1 | /* RunTime Type Identification |
---|---|
2 | Copyright (C) 1995-2025 Free Software Foundation, Inc. |
3 | Mostly written by Jason Merrill (jason@cygnus.com). |
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 | #include "config.h" |
22 | #include "system.h" |
23 | #include "coretypes.h" |
24 | #include "target.h" |
25 | #include "cp-tree.h" |
26 | #include "memmodel.h" |
27 | #include "tm_p.h" |
28 | #include "stringpool.h" |
29 | #include "intl.h" |
30 | #include "stor-layout.h" |
31 | #include "c-family/c-pragma.h" |
32 | #include "gcc-rich-location.h" |
33 | |
34 | /* C++ returns type information to the user in struct type_info |
35 | objects. We also use type information to implement dynamic_cast and |
36 | exception handlers. Type information for a particular type is |
37 | indicated with an ABI defined structure derived from type_info. |
38 | This would all be very straight forward, but for the fact that the |
39 | runtime library provides the definitions of the type_info structure |
40 | and the ABI defined derived classes. We cannot build declarations |
41 | of them directly in the compiler, but we need to layout objects of |
42 | their type. Somewhere we have to lie. |
43 | |
44 | We define layout compatible POD-structs with compiler-defined names |
45 | and generate the appropriate initializations for them (complete |
46 | with explicit mention of their vtable). When we have to provide a |
47 | type_info to the user we reinterpret_cast the internal compiler |
48 | type to type_info. A well formed program can only explicitly refer |
49 | to the type_infos of complete types (& cv void). However, we chain |
50 | pointer type_infos to the pointed-to-type, and that can be |
51 | incomplete. We only need the addresses of such incomplete |
52 | type_info objects for static initialization. |
53 | |
54 | The type information VAR_DECL of a type is held on the |
55 | get_global_binding of the type's mangled name. That VAR_DECL |
56 | will be the internal type. It will usually have the correct |
57 | internal type reflecting the kind of type it represents (pointer, |
58 | array, function, class, inherited class, etc). When the type it |
59 | represents is incomplete, it will have the internal type |
60 | corresponding to type_info. That will only happen at the end of |
61 | translation, when we are emitting the type info objects. */ |
62 | |
63 | /* Auxiliary data we hold for each type_info derived object we need. */ |
64 | struct GTY (()) tinfo_s { |
65 | tree type; /* The (const-qualified) RECORD_TYPE for this type_info object */ |
66 | |
67 | tree vtable; /* The VAR_DECL of the vtable. Only filled at end of |
68 | translation. */ |
69 | |
70 | tree name; /* IDENTIFIER_NODE for the ABI specified name of |
71 | the type_info derived type. */ |
72 | }; |
73 | |
74 | |
75 | enum tinfo_kind |
76 | { |
77 | TK_TYPE_INFO_TYPE, /* abi::__type_info_pseudo */ |
78 | TK_BASE_TYPE, /* abi::__base_class_type_info */ |
79 | TK_DERIVED_TYPES, /* Start of types derived from abi::__type_info */ |
80 | TK_BUILTIN_TYPE = TK_DERIVED_TYPES, /* abi::__fundamental_type_info */ |
81 | TK_ARRAY_TYPE, /* abi::__array_type_info */ |
82 | TK_FUNCTION_TYPE, /* abi::__function_type_info */ |
83 | TK_ENUMERAL_TYPE, /* abi::__enum_type_info */ |
84 | TK_POINTER_TYPE, /* abi::__pointer_type_info */ |
85 | TK_POINTER_MEMBER_TYPE, /* abi::__pointer_to_member_type_info */ |
86 | TK_CLASS_TYPE, /* abi::__class_type_info */ |
87 | TK_SI_CLASS_TYPE, /* abi::__si_class_type_info */ |
88 | TK_VMI_CLASS_TYPES, /* abi::__vmi_class_type_info<int> */ |
89 | TK_MAX |
90 | }; |
91 | |
92 | /* Names of the tinfo types. Must be same order as TK enumeration |
93 | above. */ |
94 | |
95 | static const char *const tinfo_names[TK_MAX] = |
96 | { |
97 | "__type_info", |
98 | "__base_class_type_info", |
99 | "__fundamental_type_info", |
100 | "__array_type_info", |
101 | "__function_type_info", |
102 | "__enum_type_info", |
103 | "__pointer_type_info", |
104 | "__pointer_to_member_type_info", |
105 | "__class_type_info", |
106 | "__si_class_type_info", |
107 | "__vmi_class_type_info" |
108 | }; |
109 | |
110 | /* Helper macro to get maximum scalar-width of pointer or of the 'long'-type. |
111 | This of interest for llp64 targets. */ |
112 | #define LONGPTR_T \ |
113 | integer_types[(POINTER_SIZE <= TYPE_PRECISION (integer_types[itk_long]) \ |
114 | ? itk_long : itk_long_long)] |
115 | |
116 | /* A vector of all tinfo decls that haven't yet been emitted. */ |
117 | vec<tree, va_gc> *unemitted_tinfo_decls; |
118 | |
119 | /* A vector of all type_info derived types we need. The first few are |
120 | fixed and created early. The remainder are for multiple inheritance |
121 | and are generated as needed. */ |
122 | static GTY (()) vec<tinfo_s, va_gc> *tinfo_descs; |
123 | |
124 | static tree tinfo_name (tree, bool); |
125 | static tree build_dynamic_cast_1 (location_t, tree, tree, tsubst_flags_t); |
126 | static tree throw_bad_cast (void); |
127 | static tree throw_bad_typeid (void); |
128 | static bool typeid_ok_p (void); |
129 | static int qualifier_flags (tree); |
130 | static bool target_incomplete_p (tree); |
131 | static tree tinfo_base_init (tinfo_s *, tree); |
132 | static tree generic_initializer (tinfo_s *, tree); |
133 | static tree ptr_initializer (tinfo_s *, tree); |
134 | static tree ptm_initializer (tinfo_s *, tree); |
135 | static tree class_initializer (tinfo_s *, tree, unsigned, ...); |
136 | static tree get_pseudo_ti_init (tree, unsigned); |
137 | static unsigned get_pseudo_ti_index (tree); |
138 | static tinfo_s *get_tinfo_desc (unsigned); |
139 | static void create_tinfo_types (void); |
140 | static bool typeinfo_in_lib_p (tree); |
141 | |
142 | static int doing_runtime = 0; |
143 | |
144 | /* Create the internal versions of the ABI types. */ |
145 | |
146 | void |
147 | init_rtti_processing (void) |
148 | { |
149 | vec_alloc (v&: unemitted_tinfo_decls, nelems: 124); |
150 | |
151 | create_tinfo_types (); |
152 | } |
153 | |
154 | /* Given the expression EXP of type `class *', return the head of the |
155 | object pointed to by EXP with type cv void*, if the class has any |
156 | virtual functions (TYPE_POLYMORPHIC_P), else just return the |
157 | expression. */ |
158 | |
159 | tree |
160 | build_headof (tree exp) |
161 | { |
162 | tree type = TREE_TYPE (exp); |
163 | tree offset; |
164 | tree index; |
165 | |
166 | gcc_assert (TYPE_PTR_P (type)); |
167 | type = TREE_TYPE (type); |
168 | |
169 | if (!TYPE_POLYMORPHIC_P (type)) |
170 | return exp; |
171 | |
172 | /* We use this a couple of times below, protect it. */ |
173 | exp = save_expr (exp); |
174 | |
175 | /* The offset-to-top field is at index -2 from the vptr. */ |
176 | index = build_int_cst (NULL_TREE, |
177 | -2 * TARGET_VTABLE_DATA_ENTRY_DISTANCE); |
178 | |
179 | offset = build_vtbl_ref (cp_build_fold_indirect_ref (exp), |
180 | index); |
181 | |
182 | cp_build_qualified_type (ptr_type_node, |
183 | cp_type_quals (TREE_TYPE (exp))); |
184 | return fold_build_pointer_plus (exp, offset); |
185 | } |
186 | |
187 | /* Get a bad_cast node for the program to throw... |
188 | |
189 | See 'libstdc++-v3/libsupc++/eh_aux_runtime.cc' for '__cxa_bad_cast'. */ |
190 | |
191 | static tree |
192 | throw_bad_cast (void) |
193 | { |
194 | static tree fn; |
195 | if (!fn) |
196 | { |
197 | tree name = get_identifier ("__cxa_bad_cast"); |
198 | fn = get_global_binding (id: name); |
199 | if (!fn) |
200 | fn = push_throw_library_fn |
201 | (name, build_function_type_list (void_type_node, NULL_TREE)); |
202 | } |
203 | |
204 | return build_cxx_call (fn, 0, NULL, tf_warning_or_error); |
205 | } |
206 | |
207 | /* See 'libstdc++-v3/libsupc++/eh_aux_runtime.cc' for '__cxa_bad_typeid'. */ |
208 | |
209 | static tree |
210 | throw_bad_typeid (void) |
211 | { |
212 | static tree fn; |
213 | if (!fn) |
214 | { |
215 | tree name = get_identifier ("__cxa_bad_typeid"); |
216 | fn = get_global_binding (id: name); |
217 | if (!fn) |
218 | fn = push_throw_library_fn |
219 | (name, build_function_type_list (void_type_node, NULL_TREE)); |
220 | } |
221 | |
222 | return build_cxx_call (fn, 0, NULL, tf_warning_or_error); |
223 | } |
224 | |
225 | /* const type_info*. */ |
226 | |
227 | inline tree |
228 | type_info_ptr_type () |
229 | { |
230 | return build_pointer_type (const_type_info_type_node); |
231 | } |
232 | |
233 | /* Return a pointer to a type_info object describing TYPE, suitably |
234 | cast to the language defined type (for typeid) or void (for building |
235 | up the descriptors). */ |
236 | |
237 | static tree |
238 | get_tinfo_ptr (tree type, bool voidp = false) |
239 | { |
240 | tree decl = get_tinfo_decl (type); |
241 | mark_used (decl); |
242 | |
243 | tree ptype = voidp ? const_ptr_type_node : type_info_ptr_type (); |
244 | return build_nop (ptype, build_address (decl)); |
245 | } |
246 | static inline tree |
247 | get_void_tinfo_ptr (tree type) |
248 | { |
249 | return get_tinfo_ptr (type, voidp: true); |
250 | } |
251 | |
252 | /* Return an lvalue expression whose type is "const std::type_info" |
253 | and whose value indicates the type of the expression EXP. If EXP |
254 | is a reference to a polymorphic class, return the dynamic type; |
255 | otherwise return the static type of the expression. */ |
256 | |
257 | static tree |
258 | get_tinfo_ptr_dynamic (tree exp, tsubst_flags_t complain) |
259 | { |
260 | tree type; |
261 | tree t; |
262 | |
263 | if (error_operand_p (t: exp)) |
264 | return error_mark_node; |
265 | |
266 | exp = resolve_nondeduced_context (exp, complain); |
267 | |
268 | /* Peel back references, so they match. */ |
269 | type = non_reference (unlowered_expr_type (exp)); |
270 | |
271 | /* Peel off cv qualifiers. */ |
272 | type = cv_unqualified (type); |
273 | |
274 | /* For UNKNOWN_TYPEs call complete_type_or_else to get diagnostics. */ |
275 | if (CLASS_TYPE_P (type) || type == unknown_type_node |
276 | || type == init_list_type_node) |
277 | type = complete_type_or_maybe_complain (type, exp, complain); |
278 | |
279 | if (!type) |
280 | return error_mark_node; |
281 | |
282 | /* If exp is a reference to polymorphic type, get the real type_info. */ |
283 | if (TYPE_POLYMORPHIC_P (type) && ! resolves_to_fixed_type_p (exp, 0)) |
284 | { |
285 | /* build reference to type_info from vtable. */ |
286 | tree index; |
287 | |
288 | /* The RTTI information is at index -1. */ |
289 | index = build_int_cst (NULL_TREE, |
290 | -1 * TARGET_VTABLE_DATA_ENTRY_DISTANCE); |
291 | t = build_vtbl_ref (exp, index); |
292 | t = convert (type_info_ptr_type (), t); |
293 | } |
294 | else |
295 | /* Otherwise return the type_info for the static type of the expr. */ |
296 | t = get_tinfo_ptr (type); |
297 | |
298 | return t; |
299 | } |
300 | |
301 | static bool |
302 | typeid_ok_p (void) |
303 | { |
304 | if (! flag_rtti) |
305 | { |
306 | error ("cannot use %<typeid%> with %<-fno-rtti%>"); |
307 | return false; |
308 | } |
309 | |
310 | if (!const_type_info_type_node) |
311 | { |
312 | tree name = get_identifier ("type_info"); |
313 | tree decl = lookup_qualified_name (std_node, name); |
314 | if (TREE_CODE (decl) != TYPE_DECL) |
315 | { |
316 | gcc_rich_location richloc (input_location); |
317 | maybe_add_include_fixit (&richloc, "<typeinfo>", false); |
318 | error_at (&richloc, |
319 | "must %<#include <typeinfo>%> before using" |
320 | " %<typeid%>"); |
321 | |
322 | return false; |
323 | } |
324 | const_type_info_type_node |
325 | = cp_build_qualified_type (TREE_TYPE (decl), TYPE_QUAL_CONST); |
326 | } |
327 | |
328 | tree pseudo = TYPE_MAIN_VARIANT (get_tinfo_desc (TK_TYPE_INFO_TYPE)->type); |
329 | tree real = TYPE_MAIN_VARIANT (const_type_info_type_node); |
330 | |
331 | /* Make sure abi::__type_info_pseudo has the same alias set |
332 | as std::type_info. */ |
333 | if (! TYPE_ALIAS_SET_KNOWN_P (pseudo)) |
334 | TYPE_ALIAS_SET (pseudo) = get_alias_set (real); |
335 | else |
336 | gcc_assert (TYPE_ALIAS_SET (pseudo) == get_alias_set (real)); |
337 | |
338 | return true; |
339 | } |
340 | |
341 | /* Return an expression for "typeid(EXP)". The expression returned is |
342 | an lvalue of type "const std::type_info". */ |
343 | |
344 | tree |
345 | build_typeid (tree exp, tsubst_flags_t complain) |
346 | { |
347 | tree cond = NULL_TREE, initial_expr = exp; |
348 | int nonnull = 0; |
349 | |
350 | if (exp == error_mark_node || !typeid_ok_p ()) |
351 | return error_mark_node; |
352 | |
353 | if (processing_template_decl) |
354 | return build_min (TYPEID_EXPR, const_type_info_type_node, exp); |
355 | |
356 | if (TYPE_POLYMORPHIC_P (TREE_TYPE (exp)) |
357 | && ! resolves_to_fixed_type_p (exp, &nonnull) |
358 | && ! nonnull) |
359 | { |
360 | /* So we need to look into the vtable of the type of exp. |
361 | Make sure it isn't a null lvalue. */ |
362 | exp = cp_build_addr_expr (exp, complain); |
363 | exp = save_expr (exp); |
364 | cond = cp_convert (boolean_type_node, exp, complain); |
365 | exp = cp_build_fold_indirect_ref (exp); |
366 | } |
367 | |
368 | exp = get_tinfo_ptr_dynamic (exp, complain); |
369 | |
370 | if (exp == error_mark_node) |
371 | return error_mark_node; |
372 | |
373 | if (cond) |
374 | { |
375 | tree bad = throw_bad_typeid (); |
376 | |
377 | exp = build3 (COND_EXPR, TREE_TYPE (exp), cond, exp, bad); |
378 | } |
379 | else |
380 | mark_type_use (initial_expr); |
381 | |
382 | return cp_build_fold_indirect_ref (exp); |
383 | } |
384 | |
385 | /* Generate the NTBS name of a type. If MARK_PRIVATE, put a '*' in front so that |
386 | comparisons will be done by pointer rather than string comparison. */ |
387 | static tree |
388 | tinfo_name (tree type, bool mark_private) |
389 | { |
390 | const char *name; |
391 | int length; |
392 | tree name_string; |
393 | |
394 | name = mangle_type_string (type); |
395 | length = strlen (s: name); |
396 | |
397 | if (mark_private) |
398 | { |
399 | /* Inject '*' at beginning of name to force pointer comparison. */ |
400 | char* buf = (char*) XALLOCAVEC (char, length + 2); |
401 | buf[0] = '*'; |
402 | memcpy (dest: buf + 1, src: name, n: length + 1); |
403 | name_string = build_string (length + 2, buf); |
404 | } |
405 | else |
406 | name_string = build_string (length + 1, name); |
407 | |
408 | return fix_string_type (name_string); |
409 | } |
410 | |
411 | /* Return a VAR_DECL for the internal ABI defined type_info object for |
412 | TYPE. You must arrange that the decl is mark_used, if actually use |
413 | it --- decls in vtables are only used if the vtable is output. */ |
414 | |
415 | tree |
416 | get_tinfo_decl (tree type) |
417 | { |
418 | if (variably_modified_type_p (type, /*fn=*/NULL_TREE)) |
419 | { |
420 | error ("cannot create type information for type %qT because " |
421 | "it involves types of variable size", |
422 | type); |
423 | return error_mark_node; |
424 | } |
425 | |
426 | if (TREE_CODE (type) == METHOD_TYPE) |
427 | type = build_function_type (TREE_TYPE (type), |
428 | TREE_CHAIN (TYPE_ARG_TYPES (type))); |
429 | |
430 | return get_tinfo_decl_direct (type, NULL, -1); |
431 | } |
432 | |
433 | /* Get or create a tinfo VAR_DECL directly from the provided information. |
434 | The caller must have already checked it is valid to do so. */ |
435 | |
436 | tree |
437 | get_tinfo_decl_direct (tree type, tree name, int pseudo_ix) |
438 | { |
439 | /* For a class type, the variable is cached in the type node |
440 | itself. */ |
441 | tree d = NULL_TREE; |
442 | |
443 | gcc_checking_assert (TREE_CODE (type) != METHOD_TYPE); |
444 | |
445 | if (CLASS_TYPE_P (type)) |
446 | d = CLASSTYPE_TYPEINFO_VAR (TYPE_MAIN_VARIANT (type)); |
447 | |
448 | if (!name) |
449 | name = mangle_typeinfo_for_type (type); |
450 | |
451 | if (!CLASS_TYPE_P (type) || TYPE_TRANSPARENT_AGGR (type)) |
452 | d = get_global_binding (id: name); |
453 | |
454 | if (!d) |
455 | { |
456 | /* Create it. */ |
457 | if (pseudo_ix < 0) |
458 | pseudo_ix = get_pseudo_ti_index (type); |
459 | |
460 | const tinfo_s *ti = get_tinfo_desc (pseudo_ix); |
461 | |
462 | d = build_lang_decl (VAR_DECL, name, ti->type); |
463 | SET_DECL_ASSEMBLER_NAME (d, name); |
464 | /* Remember the type it is for. */ |
465 | TREE_TYPE (name) = type; |
466 | DECL_TINFO_P (d) = 1; |
467 | DECL_ARTIFICIAL (d) = 1; |
468 | DECL_IGNORED_P (d) = 1; |
469 | TREE_READONLY (d) = 1; |
470 | TREE_STATIC (d) = 1; |
471 | TREE_ADDRESSABLE (d) = 1; |
472 | /* Tell equal_address_to that different tinfo decls never |
473 | overlap. */ |
474 | if (vec_safe_is_empty (v: unemitted_tinfo_decls)) |
475 | DECL_ATTRIBUTES (d) |
476 | = build_tree_list (get_identifier ("non overlapping"), |
477 | NULL_TREE); |
478 | else |
479 | DECL_ATTRIBUTES (d) |
480 | = DECL_ATTRIBUTES ((*unemitted_tinfo_decls)[0]); |
481 | |
482 | /* Mark the variable as undefined -- but remember that we can |
483 | define it later if we need to do so. */ |
484 | DECL_EXTERNAL (d) = 1; |
485 | DECL_NOT_REALLY_EXTERN (d) = 1; |
486 | set_linkage_according_to_type (type, d); |
487 | |
488 | d = pushdecl_top_level_and_finish (d, NULL_TREE); |
489 | if (CLASS_TYPE_P (type)) |
490 | CLASSTYPE_TYPEINFO_VAR (TYPE_MAIN_VARIANT (type)) = d; |
491 | |
492 | /* Add decl to the global array of tinfo decls. */ |
493 | vec_safe_push (v&: unemitted_tinfo_decls, obj: d); |
494 | } |
495 | |
496 | return d; |
497 | } |
498 | |
499 | /* Return the type_info object for TYPE. */ |
500 | |
501 | tree |
502 | get_typeid (tree type, tsubst_flags_t complain) |
503 | { |
504 | if (type == error_mark_node || !typeid_ok_p ()) |
505 | return error_mark_node; |
506 | |
507 | if (processing_template_decl) |
508 | return build_min (TYPEID_EXPR, const_type_info_type_node, type); |
509 | |
510 | /* If the type of the type-id is a reference type, the result of the |
511 | typeid expression refers to a type_info object representing the |
512 | referenced type. */ |
513 | type = non_reference (type); |
514 | |
515 | /* This is not one of the uses of a qualified function type in 8.3.5. */ |
516 | if (TREE_CODE (type) == FUNCTION_TYPE |
517 | && (type_memfn_quals (type) != TYPE_UNQUALIFIED |
518 | || type_memfn_rqual (type) != REF_QUAL_NONE)) |
519 | { |
520 | if (complain & tf_error) |
521 | error ("%<typeid%> of qualified function type %qT", type); |
522 | return error_mark_node; |
523 | } |
524 | |
525 | /* The top-level cv-qualifiers of the lvalue expression or the type-id |
526 | that is the operand of typeid are always ignored. */ |
527 | type = cv_unqualified (type); |
528 | |
529 | /* For UNKNOWN_TYPEs call complete_type_or_else to get diagnostics. */ |
530 | if (CLASS_TYPE_P (type) || type == unknown_type_node |
531 | || type == init_list_type_node) |
532 | type = complete_type_or_maybe_complain (type, NULL_TREE, complain); |
533 | |
534 | if (!type) |
535 | return error_mark_node; |
536 | |
537 | return cp_build_fold_indirect_ref (get_tinfo_ptr (type)); |
538 | } |
539 | |
540 | /* Check whether TEST is null before returning RESULT. If TEST is used in |
541 | RESULT, it must have previously had a save_expr applied to it. */ |
542 | |
543 | tree |
544 | build_if_nonnull (tree test, tree result, tsubst_flags_t complain) |
545 | { |
546 | tree null_ptr = cp_convert (TREE_TYPE (test), nullptr_node, complain); |
547 | tree cond = build2 (NE_EXPR, boolean_type_node, test, null_ptr); |
548 | |
549 | /* This is a compiler generated comparison, don't emit |
550 | e.g. -Wnonnull-compare warning for it. */ |
551 | suppress_warning (cond, OPT_Wnonnull); |
552 | |
553 | null_ptr = cp_convert (TREE_TYPE (result), nullptr_node, complain); |
554 | cond = build3 (COND_EXPR, TREE_TYPE (result), cond, result, null_ptr); |
555 | |
556 | /* Likewise, don't emit -Wnonnull for using the result to call |
557 | a member function. */ |
558 | suppress_warning (cond, OPT_Wnonnull); |
559 | return cond; |
560 | } |
561 | |
562 | /* Execute a dynamic cast, as described in section 5.2.6 of the 9/93 working |
563 | paper. */ |
564 | |
565 | static tree |
566 | build_dynamic_cast_1 (location_t loc, tree type, tree expr, |
567 | tsubst_flags_t complain) |
568 | { |
569 | enum tree_code tc = TREE_CODE (type); |
570 | tree exprtype; |
571 | tree dcast_fn; |
572 | tree old_expr = expr; |
573 | const char *errstr = NULL; |
574 | |
575 | /* Save casted types in the function's used types hash table. */ |
576 | used_types_insert (type); |
577 | |
578 | /* T shall be a pointer or reference to a complete class type, or |
579 | `pointer to cv void''. */ |
580 | switch (tc) |
581 | { |
582 | case POINTER_TYPE: |
583 | if (VOID_TYPE_P (TREE_TYPE (type))) |
584 | break; |
585 | /* Fall through. */ |
586 | case REFERENCE_TYPE: |
587 | if (! MAYBE_CLASS_TYPE_P (TREE_TYPE (type))) |
588 | { |
589 | errstr = _("target is not pointer or reference to class"); |
590 | goto fail; |
591 | } |
592 | if (!COMPLETE_TYPE_P (complete_type (TREE_TYPE (type)))) |
593 | { |
594 | errstr = _("target is not pointer or reference to complete type"); |
595 | goto fail; |
596 | } |
597 | break; |
598 | |
599 | default: |
600 | errstr = _("target is not pointer or reference"); |
601 | goto fail; |
602 | } |
603 | |
604 | if (tc == POINTER_TYPE) |
605 | { |
606 | expr = decay_conversion (expr, complain); |
607 | exprtype = TREE_TYPE (expr); |
608 | |
609 | /* If T is a pointer type, v shall be an rvalue of a pointer to |
610 | complete class type, and the result is an rvalue of type T. */ |
611 | |
612 | expr = mark_rvalue_use (expr); |
613 | |
614 | if (!TYPE_PTR_P (exprtype)) |
615 | { |
616 | errstr = _("source is not a pointer"); |
617 | goto fail; |
618 | } |
619 | if (! MAYBE_CLASS_TYPE_P (TREE_TYPE (exprtype))) |
620 | { |
621 | errstr = _("source is not a pointer to class"); |
622 | goto fail; |
623 | } |
624 | if (!COMPLETE_TYPE_P (complete_type (TREE_TYPE (exprtype)))) |
625 | { |
626 | errstr = _("source is a pointer to incomplete type"); |
627 | goto fail; |
628 | } |
629 | } |
630 | else |
631 | { |
632 | expr = mark_lvalue_use (expr); |
633 | exprtype = TREE_TYPE (expr); |
634 | |
635 | /* T is a reference type, v shall be an lvalue of a complete class |
636 | type, and the result is an lvalue of the type referred to by T. */ |
637 | if (! MAYBE_CLASS_TYPE_P (exprtype)) |
638 | { |
639 | errstr = _("source is not of class type"); |
640 | goto fail; |
641 | } |
642 | if (!COMPLETE_TYPE_P (complete_type (exprtype))) |
643 | { |
644 | errstr = _("source is of incomplete class type"); |
645 | goto fail; |
646 | } |
647 | |
648 | exprtype = cp_build_reference_type (exprtype, !lvalue_p (expr)); |
649 | } |
650 | |
651 | /* The dynamic_cast operator shall not cast away constness. */ |
652 | if (!at_least_as_qualified_p (TREE_TYPE (type), |
653 | TREE_TYPE (exprtype))) |
654 | { |
655 | errstr = _("conversion casts away constness"); |
656 | goto fail; |
657 | } |
658 | |
659 | /* If *type is an unambiguous accessible base class of *exprtype, |
660 | convert statically. */ |
661 | { |
662 | tree binfo = lookup_base (TREE_TYPE (exprtype), TREE_TYPE (type), |
663 | ba_check, NULL, complain); |
664 | if (binfo) |
665 | return build_static_cast (loc, type, expr, complain); |
666 | } |
667 | |
668 | /* Apply trivial conversion T -> T& for dereferenced ptrs. */ |
669 | if (tc == REFERENCE_TYPE) |
670 | expr = convert_to_reference (exprtype, expr, CONV_IMPLICIT, |
671 | LOOKUP_NORMAL, NULL_TREE, complain); |
672 | |
673 | /* Otherwise *exprtype must be a polymorphic class (have a vtbl). */ |
674 | if (TYPE_POLYMORPHIC_P (TREE_TYPE (exprtype))) |
675 | { |
676 | tree expr1; |
677 | /* if TYPE is `void *', return pointer to complete object. */ |
678 | if (tc == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (type))) |
679 | { |
680 | /* if b is an object, dynamic_cast<void *>(&b) == (void *)&b. */ |
681 | if (TREE_CODE (expr) == ADDR_EXPR |
682 | && VAR_P (TREE_OPERAND (expr, 0)) |
683 | && TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == RECORD_TYPE) |
684 | return build1 (NOP_EXPR, type, expr); |
685 | |
686 | /* Since expr is used twice below, save it. */ |
687 | expr = save_expr (expr); |
688 | |
689 | expr1 = build_headof (exp: expr); |
690 | if (TREE_TYPE (expr1) != type) |
691 | expr1 = build1 (NOP_EXPR, type, expr1); |
692 | return build_if_nonnull (test: expr, result: expr1, complain); |
693 | } |
694 | else |
695 | { |
696 | tree retval; |
697 | tree result, td2, td3; |
698 | tree elems[4]; |
699 | tree static_type, target_type, boff; |
700 | |
701 | /* If we got here, we can't convert statically. Therefore, |
702 | dynamic_cast<D&>(b) (b an object) cannot succeed. */ |
703 | if (tc == REFERENCE_TYPE) |
704 | { |
705 | if (VAR_P (old_expr) |
706 | && TREE_CODE (TREE_TYPE (old_expr)) == RECORD_TYPE) |
707 | { |
708 | tree expr = throw_bad_cast (); |
709 | if (complain & tf_warning) |
710 | warning_at (loc, 0, |
711 | "%<dynamic_cast<%#T>(%#D)%> can never succeed", |
712 | type, old_expr); |
713 | /* Bash it to the expected type. */ |
714 | TREE_TYPE (expr) = type; |
715 | return expr; |
716 | } |
717 | } |
718 | /* Ditto for dynamic_cast<D*>(&b). */ |
719 | else if (TREE_CODE (expr) == ADDR_EXPR) |
720 | { |
721 | tree op = TREE_OPERAND (expr, 0); |
722 | if (VAR_P (op) |
723 | && TREE_CODE (TREE_TYPE (op)) == RECORD_TYPE) |
724 | { |
725 | if (complain & tf_warning) |
726 | warning_at (loc, 0, |
727 | "%<dynamic_cast<%#T>(%#D)%> can never succeed", |
728 | type, op); |
729 | retval = build_int_cst (type, 0); |
730 | return retval; |
731 | } |
732 | } |
733 | |
734 | /* Use of dynamic_cast when -fno-rtti is prohibited. */ |
735 | if (!flag_rtti) |
736 | { |
737 | if (complain & tf_error) |
738 | error_at (loc, |
739 | "%<dynamic_cast%> not permitted with %<-fno-rtti%>"); |
740 | return error_mark_node; |
741 | } |
742 | |
743 | target_type = TYPE_MAIN_VARIANT (TREE_TYPE (type)); |
744 | static_type = TYPE_MAIN_VARIANT (TREE_TYPE (exprtype)); |
745 | td2 = get_tinfo_decl (type: target_type); |
746 | if (!mark_used (td2, complain) && !(complain & tf_error)) |
747 | return error_mark_node; |
748 | td2 = cp_build_addr_expr (td2, complain); |
749 | td3 = get_tinfo_decl (type: static_type); |
750 | if (!mark_used (td3, complain) && !(complain & tf_error)) |
751 | return error_mark_node; |
752 | td3 = cp_build_addr_expr (td3, complain); |
753 | |
754 | /* Determine how T and V are related. */ |
755 | boff = dcast_base_hint (static_type, target_type); |
756 | |
757 | /* Since expr is used twice below, save it. */ |
758 | expr = save_expr (expr); |
759 | |
760 | expr1 = expr; |
761 | if (tc == REFERENCE_TYPE) |
762 | expr1 = cp_build_addr_expr (expr1, complain); |
763 | |
764 | elems[0] = expr1; |
765 | elems[1] = td3; |
766 | elems[2] = td2; |
767 | elems[3] = boff; |
768 | |
769 | dcast_fn = dynamic_cast_node; |
770 | if (!dcast_fn) |
771 | { |
772 | unsigned flags = push_abi_namespace (); |
773 | tree tinfo_ptr = xref_tag (class_type, |
774 | get_identifier ("__class_type_info")); |
775 | tinfo_ptr = cp_build_qualified_type (tinfo_ptr, TYPE_QUAL_CONST); |
776 | tinfo_ptr = build_pointer_type (tinfo_ptr); |
777 | |
778 | const char *fn_name = "__dynamic_cast"; |
779 | /* void *() (void const *, __class_type_info const *, |
780 | __class_type_info const *, ptrdiff_t) */ |
781 | tree fn_type = (build_function_type_list |
782 | (ptr_type_node, const_ptr_type_node, |
783 | tinfo_ptr, tinfo_ptr, ptrdiff_type_node, |
784 | NULL_TREE)); |
785 | dcast_fn = (build_library_fn_ptr |
786 | (fn_name, fn_type, ECF_LEAF | ECF_PURE | ECF_NOTHROW)); |
787 | /* As with __cxa_atexit in get_atexit_node. */ |
788 | DECL_CONTEXT (dcast_fn) = FROB_CONTEXT (current_namespace); |
789 | DECL_SOURCE_LOCATION (dcast_fn) = BUILTINS_LOCATION; |
790 | dcast_fn = pushdecl (dcast_fn, /*hiding=*/true); |
791 | pop_abi_namespace (flags); |
792 | dynamic_cast_node = dcast_fn; |
793 | } |
794 | if (dcast_fn == error_mark_node) |
795 | return error_mark_node; |
796 | result = build_cxx_call (dcast_fn, 4, elems, complain); |
797 | SET_EXPR_LOCATION (result, loc); |
798 | |
799 | if (tc == REFERENCE_TYPE) |
800 | { |
801 | tree bad = throw_bad_cast (); |
802 | tree neq; |
803 | |
804 | result = save_expr (result); |
805 | neq = cp_truthvalue_conversion (result, complain); |
806 | return cp_convert (type, |
807 | build3 (COND_EXPR, TREE_TYPE (result), |
808 | neq, result, bad), complain); |
809 | } |
810 | |
811 | /* Now back to the type we want from a void*. */ |
812 | result = cp_convert (type, result, complain); |
813 | return build_if_nonnull (test: expr, result, complain); |
814 | } |
815 | } |
816 | else |
817 | errstr = _("source type is not polymorphic"); |
818 | |
819 | fail: |
820 | if (complain & tf_error) |
821 | error_at (loc, "cannot %<dynamic_cast%> %qE (of type %q#T) " |
822 | "to type %q#T (%s)", |
823 | old_expr, TREE_TYPE (old_expr), type, errstr); |
824 | return error_mark_node; |
825 | } |
826 | |
827 | tree |
828 | build_dynamic_cast (location_t loc, tree type, tree expr, |
829 | tsubst_flags_t complain) |
830 | { |
831 | tree r; |
832 | |
833 | if (type == error_mark_node || expr == error_mark_node) |
834 | return error_mark_node; |
835 | |
836 | if (processing_template_decl) |
837 | { |
838 | expr = build_min (DYNAMIC_CAST_EXPR, type, expr); |
839 | TREE_SIDE_EFFECTS (expr) = 1; |
840 | r = convert_from_reference (expr); |
841 | protected_set_expr_location (r, loc); |
842 | return r; |
843 | } |
844 | |
845 | r = convert_from_reference (build_dynamic_cast_1 (loc, type, expr, |
846 | complain)); |
847 | if (r != error_mark_node) |
848 | maybe_warn_about_useless_cast (loc, type, expr, complain); |
849 | protected_set_expr_location (r, loc); |
850 | return r; |
851 | } |
852 | |
853 | /* Return the runtime bit mask encoding the qualifiers of TYPE. */ |
854 | |
855 | static int |
856 | qualifier_flags (tree type) |
857 | { |
858 | int flags = 0; |
859 | int quals = cp_type_quals (type); |
860 | |
861 | if (quals & TYPE_QUAL_CONST) |
862 | flags |= 1; |
863 | if (quals & TYPE_QUAL_VOLATILE) |
864 | flags |= 2; |
865 | if (quals & TYPE_QUAL_RESTRICT) |
866 | flags |= 4; |
867 | return flags; |
868 | } |
869 | |
870 | /* Return true, if the pointer chain TYPE ends at an incomplete type, or |
871 | contains a pointer to member of an incomplete class. */ |
872 | |
873 | static bool |
874 | target_incomplete_p (tree type) |
875 | { |
876 | while (true) |
877 | if (TYPE_PTRDATAMEM_P (type)) |
878 | { |
879 | if (!COMPLETE_TYPE_P (TYPE_PTRMEM_CLASS_TYPE (type))) |
880 | return true; |
881 | type = TYPE_PTRMEM_POINTED_TO_TYPE (type); |
882 | } |
883 | else if (TYPE_PTR_P (type)) |
884 | type = TREE_TYPE (type); |
885 | else |
886 | return !COMPLETE_OR_VOID_TYPE_P (type); |
887 | } |
888 | |
889 | /* Returns true if TYPE involves an incomplete class type; in that |
890 | case, typeinfo variables for TYPE should be emitted with internal |
891 | linkage. */ |
892 | |
893 | static bool |
894 | involves_incomplete_p (tree type) |
895 | { |
896 | switch (TREE_CODE (type)) |
897 | { |
898 | case POINTER_TYPE: |
899 | return target_incomplete_p (TREE_TYPE (type)); |
900 | |
901 | case OFFSET_TYPE: |
902 | ptrmem: |
903 | return |
904 | (target_incomplete_p (TYPE_PTRMEM_POINTED_TO_TYPE (type)) |
905 | || !COMPLETE_TYPE_P (TYPE_PTRMEM_CLASS_TYPE (type))); |
906 | |
907 | case RECORD_TYPE: |
908 | if (TYPE_PTRMEMFUNC_P (type)) |
909 | goto ptrmem; |
910 | /* Fall through. */ |
911 | case UNION_TYPE: |
912 | if (!COMPLETE_TYPE_P (type)) |
913 | return true; |
914 | /* Fall through. */ |
915 | default: |
916 | /* All other types do not involve incomplete class types. */ |
917 | return false; |
918 | } |
919 | } |
920 | |
921 | /* Return a CONSTRUCTOR for the common part of the type_info objects. This |
922 | is the vtable pointer and NTBS name. The NTBS name is emitted as a |
923 | comdat const char array, so it becomes a unique key for the type. Generate |
924 | and emit that VAR_DECL here. (We can't always emit the type_info itself |
925 | as comdat, because of pointers to incomplete.) */ |
926 | |
927 | static tree |
928 | tinfo_base_init (tinfo_s *ti, tree target) |
929 | { |
930 | tree init; |
931 | tree name_decl; |
932 | tree vtable_ptr; |
933 | vec<constructor_elt, va_gc> *v; |
934 | |
935 | { |
936 | tree name_name, name_string; |
937 | |
938 | /* Generate the NTBS array variable. */ |
939 | tree name_type = build_cplus_array_type |
940 | (cp_build_qualified_type (char_type_node, TYPE_QUAL_CONST), |
941 | NULL_TREE); |
942 | |
943 | /* Determine the name of the variable -- and remember with which |
944 | type it is associated. */ |
945 | name_name = mangle_typeinfo_string_for_type (target); |
946 | TREE_TYPE (name_name) = target; |
947 | |
948 | name_decl = build_lang_decl (VAR_DECL, name_name, name_type); |
949 | SET_DECL_ASSEMBLER_NAME (name_decl, name_name); |
950 | DECL_ARTIFICIAL (name_decl) = 1; |
951 | DECL_IGNORED_P (name_decl) = 1; |
952 | TREE_READONLY (name_decl) = 1; |
953 | TREE_STATIC (name_decl) = 1; |
954 | DECL_EXTERNAL (name_decl) = 0; |
955 | DECL_TINFO_P (name_decl) = 1; |
956 | set_linkage_according_to_type (target, name_decl); |
957 | import_export_decl (name_decl); |
958 | name_string = tinfo_name (type: target, mark_private: !TREE_PUBLIC (name_decl)); |
959 | DECL_INITIAL (name_decl) = name_string; |
960 | mark_used (name_decl); |
961 | pushdecl_top_level_and_finish (name_decl, name_string); |
962 | } |
963 | |
964 | vtable_ptr = ti->vtable; |
965 | if (!vtable_ptr) |
966 | { |
967 | int flags = push_abi_namespace (); |
968 | tree real_type = xref_tag (class_type, ti->name); |
969 | tree real_decl = TYPE_NAME (real_type); |
970 | DECL_SOURCE_LOCATION (real_decl) = BUILTINS_LOCATION; |
971 | pop_abi_namespace (flags); |
972 | |
973 | if (!COMPLETE_TYPE_P (real_type)) |
974 | { |
975 | /* We never saw a definition of this type, so we need to |
976 | tell the compiler that this is an exported class, as |
977 | indeed all of the __*_type_info classes are. */ |
978 | SET_CLASSTYPE_INTERFACE_KNOWN (real_type); |
979 | CLASSTYPE_INTERFACE_ONLY (real_type) = 1; |
980 | } |
981 | |
982 | vtable_ptr = get_vtable_decl (real_type, /*complete=*/1); |
983 | vtable_ptr = cp_build_addr_expr (vtable_ptr, tf_warning_or_error); |
984 | |
985 | /* We need to point into the middle of the vtable. */ |
986 | vtable_ptr = fold_build_pointer_plus |
987 | (vtable_ptr, |
988 | size_binop (MULT_EXPR, |
989 | size_int (2 * TARGET_VTABLE_DATA_ENTRY_DISTANCE), |
990 | TYPE_SIZE_UNIT (vtable_entry_type))); |
991 | |
992 | ti->vtable = vtable_ptr; |
993 | } |
994 | |
995 | vec_alloc (v, nelems: 2); |
996 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, vtable_ptr); |
997 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, |
998 | decay_conversion (name_decl, tf_warning_or_error)); |
999 | |
1000 | init = build_constructor (init_list_type_node, v); |
1001 | TREE_CONSTANT (init) = 1; |
1002 | TREE_STATIC (init) = 1; |
1003 | |
1004 | return init; |
1005 | } |
1006 | |
1007 | /* Return the CONSTRUCTOR expr for a type_info of TYPE. TI provides the |
1008 | information about the particular type_info derivation, which adds no |
1009 | additional fields to the type_info base. */ |
1010 | |
1011 | static tree |
1012 | generic_initializer (tinfo_s *ti, tree target) |
1013 | { |
1014 | tree init = tinfo_base_init (ti, target); |
1015 | |
1016 | init = build_constructor_single (init_list_type_node, NULL_TREE, init); |
1017 | TREE_CONSTANT (init) = 1; |
1018 | TREE_STATIC (init) = 1; |
1019 | return init; |
1020 | } |
1021 | |
1022 | /* Return the CONSTRUCTOR expr for a type_info of pointer TYPE. |
1023 | TI provides information about the particular type_info derivation, |
1024 | which adds target type and qualifier flags members to the type_info base. */ |
1025 | |
1026 | static tree |
1027 | ptr_initializer (tinfo_s *ti, tree target) |
1028 | { |
1029 | tree init = tinfo_base_init (ti, target); |
1030 | tree to = TREE_TYPE (target); |
1031 | int flags = qualifier_flags (type: to); |
1032 | bool incomplete = target_incomplete_p (type: to); |
1033 | vec<constructor_elt, va_gc> *v; |
1034 | vec_alloc (v, nelems: 3); |
1035 | |
1036 | if (incomplete) |
1037 | flags |= 8; |
1038 | if (tx_safe_fn_type_p (to)) |
1039 | { |
1040 | flags |= 0x20; |
1041 | to = tx_unsafe_fn_variant (to); |
1042 | } |
1043 | if (flag_noexcept_type |
1044 | && FUNC_OR_METHOD_TYPE_P (to) |
1045 | && TYPE_NOTHROW_P (to)) |
1046 | { |
1047 | flags |= 0x40; |
1048 | to = build_exception_variant (to, NULL_TREE); |
1049 | } |
1050 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, init); |
1051 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, build_int_cst (NULL_TREE, flags)); |
1052 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, |
1053 | get_void_tinfo_ptr (TYPE_MAIN_VARIANT (to))); |
1054 | |
1055 | init = build_constructor (init_list_type_node, v); |
1056 | TREE_CONSTANT (init) = 1; |
1057 | TREE_STATIC (init) = 1; |
1058 | return init; |
1059 | } |
1060 | |
1061 | /* Return the CONSTRUCTOR expr for a type_info of pointer to member data TYPE. |
1062 | TI provides information about the particular type_info derivation, |
1063 | which adds class, target type and qualifier flags members to the type_info |
1064 | base. */ |
1065 | |
1066 | static tree |
1067 | ptm_initializer (tinfo_s *ti, tree target) |
1068 | { |
1069 | tree init = tinfo_base_init (ti, target); |
1070 | tree to = TYPE_PTRMEM_POINTED_TO_TYPE (target); |
1071 | tree klass = TYPE_PTRMEM_CLASS_TYPE (target); |
1072 | int flags = qualifier_flags (type: to); |
1073 | bool incomplete = target_incomplete_p (type: to); |
1074 | vec<constructor_elt, va_gc> *v; |
1075 | vec_alloc (v, nelems: 4); |
1076 | |
1077 | if (incomplete) |
1078 | flags |= 0x8; |
1079 | if (!COMPLETE_TYPE_P (klass)) |
1080 | flags |= 0x10; |
1081 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, init); |
1082 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, build_int_cst (NULL_TREE, flags)); |
1083 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, |
1084 | get_void_tinfo_ptr (TYPE_MAIN_VARIANT (to))); |
1085 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, get_void_tinfo_ptr (klass)); |
1086 | |
1087 | init = build_constructor (init_list_type_node, v); |
1088 | TREE_CONSTANT (init) = 1; |
1089 | TREE_STATIC (init) = 1; |
1090 | return init; |
1091 | } |
1092 | |
1093 | /* Return the CONSTRUCTOR expr for a type_info of class TYPE. |
1094 | TI provides information about the particular __class_type_info derivation, |
1095 | which adds hint flags and N extra initializers to the type_info base. */ |
1096 | |
1097 | static tree |
1098 | class_initializer (tinfo_s *ti, tree target, unsigned n, ...) |
1099 | { |
1100 | tree init = tinfo_base_init (ti, target); |
1101 | va_list extra_inits; |
1102 | unsigned i; |
1103 | vec<constructor_elt, va_gc> *v; |
1104 | vec_alloc (v, nelems: n+1); |
1105 | |
1106 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, init); |
1107 | va_start (extra_inits, n); |
1108 | for (i = 0; i < n; i++) |
1109 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, va_arg (extra_inits, tree)); |
1110 | va_end (extra_inits); |
1111 | |
1112 | init = build_constructor (init_list_type_node, v); |
1113 | TREE_CONSTANT (init) = 1; |
1114 | TREE_STATIC (init) = 1; |
1115 | return init; |
1116 | } |
1117 | |
1118 | /* Returns true if the typeinfo for type should be placed in |
1119 | the runtime library. */ |
1120 | |
1121 | static bool |
1122 | typeinfo_in_lib_p (tree type) |
1123 | { |
1124 | /* The typeinfo objects for `T*' and `const T*' are in the runtime |
1125 | library for simple types T. */ |
1126 | if (TYPE_PTR_P (type) |
1127 | && (cp_type_quals (TREE_TYPE (type)) == TYPE_QUAL_CONST |
1128 | || cp_type_quals (TREE_TYPE (type)) == TYPE_UNQUALIFIED)) |
1129 | type = TREE_TYPE (type); |
1130 | |
1131 | switch (TREE_CODE (type)) |
1132 | { |
1133 | case INTEGER_TYPE: |
1134 | case BOOLEAN_TYPE: |
1135 | case REAL_TYPE: |
1136 | case VOID_TYPE: |
1137 | case NULLPTR_TYPE: |
1138 | return true; |
1139 | |
1140 | case LANG_TYPE: |
1141 | /* fall through. */ |
1142 | |
1143 | default: |
1144 | return false; |
1145 | } |
1146 | } |
1147 | |
1148 | /* Generate the initializer for the type info describing TYPE. TK_INDEX is |
1149 | the index of the descriptor in the tinfo_desc vector. */ |
1150 | |
1151 | static tree |
1152 | get_pseudo_ti_init (tree type, unsigned tk_index) |
1153 | { |
1154 | tinfo_s *ti = get_tinfo_desc (tk_index); |
1155 | |
1156 | gcc_assert (at_eof); |
1157 | switch (tk_index) |
1158 | { |
1159 | case TK_POINTER_MEMBER_TYPE: |
1160 | return ptm_initializer (ti, target: type); |
1161 | |
1162 | case TK_POINTER_TYPE: |
1163 | return ptr_initializer (ti, target: type); |
1164 | |
1165 | case TK_BUILTIN_TYPE: |
1166 | case TK_ENUMERAL_TYPE: |
1167 | case TK_FUNCTION_TYPE: |
1168 | case TK_ARRAY_TYPE: |
1169 | return generic_initializer (ti, target: type); |
1170 | |
1171 | case TK_CLASS_TYPE: |
1172 | return class_initializer (ti, target: type, n: 0); |
1173 | |
1174 | case TK_SI_CLASS_TYPE: |
1175 | { |
1176 | tree base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), 0); |
1177 | tree tinfo = get_void_tinfo_ptr (BINFO_TYPE (base_binfo)); |
1178 | |
1179 | /* get_tinfo_ptr might have reallocated the tinfo_descs vector. */ |
1180 | ti = &(*tinfo_descs)[tk_index]; |
1181 | return class_initializer (ti, target: type, n: 1, tinfo); |
1182 | } |
1183 | |
1184 | default: |
1185 | { |
1186 | int hint = ((CLASSTYPE_REPEATED_BASE_P (type) << 0) |
1187 | | (CLASSTYPE_DIAMOND_SHAPED_P (type) << 1)); |
1188 | tree binfo = TYPE_BINFO (type); |
1189 | unsigned nbases = BINFO_N_BASE_BINFOS (binfo); |
1190 | vec<tree, va_gc> *base_accesses = BINFO_BASE_ACCESSES (binfo); |
1191 | tree offset_type = LONGPTR_T; |
1192 | vec<constructor_elt, va_gc> *init_vec = NULL; |
1193 | |
1194 | gcc_assert (tk_index - TK_VMI_CLASS_TYPES + 1 == nbases); |
1195 | |
1196 | vec_safe_grow (v&: init_vec, len: nbases, exact: true); |
1197 | /* Generate the base information initializer. */ |
1198 | for (unsigned ix = nbases; ix--;) |
1199 | { |
1200 | tree base_binfo = BINFO_BASE_BINFO (binfo, ix); |
1201 | int flags = 0; |
1202 | tree tinfo; |
1203 | tree offset; |
1204 | vec<constructor_elt, va_gc> *v; |
1205 | |
1206 | if ((*base_accesses)[ix] == access_public_node) |
1207 | flags |= 2; |
1208 | tinfo = get_void_tinfo_ptr (BINFO_TYPE (base_binfo)); |
1209 | if (BINFO_VIRTUAL_P (base_binfo)) |
1210 | { |
1211 | /* We store the vtable offset at which the virtual |
1212 | base offset can be found. */ |
1213 | offset = BINFO_VPTR_FIELD (base_binfo); |
1214 | flags |= 1; |
1215 | } |
1216 | else |
1217 | offset = BINFO_OFFSET (base_binfo); |
1218 | |
1219 | /* Combine offset and flags into one field. */ |
1220 | offset = fold_convert (offset_type, offset); |
1221 | offset = fold_build2_loc (input_location, |
1222 | LSHIFT_EXPR, offset_type, offset, |
1223 | build_int_cst (offset_type, 8)); |
1224 | offset = fold_build2_loc (input_location, |
1225 | BIT_IOR_EXPR, offset_type, offset, |
1226 | build_int_cst (offset_type, flags)); |
1227 | vec_alloc (v, nelems: 2); |
1228 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, tinfo); |
1229 | CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, offset); |
1230 | tree base_init = build_constructor (init_list_type_node, v); |
1231 | constructor_elt *e = &(*init_vec)[ix]; |
1232 | e->index = NULL_TREE; |
1233 | e->value = base_init; |
1234 | } |
1235 | tree base_inits = build_constructor (init_list_type_node, init_vec); |
1236 | |
1237 | /* get_tinfo_ptr might have reallocated the tinfo_descs vector. */ |
1238 | ti = &(*tinfo_descs)[tk_index]; |
1239 | return class_initializer (ti, target: type, n: 3, |
1240 | build_int_cst (NULL_TREE, hint), |
1241 | build_int_cst (NULL_TREE, nbases), |
1242 | base_inits); |
1243 | } |
1244 | } |
1245 | } |
1246 | |
1247 | /* Return the index of a pseudo type info type node used to describe |
1248 | TYPE. TYPE must be a complete type (or cv void), except at the end |
1249 | of the translation unit. */ |
1250 | |
1251 | static unsigned |
1252 | get_pseudo_ti_index (tree type) |
1253 | { |
1254 | unsigned ix; |
1255 | |
1256 | switch (TREE_CODE (type)) |
1257 | { |
1258 | case OFFSET_TYPE: |
1259 | ix = TK_POINTER_MEMBER_TYPE; |
1260 | break; |
1261 | |
1262 | case POINTER_TYPE: |
1263 | ix = TK_POINTER_TYPE; |
1264 | break; |
1265 | |
1266 | case ENUMERAL_TYPE: |
1267 | ix = TK_ENUMERAL_TYPE; |
1268 | break; |
1269 | |
1270 | case FUNCTION_TYPE: |
1271 | ix = TK_FUNCTION_TYPE; |
1272 | break; |
1273 | |
1274 | case ARRAY_TYPE: |
1275 | ix = TK_ARRAY_TYPE; |
1276 | break; |
1277 | |
1278 | case UNION_TYPE: |
1279 | case RECORD_TYPE: |
1280 | if (TYPE_PTRMEMFUNC_P (type)) |
1281 | ix = TK_POINTER_MEMBER_TYPE; |
1282 | else if (!COMPLETE_TYPE_P (type)) |
1283 | { |
1284 | if (!at_eof) |
1285 | cxx_incomplete_type_error (NULL_TREE, type); |
1286 | ix = TK_CLASS_TYPE; |
1287 | } |
1288 | else if (!TYPE_BINFO (type) |
1289 | || !BINFO_N_BASE_BINFOS (TYPE_BINFO (type))) |
1290 | ix = TK_CLASS_TYPE; |
1291 | else |
1292 | { |
1293 | tree binfo = TYPE_BINFO (type); |
1294 | vec<tree, va_gc> *base_accesses = BINFO_BASE_ACCESSES (binfo); |
1295 | tree base_binfo = BINFO_BASE_BINFO (binfo, 0); |
1296 | int num_bases = BINFO_N_BASE_BINFOS (binfo); |
1297 | |
1298 | if (num_bases == 1 |
1299 | && (*base_accesses)[0] == access_public_node |
1300 | && !BINFO_VIRTUAL_P (base_binfo) |
1301 | && integer_zerop (BINFO_OFFSET (base_binfo))) |
1302 | /* single non-virtual public. */ |
1303 | ix = TK_SI_CLASS_TYPE; |
1304 | else |
1305 | ix = TK_VMI_CLASS_TYPES + num_bases - 1; |
1306 | } |
1307 | break; |
1308 | |
1309 | default: |
1310 | ix = TK_BUILTIN_TYPE; |
1311 | break; |
1312 | } |
1313 | return ix; |
1314 | } |
1315 | |
1316 | /* Return pointer to tinfo descriptor. Possibly creating the tinfo |
1317 | descriptor in the first place. */ |
1318 | |
1319 | static tinfo_s * |
1320 | get_tinfo_desc (unsigned ix) |
1321 | { |
1322 | if (tinfo_descs->length () <= ix) |
1323 | /* too short, extend. */ |
1324 | vec_safe_grow_cleared (v&: tinfo_descs, len: ix + 1); |
1325 | |
1326 | tinfo_s *res = &(*tinfo_descs)[ix]; |
1327 | |
1328 | if (res->type) |
1329 | return res; |
1330 | |
1331 | /* Ok, we have to create it. This layout must be consistent with |
1332 | that defined in the runtime support. We explicitly manage the |
1333 | vtable member, and name it for real type as used in the runtime. |
1334 | The RECORD type has a different name, to avoid collisions. We |
1335 | have to delay generating the VAR_DECL of the vtable until the end |
1336 | of the translation, when we'll have seen the library definition, |
1337 | if there was one. */ |
1338 | |
1339 | /* Fields to add, chained in reverse order. */ |
1340 | tree fields = NULL_TREE; |
1341 | |
1342 | if (ix >= TK_DERIVED_TYPES) |
1343 | { |
1344 | /* First field is the pseudo type_info base class. */ |
1345 | tree fld_base = build_decl (BUILTINS_LOCATION, FIELD_DECL, NULL_TREE, |
1346 | get_tinfo_desc (ix: TK_TYPE_INFO_TYPE)->type); |
1347 | |
1348 | DECL_CHAIN (fld_base) = fields; |
1349 | fields = fld_base; |
1350 | } |
1351 | |
1352 | switch (ix) |
1353 | { |
1354 | case TK_TYPE_INFO_TYPE: |
1355 | { |
1356 | tree fld_ptr = build_decl (BUILTINS_LOCATION, FIELD_DECL, |
1357 | NULL_TREE, const_ptr_type_node); |
1358 | fields = fld_ptr; |
1359 | |
1360 | tree fld_str = build_decl (BUILTINS_LOCATION, FIELD_DECL, |
1361 | NULL_TREE, const_string_type_node); |
1362 | DECL_CHAIN (fld_str) = fields; |
1363 | fields = fld_str; |
1364 | break; |
1365 | } |
1366 | |
1367 | case TK_BASE_TYPE: |
1368 | { |
1369 | /* Base class internal helper. Pointer to base type, offset to |
1370 | base, flags. */ |
1371 | tree fld_ptr = build_decl (BUILTINS_LOCATION, FIELD_DECL, |
1372 | NULL_TREE, const_ptr_type_node); |
1373 | DECL_CHAIN (fld_ptr) = fields; |
1374 | fields = fld_ptr; |
1375 | |
1376 | tree fld_flag = build_decl (BUILTINS_LOCATION, FIELD_DECL, |
1377 | NULL_TREE, LONGPTR_T); |
1378 | DECL_CHAIN (fld_flag) = fields; |
1379 | fields = fld_flag; |
1380 | break; |
1381 | } |
1382 | |
1383 | case TK_BUILTIN_TYPE: |
1384 | /* Fundamental type_info */ |
1385 | break; |
1386 | |
1387 | case TK_ARRAY_TYPE: |
1388 | break; |
1389 | |
1390 | case TK_FUNCTION_TYPE: |
1391 | break; |
1392 | |
1393 | case TK_ENUMERAL_TYPE: |
1394 | break; |
1395 | |
1396 | case TK_POINTER_TYPE: |
1397 | case TK_POINTER_MEMBER_TYPE: |
1398 | { |
1399 | /* Pointer type_info. Adds two fields, qualification mask and |
1400 | pointer to the pointed to type. This is really a |
1401 | descendant of __pbase_type_info. */ |
1402 | tree fld_mask = build_decl (BUILTINS_LOCATION, FIELD_DECL, |
1403 | NULL_TREE, integer_type_node); |
1404 | DECL_CHAIN (fld_mask) = fields; |
1405 | fields = fld_mask; |
1406 | |
1407 | tree fld_ptr = build_decl (BUILTINS_LOCATION, FIELD_DECL, |
1408 | NULL_TREE, const_ptr_type_node); |
1409 | DECL_CHAIN (fld_ptr) = fields; |
1410 | fields = fld_ptr; |
1411 | |
1412 | if (ix == TK_POINTER_MEMBER_TYPE) |
1413 | { |
1414 | /* Add a pointer to the class too. */ |
1415 | tree fld_cls = build_decl (BUILTINS_LOCATION, FIELD_DECL, |
1416 | NULL_TREE, const_ptr_type_node); |
1417 | DECL_CHAIN (fld_cls) = fields; |
1418 | fields = fld_cls; |
1419 | } |
1420 | break; |
1421 | } |
1422 | |
1423 | case TK_CLASS_TYPE: |
1424 | /* Class type_info. No additional fields. */ |
1425 | break; |
1426 | |
1427 | case TK_SI_CLASS_TYPE: |
1428 | { |
1429 | /* Single public non-virtual base class. Add pointer to base |
1430 | class. This is really a descendant of |
1431 | __class_type_info. */ |
1432 | tree fld_ptr = build_decl (BUILTINS_LOCATION, FIELD_DECL, |
1433 | NULL_TREE, const_ptr_type_node); |
1434 | DECL_CHAIN (fld_ptr) = fields; |
1435 | fields = fld_ptr; |
1436 | break; |
1437 | } |
1438 | |
1439 | default: /* Multiple inheritance. */ |
1440 | { |
1441 | unsigned num_bases = ix - TK_VMI_CLASS_TYPES + 1; |
1442 | |
1443 | tree fld_flg = build_decl (BUILTINS_LOCATION, FIELD_DECL, |
1444 | NULL_TREE, integer_type_node); |
1445 | DECL_CHAIN (fld_flg) = fields; |
1446 | fields = fld_flg; |
1447 | |
1448 | tree fld_cnt = build_decl (BUILTINS_LOCATION, FIELD_DECL, |
1449 | NULL_TREE, integer_type_node); |
1450 | DECL_CHAIN (fld_cnt) = fields; |
1451 | fields = fld_cnt; |
1452 | |
1453 | /* Create the array of __base_class_type_info entries. */ |
1454 | tree domain = build_index_type (size_int (num_bases - 1)); |
1455 | tree array = build_array_type (get_tinfo_desc (ix: TK_BASE_TYPE)->type, |
1456 | domain); |
1457 | tree fld_ary = build_decl (BUILTINS_LOCATION, FIELD_DECL, |
1458 | NULL_TREE, array); |
1459 | DECL_CHAIN (fld_ary) = fields; |
1460 | fields = fld_ary; |
1461 | break; |
1462 | } |
1463 | } |
1464 | |
1465 | /* Generate the pseudo type name. */ |
1466 | const char *real_name = tinfo_names[ix < TK_VMI_CLASS_TYPES |
1467 | ? ix : unsigned (TK_VMI_CLASS_TYPES)]; |
1468 | size_t name_len = strlen (s: real_name); |
1469 | char *pseudo_name = (char *) alloca (name_len + 30); |
1470 | memcpy (dest: pseudo_name, src: real_name, n: name_len); |
1471 | /* Those >= TK_VMI_CLASS_TYPES need a discriminator, may as well |
1472 | apply it to all. See get_peudo_tinfo_index where we make use of |
1473 | this. */ |
1474 | sprintf (s: pseudo_name + name_len, format: "_pseudo_%d", ix); |
1475 | |
1476 | /* Create the pseudo type. */ |
1477 | tree pseudo_type = make_class_type (RECORD_TYPE); |
1478 | /* Pass the fields chained in reverse. */ |
1479 | finish_builtin_struct (pseudo_type, pseudo_name, fields, NULL_TREE); |
1480 | CLASSTYPE_AS_BASE (pseudo_type) = pseudo_type; |
1481 | DECL_CONTEXT (TYPE_NAME (pseudo_type)) = FROB_CONTEXT (global_namespace); |
1482 | DECL_TINFO_P (TYPE_NAME (pseudo_type)) = true; |
1483 | xref_basetypes (pseudo_type, /*bases=*/NULL_TREE); |
1484 | |
1485 | res->type = cp_build_qualified_type (pseudo_type, TYPE_QUAL_CONST); |
1486 | res->name = get_identifier (real_name); |
1487 | |
1488 | /* Pretend this is public so determine_visibility doesn't give vtables |
1489 | internal linkage. */ |
1490 | TREE_PUBLIC (TYPE_MAIN_DECL (res->type)) = 1; |
1491 | |
1492 | return res; |
1493 | } |
1494 | |
1495 | /* Return an identifying index for the pseudo type_info TYPE. |
1496 | We wrote the index at the end of the name, so just scan it from |
1497 | there. This isn't critical, as it's only on the first use of this |
1498 | type during module stream out. */ |
1499 | |
1500 | unsigned |
1501 | get_pseudo_tinfo_index (tree type) |
1502 | { |
1503 | tree name = DECL_NAME (TYPE_NAME (type)); |
1504 | unsigned ix = 0, scale = 1; |
1505 | size_t len = IDENTIFIER_LENGTH (name); |
1506 | const char *ptr = IDENTIFIER_POINTER (name) + len; |
1507 | |
1508 | for (; *--ptr != '_'; scale *= 10) |
1509 | { |
1510 | len--; |
1511 | gcc_checking_assert (len && ISDIGIT (*ptr)); |
1512 | ix += (*ptr - '0') * scale; |
1513 | } |
1514 | |
1515 | gcc_assert (len != IDENTIFIER_LENGTH (name)); |
1516 | return ix; |
1517 | } |
1518 | |
1519 | tree |
1520 | get_pseudo_tinfo_type (unsigned ix) |
1521 | { |
1522 | return get_tinfo_desc (ix)->type; |
1523 | } |
1524 | |
1525 | /* We lazily create the type info types. */ |
1526 | |
1527 | static void |
1528 | create_tinfo_types (void) |
1529 | { |
1530 | gcc_assert (!tinfo_descs); |
1531 | |
1532 | vec_alloc (v&: tinfo_descs, nelems: TK_MAX + 20); |
1533 | } |
1534 | |
1535 | /* Helper for emit_support_tinfos. Emits the type_info descriptor of |
1536 | a single type. */ |
1537 | |
1538 | void |
1539 | emit_support_tinfo_1 (tree bltn) |
1540 | { |
1541 | tree types[3]; |
1542 | |
1543 | if (bltn == NULL_TREE) |
1544 | return; |
1545 | types[0] = bltn; |
1546 | types[1] = build_pointer_type (bltn); |
1547 | types[2] = build_pointer_type (cp_build_qualified_type (bltn, |
1548 | TYPE_QUAL_CONST)); |
1549 | |
1550 | for (int i = 0; i < 3; ++i) |
1551 | { |
1552 | tree tinfo = get_tinfo_decl (type: types[i]); |
1553 | TREE_USED (tinfo) = 1; |
1554 | mark_needed (tinfo); |
1555 | /* The C++ ABI requires that these objects be COMDAT. But, |
1556 | On systems without weak symbols, initialized COMDAT |
1557 | objects are emitted with internal linkage. (See |
1558 | comdat_linkage for details.) Since we want these objects |
1559 | to have external linkage so that copies do not have to be |
1560 | emitted in code outside the runtime library, we make them |
1561 | non-COMDAT here. |
1562 | |
1563 | It might also not be necessary to follow this detail of the |
1564 | ABI. */ |
1565 | if (!flag_weak || ! targetm.cxx.library_rtti_comdat ()) |
1566 | { |
1567 | gcc_assert (TREE_PUBLIC (tinfo) && !DECL_COMDAT (tinfo)); |
1568 | DECL_INTERFACE_KNOWN (tinfo) = 1; |
1569 | } |
1570 | |
1571 | /* Emit it right away if not emitted already. */ |
1572 | if (DECL_INITIAL (tinfo) == NULL_TREE) |
1573 | { |
1574 | bool ok = emit_tinfo_decl (tinfo); |
1575 | gcc_assert (ok); |
1576 | /* When compiling libsupc++.a (fundamental_type_info.o), |
1577 | unemitted_tinfo_decls->last () will be tinfo, so pop it |
1578 | from the vector as it is emitted now. If one uses typeid |
1579 | etc. in the same TU as the definition of |
1580 | ~fundamental_type_info (), the tinfo might be emitted |
1581 | already earlier, in such case keep it in the vector |
1582 | (as otherwise we'd need to walk the whole vector) and |
1583 | let c_parse_final_cleanups ignore it when it will have |
1584 | non-NULL DECL_INITIAL. */ |
1585 | if (unemitted_tinfo_decls->last () == tinfo) |
1586 | unemitted_tinfo_decls->pop (); |
1587 | } |
1588 | } |
1589 | } |
1590 | |
1591 | /* Emit the type_info descriptors which are guaranteed to be in the runtime |
1592 | support. Generating them here guarantees consistency with the other |
1593 | structures. We use the following heuristic to determine when the runtime |
1594 | is being generated. If std::__fundamental_type_info is defined, and its |
1595 | destructor is defined, then the runtime is being built. */ |
1596 | |
1597 | void |
1598 | emit_support_tinfos (void) |
1599 | { |
1600 | /* Dummy static variable so we can put nullptr in the array; it will be |
1601 | set before we actually start to walk the array. */ |
1602 | static tree *const fundamentals[] = |
1603 | { |
1604 | &void_type_node, |
1605 | &boolean_type_node, |
1606 | &wchar_type_node, &char8_type_node, &char16_type_node, &char32_type_node, |
1607 | &char_type_node, &signed_char_type_node, &unsigned_char_type_node, |
1608 | &short_integer_type_node, &short_unsigned_type_node, |
1609 | &integer_type_node, &unsigned_type_node, |
1610 | &long_integer_type_node, &long_unsigned_type_node, |
1611 | &long_long_integer_type_node, &long_long_unsigned_type_node, |
1612 | &float_type_node, &double_type_node, &long_double_type_node, |
1613 | &bfloat16_type_node, &float16_type_node, &float32_type_node, |
1614 | &float64_type_node, &float128_type_node, &float32x_type_node, |
1615 | &float64x_type_node, &float128x_type_node, &nullptr_type_node, |
1616 | 0 |
1617 | }; |
1618 | /* Similar, but for floating point types only which should get type info |
1619 | regardless whether they are non-NULL or NULL. */ |
1620 | static tree *const fundamentals_with_fallback[] = |
1621 | { |
1622 | &dfloat32_type_node, &dfloat64_type_node, &dfloat128_type_node, |
1623 | 0 |
1624 | }; |
1625 | int ix; |
1626 | |
1627 | /* Look for a defined class. */ |
1628 | tree bltn_type = lookup_qualified_name |
1629 | (abi_node, name: "__fundamental_type_info", LOOK_want::TYPE, false); |
1630 | if (TREE_CODE (bltn_type) != TYPE_DECL) |
1631 | return; |
1632 | |
1633 | bltn_type = TREE_TYPE (bltn_type); |
1634 | if (!COMPLETE_TYPE_P (bltn_type)) |
1635 | return; |
1636 | tree dtor = CLASSTYPE_DESTRUCTOR (bltn_type); |
1637 | if (!dtor || DECL_EXTERNAL (dtor)) |
1638 | return; |
1639 | |
1640 | /* All these are really builtins. So set the location. */ |
1641 | location_t saved_loc = input_location; |
1642 | input_location = BUILTINS_LOCATION; |
1643 | doing_runtime = 1; |
1644 | tree fallback = NULL_TREE; |
1645 | for (ix = 0; fundamentals[ix]; ix++) |
1646 | emit_support_tinfo_1 (bltn: *fundamentals[ix]); |
1647 | for (ix = 0; fundamentals_with_fallback[ix]; ix++) |
1648 | if (*fundamentals_with_fallback[ix]) |
1649 | emit_support_tinfo_1 (bltn: *fundamentals_with_fallback[ix]); |
1650 | else |
1651 | { |
1652 | if (fallback == NULL_TREE) |
1653 | fallback = make_node (REAL_TYPE); |
1654 | *fundamentals_with_fallback[ix] = fallback; |
1655 | emit_support_tinfo_1 (bltn: fallback); |
1656 | *fundamentals_with_fallback[ix] = NULL_TREE; |
1657 | } |
1658 | for (ix = 0; ix < NUM_INT_N_ENTS; ix ++) |
1659 | if (int_n_enabled_p[ix]) |
1660 | { |
1661 | emit_support_tinfo_1 (bltn: int_n_trees[ix].signed_type); |
1662 | emit_support_tinfo_1 (bltn: int_n_trees[ix].unsigned_type); |
1663 | } |
1664 | for (tree t = registered_builtin_types; t; t = TREE_CHAIN (t)) |
1665 | emit_support_tinfo_1 (TREE_VALUE (t)); |
1666 | |
1667 | /* Emit additional typeinfos as requested by target. */ |
1668 | targetm.emit_support_tinfos (emit_support_tinfo_1); |
1669 | |
1670 | input_location = saved_loc; |
1671 | } |
1672 | |
1673 | /* Finish a type info decl. DECL_PTR is a pointer to an unemitted |
1674 | tinfo decl. Determine whether it needs emitting, and if so |
1675 | generate the initializer. */ |
1676 | |
1677 | bool |
1678 | emit_tinfo_decl (tree decl) |
1679 | { |
1680 | gcc_assert (DECL_TINFO_P (decl)); |
1681 | |
1682 | tree type = TREE_TYPE (DECL_NAME (decl)); |
1683 | if (typeinfo_in_lib_p (type)) |
1684 | { |
1685 | if (doing_runtime) |
1686 | DECL_EXTERNAL (decl) = 0; |
1687 | else |
1688 | { |
1689 | /* If we're not in the runtime, then DECL (which is already |
1690 | DECL_EXTERNAL) will not be defined here. */ |
1691 | DECL_INTERFACE_KNOWN (decl) = 1; |
1692 | return false; |
1693 | } |
1694 | } |
1695 | else if (involves_incomplete_p (type)) |
1696 | { |
1697 | if (!decl_needed_p (decl)) |
1698 | return false; |
1699 | /* If TYPE involves an incomplete class type, then the typeinfo |
1700 | object will be emitted with internal linkage. There is no |
1701 | way to know whether or not types are incomplete until the end |
1702 | of the compilation, so this determination must be deferred |
1703 | until this point. */ |
1704 | TREE_PUBLIC (decl) = 0; |
1705 | DECL_EXTERNAL (decl) = 0; |
1706 | DECL_INTERFACE_KNOWN (decl) = 1; |
1707 | } |
1708 | |
1709 | import_export_decl (decl); |
1710 | if (DECL_NOT_REALLY_EXTERN (decl) && decl_needed_p (decl)) |
1711 | { |
1712 | tree init; |
1713 | |
1714 | DECL_EXTERNAL (decl) = 0; |
1715 | int pseudo_ix = get_pseudo_ti_index (type); |
1716 | const tinfo_s *ti = get_tinfo_desc (ix: pseudo_ix); |
1717 | if (TREE_TYPE (decl) != ti->type) |
1718 | { |
1719 | /* If the class became complete since we first called get_tinfo_decl, |
1720 | its type_info descriptor may have switched from __class_type_info |
1721 | to e.g. __si_class_type_info. */ |
1722 | TREE_TYPE (decl) = ti->type; |
1723 | relayout_decl (decl); |
1724 | } |
1725 | init = get_pseudo_ti_init (type, tk_index: pseudo_ix); |
1726 | DECL_INITIAL (decl) = init; |
1727 | mark_used (decl); |
1728 | cp_finish_decl (decl, init, false, NULL_TREE, 0); |
1729 | /* Avoid targets optionally bumping up the alignment to improve |
1730 | vector instruction accesses, tinfo are never accessed this way. */ |
1731 | #ifdef DATA_ABI_ALIGNMENT |
1732 | SET_DECL_ALIGN (decl, DATA_ABI_ALIGNMENT (TREE_TYPE (decl), |
1733 | TYPE_ALIGN (TREE_TYPE (decl)))); |
1734 | DECL_USER_ALIGN (decl) = true; |
1735 | #endif |
1736 | return true; |
1737 | } |
1738 | else |
1739 | return false; |
1740 | } |
1741 | |
1742 | #include "gt-cp-rtti.h" |
1743 |
Definitions
- tinfo_s
- tinfo_kind
- tinfo_names
- unemitted_tinfo_decls
- tinfo_descs
- doing_runtime
- init_rtti_processing
- build_headof
- throw_bad_cast
- throw_bad_typeid
- type_info_ptr_type
- get_tinfo_ptr
- get_void_tinfo_ptr
- get_tinfo_ptr_dynamic
- typeid_ok_p
- build_typeid
- tinfo_name
- get_tinfo_decl
- get_tinfo_decl_direct
- get_typeid
- build_if_nonnull
- build_dynamic_cast_1
- build_dynamic_cast
- qualifier_flags
- target_incomplete_p
- involves_incomplete_p
- tinfo_base_init
- generic_initializer
- ptr_initializer
- ptm_initializer
- class_initializer
- typeinfo_in_lib_p
- get_pseudo_ti_init
- get_pseudo_ti_index
- get_tinfo_desc
- get_pseudo_tinfo_index
- get_pseudo_tinfo_type
- create_tinfo_types
- emit_support_tinfo_1
- emit_support_tinfos
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