| /* 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; |
| |
| /* 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); |
| } |
| |
| /* 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" |