1/* Declarations for C++ name lookup routines. 2 Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009 3 Free Software Foundation, Inc. 4 Contributed by Gabriel Dos Reis <gdr@integrable-solutions.net> 5 6This file is part of GCC. 7 8GCC is free software; you can redistribute it and/or modify 9it under the terms of the GNU General Public License as published by 10the Free Software Foundation; either version 3, or (at your option) 11any later version. 12 13GCC is distributed in the hope that it will be useful, 14but WITHOUT ANY WARRANTY; without even the implied warranty of 15MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16GNU General Public License for more details. 17 18You should have received a copy of the GNU General Public License 19along 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-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 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 48extern void binding_table_foreach (binding_table, bt_foreach_proc, void *); 49extern 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. */ 53typedef struct cxx_binding cxx_binding; 54 55/* The datatype used to implement C++ scope. */ 56typedef struct cp_binding_level cxx_scope; 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 66struct 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 cxx_scope *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. */ 81typedef 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 89DEF_VEC_O(cxx_saved_binding); 90DEF_VEC_ALLOC_O(cxx_saved_binding,gc); 91 92extern tree identifier_type_value (tree); 93extern void set_identifier_type_value (tree, tree); 94extern void pop_binding (tree, tree); 95extern tree constructor_name (tree); 96extern bool constructor_name_p (tree, tree); 97 98/* The kinds of scopes we recognize. */ 99typedef 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_function_parms, /* The scope containing function parameters. */ 113 sk_class, /* The scope containing the members of a class. */ 114 sk_scoped_enum, /* The scope containing the enumertors of a C++0x 115 scoped enumeration. */ 116 sk_namespace, /* The scope containing the members of a 117 namespace, including the global scope. */ 118 sk_template_parms, /* A scope for template parameters. */ 119 sk_template_spec, /* Like sk_template_parms, but for an explicit 120 specialization. Since, by definition, an 121 explicit specialization is introduced by 122 "template <>", this scope is always empty. */ 123 sk_omp /* An OpenMP structured block. */ 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 GTY(()) cp_class_binding { 143 cxx_binding base; 144 /* The bound name. */ 145 tree identifier; 146} cp_class_binding; 147 148DEF_VEC_O(cp_class_binding); 149DEF_VEC_ALLOC_O(cp_class_binding,gc); 150 151/* For each binding contour we allocate a binding_level structure 152 which records the names defined in that contour. 153 Contours include: 154 0) the global one 155 1) one for each function definition, 156 where internal declarations of the parameters appear. 157 2) one for each compound statement, 158 to record its declarations. 159 160 The current meaning of a name can be found by searching the levels 161 from the current one out to the global one. 162 163 Off to the side, may be the class_binding_level. This exists only 164 to catch class-local declarations. It is otherwise nonexistent. 165 166 Also there may be binding levels that catch cleanups that must be 167 run when exceptions occur. Thus, to see whether a name is bound in 168 the current scope, it is not enough to look in the 169 CURRENT_BINDING_LEVEL. You should use lookup_name_current_level 170 instead. */ 171 172/* Note that the information in the `names' component of the global contour 173 is duplicated in the IDENTIFIER_GLOBAL_VALUEs of all identifiers. */ 174 175struct GTY(()) cp_binding_level { 176 /* A chain of _DECL nodes for all variables, constants, functions, 177 and typedef types. These are in the reverse of the order 178 supplied. There may be OVERLOADs on this list, too, but they 179 are wrapped in TREE_LISTs; the TREE_VALUE is the OVERLOAD. */ 180 tree names; 181 182 /* Count of elements in names chain. */ 183 size_t names_size; 184 185 /* A chain of NAMESPACE_DECL nodes. */ 186 tree namespaces; 187 188 /* An array of static functions and variables (for namespaces only) */ 189 VEC(tree,gc) *static_decls; 190 191 /* A list of USING_DECL nodes. */ 192 tree usings; 193 194 /* A list of used namespaces. PURPOSE is the namespace, 195 VALUE the common ancestor with this binding_level's namespace. */ 196 tree using_directives; 197 198 /* For the binding level corresponding to a class, the entities 199 declared in the class or its base classes. */ 200 VEC(cp_class_binding,gc) *class_shadowed; 201 202 /* Similar to class_shadowed, but for IDENTIFIER_TYPE_VALUE, and 203 is used for all binding levels. The TREE_PURPOSE is the name of 204 the entity, the TREE_TYPE is the associated type. In addition 205 the TREE_VALUE is the IDENTIFIER_TYPE_VALUE before we entered 206 the class. */ 207 tree type_shadowed; 208 209 /* A TREE_LIST. Each TREE_VALUE is the LABEL_DECL for a local 210 label in this scope. The TREE_PURPOSE is the previous value of 211 the IDENTIFIER_LABEL VALUE. */ 212 tree shadowed_labels; 213 214 /* For each level (except not the global one), 215 a chain of BLOCK nodes for all the levels 216 that were entered and exited one level down. */ 217 tree blocks; 218 219 /* The entity (namespace, class, function) the scope of which this 220 binding contour corresponds to. Otherwise NULL. */ 221 tree this_entity; 222 223 /* The binding level which this one is contained in (inherits from). */ 224 struct cp_binding_level *level_chain; 225 226 /* List of VAR_DECLS saved from a previous for statement. 227 These would be dead in ISO-conforming code, but might 228 be referenced in ARM-era code. These are stored in a 229 TREE_LIST; the TREE_VALUE is the actual declaration. */ 230 tree dead_vars_from_for; 231 232 /* STATEMENT_LIST for statements in this binding contour. 233 Only used at present for SK_CLEANUP temporary bindings. */ 234 tree statement_list; 235 236 /* Binding depth at which this level began. */ 237 int binding_depth; 238 239 /* The kind of scope that this object represents. However, a 240 SK_TEMPLATE_SPEC scope is represented with KIND set to 241 SK_TEMPLATE_PARMS and EXPLICIT_SPEC_P set to true. */ 242 ENUM_BITFIELD (scope_kind) kind : 4; 243 244 /* True if this scope is an SK_TEMPLATE_SPEC scope. This field is 245 only valid if KIND == SK_TEMPLATE_PARMS. */ 246 BOOL_BITFIELD explicit_spec_p : 1; 247 248 /* true means make a BLOCK for this level regardless of all else. */ 249 unsigned keep : 1; 250 251 /* Nonzero if this level can safely have additional 252 cleanup-needing variables added to it. */ 253 unsigned more_cleanups_ok : 1; 254 unsigned have_cleanups : 1; 255 256 /* 24 bits left to fill a 32-bit word. */ 257 }; 258 259/* The binding level currently in effect. */ 260 261#define current_binding_level \ 262 (*(cfun && cp_function_chain && cp_function_chain->bindings \ 263 ? &cp_function_chain->bindings \ 264 : &scope_chain->bindings)) 265 266/* The binding level of the current class, if any. */ 267 268#define class_binding_level scope_chain->class_bindings 269 270/* The tree node representing the global scope. */ 271extern GTY(()) tree global_namespace; 272extern GTY(()) tree global_scope_name; 273 274/* Indicates that there is a type value in some namespace, although 275 that is not necessarily in scope at the moment. */ 276 277extern GTY(()) tree global_type_node; 278 279/* True if SCOPE designates the global scope binding contour. */ 280#define global_scope_p(SCOPE) \ 281 ((SCOPE) == NAMESPACE_LEVEL (global_namespace)) 282 283extern cxx_scope *leave_scope (void); 284extern bool kept_level_p (void); 285extern int global_bindings_p (void); 286extern bool toplevel_bindings_p (void); 287extern bool namespace_bindings_p (void); 288extern bool template_parm_scope_p (void); 289extern scope_kind innermost_scope_kind (void); 290extern cxx_scope *begin_scope (scope_kind, tree); 291extern void print_binding_stack (void); 292extern void push_to_top_level (void); 293extern void pop_from_top_level (void); 294extern void pop_everything (void); 295extern void keep_next_level (bool); 296extern bool is_ancestor (tree, tree); 297extern tree push_scope (tree); 298extern void pop_scope (tree); 299extern tree push_inner_scope (tree); 300extern void pop_inner_scope (tree, tree); 301extern void push_binding_level (struct cp_binding_level *); 302 303extern void push_namespace (tree); 304extern void pop_namespace (void); 305extern void push_nested_namespace (tree); 306extern void pop_nested_namespace (tree); 307extern bool handle_namespace_attrs (tree, tree); 308extern void pushlevel_class (void); 309extern void poplevel_class (void); 310extern tree pushdecl_with_scope (tree, cxx_scope *, bool); 311extern tree lookup_name_prefer_type (tree, int); 312extern tree lookup_name_real (tree, int, int, bool, int, int); 313extern tree lookup_type_scope (tree, tag_scope); 314extern tree namespace_binding (tree, tree); 315extern void set_namespace_binding (tree, tree, tree); 316extern bool hidden_name_p (tree); 317extern tree remove_hidden_names (tree); 318extern tree lookup_qualified_name (tree, tree, bool, bool); 319extern tree lookup_name_nonclass (tree); 320extern tree lookup_name_innermost_nonclass_level (tree); 321extern bool is_local_extern (tree); 322extern tree lookup_function_nonclass (tree, VEC(tree,gc) *, bool); 323extern void push_local_binding (tree, tree, int); 324extern bool pushdecl_class_level (tree); 325extern tree pushdecl_namespace_level (tree, bool); 326extern bool push_class_level_binding (tree, tree); 327extern tree getdecls (void); 328extern tree cp_namespace_decls (tree); 329extern void set_decl_namespace (tree, tree, bool); 330extern void push_decl_namespace (tree); 331extern void pop_decl_namespace (void); 332extern void do_namespace_alias (tree, tree); 333extern void do_toplevel_using_decl (tree, tree, tree); 334extern void do_local_using_decl (tree, tree, tree); 335extern tree do_class_using_decl (tree, tree); 336extern void do_using_directive (tree); 337extern tree lookup_arg_dependent (tree, tree, VEC(tree,gc) *); 338extern bool is_associated_namespace (tree, tree); 339extern void parse_using_directive (tree, tree); 340extern tree innermost_non_namespace_value (tree); 341extern cxx_binding *outer_binding (tree, cxx_binding *, bool); 342extern void cp_emit_debug_info_for_using (tree, tree); 343 344/* Set *DECL to the (non-hidden) declaration for ID at global scope, 345 if present and return true; otherwise return false. */ 346 347static inline bool 348get_global_value_if_present (tree id, tree *decl) 349{ 350 tree global_value = namespace_binding (id, global_namespace); 351 if (global_value) 352 *decl = global_value; 353 return global_value != NULL; 354} 355 356/* True is the binding of IDENTIFIER at global scope names a type. */ 357 358static inline bool 359is_typename_at_global_scope (tree id) 360{ 361 tree global_value = namespace_binding (id, global_namespace); 362 363 return global_value && TREE_CODE (global_value) == TYPE_DECL; 364} 365 366#endif /* GCC_CP_NAME_LOOKUP_H */ 367