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 <__libunwind_config.h> 18 19 #include <stdint.h> 20 #include <stddef.h> 21 22 #if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__) && defined(_WIN32) 23 #include <windows.h> 24 #include <ntverp.h> 25 #endif 26 27 #if defined(__APPLE__) 28 #define LIBUNWIND_UNAVAIL __attribute__ (( unavailable )) 29 #else 30 #define LIBUNWIND_UNAVAIL 31 #endif 32 33 typedef enum { 34 _URC_NO_REASON = 0, 35 _URC_OK = 0, 36 _URC_FOREIGN_EXCEPTION_CAUGHT = 1, 37 _URC_FATAL_PHASE2_ERROR = 2, 38 _URC_FATAL_PHASE1_ERROR = 3, 39 _URC_NORMAL_STOP = 4, 40 _URC_END_OF_STACK = 5, 41 _URC_HANDLER_FOUND = 6, 42 _URC_INSTALL_CONTEXT = 7, 43 _URC_CONTINUE_UNWIND = 8, 44 #if defined(_LIBUNWIND_ARM_EHABI) 45 _URC_FAILURE = 9 46 #endif 47 } _Unwind_Reason_Code; 48 49 typedef enum { 50 _UA_SEARCH_PHASE = 1, 51 _UA_CLEANUP_PHASE = 2, 52 _UA_HANDLER_FRAME = 4, 53 _UA_FORCE_UNWIND = 8, 54 _UA_END_OF_STACK = 16 // gcc extension to C++ ABI 55 } _Unwind_Action; 56 57 typedef struct _Unwind_Context _Unwind_Context; // opaque 58 59 #if defined(_LIBUNWIND_ARM_EHABI) 60 typedef uint32_t _Unwind_State; 61 62 static const _Unwind_State _US_VIRTUAL_UNWIND_FRAME = 0; 63 static const _Unwind_State _US_UNWIND_FRAME_STARTING = 1; 64 static const _Unwind_State _US_UNWIND_FRAME_RESUME = 2; 65 static const _Unwind_State _US_ACTION_MASK = 3; 66 /* Undocumented flag for force unwinding. */ 67 static const _Unwind_State _US_FORCE_UNWIND = 8; 68 69 typedef uint32_t _Unwind_EHT_Header; 70 71 struct _Unwind_Control_Block; 72 typedef struct _Unwind_Control_Block _Unwind_Control_Block; 73 typedef struct _Unwind_Control_Block _Unwind_Exception; /* Alias */ 74 75 struct _Unwind_Control_Block { 76 uint64_t exception_class; 77 void (*exception_cleanup)(_Unwind_Reason_Code, _Unwind_Control_Block*); 78 79 /* Unwinder cache, private fields for the unwinder's use */ 80 struct { 81 uint32_t reserved1; /* init reserved1 to 0, then don't touch */ 82 uint32_t reserved2; 83 uint32_t reserved3; 84 uint32_t reserved4; 85 uint32_t reserved5; 86 } unwinder_cache; 87 88 /* Propagation barrier cache (valid after phase 1): */ 89 struct { 90 uint32_t sp; 91 uint32_t bitpattern[5]; 92 } barrier_cache; 93 94 /* Cleanup cache (preserved over cleanup): */ 95 struct { 96 uint32_t bitpattern[4]; 97 } cleanup_cache; 98 99 /* Pr cache (for pr's benefit): */ 100 struct { 101 uint32_t fnstart; /* function start address */ 102 _Unwind_EHT_Header* ehtp; /* pointer to EHT entry header word */ 103 uint32_t additional; 104 uint32_t reserved1; 105 } pr_cache; 106 107 long long int :0; /* Enforce the 8-byte alignment */ 108 } __attribute__((__aligned__(8))); 109 110 typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn) 111 (_Unwind_State state, 112 _Unwind_Exception* exceptionObject, 113 struct _Unwind_Context* context); 114 115 typedef _Unwind_Reason_Code (*__personality_routine) 116 (_Unwind_State state, 117 _Unwind_Exception* exceptionObject, 118 struct _Unwind_Context* context); 119 #else 120 struct _Unwind_Context; // opaque 121 struct _Unwind_Exception; // forward declaration 122 typedef struct _Unwind_Exception _Unwind_Exception; 123 124 struct _Unwind_Exception { 125 uint64_t exception_class; 126 void (*exception_cleanup)(_Unwind_Reason_Code reason, 127 _Unwind_Exception *exc); 128 #if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__) 129 uintptr_t private_[6]; 130 #else 131 uintptr_t private_1; // non-zero means forced unwind 132 uintptr_t private_2; // holds sp that phase1 found for phase2 to use 133 #endif 134 #if __SIZEOF_POINTER__ == 4 135 // The implementation of _Unwind_Exception uses an attribute mode on the 136 // above fields which has the side effect of causing this whole struct to 137 // round up to 32 bytes in size (48 with SEH). To be more explicit, we add 138 // pad fields added for binary compatibility. 139 uint32_t reserved[3]; 140 #endif 141 // The Itanium ABI requires that _Unwind_Exception objects are "double-word 142 // aligned". GCC has interpreted this to mean "use the maximum useful 143 // alignment for the target"; so do we. 144 } __attribute__((__aligned__)); 145 146 typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn) 147 (int version, 148 _Unwind_Action actions, 149 uint64_t exceptionClass, 150 _Unwind_Exception* exceptionObject, 151 struct _Unwind_Context* context, 152 void* stop_parameter ); 153 154 typedef _Unwind_Reason_Code (*__personality_routine) 155 (int version, 156 _Unwind_Action actions, 157 uint64_t exceptionClass, 158 _Unwind_Exception* exceptionObject, 159 struct _Unwind_Context* context); 160 #endif 161 162 #ifdef __cplusplus 163 extern "C" { 164 #endif 165 166 // 167 // The following are the base functions documented by the C++ ABI 168 // 169 #ifdef __USING_SJLJ_EXCEPTIONS__ 170 extern _Unwind_Reason_Code 171 _Unwind_SjLj_RaiseException(_Unwind_Exception *exception_object); 172 extern void _Unwind_SjLj_Resume(_Unwind_Exception *exception_object); 173 #else 174 extern _Unwind_Reason_Code 175 _Unwind_RaiseException(_Unwind_Exception *exception_object); 176 extern void _Unwind_Resume(_Unwind_Exception *exception_object); 177 #endif 178 extern void _Unwind_DeleteException(_Unwind_Exception *exception_object); 179 180 #if defined(_LIBUNWIND_ARM_EHABI) 181 typedef enum { 182 _UVRSC_CORE = 0, /* integer register */ 183 _UVRSC_VFP = 1, /* vfp */ 184 _UVRSC_WMMXD = 3, /* Intel WMMX data register */ 185 _UVRSC_WMMXC = 4 /* Intel WMMX control register */ 186 } _Unwind_VRS_RegClass; 187 188 typedef enum { 189 _UVRSD_UINT32 = 0, 190 _UVRSD_VFPX = 1, 191 _UVRSD_UINT64 = 3, 192 _UVRSD_FLOAT = 4, 193 _UVRSD_DOUBLE = 5 194 } _Unwind_VRS_DataRepresentation; 195 196 typedef enum { 197 _UVRSR_OK = 0, 198 _UVRSR_NOT_IMPLEMENTED = 1, 199 _UVRSR_FAILED = 2 200 } _Unwind_VRS_Result; 201 202 extern void _Unwind_Complete(_Unwind_Exception* exception_object); 203 204 extern _Unwind_VRS_Result 205 _Unwind_VRS_Get(_Unwind_Context *context, _Unwind_VRS_RegClass regclass, 206 uint32_t regno, _Unwind_VRS_DataRepresentation representation, 207 void *valuep); 208 209 extern _Unwind_VRS_Result 210 _Unwind_VRS_Set(_Unwind_Context *context, _Unwind_VRS_RegClass regclass, 211 uint32_t regno, _Unwind_VRS_DataRepresentation representation, 212 void *valuep); 213 214 extern _Unwind_VRS_Result 215 _Unwind_VRS_Pop(_Unwind_Context *context, _Unwind_VRS_RegClass regclass, 216 uint32_t discriminator, 217 _Unwind_VRS_DataRepresentation representation); 218 #endif 219 220 #if !defined(_LIBUNWIND_ARM_EHABI) 221 222 extern uintptr_t _Unwind_GetGR(struct _Unwind_Context *context, int index); 223 extern void _Unwind_SetGR(struct _Unwind_Context *context, int index, 224 uintptr_t new_value); 225 extern uintptr_t _Unwind_GetIP(struct _Unwind_Context *context); 226 extern void _Unwind_SetIP(struct _Unwind_Context *, uintptr_t new_value); 227 228 #else // defined(_LIBUNWIND_ARM_EHABI) 229 230 #if defined(_LIBUNWIND_UNWIND_LEVEL1_EXTERNAL_LINKAGE) 231 #define _LIBUNWIND_EXPORT_UNWIND_LEVEL1 extern 232 #else 233 #define _LIBUNWIND_EXPORT_UNWIND_LEVEL1 static __inline__ 234 #endif 235 236 // These are de facto helper functions for ARM, which delegate the function 237 // calls to _Unwind_VRS_Get/Set(). These are not a part of ARM EHABI 238 // specification, thus these function MUST be inlined. Please don't replace 239 // these with the "extern" function declaration; otherwise, the program 240 // including this <unwind.h> header won't be ABI compatible and will result in 241 // link error when we are linking the program with libgcc. 242 243 _LIBUNWIND_EXPORT_UNWIND_LEVEL1 244 uintptr_t _Unwind_GetGR(struct _Unwind_Context *context, int index) { 245 uintptr_t value = 0; 246 _Unwind_VRS_Get(context, _UVRSC_CORE, (uint32_t)index, _UVRSD_UINT32, &value); 247 return value; 248 } 249 250 _LIBUNWIND_EXPORT_UNWIND_LEVEL1 251 void _Unwind_SetGR(struct _Unwind_Context *context, int index, 252 uintptr_t value) { 253 _Unwind_VRS_Set(context, _UVRSC_CORE, (uint32_t)index, _UVRSD_UINT32, &value); 254 } 255 256 _LIBUNWIND_EXPORT_UNWIND_LEVEL1 257 uintptr_t _Unwind_GetIP(struct _Unwind_Context *context) { 258 // remove the thumb-bit before returning 259 return _Unwind_GetGR(context, 15) & (~(uintptr_t)0x1); 260 } 261 262 _LIBUNWIND_EXPORT_UNWIND_LEVEL1 263 void _Unwind_SetIP(struct _Unwind_Context *context, uintptr_t value) { 264 uintptr_t thumb_bit = _Unwind_GetGR(context, 15) & ((uintptr_t)0x1); 265 _Unwind_SetGR(context, 15, value | thumb_bit); 266 } 267 #endif // defined(_LIBUNWIND_ARM_EHABI) 268 269 extern uintptr_t _Unwind_GetRegionStart(struct _Unwind_Context *context); 270 extern uintptr_t 271 _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context); 272 #ifdef __USING_SJLJ_EXCEPTIONS__ 273 extern _Unwind_Reason_Code 274 _Unwind_SjLj_ForcedUnwind(_Unwind_Exception *exception_object, 275 _Unwind_Stop_Fn stop, void *stop_parameter); 276 #else 277 extern _Unwind_Reason_Code 278 _Unwind_ForcedUnwind(_Unwind_Exception *exception_object, 279 _Unwind_Stop_Fn stop, void *stop_parameter); 280 #endif 281 282 #ifdef __USING_SJLJ_EXCEPTIONS__ 283 typedef struct _Unwind_FunctionContext *_Unwind_FunctionContext_t; 284 extern void _Unwind_SjLj_Register(_Unwind_FunctionContext_t fc); 285 extern void _Unwind_SjLj_Unregister(_Unwind_FunctionContext_t fc); 286 #endif 287 288 // 289 // The following are semi-suppoted extensions to the C++ ABI 290 // 291 292 // 293 // called by __cxa_rethrow(). 294 // 295 #ifdef __USING_SJLJ_EXCEPTIONS__ 296 extern _Unwind_Reason_Code 297 _Unwind_SjLj_Resume_or_Rethrow(_Unwind_Exception *exception_object); 298 #else 299 extern _Unwind_Reason_Code 300 _Unwind_Resume_or_Rethrow(_Unwind_Exception *exception_object); 301 #endif 302 303 // _Unwind_Backtrace() is a gcc extension that walks the stack and calls the 304 // _Unwind_Trace_Fn once per frame until it reaches the bottom of the stack 305 // or the _Unwind_Trace_Fn function returns something other than _URC_NO_REASON. 306 typedef _Unwind_Reason_Code (*_Unwind_Trace_Fn)(struct _Unwind_Context *, 307 void *); 308 extern _Unwind_Reason_Code _Unwind_Backtrace(_Unwind_Trace_Fn, void *); 309 310 // _Unwind_GetCFA is a gcc extension that can be called from within a 311 // personality handler to get the CFA (stack pointer before call) of 312 // current frame. 313 extern uintptr_t _Unwind_GetCFA(struct _Unwind_Context *); 314 315 316 // _Unwind_GetIPInfo is a gcc extension that can be called from within a 317 // personality handler. Similar to _Unwind_GetIP() but also returns in 318 // *ipBefore a non-zero value if the instruction pointer is at or before the 319 // instruction causing the unwind. Normally, in a function call, the IP returned 320 // is the return address which is after the call instruction and may be past the 321 // end of the function containing the call instruction. 322 extern uintptr_t _Unwind_GetIPInfo(struct _Unwind_Context *context, 323 int *ipBefore); 324 325 326 // __register_frame() is used with dynamically generated code to register the 327 // FDE for a generated (JIT) code. The FDE must use pc-rel addressing to point 328 // to its function and optional LSDA. 329 // __register_frame() has existed in all versions of Mac OS X, but in 10.4 and 330 // 10.5 it was buggy and did not actually register the FDE with the unwinder. 331 // In 10.6 and later it does register properly. 332 extern void __register_frame(const void *fde); 333 extern void __deregister_frame(const void *fde); 334 335 // _Unwind_Find_FDE() will locate the FDE if the pc is in some function that has 336 // an associated FDE. Note, Mac OS X 10.6 and later, introduces "compact unwind 337 // info" which the runtime uses in preference to DWARF unwind info. This 338 // function will only work if the target function has an FDE but no compact 339 // unwind info. 340 struct dwarf_eh_bases { 341 uintptr_t tbase; 342 uintptr_t dbase; 343 uintptr_t func; 344 }; 345 extern const void *_Unwind_Find_FDE(const void *pc, struct dwarf_eh_bases *); 346 347 348 // This function attempts to find the start (address of first instruction) of 349 // a function given an address inside the function. It only works if the 350 // function has an FDE (DWARF unwind info). 351 // This function is unimplemented on Mac OS X 10.6 and later. Instead, use 352 // _Unwind_Find_FDE() and look at the dwarf_eh_bases.func result. 353 extern void *_Unwind_FindEnclosingFunction(void *pc); 354 355 // Mac OS X does not support text-rel and data-rel addressing so these functions 356 // are unimplemented 357 extern uintptr_t _Unwind_GetDataRelBase(struct _Unwind_Context *context) 358 LIBUNWIND_UNAVAIL; 359 extern uintptr_t _Unwind_GetTextRelBase(struct _Unwind_Context *context) 360 LIBUNWIND_UNAVAIL; 361 362 // Mac OS X 10.4 and 10.5 had implementations of these functions in 363 // libgcc_s.dylib, but they never worked. 364 /// These functions are no longer available on Mac OS X. 365 extern void __register_frame_info_bases(const void *fde, void *ob, void *tb, 366 void *db) LIBUNWIND_UNAVAIL; 367 extern void __register_frame_info(const void *fde, void *ob) 368 LIBUNWIND_UNAVAIL; 369 extern void __register_frame_info_table_bases(const void *fde, void *ob, 370 void *tb, void *db) 371 LIBUNWIND_UNAVAIL; 372 extern void __register_frame_info_table(const void *fde, void *ob) 373 LIBUNWIND_UNAVAIL; 374 extern void __register_frame_table(const void *fde) 375 LIBUNWIND_UNAVAIL; 376 extern void *__deregister_frame_info(const void *fde) 377 LIBUNWIND_UNAVAIL; 378 extern void *__deregister_frame_info_bases(const void *fde) 379 LIBUNWIND_UNAVAIL; 380 381 #if defined(__SEH__) && !defined(__USING_SJLJ_EXCEPTIONS__) 382 #ifndef _WIN32 383 typedef struct _EXCEPTION_RECORD EXCEPTION_RECORD; 384 typedef struct _CONTEXT CONTEXT; 385 typedef struct _DISPATCHER_CONTEXT DISPATCHER_CONTEXT; 386 #elif !defined(__MINGW32__) && VER_PRODUCTBUILD < 8000 387 typedef struct _DISPATCHER_CONTEXT DISPATCHER_CONTEXT; 388 #endif 389 // This is the common wrapper for GCC-style personality functions with SEH. 390 extern EXCEPTION_DISPOSITION _GCC_specific_handler(EXCEPTION_RECORD *exc, 391 void *frame, 392 CONTEXT *ctx, 393 DISPATCHER_CONTEXT *disp, 394 __personality_routine pers); 395 #endif 396 397 #ifdef __cplusplus 398 } 399 #endif 400 401 #endif // __UNWIND_H__ 402