1/* Some code common to C++ and ObjC++ front ends.
2 Copyright (C) 2004-2017 Free Software Foundation, Inc.
3 Contributed by Ziemowit Laski <zlaski@apple.com>
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it under
8the terms of the GNU General Public License as published by the Free
9Software Foundation; either version 3, or (at your option) any later
10version.
11
12GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13WARRANTY; without even the implied warranty of MERCHANTABILITY or
14FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15for more details.
16
17You should have received a copy of the GNU General Public License
18along 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
30alias_set_type
31cxx_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
49bool
50cxx_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. */
61size_t
62cp_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
101bool
102cp_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
119int
120cxx_types_compatible_p (tree x, tree y)
121{
122 return same_type_ignoring_top_level_qualifiers_p (x, y);
123}
124
125static 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
130tree
131cp_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. */
160int
161cp_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. */
242int
243cp_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
275tree
276cp_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. */
284void
285push_file_scope (void)
286{
287}
288
289void
290pop_file_scope (void)
291{
292}
293
294/* c-pragma.c needs to query whether a decl has extern "C" linkage. */
295bool
296has_c_linkage (const_tree decl)
297{
298 return DECL_EXTERN_C_P (decl);
299}
300
301static 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
306tree
307decl_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
320void
321decl_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
331void
332init_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
341bool
342cxx_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 SWITCH_STMT:
353 return (!SWITCH_STMT_ALL_CASES_P (stmt)
354 || !SWITCH_STMT_NO_BREAK_P (stmt)
355 || block_may_fallthru (SWITCH_STMT_BODY (stmt)));
356
357 default:
358 return true;
359 }
360}
361
362/* Return the list of decls in the global namespace. */
363
364tree
365cp_get_global_decls ()
366{
367 return NAMESPACE_LEVEL (global_namespace)->names;
368}
369
370/* Push DECL into the current scope. */
371
372tree
373cp_pushdecl (tree decl)
374{
375 return pushdecl (decl);
376}
377
378/* Get the global value binding of NAME. Called directly from
379 c-common.c, not via a hook. */
380
381tree
382identifier_global_value (tree name)
383{
384 return get_global_binding (name);
385}
386
387/* Register c++-specific dumps. */
388
389void
390cp_register_dumps (gcc::dump_manager *dumps)
391{
392 class_dump_id = dumps->dump_register
393 (".class", "lang-class", "lang-class", DK_lang, OPTGROUP_NONE, false);
394
395 raw_dump_id = dumps->dump_register
396 (".raw", "lang-raw", "lang-raw", DK_lang, OPTGROUP_NONE, false);
397}
398
399void
400cp_common_init_ts (void)
401{
402 MARK_TS_DECL_NON_COMMON (USING_DECL);
403 MARK_TS_DECL_COMMON (TEMPLATE_DECL);
404 MARK_TS_DECL_COMMON (WILDCARD_DECL);
405
406 MARK_TS_COMMON (TEMPLATE_TEMPLATE_PARM);
407 MARK_TS_COMMON (TEMPLATE_TYPE_PARM);
408 MARK_TS_COMMON (TEMPLATE_PARM_INDEX);
409 MARK_TS_COMMON (OVERLOAD);
410 MARK_TS_COMMON (TEMPLATE_INFO);
411 MARK_TS_COMMON (TYPENAME_TYPE);
412 MARK_TS_COMMON (TYPEOF_TYPE);
413 MARK_TS_COMMON (UNDERLYING_TYPE);
414 MARK_TS_COMMON (BASELINK);
415 MARK_TS_COMMON (TYPE_PACK_EXPANSION);
416 MARK_TS_COMMON (TYPE_ARGUMENT_PACK);
417 MARK_TS_COMMON (DECLTYPE_TYPE);
418 MARK_TS_COMMON (BOUND_TEMPLATE_TEMPLATE_PARM);
419 MARK_TS_COMMON (UNBOUND_CLASS_TEMPLATE);
420
421 MARK_TS_TYPED (EXPR_PACK_EXPANSION);
422 MARK_TS_TYPED (SWITCH_STMT);
423 MARK_TS_TYPED (IF_STMT);
424 MARK_TS_TYPED (FOR_STMT);
425 MARK_TS_TYPED (RANGE_FOR_STMT);
426 MARK_TS_TYPED (AGGR_INIT_EXPR);
427 MARK_TS_TYPED (EXPR_STMT);
428 MARK_TS_TYPED (EH_SPEC_BLOCK);
429 MARK_TS_TYPED (CLEANUP_STMT);
430 MARK_TS_TYPED (SCOPE_REF);
431 MARK_TS_TYPED (CAST_EXPR);
432 MARK_TS_TYPED (NON_DEPENDENT_EXPR);
433 MARK_TS_TYPED (MODOP_EXPR);
434 MARK_TS_TYPED (TRY_BLOCK);
435 MARK_TS_TYPED (THROW_EXPR);
436 MARK_TS_TYPED (HANDLER);
437 MARK_TS_TYPED (REINTERPRET_CAST_EXPR);
438 MARK_TS_TYPED (CONST_CAST_EXPR);
439 MARK_TS_TYPED (STATIC_CAST_EXPR);
440 MARK_TS_TYPED (DYNAMIC_CAST_EXPR);
441 MARK_TS_TYPED (IMPLICIT_CONV_EXPR);
442 MARK_TS_TYPED (TEMPLATE_ID_EXPR);
443 MARK_TS_TYPED (ARROW_EXPR);
444 MARK_TS_TYPED (SIZEOF_EXPR);
445 MARK_TS_TYPED (ALIGNOF_EXPR);
446 MARK_TS_TYPED (AT_ENCODE_EXPR);
447 MARK_TS_TYPED (UNARY_PLUS_EXPR);
448 MARK_TS_TYPED (TRAIT_EXPR);
449 MARK_TS_TYPED (TYPE_ARGUMENT_PACK);
450 MARK_TS_TYPED (NOEXCEPT_EXPR);
451 MARK_TS_TYPED (NONTYPE_ARGUMENT_PACK);
452 MARK_TS_TYPED (WHILE_STMT);
453 MARK_TS_TYPED (NEW_EXPR);
454 MARK_TS_TYPED (VEC_NEW_EXPR);
455 MARK_TS_TYPED (BREAK_STMT);
456 MARK_TS_TYPED (MEMBER_REF);
457 MARK_TS_TYPED (DOTSTAR_EXPR);
458 MARK_TS_TYPED (DO_STMT);
459 MARK_TS_TYPED (DELETE_EXPR);
460 MARK_TS_TYPED (VEC_DELETE_EXPR);
461 MARK_TS_TYPED (CONTINUE_STMT);
462 MARK_TS_TYPED (TAG_DEFN);
463 MARK_TS_TYPED (PSEUDO_DTOR_EXPR);
464 MARK_TS_TYPED (TYPEID_EXPR);
465 MARK_TS_TYPED (MUST_NOT_THROW_EXPR);
466 MARK_TS_TYPED (STMT_EXPR);
467 MARK_TS_TYPED (OFFSET_REF);
468 MARK_TS_TYPED (OFFSETOF_EXPR);
469 MARK_TS_TYPED (ADDRESSOF_EXPR);
470 MARK_TS_TYPED (PTRMEM_CST);
471 MARK_TS_TYPED (EMPTY_CLASS_EXPR);
472 MARK_TS_TYPED (VEC_INIT_EXPR);
473 MARK_TS_TYPED (USING_STMT);
474 MARK_TS_TYPED (LAMBDA_EXPR);
475 MARK_TS_TYPED (CTOR_INITIALIZER);
476 MARK_TS_TYPED (REQUIRES_EXPR);
477 MARK_TS_TYPED (UNARY_LEFT_FOLD_EXPR);
478 MARK_TS_TYPED (UNARY_RIGHT_FOLD_EXPR);
479 MARK_TS_TYPED (BINARY_LEFT_FOLD_EXPR);
480 MARK_TS_TYPED (BINARY_RIGHT_FOLD_EXPR);
481}
482
483#include "gt-cp-cp-objcp-common.h"
484