1 /* RunTime Type Identification
2 Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001
3 Free Software Foundation, Inc.
4 Mostly written by Jason Merrill (jason@cygnus.com).
6 This file is part of GNU CC.
8 GNU CC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GNU CC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GNU CC; see the file COPYING. If not, write to
20 the Free Software Foundation, 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
33 /* Accessors for the type_info objects. We need to remember several things
34 about each of the type_info types. The global tree nodes such as
35 bltn_desc_type_node are TREE_LISTs, and these macros are used to access
36 the required information. */
37 /* The RECORD_TYPE of a type_info derived class. */
38 #define TINFO_PSEUDO_TYPE(NODE) TREE_TYPE (NODE)
39 /* The VAR_DECL of the vtable for the type_info derived class. */
40 #define TINFO_VTABLE_DECL(NODE) TREE_VALUE (NODE)
42 extern struct obstack permanent_obstack;
44 static tree build_headof_sub PARAMS((tree));
45 static tree build_headof PARAMS((tree));
46 static tree get_tinfo_var PARAMS((tree));
47 static tree ifnonnull PARAMS((tree, tree));
48 static tree tinfo_name PARAMS((tree));
49 static tree get_base_offset PARAMS((tree, tree));
50 static tree build_dynamic_cast_1 PARAMS((tree, tree));
51 static void expand_si_desc PARAMS((tree, tree));
52 static void expand_class_desc PARAMS((tree, tree));
53 static void expand_attr_desc PARAMS((tree, tree));
54 static void expand_ptr_desc PARAMS((tree, tree));
55 static void expand_generic_desc PARAMS((tree, tree, const char *));
56 static tree throw_bad_cast PARAMS((void));
57 static tree throw_bad_typeid PARAMS((void));
58 static tree get_tinfo_decl_dynamic PARAMS((tree));
59 static tree tinfo_from_decl PARAMS((tree));
60 static int qualifier_flags PARAMS((tree));
61 static int target_incomplete_p PARAMS((tree));
62 static tree tinfo_base_init PARAMS((tree, tree));
63 static tree generic_initializer PARAMS((tree, tree));
64 static tree ptr_initializer PARAMS((tree, tree, int *));
65 static tree ptm_initializer PARAMS((tree, tree, int *));
66 static tree dfs_class_hint_mark PARAMS ((tree, void *));
67 static tree dfs_class_hint_unmark PARAMS ((tree, void *));
68 static int class_hint_flags PARAMS((tree));
69 static tree class_initializer PARAMS((tree, tree, tree));
70 static tree synthesize_tinfo_var PARAMS((tree, tree));
71 static tree create_real_tinfo_var PARAMS((tree, tree, tree, int));
72 static tree create_pseudo_type_info PARAMS((const char *, int, ...));
73 static tree get_vmi_pseudo_type_info PARAMS((int));
74 static void create_tinfo_types PARAMS((void));
76 static int doing_runtime = 0;
79 init_rtti_processing ()
82 push_namespace (std_identifier);
83 type_info_type_node = xref_tag
84 (class_type_node, get_identifier ("type_info"), 1);
87 if (!new_abi_rtti_p ())
89 tinfo_decl_id = get_identifier ("__tf");
90 tinfo_decl_type = build_function_type
93 (type_info_type_node, TYPE_QUAL_CONST)),
95 tinfo_var_id = get_identifier ("__ti");
99 /* FIXME: These identifier prefixes are not set in stone yet. */
100 tinfo_decl_id = get_identifier ("__ti");
101 tinfo_var_id = get_identifier ("__tn");
102 tinfo_decl_type = build_qualified_type
103 (type_info_type_node, TYPE_QUAL_CONST);
107 /* Given a pointer to an object with at least one virtual table
108 pointer somewhere, return a pointer to a possible sub-object that
109 has a virtual table pointer in it that is the vtable parent for
113 build_headof_sub (exp)
116 tree type = TREE_TYPE (TREE_TYPE (exp));
117 tree basetype = CLASSTYPE_RTTI (type);
118 tree binfo = get_binfo (basetype, type, 0);
120 exp = convert_pointer_to_real (binfo, exp);
124 /* Given the expression EXP of type `class *', return the head of the
125 object pointed to by EXP with type cv void*, if the class has any
126 virtual functions (TYPE_POLYMORPHIC_P), else just return the
133 tree type = TREE_TYPE (exp);
138 my_friendly_assert (TREE_CODE (type) == POINTER_TYPE, 20000112);
139 type = TREE_TYPE (type);
141 if (!TYPE_POLYMORPHIC_P (type))
143 if (CLASSTYPE_COM_INTERFACE (type))
145 cp_error ("RTTI not supported for COM interface type `%T'", type);
146 return error_mark_node;
149 /* If we don't have rtti stuff, get to a sub-object that does. */
150 if (!CLASSTYPE_VFIELDS (TREE_TYPE (TREE_TYPE (exp))))
151 exp = build_headof_sub (exp);
153 /* We use this a couple of times below, protect it. */
154 exp = save_expr (exp);
156 /* Under the new ABI, the offset-to-top field is at index -2 from
158 if (new_abi_rtti_p ())
159 index = build_int_2 (-2, -1);
160 /* But under the old ABI, it is at offset zero. */
162 index = integer_zero_node;
164 aref = build_vtbl_ref (build_indirect_ref (exp, NULL_PTR), index);
166 if (flag_vtable_thunks)
169 offset = build_component_ref (aref, delta_identifier, NULL_TREE, 0);
171 type = build_qualified_type (ptr_type_node,
172 CP_TYPE_QUALS (TREE_TYPE (exp)));
173 return build (PLUS_EXPR, type, exp,
174 cp_convert (ptrdiff_type_node, offset));
177 /* Get a bad_cast node for the program to throw...
179 See libstdc++/exception.cc for __throw_bad_cast */
184 tree fn = get_identifier (flag_new_abi
187 if (IDENTIFIER_GLOBAL_VALUE (fn))
188 fn = IDENTIFIER_GLOBAL_VALUE (fn);
190 fn = push_throw_library_fn (fn, build_function_type (ptr_type_node,
193 return build_call (fn, NULL_TREE);
199 tree fn = get_identifier (flag_new_abi
201 : "__throw_bad_typeid");
202 if (IDENTIFIER_GLOBAL_VALUE (fn))
203 fn = IDENTIFIER_GLOBAL_VALUE (fn);
206 tree t = build_qualified_type (type_info_type_node, TYPE_QUAL_CONST);
207 t = build_function_type (build_reference_type (t), void_list_node);
208 fn = push_throw_library_fn (fn, t);
211 return build_call (fn, NULL_TREE);
214 /* Return a pointer to type_info function associated with the expression EXP.
215 If EXP is a reference to a polymorphic class, return the dynamic type;
216 otherwise return the static type of the expression. */
219 get_tinfo_decl_dynamic (exp)
224 if (exp == error_mark_node)
225 return error_mark_node;
227 type = TREE_TYPE (exp);
229 /* peel back references, so they match. */
230 if (TREE_CODE (type) == REFERENCE_TYPE)
231 type = TREE_TYPE (type);
233 /* Peel off cv qualifiers. */
234 type = TYPE_MAIN_VARIANT (type);
236 if (!VOID_TYPE_P (type))
237 type = complete_type_or_else (type, exp);
240 return error_mark_node;
242 /* If exp is a reference to polymorphic type, get the real type_info. */
243 if (TYPE_POLYMORPHIC_P (type) && ! resolves_to_fixed_type_p (exp, 0))
245 /* build reference to type_info from vtable. */
250 error ("taking dynamic typeid of object with -fno-rtti");
251 if (CLASSTYPE_COM_INTERFACE (type))
253 cp_error ("RTTI not supported for COM interface type `%T'", type);
254 return error_mark_node;
257 /* If we don't have rtti stuff, get to a sub-object that does. */
258 if (! CLASSTYPE_VFIELDS (type))
260 exp = build_unary_op (ADDR_EXPR, exp, 0);
261 exp = build_headof_sub (exp);
262 exp = build_indirect_ref (exp, NULL_PTR);
265 /* The RTTI information is always in the vtable, but it's at
266 different indices depending on the ABI. */
267 if (new_abi_rtti_p ())
268 index = minus_one_node;
269 else if (flag_vtable_thunks)
270 index = integer_one_node;
272 index = integer_zero_node;
273 t = build_vfn_ref ((tree *) 0, exp, index);
274 TREE_TYPE (t) = build_pointer_type (tinfo_decl_type);
278 /* otherwise return the type_info for the static type of the expr. */
279 exp = get_tinfo_decl (TYPE_MAIN_VARIANT (type));
280 return build_unary_op (ADDR_EXPR, exp, 0);
287 tree cond = NULL_TREE;
292 error ("cannot use typeid with -fno-rtti");
293 return error_mark_node;
296 if (!COMPLETE_TYPE_P (type_info_type_node))
298 error ("must #include <typeinfo> before using typeid");
299 return error_mark_node;
302 if (processing_template_decl)
303 return build_min_nt (TYPEID_EXPR, exp);
305 if (TREE_CODE (exp) == INDIRECT_REF
306 && TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == POINTER_TYPE
307 && TYPE_POLYMORPHIC_P (TREE_TYPE (exp))
308 && ! resolves_to_fixed_type_p (exp, &nonnull)
311 exp = stabilize_reference (exp);
312 cond = cp_convert (boolean_type_node, TREE_OPERAND (exp, 0));
315 exp = get_tinfo_decl_dynamic (exp);
317 if (exp == error_mark_node)
318 return error_mark_node;
320 exp = tinfo_from_decl (exp);
324 tree bad = throw_bad_typeid ();
326 exp = build (COND_EXPR, TREE_TYPE (exp), cond, exp, bad);
329 return convert_from_reference (exp);
336 tree tname = build_overload_with_type (tinfo_var_id, type);
340 my_friendly_assert (!new_abi_rtti_p (), 20000118);
341 if (IDENTIFIER_GLOBAL_VALUE (tname))
342 return IDENTIFIER_GLOBAL_VALUE (tname);
344 /* Figure out how much space we need to allocate for the type_info object.
345 If our struct layout or the type_info classes are changed, this will
346 need to be modified. */
347 if (TYPE_QUALS (type) != TYPE_UNQUALIFIED)
348 size = 3 * POINTER_SIZE + INT_TYPE_SIZE;
349 else if (TREE_CODE (type) == POINTER_TYPE
350 && ! (TREE_CODE (TREE_TYPE (type)) == OFFSET_TYPE
351 || TREE_CODE (TREE_TYPE (type)) == METHOD_TYPE))
352 size = 3 * POINTER_SIZE;
353 else if (IS_AGGR_TYPE (type))
355 if (CLASSTYPE_N_BASECLASSES (type) == 0)
356 size = 2 * POINTER_SIZE;
357 else if (! TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
359 (TREE_VEC_ELT (TYPE_BINFO_BASETYPES (type), 0))))
360 size = 3 * POINTER_SIZE;
362 size = 3 * POINTER_SIZE + TYPE_PRECISION (sizetype);
365 size = 2 * POINTER_SIZE;
367 /* The type for a character array of the appropriate size. */
368 arrtype = build_cplus_array_type
369 (unsigned_char_type_node,
370 build_index_type (size_int (size / BITS_PER_UNIT - 1)));
372 return declare_global_var (tname, arrtype);
375 /* Generate the NTBS name of a type. */
384 name = mangle_type_string (type);
386 name = build_overload_name (type, 1, 1);
387 name_string = combine_strings (build_string (strlen (name) + 1, name));
391 /* Returns a decl for a function or variable which can be used to obtain a
392 type_info object for TYPE. The old-abi uses functions, the new-abi
393 uses the type_info object directly. You can take the address of the
394 returned decl, to save the decl. To use the decl call
395 tinfo_from_decl. You must arrange that the decl is mark_used, if
396 actually use it --- decls in vtables are only used if the vtable is
400 get_tinfo_decl (type)
406 if (TREE_CODE (type) == OFFSET_TYPE)
407 type = TREE_TYPE (type);
408 if (TREE_CODE (type) == METHOD_TYPE)
409 type = build_function_type (TREE_TYPE (type),
410 TREE_CHAIN (TYPE_ARG_TYPES (type)));
413 name = mangle_typeinfo_for_type (type);
415 name = build_overload_with_type (tinfo_decl_id, type);
417 d = IDENTIFIER_GLOBAL_VALUE (name);
420 else if (!new_abi_rtti_p ())
422 /* The tinfo decl is a function returning a reference to the
424 d = push_library_fn (name, tinfo_decl_type);
425 DECL_NOT_REALLY_EXTERN (d) = 1;
426 SET_DECL_TINFO_FN_P (d);
427 TREE_TYPE (name) = type;
432 /* The tinfo decl is the type_info object itself. We make all
433 tinfo objects look as type_info, even though they will end up
434 being a subclass of that when emitted. This means the we'll
435 erroneously think we know the dynamic type -- be careful in the
437 d = build_lang_decl (VAR_DECL, name, tinfo_decl_type);
439 DECL_ARTIFICIAL (d) = 1;
440 DECL_ALIGN (d) = TYPE_ALIGN (ptr_type_node);
441 DECL_USER_ALIGN (d) = 0;
442 TREE_READONLY (d) = 1;
444 DECL_EXTERNAL (d) = 1;
447 DECL_ASSEMBLER_NAME (d) = DECL_NAME (d);
448 cp_finish_decl (d, NULL_TREE, NULL_TREE, 0);
450 pushdecl_top_level (d);
451 /* Remember the type it is for. */
452 TREE_TYPE (name) = type;
453 TREE_USED (name) = 1;
458 /* Given an expr produced by get_tinfo_decl, return an expr which
459 produces a reference to the type_info object. */
462 tinfo_from_decl (expr)
467 if (!new_abi_rtti_p ())
468 t = build_call (expr, NULL_TREE);
469 else if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
470 t = build_indirect_ref (expr, NULL);
483 t = get_tinfo_decl (type);
484 t = tinfo_from_decl (t);
485 return convert_from_reference (t);
488 /* Return the type_info object for TYPE. */
494 if (type == error_mark_node)
495 return error_mark_node;
497 if (!COMPLETE_TYPE_P (type_info_type_node))
499 error ("must #include <typeinfo> before using typeid");
500 return error_mark_node;
503 if (processing_template_decl)
504 return build_min_nt (TYPEID_EXPR, type);
506 /* If the type of the type-id is a reference type, the result of the
507 typeid expression refers to a type_info object representing the
509 if (TREE_CODE (type) == REFERENCE_TYPE)
510 type = TREE_TYPE (type);
512 /* The top-level cv-qualifiers of the lvalue expression or the type-id
513 that is the operand of typeid are always ignored. */
514 type = TYPE_MAIN_VARIANT (type);
516 if (!VOID_TYPE_P (type))
517 type = complete_type_or_else (type, NULL_TREE);
520 return error_mark_node;
522 return get_typeid_1 (type);
525 /* Check whether TEST is null before returning RESULT. If TEST is used in
526 RESULT, it must have previously had a save_expr applied to it. */
529 ifnonnull (test, result)
532 return build (COND_EXPR, TREE_TYPE (result),
533 build (EQ_EXPR, boolean_type_node, test, integer_zero_node),
534 cp_convert (TREE_TYPE (result), integer_zero_node),
538 /* Generate the constant expression describing where direct base BINFO
539 appears within the PARENT. How to interpret this expression depends on
540 details of the ABI, which the runtime must be aware of. */
543 get_base_offset (binfo, parent)
547 if (! TREE_VIA_VIRTUAL (binfo))
548 return BINFO_OFFSET (binfo);
549 else if (! vbase_offsets_in_vtable_p ())
555 FORMAT_VBASE_NAME (name, BINFO_TYPE (binfo));
556 field = lookup_field (parent, get_identifier (name), 0, 0);
557 result = byte_position (field);
559 if (DECL_CONTEXT (field) != parent)
561 /* The vbase pointer might be in a non-virtual base of PARENT.
562 * Adjust for the offset of that base in PARENT. */
565 get_base_distance (DECL_CONTEXT (field), parent, -1, &path);
566 result = build (PLUS_EXPR, TREE_TYPE (result),
567 result, BINFO_OFFSET (path));
568 result = fold (result);
573 /* Under the new ABI, we store the vtable offset at which
574 the virtual base offset can be found. */
575 return convert (sizetype,
576 BINFO_VPTR_FIELD (binfo_for_vbase (BINFO_TYPE (binfo),
581 /* Execute a dynamic cast, as described in section 5.2.6 of the 9/93 working
585 build_dynamic_cast_1 (type, expr)
588 enum tree_code tc = TREE_CODE (type);
589 tree exprtype = TREE_TYPE (expr);
591 tree old_expr = expr;
592 const char *errstr = NULL;
594 /* T shall be a pointer or reference to a complete class type, or
595 `pointer to cv void''. */
599 if (TREE_CODE (TREE_TYPE (type)) == VOID_TYPE)
602 if (! IS_AGGR_TYPE (TREE_TYPE (type)))
604 errstr = "target is not pointer or reference to class";
607 if (!COMPLETE_TYPE_P (complete_type (TREE_TYPE (type))))
609 errstr = "target is not pointer or reference to complete type";
615 errstr = "target is not pointer or reference";
619 if (TREE_CODE (expr) == OFFSET_REF)
621 expr = resolve_offset_ref (expr);
622 exprtype = TREE_TYPE (expr);
625 if (tc == POINTER_TYPE)
626 expr = convert_from_reference (expr);
627 else if (TREE_CODE (exprtype) != REFERENCE_TYPE)
629 /* Apply trivial conversion T -> T& for dereferenced ptrs. */
630 exprtype = build_reference_type (exprtype);
631 expr = convert_to_reference (exprtype, expr, CONV_IMPLICIT,
632 LOOKUP_NORMAL, NULL_TREE);
635 exprtype = TREE_TYPE (expr);
637 if (tc == POINTER_TYPE)
639 /* If T is a pointer type, v shall be an rvalue of a pointer to
640 complete class type, and the result is an rvalue of type T. */
642 if (TREE_CODE (exprtype) != POINTER_TYPE)
644 errstr = "source is not a pointer";
647 if (! IS_AGGR_TYPE (TREE_TYPE (exprtype)))
649 errstr = "source is not a pointer to class";
652 if (!COMPLETE_TYPE_P (complete_type (TREE_TYPE (exprtype))))
654 errstr = "source is a pointer to incomplete type";
660 /* T is a reference type, v shall be an lvalue of a complete class
661 type, and the result is an lvalue of the type referred to by T. */
663 if (! IS_AGGR_TYPE (TREE_TYPE (exprtype)))
665 errstr = "source is not of class type";
668 if (!COMPLETE_TYPE_P (complete_type (TREE_TYPE (exprtype))))
670 errstr = "source is of incomplete class type";
676 /* The dynamic_cast operator shall not cast away constness. */
677 if (!at_least_as_qualified_p (TREE_TYPE (type),
678 TREE_TYPE (exprtype)))
680 errstr = "conversion casts away constness";
684 /* If *type is an unambiguous accessible base class of *exprtype,
685 convert statically. */
690 distance = get_base_distance (TREE_TYPE (type), TREE_TYPE (exprtype), 1,
695 cp_error ("dynamic_cast from `%T' to ambiguous base class `%T'",
696 TREE_TYPE (exprtype), TREE_TYPE (type));
697 return error_mark_node;
701 cp_error ("dynamic_cast from `%T' to private base class `%T'",
702 TREE_TYPE (exprtype), TREE_TYPE (type));
703 return error_mark_node;
708 expr = build_vbase_path (PLUS_EXPR, type, expr, path, 0);
709 if (TREE_CODE (exprtype) == POINTER_TYPE)
710 expr = non_lvalue (expr);
715 /* Otherwise *exprtype must be a polymorphic class (have a vtbl). */
716 if (TYPE_POLYMORPHIC_P (TREE_TYPE (exprtype)))
719 /* if TYPE is `void *', return pointer to complete object. */
720 if (tc == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (type)))
722 /* if b is an object, dynamic_cast<void *>(&b) == (void *)&b. */
723 if (TREE_CODE (expr) == ADDR_EXPR
724 && TREE_CODE (TREE_OPERAND (expr, 0)) == VAR_DECL
725 && TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == RECORD_TYPE)
726 return build1 (NOP_EXPR, type, expr);
728 /* Since expr is used twice below, save it. */
729 expr = save_expr (expr);
731 expr1 = build_headof (expr);
732 if (TREE_TYPE (expr1) != type)
733 expr1 = build1 (NOP_EXPR, type, expr1);
734 return ifnonnull (expr, expr1);
739 tree result, td2, td3, elems;
740 tree static_type, target_type, boff;
742 /* If we got here, we can't convert statically. Therefore,
743 dynamic_cast<D&>(b) (b an object) cannot succeed. */
744 if (tc == REFERENCE_TYPE)
746 if (TREE_CODE (old_expr) == VAR_DECL
747 && TREE_CODE (TREE_TYPE (old_expr)) == RECORD_TYPE)
749 tree expr = throw_bad_cast ();
750 cp_warning ("dynamic_cast of `%#D' to `%#T' can never succeed",
752 /* Bash it to the expected type. */
753 TREE_TYPE (expr) = type;
757 /* Ditto for dynamic_cast<D*>(&b). */
758 else if (TREE_CODE (expr) == ADDR_EXPR)
760 tree op = TREE_OPERAND (expr, 0);
761 if (TREE_CODE (op) == VAR_DECL
762 && TREE_CODE (TREE_TYPE (op)) == RECORD_TYPE)
764 cp_warning ("dynamic_cast of `%#D' to `%#T' can never succeed",
766 retval = build_int_2 (0, 0);
767 TREE_TYPE (retval) = type;
772 target_type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
773 static_type = TYPE_MAIN_VARIANT (TREE_TYPE (exprtype));
774 td2 = build_unary_op (ADDR_EXPR, get_tinfo_decl (target_type), 0);
775 td3 = build_unary_op (ADDR_EXPR, get_tinfo_decl (static_type), 0);
777 /* Determine how T and V are related. */
778 boff = get_dynamic_cast_base_type (static_type, target_type);
780 /* Since expr is used twice below, save it. */
781 expr = save_expr (expr);
784 if (tc == REFERENCE_TYPE)
785 expr1 = build_unary_op (ADDR_EXPR, expr1, 0);
787 if (!new_abi_rtti_p ())
789 tree expr2 = build_headof (expr1);
792 if (tc == POINTER_TYPE)
793 td1 = build_indirect_ref (td1, NULL_PTR);
794 td1 = get_tinfo_decl_dynamic (td1);
797 (NULL_TREE, td1, tree_cons
798 (NULL_TREE, td2, tree_cons
799 (NULL_TREE, boff, tree_cons
800 (NULL_TREE, expr2, tree_cons
801 (NULL_TREE, td3, tree_cons
802 (NULL_TREE, expr1, NULL_TREE))))));
806 (NULL_TREE, expr1, tree_cons
807 (NULL_TREE, td3, tree_cons
808 (NULL_TREE, td2, tree_cons
809 (NULL_TREE, boff, NULL_TREE))));
811 dcast_fn = dynamic_cast_node;
816 tree ns = new_abi_rtti_p () ? abi_node : global_namespace;
819 push_nested_namespace (ns);
820 if (!new_abi_rtti_p ())
822 tinfo_ptr = build_pointer_type (tinfo_decl_type);
823 name = "__dynamic_cast_2";
825 (NULL_TREE, tinfo_ptr, tree_cons
826 (NULL_TREE, tinfo_ptr, tree_cons
827 (NULL_TREE, integer_type_node, tree_cons
828 (NULL_TREE, ptr_type_node, tree_cons
829 (NULL_TREE, tinfo_ptr, tree_cons
830 (NULL_TREE, ptr_type_node, void_list_node))))));
834 tinfo_ptr = xref_tag (class_type_node,
835 get_identifier ("__class_type_info"),
838 tinfo_ptr = build_pointer_type
839 (build_qualified_type
840 (tinfo_ptr, TYPE_QUAL_CONST));
841 name = "__dynamic_cast";
843 (NULL_TREE, const_ptr_type_node, tree_cons
844 (NULL_TREE, tinfo_ptr, tree_cons
845 (NULL_TREE, tinfo_ptr, tree_cons
846 (NULL_TREE, ptrdiff_type_node, void_list_node))));
848 tmp = build_function_type (ptr_type_node, tmp);
849 dcast_fn = build_library_fn_ptr (name, tmp);
850 pop_nested_namespace (ns);
851 dynamic_cast_node = dcast_fn;
853 result = build_call (dcast_fn, elems);
855 if (tc == REFERENCE_TYPE)
857 tree bad = throw_bad_cast ();
859 result = save_expr (result);
860 return build (COND_EXPR, type, result, result, bad);
863 /* Now back to the type we want from a void*. */
864 result = cp_convert (type, result);
865 return ifnonnull (expr, result);
869 errstr = "source type is not polymorphic";
872 cp_error ("cannot dynamic_cast `%E' (of type `%#T') to type `%#T' (%s)",
873 expr, exprtype, type, errstr);
874 return error_mark_node;
878 build_dynamic_cast (type, expr)
881 if (type == error_mark_node || expr == error_mark_node)
882 return error_mark_node;
884 if (processing_template_decl)
885 return build_min (DYNAMIC_CAST_EXPR, type, expr);
887 return convert_from_reference (build_dynamic_cast_1 (type, expr));
890 /* Build and initialize various sorts of descriptors. Every descriptor
891 node has a name associated with it (the name created by mangling).
892 For this reason, we use the identifier as our access to the __*_desc
893 nodes, instead of sticking them directly in the types. Otherwise we
894 would burden all built-in types (and pointer types) with slots that
895 we don't necessarily want to use.
897 For each descriptor we build, we build a variable that contains
898 the descriptor's information. When we need this info at runtime,
899 all we need is access to these variables.
901 Note: these constructors always return the address of the descriptor
902 info, since that is simplest for their mutual interaction. */
904 /* Build an initializer for a __si_type_info node. */
907 expand_si_desc (tdecl, type)
912 tree name_string = tinfo_name (type);
914 type = BINFO_TYPE (TREE_VEC_ELT (TYPE_BINFO_BASETYPES (type), 0));
915 finish_expr_stmt (get_typeid_1 (type));
916 t = decay_conversion (get_tinfo_var (type));
918 (NULL_TREE, decay_conversion (tdecl), tree_cons
919 (NULL_TREE, decay_conversion (name_string), tree_cons
920 (NULL_TREE, t, NULL_TREE)));
922 fn = get_identifier ("__rtti_si");
923 if (IDENTIFIER_GLOBAL_VALUE (fn))
924 fn = IDENTIFIER_GLOBAL_VALUE (fn);
929 (NULL_TREE, ptr_type_node, tree_cons
930 (NULL_TREE, const_string_type_node, tree_cons
931 (NULL_TREE, build_pointer_type (type_info_type_node),
933 fn = push_void_library_fn (fn, tmp);
936 fn = build_call (fn, elems);
937 finish_expr_stmt (fn);
940 /* Build an initializer for a __class_type_info node. */
943 expand_class_desc (tdecl, type)
950 int i = CLASSTYPE_N_BASECLASSES (type);
952 tree binfos = TYPE_BINFO_BASETYPES (type);
953 tree base, elems, access, offset, isvir;
954 tree elt, elts = NULL_TREE;
956 if (base_desc_type_node == NULL_TREE)
960 /* A reasonably close approximation of __class_type_info::base_info */
962 base_desc_type_node = make_aggr_type (RECORD_TYPE);
964 /* Actually const __user_type_info * */
965 fields [0] = build_decl
966 (FIELD_DECL, NULL_TREE,
967 build_pointer_type (build_qualified_type
968 (type_info_type_node,
970 fields [1] = build_decl
971 (FIELD_DECL, NULL_TREE,
972 flag_new_abi ? intSI_type_node : unsigned_intSI_type_node);
973 DECL_BIT_FIELD (fields[1]) = 1;
974 DECL_SIZE (fields[1]) = bitsize_int (29);
976 fields [2] = build_decl (FIELD_DECL, NULL_TREE, boolean_type_node);
977 DECL_BIT_FIELD (fields[2]) = 1;
978 DECL_SIZE (fields[2]) = bitsize_one_node;
980 /* Actually enum access */
981 fields [3] = build_decl (FIELD_DECL, NULL_TREE, integer_type_node);
982 DECL_BIT_FIELD (fields[3]) = 1;
983 DECL_SIZE (fields[3]) = bitsize_int (2);
985 finish_builtin_type (base_desc_type_node, "__base_info", fields,
991 tree binfo = TREE_VEC_ELT (binfos, i);
993 finish_expr_stmt (get_typeid_1 (BINFO_TYPE (binfo)));
994 base = decay_conversion (get_tinfo_var (BINFO_TYPE (binfo)));
995 offset = get_base_offset (binfo, type);
997 if (TREE_VIA_PUBLIC (binfo))
998 access = access_public_node;
999 else if (TREE_VIA_PROTECTED (binfo))
1000 access = access_protected_node;
1002 access = access_private_node;
1003 if (TREE_VIA_VIRTUAL (binfo))
1004 isvir = boolean_true_node;
1006 isvir = boolean_false_node;
1009 (CONSTRUCTOR, base_desc_type_node, NULL_TREE, tree_cons
1010 (NULL_TREE, base, tree_cons
1011 (NULL_TREE, offset, tree_cons
1012 (NULL_TREE, isvir, tree_cons
1013 (NULL_TREE, access, NULL_TREE)))));
1014 TREE_HAS_CONSTRUCTOR (elt) = TREE_CONSTANT (elt) = TREE_STATIC (elt) = 1;
1015 elts = tree_cons (NULL_TREE, elt, elts);
1019 name_string = tinfo_name (type);
1022 tree arrtype = build_array_type (base_desc_type_node, NULL_TREE);
1023 elts = build (CONSTRUCTOR, arrtype, NULL_TREE, elts);
1024 TREE_HAS_CONSTRUCTOR (elts) = TREE_CONSTANT (elts)
1025 = TREE_STATIC (elts) = 1;
1026 complete_array_type (arrtype, elts, 1);
1030 (NULL_TREE, decay_conversion (tdecl), tree_cons
1031 (NULL_TREE, decay_conversion (name_string), tree_cons
1032 (NULL_TREE, decay_conversion (elts), tree_cons
1033 (NULL_TREE, cp_convert (sizetype, build_int_2 (base_cnt, 0)),
1036 fn = get_identifier ("__rtti_class");
1037 if (IDENTIFIER_GLOBAL_VALUE (fn))
1038 fn = IDENTIFIER_GLOBAL_VALUE (fn);
1042 (NULL_TREE, ptr_type_node, tree_cons
1043 (NULL_TREE, const_string_type_node, tree_cons
1044 (NULL_TREE, build_pointer_type (base_desc_type_node), tree_cons
1045 (NULL_TREE, sizetype, void_list_node))));
1047 fn = push_void_library_fn (fn, tmp);
1050 fn = build_call (fn, elems);
1051 finish_expr_stmt (fn);
1054 /* Build an initializer for a __pointer_type_info node. */
1057 expand_ptr_desc (tdecl, type)
1062 tree name_string = tinfo_name (type);
1064 type = TREE_TYPE (type);
1065 finish_expr_stmt (get_typeid_1 (type));
1066 t = decay_conversion (get_tinfo_var (type));
1068 (NULL_TREE, decay_conversion (tdecl), tree_cons
1069 (NULL_TREE, decay_conversion (name_string), tree_cons
1070 (NULL_TREE, t, NULL_TREE)));
1072 fn = get_identifier ("__rtti_ptr");
1073 if (IDENTIFIER_GLOBAL_VALUE (fn))
1074 fn = IDENTIFIER_GLOBAL_VALUE (fn);
1079 (NULL_TREE, ptr_type_node, tree_cons
1080 (NULL_TREE, const_string_type_node, tree_cons
1081 (NULL_TREE, build_pointer_type (type_info_type_node),
1083 fn = push_void_library_fn (fn, tmp);
1086 fn = build_call (fn, elems);
1087 finish_expr_stmt (fn);
1090 /* Build an initializer for a __attr_type_info node. */
1093 expand_attr_desc (tdecl, type)
1098 tree name_string = tinfo_name (type);
1099 tree attrval = build_int_2 (TYPE_QUALS (type), 0);
1101 finish_expr_stmt (get_typeid_1 (TYPE_MAIN_VARIANT (type)));
1102 t = decay_conversion (get_tinfo_var (TYPE_MAIN_VARIANT (type)));
1104 (NULL_TREE, decay_conversion (tdecl), tree_cons
1105 (NULL_TREE, decay_conversion (name_string), tree_cons
1106 (NULL_TREE, attrval, tree_cons (NULL_TREE, t, NULL_TREE))));
1108 fn = get_identifier ("__rtti_attr");
1109 if (IDENTIFIER_GLOBAL_VALUE (fn))
1110 fn = IDENTIFIER_GLOBAL_VALUE (fn);
1115 (NULL_TREE, ptr_type_node, tree_cons
1116 (NULL_TREE, const_string_type_node, tree_cons
1117 (NULL_TREE, integer_type_node, tree_cons
1118 (NULL_TREE, build_pointer_type (type_info_type_node),
1120 fn = push_void_library_fn (fn, tmp);
1123 fn = build_call (fn, elems);
1124 finish_expr_stmt (fn);
1127 /* Build an initializer for a type_info node that just has a name. */
1130 expand_generic_desc (tdecl, type, fnname)
1135 tree name_string = tinfo_name (type);
1136 tree elems = tree_cons
1137 (NULL_TREE, decay_conversion (tdecl), tree_cons
1138 (NULL_TREE, decay_conversion (name_string), NULL_TREE));
1140 tree fn = get_identifier (fnname);
1141 if (IDENTIFIER_GLOBAL_VALUE (fn))
1142 fn = IDENTIFIER_GLOBAL_VALUE (fn);
1147 (NULL_TREE, ptr_type_node, tree_cons
1148 (NULL_TREE, const_string_type_node, void_list_node));
1149 fn = push_void_library_fn (fn, tmp);
1152 fn = build_call (fn, elems);
1153 finish_expr_stmt (fn);
1156 /* Generate the code for a type_info initialization function.
1157 Note that we take advantage of the passage
1159 5.2.7 Type identification [expr.typeid]
1161 Whether or not the destructor is called for the type_info object at the
1162 end of the program is unspecified.
1164 and don't bother to arrange for these objects to be destroyed. It
1165 doesn't matter, anyway, since the destructors don't do anything.
1167 This must only be called from toplevel (i.e. from finish_file)! */
1170 synthesize_tinfo_fn (fndecl)
1173 tree type = TREE_TYPE (DECL_NAME (fndecl));
1174 tree tmp, addr, tdecl;
1179 my_friendly_assert (!new_abi_rtti_p (), 20000118);
1182 import_export_decl (fndecl);
1183 if (DECL_REALLY_EXTERN (fndecl))
1187 /* Declare the static typeinfo variable. */
1188 tdecl = get_tinfo_var (type);
1189 DECL_EXTERNAL (tdecl) = 0;
1190 TREE_STATIC (tdecl) = 1;
1191 DECL_COMMON (tdecl) = 1;
1192 TREE_USED (tdecl) = 1;
1193 DECL_ALIGN (tdecl) = TYPE_ALIGN (ptr_type_node);
1194 DECL_USER_ALIGN (tdecl) = 0;
1195 cp_finish_decl (tdecl, NULL_TREE, NULL_TREE, 0);
1197 /* Begin processing the function. */
1198 start_function (NULL_TREE, fndecl, NULL_TREE,
1199 SF_DEFAULT | SF_PRE_PARSED);
1200 DECL_DEFER_OUTPUT (fndecl) = 1;
1203 /* Begin the body of the function. */
1204 compound_stmt = begin_compound_stmt (/*has_no_scope=*/0);
1206 /* For convenience, we save away the address of the static
1208 addr = decay_conversion (tdecl);
1210 /* If the first word of the array (the vtable) is non-zero, we've already
1211 initialized the object, so don't do it again. */
1212 if_stmt = begin_if_stmt ();
1213 tmp = cp_convert (build_pointer_type (ptr_type_node), addr);
1214 tmp = build_indirect_ref (tmp, 0);
1215 tmp = cp_build_binary_op (EQ_EXPR, tmp, integer_zero_node);
1216 finish_if_stmt_cond (tmp, if_stmt);
1217 then_clause = begin_compound_stmt (/*has_no_scope=*/0);
1219 if (TREE_CODE (type) == FUNCTION_TYPE)
1220 expand_generic_desc (tdecl, type, "__rtti_func");
1221 else if (TREE_CODE (type) == ARRAY_TYPE)
1222 expand_generic_desc (tdecl, type, "__rtti_array");
1223 else if (TYPE_QUALS (type) != TYPE_UNQUALIFIED)
1224 expand_attr_desc (tdecl, type);
1225 else if (TREE_CODE (type) == POINTER_TYPE)
1227 if (TREE_CODE (TREE_TYPE (type)) == OFFSET_TYPE)
1228 expand_generic_desc (tdecl, type, "__rtti_ptmd");
1229 else if (TREE_CODE (TREE_TYPE (type)) == METHOD_TYPE)
1230 expand_generic_desc (tdecl, type, "__rtti_ptmf");
1232 expand_ptr_desc (tdecl, type);
1234 else if (TYPE_PTRMEMFUNC_P (type))
1235 expand_generic_desc (tdecl, type, "__rtti_ptmf");
1236 else if (IS_AGGR_TYPE (type))
1238 if (CLASSTYPE_N_BASECLASSES (type) == 0)
1239 expand_generic_desc (tdecl, type, "__rtti_user");
1240 else if (! TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
1242 (TREE_VEC_ELT (TYPE_BINFO_BASETYPES (type), 0))))
1243 expand_si_desc (tdecl, type);
1245 expand_class_desc (tdecl, type);
1247 else if (TREE_CODE (type) == ENUMERAL_TYPE)
1248 expand_generic_desc (tdecl, type, "__rtti_user");
1250 my_friendly_abort (252);
1252 finish_compound_stmt (/*has_no_scope=*/0, then_clause);
1253 finish_then_clause (if_stmt);
1256 /* OK, now return the type_info object. */
1257 tmp = cp_convert (build_pointer_type (type_info_type_node), addr);
1258 tmp = build_indirect_ref (tmp, 0);
1259 finish_return_stmt (tmp);
1260 /* Finish the function body. */
1261 finish_compound_stmt (/*has_no_scope=*/0, compound_stmt);
1262 expand_body (finish_function (0));
1265 /* Return the runtime bit mask encoding the qualifiers of TYPE. */
1268 qualifier_flags (type)
1272 /* we want the qualifiers on this type, not any array core, it might have */
1273 int quals = TYPE_QUALS (type);
1275 if (quals & TYPE_QUAL_CONST)
1277 if (quals & TYPE_QUAL_VOLATILE)
1279 if (quals & TYPE_QUAL_RESTRICT)
1284 /* Return non-zero, if the pointer chain TYPE ends at an incomplete type, or
1285 contains a pointer to member of an incomplete class. */
1288 target_incomplete_p (type)
1291 while (TREE_CODE (type) == POINTER_TYPE)
1292 if (TYPE_PTRMEM_P (type))
1294 if (!COMPLETE_TYPE_P (TYPE_PTRMEM_CLASS_TYPE (type)))
1296 type = TYPE_PTRMEM_POINTED_TO_TYPE (type);
1299 type = TREE_TYPE (type);
1300 if (!COMPLETE_OR_VOID_TYPE_P (type))
1306 /* Return a CONSTRUCTOR for the common part of the type_info objects. This
1307 is the vtable pointer and NTBS name. The NTBS name is emitted as a
1308 comdat const char array, so it becomes a unique key for the type. Generate
1309 and emit that VAR_DECL here. (We can't always emit the type_info itself
1310 as comdat, because of pointers to incomplete.) */
1313 tinfo_base_init (desc, target)
1317 tree init = NULL_TREE;
1323 /* Generate the NTBS array variable. */
1324 tree name_type = build_cplus_array_type
1325 (build_qualified_type (char_type_node, TYPE_QUAL_CONST),
1327 tree name_string = tinfo_name (target);
1330 name_name = mangle_typeinfo_for_type (target);
1332 name_name = build_overload_with_type (tinfo_var_id, target);
1333 name_decl = build_lang_decl (VAR_DECL, name_name, name_type);
1335 DECL_ARTIFICIAL (name_decl) = 1;
1336 TREE_READONLY (name_decl) = 1;
1337 TREE_STATIC (name_decl) = 1;
1338 DECL_EXTERNAL (name_decl) = 0;
1339 TREE_PUBLIC (name_decl) = 1;
1340 comdat_linkage (name_decl);
1342 /* The new ABI specifies the external name of the string
1343 containing the type's name. */
1344 DECL_ASSEMBLER_NAME (name_decl)
1345 = mangle_typeinfo_string_for_type (target);
1347 DECL_ASSEMBLER_NAME (name_decl) = DECL_NAME (name_decl);
1348 DECL_INITIAL (name_decl) = name_string;
1349 cp_finish_decl (name_decl, name_string, NULL_TREE, 0);
1352 if (TINFO_VTABLE_DECL (desc))
1354 tree vtbl_ptr = TINFO_VTABLE_DECL (desc);
1355 init = tree_cons (NULL_TREE, vtbl_ptr, init);
1358 init = tree_cons (NULL_TREE, decay_conversion (name_decl), init);
1360 init = build (CONSTRUCTOR, NULL_TREE, NULL_TREE, nreverse (init));
1361 TREE_HAS_CONSTRUCTOR (init) = TREE_CONSTANT (init) = TREE_STATIC (init) = 1;
1362 init = tree_cons (NULL_TREE, init, NULL_TREE);
1367 /* Return the CONSTRUCTOR expr for a type_info of TYPE. DESC provides the
1368 information about the particular type_info derivation, which adds no
1369 additional fields to the type_info base. */
1372 generic_initializer (desc, target)
1376 tree init = tinfo_base_init (desc, target);
1378 init = build (CONSTRUCTOR, NULL_TREE, NULL_TREE, init);
1379 TREE_HAS_CONSTRUCTOR (init) = TREE_CONSTANT (init) = TREE_STATIC (init) = 1;
1383 /* Return the CONSTRUCTOR expr for a type_info of pointer TYPE.
1384 DESC provides information about the particular type_info derivation,
1385 which adds target type and qualifier flags members to the type_info base. */
1388 ptr_initializer (desc, target, non_public_ptr)
1391 int *non_public_ptr;
1393 tree init = tinfo_base_init (desc, target);
1394 tree to = TREE_TYPE (target);
1395 int flags = qualifier_flags (to);
1396 int incomplete = target_incomplete_p (to);
1401 *non_public_ptr = 1;
1403 init = tree_cons (NULL_TREE, build_int_2 (flags, 0), init);
1404 init = tree_cons (NULL_TREE,
1405 build_unary_op (ADDR_EXPR,
1406 get_tinfo_decl (TYPE_MAIN_VARIANT (to)), 0),
1409 init = build (CONSTRUCTOR, NULL_TREE, NULL_TREE, nreverse (init));
1410 TREE_HAS_CONSTRUCTOR (init) = TREE_CONSTANT (init) = TREE_STATIC (init) = 1;
1414 /* Return the CONSTRUCTOR expr for a type_info of pointer to member data TYPE.
1415 DESC provides information about the particular type_info derivation,
1416 which adds class, target type and qualifier flags members to the type_info
1420 ptm_initializer (desc, target, non_public_ptr)
1423 int *non_public_ptr;
1425 tree init = tinfo_base_init (desc, target);
1426 tree to = TYPE_PTRMEM_POINTED_TO_TYPE (target);
1427 tree klass = TYPE_PTRMEM_CLASS_TYPE (target);
1428 int flags = qualifier_flags (to);
1429 int incomplete = target_incomplete_p (to);
1434 *non_public_ptr = 1;
1436 if (!COMPLETE_TYPE_P (klass))
1439 *non_public_ptr = 1;
1441 init = tree_cons (NULL_TREE, build_int_2 (flags, 0), init);
1442 init = tree_cons (NULL_TREE,
1443 build_unary_op (ADDR_EXPR,
1444 get_tinfo_decl (TYPE_MAIN_VARIANT (to)), 0),
1446 init = tree_cons (NULL_TREE,
1447 build_unary_op (ADDR_EXPR, get_tinfo_decl (klass), 0),
1450 init = build (CONSTRUCTOR, NULL_TREE, NULL_TREE, nreverse (init));
1451 TREE_HAS_CONSTRUCTOR (init) = TREE_CONSTANT (init) = TREE_STATIC (init) = 1;
1455 /* Check base BINFO to set hint flags in *DATA, which is really an int.
1456 We use CLASSTYPE_MARKED to tag types we've found as non-virtual bases and
1457 CLASSTYPE_MARKED2 to tag those which are virtual bases. Remember it is
1458 possible for a type to be both a virtual and non-virtual base. */
1461 dfs_class_hint_mark (binfo, data)
1465 tree basetype = BINFO_TYPE (binfo);
1466 int *hint = (int *) data;
1468 if (TREE_VIA_VIRTUAL (binfo))
1470 if (CLASSTYPE_MARKED (basetype))
1472 if (CLASSTYPE_MARKED2 (basetype))
1474 SET_CLASSTYPE_MARKED2 (basetype);
1478 if (CLASSTYPE_MARKED (basetype) || CLASSTYPE_MARKED2 (basetype))
1480 SET_CLASSTYPE_MARKED (basetype);
1482 if (!TREE_VIA_PUBLIC (binfo) && TYPE_BINFO (basetype) != binfo)
1487 /* Clear the base's dfs marks, after searching for duplicate bases. */
1490 dfs_class_hint_unmark (binfo, data)
1492 void *data ATTRIBUTE_UNUSED;
1494 tree basetype = BINFO_TYPE (binfo);
1496 CLEAR_CLASSTYPE_MARKED (basetype);
1497 CLEAR_CLASSTYPE_MARKED2 (basetype);
1501 /* Determine the hint flags describing the features of a class's heirarchy. */
1504 class_hint_flags (type)
1510 dfs_walk (TYPE_BINFO (type), dfs_class_hint_mark, NULL, &hint_flags);
1511 dfs_walk (TYPE_BINFO (type), dfs_class_hint_unmark, NULL, NULL);
1513 for (i = 0; i < CLASSTYPE_N_BASECLASSES (type); ++i)
1515 tree base_binfo = BINFO_BASETYPE (TYPE_BINFO (type), i);
1517 if (TREE_VIA_PUBLIC (base_binfo))
1523 /* Return the CONSTRUCTOR expr for a type_info of class TYPE.
1524 DESC provides information about the particular __class_type_info derivation,
1525 which adds hint flags and TRAIL initializers to the type_info base. */
1528 class_initializer (desc, target, trail)
1533 tree init = tinfo_base_init (desc, target);
1535 TREE_CHAIN (init) = trail;
1536 init = build (CONSTRUCTOR, NULL_TREE, NULL_TREE, init);
1537 TREE_HAS_CONSTRUCTOR (init) = TREE_CONSTANT (init) = TREE_STATIC (init) = 1;
1541 /* Generate a pseudo_type_info VAR_DECL suitable for the supplied
1542 TARGET_TYPE and given the REAL_NAME. This is the structure expected by
1543 the runtime, and therefore has additional fields. If we need not emit a
1544 definition (because the runtime must contain it), return NULL_TREE,
1545 otherwise return the VAR_DECL. */
1548 synthesize_tinfo_var (target_type, real_name)
1552 tree var_init = NULL_TREE;
1553 tree var_type = NULL_TREE;
1556 my_friendly_assert (new_abi_rtti_p (), 20000118);
1558 switch (TREE_CODE (target_type))
1561 if (TYPE_PTRMEM_P (target_type))
1563 var_type = ptm_desc_type_node;
1564 var_init = ptm_initializer (var_type, target_type, &non_public);
1568 int code = TREE_CODE (TREE_TYPE (target_type));
1570 if ((CP_TYPE_QUALS (TREE_TYPE (target_type)) | TYPE_QUAL_CONST)
1572 && (code == INTEGER_TYPE || code == BOOLEAN_TYPE
1573 || code == CHAR_TYPE || code == REAL_TYPE
1574 || code == VOID_TYPE)
1576 /* These are in the runtime. */
1578 var_type = ptr_desc_type_node;
1579 var_init = ptr_initializer (var_type, target_type, &non_public);
1583 var_type = enum_desc_type_node;
1584 var_init = generic_initializer (var_type, target_type);
1587 var_type = func_desc_type_node;
1588 var_init = generic_initializer (var_type, target_type);
1591 var_type = ary_desc_type_node;
1592 var_init = generic_initializer (var_type, target_type);
1596 if (TYPE_PTRMEMFUNC_P (target_type))
1598 var_type = ptm_desc_type_node;
1599 var_init = ptm_initializer (var_type, target_type, &non_public);
1601 else if (!COMPLETE_TYPE_P (target_type))
1603 /* Emit a non-public class_type_info. */
1605 var_type = class_desc_type_node;
1606 var_init = class_initializer (var_type, target_type, NULL_TREE);
1608 else if (!CLASSTYPE_N_BASECLASSES (target_type))
1610 var_type = class_desc_type_node;
1611 var_init = class_initializer (var_type, target_type, NULL_TREE);
1615 /* if this has a single public non-virtual base, it's easier */
1616 tree binfo = TYPE_BINFO (target_type);
1617 int nbases = BINFO_N_BASETYPES (binfo);
1618 tree base_binfos = BINFO_BASETYPES (binfo);
1619 tree base_inits = NULL_TREE;
1620 int is_simple = nbases == 1;
1623 /* Generate the base information initializer. */
1624 for (ix = nbases; ix--;)
1626 tree base_binfo = TREE_VEC_ELT (base_binfos, ix);
1627 tree base_init = NULL_TREE;
1632 if (TREE_VIA_VIRTUAL (base_binfo))
1634 if (TREE_PUBLIC (base_binfo))
1636 tinfo = get_tinfo_decl (BINFO_TYPE (base_binfo));
1637 tinfo = build_unary_op (ADDR_EXPR, tinfo, 0);
1638 offset = get_base_offset (base_binfo, target_type);
1640 /* is it a single public inheritance? */
1641 if (is_simple && flags == 2 && integer_zerop (offset))
1643 base_inits = tree_cons (NULL_TREE, tinfo, NULL_TREE);
1648 /* combine offset and flags into one field */
1649 offset = cp_build_binary_op (LSHIFT_EXPR, offset,
1650 build_int_2 (8, 0));
1651 offset = cp_build_binary_op (BIT_IOR_EXPR, offset,
1652 build_int_2 (flags, 0));
1653 base_init = tree_cons (NULL_TREE, offset, base_init);
1654 base_init = tree_cons (NULL_TREE, tinfo, base_init);
1655 base_init = build (CONSTRUCTOR, NULL_TREE, NULL_TREE, base_init);
1656 base_inits = tree_cons (NULL_TREE, base_init, base_inits);
1660 var_type = si_class_desc_type_node;
1663 int hint = class_hint_flags (target_type);
1665 base_inits = build (CONSTRUCTOR, NULL_TREE, NULL_TREE, base_inits);
1666 base_inits = tree_cons (NULL_TREE, base_inits, NULL_TREE);
1667 /* Prepend the number of bases. */
1668 base_inits = tree_cons (NULL_TREE,
1669 build_int_2 (nbases, 0), base_inits);
1670 /* Prepend the hint flags. */
1671 base_inits = tree_cons (NULL_TREE,
1672 build_int_2 (hint, 0), base_inits);
1673 var_type = get_vmi_pseudo_type_info (nbases);
1675 var_init = class_initializer (var_type, target_type, base_inits);
1684 /* These are guaranteed to be in the runtime. */
1686 var_type = bltn_desc_type_node;
1687 var_init = generic_initializer (var_type, target_type);
1690 my_friendly_abort (20000117);
1694 return create_real_tinfo_var (real_name, TINFO_PSEUDO_TYPE (var_type),
1695 var_init, non_public);
1698 /* Create the real typeinfo variable. NON_PUBLIC indicates that we cannot
1699 make this variable public (comdat). */
1702 create_real_tinfo_var (name, type, init, non_public)
1708 static int count = 0;
1713 sprintf (hidden, "%.*s_%d",
1714 IDENTIFIER_LENGTH (tinfo_decl_id), IDENTIFIER_POINTER (tinfo_decl_id),
1716 hidden_name = get_identifier (hidden);
1718 decl = build_lang_decl (VAR_DECL, hidden_name,
1719 build_qualified_type (type, TYPE_QUAL_CONST));
1720 DECL_ARTIFICIAL (decl) = 1;
1721 TREE_READONLY (decl) = 1;
1722 TREE_STATIC (decl) = 1;
1723 DECL_EXTERNAL (decl) = 0;
1727 TREE_PUBLIC (decl) = 1;
1728 comdat_linkage (decl);
1730 DECL_ASSEMBLER_NAME (decl) = name;
1731 DECL_INITIAL (decl) = init;
1732 cp_finish_decl (decl, init, NULL_TREE, 0);
1733 pushdecl_top_level (decl);
1734 TREE_USED (decl) = 1;
1738 /* Generate the RECORD_TYPE containing the data layout of a type_info
1739 derivative as used by the runtime. This layout must be consistent with
1740 that defined in the runtime support. Also generate the VAR_DECL for the
1741 type's vtable. We explicitly manage the vtable member, and name it for
1742 real type as used in the runtime. The RECORD type has a different name,
1743 to avoid collisions. Return a TREE_LIST who's TINFO_PSEUDO_TYPE
1744 is the generated type and TINFO_VTABLE_DECL is the vtable decl.
1746 REAL_NAME is the runtime's name of the type. Trailing arguments are
1747 additional FIELD_DECL's for the structure. The final argument must be
1751 create_pseudo_type_info VPARAMS((const char *real_name, int ident, ...))
1753 #ifndef ANSI_PROTOTYPES
1754 char const *real_name;
1758 tree real_type, pseudo_type;
1766 VA_START (ap, ident);
1767 #ifndef ANSI_PROTOTYPES
1768 real_name = va_arg (ap, char const *);
1769 ident = va_arg (app, int);
1772 /* Generate the pseudo type name. */
1773 pseudo_name = (char *)alloca (strlen (real_name) + 30);
1774 strcpy (pseudo_name, real_name);
1775 strcat (pseudo_name, "_pseudo");
1777 sprintf (pseudo_name + strlen (pseudo_name), "%d", ident);
1779 /* Get the vtable decl. */
1780 real_type = xref_tag (class_type_node, get_identifier (real_name), 1);
1781 vtable_decl = get_vtable_decl (real_type, /*complete=*/1);
1782 vtable_decl = build_unary_op (ADDR_EXPR, vtable_decl, 0);
1784 /* Under the new ABI, we need to point into the middle of the
1788 vtable_decl = build (PLUS_EXPR,
1789 TREE_TYPE (vtable_decl),
1791 size_binop (MULT_EXPR,
1793 TYPE_SIZE_UNIT (vtable_entry_type)));
1794 TREE_CONSTANT (vtable_decl) = 1;
1797 /* First field is the pseudo type_info base class. */
1798 fields[0] = build_decl (FIELD_DECL, NULL_TREE, ti_desc_type_node);
1800 /* Now add the derived fields. */
1801 for (ix = 0; (field_decl = va_arg (ap, tree));)
1802 fields[++ix] = field_decl;
1804 /* Create the pseudo type. */
1805 pseudo_type = make_aggr_type (RECORD_TYPE);
1806 finish_builtin_type (pseudo_type, pseudo_name, fields, ix, ptr_type_node);
1807 TYPE_HAS_CONSTRUCTOR (pseudo_type) = 1;
1810 result = tree_cons (NULL_TREE, NULL_TREE, NULL_TREE);
1811 TINFO_VTABLE_DECL (result) = vtable_decl;
1812 TINFO_PSEUDO_TYPE (result) = pseudo_type;
1817 /* Return a descriptor for a vmi type with NUM_BASES bases. */
1820 get_vmi_pseudo_type_info (num_bases)
1824 tree array_domain, base_array;
1826 if (TREE_VEC_LENGTH (vmi_class_desc_type_node) <= num_bases)
1829 tree extend = make_tree_vec (num_bases + 5);
1831 for (ix = TREE_VEC_LENGTH (vmi_class_desc_type_node); ix--;)
1832 TREE_VEC_ELT (extend, ix) = TREE_VEC_ELT (vmi_class_desc_type_node, ix);
1833 vmi_class_desc_type_node = extend;
1835 desc = TREE_VEC_ELT (vmi_class_desc_type_node, num_bases);
1840 /* Add number of bases and trailing array of base_class_type_info. */
1841 array_domain = build_index_type (size_int (num_bases));
1842 base_array = build_array_type (base_desc_type_node, array_domain);
1844 push_nested_namespace (abi_node);
1846 desc = create_pseudo_type_info
1847 ("__vmi_class_type_info", num_bases,
1848 build_decl (FIELD_DECL, NULL_TREE, integer_type_node),
1849 build_decl (FIELD_DECL, NULL_TREE, integer_type_node),
1850 build_decl (FIELD_DECL, NULL_TREE, base_array),
1853 pop_nested_namespace (abi_node);
1855 TREE_VEC_ELT (vmi_class_desc_type_node, num_bases) = desc;
1859 /* Make sure the required builtin types exist for generating the type_info
1860 varable definitions. */
1863 create_tinfo_types ()
1867 if (bltn_desc_type_node)
1869 push_nested_namespace (abi_node);
1871 ptr_type_info = build_pointer_type
1872 (build_qualified_type
1873 (type_info_type_node, TYPE_QUAL_CONST));
1875 /* Create the internal type_info structure. This is used as a base for
1876 the other structures. */
1880 ti_desc_type_node = make_aggr_type (RECORD_TYPE);
1881 fields[0] = build_decl (FIELD_DECL, NULL_TREE, const_ptr_type_node);
1882 fields[1] = build_decl (FIELD_DECL, NULL_TREE, const_string_type_node);
1883 finish_builtin_type (ti_desc_type_node, "__type_info_pseudo",
1884 fields, 1, ptr_type_node);
1885 TYPE_HAS_CONSTRUCTOR (ti_desc_type_node) = 1;
1888 /* Fundamental type_info */
1889 bltn_desc_type_node = create_pseudo_type_info
1890 ("__fundamental_type_info", 0,
1893 /* Array, function and enum type_info. No additional fields. */
1894 ary_desc_type_node = create_pseudo_type_info
1895 ("__array_type_info", 0,
1897 func_desc_type_node = create_pseudo_type_info
1898 ("__function_type_info", 0,
1900 enum_desc_type_node = create_pseudo_type_info
1901 ("__enum_type_info", 0,
1904 /* Class type_info. Add a flags field. */
1905 class_desc_type_node = create_pseudo_type_info
1906 ("__class_type_info", 0,
1909 /* Single public non-virtual base class. Add pointer to base class.
1910 This is really a descendant of __class_type_info. */
1911 si_class_desc_type_node = create_pseudo_type_info
1912 ("__si_class_type_info", 0,
1913 build_decl (FIELD_DECL, NULL_TREE, ptr_type_info),
1916 /* Base class internal helper. Pointer to base type, offset to base,
1921 fields[0] = build_decl (FIELD_DECL, NULL_TREE, ptr_type_info);
1922 fields[1] = build_decl (FIELD_DECL, NULL_TREE, integer_types[itk_long]);
1923 base_desc_type_node = make_aggr_type (RECORD_TYPE);
1924 finish_builtin_type (base_desc_type_node, "__base_class_type_info_pseudo",
1925 fields, 1, ptr_type_node);
1926 TYPE_HAS_CONSTRUCTOR (base_desc_type_node) = 1;
1929 /* General heirarchy is created as necessary in this vector. */
1930 vmi_class_desc_type_node = make_tree_vec (10);
1932 /* Pointer type_info. Adds two fields, qualification mask
1933 and pointer to the pointed to type. This is really a descendant of
1934 __pbase_type_info. */
1935 ptr_desc_type_node = create_pseudo_type_info
1936 ("__pointer_type_info", 0,
1937 build_decl (FIELD_DECL, NULL_TREE, integer_type_node),
1938 build_decl (FIELD_DECL, NULL_TREE, ptr_type_info),
1941 /* Pointer to member data type_info. Add qualifications flags,
1942 pointer to the member's type info and pointer to the class.
1943 This is really a descendant of __pbase_type_info. */
1944 ptm_desc_type_node = create_pseudo_type_info
1945 ("__pointer_to_member_type_info", 0,
1946 build_decl (FIELD_DECL, NULL_TREE, integer_type_node),
1947 build_decl (FIELD_DECL, NULL_TREE, ptr_type_info),
1948 build_decl (FIELD_DECL, NULL_TREE, ptr_type_info),
1951 pop_nested_namespace (abi_node);
1954 /* Emit the type_info descriptors which are guaranteed to be in the runtime
1955 support. Generating them here guarantees consistency with the other
1956 structures. We use the following heuristic to determine when the runtime
1957 is being generated. If std::__fundamental_type_info is defined, and it's
1958 destructor is defined, then the runtime is being built. */
1961 emit_support_tinfos ()
1963 static tree *const fundamentals[] =
1968 &char_type_node, &signed_char_type_node, &unsigned_char_type_node,
1969 &short_integer_type_node, &short_unsigned_type_node,
1970 &integer_type_node, &unsigned_type_node,
1971 &long_integer_type_node, &long_unsigned_type_node,
1972 &long_long_integer_type_node, &long_long_unsigned_type_node,
1973 &float_type_node, &double_type_node, &long_double_type_node,
1977 tree bltn_type, dtor;
1979 push_nested_namespace (abi_node);
1980 bltn_type = xref_tag (class_type_node,
1981 get_identifier ("__fundamental_type_info"), 1);
1982 pop_nested_namespace (abi_node);
1983 if (!COMPLETE_TYPE_P (bltn_type))
1985 dtor = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (bltn_type), 1);
1986 if (DECL_EXTERNAL (dtor))
1989 for (ix = 0; fundamentals[ix]; ix++)
1991 tree bltn = *fundamentals[ix];
1992 tree bltn_ptr = build_pointer_type (bltn);
1993 tree bltn_const_ptr = build_pointer_type
1994 (build_qualified_type (bltn, TYPE_QUAL_CONST));
1997 tinfo = get_tinfo_decl (bltn);
1998 TREE_USED (tinfo) = 1;
1999 TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (tinfo)) = 1;
2001 tinfo = get_tinfo_decl (bltn_ptr);
2002 TREE_USED (tinfo) = 1;
2003 TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (tinfo)) = 1;
2005 tinfo = get_tinfo_decl (bltn_const_ptr);
2006 TREE_USED (tinfo) = 1;
2007 TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (tinfo)) = 1;
2011 /* Return non-zero, iff T is a type_info variable which has not had a
2012 definition emitted for it. */
2015 tinfo_decl_p (t, data)
2017 void *data ATTRIBUTE_UNUSED;
2019 return TREE_CODE (t) == VAR_DECL
2020 && IDENTIFIER_GLOBAL_VALUE (DECL_NAME (t)) == (t)
2021 && TREE_TYPE (t) == tinfo_decl_type
2022 && TREE_TYPE (DECL_NAME (t));
2025 /* Emit a suitable type_info definition for the type_info decl pointed to by
2026 DECL_PTR. We emit a completely new variable, of the correct type for the
2027 actual type this is describing. The DECL_ASSEMBLER_NAME of the generated
2028 definition is set to that of the supplied decl, so that they can be tied
2029 up. Mark the supplied decl as having been dealt with. Emitting one
2030 definition might cause other definitions to be required.
2032 We need to do things this way, because we're trying to do something like
2038 extern const A tinfo_var;
2040 const B tinfo_var = {...};
2042 which is not permitted. Also, we've not necessarily seen the definition of B.
2043 So we do something like the following,
2045 extern const A tinfo_var;
2048 const void *vtable_ptr;
2056 const pseudo_B proxy_tinfo_var attribute((assembler_name="tinfo_var")) =
2058 {&B::vtable, "..."},
2062 pseudo_A and pseudo_B must be layout equivalent to the real definitions in
2066 emit_tinfo_decl (decl_ptr, data)
2068 void *data ATTRIBUTE_UNUSED;
2070 tree tinfo_decl = *decl_ptr;
2071 tree tinfo_type, decl;
2073 my_friendly_assert (TREE_TYPE (tinfo_decl) == tinfo_decl_type, 20000121);
2074 tinfo_type = TREE_TYPE (DECL_NAME (tinfo_decl));
2075 my_friendly_assert (tinfo_type != NULL_TREE, 20000120);
2077 if (!DECL_NEEDED_P (tinfo_decl))
2079 /* Say we've dealt with it. */
2080 TREE_TYPE (DECL_NAME (tinfo_decl)) = NULL_TREE;
2082 create_tinfo_types ();
2083 decl = synthesize_tinfo_var (tinfo_type, DECL_ASSEMBLER_NAME (tinfo_decl));