1//===------------------------------- unwind.h -----------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is dual licensed under the MIT and the University of Illinois Open 6// Source Licenses. See LICENSE.TXT for details. 7// 8// 9// C++ ABI Level 1 ABI documented at: 10// http://mentorembedded.github.io/cxx-abi/abi-eh.html 11// 12//===----------------------------------------------------------------------===// 13 14#ifndef __UNWIND_H__ 15#define __UNWIND_H__ 16 17#include <stdint.h> 18#include <stddef.h> 19 20#if defined(__APPLE__) 21#define LIBUNWIND_UNAVAIL __attribute__ (( unavailable )) 22#else 23#define LIBUNWIND_UNAVAIL 24#endif 25 26// FIXME: This is also in cxxabi.h and libunwind.h, can we consolidate? 27#if !defined(__USING_SJLJ_EXCEPTIONS__) && defined(__arm__) && \ 28 !defined(__ARM_DWARF_EH__) && !defined(__APPLE__) 29#define LIBCXXABI_ARM_EHABI 1 30#else 31#define LIBCXXABI_ARM_EHABI 0 32#endif 33 34typedef enum { 35 _URC_NO_REASON = 0, 36 _URC_OK = 0, 37 _URC_FOREIGN_EXCEPTION_CAUGHT = 1, 38 _URC_FATAL_PHASE2_ERROR = 2, 39 _URC_FATAL_PHASE1_ERROR = 3, 40 _URC_NORMAL_STOP = 4, 41 _URC_END_OF_STACK = 5, 42 _URC_HANDLER_FOUND = 6, 43 _URC_INSTALL_CONTEXT = 7, 44 _URC_CONTINUE_UNWIND = 8, 45#if LIBCXXABI_ARM_EHABI 46 _URC_FAILURE = 9 47#endif 48} _Unwind_Reason_Code; 49 50typedef enum { 51 _UA_SEARCH_PHASE = 1, 52 _UA_CLEANUP_PHASE = 2, 53 _UA_HANDLER_FRAME = 4, 54 _UA_FORCE_UNWIND = 8, 55 _UA_END_OF_STACK = 16 // gcc extension to C++ ABI 56} _Unwind_Action; 57 58typedef struct _Unwind_Context _Unwind_Context; // opaque 59 60#if LIBCXXABI_ARM_EHABI 61typedef uint32_t _Unwind_State; 62 63static const _Unwind_State _US_VIRTUAL_UNWIND_FRAME = 0; 64static const _Unwind_State _US_UNWIND_FRAME_STARTING = 1; 65static const _Unwind_State _US_UNWIND_FRAME_RESUME = 2; 66 67typedef uint32_t _Unwind_EHT_Header; 68 69struct _Unwind_Control_Block; 70typedef struct _Unwind_Control_Block _Unwind_Control_Block; 71typedef struct _Unwind_Control_Block _Unwind_Exception; /* Alias */ 72 73struct _Unwind_Control_Block { 74 uint64_t exception_class; 75 void (*exception_cleanup)(_Unwind_Reason_Code, _Unwind_Control_Block*); 76 77 /* Unwinder cache, private fields for the unwinder's use */ 78 struct { 79 uint32_t reserved1; /* init reserved1 to 0, then don't touch */ 80 uint32_t reserved2; 81 uint32_t reserved3; 82 uint32_t reserved4; 83 uint32_t reserved5; 84 } unwinder_cache; 85 86 /* Propagation barrier cache (valid after phase 1): */ 87 struct { 88 uint32_t sp; 89 uint32_t bitpattern[5]; 90 } barrier_cache; 91 92 /* Cleanup cache (preserved over cleanup): */ 93 struct { 94 uint32_t bitpattern[4]; 95 } cleanup_cache; 96 97 /* Pr cache (for pr's benefit): */ 98 struct { 99 uint32_t fnstart; /* function start address */ 100 _Unwind_EHT_Header* ehtp; /* pointer to EHT entry header word */ 101 uint32_t additional; 102 uint32_t reserved1; 103 } pr_cache; 104 105 long long int :0; /* Enforce the 8-byte alignment */ 106}; 107 108typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn) 109 (_Unwind_State state, 110 _Unwind_Exception* exceptionObject, 111 struct _Unwind_Context* context); 112 113typedef _Unwind_Reason_Code (*__personality_routine) 114 (_Unwind_State state, 115 _Unwind_Exception* exceptionObject, 116 struct _Unwind_Context* context); 117#else 118struct _Unwind_Context; // opaque 119struct _Unwind_Exception; // forward declaration 120typedef struct _Unwind_Exception _Unwind_Exception; 121 122struct _Unwind_Exception { 123 uint64_t exception_class; 124 void (*exception_cleanup)(_Unwind_Reason_Code reason, 125 _Unwind_Exception *exc); 126 uintptr_t private_1; // non-zero means forced unwind 127 uintptr_t private_2; // holds sp that phase1 found for phase2 to use 128#if !__LP64__ 129 // The gcc implementation of _Unwind_Exception used attribute mode on the 130 // above fields which had the side effect of causing this whole struct to 131 // round up to 32 bytes in size. To be more explicit, we add pad fields 132 // added for binary compatibility. 133 uint32_t reserved[3]; 134#endif 135}; 136 137typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn) 138 (int version, 139 _Unwind_Action actions, 140 uint64_t exceptionClass, 141 _Unwind_Exception* exceptionObject, 142 struct _Unwind_Context* context, 143 void* stop_parameter ); 144 145typedef _Unwind_Reason_Code (*__personality_routine) 146 (int version, 147 _Unwind_Action actions, 148 uint64_t exceptionClass, 149 _Unwind_Exception* exceptionObject, 150 struct _Unwind_Context* context); 151#endif 152 153#ifdef __cplusplus 154extern "C" { 155#endif 156 157// 158// The following are the base functions documented by the C++ ABI 159// 160#if __USING_SJLJ_EXCEPTIONS__ 161extern _Unwind_Reason_Code 162 _Unwind_SjLj_RaiseException(_Unwind_Exception *exception_object); 163extern void _Unwind_SjLj_Resume(_Unwind_Exception *exception_object); 164#else 165extern _Unwind_Reason_Code 166 _Unwind_RaiseException(_Unwind_Exception *exception_object); 167extern void _Unwind_Resume(_Unwind_Exception *exception_object); 168#endif 169extern void _Unwind_DeleteException(_Unwind_Exception *exception_object); 170 171#if LIBCXXABI_ARM_EHABI 172typedef enum { 173 _UVRSC_CORE = 0, /* integer register */ 174 _UVRSC_VFP = 1, /* vfp */ 175 _UVRSC_WMMXD = 3, /* Intel WMMX data register */ 176 _UVRSC_WMMXC = 4 /* Intel WMMX control register */ 177} _Unwind_VRS_RegClass; 178 179typedef enum { 180 _UVRSD_UINT32 = 0, 181 _UVRSD_VFPX = 1, 182 _UVRSD_UINT64 = 3, 183 _UVRSD_FLOAT = 4, 184 _UVRSD_DOUBLE = 5 185} _Unwind_VRS_DataRepresentation; 186 187typedef enum { 188 _UVRSR_OK = 0, 189 _UVRSR_NOT_IMPLEMENTED = 1, 190 _UVRSR_FAILED = 2 191} _Unwind_VRS_Result; 192 193extern void _Unwind_Complete(_Unwind_Exception* exception_object); 194 195extern _Unwind_VRS_Result 196_Unwind_VRS_Get(_Unwind_Context *context, _Unwind_VRS_RegClass regclass, 197 uint32_t regno, _Unwind_VRS_DataRepresentation representation, 198 void *valuep); 199 200extern _Unwind_VRS_Result 201_Unwind_VRS_Set(_Unwind_Context *context, _Unwind_VRS_RegClass regclass, 202 uint32_t regno, _Unwind_VRS_DataRepresentation representation, 203 void *valuep); 204 205extern _Unwind_VRS_Result 206_Unwind_VRS_Pop(_Unwind_Context *context, _Unwind_VRS_RegClass regclass, 207 uint32_t discriminator, 208 _Unwind_VRS_DataRepresentation representation); 209 210static inline uintptr_t _Unwind_GetGR(struct _Unwind_Context* context, 211 int index) { 212 uintptr_t value = 0; 213 _Unwind_VRS_Get(context, _UVRSC_CORE, (uint32_t)index, _UVRSD_UINT32, &value); 214 return value; 215} 216 217static inline void _Unwind_SetGR(struct _Unwind_Context* context, int index, 218 uintptr_t new_value) { 219 _Unwind_VRS_Set(context, _UVRSC_CORE, (uint32_t)index, 220 _UVRSD_UINT32, &new_value); 221} 222 223static inline uintptr_t _Unwind_GetIP(struct _Unwind_Context* context) { 224 // remove the thumb-bit before returning 225 return (_Unwind_GetGR(context, 15) & (~(uintptr_t)0x1)); 226} 227 228static inline void _Unwind_SetIP(struct _Unwind_Context* context, 229 uintptr_t new_value) { 230 uintptr_t thumb_bit = _Unwind_GetGR(context, 15) & ((uintptr_t)0x1); 231 _Unwind_SetGR(context, 15, new_value | thumb_bit); 232} 233#else 234extern uintptr_t _Unwind_GetGR(struct _Unwind_Context *context, int index); 235extern void _Unwind_SetGR(struct _Unwind_Context *context, int index, 236 uintptr_t new_value); 237extern uintptr_t _Unwind_GetIP(struct _Unwind_Context *context); 238extern void _Unwind_SetIP(struct _Unwind_Context *, uintptr_t new_value); 239#endif 240 241extern uintptr_t _Unwind_GetRegionStart(struct _Unwind_Context *context); 242extern uintptr_t 243 _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context); 244#if __USING_SJLJ_EXCEPTIONS__ 245extern _Unwind_Reason_Code 246 _Unwind_SjLj_ForcedUnwind(_Unwind_Exception *exception_object, 247 _Unwind_Stop_Fn stop, void *stop_parameter); 248#else 249extern _Unwind_Reason_Code 250 _Unwind_ForcedUnwind(_Unwind_Exception *exception_object, 251 _Unwind_Stop_Fn stop, void *stop_parameter); 252#endif 253 254#if __USING_SJLJ_EXCEPTIONS__ 255typedef struct _Unwind_FunctionContext *_Unwind_FunctionContext_t; 256extern void _Unwind_SjLj_Register(_Unwind_FunctionContext_t fc); 257extern void _Unwind_SjLj_Unregister(_Unwind_FunctionContext_t fc); 258#endif 259 260// 261// The following are semi-suppoted extensions to the C++ ABI 262// 263 264// 265// called by __cxa_rethrow(). 266// 267#if __USING_SJLJ_EXCEPTIONS__ 268extern _Unwind_Reason_Code 269 _Unwind_SjLj_Resume_or_Rethrow(_Unwind_Exception *exception_object); 270#else 271extern _Unwind_Reason_Code 272 _Unwind_Resume_or_Rethrow(_Unwind_Exception *exception_object); 273#endif 274 275// _Unwind_Backtrace() is a gcc extension that walks the stack and calls the 276// _Unwind_Trace_Fn once per frame until it reaches the bottom of the stack 277// or the _Unwind_Trace_Fn function returns something other than _URC_NO_REASON. 278typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn)(struct _Unwind_Context *, 279 void *); 280extern _Unwind_Reason_Code _Unwind_Backtrace(_Unwind_Trace_Fn, void *); 281 282// _Unwind_GetCFA is a gcc extension that can be called from within a 283// personality handler to get the CFA (stack pointer before call) of 284// current frame. 285extern uintptr_t _Unwind_GetCFA(struct _Unwind_Context *); 286 287 288// _Unwind_GetIPInfo is a gcc extension that can be called from within a 289// personality handler. Similar to _Unwind_GetIP() but also returns in 290// *ipBefore a non-zero value if the instruction pointer is at or before the 291// instruction causing the unwind. Normally, in a function call, the IP returned 292// is the return address which is after the call instruction and may be past the 293// end of the function containing the call instruction. 294extern uintptr_t _Unwind_GetIPInfo(struct _Unwind_Context *context, 295 int *ipBefore); 296 297 298// __register_frame() is used with dynamically generated code to register the 299// FDE for a generated (JIT) code. The FDE must use pc-rel addressing to point 300// to its function and optional LSDA. 301// __register_frame() has existed in all versions of Mac OS X, but in 10.4 and 302// 10.5 it was buggy and did not actually register the FDE with the unwinder. 303// In 10.6 and later it does register properly. 304extern void __register_frame(const void *fde); 305extern void __deregister_frame(const void *fde); 306 307// _Unwind_Find_FDE() will locate the FDE if the pc is in some function that has 308// an associated FDE. Note, Mac OS X 10.6 and later, introduces "compact unwind 309// info" which the runtime uses in preference to dwarf unwind info. This 310// function will only work if the target function has an FDE but no compact 311// unwind info. 312struct dwarf_eh_bases { 313 uintptr_t tbase; 314 uintptr_t dbase; 315 uintptr_t func; 316}; 317extern const void *_Unwind_Find_FDE(const void *pc, struct dwarf_eh_bases *); 318 319 320// This function attempts to find the start (address of first instruction) of 321// a function given an address inside the function. It only works if the 322// function has an FDE (dwarf unwind info). 323// This function is unimplemented on Mac OS X 10.6 and later. Instead, use 324// _Unwind_Find_FDE() and look at the dwarf_eh_bases.func result. 325extern void *_Unwind_FindEnclosingFunction(void *pc); 326 327// Mac OS X does not support text-rel and data-rel addressing so these functions 328// are unimplemented 329extern uintptr_t _Unwind_GetDataRelBase(struct _Unwind_Context *context) 330 LIBUNWIND_UNAVAIL; 331extern uintptr_t _Unwind_GetTextRelBase(struct _Unwind_Context *context) 332 LIBUNWIND_UNAVAIL; 333 334// Mac OS X 10.4 and 10.5 had implementations of these functions in 335// libgcc_s.dylib, but they never worked. 336/// These functions are no longer available on Mac OS X. 337extern void __register_frame_info_bases(const void *fde, void *ob, void *tb, 338 void *db) LIBUNWIND_UNAVAIL; 339extern void __register_frame_info(const void *fde, void *ob) 340 LIBUNWIND_UNAVAIL; 341extern void __register_frame_info_table_bases(const void *fde, void *ob, 342 void *tb, void *db) 343 LIBUNWIND_UNAVAIL; 344extern void __register_frame_info_table(const void *fde, void *ob) 345 LIBUNWIND_UNAVAIL; 346extern void __register_frame_table(const void *fde) 347 LIBUNWIND_UNAVAIL; 348extern void *__deregister_frame_info(const void *fde) 349 LIBUNWIND_UNAVAIL; 350extern void *__deregister_frame_info_bases(const void *fde) 351 LIBUNWIND_UNAVAIL; 352 353#ifdef __cplusplus 354} 355#endif 356 357#endif // __UNWIND_H__ 358