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 void make_gimple_asm_edges (basic_block);
103 static unsigned int locus_map_hash (const void *);
104 static int locus_map_eq (const void *, const void *);
105 static void assign_discriminator (location_t, basic_block);
106 static edge gimple_redirect_edge_and_branch (edge, basic_block);
107 static edge gimple_try_redirect_by_replacing_jump (edge, basic_block);
108 static unsigned int split_critical_edges (void);
110 /* Various helpers. */
111 static inline bool stmt_starts_bb_p (gimple, gimple);
112 static int gimple_verify_flow_info (void);
113 static void gimple_make_forwarder_block (edge);
114 static void gimple_cfg2vcg (FILE *);
115 static gimple first_non_label_stmt (basic_block);
117 /* Flowgraph optimization and cleanup. */
118 static void gimple_merge_blocks (basic_block, basic_block);
119 static bool gimple_can_merge_blocks_p (basic_block, basic_block);
120 static void remove_bb (basic_block);
121 static edge find_taken_edge_computed_goto (basic_block, tree);
122 static edge find_taken_edge_cond_expr (basic_block, tree);
123 static edge find_taken_edge_switch_expr (basic_block, tree);
124 static tree find_case_label_for_value (gimple, tree);
127 init_empty_tree_cfg_for_function (struct function *fn)
129 /* Initialize the basic block array. */
131 profile_status_for_function (fn) = PROFILE_ABSENT;
132 n_basic_blocks_for_function (fn) = NUM_FIXED_BLOCKS;
133 last_basic_block_for_function (fn) = NUM_FIXED_BLOCKS;
134 basic_block_info_for_function (fn)
135 = VEC_alloc (basic_block, gc, initial_cfg_capacity);
136 VEC_safe_grow_cleared (basic_block, gc,
137 basic_block_info_for_function (fn),
138 initial_cfg_capacity);
140 /* Build a mapping of labels to their associated blocks. */
141 label_to_block_map_for_function (fn)
142 = VEC_alloc (basic_block, gc, initial_cfg_capacity);
143 VEC_safe_grow_cleared (basic_block, gc,
144 label_to_block_map_for_function (fn),
145 initial_cfg_capacity);
147 SET_BASIC_BLOCK_FOR_FUNCTION (fn, ENTRY_BLOCK,
148 ENTRY_BLOCK_PTR_FOR_FUNCTION (fn));
149 SET_BASIC_BLOCK_FOR_FUNCTION (fn, EXIT_BLOCK,
150 EXIT_BLOCK_PTR_FOR_FUNCTION (fn));
152 ENTRY_BLOCK_PTR_FOR_FUNCTION (fn)->next_bb
153 = EXIT_BLOCK_PTR_FOR_FUNCTION (fn);
154 EXIT_BLOCK_PTR_FOR_FUNCTION (fn)->prev_bb
155 = ENTRY_BLOCK_PTR_FOR_FUNCTION (fn);
159 init_empty_tree_cfg (void)
161 init_empty_tree_cfg_for_function (cfun);
164 /*---------------------------------------------------------------------------
166 ---------------------------------------------------------------------------*/
168 /* Entry point to the CFG builder for trees. SEQ is the sequence of
169 statements to be added to the flowgraph. */
172 build_gimple_cfg (gimple_seq seq)
174 /* Register specific gimple functions. */
175 gimple_register_cfg_hooks ();
177 memset ((void *) &cfg_stats, 0, sizeof (cfg_stats));
179 init_empty_tree_cfg ();
181 found_computed_goto = 0;
184 /* Computed gotos are hell to deal with, especially if there are
185 lots of them with a large number of destinations. So we factor
186 them to a common computed goto location before we build the
187 edge list. After we convert back to normal form, we will un-factor
188 the computed gotos since factoring introduces an unwanted jump. */
189 if (found_computed_goto)
190 factor_computed_gotos ();
192 /* Make sure there is always at least one block, even if it's empty. */
193 if (n_basic_blocks == NUM_FIXED_BLOCKS)
194 create_empty_bb (ENTRY_BLOCK_PTR);
196 /* Adjust the size of the array. */
197 if (VEC_length (basic_block, basic_block_info) < (size_t) n_basic_blocks)
198 VEC_safe_grow_cleared (basic_block, gc, basic_block_info, n_basic_blocks);
200 /* To speed up statement iterator walks, we first purge dead labels. */
201 cleanup_dead_labels ();
203 /* Group case nodes to reduce the number of edges.
204 We do this after cleaning up dead labels because otherwise we miss
205 a lot of obvious case merging opportunities. */
206 group_case_labels ();
208 /* Create the edges of the flowgraph. */
209 discriminator_per_locus = htab_create (13, locus_map_hash, locus_map_eq,
212 cleanup_dead_labels ();
213 htab_delete (discriminator_per_locus);
215 /* Debugging dumps. */
217 /* Write the flowgraph to a VCG file. */
219 int local_dump_flags;
220 FILE *vcg_file = dump_begin (TDI_vcg, &local_dump_flags);
223 gimple_cfg2vcg (vcg_file);
224 dump_end (TDI_vcg, vcg_file);
228 #ifdef ENABLE_CHECKING
234 execute_build_cfg (void)
236 gimple_seq body = gimple_body (current_function_decl);
238 build_gimple_cfg (body);
239 gimple_set_body (current_function_decl, NULL);
240 if (dump_file && (dump_flags & TDF_DETAILS))
242 fprintf (dump_file, "Scope blocks:\n");
243 dump_scope_blocks (dump_file, dump_flags);
248 struct gimple_opt_pass pass_build_cfg =
254 execute_build_cfg, /* execute */
257 0, /* static_pass_number */
258 TV_TREE_CFG, /* tv_id */
259 PROP_gimple_leh, /* properties_required */
260 PROP_cfg, /* properties_provided */
261 0, /* properties_destroyed */
262 0, /* todo_flags_start */
263 TODO_verify_stmts | TODO_cleanup_cfg
264 | TODO_dump_func /* todo_flags_finish */
269 /* Return true if T is a computed goto. */
272 computed_goto_p (gimple t)
274 return (gimple_code (t) == GIMPLE_GOTO
275 && TREE_CODE (gimple_goto_dest (t)) != LABEL_DECL);
279 /* Search the CFG for any computed gotos. If found, factor them to a
280 common computed goto site. Also record the location of that site so
281 that we can un-factor the gotos after we have converted back to
285 factor_computed_gotos (void)
288 tree factored_label_decl = NULL;
290 gimple factored_computed_goto_label = NULL;
291 gimple factored_computed_goto = NULL;
293 /* We know there are one or more computed gotos in this function.
294 Examine the last statement in each basic block to see if the block
295 ends with a computed goto. */
299 gimple_stmt_iterator gsi = gsi_last_bb (bb);
305 last = gsi_stmt (gsi);
307 /* Ignore the computed goto we create when we factor the original
309 if (last == factored_computed_goto)
312 /* If the last statement is a computed goto, factor it. */
313 if (computed_goto_p (last))
317 /* The first time we find a computed goto we need to create
318 the factored goto block and the variable each original
319 computed goto will use for their goto destination. */
320 if (!factored_computed_goto)
322 basic_block new_bb = create_empty_bb (bb);
323 gimple_stmt_iterator new_gsi = gsi_start_bb (new_bb);
325 /* Create the destination of the factored goto. Each original
326 computed goto will put its desired destination into this
327 variable and jump to the label we create immediately
329 var = create_tmp_var (ptr_type_node, "gotovar");
331 /* Build a label for the new block which will contain the
332 factored computed goto. */
333 factored_label_decl = create_artificial_label (UNKNOWN_LOCATION);
334 factored_computed_goto_label
335 = gimple_build_label (factored_label_decl);
336 gsi_insert_after (&new_gsi, factored_computed_goto_label,
339 /* Build our new computed goto. */
340 factored_computed_goto = gimple_build_goto (var);
341 gsi_insert_after (&new_gsi, factored_computed_goto, GSI_NEW_STMT);
344 /* Copy the original computed goto's destination into VAR. */
345 assignment = gimple_build_assign (var, gimple_goto_dest (last));
346 gsi_insert_before (&gsi, assignment, GSI_SAME_STMT);
348 /* And re-vector the computed goto to the new destination. */
349 gimple_goto_set_dest (last, factored_label_decl);
355 /* Build a flowgraph for the sequence of stmts SEQ. */
358 make_blocks (gimple_seq seq)
360 gimple_stmt_iterator i = gsi_start (seq);
362 bool start_new_block = true;
363 bool first_stmt_of_seq = true;
364 basic_block bb = ENTRY_BLOCK_PTR;
366 while (!gsi_end_p (i))
373 /* If the statement starts a new basic block or if we have determined
374 in a previous pass that we need to create a new block for STMT, do
376 if (start_new_block || stmt_starts_bb_p (stmt, prev_stmt))
378 if (!first_stmt_of_seq)
379 seq = gsi_split_seq_before (&i);
380 bb = create_basic_block (seq, NULL, bb);
381 start_new_block = false;
384 /* Now add STMT to BB and create the subgraphs for special statement
386 gimple_set_bb (stmt, bb);
388 if (computed_goto_p (stmt))
389 found_computed_goto = true;
391 /* If STMT is a basic block terminator, set START_NEW_BLOCK for the
393 if (stmt_ends_bb_p (stmt))
395 /* If the stmt can make abnormal goto use a new temporary
396 for the assignment to the LHS. This makes sure the old value
397 of the LHS is available on the abnormal edge. Otherwise
398 we will end up with overlapping life-ranges for abnormal
400 if (gimple_has_lhs (stmt)
401 && stmt_can_make_abnormal_goto (stmt)
402 && is_gimple_reg_type (TREE_TYPE (gimple_get_lhs (stmt))))
404 tree lhs = gimple_get_lhs (stmt);
405 tree tmp = create_tmp_var (TREE_TYPE (lhs), NULL);
406 gimple s = gimple_build_assign (lhs, tmp);
407 gimple_set_location (s, gimple_location (stmt));
408 gimple_set_block (s, gimple_block (stmt));
409 gimple_set_lhs (stmt, tmp);
410 if (TREE_CODE (TREE_TYPE (tmp)) == COMPLEX_TYPE
411 || TREE_CODE (TREE_TYPE (tmp)) == VECTOR_TYPE)
412 DECL_GIMPLE_REG_P (tmp) = 1;
413 gsi_insert_after (&i, s, GSI_SAME_STMT);
415 start_new_block = true;
419 first_stmt_of_seq = false;
424 /* Create and return a new empty basic block after bb AFTER. */
427 create_bb (void *h, void *e, basic_block after)
433 /* Create and initialize a new basic block. Since alloc_block uses
434 ggc_alloc_cleared to allocate a basic block, we do not have to
435 clear the newly allocated basic block here. */
438 bb->index = last_basic_block;
440 bb->il.gimple = GGC_CNEW (struct gimple_bb_info);
441 set_bb_seq (bb, h ? (gimple_seq) h : gimple_seq_alloc ());
443 /* Add the new block to the linked list of blocks. */
444 link_block (bb, after);
446 /* Grow the basic block array if needed. */
447 if ((size_t) last_basic_block == VEC_length (basic_block, basic_block_info))
449 size_t new_size = last_basic_block + (last_basic_block + 3) / 4;
450 VEC_safe_grow_cleared (basic_block, gc, basic_block_info, new_size);
453 /* Add the newly created block to the array. */
454 SET_BASIC_BLOCK (last_basic_block, bb);
463 /*---------------------------------------------------------------------------
465 ---------------------------------------------------------------------------*/
467 /* Fold COND_EXPR_COND of each COND_EXPR. */
470 fold_cond_expr_cond (void)
476 gimple stmt = last_stmt (bb);
478 if (stmt && gimple_code (stmt) == GIMPLE_COND)
480 location_t loc = gimple_location (stmt);
484 fold_defer_overflow_warnings ();
485 cond = fold_binary_loc (loc, gimple_cond_code (stmt), boolean_type_node,
486 gimple_cond_lhs (stmt), gimple_cond_rhs (stmt));
489 zerop = integer_zerop (cond);
490 onep = integer_onep (cond);
493 zerop = onep = false;
495 fold_undefer_overflow_warnings (zerop || onep,
497 WARN_STRICT_OVERFLOW_CONDITIONAL);
499 gimple_cond_make_false (stmt);
501 gimple_cond_make_true (stmt);
506 /* Join all the blocks in the flowgraph. */
512 struct omp_region *cur_region = NULL;
514 /* Create an edge from entry to the first block with executable
516 make_edge (ENTRY_BLOCK_PTR, BASIC_BLOCK (NUM_FIXED_BLOCKS), EDGE_FALLTHRU);
518 /* Traverse the basic block array placing edges. */
521 gimple last = last_stmt (bb);
526 enum gimple_code code = gimple_code (last);
530 make_goto_expr_edges (bb);
534 make_edge (bb, EXIT_BLOCK_PTR, 0);
538 make_cond_expr_edges (bb);
542 make_gimple_switch_edges (bb);
546 make_eh_edges (last);
549 case GIMPLE_EH_DISPATCH:
550 fallthru = make_eh_dispatch_edges (last);
554 /* If this function receives a nonlocal goto, then we need to
555 make edges from this call site to all the nonlocal goto
557 if (stmt_can_make_abnormal_goto (last))
558 make_abnormal_goto_edges (bb, true);
560 /* If this statement has reachable exception handlers, then
561 create abnormal edges to them. */
562 make_eh_edges (last);
564 /* Some calls are known not to return. */
565 fallthru = !(gimple_call_flags (last) & ECF_NORETURN);
569 /* A GIMPLE_ASSIGN may throw internally and thus be considered
571 if (is_ctrl_altering_stmt (last))
572 make_eh_edges (last);
577 make_gimple_asm_edges (bb);
581 case GIMPLE_OMP_PARALLEL:
582 case GIMPLE_OMP_TASK:
584 case GIMPLE_OMP_SINGLE:
585 case GIMPLE_OMP_MASTER:
586 case GIMPLE_OMP_ORDERED:
587 case GIMPLE_OMP_CRITICAL:
588 case GIMPLE_OMP_SECTION:
589 cur_region = new_omp_region (bb, code, cur_region);
593 case GIMPLE_OMP_SECTIONS:
594 cur_region = new_omp_region (bb, code, cur_region);
598 case GIMPLE_OMP_SECTIONS_SWITCH:
602 case GIMPLE_OMP_ATOMIC_LOAD:
603 case GIMPLE_OMP_ATOMIC_STORE:
607 case GIMPLE_OMP_RETURN:
608 /* In the case of a GIMPLE_OMP_SECTION, the edge will go
609 somewhere other than the next block. This will be
611 cur_region->exit = bb;
612 fallthru = cur_region->type != GIMPLE_OMP_SECTION;
613 cur_region = cur_region->outer;
616 case GIMPLE_OMP_CONTINUE:
617 cur_region->cont = bb;
618 switch (cur_region->type)
621 /* Mark all GIMPLE_OMP_FOR and GIMPLE_OMP_CONTINUE
622 succs edges as abnormal to prevent splitting
624 single_succ_edge (cur_region->entry)->flags |= EDGE_ABNORMAL;
625 /* Make the loopback edge. */
626 make_edge (bb, single_succ (cur_region->entry),
629 /* Create an edge from GIMPLE_OMP_FOR to exit, which
630 corresponds to the case that the body of the loop
631 is not executed at all. */
632 make_edge (cur_region->entry, bb->next_bb, EDGE_ABNORMAL);
633 make_edge (bb, bb->next_bb, EDGE_FALLTHRU | EDGE_ABNORMAL);
637 case GIMPLE_OMP_SECTIONS:
638 /* Wire up the edges into and out of the nested sections. */
640 basic_block switch_bb = single_succ (cur_region->entry);
642 struct omp_region *i;
643 for (i = cur_region->inner; i ; i = i->next)
645 gcc_assert (i->type == GIMPLE_OMP_SECTION);
646 make_edge (switch_bb, i->entry, 0);
647 make_edge (i->exit, bb, EDGE_FALLTHRU);
650 /* Make the loopback edge to the block with
651 GIMPLE_OMP_SECTIONS_SWITCH. */
652 make_edge (bb, switch_bb, 0);
654 /* Make the edge from the switch to exit. */
655 make_edge (switch_bb, bb->next_bb, 0);
666 gcc_assert (!stmt_ends_bb_p (last));
675 make_edge (bb, bb->next_bb, EDGE_FALLTHRU);
677 assign_discriminator (gimple_location (last), bb->next_bb);
684 /* Fold COND_EXPR_COND of each COND_EXPR. */
685 fold_cond_expr_cond ();
688 /* Trivial hash function for a location_t. ITEM is a pointer to
689 a hash table entry that maps a location_t to a discriminator. */
692 locus_map_hash (const void *item)
694 return ((const struct locus_discrim_map *) item)->locus;
697 /* Equality function for the locus-to-discriminator map. VA and VB
698 point to the two hash table entries to compare. */
701 locus_map_eq (const void *va, const void *vb)
703 const struct locus_discrim_map *a = (const struct locus_discrim_map *) va;
704 const struct locus_discrim_map *b = (const struct locus_discrim_map *) vb;
705 return a->locus == b->locus;
708 /* Find the next available discriminator value for LOCUS. The
709 discriminator distinguishes among several basic blocks that
710 share a common locus, allowing for more accurate sample-based
714 next_discriminator_for_locus (location_t locus)
716 struct locus_discrim_map item;
717 struct locus_discrim_map **slot;
720 item.discriminator = 0;
721 slot = (struct locus_discrim_map **)
722 htab_find_slot_with_hash (discriminator_per_locus, (void *) &item,
723 (hashval_t) locus, INSERT);
725 if (*slot == HTAB_EMPTY_ENTRY)
727 *slot = XNEW (struct locus_discrim_map);
729 (*slot)->locus = locus;
730 (*slot)->discriminator = 0;
732 (*slot)->discriminator++;
733 return (*slot)->discriminator;
736 /* Return TRUE if LOCUS1 and LOCUS2 refer to the same source line. */
739 same_line_p (location_t locus1, location_t locus2)
741 expanded_location from, to;
743 if (locus1 == locus2)
746 from = expand_location (locus1);
747 to = expand_location (locus2);
749 if (from.line != to.line)
751 if (from.file == to.file)
753 return (from.file != NULL
755 && strcmp (from.file, to.file) == 0);
758 /* Assign a unique discriminator value to block BB if it begins at the same
759 LOCUS as its predecessor block. */
762 assign_discriminator (location_t locus, basic_block bb)
764 gimple first_in_to_bb, last_in_to_bb;
766 if (locus == 0 || bb->discriminator != 0)
769 first_in_to_bb = first_non_label_stmt (bb);
770 last_in_to_bb = last_stmt (bb);
771 if ((first_in_to_bb && same_line_p (locus, gimple_location (first_in_to_bb)))
772 || (last_in_to_bb && same_line_p (locus, gimple_location (last_in_to_bb))))
773 bb->discriminator = next_discriminator_for_locus (locus);
776 /* Create the edges for a GIMPLE_COND starting at block BB. */
779 make_cond_expr_edges (basic_block bb)
781 gimple entry = last_stmt (bb);
782 gimple then_stmt, else_stmt;
783 basic_block then_bb, else_bb;
784 tree then_label, else_label;
786 location_t entry_locus;
789 gcc_assert (gimple_code (entry) == GIMPLE_COND);
791 entry_locus = gimple_location (entry);
793 /* Entry basic blocks for each component. */
794 then_label = gimple_cond_true_label (entry);
795 else_label = gimple_cond_false_label (entry);
796 then_bb = label_to_block (then_label);
797 else_bb = label_to_block (else_label);
798 then_stmt = first_stmt (then_bb);
799 else_stmt = first_stmt (else_bb);
801 e = make_edge (bb, then_bb, EDGE_TRUE_VALUE);
802 assign_discriminator (entry_locus, then_bb);
803 e->goto_locus = gimple_location (then_stmt);
805 e->goto_block = gimple_block (then_stmt);
806 e = make_edge (bb, else_bb, EDGE_FALSE_VALUE);
809 assign_discriminator (entry_locus, else_bb);
810 e->goto_locus = gimple_location (else_stmt);
812 e->goto_block = gimple_block (else_stmt);
815 /* We do not need the labels anymore. */
816 gimple_cond_set_true_label (entry, NULL_TREE);
817 gimple_cond_set_false_label (entry, NULL_TREE);
821 /* Called for each element in the hash table (P) as we delete the
822 edge to cases hash table.
824 Clear all the TREE_CHAINs to prevent problems with copying of
825 SWITCH_EXPRs and structure sharing rules, then free the hash table
829 edge_to_cases_cleanup (const void *key ATTRIBUTE_UNUSED, void **value,
830 void *data ATTRIBUTE_UNUSED)
834 for (t = (tree) *value; t; t = next)
836 next = TREE_CHAIN (t);
837 TREE_CHAIN (t) = NULL;
844 /* Start recording information mapping edges to case labels. */
847 start_recording_case_labels (void)
849 gcc_assert (edge_to_cases == NULL);
850 edge_to_cases = pointer_map_create ();
853 /* Return nonzero if we are recording information for case labels. */
856 recording_case_labels_p (void)
858 return (edge_to_cases != NULL);
861 /* Stop recording information mapping edges to case labels and
862 remove any information we have recorded. */
864 end_recording_case_labels (void)
866 pointer_map_traverse (edge_to_cases, edge_to_cases_cleanup, NULL);
867 pointer_map_destroy (edge_to_cases);
868 edge_to_cases = NULL;
871 /* If we are inside a {start,end}_recording_cases block, then return
872 a chain of CASE_LABEL_EXPRs from T which reference E.
874 Otherwise return NULL. */
877 get_cases_for_edge (edge e, gimple t)
882 /* If we are not recording cases, then we do not have CASE_LABEL_EXPR
883 chains available. Return NULL so the caller can detect this case. */
884 if (!recording_case_labels_p ())
887 slot = pointer_map_contains (edge_to_cases, e);
891 /* If we did not find E in the hash table, then this must be the first
892 time we have been queried for information about E & T. Add all the
893 elements from T to the hash table then perform the query again. */
895 n = gimple_switch_num_labels (t);
896 for (i = 0; i < n; i++)
898 tree elt = gimple_switch_label (t, i);
899 tree lab = CASE_LABEL (elt);
900 basic_block label_bb = label_to_block (lab);
901 edge this_edge = find_edge (e->src, label_bb);
903 /* Add it to the chain of CASE_LABEL_EXPRs referencing E, or create
905 slot = pointer_map_insert (edge_to_cases, this_edge);
906 TREE_CHAIN (elt) = (tree) *slot;
910 return (tree) *pointer_map_contains (edge_to_cases, e);
913 /* Create the edges for a GIMPLE_SWITCH starting at block BB. */
916 make_gimple_switch_edges (basic_block bb)
918 gimple entry = last_stmt (bb);
919 location_t entry_locus;
922 entry_locus = gimple_location (entry);
924 n = gimple_switch_num_labels (entry);
926 for (i = 0; i < n; ++i)
928 tree lab = CASE_LABEL (gimple_switch_label (entry, i));
929 basic_block label_bb = label_to_block (lab);
930 make_edge (bb, label_bb, 0);
931 assign_discriminator (entry_locus, label_bb);
936 /* Return the basic block holding label DEST. */
939 label_to_block_fn (struct function *ifun, tree dest)
941 int uid = LABEL_DECL_UID (dest);
943 /* We would die hard when faced by an undefined label. Emit a label to
944 the very first basic block. This will hopefully make even the dataflow
945 and undefined variable warnings quite right. */
946 if ((errorcount || sorrycount) && uid < 0)
948 gimple_stmt_iterator gsi = gsi_start_bb (BASIC_BLOCK (NUM_FIXED_BLOCKS));
951 stmt = gimple_build_label (dest);
952 gsi_insert_before (&gsi, stmt, GSI_NEW_STMT);
953 uid = LABEL_DECL_UID (dest);
955 if (VEC_length (basic_block, ifun->cfg->x_label_to_block_map)
956 <= (unsigned int) uid)
958 return VEC_index (basic_block, ifun->cfg->x_label_to_block_map, uid);
961 /* Create edges for an abnormal goto statement at block BB. If FOR_CALL
962 is true, the source statement is a CALL_EXPR instead of a GOTO_EXPR. */
965 make_abnormal_goto_edges (basic_block bb, bool for_call)
967 basic_block target_bb;
968 gimple_stmt_iterator gsi;
970 FOR_EACH_BB (target_bb)
971 for (gsi = gsi_start_bb (target_bb); !gsi_end_p (gsi); gsi_next (&gsi))
973 gimple label_stmt = gsi_stmt (gsi);
976 if (gimple_code (label_stmt) != GIMPLE_LABEL)
979 target = gimple_label_label (label_stmt);
981 /* Make an edge to every label block that has been marked as a
982 potential target for a computed goto or a non-local goto. */
983 if ((FORCED_LABEL (target) && !for_call)
984 || (DECL_NONLOCAL (target) && for_call))
986 make_edge (bb, target_bb, EDGE_ABNORMAL);
992 /* Create edges for a goto statement at block BB. */
995 make_goto_expr_edges (basic_block bb)
997 gimple_stmt_iterator last = gsi_last_bb (bb);
998 gimple goto_t = gsi_stmt (last);
1000 /* A simple GOTO creates normal edges. */
1001 if (simple_goto_p (goto_t))
1003 tree dest = gimple_goto_dest (goto_t);
1004 basic_block label_bb = label_to_block (dest);
1005 edge e = make_edge (bb, label_bb, EDGE_FALLTHRU);
1006 e->goto_locus = gimple_location (goto_t);
1007 assign_discriminator (e->goto_locus, label_bb);
1009 e->goto_block = gimple_block (goto_t);
1010 gsi_remove (&last, true);
1014 /* A computed GOTO creates abnormal edges. */
1015 make_abnormal_goto_edges (bb, false);
1018 /* Create edges for an asm statement with labels at block BB. */
1021 make_gimple_asm_edges (basic_block bb)
1023 gimple stmt = last_stmt (bb);
1024 location_t stmt_loc = gimple_location (stmt);
1025 int i, n = gimple_asm_nlabels (stmt);
1027 for (i = 0; i < n; ++i)
1029 tree label = TREE_VALUE (gimple_asm_label_op (stmt, i));
1030 basic_block label_bb = label_to_block (label);
1031 make_edge (bb, label_bb, 0);
1032 assign_discriminator (stmt_loc, label_bb);
1036 /*---------------------------------------------------------------------------
1038 ---------------------------------------------------------------------------*/
1040 /* Cleanup useless labels in basic blocks. This is something we wish
1041 to do early because it allows us to group case labels before creating
1042 the edges for the CFG, and it speeds up block statement iterators in
1043 all passes later on.
1044 We rerun this pass after CFG is created, to get rid of the labels that
1045 are no longer referenced. After then we do not run it any more, since
1046 (almost) no new labels should be created. */
1048 /* A map from basic block index to the leading label of that block. */
1049 static struct label_record
1054 /* True if the label is referenced from somewhere. */
1058 /* Given LABEL return the first label in the same basic block. */
1061 main_block_label (tree label)
1063 basic_block bb = label_to_block (label);
1064 tree main_label = label_for_bb[bb->index].label;
1066 /* label_to_block possibly inserted undefined label into the chain. */
1069 label_for_bb[bb->index].label = label;
1073 label_for_bb[bb->index].used = true;
1077 /* Clean up redundant labels within the exception tree. */
1080 cleanup_dead_labels_eh (void)
1087 if (cfun->eh == NULL)
1090 for (i = 1; VEC_iterate (eh_landing_pad, cfun->eh->lp_array, i, lp); ++i)
1091 if (lp && lp->post_landing_pad)
1093 lab = main_block_label (lp->post_landing_pad);
1094 if (lab != lp->post_landing_pad)
1096 EH_LANDING_PAD_NR (lp->post_landing_pad) = 0;
1097 EH_LANDING_PAD_NR (lab) = lp->index;
1101 FOR_ALL_EH_REGION (r)
1105 case ERT_MUST_NOT_THROW:
1111 for (c = r->u.eh_try.first_catch; c ; c = c->next_catch)
1115 c->label = main_block_label (lab);
1120 case ERT_ALLOWED_EXCEPTIONS:
1121 lab = r->u.allowed.label;
1123 r->u.allowed.label = main_block_label (lab);
1129 /* Cleanup redundant labels. This is a three-step process:
1130 1) Find the leading label for each block.
1131 2) Redirect all references to labels to the leading labels.
1132 3) Cleanup all useless labels. */
1135 cleanup_dead_labels (void)
1138 label_for_bb = XCNEWVEC (struct label_record, last_basic_block);
1140 /* Find a suitable label for each block. We use the first user-defined
1141 label if there is one, or otherwise just the first label we see. */
1144 gimple_stmt_iterator i;
1146 for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
1149 gimple stmt = gsi_stmt (i);
1151 if (gimple_code (stmt) != GIMPLE_LABEL)
1154 label = gimple_label_label (stmt);
1156 /* If we have not yet seen a label for the current block,
1157 remember this one and see if there are more labels. */
1158 if (!label_for_bb[bb->index].label)
1160 label_for_bb[bb->index].label = label;
1164 /* If we did see a label for the current block already, but it
1165 is an artificially created label, replace it if the current
1166 label is a user defined label. */
1167 if (!DECL_ARTIFICIAL (label)
1168 && DECL_ARTIFICIAL (label_for_bb[bb->index].label))
1170 label_for_bb[bb->index].label = label;
1176 /* Now redirect all jumps/branches to the selected label.
1177 First do so for each block ending in a control statement. */
1180 gimple stmt = last_stmt (bb);
1184 switch (gimple_code (stmt))
1188 tree true_label = gimple_cond_true_label (stmt);
1189 tree false_label = gimple_cond_false_label (stmt);
1192 gimple_cond_set_true_label (stmt, main_block_label (true_label));
1194 gimple_cond_set_false_label (stmt, main_block_label (false_label));
1200 size_t i, n = gimple_switch_num_labels (stmt);
1202 /* Replace all destination labels. */
1203 for (i = 0; i < n; ++i)
1205 tree case_label = gimple_switch_label (stmt, i);
1206 tree label = main_block_label (CASE_LABEL (case_label));
1207 CASE_LABEL (case_label) = label;
1214 int i, n = gimple_asm_nlabels (stmt);
1216 for (i = 0; i < n; ++i)
1218 tree cons = gimple_asm_label_op (stmt, i);
1219 tree label = main_block_label (TREE_VALUE (cons));
1220 TREE_VALUE (cons) = label;
1225 /* We have to handle gotos until they're removed, and we don't
1226 remove them until after we've created the CFG edges. */
1228 if (!computed_goto_p (stmt))
1230 tree new_dest = main_block_label (gimple_goto_dest (stmt));
1231 gimple_goto_set_dest (stmt, new_dest);
1240 /* Do the same for the exception region tree labels. */
1241 cleanup_dead_labels_eh ();
1243 /* Finally, purge dead labels. All user-defined labels and labels that
1244 can be the target of non-local gotos and labels which have their
1245 address taken are preserved. */
1248 gimple_stmt_iterator i;
1249 tree label_for_this_bb = label_for_bb[bb->index].label;
1251 if (!label_for_this_bb)
1254 /* If the main label of the block is unused, we may still remove it. */
1255 if (!label_for_bb[bb->index].used)
1256 label_for_this_bb = NULL;
1258 for (i = gsi_start_bb (bb); !gsi_end_p (i); )
1261 gimple stmt = gsi_stmt (i);
1263 if (gimple_code (stmt) != GIMPLE_LABEL)
1266 label = gimple_label_label (stmt);
1268 if (label == label_for_this_bb
1269 || !DECL_ARTIFICIAL (label)
1270 || DECL_NONLOCAL (label)
1271 || FORCED_LABEL (label))
1274 gsi_remove (&i, true);
1278 free (label_for_bb);
1281 /* Look for blocks ending in a multiway branch (a SWITCH_EXPR in GIMPLE),
1282 and scan the sorted vector of cases. Combine the ones jumping to the
1284 Eg. three separate entries 1: 2: 3: become one entry 1..3: */
1287 group_case_labels (void)
1293 gimple stmt = last_stmt (bb);
1294 if (stmt && gimple_code (stmt) == GIMPLE_SWITCH)
1296 int old_size = gimple_switch_num_labels (stmt);
1297 int i, j, new_size = old_size;
1298 tree default_case = NULL_TREE;
1299 tree default_label = NULL_TREE;
1302 /* The default label is always the first case in a switch
1303 statement after gimplification if it was not optimized
1305 if (!CASE_LOW (gimple_switch_default_label (stmt))
1306 && !CASE_HIGH (gimple_switch_default_label (stmt)))
1308 default_case = gimple_switch_default_label (stmt);
1309 default_label = CASE_LABEL (default_case);
1313 has_default = false;
1315 /* Look for possible opportunities to merge cases. */
1320 while (i < old_size)
1322 tree base_case, base_label, base_high;
1323 base_case = gimple_switch_label (stmt, i);
1325 gcc_assert (base_case);
1326 base_label = CASE_LABEL (base_case);
1328 /* Discard cases that have the same destination as the
1330 if (base_label == default_label)
1332 gimple_switch_set_label (stmt, i, NULL_TREE);
1338 base_high = CASE_HIGH (base_case)
1339 ? CASE_HIGH (base_case)
1340 : CASE_LOW (base_case);
1343 /* Try to merge case labels. Break out when we reach the end
1344 of the label vector or when we cannot merge the next case
1345 label with the current one. */
1346 while (i < old_size)
1348 tree merge_case = gimple_switch_label (stmt, i);
1349 tree merge_label = CASE_LABEL (merge_case);
1350 tree t = int_const_binop (PLUS_EXPR, base_high,
1351 integer_one_node, 1);
1353 /* Merge the cases if they jump to the same place,
1354 and their ranges are consecutive. */
1355 if (merge_label == base_label
1356 && tree_int_cst_equal (CASE_LOW (merge_case), t))
1358 base_high = CASE_HIGH (merge_case) ?
1359 CASE_HIGH (merge_case) : CASE_LOW (merge_case);
1360 CASE_HIGH (base_case) = base_high;
1361 gimple_switch_set_label (stmt, i, NULL_TREE);
1370 /* Compress the case labels in the label vector, and adjust the
1371 length of the vector. */
1372 for (i = 0, j = 0; i < new_size; i++)
1374 while (! gimple_switch_label (stmt, j))
1376 gimple_switch_set_label (stmt, i,
1377 gimple_switch_label (stmt, j++));
1380 gcc_assert (new_size <= old_size);
1381 gimple_switch_set_num_labels (stmt, new_size);
1386 /* Checks whether we can merge block B into block A. */
1389 gimple_can_merge_blocks_p (basic_block a, basic_block b)
1392 gimple_stmt_iterator gsi;
1395 if (!single_succ_p (a))
1398 if (single_succ_edge (a)->flags & (EDGE_ABNORMAL | EDGE_EH))
1401 if (single_succ (a) != b)
1404 if (!single_pred_p (b))
1407 if (b == EXIT_BLOCK_PTR)
1410 /* If A ends by a statement causing exceptions or something similar, we
1411 cannot merge the blocks. */
1412 stmt = last_stmt (a);
1413 if (stmt && stmt_ends_bb_p (stmt))
1416 /* Do not allow a block with only a non-local label to be merged. */
1418 && gimple_code (stmt) == GIMPLE_LABEL
1419 && DECL_NONLOCAL (gimple_label_label (stmt)))
1422 /* Examine the labels at the beginning of B. */
1423 for (gsi = gsi_start_bb (b); !gsi_end_p (gsi); gsi_next (&gsi))
1426 stmt = gsi_stmt (gsi);
1427 if (gimple_code (stmt) != GIMPLE_LABEL)
1429 lab = gimple_label_label (stmt);
1431 /* Do not remove user labels. */
1432 if (!DECL_ARTIFICIAL (lab))
1436 /* Protect the loop latches. */
1437 if (current_loops && b->loop_father->latch == b)
1440 /* It must be possible to eliminate all phi nodes in B. If ssa form
1441 is not up-to-date, we cannot eliminate any phis; however, if only
1442 some symbols as whole are marked for renaming, this is not a problem,
1443 as phi nodes for those symbols are irrelevant in updating anyway. */
1444 phis = phi_nodes (b);
1445 if (!gimple_seq_empty_p (phis))
1447 gimple_stmt_iterator i;
1449 if (name_mappings_registered_p ())
1452 for (i = gsi_start (phis); !gsi_end_p (i); gsi_next (&i))
1454 gimple phi = gsi_stmt (i);
1456 if (!is_gimple_reg (gimple_phi_result (phi))
1457 && !may_propagate_copy (gimple_phi_result (phi),
1458 gimple_phi_arg_def (phi, 0)))
1466 /* Return true if the var whose chain of uses starts at PTR has no
1469 has_zero_uses_1 (const ssa_use_operand_t *head)
1471 const ssa_use_operand_t *ptr;
1473 for (ptr = head->next; ptr != head; ptr = ptr->next)
1474 if (!is_gimple_debug (USE_STMT (ptr)))
1480 /* Return true if the var whose chain of uses starts at PTR has a
1481 single nondebug use. Set USE_P and STMT to that single nondebug
1482 use, if so, or to NULL otherwise. */
1484 single_imm_use_1 (const ssa_use_operand_t *head,
1485 use_operand_p *use_p, gimple *stmt)
1487 ssa_use_operand_t *ptr, *single_use = 0;
1489 for (ptr = head->next; ptr != head; ptr = ptr->next)
1490 if (!is_gimple_debug (USE_STMT (ptr)))
1501 *use_p = single_use;
1504 *stmt = single_use ? single_use->loc.stmt : NULL;
1506 return !!single_use;
1509 /* Replaces all uses of NAME by VAL. */
1512 replace_uses_by (tree name, tree val)
1514 imm_use_iterator imm_iter;
1519 FOR_EACH_IMM_USE_STMT (stmt, imm_iter, name)
1521 FOR_EACH_IMM_USE_ON_STMT (use, imm_iter)
1523 replace_exp (use, val);
1525 if (gimple_code (stmt) == GIMPLE_PHI)
1527 e = gimple_phi_arg_edge (stmt, PHI_ARG_INDEX_FROM_USE (use));
1528 if (e->flags & EDGE_ABNORMAL)
1530 /* This can only occur for virtual operands, since
1531 for the real ones SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name))
1532 would prevent replacement. */
1533 gcc_assert (!is_gimple_reg (name));
1534 SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val) = 1;
1539 if (gimple_code (stmt) != GIMPLE_PHI)
1543 fold_stmt_inplace (stmt);
1544 if (cfgcleanup_altered_bbs)
1545 bitmap_set_bit (cfgcleanup_altered_bbs, gimple_bb (stmt)->index);
1547 /* FIXME. This should go in update_stmt. */
1548 for (i = 0; i < gimple_num_ops (stmt); i++)
1550 tree op = gimple_op (stmt, i);
1551 /* Operands may be empty here. For example, the labels
1552 of a GIMPLE_COND are nulled out following the creation
1553 of the corresponding CFG edges. */
1554 if (op && TREE_CODE (op) == ADDR_EXPR)
1555 recompute_tree_invariant_for_addr_expr (op);
1558 maybe_clean_or_replace_eh_stmt (stmt, stmt);
1563 gcc_assert (has_zero_uses (name));
1565 /* Also update the trees stored in loop structures. */
1571 FOR_EACH_LOOP (li, loop, 0)
1573 substitute_in_loop_info (loop, name, val);
1578 /* Merge block B into block A. */
1581 gimple_merge_blocks (basic_block a, basic_block b)
1583 gimple_stmt_iterator last, gsi, psi;
1584 gimple_seq phis = phi_nodes (b);
1587 fprintf (dump_file, "Merging blocks %d and %d\n", a->index, b->index);
1589 /* Remove all single-valued PHI nodes from block B of the form
1590 V_i = PHI <V_j> by propagating V_j to all the uses of V_i. */
1591 gsi = gsi_last_bb (a);
1592 for (psi = gsi_start (phis); !gsi_end_p (psi); )
1594 gimple phi = gsi_stmt (psi);
1595 tree def = gimple_phi_result (phi), use = gimple_phi_arg_def (phi, 0);
1597 bool may_replace_uses = !is_gimple_reg (def)
1598 || may_propagate_copy (def, use);
1600 /* In case we maintain loop closed ssa form, do not propagate arguments
1601 of loop exit phi nodes. */
1603 && loops_state_satisfies_p (LOOP_CLOSED_SSA)
1604 && is_gimple_reg (def)
1605 && TREE_CODE (use) == SSA_NAME
1606 && a->loop_father != b->loop_father)
1607 may_replace_uses = false;
1609 if (!may_replace_uses)
1611 gcc_assert (is_gimple_reg (def));
1613 /* Note that just emitting the copies is fine -- there is no problem
1614 with ordering of phi nodes. This is because A is the single
1615 predecessor of B, therefore results of the phi nodes cannot
1616 appear as arguments of the phi nodes. */
1617 copy = gimple_build_assign (def, use);
1618 gsi_insert_after (&gsi, copy, GSI_NEW_STMT);
1619 remove_phi_node (&psi, false);
1623 /* If we deal with a PHI for virtual operands, we can simply
1624 propagate these without fussing with folding or updating
1626 if (!is_gimple_reg (def))
1628 imm_use_iterator iter;
1629 use_operand_p use_p;
1632 FOR_EACH_IMM_USE_STMT (stmt, iter, def)
1633 FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
1634 SET_USE (use_p, use);
1637 replace_uses_by (def, use);
1639 remove_phi_node (&psi, true);
1643 /* Ensure that B follows A. */
1644 move_block_after (b, a);
1646 gcc_assert (single_succ_edge (a)->flags & EDGE_FALLTHRU);
1647 gcc_assert (!last_stmt (a) || !stmt_ends_bb_p (last_stmt (a)));
1649 /* Remove labels from B and set gimple_bb to A for other statements. */
1650 for (gsi = gsi_start_bb (b); !gsi_end_p (gsi);)
1652 gimple stmt = gsi_stmt (gsi);
1653 if (gimple_code (stmt) == GIMPLE_LABEL)
1655 tree label = gimple_label_label (stmt);
1658 gsi_remove (&gsi, false);
1660 /* Now that we can thread computed gotos, we might have
1661 a situation where we have a forced label in block B
1662 However, the label at the start of block B might still be
1663 used in other ways (think about the runtime checking for
1664 Fortran assigned gotos). So we can not just delete the
1665 label. Instead we move the label to the start of block A. */
1666 if (FORCED_LABEL (label))
1668 gimple_stmt_iterator dest_gsi = gsi_start_bb (a);
1669 gsi_insert_before (&dest_gsi, stmt, GSI_NEW_STMT);
1672 lp_nr = EH_LANDING_PAD_NR (label);
1675 eh_landing_pad lp = get_eh_landing_pad_from_number (lp_nr);
1676 lp->post_landing_pad = NULL;
1681 gimple_set_bb (stmt, a);
1686 /* Merge the sequences. */
1687 last = gsi_last_bb (a);
1688 gsi_insert_seq_after (&last, bb_seq (b), GSI_NEW_STMT);
1689 set_bb_seq (b, NULL);
1691 if (cfgcleanup_altered_bbs)
1692 bitmap_set_bit (cfgcleanup_altered_bbs, a->index);
1696 /* Return the one of two successors of BB that is not reachable by a
1697 complex edge, if there is one. Else, return BB. We use
1698 this in optimizations that use post-dominators for their heuristics,
1699 to catch the cases in C++ where function calls are involved. */
1702 single_noncomplex_succ (basic_block bb)
1705 if (EDGE_COUNT (bb->succs) != 2)
1708 e0 = EDGE_SUCC (bb, 0);
1709 e1 = EDGE_SUCC (bb, 1);
1710 if (e0->flags & EDGE_COMPLEX)
1712 if (e1->flags & EDGE_COMPLEX)
1719 /* Walk the function tree removing unnecessary statements.
1721 * Empty statement nodes are removed
1723 * Unnecessary TRY_FINALLY and TRY_CATCH blocks are removed
1725 * Unnecessary COND_EXPRs are removed
1727 * Some unnecessary BIND_EXPRs are removed
1729 * GOTO_EXPRs immediately preceding destination are removed.
1731 Clearly more work could be done. The trick is doing the analysis
1732 and removal fast enough to be a net improvement in compile times.
1734 Note that when we remove a control structure such as a COND_EXPR
1735 BIND_EXPR, or TRY block, we will need to repeat this optimization pass
1736 to ensure we eliminate all the useless code. */
1745 gimple_stmt_iterator last_goto_gsi;
1749 static void remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *);
1751 /* Given a statement sequence, find the first executable statement with
1752 location information, and warn that it is unreachable. When searching,
1753 descend into containers in execution order. */
1756 remove_useless_stmts_warn_notreached (gimple_seq stmts)
1758 gimple_stmt_iterator gsi;
1760 for (gsi = gsi_start (stmts); !gsi_end_p (gsi); gsi_next (&gsi))
1762 gimple stmt = gsi_stmt (gsi);
1764 if (gimple_no_warning_p (stmt)) return false;
1766 if (gimple_has_location (stmt))
1768 location_t loc = gimple_location (stmt);
1769 if (LOCATION_LINE (loc) > 0)
1771 warning_at (loc, OPT_Wunreachable_code, "will never be executed");
1776 switch (gimple_code (stmt))
1778 /* Unfortunately, we need the CFG now to detect unreachable
1779 branches in a conditional, so conditionals are not handled here. */
1782 if (remove_useless_stmts_warn_notreached (gimple_try_eval (stmt)))
1784 if (remove_useless_stmts_warn_notreached (gimple_try_cleanup (stmt)))
1789 return remove_useless_stmts_warn_notreached (gimple_catch_handler (stmt));
1791 case GIMPLE_EH_FILTER:
1792 return remove_useless_stmts_warn_notreached (gimple_eh_filter_failure (stmt));
1795 return remove_useless_stmts_warn_notreached (gimple_bind_body (stmt));
1805 /* Helper for remove_useless_stmts_1. Handle GIMPLE_COND statements. */
1808 remove_useless_stmts_cond (gimple_stmt_iterator *gsi, struct rus_data *data)
1810 gimple stmt = gsi_stmt (*gsi);
1812 /* The folded result must still be a conditional statement. */
1814 gcc_assert (gsi_stmt (*gsi) == stmt);
1816 data->may_branch = true;
1818 /* Replace trivial conditionals with gotos. */
1819 if (gimple_cond_true_p (stmt))
1821 /* Goto THEN label. */
1822 tree then_label = gimple_cond_true_label (stmt);
1824 gsi_replace (gsi, gimple_build_goto (then_label), false);
1825 data->last_goto_gsi = *gsi;
1826 data->last_was_goto = true;
1827 data->repeat = true;
1829 else if (gimple_cond_false_p (stmt))
1831 /* Goto ELSE label. */
1832 tree else_label = gimple_cond_false_label (stmt);
1834 gsi_replace (gsi, gimple_build_goto (else_label), false);
1835 data->last_goto_gsi = *gsi;
1836 data->last_was_goto = true;
1837 data->repeat = true;
1841 tree then_label = gimple_cond_true_label (stmt);
1842 tree else_label = gimple_cond_false_label (stmt);
1844 if (then_label == else_label)
1846 /* Goto common destination. */
1847 gsi_replace (gsi, gimple_build_goto (then_label), false);
1848 data->last_goto_gsi = *gsi;
1849 data->last_was_goto = true;
1850 data->repeat = true;
1856 data->last_was_goto = false;
1859 /* Helper for remove_useless_stmts_1.
1860 Handle the try-finally case for GIMPLE_TRY statements. */
1863 remove_useless_stmts_tf (gimple_stmt_iterator *gsi, struct rus_data *data)
1865 bool save_may_branch, save_may_throw;
1866 bool this_may_branch, this_may_throw;
1868 gimple_seq eval_seq, cleanup_seq;
1869 gimple_stmt_iterator eval_gsi, cleanup_gsi;
1871 gimple stmt = gsi_stmt (*gsi);
1873 /* Collect may_branch and may_throw information for the body only. */
1874 save_may_branch = data->may_branch;
1875 save_may_throw = data->may_throw;
1876 data->may_branch = false;
1877 data->may_throw = false;
1878 data->last_was_goto = false;
1880 eval_seq = gimple_try_eval (stmt);
1881 eval_gsi = gsi_start (eval_seq);
1882 remove_useless_stmts_1 (&eval_gsi, data);
1884 this_may_branch = data->may_branch;
1885 this_may_throw = data->may_throw;
1886 data->may_branch |= save_may_branch;
1887 data->may_throw |= save_may_throw;
1888 data->last_was_goto = false;
1890 cleanup_seq = gimple_try_cleanup (stmt);
1891 cleanup_gsi = gsi_start (cleanup_seq);
1892 remove_useless_stmts_1 (&cleanup_gsi, data);
1894 /* If the body is empty, then we can emit the FINALLY block without
1895 the enclosing TRY_FINALLY_EXPR. */
1896 if (gimple_seq_empty_p (eval_seq))
1898 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1899 gsi_remove (gsi, false);
1900 data->repeat = true;
1903 /* If the handler is empty, then we can emit the TRY block without
1904 the enclosing TRY_FINALLY_EXPR. */
1905 else if (gimple_seq_empty_p (cleanup_seq))
1907 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1908 gsi_remove (gsi, false);
1909 data->repeat = true;
1912 /* If the body neither throws, nor branches, then we can safely
1913 string the TRY and FINALLY blocks together. */
1914 else if (!this_may_branch && !this_may_throw)
1916 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1917 gsi_insert_seq_before (gsi, cleanup_seq, GSI_SAME_STMT);
1918 gsi_remove (gsi, false);
1919 data->repeat = true;
1925 /* Helper for remove_useless_stmts_1.
1926 Handle the try-catch case for GIMPLE_TRY statements. */
1929 remove_useless_stmts_tc (gimple_stmt_iterator *gsi, struct rus_data *data)
1931 bool save_may_throw, this_may_throw;
1933 gimple_seq eval_seq, cleanup_seq, handler_seq, failure_seq;
1934 gimple_stmt_iterator eval_gsi, cleanup_gsi, handler_gsi, failure_gsi;
1936 gimple stmt = gsi_stmt (*gsi);
1938 /* Collect may_throw information for the body only. */
1939 save_may_throw = data->may_throw;
1940 data->may_throw = false;
1941 data->last_was_goto = false;
1943 eval_seq = gimple_try_eval (stmt);
1944 eval_gsi = gsi_start (eval_seq);
1945 remove_useless_stmts_1 (&eval_gsi, data);
1947 this_may_throw = data->may_throw;
1948 data->may_throw = save_may_throw;
1950 cleanup_seq = gimple_try_cleanup (stmt);
1952 /* If the body cannot throw, then we can drop the entire TRY_CATCH_EXPR. */
1953 if (!this_may_throw)
1955 if (warn_notreached)
1957 remove_useless_stmts_warn_notreached (cleanup_seq);
1959 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
1960 gsi_remove (gsi, false);
1961 data->repeat = true;
1965 /* Process the catch clause specially. We may be able to tell that
1966 no exceptions propagate past this point. */
1968 this_may_throw = true;
1969 cleanup_gsi = gsi_start (cleanup_seq);
1970 stmt = gsi_stmt (cleanup_gsi);
1971 data->last_was_goto = false;
1973 switch (gimple_code (stmt))
1976 /* If the first element is a catch, they all must be. */
1977 while (!gsi_end_p (cleanup_gsi))
1979 stmt = gsi_stmt (cleanup_gsi);
1980 /* If we catch all exceptions, then the body does not
1981 propagate exceptions past this point. */
1982 if (gimple_catch_types (stmt) == NULL)
1983 this_may_throw = false;
1984 data->last_was_goto = false;
1985 handler_seq = gimple_catch_handler (stmt);
1986 handler_gsi = gsi_start (handler_seq);
1987 remove_useless_stmts_1 (&handler_gsi, data);
1988 gsi_next (&cleanup_gsi);
1993 case GIMPLE_EH_FILTER:
1994 if (gimple_eh_filter_types (stmt) == NULL)
1995 this_may_throw = false;
1996 failure_seq = gimple_eh_filter_failure (stmt);
1997 failure_gsi = gsi_start (failure_seq);
1998 remove_useless_stmts_1 (&failure_gsi, data);
2002 case GIMPLE_EH_MUST_NOT_THROW:
2003 this_may_throw = false;
2008 /* Otherwise this is a list of cleanup statements. */
2009 remove_useless_stmts_1 (&cleanup_gsi, data);
2011 /* If the cleanup is empty, then we can emit the TRY block without
2012 the enclosing TRY_CATCH_EXPR. */
2013 if (gimple_seq_empty_p (cleanup_seq))
2015 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
2016 gsi_remove(gsi, false);
2017 data->repeat = true;
2024 data->may_throw |= this_may_throw;
2027 /* Helper for remove_useless_stmts_1. Handle GIMPLE_BIND statements. */
2030 remove_useless_stmts_bind (gimple_stmt_iterator *gsi, struct rus_data *data ATTRIBUTE_UNUSED)
2033 gimple_seq body_seq, fn_body_seq;
2034 gimple_stmt_iterator body_gsi;
2036 gimple stmt = gsi_stmt (*gsi);
2038 /* First remove anything underneath the BIND_EXPR. */
2040 body_seq = gimple_bind_body (stmt);
2041 body_gsi = gsi_start (body_seq);
2042 remove_useless_stmts_1 (&body_gsi, data);
2044 /* If the GIMPLE_BIND has no variables, then we can pull everything
2045 up one level and remove the GIMPLE_BIND, unless this is the toplevel
2046 GIMPLE_BIND for the current function or an inlined function.
2048 When this situation occurs we will want to apply this
2049 optimization again. */
2050 block = gimple_bind_block (stmt);
2051 fn_body_seq = gimple_body (current_function_decl);
2052 if (gimple_bind_vars (stmt) == NULL_TREE
2053 && (gimple_seq_empty_p (fn_body_seq)
2054 || stmt != gimple_seq_first_stmt (fn_body_seq))
2056 || ! BLOCK_ABSTRACT_ORIGIN (block)
2057 || (TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block))
2060 tree var = NULL_TREE;
2061 /* Even if there are no gimple_bind_vars, there might be other
2062 decls in BLOCK_VARS rendering the GIMPLE_BIND not useless. */
2063 if (block && !BLOCK_NUM_NONLOCALIZED_VARS (block))
2064 for (var = BLOCK_VARS (block); var; var = TREE_CHAIN (var))
2065 if (TREE_CODE (var) == IMPORTED_DECL)
2067 if (var || (block && BLOCK_NUM_NONLOCALIZED_VARS (block)))
2071 gsi_insert_seq_before (gsi, body_seq, GSI_SAME_STMT);
2072 gsi_remove (gsi, false);
2073 data->repeat = true;
2080 /* Helper for remove_useless_stmts_1. Handle GIMPLE_GOTO statements. */
2083 remove_useless_stmts_goto (gimple_stmt_iterator *gsi, struct rus_data *data)
2085 gimple stmt = gsi_stmt (*gsi);
2087 tree dest = gimple_goto_dest (stmt);
2089 data->may_branch = true;
2090 data->last_was_goto = false;
2092 /* Record iterator for last goto expr, so that we can delete it if unnecessary. */
2093 if (TREE_CODE (dest) == LABEL_DECL)
2095 data->last_goto_gsi = *gsi;
2096 data->last_was_goto = true;
2102 /* Helper for remove_useless_stmts_1. Handle GIMPLE_LABEL statements. */
2105 remove_useless_stmts_label (gimple_stmt_iterator *gsi, struct rus_data *data)
2107 gimple stmt = gsi_stmt (*gsi);
2109 tree label = gimple_label_label (stmt);
2111 data->has_label = true;
2113 /* We do want to jump across non-local label receiver code. */
2114 if (DECL_NONLOCAL (label))
2115 data->last_was_goto = false;
2117 else if (data->last_was_goto
2118 && gimple_goto_dest (gsi_stmt (data->last_goto_gsi)) == label)
2120 /* Replace the preceding GIMPLE_GOTO statement with
2121 a GIMPLE_NOP, which will be subsequently removed.
2122 In this way, we avoid invalidating other iterators
2123 active on the statement sequence. */
2124 gsi_replace(&data->last_goto_gsi, gimple_build_nop(), false);
2125 data->last_was_goto = false;
2126 data->repeat = true;
2129 /* ??? Add something here to delete unused labels. */
2135 /* T is CALL_EXPR. Set current_function_calls_* flags. */
2138 notice_special_calls (gimple call)
2140 int flags = gimple_call_flags (call);
2142 if (flags & ECF_MAY_BE_ALLOCA)
2143 cfun->calls_alloca = true;
2144 if (flags & ECF_RETURNS_TWICE)
2145 cfun->calls_setjmp = true;
2149 /* Clear flags set by notice_special_calls. Used by dead code removal
2150 to update the flags. */
2153 clear_special_calls (void)
2155 cfun->calls_alloca = false;
2156 cfun->calls_setjmp = false;
2159 /* Remove useless statements from a statement sequence, and perform
2160 some preliminary simplifications. */
2163 remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *data)
2165 while (!gsi_end_p (*gsi))
2167 gimple stmt = gsi_stmt (*gsi);
2169 switch (gimple_code (stmt))
2172 remove_useless_stmts_cond (gsi, data);
2176 remove_useless_stmts_goto (gsi, data);
2180 remove_useless_stmts_label (gsi, data);
2185 stmt = gsi_stmt (*gsi);
2186 data->last_was_goto = false;
2187 if (stmt_could_throw_p (stmt))
2188 data->may_throw = true;
2194 data->last_was_goto = false;
2200 stmt = gsi_stmt (*gsi);
2201 data->last_was_goto = false;
2202 if (is_gimple_call (stmt))
2203 notice_special_calls (stmt);
2205 /* We used to call update_gimple_call_flags here,
2206 which copied side-effects and nothrows status
2207 from the function decl to the call. In the new
2208 tuplified GIMPLE, the accessors for this information
2209 always consult the function decl, so this copying
2210 is no longer necessary. */
2211 if (stmt_could_throw_p (stmt))
2212 data->may_throw = true;
2218 data->last_was_goto = false;
2219 data->may_branch = true;
2224 remove_useless_stmts_bind (gsi, data);
2228 if (gimple_try_kind (stmt) == GIMPLE_TRY_CATCH)
2229 remove_useless_stmts_tc (gsi, data);
2230 else if (gimple_try_kind (stmt) == GIMPLE_TRY_FINALLY)
2231 remove_useless_stmts_tf (gsi, data);
2241 gsi_remove (gsi, false);
2244 case GIMPLE_OMP_FOR:
2246 gimple_seq pre_body_seq = gimple_omp_for_pre_body (stmt);
2247 gimple_stmt_iterator pre_body_gsi = gsi_start (pre_body_seq);
2249 remove_useless_stmts_1 (&pre_body_gsi, data);
2250 data->last_was_goto = false;
2253 case GIMPLE_OMP_CRITICAL:
2254 case GIMPLE_OMP_CONTINUE:
2255 case GIMPLE_OMP_MASTER:
2256 case GIMPLE_OMP_ORDERED:
2257 case GIMPLE_OMP_SECTION:
2258 case GIMPLE_OMP_SECTIONS:
2259 case GIMPLE_OMP_SINGLE:
2261 gimple_seq body_seq = gimple_omp_body (stmt);
2262 gimple_stmt_iterator body_gsi = gsi_start (body_seq);
2264 remove_useless_stmts_1 (&body_gsi, data);
2265 data->last_was_goto = false;
2270 case GIMPLE_OMP_PARALLEL:
2271 case GIMPLE_OMP_TASK:
2273 /* Make sure the outermost GIMPLE_BIND isn't removed
2275 gimple_seq body_seq = gimple_omp_body (stmt);
2276 gimple bind = gimple_seq_first_stmt (body_seq);
2277 gimple_seq bind_seq = gimple_bind_body (bind);
2278 gimple_stmt_iterator bind_gsi = gsi_start (bind_seq);
2280 remove_useless_stmts_1 (&bind_gsi, data);
2281 data->last_was_goto = false;
2287 data->last_was_goto = false;
2294 /* Walk the function tree, removing useless statements and performing
2295 some preliminary simplifications. */
2298 remove_useless_stmts (void)
2300 struct rus_data data;
2302 clear_special_calls ();
2306 gimple_stmt_iterator gsi;
2308 gsi = gsi_start (gimple_body (current_function_decl));
2309 memset (&data, 0, sizeof (data));
2310 remove_useless_stmts_1 (&gsi, &data);
2312 while (data.repeat);
2314 #ifdef ENABLE_TYPES_CHECKING
2315 verify_types_in_gimple_seq (gimple_body (current_function_decl));
2322 struct gimple_opt_pass pass_remove_useless_stmts =
2326 "useless", /* name */
2328 remove_useless_stmts, /* execute */
2331 0, /* static_pass_number */
2332 TV_NONE, /* tv_id */
2333 PROP_gimple_any, /* properties_required */
2334 0, /* properties_provided */
2335 0, /* properties_destroyed */
2336 0, /* todo_flags_start */
2337 TODO_dump_func /* todo_flags_finish */
2341 /* Remove PHI nodes associated with basic block BB and all edges out of BB. */
2344 remove_phi_nodes_and_edges_for_unreachable_block (basic_block bb)
2346 /* Since this block is no longer reachable, we can just delete all
2347 of its PHI nodes. */
2348 remove_phi_nodes (bb);
2350 /* Remove edges to BB's successors. */
2351 while (EDGE_COUNT (bb->succs) > 0)
2352 remove_edge (EDGE_SUCC (bb, 0));
2356 /* Remove statements of basic block BB. */
2359 remove_bb (basic_block bb)
2361 gimple_stmt_iterator i;
2362 source_location loc = UNKNOWN_LOCATION;
2366 fprintf (dump_file, "Removing basic block %d\n", bb->index);
2367 if (dump_flags & TDF_DETAILS)
2369 dump_bb (bb, dump_file, 0);
2370 fprintf (dump_file, "\n");
2376 struct loop *loop = bb->loop_father;
2378 /* If a loop gets removed, clean up the information associated
2380 if (loop->latch == bb
2381 || loop->header == bb)
2382 free_numbers_of_iterations_estimates_loop (loop);
2385 /* Remove all the instructions in the block. */
2386 if (bb_seq (bb) != NULL)
2388 /* Walk backwards so as to get a chance to substitute all
2389 released DEFs into debug stmts. See
2390 eliminate_unnecessary_stmts() in tree-ssa-dce.c for more
2392 for (i = gsi_last_bb (bb); !gsi_end_p (i);)
2394 gimple stmt = gsi_stmt (i);
2395 if (gimple_code (stmt) == GIMPLE_LABEL
2396 && (FORCED_LABEL (gimple_label_label (stmt))
2397 || DECL_NONLOCAL (gimple_label_label (stmt))))
2400 gimple_stmt_iterator new_gsi;
2402 /* A non-reachable non-local label may still be referenced.
2403 But it no longer needs to carry the extra semantics of
2405 if (DECL_NONLOCAL (gimple_label_label (stmt)))
2407 DECL_NONLOCAL (gimple_label_label (stmt)) = 0;
2408 FORCED_LABEL (gimple_label_label (stmt)) = 1;
2411 new_bb = bb->prev_bb;
2412 new_gsi = gsi_start_bb (new_bb);
2413 gsi_remove (&i, false);
2414 gsi_insert_before (&new_gsi, stmt, GSI_NEW_STMT);
2418 /* Release SSA definitions if we are in SSA. Note that we
2419 may be called when not in SSA. For example,
2420 final_cleanup calls this function via
2421 cleanup_tree_cfg. */
2422 if (gimple_in_ssa_p (cfun))
2423 release_defs (stmt);
2425 gsi_remove (&i, true);
2429 i = gsi_last_bb (bb);
2433 /* Don't warn for removed gotos. Gotos are often removed due to
2434 jump threading, thus resulting in bogus warnings. Not great,
2435 since this way we lose warnings for gotos in the original
2436 program that are indeed unreachable. */
2437 if (gimple_code (stmt) != GIMPLE_GOTO
2438 && gimple_has_location (stmt))
2439 loc = gimple_location (stmt);
2443 /* If requested, give a warning that the first statement in the
2444 block is unreachable. We walk statements backwards in the
2445 loop above, so the last statement we process is the first statement
2447 if (loc > BUILTINS_LOCATION && LOCATION_LINE (loc) > 0)
2448 warning_at (loc, OPT_Wunreachable_code, "will never be executed");
2450 remove_phi_nodes_and_edges_for_unreachable_block (bb);
2451 bb->il.gimple = NULL;
2455 /* Given a basic block BB ending with COND_EXPR or SWITCH_EXPR, and a
2456 predicate VAL, return the edge that will be taken out of the block.
2457 If VAL does not match a unique edge, NULL is returned. */
2460 find_taken_edge (basic_block bb, tree val)
2464 stmt = last_stmt (bb);
2467 gcc_assert (is_ctrl_stmt (stmt));
2472 if (!is_gimple_min_invariant (val))
2475 if (gimple_code (stmt) == GIMPLE_COND)
2476 return find_taken_edge_cond_expr (bb, val);
2478 if (gimple_code (stmt) == GIMPLE_SWITCH)
2479 return find_taken_edge_switch_expr (bb, val);
2481 if (computed_goto_p (stmt))
2483 /* Only optimize if the argument is a label, if the argument is
2484 not a label then we can not construct a proper CFG.
2486 It may be the case that we only need to allow the LABEL_REF to
2487 appear inside an ADDR_EXPR, but we also allow the LABEL_REF to
2488 appear inside a LABEL_EXPR just to be safe. */
2489 if ((TREE_CODE (val) == ADDR_EXPR || TREE_CODE (val) == LABEL_EXPR)
2490 && TREE_CODE (TREE_OPERAND (val, 0)) == LABEL_DECL)
2491 return find_taken_edge_computed_goto (bb, TREE_OPERAND (val, 0));
2498 /* Given a constant value VAL and the entry block BB to a GOTO_EXPR
2499 statement, determine which of the outgoing edges will be taken out of the
2500 block. Return NULL if either edge may be taken. */
2503 find_taken_edge_computed_goto (basic_block bb, tree val)
2508 dest = label_to_block (val);
2511 e = find_edge (bb, dest);
2512 gcc_assert (e != NULL);
2518 /* Given a constant value VAL and the entry block BB to a COND_EXPR
2519 statement, determine which of the two edges will be taken out of the
2520 block. Return NULL if either edge may be taken. */
2523 find_taken_edge_cond_expr (basic_block bb, tree val)
2525 edge true_edge, false_edge;
2527 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
2529 gcc_assert (TREE_CODE (val) == INTEGER_CST);
2530 return (integer_zerop (val) ? false_edge : true_edge);
2533 /* Given an INTEGER_CST VAL and the entry block BB to a SWITCH_EXPR
2534 statement, determine which edge will be taken out of the block. Return
2535 NULL if any edge may be taken. */
2538 find_taken_edge_switch_expr (basic_block bb, tree val)
2540 basic_block dest_bb;
2545 switch_stmt = last_stmt (bb);
2546 taken_case = find_case_label_for_value (switch_stmt, val);
2547 dest_bb = label_to_block (CASE_LABEL (taken_case));
2549 e = find_edge (bb, dest_bb);
2555 /* Return the CASE_LABEL_EXPR that SWITCH_STMT will take for VAL.
2556 We can make optimal use here of the fact that the case labels are
2557 sorted: We can do a binary search for a case matching VAL. */
2560 find_case_label_for_value (gimple switch_stmt, tree val)
2562 size_t low, high, n = gimple_switch_num_labels (switch_stmt);
2563 tree default_case = gimple_switch_default_label (switch_stmt);
2565 for (low = 0, high = n; high - low > 1; )
2567 size_t i = (high + low) / 2;
2568 tree t = gimple_switch_label (switch_stmt, i);
2571 /* Cache the result of comparing CASE_LOW and val. */
2572 cmp = tree_int_cst_compare (CASE_LOW (t), val);
2579 if (CASE_HIGH (t) == NULL)
2581 /* A singe-valued case label. */
2587 /* A case range. We can only handle integer ranges. */
2588 if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
2593 return default_case;
2597 /* Dump a basic block on stderr. */
2600 gimple_debug_bb (basic_block bb)
2602 gimple_dump_bb (bb, stderr, 0, TDF_VOPS|TDF_MEMSYMS);
2606 /* Dump basic block with index N on stderr. */
2609 gimple_debug_bb_n (int n)
2611 gimple_debug_bb (BASIC_BLOCK (n));
2612 return BASIC_BLOCK (n);
2616 /* Dump the CFG on stderr.
2618 FLAGS are the same used by the tree dumping functions
2619 (see TDF_* in tree-pass.h). */
2622 gimple_debug_cfg (int flags)
2624 gimple_dump_cfg (stderr, flags);
2628 /* Dump the program showing basic block boundaries on the given FILE.
2630 FLAGS are the same used by the tree dumping functions (see TDF_* in
2634 gimple_dump_cfg (FILE *file, int flags)
2636 if (flags & TDF_DETAILS)
2638 const char *funcname
2639 = lang_hooks.decl_printable_name (current_function_decl, 2);
2642 fprintf (file, ";; Function %s\n\n", funcname);
2643 fprintf (file, ";; \n%d basic blocks, %d edges, last basic block %d.\n\n",
2644 n_basic_blocks, n_edges, last_basic_block);
2646 brief_dump_cfg (file);
2647 fprintf (file, "\n");
2650 if (flags & TDF_STATS)
2651 dump_cfg_stats (file);
2653 dump_function_to_file (current_function_decl, file, flags | TDF_BLOCKS);
2657 /* Dump CFG statistics on FILE. */
2660 dump_cfg_stats (FILE *file)
2662 static long max_num_merged_labels = 0;
2663 unsigned long size, total = 0;
2666 const char * const fmt_str = "%-30s%-13s%12s\n";
2667 const char * const fmt_str_1 = "%-30s%13d%11lu%c\n";
2668 const char * const fmt_str_2 = "%-30s%13ld%11lu%c\n";
2669 const char * const fmt_str_3 = "%-43s%11lu%c\n";
2670 const char *funcname
2671 = lang_hooks.decl_printable_name (current_function_decl, 2);
2674 fprintf (file, "\nCFG Statistics for %s\n\n", funcname);
2676 fprintf (file, "---------------------------------------------------------\n");
2677 fprintf (file, fmt_str, "", " Number of ", "Memory");
2678 fprintf (file, fmt_str, "", " instances ", "used ");
2679 fprintf (file, "---------------------------------------------------------\n");
2681 size = n_basic_blocks * sizeof (struct basic_block_def);
2683 fprintf (file, fmt_str_1, "Basic blocks", n_basic_blocks,
2684 SCALE (size), LABEL (size));
2688 num_edges += EDGE_COUNT (bb->succs);
2689 size = num_edges * sizeof (struct edge_def);
2691 fprintf (file, fmt_str_2, "Edges", num_edges, SCALE (size), LABEL (size));
2693 fprintf (file, "---------------------------------------------------------\n");
2694 fprintf (file, fmt_str_3, "Total memory used by CFG data", SCALE (total),
2696 fprintf (file, "---------------------------------------------------------\n");
2697 fprintf (file, "\n");
2699 if (cfg_stats.num_merged_labels > max_num_merged_labels)
2700 max_num_merged_labels = cfg_stats.num_merged_labels;
2702 fprintf (file, "Coalesced label blocks: %ld (Max so far: %ld)\n",
2703 cfg_stats.num_merged_labels, max_num_merged_labels);
2705 fprintf (file, "\n");
2709 /* Dump CFG statistics on stderr. Keep extern so that it's always
2710 linked in the final executable. */
2713 debug_cfg_stats (void)
2715 dump_cfg_stats (stderr);
2719 /* Dump the flowgraph to a .vcg FILE. */
2722 gimple_cfg2vcg (FILE *file)
2727 const char *funcname
2728 = lang_hooks.decl_printable_name (current_function_decl, 2);
2730 /* Write the file header. */
2731 fprintf (file, "graph: { title: \"%s\"\n", funcname);
2732 fprintf (file, "node: { title: \"ENTRY\" label: \"ENTRY\" }\n");
2733 fprintf (file, "node: { title: \"EXIT\" label: \"EXIT\" }\n");
2735 /* Write blocks and edges. */
2736 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
2738 fprintf (file, "edge: { sourcename: \"ENTRY\" targetname: \"%d\"",
2741 if (e->flags & EDGE_FAKE)
2742 fprintf (file, " linestyle: dotted priority: 10");
2744 fprintf (file, " linestyle: solid priority: 100");
2746 fprintf (file, " }\n");
2752 enum gimple_code head_code, end_code;
2753 const char *head_name, *end_name;
2756 gimple first = first_stmt (bb);
2757 gimple last = last_stmt (bb);
2761 head_code = gimple_code (first);
2762 head_name = gimple_code_name[head_code];
2763 head_line = get_lineno (first);
2766 head_name = "no-statement";
2770 end_code = gimple_code (last);
2771 end_name = gimple_code_name[end_code];
2772 end_line = get_lineno (last);
2775 end_name = "no-statement";
2777 fprintf (file, "node: { title: \"%d\" label: \"#%d\\n%s (%d)\\n%s (%d)\"}\n",
2778 bb->index, bb->index, head_name, head_line, end_name,
2781 FOR_EACH_EDGE (e, ei, bb->succs)
2783 if (e->dest == EXIT_BLOCK_PTR)
2784 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"EXIT\"", bb->index);
2786 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"%d\"", bb->index, e->dest->index);
2788 if (e->flags & EDGE_FAKE)
2789 fprintf (file, " priority: 10 linestyle: dotted");
2791 fprintf (file, " priority: 100 linestyle: solid");
2793 fprintf (file, " }\n");
2796 if (bb->next_bb != EXIT_BLOCK_PTR)
2800 fputs ("}\n\n", file);
2805 /*---------------------------------------------------------------------------
2806 Miscellaneous helpers
2807 ---------------------------------------------------------------------------*/
2809 /* Return true if T represents a stmt that always transfers control. */
2812 is_ctrl_stmt (gimple t)
2814 switch (gimple_code (t))
2828 /* Return true if T is a statement that may alter the flow of control
2829 (e.g., a call to a non-returning function). */
2832 is_ctrl_altering_stmt (gimple t)
2836 switch (gimple_code (t))
2840 int flags = gimple_call_flags (t);
2842 /* A non-pure/const call alters flow control if the current
2843 function has nonlocal labels. */
2844 if (!(flags & (ECF_CONST | ECF_PURE)) && cfun->has_nonlocal_label)
2847 /* A call also alters control flow if it does not return. */
2848 if (gimple_call_flags (t) & ECF_NORETURN)
2853 case GIMPLE_EH_DISPATCH:
2854 /* EH_DISPATCH branches to the individual catch handlers at
2855 this level of a try or allowed-exceptions region. It can
2856 fallthru to the next statement as well. */
2860 if (gimple_asm_nlabels (t) > 0)
2865 /* OpenMP directives alter control flow. */
2872 /* If a statement can throw, it alters control flow. */
2873 return stmt_can_throw_internal (t);
2877 /* Return true if T is a simple local goto. */
2880 simple_goto_p (gimple t)
2882 return (gimple_code (t) == GIMPLE_GOTO
2883 && TREE_CODE (gimple_goto_dest (t)) == LABEL_DECL);
2887 /* Return true if T can make an abnormal transfer of control flow.
2888 Transfers of control flow associated with EH are excluded. */
2891 stmt_can_make_abnormal_goto (gimple t)
2893 if (computed_goto_p (t))
2895 if (is_gimple_call (t))
2896 return gimple_has_side_effects (t) && cfun->has_nonlocal_label;
2901 /* Return true if STMT should start a new basic block. PREV_STMT is
2902 the statement preceding STMT. It is used when STMT is a label or a
2903 case label. Labels should only start a new basic block if their
2904 previous statement wasn't a label. Otherwise, sequence of labels
2905 would generate unnecessary basic blocks that only contain a single
2909 stmt_starts_bb_p (gimple stmt, gimple prev_stmt)
2914 /* Labels start a new basic block only if the preceding statement
2915 wasn't a label of the same type. This prevents the creation of
2916 consecutive blocks that have nothing but a single label. */
2917 if (gimple_code (stmt) == GIMPLE_LABEL)
2919 /* Nonlocal and computed GOTO targets always start a new block. */
2920 if (DECL_NONLOCAL (gimple_label_label (stmt))
2921 || FORCED_LABEL (gimple_label_label (stmt)))
2924 if (prev_stmt && gimple_code (prev_stmt) == GIMPLE_LABEL)
2926 if (DECL_NONLOCAL (gimple_label_label (prev_stmt)))
2929 cfg_stats.num_merged_labels++;
2940 /* Return true if T should end a basic block. */
2943 stmt_ends_bb_p (gimple t)
2945 return is_ctrl_stmt (t) || is_ctrl_altering_stmt (t);
2948 /* Remove block annotations and other data structures. */
2951 delete_tree_cfg_annotations (void)
2953 label_to_block_map = NULL;
2957 /* Return the first statement in basic block BB. */
2960 first_stmt (basic_block bb)
2962 gimple_stmt_iterator i = gsi_start_bb (bb);
2965 while (!gsi_end_p (i) && is_gimple_debug ((stmt = gsi_stmt (i))))
2973 /* Return the first non-label statement in basic block BB. */
2976 first_non_label_stmt (basic_block bb)
2978 gimple_stmt_iterator i = gsi_start_bb (bb);
2979 while (!gsi_end_p (i) && gimple_code (gsi_stmt (i)) == GIMPLE_LABEL)
2981 return !gsi_end_p (i) ? gsi_stmt (i) : NULL;
2984 /* Return the last statement in basic block BB. */
2987 last_stmt (basic_block bb)
2989 gimple_stmt_iterator i = gsi_last_bb (bb);
2992 while (!gsi_end_p (i) && is_gimple_debug ((stmt = gsi_stmt (i))))
3000 /* Return the last statement of an otherwise empty block. Return NULL
3001 if the block is totally empty, or if it contains more than one
3005 last_and_only_stmt (basic_block bb)
3007 gimple_stmt_iterator i = gsi_last_nondebug_bb (bb);
3013 last = gsi_stmt (i);
3014 gsi_prev_nondebug (&i);
3018 /* Empty statements should no longer appear in the instruction stream.
3019 Everything that might have appeared before should be deleted by
3020 remove_useless_stmts, and the optimizers should just gsi_remove
3021 instead of smashing with build_empty_stmt.
3023 Thus the only thing that should appear here in a block containing
3024 one executable statement is a label. */
3025 prev = gsi_stmt (i);
3026 if (gimple_code (prev) == GIMPLE_LABEL)
3032 /* Reinstall those PHI arguments queued in OLD_EDGE to NEW_EDGE. */
3035 reinstall_phi_args (edge new_edge, edge old_edge)
3037 edge_var_map_vector v;
3040 gimple_stmt_iterator phis;
3042 v = redirect_edge_var_map_vector (old_edge);
3046 for (i = 0, phis = gsi_start_phis (new_edge->dest);
3047 VEC_iterate (edge_var_map, v, i, vm) && !gsi_end_p (phis);
3048 i++, gsi_next (&phis))
3050 gimple phi = gsi_stmt (phis);
3051 tree result = redirect_edge_var_map_result (vm);
3052 tree arg = redirect_edge_var_map_def (vm);
3054 gcc_assert (result == gimple_phi_result (phi));
3056 add_phi_arg (phi, arg, new_edge, redirect_edge_var_map_location (vm));
3059 redirect_edge_var_map_clear (old_edge);
3062 /* Returns the basic block after which the new basic block created
3063 by splitting edge EDGE_IN should be placed. Tries to keep the new block
3064 near its "logical" location. This is of most help to humans looking
3065 at debugging dumps. */
3068 split_edge_bb_loc (edge edge_in)
3070 basic_block dest = edge_in->dest;
3071 basic_block dest_prev = dest->prev_bb;
3075 edge e = find_edge (dest_prev, dest);
3076 if (e && !(e->flags & EDGE_COMPLEX))
3077 return edge_in->src;
3082 /* Split a (typically critical) edge EDGE_IN. Return the new block.
3083 Abort on abnormal edges. */
3086 gimple_split_edge (edge edge_in)
3088 basic_block new_bb, after_bb, dest;
3091 /* Abnormal edges cannot be split. */
3092 gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
3094 dest = edge_in->dest;
3096 after_bb = split_edge_bb_loc (edge_in);
3098 new_bb = create_empty_bb (after_bb);
3099 new_bb->frequency = EDGE_FREQUENCY (edge_in);
3100 new_bb->count = edge_in->count;
3101 new_edge = make_edge (new_bb, dest, EDGE_FALLTHRU);
3102 new_edge->probability = REG_BR_PROB_BASE;
3103 new_edge->count = edge_in->count;
3105 e = redirect_edge_and_branch (edge_in, new_bb);
3106 gcc_assert (e == edge_in);
3107 reinstall_phi_args (new_edge, e);
3112 /* Callback for walk_tree, check that all elements with address taken are
3113 properly noticed as such. The DATA is an int* that is 1 if TP was seen
3114 inside a PHI node. */
3117 verify_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
3124 /* Check operand N for being valid GIMPLE and give error MSG if not. */
3125 #define CHECK_OP(N, MSG) \
3126 do { if (!is_gimple_val (TREE_OPERAND (t, N))) \
3127 { error (MSG); return TREE_OPERAND (t, N); }} while (0)
3129 switch (TREE_CODE (t))
3132 if (SSA_NAME_IN_FREE_LIST (t))
3134 error ("SSA name in freelist but still referenced");
3140 x = TREE_OPERAND (t, 0);
3141 if (!is_gimple_reg (x) && !is_gimple_min_invariant (x))
3143 error ("Indirect reference's operand is not a register or a constant.");
3149 x = fold (ASSERT_EXPR_COND (t));
3150 if (x == boolean_false_node)
3152 error ("ASSERT_EXPR with an always-false condition");
3158 error ("MODIFY_EXPR not expected while having tuples.");
3164 bool old_side_effects;
3166 bool new_side_effects;
3168 gcc_assert (is_gimple_address (t));
3170 old_constant = TREE_CONSTANT (t);
3171 old_side_effects = TREE_SIDE_EFFECTS (t);
3173 recompute_tree_invariant_for_addr_expr (t);
3174 new_side_effects = TREE_SIDE_EFFECTS (t);
3175 new_constant = TREE_CONSTANT (t);
3177 if (old_constant != new_constant)
3179 error ("constant not recomputed when ADDR_EXPR changed");
3182 if (old_side_effects != new_side_effects)
3184 error ("side effects not recomputed when ADDR_EXPR changed");
3188 /* Skip any references (they will be checked when we recurse down the
3189 tree) and ensure that any variable used as a prefix is marked
3191 for (x = TREE_OPERAND (t, 0);
3192 handled_component_p (x);
3193 x = TREE_OPERAND (x, 0))
3196 if (!(TREE_CODE (x) == VAR_DECL
3197 || TREE_CODE (x) == PARM_DECL
3198 || TREE_CODE (x) == RESULT_DECL))
3200 if (!TREE_ADDRESSABLE (x))
3202 error ("address taken, but ADDRESSABLE bit not set");
3205 if (DECL_GIMPLE_REG_P (x))
3207 error ("DECL_GIMPLE_REG_P set on a variable with address taken");
3215 x = COND_EXPR_COND (t);
3216 if (!INTEGRAL_TYPE_P (TREE_TYPE (x)))
3218 error ("non-integral used in condition");
3221 if (!is_gimple_condexpr (x))
3223 error ("invalid conditional operand");
3228 case NON_LVALUE_EXPR:
3232 case FIX_TRUNC_EXPR:
3237 case TRUTH_NOT_EXPR:
3238 CHECK_OP (0, "invalid operand to unary operator");
3245 case ARRAY_RANGE_REF:
3247 case VIEW_CONVERT_EXPR:
3248 /* We have a nest of references. Verify that each of the operands
3249 that determine where to reference is either a constant or a variable,
3250 verify that the base is valid, and then show we've already checked
3252 while (handled_component_p (t))
3254 if (TREE_CODE (t) == COMPONENT_REF && TREE_OPERAND (t, 2))
3255 CHECK_OP (2, "invalid COMPONENT_REF offset operator");
3256 else if (TREE_CODE (t) == ARRAY_REF
3257 || TREE_CODE (t) == ARRAY_RANGE_REF)
3259 CHECK_OP (1, "invalid array index");
3260 if (TREE_OPERAND (t, 2))
3261 CHECK_OP (2, "invalid array lower bound");
3262 if (TREE_OPERAND (t, 3))
3263 CHECK_OP (3, "invalid array stride");
3265 else if (TREE_CODE (t) == BIT_FIELD_REF)
3267 if (!host_integerp (TREE_OPERAND (t, 1), 1)
3268 || !host_integerp (TREE_OPERAND (t, 2), 1))
3270 error ("invalid position or size operand to BIT_FIELD_REF");
3273 else if (INTEGRAL_TYPE_P (TREE_TYPE (t))
3274 && (TYPE_PRECISION (TREE_TYPE (t))
3275 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
3277 error ("integral result type precision does not match "
3278 "field size of BIT_FIELD_REF");
3281 if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
3282 && (GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (t)))
3283 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
3285 error ("mode precision of non-integral result does not "
3286 "match field size of BIT_FIELD_REF");
3291 t = TREE_OPERAND (t, 0);
3294 if (!is_gimple_min_invariant (t) && !is_gimple_lvalue (t))
3296 error ("invalid reference prefix");
3303 /* PLUS_EXPR and MINUS_EXPR don't work on pointers, they should be done using
3304 POINTER_PLUS_EXPR. */
3305 if (POINTER_TYPE_P (TREE_TYPE (t)))
3307 error ("invalid operand to plus/minus, type is a pointer");
3310 CHECK_OP (0, "invalid operand to binary operator");
3311 CHECK_OP (1, "invalid operand to binary operator");
3314 case POINTER_PLUS_EXPR:
3315 /* Check to make sure the first operand is a pointer or reference type. */
3316 if (!POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 0))))
3318 error ("invalid operand to pointer plus, first operand is not a pointer");
3321 /* Check to make sure the second operand is an integer with type of
3323 if (!useless_type_conversion_p (sizetype,
3324 TREE_TYPE (TREE_OPERAND (t, 1))))
3326 error ("invalid operand to pointer plus, second operand is not an "
3327 "integer with type of sizetype.");
3337 case UNORDERED_EXPR:
3346 case TRUNC_DIV_EXPR:
3348 case FLOOR_DIV_EXPR:
3349 case ROUND_DIV_EXPR:
3350 case TRUNC_MOD_EXPR:
3352 case FLOOR_MOD_EXPR:
3353 case ROUND_MOD_EXPR:
3355 case EXACT_DIV_EXPR:
3365 CHECK_OP (0, "invalid operand to binary operator");
3366 CHECK_OP (1, "invalid operand to binary operator");
3370 if (TREE_CONSTANT (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
3383 /* Verify if EXPR is either a GIMPLE ID or a GIMPLE indirect reference.
3384 Returns true if there is an error, otherwise false. */
3387 verify_types_in_gimple_min_lval (tree expr)
3391 if (is_gimple_id (expr))
3394 if (!INDIRECT_REF_P (expr)
3395 && TREE_CODE (expr) != TARGET_MEM_REF)
3397 error ("invalid expression for min lvalue");
3401 /* TARGET_MEM_REFs are strange beasts. */
3402 if (TREE_CODE (expr) == TARGET_MEM_REF)
3405 op = TREE_OPERAND (expr, 0);
3406 if (!is_gimple_val (op))
3408 error ("invalid operand in indirect reference");
3409 debug_generic_stmt (op);
3412 if (!useless_type_conversion_p (TREE_TYPE (expr),
3413 TREE_TYPE (TREE_TYPE (op))))
3415 error ("type mismatch in indirect reference");
3416 debug_generic_stmt (TREE_TYPE (expr));
3417 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3424 /* Verify if EXPR is a valid GIMPLE reference expression. If
3425 REQUIRE_LVALUE is true verifies it is an lvalue. Returns true
3426 if there is an error, otherwise false. */
3429 verify_types_in_gimple_reference (tree expr, bool require_lvalue)
3431 while (handled_component_p (expr))
3433 tree op = TREE_OPERAND (expr, 0);
3435 if (TREE_CODE (expr) == ARRAY_REF
3436 || TREE_CODE (expr) == ARRAY_RANGE_REF)
3438 if (!is_gimple_val (TREE_OPERAND (expr, 1))
3439 || (TREE_OPERAND (expr, 2)
3440 && !is_gimple_val (TREE_OPERAND (expr, 2)))
3441 || (TREE_OPERAND (expr, 3)
3442 && !is_gimple_val (TREE_OPERAND (expr, 3))))
3444 error ("invalid operands to array reference");
3445 debug_generic_stmt (expr);
3450 /* Verify if the reference array element types are compatible. */
3451 if (TREE_CODE (expr) == ARRAY_REF
3452 && !useless_type_conversion_p (TREE_TYPE (expr),
3453 TREE_TYPE (TREE_TYPE (op))))
3455 error ("type mismatch in array reference");
3456 debug_generic_stmt (TREE_TYPE (expr));
3457 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3460 if (TREE_CODE (expr) == ARRAY_RANGE_REF
3461 && !useless_type_conversion_p (TREE_TYPE (TREE_TYPE (expr)),
3462 TREE_TYPE (TREE_TYPE (op))))
3464 error ("type mismatch in array range reference");
3465 debug_generic_stmt (TREE_TYPE (TREE_TYPE (expr)));
3466 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3470 if ((TREE_CODE (expr) == REALPART_EXPR
3471 || TREE_CODE (expr) == IMAGPART_EXPR)
3472 && !useless_type_conversion_p (TREE_TYPE (expr),
3473 TREE_TYPE (TREE_TYPE (op))))
3475 error ("type mismatch in real/imagpart reference");
3476 debug_generic_stmt (TREE_TYPE (expr));
3477 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3481 if (TREE_CODE (expr) == COMPONENT_REF
3482 && !useless_type_conversion_p (TREE_TYPE (expr),
3483 TREE_TYPE (TREE_OPERAND (expr, 1))))
3485 error ("type mismatch in component reference");
3486 debug_generic_stmt (TREE_TYPE (expr));
3487 debug_generic_stmt (TREE_TYPE (TREE_OPERAND (expr, 1)));
3491 /* For VIEW_CONVERT_EXPRs which are allowed here, too, there
3492 is nothing to verify. Gross mismatches at most invoke
3493 undefined behavior. */
3494 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR
3495 && !handled_component_p (op))
3501 return ((require_lvalue || !is_gimple_min_invariant (expr))
3502 && verify_types_in_gimple_min_lval (expr));
3505 /* Returns true if there is one pointer type in TYPE_POINTER_TO (SRC_OBJ)
3506 list of pointer-to types that is trivially convertible to DEST. */
3509 one_pointer_to_useless_type_conversion_p (tree dest, tree src_obj)
3513 if (!TYPE_POINTER_TO (src_obj))
3516 for (src = TYPE_POINTER_TO (src_obj); src; src = TYPE_NEXT_PTR_TO (src))
3517 if (useless_type_conversion_p (dest, src))
3523 /* Return true if TYPE1 is a fixed-point type and if conversions to and
3524 from TYPE2 can be handled by FIXED_CONVERT_EXPR. */
3527 valid_fixed_convert_types_p (tree type1, tree type2)
3529 return (FIXED_POINT_TYPE_P (type1)
3530 && (INTEGRAL_TYPE_P (type2)
3531 || SCALAR_FLOAT_TYPE_P (type2)
3532 || FIXED_POINT_TYPE_P (type2)));
3535 /* Verify the contents of a GIMPLE_CALL STMT. Returns true when there
3536 is a problem, otherwise false. */
3539 verify_gimple_call (gimple stmt)
3541 tree fn = gimple_call_fn (stmt);
3544 if (!POINTER_TYPE_P (TREE_TYPE (fn))
3545 || (TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != FUNCTION_TYPE
3546 && TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != METHOD_TYPE))
3548 error ("non-function in gimple call");
3552 if (gimple_call_lhs (stmt)
3553 && !is_gimple_lvalue (gimple_call_lhs (stmt)))
3555 error ("invalid LHS in gimple call");
3559 fntype = TREE_TYPE (TREE_TYPE (fn));
3560 if (gimple_call_lhs (stmt)
3561 && !useless_type_conversion_p (TREE_TYPE (gimple_call_lhs (stmt)),
3563 /* ??? At least C++ misses conversions at assignments from
3564 void * call results.
3565 ??? Java is completely off. Especially with functions
3566 returning java.lang.Object.
3567 For now simply allow arbitrary pointer type conversions. */
3568 && !(POINTER_TYPE_P (TREE_TYPE (gimple_call_lhs (stmt)))
3569 && POINTER_TYPE_P (TREE_TYPE (fntype))))
3571 error ("invalid conversion in gimple call");
3572 debug_generic_stmt (TREE_TYPE (gimple_call_lhs (stmt)));
3573 debug_generic_stmt (TREE_TYPE (fntype));
3577 /* If there is a static chain argument, this should not be an indirect
3578 call, and the decl should have DECL_STATIC_CHAIN set. */
3579 if (gimple_call_chain (stmt))
3581 if (TREE_CODE (fn) != ADDR_EXPR
3582 || TREE_CODE (TREE_OPERAND (fn, 0)) != FUNCTION_DECL)
3584 error ("static chain in indirect gimple call");
3587 fn = TREE_OPERAND (fn, 0);
3589 if (!DECL_STATIC_CHAIN (fn))
3591 error ("static chain with function that doesn't use one");
3596 /* ??? The C frontend passes unpromoted arguments in case it
3597 didn't see a function declaration before the call. So for now
3598 leave the call arguments unverified. Once we gimplify
3599 unit-at-a-time we have a chance to fix this. */
3604 /* Verifies the gimple comparison with the result type TYPE and
3605 the operands OP0 and OP1. */
3608 verify_gimple_comparison (tree type, tree op0, tree op1)
3610 tree op0_type = TREE_TYPE (op0);
3611 tree op1_type = TREE_TYPE (op1);
3613 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3615 error ("invalid operands in gimple comparison");
3619 /* For comparisons we do not have the operations type as the
3620 effective type the comparison is carried out in. Instead
3621 we require that either the first operand is trivially
3622 convertible into the second, or the other way around.
3623 The resulting type of a comparison may be any integral type.
3624 Because we special-case pointers to void we allow
3625 comparisons of pointers with the same mode as well. */
3626 if ((!useless_type_conversion_p (op0_type, op1_type)
3627 && !useless_type_conversion_p (op1_type, op0_type)
3628 && (!POINTER_TYPE_P (op0_type)
3629 || !POINTER_TYPE_P (op1_type)
3630 || TYPE_MODE (op0_type) != TYPE_MODE (op1_type)))
3631 || !INTEGRAL_TYPE_P (type))
3633 error ("type mismatch in comparison expression");
3634 debug_generic_expr (type);
3635 debug_generic_expr (op0_type);
3636 debug_generic_expr (op1_type);
3643 /* Verify a gimple assignment statement STMT with an unary rhs.
3644 Returns true if anything is wrong. */
3647 verify_gimple_assign_unary (gimple stmt)
3649 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3650 tree lhs = gimple_assign_lhs (stmt);
3651 tree lhs_type = TREE_TYPE (lhs);
3652 tree rhs1 = gimple_assign_rhs1 (stmt);
3653 tree rhs1_type = TREE_TYPE (rhs1);
3655 if (!is_gimple_reg (lhs)
3657 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3659 error ("non-register as LHS of unary operation");
3663 if (!is_gimple_val (rhs1))
3665 error ("invalid operand in unary operation");
3669 /* First handle conversions. */
3674 /* Allow conversions between integral types and pointers only if
3675 there is no sign or zero extension involved.
3676 For targets were the precision of sizetype doesn't match that
3677 of pointers we need to allow arbitrary conversions from and
3679 if ((POINTER_TYPE_P (lhs_type)
3680 && INTEGRAL_TYPE_P (rhs1_type)
3681 && (TYPE_PRECISION (lhs_type) >= TYPE_PRECISION (rhs1_type)
3682 || rhs1_type == sizetype))
3683 || (POINTER_TYPE_P (rhs1_type)
3684 && INTEGRAL_TYPE_P (lhs_type)
3685 && (TYPE_PRECISION (rhs1_type) >= TYPE_PRECISION (lhs_type)
3686 || lhs_type == sizetype)))
3689 /* Allow conversion from integer to offset type and vice versa. */
3690 if ((TREE_CODE (lhs_type) == OFFSET_TYPE
3691 && TREE_CODE (rhs1_type) == INTEGER_TYPE)
3692 || (TREE_CODE (lhs_type) == INTEGER_TYPE
3693 && TREE_CODE (rhs1_type) == OFFSET_TYPE))
3696 /* Otherwise assert we are converting between types of the
3698 if (INTEGRAL_TYPE_P (lhs_type) != INTEGRAL_TYPE_P (rhs1_type))
3700 error ("invalid types in nop conversion");
3701 debug_generic_expr (lhs_type);
3702 debug_generic_expr (rhs1_type);
3709 case FIXED_CONVERT_EXPR:
3711 if (!valid_fixed_convert_types_p (lhs_type, rhs1_type)
3712 && !valid_fixed_convert_types_p (rhs1_type, lhs_type))
3714 error ("invalid types in fixed-point conversion");
3715 debug_generic_expr (lhs_type);
3716 debug_generic_expr (rhs1_type);
3725 if (!INTEGRAL_TYPE_P (rhs1_type) || !SCALAR_FLOAT_TYPE_P (lhs_type))
3727 error ("invalid types in conversion to floating point");
3728 debug_generic_expr (lhs_type);
3729 debug_generic_expr (rhs1_type);
3736 case FIX_TRUNC_EXPR:
3738 if (!INTEGRAL_TYPE_P (lhs_type) || !SCALAR_FLOAT_TYPE_P (rhs1_type))
3740 error ("invalid types in conversion to integer");
3741 debug_generic_expr (lhs_type);
3742 debug_generic_expr (rhs1_type);
3749 case VEC_UNPACK_HI_EXPR:
3750 case VEC_UNPACK_LO_EXPR:
3751 case REDUC_MAX_EXPR:
3752 case REDUC_MIN_EXPR:
3753 case REDUC_PLUS_EXPR:
3754 case VEC_UNPACK_FLOAT_HI_EXPR:
3755 case VEC_UNPACK_FLOAT_LO_EXPR:
3759 case TRUTH_NOT_EXPR:
3764 case NON_LVALUE_EXPR:
3772 /* For the remaining codes assert there is no conversion involved. */
3773 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3775 error ("non-trivial conversion in unary operation");
3776 debug_generic_expr (lhs_type);
3777 debug_generic_expr (rhs1_type);
3784 /* Verify a gimple assignment statement STMT with a binary rhs.
3785 Returns true if anything is wrong. */
3788 verify_gimple_assign_binary (gimple stmt)
3790 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3791 tree lhs = gimple_assign_lhs (stmt);
3792 tree lhs_type = TREE_TYPE (lhs);
3793 tree rhs1 = gimple_assign_rhs1 (stmt);
3794 tree rhs1_type = TREE_TYPE (rhs1);
3795 tree rhs2 = gimple_assign_rhs2 (stmt);
3796 tree rhs2_type = TREE_TYPE (rhs2);
3798 if (!is_gimple_reg (lhs)
3800 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3802 error ("non-register as LHS of binary operation");
3806 if (!is_gimple_val (rhs1)
3807 || !is_gimple_val (rhs2))
3809 error ("invalid operands in binary operation");
3813 /* First handle operations that involve different types. */
3818 if (TREE_CODE (lhs_type) != COMPLEX_TYPE
3819 || !(INTEGRAL_TYPE_P (rhs1_type)
3820 || SCALAR_FLOAT_TYPE_P (rhs1_type))
3821 || !(INTEGRAL_TYPE_P (rhs2_type)
3822 || SCALAR_FLOAT_TYPE_P (rhs2_type)))
3824 error ("type mismatch in complex expression");
3825 debug_generic_expr (lhs_type);
3826 debug_generic_expr (rhs1_type);
3827 debug_generic_expr (rhs2_type);
3839 /* Shifts and rotates are ok on integral types, fixed point
3840 types and integer vector types. */
3841 if ((!INTEGRAL_TYPE_P (rhs1_type)
3842 && !FIXED_POINT_TYPE_P (rhs1_type)
3843 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3844 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE))
3845 || (!INTEGRAL_TYPE_P (rhs2_type)
3846 /* Vector shifts of vectors are also ok. */
3847 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3848 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE
3849 && TREE_CODE (rhs2_type) == VECTOR_TYPE
3850 && TREE_CODE (TREE_TYPE (rhs2_type)) == INTEGER_TYPE))
3851 || !useless_type_conversion_p (lhs_type, rhs1_type))
3853 error ("type mismatch in shift expression");
3854 debug_generic_expr (lhs_type);
3855 debug_generic_expr (rhs1_type);
3856 debug_generic_expr (rhs2_type);
3863 case VEC_LSHIFT_EXPR:
3864 case VEC_RSHIFT_EXPR:
3866 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3867 || !(INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))
3868 || FIXED_POINT_TYPE_P (TREE_TYPE (rhs1_type))
3869 || SCALAR_FLOAT_TYPE_P (TREE_TYPE (rhs1_type)))
3870 || (!INTEGRAL_TYPE_P (rhs2_type)
3871 && (TREE_CODE (rhs2_type) != VECTOR_TYPE
3872 || !INTEGRAL_TYPE_P (TREE_TYPE (rhs2_type))))
3873 || !useless_type_conversion_p (lhs_type, rhs1_type))
3875 error ("type mismatch in vector shift expression");
3876 debug_generic_expr (lhs_type);
3877 debug_generic_expr (rhs1_type);
3878 debug_generic_expr (rhs2_type);
3881 /* For shifting a vector of floating point components we
3882 only allow shifting by a constant multiple of the element size. */
3883 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (rhs1_type))
3884 && (TREE_CODE (rhs2) != INTEGER_CST
3885 || !div_if_zero_remainder (EXACT_DIV_EXPR, rhs2,
3886 TYPE_SIZE (TREE_TYPE (rhs1_type)))))
3888 error ("non-element sized vector shift of floating point vector");
3897 /* We use regular PLUS_EXPR for vectors.
3898 ??? This just makes the checker happy and may not be what is
3900 if (TREE_CODE (lhs_type) == VECTOR_TYPE
3901 && POINTER_TYPE_P (TREE_TYPE (lhs_type)))
3903 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3904 || TREE_CODE (rhs2_type) != VECTOR_TYPE)
3906 error ("invalid non-vector operands to vector valued plus");
3909 lhs_type = TREE_TYPE (lhs_type);
3910 rhs1_type = TREE_TYPE (rhs1_type);
3911 rhs2_type = TREE_TYPE (rhs2_type);
3912 /* PLUS_EXPR is commutative, so we might end up canonicalizing
3913 the pointer to 2nd place. */
3914 if (POINTER_TYPE_P (rhs2_type))
3916 tree tem = rhs1_type;
3917 rhs1_type = rhs2_type;
3920 goto do_pointer_plus_expr_check;
3926 if (POINTER_TYPE_P (lhs_type)
3927 || POINTER_TYPE_P (rhs1_type)
3928 || POINTER_TYPE_P (rhs2_type))
3930 error ("invalid (pointer) operands to plus/minus");
3934 /* Continue with generic binary expression handling. */
3938 case POINTER_PLUS_EXPR:
3940 do_pointer_plus_expr_check:
3941 if (!POINTER_TYPE_P (rhs1_type)
3942 || !useless_type_conversion_p (lhs_type, rhs1_type)
3943 || !useless_type_conversion_p (sizetype, rhs2_type))
3945 error ("type mismatch in pointer plus expression");
3946 debug_generic_stmt (lhs_type);
3947 debug_generic_stmt (rhs1_type);
3948 debug_generic_stmt (rhs2_type);
3955 case TRUTH_ANDIF_EXPR:
3956 case TRUTH_ORIF_EXPR:
3959 case TRUTH_AND_EXPR:
3961 case TRUTH_XOR_EXPR:
3963 /* We allow any kind of integral typed argument and result. */
3964 if (!INTEGRAL_TYPE_P (rhs1_type)
3965 || !INTEGRAL_TYPE_P (rhs2_type)
3966 || !INTEGRAL_TYPE_P (lhs_type))
3968 error ("type mismatch in binary truth expression");
3969 debug_generic_expr (lhs_type);
3970 debug_generic_expr (rhs1_type);
3971 debug_generic_expr (rhs2_type);
3984 case UNORDERED_EXPR:
3992 /* Comparisons are also binary, but the result type is not
3993 connected to the operand types. */
3994 return verify_gimple_comparison (lhs_type, rhs1, rhs2);
3996 case WIDEN_SUM_EXPR:
3997 case WIDEN_MULT_EXPR:
3998 case VEC_WIDEN_MULT_HI_EXPR:
3999 case VEC_WIDEN_MULT_LO_EXPR:
4000 case VEC_PACK_TRUNC_EXPR:
4001 case VEC_PACK_SAT_EXPR:
4002 case VEC_PACK_FIX_TRUNC_EXPR:
4003 case VEC_EXTRACT_EVEN_EXPR:
4004 case VEC_EXTRACT_ODD_EXPR:
4005 case VEC_INTERLEAVE_HIGH_EXPR:
4006 case VEC_INTERLEAVE_LOW_EXPR:
4011 case TRUNC_DIV_EXPR:
4013 case FLOOR_DIV_EXPR:
4014 case ROUND_DIV_EXPR:
4015 case TRUNC_MOD_EXPR:
4017 case FLOOR_MOD_EXPR:
4018 case ROUND_MOD_EXPR:
4020 case EXACT_DIV_EXPR:
4026 /* Continue with generic binary expression handling. */
4033 if (!useless_type_conversion_p (lhs_type, rhs1_type)
4034 || !useless_type_conversion_p (lhs_type, rhs2_type))
4036 error ("type mismatch in binary expression");
4037 debug_generic_stmt (lhs_type);
4038 debug_generic_stmt (rhs1_type);
4039 debug_generic_stmt (rhs2_type);
4046 /* Verify a gimple assignment statement STMT with a single rhs.
4047 Returns true if anything is wrong. */
4050 verify_gimple_assign_single (gimple stmt)
4052 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
4053 tree lhs = gimple_assign_lhs (stmt);
4054 tree lhs_type = TREE_TYPE (lhs);
4055 tree rhs1 = gimple_assign_rhs1 (stmt);
4056 tree rhs1_type = TREE_TYPE (rhs1);
4059 if (!useless_type_conversion_p (lhs_type, rhs1_type))
4061 error ("non-trivial conversion at assignment");
4062 debug_generic_expr (lhs_type);
4063 debug_generic_expr (rhs1_type);
4067 if (handled_component_p (lhs))
4068 res |= verify_types_in_gimple_reference (lhs, true);
4070 /* Special codes we cannot handle via their class. */
4075 tree op = TREE_OPERAND (rhs1, 0);
4076 if (!is_gimple_addressable (op))
4078 error ("invalid operand in unary expression");
4082 if (!types_compatible_p (TREE_TYPE (op), TREE_TYPE (TREE_TYPE (rhs1)))
4083 && !one_pointer_to_useless_type_conversion_p (TREE_TYPE (rhs1),
4086 error ("type mismatch in address expression");
4087 debug_generic_stmt (TREE_TYPE (rhs1));
4088 debug_generic_stmt (TREE_TYPE (op));
4092 return verify_types_in_gimple_reference (op, true);
4099 case ALIGN_INDIRECT_REF:
4100 case MISALIGNED_INDIRECT_REF:
4102 case ARRAY_RANGE_REF:
4103 case VIEW_CONVERT_EXPR:
4106 case TARGET_MEM_REF:
4107 if (!is_gimple_reg (lhs)
4108 && is_gimple_reg_type (TREE_TYPE (lhs)))
4110 error ("invalid rhs for gimple memory store");
4111 debug_generic_stmt (lhs);
4112 debug_generic_stmt (rhs1);
4115 return res || verify_types_in_gimple_reference (rhs1, false);
4127 /* tcc_declaration */
4132 if (!is_gimple_reg (lhs)
4133 && !is_gimple_reg (rhs1)
4134 && is_gimple_reg_type (TREE_TYPE (lhs)))
4136 error ("invalid rhs for gimple memory store");
4137 debug_generic_stmt (lhs);
4138 debug_generic_stmt (rhs1);
4147 case WITH_SIZE_EXPR:
4148 case POLYNOMIAL_CHREC:
4151 case REALIGN_LOAD_EXPR:
4161 /* Verify the contents of a GIMPLE_ASSIGN STMT. Returns true when there
4162 is a problem, otherwise false. */
4165 verify_gimple_assign (gimple stmt)
4167 switch (gimple_assign_rhs_class (stmt))
4169 case GIMPLE_SINGLE_RHS:
4170 return verify_gimple_assign_single (stmt);
4172 case GIMPLE_UNARY_RHS:
4173 return verify_gimple_assign_unary (stmt);
4175 case GIMPLE_BINARY_RHS:
4176 return verify_gimple_assign_binary (stmt);
4183 /* Verify the contents of a GIMPLE_RETURN STMT. Returns true when there
4184 is a problem, otherwise false. */
4187 verify_gimple_return (gimple stmt)
4189 tree op = gimple_return_retval (stmt);
4190 tree restype = TREE_TYPE (TREE_TYPE (cfun->decl));
4192 /* We cannot test for present return values as we do not fix up missing
4193 return values from the original source. */
4197 if (!is_gimple_val (op)
4198 && TREE_CODE (op) != RESULT_DECL)
4200 error ("invalid operand in return statement");
4201 debug_generic_stmt (op);
4205 if (!useless_type_conversion_p (restype, TREE_TYPE (op))
4206 /* ??? With C++ we can have the situation that the result
4207 decl is a reference type while the return type is an aggregate. */
4208 && !(TREE_CODE (op) == RESULT_DECL
4209 && TREE_CODE (TREE_TYPE (op)) == REFERENCE_TYPE
4210 && useless_type_conversion_p (restype, TREE_TYPE (TREE_TYPE (op)))))
4212 error ("invalid conversion in return statement");
4213 debug_generic_stmt (restype);
4214 debug_generic_stmt (TREE_TYPE (op));
4222 /* Verify the contents of a GIMPLE_GOTO STMT. Returns true when there
4223 is a problem, otherwise false. */
4226 verify_gimple_goto (gimple stmt)
4228 tree dest = gimple_goto_dest (stmt);
4230 /* ??? We have two canonical forms of direct goto destinations, a
4231 bare LABEL_DECL and an ADDR_EXPR of a LABEL_DECL. */
4232 if (TREE_CODE (dest) != LABEL_DECL
4233 && (!is_gimple_val (dest)
4234 || !POINTER_TYPE_P (TREE_TYPE (dest))))
4236 error ("goto destination is neither a label nor a pointer");
4243 /* Verify the contents of a GIMPLE_SWITCH STMT. Returns true when there
4244 is a problem, otherwise false. */
4247 verify_gimple_switch (gimple stmt)
4249 if (!is_gimple_val (gimple_switch_index (stmt)))
4251 error ("invalid operand to switch statement");
4252 debug_generic_stmt (gimple_switch_index (stmt));
4260 /* Verify the contents of a GIMPLE_PHI. Returns true if there is a problem,
4261 and false otherwise. */
4264 verify_gimple_phi (gimple stmt)
4266 tree type = TREE_TYPE (gimple_phi_result (stmt));
4269 if (TREE_CODE (gimple_phi_result (stmt)) != SSA_NAME)
4271 error ("Invalid PHI result");
4275 for (i = 0; i < gimple_phi_num_args (stmt); i++)
4277 tree arg = gimple_phi_arg_def (stmt, i);
4278 if ((is_gimple_reg (gimple_phi_result (stmt))
4279 && !is_gimple_val (arg))
4280 || (!is_gimple_reg (gimple_phi_result (stmt))
4281 && !is_gimple_addressable (arg)))
4283 error ("Invalid PHI argument");
4284 debug_generic_stmt (arg);
4287 if (!useless_type_conversion_p (type, TREE_TYPE (arg)))
4289 error ("Incompatible types in PHI argument %u", i);
4290 debug_generic_stmt (type);
4291 debug_generic_stmt (TREE_TYPE (arg));
4300 /* Verify a gimple debug statement STMT.
4301 Returns true if anything is wrong. */
4304 verify_gimple_debug (gimple stmt ATTRIBUTE_UNUSED)
4306 /* There isn't much that could be wrong in a gimple debug stmt. A
4307 gimple debug bind stmt, for example, maps a tree, that's usually
4308 a VAR_DECL or a PARM_DECL, but that could also be some scalarized
4309 component or member of an aggregate type, to another tree, that
4310 can be an arbitrary expression. These stmts expand into debug
4311 insns, and are converted to debug notes by var-tracking.c. */
4316 /* Verify the GIMPLE statement STMT. Returns true if there is an
4317 error, otherwise false. */
4320 verify_types_in_gimple_stmt (gimple stmt)
4322 switch (gimple_code (stmt))
4325 return verify_gimple_assign (stmt);
4328 return TREE_CODE (gimple_label_label (stmt)) != LABEL_DECL;
4331 return verify_gimple_call (stmt);
4334 return verify_gimple_comparison (boolean_type_node,
4335 gimple_cond_lhs (stmt),
4336 gimple_cond_rhs (stmt));
4339 return verify_gimple_goto (stmt);
4342 return verify_gimple_switch (stmt);
4345 return verify_gimple_return (stmt);
4351 return verify_gimple_phi (stmt);
4353 /* Tuples that do not have tree operands. */
4355 case GIMPLE_PREDICT:
4357 case GIMPLE_EH_DISPATCH:
4358 case GIMPLE_EH_MUST_NOT_THROW:
4362 /* OpenMP directives are validated by the FE and never operated
4363 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4364 non-gimple expressions when the main index variable has had
4365 its address taken. This does not affect the loop itself
4366 because the header of an GIMPLE_OMP_FOR is merely used to determine
4367 how to setup the parallel iteration. */
4371 return verify_gimple_debug (stmt);
4378 /* Verify the GIMPLE statements inside the sequence STMTS. */
4381 verify_types_in_gimple_seq_2 (gimple_seq stmts)
4383 gimple_stmt_iterator ittr;
4386 for (ittr = gsi_start (stmts); !gsi_end_p (ittr); gsi_next (&ittr))
4388 gimple stmt = gsi_stmt (ittr);
4390 switch (gimple_code (stmt))
4393 err |= verify_types_in_gimple_seq_2 (gimple_bind_body (stmt));
4397 err |= verify_types_in_gimple_seq_2 (gimple_try_eval (stmt));
4398 err |= verify_types_in_gimple_seq_2 (gimple_try_cleanup (stmt));
4401 case GIMPLE_EH_FILTER:
4402 err |= verify_types_in_gimple_seq_2 (gimple_eh_filter_failure (stmt));
4406 err |= verify_types_in_gimple_seq_2 (gimple_catch_handler (stmt));
4411 bool err2 = verify_types_in_gimple_stmt (stmt);
4413 debug_gimple_stmt (stmt);
4423 /* Verify the GIMPLE statements inside the statement list STMTS. */
4426 verify_types_in_gimple_seq (gimple_seq stmts)
4428 if (verify_types_in_gimple_seq_2 (stmts))
4429 internal_error ("verify_gimple failed");
4433 /* Verify STMT, return true if STMT is not in GIMPLE form.
4434 TODO: Implement type checking. */
4437 verify_stmt (gimple_stmt_iterator *gsi)
4440 struct walk_stmt_info wi;
4441 bool last_in_block = gsi_one_before_end_p (*gsi);
4442 gimple stmt = gsi_stmt (*gsi);
4445 if (is_gimple_omp (stmt))
4447 /* OpenMP directives are validated by the FE and never operated
4448 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4449 non-gimple expressions when the main index variable has had
4450 its address taken. This does not affect the loop itself
4451 because the header of an GIMPLE_OMP_FOR is merely used to determine
4452 how to setup the parallel iteration. */
4456 /* FIXME. The C frontend passes unpromoted arguments in case it
4457 didn't see a function declaration before the call. */
4458 if (is_gimple_call (stmt))
4462 if (!is_gimple_call_addr (gimple_call_fn (stmt)))
4464 error ("invalid function in call statement");
4468 decl = gimple_call_fndecl (stmt);
4470 && TREE_CODE (decl) == FUNCTION_DECL
4471 && DECL_LOOPING_CONST_OR_PURE_P (decl)
4472 && (!DECL_PURE_P (decl))
4473 && (!TREE_READONLY (decl)))
4475 error ("invalid pure const state for function");
4480 if (is_gimple_debug (stmt))
4483 memset (&wi, 0, sizeof (wi));
4484 addr = walk_gimple_op (gsi_stmt (*gsi), verify_expr, &wi);
4487 debug_generic_expr (addr);
4488 inform (gimple_location (gsi_stmt (*gsi)), "in statement");
4489 debug_gimple_stmt (stmt);
4493 /* If the statement is marked as part of an EH region, then it is
4494 expected that the statement could throw. Verify that when we
4495 have optimizations that simplify statements such that we prove
4496 that they cannot throw, that we update other data structures
4498 lp_nr = lookup_stmt_eh_lp (stmt);
4501 if (!stmt_could_throw_p (stmt))
4503 /* During IPA passes, ipa-pure-const sets nothrow flags on calls
4504 and they are updated on statements only after fixup_cfg
4505 is executed at beggining of expansion stage. */
4506 if (cgraph_state != CGRAPH_STATE_IPA_SSA)
4508 error ("statement marked for throw, but doesn%'t");
4512 else if (lp_nr > 0 && !last_in_block && stmt_can_throw_internal (stmt))
4514 error ("statement marked for throw in middle of block");
4522 debug_gimple_stmt (stmt);
4527 /* Return true when the T can be shared. */
4530 tree_node_can_be_shared (tree t)
4532 if (IS_TYPE_OR_DECL_P (t)
4533 || is_gimple_min_invariant (t)
4534 || TREE_CODE (t) == SSA_NAME
4535 || t == error_mark_node
4536 || TREE_CODE (t) == IDENTIFIER_NODE)
4539 if (TREE_CODE (t) == CASE_LABEL_EXPR)
4542 while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4543 && is_gimple_min_invariant (TREE_OPERAND (t, 1)))
4544 || TREE_CODE (t) == COMPONENT_REF
4545 || TREE_CODE (t) == REALPART_EXPR
4546 || TREE_CODE (t) == IMAGPART_EXPR)
4547 t = TREE_OPERAND (t, 0);
4556 /* Called via walk_gimple_stmt. Verify tree sharing. */
4559 verify_node_sharing (tree *tp, int *walk_subtrees, void *data)
4561 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
4562 struct pointer_set_t *visited = (struct pointer_set_t *) wi->info;
4564 if (tree_node_can_be_shared (*tp))
4566 *walk_subtrees = false;
4570 if (pointer_set_insert (visited, *tp))
4577 static bool eh_error_found;
4579 verify_eh_throw_stmt_node (void **slot, void *data)
4581 struct throw_stmt_node *node = (struct throw_stmt_node *)*slot;
4582 struct pointer_set_t *visited = (struct pointer_set_t *) data;
4584 if (!pointer_set_contains (visited, node->stmt))
4586 error ("Dead STMT in EH table");
4587 debug_gimple_stmt (node->stmt);
4588 eh_error_found = true;
4594 /* Verify the GIMPLE statements in every basic block. */
4600 gimple_stmt_iterator gsi;
4602 struct pointer_set_t *visited, *visited_stmts;
4604 struct walk_stmt_info wi;
4606 timevar_push (TV_TREE_STMT_VERIFY);
4607 visited = pointer_set_create ();
4608 visited_stmts = pointer_set_create ();
4610 memset (&wi, 0, sizeof (wi));
4611 wi.info = (void *) visited;
4618 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4620 phi = gsi_stmt (gsi);
4621 pointer_set_insert (visited_stmts, phi);
4622 if (gimple_bb (phi) != bb)
4624 error ("gimple_bb (phi) is set to a wrong basic block");
4628 for (i = 0; i < gimple_phi_num_args (phi); i++)
4630 tree t = gimple_phi_arg_def (phi, i);
4635 error ("missing PHI def");
4636 debug_gimple_stmt (phi);
4640 /* Addressable variables do have SSA_NAMEs but they
4641 are not considered gimple values. */
4642 else if (TREE_CODE (t) != SSA_NAME
4643 && TREE_CODE (t) != FUNCTION_DECL
4644 && !is_gimple_min_invariant (t))
4646 error ("PHI argument is not a GIMPLE value");
4647 debug_gimple_stmt (phi);
4648 debug_generic_expr (t);
4652 addr = walk_tree (&t, verify_node_sharing, visited, NULL);
4655 error ("incorrect sharing of tree nodes");
4656 debug_gimple_stmt (phi);
4657 debug_generic_expr (addr);
4662 #ifdef ENABLE_TYPES_CHECKING
4663 if (verify_gimple_phi (phi))
4665 debug_gimple_stmt (phi);
4671 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); )
4673 gimple stmt = gsi_stmt (gsi);
4675 if (gimple_code (stmt) == GIMPLE_WITH_CLEANUP_EXPR
4676 || gimple_code (stmt) == GIMPLE_BIND)
4678 error ("invalid GIMPLE statement");
4679 debug_gimple_stmt (stmt);
4683 pointer_set_insert (visited_stmts, stmt);
4685 if (gimple_bb (stmt) != bb)
4687 error ("gimple_bb (stmt) is set to a wrong basic block");
4688 debug_gimple_stmt (stmt);
4692 if (gimple_code (stmt) == GIMPLE_LABEL)
4694 tree decl = gimple_label_label (stmt);
4695 int uid = LABEL_DECL_UID (decl);
4698 || VEC_index (basic_block, label_to_block_map, uid) != bb)
4700 error ("incorrect entry in label_to_block_map");
4704 uid = EH_LANDING_PAD_NR (decl);
4707 eh_landing_pad lp = get_eh_landing_pad_from_number (uid);
4708 if (decl != lp->post_landing_pad)
4710 error ("incorrect setting of landing pad number");
4716 err |= verify_stmt (&gsi);
4718 #ifdef ENABLE_TYPES_CHECKING
4719 if (verify_types_in_gimple_stmt (gsi_stmt (gsi)))
4721 debug_gimple_stmt (stmt);
4725 addr = walk_gimple_op (gsi_stmt (gsi), verify_node_sharing, &wi);
4728 error ("incorrect sharing of tree nodes");
4729 debug_gimple_stmt (stmt);
4730 debug_generic_expr (addr);
4737 eh_error_found = false;
4738 if (get_eh_throw_stmt_table (cfun))
4739 htab_traverse (get_eh_throw_stmt_table (cfun),
4740 verify_eh_throw_stmt_node,
4743 if (err | eh_error_found)
4744 internal_error ("verify_stmts failed");
4746 pointer_set_destroy (visited);
4747 pointer_set_destroy (visited_stmts);
4748 verify_histograms ();
4749 timevar_pop (TV_TREE_STMT_VERIFY);
4753 /* Verifies that the flow information is OK. */
4756 gimple_verify_flow_info (void)
4760 gimple_stmt_iterator gsi;
4765 if (ENTRY_BLOCK_PTR->il.gimple)
4767 error ("ENTRY_BLOCK has IL associated with it");
4771 if (EXIT_BLOCK_PTR->il.gimple)
4773 error ("EXIT_BLOCK has IL associated with it");
4777 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4778 if (e->flags & EDGE_FALLTHRU)
4780 error ("fallthru to exit from bb %d", e->src->index);
4786 bool found_ctrl_stmt = false;
4790 /* Skip labels on the start of basic block. */
4791 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4794 gimple prev_stmt = stmt;
4796 stmt = gsi_stmt (gsi);
4798 if (gimple_code (stmt) != GIMPLE_LABEL)
4801 label = gimple_label_label (stmt);
4802 if (prev_stmt && DECL_NONLOCAL (label))
4804 error ("nonlocal label ");
4805 print_generic_expr (stderr, label, 0);
4806 fprintf (stderr, " is not first in a sequence of labels in bb %d",
4811 if (label_to_block (label) != bb)
4814 print_generic_expr (stderr, label, 0);
4815 fprintf (stderr, " to block does not match in bb %d",
4820 if (decl_function_context (label) != current_function_decl)
4823 print_generic_expr (stderr, label, 0);
4824 fprintf (stderr, " has incorrect context in bb %d",
4830 /* Verify that body of basic block BB is free of control flow. */
4831 for (; !gsi_end_p (gsi); gsi_next (&gsi))
4833 gimple stmt = gsi_stmt (gsi);
4835 if (found_ctrl_stmt)
4837 error ("control flow in the middle of basic block %d",
4842 if (stmt_ends_bb_p (stmt))
4843 found_ctrl_stmt = true;
4845 if (gimple_code (stmt) == GIMPLE_LABEL)
4848 print_generic_expr (stderr, gimple_label_label (stmt), 0);
4849 fprintf (stderr, " in the middle of basic block %d", bb->index);
4854 gsi = gsi_last_bb (bb);
4855 if (gsi_end_p (gsi))
4858 stmt = gsi_stmt (gsi);
4860 if (gimple_code (stmt) == GIMPLE_LABEL)
4863 err |= verify_eh_edges (stmt);
4865 if (is_ctrl_stmt (stmt))
4867 FOR_EACH_EDGE (e, ei, bb->succs)
4868 if (e->flags & EDGE_FALLTHRU)
4870 error ("fallthru edge after a control statement in bb %d",
4876 if (gimple_code (stmt) != GIMPLE_COND)
4878 /* Verify that there are no edges with EDGE_TRUE/FALSE_FLAG set
4879 after anything else but if statement. */
4880 FOR_EACH_EDGE (e, ei, bb->succs)
4881 if (e->flags & (EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))
4883 error ("true/false edge after a non-GIMPLE_COND in bb %d",
4889 switch (gimple_code (stmt))
4896 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
4900 || !(true_edge->flags & EDGE_TRUE_VALUE)
4901 || !(false_edge->flags & EDGE_FALSE_VALUE)
4902 || (true_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4903 || (false_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4904 || EDGE_COUNT (bb->succs) >= 3)
4906 error ("wrong outgoing edge flags at end of bb %d",
4914 if (simple_goto_p (stmt))
4916 error ("explicit goto at end of bb %d", bb->index);
4921 /* FIXME. We should double check that the labels in the
4922 destination blocks have their address taken. */
4923 FOR_EACH_EDGE (e, ei, bb->succs)
4924 if ((e->flags & (EDGE_FALLTHRU | EDGE_TRUE_VALUE
4925 | EDGE_FALSE_VALUE))
4926 || !(e->flags & EDGE_ABNORMAL))
4928 error ("wrong outgoing edge flags at end of bb %d",
4936 if (!single_succ_p (bb)
4937 || (single_succ_edge (bb)->flags
4938 & (EDGE_FALLTHRU | EDGE_ABNORMAL
4939 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4941 error ("wrong outgoing edge flags at end of bb %d", bb->index);
4944 if (single_succ (bb) != EXIT_BLOCK_PTR)
4946 error ("return edge does not point to exit in bb %d",
4958 n = gimple_switch_num_labels (stmt);
4960 /* Mark all the destination basic blocks. */
4961 for (i = 0; i < n; ++i)
4963 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4964 basic_block label_bb = label_to_block (lab);
4965 gcc_assert (!label_bb->aux || label_bb->aux == (void *)1);
4966 label_bb->aux = (void *)1;
4969 /* Verify that the case labels are sorted. */
4970 prev = gimple_switch_label (stmt, 0);
4971 for (i = 1; i < n; ++i)
4973 tree c = gimple_switch_label (stmt, i);
4976 error ("found default case not at the start of "
4982 && !tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c)))
4984 error ("case labels not sorted: ");
4985 print_generic_expr (stderr, prev, 0);
4986 fprintf (stderr," is greater than ");
4987 print_generic_expr (stderr, c, 0);
4988 fprintf (stderr," but comes before it.\n");
4993 /* VRP will remove the default case if it can prove it will
4994 never be executed. So do not verify there always exists
4995 a default case here. */
4997 FOR_EACH_EDGE (e, ei, bb->succs)
5001 error ("extra outgoing edge %d->%d",
5002 bb->index, e->dest->index);
5006 e->dest->aux = (void *)2;
5007 if ((e->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL
5008 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
5010 error ("wrong outgoing edge flags at end of bb %d",
5016 /* Check that we have all of them. */
5017 for (i = 0; i < n; ++i)
5019 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
5020 basic_block label_bb = label_to_block (lab);
5022 if (label_bb->aux != (void *)2)
5024 error ("missing edge %i->%i", bb->index, label_bb->index);
5029 FOR_EACH_EDGE (e, ei, bb->succs)
5030 e->dest->aux = (void *)0;
5034 case GIMPLE_EH_DISPATCH:
5035 err |= verify_eh_dispatch_edge (stmt);
5043 if (dom_info_state (CDI_DOMINATORS) >= DOM_NO_FAST_QUERY)
5044 verify_dominators (CDI_DOMINATORS);
5050 /* Updates phi nodes after creating a forwarder block joined
5051 by edge FALLTHRU. */
5054 gimple_make_forwarder_block (edge fallthru)
5058 basic_block dummy, bb;
5060 gimple_stmt_iterator gsi;
5062 dummy = fallthru->src;
5063 bb = fallthru->dest;
5065 if (single_pred_p (bb))
5068 /* If we redirected a branch we must create new PHI nodes at the
5070 for (gsi = gsi_start_phis (dummy); !gsi_end_p (gsi); gsi_next (&gsi))
5072 gimple phi, new_phi;
5074 phi = gsi_stmt (gsi);
5075 var = gimple_phi_result (phi);
5076 new_phi = create_phi_node (var, bb);
5077 SSA_NAME_DEF_STMT (var) = new_phi;
5078 gimple_phi_set_result (phi, make_ssa_name (SSA_NAME_VAR (var), phi));
5079 add_phi_arg (new_phi, gimple_phi_result (phi), fallthru,
5083 /* Add the arguments we have stored on edges. */
5084 FOR_EACH_EDGE (e, ei, bb->preds)
5089 flush_pending_stmts (e);
5094 /* Return a non-special label in the head of basic block BLOCK.
5095 Create one if it doesn't exist. */
5098 gimple_block_label (basic_block bb)
5100 gimple_stmt_iterator i, s = gsi_start_bb (bb);
5105 for (i = s; !gsi_end_p (i); first = false, gsi_next (&i))
5107 stmt = gsi_stmt (i);
5108 if (gimple_code (stmt) != GIMPLE_LABEL)
5110 label = gimple_label_label (stmt);
5111 if (!DECL_NONLOCAL (label))
5114 gsi_move_before (&i, &s);
5119 label = create_artificial_label (UNKNOWN_LOCATION);
5120 stmt = gimple_build_label (label);
5121 gsi_insert_before (&s, stmt, GSI_NEW_STMT);
5126 /* Attempt to perform edge redirection by replacing a possibly complex
5127 jump instruction by a goto or by removing the jump completely.
5128 This can apply only if all edges now point to the same block. The
5129 parameters and return values are equivalent to
5130 redirect_edge_and_branch. */
5133 gimple_try_redirect_by_replacing_jump (edge e, basic_block target)
5135 basic_block src = e->src;
5136 gimple_stmt_iterator i;
5139 /* We can replace or remove a complex jump only when we have exactly
5141 if (EDGE_COUNT (src->succs) != 2
5142 /* Verify that all targets will be TARGET. Specifically, the
5143 edge that is not E must also go to TARGET. */
5144 || EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)
5147 i = gsi_last_bb (src);
5151 stmt = gsi_stmt (i);
5153 if (gimple_code (stmt) == GIMPLE_COND || gimple_code (stmt) == GIMPLE_SWITCH)
5155 gsi_remove (&i, true);
5156 e = ssa_redirect_edge (e, target);
5157 e->flags = EDGE_FALLTHRU;
5165 /* Redirect E to DEST. Return NULL on failure. Otherwise, return the
5166 edge representing the redirected branch. */
5169 gimple_redirect_edge_and_branch (edge e, basic_block dest)
5171 basic_block bb = e->src;
5172 gimple_stmt_iterator gsi;
5176 if (e->flags & EDGE_ABNORMAL)
5179 if (e->dest == dest)
5182 if (e->flags & EDGE_EH)
5183 return redirect_eh_edge (e, dest);
5185 if (e->src != ENTRY_BLOCK_PTR)
5187 ret = gimple_try_redirect_by_replacing_jump (e, dest);
5192 gsi = gsi_last_bb (bb);
5193 stmt = gsi_end_p (gsi) ? NULL : gsi_stmt (gsi);
5195 switch (stmt ? gimple_code (stmt) : GIMPLE_ERROR_MARK)
5198 /* For COND_EXPR, we only need to redirect the edge. */
5202 /* No non-abnormal edges should lead from a non-simple goto, and
5203 simple ones should be represented implicitly. */
5208 tree label = gimple_block_label (dest);
5209 tree cases = get_cases_for_edge (e, stmt);
5211 /* If we have a list of cases associated with E, then use it
5212 as it's a lot faster than walking the entire case vector. */
5215 edge e2 = find_edge (e->src, dest);
5222 CASE_LABEL (cases) = label;
5223 cases = TREE_CHAIN (cases);
5226 /* If there was already an edge in the CFG, then we need
5227 to move all the cases associated with E to E2. */
5230 tree cases2 = get_cases_for_edge (e2, stmt);
5232 TREE_CHAIN (last) = TREE_CHAIN (cases2);
5233 TREE_CHAIN (cases2) = first;
5238 size_t i, n = gimple_switch_num_labels (stmt);
5240 for (i = 0; i < n; i++)
5242 tree elt = gimple_switch_label (stmt, i);
5243 if (label_to_block (CASE_LABEL (elt)) == e->dest)
5244 CASE_LABEL (elt) = label;
5252 int i, n = gimple_asm_nlabels (stmt);
5253 tree label = gimple_block_label (dest);
5255 for (i = 0; i < n; ++i)
5257 tree cons = gimple_asm_label_op (stmt, i);
5258 if (label_to_block (TREE_VALUE (cons)) == e->dest)
5259 TREE_VALUE (cons) = label;
5265 gsi_remove (&gsi, true);
5266 e->flags |= EDGE_FALLTHRU;
5269 case GIMPLE_OMP_RETURN:
5270 case GIMPLE_OMP_CONTINUE:
5271 case GIMPLE_OMP_SECTIONS_SWITCH:
5272 case GIMPLE_OMP_FOR:
5273 /* The edges from OMP constructs can be simply redirected. */
5276 case GIMPLE_EH_DISPATCH:
5277 if (!(e->flags & EDGE_FALLTHRU))
5278 redirect_eh_dispatch_edge (stmt, e, dest);
5282 /* Otherwise it must be a fallthru edge, and we don't need to
5283 do anything besides redirecting it. */
5284 gcc_assert (e->flags & EDGE_FALLTHRU);
5288 /* Update/insert PHI nodes as necessary. */
5290 /* Now update the edges in the CFG. */
5291 e = ssa_redirect_edge (e, dest);
5296 /* Returns true if it is possible to remove edge E by redirecting
5297 it to the destination of the other edge from E->src. */
5300 gimple_can_remove_branch_p (const_edge e)
5302 if (e->flags & (EDGE_ABNORMAL | EDGE_EH))
5308 /* Simple wrapper, as we can always redirect fallthru edges. */
5311 gimple_redirect_edge_and_branch_force (edge e, basic_block dest)
5313 e = gimple_redirect_edge_and_branch (e, dest);
5320 /* Splits basic block BB after statement STMT (but at least after the
5321 labels). If STMT is NULL, BB is split just after the labels. */
5324 gimple_split_block (basic_block bb, void *stmt)
5326 gimple_stmt_iterator gsi;
5327 gimple_stmt_iterator gsi_tgt;
5334 new_bb = create_empty_bb (bb);
5336 /* Redirect the outgoing edges. */
5337 new_bb->succs = bb->succs;
5339 FOR_EACH_EDGE (e, ei, new_bb->succs)
5342 if (stmt && gimple_code ((gimple) stmt) == GIMPLE_LABEL)
5345 /* Move everything from GSI to the new basic block. */
5346 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5348 act = gsi_stmt (gsi);
5349 if (gimple_code (act) == GIMPLE_LABEL)
5362 if (gsi_end_p (gsi))
5365 /* Split the statement list - avoid re-creating new containers as this
5366 brings ugly quadratic memory consumption in the inliner.
5367 (We are still quadratic since we need to update stmt BB pointers,
5369 list = gsi_split_seq_before (&gsi);
5370 set_bb_seq (new_bb, list);
5371 for (gsi_tgt = gsi_start (list);
5372 !gsi_end_p (gsi_tgt); gsi_next (&gsi_tgt))
5373 gimple_set_bb (gsi_stmt (gsi_tgt), new_bb);
5379 /* Moves basic block BB after block AFTER. */
5382 gimple_move_block_after (basic_block bb, basic_block after)
5384 if (bb->prev_bb == after)
5388 link_block (bb, after);
5394 /* Return true if basic_block can be duplicated. */
5397 gimple_can_duplicate_bb_p (const_basic_block bb ATTRIBUTE_UNUSED)
5402 /* Create a duplicate of the basic block BB. NOTE: This does not
5403 preserve SSA form. */
5406 gimple_duplicate_bb (basic_block bb)
5409 gimple_stmt_iterator gsi, gsi_tgt;
5410 gimple_seq phis = phi_nodes (bb);
5411 gimple phi, stmt, copy;
5413 new_bb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb);
5415 /* Copy the PHI nodes. We ignore PHI node arguments here because
5416 the incoming edges have not been setup yet. */
5417 for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
5419 phi = gsi_stmt (gsi);
5420 copy = create_phi_node (gimple_phi_result (phi), new_bb);
5421 create_new_def_for (gimple_phi_result (copy), copy,
5422 gimple_phi_result_ptr (copy));
5425 gsi_tgt = gsi_start_bb (new_bb);
5426 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5428 def_operand_p def_p;
5429 ssa_op_iter op_iter;
5431 stmt = gsi_stmt (gsi);
5432 if (gimple_code (stmt) == GIMPLE_LABEL)
5435 /* Create a new copy of STMT and duplicate STMT's virtual
5437 copy = gimple_copy (stmt);
5438 gsi_insert_after (&gsi_tgt, copy, GSI_NEW_STMT);
5440 maybe_duplicate_eh_stmt (copy, stmt);
5441 gimple_duplicate_stmt_histograms (cfun, copy, cfun, stmt);
5443 /* Create new names for all the definitions created by COPY and
5444 add replacement mappings for each new name. */
5445 FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS)
5446 create_new_def_for (DEF_FROM_PTR (def_p), copy, def_p);
5452 /* Adds phi node arguments for edge E_COPY after basic block duplication. */
5455 add_phi_args_after_copy_edge (edge e_copy)
5457 basic_block bb, bb_copy = e_copy->src, dest;
5460 gimple phi, phi_copy;
5462 gimple_stmt_iterator psi, psi_copy;
5464 if (gimple_seq_empty_p (phi_nodes (e_copy->dest)))
5467 bb = bb_copy->flags & BB_DUPLICATED ? get_bb_original (bb_copy) : bb_copy;
5469 if (e_copy->dest->flags & BB_DUPLICATED)
5470 dest = get_bb_original (e_copy->dest);
5472 dest = e_copy->dest;
5474 e = find_edge (bb, dest);
5477 /* During loop unrolling the target of the latch edge is copied.
5478 In this case we are not looking for edge to dest, but to
5479 duplicated block whose original was dest. */
5480 FOR_EACH_EDGE (e, ei, bb->succs)
5482 if ((e->dest->flags & BB_DUPLICATED)
5483 && get_bb_original (e->dest) == dest)
5487 gcc_assert (e != NULL);
5490 for (psi = gsi_start_phis (e->dest),
5491 psi_copy = gsi_start_phis (e_copy->dest);
5493 gsi_next (&psi), gsi_next (&psi_copy))
5495 phi = gsi_stmt (psi);
5496 phi_copy = gsi_stmt (psi_copy);
5497 def = PHI_ARG_DEF_FROM_EDGE (phi, e);
5498 add_phi_arg (phi_copy, def, e_copy,
5499 gimple_phi_arg_location_from_edge (phi, e));
5504 /* Basic block BB_COPY was created by code duplication. Add phi node
5505 arguments for edges going out of BB_COPY. The blocks that were
5506 duplicated have BB_DUPLICATED set. */
5509 add_phi_args_after_copy_bb (basic_block bb_copy)
5514 FOR_EACH_EDGE (e_copy, ei, bb_copy->succs)
5516 add_phi_args_after_copy_edge (e_copy);
5520 /* Blocks in REGION_COPY array of length N_REGION were created by
5521 duplication of basic blocks. Add phi node arguments for edges
5522 going from these blocks. If E_COPY is not NULL, also add
5523 phi node arguments for its destination.*/
5526 add_phi_args_after_copy (basic_block *region_copy, unsigned n_region,
5531 for (i = 0; i < n_region; i++)
5532 region_copy[i]->flags |= BB_DUPLICATED;
5534 for (i = 0; i < n_region; i++)
5535 add_phi_args_after_copy_bb (region_copy[i]);
5537 add_phi_args_after_copy_edge (e_copy);
5539 for (i = 0; i < n_region; i++)
5540 region_copy[i]->flags &= ~BB_DUPLICATED;
5543 /* Duplicates a REGION (set of N_REGION basic blocks) with just a single
5544 important exit edge EXIT. By important we mean that no SSA name defined
5545 inside region is live over the other exit edges of the region. All entry
5546 edges to the region must go to ENTRY->dest. The edge ENTRY is redirected
5547 to the duplicate of the region. SSA form, dominance and loop information
5548 is updated. The new basic blocks are stored to REGION_COPY in the same
5549 order as they had in REGION, provided that REGION_COPY is not NULL.
5550 The function returns false if it is unable to copy the region,
5554 gimple_duplicate_sese_region (edge entry, edge exit,
5555 basic_block *region, unsigned n_region,
5556 basic_block *region_copy)
5559 bool free_region_copy = false, copying_header = false;
5560 struct loop *loop = entry->dest->loop_father;
5562 VEC (basic_block, heap) *doms;
5564 int total_freq = 0, entry_freq = 0;
5565 gcov_type total_count = 0, entry_count = 0;
5567 if (!can_copy_bbs_p (region, n_region))
5570 /* Some sanity checking. Note that we do not check for all possible
5571 missuses of the functions. I.e. if you ask to copy something weird,
5572 it will work, but the state of structures probably will not be
5574 for (i = 0; i < n_region; i++)
5576 /* We do not handle subloops, i.e. all the blocks must belong to the
5578 if (region[i]->loop_father != loop)
5581 if (region[i] != entry->dest
5582 && region[i] == loop->header)
5586 set_loop_copy (loop, loop);
5588 /* In case the function is used for loop header copying (which is the primary
5589 use), ensure that EXIT and its copy will be new latch and entry edges. */
5590 if (loop->header == entry->dest)
5592 copying_header = true;
5593 set_loop_copy (loop, loop_outer (loop));
5595 if (!dominated_by_p (CDI_DOMINATORS, loop->latch, exit->src))
5598 for (i = 0; i < n_region; i++)
5599 if (region[i] != exit->src
5600 && dominated_by_p (CDI_DOMINATORS, region[i], exit->src))
5606 region_copy = XNEWVEC (basic_block, n_region);
5607 free_region_copy = true;
5610 gcc_assert (!need_ssa_update_p (cfun));
5612 /* Record blocks outside the region that are dominated by something
5615 initialize_original_copy_tables ();
5617 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5619 if (entry->dest->count)
5621 total_count = entry->dest->count;
5622 entry_count = entry->count;
5623 /* Fix up corner cases, to avoid division by zero or creation of negative
5625 if (entry_count > total_count)
5626 entry_count = total_count;
5630 total_freq = entry->dest->frequency;
5631 entry_freq = EDGE_FREQUENCY (entry);
5632 /* Fix up corner cases, to avoid division by zero or creation of negative
5634 if (total_freq == 0)
5636 else if (entry_freq > total_freq)
5637 entry_freq = total_freq;
5640 copy_bbs (region, n_region, region_copy, &exit, 1, &exit_copy, loop,
5641 split_edge_bb_loc (entry));
5644 scale_bbs_frequencies_gcov_type (region, n_region,
5645 total_count - entry_count,
5647 scale_bbs_frequencies_gcov_type (region_copy, n_region, entry_count,
5652 scale_bbs_frequencies_int (region, n_region, total_freq - entry_freq,
5654 scale_bbs_frequencies_int (region_copy, n_region, entry_freq, total_freq);
5659 loop->header = exit->dest;
5660 loop->latch = exit->src;
5663 /* Redirect the entry and add the phi node arguments. */
5664 redirected = redirect_edge_and_branch (entry, get_bb_copy (entry->dest));
5665 gcc_assert (redirected != NULL);
5666 flush_pending_stmts (entry);
5668 /* Concerning updating of dominators: We must recount dominators
5669 for entry block and its copy. Anything that is outside of the
5670 region, but was dominated by something inside needs recounting as
5672 set_immediate_dominator (CDI_DOMINATORS, entry->dest, entry->src);
5673 VEC_safe_push (basic_block, heap, doms, get_bb_original (entry->dest));
5674 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5675 VEC_free (basic_block, heap, doms);
5677 /* Add the other PHI node arguments. */
5678 add_phi_args_after_copy (region_copy, n_region, NULL);
5680 /* Update the SSA web. */
5681 update_ssa (TODO_update_ssa);
5683 if (free_region_copy)
5686 free_original_copy_tables ();
5690 /* Duplicates REGION consisting of N_REGION blocks. The new blocks
5691 are stored to REGION_COPY in the same order in that they appear
5692 in REGION, if REGION_COPY is not NULL. ENTRY is the entry to
5693 the region, EXIT an exit from it. The condition guarding EXIT
5694 is moved to ENTRY. Returns true if duplication succeeds, false
5720 gimple_duplicate_sese_tail (edge entry ATTRIBUTE_UNUSED, edge exit ATTRIBUTE_UNUSED,
5721 basic_block *region ATTRIBUTE_UNUSED, unsigned n_region ATTRIBUTE_UNUSED,
5722 basic_block *region_copy ATTRIBUTE_UNUSED)
5725 bool free_region_copy = false;
5726 struct loop *loop = exit->dest->loop_father;
5727 struct loop *orig_loop = entry->dest->loop_father;
5728 basic_block switch_bb, entry_bb, nentry_bb;
5729 VEC (basic_block, heap) *doms;
5730 int total_freq = 0, exit_freq = 0;
5731 gcov_type total_count = 0, exit_count = 0;
5732 edge exits[2], nexits[2], e;
5733 gimple_stmt_iterator gsi;
5737 gcc_assert (EDGE_COUNT (exit->src->succs) == 2);
5739 exits[1] = EDGE_SUCC (exit->src, EDGE_SUCC (exit->src, 0) == exit);
5741 if (!can_copy_bbs_p (region, n_region))
5744 /* Some sanity checking. Note that we do not check for all possible
5745 missuses of the functions. I.e. if you ask to copy something weird
5746 (e.g., in the example, if there is a jump from inside to the middle
5747 of some_code, or come_code defines some of the values used in cond)
5748 it will work, but the resulting code will not be correct. */
5749 for (i = 0; i < n_region; i++)
5751 /* We do not handle subloops, i.e. all the blocks must belong to the
5753 if (region[i]->loop_father != orig_loop)
5756 if (region[i] == orig_loop->latch)
5760 initialize_original_copy_tables ();
5761 set_loop_copy (orig_loop, loop);
5765 region_copy = XNEWVEC (basic_block, n_region);
5766 free_region_copy = true;
5769 gcc_assert (!need_ssa_update_p (cfun));
5771 /* Record blocks outside the region that are dominated by something
5773 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5775 if (exit->src->count)
5777 total_count = exit->src->count;
5778 exit_count = exit->count;
5779 /* Fix up corner cases, to avoid division by zero or creation of negative
5781 if (exit_count > total_count)
5782 exit_count = total_count;
5786 total_freq = exit->src->frequency;
5787 exit_freq = EDGE_FREQUENCY (exit);
5788 /* Fix up corner cases, to avoid division by zero or creation of negative
5790 if (total_freq == 0)
5792 if (exit_freq > total_freq)
5793 exit_freq = total_freq;
5796 copy_bbs (region, n_region, region_copy, exits, 2, nexits, orig_loop,
5797 split_edge_bb_loc (exit));
5800 scale_bbs_frequencies_gcov_type (region, n_region,
5801 total_count - exit_count,
5803 scale_bbs_frequencies_gcov_type (region_copy, n_region, exit_count,
5808 scale_bbs_frequencies_int (region, n_region, total_freq - exit_freq,
5810 scale_bbs_frequencies_int (region_copy, n_region, exit_freq, total_freq);
5813 /* Create the switch block, and put the exit condition to it. */
5814 entry_bb = entry->dest;
5815 nentry_bb = get_bb_copy (entry_bb);
5816 if (!last_stmt (entry->src)
5817 || !stmt_ends_bb_p (last_stmt (entry->src)))
5818 switch_bb = entry->src;
5820 switch_bb = split_edge (entry);
5821 set_immediate_dominator (CDI_DOMINATORS, nentry_bb, switch_bb);
5823 gsi = gsi_last_bb (switch_bb);
5824 cond_stmt = last_stmt (exit->src);
5825 gcc_assert (gimple_code (cond_stmt) == GIMPLE_COND);
5826 cond_stmt = gimple_copy (cond_stmt);
5827 gimple_cond_set_lhs (cond_stmt, unshare_expr (gimple_cond_lhs (cond_stmt)));
5828 gimple_cond_set_rhs (cond_stmt, unshare_expr (gimple_cond_rhs (cond_stmt)));
5829 gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT);
5831 sorig = single_succ_edge (switch_bb);
5832 sorig->flags = exits[1]->flags;
5833 snew = make_edge (switch_bb, nentry_bb, exits[0]->flags);
5835 /* Register the new edge from SWITCH_BB in loop exit lists. */
5836 rescan_loop_exit (snew, true, false);
5838 /* Add the PHI node arguments. */
5839 add_phi_args_after_copy (region_copy, n_region, snew);
5841 /* Get rid of now superfluous conditions and associated edges (and phi node
5843 e = redirect_edge_and_branch (exits[0], exits[1]->dest);
5844 PENDING_STMT (e) = NULL;
5845 e = redirect_edge_and_branch (nexits[1], nexits[0]->dest);
5846 PENDING_STMT (e) = NULL;
5848 /* Anything that is outside of the region, but was dominated by something
5849 inside needs to update dominance info. */
5850 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5851 VEC_free (basic_block, heap, doms);
5853 /* Update the SSA web. */
5854 update_ssa (TODO_update_ssa);
5856 if (free_region_copy)
5859 free_original_copy_tables ();
5863 /* Add all the blocks dominated by ENTRY to the array BBS_P. Stop
5864 adding blocks when the dominator traversal reaches EXIT. This
5865 function silently assumes that ENTRY strictly dominates EXIT. */
5868 gather_blocks_in_sese_region (basic_block entry, basic_block exit,
5869 VEC(basic_block,heap) **bbs_p)
5873 for (son = first_dom_son (CDI_DOMINATORS, entry);
5875 son = next_dom_son (CDI_DOMINATORS, son))
5877 VEC_safe_push (basic_block, heap, *bbs_p, son);
5879 gather_blocks_in_sese_region (son, exit, bbs_p);
5883 /* Replaces *TP with a duplicate (belonging to function TO_CONTEXT).
5884 The duplicates are recorded in VARS_MAP. */
5887 replace_by_duplicate_decl (tree *tp, struct pointer_map_t *vars_map,
5890 tree t = *tp, new_t;
5891 struct function *f = DECL_STRUCT_FUNCTION (to_context);
5894 if (DECL_CONTEXT (t) == to_context)
5897 loc = pointer_map_contains (vars_map, t);
5901 loc = pointer_map_insert (vars_map, t);
5905 new_t = copy_var_decl (t, DECL_NAME (t), TREE_TYPE (t));
5906 f->local_decls = tree_cons (NULL_TREE, new_t, f->local_decls);
5910 gcc_assert (TREE_CODE (t) == CONST_DECL);
5911 new_t = copy_node (t);
5913 DECL_CONTEXT (new_t) = to_context;
5918 new_t = (tree) *loc;
5924 /* Creates an ssa name in TO_CONTEXT equivalent to NAME.
5925 VARS_MAP maps old ssa names and var_decls to the new ones. */
5928 replace_ssa_name (tree name, struct pointer_map_t *vars_map,
5932 tree new_name, decl = SSA_NAME_VAR (name);
5934 gcc_assert (is_gimple_reg (name));
5936 loc = pointer_map_contains (vars_map, name);
5940 replace_by_duplicate_decl (&decl, vars_map, to_context);
5942 push_cfun (DECL_STRUCT_FUNCTION (to_context));
5943 if (gimple_in_ssa_p (cfun))
5944 add_referenced_var (decl);
5946 new_name = make_ssa_name (decl, SSA_NAME_DEF_STMT (name));
5947 if (SSA_NAME_IS_DEFAULT_DEF (name))
5948 set_default_def (decl, new_name);
5951 loc = pointer_map_insert (vars_map, name);
5955 new_name = (tree) *loc;
5966 struct pointer_map_t *vars_map;
5967 htab_t new_label_map;
5968 struct pointer_map_t *eh_map;
5972 /* Helper for move_block_to_fn. Set TREE_BLOCK in every expression
5973 contained in *TP if it has been ORIG_BLOCK previously and change the
5974 DECL_CONTEXT of every local variable referenced in *TP. */
5977 move_stmt_op (tree *tp, int *walk_subtrees, void *data)
5979 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
5980 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5984 /* We should never have TREE_BLOCK set on non-statements. */
5985 gcc_assert (!TREE_BLOCK (t));
5987 else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
5989 if (TREE_CODE (t) == SSA_NAME)
5990 *tp = replace_ssa_name (t, p->vars_map, p->to_context);
5991 else if (TREE_CODE (t) == LABEL_DECL)
5993 if (p->new_label_map)
5995 struct tree_map in, *out;
5997 out = (struct tree_map *)
5998 htab_find_with_hash (p->new_label_map, &in, DECL_UID (t));
6003 DECL_CONTEXT (t) = p->to_context;
6005 else if (p->remap_decls_p)
6007 /* Replace T with its duplicate. T should no longer appear in the
6008 parent function, so this looks wasteful; however, it may appear
6009 in referenced_vars, and more importantly, as virtual operands of
6010 statements, and in alias lists of other variables. It would be
6011 quite difficult to expunge it from all those places. ??? It might
6012 suffice to do this for addressable variables. */
6013 if ((TREE_CODE (t) == VAR_DECL
6014 && !is_global_var (t))
6015 || TREE_CODE (t) == CONST_DECL)
6016 replace_by_duplicate_decl (tp, p->vars_map, p->to_context);
6019 && gimple_in_ssa_p (cfun))
6021 push_cfun (DECL_STRUCT_FUNCTION (p->to_context));
6022 add_referenced_var (*tp);
6028 else if (TYPE_P (t))
6034 /* Helper for move_stmt_r. Given an EH region number for the source
6035 function, map that to the duplicate EH regio number in the dest. */
6038 move_stmt_eh_region_nr (int old_nr, struct move_stmt_d *p)
6040 eh_region old_r, new_r;
6043 old_r = get_eh_region_from_number (old_nr);
6044 slot = pointer_map_contains (p->eh_map, old_r);
6045 new_r = (eh_region) *slot;
6047 return new_r->index;
6050 /* Similar, but operate on INTEGER_CSTs. */
6053 move_stmt_eh_region_tree_nr (tree old_t_nr, struct move_stmt_d *p)
6057 old_nr = tree_low_cst (old_t_nr, 0);
6058 new_nr = move_stmt_eh_region_nr (old_nr, p);
6060 return build_int_cst (NULL, new_nr);
6063 /* Like move_stmt_op, but for gimple statements.
6065 Helper for move_block_to_fn. Set GIMPLE_BLOCK in every expression
6066 contained in the current statement in *GSI_P and change the
6067 DECL_CONTEXT of every local variable referenced in the current
6071 move_stmt_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
6072 struct walk_stmt_info *wi)
6074 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
6075 gimple stmt = gsi_stmt (*gsi_p);
6076 tree block = gimple_block (stmt);
6078 if (p->orig_block == NULL_TREE
6079 || block == p->orig_block
6080 || block == NULL_TREE)
6081 gimple_set_block (stmt, p->new_block);
6082 #ifdef ENABLE_CHECKING
6083 else if (block != p->new_block)
6085 while (block && block != p->orig_block)
6086 block = BLOCK_SUPERCONTEXT (block);
6091 switch (gimple_code (stmt))
6094 /* Remap the region numbers for __builtin_eh_{pointer,filter}. */
6096 tree r, fndecl = gimple_call_fndecl (stmt);
6097 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
6098 switch (DECL_FUNCTION_CODE (fndecl))
6100 case BUILT_IN_EH_COPY_VALUES:
6101 r = gimple_call_arg (stmt, 1);
6102 r = move_stmt_eh_region_tree_nr (r, p);
6103 gimple_call_set_arg (stmt, 1, r);
6106 case BUILT_IN_EH_POINTER:
6107 case BUILT_IN_EH_FILTER:
6108 r = gimple_call_arg (stmt, 0);
6109 r = move_stmt_eh_region_tree_nr (r, p);
6110 gimple_call_set_arg (stmt, 0, r);
6121 int r = gimple_resx_region (stmt);
6122 r = move_stmt_eh_region_nr (r, p);
6123 gimple_resx_set_region (stmt, r);
6127 case GIMPLE_EH_DISPATCH:
6129 int r = gimple_eh_dispatch_region (stmt);
6130 r = move_stmt_eh_region_nr (r, p);
6131 gimple_eh_dispatch_set_region (stmt, r);
6135 case GIMPLE_OMP_RETURN:
6136 case GIMPLE_OMP_CONTINUE:
6139 if (is_gimple_omp (stmt))
6141 /* Do not remap variables inside OMP directives. Variables
6142 referenced in clauses and directive header belong to the
6143 parent function and should not be moved into the child
6145 bool save_remap_decls_p = p->remap_decls_p;
6146 p->remap_decls_p = false;
6147 *handled_ops_p = true;
6149 walk_gimple_seq (gimple_omp_body (stmt), move_stmt_r,
6152 p->remap_decls_p = save_remap_decls_p;
6160 /* Marks virtual operands of all statements in basic blocks BBS for
6164 mark_virtual_ops_in_bb (basic_block bb)
6166 gimple_stmt_iterator gsi;
6168 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
6169 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
6171 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
6172 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
6175 /* Move basic block BB from function CFUN to function DEST_FN. The
6176 block is moved out of the original linked list and placed after
6177 block AFTER in the new list. Also, the block is removed from the
6178 original array of blocks and placed in DEST_FN's array of blocks.
6179 If UPDATE_EDGE_COUNT_P is true, the edge counts on both CFGs is
6180 updated to reflect the moved edges.
6182 The local variables are remapped to new instances, VARS_MAP is used
6183 to record the mapping. */
6186 move_block_to_fn (struct function *dest_cfun, basic_block bb,
6187 basic_block after, bool update_edge_count_p,
6188 struct move_stmt_d *d)
6190 struct control_flow_graph *cfg;
6193 gimple_stmt_iterator si;
6194 unsigned old_len, new_len;
6196 /* Remove BB from dominance structures. */
6197 delete_from_dominance_info (CDI_DOMINATORS, bb);
6199 remove_bb_from_loops (bb);
6201 /* Link BB to the new linked list. */
6202 move_block_after (bb, after);
6204 /* Update the edge count in the corresponding flowgraphs. */
6205 if (update_edge_count_p)
6206 FOR_EACH_EDGE (e, ei, bb->succs)
6208 cfun->cfg->x_n_edges--;
6209 dest_cfun->cfg->x_n_edges++;
6212 /* Remove BB from the original basic block array. */
6213 VEC_replace (basic_block, cfun->cfg->x_basic_block_info, bb->index, NULL);
6214 cfun->cfg->x_n_basic_blocks--;
6216 /* Grow DEST_CFUN's basic block array if needed. */
6217 cfg = dest_cfun->cfg;
6218 cfg->x_n_basic_blocks++;
6219 if (bb->index >= cfg->x_last_basic_block)
6220 cfg->x_last_basic_block = bb->index + 1;
6222 old_len = VEC_length (basic_block, cfg->x_basic_block_info);
6223 if ((unsigned) cfg->x_last_basic_block >= old_len)
6225 new_len = cfg->x_last_basic_block + (cfg->x_last_basic_block + 3) / 4;
6226 VEC_safe_grow_cleared (basic_block, gc, cfg->x_basic_block_info,
6230 VEC_replace (basic_block, cfg->x_basic_block_info,
6233 /* Remap the variables in phi nodes. */
6234 for (si = gsi_start_phis (bb); !gsi_end_p (si); )
6236 gimple phi = gsi_stmt (si);
6238 tree op = PHI_RESULT (phi);
6241 if (!is_gimple_reg (op))
6243 /* Remove the phi nodes for virtual operands (alias analysis will be
6244 run for the new function, anyway). */
6245 remove_phi_node (&si, true);
6249 SET_PHI_RESULT (phi,
6250 replace_ssa_name (op, d->vars_map, dest_cfun->decl));
6251 FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
6253 op = USE_FROM_PTR (use);
6254 if (TREE_CODE (op) == SSA_NAME)
6255 SET_USE (use, replace_ssa_name (op, d->vars_map, dest_cfun->decl));
6261 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
6263 gimple stmt = gsi_stmt (si);
6264 struct walk_stmt_info wi;
6266 memset (&wi, 0, sizeof (wi));
6268 walk_gimple_stmt (&si, move_stmt_r, move_stmt_op, &wi);
6270 if (gimple_code (stmt) == GIMPLE_LABEL)
6272 tree label = gimple_label_label (stmt);
6273 int uid = LABEL_DECL_UID (label);
6275 gcc_assert (uid > -1);
6277 old_len = VEC_length (basic_block, cfg->x_label_to_block_map);
6278 if (old_len <= (unsigned) uid)
6280 new_len = 3 * uid / 2 + 1;
6281 VEC_safe_grow_cleared (basic_block, gc,
6282 cfg->x_label_to_block_map, new_len);
6285 VEC_replace (basic_block, cfg->x_label_to_block_map, uid, bb);
6286 VEC_replace (basic_block, cfun->cfg->x_label_to_block_map, uid, NULL);
6288 gcc_assert (DECL_CONTEXT (label) == dest_cfun->decl);
6290 if (uid >= dest_cfun->cfg->last_label_uid)
6291 dest_cfun->cfg->last_label_uid = uid + 1;
6294 maybe_duplicate_eh_stmt_fn (dest_cfun, stmt, cfun, stmt, d->eh_map, 0);
6295 remove_stmt_from_eh_lp_fn (cfun, stmt);
6297 gimple_duplicate_stmt_histograms (dest_cfun, stmt, cfun, stmt);
6298 gimple_remove_stmt_histograms (cfun, stmt);
6300 /* We cannot leave any operands allocated from the operand caches of
6301 the current function. */
6302 free_stmt_operands (stmt);
6303 push_cfun (dest_cfun);
6308 FOR_EACH_EDGE (e, ei, bb->succs)
6311 tree block = e->goto_block;
6312 if (d->orig_block == NULL_TREE
6313 || block == d->orig_block)
6314 e->goto_block = d->new_block;
6315 #ifdef ENABLE_CHECKING
6316 else if (block != d->new_block)
6318 while (block && block != d->orig_block)
6319 block = BLOCK_SUPERCONTEXT (block);
6326 /* Examine the statements in BB (which is in SRC_CFUN); find and return
6327 the outermost EH region. Use REGION as the incoming base EH region. */
6330 find_outermost_region_in_block (struct function *src_cfun,
6331 basic_block bb, eh_region region)
6333 gimple_stmt_iterator si;
6335 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
6337 gimple stmt = gsi_stmt (si);
6338 eh_region stmt_region;
6341 lp_nr = lookup_stmt_eh_lp_fn (src_cfun, stmt);
6342 stmt_region = get_eh_region_from_lp_number_fn (src_cfun, lp_nr);
6346 region = stmt_region;
6347 else if (stmt_region != region)
6349 region = eh_region_outermost (src_cfun, stmt_region, region);
6350 gcc_assert (region != NULL);
6359 new_label_mapper (tree decl, void *data)
6361 htab_t hash = (htab_t) data;
6365 gcc_assert (TREE_CODE (decl) == LABEL_DECL);
6367 m = XNEW (struct tree_map);
6368 m->hash = DECL_UID (decl);
6369 m->base.from = decl;
6370 m->to = create_artificial_label (UNKNOWN_LOCATION);
6371 LABEL_DECL_UID (m->to) = LABEL_DECL_UID (decl);
6372 if (LABEL_DECL_UID (m->to) >= cfun->cfg->last_label_uid)
6373 cfun->cfg->last_label_uid = LABEL_DECL_UID (m->to) + 1;
6375 slot = htab_find_slot_with_hash (hash, m, m->hash, INSERT);
6376 gcc_assert (*slot == NULL);
6383 /* Change DECL_CONTEXT of all BLOCK_VARS in block, including
6387 replace_block_vars_by_duplicates (tree block, struct pointer_map_t *vars_map,
6392 for (tp = &BLOCK_VARS (block); *tp; tp = &TREE_CHAIN (*tp))
6395 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != CONST_DECL)
6397 replace_by_duplicate_decl (&t, vars_map, to_context);
6400 if (TREE_CODE (*tp) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (*tp))
6402 SET_DECL_VALUE_EXPR (t, DECL_VALUE_EXPR (*tp));
6403 DECL_HAS_VALUE_EXPR_P (t) = 1;
6405 TREE_CHAIN (t) = TREE_CHAIN (*tp);
6410 for (block = BLOCK_SUBBLOCKS (block); block; block = BLOCK_CHAIN (block))
6411 replace_block_vars_by_duplicates (block, vars_map, to_context);
6414 /* Move a single-entry, single-exit region delimited by ENTRY_BB and
6415 EXIT_BB to function DEST_CFUN. The whole region is replaced by a
6416 single basic block in the original CFG and the new basic block is
6417 returned. DEST_CFUN must not have a CFG yet.
6419 Note that the region need not be a pure SESE region. Blocks inside
6420 the region may contain calls to abort/exit. The only restriction
6421 is that ENTRY_BB should be the only entry point and it must
6424 Change TREE_BLOCK of all statements in ORIG_BLOCK to the new
6425 functions outermost BLOCK, move all subblocks of ORIG_BLOCK
6426 to the new function.
6428 All local variables referenced in the region are assumed to be in
6429 the corresponding BLOCK_VARS and unexpanded variable lists
6430 associated with DEST_CFUN. */
6433 move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb,
6434 basic_block exit_bb, tree orig_block)
6436 VEC(basic_block,heap) *bbs, *dom_bbs;
6437 basic_block dom_entry = get_immediate_dominator (CDI_DOMINATORS, entry_bb);
6438 basic_block after, bb, *entry_pred, *exit_succ, abb;
6439 struct function *saved_cfun = cfun;
6440 int *entry_flag, *exit_flag;
6441 unsigned *entry_prob, *exit_prob;
6442 unsigned i, num_entry_edges, num_exit_edges;
6445 htab_t new_label_map;
6446 struct pointer_map_t *vars_map, *eh_map;
6447 struct loop *loop = entry_bb->loop_father;
6448 struct move_stmt_d d;
6450 /* If ENTRY does not strictly dominate EXIT, this cannot be an SESE
6452 gcc_assert (entry_bb != exit_bb
6454 || dominated_by_p (CDI_DOMINATORS, exit_bb, entry_bb)));
6456 /* Collect all the blocks in the region. Manually add ENTRY_BB
6457 because it won't be added by dfs_enumerate_from. */
6459 VEC_safe_push (basic_block, heap, bbs, entry_bb);
6460 gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs);
6462 /* The blocks that used to be dominated by something in BBS will now be
6463 dominated by the new block. */
6464 dom_bbs = get_dominated_by_region (CDI_DOMINATORS,
6465 VEC_address (basic_block, bbs),
6466 VEC_length (basic_block, bbs));
6468 /* Detach ENTRY_BB and EXIT_BB from CFUN->CFG. We need to remember
6469 the predecessor edges to ENTRY_BB and the successor edges to
6470 EXIT_BB so that we can re-attach them to the new basic block that
6471 will replace the region. */
6472 num_entry_edges = EDGE_COUNT (entry_bb->preds);
6473 entry_pred = (basic_block *) xcalloc (num_entry_edges, sizeof (basic_block));
6474 entry_flag = (int *) xcalloc (num_entry_edges, sizeof (int));
6475 entry_prob = XNEWVEC (unsigned, num_entry_edges);
6477 for (ei = ei_start (entry_bb->preds); (e = ei_safe_edge (ei)) != NULL;)
6479 entry_prob[i] = e->probability;
6480 entry_flag[i] = e->flags;
6481 entry_pred[i++] = e->src;
6487 num_exit_edges = EDGE_COUNT (exit_bb->succs);
6488 exit_succ = (basic_block *) xcalloc (num_exit_edges,
6489 sizeof (basic_block));
6490 exit_flag = (int *) xcalloc (num_exit_edges, sizeof (int));
6491 exit_prob = XNEWVEC (unsigned, num_exit_edges);
6493 for (ei = ei_start (exit_bb->succs); (e = ei_safe_edge (ei)) != NULL;)
6495 exit_prob[i] = e->probability;
6496 exit_flag[i] = e->flags;
6497 exit_succ[i++] = e->dest;
6509 /* Switch context to the child function to initialize DEST_FN's CFG. */
6510 gcc_assert (dest_cfun->cfg == NULL);
6511 push_cfun (dest_cfun);
6513 init_empty_tree_cfg ();
6515 /* Initialize EH information for the new function. */
6517 new_label_map = NULL;
6520 eh_region region = NULL;
6522 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6523 region = find_outermost_region_in_block (saved_cfun, bb, region);
6525 init_eh_for_function ();
6528 new_label_map = htab_create (17, tree_map_hash, tree_map_eq, free);
6529 eh_map = duplicate_eh_regions (saved_cfun, region, 0,
6530 new_label_mapper, new_label_map);
6536 /* Move blocks from BBS into DEST_CFUN. */
6537 gcc_assert (VEC_length (basic_block, bbs) >= 2);
6538 after = dest_cfun->cfg->x_entry_block_ptr;
6539 vars_map = pointer_map_create ();
6541 memset (&d, 0, sizeof (d));
6542 d.orig_block = orig_block;
6543 d.new_block = DECL_INITIAL (dest_cfun->decl);
6544 d.from_context = cfun->decl;
6545 d.to_context = dest_cfun->decl;
6546 d.vars_map = vars_map;
6547 d.new_label_map = new_label_map;
6549 d.remap_decls_p = true;
6551 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6553 /* No need to update edge counts on the last block. It has
6554 already been updated earlier when we detached the region from
6555 the original CFG. */
6556 move_block_to_fn (dest_cfun, bb, after, bb != exit_bb, &d);
6560 /* Rewire BLOCK_SUBBLOCKS of orig_block. */
6564 gcc_assert (BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6566 BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6567 = BLOCK_SUBBLOCKS (orig_block);
6568 for (block = BLOCK_SUBBLOCKS (orig_block);
6569 block; block = BLOCK_CHAIN (block))
6570 BLOCK_SUPERCONTEXT (block) = DECL_INITIAL (dest_cfun->decl);
6571 BLOCK_SUBBLOCKS (orig_block) = NULL_TREE;
6574 replace_block_vars_by_duplicates (DECL_INITIAL (dest_cfun->decl),
6575 vars_map, dest_cfun->decl);
6578 htab_delete (new_label_map);
6580 pointer_map_destroy (eh_map);
6581 pointer_map_destroy (vars_map);
6583 /* Rewire the entry and exit blocks. The successor to the entry
6584 block turns into the successor of DEST_FN's ENTRY_BLOCK_PTR in
6585 the child function. Similarly, the predecessor of DEST_FN's
6586 EXIT_BLOCK_PTR turns into the predecessor of EXIT_BLOCK_PTR. We
6587 need to switch CFUN between DEST_CFUN and SAVED_CFUN so that the
6588 various CFG manipulation function get to the right CFG.
6590 FIXME, this is silly. The CFG ought to become a parameter to
6592 push_cfun (dest_cfun);
6593 make_edge (ENTRY_BLOCK_PTR, entry_bb, EDGE_FALLTHRU);
6595 make_edge (exit_bb, EXIT_BLOCK_PTR, 0);
6598 /* Back in the original function, the SESE region has disappeared,
6599 create a new basic block in its place. */
6600 bb = create_empty_bb (entry_pred[0]);
6602 add_bb_to_loop (bb, loop);
6603 for (i = 0; i < num_entry_edges; i++)
6605 e = make_edge (entry_pred[i], bb, entry_flag[i]);
6606 e->probability = entry_prob[i];
6609 for (i = 0; i < num_exit_edges; i++)
6611 e = make_edge (bb, exit_succ[i], exit_flag[i]);
6612 e->probability = exit_prob[i];
6615 set_immediate_dominator (CDI_DOMINATORS, bb, dom_entry);
6616 for (i = 0; VEC_iterate (basic_block, dom_bbs, i, abb); i++)
6617 set_immediate_dominator (CDI_DOMINATORS, abb, bb);
6618 VEC_free (basic_block, heap, dom_bbs);
6629 VEC_free (basic_block, heap, bbs);
6635 /* Dump FUNCTION_DECL FN to file FILE using FLAGS (see TDF_* in tree-pass.h)
6639 dump_function_to_file (tree fn, FILE *file, int flags)
6641 tree arg, vars, var;
6642 struct function *dsf;
6643 bool ignore_topmost_bind = false, any_var = false;
6647 fprintf (file, "%s (", lang_hooks.decl_printable_name (fn, 2));
6649 arg = DECL_ARGUMENTS (fn);
6652 print_generic_expr (file, TREE_TYPE (arg), dump_flags);
6653 fprintf (file, " ");
6654 print_generic_expr (file, arg, dump_flags);
6655 if (flags & TDF_VERBOSE)
6656 print_node (file, "", arg, 4);
6657 if (TREE_CHAIN (arg))
6658 fprintf (file, ", ");
6659 arg = TREE_CHAIN (arg);
6661 fprintf (file, ")\n");
6663 if (flags & TDF_VERBOSE)
6664 print_node (file, "", fn, 2);
6666 dsf = DECL_STRUCT_FUNCTION (fn);
6667 if (dsf && (flags & TDF_EH))
6668 dump_eh_tree (file, dsf);
6670 if (flags & TDF_RAW && !gimple_has_body_p (fn))
6672 dump_node (fn, TDF_SLIM | flags, file);
6676 /* Switch CFUN to point to FN. */
6677 push_cfun (DECL_STRUCT_FUNCTION (fn));
6679 /* When GIMPLE is lowered, the variables are no longer available in
6680 BIND_EXPRs, so display them separately. */
6681 if (cfun && cfun->decl == fn && cfun->local_decls)
6683 ignore_topmost_bind = true;
6685 fprintf (file, "{\n");
6686 for (vars = cfun->local_decls; vars; vars = TREE_CHAIN (vars))
6688 var = TREE_VALUE (vars);
6690 print_generic_decl (file, var, flags);
6691 if (flags & TDF_VERBOSE)
6692 print_node (file, "", var, 4);
6693 fprintf (file, "\n");
6699 if (cfun && cfun->decl == fn && cfun->cfg && basic_block_info)
6701 /* If the CFG has been built, emit a CFG-based dump. */
6702 check_bb_profile (ENTRY_BLOCK_PTR, file);
6703 if (!ignore_topmost_bind)
6704 fprintf (file, "{\n");
6706 if (any_var && n_basic_blocks)
6707 fprintf (file, "\n");
6710 gimple_dump_bb (bb, file, 2, flags);
6712 fprintf (file, "}\n");
6713 check_bb_profile (EXIT_BLOCK_PTR, file);
6715 else if (DECL_SAVED_TREE (fn) == NULL)
6717 /* The function is now in GIMPLE form but the CFG has not been
6718 built yet. Emit the single sequence of GIMPLE statements
6719 that make up its body. */
6720 gimple_seq body = gimple_body (fn);
6722 if (gimple_seq_first_stmt (body)
6723 && gimple_seq_first_stmt (body) == gimple_seq_last_stmt (body)
6724 && gimple_code (gimple_seq_first_stmt (body)) == GIMPLE_BIND)
6725 print_gimple_seq (file, body, 0, flags);
6728 if (!ignore_topmost_bind)
6729 fprintf (file, "{\n");
6732 fprintf (file, "\n");
6734 print_gimple_seq (file, body, 2, flags);
6735 fprintf (file, "}\n");
6742 /* Make a tree based dump. */
6743 chain = DECL_SAVED_TREE (fn);
6745 if (chain && TREE_CODE (chain) == BIND_EXPR)
6747 if (ignore_topmost_bind)
6749 chain = BIND_EXPR_BODY (chain);
6757 if (!ignore_topmost_bind)
6758 fprintf (file, "{\n");
6763 fprintf (file, "\n");
6765 print_generic_stmt_indented (file, chain, flags, indent);
6766 if (ignore_topmost_bind)
6767 fprintf (file, "}\n");
6770 fprintf (file, "\n\n");
6777 /* Dump FUNCTION_DECL FN to stderr using FLAGS (see TDF_* in tree.h) */
6780 debug_function (tree fn, int flags)
6782 dump_function_to_file (fn, stderr, flags);
6786 /* Print on FILE the indexes for the predecessors of basic_block BB. */
6789 print_pred_bbs (FILE *file, basic_block bb)
6794 FOR_EACH_EDGE (e, ei, bb->preds)
6795 fprintf (file, "bb_%d ", e->src->index);
6799 /* Print on FILE the indexes for the successors of basic_block BB. */
6802 print_succ_bbs (FILE *file, basic_block bb)
6807 FOR_EACH_EDGE (e, ei, bb->succs)
6808 fprintf (file, "bb_%d ", e->dest->index);
6811 /* Print to FILE the basic block BB following the VERBOSITY level. */
6814 print_loops_bb (FILE *file, basic_block bb, int indent, int verbosity)
6816 char *s_indent = (char *) alloca ((size_t) indent + 1);
6817 memset ((void *) s_indent, ' ', (size_t) indent);
6818 s_indent[indent] = '\0';
6820 /* Print basic_block's header. */
6823 fprintf (file, "%s bb_%d (preds = {", s_indent, bb->index);
6824 print_pred_bbs (file, bb);
6825 fprintf (file, "}, succs = {");
6826 print_succ_bbs (file, bb);
6827 fprintf (file, "})\n");
6830 /* Print basic_block's body. */
6833 fprintf (file, "%s {\n", s_indent);
6834 gimple_dump_bb (bb, file, indent + 4, TDF_VOPS|TDF_MEMSYMS);
6835 fprintf (file, "%s }\n", s_indent);
6839 static void print_loop_and_siblings (FILE *, struct loop *, int, int);
6841 /* Pretty print LOOP on FILE, indented INDENT spaces. Following
6842 VERBOSITY level this outputs the contents of the loop, or just its
6846 print_loop (FILE *file, struct loop *loop, int indent, int verbosity)
6854 s_indent = (char *) alloca ((size_t) indent + 1);
6855 memset ((void *) s_indent, ' ', (size_t) indent);
6856 s_indent[indent] = '\0';
6858 /* Print loop's header. */
6859 fprintf (file, "%sloop_%d (header = %d, latch = %d", s_indent,
6860 loop->num, loop->header->index, loop->latch->index);
6861 fprintf (file, ", niter = ");
6862 print_generic_expr (file, loop->nb_iterations, 0);
6864 if (loop->any_upper_bound)
6866 fprintf (file, ", upper_bound = ");
6867 dump_double_int (file, loop->nb_iterations_upper_bound, true);
6870 if (loop->any_estimate)
6872 fprintf (file, ", estimate = ");
6873 dump_double_int (file, loop->nb_iterations_estimate, true);
6875 fprintf (file, ")\n");
6877 /* Print loop's body. */
6880 fprintf (file, "%s{\n", s_indent);
6882 if (bb->loop_father == loop)
6883 print_loops_bb (file, bb, indent, verbosity);
6885 print_loop_and_siblings (file, loop->inner, indent + 2, verbosity);
6886 fprintf (file, "%s}\n", s_indent);
6890 /* Print the LOOP and its sibling loops on FILE, indented INDENT
6891 spaces. Following VERBOSITY level this outputs the contents of the
6892 loop, or just its structure. */
6895 print_loop_and_siblings (FILE *file, struct loop *loop, int indent, int verbosity)
6900 print_loop (file, loop, indent, verbosity);
6901 print_loop_and_siblings (file, loop->next, indent, verbosity);
6904 /* Follow a CFG edge from the entry point of the program, and on entry
6905 of a loop, pretty print the loop structure on FILE. */
6908 print_loops (FILE *file, int verbosity)
6912 bb = ENTRY_BLOCK_PTR;
6913 if (bb && bb->loop_father)
6914 print_loop_and_siblings (file, bb->loop_father, 0, verbosity);
6918 /* Debugging loops structure at tree level, at some VERBOSITY level. */
6921 debug_loops (int verbosity)
6923 print_loops (stderr, verbosity);
6926 /* Print on stderr the code of LOOP, at some VERBOSITY level. */
6929 debug_loop (struct loop *loop, int verbosity)
6931 print_loop (stderr, loop, 0, verbosity);
6934 /* Print on stderr the code of loop number NUM, at some VERBOSITY
6938 debug_loop_num (unsigned num, int verbosity)
6940 debug_loop (get_loop (num), verbosity);
6943 /* Return true if BB ends with a call, possibly followed by some
6944 instructions that must stay with the call. Return false,
6948 gimple_block_ends_with_call_p (basic_block bb)
6950 gimple_stmt_iterator gsi = gsi_last_nondebug_bb (bb);
6951 return is_gimple_call (gsi_stmt (gsi));
6955 /* Return true if BB ends with a conditional branch. Return false,
6959 gimple_block_ends_with_condjump_p (const_basic_block bb)
6961 gimple stmt = last_stmt (CONST_CAST_BB (bb));
6962 return (stmt && gimple_code (stmt) == GIMPLE_COND);
6966 /* Return true if we need to add fake edge to exit at statement T.
6967 Helper function for gimple_flow_call_edges_add. */
6970 need_fake_edge_p (gimple t)
6972 tree fndecl = NULL_TREE;
6975 /* NORETURN and LONGJMP calls already have an edge to exit.
6976 CONST and PURE calls do not need one.
6977 We don't currently check for CONST and PURE here, although
6978 it would be a good idea, because those attributes are
6979 figured out from the RTL in mark_constant_function, and
6980 the counter incrementation code from -fprofile-arcs
6981 leads to different results from -fbranch-probabilities. */
6982 if (is_gimple_call (t))
6984 fndecl = gimple_call_fndecl (t);
6985 call_flags = gimple_call_flags (t);
6988 if (is_gimple_call (t)
6990 && DECL_BUILT_IN (fndecl)
6991 && (call_flags & ECF_NOTHROW)
6992 && !(call_flags & ECF_RETURNS_TWICE)
6993 /* fork() doesn't really return twice, but the effect of
6994 wrapping it in __gcov_fork() which calls __gcov_flush()
6995 and clears the counters before forking has the same
6996 effect as returning twice. Force a fake edge. */
6997 && !(DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6998 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_FORK))
7001 if (is_gimple_call (t)
7002 && !(call_flags & ECF_NORETURN))
7005 if (gimple_code (t) == GIMPLE_ASM
7006 && (gimple_asm_volatile_p (t) || gimple_asm_input_p (t)))
7013 /* Add fake edges to the function exit for any non constant and non
7014 noreturn calls, volatile inline assembly in the bitmap of blocks
7015 specified by BLOCKS or to the whole CFG if BLOCKS is zero. Return
7016 the number of blocks that were split.
7018 The goal is to expose cases in which entering a basic block does
7019 not imply that all subsequent instructions must be executed. */
7022 gimple_flow_call_edges_add (sbitmap blocks)
7025 int blocks_split = 0;
7026 int last_bb = last_basic_block;
7027 bool check_last_block = false;
7029 if (n_basic_blocks == NUM_FIXED_BLOCKS)
7033 check_last_block = true;
7035 check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index);
7037 /* In the last basic block, before epilogue generation, there will be
7038 a fallthru edge to EXIT. Special care is required if the last insn
7039 of the last basic block is a call because make_edge folds duplicate
7040 edges, which would result in the fallthru edge also being marked
7041 fake, which would result in the fallthru edge being removed by
7042 remove_fake_edges, which would result in an invalid CFG.
7044 Moreover, we can't elide the outgoing fake edge, since the block
7045 profiler needs to take this into account in order to solve the minimal
7046 spanning tree in the case that the call doesn't return.
7048 Handle this by adding a dummy instruction in a new last basic block. */
7049 if (check_last_block)
7051 basic_block bb = EXIT_BLOCK_PTR->prev_bb;
7052 gimple_stmt_iterator gsi = gsi_last_bb (bb);
7055 if (!gsi_end_p (gsi))
7058 if (t && need_fake_edge_p (t))
7062 e = find_edge (bb, EXIT_BLOCK_PTR);
7065 gsi_insert_on_edge (e, gimple_build_nop ());
7066 gsi_commit_edge_inserts ();
7071 /* Now add fake edges to the function exit for any non constant
7072 calls since there is no way that we can determine if they will
7074 for (i = 0; i < last_bb; i++)
7076 basic_block bb = BASIC_BLOCK (i);
7077 gimple_stmt_iterator gsi;
7078 gimple stmt, last_stmt;
7083 if (blocks && !TEST_BIT (blocks, i))
7086 gsi = gsi_last_bb (bb);
7087 if (!gsi_end_p (gsi))
7089 last_stmt = gsi_stmt (gsi);
7092 stmt = gsi_stmt (gsi);
7093 if (need_fake_edge_p (stmt))
7097 /* The handling above of the final block before the
7098 epilogue should be enough to verify that there is
7099 no edge to the exit block in CFG already.
7100 Calling make_edge in such case would cause us to
7101 mark that edge as fake and remove it later. */
7102 #ifdef ENABLE_CHECKING
7103 if (stmt == last_stmt)
7105 e = find_edge (bb, EXIT_BLOCK_PTR);
7106 gcc_assert (e == NULL);
7110 /* Note that the following may create a new basic block
7111 and renumber the existing basic blocks. */
7112 if (stmt != last_stmt)
7114 e = split_block (bb, stmt);
7118 make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE);
7122 while (!gsi_end_p (gsi));
7127 verify_flow_info ();
7129 return blocks_split;
7132 /* Purge dead abnormal call edges from basic block BB. */
7135 gimple_purge_dead_abnormal_call_edges (basic_block bb)
7137 bool changed = gimple_purge_dead_eh_edges (bb);
7139 if (cfun->has_nonlocal_label)
7141 gimple stmt = last_stmt (bb);
7145 if (!(stmt && stmt_can_make_abnormal_goto (stmt)))
7146 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
7148 if (e->flags & EDGE_ABNORMAL)
7157 /* See gimple_purge_dead_eh_edges below. */
7159 free_dominance_info (CDI_DOMINATORS);
7165 /* Removes edge E and all the blocks dominated by it, and updates dominance
7166 information. The IL in E->src needs to be updated separately.
7167 If dominance info is not available, only the edge E is removed.*/
7170 remove_edge_and_dominated_blocks (edge e)
7172 VEC (basic_block, heap) *bbs_to_remove = NULL;
7173 VEC (basic_block, heap) *bbs_to_fix_dom = NULL;
7177 bool none_removed = false;
7179 basic_block bb, dbb;
7182 if (!dom_info_available_p (CDI_DOMINATORS))
7188 /* No updating is needed for edges to exit. */
7189 if (e->dest == EXIT_BLOCK_PTR)
7191 if (cfgcleanup_altered_bbs)
7192 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
7197 /* First, we find the basic blocks to remove. If E->dest has a predecessor
7198 that is not dominated by E->dest, then this set is empty. Otherwise,
7199 all the basic blocks dominated by E->dest are removed.
7201 Also, to DF_IDOM we store the immediate dominators of the blocks in
7202 the dominance frontier of E (i.e., of the successors of the
7203 removed blocks, if there are any, and of E->dest otherwise). */
7204 FOR_EACH_EDGE (f, ei, e->dest->preds)
7209 if (!dominated_by_p (CDI_DOMINATORS, f->src, e->dest))
7211 none_removed = true;
7216 df = BITMAP_ALLOC (NULL);
7217 df_idom = BITMAP_ALLOC (NULL);
7220 bitmap_set_bit (df_idom,
7221 get_immediate_dominator (CDI_DOMINATORS, e->dest)->index);
7224 bbs_to_remove = get_all_dominated_blocks (CDI_DOMINATORS, e->dest);
7225 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
7227 FOR_EACH_EDGE (f, ei, bb->succs)
7229 if (f->dest != EXIT_BLOCK_PTR)
7230 bitmap_set_bit (df, f->dest->index);
7233 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
7234 bitmap_clear_bit (df, bb->index);
7236 EXECUTE_IF_SET_IN_BITMAP (df, 0, i, bi)
7238 bb = BASIC_BLOCK (i);
7239 bitmap_set_bit (df_idom,
7240 get_immediate_dominator (CDI_DOMINATORS, bb)->index);
7244 if (cfgcleanup_altered_bbs)
7246 /* Record the set of the altered basic blocks. */
7247 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
7248 bitmap_ior_into (cfgcleanup_altered_bbs, df);
7251 /* Remove E and the cancelled blocks. */
7256 /* Walk backwards so as to get a chance to substitute all
7257 released DEFs into debug stmts. See
7258 eliminate_unnecessary_stmts() in tree-ssa-dce.c for more
7260 for (i = VEC_length (basic_block, bbs_to_remove); i-- > 0; )
7261 delete_basic_block (VEC_index (basic_block, bbs_to_remove, i));
7264 /* Update the dominance information. The immediate dominator may change only
7265 for blocks whose immediate dominator belongs to DF_IDOM:
7267 Suppose that idom(X) = Y before removal of E and idom(X) != Y after the
7268 removal. Let Z the arbitrary block such that idom(Z) = Y and
7269 Z dominates X after the removal. Before removal, there exists a path P
7270 from Y to X that avoids Z. Let F be the last edge on P that is
7271 removed, and let W = F->dest. Before removal, idom(W) = Y (since Y
7272 dominates W, and because of P, Z does not dominate W), and W belongs to
7273 the dominance frontier of E. Therefore, Y belongs to DF_IDOM. */
7274 EXECUTE_IF_SET_IN_BITMAP (df_idom, 0, i, bi)
7276 bb = BASIC_BLOCK (i);
7277 for (dbb = first_dom_son (CDI_DOMINATORS, bb);
7279 dbb = next_dom_son (CDI_DOMINATORS, dbb))
7280 VEC_safe_push (basic_block, heap, bbs_to_fix_dom, dbb);
7283 iterate_fix_dominators (CDI_DOMINATORS, bbs_to_fix_dom, true);
7286 BITMAP_FREE (df_idom);
7287 VEC_free (basic_block, heap, bbs_to_remove);
7288 VEC_free (basic_block, heap, bbs_to_fix_dom);
7291 /* Purge dead EH edges from basic block BB. */
7294 gimple_purge_dead_eh_edges (basic_block bb)
7296 bool changed = false;
7299 gimple stmt = last_stmt (bb);
7301 if (stmt && stmt_can_throw_internal (stmt))
7304 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
7306 if (e->flags & EDGE_EH)
7308 remove_edge_and_dominated_blocks (e);
7319 gimple_purge_all_dead_eh_edges (const_bitmap blocks)
7321 bool changed = false;
7325 EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
7327 basic_block bb = BASIC_BLOCK (i);
7329 /* Earlier gimple_purge_dead_eh_edges could have removed
7330 this basic block already. */
7331 gcc_assert (bb || changed);
7333 changed |= gimple_purge_dead_eh_edges (bb);
7339 /* This function is called whenever a new edge is created or
7343 gimple_execute_on_growing_pred (edge e)
7345 basic_block bb = e->dest;
7348 reserve_phi_args_for_new_edge (bb);
7351 /* This function is called immediately before edge E is removed from
7352 the edge vector E->dest->preds. */
7355 gimple_execute_on_shrinking_pred (edge e)
7357 if (phi_nodes (e->dest))
7358 remove_phi_args (e);
7361 /*---------------------------------------------------------------------------
7362 Helper functions for Loop versioning
7363 ---------------------------------------------------------------------------*/
7365 /* Adjust phi nodes for 'first' basic block. 'second' basic block is a copy
7366 of 'first'. Both of them are dominated by 'new_head' basic block. When
7367 'new_head' was created by 'second's incoming edge it received phi arguments
7368 on the edge by split_edge(). Later, additional edge 'e' was created to
7369 connect 'new_head' and 'first'. Now this routine adds phi args on this
7370 additional edge 'e' that new_head to second edge received as part of edge
7374 gimple_lv_adjust_loop_header_phi (basic_block first, basic_block second,
7375 basic_block new_head, edge e)
7378 gimple_stmt_iterator psi1, psi2;
7380 edge e2 = find_edge (new_head, second);
7382 /* Because NEW_HEAD has been created by splitting SECOND's incoming
7383 edge, we should always have an edge from NEW_HEAD to SECOND. */
7384 gcc_assert (e2 != NULL);
7386 /* Browse all 'second' basic block phi nodes and add phi args to
7387 edge 'e' for 'first' head. PHI args are always in correct order. */
7389 for (psi2 = gsi_start_phis (second),
7390 psi1 = gsi_start_phis (first);
7391 !gsi_end_p (psi2) && !gsi_end_p (psi1);
7392 gsi_next (&psi2), gsi_next (&psi1))
7394 phi1 = gsi_stmt (psi1);
7395 phi2 = gsi_stmt (psi2);
7396 def = PHI_ARG_DEF (phi2, e2->dest_idx);
7397 add_phi_arg (phi1, def, e, gimple_phi_arg_location_from_edge (phi2, e2));
7402 /* Adds a if else statement to COND_BB with condition COND_EXPR.
7403 SECOND_HEAD is the destination of the THEN and FIRST_HEAD is
7404 the destination of the ELSE part. */
7407 gimple_lv_add_condition_to_bb (basic_block first_head ATTRIBUTE_UNUSED,
7408 basic_block second_head ATTRIBUTE_UNUSED,
7409 basic_block cond_bb, void *cond_e)
7411 gimple_stmt_iterator gsi;
7412 gimple new_cond_expr;
7413 tree cond_expr = (tree) cond_e;
7416 /* Build new conditional expr */
7417 new_cond_expr = gimple_build_cond_from_tree (cond_expr,
7418 NULL_TREE, NULL_TREE);
7420 /* Add new cond in cond_bb. */
7421 gsi = gsi_last_bb (cond_bb);
7422 gsi_insert_after (&gsi, new_cond_expr, GSI_NEW_STMT);
7424 /* Adjust edges appropriately to connect new head with first head
7425 as well as second head. */
7426 e0 = single_succ_edge (cond_bb);
7427 e0->flags &= ~EDGE_FALLTHRU;
7428 e0->flags |= EDGE_FALSE_VALUE;
7431 struct cfg_hooks gimple_cfg_hooks = {
7433 gimple_verify_flow_info,
7434 gimple_dump_bb, /* dump_bb */
7435 create_bb, /* create_basic_block */
7436 gimple_redirect_edge_and_branch, /* redirect_edge_and_branch */
7437 gimple_redirect_edge_and_branch_force, /* redirect_edge_and_branch_force */
7438 gimple_can_remove_branch_p, /* can_remove_branch_p */
7439 remove_bb, /* delete_basic_block */
7440 gimple_split_block, /* split_block */
7441 gimple_move_block_after, /* move_block_after */
7442 gimple_can_merge_blocks_p, /* can_merge_blocks_p */
7443 gimple_merge_blocks, /* merge_blocks */
7444 gimple_predict_edge, /* predict_edge */
7445 gimple_predicted_by_p, /* predicted_by_p */
7446 gimple_can_duplicate_bb_p, /* can_duplicate_block_p */
7447 gimple_duplicate_bb, /* duplicate_block */
7448 gimple_split_edge, /* split_edge */
7449 gimple_make_forwarder_block, /* make_forward_block */
7450 NULL, /* tidy_fallthru_edge */
7451 gimple_block_ends_with_call_p,/* block_ends_with_call_p */
7452 gimple_block_ends_with_condjump_p, /* block_ends_with_condjump_p */
7453 gimple_flow_call_edges_add, /* flow_call_edges_add */
7454 gimple_execute_on_growing_pred, /* execute_on_growing_pred */
7455 gimple_execute_on_shrinking_pred, /* execute_on_shrinking_pred */
7456 gimple_duplicate_loop_to_header_edge, /* duplicate loop for trees */
7457 gimple_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
7458 gimple_lv_adjust_loop_header_phi, /* lv_adjust_loop_header_phi*/
7459 extract_true_false_edges_from_block, /* extract_cond_bb_edges */
7460 flush_pending_stmts /* flush_pending_stmts */
7464 /* Split all critical edges. */
7467 split_critical_edges (void)
7473 /* split_edge can redirect edges out of SWITCH_EXPRs, which can get
7474 expensive. So we want to enable recording of edge to CASE_LABEL_EXPR
7475 mappings around the calls to split_edge. */
7476 start_recording_case_labels ();
7479 FOR_EACH_EDGE (e, ei, bb->succs)
7481 if (EDGE_CRITICAL_P (e) && !(e->flags & EDGE_ABNORMAL))
7483 /* PRE inserts statements to edges and expects that
7484 since split_critical_edges was done beforehand, committing edge
7485 insertions will not split more edges. In addition to critical
7486 edges we must split edges that have multiple successors and
7487 end by control flow statements, such as RESX.
7488 Go ahead and split them too. This matches the logic in
7489 gimple_find_edge_insert_loc. */
7490 else if ((!single_pred_p (e->dest)
7491 || !gimple_seq_empty_p (phi_nodes (e->dest))
7492 || e->dest == EXIT_BLOCK_PTR)
7493 && e->src != ENTRY_BLOCK_PTR
7494 && !(e->flags & EDGE_ABNORMAL))
7496 gimple_stmt_iterator gsi;
7498 gsi = gsi_last_bb (e->src);
7499 if (!gsi_end_p (gsi)
7500 && stmt_ends_bb_p (gsi_stmt (gsi))
7501 && gimple_code (gsi_stmt (gsi)) != GIMPLE_RETURN)
7506 end_recording_case_labels ();
7510 struct gimple_opt_pass pass_split_crit_edges =
7514 "crited", /* name */
7516 split_critical_edges, /* execute */
7519 0, /* static_pass_number */
7520 TV_TREE_SPLIT_EDGES, /* tv_id */
7521 PROP_cfg, /* properties required */
7522 PROP_no_crit_edges, /* properties_provided */
7523 0, /* properties_destroyed */
7524 0, /* todo_flags_start */
7525 TODO_dump_func | TODO_verify_flow /* todo_flags_finish */
7530 /* Build a ternary operation and gimplify it. Emit code before GSI.
7531 Return the gimple_val holding the result. */
7534 gimplify_build3 (gimple_stmt_iterator *gsi, enum tree_code code,
7535 tree type, tree a, tree b, tree c)
7538 location_t loc = gimple_location (gsi_stmt (*gsi));
7540 ret = fold_build3_loc (loc, code, type, a, b, c);
7543 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7547 /* Build a binary operation and gimplify it. Emit code before GSI.
7548 Return the gimple_val holding the result. */
7551 gimplify_build2 (gimple_stmt_iterator *gsi, enum tree_code code,
7552 tree type, tree a, tree b)
7556 ret = fold_build2_loc (gimple_location (gsi_stmt (*gsi)), code, type, a, b);
7559 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7563 /* Build a unary operation and gimplify it. Emit code before GSI.
7564 Return the gimple_val holding the result. */
7567 gimplify_build1 (gimple_stmt_iterator *gsi, enum tree_code code, tree type,
7572 ret = fold_build1_loc (gimple_location (gsi_stmt (*gsi)), code, type, a);
7575 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7581 /* Emit return warnings. */
7584 execute_warn_function_return (void)
7586 source_location location;
7591 /* If we have a path to EXIT, then we do return. */
7592 if (TREE_THIS_VOLATILE (cfun->decl)
7593 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0)
7595 location = UNKNOWN_LOCATION;
7596 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7598 last = last_stmt (e->src);
7599 if (gimple_code (last) == GIMPLE_RETURN
7600 && (location = gimple_location (last)) != UNKNOWN_LOCATION)
7603 if (location == UNKNOWN_LOCATION)
7604 location = cfun->function_end_locus;
7605 warning_at (location, 0, "%<noreturn%> function does return");
7608 /* If we see "return;" in some basic block, then we do reach the end
7609 without returning a value. */
7610 else if (warn_return_type
7611 && !TREE_NO_WARNING (cfun->decl)
7612 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0
7613 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (cfun->decl))))
7615 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7617 gimple last = last_stmt (e->src);
7618 if (gimple_code (last) == GIMPLE_RETURN
7619 && gimple_return_retval (last) == NULL
7620 && !gimple_no_warning_p (last))
7622 location = gimple_location (last);
7623 if (location == UNKNOWN_LOCATION)
7624 location = cfun->function_end_locus;
7625 warning_at (location, OPT_Wreturn_type, "control reaches end of non-void function");
7626 TREE_NO_WARNING (cfun->decl) = 1;
7635 /* Given a basic block B which ends with a conditional and has
7636 precisely two successors, determine which of the edges is taken if
7637 the conditional is true and which is taken if the conditional is
7638 false. Set TRUE_EDGE and FALSE_EDGE appropriately. */
7641 extract_true_false_edges_from_block (basic_block b,
7645 edge e = EDGE_SUCC (b, 0);
7647 if (e->flags & EDGE_TRUE_VALUE)
7650 *false_edge = EDGE_SUCC (b, 1);
7655 *true_edge = EDGE_SUCC (b, 1);
7659 struct gimple_opt_pass pass_warn_function_return =
7665 execute_warn_function_return, /* execute */
7668 0, /* static_pass_number */
7669 TV_NONE, /* tv_id */
7670 PROP_cfg, /* properties_required */
7671 0, /* properties_provided */
7672 0, /* properties_destroyed */
7673 0, /* todo_flags_start */
7674 0 /* todo_flags_finish */
7678 /* Emit noreturn warnings. */
7681 execute_warn_function_noreturn (void)
7683 if (warn_missing_noreturn
7684 && !TREE_THIS_VOLATILE (cfun->decl)
7685 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0
7686 && !lang_hooks.missing_noreturn_ok_p (cfun->decl))
7687 warning_at (DECL_SOURCE_LOCATION (cfun->decl), OPT_Wmissing_noreturn,
7688 "function might be possible candidate "
7689 "for attribute %<noreturn%>");
7693 struct gimple_opt_pass pass_warn_function_noreturn =
7699 execute_warn_function_noreturn, /* execute */
7702 0, /* static_pass_number */
7703 TV_NONE, /* tv_id */
7704 PROP_cfg, /* properties_required */
7705 0, /* properties_provided */
7706 0, /* properties_destroyed */
7707 0, /* todo_flags_start */
7708 0 /* todo_flags_finish */
7713 /* Walk a gimplified function and warn for functions whose return value is
7714 ignored and attribute((warn_unused_result)) is set. This is done before
7715 inlining, so we don't have to worry about that. */
7718 do_warn_unused_result (gimple_seq seq)
7721 gimple_stmt_iterator i;
7723 for (i = gsi_start (seq); !gsi_end_p (i); gsi_next (&i))
7725 gimple g = gsi_stmt (i);
7727 switch (gimple_code (g))
7730 do_warn_unused_result (gimple_bind_body (g));
7733 do_warn_unused_result (gimple_try_eval (g));
7734 do_warn_unused_result (gimple_try_cleanup (g));
7737 do_warn_unused_result (gimple_catch_handler (g));
7739 case GIMPLE_EH_FILTER:
7740 do_warn_unused_result (gimple_eh_filter_failure (g));
7744 if (gimple_call_lhs (g))
7747 /* This is a naked call, as opposed to a GIMPLE_CALL with an
7748 LHS. All calls whose value is ignored should be
7749 represented like this. Look for the attribute. */
7750 fdecl = gimple_call_fndecl (g);
7751 ftype = TREE_TYPE (TREE_TYPE (gimple_call_fn (g)));
7753 if (lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (ftype)))
7755 location_t loc = gimple_location (g);
7758 warning_at (loc, OPT_Wunused_result,
7759 "ignoring return value of %qD, "
7760 "declared with attribute warn_unused_result",
7763 warning_at (loc, OPT_Wunused_result,
7764 "ignoring return value of function "
7765 "declared with attribute warn_unused_result");
7770 /* Not a container, not a call, or a call whose value is used. */
7777 run_warn_unused_result (void)
7779 do_warn_unused_result (gimple_body (current_function_decl));
7784 gate_warn_unused_result (void)
7786 return flag_warn_unused_result;
7789 struct gimple_opt_pass pass_warn_unused_result =
7793 "*warn_unused_result", /* name */
7794 gate_warn_unused_result, /* gate */
7795 run_warn_unused_result, /* execute */
7798 0, /* static_pass_number */
7799 TV_NONE, /* tv_id */
7800 PROP_gimple_any, /* properties_required */
7801 0, /* properties_provided */
7802 0, /* properties_destroyed */
7803 0, /* todo_flags_start */
7804 0, /* todo_flags_finish */