gcc/libstdc++-v3/libsupc++/eh_throw.cc
2021-01-04 10:26:59 +01:00

135 lines
4.3 KiB
C++

// -*- C++ -*- Exception handling routines for throwing.
// Copyright (C) 2001-2021 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 "unwind-cxx.h"
#include "eh_atomics.h"
using namespace __cxxabiv1;
static void
__gxx_exception_cleanup (_Unwind_Reason_Code code, _Unwind_Exception *exc)
{
// This cleanup is set only for primaries.
__cxa_refcounted_exception *header
= __get_refcounted_exception_header_from_ue (exc);
// We only want to be called through _Unwind_DeleteException.
// _Unwind_DeleteException in the HP-UX IA64 libunwind library
// returns _URC_NO_REASON and not _URC_FOREIGN_EXCEPTION_CAUGHT
// like the GCC _Unwind_DeleteException function does.
if (code != _URC_FOREIGN_EXCEPTION_CAUGHT && code != _URC_NO_REASON)
__terminate (header->exc.terminateHandler);
if (__gnu_cxx::__eh_atomic_dec (&header->referenceCount))
{
if (header->exc.exceptionDestructor)
header->exc.exceptionDestructor (header + 1);
__cxa_free_exception (header + 1);
}
}
extern "C" __cxa_refcounted_exception*
__cxxabiv1::
__cxa_init_primary_exception(void *obj, std::type_info *tinfo,
void (_GLIBCXX_CDTOR_CALLABI *dest) (void *))
_GLIBCXX_NOTHROW
{
__cxa_refcounted_exception *header
= __get_refcounted_exception_header_from_obj (obj);
header->referenceCount = 0;
header->exc.exceptionType = tinfo;
header->exc.exceptionDestructor = dest;
header->exc.unexpectedHandler = std::get_unexpected ();
header->exc.terminateHandler = std::get_terminate ();
__GXX_INIT_PRIMARY_EXCEPTION_CLASS(header->exc.unwindHeader.exception_class);
header->exc.unwindHeader.exception_cleanup = __gxx_exception_cleanup;
return header;
}
extern "C" void
__cxxabiv1::__cxa_throw (void *obj, std::type_info *tinfo,
void (_GLIBCXX_CDTOR_CALLABI *dest) (void *))
{
PROBE2 (throw, obj, tinfo);
__cxa_eh_globals *globals = __cxa_get_globals ();
globals->uncaughtExceptions += 1;
// Definitely a primary.
__cxa_refcounted_exception *header =
__cxa_init_primary_exception(obj, tinfo, dest);
header->referenceCount = 1;
#ifdef __USING_SJLJ_EXCEPTIONS__
_Unwind_SjLj_RaiseException (&header->exc.unwindHeader);
#else
_Unwind_RaiseException (&header->exc.unwindHeader);
#endif
// Some sort of unwinding error. Note that terminate is a handler.
__cxa_begin_catch (&header->exc.unwindHeader);
std::terminate ();
}
extern "C" void
__cxxabiv1::__cxa_rethrow ()
{
__cxa_eh_globals *globals = __cxa_get_globals ();
__cxa_exception *header = globals->caughtExceptions;
globals->uncaughtExceptions += 1;
// Watch for luser rethrowing with no active exception.
if (header)
{
// Tell __cxa_end_catch this is a rethrow.
if (!__is_gxx_exception_class(header->unwindHeader.exception_class))
globals->caughtExceptions = 0;
else
{
header->handlerCount = -header->handlerCount;
// Only notify probe for C++ exceptions.
PROBE2 (rethrow, __get_object_from_ambiguous_exception(header),
header->exceptionType);
}
#ifdef __USING_SJLJ_EXCEPTIONS__
_Unwind_SjLj_Resume_or_Rethrow (&header->unwindHeader);
#else
#if defined(_LIBUNWIND_STD_ABI)
_Unwind_RaiseException (&header->unwindHeader);
#else
_Unwind_Resume_or_Rethrow (&header->unwindHeader);
#endif
#endif
// Some sort of unwinding error. Note that terminate is a handler.
__cxa_begin_catch (&header->unwindHeader);
}
std::terminate ();
}