+++ /dev/null
-/* RunTime Type Identification
- Copyright (C) 1995-2022 Free Software Foundation, Inc.
- Mostly written by Jason Merrill (jason@cygnus.com).
-
-This file is part of GCC.
-
-GCC is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 3, or (at your option)
-any later version.
-
-GCC is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING3. If not see
-<http://www.gnu.org/licenses/>. */
-
-#include "config.h"
-#include "system.h"
-#include "coretypes.h"
-#include "target.h"
-#include "cp-tree.h"
-#include "memmodel.h"
-#include "tm_p.h"
-#include "stringpool.h"
-#include "intl.h"
-#include "stor-layout.h"
-#include "c-family/c-pragma.h"
-#include "gcc-rich-location.h"
-
-/* C++ returns type information to the user in struct type_info
- objects. We also use type information to implement dynamic_cast and
- exception handlers. Type information for a particular type is
- indicated with an ABI defined structure derived from type_info.
- This would all be very straight forward, but for the fact that the
- runtime library provides the definitions of the type_info structure
- and the ABI defined derived classes. We cannot build declarations
- of them directly in the compiler, but we need to layout objects of
- their type. Somewhere we have to lie.
-
- We define layout compatible POD-structs with compiler-defined names
- and generate the appropriate initializations for them (complete
- with explicit mention of their vtable). When we have to provide a
- type_info to the user we reinterpret_cast the internal compiler
- type to type_info. A well formed program can only explicitly refer
- to the type_infos of complete types (& cv void). However, we chain
- pointer type_infos to the pointed-to-type, and that can be
- incomplete. We only need the addresses of such incomplete
- type_info objects for static initialization.
-
- The type information VAR_DECL of a type is held on the
- get_global_binding of the type's mangled name. That VAR_DECL
- will be the internal type. It will usually have the correct
- internal type reflecting the kind of type it represents (pointer,
- array, function, class, inherited class, etc). When the type it
- represents is incomplete, it will have the internal type
- corresponding to type_info. That will only happen at the end of
- translation, when we are emitting the type info objects. */
-
-/* Auxiliary data we hold for each type_info derived object we need. */
-struct GTY (()) tinfo_s {
- tree type; /* The (const-qualified) RECORD_TYPE for this type_info object */
-
- tree vtable; /* The VAR_DECL of the vtable. Only filled at end of
- translation. */
-
- tree name; /* IDENTIFIER_NODE for the ABI specified name of
- the type_info derived type. */
-};
-
-
-enum tinfo_kind
-{
- TK_TYPE_INFO_TYPE, /* abi::__type_info_pseudo */
- TK_BASE_TYPE, /* abi::__base_class_type_info */
- TK_DERIVED_TYPES, /* Start of types derived from abi::__type_info */
- TK_BUILTIN_TYPE = TK_DERIVED_TYPES, /* abi::__fundamental_type_info */
- TK_ARRAY_TYPE, /* abi::__array_type_info */
- TK_FUNCTION_TYPE, /* abi::__function_type_info */
- TK_ENUMERAL_TYPE, /* abi::__enum_type_info */
- TK_POINTER_TYPE, /* abi::__pointer_type_info */
- TK_POINTER_MEMBER_TYPE, /* abi::__pointer_to_member_type_info */
- TK_CLASS_TYPE, /* abi::__class_type_info */
- TK_SI_CLASS_TYPE, /* abi::__si_class_type_info */
- TK_VMI_CLASS_TYPES, /* abi::__vmi_class_type_info<int> */
- TK_MAX
-};
-
-/* Names of the tinfo types. Must be same order as TK enumeration
- above. */
-
-static const char *const tinfo_names[TK_MAX] =
-{
- "__type_info",
- "__base_class_type_info",
- "__fundamental_type_info",
- "__array_type_info",
- "__function_type_info",
- "__enum_type_info",
- "__pointer_type_info",
- "__pointer_to_member_type_info",
- "__class_type_info",
- "__si_class_type_info",
- "__vmi_class_type_info"
-};
-
-/* Helper macro to get maximum scalar-width of pointer or of the 'long'-type.
- This of interest for llp64 targets. */
-#define LONGPTR_T \
- integer_types[(POINTER_SIZE <= TYPE_PRECISION (integer_types[itk_long]) \
- ? itk_long : itk_long_long)]
-
-/* A vector of all tinfo decls that haven't yet been emitted. */
-vec<tree, va_gc> *unemitted_tinfo_decls;
-
-/* A vector of all type_info derived types we need. The first few are
- fixed and created early. The remainder are for multiple inheritance
- and are generated as needed. */
-static GTY (()) vec<tinfo_s, va_gc> *tinfo_descs;
-
-static tree tinfo_name (tree, bool);
-static tree build_dynamic_cast_1 (location_t, tree, tree, tsubst_flags_t);
-static tree throw_bad_cast (void);
-static tree throw_bad_typeid (void);
-static bool typeid_ok_p (void);
-static int qualifier_flags (tree);
-static bool target_incomplete_p (tree);
-static tree tinfo_base_init (tinfo_s *, tree);
-static tree generic_initializer (tinfo_s *, tree);
-static tree ptr_initializer (tinfo_s *, tree);
-static tree ptm_initializer (tinfo_s *, tree);
-static tree class_initializer (tinfo_s *, tree, unsigned, ...);
-static tree get_pseudo_ti_init (tree, unsigned);
-static unsigned get_pseudo_ti_index (tree);
-static tinfo_s *get_tinfo_desc (unsigned);
-static void create_tinfo_types (void);
-static bool typeinfo_in_lib_p (tree);
-
-static int doing_runtime = 0;
-\f
-/* Create the internal versions of the ABI types. */
-
-void
-init_rtti_processing (void)
-{
- vec_alloc (unemitted_tinfo_decls, 124);
-
- create_tinfo_types ();
-}
-
-/* Given the expression EXP of type `class *', return the head of the
- object pointed to by EXP with type cv void*, if the class has any
- virtual functions (TYPE_POLYMORPHIC_P), else just return the
- expression. */
-
-tree
-build_headof (tree exp)
-{
- tree type = TREE_TYPE (exp);
- tree offset;
- tree index;
-
- gcc_assert (TYPE_PTR_P (type));
- type = TREE_TYPE (type);
-
- if (!TYPE_POLYMORPHIC_P (type))
- return exp;
-
- /* We use this a couple of times below, protect it. */
- exp = save_expr (exp);
-
- /* The offset-to-top field is at index -2 from the vptr. */
- index = build_int_cst (NULL_TREE,
- -2 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
-
- offset = build_vtbl_ref (cp_build_fold_indirect_ref (exp),
- index);
-
- cp_build_qualified_type (ptr_type_node,
- cp_type_quals (TREE_TYPE (exp)));
- return fold_build_pointer_plus (exp, offset);
-}
-
-/* Get a bad_cast node for the program to throw...
-
- See libstdc++/exception.cc for __throw_bad_cast */
-
-static tree
-throw_bad_cast (void)
-{
- static tree fn;
- if (!fn)
- {
- tree name = get_identifier ("__cxa_bad_cast");
- fn = get_global_binding (name);
- if (!fn)
- fn = push_throw_library_fn
- (name, build_function_type_list (ptr_type_node, NULL_TREE));
- }
-
- return build_cxx_call (fn, 0, NULL, tf_warning_or_error);
-}
-
-/* Return an expression for "__cxa_bad_typeid()". The expression
- returned is an lvalue of type "const std::type_info". */
-
-static tree
-throw_bad_typeid (void)
-{
- static tree fn;
- if (!fn)
- {
- tree name = get_identifier ("__cxa_bad_typeid");
- fn = get_global_binding (name);
- if (!fn)
- {
- tree t = build_reference_type (const_type_info_type_node);
- t = build_function_type_list (t, NULL_TREE);
- fn = push_throw_library_fn (name, t);
- }
- }
-
- return build_cxx_call (fn, 0, NULL, tf_warning_or_error);
-}
-\f
-/* const type_info*. */
-
-inline tree
-type_info_ptr_type ()
-{
- return build_pointer_type (const_type_info_type_node);
-}
-
-/* Return a pointer to a type_info object describing TYPE, suitably
- cast to the language defined type (for typeid) or void (for building
- up the descriptors). */
-
-static tree
-get_tinfo_ptr (tree type, bool voidp = false)
-{
- tree decl = get_tinfo_decl (type);
- mark_used (decl);
-
- tree ptype = voidp ? const_ptr_type_node : type_info_ptr_type ();
- return build_nop (ptype, build_address (decl));
-}
-static inline tree
-get_void_tinfo_ptr (tree type)
-{
- return get_tinfo_ptr (type, true);
-}
-
-/* Return an lvalue expression whose type is "const std::type_info"
- and whose value indicates the type of the expression EXP. If EXP
- is a reference to a polymorphic class, return the dynamic type;
- otherwise return the static type of the expression. */
-
-static tree
-get_tinfo_decl_dynamic (tree exp, tsubst_flags_t complain)
-{
- tree type;
- tree t;
-
- if (error_operand_p (exp))
- return error_mark_node;
-
- exp = resolve_nondeduced_context (exp, complain);
-
- /* Peel back references, so they match. */
- type = non_reference (unlowered_expr_type (exp));
-
- /* Peel off cv qualifiers. */
- type = cv_unqualified (type);
-
- /* For UNKNOWN_TYPEs call complete_type_or_else to get diagnostics. */
- if (CLASS_TYPE_P (type) || type == unknown_type_node
- || type == init_list_type_node)
- type = complete_type_or_maybe_complain (type, exp, complain);
-
- if (!type)
- return error_mark_node;
-
- /* If exp is a reference to polymorphic type, get the real type_info. */
- if (TYPE_POLYMORPHIC_P (type) && ! resolves_to_fixed_type_p (exp, 0))
- {
- /* build reference to type_info from vtable. */
- tree index;
-
- /* The RTTI information is at index -1. */
- index = build_int_cst (NULL_TREE,
- -1 * TARGET_VTABLE_DATA_ENTRY_DISTANCE);
- t = build_vtbl_ref (exp, index);
- t = convert (type_info_ptr_type (), t);
- }
- else
- /* Otherwise return the type_info for the static type of the expr. */
- t = get_tinfo_ptr (type);
-
- return cp_build_fold_indirect_ref (t);
-}
-
-static bool
-typeid_ok_p (void)
-{
- if (! flag_rtti)
- {
- error ("cannot use %<typeid%> with %<-fno-rtti%>");
- return false;
- }
-
- if (!const_type_info_type_node)
- {
- tree name = get_identifier ("type_info");
- tree decl = lookup_qualified_name (std_node, name);
- if (TREE_CODE (decl) != TYPE_DECL)
- {
- gcc_rich_location richloc (input_location);
- maybe_add_include_fixit (&richloc, "<typeinfo>", false);
- error_at (&richloc,
- "must %<#include <typeinfo>%> before using"
- " %<typeid%>");
-
- return false;
- }
- const_type_info_type_node
- = cp_build_qualified_type (TREE_TYPE (decl), TYPE_QUAL_CONST);
- }
-
- tree pseudo = TYPE_MAIN_VARIANT (get_tinfo_desc (TK_TYPE_INFO_TYPE)->type);
- tree real = TYPE_MAIN_VARIANT (const_type_info_type_node);
-
- /* Make sure abi::__type_info_pseudo has the same alias set
- as std::type_info. */
- if (! TYPE_ALIAS_SET_KNOWN_P (pseudo))
- TYPE_ALIAS_SET (pseudo) = get_alias_set (real);
- else
- gcc_assert (TYPE_ALIAS_SET (pseudo) == get_alias_set (real));
-
- return true;
-}
-
-/* Return an expression for "typeid(EXP)". The expression returned is
- an lvalue of type "const std::type_info". */
-
-tree
-build_typeid (tree exp, tsubst_flags_t complain)
-{
- tree cond = NULL_TREE, initial_expr = exp;
- int nonnull = 0;
-
- if (exp == error_mark_node || !typeid_ok_p ())
- return error_mark_node;
-
- if (processing_template_decl)
- return build_min (TYPEID_EXPR, const_type_info_type_node, exp);
-
- if (TYPE_POLYMORPHIC_P (TREE_TYPE (exp))
- && ! resolves_to_fixed_type_p (exp, &nonnull)
- && ! nonnull)
- {
- /* So we need to look into the vtable of the type of exp.
- Make sure it isn't a null lvalue. */
- exp = cp_build_addr_expr (exp, complain);
- exp = save_expr (exp);
- cond = cp_convert (boolean_type_node, exp, complain);
- exp = cp_build_fold_indirect_ref (exp);
- }
-
- exp = get_tinfo_decl_dynamic (exp, complain);
-
- if (exp == error_mark_node)
- return error_mark_node;
-
- if (cond)
- {
- tree bad = throw_bad_typeid ();
-
- exp = build3 (COND_EXPR, TREE_TYPE (exp), cond, exp, bad);
- }
- else
- mark_type_use (initial_expr);
-
- return exp;
-}
-
-/* Generate the NTBS name of a type. If MARK_PRIVATE, put a '*' in front so that
- comparisons will be done by pointer rather than string comparison. */
-static tree
-tinfo_name (tree type, bool mark_private)
-{
- const char *name;
- int length;
- tree name_string;
-
- name = mangle_type_string (type);
- length = strlen (name);
-
- if (mark_private)
- {
- /* Inject '*' at beginning of name to force pointer comparison. */
- char* buf = (char*) XALLOCAVEC (char, length + 2);
- buf[0] = '*';
- memcpy (buf + 1, name, length + 1);
- name_string = build_string (length + 2, buf);
- }
- else
- name_string = build_string (length + 1, name);
-
- return fix_string_type (name_string);
-}
-
-/* Return a VAR_DECL for the internal ABI defined type_info object for
- TYPE. You must arrange that the decl is mark_used, if actually use
- it --- decls in vtables are only used if the vtable is output. */
-
-tree
-get_tinfo_decl (tree type)
-{
- if (variably_modified_type_p (type, /*fn=*/NULL_TREE))
- {
- error ("cannot create type information for type %qT because "
- "it involves types of variable size",
- type);
- return error_mark_node;
- }
-
- if (TREE_CODE (type) == METHOD_TYPE)
- type = build_function_type (TREE_TYPE (type),
- TREE_CHAIN (TYPE_ARG_TYPES (type)));
-
- return get_tinfo_decl_direct (type, NULL, -1);
-}
-
-/* Get or create a tinfo VAR_DECL directly from the provided information.
- The caller must have already checked it is valid to do so. */
-
-tree
-get_tinfo_decl_direct (tree type, tree name, int pseudo_ix)
-{
- /* For a class type, the variable is cached in the type node
- itself. */
- tree d = NULL_TREE;
-
- gcc_checking_assert (TREE_CODE (type) != METHOD_TYPE);
-
- if (pseudo_ix < 0)
- type = complete_type (type);
-
- if (CLASS_TYPE_P (type))
- d = CLASSTYPE_TYPEINFO_VAR (TYPE_MAIN_VARIANT (type));
-
- if (!name)
- name = mangle_typeinfo_for_type (type);
-
- if (!CLASS_TYPE_P (type) || TYPE_TRANSPARENT_AGGR (type))
- d = get_global_binding (name);
-
- if (!d)
- {
- /* Create it. */
- if (pseudo_ix < 0)
- pseudo_ix = get_pseudo_ti_index (type);
-
- const tinfo_s *ti = get_tinfo_desc (pseudo_ix);
-
- d = build_lang_decl (VAR_DECL, name, ti->type);
- SET_DECL_ASSEMBLER_NAME (d, name);
- /* Remember the type it is for. */
- TREE_TYPE (name) = type;
- DECL_TINFO_P (d) = 1;
- DECL_ARTIFICIAL (d) = 1;
- DECL_IGNORED_P (d) = 1;
- TREE_READONLY (d) = 1;
- TREE_STATIC (d) = 1;
- /* Tell equal_address_to that different tinfo decls never
- overlap. */
- if (vec_safe_is_empty (unemitted_tinfo_decls))
- DECL_ATTRIBUTES (d)
- = build_tree_list (get_identifier ("non overlapping"),
- NULL_TREE);
- else
- DECL_ATTRIBUTES (d)
- = DECL_ATTRIBUTES ((*unemitted_tinfo_decls)[0]);
-
- /* Mark the variable as undefined -- but remember that we can
- define it later if we need to do so. */
- DECL_EXTERNAL (d) = 1;
- DECL_NOT_REALLY_EXTERN (d) = 1;
- set_linkage_according_to_type (type, d);
-
- d = pushdecl_top_level_and_finish (d, NULL_TREE);
- if (CLASS_TYPE_P (type))
- CLASSTYPE_TYPEINFO_VAR (TYPE_MAIN_VARIANT (type)) = d;
-
- /* Add decl to the global array of tinfo decls. */
- vec_safe_push (unemitted_tinfo_decls, d);
- }
-
- return d;
-}
-
-/* Return the type_info object for TYPE. */
-
-tree
-get_typeid (tree type, tsubst_flags_t complain)
-{
- if (type == error_mark_node || !typeid_ok_p ())
- return error_mark_node;
-
- if (processing_template_decl)
- return build_min (TYPEID_EXPR, const_type_info_type_node, type);
-
- /* If the type of the type-id is a reference type, the result of the
- typeid expression refers to a type_info object representing the
- referenced type. */
- type = non_reference (type);
-
- /* This is not one of the uses of a qualified function type in 8.3.5. */
- if (TREE_CODE (type) == FUNCTION_TYPE
- && (type_memfn_quals (type) != TYPE_UNQUALIFIED
- || type_memfn_rqual (type) != REF_QUAL_NONE))
- {
- if (complain & tf_error)
- error ("%<typeid%> of qualified function type %qT", type);
- return error_mark_node;
- }
-
- /* The top-level cv-qualifiers of the lvalue expression or the type-id
- that is the operand of typeid are always ignored. */
- type = cv_unqualified (type);
-
- /* For UNKNOWN_TYPEs call complete_type_or_else to get diagnostics. */
- if (CLASS_TYPE_P (type) || type == unknown_type_node
- || type == init_list_type_node)
- type = complete_type_or_maybe_complain (type, NULL_TREE, complain);
-
- if (!type)
- return error_mark_node;
-
- return cp_build_fold_indirect_ref (get_tinfo_ptr (type));
-}
-
-/* Check whether TEST is null before returning RESULT. If TEST is used in
- RESULT, it must have previously had a save_expr applied to it. */
-
-tree
-build_if_nonnull (tree test, tree result, tsubst_flags_t complain)
-{
- tree null_ptr = cp_convert (TREE_TYPE (test), nullptr_node, complain);
- tree cond = build2 (NE_EXPR, boolean_type_node, test, null_ptr);
-
- /* This is a compiler generated comparison, don't emit
- e.g. -Wnonnull-compare warning for it. */
- suppress_warning (cond, OPT_Wnonnull);
-
- null_ptr = cp_convert (TREE_TYPE (result), nullptr_node, complain);
- cond = build3 (COND_EXPR, TREE_TYPE (result), cond, result, null_ptr);
-
- /* Likewise, don't emit -Wnonnull for using the result to call
- a member function. */
- suppress_warning (cond, OPT_Wnonnull);
- return cond;
-}
-
-/* Execute a dynamic cast, as described in section 5.2.6 of the 9/93 working
- paper. */
-
-static tree
-build_dynamic_cast_1 (location_t loc, tree type, tree expr,
- tsubst_flags_t complain)
-{
- enum tree_code tc = TREE_CODE (type);
- tree exprtype;
- tree dcast_fn;
- tree old_expr = expr;
- const char *errstr = NULL;
-
- /* Save casted types in the function's used types hash table. */
- used_types_insert (type);
-
- /* T shall be a pointer or reference to a complete class type, or
- `pointer to cv void''. */
- switch (tc)
- {
- case POINTER_TYPE:
- if (VOID_TYPE_P (TREE_TYPE (type)))
- break;
- /* Fall through. */
- case REFERENCE_TYPE:
- if (! MAYBE_CLASS_TYPE_P (TREE_TYPE (type)))
- {
- errstr = _("target is not pointer or reference to class");
- goto fail;
- }
- if (!COMPLETE_TYPE_P (complete_type (TREE_TYPE (type))))
- {
- errstr = _("target is not pointer or reference to complete type");
- goto fail;
- }
- break;
-
- default:
- errstr = _("target is not pointer or reference");
- goto fail;
- }
-
- if (tc == POINTER_TYPE)
- {
- expr = decay_conversion (expr, complain);
- exprtype = TREE_TYPE (expr);
-
- /* If T is a pointer type, v shall be an rvalue of a pointer to
- complete class type, and the result is an rvalue of type T. */
-
- expr = mark_rvalue_use (expr);
-
- if (!TYPE_PTR_P (exprtype))
- {
- errstr = _("source is not a pointer");
- goto fail;
- }
- if (! MAYBE_CLASS_TYPE_P (TREE_TYPE (exprtype)))
- {
- errstr = _("source is not a pointer to class");
- goto fail;
- }
- if (!COMPLETE_TYPE_P (complete_type (TREE_TYPE (exprtype))))
- {
- errstr = _("source is a pointer to incomplete type");
- goto fail;
- }
- }
- else
- {
- expr = mark_lvalue_use (expr);
- exprtype = TREE_TYPE (expr);
-
- /* T is a reference type, v shall be an lvalue of a complete class
- type, and the result is an lvalue of the type referred to by T. */
- if (! MAYBE_CLASS_TYPE_P (exprtype))
- {
- errstr = _("source is not of class type");
- goto fail;
- }
- if (!COMPLETE_TYPE_P (complete_type (exprtype)))
- {
- errstr = _("source is of incomplete class type");
- goto fail;
- }
-
- exprtype = cp_build_reference_type (exprtype, !lvalue_p (expr));
- }
-
- /* The dynamic_cast operator shall not cast away constness. */
- if (!at_least_as_qualified_p (TREE_TYPE (type),
- TREE_TYPE (exprtype)))
- {
- errstr = _("conversion casts away constness");
- goto fail;
- }
-
- /* If *type is an unambiguous accessible base class of *exprtype,
- convert statically. */
- {
- tree binfo = lookup_base (TREE_TYPE (exprtype), TREE_TYPE (type),
- ba_check, NULL, complain);
- if (binfo)
- return build_static_cast (loc, type, expr, complain);
- }
-
- /* Apply trivial conversion T -> T& for dereferenced ptrs. */
- if (tc == REFERENCE_TYPE)
- expr = convert_to_reference (exprtype, expr, CONV_IMPLICIT,
- LOOKUP_NORMAL, NULL_TREE, complain);
-
- /* Otherwise *exprtype must be a polymorphic class (have a vtbl). */
- if (TYPE_POLYMORPHIC_P (TREE_TYPE (exprtype)))
- {
- tree expr1;
- /* if TYPE is `void *', return pointer to complete object. */
- if (tc == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (type)))
- {
- /* if b is an object, dynamic_cast<void *>(&b) == (void *)&b. */
- if (TREE_CODE (expr) == ADDR_EXPR
- && VAR_P (TREE_OPERAND (expr, 0))
- && TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == RECORD_TYPE)
- return build1 (NOP_EXPR, type, expr);
-
- /* Since expr is used twice below, save it. */
- expr = save_expr (expr);
-
- expr1 = build_headof (expr);
- if (TREE_TYPE (expr1) != type)
- expr1 = build1 (NOP_EXPR, type, expr1);
- return build_if_nonnull (expr, expr1, complain);
- }
- else
- {
- tree retval;
- tree result, td2, td3;
- tree elems[4];
- tree static_type, target_type, boff;
-
- /* If we got here, we can't convert statically. Therefore,
- dynamic_cast<D&>(b) (b an object) cannot succeed. */
- if (tc == REFERENCE_TYPE)
- {
- if (VAR_P (old_expr)
- && TREE_CODE (TREE_TYPE (old_expr)) == RECORD_TYPE)
- {
- tree expr = throw_bad_cast ();
- if (complain & tf_warning)
- warning_at (loc, 0,
- "%<dynamic_cast<%#T>(%#D)%> can never succeed",
- type, old_expr);
- /* Bash it to the expected type. */
- TREE_TYPE (expr) = type;
- return expr;
- }
- }
- /* Ditto for dynamic_cast<D*>(&b). */
- else if (TREE_CODE (expr) == ADDR_EXPR)
- {
- tree op = TREE_OPERAND (expr, 0);
- if (VAR_P (op)
- && TREE_CODE (TREE_TYPE (op)) == RECORD_TYPE)
- {
- if (complain & tf_warning)
- warning_at (loc, 0,
- "%<dynamic_cast<%#T>(%#D)%> can never succeed",
- type, op);
- retval = build_int_cst (type, 0);
- return retval;
- }
- }
-
- /* Use of dynamic_cast when -fno-rtti is prohibited. */
- if (!flag_rtti)
- {
- if (complain & tf_error)
- error_at (loc,
- "%<dynamic_cast%> not permitted with %<-fno-rtti%>");
- return error_mark_node;
- }
-
- target_type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
- static_type = TYPE_MAIN_VARIANT (TREE_TYPE (exprtype));
- td2 = get_tinfo_decl (target_type);
- if (!mark_used (td2, complain) && !(complain & tf_error))
- return error_mark_node;
- td2 = cp_build_addr_expr (td2, complain);
- td3 = get_tinfo_decl (static_type);
- if (!mark_used (td3, complain) && !(complain & tf_error))
- return error_mark_node;
- td3 = cp_build_addr_expr (td3, complain);
-
- /* Determine how T and V are related. */
- boff = dcast_base_hint (static_type, target_type);
-
- /* Since expr is used twice below, save it. */
- expr = save_expr (expr);
-
- expr1 = expr;
- if (tc == REFERENCE_TYPE)
- expr1 = cp_build_addr_expr (expr1, complain);
-
- elems[0] = expr1;
- elems[1] = td3;
- elems[2] = td2;
- elems[3] = boff;
-
- dcast_fn = dynamic_cast_node;
- if (!dcast_fn)
- {
- unsigned flags = push_abi_namespace ();
- tree tinfo_ptr = xref_tag (class_type,
- get_identifier ("__class_type_info"));
- tinfo_ptr = cp_build_qualified_type (tinfo_ptr, TYPE_QUAL_CONST);
- tinfo_ptr = build_pointer_type (tinfo_ptr);
-
- const char *fn_name = "__dynamic_cast";
- /* void *() (void const *, __class_type_info const *,
- __class_type_info const *, ptrdiff_t) */
- tree fn_type = (build_function_type_list
- (ptr_type_node, const_ptr_type_node,
- tinfo_ptr, tinfo_ptr, ptrdiff_type_node,
- NULL_TREE));
- dcast_fn = (build_library_fn_ptr
- (fn_name, fn_type, ECF_LEAF | ECF_PURE | ECF_NOTHROW));
- pop_abi_namespace (flags);
- dynamic_cast_node = dcast_fn;
- }
- result = build_cxx_call (dcast_fn, 4, elems, complain);
- SET_EXPR_LOCATION (result, loc);
-
- if (tc == REFERENCE_TYPE)
- {
- tree bad = throw_bad_cast ();
- tree neq;
-
- result = save_expr (result);
- neq = cp_truthvalue_conversion (result, complain);
- return cp_convert (type,
- build3 (COND_EXPR, TREE_TYPE (result),
- neq, result, bad), complain);
- }
-
- /* Now back to the type we want from a void*. */
- result = cp_convert (type, result, complain);
- return build_if_nonnull (expr, result, complain);
- }
- }
- else
- errstr = _("source type is not polymorphic");
-
- fail:
- if (complain & tf_error)
- error_at (loc, "cannot %<dynamic_cast%> %qE (of type %q#T) "
- "to type %q#T (%s)",
- old_expr, TREE_TYPE (old_expr), type, errstr);
- return error_mark_node;
-}
-
-tree
-build_dynamic_cast (location_t loc, tree type, tree expr,
- tsubst_flags_t complain)
-{
- tree r;
-
- if (type == error_mark_node || expr == error_mark_node)
- return error_mark_node;
-
- if (processing_template_decl)
- {
- expr = build_min (DYNAMIC_CAST_EXPR, type, expr);
- TREE_SIDE_EFFECTS (expr) = 1;
- r = convert_from_reference (expr);
- protected_set_expr_location (r, loc);
- return r;
- }
-
- r = convert_from_reference (build_dynamic_cast_1 (loc, type, expr,
- complain));
- if (r != error_mark_node)
- maybe_warn_about_useless_cast (loc, type, expr, complain);
- protected_set_expr_location (r, loc);
- return r;
-}
-
-/* Return the runtime bit mask encoding the qualifiers of TYPE. */
-
-static int
-qualifier_flags (tree type)
-{
- int flags = 0;
- int quals = cp_type_quals (type);
-
- if (quals & TYPE_QUAL_CONST)
- flags |= 1;
- if (quals & TYPE_QUAL_VOLATILE)
- flags |= 2;
- if (quals & TYPE_QUAL_RESTRICT)
- flags |= 4;
- return flags;
-}
-
-/* Return true, if the pointer chain TYPE ends at an incomplete type, or
- contains a pointer to member of an incomplete class. */
-
-static bool
-target_incomplete_p (tree type)
-{
- while (true)
- if (TYPE_PTRDATAMEM_P (type))
- {
- if (!COMPLETE_TYPE_P (TYPE_PTRMEM_CLASS_TYPE (type)))
- return true;
- type = TYPE_PTRMEM_POINTED_TO_TYPE (type);
- }
- else if (TYPE_PTR_P (type))
- type = TREE_TYPE (type);
- else
- return !COMPLETE_OR_VOID_TYPE_P (type);
-}
-
-/* Returns true if TYPE involves an incomplete class type; in that
- case, typeinfo variables for TYPE should be emitted with internal
- linkage. */
-
-static bool
-involves_incomplete_p (tree type)
-{
- switch (TREE_CODE (type))
- {
- case POINTER_TYPE:
- return target_incomplete_p (TREE_TYPE (type));
-
- case OFFSET_TYPE:
- ptrmem:
- return
- (target_incomplete_p (TYPE_PTRMEM_POINTED_TO_TYPE (type))
- || !COMPLETE_TYPE_P (TYPE_PTRMEM_CLASS_TYPE (type)));
-
- case RECORD_TYPE:
- if (TYPE_PTRMEMFUNC_P (type))
- goto ptrmem;
- /* Fall through. */
- case UNION_TYPE:
- if (!COMPLETE_TYPE_P (type))
- return true;
- /* Fall through. */
- default:
- /* All other types do not involve incomplete class types. */
- return false;
- }
-}
-
-/* Return a CONSTRUCTOR for the common part of the type_info objects. This
- is the vtable pointer and NTBS name. The NTBS name is emitted as a
- comdat const char array, so it becomes a unique key for the type. Generate
- and emit that VAR_DECL here. (We can't always emit the type_info itself
- as comdat, because of pointers to incomplete.) */
-
-static tree
-tinfo_base_init (tinfo_s *ti, tree target)
-{
- tree init;
- tree name_decl;
- tree vtable_ptr;
- vec<constructor_elt, va_gc> *v;
-
- {
- tree name_name, name_string;
-
- /* Generate the NTBS array variable. */
- tree name_type = build_cplus_array_type
- (cp_build_qualified_type (char_type_node, TYPE_QUAL_CONST),
- NULL_TREE);
-
- /* Determine the name of the variable -- and remember with which
- type it is associated. */
- name_name = mangle_typeinfo_string_for_type (target);
- TREE_TYPE (name_name) = target;
-
- name_decl = build_lang_decl (VAR_DECL, name_name, name_type);
- SET_DECL_ASSEMBLER_NAME (name_decl, name_name);
- DECL_ARTIFICIAL (name_decl) = 1;
- DECL_IGNORED_P (name_decl) = 1;
- TREE_READONLY (name_decl) = 1;
- TREE_STATIC (name_decl) = 1;
- DECL_EXTERNAL (name_decl) = 0;
- DECL_TINFO_P (name_decl) = 1;
- set_linkage_according_to_type (target, name_decl);
- import_export_decl (name_decl);
- name_string = tinfo_name (target, !TREE_PUBLIC (name_decl));
- DECL_INITIAL (name_decl) = name_string;
- mark_used (name_decl);
- pushdecl_top_level_and_finish (name_decl, name_string);
- }
-
- vtable_ptr = ti->vtable;
- if (!vtable_ptr)
- {
- int flags = push_abi_namespace ();
- tree real_type = xref_tag (class_type, ti->name);
- tree real_decl = TYPE_NAME (real_type);
- DECL_SOURCE_LOCATION (real_decl) = BUILTINS_LOCATION;
- pop_abi_namespace (flags);
-
- if (!COMPLETE_TYPE_P (real_type))
- {
- /* We never saw a definition of this type, so we need to
- tell the compiler that this is an exported class, as
- indeed all of the __*_type_info classes are. */
- SET_CLASSTYPE_INTERFACE_KNOWN (real_type);
- CLASSTYPE_INTERFACE_ONLY (real_type) = 1;
- }
-
- vtable_ptr = get_vtable_decl (real_type, /*complete=*/1);
- vtable_ptr = cp_build_addr_expr (vtable_ptr, tf_warning_or_error);
-
- /* We need to point into the middle of the vtable. */
- vtable_ptr = fold_build_pointer_plus
- (vtable_ptr,
- size_binop (MULT_EXPR,
- size_int (2 * TARGET_VTABLE_DATA_ENTRY_DISTANCE),
- TYPE_SIZE_UNIT (vtable_entry_type)));
-
- ti->vtable = vtable_ptr;
- }
-
- vec_alloc (v, 2);
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, vtable_ptr);
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE,
- decay_conversion (name_decl, tf_warning_or_error));
-
- init = build_constructor (init_list_type_node, v);
- TREE_CONSTANT (init) = 1;
- TREE_STATIC (init) = 1;
-
- return init;
-}
-
-/* Return the CONSTRUCTOR expr for a type_info of TYPE. TI provides the
- information about the particular type_info derivation, which adds no
- additional fields to the type_info base. */
-
-static tree
-generic_initializer (tinfo_s *ti, tree target)
-{
- tree init = tinfo_base_init (ti, target);
-
- init = build_constructor_single (init_list_type_node, NULL_TREE, init);
- TREE_CONSTANT (init) = 1;
- TREE_STATIC (init) = 1;
- return init;
-}
-
-/* Return the CONSTRUCTOR expr for a type_info of pointer TYPE.
- TI provides information about the particular type_info derivation,
- which adds target type and qualifier flags members to the type_info base. */
-
-static tree
-ptr_initializer (tinfo_s *ti, tree target)
-{
- tree init = tinfo_base_init (ti, target);
- tree to = TREE_TYPE (target);
- int flags = qualifier_flags (to);
- bool incomplete = target_incomplete_p (to);
- vec<constructor_elt, va_gc> *v;
- vec_alloc (v, 3);
-
- if (incomplete)
- flags |= 8;
- if (tx_safe_fn_type_p (to))
- {
- flags |= 0x20;
- to = tx_unsafe_fn_variant (to);
- }
- if (flag_noexcept_type
- && FUNC_OR_METHOD_TYPE_P (to)
- && TYPE_NOTHROW_P (to))
- {
- flags |= 0x40;
- to = build_exception_variant (to, NULL_TREE);
- }
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, init);
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, build_int_cst (NULL_TREE, flags));
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE,
- get_void_tinfo_ptr (TYPE_MAIN_VARIANT (to)));
-
- init = build_constructor (init_list_type_node, v);
- TREE_CONSTANT (init) = 1;
- TREE_STATIC (init) = 1;
- return init;
-}
-
-/* Return the CONSTRUCTOR expr for a type_info of pointer to member data TYPE.
- TI provides information about the particular type_info derivation,
- which adds class, target type and qualifier flags members to the type_info
- base. */
-
-static tree
-ptm_initializer (tinfo_s *ti, tree target)
-{
- tree init = tinfo_base_init (ti, target);
- tree to = TYPE_PTRMEM_POINTED_TO_TYPE (target);
- tree klass = TYPE_PTRMEM_CLASS_TYPE (target);
- int flags = qualifier_flags (to);
- bool incomplete = target_incomplete_p (to);
- vec<constructor_elt, va_gc> *v;
- vec_alloc (v, 4);
-
- if (incomplete)
- flags |= 0x8;
- if (!COMPLETE_TYPE_P (klass))
- flags |= 0x10;
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, init);
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, build_int_cst (NULL_TREE, flags));
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE,
- get_void_tinfo_ptr (TYPE_MAIN_VARIANT (to)));
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, get_void_tinfo_ptr (klass));
-
- init = build_constructor (init_list_type_node, v);
- TREE_CONSTANT (init) = 1;
- TREE_STATIC (init) = 1;
- return init;
-}
-
-/* Return the CONSTRUCTOR expr for a type_info of class TYPE.
- TI provides information about the particular __class_type_info derivation,
- which adds hint flags and N extra initializers to the type_info base. */
-
-static tree
-class_initializer (tinfo_s *ti, tree target, unsigned n, ...)
-{
- tree init = tinfo_base_init (ti, target);
- va_list extra_inits;
- unsigned i;
- vec<constructor_elt, va_gc> *v;
- vec_alloc (v, n+1);
-
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, init);
- va_start (extra_inits, n);
- for (i = 0; i < n; i++)
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, va_arg (extra_inits, tree));
- va_end (extra_inits);
-
- init = build_constructor (init_list_type_node, v);
- TREE_CONSTANT (init) = 1;
- TREE_STATIC (init) = 1;
- return init;
-}
-
-/* Returns true if the typeinfo for type should be placed in
- the runtime library. */
-
-static bool
-typeinfo_in_lib_p (tree type)
-{
- /* The typeinfo objects for `T*' and `const T*' are in the runtime
- library for simple types T. */
- if (TYPE_PTR_P (type)
- && (cp_type_quals (TREE_TYPE (type)) == TYPE_QUAL_CONST
- || cp_type_quals (TREE_TYPE (type)) == TYPE_UNQUALIFIED))
- type = TREE_TYPE (type);
-
- switch (TREE_CODE (type))
- {
- case INTEGER_TYPE:
- case BOOLEAN_TYPE:
- case REAL_TYPE:
- case VOID_TYPE:
- case NULLPTR_TYPE:
- return true;
-
- case LANG_TYPE:
- /* fall through. */
-
- default:
- return false;
- }
-}
-
-/* Generate the initializer for the type info describing TYPE. TK_INDEX is
- the index of the descriptor in the tinfo_desc vector. */
-
-static tree
-get_pseudo_ti_init (tree type, unsigned tk_index)
-{
- tinfo_s *ti = get_tinfo_desc (tk_index);
-
- gcc_assert (at_eof);
- switch (tk_index)
- {
- case TK_POINTER_MEMBER_TYPE:
- return ptm_initializer (ti, type);
-
- case TK_POINTER_TYPE:
- return ptr_initializer (ti, type);
-
- case TK_BUILTIN_TYPE:
- case TK_ENUMERAL_TYPE:
- case TK_FUNCTION_TYPE:
- case TK_ARRAY_TYPE:
- return generic_initializer (ti, type);
-
- case TK_CLASS_TYPE:
- return class_initializer (ti, type, 0);
-
- case TK_SI_CLASS_TYPE:
- {
- tree base_binfo = BINFO_BASE_BINFO (TYPE_BINFO (type), 0);
- tree tinfo = get_void_tinfo_ptr (BINFO_TYPE (base_binfo));
-
- /* get_tinfo_ptr might have reallocated the tinfo_descs vector. */
- ti = &(*tinfo_descs)[tk_index];
- return class_initializer (ti, type, 1, tinfo);
- }
-
- default:
- {
- int hint = ((CLASSTYPE_REPEATED_BASE_P (type) << 0)
- | (CLASSTYPE_DIAMOND_SHAPED_P (type) << 1));
- tree binfo = TYPE_BINFO (type);
- unsigned nbases = BINFO_N_BASE_BINFOS (binfo);
- vec<tree, va_gc> *base_accesses = BINFO_BASE_ACCESSES (binfo);
- tree offset_type = LONGPTR_T;
- vec<constructor_elt, va_gc> *init_vec = NULL;
-
- gcc_assert (tk_index - TK_VMI_CLASS_TYPES + 1 == nbases);
-
- vec_safe_grow (init_vec, nbases, true);
- /* Generate the base information initializer. */
- for (unsigned ix = nbases; ix--;)
- {
- tree base_binfo = BINFO_BASE_BINFO (binfo, ix);
- int flags = 0;
- tree tinfo;
- tree offset;
- vec<constructor_elt, va_gc> *v;
-
- if ((*base_accesses)[ix] == access_public_node)
- flags |= 2;
- tinfo = get_void_tinfo_ptr (BINFO_TYPE (base_binfo));
- if (BINFO_VIRTUAL_P (base_binfo))
- {
- /* We store the vtable offset at which the virtual
- base offset can be found. */
- offset = BINFO_VPTR_FIELD (base_binfo);
- flags |= 1;
- }
- else
- offset = BINFO_OFFSET (base_binfo);
-
- /* Combine offset and flags into one field. */
- offset = fold_convert (offset_type, offset);
- offset = fold_build2_loc (input_location,
- LSHIFT_EXPR, offset_type, offset,
- build_int_cst (offset_type, 8));
- offset = fold_build2_loc (input_location,
- BIT_IOR_EXPR, offset_type, offset,
- build_int_cst (offset_type, flags));
- vec_alloc (v, 2);
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, tinfo);
- CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, offset);
- tree base_init = build_constructor (init_list_type_node, v);
- constructor_elt *e = &(*init_vec)[ix];
- e->index = NULL_TREE;
- e->value = base_init;
- }
- tree base_inits = build_constructor (init_list_type_node, init_vec);
-
- /* get_tinfo_ptr might have reallocated the tinfo_descs vector. */
- ti = &(*tinfo_descs)[tk_index];
- return class_initializer (ti, type, 3,
- build_int_cst (NULL_TREE, hint),
- build_int_cst (NULL_TREE, nbases),
- base_inits);
- }
- }
-}
-
-/* Return the index of a pseudo type info type node used to describe
- TYPE. TYPE must be a complete type (or cv void), except at the end
- of the translation unit. */
-
-static unsigned
-get_pseudo_ti_index (tree type)
-{
- unsigned ix;
-
- switch (TREE_CODE (type))
- {
- case OFFSET_TYPE:
- ix = TK_POINTER_MEMBER_TYPE;
- break;
-
- case POINTER_TYPE:
- ix = TK_POINTER_TYPE;
- break;
-
- case ENUMERAL_TYPE:
- ix = TK_ENUMERAL_TYPE;
- break;
-
- case FUNCTION_TYPE:
- ix = TK_FUNCTION_TYPE;
- break;
-
- case ARRAY_TYPE:
- ix = TK_ARRAY_TYPE;
- break;
-
- case UNION_TYPE:
- case RECORD_TYPE:
- if (TYPE_PTRMEMFUNC_P (type))
- ix = TK_POINTER_MEMBER_TYPE;
- else if (!COMPLETE_TYPE_P (type))
- {
- if (!at_eof)
- cxx_incomplete_type_error (NULL_TREE, type);
- ix = TK_CLASS_TYPE;
- }
- else if (!TYPE_BINFO (type)
- || !BINFO_N_BASE_BINFOS (TYPE_BINFO (type)))
- ix = TK_CLASS_TYPE;
- else
- {
- tree binfo = TYPE_BINFO (type);
- vec<tree, va_gc> *base_accesses = BINFO_BASE_ACCESSES (binfo);
- tree base_binfo = BINFO_BASE_BINFO (binfo, 0);
- int num_bases = BINFO_N_BASE_BINFOS (binfo);
-
- if (num_bases == 1
- && (*base_accesses)[0] == access_public_node
- && !BINFO_VIRTUAL_P (base_binfo)
- && integer_zerop (BINFO_OFFSET (base_binfo)))
- /* single non-virtual public. */
- ix = TK_SI_CLASS_TYPE;
- else
- ix = TK_VMI_CLASS_TYPES + num_bases - 1;
- }
- break;
-
- default:
- ix = TK_BUILTIN_TYPE;
- break;
- }
- return ix;
-}
-
-/* Return pointer to tinfo descriptor. Possibly creating the tinfo
- descriptor in the first place. */
-
-static tinfo_s *
-get_tinfo_desc (unsigned ix)
-{
- unsigned len = tinfo_descs->length ();
-
- if (len <= ix)
- {
- /* too short, extend. */
- len = ix + 1 - len;
- vec_safe_reserve (tinfo_descs, len);
- tinfo_s elt;
- elt.type = elt.vtable = elt.name = NULL_TREE;
- while (len--)
- tinfo_descs->quick_push (elt);
- }
-
- tinfo_s *res = &(*tinfo_descs)[ix];
-
- if (res->type)
- return res;
-
- /* Ok, we have to create it. This layout must be consistent with
- that defined in the runtime support. We explicitly manage the
- vtable member, and name it for real type as used in the runtime.
- The RECORD type has a different name, to avoid collisions. We
- have to delay generating the VAR_DECL of the vtable until the end
- of the translation, when we'll have seen the library definition,
- if there was one. */
-
- /* Fields to add, chained in reverse order. */
- tree fields = NULL_TREE;
-
- if (ix >= TK_DERIVED_TYPES)
- {
- /* First field is the pseudo type_info base class. */
- tree fld_base = build_decl (BUILTINS_LOCATION, FIELD_DECL, NULL_TREE,
- get_tinfo_desc (TK_TYPE_INFO_TYPE)->type);
-
- DECL_CHAIN (fld_base) = fields;
- fields = fld_base;
- }
-
- switch (ix)
- {
- case TK_TYPE_INFO_TYPE:
- {
- tree fld_ptr = build_decl (BUILTINS_LOCATION, FIELD_DECL,
- NULL_TREE, const_ptr_type_node);
- fields = fld_ptr;
-
- tree fld_str = build_decl (BUILTINS_LOCATION, FIELD_DECL,
- NULL_TREE, const_string_type_node);
- DECL_CHAIN (fld_str) = fields;
- fields = fld_str;
- break;
- }
-
- case TK_BASE_TYPE:
- {
- /* Base class internal helper. Pointer to base type, offset to
- base, flags. */
- tree fld_ptr = build_decl (BUILTINS_LOCATION, FIELD_DECL,
- NULL_TREE, const_ptr_type_node);
- DECL_CHAIN (fld_ptr) = fields;
- fields = fld_ptr;
-
- tree fld_flag = build_decl (BUILTINS_LOCATION, FIELD_DECL,
- NULL_TREE, LONGPTR_T);
- DECL_CHAIN (fld_flag) = fields;
- fields = fld_flag;
- break;
- }
-
- case TK_BUILTIN_TYPE:
- /* Fundamental type_info */
- break;
-
- case TK_ARRAY_TYPE:
- break;
-
- case TK_FUNCTION_TYPE:
- break;
-
- case TK_ENUMERAL_TYPE:
- break;
-
- case TK_POINTER_TYPE:
- case TK_POINTER_MEMBER_TYPE:
- {
- /* Pointer type_info. Adds two fields, qualification mask and
- pointer to the pointed to type. This is really a
- descendant of __pbase_type_info. */
- tree fld_mask = build_decl (BUILTINS_LOCATION, FIELD_DECL,
- NULL_TREE, integer_type_node);
- DECL_CHAIN (fld_mask) = fields;
- fields = fld_mask;
-
- tree fld_ptr = build_decl (BUILTINS_LOCATION, FIELD_DECL,
- NULL_TREE, const_ptr_type_node);
- DECL_CHAIN (fld_ptr) = fields;
- fields = fld_ptr;
-
- if (ix == TK_POINTER_MEMBER_TYPE)
- {
- /* Add a pointer to the class too. */
- tree fld_cls = build_decl (BUILTINS_LOCATION, FIELD_DECL,
- NULL_TREE, const_ptr_type_node);
- DECL_CHAIN (fld_cls) = fields;
- fields = fld_cls;
- }
- break;
- }
-
- case TK_CLASS_TYPE:
- /* Class type_info. No additional fields. */
- break;
-
- case TK_SI_CLASS_TYPE:
- {
- /* Single public non-virtual base class. Add pointer to base
- class. This is really a descendant of
- __class_type_info. */
- tree fld_ptr = build_decl (BUILTINS_LOCATION, FIELD_DECL,
- NULL_TREE, const_ptr_type_node);
- DECL_CHAIN (fld_ptr) = fields;
- fields = fld_ptr;
- break;
- }
-
- default: /* Multiple inheritance. */
- {
- unsigned num_bases = ix - TK_VMI_CLASS_TYPES + 1;
-
- tree fld_flg = build_decl (BUILTINS_LOCATION, FIELD_DECL,
- NULL_TREE, integer_type_node);
- DECL_CHAIN (fld_flg) = fields;
- fields = fld_flg;
-
- tree fld_cnt = build_decl (BUILTINS_LOCATION, FIELD_DECL,
- NULL_TREE, integer_type_node);
- DECL_CHAIN (fld_cnt) = fields;
- fields = fld_cnt;
-
- /* Create the array of __base_class_type_info entries. */
- tree domain = build_index_type (size_int (num_bases - 1));
- tree array = build_array_type (get_tinfo_desc (TK_BASE_TYPE)->type,
- domain);
- tree fld_ary = build_decl (BUILTINS_LOCATION, FIELD_DECL,
- NULL_TREE, array);
- DECL_CHAIN (fld_ary) = fields;
- fields = fld_ary;
- break;
- }
- }
-
- /* Generate the pseudo type name. */
- const char *real_name = tinfo_names[ix < TK_VMI_CLASS_TYPES
- ? ix : unsigned (TK_VMI_CLASS_TYPES)];
- size_t name_len = strlen (real_name);
- char *pseudo_name = (char *) alloca (name_len + 30);
- memcpy (pseudo_name, real_name, name_len);
- /* Those >= TK_VMI_CLASS_TYPES need a discriminator, may as well
- apply it to all. See get_peudo_tinfo_index where we make use of
- this. */
- sprintf (pseudo_name + name_len, "_pseudo_%d", ix);
-
- /* Create the pseudo type. */
- tree pseudo_type = make_class_type (RECORD_TYPE);
- /* Pass the fields chained in reverse. */
- finish_builtin_struct (pseudo_type, pseudo_name, fields, NULL_TREE);
- CLASSTYPE_AS_BASE (pseudo_type) = pseudo_type;
- DECL_CONTEXT (TYPE_NAME (pseudo_type)) = FROB_CONTEXT (global_namespace);
- DECL_TINFO_P (TYPE_NAME (pseudo_type)) = true;
- xref_basetypes (pseudo_type, /*bases=*/NULL_TREE);
-
- res->type = cp_build_qualified_type (pseudo_type, TYPE_QUAL_CONST);
- res->name = get_identifier (real_name);
-
- /* Pretend this is public so determine_visibility doesn't give vtables
- internal linkage. */
- TREE_PUBLIC (TYPE_MAIN_DECL (res->type)) = 1;
-
- return res;
-}
-
-/* Return an identifying index for the pseudo type_info TYPE.
- We wrote the index at the end of the name, so just scan it from
- there. This isn't critical, as it's only on the first use of this
- type during module stream out. */
-
-unsigned
-get_pseudo_tinfo_index (tree type)
-{
- tree name = DECL_NAME (TYPE_NAME (type));
- unsigned ix = 0, scale = 1;
- size_t len = IDENTIFIER_LENGTH (name);
- const char *ptr = IDENTIFIER_POINTER (name) + len;
-
- for (; *--ptr != '_'; scale *= 10)
- {
- len--;
- gcc_checking_assert (len && ISDIGIT (*ptr));
- ix += (*ptr - '0') * scale;
- }
-
- gcc_assert (len != IDENTIFIER_LENGTH (name));
- return ix;
-}
-
-tree
-get_pseudo_tinfo_type (unsigned ix)
-{
- return get_tinfo_desc (ix)->type;
-}
-
-/* We lazily create the type info types. */
-
-static void
-create_tinfo_types (void)
-{
- gcc_assert (!tinfo_descs);
-
- vec_alloc (tinfo_descs, TK_MAX + 20);
-}
-
-/* Helper for emit_support_tinfos. Emits the type_info descriptor of
- a single type. */
-
-void
-emit_support_tinfo_1 (tree bltn)
-{
- tree types[3];
-
- if (bltn == NULL_TREE)
- return;
- types[0] = bltn;
- types[1] = build_pointer_type (bltn);
- types[2] = build_pointer_type (cp_build_qualified_type (bltn,
- TYPE_QUAL_CONST));
-
- for (int i = 0; i < 3; ++i)
- {
- tree tinfo = get_tinfo_decl (types[i]);
- TREE_USED (tinfo) = 1;
- mark_needed (tinfo);
- /* The C++ ABI requires that these objects be COMDAT. But,
- On systems without weak symbols, initialized COMDAT
- objects are emitted with internal linkage. (See
- comdat_linkage for details.) Since we want these objects
- to have external linkage so that copies do not have to be
- emitted in code outside the runtime library, we make them
- non-COMDAT here.
-
- It might also not be necessary to follow this detail of the
- ABI. */
- if (!flag_weak || ! targetm.cxx.library_rtti_comdat ())
- {
- gcc_assert (TREE_PUBLIC (tinfo) && !DECL_COMDAT (tinfo));
- DECL_INTERFACE_KNOWN (tinfo) = 1;
- }
- }
-}
-
-/* Emit the type_info descriptors which are guaranteed to be in the runtime
- support. Generating them here guarantees consistency with the other
- structures. We use the following heuristic to determine when the runtime
- is being generated. If std::__fundamental_type_info is defined, and its
- destructor is defined, then the runtime is being built. */
-
-void
-emit_support_tinfos (void)
-{
- /* Dummy static variable so we can put nullptr in the array; it will be
- set before we actually start to walk the array. */
- static tree *const fundamentals[] =
- {
- &void_type_node,
- &boolean_type_node,
- &wchar_type_node, &char8_type_node, &char16_type_node, &char32_type_node,
- &char_type_node, &signed_char_type_node, &unsigned_char_type_node,
- &short_integer_type_node, &short_unsigned_type_node,
- &integer_type_node, &unsigned_type_node,
- &long_integer_type_node, &long_unsigned_type_node,
- &long_long_integer_type_node, &long_long_unsigned_type_node,
- &float_type_node, &double_type_node, &long_double_type_node,
- &dfloat32_type_node, &dfloat64_type_node, &dfloat128_type_node,
- &nullptr_type_node,
- 0
- };
- int ix;
-
- /* Look for a defined class. */
- tree bltn_type = lookup_qualified_name
- (abi_node, "__fundamental_type_info", LOOK_want::TYPE, false);
- if (TREE_CODE (bltn_type) != TYPE_DECL)
- return;
-
- bltn_type = TREE_TYPE (bltn_type);
- if (!COMPLETE_TYPE_P (bltn_type))
- return;
- tree dtor = CLASSTYPE_DESTRUCTOR (bltn_type);
- if (!dtor || DECL_EXTERNAL (dtor))
- return;
-
- /* All these are really builtins. So set the location. */
- location_t saved_loc = input_location;
- input_location = BUILTINS_LOCATION;
- doing_runtime = 1;
- for (ix = 0; fundamentals[ix]; ix++)
- emit_support_tinfo_1 (*fundamentals[ix]);
- for (ix = 0; ix < NUM_INT_N_ENTS; ix ++)
- if (int_n_enabled_p[ix])
- {
- emit_support_tinfo_1 (int_n_trees[ix].signed_type);
- emit_support_tinfo_1 (int_n_trees[ix].unsigned_type);
- }
- for (tree t = registered_builtin_types; t; t = TREE_CHAIN (t))
- emit_support_tinfo_1 (TREE_VALUE (t));
- /* For compatibility, emit DFP typeinfos even when DFP isn't enabled,
- because we've emitted that in the past. */
- if (!targetm.decimal_float_supported_p ())
- {
- gcc_assert (dfloat32_type_node == NULL_TREE
- && dfloat64_type_node == NULL_TREE
- && dfloat128_type_node == NULL_TREE);
- fallback_dfloat32_type = make_node (REAL_TYPE);
- fallback_dfloat64_type = make_node (REAL_TYPE);
- fallback_dfloat128_type = make_node (REAL_TYPE);
- emit_support_tinfo_1 (fallback_dfloat32_type);
- emit_support_tinfo_1 (fallback_dfloat64_type);
- emit_support_tinfo_1 (fallback_dfloat128_type);
- }
- input_location = saved_loc;
-}
-
-/* Finish a type info decl. DECL_PTR is a pointer to an unemitted
- tinfo decl. Determine whether it needs emitting, and if so
- generate the initializer. */
-
-bool
-emit_tinfo_decl (tree decl)
-{
- gcc_assert (DECL_TINFO_P (decl));
-
- tree type = TREE_TYPE (DECL_NAME (decl));
- if (typeinfo_in_lib_p (type))
- {
- if (doing_runtime)
- DECL_EXTERNAL (decl) = 0;
- else
- {
- /* If we're not in the runtime, then DECL (which is already
- DECL_EXTERNAL) will not be defined here. */
- DECL_INTERFACE_KNOWN (decl) = 1;
- return false;
- }
- }
- else if (involves_incomplete_p (type))
- {
- if (!decl_needed_p (decl))
- return false;
- /* If TYPE involves an incomplete class type, then the typeinfo
- object will be emitted with internal linkage. There is no
- way to know whether or not types are incomplete until the end
- of the compilation, so this determination must be deferred
- until this point. */
- TREE_PUBLIC (decl) = 0;
- DECL_EXTERNAL (decl) = 0;
- DECL_INTERFACE_KNOWN (decl) = 1;
- }
-
- import_export_decl (decl);
- if (DECL_NOT_REALLY_EXTERN (decl) && decl_needed_p (decl))
- {
- tree init;
-
- DECL_EXTERNAL (decl) = 0;
- init = get_pseudo_ti_init (type, get_pseudo_ti_index (type));
- DECL_INITIAL (decl) = init;
- mark_used (decl);
- cp_finish_decl (decl, init, false, NULL_TREE, 0);
- /* Avoid targets optionally bumping up the alignment to improve
- vector instruction accesses, tinfo are never accessed this way. */
-#ifdef DATA_ABI_ALIGNMENT
- SET_DECL_ALIGN (decl, DATA_ABI_ALIGNMENT (decl, TYPE_ALIGN (TREE_TYPE (decl))));
- DECL_USER_ALIGN (decl) = true;
-#endif
- return true;
- }
- else
- return false;
-}
-
-#include "gt-cp-rtti.h"
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