1 // -*- C++ -*- ARM specific Exception handling support routines.
2 // Copyright (C) 2004, 2005 Free Software Foundation, Inc.
4 // This file is part of GCC.
6 // GCC 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 // GCC 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 GCC; see the file COPYING. If not, write to
18 // the Free Software Foundation, 51 Franklin Street, Fifth Floor,
19 // Boston, MA 02110-1301, 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.
31 #include "unwind-cxx.h"
33 #ifdef __ARM_EABI_UNWINDER__
35 using namespace __cxxabiv1
;
38 // Given the thrown type THROW_TYPE, pointer to a variable containing a
39 // pointer to the exception object THROWN_PTR_P and a type CATCH_TYPE to
40 // compare against, return whether or not there is a match and if so,
41 // update *THROWN_PTR_P.
43 extern "C" __cxa_type_match_result
44 __cxa_type_match(_Unwind_Exception
* ue_header
,
45 const std::type_info
* catch_type
,
46 bool is_reference
__attribute__((__unused__
)),
49 bool foreign_exception
= !__is_gxx_exception_class(ue_header
->exception_class
);
50 __cxa_exception
* xh
= __get_exception_header_from_ue(ue_header
);
51 const std::type_info
* throw_type
;
53 // XXX What to do with forced unwind?
54 if (foreign_exception
)
55 throw_type
= &typeid(abi::__foreign_exception
);
57 throw_type
= xh
->exceptionType
;
59 void* thrown_ptr
= *thrown_ptr_p
;
61 // Pointer types need to adjust the actual pointer, not
62 // the pointer to pointer that is the exception object.
63 // This also has the effect of passing pointer types
64 // "by value" through the __cxa_begin_catch return value.
65 if (throw_type
->__is_pointer_p())
66 thrown_ptr
= *(void**) thrown_ptr
;
68 if (catch_type
->__do_catch(throw_type
, &thrown_ptr
, 1))
70 *thrown_ptr_p
= thrown_ptr
;
72 if (typeid(*catch_type
) == typeid (typeid(void*)))
74 const __pointer_type_info
*catch_pointer_type
=
75 static_cast<const __pointer_type_info
*> (catch_type
);
76 const __pointer_type_info
*throw_pointer_type
=
77 static_cast<const __pointer_type_info
*> (throw_type
);
79 if (typeid (*catch_pointer_type
->__pointee
) != typeid (void)
80 && (*catch_pointer_type
->__pointee
!=
81 *throw_pointer_type
->__pointee
))
82 return ctm_succeeded_with_ptr_to_base
;
91 // ABI defined routine called at the start of a cleanup handler.
93 __cxa_begin_cleanup(_Unwind_Exception
* ue_header
)
95 __cxa_eh_globals
*globals
= __cxa_get_globals();
96 __cxa_exception
*header
= __get_exception_header_from_ue(ue_header
);
97 bool native
= __is_gxx_exception_class(header
->unwindHeader
.exception_class
);
102 header
->propagationCount
++;
103 // Add it to the chain if this is the first time we've seen this
105 if (header
->propagationCount
== 1)
107 header
->nextPropagatingException
= globals
->propagatingExceptions
;
108 globals
->propagatingExceptions
= header
;
113 // Remember the exception object, so end_cleanup can return it.
114 // These cannot be stacked, so we must abort if we already have
115 // a propagating exception.
116 if (globals
->propagatingExceptions
)
118 globals
->propagatingExceptions
= header
;
124 // Do the work for __cxa_end_cleanup. Returns the currently propagating
126 extern "C" _Unwind_Exception
*
127 __gnu_end_cleanup(void)
129 __cxa_exception
*header
;
130 __cxa_eh_globals
*globals
= __cxa_get_globals();
132 header
= globals
->propagatingExceptions
;
134 // Check something hasn't gone horribly wrong.
138 if (__is_gxx_exception_class(header
->unwindHeader
.exception_class
))
140 header
->propagationCount
--;
141 if (header
->propagationCount
== 0)
143 // Remove exception from chain.
144 globals
->propagatingExceptions
= header
->nextPropagatingException
;
145 header
->nextPropagatingException
= NULL
;
149 globals
->propagatingExceptions
= NULL
;
151 return &header
->unwindHeader
;
154 // Assembly wrapper to call __gnu_end_cleanup without clobbering r1-r3.
155 // Also push r4 to preserve stack alignment.
157 asm (".global __cxa_end_cleanup\n"
158 " .type __cxa_end_cleanup, \"function\"\n"
160 "__cxa_end_cleanup:\n"
161 " push\t{r1, r2, r3, r4}\n"
162 " bl\t__gnu_end_cleanup\n"
163 " pop\t{r1, r2, r3, r4}\n"
164 " bl\t_Unwind_Resume @ Never returns\n");
166 asm (".global __cxa_end_cleanup\n"
167 " .type __cxa_end_cleanup, \"function\"\n"
168 "__cxa_end_cleanup:\n"
169 " stmfd\tsp!, {r1, r2, r3, r4}\n"
170 " bl\t__gnu_end_cleanup\n"
171 " ldmfd\tsp!, {r1, r2, r3, r4}\n"
172 " bl\t_Unwind_Resume @ Never returns\n");