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 (at) integrable-solutions.net> 4 5 This file is part of GCC. 6 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) 10 any later version. 11 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. 16 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/>. */ 20 21 #ifndef GCC_CP_NAME_LOOKUP_H 22 #define GCC_CP_NAME_LOOKUP_H 23 24 #include "c-common.h" 25 26 /* The type of dictionary used to map names to types declared at 27 a given scope. */ 28 typedef struct binding_table_s *binding_table; 29 typedef struct binding_entry_s *binding_entry; 30 31 /* The type of a routine repeatedly called by binding_table_foreach. */ 32 typedef void (*bt_foreach_proc) (binding_entry, void *); 33 34 struct binding_entry_s GTY(()) 35 { 36 binding_entry chain; 37 tree name; 38 tree type; 39 }; 40 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) 47 48 extern void binding_table_foreach (binding_table, bt_foreach_proc, void *); 49 extern binding_entry binding_table_find (binding_table, tree); 50 51 /* Datatype that represents binding established by a declaration between 53 a name and a C++ entity. */ 54 typedef struct cxx_binding cxx_binding; 55 56 /* The datatype used to implement C++ scope. */ 57 typedef 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 67 struct 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. */ 83 typedef 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 92 DEF_VEC_O(cxx_saved_binding); 93 DEF_VEC_ALLOC_O(cxx_saved_binding,gc); 94 95 extern tree identifier_type_value (tree); 96 extern void set_identifier_type_value (tree, tree); 97 extern void pop_binding (tree, tree); 98 extern void pop_global_binding (tree, cxx_binding*); 99 extern tree constructor_name (tree); 100 extern bool constructor_name_p (tree, tree); 101 102 /* The kinds of scopes we recognize. */ 104 typedef enum scope_kind { 105 sk_block = 0, /* An ordinary block scope. This enumerator must 106 have the value zero because "cp_binding_level" 107 is initialized by using "memset" to set the 108 contents to zero, and the default scope kind 109 is "sk_block". */ 110 sk_cleanup, /* A scope for (pseudo-)scope for cleanup. It is 111 pseudo in that it is transparent to name lookup 112 activities. */ 113 sk_try, /* A try-block. */ 114 sk_catch, /* A catch-block. */ 115 sk_for, /* The scope of the variable declared in a 116 for-init-statement. */ 117 sk_function_parms, /* The scope containing function parameters. */ 118 sk_class, /* The scope containing the members of a class. */ 119 sk_scoped_enum, /* The scope containing the enumertors of a C++0x 120 scoped enumeration. */ 121 sk_namespace, /* The scope containing the members of a 122 namespace, including the global scope. */ 123 sk_template_parms, /* A scope for template parameters. */ 124 sk_template_spec, /* Like sk_template_parms, but for an explicit 125 specialization. Since, by definition, an 126 explicit specialization is introduced by 127 "template <>", this scope is always empty. */ 128 sk_omp /* An OpenMP structured block. */ 129 } scope_kind; 130 131 /* The scope where the class/struct/union/enum tag applies. */ 132 typedef enum tag_scope { 133 ts_current = 0, /* Current scope only. This is for the 134 class-key identifier; 135 case mentioned in [basic.lookup.elab]/2, 136 or the class/enum definition 137 class-key identifier { ... }; */ 138 ts_global = 1, /* All scopes. This is the 3.4.1 139 [basic.lookup.unqual] lookup mentioned 140 in [basic.lookup.elab]/2. */ 141 ts_within_enclosing_non_class = 2 /* Search within enclosing non-class 142 only, for friend class lookup 143 according to [namespace.memdef]/3 144 and [class.friend]/9. */ 145 } tag_scope; 146 147 typedef struct cp_class_binding GTY(()) 148 { 149 cxx_binding base; 150 /* The bound name. */ 151 tree identifier; 152 } cp_class_binding; 153 154 DEF_VEC_O(cp_class_binding); 155 DEF_VEC_ALLOC_O(cp_class_binding,gc); 156 157 /* For each binding contour we allocate a binding_level structure 158 which records the names defined in that contour. 159 Contours include: 160 0) the global one 161 1) one for each function definition, 162 where internal declarations of the parameters appear. 163 2) one for each compound statement, 164 to record its declarations. 165 166 The current meaning of a name can be found by searching the levels 167 from the current one out to the global one. 168 169 Off to the side, may be the class_binding_level. This exists only 170 to catch class-local declarations. It is otherwise nonexistent. 171 172 Also there may be binding levels that catch cleanups that must be 173 run when exceptions occur. Thus, to see whether a name is bound in 174 the current scope, it is not enough to look in the 175 CURRENT_BINDING_LEVEL. You should use lookup_name_current_level 176 instead. */ 177 178 /* Note that the information in the `names' component of the global contour 179 is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers. */ 180 181 struct cp_binding_level GTY(()) 182 { 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 /* Count of elements in names chain. */ 190 size_t names_size; 191 192 /* A chain of NAMESPACE_DECL nodes. */ 193 tree namespaces; 194 195 /* An array of static functions and variables (for namespaces only) */ 196 VEC(tree,gc) *static_decls; 197 198 /* A list of USING_DECL nodes. */ 199 tree usings; 200 201 /* A list of used namespaces. PURPOSE is the namespace, 202 VALUE the common ancestor with this binding_level's namespace. */ 203 tree using_directives; 204 205 /* For the binding level corresponding to a class, the entities 206 declared in the class or its base classes. */ 207 VEC(cp_class_binding,gc) *class_shadowed; 208 209 /* Similar to class_shadowed, but for IDENTIFIER_TYPE_VALUE, and 210 is used for all binding levels. The TREE_PURPOSE is the name of 211 the entity, the TREE_TYPE is the associated type. In addition 212 the TREE_VALUE is the IDENTIFIER_TYPE_VALUE before we entered 213 the class. */ 214 tree type_shadowed; 215 216 /* A TREE_LIST. Each TREE_VALUE is the LABEL_DECL for a local 217 label in this scope. The TREE_PURPOSE is the previous value of 218 the IDENTIFIER_LABEL VALUE. */ 219 tree shadowed_labels; 220 221 /* For each level (except not the global one), 222 a chain of BLOCK nodes for all the levels 223 that were entered and exited one level down. */ 224 tree blocks; 225 226 /* The entity (namespace, class, function) the scope of which this 227 binding contour corresponds to. Otherwise NULL. */ 228 tree this_entity; 229 230 /* The binding level which this one is contained in (inherits from). */ 231 struct cp_binding_level *level_chain; 232 233 /* List of VAR_DECLS saved from a previous for statement. 234 These would be dead in ISO-conforming code, but might 235 be referenced in ARM-era code. These are stored in a 236 TREE_LIST; the TREE_VALUE is the actual declaration. */ 237 tree dead_vars_from_for; 238 239 /* STATEMENT_LIST for statements in this binding contour. 240 Only used at present for SK_CLEANUP temporary bindings. */ 241 tree statement_list; 242 243 /* Binding depth at which this level began. */ 244 int binding_depth; 245 246 /* The kind of scope that this object represents. However, a 247 SK_TEMPLATE_SPEC scope is represented with KIND set to 248 SK_TEMPLATE_PARMS and EXPLICIT_SPEC_P set to true. */ 249 ENUM_BITFIELD (scope_kind) kind : 4; 250 251 /* True if this scope is an SK_TEMPLATE_SPEC scope. This field is 252 only valid if KIND == SK_TEMPLATE_PARMS. */ 253 BOOL_BITFIELD explicit_spec_p : 1; 254 255 /* true means make a BLOCK for this level regardless of all else. */ 256 unsigned keep : 1; 257 258 /* Nonzero if this level can safely have additional 259 cleanup-needing variables added to it. */ 260 unsigned more_cleanups_ok : 1; 261 unsigned have_cleanups : 1; 262 263 /* 24 bits left to fill a 32-bit word. */ 264 }; 265 266 /* The binding level currently in effect. */ 267 268 #define current_binding_level \ 269 (*(cfun && cp_function_chain->bindings \ 270 ? &cp_function_chain->bindings \ 271 : &scope_chain->bindings)) 272 273 /* The binding level of the current class, if any. */ 274 275 #define class_binding_level scope_chain->class_bindings 276 277 /* The tree node representing the global scope. */ 278 extern GTY(()) tree global_namespace; 279 extern GTY(()) tree global_scope_name; 280 281 /* Indicates that there is a type value in some namespace, although 282 that is not necessarily in scope at the moment. */ 283 284 extern GTY(()) tree global_type_node; 285 286 /* True if SCOPE designates the global scope binding contour. */ 287 #define global_scope_p(SCOPE) \ 288 ((SCOPE) == NAMESPACE_LEVEL (global_namespace)) 289 290 extern cxx_scope *leave_scope (void); 291 extern bool kept_level_p (void); 292 extern int global_bindings_p (void); 293 extern bool toplevel_bindings_p (void); 294 extern bool namespace_bindings_p (void); 295 extern bool template_parm_scope_p (void); 296 extern scope_kind innermost_scope_kind (void); 297 extern cxx_scope *begin_scope (scope_kind, tree); 298 extern void print_binding_stack (void); 299 extern void push_to_top_level (void); 300 extern void pop_from_top_level (void); 301 extern void pop_everything (void); 302 extern void keep_next_level (bool); 303 extern bool is_ancestor (tree, tree); 304 extern tree push_scope (tree); 305 extern void pop_scope (tree); 306 extern tree push_inner_scope (tree); 307 extern void pop_inner_scope (tree, tree); 308 extern void push_binding_level (struct cp_binding_level *); 309 310 extern void push_namespace (tree); 312 extern void pop_namespace (void); 313 extern void push_nested_namespace (tree); 314 extern void pop_nested_namespace (tree); 315 extern bool handle_namespace_attrs (tree, tree); 316 extern void pushlevel_class (void); 317 extern void poplevel_class (void); 318 extern tree pushdecl_with_scope (tree, cxx_scope *, bool); 319 extern tree lookup_name_prefer_type (tree, int); 320 extern tree lookup_name_real (tree, int, int, bool, int, int); 321 extern tree lookup_type_scope (tree, tag_scope); 322 extern tree namespace_binding (tree, tree); 323 extern void set_namespace_binding (tree, tree, tree); 324 extern bool hidden_name_p (tree); 325 extern tree remove_hidden_names (tree); 326 extern tree lookup_qualified_name (tree, tree, bool, bool); 327 extern tree lookup_name_nonclass (tree); 328 extern tree lookup_name_innermost_nonclass_level (tree); 329 extern tree lookup_function_nonclass (tree, tree, bool); 330 extern void push_local_binding (tree, tree, int); 331 extern bool pushdecl_class_level (tree); 332 extern tree pushdecl_namespace_level (tree, bool); 333 extern bool push_class_level_binding (tree, tree); 334 extern tree getdecls (void); 335 extern tree cp_namespace_decls (tree); 336 extern void set_decl_namespace (tree, tree, bool); 337 extern void push_decl_namespace (tree); 338 extern void pop_decl_namespace (void); 339 extern void do_namespace_alias (tree, tree); 340 extern void do_toplevel_using_decl (tree, tree, tree); 341 extern void do_local_using_decl (tree, tree, tree); 342 extern tree do_class_using_decl (tree, tree); 343 extern void do_using_directive (tree); 344 extern tree lookup_arg_dependent (tree, tree, tree); 345 extern bool is_associated_namespace (tree, tree); 346 extern void parse_using_directive (tree, tree); 347 extern tree innermost_non_namespace_value (tree); 348 extern cxx_binding *outer_binding (tree, cxx_binding *, bool); 349 extern void cp_emit_debug_info_for_using (tree, tree); 350 351 /* Set *DECL to the (non-hidden) declaration for ID at global scope, 352 if present and return true; otherwise return false. */ 353 354 static inline bool 355 get_global_value_if_present (tree id, tree *decl) 356 { 357 tree global_value = namespace_binding (id, global_namespace); 358 if (global_value) 359 *decl = global_value; 360 return global_value != NULL; 361 } 362 363 /* True is the binding of IDENTIFIER at global scope names a type. */ 364 365 static inline bool 366 is_typename_at_global_scope (tree id) 367 { 368 tree global_value = namespace_binding (id, global_namespace); 369 370 return global_value && TREE_CODE (global_value) == TYPE_DECL; 371 } 372 373 #endif /* GCC_CP_NAME_LOOKUP_H */ 374
