Retro68/gcc/libstdc++-v3/libsupc++/eh_call.cc
2018-12-28 16:30:48 +01:00

162 lines
5.0 KiB
C++

// -*- C++ -*- Helpers for calling unextected and terminate
// Copyright (C) 2001-2018 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 <bits/c++config.h>
#include <cstdlib>
#include <bits/exception_defines.h>
#include "unwind-cxx.h"
using namespace __cxxabiv1;
#include "unwind-pe.h"
// Helper routine for when the exception handling code needs to call
// terminate.
extern "C" void
__cxa_call_terminate(_Unwind_Exception* ue_header) throw ()
{
if (ue_header)
{
// terminate is classed as a catch handler.
__cxa_begin_catch(ue_header);
// Call the terminate handler that was in effect when we threw this
// exception. */
if (__is_gxx_exception_class(ue_header->exception_class))
{
__cxa_exception* xh;
xh = __get_exception_header_from_ue(ue_header);
__terminate(xh->terminateHandler);
}
}
/* Call the global routine if we don't have anything better. */
std::terminate();
}
#ifdef __ARM_EABI_UNWINDER__
// The ARM EABI __cxa_call_unexpected has the same semantics as the generic
// routine, but the exception specification has a different format.
extern "C" void
__cxa_call_unexpected(void* exc_obj_in)
{
_Unwind_Exception* exc_obj
= reinterpret_cast<_Unwind_Exception*>(exc_obj_in);
int rtti_count = 0;
_Unwind_Word rtti_stride = 0;
_Unwind_Word* rtti_list = NULL;
_Unwind_Ptr rtti_base = 0;
bool foreign_exception;
std::unexpected_handler unexpectedHandler = NULL;
std::terminate_handler terminateHandler = NULL;
__cxa_exception* xh;
if (__is_gxx_exception_class(exc_obj->exception_class))
{
// Save data from the EO, which may be clobbered by _cxa_begin_catch.
xh = __get_exception_header_from_ue(exc_obj);
unexpectedHandler = xh->unexpectedHandler;
terminateHandler = xh->terminateHandler;
rtti_count = exc_obj->barrier_cache.bitpattern[1];
rtti_base = (_Unwind_Ptr) exc_obj->barrier_cache.bitpattern[2];
rtti_stride = exc_obj->barrier_cache.bitpattern[3];
rtti_list = (_Unwind_Word*) exc_obj->barrier_cache.bitpattern[4];
foreign_exception = false;
}
else
foreign_exception = true;
/* This must be called after extracting data from the EO, but before
calling unexpected(). */
__cxa_begin_catch(exc_obj);
// This function is a handler for our exception argument. If we exit
// by throwing a different exception, we'll need the original cleaned up.
struct end_catch_protect
{
end_catch_protect() { }
~end_catch_protect() { __cxa_end_catch(); }
} end_catch_protect_obj;
__try
{
if (foreign_exception)
std::unexpected();
else
__unexpected(unexpectedHandler);
}
__catch(...)
{
/* See if the new exception matches the rtti list. */
if (foreign_exception)
std::terminate();
// Get the exception thrown from unexpected.
__cxa_eh_globals* globals = __cxa_get_globals_fast();
__cxa_exception* new_xh = globals->caughtExceptions;
void* new_ptr = __get_object_from_ambiguous_exception (new_xh);
const std::type_info* catch_type;
int n;
bool bad_exception_allowed = false;
const std::type_info& bad_exc = typeid(std::bad_exception);
// Check the new exception against the rtti list
for (n = 0; n < rtti_count; n++)
{
_Unwind_Word offset;
offset = (_Unwind_Word) &rtti_list[n * (rtti_stride >> 2)];
offset = _Unwind_decode_typeinfo_ptr(rtti_base, offset);
catch_type = (const std::type_info*) (offset);
if (__cxa_type_match(&new_xh->unwindHeader, catch_type, false,
&new_ptr) != ctm_failed)
__throw_exception_again;
// If the exception spec allows std::bad_exception, throw that.
// We don't have a thrown object to compare against, but since
// bad_exception doesn't have virtual bases, that's OK; just pass NULL.
void* obj = NULL;
if (catch_type->__do_catch(&bad_exc, &obj, 1))
bad_exception_allowed = true;
}
// If the exception spec allows std::bad_exception, throw that.
#if __cpp_exceptions
if (bad_exception_allowed)
throw std::bad_exception();
#endif
// Otherwise, die.
__terminate(terminateHandler);
}
}
#endif // __ARM_EABI_UNWINDER__