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//
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
31using 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
49static int __unw_init_seh(unw_cursor_t *cursor, CONTEXT *ctx);
50static DISPATCHER_CONTEXT *__unw_seh_get_disp_ctx(unw_cursor_t *cursor);
51static void __unw_seh_set_disp_ctx(unw_cursor_t *cursor,
52 DISPATCHER_CONTEXT *disp);
53
54/// Common implementation of SEH-style handler functions used by Itanium-
55/// style frames. Depending on how and why it was called, it may do one of:
56/// a) Delegate to the given Itanium-style personality function; or
57/// b) Initiate a collided unwind to halt unwinding.
58_LIBUNWIND_EXPORT EXCEPTION_DISPOSITION
59_GCC_specific_handler(PEXCEPTION_RECORD ms_exc, PVOID frame, PCONTEXT ms_ctx,
60 DISPATCHER_CONTEXT *disp, _Unwind_Personality_Fn pers) {
61 unw_cursor_t cursor;
62 _Unwind_Exception *exc;
63 _Unwind_Action action;
64 struct _Unwind_Context *ctx = nullptr;
65 _Unwind_Reason_Code urc;
66 uintptr_t retval, target;
67 bool ours = false;
68
69 _LIBUNWIND_TRACE_UNWINDING("_GCC_specific_handler(%#010lx(%lx), %p)",
70 ms_exc->ExceptionCode, ms_exc->ExceptionFlags,
71 (void *)frame);
72 if (ms_exc->ExceptionCode == STATUS_GCC_UNWIND) {
73 if (IS_TARGET_UNWIND(ms_exc->ExceptionFlags)) {
74 // Set up the upper return value (the lower one and the target PC
75 // were set in the call to RtlUnwindEx()) for the landing pad.
76#ifdef __x86_64__
77 disp->ContextRecord->Rdx = ms_exc->ExceptionInformation[3];
78#elif defined(__arm__)
79 disp->ContextRecord->R1 = ms_exc->ExceptionInformation[3];
80#elif defined(__aarch64__)
81 disp->ContextRecord->X1 = ms_exc->ExceptionInformation[3];
82#endif
83 }
84 // This is the collided unwind to the landing pad. Nothing to do.
85 return ExceptionContinueSearch;
86 }
87
88 if (ms_exc->ExceptionCode == STATUS_GCC_THROW) {
89 // This is (probably) a libunwind-controlled exception/unwind. Recover the
90 // parameters which we set below, and pass them to the personality function.
91 ours = true;
92 exc = (_Unwind_Exception *)ms_exc->ExceptionInformation[0];
93 if (!IS_UNWINDING(ms_exc->ExceptionFlags) && ms_exc->NumberParameters > 1) {
94 ctx = (struct _Unwind_Context *)ms_exc->ExceptionInformation[1];
95 action = (_Unwind_Action)ms_exc->ExceptionInformation[2];
96 }
97 } else {
98 // Foreign exception.
99 // We can't interact with them (we don't know the original target frame
100 // that we should pass on to RtlUnwindEx in _Unwind_Resume), so just
101 // pass without calling our destructors here.
102 return ExceptionContinueSearch;
103 }
104 if (!ctx) {
105 __unw_init_seh(&cursor, disp->ContextRecord);
106 __unw_seh_set_disp_ctx(&cursor, disp);
107 __unw_set_reg(&cursor, UNW_REG_IP, disp->ControlPc);
108 ctx = (struct _Unwind_Context *)&cursor;
109
110 if (!IS_UNWINDING(ms_exc->ExceptionFlags)) {
111 if (ours && ms_exc->NumberParameters > 1)
112 action = (_Unwind_Action)(_UA_CLEANUP_PHASE | _UA_FORCE_UNWIND);
113 else
114 action = _UA_SEARCH_PHASE;
115 } else {
116 if (ours && ms_exc->ExceptionInformation[1] == (ULONG_PTR)frame)
117 action = (_Unwind_Action)(_UA_CLEANUP_PHASE | _UA_HANDLER_FRAME);
118 else
119 action = _UA_CLEANUP_PHASE;
120 }
121 }
122
123 _LIBUNWIND_TRACE_UNWINDING("_GCC_specific_handler() calling personality "
124 "function %p(1, %d, %llx, %p, %p)",
125 (void *)pers, action, exc->exception_class,
126 (void *)exc, (void *)ctx);
127 urc = pers(1, action, exc->exception_class, exc, ctx);
128 _LIBUNWIND_TRACE_UNWINDING("_GCC_specific_handler() personality returned %d", urc);
129 switch (urc) {
130 case _URC_CONTINUE_UNWIND:
131 // If we're in phase 2, and the personality routine said to continue
132 // at the target frame, we're in real trouble.
133 if (action & _UA_HANDLER_FRAME)
134 _LIBUNWIND_ABORT("Personality continued unwind at the target frame!");
135 return ExceptionContinueSearch;
136 case _URC_HANDLER_FOUND:
137 // If we were called by __libunwind_seh_personality(), indicate that
138 // a handler was found; otherwise, initiate phase 2 by unwinding.
139 if (ours && ms_exc->NumberParameters > 1)
140 return 4 /* ExceptionExecuteHandler in mingw */;
141 // This should never happen in phase 2.
142 if (IS_UNWINDING(ms_exc->ExceptionFlags))
143 _LIBUNWIND_ABORT("Personality indicated exception handler in phase 2!");
144 exc->private_[1] = (ULONG_PTR)frame;
145 if (ours) {
146 ms_exc->NumberParameters = 4;
147 ms_exc->ExceptionInformation[1] = (ULONG_PTR)frame;
148 }
149 // FIXME: Indicate target frame in foreign case!
150 // phase 2: the clean up phase
151 RtlUnwindEx(frame, (PVOID)disp->ControlPc, ms_exc, exc, ms_ctx, disp->HistoryTable);
152 _LIBUNWIND_ABORT("RtlUnwindEx() failed");
153 case _URC_INSTALL_CONTEXT: {
154 // If we were called by __libunwind_seh_personality(), indicate that
155 // a handler was found; otherwise, it's time to initiate a collided
156 // unwind to the target.
157 if (ours && !IS_UNWINDING(ms_exc->ExceptionFlags) && ms_exc->NumberParameters > 1)
158 return 4 /* ExceptionExecuteHandler in mingw */;
159 // This should never happen in phase 1.
160 if (!IS_UNWINDING(ms_exc->ExceptionFlags))
161 _LIBUNWIND_ABORT("Personality installed context during phase 1!");
162#ifdef __x86_64__
163 exc->private_[2] = disp->TargetIp;
164 __unw_get_reg(&cursor, UNW_X86_64_RAX, &retval);
165 __unw_get_reg(&cursor, UNW_X86_64_RDX, &exc->private_[3]);
166#elif defined(__arm__)
167 exc->private_[2] = disp->TargetPc;
168 __unw_get_reg(&cursor, UNW_ARM_R0, &retval);
169 __unw_get_reg(&cursor, UNW_ARM_R1, &exc->private_[3]);
170#elif defined(__aarch64__)
171 exc->private_[2] = disp->TargetPc;
172 __unw_get_reg(&cursor, UNW_AARCH64_X0, &retval);
173 __unw_get_reg(&cursor, UNW_AARCH64_X1, &exc->private_[3]);
174#endif
175 __unw_get_reg(&cursor, UNW_REG_IP, &target);
176 ms_exc->ExceptionCode = STATUS_GCC_UNWIND;
177#ifdef __x86_64__
178 ms_exc->ExceptionInformation[2] = disp->TargetIp;
179#elif defined(__arm__) || defined(__aarch64__)
180 ms_exc->ExceptionInformation[2] = disp->TargetPc;
181#endif
182 ms_exc->ExceptionInformation[3] = exc->private_[3];
183 // Give NTRTL some scratch space to keep track of the collided unwind.
184 // Don't use the one that was passed in; we don't want to overwrite the
185 // context in the DISPATCHER_CONTEXT.
186 CONTEXT new_ctx;
187 RtlUnwindEx(frame, (PVOID)target, ms_exc, (PVOID)retval, &new_ctx, disp->HistoryTable);
188 _LIBUNWIND_ABORT("RtlUnwindEx() failed");
189 }
190 // Anything else indicates a serious problem.
191 default: return ExceptionContinueExecution;
192 }
193}
194
195/// Personality function returned by \c __unw_get_proc_info() in SEH contexts.
196/// This is a wrapper that calls the real SEH handler function, which in
197/// turn (at least, for Itanium-style frames) calls the real Itanium
198/// personality function (see \c _GCC_specific_handler()).
199extern "C" _Unwind_Reason_Code
200__libunwind_seh_personality(int version, _Unwind_Action state,
201 uint64_t klass, _Unwind_Exception *exc,
202 struct _Unwind_Context *context) {
203 (void)version;
204 (void)klass;
205 EXCEPTION_RECORD ms_exc;
206 bool phase2 = (state & (_UA_SEARCH_PHASE|_UA_CLEANUP_PHASE)) == _UA_CLEANUP_PHASE;
207 ms_exc.ExceptionCode = STATUS_GCC_THROW;
208 ms_exc.ExceptionFlags = 0;
209 ms_exc.NumberParameters = 3;
210 ms_exc.ExceptionInformation[0] = (ULONG_PTR)exc;
211 ms_exc.ExceptionInformation[1] = (ULONG_PTR)context;
212 ms_exc.ExceptionInformation[2] = state;
213 DISPATCHER_CONTEXT *disp_ctx =
214 __unw_seh_get_disp_ctx((unw_cursor_t *)context);
215 _LIBUNWIND_TRACE_UNWINDING("__libunwind_seh_personality() calling "
216 "LanguageHandler %p(%p, %p, %p, %p)",
217 (void *)disp_ctx->LanguageHandler, (void *)&ms_exc,
218 (void *)disp_ctx->EstablisherFrame,
219 (void *)disp_ctx->ContextRecord, (void *)disp_ctx);
220 EXCEPTION_DISPOSITION ms_act = disp_ctx->LanguageHandler(&ms_exc,
221 (PVOID)disp_ctx->EstablisherFrame,
222 disp_ctx->ContextRecord,
223 disp_ctx);
224 _LIBUNWIND_TRACE_UNWINDING("__libunwind_seh_personality() LanguageHandler "
225 "returned %d",
226 (int)ms_act);
227 switch (ms_act) {
228 case ExceptionContinueExecution: return _URC_END_OF_STACK;
229 case ExceptionContinueSearch: return _URC_CONTINUE_UNWIND;
230 case 4 /*ExceptionExecuteHandler*/:
231 return phase2 ? _URC_INSTALL_CONTEXT : _URC_HANDLER_FOUND;
232 default:
233 return phase2 ? _URC_FATAL_PHASE2_ERROR : _URC_FATAL_PHASE1_ERROR;
234 }
235}
236
237static _Unwind_Reason_Code
238unwind_phase2_forced(unw_context_t *uc,
239 _Unwind_Exception *exception_object,
240 _Unwind_Stop_Fn stop, void *stop_parameter) {
241 unw_cursor_t cursor2;
242 __unw_init_local(&cursor2, uc);
243
244 // Walk each frame until we reach where search phase said to stop
245 while (__unw_step(&cursor2) > 0) {
246
247 // Update info about this frame.
248 unw_proc_info_t frameInfo;
249 if (__unw_get_proc_info(&cursor2, &frameInfo) != UNW_ESUCCESS) {
250 _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): __unw_get_proc_info "
251 "failed => _URC_END_OF_STACK",
252 (void *)exception_object);
253 return _URC_FATAL_PHASE2_ERROR;
254 }
255
256#ifndef NDEBUG
257 // When tracing, print state information.
258 if (_LIBUNWIND_TRACING_UNWINDING) {
259 char functionBuf[512];
260 const char *functionName = functionBuf;
261 unw_word_t offset;
262 if ((__unw_get_proc_name(&cursor2, functionBuf, sizeof(functionBuf),
263 &offset) != UNW_ESUCCESS) ||
264 (frameInfo.start_ip + offset > frameInfo.end_ip))
265 functionName = ".anonymous.";
266 _LIBUNWIND_TRACE_UNWINDING(
267 "unwind_phase2_forced(ex_ojb=%p): start_ip=0x%" PRIxPTR
268 ", func=%s, lsda=0x%" PRIxPTR ", personality=0x%" PRIxPTR,
269 (void *)exception_object, frameInfo.start_ip, functionName,
270 frameInfo.lsda, frameInfo.handler);
271 }
272#endif
273
274 // Call stop function at each frame.
275 _Unwind_Action action =
276 (_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE);
277 _Unwind_Reason_Code stopResult =
278 (*stop)(1, action, exception_object->exception_class, exception_object,
279 (struct _Unwind_Context *)(&cursor2), stop_parameter);
280 _LIBUNWIND_TRACE_UNWINDING(
281 "unwind_phase2_forced(ex_ojb=%p): stop function returned %d",
282 (void *)exception_object, stopResult);
283 if (stopResult != _URC_NO_REASON) {
284 _LIBUNWIND_TRACE_UNWINDING(
285 "unwind_phase2_forced(ex_ojb=%p): stopped by stop function",
286 (void *)exception_object);
287 return _URC_FATAL_PHASE2_ERROR;
288 }
289
290 // If there is a personality routine, tell it we are unwinding.
291 if (frameInfo.handler != 0) {
292 _Unwind_Personality_Fn p =
293 (_Unwind_Personality_Fn)(intptr_t)(frameInfo.handler);
294 _LIBUNWIND_TRACE_UNWINDING(
295 "unwind_phase2_forced(ex_ojb=%p): calling personality function %p",
296 (void *)exception_object, (void *)(uintptr_t)p);
297 _Unwind_Reason_Code personalityResult =
298 (*p)(1, action, exception_object->exception_class, exception_object,
299 (struct _Unwind_Context *)(&cursor2));
300 switch (personalityResult) {
301 case _URC_CONTINUE_UNWIND:
302 _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
303 "personality returned "
304 "_URC_CONTINUE_UNWIND",
305 (void *)exception_object);
306 // Destructors called, continue unwinding
307 break;
308 case _URC_INSTALL_CONTEXT:
309 _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
310 "personality returned "
311 "_URC_INSTALL_CONTEXT",
312 (void *)exception_object);
313 // We may get control back if landing pad calls _Unwind_Resume().
314 __unw_resume(&cursor2);
315 break;
316 case _URC_END_OF_STACK:
317 _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
318 "personality returned "
319 "_URC_END_OF_STACK",
320 (void *)exception_object);
321 break;
322 default:
323 // Personality routine returned an unknown result code.
324 _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
325 "personality returned %d, "
326 "_URC_FATAL_PHASE2_ERROR",
327 (void *)exception_object, personalityResult);
328 return _URC_FATAL_PHASE2_ERROR;
329 }
330 if (personalityResult == _URC_END_OF_STACK)
331 break;
332 }
333 }
334
335 // Call stop function one last time and tell it we've reached the end
336 // of the stack.
337 _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): calling stop "
338 "function with _UA_END_OF_STACK",
339 (void *)exception_object);
340 _Unwind_Action lastAction =
341 (_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE | _UA_END_OF_STACK);
342 (*stop)(1, lastAction, exception_object->exception_class, exception_object,
343 (struct _Unwind_Context *)(&cursor2), stop_parameter);
344
345 // Clean up phase did not resume at the frame that the search phase said it
346 // would.
347 return _URC_FATAL_PHASE2_ERROR;
348}
349
350/// Called by \c __cxa_throw(). Only returns if there is a fatal error.
351_LIBUNWIND_EXPORT _Unwind_Reason_Code
352_Unwind_RaiseException(_Unwind_Exception *exception_object) {
353 _LIBUNWIND_TRACE_API("_Unwind_RaiseException(ex_obj=%p)",
354 (void *)exception_object);
355
356 // Mark that this is a non-forced unwind, so _Unwind_Resume()
357 // can do the right thing.
358 memset(exception_object->private_, 0, sizeof(exception_object->private_));
359
360 // phase 1: the search phase
361 // We'll let the system do that for us.
362 RaiseException(STATUS_GCC_THROW, 0, 1, (ULONG_PTR *)&exception_object);
363
364 // If we get here, either something went horribly wrong or we reached the
365 // top of the stack. Either way, let libc++abi call std::terminate().
366 return _URC_END_OF_STACK;
367}
368
369/// When \c _Unwind_RaiseException() is in phase2, it hands control
370/// to the personality function at each frame. The personality
371/// may force a jump to a landing pad in that function; the landing
372/// pad code may then call \c _Unwind_Resume() to continue with the
373/// unwinding. Note: the call to \c _Unwind_Resume() is from compiler
374/// generated user code. All other \c _Unwind_* routines are called
375/// by the C++ runtime \c __cxa_* routines.
376///
377/// Note: re-throwing an exception (as opposed to continuing the unwind)
378/// is implemented by having the code call \c __cxa_rethrow() which
379/// in turn calls \c _Unwind_Resume_or_Rethrow().
380_LIBUNWIND_EXPORT void
381_Unwind_Resume(_Unwind_Exception *exception_object) {
382 _LIBUNWIND_TRACE_API("_Unwind_Resume(ex_obj=%p)", (void *)exception_object);
383
384 if (exception_object->private_[0] != 0) {
385 unw_context_t uc;
386
387 __unw_getcontext(&uc);
388 unwind_phase2_forced(&uc, exception_object,
389 (_Unwind_Stop_Fn) exception_object->private_[0],
390 (void *)exception_object->private_[4]);
391 } else {
392 // Recover the parameters for the unwind from the exception object
393 // so we can start unwinding again.
394 EXCEPTION_RECORD ms_exc;
395 CONTEXT ms_ctx;
396 UNWIND_HISTORY_TABLE hist;
397
398 memset(&ms_exc, 0, sizeof(ms_exc));
399 memset(&hist, 0, sizeof(hist));
400 ms_exc.ExceptionCode = STATUS_GCC_THROW;
401 ms_exc.ExceptionFlags = EXCEPTION_NONCONTINUABLE;
402 ms_exc.NumberParameters = 4;
403 ms_exc.ExceptionInformation[0] = (ULONG_PTR)exception_object;
404 ms_exc.ExceptionInformation[1] = exception_object->private_[1];
405 ms_exc.ExceptionInformation[2] = exception_object->private_[2];
406 ms_exc.ExceptionInformation[3] = exception_object->private_[3];
407 RtlUnwindEx((PVOID)exception_object->private_[1],
408 (PVOID)exception_object->private_[2], &ms_exc,
409 exception_object, &ms_ctx, &hist);
410 }
411
412 // Clients assume _Unwind_Resume() does not return, so all we can do is abort.
413 _LIBUNWIND_ABORT("_Unwind_Resume() can't return");
414}
415
416/// Not used by C++.
417/// Unwinds stack, calling "stop" function at each frame.
418/// Could be used to implement \c longjmp().
419_LIBUNWIND_EXPORT _Unwind_Reason_Code
420_Unwind_ForcedUnwind(_Unwind_Exception *exception_object,
421 _Unwind_Stop_Fn stop, void *stop_parameter) {
422 _LIBUNWIND_TRACE_API("_Unwind_ForcedUnwind(ex_obj=%p, stop=%p)",
423 (void *)exception_object, (void *)(uintptr_t)stop);
424 unw_context_t uc;
425 __unw_getcontext(&uc);
426
427 // Mark that this is a forced unwind, so _Unwind_Resume() can do
428 // the right thing.
429 exception_object->private_[0] = (uintptr_t) stop;
430 exception_object->private_[4] = (uintptr_t) stop_parameter;
431
432 // do it
433 return unwind_phase2_forced(&uc, exception_object, stop, stop_parameter);
434}
435
436/// Called by personality handler during phase 2 to get LSDA for current frame.
437_LIBUNWIND_EXPORT uintptr_t
438_Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) {
439 uintptr_t result =
440 (uintptr_t)__unw_seh_get_disp_ctx((unw_cursor_t *)context)->HandlerData;
441 _LIBUNWIND_TRACE_API(
442 "_Unwind_GetLanguageSpecificData(context=%p) => 0x%" PRIxPTR,
443 (void *)context, result);
444 return result;
445}
446
447/// Called by personality handler during phase 2 to find the start of the
448/// function.
449_LIBUNWIND_EXPORT uintptr_t
450_Unwind_GetRegionStart(struct _Unwind_Context *context) {
451 DISPATCHER_CONTEXT *disp = __unw_seh_get_disp_ctx((unw_cursor_t *)context);
452 uintptr_t result = (uintptr_t)disp->FunctionEntry->BeginAddress + disp->ImageBase;
453 _LIBUNWIND_TRACE_API("_Unwind_GetRegionStart(context=%p) => 0x%" PRIxPTR,
454 (void *)context, result);
455 return result;
456}
457
458static int __unw_init_seh(unw_cursor_t *cursor, CONTEXT *context) {
459#ifdef _LIBUNWIND_TARGET_X86_64
460 new (reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_x86_64> *>(cursor))
461 UnwindCursor<LocalAddressSpace, Registers_x86_64>(
462 context, LocalAddressSpace::sThisAddressSpace);
463 auto *co = reinterpret_cast<AbstractUnwindCursor *>(cursor);
464 co->setInfoBasedOnIPRegister();
465 return UNW_ESUCCESS;
466#elif defined(_LIBUNWIND_TARGET_ARM)
467 new (reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm> *>(cursor))
468 UnwindCursor<LocalAddressSpace, Registers_arm>(
469 context, LocalAddressSpace::sThisAddressSpace);
470 auto *co = reinterpret_cast<AbstractUnwindCursor *>(cursor);
471 co->setInfoBasedOnIPRegister();
472 return UNW_ESUCCESS;
473#elif defined(_LIBUNWIND_TARGET_AARCH64)
474 new (reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm64> *>(cursor))
475 UnwindCursor<LocalAddressSpace, Registers_arm64>(
476 context, LocalAddressSpace::sThisAddressSpace);
477 auto *co = reinterpret_cast<AbstractUnwindCursor *>(cursor);
478 co->setInfoBasedOnIPRegister();
479 return UNW_ESUCCESS;
480#else
481 return UNW_EINVAL;
482#endif
483}
484
485static DISPATCHER_CONTEXT *__unw_seh_get_disp_ctx(unw_cursor_t *cursor) {
486#ifdef _LIBUNWIND_TARGET_X86_64
487 return reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_x86_64> *>(cursor)->getDispatcherContext();
488#elif defined(_LIBUNWIND_TARGET_ARM)
489 return reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm> *>(cursor)->getDispatcherContext();
490#elif defined(_LIBUNWIND_TARGET_AARCH64)
491 return reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm64> *>(cursor)->getDispatcherContext();
492#else
493 return nullptr;
494#endif
495}
496
497static void __unw_seh_set_disp_ctx(unw_cursor_t *cursor,
498 DISPATCHER_CONTEXT *disp) {
499#ifdef _LIBUNWIND_TARGET_X86_64
500 reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_x86_64> *>(cursor)->setDispatcherContext(disp);
501#elif defined(_LIBUNWIND_TARGET_ARM)
502 reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm> *>(cursor)->setDispatcherContext(disp);
503#elif defined(_LIBUNWIND_TARGET_AARCH64)
504 reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm64> *>(cursor)->setDispatcherContext(disp);
505#endif
506}
507
508#endif // defined(_LIBUNWIND_SUPPORT_SEH_UNWIND)
509