Adds phi node arguments for edge E_COPY after basic block duplication. */
5308 add_phi_args_after_copy_edge (edge e_copy)
5310 basic_block bb, bb_copy = e_copy->src, dest;
5313 gimple phi, phi_copy;
5315 gimple_stmt_iterator psi, psi_copy;
5317 if (gimple_seq_empty_p (phi_nodes (e_copy->dest)))
5320 bb = bb_copy->flags & BB_DUPLICATED ? get_bb_original (bb_copy) : bb_copy;
5322 if (e_copy->dest->flags & BB_DUPLICATED)
5323 dest = get_bb_original (e_copy->dest);
5325 dest = e_copy->dest;
5327 e = find_edge (bb, dest);
5330 /* During loop unrolling the target of the latch edge is copied.
5331 In this case we are not looking for edge to dest, but to
5332 duplicated block whose original was dest. */
5333 FOR_EACH_EDGE (e, ei, bb->succs)
5335 if ((e->dest->flags & BB_DUPLICATED)
5336 && get_bb_original (e->dest) == dest)
5340 gcc_assert (e != NULL);
5343 for (psi = gsi_start_phis (e->dest),
5344 psi_copy = gsi_start_phis (e_copy->dest);
5346 gsi_next (&psi), gsi_next (&psi_copy))
5348 phi = gsi_stmt (psi);
5349 phi_copy = gsi_stmt (psi_copy);
5350 def = PHI_ARG_DEF_FROM_EDGE (phi, e);
5351 add_phi_arg (phi_copy, def, e_copy,
5352 gimple_phi_arg_location_from_edge (phi, e));
5357 /* Basic block BB_COPY was created by code duplication. Add phi node
5358 arguments for edges going out of BB_COPY. The blocks that were
5359 duplicated have BB_DUPLICATED set. */
5362 add_phi_args_after_copy_bb (basic_block bb_copy)
5367 FOR_EACH_EDGE (e_copy, ei, bb_copy->succs)
5369 add_phi_args_after_copy_edge (e_copy);
5373 /* Blocks in REGION_COPY array of length N_REGION were created by
5374 duplication of basic blocks. Add phi node arguments for edges
5375 going from these blocks. If E_COPY is not NULL, also add
5376 phi node arguments for its destination.*/
5379 add_phi_args_after_copy (basic_block *region_copy, unsigned n_region,
5384 for (i = 0; i < n_region; i++)
5385 region_copy[i]->flags |= BB_DUPLICATED;
5387 for (i = 0; i < n_region; i++)
5388 add_phi_args_after_copy_bb (region_copy[i]);
5390 add_phi_args_after_copy_edge (e_copy);
5392 for (i = 0; i < n_region; i++)
5393 region_copy[i]->flags &= ~BB_DUPLICATED;
5396 /* Duplicates a REGION (set of N_REGION basic blocks) with just a single
5397 important exit edge EXIT. By important we mean that no SSA name defined
5398 inside region is live over the other exit edges of the region. All entry
5399 edges to the region must go to ENTRY->dest. The edge ENTRY is redirected
5400 to the duplicate of the region. SSA form, dominance and loop information
5401 is updated. The new basic blocks are stored to REGION_COPY in the same
5402 order as they had in REGION, provided that REGION_COPY is not NULL.
5403 The function returns false if it is unable to copy the region,
5407 gimple_duplicate_sese_region (edge entry, edge exit,
5408 basic_block *region, unsigned n_region,
5409 basic_block *region_copy)
5412 bool free_region_copy = false, copying_header = false;
5413 struct loop *loop = entry->dest->loop_father;
5415 VEC (basic_block, heap) *doms;
5417 int total_freq = 0, entry_freq = 0;
5418 gcov_type total_count = 0, entry_count = 0;
5420 if (!can_copy_bbs_p (region, n_region))
5423 /* Some sanity checking. Note that we do not check for all possible
5424 missuses of the functions. I.e. if you ask to copy something weird,
5425 it will work, but the state of structures probably will not be
5427 for (i = 0; i < n_region; i++)
5429 /* We do not handle subloops, i.e. all the blocks must belong to the
5431 if (region[i]->loop_father != loop)
5434 if (region[i] != entry->dest
5435 && region[i] == loop->header)
5439 set_loop_copy (loop, loop);
5441 /* In case the function is used for loop header copying (which is the primary
5442 use), ensure that EXIT and its copy will be new latch and entry edges. */
5443 if (loop->header == entry->dest)
5445 copying_header = true;
5446 set_loop_copy (loop, loop_outer (loop));
5448 if (!dominated_by_p (CDI_DOMINATORS, loop->latch, exit->src))
5451 for (i = 0; i < n_region; i++)
5452 if (region[i] != exit->src
5453 && dominated_by_p (CDI_DOMINATORS, region[i], exit->src))
5459 region_copy = XNEWVEC (basic_block, n_region);
5460 free_region_copy = true;
5463 gcc_assert (!need_ssa_update_p (cfun));
5465 /* Record blocks outside the region that are dominated by something
5468 initialize_original_copy_tables ();
5470 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5472 if (entry->dest->count)
5474 total_count = entry->dest->count;
5475 entry_count = entry->count;
5476 /* Fix up corner cases, to avoid division by zero or creation of negative
5478 if (entry_count > total_count)
5479 entry_count = total_count;
5483 total_freq = entry->dest->frequency;
5484 entry_freq = EDGE_FREQUENCY (entry);
5485 /* Fix up corner cases, to avoid division by zero or creation of negative
5487 if (total_freq == 0)
5489 else if (entry_freq > total_freq)
5490 entry_freq = total_freq;
5493 copy_bbs (region, n_region, region_copy, &exit, 1, &exit_copy, loop,
5494 split_edge_bb_loc (entry));
5497 scale_bbs_frequencies_gcov_type (region, n_region,
5498 total_count - entry_count,
5500 scale_bbs_frequencies_gcov_type (region_copy, n_region, entry_count,
5505 scale_bbs_frequencies_int (region, n_region, total_freq - entry_freq,
5507 scale_bbs_frequencies_int (region_copy, n_region, entry_freq, total_freq);
5512 loop->header = exit->dest;
5513 loop->latch = exit->src;
5516 /* Redirect the entry and add the phi node arguments. */
5517 redirected = redirect_edge_and_branch (entry, get_bb_copy (entry->dest));
5518 gcc_assert (redirected != NULL);
5519 flush_pending_stmts (entry);
5521 /* Concerning updating of dominators: We must recount dominators
5522 for entry block and its copy. Anything that is outside of the
5523 region, but was dominated by something inside needs recounting as
5525 set_immediate_dominator (CDI_DOMINATORS, entry->dest, entry->src);
5526 VEC_safe_push (basic_block, heap, doms, get_bb_original (entry->dest));
5527 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5528 VEC_free (basic_block, heap, doms);
5530 /* Add the other PHI node arguments. */
5531 add_phi_args_after_copy (region_copy, n_region, NULL);
5533 /* Update the SSA web. */
5534 update_ssa (TODO_update_ssa);
5536 if (free_region_copy)
5539 free_original_copy_tables ();
5543 /* Duplicates REGION consisting of N_REGION blocks. The new blocks
5544 are stored to REGION_COPY in the same order in that they appear
5545 in REGION, if REGION_COPY is not NULL. ENTRY is the entry to
5546 the region, EXIT an exit from it. The condition guarding EXIT
5547 is moved to ENTRY. Returns true if duplication succeeds, false
5573 gimple_duplicate_sese_tail (edge entry ATTRIBUTE_UNUSED, edge exit ATTRIBUTE_UNUSED,
5574 basic_block *region ATTRIBUTE_UNUSED, unsigned n_region ATTRIBUTE_UNUSED,
5575 basic_block *region_copy ATTRIBUTE_UNUSED)
5578 bool free_region_copy = false;
5579 struct loop *loop = exit->dest->loop_father;
5580 struct loop *orig_loop = entry->dest->loop_father;
5581 basic_block switch_bb, entry_bb, nentry_bb;
5582 VEC (basic_block, heap) *doms;
5583 int total_freq = 0, exit_freq = 0;
5584 gcov_type total_count = 0, exit_count = 0;
5585 edge exits[2], nexits[2], e;
5586 gimple_stmt_iterator gsi;
5590 gcc_assert (EDGE_COUNT (exit->src->succs) == 2);
5592 exits[1] = EDGE_SUCC (exit->src, EDGE_SUCC (exit->src, 0) == exit);
5594 if (!can_copy_bbs_p (region, n_region))
5597 /* Some sanity checking. Note that we do not check for all possible
5598 missuses of the functions. I.e. if you ask to copy something weird
5599 (e.g., in the example, if there is a jump from inside to the middle
5600 of some_code, or come_code defines some of the values used in cond)
5601 it will work, but the resulting code will not be correct. */
5602 for (i = 0; i < n_region; i++)
5604 /* We do not handle subloops, i.e. all the blocks must belong to the
5606 if (region[i]->loop_father != orig_loop)
5609 if (region[i] == orig_loop->latch)
5613 initialize_original_copy_tables ();
5614 set_loop_copy (orig_loop, loop);
5618 region_copy = XNEWVEC (basic_block, n_region);
5619 free_region_copy = true;
5622 gcc_assert (!need_ssa_update_p (cfun));
5624 /* Record blocks outside the region that are dominated by something
5626 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5628 if (exit->src->count)
5630 total_count = exit->src->count;
5631 exit_count = exit->count;
5632 /* Fix up corner cases, to avoid division by zero or creation of negative
5634 if (exit_count > total_count)
5635 exit_count = total_count;
5639 total_freq = exit->src->frequency;
5640 exit_freq = EDGE_FREQUENCY (exit);
5641 /* Fix up corner cases, to avoid division by zero or creation of negative
5643 if (total_freq == 0)
5645 if (exit_freq > total_freq)
5646 exit_freq = total_freq;
5649 copy_bbs (region, n_region, region_copy, exits, 2, nexits, orig_loop,
5650 split_edge_bb_loc (exit));
5653 scale_bbs_frequencies_gcov_type (region, n_region,
5654 total_count - exit_count,
5656 scale_bbs_frequencies_gcov_type (region_copy, n_region, exit_count,
5661 scale_bbs_frequencies_int (region, n_region, total_freq - exit_freq,
5663 scale_bbs_frequencies_int (region_copy, n_region, exit_freq, total_freq);
5666 /* Create the switch block, and put the exit condition to it. */
5667 entry_bb = entry->dest;
5668 nentry_bb = get_bb_copy (entry_bb);
5669 if (!last_stmt (entry->src)
5670 || !stmt_ends_bb_p (last_stmt (entry->src)))
5671 switch_bb = entry->src;
5673 switch_bb = split_edge (entry);
5674 set_immediate_dominator (CDI_DOMINATORS, nentry_bb, switch_bb);
5676 gsi = gsi_last_bb (switch_bb);
5677 cond_stmt = last_stmt (exit->src);
5678 gcc_assert (gimple_code (cond_stmt) == GIMPLE_COND);
5679 cond_stmt = gimple_copy (cond_stmt);
5680 gimple_cond_set_lhs (cond_stmt, unshare_expr (gimple_cond_lhs (cond_stmt)));
5681 gimple_cond_set_rhs (cond_stmt, unshare_expr (gimple_cond_rhs (cond_stmt)));
5682 gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT);
5684 sorig = single_succ_edge (switch_bb);
5685 sorig->flags = exits[1]->flags;
5686 snew = make_edge (switch_bb, nentry_bb, exits[0]->flags);
5688 /* Register the new edge from SWITCH_BB in loop exit lists. */
5689 rescan_loop_exit (snew, true, false);
5691 /* Add the PHI node arguments. */
5692 add_phi_args_after_copy (region_copy, n_region, snew);
5694 /* Get rid of now superfluous conditions and associated edges (and phi node
5696 e = redirect_edge_and_branch (exits[0], exits[1]->dest);
5697 PENDING_STMT (e) = NULL;
5698 e = redirect_edge_and_branch (nexits[1], nexits[0]->dest);
5699 PENDING_STMT (e) = NULL;
5701 /* Anything that is outside of the region, but was dominated by something
5702 inside needs to update dominance info. */
5703 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5704 VEC_free (basic_block, heap, doms);
5706 /* Update the SSA web. */
5707 update_ssa (TODO_update_ssa);
5709 if (free_region_copy)
5712 free_original_copy_tables ();
5716 /* Add all the blocks dominated by ENTRY to the array BBS_P. Stop
5717 adding blocks when the dominator traversal reaches EXIT. This
5718 function silently assumes that ENTRY strictly dominates EXIT. */
5721 gather_blocks_in_sese_region (basic_block entry, basic_block exit,
5722 VEC(basic_block,heap) **bbs_p)
5726 for (son = first_dom_son (CDI_DOMINATORS, entry);
5728 son = next_dom_son (CDI_DOMINATORS, son))
5730 VEC_safe_push (basic_block, heap, *bbs_p, son);
5732 gather_blocks_in_sese_region (son, exit, bbs_p);
5736 /* Replaces *TP with a duplicate (belonging to function TO_CONTEXT).
5737 The duplicates are recorded in VARS_MAP. */
5740 replace_by_duplicate_decl (tree *tp, struct pointer_map_t *vars_map,
5743 tree t = *tp, new_t;
5744 struct function *f = DECL_STRUCT_FUNCTION (to_context);
5747 if (DECL_CONTEXT (t) == to_context)
5750 loc = pointer_map_contains (vars_map, t);
5754 loc = pointer_map_insert (vars_map, t);
5758 new_t = copy_var_decl (t, DECL_NAME (t), TREE_TYPE (t));
5759 f->local_decls = tree_cons (NULL_TREE, new_t, f->local_decls);
5763 gcc_assert (TREE_CODE (t) == CONST_DECL);
5764 new_t = copy_node (t);
5766 DECL_CONTEXT (new_t) = to_context;
5771 new_t = (tree) *loc;
5777 /* Creates an ssa name in TO_CONTEXT equivalent to NAME.
5778 VARS_MAP maps old ssa names and var_decls to the new ones. */
5781 replace_ssa_name (tree name, struct pointer_map_t *vars_map,
5785 tree new_name, decl = SSA_NAME_VAR (name);
5787 gcc_assert (is_gimple_reg (name));
5789 loc = pointer_map_contains (vars_map, name);
5793 replace_by_duplicate_decl (&decl, vars_map, to_context);
5795 push_cfun (DECL_STRUCT_FUNCTION (to_context));
5796 if (gimple_in_ssa_p (cfun))
5797 add_referenced_var (decl);
5799 new_name = make_ssa_name (decl, SSA_NAME_DEF_STMT (name));
5800 if (SSA_NAME_IS_DEFAULT_DEF (name))
5801 set_default_def (decl, new_name);
5804 loc = pointer_map_insert (vars_map, name);
5808 new_name = (tree) *loc;
5819 struct pointer_map_t *vars_map;
5820 htab_t new_label_map;
5824 /* Helper for move_block_to_fn. Set TREE_BLOCK in every expression
5825 contained in *TP if it has been ORIG_BLOCK previously and change the
5826 DECL_CONTEXT of every local variable referenced in *TP. */
5829 move_stmt_op (tree *tp, int *walk_subtrees, void *data)
5831 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
5832 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5836 /* We should never have TREE_BLOCK set on non-statements. */
5837 gcc_assert (!TREE_BLOCK (t));
5839 else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
5841 if (TREE_CODE (t) == SSA_NAME)
5842 *tp = replace_ssa_name (t, p->vars_map, p->to_context);
5843 else if (TREE_CODE (t) == LABEL_DECL)
5845 if (p->new_label_map)
5847 struct tree_map in, *out;
5849 out = (struct tree_map *)
5850 htab_find_with_hash (p->new_label_map, &in, DECL_UID (t));
5855 DECL_CONTEXT (t) = p->to_context;
5857 else if (p->remap_decls_p)
5859 /* Replace T with its duplicate. T should no longer appear in the
5860 parent function, so this looks wasteful; however, it may appear
5861 in referenced_vars, and more importantly, as virtual operands of
5862 statements, and in alias lists of other variables. It would be
5863 quite difficult to expunge it from all those places. ??? It might
5864 suffice to do this for addressable variables. */
5865 if ((TREE_CODE (t) == VAR_DECL
5866 && !is_global_var (t))
5867 || TREE_CODE (t) == CONST_DECL)
5868 replace_by_duplicate_decl (tp, p->vars_map, p->to_context);
5871 && gimple_in_ssa_p (cfun))
5873 push_cfun (DECL_STRUCT_FUNCTION (p->to_context));
5874 add_referenced_var (*tp);
5880 else if (TYPE_P (t))
5886 /* Like move_stmt_op, but for gimple statements.
5888 Helper for move_block_to_fn. Set GIMPLE_BLOCK in every expression
5889 contained in the current statement in *GSI_P and change the
5890 DECL_CONTEXT of every local variable referenced in the current
5894 move_stmt_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
5895 struct walk_stmt_info *wi)
5897 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5898 gimple stmt = gsi_stmt (*gsi_p);
5899 tree block = gimple_block (stmt);
5901 if (p->orig_block == NULL_TREE
5902 || block == p->orig_block
5903 || block == NULL_TREE)
5904 gimple_set_block (stmt, p->new_block);
5905 #ifdef ENABLE_CHECKING
5906 else if (block != p->new_block)
5908 while (block && block != p->orig_block)
5909 block = BLOCK_SUPERCONTEXT (block);
5914 if (is_gimple_omp (stmt)
5915 && gimple_code (stmt) != GIMPLE_OMP_RETURN
5916 && gimple_code (stmt) != GIMPLE_OMP_CONTINUE)
5918 /* Do not remap variables inside OMP directives. Variables
5919 referenced in clauses and directive header belong to the
5920 parent function and should not be moved into the child
5922 bool save_remap_decls_p = p->remap_decls_p;
5923 p->remap_decls_p = false;
5924 *handled_ops_p = true;
5926 walk_gimple_seq (gimple_omp_body (stmt), move_stmt_r, move_stmt_op, wi);
5928 p->remap_decls_p = save_remap_decls_p;
5934 /* Marks virtual operands of all statements in basic blocks BBS for
5938 mark_virtual_ops_in_bb (basic_block bb)
5940 gimple_stmt_iterator gsi;
5942 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5943 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5945 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5946 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5949 /* Move basic block BB from function CFUN to function DEST_FN. The
5950 block is moved out of the original linked list and placed after
5951 block AFTER in the new list. Also, the block is removed from the
5952 original array of blocks and placed in DEST_FN's array of blocks.
5953 If UPDATE_EDGE_COUNT_P is true, the edge counts on both CFGs is
5954 updated to reflect the moved edges.
5956 The local variables are remapped to new instances, VARS_MAP is used
5957 to record the mapping. */
5960 move_block_to_fn (struct function *dest_cfun, basic_block bb,
5961 basic_block after, bool update_edge_count_p,
5962 struct move_stmt_d *d, int eh_offset)
5964 struct control_flow_graph *cfg;
5967 gimple_stmt_iterator si;
5968 unsigned old_len, new_len;
5970 /* Remove BB from dominance structures. */
5971 delete_from_dominance_info (CDI_DOMINATORS, bb);
5973 remove_bb_from_loops (bb);
5975 /* Link BB to the new linked list. */
5976 move_block_after (bb, after);
5978 /* Update the edge count in the corresponding flowgraphs. */
5979 if (update_edge_count_p)
5980 FOR_EACH_EDGE (e, ei, bb->succs)
5982 cfun->cfg->x_n_edges--;
5983 dest_cfun->cfg->x_n_edges++;
5986 /* Remove BB from the original basic block array. */
5987 VEC_replace (basic_block, cfun->cfg->x_basic_block_info, bb->index, NULL);
5988 cfun->cfg->x_n_basic_blocks--;
5990 /* Grow DEST_CFUN's basic block array if needed. */
5991 cfg = dest_cfun->cfg;
5992 cfg->x_n_basic_blocks++;
5993 if (bb->index >= cfg->x_last_basic_block)
5994 cfg->x_last_basic_block = bb->index + 1;
5996 old_len = VEC_length (basic_block, cfg->x_basic_block_info);
5997 if ((unsigned) cfg->x_last_basic_block >= old_len)
5999 new_len = cfg->x_last_basic_block + (cfg->x_last_basic_block + 3) / 4;
6000 VEC_safe_grow_cleared (basic_block, gc, cfg->x_basic_block_info,
6004 VEC_replace (basic_block, cfg->x_basic_block_info,
6007 /* Remap the variables in phi nodes. */
6008 for (si = gsi_start_phis (bb); !gsi_end_p (si); )
6010 gimple phi = gsi_stmt (si);
6012 tree op = PHI_RESULT (phi);
6015 if (!is_gimple_reg (op))
6017 /* Remove the phi nodes for virtual operands (alias analysis will be
6018 run for the new function, anyway). */
6019 remove_phi_node (&si, true);
6023 SET_PHI_RESULT (phi,
6024 replace_ssa_name (op, d->vars_map, dest_cfun->decl));
6025 FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
6027 op = USE_FROM_PTR (use);
6028 if (TREE_CODE (op) == SSA_NAME)
6029 SET_USE (use, replace_ssa_name (op, d->vars_map, dest_cfun->decl));
6035 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
6037 gimple stmt = gsi_stmt (si);
6039 struct walk_stmt_info wi;
6041 memset (&wi, 0, sizeof (wi));
6043 walk_gimple_stmt (&si, move_stmt_r, move_stmt_op, &wi);
6045 if (gimple_code (stmt) == GIMPLE_LABEL)
6047 tree label = gimple_label_label (stmt);
6048 int uid = LABEL_DECL_UID (label);
6050 gcc_assert (uid > -1);
6052 old_len = VEC_length (basic_block, cfg->x_label_to_block_map);
6053 if (old_len <= (unsigned) uid)
6055 new_len = 3 * uid / 2 + 1;
6056 VEC_safe_grow_cleared (basic_block, gc,
6057 cfg->x_label_to_block_map, new_len);
6060 VEC_replace (basic_block, cfg->x_label_to_block_map, uid, bb);
6061 VEC_replace (basic_block, cfun->cfg->x_label_to_block_map, uid, NULL);
6063 gcc_assert (DECL_CONTEXT (label) == dest_cfun->decl);
6065 if (uid >= dest_cfun->cfg->last_label_uid)
6066 dest_cfun->cfg->last_label_uid = uid + 1;
6068 else if (gimple_code (stmt) == GIMPLE_RESX && eh_offset != 0)
6069 gimple_resx_set_region (stmt, gimple_resx_region (stmt) + eh_offset);
6071 region = lookup_stmt_eh_region (stmt);
6074 add_stmt_to_eh_region_fn (dest_cfun, stmt, region + eh_offset);
6075 remove_stmt_from_eh_region (stmt);
6076 gimple_duplicate_stmt_histograms (dest_cfun, stmt, cfun, stmt);
6077 gimple_remove_stmt_histograms (cfun, stmt);
6080 /* We cannot leave any operands allocated from the operand caches of
6081 the current function. */
6082 free_stmt_operands (stmt);
6083 push_cfun (dest_cfun);
6088 FOR_EACH_EDGE (e, ei, bb->succs)
6091 tree block = e->goto_block;
6092 if (d->orig_block == NULL_TREE
6093 || block == d->orig_block)
6094 e->goto_block = d->new_block;
6095 #ifdef ENABLE_CHECKING
6096 else if (block != d->new_block)
6098 while (block && block != d->orig_block)
6099 block = BLOCK_SUPERCONTEXT (block);
6106 /* Examine the statements in BB (which is in SRC_CFUN); find and return
6107 the outermost EH region. Use REGION as the incoming base EH region. */
6110 find_outermost_region_in_block (struct function *src_cfun,
6111 basic_block bb, int region)
6113 gimple_stmt_iterator si;
6115 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
6117 gimple stmt = gsi_stmt (si);
6120 if (gimple_code (stmt) == GIMPLE_RESX)
6121 stmt_region = gimple_resx_region (stmt);
6123 stmt_region = lookup_stmt_eh_region_fn (src_cfun, stmt);
6124 if (stmt_region > 0)
6127 region = stmt_region;
6128 else if (stmt_region != region)
6130 region = eh_region_outermost (src_cfun, stmt_region, region);
6131 gcc_assert (region != -1);
6140 new_label_mapper (tree decl, void *data)
6142 htab_t hash = (htab_t) data;
6146 gcc_assert (TREE_CODE (decl) == LABEL_DECL);
6148 m = XNEW (struct tree_map);
6149 m->hash = DECL_UID (decl);
6150 m->base.from = decl;
6151 m->to = create_artificial_label (UNKNOWN_LOCATION);
6152 LABEL_DECL_UID (m->to) = LABEL_DECL_UID (decl);
6153 if (LABEL_DECL_UID (m->to) >= cfun->cfg->last_label_uid)
6154 cfun->cfg->last_label_uid = LABEL_DECL_UID (m->to) + 1;
6156 slot = htab_find_slot_with_hash (hash, m, m->hash, INSERT);
6157 gcc_assert (*slot == NULL);
6164 /* Change DECL_CONTEXT of all BLOCK_VARS in block, including
6168 replace_block_vars_by_duplicates (tree block, struct pointer_map_t *vars_map,
6173 for (tp = &BLOCK_VARS (block); *tp; tp = &TREE_CHAIN (*tp))
6176 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != CONST_DECL)
6178 replace_by_duplicate_decl (&t, vars_map, to_context);
6181 if (TREE_CODE (*tp) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (*tp))
6183 SET_DECL_VALUE_EXPR (t, DECL_VALUE_EXPR (*tp));
6184 DECL_HAS_VALUE_EXPR_P (t) = 1;
6186 TREE_CHAIN (t) = TREE_CHAIN (*tp);
6191 for (block = BLOCK_SUBBLOCKS (block); block; block = BLOCK_CHAIN (block))
6192 replace_block_vars_by_duplicates (block, vars_map, to_context);
6195 /* Move a single-entry, single-exit region delimited by ENTRY_BB and
6196 EXIT_BB to function DEST_CFUN. The whole region is replaced by a
6197 single basic block in the original CFG and the new basic block is
6198 returned. DEST_CFUN must not have a CFG yet.
6200 Note that the region need not be a pure SESE region. Blocks inside
6201 the region may contain calls to abort/exit. The only restriction
6202 is that ENTRY_BB should be the only entry point and it must
6205 Change TREE_BLOCK of all statements in ORIG_BLOCK to the new
6206 functions outermost BLOCK, move all subblocks of ORIG_BLOCK
6207 to the new function.
6209 All local variables referenced in the region are assumed to be in
6210 the corresponding BLOCK_VARS and unexpanded variable lists
6211 associated with DEST_CFUN. */
6214 move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb,
6215 basic_block exit_bb, tree orig_block)
6217 VEC(basic_block,heap) *bbs, *dom_bbs;
6218 basic_block dom_entry = get_immediate_dominator (CDI_DOMINATORS, entry_bb);
6219 basic_block after, bb, *entry_pred, *exit_succ, abb;
6220 struct function *saved_cfun = cfun;
6221 int *entry_flag, *exit_flag, eh_offset;
6222 unsigned *entry_prob, *exit_prob;
6223 unsigned i, num_entry_edges, num_exit_edges;
6226 htab_t new_label_map;
6227 struct pointer_map_t *vars_map;
6228 struct loop *loop = entry_bb->loop_father;
6229 struct move_stmt_d d;
6231 /* If ENTRY does not strictly dominate EXIT, this cannot be an SESE
6233 gcc_assert (entry_bb != exit_bb
6235 || dominated_by_p (CDI_DOMINATORS, exit_bb, entry_bb)));
6237 /* Collect all the blocks in the region. Manually add ENTRY_BB
6238 because it won't be added by dfs_enumerate_from. */
6240 VEC_safe_push (basic_block, heap, bbs, entry_bb);
6241 gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs);
6243 /* The blocks that used to be dominated by something in BBS will now be
6244 dominated by the new block. */
6245 dom_bbs = get_dominated_by_region (CDI_DOMINATORS,
6246 VEC_address (basic_block, bbs),
6247 VEC_length (basic_block, bbs));
6249 /* Detach ENTRY_BB and EXIT_BB from CFUN->CFG. We need to remember
6250 the predecessor edges to ENTRY_BB and the successor edges to
6251 EXIT_BB so that we can re-attach them to the new basic block that
6252 will replace the region. */
6253 num_entry_edges = EDGE_COUNT (entry_bb->preds);
6254 entry_pred = (basic_block *) xcalloc (num_entry_edges, sizeof (basic_block));
6255 entry_flag = (int *) xcalloc (num_entry_edges, sizeof (int));
6256 entry_prob = XNEWVEC (unsigned, num_entry_edges);
6258 for (ei = ei_start (entry_bb->preds); (e = ei_safe_edge (ei)) != NULL;)
6260 entry_prob[i] = e->probability;
6261 entry_flag[i] = e->flags;
6262 entry_pred[i++] = e->src;
6268 num_exit_edges = EDGE_COUNT (exit_bb->succs);
6269 exit_succ = (basic_block *) xcalloc (num_exit_edges,
6270 sizeof (basic_block));
6271 exit_flag = (int *) xcalloc (num_exit_edges, sizeof (int));
6272 exit_prob = XNEWVEC (unsigned, num_exit_edges);
6274 for (ei = ei_start (exit_bb->succs); (e = ei_safe_edge (ei)) != NULL;)
6276 exit_prob[i] = e->probability;
6277 exit_flag[i] = e->flags;
6278 exit_succ[i++] = e->dest;
6290 /* Switch context to the child function to initialize DEST_FN's CFG. */
6291 gcc_assert (dest_cfun->cfg == NULL);
6292 push_cfun (dest_cfun);
6294 init_empty_tree_cfg ();
6296 /* Initialize EH information for the new function. */
6298 new_label_map = NULL;
6303 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6304 region = find_outermost_region_in_block (saved_cfun, bb, region);
6306 init_eh_for_function ();
6309 new_label_map = htab_create (17, tree_map_hash, tree_map_eq, free);
6310 eh_offset = duplicate_eh_regions (saved_cfun, new_label_mapper,
6311 new_label_map, region, 0);
6317 /* Move blocks from BBS into DEST_CFUN. */
6318 gcc_assert (VEC_length (basic_block, bbs) >= 2);
6319 after = dest_cfun->cfg->x_entry_block_ptr;
6320 vars_map = pointer_map_create ();
6322 memset (&d, 0, sizeof (d));
6323 d.vars_map = vars_map;
6324 d.from_context = cfun->decl;
6325 d.to_context = dest_cfun->decl;
6326 d.new_label_map = new_label_map;
6327 d.remap_decls_p = true;
6328 d.orig_block = orig_block;
6329 d.new_block = DECL_INITIAL (dest_cfun->decl);
6331 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6333 /* No need to update edge counts on the last block. It has
6334 already been updated earlier when we detached the region from
6335 the original CFG. */
6336 move_block_to_fn (dest_cfun, bb, after, bb != exit_bb, &d, eh_offset);
6340 /* Rewire BLOCK_SUBBLOCKS of orig_block. */
6344 gcc_assert (BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6346 BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6347 = BLOCK_SUBBLOCKS (orig_block);
6348 for (block = BLOCK_SUBBLOCKS (orig_block);
6349 block; block = BLOCK_CHAIN (block))
6350 BLOCK_SUPERCONTEXT (block) = DECL_INITIAL (dest_cfun->decl);
6351 BLOCK_SUBBLOCKS (orig_block) = NULL_TREE;
6354 replace_block_vars_by_duplicates (DECL_INITIAL (dest_cfun->decl),
6355 vars_map, dest_cfun->decl);
6358 htab_delete (new_label_map);
6359 pointer_map_destroy (vars_map);
6361 /* Rewire the entry and exit blocks. The successor to the entry
6362 block turns into the successor of DEST_FN's ENTRY_BLOCK_PTR in
6363 the child function. Similarly, the predecessor of DEST_FN's
6364 EXIT_BLOCK_PTR turns into the predecessor of EXIT_BLOCK_PTR. We
6365 need to switch CFUN between DEST_CFUN and SAVED_CFUN so that the
6366 various CFG manipulation function get to the right CFG.
6368 FIXME, this is silly. The CFG ought to become a parameter to
6370 push_cfun (dest_cfun);
6371 make_edge (ENTRY_BLOCK_PTR, entry_bb, EDGE_FALLTHRU);
6373 make_edge (exit_bb, EXIT_BLOCK_PTR, 0);
6376 /* Back in the original function, the SESE region has disappeared,
6377 create a new basic block in its place. */
6378 bb = create_empty_bb (entry_pred[0]);
6380 add_bb_to_loop (bb, loop);
6381 for (i = 0; i < num_entry_edges; i++)
6383 e = make_edge (entry_pred[i], bb, entry_flag[i]);
6384 e->probability = entry_prob[i];
6387 for (i = 0; i < num_exit_edges; i++)
6389 e = make_edge (bb, exit_succ[i], exit_flag[i]);
6390 e->probability = exit_prob[i];
6393 set_immediate_dominator (CDI_DOMINATORS, bb, dom_entry);
6394 for (i = 0; VEC_iterate (basic_block, dom_bbs, i, abb); i++)
6395 set_immediate_dominator (CDI_DOMINATORS, abb, bb);
6396 VEC_free (basic_block, heap, dom_bbs);
6407 VEC_free (basic_block, heap, bbs);
6413 /* Dump FUNCTION_DECL FN to file FILE using FLAGS (see TDF_* in tree-pass.h)
6417 dump_function_to_file (tree fn, FILE *file, int flags)
6419 tree arg, vars, var;
6420 struct function *dsf;
6421 bool ignore_topmost_bind = false, any_var = false;
6425 fprintf (file, "%s (", lang_hooks.decl_printable_name (fn, 2));
6427 arg = DECL_ARGUMENTS (fn);
6430 print_generic_expr (file, TREE_TYPE (arg), dump_flags);
6431 fprintf (file, " ");
6432 print_generic_expr (file, arg, dump_flags);
6433 if (flags & TDF_VERBOSE)
6434 print_node (file, "", arg, 4);
6435 if (TREE_CHAIN (arg))
6436 fprintf (file, ", ");
6437 arg = TREE_CHAIN (arg);
6439 fprintf (file, ")\n");
6441 if (flags & TDF_VERBOSE)
6442 print_node (file, "", fn, 2);
6444 dsf = DECL_STRUCT_FUNCTION (fn);
6445 if (dsf && (flags & TDF_DETAILS))
6446 dump_eh_tree (file, dsf);
6448 if (flags & TDF_RAW && !gimple_has_body_p (fn))
6450 dump_node (fn, TDF_SLIM | flags, file);
6454 /* Switch CFUN to point to FN. */
6455 push_cfun (DECL_STRUCT_FUNCTION (fn));
6457 /* When GIMPLE is lowered, the variables are no longer available in
6458 BIND_EXPRs, so display them separately. */
6459 if (cfun && cfun->decl == fn && cfun->local_decls)
6461 ignore_topmost_bind = true;
6463 fprintf (file, "{\n");
6464 for (vars = cfun->local_decls; vars; vars = TREE_CHAIN (vars))
6466 var = TREE_VALUE (vars);
6468 print_generic_decl (file, var, flags);
6469 if (flags & TDF_VERBOSE)
6470 print_node (file, "", var, 4);
6471 fprintf (file, "\n");
6477 if (cfun && cfun->decl == fn && cfun->cfg && basic_block_info)
6479 /* If the CFG has been built, emit a CFG-based dump. */
6480 check_bb_profile (ENTRY_BLOCK_PTR, file);
6481 if (!ignore_topmost_bind)
6482 fprintf (file, "{\n");
6484 if (any_var && n_basic_blocks)
6485 fprintf (file, "\n");
6488 gimple_dump_bb (bb, file, 2, flags);
6490 fprintf (file, "}\n");
6491 check_bb_profile (EXIT_BLOCK_PTR, file);
6493 else if (DECL_SAVED_TREE (fn) == NULL)
6495 /* The function is now in GIMPLE form but the CFG has not been
6496 built yet. Emit the single sequence of GIMPLE statements
6497 that make up its body. */
6498 gimple_seq body = gimple_body (fn);
6500 if (gimple_seq_first_stmt (body)
6501 && gimple_seq_first_stmt (body) == gimple_seq_last_stmt (body)
6502 && gimple_code (gimple_seq_first_stmt (body)) == GIMPLE_BIND)
6503 print_gimple_seq (file, body, 0, flags);
6506 if (!ignore_topmost_bind)
6507 fprintf (file, "{\n");
6510 fprintf (file, "\n");
6512 print_gimple_seq (file, body, 2, flags);
6513 fprintf (file, "}\n");
6520 /* Make a tree based dump. */
6521 chain = DECL_SAVED_TREE (fn);
6523 if (chain && TREE_CODE (chain) == BIND_EXPR)
6525 if (ignore_topmost_bind)
6527 chain = BIND_EXPR_BODY (chain);
6535 if (!ignore_topmost_bind)
6536 fprintf (file, "{\n");
6541 fprintf (file, "\n");
6543 print_generic_stmt_indented (file, chain, flags, indent);
6544 if (ignore_topmost_bind)
6545 fprintf (file, "}\n");
6548 fprintf (file, "\n\n");
6555 /* Dump FUNCTION_DECL FN to stderr using FLAGS (see TDF_* in tree.h) */
6558 debug_function (tree fn, int flags)
6560 dump_function_to_file (fn, stderr, flags);
6564 /* Print on FILE the indexes for the predecessors of basic_block BB. */
6567 print_pred_bbs (FILE *file, basic_block bb)
6572 FOR_EACH_EDGE (e, ei, bb->preds)
6573 fprintf (file, "bb_%d ", e->src->index);
6577 /* Print on FILE the indexes for the successors of basic_block BB. */
6580 print_succ_bbs (FILE *file, basic_block bb)
6585 FOR_EACH_EDGE (e, ei, bb->succs)
6586 fprintf (file, "bb_%d ", e->dest->index);
6589 /* Print to FILE the basic block BB following the VERBOSITY level. */
6592 print_loops_bb (FILE *file, basic_block bb, int indent, int verbosity)
6594 char *s_indent = (char *) alloca ((size_t) indent + 1);
6595 memset ((void *) s_indent, ' ', (size_t) indent);
6596 s_indent[indent] = '\0';
6598 /* Print basic_block's header. */
6601 fprintf (file, "%s bb_%d (preds = {", s_indent, bb->index);
6602 print_pred_bbs (file, bb);
6603 fprintf (file, "}, succs = {");
6604 print_succ_bbs (file, bb);
6605 fprintf (file, "})\n");
6608 /* Print basic_block's body. */
6611 fprintf (file, "%s {\n", s_indent);
6612 gimple_dump_bb (bb, file, indent + 4, TDF_VOPS|TDF_MEMSYMS);
6613 fprintf (file, "%s }\n", s_indent);
6617 static void print_loop_and_siblings (FILE *, struct loop *, int, int);
6619 /* Pretty print LOOP on FILE, indented INDENT spaces. Following
6620 VERBOSITY level this outputs the contents of the loop, or just its
6624 print_loop (FILE *file, struct loop *loop, int indent, int verbosity)
6632 s_indent = (char *) alloca ((size_t) indent + 1);
6633 memset ((void *) s_indent, ' ', (size_t) indent);
6634 s_indent[indent] = '\0';
6636 /* Print loop's header. */
6637 fprintf (file, "%sloop_%d (header = %d, latch = %d", s_indent,
6638 loop->num, loop->header->index, loop->latch->index);
6639 fprintf (file, ", niter = ");
6640 print_generic_expr (file, loop->nb_iterations, 0);
6642 if (loop->any_upper_bound)
6644 fprintf (file, ", upper_bound = ");
6645 dump_double_int (file, loop->nb_iterations_upper_bound, true);
6648 if (loop->any_estimate)
6650 fprintf (file, ", estimate = ");
6651 dump_double_int (file, loop->nb_iterations_estimate, true);
6653 fprintf (file, ")\n");
6655 /* Print loop's body. */
6658 fprintf (file, "%s{\n", s_indent);
6660 if (bb->loop_father == loop)
6661 print_loops_bb (file, bb, indent, verbosity);
6663 print_loop_and_siblings (file, loop->inner, indent + 2, verbosity);
6664 fprintf (file, "%s}\n", s_indent);
6668 /* Print the LOOP and its sibling loops on FILE, indented INDENT
6669 spaces. Following VERBOSITY level this outputs the contents of the
6670 loop, or just its structure. */
6673 print_loop_and_siblings (FILE *file, struct loop *loop, int indent, int verbosity)
6678 print_loop (file, loop, indent, verbosity);
6679 print_loop_and_siblings (file, loop->next, indent, verbosity);
6682 /* Follow a CFG edge from the entry point of the program, and on entry
6683 of a loop, pretty print the loop structure on FILE. */
6686 print_loops (FILE *file, int verbosity)
6690 bb = ENTRY_BLOCK_PTR;
6691 if (bb && bb->loop_father)
6692 print_loop_and_siblings (file, bb->loop_father, 0, verbosity);
6696 /* Debugging loops structure at tree level, at some VERBOSITY level. */
6699 debug_loops (int verbosity)
6701 print_loops (stderr, verbosity);
6704 /* Print on stderr the code of LOOP, at some VERBOSITY level. */
6707 debug_loop (struct loop *loop, int verbosity)
6709 print_loop (stderr, loop, 0, verbosity);
6712 /* Print on stderr the code of loop number NUM, at some VERBOSITY
6716 debug_loop_num (unsigned num, int verbosity)
6718 debug_loop (get_loop (num), verbosity);
6721 /* Return true if BB ends with a call, possibly followed by some
6722 instructions that must stay with the call. Return false,
6726 gimple_block_ends_with_call_p (basic_block bb)
6728 gimple_stmt_iterator gsi = gsi_last_nondebug_bb (bb);
6729 return is_gimple_call (gsi_stmt (gsi));
6733 /* Return true if BB ends with a conditional branch. Return false,
6737 gimple_block_ends_with_condjump_p (const_basic_block bb)
6739 gimple stmt = last_stmt (CONST_CAST_BB (bb));
6740 return (stmt && gimple_code (stmt) == GIMPLE_COND);
6744 /* Return true if we need to add fake edge to exit at statement T.
6745 Helper function for gimple_flow_call_edges_add. */
6748 need_fake_edge_p (gimple t)
6750 tree fndecl = NULL_TREE;
6753 /* NORETURN and LONGJMP calls already have an edge to exit.
6754 CONST and PURE calls do not need one.
6755 We don't currently check for CONST and PURE here, although
6756 it would be a good idea, because those attributes are
6757 figured out from the RTL in mark_constant_function, and
6758 the counter incrementation code from -fprofile-arcs
6759 leads to different results from -fbranch-probabilities. */
6760 if (is_gimple_call (t))
6762 fndecl = gimple_call_fndecl (t);
6763 call_flags = gimple_call_flags (t);
6766 if (is_gimple_call (t)
6768 && DECL_BUILT_IN (fndecl)
6769 && (call_flags & ECF_NOTHROW)
6770 && !(call_flags & ECF_RETURNS_TWICE)
6771 /* fork() doesn't really return twice, but the effect of
6772 wrapping it in __gcov_fork() which calls __gcov_flush()
6773 and clears the counters before forking has the same
6774 effect as returning twice. Force a fake edge. */
6775 && !(DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6776 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_FORK))
6779 if (is_gimple_call (t)
6780 && !(call_flags & ECF_NORETURN))
6783 if (gimple_code (t) == GIMPLE_ASM
6784 && (gimple_asm_volatile_p (t) || gimple_asm_input_p (t)))
6791 /* Add fake edges to the function exit for any non constant and non
6792 noreturn calls, volatile inline assembly in the bitmap of blocks
6793 specified by BLOCKS or to the whole CFG if BLOCKS is zero. Return
6794 the number of blocks that were split.
6796 The goal is to expose cases in which entering a basic block does
6797 not imply that all subsequent instructions must be executed. */
6800 gimple_flow_call_edges_add (sbitmap blocks)
6803 int blocks_split = 0;
6804 int last_bb = last_basic_block;
6805 bool check_last_block = false;
6807 if (n_basic_blocks == NUM_FIXED_BLOCKS)
6811 check_last_block = true;
6813 check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index);
6815 /* In the last basic block, before epilogue generation, there will be
6816 a fallthru edge to EXIT. Special care is required if the last insn
6817 of the last basic block is a call because make_edge folds duplicate
6818 edges, which would result in the fallthru edge also being marked
6819 fake, which would result in the fallthru edge being removed by
6820 remove_fake_edges, which would result in an invalid CFG.
6822 Moreover, we can't elide the outgoing fake edge, since the block
6823 profiler needs to take this into account in order to solve the minimal
6824 spanning tree in the case that the call doesn't return.
6826 Handle this by adding a dummy instruction in a new last basic block. */
6827 if (check_last_block)
6829 basic_block bb = EXIT_BLOCK_PTR->prev_bb;
6830 gimple_stmt_iterator gsi = gsi_last_bb (bb);
6833 if (!gsi_end_p (gsi))
6836 if (t && need_fake_edge_p (t))
6840 e = find_edge (bb, EXIT_BLOCK_PTR);
6843 gsi_insert_on_edge (e, gimple_build_nop ());
6844 gsi_commit_edge_inserts ();
6849 /* Now add fake edges to the function exit for any non constant
6850 calls since there is no way that we can determine if they will
6852 for (i = 0; i < last_bb; i++)
6854 basic_block bb = BASIC_BLOCK (i);
6855 gimple_stmt_iterator gsi;
6856 gimple stmt, last_stmt;
6861 if (blocks && !TEST_BIT (blocks, i))
6864 gsi = gsi_last_bb (bb);
6865 if (!gsi_end_p (gsi))
6867 last_stmt = gsi_stmt (gsi);
6870 stmt = gsi_stmt (gsi);
6871 if (need_fake_edge_p (stmt))
6875 /* The handling above of the final block before the
6876 epilogue should be enough to verify that there is
6877 no edge to the exit block in CFG already.
6878 Calling make_edge in such case would cause us to
6879 mark that edge as fake and remove it later. */
6880 #ifdef ENABLE_CHECKING
6881 if (stmt == last_stmt)
6883 e = find_edge (bb, EXIT_BLOCK_PTR);
6884 gcc_assert (e == NULL);
6888 /* Note that the following may create a new basic block
6889 and renumber the existing basic blocks. */
6890 if (stmt != last_stmt)
6892 e = split_block (bb, stmt);
6896 make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE);
6900 while (!gsi_end_p (gsi));
6905 verify_flow_info ();
6907 return blocks_split;
6910 /* Purge dead abnormal call edges from basic block BB. */
6913 gimple_purge_dead_abnormal_call_edges (basic_block bb)
6915 bool changed = gimple_purge_dead_eh_edges (bb);
6917 if (cfun->has_nonlocal_label)
6919 gimple stmt = last_stmt (bb);
6923 if (!(stmt && stmt_can_make_abnormal_goto (stmt)))
6924 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6926 if (e->flags & EDGE_ABNORMAL)
6935 /* See gimple_purge_dead_eh_edges below. */
6937 free_dominance_info (CDI_DOMINATORS);
6943 /* Removes edge E and all the blocks dominated by it, and updates dominance
6944 information. The IL in E->src needs to be updated separately.
6945 If dominance info is not available, only the edge E is removed.*/
6948 remove_edge_and_dominated_blocks (edge e)
6950 VEC (basic_block, heap) *bbs_to_remove = NULL;
6951 VEC (basic_block, heap) *bbs_to_fix_dom = NULL;
6955 bool none_removed = false;
6957 basic_block bb, dbb;
6960 if (!dom_info_available_p (CDI_DOMINATORS))
6966 /* No updating is needed for edges to exit. */
6967 if (e->dest == EXIT_BLOCK_PTR)
6969 if (cfgcleanup_altered_bbs)
6970 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6975 /* First, we find the basic blocks to remove. If E->dest has a predecessor
6976 that is not dominated by E->dest, then this set is empty. Otherwise,
6977 all the basic blocks dominated by E->dest are removed.
6979 Also, to DF_IDOM we store the immediate dominators of the blocks in
6980 the dominance frontier of E (i.e., of the successors of the
6981 removed blocks, if there are any, and of E->dest otherwise). */
6982 FOR_EACH_EDGE (f, ei, e->dest->preds)
6987 if (!dominated_by_p (CDI_DOMINATORS, f->src, e->dest))
6989 none_removed = true;
6994 df = BITMAP_ALLOC (NULL);
6995 df_idom = BITMAP_ALLOC (NULL);
6998 bitmap_set_bit (df_idom,
6999 get_immediate_dominator (CDI_DOMINATORS, e->dest)->index);
7002 bbs_to_remove = get_all_dominated_blocks (CDI_DOMINATORS, e->dest);
7003 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
7005 FOR_EACH_EDGE (f, ei, bb->succs)
7007 if (f->dest != EXIT_BLOCK_PTR)
7008 bitmap_set_bit (df, f->dest->index);
7011 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
7012 bitmap_clear_bit (df, bb->index);
7014 EXECUTE_IF_SET_IN_BITMAP (df, 0, i, bi)
7016 bb = BASIC_BLOCK (i);
7017 bitmap_set_bit (df_idom,
7018 get_immediate_dominator (CDI_DOMINATORS, bb)->index);
7022 if (cfgcleanup_altered_bbs)
7024 /* Record the set of the altered basic blocks. */
7025 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
7026 bitmap_ior_into (cfgcleanup_altered_bbs, df);
7029 /* Remove E and the cancelled blocks. */
7034 /* Walk backwards so as to get a chance to substitute all
7035 released DEFs into debug stmts. See
7036 eliminate_unnecessary_stmts() in tree-ssa-dce.c for more
7038 for (i = VEC_length (basic_block, bbs_to_remove); i-- > 0; )
7039 delete_basic_block (VEC_index (basic_block, bbs_to_remove, i));
7042 /* Update the dominance information. The immediate dominator may change only
7043 for blocks whose immediate dominator belongs to DF_IDOM:
7045 Suppose that idom(X) = Y before removal of E and idom(X) != Y after the
7046 removal. Let Z the arbitrary block such that idom(Z) = Y and
7047 Z dominates X after the removal. Before removal, there exists a path P
7048 from Y to X that avoids Z. Let F be the last edge on P that is
7049 removed, and let W = F->dest. Before removal, idom(W) = Y (since Y
7050 dominates W, and because of P, Z does not dominate W), and W belongs to
7051 the dominance frontier of E. Therefore, Y belongs to DF_IDOM. */
7052 EXECUTE_IF_SET_IN_BITMAP (df_idom, 0, i, bi)
7054 bb = BASIC_BLOCK (i);
7055 for (dbb = first_dom_son (CDI_DOMINATORS, bb);
7057 dbb = next_dom_son (CDI_DOMINATORS, dbb))
7058 VEC_safe_push (basic_block, heap, bbs_to_fix_dom, dbb);
7061 iterate_fix_dominators (CDI_DOMINATORS, bbs_to_fix_dom, true);
7064 BITMAP_FREE (df_idom);
7065 VEC_free (basic_block, heap, bbs_to_remove);
7066 VEC_free (basic_block, heap, bbs_to_fix_dom);
7069 /* Purge dead EH edges from basic block BB. */
7072 gimple_purge_dead_eh_edges (basic_block bb)
7074 bool changed = false;
7077 gimple stmt = last_stmt (bb);
7079 if (stmt && stmt_can_throw_internal (stmt))
7082 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
7084 if (e->flags & EDGE_EH)
7086 remove_edge_and_dominated_blocks (e);
7097 gimple_purge_all_dead_eh_edges (const_bitmap blocks)
7099 bool changed = false;
7103 EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
7105 basic_block bb = BASIC_BLOCK (i);
7107 /* Earlier gimple_purge_dead_eh_edges could have removed
7108 this basic block already. */
7109 gcc_assert (bb || changed);
7111 changed |= gimple_purge_dead_eh_edges (bb);
7117 /* This function is called whenever a new edge is created or
7121 gimple_execute_on_growing_pred (edge e)
7123 basic_block bb = e->dest;
7126 reserve_phi_args_for_new_edge (bb);
7129 /* This function is called immediately before edge E is removed from
7130 the edge vector E->dest->preds. */
7133 gimple_execute_on_shrinking_pred (edge e)
7135 if (phi_nodes (e->dest))
7136 remove_phi_args (e);
7139 /*---------------------------------------------------------------------------
7140 Helper functions for Loop versioning
7141 ---------------------------------------------------------------------------*/
7143 /* Adjust phi nodes for 'first' basic block. 'second' basic block is a copy
7144 of 'first'. Both of them are dominated by 'new_head' basic block. When
7145 'new_head' was created by 'second's incoming edge it received phi arguments
7146 on the edge by split_edge(). Later, additional edge 'e' was created to
7147 connect 'new_head' and 'first'. Now this routine adds phi args on this
7148 additional edge 'e' that new_head to second edge received as part of edge
7152 gimple_lv_adjust_loop_header_phi (basic_block first, basic_block second,
7153 basic_block new_head, edge e)
7156 gimple_stmt_iterator psi1, psi2;
7158 edge e2 = find_edge (new_head, second);
7160 /* Because NEW_HEAD has been created by splitting SECOND's incoming
7161 edge, we should always have an edge from NEW_HEAD to SECOND. */
7162 gcc_assert (e2 != NULL);
7164 /* Browse all 'second' basic block phi nodes and add phi args to
7165 edge 'e' for 'first' head. PHI args are always in correct order. */
7167 for (psi2 = gsi_start_phis (second),
7168 psi1 = gsi_start_phis (first);
7169 !gsi_end_p (psi2) && !gsi_end_p (psi1);
7170 gsi_next (&psi2), gsi_next (&psi1))
7172 phi1 = gsi_stmt (psi1);
7173 phi2 = gsi_stmt (psi2);
7174 def = PHI_ARG_DEF (phi2, e2->dest_idx);
7175 add_phi_arg (phi1, def, e, gimple_phi_arg_location_from_edge (phi2, e2));
7180 /* Adds a if else statement to COND_BB with condition COND_EXPR.
7181 SECOND_HEAD is the destination of the THEN and FIRST_HEAD is
7182 the destination of the ELSE part. */
7185 gimple_lv_add_condition_to_bb (basic_block first_head ATTRIBUTE_UNUSED,
7186 basic_block second_head ATTRIBUTE_UNUSED,
7187 basic_block cond_bb, void *cond_e)
7189 gimple_stmt_iterator gsi;
7190 gimple new_cond_expr;
7191 tree cond_expr = (tree) cond_e;
7194 /* Build new conditional expr */
7195 new_cond_expr = gimple_build_cond_from_tree (cond_expr,
7196 NULL_TREE, NULL_TREE);
7198 /* Add new cond in cond_bb. */
7199 gsi = gsi_last_bb (cond_bb);
7200 gsi_insert_after (&gsi, new_cond_expr, GSI_NEW_STMT);
7202 /* Adjust edges appropriately to connect new head with first head
7203 as well as second head. */
7204 e0 = single_succ_edge (cond_bb);
7205 e0->flags &= ~EDGE_FALLTHRU;
7206 e0->flags |= EDGE_FALSE_VALUE;
7209 struct cfg_hooks gimple_cfg_hooks = {
7211 gimple_verify_flow_info,
7212 gimple_dump_bb, /* dump_bb */
7213 create_bb, /* create_basic_block */
7214 gimple_redirect_edge_and_branch, /* redirect_edge_and_branch */
7215 gimple_redirect_edge_and_branch_force, /* redirect_edge_and_branch_force */
7216 gimple_can_remove_branch_p, /* can_remove_branch_p */
7217 remove_bb, /* delete_basic_block */
7218 gimple_split_block, /* split_block */
7219 gimple_move_block_after, /* move_block_after */
7220 gimple_can_merge_blocks_p, /* can_merge_blocks_p */
7221 gimple_merge_blocks, /* merge_blocks */
7222 gimple_predict_edge, /* predict_edge */
7223 gimple_predicted_by_p, /* predicted_by_p */
7224 gimple_can_duplicate_bb_p, /* can_duplicate_block_p */
7225 gimple_duplicate_bb, /* duplicate_block */
7226 gimple_split_edge, /* split_edge */
7227 gimple_make_forwarder_block, /* make_forward_block */
7228 NULL, /* tidy_fallthru_edge */
7229 gimple_block_ends_with_call_p,/* block_ends_with_call_p */
7230 gimple_block_ends_with_condjump_p, /* block_ends_with_condjump_p */
7231 gimple_flow_call_edges_add, /* flow_call_edges_add */
7232 gimple_execute_on_growing_pred, /* execute_on_growing_pred */
7233 gimple_execute_on_shrinking_pred, /* execute_on_shrinking_pred */
7234 gimple_duplicate_loop_to_header_edge, /* duplicate loop for trees */
7235 gimple_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
7236 gimple_lv_adjust_loop_header_phi, /* lv_adjust_loop_header_phi*/
7237 extract_true_false_edges_from_block, /* extract_cond_bb_edges */
7238 flush_pending_stmts /* flush_pending_stmts */
7242 /* Split all critical edges. */
7245 split_critical_edges (void)
7251 /* split_edge can redirect edges out of SWITCH_EXPRs, which can get
7252 expensive. So we want to enable recording of edge to CASE_LABEL_EXPR
7253 mappings around the calls to split_edge. */
7254 start_recording_case_labels ();
7257 FOR_EACH_EDGE (e, ei, bb->succs)
7259 if (EDGE_CRITICAL_P (e) && !(e->flags & EDGE_ABNORMAL))
7261 /* PRE inserts statements to edges and expects that
7262 since split_critical_edges was done beforehand, committing edge
7263 insertions will not split more edges. In addition to critical
7264 edges we must split edges that have multiple successors and
7265 end by control flow statements, such as RESX.
7266 Go ahead and split them too. This matches the logic in
7267 gimple_find_edge_insert_loc. */
7268 else if ((!single_pred_p (e->dest)
7269 || !gimple_seq_empty_p (phi_nodes (e->dest))
7270 || e->dest == EXIT_BLOCK_PTR)
7271 && e->src != ENTRY_BLOCK_PTR
7272 && !(e->flags & EDGE_ABNORMAL))
7274 gimple_stmt_iterator gsi;
7276 gsi = gsi_last_bb (e->src);
7277 if (!gsi_end_p (gsi)
7278 && stmt_ends_bb_p (gsi_stmt (gsi))
7279 && gimple_code (gsi_stmt (gsi)) != GIMPLE_RETURN)
7284 end_recording_case_labels ();
7288 struct gimple_opt_pass pass_split_crit_edges =
7292 "crited", /* name */
7294 split_critical_edges, /* execute */
7297 0, /* static_pass_number */
7298 TV_TREE_SPLIT_EDGES, /* tv_id */
7299 PROP_cfg, /* properties required */
7300 PROP_no_crit_edges, /* properties_provided */
7301 0, /* properties_destroyed */
7302 0, /* todo_flags_start */
7303 TODO_dump_func | TODO_verify_flow /* todo_flags_finish */
7308 /* Build a ternary operation and gimplify it. Emit code before GSI.
7309 Return the gimple_val holding the result. */
7312 gimplify_build3 (gimple_stmt_iterator *gsi, enum tree_code code,
7313 tree type, tree a, tree b, tree c)
7316 location_t loc = gimple_location (gsi_stmt (*gsi));
7318 ret = fold_build3_loc (loc, code, type, a, b, c);
7321 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7325 /* Build a binary operation and gimplify it. Emit code before GSI.
7326 Return the gimple_val holding the result. */
7329 gimplify_build2 (gimple_stmt_iterator *gsi, enum tree_code code,
7330 tree type, tree a, tree b)
7334 ret = fold_build2_loc (gimple_location (gsi_stmt (*gsi)), code, type, a, b);
7337 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7341 /* Build a unary operation and gimplify it. Emit code before GSI.
7342 Return the gimple_val holding the result. */
7345 gimplify_build1 (gimple_stmt_iterator *gsi, enum tree_code code, tree type,
7350 ret = fold_build1_loc (gimple_location (gsi_stmt (*gsi)), code, type, a);
7353 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7359 /* Emit return warnings. */
7362 execute_warn_function_return (void)
7364 source_location location;
7369 /* If we have a path to EXIT, then we do return. */
7370 if (TREE_THIS_VOLATILE (cfun->decl)
7371 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0)
7373 location = UNKNOWN_LOCATION;
7374 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7376 last = last_stmt (e->src);
7377 if (gimple_code (last) == GIMPLE_RETURN
7378 && (location = gimple_location (last)) != UNKNOWN_LOCATION)
7381 if (location == UNKNOWN_LOCATION)
7382 location = cfun->function_end_locus;
7383 warning_at (location, 0, "%<noreturn%> function does return");
7386 /* If we see "return;" in some basic block, then we do reach the end
7387 without returning a value. */
7388 else if (warn_return_type
7389 && !TREE_NO_WARNING (cfun->decl)
7390 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0
7391 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (cfun->decl))))
7393 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7395 gimple last = last_stmt (e->src);
7396 if (gimple_code (last) == GIMPLE_RETURN
7397 && gimple_return_retval (last) == NULL
7398 && !gimple_no_warning_p (last))
7400 location = gimple_location (last);
7401 if (location == UNKNOWN_LOCATION)
7402 location = cfun->function_end_locus;
7403 warning_at (location, OPT_Wreturn_type, "control reaches end of non-void function");
7404 TREE_NO_WARNING (cfun->decl) = 1;
7413 /* Given a basic block B which ends with a conditional and has
7414 precisely two successors, determine which of the edges is taken if
7415 the conditional is true and which is taken if the conditional is
7416 false. Set TRUE_EDGE and FALSE_EDGE appropriately. */
7419 extract_true_false_edges_from_block (basic_block b,
7423 edge e = EDGE_SUCC (b, 0);
7425 if (e->flags & EDGE_TRUE_VALUE)
7428 *false_edge = EDGE_SUCC (b, 1);
7433 *true_edge = EDGE_SUCC (b, 1);
7437 struct gimple_opt_pass pass_warn_function_return =
7443 execute_warn_function_return, /* execute */
7446 0, /* static_pass_number */
7447 TV_NONE, /* tv_id */
7448 PROP_cfg, /* properties_required */
7449 0, /* properties_provided */
7450 0, /* properties_destroyed */
7451 0, /* todo_flags_start */
7452 0 /* todo_flags_finish */
7456 /* Emit noreturn warnings. */
7459 execute_warn_function_noreturn (void)
7461 if (warn_missing_noreturn
7462 && !TREE_THIS_VOLATILE (cfun->decl)
7463 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0
7464 && !lang_hooks.missing_noreturn_ok_p (cfun->decl))
7465 warning_at (DECL_SOURCE_LOCATION (cfun->decl), OPT_Wmissing_noreturn,
7466 "function might be possible candidate "
7467 "for attribute %<noreturn%>");
7471 struct gimple_opt_pass pass_warn_function_noreturn =
7477 execute_warn_function_noreturn, /* execute */
7480 0, /* static_pass_number */
7481 TV_NONE, /* tv_id */
7482 PROP_cfg, /* properties_required */
7483 0, /* properties_provided */
7484 0, /* properties_destroyed */
7485 0, /* todo_flags_start */
7486 0 /* todo_flags_finish */
7491 /* Walk a gimplified function and warn for functions whose return value is
7492 ignored and attribute((warn_unused_result)) is set. This is done before
7493 inlining, so we don't have to worry about that. */
7496 do_warn_unused_result (gimple_seq seq)
7499 gimple_stmt_iterator i;
7501 for (i = gsi_start (seq); !gsi_end_p (i); gsi_next (&i))
7503 gimple g = gsi_stmt (i);
7505 switch (gimple_code (g))
7508 do_warn_unused_result (gimple_bind_body (g));
7511 do_warn_unused_result (gimple_try_eval (g));
7512 do_warn_unused_result (gimple_try_cleanup (g));
7515 do_warn_unused_result (gimple_catch_handler (g));
7517 case GIMPLE_EH_FILTER:
7518 do_warn_unused_result (gimple_eh_filter_failure (g));
7522 if (gimple_call_lhs (g))
7525 /* This is a naked call, as opposed to a GIMPLE_CALL with an
7526 LHS. All calls whose value is ignored should be
7527 represented like this. Look for the attribute. */
7528 fdecl = gimple_call_fndecl (g);
7529 ftype = TREE_TYPE (TREE_TYPE (gimple_call_fn (g)));
7531 if (lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (ftype)))
7533 location_t loc = gimple_location (g);
7536 warning_at (loc, OPT_Wunused_result,
7537 "ignoring return value of %qD, "
7538 "declared with attribute warn_unused_result",
7541 warning_at (loc, OPT_Wunused_result,
7542 "ignoring return value of function "
7543 "declared with attribute warn_unused_result");
7548 /* Not a container, not a call, or a call whose value is used. */
7555 run_warn_unused_result (void)
7557 do_warn_unused_result (gimple_body (current_function_decl));
7562 gate_warn_unused_result (void)
7564 return flag_warn_unused_result;
7567 struct gimple_opt_pass pass_warn_unused_result =
7571 "*warn_unused_result", /* name */
7572 gate_warn_unused_result, /* gate */
7573 run_warn_unused_result, /* execute */
7576 0, /* static_pass_number */
7577 TV_NONE, /* tv_id */
7578 PROP_gimple_any, /* properties_required */
7579 0, /* properties_provided */
7580 0, /* properties_destroyed */
7581 0, /* todo_flags_start */
7582 0, /* todo_flags_finish */