Retro68/gcc/libstdc++-v3/libsupc++/tinfo.h
2017-04-10 13:32:00 +02:00

175 lines
5.7 KiB
C++

// RTTI support internals for -*- C++ -*-
// Copyright (C) 1994-2016 Free Software Foundation, Inc.
// This file is part of GCC.
//
// GCC is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3, or (at your option)
// any later version.
// GCC is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
#include "typeinfo"
#include <cstddef>
// Class declarations shared between the typeinfo implementation files.
#include <cxxabi.h>
namespace __cxxabiv1 {
namespace {
using namespace std;
using namespace abi;
// Initial part of a vtable, this structure is used with offsetof, so we don't
// have to keep alignments consistent manually.
struct vtable_prefix
{
// Offset to most derived object.
ptrdiff_t whole_object;
// Additional padding if necessary.
#ifdef _GLIBCXX_VTABLE_PADDING
ptrdiff_t padding1;
#endif
// Pointer to most derived type_info.
const __class_type_info *whole_type;
// Additional padding if necessary.
#ifdef _GLIBCXX_VTABLE_PADDING
ptrdiff_t padding2;
#endif
// What a class's vptr points to.
const void *origin;
};
template <typename T>
inline const T *
adjust_pointer (const void *base, ptrdiff_t offset)
{
return reinterpret_cast <const T *>
(reinterpret_cast <const char *> (base) + offset);
}
// ADDR is a pointer to an object. Convert it to a pointer to a base,
// using OFFSET. IS_VIRTUAL is true, if we are getting a virtual base.
inline void const *
convert_to_base (void const *addr, bool is_virtual, ptrdiff_t offset)
{
if (is_virtual)
{
const void *vtable = *static_cast <const void *const *> (addr);
offset = *adjust_pointer<ptrdiff_t> (vtable, offset);
}
return adjust_pointer<void> (addr, offset);
}
// some predicate functions for __class_type_info::__sub_kind
inline bool contained_p (__class_type_info::__sub_kind access_path)
{
return access_path >= __class_type_info::__contained_mask;
}
inline bool public_p (__class_type_info::__sub_kind access_path)
{
return access_path & __class_type_info::__contained_public_mask;
}
inline bool virtual_p (__class_type_info::__sub_kind access_path)
{
return (access_path & __class_type_info::__contained_virtual_mask);
}
inline bool contained_public_p (__class_type_info::__sub_kind access_path)
{
return ((access_path & __class_type_info::__contained_public)
== __class_type_info::__contained_public);
}
inline bool contained_nonpublic_p (__class_type_info::__sub_kind access_path)
{
return ((access_path & __class_type_info::__contained_public)
== __class_type_info::__contained_mask);
}
inline bool contained_nonvirtual_p (__class_type_info::__sub_kind access_path)
{
return ((access_path & (__class_type_info::__contained_mask
| __class_type_info::__contained_virtual_mask))
== __class_type_info::__contained_mask);
}
static const __class_type_info *const nonvirtual_base_type =
static_cast <const __class_type_info *> (0) + 1;
} // namespace
// __upcast_result is used to hold information during traversal of a class
// hierarchy when catch matching.
struct __class_type_info::__upcast_result
{
const void *dst_ptr; // pointer to caught object
__sub_kind part2dst; // path from current base to target
int src_details; // hints about the source type hierarchy
const __class_type_info *base_type; // where we found the target,
// if in vbase the __class_type_info of vbase
// if a non-virtual base then 1
// else NULL
__upcast_result (int d)
:dst_ptr (NULL), part2dst (__unknown), src_details (d), base_type (NULL)
{}
};
// __dyncast_result is used to hold information during traversal of a class
// hierarchy when dynamic casting.
struct __class_type_info::__dyncast_result
{
const void *dst_ptr; // pointer to target object or NULL
__sub_kind whole2dst; // path from most derived object to target
__sub_kind whole2src; // path from most derived object to sub object
__sub_kind dst2src; // path from target to sub object
int whole_details; // details of the whole class hierarchy
__dyncast_result (int details_ = __vmi_class_type_info::__flags_unknown_mask)
:dst_ptr (NULL), whole2dst (__unknown),
whole2src (__unknown), dst2src (__unknown),
whole_details (details_)
{}
protected:
__dyncast_result(const __dyncast_result&);
__dyncast_result&
operator=(const __dyncast_result&);
};
inline __class_type_info::__sub_kind __class_type_info::
__find_public_src (ptrdiff_t src2dst,
const void *obj_ptr,
const __class_type_info *src_type,
const void *src_ptr) const
{
if (src2dst >= 0)
return adjust_pointer <void> (obj_ptr, src2dst) == src_ptr
? __contained_public : __not_contained;
if (src2dst == -2)
return __not_contained;
return __do_find_public_src (src2dst, obj_ptr, src_type, src_ptr);
}
}