1 /* Exception handling and frame unwind runtime interface routines. 2 Copyright (C) 2001, 2003, 2004, 2006 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify it 7 under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 GCC is distributed in the hope that it will be useful, but WITHOUT 12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 13 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public 14 License for more details. 15 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 the Free 18 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 19 02110-1301, USA. */ 20 21 /* As a special exception, if you include this header file into source 22 files compiled by GCC, this header file does not by itself cause 23 the resulting executable to be covered by the GNU General Public 24 License. This exception does not however invalidate any other 25 reasons why the executable file might be covered by the GNU General 26 Public License. */ 27 28 /* This is derived from the C++ ABI for IA-64. Where we diverge 29 for cross-architecture compatibility are noted with "@@@". */ 30 31 #ifndef _UNWIND_H 32 #define _UNWIND_H 33 34 #ifndef HIDE_EXPORTS 35 #pragma GCC visibility push(default) 36 #endif 37 38 #ifdef __cplusplus 39 extern "C" { 40 #endif 41 42 /* Level 1: Base ABI */ 43 44 /* @@@ The IA-64 ABI uses uint64 throughout. Most places this is 45 inefficient for 32-bit and smaller machines. */ 46 typedef unsigned _Unwind_Word __attribute__((__mode__(__word__))); 47 typedef signed _Unwind_Sword __attribute__((__mode__(__word__))); 48 #if defined(__ia64__) && defined(__hpux__) 49 typedef unsigned _Unwind_Ptr __attribute__((__mode__(__word__))); 50 #else 51 typedef unsigned _Unwind_Ptr __attribute__((__mode__(__pointer__))); 52 #endif 53 typedef unsigned _Unwind_Internal_Ptr __attribute__((__mode__(__pointer__))); 54 55 /* @@@ The IA-64 ABI uses a 64-bit word to identify the producer and 56 consumer of an exception. We'll go along with this for now even on 57 32-bit machines. We'll need to provide some other option for 58 16-bit machines and for machines with > 8 bits per byte. */ 59 typedef unsigned _Unwind_Exception_Class __attribute__((__mode__(__DI__))); 60 61 /* The unwind interface uses reason codes in several contexts to 62 identify the reasons for failures or other actions. */ 63 typedef enum 64 { 65 _URC_NO_REASON = 0, 66 _URC_FOREIGN_EXCEPTION_CAUGHT = 1, 67 _URC_FATAL_PHASE2_ERROR = 2, 68 _URC_FATAL_PHASE1_ERROR = 3, 69 _URC_NORMAL_STOP = 4, 70 _URC_END_OF_STACK = 5, 71 _URC_HANDLER_FOUND = 6, 72 _URC_INSTALL_CONTEXT = 7, 73 _URC_CONTINUE_UNWIND = 8 74 } _Unwind_Reason_Code; 75 76 77 /* The unwind interface uses a pointer to an exception header object 78 as its representation of an exception being thrown. In general, the 79 full representation of an exception object is language- and 80 implementation-specific, but it will be prefixed by a header 81 understood by the unwind interface. */ 82 83 struct _Unwind_Exception; 84 85 typedef void (*_Unwind_Exception_Cleanup_Fn) (_Unwind_Reason_Code, 86 struct _Unwind_Exception *); 87 88 struct _Unwind_Exception 89 { 90 _Unwind_Exception_Class exception_class; 91 _Unwind_Exception_Cleanup_Fn exception_cleanup; 92 _Unwind_Word private_1; 93 _Unwind_Word private_2; 94 95 /* @@@ The IA-64 ABI says that this structure must be double-word aligned. 96 Taking that literally does not make much sense generically. Instead we 97 provide the maximum alignment required by any type for the machine. */ 98 } __attribute__((__aligned__)); 99 100 101 /* The ACTIONS argument to the personality routine is a bitwise OR of one 102 or more of the following constants. */ 103 typedef int _Unwind_Action; 104 105 #define _UA_SEARCH_PHASE 1 106 #define _UA_CLEANUP_PHASE 2 107 #define _UA_HANDLER_FRAME 4 108 #define _UA_FORCE_UNWIND 8 109 #define _UA_END_OF_STACK 16 110 111 /* This is an opaque type used to refer to a system-specific data 112 structure used by the system unwinder. This context is created and 113 destroyed by the system, and passed to the personality routine 114 during unwinding. */ 115 struct _Unwind_Context; 116 117 /* Raise an exception, passing along the given exception object. */ 118 extern _Unwind_Reason_Code _Unwind_RaiseException (struct _Unwind_Exception *); 119 120 /* Raise an exception for forced unwinding. */ 121 122 typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn) 123 (int, _Unwind_Action, _Unwind_Exception_Class, 124 struct _Unwind_Exception *, struct _Unwind_Context *, void *); 125 126 extern _Unwind_Reason_Code _Unwind_ForcedUnwind (struct _Unwind_Exception *, 127 _Unwind_Stop_Fn, 128 void *); 129 130 /* Helper to invoke the exception_cleanup routine. */ 131 extern void _Unwind_DeleteException (struct _Unwind_Exception *); 132 133 /* Resume propagation of an existing exception. This is used after 134 e.g. executing cleanup code, and not to implement rethrowing. */ 135 extern void _Unwind_Resume (struct _Unwind_Exception *); 136 137 /* @@@ Resume propagation of an FORCE_UNWIND exception, or to rethrow 138 a normal exception that was handled. */ 139 extern _Unwind_Reason_Code _Unwind_Resume_or_Rethrow (struct _Unwind_Exception *); 140 141 /* @@@ Use unwind data to perform a stack backtrace. The trace callback 142 is called for every stack frame in the call chain, but no cleanup 143 actions are performed. */ 144 typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn) 145 (struct _Unwind_Context *, void *); 146 147 extern _Unwind_Reason_Code _Unwind_Backtrace (_Unwind_Trace_Fn, void *); 148 149 /* These functions are used for communicating information about the unwind 150 context (i.e. the unwind descriptors and the user register state) between 151 the unwind library and the personality routine and landing pad. Only 152 selected registers maybe manipulated. */ 153 154 extern _Unwind_Word _Unwind_GetGR (struct _Unwind_Context *, int); 155 extern void _Unwind_SetGR (struct _Unwind_Context *, int, _Unwind_Word); 156 157 extern _Unwind_Ptr _Unwind_GetIP (struct _Unwind_Context *); 158 extern _Unwind_Ptr _Unwind_GetIPInfo (struct _Unwind_Context *, int *); 159 extern void _Unwind_SetIP (struct _Unwind_Context *, _Unwind_Ptr); 160 161 /* @@@ Retrieve the CFA of the given context. */ 162 extern _Unwind_Word _Unwind_GetCFA (struct _Unwind_Context *); 163 164 extern void *_Unwind_GetLanguageSpecificData (struct _Unwind_Context *); 165 166 extern _Unwind_Ptr _Unwind_GetRegionStart (struct _Unwind_Context *); 167 168 169 /* The personality routine is the function in the C++ (or other language) 170 runtime library which serves as an interface between the system unwind 171 library and language-specific exception handling semantics. It is 172 specific to the code fragment described by an unwind info block, and 173 it is always referenced via the pointer in the unwind info block, and 174 hence it has no ABI-specified name. 175 176 Note that this implies that two different C++ implementations can 177 use different names, and have different contents in the language 178 specific data area. Moreover, that the language specific data 179 area contains no version info because name of the function invoked 180 provides more effective versioning by detecting at link time the 181 lack of code to handle the different data format. */ 182 183 typedef _Unwind_Reason_Code (*_Unwind_Personality_Fn) 184 (int, _Unwind_Action, _Unwind_Exception_Class, 185 struct _Unwind_Exception *, struct _Unwind_Context *); 186 187 /* @@@ The following alternate entry points are for setjmp/longjmp 188 based unwinding. */ 189 190 struct SjLj_Function_Context; 191 extern void _Unwind_SjLj_Register (struct SjLj_Function_Context *); 192 extern void _Unwind_SjLj_Unregister (struct SjLj_Function_Context *); 193 194 extern _Unwind_Reason_Code _Unwind_SjLj_RaiseException 195 (struct _Unwind_Exception *); 196 extern _Unwind_Reason_Code _Unwind_SjLj_ForcedUnwind 197 (struct _Unwind_Exception *, _Unwind_Stop_Fn, void *); 198 extern void _Unwind_SjLj_Resume (struct _Unwind_Exception *); 199 extern _Unwind_Reason_Code _Unwind_SjLj_Resume_or_Rethrow (struct _Unwind_Exception *); 200 201 /* @@@ The following provide access to the base addresses for text 202 and data-relative addressing in the LDSA. In order to stay link 203 compatible with the standard ABI for IA-64, we inline these. */ 204 205 #ifdef __ia64__ 206 #include <stdlib.h> 207 208 static inline _Unwind_Ptr 209 _Unwind_GetDataRelBase (struct _Unwind_Context *_C) 210 { 211 /* The GP is stored in R1. */ 212 return _Unwind_GetGR (_C, 1); 213 } 214 215 static inline _Unwind_Ptr 216 _Unwind_GetTextRelBase (struct _Unwind_Context *_C __attribute__ ((__unused__))) 217 { 218 abort (); 219 return 0; 220 } 221 222 /* @@@ Retrieve the Backing Store Pointer of the given context. */ 223 extern _Unwind_Word _Unwind_GetBSP (struct _Unwind_Context *); 224 #else 225 extern _Unwind_Ptr _Unwind_GetDataRelBase (struct _Unwind_Context *); 226 extern _Unwind_Ptr _Unwind_GetTextRelBase (struct _Unwind_Context *); 227 #endif 228 229 /* @@@ Given an address, return the entry point of the function that 230 contains it. */ 231 extern void * _Unwind_FindEnclosingFunction (void *pc); 232 233 #ifdef __cplusplus 234 } 235 #endif 236 237 #ifndef HIDE_EXPORTS 238 #pragma GCC visibility pop 239 #endif 240 241 #endif /* unwind.h */ 242
