X-Git-Url: https://oss.titaniummirror.com/gitweb?a=blobdiff_plain;f=libstdc%2B%2B-v3%2Flibsupc%2B%2B%2Fdyncast.cc;fp=libstdc%2B%2B-v3%2Flibsupc%2B%2B%2Fdyncast.cc;h=f565ed459fe464a0179382212cc21bc5316110ab;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git diff --git a/libstdc++-v3/libsupc++/dyncast.cc b/libstdc++-v3/libsupc++/dyncast.cc new file mode 100644 index 00000000..f565ed45 --- /dev/null +++ b/libstdc++-v3/libsupc++/dyncast.cc @@ -0,0 +1,72 @@ +// Copyright (C) 1994, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 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 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 +// . + +#include "tinfo.h" + +namespace __cxxabiv1 { + + +// 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 (src_ptr); + const vtable_prefix *prefix = + adjust_pointer (vtable, + -offsetof (vtable_prefix, origin)); + const void *whole_ptr = + adjust_pointer (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 (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 (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 (result.dst_ptr); + // Must be an invalid down cast, or the cross cast wasn't bettered + return NULL; +} + +}