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 34 typedef 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 50 typedef 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 58 typedef struct _Unwind_Context _Unwind_Context; // opaque 59 60 #if LIBCXXABI_ARM_EHABI 61 typedef uint32_t _Unwind_State; 62 63 static const _Unwind_State _US_VIRTUAL_UNWIND_FRAME = 0; 64 static const _Unwind_State _US_UNWIND_FRAME_STARTING = 1; 65 static const _Unwind_State _US_UNWIND_FRAME_RESUME = 2; 66 67 typedef uint32_t _Unwind_EHT_Header; 68 69 struct _Unwind_Control_Block; 70 typedef struct _Unwind_Control_Block _Unwind_Control_Block; 71 typedef struct _Unwind_Control_Block _Unwind_Exception; /* Alias */ 72 73 struct _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 }; 107 108 typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn) 109 (_Unwind_State state, 110 _Unwind_Exception* exceptionObject, 111 struct _Unwind_Context* context); 112 113 typedef _Unwind_Reason_Code (*__personality_routine) 114 (_Unwind_State state, 115 _Unwind_Exception* exceptionObject, 116 struct _Unwind_Context* context); 117 #else 118 struct _Unwind_Context; // opaque 119 struct _Unwind_Exception; // forward declaration 120 typedef struct _Unwind_Exception _Unwind_Exception; 121 122 struct _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 }; 136 137 typedef _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 ); 144 145 typedef _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 154 extern "C" { 155 #endif 156 157 // 158 // The following are the base functions documented by the C++ ABI 159 // 160 #if __USING_SJLJ_EXCEPTIONS__ 161 extern _Unwind_Reason_Code 162 _Unwind_SjLj_RaiseException(_Unwind_Exception *exception_object); 163 extern void _Unwind_SjLj_Resume(_Unwind_Exception *exception_object); 164 #else 165 extern _Unwind_Reason_Code 166 _Unwind_RaiseException(_Unwind_Exception *exception_object); 167 extern void _Unwind_Resume(_Unwind_Exception *exception_object); 168 #endif 169 extern void _Unwind_DeleteException(_Unwind_Exception *exception_object); 170 171 #if LIBCXXABI_ARM_EHABI 172 typedef 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; 178 179 typedef 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; 186 187 typedef enum { 188 _UVRSR_OK = 0, 189 _UVRSR_NOT_IMPLEMENTED = 1, 190 _UVRSR_FAILED = 2 191 } _Unwind_VRS_Result; 192 193 extern void _Unwind_Complete(_Unwind_Exception* exception_object); 194 195 extern _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); 199 200 extern _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); 204 205 extern _Unwind_VRS_Result 206 _Unwind_VRS_Pop(_Unwind_Context *context, _Unwind_VRS_RegClass regclass, 207 uint32_t discriminator, 208 _Unwind_VRS_DataRepresentation representation); 209 210 static 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 } 216 217 static 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 } 222 223 static 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 } 227 228 static 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 234 extern uintptr_t _Unwind_GetGR(struct _Unwind_Context *context, int index); 235 extern void _Unwind_SetGR(struct _Unwind_Context *context, int index, 236 uintptr_t new_value); 237 extern uintptr_t _Unwind_GetIP(struct _Unwind_Context *context); 238 extern void _Unwind_SetIP(struct _Unwind_Context *, uintptr_t new_value); 239 #endif 240 241 extern uintptr_t _Unwind_GetRegionStart(struct _Unwind_Context *context); 242 extern uintptr_t 243 _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context); 244 #if __USING_SJLJ_EXCEPTIONS__ 245 extern _Unwind_Reason_Code 246 _Unwind_SjLj_ForcedUnwind(_Unwind_Exception *exception_object, 247 _Unwind_Stop_Fn stop, void *stop_parameter); 248 #else 249 extern _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__ 255 typedef struct _Unwind_FunctionContext *_Unwind_FunctionContext_t; 256 extern void _Unwind_SjLj_Register(_Unwind_FunctionContext_t fc); 257 extern 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__ 268 extern _Unwind_Reason_Code 269 _Unwind_SjLj_Resume_or_Rethrow(_Unwind_Exception *exception_object); 270 #else 271 extern _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. 278 typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn)(struct _Unwind_Context *, 279 void *); 280 extern _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. 285 extern 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. 294 extern 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. 304 extern void __register_frame(const void *fde); 305 extern 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. 312 struct dwarf_eh_bases { 313 uintptr_t tbase; 314 uintptr_t dbase; 315 uintptr_t func; 316 }; 317 extern 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. 325 extern 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 329 extern uintptr_t _Unwind_GetDataRelBase(struct _Unwind_Context *context) 330 LIBUNWIND_UNAVAIL; 331 extern 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. 337 extern void __register_frame_info_bases(const void *fde, void *ob, void *tb, 338 void *db) LIBUNWIND_UNAVAIL; 339 extern void __register_frame_info(const void *fde, void *ob) 340 LIBUNWIND_UNAVAIL; 341 extern void __register_frame_info_table_bases(const void *fde, void *ob, 342 void *tb, void *db) 343 LIBUNWIND_UNAVAIL; 344 extern void __register_frame_info_table(const void *fde, void *ob) 345 LIBUNWIND_UNAVAIL; 346 extern void __register_frame_table(const void *fde) 347 LIBUNWIND_UNAVAIL; 348 extern void *__deregister_frame_info(const void *fde) 349 LIBUNWIND_UNAVAIL; 350 extern void *__deregister_frame_info_bases(const void *fde) 351 LIBUNWIND_UNAVAIL; 352 353 #ifdef __cplusplus 354 } 355 #endif 356 357 #endif // __UNWIND_H__ 358
