1 /* Some code common to C++ and ObjC++ front ends. 2 Copyright (C) 2004-2018 Free Software Foundation, Inc. 3 Contributed by Ziemowit Laski <zlaski@apple.com> 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify it under 8 the terms of the GNU General Public License as published by the Free 9 Software Foundation; either version 3, or (at your option) any later 10 version. 11 12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13 WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15 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 #include "config.h" 22 #include "system.h" 23 #include "coretypes.h" 24 #include "cp-tree.h" 25 #include "cp-objcp-common.h" 26 #include "dwarf2.h" 27 28 /* Special routine to get the alias set for C++. */ 29 30 alias_set_type 31 cxx_get_alias_set (tree t) 32 { 33 if (IS_FAKE_BASE_TYPE (t)) 34 /* The base variant of a type must be in the same alias set as the 35 complete type. */ 36 return get_alias_set (TYPE_CONTEXT (t)); 37 38 /* Punt on PMFs until we canonicalize functions properly. */ 39 if (TYPE_PTRMEMFUNC_P (t) 40 || (POINTER_TYPE_P (t) 41 && TYPE_PTRMEMFUNC_P (TREE_TYPE (t)))) 42 return 0; 43 44 return c_common_get_alias_set (t); 45 } 46 47 /* Called from check_global_declaration. */ 48 49 bool 50 cxx_warn_unused_global_decl (const_tree decl) 51 { 52 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl)) 53 return false; 54 if (DECL_IN_SYSTEM_HEADER (decl)) 55 return false; 56 57 return true; 58 } 59 60 /* Langhook for tree_size: determine size of our 'x' and 'c' nodes. */ 61 size_t 62 cp_tree_size (enum tree_code code) 63 { 64 gcc_checking_assert (code >= NUM_TREE_CODES); 65 switch (code) 66 { 67 case PTRMEM_CST: return sizeof (ptrmem_cst); 68 case BASELINK: return sizeof (tree_baselink); 69 case TEMPLATE_PARM_INDEX: return sizeof (template_parm_index); 70 case DEFAULT_ARG: return sizeof (tree_default_arg); 71 case DEFERRED_NOEXCEPT: return sizeof (tree_deferred_noexcept); 72 case OVERLOAD: return sizeof (tree_overload); 73 case STATIC_ASSERT: return sizeof (tree_static_assert); 74 case TYPE_ARGUMENT_PACK: 75 case TYPE_PACK_EXPANSION: return sizeof (tree_type_non_common); 76 case NONTYPE_ARGUMENT_PACK: 77 case EXPR_PACK_EXPANSION: return sizeof (tree_exp); 78 case ARGUMENT_PACK_SELECT: return sizeof (tree_argument_pack_select); 79 case TRAIT_EXPR: return sizeof (tree_trait_expr); 80 case LAMBDA_EXPR: return sizeof (tree_lambda_expr); 81 case TEMPLATE_INFO: return sizeof (tree_template_info); 82 case CONSTRAINT_INFO: return sizeof (tree_constraint_info); 83 case USERDEF_LITERAL: return sizeof (tree_userdef_literal); 84 case TEMPLATE_DECL: return sizeof (tree_template_decl); 85 default: 86 switch (TREE_CODE_CLASS (code)) 87 { 88 case tcc_declaration: return sizeof (tree_decl_non_common); 89 case tcc_type: return sizeof (tree_type_non_common); 90 default: gcc_unreachable (); 91 } 92 } 93 /* NOTREACHED */ 94 } 95 96 /* Returns true if T is a variably modified type, in the sense of C99. 97 FN is as passed to variably_modified_p. 98 This routine needs only check cases that cannot be handled by the 99 language-independent logic in tree.c. */ 100 101 bool 102 cp_var_mod_type_p (tree type, tree fn) 103 { 104 /* If TYPE is a pointer-to-member, it is variably modified if either 105 the class or the member are variably modified. */ 106 if (TYPE_PTRMEM_P (type)) 107 return (variably_modified_type_p (TYPE_PTRMEM_CLASS_TYPE (type), fn) 108 || variably_modified_type_p (TYPE_PTRMEM_POINTED_TO_TYPE (type), 109 fn)); 110 111 /* All other types are not variably modified. */ 112 return false; 113 } 114 115 /* This compares two types for equivalence ("compatible" in C-based languages). 116 This routine should only return 1 if it is sure. It should not be used 117 in contexts where erroneously returning 0 causes problems. */ 118 119 int 120 cxx_types_compatible_p (tree x, tree y) 121 { 122 return same_type_ignoring_top_level_qualifiers_p (x, y); 123 } 124 125 static GTY((cache)) tree_cache_map *debug_type_map; 126 127 /* Return a type to use in the debug info instead of TYPE, or NULL_TREE to 128 keep TYPE. */ 129 130 tree 131 cp_get_debug_type (const_tree type) 132 { 133 tree dtype = NULL_TREE; 134 135 if (TYPE_PTRMEMFUNC_P (type) && !typedef_variant_p (type)) 136 dtype = build_offset_type (TYPE_PTRMEMFUNC_OBJECT_TYPE (type), 137 TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (type))); 138 139 /* We cannot simply return the debug type here because the function uses 140 the type canonicalization hashtable, which is GC-ed, so its behavior 141 depends on the actual collection points. Since we are building these 142 types on the fly for the debug info only, they would not be attached 143 to any GC root and always be swept, so we would make the contents of 144 the debug info depend on the collection points. */ 145 if (dtype) 146 { 147 tree ktype = CONST_CAST_TREE (type); 148 if (debug_type_map == NULL) 149 debug_type_map = tree_cache_map::create_ggc (512); 150 else if (tree *slot = debug_type_map->get (ktype)) 151 return *slot; 152 debug_type_map->put (ktype, dtype); 153 } 154 155 return dtype; 156 } 157 158 /* Return -1 if dwarf ATTR shouldn't be added for DECL, or the attribute 159 value otherwise. */ 160 int 161 cp_decl_dwarf_attribute (const_tree decl, int attr) 162 { 163 if (decl == NULL_TREE) 164 return -1; 165 166 switch (attr) 167 { 168 case DW_AT_explicit: 169 if (TREE_CODE (decl) == FUNCTION_DECL 170 && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl)) 171 && DECL_NONCONVERTING_P (decl)) 172 return 1; 173 break; 174 175 case DW_AT_deleted: 176 if (TREE_CODE (decl) == FUNCTION_DECL 177 && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl)) 178 && DECL_DELETED_FN (decl)) 179 return 1; 180 break; 181 182 case DW_AT_defaulted: 183 if (TREE_CODE (decl) == FUNCTION_DECL 184 && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl)) 185 && DECL_DEFAULTED_FN (decl)) 186 { 187 if (DECL_DEFAULTED_IN_CLASS_P (decl)) 188 return DW_DEFAULTED_in_class; 189 190 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (decl)) 191 return DW_DEFAULTED_out_of_class; 192 } 193 break; 194 195 case DW_AT_const_expr: 196 if (VAR_OR_FUNCTION_DECL_P (decl) && DECL_DECLARED_CONSTEXPR_P (decl)) 197 return 1; 198 break; 199 200 case DW_AT_reference: 201 if (TREE_CODE (decl) == FUNCTION_DECL 202 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl) 203 && FUNCTION_REF_QUALIFIED (TREE_TYPE (decl)) 204 && !FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (decl))) 205 return 1; 206 break; 207 208 case DW_AT_rvalue_reference: 209 if (TREE_CODE (decl) == FUNCTION_DECL 210 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl) 211 && FUNCTION_REF_QUALIFIED (TREE_TYPE (decl)) 212 && FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (decl))) 213 return 1; 214 break; 215 216 case DW_AT_inline: 217 if (VAR_P (decl) && DECL_INLINE_VAR_P (decl)) 218 { 219 if (DECL_VAR_DECLARED_INLINE_P (decl)) 220 return DW_INL_declared_inlined; 221 else 222 return DW_INL_inlined; 223 } 224 break; 225 226 case DW_AT_export_symbols: 227 if (TREE_CODE (decl) == NAMESPACE_DECL 228 && (DECL_NAMESPACE_INLINE_P (decl) 229 || (DECL_NAME (decl) == NULL_TREE && dwarf_version >= 5))) 230 return 1; 231 break; 232 233 default: 234 break; 235 } 236 237 return -1; 238 } 239 240 /* Return -1 if dwarf ATTR shouldn't be added for TYPE, or the attribute 241 value otherwise. */ 242 int 243 cp_type_dwarf_attribute (const_tree type, int attr) 244 { 245 if (type == NULL_TREE) 246 return -1; 247 248 switch (attr) 249 { 250 case DW_AT_reference: 251 if ((TREE_CODE (type) == FUNCTION_TYPE 252 || TREE_CODE (type) == METHOD_TYPE) 253 && FUNCTION_REF_QUALIFIED (type) 254 && !FUNCTION_RVALUE_QUALIFIED (type)) 255 return 1; 256 break; 257 258 case DW_AT_rvalue_reference: 259 if ((TREE_CODE (type) == FUNCTION_TYPE 260 || TREE_CODE (type) == METHOD_TYPE) 261 && FUNCTION_REF_QUALIFIED (type) 262 && FUNCTION_RVALUE_QUALIFIED (type)) 263 return 1; 264 break; 265 266 default: 267 break; 268 } 269 270 return -1; 271 } 272 273 /* Return the unit size of TYPE without reusable tail padding. */ 274 275 tree 276 cp_unit_size_without_reusable_padding (tree type) 277 { 278 if (CLASS_TYPE_P (type)) 279 return CLASSTYPE_SIZE_UNIT (type); 280 return TYPE_SIZE_UNIT (type); 281 } 282 283 /* Stubs to keep c-opts.c happy. */ 284 void 285 push_file_scope (void) 286 { 287 } 288 289 void 290 pop_file_scope (void) 291 { 292 } 293 294 /* c-pragma.c needs to query whether a decl has extern "C" linkage. */ 295 bool 296 has_c_linkage (const_tree decl) 297 { 298 return DECL_EXTERN_C_P (decl); 299 } 300 301 static GTY ((cache)) 302 hash_table<tree_decl_map_cache_hasher> *shadowed_var_for_decl; 303 304 /* Lookup a shadowed var for FROM, and return it if we find one. */ 305 306 tree 307 decl_shadowed_for_var_lookup (tree from) 308 { 309 struct tree_decl_map *h, in; 310 in.base.from = from; 311 312 h = shadowed_var_for_decl->find_with_hash (&in, DECL_UID (from)); 313 if (h) 314 return h->to; 315 return NULL_TREE; 316 } 317 318 /* Insert a mapping FROM->TO in the shadowed var hashtable. */ 319 320 void 321 decl_shadowed_for_var_insert (tree from, tree to) 322 { 323 struct tree_decl_map *h; 324 325 h = ggc_alloc<tree_decl_map> (); 326 h->base.from = from; 327 h->to = to; 328 *shadowed_var_for_decl->find_slot_with_hash (h, DECL_UID (from), INSERT) = h; 329 } 330 331 void 332 init_shadowed_var_for_decl (void) 333 { 334 shadowed_var_for_decl 335 = hash_table<tree_decl_map_cache_hasher>::create_ggc (512); 336 } 337 338 /* Return true if stmt can fall through. Used by block_may_fallthru 339 default case. */ 340 341 bool 342 cxx_block_may_fallthru (const_tree stmt) 343 { 344 switch (TREE_CODE (stmt)) 345 { 346 case EXPR_STMT: 347 return block_may_fallthru (EXPR_STMT_EXPR (stmt)); 348 349 case THROW_EXPR: 350 return false; 351 352 case IF_STMT: 353 if (block_may_fallthru (THEN_CLAUSE (stmt))) 354 return true; 355 return block_may_fallthru (ELSE_CLAUSE (stmt)); 356 357 case SWITCH_STMT: 358 return (!SWITCH_STMT_ALL_CASES_P (stmt) 359 || !SWITCH_STMT_NO_BREAK_P (stmt) 360 || block_may_fallthru (SWITCH_STMT_BODY (stmt))); 361 362 default: 363 return true; 364 } 365 } 366 367 /* Return the list of decls in the global namespace. */ 368 369 tree 370 cp_get_global_decls () 371 { 372 return NAMESPACE_LEVEL (global_namespace)->names; 373 } 374 375 /* Push DECL into the current scope. */ 376 377 tree 378 cp_pushdecl (tree decl) 379 { 380 return pushdecl (decl); 381 } 382 383 /* Get the global value binding of NAME. Called directly from 384 c-common.c, not via a hook. */ 385 386 tree 387 identifier_global_value (tree name) 388 { 389 return get_global_binding (name); 390 } 391 392 /* Register c++-specific dumps. */ 393 394 void 395 cp_register_dumps (gcc::dump_manager *dumps) 396 { 397 class_dump_id = dumps->dump_register 398 (".class", "lang-class", "lang-class", DK_lang, OPTGROUP_NONE, false); 399 400 raw_dump_id = dumps->dump_register 401 (".raw", "lang-raw", "lang-raw", DK_lang, OPTGROUP_NONE, false); 402 } 403 404 void 405 cp_common_init_ts (void) 406 { 407 MARK_TS_DECL_NON_COMMON (USING_DECL); 408 MARK_TS_DECL_COMMON (TEMPLATE_DECL); 409 MARK_TS_DECL_COMMON (WILDCARD_DECL); 410 411 MARK_TS_COMMON (TEMPLATE_TEMPLATE_PARM); 412 MARK_TS_COMMON (TEMPLATE_TYPE_PARM); 413 MARK_TS_COMMON (TEMPLATE_PARM_INDEX); 414 MARK_TS_COMMON (OVERLOAD); 415 MARK_TS_COMMON (TEMPLATE_INFO); 416 MARK_TS_COMMON (TYPENAME_TYPE); 417 MARK_TS_COMMON (TYPEOF_TYPE); 418 MARK_TS_COMMON (UNDERLYING_TYPE); 419 MARK_TS_COMMON (BASELINK); 420 MARK_TS_COMMON (TYPE_PACK_EXPANSION); 421 MARK_TS_COMMON (TYPE_ARGUMENT_PACK); 422 MARK_TS_COMMON (DECLTYPE_TYPE); 423 MARK_TS_COMMON (BOUND_TEMPLATE_TEMPLATE_PARM); 424 MARK_TS_COMMON (UNBOUND_CLASS_TEMPLATE); 425 426 MARK_TS_TYPED (EXPR_PACK_EXPANSION); 427 MARK_TS_TYPED (SWITCH_STMT); 428 MARK_TS_TYPED (IF_STMT); 429 MARK_TS_TYPED (FOR_STMT); 430 MARK_TS_TYPED (RANGE_FOR_STMT); 431 MARK_TS_TYPED (AGGR_INIT_EXPR); 432 MARK_TS_TYPED (EXPR_STMT); 433 MARK_TS_TYPED (EH_SPEC_BLOCK); 434 MARK_TS_TYPED (CLEANUP_STMT); 435 MARK_TS_TYPED (SCOPE_REF); 436 MARK_TS_TYPED (CAST_EXPR); 437 MARK_TS_TYPED (NON_DEPENDENT_EXPR); 438 MARK_TS_TYPED (MODOP_EXPR); 439 MARK_TS_TYPED (TRY_BLOCK); 440 MARK_TS_TYPED (THROW_EXPR); 441 MARK_TS_TYPED (HANDLER); 442 MARK_TS_TYPED (REINTERPRET_CAST_EXPR); 443 MARK_TS_TYPED (CONST_CAST_EXPR); 444 MARK_TS_TYPED (STATIC_CAST_EXPR); 445 MARK_TS_TYPED (DYNAMIC_CAST_EXPR); 446 MARK_TS_TYPED (IMPLICIT_CONV_EXPR); 447 MARK_TS_TYPED (TEMPLATE_ID_EXPR); 448 MARK_TS_TYPED (ARROW_EXPR); 449 MARK_TS_TYPED (SIZEOF_EXPR); 450 MARK_TS_TYPED (ALIGNOF_EXPR); 451 MARK_TS_TYPED (AT_ENCODE_EXPR); 452 MARK_TS_TYPED (UNARY_PLUS_EXPR); 453 MARK_TS_TYPED (TRAIT_EXPR); 454 MARK_TS_TYPED (TYPE_ARGUMENT_PACK); 455 MARK_TS_TYPED (NOEXCEPT_EXPR); 456 MARK_TS_TYPED (NONTYPE_ARGUMENT_PACK); 457 MARK_TS_TYPED (WHILE_STMT); 458 MARK_TS_TYPED (NEW_EXPR); 459 MARK_TS_TYPED (VEC_NEW_EXPR); 460 MARK_TS_TYPED (BREAK_STMT); 461 MARK_TS_TYPED (MEMBER_REF); 462 MARK_TS_TYPED (DOTSTAR_EXPR); 463 MARK_TS_TYPED (DO_STMT); 464 MARK_TS_TYPED (DELETE_EXPR); 465 MARK_TS_TYPED (VEC_DELETE_EXPR); 466 MARK_TS_TYPED (CONTINUE_STMT); 467 MARK_TS_TYPED (TAG_DEFN); 468 MARK_TS_TYPED (PSEUDO_DTOR_EXPR); 469 MARK_TS_TYPED (TYPEID_EXPR); 470 MARK_TS_TYPED (MUST_NOT_THROW_EXPR); 471 MARK_TS_TYPED (STMT_EXPR); 472 MARK_TS_TYPED (OFFSET_REF); 473 MARK_TS_TYPED (OFFSETOF_EXPR); 474 MARK_TS_TYPED (ADDRESSOF_EXPR); 475 MARK_TS_TYPED (PTRMEM_CST); 476 MARK_TS_TYPED (EMPTY_CLASS_EXPR); 477 MARK_TS_TYPED (VEC_INIT_EXPR); 478 MARK_TS_TYPED (USING_STMT); 479 MARK_TS_TYPED (LAMBDA_EXPR); 480 MARK_TS_TYPED (CTOR_INITIALIZER); 481 MARK_TS_TYPED (REQUIRES_EXPR); 482 MARK_TS_TYPED (UNARY_LEFT_FOLD_EXPR); 483 MARK_TS_TYPED (UNARY_RIGHT_FOLD_EXPR); 484 MARK_TS_TYPED (BINARY_LEFT_FOLD_EXPR); 485 MARK_TS_TYPED (BINARY_RIGHT_FOLD_EXPR); 486 } 487 488 #include "gt-cp-cp-objcp-common.h" 489