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 /* It must be possible to eliminate all phi nodes in B. If ssa form
1358 is not up-to-date, we cannot eliminate any phis; however, if only
1359 some symbols as whole are marked for renaming, this is not a problem,
1360 as phi nodes for those symbols are irrelevant in updating anyway. */
1361 phis = phi_nodes (b);
1362 if (!gimple_seq_empty_p (phis))
1364 gimple_stmt_iterator i;
1366 if (name_mappings_registered_p ())
1369 for (i = gsi_start (phis); !gsi_end_p (i); gsi_next (&i))
1371 gimple phi = gsi_stmt (i);
1373 if (!is_gimple_reg (gimple_phi_result (phi))
1374 && !may_propagate_copy (gimple_phi_result (phi),
1375 gimple_phi_arg_def (phi, 0)))
1380 /* Do not remove user labels. */
1381 for (gsi = gsi_start_bb (b); !gsi_end_p (gsi); gsi_next (&gsi))
1383 stmt = gsi_stmt (gsi);
1384 if (gimple_code (stmt) != GIMPLE_LABEL)
1386 if (!DECL_ARTIFICIAL (gimple_label_label (stmt)))
1390 /* Protect the loop latches. */
1392 && b->loop_father->latch == b)
1398 /* Return true if the var whose chain of uses starts at PTR has no
1401 has_zero_uses_1 (const ssa_use_operand_t *head)
1403 const ssa_use_operand_t *ptr;
1405 for (ptr = head->next; ptr != head; ptr = ptr->next)
1406 if (!is_gimple_debug (USE_STMT (ptr)))
1412 /* Return true if the var whose chain of uses starts at PTR has a
1413 single nondebug use. Set USE_P and STMT to that single nondebug
1414 use, if so, or to NULL otherwise. */
1416 single_imm_use_1 (const ssa_use_operand_t *head,
1417 use_operand_p *use_p, gimple *stmt)
1419 ssa_use_operand_t *ptr, *single_use = 0;
1421 for (ptr = head->next; ptr != head; ptr = ptr->next)
1422 if (!is_gimple_debug (USE_STMT (ptr)))
1433 *use_p = single_use;
1436 *stmt = single_use ? single_use->loc.stmt : NULL;
1438 return !!single_use;
1441 /* Replaces all uses of NAME by VAL. */
1444 replace_uses_by (tree name, tree val)
1446 imm_use_iterator imm_iter;
1451 FOR_EACH_IMM_USE_STMT (stmt, imm_iter, name)
1453 FOR_EACH_IMM_USE_ON_STMT (use, imm_iter)
1455 replace_exp (use, val);
1457 if (gimple_code (stmt) == GIMPLE_PHI)
1459 e = gimple_phi_arg_edge (stmt, PHI_ARG_INDEX_FROM_USE (use));
1460 if (e->flags & EDGE_ABNORMAL)
1462 /* This can only occur for virtual operands, since
1463 for the real ones SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name))
1464 would prevent replacement. */
1465 gcc_assert (!is_gimple_reg (name));
1466 SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val) = 1;
1471 if (gimple_code (stmt) != GIMPLE_PHI)
1475 fold_stmt_inplace (stmt);
1476 if (cfgcleanup_altered_bbs)
1477 bitmap_set_bit (cfgcleanup_altered_bbs, gimple_bb (stmt)->index);
1479 /* FIXME. This should go in update_stmt. */
1480 for (i = 0; i < gimple_num_ops (stmt); i++)
1482 tree op = gimple_op (stmt, i);
1483 /* Operands may be empty here. For example, the labels
1484 of a GIMPLE_COND are nulled out following the creation
1485 of the corresponding CFG edges. */
1486 if (op && TREE_CODE (op) == ADDR_EXPR)
1487 recompute_tree_invariant_for_addr_expr (op);
1490 maybe_clean_or_replace_eh_stmt (stmt, stmt);
1495 gcc_assert (has_zero_uses (name));
1497 /* Also update the trees stored in loop structures. */
1503 FOR_EACH_LOOP (li, loop, 0)
1505 substitute_in_loop_info (loop, name, val);
1510 /* Merge block B into block A. */
1513 gimple_merge_blocks (basic_block a, basic_block b)
1515 gimple_stmt_iterator last, gsi, psi;
1516 gimple_seq phis = phi_nodes (b);
1519 fprintf (dump_file, "Merging blocks %d and %d\n", a->index, b->index);
1521 /* Remove all single-valued PHI nodes from block B of the form
1522 V_i = PHI <V_j> by propagating V_j to all the uses of V_i. */
1523 gsi = gsi_last_bb (a);
1524 for (psi = gsi_start (phis); !gsi_end_p (psi); )
1526 gimple phi = gsi_stmt (psi);
1527 tree def = gimple_phi_result (phi), use = gimple_phi_arg_def (phi, 0);
1529 bool may_replace_uses = !is_gimple_reg (def)
1530 || may_propagate_copy (def, use);
1532 /* In case we maintain loop closed ssa form, do not propagate arguments
1533 of loop exit phi nodes. */
1535 && loops_state_satisfies_p (LOOP_CLOSED_SSA)
1536 && is_gimple_reg (def)
1537 && TREE_CODE (use) == SSA_NAME
1538 && a->loop_father != b->loop_father)
1539 may_replace_uses = false;
1541 if (!may_replace_uses)
1543 gcc_assert (is_gimple_reg (def));
1545 /* Note that just emitting the copies is fine -- there is no problem
1546 with ordering of phi nodes. This is because A is the single
1547 predecessor of B, therefore results of the phi nodes cannot
1548 appear as arguments of the phi nodes. */
1549 copy = gimple_build_assign (def, use);
1550 gsi_insert_after (&gsi, copy, GSI_NEW_STMT);
1551 remove_phi_node (&psi, false);
1555 /* If we deal with a PHI for virtual operands, we can simply
1556 propagate these without fussing with folding or updating
1558 if (!is_gimple_reg (def))
1560 imm_use_iterator iter;
1561 use_operand_p use_p;
1564 FOR_EACH_IMM_USE_STMT (stmt, iter, def)
1565 FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
1566 SET_USE (use_p, use);
1569 replace_uses_by (def, use);
1571 remove_phi_node (&psi, true);
1575 /* Ensure that B follows A. */
1576 move_block_after (b, a);
1578 gcc_assert (single_succ_edge (a)->flags & EDGE_FALLTHRU);
1579 gcc_assert (!last_stmt (a) || !stmt_ends_bb_p (last_stmt (a)));
1581 /* Remove labels from B and set gimple_bb to A for other statements. */
1582 for (gsi = gsi_start_bb (b); !gsi_end_p (gsi);)
1584 if (gimple_code (gsi_stmt (gsi)) == GIMPLE_LABEL)
1586 gimple label = gsi_stmt (gsi);
1588 gsi_remove (&gsi, false);
1590 /* Now that we can thread computed gotos, we might have
1591 a situation where we have a forced label in block B
1592 However, the label at the start of block B might still be
1593 used in other ways (think about the runtime checking for
1594 Fortran assigned gotos). So we can not just delete the
1595 label. Instead we move the label to the start of block A. */
1596 if (FORCED_LABEL (gimple_label_label (label)))
1598 gimple_stmt_iterator dest_gsi = gsi_start_bb (a);
1599 gsi_insert_before (&dest_gsi, label, GSI_NEW_STMT);
1604 gimple_set_bb (gsi_stmt (gsi), a);
1609 /* Merge the sequences. */
1610 last = gsi_last_bb (a);
1611 gsi_insert_seq_after (&last, bb_seq (b), GSI_NEW_STMT);
1612 set_bb_seq (b, NULL);
1614 if (cfgcleanup_altered_bbs)
1615 bitmap_set_bit (cfgcleanup_altered_bbs, a->index);
1619 /* Return the one of two successors of BB that is not reachable by a
1620 complex edge, if there is one. Else, return BB. We use
1621 this in optimizations that use post-dominators for their heuristics,
1622 to catch the cases in C++ where function calls are involved. */
1625 single_noncomplex_succ (basic_block bb)
1628 if (EDGE_COUNT (bb->succs) != 2)
1631 e0 = EDGE_SUCC (bb, 0);
1632 e1 = EDGE_SUCC (bb, 1);
1633 if (e0->flags & EDGE_COMPLEX)
1635 if (e1->flags & EDGE_COMPLEX)
1642 /* Walk the function tree removing unnecessary statements.
1644 * Empty statement nodes are removed
1646 * Unnecessary TRY_FINALLY and TRY_CATCH blocks are removed
1648 * Unnecessary COND_EXPRs are removed
1650 * Some unnecessary BIND_EXPRs are removed
1652 * GOTO_EXPRs immediately preceding destination are removed.
1654 Clearly more work could be done. The trick is doing the analysis
1655 and removal fast enough to be a net improvement in compile times.
1657 Note that when we remove a control structure such as a COND_EXPR
1658 BIND_EXPR, or TRY block, we will need to repeat this optimization pass
1659 to ensure we eliminate all the useless code. */
1668 gimple_stmt_iterator last_goto_gsi;
1672 static void remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *);
1674 /* Given a statement sequence, find the first executable statement with
1675 location information, and warn that it is unreachable. When searching,
1676 descend into containers in execution order. */
1679 remove_useless_stmts_warn_notreached (gimple_seq stmts)
1681 gimple_stmt_iterator gsi;
1683 for (gsi = gsi_start (stmts); !gsi_end_p (gsi); gsi_next (&gsi))
1685 gimple stmt = gsi_stmt (gsi);
1687 if (gimple_no_warning_p (stmt)) return false;
1689 if (gimple_has_location (stmt))
1691 location_t loc = gimple_location (stmt);
1692 if (LOCATION_LINE (loc) > 0)
1694 warning_at (loc, OPT_Wunreachable_code, "will never be executed");
1699 switch (gimple_code (stmt))
1701 /* Unfortunately, we need the CFG now to detect unreachable
1702 branches in a conditional, so conditionals are not handled here. */
1705 if (remove_useless_stmts_warn_notreached (gimple_try_eval (stmt)))
1707 if (remove_useless_stmts_warn_notreached (gimple_try_cleanup (stmt)))
1712 return remove_useless_stmts_warn_notreached (gimple_catch_handler (stmt));
1714 case GIMPLE_EH_FILTER:
1715 return remove_useless_stmts_warn_notreached (gimple_eh_filter_failure (stmt));
1718 return remove_useless_stmts_warn_notreached (gimple_bind_body (stmt));
1728 /* Helper for remove_useless_stmts_1. Handle GIMPLE_COND statements. */
1731 remove_useless_stmts_cond (gimple_stmt_iterator *gsi, struct rus_data *data)
1733 gimple stmt = gsi_stmt (*gsi);
1735 /* The folded result must still be a conditional statement. */
1737 gcc_assert (gsi_stmt (*gsi) == stmt);
1739 data->may_branch = true;
1741 /* Replace trivial conditionals with gotos. */
1742 if (gimple_cond_true_p (stmt))
1744 /* Goto THEN label. */
1745 tree then_label = gimple_cond_true_label (stmt);
1747 gsi_replace (gsi, gimple_build_goto (then_label), false);
1748 data->last_goto_gsi = *gsi;
1749 data->last_was_goto = true;
1750 data->repeat = true;
1752 else if (gimple_cond_false_p (stmt))
1754 /* Goto ELSE label. */
1755 tree else_label = gimple_cond_false_label (stmt);
1757 gsi_replace (gsi, gimple_build_goto (else_label), false);
1758 data->last_goto_gsi = *gsi;
1759 data->last_was_goto = true;
1760 data->repeat = true;
1764 tree then_label = gimple_cond_true_label (stmt);
1765 tree else_label = gimple_cond_false_label (stmt);
1767 if (then_label == else_label)
1769 /* Goto common destination. */
1770 gsi_replace (gsi, gimple_build_goto (then_label), false);
1771 data->last_goto_gsi = *gsi;
1772 data->last_was_goto = true;
1773 data->repeat = true;
1779 data->last_was_goto = false;
1782 /* Helper for remove_useless_stmts_1.
1783 Handle the try-finally case for GIMPLE_TRY statements. */
1786 remove_useless_stmts_tf (gimple_stmt_iterator *gsi, struct rus_data *data)
1788 bool save_may_branch, save_may_throw;
1789 bool this_may_branch, this_may_throw;
1791 gimple_seq eval_seq, cleanup_seq;
1792 gimple_stmt_iterator eval_gsi, cleanup_gsi;
1794 gimple stmt = gsi_stmt (*gsi);
1796 /* Collect may_branch and may_throw information for the body only. */
1797 save_may_branch = data->may_branch;
1798 save_may_throw = data->may_throw;
1799 data->may_branch = false;
1800 data->may_throw = false;
1801 data->last_was_goto = false;
1803 eval_seq = gimple_try_eval (stmt);
1804 eval_gsi = gsi_start (eval_seq);
1805 remove_useless_stmts_1 (&eval_gsi, data);
1807 this_may_branch = data->may_branch;
1808 this_may_throw = data->may_throw;
1809 data->may_branch |= save_may_branch;
1810 data->may_throw |= save_may_throw;
1811 data->last_was_goto = false;
1813 cleanup_seq = gimple_try_cleanup (stmt);
1814 cleanup_gsi = gsi_start (cleanup_seq);
1815 remove_useless_stmts_1 (&cleanup_gsi, data);
1817 /* If the body is empty, then we can emit the FINALLY block without
1818 the enclosing TRY_FINALLY_EXPR. */
1819 if (gimple_seq_empty_p (eval_seq))
1821 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1822 gsi_remove (gsi, false);
1823 data->repeat = true;
1826 /* If the handler is empty, then we can emit the TRY block without
1827 the enclosing TRY_FINALLY_EXPR. */
1828 else if (gimple_seq_empty_p (cleanup_seq))
1830 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1831 gsi_remove (gsi, false);
1832 data->repeat = true;
1835 /* If the body neither throws, nor branches, then we can safely
1836 string the TRY and FINALLY blocks together. */
1837 else if (!this_may_branch && !this_may_throw)
1839 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1840 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1841 gsi_remove (gsi, false);
1842 data->repeat = true;
1848 /* Helper for remove_useless_stmts_1.
1849 Handle the try-catch case for GIMPLE_TRY statements. */
1852 remove_useless_stmts_tc (gimple_stmt_iterator *gsi, struct rus_data *data)
1854 bool save_may_throw, this_may_throw;
1856 gimple_seq eval_seq, cleanup_seq, handler_seq, failure_seq;
1857 gimple_stmt_iterator eval_gsi, cleanup_gsi, handler_gsi, failure_gsi;
1859 gimple stmt = gsi_stmt (*gsi);
1861 /* Collect may_throw information for the body only. */
1862 save_may_throw = data->may_throw;
1863 data->may_throw = false;
1864 data->last_was_goto = false;
1866 eval_seq = gimple_try_eval (stmt);
1867 eval_gsi = gsi_start (eval_seq);
1868 remove_useless_stmts_1 (&eval_gsi, data);
1870 this_may_throw = data->may_throw;
1871 data->may_throw = save_may_throw;
1873 cleanup_seq = gimple_try_cleanup (stmt);
1875 /* If the body cannot throw, then we can drop the entire TRY_CATCH_EXPR. */
1876 if (!this_may_throw)
1878 if (warn_notreached)
1880 remove_useless_stmts_warn_notreached (cleanup_seq);
1882 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1883 gsi_remove (gsi, false);
1884 data->repeat = true;
1888 /* Process the catch clause specially. We may be able to tell that
1889 no exceptions propagate past this point. */
1891 this_may_throw = true;
1892 cleanup_gsi = gsi_start (cleanup_seq);
1893 stmt = gsi_stmt (cleanup_gsi);
1894 data->last_was_goto = false;
1896 switch (gimple_code (stmt))
1899 /* If the first element is a catch, they all must be. */
1900 while (!gsi_end_p (cleanup_gsi))
1902 stmt = gsi_stmt (cleanup_gsi);
1903 /* If we catch all exceptions, then the body does not
1904 propagate exceptions past this point. */
1905 if (gimple_catch_types (stmt) == NULL)
1906 this_may_throw = false;
1907 data->last_was_goto = false;
1908 handler_seq = gimple_catch_handler (stmt);
1909 handler_gsi = gsi_start (handler_seq);
1910 remove_useless_stmts_1 (&handler_gsi, data);
1911 gsi_next (&cleanup_gsi);
1916 case GIMPLE_EH_FILTER:
1917 /* If the first element is an eh_filter, it should stand alone. */
1918 if (gimple_eh_filter_must_not_throw (stmt))
1919 this_may_throw = false;
1920 else if (gimple_eh_filter_types (stmt) == NULL)
1921 this_may_throw = false;
1922 failure_seq = gimple_eh_filter_failure (stmt);
1923 failure_gsi = gsi_start (failure_seq);
1924 remove_useless_stmts_1 (&failure_gsi, data);
1929 /* Otherwise this is a list of cleanup statements. */
1930 remove_useless_stmts_1 (&cleanup_gsi, data);
1932 /* If the cleanup is empty, then we can emit the TRY block without
1933 the enclosing TRY_CATCH_EXPR. */
1934 if (gimple_seq_empty_p (cleanup_seq))
1936 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1937 gsi_remove(gsi, false);
1938 data->repeat = true;
1945 data->may_throw |= this_may_throw;
1948 /* Helper for remove_useless_stmts_1. Handle GIMPLE_BIND statements. */
1951 remove_useless_stmts_bind (gimple_stmt_iterator *gsi, struct rus_data *data ATTRIBUTE_UNUSED)
1954 gimple_seq body_seq, fn_body_seq;
1955 gimple_stmt_iterator body_gsi;
1957 gimple stmt = gsi_stmt (*gsi);
1959 /* First remove anything underneath the BIND_EXPR. */
1961 body_seq = gimple_bind_body (stmt);
1962 body_gsi = gsi_start (body_seq);
1963 remove_useless_stmts_1 (&body_gsi, data);
1965 /* If the GIMPLE_BIND has no variables, then we can pull everything
1966 up one level and remove the GIMPLE_BIND, unless this is the toplevel
1967 GIMPLE_BIND for the current function or an inlined function.
1969 When this situation occurs we will want to apply this
1970 optimization again. */
1971 block = gimple_bind_block (stmt);
1972 fn_body_seq = gimple_body (current_function_decl);
1973 if (gimple_bind_vars (stmt) == NULL_TREE
1974 && (gimple_seq_empty_p (fn_body_seq)
1975 || stmt != gimple_seq_first_stmt (fn_body_seq))
1977 || ! BLOCK_ABSTRACT_ORIGIN (block)
1978 || (TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block))
1981 tree var = NULL_TREE;
1982 /* Even if there are no gimple_bind_vars, there might be other
1983 decls in BLOCK_VARS rendering the GIMPLE_BIND not useless. */
1984 if (block && !BLOCK_NUM_NONLOCALIZED_VARS (block))
1985 for (var = BLOCK_VARS (block); var; var = TREE_CHAIN (var))
1986 if (TREE_CODE (var) == IMPORTED_DECL)
1988 if (var || (block && BLOCK_NUM_NONLOCALIZED_VARS (block)))
1992 gsi_insert_seq_before (gsi, body_seq, GSI_SAME_STMT);
1993 gsi_remove (gsi, false);
1994 data->repeat = true;
2001 /* Helper for remove_useless_stmts_1. Handle GIMPLE_GOTO statements. */
2004 remove_useless_stmts_goto (gimple_stmt_iterator *gsi, struct rus_data *data)
2006 gimple stmt = gsi_stmt (*gsi);
2008 tree dest = gimple_goto_dest (stmt);
2010 data->may_branch = true;
2011 data->last_was_goto = false;
2013 /* Record iterator for last goto expr, so that we can delete it if unnecessary. */
2014 if (TREE_CODE (dest) == LABEL_DECL)
2016 data->last_goto_gsi = *gsi;
2017 data->last_was_goto = true;
2023 /* Helper for remove_useless_stmts_1. Handle GIMPLE_LABEL statements. */
2026 remove_useless_stmts_label (gimple_stmt_iterator *gsi, struct rus_data *data)
2028 gimple stmt = gsi_stmt (*gsi);
2030 tree label = gimple_label_label (stmt);
2032 data->has_label = true;
2034 /* We do want to jump across non-local label receiver code. */
2035 if (DECL_NONLOCAL (label))
2036 data->last_was_goto = false;
2038 else if (data->last_was_goto
2039 && gimple_goto_dest (gsi_stmt (data->last_goto_gsi)) == label)
2041 /* Replace the preceding GIMPLE_GOTO statement with
2042 a GIMPLE_NOP, which will be subsequently removed.
2043 In this way, we avoid invalidating other iterators
2044 active on the statement sequence. */
2045 gsi_replace(&data->last_goto_gsi, gimple_build_nop(), false);
2046 data->last_was_goto = false;
2047 data->repeat = true;
2050 /* ??? Add something here to delete unused labels. */
2056 /* T is CALL_EXPR. Set current_function_calls_* flags. */
2059 notice_special_calls (gimple call)
2061 int flags = gimple_call_flags (call);
2063 if (flags & ECF_MAY_BE_ALLOCA)
2064 cfun->calls_alloca = true;
2065 if (flags & ECF_RETURNS_TWICE)
2066 cfun->calls_setjmp = true;
2070 /* Clear flags set by notice_special_calls. Used by dead code removal
2071 to update the flags. */
2074 clear_special_calls (void)
2076 cfun->calls_alloca = false;
2077 cfun->calls_setjmp = false;
2080 /* Remove useless statements from a statement sequence, and perform
2081 some preliminary simplifications. */
2084 remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *data)
2086 while (!gsi_end_p (*gsi))
2088 gimple stmt = gsi_stmt (*gsi);
2090 switch (gimple_code (stmt))
2093 remove_useless_stmts_cond (gsi, data);
2097 remove_useless_stmts_goto (gsi, data);
2101 remove_useless_stmts_label (gsi, data);
2106 stmt = gsi_stmt (*gsi);
2107 data->last_was_goto = false;
2108 if (stmt_could_throw_p (stmt))
2109 data->may_throw = true;
2115 data->last_was_goto = false;
2121 stmt = gsi_stmt (*gsi);
2122 data->last_was_goto = false;
2123 if (is_gimple_call (stmt))
2124 notice_special_calls (stmt);
2126 /* We used to call update_gimple_call_flags here,
2127 which copied side-effects and nothrows status
2128 from the function decl to the call. In the new
2129 tuplified GIMPLE, the accessors for this information
2130 always consult the function decl, so this copying
2131 is no longer necessary. */
2132 if (stmt_could_throw_p (stmt))
2133 data->may_throw = true;
2139 data->last_was_goto = false;
2140 data->may_branch = true;
2145 remove_useless_stmts_bind (gsi, data);
2149 if (gimple_try_kind (stmt) == GIMPLE_TRY_CATCH)
2150 remove_useless_stmts_tc (gsi, data);
2151 else if (gimple_try_kind (stmt) == GIMPLE_TRY_FINALLY)
2152 remove_useless_stmts_tf (gsi, data);
2162 gsi_remove (gsi, false);
2165 case GIMPLE_OMP_FOR:
2167 gimple_seq pre_body_seq = gimple_omp_for_pre_body (stmt);
2168 gimple_stmt_iterator pre_body_gsi = gsi_start (pre_body_seq);
2170 remove_useless_stmts_1 (&pre_body_gsi, data);
2171 data->last_was_goto = false;
2174 case GIMPLE_OMP_CRITICAL:
2175 case GIMPLE_OMP_CONTINUE:
2176 case GIMPLE_OMP_MASTER:
2177 case GIMPLE_OMP_ORDERED:
2178 case GIMPLE_OMP_SECTION:
2179 case GIMPLE_OMP_SECTIONS:
2180 case GIMPLE_OMP_SINGLE:
2182 gimple_seq body_seq = gimple_omp_body (stmt);
2183 gimple_stmt_iterator body_gsi = gsi_start (body_seq);
2185 remove_useless_stmts_1 (&body_gsi, data);
2186 data->last_was_goto = false;
2191 case GIMPLE_OMP_PARALLEL:
2192 case GIMPLE_OMP_TASK:
2194 /* Make sure the outermost GIMPLE_BIND isn't removed
2196 gimple_seq body_seq = gimple_omp_body (stmt);
2197 gimple bind = gimple_seq_first_stmt (body_seq);
2198 gimple_seq bind_seq = gimple_bind_body (bind);
2199 gimple_stmt_iterator bind_gsi = gsi_start (bind_seq);
2201 remove_useless_stmts_1 (&bind_gsi, data);
2202 data->last_was_goto = false;
2208 data->last_was_goto = false;
2215 /* Walk the function tree, removing useless statements and performing
2216 some preliminary simplifications. */
2219 remove_useless_stmts (void)
2221 struct rus_data data;
2223 clear_special_calls ();
2227 gimple_stmt_iterator gsi;
2229 gsi = gsi_start (gimple_body (current_function_decl));
2230 memset (&data, 0, sizeof (data));
2231 remove_useless_stmts_1 (&gsi, &data);
2233 while (data.repeat);
2235 #ifdef ENABLE_TYPES_CHECKING
2236 verify_types_in_gimple_seq (gimple_body (current_function_decl));
2243 struct gimple_opt_pass pass_remove_useless_stmts =
2247 "useless", /* name */
2249 remove_useless_stmts, /* execute */
2252 0, /* static_pass_number */
2253 TV_NONE, /* tv_id */
2254 PROP_gimple_any, /* properties_required */
2255 0, /* properties_provided */
2256 0, /* properties_destroyed */
2257 0, /* todo_flags_start */
2258 TODO_dump_func /* todo_flags_finish */
2262 /* Remove PHI nodes associated with basic block BB and all edges out of BB. */
2265 remove_phi_nodes_and_edges_for_unreachable_block (basic_block bb)
2267 /* Since this block is no longer reachable, we can just delete all
2268 of its PHI nodes. */
2269 remove_phi_nodes (bb);
2271 /* Remove edges to BB's successors. */
2272 while (EDGE_COUNT (bb->succs) > 0)
2273 remove_edge (EDGE_SUCC (bb, 0));
2277 /* Remove statements of basic block BB. */
2280 remove_bb (basic_block bb)
2282 gimple_stmt_iterator i;
2283 source_location loc = UNKNOWN_LOCATION;
2287 fprintf (dump_file, "Removing basic block %d\n", bb->index);
2288 if (dump_flags & TDF_DETAILS)
2290 dump_bb (bb, dump_file, 0);
2291 fprintf (dump_file, "\n");
2297 struct loop *loop = bb->loop_father;
2299 /* If a loop gets removed, clean up the information associated
2301 if (loop->latch == bb
2302 || loop->header == bb)
2303 free_numbers_of_iterations_estimates_loop (loop);
2306 /* Remove all the instructions in the block. */
2307 if (bb_seq (bb) != NULL)
2309 /* Walk backwards so as to get a chance to substitute all
2310 released DEFs into debug stmts. See
2311 eliminate_unnecessary_stmts() in tree-ssa-dce.c for more
2313 for (i = gsi_last_bb (bb); !gsi_end_p (i);)
2315 gimple stmt = gsi_stmt (i);
2316 if (gimple_code (stmt) == GIMPLE_LABEL
2317 && (FORCED_LABEL (gimple_label_label (stmt))
2318 || DECL_NONLOCAL (gimple_label_label (stmt))))
2321 gimple_stmt_iterator new_gsi;
2323 /* A non-reachable non-local label may still be referenced.
2324 But it no longer needs to carry the extra semantics of
2326 if (DECL_NONLOCAL (gimple_label_label (stmt)))
2328 DECL_NONLOCAL (gimple_label_label (stmt)) = 0;
2329 FORCED_LABEL (gimple_label_label (stmt)) = 1;
2332 new_bb = bb->prev_bb;
2333 new_gsi = gsi_start_bb (new_bb);
2334 gsi_remove (&i, false);
2335 gsi_insert_before (&new_gsi, stmt, GSI_NEW_STMT);
2339 /* Release SSA definitions if we are in SSA. Note that we
2340 may be called when not in SSA. For example,
2341 final_cleanup calls this function via
2342 cleanup_tree_cfg. */
2343 if (gimple_in_ssa_p (cfun))
2344 release_defs (stmt);
2346 gsi_remove (&i, true);
2350 i = gsi_last_bb (bb);
2354 /* Don't warn for removed gotos. Gotos are often removed due to
2355 jump threading, thus resulting in bogus warnings. Not great,
2356 since this way we lose warnings for gotos in the original
2357 program that are indeed unreachable. */
2358 if (gimple_code (stmt) != GIMPLE_GOTO
2359 && gimple_has_location (stmt))
2360 loc = gimple_location (stmt);
2364 /* If requested, give a warning that the first statement in the
2365 block is unreachable. We walk statements backwards in the
2366 loop above, so the last statement we process is the first statement
2368 if (loc > BUILTINS_LOCATION && LOCATION_LINE (loc) > 0)
2369 warning_at (loc, OPT_Wunreachable_code, "will never be executed");
2371 remove_phi_nodes_and_edges_for_unreachable_block (bb);
2372 bb->il.gimple = NULL;
2376 /* Given a basic block BB ending with COND_EXPR or SWITCH_EXPR, and a
2377 predicate VAL, return the edge that will be taken out of the block.
2378 If VAL does not match a unique edge, NULL is returned. */
2381 find_taken_edge (basic_block bb, tree val)
2385 stmt = last_stmt (bb);
2388 gcc_assert (is_ctrl_stmt (stmt));
2393 if (!is_gimple_min_invariant (val))
2396 if (gimple_code (stmt) == GIMPLE_COND)
2397 return find_taken_edge_cond_expr (bb, val);
2399 if (gimple_code (stmt) == GIMPLE_SWITCH)
2400 return find_taken_edge_switch_expr (bb, val);
2402 if (computed_goto_p (stmt))
2404 /* Only optimize if the argument is a label, if the argument is
2405 not a label then we can not construct a proper CFG.
2407 It may be the case that we only need to allow the LABEL_REF to
2408 appear inside an ADDR_EXPR, but we also allow the LABEL_REF to
2409 appear inside a LABEL_EXPR just to be safe. */
2410 if ((TREE_CODE (val) == ADDR_EXPR || TREE_CODE (val) == LABEL_EXPR)
2411 && TREE_CODE (TREE_OPERAND (val, 0)) == LABEL_DECL)
2412 return find_taken_edge_computed_goto (bb, TREE_OPERAND (val, 0));
2419 /* Given a constant value VAL and the entry block BB to a GOTO_EXPR
2420 statement, determine which of the outgoing edges will be taken out of the
2421 block. Return NULL if either edge may be taken. */
2424 find_taken_edge_computed_goto (basic_block bb, tree val)
2429 dest = label_to_block (val);
2432 e = find_edge (bb, dest);
2433 gcc_assert (e != NULL);
2439 /* Given a constant value VAL and the entry block BB to a COND_EXPR
2440 statement, determine which of the two edges will be taken out of the
2441 block. Return NULL if either edge may be taken. */
2444 find_taken_edge_cond_expr (basic_block bb, tree val)
2446 edge true_edge, false_edge;
2448 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
2450 gcc_assert (TREE_CODE (val) == INTEGER_CST);
2451 return (integer_zerop (val) ? false_edge : true_edge);
2454 /* Given an INTEGER_CST VAL and the entry block BB to a SWITCH_EXPR
2455 statement, determine which edge will be taken out of the block. Return
2456 NULL if any edge may be taken. */
2459 find_taken_edge_switch_expr (basic_block bb, tree val)
2461 basic_block dest_bb;
2466 switch_stmt = last_stmt (bb);
2467 taken_case = find_case_label_for_value (switch_stmt, val);
2468 dest_bb = label_to_block (CASE_LABEL (taken_case));
2470 e = find_edge (bb, dest_bb);
2476 /* Return the CASE_LABEL_EXPR that SWITCH_STMT will take for VAL.
2477 We can make optimal use here of the fact that the case labels are
2478 sorted: We can do a binary search for a case matching VAL. */
2481 find_case_label_for_value (gimple switch_stmt, tree val)
2483 size_t low, high, n = gimple_switch_num_labels (switch_stmt);
2484 tree default_case = gimple_switch_default_label (switch_stmt);
2486 for (low = 0, high = n; high - low > 1; )
2488 size_t i = (high + low) / 2;
2489 tree t = gimple_switch_label (switch_stmt, i);
2492 /* Cache the result of comparing CASE_LOW and val. */
2493 cmp = tree_int_cst_compare (CASE_LOW (t), val);
2500 if (CASE_HIGH (t) == NULL)
2502 /* A singe-valued case label. */
2508 /* A case range. We can only handle integer ranges. */
2509 if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
2514 return default_case;
2518 /* Dump a basic block on stderr. */
2521 gimple_debug_bb (basic_block bb)
2523 gimple_dump_bb (bb, stderr, 0, TDF_VOPS|TDF_MEMSYMS);
2527 /* Dump basic block with index N on stderr. */
2530 gimple_debug_bb_n (int n)
2532 gimple_debug_bb (BASIC_BLOCK (n));
2533 return BASIC_BLOCK (n);
2537 /* Dump the CFG on stderr.
2539 FLAGS are the same used by the tree dumping functions
2540 (see TDF_* in tree-pass.h). */
2543 gimple_debug_cfg (int flags)
2545 gimple_dump_cfg (stderr, flags);
2549 /* Dump the program showing basic block boundaries on the given FILE.
2551 FLAGS are the same used by the tree dumping functions (see TDF_* in
2555 gimple_dump_cfg (FILE *file, int flags)
2557 if (flags & TDF_DETAILS)
2559 const char *funcname
2560 = lang_hooks.decl_printable_name (current_function_decl, 2);
2563 fprintf (file, ";; Function %s\n\n", funcname);
2564 fprintf (file, ";; \n%d basic blocks, %d edges, last basic block %d.\n\n",
2565 n_basic_blocks, n_edges, last_basic_block);
2567 brief_dump_cfg (file);
2568 fprintf (file, "\n");
2571 if (flags & TDF_STATS)
2572 dump_cfg_stats (file);
2574 dump_function_to_file (current_function_decl, file, flags | TDF_BLOCKS);
2578 /* Dump CFG statistics on FILE. */
2581 dump_cfg_stats (FILE *file)
2583 static long max_num_merged_labels = 0;
2584 unsigned long size, total = 0;
2587 const char * const fmt_str = "%-30s%-13s%12s\n";
2588 const char * const fmt_str_1 = "%-30s%13d%11lu%c\n";
2589 const char * const fmt_str_2 = "%-30s%13ld%11lu%c\n";
2590 const char * const fmt_str_3 = "%-43s%11lu%c\n";
2591 const char *funcname
2592 = lang_hooks.decl_printable_name (current_function_decl, 2);
2595 fprintf (file, "\nCFG Statistics for %s\n\n", funcname);
2597 fprintf (file, "---------------------------------------------------------\n");
2598 fprintf (file, fmt_str, "", " Number of ", "Memory");
2599 fprintf (file, fmt_str, "", " instances ", "used ");
2600 fprintf (file, "---------------------------------------------------------\n");
2602 size = n_basic_blocks * sizeof (struct basic_block_def);
2604 fprintf (file, fmt_str_1, "Basic blocks", n_basic_blocks,
2605 SCALE (size), LABEL (size));
2609 num_edges += EDGE_COUNT (bb->succs);
2610 size = num_edges * sizeof (struct edge_def);
2612 fprintf (file, fmt_str_2, "Edges", num_edges, SCALE (size), LABEL (size));
2614 fprintf (file, "---------------------------------------------------------\n");
2615 fprintf (file, fmt_str_3, "Total memory used by CFG data", SCALE (total),
2617 fprintf (file, "---------------------------------------------------------\n");
2618 fprintf (file, "\n");
2620 if (cfg_stats.num_merged_labels > max_num_merged_labels)
2621 max_num_merged_labels = cfg_stats.num_merged_labels;
2623 fprintf (file, "Coalesced label blocks: %ld (Max so far: %ld)\n",
2624 cfg_stats.num_merged_labels, max_num_merged_labels);
2626 fprintf (file, "\n");
2630 /* Dump CFG statistics on stderr. Keep extern so that it's always
2631 linked in the final executable. */
2634 debug_cfg_stats (void)
2636 dump_cfg_stats (stderr);
2640 /* Dump the flowgraph to a .vcg FILE. */
2643 gimple_cfg2vcg (FILE *file)
2648 const char *funcname
2649 = lang_hooks.decl_printable_name (current_function_decl, 2);
2651 /* Write the file header. */
2652 fprintf (file, "graph: { title: \"%s\"\n", funcname);
2653 fprintf (file, "node: { title: \"ENTRY\" label: \"ENTRY\" }\n");
2654 fprintf (file, "node: { title: \"EXIT\" label: \"EXIT\" }\n");
2656 /* Write blocks and edges. */
2657 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
2659 fprintf (file, "edge: { sourcename: \"ENTRY\" targetname: \"%d\"",
2662 if (e->flags & EDGE_FAKE)
2663 fprintf (file, " linestyle: dotted priority: 10");
2665 fprintf (file, " linestyle: solid priority: 100");
2667 fprintf (file, " }\n");
2673 enum gimple_code head_code, end_code;
2674 const char *head_name, *end_name;
2677 gimple first = first_stmt (bb);
2678 gimple last = last_stmt (bb);
2682 head_code = gimple_code (first);
2683 head_name = gimple_code_name[head_code];
2684 head_line = get_lineno (first);
2687 head_name = "no-statement";
2691 end_code = gimple_code (last);
2692 end_name = gimple_code_name[end_code];
2693 end_line = get_lineno (last);
2696 end_name = "no-statement";
2698 fprintf (file, "node: { title: \"%d\" label: \"#%d\\n%s (%d)\\n%s (%d)\"}\n",
2699 bb->index, bb->index, head_name, head_line, end_name,
2702 FOR_EACH_EDGE (e, ei, bb->succs)
2704 if (e->dest == EXIT_BLOCK_PTR)
2705 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"EXIT\"", bb->index);
2707 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"%d\"", bb->index, e->dest->index);
2709 if (e->flags & EDGE_FAKE)
2710 fprintf (file, " priority: 10 linestyle: dotted");
2712 fprintf (file, " priority: 100 linestyle: solid");
2714 fprintf (file, " }\n");
2717 if (bb->next_bb != EXIT_BLOCK_PTR)
2721 fputs ("}\n\n", file);
2726 /*---------------------------------------------------------------------------
2727 Miscellaneous helpers
2728 ---------------------------------------------------------------------------*/
2730 /* Return true if T represents a stmt that always transfers control. */
2733 is_ctrl_stmt (gimple t)
2735 return gimple_code (t) == GIMPLE_COND
2736 || gimple_code (t) == GIMPLE_SWITCH
2737 || gimple_code (t) == GIMPLE_GOTO
2738 || gimple_code (t) == GIMPLE_RETURN
2739 || gimple_code (t) == GIMPLE_RESX;
2743 /* Return true if T is a statement that may alter the flow of control
2744 (e.g., a call to a non-returning function). */
2747 is_ctrl_altering_stmt (gimple t)
2751 switch (gimple_code (t))
2755 int flags = gimple_call_flags (t);
2757 /* A non-pure/const call alters flow control if the current
2758 function has nonlocal labels. */
2759 if (!(flags & (ECF_CONST | ECF_PURE)) && cfun->has_nonlocal_label)
2762 /* A call also alters control flow if it does not return. */
2763 if (gimple_call_flags (t) & ECF_NORETURN)
2769 /* OpenMP directives alter control flow. */
2776 /* If a statement can throw, it alters control flow. */
2777 return stmt_can_throw_internal (t);
2781 /* Return true if T is a simple local goto. */
2784 simple_goto_p (gimple t)
2786 return (gimple_code (t) == GIMPLE_GOTO
2787 && TREE_CODE (gimple_goto_dest (t)) == LABEL_DECL);
2791 /* Return true if T can make an abnormal transfer of control flow.
2792 Transfers of control flow associated with EH are excluded. */
2795 stmt_can_make_abnormal_goto (gimple t)
2797 if (computed_goto_p (t))
2799 if (is_gimple_call (t))
2800 return gimple_has_side_effects (t) && cfun->has_nonlocal_label;
2805 /* Return true if STMT should start a new basic block. PREV_STMT is
2806 the statement preceding STMT. It is used when STMT is a label or a
2807 case label. Labels should only start a new basic block if their
2808 previous statement wasn't a label. Otherwise, sequence of labels
2809 would generate unnecessary basic blocks that only contain a single
2813 stmt_starts_bb_p (gimple stmt, gimple prev_stmt)
2818 /* Labels start a new basic block only if the preceding statement
2819 wasn't a label of the same type. This prevents the creation of
2820 consecutive blocks that have nothing but a single label. */
2821 if (gimple_code (stmt) == GIMPLE_LABEL)
2823 /* Nonlocal and computed GOTO targets always start a new block. */
2824 if (DECL_NONLOCAL (gimple_label_label (stmt))
2825 || FORCED_LABEL (gimple_label_label (stmt)))
2828 if (prev_stmt && gimple_code (prev_stmt) == GIMPLE_LABEL)
2830 if (DECL_NONLOCAL (gimple_label_label (prev_stmt)))
2833 cfg_stats.num_merged_labels++;
2844 /* Return true if T should end a basic block. */
2847 stmt_ends_bb_p (gimple t)
2849 return is_ctrl_stmt (t) || is_ctrl_altering_stmt (t);
2852 /* Remove block annotations and other data structures. */
2855 delete_tree_cfg_annotations (void)
2857 label_to_block_map = NULL;
2861 /* Return the first statement in basic block BB. */
2864 first_stmt (basic_block bb)
2866 gimple_stmt_iterator i = gsi_start_bb (bb);
2869 while (!gsi_end_p (i) && is_gimple_debug ((stmt = gsi_stmt (i))))
2877 /* Return the first non-label statement in basic block BB. */
2880 first_non_label_stmt (basic_block bb)
2882 gimple_stmt_iterator i = gsi_start_bb (bb);
2883 while (!gsi_end_p (i) && gimple_code (gsi_stmt (i)) == GIMPLE_LABEL)
2885 return !gsi_end_p (i) ? gsi_stmt (i) : NULL;
2888 /* Return the last statement in basic block BB. */
2891 last_stmt (basic_block bb)
2893 gimple_stmt_iterator i = gsi_last_bb (bb);
2896 while (!gsi_end_p (i) && is_gimple_debug ((stmt = gsi_stmt (i))))
2904 /* Return the last statement of an otherwise empty block. Return NULL
2905 if the block is totally empty, or if it contains more than one
2909 last_and_only_stmt (basic_block bb)
2911 gimple_stmt_iterator i = gsi_last_nondebug_bb (bb);
2917 last = gsi_stmt (i);
2918 gsi_prev_nondebug (&i);
2922 /* Empty statements should no longer appear in the instruction stream.
2923 Everything that might have appeared before should be deleted by
2924 remove_useless_stmts, and the optimizers should just gsi_remove
2925 instead of smashing with build_empty_stmt.
2927 Thus the only thing that should appear here in a block containing
2928 one executable statement is a label. */
2929 prev = gsi_stmt (i);
2930 if (gimple_code (prev) == GIMPLE_LABEL)
2936 /* Reinstall those PHI arguments queued in OLD_EDGE to NEW_EDGE. */
2939 reinstall_phi_args (edge new_edge, edge old_edge)
2941 edge_var_map_vector v;
2944 gimple_stmt_iterator phis;
2946 v = redirect_edge_var_map_vector (old_edge);
2950 for (i = 0, phis = gsi_start_phis (new_edge->dest);
2951 VEC_iterate (edge_var_map, v, i, vm) && !gsi_end_p (phis);
2952 i++, gsi_next (&phis))
2954 gimple phi = gsi_stmt (phis);
2955 tree result = redirect_edge_var_map_result (vm);
2956 tree arg = redirect_edge_var_map_def (vm);
2958 gcc_assert (result == gimple_phi_result (phi));
2960 add_phi_arg (phi, arg, new_edge, redirect_edge_var_map_location (vm));
2963 redirect_edge_var_map_clear (old_edge);
2966 /* Returns the basic block after which the new basic block created
2967 by splitting edge EDGE_IN should be placed. Tries to keep the new block
2968 near its "logical" location. This is of most help to humans looking
2969 at debugging dumps. */
2972 split_edge_bb_loc (edge edge_in)
2974 basic_block dest = edge_in->dest;
2976 if (dest->prev_bb && find_edge (dest->prev_bb, dest))
2977 return edge_in->src;
2979 return dest->prev_bb;
2982 /* Split a (typically critical) edge EDGE_IN. Return the new block.
2983 Abort on abnormal edges. */
2986 gimple_split_edge (edge edge_in)
2988 basic_block new_bb, after_bb, dest;
2991 /* Abnormal edges cannot be split. */
2992 gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
2994 dest = edge_in->dest;
2996 after_bb = split_edge_bb_loc (edge_in);
2998 new_bb = create_empty_bb (after_bb);
2999 new_bb->frequency = EDGE_FREQUENCY (edge_in);
3000 new_bb->count = edge_in->count;
3001 new_edge = make_edge (new_bb, dest, EDGE_FALLTHRU);
3002 new_edge->probability = REG_BR_PROB_BASE;
3003 new_edge->count = edge_in->count;
3005 e = redirect_edge_and_branch (edge_in, new_bb);
3006 gcc_assert (e == edge_in);
3007 reinstall_phi_args (new_edge, e);
3012 /* Callback for walk_tree, check that all elements with address taken are
3013 properly noticed as such. The DATA is an int* that is 1 if TP was seen
3014 inside a PHI node. */
3017 verify_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
3024 /* Check operand N for being valid GIMPLE and give error MSG if not. */
3025 #define CHECK_OP(N, MSG) \
3026 do { if (!is_gimple_val (TREE_OPERAND (t, N))) \
3027 { error (MSG); return TREE_OPERAND (t, N); }} while (0)
3029 switch (TREE_CODE (t))
3032 if (SSA_NAME_IN_FREE_LIST (t))
3034 error ("SSA name in freelist but still referenced");
3040 x = TREE_OPERAND (t, 0);
3041 if (!is_gimple_reg (x) && !is_gimple_min_invariant (x))
3043 error ("Indirect reference's operand is not a register or a constant.");
3049 x = fold (ASSERT_EXPR_COND (t));
3050 if (x == boolean_false_node)
3052 error ("ASSERT_EXPR with an always-false condition");
3058 error ("MODIFY_EXPR not expected while having tuples.");
3064 bool old_side_effects;
3066 bool new_side_effects;
3068 gcc_assert (is_gimple_address (t));
3070 old_constant = TREE_CONSTANT (t);
3071 old_side_effects = TREE_SIDE_EFFECTS (t);
3073 recompute_tree_invariant_for_addr_expr (t);
3074 new_side_effects = TREE_SIDE_EFFECTS (t);
3075 new_constant = TREE_CONSTANT (t);
3077 if (old_constant != new_constant)
3079 error ("constant not recomputed when ADDR_EXPR changed");
3082 if (old_side_effects != new_side_effects)
3084 error ("side effects not recomputed when ADDR_EXPR changed");
3088 /* Skip any references (they will be checked when we recurse down the
3089 tree) and ensure that any variable used as a prefix is marked
3091 for (x = TREE_OPERAND (t, 0);
3092 handled_component_p (x);
3093 x = TREE_OPERAND (x, 0))
3096 if (!(TREE_CODE (x) == VAR_DECL
3097 || TREE_CODE (x) == PARM_DECL
3098 || TREE_CODE (x) == RESULT_DECL))
3100 if (!TREE_ADDRESSABLE (x))
3102 error ("address taken, but ADDRESSABLE bit not set");
3105 if (DECL_GIMPLE_REG_P (x))
3107 error ("DECL_GIMPLE_REG_P set on a variable with address taken");
3115 x = COND_EXPR_COND (t);
3116 if (!INTEGRAL_TYPE_P (TREE_TYPE (x)))
3118 error ("non-integral used in condition");
3121 if (!is_gimple_condexpr (x))
3123 error ("invalid conditional operand");
3128 case NON_LVALUE_EXPR:
3132 case FIX_TRUNC_EXPR:
3137 case TRUTH_NOT_EXPR:
3138 CHECK_OP (0, "invalid operand to unary operator");
3145 case ARRAY_RANGE_REF:
3147 case VIEW_CONVERT_EXPR:
3148 /* We have a nest of references. Verify that each of the operands
3149 that determine where to reference is either a constant or a variable,
3150 verify that the base is valid, and then show we've already checked
3152 while (handled_component_p (t))
3154 if (TREE_CODE (t) == COMPONENT_REF && TREE_OPERAND (t, 2))
3155 CHECK_OP (2, "invalid COMPONENT_REF offset operator");
3156 else if (TREE_CODE (t) == ARRAY_REF
3157 || TREE_CODE (t) == ARRAY_RANGE_REF)
3159 CHECK_OP (1, "invalid array index");
3160 if (TREE_OPERAND (t, 2))
3161 CHECK_OP (2, "invalid array lower bound");
3162 if (TREE_OPERAND (t, 3))
3163 CHECK_OP (3, "invalid array stride");
3165 else if (TREE_CODE (t) == BIT_FIELD_REF)
3167 if (!host_integerp (TREE_OPERAND (t, 1), 1)
3168 || !host_integerp (TREE_OPERAND (t, 2), 1))
3170 error ("invalid position or size operand to BIT_FIELD_REF");
3173 else if (INTEGRAL_TYPE_P (TREE_TYPE (t))
3174 && (TYPE_PRECISION (TREE_TYPE (t))
3175 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
3177 error ("integral result type precision does not match "
3178 "field size of BIT_FIELD_REF");
3181 if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
3182 && (GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (t)))
3183 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
3185 error ("mode precision of non-integral result does not "
3186 "match field size of BIT_FIELD_REF");
3191 t = TREE_OPERAND (t, 0);
3194 if (!is_gimple_min_invariant (t) && !is_gimple_lvalue (t))
3196 error ("invalid reference prefix");
3203 /* PLUS_EXPR and MINUS_EXPR don't work on pointers, they should be done using
3204 POINTER_PLUS_EXPR. */
3205 if (POINTER_TYPE_P (TREE_TYPE (t)))
3207 error ("invalid operand to plus/minus, type is a pointer");
3210 CHECK_OP (0, "invalid operand to binary operator");
3211 CHECK_OP (1, "invalid operand to binary operator");
3214 case POINTER_PLUS_EXPR:
3215 /* Check to make sure the first operand is a pointer or reference type. */
3216 if (!POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 0))))
3218 error ("invalid operand to pointer plus, first operand is not a pointer");
3221 /* Check to make sure the second operand is an integer with type of
3223 if (!useless_type_conversion_p (sizetype,
3224 TREE_TYPE (TREE_OPERAND (t, 1))))
3226 error ("invalid operand to pointer plus, second operand is not an "
3227 "integer with type of sizetype.");
3237 case UNORDERED_EXPR:
3246 case TRUNC_DIV_EXPR:
3248 case FLOOR_DIV_EXPR:
3249 case ROUND_DIV_EXPR:
3250 case TRUNC_MOD_EXPR:
3252 case FLOOR_MOD_EXPR:
3253 case ROUND_MOD_EXPR:
3255 case EXACT_DIV_EXPR:
3265 CHECK_OP (0, "invalid operand to binary operator");
3266 CHECK_OP (1, "invalid operand to binary operator");
3270 if (TREE_CONSTANT (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
3283 /* Verify if EXPR is either a GIMPLE ID or a GIMPLE indirect reference.
3284 Returns true if there is an error, otherwise false. */
3287 verify_types_in_gimple_min_lval (tree expr)
3291 if (is_gimple_id (expr))
3294 if (!INDIRECT_REF_P (expr)
3295 && TREE_CODE (expr) != TARGET_MEM_REF)
3297 error ("invalid expression for min lvalue");
3301 /* TARGET_MEM_REFs are strange beasts. */
3302 if (TREE_CODE (expr) == TARGET_MEM_REF)
3305 op = TREE_OPERAND (expr, 0);
3306 if (!is_gimple_val (op))
3308 error ("invalid operand in indirect reference");
3309 debug_generic_stmt (op);
3312 if (!useless_type_conversion_p (TREE_TYPE (expr),
3313 TREE_TYPE (TREE_TYPE (op))))
3315 error ("type mismatch in indirect reference");
3316 debug_generic_stmt (TREE_TYPE (expr));
3317 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3324 /* Verify if EXPR is a valid GIMPLE reference expression. If
3325 REQUIRE_LVALUE is true verifies it is an lvalue. Returns true
3326 if there is an error, otherwise false. */
3329 verify_types_in_gimple_reference (tree expr, bool require_lvalue)
3331 while (handled_component_p (expr))
3333 tree op = TREE_OPERAND (expr, 0);
3335 if (TREE_CODE (expr) == ARRAY_REF
3336 || TREE_CODE (expr) == ARRAY_RANGE_REF)
3338 if (!is_gimple_val (TREE_OPERAND (expr, 1))
3339 || (TREE_OPERAND (expr, 2)
3340 && !is_gimple_val (TREE_OPERAND (expr, 2)))
3341 || (TREE_OPERAND (expr, 3)
3342 && !is_gimple_val (TREE_OPERAND (expr, 3))))
3344 error ("invalid operands to array reference");
3345 debug_generic_stmt (expr);
3350 /* Verify if the reference array element types are compatible. */
3351 if (TREE_CODE (expr) == ARRAY_REF
3352 && !useless_type_conversion_p (TREE_TYPE (expr),
3353 TREE_TYPE (TREE_TYPE (op))))
3355 error ("type mismatch in array reference");
3356 debug_generic_stmt (TREE_TYPE (expr));
3357 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3360 if (TREE_CODE (expr) == ARRAY_RANGE_REF
3361 && !useless_type_conversion_p (TREE_TYPE (TREE_TYPE (expr)),
3362 TREE_TYPE (TREE_TYPE (op))))
3364 error ("type mismatch in array range reference");
3365 debug_generic_stmt (TREE_TYPE (TREE_TYPE (expr)));
3366 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3370 if ((TREE_CODE (expr) == REALPART_EXPR
3371 || TREE_CODE (expr) == IMAGPART_EXPR)
3372 && !useless_type_conversion_p (TREE_TYPE (expr),
3373 TREE_TYPE (TREE_TYPE (op))))
3375 error ("type mismatch in real/imagpart reference");
3376 debug_generic_stmt (TREE_TYPE (expr));
3377 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3381 if (TREE_CODE (expr) == COMPONENT_REF
3382 && !useless_type_conversion_p (TREE_TYPE (expr),
3383 TREE_TYPE (TREE_OPERAND (expr, 1))))
3385 error ("type mismatch in component reference");
3386 debug_generic_stmt (TREE_TYPE (expr));
3387 debug_generic_stmt (TREE_TYPE (TREE_OPERAND (expr, 1)));
3391 /* For VIEW_CONVERT_EXPRs which are allowed here, too, there
3392 is nothing to verify. Gross mismatches at most invoke
3393 undefined behavior. */
3394 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR
3395 && !handled_component_p (op))
3401 return ((require_lvalue || !is_gimple_min_invariant (expr))
3402 && verify_types_in_gimple_min_lval (expr));
3405 /* Returns true if there is one pointer type in TYPE_POINTER_TO (SRC_OBJ)
3406 list of pointer-to types that is trivially convertible to DEST. */
3409 one_pointer_to_useless_type_conversion_p (tree dest, tree src_obj)
3413 if (!TYPE_POINTER_TO (src_obj))
3416 for (src = TYPE_POINTER_TO (src_obj); src; src = TYPE_NEXT_PTR_TO (src))
3417 if (useless_type_conversion_p (dest, src))
3423 /* Return true if TYPE1 is a fixed-point type and if conversions to and
3424 from TYPE2 can be handled by FIXED_CONVERT_EXPR. */
3427 valid_fixed_convert_types_p (tree type1, tree type2)
3429 return (FIXED_POINT_TYPE_P (type1)
3430 && (INTEGRAL_TYPE_P (type2)
3431 || SCALAR_FLOAT_TYPE_P (type2)
3432 || FIXED_POINT_TYPE_P (type2)));
3435 /* Verify the contents of a GIMPLE_CALL STMT. Returns true when there
3436 is a problem, otherwise false. */
3439 verify_gimple_call (gimple stmt)
3441 tree fn = gimple_call_fn (stmt);
3444 if (!POINTER_TYPE_P (TREE_TYPE (fn))
3445 || (TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != FUNCTION_TYPE
3446 && TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != METHOD_TYPE))
3448 error ("non-function in gimple call");
3452 if (gimple_call_lhs (stmt)
3453 && !is_gimple_lvalue (gimple_call_lhs (stmt)))
3455 error ("invalid LHS in gimple call");
3459 fntype = TREE_TYPE (TREE_TYPE (fn));
3460 if (gimple_call_lhs (stmt)
3461 && !useless_type_conversion_p (TREE_TYPE (gimple_call_lhs (stmt)),
3463 /* ??? At least C++ misses conversions at assignments from
3464 void * call results.
3465 ??? Java is completely off. Especially with functions
3466 returning java.lang.Object.
3467 For now simply allow arbitrary pointer type conversions. */
3468 && !(POINTER_TYPE_P (TREE_TYPE (gimple_call_lhs (stmt)))
3469 && POINTER_TYPE_P (TREE_TYPE (fntype))))
3471 error ("invalid conversion in gimple call");
3472 debug_generic_stmt (TREE_TYPE (gimple_call_lhs (stmt)));
3473 debug_generic_stmt (TREE_TYPE (fntype));
3477 /* ??? The C frontend passes unpromoted arguments in case it
3478 didn't see a function declaration before the call. So for now
3479 leave the call arguments unverified. Once we gimplify
3480 unit-at-a-time we have a chance to fix this. */
3485 /* Verifies the gimple comparison with the result type TYPE and
3486 the operands OP0 and OP1. */
3489 verify_gimple_comparison (tree type, tree op0, tree op1)
3491 tree op0_type = TREE_TYPE (op0);
3492 tree op1_type = TREE_TYPE (op1);
3494 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3496 error ("invalid operands in gimple comparison");
3500 /* For comparisons we do not have the operations type as the
3501 effective type the comparison is carried out in. Instead
3502 we require that either the first operand is trivially
3503 convertible into the second, or the other way around.
3504 The resulting type of a comparison may be any integral type.
3505 Because we special-case pointers to void we allow
3506 comparisons of pointers with the same mode as well. */
3507 if ((!useless_type_conversion_p (op0_type, op1_type)
3508 && !useless_type_conversion_p (op1_type, op0_type)
3509 && (!POINTER_TYPE_P (op0_type)
3510 || !POINTER_TYPE_P (op1_type)
3511 || TYPE_MODE (op0_type) != TYPE_MODE (op1_type)))
3512 || !INTEGRAL_TYPE_P (type))
3514 error ("type mismatch in comparison expression");
3515 debug_generic_expr (type);
3516 debug_generic_expr (op0_type);
3517 debug_generic_expr (op1_type);
3524 /* Verify a gimple assignment statement STMT with an unary rhs.
3525 Returns true if anything is wrong. */
3528 verify_gimple_assign_unary (gimple stmt)
3530 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3531 tree lhs = gimple_assign_lhs (stmt);
3532 tree lhs_type = TREE_TYPE (lhs);
3533 tree rhs1 = gimple_assign_rhs1 (stmt);
3534 tree rhs1_type = TREE_TYPE (rhs1);
3536 if (!is_gimple_reg (lhs)
3538 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3540 error ("non-register as LHS of unary operation");
3544 if (!is_gimple_val (rhs1))
3546 error ("invalid operand in unary operation");
3550 /* First handle conversions. */
3555 /* Allow conversions between integral types and pointers only if
3556 there is no sign or zero extension involved.
3557 For targets were the precision of sizetype doesn't match that
3558 of pointers we need to allow arbitrary conversions from and
3560 if ((POINTER_TYPE_P (lhs_type)
3561 && INTEGRAL_TYPE_P (rhs1_type)
3562 && (TYPE_PRECISION (lhs_type) >= TYPE_PRECISION (rhs1_type)
3563 || rhs1_type == sizetype))
3564 || (POINTER_TYPE_P (rhs1_type)
3565 && INTEGRAL_TYPE_P (lhs_type)
3566 && (TYPE_PRECISION (rhs1_type) >= TYPE_PRECISION (lhs_type)
3567 || lhs_type == sizetype)))
3570 /* Allow conversion from integer to offset type and vice versa. */
3571 if ((TREE_CODE (lhs_type) == OFFSET_TYPE
3572 && TREE_CODE (rhs1_type) == INTEGER_TYPE)
3573 || (TREE_CODE (lhs_type) == INTEGER_TYPE
3574 && TREE_CODE (rhs1_type) == OFFSET_TYPE))
3577 /* Otherwise assert we are converting between types of the
3579 if (INTEGRAL_TYPE_P (lhs_type) != INTEGRAL_TYPE_P (rhs1_type))
3581 error ("invalid types in nop conversion");
3582 debug_generic_expr (lhs_type);
3583 debug_generic_expr (rhs1_type);
3590 case FIXED_CONVERT_EXPR:
3592 if (!valid_fixed_convert_types_p (lhs_type, rhs1_type)
3593 && !valid_fixed_convert_types_p (rhs1_type, lhs_type))
3595 error ("invalid types in fixed-point conversion");
3596 debug_generic_expr (lhs_type);
3597 debug_generic_expr (rhs1_type);
3606 if (!INTEGRAL_TYPE_P (rhs1_type) || !SCALAR_FLOAT_TYPE_P (lhs_type))
3608 error ("invalid types in conversion to floating point");
3609 debug_generic_expr (lhs_type);
3610 debug_generic_expr (rhs1_type);
3617 case FIX_TRUNC_EXPR:
3619 if (!INTEGRAL_TYPE_P (lhs_type) || !SCALAR_FLOAT_TYPE_P (rhs1_type))
3621 error ("invalid types in conversion to integer");
3622 debug_generic_expr (lhs_type);
3623 debug_generic_expr (rhs1_type);
3630 case VEC_UNPACK_HI_EXPR:
3631 case VEC_UNPACK_LO_EXPR:
3632 case REDUC_MAX_EXPR:
3633 case REDUC_MIN_EXPR:
3634 case REDUC_PLUS_EXPR:
3635 case VEC_UNPACK_FLOAT_HI_EXPR:
3636 case VEC_UNPACK_FLOAT_LO_EXPR:
3640 case TRUTH_NOT_EXPR:
3645 case NON_LVALUE_EXPR:
3653 /* For the remaining codes assert there is no conversion involved. */
3654 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3656 error ("non-trivial conversion in unary operation");
3657 debug_generic_expr (lhs_type);
3658 debug_generic_expr (rhs1_type);
3665 /* Verify a gimple assignment statement STMT with a binary rhs.
3666 Returns true if anything is wrong. */
3669 verify_gimple_assign_binary (gimple stmt)
3671 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3672 tree lhs = gimple_assign_lhs (stmt);
3673 tree lhs_type = TREE_TYPE (lhs);
3674 tree rhs1 = gimple_assign_rhs1 (stmt);
3675 tree rhs1_type = TREE_TYPE (rhs1);
3676 tree rhs2 = gimple_assign_rhs2 (stmt);
3677 tree rhs2_type = TREE_TYPE (rhs2);
3679 if (!is_gimple_reg (lhs)
3681 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3683 error ("non-register as LHS of binary operation");
3687 if (!is_gimple_val (rhs1)
3688 || !is_gimple_val (rhs2))
3690 error ("invalid operands in binary operation");
3694 /* First handle operations that involve different types. */
3699 if (TREE_CODE (lhs_type) != COMPLEX_TYPE
3700 || !(INTEGRAL_TYPE_P (rhs1_type)
3701 || SCALAR_FLOAT_TYPE_P (rhs1_type))
3702 || !(INTEGRAL_TYPE_P (rhs2_type)
3703 || SCALAR_FLOAT_TYPE_P (rhs2_type)))
3705 error ("type mismatch in complex expression");
3706 debug_generic_expr (lhs_type);
3707 debug_generic_expr (rhs1_type);
3708 debug_generic_expr (rhs2_type);
3720 /* Shifts and rotates are ok on integral types, fixed point
3721 types and integer vector types. */
3722 if ((!INTEGRAL_TYPE_P (rhs1_type)
3723 && !FIXED_POINT_TYPE_P (rhs1_type)
3724 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3725 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE))
3726 || (!INTEGRAL_TYPE_P (rhs2_type)
3727 /* Vector shifts of vectors are also ok. */
3728 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3729 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE
3730 && TREE_CODE (rhs2_type) == VECTOR_TYPE
3731 && TREE_CODE (TREE_TYPE (rhs2_type)) == INTEGER_TYPE))
3732 || !useless_type_conversion_p (lhs_type, rhs1_type))
3734 error ("type mismatch in shift expression");
3735 debug_generic_expr (lhs_type);
3736 debug_generic_expr (rhs1_type);
3737 debug_generic_expr (rhs2_type);
3744 case VEC_LSHIFT_EXPR:
3745 case VEC_RSHIFT_EXPR:
3747 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3748 || !(INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))
3749 || FIXED_POINT_TYPE_P (TREE_TYPE (rhs1_type))
3750 || SCALAR_FLOAT_TYPE_P (TREE_TYPE (rhs1_type)))
3751 || (!INTEGRAL_TYPE_P (rhs2_type)
3752 && (TREE_CODE (rhs2_type) != VECTOR_TYPE
3753 || !INTEGRAL_TYPE_P (TREE_TYPE (rhs2_type))))
3754 || !useless_type_conversion_p (lhs_type, rhs1_type))
3756 error ("type mismatch in vector shift expression");
3757 debug_generic_expr (lhs_type);
3758 debug_generic_expr (rhs1_type);
3759 debug_generic_expr (rhs2_type);
3762 /* For shifting a vector of floating point components we
3763 only allow shifting by a constant multiple of the element size. */
3764 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (rhs1_type))
3765 && (TREE_CODE (rhs2) != INTEGER_CST
3766 || !div_if_zero_remainder (EXACT_DIV_EXPR, rhs2,
3767 TYPE_SIZE (TREE_TYPE (rhs1_type)))))
3769 error ("non-element sized vector shift of floating point vector");
3778 /* We use regular PLUS_EXPR for vectors.
3779 ??? This just makes the checker happy and may not be what is
3781 if (TREE_CODE (lhs_type) == VECTOR_TYPE
3782 && POINTER_TYPE_P (TREE_TYPE (lhs_type)))
3784 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3785 || TREE_CODE (rhs2_type) != VECTOR_TYPE)
3787 error ("invalid non-vector operands to vector valued plus");
3790 lhs_type = TREE_TYPE (lhs_type);
3791 rhs1_type = TREE_TYPE (rhs1_type);
3792 rhs2_type = TREE_TYPE (rhs2_type);
3793 /* PLUS_EXPR is commutative, so we might end up canonicalizing
3794 the pointer to 2nd place. */
3795 if (POINTER_TYPE_P (rhs2_type))
3797 tree tem = rhs1_type;
3798 rhs1_type = rhs2_type;
3801 goto do_pointer_plus_expr_check;
3807 if (POINTER_TYPE_P (lhs_type)
3808 || POINTER_TYPE_P (rhs1_type)
3809 || POINTER_TYPE_P (rhs2_type))
3811 error ("invalid (pointer) operands to plus/minus");
3815 /* Continue with generic binary expression handling. */
3819 case POINTER_PLUS_EXPR:
3821 do_pointer_plus_expr_check:
3822 if (!POINTER_TYPE_P (rhs1_type)
3823 || !useless_type_conversion_p (lhs_type, rhs1_type)
3824 || !useless_type_conversion_p (sizetype, rhs2_type))
3826 error ("type mismatch in pointer plus expression");
3827 debug_generic_stmt (lhs_type);
3828 debug_generic_stmt (rhs1_type);
3829 debug_generic_stmt (rhs2_type);
3836 case TRUTH_ANDIF_EXPR:
3837 case TRUTH_ORIF_EXPR:
3840 case TRUTH_AND_EXPR:
3842 case TRUTH_XOR_EXPR:
3844 /* We allow any kind of integral typed argument and result. */
3845 if (!INTEGRAL_TYPE_P (rhs1_type)
3846 || !INTEGRAL_TYPE_P (rhs2_type)
3847 || !INTEGRAL_TYPE_P (lhs_type))
3849 error ("type mismatch in binary truth expression");
3850 debug_generic_expr (lhs_type);
3851 debug_generic_expr (rhs1_type);
3852 debug_generic_expr (rhs2_type);
3865 case UNORDERED_EXPR:
3873 /* Comparisons are also binary, but the result type is not
3874 connected to the operand types. */
3875 return verify_gimple_comparison (lhs_type, rhs1, rhs2);
3877 case WIDEN_SUM_EXPR:
3878 case WIDEN_MULT_EXPR:
3879 case VEC_WIDEN_MULT_HI_EXPR:
3880 case VEC_WIDEN_MULT_LO_EXPR:
3881 case VEC_PACK_TRUNC_EXPR:
3882 case VEC_PACK_SAT_EXPR:
3883 case VEC_PACK_FIX_TRUNC_EXPR:
3884 case VEC_EXTRACT_EVEN_EXPR:
3885 case VEC_EXTRACT_ODD_EXPR:
3886 case VEC_INTERLEAVE_HIGH_EXPR:
3887 case VEC_INTERLEAVE_LOW_EXPR:
3892 case TRUNC_DIV_EXPR:
3894 case FLOOR_DIV_EXPR:
3895 case ROUND_DIV_EXPR:
3896 case TRUNC_MOD_EXPR:
3898 case FLOOR_MOD_EXPR:
3899 case ROUND_MOD_EXPR:
3901 case EXACT_DIV_EXPR:
3907 /* Continue with generic binary expression handling. */
3914 if (!useless_type_conversion_p (lhs_type, rhs1_type)
3915 || !useless_type_conversion_p (lhs_type, rhs2_type))
3917 error ("type mismatch in binary expression");
3918 debug_generic_stmt (lhs_type);
3919 debug_generic_stmt (rhs1_type);
3920 debug_generic_stmt (rhs2_type);
3927 /* Verify a gimple assignment statement STMT with a single rhs.
3928 Returns true if anything is wrong. */
3931 verify_gimple_assign_single (gimple stmt)
3933 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3934 tree lhs = gimple_assign_lhs (stmt);
3935 tree lhs_type = TREE_TYPE (lhs);
3936 tree rhs1 = gimple_assign_rhs1 (stmt);
3937 tree rhs1_type = TREE_TYPE (rhs1);
3940 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3942 error ("non-trivial conversion at assignment");
3943 debug_generic_expr (lhs_type);
3944 debug_generic_expr (rhs1_type);
3948 if (handled_component_p (lhs))
3949 res |= verify_types_in_gimple_reference (lhs, true);
3951 /* Special codes we cannot handle via their class. */
3956 tree op = TREE_OPERAND (rhs1, 0);
3957 if (!is_gimple_addressable (op))
3959 error ("invalid operand in unary expression");
3963 if (!types_compatible_p (TREE_TYPE (op), TREE_TYPE (TREE_TYPE (rhs1)))
3964 && !one_pointer_to_useless_type_conversion_p (TREE_TYPE (rhs1),
3967 error ("type mismatch in address expression");
3968 debug_generic_stmt (TREE_TYPE (rhs1));
3969 debug_generic_stmt (TREE_TYPE (op));
3973 return verify_types_in_gimple_reference (op, true);
3980 case ALIGN_INDIRECT_REF:
3981 case MISALIGNED_INDIRECT_REF:
3983 case ARRAY_RANGE_REF:
3984 case VIEW_CONVERT_EXPR:
3987 case TARGET_MEM_REF:
3988 if (!is_gimple_reg (lhs)
3989 && is_gimple_reg_type (TREE_TYPE (lhs)))
3991 error ("invalid rhs for gimple memory store");
3992 debug_generic_stmt (lhs);
3993 debug_generic_stmt (rhs1);
3996 return res || verify_types_in_gimple_reference (rhs1, false);
4008 /* tcc_declaration */
4013 if (!is_gimple_reg (lhs)
4014 && !is_gimple_reg (rhs1)
4015 && is_gimple_reg_type (TREE_TYPE (lhs)))
4017 error ("invalid rhs for gimple memory store");
4018 debug_generic_stmt (lhs);
4019 debug_generic_stmt (rhs1);
4028 case WITH_SIZE_EXPR:
4031 case POLYNOMIAL_CHREC:
4034 case REALIGN_LOAD_EXPR:
4044 /* Verify the contents of a GIMPLE_ASSIGN STMT. Returns true when there
4045 is a problem, otherwise false. */
4048 verify_gimple_assign (gimple stmt)
4050 switch (gimple_assign_rhs_class (stmt))
4052 case GIMPLE_SINGLE_RHS:
4053 return verify_gimple_assign_single (stmt);
4055 case GIMPLE_UNARY_RHS:
4056 return verify_gimple_assign_unary (stmt);
4058 case GIMPLE_BINARY_RHS:
4059 return verify_gimple_assign_binary (stmt);
4066 /* Verify the contents of a GIMPLE_RETURN STMT. Returns true when there
4067 is a problem, otherwise false. */
4070 verify_gimple_return (gimple stmt)
4072 tree op = gimple_return_retval (stmt);
4073 tree restype = TREE_TYPE (TREE_TYPE (cfun->decl));
4075 /* We cannot test for present return values as we do not fix up missing
4076 return values from the original source. */
4080 if (!is_gimple_val (op)
4081 && TREE_CODE (op) != RESULT_DECL)
4083 error ("invalid operand in return statement");
4084 debug_generic_stmt (op);
4088 if (!useless_type_conversion_p (restype, TREE_TYPE (op))
4089 /* ??? With C++ we can have the situation that the result
4090 decl is a reference type while the return type is an aggregate. */
4091 && !(TREE_CODE (op) == RESULT_DECL
4092 && TREE_CODE (TREE_TYPE (op)) == REFERENCE_TYPE
4093 && useless_type_conversion_p (restype, TREE_TYPE (TREE_TYPE (op)))))
4095 error ("invalid conversion in return statement");
4096 debug_generic_stmt (restype);
4097 debug_generic_stmt (TREE_TYPE (op));
4105 /* Verify the contents of a GIMPLE_GOTO STMT. Returns true when there
4106 is a problem, otherwise false. */
4109 verify_gimple_goto (gimple stmt)
4111 tree dest = gimple_goto_dest (stmt);
4113 /* ??? We have two canonical forms of direct goto destinations, a
4114 bare LABEL_DECL and an ADDR_EXPR of a LABEL_DECL. */
4115 if (TREE_CODE (dest) != LABEL_DECL
4116 && (!is_gimple_val (dest)
4117 || !POINTER_TYPE_P (TREE_TYPE (dest))))
4119 error ("goto destination is neither a label nor a pointer");
4126 /* Verify the contents of a GIMPLE_SWITCH STMT. Returns true when there
4127 is a problem, otherwise false. */
4130 verify_gimple_switch (gimple stmt)
4132 if (!is_gimple_val (gimple_switch_index (stmt)))
4134 error ("invalid operand to switch statement");
4135 debug_generic_stmt (gimple_switch_index (stmt));
4143 /* Verify the contents of a GIMPLE_PHI. Returns true if there is a problem,
4144 and false otherwise. */
4147 verify_gimple_phi (gimple stmt)
4149 tree type = TREE_TYPE (gimple_phi_result (stmt));
4152 if (TREE_CODE (gimple_phi_result (stmt)) != SSA_NAME)
4154 error ("Invalid PHI result");
4158 for (i = 0; i < gimple_phi_num_args (stmt); i++)
4160 tree arg = gimple_phi_arg_def (stmt, i);
4161 if ((is_gimple_reg (gimple_phi_result (stmt))
4162 && !is_gimple_val (arg))
4163 || (!is_gimple_reg (gimple_phi_result (stmt))
4164 && !is_gimple_addressable (arg)))
4166 error ("Invalid PHI argument");
4167 debug_generic_stmt (arg);
4170 if (!useless_type_conversion_p (type, TREE_TYPE (arg)))
4172 error ("Incompatible types in PHI argument %u", i);
4173 debug_generic_stmt (type);
4174 debug_generic_stmt (TREE_TYPE (arg));
4183 /* Verify a gimple debug statement STMT.
4184 Returns true if anything is wrong. */
4187 verify_gimple_debug (gimple stmt ATTRIBUTE_UNUSED)
4189 /* There isn't much that could be wrong in a gimple debug stmt. A
4190 gimple debug bind stmt, for example, maps a tree, that's usually
4191 a VAR_DECL or a PARM_DECL, but that could also be some scalarized
4192 component or member of an aggregate type, to another tree, that
4193 can be an arbitrary expression. These stmts expand into debug
4194 insns, and are converted to debug notes by var-tracking.c. */
4199 /* Verify the GIMPLE statement STMT. Returns true if there is an
4200 error, otherwise false. */
4203 verify_types_in_gimple_stmt (gimple stmt)
4205 switch (gimple_code (stmt))
4208 return verify_gimple_assign (stmt);
4211 return TREE_CODE (gimple_label_label (stmt)) != LABEL_DECL;
4214 return verify_gimple_call (stmt);
4217 return verify_gimple_comparison (boolean_type_node,
4218 gimple_cond_lhs (stmt),
4219 gimple_cond_rhs (stmt));
4222 return verify_gimple_goto (stmt);
4225 return verify_gimple_switch (stmt);
4228 return verify_gimple_return (stmt);
4234 return verify_gimple_phi (stmt);
4236 /* Tuples that do not have tree operands. */
4239 case GIMPLE_PREDICT:
4243 /* OpenMP directives are validated by the FE and never operated
4244 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4245 non-gimple expressions when the main index variable has had
4246 its address taken. This does not affect the loop itself
4247 because the header of an GIMPLE_OMP_FOR is merely used to determine
4248 how to setup the parallel iteration. */
4252 return verify_gimple_debug (stmt);
4259 /* Verify the GIMPLE statements inside the sequence STMTS. */
4262 verify_types_in_gimple_seq_2 (gimple_seq stmts)
4264 gimple_stmt_iterator ittr;
4267 for (ittr = gsi_start (stmts); !gsi_end_p (ittr); gsi_next (&ittr))
4269 gimple stmt = gsi_stmt (ittr);
4271 switch (gimple_code (stmt))
4274 err |= verify_types_in_gimple_seq_2 (gimple_bind_body (stmt));
4278 err |= verify_types_in_gimple_seq_2 (gimple_try_eval (stmt));
4279 err |= verify_types_in_gimple_seq_2 (gimple_try_cleanup (stmt));
4282 case GIMPLE_EH_FILTER:
4283 err |= verify_types_in_gimple_seq_2 (gimple_eh_filter_failure (stmt));
4287 err |= verify_types_in_gimple_seq_2 (gimple_catch_handler (stmt));
4292 bool err2 = verify_types_in_gimple_stmt (stmt);
4294 debug_gimple_stmt (stmt);
4304 /* Verify the GIMPLE statements inside the statement list STMTS. */
4307 verify_types_in_gimple_seq (gimple_seq stmts)
4309 if (verify_types_in_gimple_seq_2 (stmts))
4310 internal_error ("verify_gimple failed");
4314 /* Verify STMT, return true if STMT is not in GIMPLE form.
4315 TODO: Implement type checking. */
4318 verify_stmt (gimple_stmt_iterator *gsi)
4321 struct walk_stmt_info wi;
4322 bool last_in_block = gsi_one_before_end_p (*gsi);
4323 gimple stmt = gsi_stmt (*gsi);
4325 if (is_gimple_omp (stmt))
4327 /* OpenMP directives are validated by the FE and never operated
4328 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4329 non-gimple expressions when the main index variable has had
4330 its address taken. This does not affect the loop itself
4331 because the header of an GIMPLE_OMP_FOR is merely used to determine
4332 how to setup the parallel iteration. */
4336 /* FIXME. The C frontend passes unpromoted arguments in case it
4337 didn't see a function declaration before the call. */
4338 if (is_gimple_call (stmt))
4342 if (!is_gimple_call_addr (gimple_call_fn (stmt)))
4344 error ("invalid function in call statement");
4348 decl = gimple_call_fndecl (stmt);
4350 && TREE_CODE (decl) == FUNCTION_DECL
4351 && DECL_LOOPING_CONST_OR_PURE_P (decl)
4352 && (!DECL_PURE_P (decl))
4353 && (!TREE_READONLY (decl)))
4355 error ("invalid pure const state for function");
4360 if (is_gimple_debug (stmt))
4363 memset (&wi, 0, sizeof (wi));
4364 addr = walk_gimple_op (gsi_stmt (*gsi), verify_expr, &wi);
4367 debug_generic_expr (addr);
4368 inform (gimple_location (gsi_stmt (*gsi)), "in statement");
4369 debug_gimple_stmt (stmt);
4373 /* If the statement is marked as part of an EH region, then it is
4374 expected that the statement could throw. Verify that when we
4375 have optimizations that simplify statements such that we prove
4376 that they cannot throw, that we update other data structures
4378 if (lookup_stmt_eh_region (stmt) >= 0)
4380 /* During IPA passes, ipa-pure-const sets nothrow flags on calls
4381 and they are updated on statements only after fixup_cfg
4382 is executed at beggining of expansion stage. */
4383 if (!stmt_could_throw_p (stmt) && cgraph_state != CGRAPH_STATE_IPA_SSA)
4385 error ("statement marked for throw, but doesn%'t");
4388 if (!last_in_block && stmt_can_throw_internal (stmt))
4390 error ("statement marked for throw in middle of block");
4398 debug_gimple_stmt (stmt);
4403 /* Return true when the T can be shared. */
4406 tree_node_can_be_shared (tree t)
4408 if (IS_TYPE_OR_DECL_P (t)
4409 || is_gimple_min_invariant (t)
4410 || TREE_CODE (t) == SSA_NAME
4411 || t == error_mark_node
4412 || TREE_CODE (t) == IDENTIFIER_NODE)
4415 if (TREE_CODE (t) == CASE_LABEL_EXPR)
4418 while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4419 && is_gimple_min_invariant (TREE_OPERAND (t, 1)))
4420 || TREE_CODE (t) == COMPONENT_REF
4421 || TREE_CODE (t) == REALPART_EXPR
4422 || TREE_CODE (t) == IMAGPART_EXPR)
4423 t = TREE_OPERAND (t, 0);
4432 /* Called via walk_gimple_stmt. Verify tree sharing. */
4435 verify_node_sharing (tree *tp, int *walk_subtrees, void *data)
4437 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
4438 struct pointer_set_t *visited = (struct pointer_set_t *) wi->info;
4440 if (tree_node_can_be_shared (*tp))
4442 *walk_subtrees = false;
4446 if (pointer_set_insert (visited, *tp))
4453 static bool eh_error_found;
4455 verify_eh_throw_stmt_node (void **slot, void *data)
4457 struct throw_stmt_node *node = (struct throw_stmt_node *)*slot;
4458 struct pointer_set_t *visited = (struct pointer_set_t *) data;
4460 if (!pointer_set_contains (visited, node->stmt))
4462 error ("Dead STMT in EH table");
4463 debug_gimple_stmt (node->stmt);
4464 eh_error_found = true;
4470 /* Verify the GIMPLE statements in every basic block. */
4476 gimple_stmt_iterator gsi;
4478 struct pointer_set_t *visited, *visited_stmts;
4480 struct walk_stmt_info wi;
4482 timevar_push (TV_TREE_STMT_VERIFY);
4483 visited = pointer_set_create ();
4484 visited_stmts = pointer_set_create ();
4486 memset (&wi, 0, sizeof (wi));
4487 wi.info = (void *) visited;
4494 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4496 phi = gsi_stmt (gsi);
4497 pointer_set_insert (visited_stmts, phi);
4498 if (gimple_bb (phi) != bb)
4500 error ("gimple_bb (phi) is set to a wrong basic block");
4504 for (i = 0; i < gimple_phi_num_args (phi); i++)
4506 tree t = gimple_phi_arg_def (phi, i);
4511 error ("missing PHI def");
4512 debug_gimple_stmt (phi);
4516 /* Addressable variables do have SSA_NAMEs but they
4517 are not considered gimple values. */
4518 else if (TREE_CODE (t) != SSA_NAME
4519 && TREE_CODE (t) != FUNCTION_DECL
4520 && !is_gimple_min_invariant (t))
4522 error ("PHI argument is not a GIMPLE value");
4523 debug_gimple_stmt (phi);
4524 debug_generic_expr (t);
4528 addr = walk_tree (&t, verify_node_sharing, visited, NULL);
4531 error ("incorrect sharing of tree nodes");
4532 debug_gimple_stmt (phi);
4533 debug_generic_expr (addr);
4538 #ifdef ENABLE_TYPES_CHECKING
4539 if (verify_gimple_phi (phi))
4541 debug_gimple_stmt (phi);
4547 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); )
4549 gimple stmt = gsi_stmt (gsi);
4551 if (gimple_code (stmt) == GIMPLE_WITH_CLEANUP_EXPR
4552 || gimple_code (stmt) == GIMPLE_BIND)
4554 error ("invalid GIMPLE statement");
4555 debug_gimple_stmt (stmt);
4559 pointer_set_insert (visited_stmts, stmt);
4561 if (gimple_bb (stmt) != bb)
4563 error ("gimple_bb (stmt) is set to a wrong basic block");
4564 debug_gimple_stmt (stmt);
4568 if (gimple_code (stmt) == GIMPLE_LABEL)
4570 tree decl = gimple_label_label (stmt);
4571 int uid = LABEL_DECL_UID (decl);
4574 || VEC_index (basic_block, label_to_block_map, uid) != bb)
4576 error ("incorrect entry in label_to_block_map.\n");
4581 err |= verify_stmt (&gsi);
4583 #ifdef ENABLE_TYPES_CHECKING
4584 if (verify_types_in_gimple_stmt (gsi_stmt (gsi)))
4586 debug_gimple_stmt (stmt);
4590 addr = walk_gimple_op (gsi_stmt (gsi), verify_node_sharing, &wi);
4593 error ("incorrect sharing of tree nodes");
4594 debug_gimple_stmt (stmt);
4595 debug_generic_expr (addr);
4602 eh_error_found = false;
4603 if (get_eh_throw_stmt_table (cfun))
4604 htab_traverse (get_eh_throw_stmt_table (cfun),
4605 verify_eh_throw_stmt_node,
4608 if (err | eh_error_found)
4609 internal_error ("verify_stmts failed");
4611 pointer_set_destroy (visited);
4612 pointer_set_destroy (visited_stmts);
4613 verify_histograms ();
4614 timevar_pop (TV_TREE_STMT_VERIFY);
4618 /* Verifies that the flow information is OK. */
4621 gimple_verify_flow_info (void)
4625 gimple_stmt_iterator gsi;
4630 if (ENTRY_BLOCK_PTR->il.gimple)
4632 error ("ENTRY_BLOCK has IL associated with it");
4636 if (EXIT_BLOCK_PTR->il.gimple)
4638 error ("EXIT_BLOCK has IL associated with it");
4642 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4643 if (e->flags & EDGE_FALLTHRU)
4645 error ("fallthru to exit from bb %d", e->src->index);
4651 bool found_ctrl_stmt = false;
4655 /* Skip labels on the start of basic block. */
4656 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4659 gimple prev_stmt = stmt;
4661 stmt = gsi_stmt (gsi);
4663 if (gimple_code (stmt) != GIMPLE_LABEL)
4666 label = gimple_label_label (stmt);
4667 if (prev_stmt && DECL_NONLOCAL (label))
4669 error ("nonlocal label ");
4670 print_generic_expr (stderr, label, 0);
4671 fprintf (stderr, " is not first in a sequence of labels in bb %d",
4676 if (label_to_block (label) != bb)
4679 print_generic_expr (stderr, label, 0);
4680 fprintf (stderr, " to block does not match in bb %d",
4685 if (decl_function_context (label) != current_function_decl)
4688 print_generic_expr (stderr, label, 0);
4689 fprintf (stderr, " has incorrect context in bb %d",
4695 /* Verify that body of basic block BB is free of control flow. */
4696 for (; !gsi_end_p (gsi); gsi_next (&gsi))
4698 gimple stmt = gsi_stmt (gsi);
4700 if (found_ctrl_stmt)
4702 error ("control flow in the middle of basic block %d",
4707 if (stmt_ends_bb_p (stmt))
4708 found_ctrl_stmt = true;
4710 if (gimple_code (stmt) == GIMPLE_LABEL)
4713 print_generic_expr (stderr, gimple_label_label (stmt), 0);
4714 fprintf (stderr, " in the middle of basic block %d", bb->index);
4719 gsi = gsi_last_bb (bb);
4720 if (gsi_end_p (gsi))
4723 stmt = gsi_stmt (gsi);
4725 err |= verify_eh_edges (stmt);
4727 if (is_ctrl_stmt (stmt))
4729 FOR_EACH_EDGE (e, ei, bb->succs)
4730 if (e->flags & EDGE_FALLTHRU)
4732 error ("fallthru edge after a control statement in bb %d",
4738 if (gimple_code (stmt) != GIMPLE_COND)
4740 /* Verify that there are no edges with EDGE_TRUE/FALSE_FLAG set
4741 after anything else but if statement. */
4742 FOR_EACH_EDGE (e, ei, bb->succs)
4743 if (e->flags & (EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))
4745 error ("true/false edge after a non-GIMPLE_COND in bb %d",
4751 switch (gimple_code (stmt))
4758 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
4762 || !(true_edge->flags & EDGE_TRUE_VALUE)
4763 || !(false_edge->flags & EDGE_FALSE_VALUE)
4764 || (true_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4765 || (false_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4766 || EDGE_COUNT (bb->succs) >= 3)
4768 error ("wrong outgoing edge flags at end of bb %d",
4776 if (simple_goto_p (stmt))
4778 error ("explicit goto at end of bb %d", bb->index);
4783 /* FIXME. We should double check that the labels in the
4784 destination blocks have their address taken. */
4785 FOR_EACH_EDGE (e, ei, bb->succs)
4786 if ((e->flags & (EDGE_FALLTHRU | EDGE_TRUE_VALUE
4787 | EDGE_FALSE_VALUE))
4788 || !(e->flags & EDGE_ABNORMAL))
4790 error ("wrong outgoing edge flags at end of bb %d",
4798 if (!single_succ_p (bb)
4799 || (single_succ_edge (bb)->flags
4800 & (EDGE_FALLTHRU | EDGE_ABNORMAL
4801 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4803 error ("wrong outgoing edge flags at end of bb %d", bb->index);
4806 if (single_succ (bb) != EXIT_BLOCK_PTR)
4808 error ("return edge does not point to exit in bb %d",
4820 n = gimple_switch_num_labels (stmt);
4822 /* Mark all the destination basic blocks. */
4823 for (i = 0; i < n; ++i)
4825 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4826 basic_block label_bb = label_to_block (lab);
4827 gcc_assert (!label_bb->aux || label_bb->aux == (void *)1);
4828 label_bb->aux = (void *)1;
4831 /* Verify that the case labels are sorted. */
4832 prev = gimple_switch_label (stmt, 0);
4833 for (i = 1; i < n; ++i)
4835 tree c = gimple_switch_label (stmt, i);
4838 error ("found default case not at the start of "
4844 && !tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c)))
4846 error ("case labels not sorted: ");
4847 print_generic_expr (stderr, prev, 0);
4848 fprintf (stderr," is greater than ");
4849 print_generic_expr (stderr, c, 0);
4850 fprintf (stderr," but comes before it.\n");
4855 /* VRP will remove the default case if it can prove it will
4856 never be executed. So do not verify there always exists
4857 a default case here. */
4859 FOR_EACH_EDGE (e, ei, bb->succs)
4863 error ("extra outgoing edge %d->%d",
4864 bb->index, e->dest->index);
4868 e->dest->aux = (void *)2;
4869 if ((e->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL
4870 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4872 error ("wrong outgoing edge flags at end of bb %d",
4878 /* Check that we have all of them. */
4879 for (i = 0; i < n; ++i)
4881 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4882 basic_block label_bb = label_to_block (lab);
4884 if (label_bb->aux != (void *)2)
4886 error ("missing edge %i->%i", bb->index, label_bb->index);
4891 FOR_EACH_EDGE (e, ei, bb->succs)
4892 e->dest->aux = (void *)0;
4899 if (dom_info_state (CDI_DOMINATORS) >= DOM_NO_FAST_QUERY)
4900 verify_dominators (CDI_DOMINATORS);
4906 /* Updates phi nodes after creating a forwarder block joined
4907 by edge FALLTHRU. */
4910 gimple_make_forwarder_block (edge fallthru)
4914 basic_block dummy, bb;
4916 gimple_stmt_iterator gsi;
4918 dummy = fallthru->src;
4919 bb = fallthru->dest;
4921 if (single_pred_p (bb))
4924 /* If we redirected a branch we must create new PHI nodes at the
4926 for (gsi = gsi_start_phis (dummy); !gsi_end_p (gsi); gsi_next (&gsi))
4928 gimple phi, new_phi;
4930 phi = gsi_stmt (gsi);
4931 var = gimple_phi_result (phi);
4932 new_phi = create_phi_node (var, bb);
4933 SSA_NAME_DEF_STMT (var) = new_phi;
4934 gimple_phi_set_result (phi, make_ssa_name (SSA_NAME_VAR (var), phi));
4935 add_phi_arg (new_phi, gimple_phi_result (phi), fallthru,
4939 /* Add the arguments we have stored on edges. */
4940 FOR_EACH_EDGE (e, ei, bb->preds)
4945 flush_pending_stmts (e);
4950 /* Return a non-special label in the head of basic block BLOCK.
4951 Create one if it doesn't exist. */
4954 gimple_block_label (basic_block bb)
4956 gimple_stmt_iterator i, s = gsi_start_bb (bb);
4961 for (i = s; !gsi_end_p (i); first = false, gsi_next (&i))
4963 stmt = gsi_stmt (i);
4964 if (gimple_code (stmt) != GIMPLE_LABEL)
4966 label = gimple_label_label (stmt);
4967 if (!DECL_NONLOCAL (label))
4970 gsi_move_before (&i, &s);
4975 label = create_artificial_label (UNKNOWN_LOCATION);
4976 stmt = gimple_build_label (label);
4977 gsi_insert_before (&s, stmt, GSI_NEW_STMT);
4982 /* Attempt to perform edge redirection by replacing a possibly complex
4983 jump instruction by a goto or by removing the jump completely.
4984 This can apply only if all edges now point to the same block. The
4985 parameters and return values are equivalent to
4986 redirect_edge_and_branch. */
4989 gimple_try_redirect_by_replacing_jump (edge e, basic_block target)
4991 basic_block src = e->src;
4992 gimple_stmt_iterator i;
4995 /* We can replace or remove a complex jump only when we have exactly
4997 if (EDGE_COUNT (src->succs) != 2
4998 /* Verify that all targets will be TARGET. Specifically, the
4999 edge that is not E must also go to TARGET. */
5000 || EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)
5003 i = gsi_last_bb (src);
5007 stmt = gsi_stmt (i);
5009 if (gimple_code (stmt) == GIMPLE_COND || gimple_code (stmt) == GIMPLE_SWITCH)
5011 gsi_remove (&i, true);
5012 e = ssa_redirect_edge (e, target);
5013 e->flags = EDGE_FALLTHRU;
5021 /* Redirect E to DEST. Return NULL on failure. Otherwise, return the
5022 edge representing the redirected branch. */
5025 gimple_redirect_edge_and_branch (edge e, basic_block dest)
5027 basic_block bb = e->src;
5028 gimple_stmt_iterator gsi;
5032 if (e->flags & EDGE_ABNORMAL)
5035 if (e->src != ENTRY_BLOCK_PTR
5036 && (ret = gimple_try_redirect_by_replacing_jump (e, dest)))
5039 if (e->dest == dest)
5042 if (e->flags & EDGE_EH)
5043 return redirect_eh_edge (e, dest);
5045 gsi = gsi_last_bb (bb);
5046 stmt = gsi_end_p (gsi) ? NULL : gsi_stmt (gsi);
5048 switch (stmt ? gimple_code (stmt) : GIMPLE_ERROR_MARK)
5051 /* For COND_EXPR, we only need to redirect the edge. */
5055 /* No non-abnormal edges should lead from a non-simple goto, and
5056 simple ones should be represented implicitly. */
5061 tree label = gimple_block_label (dest);
5062 tree cases = get_cases_for_edge (e, stmt);
5064 /* If we have a list of cases associated with E, then use it
5065 as it's a lot faster than walking the entire case vector. */
5068 edge e2 = find_edge (e->src, dest);
5075 CASE_LABEL (cases) = label;
5076 cases = TREE_CHAIN (cases);
5079 /* If there was already an edge in the CFG, then we need
5080 to move all the cases associated with E to E2. */
5083 tree cases2 = get_cases_for_edge (e2, stmt);
5085 TREE_CHAIN (last) = TREE_CHAIN (cases2);
5086 TREE_CHAIN (cases2) = first;
5091 size_t i, n = gimple_switch_num_labels (stmt);
5093 for (i = 0; i < n; i++)
5095 tree elt = gimple_switch_label (stmt, i);
5096 if (label_to_block (CASE_LABEL (elt)) == e->dest)
5097 CASE_LABEL (elt) = label;
5105 gsi_remove (&gsi, true);
5106 e->flags |= EDGE_FALLTHRU;
5109 case GIMPLE_OMP_RETURN:
5110 case GIMPLE_OMP_CONTINUE:
5111 case GIMPLE_OMP_SECTIONS_SWITCH:
5112 case GIMPLE_OMP_FOR:
5113 /* The edges from OMP constructs can be simply redirected. */
5117 /* Otherwise it must be a fallthru edge, and we don't need to
5118 do anything besides redirecting it. */
5119 gcc_assert (e->flags & EDGE_FALLTHRU);
5123 /* Update/insert PHI nodes as necessary. */
5125 /* Now update the edges in the CFG. */
5126 e = ssa_redirect_edge (e, dest);
5131 /* Returns true if it is possible to remove edge E by redirecting
5132 it to the destination of the other edge from E->src. */
5135 gimple_can_remove_branch_p (const_edge e)
5137 if (e->flags & (EDGE_ABNORMAL | EDGE_EH))
5143 /* Simple wrapper, as we can always redirect fallthru edges. */
5146 gimple_redirect_edge_and_branch_force (edge e, basic_block dest)
5148 e = gimple_redirect_edge_and_branch (e, dest);
5155 /* Splits basic block BB after statement STMT (but at least after the
5156 labels). If STMT is NULL, BB is split just after the labels. */
5159 gimple_split_block (basic_block bb, void *stmt)
5161 gimple_stmt_iterator gsi;
5162 gimple_stmt_iterator gsi_tgt;
5169 new_bb = create_empty_bb (bb);
5171 /* Redirect the outgoing edges. */
5172 new_bb->succs = bb->succs;
5174 FOR_EACH_EDGE (e, ei, new_bb->succs)
5177 if (stmt && gimple_code ((gimple) stmt) == GIMPLE_LABEL)
5180 /* Move everything from GSI to the new basic block. */
5181 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5183 act = gsi_stmt (gsi);
5184 if (gimple_code (act) == GIMPLE_LABEL)
5197 if (gsi_end_p (gsi))
5200 /* Split the statement list - avoid re-creating new containers as this
5201 brings ugly quadratic memory consumption in the inliner.
5202 (We are still quadratic since we need to update stmt BB pointers,
5204 list = gsi_split_seq_before (&gsi);
5205 set_bb_seq (new_bb, list);
5206 for (gsi_tgt = gsi_start (list);
5207 !gsi_end_p (gsi_tgt); gsi_next (&gsi_tgt))
5208 gimple_set_bb (gsi_stmt (gsi_tgt), new_bb);
5214 /* Moves basic block BB after block AFTER. */
5217 gimple_move_block_after (basic_block bb, basic_block after)
5219 if (bb->prev_bb == after)
5223 link_block (bb, after);
5229 /* Return true if basic_block can be duplicated. */
5232 gimple_can_duplicate_bb_p (const_basic_block bb ATTRIBUTE_UNUSED)
5237 /* Create a duplicate of the basic block BB. NOTE: This does not
5238 preserve SSA form. */
5241 gimple_duplicate_bb (basic_block bb)
5244 gimple_stmt_iterator gsi, gsi_tgt;
5245 gimple_seq phis = phi_nodes (bb);
5246 gimple phi, stmt, copy;
5248 new_bb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb);
5250 /* Copy the PHI nodes. We ignore PHI node arguments here because
5251 the incoming edges have not been setup yet. */
5252 for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
5254 phi = gsi_stmt (gsi);
5255 copy = create_phi_node (gimple_phi_result (phi), new_bb);
5256 create_new_def_for (gimple_phi_result (copy), copy,
5257 gimple_phi_result_ptr (copy));
5260 gsi_tgt = gsi_start_bb (new_bb);
5261 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5263 def_operand_p def_p;
5264 ssa_op_iter op_iter;
5267 stmt = gsi_stmt (gsi);
5268 if (gimple_code (stmt) == GIMPLE_LABEL)
5271 /* Create a new copy of STMT and duplicate STMT's virtual
5273 copy = gimple_copy (stmt);
5274 gsi_insert_after (&gsi_tgt, copy, GSI_NEW_STMT);
5275 region = lookup_stmt_eh_region (stmt);
5277 add_stmt_to_eh_region (copy, region);
5278 gimple_duplicate_stmt_histograms (cfun, copy, cfun, stmt);
5280 /* Create new names for all the definitions created by COPY and
5281 add replacement mappings for each new name. */
5282 FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS)
5283 create_new_def_for (DEF_FROM_PTR (def_p), copy, def_p);
5289 /* Adds phi node arguments for edge E_COPY after basic block duplication. */
5292 add_phi_args_after_copy_edge (edge e_copy)
5294 basic_block bb, bb_copy = e_copy->src, dest;
5297 gimple phi, phi_copy;
5299 gimple_stmt_iterator psi, psi_copy;
5301 if (gimple_seq_empty_p (phi_nodes (e_copy->dest)))
5304 bb = bb_copy->flags & BB_DUPLICATED ? get_bb_original (bb_copy) : bb_copy;
5306 if (e_copy->dest->flags & BB_DUPLICATED)
5307 dest = get_bb_original (e_copy->dest);
5309 dest = e_copy->dest;
5311 e = find_edge (bb, dest);
5314 /* During loop unrolling the target of the latch edge is copied.
5315 In this case we are not looking for edge to dest, but to
5316 duplicated block whose original was dest. */
5317 FOR_EACH_EDGE (e, ei, bb->succs)
5319 if ((e->dest->flags & BB_DUPLICATED)
5320 && get_bb_original (e->dest) == dest)
5324 gcc_assert (e != NULL);
5327 for (psi = gsi_start_phis (e->dest),
5328 psi_copy = gsi_start_phis (e_copy->dest);
5330 gsi_next (&psi), gsi_next (&psi_copy))
5332 phi = gsi_stmt (psi);
5333 phi_copy = gsi_stmt (psi_copy);
5334 def = PHI_ARG_DEF_FROM_EDGE (phi, e);
5335 add_phi_arg (phi_copy, def, e_copy,
5336 gimple_phi_arg_location_from_edge (phi, e));
5341 /* Basic block BB_COPY was created by code duplication. Add phi node
5342 arguments for edges going out of BB_COPY. The blocks that were
5343 duplicated have BB_DUPLICATED set. */
5346 add_phi_args_after_copy_bb (basic_block bb_copy)
5351 FOR_EACH_EDGE (e_copy, ei, bb_copy->succs)
5353 add_phi_args_after_copy_edge (e_copy);
5357 /* Blocks in REGION_COPY array of length N_REGION were created by
5358 duplication of basic blocks. Add phi node arguments for edges
5359 going from these blocks. If E_COPY is not NULL, also add
5360 phi node arguments for its destination.*/
5363 add_phi_args_after_copy (basic_block *region_copy, unsigned n_region,
5368 for (i = 0; i < n_region; i++)
5369 region_copy[i]->flags |= BB_DUPLICATED;
5371 for (i = 0; i < n_region; i++)
5372 add_phi_args_after_copy_bb (region_copy[i]);
5374 add_phi_args_after_copy_edge (e_copy);
5376 for (i = 0; i < n_region; i++)
5377 region_copy[i]->flags &= ~BB_DUPLICATED;
5380 /* Duplicates a REGION (set of N_REGION basic blocks) with just a single
5381 important exit edge EXIT. By important we mean that no SSA name defined
5382 inside region is live over the other exit edges of the region. All entry
5383 edges to the region must go to ENTRY->dest. The edge ENTRY is redirected
5384 to the duplicate of the region. SSA form, dominance and loop information
5385 is updated. The new basic blocks are stored to REGION_COPY in the same
5386 order as they had in REGION, provided that REGION_COPY is not NULL.
5387 The function returns false if it is unable to copy the region,
5391 gimple_duplicate_sese_region (edge entry, edge exit,
5392 basic_block *region, unsigned n_region,
5393 basic_block *region_copy)
5396 bool free_region_copy = false, copying_header = false;
5397 struct loop *loop = entry->dest->loop_father;
5399 VEC (basic_block, heap) *doms;
5401 int total_freq = 0, entry_freq = 0;
5402 gcov_type total_count = 0, entry_count = 0;
5404 if (!can_copy_bbs_p (region, n_region))
5407 /* Some sanity checking. Note that we do not check for all possible
5408 missuses of the functions. I.e. if you ask to copy something weird,
5409 it will work, but the state of structures probably will not be
5411 for (i = 0; i < n_region; i++)
5413 /* We do not handle subloops, i.e. all the blocks must belong to the
5415 if (region[i]->loop_father != loop)
5418 if (region[i] != entry->dest
5419 && region[i] == loop->header)
5423 set_loop_copy (loop, loop);
5425 /* In case the function is used for loop header copying (which is the primary
5426 use), ensure that EXIT and its copy will be new latch and entry edges. */
5427 if (loop->header == entry->dest)
5429 copying_header = true;
5430 set_loop_copy (loop, loop_outer (loop));
5432 if (!dominated_by_p (CDI_DOMINATORS, loop->latch, exit->src))
5435 for (i = 0; i < n_region; i++)
5436 if (region[i] != exit->src
5437 && dominated_by_p (CDI_DOMINATORS, region[i], exit->src))
5443 region_copy = XNEWVEC (basic_block, n_region);
5444 free_region_copy = true;
5447 gcc_assert (!need_ssa_update_p (cfun));
5449 /* Record blocks outside the region that are dominated by something
5452 initialize_original_copy_tables ();
5454 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5456 if (entry->dest->count)
5458 total_count = entry->dest->count;
5459 entry_count = entry->count;
5460 /* Fix up corner cases, to avoid division by zero or creation of negative
5462 if (entry_count > total_count)
5463 entry_count = total_count;
5467 total_freq = entry->dest->frequency;
5468 entry_freq = EDGE_FREQUENCY (entry);
5469 /* Fix up corner cases, to avoid division by zero or creation of negative
5471 if (total_freq == 0)
5473 else if (entry_freq > total_freq)
5474 entry_freq = total_freq;
5477 copy_bbs (region, n_region, region_copy, &exit, 1, &exit_copy, loop,
5478 split_edge_bb_loc (entry));
5481 scale_bbs_frequencies_gcov_type (region, n_region,
5482 total_count - entry_count,
5484 scale_bbs_frequencies_gcov_type (region_copy, n_region, entry_count,
5489 scale_bbs_frequencies_int (region, n_region, total_freq - entry_freq,
5491 scale_bbs_frequencies_int (region_copy, n_region, entry_freq, total_freq);
5496 loop->header = exit->dest;
5497 loop->latch = exit->src;
5500 /* Redirect the entry and add the phi node arguments. */
5501 redirected = redirect_edge_and_branch (entry, get_bb_copy (entry->dest));
5502 gcc_assert (redirected != NULL);
5503 flush_pending_stmts (entry);
5505 /* Concerning updating of dominators: We must recount dominators
5506 for entry block and its copy. Anything that is outside of the
5507 region, but was dominated by something inside needs recounting as
5509 set_immediate_dominator (CDI_DOMINATORS, entry->dest, entry->src);
5510 VEC_safe_push (basic_block, heap, doms, get_bb_original (entry->dest));
5511 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5512 VEC_free (basic_block, heap, doms);
5514 /* Add the other PHI node arguments. */
5515 add_phi_args_after_copy (region_copy, n_region, NULL);
5517 /* Update the SSA web. */
5518 update_ssa (TODO_update_ssa);
5520 if (free_region_copy)
5523 free_original_copy_tables ();
5527 /* Duplicates REGION consisting of N_REGION blocks. The new blocks
5528 are stored to REGION_COPY in the same order in that they appear
5529 in REGION, if REGION_COPY is not NULL. ENTRY is the entry to
5530 the region, EXIT an exit from it. The condition guarding EXIT
5531 is moved to ENTRY. Returns true if duplication succeeds, false
5557 gimple_duplicate_sese_tail (edge entry ATTRIBUTE_UNUSED, edge exit ATTRIBUTE_UNUSED,
5558 basic_block *region ATTRIBUTE_UNUSED, unsigned n_region ATTRIBUTE_UNUSED,
5559 basic_block *region_copy ATTRIBUTE_UNUSED)
5562 bool free_region_copy = false;
5563 struct loop *loop = exit->dest->loop_father;
5564 struct loop *orig_loop = entry->dest->loop_father;
5565 basic_block switch_bb, entry_bb, nentry_bb;
5566 VEC (basic_block, heap) *doms;
5567 int total_freq = 0, exit_freq = 0;
5568 gcov_type total_count = 0, exit_count = 0;
5569 edge exits[2], nexits[2], e;
5570 gimple_stmt_iterator gsi;
5574 gcc_assert (EDGE_COUNT (exit->src->succs) == 2);
5576 exits[1] = EDGE_SUCC (exit->src, EDGE_SUCC (exit->src, 0) == exit);
5578 if (!can_copy_bbs_p (region, n_region))
5581 /* Some sanity checking. Note that we do not check for all possible
5582 missuses of the functions. I.e. if you ask to copy something weird
5583 (e.g., in the example, if there is a jump from inside to the middle
5584 of some_code, or come_code defines some of the values used in cond)
5585 it will work, but the resulting code will not be correct. */
5586 for (i = 0; i < n_region; i++)
5588 /* We do not handle subloops, i.e. all the blocks must belong to the
5590 if (region[i]->loop_father != orig_loop)
5593 if (region[i] == orig_loop->latch)
5597 initialize_original_copy_tables ();
5598 set_loop_copy (orig_loop, loop);
5602 region_copy = XNEWVEC (basic_block, n_region);
5603 free_region_copy = true;
5606 gcc_assert (!need_ssa_update_p (cfun));
5608 /* Record blocks outside the region that are dominated by something
5610 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5612 if (exit->src->count)
5614 total_count = exit->src->count;
5615 exit_count = exit->count;
5616 /* Fix up corner cases, to avoid division by zero or creation of negative
5618 if (exit_count > total_count)
5619 exit_count = total_count;
5623 total_freq = exit->src->frequency;
5624 exit_freq = EDGE_FREQUENCY (exit);
5625 /* Fix up corner cases, to avoid division by zero or creation of negative
5627 if (total_freq == 0)
5629 if (exit_freq > total_freq)
5630 exit_freq = total_freq;
5633 copy_bbs (region, n_region, region_copy, exits, 2, nexits, orig_loop,
5634 split_edge_bb_loc (exit));
5637 scale_bbs_frequencies_gcov_type (region, n_region,
5638 total_count - exit_count,
5640 scale_bbs_frequencies_gcov_type (region_copy, n_region, exit_count,
5645 scale_bbs_frequencies_int (region, n_region, total_freq - exit_freq,
5647 scale_bbs_frequencies_int (region_copy, n_region, exit_freq, total_freq);
5650 /* Create the switch block, and put the exit condition to it. */
5651 entry_bb = entry->dest;
5652 nentry_bb = get_bb_copy (entry_bb);
5653 if (!last_stmt (entry->src)
5654 || !stmt_ends_bb_p (last_stmt (entry->src)))
5655 switch_bb = entry->src;
5657 switch_bb = split_edge (entry);
5658 set_immediate_dominator (CDI_DOMINATORS, nentry_bb, switch_bb);
5660 gsi = gsi_last_bb (switch_bb);
5661 cond_stmt = last_stmt (exit->src);
5662 gcc_assert (gimple_code (cond_stmt) == GIMPLE_COND);
5663 cond_stmt = gimple_copy (cond_stmt);
5664 gimple_cond_set_lhs (cond_stmt, unshare_expr (gimple_cond_lhs (cond_stmt)));
5665 gimple_cond_set_rhs (cond_stmt, unshare_expr (gimple_cond_rhs (cond_stmt)));
5666 gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT);
5668 sorig = single_succ_edge (switch_bb);
5669 sorig->flags = exits[1]->flags;
5670 snew = make_edge (switch_bb, nentry_bb, exits[0]->flags);
5672 /* Register the new edge from SWITCH_BB in loop exit lists. */
5673 rescan_loop_exit (snew, true, false);
5675 /* Add the PHI node arguments. */
5676 add_phi_args_after_copy (region_copy, n_region, snew);
5678 /* Get rid of now superfluous conditions and associated edges (and phi node
5680 e = redirect_edge_and_branch (exits[0], exits[1]->dest);
5681 PENDING_STMT (e) = NULL;
5682 e = redirect_edge_and_branch (nexits[1], nexits[0]->dest);
5683 PENDING_STMT (e) = NULL;
5685 /* Anything that is outside of the region, but was dominated by something
5686 inside needs to update dominance info. */
5687 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5688 VEC_free (basic_block, heap, doms);
5690 /* Update the SSA web. */
5691 update_ssa (TODO_update_ssa);
5693 if (free_region_copy)
5696 free_original_copy_tables ();
5700 /* Add all the blocks dominated by ENTRY to the array BBS_P. Stop
5701 adding blocks when the dominator traversal reaches EXIT. This
5702 function silently assumes that ENTRY strictly dominates EXIT. */
5705 gather_blocks_in_sese_region (basic_block entry, basic_block exit,
5706 VEC(basic_block,heap) **bbs_p)
5710 for (son = first_dom_son (CDI_DOMINATORS, entry);
5712 son = next_dom_son (CDI_DOMINATORS, son))
5714 VEC_safe_push (basic_block, heap, *bbs_p, son);
5716 gather_blocks_in_sese_region (son, exit, bbs_p);
5720 /* Replaces *TP with a duplicate (belonging to function TO_CONTEXT).
5721 The duplicates are recorded in VARS_MAP. */
5724 replace_by_duplicate_decl (tree *tp, struct pointer_map_t *vars_map,
5727 tree t = *tp, new_t;
5728 struct function *f = DECL_STRUCT_FUNCTION (to_context);
5731 if (DECL_CONTEXT (t) == to_context)
5734 loc = pointer_map_contains (vars_map, t);
5738 loc = pointer_map_insert (vars_map, t);
5742 new_t = copy_var_decl (t, DECL_NAME (t), TREE_TYPE (t));
5743 f->local_decls = tree_cons (NULL_TREE, new_t, f->local_decls);
5747 gcc_assert (TREE_CODE (t) == CONST_DECL);
5748 new_t = copy_node (t);
5750 DECL_CONTEXT (new_t) = to_context;
5755 new_t = (tree) *loc;
5761 /* Creates an ssa name in TO_CONTEXT equivalent to NAME.
5762 VARS_MAP maps old ssa names and var_decls to the new ones. */
5765 replace_ssa_name (tree name, struct pointer_map_t *vars_map,
5769 tree new_name, decl = SSA_NAME_VAR (name);
5771 gcc_assert (is_gimple_reg (name));
5773 loc = pointer_map_contains (vars_map, name);
5777 replace_by_duplicate_decl (&decl, vars_map, to_context);
5779 push_cfun (DECL_STRUCT_FUNCTION (to_context));
5780 if (gimple_in_ssa_p (cfun))
5781 add_referenced_var (decl);
5783 new_name = make_ssa_name (decl, SSA_NAME_DEF_STMT (name));
5784 if (SSA_NAME_IS_DEFAULT_DEF (name))
5785 set_default_def (decl, new_name);
5788 loc = pointer_map_insert (vars_map, name);
5792 new_name = (tree) *loc;
5803 struct pointer_map_t *vars_map;
5804 htab_t new_label_map;
5808 /* Helper for move_block_to_fn. Set TREE_BLOCK in every expression
5809 contained in *TP if it has been ORIG_BLOCK previously and change the
5810 DECL_CONTEXT of every local variable referenced in *TP. */
5813 move_stmt_op (tree *tp, int *walk_subtrees, void *data)
5815 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
5816 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5820 /* We should never have TREE_BLOCK set on non-statements. */
5821 gcc_assert (!TREE_BLOCK (t));
5823 else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
5825 if (TREE_CODE (t) == SSA_NAME)
5826 *tp = replace_ssa_name (t, p->vars_map, p->to_context);
5827 else if (TREE_CODE (t) == LABEL_DECL)
5829 if (p->new_label_map)
5831 struct tree_map in, *out;
5833 out = (struct tree_map *)
5834 htab_find_with_hash (p->new_label_map, &in, DECL_UID (t));
5839 DECL_CONTEXT (t) = p->to_context;
5841 else if (p->remap_decls_p)
5843 /* Replace T with its duplicate. T should no longer appear in the
5844 parent function, so this looks wasteful; however, it may appear
5845 in referenced_vars, and more importantly, as virtual operands of
5846 statements, and in alias lists of other variables. It would be
5847 quite difficult to expunge it from all those places. ??? It might
5848 suffice to do this for addressable variables. */
5849 if ((TREE_CODE (t) == VAR_DECL
5850 && !is_global_var (t))
5851 || TREE_CODE (t) == CONST_DECL)
5852 replace_by_duplicate_decl (tp, p->vars_map, p->to_context);
5855 && gimple_in_ssa_p (cfun))
5857 push_cfun (DECL_STRUCT_FUNCTION (p->to_context));
5858 add_referenced_var (*tp);
5864 else if (TYPE_P (t))
5870 /* Like move_stmt_op, but for gimple statements.
5872 Helper for move_block_to_fn. Set GIMPLE_BLOCK in every expression
5873 contained in the current statement in *GSI_P and change the
5874 DECL_CONTEXT of every local variable referenced in the current
5878 move_stmt_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
5879 struct walk_stmt_info *wi)
5881 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5882 gimple stmt = gsi_stmt (*gsi_p);
5883 tree block = gimple_block (stmt);
5885 if (p->orig_block == NULL_TREE
5886 || block == p->orig_block
5887 || block == NULL_TREE)
5888 gimple_set_block (stmt, p->new_block);
5889 #ifdef ENABLE_CHECKING
5890 else if (block != p->new_block)
5892 while (block && block != p->orig_block)
5893 block = BLOCK_SUPERCONTEXT (block);
5898 if (is_gimple_omp (stmt)
5899 && gimple_code (stmt) != GIMPLE_OMP_RETURN
5900 && gimple_code (stmt) != GIMPLE_OMP_CONTINUE)
5902 /* Do not remap variables inside OMP directives. Variables
5903 referenced in clauses and directive header belong to the
5904 parent function and should not be moved into the child
5906 bool save_remap_decls_p = p->remap_decls_p;
5907 p->remap_decls_p = false;
5908 *handled_ops_p = true;
5910 walk_gimple_seq (gimple_omp_body (stmt), move_stmt_r, move_stmt_op, wi);
5912 p->remap_decls_p = save_remap_decls_p;
5918 /* Marks virtual operands of all statements in basic blocks BBS for
5922 mark_virtual_ops_in_bb (basic_block bb)
5924 gimple_stmt_iterator gsi;
5926 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5927 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5929 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5930 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
5933 /* Move basic block BB from function CFUN to function DEST_FN. The
5934 block is moved out of the original linked list and placed after
5935 block AFTER in the new list. Also, the block is removed from the
5936 original array of blocks and placed in DEST_FN's array of blocks.
5937 If UPDATE_EDGE_COUNT_P is true, the edge counts on both CFGs is
5938 updated to reflect the moved edges.
5940 The local variables are remapped to new instances, VARS_MAP is used
5941 to record the mapping. */
5944 move_block_to_fn (struct function *dest_cfun, basic_block bb,
5945 basic_block after, bool update_edge_count_p,
5946 struct move_stmt_d *d, int eh_offset)
5948 struct control_flow_graph *cfg;
5951 gimple_stmt_iterator si;
5952 unsigned old_len, new_len;
5954 /* Remove BB from dominance structures. */
5955 delete_from_dominance_info (CDI_DOMINATORS, bb);
5957 remove_bb_from_loops (bb);
5959 /* Link BB to the new linked list. */
5960 move_block_after (bb, after);
5962 /* Update the edge count in the corresponding flowgraphs. */
5963 if (update_edge_count_p)
5964 FOR_EACH_EDGE (e, ei, bb->succs)
5966 cfun->cfg->x_n_edges--;
5967 dest_cfun->cfg->x_n_edges++;
5970 /* Remove BB from the original basic block array. */
5971 VEC_replace (basic_block, cfun->cfg->x_basic_block_info, bb->index, NULL);
5972 cfun->cfg->x_n_basic_blocks--;
5974 /* Grow DEST_CFUN's basic block array if needed. */
5975 cfg = dest_cfun->cfg;
5976 cfg->x_n_basic_blocks++;
5977 if (bb->index >= cfg->x_last_basic_block)
5978 cfg->x_last_basic_block = bb->index + 1;
5980 old_len = VEC_length (basic_block, cfg->x_basic_block_info);
5981 if ((unsigned) cfg->x_last_basic_block >= old_len)
5983 new_len = cfg->x_last_basic_block + (cfg->x_last_basic_block + 3) / 4;
5984 VEC_safe_grow_cleared (basic_block, gc, cfg->x_basic_block_info,
5988 VEC_replace (basic_block, cfg->x_basic_block_info,
5991 /* Remap the variables in phi nodes. */
5992 for (si = gsi_start_phis (bb); !gsi_end_p (si); )
5994 gimple phi = gsi_stmt (si);
5996 tree op = PHI_RESULT (phi);
5999 if (!is_gimple_reg (op))
6001 /* Remove the phi nodes for virtual operands (alias analysis will be
6002 run for the new function, anyway). */
6003 remove_phi_node (&si, true);
6007 SET_PHI_RESULT (phi,
6008 replace_ssa_name (op, d->vars_map, dest_cfun->decl));
6009 FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
6011 op = USE_FROM_PTR (use);
6012 if (TREE_CODE (op) == SSA_NAME)
6013 SET_USE (use, replace_ssa_name (op, d->vars_map, dest_cfun->decl));
6019 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
6021 gimple stmt = gsi_stmt (si);
6023 struct walk_stmt_info wi;
6025 memset (&wi, 0, sizeof (wi));
6027 walk_gimple_stmt (&si, move_stmt_r, move_stmt_op, &wi);
6029 if (gimple_code (stmt) == GIMPLE_LABEL)
6031 tree label = gimple_label_label (stmt);
6032 int uid = LABEL_DECL_UID (label);
6034 gcc_assert (uid > -1);
6036 old_len = VEC_length (basic_block, cfg->x_label_to_block_map);
6037 if (old_len <= (unsigned) uid)
6039 new_len = 3 * uid / 2 + 1;
6040 VEC_safe_grow_cleared (basic_block, gc,
6041 cfg->x_label_to_block_map, new_len);
6044 VEC_replace (basic_block, cfg->x_label_to_block_map, uid, bb);
6045 VEC_replace (basic_block, cfun->cfg->x_label_to_block_map, uid, NULL);
6047 gcc_assert (DECL_CONTEXT (label) == dest_cfun->decl);
6049 if (uid >= dest_cfun->cfg->last_label_uid)
6050 dest_cfun->cfg->last_label_uid = uid + 1;
6052 else if (gimple_code (stmt) == GIMPLE_RESX && eh_offset != 0)
6053 gimple_resx_set_region (stmt, gimple_resx_region (stmt) + eh_offset);
6055 region = lookup_stmt_eh_region (stmt);
6058 add_stmt_to_eh_region_fn (dest_cfun, stmt, region + eh_offset);
6059 remove_stmt_from_eh_region (stmt);
6060 gimple_duplicate_stmt_histograms (dest_cfun, stmt, cfun, stmt);
6061 gimple_remove_stmt_histograms (cfun, stmt);
6064 /* We cannot leave any operands allocated from the operand caches of
6065 the current function. */
6066 free_stmt_operands (stmt);
6067 push_cfun (dest_cfun);
6072 FOR_EACH_EDGE (e, ei, bb->succs)
6075 tree block = e->goto_block;
6076 if (d->orig_block == NULL_TREE
6077 || block == d->orig_block)
6078 e->goto_block = d->new_block;
6079 #ifdef ENABLE_CHECKING
6080 else if (block != d->new_block)
6082 while (block && block != d->orig_block)
6083 block = BLOCK_SUPERCONTEXT (block);
6090 /* Examine the statements in BB (which is in SRC_CFUN); find and return
6091 the outermost EH region. Use REGION as the incoming base EH region. */
6094 find_outermost_region_in_block (struct function *src_cfun,
6095 basic_block bb, int region)
6097 gimple_stmt_iterator si;
6099 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
6101 gimple stmt = gsi_stmt (si);
6104 if (gimple_code (stmt) == GIMPLE_RESX)
6105 stmt_region = gimple_resx_region (stmt);
6107 stmt_region = lookup_stmt_eh_region_fn (src_cfun, stmt);
6108 if (stmt_region > 0)
6111 region = stmt_region;
6112 else if (stmt_region != region)
6114 region = eh_region_outermost (src_cfun, stmt_region, region);
6115 gcc_assert (region != -1);
6124 new_label_mapper (tree decl, void *data)
6126 htab_t hash = (htab_t) data;
6130 gcc_assert (TREE_CODE (decl) == LABEL_DECL);
6132 m = XNEW (struct tree_map);
6133 m->hash = DECL_UID (decl);
6134 m->base.from = decl;
6135 m->to = create_artificial_label (UNKNOWN_LOCATION);
6136 LABEL_DECL_UID (m->to) = LABEL_DECL_UID (decl);
6137 if (LABEL_DECL_UID (m->to) >= cfun->cfg->last_label_uid)
6138 cfun->cfg->last_label_uid = LABEL_DECL_UID (m->to) + 1;
6140 slot = htab_find_slot_with_hash (hash, m, m->hash, INSERT);
6141 gcc_assert (*slot == NULL);
6148 /* Change DECL_CONTEXT of all BLOCK_VARS in block, including
6152 replace_block_vars_by_duplicates (tree block, struct pointer_map_t *vars_map,
6157 for (tp = &BLOCK_VARS (block); *tp; tp = &TREE_CHAIN (*tp))
6160 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != CONST_DECL)
6162 replace_by_duplicate_decl (&t, vars_map, to_context);
6165 if (TREE_CODE (*tp) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (*tp))
6167 SET_DECL_VALUE_EXPR (t, DECL_VALUE_EXPR (*tp));
6168 DECL_HAS_VALUE_EXPR_P (t) = 1;
6170 TREE_CHAIN (t) = TREE_CHAIN (*tp);
6175 for (block = BLOCK_SUBBLOCKS (block); block; block = BLOCK_CHAIN (block))
6176 replace_block_vars_by_duplicates (block, vars_map, to_context);
6179 /* Move a single-entry, single-exit region delimited by ENTRY_BB and
6180 EXIT_BB to function DEST_CFUN. The whole region is replaced by a
6181 single basic block in the original CFG and the new basic block is
6182 returned. DEST_CFUN must not have a CFG yet.
6184 Note that the region need not be a pure SESE region. Blocks inside
6185 the region may contain calls to abort/exit. The only restriction
6186 is that ENTRY_BB should be the only entry point and it must
6189 Change TREE_BLOCK of all statements in ORIG_BLOCK to the new
6190 functions outermost BLOCK, move all subblocks of ORIG_BLOCK
6191 to the new function.
6193 All local variables referenced in the region are assumed to be in
6194 the corresponding BLOCK_VARS and unexpanded variable lists
6195 associated with DEST_CFUN. */
6198 move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb,
6199 basic_block exit_bb, tree orig_block)
6201 VEC(basic_block,heap) *bbs, *dom_bbs;
6202 basic_block dom_entry = get_immediate_dominator (CDI_DOMINATORS, entry_bb);
6203 basic_block after, bb, *entry_pred, *exit_succ, abb;
6204 struct function *saved_cfun = cfun;
6205 int *entry_flag, *exit_flag, eh_offset;
6206 unsigned *entry_prob, *exit_prob;
6207 unsigned i, num_entry_edges, num_exit_edges;
6210 htab_t new_label_map;
6211 struct pointer_map_t *vars_map;
6212 struct loop *loop = entry_bb->loop_father;
6213 struct move_stmt_d d;
6215 /* If ENTRY does not strictly dominate EXIT, this cannot be an SESE
6217 gcc_assert (entry_bb != exit_bb
6219 || dominated_by_p (CDI_DOMINATORS, exit_bb, entry_bb)));
6221 /* Collect all the blocks in the region. Manually add ENTRY_BB
6222 because it won't be added by dfs_enumerate_from. */
6224 VEC_safe_push (basic_block, heap, bbs, entry_bb);
6225 gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs);
6227 /* The blocks that used to be dominated by something in BBS will now be
6228 dominated by the new block. */
6229 dom_bbs = get_dominated_by_region (CDI_DOMINATORS,
6230 VEC_address (basic_block, bbs),
6231 VEC_length (basic_block, bbs));
6233 /* Detach ENTRY_BB and EXIT_BB from CFUN->CFG. We need to remember
6234 the predecessor edges to ENTRY_BB and the successor edges to
6235 EXIT_BB so that we can re-attach them to the new basic block that
6236 will replace the region. */
6237 num_entry_edges = EDGE_COUNT (entry_bb->preds);
6238 entry_pred = (basic_block *) xcalloc (num_entry_edges, sizeof (basic_block));
6239 entry_flag = (int *) xcalloc (num_entry_edges, sizeof (int));
6240 entry_prob = XNEWVEC (unsigned, num_entry_edges);
6242 for (ei = ei_start (entry_bb->preds); (e = ei_safe_edge (ei)) != NULL;)
6244 entry_prob[i] = e->probability;
6245 entry_flag[i] = e->flags;
6246 entry_pred[i++] = e->src;
6252 num_exit_edges = EDGE_COUNT (exit_bb->succs);
6253 exit_succ = (basic_block *) xcalloc (num_exit_edges,
6254 sizeof (basic_block));
6255 exit_flag = (int *) xcalloc (num_exit_edges, sizeof (int));
6256 exit_prob = XNEWVEC (unsigned, num_exit_edges);
6258 for (ei = ei_start (exit_bb->succs); (e = ei_safe_edge (ei)) != NULL;)
6260 exit_prob[i] = e->probability;
6261 exit_flag[i] = e->flags;
6262 exit_succ[i++] = e->dest;
6274 /* Switch context to the child function to initialize DEST_FN's CFG. */
6275 gcc_assert (dest_cfun->cfg == NULL);
6276 push_cfun (dest_cfun);
6278 init_empty_tree_cfg ();
6280 /* Initialize EH information for the new function. */
6282 new_label_map = NULL;
6287 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6288 region = find_outermost_region_in_block (saved_cfun, bb, region);
6290 init_eh_for_function ();
6293 new_label_map = htab_create (17, tree_map_hash, tree_map_eq, free);
6294 eh_offset = duplicate_eh_regions (saved_cfun, new_label_mapper,
6295 new_label_map, region, 0);
6301 /* Move blocks from BBS into DEST_CFUN. */
6302 gcc_assert (VEC_length (basic_block, bbs) >= 2);
6303 after = dest_cfun->cfg->x_entry_block_ptr;
6304 vars_map = pointer_map_create ();
6306 memset (&d, 0, sizeof (d));
6307 d.vars_map = vars_map;
6308 d.from_context = cfun->decl;
6309 d.to_context = dest_cfun->decl;
6310 d.new_label_map = new_label_map;
6311 d.remap_decls_p = true;
6312 d.orig_block = orig_block;
6313 d.new_block = DECL_INITIAL (dest_cfun->decl);
6315 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6317 /* No need to update edge counts on the last block. It has
6318 already been updated earlier when we detached the region from
6319 the original CFG. */
6320 move_block_to_fn (dest_cfun, bb, after, bb != exit_bb, &d, eh_offset);
6324 /* Rewire BLOCK_SUBBLOCKS of orig_block. */
6328 gcc_assert (BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6330 BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6331 = BLOCK_SUBBLOCKS (orig_block);
6332 for (block = BLOCK_SUBBLOCKS (orig_block);
6333 block; block = BLOCK_CHAIN (block))
6334 BLOCK_SUPERCONTEXT (block) = DECL_INITIAL (dest_cfun->decl);
6335 BLOCK_SUBBLOCKS (orig_block) = NULL_TREE;
6338 replace_block_vars_by_duplicates (DECL_INITIAL (dest_cfun->decl),
6339 vars_map, dest_cfun->decl);
6342 htab_delete (new_label_map);
6343 pointer_map_destroy (vars_map);
6345 /* Rewire the entry and exit blocks. The successor to the entry
6346 block turns into the successor of DEST_FN's ENTRY_BLOCK_PTR in
6347 the child function. Similarly, the predecessor of DEST_FN's
6348 EXIT_BLOCK_PTR turns into the predecessor of EXIT_BLOCK_PTR. We
6349 need to switch CFUN between DEST_CFUN and SAVED_CFUN so that the
6350 various CFG manipulation function get to the right CFG.
6352 FIXME, this is silly. The CFG ought to become a parameter to
6354 push_cfun (dest_cfun);
6355 make_edge (ENTRY_BLOCK_PTR, entry_bb, EDGE_FALLTHRU);
6357 make_edge (exit_bb, EXIT_BLOCK_PTR, 0);
6360 /* Back in the original function, the SESE region has disappeared,
6361 create a new basic block in its place. */
6362 bb = create_empty_bb (entry_pred[0]);
6364 add_bb_to_loop (bb, loop);
6365 for (i = 0; i < num_entry_edges; i++)
6367 e = make_edge (entry_pred[i], bb, entry_flag[i]);
6368 e->probability = entry_prob[i];
6371 for (i = 0; i < num_exit_edges; i++)
6373 e = make_edge (bb, exit_succ[i], exit_flag[i]);
6374 e->probability = exit_prob[i];
6377 set_immediate_dominator (CDI_DOMINATORS, bb, dom_entry);
6378 for (i = 0; VEC_iterate (basic_block, dom_bbs, i, abb); i++)
6379 set_immediate_dominator (CDI_DOMINATORS, abb, bb);
6380 VEC_free (basic_block, heap, dom_bbs);
6391 VEC_free (basic_block, heap, bbs);
6397 /* Dump FUNCTION_DECL FN to file FILE using FLAGS (see TDF_* in tree-pass.h)
6401 dump_function_to_file (tree fn, FILE *file, int flags)
6403 tree arg, vars, var;
6404 struct function *dsf;
6405 bool ignore_topmost_bind = false, any_var = false;
6409 fprintf (file, "%s (", lang_hooks.decl_printable_name (fn, 2));
6411 arg = DECL_ARGUMENTS (fn);
6414 print_generic_expr (file, TREE_TYPE (arg), dump_flags);
6415 fprintf (file, " ");
6416 print_generic_expr (file, arg, dump_flags);
6417 if (flags & TDF_VERBOSE)
6418 print_node (file, "", arg, 4);
6419 if (TREE_CHAIN (arg))
6420 fprintf (file, ", ");
6421 arg = TREE_CHAIN (arg);
6423 fprintf (file, ")\n");
6425 if (flags & TDF_VERBOSE)
6426 print_node (file, "", fn, 2);
6428 dsf = DECL_STRUCT_FUNCTION (fn);
6429 if (dsf && (flags & TDF_DETAILS))
6430 dump_eh_tree (file, dsf);
6432 if (flags & TDF_RAW && !gimple_has_body_p (fn))
6434 dump_node (fn, TDF_SLIM | flags, file);
6438 /* Switch CFUN to point to FN. */
6439 push_cfun (DECL_STRUCT_FUNCTION (fn));
6441 /* When GIMPLE is lowered, the variables are no longer available in
6442 BIND_EXPRs, so display them separately. */
6443 if (cfun && cfun->decl == fn && cfun->local_decls)
6445 ignore_topmost_bind = true;
6447 fprintf (file, "{\n");
6448 for (vars = cfun->local_decls; vars; vars = TREE_CHAIN (vars))
6450 var = TREE_VALUE (vars);
6452 print_generic_decl (file, var, flags);
6453 if (flags & TDF_VERBOSE)
6454 print_node (file, "", var, 4);
6455 fprintf (file, "\n");
6461 if (cfun && cfun->decl == fn && cfun->cfg && basic_block_info)
6463 /* If the CFG has been built, emit a CFG-based dump. */
6464 check_bb_profile (ENTRY_BLOCK_PTR, file);
6465 if (!ignore_topmost_bind)
6466 fprintf (file, "{\n");
6468 if (any_var && n_basic_blocks)
6469 fprintf (file, "\n");
6472 gimple_dump_bb (bb, file, 2, flags);
6474 fprintf (file, "}\n");
6475 check_bb_profile (EXIT_BLOCK_PTR, file);
6477 else if (DECL_SAVED_TREE (fn) == NULL)
6479 /* The function is now in GIMPLE form but the CFG has not been
6480 built yet. Emit the single sequence of GIMPLE statements
6481 that make up its body. */
6482 gimple_seq body = gimple_body (fn);
6484 if (gimple_seq_first_stmt (body)
6485 && gimple_seq_first_stmt (body) == gimple_seq_last_stmt (body)
6486 && gimple_code (gimple_seq_first_stmt (body)) == GIMPLE_BIND)
6487 print_gimple_seq (file, body, 0, flags);
6490 if (!ignore_topmost_bind)
6491 fprintf (file, "{\n");
6494 fprintf (file, "\n");
6496 print_gimple_seq (file, body, 2, flags);
6497 fprintf (file, "}\n");
6504 /* Make a tree based dump. */
6505 chain = DECL_SAVED_TREE (fn);
6507 if (chain && TREE_CODE (chain) == BIND_EXPR)
6509 if (ignore_topmost_bind)
6511 chain = BIND_EXPR_BODY (chain);
6519 if (!ignore_topmost_bind)
6520 fprintf (file, "{\n");
6525 fprintf (file, "\n");
6527 print_generic_stmt_indented (file, chain, flags, indent);
6528 if (ignore_topmost_bind)
6529 fprintf (file, "}\n");
6532 fprintf (file, "\n\n");
6539 /* Dump FUNCTION_DECL FN to stderr using FLAGS (see TDF_* in tree.h) */
6542 debug_function (tree fn, int flags)
6544 dump_function_to_file (fn, stderr, flags);
6548 /* Print on FILE the indexes for the predecessors of basic_block BB. */
6551 print_pred_bbs (FILE *file, basic_block bb)
6556 FOR_EACH_EDGE (e, ei, bb->preds)
6557 fprintf (file, "bb_%d ", e->src->index);
6561 /* Print on FILE the indexes for the successors of basic_block BB. */
6564 print_succ_bbs (FILE *file, basic_block bb)
6569 FOR_EACH_EDGE (e, ei, bb->succs)
6570 fprintf (file, "bb_%d ", e->dest->index);
6573 /* Print to FILE the basic block BB following the VERBOSITY level. */
6576 print_loops_bb (FILE *file, basic_block bb, int indent, int verbosity)
6578 char *s_indent = (char *) alloca ((size_t) indent + 1);
6579 memset ((void *) s_indent, ' ', (size_t) indent);
6580 s_indent[indent] = '\0';
6582 /* Print basic_block's header. */
6585 fprintf (file, "%s bb_%d (preds = {", s_indent, bb->index);
6586 print_pred_bbs (file, bb);
6587 fprintf (file, "}, succs = {");
6588 print_succ_bbs (file, bb);
6589 fprintf (file, "})\n");
6592 /* Print basic_block's body. */
6595 fprintf (file, "%s {\n", s_indent);
6596 gimple_dump_bb (bb, file, indent + 4, TDF_VOPS|TDF_MEMSYMS);
6597 fprintf (file, "%s }\n", s_indent);
6601 static void print_loop_and_siblings (FILE *, struct loop *, int, int);
6603 /* Pretty print LOOP on FILE, indented INDENT spaces. Following
6604 VERBOSITY level this outputs the contents of the loop, or just its
6608 print_loop (FILE *file, struct loop *loop, int indent, int verbosity)
6616 s_indent = (char *) alloca ((size_t) indent + 1);
6617 memset ((void *) s_indent, ' ', (size_t) indent);
6618 s_indent[indent] = '\0';
6620 /* Print loop's header. */
6621 fprintf (file, "%sloop_%d (header = %d, latch = %d", s_indent,
6622 loop->num, loop->header->index, loop->latch->index);
6623 fprintf (file, ", niter = ");
6624 print_generic_expr (file, loop->nb_iterations, 0);
6626 if (loop->any_upper_bound)
6628 fprintf (file, ", upper_bound = ");
6629 dump_double_int (file, loop->nb_iterations_upper_bound, true);
6632 if (loop->any_estimate)
6634 fprintf (file, ", estimate = ");
6635 dump_double_int (file, loop->nb_iterations_estimate, true);
6637 fprintf (file, ")\n");
6639 /* Print loop's body. */
6642 fprintf (file, "%s{\n", s_indent);
6644 if (bb->loop_father == loop)
6645 print_loops_bb (file, bb, indent, verbosity);
6647 print_loop_and_siblings (file, loop->inner, indent + 2, verbosity);
6648 fprintf (file, "%s}\n", s_indent);
6652 /* Print the LOOP and its sibling loops on FILE, indented INDENT
6653 spaces. Following VERBOSITY level this outputs the contents of the
6654 loop, or just its structure. */
6657 print_loop_and_siblings (FILE *file, struct loop *loop, int indent, int verbosity)
6662 print_loop (file, loop, indent, verbosity);
6663 print_loop_and_siblings (file, loop->next, indent, verbosity);
6666 /* Follow a CFG edge from the entry point of the program, and on entry
6667 of a loop, pretty print the loop structure on FILE. */
6670 print_loops (FILE *file, int verbosity)
6674 bb = ENTRY_BLOCK_PTR;
6675 if (bb && bb->loop_father)
6676 print_loop_and_siblings (file, bb->loop_father, 0, verbosity);
6680 /* Debugging loops structure at tree level, at some VERBOSITY level. */
6683 debug_loops (int verbosity)
6685 print_loops (stderr, verbosity);
6688 /* Print on stderr the code of LOOP, at some VERBOSITY level. */
6691 debug_loop (struct loop *loop, int verbosity)
6693 print_loop (stderr, loop, 0, verbosity);
6696 /* Print on stderr the code of loop number NUM, at some VERBOSITY
6700 debug_loop_num (unsigned num, int verbosity)
6702 debug_loop (get_loop (num), verbosity);
6705 /* Return true if BB ends with a call, possibly followed by some
6706 instructions that must stay with the call. Return false,
6710 gimple_block_ends_with_call_p (basic_block bb)
6712 gimple_stmt_iterator gsi = gsi_last_nondebug_bb (bb);
6713 return is_gimple_call (gsi_stmt (gsi));
6717 /* Return true if BB ends with a conditional branch. Return false,
6721 gimple_block_ends_with_condjump_p (const_basic_block bb)
6723 gimple stmt = last_stmt (CONST_CAST_BB (bb));
6724 return (stmt && gimple_code (stmt) == GIMPLE_COND);
6728 /* Return true if we need to add fake edge to exit at statement T.
6729 Helper function for gimple_flow_call_edges_add. */
6732 need_fake_edge_p (gimple t)
6734 tree fndecl = NULL_TREE;
6737 /* NORETURN and LONGJMP calls already have an edge to exit.
6738 CONST and PURE calls do not need one.
6739 We don't currently check for CONST and PURE here, although
6740 it would be a good idea, because those attributes are
6741 figured out from the RTL in mark_constant_function, and
6742 the counter incrementation code from -fprofile-arcs
6743 leads to different results from -fbranch-probabilities. */
6744 if (is_gimple_call (t))
6746 fndecl = gimple_call_fndecl (t);
6747 call_flags = gimple_call_flags (t);
6750 if (is_gimple_call (t)
6752 && DECL_BUILT_IN (fndecl)
6753 && (call_flags & ECF_NOTHROW)
6754 && !(call_flags & ECF_RETURNS_TWICE)
6755 /* fork() doesn't really return twice, but the effect of
6756 wrapping it in __gcov_fork() which calls __gcov_flush()
6757 and clears the counters before forking has the same
6758 effect as returning twice. Force a fake edge. */
6759 && !(DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6760 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_FORK))
6763 if (is_gimple_call (t)
6764 && !(call_flags & ECF_NORETURN))
6767 if (gimple_code (t) == GIMPLE_ASM
6768 && (gimple_asm_volatile_p (t) || gimple_asm_input_p (t)))
6775 /* Add fake edges to the function exit for any non constant and non
6776 noreturn calls, volatile inline assembly in the bitmap of blocks
6777 specified by BLOCKS or to the whole CFG if BLOCKS is zero. Return
6778 the number of blocks that were split.
6780 The goal is to expose cases in which entering a basic block does
6781 not imply that all subsequent instructions must be executed. */
6784 gimple_flow_call_edges_add (sbitmap blocks)
6787 int blocks_split = 0;
6788 int last_bb = last_basic_block;
6789 bool check_last_block = false;
6791 if (n_basic_blocks == NUM_FIXED_BLOCKS)
6795 check_last_block = true;
6797 check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index);
6799 /* In the last basic block, before epilogue generation, there will be
6800 a fallthru edge to EXIT. Special care is required if the last insn
6801 of the last basic block is a call because make_edge folds duplicate
6802 edges, which would result in the fallthru edge also being marked
6803 fake, which would result in the fallthru edge being removed by
6804 remove_fake_edges, which would result in an invalid CFG.
6806 Moreover, we can't elide the outgoing fake edge, since the block
6807 profiler needs to take this into account in order to solve the minimal
6808 spanning tree in the case that the call doesn't return.
6810 Handle this by adding a dummy instruction in a new last basic block. */
6811 if (check_last_block)
6813 basic_block bb = EXIT_BLOCK_PTR->prev_bb;
6814 gimple_stmt_iterator gsi = gsi_last_bb (bb);
6817 if (!gsi_end_p (gsi))
6820 if (t && need_fake_edge_p (t))
6824 e = find_edge (bb, EXIT_BLOCK_PTR);
6827 gsi_insert_on_edge (e, gimple_build_nop ());
6828 gsi_commit_edge_inserts ();
6833 /* Now add fake edges to the function exit for any non constant
6834 calls since there is no way that we can determine if they will
6836 for (i = 0; i < last_bb; i++)
6838 basic_block bb = BASIC_BLOCK (i);
6839 gimple_stmt_iterator gsi;
6840 gimple stmt, last_stmt;
6845 if (blocks && !TEST_BIT (blocks, i))
6848 gsi = gsi_last_bb (bb);
6849 if (!gsi_end_p (gsi))
6851 last_stmt = gsi_stmt (gsi);
6854 stmt = gsi_stmt (gsi);
6855 if (need_fake_edge_p (stmt))
6859 /* The handling above of the final block before the
6860 epilogue should be enough to verify that there is
6861 no edge to the exit block in CFG already.
6862 Calling make_edge in such case would cause us to
6863 mark that edge as fake and remove it later. */
6864 #ifdef ENABLE_CHECKING
6865 if (stmt == last_stmt)
6867 e = find_edge (bb, EXIT_BLOCK_PTR);
6868 gcc_assert (e == NULL);
6872 /* Note that the following may create a new basic block
6873 and renumber the existing basic blocks. */
6874 if (stmt != last_stmt)
6876 e = split_block (bb, stmt);
6880 make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE);
6884 while (!gsi_end_p (gsi));
6889 verify_flow_info ();
6891 return blocks_split;
6894 /* Purge dead abnormal call edges from basic block BB. */
6897 gimple_purge_dead_abnormal_call_edges (basic_block bb)
6899 bool changed = gimple_purge_dead_eh_edges (bb);
6901 if (cfun->has_nonlocal_label)
6903 gimple stmt = last_stmt (bb);
6907 if (!(stmt && stmt_can_make_abnormal_goto (stmt)))
6908 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
6910 if (e->flags & EDGE_ABNORMAL)
6919 /* See gimple_purge_dead_eh_edges below. */
6921 free_dominance_info (CDI_DOMINATORS);
6927 /* Removes edge E and all the blocks dominated by it, and updates dominance
6928 information. The IL in E->src needs to be updated separately.
6929 If dominance info is not available, only the edge E is removed.*/
6932 remove_edge_and_dominated_blocks (edge e)
6934 VEC (basic_block, heap) *bbs_to_remove = NULL;
6935 VEC (basic_block, heap) *bbs_to_fix_dom = NULL;
6939 bool none_removed = false;
6941 basic_block bb, dbb;
6944 if (!dom_info_available_p (CDI_DOMINATORS))
6950 /* No updating is needed for edges to exit. */
6951 if (e->dest == EXIT_BLOCK_PTR)
6953 if (cfgcleanup_altered_bbs)
6954 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
6959 /* First, we find the basic blocks to remove. If E->dest has a predecessor
6960 that is not dominated by E->dest, then this set is empty. Otherwise,
6961 all the basic blocks dominated by E->dest are removed.
6963 Also, to DF_IDOM we store the immediate dominators of the blocks in
6964 the dominance frontier of E (i.e., of the successors of the
6965 removed blocks, if there are any, and of E->dest otherwise). */
6966 FOR_EACH_EDGE (f, ei, e->dest->preds)
6971 if (!dominated_by_p (CDI_DOMINATORS, f->src, e->dest))
6973 none_removed = true;
6978 df = BITMAP_ALLOC (NULL);
6979 df_idom = BITMAP_ALLOC (NULL);
6982 bitmap_set_bit (df_idom,
6983 get_immediate_dominator (CDI_DOMINATORS, e->dest)->index);
6986 bbs_to_remove = get_all_dominated_blocks (CDI_DOMINATORS, e->dest);
6987 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6989 FOR_EACH_EDGE (f, ei, bb->succs)
6991 if (f->dest != EXIT_BLOCK_PTR)
6992 bitmap_set_bit (df, f->dest->index);
6995 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
6996 bitmap_clear_bit (df, bb->index);
6998 EXECUTE_IF_SET_IN_BITMAP (df, 0, i, bi)
7000 bb = BASIC_BLOCK (i);
7001 bitmap_set_bit (df_idom,
7002 get_immediate_dominator (CDI_DOMINATORS, bb)->index);
7006 if (cfgcleanup_altered_bbs)
7008 /* Record the set of the altered basic blocks. */
7009 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
7010 bitmap_ior_into (cfgcleanup_altered_bbs, df);
7013 /* Remove E and the cancelled blocks. */
7018 /* Walk backwards so as to get a chance to substitute all
7019 released DEFs into debug stmts. See
7020 eliminate_unnecessary_stmts() in tree-ssa-dce.c for more
7022 for (i = VEC_length (basic_block, bbs_to_remove); i-- > 0; )
7023 delete_basic_block (VEC_index (basic_block, bbs_to_remove, i));
7026 /* Update the dominance information. The immediate dominator may change only
7027 for blocks whose immediate dominator belongs to DF_IDOM:
7029 Suppose that idom(X) = Y before removal of E and idom(X) != Y after the
7030 removal. Let Z the arbitrary block such that idom(Z) = Y and
7031 Z dominates X after the removal. Before removal, there exists a path P
7032 from Y to X that avoids Z. Let F be the last edge on P that is
7033 removed, and let W = F->dest. Before removal, idom(W) = Y (since Y
7034 dominates W, and because of P, Z does not dominate W), and W belongs to
7035 the dominance frontier of E. Therefore, Y belongs to DF_IDOM. */
7036 EXECUTE_IF_SET_IN_BITMAP (df_idom, 0, i, bi)
7038 bb = BASIC_BLOCK (i);
7039 for (dbb = first_dom_son (CDI_DOMINATORS, bb);
7041 dbb = next_dom_son (CDI_DOMINATORS, dbb))
7042 VEC_safe_push (basic_block, heap, bbs_to_fix_dom, dbb);
7045 iterate_fix_dominators (CDI_DOMINATORS, bbs_to_fix_dom, true);
7048 BITMAP_FREE (df_idom);
7049 VEC_free (basic_block, heap, bbs_to_remove);
7050 VEC_free (basic_block, heap, bbs_to_fix_dom);
7053 /* Purge dead EH edges from basic block BB. */
7056 gimple_purge_dead_eh_edges (basic_block bb)
7058 bool changed = false;
7061 gimple stmt = last_stmt (bb);
7063 if (stmt && stmt_can_throw_internal (stmt))
7066 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
7068 if (e->flags & EDGE_EH)
7070 remove_edge_and_dominated_blocks (e);
7081 gimple_purge_all_dead_eh_edges (const_bitmap blocks)
7083 bool changed = false;
7087 EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
7089 basic_block bb = BASIC_BLOCK (i);
7091 /* Earlier gimple_purge_dead_eh_edges could have removed
7092 this basic block already. */
7093 gcc_assert (bb || changed);
7095 changed |= gimple_purge_dead_eh_edges (bb);
7101 /* This function is called whenever a new edge is created or
7105 gimple_execute_on_growing_pred (edge e)
7107 basic_block bb = e->dest;
7110 reserve_phi_args_for_new_edge (bb);
7113 /* This function is called immediately before edge E is removed from
7114 the edge vector E->dest->preds. */
7117 gimple_execute_on_shrinking_pred (edge e)
7119 if (phi_nodes (e->dest))
7120 remove_phi_args (e);
7123 /*---------------------------------------------------------------------------
7124 Helper functions for Loop versioning
7125 ---------------------------------------------------------------------------*/
7127 /* Adjust phi nodes for 'first' basic block. 'second' basic block is a copy
7128 of 'first'. Both of them are dominated by 'new_head' basic block. When
7129 'new_head' was created by 'second's incoming edge it received phi arguments
7130 on the edge by split_edge(). Later, additional edge 'e' was created to
7131 connect 'new_head' and 'first'. Now this routine adds phi args on this
7132 additional edge 'e' that new_head to second edge received as part of edge
7136 gimple_lv_adjust_loop_header_phi (basic_block first, basic_block second,
7137 basic_block new_head, edge e)
7140 gimple_stmt_iterator psi1, psi2;
7142 edge e2 = find_edge (new_head, second);
7144 /* Because NEW_HEAD has been created by splitting SECOND's incoming
7145 edge, we should always have an edge from NEW_HEAD to SECOND. */
7146 gcc_assert (e2 != NULL);
7148 /* Browse all 'second' basic block phi nodes and add phi args to
7149 edge 'e' for 'first' head. PHI args are always in correct order. */
7151 for (psi2 = gsi_start_phis (second),
7152 psi1 = gsi_start_phis (first);
7153 !gsi_end_p (psi2) && !gsi_end_p (psi1);
7154 gsi_next (&psi2), gsi_next (&psi1))
7156 phi1 = gsi_stmt (psi1);
7157 phi2 = gsi_stmt (psi2);
7158 def = PHI_ARG_DEF (phi2, e2->dest_idx);
7159 add_phi_arg (phi1, def, e, gimple_phi_arg_location_from_edge (phi2, e2));
7164 /* Adds a if else statement to COND_BB with condition COND_EXPR.
7165 SECOND_HEAD is the destination of the THEN and FIRST_HEAD is
7166 the destination of the ELSE part. */
7169 gimple_lv_add_condition_to_bb (basic_block first_head ATTRIBUTE_UNUSED,
7170 basic_block second_head ATTRIBUTE_UNUSED,
7171 basic_block cond_bb, void *cond_e)
7173 gimple_stmt_iterator gsi;
7174 gimple new_cond_expr;
7175 tree cond_expr = (tree) cond_e;
7178 /* Build new conditional expr */
7179 new_cond_expr = gimple_build_cond_from_tree (cond_expr,
7180 NULL_TREE, NULL_TREE);
7182 /* Add new cond in cond_bb. */
7183 gsi = gsi_last_bb (cond_bb);
7184 gsi_insert_after (&gsi, new_cond_expr, GSI_NEW_STMT);
7186 /* Adjust edges appropriately to connect new head with first head
7187 as well as second head. */
7188 e0 = single_succ_edge (cond_bb);
7189 e0->flags &= ~EDGE_FALLTHRU;
7190 e0->flags |= EDGE_FALSE_VALUE;
7193 struct cfg_hooks gimple_cfg_hooks = {
7195 gimple_verify_flow_info,
7196 gimple_dump_bb, /* dump_bb */
7197 create_bb, /* create_basic_block */
7198 gimple_redirect_edge_and_branch, /* redirect_edge_and_branch */
7199 gimple_redirect_edge_and_branch_force, /* redirect_edge_and_branch_force */
7200 gimple_can_remove_branch_p, /* can_remove_branch_p */
7201 remove_bb, /* delete_basic_block */
7202 gimple_split_block, /* split_block */
7203 gimple_move_block_after, /* move_block_after */
7204 gimple_can_merge_blocks_p, /* can_merge_blocks_p */
7205 gimple_merge_blocks, /* merge_blocks */
7206 gimple_predict_edge, /* predict_edge */
7207 gimple_predicted_by_p, /* predicted_by_p */
7208 gimple_can_duplicate_bb_p, /* can_duplicate_block_p */
7209 gimple_duplicate_bb, /* duplicate_block */
7210 gimple_split_edge, /* split_edge */
7211 gimple_make_forwarder_block, /* make_forward_block */
7212 NULL, /* tidy_fallthru_edge */
7213 gimple_block_ends_with_call_p,/* block_ends_with_call_p */
7214 gimple_block_ends_with_condjump_p, /* block_ends_with_condjump_p */
7215 gimple_flow_call_edges_add, /* flow_call_edges_add */
7216 gimple_execute_on_growing_pred, /* execute_on_growing_pred */
7217 gimple_execute_on_shrinking_pred, /* execute_on_shrinking_pred */
7218 gimple_duplicate_loop_to_header_edge, /* duplicate loop for trees */
7219 gimple_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
7220 gimple_lv_adjust_loop_header_phi, /* lv_adjust_loop_header_phi*/
7221 extract_true_false_edges_from_block, /* extract_cond_bb_edges */
7222 flush_pending_stmts /* flush_pending_stmts */
7226 /* Split all critical edges. */
7229 split_critical_edges (void)
7235 /* split_edge can redirect edges out of SWITCH_EXPRs, which can get
7236 expensive. So we want to enable recording of edge to CASE_LABEL_EXPR
7237 mappings around the calls to split_edge. */
7238 start_recording_case_labels ();
7241 FOR_EACH_EDGE (e, ei, bb->succs)
7243 if (EDGE_CRITICAL_P (e) && !(e->flags & EDGE_ABNORMAL))
7245 /* PRE inserts statements to edges and expects that
7246 since split_critical_edges was done beforehand, committing edge
7247 insertions will not split more edges. In addition to critical
7248 edges we must split edges that have multiple successors and
7249 end by control flow statements, such as RESX.
7250 Go ahead and split them too. This matches the logic in
7251 gimple_find_edge_insert_loc. */
7252 else if ((!single_pred_p (e->dest)
7253 || phi_nodes (e->dest)
7254 || e->dest == EXIT_BLOCK_PTR)
7255 && e->src != ENTRY_BLOCK_PTR
7256 && !(e->flags & EDGE_ABNORMAL))
7258 gimple_stmt_iterator gsi;
7260 gsi = gsi_last_bb (e->src);
7261 if (!gsi_end_p (gsi)
7262 && stmt_ends_bb_p (gsi_stmt (gsi))
7263 && gimple_code (gsi_stmt (gsi)) != GIMPLE_RETURN)
7268 end_recording_case_labels ();
7272 struct gimple_opt_pass pass_split_crit_edges =
7276 "crited", /* name */
7278 split_critical_edges, /* execute */
7281 0, /* static_pass_number */
7282 TV_TREE_SPLIT_EDGES, /* tv_id */
7283 PROP_cfg, /* properties required */
7284 PROP_no_crit_edges, /* properties_provided */
7285 0, /* properties_destroyed */
7286 0, /* todo_flags_start */
7287 TODO_dump_func | TODO_verify_flow /* todo_flags_finish */
7292 /* Build a ternary operation and gimplify it. Emit code before GSI.
7293 Return the gimple_val holding the result. */
7296 gimplify_build3 (gimple_stmt_iterator *gsi, enum tree_code code,
7297 tree type, tree a, tree b, tree c)
7300 location_t loc = gimple_location (gsi_stmt (*gsi));
7302 ret = fold_build3_loc (loc, code, type, a, b, c);
7305 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7309 /* Build a binary operation and gimplify it. Emit code before GSI.
7310 Return the gimple_val holding the result. */
7313 gimplify_build2 (gimple_stmt_iterator *gsi, enum tree_code code,
7314 tree type, tree a, tree b)
7318 ret = fold_build2_loc (gimple_location (gsi_stmt (*gsi)), code, type, a, b);
7321 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7325 /* Build a unary operation and gimplify it. Emit code before GSI.
7326 Return the gimple_val holding the result. */
7329 gimplify_build1 (gimple_stmt_iterator *gsi, enum tree_code code, tree type,
7334 ret = fold_build1_loc (gimple_location (gsi_stmt (*gsi)), code, type, a);
7337 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7343 /* Emit return warnings. */
7346 execute_warn_function_return (void)
7348 source_location location;
7353 /* If we have a path to EXIT, then we do return. */
7354 if (TREE_THIS_VOLATILE (cfun->decl)
7355 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0)
7357 location = UNKNOWN_LOCATION;
7358 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7360 last = last_stmt (e->src);
7361 if (gimple_code (last) == GIMPLE_RETURN
7362 && (location = gimple_location (last)) != UNKNOWN_LOCATION)
7365 if (location == UNKNOWN_LOCATION)
7366 location = cfun->function_end_locus;
7367 warning_at (location, 0, "%<noreturn%> function does return");
7370 /* If we see "return;" in some basic block, then we do reach the end
7371 without returning a value. */
7372 else if (warn_return_type
7373 && !TREE_NO_WARNING (cfun->decl)
7374 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0
7375 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (cfun->decl))))
7377 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7379 gimple last = last_stmt (e->src);
7380 if (gimple_code (last) == GIMPLE_RETURN
7381 && gimple_return_retval (last) == NULL
7382 && !gimple_no_warning_p (last))
7384 location = gimple_location (last);
7385 if (location == UNKNOWN_LOCATION)
7386 location = cfun->function_end_locus;
7387 warning_at (location, OPT_Wreturn_type, "control reaches end of non-void function");
7388 TREE_NO_WARNING (cfun->decl) = 1;
7397 /* Given a basic block B which ends with a conditional and has
7398 precisely two successors, determine which of the edges is taken if
7399 the conditional is true and which is taken if the conditional is
7400 false. Set TRUE_EDGE and FALSE_EDGE appropriately. */
7403 extract_true_false_edges_from_block (basic_block b,
7407 edge e = EDGE_SUCC (b, 0);
7409 if (e->flags & EDGE_TRUE_VALUE)
7412 *false_edge = EDGE_SUCC (b, 1);
7417 *true_edge = EDGE_SUCC (b, 1);
7421 struct gimple_opt_pass pass_warn_function_return =
7427 execute_warn_function_return, /* execute */
7430 0, /* static_pass_number */
7431 TV_NONE, /* tv_id */
7432 PROP_cfg, /* properties_required */
7433 0, /* properties_provided */
7434 0, /* properties_destroyed */
7435 0, /* todo_flags_start */
7436 0 /* todo_flags_finish */
7440 /* Emit noreturn warnings. */
7443 execute_warn_function_noreturn (void)
7445 if (warn_missing_noreturn
7446 && !TREE_THIS_VOLATILE (cfun->decl)
7447 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0
7448 && !lang_hooks.missing_noreturn_ok_p (cfun->decl))
7449 warning_at (DECL_SOURCE_LOCATION (cfun->decl), OPT_Wmissing_noreturn,
7450 "function might be possible candidate "
7451 "for attribute %<noreturn%>");
7455 struct gimple_opt_pass pass_warn_function_noreturn =
7461 execute_warn_function_noreturn, /* execute */
7464 0, /* static_pass_number */
7465 TV_NONE, /* tv_id */
7466 PROP_cfg, /* properties_required */
7467 0, /* properties_provided */
7468 0, /* properties_destroyed */
7469 0, /* todo_flags_start */
7470 0 /* todo_flags_finish */
7475 /* Walk a gimplified function and warn for functions whose return value is
7476 ignored and attribute((warn_unused_result)) is set. This is done before
7477 inlining, so we don't have to worry about that. */
7480 do_warn_unused_result (gimple_seq seq)
7483 gimple_stmt_iterator i;
7485 for (i = gsi_start (seq); !gsi_end_p (i); gsi_next (&i))
7487 gimple g = gsi_stmt (i);
7489 switch (gimple_code (g))
7492 do_warn_unused_result (gimple_bind_body (g));
7495 do_warn_unused_result (gimple_try_eval (g));
7496 do_warn_unused_result (gimple_try_cleanup (g));
7499 do_warn_unused_result (gimple_catch_handler (g));
7501 case GIMPLE_EH_FILTER:
7502 do_warn_unused_result (gimple_eh_filter_failure (g));
7506 if (gimple_call_lhs (g))
7509 /* This is a naked call, as opposed to a GIMPLE_CALL with an
7510 LHS. All calls whose value is ignored should be
7511 represented like this. Look for the attribute. */
7512 fdecl = gimple_call_fndecl (g);
7513 ftype = TREE_TYPE (TREE_TYPE (gimple_call_fn (g)));
7515 if (lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (ftype)))
7517 location_t loc = gimple_location (g);
7520 warning_at (loc, OPT_Wunused_result,
7521 "ignoring return value of %qD, "
7522 "declared with attribute warn_unused_result",
7525 warning_at (loc, OPT_Wunused_result,
7526 "ignoring return value of function "
7527 "declared with attribute warn_unused_result");
7532 /* Not a container, not a call, or a call whose value is used. */
7539 run_warn_unused_result (void)
7541 do_warn_unused_result (gimple_body (current_function_decl));
7546 gate_warn_unused_result (void)
7548 return flag_warn_unused_result;
7551 struct gimple_opt_pass pass_warn_unused_result =
7555 "*warn_unused_result", /* name */
7556 gate_warn_unused_result, /* gate */
7557 run_warn_unused_result, /* execute */
7560 0, /* static_pass_number */
7561 TV_NONE, /* tv_id */
7562 PROP_gimple_any, /* properties_required */
7563 0, /* properties_provided */
7564 0, /* properties_destroyed */
7565 0, /* todo_flags_start */
7566 0, /* todo_flags_finish */