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- // -*- C++ -*- Exception handling routines for catching.
- // Copyright (C) 2001-2022 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 <cstdlib>
- #include "unwind-cxx.h"
- using namespace __cxxabiv1;
- extern "C" void *
- __cxxabiv1::__cxa_get_exception_ptr(void *exc_obj_in) _GLIBCXX_NOTHROW
- {
- _Unwind_Exception *exceptionObject
- = reinterpret_cast <_Unwind_Exception *>(exc_obj_in);
- return __gxx_caught_object(exceptionObject);
- }
- extern "C" void *
- __cxxabiv1::__cxa_begin_catch (void *exc_obj_in) _GLIBCXX_NOTHROW
- {
- _Unwind_Exception *exceptionObject
- = reinterpret_cast <_Unwind_Exception *>(exc_obj_in);
- __cxa_eh_globals *globals = __cxa_get_globals ();
- __cxa_exception *prev = globals->caughtExceptions;
- __cxa_exception *header = __get_exception_header_from_ue (exceptionObject);
- void* objectp;
- // Foreign exceptions can't be stacked here. If the exception stack is
- // empty, then fine. Otherwise we really have no choice but to terminate.
- // Note that this use of "header" is a lie. It's fine so long as we only
- // examine header->unwindHeader though.
- if (!__is_gxx_exception_class(header->unwindHeader.exception_class))
- {
- if (prev != 0)
- std::terminate ();
- // Remember for end_catch and rethrow.
- globals->caughtExceptions = header;
- // ??? No sensible value to return; we don't know what the
- // object is, much less where it is in relation to the header.
- return 0;
- }
- int count = header->handlerCount;
- // Count is less than zero if this exception was rethrown from an
- // immediately enclosing region.
- if (count < 0)
- count = -count + 1;
- else
- count += 1;
- header->handlerCount = count;
- globals->uncaughtExceptions -= 1;
- if (header != prev)
- {
- header->nextException = prev;
- globals->caughtExceptions = header;
- }
- objectp = __gxx_caught_object(exceptionObject);
- PROBE2 (catch, objectp, header->exceptionType);
- #ifdef __ARM_EABI_UNWINDER__
- _Unwind_Complete(exceptionObject);
- #endif
- return objectp;
- }
- extern "C" void
- __cxxabiv1::__cxa_end_catch ()
- {
- __cxa_eh_globals *globals = __cxa_get_globals_fast ();
- __cxa_exception *header = globals->caughtExceptions;
- // A rethrow of a foreign exception will be removed from the
- // the exception stack immediately by __cxa_rethrow.
- if (!header)
- return;
- // A foreign exception couldn't have been stacked (see above),
- // so by definition processing must be complete.
- if (!__is_gxx_exception_class(header->unwindHeader.exception_class))
- {
- globals->caughtExceptions = 0;
- _Unwind_DeleteException (&header->unwindHeader);
- return;
- }
- int count = header->handlerCount;
- if (count < 0)
- {
- // This exception was rethrown. Decrement the (inverted) catch
- // count and remove it from the chain when it reaches zero.
- if (++count == 0)
- globals->caughtExceptions = header->nextException;
- }
- else if (--count == 0)
- {
- // Handling for this exception is complete. Destroy the object.
- globals->caughtExceptions = header->nextException;
- _Unwind_DeleteException (&header->unwindHeader);
- return;
- }
- else if (count < 0)
- // A bug in the exception handling library or compiler.
- std::terminate ();
- header->handlerCount = count;
- }
- bool
- std::uncaught_exception() throw()
- {
- #if __cpp_exceptions
- __cxa_eh_globals *globals = __cxa_get_globals ();
- return globals->uncaughtExceptions != 0;
- #else
- return false;
- #endif
- }
- int
- std::uncaught_exceptions() throw()
- {
- #if __cpp_exceptions
- __cxa_eh_globals *globals = __cxa_get_globals ();
- return globals->uncaughtExceptions;
- #else
- return 0;
- #endif
- }
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