// Methods for type_info for -*- C++ -*- Run Time Type Identification.
-// Copyright (C) 1994, 1996, 1998, 1999, 2000 Free Software Foundation
-
-// This file is part of GNU CC.
-
-// GNU CC is free software; you can redistribute it and/or modify
+// Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
+// 2003, 2004, 2005, 2006, 2007, 2009
+// Free Software Foundation
+//
+// 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 2, or (at your option)
+// the Free Software Foundation; either version 3, or (at your option)
// any later version.
-// GNU CC is distributed in the hope that it will be useful,
+// 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.
-// 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.
-
-// As a special exception, you may use this file as part of a free software
-// library without restriction. Specifically, if other files instantiate
-// templates or use macros or inline functions from this file, or you compile
-// this file and link it with other files to produce an executable, this
-// file does not by itself cause the resulting executable to be covered by
-// the GNU General Public License. This exception does not however
-// invalidate any other reasons why the executable file might be covered by
-// the GNU General Public License.
+// 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.
-#pragma implementation "typeinfo"
+// 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 <stddef.h>
+#include <bits/c++config.h>
+#include <cstddef>
#include "tinfo.h"
-#include "new" // for placement new
-
-// This file contains the minimal working set necessary to link with code
-// that uses virtual functions and -frtti but does not actually use RTTI
-// functionality.
std::type_info::
~type_info ()
{ }
-#if !defined(__GXX_ABI_VERSION) || __GXX_ABI_VERSION < 100
-// original (old) abi
-
-namespace
-{
-// ADDR is a pointer to an object. Convert it to a pointer to a base,
-// using OFFSET.
-inline void*
-convert_to_base (void *addr, bool is_virtual, myint32 offset)
-{
- if (!addr)
- return NULL;
-
- if (!is_virtual)
- return (char *) addr + offset;
-
- // Under the old ABI, the offset gives us the address of a pointer
- // to the virtual base.
- return *((void **) ((char *) addr + offset));
-}
-
-}
+#if !__GXX_TYPEINFO_EQUALITY_INLINE
// We can't rely on common symbols being shared between shared objects.
bool std::type_info::
operator== (const std::type_info& arg) const
{
- return (&arg == this) || (__builtin_strcmp (name (), arg.name ()) == 0);
-}
-
-extern "C" void
-__rtti_class (void *addr, const char *name,
- const __class_type_info::base_info *bl, size_t bn)
-{ new (addr) __class_type_info (name, bl, bn); }
-
-extern "C" void
-__rtti_si (void *addr, const char *n, const std::type_info *ti)
-{
- new (addr) __si_type_info
- (n, static_cast <const __user_type_info &> (*ti));
-}
-
-extern "C" void
-__rtti_user (void *addr, const char *name)
-{ new (addr) __user_type_info (name); }
-
-// Upcast for catch checking. OBJPTR points to the thrown object and might be
-// NULL. Return 0 on failure, non-zero on success. Set *ADJPTR to adjusted
-// object pointer.
-int __user_type_info::
-upcast (const type_info &target, void *objptr,
- void **adjptr) const
-{
- upcast_result result;
-
- if (do_upcast (contained_public, target, objptr, result))
- return 0;
- *adjptr = result.target_obj;
- return contained_public_p (result.whole2target);
-}
-
-// Down or cross cast for dynamic_cast. OBJPTR points to the most derrived
-// object, SUBPTR points to the static base object. Both must not be NULL.
-// TARGET specifies the desired target type, SUBTYPE specifies the static
-// type. Both must be defined. Returns adjusted object pointer on success,
-// NULL on failure. [expr.dynamic.cast]/8 says 'unambiguous public base'. This
-// itself is an ambiguous statement. We choose it to mean the base must be
-// separately unambiguous and public, rather than unambiguous considering only
-// public bases.
-void *__user_type_info::
-dyncast (int boff,
- const type_info &target, void *objptr,
- const type_info &subtype, void *subptr) const
-{
- dyncast_result result;
-
- do_dyncast (boff, contained_public,
- target, objptr, subtype, subptr, result);
- if (!result.target_obj)
- return NULL;
- if (contained_public_p (result.target2sub))
- return result.target_obj;
- if (contained_public_p (sub_kind (result.whole2sub & result.whole2target)))
- // Found a valid cross cast
- return result.target_obj;
- if (contained_nonvirtual_p (result.whole2sub))
- // Found an invalid cross cast, which cannot also be a down cast
- return NULL;
- if (result.target2sub == unknown)
- result.target2sub = static_cast <const __user_type_info &> (target)
- .find_public_subobj (boff, subtype,
- result.target_obj, subptr);
- if (contained_public_p (result.target2sub))
- // Found a valid down cast
- return result.target_obj;
- // Must be an invalid down cast, or the cross cast wasn't bettered
- return NULL;
-}
-
-// Catch cast helper. ACCESS_PATH is the access from the complete thrown
-// object to this base. TARGET is the desired type we want to catch. OBJPTR
-// points to this base within the throw object, it might be NULL. Fill in
-// RESULT with what we find. Return true, should we determine catch must fail.
-bool __user_type_info::
-do_upcast (sub_kind access_path,
- const type_info &target, void *objptr,
- upcast_result &__restrict result) const
-{
- if (*this == target)
- {
- result.target_obj = objptr;
- result.base_type = nonvirtual_base_type;
- result.whole2target = access_path;
- return contained_nonpublic_p (access_path);
- }
- return false;
-}
-
-// dynamic cast helper. ACCESS_PATH gives the access from the most derived
-// object to this base. TARGET indicates the desired type we want. OBJPTR
-// points to this base within the object. SUBTYPE indicates the static type
-// started from and SUBPTR points to that base within the most derived object.
-// Fill in RESULT with what we find. Return true if we have located an
-// ambiguous match.
-bool __user_type_info::
-do_dyncast (int, sub_kind access_path,
- const type_info &target, void *objptr,
- const type_info &subtype, void *subptr,
- dyncast_result &__restrict result) const
-{
- if (objptr == subptr && *this == subtype)
- {
- // The subobject we started from. Indicate how we are accessible from
- // the most derived object.
- result.whole2sub = access_path;
- return false;
- }
- if (*this == target)
- {
- result.target_obj = objptr;
- result.whole2target = access_path;
- result.target2sub = not_contained;
- return false;
- }
- return false;
-}
-
-// find_public_subobj helper. Return contained_public if we are the desired
-// subtype. OBJPTR points to this base type, SUBPTR points to the desired base
-// object.
-__user_type_info::sub_kind __user_type_info::
-do_find_public_subobj (int, const type_info &, void *objptr, void *subptr) const
-{
- if (subptr == objptr)
- // Must be our type, as the pointers match.
- return contained_public;
- return not_contained;
-}
-
-// catch helper for single public inheritance types. See
-// __user_type_info::do_upcast for semantics.
-bool __si_type_info::
-do_upcast (sub_kind access_path,
- const type_info &target, void *objptr,
- upcast_result &__restrict result) const
-{
- if (*this == target)
- {
- result.target_obj = objptr;
- result.base_type = nonvirtual_base_type;
- result.whole2target = access_path;
- return contained_nonpublic_p (access_path);
- }
- return base.do_upcast (access_path, target, objptr, result);
-}
-
-// dynamic cast helper for single public inheritance types. See
-// __user_type_info::do_dyncast for semantics. BOFF indicates how SUBTYPE
-// types are inherited by TARGET types.
-bool __si_type_info::
-do_dyncast (int boff, sub_kind access_path,
- const type_info &target, void *objptr,
- const type_info &subtype, void *subptr,
- dyncast_result &__restrict result) const
-{
- if (objptr == subptr && *this == subtype)
- {
- // The subobject we started from. Indicate how we are accessible from
- // the most derived object.
- result.whole2sub = access_path;
- return false;
- }
- if (*this == target)
- {
- result.target_obj = objptr;
- result.whole2target = access_path;
- if (boff >= 0)
- result.target2sub = ((char *)subptr - (char *)objptr) == boff
- ? contained_public : not_contained;
- else if (boff == -2)
- result.target2sub = not_contained;
- return false;
- }
- return base.do_dyncast (boff, access_path,
- target, objptr, subtype, subptr, result);
-}
-
-// find_public_subobj helper. See __user_type_info::do_find_public_subobj or
-// semantics. BOFF indicates how SUBTYPE types are inherited by the original
-// target object.
-__user_type_info::sub_kind __si_type_info::
-do_find_public_subobj (int boff, const type_info &subtype, void *objptr, void *subptr) const
-{
- if (subptr == objptr && subtype == *this)
- return contained_public;
- return base.do_find_public_subobj (boff, subtype, objptr, subptr);
-}
-
-// catch helper for multiple or non-public inheritance types. See
-// __user_type_info::do_upcast for semantics.
-bool __class_type_info::
-do_upcast (sub_kind access_path,
- const type_info &target, void *objptr,
- upcast_result &__restrict result) const
-{
- if (*this == target)
- {
- result.target_obj = objptr;
- result.base_type = nonvirtual_base_type;
- result.whole2target = access_path;
- return contained_nonpublic_p (access_path);
- }
-
- for (size_t i = n_bases; i--;)
- {
- upcast_result result2;
- void *p = objptr;
- sub_kind sub_access = access_path;
- p = convert_to_base (p,
- base_list[i].is_virtual,
- base_list[i].offset);
- if (base_list[i].is_virtual)
- sub_access = sub_kind (sub_access | contained_virtual_mask);
- if (base_list[i].access != PUBLIC)
- sub_access = sub_kind (sub_access & ~contained_public_mask);
- if (base_list[i].base->do_upcast (sub_access, target, p, result2)
- && !contained_virtual_p (result2.whole2target))
- return true; // must fail
- if (result2.base_type)
- {
- if (result2.base_type == nonvirtual_base_type
- && base_list[i].is_virtual)
- result2.base_type = base_list[i].base;
- if (!result.base_type)
- result = result2;
- else if (result.target_obj != result2.target_obj)
- {
- // Found an ambiguity.
- result.target_obj = NULL;
- result.whole2target = contained_ambig;
- return true;
- }
- else if (result.target_obj)
- {
- // Ok, found real object via a virtual path.
- result.whole2target
- = sub_kind (result.whole2target | result2.whole2target);
- }
- else
- {
- // Dealing with a null pointer, need to check vbase
- // containing each of the two choices.
- if (result2.base_type == nonvirtual_base_type
- || result.base_type == nonvirtual_base_type
- || !(*result2.base_type == *result.base_type))
- {
- // Already ambiguous, not virtual or via different virtuals.
- // Cannot match.
- result.whole2target = contained_ambig;
- return true;
- }
- result.whole2target
- = sub_kind (result.whole2target | result2.whole2target);
- }
- }
- }
- return false;
-}
-
-// dynamic cast helper for non-public or multiple inheritance types. See
-// __user_type_info::do_dyncast for overall semantics.
-// This is a big hairy function. Although the run-time behaviour of
-// dynamic_cast is simple to describe, it gives rise to some non-obvious
-// behaviour. We also desire to determine as early as possible any definite
-// answer we can get. Because it is unknown what the run-time ratio of
-// succeeding to failing dynamic casts is, we do not know in which direction
-// to bias any optimizations. To that end we make no particular effort towards
-// early fail answers or early success answers. Instead we try to minimize
-// work by filling in things lazily (when we know we need the information),
-// and opportunisticly take early success or failure results.
-bool __class_type_info::
-do_dyncast (int boff, sub_kind access_path,
- const type_info &target, void *objptr,
- const type_info &subtype, void *subptr,
- dyncast_result &__restrict result) const
-{
- if (objptr == subptr && *this == subtype)
- {
- // The subobject we started from. Indicate how we are accessible from
- // the most derived object.
- result.whole2sub = access_path;
- return false;
- }
- if (*this == target)
- {
- result.target_obj = objptr;
- result.whole2target = access_path;
- if (boff >= 0)
- result.target2sub = ((char *)subptr - (char *)objptr) == boff
- ? contained_public : not_contained;
- else if (boff == -2)
- result.target2sub = not_contained;
- return false;
- }
- bool result_ambig = false;
- for (size_t i = n_bases; i--;)
- {
- dyncast_result result2;
- void *p;
- sub_kind sub_access = access_path;
- p = convert_to_base (objptr,
- base_list[i].is_virtual,
- base_list[i].offset);
- if (base_list[i].is_virtual)
- sub_access = sub_kind (sub_access | contained_virtual_mask);
- if (base_list[i].access != PUBLIC)
- sub_access = sub_kind (sub_access & ~contained_public_mask);
-
- bool result2_ambig
- = base_list[i].base->do_dyncast (boff, sub_access,
- target, p, subtype, subptr, result2);
- result.whole2sub = sub_kind (result.whole2sub | result2.whole2sub);
- if (result2.target2sub == contained_public
- || result2.target2sub == contained_ambig)
- {
- result.target_obj = result2.target_obj;
- result.whole2target = result2.whole2target;
- result.target2sub = result2.target2sub;
- // Found a downcast which can't be bettered or an ambiguous downcast
- // which can't be disambiguated
- return result2_ambig;
- }
-
- if (!result_ambig && !result.target_obj)
- {
- // Not found anything yet.
- result.target_obj = result2.target_obj;
- result.whole2target = result2.whole2target;
- result_ambig = result2_ambig;
- }
- else if (result.target_obj && result.target_obj == result2.target_obj)
- {
- // Found at same address, must be via virtual. Pick the most
- // accessible path.
- result.whole2target =
- sub_kind (result.whole2target | result2.whole2target);
- }
- else if ((result.target_obj && result2.target_obj)
- || (result_ambig && result2.target_obj)
- || (result2_ambig && result.target_obj))
- {
- // Found two different TARGET bases, or a valid one and a set of
- // ambiguous ones, must disambiguate. See whether SUBOBJ is
- // contained publicly within one of the non-ambiguous choices.
- // If it is in only one, then that's the choice. If it is in
- // both, then we're ambiguous and fail. If it is in neither,
- // we're ambiguous, but don't yet fail as we might later find a
- // third base which does contain SUBPTR.
-
- sub_kind new_sub_kind = result2.target2sub;
- sub_kind old_sub_kind = result.target2sub;
-
- if (contained_nonvirtual_p (result.whole2sub))
- {
- // We already found SUBOBJ as a non-virtual base of most
- // derived. Therefore if it is in either choice, it can only be
- // in one of them, and we will already know.
- if (old_sub_kind == unknown)
- old_sub_kind = not_contained;
- if (new_sub_kind == unknown)
- new_sub_kind = not_contained;
- }
- else
- {
- const __user_type_info &t =
- static_cast <const __user_type_info &> (target);
-
- if (old_sub_kind >= not_contained)
- ;// already calculated
- else if (contained_nonvirtual_p (new_sub_kind))
- // Already found non-virtually inside the other choice,
- // cannot be in this.
- old_sub_kind = not_contained;
- else
- old_sub_kind = t.find_public_subobj (boff, subtype,
- result.target_obj, subptr);
-
- if (new_sub_kind >= not_contained)
- ;// already calculated
- else if (contained_nonvirtual_p (old_sub_kind))
- // Already found non-virtually inside the other choice,
- // cannot be in this.
- new_sub_kind = not_contained;
- else
- new_sub_kind = t.find_public_subobj (boff, subtype,
- result2.target_obj, subptr);
- }
-
- // Neither sub_kind can be contained_ambig -- we bail out early
- // when we find those.
- if (contained_p (sub_kind (new_sub_kind ^ old_sub_kind)))
- {
- // Only on one choice, not ambiguous.
- if (contained_p (new_sub_kind))
- {
- // Only in new.
- result.target_obj = result2.target_obj;
- result.whole2target = result2.whole2target;
- result_ambig = false;
- old_sub_kind = new_sub_kind;
- }
- result.target2sub = old_sub_kind;
- if (result.target2sub == contained_public)
- return false; // Can't be an ambiguating downcast for later discovery.
- }
- else if (contained_p (sub_kind (new_sub_kind & old_sub_kind)))
- {
- // In both.
- result.target_obj = NULL;
- result.target2sub = contained_ambig;
- return true; // Fail.
- }
- else
- {
- // In neither publicly, ambiguous for the moment, but keep
- // looking. It is possible that it was private in one or
- // both and therefore we should fail, but that's just tough.
- result.target_obj = NULL;
- result.target2sub = not_contained;
- result_ambig = true;
- }
- }
-
- if (result.whole2sub == contained_private)
- // We found SUBOBJ as a private non-virtual base, therefore all
- // cross casts will fail. We have already found a down cast, if
- // there is one.
- return result_ambig;
- }
-
- return result_ambig;
+#if __GXX_MERGED_TYPEINFO_NAMES
+ return name () == arg.name ();
+#else
+ return (&arg == this)
+ || (name ()[0] != '*' && (__builtin_strcmp (name (), arg.name ()) == 0));
+#endif
}
-// find_public_subobj helper for non-public or multiple inheritance types. See
-// __user_type_info::do_find_public_subobj for semantics. We make use of BOFF
-// to prune the base class walk.
-__user_type_info::sub_kind __class_type_info::
-do_find_public_subobj (int boff, const type_info &subtype, void *objptr, void *subptr) const
-{
- if (objptr == subptr && subtype == *this)
- return contained_public;
-
- for (size_t i = n_bases; i--;)
- {
- if (base_list[i].access != PUBLIC)
- continue; // Not public, can't be here.
- void *p;
-
- if (base_list[i].is_virtual && boff == -3)
- // Not a virtual base, so can't be here.
- continue;
-
- p = convert_to_base (objptr,
- base_list[i].is_virtual,
- base_list[i].offset);
-
- sub_kind base_kind = base_list[i].base->do_find_public_subobj
- (boff, subtype, p, subptr);
- if (contained_p (base_kind))
- {
- if (base_list[i].is_virtual)
- base_kind = sub_kind (base_kind | contained_virtual_mask);
- return base_kind;
- }
- }
-
- return not_contained;
-}
-#else
-// new abi
+#endif
namespace std {
return false;
}
-};
-
-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 {
- ptrdiff_t whole_object; // offset to most derived object
- const __class_type_info *whole_type; // pointer to most derived type_info
- const void *origin; // what a class's vptr points to
-};
-
-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
-
-namespace __cxxabiv1
-{
-
-__class_type_info::
-~__class_type_info ()
-{}
-
-__si_class_type_info::
-~__si_class_type_info ()
-{}
-
-__vmi_class_type_info::
-~__vmi_class_type_info ()
-{}
-
-// __upcast_result is used to hold information during traversal of a class
-// heirarchy 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 heirarchy
- 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
- public:
- __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
-// heirarchy 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 heirarchy
-
- public:
- __dyncast_result (int details_ = __vmi_class_type_info::__flags_unknown_mask)
- :dst_ptr (NULL), whole2dst (__unknown),
- whole2src (__unknown), dst2src (__unknown),
- whole_details (details_)
- {}
-};
-
-bool __class_type_info::
-__do_catch (const type_info *thr_type,
- void **thr_obj,
- unsigned outer) const
-{
- if (*this == *thr_type)
- return true;
- if (outer >= 4)
- // Neither `A' nor `A *'.
- return false;
- return thr_type->__do_upcast (this, thr_obj);
-}
-
-bool __class_type_info::
-__do_upcast (const __class_type_info *dst_type,
- void **obj_ptr) const
-{
- __upcast_result result (__vmi_class_type_info::__flags_unknown_mask);
-
- __do_upcast (dst_type, *obj_ptr, result);
- if (!contained_public_p (result.part2dst))
- return false;
- *obj_ptr = const_cast <void *> (result.dst_ptr);
- return true;
-}
-
-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);
-}
-
-__class_type_info::__sub_kind __class_type_info::
-__do_find_public_src (ptrdiff_t,
- const void *obj_ptr,
- const __class_type_info *,
- const void *src_ptr) const
-{
- if (src_ptr == obj_ptr)
- // Must be our type, as the pointers match.
- return __contained_public;
- return __not_contained;
-}
-
-__class_type_info::__sub_kind __si_class_type_info::
-__do_find_public_src (ptrdiff_t src2dst,
- const void *obj_ptr,
- const __class_type_info *src_type,
- const void *src_ptr) const
-{
- if (src_ptr == obj_ptr && *this == *src_type)
- return __contained_public;
- return __base_type->__do_find_public_src (src2dst, obj_ptr, src_type, src_ptr);
-}
-
-__class_type_info::__sub_kind __vmi_class_type_info::
-__do_find_public_src (ptrdiff_t src2dst,
- const void *obj_ptr,
- const __class_type_info *src_type,
- const void *src_ptr) const
-{
- if (obj_ptr == src_ptr && *this == *src_type)
- return __contained_public;
-
- for (size_t i = __base_count; i--;)
- {
- if (!__base_info[i].__is_public_p ())
- continue; // Not public, can't be here.
-
- const void *base = obj_ptr;
- ptrdiff_t offset = __base_info[i].__offset ();
- bool is_virtual = __base_info[i].__is_virtual_p ();
-
- if (is_virtual)
- {
- if (src2dst == -3)
- continue; // Not a virtual base, so can't be here.
- }
- base = convert_to_base (base, is_virtual, offset);
-
- __sub_kind base_kind = __base_info[i].__base->__do_find_public_src
- (src2dst, base, src_type, src_ptr);
- if (contained_p (base_kind))
- {
- if (is_virtual)
- base_kind = __sub_kind (base_kind | __contained_virtual_mask);
- return base_kind;
- }
- }
-
- return __not_contained;
-}
-
-bool __class_type_info::
-__do_dyncast (ptrdiff_t,
- __sub_kind access_path,
- const __class_type_info *dst_type,
- const void *obj_ptr,
- const __class_type_info *src_type,
- const void *src_ptr,
- __dyncast_result &__restrict result) const
-{
- if (obj_ptr == src_ptr && *this == *src_type)
- {
- // The src object we started from. Indicate how we are accessible from
- // the most derived object.
- result.whole2src = access_path;
- return false;
- }
- if (*this == *dst_type)
- {
- result.dst_ptr = obj_ptr;
- result.whole2dst = access_path;
- result.dst2src = __not_contained;
- return false;
- }
- return false;
-}
-
-bool __si_class_type_info::
-__do_dyncast (ptrdiff_t src2dst,
- __sub_kind access_path,
- const __class_type_info *dst_type,
- const void *obj_ptr,
- const __class_type_info *src_type,
- const void *src_ptr,
- __dyncast_result &__restrict result) const
-{
- if (*this == *dst_type)
- {
- result.dst_ptr = obj_ptr;
- result.whole2dst = access_path;
- if (src2dst >= 0)
- result.dst2src = adjust_pointer <void> (obj_ptr, src2dst) == src_ptr
- ? __contained_public : __not_contained;
- else if (src2dst == -2)
- result.dst2src = __not_contained;
- return false;
- }
- if (obj_ptr == src_ptr && *this == *src_type)
- {
- // The src object we started from. Indicate how we are accessible from
- // the most derived object.
- result.whole2src = access_path;
- return false;
- }
- return __base_type->__do_dyncast (src2dst, access_path, dst_type, obj_ptr,
- src_type, src_ptr, result);
-}
-
-// This is a big hairy function. Although the run-time behaviour of
-// dynamic_cast is simple to describe, it gives rise to some non-obvious
-// behaviour. We also desire to determine as early as possible any definite
-// answer we can get. Because it is unknown what the run-time ratio of
-// succeeding to failing dynamic casts is, we do not know in which direction
-// to bias any optimizations. To that end we make no particular effort towards
-// early fail answers or early success answers. Instead we try to minimize
-// work by filling in things lazily (when we know we need the information),
-// and opportunisticly take early success or failure results.
-bool __vmi_class_type_info::
-__do_dyncast (ptrdiff_t src2dst,
- __sub_kind access_path,
- const __class_type_info *dst_type,
- const void *obj_ptr,
- const __class_type_info *src_type,
- const void *src_ptr,
- __dyncast_result &__restrict result) const
-{
- if (result.whole_details & __flags_unknown_mask)
- result.whole_details = __flags;
-
- if (obj_ptr == src_ptr && *this == *src_type)
- {
- // The src object we started from. Indicate how we are accessible from
- // the most derived object.
- result.whole2src = access_path;
- return false;
- }
- if (*this == *dst_type)
- {
- result.dst_ptr = obj_ptr;
- result.whole2dst = access_path;
- if (src2dst >= 0)
- result.dst2src = adjust_pointer <void> (obj_ptr, src2dst) == src_ptr
- ? __contained_public : __not_contained;
- else if (src2dst == -2)
- result.dst2src = __not_contained;
- return false;
- }
-
- bool result_ambig = false;
- for (size_t i = __base_count; i--;)
- {
- __dyncast_result result2 (result.whole_details);
- void const *base = obj_ptr;
- __sub_kind base_access = access_path;
- ptrdiff_t offset = __base_info[i].__offset ();
- bool is_virtual = __base_info[i].__is_virtual_p ();
-
- if (is_virtual)
- base_access = __sub_kind (base_access | __contained_virtual_mask);
- base = convert_to_base (base, is_virtual, offset);
-
- if (!__base_info[i].__is_public_p ())
- {
- if (src2dst == -2 &&
- !(result.whole_details
- & (__non_diamond_repeat_mask | __diamond_shaped_mask)))
- // The hierarchy has no duplicate bases (which might ambiguate
- // things) and where we started is not a public base of what we
- // want (so it cannot be a downcast). There is nothing of interest
- // hiding in a non-public base.
- continue;
- base_access = __sub_kind (base_access & ~__contained_public_mask);
- }
-
- bool result2_ambig
- = __base_info[i].__base->__do_dyncast (src2dst, base_access,
- dst_type, base,
- src_type, src_ptr, result2);
- result.whole2src = __sub_kind (result.whole2src | result2.whole2src);
- if (result2.dst2src == __contained_public
- || result2.dst2src == __contained_ambig)
- {
- result.dst_ptr = result2.dst_ptr;
- result.whole2dst = result2.whole2dst;
- result.dst2src = result2.dst2src;
- // Found a downcast which can't be bettered or an ambiguous downcast
- // which can't be disambiguated
- return result2_ambig;
- }
-
- if (!result_ambig && !result.dst_ptr)
- {
- // Not found anything yet.
- result.dst_ptr = result2.dst_ptr;
- result.whole2dst = result2.whole2dst;
- result_ambig = result2_ambig;
- if (result.dst_ptr && result.whole2src != __unknown
- && !(__flags & __non_diamond_repeat_mask))
- // Found dst and src and we don't have repeated bases.
- return result_ambig;
- }
- else if (result.dst_ptr && result.dst_ptr == result2.dst_ptr)
- {
- // Found at same address, must be via virtual. Pick the most
- // accessible path.
- result.whole2dst =
- __sub_kind (result.whole2dst | result2.whole2dst);
- }
- else if ((result.dst_ptr != 0 | result_ambig)
- && (result2.dst_ptr != 0 | result2_ambig))
- {
- // Found two different DST_TYPE bases, or a valid one and a set of
- // ambiguous ones, must disambiguate. See whether SRC_PTR is
- // contained publicly within one of the non-ambiguous choices. If it
- // is in only one, then that's the choice. If it is in both, then
- // we're ambiguous and fail. If it is in neither, we're ambiguous,
- // but don't yet fail as we might later find a third base which does
- // contain SRC_PTR.
-
- __sub_kind new_sub_kind = result2.dst2src;
- __sub_kind old_sub_kind = result.dst2src;
-
- if (contained_p (result.whole2src)
- && (!virtual_p (result.whole2src)
- || !(result.whole_details & __diamond_shaped_mask)))
- {
- // We already found SRC_PTR as a base of most derived, and
- // either it was non-virtual, or the whole heirarchy is
- // not-diamond shaped. Therefore if it is in either choice, it
- // can only be in one of them, and we will already know.
- if (old_sub_kind == __unknown)
- old_sub_kind = __not_contained;
- if (new_sub_kind == __unknown)
- new_sub_kind = __not_contained;
- }
- else
- {
- if (old_sub_kind >= __not_contained)
- ;// already calculated
- else if (contained_p (new_sub_kind)
- && (!virtual_p (new_sub_kind)
- || !(__flags & __diamond_shaped_mask)))
- // Already found inside the other choice, and it was
- // non-virtual or we are not diamond shaped.
- old_sub_kind = __not_contained;
- else
- old_sub_kind = dst_type->__find_public_src
- (src2dst, result.dst_ptr, src_type, src_ptr);
-
- if (new_sub_kind >= __not_contained)
- ;// already calculated
- else if (contained_p (old_sub_kind)
- && (!virtual_p (old_sub_kind)
- || !(__flags & __diamond_shaped_mask)))
- // Already found inside the other choice, and it was
- // non-virtual or we are not diamond shaped.
- new_sub_kind = __not_contained;
- else
- new_sub_kind = dst_type->__find_public_src
- (src2dst, result2.dst_ptr, src_type, src_ptr);
- }
-
- // Neither sub_kind can be contained_ambig -- we bail out early
- // when we find those.
- if (contained_p (__sub_kind (new_sub_kind ^ old_sub_kind)))
- {
- // Only on one choice, not ambiguous.
- if (contained_p (new_sub_kind))
- {
- // Only in new.
- result.dst_ptr = result2.dst_ptr;
- result.whole2dst = result2.whole2dst;
- result_ambig = false;
- old_sub_kind = new_sub_kind;
- }
- result.dst2src = old_sub_kind;
- if (public_p (result.dst2src))
- return false; // Can't be an ambiguating downcast for later discovery.
- if (!virtual_p (result.dst2src))
- return false; // Found non-virtually can't be bettered
- }
- else if (contained_p (__sub_kind (new_sub_kind & old_sub_kind)))
- {
- // In both.
- result.dst_ptr = NULL;
- result.dst2src = __contained_ambig;
- return true; // Fail.
- }
- else
- {
- // In neither publicly, ambiguous for the moment, but keep
- // looking. It is possible that it was private in one or
- // both and therefore we should fail, but that's just tough.
- result.dst_ptr = NULL;
- result.dst2src = __not_contained;
- result_ambig = true;
- }
- }
-
- if (result.whole2src == __contained_private)
- // We found SRC_PTR as a private non-virtual base, therefore all
- // cross casts will fail. We have already found a down cast, if
- // there is one.
- return result_ambig;
- }
-
- return result_ambig;
-}
-
-bool __class_type_info::
-__do_upcast (const __class_type_info *dst, const void *obj,
- __upcast_result &__restrict result) const
-{
- if (*this == *dst)
- {
- result.dst_ptr = obj;
- result.base_type = nonvirtual_base_type;
- result.part2dst = __contained_public;
- return true;
- }
- return false;
-}
-
-bool __si_class_type_info::
-__do_upcast (const __class_type_info *dst, const void *obj_ptr,
- __upcast_result &__restrict result) const
-{
- if (__class_type_info::__do_upcast (dst, obj_ptr, result))
- return true;
-
- return __base_type->__do_upcast (dst, obj_ptr, result);
-}
-
-bool __vmi_class_type_info::
-__do_upcast (const __class_type_info *dst, const void *obj_ptr,
- __upcast_result &__restrict result) const
-{
- if (__class_type_info::__do_upcast (dst, obj_ptr, result))
- return true;
-
- int src_details = result.src_details;
- if (src_details & __flags_unknown_mask)
- src_details = __flags;
-
- for (size_t i = __base_count; i--;)
- {
- __upcast_result result2 (src_details);
- const void *base = obj_ptr;
- ptrdiff_t offset = __base_info[i].__offset ();
- bool is_virtual = __base_info[i].__is_virtual_p ();
- bool is_public = __base_info[i].__is_public_p ();
-
- if (!is_public && !(src_details & __non_diamond_repeat_mask))
- // original cannot have an ambiguous base, so skip private bases
- continue;
-
- if (base)
- base = convert_to_base (base, is_virtual, offset);
-
- if (__base_info[i].__base->__do_upcast (dst, base, result2))
- {
- if (result2.base_type == nonvirtual_base_type && is_virtual)
- result2.base_type = __base_info[i].__base;
- if (contained_p (result2.part2dst) && !is_public)
- result2.part2dst = __sub_kind (result2.part2dst & ~__contained_public_mask);
-
- if (!result.base_type)
- {
- result = result2;
- if (!contained_p (result.part2dst))
- return true; // found ambiguously
-
- if (result.part2dst & __contained_public_mask)
- {
- if (!(__flags & __non_diamond_repeat_mask))
- return true; // cannot have an ambiguous other base
- }
- else
- {
- if (!virtual_p (result.part2dst))
- return true; // cannot have another path
- if (!(__flags & __diamond_shaped_mask))
- return true; // cannot have a more accessible path
- }
- }
- else if (result.dst_ptr != result2.dst_ptr)
- {
- // Found an ambiguity.
- result.dst_ptr = NULL;
- result.part2dst = __contained_ambig;
- return true;
- }
- else if (result.dst_ptr)
- {
- // Ok, found real object via a virtual path.
- result.part2dst
- = __sub_kind (result.part2dst | result2.part2dst);
- }
- else
- {
- // Dealing with a null pointer, need to check vbase
- // containing each of the two choices.
- if (result2.base_type == nonvirtual_base_type
- || result.base_type == nonvirtual_base_type
- || !(*result2.base_type == *result.base_type))
- {
- // Already ambiguous, not virtual or via different virtuals.
- // Cannot match.
- result.part2dst = __contained_ambig;
- return true;
- }
- result.part2dst
- = __sub_kind (result.part2dst | result2.part2dst);
- }
- }
- }
- return result.part2dst != __unknown;
-}
-
-// this is the external interface to the dynamic cast machinery
-extern "C" void *
-__dynamic_cast (const void *src_ptr, // object started from
- const __class_type_info *src_type, // type of the starting object
- const __class_type_info *dst_type, // desired target type
- ptrdiff_t src2dst) // how src and dst are related
-{
- const void *vtable = *static_cast <const void *const *> (src_ptr);
- const vtable_prefix *prefix =
- adjust_pointer <vtable_prefix> (vtable,
- -offsetof (vtable_prefix, origin));
- const void *whole_ptr =
- adjust_pointer <void> (src_ptr, prefix->whole_object);
- const __class_type_info *whole_type = prefix->whole_type;
- __class_type_info::__dyncast_result result;
-
- whole_type->__do_dyncast (src2dst, __class_type_info::__contained_public,
- dst_type, whole_ptr, src_type, src_ptr, result);
- if (!result.dst_ptr)
- return NULL;
- if (contained_public_p (result.dst2src))
- // Src is known to be a public base of dst.
- return const_cast <void *> (result.dst_ptr);
- if (contained_public_p (__class_type_info::__sub_kind (result.whole2src & result.whole2dst)))
- // Both src and dst are known to be public bases of whole. Found a valid
- // cross cast.
- return const_cast <void *> (result.dst_ptr);
- if (contained_nonvirtual_p (result.whole2src))
- // Src is known to be a non-public nonvirtual base of whole, and not a
- // base of dst. Found an invalid cross cast, which cannot also be a down
- // cast
- return NULL;
- if (result.dst2src == __class_type_info::__unknown)
- result.dst2src = dst_type->__find_public_src (src2dst, result.dst_ptr,
- src_type, src_ptr);
- if (contained_public_p (result.dst2src))
- // Found a valid down cast
- return const_cast <void *> (result.dst_ptr);
- // Must be an invalid down cast, or the cross cast wasn't bettered
- return NULL;
-}
-
-}; // namespace __cxxabiv1
-#endif
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