1 //===--------------------------- Unwind-seh.cpp ---------------------------===// 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 // 9 // Implements SEH-based Itanium C++ exceptions. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "config.h" 14 15 #if defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 16 17 #include <unwind.h> 18 19 #include <stdint.h> 20 #include <stdbool.h> 21 #include <stdlib.h> 22 23 #include <windef.h> 24 #include <excpt.h> 25 #include <winnt.h> 26 #include <ntstatus.h> 27 28 #include "libunwind_ext.h" 29 #include "UnwindCursor.hpp" 30 31 using namespace libunwind; 32 33 #define STATUS_USER_DEFINED (1u << 29) 34 35 #define STATUS_GCC_MAGIC (('G' << 16) | ('C' << 8) | 'C') 36 37 #define MAKE_CUSTOM_STATUS(s, c) \ 38 ((NTSTATUS)(((s) << 30) | STATUS_USER_DEFINED | (c))) 39 #define MAKE_GCC_EXCEPTION(c) \ 40 MAKE_CUSTOM_STATUS(STATUS_SEVERITY_SUCCESS, STATUS_GCC_MAGIC | ((c) << 24)) 41 42 /// SEH exception raised by libunwind when the program calls 43 /// \c _Unwind_RaiseException. 44 #define STATUS_GCC_THROW MAKE_GCC_EXCEPTION(0) // 0x20474343 45 /// SEH exception raised by libunwind to initiate phase 2 of exception 46 /// handling. 47 #define STATUS_GCC_UNWIND MAKE_GCC_EXCEPTION(1) // 0x21474343 48 49 /// Class of foreign exceptions based on unrecognized SEH exceptions. 50 static const uint64_t kSEHExceptionClass = 0x434C4E4753454800; // CLNGSEH\0 51 52 // libunwind does not and should not depend on C++ library which means that we 53 // need our own declaration of global placement new. 54 void *operator new(size_t, void*); 55 56 /// Exception cleanup routine used by \c _GCC_specific_handler to 57 /// free foreign exceptions. 58 static void seh_exc_cleanup(_Unwind_Reason_Code urc, _Unwind_Exception *exc) { 59 (void)urc; 60 if (exc->exception_class != kSEHExceptionClass) 61 _LIBUNWIND_ABORT("SEH cleanup called on non-SEH exception"); 62 free(exc); 63 } 64 65 static int _unw_init_seh(unw_cursor_t *cursor, CONTEXT *ctx); 66 static DISPATCHER_CONTEXT *_unw_seh_get_disp_ctx(unw_cursor_t *cursor); 67 static void _unw_seh_set_disp_ctx(unw_cursor_t *cursor, DISPATCHER_CONTEXT *disp); 68 69 /// Common implementation of SEH-style handler functions used by Itanium- 70 /// style frames. Depending on how and why it was called, it may do one of: 71 /// a) Delegate to the given Itanium-style personality function; or 72 /// b) Initiate a collided unwind to halt unwinding. 73 _LIBUNWIND_EXPORT EXCEPTION_DISPOSITION 74 _GCC_specific_handler(PEXCEPTION_RECORD ms_exc, PVOID frame, PCONTEXT ms_ctx, 75 DISPATCHER_CONTEXT *disp, __personality_routine pers) { 76 unw_cursor_t cursor; 77 _Unwind_Exception *exc; 78 _Unwind_Action action; 79 struct _Unwind_Context *ctx = nullptr; 80 _Unwind_Reason_Code urc; 81 uintptr_t retval, target; 82 bool ours = false; 83 84 _LIBUNWIND_TRACE_UNWINDING("_GCC_specific_handler(%#010lx(%lx), %p)", 85 ms_exc->ExceptionCode, ms_exc->ExceptionFlags, 86 (void *)frame); 87 if (ms_exc->ExceptionCode == STATUS_GCC_UNWIND) { 88 if (IS_TARGET_UNWIND(ms_exc->ExceptionFlags)) { 89 // Set up the upper return value (the lower one and the target PC 90 // were set in the call to RtlUnwindEx()) for the landing pad. 91 #ifdef __x86_64__ 92 disp->ContextRecord->Rdx = ms_exc->ExceptionInformation[3]; 93 #elif defined(__arm__) 94 disp->ContextRecord->R1 = ms_exc->ExceptionInformation[3]; 95 #elif defined(__aarch64__) 96 disp->ContextRecord->X1 = ms_exc->ExceptionInformation[3]; 97 #endif 98 } 99 // This is the collided unwind to the landing pad. Nothing to do. 100 return ExceptionContinueSearch; 101 } 102 103 if (ms_exc->ExceptionCode == STATUS_GCC_THROW) { 104 // This is (probably) a libunwind-controlled exception/unwind. Recover the 105 // parameters which we set below, and pass them to the personality function. 106 ours = true; 107 exc = (_Unwind_Exception *)ms_exc->ExceptionInformation[0]; 108 if (!IS_UNWINDING(ms_exc->ExceptionFlags) && ms_exc->NumberParameters > 1) { 109 ctx = (struct _Unwind_Context *)ms_exc->ExceptionInformation[1]; 110 action = (_Unwind_Action)ms_exc->ExceptionInformation[2]; 111 } 112 } else { 113 // Foreign exception. 114 exc = (_Unwind_Exception *)malloc(sizeof(_Unwind_Exception)); 115 exc->exception_class = kSEHExceptionClass; 116 exc->exception_cleanup = seh_exc_cleanup; 117 memset(exc->private_, 0, sizeof(exc->private_)); 118 } 119 if (!ctx) { 120 _unw_init_seh(&cursor, disp->ContextRecord); 121 _unw_seh_set_disp_ctx(&cursor, disp); 122 unw_set_reg(&cursor, UNW_REG_IP, disp->ControlPc-1); 123 ctx = (struct _Unwind_Context *)&cursor; 124 125 if (!IS_UNWINDING(ms_exc->ExceptionFlags)) { 126 if (ours && ms_exc->NumberParameters > 1) 127 action = (_Unwind_Action)(_UA_CLEANUP_PHASE | _UA_FORCE_UNWIND); 128 else 129 action = _UA_SEARCH_PHASE; 130 } else { 131 if (ours && ms_exc->ExceptionInformation[1] == (ULONG_PTR)frame) 132 action = (_Unwind_Action)(_UA_CLEANUP_PHASE | _UA_HANDLER_FRAME); 133 else 134 action = _UA_CLEANUP_PHASE; 135 } 136 } 137 138 _LIBUNWIND_TRACE_UNWINDING("_GCC_specific_handler() calling personality " 139 "function %p(1, %d, %llx, %p, %p)", 140 (void *)pers, action, exc->exception_class, 141 (void *)exc, (void *)ctx); 142 urc = pers(1, action, exc->exception_class, exc, ctx); 143 _LIBUNWIND_TRACE_UNWINDING("_GCC_specific_handler() personality returned %d", urc); 144 switch (urc) { 145 case _URC_CONTINUE_UNWIND: 146 // If we're in phase 2, and the personality routine said to continue 147 // at the target frame, we're in real trouble. 148 if (action & _UA_HANDLER_FRAME) 149 _LIBUNWIND_ABORT("Personality continued unwind at the target frame!"); 150 return ExceptionContinueSearch; 151 case _URC_HANDLER_FOUND: 152 // If we were called by __libunwind_seh_personality(), indicate that 153 // a handler was found; otherwise, initiate phase 2 by unwinding. 154 if (ours && ms_exc->NumberParameters > 1) 155 return 4 /* ExecptionExecuteHandler in mingw */; 156 // This should never happen in phase 2. 157 if (IS_UNWINDING(ms_exc->ExceptionFlags)) 158 _LIBUNWIND_ABORT("Personality indicated exception handler in phase 2!"); 159 exc->private_[1] = (ULONG_PTR)frame; 160 if (ours) { 161 ms_exc->NumberParameters = 4; 162 ms_exc->ExceptionInformation[1] = (ULONG_PTR)frame; 163 } 164 // FIXME: Indicate target frame in foreign case! 165 // phase 2: the clean up phase 166 RtlUnwindEx(frame, (PVOID)disp->ControlPc, ms_exc, exc, ms_ctx, disp->HistoryTable); 167 _LIBUNWIND_ABORT("RtlUnwindEx() failed"); 168 case _URC_INSTALL_CONTEXT: { 169 // If we were called by __libunwind_seh_personality(), indicate that 170 // a handler was found; otherwise, it's time to initiate a collided 171 // unwind to the target. 172 if (ours && !IS_UNWINDING(ms_exc->ExceptionFlags) && ms_exc->NumberParameters > 1) 173 return 4 /* ExecptionExecuteHandler in mingw */; 174 // This should never happen in phase 1. 175 if (!IS_UNWINDING(ms_exc->ExceptionFlags)) 176 _LIBUNWIND_ABORT("Personality installed context during phase 1!"); 177 #ifdef __x86_64__ 178 exc->private_[2] = disp->TargetIp; 179 unw_get_reg(&cursor, UNW_X86_64_RAX, &retval); 180 unw_get_reg(&cursor, UNW_X86_64_RDX, &exc->private_[3]); 181 #elif defined(__arm__) 182 exc->private_[2] = disp->TargetPc; 183 unw_get_reg(&cursor, UNW_ARM_R0, &retval); 184 unw_get_reg(&cursor, UNW_ARM_R1, &exc->private_[3]); 185 #elif defined(__aarch64__) 186 exc->private_[2] = disp->TargetPc; 187 unw_get_reg(&cursor, UNW_ARM64_X0, &retval); 188 unw_get_reg(&cursor, UNW_ARM64_X1, &exc->private_[3]); 189 #endif 190 unw_get_reg(&cursor, UNW_REG_IP, &target); 191 ms_exc->ExceptionCode = STATUS_GCC_UNWIND; 192 #ifdef __x86_64__ 193 ms_exc->ExceptionInformation[2] = disp->TargetIp; 194 #elif defined(__arm__) || defined(__aarch64__) 195 ms_exc->ExceptionInformation[2] = disp->TargetPc; 196 #endif 197 ms_exc->ExceptionInformation[3] = exc->private_[3]; 198 // Give NTRTL some scratch space to keep track of the collided unwind. 199 // Don't use the one that was passed in; we don't want to overwrite the 200 // context in the DISPATCHER_CONTEXT. 201 CONTEXT new_ctx; 202 RtlUnwindEx(frame, (PVOID)target, ms_exc, (PVOID)retval, &new_ctx, disp->HistoryTable); 203 _LIBUNWIND_ABORT("RtlUnwindEx() failed"); 204 } 205 // Anything else indicates a serious problem. 206 default: return ExceptionContinueExecution; 207 } 208 } 209 210 /// Personality function returned by \c unw_get_proc_info() in SEH contexts. 211 /// This is a wrapper that calls the real SEH handler function, which in 212 /// turn (at least, for Itanium-style frames) calls the real Itanium 213 /// personality function (see \c _GCC_specific_handler()). 214 extern "C" _Unwind_Reason_Code 215 __libunwind_seh_personality(int version, _Unwind_Action state, 216 uint64_t klass, _Unwind_Exception *exc, 217 struct _Unwind_Context *context) { 218 (void)version; 219 (void)klass; 220 EXCEPTION_RECORD ms_exc; 221 bool phase2 = (state & (_UA_SEARCH_PHASE|_UA_CLEANUP_PHASE)) == _UA_CLEANUP_PHASE; 222 ms_exc.ExceptionCode = STATUS_GCC_THROW; 223 ms_exc.ExceptionFlags = 0; 224 ms_exc.NumberParameters = 3; 225 ms_exc.ExceptionInformation[0] = (ULONG_PTR)exc; 226 ms_exc.ExceptionInformation[1] = (ULONG_PTR)context; 227 ms_exc.ExceptionInformation[2] = state; 228 DISPATCHER_CONTEXT *disp_ctx = _unw_seh_get_disp_ctx((unw_cursor_t *)context); 229 EXCEPTION_DISPOSITION ms_act = disp_ctx->LanguageHandler(&ms_exc, 230 (PVOID)disp_ctx->EstablisherFrame, 231 disp_ctx->ContextRecord, 232 disp_ctx); 233 switch (ms_act) { 234 case ExceptionContinueSearch: return _URC_CONTINUE_UNWIND; 235 case 4 /*ExceptionExecuteHandler*/: 236 return phase2 ? _URC_INSTALL_CONTEXT : _URC_HANDLER_FOUND; 237 default: 238 return phase2 ? _URC_FATAL_PHASE2_ERROR : _URC_FATAL_PHASE1_ERROR; 239 } 240 } 241 242 static _Unwind_Reason_Code 243 unwind_phase2_forced(unw_context_t *uc, 244 _Unwind_Exception *exception_object, 245 _Unwind_Stop_Fn stop, void *stop_parameter) { 246 unw_cursor_t cursor2; 247 unw_init_local(&cursor2, uc); 248 249 // Walk each frame until we reach where search phase said to stop 250 while (unw_step(&cursor2) > 0) { 251 252 // Update info about this frame. 253 unw_proc_info_t frameInfo; 254 if (unw_get_proc_info(&cursor2, &frameInfo) != UNW_ESUCCESS) { 255 _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): unw_step " 256 "failed => _URC_END_OF_STACK", 257 (void *)exception_object); 258 return _URC_FATAL_PHASE2_ERROR; 259 } 260 261 // When tracing, print state information. 262 if (_LIBUNWIND_TRACING_UNWINDING) { 263 char functionBuf[512]; 264 const char *functionName = functionBuf; 265 unw_word_t offset; 266 if ((unw_get_proc_name(&cursor2, functionBuf, sizeof(functionBuf), 267 &offset) != UNW_ESUCCESS) || 268 (frameInfo.start_ip + offset > frameInfo.end_ip)) 269 functionName = ".anonymous."; 270 _LIBUNWIND_TRACE_UNWINDING( 271 "unwind_phase2_forced(ex_ojb=%p): start_ip=0x%" PRIx64 272 ", func=%s, lsda=0x%" PRIx64 ", personality=0x%" PRIx64, 273 (void *)exception_object, frameInfo.start_ip, functionName, 274 frameInfo.lsda, frameInfo.handler); 275 } 276 277 // Call stop function at each frame. 278 _Unwind_Action action = 279 (_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE); 280 _Unwind_Reason_Code stopResult = 281 (*stop)(1, action, exception_object->exception_class, exception_object, 282 (struct _Unwind_Context *)(&cursor2), stop_parameter); 283 _LIBUNWIND_TRACE_UNWINDING( 284 "unwind_phase2_forced(ex_ojb=%p): stop function returned %d", 285 (void *)exception_object, stopResult); 286 if (stopResult != _URC_NO_REASON) { 287 _LIBUNWIND_TRACE_UNWINDING( 288 "unwind_phase2_forced(ex_ojb=%p): stopped by stop function", 289 (void *)exception_object); 290 return _URC_FATAL_PHASE2_ERROR; 291 } 292 293 // If there is a personality routine, tell it we are unwinding. 294 if (frameInfo.handler != 0) { 295 __personality_routine p = 296 (__personality_routine)(intptr_t)(frameInfo.handler); 297 _LIBUNWIND_TRACE_UNWINDING( 298 "unwind_phase2_forced(ex_ojb=%p): calling personality function %p", 299 (void *)exception_object, (void *)(uintptr_t)p); 300 _Unwind_Reason_Code personalityResult = 301 (*p)(1, action, exception_object->exception_class, exception_object, 302 (struct _Unwind_Context *)(&cursor2)); 303 switch (personalityResult) { 304 case _URC_CONTINUE_UNWIND: 305 _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): " 306 "personality returned " 307 "_URC_CONTINUE_UNWIND", 308 (void *)exception_object); 309 // Destructors called, continue unwinding 310 break; 311 case _URC_INSTALL_CONTEXT: 312 _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): " 313 "personality returned " 314 "_URC_INSTALL_CONTEXT", 315 (void *)exception_object); 316 // We may get control back if landing pad calls _Unwind_Resume(). 317 unw_resume(&cursor2); 318 break; 319 default: 320 // Personality routine returned an unknown result code. 321 _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): " 322 "personality returned %d, " 323 "_URC_FATAL_PHASE2_ERROR", 324 (void *)exception_object, personalityResult); 325 return _URC_FATAL_PHASE2_ERROR; 326 } 327 } 328 } 329 330 // Call stop function one last time and tell it we've reached the end 331 // of the stack. 332 _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): calling stop " 333 "function with _UA_END_OF_STACK", 334 (void *)exception_object); 335 _Unwind_Action lastAction = 336 (_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE | _UA_END_OF_STACK); 337 (*stop)(1, lastAction, exception_object->exception_class, exception_object, 338 (struct _Unwind_Context *)(&cursor2), stop_parameter); 339 340 // Clean up phase did not resume at the frame that the search phase said it 341 // would. 342 return _URC_FATAL_PHASE2_ERROR; 343 } 344 345 /// Called by \c __cxa_throw(). Only returns if there is a fatal error. 346 _LIBUNWIND_EXPORT _Unwind_Reason_Code 347 _Unwind_RaiseException(_Unwind_Exception *exception_object) { 348 _LIBUNWIND_TRACE_API("_Unwind_RaiseException(ex_obj=%p)", 349 (void *)exception_object); 350 351 // Mark that this is a non-forced unwind, so _Unwind_Resume() 352 // can do the right thing. 353 memset(exception_object->private_, 0, sizeof(exception_object->private_)); 354 355 // phase 1: the search phase 356 // We'll let the system do that for us. 357 RaiseException(STATUS_GCC_THROW, 0, 1, (ULONG_PTR *)&exception_object); 358 359 // If we get here, either something went horribly wrong or we reached the 360 // top of the stack. Either way, let libc++abi call std::terminate(). 361 return _URC_END_OF_STACK; 362 } 363 364 /// When \c _Unwind_RaiseException() is in phase2, it hands control 365 /// to the personality function at each frame. The personality 366 /// may force a jump to a landing pad in that function; the landing 367 /// pad code may then call \c _Unwind_Resume() to continue with the 368 /// unwinding. Note: the call to \c _Unwind_Resume() is from compiler 369 /// geneated user code. All other \c _Unwind_* routines are called 370 /// by the C++ runtime \c __cxa_* routines. 371 /// 372 /// Note: re-throwing an exception (as opposed to continuing the unwind) 373 /// is implemented by having the code call \c __cxa_rethrow() which 374 /// in turn calls \c _Unwind_Resume_or_Rethrow(). 375 _LIBUNWIND_EXPORT void 376 _Unwind_Resume(_Unwind_Exception *exception_object) { 377 _LIBUNWIND_TRACE_API("_Unwind_Resume(ex_obj=%p)", (void *)exception_object); 378 379 if (exception_object->private_[0] != 0) { 380 unw_context_t uc; 381 382 unw_getcontext(&uc); 383 unwind_phase2_forced(&uc, exception_object, 384 (_Unwind_Stop_Fn) exception_object->private_[0], 385 (void *)exception_object->private_[4]); 386 } else { 387 // Recover the parameters for the unwind from the exception object 388 // so we can start unwinding again. 389 EXCEPTION_RECORD ms_exc; 390 CONTEXT ms_ctx; 391 UNWIND_HISTORY_TABLE hist; 392 393 memset(&ms_exc, 0, sizeof(ms_exc)); 394 memset(&hist, 0, sizeof(hist)); 395 ms_exc.ExceptionCode = STATUS_GCC_THROW; 396 ms_exc.ExceptionFlags = EXCEPTION_NONCONTINUABLE; 397 ms_exc.NumberParameters = 4; 398 ms_exc.ExceptionInformation[0] = (ULONG_PTR)exception_object; 399 ms_exc.ExceptionInformation[1] = exception_object->private_[1]; 400 ms_exc.ExceptionInformation[2] = exception_object->private_[2]; 401 ms_exc.ExceptionInformation[3] = exception_object->private_[3]; 402 RtlUnwindEx((PVOID)exception_object->private_[1], 403 (PVOID)exception_object->private_[2], &ms_exc, 404 exception_object, &ms_ctx, &hist); 405 } 406 407 // Clients assume _Unwind_Resume() does not return, so all we can do is abort. 408 _LIBUNWIND_ABORT("_Unwind_Resume() can't return"); 409 } 410 411 /// Not used by C++. 412 /// Unwinds stack, calling "stop" function at each frame. 413 /// Could be used to implement \c longjmp(). 414 _LIBUNWIND_EXPORT _Unwind_Reason_Code 415 _Unwind_ForcedUnwind(_Unwind_Exception *exception_object, 416 _Unwind_Stop_Fn stop, void *stop_parameter) { 417 _LIBUNWIND_TRACE_API("_Unwind_ForcedUnwind(ex_obj=%p, stop=%p)", 418 (void *)exception_object, (void *)(uintptr_t)stop); 419 unw_context_t uc; 420 unw_getcontext(&uc); 421 422 // Mark that this is a forced unwind, so _Unwind_Resume() can do 423 // the right thing. 424 exception_object->private_[0] = (uintptr_t) stop; 425 exception_object->private_[4] = (uintptr_t) stop_parameter; 426 427 // do it 428 return unwind_phase2_forced(&uc, exception_object, stop, stop_parameter); 429 } 430 431 /// Called by personality handler during phase 2 to get LSDA for current frame. 432 _LIBUNWIND_EXPORT uintptr_t 433 _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) { 434 uintptr_t result = (uintptr_t)_unw_seh_get_disp_ctx((unw_cursor_t *)context)->HandlerData; 435 _LIBUNWIND_TRACE_API( 436 "_Unwind_GetLanguageSpecificData(context=%p) => 0x%" PRIxPTR, 437 (void *)context, result); 438 return result; 439 } 440 441 /// Called by personality handler during phase 2 to find the start of the 442 /// function. 443 _LIBUNWIND_EXPORT uintptr_t 444 _Unwind_GetRegionStart(struct _Unwind_Context *context) { 445 DISPATCHER_CONTEXT *disp = _unw_seh_get_disp_ctx((unw_cursor_t *)context); 446 uintptr_t result = (uintptr_t)disp->FunctionEntry->BeginAddress + disp->ImageBase; 447 _LIBUNWIND_TRACE_API("_Unwind_GetRegionStart(context=%p) => 0x%" PRIxPTR, 448 (void *)context, result); 449 return result; 450 } 451 452 static int 453 _unw_init_seh(unw_cursor_t *cursor, CONTEXT *context) { 454 #ifdef _LIBUNWIND_TARGET_X86_64 455 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_x86_64>( 456 context, LocalAddressSpace::sThisAddressSpace); 457 auto *co = reinterpret_cast<AbstractUnwindCursor *>(cursor); 458 co->setInfoBasedOnIPRegister(); 459 return UNW_ESUCCESS; 460 #elif defined(_LIBUNWIND_TARGET_ARM) 461 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_arm>( 462 context, LocalAddressSpace::sThisAddressSpace); 463 auto *co = reinterpret_cast<AbstractUnwindCursor *>(cursor); 464 co->setInfoBasedOnIPRegister(); 465 return UNW_ESUCCESS; 466 #elif defined(_LIBUNWIND_TARGET_AARCH64) 467 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_arm64>( 468 context, LocalAddressSpace::sThisAddressSpace); 469 auto *co = reinterpret_cast<AbstractUnwindCursor *>(cursor); 470 co->setInfoBasedOnIPRegister(); 471 return UNW_ESUCCESS; 472 #else 473 return UNW_EINVAL; 474 #endif 475 } 476 477 static DISPATCHER_CONTEXT * 478 _unw_seh_get_disp_ctx(unw_cursor_t *cursor) { 479 #ifdef _LIBUNWIND_TARGET_X86_64 480 return reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_x86_64> *>(cursor)->getDispatcherContext(); 481 #elif defined(_LIBUNWIND_TARGET_ARM) 482 return reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm> *>(cursor)->getDispatcherContext(); 483 #elif defined(_LIBUNWIND_TARGET_AARCH64) 484 return reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm64> *>(cursor)->getDispatcherContext(); 485 #else 486 return nullptr; 487 #endif 488 } 489 490 static void 491 _unw_seh_set_disp_ctx(unw_cursor_t *cursor, DISPATCHER_CONTEXT *disp) { 492 #ifdef _LIBUNWIND_TARGET_X86_64 493 reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_x86_64> *>(cursor)->setDispatcherContext(disp); 494 #elif defined(_LIBUNWIND_TARGET_ARM) 495 reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm> *>(cursor)->setDispatcherContext(disp); 496 #elif defined(_LIBUNWIND_TARGET_AARCH64) 497 reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm64> *>(cursor)->setDispatcherContext(disp); 498 #endif 499 } 500 501 #endif // defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) 502