1//===----------------------------------------------------------------------===// 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 32typedef 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 48typedef 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 56typedef 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 64typedef _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 73extern "C" { 74#endif 75 76extern uintptr_t _Unwind_GetRegionStart(struct _Unwind_Context *context); 77extern uintptr_t 78 _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context); 79#ifdef __USING_SJLJ_EXCEPTIONS__ 80extern _Unwind_Reason_Code 81 _Unwind_SjLj_ForcedUnwind(_Unwind_Exception *exception_object, 82 _Unwind_Stop_Fn stop, void *stop_parameter); 83#else 84extern _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__ 90typedef struct _Unwind_FunctionContext *_Unwind_FunctionContext_t; 91extern void _Unwind_SjLj_Register(_Unwind_FunctionContext_t fc); 92extern void _Unwind_SjLj_Unregister(_Unwind_FunctionContext_t fc); 93#endif 94 95// 96// The following are semi-supported extensions to the C++ ABI 97// 98 99// 100// called by __cxa_rethrow(). 101// 102#ifdef __USING_SJLJ_EXCEPTIONS__ 103extern _Unwind_Reason_Code 104 _Unwind_SjLj_Resume_or_Rethrow(_Unwind_Exception *exception_object); 105#else 106extern _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. 113typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn)(struct _Unwind_Context *, 114 void *); 115extern _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. 120extern 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. 129extern 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. 139extern void __register_frame(const void *fde); 140extern 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. 147struct dwarf_eh_bases { 148 uintptr_t tbase; 149 uintptr_t dbase; 150 uintptr_t func; 151}; 152extern 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. 160extern 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. 164extern uintptr_t _Unwind_GetDataRelBase(struct _Unwind_Context *context) 165 LIBUNWIND_UNAVAIL; 166extern 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. 172extern void __register_frame_info_bases(const void *fde, void *ob, void *tb, 173 void *db) LIBUNWIND_UNAVAIL; 174extern void __register_frame_info(const void *fde, void *ob) 175 LIBUNWIND_UNAVAIL; 176extern void __register_frame_info_table_bases(const void *fde, void *ob, 177 void *tb, void *db) 178 LIBUNWIND_UNAVAIL; 179extern void __register_frame_info_table(const void *fde, void *ob) 180 LIBUNWIND_UNAVAIL; 181extern void __register_frame_table(const void *fde) 182 LIBUNWIND_UNAVAIL; 183extern void *__deregister_frame_info(const void *fde) 184 LIBUNWIND_UNAVAIL; 185extern void *__deregister_frame_info_bases(const void *fde) 186 LIBUNWIND_UNAVAIL; 187 188#if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__) 189#ifndef _WIN32 190typedef struct _EXCEPTION_RECORD EXCEPTION_RECORD; 191typedef struct _CONTEXT CONTEXT; 192typedef struct _DISPATCHER_CONTEXT DISPATCHER_CONTEXT; 193#elif !defined(__MINGW32__) && VER_PRODUCTBUILD < 8000 194typedef struct _DISPATCHER_CONTEXT DISPATCHER_CONTEXT; 195#endif 196// This is the common wrapper for GCC-style personality functions with SEH. 197extern 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