1136 lines
32 KiB
C
1136 lines
32 KiB
C
/* RunTime Type Identification
|
||
Copyright (C) 1995, 1996 Free Software Foundation, Inc.
|
||
Mostly written by Jason Merrill (jason@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. */
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||
|
||
|
||
#include "config.h"
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#include "system.h"
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#include "tree.h"
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||
#include "cp-tree.h"
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||
#include "flags.h"
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||
#include "output.h"
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#include "assert.h"
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#include "toplev.h"
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#ifndef INT_TYPE_SIZE
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#define INT_TYPE_SIZE BITS_PER_WORD
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#endif
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||
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||
extern struct obstack permanent_obstack;
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||
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||
static tree call_void_fn PROTO((char *));
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||
static tree build_headof_sub PROTO((tree));
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||
static tree build_headof PROTO((tree));
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static tree get_tinfo_var PROTO((tree));
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static tree get_typeid_1 PROTO((tree));
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static tree ifnonnull PROTO((tree, tree));
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||
static tree build_dynamic_cast_1 PROTO((tree, tree));
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||
static void expand_si_desc PROTO((tree, tree));
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||
static void expand_class_desc PROTO((tree, tree));
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||
static void expand_attr_desc PROTO((tree, tree));
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||
static void expand_ptr_desc PROTO((tree, tree));
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static void expand_generic_desc PROTO((tree, tree, char *));
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static tree throw_bad_cast PROTO((void));
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static tree throw_bad_typeid PROTO((void));
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||
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tree type_info_type_node;
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||
tree tinfo_fn_id;
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||
tree tinfo_fn_type;
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||
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||
void
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||
init_rtti_processing ()
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||
{
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||
if (flag_honor_std)
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push_namespace (get_identifier ("std"));
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type_info_type_node = xref_tag
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(class_type_node, get_identifier ("type_info"), NULL_TREE, 1);
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if (flag_honor_std)
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pop_namespace ();
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||
tinfo_fn_id = get_identifier ("__tf");
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tinfo_fn_type = build_function_type
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(build_reference_type (build_type_variant (type_info_type_node, 1, 0)),
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void_list_node);
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}
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/* Given a pointer to an object with at least one virtual table
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||
pointer somewhere, return a pointer to a possible sub-object that
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has a virtual table pointer in it that is the vtable parent for
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that sub-object. */
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static tree
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build_headof_sub (exp)
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tree exp;
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{
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tree type = TREE_TYPE (TREE_TYPE (exp));
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tree basetype = CLASSTYPE_RTTI (type);
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tree binfo = get_binfo (basetype, type, 0);
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exp = convert_pointer_to_real (binfo, exp);
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return exp;
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}
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/* Given the expression EXP of type `class *', return the head of the
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object pointed to by EXP with type cv void*, if the class has any
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virtual functions (TYPE_VIRTUAL_P), else just return the
|
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expression. */
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static tree
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build_headof (exp)
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tree exp;
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{
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tree type = TREE_TYPE (exp);
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tree aref;
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||
tree offset;
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||
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||
if (TREE_CODE (type) != POINTER_TYPE)
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||
{
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||
error ("`headof' applied to non-pointer type");
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||
return error_mark_node;
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||
}
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type = TREE_TYPE (type);
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||
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if (!TYPE_VIRTUAL_P (type))
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return exp;
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||
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/* If we don't have rtti stuff, get to a sub-object that does. */
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||
if (!CLASSTYPE_VFIELDS (TREE_TYPE (TREE_TYPE (exp))))
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exp = build_headof_sub (exp);
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||
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||
/* We use this a couple of times below, protect it. */
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||
exp = save_expr (exp);
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aref = build_vtbl_ref (build_indirect_ref (exp, NULL_PTR), integer_zero_node);
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if (flag_vtable_thunks)
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offset = aref;
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else
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offset = build_component_ref (aref, delta_identifier, NULL_TREE, 0);
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||
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type = build_type_variant (ptr_type_node, TREE_READONLY (exp),
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TREE_THIS_VOLATILE (exp));
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||
return build (PLUS_EXPR, type, exp,
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cp_convert (ptrdiff_type_node, offset));
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||
}
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||
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||
/* Build a call to a generic entry point taking and returning void. */
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||
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||
static tree
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||
call_void_fn (name)
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||
char *name;
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||
{
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||
tree d = get_identifier (name);
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||
tree type;
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||
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||
if (IDENTIFIER_GLOBAL_VALUE (d))
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||
d = IDENTIFIER_GLOBAL_VALUE (d);
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||
else
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||
{
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push_obstacks (&permanent_obstack, &permanent_obstack);
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||
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||
type = build_function_type (void_type_node, void_list_node);
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d = build_lang_decl (FUNCTION_DECL, d, type);
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||
DECL_EXTERNAL (d) = 1;
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||
TREE_PUBLIC (d) = 1;
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||
DECL_ARTIFICIAL (d) = 1;
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pushdecl_top_level (d);
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||
make_function_rtl (d);
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assemble_external (d);
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pop_obstacks ();
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||
}
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||
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return build_call (d, void_type_node, NULL_TREE);
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}
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||
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||
/* Get a bad_cast node for the program to throw...
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See libstdc++/exception.cc for __throw_bad_cast */
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static tree
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||
throw_bad_cast ()
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{
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return call_void_fn ("__throw_bad_cast");
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||
}
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||
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static tree
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throw_bad_typeid ()
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{
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return call_void_fn ("__throw_bad_typeid");
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||
}
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||
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||
/* Return the type_info function associated with the expression EXP. If
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EXP is a reference to a polymorphic class, return the dynamic type;
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otherwise return the static type of the expression. */
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tree
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get_tinfo_fn_dynamic (exp)
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tree exp;
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||
{
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||
tree type;
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||
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if (exp == error_mark_node)
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||
return error_mark_node;
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||
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||
if (type_unknown_p (exp))
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||
{
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error ("typeid of overloaded function");
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||
return error_mark_node;
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||
}
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||
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type = TREE_TYPE (exp);
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||
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||
/* peel back references, so they match. */
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||
if (TREE_CODE (type) == REFERENCE_TYPE)
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type = TREE_TYPE (type);
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||
|
||
/* Peel off cv qualifiers. */
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||
type = TYPE_MAIN_VARIANT (type);
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||
|
||
/* If exp is a reference to polymorphic type, get the real type_info. */
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||
if (TYPE_VIRTUAL_P (type) && ! resolves_to_fixed_type_p (exp, 0))
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||
{
|
||
/* build reference to type_info from vtable. */
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||
tree t;
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||
|
||
if (! flag_rtti)
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||
{
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||
warning ("taking dynamic typeid of object without -frtti");
|
||
push_obstacks (&permanent_obstack, &permanent_obstack);
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||
init_rtti_processing ();
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||
pop_obstacks ();
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||
flag_rtti = 1;
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||
}
|
||
|
||
/* If we don't have rtti stuff, get to a sub-object that does. */
|
||
if (! CLASSTYPE_VFIELDS (type))
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||
{
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||
exp = build_unary_op (ADDR_EXPR, exp, 0);
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||
exp = build_headof_sub (exp);
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||
exp = build_indirect_ref (exp, NULL_PTR);
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||
}
|
||
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||
if (flag_vtable_thunks)
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||
t = build_vfn_ref ((tree *) 0, exp, integer_one_node);
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||
else
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||
t = build_vfn_ref ((tree *) 0, exp, integer_zero_node);
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||
TREE_TYPE (t) = build_pointer_type (tinfo_fn_type);
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||
return t;
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||
}
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||
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||
/* otherwise return the type_info for the static type of the expr. */
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||
return get_tinfo_fn (TYPE_MAIN_VARIANT (type));
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||
}
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||
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tree
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||
build_typeid (exp)
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||
tree exp;
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||
{
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||
exp = get_tinfo_fn_dynamic (exp);
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||
exp = build_call (exp, TREE_TYPE (tinfo_fn_type), NULL_TREE);
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||
return convert_from_reference (exp);
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||
}
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||
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||
tree
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||
build_x_typeid (exp)
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||
tree exp;
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||
{
|
||
tree cond = NULL_TREE;
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||
tree type = TREE_TYPE (tinfo_fn_type);
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||
int nonnull;
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||
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if (processing_template_decl)
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||
return build_min_nt (TYPEID_EXPR, exp);
|
||
|
||
if (TREE_CODE (exp) == INDIRECT_REF
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||
&& TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == POINTER_TYPE
|
||
&& TYPE_VIRTUAL_P (TREE_TYPE (exp))
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||
&& ! resolves_to_fixed_type_p (exp, &nonnull)
|
||
&& ! nonnull)
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||
{
|
||
exp = stabilize_reference (exp);
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||
cond = cp_convert (boolean_type_node, TREE_OPERAND (exp, 0));
|
||
}
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||
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exp = get_tinfo_fn_dynamic (exp);
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||
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if (exp == error_mark_node)
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||
return error_mark_node;
|
||
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||
exp = build_call (exp, type, NULL_TREE);
|
||
|
||
if (cond)
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||
{
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||
tree bad = throw_bad_typeid ();
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||
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||
bad = build_compound_expr
|
||
(expr_tree_cons (NULL_TREE, bad, build_expr_list
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||
(NULL_TREE, cp_convert (type, integer_zero_node))));
|
||
exp = build (COND_EXPR, type, cond, exp, bad);
|
||
}
|
||
|
||
return convert_from_reference (exp);
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||
}
|
||
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||
static tree
|
||
get_tinfo_var (type)
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||
tree type;
|
||
{
|
||
tree tname = build_overload_with_type (get_identifier ("__ti"), type);
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||
tree tdecl, arrtype;
|
||
int size;
|
||
|
||
if (IDENTIFIER_GLOBAL_VALUE (tname))
|
||
return IDENTIFIER_GLOBAL_VALUE (tname);
|
||
|
||
/* Figure out how much space we need to allocate for the type_info object.
|
||
If our struct layout or the type_info classes are changed, this will
|
||
need to be modified. */
|
||
if (TYPE_VOLATILE (type) || TYPE_READONLY (type))
|
||
size = 3 * POINTER_SIZE + INT_TYPE_SIZE;
|
||
else if (TREE_CODE (type) == POINTER_TYPE
|
||
&& ! (TREE_CODE (TREE_TYPE (type)) == OFFSET_TYPE
|
||
|| TREE_CODE (TREE_TYPE (type)) == METHOD_TYPE))
|
||
size = 3 * POINTER_SIZE;
|
||
else if (IS_AGGR_TYPE (type))
|
||
{
|
||
if (CLASSTYPE_N_BASECLASSES (type) == 0)
|
||
size = 2 * POINTER_SIZE;
|
||
else if (! TYPE_USES_COMPLEX_INHERITANCE (type)
|
||
&& (TREE_VIA_PUBLIC
|
||
(TREE_VEC_ELT (TYPE_BINFO_BASETYPES (type), 0))))
|
||
size = 3 * POINTER_SIZE;
|
||
else
|
||
size = 3 * POINTER_SIZE + TYPE_PRECISION (sizetype);
|
||
}
|
||
else
|
||
size = 2 * POINTER_SIZE;
|
||
|
||
push_obstacks (&permanent_obstack, &permanent_obstack);
|
||
|
||
/* The type for a character array of the appropriate size. */
|
||
arrtype = build_cplus_array_type
|
||
(unsigned_char_type_node,
|
||
build_index_type (size_int (size / BITS_PER_UNIT - 1)));
|
||
|
||
tdecl = build_decl (VAR_DECL, tname, arrtype);
|
||
TREE_PUBLIC (tdecl) = 1;
|
||
DECL_EXTERNAL (tdecl) = 1;
|
||
DECL_ARTIFICIAL (tdecl) = 1;
|
||
pushdecl_top_level (tdecl);
|
||
cp_finish_decl (tdecl, NULL_TREE, NULL_TREE, 0, 0);
|
||
|
||
pop_obstacks ();
|
||
|
||
return tdecl;
|
||
}
|
||
|
||
tree
|
||
get_tinfo_fn (type)
|
||
tree type;
|
||
{
|
||
tree name;
|
||
tree d;
|
||
|
||
if (TREE_CODE (type) == OFFSET_TYPE)
|
||
type = TREE_TYPE (type);
|
||
if (TREE_CODE (type) == METHOD_TYPE)
|
||
type = build_function_type (TREE_TYPE (type),
|
||
TREE_CHAIN (TYPE_ARG_TYPES (type)));
|
||
|
||
name = build_overload_with_type (tinfo_fn_id, type);
|
||
|
||
if (IDENTIFIER_GLOBAL_VALUE (name))
|
||
return IDENTIFIER_GLOBAL_VALUE (name);
|
||
|
||
push_obstacks (&permanent_obstack, &permanent_obstack);
|
||
|
||
d = build_lang_decl (FUNCTION_DECL, name, tinfo_fn_type);
|
||
DECL_EXTERNAL (d) = 1;
|
||
TREE_PUBLIC (d) = 1;
|
||
DECL_ARTIFICIAL (d) = 1;
|
||
DECL_NOT_REALLY_EXTERN (d) = 1;
|
||
DECL_MUTABLE_P (d) = 1;
|
||
TREE_TYPE (name) = copy_to_permanent (type);
|
||
|
||
pushdecl_top_level (d);
|
||
make_function_rtl (d);
|
||
assemble_external (d);
|
||
mark_inline_for_output (d);
|
||
pop_obstacks ();
|
||
|
||
return d;
|
||
}
|
||
|
||
static tree
|
||
get_typeid_1 (type)
|
||
tree type;
|
||
{
|
||
tree t = build_call
|
||
(get_tinfo_fn (type), TREE_TYPE (tinfo_fn_type), NULL_TREE);
|
||
return convert_from_reference (t);
|
||
}
|
||
|
||
/* Return the type_info object for TYPE, creating it if necessary. */
|
||
|
||
tree
|
||
get_typeid (type)
|
||
tree type;
|
||
{
|
||
if (type == error_mark_node)
|
||
return error_mark_node;
|
||
|
||
if (! flag_rtti)
|
||
{
|
||
warning ("requesting typeid of object without -frtti");
|
||
push_obstacks (&permanent_obstack, &permanent_obstack);
|
||
init_rtti_processing ();
|
||
pop_obstacks ();
|
||
flag_rtti = 1;
|
||
}
|
||
|
||
if (processing_template_decl)
|
||
return build_min_nt (TYPEID_EXPR, type);
|
||
|
||
/* If the type of the type-id is a reference type, the result of the
|
||
typeid expression refers to a type_info object representing the
|
||
referenced type. */
|
||
if (TREE_CODE (type) == REFERENCE_TYPE)
|
||
type = TREE_TYPE (type);
|
||
|
||
/* The top-level cv-qualifiers of the lvalue expression or the type-id
|
||
that is the operand of typeid are always ignored. */
|
||
type = TYPE_MAIN_VARIANT (type);
|
||
|
||
return get_typeid_1 (type);
|
||
}
|
||
|
||
/* Check whether TEST is null before returning RESULT. If TEST is used in
|
||
RESULT, it must have previously had a save_expr applied to it. */
|
||
|
||
static tree
|
||
ifnonnull (test, result)
|
||
tree test, result;
|
||
{
|
||
return build (COND_EXPR, TREE_TYPE (result),
|
||
build (EQ_EXPR, boolean_type_node, test, integer_zero_node),
|
||
cp_convert (TREE_TYPE (result), integer_zero_node),
|
||
result);
|
||
}
|
||
|
||
/* Execute a dynamic cast, as described in section 5.2.6 of the 9/93 working
|
||
paper. */
|
||
|
||
static tree
|
||
build_dynamic_cast_1 (type, expr)
|
||
tree type, expr;
|
||
{
|
||
enum tree_code tc = TREE_CODE (type);
|
||
tree exprtype = TREE_TYPE (expr);
|
||
enum tree_code ec;
|
||
tree dcast_fn;
|
||
|
||
assert (exprtype != NULL_TREE);
|
||
ec = TREE_CODE (exprtype);
|
||
|
||
switch (tc)
|
||
{
|
||
case POINTER_TYPE:
|
||
if (ec == REFERENCE_TYPE)
|
||
{
|
||
expr = convert_from_reference (expr);
|
||
exprtype = TREE_TYPE (expr);
|
||
ec = TREE_CODE (exprtype);
|
||
}
|
||
if (ec != POINTER_TYPE)
|
||
goto fail;
|
||
if (TREE_CODE (TREE_TYPE (exprtype)) != RECORD_TYPE)
|
||
goto fail;
|
||
if (TYPE_SIZE (complete_type (TREE_TYPE (exprtype))) == NULL_TREE)
|
||
goto fail;
|
||
if (TREE_READONLY (TREE_TYPE (exprtype))
|
||
&& ! TYPE_READONLY (TREE_TYPE (type)))
|
||
goto fail;
|
||
if (TYPE_MAIN_VARIANT (TREE_TYPE (type)) == void_type_node)
|
||
break;
|
||
/* else fall through */
|
||
case REFERENCE_TYPE:
|
||
if (TREE_CODE (TREE_TYPE (type)) != RECORD_TYPE)
|
||
goto fail;
|
||
if (TYPE_SIZE (complete_type (TREE_TYPE (type))) == NULL_TREE)
|
||
goto fail;
|
||
break;
|
||
/* else fall through */
|
||
default:
|
||
goto fail;
|
||
}
|
||
|
||
/* Apply trivial conversion T -> T& for dereferenced ptrs. */
|
||
if (ec == RECORD_TYPE)
|
||
{
|
||
exprtype = build_type_variant (exprtype, TREE_READONLY (expr),
|
||
TREE_THIS_VOLATILE (expr));
|
||
exprtype = build_reference_type (exprtype);
|
||
expr = convert_to_reference (exprtype, expr, CONV_IMPLICIT,
|
||
LOOKUP_NORMAL, NULL_TREE);
|
||
ec = REFERENCE_TYPE;
|
||
}
|
||
|
||
if (tc == REFERENCE_TYPE)
|
||
{
|
||
if (ec != REFERENCE_TYPE)
|
||
goto fail;
|
||
if (TREE_CODE (TREE_TYPE (exprtype)) != RECORD_TYPE)
|
||
goto fail;
|
||
if (TYPE_SIZE (complete_type (TREE_TYPE (exprtype))) == NULL_TREE)
|
||
goto fail;
|
||
if (TREE_READONLY (TREE_TYPE (exprtype))
|
||
&& ! TYPE_READONLY (TREE_TYPE (type)))
|
||
goto fail;
|
||
}
|
||
|
||
/* If *type is an unambiguous accessible base class of *exprtype,
|
||
convert statically. */
|
||
{
|
||
int distance;
|
||
tree path;
|
||
|
||
distance = get_base_distance (TREE_TYPE (type), TREE_TYPE (exprtype), 1,
|
||
&path);
|
||
if (distance >= 0)
|
||
return build_vbase_path (PLUS_EXPR, type, expr, path, 0);
|
||
}
|
||
|
||
/* Otherwise *exprtype must be a polymorphic class (have a vtbl). */
|
||
if (TYPE_VIRTUAL_P (TREE_TYPE (exprtype)))
|
||
{
|
||
tree expr1;
|
||
/* if TYPE is `void *', return pointer to complete object. */
|
||
if (tc == POINTER_TYPE
|
||
&& TYPE_MAIN_VARIANT (TREE_TYPE (type)) == void_type_node)
|
||
{
|
||
/* if b is an object, dynamic_cast<void *>(&b) == (void *)&b. */
|
||
if (TREE_CODE (expr) == ADDR_EXPR
|
||
&& TREE_CODE (TREE_OPERAND (expr, 0)) == VAR_DECL
|
||
&& TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == RECORD_TYPE)
|
||
return build1 (NOP_EXPR, type, expr);
|
||
|
||
/* Since expr is used twice below, save it. */
|
||
expr = save_expr (expr);
|
||
|
||
expr1 = build_headof (expr);
|
||
if (TREE_TYPE (expr1) != type)
|
||
expr1 = build1 (NOP_EXPR, type, expr1);
|
||
return ifnonnull (expr, expr1);
|
||
}
|
||
else
|
||
{
|
||
tree retval;
|
||
tree result, td1, td2, td3, elems, expr2;
|
||
|
||
/* If we got here, we can't convert statically. Therefore,
|
||
dynamic_cast<D&>(b) (b an object) cannot succeed. */
|
||
if (ec == REFERENCE_TYPE)
|
||
{
|
||
if (TREE_CODE (expr) == VAR_DECL
|
||
&& TREE_CODE (TREE_TYPE (expr)) == RECORD_TYPE)
|
||
{
|
||
cp_warning ("dynamic_cast of `%#D' to `%#T' can never succeed",
|
||
expr, type);
|
||
return throw_bad_cast ();
|
||
}
|
||
}
|
||
/* Ditto for dynamic_cast<D*>(&b). */
|
||
else if (TREE_CODE (expr) == ADDR_EXPR)
|
||
{
|
||
tree op = TREE_OPERAND (expr, 0);
|
||
if (TREE_CODE (op) == VAR_DECL
|
||
&& TREE_CODE (TREE_TYPE (op)) == RECORD_TYPE)
|
||
{
|
||
cp_warning ("dynamic_cast of `%#D' to `%#T' can never succeed",
|
||
expr, type);
|
||
retval = build_int_2 (0, 0);
|
||
TREE_TYPE (retval) = type;
|
||
return retval;
|
||
}
|
||
}
|
||
|
||
/* Since expr is used twice below, save it. */
|
||
expr = save_expr (expr);
|
||
|
||
expr1 = expr;
|
||
if (tc == REFERENCE_TYPE)
|
||
expr1 = build_unary_op (ADDR_EXPR, expr1, 0);
|
||
|
||
/* Build run-time conversion. */
|
||
expr2 = build_headof (expr1);
|
||
|
||
if (ec == POINTER_TYPE)
|
||
td1 = get_tinfo_fn_dynamic (build_indirect_ref (expr, NULL_PTR));
|
||
else
|
||
td1 = get_tinfo_fn_dynamic (expr);
|
||
td1 = decay_conversion (td1);
|
||
|
||
td2 = decay_conversion
|
||
(get_tinfo_fn (TYPE_MAIN_VARIANT (TREE_TYPE (type))));
|
||
td3 = decay_conversion
|
||
(get_tinfo_fn (TYPE_MAIN_VARIANT (TREE_TYPE (exprtype))));
|
||
|
||
elems = tree_cons
|
||
(NULL_TREE, td1, tree_cons
|
||
(NULL_TREE, td2, tree_cons
|
||
(NULL_TREE, build_int_2 (1, 0), tree_cons
|
||
(NULL_TREE, expr2, tree_cons
|
||
(NULL_TREE, td3, tree_cons
|
||
(NULL_TREE, expr1, NULL_TREE))))));
|
||
|
||
dcast_fn = get_identifier ("__dynamic_cast");
|
||
if (IDENTIFIER_GLOBAL_VALUE (dcast_fn))
|
||
dcast_fn = IDENTIFIER_GLOBAL_VALUE (dcast_fn);
|
||
else
|
||
{
|
||
tree tmp;
|
||
|
||
push_obstacks (&permanent_obstack, &permanent_obstack);
|
||
tmp = tree_cons
|
||
(NULL_TREE, TREE_TYPE (td1), tree_cons
|
||
(NULL_TREE, TREE_TYPE (td1), tree_cons
|
||
(NULL_TREE, integer_type_node, tree_cons
|
||
(NULL_TREE, ptr_type_node, tree_cons
|
||
(NULL_TREE, TREE_TYPE (td1), tree_cons
|
||
(NULL_TREE, ptr_type_node, void_list_node))))));
|
||
tmp = build_function_type (ptr_type_node, tmp);
|
||
dcast_fn = build_lang_decl (FUNCTION_DECL, dcast_fn, tmp);
|
||
DECL_EXTERNAL (dcast_fn) = 1;
|
||
TREE_PUBLIC (dcast_fn) = 1;
|
||
DECL_ARTIFICIAL (dcast_fn) = 1;
|
||
pushdecl_top_level (dcast_fn);
|
||
make_function_rtl (dcast_fn);
|
||
assemble_external (dcast_fn);
|
||
pop_obstacks ();
|
||
}
|
||
|
||
result = build_call
|
||
(dcast_fn, TREE_TYPE (TREE_TYPE (dcast_fn)), elems);
|
||
|
||
if (tc == REFERENCE_TYPE)
|
||
{
|
||
expr1 = throw_bad_cast ();
|
||
expr1 = build_compound_expr
|
||
(expr_tree_cons (NULL_TREE, expr1,
|
||
build_expr_list (NULL_TREE, cp_convert (type, integer_zero_node))));
|
||
TREE_TYPE (expr1) = type;
|
||
result = save_expr (result);
|
||
return build (COND_EXPR, type, result, result, expr1);
|
||
}
|
||
|
||
/* Now back to the type we want from a void*. */
|
||
result = cp_convert (type, result);
|
||
return ifnonnull (expr, result);
|
||
}
|
||
}
|
||
|
||
fail:
|
||
cp_error ("cannot dynamic_cast `%E' (of type `%#T') to type `%#T'",
|
||
expr, exprtype, type);
|
||
return error_mark_node;
|
||
}
|
||
|
||
tree
|
||
build_dynamic_cast (type, expr)
|
||
tree type, expr;
|
||
{
|
||
if (type == error_mark_node || expr == error_mark_node)
|
||
return error_mark_node;
|
||
|
||
if (processing_template_decl)
|
||
return build_min (DYNAMIC_CAST_EXPR, copy_to_permanent (type), expr);
|
||
|
||
return convert_from_reference (build_dynamic_cast_1 (type, expr));
|
||
}
|
||
|
||
/* Build and initialize various sorts of descriptors. Every descriptor
|
||
node has a name associated with it (the name created by mangling).
|
||
For this reason, we use the identifier as our access to the __*_desc
|
||
nodes, instead of sticking them directly in the types. Otherwise we
|
||
would burden all built-in types (and pointer types) with slots that
|
||
we don't necessarily want to use.
|
||
|
||
For each descriptor we build, we build a variable that contains
|
||
the descriptor's information. When we need this info at runtime,
|
||
all we need is access to these variables.
|
||
|
||
Note: these constructors always return the address of the descriptor
|
||
info, since that is simplest for their mutual interaction. */
|
||
|
||
extern tree const_string_type_node;
|
||
|
||
/* Build an initializer for a __si_type_info node. */
|
||
|
||
static void
|
||
expand_si_desc (tdecl, type)
|
||
tree tdecl;
|
||
tree type;
|
||
{
|
||
tree t, elems, fn;
|
||
char *name = build_overload_name (type, 1, 1);
|
||
tree name_string = combine_strings (build_string (strlen (name)+1, name));
|
||
|
||
type = BINFO_TYPE (TREE_VEC_ELT (TYPE_BINFO_BASETYPES (type), 0));
|
||
expand_expr_stmt (get_typeid_1 (type));
|
||
t = decay_conversion (get_tinfo_var (type));
|
||
elems = tree_cons
|
||
(NULL_TREE, decay_conversion (tdecl), tree_cons
|
||
(NULL_TREE, decay_conversion (name_string), tree_cons
|
||
(NULL_TREE, t, NULL_TREE)));
|
||
|
||
fn = get_identifier ("__rtti_si");
|
||
if (IDENTIFIER_GLOBAL_VALUE (fn))
|
||
fn = IDENTIFIER_GLOBAL_VALUE (fn);
|
||
else
|
||
{
|
||
tree tmp;
|
||
push_obstacks (&permanent_obstack, &permanent_obstack);
|
||
tmp = tree_cons
|
||
(NULL_TREE, ptr_type_node, tree_cons
|
||
(NULL_TREE, const_string_type_node, tree_cons
|
||
(NULL_TREE, build_pointer_type (type_info_type_node),
|
||
void_list_node)));
|
||
tmp = build_function_type (void_type_node, tmp);
|
||
|
||
fn = build_lang_decl (FUNCTION_DECL, fn, tmp);
|
||
DECL_EXTERNAL (fn) = 1;
|
||
TREE_PUBLIC (fn) = 1;
|
||
DECL_ARTIFICIAL (fn) = 1;
|
||
pushdecl_top_level (fn);
|
||
make_function_rtl (fn);
|
||
assemble_external (fn);
|
||
pop_obstacks ();
|
||
}
|
||
|
||
fn = build_call (fn, TREE_TYPE (TREE_TYPE (fn)), elems);
|
||
expand_expr_stmt (fn);
|
||
}
|
||
|
||
/* Build an initializer for a __class_type_info node. */
|
||
|
||
static void
|
||
expand_class_desc (tdecl, type)
|
||
tree tdecl;
|
||
tree type;
|
||
{
|
||
tree name_string;
|
||
tree fn, tmp;
|
||
char *name;
|
||
|
||
int i = CLASSTYPE_N_BASECLASSES (type);
|
||
int base_cnt = 0;
|
||
tree binfos = TYPE_BINFO_BASETYPES (type);
|
||
#if 0
|
||
/* See code below that used these. */
|
||
tree vb = CLASSTYPE_VBASECLASSES (type);
|
||
int n_base = i;
|
||
#endif
|
||
tree base, elems, access, offset, isvir;
|
||
tree elt, elts = NULL_TREE;
|
||
static tree base_info_type_node;
|
||
|
||
if (base_info_type_node == NULL_TREE)
|
||
{
|
||
tree fields [4];
|
||
|
||
/* A reasonably close approximation of __class_type_info::base_info */
|
||
|
||
push_obstacks (&permanent_obstack, &permanent_obstack);
|
||
base_info_type_node = make_lang_type (RECORD_TYPE);
|
||
|
||
/* Actually const __user_type_info * */
|
||
fields [0] = build_lang_field_decl
|
||
(FIELD_DECL, NULL_TREE,
|
||
build_pointer_type (build_type_variant (type_info_type_node, 1, 0)));
|
||
fields [1] = build_lang_field_decl
|
||
(FIELD_DECL, NULL_TREE, unsigned_intSI_type_node);
|
||
DECL_BIT_FIELD (fields[1]) = 1;
|
||
DECL_FIELD_SIZE (fields[1]) = 29;
|
||
|
||
fields [2] = build_lang_field_decl
|
||
(FIELD_DECL, NULL_TREE, boolean_type_node);
|
||
DECL_BIT_FIELD (fields[2]) = 1;
|
||
DECL_FIELD_SIZE (fields[2]) = 1;
|
||
|
||
/* Actually enum access */
|
||
fields [3] = build_lang_field_decl
|
||
(FIELD_DECL, NULL_TREE, integer_type_node);
|
||
DECL_BIT_FIELD (fields[3]) = 1;
|
||
DECL_FIELD_SIZE (fields[3]) = 2;
|
||
|
||
finish_builtin_type (base_info_type_node, "__base_info", fields,
|
||
3, ptr_type_node);
|
||
pop_obstacks ();
|
||
}
|
||
|
||
while (--i >= 0)
|
||
{
|
||
tree binfo = TREE_VEC_ELT (binfos, i);
|
||
|
||
expand_expr_stmt (get_typeid_1 (BINFO_TYPE (binfo)));
|
||
base = decay_conversion (get_tinfo_var (BINFO_TYPE (binfo)));
|
||
|
||
if (TREE_VIA_VIRTUAL (binfo))
|
||
{
|
||
tree t = BINFO_TYPE (binfo);
|
||
char *name;
|
||
tree field;
|
||
|
||
name = (char *) alloca (TYPE_NAME_LENGTH (t)+sizeof (VBASE_NAME)+1);
|
||
sprintf (name, VBASE_NAME_FORMAT, TYPE_NAME_STRING (t));
|
||
field = lookup_field (type, get_identifier (name), 0, 0);
|
||
offset = size_binop (FLOOR_DIV_EXPR,
|
||
DECL_FIELD_BITPOS (field), size_int (BITS_PER_UNIT));
|
||
offset = convert (sizetype, offset);
|
||
}
|
||
else
|
||
offset = BINFO_OFFSET (binfo);
|
||
|
||
if (TREE_VIA_PUBLIC (binfo))
|
||
access = access_public_node;
|
||
else if (TREE_VIA_PROTECTED (binfo))
|
||
access = access_protected_node;
|
||
else
|
||
access = access_private_node;
|
||
if (TREE_VIA_VIRTUAL (binfo))
|
||
isvir = boolean_true_node;
|
||
else
|
||
isvir = boolean_false_node;
|
||
|
||
elt = build
|
||
(CONSTRUCTOR, base_info_type_node, NULL_TREE, tree_cons
|
||
(NULL_TREE, base, tree_cons
|
||
(NULL_TREE, offset, tree_cons
|
||
(NULL_TREE, isvir, tree_cons
|
||
(NULL_TREE, access, NULL_TREE)))));
|
||
TREE_HAS_CONSTRUCTOR (elt) = TREE_CONSTANT (elt) = TREE_STATIC (elt) = 1;
|
||
elts = expr_tree_cons (NULL_TREE, elt, elts);
|
||
base_cnt++;
|
||
}
|
||
#if 0
|
||
i = n_base;
|
||
while (vb)
|
||
{
|
||
tree b;
|
||
access = access_public_node;
|
||
while (--i >= 0)
|
||
{
|
||
b = TREE_VEC_ELT (binfos, i);
|
||
if (BINFO_TYPE (vb) == BINFO_TYPE (b) && TREE_VIA_VIRTUAL (b))
|
||
{
|
||
if (TREE_VIA_PUBLIC (b))
|
||
access = access_public_node;
|
||
else if (TREE_VIA_PROTECTED (b))
|
||
access = access_protected_node;
|
||
else
|
||
access = access_private_node;
|
||
break;
|
||
}
|
||
}
|
||
base = build_t_desc (BINFO_TYPE (vb), 1);
|
||
offset = BINFO_OFFSET (vb);
|
||
isvir = build_int_2 (1, 0);
|
||
|
||
base_list = expr_tree_cons (NULL_TREE, base, base_list);
|
||
isvir_list = expr_tree_cons (NULL_TREE, isvir, isvir_list);
|
||
acc_list = expr_tree_cons (NULL_TREE, access, acc_list);
|
||
off_list = expr_tree_cons (NULL_TREE, offset, off_list);
|
||
|
||
base_cnt++;
|
||
vb = TREE_CHAIN (vb);
|
||
}
|
||
#endif
|
||
|
||
name = build_overload_name (type, 1, 1);
|
||
name_string = combine_strings (build_string (strlen (name)+1, name));
|
||
|
||
{
|
||
tree arrtype = build_array_type (base_info_type_node, NULL_TREE);
|
||
elts = build (CONSTRUCTOR, arrtype, NULL_TREE, elts);
|
||
TREE_HAS_CONSTRUCTOR (elts) = TREE_CONSTANT (elts)
|
||
= TREE_STATIC (elts) = 1;
|
||
complete_array_type (arrtype, elts, 1);
|
||
}
|
||
|
||
elems = tree_cons
|
||
(NULL_TREE, decay_conversion (tdecl), tree_cons
|
||
(NULL_TREE, decay_conversion (name_string), tree_cons
|
||
(NULL_TREE, decay_conversion (elts), tree_cons
|
||
(NULL_TREE, cp_convert (sizetype, build_int_2 (base_cnt, 0)),
|
||
NULL_TREE))));
|
||
|
||
fn = get_identifier ("__rtti_class");
|
||
if (IDENTIFIER_GLOBAL_VALUE (fn))
|
||
fn = IDENTIFIER_GLOBAL_VALUE (fn);
|
||
else
|
||
{
|
||
push_obstacks (&permanent_obstack, &permanent_obstack);
|
||
tmp = tree_cons
|
||
(NULL_TREE, ptr_type_node, tree_cons
|
||
(NULL_TREE, const_string_type_node, tree_cons
|
||
(NULL_TREE, build_pointer_type (base_info_type_node), tree_cons
|
||
(NULL_TREE, sizetype, void_list_node))));
|
||
tmp = build_function_type (void_type_node, tmp);
|
||
|
||
fn = build_lang_decl (FUNCTION_DECL, fn, tmp);
|
||
DECL_EXTERNAL (fn) = 1;
|
||
TREE_PUBLIC (fn) = 1;
|
||
DECL_ARTIFICIAL (fn) = 1;
|
||
pushdecl_top_level (fn);
|
||
make_function_rtl (fn);
|
||
assemble_external (fn);
|
||
pop_obstacks ();
|
||
}
|
||
|
||
fn = build_call (fn, TREE_TYPE (TREE_TYPE (fn)), elems);
|
||
expand_expr_stmt (fn);
|
||
}
|
||
|
||
/* Build an initializer for a __pointer_type_info node. */
|
||
|
||
static void
|
||
expand_ptr_desc (tdecl, type)
|
||
tree tdecl;
|
||
tree type;
|
||
{
|
||
tree t, elems, fn;
|
||
char *name = build_overload_name (type, 1, 1);
|
||
tree name_string = combine_strings (build_string (strlen (name)+1, name));
|
||
|
||
type = TREE_TYPE (type);
|
||
expand_expr_stmt (get_typeid_1 (type));
|
||
t = decay_conversion (get_tinfo_var (type));
|
||
elems = tree_cons
|
||
(NULL_TREE, decay_conversion (tdecl), tree_cons
|
||
(NULL_TREE, decay_conversion (name_string), tree_cons
|
||
(NULL_TREE, t, NULL_TREE)));
|
||
|
||
fn = get_identifier ("__rtti_ptr");
|
||
if (IDENTIFIER_GLOBAL_VALUE (fn))
|
||
fn = IDENTIFIER_GLOBAL_VALUE (fn);
|
||
else
|
||
{
|
||
tree tmp;
|
||
push_obstacks (&permanent_obstack, &permanent_obstack);
|
||
tmp = tree_cons
|
||
(NULL_TREE, ptr_type_node, tree_cons
|
||
(NULL_TREE, const_string_type_node, tree_cons
|
||
(NULL_TREE, build_pointer_type (type_info_type_node),
|
||
void_list_node)));
|
||
tmp = build_function_type (void_type_node, tmp);
|
||
|
||
fn = build_lang_decl (FUNCTION_DECL, fn, tmp);
|
||
DECL_EXTERNAL (fn) = 1;
|
||
TREE_PUBLIC (fn) = 1;
|
||
DECL_ARTIFICIAL (fn) = 1;
|
||
pushdecl_top_level (fn);
|
||
make_function_rtl (fn);
|
||
assemble_external (fn);
|
||
pop_obstacks ();
|
||
}
|
||
|
||
fn = build_call (fn, TREE_TYPE (TREE_TYPE (fn)), elems);
|
||
expand_expr_stmt (fn);
|
||
}
|
||
|
||
/* Build an initializer for a __attr_type_info node. */
|
||
|
||
static void
|
||
expand_attr_desc (tdecl, type)
|
||
tree tdecl;
|
||
tree type;
|
||
{
|
||
tree elems, t, fn;
|
||
char *name = build_overload_name (type, 1, 1);
|
||
tree name_string = combine_strings (build_string (strlen (name)+1, name));
|
||
tree attrval = build_int_2
|
||
(TYPE_READONLY (type) | TYPE_VOLATILE (type) * 2, 0);
|
||
|
||
expand_expr_stmt (get_typeid_1 (TYPE_MAIN_VARIANT (type)));
|
||
t = decay_conversion (get_tinfo_var (TYPE_MAIN_VARIANT (type)));
|
||
elems = tree_cons
|
||
(NULL_TREE, decay_conversion (tdecl), tree_cons
|
||
(NULL_TREE, decay_conversion (name_string), tree_cons
|
||
(NULL_TREE, attrval, expr_tree_cons (NULL_TREE, t, NULL_TREE))));
|
||
|
||
fn = get_identifier ("__rtti_attr");
|
||
if (IDENTIFIER_GLOBAL_VALUE (fn))
|
||
fn = IDENTIFIER_GLOBAL_VALUE (fn);
|
||
else
|
||
{
|
||
tree tmp;
|
||
push_obstacks (&permanent_obstack, &permanent_obstack);
|
||
tmp = tree_cons
|
||
(NULL_TREE, ptr_type_node, tree_cons
|
||
(NULL_TREE, const_string_type_node, tree_cons
|
||
(NULL_TREE, integer_type_node, tree_cons
|
||
(NULL_TREE, build_pointer_type (type_info_type_node),
|
||
void_list_node))));
|
||
tmp = build_function_type (void_type_node, tmp);
|
||
|
||
fn = build_lang_decl (FUNCTION_DECL, fn, tmp);
|
||
DECL_EXTERNAL (fn) = 1;
|
||
TREE_PUBLIC (fn) = 1;
|
||
DECL_ARTIFICIAL (fn) = 1;
|
||
pushdecl_top_level (fn);
|
||
make_function_rtl (fn);
|
||
assemble_external (fn);
|
||
pop_obstacks ();
|
||
}
|
||
|
||
fn = build_call (fn, TREE_TYPE (TREE_TYPE (fn)), elems);
|
||
expand_expr_stmt (fn);
|
||
}
|
||
|
||
/* Build an initializer for a type_info node that just has a name. */
|
||
|
||
static void
|
||
expand_generic_desc (tdecl, type, fnname)
|
||
tree tdecl;
|
||
tree type;
|
||
char *fnname;
|
||
{
|
||
char *name = build_overload_name (type, 1, 1);
|
||
tree name_string = combine_strings (build_string (strlen (name)+1, name));
|
||
tree elems = tree_cons
|
||
(NULL_TREE, decay_conversion (tdecl), tree_cons
|
||
(NULL_TREE, decay_conversion (name_string), NULL_TREE));
|
||
|
||
tree fn = get_identifier (fnname);
|
||
if (IDENTIFIER_GLOBAL_VALUE (fn))
|
||
fn = IDENTIFIER_GLOBAL_VALUE (fn);
|
||
else
|
||
{
|
||
tree tmp;
|
||
push_obstacks (&permanent_obstack, &permanent_obstack);
|
||
tmp = tree_cons
|
||
(NULL_TREE, ptr_type_node, tree_cons
|
||
(NULL_TREE, const_string_type_node, void_list_node));
|
||
tmp = build_function_type (void_type_node, tmp);
|
||
|
||
fn = build_lang_decl (FUNCTION_DECL, fn, tmp);
|
||
DECL_EXTERNAL (fn) = 1;
|
||
TREE_PUBLIC (fn) = 1;
|
||
DECL_ARTIFICIAL (fn) = 1;
|
||
pushdecl_top_level (fn);
|
||
make_function_rtl (fn);
|
||
assemble_external (fn);
|
||
pop_obstacks ();
|
||
}
|
||
|
||
fn = build_call (fn, TREE_TYPE (TREE_TYPE (fn)), elems);
|
||
expand_expr_stmt (fn);
|
||
}
|
||
|
||
/* Generate the code for a type_info initialization function.
|
||
Note that we take advantage of the passage
|
||
|
||
5.2.7 Type identification [expr.typeid]
|
||
|
||
Whether or not the destructor is called for the type_info object at the
|
||
end of the program is unspecified.
|
||
|
||
and don't bother to arrange for these objects to be destroyed. It
|
||
doesn't matter, anyway, since the destructors don't do anything.
|
||
|
||
This must only be called from toplevel (i.e. from finish_file)! */
|
||
|
||
void
|
||
synthesize_tinfo_fn (fndecl)
|
||
tree fndecl;
|
||
{
|
||
tree type = TREE_TYPE (DECL_NAME (fndecl));
|
||
tree tmp, addr, tdecl;
|
||
|
||
if (at_eof)
|
||
{
|
||
import_export_decl (fndecl);
|
||
if (DECL_REALLY_EXTERN (fndecl))
|
||
return;
|
||
}
|
||
|
||
tdecl = get_tinfo_var (type);
|
||
DECL_EXTERNAL (tdecl) = 0;
|
||
TREE_STATIC (tdecl) = 1;
|
||
DECL_COMMON (tdecl) = 1;
|
||
TREE_USED (tdecl) = 1;
|
||
DECL_ALIGN (tdecl) = TYPE_ALIGN (ptr_type_node);
|
||
cp_finish_decl (tdecl, NULL_TREE, NULL_TREE, 0, 0);
|
||
|
||
start_function (NULL_TREE, fndecl, NULL_TREE, 1);
|
||
store_parm_decls ();
|
||
clear_last_expr ();
|
||
push_momentary ();
|
||
|
||
/* If the first word of the array (the vtable) is non-zero, we've already
|
||
initialized the object, so don't do it again. */
|
||
addr = decay_conversion (tdecl);
|
||
tmp = cp_convert (build_pointer_type (ptr_type_node), addr);
|
||
tmp = build_indirect_ref (tmp, 0);
|
||
tmp = build_binary_op (EQ_EXPR, tmp, integer_zero_node, 1);
|
||
expand_start_cond (tmp, 0);
|
||
|
||
if (TREE_CODE (type) == FUNCTION_TYPE)
|
||
expand_generic_desc (tdecl, type, "__rtti_func");
|
||
else if (TREE_CODE (type) == ARRAY_TYPE)
|
||
expand_generic_desc (tdecl, type, "__rtti_array");
|
||
else if (TYPE_VOLATILE (type) || TYPE_READONLY (type))
|
||
expand_attr_desc (tdecl, type);
|
||
else if (TREE_CODE (type) == POINTER_TYPE)
|
||
{
|
||
if (TREE_CODE (TREE_TYPE (type)) == OFFSET_TYPE)
|
||
expand_generic_desc (tdecl, type, "__rtti_ptmd");
|
||
else if (TREE_CODE (TREE_TYPE (type)) == METHOD_TYPE)
|
||
expand_generic_desc (tdecl, type, "__rtti_ptmf");
|
||
else
|
||
expand_ptr_desc (tdecl, type);
|
||
}
|
||
else if (TYPE_PTRMEMFUNC_P (type))
|
||
expand_generic_desc (tdecl, type, "__rtti_ptmf");
|
||
else if (IS_AGGR_TYPE (type))
|
||
{
|
||
if (CLASSTYPE_N_BASECLASSES (type) == 0)
|
||
expand_generic_desc (tdecl, type, "__rtti_user");
|
||
else if (! TYPE_USES_COMPLEX_INHERITANCE (type)
|
||
&& (TREE_VIA_PUBLIC
|
||
(TREE_VEC_ELT (TYPE_BINFO_BASETYPES (type), 0))))
|
||
expand_si_desc (tdecl, type);
|
||
else
|
||
expand_class_desc (tdecl, type);
|
||
}
|
||
else if (TREE_CODE (type) == ENUMERAL_TYPE)
|
||
expand_generic_desc (tdecl, type, "__rtti_user");
|
||
else
|
||
my_friendly_abort (252);
|
||
|
||
expand_end_cond ();
|
||
|
||
/* OK, now return the type_info object. */
|
||
tmp = cp_convert (build_pointer_type (type_info_type_node), addr);
|
||
tmp = build_indirect_ref (tmp, 0);
|
||
c_expand_return (tmp);
|
||
finish_function (lineno, 0, 0);
|
||
}
|