1/* Declarations for C++ name lookup routines.
2 Copyright (C) 2003-2017 Free Software Foundation, Inc.
3 Contributed by Gabriel Dos Reis <gdr@integrable-solutions.net>
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 3, or (at your option)
10any later version.
11
12GCC is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING3. If not see
19<http://www.gnu.org/licenses/>. */
20
21#ifndef GCC_CP_NAME_LOOKUP_H
22#define GCC_CP_NAME_LOOKUP_H
23
24#include "c-family/c-common.h"
25
26/* The type of dictionary used to map names to types declared at
27 a given scope. */
28typedef struct binding_table_s *binding_table;
29typedef struct binding_entry_s *binding_entry;
30
31/* The type of a routine repeatedly called by binding_table_foreach. */
32typedef void (*bt_foreach_proc) (binding_entry, void *);
33
34struct GTY(()) binding_entry_s {
35 binding_entry chain;
36 tree name;
37 tree type;
38};
39
40/* These macros indicate the initial chains count for binding_table. */
41#define SCOPE_DEFAULT_HT_SIZE (1 << 3)
42#define CLASS_SCOPE_HT_SIZE (1 << 3)
43#define NAMESPACE_ORDINARY_HT_SIZE (1 << 5)
44#define NAMESPACE_STD_HT_SIZE (1 << 8)
45#define GLOBAL_SCOPE_HT_SIZE (1 << 8)
46
47extern void binding_table_foreach (binding_table, bt_foreach_proc, void *);
48extern binding_entry binding_table_find (binding_table, tree);
49
50/* Datatype that represents binding established by a declaration between
51 a name and a C++ entity. */
52typedef struct cxx_binding cxx_binding;
53
54/* The datatype used to implement C++ scope. */
55typedef struct cp_binding_level cp_binding_level;
56
57/* Nonzero if this binding is for a local scope, as opposed to a class
58 or namespace scope. */
59#define LOCAL_BINDING_P(NODE) ((NODE)->is_local)
60
61/* True if NODE->value is from a base class of the class which is
62 currently being defined. */
63#define INHERITED_VALUE_BINDING_P(NODE) ((NODE)->value_is_inherited)
64
65struct GTY(()) cxx_binding {
66 /* Link to chain together various bindings for this name. */
67 cxx_binding *previous;
68 /* The non-type entity this name is bound to. */
69 tree value;
70 /* The type entity this name is bound to. */
71 tree type;
72 /* The scope at which this binding was made. */
73 cp_binding_level *scope;
74 unsigned value_is_inherited : 1;
75 unsigned is_local : 1;
76};
77
78/* Datatype used to temporarily save C++ bindings (for implicit
79 instantiations purposes and like). Implemented in decl.c. */
80struct GTY(()) cxx_saved_binding {
81 /* The name of the current binding. */
82 tree identifier;
83 /* The binding we're saving. */
84 cxx_binding *binding;
85 tree real_type_value;
86};
87
88
89extern tree identifier_type_value (tree);
90extern void set_identifier_type_value (tree, tree);
91extern void push_binding (tree, tree, cp_binding_level*);
92extern void pop_local_binding (tree, tree);
93extern void pop_bindings_and_leave_scope (void);
94extern tree constructor_name (tree);
95extern bool constructor_name_p (tree, tree);
96
97/* The kinds of scopes we recognize. */
98enum scope_kind {
99 sk_block = 0, /* An ordinary block scope. This enumerator must
100 have the value zero because "cp_binding_level"
101 is initialized by using "memset" to set the
102 contents to zero, and the default scope kind
103 is "sk_block". */
104 sk_cleanup, /* A scope for (pseudo-)scope for cleanup. It is
105 pseudo in that it is transparent to name lookup
106 activities. */
107 sk_try, /* A try-block. */
108 sk_catch, /* A catch-block. */
109 sk_for, /* The scope of the variable declared in a
110 init-statement. */
111 sk_cond, /* The scope of the variable declared in the condition
112 of an if or switch statement. */
113 sk_function_parms, /* The scope containing function parameters. */
114 sk_class, /* The scope containing the members of a class. */
115 sk_scoped_enum, /* The scope containing the enumertors of a C++0x
116 scoped enumeration. */
117 sk_namespace, /* The scope containing the members of a
118 namespace, including the global scope. */
119 sk_template_parms, /* A scope for template parameters. */
120 sk_template_spec, /* Like sk_template_parms, but for an explicit
121 specialization. Since, by definition, an
122 explicit specialization is introduced by
123 "template <>", this scope is always empty. */
124 sk_transaction, /* A synchronized or atomic statement. */
125 sk_omp /* An OpenMP structured block. */
126};
127
128/* The scope where the class/struct/union/enum tag applies. */
129enum 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. */
142 ts_lambda = 3 /* Declaring a lambda closure. */
143};
144
145struct GTY(()) cp_class_binding {
146 cxx_binding *base;
147 /* The bound name. */
148 tree identifier;
149};
150
151/* For each binding contour we allocate a binding_level structure
152 which records the names defined in that contour.
153 Contours include:
154 0) the global one
155 1) one for each function definition,
156 where internal declarations of the parameters appear.
157 2) one for each compound statement,
158 to record its declarations.
159
160 The current meaning of a name can be found by searching the levels
161 from the current one out to the global one.
162
163 Off to the side, may be the class_binding_level. This exists only
164 to catch class-local declarations. It is otherwise nonexistent.
165
166 Also there may be binding levels that catch cleanups that must be
167 run when exceptions occur. Thus, to see whether a name is bound in
168 the current scope, it is not enough to look in the
169 CURRENT_BINDING_LEVEL. You should use lookup_name_current_level
170 instead. */
171
172struct GTY(()) cp_binding_level {
173 /* A chain of _DECL nodes for all variables, constants, functions,
174 and typedef types. These are in the reverse of the order
175 supplied. There may be OVERLOADs on this list, too, but they
176 are wrapped in TREE_LISTs; the TREE_VALUE is the OVERLOAD. */
177 tree names;
178
179 /* A list of USING_DECL nodes. */
180 tree usings;
181
182 /* Using directives. */
183 vec<tree, va_gc> *using_directives;
184
185 /* For the binding level corresponding to a class, the entities
186 declared in the class or its base classes. */
187 vec<cp_class_binding, va_gc> *class_shadowed;
188
189 /* Similar to class_shadowed, but for IDENTIFIER_TYPE_VALUE, and
190 is used for all binding levels. The TREE_PURPOSE is the name of
191 the entity, the TREE_TYPE is the associated type. In addition
192 the TREE_VALUE is the IDENTIFIER_TYPE_VALUE before we entered
193 the class. */
194 tree type_shadowed;
195
196 /* For each level (except not the global one),
197 a chain of BLOCK nodes for all the levels
198 that were entered and exited one level down. */
199 tree blocks;
200
201 /* The entity (namespace, class, function) the scope of which this
202 binding contour corresponds to. Otherwise NULL. */
203 tree this_entity;
204
205 /* The binding level which this one is contained in (inherits from). */
206 cp_binding_level *level_chain;
207
208 /* List of VAR_DECLS saved from a previous for statement.
209 These would be dead in ISO-conforming code, but might
210 be referenced in ARM-era code. */
211 vec<tree, va_gc> *dead_vars_from_for;
212
213 /* STATEMENT_LIST for statements in this binding contour.
214 Only used at present for SK_CLEANUP temporary bindings. */
215 tree statement_list;
216
217 /* Binding depth at which this level began. */
218 int binding_depth;
219
220 /* The kind of scope that this object represents. However, a
221 SK_TEMPLATE_SPEC scope is represented with KIND set to
222 SK_TEMPLATE_PARMS and EXPLICIT_SPEC_P set to true. */
223 ENUM_BITFIELD (scope_kind) kind : 4;
224
225 /* True if this scope is an SK_TEMPLATE_SPEC scope. This field is
226 only valid if KIND == SK_TEMPLATE_PARMS. */
227 BOOL_BITFIELD explicit_spec_p : 1;
228
229 /* true means make a BLOCK for this level regardless of all else. */
230 unsigned keep : 1;
231
232 /* Nonzero if this level can safely have additional
233 cleanup-needing variables added to it. */
234 unsigned more_cleanups_ok : 1;
235 unsigned have_cleanups : 1;
236
237 /* Transient state set if this scope is of sk_class kind
238 and is in the process of defining 'this_entity'. Reset
239 on leaving the class definition to allow for the scope
240 to be subsequently re-used as a non-defining scope for
241 'this_entity'. */
242 unsigned defining_class_p : 1;
243
244 /* 23 bits left to fill a 32-bit word. */
245};
246
247/* The binding level currently in effect. */
248
249#define current_binding_level \
250 (*(cfun && cp_function_chain && cp_function_chain->bindings \
251 ? &cp_function_chain->bindings \
252 : &scope_chain->bindings))
253
254/* The binding level of the current class, if any. */
255
256#define class_binding_level scope_chain->class_bindings
257
258/* True if SCOPE designates the global scope binding contour. */
259#define global_scope_p(SCOPE) \
260 ((SCOPE) == NAMESPACE_LEVEL (global_namespace))
261
262extern cp_binding_level *leave_scope (void);
263extern bool kept_level_p (void);
264extern bool global_bindings_p (void);
265extern bool toplevel_bindings_p (void);
266extern bool namespace_bindings_p (void);
267extern bool local_bindings_p (void);
268extern bool template_parm_scope_p (void);
269extern scope_kind innermost_scope_kind (void);
270extern cp_binding_level *begin_scope (scope_kind, tree);
271extern void print_binding_stack (void);
272extern void pop_everything (void);
273extern void keep_next_level (bool);
274extern bool is_ancestor (tree ancestor, tree descendant);
275extern bool is_nested_namespace (tree parent, tree descendant,
276 bool inline_only = false);
277extern tree push_scope (tree);
278extern void pop_scope (tree);
279extern tree push_inner_scope (tree);
280extern void pop_inner_scope (tree, tree);
281extern void push_binding_level (cp_binding_level *);
282
283extern bool handle_namespace_attrs (tree, tree);
284extern void pushlevel_class (void);
285extern void poplevel_class (void);
286extern tree lookup_name_prefer_type (tree, int);
287extern tree lookup_name_real (tree, int, int, bool, int, int);
288extern tree lookup_type_scope (tree, tag_scope);
289extern tree get_namespace_binding (tree ns, tree id);
290extern void set_global_binding (tree decl);
291inline tree get_global_binding (tree id)
292{
293 return get_namespace_binding (NULL_TREE, id);
294}
295extern tree lookup_qualified_name (tree, tree, int, bool, /*hidden*/bool = false);
296extern tree lookup_name_nonclass (tree);
297extern bool is_local_extern (tree);
298extern bool pushdecl_class_level (tree);
299extern tree pushdecl_namespace_level (tree, bool);
300extern bool push_class_level_binding (tree, tree);
301extern tree get_local_decls ();
302extern int function_parm_depth (void);
303extern tree cp_namespace_decls (tree);
304extern void set_decl_namespace (tree, tree, bool);
305extern void push_decl_namespace (tree);
306extern void pop_decl_namespace (void);
307extern void do_namespace_alias (tree, tree);
308extern tree do_class_using_decl (tree, tree);
309extern tree lookup_arg_dependent (tree, tree, vec<tree, va_gc> *);
310extern tree search_anon_aggr (tree, tree);
311extern tree get_class_binding_direct (tree, tree, int type_or_fns = -1);
312extern tree get_class_binding (tree, tree, int type_or_fns = -1);
313extern tree *get_member_slot (tree klass, tree name);
314extern void resort_type_member_vec (void *, void *,
315 gt_pointer_operator, void *);
316extern void set_class_bindings (tree, unsigned extra = 0);
317extern void insert_late_enum_def_bindings (tree, tree);
318extern tree innermost_non_namespace_value (tree);
319extern cxx_binding *outer_binding (tree, cxx_binding *, bool);
320extern void cp_emit_debug_info_for_using (tree, tree);
321
322extern void finish_namespace_using_decl (tree, tree, tree);
323extern void finish_local_using_decl (tree, tree, tree);
324extern void finish_namespace_using_directive (tree, tree);
325extern void finish_local_using_directive (tree, tree);
326extern tree pushdecl (tree, bool is_friend = false);
327extern tree pushdecl_outermost_localscope (tree);
328extern tree pushdecl_top_level (tree, bool is_friend = false);
329extern tree pushdecl_top_level_and_finish (tree, tree);
330extern tree pushtag (tree, tree, tag_scope);
331extern int push_namespace (tree, bool make_inline = false);
332extern void pop_namespace (void);
333extern void push_nested_namespace (tree);
334extern void pop_nested_namespace (tree);
335extern void push_to_top_level (void);
336extern void pop_from_top_level (void);
337
338#endif /* GCC_CP_NAME_LOOKUP_H */
339