| 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 | |
