1 /* Declarations for C++ name lookup routines. 2 Copyright (C) 2003-2018 Free Software Foundation, Inc. 3 Contributed by Gabriel Dos Reis <gdr@integrable-solutions.net> 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3, or (at your option) 10 any later version. 11 12 GCC is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 #ifndef GCC_CP_NAME_LOOKUP_H 22 #define GCC_CP_NAME_LOOKUP_H 23 24 #include "c-family/c-common.h" 25 26 /* The type of dictionary used to map names to types declared at 27 a given scope. */ 28 typedef struct binding_table_s *binding_table; 29 typedef struct binding_entry_s *binding_entry; 30 31 /* The type of a routine repeatedly called by binding_table_foreach. */ 32 typedef void (*bt_foreach_proc) (binding_entry, void *); 33 34 struct GTY(()) binding_entry_s { 35 binding_entry chain; 36 tree name; 37 tree type; 38 }; 39 40 /* These macros indicate the initial chains count for binding_table. */ 41 #define SCOPE_DEFAULT_HT_SIZE (1 << 3) 42 #define CLASS_SCOPE_HT_SIZE (1 << 3) 43 #define NAMESPACE_ORDINARY_HT_SIZE (1 << 5) 44 #define NAMESPACE_STD_HT_SIZE (1 << 8) 45 #define GLOBAL_SCOPE_HT_SIZE (1 << 8) 46 47 extern void binding_table_foreach (binding_table, bt_foreach_proc, void *); 48 extern binding_entry binding_table_find (binding_table, tree); 49 50 /* Datatype that represents binding established by a declaration between 51 a name and a C++ entity. */ 52 typedef struct cxx_binding cxx_binding; 53 54 /* The datatype used to implement C++ scope. */ 55 typedef struct cp_binding_level cp_binding_level; 56 57 /* Nonzero if this binding is for a local scope, as opposed to a class 58 or namespace scope. */ 59 #define LOCAL_BINDING_P(NODE) ((NODE)->is_local) 60 61 /* True if NODE->value is from a base class of the class which is 62 currently being defined. */ 63 #define INHERITED_VALUE_BINDING_P(NODE) ((NODE)->value_is_inherited) 64 65 struct GTY(()) cxx_binding { 66 /* Link to chain together various bindings for this name. */ 67 cxx_binding *previous; 68 /* The non-type entity this name is bound to. */ 69 tree value; 70 /* The type entity this name is bound to. */ 71 tree type; 72 /* The scope at which this binding was made. */ 73 cp_binding_level *scope; 74 unsigned value_is_inherited : 1; 75 unsigned is_local : 1; 76 }; 77 78 /* Datatype used to temporarily save C++ bindings (for implicit 79 instantiations purposes and like). Implemented in decl.c. */ 80 struct GTY(()) cxx_saved_binding { 81 /* The name of the current binding. */ 82 tree identifier; 83 /* The binding we're saving. */ 84 cxx_binding *binding; 85 tree real_type_value; 86 }; 87 88 89 extern tree identifier_type_value (tree); 90 extern void set_identifier_type_value (tree, tree); 91 extern void push_binding (tree, tree, cp_binding_level*); 92 extern void pop_local_binding (tree, tree); 93 extern void pop_bindings_and_leave_scope (void); 94 extern tree constructor_name (tree); 95 extern bool constructor_name_p (tree, tree); 96 97 /* The kinds of scopes we recognize. */ 98 enum scope_kind { 99 sk_block = 0, /* An ordinary block scope. This enumerator must 100 have the value zero because "cp_binding_level" 101 is initialized by using "memset" to set the 102 contents to zero, and the default scope kind 103 is "sk_block". */ 104 sk_cleanup, /* A scope for (pseudo-)scope for cleanup. It is 105 pseudo in that it is transparent to name lookup 106 activities. */ 107 sk_try, /* A try-block. */ 108 sk_catch, /* A catch-block. */ 109 sk_for, /* The scope of the variable declared in a 110 init-statement. */ 111 sk_cond, /* The scope of the variable declared in the condition 112 of an if or switch statement. */ 113 sk_function_parms, /* The scope containing function parameters. */ 114 sk_class, /* The scope containing the members of a class. */ 115 sk_scoped_enum, /* The scope containing the enumertors of a C++0x 116 scoped enumeration. */ 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 sk_transaction, /* A synchronized or atomic statement. */ 125 sk_omp /* An OpenMP structured block. */ 126 }; 127 128 /* The scope where the class/struct/union/enum tag applies. */ 129 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 ts_lambda = 3 /* Declaring a lambda closure. */ 143 }; 144 145 struct GTY(()) cp_class_binding { 146 cxx_binding *base; 147 /* The bound name. */ 148 tree identifier; 149 }; 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 struct GTY(()) cp_binding_level { 173 /* A chain of _DECL nodes for all variables, constants, functions, 174 and typedef types. These are in the reverse of the order 175 supplied. There may be OVERLOADs on this list, too, but they 176 are wrapped in TREE_LISTs; the TREE_VALUE is the OVERLOAD. */ 177 tree names; 178 179 /* A list of USING_DECL nodes. */ 180 tree usings; 181 182 /* Using directives. */ 183 vec<tree, va_gc> *using_directives; 184 185 /* For the binding level corresponding to a class, the entities 186 declared in the class or its base classes. */ 187 vec<cp_class_binding, va_gc> *class_shadowed; 188 189 /* Similar to class_shadowed, but for IDENTIFIER_TYPE_VALUE, and 190 is used for all binding levels. The TREE_PURPOSE is the name of 191 the entity, the TREE_TYPE is the associated type. In addition 192 the TREE_VALUE is the IDENTIFIER_TYPE_VALUE before we entered 193 the class. */ 194 tree type_shadowed; 195 196 /* For each level (except not the global one), 197 a chain of BLOCK nodes for all the levels 198 that were entered and exited one level down. */ 199 tree blocks; 200 201 /* The entity (namespace, class, function) the scope of which this 202 binding contour corresponds to. Otherwise NULL. */ 203 tree this_entity; 204 205 /* The binding level which this one is contained in (inherits from). */ 206 cp_binding_level *level_chain; 207 208 /* List of VAR_DECLS saved from a previous for statement. 209 These would be dead in ISO-conforming code, but might 210 be referenced in ARM-era code. */ 211 vec<tree, va_gc> *dead_vars_from_for; 212 213 /* STATEMENT_LIST for statements in this binding contour. 214 Only used at present for SK_CLEANUP temporary bindings. */ 215 tree statement_list; 216 217 /* Binding depth at which this level began. */ 218 int binding_depth; 219 220 /* The kind of scope that this object represents. However, a 221 SK_TEMPLATE_SPEC scope is represented with KIND set to 222 SK_TEMPLATE_PARMS and EXPLICIT_SPEC_P set to true. */ 223 ENUM_BITFIELD (scope_kind) kind : 4; 224 225 /* True if this scope is an SK_TEMPLATE_SPEC scope. This field is 226 only valid if KIND == SK_TEMPLATE_PARMS. */ 227 BOOL_BITFIELD explicit_spec_p : 1; 228 229 /* true means make a BLOCK for this level regardless of all else. */ 230 unsigned keep : 1; 231 232 /* Nonzero if this level can safely have additional 233 cleanup-needing variables added to it. */ 234 unsigned more_cleanups_ok : 1; 235 unsigned have_cleanups : 1; 236 237 /* Transient state set if this scope is of sk_class kind 238 and is in the process of defining 'this_entity'. Reset 239 on leaving the class definition to allow for the scope 240 to be subsequently re-used as a non-defining scope for 241 'this_entity'. */ 242 unsigned defining_class_p : 1; 243 244 /* 23 bits left to fill a 32-bit word. */ 245 }; 246 247 /* The binding level currently in effect. */ 248 249 #define current_binding_level \ 250 (*(cfun && cp_function_chain && cp_function_chain->bindings \ 251 ? &cp_function_chain->bindings \ 252 : &scope_chain->bindings)) 253 254 /* The binding level of the current class, if any. */ 255 256 #define class_binding_level scope_chain->class_bindings 257 258 /* True if SCOPE designates the global scope binding contour. */ 259 #define global_scope_p(SCOPE) \ 260 ((SCOPE) == NAMESPACE_LEVEL (global_namespace)) 261 262 extern cp_binding_level *leave_scope (void); 263 extern bool kept_level_p (void); 264 extern bool global_bindings_p (void); 265 extern bool toplevel_bindings_p (void); 266 extern bool namespace_bindings_p (void); 267 extern bool local_bindings_p (void); 268 extern bool template_parm_scope_p (void); 269 extern scope_kind innermost_scope_kind (void); 270 extern cp_binding_level *begin_scope (scope_kind, tree); 271 extern void print_binding_stack (void); 272 extern void pop_everything (void); 273 extern void keep_next_level (bool); 274 extern bool is_ancestor (tree ancestor, tree descendant); 275 extern bool is_nested_namespace (tree parent, tree descendant, 276 bool inline_only = false); 277 extern tree push_scope (tree); 278 extern void pop_scope (tree); 279 extern tree push_inner_scope (tree); 280 extern void pop_inner_scope (tree, tree); 281 extern void push_binding_level (cp_binding_level *); 282 283 extern bool handle_namespace_attrs (tree, tree); 284 extern void pushlevel_class (void); 285 extern void poplevel_class (void); 286 extern tree lookup_name_prefer_type (tree, int); 287 extern tree lookup_name_real (tree, int, int, bool, int, int); 288 extern tree lookup_type_scope (tree, tag_scope); 289 extern tree get_namespace_binding (tree ns, tree id); 290 extern void set_global_binding (tree decl); 291 inline tree get_global_binding (tree id) 292 { 293 return get_namespace_binding (NULL_TREE, id); 294 } 295 extern tree lookup_qualified_name (tree, tree, int, bool, /*hidden*/bool = false); 296 extern tree lookup_name_nonclass (tree); 297 extern bool is_local_extern (tree); 298 extern bool pushdecl_class_level (tree); 299 extern tree pushdecl_namespace_level (tree, bool); 300 extern bool push_class_level_binding (tree, tree); 301 extern tree get_local_decls (); 302 extern int function_parm_depth (void); 303 extern tree cp_namespace_decls (tree); 304 extern void set_decl_namespace (tree, tree, bool); 305 extern void push_decl_namespace (tree); 306 extern void pop_decl_namespace (void); 307 extern void do_namespace_alias (tree, tree); 308 extern tree do_class_using_decl (tree, tree); 309 extern tree lookup_arg_dependent (tree, tree, vec<tree, va_gc> *); 310 extern tree search_anon_aggr (tree, tree, bool = false); 311 extern tree get_class_binding_direct (tree, tree, int type_or_fns = -1); 312 extern tree get_class_binding (tree, tree, int type_or_fns = -1); 313 extern tree *find_member_slot (tree klass, tree name); 314 extern tree *add_member_slot (tree klass, tree name); 315 extern void resort_type_member_vec (void *, void *, 316 gt_pointer_operator, void *); 317 extern void set_class_bindings (tree, unsigned extra = 0); 318 extern void insert_late_enum_def_bindings (tree, tree); 319 extern tree innermost_non_namespace_value (tree); 320 extern cxx_binding *outer_binding (tree, cxx_binding *, bool); 321 extern void cp_emit_debug_info_for_using (tree, tree); 322 323 extern void finish_namespace_using_decl (tree, tree, tree); 324 extern void finish_local_using_decl (tree, tree, tree); 325 extern void finish_namespace_using_directive (tree, tree); 326 extern void finish_local_using_directive (tree, tree); 327 extern tree pushdecl (tree, bool is_friend = false); 328 extern tree pushdecl_outermost_localscope (tree); 329 extern tree pushdecl_top_level (tree, bool is_friend = false); 330 extern tree pushdecl_top_level_and_finish (tree, tree); 331 extern tree pushtag (tree, tree, tag_scope); 332 extern int push_namespace (tree, bool make_inline = false); 333 extern void pop_namespace (void); 334 extern void push_nested_namespace (tree); 335 extern void pop_nested_namespace (tree); 336 extern void push_to_top_level (void); 337 extern void pop_from_top_level (void); 338 339 #endif /* GCC_CP_NAME_LOOKUP_H */ 340