1 /* Declarations for C++ name lookup routines. 2 Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009, 2010 3 Free Software Foundation, Inc. 4 Contributed by Gabriel Dos Reis <gdr (at) integrable-solutions.net> 5 6 This file is part of GCC. 7 8 GCC is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 3, or (at your option) 11 any later version. 12 13 GCC is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with GCC; see the file COPYING3. If not see 20 <http://www.gnu.org/licenses/>. */ 21 22 #ifndef GCC_CP_NAME_LOOKUP_H 23 #define GCC_CP_NAME_LOOKUP_H 24 25 #include "c-family/c-common.h" 26 27 /* The type of dictionary used to map names to types declared at 28 a given scope. */ 29 typedef struct binding_table_s *binding_table; 30 typedef struct binding_entry_s *binding_entry; 31 32 /* The type of a routine repeatedly called by binding_table_foreach. */ 33 typedef void (*bt_foreach_proc) (binding_entry, void *); 34 35 struct GTY(()) binding_entry_s { 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 GTY(()) cxx_binding { 68 /* Link to chain together various bindings for this name. */ 69 cxx_binding *previous; 70 /* The non-type entity this name is bound to. */ 71 tree value; 72 /* The type entity this name is bound to. */ 73 tree type; 74 /* The scope at which this binding was made. */ 75 cxx_scope *scope; 76 unsigned value_is_inherited : 1; 77 unsigned is_local : 1; 78 }; 79 80 /* Datatype used to temporarily save C++ bindings (for implicit 81 instantiations purposes and like). Implemented in decl.c. */ 82 typedef struct GTY(()) cxx_saved_binding { 83 /* The name of the current binding. */ 84 tree identifier; 85 /* The binding we're saving. */ 86 cxx_binding *binding; 87 tree real_type_value; 88 } cxx_saved_binding; 89 90 DEF_VEC_O(cxx_saved_binding); 91 DEF_VEC_ALLOC_O(cxx_saved_binding,gc); 92 93 extern tree identifier_type_value (tree); 94 extern void set_identifier_type_value (tree, tree); 95 extern void pop_binding (tree, tree); 96 extern void pop_global_binding (tree, cxx_binding*); 97 extern tree constructor_name (tree); 98 extern bool constructor_name_p (tree, tree); 99 100 /* The kinds of scopes we recognize. */ 102 typedef 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_scoped_enum, /* The scope containing the enumertors of a C++0x 118 scoped enumeration. */ 119 sk_namespace, /* The scope containing the members of a 120 namespace, including the global scope. */ 121 sk_template_parms, /* A scope for template parameters. */ 122 sk_template_spec, /* Like sk_template_parms, but for an explicit 123 specialization. Since, by definition, an 124 explicit specialization is introduced by 125 "template <>", this scope is always empty. */ 126 sk_omp /* An OpenMP structured block. */ 127 } scope_kind; 128 129 /* The scope where the class/struct/union/enum tag applies. */ 130 typedef enum tag_scope { 131 ts_current = 0, /* Current scope only. This is for the 132 class-key identifier; 133 case mentioned in [basic.lookup.elab]/2, 134 or the class/enum definition 135 class-key identifier { ... }; */ 136 ts_global = 1, /* All scopes. This is the 3.4.1 137 [basic.lookup.unqual] lookup mentioned 138 in [basic.lookup.elab]/2. */ 139 ts_within_enclosing_non_class = 2 /* Search within enclosing non-class 140 only, for friend class lookup 141 according to [namespace.memdef]/3 142 and [class.friend]/9. */ 143 } tag_scope; 144 145 typedef struct GTY(()) cp_class_binding { 146 cxx_binding base; 147 /* The bound name. */ 148 tree identifier; 149 } cp_class_binding; 150 151 DEF_VEC_O(cp_class_binding); 152 DEF_VEC_ALLOC_O(cp_class_binding,gc); 153 154 typedef struct GTY(()) cp_label_binding { 155 /* The bound LABEL_DECL. */ 156 tree label; 157 /* The previous IDENTIFIER_LABEL_VALUE. */ 158 tree prev_value; 159 } cp_label_binding; 160 161 DEF_VEC_O(cp_label_binding); 162 DEF_VEC_ALLOC_O(cp_label_binding,gc); 163 164 /* For each binding contour we allocate a binding_level structure 165 which records the names defined in that contour. 166 Contours include: 167 0) the global one 168 1) one for each function definition, 169 where internal declarations of the parameters appear. 170 2) one for each compound statement, 171 to record its declarations. 172 173 The current meaning of a name can be found by searching the levels 174 from the current one out to the global one. 175 176 Off to the side, may be the class_binding_level. This exists only 177 to catch class-local declarations. It is otherwise nonexistent. 178 179 Also there may be binding levels that catch cleanups that must be 180 run when exceptions occur. Thus, to see whether a name is bound in 181 the current scope, it is not enough to look in the 182 CURRENT_BINDING_LEVEL. You should use lookup_name_current_level 183 instead. */ 184 185 /* Note that the information in the `names' component of the global contour 186 is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers. */ 187 188 struct GTY(()) cp_binding_level { 189 /* A chain of _DECL nodes for all variables, constants, functions, 190 and typedef types. These are in the reverse of the order 191 supplied. There may be OVERLOADs on this list, too, but they 192 are wrapped in TREE_LISTs; the TREE_VALUE is the OVERLOAD. */ 193 tree names; 194 195 /* Count of elements in names chain. */ 196 size_t names_size; 197 198 /* A chain of NAMESPACE_DECL nodes. */ 199 tree namespaces; 200 201 /* An array of static functions and variables (for namespaces only) */ 202 VEC(tree,gc) *static_decls; 203 204 /* A list of USING_DECL nodes. */ 205 tree usings; 206 207 /* A list of used namespaces. PURPOSE is the namespace, 208 VALUE the common ancestor with this binding_level's namespace. */ 209 tree using_directives; 210 211 /* For the binding level corresponding to a class, the entities 212 declared in the class or its base classes. */ 213 VEC(cp_class_binding,gc) *class_shadowed; 214 215 /* Similar to class_shadowed, but for IDENTIFIER_TYPE_VALUE, and 216 is used for all binding levels. The TREE_PURPOSE is the name of 217 the entity, the TREE_TYPE is the associated type. In addition 218 the TREE_VALUE is the IDENTIFIER_TYPE_VALUE before we entered 219 the class. */ 220 tree type_shadowed; 221 222 /* Similar to class_shadowed, but for IDENTIFIER_LABEL_VALUE, and 223 used for all binding levels. */ 224 VEC(cp_label_binding,gc) *shadowed_labels; 225 226 /* For each level (except not the global one), 227 a chain of BLOCK nodes for all the levels 228 that were entered and exited one level down. */ 229 tree blocks; 230 231 /* The entity (namespace, class, function) the scope of which this 232 binding contour corresponds to. Otherwise NULL. */ 233 tree this_entity; 234 235 /* The binding level which this one is contained in (inherits from). */ 236 struct cp_binding_level *level_chain; 237 238 /* List of VAR_DECLS saved from a previous for statement. 239 These would be dead in ISO-conforming code, but might 240 be referenced in ARM-era code. */ 241 VEC(tree,gc) *dead_vars_from_for; 242 243 /* STATEMENT_LIST for statements in this binding contour. 244 Only used at present for SK_CLEANUP temporary bindings. */ 245 tree statement_list; 246 247 /* Binding depth at which this level began. */ 248 int binding_depth; 249 250 /* The kind of scope that this object represents. However, a 251 SK_TEMPLATE_SPEC scope is represented with KIND set to 252 SK_TEMPLATE_PARMS and EXPLICIT_SPEC_P set to true. */ 253 ENUM_BITFIELD (scope_kind) kind : 4; 254 255 /* True if this scope is an SK_TEMPLATE_SPEC scope. This field is 256 only valid if KIND == SK_TEMPLATE_PARMS. */ 257 BOOL_BITFIELD explicit_spec_p : 1; 258 259 /* true means make a BLOCK for this level regardless of all else. */ 260 unsigned keep : 1; 261 262 /* Nonzero if this level can safely have additional 263 cleanup-needing variables added to it. */ 264 unsigned more_cleanups_ok : 1; 265 unsigned have_cleanups : 1; 266 267 /* 24 bits left to fill a 32-bit word. */ 268 }; 269 270 /* The binding level currently in effect. */ 271 272 #define current_binding_level \ 273 (*(cfun && cp_function_chain && cp_function_chain->bindings \ 274 ? &cp_function_chain->bindings \ 275 : &scope_chain->bindings)) 276 277 /* The binding level of the current class, if any. */ 278 279 #define class_binding_level scope_chain->class_bindings 280 281 /* The tree node representing the global scope. */ 282 extern GTY(()) tree global_namespace; 283 extern GTY(()) tree global_scope_name; 284 285 /* Indicates that there is a type value in some namespace, although 286 that is not necessarily in scope at the moment. */ 287 288 extern GTY(()) tree global_type_node; 289 290 /* True if SCOPE designates the global scope binding contour. */ 291 #define global_scope_p(SCOPE) \ 292 ((SCOPE) == NAMESPACE_LEVEL (global_namespace)) 293 294 extern cxx_scope *leave_scope (void); 295 extern bool kept_level_p (void); 296 extern int global_bindings_p (void); 297 extern bool toplevel_bindings_p (void); 298 extern bool namespace_bindings_p (void); 299 extern bool template_parm_scope_p (void); 300 extern scope_kind innermost_scope_kind (void); 301 extern cxx_scope *begin_scope (scope_kind, tree); 302 extern void print_binding_stack (void); 303 extern void push_to_top_level (void); 304 extern void pop_from_top_level (void); 305 extern void pop_everything (void); 306 extern void keep_next_level (bool); 307 extern bool is_ancestor (tree, tree); 308 extern tree push_scope (tree); 309 extern void pop_scope (tree); 310 extern tree push_inner_scope (tree); 311 extern void pop_inner_scope (tree, tree); 312 extern void push_binding_level (struct cp_binding_level *); 313 314 extern void push_namespace (tree); 316 extern void pop_namespace (void); 317 extern void push_nested_namespace (tree); 318 extern void pop_nested_namespace (tree); 319 extern bool handle_namespace_attrs (tree, tree); 320 extern void pushlevel_class (void); 321 extern void poplevel_class (void); 322 extern tree pushdecl_with_scope (tree, cxx_scope *, bool); 323 extern tree lookup_name_prefer_type (tree, int); 324 extern tree lookup_name_real (tree, int, int, bool, int, int); 325 extern tree lookup_type_scope (tree, tag_scope); 326 extern tree namespace_binding (tree, tree); 327 extern void set_namespace_binding (tree, tree, tree); 328 extern bool hidden_name_p (tree); 329 extern tree remove_hidden_names (tree); 330 extern tree lookup_qualified_name (tree, tree, bool, bool); 331 extern tree lookup_name_nonclass (tree); 332 extern tree lookup_name_innermost_nonclass_level (tree); 333 extern tree lookup_name_in_func_params (tree, tree); 334 extern bool is_local_extern (tree); 335 extern tree lookup_function_nonclass (tree, VEC(tree,gc) *, bool); 336 extern void push_local_binding (tree, tree, int); 337 extern bool pushdecl_class_level (tree); 338 extern tree pushdecl_namespace_level (tree, bool); 339 extern bool push_class_level_binding (tree, tree); 340 extern tree getdecls (void); 341 extern int function_parm_depth (void); 342 extern tree cp_namespace_decls (tree); 343 extern void set_decl_namespace (tree, tree, bool); 344 extern void push_decl_namespace (tree); 345 extern void pop_decl_namespace (void); 346 extern void do_namespace_alias (tree, tree); 347 extern void do_toplevel_using_decl (tree, tree, tree); 348 extern void do_local_using_decl (tree, tree, tree); 349 extern tree do_class_using_decl (tree, tree); 350 extern void do_using_directive (tree); 351 extern tree lookup_arg_dependent (tree, tree, VEC(tree,gc) *, bool); 352 extern bool is_associated_namespace (tree, tree); 353 extern void parse_using_directive (tree, tree); 354 extern tree innermost_non_namespace_value (tree); 355 extern cxx_binding *outer_binding (tree, cxx_binding *, bool); 356 extern void cp_emit_debug_info_for_using (tree, tree); 357 358 /* Set *DECL to the (non-hidden) declaration for ID at global scope, 359 if present and return true; otherwise return false. */ 360 361 static inline bool 362 get_global_value_if_present (tree id, tree *decl) 363 { 364 tree global_value = namespace_binding (id, global_namespace); 365 if (global_value) 366 *decl = global_value; 367 return global_value != NULL; 368 } 369 370 /* True is the binding of IDENTIFIER at global scope names a type. */ 371 372 static inline bool 373 is_typename_at_global_scope (tree id) 374 { 375 tree global_value = namespace_binding (id, global_namespace); 376 377 return global_value && TREE_CODE (global_value) == TYPE_DECL; 378 } 379 380 #endif /* GCC_CP_NAME_LOOKUP_H */ 381
