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@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 52 a name and a C++ entity. */ 53 typedef struct cxx_binding cxx_binding; 54 55 /* The datatype used to implement C++ scope. */ 56 typedef struct cp_binding_level cp_binding_level; 57 58 /* Nonzero if this binding is for a local scope, as opposed to a class 59 or namespace scope. */ 60 #define LOCAL_BINDING_P(NODE) ((NODE)->is_local) 61 62 /* True if NODE->value is from a base class of the class which is 63 currently being defined. */ 64 #define INHERITED_VALUE_BINDING_P(NODE) ((NODE)->value_is_inherited) 65 66 struct GTY(()) cxx_binding { 67 /* Link to chain together various bindings for this name. */ 68 cxx_binding *previous; 69 /* The non-type entity this name is bound to. */ 70 tree value; 71 /* The type entity this name is bound to. */ 72 tree type; 73 /* The scope at which this binding was made. */ 74 cp_binding_level *scope; 75 unsigned value_is_inherited : 1; 76 unsigned is_local : 1; 77 }; 78 79 /* Datatype used to temporarily save C++ bindings (for implicit 80 instantiations purposes and like). Implemented in decl.c. */ 81 typedef struct GTY(()) cxx_saved_binding { 82 /* The name of the current binding. */ 83 tree identifier; 84 /* The binding we're saving. */ 85 cxx_binding *binding; 86 tree real_type_value; 87 } cxx_saved_binding; 88 89 DEF_VEC_O(cxx_saved_binding); 90 DEF_VEC_ALLOC_O(cxx_saved_binding,gc); 91 92 extern tree identifier_type_value (tree); 93 extern void set_identifier_type_value (tree, tree); 94 extern void pop_binding (tree, tree); 95 extern tree constructor_name (tree); 96 extern bool constructor_name_p (tree, tree); 97 98 /* The kinds of scopes we recognize. */ 99 typedef enum scope_kind { 100 sk_block = 0, /* An ordinary block scope. This enumerator must 101 have the value zero because "cp_binding_level" 102 is initialized by using "memset" to set the 103 contents to zero, and the default scope kind 104 is "sk_block". */ 105 sk_cleanup, /* A scope for (pseudo-)scope for cleanup. It is 106 pseudo in that it is transparent to name lookup 107 activities. */ 108 sk_try, /* A try-block. */ 109 sk_catch, /* A catch-block. */ 110 sk_for, /* The scope of the variable declared in a 111 for-init-statement. */ 112 sk_cond, /* The scope of the variable declared in the condition 113 of an if or switch statement. */ 114 sk_function_parms, /* The scope containing function parameters. */ 115 sk_class, /* The scope containing the members of a class. */ 116 sk_scoped_enum, /* The scope containing the enumertors of a C++0x 117 scoped enumeration. */ 118 sk_namespace, /* The scope containing the members of a 119 namespace, including the global scope. */ 120 sk_template_parms, /* A scope for template parameters. */ 121 sk_template_spec, /* Like sk_template_parms, but for an explicit 122 specialization. Since, by definition, an 123 explicit specialization is introduced by 124 "template <>", this scope is always empty. */ 125 sk_omp /* An OpenMP structured block. */ 126 } scope_kind; 127 128 /* The scope where the class/struct/union/enum tag applies. */ 129 typedef enum 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 } tag_scope; 143 144 typedef struct GTY(()) cp_class_binding { 145 cxx_binding *base; 146 /* The bound name. */ 147 tree identifier; 148 } cp_class_binding; 149 150 DEF_VEC_O(cp_class_binding); 151 DEF_VEC_ALLOC_O(cp_class_binding,gc); 152 153 typedef struct GTY(()) cp_label_binding { 154 /* The bound LABEL_DECL. */ 155 tree label; 156 /* The previous IDENTIFIER_LABEL_VALUE. */ 157 tree prev_value; 158 } cp_label_binding; 159 160 DEF_VEC_O(cp_label_binding); 161 DEF_VEC_ALLOC_O(cp_label_binding,gc); 162 163 /* For each binding contour we allocate a binding_level structure 164 which records the names defined in that contour. 165 Contours include: 166 0) the global one 167 1) one for each function definition, 168 where internal declarations of the parameters appear. 169 2) one for each compound statement, 170 to record its declarations. 171 172 The current meaning of a name can be found by searching the levels 173 from the current one out to the global one. 174 175 Off to the side, may be the class_binding_level. This exists only 176 to catch class-local declarations. It is otherwise nonexistent. 177 178 Also there may be binding levels that catch cleanups that must be 179 run when exceptions occur. Thus, to see whether a name is bound in 180 the current scope, it is not enough to look in the 181 CURRENT_BINDING_LEVEL. You should use lookup_name_current_level 182 instead. */ 183 184 /* Note that the information in the `names' component of the global contour 185 is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers. */ 186 187 struct GTY(()) cp_binding_level { 188 /* A chain of _DECL nodes for all variables, constants, functions, 189 and typedef types. These are in the reverse of the order 190 supplied. There may be OVERLOADs on this list, too, but they 191 are wrapped in TREE_LISTs; the TREE_VALUE is the OVERLOAD. */ 192 tree names; 193 194 /* A chain of NAMESPACE_DECL nodes. */ 195 tree namespaces; 196 197 /* An array of static functions and variables (for namespaces only) */ 198 VEC(tree,gc) *static_decls; 199 200 /* A list of USING_DECL nodes. */ 201 tree usings; 202 203 /* A list of used namespaces. PURPOSE is the namespace, 204 VALUE the common ancestor with this binding_level's namespace. */ 205 tree using_directives; 206 207 /* For the binding level corresponding to a class, the entities 208 declared in the class or its base classes. */ 209 VEC(cp_class_binding,gc) *class_shadowed; 210 211 /* Similar to class_shadowed, but for IDENTIFIER_TYPE_VALUE, and 212 is used for all binding levels. The TREE_PURPOSE is the name of 213 the entity, the TREE_TYPE is the associated type. In addition 214 the TREE_VALUE is the IDENTIFIER_TYPE_VALUE before we entered 215 the class. */ 216 tree type_shadowed; 217 218 /* Similar to class_shadowed, but for IDENTIFIER_LABEL_VALUE, and 219 used for all binding levels. */ 220 VEC(cp_label_binding,gc) *shadowed_labels; 221 222 /* For each level (except not the global one), 223 a chain of BLOCK nodes for all the levels 224 that were entered and exited one level down. */ 225 tree blocks; 226 227 /* The entity (namespace, class, function) the scope of which this 228 binding contour corresponds to. Otherwise NULL. */ 229 tree this_entity; 230 231 /* The binding level which this one is contained in (inherits from). */ 232 cp_binding_level *level_chain; 233 234 /* List of VAR_DECLS saved from a previous for statement. 235 These would be dead in ISO-conforming code, but might 236 be referenced in ARM-era code. */ 237 VEC(tree,gc) *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 && 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 cp_binding_level *leave_scope (void); 291 extern bool kept_level_p (void); 292 extern bool global_bindings_p (void); 293 extern bool toplevel_bindings_p (void); 294 extern bool namespace_bindings_p (void); 295 extern bool local_bindings_p (void); 296 extern bool template_parm_scope_p (void); 297 extern scope_kind innermost_scope_kind (void); 298 extern cp_binding_level *begin_scope (scope_kind, tree); 299 extern void print_binding_stack (void); 300 extern void push_to_top_level (void); 301 extern void pop_from_top_level (void); 302 extern void pop_everything (void); 303 extern void keep_next_level (bool); 304 extern bool is_ancestor (tree, tree); 305 extern tree push_scope (tree); 306 extern void pop_scope (tree); 307 extern tree push_inner_scope (tree); 308 extern void pop_inner_scope (tree, tree); 309 extern void push_binding_level (cp_binding_level *); 310 311 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, cp_binding_level *, 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 bool is_local_extern (tree); 330 extern tree lookup_function_nonclass (tree, VEC(tree,gc) *, bool); 331 extern void push_local_binding (tree, tree, int); 332 extern bool pushdecl_class_level (tree); 333 extern tree pushdecl_namespace_level (tree, bool); 334 extern bool push_class_level_binding (tree, tree); 335 extern tree getdecls (void); 336 extern int function_parm_depth (void); 337 extern tree cp_namespace_decls (tree); 338 extern void set_decl_namespace (tree, tree, bool); 339 extern void push_decl_namespace (tree); 340 extern void pop_decl_namespace (void); 341 extern void do_namespace_alias (tree, tree); 342 extern void do_toplevel_using_decl (tree, tree, tree); 343 extern void do_local_using_decl (tree, tree, tree); 344 extern tree do_class_using_decl (tree, tree); 345 extern void do_using_directive (tree); 346 extern tree lookup_arg_dependent (tree, tree, VEC(tree,gc) *, bool); 347 extern bool is_associated_namespace (tree, tree); 348 extern void parse_using_directive (tree, tree); 349 extern tree innermost_non_namespace_value (tree); 350 extern cxx_binding *outer_binding (tree, cxx_binding *, bool); 351 extern void cp_emit_debug_info_for_using (tree, tree); 352 353 /* Set *DECL to the (non-hidden) declaration for ID at global scope, 354 if present and return true; otherwise return false. */ 355 356 static inline bool 357 get_global_value_if_present (tree id, tree *decl) 358 { 359 tree global_value = namespace_binding (id, global_namespace); 360 if (global_value) 361 *decl = global_value; 362 return global_value != NULL; 363 } 364 365 /* True is the binding of IDENTIFIER at global scope names a type. */ 366 367 static inline bool 368 is_typename_at_global_scope (tree id) 369 { 370 tree global_value = namespace_binding (id, global_namespace); 371 372 return global_value && TREE_CODE (global_value) == TYPE_DECL; 373 } 374 375 #endif /* GCC_CP_NAME_LOOKUP_H */ 376