1 /* Declarations for C++ name lookup routines.
2 Copyright (C) 2003, 2004, 2005, 2007, 2008 Free Software Foundation, Inc.
3 Contributed by Gabriel Dos Reis <gdr@integrable-solutions.net>
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License 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 #ifndef GCC_CP_NAME_LOOKUP_H
22 #define GCC_CP_NAME_LOOKUP_H
26 /* The type of dictionary used to map names to types declared at
28 typedef struct binding_table_s *binding_table;
29 typedef struct binding_entry_s *binding_entry;
31 /* The type of a routine repeatedly called by binding_table_foreach. */
32 typedef void (*bt_foreach_proc) (binding_entry, void *);
34 struct binding_entry_s GTY(())
41 /* These macros indicate the initial chains count for binding_table. */
42 #define SCOPE_DEFAULT_HT_SIZE (1 << 3)
43 #define CLASS_SCOPE_HT_SIZE (1 << 3)
44 #define NAMESPACE_ORDINARY_HT_SIZE (1 << 5)
45 #define NAMESPACE_STD_HT_SIZE (1 << 8)
46 #define GLOBAL_SCOPE_HT_SIZE (1 << 8)
48 extern void binding_table_foreach (binding_table, bt_foreach_proc, void *);
49 extern binding_entry binding_table_find (binding_table, tree);
51 /* Datatype that represents binding established by a declaration between
52 a name and a C++ entity. */
53 typedef struct cxx_binding cxx_binding;
55 /* The datatype used to implement C++ scope. */
56 typedef struct cp_binding_level cxx_scope;
58 /* Nonzero if this binding is for a local scope, as opposed to a class
59 or namespace scope. */
60 #define LOCAL_BINDING_P(NODE) ((NODE)->is_local)
62 /* True if NODE->value is from a base class of the class which is
63 currently being defined. */
64 #define INHERITED_VALUE_BINDING_P(NODE) ((NODE)->value_is_inherited)
66 struct cxx_binding GTY(())
68 /* Link to chain together various bindings for this name. */
69 cxx_binding *previous;
70 /* The non-type entity this name is bound to. */
72 /* The type entity this name is bound to. */
74 /* The scope at which this binding was made. */
76 unsigned value_is_inherited : 1;
77 unsigned is_local : 1;
80 /* Datatype used to temporarily save C++ bindings (for implicit
81 instantiations purposes and like). Implemented in decl.c. */
82 typedef struct cxx_saved_binding GTY(())
84 /* The name of the current binding. */
86 /* The binding we're saving. */
91 DEF_VEC_O(cxx_saved_binding);
92 DEF_VEC_ALLOC_O(cxx_saved_binding,gc);
94 extern tree identifier_type_value (tree);
95 extern void set_identifier_type_value (tree, tree);
96 extern void pop_binding (tree, tree);
97 extern tree constructor_name (tree);
98 extern bool constructor_name_p (tree, tree);
100 /* The kinds of scopes we recognize. */
101 typedef enum scope_kind {
102 sk_block = 0, /* An ordinary block scope. This enumerator must
103 have the value zero because "cp_binding_level"
104 is initialized by using "memset" to set the
105 contents to zero, and the default scope kind
107 sk_cleanup, /* A scope for (pseudo-)scope for cleanup. It is
108 pseudo in that it is transparent to name lookup
110 sk_try, /* A try-block. */
111 sk_catch, /* A catch-block. */
112 sk_for, /* The scope of the variable declared in a
113 for-init-statement. */
114 sk_function_parms, /* The scope containing function parameters. */
115 sk_class, /* The scope containing the members of a class. */
116 sk_scoped_enum, /* The scope containing the enumertors of a C++0x
117 scoped enumeration. */
118 sk_namespace, /* The scope containing the members of a
119 namespace, including the global scope. */
120 sk_template_parms, /* A scope for template parameters. */
121 sk_template_spec, /* Like sk_template_parms, but for an explicit
122 specialization. Since, by definition, an
123 explicit specialization is introduced by
124 "template <>", this scope is always empty. */
125 sk_omp /* An OpenMP structured block. */
128 /* The scope where the class/struct/union/enum tag applies. */
129 typedef enum tag_scope {
130 ts_current = 0, /* Current scope only. This is for the
131 class-key identifier;
132 case mentioned in [basic.lookup.elab]/2,
133 or the class/enum definition
134 class-key identifier { ... }; */
135 ts_global = 1, /* All scopes. This is the 3.4.1
136 [basic.lookup.unqual] lookup mentioned
137 in [basic.lookup.elab]/2. */
138 ts_within_enclosing_non_class = 2 /* Search within enclosing non-class
139 only, for friend class lookup
140 according to [namespace.memdef]/3
141 and [class.friend]/9. */
144 typedef struct cp_class_binding GTY(())
147 /* The bound name. */
151 DEF_VEC_O(cp_class_binding);
152 DEF_VEC_ALLOC_O(cp_class_binding,gc);
154 /* For each binding contour we allocate a binding_level structure
155 which records the names defined in that contour.
158 1) one for each function definition,
159 where internal declarations of the parameters appear.
160 2) one for each compound statement,
161 to record its declarations.
163 The current meaning of a name can be found by searching the levels
164 from the current one out to the global one.
166 Off to the side, may be the class_binding_level. This exists only
167 to catch class-local declarations. It is otherwise nonexistent.
169 Also there may be binding levels that catch cleanups that must be
170 run when exceptions occur. Thus, to see whether a name is bound in
171 the current scope, it is not enough to look in the
172 CURRENT_BINDING_LEVEL. You should use lookup_name_current_level
175 /* Note that the information in the `names' component of the global contour
176 is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers. */
178 struct cp_binding_level GTY(())
180 /* A chain of _DECL nodes for all variables, constants, functions,
181 and typedef types. These are in the reverse of the order
182 supplied. There may be OVERLOADs on this list, too, but they
183 are wrapped in TREE_LISTs; the TREE_VALUE is the OVERLOAD. */
186 /* Count of elements in names chain. */
189 /* A chain of NAMESPACE_DECL nodes. */
192 /* An array of static functions and variables (for namespaces only) */
193 VEC(tree,gc) *static_decls;
195 /* A list of USING_DECL nodes. */
198 /* A list of used namespaces. PURPOSE is the namespace,
199 VALUE the common ancestor with this binding_level's namespace. */
200 tree using_directives;
202 /* For the binding level corresponding to a class, the entities
203 declared in the class or its base classes. */
204 VEC(cp_class_binding,gc) *class_shadowed;
206 /* Similar to class_shadowed, but for IDENTIFIER_TYPE_VALUE, and
207 is used for all binding levels. The TREE_PURPOSE is the name of
208 the entity, the TREE_TYPE is the associated type. In addition
209 the TREE_VALUE is the IDENTIFIER_TYPE_VALUE before we entered
213 /* A TREE_LIST. Each TREE_VALUE is the LABEL_DECL for a local
214 label in this scope. The TREE_PURPOSE is the previous value of
215 the IDENTIFIER_LABEL VALUE. */
216 tree shadowed_labels;
218 /* For each level (except not the global one),
219 a chain of BLOCK nodes for all the levels
220 that were entered and exited one level down. */
223 /* The entity (namespace, class, function) the scope of which this
224 binding contour corresponds to. Otherwise NULL. */
227 /* The binding level which this one is contained in (inherits from). */
228 struct cp_binding_level *level_chain;
230 /* List of VAR_DECLS saved from a previous for statement.
231 These would be dead in ISO-conforming code, but might
232 be referenced in ARM-era code. These are stored in a
233 TREE_LIST; the TREE_VALUE is the actual declaration. */
234 tree dead_vars_from_for;
236 /* STATEMENT_LIST for statements in this binding contour.
237 Only used at present for SK_CLEANUP temporary bindings. */
240 /* Binding depth at which this level began. */
243 /* The kind of scope that this object represents. However, a
244 SK_TEMPLATE_SPEC scope is represented with KIND set to
245 SK_TEMPLATE_PARMS and EXPLICIT_SPEC_P set to true. */
246 ENUM_BITFIELD (scope_kind) kind : 4;
248 /* True if this scope is an SK_TEMPLATE_SPEC scope. This field is
249 only valid if KIND == SK_TEMPLATE_PARMS. */
250 BOOL_BITFIELD explicit_spec_p : 1;
252 /* true means make a BLOCK for this level regardless of all else. */
255 /* Nonzero if this level can safely have additional
256 cleanup-needing variables added to it. */
257 unsigned more_cleanups_ok : 1;
258 unsigned have_cleanups : 1;
260 /* 24 bits left to fill a 32-bit word. */
263 /* The binding level currently in effect. */
265 #define current_binding_level \
266 (*(cfun && cp_function_chain && cp_function_chain->bindings \
267 ? &cp_function_chain->bindings \
268 : &scope_chain->bindings))
270 /* The binding level of the current class, if any. */
272 #define class_binding_level scope_chain->class_bindings
274 /* The tree node representing the global scope. */
275 extern GTY(()) tree global_namespace;
276 extern GTY(()) tree global_scope_name;
278 /* Indicates that there is a type value in some namespace, although
279 that is not necessarily in scope at the moment. */
281 extern GTY(()) tree global_type_node;
283 /* True if SCOPE designates the global scope binding contour. */
284 #define global_scope_p(SCOPE) \
285 ((SCOPE) == NAMESPACE_LEVEL (global_namespace))
287 extern cxx_scope *leave_scope (void);
288 extern bool kept_level_p (void);
289 extern int global_bindings_p (void);
290 extern bool toplevel_bindings_p (void);
291 extern bool namespace_bindings_p (void);
292 extern bool template_parm_scope_p (void);
293 extern scope_kind innermost_scope_kind (void);
294 extern cxx_scope *begin_scope (scope_kind, tree);
295 extern void print_binding_stack (void);
296 extern void push_to_top_level (void);
297 extern void pop_from_top_level (void);
298 extern void pop_everything (void);
299 extern void keep_next_level (bool);
300 extern bool is_ancestor (tree, tree);
301 extern tree push_scope (tree);
302 extern void pop_scope (tree);
303 extern tree push_inner_scope (tree);
304 extern void pop_inner_scope (tree, tree);
305 extern void push_binding_level (struct cp_binding_level *);
307 extern void push_namespace (tree);
308 extern void pop_namespace (void);
309 extern void push_nested_namespace (tree);
310 extern void pop_nested_namespace (tree);
311 extern bool handle_namespace_attrs (tree, tree);
312 extern void pushlevel_class (void);
313 extern void poplevel_class (void);
314 extern tree pushdecl_with_scope (tree, cxx_scope *, bool);
315 extern tree lookup_name_prefer_type (tree, int);
316 extern tree lookup_name_real (tree, int, int, bool, int, int);
317 extern tree lookup_type_scope (tree, tag_scope);
318 extern tree namespace_binding (tree, tree);
319 extern void set_namespace_binding (tree, tree, tree);
320 extern bool hidden_name_p (tree);
321 extern tree remove_hidden_names (tree);
322 extern tree lookup_qualified_name (tree, tree, bool, bool);
323 extern tree lookup_name_nonclass (tree);
324 extern tree lookup_name_innermost_nonclass_level (tree);
325 extern tree lookup_function_nonclass (tree, tree, bool);
326 extern void push_local_binding (tree, tree, int);
327 extern bool pushdecl_class_level (tree);
328 extern tree pushdecl_namespace_level (tree, bool);
329 extern bool push_class_level_binding (tree, tree);
330 extern tree getdecls (void);
331 extern tree cp_namespace_decls (tree);
332 extern void set_decl_namespace (tree, tree, bool);
333 extern void push_decl_namespace (tree);
334 extern void pop_decl_namespace (void);
335 extern void do_namespace_alias (tree, tree);
336 extern void do_toplevel_using_decl (tree, tree, tree);
337 extern void do_local_using_decl (tree, tree, tree);
338 extern tree do_class_using_decl (tree, tree);
339 extern void do_using_directive (tree);
340 extern tree lookup_arg_dependent (tree, tree, tree);
341 extern bool is_associated_namespace (tree, tree);
342 extern void parse_using_directive (tree, tree);
343 extern tree innermost_non_namespace_value (tree);
344 extern cxx_binding *outer_binding (tree, cxx_binding *, bool);
345 extern void cp_emit_debug_info_for_using (tree, tree);
347 /* Set *DECL to the (non-hidden) declaration for ID at global scope,
348 if present and return true; otherwise return false. */
351 get_global_value_if_present (tree id, tree *decl)
353 tree global_value = namespace_binding (id, global_namespace);
355 *decl = global_value;
356 return global_value != NULL;
359 /* True is the binding of IDENTIFIER at global scope names a type. */
362 is_typename_at_global_scope (tree id)
364 tree global_value = namespace_binding (id, global_namespace);
366 return global_value && TREE_CODE (global_value) == TYPE_DECL;
369 #endif /* GCC_CP_NAME_LOOKUP_H */