1/* Declarations for C++ name lookup routines. 2 Copyright (C) 2003, 2004, 2005 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 2, 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 COPYING. If not, write to 19the Free Software Foundation, 51 Franklin Street, Fifth Floor, 20Boston, MA 02110-1301, USA. */ 21 22#ifndef GCC_CP_NAME_LOOKUP_H 23#define GCC_CP_NAME_LOOKUP_H 24 25#include "c-common.h" 26 27/* The type of dictionary used to map names to types declared at 28 a given scope. */ 29typedef struct binding_table_s *binding_table; 30typedef struct binding_entry_s *binding_entry; 31 32/* The type of a routine repeatedly called by binding_table_foreach. */ 33typedef void (*bt_foreach_proc) (binding_entry, void *); 34 35struct binding_entry_s GTY(()) 36{ 37 binding_entry chain; 38 tree name; 39 tree type; 40}; 41 42/* These macros indicate the initial chains count for binding_table. */ 43#define SCOPE_DEFAULT_HT_SIZE (1 << 3) 44#define CLASS_SCOPE_HT_SIZE (1 << 3) 45#define NAMESPACE_ORDINARY_HT_SIZE (1 << 5) 46#define NAMESPACE_STD_HT_SIZE (1 << 8) 47#define GLOBAL_SCOPE_HT_SIZE (1 << 8) 48 49extern void binding_table_foreach (binding_table, bt_foreach_proc, void *); 50extern binding_entry binding_table_find (binding_table, tree); 51 52/* Datatype that represents binding established by a declaration between 53 a name and a C++ entity. */ 54typedef struct cxx_binding cxx_binding; 55 56/* The datatype used to implement C++ scope. */ 57typedef struct cp_binding_level cxx_scope; 58 59/* Nonzero if this binding is for a local scope, as opposed to a class 60 or namespace scope. */ 61#define LOCAL_BINDING_P(NODE) ((NODE)->is_local) 62 63/* True if NODE->value is from a base class of the class which is 64 currently being defined. */ 65#define INHERITED_VALUE_BINDING_P(NODE) ((NODE)->value_is_inherited) 66 67struct cxx_binding GTY(()) 68{ 69 /* Link to chain together various bindings for this name. */ 70 cxx_binding *previous; 71 /* The non-type entity this name is bound to. */ 72 tree value; 73 /* The type entity this name is bound to. */ 74 tree type; 75 /* The scope at which this binding was made. */ 76 cxx_scope *scope; 77 unsigned value_is_inherited : 1; 78 unsigned is_local : 1; 79}; 80 81/* Datatype used to temporarily save C++ bindings (for implicit 82 instantiations purposes and like). Implemented in decl.c. */ 83typedef struct cxx_saved_binding GTY(()) 84{ 85 /* The name of the current binding. */ 86 tree identifier; 87 /* The binding we're saving. */ 88 cxx_binding *binding; 89 tree real_type_value; 90} cxx_saved_binding; 91 92DEF_VEC_O(cxx_saved_binding); 93DEF_VEC_ALLOC_O(cxx_saved_binding,gc); 94 95extern tree identifier_type_value (tree); 96extern void set_identifier_type_value (tree, tree); 97extern void pop_binding (tree, tree); 98extern tree constructor_name (tree); 99extern bool constructor_name_p (tree, tree); 100 101/* The kinds of scopes we recognize. */ 102typedef enum scope_kind { 103 sk_block = 0, /* An ordinary block scope. This enumerator must 104 have the value zero because "cp_binding_level" 105 is initialized by using "memset" to set the 106 contents to zero, and the default scope kind 107 is "sk_block". */ 108 sk_cleanup, /* A scope for (pseudo-)scope for cleanup. It is 109 pseudo in that it is transparent to name lookup 110 activities. */ 111 sk_try, /* A try-block. */ 112 sk_catch, /* A catch-block. */ 113 sk_for, /* The scope of the variable declared in a 114 for-init-statement. */ 115 sk_function_parms, /* The scope containing function parameters. */ 116 sk_class, /* The scope containing the members of a class. */ 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_omp /* An OpenMP structured block. */ 125} scope_kind; 126 127/* The scope where the class/struct/union/enum tag applies. */ 128typedef enum tag_scope { 129 ts_current = 0, /* Current scope only. This is for the 130 class-key identifier; 131 case mentioned in [basic.lookup.elab]/2, 132 or the class/enum definition 133 class-key identifier { ... }; */ 134 ts_global = 1, /* All scopes. This is the 3.4.1 135 [basic.lookup.unqual] lookup mentioned 136 in [basic.lookup.elab]/2. */ 137 ts_within_enclosing_non_class = 2 /* Search within enclosing non-class 138 only, for friend class lookup 139 according to [namespace.memdef]/3 140 and [class.friend]/9. */ 141} tag_scope; 142 143typedef struct cp_class_binding GTY(()) 144{ 145 cxx_binding base; 146 /* The bound name. */ 147 tree identifier; 148} cp_class_binding; 149 150DEF_VEC_O(cp_class_binding); 151DEF_VEC_ALLOC_O(cp_class_binding,gc); 152 153/* For each binding contour we allocate a binding_level structure 154 which records the names defined in that contour. 155 Contours include: 156 0) the global one 157 1) one for each function definition, 158 where internal declarations of the parameters appear. 159 2) one for each compound statement, 160 to record its declarations. 161 162 The current meaning of a name can be found by searching the levels 163 from the current one out to the global one. 164 165 Off to the side, may be the class_binding_level. This exists only 166 to catch class-local declarations. It is otherwise nonexistent. 167 168 Also there may be binding levels that catch cleanups that must be 169 run when exceptions occur. Thus, to see whether a name is bound in 170 the current scope, it is not enough to look in the 171 CURRENT_BINDING_LEVEL. You should use lookup_name_current_level 172 instead. */ 173 174/* Note that the information in the `names' component of the global contour 175 is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers. */ 176 177struct cp_binding_level GTY(()) 178 { 179 /* A chain of _DECL nodes for all variables, constants, functions, 180 and typedef types. These are in the reverse of the order 181 supplied. There may be OVERLOADs on this list, too, but they 182 are wrapped in TREE_LISTs; the TREE_VALUE is the OVERLOAD. */ 183 tree names; 184 185 /* Count of elements in names chain. */ 186 size_t names_size; 187 188 /* A chain of NAMESPACE_DECL nodes. */ 189 tree namespaces; 190 191 /* An array of static functions and variables (for namespaces only) */ 192 VEC(tree,gc) *static_decls; 193 194 /* A chain of VTABLE_DECL nodes. */ 195 tree vtables; 196 197 /* A list of USING_DECL nodes. */ 198 tree usings; 199 200 /* A list of used namespaces. PURPOSE is the namespace, 201 VALUE the common ancestor with this binding_level's namespace. */ 202 tree using_directives; 203 204 /* For the binding level corresponding to a class, the entities 205 declared in the class or its base classes. */ 206 VEC(cp_class_binding,gc) *class_shadowed; 207 208 /* Similar to class_shadowed, but for IDENTIFIER_TYPE_VALUE, and 209 is used for all binding levels. The TREE_PURPOSE is the name of 210 the entity, the TREE_TYPE is the associated type. In addition 211 the TREE_VALUE is the IDENTIFIER_TYPE_VALUE before we entered 212 the class. */ 213 tree type_shadowed; 214 215 /* A TREE_LIST. Each TREE_VALUE is the LABEL_DECL for a local 216 label in this scope. The TREE_PURPOSE is the previous value of 217 the IDENTIFIER_LABEL VALUE. */ 218 tree shadowed_labels; 219 220 /* For each level (except not the global one), 221 a chain of BLOCK nodes for all the levels 222 that were entered and exited one level down. */ 223 tree blocks; 224 225 /* The entity (namespace, class, function) the scope of which this 226 binding contour corresponds to. Otherwise NULL. */ 227 tree this_entity; 228 229 /* The binding level which this one is contained in (inherits from). */ 230 struct cp_binding_level *level_chain; 231 232 /* List of VAR_DECLS saved from a previous for statement. 233 These would be dead in ISO-conforming code, but might 234 be referenced in ARM-era code. These are stored in a 235 TREE_LIST; the TREE_VALUE is the actual declaration. */ 236 tree dead_vars_from_for; 237 238 /* STATEMENT_LIST for statements in this binding contour. 239 Only used at present for SK_CLEANUP temporary bindings. */ 240 tree statement_list; 241 242 /* Binding depth at which this level began. */ 243 int binding_depth; 244 245 /* The kind of scope that this object represents. However, a 246 SK_TEMPLATE_SPEC scope is represented with KIND set to 247 SK_TEMPLATE_PARMS and EXPLICIT_SPEC_P set to true. */ 248 ENUM_BITFIELD (scope_kind) kind : 4; 249 250 /* True if this scope is an SK_TEMPLATE_SPEC scope. This field is 251 only valid if KIND == SK_TEMPLATE_PARMS. */ 252 BOOL_BITFIELD explicit_spec_p : 1; 253 254 /* true means make a BLOCK for this level regardless of all else. */ 255 unsigned keep : 1; 256 257 /* Nonzero if this level can safely have additional 258 cleanup-needing variables added to it. */ 259 unsigned more_cleanups_ok : 1; 260 unsigned have_cleanups : 1; 261 262 /* Nonzero if this level has associated visibility which we should pop 263 when leaving the scope. */ 264 unsigned has_visibility : 1; 265 266 /* 23 bits left to fill a 32-bit word. */ 267 }; 268 269/* The binding level currently in effect. */ 270 271#define current_binding_level \ 272 (*(cfun && cp_function_chain->bindings \ 273 ? &cp_function_chain->bindings \ 274 : &scope_chain->bindings)) 275 276/* The binding level of the current class, if any. */ 277 278#define class_binding_level scope_chain->class_bindings 279 280/* The tree node representing the global scope. */ 281extern GTY(()) tree global_namespace; 282extern GTY(()) tree global_scope_name; 283 284/* Indicates that there is a type value in some namespace, although 285 that is not necessarily in scope at the moment. */ 286 287extern GTY(()) tree global_type_node; 288 289/* True if SCOPE designates the global scope binding contour. */ 290#define global_scope_p(SCOPE) \ 291 ((SCOPE) == NAMESPACE_LEVEL (global_namespace)) 292 293extern cxx_scope *leave_scope (void); 294extern bool kept_level_p (void); 295extern int global_bindings_p (void); 296extern bool toplevel_bindings_p (void); 297extern bool namespace_bindings_p (void); 298extern bool template_parm_scope_p (void); 299extern scope_kind innermost_scope_kind (void); 300extern cxx_scope *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 (struct cp_binding_level *); 312 313extern void push_namespace (tree); 314extern void push_namespace_with_attribs (tree, tree); 315extern void pop_namespace (void); 316extern void push_nested_namespace (tree); 317extern void pop_nested_namespace (tree); 318extern void pushlevel_class (void); 319extern void poplevel_class (void); 320extern tree pushdecl_with_scope (tree, cxx_scope *, 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_function_nonclass (tree, tree, bool); 331extern void push_local_binding (tree, tree, int); 332extern bool pushdecl_class_level (tree); 333extern tree pushdecl_namespace_level (tree, bool); 334extern bool push_class_level_binding (tree, tree); 335extern tree getdecls (void); 336extern tree cp_namespace_decls (tree); 337extern void set_decl_namespace (tree, tree, bool); 338extern void push_decl_namespace (tree); 339extern void pop_decl_namespace (void); 340extern void do_namespace_alias (tree, tree); 341extern void do_toplevel_using_decl (tree, tree, tree); 342extern void do_local_using_decl (tree, tree, tree); 343extern tree do_class_using_decl (tree, tree); 344extern void do_using_directive (tree); 345extern tree lookup_arg_dependent (tree, tree, tree); 346extern bool is_associated_namespace (tree, tree); 347extern void parse_using_directive (tree, tree); 348extern tree innermost_non_namespace_value (tree); 349extern cxx_binding *outer_binding (tree, cxx_binding *, bool); 350extern void cp_emit_debug_info_for_using (tree, tree); 351 352/* Set *DECL to the (non-hidden) declaration for ID at global scope, 353 if present and return true; otherwise return false. */ 354 355static inline bool 356get_global_value_if_present (tree id, tree *decl) 357{ 358 tree global_value = namespace_binding (id, global_namespace); 359 if (global_value) 360 *decl = global_value; 361 return global_value != NULL; 362} 363 364/* True is the binding of IDENTIFIER at global scope names a type. */ 365 366static inline bool 367is_typename_at_global_scope (tree id) 368{ 369 tree global_value = namespace_binding (id, global_namespace); 370 371 return global_value && TREE_CODE (global_value) == TYPE_DECL; 372} 373 374#endif /* GCC_CP_NAME_LOOKUP_H */ 375