1 /* Some code common to C++ and ObjC++ front ends. 2 Copyright (C) 2004-2019 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 || (INDIRECT_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 /* Return true if stmt can fall through. Used by block_may_fallthru 302 default case. */ 303 304 bool 305 cxx_block_may_fallthru (const_tree stmt) 306 { 307 switch (TREE_CODE (stmt)) 308 { 309 case EXPR_STMT: 310 return block_may_fallthru (EXPR_STMT_EXPR (stmt)); 311 312 case THROW_EXPR: 313 return false; 314 315 case IF_STMT: 316 if (block_may_fallthru (THEN_CLAUSE (stmt))) 317 return true; 318 return block_may_fallthru (ELSE_CLAUSE (stmt)); 319 320 case SWITCH_STMT: 321 return (!SWITCH_STMT_ALL_CASES_P (stmt) 322 || !SWITCH_STMT_NO_BREAK_P (stmt) 323 || block_may_fallthru (SWITCH_STMT_BODY (stmt))); 324 325 default: 326 return true; 327 } 328 } 329 330 /* Return the list of decls in the global namespace. */ 331 332 tree 333 cp_get_global_decls () 334 { 335 return NAMESPACE_LEVEL (global_namespace)->names; 336 } 337 338 /* Push DECL into the current scope. */ 339 340 tree 341 cp_pushdecl (tree decl) 342 { 343 return pushdecl (decl); 344 } 345 346 /* Get the global value binding of NAME. Called directly from 347 c-common.c, not via a hook. */ 348 349 tree 350 identifier_global_value (tree name) 351 { 352 return get_global_binding (name); 353 } 354 355 /* Similarly, but return struct/class/union NAME instead. */ 356 357 tree 358 identifier_global_tag (tree name) 359 { 360 tree ret = lookup_qualified_name (global_namespace, name, /*prefer_type*/2, 361 /*complain*/false); 362 if (ret == error_mark_node) 363 return NULL_TREE; 364 return ret; 365 } 366 367 /* Register c++-specific dumps. */ 368 369 void 370 cp_register_dumps (gcc::dump_manager *dumps) 371 { 372 class_dump_id = dumps->dump_register 373 (".class", "lang-class", "lang-class", DK_lang, OPTGROUP_NONE, false); 374 375 raw_dump_id = dumps->dump_register 376 (".raw", "lang-raw", "lang-raw", DK_lang, OPTGROUP_NONE, false); 377 } 378 379 void 380 cp_common_init_ts (void) 381 { 382 MARK_TS_DECL_NON_COMMON (USING_DECL); 383 MARK_TS_DECL_COMMON (TEMPLATE_DECL); 384 MARK_TS_DECL_COMMON (WILDCARD_DECL); 385 386 MARK_TS_COMMON (TEMPLATE_TEMPLATE_PARM); 387 MARK_TS_COMMON (TEMPLATE_TYPE_PARM); 388 MARK_TS_COMMON (TEMPLATE_PARM_INDEX); 389 MARK_TS_COMMON (OVERLOAD); 390 MARK_TS_COMMON (TEMPLATE_INFO); 391 MARK_TS_COMMON (TYPENAME_TYPE); 392 MARK_TS_COMMON (TYPEOF_TYPE); 393 MARK_TS_COMMON (UNDERLYING_TYPE); 394 MARK_TS_COMMON (BASELINK); 395 MARK_TS_COMMON (TYPE_PACK_EXPANSION); 396 MARK_TS_COMMON (TYPE_ARGUMENT_PACK); 397 MARK_TS_COMMON (DECLTYPE_TYPE); 398 MARK_TS_COMMON (BOUND_TEMPLATE_TEMPLATE_PARM); 399 MARK_TS_COMMON (UNBOUND_CLASS_TEMPLATE); 400 401 MARK_TS_TYPED (EXPR_PACK_EXPANSION); 402 MARK_TS_TYPED (SWITCH_STMT); 403 MARK_TS_TYPED (IF_STMT); 404 MARK_TS_TYPED (FOR_STMT); 405 MARK_TS_TYPED (RANGE_FOR_STMT); 406 MARK_TS_TYPED (AGGR_INIT_EXPR); 407 MARK_TS_TYPED (EXPR_STMT); 408 MARK_TS_TYPED (EH_SPEC_BLOCK); 409 MARK_TS_TYPED (CLEANUP_STMT); 410 MARK_TS_TYPED (SCOPE_REF); 411 MARK_TS_TYPED (CAST_EXPR); 412 MARK_TS_TYPED (NON_DEPENDENT_EXPR); 413 MARK_TS_TYPED (MODOP_EXPR); 414 MARK_TS_TYPED (TRY_BLOCK); 415 MARK_TS_TYPED (THROW_EXPR); 416 MARK_TS_TYPED (HANDLER); 417 MARK_TS_TYPED (REINTERPRET_CAST_EXPR); 418 MARK_TS_TYPED (CONST_CAST_EXPR); 419 MARK_TS_TYPED (STATIC_CAST_EXPR); 420 MARK_TS_TYPED (DYNAMIC_CAST_EXPR); 421 MARK_TS_TYPED (IMPLICIT_CONV_EXPR); 422 MARK_TS_TYPED (TEMPLATE_ID_EXPR); 423 MARK_TS_TYPED (ARROW_EXPR); 424 MARK_TS_TYPED (SIZEOF_EXPR); 425 MARK_TS_TYPED (ALIGNOF_EXPR); 426 MARK_TS_TYPED (AT_ENCODE_EXPR); 427 MARK_TS_TYPED (UNARY_PLUS_EXPR); 428 MARK_TS_TYPED (TRAIT_EXPR); 429 MARK_TS_TYPED (TYPE_ARGUMENT_PACK); 430 MARK_TS_TYPED (NOEXCEPT_EXPR); 431 MARK_TS_TYPED (NONTYPE_ARGUMENT_PACK); 432 MARK_TS_TYPED (WHILE_STMT); 433 MARK_TS_TYPED (NEW_EXPR); 434 MARK_TS_TYPED (VEC_NEW_EXPR); 435 MARK_TS_TYPED (BREAK_STMT); 436 MARK_TS_TYPED (MEMBER_REF); 437 MARK_TS_TYPED (DOTSTAR_EXPR); 438 MARK_TS_TYPED (DO_STMT); 439 MARK_TS_TYPED (DELETE_EXPR); 440 MARK_TS_TYPED (VEC_DELETE_EXPR); 441 MARK_TS_TYPED (CONTINUE_STMT); 442 MARK_TS_TYPED (TAG_DEFN); 443 MARK_TS_TYPED (PSEUDO_DTOR_EXPR); 444 MARK_TS_TYPED (TYPEID_EXPR); 445 MARK_TS_TYPED (MUST_NOT_THROW_EXPR); 446 MARK_TS_TYPED (STMT_EXPR); 447 MARK_TS_TYPED (OFFSET_REF); 448 MARK_TS_TYPED (OFFSETOF_EXPR); 449 MARK_TS_TYPED (ADDRESSOF_EXPR); 450 MARK_TS_TYPED (PTRMEM_CST); 451 MARK_TS_TYPED (EMPTY_CLASS_EXPR); 452 MARK_TS_TYPED (VEC_INIT_EXPR); 453 MARK_TS_TYPED (USING_STMT); 454 MARK_TS_TYPED (LAMBDA_EXPR); 455 MARK_TS_TYPED (CTOR_INITIALIZER); 456 MARK_TS_TYPED (REQUIRES_EXPR); 457 MARK_TS_TYPED (UNARY_LEFT_FOLD_EXPR); 458 MARK_TS_TYPED (UNARY_RIGHT_FOLD_EXPR); 459 MARK_TS_TYPED (BINARY_LEFT_FOLD_EXPR); 460 MARK_TS_TYPED (BINARY_RIGHT_FOLD_EXPR); 461 MARK_TS_TYPED (OMP_DEPOBJ); 462 } 463 464 #include "gt-cp-cp-objcp-common.h" 465