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 peusdo 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} 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} tag_scope; 141 142typedef struct cp_class_binding GTY(()) 143{ 144 cxx_binding base; 145 /* The bound name. */ 146 tree identifier; 147} cp_class_binding; 148 149DEF_VEC_O(cp_class_binding); 150DEF_VEC_ALLOC_O(cp_class_binding,gc); 151 152/* For each binding contour we allocate a binding_level structure 153 which records the names defined in that contour. 154 Contours include: 155 0) the global one 156 1) one for each function definition, 157 where internal declarations of the parameters appear. 158 2) one for each compound statement, 159 to record its declarations. 160 161 The current meaning of a name can be found by searching the levels 162 from the current one out to the global one. 163 164 Off to the side, may be the class_binding_level. This exists only 165 to catch class-local declarations. It is otherwise nonexistent. 166 167 Also there may be binding levels that catch cleanups that must be 168 run when exceptions occur. Thus, to see whether a name is bound in 169 the current scope, it is not enough to look in the 170 CURRENT_BINDING_LEVEL. You should use lookup_name_current_level 171 instead. */ 172 173/* Note that the information in the `names' component of the global contour 174 is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers. */ 175 176struct cp_binding_level GTY(()) 177 { 178 /* A chain of _DECL nodes for all variables, constants, functions, 179 and typedef types. These are in the reverse of the order 180 supplied. There may be OVERLOADs on this list, too, but they 181 are wrapped in TREE_LISTs; the TREE_VALUE is the OVERLOAD. */ 182 tree names; 183 184 /* Count of elements in names chain. */ 185 size_t names_size; 186 187 /* A chain of NAMESPACE_DECL nodes. */ 188 tree namespaces; 189 190 /* An array of static functions and variables (for namespaces only) */ 191 VEC(tree,gc) *static_decls; 192 193 /* A chain of VTABLE_DECL nodes. */ 194 tree vtables; 195 196 /* A list of USING_DECL nodes. */ 197 tree usings; 198 199 /* A list of used namespaces. PURPOSE is the namespace, 200 VALUE the common ancestor with this binding_level's namespace. */ 201 tree using_directives; 202 203 /* For the binding level corresponding to a class, the entities 204 declared in the class or its base classes. */ 205 VEC(cp_class_binding,gc) *class_shadowed; 206 207 /* Similar to class_shadowed, but for IDENTIFIER_TYPE_VALUE, and 208 is used for all binding levels. The TREE_PURPOSE is the name of 209 the entity, the TREE_TYPE is the associated type. In addition 210 the TREE_VALUE is the IDENTIFIER_TYPE_VALUE before we entered 211 the class. */ 212 tree type_shadowed; 213 214 /* A TREE_LIST. Each TREE_VALUE is the LABEL_DECL for a local 215 label in this scope. The TREE_PURPOSE is the previous value of 216 the IDENTIFIER_LABEL VALUE. */ 217 tree shadowed_labels; 218 219 /* For each level (except not the global one), 220 a chain of BLOCK nodes for all the levels 221 that were entered and exited one level down. */ 222 tree blocks; 223 224 /* The entity (namespace, class, function) the scope of which this 225 binding contour corresponds to. Otherwise NULL. */ 226 tree this_entity; 227 228 /* The binding level which this one is contained in (inherits from). */ 229 struct cp_binding_level *level_chain; 230 231 /* List of VAR_DECLS saved from a previous for statement. 232 These would be dead in ISO-conforming code, but might 233 be referenced in ARM-era code. These are stored in a 234 TREE_LIST; the TREE_VALUE is the actual declaration. */ 235 tree dead_vars_from_for; 236 237 /* STATEMENT_LIST for statements in this binding contour. 238 Only used at present for SK_CLEANUP temporary bindings. */ 239 tree statement_list; 240 241 /* Binding depth at which this level began. */ 242 int binding_depth; 243 244 /* The kind of scope that this object represents. However, a 245 SK_TEMPLATE_SPEC scope is represented with KIND set to 246 SK_TEMPLATE_PARMS and EXPLICIT_SPEC_P set to true. */ 247 ENUM_BITFIELD (scope_kind) kind : 4; 248 249 /* True if this scope is an SK_TEMPLATE_SPEC scope. This field is 250 only valid if KIND == SK_TEMPLATE_PARMS. */ 251 BOOL_BITFIELD explicit_spec_p : 1; 252 253 /* true means make a BLOCK for this level regardless of all else. */ 254 unsigned keep : 1; 255 256 /* Nonzero if this level can safely have additional 257 cleanup-needing variables added to it. */ 258 unsigned more_cleanups_ok : 1; 259 unsigned have_cleanups : 1; 260 261 /* 22 bits left to fill a 32-bit word. */ 262 }; 263 264/* The binding level currently in effect. */ 265 266#define current_binding_level \ 267 (*(cfun && cp_function_chain->bindings \ 268 ? &cp_function_chain->bindings \ 269 : &scope_chain->bindings)) 270 271/* The binding level of the current class, if any. */ 272 273#define class_binding_level scope_chain->class_bindings 274 275/* The tree node representing the global scope. */ 276extern GTY(()) tree global_namespace; 277extern GTY(()) tree global_scope_name; 278 279/* Indicates that there is a type value in some namespace, although 280 that is not necessarily in scope at the moment. */ 281 282extern GTY(()) tree global_type_node; 283 284/* True if SCOPE designates the global scope binding contour. */ 285#define global_scope_p(SCOPE) \ 286 ((SCOPE) == NAMESPACE_LEVEL (global_namespace)) 287 288extern cxx_scope *leave_scope (void); 289extern bool kept_level_p (void); 290extern int global_bindings_p (void); 291extern bool toplevel_bindings_p (void); 292extern bool namespace_bindings_p (void); 293extern bool template_parm_scope_p (void); 294extern scope_kind innermost_scope_kind (void); 295extern cxx_scope *begin_scope (scope_kind, tree); 296extern void print_binding_stack (void); 297extern void push_to_top_level (void); 298extern void pop_from_top_level (void); 299extern void pop_everything (void); 300extern void keep_next_level (bool); 301extern bool is_ancestor (tree, tree); 302extern tree push_scope (tree); 303extern void pop_scope (tree); 304extern tree push_inner_scope (tree); 305extern void pop_inner_scope (tree, tree); 306extern void push_binding_level (struct cp_binding_level *); 307 308extern void push_namespace (tree); 309extern void pop_namespace (void); 310extern void push_nested_namespace (tree); 311extern void pop_nested_namespace (tree); 312extern void pushlevel_class (void); 313extern void poplevel_class (void); 314extern tree pushdecl_with_scope (tree, cxx_scope *, bool); 315extern tree lookup_name (tree, int); 316extern tree lookup_name_one (tree); 317extern tree lookup_name_real (tree, int, int, bool, int, int); 318extern tree lookup_type_scope (tree, tag_scope); 319extern tree namespace_binding (tree, tree); 320extern void set_namespace_binding (tree, tree, tree); 321extern bool hidden_name_p (tree); 322extern tree remove_hidden_names (tree); 323extern tree lookup_namespace_name (tree, tree); 324extern tree lookup_qualified_name (tree, tree, bool, bool); 325extern tree lookup_name_nonclass (tree); 326extern tree lookup_function_nonclass (tree, tree, bool); 327extern void push_local_binding (tree, tree, int); 328extern bool pushdecl_class_level (tree); 329extern tree pushdecl_namespace_level (tree, bool); 330extern bool push_class_level_binding (tree, tree); 331extern tree getdecls (void); 332extern tree cp_namespace_decls (tree); 333extern void set_decl_namespace (tree, tree, bool); 334extern void push_decl_namespace (tree); 335extern void pop_decl_namespace (void); 336extern void do_namespace_alias (tree, tree); 337extern void do_toplevel_using_decl (tree, tree, tree); 338extern void do_local_using_decl (tree, tree, tree); 339extern tree do_class_using_decl (tree, tree); 340extern void do_using_directive (tree); 341extern tree lookup_arg_dependent (tree, tree, tree); 342extern bool is_associated_namespace (tree, tree); 343extern void parse_using_directive (tree, tree); 344extern tree innermost_non_namespace_value (tree); 345extern cxx_binding *outer_binding (tree, cxx_binding *, bool); 346extern void cp_emit_debug_info_for_using (tree, tree); 347 348/* Set *DECL to the (non-hidden) declaration for ID at global scope, 349 if present and return true; otherwise return false. */ 350 351static inline bool 352get_global_value_if_present (tree id, tree *decl) 353{ 354 tree global_value = namespace_binding (id, global_namespace); 355 if (global_value) 356 *decl = global_value; 357 return global_value != NULL; 358} 359 360/* True is the binding of IDENTIFIER at global scope names a type. */ 361 362static inline bool 363is_typename_at_global_scope (tree id) 364{ 365 tree global_value = namespace_binding (id, global_namespace); 366 367 return global_value && TREE_CODE (global_value) == TYPE_DECL; 368} 369 370#endif /* GCC_CP_NAME_LOOKUP_H */ 371