| /* Breadth-first and depth-first routines for |
| searching multiple-inheritance lattice for GNU C++. |
| Copyright (C) 1987, 1989, 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 "obstack.h" |
| #include "flags.h" |
| #include "rtl.h" |
| #include "output.h" |
| #include "toplev.h" |
| |
| #define obstack_chunk_alloc xmalloc |
| #define obstack_chunk_free free |
| |
| #include "stack.h" |
| |
| /* Obstack used for remembering decision points of breadth-first. */ |
| |
| static struct obstack search_obstack; |
| |
| /* Methods for pushing and popping objects to and from obstacks. */ |
| |
| struct stack_level * |
| push_stack_level (obstack, tp, size) |
| struct obstack *obstack; |
| char *tp; /* Sony NewsOS 5.0 compiler doesn't like void * here. */ |
| int size; |
| { |
| struct stack_level *stack; |
| obstack_grow (obstack, tp, size); |
| stack = (struct stack_level *) ((char*)obstack_next_free (obstack) - size); |
| obstack_finish (obstack); |
| stack->obstack = obstack; |
| stack->first = (tree *) obstack_base (obstack); |
| stack->limit = obstack_room (obstack) / sizeof (tree *); |
| return stack; |
| } |
| |
| struct stack_level * |
| pop_stack_level (stack) |
| struct stack_level *stack; |
| { |
| struct stack_level *tem = stack; |
| struct obstack *obstack = tem->obstack; |
| stack = tem->prev; |
| obstack_free (obstack, tem); |
| return stack; |
| } |
| |
| #define search_level stack_level |
| static struct search_level *search_stack; |
| |
| struct vbase_info |
| { |
| /* The class dominating the hierarchy. */ |
| tree type; |
| /* A pointer to a complete object of the indicated TYPE. */ |
| tree decl_ptr; |
| tree inits; |
| }; |
| |
| static tree get_vbase_1 PARAMS ((tree, tree, unsigned int *)); |
| static tree lookup_field_1 PARAMS ((tree, tree)); |
| static int is_subobject_of_p PARAMS ((tree, tree, tree)); |
| static tree virtual_context PARAMS ((tree, tree, tree)); |
| static tree dfs_check_overlap PARAMS ((tree, void *)); |
| static tree dfs_no_overlap_yet PARAMS ((tree, void *)); |
| static int get_base_distance_recursive |
| PARAMS ((tree, int, int, int, int *, tree *, tree, |
| int, int *, int, int)); |
| static int dynamic_cast_base_recurse PARAMS ((tree, tree, int, tree *)); |
| static void expand_upcast_fixups |
| PARAMS ((tree, tree, tree, tree, tree, tree, tree *)); |
| static void fixup_virtual_upcast_offsets |
| PARAMS ((tree, tree, int, int, tree, tree, tree, tree, |
| tree *)); |
| static tree marked_pushdecls_p PARAMS ((tree, void *)); |
| static tree unmarked_pushdecls_p PARAMS ((tree, void *)); |
| static tree dfs_debug_unmarkedp PARAMS ((tree, void *)); |
| static tree dfs_debug_mark PARAMS ((tree, void *)); |
| static tree dfs_init_vbase_pointers PARAMS ((tree, void *)); |
| static tree dfs_get_vbase_types PARAMS ((tree, void *)); |
| static tree dfs_push_type_decls PARAMS ((tree, void *)); |
| static tree dfs_push_decls PARAMS ((tree, void *)); |
| static tree dfs_unuse_fields PARAMS ((tree, void *)); |
| static tree add_conversions PARAMS ((tree, void *)); |
| static int covariant_return_p PARAMS ((tree, tree)); |
| static int check_final_overrider PARAMS ((tree, tree)); |
| static int look_for_overrides_r PARAMS ((tree, tree)); |
| static struct search_level *push_search_level |
| PARAMS ((struct stack_level *, struct obstack *)); |
| static struct search_level *pop_search_level |
| PARAMS ((struct stack_level *)); |
| static tree bfs_walk |
| PARAMS ((tree, tree (*) (tree, void *), tree (*) (tree, void *), |
| void *)); |
| static tree lookup_field_queue_p PARAMS ((tree, void *)); |
| static int shared_member_p PARAMS ((tree)); |
| static tree lookup_field_r PARAMS ((tree, void *)); |
| static tree canonical_binfo PARAMS ((tree)); |
| static tree shared_marked_p PARAMS ((tree, void *)); |
| static tree shared_unmarked_p PARAMS ((tree, void *)); |
| static int dependent_base_p PARAMS ((tree)); |
| static tree dfs_accessible_queue_p PARAMS ((tree, void *)); |
| static tree dfs_accessible_p PARAMS ((tree, void *)); |
| static tree dfs_access_in_type PARAMS ((tree, void *)); |
| static access_kind access_in_type PARAMS ((tree, tree)); |
| static tree dfs_canonical_queue PARAMS ((tree, void *)); |
| static tree dfs_assert_unmarked_p PARAMS ((tree, void *)); |
| static void assert_canonical_unmarked PARAMS ((tree)); |
| static int protected_accessible_p PARAMS ((tree, tree, tree)); |
| static int friend_accessible_p PARAMS ((tree, tree, tree)); |
| static void setup_class_bindings PARAMS ((tree, int)); |
| static int template_self_reference_p PARAMS ((tree, tree)); |
| static tree get_shared_vbase_if_not_primary PARAMS ((tree, void *)); |
| static tree dfs_find_vbase_instance PARAMS ((tree, void *)); |
| static tree dfs_get_pure_virtuals PARAMS ((tree, void *)); |
| static tree dfs_build_inheritance_graph_order PARAMS ((tree, void *)); |
| static tree dfs_vtable_path_unmark PARAMS ((tree, void *)); |
| |
| /* Allocate a level of searching. */ |
| |
| static struct search_level * |
| push_search_level (stack, obstack) |
| struct stack_level *stack; |
| struct obstack *obstack; |
| { |
| struct search_level tem; |
| |
| tem.prev = stack; |
| return push_stack_level (obstack, (char *)&tem, sizeof (tem)); |
| } |
| |
| /* Discard a level of search allocation. */ |
| |
| static struct search_level * |
| pop_search_level (obstack) |
| struct stack_level *obstack; |
| { |
| register struct search_level *stack = pop_stack_level (obstack); |
| |
| return stack; |
| } |
| |
| /* Variables for gathering statistics. */ |
| #ifdef GATHER_STATISTICS |
| static int n_fields_searched; |
| static int n_calls_lookup_field, n_calls_lookup_field_1; |
| static int n_calls_lookup_fnfields, n_calls_lookup_fnfields_1; |
| static int n_calls_get_base_type; |
| static int n_outer_fields_searched; |
| static int n_contexts_saved; |
| #endif /* GATHER_STATISTICS */ |
| |
| |
| /* Get a virtual binfo that is found inside BINFO's hierarchy that is |
| the same type as the type given in PARENT. To be optimal, we want |
| the first one that is found by going through the least number of |
| virtual bases. |
| |
| This uses a clever algorithm that updates *depth when we find the vbase, |
| and cuts off other paths of search when they reach that depth. */ |
| |
| static tree |
| get_vbase_1 (parent, binfo, depth) |
| tree parent, binfo; |
| unsigned int *depth; |
| { |
| tree binfos; |
| int i, n_baselinks; |
| tree rval = NULL_TREE; |
| int virtualp = TREE_VIA_VIRTUAL (binfo) != 0; |
| |
| *depth -= virtualp; |
| if (virtualp && BINFO_TYPE (binfo) == parent) |
| { |
| *depth = 0; |
| return binfo; |
| } |
| |
| binfos = BINFO_BASETYPES (binfo); |
| n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0; |
| |
| /* Process base types. */ |
| for (i = 0; i < n_baselinks; i++) |
| { |
| tree base_binfo = TREE_VEC_ELT (binfos, i); |
| tree nrval; |
| |
| if (*depth == 0) |
| break; |
| |
| nrval = get_vbase_1 (parent, base_binfo, depth); |
| if (nrval) |
| rval = nrval; |
| } |
| *depth += virtualp; |
| return rval; |
| } |
| |
| /* Return the shortest path to vbase PARENT within BINFO, ignoring |
| access and ambiguity. */ |
| |
| tree |
| get_vbase (parent, binfo) |
| tree parent; |
| tree binfo; |
| { |
| unsigned int d = (unsigned int)-1; |
| return get_vbase_1 (parent, binfo, &d); |
| } |
| |
| /* Convert EXPR to a virtual base class of type TYPE. We know that |
| EXPR is a non-null POINTER_TYPE to RECORD_TYPE. We also know that |
| the type of what expr points to has a virtual base of type TYPE. */ |
| |
| tree |
| convert_pointer_to_vbase (type, expr) |
| tree type; |
| tree expr; |
| { |
| tree vb = get_vbase (type, TYPE_BINFO (TREE_TYPE (TREE_TYPE (expr)))); |
| return convert_pointer_to_real (vb, expr); |
| } |
| |
| /* Check whether the type given in BINFO is derived from PARENT. If |
| it isn't, return 0. If it is, but the derivation is MI-ambiguous |
| AND protect != 0, emit an error message and return error_mark_node. |
| |
| Otherwise, if TYPE is derived from PARENT, return the actual base |
| information, unless a one of the protection violations below |
| occurs, in which case emit an error message and return error_mark_node. |
| |
| If PROTECT is 1, then check if access to a public field of PARENT |
| would be private. Also check for ambiguity. */ |
| |
| tree |
| get_binfo (parent, binfo, protect) |
| register tree parent, binfo; |
| int protect; |
| { |
| tree type = NULL_TREE; |
| int dist; |
| tree rval = NULL_TREE; |
| |
| if (TREE_CODE (parent) == TREE_VEC) |
| parent = BINFO_TYPE (parent); |
| else if (! IS_AGGR_TYPE_CODE (TREE_CODE (parent))) |
| my_friendly_abort (89); |
| |
| if (TREE_CODE (binfo) == TREE_VEC) |
| type = BINFO_TYPE (binfo); |
| else if (IS_AGGR_TYPE_CODE (TREE_CODE (binfo))) |
| type = binfo; |
| else |
| my_friendly_abort (90); |
| |
| dist = get_base_distance (parent, binfo, protect, &rval); |
| |
| if (dist == -3) |
| { |
| cp_error ("fields of `%T' are inaccessible in `%T' due to private inheritance", |
| parent, type); |
| return error_mark_node; |
| } |
| else if (dist == -2 && protect) |
| { |
| cp_error ("type `%T' is ambiguous base class for type `%T'", parent, |
| type); |
| return error_mark_node; |
| } |
| |
| return rval; |
| } |
| |
| /* This is the newer depth first get_base_distance routine. */ |
| |
| static int |
| get_base_distance_recursive (binfo, depth, is_private, rval, |
| rval_private_ptr, new_binfo_ptr, parent, |
| protect, via_virtual_ptr, via_virtual, |
| current_scope_in_chain) |
| tree binfo; |
| int depth, is_private, rval; |
| int *rval_private_ptr; |
| tree *new_binfo_ptr, parent; |
| int protect, *via_virtual_ptr, via_virtual; |
| int current_scope_in_chain; |
| { |
| tree binfos; |
| int i, n_baselinks; |
| |
| if (protect == 1 |
| && !current_scope_in_chain |
| && is_friend (BINFO_TYPE (binfo), current_scope ())) |
| current_scope_in_chain = 1; |
| |
| if (BINFO_TYPE (binfo) == parent || binfo == parent) |
| { |
| int better = 0; |
| |
| if (rval == -1) |
| /* This is the first time we've found parent. */ |
| better = 1; |
| else if (tree_int_cst_equal (BINFO_OFFSET (*new_binfo_ptr), |
| BINFO_OFFSET (binfo)) |
| && *via_virtual_ptr && via_virtual) |
| { |
| /* A new path to the same vbase. If this one has better |
| access or is shorter, take it. */ |
| |
| if (protect) |
| better = *rval_private_ptr - is_private; |
| if (better == 0) |
| better = rval - depth; |
| } |
| else |
| { |
| /* Ambiguous base class. */ |
| rval = depth = -2; |
| |
| /* If we get an ambiguity between virtual and non-virtual base |
| class, return the non-virtual in case we are ignoring |
| ambiguity. */ |
| better = *via_virtual_ptr - via_virtual; |
| } |
| |
| if (better > 0) |
| { |
| rval = depth; |
| *rval_private_ptr = is_private; |
| *new_binfo_ptr = binfo; |
| *via_virtual_ptr = via_virtual; |
| } |
| |
| return rval; |
| } |
| |
| binfos = BINFO_BASETYPES (binfo); |
| n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0; |
| depth += 1; |
| |
| /* Process base types. */ |
| for (i = 0; i < n_baselinks; i++) |
| { |
| tree base_binfo = TREE_VEC_ELT (binfos, i); |
| |
| int via_private |
| = ((protect == 1 |
| && (is_private |
| || (!TREE_VIA_PUBLIC (base_binfo) |
| && !(TREE_VIA_PROTECTED (base_binfo) |
| && current_scope_in_chain) |
| && !is_friend (BINFO_TYPE (binfo), current_scope ())))) |
| || (protect > 1 |
| && (is_private || !TREE_VIA_PUBLIC (base_binfo)))); |
| |
| int this_virtual = via_virtual || TREE_VIA_VIRTUAL (base_binfo); |
| |
| rval = get_base_distance_recursive (base_binfo, depth, via_private, |
| rval, rval_private_ptr, |
| new_binfo_ptr, parent, |
| protect, via_virtual_ptr, |
| this_virtual, |
| current_scope_in_chain); |
| |
| /* If we've found a non-virtual, ambiguous base class, we don't need |
| to keep searching. */ |
| if (rval == -2 && *via_virtual_ptr == 0) |
| return rval; |
| } |
| |
| return rval; |
| } |
| |
| /* Return the number of levels between type PARENT and the type given |
| in BINFO, following the leftmost path to PARENT not found along a |
| virtual path, if there are no real PARENTs (all come from virtual |
| base classes), then follow the shortest public path to PARENT. |
| |
| Return -1 if TYPE is not derived from PARENT. |
| Return -2 if PARENT is an ambiguous base class of TYPE, and PROTECT is |
| non-negative. |
| Return -3 if PARENT is not accessible in TYPE, and PROTECT is non-zero. |
| |
| If PATH_PTR is non-NULL, then also build the list of types |
| from PARENT to TYPE, with TREE_VIA_VIRTUAL and TREE_VIA_PUBLIC |
| set. |
| |
| If PROTECT is greater than 1, ignore any special access the current |
| scope might have when determining whether PARENT is inaccessible. |
| |
| PARENT can also be a binfo, in which case that exact parent is found |
| and no other. convert_pointer_to_real uses this functionality. |
| |
| If BINFO is a binfo, its BINFO_INHERITANCE_CHAIN will be left alone. */ |
| |
| int |
| get_base_distance (parent, binfo, protect, path_ptr) |
| register tree parent, binfo; |
| int protect; |
| tree *path_ptr; |
| { |
| int rval; |
| int rval_private = 0; |
| tree type = NULL_TREE; |
| tree new_binfo = NULL_TREE; |
| int via_virtual; |
| int watch_access = protect; |
| |
| /* Should we be completing types here? */ |
| if (TREE_CODE (parent) != TREE_VEC) |
| parent = complete_type (TYPE_MAIN_VARIANT (parent)); |
| else |
| complete_type (TREE_TYPE (parent)); |
| |
| if (TREE_CODE (binfo) == TREE_VEC) |
| type = BINFO_TYPE (binfo); |
| else if (IS_AGGR_TYPE_CODE (TREE_CODE (binfo))) |
| { |
| type = complete_type (binfo); |
| binfo = TYPE_BINFO (type); |
| |
| if (path_ptr) |
| my_friendly_assert (BINFO_INHERITANCE_CHAIN (binfo) == NULL_TREE, |
| 980827); |
| } |
| else |
| my_friendly_abort (92); |
| |
| if (parent == type || parent == binfo) |
| { |
| /* If the distance is 0, then we don't really need |
| a path pointer, but we shouldn't let garbage go back. */ |
| if (path_ptr) |
| *path_ptr = binfo; |
| return 0; |
| } |
| |
| if (path_ptr && watch_access == 0) |
| watch_access = 1; |
| |
| rval = get_base_distance_recursive (binfo, 0, 0, -1, |
| &rval_private, &new_binfo, parent, |
| watch_access, &via_virtual, 0, |
| 0); |
| |
| /* Access restrictions don't count if we found an ambiguous basetype. */ |
| if (rval == -2 && protect >= 0) |
| rval_private = 0; |
| |
| if (rval && protect && rval_private) |
| return -3; |
| |
| /* If they gave us the real vbase binfo, which isn't in the main binfo |
| tree, deal with it. This happens when we are called from |
| expand_upcast_fixups. */ |
| if (rval == -1 && TREE_CODE (parent) == TREE_VEC |
| && parent == binfo_for_vbase (BINFO_TYPE (parent), type)) |
| { |
| new_binfo = parent; |
| rval = 1; |
| } |
| |
| if (path_ptr) |
| *path_ptr = new_binfo; |
| return rval; |
| } |
| |
| /* Worker function for get_dynamic_cast_base_type. */ |
| |
| static int |
| dynamic_cast_base_recurse (subtype, binfo, via_virtual, offset_ptr) |
| tree subtype; |
| tree binfo; |
| int via_virtual; |
| tree *offset_ptr; |
| { |
| tree binfos; |
| int i, n_baselinks; |
| int worst = -2; |
| |
| if (BINFO_TYPE (binfo) == subtype) |
| { |
| if (via_virtual) |
| return -1; |
| else |
| { |
| *offset_ptr = BINFO_OFFSET (binfo); |
| return 0; |
| } |
| } |
| |
| binfos = BINFO_BASETYPES (binfo); |
| n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0; |
| for (i = 0; i < n_baselinks; i++) |
| { |
| tree base_binfo = TREE_VEC_ELT (binfos, i); |
| int rval; |
| |
| if (!TREE_VIA_PUBLIC (base_binfo)) |
| continue; |
| rval = dynamic_cast_base_recurse |
| (subtype, base_binfo, |
| via_virtual || TREE_VIA_VIRTUAL (base_binfo), offset_ptr); |
| if (worst == -2) |
| worst = rval; |
| else if (rval >= 0) |
| worst = worst >= 0 ? -3 : worst; |
| else if (rval == -1) |
| worst = -1; |
| else if (rval == -3 && worst != -1) |
| worst = -3; |
| } |
| return worst; |
| } |
| |
| /* The dynamic cast runtime needs a hint about how the static SUBTYPE type |
| started from is related to the required TARGET type, in order to optimize |
| the inheritance graph search. This information is independant of the |
| current context, and ignores private paths, hence get_base_distance is |
| inappropriate. Return a TREE specifying the base offset, BOFF. |
| BOFF >= 0, there is only one public non-virtual SUBTYPE base at offset BOFF, |
| and there are no public virtual SUBTYPE bases. |
| BOFF == -1, SUBTYPE occurs as multiple public virtual or non-virtual bases. |
| BOFF == -2, SUBTYPE is not a public base. |
| BOFF == -3, SUBTYPE occurs as multiple public non-virtual bases. */ |
| |
| tree |
| get_dynamic_cast_base_type (subtype, target) |
| tree subtype; |
| tree target; |
| { |
| tree offset = NULL_TREE; |
| int boff = dynamic_cast_base_recurse (subtype, TYPE_BINFO (target), |
| 0, &offset); |
| |
| if (!boff) |
| return offset; |
| offset = build_int_2 (boff, -1); |
| TREE_TYPE (offset) = ssizetype; |
| return offset; |
| } |
| |
| /* Search for a member with name NAME in a multiple inheritance lattice |
| specified by TYPE. If it does not exist, return NULL_TREE. |
| If the member is ambiguously referenced, return `error_mark_node'. |
| Otherwise, return the FIELD_DECL. */ |
| |
| /* Do a 1-level search for NAME as a member of TYPE. The caller must |
| figure out whether it can access this field. (Since it is only one |
| level, this is reasonable.) */ |
| |
| static tree |
| lookup_field_1 (type, name) |
| tree type, name; |
| { |
| register tree field; |
| |
| if (TREE_CODE (type) == TEMPLATE_TYPE_PARM |
| || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM) |
| /* The TYPE_FIELDS of a TEMPLATE_TYPE_PARM are not fields at all; |
| instead TYPE_FIELDS is the TEMPLATE_PARM_INDEX. (Miraculously, |
| the code often worked even when we treated the index as a list |
| of fields!) */ |
| return NULL_TREE; |
| |
| if (TYPE_NAME (type) |
| && DECL_LANG_SPECIFIC (TYPE_NAME (type)) |
| && DECL_SORTED_FIELDS (TYPE_NAME (type))) |
| { |
| tree *fields = &TREE_VEC_ELT (DECL_SORTED_FIELDS (TYPE_NAME (type)), 0); |
| int lo = 0, hi = TREE_VEC_LENGTH (DECL_SORTED_FIELDS (TYPE_NAME (type))); |
| int i; |
| |
| while (lo < hi) |
| { |
| i = (lo + hi) / 2; |
| |
| #ifdef GATHER_STATISTICS |
| n_fields_searched++; |
| #endif /* GATHER_STATISTICS */ |
| |
| if (DECL_NAME (fields[i]) > name) |
| hi = i; |
| else if (DECL_NAME (fields[i]) < name) |
| lo = i + 1; |
| else |
| { |
| /* We might have a nested class and a field with the |
| same name; we sorted them appropriately via |
| field_decl_cmp, so just look for the last field with |
| this name. */ |
| while (i + 1 < hi |
| && DECL_NAME (fields[i+1]) == name) |
| ++i; |
| return fields[i]; |
| } |
| } |
| return NULL_TREE; |
| } |
| |
| field = TYPE_FIELDS (type); |
| |
| #ifdef GATHER_STATISTICS |
| n_calls_lookup_field_1++; |
| #endif /* GATHER_STATISTICS */ |
| while (field) |
| { |
| #ifdef GATHER_STATISTICS |
| n_fields_searched++; |
| #endif /* GATHER_STATISTICS */ |
| my_friendly_assert (DECL_P (field), 0); |
| if (DECL_NAME (field) == NULL_TREE |
| && ANON_AGGR_TYPE_P (TREE_TYPE (field))) |
| { |
| tree temp = lookup_field_1 (TREE_TYPE (field), name); |
| if (temp) |
| return temp; |
| } |
| if (TREE_CODE (field) == USING_DECL) |
| /* For now, we're just treating member using declarations as |
| old ARM-style access declarations. Thus, there's no reason |
| to return a USING_DECL, and the rest of the compiler can't |
| handle it. Once the class is defined, these are purged |
| from TYPE_FIELDS anyhow; see handle_using_decl. */ |
| ; |
| else if (DECL_NAME (field) == name) |
| { |
| if (TREE_CODE(field) == VAR_DECL |
| && (TREE_STATIC (field) || DECL_EXTERNAL (field))) |
| GNU_xref_ref(current_function_decl, |
| IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (field))); |
| return field; |
| } |
| field = TREE_CHAIN (field); |
| } |
| /* Not found. */ |
| if (name == vptr_identifier) |
| { |
| /* Give the user what s/he thinks s/he wants. */ |
| if (TYPE_POLYMORPHIC_P (type)) |
| return TYPE_VFIELD (type); |
| } |
| return NULL_TREE; |
| } |
| |
| /* There are a number of cases we need to be aware of here: |
| current_class_type current_function_decl |
| global NULL NULL |
| fn-local NULL SET |
| class-local SET NULL |
| class->fn SET SET |
| fn->class SET SET |
| |
| Those last two make life interesting. If we're in a function which is |
| itself inside a class, we need decls to go into the fn's decls (our |
| second case below). But if we're in a class and the class itself is |
| inside a function, we need decls to go into the decls for the class. To |
| achieve this last goal, we must see if, when both current_class_ptr and |
| current_function_decl are set, the class was declared inside that |
| function. If so, we know to put the decls into the class's scope. */ |
| |
| tree |
| current_scope () |
| { |
| if (current_function_decl == NULL_TREE) |
| return current_class_type; |
| if (current_class_type == NULL_TREE) |
| return current_function_decl; |
| if ((DECL_FUNCTION_MEMBER_P (current_function_decl) |
| && same_type_p (DECL_CONTEXT (current_function_decl), |
| current_class_type)) |
| || (DECL_FRIEND_CONTEXT (current_function_decl) |
| && same_type_p (DECL_FRIEND_CONTEXT (current_function_decl), |
| current_class_type))) |
| return current_function_decl; |
| |
| return current_class_type; |
| } |
| |
| /* Returns non-zero if we are currently in a function scope. Note |
| that this function returns zero if we are within a local class, but |
| not within a member function body of the local class. */ |
| |
| int |
| at_function_scope_p () |
| { |
| tree cs = current_scope (); |
| return cs && TREE_CODE (cs) == FUNCTION_DECL; |
| } |
| |
| /* Return the scope of DECL, as appropriate when doing name-lookup. */ |
| |
| tree |
| context_for_name_lookup (decl) |
| tree decl; |
| { |
| /* [class.union] |
| |
| For the purposes of name lookup, after the anonymous union |
| definition, the members of the anonymous union are considered to |
| have been defined in the scope in which the anonymous union is |
| declared. */ |
| tree context = DECL_CONTEXT (decl); |
| |
| while (context && TYPE_P (context) && ANON_AGGR_TYPE_P (context)) |
| context = TYPE_CONTEXT (context); |
| if (!context) |
| context = global_namespace; |
| |
| return context; |
| } |
| |
| /* Return a canonical BINFO if BINFO is a virtual base, or just BINFO |
| otherwise. */ |
| |
| static tree |
| canonical_binfo (binfo) |
| tree binfo; |
| { |
| return (TREE_VIA_VIRTUAL (binfo) |
| ? TYPE_BINFO (BINFO_TYPE (binfo)) : binfo); |
| } |
| |
| /* A queue function that simply ensures that we walk into the |
| canonical versions of virtual bases. */ |
| |
| static tree |
| dfs_canonical_queue (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| return canonical_binfo (binfo); |
| } |
| |
| /* Called via dfs_walk from assert_canonical_unmarked. */ |
| |
| static tree |
| dfs_assert_unmarked_p (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| my_friendly_assert (!BINFO_MARKED (binfo), 0); |
| return NULL_TREE; |
| } |
| |
| /* Asserts that all the nodes below BINFO (using the canonical |
| versions of virtual bases) are unmarked. */ |
| |
| static void |
| assert_canonical_unmarked (binfo) |
| tree binfo; |
| { |
| dfs_walk (binfo, dfs_assert_unmarked_p, dfs_canonical_queue, 0); |
| } |
| |
| /* If BINFO is marked, return a canonical version of BINFO. |
| Otherwise, return NULL_TREE. */ |
| |
| static tree |
| shared_marked_p (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| binfo = canonical_binfo (binfo); |
| return markedp (binfo, data); |
| } |
| |
| /* If BINFO is not marked, return a canonical version of BINFO. |
| Otherwise, return NULL_TREE. */ |
| |
| static tree |
| shared_unmarked_p (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| binfo = canonical_binfo (binfo); |
| return unmarkedp (binfo, data); |
| } |
| |
| /* The accessibility routines use BINFO_ACCESS for scratch space |
| during the computation of the accssibility of some declaration. */ |
| |
| #define BINFO_ACCESS(NODE) \ |
| ((access_kind) ((TREE_LANG_FLAG_1 (NODE) << 1) | TREE_LANG_FLAG_6 (NODE))) |
| |
| /* Set the access associated with NODE to ACCESS. */ |
| |
| #define SET_BINFO_ACCESS(NODE, ACCESS) \ |
| ((TREE_LANG_FLAG_1 (NODE) = (ACCESS & 2) != 0), \ |
| (TREE_LANG_FLAG_6 (NODE) = (ACCESS & 1) != 0)) |
| |
| /* Called from access_in_type via dfs_walk. Calculate the access to |
| DATA (which is really a DECL) in BINFO. */ |
| |
| static tree |
| dfs_access_in_type (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| tree decl = (tree) data; |
| tree type = BINFO_TYPE (binfo); |
| access_kind access = ak_none; |
| |
| if (context_for_name_lookup (decl) == type) |
| { |
| /* If we have desceneded to the scope of DECL, just note the |
| appropriate access. */ |
| if (TREE_PRIVATE (decl)) |
| access = ak_private; |
| else if (TREE_PROTECTED (decl)) |
| access = ak_protected; |
| else |
| access = ak_public; |
| } |
| else |
| { |
| /* First, check for an access-declaration that gives us more |
| access to the DECL. The CONST_DECL for an enumeration |
| constant will not have DECL_LANG_SPECIFIC, and thus no |
| DECL_ACCESS. */ |
| if (DECL_LANG_SPECIFIC (decl) && !DECL_DISCRIMINATOR_P (decl)) |
| { |
| tree decl_access = purpose_member (type, DECL_ACCESS (decl)); |
| if (decl_access) |
| access = ((access_kind) |
| TREE_INT_CST_LOW (TREE_VALUE (decl_access))); |
| } |
| |
| if (!access) |
| { |
| int i; |
| int n_baselinks; |
| tree binfos; |
| |
| /* Otherwise, scan our baseclasses, and pick the most favorable |
| access. */ |
| binfos = BINFO_BASETYPES (binfo); |
| n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0; |
| for (i = 0; i < n_baselinks; ++i) |
| { |
| tree base_binfo = TREE_VEC_ELT (binfos, i); |
| access_kind base_access |
| = BINFO_ACCESS (canonical_binfo (base_binfo)); |
| |
| if (base_access == ak_none || base_access == ak_private) |
| /* If it was not accessible in the base, or only |
| accessible as a private member, we can't access it |
| all. */ |
| base_access = ak_none; |
| else if (TREE_VIA_PROTECTED (base_binfo)) |
| /* Public and protected members in the base are |
| protected here. */ |
| base_access = ak_protected; |
| else if (!TREE_VIA_PUBLIC (base_binfo)) |
| /* Public and protected members in the base are |
| private here. */ |
| base_access = ak_private; |
| |
| /* See if the new access, via this base, gives more |
| access than our previous best access. */ |
| if (base_access != ak_none |
| && (base_access == ak_public |
| || (base_access == ak_protected |
| && access != ak_public) |
| || (base_access == ak_private |
| && access == ak_none))) |
| { |
| access = base_access; |
| |
| /* If the new access is public, we can't do better. */ |
| if (access == ak_public) |
| break; |
| } |
| } |
| } |
| } |
| |
| /* Note the access to DECL in TYPE. */ |
| SET_BINFO_ACCESS (binfo, access); |
| |
| /* Mark TYPE as visited so that if we reach it again we do not |
| duplicate our efforts here. */ |
| SET_BINFO_MARKED (binfo); |
| |
| return NULL_TREE; |
| } |
| |
| /* Return the access to DECL in TYPE. */ |
| |
| static access_kind |
| access_in_type (type, decl) |
| tree type; |
| tree decl; |
| { |
| tree binfo = TYPE_BINFO (type); |
| |
| /* We must take into account |
| |
| [class.paths] |
| |
| If a name can be reached by several paths through a multiple |
| inheritance graph, the access is that of the path that gives |
| most access. |
| |
| The algorithm we use is to make a post-order depth-first traversal |
| of the base-class hierarchy. As we come up the tree, we annotate |
| each node with the most lenient access. */ |
| dfs_walk_real (binfo, 0, dfs_access_in_type, shared_unmarked_p, decl); |
| dfs_walk (binfo, dfs_unmark, shared_marked_p, 0); |
| assert_canonical_unmarked (binfo); |
| |
| return BINFO_ACCESS (binfo); |
| } |
| |
| /* Called from dfs_accessible_p via dfs_walk. */ |
| |
| static tree |
| dfs_accessible_queue_p (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| if (BINFO_MARKED (binfo)) |
| return NULL_TREE; |
| |
| /* If this class is inherited via private or protected inheritance, |
| then we can't see it, unless we are a friend of the subclass. */ |
| if (!TREE_VIA_PUBLIC (binfo) |
| && !is_friend (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo)), |
| current_scope ())) |
| return NULL_TREE; |
| |
| return canonical_binfo (binfo); |
| } |
| |
| /* Called from dfs_accessible_p via dfs_walk. */ |
| |
| static tree |
| dfs_accessible_p (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| int protected_ok = data != 0; |
| access_kind access; |
| |
| SET_BINFO_MARKED (binfo); |
| access = BINFO_ACCESS (binfo); |
| if (access == ak_public || (access == ak_protected && protected_ok)) |
| return binfo; |
| else if (access != ak_none |
| && is_friend (BINFO_TYPE (binfo), current_scope ())) |
| return binfo; |
| |
| return NULL_TREE; |
| } |
| |
| /* Returns non-zero if it is OK to access DECL through an object |
| indiated by BINFO in the context of DERIVED. */ |
| |
| static int |
| protected_accessible_p (decl, derived, binfo) |
| tree decl; |
| tree derived; |
| tree binfo; |
| { |
| access_kind access; |
| |
| /* We're checking this clause from [class.access.base] |
| |
| m as a member of N is protected, and the reference occurs in a |
| member or friend of class N, or in a member or friend of a |
| class P derived from N, where m as a member of P is private or |
| protected. |
| |
| Here DERIVED is a possible P and DECL is m. accessible_p will |
| iterate over various values of N, but the access to m in DERIVED |
| does not change. |
| |
| Note that I believe that the passage above is wrong, and should read |
| "...is private or protected or public"; otherwise you get bizarre results |
| whereby a public using-decl can prevent you from accessing a protected |
| member of a base. (jason 2000/02/28) */ |
| |
| /* If DERIVED isn't derived from m's class, then it can't be a P. */ |
| if (!DERIVED_FROM_P (context_for_name_lookup (decl), derived)) |
| return 0; |
| |
| access = access_in_type (derived, decl); |
| |
| /* If m is inaccessible in DERIVED, then it's not a P. */ |
| if (access == ak_none) |
| return 0; |
| |
| /* [class.protected] |
| |
| When a friend or a member function of a derived class references |
| a protected nonstatic member of a base class, an access check |
| applies in addition to those described earlier in clause |
| _class.access_) Except when forming a pointer to member |
| (_expr.unary.op_), the access must be through a pointer to, |
| reference to, or object of the derived class itself (or any class |
| derived from that class) (_expr.ref_). If the access is to form |
| a pointer to member, the nested-name-specifier shall name the |
| derived class (or any class derived from that class). */ |
| if (DECL_NONSTATIC_MEMBER_P (decl)) |
| { |
| /* We can tell through what the reference is occurring by |
| chasing BINFO up to the root. */ |
| tree t = binfo; |
| while (BINFO_INHERITANCE_CHAIN (t)) |
| t = BINFO_INHERITANCE_CHAIN (t); |
| |
| if (!DERIVED_FROM_P (derived, BINFO_TYPE (t))) |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| /* Returns non-zero if SCOPE is a friend of a type which would be able |
| to access DECL through the object indicated by BINFO. */ |
| |
| static int |
| friend_accessible_p (scope, decl, binfo) |
| tree scope; |
| tree decl; |
| tree binfo; |
| { |
| tree befriending_classes; |
| tree t; |
| |
| if (!scope) |
| return 0; |
| |
| if (TREE_CODE (scope) == FUNCTION_DECL |
| || DECL_FUNCTION_TEMPLATE_P (scope)) |
| befriending_classes = DECL_BEFRIENDING_CLASSES (scope); |
| else if (TYPE_P (scope)) |
| befriending_classes = CLASSTYPE_BEFRIENDING_CLASSES (scope); |
| else |
| return 0; |
| |
| for (t = befriending_classes; t; t = TREE_CHAIN (t)) |
| if (protected_accessible_p (decl, TREE_VALUE (t), binfo)) |
| return 1; |
| |
| /* Nested classes are implicitly friends of their enclosing types, as |
| per core issue 45 (this is a change from the standard). */ |
| if (TYPE_P (scope)) |
| for (t = TYPE_CONTEXT (scope); t && TYPE_P (t); t = TYPE_CONTEXT (t)) |
| if (protected_accessible_p (decl, t, binfo)) |
| return 1; |
| |
| if (TREE_CODE (scope) == FUNCTION_DECL |
| || DECL_FUNCTION_TEMPLATE_P (scope)) |
| { |
| /* Perhaps this SCOPE is a member of a class which is a |
| friend. */ |
| if (DECL_CLASS_SCOPE_P (decl) |
| && friend_accessible_p (DECL_CONTEXT (scope), decl, binfo)) |
| return 1; |
| |
| /* Or an instantiation of something which is a friend. */ |
| if (DECL_TEMPLATE_INFO (scope)) |
| return friend_accessible_p (DECL_TI_TEMPLATE (scope), decl, binfo); |
| } |
| else if (CLASSTYPE_TEMPLATE_INFO (scope)) |
| return friend_accessible_p (CLASSTYPE_TI_TEMPLATE (scope), decl, binfo); |
| |
| return 0; |
| } |
| |
| /* Perform access control on TYPE_DECL VAL, which was looked up in TYPE. |
| This is fairly complex, so here's the design: |
| |
| The lang_extdef nonterminal sets type_lookups to NULL_TREE before we |
| start to process a top-level declaration. |
| As we process the decl-specifier-seq for the declaration, any types we |
| see that might need access control are passed to type_access_control, |
| which defers checking by adding them to type_lookups. |
| When we are done with the decl-specifier-seq, we record the lookups we've |
| seen in the lookups field of the typed_declspecs nonterminal. |
| When we process the first declarator, either in parse_decl or |
| begin_function_definition, we call save_type_access_control, |
| which stores the lookups from the decl-specifier-seq in |
| current_type_lookups. |
| As we finish with each declarator, we process everything in type_lookups |
| via decl_type_access_control, which resets type_lookups to the value of |
| current_type_lookups for subsequent declarators. |
| When we enter a function, we set type_lookups to error_mark_node, so all |
| lookups are processed immediately. */ |
| |
| void |
| type_access_control (type, val) |
| tree type, val; |
| { |
| if (val == NULL_TREE || TREE_CODE (val) != TYPE_DECL |
| || ! DECL_CLASS_SCOPE_P (val)) |
| return; |
| |
| if (type_lookups == error_mark_node) |
| enforce_access (type, val); |
| else if (! accessible_p (type, val)) |
| type_lookups = tree_cons (type, val, type_lookups); |
| } |
| |
| /* DECL is a declaration from a base class of TYPE, which was the |
| class used to name DECL. Return non-zero if, in the current |
| context, DECL is accessible. If TYPE is actually a BINFO node, |
| then we can tell in what context the access is occurring by looking |
| at the most derived class along the path indicated by BINFO. */ |
| |
| int |
| accessible_p (type, decl) |
| tree type; |
| tree decl; |
| |
| { |
| tree binfo; |
| tree t; |
| |
| /* Non-zero if it's OK to access DECL if it has protected |
| accessibility in TYPE. */ |
| int protected_ok = 0; |
| |
| /* If we're not checking access, everything is accessible. */ |
| if (!flag_access_control) |
| return 1; |
| |
| /* If this declaration is in a block or namespace scope, there's no |
| access control. */ |
| if (!TYPE_P (context_for_name_lookup (decl))) |
| return 1; |
| |
| if (!TYPE_P (type)) |
| { |
| binfo = type; |
| type = BINFO_TYPE (type); |
| } |
| else |
| binfo = TYPE_BINFO (type); |
| |
| /* [class.access.base] |
| |
| A member m is accessible when named in class N if |
| |
| --m as a member of N is public, or |
| |
| --m as a member of N is private, and the reference occurs in a |
| member or friend of class N, or |
| |
| --m as a member of N is protected, and the reference occurs in a |
| member or friend of class N, or in a member or friend of a |
| class P derived from N, where m as a member of P is private or |
| protected, or |
| |
| --there exists a base class B of N that is accessible at the point |
| of reference, and m is accessible when named in class B. |
| |
| We walk the base class hierarchy, checking these conditions. */ |
| |
| /* Figure out where the reference is occurring. Check to see if |
| DECL is private or protected in this scope, since that will |
| determine whether protected access is allowed. */ |
| if (current_class_type) |
| protected_ok = protected_accessible_p (decl, current_class_type, binfo); |
| |
| /* Now, loop through the classes of which we are a friend. */ |
| if (!protected_ok) |
| protected_ok = friend_accessible_p (current_scope (), decl, binfo); |
| |
| /* Standardize the binfo that access_in_type will use. We don't |
| need to know what path was chosen from this point onwards. */ |
| binfo = TYPE_BINFO (type); |
| |
| /* Compute the accessibility of DECL in the class hierarchy |
| dominated by type. */ |
| access_in_type (type, decl); |
| /* Walk the hierarchy again, looking for a base class that allows |
| access. */ |
| t = dfs_walk (binfo, dfs_accessible_p, |
| dfs_accessible_queue_p, |
| protected_ok ? &protected_ok : 0); |
| /* Clear any mark bits. Note that we have to walk the whole tree |
| here, since we have aborted the previous walk from some point |
| deep in the tree. */ |
| dfs_walk (binfo, dfs_unmark, dfs_canonical_queue, 0); |
| assert_canonical_unmarked (binfo); |
| |
| return t != NULL_TREE; |
| } |
| |
| /* Routine to see if the sub-object denoted by the binfo PARENT can be |
| found as a base class and sub-object of the object denoted by |
| BINFO. MOST_DERIVED is the most derived type of the hierarchy being |
| searched. */ |
| |
| static int |
| is_subobject_of_p (parent, binfo, most_derived) |
| tree parent, binfo, most_derived; |
| { |
| tree binfos; |
| int i, n_baselinks; |
| |
| if (parent == binfo) |
| return 1; |
| |
| binfos = BINFO_BASETYPES (binfo); |
| n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0; |
| |
| /* Iterate the base types. */ |
| for (i = 0; i < n_baselinks; i++) |
| { |
| tree base_binfo = TREE_VEC_ELT (binfos, i); |
| if (!CLASS_TYPE_P (TREE_TYPE (base_binfo))) |
| /* If we see a TEMPLATE_TYPE_PARM, or some such, as a base |
| class there's no way to descend into it. */ |
| continue; |
| |
| if (is_subobject_of_p (parent, |
| CANONICAL_BINFO (base_binfo, most_derived), |
| most_derived)) |
| return 1; |
| } |
| return 0; |
| } |
| |
| struct lookup_field_info { |
| /* The type in which we're looking. */ |
| tree type; |
| /* The name of the field for which we're looking. */ |
| tree name; |
| /* If non-NULL, the current result of the lookup. */ |
| tree rval; |
| /* The path to RVAL. */ |
| tree rval_binfo; |
| /* If non-NULL, the lookup was ambiguous, and this is a list of the |
| candidates. */ |
| tree ambiguous; |
| /* If non-zero, we are looking for types, not data members. */ |
| int want_type; |
| /* If non-zero, RVAL was found by looking through a dependent base. */ |
| int from_dep_base_p; |
| /* If something went wrong, a message indicating what. */ |
| const char *errstr; |
| }; |
| |
| /* Returns non-zero if BINFO is not hidden by the value found by the |
| lookup so far. If BINFO is hidden, then there's no need to look in |
| it. DATA is really a struct lookup_field_info. Called from |
| lookup_field via breadth_first_search. */ |
| |
| static tree |
| lookup_field_queue_p (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| struct lookup_field_info *lfi = (struct lookup_field_info *) data; |
| |
| /* Don't look for constructors or destructors in base classes. */ |
| if (IDENTIFIER_CTOR_OR_DTOR_P (lfi->name)) |
| return NULL_TREE; |
| |
| /* If this base class is hidden by the best-known value so far, we |
| don't need to look. */ |
| if (!lfi->from_dep_base_p && lfi->rval_binfo |
| && is_subobject_of_p (binfo, lfi->rval_binfo, lfi->type)) |
| return NULL_TREE; |
| |
| return CANONICAL_BINFO (binfo, lfi->type); |
| } |
| |
| /* Within the scope of a template class, you can refer to the to the |
| current specialization with the name of the template itself. For |
| example: |
| |
| template <typename T> struct S { S* sp; } |
| |
| Returns non-zero if DECL is such a declaration in a class TYPE. */ |
| |
| static int |
| template_self_reference_p (type, decl) |
| tree type; |
| tree decl; |
| { |
| return (CLASSTYPE_USE_TEMPLATE (type) |
| && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type)) |
| && TREE_CODE (decl) == TYPE_DECL |
| && DECL_ARTIFICIAL (decl) |
| && DECL_NAME (decl) == constructor_name (type)); |
| } |
| |
| |
| /* Nonzero for a class member means that it is shared between all objects |
| of that class. |
| |
| [class.member.lookup]:If the resulting set of declarations are not all |
| from sub-objects of the same type, or the set has a nonstatic member |
| and includes members from distinct sub-objects, there is an ambiguity |
| and the program is ill-formed. |
| |
| This function checks that T contains no nonstatic members. */ |
| |
| static int |
| shared_member_p (t) |
| tree t; |
| { |
| if (TREE_CODE (t) == VAR_DECL || TREE_CODE (t) == TYPE_DECL \ |
| || TREE_CODE (t) == CONST_DECL) |
| return 1; |
| if (is_overloaded_fn (t)) |
| { |
| for (; t; t = OVL_NEXT (t)) |
| { |
| tree fn = OVL_CURRENT (t); |
| if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)) |
| return 0; |
| } |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* DATA is really a struct lookup_field_info. Look for a field with |
| the name indicated there in BINFO. If this function returns a |
| non-NULL value it is the result of the lookup. Called from |
| lookup_field via breadth_first_search. */ |
| |
| static tree |
| lookup_field_r (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| struct lookup_field_info *lfi = (struct lookup_field_info *) data; |
| tree type = BINFO_TYPE (binfo); |
| tree nval = NULL_TREE; |
| int from_dep_base_p; |
| |
| /* First, look for a function. There can't be a function and a data |
| member with the same name, and if there's a function and a type |
| with the same name, the type is hidden by the function. */ |
| if (!lfi->want_type) |
| { |
| int idx = lookup_fnfields_1 (type, lfi->name); |
| if (idx >= 0) |
| nval = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (type), idx); |
| } |
| |
| if (!nval) |
| /* Look for a data member or type. */ |
| nval = lookup_field_1 (type, lfi->name); |
| |
| /* If there is no declaration with the indicated name in this type, |
| then there's nothing to do. */ |
| if (!nval) |
| return NULL_TREE; |
| |
| /* If we're looking up a type (as with an elaborated type specifier) |
| we ignore all non-types we find. */ |
| if (lfi->want_type && TREE_CODE (nval) != TYPE_DECL) |
| { |
| nval = purpose_member (lfi->name, CLASSTYPE_TAGS (type)); |
| if (nval) |
| nval = TYPE_MAIN_DECL (TREE_VALUE (nval)); |
| else |
| return NULL_TREE; |
| } |
| |
| /* You must name a template base class with a template-id. */ |
| if (!same_type_p (type, lfi->type) |
| && template_self_reference_p (type, nval)) |
| return NULL_TREE; |
| |
| from_dep_base_p = dependent_base_p (binfo); |
| if (lfi->from_dep_base_p && !from_dep_base_p) |
| { |
| /* If the new declaration is not found via a dependent base, and |
| the old one was, then we must prefer the new one. We weren't |
| really supposed to be able to find the old one, so we don't |
| want to be affected by a specialization. Consider: |
| |
| struct B { typedef int I; }; |
| template <typename T> struct D1 : virtual public B {}; |
| template <typename T> struct D : |
| public D1, virtual pubic B { I i; }; |
| |
| The `I' in `D<T>' is unambigousuly `B::I', regardless of how |
| D1 is specialized. */ |
| lfi->from_dep_base_p = 0; |
| lfi->rval = NULL_TREE; |
| lfi->rval_binfo = NULL_TREE; |
| lfi->ambiguous = NULL_TREE; |
| lfi->errstr = 0; |
| } |
| else if (lfi->rval_binfo && !lfi->from_dep_base_p && from_dep_base_p) |
| /* Similarly, if the old declaration was not found via a dependent |
| base, and the new one is, ignore the new one. */ |
| return NULL_TREE; |
| |
| /* If the lookup already found a match, and the new value doesn't |
| hide the old one, we might have an ambiguity. */ |
| if (lfi->rval_binfo && !is_subobject_of_p (lfi->rval_binfo, binfo, lfi->type)) |
| { |
| if (nval == lfi->rval && shared_member_p (nval)) |
| /* The two things are really the same. */ |
| ; |
| else if (is_subobject_of_p (binfo, lfi->rval_binfo, lfi->type)) |
| /* The previous value hides the new one. */ |
| ; |
| else |
| { |
| /* We have a real ambiguity. We keep a chain of all the |
| candidates. */ |
| if (!lfi->ambiguous && lfi->rval) |
| { |
| /* This is the first time we noticed an ambiguity. Add |
| what we previously thought was a reasonable candidate |
| to the list. */ |
| lfi->ambiguous = tree_cons (NULL_TREE, lfi->rval, NULL_TREE); |
| TREE_TYPE (lfi->ambiguous) = error_mark_node; |
| } |
| |
| /* Add the new value. */ |
| lfi->ambiguous = tree_cons (NULL_TREE, nval, lfi->ambiguous); |
| TREE_TYPE (lfi->ambiguous) = error_mark_node; |
| lfi->errstr = "request for member `%D' is ambiguous"; |
| } |
| } |
| else |
| { |
| /* If the thing we're looking for is a virtual base class, then |
| we know we've got what we want at this point; there's no way |
| to get an ambiguity. */ |
| if (VBASE_NAME_P (lfi->name)) |
| { |
| lfi->rval = nval; |
| return nval; |
| } |
| |
| if (from_dep_base_p && TREE_CODE (nval) != TYPE_DECL |
| /* We need to return a member template class so we can |
| define partial specializations. Is there a better |
| way? */ |
| && !DECL_CLASS_TEMPLATE_P (nval)) |
| /* The thing we're looking for isn't a type, so the implicit |
| typename extension doesn't apply, so we just pretend we |
| didn't find anything. */ |
| return NULL_TREE; |
| |
| lfi->rval = nval; |
| lfi->from_dep_base_p = from_dep_base_p; |
| lfi->rval_binfo = binfo; |
| } |
| |
| return NULL_TREE; |
| } |
| |
| /* Look for a member named NAME in an inheritance lattice dominated by |
| XBASETYPE. If PROTECT is 0 or two, we do not check access. If it is |
| 1, we enforce accessibility. If PROTECT is zero, then, for an |
| ambiguous lookup, we return NULL. If PROTECT is 1, we issue an |
| error message. If PROTECT is 2, we return a TREE_LIST whose |
| TREE_TYPE is error_mark_node and whose TREE_VALUEs are the list of |
| ambiguous candidates. |
| |
| WANT_TYPE is 1 when we should only return TYPE_DECLs, if no |
| TYPE_DECL can be found return NULL_TREE. */ |
| |
| tree |
| lookup_member (xbasetype, name, protect, want_type) |
| register tree xbasetype, name; |
| int protect, want_type; |
| { |
| tree rval, rval_binfo = NULL_TREE; |
| tree type = NULL_TREE, basetype_path = NULL_TREE; |
| struct lookup_field_info lfi; |
| |
| /* rval_binfo is the binfo associated with the found member, note, |
| this can be set with useful information, even when rval is not |
| set, because it must deal with ALL members, not just non-function |
| members. It is used for ambiguity checking and the hidden |
| checks. Whereas rval is only set if a proper (not hidden) |
| non-function member is found. */ |
| |
| const char *errstr = 0; |
| |
| if (xbasetype == current_class_type && TYPE_BEING_DEFINED (xbasetype) |
| && IDENTIFIER_CLASS_VALUE (name)) |
| { |
| tree field = IDENTIFIER_CLASS_VALUE (name); |
| if (TREE_CODE (field) != FUNCTION_DECL |
| && ! (want_type && TREE_CODE (field) != TYPE_DECL)) |
| /* We're in the scope of this class, and the value has already |
| been looked up. Just return the cached value. */ |
| return field; |
| } |
| |
| if (TREE_CODE (xbasetype) == TREE_VEC) |
| { |
| type = BINFO_TYPE (xbasetype); |
| basetype_path = xbasetype; |
| } |
| else if (IS_AGGR_TYPE_CODE (TREE_CODE (xbasetype))) |
| { |
| type = xbasetype; |
| basetype_path = TYPE_BINFO (type); |
| my_friendly_assert (BINFO_INHERITANCE_CHAIN (basetype_path) == NULL_TREE, |
| 980827); |
| } |
| else |
| my_friendly_abort (97); |
| |
| complete_type (type); |
| |
| #ifdef GATHER_STATISTICS |
| n_calls_lookup_field++; |
| #endif /* GATHER_STATISTICS */ |
| |
| memset ((PTR) &lfi, 0, sizeof (lfi)); |
| lfi.type = type; |
| lfi.name = name; |
| lfi.want_type = want_type; |
| bfs_walk (basetype_path, &lookup_field_r, &lookup_field_queue_p, &lfi); |
| rval = lfi.rval; |
| rval_binfo = lfi.rval_binfo; |
| if (rval_binfo) |
| type = BINFO_TYPE (rval_binfo); |
| errstr = lfi.errstr; |
| |
| /* If we are not interested in ambiguities, don't report them; |
| just return NULL_TREE. */ |
| if (!protect && lfi.ambiguous) |
| return NULL_TREE; |
| |
| if (protect == 2) |
| { |
| if (lfi.ambiguous) |
| return lfi.ambiguous; |
| else |
| protect = 0; |
| } |
| |
| /* [class.access] |
| |
| In the case of overloaded function names, access control is |
| applied to the function selected by overloaded resolution. */ |
| if (rval && protect && !is_overloaded_fn (rval) |
| && !enforce_access (xbasetype, rval)) |
| return error_mark_node; |
| |
| if (errstr && protect) |
| { |
| cp_error (errstr, name, type); |
| if (lfi.ambiguous) |
| print_candidates (lfi.ambiguous); |
| rval = error_mark_node; |
| } |
| |
| /* If the thing we found was found via the implicit typename |
| extension, build the typename type. */ |
| if (rval && lfi.from_dep_base_p && !DECL_CLASS_TEMPLATE_P (rval)) |
| rval = TYPE_STUB_DECL (build_typename_type (BINFO_TYPE (basetype_path), |
| name, name, |
| TREE_TYPE (rval))); |
| |
| if (rval && is_overloaded_fn (rval)) |
| { |
| /* Note that the binfo we put in the baselink is the binfo where |
| we found the functions, which we need for overload |
| resolution, but which should not be passed to enforce_access; |
| rather, enforce_access wants a binfo which refers to the |
| scope in which we started looking for the function. This |
| will generally be the binfo passed into this function as |
| xbasetype. */ |
| |
| rval = tree_cons (rval_binfo, rval, NULL_TREE); |
| SET_BASELINK_P (rval); |
| } |
| |
| return rval; |
| } |
| |
| /* Like lookup_member, except that if we find a function member we |
| return NULL_TREE. */ |
| |
| tree |
| lookup_field (xbasetype, name, protect, want_type) |
| register tree xbasetype, name; |
| int protect, want_type; |
| { |
| tree rval = lookup_member (xbasetype, name, protect, want_type); |
| |
| /* Ignore functions. */ |
| if (rval && TREE_CODE (rval) == TREE_LIST) |
| return NULL_TREE; |
| |
| return rval; |
| } |
| |
| /* Like lookup_member, except that if we find a non-function member we |
| return NULL_TREE. */ |
| |
| tree |
| lookup_fnfields (xbasetype, name, protect) |
| register tree xbasetype, name; |
| int protect; |
| { |
| tree rval = lookup_member (xbasetype, name, protect, /*want_type=*/0); |
| |
| /* Ignore non-functions. */ |
| if (rval && TREE_CODE (rval) != TREE_LIST) |
| return NULL_TREE; |
| |
| return rval; |
| } |
| |
| /* TYPE is a class type. Return the index of the fields within |
| the method vector with name NAME, or -1 is no such field exists. */ |
| |
| int |
| lookup_fnfields_1 (type, name) |
| tree type, name; |
| { |
| tree method_vec |
| = CLASS_TYPE_P (type) ? CLASSTYPE_METHOD_VEC (type) : NULL_TREE; |
| |
| if (method_vec != 0) |
| { |
| register int i; |
| register tree *methods = &TREE_VEC_ELT (method_vec, 0); |
| int len = TREE_VEC_LENGTH (method_vec); |
| tree tmp; |
| |
| #ifdef GATHER_STATISTICS |
| n_calls_lookup_fnfields_1++; |
| #endif /* GATHER_STATISTICS */ |
| |
| /* Constructors are first... */ |
| if (name == ctor_identifier) |
| return (methods[CLASSTYPE_CONSTRUCTOR_SLOT] |
| ? CLASSTYPE_CONSTRUCTOR_SLOT : -1); |
| /* and destructors are second. */ |
| if (name == dtor_identifier) |
| return (methods[CLASSTYPE_DESTRUCTOR_SLOT] |
| ? CLASSTYPE_DESTRUCTOR_SLOT : -1); |
| |
| for (i = CLASSTYPE_FIRST_CONVERSION_SLOT; |
| i < len && methods[i]; |
| ++i) |
| { |
| #ifdef GATHER_STATISTICS |
| n_outer_fields_searched++; |
| #endif /* GATHER_STATISTICS */ |
| |
| tmp = OVL_CURRENT (methods[i]); |
| if (DECL_NAME (tmp) == name) |
| return i; |
| |
| /* If the type is complete and we're past the conversion ops, |
| switch to binary search. */ |
| if (! DECL_CONV_FN_P (tmp) |
| && COMPLETE_TYPE_P (type)) |
| { |
| int lo = i + 1, hi = len; |
| |
| while (lo < hi) |
| { |
| i = (lo + hi) / 2; |
| |
| #ifdef GATHER_STATISTICS |
| n_outer_fields_searched++; |
| #endif /* GATHER_STATISTICS */ |
| |
| tmp = DECL_NAME (OVL_CURRENT (methods[i])); |
| |
| if (tmp > name) |
| hi = i; |
| else if (tmp < name) |
| lo = i + 1; |
| else |
| return i; |
| } |
| break; |
| } |
| } |
| |
| /* If we didn't find it, it might have been a template |
| conversion operator. (Note that we don't look for this case |
| above so that we will always find specializations first.) */ |
| if (IDENTIFIER_TYPENAME_P (name)) |
| { |
| for (i = CLASSTYPE_FIRST_CONVERSION_SLOT; |
| i < len && methods[i]; |
| ++i) |
| { |
| tmp = OVL_CURRENT (methods[i]); |
| if (! DECL_CONV_FN_P (tmp)) |
| { |
| /* Since all conversion operators come first, we know |
| there is no such operator. */ |
| break; |
| } |
| else if (TREE_CODE (tmp) == TEMPLATE_DECL) |
| return i; |
| } |
| } |
| } |
| |
| return -1; |
| } |
| |
| /* Walk the class hierarchy dominated by TYPE. FN is called for each |
| type in the hierarchy, in a breadth-first preorder traversal. . |
| If it ever returns a non-NULL value, that value is immediately |
| returned and the walk is terminated. At each node FN, is passed a |
| BINFO indicating the path from the curently visited base-class to |
| TYPE. Before each base-class is walked QFN is called. If the |
| value returned is non-zero, the base-class is walked; otherwise it |
| is not. If QFN is NULL, it is treated as a function which always |
| returns 1. Both FN and QFN are passed the DATA whenever they are |
| called. */ |
| |
| static tree |
| bfs_walk (binfo, fn, qfn, data) |
| tree binfo; |
| tree (*fn) PARAMS ((tree, void *)); |
| tree (*qfn) PARAMS ((tree, void *)); |
| void *data; |
| { |
| size_t head; |
| size_t tail; |
| tree rval = NULL_TREE; |
| /* An array of the base classes of BINFO. These will be built up in |
| breadth-first order, except where QFN prunes the search. */ |
| varray_type bfs_bases; |
| |
| /* Start with enough room for ten base classes. That will be enough |
| for most hierarchies. */ |
| VARRAY_TREE_INIT (bfs_bases, 10, "search_stack"); |
| |
| /* Put the first type into the stack. */ |
| VARRAY_TREE (bfs_bases, 0) = binfo; |
| tail = 1; |
| |
| for (head = 0; head < tail; ++head) |
| { |
| int i; |
| int n_baselinks; |
| tree binfos; |
| |
| /* Pull the next type out of the queue. */ |
| binfo = VARRAY_TREE (bfs_bases, head); |
| |
| /* If this is the one we're looking for, we're done. */ |
| rval = (*fn) (binfo, data); |
| if (rval) |
| break; |
| |
| /* Queue up the base types. */ |
| binfos = BINFO_BASETYPES (binfo); |
| n_baselinks = binfos ? TREE_VEC_LENGTH (binfos): 0; |
| for (i = 0; i < n_baselinks; i++) |
| { |
| tree base_binfo = TREE_VEC_ELT (binfos, i); |
| |
| if (qfn) |
| base_binfo = (*qfn) (base_binfo, data); |
| |
| if (base_binfo) |
| { |
| if (tail == VARRAY_SIZE (bfs_bases)) |
| VARRAY_GROW (bfs_bases, 2 * VARRAY_SIZE (bfs_bases)); |
| VARRAY_TREE (bfs_bases, tail) = base_binfo; |
| ++tail; |
| } |
| } |
| } |
| |
| /* Clean up. */ |
| VARRAY_FREE (bfs_bases); |
| |
| return rval; |
| } |
| |
| /* Exactly like bfs_walk, except that a depth-first traversal is |
| performed, and PREFN is called in preorder, while POSTFN is called |
| in postorder. */ |
| |
| tree |
| dfs_walk_real (binfo, prefn, postfn, qfn, data) |
| tree binfo; |
| tree (*prefn) PARAMS ((tree, void *)); |
| tree (*postfn) PARAMS ((tree, void *)); |
| tree (*qfn) PARAMS ((tree, void *)); |
| void *data; |
| { |
| int i; |
| int n_baselinks; |
| tree binfos; |
| tree rval = NULL_TREE; |
| |
| /* Call the pre-order walking function. */ |
| if (prefn) |
| { |
| rval = (*prefn) (binfo, data); |
| if (rval) |
| return rval; |
| } |
| |
| /* Process the basetypes. */ |
| binfos = BINFO_BASETYPES (binfo); |
| n_baselinks = BINFO_N_BASETYPES (binfo); |
| for (i = 0; i < n_baselinks; i++) |
| { |
| tree base_binfo = TREE_VEC_ELT (binfos, i); |
| |
| if (qfn) |
| base_binfo = (*qfn) (base_binfo, data); |
| |
| if (base_binfo) |
| { |
| rval = dfs_walk_real (base_binfo, prefn, postfn, qfn, data); |
| if (rval) |
| return rval; |
| } |
| } |
| |
| /* Call the post-order walking function. */ |
| if (postfn) |
| rval = (*postfn) (binfo, data); |
| |
| return rval; |
| } |
| |
| /* Exactly like bfs_walk, except that a depth-first post-order traversal is |
| performed. */ |
| |
| tree |
| dfs_walk (binfo, fn, qfn, data) |
| tree binfo; |
| tree (*fn) PARAMS ((tree, void *)); |
| tree (*qfn) PARAMS ((tree, void *)); |
| void *data; |
| { |
| return dfs_walk_real (binfo, 0, fn, qfn, data); |
| } |
| |
| /* Returns > 0 if a function with type DRETTYPE overriding a function |
| with type BRETTYPE is covariant, as defined in [class.virtual]. |
| |
| Returns 1 if trivial covariance, 2 if non-trivial (requiring runtime |
| adjustment), or -1 if pedantically invalid covariance. */ |
| |
| static int |
| covariant_return_p (brettype, drettype) |
| tree brettype, drettype; |
| { |
| tree binfo; |
| |
| if (TREE_CODE (brettype) == FUNCTION_DECL) |
| { |
| brettype = TREE_TYPE (TREE_TYPE (brettype)); |
| drettype = TREE_TYPE (TREE_TYPE (drettype)); |
| } |
| else if (TREE_CODE (brettype) == METHOD_TYPE) |
| { |
| brettype = TREE_TYPE (brettype); |
| drettype = TREE_TYPE (drettype); |
| } |
| |
| if (same_type_p (brettype, drettype)) |
| return 0; |
| |
| if (! (TREE_CODE (brettype) == TREE_CODE (drettype) |
| && (TREE_CODE (brettype) == POINTER_TYPE |
| || TREE_CODE (brettype) == REFERENCE_TYPE) |
| && TYPE_QUALS (brettype) == TYPE_QUALS (drettype))) |
| return 0; |
| |
| if (! can_convert (brettype, drettype)) |
| return 0; |
| |
| brettype = TREE_TYPE (brettype); |
| drettype = TREE_TYPE (drettype); |
| |
| /* If not pedantic, allow any standard pointer conversion. */ |
| if (! IS_AGGR_TYPE (drettype) || ! IS_AGGR_TYPE (brettype)) |
| return -1; |
| |
| binfo = get_binfo (brettype, drettype, 1); |
| |
| /* If we get an error_mark_node from get_binfo, it already complained, |
| so let's just succeed. */ |
| if (binfo == error_mark_node) |
| return 1; |
| |
| if (! BINFO_OFFSET_ZEROP (binfo) || TREE_VIA_VIRTUAL (binfo)) |
| return 2; |
| return 1; |
| } |
| |
| /* Check that virtual overrider OVERRIDER is acceptable for base function |
| BASEFN. Issue diagnostic, and return zero, if unacceptable. */ |
| |
| static int |
| check_final_overrider (overrider, basefn) |
| tree overrider, basefn; |
| { |
| tree over_type = TREE_TYPE (overrider); |
| tree base_type = TREE_TYPE (basefn); |
| tree over_return = TREE_TYPE (over_type); |
| tree base_return = TREE_TYPE (base_type); |
| tree over_throw = TYPE_RAISES_EXCEPTIONS (over_type); |
| tree base_throw = TYPE_RAISES_EXCEPTIONS (base_type); |
| int i; |
| |
| if (same_type_p (base_return, over_return)) |
| /* OK */; |
| else if ((i = covariant_return_p (base_return, over_return))) |
| { |
| if (i == 2) |
| sorry ("adjusting pointers for covariant returns"); |
| |
| if (pedantic && i == -1) |
| { |
| cp_pedwarn_at ("invalid covariant return type for `%#D'", overrider); |
| cp_pedwarn_at (" overriding `%#D' (must be pointer or reference to class)", basefn); |
| } |
| } |
| else if (IS_AGGR_TYPE_2 (base_return, over_return) |
| && same_or_base_type_p (base_return, over_return)) |
| { |
| cp_error_at ("invalid covariant return type for `%#D'", overrider); |
| cp_error_at (" overriding `%#D' (must use pointer or reference)", basefn); |
| return 0; |
| } |
| else if (IDENTIFIER_ERROR_LOCUS (DECL_ASSEMBLER_NAME (overrider)) == NULL_TREE) |
| { |
| cp_error_at ("conflicting return type specified for `%#D'", overrider); |
| cp_error_at (" overriding `%#D'", basefn); |
| SET_IDENTIFIER_ERROR_LOCUS (DECL_ASSEMBLER_NAME (overrider), |
| DECL_CONTEXT (overrider)); |
| return 0; |
| } |
| |
| /* Check throw specifier is subset. */ |
| if (!comp_except_specs (base_throw, over_throw, 0)) |
| { |
| cp_error_at ("looser throw specifier for `%#F'", overrider); |
| cp_error_at (" overriding `%#F'", basefn); |
| return 0; |
| } |
| return 1; |
| } |
| |
| /* Given a class TYPE, and a function decl FNDECL, look for |
| virtual functions in TYPE's hierarchy which FNDECL overrides. |
| We do not look in TYPE itself, only its bases. |
| |
| Returns non-zero, if we find any. Set FNDECL's DECL_VIRTUAL_P, if we |
| find that it overrides anything. |
| |
| We check that every function which is overridden, is correctly |
| overridden. */ |
| |
| int |
| look_for_overrides (type, fndecl) |
| tree type, fndecl; |
| { |
| tree binfo = TYPE_BINFO (type); |
| tree basebinfos = BINFO_BASETYPES (binfo); |
| int nbasebinfos = basebinfos ? TREE_VEC_LENGTH (basebinfos) : 0; |
| int ix; |
| int found = 0; |
| |
| for (ix = 0; ix != nbasebinfos; ix++) |
| { |
| tree basetype = BINFO_TYPE (TREE_VEC_ELT (basebinfos, ix)); |
| |
| if (TYPE_POLYMORPHIC_P (basetype)) |
| found += look_for_overrides_r (basetype, fndecl); |
| } |
| return found; |
| } |
| |
| /* Look in TYPE for virtual functions overridden by FNDECL. Check both |
| TYPE itself and its bases. */ |
| |
| static int |
| look_for_overrides_r (type, fndecl) |
| tree type, fndecl; |
| { |
| int ix; |
| |
| if (DECL_DESTRUCTOR_P (fndecl)) |
| ix = CLASSTYPE_DESTRUCTOR_SLOT; |
| else |
| ix = lookup_fnfields_1 (type, DECL_NAME (fndecl)); |
| if (ix >= 0) |
| { |
| tree fns = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (type), ix); |
| tree dtypes = TYPE_ARG_TYPES (TREE_TYPE (fndecl)); |
| tree thistype = DECL_STATIC_FUNCTION_P (fndecl) |
| ? NULL_TREE : TREE_TYPE (TREE_VALUE (dtypes)); |
| |
| for (; fns; fns = OVL_NEXT (fns)) |
| { |
| tree fn = OVL_CURRENT (fns); |
| tree btypes = TYPE_ARG_TYPES (TREE_TYPE (fn)); |
| |
| if (!DECL_VIRTUAL_P (fn)) |
| /* Not a virtual */; |
| else if (DECL_CONTEXT (fn) != type) |
| /* Introduced with a using declaration */; |
| else if (thistype == NULL_TREE) |
| { |
| if (compparms (TREE_CHAIN (btypes), dtypes)) |
| { |
| /* A static member function cannot match an inherited |
| virtual member function. */ |
| cp_error_at ("`%#D' cannot be declared", fndecl); |
| cp_error_at (" since `%#D' declared in base class", fn); |
| return 1; |
| } |
| } |
| else if (same_signature_p (fndecl, fn)) |
| { |
| /* It's definitely virtual, even if not explicitly set. */ |
| DECL_VIRTUAL_P (fndecl) = 1; |
| check_final_overrider (fndecl, fn); |
| |
| return 1; |
| } |
| } |
| } |
| /* We failed to find one declared in this class. Look in its bases. */ |
| return look_for_overrides (type, fndecl); |
| } |
| |
| /* A queue function for dfs_walk that skips any nonprimary virtual |
| bases and any already marked bases. */ |
| |
| tree |
| dfs_skip_nonprimary_vbases_unmarkedp (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| if (TREE_VIA_VIRTUAL (binfo) && !BINFO_PRIMARY_P (binfo)) |
| /* This is a non-primary virtual base. Skip it. */ |
| return NULL_TREE; |
| |
| return unmarkedp (binfo, NULL); |
| } |
| |
| /* A queue function for dfs_walk that skips any nonprimary virtual |
| bases and any unmarked bases. */ |
| |
| tree |
| dfs_skip_nonprimary_vbases_markedp (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| if (TREE_VIA_VIRTUAL (binfo) && !BINFO_PRIMARY_P (binfo)) |
| /* This is a non-primary virtual base. Skip it. */ |
| return NULL_TREE; |
| |
| return markedp (binfo, NULL); |
| } |
| |
| /* If BINFO is a non-primary virtual baseclass (in the hierarchy |
| dominated by TYPE), and no primary copy appears anywhere in the |
| hierarchy, return the shared copy. If a primary copy appears |
| elsewhere, return NULL_TREE. Otherwise, return BINFO itself; it is |
| either a non-virtual base or a primary virtual base. */ |
| |
| static tree |
| get_shared_vbase_if_not_primary (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| if (TREE_VIA_VIRTUAL (binfo) && !BINFO_PRIMARY_P (binfo)) |
| { |
| tree type = (tree) data; |
| |
| if (TREE_CODE (type) == TREE_LIST) |
| type = TREE_PURPOSE (type); |
| |
| /* This is a non-primary virtual base. If there is no primary |
| version, get the shared version. */ |
| binfo = binfo_for_vbase (BINFO_TYPE (binfo), type); |
| if (BINFO_PRIMARY_P (binfo)) |
| return NULL_TREE; |
| } |
| |
| return binfo; |
| } |
| |
| /* A queue function to use with dfs_walk that prevents travel into any |
| nonprimary virtual base, or its baseclasses. DATA should be the |
| type of the complete object, or a TREE_LIST whose TREE_PURPOSE is |
| the type of the complete object. By using this function as a queue |
| function, you will walk over exactly those BINFOs that actually |
| exist in the complete object, including those for virtual base |
| classes. If you SET_BINFO_MARKED for each binfo you process, you |
| are further guaranteed that you will walk into each virtual base |
| class exactly once. */ |
| |
| tree |
| dfs_unmarked_real_bases_queue_p (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| binfo = get_shared_vbase_if_not_primary (binfo, data); |
| return binfo ? unmarkedp (binfo, NULL) : NULL_TREE; |
| } |
| |
| /* Like dfs_unmarked_real_bases_queue_p but walks only into things |
| that are marked, rather than unmarked. */ |
| |
| tree |
| dfs_marked_real_bases_queue_p (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| binfo = get_shared_vbase_if_not_primary (binfo, data); |
| return binfo ? markedp (binfo, NULL) : NULL_TREE; |
| } |
| |
| /* A queue function that skips all virtual bases (and their |
| bases). */ |
| |
| tree |
| dfs_skip_vbases (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| if (TREE_VIA_VIRTUAL (binfo)) |
| return NULL_TREE; |
| |
| return binfo; |
| } |
| |
| /* Called via dfs_walk from dfs_get_pure_virtuals. */ |
| |
| static tree |
| dfs_get_pure_virtuals (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| tree type = (tree) data; |
| |
| /* We're not interested in primary base classes; the derived class |
| of which they are a primary base will contain the information we |
| need. */ |
| if (!BINFO_PRIMARY_P (binfo)) |
| { |
| tree virtuals; |
| |
| for (virtuals = BINFO_VIRTUALS (binfo); |
| virtuals; |
| virtuals = TREE_CHAIN (virtuals)) |
| if (DECL_PURE_VIRTUAL_P (BV_FN (virtuals))) |
| CLASSTYPE_PURE_VIRTUALS (type) |
| = tree_cons (NULL_TREE, BV_FN (virtuals), |
| CLASSTYPE_PURE_VIRTUALS (type)); |
| } |
| |
| SET_BINFO_MARKED (binfo); |
| |
| return NULL_TREE; |
| } |
| |
| /* Set CLASSTYPE_PURE_VIRTUALS for TYPE. */ |
| |
| void |
| get_pure_virtuals (type) |
| tree type; |
| { |
| tree vbases; |
| |
| /* Clear the CLASSTYPE_PURE_VIRTUALS list; whatever is already there |
| is going to be overridden. */ |
| CLASSTYPE_PURE_VIRTUALS (type) = NULL_TREE; |
| /* Now, run through all the bases which are not primary bases, and |
| collect the pure virtual functions. We look at the vtable in |
| each class to determine what pure virtual functions are present. |
| (A primary base is not interesting because the derived class of |
| which it is a primary base will contain vtable entries for the |
| pure virtuals in the base class. */ |
| dfs_walk (TYPE_BINFO (type), dfs_get_pure_virtuals, |
| dfs_unmarked_real_bases_queue_p, type); |
| dfs_walk (TYPE_BINFO (type), dfs_unmark, |
| dfs_marked_real_bases_queue_p, type); |
| |
| /* Put the pure virtuals in dfs order. */ |
| CLASSTYPE_PURE_VIRTUALS (type) = nreverse (CLASSTYPE_PURE_VIRTUALS (type)); |
| |
| for (vbases = CLASSTYPE_VBASECLASSES (type); |
| vbases; |
| vbases = TREE_CHAIN (vbases)) |
| { |
| tree virtuals; |
| |
| for (virtuals = BINFO_VIRTUALS (TREE_VALUE (vbases)); |
| virtuals; |
| virtuals = TREE_CHAIN (virtuals)) |
| { |
| tree base_fndecl = BV_FN (virtuals); |
| if (DECL_NEEDS_FINAL_OVERRIDER_P (base_fndecl)) |
| cp_error ("`%#D' needs a final overrider", base_fndecl); |
| } |
| } |
| } |
| |
| /* DEPTH-FIRST SEARCH ROUTINES. */ |
| |
| tree |
| markedp (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| return BINFO_MARKED (binfo) ? binfo : NULL_TREE; |
| } |
| |
| tree |
| unmarkedp (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| return !BINFO_MARKED (binfo) ? binfo : NULL_TREE; |
| } |
| |
| tree |
| marked_vtable_pathp (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| return BINFO_VTABLE_PATH_MARKED (binfo) ? binfo : NULL_TREE; |
| } |
| |
| tree |
| unmarked_vtable_pathp (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| return !BINFO_VTABLE_PATH_MARKED (binfo) ? binfo : NULL_TREE; |
| } |
| |
| static tree |
| marked_pushdecls_p (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| return (CLASS_TYPE_P (BINFO_TYPE (binfo)) |
| && BINFO_PUSHDECLS_MARKED (binfo)) ? binfo : NULL_TREE; |
| } |
| |
| static tree |
| unmarked_pushdecls_p (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| return (CLASS_TYPE_P (BINFO_TYPE (binfo)) |
| && !BINFO_PUSHDECLS_MARKED (binfo)) ? binfo : NULL_TREE; |
| } |
| |
| /* The worker functions for `dfs_walk'. These do not need to |
| test anything (vis a vis marking) if they are paired with |
| a predicate function (above). */ |
| |
| tree |
| dfs_unmark (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| CLEAR_BINFO_MARKED (binfo); |
| return NULL_TREE; |
| } |
| |
| |
| static tree |
| dfs_init_vbase_pointers (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| struct vbase_info *vi = (struct vbase_info *) data; |
| tree type = BINFO_TYPE (binfo); |
| tree fields; |
| tree this_vbase_ptr; |
| |
| /* Don't initialize the same base more than once. */ |
| SET_BINFO_VTABLE_PATH_MARKED (binfo); |
| |
| /* We know that VI->DECL_PTR points to the complete object. So, |
| finding a pointer to this subobject is easy. */ |
| this_vbase_ptr = build (PLUS_EXPR, |
| build_pointer_type (type), |
| vi->decl_ptr, |
| BINFO_OFFSET (binfo)); |
| |
| /* We're going to iterate through all the pointers to virtual |
| base-classes. They come at the beginning of the class. */ |
| fields = TYPE_FIELDS (type); |
| |
| if (fields == NULL_TREE |
| || DECL_NAME (fields) == NULL_TREE |
| || ! VBASE_NAME_P (DECL_NAME (fields))) |
| return NULL_TREE; |
| |
| if (build_pointer_type (type) |
| != TYPE_MAIN_VARIANT (TREE_TYPE (this_vbase_ptr))) |
| my_friendly_abort (125); |
| |
| while (fields && DECL_NAME (fields) && VBASE_NAME_P (DECL_NAME (fields))) |
| { |
| tree ref = build (COMPONENT_REF, TREE_TYPE (fields), |
| build_indirect_ref (this_vbase_ptr, NULL_PTR), fields); |
| tree init; |
| tree vbase_type; |
| tree vbase_binfo; |
| |
| vbase_type = TREE_TYPE (TREE_TYPE (fields)); |
| vbase_binfo = binfo_for_vbase (vbase_type, vi->type); |
| init = build (PLUS_EXPR, |
| build_pointer_type (vbase_type), |
| vi->decl_ptr, |
| BINFO_OFFSET (vbase_binfo)); |
| vi->inits |
| = tree_cons (vbase_binfo, |
| build_modify_expr (ref, NOP_EXPR, init), |
| vi->inits); |
| fields = TREE_CHAIN (fields); |
| } |
| |
| return NULL_TREE; |
| } |
| |
| /* Call CLEAR_BINFO_VTABLE_PATH_MARKED for BINFO. */ |
| |
| static tree |
| dfs_vtable_path_unmark (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| CLEAR_BINFO_VTABLE_PATH_MARKED (binfo); |
| return NULL_TREE; |
| } |
| |
| tree |
| init_vbase_pointers (type, decl_ptr) |
| tree type; |
| tree decl_ptr; |
| { |
| my_friendly_assert (!vbase_offsets_in_vtable_p (), 20000516); |
| |
| if (TYPE_USES_VIRTUAL_BASECLASSES (type)) |
| { |
| struct vbase_info vi; |
| tree binfo = TYPE_BINFO (type); |
| |
| /* Find all the virtual base classes, marking them for later |
| initialization. */ |
| vi.type = type; |
| vi.decl_ptr = decl_ptr; |
| vi.inits = NULL_TREE; |
| |
| /* Build up a list of the initializers. */ |
| dfs_walk_real (binfo, |
| dfs_init_vbase_pointers, 0, |
| unmarked_vtable_pathp, |
| &vi); |
| dfs_walk (binfo, |
| dfs_vtable_path_unmark, |
| marked_vtable_pathp, |
| NULL); |
| |
| return vi.inits; |
| } |
| |
| return 0; |
| } |
| |
| /* get the virtual context (the vbase that directly contains the |
| DECL_CONTEXT of the FNDECL) that the given FNDECL is declared in, |
| or NULL_TREE if there is none. |
| |
| FNDECL must come from a virtual table from a virtual base to ensure |
| that there is only one possible DECL_CONTEXT. |
| |
| We know that if there is more than one place (binfo) the fndecl that the |
| declared, they all refer to the same binfo. See get_class_offset_1 for |
| the check that ensures this. */ |
| |
| static tree |
| virtual_context (fndecl, t, vbase) |
| tree fndecl, t, vbase; |
| { |
| tree path; |
| if (get_base_distance (DECL_CONTEXT (fndecl), t, 0, &path) < 0) |
| { |
| /* DECL_CONTEXT can be ambiguous in t. */ |
| if (get_base_distance (DECL_CONTEXT (fndecl), vbase, 0, &path) >= 0) |
| { |
| while (path) |
| { |
| /* Not sure if checking path == vbase is necessary here, but just in |
| case it is. */ |
| if (TREE_VIA_VIRTUAL (path) || path == vbase) |
| return binfo_for_vbase (BINFO_TYPE (path), t); |
| path = BINFO_INHERITANCE_CHAIN (path); |
| } |
| } |
| /* This shouldn't happen, I don't want errors! */ |
| warning ("recoverable compiler error, fixups for virtual function"); |
| return vbase; |
| } |
| while (path) |
| { |
| if (TREE_VIA_VIRTUAL (path)) |
| return binfo_for_vbase (BINFO_TYPE (path), t); |
| path = BINFO_INHERITANCE_CHAIN (path); |
| } |
| return 0; |
| } |
| |
| /* Fixups upcast offsets for one vtable. |
| Entries may stay within the VBASE given, or |
| they may upcast into a direct base, or |
| they may upcast into a different vbase. |
| |
| We only need to do fixups in case 2 and 3. In case 2, we add in |
| the virtual base offset to effect an upcast, in case 3, we add in |
| the virtual base offset to effect an upcast, then subtract out the |
| offset for the other virtual base, to effect a downcast into it. |
| |
| This routine mirrors fixup_vtable_deltas in functionality, though |
| this one is runtime based, and the other is compile time based. |
| Conceivably that routine could be removed entirely, and all fixups |
| done at runtime. |
| |
| VBASE_OFFSETS is an association list of virtual bases that contains |
| offset information for the virtual bases, so the offsets are only |
| calculated once. */ |
| |
| static void |
| expand_upcast_fixups (binfo, addr, orig_addr, vbase, vbase_addr, t, |
| vbase_offsets) |
| tree binfo, addr, orig_addr, vbase, vbase_addr, t, *vbase_offsets; |
| { |
| tree virtuals; |
| tree vc; |
| tree delta; |
| HOST_WIDE_INT n; |
| |
| while (BINFO_PRIMARY_P (binfo)) |
| { |
| binfo = BINFO_INHERITANCE_CHAIN (binfo); |
| if (TREE_VIA_VIRTUAL (binfo)) |
| return; |
| } |
| |
| delta = purpose_member (vbase, *vbase_offsets); |
| if (! delta) |
| { |
| delta = build (PLUS_EXPR, |
| build_pointer_type (BINFO_TYPE (vbase)), |
| orig_addr, |
| BINFO_OFFSET (vbase)); |
| delta = build (MINUS_EXPR, ptrdiff_type_node, delta, vbase_addr); |
| delta = save_expr (delta); |
| delta = tree_cons (vbase, delta, *vbase_offsets); |
| *vbase_offsets = delta; |
| } |
| |
| for (virtuals = BINFO_VIRTUALS (binfo), n = 0; |
| virtuals; |
| virtuals = TREE_CHAIN (virtuals), ++n) |
| { |
| tree current_fndecl = TREE_VALUE (virtuals); |
| |
| if (current_fndecl |
| && current_fndecl != abort_fndecl |
| && (vc=virtual_context (current_fndecl, t, vbase)) != vbase) |
| { |
| /* This may in fact need a runtime fixup. */ |
| tree idx = build_int_2 (n, 0); |
| tree vtbl = BINFO_VTABLE (binfo); |
| tree nvtbl = lookup_name (DECL_NAME (vtbl), 0); |
| tree aref, ref, naref; |
| tree old_delta, new_delta; |
| tree init; |
| |
| if (nvtbl == NULL_TREE |
| || nvtbl == IDENTIFIER_GLOBAL_VALUE (DECL_NAME (vtbl))) |
| { |
| /* Dup it if it isn't in local scope yet. */ |
| nvtbl = build_decl |
| (VAR_DECL, DECL_NAME (vtbl), |
| TYPE_MAIN_VARIANT (TREE_TYPE (vtbl))); |
| DECL_ALIGN (nvtbl) = MAX (TYPE_ALIGN (double_type_node), |
| DECL_ALIGN (nvtbl)); |
| TREE_READONLY (nvtbl) = 0; |
| DECL_ARTIFICIAL (nvtbl) = 1; |
| nvtbl = pushdecl (nvtbl); |
| init = NULL_TREE; |
| cp_finish_decl (nvtbl, init, NULL_TREE, |
| LOOKUP_ONLYCONVERTING); |
| |
| /* We don't set DECL_VIRTUAL_P and DECL_CONTEXT on nvtbl |
| because they wouldn't be useful; everything that wants to |
| look at the vtable will look at the decl for the normal |
| vtable. Setting DECL_CONTEXT also screws up |
| decl_function_context. */ |
| |
| init = build (MODIFY_EXPR, TREE_TYPE (nvtbl), |
| nvtbl, vtbl); |
| finish_expr_stmt (init); |
| /* Update the vtable pointers as necessary. */ |
| ref = build_vfield_ref |
| (build_indirect_ref (addr, NULL_PTR), |
| DECL_CONTEXT (TYPE_VFIELD (BINFO_TYPE (binfo)))); |
| finish_expr_stmt |
| (build_modify_expr (ref, NOP_EXPR, nvtbl)); |
| } |
| assemble_external (vtbl); |
| aref = build_array_ref (vtbl, idx); |
| naref = build_array_ref (nvtbl, idx); |
| old_delta = build_component_ref (aref, delta_identifier, |
| NULL_TREE, 0); |
| new_delta = build_component_ref (naref, delta_identifier, |
| NULL_TREE, 0); |
| |
| /* This is a upcast, so we have to add the offset for the |
| virtual base. */ |
| old_delta = cp_build_binary_op (PLUS_EXPR, old_delta, |
| TREE_VALUE (delta)); |
| if (vc) |
| { |
| /* If this is set, we need to subtract out the delta |
| adjustments for the other virtual base that we |
| downcast into. */ |
| tree vc_delta = purpose_member (vc, *vbase_offsets); |
| if (! vc_delta) |
| { |
| tree vc_addr = convert_pointer_to_real (vc, orig_addr); |
| vc_delta = build (PLUS_EXPR, |
| build_pointer_type (BINFO_TYPE (vc)), |
| orig_addr, |
| BINFO_OFFSET (vc)); |
| vc_delta = build (MINUS_EXPR, ptrdiff_type_node, |
| vc_delta, vc_addr); |
| vc_delta = save_expr (vc_delta); |
| *vbase_offsets = tree_cons (vc, vc_delta, *vbase_offsets); |
| } |
| else |
| vc_delta = TREE_VALUE (vc_delta); |
| |
| /* This is a downcast, so we have to subtract the offset |
| for the virtual base. */ |
| old_delta = cp_build_binary_op (MINUS_EXPR, old_delta, vc_delta); |
| } |
| |
| TREE_READONLY (new_delta) = 0; |
| TREE_TYPE (new_delta) = |
| cp_build_qualified_type (TREE_TYPE (new_delta), |
| CP_TYPE_QUALS (TREE_TYPE (new_delta)) |
| & ~TYPE_QUAL_CONST); |
| finish_expr_stmt (build_modify_expr (new_delta, NOP_EXPR, |
| old_delta)); |
| } |
| } |
| } |
| |
| /* Fixup upcast offsets for all direct vtables. Patterned after |
| expand_direct_vtbls_init. */ |
| |
| static void |
| fixup_virtual_upcast_offsets (real_binfo, binfo, init_self, can_elide, addr, orig_addr, type, vbase, vbase_offsets) |
| tree real_binfo, binfo; |
| int init_self, can_elide; |
| tree addr, orig_addr, type, vbase, *vbase_offsets; |
| { |
| tree real_binfos = BINFO_BASETYPES (real_binfo); |
| tree binfos = BINFO_BASETYPES (binfo); |
| int i, n_baselinks = real_binfos ? TREE_VEC_LENGTH (real_binfos) : 0; |
| |
| for (i = 0; i < n_baselinks; i++) |
| { |
| tree real_base_binfo = TREE_VEC_ELT (real_binfos, i); |
| tree base_binfo = TREE_VEC_ELT (binfos, i); |
| int is_not_base_vtable |
| = !BINFO_PRIMARY_P (real_base_binfo); |
| if (! TREE_VIA_VIRTUAL (real_base_binfo)) |
| fixup_virtual_upcast_offsets (real_base_binfo, base_binfo, |
| is_not_base_vtable, can_elide, addr, |
| orig_addr, type, vbase, vbase_offsets); |
| } |
| #if 0 |
| /* Before turning this on, make sure it is correct. */ |
| if (can_elide && ! BINFO_MODIFIED (binfo)) |
| return; |
| #endif |
| /* Should we use something besides CLASSTYPE_VFIELDS? */ |
| if (init_self && CLASSTYPE_VFIELDS (BINFO_TYPE (real_binfo))) |
| { |
| tree new_addr = convert_pointer_to_real (binfo, addr); |
| expand_upcast_fixups (real_binfo, new_addr, orig_addr, vbase, addr, |
| type, vbase_offsets); |
| } |
| } |
| |
| /* Fixup all the virtual upcast offsets for TYPE. DECL_PTR is the |
| address of the sub-object being initialized. */ |
| |
| void |
| fixup_all_virtual_upcast_offsets (decl_ptr) |
| tree decl_ptr; |
| { |
| tree if_stmt; |
| tree in_charge_node; |
| tree vbases; |
| tree type; |
| |
| /* Only tweak the vtables if we're in charge. */ |
| in_charge_node = current_in_charge_parm; |
| if (!in_charge_node) |
| /* There's no need for any fixups in this case. */ |
| return; |
| in_charge_node = cp_build_binary_op (EQ_EXPR, |
| in_charge_node, integer_zero_node); |
| if_stmt = begin_if_stmt (); |
| finish_if_stmt_cond (in_charge_node, if_stmt); |
| |
| /* Iterate through the virtual bases, fixing up the upcast offset |
| for each one. */ |
| type = TREE_TYPE (TREE_TYPE (decl_ptr)); |
| for (vbases = CLASSTYPE_VBASECLASSES (type); |
| vbases; |
| vbases = TREE_CHAIN (vbases)) |
| { |
| if (flag_vtable_thunks) |
| /* We don't have dynamic thunks yet! So for now, just fail |
| silently. */ |
| ; |
| else |
| { |
| tree vbase; |
| tree vbase_offsets; |
| tree addr; |
| |
| vbase = find_vbase_instance (TREE_PURPOSE (vbases), type); |
| vbase_offsets = NULL_TREE; |
| addr = convert_pointer_to_vbase (TREE_PURPOSE (vbases), decl_ptr); |
| fixup_virtual_upcast_offsets (vbase, |
| TYPE_BINFO (TREE_PURPOSE (vbases)), |
| 1, 0, addr, decl_ptr, |
| type, vbase, &vbase_offsets); |
| } |
| } |
| |
| /* Close out the if-statement. */ |
| finish_then_clause (if_stmt); |
| finish_if_stmt (); |
| } |
| |
| /* get virtual base class types. |
| This adds type to the vbase_types list in reverse dfs order. |
| Ordering is very important, so don't change it. */ |
| |
| static tree |
| dfs_get_vbase_types (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| tree type = (tree) data; |
| |
| if (TREE_VIA_VIRTUAL (binfo)) |
| CLASSTYPE_VBASECLASSES (type) |
| = tree_cons (BINFO_TYPE (binfo), |
| binfo, |
| CLASSTYPE_VBASECLASSES (type)); |
| SET_BINFO_MARKED (binfo); |
| return NULL_TREE; |
| } |
| |
| /* Called via dfs_walk from mark_primary_bases. Builds the |
| inheritance graph order list of BINFOs. */ |
| |
| static tree |
| dfs_build_inheritance_graph_order (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| tree *last_binfo = (tree *) data; |
| |
| if (*last_binfo) |
| TREE_CHAIN (*last_binfo) = binfo; |
| *last_binfo = binfo; |
| SET_BINFO_MARKED (binfo); |
| return NULL_TREE; |
| } |
| |
| /* Set CLASSTYPE_VBASECLASSES for TYPE. */ |
| |
| void |
| get_vbase_types (type) |
| tree type; |
| { |
| tree last_binfo; |
| |
| CLASSTYPE_VBASECLASSES (type) = NULL_TREE; |
| dfs_walk (TYPE_BINFO (type), dfs_get_vbase_types, unmarkedp, type); |
| /* Rely upon the reverse dfs ordering from dfs_get_vbase_types, and now |
| reverse it so that we get normal dfs ordering. */ |
| CLASSTYPE_VBASECLASSES (type) = nreverse (CLASSTYPE_VBASECLASSES (type)); |
| dfs_walk (TYPE_BINFO (type), dfs_unmark, markedp, 0); |
| /* Thread the BINFOs in inheritance-graph order. */ |
| last_binfo = NULL; |
| dfs_walk_real (TYPE_BINFO (type), |
| dfs_build_inheritance_graph_order, |
| NULL, |
| unmarkedp, |
| &last_binfo); |
| dfs_walk (TYPE_BINFO (type), dfs_unmark, markedp, NULL); |
| } |
| |
| /* Called from find_vbase_instance via dfs_walk. */ |
| |
| static tree |
| dfs_find_vbase_instance (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| tree base = TREE_VALUE ((tree) data); |
| |
| if (BINFO_PRIMARY_P (binfo) |
| && same_type_p (BINFO_TYPE (binfo), base)) |
| return binfo; |
| |
| return NULL_TREE; |
| } |
| |
| /* Find the real occurrence of the virtual BASE (a class type) in the |
| hierarchy dominated by TYPE. */ |
| |
| tree |
| find_vbase_instance (base, type) |
| tree base; |
| tree type; |
| { |
| tree instance; |
| |
| instance = binfo_for_vbase (base, type); |
| if (!BINFO_PRIMARY_P (instance)) |
| return instance; |
| |
| return dfs_walk (TYPE_BINFO (type), |
| dfs_find_vbase_instance, |
| NULL, |
| build_tree_list (type, base)); |
| } |
| |
| |
| /* Debug info for C++ classes can get very large; try to avoid |
| emitting it everywhere. |
| |
| Note that this optimization wins even when the target supports |
| BINCL (if only slightly), and reduces the amount of work for the |
| linker. */ |
| |
| void |
| maybe_suppress_debug_info (t) |
| tree t; |
| { |
| /* We can't do the usual TYPE_DECL_SUPPRESS_DEBUG thing with DWARF, which |
| does not support name references between translation units. It supports |
| symbolic references between translation units, but only within a single |
| executable or shared library. |
| |
| For DWARF 2, we handle TYPE_DECL_SUPPRESS_DEBUG by pretending |
| that the type was never defined, so we only get the members we |
| actually define. */ |
| if (write_symbols == DWARF_DEBUG || write_symbols == NO_DEBUG) |
| return; |
| |
| /* We might have set this earlier in cp_finish_decl. */ |
| TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 0; |
| |
| /* If we already know how we're handling this class, handle debug info |
| the same way. */ |
| if (CLASSTYPE_INTERFACE_KNOWN (t)) |
| { |
| if (CLASSTYPE_INTERFACE_ONLY (t)) |
| TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 1; |
| /* else don't set it. */ |
| } |
| /* If the class has a vtable, write out the debug info along with |
| the vtable. */ |
| else if (TYPE_CONTAINS_VPTR_P (t)) |
| TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 1; |
| |
| /* Otherwise, just emit the debug info normally. */ |
| } |
| |
| /* Note that we want debugging information for a base class of a class |
| whose vtable is being emitted. Normally, this would happen because |
| calling the constructor for a derived class implies calling the |
| constructors for all bases, which involve initializing the |
| appropriate vptr with the vtable for the base class; but in the |
| presence of optimization, this initialization may be optimized |
| away, so we tell finish_vtable_vardecl that we want the debugging |
| information anyway. */ |
| |
| static tree |
| dfs_debug_mark (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| tree t = BINFO_TYPE (binfo); |
| |
| CLASSTYPE_DEBUG_REQUESTED (t) = 1; |
| |
| return NULL_TREE; |
| } |
| |
| /* Returns BINFO if we haven't already noted that we want debugging |
| info for this base class. */ |
| |
| static tree |
| dfs_debug_unmarkedp (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| return (!CLASSTYPE_DEBUG_REQUESTED (BINFO_TYPE (binfo)) |
| ? binfo : NULL_TREE); |
| } |
| |
| /* Write out the debugging information for TYPE, whose vtable is being |
| emitted. Also walk through our bases and note that we want to |
| write out information for them. This avoids the problem of not |
| writing any debug info for intermediate basetypes whose |
| constructors, and thus the references to their vtables, and thus |
| the vtables themselves, were optimized away. */ |
| |
| void |
| note_debug_info_needed (type) |
| tree type; |
| { |
| if (TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type))) |
| { |
| TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type)) = 0; |
| rest_of_type_compilation (type, toplevel_bindings_p ()); |
| } |
| |
| dfs_walk (TYPE_BINFO (type), dfs_debug_mark, dfs_debug_unmarkedp, 0); |
| } |
| |
| /* Subroutines of push_class_decls (). */ |
| |
| /* Returns 1 iff BINFO is a base we shouldn't really be able to see into, |
| because it (or one of the intermediate bases) depends on template parms. */ |
| |
| static int |
| dependent_base_p (binfo) |
| tree binfo; |
| { |
| for (; binfo; binfo = BINFO_INHERITANCE_CHAIN (binfo)) |
| { |
| if (currently_open_class (TREE_TYPE (binfo))) |
| break; |
| if (uses_template_parms (TREE_TYPE (binfo))) |
| return 1; |
| } |
| return 0; |
| } |
| |
| static void |
| setup_class_bindings (name, type_binding_p) |
| tree name; |
| int type_binding_p; |
| { |
| tree type_binding = NULL_TREE; |
| tree value_binding; |
| |
| /* If we've already done the lookup for this declaration, we're |
| done. */ |
| if (IDENTIFIER_CLASS_VALUE (name)) |
| return; |
| |
| /* First, deal with the type binding. */ |
| if (type_binding_p) |
| { |
| type_binding = lookup_member (current_class_type, name, |
| /*protect=*/2, |
| /*want_type=*/1); |
| if (TREE_CODE (type_binding) == TREE_LIST |
| && TREE_TYPE (type_binding) == error_mark_node) |
| /* NAME is ambiguous. */ |
| push_class_level_binding (name, type_binding); |
| else |
| pushdecl_class_level (type_binding); |
| } |
| |
| /* Now, do the value binding. */ |
| value_binding = lookup_member (current_class_type, name, |
| /*protect=*/2, |
| /*want_type=*/0); |
| |
| if (type_binding_p |
| && (TREE_CODE (value_binding) == TYPE_DECL |
| || (TREE_CODE (value_binding) == TREE_LIST |
| && TREE_TYPE (value_binding) == error_mark_node |
| && (TREE_CODE (TREE_VALUE (value_binding)) |
| == TYPE_DECL)))) |
| /* We found a type-binding, even when looking for a non-type |
| binding. This means that we already processed this binding |
| above. */ |
| my_friendly_assert (type_binding_p, 19990401); |
| else if (value_binding) |
| { |
| if (TREE_CODE (value_binding) == TREE_LIST |
| && TREE_TYPE (value_binding) == error_mark_node) |
| /* NAME is ambiguous. */ |
| push_class_level_binding (name, value_binding); |
| else |
| { |
| if (BASELINK_P (value_binding)) |
| /* NAME is some overloaded functions. */ |
| value_binding = TREE_VALUE (value_binding); |
| pushdecl_class_level (value_binding); |
| } |
| } |
| } |
| |
| /* Push class-level declarations for any names appearing in BINFO that |
| are TYPE_DECLS. */ |
| |
| static tree |
| dfs_push_type_decls (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| tree type; |
| tree fields; |
| |
| type = BINFO_TYPE (binfo); |
| for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields)) |
| if (DECL_NAME (fields) && TREE_CODE (fields) == TYPE_DECL |
| && !(!same_type_p (type, current_class_type) |
| && template_self_reference_p (type, fields))) |
| setup_class_bindings (DECL_NAME (fields), /*type_binding_p=*/1); |
| |
| /* We can't just use BINFO_MARKED because envelope_add_decl uses |
| DERIVED_FROM_P, which calls get_base_distance. */ |
| SET_BINFO_PUSHDECLS_MARKED (binfo); |
| |
| return NULL_TREE; |
| } |
| |
| /* Push class-level declarations for any names appearing in BINFO that |
| are not TYPE_DECLS. */ |
| |
| static tree |
| dfs_push_decls (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| tree type; |
| tree method_vec; |
| int dep_base_p; |
| |
| type = BINFO_TYPE (binfo); |
| dep_base_p = (processing_template_decl && type != current_class_type |
| && dependent_base_p (binfo)); |
| if (!dep_base_p) |
| { |
| tree fields; |
| for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields)) |
| if (DECL_NAME (fields) |
| && TREE_CODE (fields) != TYPE_DECL |
| && TREE_CODE (fields) != USING_DECL) |
| setup_class_bindings (DECL_NAME (fields), /*type_binding_p=*/0); |
| else if (TREE_CODE (fields) == FIELD_DECL |
| && ANON_AGGR_TYPE_P (TREE_TYPE (fields))) |
| dfs_push_decls (TYPE_BINFO (TREE_TYPE (fields)), data); |
| |
| method_vec = (CLASS_TYPE_P (type) |
| ? CLASSTYPE_METHOD_VEC (type) : NULL_TREE); |
| if (method_vec) |
| { |
| tree *methods; |
| tree *end; |
| |
| /* Farm out constructors and destructors. */ |
| end = TREE_VEC_END (method_vec); |
| |
| for (methods = &TREE_VEC_ELT (method_vec, 2); |
| *methods && methods != end; |
| methods++) |
| setup_class_bindings (DECL_NAME (OVL_CURRENT (*methods)), |
| /*type_binding_p=*/0); |
| } |
| } |
| |
| CLEAR_BINFO_PUSHDECLS_MARKED (binfo); |
| |
| return NULL_TREE; |
| } |
| |
| /* When entering the scope of a class, we cache all of the |
| fields that that class provides within its inheritance |
| lattice. Where ambiguities result, we mark them |
| with `error_mark_node' so that if they are encountered |
| without explicit qualification, we can emit an error |
| message. */ |
| |
| void |
| push_class_decls (type) |
| tree type; |
| { |
| search_stack = push_search_level (search_stack, &search_obstack); |
| |
| /* Enter type declarations and mark. */ |
| dfs_walk (TYPE_BINFO (type), dfs_push_type_decls, unmarked_pushdecls_p, 0); |
| |
| /* Enter non-type declarations and unmark. */ |
| dfs_walk (TYPE_BINFO (type), dfs_push_decls, marked_pushdecls_p, 0); |
| } |
| |
| /* Here's a subroutine we need because C lacks lambdas. */ |
| |
| static tree |
| dfs_unuse_fields (binfo, data) |
| tree binfo; |
| void *data ATTRIBUTE_UNUSED; |
| { |
| tree type = TREE_TYPE (binfo); |
| tree fields; |
| |
| for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields)) |
| { |
| if (TREE_CODE (fields) != FIELD_DECL) |
| continue; |
| |
| TREE_USED (fields) = 0; |
| if (DECL_NAME (fields) == NULL_TREE |
| && ANON_AGGR_TYPE_P (TREE_TYPE (fields))) |
| unuse_fields (TREE_TYPE (fields)); |
| } |
| |
| return NULL_TREE; |
| } |
| |
| void |
| unuse_fields (type) |
| tree type; |
| { |
| dfs_walk (TYPE_BINFO (type), dfs_unuse_fields, unmarkedp, 0); |
| } |
| |
| void |
| pop_class_decls () |
| { |
| /* We haven't pushed a search level when dealing with cached classes, |
| so we'd better not try to pop it. */ |
| if (search_stack) |
| search_stack = pop_search_level (search_stack); |
| } |
| |
| void |
| print_search_statistics () |
| { |
| #ifdef GATHER_STATISTICS |
| fprintf (stderr, "%d fields searched in %d[%d] calls to lookup_field[_1]\n", |
| n_fields_searched, n_calls_lookup_field, n_calls_lookup_field_1); |
| fprintf (stderr, "%d fnfields searched in %d calls to lookup_fnfields\n", |
| n_outer_fields_searched, n_calls_lookup_fnfields); |
| fprintf (stderr, "%d calls to get_base_type\n", n_calls_get_base_type); |
| #else /* GATHER_STATISTICS */ |
| fprintf (stderr, "no search statistics\n"); |
| #endif /* GATHER_STATISTICS */ |
| } |
| |
| void |
| init_search_processing () |
| { |
| gcc_obstack_init (&search_obstack); |
| } |
| |
| void |
| reinit_search_statistics () |
| { |
| #ifdef GATHER_STATISTICS |
| n_fields_searched = 0; |
| n_calls_lookup_field = 0, n_calls_lookup_field_1 = 0; |
| n_calls_lookup_fnfields = 0, n_calls_lookup_fnfields_1 = 0; |
| n_calls_get_base_type = 0; |
| n_outer_fields_searched = 0; |
| n_contexts_saved = 0; |
| #endif /* GATHER_STATISTICS */ |
| } |
| |
| static tree |
| add_conversions (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| int i; |
| tree method_vec = CLASSTYPE_METHOD_VEC (BINFO_TYPE (binfo)); |
| tree *conversions = (tree *) data; |
| |
| /* Some builtin types have no method vector, not even an empty one. */ |
| if (!method_vec) |
| return NULL_TREE; |
| |
| for (i = 2; i < TREE_VEC_LENGTH (method_vec); ++i) |
| { |
| tree tmp = TREE_VEC_ELT (method_vec, i); |
| tree name; |
| |
| if (!tmp || ! DECL_CONV_FN_P (OVL_CURRENT (tmp))) |
| break; |
| |
| name = DECL_NAME (OVL_CURRENT (tmp)); |
| |
| /* Make sure we don't already have this conversion. */ |
| if (! IDENTIFIER_MARKED (name)) |
| { |
| *conversions = tree_cons (binfo, tmp, *conversions); |
| IDENTIFIER_MARKED (name) = 1; |
| } |
| } |
| return NULL_TREE; |
| } |
| |
| /* Return a TREE_LIST containing all the non-hidden user-defined |
| conversion functions for TYPE (and its base-classes). The |
| TREE_VALUE of each node is a FUNCTION_DECL or an OVERLOAD |
| containing the conversion functions. The TREE_PURPOSE is the BINFO |
| from which the conversion functions in this node were selected. */ |
| |
| tree |
| lookup_conversions (type) |
| tree type; |
| { |
| tree t; |
| tree conversions = NULL_TREE; |
| |
| if (COMPLETE_TYPE_P (type)) |
| bfs_walk (TYPE_BINFO (type), add_conversions, 0, &conversions); |
| |
| for (t = conversions; t; t = TREE_CHAIN (t)) |
| IDENTIFIER_MARKED (DECL_NAME (OVL_CURRENT (TREE_VALUE (t)))) = 0; |
| |
| return conversions; |
| } |
| |
| struct overlap_info |
| { |
| tree compare_type; |
| int found_overlap; |
| }; |
| |
| /* Check whether the empty class indicated by EMPTY_BINFO is also present |
| at offset 0 in COMPARE_TYPE, and set found_overlap if so. */ |
| |
| static tree |
| dfs_check_overlap (empty_binfo, data) |
| tree empty_binfo; |
| void *data; |
| { |
| struct overlap_info *oi = (struct overlap_info *) data; |
| tree binfo; |
| for (binfo = TYPE_BINFO (oi->compare_type); |
| ; |
| binfo = BINFO_BASETYPE (binfo, 0)) |
| { |
| if (BINFO_TYPE (binfo) == BINFO_TYPE (empty_binfo)) |
| { |
| oi->found_overlap = 1; |
| break; |
| } |
| else if (BINFO_BASETYPES (binfo) == NULL_TREE) |
| break; |
| } |
| |
| return NULL_TREE; |
| } |
| |
| /* Trivial function to stop base traversal when we find something. */ |
| |
| static tree |
| dfs_no_overlap_yet (binfo, data) |
| tree binfo; |
| void *data; |
| { |
| struct overlap_info *oi = (struct overlap_info *) data; |
| return !oi->found_overlap ? binfo : NULL_TREE; |
| } |
| |
| /* Returns nonzero if EMPTY_TYPE or any of its bases can also be found at |
| offset 0 in NEXT_TYPE. Used in laying out empty base class subobjects. */ |
| |
| int |
| types_overlap_p (empty_type, next_type) |
| tree empty_type, next_type; |
| { |
| struct overlap_info oi; |
| |
| if (! IS_AGGR_TYPE (next_type)) |
| return 0; |
| oi.compare_type = next_type; |
| oi.found_overlap = 0; |
| dfs_walk (TYPE_BINFO (empty_type), dfs_check_overlap, |
| dfs_no_overlap_yet, &oi); |
| return oi.found_overlap; |
| } |
| |
| /* Given a vtable VAR, determine which of the inherited classes the vtable |
| inherits (in a loose sense) functions from. |
| |
| FIXME: This does not work with the new ABI. */ |
| |
| tree |
| binfo_for_vtable (var) |
| tree var; |
| { |
| tree main_binfo = TYPE_BINFO (DECL_CONTEXT (var)); |
| tree binfos = TYPE_BINFO_BASETYPES (BINFO_TYPE (main_binfo)); |
| int n_baseclasses = CLASSTYPE_N_BASECLASSES (BINFO_TYPE (main_binfo)); |
| int i; |
| |
| for (i = 0; i < n_baseclasses; i++) |
| { |
| tree base_binfo = TREE_VEC_ELT (binfos, i); |
| if (base_binfo != NULL_TREE && BINFO_VTABLE (base_binfo) == var) |
| return base_binfo; |
| } |
| |
| /* If no secondary base classes matched, return the primary base, if |
| there is one. */ |
| if (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (main_binfo))) |
| return get_primary_binfo (main_binfo); |
| |
| return main_binfo; |
| } |
| |
| /* Returns the binfo of the first direct or indirect virtual base derived |
| from BINFO, or NULL if binfo is not via virtual. */ |
| |
| tree |
| binfo_from_vbase (binfo) |
| tree binfo; |
| { |
| for (; binfo; binfo = BINFO_INHERITANCE_CHAIN (binfo)) |
| { |
| if (TREE_VIA_VIRTUAL (binfo)) |
| return binfo; |
| } |
| return NULL_TREE; |
| } |
| |
| /* Returns the binfo of the first direct or indirect virtual base derived |
| from BINFO up to the TREE_TYPE, LIMIT, or NULL if binfo is not |
| via virtual. */ |
| |
| tree |
| binfo_via_virtual (binfo, limit) |
| tree binfo; |
| tree limit; |
| { |
| for (; binfo && (!limit || !same_type_p (BINFO_TYPE (binfo), limit)); |
| binfo = BINFO_INHERITANCE_CHAIN (binfo)) |
| { |
| if (TREE_VIA_VIRTUAL (binfo)) |
| return binfo; |
| } |
| return NULL_TREE; |
| } |
| |
| /* Returns the BINFO (if any) for the virtual baseclass T of the class |
| C from the CLASSTYPE_VBASECLASSES list. */ |
| |
| tree |
| binfo_for_vbase (basetype, classtype) |
| tree basetype; |
| tree classtype; |
| { |
| tree binfo; |
| |
| binfo = purpose_member (basetype, CLASSTYPE_VBASECLASSES (classtype)); |
| return binfo ? TREE_VALUE (binfo) : NULL_TREE; |
| } |