/* Functions related to building classes and their related objects. Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc. Contributed by Michael Tiemann (tiemann@cygnus.com) This file is part of GNU CC. GNU CC 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 2, or (at your option) any later version. GNU CC 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 GNU CC; see the file COPYING. If not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* High-level class interface. */ #include "config.h" #include "system.h" #include "tree.h" #include "cp-tree.h" #include "flags.h" #include "rtl.h" #include "output.h" #include "toplev.h" #include "ggc.h" #include "lex.h" #include "obstack.h" #define obstack_chunk_alloc xmalloc #define obstack_chunk_free free /* The number of nested classes being processed. If we are not in the scope of any class, this is zero. */ int current_class_depth; /* In order to deal with nested classes, we keep a stack of classes. The topmost entry is the innermost class, and is the entry at index CURRENT_CLASS_DEPTH */ typedef struct class_stack_node { /* The name of the class. */ tree name; /* The _TYPE node for the class. */ tree type; /* The access specifier pending for new declarations in the scope of this class. */ tree access; /* If were defining TYPE, the names used in this class. */ splay_tree names_used; }* class_stack_node_t; typedef struct vtbl_init_data_s { /* The base for which we're building initializers. */ tree binfo; /* The binfo for the most-derived type. */ tree derived; /* The negative-index vtable initializers built up so far. These are in order from least negative index to most negative index. */ tree inits; /* The last (i.e., most negative entry in INITS. */ tree* last_init; /* The binfo for the virtual base for which we're building vcall offset initializers. */ tree vbase; /* The functions in vbase for which we have already provided vcall offsets. */ varray_type fns; /* The vtable index of the next vcall or vbase offset. */ tree index; /* Nonzero if we are building the initializer for the primary vtable. */ int primary_vtbl_p; /* Nonzero if we are building the initializer for a construction vtable. */ int ctor_vtbl_p; } vtbl_init_data; /* The type of a function passed to walk_subobject_offsets. */ typedef int (*subobject_offset_fn) PARAMS ((tree, tree, splay_tree)); /* The stack itself. This is an dynamically resized array. The number of elements allocated is CURRENT_CLASS_STACK_SIZE. */ static int current_class_stack_size; static class_stack_node_t current_class_stack; /* An array of all local classes present in this translation unit, in declaration order. */ varray_type local_classes; static tree get_vfield_name PARAMS ((tree)); static void finish_struct_anon PARAMS ((tree)); static tree build_vbase_pointer PARAMS ((tree, tree)); static tree build_vtable_entry PARAMS ((tree, tree, tree, int)); static tree get_vtable_name PARAMS ((tree)); static tree get_derived_offset PARAMS ((tree, tree)); static tree get_basefndecls PARAMS ((tree, tree)); static int build_primary_vtable PARAMS ((tree, tree)); static int build_secondary_vtable PARAMS ((tree, tree)); static tree dfs_finish_vtbls PARAMS ((tree, void *)); static tree dfs_accumulate_vtbl_inits PARAMS ((tree, tree, tree, tree, tree)); static void finish_vtbls PARAMS ((tree)); static void modify_vtable_entry PARAMS ((tree, tree, tree, tree, tree *)); static void add_virtual_function PARAMS ((tree *, tree *, int *, tree, tree)); static tree delete_duplicate_fields_1 PARAMS ((tree, tree)); static void delete_duplicate_fields PARAMS ((tree)); static void finish_struct_bits PARAMS ((tree)); static int alter_access PARAMS ((tree, tree, tree)); static void handle_using_decl PARAMS ((tree, tree)); static int same_signature_p PARAMS ((tree, tree)); static int strictly_overrides PARAMS ((tree, tree)); static void mark_overriders PARAMS ((tree, tree)); static void check_for_override PARAMS ((tree, tree)); static tree dfs_modify_vtables PARAMS ((tree, void *)); static tree modify_all_vtables PARAMS ((tree, int *, tree)); static void determine_primary_base PARAMS ((tree, int *)); static void finish_struct_methods PARAMS ((tree)); static void maybe_warn_about_overly_private_class PARAMS ((tree)); static int field_decl_cmp PARAMS ((const tree *, const tree *)); static int method_name_cmp PARAMS ((const tree *, const tree *)); static tree add_implicitly_declared_members PARAMS ((tree, int, int, int)); static tree fixed_type_or_null PARAMS ((tree, int *)); static tree resolve_address_of_overloaded_function PARAMS ((tree, tree, int, int, int, tree)); static void build_vtable_entry_ref PARAMS ((tree, tree, tree)); static tree build_vtbl_initializer PARAMS ((tree, tree, tree, tree, int *)); static int count_fields PARAMS ((tree)); static int add_fields_to_vec PARAMS ((tree, tree, int)); static void check_bitfield_decl PARAMS ((tree)); static void check_field_decl PARAMS ((tree, tree, int *, int *, int *, int *)); static void check_field_decls PARAMS ((tree, tree *, int *, int *, int *, int *)); static void build_base_field PARAMS ((record_layout_info, tree, int *, unsigned int *, splay_tree)); static void build_base_fields PARAMS ((record_layout_info, int *, splay_tree)); static tree build_vbase_pointer_fields PARAMS ((record_layout_info, int *)); static tree build_vtbl_or_vbase_field PARAMS ((tree, tree, tree, tree, tree, int *)); static void check_methods PARAMS ((tree)); static void remove_zero_width_bit_fields PARAMS ((tree)); static void check_bases PARAMS ((tree, int *, int *, int *)); static void check_bases_and_members PARAMS ((tree, int *)); static tree create_vtable_ptr PARAMS ((tree, int *, int *, tree *, tree *)); static void layout_class_type PARAMS ((tree, int *, int *, tree *, tree *)); static void fixup_pending_inline PARAMS ((tree)); static void fixup_inline_methods PARAMS ((tree)); static void set_primary_base PARAMS ((tree, tree, int *)); static void propagate_binfo_offsets PARAMS ((tree, tree)); static void layout_virtual_bases PARAMS ((tree, splay_tree)); static tree dfs_set_offset_for_unshared_vbases PARAMS ((tree, void *)); static void build_vbase_offset_vtbl_entries PARAMS ((tree, vtbl_init_data *)); static void add_vcall_offset_vtbl_entries_r PARAMS ((tree, vtbl_init_data *)); static void add_vcall_offset_vtbl_entries_1 PARAMS ((tree, vtbl_init_data *)); static void build_vcall_offset_vtbl_entries PARAMS ((tree, vtbl_init_data *)); static void layout_vtable_decl PARAMS ((tree, int)); static tree dfs_find_final_overrider PARAMS ((tree, void *)); static tree find_final_overrider PARAMS ((tree, tree, tree)); static int make_new_vtable PARAMS ((tree, tree)); static void dump_class_hierarchy_r PARAMS ((tree, tree, int)); extern void dump_class_hierarchy PARAMS ((tree)); static tree build_vtable PARAMS ((tree, tree, tree)); static void initialize_vtable PARAMS ((tree, tree)); static void initialize_array PARAMS ((tree, tree)); static void layout_nonempty_base_or_field PARAMS ((record_layout_info, tree, tree, splay_tree)); static unsigned HOST_WIDE_INT end_of_class PARAMS ((tree, int)); static void layout_empty_base PARAMS ((tree, tree, splay_tree)); static void accumulate_vtbl_inits PARAMS ((tree, tree, tree, tree, tree)); static void set_vindex PARAMS ((tree, tree, int *)); static void build_rtti_vtbl_entries PARAMS ((tree, tree, vtbl_init_data *)); static void build_vcall_and_vbase_vtbl_entries PARAMS ((tree, vtbl_init_data *)); static tree dfs_mark_primary_bases PARAMS ((tree, void *)); static void mark_primary_bases PARAMS ((tree)); static void clone_constructors_and_destructors PARAMS ((tree)); static tree build_clone PARAMS ((tree, tree)); static void update_vtable_entry_for_fn PARAMS ((tree, tree, tree, tree *)); static tree copy_virtuals PARAMS ((tree)); static void build_ctor_vtbl_group PARAMS ((tree, tree)); static void build_vtt PARAMS ((tree)); static tree *build_vtt_inits PARAMS ((tree, tree, int, tree *, tree *)); static tree dfs_build_secondary_vptr_vtt_inits PARAMS ((tree, void *)); static tree dfs_fixup_binfo_vtbls PARAMS ((tree, void *)); static tree get_matching_base PARAMS ((tree, tree)); static tree dfs_get_primary_binfo PARAMS ((tree, void*)); static int record_subobject_offset PARAMS ((tree, tree, splay_tree)); static int check_subobject_offset PARAMS ((tree, tree, splay_tree)); static int walk_subobject_offsets PARAMS ((tree, subobject_offset_fn, tree, splay_tree, int)); static void record_subobject_offsets PARAMS ((tree, tree, splay_tree, int)); static int layout_conflict_p PARAMS ((tree, tree, splay_tree, int)); static int splay_tree_compare_integer_csts PARAMS ((splay_tree_key k1, splay_tree_key k2)); /* Variables shared between class.c and call.c. */ #ifdef GATHER_STATISTICS int n_vtables = 0; int n_vtable_entries = 0; int n_vtable_searches = 0; int n_vtable_elems = 0; int n_convert_harshness = 0; int n_compute_conversion_costs = 0; int n_build_method_call = 0; int n_inner_fields_searched = 0; #endif /* Virtual base class layout. */ /* Returns a list of virtual base class pointers as a chain of FIELD_DECLS. */ static tree build_vbase_pointer_fields (rli, empty_p) record_layout_info rli; int *empty_p; { /* Chain to hold all the new FIELD_DECLs which point at virtual base classes. */ tree rec = rli->t; tree vbase_decls = NULL_TREE; tree binfos = TYPE_BINFO_BASETYPES (rec); int n_baseclasses = CLASSTYPE_N_BASECLASSES (rec); tree decl; int i; /* Under the new ABI, there are no vbase pointers in the object. Instead, the offsets are stored in the vtable. */ if (vbase_offsets_in_vtable_p ()) return NULL_TREE; /* Loop over the baseclasses, adding vbase pointers as needed. */ for (i = 0; i < n_baseclasses; i++) { register tree base_binfo = TREE_VEC_ELT (binfos, i); register tree basetype = BINFO_TYPE (base_binfo); if (!COMPLETE_TYPE_P (basetype)) /* This error is now reported in xref_tag, thus giving better location information. */ continue; /* All basetypes are recorded in the association list of the derived type. */ if (TREE_VIA_VIRTUAL (base_binfo)) { int j; const char *name; /* The offset for a virtual base class is only used in computing virtual function tables and for initializing virtual base pointers. It is built once `get_vbase_types' is called. */ /* If this basetype can come from another vbase pointer without an additional indirection, we will share that pointer. If an indirection is involved, we make our own pointer. */ for (j = 0; j < n_baseclasses; j++) { tree other_base_binfo = TREE_VEC_ELT (binfos, j); if (! TREE_VIA_VIRTUAL (other_base_binfo) && binfo_for_vbase (basetype, BINFO_TYPE (other_base_binfo))) goto got_it; } FORMAT_VBASE_NAME (name, basetype); decl = build_vtbl_or_vbase_field (get_identifier (name), get_identifier (VTABLE_BASE), build_pointer_type (basetype), rec, basetype, empty_p); BINFO_VPTR_FIELD (base_binfo) = decl; TREE_CHAIN (decl) = vbase_decls; place_field (rli, decl); vbase_decls = decl; *empty_p = 0; got_it: /* The space this decl occupies has already been accounted for. */ ; } } return vbase_decls; } /* Returns a pointer to the virtual base class of EXP that has the indicated TYPE. EXP is of class type, not a pointer type. */ static tree build_vbase_pointer (exp, type) tree exp, type; { if (vbase_offsets_in_vtable_p ()) { tree vbase; tree vbase_ptr; /* Find the shared copy of TYPE; that's where the vtable offset is recorded. */ vbase = binfo_for_vbase (type, TREE_TYPE (exp)); /* Find the virtual function table pointer. */ vbase_ptr = build_vfield_ref (exp, TREE_TYPE (exp)); /* Compute the location where the offset will lie. */ vbase_ptr = build (PLUS_EXPR, TREE_TYPE (vbase_ptr), vbase_ptr, BINFO_VPTR_FIELD (vbase)); vbase_ptr = build1 (NOP_EXPR, build_pointer_type (ptrdiff_type_node), vbase_ptr); /* Add the contents of this location to EXP. */ return build (PLUS_EXPR, build_pointer_type (type), build_unary_op (ADDR_EXPR, exp, /*noconvert=*/0), build1 (INDIRECT_REF, ptrdiff_type_node, vbase_ptr)); } else { char *name; FORMAT_VBASE_NAME (name, type); return build_component_ref (exp, get_identifier (name), NULL_TREE, 0); } } /* Build multi-level access to EXPR using hierarchy path PATH. CODE is PLUS_EXPR if we are going with the grain, and MINUS_EXPR if we are not (in which case, we cannot traverse virtual baseclass links). TYPE is the type we want this path to have on exit. NONNULL is non-zero if we know (for any reason) that EXPR is not, in fact, zero. */ tree build_vbase_path (code, type, expr, path, nonnull) enum tree_code code; tree type, expr, path; int nonnull; { register int changed = 0; tree last = NULL_TREE, last_virtual = NULL_TREE; int fixed_type_p; tree null_expr = 0, nonnull_expr; tree basetype; tree offset = integer_zero_node; if (BINFO_INHERITANCE_CHAIN (path) == NULL_TREE) return build1 (NOP_EXPR, type, expr); /* We could do better if we had additional logic to convert back to the unconverted type (the static type of the complete object), and then convert back to the type we want. Until that is done, we only optimize if the complete type is the same type as expr has. */ fixed_type_p = resolves_to_fixed_type_p (expr, &nonnull); if (!fixed_type_p && TREE_SIDE_EFFECTS (expr)) expr = save_expr (expr); nonnull_expr = expr; path = reverse_path (path); basetype = BINFO_TYPE (path); while (path) { if (TREE_VIA_VIRTUAL (TREE_VALUE (path))) { last_virtual = BINFO_TYPE (TREE_VALUE (path)); if (code == PLUS_EXPR) { changed = ! fixed_type_p; if (changed) { tree ind; /* We already check for ambiguous things in the caller, just find a path. */ if (last) { tree binfo = get_binfo (last, TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (nonnull_expr))), 0); nonnull_expr = convert_pointer_to_real (binfo, nonnull_expr); } ind = build_indirect_ref (nonnull_expr, NULL_PTR); nonnull_expr = build_vbase_pointer (ind, last_virtual); if (nonnull == 0 && TREE_CODE (type) == POINTER_TYPE && null_expr == NULL_TREE) { null_expr = build1 (NOP_EXPR, build_pointer_type (last_virtual), integer_zero_node); expr = build (COND_EXPR, build_pointer_type (last_virtual), build (EQ_EXPR, boolean_type_node, expr, integer_zero_node), null_expr, nonnull_expr); } } /* else we'll figure out the offset below. */ /* Happens in the case of parse errors. */ if (nonnull_expr == error_mark_node) return error_mark_node; } else { cp_error ("cannot cast up from virtual baseclass `%T'", last_virtual); return error_mark_node; } } last = TREE_VALUE (path); path = TREE_CHAIN (path); } /* LAST is now the last basetype assoc on the path. */ /* A pointer to a virtual base member of a non-null object is non-null. Therefore, we only need to test for zeroness once. Make EXPR the canonical expression to deal with here. */ if (null_expr) { TREE_OPERAND (expr, 2) = nonnull_expr; TREE_TYPE (expr) = TREE_TYPE (TREE_OPERAND (expr, 1)) = TREE_TYPE (nonnull_expr); } else expr = nonnull_expr; /* If we go through any virtual base pointers, make sure that casts to BASETYPE from the last virtual base class use the right value for BASETYPE. */ if (changed) { tree intype = TREE_TYPE (TREE_TYPE (expr)); if (TYPE_MAIN_VARIANT (intype) != BINFO_TYPE (last)) offset = BINFO_OFFSET (get_binfo (last, TYPE_MAIN_VARIANT (intype), 0)); } else offset = BINFO_OFFSET (last); if (! integer_zerop (offset)) { /* Bash types to make the backend happy. */ offset = cp_convert (type, offset); /* If expr might be 0, we need to preserve that zeroness. */ if (nonnull == 0) { if (null_expr) TREE_TYPE (null_expr) = type; else null_expr = build1 (NOP_EXPR, type, integer_zero_node); if (TREE_SIDE_EFFECTS (expr)) expr = save_expr (expr); return build (COND_EXPR, type, build (EQ_EXPR, boolean_type_node, expr, integer_zero_node), null_expr, build (code, type, expr, offset)); } else return build (code, type, expr, offset); } /* Cannot change the TREE_TYPE of a NOP_EXPR here, since it may be used multiple times in initialization of multiple inheritance. */ if (null_expr) { TREE_TYPE (expr) = type; return expr; } else return build1 (NOP_EXPR, type, expr); } /* Virtual function things. */ /* We want to give the assembler the vtable identifier as well as the offset to the function pointer. So we generate __asm__ __volatile__ (".vtable_entry %c0, %c1" : : "s"(&class_vtable), "i"((long)&vtbl[idx].pfn - (long)&vtbl[0])); */ static void build_vtable_entry_ref (basetype, vtbl, idx) tree basetype, vtbl, idx; { static char asm_stmt[] = ".vtable_entry %c0, %c1"; tree s, i, i2; s = build_unary_op (ADDR_EXPR, get_vtbl_decl_for_binfo (TYPE_BINFO (basetype)), 0); s = build_tree_list (build_string (1, "s"), s); i = build_array_ref (vtbl, idx); if (!flag_vtable_thunks) i = build_component_ref (i, pfn_identifier, vtable_entry_type, 0); i = build_c_cast (ptrdiff_type_node, build_unary_op (ADDR_EXPR, i, 0)); i2 = build_array_ref (vtbl, build_int_2(0,0)); i2 = build_c_cast (ptrdiff_type_node, build_unary_op (ADDR_EXPR, i2, 0)); i = cp_build_binary_op (MINUS_EXPR, i, i2); i = build_tree_list (build_string (1, "i"), i); finish_asm_stmt (ridpointers[RID_VOLATILE], build_string (sizeof(asm_stmt)-1, asm_stmt), NULL_TREE, chainon (s, i), NULL_TREE); } /* Given an object INSTANCE, return an expression which yields the virtual function vtable element corresponding to INDEX. There are many special cases for INSTANCE which we take care of here, mainly to avoid creating extra tree nodes when we don't have to. */ tree build_vtbl_ref (instance, idx) tree instance, idx; { tree vtbl, aref; tree basetype = TREE_TYPE (instance); if (TREE_CODE (basetype) == REFERENCE_TYPE) basetype = TREE_TYPE (basetype); if (instance == current_class_ref) vtbl = build_vfield_ref (instance, basetype); else { if (optimize) { /* Try to figure out what a reference refers to, and access its virtual function table directly. */ tree ref = NULL_TREE; if (TREE_CODE (instance) == INDIRECT_REF && TREE_CODE (TREE_TYPE (TREE_OPERAND (instance, 0))) == REFERENCE_TYPE) ref = TREE_OPERAND (instance, 0); else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE) ref = instance; if (ref && TREE_CODE (ref) == VAR_DECL && DECL_INITIAL (ref)) { tree init = DECL_INITIAL (ref); while (TREE_CODE (init) == NOP_EXPR || TREE_CODE (init) == NON_LVALUE_EXPR) init = TREE_OPERAND (init, 0); if (TREE_CODE (init) == ADDR_EXPR) { init = TREE_OPERAND (init, 0); if (IS_AGGR_TYPE (TREE_TYPE (init)) && (TREE_CODE (init) == PARM_DECL || TREE_CODE (init) == VAR_DECL)) instance = init; } } } if (IS_AGGR_TYPE (TREE_TYPE (instance)) && (TREE_CODE (instance) == RESULT_DECL || TREE_CODE (instance) == PARM_DECL || TREE_CODE (instance) == VAR_DECL)) { vtbl = TYPE_BINFO_VTABLE (basetype); /* Knowing the dynamic type of INSTANCE we can easily obtain the correct vtable entry. In the new ABI, we resolve this back to be in terms of the primary vtable. */ if (TREE_CODE (vtbl) == PLUS_EXPR) { idx = fold (build (PLUS_EXPR, TREE_TYPE (idx), idx, build (EXACT_DIV_EXPR, TREE_TYPE (idx), TREE_OPERAND (vtbl, 1), TYPE_SIZE_UNIT (vtable_entry_type)))); vtbl = get_vtbl_decl_for_binfo (TYPE_BINFO (basetype)); } } else vtbl = build_vfield_ref (instance, basetype); } assemble_external (vtbl); if (flag_vtable_gc) build_vtable_entry_ref (basetype, vtbl, idx); aref = build_array_ref (vtbl, idx); return aref; } /* Given an object INSTANCE, return an expression which yields the virtual function corresponding to INDEX. There are many special cases for INSTANCE which we take care of here, mainly to avoid creating extra tree nodes when we don't have to. */ tree build_vfn_ref (ptr_to_instptr, instance, idx) tree *ptr_to_instptr, instance; tree idx; { tree aref = build_vtbl_ref (instance, idx); /* When using thunks, there is no extra delta, and we get the pfn directly. */ if (flag_vtable_thunks) return aref; if (ptr_to_instptr) { /* Save the intermediate result in a SAVE_EXPR so we don't have to compute each component of the virtual function pointer twice. */ if (TREE_CODE (aref) == INDIRECT_REF) TREE_OPERAND (aref, 0) = save_expr (TREE_OPERAND (aref, 0)); *ptr_to_instptr = build (PLUS_EXPR, TREE_TYPE (*ptr_to_instptr), *ptr_to_instptr, cp_convert (ptrdiff_type_node, build_component_ref (aref, delta_identifier, NULL_TREE, 0))); } return build_component_ref (aref, pfn_identifier, NULL_TREE, 0); } /* Return the name of the virtual function table (as an IDENTIFIER_NODE) for the given TYPE. */ static tree get_vtable_name (type) tree type; { if (flag_new_abi) return mangle_vtbl_for_type (type); else return build_overload_with_type (get_identifier (VTABLE_NAME_PREFIX), type); } /* Return an IDENTIFIER_NODE for the name of the virtual table table for TYPE. */ tree get_vtt_name (type) tree type; { if (flag_new_abi) return mangle_vtt_for_type (type); else return build_overload_with_type (get_identifier (VTT_NAME_PREFIX), type); } /* Return the offset to the main vtable for a given base BINFO. */ tree get_vfield_offset (binfo) tree binfo; { return size_binop (PLUS_EXPR, byte_position (TYPE_VFIELD (BINFO_TYPE (binfo))), BINFO_OFFSET (binfo)); } /* Get the offset to the start of the original binfo that we derived this binfo from. If we find TYPE first, return the offset only that far. The shortened search is useful because the this pointer on method calling is expected to point to a DECL_CONTEXT (fndecl) object, and not a baseclass of it. */ static tree get_derived_offset (binfo, type) tree binfo, type; { tree offset1 = get_vfield_offset (TYPE_BINFO (BINFO_TYPE (binfo))); tree offset2; while (!same_type_p (BINFO_TYPE (binfo), type)) binfo = get_primary_binfo (binfo); offset2 = get_vfield_offset (TYPE_BINFO (BINFO_TYPE (binfo))); return size_binop (MINUS_EXPR, offset1, offset2); } /* Create a VAR_DECL for a primary or secondary vtable for CLASS_TYPE. (For a secondary vtable for B-in-D, CLASS_TYPE should be D, not B.) Use NAME for the name of the vtable, and VTABLE_TYPE for its type. */ static tree build_vtable (class_type, name, vtable_type) tree class_type; tree name; tree vtable_type; { tree decl; decl = build_lang_decl (VAR_DECL, name, vtable_type); DECL_CONTEXT (decl) = class_type; DECL_ARTIFICIAL (decl) = 1; TREE_STATIC (decl) = 1; #ifndef WRITABLE_VTABLES /* Make them READONLY by default. (mrs) */ TREE_READONLY (decl) = 1; #endif DECL_VIRTUAL_P (decl) = 1; import_export_vtable (decl, class_type, 0); return decl; } /* Get the VAR_DECL of the vtable for TYPE. TYPE need not be polymorphic, or even complete. If this does not exist, create it. If COMPLETE is non-zero, then complete the definition of it -- that will render it impossible to actually build the vtable, but is useful to get at those which are known to exist in the runtime. */ tree get_vtable_decl (type, complete) tree type; int complete; { tree name = get_vtable_name (type); tree decl = IDENTIFIER_GLOBAL_VALUE (name); if (decl) { my_friendly_assert (TREE_CODE (decl) == VAR_DECL && DECL_VIRTUAL_P (decl), 20000118); return decl; } decl = build_vtable (type, name, void_type_node); decl = pushdecl_top_level (decl); my_friendly_assert (IDENTIFIER_GLOBAL_VALUE (name) == decl, 20000517); /* At one time the vtable info was grabbed 2 words at a time. This fails on sparc unless you have 8-byte alignment. (tiemann) */ DECL_ALIGN (decl) = MAX (TYPE_ALIGN (double_type_node), DECL_ALIGN (decl)); if (complete) { DECL_EXTERNAL (decl) = 1; cp_finish_decl (decl, NULL_TREE, NULL_TREE, 0); } return decl; } /* Returns a copy of the BINFO_VIRTUALS list in BINFO. The BV_VCALL_INDEX for each entry is cleared. */ static tree copy_virtuals (binfo) tree binfo; { tree copies; tree t; copies = copy_list (BINFO_VIRTUALS (binfo)); for (t = copies; t; t = TREE_CHAIN (t)) { BV_VCALL_INDEX (t) = NULL_TREE; BV_USE_VCALL_INDEX_P (t) = 0; BV_GENERATE_THUNK_WITH_VTABLE_P (t) = 0; } return copies; } /* Build the primary virtual function table for TYPE. If BINFO is non-NULL, build the vtable starting with the initial approximation that it is the same as the one which is the head of the association list. Returns a non-zero value if a new vtable is actually created. */ static int build_primary_vtable (binfo, type) tree binfo, type; { tree decl; tree virtuals; decl = get_vtable_decl (type, /*complete=*/0); if (binfo) { if (BINFO_NEW_VTABLE_MARKED (binfo, type)) /* We have already created a vtable for this base, so there's no need to do it again. */ return 0; virtuals = copy_virtuals (binfo); TREE_TYPE (decl) = TREE_TYPE (get_vtbl_decl_for_binfo (binfo)); DECL_SIZE (decl) = TYPE_SIZE (TREE_TYPE (decl)); DECL_SIZE_UNIT (decl) = TYPE_SIZE_UNIT (TREE_TYPE (decl)); } else { my_friendly_assert (TREE_CODE (TREE_TYPE (decl)) == VOID_TYPE, 20000118); virtuals = NULL_TREE; } #ifdef GATHER_STATISTICS n_vtables += 1; n_vtable_elems += list_length (virtuals); #endif /* Initialize the association list for this type, based on our first approximation. */ TYPE_BINFO_VTABLE (type) = decl; TYPE_BINFO_VIRTUALS (type) = virtuals; SET_BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (type), type); return 1; } /* Give TYPE a new virtual function table which is initialized with a skeleton-copy of its original initialization. The only entry that changes is the `delta' entry, so we can really share a lot of structure. FOR_TYPE is the derived type which caused this table to be needed. BINFO is the type association which provided TYPE for FOR_TYPE. The order in which vtables are built (by calling this function) for an object must remain the same, otherwise a binary incompatibility can result. */ static int build_secondary_vtable (binfo, for_type) tree binfo, for_type; { tree basetype; tree orig_decl = BINFO_VTABLE (binfo); tree name; tree new_decl; tree offset; tree path = binfo; char *buf; const char *buf2; char joiner = '_'; int i; #ifdef JOINER joiner = JOINER; #endif if (TREE_VIA_VIRTUAL (binfo)) my_friendly_assert (binfo == binfo_for_vbase (BINFO_TYPE (binfo), current_class_type), 170); if (BINFO_NEW_VTABLE_MARKED (binfo, current_class_type)) /* We already created a vtable for this base. There's no need to do it again. */ return 0; /* Remember that we've created a vtable for this BINFO, so that we don't try to do so again. */ SET_BINFO_NEW_VTABLE_MARKED (binfo, current_class_type); /* Make fresh virtual list, so we can smash it later. */ BINFO_VIRTUALS (binfo) = copy_virtuals (binfo); if (TREE_VIA_VIRTUAL (binfo)) { tree binfo1 = binfo_for_vbase (BINFO_TYPE (binfo), for_type); /* XXX - This should never happen, if it does, the caller should ensure that the binfo is from for_type's binfos, not from any base type's. We can remove all this code after a while. */ if (binfo1 != binfo) warning ("internal inconsistency: binfo offset error for rtti"); offset = BINFO_OFFSET (binfo1); } else offset = BINFO_OFFSET (binfo); /* In the new ABI, secondary vtables are laid out as part of the same structure as the primary vtable. */ if (merge_primary_and_secondary_vtables_p ()) { BINFO_VTABLE (binfo) = NULL_TREE; return 1; } /* Create the declaration for the secondary vtable. */ basetype = TYPE_MAIN_VARIANT (BINFO_TYPE (binfo)); buf2 = TYPE_ASSEMBLER_NAME_STRING (basetype); i = TYPE_ASSEMBLER_NAME_LENGTH (basetype) + 1; /* We know that the vtable that we are going to create doesn't exist yet in the global namespace, and when we finish, it will be pushed into the global namespace. In complex MI hierarchies, we have to loop while the name we are thinking of adding is globally defined, adding more name components to the vtable name as we loop, until the name is unique. This is because in complex MI cases, we might have the same base more than once. This means that the order in which this function is called for vtables must remain the same, otherwise binary compatibility can be compromised. */ while (1) { char *buf1 = (char *) alloca (TYPE_ASSEMBLER_NAME_LENGTH (for_type) + 1 + i); char *new_buf2; sprintf (buf1, "%s%c%s", TYPE_ASSEMBLER_NAME_STRING (for_type), joiner, buf2); buf = (char *) alloca (strlen (VTABLE_NAME_PREFIX) + strlen (buf1) + 1); sprintf (buf, "%s%s", VTABLE_NAME_PREFIX, buf1); name = get_identifier (buf); /* If this name doesn't clash, then we can use it, otherwise we add more to the name until it is unique. */ if (! IDENTIFIER_GLOBAL_VALUE (name)) break; /* Set values for next loop through, if the name isn't unique. */ path = BINFO_INHERITANCE_CHAIN (path); /* We better not run out of stuff to make it unique. */ my_friendly_assert (path != NULL_TREE, 368); basetype = TYPE_MAIN_VARIANT (BINFO_TYPE (path)); if (for_type == basetype) { /* If we run out of basetypes in the path, we have already found created a vtable with that name before, we now resort to tacking on _%d to distinguish them. */ int j = 2; i = TYPE_ASSEMBLER_NAME_LENGTH (basetype) + 1 + i + 1 + 3; buf1 = (char *) alloca (i); do { sprintf (buf1, "%s%c%s%c%d", TYPE_ASSEMBLER_NAME_STRING (basetype), joiner, buf2, joiner, j); buf = (char *) alloca (strlen (VTABLE_NAME_PREFIX) + strlen (buf1) + 1); sprintf (buf, "%s%s", VTABLE_NAME_PREFIX, buf1); name = get_identifier (buf); /* If this name doesn't clash, then we can use it, otherwise we add something different to the name until it is unique. */ } while (++j <= 999 && IDENTIFIER_GLOBAL_VALUE (name)); /* Hey, they really like MI don't they? Increase the 3 above to 6, and the 999 to 999999. :-) */ my_friendly_assert (j <= 999, 369); break; } i = TYPE_ASSEMBLER_NAME_LENGTH (basetype) + 1 + i; new_buf2 = (char *) alloca (i); sprintf (new_buf2, "%s%c%s", TYPE_ASSEMBLER_NAME_STRING (basetype), joiner, buf2); buf2 = new_buf2; } new_decl = build_vtable (for_type, name, TREE_TYPE (orig_decl)); DECL_ALIGN (new_decl) = DECL_ALIGN (orig_decl); DECL_USER_ALIGN (new_decl) = DECL_USER_ALIGN (orig_decl); BINFO_VTABLE (binfo) = pushdecl_top_level (new_decl); #ifdef GATHER_STATISTICS n_vtables += 1; n_vtable_elems += list_length (BINFO_VIRTUALS (binfo)); #endif return 1; } /* Create a new vtable for BINFO which is the hierarchy dominated by T. */ static int make_new_vtable (t, binfo) tree t; tree binfo; { if (binfo == TYPE_BINFO (t)) /* In this case, it is *type*'s vtable we are modifying. We start with the approximation that it's vtable is that of the immediate base class. */ return build_primary_vtable (TYPE_BINFO (DECL_CONTEXT (TYPE_VFIELD (t))), t); else /* This is our very own copy of `basetype' to play with. Later, we will fill in all the virtual functions that override the virtual functions in these base classes which are not defined by the current type. */ return build_secondary_vtable (binfo, t); } /* Make *VIRTUALS, an entry on the BINFO_VIRTUALS list for BINFO (which is in the hierarchy dominated by T) list FNDECL as its BV_FN. DELTA is the required constant adjustment from the `this' pointer where the vtable entry appears to the `this' required when the function is actually called. */ static void modify_vtable_entry (t, binfo, fndecl, delta, virtuals) tree t; tree binfo; tree fndecl; tree delta; tree *virtuals; { tree v; v = *virtuals; if (fndecl != BV_FN (v) || !tree_int_cst_equal (delta, BV_DELTA (v))) { tree base_fndecl; /* We need a new vtable for BINFO. */ if (make_new_vtable (t, binfo)) { /* If we really did make a new vtable, we also made a copy of the BINFO_VIRTUALS list. Now, we have to find the corresponding entry in that list. */ *virtuals = BINFO_VIRTUALS (binfo); while (BV_FN (*virtuals) != BV_FN (v)) *virtuals = TREE_CHAIN (*virtuals); v = *virtuals; } base_fndecl = BV_FN (v); BV_DELTA (v) = delta; BV_VCALL_INDEX (v) = NULL_TREE; BV_FN (v) = fndecl; /* Now assign virtual dispatch information, if unset. We can dispatch this, through any overridden base function. */ if (TREE_CODE (DECL_VINDEX (fndecl)) != INTEGER_CST) { DECL_VINDEX (fndecl) = DECL_VINDEX (base_fndecl); DECL_VIRTUAL_CONTEXT (fndecl) = DECL_VIRTUAL_CONTEXT (base_fndecl); } } } /* Return the index (in the virtual function table) of the first virtual function. */ int first_vfun_index (t) tree t; { /* Under the old ABI, the offset-to-top and RTTI entries are at indices zero and one; under the new ABI, the first virtual function is at index zero. */ if (!CLASSTYPE_COM_INTERFACE (t) && !flag_new_abi) return flag_vtable_thunks ? 2 : 1; return 0; } /* Set DECL_VINDEX for DECL. VINDEX_P is the number of virtual functions present in the vtable so far. */ static void set_vindex (t, decl, vfuns_p) tree t; tree decl; int *vfuns_p; { int vindex; vindex = (*vfuns_p)++; vindex += first_vfun_index (t); DECL_VINDEX (decl) = build_shared_int_cst (vindex); } /* Add a virtual function to all the appropriate vtables for the class T. DECL_VINDEX(X) should be error_mark_node, if we want to allocate a new slot in our table. If it is error_mark_node, we know that no other function from another vtable is overridden by X. VFUNS_P keeps track of how many virtuals there are in our main vtable for the type, and we build upon the NEW_VIRTUALS list and return it. */ static void add_virtual_function (new_virtuals_p, overridden_virtuals_p, vfuns_p, fndecl, t) tree *new_virtuals_p; tree *overridden_virtuals_p; int *vfuns_p; tree fndecl; tree t; /* Structure type. */ { tree new_virtual; /* If this function doesn't override anything from a base class, we can just assign it a new DECL_VINDEX now. Otherwise, if it does override something, we keep it around and assign its DECL_VINDEX later, in modify_all_vtables. */ if (TREE_CODE (DECL_VINDEX (fndecl)) == INTEGER_CST) /* We've already dealt with this function. */ return; new_virtual = make_node (TREE_LIST); BV_FN (new_virtual) = fndecl; BV_DELTA (new_virtual) = integer_zero_node; if (DECL_VINDEX (fndecl) == error_mark_node) { /* FNDECL is a new virtual function; it doesn't override any virtual function in a base class. */ /* We remember that this was the base sub-object for rtti. */ CLASSTYPE_RTTI (t) = t; /* Now assign virtual dispatch information. */ set_vindex (t, fndecl, vfuns_p); DECL_VIRTUAL_CONTEXT (fndecl) = t; /* Save the state we've computed on the NEW_VIRTUALS list. */ TREE_CHAIN (new_virtual) = *new_virtuals_p; *new_virtuals_p = new_virtual; } else { /* FNDECL overrides a function from a base class. */ TREE_CHAIN (new_virtual) = *overridden_virtuals_p; *overridden_virtuals_p = new_virtual; } } /* Add method METHOD to class TYPE. If ERROR_P is true, we are adding the method after the class has already been defined because a declaration for it was seen. (Even though that is erroneous, we add the method for improved error recovery.) */ void add_method (type, method, error_p) tree type; tree method; int error_p; { int using = (DECL_CONTEXT (method) != type); int len; int slot; tree method_vec; if (!CLASSTYPE_METHOD_VEC (type)) /* Make a new method vector. We start with 8 entries. We must allocate at least two (for constructors and destructors), and we're going to end up with an assignment operator at some point as well. We could use a TREE_LIST for now, and convert it to a TREE_VEC in finish_struct, but we would probably waste more memory making the links in the list than we would by over-allocating the size of the vector here. Furthermore, we would complicate all the code that expects this to be a vector. */ CLASSTYPE_METHOD_VEC (type) = make_tree_vec (8); method_vec = CLASSTYPE_METHOD_VEC (type); len = TREE_VEC_LENGTH (method_vec); /* Constructors and destructors go in special slots. */ if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (method)) slot = CLASSTYPE_CONSTRUCTOR_SLOT; else if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (method)) slot = CLASSTYPE_DESTRUCTOR_SLOT; else { /* See if we already have an entry with this name. */ for (slot = CLASSTYPE_FIRST_CONVERSION_SLOT; slot < len; ++slot) if (!TREE_VEC_ELT (method_vec, slot) || (DECL_NAME (OVL_CURRENT (TREE_VEC_ELT (method_vec, slot))) == DECL_NAME (method))) break; if (slot == len) { /* We need a bigger method vector. */ int new_len; tree new_vec; /* In the non-error case, we are processing a class definition. Double the size of the vector to give room for new methods. */ if (!error_p) new_len = 2 * len; /* In the error case, the vector is already complete. We don't expect many errors, and the rest of the front-end will get confused if there are empty slots in the vector. */ else new_len = len + 1; new_vec = make_tree_vec (new_len); bcopy ((PTR) &TREE_VEC_ELT (method_vec, 0), (PTR) &TREE_VEC_ELT (new_vec, 0), len * sizeof (tree)); len = new_len; method_vec = CLASSTYPE_METHOD_VEC (type) = new_vec; } if (DECL_CONV_FN_P (method) && !TREE_VEC_ELT (method_vec, slot)) { /* Type conversion operators have to come before ordinary methods; add_conversions depends on this to speed up looking for conversion operators. So, if necessary, we slide some of the vector elements up. In theory, this makes this algorithm O(N^2) but we don't expect many conversion operators. */ for (slot = 2; slot < len; ++slot) { tree fn = TREE_VEC_ELT (method_vec, slot); if (!fn) /* There are no more entries in the vector, so we can insert the new conversion operator here. */ break; if (!DECL_CONV_FN_P (OVL_CURRENT (fn))) /* We can insert the new function right at the SLOTth position. */ break; } if (!TREE_VEC_ELT (method_vec, slot)) /* There is nothing in the Ith slot, so we can avoid moving anything. */ ; else { /* We know the last slot in the vector is empty because we know that at this point there's room for a new function. */ bcopy ((PTR) &TREE_VEC_ELT (method_vec, slot), (PTR) &TREE_VEC_ELT (method_vec, slot + 1), (len - slot - 1) * sizeof (tree)); TREE_VEC_ELT (method_vec, slot) = NULL_TREE; } } } if (template_class_depth (type)) /* TYPE is a template class. Don't issue any errors now; wait until instantiation time to complain. */ ; else { tree fns; /* Check to see if we've already got this method. */ for (fns = TREE_VEC_ELT (method_vec, slot); fns; fns = OVL_NEXT (fns)) { tree fn = OVL_CURRENT (fns); if (TREE_CODE (fn) != TREE_CODE (method)) continue; if (TREE_CODE (method) != TEMPLATE_DECL) { /* [over.load] Member function declarations with the same name and the same parameter types cannot be overloaded if any of them is a static member function declaration. */ if ((DECL_STATIC_FUNCTION_P (fn) != DECL_STATIC_FUNCTION_P (method)) || using) { tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (fn)); tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (method)); if (! DECL_STATIC_FUNCTION_P (fn)) parms1 = TREE_CHAIN (parms1); if (! DECL_STATIC_FUNCTION_P (method)) parms2 = TREE_CHAIN (parms2); if (compparms (parms1, parms2)) { if (using) /* Defer to the local function. */ return; else cp_error ("`%#D' and `%#D' cannot be overloaded", fn, method); } } /* Since this is an ordinary function in a non-template class, it's mangled name can be used as a unique identifier. This technique is only an optimization; we would get the same results if we just used decls_match here. */ if (DECL_ASSEMBLER_NAME (fn) != DECL_ASSEMBLER_NAME (method)) continue; } else if (!decls_match (fn, method)) continue; /* There has already been a declaration of this method or member template. */ cp_error_at ("`%D' has already been declared in `%T'", method, type); /* We don't call duplicate_decls here to merge the declarations because that will confuse things if the methods have inline definitions. In particular, we will crash while processing the definitions. */ return; } } /* Actually insert the new method. */ TREE_VEC_ELT (method_vec, slot) = build_overload (method, TREE_VEC_ELT (method_vec, slot)); /* Add the new binding. */ if (!DECL_CONSTRUCTOR_P (method) && !DECL_DESTRUCTOR_P (method)) push_class_level_binding (DECL_NAME (method), TREE_VEC_ELT (method_vec, slot)); } /* Subroutines of finish_struct. */ /* Look through the list of fields for this struct, deleting duplicates as we go. This must be recursive to handle anonymous unions. FIELD is the field which may not appear anywhere in FIELDS. FIELD_PTR, if non-null, is the starting point at which chained deletions may take place. The value returned is the first acceptable entry found in FIELDS. Note that anonymous fields which are not of UNION_TYPE are not duplicates, they are just anonymous fields. This happens when we have unnamed bitfields, for example. */ static tree delete_duplicate_fields_1 (field, fields) tree field, fields; { tree x; tree prev = 0; if (DECL_NAME (field) == 0) { if (! ANON_AGGR_TYPE_P (TREE_TYPE (field))) return fields; for (x = TYPE_FIELDS (TREE_TYPE (field)); x; x = TREE_CHAIN (x)) fields = delete_duplicate_fields_1 (x, fields); return fields; } else { for (x = fields; x; prev = x, x = TREE_CHAIN (x)) { if (DECL_NAME (x) == 0) { if (! ANON_AGGR_TYPE_P (TREE_TYPE (x))) continue; TYPE_FIELDS (TREE_TYPE (x)) = delete_duplicate_fields_1 (field, TYPE_FIELDS (TREE_TYPE (x))); if (TYPE_FIELDS (TREE_TYPE (x)) == 0) { if (prev == 0) fields = TREE_CHAIN (fields); else TREE_CHAIN (prev) = TREE_CHAIN (x); } } else if (TREE_CODE (field) == USING_DECL) /* A using declaration may is allowed to appear more than once. We'll prune these from the field list later, and handle_using_decl will complain about invalid multiple uses. */ ; else if (DECL_NAME (field) == DECL_NAME (x)) { if (TREE_CODE (field) == CONST_DECL && TREE_CODE (x) == CONST_DECL) cp_error_at ("duplicate enum value `%D'", x); else if (TREE_CODE (field) == CONST_DECL || TREE_CODE (x) == CONST_DECL) cp_error_at ("duplicate field `%D' (as enum and non-enum)", x); else if (DECL_DECLARES_TYPE_P (field) && DECL_DECLARES_TYPE_P (x)) { if (same_type_p (TREE_TYPE (field), TREE_TYPE (x))) continue; cp_error_at ("duplicate nested type `%D'", x); } else if (DECL_DECLARES_TYPE_P (field) || DECL_DECLARES_TYPE_P (x)) { /* Hide tag decls. */ if ((TREE_CODE (field) == TYPE_DECL && DECL_ARTIFICIAL (field)) || (TREE_CODE (x) == TYPE_DECL && DECL_ARTIFICIAL (x))) continue; cp_error_at ("duplicate field `%D' (as type and non-type)", x); } else cp_error_at ("duplicate member `%D'", x); if (prev == 0) fields = TREE_CHAIN (fields); else TREE_CHAIN (prev) = TREE_CHAIN (x); } } } return fields; } static void delete_duplicate_fields (fields) tree fields; { tree x; for (x = fields; x && TREE_CHAIN (x); x = TREE_CHAIN (x)) TREE_CHAIN (x) = delete_duplicate_fields_1 (x, TREE_CHAIN (x)); } /* Change the access of FDECL to ACCESS in T. Return 1 if change was legit, otherwise return 0. */ static int alter_access (t, fdecl, access) tree t; tree fdecl; tree access; { tree elem; if (!DECL_LANG_SPECIFIC (fdecl)) retrofit_lang_decl (fdecl); elem = purpose_member (t, DECL_ACCESS (fdecl)); if (elem) { if (TREE_VALUE (elem) != access) { if (TREE_CODE (TREE_TYPE (fdecl)) == FUNCTION_DECL) cp_error_at ("conflicting access specifications for method `%D', ignored", TREE_TYPE (fdecl)); else error ("conflicting access specifications for field `%s', ignored", IDENTIFIER_POINTER (DECL_NAME (fdecl))); } else { /* They're changing the access to the same thing they changed it to before. That's OK. */ ; } } else { enforce_access (t, fdecl); DECL_ACCESS (fdecl) = tree_cons (t, access, DECL_ACCESS (fdecl)); return 1; } return 0; } /* Process the USING_DECL, which is a member of T. */ static void handle_using_decl (using_decl, t) tree using_decl; tree t; { tree ctype = DECL_INITIAL (using_decl); tree name = DECL_NAME (using_decl); tree access = TREE_PRIVATE (using_decl) ? access_private_node : TREE_PROTECTED (using_decl) ? access_protected_node : access_public_node; tree fdecl, binfo; tree flist = NULL_TREE; tree old_value; binfo = binfo_or_else (ctype, t); if (! binfo) return; if (name == constructor_name (ctype) || name == constructor_name_full (ctype)) { cp_error_at ("using-declaration for constructor", using_decl); return; } fdecl = lookup_member (binfo, name, 0, 0); if (!fdecl) { cp_error_at ("no members matching `%D' in `%#T'", using_decl, ctype); return; } if (BASELINK_P (fdecl)) /* Ignore base type this came from. */ fdecl = TREE_VALUE (fdecl); old_value = IDENTIFIER_CLASS_VALUE (name); if (old_value) { if (is_overloaded_fn (old_value)) old_value = OVL_CURRENT (old_value); if (DECL_P (old_value) && DECL_CONTEXT (old_value) == t) /* OK */; else old_value = NULL_TREE; } if (is_overloaded_fn (fdecl)) flist = fdecl; if (! old_value) ; else if (is_overloaded_fn (old_value)) { if (flist) /* It's OK to use functions from a base when there are functions with the same name already present in the current class. */; else { cp_error ("`%D' invalid in `%#T'", using_decl, t); cp_error_at (" because of local method `%#D' with same name", OVL_CURRENT (old_value)); return; } } else { cp_error ("`%D' invalid in `%#T'", using_decl, t); cp_error_at (" because of local field `%#D' with same name", old_value); return; } /* Make type T see field decl FDECL with access ACCESS.*/ if (flist) for (; flist; flist = OVL_NEXT (flist)) { add_method (t, OVL_CURRENT (flist), /*error_p=*/0); alter_access (t, OVL_CURRENT (flist), access); } else alter_access (t, fdecl, access); } /* Run through the base clases of T, updating CANT_HAVE_DEFAULT_CTOR_P, CANT_HAVE_CONST_CTOR_P, and NO_CONST_ASN_REF_P. Also set flag bits in T based on properties of the bases. */ static void check_bases (t, cant_have_default_ctor_p, cant_have_const_ctor_p, no_const_asn_ref_p) tree t; int *cant_have_default_ctor_p; int *cant_have_const_ctor_p; int *no_const_asn_ref_p; { int n_baseclasses; int i; int seen_nearly_empty_base_p; tree binfos; binfos = TYPE_BINFO_BASETYPES (t); n_baseclasses = CLASSTYPE_N_BASECLASSES (t); seen_nearly_empty_base_p = 0; /* An aggregate cannot have baseclasses. */ CLASSTYPE_NON_AGGREGATE (t) |= (n_baseclasses != 0); for (i = 0; i < n_baseclasses; ++i) { tree base_binfo; tree basetype; /* Figure out what base we're looking at. */ base_binfo = TREE_VEC_ELT (binfos, i); basetype = TREE_TYPE (base_binfo); /* If the type of basetype is incomplete, then we already complained about that fact (and we should have fixed it up as well). */ if (!COMPLETE_TYPE_P (basetype)) { int j; /* The base type is of incomplete type. It is probably best to pretend that it does not exist. */ if (i == n_baseclasses-1) TREE_VEC_ELT (binfos, i) = NULL_TREE; TREE_VEC_LENGTH (binfos) -= 1; n_baseclasses -= 1; for (j = i; j+1 < n_baseclasses; j++) TREE_VEC_ELT (binfos, j) = TREE_VEC_ELT (binfos, j+1); continue; } /* Effective C++ rule 14. We only need to check TYPE_POLYMORPHIC_P here because the case of virtual functions but non-virtual dtor is handled in finish_struct_1. */ if (warn_ecpp && ! TYPE_POLYMORPHIC_P (basetype) && TYPE_HAS_DESTRUCTOR (basetype)) cp_warning ("base class `%#T' has a non-virtual destructor", basetype); /* If the base class doesn't have copy constructors or assignment operators that take const references, then the derived class cannot have such a member automatically generated. */ if (! TYPE_HAS_CONST_INIT_REF (basetype)) *cant_have_const_ctor_p = 1; if (TYPE_HAS_ASSIGN_REF (basetype) && !TYPE_HAS_CONST_ASSIGN_REF (basetype)) *no_const_asn_ref_p = 1; /* Similarly, if the base class doesn't have a default constructor, then the derived class won't have an automatically generated default constructor. */ if (TYPE_HAS_CONSTRUCTOR (basetype) && ! TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)) { *cant_have_default_ctor_p = 1; if (! TYPE_HAS_CONSTRUCTOR (t)) cp_pedwarn ("base `%T' with only non-default constructor in class without a constructor", basetype); } /* If the base class is not empty or nearly empty, then this class cannot be nearly empty. */ if (!CLASSTYPE_NEARLY_EMPTY_P (basetype) && !is_empty_class (basetype)) CLASSTYPE_NEARLY_EMPTY_P (t) = 0; /* And if there is more than one nearly empty base, then the derived class is not nearly empty either. */ else if (CLASSTYPE_NEARLY_EMPTY_P (basetype) && seen_nearly_empty_base_p) CLASSTYPE_NEARLY_EMPTY_P (t) = 0; /* If this is the first nearly empty base class, then remember that we saw it. */ else if (CLASSTYPE_NEARLY_EMPTY_P (basetype)) seen_nearly_empty_base_p = 1; /* A lot of properties from the bases also apply to the derived class. */ TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (basetype); TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (basetype); TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (basetype); TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (basetype); TYPE_OVERLOADS_CALL_EXPR (t) |= TYPE_OVERLOADS_CALL_EXPR (basetype); TYPE_OVERLOADS_ARRAY_REF (t) |= TYPE_OVERLOADS_ARRAY_REF (basetype); TYPE_OVERLOADS_ARROW (t) |= TYPE_OVERLOADS_ARROW (basetype); TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype); /* Derived classes can implicitly become COMified if their bases are COM. */ if (CLASSTYPE_COM_INTERFACE (basetype)) CLASSTYPE_COM_INTERFACE (t) = 1; else if (i == 0 && CLASSTYPE_COM_INTERFACE (t)) { cp_error ("COM interface type `%T' with non-COM leftmost base class `%T'", t, basetype); CLASSTYPE_COM_INTERFACE (t) = 0; } } } /* Called via dfs_walk from mark_primary_bases. Sets BINFO_PRIMARY_MARKED_P for BINFO, if appropriate. */ static tree dfs_mark_primary_bases (binfo, data) tree binfo; void *data; { tree base_binfo; if (!CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (binfo))) return NULL_TREE; base_binfo = get_primary_binfo (binfo); if (TREE_VIA_VIRTUAL (base_binfo)) { tree shared_binfo; tree type; type = (tree) data; shared_binfo = binfo_for_vbase (BINFO_TYPE (base_binfo), type); /* If this virtual base is not already primary somewhere else in the hiearchy, then we'll be using this copy. */ if (!BINFO_PRIMARY_MARKED_P (shared_binfo)) { /* Make sure the CLASSTYPE_VBASECLASSES list contains the primary copy; it's the one that really exists. */ if (base_binfo != shared_binfo) TREE_VALUE (purpose_member (BINFO_TYPE (base_binfo), CLASSTYPE_VBASECLASSES (type))) = base_binfo; } else base_binfo = NULL_TREE; } if (base_binfo) BINFO_PRIMARY_BASE_OF (base_binfo) = binfo; return NULL_TREE; } /* Set BINFO_PRIMARY_MARKED_P for all binfos in the hierarchy dominated by BINFO that are primary bases. */ static void mark_primary_bases (type) tree type; { tree vbases; /* Mark the TYPE_BINFO hierarchy. We need to mark primary bases in pre-order to deal with primary virtual bases. (The virtual base would be skipped if it were not marked as primary, and that requires getting to dfs_mark_primary_bases before dfs_skip_nonprimary_vbases_unmarkedp has a chance to skip the virtual base.) */ dfs_walk_real (TYPE_BINFO (type), dfs_mark_primary_bases, NULL, dfs_skip_nonprimary_vbases_unmarkedp, type); /* Now go through the virtual base classes in inheritance graph order. Any that are not already primary will need to be allocated in TYPE, and so we need to mark their primary bases. */ for (vbases = TYPE_BINFO (type); vbases; vbases = TREE_CHAIN (vbases)) { tree vbase; /* Make sure that only BINFOs appear on this list. Historically, the TREE_CHAIN was used for other purposes, and we want to make sure that none of those uses remain. */ my_friendly_assert (TREE_CODE (vbases) == TREE_VEC, 20000402); if (!TREE_VIA_VIRTUAL (vbases)) continue; vbase = binfo_for_vbase (BINFO_TYPE (vbases), type); if (BINFO_PRIMARY_MARKED_P (vbase)) /* This virtual base was already included in the hierarchy, so there's nothing to do here. */ continue; /* Now, walk its bases. */ dfs_walk_real (vbase, dfs_mark_primary_bases, NULL, dfs_skip_nonprimary_vbases_unmarkedp, type); } } /* Make the BINFO the primary base of T. */ static void set_primary_base (t, binfo, vfuns_p) tree t; tree binfo; int *vfuns_p; { tree basetype; CLASSTYPE_PRIMARY_BINFO (t) = binfo; basetype = BINFO_TYPE (binfo); TYPE_BINFO_VTABLE (t) = TYPE_BINFO_VTABLE (basetype); TYPE_BINFO_VIRTUALS (t) = TYPE_BINFO_VIRTUALS (basetype); TYPE_VFIELD (t) = TYPE_VFIELD (basetype); CLASSTYPE_RTTI (t) = CLASSTYPE_RTTI (basetype); *vfuns_p = CLASSTYPE_VSIZE (basetype); } /* Determine the primary class for T. */ static void determine_primary_base (t, vfuns_p) tree t; int *vfuns_p; { int i, n_baseclasses = CLASSTYPE_N_BASECLASSES (t); tree vbases; tree type_binfo; /* If there are no baseclasses, there is certainly no primary base. */ if (n_baseclasses == 0) return; type_binfo = TYPE_BINFO (t); for (i = 0; i < n_baseclasses; i++) { tree base_binfo = BINFO_BASETYPE (type_binfo, i); tree basetype = BINFO_TYPE (base_binfo); if (TYPE_CONTAINS_VPTR_P (basetype)) { /* Even a virtual baseclass can contain our RTTI information. But, we prefer a non-virtual polymorphic baseclass. */ if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t)) CLASSTYPE_RTTI (t) = CLASSTYPE_RTTI (basetype); /* A virtual baseclass can't be the primary base under the old ABI. And under the new ABI we still prefer a non-virtual base. */ if (TREE_VIA_VIRTUAL (base_binfo)) continue; if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t)) { set_primary_base (t, base_binfo, vfuns_p); CLASSTYPE_VFIELDS (t) = copy_list (CLASSTYPE_VFIELDS (basetype)); } else { tree vfields; /* Only add unique vfields, and flatten them out as we go. */ for (vfields = CLASSTYPE_VFIELDS (basetype); vfields; vfields = TREE_CHAIN (vfields)) if (VF_BINFO_VALUE (vfields) == NULL_TREE || ! TREE_VIA_VIRTUAL (VF_BINFO_VALUE (vfields))) CLASSTYPE_VFIELDS (t) = tree_cons (base_binfo, VF_BASETYPE_VALUE (vfields), CLASSTYPE_VFIELDS (t)); if (!flag_new_abi && *vfuns_p == 0) set_primary_base (t, base_binfo, vfuns_p); } } } if (!TYPE_VFIELD (t)) CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE; /* Mark the indirect primary bases. */ for (vbases = CLASSTYPE_VBASECLASSES (t); vbases; vbases = TREE_CHAIN (vbases)) { tree binfo = TREE_VALUE (vbases); /* See if this virtual base is an indirect primary base. If so, it must be either a primary base or an indirect primary base in one of the direct bases. */ for (i = 0; i < n_baseclasses; ++i) { tree basetype; tree v; basetype = TYPE_BINFO_BASETYPE (t, i); for (v = CLASSTYPE_VBASECLASSES (basetype); v; v = TREE_CHAIN (v)) { tree b = TREE_VALUE (v); if ((BINFO_PRIMARY_MARKED_P (b) || BINFO_INDIRECT_PRIMARY_P (b)) && same_type_p (BINFO_TYPE (b), BINFO_TYPE (binfo))) { BINFO_INDIRECT_PRIMARY_P (binfo) = 1; break; } } /* If we've discovered that this virtual base is an indirect primary base, then we can move on to the next virtual base. */ if (BINFO_INDIRECT_PRIMARY_P (binfo)) break; } } /* The new ABI allows for the use of a "nearly-empty" virtual base class as the primary base class if no non-virtual polymorphic base can be found. */ if (flag_new_abi && !CLASSTYPE_HAS_PRIMARY_BASE_P (t)) { /* If not NULL, this is the best primary base candidate we have found so far. */ tree candidate = NULL_TREE; tree base_binfo; /* Loop over the baseclasses. */ for (base_binfo = TYPE_BINFO (t); base_binfo; base_binfo = TREE_CHAIN (base_binfo)) { tree basetype = BINFO_TYPE (base_binfo); if (TREE_VIA_VIRTUAL (base_binfo) && CLASSTYPE_NEARLY_EMPTY_P (basetype)) { /* If this is not an indirect primary base, then it's definitely our primary base. */ if (!BINFO_INDIRECT_PRIMARY_P (base_binfo)) { candidate = base_binfo; break; } /* If this was an indirect primary base, it's still our primary base -- unless there's another nearly-empty virtual base that isn't an indirect primary base. */ else if (!candidate) candidate = base_binfo; } } /* If we've got a primary base, use it. */ if (candidate) { set_primary_base (t, candidate, vfuns_p); CLASSTYPE_VFIELDS (t) = copy_list (CLASSTYPE_VFIELDS (BINFO_TYPE (candidate))); } } /* Mark the primary base classes at this point. */ mark_primary_bases (t); } /* Set memoizing fields and bits of T (and its variants) for later use. */ static void finish_struct_bits (t) tree t; { int i, n_baseclasses = CLASSTYPE_N_BASECLASSES (t); /* Fix up variants (if any). */ tree variants = TYPE_NEXT_VARIANT (t); while (variants) { /* These fields are in the _TYPE part of the node, not in the TYPE_LANG_SPECIFIC component, so they are not shared. */ TYPE_HAS_CONSTRUCTOR (variants) = TYPE_HAS_CONSTRUCTOR (t); TYPE_HAS_DESTRUCTOR (variants) = TYPE_HAS_DESTRUCTOR (t); TYPE_NEEDS_CONSTRUCTING (variants) = TYPE_NEEDS_CONSTRUCTING (t); TYPE_HAS_NONTRIVIAL_DESTRUCTOR (variants) = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t); TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (variants) = TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (t); TYPE_POLYMORPHIC_P (variants) = TYPE_POLYMORPHIC_P (t); TYPE_USES_VIRTUAL_BASECLASSES (variants) = TYPE_USES_VIRTUAL_BASECLASSES (t); /* Copy whatever these are holding today. */ TYPE_MIN_VALUE (variants) = TYPE_MIN_VALUE (t); TYPE_MAX_VALUE (variants) = TYPE_MAX_VALUE (t); TYPE_FIELDS (variants) = TYPE_FIELDS (t); TYPE_SIZE (variants) = TYPE_SIZE (t); TYPE_SIZE_UNIT (variants) = TYPE_SIZE_UNIT (t); variants = TYPE_NEXT_VARIANT (variants); } if (n_baseclasses && TYPE_POLYMORPHIC_P (t)) /* For a class w/o baseclasses, `finish_struct' has set CLASS_TYPE_ABSTRACT_VIRTUALS correctly (by definition). Similarly for a class whose base classes do not have vtables. When neither of these is true, we might have removed abstract virtuals (by providing a definition), added some (by declaring new ones), or redeclared ones from a base class. We need to recalculate what's really an abstract virtual at this point (by looking in the vtables). */ get_pure_virtuals (t); if (n_baseclasses) { /* Notice whether this class has type conversion functions defined. */ tree binfo = TYPE_BINFO (t); tree binfos = BINFO_BASETYPES (binfo); tree basetype; for (i = n_baseclasses-1; i >= 0; i--) { basetype = BINFO_TYPE (TREE_VEC_ELT (binfos, i)); TYPE_HAS_CONVERSION (t) |= TYPE_HAS_CONVERSION (basetype); } } /* If this type has a copy constructor, force its mode to be BLKmode, and force its TREE_ADDRESSABLE bit to be nonzero. This will cause it to be passed by invisible reference and prevent it from being returned in a register. Also do this if the class has BLKmode but can still be returned in registers, since function_cannot_inline_p won't let us inline functions returning such a type. This affects the HP-PA. */ if (! TYPE_HAS_TRIVIAL_INIT_REF (t) || (TYPE_MODE (t) == BLKmode && ! aggregate_value_p (t) && CLASSTYPE_NON_AGGREGATE (t))) { tree variants; DECL_MODE (TYPE_MAIN_DECL (t)) = BLKmode; for (variants = t; variants; variants = TYPE_NEXT_VARIANT (variants)) { TYPE_MODE (variants) = BLKmode; TREE_ADDRESSABLE (variants) = 1; } } } /* Issue warnings about T having private constructors, but no friends, and so forth. HAS_NONPRIVATE_METHOD is nonzero if T has any non-private methods or static members. HAS_NONPRIVATE_STATIC_FN is nonzero if T has any non-private static member functions. */ static void maybe_warn_about_overly_private_class (t) tree t; { int has_member_fn = 0; int has_nonprivate_method = 0; tree fn; if (!warn_ctor_dtor_privacy /* If the class has friends, those entities might create and access instances, so we should not warn. */ || (CLASSTYPE_FRIEND_CLASSES (t) || DECL_FRIENDLIST (TYPE_MAIN_DECL (t))) /* We will have warned when the template was declared; there's no need to warn on every instantiation. */ || CLASSTYPE_TEMPLATE_INSTANTIATION (t)) /* There's no reason to even consider warning about this class. */ return; /* We only issue one warning, if more than one applies, because otherwise, on code like: class A { // Oops - forgot `public:' A(); A(const A&); ~A(); }; we warn several times about essentially the same problem. */ /* Check to see if all (non-constructor, non-destructor) member functions are private. (Since there are no friends or non-private statics, we can't ever call any of the private member functions.) */ for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn)) /* We're not interested in compiler-generated methods; they don't provide any way to call private members. */ if (!DECL_ARTIFICIAL (fn)) { if (!TREE_PRIVATE (fn)) { if (DECL_STATIC_FUNCTION_P (fn)) /* A non-private static member function is just like a friend; it can create and invoke private member functions, and be accessed without a class instance. */ return; has_nonprivate_method = 1; break; } else if (!DECL_CONSTRUCTOR_P (fn) && !DECL_DESTRUCTOR_P (fn)) has_member_fn = 1; } if (!has_nonprivate_method && has_member_fn) { /* There are no non-private methods, and there's at least one private member function that isn't a constructor or destructor. (If all the private members are constructors/destructors we want to use the code below that issues error messages specifically referring to constructors/destructors.) */ int i; tree binfos = BINFO_BASETYPES (TYPE_BINFO (t)); for (i = 0; i < CLASSTYPE_N_BASECLASSES (t); i++) if (TREE_VIA_PUBLIC (TREE_VEC_ELT (binfos, i)) || TREE_VIA_PROTECTED (TREE_VEC_ELT (binfos, i))) { has_nonprivate_method = 1; break; } if (!has_nonprivate_method) { cp_warning ("all member functions in class `%T' are private", t); return; } } /* Even if some of the member functions are non-private, the class won't be useful for much if all the constructors or destructors are private: such an object can never be created or destroyed. */ if (TYPE_HAS_DESTRUCTOR (t)) { tree dtor = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (t), 1); if (TREE_PRIVATE (dtor)) { cp_warning ("`%#T' only defines a private destructor and has no friends", t); return; } } if (TYPE_HAS_CONSTRUCTOR (t)) { int nonprivate_ctor = 0; /* If a non-template class does not define a copy constructor, one is defined for it, enabling it to avoid this warning. For a template class, this does not happen, and so we would normally get a warning on: template class C { private: C(); }; To avoid this asymmetry, we check TYPE_HAS_INIT_REF. All complete non-template or fully instantiated classes have this flag set. */ if (!TYPE_HAS_INIT_REF (t)) nonprivate_ctor = 1; else for (fn = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (t), 0); fn; fn = OVL_NEXT (fn)) { tree ctor = OVL_CURRENT (fn); /* Ideally, we wouldn't count copy constructors (or, in fact, any constructor that takes an argument of the class type as a parameter) because such things cannot be used to construct an instance of the class unless you already have one. But, for now at least, we're more generous. */ if (! TREE_PRIVATE (ctor)) { nonprivate_ctor = 1; break; } } if (nonprivate_ctor == 0) { cp_warning ("`%#T' only defines private constructors and has no friends", t); return; } } } /* Function to help qsort sort FIELD_DECLs by name order. */ static int field_decl_cmp (x, y) const tree *x, *y; { if (DECL_NAME (*x) == DECL_NAME (*y)) /* A nontype is "greater" than a type. */ return DECL_DECLARES_TYPE_P (*y) - DECL_DECLARES_TYPE_P (*x); if (DECL_NAME (*x) == NULL_TREE) return -1; if (DECL_NAME (*y) == NULL_TREE) return 1; if (DECL_NAME (*x) < DECL_NAME (*y)) return -1; return 1; } /* Comparison function to compare two TYPE_METHOD_VEC entries by name. */ static int method_name_cmp (m1, m2) const tree *m1, *m2; { if (*m1 == NULL_TREE && *m2 == NULL_TREE) return 0; if (*m1 == NULL_TREE) return -1; if (*m2 == NULL_TREE) return 1; if (DECL_NAME (OVL_CURRENT (*m1)) < DECL_NAME (OVL_CURRENT (*m2))) return -1; return 1; } /* Warn about duplicate methods in fn_fields. Also compact method lists so that lookup can be made faster. Data Structure: List of method lists. The outer list is a TREE_LIST, whose TREE_PURPOSE field is the field name and the TREE_VALUE is the DECL_CHAIN of the FUNCTION_DECLs. TREE_CHAIN links the entire list of methods for TYPE_METHODS. Friends are chained in the same way as member functions (? TREE_CHAIN or DECL_CHAIN), but they live in the TREE_TYPE field of the outer list. That allows them to be quickly deleted, and requires no extra storage. Sort methods that are not special (i.e., constructors, destructors, and type conversion operators) so that we can find them faster in search. */ static void finish_struct_methods (t) tree t; { tree fn_fields; tree method_vec; int slot, len; if (!TYPE_METHODS (t)) { /* Clear these for safety; perhaps some parsing error could set these incorrectly. */ TYPE_HAS_CONSTRUCTOR (t) = 0; TYPE_HAS_DESTRUCTOR (t) = 0; CLASSTYPE_METHOD_VEC (t) = NULL_TREE; return; } method_vec = CLASSTYPE_METHOD_VEC (t); my_friendly_assert (method_vec != NULL_TREE, 19991215); len = TREE_VEC_LENGTH (method_vec); /* First fill in entry 0 with the constructors, entry 1 with destructors, and the next few with type conversion operators (if any). */ for (fn_fields = TYPE_METHODS (t); fn_fields; fn_fields = TREE_CHAIN (fn_fields)) /* Clear out this flag. */ DECL_IN_AGGR_P (fn_fields) = 0; if (TYPE_HAS_DESTRUCTOR (t) && !CLASSTYPE_DESTRUCTORS (t)) /* We thought there was a destructor, but there wasn't. Some parse errors cause this anomalous situation. */ TYPE_HAS_DESTRUCTOR (t) = 0; /* Issue warnings about private constructors and such. If there are no methods, then some public defaults are generated. */ maybe_warn_about_overly_private_class (t); /* Now sort the methods. */ while (len > 2 && TREE_VEC_ELT (method_vec, len-1) == NULL_TREE) len--; TREE_VEC_LENGTH (method_vec) = len; /* The type conversion ops have to live at the front of the vec, so we can't sort them. */ for (slot = 2; slot < len; ++slot) { tree fn = TREE_VEC_ELT (method_vec, slot); if (!DECL_CONV_FN_P (OVL_CURRENT (fn))) break; } if (len - slot > 1) qsort (&TREE_VEC_ELT (method_vec, slot), len-slot, sizeof (tree), (int (*)(const void *, const void *))method_name_cmp); } /* Emit error when a duplicate definition of a type is seen. Patch up. */ void duplicate_tag_error (t) tree t; { cp_error ("redefinition of `%#T'", t); cp_error_at ("previous definition here", t); /* Pretend we haven't defined this type. */ /* All of the component_decl's were TREE_CHAINed together in the parser. finish_struct_methods walks these chains and assembles all methods with the same base name into DECL_CHAINs. Now we don't need the parser chains anymore, so we unravel them. */ /* This used to be in finish_struct, but it turns out that the TREE_CHAIN is used by dbxout_type_methods and perhaps some other things... */ if (CLASSTYPE_METHOD_VEC (t)) { tree method_vec = CLASSTYPE_METHOD_VEC (t); int i, len = TREE_VEC_LENGTH (method_vec); for (i = 0; i < len; i++) { tree unchain = TREE_VEC_ELT (method_vec, i); while (unchain != NULL_TREE) { TREE_CHAIN (OVL_CURRENT (unchain)) = NULL_TREE; unchain = OVL_NEXT (unchain); } } } if (TYPE_LANG_SPECIFIC (t)) { tree binfo = TYPE_BINFO (t); int interface_only = CLASSTYPE_INTERFACE_ONLY (t); int interface_unknown = CLASSTYPE_INTERFACE_UNKNOWN (t); tree template_info = CLASSTYPE_TEMPLATE_INFO (t); int use_template = CLASSTYPE_USE_TEMPLATE (t); bzero ((char *) TYPE_LANG_SPECIFIC (t), sizeof (struct lang_type)); BINFO_BASETYPES(binfo) = NULL_TREE; TYPE_BINFO (t) = binfo; CLASSTYPE_INTERFACE_ONLY (t) = interface_only; SET_CLASSTYPE_INTERFACE_UNKNOWN_X (t, interface_unknown); TYPE_REDEFINED (t) = 1; CLASSTYPE_TEMPLATE_INFO (t) = template_info; CLASSTYPE_USE_TEMPLATE (t) = use_template; } TYPE_SIZE (t) = NULL_TREE; TYPE_MODE (t) = VOIDmode; TYPE_FIELDS (t) = NULL_TREE; TYPE_METHODS (t) = NULL_TREE; TYPE_VFIELD (t) = NULL_TREE; TYPE_CONTEXT (t) = NULL_TREE; TYPE_NONCOPIED_PARTS (t) = NULL_TREE; } /* Make the BINFO's vtablehave N entries, including RTTI entries, vbase and vcall offsets, etc. Set its type and call the backend to lay it out. */ static void layout_vtable_decl (binfo, n) tree binfo; int n; { tree itype; tree atype; tree vtable; itype = size_int (n); atype = build_cplus_array_type (vtable_entry_type, build_index_type (itype)); layout_type (atype); /* We may have to grow the vtable. */ vtable = get_vtbl_decl_for_binfo (binfo); if (!same_type_p (TREE_TYPE (vtable), atype)) { TREE_TYPE (vtable) = atype; DECL_SIZE (vtable) = DECL_SIZE_UNIT (vtable) = NULL_TREE; layout_decl (vtable, 0); /* At one time the vtable info was grabbed 2 words at a time. This fails on Sparc unless you have 8-byte alignment. */ DECL_ALIGN (vtable) = MAX (TYPE_ALIGN (double_type_node), DECL_ALIGN (vtable)); } } /* True iff FNDECL and BASE_FNDECL (both non-static member functions) have the same signature. */ static int same_signature_p (fndecl, base_fndecl) tree fndecl, base_fndecl; { /* One destructor overrides another if they are the same kind of destructor. */ if (DECL_DESTRUCTOR_P (base_fndecl) && DECL_DESTRUCTOR_P (fndecl) && special_function_p (base_fndecl) == special_function_p (fndecl)) return 1; /* But a non-destructor never overrides a destructor, nor vice versa, nor do different kinds of destructors override one-another. For example, a complete object destructor does not override a deleting destructor. */ if (DECL_DESTRUCTOR_P (base_fndecl) || DECL_DESTRUCTOR_P (fndecl)) return 0; if (DECL_NAME (fndecl) == DECL_NAME (base_fndecl)) { tree types, base_types; types = TYPE_ARG_TYPES (TREE_TYPE (fndecl)); base_types = TYPE_ARG_TYPES (TREE_TYPE (base_fndecl)); if ((TYPE_QUALS (TREE_TYPE (TREE_VALUE (base_types))) == TYPE_QUALS (TREE_TYPE (TREE_VALUE (types)))) && compparms (TREE_CHAIN (base_types), TREE_CHAIN (types))) return 1; } return 0; } typedef struct find_final_overrider_data_s { /* The function for which we are trying to find a final overrider. */ tree fn; /* The base class in which the function was declared. */ tree declaring_base; /* The most derived class in the hierarchy. */ tree most_derived_type; /* The final overriding function. */ tree overriding_fn; /* The BINFO for the class in which the final overriding function appears. */ tree overriding_base; } find_final_overrider_data; /* Called from find_final_overrider via dfs_walk. */ static tree dfs_find_final_overrider (binfo, data) tree binfo; void *data; { find_final_overrider_data *ffod = (find_final_overrider_data *) data; if (same_type_p (BINFO_TYPE (binfo), BINFO_TYPE (ffod->declaring_base)) && tree_int_cst_equal (BINFO_OFFSET (binfo), BINFO_OFFSET (ffod->declaring_base))) { tree path; tree method; /* We haven't found an overrider yet. */ method = NULL_TREE; /* We've found a path to the declaring base. Walk down the path looking for an overrider for FN. */ for (path = reverse_path (binfo); path; path = TREE_CHAIN (path)) { for (method = TYPE_METHODS (BINFO_TYPE (TREE_VALUE (path))); method; method = TREE_CHAIN (method)) if (DECL_VIRTUAL_P (method) && same_signature_p (method, ffod->fn)) break; if (method) break; } /* If we found an overrider, record the overriding function, and the base from which it came. */ if (path) { tree base; /* Assume the path is non-virtual. See if there are any virtual bases from (but not including) the overrider up to and including the base where the function is defined. */ for (base = TREE_CHAIN (path); base; base = TREE_CHAIN (base)) if (TREE_VIA_VIRTUAL (TREE_VALUE (base))) { base = ffod->declaring_base; while (BINFO_PRIMARY_MARKED_P (base)) { BINFO_OVERRIDE_ALONG_VIRTUAL_PATH_P (base) = 1; base = BINFO_INHERITANCE_CHAIN (base); } BINFO_OVERRIDE_ALONG_VIRTUAL_PATH_P (base) = 1; break; } if (ffod->overriding_fn && ffod->overriding_fn != method) { /* We've found a different overrider along a different path. That can be OK if the new one overrides the old one. Consider: struct S { virtual void f(); }; struct T : public virtual S { virtual void f(); }; struct U : public virtual S, public virtual T {}; Here `T::f' is the final overrider for `S::f'. */ if (strictly_overrides (method, ffod->overriding_fn)) { ffod->overriding_fn = method; ffod->overriding_base = TREE_VALUE (path); } else if (!strictly_overrides (ffod->overriding_fn, method)) { cp_error ("no unique final overrider for `%D' in `%T'", ffod->most_derived_type, ffod->fn); cp_error ("candidates are: `%#D'", ffod->overriding_fn); cp_error (" `%#D'", method); return error_mark_node; } } else if (ffod->overriding_base && (!tree_int_cst_equal (BINFO_OFFSET (TREE_VALUE (path)), BINFO_OFFSET (ffod->overriding_base)))) { /* We've found two instances of the same base that provide overriders. */ cp_error ("no unique final overrider for `%D' since there two instances of `%T' in `%T'", ffod->fn, BINFO_TYPE (ffod->overriding_base), ffod->most_derived_type); return error_mark_node; } else { ffod->overriding_fn = method; ffod->overriding_base = TREE_VALUE (path); } } } return NULL_TREE; } /* Returns a TREE_LIST whose TREE_PURPOSE is the final overrider for FN and whose TREE_VALUE is the binfo for the base where the overriding occurs. BINFO (in the hierarchy dominated by T) is the base object in which FN is declared. */ static tree find_final_overrider (t, binfo, fn) tree t; tree binfo; tree fn; { find_final_overrider_data ffod; /* Getting this right is a little tricky. This is legal: struct S { virtual void f (); }; struct T { virtual void f (); }; struct U : public S, public T { }; even though calling `f' in `U' is ambiguous. But, struct R { virtual void f(); }; struct S : virtual public R { virtual void f (); }; struct T : virtual public R { virtual void f (); }; struct U : public S, public T { }; is not -- there's no way to decide whether to put `S::f' or `T::f' in the vtable for `R'. The solution is to look at all paths to BINFO. If we find different overriders along any two, then there is a problem. */ ffod.fn = fn; ffod.declaring_base = binfo; ffod.most_derived_type = t; ffod.overriding_fn = NULL_TREE; ffod.overriding_base = NULL_TREE; if (dfs_walk (TYPE_BINFO (t), dfs_find_final_overrider, NULL, &ffod)) return error_mark_node; return build_tree_list (ffod.overriding_fn, ffod.overriding_base); } /* Update a entry in the vtable for BINFO, which is in the hierarchy dominated by T. FN has been overridden in BINFO; VIRTUALS points to the corresponding position in the BINFO_VIRTUALS list. */ static void update_vtable_entry_for_fn (t, binfo, fn, virtuals) tree t; tree binfo; tree fn; tree *virtuals; { tree b; tree overrider; tree delta; tree virtual_base; int generate_thunk_with_vtable_p; /* Find the function which originally caused this vtable entry to be present. */ b = binfo; while (1) { tree primary_base; tree f; primary_base = get_primary_binfo (b); if (!primary_base) break; for (f = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (primary_base))); f; f = TREE_CHAIN (f)) if (same_signature_p (BV_FN (f), fn)) break; if (!f) break; fn = BV_FN (f); b = primary_base; } /* Find the final overrider. */ overrider = find_final_overrider (t, b, fn); if (overrider == error_mark_node) return; /* Compute the constant adjustment to the `this' pointer. The `this' pointer, when this function is called, will point at the class whose vtable this is. */ delta = size_binop (PLUS_EXPR, get_derived_offset (binfo, DECL_VIRTUAL_CONTEXT (fn)), BINFO_OFFSET (binfo)); /* Assume that we will produce a thunk that convert all the way to the final overrider, and not to an intermediate virtual base. */ virtual_base = NULL_TREE; /* Assume that we will always generate thunks with the vtables that reference them. */ generate_thunk_with_vtable_p = 1; /* Under the new ABI, we will convert to an intermediate virtual base first, and then use the vcall offset located there to finish the conversion. */ if (flag_new_abi) { while (b) { /* If we find BINFO, then the final overrider is in a class derived from BINFO, so the thunks can be generated with the final overrider. */ if (!virtual_base && same_type_p (BINFO_TYPE (b), BINFO_TYPE (binfo))) generate_thunk_with_vtable_p = 0; /* If we find the final overrider, then we can stop walking. */ if (same_type_p (BINFO_TYPE (b), BINFO_TYPE (TREE_VALUE (overrider)))) break; /* If we find a virtual base, and we haven't yet found the overrider, then there is a virtual base between the declaring base and the final overrider. */ if (!virtual_base && TREE_VIA_VIRTUAL (b)) { generate_thunk_with_vtable_p = 1; virtual_base = b; } b = BINFO_INHERITANCE_CHAIN (b); } } else virtual_base = NULL_TREE; if (virtual_base) /* The `this' pointer needs to be adjusted to the nearest virtual base. */ delta = size_diffop (BINFO_OFFSET (virtual_base), delta); else /* The `this' pointer needs to be adjusted from pointing to BINFO to pointing at the base where the final overrider appears. */ delta = size_diffop (BINFO_OFFSET (TREE_VALUE (overrider)), delta); modify_vtable_entry (t, binfo, TREE_PURPOSE (overrider), delta, virtuals); if (virtual_base) BV_USE_VCALL_INDEX_P (*virtuals) = 1; if (generate_thunk_with_vtable_p) BV_GENERATE_THUNK_WITH_VTABLE_P (*virtuals) = 1; } /* Called from modify_all_vtables via dfs_walk. */ static tree dfs_modify_vtables (binfo, data) tree binfo; void *data; { if (/* There's no need to modify the vtable for a primary base; we're not going to use that vtable anyhow. */ !BINFO_PRIMARY_MARKED_P (binfo) /* Similarly, a base without a vtable needs no modification. */ && CLASSTYPE_VFIELDS (BINFO_TYPE (binfo))) { tree t; tree virtuals; tree old_virtuals; t = (tree) data; /* If we're supporting RTTI then we always need a new vtable to point to the RTTI information. Under the new ABI we may need a new vtable to contain vcall and vbase offsets. */ if (flag_rtti || flag_new_abi) make_new_vtable (t, binfo); /* Now, go through each of the virtual functions in the virtual function table for BINFO. Find the final overrider, and update the BINFO_VIRTUALS list appropriately. */ for (virtuals = BINFO_VIRTUALS (binfo), old_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo))); virtuals; virtuals = TREE_CHAIN (virtuals), old_virtuals = TREE_CHAIN (old_virtuals)) update_vtable_entry_for_fn (t, binfo, BV_FN (old_virtuals), &virtuals); } SET_BINFO_MARKED (binfo); return NULL_TREE; } /* Update all of the primary and secondary vtables for T. Create new vtables as required, and initialize their RTTI information. Each of the functions in OVERRIDDEN_VIRTUALS overrides a virtual function from a base class; find and modify the appropriate entries to point to the overriding functions. Returns a list, in declaration order, of the functions that are overridden in this class, but do not appear in the primary base class vtable, and which should therefore be appended to the end of the vtable for T. */ static tree modify_all_vtables (t, vfuns_p, overridden_virtuals) tree t; int *vfuns_p; tree overridden_virtuals; { tree binfo; binfo = TYPE_BINFO (t); /* Update all of the vtables. */ dfs_walk (binfo, dfs_modify_vtables, dfs_unmarked_real_bases_queue_p, t); dfs_walk (binfo, dfs_unmark, dfs_marked_real_bases_queue_p, t); /* If we should include overriding functions for secondary vtables in our primary vtable, add them now. */ if (all_overridden_vfuns_in_vtables_p ()) { tree *fnsp = &overridden_virtuals; while (*fnsp) { tree fn = TREE_VALUE (*fnsp); if (!BINFO_VIRTUALS (binfo) || !value_member (fn, BINFO_VIRTUALS (binfo))) { /* Set the vtable index. */ set_vindex (t, fn, vfuns_p); /* We don't need to convert to a base class when calling this function. */ DECL_VIRTUAL_CONTEXT (fn) = t; /* We don't need to adjust the `this' pointer when calling this function. */ BV_DELTA (*fnsp) = integer_zero_node; BV_VCALL_INDEX (*fnsp) = NULL_TREE; /* This is an overridden function not already in our vtable. Keep it. */ fnsp = &TREE_CHAIN (*fnsp); } else /* We've already got an entry for this function. Skip it. */ *fnsp = TREE_CHAIN (*fnsp); } } else overridden_virtuals = NULL_TREE; return overridden_virtuals; } /* Here, we already know that they match in every respect. All we have to check is where they had their declarations. */ static int strictly_overrides (fndecl1, fndecl2) tree fndecl1, fndecl2; { int distance = get_base_distance (DECL_CONTEXT (fndecl2), DECL_CONTEXT (fndecl1), 0, (tree *)0); if (distance == -2 || distance > 0) return 1; return 0; } /* Get the base virtual function declarations in T that are either overridden or hidden by FNDECL as a list. We set TREE_PURPOSE with the overrider/hider. */ static tree get_basefndecls (fndecl, t) tree fndecl, t; { tree methods = TYPE_METHODS (t); tree base_fndecls = NULL_TREE; tree binfos = BINFO_BASETYPES (TYPE_BINFO (t)); int i, n_baseclasses = binfos ? TREE_VEC_LENGTH (binfos) : 0; while (methods) { if (TREE_CODE (methods) == FUNCTION_DECL && DECL_VINDEX (methods) != NULL_TREE && DECL_NAME (fndecl) == DECL_NAME (methods)) base_fndecls = tree_cons (fndecl, methods, base_fndecls); methods = TREE_CHAIN (methods); } if (base_fndecls) return base_fndecls; for (i = 0; i < n_baseclasses; i++) { tree base_binfo = TREE_VEC_ELT (binfos, i); tree basetype = BINFO_TYPE (base_binfo); base_fndecls = chainon (get_basefndecls (fndecl, basetype), base_fndecls); } return base_fndecls; } /* Mark the functions that have been hidden with their overriders. Since we start out with all functions already marked with a hider, no need to mark functions that are just hidden. Subroutine of warn_hidden. */ static void mark_overriders (fndecl, base_fndecls) tree fndecl, base_fndecls; { for (; base_fndecls; base_fndecls = TREE_CHAIN (base_fndecls)) if (same_signature_p (fndecl, TREE_VALUE (base_fndecls))) TREE_PURPOSE (base_fndecls) = fndecl; } /* If this declaration supersedes the declaration of a method declared virtual in the base class, then mark this field as being virtual as well. */ static void check_for_override (decl, ctype) tree decl, ctype; { tree binfos = BINFO_BASETYPES (TYPE_BINFO (ctype)); int i, n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0; int virtualp = DECL_VIRTUAL_P (decl); int found_overriden_fn = 0; for (i = 0; i < n_baselinks; i++) { tree base_binfo = TREE_VEC_ELT (binfos, i); if (TYPE_POLYMORPHIC_P (BINFO_TYPE (base_binfo))) { tree tmp = get_matching_virtual (base_binfo, decl, DECL_DESTRUCTOR_P (decl)); if (tmp && !found_overriden_fn) { /* If this function overrides some virtual in some base class, then the function itself is also necessarily virtual, even if the user didn't explicitly say so. */ DECL_VIRTUAL_P (decl) = 1; /* The TMP we really want is the one from the deepest baseclass on this path, taking care not to duplicate if we have already found it (via another path to its virtual baseclass. */ if (TREE_CODE (TREE_TYPE (decl)) == FUNCTION_TYPE) { cp_error_at ("`static %#D' cannot be declared", decl); cp_error_at (" since `virtual %#D' declared in base class", tmp); break; } virtualp = 1; /* Set DECL_VINDEX to a value that is neither an INTEGER_CST nor the error_mark_node so that add_virtual_function will realize this is an overridden function. */ DECL_VINDEX (decl) = tree_cons (tmp, NULL_TREE, DECL_VINDEX (decl)); /* We now know that DECL overrides something, which is all that is important. But, we must continue to iterate through all the base-classes in order to allow get_matching_virtual to check for various illegal overrides. */ found_overriden_fn = 1; } } } if (virtualp) { if (DECL_VINDEX (decl) == NULL_TREE) DECL_VINDEX (decl) = error_mark_node; IDENTIFIER_VIRTUAL_P (DECL_NAME (decl)) = 1; } } /* Warn about hidden virtual functions that are not overridden in t. We know that constructors and destructors don't apply. */ void warn_hidden (t) tree t; { tree method_vec = CLASSTYPE_METHOD_VEC (t); int n_methods = method_vec ? TREE_VEC_LENGTH (method_vec) : 0; int i; /* We go through each separately named virtual function. */ for (i = 2; i < n_methods && TREE_VEC_ELT (method_vec, i); ++i) { tree fns = TREE_VEC_ELT (method_vec, i); tree fndecl = NULL_TREE; tree base_fndecls = NULL_TREE; tree binfos = BINFO_BASETYPES (TYPE_BINFO (t)); int i, n_baseclasses = binfos ? TREE_VEC_LENGTH (binfos) : 0; /* First see if we have any virtual functions in this batch. */ for (; fns; fns = OVL_NEXT (fns)) { fndecl = OVL_CURRENT (fns); if (DECL_VINDEX (fndecl)) break; } if (fns == NULL_TREE) continue; /* First we get a list of all possible functions that might be hidden from each base class. */ for (i = 0; i < n_baseclasses; i++) { tree base_binfo = TREE_VEC_ELT (binfos, i); tree basetype = BINFO_TYPE (base_binfo); base_fndecls = chainon (get_basefndecls (fndecl, basetype), base_fndecls); } fns = OVL_NEXT (fns); /* ...then mark up all the base functions with overriders, preferring overriders to hiders. */ if (base_fndecls) for (; fns; fns = OVL_NEXT (fns)) { fndecl = OVL_CURRENT (fns); if (DECL_VINDEX (fndecl)) mark_overriders (fndecl, base_fndecls); } /* Now give a warning for all base functions without overriders, as they are hidden. */ for (; base_fndecls; base_fndecls = TREE_CHAIN (base_fndecls)) if (!same_signature_p (TREE_PURPOSE (base_fndecls), TREE_VALUE (base_fndecls))) { /* Here we know it is a hider, and no overrider exists. */ cp_warning_at ("`%D' was hidden", TREE_VALUE (base_fndecls)); cp_warning_at (" by `%D'", TREE_PURPOSE (base_fndecls)); } } } /* Check for things that are invalid. There are probably plenty of other things we should check for also. */ static void finish_struct_anon (t) tree t; { tree field; for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field)) { if (TREE_STATIC (field)) continue; if (TREE_CODE (field) != FIELD_DECL) continue; if (DECL_NAME (field) == NULL_TREE && ANON_AGGR_TYPE_P (TREE_TYPE (field))) { tree elt = TYPE_FIELDS (TREE_TYPE (field)); for (; elt; elt = TREE_CHAIN (elt)) { if (DECL_ARTIFICIAL (elt)) continue; if (DECL_NAME (elt) == constructor_name (t)) cp_pedwarn_at ("ISO C++ forbids member `%D' with same name as enclosing class", elt); if (TREE_CODE (elt) != FIELD_DECL) { cp_pedwarn_at ("`%#D' invalid; an anonymous union can only have non-static data members", elt); continue; } if (TREE_PRIVATE (elt)) cp_pedwarn_at ("private member `%#D' in anonymous union", elt); else if (TREE_PROTECTED (elt)) cp_pedwarn_at ("protected member `%#D' in anonymous union", elt); TREE_PRIVATE (elt) = TREE_PRIVATE (field); TREE_PROTECTED (elt) = TREE_PROTECTED (field); } } } } /* Create default constructors, assignment operators, and so forth for the type indicated by T, if they are needed. CANT_HAVE_DEFAULT_CTOR, CANT_HAVE_CONST_CTOR, and CANT_HAVE_CONST_ASSIGNMENT are nonzero if, for whatever reason, the class cannot have a default constructor, copy constructor taking a const reference argument, or an assignment operator taking a const reference, respectively. If a virtual destructor is created, its DECL is returned; otherwise the return value is NULL_TREE. */ static tree add_implicitly_declared_members (t, cant_have_default_ctor, cant_have_const_cctor, cant_have_const_assignment) tree t; int cant_have_default_ctor; int cant_have_const_cctor; int cant_have_const_assignment; { tree default_fn; tree implicit_fns = NULL_TREE; tree virtual_dtor = NULL_TREE; tree *f; /* Destructor. */ if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) && !TYPE_HAS_DESTRUCTOR (t)) { default_fn = implicitly_declare_fn (sfk_destructor, t, /*const_p=*/0); check_for_override (default_fn, t); /* If we couldn't make it work, then pretend we didn't need it. */ if (default_fn == void_type_node) TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = 0; else { TREE_CHAIN (default_fn) = implicit_fns; implicit_fns = default_fn; if (DECL_VINDEX (default_fn)) virtual_dtor = default_fn; } } else /* Any non-implicit destructor is non-trivial. */ TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) |= TYPE_HAS_DESTRUCTOR (t); /* Default constructor. */ if (! TYPE_HAS_CONSTRUCTOR (t) && ! cant_have_default_ctor) { default_fn = implicitly_declare_fn (sfk_constructor, t, /*const_p=*/0); TREE_CHAIN (default_fn) = implicit_fns; implicit_fns = default_fn; } /* Copy constructor. */ if (! TYPE_HAS_INIT_REF (t) && ! TYPE_FOR_JAVA (t)) { /* ARM 12.18: You get either X(X&) or X(const X&), but not both. --Chip */ default_fn = implicitly_declare_fn (sfk_copy_constructor, t, /*const_p=*/!cant_have_const_cctor); TREE_CHAIN (default_fn) = implicit_fns; implicit_fns = default_fn; } /* Assignment operator. */ if (! TYPE_HAS_ASSIGN_REF (t) && ! TYPE_FOR_JAVA (t)) { default_fn = implicitly_declare_fn (sfk_assignment_operator, t, /*const_p=*/!cant_have_const_assignment); TREE_CHAIN (default_fn) = implicit_fns; implicit_fns = default_fn; } /* Now, hook all of the new functions on to TYPE_METHODS, and add them to the CLASSTYPE_METHOD_VEC. */ for (f = &implicit_fns; *f; f = &TREE_CHAIN (*f)) add_method (t, *f, /*error_p=*/0); *f = TYPE_METHODS (t); TYPE_METHODS (t) = implicit_fns; return virtual_dtor; } /* Subroutine of finish_struct_1. Recursively count the number of fields in TYPE, including anonymous union members. */ static int count_fields (fields) tree fields; { tree x; int n_fields = 0; for (x = fields; x; x = TREE_CHAIN (x)) { if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x))) n_fields += count_fields (TYPE_FIELDS (TREE_TYPE (x))); else n_fields += 1; } return n_fields; } /* Subroutine of finish_struct_1. Recursively add all the fields in the TREE_LIST FIELDS to the TREE_VEC FIELD_VEC, starting at offset IDX. */ static int add_fields_to_vec (fields, field_vec, idx) tree fields, field_vec; int idx; { tree x; for (x = fields; x; x = TREE_CHAIN (x)) { if (TREE_CODE (x) == FIELD_DECL && ANON_AGGR_TYPE_P (TREE_TYPE (x))) idx = add_fields_to_vec (TYPE_FIELDS (TREE_TYPE (x)), field_vec, idx); else TREE_VEC_ELT (field_vec, idx++) = x; } return idx; } /* FIELD is a bit-field. We are finishing the processing for its enclosing type. Issue any appropriate messages and set appropriate flags. */ static void check_bitfield_decl (field) tree field; { tree type = TREE_TYPE (field); tree w = NULL_TREE; /* Detect invalid bit-field type. */ if (DECL_INITIAL (field) && ! INTEGRAL_TYPE_P (TREE_TYPE (field))) { cp_error_at ("bit-field `%#D' with non-integral type", field); w = error_mark_node; } /* Detect and ignore out of range field width. */ if (DECL_INITIAL (field)) { w = DECL_INITIAL (field); /* Avoid the non_lvalue wrapper added by fold for PLUS_EXPRs. */ STRIP_NOPS (w); /* detect invalid field size. */ if (TREE_CODE (w) == CONST_DECL) w = DECL_INITIAL (w); else w = decl_constant_value (w); if (TREE_CODE (w) != INTEGER_CST) { cp_error_at ("bit-field `%D' width not an integer constant", field); w = error_mark_node; } else if (tree_int_cst_sgn (w) < 0) { cp_error_at ("negative width in bit-field `%D'", field); w = error_mark_node; } else if (integer_zerop (w) && DECL_NAME (field) != 0) { cp_error_at ("zero width for bit-field `%D'", field); w = error_mark_node; } else if (compare_tree_int (w, TYPE_PRECISION (type)) > 0 && TREE_CODE (type) != ENUMERAL_TYPE && TREE_CODE (type) != BOOLEAN_TYPE) cp_warning_at ("width of `%D' exceeds its type", field); else if (TREE_CODE (type) == ENUMERAL_TYPE && (0 > compare_tree_int (w, min_precision (TYPE_MIN_VALUE (type), TREE_UNSIGNED (type))) || 0 > compare_tree_int (w, min_precision (TYPE_MAX_VALUE (type), TREE_UNSIGNED (type))))) cp_warning_at ("`%D' is too small to hold all values of `%#T'", field, type); } /* Remove the bit-field width indicator so that the rest of the compiler does not treat that value as an initializer. */ DECL_INITIAL (field) = NULL_TREE; if (w != error_mark_node) { DECL_SIZE (field) = convert (bitsizetype, w); DECL_BIT_FIELD (field) = 1; if (integer_zerop (w)) { #ifdef EMPTY_FIELD_BOUNDARY DECL_ALIGN (field) = MAX (DECL_ALIGN (field), EMPTY_FIELD_BOUNDARY); #endif #ifdef PCC_BITFIELD_TYPE_MATTERS if (PCC_BITFIELD_TYPE_MATTERS) { DECL_ALIGN (field) = MAX (DECL_ALIGN (field), TYPE_ALIGN (type)); DECL_USER_ALIGN (field) |= TYPE_USER_ALIGN (type); } #endif } } else { /* Non-bit-fields are aligned for their type. */ DECL_BIT_FIELD (field) = 0; CLEAR_DECL_C_BIT_FIELD (field); DECL_ALIGN (field) = MAX (DECL_ALIGN (field), TYPE_ALIGN (type)); DECL_USER_ALIGN (field) |= TYPE_USER_ALIGN (type); } } /* FIELD is a non bit-field. We are finishing the processing for its enclosing type T. Issue any appropriate messages and set appropriate flags. */ static void check_field_decl (field, t, cant_have_const_ctor, cant_have_default_ctor, no_const_asn_ref, any_default_members) tree field; tree t; int *cant_have_const_ctor; int *cant_have_default_ctor; int *no_const_asn_ref; int *any_default_members; { tree type = strip_array_types (TREE_TYPE (field)); /* An anonymous union cannot contain any fields which would change the settings of CANT_HAVE_CONST_CTOR and friends. */ if (ANON_UNION_TYPE_P (type)) ; /* And, we don't set TYPE_HAS_CONST_INIT_REF, etc., for anonymous structs. So, we recurse through their fields here. */ else if (ANON_AGGR_TYPE_P (type)) { tree fields; for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields)) if (TREE_CODE (fields) == FIELD_DECL && !DECL_C_BIT_FIELD (field)) check_field_decl (fields, t, cant_have_const_ctor, cant_have_default_ctor, no_const_asn_ref, any_default_members); } /* Check members with class type for constructors, destructors, etc. */ else if (CLASS_TYPE_P (type)) { /* Never let anything with uninheritable virtuals make it through without complaint. */ abstract_virtuals_error (field, type); if (TREE_CODE (t) == UNION_TYPE) { if (TYPE_NEEDS_CONSTRUCTING (type)) cp_error_at ("member `%#D' with constructor not allowed in union", field); if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)) cp_error_at ("member `%#D' with destructor not allowed in union", field); if (TYPE_HAS_COMPLEX_ASSIGN_REF (type)) cp_error_at ("member `%#D' with copy assignment operator not allowed in union", field); } else { TYPE_NEEDS_CONSTRUCTING (t) |= TYPE_NEEDS_CONSTRUCTING (type); TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) |= TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type); TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_COMPLEX_ASSIGN_REF (type); TYPE_HAS_COMPLEX_INIT_REF (t) |= TYPE_HAS_COMPLEX_INIT_REF (type); } if (!TYPE_HAS_CONST_INIT_REF (type)) *cant_have_const_ctor = 1; if (!TYPE_HAS_CONST_ASSIGN_REF (type)) *no_const_asn_ref = 1; if (TYPE_HAS_CONSTRUCTOR (type) && ! TYPE_HAS_DEFAULT_CONSTRUCTOR (type)) *cant_have_default_ctor = 1; } if (DECL_INITIAL (field) != NULL_TREE) { /* `build_class_init_list' does not recognize non-FIELD_DECLs. */ if (TREE_CODE (t) == UNION_TYPE && any_default_members != 0) cp_error_at ("multiple fields in union `%T' initialized"); *any_default_members = 1; } /* Non-bit-fields are aligned for their type, except packed fields which require only BITS_PER_UNIT alignment. */ DECL_ALIGN (field) = MAX (DECL_ALIGN (field), (DECL_PACKED (field) ? BITS_PER_UNIT : TYPE_ALIGN (TREE_TYPE (field)))); if (! DECL_PACKED (field)) DECL_USER_ALIGN (field) |= TYPE_USER_ALIGN (TREE_TYPE (field)); } /* Check the data members (both static and non-static), class-scoped typedefs, etc., appearing in the declaration of T. Issue appropriate diagnostics. Sets ACCESS_DECLS to a list (in declaration order) of access declarations; each TREE_VALUE in this list is a USING_DECL. In addition, set the following flags: EMPTY_P The class is empty, i.e., contains no non-static data members. CANT_HAVE_DEFAULT_CTOR_P This class cannot have an implicitly generated default constructor. CANT_HAVE_CONST_CTOR_P This class cannot have an implicitly generated copy constructor taking a const reference. CANT_HAVE_CONST_ASN_REF This class cannot have an implicitly generated assignment operator taking a const reference. All of these flags should be initialized before calling this function. Returns a pointer to the end of the TYPE_FIELDs chain; additional fields can be added by adding to this chain. */ static void check_field_decls (t, access_decls, empty_p, cant_have_default_ctor_p, cant_have_const_ctor_p, no_const_asn_ref_p) tree t; tree *access_decls; int *empty_p; int *cant_have_default_ctor_p; int *cant_have_const_ctor_p; int *no_const_asn_ref_p; { tree *field; tree *next; int has_pointers; int any_default_members; /* First, delete any duplicate fields. */ delete_duplicate_fields (TYPE_FIELDS (t)); /* Assume there are no access declarations. */ *access_decls = NULL_TREE; /* Assume this class has no pointer members. */ has_pointers = 0; /* Assume none of the members of this class have default initializations. */ any_default_members = 0; for (field = &TYPE_FIELDS (t); *field; field = next) { tree x = *field; tree type = TREE_TYPE (x); GNU_xref_member (current_class_name, x); next = &TREE_CHAIN (x); if (TREE_CODE (x) == FIELD_DECL) { DECL_PACKED (x) |= TYPE_PACKED (t); if (DECL_C_BIT_FIELD (x) && integer_zerop (DECL_INITIAL (x))) /* We don't treat zero-width bitfields as making a class non-empty. */ ; else { /* The class is non-empty. */ *empty_p = 0; /* The class is not even nearly empty. */ CLASSTYPE_NEARLY_EMPTY_P (t) = 0; } } if (TREE_CODE (x) == USING_DECL) { /* Prune the access declaration from the list of fields. */ *field = TREE_CHAIN (x); /* Save the access declarations for our caller. */ *access_decls = tree_cons (NULL_TREE, x, *access_decls); /* Since we've reset *FIELD there's no reason to skip to the next field. */ next = field; continue; } if (TREE_CODE (x) == TYPE_DECL || TREE_CODE (x) == TEMPLATE_DECL) continue; /* If we've gotten this far, it's a data member, possibly static, or an enumerator. */ DECL_CONTEXT (x) = t; /* ``A local class cannot have static data members.'' ARM 9.4 */ if (current_function_decl && TREE_STATIC (x)) cp_error_at ("field `%D' in local class cannot be static", x); /* Perform error checking that did not get done in grokdeclarator. */ if (TREE_CODE (type) == FUNCTION_TYPE) { cp_error_at ("field `%D' invalidly declared function type", x); type = build_pointer_type (type); TREE_TYPE (x) = type; } else if (TREE_CODE (type) == METHOD_TYPE) { cp_error_at ("field `%D' invalidly declared method type", x); type = build_pointer_type (type); TREE_TYPE (x) = type; } else if (TREE_CODE (type) == OFFSET_TYPE) { cp_error_at ("field `%D' invalidly declared offset type", x); type = build_pointer_type (type); TREE_TYPE (x) = type; } if (type == error_mark_node) continue; /* When this goes into scope, it will be a non-local reference. */ DECL_NONLOCAL (x) = 1; if (TREE_CODE (x) == CONST_DECL) continue; if (TREE_CODE (x) == VAR_DECL) { if (TREE_CODE (t) == UNION_TYPE) /* Unions cannot have static members. */ cp_error_at ("field `%D' declared static in union", x); continue; } /* Now it can only be a FIELD_DECL. */ if (TREE_PRIVATE (x) || TREE_PROTECTED (x)) CLASSTYPE_NON_AGGREGATE (t) = 1; /* If this is of reference type, check if it needs an init. Also do a little ANSI jig if necessary. */ if (TREE_CODE (type) == REFERENCE_TYPE) { CLASSTYPE_NON_POD_P (t) = 1; if (DECL_INITIAL (x) == NULL_TREE) CLASSTYPE_REF_FIELDS_NEED_INIT (t) = 1; /* ARM $12.6.2: [A member initializer list] (or, for an aggregate, initialization by a brace-enclosed list) is the only way to initialize nonstatic const and reference members. */ *cant_have_default_ctor_p = 1; TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1; if (! TYPE_HAS_CONSTRUCTOR (t) && extra_warnings) { if (DECL_NAME (x)) cp_warning_at ("non-static reference `%#D' in class without a constructor", x); else cp_warning_at ("non-static reference in class without a constructor", x); } } type = strip_array_types (type); if (TREE_CODE (type) == POINTER_TYPE) has_pointers = 1; if (DECL_MUTABLE_P (x) || TYPE_HAS_MUTABLE_P (type)) CLASSTYPE_HAS_MUTABLE (t) = 1; if (! pod_type_p (type) /* For some reason, pointers to members are POD types themselves, but are not allowed in POD structs. Silly. */ || TYPE_PTRMEM_P (type) || TYPE_PTRMEMFUNC_P (type)) CLASSTYPE_NON_POD_P (t) = 1; /* If any field is const, the structure type is pseudo-const. */ if (CP_TYPE_CONST_P (type)) { C_TYPE_FIELDS_READONLY (t) = 1; if (DECL_INITIAL (x) == NULL_TREE) CLASSTYPE_READONLY_FIELDS_NEED_INIT (t) = 1; /* ARM $12.6.2: [A member initializer list] (or, for an aggregate, initialization by a brace-enclosed list) is the only way to initialize nonstatic const and reference members. */ *cant_have_default_ctor_p = 1; TYPE_HAS_COMPLEX_ASSIGN_REF (t) = 1; if (! TYPE_HAS_CONSTRUCTOR (t) && extra_warnings) { if (DECL_NAME (x)) cp_warning_at ("non-static const member `%#D' in class without a constructor", x); else cp_warning_at ("non-static const member in class without a constructor", x); } } /* A field that is pseudo-const makes the structure likewise. */ else if (IS_AGGR_TYPE (type)) { C_TYPE_FIELDS_READONLY (t) |= C_TYPE_FIELDS_READONLY (type); CLASSTYPE_READONLY_FIELDS_NEED_INIT (t) |= CLASSTYPE_READONLY_FIELDS_NEED_INIT (type); } /* Core issue 80: A nonstatic data member is required to have a different name from the class iff the class has a user-defined constructor. */ if (DECL_NAME (x) == constructor_name (t) && TYPE_HAS_CONSTRUCTOR (t)) cp_pedwarn_at ("field `%#D' with same name as class", x); /* We set DECL_C_BIT_FIELD in grokbitfield. If the type and width are valid, we'll also set DECL_BIT_FIELD. */ if (DECL_C_BIT_FIELD (x)) check_bitfield_decl (x); else check_field_decl (x, t, cant_have_const_ctor_p, cant_have_default_ctor_p, no_const_asn_ref_p, &any_default_members); } /* Effective C++ rule 11. */ if (has_pointers && warn_ecpp && TYPE_HAS_CONSTRUCTOR (t) && ! (TYPE_HAS_INIT_REF (t) && TYPE_HAS_ASSIGN_REF (t))) { cp_warning ("`%#T' has pointer data members", t); if (! TYPE_HAS_INIT_REF (t)) { cp_warning (" but does not override `%T(const %T&)'", t, t); if (! TYPE_HAS_ASSIGN_REF (t)) cp_warning (" or `operator=(const %T&)'", t); } else if (! TYPE_HAS_ASSIGN_REF (t)) cp_warning (" but does not override `operator=(const %T&)'", t); } /* Check anonymous struct/anonymous union fields. */ finish_struct_anon (t); /* We've built up the list of access declarations in reverse order. Fix that now. */ *access_decls = nreverse (*access_decls); } /* Return a FIELD_DECL for a pointer-to-virtual-table or pointer-to-virtual-base. The NAME, ASSEMBLER_NAME, and TYPE of the field are as indicated. The CLASS_TYPE in which this field occurs is also indicated. FCONTEXT is the type that is needed for the debug info output routines. *EMPTY_P is set to a non-zero value by this function to indicate that a class containing this field is non-empty. */ static tree build_vtbl_or_vbase_field (name, assembler_name, type, class_type, fcontext, empty_p) tree name; tree assembler_name; tree type; tree class_type; tree fcontext; int *empty_p; { tree field; /* This class is non-empty. */ *empty_p = 0; /* Build the FIELD_DECL. */ field = build_decl (FIELD_DECL, name, type); DECL_ASSEMBLER_NAME (field) = assembler_name; DECL_VIRTUAL_P (field) = 1; DECL_ARTIFICIAL (field) = 1; DECL_FIELD_CONTEXT (field) = class_type; DECL_FCONTEXT (field) = fcontext; DECL_ALIGN (field) = TYPE_ALIGN (type); DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (type); /* Return it. */ return field; } /* If TYPE is an empty class type, records its OFFSET in the table of OFFSETS. */ static int record_subobject_offset (type, offset, offsets) tree type; tree offset; splay_tree offsets; { splay_tree_node n; if (!is_empty_class (type)) return 0; /* Record the location of this empty object in OFFSETS. */ n = splay_tree_lookup (offsets, (splay_tree_key) offset); if (!n) n = splay_tree_insert (offsets, (splay_tree_key) offset, (splay_tree_value) NULL_TREE); n->value = ((splay_tree_value) tree_cons (NULL_TREE, type, (tree) n->value)); return 0; } /* Returns non-zero if TYPE is an empty class type and there is already an entry in OFFSETS for the same TYPE as the same OFFSET. */ static int check_subobject_offset (type, offset, offsets) tree type; tree offset; splay_tree offsets; { splay_tree_node n; tree t; if (!is_empty_class (type)) return 0; /* Record the location of this empty object in OFFSETS. */ n = splay_tree_lookup (offsets, (splay_tree_key) offset); if (!n) return 0; for (t = (tree) n->value; t; t = TREE_CHAIN (t)) if (same_type_p (TREE_VALUE (t), type)) return 1; return 0; } /* Walk through all the subobjects of TYPE (located at OFFSET). Call F for every subobject, passing it the type, offset, and table of OFFSETS. If VBASES_P is non-zero, then even non-virtual primary bases should be traversed; otherwise, they are ignored. If F returns a non-zero value, the traversal ceases, and that value is returned. Otherwise, returns zero. */ static int walk_subobject_offsets (type, f, offset, offsets, vbases_p) tree type; subobject_offset_fn f; tree offset; splay_tree offsets; int vbases_p; { int r = 0; if (CLASS_TYPE_P (type)) { tree field; int i; /* Record the location of TYPE. */ r = (*f) (type, offset, offsets); if (r) return r; /* Iterate through the direct base classes of TYPE. */ for (i = 0; i < CLASSTYPE_N_BASECLASSES (type); ++i) { tree binfo = BINFO_BASETYPE (TYPE_BINFO (type), i); if (!vbases_p && TREE_VIA_VIRTUAL (binfo) && !BINFO_PRIMARY_MARKED_P (binfo)) continue; r = walk_subobject_offsets (BINFO_TYPE (binfo), f, size_binop (PLUS_EXPR, offset, BINFO_OFFSET (binfo)), offsets, vbases_p); if (r) return r; } /* Iterate through the fields of TYPE. */ for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) if (TREE_CODE (field) == FIELD_DECL) { r = walk_subobject_offsets (TREE_TYPE (field), f, size_binop (PLUS_EXPR, offset, DECL_FIELD_OFFSET (field)), offsets, /*vbases_p=*/1); if (r) return r; } } else if (TREE_CODE (type) == ARRAY_TYPE) { tree domain = TYPE_DOMAIN (type); tree index; /* Step through each of the elements in the array. */ for (index = size_zero_node; INT_CST_LT (index, TYPE_MAX_VALUE (domain)); index = size_binop (PLUS_EXPR, index, size_one_node)) { r = walk_subobject_offsets (TREE_TYPE (type), f, offset, offsets, /*vbases_p=*/1); if (r) return r; offset = size_binop (PLUS_EXPR, offset, TYPE_SIZE_UNIT (TREE_TYPE (type))); } } return 0; } /* Record all of the empty subobjects of TYPE (located at OFFSET) in OFFSETS. If VBASES_P is non-zero, virtual bases of TYPE are examined. */ static void record_subobject_offsets (type, offset, offsets, vbases_p) tree type; tree offset; splay_tree offsets; int vbases_p; { walk_subobject_offsets (type, record_subobject_offset, offset, offsets, vbases_p); } /* Returns non-zero if any of the empty subobjects of TYPE (located at OFFSET) conflict with entries in OFFSETS. If VBASES_P is non-zero, virtual bases of TYPE are examined. */ static int layout_conflict_p (type, offset, offsets, vbases_p) tree type; tree offset; splay_tree offsets; int vbases_p; { return walk_subobject_offsets (type, check_subobject_offset, offset, offsets, vbases_p); } /* DECL is a FIELD_DECL corresponding either to a base subobject of a non-static data member of the type indicated by RLI. BINFO is the binfo corresponding to the base subobject, OFFSETS maps offsets to types already located at those offsets. This function determines the position of the DECL. */ static void layout_nonempty_base_or_field (rli, decl, binfo, offsets) record_layout_info rli; tree decl; tree binfo; splay_tree offsets; { tree offset = NULL_TREE; tree type = TREE_TYPE (decl); /* If we are laying out a base class, rather than a field, then DECL_ARTIFICIAL will be set on the FIELD_DECL. */ int field_p = !DECL_ARTIFICIAL (decl); /* Try to place the field. It may take more than one try if we have a hard time placing the field without putting two objects of the same type at the same address. */ while (1) { struct record_layout_info_s old_rli = *rli; /* Place this field. */ place_field (rli, decl); offset = byte_position (decl); /* We have to check to see whether or not there is already something of the same type at the offset we're about to use. For example: struct S {}; struct T : public S { int i; }; struct U : public S, public T {}; Here, we put S at offset zero in U. Then, we can't put T at offset zero -- its S component would be at the same address as the S we already allocated. So, we have to skip ahead. Since all data members, including those whose type is an empty class, have non-zero size, any overlap can happen only with a direct or indirect base-class -- it can't happen with a data member. */ if (flag_new_abi && layout_conflict_p (TREE_TYPE (decl), offset, offsets, field_p)) { /* Strip off the size allocated to this field. That puts us at the first place we could have put the field with proper alignment. */ *rli = old_rli; /* Bump up by the alignment required for the type. */ rli->bitpos = size_binop (PLUS_EXPR, rli->bitpos, bitsize_int (binfo ? CLASSTYPE_ALIGN (type) : TYPE_ALIGN (type))); normalize_rli (rli); } else /* There was no conflict. We're done laying out this field. */ break; } /* Now that we know where it wil be placed, update its BINFO_OFFSET. */ if (binfo && CLASS_TYPE_P (BINFO_TYPE (binfo))) propagate_binfo_offsets (binfo, convert (ssizetype, offset)); } /* Layout the empty base BINFO. EOC indicates the byte currently just past the end of the class, and should be correctly aligned for a class of the type indicated by BINFO; OFFSETS gives the offsets of the empty bases allocated so far. */ static void layout_empty_base (binfo, eoc, offsets) tree binfo; tree eoc; splay_tree offsets; { tree alignment; tree basetype = BINFO_TYPE (binfo); /* This routine should only be used for empty classes. */ my_friendly_assert (is_empty_class (basetype), 20000321); alignment = ssize_int (CLASSTYPE_ALIGN_UNIT (basetype)); /* This is an empty base class. We first try to put it at offset zero. */ if (layout_conflict_p (BINFO_TYPE (binfo), BINFO_OFFSET (binfo), offsets, /*vbases_p=*/0)) { /* That didn't work. Now, we move forward from the next available spot in the class. */ propagate_binfo_offsets (binfo, convert (ssizetype, eoc)); while (1) { if (!layout_conflict_p (BINFO_TYPE (binfo), BINFO_OFFSET (binfo), offsets, /*vbases_p=*/0)) /* We finally found a spot where there's no overlap. */ break; /* There's overlap here, too. Bump along to the next spot. */ propagate_binfo_offsets (binfo, alignment); } } } /* Build a FIELD_DECL for the base given by BINFO in the class indicated by RLI. If the new object is non-empty, clear *EMPTY_P. *BASE_ALIGN is a running maximum of the alignments of any base class. OFFSETS gives the location of empty base subobjects. */ static void build_base_field (rli, binfo, empty_p, base_align, offsets) record_layout_info rli; tree binfo; int *empty_p; unsigned int *base_align; splay_tree offsets; { tree basetype = BINFO_TYPE (binfo); tree decl; if (!COMPLETE_TYPE_P (basetype)) /* This error is now reported in xref_tag, thus giving better location information. */ return; decl = build_decl (FIELD_DECL, NULL_TREE, basetype); DECL_ARTIFICIAL (decl) = 1; DECL_FIELD_CONTEXT (decl) = rli->t; DECL_SIZE (decl) = CLASSTYPE_SIZE (basetype); DECL_SIZE_UNIT (decl) = CLASSTYPE_SIZE_UNIT (basetype); DECL_ALIGN (decl) = CLASSTYPE_ALIGN (basetype); DECL_USER_ALIGN (decl) = CLASSTYPE_USER_ALIGN (basetype); if (! flag_new_abi) { /* Brain damage for backwards compatibility. For no good reason, the old basetype layout made every base have at least as large as the alignment for the bases up to that point, gratuitously wasting space. So we do the same thing here. */ *base_align = MAX (*base_align, DECL_ALIGN (decl)); DECL_SIZE (decl) = size_binop (MAX_EXPR, DECL_SIZE (decl), bitsize_int (*base_align)); DECL_SIZE_UNIT (decl) = size_binop (MAX_EXPR, DECL_SIZE_UNIT (decl), size_int (*base_align / BITS_PER_UNIT)); } if (!integer_zerop (DECL_SIZE (decl))) { /* The containing class is non-empty because it has a non-empty base class. */ *empty_p = 0; /* Try to place the field. It may take more than one try if we have a hard time placing the field without putting two objects of the same type at the same address. */ layout_nonempty_base_or_field (rli, decl, binfo, offsets); } else { unsigned HOST_WIDE_INT eoc; /* On some platforms (ARM), even empty classes will not be byte-aligned. */ eoc = tree_low_cst (rli_size_unit_so_far (rli), 0); eoc = CEIL (eoc, DECL_ALIGN_UNIT (decl)) * DECL_ALIGN_UNIT (decl); layout_empty_base (binfo, size_int (eoc), offsets); } /* Check for inaccessible base classes. If the same base class appears more than once in the hierarchy, but isn't virtual, then it's ambiguous. */ if (get_base_distance (basetype, rli->t, 0, NULL) == -2) cp_warning ("direct base `%T' inaccessible in `%T' due to ambiguity", basetype, rli->t); /* Record the offsets of BINFO and its base subobjects. */ record_subobject_offsets (BINFO_TYPE (binfo), BINFO_OFFSET (binfo), offsets, /*vbases_p=*/0); } /* Layout all of the non-virtual base classes. Record empty subobjects in OFFSETS. */ static void build_base_fields (rli, empty_p, offsets) record_layout_info rli; int *empty_p; splay_tree offsets; { /* Chain to hold all the new FIELD_DECLs which stand in for base class subobjects. */ tree rec = rli->t; int n_baseclasses = CLASSTYPE_N_BASECLASSES (rec); int i; unsigned int base_align = 0; /* Under the new ABI, the primary base class is always allocated first. */ if (flag_new_abi && CLASSTYPE_HAS_PRIMARY_BASE_P (rec)) build_base_field (rli, CLASSTYPE_PRIMARY_BINFO (rec), empty_p, &base_align, offsets); /* Now allocate the rest of the bases. */ for (i = 0; i < n_baseclasses; ++i) { tree base_binfo; base_binfo = BINFO_BASETYPE (TYPE_BINFO (rec), i); /* Under the new ABI, the primary base was already allocated above, so we don't need to allocate it again here. */ if (flag_new_abi && base_binfo == CLASSTYPE_PRIMARY_BINFO (rec)) continue; /* A primary virtual base class is allocated just like any other base class, but a non-primary virtual base is allocated later, in layout_virtual_bases. */ if (TREE_VIA_VIRTUAL (base_binfo) && !BINFO_PRIMARY_MARKED_P (base_binfo)) continue; build_base_field (rli, base_binfo, empty_p, &base_align, offsets); } } /* Go through the TYPE_METHODS of T issuing any appropriate diagnostics, figuring out which methods override which other methods, and so forth. */ static void check_methods (t) tree t; { tree x; int seen_one_arg_array_delete_p = 0; for (x = TYPE_METHODS (t); x; x = TREE_CHAIN (x)) { GNU_xref_member (current_class_name, x); /* If this was an evil function, don't keep it in class. */ if (IDENTIFIER_ERROR_LOCUS (DECL_ASSEMBLER_NAME (x))) continue; check_for_override (x, t); if (DECL_PURE_VIRTUAL_P (x) && ! DECL_VINDEX (x)) cp_error_at ("initializer specified for non-virtual method `%D'", x); /* The name of the field is the original field name Save this in auxiliary field for later overloading. */ if (DECL_VINDEX (x)) { TYPE_POLYMORPHIC_P (t) = 1; if (DECL_PURE_VIRTUAL_P (x)) CLASSTYPE_PURE_VIRTUALS (t) = tree_cons (NULL_TREE, x, CLASSTYPE_PURE_VIRTUALS (t)); } if (DECL_ARRAY_DELETE_OPERATOR_P (x)) { tree second_parm; /* When dynamically allocating an array of this type, we need a "cookie" to record how many elements we allocated, even if the array elements have no non-trivial destructor, if the usual array deallocation function takes a second argument of type size_t. The standard (in [class.free]) requires that the second argument be set correctly. */ second_parm = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (x))); /* This is overly conservative, but we must maintain this behavior for backwards compatibility. */ if (!flag_new_abi && second_parm != void_list_node) TYPE_VEC_DELETE_TAKES_SIZE (t) = 1; /* Under the new ABI, we choose only those function that are explicitly declared as `operator delete[] (void *, size_t)'. */ else if (flag_new_abi && !seen_one_arg_array_delete_p && second_parm && TREE_CHAIN (second_parm) == void_list_node && same_type_p (TREE_VALUE (second_parm), sizetype)) TYPE_VEC_DELETE_TAKES_SIZE (t) = 1; /* If there's no second parameter, then this is the usual deallocation function. */ else if (second_parm == void_list_node) seen_one_arg_array_delete_p = 1; } } } /* FN is a constructor or destructor. Clone the declaration to create a specialized in-charge or not-in-charge version, as indicated by NAME. */ static tree build_clone (fn, name) tree fn; tree name; { tree parms; tree clone; /* Copy the function. */ clone = copy_decl (fn); /* Remember where this function came from. */ DECL_CLONED_FUNCTION (clone) = fn; /* Reset the function name. */ DECL_NAME (clone) = name; DECL_ASSEMBLER_NAME (clone) = DECL_NAME (clone); /* There's no pending inline data for this function. */ DECL_PENDING_INLINE_INFO (clone) = NULL; DECL_PENDING_INLINE_P (clone) = 0; /* And it hasn't yet been deferred. */ DECL_DEFERRED_FN (clone) = 0; /* There's no magic VTT parameter in the clone. */ DECL_VTT_PARM (clone) = NULL_TREE; /* The base-class destructor is not virtual. */ if (name == base_dtor_identifier) { DECL_VIRTUAL_P (clone) = 0; if (TREE_CODE (clone) != TEMPLATE_DECL) DECL_VINDEX (clone) = NULL_TREE; } /* If there was an in-charge parameter, drop it from the function type. */ if (DECL_HAS_IN_CHARGE_PARM_P (clone)) { tree basetype; tree parmtypes; tree exceptions; exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (clone)); basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (clone)); parmtypes = TYPE_ARG_TYPES (TREE_TYPE (clone)); /* Skip the `this' parameter. */ parmtypes = TREE_CHAIN (parmtypes); /* Skip the in-charge parameter. */ parmtypes = TREE_CHAIN (parmtypes); /* If this is subobject constructor or destructor, add the vtt parameter. */ if (DECL_NEEDS_VTT_PARM_P (clone)) parmtypes = hash_tree_chain (vtt_parm_type, parmtypes); TREE_TYPE (clone) = build_cplus_method_type (basetype, TREE_TYPE (TREE_TYPE (clone)), parmtypes); if (exceptions) TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), exceptions); } /* Copy the function parameters. But, DECL_ARGUMENTS aren't function parameters; instead, those are the template parameters. */ if (TREE_CODE (clone) != TEMPLATE_DECL) { DECL_ARGUMENTS (clone) = copy_list (DECL_ARGUMENTS (clone)); /* Remove the in-charge parameter. */ if (DECL_HAS_IN_CHARGE_PARM_P (clone)) { TREE_CHAIN (DECL_ARGUMENTS (clone)) = TREE_CHAIN (TREE_CHAIN (DECL_ARGUMENTS (clone))); DECL_HAS_IN_CHARGE_PARM_P (clone) = 0; } /* Add the VTT parameter. */ if (DECL_NEEDS_VTT_PARM_P (clone)) { tree parm; parm = build_artificial_parm (vtt_parm_identifier, vtt_parm_type); TREE_CHAIN (parm) = TREE_CHAIN (DECL_ARGUMENTS (clone)); TREE_CHAIN (DECL_ARGUMENTS (clone)) = parm; } for (parms = DECL_ARGUMENTS (clone); parms; parms = TREE_CHAIN (parms)) { DECL_CONTEXT (parms) = clone; copy_lang_decl (parms); } } /* Mangle the function name. */ set_mangled_name_for_decl (clone); /* Create the RTL for this function. */ DECL_RTL (clone) = NULL_RTX; rest_of_decl_compilation (clone, NULL, /*top_level=*/1, at_eof); /* Make it easy to find the CLONE given the FN. */ TREE_CHAIN (clone) = TREE_CHAIN (fn); TREE_CHAIN (fn) = clone; /* If this is a template, handle the DECL_TEMPLATE_RESULT as well. */ if (TREE_CODE (clone) == TEMPLATE_DECL) { tree result; DECL_TEMPLATE_RESULT (clone) = build_clone (DECL_TEMPLATE_RESULT (clone), name); result = DECL_TEMPLATE_RESULT (clone); DECL_TEMPLATE_INFO (result) = copy_node (DECL_TEMPLATE_INFO (result)); DECL_TI_TEMPLATE (result) = clone; } else if (DECL_DEFERRED_FN (fn)) defer_fn (clone); return clone; } /* Produce declarations for all appropriate clones of FN. If UPDATE_METHOD_VEC_P is non-zero, the clones are added to the CLASTYPE_METHOD_VEC as well. */ void clone_function_decl (fn, update_method_vec_p) tree fn; int update_method_vec_p; { tree clone; if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn)) { /* For each constructor, we need two variants: an in-charge version and a not-in-charge version. */ clone = build_clone (fn, complete_ctor_identifier); if (update_method_vec_p) add_method (DECL_CONTEXT (clone), clone, /*error_p=*/0); clone = build_clone (fn, base_ctor_identifier); if (update_method_vec_p) add_method (DECL_CONTEXT (clone), clone, /*error_p=*/0); } else { my_friendly_assert (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn), 20000411); /* For each destructor, we need three variants: an in-charge version, a not-in-charge version, and an in-charge deleting version. We clone the deleting version first because that means it will go second on the TYPE_METHODS list -- and that corresponds to the correct layout order in the virtual function table. */ clone = build_clone (fn, deleting_dtor_identifier); if (update_method_vec_p) add_method (DECL_CONTEXT (clone), clone, /*error_p=*/0); clone = build_clone (fn, complete_dtor_identifier); if (update_method_vec_p) add_method (DECL_CONTEXT (clone), clone, /*error_p=*/0); clone = build_clone (fn, base_dtor_identifier); if (update_method_vec_p) add_method (DECL_CONTEXT (clone), clone, /*error_p=*/0); } } /* For each of the constructors and destructors in T, create an in-charge and not-in-charge variant. */ static void clone_constructors_and_destructors (t) tree t; { tree fns; /* We only clone constructors and destructors under the new ABI. */ if (!flag_new_abi) return; /* If for some reason we don't have a CLASSTYPE_METHOD_VEC, we bail out now. */ if (!CLASSTYPE_METHOD_VEC (t)) return; for (fns = CLASSTYPE_CONSTRUCTORS (t); fns; fns = OVL_NEXT (fns)) clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1); for (fns = CLASSTYPE_DESTRUCTORS (t); fns; fns = OVL_NEXT (fns)) clone_function_decl (OVL_CURRENT (fns), /*update_method_vec_p=*/1); } /* Remove all zero-width bit-fields from T. */ static void remove_zero_width_bit_fields (t) tree t; { tree *fieldsp; fieldsp = &TYPE_FIELDS (t); while (*fieldsp) { if (TREE_CODE (*fieldsp) == FIELD_DECL && DECL_C_BIT_FIELD (*fieldsp) && DECL_INITIAL (*fieldsp)) *fieldsp = TREE_CHAIN (*fieldsp); else fieldsp = &TREE_CHAIN (*fieldsp); } } /* Check the validity of the bases and members declared in T. Add any implicitly-generated functions (like copy-constructors and assignment operators). Compute various flag bits (like CLASSTYPE_NON_POD_T) for T. This routine works purely at the C++ level: i.e., independently of the ABI in use. */ static void check_bases_and_members (t, empty_p) tree t; int *empty_p; { /* Nonzero if we are not allowed to generate a default constructor for this case. */ int cant_have_default_ctor; /* Nonzero if the implicitly generated copy constructor should take a non-const reference argument. */ int cant_have_const_ctor; /* Nonzero if the the implicitly generated assignment operator should take a non-const reference argument. */ int no_const_asn_ref; tree access_decls; /* By default, we use const reference arguments and generate default constructors. */ cant_have_default_ctor = 0; cant_have_const_ctor = 0; no_const_asn_ref = 0; /* Assume that the class is nearly empty; we'll clear this flag if it turns out not to be nearly empty. */ CLASSTYPE_NEARLY_EMPTY_P (t) = 1; /* Check all the base-classes. */ check_bases (t, &cant_have_default_ctor, &cant_have_const_ctor, &no_const_asn_ref); /* Check all the data member declarations. */ check_field_decls (t, &access_decls, empty_p, &cant_have_default_ctor, &cant_have_const_ctor, &no_const_asn_ref); /* Check all the method declarations. */ check_methods (t); /* A nearly-empty class has to be vptr-containing; a nearly empty class contains just a vptr. */ if (!TYPE_CONTAINS_VPTR_P (t)) CLASSTYPE_NEARLY_EMPTY_P (t) = 0; /* Do some bookkeeping that will guide the generation of implicitly declared member functions. */ TYPE_HAS_COMPLEX_INIT_REF (t) |= (TYPE_HAS_INIT_REF (t) || TYPE_USES_VIRTUAL_BASECLASSES (t) || TYPE_POLYMORPHIC_P (t)); TYPE_NEEDS_CONSTRUCTING (t) |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_USES_VIRTUAL_BASECLASSES (t) || TYPE_POLYMORPHIC_P (t)); CLASSTYPE_NON_AGGREGATE (t) |= (TYPE_HAS_CONSTRUCTOR (t) || TYPE_POLYMORPHIC_P (t)); CLASSTYPE_NON_POD_P (t) |= (CLASSTYPE_NON_AGGREGATE (t) || TYPE_HAS_DESTRUCTOR (t) || TYPE_HAS_ASSIGN_REF (t)); TYPE_HAS_REAL_ASSIGN_REF (t) |= TYPE_HAS_ASSIGN_REF (t); TYPE_HAS_COMPLEX_ASSIGN_REF (t) |= TYPE_HAS_ASSIGN_REF (t) || TYPE_USES_VIRTUAL_BASECLASSES (t); /* Synthesize any needed methods. Note that methods will be synthesized for anonymous unions; grok_x_components undoes that. */ add_implicitly_declared_members (t, cant_have_default_ctor, cant_have_const_ctor, no_const_asn_ref); /* Create the in-charge and not-in-charge variants of constructors and destructors. */ clone_constructors_and_destructors (t); /* Process the using-declarations. */ for (; access_decls; access_decls = TREE_CHAIN (access_decls)) handle_using_decl (TREE_VALUE (access_decls), t); /* Build and sort the CLASSTYPE_METHOD_VEC. */ finish_struct_methods (t); } /* If T needs a pointer to its virtual function table, set TYPE_VFIELD accordingly. If a new vfield was created (because T doesn't have a primary base class), then the newly created field is returned. It is not added to the TYPE_FIELDS list; it is the caller's responsibility to do that. */ static tree create_vtable_ptr (t, empty_p, vfuns_p, new_virtuals_p, overridden_virtuals_p) tree t; int *empty_p; int *vfuns_p; tree *new_virtuals_p; tree *overridden_virtuals_p; { tree fn; /* Loop over the virtual functions, adding them to our various vtables. */ for (fn = TYPE_METHODS (t); fn; fn = TREE_CHAIN (fn)) if (DECL_VINDEX (fn) && !(flag_new_abi && DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn))) add_virtual_function (new_virtuals_p, overridden_virtuals_p, vfuns_p, fn, t); /* If we couldn't find an appropriate base class, create a new field here. Even if there weren't any new virtual functions, we might need a new virtual function table if we're supposed to include vptrs in all classes that need them. */ if (!TYPE_VFIELD (t) && (*vfuns_p || (TYPE_CONTAINS_VPTR_P (t) && vptrs_present_everywhere_p ()))) { /* We build this decl with vtbl_ptr_type_node, which is a `vtable_entry_type*'. It might seem more precise to use `vtable_entry_type (*)[N]' where N is the number of firtual functions. However, that would require the vtable pointer in base classes to have a different type than the vtable pointer in derived classes. We could make that happen, but that still wouldn't solve all the problems. In particular, the type-based alias analysis code would decide that assignments to the base class vtable pointer can't alias assignments to the derived class vtable pointer, since they have different types. Thus, in an derived class destructor, where the base class constructor was inlined, we could generate bad code for setting up the vtable pointer. Therefore, we use one type for all vtable pointers. We still use a type-correct type; it's just doesn't indicate the array bounds. That's better than using `void*' or some such; it's cleaner, and it let's the alias analysis code know that these stores cannot alias stores to void*! */ TYPE_VFIELD (t) = build_vtbl_or_vbase_field (get_vfield_name (t), get_identifier (VFIELD_BASE), vtbl_ptr_type_node, t, t, empty_p); if (flag_new_abi && CLASSTYPE_N_BASECLASSES (t)) /* If there were any baseclasses, they can't possibly be at offset zero any more, because that's where the vtable pointer is. So, converting to a base class is going to take work. */ TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (t) = 1; return TYPE_VFIELD (t); } return NULL_TREE; } /* Fixup the inline function given by INFO now that the class is complete. */ static void fixup_pending_inline (fn) tree fn; { if (DECL_PENDING_INLINE_INFO (fn)) { tree args = DECL_ARGUMENTS (fn); while (args) { DECL_CONTEXT (args) = fn; args = TREE_CHAIN (args); } } } /* Fixup the inline methods and friends in TYPE now that TYPE is complete. */ static void fixup_inline_methods (type) tree type; { tree method = TYPE_METHODS (type); if (method && TREE_CODE (method) == TREE_VEC) { if (TREE_VEC_ELT (method, 1)) method = TREE_VEC_ELT (method, 1); else if (TREE_VEC_ELT (method, 0)) method = TREE_VEC_ELT (method, 0); else method = TREE_VEC_ELT (method, 2); } /* Do inline member functions. */ for (; method; method = TREE_CHAIN (method)) fixup_pending_inline (method); /* Do friends. */ for (method = CLASSTYPE_INLINE_FRIENDS (type); method; method = TREE_CHAIN (method)) fixup_pending_inline (TREE_VALUE (method)); CLASSTYPE_INLINE_FRIENDS (type) = NULL_TREE; } /* Add OFFSET to all base types of BINFO which is a base in the hierarchy dominated by T. OFFSET, which is a type offset, is number of bytes. */ static void propagate_binfo_offsets (binfo, offset) tree binfo; tree offset; { int i; tree primary_binfo; /* Update BINFO's offset. */ BINFO_OFFSET (binfo) = convert (sizetype, size_binop (PLUS_EXPR, convert (ssizetype, BINFO_OFFSET (binfo)), offset)); /* Find the primary base class. */ primary_binfo = get_primary_binfo (binfo); /* Scan all of the bases, pushing the BINFO_OFFSET adjust downwards. */ for (i = -1; i < BINFO_N_BASETYPES (binfo); ++i) { tree base_binfo; /* On the first through the loop, do the primary base. Because the primary base need not be an immediate base, we must handle the primary base specially. */ if (i == -1) { if (!primary_binfo) continue; base_binfo = primary_binfo; } else { base_binfo = BINFO_BASETYPE (binfo, i); /* Don't do the primary base twice. */ if (base_binfo == primary_binfo) continue; } /* Skip virtual bases that aren't our primary base. */ if (TREE_VIA_VIRTUAL (base_binfo) && BINFO_PRIMARY_BASE_OF (base_binfo) != binfo) continue; propagate_binfo_offsets (base_binfo, offset); } } /* Called via dfs_walk from layout_virtual bases. */ static tree dfs_set_offset_for_unshared_vbases (binfo, data) tree binfo; void *data; { /* If this is a virtual base, make sure it has the same offset as the shared copy. If it's a primary base, then we know it's correct. */ if (TREE_VIA_VIRTUAL (binfo) && !BINFO_PRIMARY_MARKED_P (binfo)) { tree t = (tree) data; tree vbase; tree offset; vbase = binfo_for_vbase (BINFO_TYPE (binfo), t); offset = size_diffop (BINFO_OFFSET (vbase), BINFO_OFFSET (binfo)); propagate_binfo_offsets (binfo, offset); } return NULL_TREE; } /* Set BINFO_OFFSET for all of the virtual bases for T. Update TYPE_ALIGN and TYPE_SIZE for T. OFFSETS gives the location of empty subobjects of T. */ static void layout_virtual_bases (t, offsets) tree t; splay_tree offsets; { tree vbases; unsigned HOST_WIDE_INT dsize; unsigned HOST_WIDE_INT eoc; if (CLASSTYPE_N_BASECLASSES (t) == 0) return; #ifdef STRUCTURE_SIZE_BOUNDARY /* Packed structures don't need to have minimum size. */ if (! TYPE_PACKED (t)) TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), STRUCTURE_SIZE_BOUNDARY); #endif /* DSIZE is the size of the class without the virtual bases. */ dsize = tree_low_cst (TYPE_SIZE (t), 1); /* Make every class have alignment of at least one. */ TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), BITS_PER_UNIT); /* Go through the virtual bases, allocating space for each virtual base that is not already a primary base class. Under the new ABI, these are allocated according to a depth-first left-to-right postorder traversal; in the new ABI, inheritance graph order is used instead. */ for (vbases = (flag_new_abi ? TYPE_BINFO (t) : CLASSTYPE_VBASECLASSES (t)); vbases; vbases = TREE_CHAIN (vbases)) { tree vbase; if (flag_new_abi) { if (!TREE_VIA_VIRTUAL (vbases)) continue; vbase = binfo_for_vbase (BINFO_TYPE (vbases), t); } else vbase = TREE_VALUE (vbases); if (!BINFO_PRIMARY_MARKED_P (vbase)) { /* This virtual base is not a primary base of any class in the hierarchy, so we have to add space for it. */ tree basetype; unsigned int desired_align; basetype = BINFO_TYPE (vbase); if (flag_new_abi) desired_align = CLASSTYPE_ALIGN (basetype); else /* Under the old ABI, virtual bases were aligned as for the entire base object (including its virtual bases). That's wasteful, in general. */ desired_align = TYPE_ALIGN (basetype); TYPE_ALIGN (t) = MAX (TYPE_ALIGN (t), desired_align); /* Add padding so that we can put the virtual base class at an appropriately aligned offset. */ dsize = CEIL (dsize, desired_align) * desired_align; /* Under the new ABI, we try to squish empty virtual bases in just like ordinary empty bases. */ if (flag_new_abi && is_empty_class (basetype)) layout_empty_base (vbase, size_int (CEIL (dsize, BITS_PER_UNIT)), offsets); else { tree offset; offset = ssize_int (CEIL (dsize, BITS_PER_UNIT)); offset = size_diffop (offset, convert (ssizetype, BINFO_OFFSET (vbase))); /* And compute the offset of the virtual base. */ propagate_binfo_offsets (vbase, offset); /* Every virtual baseclass takes a least a UNIT, so that we can take it's address and get something different for each base. */ dsize += MAX (BITS_PER_UNIT, tree_low_cst (CLASSTYPE_SIZE (basetype), 0)); } /* Keep track of the offsets assigned to this virtual base. */ record_subobject_offsets (BINFO_TYPE (vbase), BINFO_OFFSET (vbase), offsets, /*vbases_p=*/0); } } /* Now, go through the TYPE_BINFO hierarchy, setting the BINFO_OFFSETs correctly for all non-primary copies of the virtual bases and their direct and indirect bases. The ambiguity checks in get_base_distance depend on the BINFO_OFFSETs being set correctly. */ dfs_walk (TYPE_BINFO (t), dfs_set_offset_for_unshared_vbases, NULL, t); /* If we had empty base classes that protruded beyond the end of the class, we didn't update DSIZE above; we were hoping to overlay multiple such bases at the same location. */ eoc = end_of_class (t, /*include_virtuals_p=*/1); if (eoc * BITS_PER_UNIT > dsize) dsize = (eoc + 1) * BITS_PER_UNIT; /* Now, make sure that the total size of the type is a multiple of its alignment. */ dsize = CEIL (dsize, TYPE_ALIGN (t)) * TYPE_ALIGN (t); TYPE_SIZE (t) = bitsize_int (dsize); TYPE_SIZE_UNIT (t) = convert (sizetype, size_binop (CEIL_DIV_EXPR, TYPE_SIZE (t), bitsize_unit_node)); /* Check for ambiguous virtual bases. */ if (extra_warnings) for (vbases = CLASSTYPE_VBASECLASSES (t); vbases; vbases = TREE_CHAIN (vbases)) { tree basetype = BINFO_TYPE (TREE_VALUE (vbases)); if (get_base_distance (basetype, t, 0, (tree*)0) == -2) cp_warning ("virtual base `%T' inaccessible in `%T' due to ambiguity", basetype, t); } } /* Returns the offset of the byte just past the end of the base class with the highest offset in T. If INCLUDE_VIRTUALS_P is zero, then only non-virtual bases are included. */ static unsigned HOST_WIDE_INT end_of_class (t, include_virtuals_p) tree t; int include_virtuals_p; { unsigned HOST_WIDE_INT result = 0; int i; for (i = 0; i < CLASSTYPE_N_BASECLASSES (t); ++i) { tree base_binfo; tree offset; unsigned HOST_WIDE_INT end_of_base; base_binfo = BINFO_BASETYPE (TYPE_BINFO (t), i); if (!include_virtuals_p && TREE_VIA_VIRTUAL (base_binfo) && !BINFO_PRIMARY_MARKED_P (base_binfo)) continue; offset = size_binop (PLUS_EXPR, BINFO_OFFSET (base_binfo), CLASSTYPE_SIZE_UNIT (BINFO_TYPE (base_binfo))); end_of_base = tree_low_cst (offset, /*pos=*/1); if (end_of_base > result) result = end_of_base; } return result; } /* Compare two INTEGER_CSTs K1 and K2. */ static int splay_tree_compare_integer_csts (k1, k2) splay_tree_key k1; splay_tree_key k2; { return tree_int_cst_compare ((tree) k1, (tree) k2); } /* Calculate the TYPE_SIZE, TYPE_ALIGN, etc for T. Calculate BINFO_OFFSETs for all of the base-classes. Position the vtable pointer. */ static void layout_class_type (t, empty_p, vfuns_p, new_virtuals_p, overridden_virtuals_p) tree t; int *empty_p; int *vfuns_p; tree *new_virtuals_p; tree *overridden_virtuals_p; { tree non_static_data_members; tree field; tree vptr; record_layout_info rli; unsigned HOST_WIDE_INT eoc; /* Maps offsets (represented as INTEGER_CSTs) to a TREE_LIST of types that appear at that offset. */ splay_tree empty_base_offsets; /* Keep track of the first non-static data member. */ non_static_data_members = TYPE_FIELDS (t); /* Start laying out the record. */ rli = start_record_layout (t); /* If possible, we reuse the virtual function table pointer from one of our base classes. */ determine_primary_base (t, vfuns_p); /* Create a pointer to our virtual function table. */ vptr = create_vtable_ptr (t, empty_p, vfuns_p, new_virtuals_p, overridden_virtuals_p); /* Under the new ABI, the vptr is always the first thing in the class. */ if (flag_new_abi && vptr) { TYPE_FIELDS (t) = chainon (vptr, TYPE_FIELDS (t)); place_field (rli, vptr); } /* Build FIELD_DECLs for all of the non-virtual base-types. */ empty_base_offsets = splay_tree_new (splay_tree_compare_integer_csts, NULL, NULL); build_base_fields (rli, empty_p, empty_base_offsets); /* Add pointers to all of our virtual base-classes. */ TYPE_FIELDS (t) = chainon (build_vbase_pointer_fields (rli, empty_p), TYPE_FIELDS (t)); /* CLASSTYPE_INLINE_FRIENDS is really TYPE_NONCOPIED_PARTS. Thus, we have to save this before we start modifying TYPE_NONCOPIED_PARTS. */ fixup_inline_methods (t); /* Layout the non-static data members. */ for (field = non_static_data_members; field; field = TREE_CHAIN (field)) { tree type; tree padding; /* We still pass things that aren't non-static data members to the back-end, in case it wants to do something with them. */ if (TREE_CODE (field) != FIELD_DECL) { place_field (rli, field); continue; } type = TREE_TYPE (field); /* If this field is a bit-field whose width is greater than its type, then there are some special rules for allocating it under the new ABI. Under the old ABI, there were no special rules, but the back-end can't handle bitfields longer than a `long long', so we use the same mechanism. */ if (DECL_C_BIT_FIELD (field) && ((flag_new_abi && INT_CST_LT (TYPE_SIZE (type), DECL_SIZE (field))) || (!flag_new_abi && 0 < compare_tree_int (DECL_SIZE (field), TYPE_PRECISION (long_long_unsigned_type_node))))) { integer_type_kind itk; tree integer_type; /* We must allocate the bits as if suitably aligned for the longest integer type that fits in this many bits. type of the field. Then, we are supposed to use the left over bits as additional padding. */ for (itk = itk_char; itk != itk_none; ++itk) if (INT_CST_LT (DECL_SIZE (field), TYPE_SIZE (integer_types[itk]))) break; /* ITK now indicates a type that is too large for the field. We have to back up by one to find the largest type that fits. */ integer_type = integer_types[itk - 1]; padding = size_binop (MINUS_EXPR, DECL_SIZE (field), TYPE_SIZE (integer_type)); DECL_SIZE (field) = TYPE_SIZE (integer_type); DECL_ALIGN (field) = TYPE_ALIGN (integer_type); DECL_USER_ALIGN (field) = TYPE_USER_ALIGN (integer_type); } else padding = NULL_TREE; layout_nonempty_base_or_field (rli, field, NULL_TREE, empty_base_offsets); /* If we needed additional padding after this field, add it now. */ if (padding) { tree padding_field; padding_field = build_decl (FIELD_DECL, NULL_TREE, char_type_node); DECL_BIT_FIELD (padding_field) = 1; DECL_SIZE (padding_field) = padding; DECL_ALIGN (padding_field) = 1; DECL_USER_ALIGN (padding_field) = 0; layout_nonempty_base_or_field (rli, padding_field, NULL_TREE, empty_base_offsets); } } /* It might be the case that we grew the class to allocate a zero-sized base class. That won't be reflected in RLI, yet, because we are willing to overlay multiple bases at the same offset. However, now we need to make sure that RLI is big enough to reflect the entire class. */ eoc = end_of_class (t, /*include_virtuals_p=*/0); if (TREE_CODE (rli_size_unit_so_far (rli)) == INTEGER_CST && compare_tree_int (rli_size_unit_so_far (rli), eoc) < 0) { /* We don't handle zero-sized base classes specially under the old ABI, so if we get here, we had better be operating under the new ABI rules. */ my_friendly_assert (flag_new_abi, 20000321); rli->offset = size_binop (MAX_EXPR, rli->offset, size_int (eoc + 1)); rli->bitpos = bitsize_zero_node; } /* We make all structures have at least one element, so that they have non-zero size. In the new ABI, the class may be empty even if it has basetypes. Therefore, we add the fake field after all the other fields; if there are already FIELD_DECLs on the list, their offsets will not be disturbed. */ if (*empty_p) { tree padding; padding = build_decl (FIELD_DECL, NULL_TREE, char_type_node); place_field (rli, padding); TYPE_NONCOPIED_PARTS (t) = tree_cons (NULL_TREE, padding, TYPE_NONCOPIED_PARTS (t)); TREE_STATIC (TYPE_NONCOPIED_PARTS (t)) = 1; } /* Under the old ABI, the vptr comes at the very end of the class. */ if (!flag_new_abi && vptr) { place_field (rli, vptr); TYPE_FIELDS (t) = chainon (TYPE_FIELDS (t), vptr); } /* Let the back-end lay out the type. Note that at this point we have only included non-virtual base-classes; we will lay out the virtual base classes later. So, the TYPE_SIZE/TYPE_ALIGN after this call are not necessarily correct; they are just the size and alignment when no virtual base clases are used. */ finish_record_layout (rli); /* Delete all zero-width bit-fields from the list of fields. Now that the type is laid out they are no longer important. */ remove_zero_width_bit_fields (t); /* Remember the size and alignment of the class before adding the virtual bases. */ if (*empty_p && flag_new_abi) { CLASSTYPE_SIZE (t) = bitsize_zero_node; CLASSTYPE_SIZE_UNIT (t) = size_zero_node; } else if (flag_new_abi) { CLASSTYPE_SIZE (t) = TYPE_BINFO_SIZE (t); CLASSTYPE_SIZE_UNIT (t) = TYPE_BINFO_SIZE_UNIT (t); } else { CLASSTYPE_SIZE (t) = TYPE_SIZE (t); CLASSTYPE_SIZE_UNIT (t) = TYPE_SIZE_UNIT (t); } CLASSTYPE_ALIGN (t) = TYPE_ALIGN (t); CLASSTYPE_USER_ALIGN (t) = TYPE_USER_ALIGN (t); /* Set the TYPE_DECL for this type to contain the right value for DECL_OFFSET, so that we can use it as part of a COMPONENT_REF for multiple inheritance. */ layout_decl (TYPE_MAIN_DECL (t), 0); /* Now fix up any virtual base class types that we left lying around. We must get these done before we try to lay out the virtual function table. As a side-effect, this will remove the base subobject fields. */ layout_virtual_bases (t, empty_base_offsets); /* Clean up. */ splay_tree_delete (empty_base_offsets); } /* Create a RECORD_TYPE or UNION_TYPE node for a C struct or union declaration (or C++ class declaration). For C++, we must handle the building of derived classes. Also, C++ allows static class members. The way that this is handled is to keep the field name where it is (as the DECL_NAME of the field), and place the overloaded decl in the bit position of the field. layout_record and layout_union will know about this. More C++ hair: inline functions have text in their DECL_PENDING_INLINE_INFO nodes which must somehow be parsed into meaningful tree structure. After the struct has been laid out, set things up so that this can happen. And still more: virtual functions. In the case of single inheritance, when a new virtual function is seen which redefines a virtual function from the base class, the new virtual function is placed into the virtual function table at exactly the same address that it had in the base class. When this is extended to multiple inheritance, the same thing happens, except that multiple virtual function tables must be maintained. The first virtual function table is treated in exactly the same way as in the case of single inheritance. Additional virtual function tables have different DELTAs, which tell how to adjust `this' to point to the right thing. ATTRIBUTES is the set of decl attributes to be applied, if any. */ void finish_struct_1 (t) tree t; { tree x; int vfuns; /* The NEW_VIRTUALS is a TREE_LIST. The TREE_VALUE of each node is a FUNCTION_DECL. Each of these functions is a virtual function declared in T that does not override any virtual function from a base class. */ tree new_virtuals = NULL_TREE; /* The OVERRIDDEN_VIRTUALS list is like the NEW_VIRTUALS list, except that each declaration here overrides the declaration from a base class. */ tree overridden_virtuals = NULL_TREE; int n_fields = 0; tree vfield; int empty = 1; if (COMPLETE_TYPE_P (t)) { if (IS_AGGR_TYPE (t)) cp_error ("redefinition of `%#T'", t); else my_friendly_abort (172); popclass (); return; } GNU_xref_decl (current_function_decl, t); /* If this type was previously laid out as a forward reference, make sure we lay it out again. */ TYPE_SIZE (t) = NULL_TREE; CLASSTYPE_GOT_SEMICOLON (t) = 0; CLASSTYPE_PRIMARY_BINFO (t) = NULL_TREE; vfuns = 0; CLASSTYPE_RTTI (t) = NULL_TREE; /* Do end-of-class semantic processing: checking the validity of the bases and members and add implicitly generated methods. */ check_bases_and_members (t, &empty); /* Layout the class itself. */ layout_class_type (t, &empty, &vfuns, &new_virtuals, &overridden_virtuals); /* Set up the DECL_FIELD_BITPOS of the vfield if we need to, as we might need to know it for setting up the offsets in the vtable (or in thunks) below. */ vfield = TYPE_VFIELD (t); if (vfield != NULL_TREE && DECL_FIELD_CONTEXT (vfield) != t) { tree binfo = get_binfo (DECL_FIELD_CONTEXT (vfield), t, 0); vfield = copy_decl (vfield); DECL_FIELD_CONTEXT (vfield) = t; DECL_FIELD_OFFSET (vfield) = size_binop (PLUS_EXPR, BINFO_OFFSET (binfo), DECL_FIELD_OFFSET (vfield)); TYPE_VFIELD (t) = vfield; } overridden_virtuals = modify_all_vtables (t, &vfuns, nreverse (overridden_virtuals)); /* If we created a new vtbl pointer for this class, add it to the list. */ if (TYPE_VFIELD (t) && !CLASSTYPE_HAS_PRIMARY_BASE_P (t)) CLASSTYPE_VFIELDS (t) = chainon (CLASSTYPE_VFIELDS (t), build_tree_list (NULL_TREE, t)); /* If necessary, create the primary vtable for this class. */ if (new_virtuals || overridden_virtuals || (TYPE_CONTAINS_VPTR_P (t) && vptrs_present_everywhere_p ())) { new_virtuals = nreverse (new_virtuals); /* We must enter these virtuals into the table. */ if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t)) build_primary_vtable (NULL_TREE, t); else if (! BINFO_NEW_VTABLE_MARKED (TYPE_BINFO (t), t)) /* Here we know enough to change the type of our virtual function table, but we will wait until later this function. */ build_primary_vtable (CLASSTYPE_PRIMARY_BINFO (t), t); /* If this type has basetypes with constructors, then those constructors might clobber the virtual function table. But they don't if the derived class shares the exact vtable of the base class. */ CLASSTYPE_NEEDS_VIRTUAL_REINIT (t) = 1; } /* If we didn't need a new vtable, see if we should copy one from the base. */ else if (CLASSTYPE_HAS_PRIMARY_BASE_P (t)) { tree binfo = CLASSTYPE_PRIMARY_BINFO (t); /* If this class uses a different vtable than its primary base then when we will need to initialize our vptr after the base class constructor runs. */ if (TYPE_BINFO_VTABLE (t) != BINFO_VTABLE (binfo)) CLASSTYPE_NEEDS_VIRTUAL_REINIT (t) = 1; } if (TYPE_CONTAINS_VPTR_P (t)) { if (TYPE_BINFO_VTABLE (t)) my_friendly_assert (DECL_VIRTUAL_P (TYPE_BINFO_VTABLE (t)), 20000116); if (!CLASSTYPE_HAS_PRIMARY_BASE_P (t)) my_friendly_assert (TYPE_BINFO_VIRTUALS (t) == NULL_TREE, 20000116); CLASSTYPE_VSIZE (t) = vfuns; /* Entries for virtual functions defined in the primary base are followed by entries for new functions unique to this class. */ TYPE_BINFO_VIRTUALS (t) = chainon (TYPE_BINFO_VIRTUALS (t), new_virtuals); /* Finally, add entries for functions that override virtuals from non-primary bases. */ TYPE_BINFO_VIRTUALS (t) = chainon (TYPE_BINFO_VIRTUALS (t), overridden_virtuals); } finish_struct_bits (t); /* Complete the rtl for any static member objects of the type we're working on. */ for (x = TYPE_FIELDS (t); x; x = TREE_CHAIN (x)) { if (TREE_CODE (x) == VAR_DECL && TREE_STATIC (x) && TREE_TYPE (x) == t) { DECL_MODE (x) = TYPE_MODE (t); make_decl_rtl (x, NULL, 0); } } /* Done with FIELDS...now decide whether to sort these for faster lookups later. The C front-end only does this when n_fields > 15. We use a smaller number because most searches fail (succeeding ultimately as the search bores through the inheritance hierarchy), and we want this failure to occur quickly. */ n_fields = count_fields (TYPE_FIELDS (t)); if (n_fields > 7) { tree field_vec = make_tree_vec (n_fields); add_fields_to_vec (TYPE_FIELDS (t), field_vec, 0); qsort (&TREE_VEC_ELT (field_vec, 0), n_fields, sizeof (tree), (int (*)(const void *, const void *))field_decl_cmp); if (! DECL_LANG_SPECIFIC (TYPE_MAIN_DECL (t))) retrofit_lang_decl (TYPE_MAIN_DECL (t)); DECL_SORTED_FIELDS (TYPE_MAIN_DECL (t)) = field_vec; } if (TYPE_HAS_CONSTRUCTOR (t)) { tree vfields = CLASSTYPE_VFIELDS (t); while (vfields) { /* Mark the fact that constructor for T could affect anybody inheriting from T who wants to initialize vtables for VFIELDS's type. */ if (VF_DERIVED_VALUE (vfields)) TREE_ADDRESSABLE (vfields) = 1; vfields = TREE_CHAIN (vfields); } } /* Make the rtl for any new vtables we have created, and unmark the base types we marked. */ finish_vtbls (t); /* Build the VTT for T. */ build_vtt (t); if (TYPE_VFIELD (t)) { /* In addition to this one, all the other vfields should be listed. */ /* Before that can be done, we have to have FIELD_DECLs for them, and a place to find them. */ TYPE_NONCOPIED_PARTS (t) = tree_cons (default_conversion (TYPE_BINFO_VTABLE (t)), TYPE_VFIELD (t), TYPE_NONCOPIED_PARTS (t)); if (warn_nonvdtor && TYPE_HAS_DESTRUCTOR (t) && DECL_VINDEX (TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (t), 1)) == NULL_TREE) cp_warning ("`%#T' has virtual functions but non-virtual destructor", t); } hack_incomplete_structures (t); if (warn_overloaded_virtual) warn_hidden (t); maybe_suppress_debug_info (t); /* Finish debugging output for this type. */ rest_of_type_compilation (t, ! LOCAL_CLASS_P (t)); } /* When T was built up, the member declarations were added in reverse order. Rearrange them to declaration order. */ void unreverse_member_declarations (t) tree t; { tree next; tree prev; tree x; /* The TYPE_FIELDS, TYPE_METHODS, and CLASSTYPE_TAGS are all in reverse order. Put them in declaration order now. */ TYPE_METHODS (t) = nreverse (TYPE_METHODS (t)); CLASSTYPE_TAGS (t) = nreverse (CLASSTYPE_TAGS (t)); /* Actually, for the TYPE_FIELDS, only the non TYPE_DECLs are in reverse order, so we can't just use nreverse. */ prev = NULL_TREE; for (x = TYPE_FIELDS (t); x && TREE_CODE (x) != TYPE_DECL; x = next) { next = TREE_CHAIN (x); TREE_CHAIN (x) = prev; prev = x; } if (prev) { TREE_CHAIN (TYPE_FIELDS (t)) = x; if (prev) TYPE_FIELDS (t) = prev; } } tree finish_struct (t, attributes) tree t, attributes; { /* Now that we've got all the field declarations, reverse everything as necessary. */ unreverse_member_declarations (t); cplus_decl_attributes (t, attributes, NULL_TREE); if (processing_template_decl) { finish_struct_methods (t); TYPE_SIZE (t) = bitsize_zero_node; } else finish_struct_1 (t); TYPE_BEING_DEFINED (t) = 0; if (current_class_type) popclass (); else error ("trying to finish struct, but kicked out due to previous parse errors."); if (processing_template_decl) { tree scope = current_scope (); if (scope && TREE_CODE (scope) == FUNCTION_DECL) add_stmt (build_min (TAG_DEFN, t)); } return t; } /* Return the dynamic type of INSTANCE, if known. Used to determine whether the virtual function table is needed or not. *NONNULL is set iff INSTANCE can be known to be nonnull, regardless of our knowledge of its type. *NONNULL should be initialized before this function is called. */ static tree fixed_type_or_null (instance, nonnull) tree instance; int *nonnull; { switch (TREE_CODE (instance)) { case INDIRECT_REF: /* Check that we are not going through a cast of some sort. */ if (TREE_TYPE (instance) == TREE_TYPE (TREE_TYPE (TREE_OPERAND (instance, 0)))) instance = TREE_OPERAND (instance, 0); /* fall through... */ case CALL_EXPR: /* This is a call to a constructor, hence it's never zero. */ if (TREE_HAS_CONSTRUCTOR (instance)) { if (nonnull) *nonnull = 1; return TREE_TYPE (instance); } return NULL_TREE; case SAVE_EXPR: /* This is a call to a constructor, hence it's never zero. */ if (TREE_HAS_CONSTRUCTOR (instance)) { if (nonnull) *nonnull = 1; return TREE_TYPE (instance); } return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull); case RTL_EXPR: return NULL_TREE; case PLUS_EXPR: case MINUS_EXPR: if (TREE_CODE (TREE_OPERAND (instance, 1)) == INTEGER_CST) /* Propagate nonnull. */ fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull); if (TREE_CODE (TREE_OPERAND (instance, 0)) == ADDR_EXPR) return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull); return NULL_TREE; case NOP_EXPR: case CONVERT_EXPR: return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull); case ADDR_EXPR: if (nonnull) *nonnull = 1; return fixed_type_or_null (TREE_OPERAND (instance, 0), nonnull); case COMPONENT_REF: return fixed_type_or_null (TREE_OPERAND (instance, 1), nonnull); case VAR_DECL: case FIELD_DECL: if (TREE_CODE (TREE_TYPE (instance)) == ARRAY_TYPE && IS_AGGR_TYPE (TREE_TYPE (TREE_TYPE (instance)))) { if (nonnull) *nonnull = 1; return TREE_TYPE (TREE_TYPE (instance)); } /* fall through... */ case TARGET_EXPR: case PARM_DECL: if (IS_AGGR_TYPE (TREE_TYPE (instance))) { if (nonnull) *nonnull = 1; return TREE_TYPE (instance); } else if (nonnull) { if (instance == current_class_ptr && flag_this_is_variable <= 0) { /* Normally, 'this' must be non-null. */ if (flag_this_is_variable == 0) *nonnull = 1; /* <0 means we're in a constructor and we know our type. */ if (flag_this_is_variable < 0) return TREE_TYPE (TREE_TYPE (instance)); } else if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE) /* Reference variables should be references to objects. */ *nonnull = 1; } return NULL_TREE; default: return NULL_TREE; } } /* Return non-zero if the dynamic type of INSTANCE is known, and equivalent to the static type. We also handle the case where INSTANCE is really a pointer. Used to determine whether the virtual function table is needed or not. *NONNULL is set iff INSTANCE can be known to be nonnull, regardless of our knowledge of its type. *NONNULL should be initialized before this function is called. */ int resolves_to_fixed_type_p (instance, nonnull) tree instance; int *nonnull; { tree t = TREE_TYPE (instance); tree fixed = fixed_type_or_null (instance, nonnull); if (fixed == NULL_TREE) return 0; if (POINTER_TYPE_P (t)) t = TREE_TYPE (t); return same_type_ignoring_top_level_qualifiers_p (t, fixed); } void init_class_processing () { current_class_depth = 0; current_class_stack_size = 10; current_class_stack = (class_stack_node_t) xmalloc (current_class_stack_size * sizeof (struct class_stack_node)); VARRAY_TREE_INIT (local_classes, 8, "local_classes"); ggc_add_tree_varray_root (&local_classes, 1); access_default_node = build_int_2 (0, 0); access_public_node = build_int_2 (ak_public, 0); access_protected_node = build_int_2 (ak_protected, 0); access_private_node = build_int_2 (ak_private, 0); access_default_virtual_node = build_int_2 (4, 0); access_public_virtual_node = build_int_2 (4 | ak_public, 0); access_protected_virtual_node = build_int_2 (4 | ak_protected, 0); access_private_virtual_node = build_int_2 (4 | ak_private, 0); ridpointers[(int) RID_PUBLIC] = access_public_node; ridpointers[(int) RID_PRIVATE] = access_private_node; ridpointers[(int) RID_PROTECTED] = access_protected_node; } /* Set current scope to NAME. CODE tells us if this is a STRUCT, UNION, or ENUM environment. NAME may end up being NULL_TREE if this is an anonymous or late-bound struct (as in "struct { ... } foo;") */ /* Set global variables CURRENT_CLASS_NAME and CURRENT_CLASS_TYPE to appropriate values, found by looking up the type definition of NAME (as a CODE). If MODIFY is 1, we set IDENTIFIER_CLASS_VALUE's of names which can be seen locally to the class. They are shadowed by any subsequent local declaration (including parameter names). If MODIFY is 2, we set IDENTIFIER_CLASS_VALUE's of names which have static meaning (i.e., static members, static member functions, enum declarations, etc). If MODIFY is 3, we set IDENTIFIER_CLASS_VALUE of names which can be seen locally to the class (as in 1), but know that we are doing this for declaration purposes (i.e. friend foo::bar (int)). So that we may avoid calls to lookup_name, we cache the _TYPE nodes of local TYPE_DECLs in the TREE_TYPE field of the name. For multiple inheritance, we perform a two-pass depth-first search of the type lattice. The first pass performs a pre-order search, marking types after the type has had its fields installed in the appropriate IDENTIFIER_CLASS_VALUE slot. The second pass merely unmarks the marked types. If a field or member function name appears in an ambiguous way, the IDENTIFIER_CLASS_VALUE of that name becomes `error_mark_node'. */ void pushclass (type, modify) tree type; int modify; { type = TYPE_MAIN_VARIANT (type); /* Make sure there is enough room for the new entry on the stack. */ if (current_class_depth + 1 >= current_class_stack_size) { current_class_stack_size *= 2; current_class_stack = (class_stack_node_t) xrealloc (current_class_stack, current_class_stack_size * sizeof (struct class_stack_node)); } /* Insert a new entry on the class stack. */ current_class_stack[current_class_depth].name = current_class_name; current_class_stack[current_class_depth].type = current_class_type; current_class_stack[current_class_depth].access = current_access_specifier; current_class_stack[current_class_depth].names_used = 0; current_class_depth++; /* Now set up the new type. */ current_class_name = TYPE_NAME (type); if (TREE_CODE (current_class_name) == TYPE_DECL) current_class_name = DECL_NAME (current_class_name); current_class_type = type; /* By default, things in classes are private, while things in structures or unions are public. */ current_access_specifier = (CLASSTYPE_DECLARED_CLASS (type) ? access_private_node : access_public_node); if (previous_class_type != NULL_TREE && (type != previous_class_type || !COMPLETE_TYPE_P (previous_class_type)) && current_class_depth == 1) { /* Forcibly remove any old class remnants. */ invalidate_class_lookup_cache (); } /* If we're about to enter a nested class, clear IDENTIFIER_CLASS_VALUE for the enclosing classes. */ if (modify && current_class_depth > 1) clear_identifier_class_values (); pushlevel_class (); #if 0 if (CLASSTYPE_TEMPLATE_INFO (type)) overload_template_name (type); #endif if (modify) { if (type != previous_class_type || current_class_depth > 1) push_class_decls (type); else { tree item; /* We are re-entering the same class we just left, so we don't have to search the whole inheritance matrix to find all the decls to bind again. Instead, we install the cached class_shadowed list, and walk through it binding names and setting up IDENTIFIER_TYPE_VALUEs. */ set_class_shadows (previous_class_values); for (item = previous_class_values; item; item = TREE_CHAIN (item)) { tree id = TREE_PURPOSE (item); tree decl = TREE_TYPE (item); push_class_binding (id, decl); if (TREE_CODE (decl) == TYPE_DECL) set_identifier_type_value (id, TREE_TYPE (decl)); } unuse_fields (type); } storetags (CLASSTYPE_TAGS (type)); } } /* When we exit a toplevel class scope, we save the IDENTIFIER_CLASS_VALUEs so that we can restore them quickly if we reenter the class. Here, we've entered some other class, so we must invalidate our cache. */ void invalidate_class_lookup_cache () { tree t; /* This code can be seen as a cache miss. When we've cached a class' scope's bindings and we can't use them, we need to reset them. This is it! */ for (t = previous_class_values; t; t = TREE_CHAIN (t)) IDENTIFIER_CLASS_VALUE (TREE_PURPOSE (t)) = NULL_TREE; previous_class_type = NULL_TREE; } /* Get out of the current class scope. If we were in a class scope previously, that is the one popped to. */ void popclass () { poplevel_class (); /* Since poplevel_class does the popping of class decls nowadays, this really only frees the obstack used for these decls. */ pop_class_decls (); current_class_depth--; current_class_name = current_class_stack[current_class_depth].name; current_class_type = current_class_stack[current_class_depth].type; current_access_specifier = current_class_stack[current_class_depth].access; if (current_class_stack[current_class_depth].names_used) splay_tree_delete (current_class_stack[current_class_depth].names_used); } /* Returns 1 if current_class_type is either T or a nested type of T. We start looking from 1 because entry 0 is from global scope, and has no type. */ int currently_open_class (t) tree t; { int i; if (t == current_class_type) return 1; for (i = 1; i < current_class_depth; ++i) if (current_class_stack [i].type == t) return 1; return 0; } /* If either current_class_type or one of its enclosing classes are derived from T, return the appropriate type. Used to determine how we found something via unqualified lookup. */ tree currently_open_derived_class (t) tree t; { int i; if (DERIVED_FROM_P (t, current_class_type)) return current_class_type; for (i = current_class_depth - 1; i > 0; --i) if (DERIVED_FROM_P (t, current_class_stack[i].type)) return current_class_stack[i].type; return NULL_TREE; } /* When entering a class scope, all enclosing class scopes' names with static meaning (static variables, static functions, types and enumerators) have to be visible. This recursive function calls pushclass for all enclosing class contexts until global or a local scope is reached. TYPE is the enclosed class and MODIFY is equivalent with the pushclass formal of the same name. */ void push_nested_class (type, modify) tree type; int modify; { tree context; /* A namespace might be passed in error cases, like A::B:C. */ if (type == NULL_TREE || type == error_mark_node || TREE_CODE (type) == NAMESPACE_DECL || ! IS_AGGR_TYPE (type) || TREE_CODE (type) == TEMPLATE_TYPE_PARM || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM) return; context = DECL_CONTEXT (TYPE_MAIN_DECL (type)); if (context && CLASS_TYPE_P (context)) push_nested_class (context, 2); pushclass (type, modify); } /* Undoes a push_nested_class call. MODIFY is passed on to popclass. */ void pop_nested_class () { tree context = DECL_CONTEXT (TYPE_MAIN_DECL (current_class_type)); popclass (); if (context && CLASS_TYPE_P (context)) pop_nested_class (); } /* Set global variables CURRENT_LANG_NAME to appropriate value so that behavior of name-mangling machinery is correct. */ void push_lang_context (name) tree name; { *current_lang_stack++ = current_lang_name; if (current_lang_stack - &VARRAY_TREE (current_lang_base, 0) >= (ptrdiff_t) VARRAY_SIZE (current_lang_base)) { size_t old_size = VARRAY_SIZE (current_lang_base); VARRAY_GROW (current_lang_base, old_size + 10); current_lang_stack = &VARRAY_TREE (current_lang_base, old_size); } if (name == lang_name_cplusplus) { current_lang_name = name; } else if (name == lang_name_java) { current_lang_name = name; /* DECL_IGNORED_P is initially set for these types, to avoid clutter. (See record_builtin_java_type in decl.c.) However, that causes incorrect debug entries if these types are actually used. So we re-enable debug output after extern "Java". */ DECL_IGNORED_P (TYPE_NAME (java_byte_type_node)) = 0; DECL_IGNORED_P (TYPE_NAME (java_short_type_node)) = 0; DECL_IGNORED_P (TYPE_NAME (java_int_type_node)) = 0; DECL_IGNORED_P (TYPE_NAME (java_long_type_node)) = 0; DECL_IGNORED_P (TYPE_NAME (java_float_type_node)) = 0; DECL_IGNORED_P (TYPE_NAME (java_double_type_node)) = 0; DECL_IGNORED_P (TYPE_NAME (java_char_type_node)) = 0; DECL_IGNORED_P (TYPE_NAME (java_boolean_type_node)) = 0; } else if (name == lang_name_c) { current_lang_name = name; } else error ("language string `\"%s\"' not recognized", IDENTIFIER_POINTER (name)); } /* Get out of the current language scope. */ void pop_lang_context () { /* Clear the current entry so that garbage collector won't hold on to it. */ *current_lang_stack = NULL_TREE; current_lang_name = *--current_lang_stack; } /* Type instantiation routines. */ /* Given an OVERLOAD and a TARGET_TYPE, return the function that matches the TARGET_TYPE. If there is no satisfactory match, return error_mark_node, and issue an error message if COMPLAIN is non-zero. Permit pointers to member function if PTRMEM is non-zero. If TEMPLATE_ONLY, the name of the overloaded function was a template-id, and EXPLICIT_TARGS are the explicitly provided template arguments. */ static tree resolve_address_of_overloaded_function (target_type, overload, complain, ptrmem, template_only, explicit_targs) tree target_type; tree overload; int complain; int ptrmem; int template_only; tree explicit_targs; { /* Here's what the standard says: [over.over] If the name is a function template, template argument deduction is done, and if the argument deduction succeeds, the deduced arguments are used to generate a single template function, which is added to the set of overloaded functions considered. Non-member functions and static member functions match targets of type "pointer-to-function" or "reference-to-function." Nonstatic member functions match targets of type "pointer-to-member function;" the function type of the pointer to member is used to select the member function from the set of overloaded member functions. If a nonstatic member function is selected, the reference to the overloaded function name is required to have the form of a pointer to member as described in 5.3.1. If more than one function is selected, any template functions in the set are eliminated if the set also contains a non-template function, and any given template function is eliminated if the set contains a second template function that is more specialized than the first according to the partial ordering rules 14.5.5.2. After such eliminations, if any, there shall remain exactly one selected function. */ int is_ptrmem = 0; int is_reference = 0; /* We store the matches in a TREE_LIST rooted here. The functions are the TREE_PURPOSE, not the TREE_VALUE, in this list, for easy interoperability with most_specialized_instantiation. */ tree matches = NULL_TREE; tree fn; /* By the time we get here, we should be seeing only real pointer-to-member types, not the internal POINTER_TYPE to METHOD_TYPE representation. */ my_friendly_assert (!(TREE_CODE (target_type) == POINTER_TYPE && (TREE_CODE (TREE_TYPE (target_type)) == METHOD_TYPE)), 0); if (TREE_CODE (overload) == COMPONENT_REF) overload = TREE_OPERAND (overload, 1); /* Check that the TARGET_TYPE is reasonable. */ if (TYPE_PTRFN_P (target_type)) /* This is OK. */ ; else if (TYPE_PTRMEMFUNC_P (target_type)) /* This is OK, too. */ is_ptrmem = 1; else if (TREE_CODE (target_type) == FUNCTION_TYPE) { /* This is OK, too. This comes from a conversion to reference type. */ target_type = build_reference_type (target_type); is_reference = 1; } else { if (complain) cp_error("cannot resolve overloaded function `%D' based on conversion to type `%T'", DECL_NAME (OVL_FUNCTION (overload)), target_type); return error_mark_node; } /* If we can find a non-template function that matches, we can just use it. There's no point in generating template instantiations if we're just going to throw them out anyhow. But, of course, we can only do this when we don't *need* a template function. */ if (!template_only) { tree fns; for (fns = overload; fns; fns = OVL_CHAIN (fns)) { tree fn = OVL_FUNCTION (fns); tree fntype; if (TREE_CODE (fn) == TEMPLATE_DECL) /* We're not looking for templates just yet. */ continue; if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE) != is_ptrmem) /* We're looking for a non-static member, and this isn't one, or vice versa. */ continue; /* See if there's a match. */ fntype = TREE_TYPE (fn); if (is_ptrmem) fntype = build_ptrmemfunc_type (build_pointer_type (fntype)); else if (!is_reference) fntype = build_pointer_type (fntype); if (can_convert_arg (target_type, fntype, fn)) matches = tree_cons (fn, NULL_TREE, matches); } } /* Now, if we've already got a match (or matches), there's no need to proceed to the template functions. But, if we don't have a match we need to look at them, too. */ if (!matches) { tree target_fn_type; tree target_arg_types; tree target_ret_type; tree fns; if (is_ptrmem) target_fn_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (target_type)); else target_fn_type = TREE_TYPE (target_type); target_arg_types = TYPE_ARG_TYPES (target_fn_type); target_ret_type = TREE_TYPE (target_fn_type); for (fns = overload; fns; fns = OVL_CHAIN (fns)) { tree fn = OVL_FUNCTION (fns); tree instantiation; tree instantiation_type; tree targs; if (TREE_CODE (fn) != TEMPLATE_DECL) /* We're only looking for templates. */ continue; if ((TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE) != is_ptrmem) /* We're not looking for a non-static member, and this is one, or vice versa. */ continue; /* Try to do argument deduction. */ targs = make_tree_vec (DECL_NTPARMS (fn)); if (fn_type_unification (fn, explicit_targs, targs, target_arg_types, target_ret_type, DEDUCE_EXACT) != 0) /* Argument deduction failed. */ continue; /* Instantiate the template. */ instantiation = instantiate_template (fn, targs); if (instantiation == error_mark_node) /* Instantiation failed. */ continue; /* See if there's a match. */ instantiation_type = TREE_TYPE (instantiation); if (is_ptrmem) instantiation_type = build_ptrmemfunc_type (build_pointer_type (instantiation_type)); else if (!is_reference) instantiation_type = build_pointer_type (instantiation_type); if (can_convert_arg (target_type, instantiation_type, instantiation)) matches = tree_cons (instantiation, fn, matches); } /* Now, remove all but the most specialized of the matches. */ if (matches) { tree match = most_specialized_instantiation (matches, explicit_targs); if (match != error_mark_node) matches = tree_cons (match, NULL_TREE, NULL_TREE); } } /* Now we should have exactly one function in MATCHES. */ if (matches == NULL_TREE) { /* There were *no* matches. */ if (complain) { cp_error ("no matches converting function `%D' to type `%#T'", DECL_NAME (OVL_FUNCTION (overload)), target_type); /* print_candidates expects a chain with the functions in TREE_VALUE slots, so we cons one up here (we're losing anyway, so why be clever?). */ for (; overload; overload = OVL_NEXT (overload)) matches = tree_cons (NULL_TREE, OVL_CURRENT (overload), matches); print_candidates (matches); } return error_mark_node; } else if (TREE_CHAIN (matches)) { /* There were too many matches. */ if (complain) { tree match; cp_error ("converting overloaded function `%D' to type `%#T' is ambiguous", DECL_NAME (OVL_FUNCTION (overload)), target_type); /* Since print_candidates expects the functions in the TREE_VALUE slot, we flip them here. */ for (match = matches; match; match = TREE_CHAIN (match)) TREE_VALUE (match) = TREE_PURPOSE (match); print_candidates (matches); } return error_mark_node; } /* Good, exactly one match. Now, convert it to the correct type. */ fn = TREE_PURPOSE (matches); if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn) && !ptrmem && !flag_ms_extensions) { static int explained; if (!complain) return error_mark_node; cp_pedwarn ("assuming pointer to member `%D'", fn); if (!explained) { cp_pedwarn ("(a pointer to member can only be formed with `&%E')", fn); explained = 1; } } mark_used (fn); if (TYPE_PTRFN_P (target_type) || TYPE_PTRMEMFUNC_P (target_type)) return build_unary_op (ADDR_EXPR, fn, 0); else { /* The target must be a REFERENCE_TYPE. Above, build_unary_op will mark the function as addressed, but here we must do it explicitly. */ mark_addressable (fn); return fn; } } /* This function will instantiate the type of the expression given in RHS to match the type of LHSTYPE. If errors exist, then return error_mark_node. FLAGS is a bit mask. If ITF_COMPLAIN is set, then we complain on errors. If we are not complaining, never modify rhs, as overload resolution wants to try many possible instantiations, in the hope that at least one will work. For non-recursive calls, LHSTYPE should be a function, pointer to function, or a pointer to member function. */ tree instantiate_type (lhstype, rhs, flags) tree lhstype, rhs; enum instantiate_type_flags flags; { int complain = (flags & itf_complain); int strict = (flags & itf_no_attributes) ? COMPARE_NO_ATTRIBUTES : COMPARE_STRICT; int allow_ptrmem = flags & itf_ptrmem_ok; flags &= ~itf_ptrmem_ok; if (TREE_CODE (lhstype) == UNKNOWN_TYPE) { if (complain) error ("not enough type information"); return error_mark_node; } if (TREE_TYPE (rhs) != NULL_TREE && ! (type_unknown_p (rhs))) { if (comptypes (lhstype, TREE_TYPE (rhs), strict)) return rhs; if (complain) cp_error ("argument of type `%T' does not match `%T'", TREE_TYPE (rhs), lhstype); return error_mark_node; } /* We don't overwrite rhs if it is an overloaded function. Copying it would destroy the tree link. */ if (TREE_CODE (rhs) != OVERLOAD) rhs = copy_node (rhs); /* This should really only be used when attempting to distinguish what sort of a pointer to function we have. For now, any arithmetic operation which is not supported on pointers is rejected as an error. */ switch (TREE_CODE (rhs)) { case TYPE_EXPR: case CONVERT_EXPR: case SAVE_EXPR: case CONSTRUCTOR: case BUFFER_REF: my_friendly_abort (177); return error_mark_node; case INDIRECT_REF: case ARRAY_REF: { tree new_rhs; new_rhs = instantiate_type (build_pointer_type (lhstype), TREE_OPERAND (rhs, 0), flags); if (new_rhs == error_mark_node) return error_mark_node; TREE_TYPE (rhs) = lhstype; TREE_OPERAND (rhs, 0) = new_rhs; return rhs; } case NOP_EXPR: rhs = copy_node (TREE_OPERAND (rhs, 0)); TREE_TYPE (rhs) = unknown_type_node; return instantiate_type (lhstype, rhs, flags); case COMPONENT_REF: return instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags); case OFFSET_REF: rhs = TREE_OPERAND (rhs, 1); if (BASELINK_P (rhs)) return instantiate_type (lhstype, TREE_VALUE (rhs), flags | allow_ptrmem); /* This can happen if we are forming a pointer-to-member for a member template. */ my_friendly_assert (TREE_CODE (rhs) == TEMPLATE_ID_EXPR, 0); /* Fall through. */ case TEMPLATE_ID_EXPR: { tree fns = TREE_OPERAND (rhs, 0); tree args = TREE_OPERAND (rhs, 1); return resolve_address_of_overloaded_function (lhstype, fns, complain, allow_ptrmem, /*template_only=*/1, args); } case OVERLOAD: return resolve_address_of_overloaded_function (lhstype, rhs, complain, allow_ptrmem, /*template_only=*/0, /*explicit_targs=*/NULL_TREE); case TREE_LIST: /* Now we should have a baselink. */ my_friendly_assert (BASELINK_P (rhs), 990412); return instantiate_type (lhstype, TREE_VALUE (rhs), flags); case CALL_EXPR: /* This is too hard for now. */ my_friendly_abort (183); return error_mark_node; case PLUS_EXPR: case MINUS_EXPR: case COMPOUND_EXPR: TREE_OPERAND (rhs, 0) = instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags); if (TREE_OPERAND (rhs, 0) == error_mark_node) return error_mark_node; TREE_OPERAND (rhs, 1) = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags); if (TREE_OPERAND (rhs, 1) == error_mark_node) return error_mark_node; TREE_TYPE (rhs) = lhstype; return rhs; case MULT_EXPR: case TRUNC_DIV_EXPR: case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR: case ROUND_DIV_EXPR: case RDIV_EXPR: case TRUNC_MOD_EXPR: case FLOOR_MOD_EXPR: case CEIL_MOD_EXPR: case ROUND_MOD_EXPR: case FIX_ROUND_EXPR: case FIX_FLOOR_EXPR: case FIX_CEIL_EXPR: case FIX_TRUNC_EXPR: case FLOAT_EXPR: case NEGATE_EXPR: case ABS_EXPR: case MAX_EXPR: case MIN_EXPR: case FFS_EXPR: case BIT_AND_EXPR: case BIT_IOR_EXPR: case BIT_XOR_EXPR: case LSHIFT_EXPR: case RSHIFT_EXPR: case LROTATE_EXPR: case RROTATE_EXPR: case PREINCREMENT_EXPR: case PREDECREMENT_EXPR: case POSTINCREMENT_EXPR: case POSTDECREMENT_EXPR: if (complain) error ("invalid operation on uninstantiated type"); return error_mark_node; case TRUTH_AND_EXPR: case TRUTH_OR_EXPR: case TRUTH_XOR_EXPR: case LT_EXPR: case LE_EXPR: case GT_EXPR: case GE_EXPR: case EQ_EXPR: case NE_EXPR: case TRUTH_ANDIF_EXPR: case TRUTH_ORIF_EXPR: case TRUTH_NOT_EXPR: if (complain) error ("not enough type information"); return error_mark_node; case COND_EXPR: if (type_unknown_p (TREE_OPERAND (rhs, 0))) { if (complain) error ("not enough type information"); return error_mark_node; } TREE_OPERAND (rhs, 1) = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags); if (TREE_OPERAND (rhs, 1) == error_mark_node) return error_mark_node; TREE_OPERAND (rhs, 2) = instantiate_type (lhstype, TREE_OPERAND (rhs, 2), flags); if (TREE_OPERAND (rhs, 2) == error_mark_node) return error_mark_node; TREE_TYPE (rhs) = lhstype; return rhs; case MODIFY_EXPR: TREE_OPERAND (rhs, 1) = instantiate_type (lhstype, TREE_OPERAND (rhs, 1), flags); if (TREE_OPERAND (rhs, 1) == error_mark_node) return error_mark_node; TREE_TYPE (rhs) = lhstype; return rhs; case ADDR_EXPR: { if (PTRMEM_OK_P (rhs)) flags |= itf_ptrmem_ok; return instantiate_type (lhstype, TREE_OPERAND (rhs, 0), flags); } case ENTRY_VALUE_EXPR: my_friendly_abort (184); return error_mark_node; case ERROR_MARK: return error_mark_node; default: my_friendly_abort (185); return error_mark_node; } } /* Return the name of the virtual function pointer field (as an IDENTIFIER_NODE) for the given TYPE. Note that this may have to look back through base types to find the ultimate field name. (For single inheritance, these could all be the same name. Who knows for multiple inheritance). */ static tree get_vfield_name (type) tree type; { tree binfo = TYPE_BINFO (type); char *buf; while (BINFO_BASETYPES (binfo) && TYPE_CONTAINS_VPTR_P (BINFO_TYPE (BINFO_BASETYPE (binfo, 0))) && ! TREE_VIA_VIRTUAL (BINFO_BASETYPE (binfo, 0))) binfo = BINFO_BASETYPE (binfo, 0); type = BINFO_TYPE (binfo); buf = (char *) alloca (sizeof (VFIELD_NAME_FORMAT) + TYPE_NAME_LENGTH (type) + 2); sprintf (buf, VFIELD_NAME_FORMAT, TYPE_NAME_STRING (type)); return get_identifier (buf); } void print_class_statistics () { #ifdef GATHER_STATISTICS fprintf (stderr, "convert_harshness = %d\n", n_convert_harshness); fprintf (stderr, "compute_conversion_costs = %d\n", n_compute_conversion_costs); fprintf (stderr, "build_method_call = %d (inner = %d)\n", n_build_method_call, n_inner_fields_searched); if (n_vtables) { fprintf (stderr, "vtables = %d; vtable searches = %d\n", n_vtables, n_vtable_searches); fprintf (stderr, "vtable entries = %d; vtable elems = %d\n", n_vtable_entries, n_vtable_elems); } #endif } /* Build a dummy reference to ourselves so Derived::Base (and A::A) works, according to [class]: The class-name is also inserted into the scope of the class itself. For purposes of access checking, the inserted class name is treated as if it were a public member name. */ void build_self_reference () { tree name = constructor_name (current_class_type); tree value = build_lang_decl (TYPE_DECL, name, current_class_type); tree saved_cas; DECL_NONLOCAL (value) = 1; DECL_CONTEXT (value) = current_class_type; DECL_ARTIFICIAL (value) = 1; if (processing_template_decl) value = push_template_decl (value); saved_cas = current_access_specifier; current_access_specifier = access_public_node; finish_member_declaration (value); current_access_specifier = saved_cas; } /* Returns 1 if TYPE contains only padding bytes. */ int is_empty_class (type) tree type; { tree t; if (type == error_mark_node) return 0; if (! IS_AGGR_TYPE (type)) return 0; if (flag_new_abi) return integer_zerop (CLASSTYPE_SIZE (type)); if (TYPE_BINFO_BASETYPES (type)) return 0; t = TYPE_FIELDS (type); while (t && TREE_CODE (t) != FIELD_DECL) t = TREE_CHAIN (t); return (t == NULL_TREE); } /* Find the enclosing class of the given NODE. NODE can be a *_DECL or a *_TYPE node. NODE can also be a local class. */ tree get_enclosing_class (type) tree type; { tree node = type; while (node && TREE_CODE (node) != NAMESPACE_DECL) { switch (TREE_CODE_CLASS (TREE_CODE (node))) { case 'd': node = DECL_CONTEXT (node); break; case 't': if (node != type) return node; node = TYPE_CONTEXT (node); break; default: my_friendly_abort (0); } } return NULL_TREE; } /* Return 1 if TYPE or one of its enclosing classes is derived from BASE. */ int is_base_of_enclosing_class (base, type) tree base, type; { while (type) { if (get_binfo (base, type, 0)) return 1; type = get_enclosing_class (type); } return 0; } /* Note that NAME was looked up while the current class was being defined and that the result of that lookup was DECL. */ void maybe_note_name_used_in_class (name, decl) tree name; tree decl; { splay_tree names_used; /* If we're not defining a class, there's nothing to do. */ if (!current_class_type || !TYPE_BEING_DEFINED (current_class_type)) return; /* If there's already a binding for this NAME, then we don't have anything to worry about. */ if (IDENTIFIER_CLASS_VALUE (name)) return; if (!current_class_stack[current_class_depth - 1].names_used) current_class_stack[current_class_depth - 1].names_used = splay_tree_new (splay_tree_compare_pointers, 0, 0); names_used = current_class_stack[current_class_depth - 1].names_used; splay_tree_insert (names_used, (splay_tree_key) name, (splay_tree_value) decl); } /* Note that NAME was declared (as DECL) in the current class. Check to see that the declaration is legal. */ void note_name_declared_in_class (name, decl) tree name; tree decl; { splay_tree names_used; splay_tree_node n; /* Look to see if we ever used this name. */ names_used = current_class_stack[current_class_depth - 1].names_used; if (!names_used) return; n = splay_tree_lookup (names_used, (splay_tree_key) name); if (n) { /* [basic.scope.class] A name N used in a class S shall refer to the same declaration in its context and when re-evaluated in the completed scope of S. */ cp_error ("declaration of `%#D'", decl); cp_error_at ("changes meaning of `%s' from `%+#D'", IDENTIFIER_POINTER (DECL_NAME (OVL_CURRENT (decl))), (tree) n->value); } } /* Returns the VAR_DECL for the complete vtable associated with BINFO. (Under the new ABI, secondary vtables are merged with primary vtables; this function will return the VAR_DECL for the primary vtable.) */ tree get_vtbl_decl_for_binfo (binfo) tree binfo; { tree decl; decl = BINFO_VTABLE (binfo); if (decl && TREE_CODE (decl) == PLUS_EXPR) { my_friendly_assert (TREE_CODE (TREE_OPERAND (decl, 0)) == ADDR_EXPR, 2000403); decl = TREE_OPERAND (TREE_OPERAND (decl, 0), 0); } if (decl) my_friendly_assert (TREE_CODE (decl) == VAR_DECL, 20000403); return decl; } /* Called from get_primary_binfo via dfs_walk. */ static tree dfs_get_primary_binfo (binfo, data) tree binfo; void *data; { tree primary_base = (tree) data; if (TREE_VIA_VIRTUAL (binfo) && same_type_p (TREE_TYPE (binfo), TREE_TYPE (primary_base))) return binfo; return NULL_TREE; } /* Returns the binfo for the primary base of BINFO. Note that in a complex hierarchy the resulting BINFO may not actually *be* primary. In particular if the resulting BINFO is a virtual base, and it occurs elsewhere in the hierarchy, then this occurrence may not actually be a primary base in the complete object. Check BINFO_PRIMARY_MARKED_P to be sure. */ tree get_primary_binfo (binfo) tree binfo; { tree primary_base; tree result; primary_base = CLASSTYPE_PRIMARY_BINFO (BINFO_TYPE (binfo)); if (!primary_base) return NULL_TREE; /* A non-virtual primary base is always a direct base, and easy to find. */ if (!TREE_VIA_VIRTUAL (primary_base)) { int i; /* Scan the direct basetypes until we find a base with the same type as the primary base. */ for (i = 0; i < BINFO_N_BASETYPES (binfo); ++i) { tree base_binfo = BINFO_BASETYPE (binfo, i); if (same_type_p (BINFO_TYPE (base_binfo), BINFO_TYPE (primary_base))) return base_binfo; } /* We should always find the primary base. */ my_friendly_abort (20000729); } /* For a primary virtual base, we have to scan the entire hierarchy rooted at BINFO; the virtual base could be an indirect virtual base. */ result = dfs_walk (binfo, dfs_get_primary_binfo, NULL, primary_base); my_friendly_assert (result != NULL_TREE, 20000730); return result; } /* Dump the offsets of all the bases rooted at BINFO (in the hierarchy dominated by T) to stderr. INDENT should be zero when called from the top level; it is incremented recursively. */ static void dump_class_hierarchy_r (t, binfo, indent) tree t; tree binfo; int indent; { int i; fprintf (stderr, "%*s0x%lx (%s) ", indent, "", (unsigned long) binfo, type_as_string (binfo, TFF_PLAIN_IDENTIFIER)); fprintf (stderr, HOST_WIDE_INT_PRINT_DEC, tree_low_cst (BINFO_OFFSET (binfo), 0)); if (TREE_VIA_VIRTUAL (binfo)) fprintf (stderr, " virtual"); if (BINFO_PRIMARY_MARKED_P (binfo) || (TREE_VIA_VIRTUAL (binfo) && BINFO_PRIMARY_MARKED_P (binfo_for_vbase (BINFO_TYPE (binfo), t)))) fprintf (stderr, " primary"); fprintf (stderr, "\n"); for (i = 0; i < BINFO_N_BASETYPES (binfo); ++i) dump_class_hierarchy_r (t, BINFO_BASETYPE (binfo, i), indent + 2); } /* Dump the BINFO hierarchy for T. */ void dump_class_hierarchy (t) tree t; { dump_class_hierarchy_r (t, TYPE_BINFO (t), 0); } /* Virtual function table initialization. */ /* Create all the necessary vtables for T and its base classes. */ static void finish_vtbls (t) tree t; { if (merge_primary_and_secondary_vtables_p ()) { tree list; tree vbase; /* Under the new ABI, we lay out the primary and secondary vtables in one contiguous vtable. The primary vtable is first, followed by the non-virtual secondary vtables in inheritance graph order. */ list = build_tree_list (TYPE_BINFO_VTABLE (t), NULL_TREE); accumulate_vtbl_inits (TYPE_BINFO (t), TYPE_BINFO (t), TYPE_BINFO (t), t, list); /* Then come the virtual bases, also in inheritance graph order. */ for (vbase = TYPE_BINFO (t); vbase; vbase = TREE_CHAIN (vbase)) { if (!TREE_VIA_VIRTUAL (vbase)) continue; accumulate_vtbl_inits (vbase, vbase, TYPE_BINFO (t), t, list); } if (TYPE_BINFO_VTABLE (t)) initialize_vtable (TYPE_BINFO (t), TREE_VALUE (list)); } else { dfs_walk (TYPE_BINFO (t), dfs_finish_vtbls, dfs_unmarked_real_bases_queue_p, t); dfs_walk (TYPE_BINFO (t), dfs_unmark, dfs_marked_real_bases_queue_p, t); } } /* Called from finish_vtbls via dfs_walk. */ static tree dfs_finish_vtbls (binfo, data) tree binfo; void *data; { tree t = (tree) data; if (BINFO_NEW_VTABLE_MARKED (binfo, t)) initialize_vtable (binfo, build_vtbl_initializer (binfo, binfo, t, TYPE_BINFO (t), NULL)); SET_BINFO_MARKED (binfo); return NULL_TREE; } /* Initialize the vtable for BINFO with the INITS. */ static void initialize_vtable (binfo, inits) tree binfo; tree inits; { tree decl; layout_vtable_decl (binfo, list_length (inits)); decl = get_vtbl_decl_for_binfo (binfo); initialize_array (decl, inits); } /* Initialize DECL (a declaration for a namespace-scope array) with the INITS. */ static void initialize_array (decl, inits) tree decl; tree inits; { tree context; context = DECL_CONTEXT (decl); DECL_CONTEXT (decl) = NULL_TREE; DECL_INITIAL (decl) = build_nt (CONSTRUCTOR, NULL_TREE, inits); cp_finish_decl (decl, DECL_INITIAL (decl), NULL_TREE, 0); DECL_CONTEXT (decl) = context; } /* Build the VTT (virtual table table) for T. */ static void build_vtt (t) tree t; { tree inits; tree type; tree vtt; tree index; /* Under the old ABI, we don't use VTTs. */ if (!flag_new_abi) return; /* Build up the initializers for the VTT. */ inits = NULL_TREE; index = size_zero_node; build_vtt_inits (TYPE_BINFO (t), t, /*virtual_vtts_p=*/1, &inits, &index); /* If we didn't need a VTT, we're done. */ if (!inits) return; /* Figure out the type of the VTT. */ type = build_index_type (size_int (list_length (inits))); type = build_cplus_array_type (const_ptr_type_node, type); /* Now, build the VTT object itself. */ vtt = build_vtable (t, get_vtt_name (t), type); pushdecl_top_level (vtt); initialize_array (vtt, inits); } /* The type corresponding to BINFO is a base class of T, but BINFO is in the base class hierarchy of a class derived from T. Return the base, in T's hierarchy, that corresponds to BINFO. */ static tree get_matching_base (binfo, t) tree binfo; tree t; { tree derived; int i; if (same_type_p (BINFO_TYPE (binfo), t)) return binfo; if (TREE_VIA_VIRTUAL (binfo)) return binfo_for_vbase (BINFO_TYPE (binfo), t); derived = get_matching_base (BINFO_INHERITANCE_CHAIN (binfo), t); for (i = 0; i < BINFO_N_BASETYPES (derived); ++i) if (same_type_p (BINFO_TYPE (BINFO_BASETYPE (derived, i)), BINFO_TYPE (binfo))) return BINFO_BASETYPE (derived, i); my_friendly_abort (20000628); return NULL_TREE; } /* Recursively build the VTT-initializer for BINFO (which is in the hierarchy dominated by T). If VIRTUAL_VTTS_P is non-zero, then sub-VTTs for virtual bases are included. INITS points to the end of the initializer list to date. INDEX is the VTT index where the next element will be placed. */ static tree * build_vtt_inits (binfo, t, virtual_vtts_p, inits, index) tree binfo; tree t; int virtual_vtts_p; tree *inits; tree *index; { int i; tree b; tree init; tree secondary_vptrs; int ctor_vtbl_p; /* We only need VTTs for subobjects with virtual bases. */ if (!TYPE_USES_VIRTUAL_BASECLASSES (BINFO_TYPE (binfo))) return inits; /* We need to use a construction vtable if this is not the primary VTT. */ ctor_vtbl_p = !same_type_p (TREE_TYPE (binfo), t); if (ctor_vtbl_p) { build_ctor_vtbl_group (binfo, t); /* Record the offset in the VTT where this sub-VTT can be found. */ BINFO_SUBVTT_INDEX (binfo) = *index; } /* Add the address of the primary vtable for the complete object. */ init = BINFO_VTABLE (binfo); if (TREE_CODE (init) == TREE_LIST) init = TREE_VALUE (init); *inits = build_tree_list (NULL_TREE, init); inits = &TREE_CHAIN (*inits); BINFO_VPTR_INDEX (binfo) = *index; *index = size_binop (PLUS_EXPR, *index, TYPE_SIZE_UNIT (ptr_type_node)); /* Recursively add the secondary VTTs for non-virtual bases. */ for (i = 0; i < BINFO_N_BASETYPES (binfo); ++i) { b = BINFO_BASETYPE (binfo, i); if (!TREE_VIA_VIRTUAL (b)) inits = build_vtt_inits (BINFO_BASETYPE (binfo, i), t, /*virtuals_vtts_p=*/0, inits, index); } /* Add secondary virtual pointers for all subobjects of BINFO with either virtual bases or virtual functions overridden along a virtual path between the declaration and D, except subobjects that are non-virtual primary bases. */ secondary_vptrs = tree_cons (t, NULL_TREE, BINFO_TYPE (binfo)); TREE_TYPE (secondary_vptrs) = *index; dfs_walk_real (binfo, dfs_build_secondary_vptr_vtt_inits, NULL, dfs_unmarked_real_bases_queue_p, secondary_vptrs); dfs_walk (binfo, dfs_unmark, dfs_marked_real_bases_queue_p, t); *index = TREE_TYPE (secondary_vptrs); /* The secondary vptrs come back in reverse order. After we reverse them, and add the INITS, the last init will be the first element of the chain. */ secondary_vptrs = TREE_VALUE (secondary_vptrs); if (secondary_vptrs) { *inits = nreverse (secondary_vptrs); inits = &TREE_CHAIN (secondary_vptrs); my_friendly_assert (*inits == NULL_TREE, 20000517); } /* Add the secondary VTTs for virtual bases. */ if (virtual_vtts_p) for (b = TYPE_BINFO (BINFO_TYPE (binfo)); b; b = TREE_CHAIN (b)) { tree vbase; if (!TREE_VIA_VIRTUAL (b)) continue; vbase = binfo_for_vbase (BINFO_TYPE (b), t); inits = build_vtt_inits (vbase, t, /*virtual_vtts_p=*/0, inits, index); } dfs_walk (binfo, dfs_fixup_binfo_vtbls, dfs_unmarked_real_bases_queue_p, build_tree_list (t, binfo)); return inits; } /* Called from build_vtt_inits via dfs_walk. */ static tree dfs_build_secondary_vptr_vtt_inits (binfo, data) tree binfo; void *data; { tree l; tree t; tree init; tree index; l = (tree) data; t = TREE_CHAIN (l); SET_BINFO_MARKED (binfo); /* We don't care about bases that don't have vtables. */ if (!TYPE_VFIELD (BINFO_TYPE (binfo))) return NULL_TREE; /* We're only interested in proper subobjects of T. */ if (same_type_p (BINFO_TYPE (binfo), t)) return NULL_TREE; /* We're not interested in non-virtual primary bases. */ if (!TREE_VIA_VIRTUAL (binfo) && BINFO_PRIMARY_MARKED_P (binfo)) return NULL_TREE; /* If BINFO doesn't have virtual bases, then we have to look to see whether or not any virtual functions were overidden along a virtual path. The point is that given: struct V { virtual void f(); int i; }; struct C : public virtual V { void f (); }; when we constrct C we need a secondary vptr for V-in-C because we don't know what the vcall offset for `f' should be. If `V' ends up in a different place in the complete object, then we'll need a different vcall offset than that present in the normal V-in-C vtable. */ if (!TYPE_USES_VIRTUAL_BASECLASSES (BINFO_TYPE (binfo)) && !BINFO_OVERRIDE_ALONG_VIRTUAL_PATH_P (get_matching_base (binfo, t))) return NULL_TREE; /* Record the index where this secondary vptr can be found. */ index = TREE_TYPE (l); BINFO_VPTR_INDEX (binfo) = index; TREE_TYPE (l) = size_binop (PLUS_EXPR, index, TYPE_SIZE_UNIT (ptr_type_node)); /* Add the initializer for the secondary vptr itself. */ init = BINFO_VTABLE (binfo); if (TREE_CODE (init) == TREE_LIST) init = TREE_VALUE (init); TREE_VALUE (l) = tree_cons (NULL_TREE, init, TREE_VALUE (l)); return NULL_TREE; } /* Called from build_vtt_inits via dfs_walk. */ static tree dfs_fixup_binfo_vtbls (binfo, data) tree binfo; void *data; { CLEAR_BINFO_MARKED (binfo); /* We don't care about bases that don't have vtables. */ if (!TYPE_VFIELD (BINFO_TYPE (binfo))) return NULL_TREE; /* If we scribbled the construction vtable vptr into BINFO, clear it out now. */ if (TREE_CODE (BINFO_VTABLE (binfo)) == TREE_LIST && (TREE_PURPOSE (BINFO_VTABLE (binfo)) == TREE_VALUE ((tree) data))) BINFO_VTABLE (binfo) = TREE_CHAIN (BINFO_VTABLE (binfo)); return NULL_TREE; } /* Build the construction vtable group for BINFO which is in the hierarchy dominated by T. */ static void build_ctor_vtbl_group (binfo, t) tree binfo; tree t; { tree list; tree type; tree vtbl; tree inits; tree id; tree vbase; /* See if we've already create this construction vtable group. */ if (flag_new_abi) id = mangle_ctor_vtbl_for_type (t, binfo); else id = get_ctor_vtbl_name (t, binfo); if (IDENTIFIER_GLOBAL_VALUE (id)) return; /* Build a version of VTBL (with the wrong type) for use in constructing the addresses of secondary vtables in the construction vtable group. */ vtbl = build_vtable (t, id, ptr_type_node); list = build_tree_list (vtbl, NULL_TREE); accumulate_vtbl_inits (binfo, TYPE_BINFO (TREE_TYPE (binfo)), binfo, t, list); for (vbase = TYPE_BINFO (TREE_TYPE (binfo)); vbase; vbase = TREE_CHAIN (vbase)) { tree b; if (!TREE_VIA_VIRTUAL (vbase)) continue; b = binfo_for_vbase (BINFO_TYPE (vbase), t); accumulate_vtbl_inits (b, vbase, binfo, t, list); } inits = TREE_VALUE (list); /* Figure out the type of the construction vtable. */ type = build_index_type (size_int (list_length (inits))); type = build_cplus_array_type (vtable_entry_type, type); TREE_TYPE (vtbl) = type; /* Initialize the construction vtable. */ pushdecl_top_level (vtbl); initialize_array (vtbl, inits); } /* Add the vtbl initializers for BINFO (and its non-primary, non-virtual bases) to the list of INITS. BINFO is in the hierarchy dominated by T. ORIG_BINFO must have the same type as BINFO, but may be different from BINFO if we are building a construction vtable. RTTI_BINFO gives the object that should be used as the complete object for BINFO. */ static void accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, t, inits) tree binfo; tree orig_binfo; tree rtti_binfo; tree t; tree inits; { int i; int ctor_vtbl_p; my_friendly_assert (same_type_p (BINFO_TYPE (binfo), BINFO_TYPE (orig_binfo)), 20000517); /* This is a construction vtable if the RTTI type is not the most derived type in the hierarchy. */ ctor_vtbl_p = !same_type_p (BINFO_TYPE (rtti_binfo), t); /* If we're building a construction vtable, we're not interested in subobjects that don't require construction vtables. */ if (ctor_vtbl_p && !TYPE_USES_VIRTUAL_BASECLASSES (BINFO_TYPE (binfo)) && !(BINFO_OVERRIDE_ALONG_VIRTUAL_PATH_P (get_matching_base (binfo, BINFO_TYPE (rtti_binfo))))) return; /* Build the initializers for the BINFO-in-T vtable. */ TREE_VALUE (inits) = chainon (TREE_VALUE (inits), dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, t, inits)); /* Walk the BINFO and its bases. We walk in preorder so that as we initialize each vtable we can figure out at what offset the secondary vtable lies from the primary vtable. We can't use dfs_walk here because we need to iterate through bases of BINFO and RTTI_BINFO simultaneously. */ for (i = 0; i < BINFO_N_BASETYPES (binfo); ++i) { tree base_binfo; base_binfo = BINFO_BASETYPE (binfo, i); /* Skip virtual bases. */ if (TREE_VIA_VIRTUAL (base_binfo)) continue; accumulate_vtbl_inits (base_binfo, BINFO_BASETYPE (orig_binfo, i), rtti_binfo, t, inits); } } /* Called from finish_vtbls via dfs_walk when using the new ABI. Accumulates the vtable initializers for all of the vtables into TREE_VALUE (DATA). Returns the initializers for the BINFO vtable. */ static tree dfs_accumulate_vtbl_inits (binfo, orig_binfo, rtti_binfo, t, l) tree binfo; tree orig_binfo; tree rtti_binfo; tree t; tree l; { tree inits = NULL_TREE; if (BINFO_NEW_VTABLE_MARKED (orig_binfo, t)) { tree vtbl; tree index; int non_fn_entries; /* Compute the initializer for this vtable. */ inits = build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo, &non_fn_entries); /* Figure out the position to which the VPTR should point. */ vtbl = TREE_PURPOSE (l); vtbl = build1 (ADDR_EXPR, vtbl_ptr_type_node, vtbl); index = size_binop (PLUS_EXPR, size_int (non_fn_entries), size_int (list_length (TREE_VALUE (l)))); index = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (vtable_entry_type), index); vtbl = build (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, index); TREE_CONSTANT (vtbl) = 1; /* For an ordinary vtable, set BINFO_VTABLE. */ if (same_type_p (BINFO_TYPE (rtti_binfo), t)) BINFO_VTABLE (binfo) = vtbl; /* For a construction vtable, we can't overwrite BINFO_VTABLE. So, we make a TREE_LIST. Later, dfs_fixup_binfo_vtbls will straighten this out. */ else BINFO_VTABLE (binfo) = tree_cons (rtti_binfo, vtbl, BINFO_VTABLE (binfo)); } return inits; } /* Construct the initializer for BINFOs virtual function table. BINFO is part of the hierarchy dominated by T. If we're building a construction vtable, the ORIG_BINFO is the binfo we should use to find the actual function pointers to put in the vtable. Otherwise, ORIG_BINFO should be the same as BINFO. The RTTI_BINFO is the BINFO that should be indicated by the RTTI information in the vtable; it will be a base class of T, rather than T itself, if we are building a construction vtable. The value returned is a TREE_LIST suitable for wrapping in a CONSTRUCTOR to use as the DECL_INITIAL for a vtable. If NON_FN_ENTRIES_P is not NULL, *NON_FN_ENTRIES_P is set to the number of non-function entries in the vtable. It might seem that this function should never be called with a BINFO for which BINFO_PRIMARY_MARKED_P holds, the vtable for such a base is always subsumed by a derived class vtable. However, when we are building construction vtables we do build vtables for primary bases; we need these while the primary base is being constructed. */ static tree build_vtbl_initializer (binfo, orig_binfo, t, rtti_binfo, non_fn_entries_p) tree binfo; tree orig_binfo; tree t; tree rtti_binfo; int *non_fn_entries_p; { tree v; tree vfun_inits; tree vbase; vtbl_init_data vid; /* Initialize VID. */ bzero (&vid, sizeof (vid)); vid.binfo = binfo; vid.derived = t; vid.last_init = &vid.inits; vid.primary_vtbl_p = (binfo == TYPE_BINFO (t)); vid.ctor_vtbl_p = !same_type_p (BINFO_TYPE (rtti_binfo), t); /* The first vbase or vcall offset is at index -3 in the vtable. */ vid.index = ssize_int (-3); /* Add entries to the vtable for RTTI. */ build_rtti_vtbl_entries (binfo, rtti_binfo, &vid); /* Create an array for keeping track of the functions we've processed. When we see multiple functions with the same signature, we share the vcall offsets. */ VARRAY_TREE_INIT (vid.fns, 32, "fns"); /* Add the vcall and vbase offset entries. */ build_vcall_and_vbase_vtbl_entries (binfo, &vid); /* Clean up. */ VARRAY_FREE (vid.fns); /* Clear BINFO_VTABLE_PAATH_MARKED; it's set by build_vbase_offset_vtbl_entries. */ for (vbase = CLASSTYPE_VBASECLASSES (t); vbase; vbase = TREE_CHAIN (vbase)) CLEAR_BINFO_VTABLE_PATH_MARKED (TREE_VALUE (vbase)); if (non_fn_entries_p) *non_fn_entries_p = list_length (vid.inits); /* Go through all the ordinary virtual functions, building up initializers. */ vfun_inits = NULL_TREE; for (v = BINFO_VIRTUALS (orig_binfo); v; v = TREE_CHAIN (v)) { tree delta; tree vcall_index; tree fn; tree pfn; tree init; /* Pull the offset for `this', and the function to call, out of the list. */ delta = BV_DELTA (v); if (BV_USE_VCALL_INDEX_P (v)) { vcall_index = BV_VCALL_INDEX (v); my_friendly_assert (vcall_index != NULL_TREE, 20000621); } else vcall_index = NULL_TREE; fn = BV_FN (v); my_friendly_assert (TREE_CODE (delta) == INTEGER_CST, 19990727); my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 19990727); /* You can't call an abstract virtual function; it's abstract. So, we replace these functions with __pure_virtual. */ if (DECL_PURE_VIRTUAL_P (fn)) fn = abort_fndecl; /* Take the address of the function, considering it to be of an appropriate generic type. */ pfn = build1 (ADDR_EXPR, vfunc_ptr_type_node, fn); /* The address of a function can't change. */ TREE_CONSTANT (pfn) = 1; /* Enter it in the vtable. */ init = build_vtable_entry (delta, vcall_index, pfn, BV_GENERATE_THUNK_WITH_VTABLE_P (v)); /* And add it to the chain of initializers. */ vfun_inits = tree_cons (NULL_TREE, init, vfun_inits); } /* The initializers for virtual functions were built up in reverse order; straighten them out now. */ vfun_inits = nreverse (vfun_inits); /* The negative offset initializers are also in reverse order. */ vid.inits = nreverse (vid.inits); /* Chain the two together. */ return chainon (vid.inits, vfun_inits); } /* Sets vid->inits to be the initializers for the vbase and vcall offsets in BINFO, which is in the hierarchy dominated by T. */ static void build_vcall_and_vbase_vtbl_entries (binfo, vid) tree binfo; vtbl_init_data *vid; { tree b; /* If this is a derived class, we must first create entries corresponding to the primary base class. */ b = get_primary_binfo (binfo); if (b) build_vcall_and_vbase_vtbl_entries (b, vid); /* Add the vbase entries for this base. */ build_vbase_offset_vtbl_entries (binfo, vid); /* Add the vcall entries for this base. */ build_vcall_offset_vtbl_entries (binfo, vid); } /* Returns the initializers for the vbase offset entries in the vtable for BINFO (which is part of the class hierarchy dominated by T), in reverse order. VBASE_OFFSET_INDEX gives the vtable index where the next vbase offset will go. */ static void build_vbase_offset_vtbl_entries (binfo, vid) tree binfo; vtbl_init_data *vid; { tree vbase; tree t; /* Under the old ABI, pointers to virtual bases are stored in each object. */ if (!vbase_offsets_in_vtable_p ()) return; /* If there are no virtual baseclasses, then there is nothing to do. */ if (!TYPE_USES_VIRTUAL_BASECLASSES (BINFO_TYPE (binfo))) return; t = vid->derived; /* Go through the virtual bases, adding the offsets. */ for (vbase = TYPE_BINFO (BINFO_TYPE (binfo)); vbase; vbase = TREE_CHAIN (vbase)) { tree b; tree delta; if (!TREE_VIA_VIRTUAL (vbase)) continue; /* Find the instance of this virtual base in the complete object. */ b = binfo_for_vbase (BINFO_TYPE (vbase), t); /* If we've already got an offset for this virtual base, we don't need another one. */ if (BINFO_VTABLE_PATH_MARKED (b)) continue; SET_BINFO_VTABLE_PATH_MARKED (b); /* Figure out where we can find this vbase offset. */ delta = size_binop (MULT_EXPR, vid->index, convert (ssizetype, TYPE_SIZE_UNIT (vtable_entry_type))); if (vid->primary_vtbl_p) BINFO_VPTR_FIELD (b) = delta; if (binfo != TYPE_BINFO (t)) { tree orig_vbase; /* Find the instance of this virtual base in the type of BINFO. */ orig_vbase = binfo_for_vbase (BINFO_TYPE (vbase), BINFO_TYPE (binfo)); /* The vbase offset had better be the same. */ if (!tree_int_cst_equal (delta, BINFO_VPTR_FIELD (orig_vbase))) my_friendly_abort (20000403); } /* The next vbase will come at a more negative offset. */ vid->index = size_binop (MINUS_EXPR, vid->index, ssize_int (1)); /* The initializer is the delta from BINFO to this virtual base. The vbase offsets go in reverse inheritance-graph order, and we are walking in inheritance graph order so these end up in the right order. */ delta = size_diffop (BINFO_OFFSET (b), BINFO_OFFSET (binfo)); *vid->last_init = build_tree_list (NULL_TREE, fold (build1 (NOP_EXPR, vtable_entry_type, delta))); vid->last_init = &TREE_CHAIN (*vid->last_init); } } /* Adds the initializers for the vcall offset entries in the vtable for BINFO (which is part of the class hierarchy dominated by T) to VID->INITS. */ static void build_vcall_offset_vtbl_entries (binfo, vid) tree binfo; vtbl_init_data *vid; { /* Under the old ABI, the adjustments to the `this' pointer were made elsewhere. */ if (!vcall_offsets_in_vtable_p ()) return; /* We only need these entries if this base is a virtual base. */ if (!TREE_VIA_VIRTUAL (binfo)) return; /* We need a vcall offset for each of the virtual functions in this vtable. For example: class A { virtual void f (); }; class B : virtual public A { }; class C: virtual public A, public B {}; Now imagine: B* b = new C; b->f(); The location of `A' is not at a fixed offset relative to `B'; the offset depends on the complete object derived from `B'. So, `B' vtable contains an entry for `f' that indicates by what amount the `this' pointer for `B' needs to be adjusted to arrive at `A'. We need entries for all the functions in our primary vtable and in our non-virtual bases vtables. */ vid->vbase = binfo; /* Now, walk through the non-virtual bases, adding vcall offsets. */ add_vcall_offset_vtbl_entries_r (binfo, vid); } /* Build vcall offsets, starting with those for BINFO. */ static void add_vcall_offset_vtbl_entries_r (binfo, vid) tree binfo; vtbl_init_data *vid; { int i; tree primary_binfo; /* Don't walk into virtual bases -- except, of course, for the virtual base for which we are building vcall offsets. */ if (TREE_VIA_VIRTUAL (binfo) && vid->vbase != binfo) return; /* If BINFO has a primary base, process it first. */ primary_binfo = get_primary_binfo (binfo); if (primary_binfo) add_vcall_offset_vtbl_entries_r (primary_binfo, vid); /* Add BINFO itself to the list. */ add_vcall_offset_vtbl_entries_1 (binfo, vid); /* Scan the non-primary bases of BINFO. */ for (i = 0; i < BINFO_N_BASETYPES (binfo); ++i) { tree base_binfo; base_binfo = BINFO_BASETYPE (binfo, i); if (base_binfo != primary_binfo) add_vcall_offset_vtbl_entries_r (base_binfo, vid); } } /* Called from build_vcall_offset_vtbl_entries via dfs_walk. */ static void add_vcall_offset_vtbl_entries_1 (binfo, vid) tree binfo; vtbl_init_data* vid; { tree derived_virtuals; tree base_virtuals; tree orig_virtuals; tree binfo_inits; /* If BINFO is a primary base, this is the least derived class of BINFO that is not a primary base. */ tree non_primary_binfo; binfo_inits = NULL_TREE; /* We might be a primary base class. Go up the inheritance hierarchy until we find the class of which we are a primary base: it is the BINFO_VIRTUALS there that we need to consider. */ non_primary_binfo = binfo; while (BINFO_INHERITANCE_CHAIN (non_primary_binfo)) { tree b; /* If we have reached a virtual base, then it must be the virtual base for which we are building vcall offsets. In turn, the virtual base must be a (possibly indirect) primary base of the class that we are initializing, or we wouldn't care about its vtable offsets. */ if (TREE_VIA_VIRTUAL (non_primary_binfo)) { non_primary_binfo = vid->binfo; break; } b = BINFO_INHERITANCE_CHAIN (non_primary_binfo); if (get_primary_binfo (b) != non_primary_binfo) break; non_primary_binfo = b; } /* Make entries for the rest of the virtuals. */ for (base_virtuals = BINFO_VIRTUALS (binfo), derived_virtuals = BINFO_VIRTUALS (non_primary_binfo), orig_virtuals = BINFO_VIRTUALS (TYPE_BINFO (BINFO_TYPE (binfo))); base_virtuals; base_virtuals = TREE_CHAIN (base_virtuals), derived_virtuals = TREE_CHAIN (derived_virtuals), orig_virtuals = TREE_CHAIN (orig_virtuals)) { tree orig_fn; tree fn; tree base; tree base_binfo; size_t i; /* Find the declaration that originally caused this function to be present. */ orig_fn = BV_FN (orig_virtuals); /* We do not need an entry if this function is declared in a virtual base (or one of its virtual bases), and not overridden in the section of the hierarchy dominated by the virtual base for which we are building vcall offsets. */ if (!same_type_p (DECL_CONTEXT (orig_fn), BINFO_TYPE (binfo))) continue; /* Find the overriding function. */ fn = BV_FN (derived_virtuals); /* If there is already an entry for a function with the same signature as FN, then we do not need a second vcall offset. Check the list of functions already present in the derived class vtable. */ for (i = 0; i < VARRAY_ACTIVE_SIZE (vid->fns); ++i) { tree derived_entry; derived_entry = VARRAY_TREE (vid->fns, i); if (same_signature_p (BV_FN (derived_entry), fn)) { BV_VCALL_INDEX (derived_virtuals) = BV_VCALL_INDEX (derived_entry); break; } } if (i != VARRAY_ACTIVE_SIZE (vid->fns)) continue; /* The FN comes from BASE. So, we must caculate the adjustment from the virtual base that derived from BINFO to BASE. */ base = DECL_CONTEXT (fn); base_binfo = get_binfo (base, vid->derived, /*protect=*/0); /* Compute the vcall offset. */ *vid->last_init = (build_tree_list (NULL_TREE, fold (build1 (NOP_EXPR, vtable_entry_type, size_diffop (BINFO_OFFSET (base_binfo), BINFO_OFFSET (vid->vbase)))))); vid->last_init = &TREE_CHAIN (*vid->last_init); /* Keep track of the vtable index where this vcall offset can be found. For a construction vtable, we already made this annotation when we build the original vtable. */ if (!vid->ctor_vtbl_p) BV_VCALL_INDEX (derived_virtuals) = vid->index; /* The next vcall offset will be found at a more negative offset. */ vid->index = size_binop (MINUS_EXPR, vid->index, ssize_int (1)); /* Keep track of this function. */ VARRAY_PUSH_TREE (vid->fns, derived_virtuals); } } /* Return vtbl initializers for the RTTI entries coresponding to the BINFO's vtable. The RTTI entries should indicate the object given by RTTI_BINFO. */ static void build_rtti_vtbl_entries (binfo, rtti_binfo, vid) tree binfo; tree rtti_binfo; vtbl_init_data *vid; { tree b; tree t; tree basetype; tree offset; tree decl; tree init; basetype = BINFO_TYPE (binfo); t = BINFO_TYPE (rtti_binfo); /* For a COM object there is no RTTI entry. */ if (CLASSTYPE_COM_INTERFACE (basetype)) return; /* To find the complete object, we will first convert to our most primary base, and then add the offset in the vtbl to that value. */ b = binfo; while (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (b))) { tree primary_base; primary_base = get_primary_binfo (b); if (!BINFO_PRIMARY_MARKED_P (primary_base)) break; b = primary_base; } offset = size_diffop (BINFO_OFFSET (rtti_binfo), BINFO_OFFSET (b)); /* The second entry is, in the case of the new ABI, the address of the typeinfo object, or, in the case of the old ABI, a function which returns a typeinfo object. */ if (new_abi_rtti_p ()) { if (flag_rtti) decl = build_unary_op (ADDR_EXPR, get_tinfo_decl (t), 0); else decl = integer_zero_node; /* Convert the declaration to a type that can be stored in the vtable. */ init = build1 (NOP_EXPR, vfunc_ptr_type_node, decl); TREE_CONSTANT (init) = 1; } else { if (flag_rtti) decl = get_tinfo_decl (t); else decl = abort_fndecl; /* Convert the declaration to a type that can be stored in the vtable. */ init = build1 (ADDR_EXPR, vfunc_ptr_type_node, decl); TREE_CONSTANT (init) = 1; init = build_vtable_entry (offset, NULL_TREE, init, /*generate_with_vtable_p=*/0); } *vid->last_init = build_tree_list (NULL_TREE, init); vid->last_init = &TREE_CHAIN (*vid->last_init); /* Add the offset-to-top entry. It comes earlier in the vtable that the the typeinfo entry. */ if (flag_vtable_thunks) { /* Convert the offset to look like a function pointer, so that we can put it in the vtable. */ init = build1 (NOP_EXPR, vfunc_ptr_type_node, offset); TREE_CONSTANT (init) = 1; *vid->last_init = build_tree_list (NULL_TREE, init); vid->last_init = &TREE_CHAIN (*vid->last_init); } } /* Build an entry in the virtual function table. DELTA is the offset for the `this' pointer. VCALL_INDEX is the vtable index containing the vcall offset; zero if none. ENTRY is the virtual function table entry itself. It's TREE_TYPE must be VFUNC_PTR_TYPE_NODE, but it may not actually be a virtual function table pointer. (For example, it might be the address of the RTTI object, under the new ABI.) */ static tree build_vtable_entry (delta, vcall_index, entry, generate_with_vtable_p) tree delta; tree vcall_index; tree entry; int generate_with_vtable_p; { if (flag_vtable_thunks) { tree fn; fn = TREE_OPERAND (entry, 0); if ((!integer_zerop (delta) || vcall_index != NULL_TREE) && fn != abort_fndecl && !DECL_TINFO_FN_P (fn)) { entry = make_thunk (entry, delta, vcall_index, generate_with_vtable_p); entry = build1 (ADDR_EXPR, vtable_entry_type, entry); TREE_READONLY (entry) = 1; TREE_CONSTANT (entry) = 1; } #ifdef GATHER_STATISTICS n_vtable_entries += 1; #endif return entry; } else { tree elems = tree_cons (NULL_TREE, delta, tree_cons (NULL_TREE, integer_zero_node, build_tree_list (NULL_TREE, entry))); tree entry = build (CONSTRUCTOR, vtable_entry_type, NULL_TREE, elems); /* We don't use vcall offsets when not using vtable thunks. */ my_friendly_assert (vcall_index == NULL_TREE, 20000125); /* DELTA used to be constructed by `size_int' and/or size_binop, which caused overflow problems when it was negative. That should be fixed now. */ if (! int_fits_type_p (delta, delta_type_node)) { if (flag_huge_objects) sorry ("object size exceeds built-in limit for virtual function table implementation"); else sorry ("object size exceeds normal limit for virtual function table implementation, recompile all source and use -fhuge-objects"); } TREE_CONSTANT (entry) = 1; TREE_STATIC (entry) = 1; TREE_READONLY (entry) = 1; #ifdef GATHER_STATISTICS n_vtable_entries += 1; #endif return entry; } }