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;
2007 /* Otherwise this is a list of cleanup statements. */
2008 remove_useless_stmts_1 (&cleanup_gsi, data);
2010 /* If the cleanup is empty, then we can emit the TRY block without
2011 the enclosing TRY_CATCH_EXPR. */
2012 if (gimple_seq_empty_p (cleanup_seq))
2014 gsi_insert_seq_before (gsi, eval_seq, GSI_SAME_STMT);
2015 gsi_remove(gsi, false);
2016 data->repeat = true;
2023 data->may_throw |= this_may_throw;
2026 /* Helper for remove_useless_stmts_1. Handle GIMPLE_BIND statements. */
2029 remove_useless_stmts_bind (gimple_stmt_iterator *gsi, struct rus_data *data ATTRIBUTE_UNUSED)
2032 gimple_seq body_seq, fn_body_seq;
2033 gimple_stmt_iterator body_gsi;
2035 gimple stmt = gsi_stmt (*gsi);
2037 /* First remove anything underneath the BIND_EXPR. */
2039 body_seq = gimple_bind_body (stmt);
2040 body_gsi = gsi_start (body_seq);
2041 remove_useless_stmts_1 (&body_gsi, data);
2043 /* If the GIMPLE_BIND has no variables, then we can pull everything
2044 up one level and remove the GIMPLE_BIND, unless this is the toplevel
2045 GIMPLE_BIND for the current function or an inlined function.
2047 When this situation occurs we will want to apply this
2048 optimization again. */
2049 block = gimple_bind_block (stmt);
2050 fn_body_seq = gimple_body (current_function_decl);
2051 if (gimple_bind_vars (stmt) == NULL_TREE
2052 && (gimple_seq_empty_p (fn_body_seq)
2053 || stmt != gimple_seq_first_stmt (fn_body_seq))
2055 || ! BLOCK_ABSTRACT_ORIGIN (block)
2056 || (TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block))
2059 tree var = NULL_TREE;
2060 /* Even if there are no gimple_bind_vars, there might be other
2061 decls in BLOCK_VARS rendering the GIMPLE_BIND not useless. */
2062 if (block && !BLOCK_NUM_NONLOCALIZED_VARS (block))
2063 for (var = BLOCK_VARS (block); var; var = TREE_CHAIN (var))
2064 if (TREE_CODE (var) == IMPORTED_DECL)
2066 if (var || (block && BLOCK_NUM_NONLOCALIZED_VARS (block)))
2070 gsi_insert_seq_before (gsi, body_seq, GSI_SAME_STMT);
2071 gsi_remove (gsi, false);
2072 data->repeat = true;
2079 /* Helper for remove_useless_stmts_1. Handle GIMPLE_GOTO statements. */
2082 remove_useless_stmts_goto (gimple_stmt_iterator *gsi, struct rus_data *data)
2084 gimple stmt = gsi_stmt (*gsi);
2086 tree dest = gimple_goto_dest (stmt);
2088 data->may_branch = true;
2089 data->last_was_goto = false;
2091 /* Record iterator for last goto expr, so that we can delete it if unnecessary. */
2092 if (TREE_CODE (dest) == LABEL_DECL)
2094 data->last_goto_gsi = *gsi;
2095 data->last_was_goto = true;
2101 /* Helper for remove_useless_stmts_1. Handle GIMPLE_LABEL statements. */
2104 remove_useless_stmts_label (gimple_stmt_iterator *gsi, struct rus_data *data)
2106 gimple stmt = gsi_stmt (*gsi);
2108 tree label = gimple_label_label (stmt);
2110 data->has_label = true;
2112 /* We do want to jump across non-local label receiver code. */
2113 if (DECL_NONLOCAL (label))
2114 data->last_was_goto = false;
2116 else if (data->last_was_goto
2117 && gimple_goto_dest (gsi_stmt (data->last_goto_gsi)) == label)
2119 /* Replace the preceding GIMPLE_GOTO statement with
2120 a GIMPLE_NOP, which will be subsequently removed.
2121 In this way, we avoid invalidating other iterators
2122 active on the statement sequence. */
2123 gsi_replace(&data->last_goto_gsi, gimple_build_nop(), false);
2124 data->last_was_goto = false;
2125 data->repeat = true;
2128 /* ??? Add something here to delete unused labels. */
2134 /* T is CALL_EXPR. Set current_function_calls_* flags. */
2137 notice_special_calls (gimple call)
2139 int flags = gimple_call_flags (call);
2141 if (flags & ECF_MAY_BE_ALLOCA)
2142 cfun->calls_alloca = true;
2143 if (flags & ECF_RETURNS_TWICE)
2144 cfun->calls_setjmp = true;
2148 /* Clear flags set by notice_special_calls. Used by dead code removal
2149 to update the flags. */
2152 clear_special_calls (void)
2154 cfun->calls_alloca = false;
2155 cfun->calls_setjmp = false;
2158 /* Remove useless statements from a statement sequence, and perform
2159 some preliminary simplifications. */
2162 remove_useless_stmts_1 (gimple_stmt_iterator *gsi, struct rus_data *data)
2164 while (!gsi_end_p (*gsi))
2166 gimple stmt = gsi_stmt (*gsi);
2168 switch (gimple_code (stmt))
2171 remove_useless_stmts_cond (gsi, data);
2175 remove_useless_stmts_goto (gsi, data);
2179 remove_useless_stmts_label (gsi, data);
2184 stmt = gsi_stmt (*gsi);
2185 data->last_was_goto = false;
2186 if (stmt_could_throw_p (stmt))
2187 data->may_throw = true;
2193 data->last_was_goto = false;
2199 stmt = gsi_stmt (*gsi);
2200 data->last_was_goto = false;
2201 if (is_gimple_call (stmt))
2202 notice_special_calls (stmt);
2204 /* We used to call update_gimple_call_flags here,
2205 which copied side-effects and nothrows status
2206 from the function decl to the call. In the new
2207 tuplified GIMPLE, the accessors for this information
2208 always consult the function decl, so this copying
2209 is no longer necessary. */
2210 if (stmt_could_throw_p (stmt))
2211 data->may_throw = true;
2217 data->last_was_goto = false;
2218 data->may_branch = true;
2223 remove_useless_stmts_bind (gsi, data);
2227 if (gimple_try_kind (stmt) == GIMPLE_TRY_CATCH)
2228 remove_useless_stmts_tc (gsi, data);
2229 else if (gimple_try_kind (stmt) == GIMPLE_TRY_FINALLY)
2230 remove_useless_stmts_tf (gsi, data);
2240 gsi_remove (gsi, false);
2243 case GIMPLE_OMP_FOR:
2245 gimple_seq pre_body_seq = gimple_omp_for_pre_body (stmt);
2246 gimple_stmt_iterator pre_body_gsi = gsi_start (pre_body_seq);
2248 remove_useless_stmts_1 (&pre_body_gsi, data);
2249 data->last_was_goto = false;
2252 case GIMPLE_OMP_CRITICAL:
2253 case GIMPLE_OMP_CONTINUE:
2254 case GIMPLE_OMP_MASTER:
2255 case GIMPLE_OMP_ORDERED:
2256 case GIMPLE_OMP_SECTION:
2257 case GIMPLE_OMP_SECTIONS:
2258 case GIMPLE_OMP_SINGLE:
2260 gimple_seq body_seq = gimple_omp_body (stmt);
2261 gimple_stmt_iterator body_gsi = gsi_start (body_seq);
2263 remove_useless_stmts_1 (&body_gsi, data);
2264 data->last_was_goto = false;
2269 case GIMPLE_OMP_PARALLEL:
2270 case GIMPLE_OMP_TASK:
2272 /* Make sure the outermost GIMPLE_BIND isn't removed
2274 gimple_seq body_seq = gimple_omp_body (stmt);
2275 gimple bind = gimple_seq_first_stmt (body_seq);
2276 gimple_seq bind_seq = gimple_bind_body (bind);
2277 gimple_stmt_iterator bind_gsi = gsi_start (bind_seq);
2279 remove_useless_stmts_1 (&bind_gsi, data);
2280 data->last_was_goto = false;
2286 data->last_was_goto = false;
2293 /* Walk the function tree, removing useless statements and performing
2294 some preliminary simplifications. */
2297 remove_useless_stmts (void)
2299 struct rus_data data;
2301 clear_special_calls ();
2305 gimple_stmt_iterator gsi;
2307 gsi = gsi_start (gimple_body (current_function_decl));
2308 memset (&data, 0, sizeof (data));
2309 remove_useless_stmts_1 (&gsi, &data);
2311 while (data.repeat);
2313 #ifdef ENABLE_TYPES_CHECKING
2314 verify_types_in_gimple_seq (gimple_body (current_function_decl));
2321 struct gimple_opt_pass pass_remove_useless_stmts =
2325 "useless", /* name */
2327 remove_useless_stmts, /* execute */
2330 0, /* static_pass_number */
2331 TV_NONE, /* tv_id */
2332 PROP_gimple_any, /* properties_required */
2333 0, /* properties_provided */
2334 0, /* properties_destroyed */
2335 0, /* todo_flags_start */
2336 TODO_dump_func /* todo_flags_finish */
2340 /* Remove PHI nodes associated with basic block BB and all edges out of BB. */
2343 remove_phi_nodes_and_edges_for_unreachable_block (basic_block bb)
2345 /* Since this block is no longer reachable, we can just delete all
2346 of its PHI nodes. */
2347 remove_phi_nodes (bb);
2349 /* Remove edges to BB's successors. */
2350 while (EDGE_COUNT (bb->succs) > 0)
2351 remove_edge (EDGE_SUCC (bb, 0));
2355 /* Remove statements of basic block BB. */
2358 remove_bb (basic_block bb)
2360 gimple_stmt_iterator i;
2361 source_location loc = UNKNOWN_LOCATION;
2365 fprintf (dump_file, "Removing basic block %d\n", bb->index);
2366 if (dump_flags & TDF_DETAILS)
2368 dump_bb (bb, dump_file, 0);
2369 fprintf (dump_file, "\n");
2375 struct loop *loop = bb->loop_father;
2377 /* If a loop gets removed, clean up the information associated
2379 if (loop->latch == bb
2380 || loop->header == bb)
2381 free_numbers_of_iterations_estimates_loop (loop);
2384 /* Remove all the instructions in the block. */
2385 if (bb_seq (bb) != NULL)
2387 /* Walk backwards so as to get a chance to substitute all
2388 released DEFs into debug stmts. See
2389 eliminate_unnecessary_stmts() in tree-ssa-dce.c for more
2391 for (i = gsi_last_bb (bb); !gsi_end_p (i);)
2393 gimple stmt = gsi_stmt (i);
2394 if (gimple_code (stmt) == GIMPLE_LABEL
2395 && (FORCED_LABEL (gimple_label_label (stmt))
2396 || DECL_NONLOCAL (gimple_label_label (stmt))))
2399 gimple_stmt_iterator new_gsi;
2401 /* A non-reachable non-local label may still be referenced.
2402 But it no longer needs to carry the extra semantics of
2404 if (DECL_NONLOCAL (gimple_label_label (stmt)))
2406 DECL_NONLOCAL (gimple_label_label (stmt)) = 0;
2407 FORCED_LABEL (gimple_label_label (stmt)) = 1;
2410 new_bb = bb->prev_bb;
2411 new_gsi = gsi_start_bb (new_bb);
2412 gsi_remove (&i, false);
2413 gsi_insert_before (&new_gsi, stmt, GSI_NEW_STMT);
2417 /* Release SSA definitions if we are in SSA. Note that we
2418 may be called when not in SSA. For example,
2419 final_cleanup calls this function via
2420 cleanup_tree_cfg. */
2421 if (gimple_in_ssa_p (cfun))
2422 release_defs (stmt);
2424 gsi_remove (&i, true);
2428 i = gsi_last_bb (bb);
2432 /* Don't warn for removed gotos. Gotos are often removed due to
2433 jump threading, thus resulting in bogus warnings. Not great,
2434 since this way we lose warnings for gotos in the original
2435 program that are indeed unreachable. */
2436 if (gimple_code (stmt) != GIMPLE_GOTO
2437 && gimple_has_location (stmt))
2438 loc = gimple_location (stmt);
2442 /* If requested, give a warning that the first statement in the
2443 block is unreachable. We walk statements backwards in the
2444 loop above, so the last statement we process is the first statement
2446 if (loc > BUILTINS_LOCATION && LOCATION_LINE (loc) > 0)
2447 warning_at (loc, OPT_Wunreachable_code, "will never be executed");
2449 remove_phi_nodes_and_edges_for_unreachable_block (bb);
2450 bb->il.gimple = NULL;
2454 /* Given a basic block BB ending with COND_EXPR or SWITCH_EXPR, and a
2455 predicate VAL, return the edge that will be taken out of the block.
2456 If VAL does not match a unique edge, NULL is returned. */
2459 find_taken_edge (basic_block bb, tree val)
2463 stmt = last_stmt (bb);
2466 gcc_assert (is_ctrl_stmt (stmt));
2471 if (!is_gimple_min_invariant (val))
2474 if (gimple_code (stmt) == GIMPLE_COND)
2475 return find_taken_edge_cond_expr (bb, val);
2477 if (gimple_code (stmt) == GIMPLE_SWITCH)
2478 return find_taken_edge_switch_expr (bb, val);
2480 if (computed_goto_p (stmt))
2482 /* Only optimize if the argument is a label, if the argument is
2483 not a label then we can not construct a proper CFG.
2485 It may be the case that we only need to allow the LABEL_REF to
2486 appear inside an ADDR_EXPR, but we also allow the LABEL_REF to
2487 appear inside a LABEL_EXPR just to be safe. */
2488 if ((TREE_CODE (val) == ADDR_EXPR || TREE_CODE (val) == LABEL_EXPR)
2489 && TREE_CODE (TREE_OPERAND (val, 0)) == LABEL_DECL)
2490 return find_taken_edge_computed_goto (bb, TREE_OPERAND (val, 0));
2497 /* Given a constant value VAL and the entry block BB to a GOTO_EXPR
2498 statement, determine which of the outgoing edges will be taken out of the
2499 block. Return NULL if either edge may be taken. */
2502 find_taken_edge_computed_goto (basic_block bb, tree val)
2507 dest = label_to_block (val);
2510 e = find_edge (bb, dest);
2511 gcc_assert (e != NULL);
2517 /* Given a constant value VAL and the entry block BB to a COND_EXPR
2518 statement, determine which of the two edges will be taken out of the
2519 block. Return NULL if either edge may be taken. */
2522 find_taken_edge_cond_expr (basic_block bb, tree val)
2524 edge true_edge, false_edge;
2526 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
2528 gcc_assert (TREE_CODE (val) == INTEGER_CST);
2529 return (integer_zerop (val) ? false_edge : true_edge);
2532 /* Given an INTEGER_CST VAL and the entry block BB to a SWITCH_EXPR
2533 statement, determine which edge will be taken out of the block. Return
2534 NULL if any edge may be taken. */
2537 find_taken_edge_switch_expr (basic_block bb, tree val)
2539 basic_block dest_bb;
2544 switch_stmt = last_stmt (bb);
2545 taken_case = find_case_label_for_value (switch_stmt, val);
2546 dest_bb = label_to_block (CASE_LABEL (taken_case));
2548 e = find_edge (bb, dest_bb);
2554 /* Return the CASE_LABEL_EXPR that SWITCH_STMT will take for VAL.
2555 We can make optimal use here of the fact that the case labels are
2556 sorted: We can do a binary search for a case matching VAL. */
2559 find_case_label_for_value (gimple switch_stmt, tree val)
2561 size_t low, high, n = gimple_switch_num_labels (switch_stmt);
2562 tree default_case = gimple_switch_default_label (switch_stmt);
2564 for (low = 0, high = n; high - low > 1; )
2566 size_t i = (high + low) / 2;
2567 tree t = gimple_switch_label (switch_stmt, i);
2570 /* Cache the result of comparing CASE_LOW and val. */
2571 cmp = tree_int_cst_compare (CASE_LOW (t), val);
2578 if (CASE_HIGH (t) == NULL)
2580 /* A singe-valued case label. */
2586 /* A case range. We can only handle integer ranges. */
2587 if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
2592 return default_case;
2596 /* Dump a basic block on stderr. */
2599 gimple_debug_bb (basic_block bb)
2601 gimple_dump_bb (bb, stderr, 0, TDF_VOPS|TDF_MEMSYMS);
2605 /* Dump basic block with index N on stderr. */
2608 gimple_debug_bb_n (int n)
2610 gimple_debug_bb (BASIC_BLOCK (n));
2611 return BASIC_BLOCK (n);
2615 /* Dump the CFG on stderr.
2617 FLAGS are the same used by the tree dumping functions
2618 (see TDF_* in tree-pass.h). */
2621 gimple_debug_cfg (int flags)
2623 gimple_dump_cfg (stderr, flags);
2627 /* Dump the program showing basic block boundaries on the given FILE.
2629 FLAGS are the same used by the tree dumping functions (see TDF_* in
2633 gimple_dump_cfg (FILE *file, int flags)
2635 if (flags & TDF_DETAILS)
2637 const char *funcname
2638 = lang_hooks.decl_printable_name (current_function_decl, 2);
2641 fprintf (file, ";; Function %s\n\n", funcname);
2642 fprintf (file, ";; \n%d basic blocks, %d edges, last basic block %d.\n\n",
2643 n_basic_blocks, n_edges, last_basic_block);
2645 brief_dump_cfg (file);
2646 fprintf (file, "\n");
2649 if (flags & TDF_STATS)
2650 dump_cfg_stats (file);
2652 dump_function_to_file (current_function_decl, file, flags | TDF_BLOCKS);
2656 /* Dump CFG statistics on FILE. */
2659 dump_cfg_stats (FILE *file)
2661 static long max_num_merged_labels = 0;
2662 unsigned long size, total = 0;
2665 const char * const fmt_str = "%-30s%-13s%12s\n";
2666 const char * const fmt_str_1 = "%-30s%13d%11lu%c\n";
2667 const char * const fmt_str_2 = "%-30s%13ld%11lu%c\n";
2668 const char * const fmt_str_3 = "%-43s%11lu%c\n";
2669 const char *funcname
2670 = lang_hooks.decl_printable_name (current_function_decl, 2);
2673 fprintf (file, "\nCFG Statistics for %s\n\n", funcname);
2675 fprintf (file, "---------------------------------------------------------\n");
2676 fprintf (file, fmt_str, "", " Number of ", "Memory");
2677 fprintf (file, fmt_str, "", " instances ", "used ");
2678 fprintf (file, "---------------------------------------------------------\n");
2680 size = n_basic_blocks * sizeof (struct basic_block_def);
2682 fprintf (file, fmt_str_1, "Basic blocks", n_basic_blocks,
2683 SCALE (size), LABEL (size));
2687 num_edges += EDGE_COUNT (bb->succs);
2688 size = num_edges * sizeof (struct edge_def);
2690 fprintf (file, fmt_str_2, "Edges", num_edges, SCALE (size), LABEL (size));
2692 fprintf (file, "---------------------------------------------------------\n");
2693 fprintf (file, fmt_str_3, "Total memory used by CFG data", SCALE (total),
2695 fprintf (file, "---------------------------------------------------------\n");
2696 fprintf (file, "\n");
2698 if (cfg_stats.num_merged_labels > max_num_merged_labels)
2699 max_num_merged_labels = cfg_stats.num_merged_labels;
2701 fprintf (file, "Coalesced label blocks: %ld (Max so far: %ld)\n",
2702 cfg_stats.num_merged_labels, max_num_merged_labels);
2704 fprintf (file, "\n");
2708 /* Dump CFG statistics on stderr. Keep extern so that it's always
2709 linked in the final executable. */
2712 debug_cfg_stats (void)
2714 dump_cfg_stats (stderr);
2718 /* Dump the flowgraph to a .vcg FILE. */
2721 gimple_cfg2vcg (FILE *file)
2726 const char *funcname
2727 = lang_hooks.decl_printable_name (current_function_decl, 2);
2729 /* Write the file header. */
2730 fprintf (file, "graph: { title: \"%s\"\n", funcname);
2731 fprintf (file, "node: { title: \"ENTRY\" label: \"ENTRY\" }\n");
2732 fprintf (file, "node: { title: \"EXIT\" label: \"EXIT\" }\n");
2734 /* Write blocks and edges. */
2735 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
2737 fprintf (file, "edge: { sourcename: \"ENTRY\" targetname: \"%d\"",
2740 if (e->flags & EDGE_FAKE)
2741 fprintf (file, " linestyle: dotted priority: 10");
2743 fprintf (file, " linestyle: solid priority: 100");
2745 fprintf (file, " }\n");
2751 enum gimple_code head_code, end_code;
2752 const char *head_name, *end_name;
2755 gimple first = first_stmt (bb);
2756 gimple last = last_stmt (bb);
2760 head_code = gimple_code (first);
2761 head_name = gimple_code_name[head_code];
2762 head_line = get_lineno (first);
2765 head_name = "no-statement";
2769 end_code = gimple_code (last);
2770 end_name = gimple_code_name[end_code];
2771 end_line = get_lineno (last);
2774 end_name = "no-statement";
2776 fprintf (file, "node: { title: \"%d\" label: \"#%d\\n%s (%d)\\n%s (%d)\"}\n",
2777 bb->index, bb->index, head_name, head_line, end_name,
2780 FOR_EACH_EDGE (e, ei, bb->succs)
2782 if (e->dest == EXIT_BLOCK_PTR)
2783 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"EXIT\"", bb->index);
2785 fprintf (file, "edge: { sourcename: \"%d\" targetname: \"%d\"", bb->index, e->dest->index);
2787 if (e->flags & EDGE_FAKE)
2788 fprintf (file, " priority: 10 linestyle: dotted");
2790 fprintf (file, " priority: 100 linestyle: solid");
2792 fprintf (file, " }\n");
2795 if (bb->next_bb != EXIT_BLOCK_PTR)
2799 fputs ("}\n\n", file);
2804 /*---------------------------------------------------------------------------
2805 Miscellaneous helpers
2806 ---------------------------------------------------------------------------*/
2808 /* Return true if T represents a stmt that always transfers control. */
2811 is_ctrl_stmt (gimple t)
2813 switch (gimple_code (t))
2827 /* Return true if T is a statement that may alter the flow of control
2828 (e.g., a call to a non-returning function). */
2831 is_ctrl_altering_stmt (gimple t)
2835 switch (gimple_code (t))
2839 int flags = gimple_call_flags (t);
2841 /* A non-pure/const call alters flow control if the current
2842 function has nonlocal labels. */
2843 if (!(flags & (ECF_CONST | ECF_PURE)) && cfun->has_nonlocal_label)
2846 /* A call also alters control flow if it does not return. */
2847 if (gimple_call_flags (t) & ECF_NORETURN)
2852 case GIMPLE_EH_DISPATCH:
2853 /* EH_DISPATCH branches to the individual catch handlers at
2854 this level of a try or allowed-exceptions region. It can
2855 fallthru to the next statement as well. */
2859 if (gimple_asm_nlabels (t) > 0)
2864 /* OpenMP directives alter control flow. */
2871 /* If a statement can throw, it alters control flow. */
2872 return stmt_can_throw_internal (t);
2876 /* Return true if T is a simple local goto. */
2879 simple_goto_p (gimple t)
2881 return (gimple_code (t) == GIMPLE_GOTO
2882 && TREE_CODE (gimple_goto_dest (t)) == LABEL_DECL);
2886 /* Return true if T can make an abnormal transfer of control flow.
2887 Transfers of control flow associated with EH are excluded. */
2890 stmt_can_make_abnormal_goto (gimple t)
2892 if (computed_goto_p (t))
2894 if (is_gimple_call (t))
2895 return gimple_has_side_effects (t) && cfun->has_nonlocal_label;
2900 /* Return true if STMT should start a new basic block. PREV_STMT is
2901 the statement preceding STMT. It is used when STMT is a label or a
2902 case label. Labels should only start a new basic block if their
2903 previous statement wasn't a label. Otherwise, sequence of labels
2904 would generate unnecessary basic blocks that only contain a single
2908 stmt_starts_bb_p (gimple stmt, gimple prev_stmt)
2913 /* Labels start a new basic block only if the preceding statement
2914 wasn't a label of the same type. This prevents the creation of
2915 consecutive blocks that have nothing but a single label. */
2916 if (gimple_code (stmt) == GIMPLE_LABEL)
2918 /* Nonlocal and computed GOTO targets always start a new block. */
2919 if (DECL_NONLOCAL (gimple_label_label (stmt))
2920 || FORCED_LABEL (gimple_label_label (stmt)))
2923 if (prev_stmt && gimple_code (prev_stmt) == GIMPLE_LABEL)
2925 if (DECL_NONLOCAL (gimple_label_label (prev_stmt)))
2928 cfg_stats.num_merged_labels++;
2939 /* Return true if T should end a basic block. */
2942 stmt_ends_bb_p (gimple t)
2944 return is_ctrl_stmt (t) || is_ctrl_altering_stmt (t);
2947 /* Remove block annotations and other data structures. */
2950 delete_tree_cfg_annotations (void)
2952 label_to_block_map = NULL;
2956 /* Return the first statement in basic block BB. */
2959 first_stmt (basic_block bb)
2961 gimple_stmt_iterator i = gsi_start_bb (bb);
2964 while (!gsi_end_p (i) && is_gimple_debug ((stmt = gsi_stmt (i))))
2972 /* Return the first non-label statement in basic block BB. */
2975 first_non_label_stmt (basic_block bb)
2977 gimple_stmt_iterator i = gsi_start_bb (bb);
2978 while (!gsi_end_p (i) && gimple_code (gsi_stmt (i)) == GIMPLE_LABEL)
2980 return !gsi_end_p (i) ? gsi_stmt (i) : NULL;
2983 /* Return the last statement in basic block BB. */
2986 last_stmt (basic_block bb)
2988 gimple_stmt_iterator i = gsi_last_bb (bb);
2991 while (!gsi_end_p (i) && is_gimple_debug ((stmt = gsi_stmt (i))))
2999 /* Return the last statement of an otherwise empty block. Return NULL
3000 if the block is totally empty, or if it contains more than one
3004 last_and_only_stmt (basic_block bb)
3006 gimple_stmt_iterator i = gsi_last_nondebug_bb (bb);
3012 last = gsi_stmt (i);
3013 gsi_prev_nondebug (&i);
3017 /* Empty statements should no longer appear in the instruction stream.
3018 Everything that might have appeared before should be deleted by
3019 remove_useless_stmts, and the optimizers should just gsi_remove
3020 instead of smashing with build_empty_stmt.
3022 Thus the only thing that should appear here in a block containing
3023 one executable statement is a label. */
3024 prev = gsi_stmt (i);
3025 if (gimple_code (prev) == GIMPLE_LABEL)
3031 /* Reinstall those PHI arguments queued in OLD_EDGE to NEW_EDGE. */
3034 reinstall_phi_args (edge new_edge, edge old_edge)
3036 edge_var_map_vector v;
3039 gimple_stmt_iterator phis;
3041 v = redirect_edge_var_map_vector (old_edge);
3045 for (i = 0, phis = gsi_start_phis (new_edge->dest);
3046 VEC_iterate (edge_var_map, v, i, vm) && !gsi_end_p (phis);
3047 i++, gsi_next (&phis))
3049 gimple phi = gsi_stmt (phis);
3050 tree result = redirect_edge_var_map_result (vm);
3051 tree arg = redirect_edge_var_map_def (vm);
3053 gcc_assert (result == gimple_phi_result (phi));
3055 add_phi_arg (phi, arg, new_edge, redirect_edge_var_map_location (vm));
3058 redirect_edge_var_map_clear (old_edge);
3061 /* Returns the basic block after which the new basic block created
3062 by splitting edge EDGE_IN should be placed. Tries to keep the new block
3063 near its "logical" location. This is of most help to humans looking
3064 at debugging dumps. */
3067 split_edge_bb_loc (edge edge_in)
3069 basic_block dest = edge_in->dest;
3070 basic_block dest_prev = dest->prev_bb;
3074 edge e = find_edge (dest_prev, dest);
3075 if (e && !(e->flags & EDGE_COMPLEX))
3076 return edge_in->src;
3081 /* Split a (typically critical) edge EDGE_IN. Return the new block.
3082 Abort on abnormal edges. */
3085 gimple_split_edge (edge edge_in)
3087 basic_block new_bb, after_bb, dest;
3090 /* Abnormal edges cannot be split. */
3091 gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
3093 dest = edge_in->dest;
3095 after_bb = split_edge_bb_loc (edge_in);
3097 new_bb = create_empty_bb (after_bb);
3098 new_bb->frequency = EDGE_FREQUENCY (edge_in);
3099 new_bb->count = edge_in->count;
3100 new_edge = make_edge (new_bb, dest, EDGE_FALLTHRU);
3101 new_edge->probability = REG_BR_PROB_BASE;
3102 new_edge->count = edge_in->count;
3104 e = redirect_edge_and_branch (edge_in, new_bb);
3105 gcc_assert (e == edge_in);
3106 reinstall_phi_args (new_edge, e);
3111 /* Callback for walk_tree, check that all elements with address taken are
3112 properly noticed as such. The DATA is an int* that is 1 if TP was seen
3113 inside a PHI node. */
3116 verify_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
3123 /* Check operand N for being valid GIMPLE and give error MSG if not. */
3124 #define CHECK_OP(N, MSG) \
3125 do { if (!is_gimple_val (TREE_OPERAND (t, N))) \
3126 { error (MSG); return TREE_OPERAND (t, N); }} while (0)
3128 switch (TREE_CODE (t))
3131 if (SSA_NAME_IN_FREE_LIST (t))
3133 error ("SSA name in freelist but still referenced");
3139 x = TREE_OPERAND (t, 0);
3140 if (!is_gimple_reg (x) && !is_gimple_min_invariant (x))
3142 error ("Indirect reference's operand is not a register or a constant.");
3148 x = fold (ASSERT_EXPR_COND (t));
3149 if (x == boolean_false_node)
3151 error ("ASSERT_EXPR with an always-false condition");
3157 error ("MODIFY_EXPR not expected while having tuples.");
3163 bool old_side_effects;
3165 bool new_side_effects;
3167 gcc_assert (is_gimple_address (t));
3169 old_constant = TREE_CONSTANT (t);
3170 old_side_effects = TREE_SIDE_EFFECTS (t);
3172 recompute_tree_invariant_for_addr_expr (t);
3173 new_side_effects = TREE_SIDE_EFFECTS (t);
3174 new_constant = TREE_CONSTANT (t);
3176 if (old_constant != new_constant)
3178 error ("constant not recomputed when ADDR_EXPR changed");
3181 if (old_side_effects != new_side_effects)
3183 error ("side effects not recomputed when ADDR_EXPR changed");
3187 /* Skip any references (they will be checked when we recurse down the
3188 tree) and ensure that any variable used as a prefix is marked
3190 for (x = TREE_OPERAND (t, 0);
3191 handled_component_p (x);
3192 x = TREE_OPERAND (x, 0))
3195 if (!(TREE_CODE (x) == VAR_DECL
3196 || TREE_CODE (x) == PARM_DECL
3197 || TREE_CODE (x) == RESULT_DECL))
3199 if (!TREE_ADDRESSABLE (x))
3201 error ("address taken, but ADDRESSABLE bit not set");
3204 if (DECL_GIMPLE_REG_P (x))
3206 error ("DECL_GIMPLE_REG_P set on a variable with address taken");
3214 x = COND_EXPR_COND (t);
3215 if (!INTEGRAL_TYPE_P (TREE_TYPE (x)))
3217 error ("non-integral used in condition");
3220 if (!is_gimple_condexpr (x))
3222 error ("invalid conditional operand");
3227 case NON_LVALUE_EXPR:
3231 case FIX_TRUNC_EXPR:
3236 case TRUTH_NOT_EXPR:
3237 CHECK_OP (0, "invalid operand to unary operator");
3244 case ARRAY_RANGE_REF:
3246 case VIEW_CONVERT_EXPR:
3247 /* We have a nest of references. Verify that each of the operands
3248 that determine where to reference is either a constant or a variable,
3249 verify that the base is valid, and then show we've already checked
3251 while (handled_component_p (t))
3253 if (TREE_CODE (t) == COMPONENT_REF && TREE_OPERAND (t, 2))
3254 CHECK_OP (2, "invalid COMPONENT_REF offset operator");
3255 else if (TREE_CODE (t) == ARRAY_REF
3256 || TREE_CODE (t) == ARRAY_RANGE_REF)
3258 CHECK_OP (1, "invalid array index");
3259 if (TREE_OPERAND (t, 2))
3260 CHECK_OP (2, "invalid array lower bound");
3261 if (TREE_OPERAND (t, 3))
3262 CHECK_OP (3, "invalid array stride");
3264 else if (TREE_CODE (t) == BIT_FIELD_REF)
3266 if (!host_integerp (TREE_OPERAND (t, 1), 1)
3267 || !host_integerp (TREE_OPERAND (t, 2), 1))
3269 error ("invalid position or size operand to BIT_FIELD_REF");
3272 else if (INTEGRAL_TYPE_P (TREE_TYPE (t))
3273 && (TYPE_PRECISION (TREE_TYPE (t))
3274 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
3276 error ("integral result type precision does not match "
3277 "field size of BIT_FIELD_REF");
3280 if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
3281 && (GET_MODE_PRECISION (TYPE_MODE (TREE_TYPE (t)))
3282 != TREE_INT_CST_LOW (TREE_OPERAND (t, 1))))
3284 error ("mode precision of non-integral result does not "
3285 "match field size of BIT_FIELD_REF");
3290 t = TREE_OPERAND (t, 0);
3293 if (!is_gimple_min_invariant (t) && !is_gimple_lvalue (t))
3295 error ("invalid reference prefix");
3302 /* PLUS_EXPR and MINUS_EXPR don't work on pointers, they should be done using
3303 POINTER_PLUS_EXPR. */
3304 if (POINTER_TYPE_P (TREE_TYPE (t)))
3306 error ("invalid operand to plus/minus, type is a pointer");
3309 CHECK_OP (0, "invalid operand to binary operator");
3310 CHECK_OP (1, "invalid operand to binary operator");
3313 case POINTER_PLUS_EXPR:
3314 /* Check to make sure the first operand is a pointer or reference type. */
3315 if (!POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 0))))
3317 error ("invalid operand to pointer plus, first operand is not a pointer");
3320 /* Check to make sure the second operand is an integer with type of
3322 if (!useless_type_conversion_p (sizetype,
3323 TREE_TYPE (TREE_OPERAND (t, 1))))
3325 error ("invalid operand to pointer plus, second operand is not an "
3326 "integer with type of sizetype.");
3336 case UNORDERED_EXPR:
3345 case TRUNC_DIV_EXPR:
3347 case FLOOR_DIV_EXPR:
3348 case ROUND_DIV_EXPR:
3349 case TRUNC_MOD_EXPR:
3351 case FLOOR_MOD_EXPR:
3352 case ROUND_MOD_EXPR:
3354 case EXACT_DIV_EXPR:
3364 CHECK_OP (0, "invalid operand to binary operator");
3365 CHECK_OP (1, "invalid operand to binary operator");
3369 if (TREE_CONSTANT (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
3382 /* Verify if EXPR is either a GIMPLE ID or a GIMPLE indirect reference.
3383 Returns true if there is an error, otherwise false. */
3386 verify_types_in_gimple_min_lval (tree expr)
3390 if (is_gimple_id (expr))
3393 if (!INDIRECT_REF_P (expr)
3394 && TREE_CODE (expr) != TARGET_MEM_REF)
3396 error ("invalid expression for min lvalue");
3400 /* TARGET_MEM_REFs are strange beasts. */
3401 if (TREE_CODE (expr) == TARGET_MEM_REF)
3404 op = TREE_OPERAND (expr, 0);
3405 if (!is_gimple_val (op))
3407 error ("invalid operand in indirect reference");
3408 debug_generic_stmt (op);
3411 if (!useless_type_conversion_p (TREE_TYPE (expr),
3412 TREE_TYPE (TREE_TYPE (op))))
3414 error ("type mismatch in indirect reference");
3415 debug_generic_stmt (TREE_TYPE (expr));
3416 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3423 /* Verify if EXPR is a valid GIMPLE reference expression. If
3424 REQUIRE_LVALUE is true verifies it is an lvalue. Returns true
3425 if there is an error, otherwise false. */
3428 verify_types_in_gimple_reference (tree expr, bool require_lvalue)
3430 while (handled_component_p (expr))
3432 tree op = TREE_OPERAND (expr, 0);
3434 if (TREE_CODE (expr) == ARRAY_REF
3435 || TREE_CODE (expr) == ARRAY_RANGE_REF)
3437 if (!is_gimple_val (TREE_OPERAND (expr, 1))
3438 || (TREE_OPERAND (expr, 2)
3439 && !is_gimple_val (TREE_OPERAND (expr, 2)))
3440 || (TREE_OPERAND (expr, 3)
3441 && !is_gimple_val (TREE_OPERAND (expr, 3))))
3443 error ("invalid operands to array reference");
3444 debug_generic_stmt (expr);
3449 /* Verify if the reference array element types are compatible. */
3450 if (TREE_CODE (expr) == ARRAY_REF
3451 && !useless_type_conversion_p (TREE_TYPE (expr),
3452 TREE_TYPE (TREE_TYPE (op))))
3454 error ("type mismatch in array reference");
3455 debug_generic_stmt (TREE_TYPE (expr));
3456 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3459 if (TREE_CODE (expr) == ARRAY_RANGE_REF
3460 && !useless_type_conversion_p (TREE_TYPE (TREE_TYPE (expr)),
3461 TREE_TYPE (TREE_TYPE (op))))
3463 error ("type mismatch in array range reference");
3464 debug_generic_stmt (TREE_TYPE (TREE_TYPE (expr)));
3465 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3469 if ((TREE_CODE (expr) == REALPART_EXPR
3470 || TREE_CODE (expr) == IMAGPART_EXPR)
3471 && !useless_type_conversion_p (TREE_TYPE (expr),
3472 TREE_TYPE (TREE_TYPE (op))))
3474 error ("type mismatch in real/imagpart reference");
3475 debug_generic_stmt (TREE_TYPE (expr));
3476 debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3480 if (TREE_CODE (expr) == COMPONENT_REF
3481 && !useless_type_conversion_p (TREE_TYPE (expr),
3482 TREE_TYPE (TREE_OPERAND (expr, 1))))
3484 error ("type mismatch in component reference");
3485 debug_generic_stmt (TREE_TYPE (expr));
3486 debug_generic_stmt (TREE_TYPE (TREE_OPERAND (expr, 1)));
3490 /* For VIEW_CONVERT_EXPRs which are allowed here, too, there
3491 is nothing to verify. Gross mismatches at most invoke
3492 undefined behavior. */
3493 if (TREE_CODE (expr) == VIEW_CONVERT_EXPR
3494 && !handled_component_p (op))
3500 return ((require_lvalue || !is_gimple_min_invariant (expr))
3501 && verify_types_in_gimple_min_lval (expr));
3504 /* Returns true if there is one pointer type in TYPE_POINTER_TO (SRC_OBJ)
3505 list of pointer-to types that is trivially convertible to DEST. */
3508 one_pointer_to_useless_type_conversion_p (tree dest, tree src_obj)
3512 if (!TYPE_POINTER_TO (src_obj))
3515 for (src = TYPE_POINTER_TO (src_obj); src; src = TYPE_NEXT_PTR_TO (src))
3516 if (useless_type_conversion_p (dest, src))
3522 /* Return true if TYPE1 is a fixed-point type and if conversions to and
3523 from TYPE2 can be handled by FIXED_CONVERT_EXPR. */
3526 valid_fixed_convert_types_p (tree type1, tree type2)
3528 return (FIXED_POINT_TYPE_P (type1)
3529 && (INTEGRAL_TYPE_P (type2)
3530 || SCALAR_FLOAT_TYPE_P (type2)
3531 || FIXED_POINT_TYPE_P (type2)));
3534 /* Verify the contents of a GIMPLE_CALL STMT. Returns true when there
3535 is a problem, otherwise false. */
3538 verify_gimple_call (gimple stmt)
3540 tree fn = gimple_call_fn (stmt);
3543 if (!POINTER_TYPE_P (TREE_TYPE (fn))
3544 || (TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != FUNCTION_TYPE
3545 && TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != METHOD_TYPE))
3547 error ("non-function in gimple call");
3551 if (gimple_call_lhs (stmt)
3552 && !is_gimple_lvalue (gimple_call_lhs (stmt)))
3554 error ("invalid LHS in gimple call");
3558 fntype = TREE_TYPE (TREE_TYPE (fn));
3559 if (gimple_call_lhs (stmt)
3560 && !useless_type_conversion_p (TREE_TYPE (gimple_call_lhs (stmt)),
3562 /* ??? At least C++ misses conversions at assignments from
3563 void * call results.
3564 ??? Java is completely off. Especially with functions
3565 returning java.lang.Object.
3566 For now simply allow arbitrary pointer type conversions. */
3567 && !(POINTER_TYPE_P (TREE_TYPE (gimple_call_lhs (stmt)))
3568 && POINTER_TYPE_P (TREE_TYPE (fntype))))
3570 error ("invalid conversion in gimple call");
3571 debug_generic_stmt (TREE_TYPE (gimple_call_lhs (stmt)));
3572 debug_generic_stmt (TREE_TYPE (fntype));
3576 /* If there is a static chain argument, this should not be an indirect
3577 call, and the decl should not have DECL_NO_STATIC_CHAIN set. */
3578 if (gimple_call_chain (stmt))
3580 if (TREE_CODE (fn) != ADDR_EXPR
3581 || TREE_CODE (TREE_OPERAND (fn, 0)) != FUNCTION_DECL)
3583 error ("static chain in indirect gimple call");
3586 fn = TREE_OPERAND (fn, 0);
3588 if (DECL_NO_STATIC_CHAIN (fn))
3590 error ("static chain with function that doesn't use one");
3595 /* ??? The C frontend passes unpromoted arguments in case it
3596 didn't see a function declaration before the call. So for now
3597 leave the call arguments unverified. Once we gimplify
3598 unit-at-a-time we have a chance to fix this. */
3603 /* Verifies the gimple comparison with the result type TYPE and
3604 the operands OP0 and OP1. */
3607 verify_gimple_comparison (tree type, tree op0, tree op1)
3609 tree op0_type = TREE_TYPE (op0);
3610 tree op1_type = TREE_TYPE (op1);
3612 if (!is_gimple_val (op0) || !is_gimple_val (op1))
3614 error ("invalid operands in gimple comparison");
3618 /* For comparisons we do not have the operations type as the
3619 effective type the comparison is carried out in. Instead
3620 we require that either the first operand is trivially
3621 convertible into the second, or the other way around.
3622 The resulting type of a comparison may be any integral type.
3623 Because we special-case pointers to void we allow
3624 comparisons of pointers with the same mode as well. */
3625 if ((!useless_type_conversion_p (op0_type, op1_type)
3626 && !useless_type_conversion_p (op1_type, op0_type)
3627 && (!POINTER_TYPE_P (op0_type)
3628 || !POINTER_TYPE_P (op1_type)
3629 || TYPE_MODE (op0_type) != TYPE_MODE (op1_type)))
3630 || !INTEGRAL_TYPE_P (type))
3632 error ("type mismatch in comparison expression");
3633 debug_generic_expr (type);
3634 debug_generic_expr (op0_type);
3635 debug_generic_expr (op1_type);
3642 /* Verify a gimple assignment statement STMT with an unary rhs.
3643 Returns true if anything is wrong. */
3646 verify_gimple_assign_unary (gimple stmt)
3648 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3649 tree lhs = gimple_assign_lhs (stmt);
3650 tree lhs_type = TREE_TYPE (lhs);
3651 tree rhs1 = gimple_assign_rhs1 (stmt);
3652 tree rhs1_type = TREE_TYPE (rhs1);
3654 if (!is_gimple_reg (lhs)
3656 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3658 error ("non-register as LHS of unary operation");
3662 if (!is_gimple_val (rhs1))
3664 error ("invalid operand in unary operation");
3668 /* First handle conversions. */
3673 /* Allow conversions between integral types and pointers only if
3674 there is no sign or zero extension involved.
3675 For targets were the precision of sizetype doesn't match that
3676 of pointers we need to allow arbitrary conversions from and
3678 if ((POINTER_TYPE_P (lhs_type)
3679 && INTEGRAL_TYPE_P (rhs1_type)
3680 && (TYPE_PRECISION (lhs_type) >= TYPE_PRECISION (rhs1_type)
3681 || rhs1_type == sizetype))
3682 || (POINTER_TYPE_P (rhs1_type)
3683 && INTEGRAL_TYPE_P (lhs_type)
3684 && (TYPE_PRECISION (rhs1_type) >= TYPE_PRECISION (lhs_type)
3685 || lhs_type == sizetype)))
3688 /* Allow conversion from integer to offset type and vice versa. */
3689 if ((TREE_CODE (lhs_type) == OFFSET_TYPE
3690 && TREE_CODE (rhs1_type) == INTEGER_TYPE)
3691 || (TREE_CODE (lhs_type) == INTEGER_TYPE
3692 && TREE_CODE (rhs1_type) == OFFSET_TYPE))
3695 /* Otherwise assert we are converting between types of the
3697 if (INTEGRAL_TYPE_P (lhs_type) != INTEGRAL_TYPE_P (rhs1_type))
3699 error ("invalid types in nop conversion");
3700 debug_generic_expr (lhs_type);
3701 debug_generic_expr (rhs1_type);
3708 case FIXED_CONVERT_EXPR:
3710 if (!valid_fixed_convert_types_p (lhs_type, rhs1_type)
3711 && !valid_fixed_convert_types_p (rhs1_type, lhs_type))
3713 error ("invalid types in fixed-point conversion");
3714 debug_generic_expr (lhs_type);
3715 debug_generic_expr (rhs1_type);
3724 if (!INTEGRAL_TYPE_P (rhs1_type) || !SCALAR_FLOAT_TYPE_P (lhs_type))
3726 error ("invalid types in conversion to floating point");
3727 debug_generic_expr (lhs_type);
3728 debug_generic_expr (rhs1_type);
3735 case FIX_TRUNC_EXPR:
3737 if (!INTEGRAL_TYPE_P (lhs_type) || !SCALAR_FLOAT_TYPE_P (rhs1_type))
3739 error ("invalid types in conversion to integer");
3740 debug_generic_expr (lhs_type);
3741 debug_generic_expr (rhs1_type);
3748 case VEC_UNPACK_HI_EXPR:
3749 case VEC_UNPACK_LO_EXPR:
3750 case REDUC_MAX_EXPR:
3751 case REDUC_MIN_EXPR:
3752 case REDUC_PLUS_EXPR:
3753 case VEC_UNPACK_FLOAT_HI_EXPR:
3754 case VEC_UNPACK_FLOAT_LO_EXPR:
3758 case TRUTH_NOT_EXPR:
3763 case NON_LVALUE_EXPR:
3771 /* For the remaining codes assert there is no conversion involved. */
3772 if (!useless_type_conversion_p (lhs_type, rhs1_type))
3774 error ("non-trivial conversion in unary operation");
3775 debug_generic_expr (lhs_type);
3776 debug_generic_expr (rhs1_type);
3783 /* Verify a gimple assignment statement STMT with a binary rhs.
3784 Returns true if anything is wrong. */
3787 verify_gimple_assign_binary (gimple stmt)
3789 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3790 tree lhs = gimple_assign_lhs (stmt);
3791 tree lhs_type = TREE_TYPE (lhs);
3792 tree rhs1 = gimple_assign_rhs1 (stmt);
3793 tree rhs1_type = TREE_TYPE (rhs1);
3794 tree rhs2 = gimple_assign_rhs2 (stmt);
3795 tree rhs2_type = TREE_TYPE (rhs2);
3797 if (!is_gimple_reg (lhs)
3799 && TREE_CODE (lhs_type) == COMPLEX_TYPE))
3801 error ("non-register as LHS of binary operation");
3805 if (!is_gimple_val (rhs1)
3806 || !is_gimple_val (rhs2))
3808 error ("invalid operands in binary operation");
3812 /* First handle operations that involve different types. */
3817 if (TREE_CODE (lhs_type) != COMPLEX_TYPE
3818 || !(INTEGRAL_TYPE_P (rhs1_type)
3819 || SCALAR_FLOAT_TYPE_P (rhs1_type))
3820 || !(INTEGRAL_TYPE_P (rhs2_type)
3821 || SCALAR_FLOAT_TYPE_P (rhs2_type)))
3823 error ("type mismatch in complex expression");
3824 debug_generic_expr (lhs_type);
3825 debug_generic_expr (rhs1_type);
3826 debug_generic_expr (rhs2_type);
3838 /* Shifts and rotates are ok on integral types, fixed point
3839 types and integer vector types. */
3840 if ((!INTEGRAL_TYPE_P (rhs1_type)
3841 && !FIXED_POINT_TYPE_P (rhs1_type)
3842 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3843 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE))
3844 || (!INTEGRAL_TYPE_P (rhs2_type)
3845 /* Vector shifts of vectors are also ok. */
3846 && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
3847 && TREE_CODE (TREE_TYPE (rhs1_type)) == INTEGER_TYPE
3848 && TREE_CODE (rhs2_type) == VECTOR_TYPE
3849 && TREE_CODE (TREE_TYPE (rhs2_type)) == INTEGER_TYPE))
3850 || !useless_type_conversion_p (lhs_type, rhs1_type))
3852 error ("type mismatch in shift expression");
3853 debug_generic_expr (lhs_type);
3854 debug_generic_expr (rhs1_type);
3855 debug_generic_expr (rhs2_type);
3862 case VEC_LSHIFT_EXPR:
3863 case VEC_RSHIFT_EXPR:
3865 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3866 || !(INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))
3867 || FIXED_POINT_TYPE_P (TREE_TYPE (rhs1_type))
3868 || SCALAR_FLOAT_TYPE_P (TREE_TYPE (rhs1_type)))
3869 || (!INTEGRAL_TYPE_P (rhs2_type)
3870 && (TREE_CODE (rhs2_type) != VECTOR_TYPE
3871 || !INTEGRAL_TYPE_P (TREE_TYPE (rhs2_type))))
3872 || !useless_type_conversion_p (lhs_type, rhs1_type))
3874 error ("type mismatch in vector shift expression");
3875 debug_generic_expr (lhs_type);
3876 debug_generic_expr (rhs1_type);
3877 debug_generic_expr (rhs2_type);
3880 /* For shifting a vector of floating point components we
3881 only allow shifting by a constant multiple of the element size. */
3882 if (SCALAR_FLOAT_TYPE_P (TREE_TYPE (rhs1_type))
3883 && (TREE_CODE (rhs2) != INTEGER_CST
3884 || !div_if_zero_remainder (EXACT_DIV_EXPR, rhs2,
3885 TYPE_SIZE (TREE_TYPE (rhs1_type)))))
3887 error ("non-element sized vector shift of floating point vector");
3896 /* We use regular PLUS_EXPR for vectors.
3897 ??? This just makes the checker happy and may not be what is
3899 if (TREE_CODE (lhs_type) == VECTOR_TYPE
3900 && POINTER_TYPE_P (TREE_TYPE (lhs_type)))
3902 if (TREE_CODE (rhs1_type) != VECTOR_TYPE
3903 || TREE_CODE (rhs2_type) != VECTOR_TYPE)
3905 error ("invalid non-vector operands to vector valued plus");
3908 lhs_type = TREE_TYPE (lhs_type);
3909 rhs1_type = TREE_TYPE (rhs1_type);
3910 rhs2_type = TREE_TYPE (rhs2_type);
3911 /* PLUS_EXPR is commutative, so we might end up canonicalizing
3912 the pointer to 2nd place. */
3913 if (POINTER_TYPE_P (rhs2_type))
3915 tree tem = rhs1_type;
3916 rhs1_type = rhs2_type;
3919 goto do_pointer_plus_expr_check;
3925 if (POINTER_TYPE_P (lhs_type)
3926 || POINTER_TYPE_P (rhs1_type)
3927 || POINTER_TYPE_P (rhs2_type))
3929 error ("invalid (pointer) operands to plus/minus");
3933 /* Continue with generic binary expression handling. */
3937 case POINTER_PLUS_EXPR:
3939 do_pointer_plus_expr_check:
3940 if (!POINTER_TYPE_P (rhs1_type)
3941 || !useless_type_conversion_p (lhs_type, rhs1_type)
3942 || !useless_type_conversion_p (sizetype, rhs2_type))
3944 error ("type mismatch in pointer plus expression");
3945 debug_generic_stmt (lhs_type);
3946 debug_generic_stmt (rhs1_type);
3947 debug_generic_stmt (rhs2_type);
3954 case TRUTH_ANDIF_EXPR:
3955 case TRUTH_ORIF_EXPR:
3958 case TRUTH_AND_EXPR:
3960 case TRUTH_XOR_EXPR:
3962 /* We allow any kind of integral typed argument and result. */
3963 if (!INTEGRAL_TYPE_P (rhs1_type)
3964 || !INTEGRAL_TYPE_P (rhs2_type)
3965 || !INTEGRAL_TYPE_P (lhs_type))
3967 error ("type mismatch in binary truth expression");
3968 debug_generic_expr (lhs_type);
3969 debug_generic_expr (rhs1_type);
3970 debug_generic_expr (rhs2_type);
3983 case UNORDERED_EXPR:
3991 /* Comparisons are also binary, but the result type is not
3992 connected to the operand types. */
3993 return verify_gimple_comparison (lhs_type, rhs1, rhs2);
3995 case WIDEN_SUM_EXPR:
3996 case WIDEN_MULT_EXPR:
3997 case VEC_WIDEN_MULT_HI_EXPR:
3998 case VEC_WIDEN_MULT_LO_EXPR:
3999 case VEC_PACK_TRUNC_EXPR:
4000 case VEC_PACK_SAT_EXPR:
4001 case VEC_PACK_FIX_TRUNC_EXPR:
4002 case VEC_EXTRACT_EVEN_EXPR:
4003 case VEC_EXTRACT_ODD_EXPR:
4004 case VEC_INTERLEAVE_HIGH_EXPR:
4005 case VEC_INTERLEAVE_LOW_EXPR:
4010 case TRUNC_DIV_EXPR:
4012 case FLOOR_DIV_EXPR:
4013 case ROUND_DIV_EXPR:
4014 case TRUNC_MOD_EXPR:
4016 case FLOOR_MOD_EXPR:
4017 case ROUND_MOD_EXPR:
4019 case EXACT_DIV_EXPR:
4025 /* Continue with generic binary expression handling. */
4032 if (!useless_type_conversion_p (lhs_type, rhs1_type)
4033 || !useless_type_conversion_p (lhs_type, rhs2_type))
4035 error ("type mismatch in binary expression");
4036 debug_generic_stmt (lhs_type);
4037 debug_generic_stmt (rhs1_type);
4038 debug_generic_stmt (rhs2_type);
4045 /* Verify a gimple assignment statement STMT with a single rhs.
4046 Returns true if anything is wrong. */
4049 verify_gimple_assign_single (gimple stmt)
4051 enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
4052 tree lhs = gimple_assign_lhs (stmt);
4053 tree lhs_type = TREE_TYPE (lhs);
4054 tree rhs1 = gimple_assign_rhs1 (stmt);
4055 tree rhs1_type = TREE_TYPE (rhs1);
4058 if (!useless_type_conversion_p (lhs_type, rhs1_type))
4060 error ("non-trivial conversion at assignment");
4061 debug_generic_expr (lhs_type);
4062 debug_generic_expr (rhs1_type);
4066 if (handled_component_p (lhs))
4067 res |= verify_types_in_gimple_reference (lhs, true);
4069 /* Special codes we cannot handle via their class. */
4074 tree op = TREE_OPERAND (rhs1, 0);
4075 if (!is_gimple_addressable (op))
4077 error ("invalid operand in unary expression");
4081 if (!types_compatible_p (TREE_TYPE (op), TREE_TYPE (TREE_TYPE (rhs1)))
4082 && !one_pointer_to_useless_type_conversion_p (TREE_TYPE (rhs1),
4085 error ("type mismatch in address expression");
4086 debug_generic_stmt (TREE_TYPE (rhs1));
4087 debug_generic_stmt (TREE_TYPE (op));
4091 return verify_types_in_gimple_reference (op, true);
4098 case ALIGN_INDIRECT_REF:
4099 case MISALIGNED_INDIRECT_REF:
4101 case ARRAY_RANGE_REF:
4102 case VIEW_CONVERT_EXPR:
4105 case TARGET_MEM_REF:
4106 if (!is_gimple_reg (lhs)
4107 && is_gimple_reg_type (TREE_TYPE (lhs)))
4109 error ("invalid rhs for gimple memory store");
4110 debug_generic_stmt (lhs);
4111 debug_generic_stmt (rhs1);
4114 return res || verify_types_in_gimple_reference (rhs1, false);
4126 /* tcc_declaration */
4131 if (!is_gimple_reg (lhs)
4132 && !is_gimple_reg (rhs1)
4133 && is_gimple_reg_type (TREE_TYPE (lhs)))
4135 error ("invalid rhs for gimple memory store");
4136 debug_generic_stmt (lhs);
4137 debug_generic_stmt (rhs1);
4146 case WITH_SIZE_EXPR:
4147 case POLYNOMIAL_CHREC:
4150 case REALIGN_LOAD_EXPR:
4160 /* Verify the contents of a GIMPLE_ASSIGN STMT. Returns true when there
4161 is a problem, otherwise false. */
4164 verify_gimple_assign (gimple stmt)
4166 switch (gimple_assign_rhs_class (stmt))
4168 case GIMPLE_SINGLE_RHS:
4169 return verify_gimple_assign_single (stmt);
4171 case GIMPLE_UNARY_RHS:
4172 return verify_gimple_assign_unary (stmt);
4174 case GIMPLE_BINARY_RHS:
4175 return verify_gimple_assign_binary (stmt);
4182 /* Verify the contents of a GIMPLE_RETURN STMT. Returns true when there
4183 is a problem, otherwise false. */
4186 verify_gimple_return (gimple stmt)
4188 tree op = gimple_return_retval (stmt);
4189 tree restype = TREE_TYPE (TREE_TYPE (cfun->decl));
4191 /* We cannot test for present return values as we do not fix up missing
4192 return values from the original source. */
4196 if (!is_gimple_val (op)
4197 && TREE_CODE (op) != RESULT_DECL)
4199 error ("invalid operand in return statement");
4200 debug_generic_stmt (op);
4204 if (!useless_type_conversion_p (restype, TREE_TYPE (op))
4205 /* ??? With C++ we can have the situation that the result
4206 decl is a reference type while the return type is an aggregate. */
4207 && !(TREE_CODE (op) == RESULT_DECL
4208 && TREE_CODE (TREE_TYPE (op)) == REFERENCE_TYPE
4209 && useless_type_conversion_p (restype, TREE_TYPE (TREE_TYPE (op)))))
4211 error ("invalid conversion in return statement");
4212 debug_generic_stmt (restype);
4213 debug_generic_stmt (TREE_TYPE (op));
4221 /* Verify the contents of a GIMPLE_GOTO STMT. Returns true when there
4222 is a problem, otherwise false. */
4225 verify_gimple_goto (gimple stmt)
4227 tree dest = gimple_goto_dest (stmt);
4229 /* ??? We have two canonical forms of direct goto destinations, a
4230 bare LABEL_DECL and an ADDR_EXPR of a LABEL_DECL. */
4231 if (TREE_CODE (dest) != LABEL_DECL
4232 && (!is_gimple_val (dest)
4233 || !POINTER_TYPE_P (TREE_TYPE (dest))))
4235 error ("goto destination is neither a label nor a pointer");
4242 /* Verify the contents of a GIMPLE_SWITCH STMT. Returns true when there
4243 is a problem, otherwise false. */
4246 verify_gimple_switch (gimple stmt)
4248 if (!is_gimple_val (gimple_switch_index (stmt)))
4250 error ("invalid operand to switch statement");
4251 debug_generic_stmt (gimple_switch_index (stmt));
4259 /* Verify the contents of a GIMPLE_PHI. Returns true if there is a problem,
4260 and false otherwise. */
4263 verify_gimple_phi (gimple stmt)
4265 tree type = TREE_TYPE (gimple_phi_result (stmt));
4268 if (TREE_CODE (gimple_phi_result (stmt)) != SSA_NAME)
4270 error ("Invalid PHI result");
4274 for (i = 0; i < gimple_phi_num_args (stmt); i++)
4276 tree arg = gimple_phi_arg_def (stmt, i);
4277 if ((is_gimple_reg (gimple_phi_result (stmt))
4278 && !is_gimple_val (arg))
4279 || (!is_gimple_reg (gimple_phi_result (stmt))
4280 && !is_gimple_addressable (arg)))
4282 error ("Invalid PHI argument");
4283 debug_generic_stmt (arg);
4286 if (!useless_type_conversion_p (type, TREE_TYPE (arg)))
4288 error ("Incompatible types in PHI argument %u", i);
4289 debug_generic_stmt (type);
4290 debug_generic_stmt (TREE_TYPE (arg));
4299 /* Verify a gimple debug statement STMT.
4300 Returns true if anything is wrong. */
4303 verify_gimple_debug (gimple stmt ATTRIBUTE_UNUSED)
4305 /* There isn't much that could be wrong in a gimple debug stmt. A
4306 gimple debug bind stmt, for example, maps a tree, that's usually
4307 a VAR_DECL or a PARM_DECL, but that could also be some scalarized
4308 component or member of an aggregate type, to another tree, that
4309 can be an arbitrary expression. These stmts expand into debug
4310 insns, and are converted to debug notes by var-tracking.c. */
4315 /* Verify the GIMPLE statement STMT. Returns true if there is an
4316 error, otherwise false. */
4319 verify_types_in_gimple_stmt (gimple stmt)
4321 switch (gimple_code (stmt))
4324 return verify_gimple_assign (stmt);
4327 return TREE_CODE (gimple_label_label (stmt)) != LABEL_DECL;
4330 return verify_gimple_call (stmt);
4333 return verify_gimple_comparison (boolean_type_node,
4334 gimple_cond_lhs (stmt),
4335 gimple_cond_rhs (stmt));
4338 return verify_gimple_goto (stmt);
4341 return verify_gimple_switch (stmt);
4344 return verify_gimple_return (stmt);
4350 return verify_gimple_phi (stmt);
4352 /* Tuples that do not have tree operands. */
4354 case GIMPLE_PREDICT:
4356 case GIMPLE_EH_DISPATCH:
4360 /* OpenMP directives are validated by the FE and never operated
4361 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4362 non-gimple expressions when the main index variable has had
4363 its address taken. This does not affect the loop itself
4364 because the header of an GIMPLE_OMP_FOR is merely used to determine
4365 how to setup the parallel iteration. */
4369 return verify_gimple_debug (stmt);
4376 /* Verify the GIMPLE statements inside the sequence STMTS. */
4379 verify_types_in_gimple_seq_2 (gimple_seq stmts)
4381 gimple_stmt_iterator ittr;
4384 for (ittr = gsi_start (stmts); !gsi_end_p (ittr); gsi_next (&ittr))
4386 gimple stmt = gsi_stmt (ittr);
4388 switch (gimple_code (stmt))
4391 err |= verify_types_in_gimple_seq_2 (gimple_bind_body (stmt));
4395 err |= verify_types_in_gimple_seq_2 (gimple_try_eval (stmt));
4396 err |= verify_types_in_gimple_seq_2 (gimple_try_cleanup (stmt));
4399 case GIMPLE_EH_FILTER:
4400 err |= verify_types_in_gimple_seq_2 (gimple_eh_filter_failure (stmt));
4404 err |= verify_types_in_gimple_seq_2 (gimple_catch_handler (stmt));
4409 bool err2 = verify_types_in_gimple_stmt (stmt);
4411 debug_gimple_stmt (stmt);
4421 /* Verify the GIMPLE statements inside the statement list STMTS. */
4424 verify_types_in_gimple_seq (gimple_seq stmts)
4426 if (verify_types_in_gimple_seq_2 (stmts))
4427 internal_error ("verify_gimple failed");
4431 /* Verify STMT, return true if STMT is not in GIMPLE form.
4432 TODO: Implement type checking. */
4435 verify_stmt (gimple_stmt_iterator *gsi)
4438 struct walk_stmt_info wi;
4439 bool last_in_block = gsi_one_before_end_p (*gsi);
4440 gimple stmt = gsi_stmt (*gsi);
4443 if (is_gimple_omp (stmt))
4445 /* OpenMP directives are validated by the FE and never operated
4446 on by the optimizers. Furthermore, GIMPLE_OMP_FOR may contain
4447 non-gimple expressions when the main index variable has had
4448 its address taken. This does not affect the loop itself
4449 because the header of an GIMPLE_OMP_FOR is merely used to determine
4450 how to setup the parallel iteration. */
4454 /* FIXME. The C frontend passes unpromoted arguments in case it
4455 didn't see a function declaration before the call. */
4456 if (is_gimple_call (stmt))
4460 if (!is_gimple_call_addr (gimple_call_fn (stmt)))
4462 error ("invalid function in call statement");
4466 decl = gimple_call_fndecl (stmt);
4468 && TREE_CODE (decl) == FUNCTION_DECL
4469 && DECL_LOOPING_CONST_OR_PURE_P (decl)
4470 && (!DECL_PURE_P (decl))
4471 && (!TREE_READONLY (decl)))
4473 error ("invalid pure const state for function");
4478 if (is_gimple_debug (stmt))
4481 memset (&wi, 0, sizeof (wi));
4482 addr = walk_gimple_op (gsi_stmt (*gsi), verify_expr, &wi);
4485 debug_generic_expr (addr);
4486 inform (gimple_location (gsi_stmt (*gsi)), "in statement");
4487 debug_gimple_stmt (stmt);
4491 /* If the statement is marked as part of an EH region, then it is
4492 expected that the statement could throw. Verify that when we
4493 have optimizations that simplify statements such that we prove
4494 that they cannot throw, that we update other data structures
4496 lp_nr = lookup_stmt_eh_lp (stmt);
4499 if (!stmt_could_throw_p (stmt))
4501 /* During IPA passes, ipa-pure-const sets nothrow flags on calls
4502 and they are updated on statements only after fixup_cfg
4503 is executed at beggining of expansion stage. */
4504 if (cgraph_state != CGRAPH_STATE_IPA_SSA)
4506 error ("statement marked for throw, but doesn%'t");
4510 else if (lp_nr > 0 && !last_in_block && stmt_can_throw_internal (stmt))
4512 error ("statement marked for throw in middle of block");
4520 debug_gimple_stmt (stmt);
4525 /* Return true when the T can be shared. */
4528 tree_node_can_be_shared (tree t)
4530 if (IS_TYPE_OR_DECL_P (t)
4531 || is_gimple_min_invariant (t)
4532 || TREE_CODE (t) == SSA_NAME
4533 || t == error_mark_node
4534 || TREE_CODE (t) == IDENTIFIER_NODE)
4537 if (TREE_CODE (t) == CASE_LABEL_EXPR)
4540 while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4541 && is_gimple_min_invariant (TREE_OPERAND (t, 1)))
4542 || TREE_CODE (t) == COMPONENT_REF
4543 || TREE_CODE (t) == REALPART_EXPR
4544 || TREE_CODE (t) == IMAGPART_EXPR)
4545 t = TREE_OPERAND (t, 0);
4554 /* Called via walk_gimple_stmt. Verify tree sharing. */
4557 verify_node_sharing (tree *tp, int *walk_subtrees, void *data)
4559 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
4560 struct pointer_set_t *visited = (struct pointer_set_t *) wi->info;
4562 if (tree_node_can_be_shared (*tp))
4564 *walk_subtrees = false;
4568 if (pointer_set_insert (visited, *tp))
4575 static bool eh_error_found;
4577 verify_eh_throw_stmt_node (void **slot, void *data)
4579 struct throw_stmt_node *node = (struct throw_stmt_node *)*slot;
4580 struct pointer_set_t *visited = (struct pointer_set_t *) data;
4582 if (!pointer_set_contains (visited, node->stmt))
4584 error ("Dead STMT in EH table");
4585 debug_gimple_stmt (node->stmt);
4586 eh_error_found = true;
4592 /* Verify the GIMPLE statements in every basic block. */
4598 gimple_stmt_iterator gsi;
4600 struct pointer_set_t *visited, *visited_stmts;
4602 struct walk_stmt_info wi;
4604 timevar_push (TV_TREE_STMT_VERIFY);
4605 visited = pointer_set_create ();
4606 visited_stmts = pointer_set_create ();
4608 memset (&wi, 0, sizeof (wi));
4609 wi.info = (void *) visited;
4616 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4618 phi = gsi_stmt (gsi);
4619 pointer_set_insert (visited_stmts, phi);
4620 if (gimple_bb (phi) != bb)
4622 error ("gimple_bb (phi) is set to a wrong basic block");
4626 for (i = 0; i < gimple_phi_num_args (phi); i++)
4628 tree t = gimple_phi_arg_def (phi, i);
4633 error ("missing PHI def");
4634 debug_gimple_stmt (phi);
4638 /* Addressable variables do have SSA_NAMEs but they
4639 are not considered gimple values. */
4640 else if (TREE_CODE (t) != SSA_NAME
4641 && TREE_CODE (t) != FUNCTION_DECL
4642 && !is_gimple_min_invariant (t))
4644 error ("PHI argument is not a GIMPLE value");
4645 debug_gimple_stmt (phi);
4646 debug_generic_expr (t);
4650 addr = walk_tree (&t, verify_node_sharing, visited, NULL);
4653 error ("incorrect sharing of tree nodes");
4654 debug_gimple_stmt (phi);
4655 debug_generic_expr (addr);
4660 #ifdef ENABLE_TYPES_CHECKING
4661 if (verify_gimple_phi (phi))
4663 debug_gimple_stmt (phi);
4669 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); )
4671 gimple stmt = gsi_stmt (gsi);
4673 if (gimple_code (stmt) == GIMPLE_WITH_CLEANUP_EXPR
4674 || gimple_code (stmt) == GIMPLE_BIND)
4676 error ("invalid GIMPLE statement");
4677 debug_gimple_stmt (stmt);
4681 pointer_set_insert (visited_stmts, stmt);
4683 if (gimple_bb (stmt) != bb)
4685 error ("gimple_bb (stmt) is set to a wrong basic block");
4686 debug_gimple_stmt (stmt);
4690 if (gimple_code (stmt) == GIMPLE_LABEL)
4692 tree decl = gimple_label_label (stmt);
4693 int uid = LABEL_DECL_UID (decl);
4696 || VEC_index (basic_block, label_to_block_map, uid) != bb)
4698 error ("incorrect entry in label_to_block_map");
4702 uid = EH_LANDING_PAD_NR (decl);
4705 eh_landing_pad lp = get_eh_landing_pad_from_number (uid);
4706 if (decl != lp->post_landing_pad)
4708 error ("incorrect setting of landing pad number");
4714 err |= verify_stmt (&gsi);
4716 #ifdef ENABLE_TYPES_CHECKING
4717 if (verify_types_in_gimple_stmt (gsi_stmt (gsi)))
4719 debug_gimple_stmt (stmt);
4723 addr = walk_gimple_op (gsi_stmt (gsi), verify_node_sharing, &wi);
4726 error ("incorrect sharing of tree nodes");
4727 debug_gimple_stmt (stmt);
4728 debug_generic_expr (addr);
4735 eh_error_found = false;
4736 if (get_eh_throw_stmt_table (cfun))
4737 htab_traverse (get_eh_throw_stmt_table (cfun),
4738 verify_eh_throw_stmt_node,
4741 if (err | eh_error_found)
4742 internal_error ("verify_stmts failed");
4744 pointer_set_destroy (visited);
4745 pointer_set_destroy (visited_stmts);
4746 verify_histograms ();
4747 timevar_pop (TV_TREE_STMT_VERIFY);
4751 /* Verifies that the flow information is OK. */
4754 gimple_verify_flow_info (void)
4758 gimple_stmt_iterator gsi;
4763 if (ENTRY_BLOCK_PTR->il.gimple)
4765 error ("ENTRY_BLOCK has IL associated with it");
4769 if (EXIT_BLOCK_PTR->il.gimple)
4771 error ("EXIT_BLOCK has IL associated with it");
4775 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
4776 if (e->flags & EDGE_FALLTHRU)
4778 error ("fallthru to exit from bb %d", e->src->index);
4784 bool found_ctrl_stmt = false;
4788 /* Skip labels on the start of basic block. */
4789 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4792 gimple prev_stmt = stmt;
4794 stmt = gsi_stmt (gsi);
4796 if (gimple_code (stmt) != GIMPLE_LABEL)
4799 label = gimple_label_label (stmt);
4800 if (prev_stmt && DECL_NONLOCAL (label))
4802 error ("nonlocal label ");
4803 print_generic_expr (stderr, label, 0);
4804 fprintf (stderr, " is not first in a sequence of labels in bb %d",
4809 if (label_to_block (label) != bb)
4812 print_generic_expr (stderr, label, 0);
4813 fprintf (stderr, " to block does not match in bb %d",
4818 if (decl_function_context (label) != current_function_decl)
4821 print_generic_expr (stderr, label, 0);
4822 fprintf (stderr, " has incorrect context in bb %d",
4828 /* Verify that body of basic block BB is free of control flow. */
4829 for (; !gsi_end_p (gsi); gsi_next (&gsi))
4831 gimple stmt = gsi_stmt (gsi);
4833 if (found_ctrl_stmt)
4835 error ("control flow in the middle of basic block %d",
4840 if (stmt_ends_bb_p (stmt))
4841 found_ctrl_stmt = true;
4843 if (gimple_code (stmt) == GIMPLE_LABEL)
4846 print_generic_expr (stderr, gimple_label_label (stmt), 0);
4847 fprintf (stderr, " in the middle of basic block %d", bb->index);
4852 gsi = gsi_last_bb (bb);
4853 if (gsi_end_p (gsi))
4856 stmt = gsi_stmt (gsi);
4858 if (gimple_code (stmt) == GIMPLE_LABEL)
4861 err |= verify_eh_edges (stmt);
4863 if (is_ctrl_stmt (stmt))
4865 FOR_EACH_EDGE (e, ei, bb->succs)
4866 if (e->flags & EDGE_FALLTHRU)
4868 error ("fallthru edge after a control statement in bb %d",
4874 if (gimple_code (stmt) != GIMPLE_COND)
4876 /* Verify that there are no edges with EDGE_TRUE/FALSE_FLAG set
4877 after anything else but if statement. */
4878 FOR_EACH_EDGE (e, ei, bb->succs)
4879 if (e->flags & (EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))
4881 error ("true/false edge after a non-GIMPLE_COND in bb %d",
4887 switch (gimple_code (stmt))
4894 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
4898 || !(true_edge->flags & EDGE_TRUE_VALUE)
4899 || !(false_edge->flags & EDGE_FALSE_VALUE)
4900 || (true_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4901 || (false_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
4902 || EDGE_COUNT (bb->succs) >= 3)
4904 error ("wrong outgoing edge flags at end of bb %d",
4912 if (simple_goto_p (stmt))
4914 error ("explicit goto at end of bb %d", bb->index);
4919 /* FIXME. We should double check that the labels in the
4920 destination blocks have their address taken. */
4921 FOR_EACH_EDGE (e, ei, bb->succs)
4922 if ((e->flags & (EDGE_FALLTHRU | EDGE_TRUE_VALUE
4923 | EDGE_FALSE_VALUE))
4924 || !(e->flags & EDGE_ABNORMAL))
4926 error ("wrong outgoing edge flags at end of bb %d",
4934 if (!single_succ_p (bb)
4935 || (single_succ_edge (bb)->flags
4936 & (EDGE_FALLTHRU | EDGE_ABNORMAL
4937 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
4939 error ("wrong outgoing edge flags at end of bb %d", bb->index);
4942 if (single_succ (bb) != EXIT_BLOCK_PTR)
4944 error ("return edge does not point to exit in bb %d",
4956 n = gimple_switch_num_labels (stmt);
4958 /* Mark all the destination basic blocks. */
4959 for (i = 0; i < n; ++i)
4961 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
4962 basic_block label_bb = label_to_block (lab);
4963 gcc_assert (!label_bb->aux || label_bb->aux == (void *)1);
4964 label_bb->aux = (void *)1;
4967 /* Verify that the case labels are sorted. */
4968 prev = gimple_switch_label (stmt, 0);
4969 for (i = 1; i < n; ++i)
4971 tree c = gimple_switch_label (stmt, i);
4974 error ("found default case not at the start of "
4980 && !tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c)))
4982 error ("case labels not sorted: ");
4983 print_generic_expr (stderr, prev, 0);
4984 fprintf (stderr," is greater than ");
4985 print_generic_expr (stderr, c, 0);
4986 fprintf (stderr," but comes before it.\n");
4991 /* VRP will remove the default case if it can prove it will
4992 never be executed. So do not verify there always exists
4993 a default case here. */
4995 FOR_EACH_EDGE (e, ei, bb->succs)
4999 error ("extra outgoing edge %d->%d",
5000 bb->index, e->dest->index);
5004 e->dest->aux = (void *)2;
5005 if ((e->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL
5006 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
5008 error ("wrong outgoing edge flags at end of bb %d",
5014 /* Check that we have all of them. */
5015 for (i = 0; i < n; ++i)
5017 tree lab = CASE_LABEL (gimple_switch_label (stmt, i));
5018 basic_block label_bb = label_to_block (lab);
5020 if (label_bb->aux != (void *)2)
5022 error ("missing edge %i->%i", bb->index, label_bb->index);
5027 FOR_EACH_EDGE (e, ei, bb->succs)
5028 e->dest->aux = (void *)0;
5032 case GIMPLE_EH_DISPATCH:
5033 err |= verify_eh_dispatch_edge (stmt);
5041 if (dom_info_state (CDI_DOMINATORS) >= DOM_NO_FAST_QUERY)
5042 verify_dominators (CDI_DOMINATORS);
5048 /* Updates phi nodes after creating a forwarder block joined
5049 by edge FALLTHRU. */
5052 gimple_make_forwarder_block (edge fallthru)
5056 basic_block dummy, bb;
5058 gimple_stmt_iterator gsi;
5060 dummy = fallthru->src;
5061 bb = fallthru->dest;
5063 if (single_pred_p (bb))
5066 /* If we redirected a branch we must create new PHI nodes at the
5068 for (gsi = gsi_start_phis (dummy); !gsi_end_p (gsi); gsi_next (&gsi))
5070 gimple phi, new_phi;
5072 phi = gsi_stmt (gsi);
5073 var = gimple_phi_result (phi);
5074 new_phi = create_phi_node (var, bb);
5075 SSA_NAME_DEF_STMT (var) = new_phi;
5076 gimple_phi_set_result (phi, make_ssa_name (SSA_NAME_VAR (var), phi));
5077 add_phi_arg (new_phi, gimple_phi_result (phi), fallthru,
5081 /* Add the arguments we have stored on edges. */
5082 FOR_EACH_EDGE (e, ei, bb->preds)
5087 flush_pending_stmts (e);
5092 /* Return a non-special label in the head of basic block BLOCK.
5093 Create one if it doesn't exist. */
5096 gimple_block_label (basic_block bb)
5098 gimple_stmt_iterator i, s = gsi_start_bb (bb);
5103 for (i = s; !gsi_end_p (i); first = false, gsi_next (&i))
5105 stmt = gsi_stmt (i);
5106 if (gimple_code (stmt) != GIMPLE_LABEL)
5108 label = gimple_label_label (stmt);
5109 if (!DECL_NONLOCAL (label))
5112 gsi_move_before (&i, &s);
5117 label = create_artificial_label (UNKNOWN_LOCATION);
5118 stmt = gimple_build_label (label);
5119 gsi_insert_before (&s, stmt, GSI_NEW_STMT);
5124 /* Attempt to perform edge redirection by replacing a possibly complex
5125 jump instruction by a goto or by removing the jump completely.
5126 This can apply only if all edges now point to the same block. The
5127 parameters and return values are equivalent to
5128 redirect_edge_and_branch. */
5131 gimple_try_redirect_by_replacing_jump (edge e, basic_block target)
5133 basic_block src = e->src;
5134 gimple_stmt_iterator i;
5137 /* We can replace or remove a complex jump only when we have exactly
5139 if (EDGE_COUNT (src->succs) != 2
5140 /* Verify that all targets will be TARGET. Specifically, the
5141 edge that is not E must also go to TARGET. */
5142 || EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)
5145 i = gsi_last_bb (src);
5149 stmt = gsi_stmt (i);
5151 if (gimple_code (stmt) == GIMPLE_COND || gimple_code (stmt) == GIMPLE_SWITCH)
5153 gsi_remove (&i, true);
5154 e = ssa_redirect_edge (e, target);
5155 e->flags = EDGE_FALLTHRU;
5163 /* Redirect E to DEST. Return NULL on failure. Otherwise, return the
5164 edge representing the redirected branch. */
5167 gimple_redirect_edge_and_branch (edge e, basic_block dest)
5169 basic_block bb = e->src;
5170 gimple_stmt_iterator gsi;
5174 if (e->flags & EDGE_ABNORMAL)
5177 if (e->dest == dest)
5180 if (e->flags & EDGE_EH)
5181 return redirect_eh_edge (e, dest);
5183 if (e->src != ENTRY_BLOCK_PTR)
5185 ret = gimple_try_redirect_by_replacing_jump (e, dest);
5190 gsi = gsi_last_bb (bb);
5191 stmt = gsi_end_p (gsi) ? NULL : gsi_stmt (gsi);
5193 switch (stmt ? gimple_code (stmt) : GIMPLE_ERROR_MARK)
5196 /* For COND_EXPR, we only need to redirect the edge. */
5200 /* No non-abnormal edges should lead from a non-simple goto, and
5201 simple ones should be represented implicitly. */
5206 tree label = gimple_block_label (dest);
5207 tree cases = get_cases_for_edge (e, stmt);
5209 /* If we have a list of cases associated with E, then use it
5210 as it's a lot faster than walking the entire case vector. */
5213 edge e2 = find_edge (e->src, dest);
5220 CASE_LABEL (cases) = label;
5221 cases = TREE_CHAIN (cases);
5224 /* If there was already an edge in the CFG, then we need
5225 to move all the cases associated with E to E2. */
5228 tree cases2 = get_cases_for_edge (e2, stmt);
5230 TREE_CHAIN (last) = TREE_CHAIN (cases2);
5231 TREE_CHAIN (cases2) = first;
5236 size_t i, n = gimple_switch_num_labels (stmt);
5238 for (i = 0; i < n; i++)
5240 tree elt = gimple_switch_label (stmt, i);
5241 if (label_to_block (CASE_LABEL (elt)) == e->dest)
5242 CASE_LABEL (elt) = label;
5250 int i, n = gimple_asm_nlabels (stmt);
5251 tree label = gimple_block_label (dest);
5253 for (i = 0; i < n; ++i)
5255 tree cons = gimple_asm_label_op (stmt, i);
5256 if (label_to_block (TREE_VALUE (cons)) == e->dest)
5257 TREE_VALUE (cons) = label;
5263 gsi_remove (&gsi, true);
5264 e->flags |= EDGE_FALLTHRU;
5267 case GIMPLE_OMP_RETURN:
5268 case GIMPLE_OMP_CONTINUE:
5269 case GIMPLE_OMP_SECTIONS_SWITCH:
5270 case GIMPLE_OMP_FOR:
5271 /* The edges from OMP constructs can be simply redirected. */
5274 case GIMPLE_EH_DISPATCH:
5275 if (!(e->flags & EDGE_FALLTHRU))
5276 redirect_eh_dispatch_edge (stmt, e, dest);
5280 /* Otherwise it must be a fallthru edge, and we don't need to
5281 do anything besides redirecting it. */
5282 gcc_assert (e->flags & EDGE_FALLTHRU);
5286 /* Update/insert PHI nodes as necessary. */
5288 /* Now update the edges in the CFG. */
5289 e = ssa_redirect_edge (e, dest);
5294 /* Returns true if it is possible to remove edge E by redirecting
5295 it to the destination of the other edge from E->src. */
5298 gimple_can_remove_branch_p (const_edge e)
5300 if (e->flags & (EDGE_ABNORMAL | EDGE_EH))
5306 /* Simple wrapper, as we can always redirect fallthru edges. */
5309 gimple_redirect_edge_and_branch_force (edge e, basic_block dest)
5311 e = gimple_redirect_edge_and_branch (e, dest);
5318 /* Splits basic block BB after statement STMT (but at least after the
5319 labels). If STMT is NULL, BB is split just after the labels. */
5322 gimple_split_block (basic_block bb, void *stmt)
5324 gimple_stmt_iterator gsi;
5325 gimple_stmt_iterator gsi_tgt;
5332 new_bb = create_empty_bb (bb);
5334 /* Redirect the outgoing edges. */
5335 new_bb->succs = bb->succs;
5337 FOR_EACH_EDGE (e, ei, new_bb->succs)
5340 if (stmt && gimple_code ((gimple) stmt) == GIMPLE_LABEL)
5343 /* Move everything from GSI to the new basic block. */
5344 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5346 act = gsi_stmt (gsi);
5347 if (gimple_code (act) == GIMPLE_LABEL)
5360 if (gsi_end_p (gsi))
5363 /* Split the statement list - avoid re-creating new containers as this
5364 brings ugly quadratic memory consumption in the inliner.
5365 (We are still quadratic since we need to update stmt BB pointers,
5367 list = gsi_split_seq_before (&gsi);
5368 set_bb_seq (new_bb, list);
5369 for (gsi_tgt = gsi_start (list);
5370 !gsi_end_p (gsi_tgt); gsi_next (&gsi_tgt))
5371 gimple_set_bb (gsi_stmt (gsi_tgt), new_bb);
5377 /* Moves basic block BB after block AFTER. */
5380 gimple_move_block_after (basic_block bb, basic_block after)
5382 if (bb->prev_bb == after)
5386 link_block (bb, after);
5392 /* Return true if basic_block can be duplicated. */
5395 gimple_can_duplicate_bb_p (const_basic_block bb ATTRIBUTE_UNUSED)
5400 /* Create a duplicate of the basic block BB. NOTE: This does not
5401 preserve SSA form. */
5404 gimple_duplicate_bb (basic_block bb)
5407 gimple_stmt_iterator gsi, gsi_tgt;
5408 gimple_seq phis = phi_nodes (bb);
5409 gimple phi, stmt, copy;
5411 new_bb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb);
5413 /* Copy the PHI nodes. We ignore PHI node arguments here because
5414 the incoming edges have not been setup yet. */
5415 for (gsi = gsi_start (phis); !gsi_end_p (gsi); gsi_next (&gsi))
5417 phi = gsi_stmt (gsi);
5418 copy = create_phi_node (gimple_phi_result (phi), new_bb);
5419 create_new_def_for (gimple_phi_result (copy), copy,
5420 gimple_phi_result_ptr (copy));
5423 gsi_tgt = gsi_start_bb (new_bb);
5424 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5426 def_operand_p def_p;
5427 ssa_op_iter op_iter;
5429 stmt = gsi_stmt (gsi);
5430 if (gimple_code (stmt) == GIMPLE_LABEL)
5433 /* Create a new copy of STMT and duplicate STMT's virtual
5435 copy = gimple_copy (stmt);
5436 gsi_insert_after (&gsi_tgt, copy, GSI_NEW_STMT);
5438 maybe_duplicate_eh_stmt (copy, stmt);
5439 gimple_duplicate_stmt_histograms (cfun, copy, cfun, stmt);
5441 /* Create new names for all the definitions created by COPY and
5442 add replacement mappings for each new name. */
5443 FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS)
5444 create_new_def_for (DEF_FROM_PTR (def_p), copy, def_p);
5450 /* Adds phi node arguments for edge E_COPY after basic block duplication. */
5453 add_phi_args_after_copy_edge (edge e_copy)
5455 basic_block bb, bb_copy = e_copy->src, dest;
5458 gimple phi, phi_copy;
5460 gimple_stmt_iterator psi, psi_copy;
5462 if (gimple_seq_empty_p (phi_nodes (e_copy->dest)))
5465 bb = bb_copy->flags & BB_DUPLICATED ? get_bb_original (bb_copy) : bb_copy;
5467 if (e_copy->dest->flags & BB_DUPLICATED)
5468 dest = get_bb_original (e_copy->dest);
5470 dest = e_copy->dest;
5472 e = find_edge (bb, dest);
5475 /* During loop unrolling the target of the latch edge is copied.
5476 In this case we are not looking for edge to dest, but to
5477 duplicated block whose original was dest. */
5478 FOR_EACH_EDGE (e, ei, bb->succs)
5480 if ((e->dest->flags & BB_DUPLICATED)
5481 && get_bb_original (e->dest) == dest)
5485 gcc_assert (e != NULL);
5488 for (psi = gsi_start_phis (e->dest),
5489 psi_copy = gsi_start_phis (e_copy->dest);
5491 gsi_next (&psi), gsi_next (&psi_copy))
5493 phi = gsi_stmt (psi);
5494 phi_copy = gsi_stmt (psi_copy);
5495 def = PHI_ARG_DEF_FROM_EDGE (phi, e);
5496 add_phi_arg (phi_copy, def, e_copy,
5497 gimple_phi_arg_location_from_edge (phi, e));
5502 /* Basic block BB_COPY was created by code duplication. Add phi node
5503 arguments for edges going out of BB_COPY. The blocks that were
5504 duplicated have BB_DUPLICATED set. */
5507 add_phi_args_after_copy_bb (basic_block bb_copy)
5512 FOR_EACH_EDGE (e_copy, ei, bb_copy->succs)
5514 add_phi_args_after_copy_edge (e_copy);
5518 /* Blocks in REGION_COPY array of length N_REGION were created by
5519 duplication of basic blocks. Add phi node arguments for edges
5520 going from these blocks. If E_COPY is not NULL, also add
5521 phi node arguments for its destination.*/
5524 add_phi_args_after_copy (basic_block *region_copy, unsigned n_region,
5529 for (i = 0; i < n_region; i++)
5530 region_copy[i]->flags |= BB_DUPLICATED;
5532 for (i = 0; i < n_region; i++)
5533 add_phi_args_after_copy_bb (region_copy[i]);
5535 add_phi_args_after_copy_edge (e_copy);
5537 for (i = 0; i < n_region; i++)
5538 region_copy[i]->flags &= ~BB_DUPLICATED;
5541 /* Duplicates a REGION (set of N_REGION basic blocks) with just a single
5542 important exit edge EXIT. By important we mean that no SSA name defined
5543 inside region is live over the other exit edges of the region. All entry
5544 edges to the region must go to ENTRY->dest. The edge ENTRY is redirected
5545 to the duplicate of the region. SSA form, dominance and loop information
5546 is updated. The new basic blocks are stored to REGION_COPY in the same
5547 order as they had in REGION, provided that REGION_COPY is not NULL.
5548 The function returns false if it is unable to copy the region,
5552 gimple_duplicate_sese_region (edge entry, edge exit,
5553 basic_block *region, unsigned n_region,
5554 basic_block *region_copy)
5557 bool free_region_copy = false, copying_header = false;
5558 struct loop *loop = entry->dest->loop_father;
5560 VEC (basic_block, heap) *doms;
5562 int total_freq = 0, entry_freq = 0;
5563 gcov_type total_count = 0, entry_count = 0;
5565 if (!can_copy_bbs_p (region, n_region))
5568 /* Some sanity checking. Note that we do not check for all possible
5569 missuses of the functions. I.e. if you ask to copy something weird,
5570 it will work, but the state of structures probably will not be
5572 for (i = 0; i < n_region; i++)
5574 /* We do not handle subloops, i.e. all the blocks must belong to the
5576 if (region[i]->loop_father != loop)
5579 if (region[i] != entry->dest
5580 && region[i] == loop->header)
5584 set_loop_copy (loop, loop);
5586 /* In case the function is used for loop header copying (which is the primary
5587 use), ensure that EXIT and its copy will be new latch and entry edges. */
5588 if (loop->header == entry->dest)
5590 copying_header = true;
5591 set_loop_copy (loop, loop_outer (loop));
5593 if (!dominated_by_p (CDI_DOMINATORS, loop->latch, exit->src))
5596 for (i = 0; i < n_region; i++)
5597 if (region[i] != exit->src
5598 && dominated_by_p (CDI_DOMINATORS, region[i], exit->src))
5604 region_copy = XNEWVEC (basic_block, n_region);
5605 free_region_copy = true;
5608 gcc_assert (!need_ssa_update_p (cfun));
5610 /* Record blocks outside the region that are dominated by something
5613 initialize_original_copy_tables ();
5615 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5617 if (entry->dest->count)
5619 total_count = entry->dest->count;
5620 entry_count = entry->count;
5621 /* Fix up corner cases, to avoid division by zero or creation of negative
5623 if (entry_count > total_count)
5624 entry_count = total_count;
5628 total_freq = entry->dest->frequency;
5629 entry_freq = EDGE_FREQUENCY (entry);
5630 /* Fix up corner cases, to avoid division by zero or creation of negative
5632 if (total_freq == 0)
5634 else if (entry_freq > total_freq)
5635 entry_freq = total_freq;
5638 copy_bbs (region, n_region, region_copy, &exit, 1, &exit_copy, loop,
5639 split_edge_bb_loc (entry));
5642 scale_bbs_frequencies_gcov_type (region, n_region,
5643 total_count - entry_count,
5645 scale_bbs_frequencies_gcov_type (region_copy, n_region, entry_count,
5650 scale_bbs_frequencies_int (region, n_region, total_freq - entry_freq,
5652 scale_bbs_frequencies_int (region_copy, n_region, entry_freq, total_freq);
5657 loop->header = exit->dest;
5658 loop->latch = exit->src;
5661 /* Redirect the entry and add the phi node arguments. */
5662 redirected = redirect_edge_and_branch (entry, get_bb_copy (entry->dest));
5663 gcc_assert (redirected != NULL);
5664 flush_pending_stmts (entry);
5666 /* Concerning updating of dominators: We must recount dominators
5667 for entry block and its copy. Anything that is outside of the
5668 region, but was dominated by something inside needs recounting as
5670 set_immediate_dominator (CDI_DOMINATORS, entry->dest, entry->src);
5671 VEC_safe_push (basic_block, heap, doms, get_bb_original (entry->dest));
5672 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5673 VEC_free (basic_block, heap, doms);
5675 /* Add the other PHI node arguments. */
5676 add_phi_args_after_copy (region_copy, n_region, NULL);
5678 /* Update the SSA web. */
5679 update_ssa (TODO_update_ssa);
5681 if (free_region_copy)
5684 free_original_copy_tables ();
5688 /* Duplicates REGION consisting of N_REGION blocks. The new blocks
5689 are stored to REGION_COPY in the same order in that they appear
5690 in REGION, if REGION_COPY is not NULL. ENTRY is the entry to
5691 the region, EXIT an exit from it. The condition guarding EXIT
5692 is moved to ENTRY. Returns true if duplication succeeds, false
5718 gimple_duplicate_sese_tail (edge entry ATTRIBUTE_UNUSED, edge exit ATTRIBUTE_UNUSED,
5719 basic_block *region ATTRIBUTE_UNUSED, unsigned n_region ATTRIBUTE_UNUSED,
5720 basic_block *region_copy ATTRIBUTE_UNUSED)
5723 bool free_region_copy = false;
5724 struct loop *loop = exit->dest->loop_father;
5725 struct loop *orig_loop = entry->dest->loop_father;
5726 basic_block switch_bb, entry_bb, nentry_bb;
5727 VEC (basic_block, heap) *doms;
5728 int total_freq = 0, exit_freq = 0;
5729 gcov_type total_count = 0, exit_count = 0;
5730 edge exits[2], nexits[2], e;
5731 gimple_stmt_iterator gsi;
5735 gcc_assert (EDGE_COUNT (exit->src->succs) == 2);
5737 exits[1] = EDGE_SUCC (exit->src, EDGE_SUCC (exit->src, 0) == exit);
5739 if (!can_copy_bbs_p (region, n_region))
5742 /* Some sanity checking. Note that we do not check for all possible
5743 missuses of the functions. I.e. if you ask to copy something weird
5744 (e.g., in the example, if there is a jump from inside to the middle
5745 of some_code, or come_code defines some of the values used in cond)
5746 it will work, but the resulting code will not be correct. */
5747 for (i = 0; i < n_region; i++)
5749 /* We do not handle subloops, i.e. all the blocks must belong to the
5751 if (region[i]->loop_father != orig_loop)
5754 if (region[i] == orig_loop->latch)
5758 initialize_original_copy_tables ();
5759 set_loop_copy (orig_loop, loop);
5763 region_copy = XNEWVEC (basic_block, n_region);
5764 free_region_copy = true;
5767 gcc_assert (!need_ssa_update_p (cfun));
5769 /* Record blocks outside the region that are dominated by something
5771 doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
5773 if (exit->src->count)
5775 total_count = exit->src->count;
5776 exit_count = exit->count;
5777 /* Fix up corner cases, to avoid division by zero or creation of negative
5779 if (exit_count > total_count)
5780 exit_count = total_count;
5784 total_freq = exit->src->frequency;
5785 exit_freq = EDGE_FREQUENCY (exit);
5786 /* Fix up corner cases, to avoid division by zero or creation of negative
5788 if (total_freq == 0)
5790 if (exit_freq > total_freq)
5791 exit_freq = total_freq;
5794 copy_bbs (region, n_region, region_copy, exits, 2, nexits, orig_loop,
5795 split_edge_bb_loc (exit));
5798 scale_bbs_frequencies_gcov_type (region, n_region,
5799 total_count - exit_count,
5801 scale_bbs_frequencies_gcov_type (region_copy, n_region, exit_count,
5806 scale_bbs_frequencies_int (region, n_region, total_freq - exit_freq,
5808 scale_bbs_frequencies_int (region_copy, n_region, exit_freq, total_freq);
5811 /* Create the switch block, and put the exit condition to it. */
5812 entry_bb = entry->dest;
5813 nentry_bb = get_bb_copy (entry_bb);
5814 if (!last_stmt (entry->src)
5815 || !stmt_ends_bb_p (last_stmt (entry->src)))
5816 switch_bb = entry->src;
5818 switch_bb = split_edge (entry);
5819 set_immediate_dominator (CDI_DOMINATORS, nentry_bb, switch_bb);
5821 gsi = gsi_last_bb (switch_bb);
5822 cond_stmt = last_stmt (exit->src);
5823 gcc_assert (gimple_code (cond_stmt) == GIMPLE_COND);
5824 cond_stmt = gimple_copy (cond_stmt);
5825 gimple_cond_set_lhs (cond_stmt, unshare_expr (gimple_cond_lhs (cond_stmt)));
5826 gimple_cond_set_rhs (cond_stmt, unshare_expr (gimple_cond_rhs (cond_stmt)));
5827 gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT);
5829 sorig = single_succ_edge (switch_bb);
5830 sorig->flags = exits[1]->flags;
5831 snew = make_edge (switch_bb, nentry_bb, exits[0]->flags);
5833 /* Register the new edge from SWITCH_BB in loop exit lists. */
5834 rescan_loop_exit (snew, true, false);
5836 /* Add the PHI node arguments. */
5837 add_phi_args_after_copy (region_copy, n_region, snew);
5839 /* Get rid of now superfluous conditions and associated edges (and phi node
5841 e = redirect_edge_and_branch (exits[0], exits[1]->dest);
5842 PENDING_STMT (e) = NULL;
5843 e = redirect_edge_and_branch (nexits[1], nexits[0]->dest);
5844 PENDING_STMT (e) = NULL;
5846 /* Anything that is outside of the region, but was dominated by something
5847 inside needs to update dominance info. */
5848 iterate_fix_dominators (CDI_DOMINATORS, doms, false);
5849 VEC_free (basic_block, heap, doms);
5851 /* Update the SSA web. */
5852 update_ssa (TODO_update_ssa);
5854 if (free_region_copy)
5857 free_original_copy_tables ();
5861 /* Add all the blocks dominated by ENTRY to the array BBS_P. Stop
5862 adding blocks when the dominator traversal reaches EXIT. This
5863 function silently assumes that ENTRY strictly dominates EXIT. */
5866 gather_blocks_in_sese_region (basic_block entry, basic_block exit,
5867 VEC(basic_block,heap) **bbs_p)
5871 for (son = first_dom_son (CDI_DOMINATORS, entry);
5873 son = next_dom_son (CDI_DOMINATORS, son))
5875 VEC_safe_push (basic_block, heap, *bbs_p, son);
5877 gather_blocks_in_sese_region (son, exit, bbs_p);
5881 /* Replaces *TP with a duplicate (belonging to function TO_CONTEXT).
5882 The duplicates are recorded in VARS_MAP. */
5885 replace_by_duplicate_decl (tree *tp, struct pointer_map_t *vars_map,
5888 tree t = *tp, new_t;
5889 struct function *f = DECL_STRUCT_FUNCTION (to_context);
5892 if (DECL_CONTEXT (t) == to_context)
5895 loc = pointer_map_contains (vars_map, t);
5899 loc = pointer_map_insert (vars_map, t);
5903 new_t = copy_var_decl (t, DECL_NAME (t), TREE_TYPE (t));
5904 f->local_decls = tree_cons (NULL_TREE, new_t, f->local_decls);
5908 gcc_assert (TREE_CODE (t) == CONST_DECL);
5909 new_t = copy_node (t);
5911 DECL_CONTEXT (new_t) = to_context;
5916 new_t = (tree) *loc;
5922 /* Creates an ssa name in TO_CONTEXT equivalent to NAME.
5923 VARS_MAP maps old ssa names and var_decls to the new ones. */
5926 replace_ssa_name (tree name, struct pointer_map_t *vars_map,
5930 tree new_name, decl = SSA_NAME_VAR (name);
5932 gcc_assert (is_gimple_reg (name));
5934 loc = pointer_map_contains (vars_map, name);
5938 replace_by_duplicate_decl (&decl, vars_map, to_context);
5940 push_cfun (DECL_STRUCT_FUNCTION (to_context));
5941 if (gimple_in_ssa_p (cfun))
5942 add_referenced_var (decl);
5944 new_name = make_ssa_name (decl, SSA_NAME_DEF_STMT (name));
5945 if (SSA_NAME_IS_DEFAULT_DEF (name))
5946 set_default_def (decl, new_name);
5949 loc = pointer_map_insert (vars_map, name);
5953 new_name = (tree) *loc;
5964 struct pointer_map_t *vars_map;
5965 htab_t new_label_map;
5966 struct pointer_map_t *eh_map;
5970 /* Helper for move_block_to_fn. Set TREE_BLOCK in every expression
5971 contained in *TP if it has been ORIG_BLOCK previously and change the
5972 DECL_CONTEXT of every local variable referenced in *TP. */
5975 move_stmt_op (tree *tp, int *walk_subtrees, void *data)
5977 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
5978 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
5982 /* We should never have TREE_BLOCK set on non-statements. */
5983 gcc_assert (!TREE_BLOCK (t));
5985 else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
5987 if (TREE_CODE (t) == SSA_NAME)
5988 *tp = replace_ssa_name (t, p->vars_map, p->to_context);
5989 else if (TREE_CODE (t) == LABEL_DECL)
5991 if (p->new_label_map)
5993 struct tree_map in, *out;
5995 out = (struct tree_map *)
5996 htab_find_with_hash (p->new_label_map, &in, DECL_UID (t));
6001 DECL_CONTEXT (t) = p->to_context;
6003 else if (p->remap_decls_p)
6005 /* Replace T with its duplicate. T should no longer appear in the
6006 parent function, so this looks wasteful; however, it may appear
6007 in referenced_vars, and more importantly, as virtual operands of
6008 statements, and in alias lists of other variables. It would be
6009 quite difficult to expunge it from all those places. ??? It might
6010 suffice to do this for addressable variables. */
6011 if ((TREE_CODE (t) == VAR_DECL
6012 && !is_global_var (t))
6013 || TREE_CODE (t) == CONST_DECL)
6014 replace_by_duplicate_decl (tp, p->vars_map, p->to_context);
6017 && gimple_in_ssa_p (cfun))
6019 push_cfun (DECL_STRUCT_FUNCTION (p->to_context));
6020 add_referenced_var (*tp);
6026 else if (TYPE_P (t))
6032 /* Helper for move_stmt_r. Given an EH region number for the source
6033 function, map that to the duplicate EH regio number in the dest. */
6036 move_stmt_eh_region_nr (int old_nr, struct move_stmt_d *p)
6038 eh_region old_r, new_r;
6041 old_r = get_eh_region_from_number (old_nr);
6042 slot = pointer_map_contains (p->eh_map, old_r);
6043 new_r = (eh_region) *slot;
6045 return new_r->index;
6048 /* Similar, but operate on INTEGER_CSTs. */
6051 move_stmt_eh_region_tree_nr (tree old_t_nr, struct move_stmt_d *p)
6055 old_nr = tree_low_cst (old_t_nr, 0);
6056 new_nr = move_stmt_eh_region_nr (old_nr, p);
6058 return build_int_cst (NULL, new_nr);
6061 /* Like move_stmt_op, but for gimple statements.
6063 Helper for move_block_to_fn. Set GIMPLE_BLOCK in every expression
6064 contained in the current statement in *GSI_P and change the
6065 DECL_CONTEXT of every local variable referenced in the current
6069 move_stmt_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
6070 struct walk_stmt_info *wi)
6072 struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
6073 gimple stmt = gsi_stmt (*gsi_p);
6074 tree block = gimple_block (stmt);
6076 if (p->orig_block == NULL_TREE
6077 || block == p->orig_block
6078 || block == NULL_TREE)
6079 gimple_set_block (stmt, p->new_block);
6080 #ifdef ENABLE_CHECKING
6081 else if (block != p->new_block)
6083 while (block && block != p->orig_block)
6084 block = BLOCK_SUPERCONTEXT (block);
6089 switch (gimple_code (stmt))
6092 /* Remap the region numbers for __builtin_eh_{pointer,filter}. */
6094 tree r, fndecl = gimple_call_fndecl (stmt);
6095 if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
6096 switch (DECL_FUNCTION_CODE (fndecl))
6098 case BUILT_IN_EH_COPY_VALUES:
6099 r = gimple_call_arg (stmt, 1);
6100 r = move_stmt_eh_region_tree_nr (r, p);
6101 gimple_call_set_arg (stmt, 1, r);
6104 case BUILT_IN_EH_POINTER:
6105 case BUILT_IN_EH_FILTER:
6106 r = gimple_call_arg (stmt, 0);
6107 r = move_stmt_eh_region_tree_nr (r, p);
6108 gimple_call_set_arg (stmt, 0, r);
6119 int r = gimple_resx_region (stmt);
6120 r = move_stmt_eh_region_nr (r, p);
6121 gimple_resx_set_region (stmt, r);
6125 case GIMPLE_EH_DISPATCH:
6127 int r = gimple_eh_dispatch_region (stmt);
6128 r = move_stmt_eh_region_nr (r, p);
6129 gimple_eh_dispatch_set_region (stmt, r);
6133 case GIMPLE_OMP_RETURN:
6134 case GIMPLE_OMP_CONTINUE:
6137 if (is_gimple_omp (stmt))
6139 /* Do not remap variables inside OMP directives. Variables
6140 referenced in clauses and directive header belong to the
6141 parent function and should not be moved into the child
6143 bool save_remap_decls_p = p->remap_decls_p;
6144 p->remap_decls_p = false;
6145 *handled_ops_p = true;
6147 walk_gimple_seq (gimple_omp_body (stmt), move_stmt_r,
6150 p->remap_decls_p = save_remap_decls_p;
6158 /* Marks virtual operands of all statements in basic blocks BBS for
6162 mark_virtual_ops_in_bb (basic_block bb)
6164 gimple_stmt_iterator gsi;
6166 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
6167 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
6169 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
6170 mark_virtual_ops_for_renaming (gsi_stmt (gsi));
6173 /* Move basic block BB from function CFUN to function DEST_FN. The
6174 block is moved out of the original linked list and placed after
6175 block AFTER in the new list. Also, the block is removed from the
6176 original array of blocks and placed in DEST_FN's array of blocks.
6177 If UPDATE_EDGE_COUNT_P is true, the edge counts on both CFGs is
6178 updated to reflect the moved edges.
6180 The local variables are remapped to new instances, VARS_MAP is used
6181 to record the mapping. */
6184 move_block_to_fn (struct function *dest_cfun, basic_block bb,
6185 basic_block after, bool update_edge_count_p,
6186 struct move_stmt_d *d)
6188 struct control_flow_graph *cfg;
6191 gimple_stmt_iterator si;
6192 unsigned old_len, new_len;
6194 /* Remove BB from dominance structures. */
6195 delete_from_dominance_info (CDI_DOMINATORS, bb);
6197 remove_bb_from_loops (bb);
6199 /* Link BB to the new linked list. */
6200 move_block_after (bb, after);
6202 /* Update the edge count in the corresponding flowgraphs. */
6203 if (update_edge_count_p)
6204 FOR_EACH_EDGE (e, ei, bb->succs)
6206 cfun->cfg->x_n_edges--;
6207 dest_cfun->cfg->x_n_edges++;
6210 /* Remove BB from the original basic block array. */
6211 VEC_replace (basic_block, cfun->cfg->x_basic_block_info, bb->index, NULL);
6212 cfun->cfg->x_n_basic_blocks--;
6214 /* Grow DEST_CFUN's basic block array if needed. */
6215 cfg = dest_cfun->cfg;
6216 cfg->x_n_basic_blocks++;
6217 if (bb->index >= cfg->x_last_basic_block)
6218 cfg->x_last_basic_block = bb->index + 1;
6220 old_len = VEC_length (basic_block, cfg->x_basic_block_info);
6221 if ((unsigned) cfg->x_last_basic_block >= old_len)
6223 new_len = cfg->x_last_basic_block + (cfg->x_last_basic_block + 3) / 4;
6224 VEC_safe_grow_cleared (basic_block, gc, cfg->x_basic_block_info,
6228 VEC_replace (basic_block, cfg->x_basic_block_info,
6231 /* Remap the variables in phi nodes. */
6232 for (si = gsi_start_phis (bb); !gsi_end_p (si); )
6234 gimple phi = gsi_stmt (si);
6236 tree op = PHI_RESULT (phi);
6239 if (!is_gimple_reg (op))
6241 /* Remove the phi nodes for virtual operands (alias analysis will be
6242 run for the new function, anyway). */
6243 remove_phi_node (&si, true);
6247 SET_PHI_RESULT (phi,
6248 replace_ssa_name (op, d->vars_map, dest_cfun->decl));
6249 FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
6251 op = USE_FROM_PTR (use);
6252 if (TREE_CODE (op) == SSA_NAME)
6253 SET_USE (use, replace_ssa_name (op, d->vars_map, dest_cfun->decl));
6259 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
6261 gimple stmt = gsi_stmt (si);
6262 struct walk_stmt_info wi;
6264 memset (&wi, 0, sizeof (wi));
6266 walk_gimple_stmt (&si, move_stmt_r, move_stmt_op, &wi);
6268 if (gimple_code (stmt) == GIMPLE_LABEL)
6270 tree label = gimple_label_label (stmt);
6271 int uid = LABEL_DECL_UID (label);
6273 gcc_assert (uid > -1);
6275 old_len = VEC_length (basic_block, cfg->x_label_to_block_map);
6276 if (old_len <= (unsigned) uid)
6278 new_len = 3 * uid / 2 + 1;
6279 VEC_safe_grow_cleared (basic_block, gc,
6280 cfg->x_label_to_block_map, new_len);
6283 VEC_replace (basic_block, cfg->x_label_to_block_map, uid, bb);
6284 VEC_replace (basic_block, cfun->cfg->x_label_to_block_map, uid, NULL);
6286 gcc_assert (DECL_CONTEXT (label) == dest_cfun->decl);
6288 if (uid >= dest_cfun->cfg->last_label_uid)
6289 dest_cfun->cfg->last_label_uid = uid + 1;
6292 maybe_duplicate_eh_stmt_fn (dest_cfun, stmt, cfun, stmt, d->eh_map, 0);
6293 remove_stmt_from_eh_lp_fn (cfun, stmt);
6295 gimple_duplicate_stmt_histograms (dest_cfun, stmt, cfun, stmt);
6296 gimple_remove_stmt_histograms (cfun, stmt);
6298 /* We cannot leave any operands allocated from the operand caches of
6299 the current function. */
6300 free_stmt_operands (stmt);
6301 push_cfun (dest_cfun);
6306 FOR_EACH_EDGE (e, ei, bb->succs)
6309 tree block = e->goto_block;
6310 if (d->orig_block == NULL_TREE
6311 || block == d->orig_block)
6312 e->goto_block = d->new_block;
6313 #ifdef ENABLE_CHECKING
6314 else if (block != d->new_block)
6316 while (block && block != d->orig_block)
6317 block = BLOCK_SUPERCONTEXT (block);
6324 /* Examine the statements in BB (which is in SRC_CFUN); find and return
6325 the outermost EH region. Use REGION as the incoming base EH region. */
6328 find_outermost_region_in_block (struct function *src_cfun,
6329 basic_block bb, eh_region region)
6331 gimple_stmt_iterator si;
6333 for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
6335 gimple stmt = gsi_stmt (si);
6336 eh_region stmt_region;
6339 lp_nr = lookup_stmt_eh_lp_fn (src_cfun, stmt);
6340 stmt_region = get_eh_region_from_lp_number_fn (src_cfun, lp_nr);
6344 region = stmt_region;
6345 else if (stmt_region != region)
6347 region = eh_region_outermost (src_cfun, stmt_region, region);
6348 gcc_assert (region != NULL);
6357 new_label_mapper (tree decl, void *data)
6359 htab_t hash = (htab_t) data;
6363 gcc_assert (TREE_CODE (decl) == LABEL_DECL);
6365 m = XNEW (struct tree_map);
6366 m->hash = DECL_UID (decl);
6367 m->base.from = decl;
6368 m->to = create_artificial_label (UNKNOWN_LOCATION);
6369 LABEL_DECL_UID (m->to) = LABEL_DECL_UID (decl);
6370 if (LABEL_DECL_UID (m->to) >= cfun->cfg->last_label_uid)
6371 cfun->cfg->last_label_uid = LABEL_DECL_UID (m->to) + 1;
6373 slot = htab_find_slot_with_hash (hash, m, m->hash, INSERT);
6374 gcc_assert (*slot == NULL);
6381 /* Change DECL_CONTEXT of all BLOCK_VARS in block, including
6385 replace_block_vars_by_duplicates (tree block, struct pointer_map_t *vars_map,
6390 for (tp = &BLOCK_VARS (block); *tp; tp = &TREE_CHAIN (*tp))
6393 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != CONST_DECL)
6395 replace_by_duplicate_decl (&t, vars_map, to_context);
6398 if (TREE_CODE (*tp) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (*tp))
6400 SET_DECL_VALUE_EXPR (t, DECL_VALUE_EXPR (*tp));
6401 DECL_HAS_VALUE_EXPR_P (t) = 1;
6403 TREE_CHAIN (t) = TREE_CHAIN (*tp);
6408 for (block = BLOCK_SUBBLOCKS (block); block; block = BLOCK_CHAIN (block))
6409 replace_block_vars_by_duplicates (block, vars_map, to_context);
6412 /* Move a single-entry, single-exit region delimited by ENTRY_BB and
6413 EXIT_BB to function DEST_CFUN. The whole region is replaced by a
6414 single basic block in the original CFG and the new basic block is
6415 returned. DEST_CFUN must not have a CFG yet.
6417 Note that the region need not be a pure SESE region. Blocks inside
6418 the region may contain calls to abort/exit. The only restriction
6419 is that ENTRY_BB should be the only entry point and it must
6422 Change TREE_BLOCK of all statements in ORIG_BLOCK to the new
6423 functions outermost BLOCK, move all subblocks of ORIG_BLOCK
6424 to the new function.
6426 All local variables referenced in the region are assumed to be in
6427 the corresponding BLOCK_VARS and unexpanded variable lists
6428 associated with DEST_CFUN. */
6431 move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb,
6432 basic_block exit_bb, tree orig_block)
6434 VEC(basic_block,heap) *bbs, *dom_bbs;
6435 basic_block dom_entry = get_immediate_dominator (CDI_DOMINATORS, entry_bb);
6436 basic_block after, bb, *entry_pred, *exit_succ, abb;
6437 struct function *saved_cfun = cfun;
6438 int *entry_flag, *exit_flag;
6439 unsigned *entry_prob, *exit_prob;
6440 unsigned i, num_entry_edges, num_exit_edges;
6443 htab_t new_label_map;
6444 struct pointer_map_t *vars_map, *eh_map;
6445 struct loop *loop = entry_bb->loop_father;
6446 struct move_stmt_d d;
6448 /* If ENTRY does not strictly dominate EXIT, this cannot be an SESE
6450 gcc_assert (entry_bb != exit_bb
6452 || dominated_by_p (CDI_DOMINATORS, exit_bb, entry_bb)));
6454 /* Collect all the blocks in the region. Manually add ENTRY_BB
6455 because it won't be added by dfs_enumerate_from. */
6457 VEC_safe_push (basic_block, heap, bbs, entry_bb);
6458 gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs);
6460 /* The blocks that used to be dominated by something in BBS will now be
6461 dominated by the new block. */
6462 dom_bbs = get_dominated_by_region (CDI_DOMINATORS,
6463 VEC_address (basic_block, bbs),
6464 VEC_length (basic_block, bbs));
6466 /* Detach ENTRY_BB and EXIT_BB from CFUN->CFG. We need to remember
6467 the predecessor edges to ENTRY_BB and the successor edges to
6468 EXIT_BB so that we can re-attach them to the new basic block that
6469 will replace the region. */
6470 num_entry_edges = EDGE_COUNT (entry_bb->preds);
6471 entry_pred = (basic_block *) xcalloc (num_entry_edges, sizeof (basic_block));
6472 entry_flag = (int *) xcalloc (num_entry_edges, sizeof (int));
6473 entry_prob = XNEWVEC (unsigned, num_entry_edges);
6475 for (ei = ei_start (entry_bb->preds); (e = ei_safe_edge (ei)) != NULL;)
6477 entry_prob[i] = e->probability;
6478 entry_flag[i] = e->flags;
6479 entry_pred[i++] = e->src;
6485 num_exit_edges = EDGE_COUNT (exit_bb->succs);
6486 exit_succ = (basic_block *) xcalloc (num_exit_edges,
6487 sizeof (basic_block));
6488 exit_flag = (int *) xcalloc (num_exit_edges, sizeof (int));
6489 exit_prob = XNEWVEC (unsigned, num_exit_edges);
6491 for (ei = ei_start (exit_bb->succs); (e = ei_safe_edge (ei)) != NULL;)
6493 exit_prob[i] = e->probability;
6494 exit_flag[i] = e->flags;
6495 exit_succ[i++] = e->dest;
6507 /* Switch context to the child function to initialize DEST_FN's CFG. */
6508 gcc_assert (dest_cfun->cfg == NULL);
6509 push_cfun (dest_cfun);
6511 init_empty_tree_cfg ();
6513 /* Initialize EH information for the new function. */
6515 new_label_map = NULL;
6518 eh_region region = NULL;
6520 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6521 region = find_outermost_region_in_block (saved_cfun, bb, region);
6523 init_eh_for_function ();
6526 new_label_map = htab_create (17, tree_map_hash, tree_map_eq, free);
6527 eh_map = duplicate_eh_regions (saved_cfun, region, 0,
6528 new_label_mapper, new_label_map);
6534 /* Move blocks from BBS into DEST_CFUN. */
6535 gcc_assert (VEC_length (basic_block, bbs) >= 2);
6536 after = dest_cfun->cfg->x_entry_block_ptr;
6537 vars_map = pointer_map_create ();
6539 memset (&d, 0, sizeof (d));
6540 d.orig_block = orig_block;
6541 d.new_block = DECL_INITIAL (dest_cfun->decl);
6542 d.from_context = cfun->decl;
6543 d.to_context = dest_cfun->decl;
6544 d.vars_map = vars_map;
6545 d.new_label_map = new_label_map;
6547 d.remap_decls_p = true;
6549 for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
6551 /* No need to update edge counts on the last block. It has
6552 already been updated earlier when we detached the region from
6553 the original CFG. */
6554 move_block_to_fn (dest_cfun, bb, after, bb != exit_bb, &d);
6558 /* Rewire BLOCK_SUBBLOCKS of orig_block. */
6562 gcc_assert (BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6564 BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
6565 = BLOCK_SUBBLOCKS (orig_block);
6566 for (block = BLOCK_SUBBLOCKS (orig_block);
6567 block; block = BLOCK_CHAIN (block))
6568 BLOCK_SUPERCONTEXT (block) = DECL_INITIAL (dest_cfun->decl);
6569 BLOCK_SUBBLOCKS (orig_block) = NULL_TREE;
6572 replace_block_vars_by_duplicates (DECL_INITIAL (dest_cfun->decl),
6573 vars_map, dest_cfun->decl);
6576 htab_delete (new_label_map);
6578 pointer_map_destroy (eh_map);
6579 pointer_map_destroy (vars_map);
6581 /* Rewire the entry and exit blocks. The successor to the entry
6582 block turns into the successor of DEST_FN's ENTRY_BLOCK_PTR in
6583 the child function. Similarly, the predecessor of DEST_FN's
6584 EXIT_BLOCK_PTR turns into the predecessor of EXIT_BLOCK_PTR. We
6585 need to switch CFUN between DEST_CFUN and SAVED_CFUN so that the
6586 various CFG manipulation function get to the right CFG.
6588 FIXME, this is silly. The CFG ought to become a parameter to
6590 push_cfun (dest_cfun);
6591 make_edge (ENTRY_BLOCK_PTR, entry_bb, EDGE_FALLTHRU);
6593 make_edge (exit_bb, EXIT_BLOCK_PTR, 0);
6596 /* Back in the original function, the SESE region has disappeared,
6597 create a new basic block in its place. */
6598 bb = create_empty_bb (entry_pred[0]);
6600 add_bb_to_loop (bb, loop);
6601 for (i = 0; i < num_entry_edges; i++)
6603 e = make_edge (entry_pred[i], bb, entry_flag[i]);
6604 e->probability = entry_prob[i];
6607 for (i = 0; i < num_exit_edges; i++)
6609 e = make_edge (bb, exit_succ[i], exit_flag[i]);
6610 e->probability = exit_prob[i];
6613 set_immediate_dominator (CDI_DOMINATORS, bb, dom_entry);
6614 for (i = 0; VEC_iterate (basic_block, dom_bbs, i, abb); i++)
6615 set_immediate_dominator (CDI_DOMINATORS, abb, bb);
6616 VEC_free (basic_block, heap, dom_bbs);
6627 VEC_free (basic_block, heap, bbs);
6633 /* Dump FUNCTION_DECL FN to file FILE using FLAGS (see TDF_* in tree-pass.h)
6637 dump_function_to_file (tree fn, FILE *file, int flags)
6639 tree arg, vars, var;
6640 struct function *dsf;
6641 bool ignore_topmost_bind = false, any_var = false;
6645 fprintf (file, "%s (", lang_hooks.decl_printable_name (fn, 2));
6647 arg = DECL_ARGUMENTS (fn);
6650 print_generic_expr (file, TREE_TYPE (arg), dump_flags);
6651 fprintf (file, " ");
6652 print_generic_expr (file, arg, dump_flags);
6653 if (flags & TDF_VERBOSE)
6654 print_node (file, "", arg, 4);
6655 if (TREE_CHAIN (arg))
6656 fprintf (file, ", ");
6657 arg = TREE_CHAIN (arg);
6659 fprintf (file, ")\n");
6661 if (flags & TDF_VERBOSE)
6662 print_node (file, "", fn, 2);
6664 dsf = DECL_STRUCT_FUNCTION (fn);
6665 if (dsf && (flags & TDF_EH))
6666 dump_eh_tree (file, dsf);
6668 if (flags & TDF_RAW && !gimple_has_body_p (fn))
6670 dump_node (fn, TDF_SLIM | flags, file);
6674 /* Switch CFUN to point to FN. */
6675 push_cfun (DECL_STRUCT_FUNCTION (fn));
6677 /* When GIMPLE is lowered, the variables are no longer available in
6678 BIND_EXPRs, so display them separately. */
6679 if (cfun && cfun->decl == fn && cfun->local_decls)
6681 ignore_topmost_bind = true;
6683 fprintf (file, "{\n");
6684 for (vars = cfun->local_decls; vars; vars = TREE_CHAIN (vars))
6686 var = TREE_VALUE (vars);
6688 print_generic_decl (file, var, flags);
6689 if (flags & TDF_VERBOSE)
6690 print_node (file, "", var, 4);
6691 fprintf (file, "\n");
6697 if (cfun && cfun->decl == fn && cfun->cfg && basic_block_info)
6699 /* If the CFG has been built, emit a CFG-based dump. */
6700 check_bb_profile (ENTRY_BLOCK_PTR, file);
6701 if (!ignore_topmost_bind)
6702 fprintf (file, "{\n");
6704 if (any_var && n_basic_blocks)
6705 fprintf (file, "\n");
6708 gimple_dump_bb (bb, file, 2, flags);
6710 fprintf (file, "}\n");
6711 check_bb_profile (EXIT_BLOCK_PTR, file);
6713 else if (DECL_SAVED_TREE (fn) == NULL)
6715 /* The function is now in GIMPLE form but the CFG has not been
6716 built yet. Emit the single sequence of GIMPLE statements
6717 that make up its body. */
6718 gimple_seq body = gimple_body (fn);
6720 if (gimple_seq_first_stmt (body)
6721 && gimple_seq_first_stmt (body) == gimple_seq_last_stmt (body)
6722 && gimple_code (gimple_seq_first_stmt (body)) == GIMPLE_BIND)
6723 print_gimple_seq (file, body, 0, flags);
6726 if (!ignore_topmost_bind)
6727 fprintf (file, "{\n");
6730 fprintf (file, "\n");
6732 print_gimple_seq (file, body, 2, flags);
6733 fprintf (file, "}\n");
6740 /* Make a tree based dump. */
6741 chain = DECL_SAVED_TREE (fn);
6743 if (chain && TREE_CODE (chain) == BIND_EXPR)
6745 if (ignore_topmost_bind)
6747 chain = BIND_EXPR_BODY (chain);
6755 if (!ignore_topmost_bind)
6756 fprintf (file, "{\n");
6761 fprintf (file, "\n");
6763 print_generic_stmt_indented (file, chain, flags, indent);
6764 if (ignore_topmost_bind)
6765 fprintf (file, "}\n");
6768 fprintf (file, "\n\n");
6775 /* Dump FUNCTION_DECL FN to stderr using FLAGS (see TDF_* in tree.h) */
6778 debug_function (tree fn, int flags)
6780 dump_function_to_file (fn, stderr, flags);
6784 /* Print on FILE the indexes for the predecessors of basic_block BB. */
6787 print_pred_bbs (FILE *file, basic_block bb)
6792 FOR_EACH_EDGE (e, ei, bb->preds)
6793 fprintf (file, "bb_%d ", e->src->index);
6797 /* Print on FILE the indexes for the successors of basic_block BB. */
6800 print_succ_bbs (FILE *file, basic_block bb)
6805 FOR_EACH_EDGE (e, ei, bb->succs)
6806 fprintf (file, "bb_%d ", e->dest->index);
6809 /* Print to FILE the basic block BB following the VERBOSITY level. */
6812 print_loops_bb (FILE *file, basic_block bb, int indent, int verbosity)
6814 char *s_indent = (char *) alloca ((size_t) indent + 1);
6815 memset ((void *) s_indent, ' ', (size_t) indent);
6816 s_indent[indent] = '\0';
6818 /* Print basic_block's header. */
6821 fprintf (file, "%s bb_%d (preds = {", s_indent, bb->index);
6822 print_pred_bbs (file, bb);
6823 fprintf (file, "}, succs = {");
6824 print_succ_bbs (file, bb);
6825 fprintf (file, "})\n");
6828 /* Print basic_block's body. */
6831 fprintf (file, "%s {\n", s_indent);
6832 gimple_dump_bb (bb, file, indent + 4, TDF_VOPS|TDF_MEMSYMS);
6833 fprintf (file, "%s }\n", s_indent);
6837 static void print_loop_and_siblings (FILE *, struct loop *, int, int);
6839 /* Pretty print LOOP on FILE, indented INDENT spaces. Following
6840 VERBOSITY level this outputs the contents of the loop, or just its
6844 print_loop (FILE *file, struct loop *loop, int indent, int verbosity)
6852 s_indent = (char *) alloca ((size_t) indent + 1);
6853 memset ((void *) s_indent, ' ', (size_t) indent);
6854 s_indent[indent] = '\0';
6856 /* Print loop's header. */
6857 fprintf (file, "%sloop_%d (header = %d, latch = %d", s_indent,
6858 loop->num, loop->header->index, loop->latch->index);
6859 fprintf (file, ", niter = ");
6860 print_generic_expr (file, loop->nb_iterations, 0);
6862 if (loop->any_upper_bound)
6864 fprintf (file, ", upper_bound = ");
6865 dump_double_int (file, loop->nb_iterations_upper_bound, true);
6868 if (loop->any_estimate)
6870 fprintf (file, ", estimate = ");
6871 dump_double_int (file, loop->nb_iterations_estimate, true);
6873 fprintf (file, ")\n");
6875 /* Print loop's body. */
6878 fprintf (file, "%s{\n", s_indent);
6880 if (bb->loop_father == loop)
6881 print_loops_bb (file, bb, indent, verbosity);
6883 print_loop_and_siblings (file, loop->inner, indent + 2, verbosity);
6884 fprintf (file, "%s}\n", s_indent);
6888 /* Print the LOOP and its sibling loops on FILE, indented INDENT
6889 spaces. Following VERBOSITY level this outputs the contents of the
6890 loop, or just its structure. */
6893 print_loop_and_siblings (FILE *file, struct loop *loop, int indent, int verbosity)
6898 print_loop (file, loop, indent, verbosity);
6899 print_loop_and_siblings (file, loop->next, indent, verbosity);
6902 /* Follow a CFG edge from the entry point of the program, and on entry
6903 of a loop, pretty print the loop structure on FILE. */
6906 print_loops (FILE *file, int verbosity)
6910 bb = ENTRY_BLOCK_PTR;
6911 if (bb && bb->loop_father)
6912 print_loop_and_siblings (file, bb->loop_father, 0, verbosity);
6916 /* Debugging loops structure at tree level, at some VERBOSITY level. */
6919 debug_loops (int verbosity)
6921 print_loops (stderr, verbosity);
6924 /* Print on stderr the code of LOOP, at some VERBOSITY level. */
6927 debug_loop (struct loop *loop, int verbosity)
6929 print_loop (stderr, loop, 0, verbosity);
6932 /* Print on stderr the code of loop number NUM, at some VERBOSITY
6936 debug_loop_num (unsigned num, int verbosity)
6938 debug_loop (get_loop (num), verbosity);
6941 /* Return true if BB ends with a call, possibly followed by some
6942 instructions that must stay with the call. Return false,
6946 gimple_block_ends_with_call_p (basic_block bb)
6948 gimple_stmt_iterator gsi = gsi_last_nondebug_bb (bb);
6949 return is_gimple_call (gsi_stmt (gsi));
6953 /* Return true if BB ends with a conditional branch. Return false,
6957 gimple_block_ends_with_condjump_p (const_basic_block bb)
6959 gimple stmt = last_stmt (CONST_CAST_BB (bb));
6960 return (stmt && gimple_code (stmt) == GIMPLE_COND);
6964 /* Return true if we need to add fake edge to exit at statement T.
6965 Helper function for gimple_flow_call_edges_add. */
6968 need_fake_edge_p (gimple t)
6970 tree fndecl = NULL_TREE;
6973 /* NORETURN and LONGJMP calls already have an edge to exit.
6974 CONST and PURE calls do not need one.
6975 We don't currently check for CONST and PURE here, although
6976 it would be a good idea, because those attributes are
6977 figured out from the RTL in mark_constant_function, and
6978 the counter incrementation code from -fprofile-arcs
6979 leads to different results from -fbranch-probabilities. */
6980 if (is_gimple_call (t))
6982 fndecl = gimple_call_fndecl (t);
6983 call_flags = gimple_call_flags (t);
6986 if (is_gimple_call (t)
6988 && DECL_BUILT_IN (fndecl)
6989 && (call_flags & ECF_NOTHROW)
6990 && !(call_flags & ECF_RETURNS_TWICE)
6991 /* fork() doesn't really return twice, but the effect of
6992 wrapping it in __gcov_fork() which calls __gcov_flush()
6993 and clears the counters before forking has the same
6994 effect as returning twice. Force a fake edge. */
6995 && !(DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6996 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_FORK))
6999 if (is_gimple_call (t)
7000 && !(call_flags & ECF_NORETURN))
7003 if (gimple_code (t) == GIMPLE_ASM
7004 && (gimple_asm_volatile_p (t) || gimple_asm_input_p (t)))
7011 /* Add fake edges to the function exit for any non constant and non
7012 noreturn calls, volatile inline assembly in the bitmap of blocks
7013 specified by BLOCKS or to the whole CFG if BLOCKS is zero. Return
7014 the number of blocks that were split.
7016 The goal is to expose cases in which entering a basic block does
7017 not imply that all subsequent instructions must be executed. */
7020 gimple_flow_call_edges_add (sbitmap blocks)
7023 int blocks_split = 0;
7024 int last_bb = last_basic_block;
7025 bool check_last_block = false;
7027 if (n_basic_blocks == NUM_FIXED_BLOCKS)
7031 check_last_block = true;
7033 check_last_block = TEST_BIT (blocks, EXIT_BLOCK_PTR->prev_bb->index);
7035 /* In the last basic block, before epilogue generation, there will be
7036 a fallthru edge to EXIT. Special care is required if the last insn
7037 of the last basic block is a call because make_edge folds duplicate
7038 edges, which would result in the fallthru edge also being marked
7039 fake, which would result in the fallthru edge being removed by
7040 remove_fake_edges, which would result in an invalid CFG.
7042 Moreover, we can't elide the outgoing fake edge, since the block
7043 profiler needs to take this into account in order to solve the minimal
7044 spanning tree in the case that the call doesn't return.
7046 Handle this by adding a dummy instruction in a new last basic block. */
7047 if (check_last_block)
7049 basic_block bb = EXIT_BLOCK_PTR->prev_bb;
7050 gimple_stmt_iterator gsi = gsi_last_bb (bb);
7053 if (!gsi_end_p (gsi))
7056 if (t && need_fake_edge_p (t))
7060 e = find_edge (bb, EXIT_BLOCK_PTR);
7063 gsi_insert_on_edge (e, gimple_build_nop ());
7064 gsi_commit_edge_inserts ();
7069 /* Now add fake edges to the function exit for any non constant
7070 calls since there is no way that we can determine if they will
7072 for (i = 0; i < last_bb; i++)
7074 basic_block bb = BASIC_BLOCK (i);
7075 gimple_stmt_iterator gsi;
7076 gimple stmt, last_stmt;
7081 if (blocks && !TEST_BIT (blocks, i))
7084 gsi = gsi_last_bb (bb);
7085 if (!gsi_end_p (gsi))
7087 last_stmt = gsi_stmt (gsi);
7090 stmt = gsi_stmt (gsi);
7091 if (need_fake_edge_p (stmt))
7095 /* The handling above of the final block before the
7096 epilogue should be enough to verify that there is
7097 no edge to the exit block in CFG already.
7098 Calling make_edge in such case would cause us to
7099 mark that edge as fake and remove it later. */
7100 #ifdef ENABLE_CHECKING
7101 if (stmt == last_stmt)
7103 e = find_edge (bb, EXIT_BLOCK_PTR);
7104 gcc_assert (e == NULL);
7108 /* Note that the following may create a new basic block
7109 and renumber the existing basic blocks. */
7110 if (stmt != last_stmt)
7112 e = split_block (bb, stmt);
7116 make_edge (bb, EXIT_BLOCK_PTR, EDGE_FAKE);
7120 while (!gsi_end_p (gsi));
7125 verify_flow_info ();
7127 return blocks_split;
7130 /* Purge dead abnormal call edges from basic block BB. */
7133 gimple_purge_dead_abnormal_call_edges (basic_block bb)
7135 bool changed = gimple_purge_dead_eh_edges (bb);
7137 if (cfun->has_nonlocal_label)
7139 gimple stmt = last_stmt (bb);
7143 if (!(stmt && stmt_can_make_abnormal_goto (stmt)))
7144 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
7146 if (e->flags & EDGE_ABNORMAL)
7155 /* See gimple_purge_dead_eh_edges below. */
7157 free_dominance_info (CDI_DOMINATORS);
7163 /* Removes edge E and all the blocks dominated by it, and updates dominance
7164 information. The IL in E->src needs to be updated separately.
7165 If dominance info is not available, only the edge E is removed.*/
7168 remove_edge_and_dominated_blocks (edge e)
7170 VEC (basic_block, heap) *bbs_to_remove = NULL;
7171 VEC (basic_block, heap) *bbs_to_fix_dom = NULL;
7175 bool none_removed = false;
7177 basic_block bb, dbb;
7180 if (!dom_info_available_p (CDI_DOMINATORS))
7186 /* No updating is needed for edges to exit. */
7187 if (e->dest == EXIT_BLOCK_PTR)
7189 if (cfgcleanup_altered_bbs)
7190 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
7195 /* First, we find the basic blocks to remove. If E->dest has a predecessor
7196 that is not dominated by E->dest, then this set is empty. Otherwise,
7197 all the basic blocks dominated by E->dest are removed.
7199 Also, to DF_IDOM we store the immediate dominators of the blocks in
7200 the dominance frontier of E (i.e., of the successors of the
7201 removed blocks, if there are any, and of E->dest otherwise). */
7202 FOR_EACH_EDGE (f, ei, e->dest->preds)
7207 if (!dominated_by_p (CDI_DOMINATORS, f->src, e->dest))
7209 none_removed = true;
7214 df = BITMAP_ALLOC (NULL);
7215 df_idom = BITMAP_ALLOC (NULL);
7218 bitmap_set_bit (df_idom,
7219 get_immediate_dominator (CDI_DOMINATORS, e->dest)->index);
7222 bbs_to_remove = get_all_dominated_blocks (CDI_DOMINATORS, e->dest);
7223 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
7225 FOR_EACH_EDGE (f, ei, bb->succs)
7227 if (f->dest != EXIT_BLOCK_PTR)
7228 bitmap_set_bit (df, f->dest->index);
7231 for (i = 0; VEC_iterate (basic_block, bbs_to_remove, i, bb); i++)
7232 bitmap_clear_bit (df, bb->index);
7234 EXECUTE_IF_SET_IN_BITMAP (df, 0, i, bi)
7236 bb = BASIC_BLOCK (i);
7237 bitmap_set_bit (df_idom,
7238 get_immediate_dominator (CDI_DOMINATORS, bb)->index);
7242 if (cfgcleanup_altered_bbs)
7244 /* Record the set of the altered basic blocks. */
7245 bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
7246 bitmap_ior_into (cfgcleanup_altered_bbs, df);
7249 /* Remove E and the cancelled blocks. */
7254 /* Walk backwards so as to get a chance to substitute all
7255 released DEFs into debug stmts. See
7256 eliminate_unnecessary_stmts() in tree-ssa-dce.c for more
7258 for (i = VEC_length (basic_block, bbs_to_remove); i-- > 0; )
7259 delete_basic_block (VEC_index (basic_block, bbs_to_remove, i));
7262 /* Update the dominance information. The immediate dominator may change only
7263 for blocks whose immediate dominator belongs to DF_IDOM:
7265 Suppose that idom(X) = Y before removal of E and idom(X) != Y after the
7266 removal. Let Z the arbitrary block such that idom(Z) = Y and
7267 Z dominates X after the removal. Before removal, there exists a path P
7268 from Y to X that avoids Z. Let F be the last edge on P that is
7269 removed, and let W = F->dest. Before removal, idom(W) = Y (since Y
7270 dominates W, and because of P, Z does not dominate W), and W belongs to
7271 the dominance frontier of E. Therefore, Y belongs to DF_IDOM. */
7272 EXECUTE_IF_SET_IN_BITMAP (df_idom, 0, i, bi)
7274 bb = BASIC_BLOCK (i);
7275 for (dbb = first_dom_son (CDI_DOMINATORS, bb);
7277 dbb = next_dom_son (CDI_DOMINATORS, dbb))
7278 VEC_safe_push (basic_block, heap, bbs_to_fix_dom, dbb);
7281 iterate_fix_dominators (CDI_DOMINATORS, bbs_to_fix_dom, true);
7284 BITMAP_FREE (df_idom);
7285 VEC_free (basic_block, heap, bbs_to_remove);
7286 VEC_free (basic_block, heap, bbs_to_fix_dom);
7289 /* Purge dead EH edges from basic block BB. */
7292 gimple_purge_dead_eh_edges (basic_block bb)
7294 bool changed = false;
7297 gimple stmt = last_stmt (bb);
7299 if (stmt && stmt_can_throw_internal (stmt))
7302 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
7304 if (e->flags & EDGE_EH)
7306 remove_edge_and_dominated_blocks (e);
7317 gimple_purge_all_dead_eh_edges (const_bitmap blocks)
7319 bool changed = false;
7323 EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
7325 basic_block bb = BASIC_BLOCK (i);
7327 /* Earlier gimple_purge_dead_eh_edges could have removed
7328 this basic block already. */
7329 gcc_assert (bb || changed);
7331 changed |= gimple_purge_dead_eh_edges (bb);
7337 /* This function is called whenever a new edge is created or
7341 gimple_execute_on_growing_pred (edge e)
7343 basic_block bb = e->dest;
7346 reserve_phi_args_for_new_edge (bb);
7349 /* This function is called immediately before edge E is removed from
7350 the edge vector E->dest->preds. */
7353 gimple_execute_on_shrinking_pred (edge e)
7355 if (phi_nodes (e->dest))
7356 remove_phi_args (e);
7359 /*---------------------------------------------------------------------------
7360 Helper functions for Loop versioning
7361 ---------------------------------------------------------------------------*/
7363 /* Adjust phi nodes for 'first' basic block. 'second' basic block is a copy
7364 of 'first'. Both of them are dominated by 'new_head' basic block. When
7365 'new_head' was created by 'second's incoming edge it received phi arguments
7366 on the edge by split_edge(). Later, additional edge 'e' was created to
7367 connect 'new_head' and 'first'. Now this routine adds phi args on this
7368 additional edge 'e' that new_head to second edge received as part of edge
7372 gimple_lv_adjust_loop_header_phi (basic_block first, basic_block second,
7373 basic_block new_head, edge e)
7376 gimple_stmt_iterator psi1, psi2;
7378 edge e2 = find_edge (new_head, second);
7380 /* Because NEW_HEAD has been created by splitting SECOND's incoming
7381 edge, we should always have an edge from NEW_HEAD to SECOND. */
7382 gcc_assert (e2 != NULL);
7384 /* Browse all 'second' basic block phi nodes and add phi args to
7385 edge 'e' for 'first' head. PHI args are always in correct order. */
7387 for (psi2 = gsi_start_phis (second),
7388 psi1 = gsi_start_phis (first);
7389 !gsi_end_p (psi2) && !gsi_end_p (psi1);
7390 gsi_next (&psi2), gsi_next (&psi1))
7392 phi1 = gsi_stmt (psi1);
7393 phi2 = gsi_stmt (psi2);
7394 def = PHI_ARG_DEF (phi2, e2->dest_idx);
7395 add_phi_arg (phi1, def, e, gimple_phi_arg_location_from_edge (phi2, e2));
7400 /* Adds a if else statement to COND_BB with condition COND_EXPR.
7401 SECOND_HEAD is the destination of the THEN and FIRST_HEAD is
7402 the destination of the ELSE part. */
7405 gimple_lv_add_condition_to_bb (basic_block first_head ATTRIBUTE_UNUSED,
7406 basic_block second_head ATTRIBUTE_UNUSED,
7407 basic_block cond_bb, void *cond_e)
7409 gimple_stmt_iterator gsi;
7410 gimple new_cond_expr;
7411 tree cond_expr = (tree) cond_e;
7414 /* Build new conditional expr */
7415 new_cond_expr = gimple_build_cond_from_tree (cond_expr,
7416 NULL_TREE, NULL_TREE);
7418 /* Add new cond in cond_bb. */
7419 gsi = gsi_last_bb (cond_bb);
7420 gsi_insert_after (&gsi, new_cond_expr, GSI_NEW_STMT);
7422 /* Adjust edges appropriately to connect new head with first head
7423 as well as second head. */
7424 e0 = single_succ_edge (cond_bb);
7425 e0->flags &= ~EDGE_FALLTHRU;
7426 e0->flags |= EDGE_FALSE_VALUE;
7429 struct cfg_hooks gimple_cfg_hooks = {
7431 gimple_verify_flow_info,
7432 gimple_dump_bb, /* dump_bb */
7433 create_bb, /* create_basic_block */
7434 gimple_redirect_edge_and_branch, /* redirect_edge_and_branch */
7435 gimple_redirect_edge_and_branch_force, /* redirect_edge_and_branch_force */
7436 gimple_can_remove_branch_p, /* can_remove_branch_p */
7437 remove_bb, /* delete_basic_block */
7438 gimple_split_block, /* split_block */
7439 gimple_move_block_after, /* move_block_after */
7440 gimple_can_merge_blocks_p, /* can_merge_blocks_p */
7441 gimple_merge_blocks, /* merge_blocks */
7442 gimple_predict_edge, /* predict_edge */
7443 gimple_predicted_by_p, /* predicted_by_p */
7444 gimple_can_duplicate_bb_p, /* can_duplicate_block_p */
7445 gimple_duplicate_bb, /* duplicate_block */
7446 gimple_split_edge, /* split_edge */
7447 gimple_make_forwarder_block, /* make_forward_block */
7448 NULL, /* tidy_fallthru_edge */
7449 gimple_block_ends_with_call_p,/* block_ends_with_call_p */
7450 gimple_block_ends_with_condjump_p, /* block_ends_with_condjump_p */
7451 gimple_flow_call_edges_add, /* flow_call_edges_add */
7452 gimple_execute_on_growing_pred, /* execute_on_growing_pred */
7453 gimple_execute_on_shrinking_pred, /* execute_on_shrinking_pred */
7454 gimple_duplicate_loop_to_header_edge, /* duplicate loop for trees */
7455 gimple_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
7456 gimple_lv_adjust_loop_header_phi, /* lv_adjust_loop_header_phi*/
7457 extract_true_false_edges_from_block, /* extract_cond_bb_edges */
7458 flush_pending_stmts /* flush_pending_stmts */
7462 /* Split all critical edges. */
7465 split_critical_edges (void)
7471 /* split_edge can redirect edges out of SWITCH_EXPRs, which can get
7472 expensive. So we want to enable recording of edge to CASE_LABEL_EXPR
7473 mappings around the calls to split_edge. */
7474 start_recording_case_labels ();
7477 FOR_EACH_EDGE (e, ei, bb->succs)
7479 if (EDGE_CRITICAL_P (e) && !(e->flags & EDGE_ABNORMAL))
7481 /* PRE inserts statements to edges and expects that
7482 since split_critical_edges was done beforehand, committing edge
7483 insertions will not split more edges. In addition to critical
7484 edges we must split edges that have multiple successors and
7485 end by control flow statements, such as RESX.
7486 Go ahead and split them too. This matches the logic in
7487 gimple_find_edge_insert_loc. */
7488 else if ((!single_pred_p (e->dest)
7489 || !gimple_seq_empty_p (phi_nodes (e->dest))
7490 || e->dest == EXIT_BLOCK_PTR)
7491 && e->src != ENTRY_BLOCK_PTR
7492 && !(e->flags & EDGE_ABNORMAL))
7494 gimple_stmt_iterator gsi;
7496 gsi = gsi_last_bb (e->src);
7497 if (!gsi_end_p (gsi)
7498 && stmt_ends_bb_p (gsi_stmt (gsi))
7499 && gimple_code (gsi_stmt (gsi)) != GIMPLE_RETURN)
7504 end_recording_case_labels ();
7508 struct gimple_opt_pass pass_split_crit_edges =
7512 "crited", /* name */
7514 split_critical_edges, /* execute */
7517 0, /* static_pass_number */
7518 TV_TREE_SPLIT_EDGES, /* tv_id */
7519 PROP_cfg, /* properties required */
7520 PROP_no_crit_edges, /* properties_provided */
7521 0, /* properties_destroyed */
7522 0, /* todo_flags_start */
7523 TODO_dump_func | TODO_verify_flow /* todo_flags_finish */
7528 /* Build a ternary operation and gimplify it. Emit code before GSI.
7529 Return the gimple_val holding the result. */
7532 gimplify_build3 (gimple_stmt_iterator *gsi, enum tree_code code,
7533 tree type, tree a, tree b, tree c)
7536 location_t loc = gimple_location (gsi_stmt (*gsi));
7538 ret = fold_build3_loc (loc, code, type, a, b, c);
7541 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7545 /* Build a binary operation and gimplify it. Emit code before GSI.
7546 Return the gimple_val holding the result. */
7549 gimplify_build2 (gimple_stmt_iterator *gsi, enum tree_code code,
7550 tree type, tree a, tree b)
7554 ret = fold_build2_loc (gimple_location (gsi_stmt (*gsi)), code, type, a, b);
7557 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7561 /* Build a unary operation and gimplify it. Emit code before GSI.
7562 Return the gimple_val holding the result. */
7565 gimplify_build1 (gimple_stmt_iterator *gsi, enum tree_code code, tree type,
7570 ret = fold_build1_loc (gimple_location (gsi_stmt (*gsi)), code, type, a);
7573 return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
7579 /* Emit return warnings. */
7582 execute_warn_function_return (void)
7584 source_location location;
7589 /* If we have a path to EXIT, then we do return. */
7590 if (TREE_THIS_VOLATILE (cfun->decl)
7591 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0)
7593 location = UNKNOWN_LOCATION;
7594 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7596 last = last_stmt (e->src);
7597 if (gimple_code (last) == GIMPLE_RETURN
7598 && (location = gimple_location (last)) != UNKNOWN_LOCATION)
7601 if (location == UNKNOWN_LOCATION)
7602 location = cfun->function_end_locus;
7603 warning_at (location, 0, "%<noreturn%> function does return");
7606 /* If we see "return;" in some basic block, then we do reach the end
7607 without returning a value. */
7608 else if (warn_return_type
7609 && !TREE_NO_WARNING (cfun->decl)
7610 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) > 0
7611 && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (cfun->decl))))
7613 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
7615 gimple last = last_stmt (e->src);
7616 if (gimple_code (last) == GIMPLE_RETURN
7617 && gimple_return_retval (last) == NULL
7618 && !gimple_no_warning_p (last))
7620 location = gimple_location (last);
7621 if (location == UNKNOWN_LOCATION)
7622 location = cfun->function_end_locus;
7623 warning_at (location, OPT_Wreturn_type, "control reaches end of non-void function");
7624 TREE_NO_WARNING (cfun->decl) = 1;
7633 /* Given a basic block B which ends with a conditional and has
7634 precisely two successors, determine which of the edges is taken if
7635 the conditional is true and which is taken if the conditional is
7636 false. Set TRUE_EDGE and FALSE_EDGE appropriately. */
7639 extract_true_false_edges_from_block (basic_block b,
7643 edge e = EDGE_SUCC (b, 0);
7645 if (e->flags & EDGE_TRUE_VALUE)
7648 *false_edge = EDGE_SUCC (b, 1);
7653 *true_edge = EDGE_SUCC (b, 1);
7657 struct gimple_opt_pass pass_warn_function_return =
7663 execute_warn_function_return, /* execute */
7666 0, /* static_pass_number */
7667 TV_NONE, /* tv_id */
7668 PROP_cfg, /* properties_required */
7669 0, /* properties_provided */
7670 0, /* properties_destroyed */
7671 0, /* todo_flags_start */
7672 0 /* todo_flags_finish */
7676 /* Emit noreturn warnings. */
7679 execute_warn_function_noreturn (void)
7681 if (warn_missing_noreturn
7682 && !TREE_THIS_VOLATILE (cfun->decl)
7683 && EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 0
7684 && !lang_hooks.missing_noreturn_ok_p (cfun->decl))
7685 warning_at (DECL_SOURCE_LOCATION (cfun->decl), OPT_Wmissing_noreturn,
7686 "function might be possible candidate "
7687 "for attribute %<noreturn%>");
7691 struct gimple_opt_pass pass_warn_function_noreturn =
7697 execute_warn_function_noreturn, /* execute */
7700 0, /* static_pass_number */
7701 TV_NONE, /* tv_id */
7702 PROP_cfg, /* properties_required */
7703 0, /* properties_provided */
7704 0, /* properties_destroyed */
7705 0, /* todo_flags_start */
7706 0 /* todo_flags_finish */
7711 /* Walk a gimplified function and warn for functions whose return value is
7712 ignored and attribute((warn_unused_result)) is set. This is done before
7713 inlining, so we don't have to worry about that. */
7716 do_warn_unused_result (gimple_seq seq)
7719 gimple_stmt_iterator i;
7721 for (i = gsi_start (seq); !gsi_end_p (i); gsi_next (&i))
7723 gimple g = gsi_stmt (i);
7725 switch (gimple_code (g))
7728 do_warn_unused_result (gimple_bind_body (g));
7731 do_warn_unused_result (gimple_try_eval (g));
7732 do_warn_unused_result (gimple_try_cleanup (g));
7735 do_warn_unused_result (gimple_catch_handler (g));
7737 case GIMPLE_EH_FILTER:
7738 do_warn_unused_result (gimple_eh_filter_failure (g));
7742 if (gimple_call_lhs (g))
7745 /* This is a naked call, as opposed to a GIMPLE_CALL with an
7746 LHS. All calls whose value is ignored should be
7747 represented like this. Look for the attribute. */
7748 fdecl = gimple_call_fndecl (g);
7749 ftype = TREE_TYPE (TREE_TYPE (gimple_call_fn (g)));
7751 if (lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (ftype)))
7753 location_t loc = gimple_location (g);
7756 warning_at (loc, OPT_Wunused_result,
7757 "ignoring return value of %qD, "
7758 "declared with attribute warn_unused_result",
7761 warning_at (loc, OPT_Wunused_result,
7762 "ignoring return value of function "
7763 "declared with attribute warn_unused_result");
7768 /* Not a container, not a call, or a call whose value is used. */
7775 run_warn_unused_result (void)
7777 do_warn_unused_result (gimple_body (current_function_decl));
7782 gate_warn_unused_result (void)
7784 return flag_warn_unused_result;
7787 struct gimple_opt_pass pass_warn_unused_result =
7791 "*warn_unused_result", /* name */
7792 gate_warn_unused_result, /* gate */
7793 run_warn_unused_result, /* execute */
7796 0, /* static_pass_number */
7797 TV_NONE, /* tv_id */
7798 PROP_gimple_any, /* properties_required */
7799 0, /* properties_provided */
7800 0, /* properties_destroyed */
7801 0, /* todo_flags_start */
7802 0, /* todo_flags_finish */