159 lines
4.5 KiB
C++
159 lines
4.5 KiB
C++
// -*- C++ -*- Allocate exception objects.
|
|
// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006
|
|
// 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 2, 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.
|
|
//
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with GCC; see the file COPYING. If not, write to
|
|
// the Free Software Foundation, 51 Franklin Street, Fifth Floor,
|
|
// Boston, MA 02110-1301, USA.
|
|
|
|
// As a special exception, you may use this file as part of a free software
|
|
// library without restriction. Specifically, if other files instantiate
|
|
// templates or use macros or inline functions from this file, or you compile
|
|
// this file and link it with other files to produce an executable, this
|
|
// file does not by itself cause the resulting executable to be covered by
|
|
// the GNU General Public License. This exception does not however
|
|
// invalidate any other reasons why the executable file might be covered by
|
|
// the GNU General Public License.
|
|
|
|
// This is derived from the C++ ABI for IA-64. Where we diverge
|
|
// for cross-architecture compatibility are noted with "@@@".
|
|
|
|
#include <bits/c++config.h>
|
|
#include <cstdlib>
|
|
#if _GLIBCXX_HOSTED
|
|
#include <cstring>
|
|
#endif
|
|
#include <climits>
|
|
#include <exception>
|
|
#include "unwind-cxx.h"
|
|
#include <ext/concurrence.h>
|
|
|
|
#if _GLIBCXX_HOSTED
|
|
using std::free;
|
|
using std::malloc;
|
|
using std::memset;
|
|
#else
|
|
// In a freestanding environment, these functions may not be available
|
|
// -- but for now, we assume that they are.
|
|
extern "C" void *malloc (std::size_t);
|
|
extern "C" void free(void *);
|
|
extern "C" void *memset (void *, int, std::size_t);
|
|
#endif
|
|
|
|
using namespace __cxxabiv1;
|
|
|
|
// ??? How to control these parameters.
|
|
|
|
// Guess from the size of basic types how large a buffer is reasonable.
|
|
// Note that the basic c++ exception header has 13 pointers and 2 ints,
|
|
// so on a system with PSImode pointers we're talking about 56 bytes
|
|
// just for overhead.
|
|
|
|
#if INT_MAX == 32767
|
|
# define EMERGENCY_OBJ_SIZE 128
|
|
# define EMERGENCY_OBJ_COUNT 16
|
|
#elif LONG_MAX == 2147483647
|
|
# define EMERGENCY_OBJ_SIZE 512
|
|
# define EMERGENCY_OBJ_COUNT 32
|
|
#else
|
|
# define EMERGENCY_OBJ_SIZE 1024
|
|
# define EMERGENCY_OBJ_COUNT 64
|
|
#endif
|
|
|
|
#ifndef __GTHREADS
|
|
# undef EMERGENCY_OBJ_COUNT
|
|
# define EMERGENCY_OBJ_COUNT 4
|
|
#endif
|
|
|
|
#if INT_MAX == 32767 || EMERGENCY_OBJ_COUNT <= 32
|
|
typedef unsigned int bitmask_type;
|
|
#else
|
|
typedef unsigned long bitmask_type;
|
|
#endif
|
|
|
|
|
|
typedef char one_buffer[EMERGENCY_OBJ_SIZE] __attribute__((aligned));
|
|
static one_buffer emergency_buffer[EMERGENCY_OBJ_COUNT];
|
|
static bitmask_type emergency_used;
|
|
|
|
namespace
|
|
{
|
|
// A single mutex controlling emergency allocations.
|
|
__gnu_cxx::__mutex emergency_mutex;
|
|
}
|
|
|
|
extern "C" void *
|
|
__cxxabiv1::__cxa_allocate_exception(std::size_t thrown_size) throw()
|
|
{
|
|
void *ret;
|
|
|
|
thrown_size += sizeof (__cxa_exception);
|
|
ret = malloc (thrown_size);
|
|
|
|
if (! ret)
|
|
{
|
|
__gnu_cxx::__scoped_lock sentry(emergency_mutex);
|
|
|
|
bitmask_type used = emergency_used;
|
|
unsigned int which = 0;
|
|
|
|
if (thrown_size > EMERGENCY_OBJ_SIZE)
|
|
goto failed;
|
|
while (used & 1)
|
|
{
|
|
used >>= 1;
|
|
if (++which >= EMERGENCY_OBJ_COUNT)
|
|
goto failed;
|
|
}
|
|
|
|
emergency_used |= (bitmask_type)1 << which;
|
|
ret = &emergency_buffer[which][0];
|
|
|
|
failed:;
|
|
|
|
if (!ret)
|
|
std::terminate ();
|
|
}
|
|
|
|
// We have an uncaught exception as soon as we allocate memory. This
|
|
// yields uncaught_exception() true during the copy-constructor that
|
|
// initializes the exception object. See Issue 475.
|
|
__cxa_eh_globals *globals = __cxa_get_globals ();
|
|
globals->uncaughtExceptions += 1;
|
|
|
|
memset (ret, 0, sizeof (__cxa_exception));
|
|
|
|
return (void *)((char *)ret + sizeof (__cxa_exception));
|
|
}
|
|
|
|
|
|
extern "C" void
|
|
__cxxabiv1::__cxa_free_exception(void *vptr) throw()
|
|
{
|
|
char *ptr = (char *) vptr;
|
|
if (ptr >= &emergency_buffer[0][0]
|
|
&& ptr < &emergency_buffer[0][0] + sizeof (emergency_buffer))
|
|
{
|
|
const unsigned int which
|
|
= (unsigned)(ptr - &emergency_buffer[0][0]) / EMERGENCY_OBJ_SIZE;
|
|
|
|
__gnu_cxx::__scoped_lock sentry(emergency_mutex);
|
|
emergency_used &= ~((bitmask_type)1 << which);
|
|
}
|
|
else
|
|
free (ptr - sizeof (__cxa_exception));
|
|
}
|