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 /* APPLE LOCAL blocks 6040305 (ch) */ 80 unsigned declared_in_block : 1; 81}; 82 83/* Datatype used to temporarily save C++ bindings (for implicit 84 instantiations purposes and like). Implemented in decl.c. */ 85typedef struct cxx_saved_binding GTY(()) 86{ 87 /* The name of the current binding. */ 88 tree identifier; 89 /* The binding we're saving. */ 90 cxx_binding *binding; 91 tree real_type_value; 92} cxx_saved_binding; 93 94DEF_VEC_O(cxx_saved_binding); 95DEF_VEC_ALLOC_O(cxx_saved_binding,gc); 96 97extern tree identifier_type_value (tree); 98extern void set_identifier_type_value (tree, tree); 99extern void pop_binding (tree, tree); 100extern tree constructor_name (tree); 101extern bool constructor_name_p (tree, tree); 102 103/* The kinds of scopes we recognize. */ 104typedef 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_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. */ 130typedef 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 145typedef struct cp_class_binding GTY(()) 146{ 147 cxx_binding *base; 148 /* The bound name. */ 149 tree identifier; 150} cp_class_binding; 151 152DEF_VEC_O(cp_class_binding); 153DEF_VEC_ALLOC_O(cp_class_binding,gc); 154 155/* For each binding contour we allocate a binding_level structure 156 which records the names defined in that contour. 157 Contours include: 158 0) the global one 159 1) one for each function definition, 160 where internal declarations of the parameters appear. 161 2) one for each compound statement, 162 to record its declarations. 163 164 The current meaning of a name can be found by searching the levels 165 from the current one out to the global one. 166 167 Off to the side, may be the class_binding_level. This exists only 168 to catch class-local declarations. It is otherwise nonexistent. 169 170 Also there may be binding levels that catch cleanups that must be 171 run when exceptions occur. Thus, to see whether a name is bound in 172 the current scope, it is not enough to look in the 173 CURRENT_BINDING_LEVEL. You should use lookup_name_current_level 174 instead. */ 175 176/* Note that the information in the `names' component of the global contour 177 is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers. */ 178 179struct cp_binding_level GTY(()) 180 { 181 /* A chain of _DECL nodes for all variables, constants, functions, 182 and typedef types. These are in the reverse of the order 183 supplied. There may be OVERLOADs on this list, too, but they 184 are wrapped in TREE_LISTs; the TREE_VALUE is the OVERLOAD. */ 185 tree names; 186 187 /* Count of elements in names chain. */ 188 size_t names_size; 189 190 /* A chain of NAMESPACE_DECL nodes. */ 191 tree namespaces; 192 193 /* An array of static functions and variables (for namespaces only) */ 194 VEC(tree,gc) *static_decls; 195 196 /* A chain of VTABLE_DECL nodes. */ 197 tree vtables; 198 199 /* A list of USING_DECL nodes. */ 200 tree usings; 201 202 /* A list of used namespaces. PURPOSE is the namespace, 203 VALUE the common ancestor with this binding_level's namespace. */ 204 tree using_directives; 205 206 /* For the binding level corresponding to a class, the entities 207 declared in the class or its base classes. */ 208 VEC(cp_class_binding,gc) *class_shadowed; 209 210 /* Similar to class_shadowed, but for IDENTIFIER_TYPE_VALUE, and 211 is used for all binding levels. The TREE_PURPOSE is the name of 212 the entity, the TREE_TYPE is the associated type. In addition 213 the TREE_VALUE is the IDENTIFIER_TYPE_VALUE before we entered 214 the class. */ 215 tree type_shadowed; 216 217 /* A TREE_LIST. Each TREE_VALUE is the LABEL_DECL for a local 218 label in this scope. The TREE_PURPOSE is the previous value of 219 the IDENTIFIER_LABEL VALUE. */ 220 tree 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 struct 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. These are stored in a 237 TREE_LIST; the TREE_VALUE is the actual declaration. */ 238 tree dead_vars_from_for; 239 240 /* STATEMENT_LIST for statements in this binding contour. 241 Only used at present for SK_CLEANUP temporary bindings. */ 242 tree statement_list; 243 244 /* Binding depth at which this level began. */ 245 int binding_depth; 246 247 /* The kind of scope that this object represents. However, a 248 SK_TEMPLATE_SPEC scope is represented with KIND set to 249 SK_TEMPLATE_PARMS and EXPLICIT_SPEC_P set to true. */ 250 ENUM_BITFIELD (scope_kind) kind : 4; 251 252 /* True if this scope is an SK_TEMPLATE_SPEC scope. This field is 253 only valid if KIND == SK_TEMPLATE_PARMS. */ 254 BOOL_BITFIELD explicit_spec_p : 1; 255 256 /* true means make a BLOCK for this level regardless of all else. */ 257 unsigned keep : 1; 258 259 /* Nonzero if this level can safely have additional 260 cleanup-needing variables added to it. */ 261 unsigned more_cleanups_ok : 1; 262 unsigned have_cleanups : 1; 263 264 /* Nonzero if this level has associated visibility which we should pop 265 when leaving the scope. */ 266 unsigned has_visibility : 1; 267 268 /* 23 bits left to fill a 32-bit word. */ 269 }; 270 271/* The binding level currently in effect. */ 272 273#define current_binding_level \ 274 (*(cfun && cp_function_chain->bindings \ 275 ? &cp_function_chain->bindings \ 276 : &scope_chain->bindings)) 277 278/* The binding level of the current class, if any. */ 279 280#define class_binding_level scope_chain->class_bindings 281 282/* The tree node representing the global scope. */ 283extern GTY(()) tree global_namespace; 284extern GTY(()) tree global_scope_name; 285 286/* Indicates that there is a type value in some namespace, although 287 that is not necessarily in scope at the moment. */ 288 289extern GTY(()) tree global_type_node; 290 291/* True if SCOPE designates the global scope binding contour. */ 292#define global_scope_p(SCOPE) \ 293 ((SCOPE) == NAMESPACE_LEVEL (global_namespace)) 294 295extern cxx_scope *leave_scope (void); 296extern bool kept_level_p (void); 297extern int global_bindings_p (void); 298extern bool toplevel_bindings_p (void); 299extern bool namespace_bindings_p (void); 300extern bool template_parm_scope_p (void); 301extern scope_kind innermost_scope_kind (void); 302extern cxx_scope *begin_scope (scope_kind, tree); 303extern void print_binding_stack (void); 304extern void push_to_top_level (void); 305extern void pop_from_top_level (void); 306extern void pop_everything (void); 307extern void keep_next_level (bool); 308extern bool is_ancestor (tree, tree); 309extern tree push_scope (tree); 310extern void pop_scope (tree); 311extern tree push_inner_scope (tree); 312extern void pop_inner_scope (tree, tree); 313extern void push_binding_level (struct cp_binding_level *); 314 315extern void push_namespace (tree); 316extern void push_namespace_with_attribs (tree, tree); 317extern void pop_namespace (void); 318extern void push_nested_namespace (tree); 319extern void pop_nested_namespace (tree); 320extern void pushlevel_class (void); 321extern void poplevel_class (void); 322extern tree pushdecl_with_scope (tree, cxx_scope *, bool); 323extern tree lookup_name_prefer_type (tree, int); 324extern tree lookup_name_real (tree, int, int, bool, int, int); 325extern tree lookup_type_scope (tree, tag_scope); 326extern tree namespace_binding (tree, tree); 327extern void set_namespace_binding (tree, tree, tree); 328extern bool hidden_name_p (tree); 329extern tree remove_hidden_names (tree); 330extern tree lookup_qualified_name (tree, tree, bool, bool); 331extern tree lookup_name_nonclass (tree); 332extern tree lookup_function_nonclass (tree, tree, bool); 333extern void push_local_binding (tree, tree, int); 334extern bool pushdecl_class_level (tree); 335extern tree pushdecl_namespace_level (tree, bool); 336extern bool push_class_level_binding (tree, tree); 337extern tree getdecls (void); 338extern tree cp_namespace_decls (tree); 339extern void set_decl_namespace (tree, tree, bool); 340extern void push_decl_namespace (tree); 341extern void pop_decl_namespace (void); 342extern void do_namespace_alias (tree, tree); 343extern void do_toplevel_using_decl (tree, tree, tree); 344extern void do_local_using_decl (tree, tree, tree); 345extern tree do_class_using_decl (tree, tree); 346extern void do_using_directive (tree); 347extern tree lookup_arg_dependent (tree, tree, tree); 348extern bool is_associated_namespace (tree, tree); 349extern void parse_using_directive (tree, tree); 350extern tree innermost_non_namespace_value (tree); 351extern cxx_binding *outer_binding (tree, cxx_binding *, bool); 352extern void cp_emit_debug_info_for_using (tree, tree); 353 354/* Set *DECL to the (non-hidden) declaration for ID at global scope, 355 if present and return true; otherwise return false. */ 356 357static inline bool 358get_global_value_if_present (tree id, tree *decl) 359{ 360 tree global_value = namespace_binding (id, global_namespace); 361 if (global_value) 362 *decl = global_value; 363 return global_value != NULL; 364} 365 366/* True is the binding of IDENTIFIER at global scope names a type. */ 367 368static inline bool 369is_typename_at_global_scope (tree id) 370{ 371 tree global_value = namespace_binding (id, global_namespace); 372 373 return global_value && TREE_CODE (global_value) == TYPE_DECL; 374} 375 376#endif /* GCC_CP_NAME_LOOKUP_H */ 377