1 //===------------------------------- unwind.h -----------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 // 8 // C++ ABI Level 1 ABI documented at: 9 // https://itanium-cxx-abi.github.io/cxx-abi/abi-eh.html 10 // 11 //===----------------------------------------------------------------------===// 12 13 #ifndef __UNWIND_H__ 14 #define __UNWIND_H__ 15 16 #include <__libunwind_config.h> 17 18 #include <stdint.h> 19 #include <stddef.h> 20 21 #if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__) && defined(_WIN32) 22 #include <windows.h> 23 #include <ntverp.h> 24 #endif 25 26 #if defined(__APPLE__) 27 #define LIBUNWIND_UNAVAIL __attribute__ (( unavailable )) 28 #else 29 #define LIBUNWIND_UNAVAIL 30 #endif 31 32 typedef enum { 33 _URC_NO_REASON = 0, 34 _URC_OK = 0, 35 _URC_FOREIGN_EXCEPTION_CAUGHT = 1, 36 _URC_FATAL_PHASE2_ERROR = 2, 37 _URC_FATAL_PHASE1_ERROR = 3, 38 _URC_NORMAL_STOP = 4, 39 _URC_END_OF_STACK = 5, 40 _URC_HANDLER_FOUND = 6, 41 _URC_INSTALL_CONTEXT = 7, 42 _URC_CONTINUE_UNWIND = 8, 43 #if defined(_LIBUNWIND_ARM_EHABI) 44 _URC_FAILURE = 9 45 #endif 46 } _Unwind_Reason_Code; 47 48 typedef enum { 49 _UA_SEARCH_PHASE = 1, 50 _UA_CLEANUP_PHASE = 2, 51 _UA_HANDLER_FRAME = 4, 52 _UA_FORCE_UNWIND = 8, 53 _UA_END_OF_STACK = 16 // gcc extension to C++ ABI 54 } _Unwind_Action; 55 56 typedef struct _Unwind_Context _Unwind_Context; // opaque 57 58 #if defined(_LIBUNWIND_ARM_EHABI) 59 #include "unwind_arm_ehabi.h" 60 #else 61 #include "unwind_itanium.h" 62 #endif 63 64 typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn) 65 (int version, 66 _Unwind_Action actions, 67 _Unwind_Exception_Class exceptionClass, 68 _Unwind_Exception* exceptionObject, 69 struct _Unwind_Context* context, 70 void* stop_parameter); 71 72 #ifdef __cplusplus 73 extern "C" { 74 #endif 75 76 extern uintptr_t _Unwind_GetRegionStart(struct _Unwind_Context *context); 77 extern uintptr_t 78 _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context); 79 #ifdef __USING_SJLJ_EXCEPTIONS__ 80 extern _Unwind_Reason_Code 81 _Unwind_SjLj_ForcedUnwind(_Unwind_Exception *exception_object, 82 _Unwind_Stop_Fn stop, void *stop_parameter); 83 #else 84 extern _Unwind_Reason_Code 85 _Unwind_ForcedUnwind(_Unwind_Exception *exception_object, 86 _Unwind_Stop_Fn stop, void *stop_parameter); 87 #endif 88 89 #ifdef __USING_SJLJ_EXCEPTIONS__ 90 typedef struct _Unwind_FunctionContext *_Unwind_FunctionContext_t; 91 extern void _Unwind_SjLj_Register(_Unwind_FunctionContext_t fc); 92 extern void _Unwind_SjLj_Unregister(_Unwind_FunctionContext_t fc); 93 #endif 94 95 // 96 // The following are semi-suppoted extensions to the C++ ABI 97 // 98 99 // 100 // called by __cxa_rethrow(). 101 // 102 #ifdef __USING_SJLJ_EXCEPTIONS__ 103 extern _Unwind_Reason_Code 104 _Unwind_SjLj_Resume_or_Rethrow(_Unwind_Exception *exception_object); 105 #else 106 extern _Unwind_Reason_Code 107 _Unwind_Resume_or_Rethrow(_Unwind_Exception *exception_object); 108 #endif 109 110 // _Unwind_Backtrace() is a gcc extension that walks the stack and calls the 111 // _Unwind_Trace_Fn once per frame until it reaches the bottom of the stack 112 // or the _Unwind_Trace_Fn function returns something other than _URC_NO_REASON. 113 typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn)(struct _Unwind_Context *, 114 void *); 115 extern _Unwind_Reason_Code _Unwind_Backtrace(_Unwind_Trace_Fn, void *); 116 117 // _Unwind_GetCFA is a gcc extension that can be called from within a 118 // personality handler to get the CFA (stack pointer before call) of 119 // current frame. 120 extern uintptr_t _Unwind_GetCFA(struct _Unwind_Context *); 121 122 123 // _Unwind_GetIPInfo is a gcc extension that can be called from within a 124 // personality handler. Similar to _Unwind_GetIP() but also returns in 125 // *ipBefore a non-zero value if the instruction pointer is at or before the 126 // instruction causing the unwind. Normally, in a function call, the IP returned 127 // is the return address which is after the call instruction and may be past the 128 // end of the function containing the call instruction. 129 extern uintptr_t _Unwind_GetIPInfo(struct _Unwind_Context *context, 130 int *ipBefore); 131 132 133 // __register_frame() is used with dynamically generated code to register the 134 // FDE for a generated (JIT) code. The FDE must use pc-rel addressing to point 135 // to its function and optional LSDA. 136 // __register_frame() has existed in all versions of Mac OS X, but in 10.4 and 137 // 10.5 it was buggy and did not actually register the FDE with the unwinder. 138 // In 10.6 and later it does register properly. 139 extern void __register_frame(const void *fde); 140 extern void __deregister_frame(const void *fde); 141 142 // _Unwind_Find_FDE() will locate the FDE if the pc is in some function that has 143 // an associated FDE. Note, Mac OS X 10.6 and later, introduces "compact unwind 144 // info" which the runtime uses in preference to DWARF unwind info. This 145 // function will only work if the target function has an FDE but no compact 146 // unwind info. 147 struct dwarf_eh_bases { 148 uintptr_t tbase; 149 uintptr_t dbase; 150 uintptr_t func; 151 }; 152 extern const void *_Unwind_Find_FDE(const void *pc, struct dwarf_eh_bases *); 153 154 155 // This function attempts to find the start (address of first instruction) of 156 // a function given an address inside the function. It only works if the 157 // function has an FDE (DWARF unwind info). 158 // This function is unimplemented on Mac OS X 10.6 and later. Instead, use 159 // _Unwind_Find_FDE() and look at the dwarf_eh_bases.func result. 160 extern void *_Unwind_FindEnclosingFunction(void *pc); 161 162 // Mac OS X does not support text-rel and data-rel addressing so these functions 163 // are unimplemented 164 extern uintptr_t _Unwind_GetDataRelBase(struct _Unwind_Context *context) 165 LIBUNWIND_UNAVAIL; 166 extern uintptr_t _Unwind_GetTextRelBase(struct _Unwind_Context *context) 167 LIBUNWIND_UNAVAIL; 168 169 // Mac OS X 10.4 and 10.5 had implementations of these functions in 170 // libgcc_s.dylib, but they never worked. 171 /// These functions are no longer available on Mac OS X. 172 extern void __register_frame_info_bases(const void *fde, void *ob, void *tb, 173 void *db) LIBUNWIND_UNAVAIL; 174 extern void __register_frame_info(const void *fde, void *ob) 175 LIBUNWIND_UNAVAIL; 176 extern void __register_frame_info_table_bases(const void *fde, void *ob, 177 void *tb, void *db) 178 LIBUNWIND_UNAVAIL; 179 extern void __register_frame_info_table(const void *fde, void *ob) 180 LIBUNWIND_UNAVAIL; 181 extern void __register_frame_table(const void *fde) 182 LIBUNWIND_UNAVAIL; 183 extern void *__deregister_frame_info(const void *fde) 184 LIBUNWIND_UNAVAIL; 185 extern void *__deregister_frame_info_bases(const void *fde) 186 LIBUNWIND_UNAVAIL; 187 188 #if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__) 189 #ifndef _WIN32 190 typedef struct _EXCEPTION_RECORD EXCEPTION_RECORD; 191 typedef struct _CONTEXT CONTEXT; 192 typedef struct _DISPATCHER_CONTEXT DISPATCHER_CONTEXT; 193 #elif !defined(__MINGW32__) && VER_PRODUCTBUILD < 8000 194 typedef struct _DISPATCHER_CONTEXT DISPATCHER_CONTEXT; 195 #endif 196 // This is the common wrapper for GCC-style personality functions with SEH. 197 extern EXCEPTION_DISPOSITION _GCC_specific_handler(EXCEPTION_RECORD *exc, 198 void *frame, CONTEXT *ctx, 199 DISPATCHER_CONTEXT *disp, 200 _Unwind_Personality_Fn pers); 201 #endif 202 203 #ifdef __cplusplus 204 } 205 #endif 206 207 #endif // __UNWIND_H__ 208