PR 61187 Fix use of uninitialized memory.
[official-gcc.git] / gcc / ipa-ref.c
blobdf84c9cc1af352118fc1ddbbeda611cc86a36d2f
1 /* Interprocedural reference lists.
2 Copyright (C) 2010-2014 Free Software Foundation, Inc.
3 Contributed by Jan Hubicka
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 #include "config.h"
22 #include "system.h"
23 #include "coretypes.h"
24 #include "tree.h"
25 #include "ggc.h"
26 #include "target.h"
27 #include "cgraph.h"
28 #include "ipa-utils.h"
30 static const char *ipa_ref_use_name[] = {"read","write","addr","alias"};
32 /* Return ipa reference from REFERING_NODE or REFERING_VARPOOL_NODE
33 to REFERED_NODE or REFERED_VARPOOL_NODE. USE_TYPE specify type
34 of the use and STMT the statement (if it exists). */
36 struct ipa_ref *
37 ipa_record_reference (symtab_node *referring_node,
38 symtab_node *referred_node,
39 enum ipa_ref_use use_type, gimple stmt)
41 struct ipa_ref *ref, *ref2;
42 struct ipa_ref_list *list, *list2;
43 ipa_ref_t *old_references;
45 gcc_checking_assert (!stmt || is_a <cgraph_node *> (referring_node));
46 gcc_checking_assert (use_type != IPA_REF_ALIAS || !stmt);
48 list = &referring_node->ref_list;
49 old_references = vec_safe_address (list->references);
50 vec_safe_grow (list->references, vec_safe_length (list->references) + 1);
51 ref = &list->references->last ();
53 list2 = &referred_node->ref_list;
54 list2->referring.safe_push (ref);
55 ref->referred_index = list2->referring.length () - 1;
56 ref->referring = referring_node;
57 ref->referred = referred_node;
58 ref->stmt = stmt;
59 ref->lto_stmt_uid = 0;
60 ref->use = use_type;
61 ref->speculative = 0;
63 /* If vector was moved in memory, update pointers. */
64 if (old_references != list->references->address ())
66 int i;
67 for (i = 0; ipa_ref_list_reference_iterate (list, i, ref2); i++)
68 ipa_ref_referred_ref_list (ref2)->referring[ref2->referred_index] = ref2;
70 return ref;
73 /* If VAL is a reference to a function or a variable, add a reference from
74 REFERRING_NODE to the corresponding symbol table node. USE_TYPE specify
75 type of the use and STMT the statement (if it exists). Return the new
76 reference or NULL if none was created. */
78 struct ipa_ref *
79 ipa_maybe_record_reference (symtab_node *referring_node, tree val,
80 enum ipa_ref_use use_type, gimple stmt)
82 STRIP_NOPS (val);
83 if (TREE_CODE (val) != ADDR_EXPR)
84 return NULL;
85 val = get_base_var (val);
86 if (val && (TREE_CODE (val) == FUNCTION_DECL
87 || TREE_CODE (val) == VAR_DECL))
89 symtab_node *referred = symtab_get_node (val);
90 gcc_checking_assert (referred);
91 return ipa_record_reference (referring_node, referred,
92 use_type, stmt);
94 return NULL;
97 /* Remove reference REF. */
99 void
100 ipa_remove_reference (struct ipa_ref *ref)
102 struct ipa_ref_list *list = ipa_ref_referred_ref_list (ref);
103 struct ipa_ref_list *list2 = ipa_ref_referring_ref_list (ref);
104 vec<ipa_ref_t, va_gc> *old_references = list2->references;
105 struct ipa_ref *last;
107 gcc_assert (list->referring[ref->referred_index] == ref);
108 last = list->referring.last ();
109 if (ref != last)
111 list->referring[ref->referred_index] = list->referring.last ();
112 list->referring[ref->referred_index]->referred_index
113 = ref->referred_index;
115 list->referring.pop ();
117 last = &list2->references->last ();
118 if (ref != last)
120 *ref = *last;
121 ipa_ref_referred_ref_list (ref)->referring[ref->referred_index] = ref;
123 list2->references->pop ();
124 gcc_assert (list2->references == old_references);
127 /* Remove all references in ref list LIST. */
129 void
130 ipa_remove_all_references (struct ipa_ref_list *list)
132 while (vec_safe_length (list->references))
133 ipa_remove_reference (&list->references->last ());
134 vec_free (list->references);
137 /* Remove all references in ref list LIST. */
139 void
140 ipa_remove_all_referring (struct ipa_ref_list *list)
142 while (list->referring.length ())
143 ipa_remove_reference (list->referring.last ());
144 list->referring.release ();
147 /* Dump references in LIST to FILE. */
149 void
150 ipa_dump_references (FILE * file, struct ipa_ref_list *list)
152 struct ipa_ref *ref;
153 int i;
154 for (i = 0; ipa_ref_list_reference_iterate (list, i, ref); i++)
156 fprintf (file, "%s/%i (%s)",
157 ref->referred->asm_name (),
158 ref->referred->order,
159 ipa_ref_use_name [ref->use]);
160 if (ref->speculative)
161 fprintf (file, " (speculative)");
163 fprintf (file, "\n");
166 /* Dump referring in LIST to FILE. */
168 void
169 ipa_dump_referring (FILE * file, struct ipa_ref_list *list)
171 struct ipa_ref *ref;
172 int i;
173 for (i = 0; ipa_ref_list_referring_iterate (list, i, ref); i++)
175 fprintf (file, "%s/%i (%s)",
176 ref->referring->asm_name (),
177 ref->referring->order,
178 ipa_ref_use_name [ref->use]);
179 if (ref->speculative)
180 fprintf (file, " (speculative)");
182 fprintf (file, "\n");
185 /* Clone reference REF to DEST_NODE and set its stmt to STMT. */
187 struct ipa_ref *
188 ipa_clone_ref (struct ipa_ref *ref,
189 symtab_node *dest_node,
190 gimple stmt)
192 bool speculative = ref->speculative;
193 unsigned int stmt_uid = ref->lto_stmt_uid;
194 struct ipa_ref *ref2;
196 ref2 = ipa_record_reference (dest_node,
197 ref->referred,
198 ref->use, stmt);
199 ref2->speculative = speculative;
200 ref2->lto_stmt_uid = stmt_uid;
201 return ref2;
204 /* Clone all references from SRC to DEST_NODE or DEST_VARPOOL_NODE. */
206 void
207 ipa_clone_references (symtab_node *dest_node,
208 struct ipa_ref_list *src)
210 struct ipa_ref *ref, *ref2;
211 int i;
212 for (i = 0; ipa_ref_list_reference_iterate (src, i, ref); i++)
214 bool speculative = ref->speculative;
215 unsigned int stmt_uid = ref->lto_stmt_uid;
217 ref2 = ipa_record_reference (dest_node,
218 ref->referred,
219 ref->use, ref->stmt);
220 ref2->speculative = speculative;
221 ref2->lto_stmt_uid = stmt_uid;
225 /* Clone all referring from SRC to DEST_NODE or DEST_VARPOOL_NODE. */
227 void
228 ipa_clone_referring (symtab_node *dest_node,
229 struct ipa_ref_list *src)
231 struct ipa_ref *ref, *ref2;
232 int i;
233 for (i = 0; ipa_ref_list_referring_iterate (src, i, ref); i++)
235 bool speculative = ref->speculative;
236 unsigned int stmt_uid = ref->lto_stmt_uid;
238 ref2 = ipa_record_reference (ref->referring,
239 dest_node,
240 ref->use, ref->stmt);
241 ref2->speculative = speculative;
242 ref2->lto_stmt_uid = stmt_uid;
246 /* Return true when execution of REF can lead to return from
247 function. */
248 bool
249 ipa_ref_cannot_lead_to_return (struct ipa_ref *ref)
251 return cgraph_node_cannot_return (ipa_ref_referring_node (ref));
254 /* Return true if list contains an alias. */
255 bool
256 ipa_ref_has_aliases_p (struct ipa_ref_list *ref_list)
258 struct ipa_ref *ref;
259 int i;
261 for (i = 0; ipa_ref_list_referring_iterate (ref_list, i, ref); i++)
262 if (ref->use == IPA_REF_ALIAS)
263 return true;
264 return false;
267 /* Find the structure describing a reference in REFERRING_NODE to REFERRED_NODE
268 and associated with statement STMT. */
270 struct ipa_ref *
271 ipa_find_reference (symtab_node *referring_node, symtab_node *referred_node,
272 gimple stmt, unsigned int lto_stmt_uid)
274 struct ipa_ref *r = NULL;
275 int i;
277 for (i = 0; ipa_ref_list_reference_iterate (&referring_node->ref_list, i, r); i++)
278 if (r->referred == referred_node
279 && !r->speculative
280 && ((stmt && r->stmt == stmt)
281 || (lto_stmt_uid && r->lto_stmt_uid == lto_stmt_uid)
282 || (!stmt && !lto_stmt_uid && !r->stmt && !r->lto_stmt_uid)))
283 return r;
284 return NULL;
287 /* Remove all references from REFERRING_NODE that are associated with statement
288 STMT. */
290 void
291 ipa_remove_stmt_references (symtab_node *referring_node, gimple stmt)
293 struct ipa_ref *r = NULL;
294 int i = 0;
296 while (ipa_ref_list_reference_iterate (&referring_node->ref_list, i, r))
297 if (r->stmt == stmt)
298 ipa_remove_reference (r);
299 else
300 i++;
303 /* Remove all stmt references in non-speculative references.
304 Those are not maintained during inlining & clonning.
305 The exception are speculative references that are updated along
306 with callgraph edges associated with them. */
308 void
309 ipa_clear_stmts_in_references (symtab_node *referring_node)
311 struct ipa_ref *r = NULL;
312 int i;
314 for (i = 0; ipa_ref_list_reference_iterate (&referring_node->ref_list, i, r); i++)
315 if (!r->speculative)
317 r->stmt = NULL;
318 r->lto_stmt_uid = 0;