--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libunwind/src/Unwind-sjlj.c	Thu Feb 13 15:10:13 2020 +0900
@@ -0,0 +1,516 @@
+//===--------------------------- Unwind-sjlj.c ----------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//
+//  Implements setjump-longjump based C++ exceptions
+//
+//===----------------------------------------------------------------------===//
+
+#include <unwind.h>
+
+#include <inttypes.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdlib.h>
+
+#include "config.h"
+
+/// With SJLJ based exceptions, any function that has a catch clause or needs to
+/// do any clean up when an exception propagates through it, needs to call
+/// \c _Unwind_SjLj_Register at the start of the function and
+/// \c _Unwind_SjLj_Unregister at the end.  The register function is called with
+/// the address of a block of memory in the function's stack frame.  The runtime
+/// keeps a linked list (stack) of these blocks - one per thread.  The calling
+/// function also sets the personality and lsda fields of the block.
+
+#if defined(_LIBUNWIND_BUILD_SJLJ_APIS)
+
+struct _Unwind_FunctionContext {
+  // next function in stack of handlers
+  struct _Unwind_FunctionContext *prev;
+
+  // set by calling function before registering to be the landing pad
+  uint32_t                        resumeLocation;
+
+  // set by personality handler to be parameters passed to landing pad function
+  uint32_t                        resumeParameters[4];
+
+  // set by calling function before registering
+  _Unwind_Personality_Fn personality;          // arm offset=24
+  uintptr_t                       lsda;        // arm offset=28
+
+  // variable length array, contains registers to restore
+  // 0 = r7, 1 = pc, 2 = sp
+  void                           *jbuf[];
+};
+
+#if defined(_LIBUNWIND_HAS_NO_THREADS)
+# define _LIBUNWIND_THREAD_LOCAL
+#else
+# if __STDC_VERSION__ >= 201112L
+#  define _LIBUNWIND_THREAD_LOCAL _Thread_local
+# elif defined(_MSC_VER)
+#  define _LIBUNWIND_THREAD_LOCAL __declspec(thread)
+# elif defined(__GNUC__) || defined(__clang__)
+#  define _LIBUNWIND_THREAD_LOCAL __thread
+# else
+#  error Unable to create thread local storage
+# endif
+#endif
+
+
+#if !defined(FOR_DYLD)
+
+#if defined(__APPLE__)
+#include <System/pthread_machdep.h>
+#else
+static _LIBUNWIND_THREAD_LOCAL struct _Unwind_FunctionContext *stack = NULL;
+#endif
+
+static struct _Unwind_FunctionContext *__Unwind_SjLj_GetTopOfFunctionStack() {
+#if defined(__APPLE__)
+  return _pthread_getspecific_direct(__PTK_LIBC_DYLD_Unwind_SjLj_Key);
+#else
+  return stack;
+#endif
+}
+
+static void
+__Unwind_SjLj_SetTopOfFunctionStack(struct _Unwind_FunctionContext *fc) {
+#if defined(__APPLE__)
+  _pthread_setspecific_direct(__PTK_LIBC_DYLD_Unwind_SjLj_Key, fc);
+#else
+  stack = fc;
+#endif
+}
+
+#endif
+
+
+/// Called at start of each function that catches exceptions
+_LIBUNWIND_EXPORT void
+_Unwind_SjLj_Register(struct _Unwind_FunctionContext *fc) {
+  fc->prev = __Unwind_SjLj_GetTopOfFunctionStack();
+  __Unwind_SjLj_SetTopOfFunctionStack(fc);
+}
+
+
+/// Called at end of each function that catches exceptions
+_LIBUNWIND_EXPORT void
+_Unwind_SjLj_Unregister(struct _Unwind_FunctionContext *fc) {
+  __Unwind_SjLj_SetTopOfFunctionStack(fc->prev);
+}
+
+
+static _Unwind_Reason_Code
+unwind_phase1(struct _Unwind_Exception *exception_object) {
+  _Unwind_FunctionContext_t c = __Unwind_SjLj_GetTopOfFunctionStack();
+  _LIBUNWIND_TRACE_UNWINDING("unwind_phase1: initial function-context=%p",
+                             (void *)c);
+
+  // walk each frame looking for a place to stop
+  for (bool handlerNotFound = true; handlerNotFound; c = c->prev) {
+
+    // check for no more frames
+    if (c == NULL) {
+      _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): reached "
+                                 "bottom => _URC_END_OF_STACK",
+                                 (void *)exception_object);
+      return _URC_END_OF_STACK;
+    }
+
+    _LIBUNWIND_TRACE_UNWINDING("unwind_phase1: function-context=%p", (void *)c);
+    // if there is a personality routine, ask it if it will want to stop at this
+    // frame
+    if (c->personality != NULL) {
+      _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): calling "
+                                 "personality function %p",
+                                 (void *)exception_object,
+                                 (void *)c->personality);
+      _Unwind_Reason_Code personalityResult = (*c->personality)(
+          1, _UA_SEARCH_PHASE, exception_object->exception_class,
+          exception_object, (struct _Unwind_Context *)c);
+      switch (personalityResult) {
+      case _URC_HANDLER_FOUND:
+        // found a catch clause or locals that need destructing in this frame
+        // stop search and remember function context
+        handlerNotFound = false;
+        exception_object->private_2 = (uintptr_t) c;
+        _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): "
+                                   "_URC_HANDLER_FOUND",
+                                   (void *)exception_object);
+        return _URC_NO_REASON;
+
+      case _URC_CONTINUE_UNWIND:
+        _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): "
+                                   "_URC_CONTINUE_UNWIND",
+                                   (void *)exception_object);
+        // continue unwinding
+        break;
+
+      default:
+        // something went wrong
+        _LIBUNWIND_TRACE_UNWINDING(
+            "unwind_phase1(ex_ojb=%p): _URC_FATAL_PHASE1_ERROR",
+            (void *)exception_object);
+        return _URC_FATAL_PHASE1_ERROR;
+      }
+    }
+  }
+  return _URC_NO_REASON;
+}
+
+
+static _Unwind_Reason_Code
+unwind_phase2(struct _Unwind_Exception *exception_object) {
+  _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p)",
+                             (void *)exception_object);
+
+  // walk each frame until we reach where search phase said to stop
+  _Unwind_FunctionContext_t c = __Unwind_SjLj_GetTopOfFunctionStack();
+  while (true) {
+    _LIBUNWIND_TRACE_UNWINDING("unwind_phase2s(ex_ojb=%p): context=%p",
+                               (void *)exception_object, (void *)c);
+
+    // check for no more frames
+    if (c == NULL) {
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase2(ex_ojb=%p): __unw_step() reached "
+          "bottom => _URC_END_OF_STACK",
+          (void *)exception_object);
+      return _URC_END_OF_STACK;
+    }
+
+    // if there is a personality routine, tell it we are unwinding
+    if (c->personality != NULL) {
+      _Unwind_Action action = _UA_CLEANUP_PHASE;
+      if ((uintptr_t) c == exception_object->private_2)
+        action = (_Unwind_Action)(
+            _UA_CLEANUP_PHASE |
+            _UA_HANDLER_FRAME); // tell personality this was the frame it marked
+                                // in phase 1
+      _Unwind_Reason_Code personalityResult =
+          (*c->personality)(1, action, exception_object->exception_class,
+                            exception_object, (struct _Unwind_Context *)c);
+      switch (personalityResult) {
+      case _URC_CONTINUE_UNWIND:
+        // continue unwinding
+        _LIBUNWIND_TRACE_UNWINDING(
+            "unwind_phase2(ex_ojb=%p): _URC_CONTINUE_UNWIND",
+            (void *)exception_object);
+        if ((uintptr_t) c == exception_object->private_2) {
+          // phase 1 said we would stop at this frame, but we did not...
+          _LIBUNWIND_ABORT("during phase1 personality function said it would "
+                           "stop here, but now if phase2 it did not stop here");
+        }
+        break;
+      case _URC_INSTALL_CONTEXT:
+        _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): "
+                                   "_URC_INSTALL_CONTEXT, will resume at "
+                                   "landing pad %p",
+                                   (void *)exception_object, c->jbuf[1]);
+        // personality routine says to transfer control to landing pad
+        // we may get control back if landing pad calls _Unwind_Resume()
+        __Unwind_SjLj_SetTopOfFunctionStack(c);
+        __builtin_longjmp(c->jbuf, 1);
+        // __unw_resume() only returns if there was an error
+        return _URC_FATAL_PHASE2_ERROR;
+      default:
+        // something went wrong
+        _LIBUNWIND_DEBUG_LOG("personality function returned unknown result %d",
+                      personalityResult);
+        return _URC_FATAL_PHASE2_ERROR;
+      }
+    }
+    c = c->prev;
+  }
+
+  // clean up phase did not resume at the frame that the search phase said it
+  // would
+  return _URC_FATAL_PHASE2_ERROR;
+}
+
+
+static _Unwind_Reason_Code
+unwind_phase2_forced(struct _Unwind_Exception *exception_object,
+                     _Unwind_Stop_Fn stop, void *stop_parameter) {
+  // walk each frame until we reach where search phase said to stop
+  _Unwind_FunctionContext_t c = __Unwind_SjLj_GetTopOfFunctionStack();
+  while (true) {
+
+    // get next frame (skip over first which is _Unwind_RaiseException)
+    if (c == NULL) {
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase2(ex_ojb=%p): __unw_step() reached "
+          "bottom => _URC_END_OF_STACK",
+          (void *)exception_object);
+      return _URC_END_OF_STACK;
+    }
+
+    // call stop function at each frame
+    _Unwind_Action action =
+        (_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE);
+    _Unwind_Reason_Code stopResult =
+        (*stop)(1, action, exception_object->exception_class, exception_object,
+                (struct _Unwind_Context *)c, stop_parameter);
+    _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
+                               "stop function returned %d",
+                               (void *)exception_object, stopResult);
+    if (stopResult != _URC_NO_REASON) {
+      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
+                                 "stopped by stop function",
+                                 (void *)exception_object);
+      return _URC_FATAL_PHASE2_ERROR;
+    }
+
+    // if there is a personality routine, tell it we are unwinding
+    if (c->personality != NULL) {
+      _Unwind_Personality_Fn p = (_Unwind_Personality_Fn)c->personality;
+      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
+                                 "calling personality function %p",
+                                 (void *)exception_object, (void *)p);
+      _Unwind_Reason_Code personalityResult =
+          (*p)(1, action, exception_object->exception_class, exception_object,
+               (struct _Unwind_Context *)c);
+      switch (personalityResult) {
+      case _URC_CONTINUE_UNWIND:
+        _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p):  "
+                                   "personality returned _URC_CONTINUE_UNWIND",
+                                   (void *)exception_object);
+        // destructors called, continue unwinding
+        break;
+      case _URC_INSTALL_CONTEXT:
+        _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
+                                   "personality returned _URC_INSTALL_CONTEXT",
+                                   (void *)exception_object);
+        // we may get control back if landing pad calls _Unwind_Resume()
+        __Unwind_SjLj_SetTopOfFunctionStack(c);
+        __builtin_longjmp(c->jbuf, 1);
+        break;
+      default:
+        // something went wrong
+        _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
+                                   "personality returned %d, "
+                                   "_URC_FATAL_PHASE2_ERROR",
+                                   (void *)exception_object, personalityResult);
+        return _URC_FATAL_PHASE2_ERROR;
+      }
+    }
+    c = c->prev;
+  }
+
+  // call stop function one last time and tell it we've reached the end of the
+  // stack
+  _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): calling stop "
+                             "function with _UA_END_OF_STACK",
+                             (void *)exception_object);
+  _Unwind_Action lastAction =
+      (_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE | _UA_END_OF_STACK);
+  (*stop)(1, lastAction, exception_object->exception_class, exception_object,
+          (struct _Unwind_Context *)c, stop_parameter);
+
+  // clean up phase did not resume at the frame that the search phase said it
+  // would
+  return _URC_FATAL_PHASE2_ERROR;
+}
+
+
+/// Called by __cxa_throw.  Only returns if there is a fatal error
+_LIBUNWIND_EXPORT _Unwind_Reason_Code
+_Unwind_SjLj_RaiseException(struct _Unwind_Exception *exception_object) {
+  _LIBUNWIND_TRACE_API("_Unwind_SjLj_RaiseException(ex_obj=%p)",
+                       (void *)exception_object);
+
+  // mark that this is a non-forced unwind, so _Unwind_Resume() can do the right
+  // thing
+  exception_object->private_1 = 0;
+  exception_object->private_2 = 0;
+
+  // phase 1: the search phase
+  _Unwind_Reason_Code phase1 = unwind_phase1(exception_object);
+  if (phase1 != _URC_NO_REASON)
+    return phase1;
+
+  // phase 2: the clean up phase
+  return unwind_phase2(exception_object);
+}
+
+
+
+/// When _Unwind_RaiseException() is in phase2, it hands control
+/// to the personality function at each frame.  The personality
+/// may force a jump to a landing pad in that function, the landing
+/// pad code may then call _Unwind_Resume() to continue with the
+/// unwinding.  Note: the call to _Unwind_Resume() is from compiler
+/// geneated user code.  All other _Unwind_* routines are called
+/// by the C++ runtime __cxa_* routines.
+///
+/// Re-throwing an exception is implemented by having the code call
+/// __cxa_rethrow() which in turn calls _Unwind_Resume_or_Rethrow()
+_LIBUNWIND_EXPORT void
+_Unwind_SjLj_Resume(struct _Unwind_Exception *exception_object) {
+  _LIBUNWIND_TRACE_API("_Unwind_SjLj_Resume(ex_obj=%p)",
+                       (void *)exception_object);
+
+  if (exception_object->private_1 != 0)
+    unwind_phase2_forced(exception_object,
+                         (_Unwind_Stop_Fn) exception_object->private_1,
+                         (void *)exception_object->private_2);
+  else
+    unwind_phase2(exception_object);
+
+  // clients assume _Unwind_Resume() does not return, so all we can do is abort.
+  _LIBUNWIND_ABORT("_Unwind_SjLj_Resume() can't return");
+}
+
+
+///  Called by __cxa_rethrow().
+_LIBUNWIND_EXPORT _Unwind_Reason_Code
+_Unwind_SjLj_Resume_or_Rethrow(struct _Unwind_Exception *exception_object) {
+  _LIBUNWIND_TRACE_API("__Unwind_SjLj_Resume_or_Rethrow(ex_obj=%p), "
+                       "private_1=%" PRIuPTR,
+                       (void *)exception_object, exception_object->private_1);
+  // If this is non-forced and a stopping place was found, then this is a
+  // re-throw.
+  // Call _Unwind_RaiseException() as if this was a new exception.
+  if (exception_object->private_1 == 0) {
+    return _Unwind_SjLj_RaiseException(exception_object);
+    // should return if there is no catch clause, so that __cxa_rethrow can call
+    // std::terminate()
+  }
+
+  // Call through to _Unwind_Resume() which distiguishes between forced and
+  // regular exceptions.
+  _Unwind_SjLj_Resume(exception_object);
+  _LIBUNWIND_ABORT("__Unwind_SjLj_Resume_or_Rethrow() called "
+                    "_Unwind_SjLj_Resume() which unexpectedly returned");
+}
+
+
+/// Called by personality handler during phase 2 to get LSDA for current frame.
+_LIBUNWIND_EXPORT uintptr_t
+_Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) {
+  _Unwind_FunctionContext_t ufc = (_Unwind_FunctionContext_t) context;
+  _LIBUNWIND_TRACE_API("_Unwind_GetLanguageSpecificData(context=%p) "
+                       "=> 0x%" PRIuPTR,
+                       (void *)context, ufc->lsda);
+  return ufc->lsda;
+}
+
+
+/// Called by personality handler during phase 2 to get register values.
+_LIBUNWIND_EXPORT uintptr_t _Unwind_GetGR(struct _Unwind_Context *context,
+                                          int index) {
+  _LIBUNWIND_TRACE_API("_Unwind_GetGR(context=%p, reg=%d)", (void *)context,
+                       index);
+  _Unwind_FunctionContext_t ufc = (_Unwind_FunctionContext_t) context;
+  return ufc->resumeParameters[index];
+}
+
+
+/// Called by personality handler during phase 2 to alter register values.
+_LIBUNWIND_EXPORT void _Unwind_SetGR(struct _Unwind_Context *context, int index,
+                                     uintptr_t new_value) {
+  _LIBUNWIND_TRACE_API("_Unwind_SetGR(context=%p, reg=%d, value=0x%" PRIuPTR
+                       ")",
+                       (void *)context, index, new_value);
+  _Unwind_FunctionContext_t ufc = (_Unwind_FunctionContext_t) context;
+  ufc->resumeParameters[index] = new_value;
+}
+
+
+/// Called by personality handler during phase 2 to get instruction pointer.
+_LIBUNWIND_EXPORT uintptr_t _Unwind_GetIP(struct _Unwind_Context *context) {
+  _Unwind_FunctionContext_t ufc = (_Unwind_FunctionContext_t) context;
+  _LIBUNWIND_TRACE_API("_Unwind_GetIP(context=%p) => 0x%" PRIu32,
+                       (void *)context, ufc->resumeLocation + 1);
+  return ufc->resumeLocation + 1;
+}
+
+
+/// Called by personality handler during phase 2 to get instruction pointer.
+/// ipBefore is a boolean that says if IP is already adjusted to be the call
+/// site address.  Normally IP is the return address.
+_LIBUNWIND_EXPORT uintptr_t _Unwind_GetIPInfo(struct _Unwind_Context *context,
+                                              int *ipBefore) {
+  _Unwind_FunctionContext_t ufc = (_Unwind_FunctionContext_t) context;
+  *ipBefore = 0;
+  _LIBUNWIND_TRACE_API("_Unwind_GetIPInfo(context=%p, %p) => 0x%" PRIu32,
+                       (void *)context, (void *)ipBefore,
+                       ufc->resumeLocation + 1);
+  return ufc->resumeLocation + 1;
+}
+
+
+/// Called by personality handler during phase 2 to alter instruction pointer.
+_LIBUNWIND_EXPORT void _Unwind_SetIP(struct _Unwind_Context *context,
+                                     uintptr_t new_value) {
+  _LIBUNWIND_TRACE_API("_Unwind_SetIP(context=%p, value=0x%" PRIuPTR ")",
+                       (void *)context, new_value);
+  _Unwind_FunctionContext_t ufc = (_Unwind_FunctionContext_t) context;
+  ufc->resumeLocation = new_value - 1;
+}
+
+
+/// Called by personality handler during phase 2 to find the start of the
+/// function.
+_LIBUNWIND_EXPORT uintptr_t
+_Unwind_GetRegionStart(struct _Unwind_Context *context) {
+  // Not supported or needed for sjlj based unwinding
+  (void)context;
+  _LIBUNWIND_TRACE_API("_Unwind_GetRegionStart(context=%p)", (void *)context);
+  return 0;
+}
+
+
+/// Called by personality handler during phase 2 if a foreign exception
+/// is caught.
+_LIBUNWIND_EXPORT void
+_Unwind_DeleteException(struct _Unwind_Exception *exception_object) {
+  _LIBUNWIND_TRACE_API("_Unwind_DeleteException(ex_obj=%p)",
+                       (void *)exception_object);
+  if (exception_object->exception_cleanup != NULL)
+    (*exception_object->exception_cleanup)(_URC_FOREIGN_EXCEPTION_CAUGHT,
+                                           exception_object);
+}
+
+
+
+/// Called by personality handler during phase 2 to get base address for data
+/// relative encodings.
+_LIBUNWIND_EXPORT uintptr_t
+_Unwind_GetDataRelBase(struct _Unwind_Context *context) {
+  // Not supported or needed for sjlj based unwinding
+  (void)context;
+  _LIBUNWIND_TRACE_API("_Unwind_GetDataRelBase(context=%p)", (void *)context);
+  _LIBUNWIND_ABORT("_Unwind_GetDataRelBase() not implemented");
+}
+
+
+/// Called by personality handler during phase 2 to get base address for text
+/// relative encodings.
+_LIBUNWIND_EXPORT uintptr_t
+_Unwind_GetTextRelBase(struct _Unwind_Context *context) {
+  // Not supported or needed for sjlj based unwinding
+  (void)context;
+  _LIBUNWIND_TRACE_API("_Unwind_GetTextRelBase(context=%p)", (void *)context);
+  _LIBUNWIND_ABORT("_Unwind_GetTextRelBase() not implemented");
+}
+
+
+/// Called by personality handler to get "Call Frame Area" for current frame.
+_LIBUNWIND_EXPORT uintptr_t _Unwind_GetCFA(struct _Unwind_Context *context) {
+  _LIBUNWIND_TRACE_API("_Unwind_GetCFA(context=%p)", (void *)context);
+  if (context != NULL) {
+    _Unwind_FunctionContext_t ufc = (_Unwind_FunctionContext_t) context;
+    // Setjmp/longjmp based exceptions don't have a true CFA.
+    // Instead, the SP in the jmpbuf is the closest approximation.
+    return (uintptr_t) ufc->jbuf[2];
+  }
+  return 0;
+}
+
+#endif // defined(_LIBUNWIND_BUILD_SJLJ_APIS)