contrib/gcc-8.0/libstdc++-v3/libsupc++/class_type_info.cc

   1 // Copyright (C) 1994-2018 Free Software Foundation, Inc.
   2 //
   3 // This file is part of GCC.
   4 //
   5 // GCC is free software; you can redistribute it and/or modify
   6 // it under the terms of the GNU General Public License as published by
   7 // the Free Software Foundation; either version 3, or (at your option)
   8 // any later version.
   9
  10 // GCC is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14
  15 // Under Section 7 of GPL version 3, you are granted additional
  16 // permissions described in the GCC Runtime Library Exception, version
  17 // 3.1, as published by the Free Software Foundation.
  18
  19 // You should have received a copy of the GNU General Public License and
  20 // a copy of the GCC Runtime Library Exception along with this program;
  21 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  22 // <http://www.gnu.org/licenses/>.
  23
  24 #include "tinfo.h"
  25
  26 namespace __cxxabiv1 {
  27
  28 __class_type_info::
  29 ~__class_type_info ()
  30 {}
  31
  32 bool __class_type_info::
  33 __do_catch (const type_info *thr_type,
  34             void **thr_obj,
  35             unsigned outer) const
  36 {
  37   if (*this == *thr_type)
  38     return true;
  39   if (outer >= 4)
  40     // Neither `A' nor `A *'.
  41     return false;
  42   return thr_type->__do_upcast (this, thr_obj);
  43 }
  44
  45 bool __class_type_info::
  46 __do_upcast (const __class_type_info *dst_type,
  47              void **obj_ptr) const
  48 {
  49   __upcast_result result (__vmi_class_type_info::__flags_unknown_mask);
  50
  51   __do_upcast (dst_type, *obj_ptr, result);
  52   if (!contained_public_p (result.part2dst))
  53     return false;
  54   *obj_ptr = const_cast <void *> (result.dst_ptr);
  55   return true;
  56 }
  57
  58 __class_type_info::__sub_kind __class_type_info::
  59 __do_find_public_src (ptrdiff_t,
  60                       const void *obj_ptr,
  61                       const __class_type_info *,
  62                       const void *src_ptr) const
  63 {
  64   if (src_ptr == obj_ptr)
  65     // Must be our type, as the pointers match.
  66     return __contained_public;
  67   return __not_contained;
  68 }
  69
  70 bool __class_type_info::
  71 __do_dyncast (ptrdiff_t,
  72               __sub_kind access_path,
  73               const __class_type_info *dst_type,
  74               const void *obj_ptr,
  75               const __class_type_info *src_type,
  76               const void *src_ptr,
  77               __dyncast_result &__restrict result) const
  78 {
  79   if (obj_ptr == src_ptr && *this == *src_type)
  80     {
  81       // The src object we started from. Indicate how we are accessible from
  82       // the most derived object.
  83       result.whole2src = access_path;
  84       return false;
  85     }
  86   if (*this == *dst_type)
  87     {
  88       result.dst_ptr = obj_ptr;
  89       result.whole2dst = access_path;
  90       result.dst2src = __not_contained;
  91       return false;
  92     }
  93   return false;
  94 }
  95
  96 bool __class_type_info::
  97 __do_upcast (const __class_type_info *dst, const void *obj,
  98              __upcast_result &__restrict result) const
  99 {
 100   if (*this == *dst)
 101     {
 102       result.dst_ptr = obj;
 103       result.base_type = nonvirtual_base_type;
 104       result.part2dst = __contained_public;
 105       return true;
 106     }
 107   return false;
 108 }
 109
 110 }