Whole document tree
    

Whole document tree

unwind-cxx.h Source File
Main Page   Namespace List   Class Hierarchy   Alphabetical List   Compound List   File List   Namespace Members   Compound Members   File Members  

unwind-cxx.h

Go to the documentation of this file.
00001 // -*- C++ -*- Exception handling and frame unwind runtime interface routines.
00002 // Copyright (C) 2001 Free Software Foundation, Inc.
00003 //
00004 // This file is part of GNU CC.
00005 //
00006 // GNU CC is free software; you can redistribute it and/or modify
00007 // it under the terms of the GNU General Public License as published by
00008 // the Free Software Foundation; either version 2, or (at your option)
00009 // any later version.
00010 //
00011 // GNU CC is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 //
00016 // You should have received a copy of the GNU General Public License
00017 // along with GNU CC; see the file COPYING.  If not, write to
00018 // the Free Software Foundation, 59 Temple Place - Suite 330,
00019 // Boston, MA 02111-1307, USA.
00020 
00021 // This is derived from the C++ ABI for IA-64.  Where we diverge
00022 // for cross-architecture compatibility are noted with "@@@".
00023 
00024 #ifndef __UNWIND_CXX_H
00025 #define __UNWIND_CXX_H 1
00026 
00027 // Level 2: C++ ABI
00028 
00029 #include <typeinfo>
00030 #include <exception>
00031 #include <cstddef>
00032 #include "unwind.h"
00033 
00034 namespace __cxxabiv1
00035 {
00036 
00037 // A C++ exception object consists of a header, which is a wrapper around
00038 // an unwind object header with additional C++ specific information,
00039 // followed by the exception object itself.
00040 
00041 struct __cxa_exception
00042 { 
00043   // Manage the exception object itself.
00044   std::type_info *exceptionType;
00045   void (*exceptionDestructor)(void *); 
00046 
00047   // The C++ standard has entertaining rules wrt calling set_terminate
00048   // and set_unexpected in the middle of the exception cleanup process.
00049   std::unexpected_handler unexpectedHandler;
00050   std::terminate_handler terminateHandler;
00051 
00052   // The caught exception stack threads through here.
00053   __cxa_exception *nextException;
00054 
00055   // How many nested handlers have caught this exception.  A negated
00056   // value is a signal that this object has been rethrown.
00057   int handlerCount;
00058 
00059   // Cache parsed handler data from the personality routine Phase 1
00060   // for Phase 2 and __cxa_call_unexpected.
00061   int handlerSwitchValue;
00062   const unsigned char *actionRecord;
00063   const unsigned char *languageSpecificData;
00064   void *catchTemp;
00065   void *adjustedPtr;
00066 
00067   // The generic exception header.  Must be last.
00068   _Unwind_Exception unwindHeader;
00069 };
00070 
00071 // Each thread in a C++ program has access to a __cxa_eh_globals object.
00072 struct __cxa_eh_globals
00073 {
00074   __cxa_exception *caughtExceptions;
00075   unsigned int uncaughtExceptions;
00076 };
00077 
00078 
00079 // The __cxa_eh_globals for the current thread can be obtained by using
00080 // either of the following functions.  The "fast" version assumes at least
00081 // one prior call of __cxa_get_globals has been made from the current
00082 // thread, so no initialization is necessary.
00083 extern "C" __cxa_eh_globals *__cxa_get_globals () throw();
00084 extern "C" __cxa_eh_globals *__cxa_get_globals_fast () throw();
00085 
00086 // Allocate memory for the exception plus the thown object.
00087 extern "C" void *__cxa_allocate_exception(std::size_t thrown_size) throw();
00088 
00089 // Free the space allocated for the exception.
00090 extern "C" void __cxa_free_exception(void *thrown_exception) throw();
00091 
00092 // Throw the exception.
00093 extern "C" void __cxa_throw (void *thrown_exception,
00094                  std::type_info *tinfo,
00095                  void (*dest) (void *))
00096      __attribute__((noreturn));
00097 
00098 // Used to implement exception handlers.
00099 extern "C" void *__cxa_begin_catch (_Unwind_Exception *) throw();
00100 extern "C" void __cxa_end_catch ();
00101 extern "C" void __cxa_rethrow () __attribute__((noreturn));
00102 
00103 // These facilitate code generation for recurring situations.
00104 extern "C" void __cxa_bad_cast ();
00105 extern "C" void __cxa_bad_typeid ();
00106 
00107 // @@@ These are not directly specified by the IA-64 C++ ABI.
00108 
00109 // Handles re-checking the exception specification if unexpectedHandler
00110 // throws, and if bad_exception needs to be thrown.  Called from the
00111 // compiler.
00112 extern "C" void __cxa_call_unexpected (_Unwind_Exception *)
00113      __attribute__((noreturn));
00114 
00115 // Invokes given handler, dying appropriately if the user handler was
00116 // so inconsiderate as to return.
00117 extern void __terminate(std::terminate_handler) __attribute__((noreturn));
00118 extern void __unexpected(std::unexpected_handler) __attribute__((noreturn));
00119 
00120 // The current installed user handlers.
00121 extern std::terminate_handler __terminate_handler;
00122 extern std::unexpected_handler __unexpected_handler;
00123 
00124 // These are explicitly GNU C++ specific.
00125 
00126 // This is the exception class we report -- "GNUCC++\0".
00127 const _Unwind_Exception_Class __gxx_exception_class
00128 = ((((((((_Unwind_Exception_Class) 'G' 
00129      << 8 | (_Unwind_Exception_Class) 'N')
00130     << 8 | (_Unwind_Exception_Class) 'U')
00131        << 8 | (_Unwind_Exception_Class) 'C')
00132       << 8 | (_Unwind_Exception_Class) 'C')
00133      << 8 | (_Unwind_Exception_Class) '+')
00134     << 8 | (_Unwind_Exception_Class) '+')
00135    << 8 | (_Unwind_Exception_Class) '\0');
00136 
00137 // GNU C++ personality routine, Version 0.
00138 extern "C" _Unwind_Reason_Code __gxx_personality_v0
00139      (int, _Unwind_Action, _Unwind_Exception_Class,
00140       struct _Unwind_Exception *, struct _Unwind_Context *);
00141 
00142 // GNU C++ sjlj personality routine, Version 0.
00143 extern "C" _Unwind_Reason_Code __gxx_personality_sj0
00144      (int, _Unwind_Action, _Unwind_Exception_Class,
00145       struct _Unwind_Exception *, struct _Unwind_Context *);
00146 
00147 // Acquire the C++ exception header from the C++ object.
00148 static inline __cxa_exception *
00149 __get_exception_header_from_obj (void *ptr)
00150 {
00151   return reinterpret_cast<__cxa_exception *>(ptr) - 1;
00152 }
00153 
00154 // Acquire the C++ exception header from the generic exception header.
00155 static inline __cxa_exception *
00156 __get_exception_header_from_ue (_Unwind_Exception *exc)
00157 {
00158   return reinterpret_cast<__cxa_exception *>(exc + 1) - 1;
00159 }
00160 
00161 } /* namespace __cxxabiv1 */
00162 
00163 #endif // __UNWIND_CXX_H

Generated on Mon Apr 8 03:11:47 2002 for libstdc++-v3 Source by doxygen1.2.15