gcc/gcc/cp/rtti.c

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/* RunTime Type Identification
Copyright (C) 1995, 96-97, 1998, 1999, 2000 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. */
#include "config.h"
#include "system.h"
#include "tree.h"
#include "cp-tree.h"
#include "flags.h"
#include "output.h"
#include "assert.h"
#include "toplev.h"
#ifndef INT_TYPE_SIZE
#define INT_TYPE_SIZE BITS_PER_WORD
#endif
extern struct obstack permanent_obstack;
static tree build_runtime_decl PARAMS ((const char *, tree));
static tree build_headof_sub PARAMS ((tree));
static tree build_headof PARAMS ((tree));
static tree get_tinfo_var PARAMS ((tree));
static tree ifnonnull PARAMS ((tree, tree));
static tree tinfo_name PARAMS ((tree));
static tree get_base_offset PARAMS ((tree, tree));
static tree build_dynamic_cast_1 PARAMS ((tree, tree));
static void expand_si_desc PARAMS ((tree, tree));
static void expand_class_desc PARAMS ((tree, tree));
static void expand_attr_desc PARAMS ((tree, tree));
static void expand_ptr_desc PARAMS ((tree, tree));
static void expand_generic_desc PARAMS ((tree, tree, const char *));
static tree throw_bad_cast PARAMS ((void));
static tree throw_bad_typeid PARAMS ((void));
static tree get_tinfo_decl_dynamic PARAMS ((tree));
static tree tinfo_from_decl PARAMS ((tree));
void
init_rtti_processing ()
{
if (flag_honor_std)
push_namespace (get_identifier ("std"));
type_info_type_node = xref_tag
(class_type_node, get_identifier ("type_info"), 1);
if (flag_honor_std)
pop_namespace ();
tinfo_decl_id = get_identifier ("__tf");
tinfo_decl_type = build_function_type
(build_reference_type
(build_qualified_type
(type_info_type_node, TYPE_QUAL_CONST)),
void_list_node);
tinfo_var_id = get_identifier ("__ti");
}
/* Given a pointer to an object with at least one virtual table
pointer somewhere, return a pointer to a possible sub-object that
has a virtual table pointer in it that is the vtable parent for
that sub-object. */
static tree
build_headof_sub (exp)
tree exp;
{
tree type = TREE_TYPE (TREE_TYPE (exp));
tree basetype = CLASSTYPE_RTTI (type);
tree binfo = get_binfo (basetype, type, 0);
exp = convert_pointer_to_real (binfo, exp);
return exp;
}
/* Given the expression EXP of type `class *', return the head of the
object pointed to by EXP with type cv void*, if the class has any
virtual functions (TYPE_POLYMORPHIC_P), else just return the
expression. */
static tree
build_headof (exp)
tree exp;
{
tree type = TREE_TYPE (exp);
tree aref;
tree offset;
my_friendly_assert (TREE_CODE (type) == POINTER_TYPE, 20000112);
type = TREE_TYPE (type);
if (!TYPE_POLYMORPHIC_P (type))
return exp;
if (CLASSTYPE_COM_INTERFACE (type))
{
cp_error ("RTTI not supported for COM interface type `%T'", type);
return error_mark_node;
}
/* If we don't have rtti stuff, get to a sub-object that does. */
if (!CLASSTYPE_VFIELDS (TREE_TYPE (TREE_TYPE (exp))))
exp = build_headof_sub (exp);
/* We use this a couple of times below, protect it. */
exp = save_expr (exp);
aref = build_vtbl_ref (build_indirect_ref (exp, NULL_PTR), integer_zero_node);
if (flag_vtable_thunks)
offset = aref;
else
offset = build_component_ref (aref, delta_identifier, NULL_TREE, 0);
type = build_qualified_type (ptr_type_node,
CP_TYPE_QUALS (TREE_TYPE (exp)));
return build (PLUS_EXPR, type, exp,
cp_convert (ptrdiff_type_node, offset));
}
/* Build a decl to a runtime entry point taking void and returning TYPE.
Although the entry point may never return, making its return type
consistent is necessary. */
static tree
build_runtime_decl (name, type)
const char *name;
tree type;
{
tree d = get_identifier (name);
if (IDENTIFIER_GLOBAL_VALUE (d))
d = IDENTIFIER_GLOBAL_VALUE (d);
else
{
type = build_function_type (type, void_list_node);
d = build_lang_decl (FUNCTION_DECL, d, type);
DECL_EXTERNAL (d) = 1;
TREE_PUBLIC (d) = 1;
DECL_ARTIFICIAL (d) = 1;
pushdecl_top_level (d);
make_function_rtl (d);
}
mark_used (d);
return d;
}
/* Get a bad_cast node for the program to throw...
See libstdc++/exception.cc for __throw_bad_cast */
static tree
throw_bad_cast ()
{
if (!throw_bad_cast_node)
throw_bad_cast_node = build_runtime_decl
("__throw_bad_cast", ptr_type_node);
return build_call (throw_bad_cast_node,
TREE_TYPE (TREE_TYPE (throw_bad_cast_node)),
NULL_TREE);
}
static tree
throw_bad_typeid ()
{
if (!throw_bad_typeid_node)
throw_bad_typeid_node = build_runtime_decl
("__throw_bad_typeid",
build_reference_type
(build_qualified_type
(type_info_type_node, TYPE_QUAL_CONST)));
return build_call (throw_bad_typeid_node,
TREE_TYPE (TREE_TYPE (throw_bad_typeid_node)),
NULL_TREE);
}
/* Return a pointer to type_info function associated with the expression EXP.
If EXP is a reference to a polymorphic class, return the dynamic type;
otherwise return the static type of the expression. */
static tree
get_tinfo_decl_dynamic (exp)
tree exp;
{
tree type;
if (exp == error_mark_node)
return error_mark_node;
type = TREE_TYPE (exp);
/* peel back references, so they match. */
if (TREE_CODE (type) == REFERENCE_TYPE)
type = TREE_TYPE (type);
/* Peel off cv qualifiers. */
type = TYPE_MAIN_VARIANT (type);
if (type != void_type_node)
type = complete_type_or_else (type, exp);
if (!type)
return error_mark_node;
/* If exp is a reference to polymorphic type, get the real type_info. */
if (TYPE_POLYMORPHIC_P (type) && ! resolves_to_fixed_type_p (exp, 0))
{
/* build reference to type_info from vtable. */
tree t;
if (! flag_rtti)
error ("taking dynamic typeid of object with -fno-rtti");
if (CLASSTYPE_COM_INTERFACE (type))
{
cp_error ("RTTI not supported for COM interface type `%T'", type);
return error_mark_node;
}
/* If we don't have rtti stuff, get to a sub-object that does. */
if (! CLASSTYPE_VFIELDS (type))
{
exp = build_unary_op (ADDR_EXPR, exp, 0);
exp = build_headof_sub (exp);
exp = build_indirect_ref (exp, NULL_PTR);
}
if (flag_vtable_thunks)
t = build_vfn_ref ((tree *) 0, exp, integer_one_node);
else
t = build_vfn_ref ((tree *) 0, exp, integer_zero_node);
TREE_TYPE (t) = build_pointer_type (tinfo_decl_type);
return t;
}
/* otherwise return the type_info for the static type of the expr. */
exp = get_tinfo_decl (TYPE_MAIN_VARIANT (type));
return build_unary_op (ADDR_EXPR, exp, 0);
}
tree
build_typeid (exp)
tree exp;
{
tree cond = NULL_TREE;
int nonnull = 0;
if (! flag_rtti)
{
error ("cannot use typeid with -fno-rtti");
return error_mark_node;
}
if (TYPE_SIZE (type_info_type_node) == NULL_TREE)
{
error ("must #include <typeinfo> before using typeid");
return error_mark_node;
}
if (processing_template_decl)
return build_min_nt (TYPEID_EXPR, exp);
if (TREE_CODE (exp) == INDIRECT_REF
&& TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == POINTER_TYPE
&& TYPE_POLYMORPHIC_P (TREE_TYPE (exp))
&& ! resolves_to_fixed_type_p (exp, &nonnull)
&& ! nonnull)
{
exp = stabilize_reference (exp);
cond = cp_convert (boolean_type_node, TREE_OPERAND (exp, 0));
}
exp = get_tinfo_decl_dynamic (exp);
if (exp == error_mark_node)
return error_mark_node;
exp = tinfo_from_decl (exp);
if (cond)
{
tree bad = throw_bad_typeid ();
exp = build (COND_EXPR, TREE_TYPE (exp), cond, exp, bad);
}
return convert_from_reference (exp);
}
static tree
get_tinfo_var (type)
tree type;
{
tree tname = build_overload_with_type (tinfo_var_id, type);
tree 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_QUALS (type) != TYPE_UNQUALIFIED)
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_BASE_CONVS_MAY_REQUIRE_CODE_P (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;
/* 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)));
return declare_global_var (tname, arrtype);
}
/* Generate the NTBS name of a type. */
static tree
tinfo_name (type)
tree type;
{
const char *name = build_overload_name (type, 1, 1);
tree name_string = combine_strings (build_string (strlen (name) + 1, name));
return name_string;
}
/* Returns a decl for a function or variable which can be used to obtain a
type_info object for TYPE. The old-abi uses functions, the new-abi will
use the type_info object directly. You can take the address of the
returned decl, to save the decl. To use the decl call
tinfo_from_decl. You must arrange that the decl is mark_used, if
actually use it --- decls in vtables are only used if the vtable is
output. */
tree
get_tinfo_decl (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_decl_id, type);
if (IDENTIFIER_GLOBAL_VALUE (name))
return IDENTIFIER_GLOBAL_VALUE (name);
d = build_lang_decl (FUNCTION_DECL, name, tinfo_decl_type);
DECL_EXTERNAL (d) = 1;
TREE_PUBLIC (d) = 1;
DECL_ARTIFICIAL (d) = 1;
DECL_NOT_REALLY_EXTERN (d) = 1;
SET_DECL_TINFO_FN_P (d);
TREE_TYPE (name) = type;
pushdecl_top_level (d);
make_function_rtl (d);
mark_inline_for_output (d);
return d;
}
/* Given an expr produced by get_tinfo_decl, return an expr which
produces a reference to the type_info object. */
static tree
tinfo_from_decl (expr)
tree expr;
{
tree t = build_call (expr, TREE_TYPE (tinfo_decl_type), NULL_TREE);
return t;
}
tree
get_typeid_1 (type)
tree type;
{
tree t;
t = get_tinfo_decl (type);
t = tinfo_from_decl (t);
return convert_from_reference (t);
}
/* Return the type_info object for TYPE. */
tree
get_typeid (type)
tree type;
{
if (type == error_mark_node)
return error_mark_node;
if (TYPE_SIZE (type_info_type_node) == NULL_TREE)
{
error ("must #include <typeinfo> before using typeid");
return error_mark_node;
}
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);
if (type != void_type_node)
type = complete_type_or_else (type, NULL_TREE);
if (!type)
return error_mark_node;
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);
}
/* Generate the constant expression describing where direct base BINFO
appears within the PARENT. How to interpret this expression depends on
details of the ABI, which the runtime must be aware of. */
static tree
get_base_offset (binfo, parent)
tree binfo;
tree parent;
{
tree offset;
if (!TREE_VIA_VIRTUAL (binfo))
offset = BINFO_OFFSET (binfo);
else if (!vbase_offsets_in_vtable_p ())
{
tree t = BINFO_TYPE (binfo);
const char *name;
tree field;
FORMAT_VBASE_NAME (name, t);
field = lookup_field (parent, 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
{
/* Under the new ABI, we store the vtable offset at which
the virtual base offset can be found. */
tree vbase = BINFO_FOR_VBASE (BINFO_TYPE (binfo), parent);
offset = convert (sizetype, BINFO_VPTR_FIELD (vbase));
}
return offset;
}
/* 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;
enum tree_code ec;
tree dcast_fn;
tree old_expr = expr;
if (TREE_CODE (expr) == OFFSET_REF)
expr = resolve_offset_ref (expr);
exprtype = TREE_TYPE (expr);
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 (!at_least_as_qualified_p (TREE_TYPE (type),
TREE_TYPE (exprtype)))
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_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 (!at_least_as_qualified_p (TREE_TYPE (type),
TREE_TYPE (exprtype)))
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 == -2)
{
cp_error ("dynamic_cast from `%T' to ambiguous base class `%T'",
TREE_TYPE (exprtype), TREE_TYPE (type));
return error_mark_node;
}
if (distance == -3)
{
cp_error ("dynamic_cast from `%T' to private base class `%T'",
TREE_TYPE (exprtype), TREE_TYPE (type));
return error_mark_node;
}
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_POLYMORPHIC_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;
tree static_type, target_type, boff;
/* If we got here, we can't convert statically. Therefore,
dynamic_cast<D&>(b) (b an object) cannot succeed. */
if (ec == REFERENCE_TYPE)
{
if (TREE_CODE (old_expr) == VAR_DECL
&& TREE_CODE (TREE_TYPE (old_expr)) == RECORD_TYPE)
{
tree expr = throw_bad_cast ();
cp_warning ("dynamic_cast of `%#D' to `%#T' can never succeed",
old_expr, type);
/* Bash it to the expected type. */
TREE_TYPE (expr) = type;
return expr;
}
}
/* Ditto for dynamic_cast<D*>(&b). */
else if (TREE_CODE (expr) == ADDR_EXPR)
{
tree op = TREE_OPERAND (expr, 0);
if (TREE_CODE (op) == VAR_DECL
&& TREE_CODE (TREE_TYPE (op)) == RECORD_TYPE)
{
cp_warning ("dynamic_cast of `%#D' to `%#T' can never succeed",
op, 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_decl_dynamic (build_indirect_ref (expr, NULL_PTR));
else
td1 = get_tinfo_decl_dynamic (expr);
target_type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
static_type = TYPE_MAIN_VARIANT (TREE_TYPE (exprtype));
td2 = build_unary_op (ADDR_EXPR, get_tinfo_decl (target_type), 0);
td3 = build_unary_op (ADDR_EXPR, get_tinfo_decl (static_type), 0);
/* Determine how T and V are related. */
boff = get_dynamic_cast_base_type (static_type, target_type);
elems = tree_cons
(NULL_TREE, td1, tree_cons
(NULL_TREE, td2, tree_cons
(NULL_TREE, boff, tree_cons
(NULL_TREE, expr2, tree_cons
(NULL_TREE, td3, tree_cons
(NULL_TREE, expr1, NULL_TREE))))));
dcast_fn = dynamic_cast_node;
if (!dcast_fn)
{
tree tmp;
tree tinfo_ptr = build_pointer_type (tinfo_decl_type);
tmp = tree_cons
(NULL_TREE, tinfo_ptr, tree_cons
(NULL_TREE, tinfo_ptr, tree_cons
(NULL_TREE, integer_type_node, tree_cons
(NULL_TREE, ptr_type_node, tree_cons
(NULL_TREE, tinfo_ptr, 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,
get_identifier ("__dynamic_cast_2"),
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);
dynamic_cast_node = dcast_fn;
}
mark_used (dcast_fn);
result = build_call
(dcast_fn, TREE_TYPE (TREE_TYPE (dcast_fn)), elems);
if (tc == REFERENCE_TYPE)
{
expr1 = throw_bad_cast ();
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);
}
}
cp_error ("dynamic_cast from non-polymorphic type `%#T'", exprtype);
return error_mark_node;
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, 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. */
/* Build an initializer for a __si_type_info node. */
static void
expand_si_desc (tdecl, type)
tree tdecl;
tree type;
{
tree t, elems, fn;
tree name_string = tinfo_name (type);
type = BINFO_TYPE (TREE_VEC_ELT (TYPE_BINFO_BASETYPES (type), 0));
finish_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;
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);
}
mark_used (fn);
fn = build_call (fn, TREE_TYPE (TREE_TYPE (fn)), elems);
finish_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;
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;
if (base_desc_type_node == NULL_TREE)
{
tree fields [4];
/* A reasonably close approximation of __class_type_info::base_info */
base_desc_type_node = make_aggr_type (RECORD_TYPE);
/* Actually const __user_type_info * */
fields [0] = build_lang_decl
(FIELD_DECL, NULL_TREE,
build_pointer_type (build_qualified_type
(type_info_type_node,
TYPE_QUAL_CONST)));
fields [1] = build_lang_decl
(FIELD_DECL, NULL_TREE,
flag_new_abi ? intSI_type_node : unsigned_intSI_type_node);
DECL_BIT_FIELD (fields[1]) = 1;
DECL_FIELD_SIZE (fields[1]) = 29;
fields [2] = build_lang_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_decl
(FIELD_DECL, NULL_TREE, integer_type_node);
DECL_BIT_FIELD (fields[3]) = 1;
DECL_FIELD_SIZE (fields[3]) = 2;
finish_builtin_type (base_desc_type_node, "__base_info", fields,
3, ptr_type_node);
}
while (--i >= 0)
{
tree binfo = TREE_VEC_ELT (binfos, i);
finish_expr_stmt (get_typeid_1 (BINFO_TYPE (binfo)));
base = decay_conversion (get_tinfo_var (BINFO_TYPE (binfo)));
offset = get_base_offset (binfo, type);
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_desc_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 = 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 = tree_cons (NULL_TREE, base, base_list);
isvir_list = tree_cons (NULL_TREE, isvir, isvir_list);
acc_list = tree_cons (NULL_TREE, access, acc_list);
off_list = tree_cons (NULL_TREE, offset, off_list);
base_cnt++;
vb = TREE_CHAIN (vb);
}
#endif
name_string = tinfo_name (type);
{
tree arrtype = build_array_type (base_desc_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
{
tmp = tree_cons
(NULL_TREE, ptr_type_node, tree_cons
(NULL_TREE, const_string_type_node, tree_cons
(NULL_TREE, build_pointer_type (base_desc_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);
}
mark_used (fn);
fn = build_call (fn, TREE_TYPE (TREE_TYPE (fn)), elems);
finish_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;
tree name_string = tinfo_name (type);
type = TREE_TYPE (type);
finish_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;
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);
}
mark_used (fn);
fn = build_call (fn, TREE_TYPE (TREE_TYPE (fn)), elems);
finish_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;
tree name_string = tinfo_name (type);
tree attrval = build_int_2 (TYPE_QUALS (type), 0);
finish_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, 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;
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);
}
mark_used (fn);
fn = build_call (fn, TREE_TYPE (TREE_TYPE (fn)), elems);
finish_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;
const char *fnname;
{
tree name_string = tinfo_name (type);
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;
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);
}
mark_used (fn);
fn = build_call (fn, TREE_TYPE (TREE_TYPE (fn)), elems);
finish_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;
tree compound_stmt;
tree if_stmt;
tree then_clause;
if (at_eof)
{
import_export_decl (fndecl);
if (DECL_REALLY_EXTERN (fndecl))
return;
}
/* Declare the static typeinfo variable. */
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);
/* Begin processing the function. */
start_function (NULL_TREE, fndecl, NULL_TREE,
SF_DEFAULT | SF_PRE_PARSED);
DECL_DEFER_OUTPUT (fndecl) = 1;
store_parm_decls ();
clear_last_expr ();
/* Begin the body of the function. */
compound_stmt = begin_compound_stmt (/*has_no_scope=*/0);
/* For convenience, we save away the address of the static
variable. */
addr = decay_conversion (tdecl);
/* If the first word of the array (the vtable) is non-zero, we've already
initialized the object, so don't do it again. */
if_stmt = begin_if_stmt ();
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);
finish_if_stmt_cond (tmp, if_stmt);
then_clause = begin_compound_stmt (/*has_no_scope=*/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_QUALS (type) != TYPE_UNQUALIFIED)
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_BASE_CONVS_MAY_REQUIRE_CODE_P (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);
finish_compound_stmt (/*has_no_scope=*/0, then_clause);
finish_then_clause (if_stmt);
finish_if_stmt ();
/* OK, now return the type_info object. */
tmp = cp_convert (build_pointer_type (type_info_type_node), addr);
tmp = build_indirect_ref (tmp, 0);
finish_return_stmt (tmp);
/* Finish the function body. */
finish_compound_stmt (/*has_no_scope=*/0, compound_stmt);
expand_body (finish_function (lineno, 0));
}