1/* Declarations for C++ name lookup routines. 2 Copyright (C) 2003-2015 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. */ 80typedef struct 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} cxx_saved_binding; 87 88 89extern tree identifier_type_value (tree); 90extern void set_identifier_type_value (tree, tree); 91extern void pop_binding (tree, tree); 92extern void pop_bindings_and_leave_scope (void); 93extern tree constructor_name (tree); 94extern bool constructor_name_p (tree, tree); 95 96/* The kinds of scopes we recognize. */ 97typedef enum scope_kind { 98 sk_block = 0, /* An ordinary block scope. This enumerator must 99 have the value zero because "cp_binding_level" 100 is initialized by using "memset" to set the 101 contents to zero, and the default scope kind 102 is "sk_block". */ 103 sk_cleanup, /* A scope for (pseudo-)scope for cleanup. It is 104 pseudo in that it is transparent to name lookup 105 activities. */ 106 sk_try, /* A try-block. */ 107 sk_catch, /* A catch-block. */ 108 sk_for, /* The scope of the variable declared in a 109 for-init-statement. */ 110 sk_cond, /* The scope of the variable declared in the condition 111 of an if or switch statement. */ 112 sk_function_parms, /* The scope containing function parameters. */ 113 sk_class, /* The scope containing the members of a class. */ 114 sk_scoped_enum, /* The scope containing the enumertors of a C++0x 115 scoped enumeration. */ 116 sk_namespace, /* The scope containing the members of a 117 namespace, including the global scope. */ 118 sk_template_parms, /* A scope for template parameters. */ 119 sk_template_spec, /* Like sk_template_parms, but for an explicit 120 specialization. Since, by definition, an 121 explicit specialization is introduced by 122 "template <>", this scope is always empty. */ 123 sk_omp /* An OpenMP structured block. */ 124} scope_kind; 125 126/* The scope where the class/struct/union/enum tag applies. */ 127typedef enum tag_scope { 128 ts_current = 0, /* Current scope only. This is for the 129 class-key identifier; 130 case mentioned in [basic.lookup.elab]/2, 131 or the class/enum definition 132 class-key identifier { ... }; */ 133 ts_global = 1, /* All scopes. This is the 3.4.1 134 [basic.lookup.unqual] lookup mentioned 135 in [basic.lookup.elab]/2. */ 136 ts_within_enclosing_non_class = 2, /* Search within enclosing non-class 137 only, for friend class lookup 138 according to [namespace.memdef]/3 139 and [class.friend]/9. */ 140 ts_lambda = 3 /* Declaring a lambda closure. */ 141} tag_scope; 142 143typedef struct GTY(()) cp_class_binding { 144 cxx_binding *base; 145 /* The bound name. */ 146 tree identifier; 147} cp_class_binding; 148 149 150typedef struct GTY(()) cp_label_binding { 151 /* The bound LABEL_DECL. */ 152 tree label; 153 /* The previous IDENTIFIER_LABEL_VALUE. */ 154 tree prev_value; 155} cp_label_binding; 156 157 158/* For each binding contour we allocate a binding_level structure 159 which records the names defined in that contour. 160 Contours include: 161 0) the global one 162 1) one for each function definition, 163 where internal declarations of the parameters appear. 164 2) one for each compound statement, 165 to record its declarations. 166 167 The current meaning of a name can be found by searching the levels 168 from the current one out to the global one. 169 170 Off to the side, may be the class_binding_level. This exists only 171 to catch class-local declarations. It is otherwise nonexistent. 172 173 Also there may be binding levels that catch cleanups that must be 174 run when exceptions occur. Thus, to see whether a name is bound in 175 the current scope, it is not enough to look in the 176 CURRENT_BINDING_LEVEL. You should use lookup_name_current_level 177 instead. */ 178 179/* Note that the information in the `names' component of the global contour 180 is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers. */ 181 182struct GTY(()) cp_binding_level { 183 /* A chain of _DECL nodes for all variables, constants, functions, 184 and typedef types. These are in the reverse of the order 185 supplied. There may be OVERLOADs on this list, too, but they 186 are wrapped in TREE_LISTs; the TREE_VALUE is the OVERLOAD. */ 187 tree names; 188 189 /* A chain of NAMESPACE_DECL nodes. */ 190 tree namespaces; 191 192 /* An array of static functions and variables (for namespaces only) */ 193 vec<tree, va_gc> *static_decls; 194 195 /* A list of USING_DECL nodes. */ 196 tree usings; 197 198 /* A list of used namespaces. PURPOSE is the namespace, 199 VALUE the common ancestor with this binding_level's namespace. */ 200 tree using_directives; 201 202 /* For the binding level corresponding to a class, the entities 203 declared in the class or its base classes. */ 204 vec<cp_class_binding, va_gc> *class_shadowed; 205 206 /* 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 210 the class. */ 211 tree type_shadowed; 212 213 /* Similar to class_shadowed, but for IDENTIFIER_LABEL_VALUE, and 214 used for all binding levels. */ 215 vec<cp_label_binding, va_gc> *shadowed_labels; 216 217 /* For each level (except not the global one), 218 a chain of BLOCK nodes for all the levels 219 that were entered and exited one level down. */ 220 tree blocks; 221 222 /* The entity (namespace, class, function) the scope of which this 223 binding contour corresponds to. Otherwise NULL. */ 224 tree this_entity; 225 226 /* The binding level which this one is contained in (inherits from). */ 227 cp_binding_level *level_chain; 228 229 /* List of VAR_DECLS saved from a previous for statement. 230 These would be dead in ISO-conforming code, but might 231 be referenced in ARM-era code. */ 232 vec<tree, va_gc> *dead_vars_from_for; 233 234 /* STATEMENT_LIST for statements in this binding contour. 235 Only used at present for SK_CLEANUP temporary bindings. */ 236 tree statement_list; 237 238 /* Binding depth at which this level began. */ 239 int binding_depth; 240 241 /* The kind of scope that this object represents. However, a 242 SK_TEMPLATE_SPEC scope is represented with KIND set to 243 SK_TEMPLATE_PARMS and EXPLICIT_SPEC_P set to true. */ 244 ENUM_BITFIELD (scope_kind) kind : 4; 245 246 /* True if this scope is an SK_TEMPLATE_SPEC scope. This field is 247 only valid if KIND == SK_TEMPLATE_PARMS. */ 248 BOOL_BITFIELD explicit_spec_p : 1; 249 250 /* true means make a BLOCK for this level regardless of all else. */ 251 unsigned keep : 1; 252 253 /* Nonzero if this level can safely have additional 254 cleanup-needing variables added to it. */ 255 unsigned more_cleanups_ok : 1; 256 unsigned have_cleanups : 1; 257 258 /* Transient state set if this scope is of sk_class kind 259 and is in the process of defining 'this_entity'. Reset 260 on leaving the class definition to allow for the scope 261 to be subsequently re-used as a non-defining scope for 262 'this_entity'. */ 263 unsigned defining_class_p : 1; 264 265 /* 23 bits left to fill a 32-bit word. */ 266}; 267 268/* The binding level currently in effect. */ 269 270#define current_binding_level \ 271 (*(cfun && cp_function_chain && cp_function_chain->bindings \ 272 ? &cp_function_chain->bindings \ 273 : &scope_chain->bindings)) 274 275/* The binding level of the current class, if any. */ 276 277#define class_binding_level scope_chain->class_bindings 278 279/* The tree node representing the global scope. */ 280extern GTY(()) tree global_namespace; 281extern GTY(()) tree global_scope_name; 282 283/* Indicates that there is a type value in some namespace, although 284 that is not necessarily in scope at the moment. */ 285 286extern GTY(()) tree global_type_node; 287 288/* True if SCOPE designates the global scope binding contour. */ 289#define global_scope_p(SCOPE) \ 290 ((SCOPE) == NAMESPACE_LEVEL (global_namespace)) 291 292extern cp_binding_level *leave_scope (void); 293extern bool kept_level_p (void); 294extern bool global_bindings_p (void); 295extern bool toplevel_bindings_p (void); 296extern bool namespace_bindings_p (void); 297extern bool local_bindings_p (void); 298extern bool template_parm_scope_p (void); 299extern scope_kind innermost_scope_kind (void); 300extern cp_binding_level *begin_scope (scope_kind, tree); 301extern void print_binding_stack (void); 302extern void push_to_top_level (void); 303extern void pop_from_top_level (void); 304extern void pop_everything (void); 305extern void keep_next_level (bool); 306extern bool is_ancestor (tree, tree); 307extern tree push_scope (tree); 308extern void pop_scope (tree); 309extern tree push_inner_scope (tree); 310extern void pop_inner_scope (tree, tree); 311extern void push_binding_level (cp_binding_level *); 312 313extern void push_namespace (tree); 314extern void pop_namespace (void); 315extern void push_nested_namespace (tree); 316extern void pop_nested_namespace (tree); 317extern bool handle_namespace_attrs (tree, tree); 318extern void pushlevel_class (void); 319extern void poplevel_class (void); 320extern tree pushdecl_with_scope (tree, cp_binding_level *, bool); 321extern tree lookup_name_prefer_type (tree, int); 322extern tree lookup_name_real (tree, int, int, bool, int, int); 323extern tree lookup_type_scope (tree, tag_scope); 324extern tree namespace_binding (tree, tree); 325extern void set_namespace_binding (tree, tree, tree); 326extern bool hidden_name_p (tree); 327extern tree remove_hidden_names (tree); 328extern tree lookup_qualified_name (tree, tree, bool, bool); 329extern tree lookup_name_nonclass (tree); 330extern tree lookup_name_innermost_nonclass_level (tree); 331extern bool is_local_extern (tree); 332extern tree lookup_function_nonclass (tree, vec<tree, va_gc> *, bool); 333extern void push_local_binding (tree, tree, int); 334extern bool pushdecl_class_level (tree); 335extern tree pushdecl_namespace_level (tree, bool); 336extern bool push_class_level_binding (tree, tree); 337extern tree getdecls (void); 338extern int function_parm_depth (void); 339extern tree cp_namespace_decls (tree); 340extern void set_decl_namespace (tree, tree, bool); 341extern void push_decl_namespace (tree); 342extern void pop_decl_namespace (void); 343extern void do_namespace_alias (tree, tree); 344extern void do_toplevel_using_decl (tree, tree, tree); 345extern void do_local_using_decl (tree, tree, tree); 346extern tree do_class_using_decl (tree, tree); 347extern void do_using_directive (tree); 348extern tree lookup_arg_dependent (tree, tree, vec<tree, va_gc> *); 349extern bool is_associated_namespace (tree, tree); 350extern void parse_using_directive (tree, tree); 351extern tree innermost_non_namespace_value (tree); 352extern cxx_binding *outer_binding (tree, cxx_binding *, bool); 353extern void cp_emit_debug_info_for_using (tree, tree); 354 355/* Set *DECL to the (non-hidden) declaration for ID at global scope, 356 if present and return true; otherwise return false. */ 357 358inline bool 359get_global_value_if_present (tree id, tree *decl) 360{ 361 tree global_value = namespace_binding (id, global_namespace); 362 if (global_value) 363 *decl = global_value; 364 return global_value != NULL; 365} 366 367/* True is the binding of IDENTIFIER at global scope names a type. */ 368 369inline bool 370is_typename_at_global_scope (tree id) 371{ 372 tree global_value = namespace_binding (id, global_namespace); 373 374 return global_value && TREE_CODE (global_value) == TYPE_DECL; 375} 376 377#endif /* GCC_CP_NAME_LOOKUP_H */ 378