1 // -*- C++ -*- Allocate exception objects.
2 // Copyright (C) 2001 Free Software Foundation, Inc.
4 // This file is part of GNU CC.
6 // GNU CC is free software; you can redistribute it and/or modify
7 // it under the terms of the GNU General Public License as published by
8 // the Free Software Foundation; either version 2, or (at your option)
11 // GNU CC is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
16 // You should have received a copy of the GNU General Public License
17 // along with GNU CC; see the file COPYING. If not, write to
18 // the Free Software Foundation, 59 Temple Place - Suite 330,
19 // Boston, MA 02111-1307, USA.
21 // As a special exception, you may use this file as part of a free software
22 // library without restriction. Specifically, if other files instantiate
23 // templates or use macros or inline functions from this file, or you compile
24 // this file and link it with other files to produce an executable, this
25 // file does not by itself cause the resulting executable to be covered by
26 // the GNU General Public License. This exception does not however
27 // invalidate any other reasons why the executable file might be covered by
28 // the GNU General Public License.
30 // This is derived from the C++ ABI for IA-64. Where we diverge
31 // for cross-architecture compatibility are noted with "@@@".
37 #include "unwind-cxx.h"
40 using namespace __cxxabiv1;
43 // ??? How to control these parameters.
45 // Guess from the size of basic types how large a buffer is reasonable.
46 // Note that the basic c++ exception header has 13 pointers and 2 ints,
47 // so on a system with PSImode pointers we're talking about 56 bytes
51 # define EMERGENCY_OBJ_SIZE 128
52 # define EMERGENCY_OBJ_COUNT 16
53 #elif LONG_MAX == 2147483647
54 # define EMERGENCY_OBJ_SIZE 512
55 # define EMERGENCY_OBJ_COUNT 32
57 # define EMERGENCY_OBJ_SIZE 1024
58 # define EMERGENCY_OBJ_COUNT 64
62 # undef EMERGENCY_OBJ_COUNT
63 # define EMERGENCY_OBJ_COUNT 4
66 #if INT_MAX == 32767 || EMERGENCY_OBJ_COUNT <= 32
67 typedef unsigned int bitmask_type;
69 typedef unsigned long bitmask_type;
73 typedef char one_buffer[EMERGENCY_OBJ_SIZE] __attribute__((aligned));
74 static one_buffer emergency_buffer[EMERGENCY_OBJ_COUNT];
75 static bitmask_type emergency_used;
79 #ifdef __GTHREAD_MUTEX_INIT
80 static __gthread_mutex_t emergency_mutex =__GTHREAD_MUTEX_INIT;
82 static __gthread_mutex_t emergency_mutex;
85 #ifdef __GTHREAD_MUTEX_INIT_FUNCTION
87 emergency_mutex_init ()
89 __GTHREAD_MUTEX_INIT_FUNCTION (&emergency_mutex);
96 __cxa_allocate_exception(std::size_t thrown_size)
100 thrown_size += sizeof (__cxa_exception);
101 ret = std::malloc (thrown_size);
106 #ifdef __GTHREAD_MUTEX_INIT_FUNCTION
107 static __gthread_once_t once = __GTHREAD_ONCE_INIT;
108 __gthread_once (&once, emergency_mutex_init);
110 __gthread_mutex_lock (&emergency_mutex);
113 bitmask_type used = emergency_used;
114 unsigned int which = 0;
116 if (thrown_size > EMERGENCY_OBJ_SIZE)
121 if (++which >= EMERGENCY_OBJ_COUNT)
125 emergency_used |= (bitmask_type)1 << which;
126 ret = &emergency_buffer[which][0];
130 __gthread_mutex_unlock (&emergency_mutex);
136 std::memset (ret, 0, sizeof (__cxa_exception));
138 return (void *)((char *)ret + sizeof (__cxa_exception));
143 __cxa_free_exception(void *vptr)
145 char *ptr = (char *) vptr;
146 if (ptr >= &emergency_buffer[0][0]
147 && ptr < &emergency_buffer[0][0] + sizeof (emergency_buffer))
150 = (unsigned)(ptr - &emergency_buffer[0][0]) / EMERGENCY_OBJ_SIZE;
153 __gthread_mutex_lock (&emergency_mutex);
154 emergency_used &= ~((bitmask_type)1 << which);
155 __gthread_mutex_unlock (&emergency_mutex);
157 emergency_used &= ~((bitmask_type)1 << which);
161 std::free (ptr - sizeof (__cxa_exception));