1 /* Some code common to C++ and ObjC++ front ends.
2 Copyright (C) 2004-2020 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 #include "stringpool.h"
28
29 /* Special routine to get the alias set for C++. */
30
31 alias_set_type
cxx_get_alias_set(tree t)32 cxx_get_alias_set (tree t)
33 {
34 if (IS_FAKE_BASE_TYPE (t))
35 /* The base variant of a type must be in the same alias set as the
36 complete type. */
37 return get_alias_set (TYPE_CONTEXT (t));
38
39 /* Punt on PMFs until we canonicalize functions properly. */
40 if (TYPE_PTRMEMFUNC_P (t)
41 || (INDIRECT_TYPE_P (t)
42 && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))))
43 return 0;
44
45 return c_common_get_alias_set (t);
46 }
47
48 /* Called from check_global_declaration. */
49
50 bool
cxx_warn_unused_global_decl(const_tree decl)51 cxx_warn_unused_global_decl (const_tree decl)
52 {
53 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl))
54 return false;
55 if (DECL_IN_SYSTEM_HEADER (decl))
56 return false;
57
58 return true;
59 }
60
61 /* Langhook for tree_size: determine size of our 'x' and 'c' nodes. */
62 size_t
cp_tree_size(enum tree_code code)63 cp_tree_size (enum tree_code code)
64 {
65 gcc_checking_assert (code >= NUM_TREE_CODES);
66 switch (code)
67 {
68 case PTRMEM_CST: return sizeof (ptrmem_cst);
69 case BASELINK: return sizeof (tree_baselink);
70 case TEMPLATE_PARM_INDEX: return sizeof (template_parm_index);
71 case DEFERRED_PARSE: return sizeof (tree_deferred_parse);
72 case DEFERRED_NOEXCEPT: return sizeof (tree_deferred_noexcept);
73 case OVERLOAD: return sizeof (tree_overload);
74 case STATIC_ASSERT: return sizeof (tree_static_assert);
75 case TYPE_ARGUMENT_PACK:
76 case TYPE_PACK_EXPANSION: return sizeof (tree_type_non_common);
77 case NONTYPE_ARGUMENT_PACK:
78 case EXPR_PACK_EXPANSION: return sizeof (tree_exp);
79 case ARGUMENT_PACK_SELECT: return sizeof (tree_argument_pack_select);
80 case TRAIT_EXPR: return sizeof (tree_trait_expr);
81 case LAMBDA_EXPR: return sizeof (tree_lambda_expr);
82 case TEMPLATE_INFO: return sizeof (tree_template_info);
83 case CONSTRAINT_INFO: return sizeof (tree_constraint_info);
84 case USERDEF_LITERAL: return sizeof (tree_userdef_literal);
85 case TEMPLATE_DECL: return sizeof (tree_template_decl);
86 default:
87 switch (TREE_CODE_CLASS (code))
88 {
89 case tcc_declaration: return sizeof (tree_decl_non_common);
90 case tcc_type: return sizeof (tree_type_non_common);
91 default: gcc_unreachable ();
92 }
93 }
94 /* NOTREACHED */
95 }
96
97 /* Returns true if T is a variably modified type, in the sense of C99.
98 FN is as passed to variably_modified_p.
99 This routine needs only check cases that cannot be handled by the
100 language-independent logic in tree.c. */
101
102 bool
cp_var_mod_type_p(tree type,tree fn)103 cp_var_mod_type_p (tree type, tree fn)
104 {
105 /* If TYPE is a pointer-to-member, it is variably modified if either
106 the class or the member are variably modified. */
107 if (TYPE_PTRMEM_P (type))
108 return (variably_modified_type_p (TYPE_PTRMEM_CLASS_TYPE (type), fn)
109 || variably_modified_type_p (TYPE_PTRMEM_POINTED_TO_TYPE (type),
110 fn));
111
112 /* All other types are not variably modified. */
113 return false;
114 }
115
116 /* This compares two types for equivalence ("compatible" in C-based languages).
117 This routine should only return 1 if it is sure. It should not be used
118 in contexts where erroneously returning 0 causes problems. */
119
120 int
cxx_types_compatible_p(tree x,tree y)121 cxx_types_compatible_p (tree x, tree y)
122 {
123 return same_type_ignoring_top_level_qualifiers_p (x, y);
124 }
125
126 static GTY((cache)) type_tree_cache_map *debug_type_map;
127
128 /* Return a type to use in the debug info instead of TYPE, or NULL_TREE to
129 keep TYPE. */
130
131 tree
cp_get_debug_type(const_tree type)132 cp_get_debug_type (const_tree type)
133 {
134 tree dtype = NULL_TREE;
135
136 if (TYPE_PTRMEMFUNC_P (type) && !typedef_variant_p (type))
137 dtype = build_offset_type (TYPE_PTRMEMFUNC_OBJECT_TYPE (type),
138 TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (type)));
139
140 /* We cannot simply return the debug type here because the function uses
141 the type canonicalization hashtable, which is GC-ed, so its behavior
142 depends on the actual collection points. Since we are building these
143 types on the fly for the debug info only, they would not be attached
144 to any GC root and always be swept, so we would make the contents of
145 the debug info depend on the collection points. */
146 if (dtype)
147 {
148 tree ktype = CONST_CAST_TREE (type);
149 if (tree *slot = hash_map_safe_get (debug_type_map, ktype))
150 return *slot;
151 hash_map_safe_put<hm_ggc> (debug_type_map, ktype, dtype);
152 }
153
154 return dtype;
155 }
156
157 /* Return -1 if dwarf ATTR shouldn't be added for DECL, or the attribute
158 value otherwise. */
159 int
cp_decl_dwarf_attribute(const_tree decl,int attr)160 cp_decl_dwarf_attribute (const_tree decl, int attr)
161 {
162 if (decl == NULL_TREE)
163 return -1;
164
165 switch (attr)
166 {
167 case DW_AT_explicit:
168 if (TREE_CODE (decl) == FUNCTION_DECL
169 && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl))
170 && DECL_NONCONVERTING_P (decl))
171 return 1;
172 break;
173
174 case DW_AT_deleted:
175 if (TREE_CODE (decl) == FUNCTION_DECL
176 && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl))
177 && DECL_DELETED_FN (decl))
178 return 1;
179 break;
180
181 case DW_AT_defaulted:
182 if (TREE_CODE (decl) == FUNCTION_DECL
183 && DECL_LANG_SPECIFIC (STRIP_TEMPLATE (decl))
184 && DECL_DEFAULTED_FN (decl))
185 {
186 if (DECL_DEFAULTED_IN_CLASS_P (decl))
187 return DW_DEFAULTED_in_class;
188
189 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (decl))
190 return DW_DEFAULTED_out_of_class;
191 }
192 break;
193
194 case DW_AT_const_expr:
195 if (VAR_OR_FUNCTION_DECL_P (decl) && DECL_DECLARED_CONSTEXPR_P (decl))
196 return 1;
197 break;
198
199 case DW_AT_reference:
200 if (TREE_CODE (decl) == FUNCTION_DECL
201 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)
202 && FUNCTION_REF_QUALIFIED (TREE_TYPE (decl))
203 && !FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (decl)))
204 return 1;
205 break;
206
207 case DW_AT_rvalue_reference:
208 if (TREE_CODE (decl) == FUNCTION_DECL
209 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)
210 && FUNCTION_REF_QUALIFIED (TREE_TYPE (decl))
211 && FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (decl)))
212 return 1;
213 break;
214
215 case DW_AT_inline:
216 if (VAR_P (decl) && DECL_INLINE_VAR_P (decl))
217 {
218 if (DECL_VAR_DECLARED_INLINE_P (decl))
219 return DW_INL_declared_inlined;
220 else
221 return DW_INL_inlined;
222 }
223 break;
224
225 case DW_AT_export_symbols:
226 if (TREE_CODE (decl) == NAMESPACE_DECL
227 && (DECL_NAMESPACE_INLINE_P (decl)
228 || (DECL_NAME (decl) == NULL_TREE && dwarf_version >= 5)))
229 return 1;
230 break;
231
232 default:
233 break;
234 }
235
236 return -1;
237 }
238
239 /* Return -1 if dwarf ATTR shouldn't be added for TYPE, or the attribute
240 value otherwise. */
241 int
cp_type_dwarf_attribute(const_tree type,int attr)242 cp_type_dwarf_attribute (const_tree type, int attr)
243 {
244 if (type == NULL_TREE)
245 return -1;
246
247 switch (attr)
248 {
249 case DW_AT_reference:
250 if (FUNC_OR_METHOD_TYPE_P (type)
251 && FUNCTION_REF_QUALIFIED (type)
252 && !FUNCTION_RVALUE_QUALIFIED (type))
253 return 1;
254 break;
255
256 case DW_AT_rvalue_reference:
257 if (FUNC_OR_METHOD_TYPE_P (type)
258 && FUNCTION_REF_QUALIFIED (type)
259 && FUNCTION_RVALUE_QUALIFIED (type))
260 return 1;
261 break;
262
263 default:
264 break;
265 }
266
267 return -1;
268 }
269
270 /* Return the unit size of TYPE without reusable tail padding. */
271
272 tree
cp_unit_size_without_reusable_padding(tree type)273 cp_unit_size_without_reusable_padding (tree type)
274 {
275 if (CLASS_TYPE_P (type))
276 return CLASSTYPE_SIZE_UNIT (type);
277 return TYPE_SIZE_UNIT (type);
278 }
279
280 /* Stubs to keep c-opts.c happy. */
281 void
push_file_scope(void)282 push_file_scope (void)
283 {
284 }
285
286 void
pop_file_scope(void)287 pop_file_scope (void)
288 {
289 }
290
291 /* c-pragma.c needs to query whether a decl has extern "C" linkage. */
292 bool
has_c_linkage(const_tree decl)293 has_c_linkage (const_tree decl)
294 {
295 return DECL_EXTERN_C_P (decl);
296 }
297
298 /* Return true if stmt can fall through. Used by block_may_fallthru
299 default case. */
300
301 bool
cxx_block_may_fallthru(const_tree stmt)302 cxx_block_may_fallthru (const_tree stmt)
303 {
304 switch (TREE_CODE (stmt))
305 {
306 case EXPR_STMT:
307 return block_may_fallthru (EXPR_STMT_EXPR (stmt));
308
309 case THROW_EXPR:
310 return false;
311
312 case IF_STMT:
313 if (block_may_fallthru (THEN_CLAUSE (stmt)))
314 return true;
315 return block_may_fallthru (ELSE_CLAUSE (stmt));
316
317 case SWITCH_STMT:
318 return (!SWITCH_STMT_ALL_CASES_P (stmt)
319 || !SWITCH_STMT_NO_BREAK_P (stmt)
320 || block_may_fallthru (SWITCH_STMT_BODY (stmt)));
321
322 default:
323 return true;
324 }
325 }
326
327 /* Return the list of decls in the global namespace. */
328
329 tree
cp_get_global_decls()330 cp_get_global_decls ()
331 {
332 return NAMESPACE_LEVEL (global_namespace)->names;
333 }
334
335 /* Push DECL into the current scope. */
336
337 tree
cp_pushdecl(tree decl)338 cp_pushdecl (tree decl)
339 {
340 return pushdecl (decl);
341 }
342
343 /* Get the global value binding of NAME. Called directly from
344 c-common.c, not via a hook. */
345
346 tree
identifier_global_value(tree name)347 identifier_global_value (tree name)
348 {
349 return get_global_binding (name);
350 }
351
352 /* Similarly, but return struct/class/union NAME instead. */
353
354 tree
identifier_global_tag(tree name)355 identifier_global_tag (tree name)
356 {
357 tree ret = lookup_qualified_name (global_namespace, name, /*prefer_type*/2,
358 /*complain*/false);
359 if (ret == error_mark_node)
360 return NULL_TREE;
361 return ret;
362 }
363
364 /* Returns true if NAME refers to a built-in function or function-like
365 operator. */
366
367 bool
names_builtin_p(const char * name)368 names_builtin_p (const char *name)
369 {
370 tree id = get_identifier (name);
371 if (tree binding = get_global_binding (id))
372 {
373 if (TREE_CODE (binding) == FUNCTION_DECL && DECL_IS_BUILTIN (binding))
374 return true;
375
376 /* Handle the case when an overload for a built-in name exists. */
377 if (TREE_CODE (binding) != OVERLOAD)
378 return false;
379
380 for (ovl_iterator it (binding); it; ++it)
381 {
382 tree decl = *it;
383 if (DECL_IS_BUILTIN (decl))
384 return true;
385 }
386 }
387
388 /* Also detect common reserved C++ words that aren't strictly built-in
389 functions. */
390 switch (C_RID_CODE (id))
391 {
392 case RID_ADDRESSOF:
393 case RID_BUILTIN_CONVERTVECTOR:
394 case RID_BUILTIN_HAS_ATTRIBUTE:
395 case RID_BUILTIN_SHUFFLE:
396 case RID_BUILTIN_LAUNDER:
397 case RID_OFFSETOF:
398 case RID_HAS_NOTHROW_ASSIGN:
399 case RID_HAS_NOTHROW_CONSTRUCTOR:
400 case RID_HAS_NOTHROW_COPY:
401 case RID_HAS_TRIVIAL_ASSIGN:
402 case RID_HAS_TRIVIAL_CONSTRUCTOR:
403 case RID_HAS_TRIVIAL_COPY:
404 case RID_HAS_TRIVIAL_DESTRUCTOR:
405 case RID_HAS_UNIQUE_OBJ_REPRESENTATIONS:
406 case RID_HAS_VIRTUAL_DESTRUCTOR:
407 case RID_IS_ABSTRACT:
408 case RID_IS_AGGREGATE:
409 case RID_IS_BASE_OF:
410 case RID_IS_CLASS:
411 case RID_IS_EMPTY:
412 case RID_IS_ENUM:
413 case RID_IS_FINAL:
414 case RID_IS_LITERAL_TYPE:
415 case RID_IS_POD:
416 case RID_IS_POLYMORPHIC:
417 case RID_IS_SAME_AS:
418 case RID_IS_STD_LAYOUT:
419 case RID_IS_TRIVIAL:
420 case RID_IS_TRIVIALLY_ASSIGNABLE:
421 case RID_IS_TRIVIALLY_CONSTRUCTIBLE:
422 case RID_IS_TRIVIALLY_COPYABLE:
423 case RID_IS_UNION:
424 case RID_IS_ASSIGNABLE:
425 case RID_IS_CONSTRUCTIBLE:
426 case RID_UNDERLYING_TYPE:
427 return true;
428 default:
429 break;
430 }
431
432 return false;
433 }
434
435 /* Register c++-specific dumps. */
436
437 void
cp_register_dumps(gcc::dump_manager * dumps)438 cp_register_dumps (gcc::dump_manager *dumps)
439 {
440 class_dump_id = dumps->dump_register
441 (".class", "lang-class", "lang-class", DK_lang, OPTGROUP_NONE, false);
442
443 raw_dump_id = dumps->dump_register
444 (".raw", "lang-raw", "lang-raw", DK_lang, OPTGROUP_NONE, false);
445 }
446
447 void
cp_common_init_ts(void)448 cp_common_init_ts (void)
449 {
450 /* With type. */
451 MARK_TS_TYPED (PTRMEM_CST);
452 MARK_TS_TYPED (LAMBDA_EXPR);
453 MARK_TS_TYPED (TYPE_ARGUMENT_PACK);
454
455 /* Random new trees. */
456 MARK_TS_COMMON (BASELINK);
457 MARK_TS_COMMON (DECLTYPE_TYPE);
458 MARK_TS_COMMON (OVERLOAD);
459 MARK_TS_COMMON (TEMPLATE_PARM_INDEX);
460 MARK_TS_COMMON (TYPENAME_TYPE);
461 MARK_TS_COMMON (TYPEOF_TYPE);
462 MARK_TS_COMMON (UNBOUND_CLASS_TEMPLATE);
463 MARK_TS_COMMON (UNDERLYING_TYPE);
464
465 /* New decls. */
466 MARK_TS_DECL_COMMON (TEMPLATE_DECL);
467 MARK_TS_DECL_COMMON (WILDCARD_DECL);
468 MARK_TS_DECL_COMMON (CONCEPT_DECL);
469
470 MARK_TS_DECL_NON_COMMON (USING_DECL);
471
472 /* New Types. */
473 MARK_TS_TYPE_NON_COMMON (BOUND_TEMPLATE_TEMPLATE_PARM);
474 MARK_TS_TYPE_NON_COMMON (TEMPLATE_TEMPLATE_PARM);
475 MARK_TS_TYPE_NON_COMMON (TEMPLATE_TYPE_PARM);
476 MARK_TS_TYPE_NON_COMMON (TYPE_ARGUMENT_PACK);
477 MARK_TS_TYPE_NON_COMMON (TYPE_PACK_EXPANSION);
478
479 /* Statements. */
480 MARK_TS_EXP (BREAK_STMT);
481 MARK_TS_EXP (CLEANUP_STMT);
482 MARK_TS_EXP (CONTINUE_STMT);
483 MARK_TS_EXP (DO_STMT);
484 MARK_TS_EXP (EH_SPEC_BLOCK);
485 MARK_TS_EXP (FOR_STMT);
486 MARK_TS_EXP (HANDLER);
487 MARK_TS_EXP (IF_STMT);
488 MARK_TS_EXP (OMP_DEPOBJ);
489 MARK_TS_EXP (RANGE_FOR_STMT);
490 MARK_TS_EXP (SWITCH_STMT);
491 MARK_TS_EXP (TRY_BLOCK);
492 MARK_TS_EXP (USING_STMT);
493 MARK_TS_EXP (WHILE_STMT);
494
495 /* Random expressions. */
496 MARK_TS_EXP (ADDRESSOF_EXPR);
497 MARK_TS_EXP (AGGR_INIT_EXPR);
498 MARK_TS_EXP (ALIGNOF_EXPR);
499 MARK_TS_EXP (ARROW_EXPR);
500 MARK_TS_EXP (AT_ENCODE_EXPR);
501 MARK_TS_EXP (CAST_EXPR);
502 MARK_TS_EXP (CONST_CAST_EXPR);
503 MARK_TS_EXP (CTOR_INITIALIZER);
504 MARK_TS_EXP (DELETE_EXPR);
505 MARK_TS_EXP (DOTSTAR_EXPR);
506 MARK_TS_EXP (DYNAMIC_CAST_EXPR);
507 MARK_TS_EXP (EMPTY_CLASS_EXPR);
508 MARK_TS_EXP (EXPR_STMT);
509 MARK_TS_EXP (IMPLICIT_CONV_EXPR);
510 MARK_TS_EXP (MEMBER_REF);
511 MARK_TS_EXP (MODOP_EXPR);
512 MARK_TS_EXP (MUST_NOT_THROW_EXPR);
513 MARK_TS_EXP (NEW_EXPR);
514 MARK_TS_EXP (NOEXCEPT_EXPR);
515 MARK_TS_EXP (NON_DEPENDENT_EXPR);
516 MARK_TS_EXP (OFFSETOF_EXPR);
517 MARK_TS_EXP (OFFSET_REF);
518 MARK_TS_EXP (PSEUDO_DTOR_EXPR);
519 MARK_TS_EXP (REINTERPRET_CAST_EXPR);
520 MARK_TS_EXP (SCOPE_REF);
521 MARK_TS_EXP (STATIC_CAST_EXPR);
522 MARK_TS_EXP (STMT_EXPR);
523 MARK_TS_EXP (TAG_DEFN);
524 MARK_TS_EXP (TEMPLATE_ID_EXPR);
525 MARK_TS_EXP (THROW_EXPR);
526 MARK_TS_EXP (TRAIT_EXPR);
527 MARK_TS_EXP (TYPEID_EXPR);
528 MARK_TS_EXP (TYPE_EXPR);
529 MARK_TS_EXP (UNARY_PLUS_EXPR);
530 MARK_TS_EXP (VEC_DELETE_EXPR);
531 MARK_TS_EXP (VEC_INIT_EXPR);
532 MARK_TS_EXP (VEC_NEW_EXPR);
533 MARK_TS_EXP (SPACESHIP_EXPR);
534
535 /* Fold expressions. */
536 MARK_TS_EXP (BINARY_LEFT_FOLD_EXPR);
537 MARK_TS_EXP (BINARY_RIGHT_FOLD_EXPR);
538 MARK_TS_EXP (EXPR_PACK_EXPANSION);
539 MARK_TS_EXP (NONTYPE_ARGUMENT_PACK);
540 MARK_TS_EXP (UNARY_LEFT_FOLD_EXPR);
541 MARK_TS_EXP (UNARY_RIGHT_FOLD_EXPR);
542
543 /* Constraints. */
544 MARK_TS_EXP (CHECK_CONSTR);
545 MARK_TS_EXP (COMPOUND_REQ);
546 MARK_TS_EXP (CONJ_CONSTR);
547 MARK_TS_EXP (DISJ_CONSTR);
548 MARK_TS_EXP (ATOMIC_CONSTR);
549 MARK_TS_EXP (NESTED_REQ);
550 MARK_TS_EXP (REQUIRES_EXPR);
551 MARK_TS_EXP (SIMPLE_REQ);
552 MARK_TS_EXP (TYPE_REQ);
553
554 MARK_TS_EXP (CO_AWAIT_EXPR);
555 MARK_TS_EXP (CO_YIELD_EXPR);
556 MARK_TS_EXP (CO_RETURN_EXPR);
557
558 c_common_init_ts ();
559 }
560
561 #include "gt-cp-cp-objcp-common.h"
562