Vendor import of stripped LLVM libunwind trunk r366426 (just before thevendor/llvm-libunwind/libunwind-trunk-r366426vendor/llvm-libunwind/libunwind-release_900-r372316vendor/llvm-libunwind/libunwind-release_90-r371301vendor/llvm-libunwind/libunwind-release_90-r370514vendor/llvm-libunwind/libunwind-release_90-r369369vendor/llvm-libunwind-90

release_90 branch point):

https://llvm.org/svn/llvm-project/libunwind/trunk@366426

27 files changed, 1181 insertions, 973 deletions

diff --git a/LICENSE.TXT b/LICENSE.TXT
index 23109b4aa7bb..1e3120621cae 100644
--- a/LICENSE.TXT
+++ b/LICENSE.TXT
@@ -1,5 +1,240 @@
 ==============================================================================
-libunwind License
+The LLVM Project is under the Apache License v2.0 with LLVM Exceptions:
+==============================================================================
+
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+1) It will be in a separate directory tree with its own `LICENSE.txt` or
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+==============================================================================
+Legacy LLVM License (https://llvm.org/docs/DeveloperPolicy.html#legacy):
 ==============================================================================
 
 The libunwind library is dual licensed under both the University of Illinois
diff --git a/include/__libunwind_config.h b/include/__libunwind_config.h
index a8e30de13a6a..6e7e5e6f7f86 100644
--- a/include/__libunwind_config.h
+++ b/include/__libunwind_config.h
@@ -1,9 +1,8 @@
 //===------------------------- __libunwind_config.h -----------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //===----------------------------------------------------------------------===//
 
diff --git a/include/libunwind.h b/include/libunwind.h
index 29c4aebde5ac..d06724d3c31f 100644
--- a/include/libunwind.h
+++ b/include/libunwind.h
@@ -1,9 +1,8 @@
 //===---------------------------- libunwind.h -----------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 // Compatible with libunwind API documented at:
@@ -76,7 +75,7 @@ typedef struct unw_addr_space *unw_addr_space_t;
 
 typedef int unw_regnum_t;
 typedef uintptr_t unw_word_t;
-#if defined(__arm__)
+#if defined(__arm__) && !defined(__ARM_DWARF_EH__)
 typedef uint64_t unw_fpreg_t;
 #else
 typedef double unw_fpreg_t;
@@ -125,32 +124,6 @@ extern int unw_get_proc_name(unw_cursor_t *, char *, size_t, unw_word_t *) LIBUN
 
 extern unw_addr_space_t unw_local_addr_space;
 
-#ifdef UNW_REMOTE
-/*
- * Mac OS X "remote" API for unwinding other processes on same machine
- *
- */
-extern unw_addr_space_t unw_create_addr_space_for_task(task_t);
-extern void unw_destroy_addr_space(unw_addr_space_t);
-extern int unw_init_remote_thread(unw_cursor_t *, unw_addr_space_t, thread_t *);
-#endif /* UNW_REMOTE */
-
-/*
- * traditional libunwind "remote" API
- *   NOT IMPLEMENTED on Mac OS X
- *
- * extern int               unw_init_remote(unw_cursor_t*, unw_addr_space_t,
- *                                          thread_t*);
- * extern unw_accessors_t   unw_get_accessors(unw_addr_space_t);
- * extern unw_addr_space_t  unw_create_addr_space(unw_accessors_t, int);
- * extern void              unw_flush_cache(unw_addr_space_t, unw_word_t,
- *                                          unw_word_t);
- * extern int               unw_set_caching_policy(unw_addr_space_t,
- *                                                 unw_caching_policy_t);
- * extern void              _U_dyn_register(unw_dyn_info_t*);
- * extern void              _U_dyn_cancel(unw_dyn_info_t*);
- */
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/include/mach-o/compact_unwind_encoding.h b/include/mach-o/compact_unwind_encoding.h
index de14fd51e53e..5301b1055ef9 100644
--- a/include/mach-o/compact_unwind_encoding.h
+++ b/include/mach-o/compact_unwind_encoding.h
@@ -1,9 +1,8 @@
 //===------------------ mach-o/compact_unwind_encoding.h ------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 // Darwin's alternative to DWARF based unwind encodings.
diff --git a/include/unwind.h b/include/unwind.h
index ae8ae5d24edc..b6cc70498b37 100644
--- a/include/unwind.h
+++ b/include/unwind.h
@@ -1,13 +1,12 @@
 //===------------------------------- unwind.h -----------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 // C++ ABI Level 1 ABI documented at:
-//   http://mentorembedded.github.io/cxx-abi/abi-eh.html
+//   https://itanium-cxx-abi.github.io/cxx-abi/abi-eh.html
 //
 //===----------------------------------------------------------------------===//
 
diff --git a/src/AddressSpace.hpp b/src/AddressSpace.hpp
index 30ad35995aec..fb07c807db9e 100644
--- a/src/AddressSpace.hpp
+++ b/src/AddressSpace.hpp
@@ -1,9 +1,8 @@
 //===------------------------- AddressSpace.hpp ---------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 // Abstracts accessing local vs remote address spaces.
@@ -28,6 +27,9 @@
 
 #if _LIBUNWIND_USE_DLADDR
 #include <dlfcn.h>
+#if defined(__unix__) &&  defined(__ELF__) && defined(_LIBUNWIND_HAS_COMMENT_LIB_PRAGMA)
+#pragma comment(lib, "dl")
+#endif
 #endif
 
 #ifdef __APPLE__
@@ -457,6 +459,8 @@ inline bool LocalAddressSpace::findUnwindSections(pint_t targetAddr,
 #elif defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) && defined(_WIN32)
   // Don't even bother, since Windows has functions that do all this stuff
   // for us.
+  (void)targetAddr;
+  (void)info;
   return true;
 #elif defined(_LIBUNWIND_ARM_EHABI) && defined(__BIONIC__) &&                  \
     (__ANDROID_API__ < 21)
@@ -534,11 +538,11 @@ inline bool LocalAddressSpace::findUnwindSections(pint_t targetAddr,
 #endif
             cbdata->sects->dwarf_index_section = eh_frame_hdr_start;
             cbdata->sects->dwarf_index_section_length = phdr->p_memsz;
-            EHHeaderParser<LocalAddressSpace>::decodeEHHdr(
+            found_hdr = EHHeaderParser<LocalAddressSpace>::decodeEHHdr(
                 *cbdata->addressSpace, eh_frame_hdr_start, phdr->p_memsz,
                 hdrInfo);
-            cbdata->sects->dwarf_section = hdrInfo.eh_frame_ptr;
-            found_hdr = true;
+            if (found_hdr)
+              cbdata->sects->dwarf_section = hdrInfo.eh_frame_ptr;
           }
         }
 
@@ -597,142 +601,15 @@ inline bool LocalAddressSpace::findFunctionName(pint_t addr, char *buf,
       return true;
     }
   }
+#else
+  (void)addr;
+  (void)buf;
+  (void)bufLen;
+  (void)offset;
 #endif
   return false;
 }
 
-
-
-#ifdef UNW_REMOTE
-
-/// RemoteAddressSpace is used as a template parameter to UnwindCursor when
-/// unwinding a thread in the another process.  The other process can be a
-/// different endianness and a different pointer size which is handled by
-/// the P template parameter.
-template <typename P>
-class RemoteAddressSpace {
-public:
-  RemoteAddressSpace(task_t task) : fTask(task) {}
-
-  typedef typename P::uint_t pint_t;
-
-  uint8_t   get8(pint_t addr);
-  uint16_t  get16(pint_t addr);
-  uint32_t  get32(pint_t addr);
-  uint64_t  get64(pint_t addr);
-  pint_t    getP(pint_t addr);
-  uint64_t  getRegister(pint_t addr);
-  uint64_t  getULEB128(pint_t &addr, pint_t end);
-  int64_t   getSLEB128(pint_t &addr, pint_t end);
-  pint_t    getEncodedP(pint_t &addr, pint_t end, uint8_t encoding,
-                        pint_t datarelBase = 0);
-  bool      findFunctionName(pint_t addr, char *buf, size_t bufLen,
-                        unw_word_t *offset);
-  bool      findUnwindSections(pint_t targetAddr, UnwindInfoSections &info);
-  bool      findOtherFDE(pint_t targetAddr, pint_t &fde);
-private:
-  void *localCopy(pint_t addr);
-
-  task_t fTask;
-};
-
-template <typename P> uint8_t RemoteAddressSpace<P>::get8(pint_t addr) {
-  return *((uint8_t *)localCopy(addr));
-}
-
-template <typename P> uint16_t RemoteAddressSpace<P>::get16(pint_t addr) {
-  return P::E::get16(*(uint16_t *)localCopy(addr));
-}
-
-template <typename P> uint32_t RemoteAddressSpace<P>::get32(pint_t addr) {
-  return P::E::get32(*(uint32_t *)localCopy(addr));
-}
-
-template <typename P> uint64_t RemoteAddressSpace<P>::get64(pint_t addr) {
-  return P::E::get64(*(uint64_t *)localCopy(addr));
-}
-
-template <typename P>
-typename P::uint_t RemoteAddressSpace<P>::getP(pint_t addr) {
-  return P::getP(*(uint64_t *)localCopy(addr));
-}
-
-template <typename P>
-typename P::uint_t OtherAddressSpace<P>::getRegister(pint_t addr) {
-  return P::getRegister(*(uint64_t *)localCopy(addr));
-}
-
-template <typename P>
-uint64_t OtherAddressSpace<P>::getULEB128(pint_t &addr, pint_t end) {
-  uintptr_t size = (end - addr);
-  LocalAddressSpace::pint_t laddr = (LocalAddressSpace::pint_t) localCopy(addr);
-  LocalAddressSpace::pint_t sladdr = laddr;
-  uint64_t result = LocalAddressSpace::getULEB128(laddr, laddr + size);
-  addr += (laddr - sladdr);
-  return result;
-}
-
-template <typename P>
-int64_t RemoteAddressSpace<P>::getSLEB128(pint_t &addr, pint_t end) {
-  uintptr_t size = (end - addr);
-  LocalAddressSpace::pint_t laddr = (LocalAddressSpace::pint_t) localCopy(addr);
-  LocalAddressSpace::pint_t sladdr = laddr;
-  uint64_t result = LocalAddressSpace::getSLEB128(laddr, laddr + size);
-  addr += (laddr - sladdr);
-  return result;
-}
-
-template <typename P> void *RemoteAddressSpace<P>::localCopy(pint_t addr) {
-  // FIX ME
-}
-
-template <typename P>
-bool RemoteAddressSpace<P>::findFunctionName(pint_t addr, char *buf,
-                                             size_t bufLen,
-                                             unw_word_t *offset) {
-  // FIX ME
-}
-
-/// unw_addr_space is the base class that abstract unw_addr_space_t type in
-/// libunwind.h points to.
-struct unw_addr_space {
-  cpu_type_t cpuType;
-  task_t taskPort;
-};
-
-/// unw_addr_space_i386 is the concrete instance that a unw_addr_space_t points
-/// to when examining
-/// a 32-bit intel process.
-struct unw_addr_space_i386 : public unw_addr_space {
-  unw_addr_space_i386(task_t task) : oas(task) {}
-  RemoteAddressSpace<Pointer32<LittleEndian>> oas;
-};
-
-/// unw_addr_space_x86_64 is the concrete instance that a unw_addr_space_t
-/// points to when examining
-/// a 64-bit intel process.
-struct unw_addr_space_x86_64 : public unw_addr_space {
-  unw_addr_space_x86_64(task_t task) : oas(task) {}
-  RemoteAddressSpace<Pointer64<LittleEndian>> oas;
-};
-
-/// unw_addr_space_ppc is the concrete instance that a unw_addr_space_t points
-/// to when examining
-/// a 32-bit PowerPC process.
-struct unw_addr_space_ppc : public unw_addr_space {
-  unw_addr_space_ppc(task_t task) : oas(task) {}
-  RemoteAddressSpace<Pointer32<BigEndian>> oas;
-};
-
-/// unw_addr_space_ppc is the concrete instance that a unw_addr_space_t points
-/// to when examining a 64-bit PowerPC process.
-struct unw_addr_space_ppc64 : public unw_addr_space {
-  unw_addr_space_ppc64(task_t task) : oas(task) {}
-  RemoteAddressSpace<Pointer64<LittleEndian>> oas;
-};
-
-#endif // UNW_REMOTE
-
 } // namespace libunwind
 
 #endif // __ADDRESSSPACE_HPP__
diff --git a/src/CompactUnwinder.hpp b/src/CompactUnwinder.hpp
index 7b97bf84cebd..1c3175dff50a 100644
--- a/src/CompactUnwinder.hpp
+++ b/src/CompactUnwinder.hpp
@@ -1,9 +1,8 @@
 //===-------------------------- CompactUnwinder.hpp -----------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 //  Does runtime stack unwinding using compact unwind encodings.
diff --git a/src/DwarfInstructions.hpp b/src/DwarfInstructions.hpp
index ec70c0a11f70..29a070fa3e04 100644
--- a/src/DwarfInstructions.hpp
+++ b/src/DwarfInstructions.hpp
@@ -1,9 +1,8 @@
 //===-------------------------- DwarfInstructions.hpp ---------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 //  Processor specific interpretation of DWARF unwind info.
@@ -82,12 +81,11 @@ typename A::pint_t DwarfInstructions<A, R>::getSavedRegister(
     const RegisterLocation &savedReg) {
   switch (savedReg.location) {
   case CFI_Parser<A>::kRegisterInCFA:
-    return addressSpace.getRegister(cfa + (pint_t)savedReg.value);
+    return (pint_t)addressSpace.getRegister(cfa + (pint_t)savedReg.value);
 
   case CFI_Parser<A>::kRegisterAtExpression:
-    return addressSpace.getRegister(
-        evaluateExpression((pint_t)savedReg.value, addressSpace,
-                            registers, cfa));
+    return (pint_t)addressSpace.getRegister(evaluateExpression(
+        (pint_t)savedReg.value, addressSpace, registers, cfa));
 
   case CFI_Parser<A>::kRegisterIsExpression:
     return evaluateExpression((pint_t)savedReg.value, addressSpace,
@@ -234,6 +232,31 @@ int DwarfInstructions<A, R>::stepWithDwarf(A &addressSpace, pint_t pc,
       }
 #endif
 
+#if defined(_LIBUNWIND_TARGET_PPC64)
+#define PPC64_ELFV1_R2_LOAD_INST_ENCODING 0xe8410028u // ld r2,40(r1)
+#define PPC64_ELFV1_R2_OFFSET 40
+#define PPC64_ELFV2_R2_LOAD_INST_ENCODING 0xe8410018u // ld r2,24(r1)
+#define PPC64_ELFV2_R2_OFFSET 24
+      // If the instruction at return address is a TOC (r2) restore,
+      // then r2 was saved and needs to be restored.
+      // ELFv2 ABI specifies that the TOC Pointer must be saved at SP + 24,
+      // while in ELFv1 ABI it is saved at SP + 40.
+      if (R::getArch() == REGISTERS_PPC64 && returnAddress != 0) {
+        pint_t sp = newRegisters.getRegister(UNW_REG_SP);
+        pint_t r2 = 0;
+        switch (addressSpace.get32(returnAddress)) {
+        case PPC64_ELFV1_R2_LOAD_INST_ENCODING:
+          r2 = addressSpace.get64(sp + PPC64_ELFV1_R2_OFFSET);
+          break;
+        case PPC64_ELFV2_R2_LOAD_INST_ENCODING:
+          r2 = addressSpace.get64(sp + PPC64_ELFV2_R2_OFFSET);
+          break;
+        }
+        if (r2)
+          newRegisters.setRegister(UNW_PPC64_R2, r2);
+      }
+#endif
+
       // Return address is address after call site instruction, so setting IP to
       // that does simualates a return.
       newRegisters.setIP(returnAddress);
diff --git a/src/DwarfParser.hpp b/src/DwarfParser.hpp
index a2c6d7f8db9f..df69c2a4bd23 100644
--- a/src/DwarfParser.hpp
+++ b/src/DwarfParser.hpp
@@ -1,9 +1,8 @@
 //===--------------------------- DwarfParser.hpp --------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 //  Parses DWARF CFIs (FDEs and CIEs).
diff --git a/src/EHHeaderParser.hpp b/src/EHHeaderParser.hpp
index 9bdaf5505ff0..0101835b8e63 100644
--- a/src/EHHeaderParser.hpp
+++ b/src/EHHeaderParser.hpp
@@ -1,9 +1,8 @@
 //===------------------------- EHHeaderParser.hpp -------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 //  Parses ELF .eh_frame_hdr sections.
@@ -36,7 +35,7 @@ public:
     uint8_t table_enc;
   };
 
-  static void decodeEHHdr(A &addressSpace, pint_t ehHdrStart, pint_t ehHdrEnd,
+  static bool decodeEHHdr(A &addressSpace, pint_t ehHdrStart, pint_t ehHdrEnd,
                           EHHeaderInfo &ehHdrInfo);
   static bool findFDE(A &addressSpace, pint_t pc, pint_t ehHdrStart,
                       uint32_t sectionLength,
@@ -53,12 +52,14 @@ private:
 };
 
 template <typename A>
-void EHHeaderParser<A>::decodeEHHdr(A &addressSpace, pint_t ehHdrStart,
+bool EHHeaderParser<A>::decodeEHHdr(A &addressSpace, pint_t ehHdrStart,
                                     pint_t ehHdrEnd, EHHeaderInfo &ehHdrInfo) {
   pint_t p = ehHdrStart;
   uint8_t version = addressSpace.get8(p++);
-  if (version != 1)
-    _LIBUNWIND_ABORT("Unsupported .eh_frame_hdr version");
+  if (version != 1) {
+    _LIBUNWIND_LOG0("Unsupported .eh_frame_hdr version");
+    return false;
+  }
 
   uint8_t eh_frame_ptr_enc = addressSpace.get8(p++);
   uint8_t fde_count_enc = addressSpace.get8(p++);
@@ -71,6 +72,8 @@ void EHHeaderParser<A>::decodeEHHdr(A &addressSpace, pint_t ehHdrStart,
           ? 0
           : addressSpace.getEncodedP(p, ehHdrEnd, fde_count_enc, ehHdrStart);
   ehHdrInfo.table = p;
+
+  return true;
 }
 
 template <typename A>
@@ -102,7 +105,9 @@ bool EHHeaderParser<A>::findFDE(A &addressSpace, pint_t pc, pint_t ehHdrStart,
   pint_t ehHdrEnd = ehHdrStart + sectionLength;
 
   EHHeaderParser<A>::EHHeaderInfo hdrInfo;
-  EHHeaderParser<A>::decodeEHHdr(addressSpace, ehHdrStart, ehHdrEnd, hdrInfo);
+  if (!EHHeaderParser<A>::decodeEHHdr(addressSpace, ehHdrStart, ehHdrEnd,
+                                      hdrInfo))
+    return false;
 
   size_t tableEntrySize = getTableEntrySize(hdrInfo.table_enc);
   pint_t tableEntry;
diff --git a/src/RWMutex.hpp b/src/RWMutex.hpp
index 50a78a57b089..a37ac77144f3 100644
--- a/src/RWMutex.hpp
+++ b/src/RWMutex.hpp
@@ -1,9 +1,8 @@
 //===----------------------------- Registers.hpp --------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 // Abstract interface to shared reader/writer log, hiding platform and
@@ -18,6 +17,9 @@
 #include <windows.h>
 #elif !defined(_LIBUNWIND_HAS_NO_THREADS)
 #include <pthread.h>
+#if defined(__unix__) &&  defined(__ELF__) && defined(_LIBUNWIND_HAS_COMMENT_LIB_PRAGMA)
+#pragma comment(lib, "pthread")
+#endif
 #endif
 
 namespace libunwind {
@@ -57,11 +59,11 @@ private:
   SRWLOCK _lock = SRWLOCK_INIT;
 };
 
-#else
+#elif !defined(LIBUNWIND_USE_WEAK_PTHREAD)
 
 class _LIBUNWIND_HIDDEN RWMutex {
 public:
-  bool lock_shared() { return pthread_rwlock_rdlock(&_lock) == 0; }
+  bool lock_shared() { return pthread_rwlock_rdlock(&_lock) == 0;  }
   bool unlock_shared() { return pthread_rwlock_unlock(&_lock) == 0; }
   bool lock() { return pthread_rwlock_wrlock(&_lock) == 0; }
   bool unlock() { return pthread_rwlock_unlock(&_lock) == 0; }
@@ -70,6 +72,41 @@ private:
   pthread_rwlock_t _lock = PTHREAD_RWLOCK_INITIALIZER;
 };
 
+#else
+
+extern "C" int __attribute__((weak))
+pthread_create(pthread_t *thread, const pthread_attr_t *attr,
+               void *(*start_routine)(void *), void *arg);
+extern "C" int __attribute__((weak))
+pthread_rwlock_rdlock(pthread_rwlock_t *lock);
+extern "C" int __attribute__((weak))
+pthread_rwlock_wrlock(pthread_rwlock_t *lock);
+extern "C" int __attribute__((weak))
+pthread_rwlock_unlock(pthread_rwlock_t *lock);
+
+// Calls to the locking functions are gated on pthread_create, and not the
+// functions themselves, because the data structure should only be locked if
+// another thread has been created. This is what similar libraries do.
+
+class _LIBUNWIND_HIDDEN RWMutex {
+public:
+  bool lock_shared() {
+    return !pthread_create || (pthread_rwlock_rdlock(&_lock) == 0);
+  }
+  bool unlock_shared() {
+    return !pthread_create || (pthread_rwlock_unlock(&_lock) == 0);
+  }
+  bool lock() {
+    return !pthread_create || (pthread_rwlock_wrlock(&_lock) == 0);
+  }
+  bool unlock() {
+    return !pthread_create || (pthread_rwlock_unlock(&_lock) == 0);
+  }
+
+private:
+  pthread_rwlock_t _lock = PTHREAD_RWLOCK_INITIALIZER;
+};
+
 #endif
 
 } // namespace libunwind
diff --git a/src/Registers.hpp b/src/Registers.hpp
index a4f5a85f2a7b..a36c6cf90d3f 100644
--- a/src/Registers.hpp
+++ b/src/Registers.hpp
@@ -1,9 +1,8 @@
 //===----------------------------- Registers.hpp --------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 //  Models register sets for supported processors.
@@ -2104,16 +2103,16 @@ private:
     uint32_t __pc;    // Program counter r15
   };
 
-  static void saveVFPWithFSTMD(unw_fpreg_t*);
-  static void saveVFPWithFSTMX(unw_fpreg_t*);
-  static void saveVFPv3(unw_fpreg_t*);
-  static void restoreVFPWithFLDMD(unw_fpreg_t*);
-  static void restoreVFPWithFLDMX(unw_fpreg_t*);
-  static void restoreVFPv3(unw_fpreg_t*);
+  static void saveVFPWithFSTMD(void*);
+  static void saveVFPWithFSTMX(void*);
+  static void saveVFPv3(void*);
+  static void restoreVFPWithFLDMD(void*);
+  static void restoreVFPWithFLDMX(void*);
+  static void restoreVFPv3(void*);
 #if defined(__ARM_WMMX)
-  static void saveiWMMX(unw_fpreg_t*);
+  static void saveiWMMX(void*);
   static void saveiWMMXControl(uint32_t*);
-  static void restoreiWMMX(unw_fpreg_t*);
+  static void restoreiWMMX(void*);
   static void restoreiWMMXControl(uint32_t*);
 #endif
   void restoreCoreAndJumpTo();
@@ -2155,7 +2154,7 @@ inline Registers_arm::Registers_arm(const void *registers)
     _saved_vfp_d16_d31(false) {
   static_assert((check_fit<Registers_arm, unw_context_t>::does_fit),
                 "arm registers do not fit into unw_context_t");
-  // See unw_getcontext() note about data.
+  // See __unw_getcontext() note about data.
   memcpy(&_registers, registers, sizeof(_registers));
   memset(&_vfp_d0_d15_pad, 0, sizeof(_vfp_d0_d15_pad));
   memset(&_vfp_d16_d31, 0, sizeof(_vfp_d16_d31));
@@ -2434,7 +2433,7 @@ inline const char *Registers_arm::getRegisterName(int regNum) {
 
 inline bool Registers_arm::validFloatRegister(int regNum) const {
   // NOTE: Consider the intel MMX registers floating points so the
-  // unw_get_fpreg can be used to transmit the 64-bit data back.
+  // __unw_get_fpreg can be used to transmit the 64-bit data back.
   return ((regNum >= UNW_ARM_D0) && (regNum <= UNW_ARM_D31))
 #if defined(__ARM_WMMX)
       || ((regNum >= UNW_ARM_WR0) && (regNum <= UNW_ARM_WR15))
diff --git a/src/Unwind-EHABI.cpp b/src/Unwind-EHABI.cpp
index f37732c6ac86..4ff5e318b5f1 100644
--- a/src/Unwind-EHABI.cpp
+++ b/src/Unwind-EHABI.cpp
@@ -1,9 +1,8 @@
 //===--------------------------- Unwind-EHABI.cpp -------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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 ARM zero-cost C++ exceptions
@@ -21,8 +20,6 @@
 #include <stdlib.h>
 #include <string.h>
 
-#include <type_traits>
-
 #include "config.h"
 #include "libunwind.h"
 #include "libunwind_ext.h"
@@ -34,7 +31,11 @@ namespace {
 // signinficant byte.
 uint8_t getByte(const uint32_t* data, size_t offset) {
   const uint8_t* byteData = reinterpret_cast<const uint8_t*>(data);
+#ifdef __LITTLE_ENDIAN__
   return byteData[(offset & ~(size_t)0x03) + (3 - (offset & (size_t)0x03))];
+#else
+  return byteData[offset];
+#endif
 }
 
 const char* getNextWord(const char* data, uint32_t* out) {
@@ -182,7 +183,7 @@ static _Unwind_Reason_Code unwindOneFrame(_Unwind_State state,
   if (result != _URC_CONTINUE_UNWIND)
     return result;
 
-  if (unw_step(reinterpret_cast<unw_cursor_t*>(context)) != UNW_STEP_SUCCESS)
+  if (__unw_step(reinterpret_cast<unw_cursor_t *>(context)) != UNW_STEP_SUCCESS)
     return _URC_FAILURE;
   return _URC_CONTINUE_UNWIND;
 }
@@ -443,17 +444,18 @@ unwind_phase1(unw_context_t *uc, unw_cursor_t *cursor, _Unwind_Exception *except
   // In this implementation, the phases don't share the VRS backing store.
   // Instead, they are passed the original |uc| and they create a new VRS
   // from scratch thus achieving the same effect.
-  unw_init_local(cursor, uc);
+  __unw_init_local(cursor, uc);
 
   // Walk each frame looking for a place to stop.
   for (bool handlerNotFound = true; handlerNotFound;) {
 
     // See if frame has code to run (has personality routine).
     unw_proc_info_t frameInfo;
-    if (unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): unw_get_proc_info "
-                                 "failed => _URC_FATAL_PHASE1_ERROR",
-                                 static_cast<void *>(exception_object));
+    if (__unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase1(ex_ojb=%p): __unw_get_proc_info "
+          "failed => _URC_FATAL_PHASE1_ERROR",
+          static_cast<void *>(exception_object));
       return _URC_FATAL_PHASE1_ERROR;
     }
 
@@ -462,12 +464,12 @@ unwind_phase1(unw_context_t *uc, unw_cursor_t *cursor, _Unwind_Exception *except
       char functionBuf[512];
       const char *functionName = functionBuf;
       unw_word_t offset;
-      if ((unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
-                             &offset) != UNW_ESUCCESS) ||
+      if ((__unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
+                               &offset) != UNW_ESUCCESS) ||
           (frameInfo.start_ip + offset > frameInfo.end_ip))
         functionName = ".anonymous.";
       unw_word_t pc;
-      unw_get_reg(cursor, UNW_REG_IP, &pc);
+      __unw_get_reg(cursor, UNW_REG_IP, &pc);
       _LIBUNWIND_TRACE_UNWINDING(
           "unwind_phase1(ex_ojb=%p): pc=0x%" PRIxPTR ", start_ip=0x%" PRIxPTR ", func=%s, "
           "lsda=0x%" PRIxPTR ", personality=0x%" PRIxPTR,
@@ -537,7 +539,7 @@ static _Unwind_Reason_Code unwind_phase2(unw_context_t *uc, unw_cursor_t *cursor
                                          _Unwind_Exception *exception_object,
                                          bool resume) {
   // See comment at the start of unwind_phase1 regarding VRS integrity.
-  unw_init_local(cursor, uc);
+  __unw_init_local(cursor, uc);
 
   _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p)",
                              static_cast<void *>(exception_object));
@@ -559,19 +561,20 @@ static _Unwind_Reason_Code unwind_phase2(unw_context_t *uc, unw_cursor_t *cursor
       // for. After this, continue unwinding as if normal.
       //
       // See #7.4.6 for details.
-      unw_set_reg(cursor, UNW_REG_IP,
-                  exception_object->unwinder_cache.reserved2);
+      __unw_set_reg(cursor, UNW_REG_IP,
+                    exception_object->unwinder_cache.reserved2);
       resume = false;
     }
 
     // Get info about this frame.
     unw_word_t sp;
     unw_proc_info_t frameInfo;
-    unw_get_reg(cursor, UNW_REG_SP, &sp);
-    if (unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_get_proc_info "
-                                 "failed => _URC_FATAL_PHASE2_ERROR",
-                                 static_cast<void *>(exception_object));
+    __unw_get_reg(cursor, UNW_REG_SP, &sp);
+    if (__unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase2(ex_ojb=%p): __unw_get_proc_info "
+          "failed => _URC_FATAL_PHASE2_ERROR",
+          static_cast<void *>(exception_object));
       return _URC_FATAL_PHASE2_ERROR;
     }
 
@@ -580,8 +583,8 @@ static _Unwind_Reason_Code unwind_phase2(unw_context_t *uc, unw_cursor_t *cursor
       char functionBuf[512];
       const char *functionName = functionBuf;
       unw_word_t offset;
-      if ((unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
-                             &offset) != UNW_ESUCCESS) ||
+      if ((__unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
+                               &offset) != UNW_ESUCCESS) ||
           (frameInfo.start_ip + offset > frameInfo.end_ip))
         functionName = ".anonymous.";
       _LIBUNWIND_TRACE_UNWINDING(
@@ -625,8 +628,8 @@ static _Unwind_Reason_Code unwind_phase2(unw_context_t *uc, unw_cursor_t *cursor
         // We may get control back if landing pad calls _Unwind_Resume().
         if (_LIBUNWIND_TRACING_UNWINDING) {
           unw_word_t pc;
-          unw_get_reg(cursor, UNW_REG_IP, &pc);
-          unw_get_reg(cursor, UNW_REG_SP, &sp);
+          __unw_get_reg(cursor, UNW_REG_IP, &pc);
+          __unw_get_reg(cursor, UNW_REG_SP, &sp);
           _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): re-entering "
                                      "user code with ip=0x%" PRIxPTR ", sp=0x%" PRIxPTR,
                                      static_cast<void *>(exception_object),
@@ -637,11 +640,11 @@ static _Unwind_Reason_Code unwind_phase2(unw_context_t *uc, unw_cursor_t *cursor
           // EHABI #7.4.1 says we need to preserve pc for when _Unwind_Resume
           // is called back, to find this same frame.
           unw_word_t pc;
-          unw_get_reg(cursor, UNW_REG_IP, &pc);
+          __unw_get_reg(cursor, UNW_REG_IP, &pc);
           exception_object->unwinder_cache.reserved2 = (uint32_t)pc;
         }
-        unw_resume(cursor);
-        // unw_resume() only returns if there was an error.
+        __unw_resume(cursor);
+        // __unw_resume() only returns if there was an error.
         return _URC_FATAL_PHASE2_ERROR;
 
       // # EHABI #7.4.3
@@ -670,7 +673,7 @@ _Unwind_RaiseException(_Unwind_Exception *exception_object) {
                        static_cast<void *>(exception_object));
   unw_context_t uc;
   unw_cursor_t cursor;
-  unw_getcontext(&uc);
+  __unw_getcontext(&uc);
 
   // This field for is for compatibility with GCC to say this isn't a forced
   // unwind. EHABI #7.2
@@ -708,7 +711,7 @@ _Unwind_Resume(_Unwind_Exception *exception_object) {
                        static_cast<void *>(exception_object));
   unw_context_t uc;
   unw_cursor_t cursor;
-  unw_getcontext(&uc);
+  __unw_getcontext(&uc);
 
   // _Unwind_RaiseException on EHABI will always set the reserved1 field to 0,
   // which is in the same position as private_1 below.
@@ -725,7 +728,7 @@ _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) {
   unw_cursor_t *cursor = (unw_cursor_t *)context;
   unw_proc_info_t frameInfo;
   uintptr_t result = 0;
-  if (unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
+  if (__unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
     result = (uintptr_t)frameInfo.lsda;
   _LIBUNWIND_TRACE_API(
       "_Unwind_GetLanguageSpecificData(context=%p) => 0x%llx",
@@ -765,8 +768,8 @@ _Unwind_VRS_Set(_Unwind_Context *context, _Unwind_VRS_RegClass regclass,
     case _UVRSC_CORE:
       if (representation != _UVRSD_UINT32 || regno > 15)
         return _UVRSR_FAILED;
-      return unw_set_reg(cursor, (unw_regnum_t)(UNW_ARM_R0 + regno),
-                         *(unw_word_t *)valuep) == UNW_ESUCCESS
+      return __unw_set_reg(cursor, (unw_regnum_t)(UNW_ARM_R0 + regno),
+                           *(unw_word_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
     case _UVRSC_VFP:
@@ -776,28 +779,28 @@ _Unwind_VRS_Set(_Unwind_Context *context, _Unwind_VRS_RegClass regclass,
         // Can only touch d0-15 with FSTMFDX.
         if (regno > 15)
           return _UVRSR_FAILED;
-        unw_save_vfp_as_X(cursor);
+        __unw_save_vfp_as_X(cursor);
       } else {
         if (regno > 31)
           return _UVRSR_FAILED;
       }
-      return unw_set_fpreg(cursor, (unw_regnum_t)(UNW_ARM_D0 + regno),
-                           *(unw_fpreg_t *)valuep) == UNW_ESUCCESS
+      return __unw_set_fpreg(cursor, (unw_regnum_t)(UNW_ARM_D0 + regno),
+                             *(unw_fpreg_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
 #if defined(__ARM_WMMX)
     case _UVRSC_WMMXC:
       if (representation != _UVRSD_UINT32 || regno > 3)
         return _UVRSR_FAILED;
-      return unw_set_reg(cursor, (unw_regnum_t)(UNW_ARM_WC0 + regno),
-                         *(unw_word_t *)valuep) == UNW_ESUCCESS
+      return __unw_set_reg(cursor, (unw_regnum_t)(UNW_ARM_WC0 + regno),
+                           *(unw_word_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
     case _UVRSC_WMMXD:
       if (representation != _UVRSD_DOUBLE || regno > 31)
         return _UVRSR_FAILED;
-      return unw_set_fpreg(cursor, (unw_regnum_t)(UNW_ARM_WR0 + regno),
-                           *(unw_fpreg_t *)valuep) == UNW_ESUCCESS
+      return __unw_set_fpreg(cursor, (unw_regnum_t)(UNW_ARM_WR0 + regno),
+                             *(unw_fpreg_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
 #else
@@ -819,8 +822,8 @@ _Unwind_VRS_Get_Internal(_Unwind_Context *context,
     case _UVRSC_CORE:
       if (representation != _UVRSD_UINT32 || regno > 15)
         return _UVRSR_FAILED;
-      return unw_get_reg(cursor, (unw_regnum_t)(UNW_ARM_R0 + regno),
-                         (unw_word_t *)valuep) == UNW_ESUCCESS
+      return __unw_get_reg(cursor, (unw_regnum_t)(UNW_ARM_R0 + regno),
+                           (unw_word_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
     case _UVRSC_VFP:
@@ -830,28 +833,28 @@ _Unwind_VRS_Get_Internal(_Unwind_Context *context,
         // Can only touch d0-15 with FSTMFDX.
         if (regno > 15)
           return _UVRSR_FAILED;
-        unw_save_vfp_as_X(cursor);
+        __unw_save_vfp_as_X(cursor);
       } else {
         if (regno > 31)
           return _UVRSR_FAILED;
       }
-      return unw_get_fpreg(cursor, (unw_regnum_t)(UNW_ARM_D0 + regno),
-                           (unw_fpreg_t *)valuep) == UNW_ESUCCESS
+      return __unw_get_fpreg(cursor, (unw_regnum_t)(UNW_ARM_D0 + regno),
+                             (unw_fpreg_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
 #if defined(__ARM_WMMX)
     case _UVRSC_WMMXC:
       if (representation != _UVRSD_UINT32 || regno > 3)
         return _UVRSR_FAILED;
-      return unw_get_reg(cursor, (unw_regnum_t)(UNW_ARM_WC0 + regno),
-                         (unw_word_t *)valuep) == UNW_ESUCCESS
+      return __unw_get_reg(cursor, (unw_regnum_t)(UNW_ARM_WC0 + regno),
+                           (unw_word_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
     case _UVRSC_WMMXD:
       if (representation != _UVRSD_DOUBLE || regno > 31)
         return _UVRSR_FAILED;
-      return unw_get_fpreg(cursor, (unw_regnum_t)(UNW_ARM_WR0 + regno),
-                           (unw_fpreg_t *)valuep) == UNW_ESUCCESS
+      return __unw_get_fpreg(cursor, (unw_regnum_t)(UNW_ARM_WR0 + regno),
+                             (unw_fpreg_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
 #else
@@ -960,7 +963,7 @@ _Unwind_GetRegionStart(struct _Unwind_Context *context) {
   unw_cursor_t *cursor = (unw_cursor_t *)context;
   unw_proc_info_t frameInfo;
   uintptr_t result = 0;
-  if (unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
+  if (__unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
     result = (uintptr_t)frameInfo.start_ip;
   _LIBUNWIND_TRACE_API("_Unwind_GetRegionStart(context=%p) => 0x%llX",
                        static_cast<void *>(context), (long long)result);
@@ -983,7 +986,7 @@ extern "C" _LIBUNWIND_EXPORT _Unwind_Reason_Code
 __gnu_unwind_frame(_Unwind_Exception *exception_object,
                    struct _Unwind_Context *context) {
   unw_cursor_t *cursor = (unw_cursor_t *)context;
-  if (unw_step(cursor) != UNW_STEP_SUCCESS)
+  if (__unw_step(cursor) != UNW_STEP_SUCCESS)
     return _URC_FAILURE;
   return _URC_OK;
 }
diff --git a/src/Unwind-EHABI.h b/src/Unwind-EHABI.h
index fe164ff7be1e..6897082a337f 100644
--- a/src/Unwind-EHABI.h
+++ b/src/Unwind-EHABI.h
@@ -1,9 +1,8 @@
 //===------------------------- Unwind-EHABI.hpp ---------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 //===----------------------------------------------------------------------===//
diff --git a/src/Unwind-seh.cpp b/src/Unwind-seh.cpp
index c5cf7c47d40d..7647f2e0db0b 100644
--- a/src/Unwind-seh.cpp
+++ b/src/Unwind-seh.cpp
@@ -1,9 +1,8 @@
 //===--------------------------- Unwind-seh.cpp ---------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //===----------------------------------------------------------------------===//
 //
@@ -53,14 +52,16 @@ static const uint64_t kSEHExceptionClass = 0x434C4E4753454800; // CLNGSEH\0
 /// Exception cleanup routine used by \c _GCC_specific_handler to
 /// free foreign exceptions.
 static void seh_exc_cleanup(_Unwind_Reason_Code urc, _Unwind_Exception *exc) {
+  (void)urc;
   if (exc->exception_class != kSEHExceptionClass)
     _LIBUNWIND_ABORT("SEH cleanup called on non-SEH exception");
   free(exc);
 }
 
-static int _unw_init_seh(unw_cursor_t *cursor, CONTEXT *ctx);
-static DISPATCHER_CONTEXT *_unw_seh_get_disp_ctx(unw_cursor_t *cursor);
-static void _unw_seh_set_disp_ctx(unw_cursor_t *cursor, DISPATCHER_CONTEXT *disp);
+static int __unw_init_seh(unw_cursor_t *cursor, CONTEXT *ctx);
+static DISPATCHER_CONTEXT *__unw_seh_get_disp_ctx(unw_cursor_t *cursor);
+static void __unw_seh_set_disp_ctx(unw_cursor_t *cursor,
+                                   DISPATCHER_CONTEXT *disp);
 
 /// Common implementation of SEH-style handler functions used by Itanium-
 /// style frames.  Depending on how and why it was called, it may do one of:
@@ -69,7 +70,6 @@ static void _unw_seh_set_disp_ctx(unw_cursor_t *cursor, DISPATCHER_CONTEXT *disp
 _LIBUNWIND_EXPORT EXCEPTION_DISPOSITION
 _GCC_specific_handler(PEXCEPTION_RECORD ms_exc, PVOID frame, PCONTEXT ms_ctx,
                       DISPATCHER_CONTEXT *disp, __personality_routine pers) {
-  unw_context_t uc;
   unw_cursor_t cursor;
   _Unwind_Exception *exc;
   _Unwind_Action action;
@@ -78,7 +78,9 @@ _GCC_specific_handler(PEXCEPTION_RECORD ms_exc, PVOID frame, PCONTEXT ms_ctx,
   uintptr_t retval, target;
   bool ours = false;
 
-  _LIBUNWIND_TRACE_UNWINDING("_GCC_specific_handler(%#010x(%x), %p)", ms_exc->ExceptionCode, ms_exc->ExceptionFlags, frame);
+  _LIBUNWIND_TRACE_UNWINDING("_GCC_specific_handler(%#010lx(%lx), %p)",
+                             ms_exc->ExceptionCode, ms_exc->ExceptionFlags,
+                             (void *)frame);
   if (ms_exc->ExceptionCode == STATUS_GCC_UNWIND) {
     if (IS_TARGET_UNWIND(ms_exc->ExceptionFlags)) {
       // Set up the upper return value (the lower one and the target PC
@@ -112,9 +114,9 @@ _GCC_specific_handler(PEXCEPTION_RECORD ms_exc, PVOID frame, PCONTEXT ms_ctx,
     memset(exc->private_, 0, sizeof(exc->private_));
   }
   if (!ctx) {
-    _unw_init_seh(&cursor, disp->ContextRecord);
-    _unw_seh_set_disp_ctx(&cursor, disp);
-    unw_set_reg(&cursor, UNW_REG_IP, disp->ControlPc-1);
+    __unw_init_seh(&cursor, disp->ContextRecord);
+    __unw_seh_set_disp_ctx(&cursor, disp);
+    __unw_set_reg(&cursor, UNW_REG_IP, disp->ControlPc - 1);
     ctx = (struct _Unwind_Context *)&cursor;
 
     if (!IS_UNWINDING(ms_exc->ExceptionFlags)) {
@@ -130,7 +132,10 @@ _GCC_specific_handler(PEXCEPTION_RECORD ms_exc, PVOID frame, PCONTEXT ms_ctx,
     }
   }
 
-  _LIBUNWIND_TRACE_UNWINDING("_GCC_specific_handler() calling personality function %p(1, %d, %llx, %p, %p)", pers, action, exc->exception_class, exc, ctx);
+  _LIBUNWIND_TRACE_UNWINDING("_GCC_specific_handler() calling personality "
+                             "function %p(1, %d, %llx, %p, %p)",
+                             (void *)pers, action, exc->exception_class,
+                             (void *)exc, (void *)ctx);
   urc = pers(1, action, exc->exception_class, exc, ctx);
   _LIBUNWIND_TRACE_UNWINDING("_GCC_specific_handler() personality returned %d", urc);
   switch (urc) {
@@ -168,18 +173,18 @@ _GCC_specific_handler(PEXCEPTION_RECORD ms_exc, PVOID frame, PCONTEXT ms_ctx,
       _LIBUNWIND_ABORT("Personality installed context during phase 1!");
 #ifdef __x86_64__
     exc->private_[2] = disp->TargetIp;
-    unw_get_reg(&cursor, UNW_X86_64_RAX, &retval);
-    unw_get_reg(&cursor, UNW_X86_64_RDX, &exc->private_[3]);
+    __unw_get_reg(&cursor, UNW_X86_64_RAX, &retval);
+    __unw_get_reg(&cursor, UNW_X86_64_RDX, &exc->private_[3]);
 #elif defined(__arm__)
     exc->private_[2] = disp->TargetPc;
-    unw_get_reg(&cursor, UNW_ARM_R0, &retval);
-    unw_get_reg(&cursor, UNW_ARM_R1, &exc->private_[3]);
+    __unw_get_reg(&cursor, UNW_ARM_R0, &retval);
+    __unw_get_reg(&cursor, UNW_ARM_R1, &exc->private_[3]);
 #elif defined(__aarch64__)
     exc->private_[2] = disp->TargetPc;
-    unw_get_reg(&cursor, UNW_ARM64_X0, &retval);
-    unw_get_reg(&cursor, UNW_ARM64_X1, &exc->private_[3]);
+    __unw_get_reg(&cursor, UNW_ARM64_X0, &retval);
+    __unw_get_reg(&cursor, UNW_ARM64_X1, &exc->private_[3]);
 #endif
-    unw_get_reg(&cursor, UNW_REG_IP, &target);
+    __unw_get_reg(&cursor, UNW_REG_IP, &target);
     ms_exc->ExceptionCode = STATUS_GCC_UNWIND;
 #ifdef __x86_64__
     ms_exc->ExceptionInformation[2] = disp->TargetIp;
@@ -199,7 +204,7 @@ _GCC_specific_handler(PEXCEPTION_RECORD ms_exc, PVOID frame, PCONTEXT ms_ctx,
   }
 }
 
-/// Personality function returned by \c unw_get_proc_info() in SEH contexts.
+/// Personality function returned by \c __unw_get_proc_info() in SEH contexts.
 /// This is a wrapper that calls the real SEH handler function, which in
 /// turn (at least, for Itanium-style frames) calls the real Itanium
 /// personality function (see \c _GCC_specific_handler()).
@@ -207,6 +212,8 @@ extern "C" _Unwind_Reason_Code
 __libunwind_seh_personality(int version, _Unwind_Action state,
                             uint64_t klass, _Unwind_Exception *exc,
                             struct _Unwind_Context *context) {
+  (void)version;
+  (void)klass;
   EXCEPTION_RECORD ms_exc;
   bool phase2 = (state & (_UA_SEARCH_PHASE|_UA_CLEANUP_PHASE)) == _UA_CLEANUP_PHASE;
   ms_exc.ExceptionCode = STATUS_GCC_THROW;
@@ -215,7 +222,8 @@ __libunwind_seh_personality(int version, _Unwind_Action state,
   ms_exc.ExceptionInformation[0] = (ULONG_PTR)exc;
   ms_exc.ExceptionInformation[1] = (ULONG_PTR)context;
   ms_exc.ExceptionInformation[2] = state;
-  DISPATCHER_CONTEXT *disp_ctx = _unw_seh_get_disp_ctx((unw_cursor_t *)context);
+  DISPATCHER_CONTEXT *disp_ctx =
+      __unw_seh_get_disp_ctx((unw_cursor_t *)context);
   EXCEPTION_DISPOSITION ms_act = disp_ctx->LanguageHandler(&ms_exc,
                                                            (PVOID)disp_ctx->EstablisherFrame,
                                                            disp_ctx->ContextRecord,
@@ -234,15 +242,15 @@ unwind_phase2_forced(unw_context_t *uc,
                      _Unwind_Exception *exception_object,
                      _Unwind_Stop_Fn stop, void *stop_parameter) {
   unw_cursor_t cursor2;
-  unw_init_local(&cursor2, uc);
+  __unw_init_local(&cursor2, uc);
 
   // Walk each frame until we reach where search phase said to stop
-  while (unw_step(&cursor2) > 0) {
+  while (__unw_step(&cursor2) > 0) {
 
     // Update info about this frame.
     unw_proc_info_t frameInfo;
-    if (unw_get_proc_info(&cursor2, &frameInfo) != UNW_ESUCCESS) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): unw_step "
+    if (__unw_get_proc_info(&cursor2, &frameInfo) != UNW_ESUCCESS) {
+      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): __unw_step "
                                  "failed => _URC_END_OF_STACK",
                                  (void *)exception_object);
       return _URC_FATAL_PHASE2_ERROR;
@@ -253,8 +261,8 @@ unwind_phase2_forced(unw_context_t *uc,
       char functionBuf[512];
       const char *functionName = functionBuf;
       unw_word_t offset;
-      if ((unw_get_proc_name(&cursor2, functionBuf, sizeof(functionBuf),
-                             &offset) != UNW_ESUCCESS) ||
+      if ((__unw_get_proc_name(&cursor2, functionBuf, sizeof(functionBuf),
+                               &offset) != UNW_ESUCCESS) ||
           (frameInfo.start_ip + offset > frameInfo.end_ip))
         functionName = ".anonymous.";
       _LIBUNWIND_TRACE_UNWINDING(
@@ -304,7 +312,7 @@ unwind_phase2_forced(unw_context_t *uc,
                                    "_URC_INSTALL_CONTEXT",
                                    (void *)exception_object);
         // We may get control back if landing pad calls _Unwind_Resume().
-        unw_resume(&cursor2);
+        __unw_resume(&cursor2);
         break;
       default:
         // Personality routine returned an unknown result code.
@@ -369,7 +377,7 @@ _Unwind_Resume(_Unwind_Exception *exception_object) {
   if (exception_object->private_[0] != 0) {
     unw_context_t uc;
 
-    unw_getcontext(&uc);
+    __unw_getcontext(&uc);
     unwind_phase2_forced(&uc, exception_object,
                          (_Unwind_Stop_Fn) exception_object->private_[0],
                          (void *)exception_object->private_[4]);
@@ -407,7 +415,7 @@ _Unwind_ForcedUnwind(_Unwind_Exception *exception_object,
   _LIBUNWIND_TRACE_API("_Unwind_ForcedUnwind(ex_obj=%p, stop=%p)",
                        (void *)exception_object, (void *)(uintptr_t)stop);
   unw_context_t uc;
-  unw_getcontext(&uc);
+  __unw_getcontext(&uc);
 
   // Mark that this is a forced unwind, so _Unwind_Resume() can do
   // the right thing.
@@ -421,7 +429,8 @@ _Unwind_ForcedUnwind(_Unwind_Exception *exception_object,
 /// Called by personality handler during phase 2 to get LSDA for current frame.
 _LIBUNWIND_EXPORT uintptr_t
 _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) {
-  uintptr_t result = (uintptr_t)_unw_seh_get_disp_ctx((unw_cursor_t *)context)->HandlerData;
+  uintptr_t result =
+      (uintptr_t)__unw_seh_get_disp_ctx((unw_cursor_t *)context)->HandlerData;
   _LIBUNWIND_TRACE_API(
       "_Unwind_GetLanguageSpecificData(context=%p) => 0x%" PRIxPTR,
       (void *)context, result);
@@ -432,30 +441,32 @@ _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) {
 /// function.
 _LIBUNWIND_EXPORT uintptr_t
 _Unwind_GetRegionStart(struct _Unwind_Context *context) {
-  DISPATCHER_CONTEXT *disp = _unw_seh_get_disp_ctx((unw_cursor_t *)context);
+  DISPATCHER_CONTEXT *disp = __unw_seh_get_disp_ctx((unw_cursor_t *)context);
   uintptr_t result = (uintptr_t)disp->FunctionEntry->BeginAddress + disp->ImageBase;
   _LIBUNWIND_TRACE_API("_Unwind_GetRegionStart(context=%p) => 0x%" PRIxPTR,
                        (void *)context, result);
   return result;
 }
 
-static int
-_unw_init_seh(unw_cursor_t *cursor, CONTEXT *context) {
+static int __unw_init_seh(unw_cursor_t *cursor, CONTEXT *context) {
 #ifdef _LIBUNWIND_TARGET_X86_64
-  new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_x86_64>(
-      context, LocalAddressSpace::sThisAddressSpace);
+  new (reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_x86_64> *>(cursor))
+      UnwindCursor<LocalAddressSpace, Registers_x86_64>(
+          context, LocalAddressSpace::sThisAddressSpace);
   auto *co = reinterpret_cast<AbstractUnwindCursor *>(cursor);
   co->setInfoBasedOnIPRegister();
   return UNW_ESUCCESS;
 #elif defined(_LIBUNWIND_TARGET_ARM)
-  new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_arm>(
-      context, LocalAddressSpace::sThisAddressSpace);
+  new (reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm> *>(cursor))
+      UnwindCursor<LocalAddressSpace, Registers_arm>(
+          context, LocalAddressSpace::sThisAddressSpace);
   auto *co = reinterpret_cast<AbstractUnwindCursor *>(cursor);
   co->setInfoBasedOnIPRegister();
   return UNW_ESUCCESS;
 #elif defined(_LIBUNWIND_TARGET_AARCH64)
-  new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_arm64>(
-      context, LocalAddressSpace::sThisAddressSpace);
+  new (reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_arm64> *>(cursor))
+      UnwindCursor<LocalAddressSpace, Registers_arm64>(
+          context, LocalAddressSpace::sThisAddressSpace);
   auto *co = reinterpret_cast<AbstractUnwindCursor *>(cursor);
   co->setInfoBasedOnIPRegister();
   return UNW_ESUCCESS;
@@ -464,8 +475,7 @@ _unw_init_seh(unw_cursor_t *cursor, CONTEXT *context) {
 #endif
 }
 
-static DISPATCHER_CONTEXT *
-_unw_seh_get_disp_ctx(unw_cursor_t *cursor) {
+static DISPATCHER_CONTEXT *__unw_seh_get_disp_ctx(unw_cursor_t *cursor) {
 #ifdef _LIBUNWIND_TARGET_X86_64
   return reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_x86_64> *>(cursor)->getDispatcherContext();
 #elif defined(_LIBUNWIND_TARGET_ARM)
@@ -477,8 +487,8 @@ _unw_seh_get_disp_ctx(unw_cursor_t *cursor) {
 #endif
 }
 
-static void
-_unw_seh_set_disp_ctx(unw_cursor_t *cursor, DISPATCHER_CONTEXT *disp) {
+static void __unw_seh_set_disp_ctx(unw_cursor_t *cursor,
+                                   DISPATCHER_CONTEXT *disp) {
 #ifdef _LIBUNWIND_TARGET_X86_64
   reinterpret_cast<UnwindCursor<LocalAddressSpace, Registers_x86_64> *>(cursor)->setDispatcherContext(disp);
 #elif defined(_LIBUNWIND_TARGET_ARM)
diff --git a/src/Unwind-sjlj.c b/src/Unwind-sjlj.c
index 90cac3f8c763..b8bb7c83bdff 100644
--- a/src/Unwind-sjlj.c
+++ b/src/Unwind-sjlj.c
@@ -1,9 +1,8 @@
 //===--------------------------- Unwind-sjlj.c ----------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
@@ -12,6 +11,7 @@
 
 #include <unwind.h>
 
+#include <inttypes.h>
 #include <stdint.h>
 #include <stdbool.h>
 #include <stdlib.h>
@@ -52,7 +52,7 @@ struct _Unwind_FunctionContext {
 #else
 # if __STDC_VERSION__ >= 201112L
 #  define _LIBUNWIND_THREAD_LOCAL _Thread_local
-# elif defined(_WIN32)
+# elif defined(_MSC_VER)
 #  define _LIBUNWIND_THREAD_LOCAL __declspec(thread)
 # elif defined(__GNUC__) || defined(__clang__)
 #  define _LIBUNWIND_THREAD_LOCAL __thread
@@ -108,7 +108,8 @@ _Unwind_SjLj_Unregister(struct _Unwind_FunctionContext *fc) {
 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", c);
+  _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) {
@@ -117,17 +118,18 @@ unwind_phase1(struct _Unwind_Exception *exception_object) {
     if (c == NULL) {
       _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): reached "
                                  "bottom => _URC_END_OF_STACK",
-                                  exception_object);
+                                 (void *)exception_object);
       return _URC_END_OF_STACK;
     }
 
-    _LIBUNWIND_TRACE_UNWINDING("unwind_phase1: function-context=%p", c);
+    _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",
-                                 exception_object, c->personality);
+                                 "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);
@@ -138,12 +140,14 @@ unwind_phase1(struct _Unwind_Exception *exception_object) {
         handlerNotFound = false;
         exception_object->private_2 = (uintptr_t) c;
         _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): "
-                                   "_URC_HANDLER_FOUND", exception_object);
+                                   "_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", exception_object);
+                                   "_URC_CONTINUE_UNWIND",
+                                   (void *)exception_object);
         // continue unwinding
         break;
 
@@ -151,7 +155,7 @@ unwind_phase1(struct _Unwind_Exception *exception_object) {
         // something went wrong
         _LIBUNWIND_TRACE_UNWINDING(
             "unwind_phase1(ex_ojb=%p): _URC_FATAL_PHASE1_ERROR",
-            exception_object);
+            (void *)exception_object);
         return _URC_FATAL_PHASE1_ERROR;
       }
     }
@@ -162,19 +166,21 @@ unwind_phase1(struct _Unwind_Exception *exception_object) {
 
 static _Unwind_Reason_Code
 unwind_phase2(struct _Unwind_Exception *exception_object) {
-  _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p)", 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",
-                              exception_object, c);
+                               (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",
-                                 exception_object);
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase2(ex_ojb=%p): __unw_step() reached "
+          "bottom => _URC_END_OF_STACK",
+          (void *)exception_object);
       return _URC_END_OF_STACK;
     }
 
@@ -194,7 +200,7 @@ unwind_phase2(struct _Unwind_Exception *exception_object) {
         // continue unwinding
         _LIBUNWIND_TRACE_UNWINDING(
             "unwind_phase2(ex_ojb=%p): _URC_CONTINUE_UNWIND",
-            exception_object);
+            (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 "
@@ -203,14 +209,14 @@ unwind_phase2(struct _Unwind_Exception *exception_object) {
         break;
       case _URC_INSTALL_CONTEXT:
         _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): "
-                                  "_URC_INSTALL_CONTEXT, will resume at "
-                                  "landing pad %p",
-                                  exception_object, c->jbuf[1]);
+                                   "_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
+        // __unw_resume() only returns if there was an error
         return _URC_FATAL_PHASE2_ERROR;
       default:
         // something went wrong
@@ -237,9 +243,10 @@ unwind_phase2_forced(struct _Unwind_Exception *exception_object,
 
     // 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",
-                                 exception_object);
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase2(ex_ojb=%p): __unw_step() reached "
+          "bottom => _URC_END_OF_STACK",
+          (void *)exception_object);
       return _URC_END_OF_STACK;
     }
 
@@ -251,11 +258,11 @@ unwind_phase2_forced(struct _Unwind_Exception *exception_object,
                 (struct _Unwind_Context *)c, stop_parameter);
     _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
                                "stop function returned %d",
-                                exception_object, stopResult);
+                               (void *)exception_object, stopResult);
     if (stopResult != _URC_NO_REASON) {
       _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
                                  "stopped by stop function",
-                                  exception_object);
+                                 (void *)exception_object);
       return _URC_FATAL_PHASE2_ERROR;
     }
 
@@ -264,7 +271,7 @@ unwind_phase2_forced(struct _Unwind_Exception *exception_object,
       __personality_routine p = (__personality_routine) c->personality;
       _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
                                  "calling personality function %p",
-                                  exception_object, p);
+                                 (void *)exception_object, (void *)p);
       _Unwind_Reason_Code personalityResult =
           (*p)(1, action, exception_object->exception_class, exception_object,
                (struct _Unwind_Context *)c);
@@ -272,13 +279,13 @@ unwind_phase2_forced(struct _Unwind_Exception *exception_object,
       case _URC_CONTINUE_UNWIND:
         _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p):  "
                                    "personality returned _URC_CONTINUE_UNWIND",
-                                    exception_object);
+                                   (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",
-                                    exception_object);
+                                   (void *)exception_object);
         // we may get control back if landing pad calls _Unwind_Resume()
         __Unwind_SjLj_SetTopOfFunctionStack(c);
         __builtin_longjmp(c->jbuf, 1);
@@ -288,7 +295,7 @@ unwind_phase2_forced(struct _Unwind_Exception *exception_object,
         _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
                                    "personality returned %d, "
                                    "_URC_FATAL_PHASE2_ERROR",
-                                    exception_object, personalityResult);
+                                   (void *)exception_object, personalityResult);
         return _URC_FATAL_PHASE2_ERROR;
       }
     }
@@ -298,8 +305,8 @@ unwind_phase2_forced(struct _Unwind_Exception *exception_object,
   // 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",
-                        exception_object);
+                             "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,
@@ -314,7 +321,8 @@ unwind_phase2_forced(struct _Unwind_Exception *exception_object,
 /// 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)", 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
@@ -344,7 +352,8 @@ _Unwind_SjLj_RaiseException(struct _Unwind_Exception *exception_object) {
 /// __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)", 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,
@@ -362,8 +371,8 @@ _Unwind_SjLj_Resume(struct _Unwind_Exception *exception_object) {
 _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=%ld",
-                              exception_object, exception_object->private_1);
+                       "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.
@@ -386,7 +395,8 @@ _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%0lX",  context, ufc->lsda);
+                       "=> 0x%" PRIuPTR,
+                       (void *)context, ufc->lsda);
   return ufc->lsda;
 }
 
@@ -394,8 +404,8 @@ _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) {
 /// 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)",
-                             context, 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];
 }
@@ -404,8 +414,9 @@ _LIBUNWIND_EXPORT uintptr_t _Unwind_GetGR(struct _Unwind_Context *context,
 /// 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%0lX)"
-                            , context, index, 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;
 }
@@ -414,8 +425,8 @@ _LIBUNWIND_EXPORT void _Unwind_SetGR(struct _Unwind_Context *context, int index,
 /// 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%lX", context,
-                  ufc->resumeLocation + 1);
+  _LIBUNWIND_TRACE_API("_Unwind_GetIP(context=%p) => 0x%" PRIu32,
+                       (void *)context, ufc->resumeLocation + 1);
   return ufc->resumeLocation + 1;
 }
 
@@ -427,8 +438,9 @@ _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%lX",
-                             context, ipBefore, ufc->resumeLocation + 1);
+  _LIBUNWIND_TRACE_API("_Unwind_GetIPInfo(context=%p, %p) => 0x%" PRIu32,
+                       (void *)context, (void *)ipBefore,
+                       ufc->resumeLocation + 1);
   return ufc->resumeLocation + 1;
 }
 
@@ -436,8 +448,8 @@ _LIBUNWIND_EXPORT uintptr_t _Unwind_GetIPInfo(struct _Unwind_Context *context,
 /// 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%0lX)",
-                             context, 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;
 }
@@ -449,7 +461,7 @@ _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)", context);
+  _LIBUNWIND_TRACE_API("_Unwind_GetRegionStart(context=%p)", (void *)context);
   return 0;
 }
 
@@ -459,7 +471,7 @@ _Unwind_GetRegionStart(struct _Unwind_Context *context) {
 _LIBUNWIND_EXPORT void
 _Unwind_DeleteException(struct _Unwind_Exception *exception_object) {
   _LIBUNWIND_TRACE_API("_Unwind_DeleteException(ex_obj=%p)",
-                              exception_object);
+                       (void *)exception_object);
   if (exception_object->exception_cleanup != NULL)
     (*exception_object->exception_cleanup)(_URC_FOREIGN_EXCEPTION_CAUGHT,
                                            exception_object);
@@ -473,7 +485,7 @@ _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)", context);
+  _LIBUNWIND_TRACE_API("_Unwind_GetDataRelBase(context=%p)", (void *)context);
   _LIBUNWIND_ABORT("_Unwind_GetDataRelBase() not implemented");
 }
 
@@ -484,14 +496,14 @@ _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)", 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)", 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.
diff --git a/src/UnwindCursor.hpp b/src/UnwindCursor.hpp
index 52439f9b5453..a96c9f39958d 100644
--- a/src/UnwindCursor.hpp
+++ b/src/UnwindCursor.hpp
@@ -1,9 +1,8 @@
 //===------------------------- UnwindCursor.hpp ---------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 // C++ interface to lower levels of libunwind
@@ -12,7 +11,6 @@
 #ifndef __UNWINDCURSOR_HPP__
 #define __UNWINDCURSOR_HPP__
 
-#include <algorithm>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -106,7 +104,6 @@ private:
   static void dyldUnloadHook(const struct mach_header *mh, intptr_t slide);
   static bool _registeredForDyldUnloads;
 #endif
-  // Can't use std::vector<> here because this code is below libc++.
   static entry *_buffer;
   static entry *_bufferUsed;
   static entry *_bufferEnd;
@@ -485,6 +482,10 @@ public:
   DISPATCHER_CONTEXT *getDispatcherContext() { return &_dispContext; }
   void setDispatcherContext(DISPATCHER_CONTEXT *disp) { _dispContext = *disp; }
 
+  // libunwind does not and should not depend on C++ library which means that we
+  // need our own defition of inline placement new.
+  static void *operator new(size_t, UnwindCursor<A, R> *p) { return p; }
+
 private:
 
   pint_t getLastPC() const { return _dispContext.ControlPc; }
@@ -789,6 +790,8 @@ bool UnwindCursor<A, R>::validFloatReg(int regNum) {
   if (regNum >= UNW_ARM_D0 && regNum <= UNW_ARM_D31) return true;
 #elif defined(_LIBUNWIND_TARGET_AARCH64)
   if (regNum >= UNW_ARM64_D0 && regNum <= UNW_ARM64_D31) return true;
+#else
+  (void)regNum;
 #endif
   return false;
 }
@@ -816,6 +819,7 @@ unw_fpreg_t UnwindCursor<A, R>::getFloatReg(int regNum) {
 #elif defined(_LIBUNWIND_TARGET_AARCH64)
   return _msContext.V[regNum - UNW_ARM64_D0].D[0];
 #else
+  (void)regNum;
   _LIBUNWIND_ABORT("float registers unimplemented");
 #endif
 }
@@ -843,6 +847,8 @@ void UnwindCursor<A, R>::setFloatReg(int regNum, unw_fpreg_t value) {
 #elif defined(_LIBUNWIND_TARGET_AARCH64)
   _msContext.V[regNum - UNW_ARM64_D0].D[0] = value;
 #else
+  (void)regNum;
+  (void)value;
   _LIBUNWIND_ABORT("float registers unimplemented");
 #endif
 }
@@ -892,6 +898,10 @@ public:
   virtual void        saveVFPAsX();
 #endif
 
+  // libunwind does not and should not depend on C++ library which means that we
+  // need our own defition of inline placement new.
+  static void *operator new(size_t, UnwindCursor<A, R> *p) { return p; }
+
 private:
 
 #if defined(_LIBUNWIND_ARM_EHABI)
@@ -1221,7 +1231,6 @@ template<typename A>
 struct EHABISectionIterator {
   typedef EHABISectionIterator _Self;
 
-  typedef std::random_access_iterator_tag iterator_category;
   typedef typename A::pint_t value_type;
   typedef typename A::pint_t* pointer;
   typedef typename A::pint_t& reference;
@@ -1275,6 +1284,29 @@ struct EHABISectionIterator {
   const UnwindInfoSections* _sects;
 };
 
+namespace {
+
+template <typename A>
+EHABISectionIterator<A> EHABISectionUpperBound(
+    EHABISectionIterator<A> first,
+    EHABISectionIterator<A> last,
+    typename A::pint_t value) {
+  size_t len = last - first;
+  while (len > 0) {
+    size_t l2 = len / 2;
+    EHABISectionIterator<A> m = first + l2;
+    if (value < *m) {
+        len = l2;
+    } else {
+        first = ++m;
+        len -= l2 + 1;
+    }
+  }
+  return first;
+}
+
+}
+
 template <typename A, typename R>
 bool UnwindCursor<A, R>::getInfoFromEHABISection(
     pint_t pc,
@@ -1286,7 +1318,7 @@ bool UnwindCursor<A, R>::getInfoFromEHABISection(
   if (begin == end)
     return false;
 
-  EHABISectionIterator<A> itNextPC = std::upper_bound(begin, end, pc);
+  EHABISectionIterator<A> itNextPC = EHABISectionUpperBound(begin, end, pc);
   if (itNextPC == begin)
     return false;
   EHABISectionIterator<A> itThisPC = itNextPC - 1;
@@ -1296,8 +1328,7 @@ bool UnwindCursor<A, R>::getInfoFromEHABISection(
   // in the table, we don't really know the function extent and have to choose a
   // value for nextPC. Choosing max() will allow the range check during trace to
   // succeed.
-  pint_t nextPC = (itNextPC == end) ? std::numeric_limits<pint_t>::max()
-                                    : itNextPC.functionAddress();
+  pint_t nextPC = (itNextPC == end) ? UINTPTR_MAX : itNextPC.functionAddress();
   pint_t indexDataAddr = itThisPC.dataAddress();
 
   if (indexDataAddr == 0)
@@ -1709,7 +1740,7 @@ bool UnwindCursor<A, R>::getInfoFromCompactEncodingSection(pint_t pc,
     --personalityIndex; // change 1-based to zero-based index
     if (personalityIndex > sectionHeader.personalityArrayCount()) {
       _LIBUNWIND_DEBUG_LOG("found encoding 0x%08X with personality index %d,  "
-                            "but personality table has only %d entires",
+                            "but personality table has only %d entries",
                             encoding, personalityIndex,
                             sectionHeader.personalityArrayCount());
       return false;
diff --git a/src/UnwindLevel1-gcc-ext.c b/src/UnwindLevel1-gcc-ext.c
index 1c6626585465..63e4083a4579 100644
--- a/src/UnwindLevel1-gcc-ext.c
+++ b/src/UnwindLevel1-gcc-ext.c
@@ -1,9 +1,8 @@
 //===--------------------- UnwindLevel1-gcc-ext.c -------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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 gcc extensions to the C++ ABI Exception Handling Level 1.
@@ -94,10 +93,10 @@ _LIBUNWIND_EXPORT void *_Unwind_FindEnclosingFunction(void *pc) {
   unw_cursor_t cursor;
   unw_context_t uc;
   unw_proc_info_t info;
-  unw_getcontext(&uc);
-  unw_init_local(&cursor, &uc);
-  unw_set_reg(&cursor, UNW_REG_IP, (unw_word_t)(intptr_t) pc);
-  if (unw_get_proc_info(&cursor, &info) == UNW_ESUCCESS)
+  __unw_getcontext(&uc);
+  __unw_init_local(&cursor, &uc);
+  __unw_set_reg(&cursor, UNW_REG_IP, (unw_word_t)(intptr_t)pc);
+  if (__unw_get_proc_info(&cursor, &info) == UNW_ESUCCESS)
     return (void *)(intptr_t) info.start_ip;
   else
     return NULL;
@@ -109,8 +108,8 @@ _LIBUNWIND_EXPORT _Unwind_Reason_Code
 _Unwind_Backtrace(_Unwind_Trace_Fn callback, void *ref) {
   unw_cursor_t cursor;
   unw_context_t uc;
-  unw_getcontext(&uc);
-  unw_init_local(&cursor, &uc);
+  __unw_getcontext(&uc);
+  __unw_init_local(&cursor, &uc);
 
   _LIBUNWIND_TRACE_API("_Unwind_Backtrace(callback=%p)",
                        (void *)(uintptr_t)callback);
@@ -129,7 +128,7 @@ _Unwind_Backtrace(_Unwind_Trace_Fn callback, void *ref) {
 #if !defined(_LIBUNWIND_ARM_EHABI)
     // ask libunwind to get next frame (skip over first frame which is
     // _Unwind_Backtrace())
-    if (unw_step(&cursor) <= 0) {
+    if (__unw_step(&cursor) <= 0) {
       _LIBUNWIND_TRACE_UNWINDING(" _backtrace: ended because cursor reached "
                                  "bottom of stack, returning %d",
                                  _URC_END_OF_STACK);
@@ -138,7 +137,7 @@ _Unwind_Backtrace(_Unwind_Trace_Fn callback, void *ref) {
 #else
     // Get the information for this frame.
     unw_proc_info_t frameInfo;
-    if (unw_get_proc_info(&cursor, &frameInfo) != UNW_ESUCCESS) {
+    if (__unw_get_proc_info(&cursor, &frameInfo) != UNW_ESUCCESS) {
       return _URC_END_OF_STACK;
     }
 
@@ -165,8 +164,8 @@ _Unwind_Backtrace(_Unwind_Trace_Fn callback, void *ref) {
       char functionName[512];
       unw_proc_info_t frame;
       unw_word_t offset;
-      unw_get_proc_name(&cursor, functionName, 512, &offset);
-      unw_get_proc_info(&cursor, &frame);
+      __unw_get_proc_name(&cursor, functionName, 512, &offset);
+      __unw_get_proc_info(&cursor, &frame);
       _LIBUNWIND_TRACE_UNWINDING(
           " _backtrace: start_ip=0x%" PRIxPTR ", func=%s, lsda=0x%" PRIxPTR ", context=%p",
           frame.start_ip, functionName, frame.lsda,
@@ -192,10 +191,10 @@ _LIBUNWIND_EXPORT const void *_Unwind_Find_FDE(const void *pc,
   unw_cursor_t cursor;
   unw_context_t uc;
   unw_proc_info_t info;
-  unw_getcontext(&uc);
-  unw_init_local(&cursor, &uc);
-  unw_set_reg(&cursor, UNW_REG_IP, (unw_word_t)(intptr_t) pc);
-  unw_get_proc_info(&cursor, &info);
+  __unw_getcontext(&uc);
+  __unw_init_local(&cursor, &uc);
+  __unw_set_reg(&cursor, UNW_REG_IP, (unw_word_t)(intptr_t)pc);
+  __unw_get_proc_info(&cursor, &info);
   bases->tbase = (uintptr_t)info.extra;
   bases->dbase = 0; // dbase not used on Mac OS X
   bases->func = (uintptr_t)info.start_ip;
@@ -209,7 +208,7 @@ _LIBUNWIND_EXPORT const void *_Unwind_Find_FDE(const void *pc,
 _LIBUNWIND_EXPORT uintptr_t _Unwind_GetCFA(struct _Unwind_Context *context) {
   unw_cursor_t *cursor = (unw_cursor_t *)context;
   unw_word_t result;
-  unw_get_reg(cursor, UNW_REG_SP, &result);
+  __unw_get_reg(cursor, UNW_REG_SP, &result);
   _LIBUNWIND_TRACE_API("_Unwind_GetCFA(context=%p) => 0x%" PRIxPTR,
                        (void *)context, result);
   return (uintptr_t)result;
@@ -234,7 +233,7 @@ _LIBUNWIND_EXPORT uintptr_t _Unwind_GetIPInfo(struct _Unwind_Context *context,
 /// was broken until 10.6.
 _LIBUNWIND_EXPORT void __register_frame(const void *fde) {
   _LIBUNWIND_TRACE_API("__register_frame(%p)", fde);
-  _unw_add_dynamic_fde((unw_word_t)(uintptr_t) fde);
+  __unw_add_dynamic_fde((unw_word_t)(uintptr_t)fde);
 }
 
 
@@ -244,7 +243,7 @@ _LIBUNWIND_EXPORT void __register_frame(const void *fde) {
 /// was broken until 10.6.
 _LIBUNWIND_EXPORT void __deregister_frame(const void *fde) {
   _LIBUNWIND_TRACE_API("__deregister_frame(%p)", fde);
-  _unw_remove_dynamic_fde((unw_word_t)(uintptr_t) fde);
+  __unw_remove_dynamic_fde((unw_word_t)(uintptr_t)fde);
 }
 
 
diff --git a/src/UnwindLevel1.c b/src/UnwindLevel1.c
index 0a04438bba2f..bcb1a7fbec2a 100644
--- a/src/UnwindLevel1.c
+++ b/src/UnwindLevel1.c
@@ -1,13 +1,12 @@
 //===------------------------- UnwindLevel1.c -----------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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 C++ ABI Exception Handling Level 1 as documented at:
-//      http://mentorembedded.github.io/cxx-abi/abi-eh.html
+//      https://itanium-cxx-abi.github.io/cxx-abi/abi-eh.html
 // using libunwind
 //
 //===----------------------------------------------------------------------===//
@@ -26,9 +25,10 @@
 #include <stdio.h>
 #include <string.h>
 
+#include "config.h"
 #include "libunwind.h"
+#include "libunwind_ext.h"
 #include "unwind.h"
-#include "config.h"
 
 #if !defined(_LIBUNWIND_ARM_EHABI) && !defined(__USING_SJLJ_EXCEPTIONS__)
 
@@ -36,33 +36,36 @@
 
 static _Unwind_Reason_Code
 unwind_phase1(unw_context_t *uc, unw_cursor_t *cursor, _Unwind_Exception *exception_object) {
-  unw_init_local(cursor, uc);
+  __unw_init_local(cursor, uc);
 
   // Walk each frame looking for a place to stop.
   bool handlerNotFound = true;
   while (handlerNotFound) {
     // Ask libunwind to get next frame (skip over first which is
     // _Unwind_RaiseException).
-    int stepResult = unw_step(cursor);
+    int stepResult = __unw_step(cursor);
     if (stepResult == 0) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): unw_step() reached "
-                                 "bottom => _URC_END_OF_STACK",
-                                 (void *)exception_object);
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase1(ex_ojb=%p): __unw_step() reached "
+          "bottom => _URC_END_OF_STACK",
+          (void *)exception_object);
       return _URC_END_OF_STACK;
     } else if (stepResult < 0) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): unw_step failed => "
-                                 "_URC_FATAL_PHASE1_ERROR",
-                                 (void *)exception_object);
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase1(ex_ojb=%p): __unw_step failed => "
+          "_URC_FATAL_PHASE1_ERROR",
+          (void *)exception_object);
       return _URC_FATAL_PHASE1_ERROR;
     }
 
     // See if frame has code to run (has personality routine).
     unw_proc_info_t frameInfo;
     unw_word_t sp;
-    if (unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): unw_get_proc_info "
-                                 "failed => _URC_FATAL_PHASE1_ERROR",
-                                 (void *)exception_object);
+    if (__unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase1(ex_ojb=%p): __unw_get_proc_info "
+          "failed => _URC_FATAL_PHASE1_ERROR",
+          (void *)exception_object);
       return _URC_FATAL_PHASE1_ERROR;
     }
 
@@ -71,12 +74,12 @@ unwind_phase1(unw_context_t *uc, unw_cursor_t *cursor, _Unwind_Exception *except
       char functionBuf[512];
       const char *functionName = functionBuf;
       unw_word_t offset;
-      if ((unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
-                             &offset) != UNW_ESUCCESS) ||
+      if ((__unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
+                               &offset) != UNW_ESUCCESS) ||
           (frameInfo.start_ip + offset > frameInfo.end_ip))
         functionName = ".anonymous.";
       unw_word_t pc;
-      unw_get_reg(cursor, UNW_REG_IP, &pc);
+      __unw_get_reg(cursor, UNW_REG_IP, &pc);
       _LIBUNWIND_TRACE_UNWINDING(
           "unwind_phase1(ex_ojb=%p): pc=0x%" PRIxPTR ", start_ip=0x%" PRIxPTR
           ", func=%s, lsda=0x%" PRIxPTR ", personality=0x%" PRIxPTR "",
@@ -100,7 +103,7 @@ unwind_phase1(unw_context_t *uc, unw_cursor_t *cursor, _Unwind_Exception *except
         // found a catch clause or locals that need destructing in this frame
         // stop search and remember stack pointer at the frame
         handlerNotFound = false;
-        unw_get_reg(cursor, UNW_REG_SP, &sp);
+        __unw_get_reg(cursor, UNW_REG_SP, &sp);
         exception_object->private_2 = (uintptr_t)sp;
         _LIBUNWIND_TRACE_UNWINDING(
             "unwind_phase1(ex_ojb=%p): _URC_HANDLER_FOUND",
@@ -129,7 +132,7 @@ unwind_phase1(unw_context_t *uc, unw_cursor_t *cursor, _Unwind_Exception *except
 
 static _Unwind_Reason_Code
 unwind_phase2(unw_context_t *uc, unw_cursor_t *cursor, _Unwind_Exception *exception_object) {
-  unw_init_local(cursor, uc);
+  __unw_init_local(cursor, uc);
 
   _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p)",
                              (void *)exception_object);
@@ -139,27 +142,30 @@ unwind_phase2(unw_context_t *uc, unw_cursor_t *cursor, _Unwind_Exception *except
 
     // Ask libunwind to get next frame (skip over first which is
     // _Unwind_RaiseException).
-    int stepResult = unw_step(cursor);
+    int stepResult = __unw_step(cursor);
     if (stepResult == 0) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_step() reached "
-                                 "bottom => _URC_END_OF_STACK",
-                                 (void *)exception_object);
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase2(ex_ojb=%p): __unw_step() reached "
+          "bottom => _URC_END_OF_STACK",
+          (void *)exception_object);
       return _URC_END_OF_STACK;
     } else if (stepResult < 0) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_step failed => "
-                                 "_URC_FATAL_PHASE1_ERROR",
-                                 (void *)exception_object);
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase2(ex_ojb=%p): __unw_step failed => "
+          "_URC_FATAL_PHASE1_ERROR",
+          (void *)exception_object);
       return _URC_FATAL_PHASE2_ERROR;
     }
 
     // Get info about this frame.
     unw_word_t sp;
     unw_proc_info_t frameInfo;
-    unw_get_reg(cursor, UNW_REG_SP, &sp);
-    if (unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_get_proc_info "
-                                 "failed => _URC_FATAL_PHASE1_ERROR",
-                                 (void *)exception_object);
+    __unw_get_reg(cursor, UNW_REG_SP, &sp);
+    if (__unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
+      _LIBUNWIND_TRACE_UNWINDING(
+          "unwind_phase2(ex_ojb=%p): __unw_get_proc_info "
+          "failed => _URC_FATAL_PHASE1_ERROR",
+          (void *)exception_object);
       return _URC_FATAL_PHASE2_ERROR;
     }
 
@@ -168,8 +174,8 @@ unwind_phase2(unw_context_t *uc, unw_cursor_t *cursor, _Unwind_Exception *except
       char functionBuf[512];
       const char *functionName = functionBuf;
       unw_word_t offset;
-      if ((unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
-                             &offset) != UNW_ESUCCESS) ||
+      if ((__unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
+                               &offset) != UNW_ESUCCESS) ||
           (frameInfo.start_ip + offset > frameInfo.end_ip))
         functionName = ".anonymous.";
       _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): start_ip=0x%" PRIxPTR
@@ -212,15 +218,15 @@ unwind_phase2(unw_context_t *uc, unw_cursor_t *cursor, _Unwind_Exception *except
         // We may get control back if landing pad calls _Unwind_Resume().
         if (_LIBUNWIND_TRACING_UNWINDING) {
           unw_word_t pc;
-          unw_get_reg(cursor, UNW_REG_IP, &pc);
-          unw_get_reg(cursor, UNW_REG_SP, &sp);
+          __unw_get_reg(cursor, UNW_REG_IP, &pc);
+          __unw_get_reg(cursor, UNW_REG_SP, &sp);
           _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): re-entering "
                                      "user code with ip=0x%" PRIxPTR
                                      ", sp=0x%" PRIxPTR,
                                      (void *)exception_object, pc, sp);
         }
-        unw_resume(cursor);
-        // unw_resume() only returns if there was an error.
+        __unw_resume(cursor);
+        // __unw_resume() only returns if there was an error.
         return _URC_FATAL_PHASE2_ERROR;
       default:
         // Personality routine returned an unknown result code.
@@ -240,15 +246,15 @@ static _Unwind_Reason_Code
 unwind_phase2_forced(unw_context_t *uc, unw_cursor_t *cursor,
                      _Unwind_Exception *exception_object,
                      _Unwind_Stop_Fn stop, void *stop_parameter) {
-  unw_init_local(cursor, uc);
+  __unw_init_local(cursor, uc);
 
   // Walk each frame until we reach where search phase said to stop
-  while (unw_step(cursor) > 0) {
+  while (__unw_step(cursor) > 0) {
 
     // Update info about this frame.
     unw_proc_info_t frameInfo;
-    if (unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): unw_step "
+    if (__unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
+      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): __unw_step "
                                  "failed => _URC_END_OF_STACK",
                                  (void *)exception_object);
       return _URC_FATAL_PHASE2_ERROR;
@@ -259,8 +265,8 @@ unwind_phase2_forced(unw_context_t *uc, unw_cursor_t *cursor,
       char functionBuf[512];
       const char *functionName = functionBuf;
       unw_word_t offset;
-      if ((unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
-                             &offset) != UNW_ESUCCESS) ||
+      if ((__unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
+                               &offset) != UNW_ESUCCESS) ||
           (frameInfo.start_ip + offset > frameInfo.end_ip))
         functionName = ".anonymous.";
       _LIBUNWIND_TRACE_UNWINDING(
@@ -310,7 +316,7 @@ unwind_phase2_forced(unw_context_t *uc, unw_cursor_t *cursor,
                                    "_URC_INSTALL_CONTEXT",
                                    (void *)exception_object);
         // We may get control back if landing pad calls _Unwind_Resume().
-        unw_resume(cursor);
+        __unw_resume(cursor);
         break;
       default:
         // Personality routine returned an unknown result code.
@@ -346,7 +352,7 @@ _Unwind_RaiseException(_Unwind_Exception *exception_object) {
                        (void *)exception_object);
   unw_context_t uc;
   unw_cursor_t cursor;
-  unw_getcontext(&uc);
+  __unw_getcontext(&uc);
 
   // Mark that this is a non-forced unwind, so _Unwind_Resume()
   // can do the right thing.
@@ -380,7 +386,7 @@ _Unwind_Resume(_Unwind_Exception *exception_object) {
   _LIBUNWIND_TRACE_API("_Unwind_Resume(ex_obj=%p)", (void *)exception_object);
   unw_context_t uc;
   unw_cursor_t cursor;
-  unw_getcontext(&uc);
+  __unw_getcontext(&uc);
 
   if (exception_object->private_1 != 0)
     unwind_phase2_forced(&uc, &cursor, exception_object,
@@ -405,7 +411,7 @@ _Unwind_ForcedUnwind(_Unwind_Exception *exception_object,
                        (void *)exception_object, (void *)(uintptr_t)stop);
   unw_context_t uc;
   unw_cursor_t cursor;
-  unw_getcontext(&uc);
+  __unw_getcontext(&uc);
 
   // Mark that this is a forced unwind, so _Unwind_Resume() can do
   // the right thing.
@@ -423,7 +429,7 @@ _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) {
   unw_cursor_t *cursor = (unw_cursor_t *)context;
   unw_proc_info_t frameInfo;
   uintptr_t result = 0;
-  if (unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
+  if (__unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
     result = (uintptr_t)frameInfo.lsda;
   _LIBUNWIND_TRACE_API(
       "_Unwind_GetLanguageSpecificData(context=%p) => 0x%" PRIxPTR,
@@ -444,7 +450,7 @@ _Unwind_GetRegionStart(struct _Unwind_Context *context) {
   unw_cursor_t *cursor = (unw_cursor_t *)context;
   unw_proc_info_t frameInfo;
   uintptr_t result = 0;
-  if (unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
+  if (__unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
     result = (uintptr_t)frameInfo.start_ip;
   _LIBUNWIND_TRACE_API("_Unwind_GetRegionStart(context=%p) => 0x%" PRIxPTR,
                        (void *)context, result);
@@ -469,7 +475,7 @@ _LIBUNWIND_EXPORT uintptr_t
 _Unwind_GetGR(struct _Unwind_Context *context, int index) {
   unw_cursor_t *cursor = (unw_cursor_t *)context;
   unw_word_t result;
-  unw_get_reg(cursor, index, &result);
+  __unw_get_reg(cursor, index, &result);
   _LIBUNWIND_TRACE_API("_Unwind_GetGR(context=%p, reg=%d) => 0x%" PRIxPTR,
                        (void *)context, index, result);
   return (uintptr_t)result;
@@ -482,14 +488,14 @@ _LIBUNWIND_EXPORT void _Unwind_SetGR(struct _Unwind_Context *context, int index,
                        ")",
                        (void *)context, index, value);
   unw_cursor_t *cursor = (unw_cursor_t *)context;
-  unw_set_reg(cursor, index, value);
+  __unw_set_reg(cursor, index, value);
 }
 
 /// Called by personality handler during phase 2 to get instruction pointer.
 _LIBUNWIND_EXPORT uintptr_t _Unwind_GetIP(struct _Unwind_Context *context) {
   unw_cursor_t *cursor = (unw_cursor_t *)context;
   unw_word_t result;
-  unw_get_reg(cursor, UNW_REG_IP, &result);
+  __unw_get_reg(cursor, UNW_REG_IP, &result);
   _LIBUNWIND_TRACE_API("_Unwind_GetIP(context=%p) => 0x%" PRIxPTR,
                        (void *)context, result);
   return (uintptr_t)result;
@@ -503,7 +509,7 @@ _LIBUNWIND_EXPORT void _Unwind_SetIP(struct _Unwind_Context *context,
   _LIBUNWIND_TRACE_API("_Unwind_SetIP(context=%p, value=0x%0" PRIxPTR ")",
                        (void *)context, value);
   unw_cursor_t *cursor = (unw_cursor_t *)context;
-  unw_set_reg(cursor, UNW_REG_IP, value);
+  __unw_set_reg(cursor, UNW_REG_IP, value);
 }
 
 #endif // !defined(_LIBUNWIND_ARM_EHABI) && !defined(__USING_SJLJ_EXCEPTIONS__)
diff --git a/src/UnwindRegistersRestore.S b/src/UnwindRegistersRestore.S
index 389db67579cd..8122bf3e1b2e 100644
--- a/src/UnwindRegistersRestore.S
+++ b/src/UnwindRegistersRestore.S
@@ -1,9 +1,8 @@
 //===-------------------- UnwindRegistersRestore.S ------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //===----------------------------------------------------------------------===//
 
@@ -14,7 +13,7 @@
 #if !defined(__USING_SJLJ_EXCEPTIONS__)
 
 #if defined(__i386__)
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_x866jumptoEv)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_x866jumptoEv)
 #
 # void libunwind::Registers_x86::jumpto()
 #
@@ -61,7 +60,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_x866jumptoEv)
 
 #elif defined(__x86_64__)
 
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind16Registers_x86_646jumptoEv)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind16Registers_x86_646jumptoEv)
 #
 # void libunwind::Registers_x86_64::jumpto()
 #
@@ -130,7 +129,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind16Registers_x86_646jumptoEv)
 
 #elif defined(__powerpc64__)
 
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind15Registers_ppc646jumptoEv)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind15Registers_ppc646jumptoEv)
 //
 // void libunwind::Registers_ppc64::jumpto()
 //
@@ -395,120 +394,120 @@ Lnovec:
 
 #elif defined(__ppc__)
 
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_ppc6jumptoEv)
-;
-; void libunwind::Registers_ppc::jumpto()
-;
-; On entry:
-;  thread_state pointer is in r3
-;
-
-  ; restore integral registerrs
-  ; skip r0 for now
-  ; skip r1 for now
-  lwz     r2, 16(r3)
-  ; skip r3 for now
-  ; skip r4 for now
-  ; skip r5 for now
-  lwz     r6, 32(r3)
-  lwz     r7, 36(r3)
-  lwz     r8, 40(r3)
-  lwz     r9, 44(r3)
-  lwz    r10, 48(r3)
-  lwz    r11, 52(r3)
-  lwz    r12, 56(r3)
-  lwz    r13, 60(r3)
-  lwz    r14, 64(r3)
-  lwz    r15, 68(r3)
-  lwz    r16, 72(r3)
-  lwz    r17, 76(r3)
-  lwz    r18, 80(r3)
-  lwz    r19, 84(r3)
-  lwz    r20, 88(r3)
-  lwz    r21, 92(r3)
-  lwz    r22, 96(r3)
-  lwz    r23,100(r3)
-  lwz    r24,104(r3)
-  lwz    r25,108(r3)
-  lwz    r26,112(r3)
-  lwz    r27,116(r3)
-  lwz    r28,120(r3)
-  lwz    r29,124(r3)
-  lwz    r30,128(r3)
-  lwz    r31,132(r3)
-
-  ; restore float registers
-  lfd    f0, 160(r3)
-  lfd    f1, 168(r3)
-  lfd    f2, 176(r3)
-  lfd    f3, 184(r3)
-  lfd    f4, 192(r3)
-  lfd    f5, 200(r3)
-  lfd    f6, 208(r3)
-  lfd    f7, 216(r3)
-  lfd    f8, 224(r3)
-  lfd    f9, 232(r3)
-  lfd    f10,240(r3)
-  lfd    f11,248(r3)
-  lfd    f12,256(r3)
-  lfd    f13,264(r3)
-  lfd    f14,272(r3)
-  lfd    f15,280(r3)
-  lfd    f16,288(r3)
-  lfd    f17,296(r3)
-  lfd    f18,304(r3)
-  lfd    f19,312(r3)
-  lfd    f20,320(r3)
-  lfd    f21,328(r3)
-  lfd    f22,336(r3)
-  lfd    f23,344(r3)
-  lfd    f24,352(r3)
-  lfd    f25,360(r3)
-  lfd    f26,368(r3)
-  lfd    f27,376(r3)
-  lfd    f28,384(r3)
-  lfd    f29,392(r3)
-  lfd    f30,400(r3)
-  lfd    f31,408(r3)
-
-  ; restore vector registers if any are in use
-  lwz    r5,156(r3)  ; test VRsave
-  cmpwi  r5,0
-  beq    Lnovec
-
-  subi  r4,r1,16
-  rlwinm  r4,r4,0,0,27  ; mask low 4-bits
-  ; r4 is now a 16-byte aligned pointer into the red zone
-  ; the _vectorRegisters may not be 16-byte aligned so copy via red zone temp buffer
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_ppc6jumptoEv)
+//
+// void libunwind::Registers_ppc::jumpto()
+//
+// On entry:
+//  thread_state pointer is in r3
+//
+
+  // restore integral registerrs
+  // skip r0 for now
+  // skip r1 for now
+  lwz     %r2,  16(%r3)
+  // skip r3 for now
+  // skip r4 for now
+  // skip r5 for now
+  lwz     %r6,  32(%r3)
+  lwz     %r7,  36(%r3)
+  lwz     %r8,  40(%r3)
+  lwz     %r9,  44(%r3)
+  lwz     %r10, 48(%r3)
+  lwz     %r11, 52(%r3)
+  lwz     %r12, 56(%r3)
+  lwz     %r13, 60(%r3)
+  lwz     %r14, 64(%r3)
+  lwz     %r15, 68(%r3)
+  lwz     %r16, 72(%r3)
+  lwz     %r17, 76(%r3)
+  lwz     %r18, 80(%r3)
+  lwz     %r19, 84(%r3)
+  lwz     %r20, 88(%r3)
+  lwz     %r21, 92(%r3)
+  lwz     %r22, 96(%r3)
+  lwz     %r23,100(%r3)
+  lwz     %r24,104(%r3)
+  lwz     %r25,108(%r3)
+  lwz     %r26,112(%r3)
+  lwz     %r27,116(%r3)
+  lwz     %r28,120(%r3)
+  lwz     %r29,124(%r3)
+  lwz     %r30,128(%r3)
+  lwz     %r31,132(%r3)
+
+  // restore float registers
+  lfd     %f0, 160(%r3)
+  lfd     %f1, 168(%r3)
+  lfd     %f2, 176(%r3)
+  lfd     %f3, 184(%r3)
+  lfd     %f4, 192(%r3)
+  lfd     %f5, 200(%r3)
+  lfd     %f6, 208(%r3)
+  lfd     %f7, 216(%r3)
+  lfd     %f8, 224(%r3)
+  lfd     %f9, 232(%r3)
+  lfd     %f10,240(%r3)
+  lfd     %f11,248(%r3)
+  lfd     %f12,256(%r3)
+  lfd     %f13,264(%r3)
+  lfd     %f14,272(%r3)
+  lfd     %f15,280(%r3)
+  lfd     %f16,288(%r3)
+  lfd     %f17,296(%r3)
+  lfd     %f18,304(%r3)
+  lfd     %f19,312(%r3)
+  lfd     %f20,320(%r3)
+  lfd     %f21,328(%r3)
+  lfd     %f22,336(%r3)
+  lfd     %f23,344(%r3)
+  lfd     %f24,352(%r3)
+  lfd     %f25,360(%r3)
+  lfd     %f26,368(%r3)
+  lfd     %f27,376(%r3)
+  lfd     %f28,384(%r3)
+  lfd     %f29,392(%r3)
+  lfd     %f30,400(%r3)
+  lfd     %f31,408(%r3)
 
+  // restore vector registers if any are in use
+  lwz     %r5, 156(%r3)       // test VRsave
+  cmpwi   %r5, 0
+  beq     Lnovec
+
+  subi    %r4, %r1, 16
+  rlwinm  %r4, %r4, 0, 0, 27  // mask low 4-bits
+  // r4 is now a 16-byte aligned pointer into the red zone
+  // the _vectorRegisters may not be 16-byte aligned so copy via red zone temp buffer
+ 
 
 #define LOAD_VECTOR_UNALIGNEDl(_index) \
-  andis.  r0,r5,(1<<(15-_index))  @\
-  beq    Ldone  ## _index     @\
-  lwz    r0, 424+_index*16(r3)  @\
-  stw    r0, 0(r4)        @\
-  lwz    r0, 424+_index*16+4(r3)  @\
-  stw    r0, 4(r4)        @\
-  lwz    r0, 424+_index*16+8(r3)  @\
-  stw    r0, 8(r4)        @\
-  lwz    r0, 424+_index*16+12(r3)@\
-  stw    r0, 12(r4)        @\
-  lvx    v ## _index,0,r4    @\
-Ldone  ## _index:
+  andis.  %r0, %r5, (1<<(15-_index))  SEPARATOR \
+  beq     Ldone ## _index             SEPARATOR \
+  lwz     %r0, 424+_index*16(%r3)     SEPARATOR \
+  stw     %r0, 0(%r4)                 SEPARATOR \
+  lwz     %r0, 424+_index*16+4(%r3)   SEPARATOR \
+  stw     %r0, 4(%r4)                 SEPARATOR \
+  lwz     %r0, 424+_index*16+8(%r3)   SEPARATOR \
+  stw     %r0, 8(%r4)                 SEPARATOR \
+  lwz     %r0, 424+_index*16+12(%r3)  SEPARATOR \
+  stw     %r0, 12(%r4)                SEPARATOR \
+  lvx     %v ## _index, 0, %r4        SEPARATOR \
+  Ldone ## _index:
 
 #define LOAD_VECTOR_UNALIGNEDh(_index) \
-  andi.  r0,r5,(1<<(31-_index))  @\
-  beq    Ldone  ## _index    @\
-  lwz    r0, 424+_index*16(r3)  @\
-  stw    r0, 0(r4)        @\
-  lwz    r0, 424+_index*16+4(r3)  @\
-  stw    r0, 4(r4)        @\
-  lwz    r0, 424+_index*16+8(r3)  @\
-  stw    r0, 8(r4)        @\
-  lwz    r0, 424+_index*16+12(r3)@\
-  stw    r0, 12(r4)        @\
-  lvx    v ## _index,0,r4    @\
-  Ldone  ## _index:
+  andi.   %r0, %r5, (1<<(31-_index))  SEPARATOR \
+  beq     Ldone ## _index             SEPARATOR \
+  lwz     %r0, 424+_index*16(%r3)     SEPARATOR \
+  stw     %r0, 0(%r4)                 SEPARATOR \
+  lwz     %r0, 424+_index*16+4(%r3)   SEPARATOR \
+  stw     %r0, 4(%r4)                 SEPARATOR \
+  lwz     %r0, 424+_index*16+8(%r3)   SEPARATOR \
+  stw     %r0, 8(%r4)                 SEPARATOR \
+  lwz     %r0, 424+_index*16+12(%r3)  SEPARATOR \
+  stw     %r0, 12(%r4)                SEPARATOR \
+  lvx     %v ## _index, 0, %r4        SEPARATOR \
+  Ldone ## _index:
 
 
   LOAD_VECTOR_UNALIGNEDl(0)
@@ -545,17 +544,17 @@ Ldone  ## _index:
   LOAD_VECTOR_UNALIGNEDh(31)
 
 Lnovec:
-  lwz    r0, 136(r3) ; __cr
-  mtocrf  255,r0
-  lwz    r0, 148(r3) ; __ctr
-  mtctr  r0
-  lwz    r0, 0(r3)  ; __ssr0
-  mtctr  r0
-  lwz    r0, 8(r3)  ; do r0 now
-  lwz    r5,28(r3)  ; do r5 now
-  lwz    r4,24(r3)  ; do r4 now
-  lwz    r1,12(r3)  ; do sp now
-  lwz    r3,20(r3)  ; do r3 last
+  lwz     %r0, 136(%r3)   // __cr
+  mtcr    %r0
+  lwz     %r0, 148(%r3)   // __ctr
+  mtctr   %r0
+  lwz     %r0,   0(%r3)   // __ssr0
+  mtctr   %r0
+  lwz     %r0,   8(%r3)   // do r0 now
+  lwz     %r5,  28(%r3)   // do r5 now
+  lwz     %r4,  24(%r3)   // do r4 now
+  lwz     %r1,  12(%r3)   // do sp now
+  lwz     %r3,  20(%r3)   // do r3 last
   bctr
 
 #elif defined(__arm64__) || defined(__aarch64__)
@@ -567,7 +566,7 @@ Lnovec:
 //  thread_state pointer is in x0
 //
   .p2align 2
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind15Registers_arm646jumptoEv)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind15Registers_arm646jumptoEv)
   // skip restore of x0,x1 for now
   ldp    x2, x3,  [x0, #0x010]
   ldp    x4, x5,  [x0, #0x020]
@@ -576,7 +575,8 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind15Registers_arm646jumptoEv)
   ldp    x10,x11, [x0, #0x050]
   ldp    x12,x13, [x0, #0x060]
   ldp    x14,x15, [x0, #0x070]
-  ldp    x16,x17, [x0, #0x080]
+  // x16 and x17 were clobbered by the call into the unwinder, so no point in
+  // restoring them.
   ldp    x18,x19, [x0, #0x090]
   ldp    x20,x21, [x0, #0x0A0]
   ldp    x22,x23, [x0, #0x0B0]
@@ -584,8 +584,6 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind15Registers_arm646jumptoEv)
   ldp    x26,x27, [x0, #0x0D0]
   ldp    x28,x29, [x0, #0x0E0]
   ldr    x30,     [x0, #0x100]  // restore pc into lr
-  ldr    x1,      [x0, #0x0F8]
-  mov    sp,x1                  // restore sp
 
   ldp    d0, d1,  [x0, #0x110]
   ldp    d2, d3,  [x0, #0x120]
@@ -605,12 +603,21 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind15Registers_arm646jumptoEv)
   ldr    d30,     [x0, #0x200]
   ldr    d31,     [x0, #0x208]
 
+  // Finally, restore sp. This must be done after the the last read from the
+  // context struct, because it is allocated on the stack, and an exception
+  // could clobber the de-allocated portion of the stack after sp has been
+  // restored.
+  ldr    x16,     [x0, #0x0F8]
   ldp    x0, x1,  [x0, #0x000]  // restore x0,x1
+  mov    sp,x16                 // restore sp
   ret    x30                    // jump to pc
 
 #elif defined(__arm__) && !defined(__APPLE__)
 
 #if !defined(__ARM_ARCH_ISA_ARM)
+#if (__ARM_ARCH_ISA_THUMB == 2)
+  .syntax unified
+#endif
   .thumb
 #endif
 
@@ -621,7 +628,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind15Registers_arm646jumptoEv)
 @  thread_state pointer is in r0
 @
   .p2align 2
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm20restoreCoreAndJumpToEv)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_arm20restoreCoreAndJumpToEv)
 #if !defined(__ARM_ARCH_ISA_ARM) && __ARM_ARCH_ISA_THUMB == 1
   @ r8-r11: ldm into r1-r4, then mov to r8-r11
   adds r0, #0x20
@@ -659,7 +666,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm20restoreCoreAndJu
 #if defined(__ELF__)
   .fpu vfpv3-d16
 #endif
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm19restoreVFPWithFLDMDEPy)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_arm19restoreVFPWithFLDMDEPv)
   @ VFP and iwMMX instructions are only available when compiling with the flags
   @ that enable them. We do not want to do that in the library (because we do not
   @ want the compiler to generate instructions that access those) but this is
@@ -680,7 +687,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm19restoreVFPWithFL
 #if defined(__ELF__)
   .fpu vfpv3-d16
 #endif
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm19restoreVFPWithFLDMXEPy)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_arm19restoreVFPWithFLDMXEPv)
   vldmia r0, {d0-d15} @ fldmiax is deprecated in ARMv7+ and now behaves like vldmia
   JMP(lr)
 
@@ -694,7 +701,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm19restoreVFPWithFL
 #if defined(__ELF__)
   .fpu vfpv3
 #endif
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm12restoreVFPv3EPy)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_arm12restoreVFPv3EPv)
   vldmia r0, {d16-d31}
   JMP(lr)
 
@@ -710,7 +717,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm12restoreVFPv3EPy)
 #if defined(__ELF__)
   .arch armv5te
 #endif
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm12restoreiWMMXEPy)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_arm12restoreiWMMXEPv)
   ldcl p1, cr0, [r0], #8  @ wldrd wR0, [r0], #8
   ldcl p1, cr1, [r0], #8  @ wldrd wR1, [r0], #8
   ldcl p1, cr2, [r0], #8  @ wldrd wR2, [r0], #8
@@ -739,7 +746,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm12restoreiWMMXEPy)
 #if defined(__ELF__)
   .arch armv5te
 #endif
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm19restoreiWMMXControlEPj)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_arm19restoreiWMMXControlEPj)
   ldc2 p1, cr8, [r0], #4  @ wldrw wCGR0, [r0], #4
   ldc2 p1, cr9, [r0], #4  @ wldrw wCGR1, [r0], #4
   ldc2 p1, cr10, [r0], #4  @ wldrw wCGR2, [r0], #4
@@ -750,7 +757,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm19restoreiWMMXCont
 
 #elif defined(__or1k__)
 
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind14Registers_or1k6jumptoEv)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind14Registers_or1k6jumptoEv)
 #
 # void libunwind::Registers_or1k::jumpto()
 #
@@ -809,7 +816,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind14Registers_or1k6jumptoEv)
 // On entry:
 //  thread state pointer is in a0 ($4)
 //
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind18Registers_mips_o326jumptoEv)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind18Registers_mips_o326jumptoEv)
   .set push
   .set noat
   .set noreorder
@@ -918,7 +925,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind18Registers_mips_o326jumptoEv)
 // On entry:
 //  thread state pointer is in a0 ($4)
 //
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind21Registers_mips_newabi6jumptoEv)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind21Registers_mips_newabi6jumptoEv)
   .set push
   .set noat
   .set noreorder
@@ -1008,7 +1015,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind21Registers_mips_newabi6jumptoEv)
 // On entry:
 //  thread_state pointer is in o0
 //
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind15Registers_sparc6jumptoEv)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind15Registers_sparc6jumptoEv)
   ta 3
   ldd [%o0 + 64],  %l0
   ldd [%o0 + 72],  %l2
diff --git a/src/UnwindRegistersSave.S b/src/UnwindRegistersSave.S
index 48ecb0aec70f..54505e53bac7 100644
--- a/src/UnwindRegistersSave.S
+++ b/src/UnwindRegistersSave.S
@@ -1,9 +1,8 @@
 //===------------------------ UnwindRegistersSave.S -----------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //===----------------------------------------------------------------------===//
 
@@ -16,7 +15,7 @@
 #if defined(__i386__)
 
 #
-# extern int unw_getcontext(unw_context_t* thread_state)
+# extern int __unw_getcontext(unw_context_t* thread_state)
 #
 # On entry:
 #   +                       +
@@ -27,7 +26,7 @@
 #   +-----------------------+   <-- SP
 #   +                       +
 #
-DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
+DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
   push  %eax
   movl  8(%esp), %eax
   movl  %ebx,  4(%eax)
@@ -57,12 +56,12 @@ DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
 #elif defined(__x86_64__)
 
 #
-# extern int unw_getcontext(unw_context_t* thread_state)
+# extern int __unw_getcontext(unw_context_t* thread_state)
 #
 # On entry:
 #  thread_state pointer is in rdi
 #
-DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
+DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
 #if defined(_WIN64)
 #define PTR %rcx
 #define TMP %rdx
@@ -119,12 +118,12 @@ DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
 #elif defined(__mips__) && defined(_ABIO32) && _MIPS_SIM == _ABIO32
 
 #
-# extern int unw_getcontext(unw_context_t* thread_state)
+# extern int __unw_getcontext(unw_context_t* thread_state)
 #
 # On entry:
 #  thread_state pointer is in a0 ($4)
 #
-DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
+DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
   .set push
   .set noat
   .set noreorder
@@ -228,12 +227,12 @@ DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
 #elif defined(__mips64)
 
 #
-# extern int unw_getcontext(unw_context_t* thread_state)
+# extern int __unw_getcontext(unw_context_t* thread_state)
 #
 # On entry:
 #  thread_state pointer is in a0 ($4)
 #
-DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
+DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
   .set push
   .set noat
   .set noreorder
@@ -318,21 +317,21 @@ DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
 # elif defined(__mips__)
 
 #
-# extern int unw_getcontext(unw_context_t* thread_state)
+# extern int __unw_getcontext(unw_context_t* thread_state)
 #
 # Just trap for the time being.
-DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
+DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
   teq $0, $0
 
 #elif defined(__powerpc64__)
 
 //
-// extern int unw_getcontext(unw_context_t* thread_state)
+// extern int __unw_getcontext(unw_context_t* thread_state)
 //
 // On entry:
 //  thread_state pointer is in r3
 //
-DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
+DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
 
 // store register (GPR)
 #define PPC64_STR(n) \
@@ -557,157 +556,157 @@ DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
 
 #elif defined(__ppc__)
 
-;
-; extern int unw_getcontext(unw_context_t* thread_state)
-;
-; On entry:
-;  thread_state pointer is in r3
-;
-DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
-  stw    r0,  8(r3)
-  mflr  r0
-  stw    r0,  0(r3)  ; store lr as ssr0
-  stw    r1, 12(r3)
-  stw    r2, 16(r3)
-  stw    r3, 20(r3)
-  stw    r4, 24(r3)
-  stw    r5, 28(r3)
-  stw    r6, 32(r3)
-  stw    r7, 36(r3)
-  stw    r8, 40(r3)
-  stw    r9, 44(r3)
-  stw     r10, 48(r3)
-  stw     r11, 52(r3)
-  stw     r12, 56(r3)
-  stw     r13, 60(r3)
-  stw     r14, 64(r3)
-  stw     r15, 68(r3)
-  stw     r16, 72(r3)
-  stw     r17, 76(r3)
-  stw     r18, 80(r3)
-  stw     r19, 84(r3)
-  stw     r20, 88(r3)
-  stw     r21, 92(r3)
-  stw     r22, 96(r3)
-  stw     r23,100(r3)
-  stw     r24,104(r3)
-  stw     r25,108(r3)
-  stw     r26,112(r3)
-  stw     r27,116(r3)
-  stw     r28,120(r3)
-  stw     r29,124(r3)
-  stw     r30,128(r3)
-  stw     r31,132(r3)
-
-  ; save VRSave register
-  mfspr  r0,256
-  stw    r0,156(r3)
-  ; save CR registers
-  mfcr  r0
-  stw    r0,136(r3)
-  ; save CTR register
-  mfctr  r0
-  stw    r0,148(r3)
-
-  ; save float registers
-  stfd    f0, 160(r3)
-  stfd    f1, 168(r3)
-  stfd    f2, 176(r3)
-  stfd    f3, 184(r3)
-  stfd    f4, 192(r3)
-  stfd    f5, 200(r3)
-  stfd    f6, 208(r3)
-  stfd    f7, 216(r3)
-  stfd    f8, 224(r3)
-  stfd    f9, 232(r3)
-  stfd    f10,240(r3)
-  stfd    f11,248(r3)
-  stfd    f12,256(r3)
-  stfd    f13,264(r3)
-  stfd    f14,272(r3)
-  stfd    f15,280(r3)
-  stfd    f16,288(r3)
-  stfd    f17,296(r3)
-  stfd    f18,304(r3)
-  stfd    f19,312(r3)
-  stfd    f20,320(r3)
-  stfd    f21,328(r3)
-  stfd    f22,336(r3)
-  stfd    f23,344(r3)
-  stfd    f24,352(r3)
-  stfd    f25,360(r3)
-  stfd    f26,368(r3)
-  stfd    f27,376(r3)
-  stfd    f28,384(r3)
-  stfd    f29,392(r3)
-  stfd    f30,400(r3)
-  stfd    f31,408(r3)
-
-
-  ; save vector registers
-
-  subi  r4,r1,16
-  rlwinm  r4,r4,0,0,27  ; mask low 4-bits
-  ; r4 is now a 16-byte aligned pointer into the red zone
+//
+// extern int unw_getcontext(unw_context_t* thread_state)
+//
+// On entry:
+//  thread_state pointer is in r3
+//
+DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
+  stw     %r0,   8(%r3)
+  mflr    %r0
+  stw     %r0,   0(%r3) // store lr as ssr0
+  stw     %r1,  12(%r3)
+  stw     %r2,  16(%r3)
+  stw     %r3,  20(%r3)
+  stw     %r4,  24(%r3)
+  stw     %r5,  28(%r3)
+  stw     %r6,  32(%r3)
+  stw     %r7,  36(%r3)
+  stw     %r8,  40(%r3)
+  stw     %r9,  44(%r3)
+  stw     %r10, 48(%r3)
+  stw     %r11, 52(%r3)
+  stw     %r12, 56(%r3)
+  stw     %r13, 60(%r3)
+  stw     %r14, 64(%r3)
+  stw     %r15, 68(%r3)
+  stw     %r16, 72(%r3)
+  stw     %r17, 76(%r3)
+  stw     %r18, 80(%r3)
+  stw     %r19, 84(%r3)
+  stw     %r20, 88(%r3)
+  stw     %r21, 92(%r3)
+  stw     %r22, 96(%r3)
+  stw     %r23,100(%r3)
+  stw     %r24,104(%r3)
+  stw     %r25,108(%r3)
+  stw     %r26,112(%r3)
+  stw     %r27,116(%r3)
+  stw     %r28,120(%r3)
+  stw     %r29,124(%r3)
+  stw     %r30,128(%r3)
+  stw     %r31,132(%r3)
+
+  // save VRSave register
+  mfspr   %r0, 256
+  stw     %r0, 156(%r3)
+  // save CR registers
+  mfcr    %r0
+  stw     %r0, 136(%r3)
+  // save CTR register
+  mfctr   %r0
+  stw     %r0, 148(%r3)
+
+  // save float registers
+  stfd    %f0, 160(%r3)
+  stfd    %f1, 168(%r3)
+  stfd    %f2, 176(%r3)
+  stfd    %f3, 184(%r3)
+  stfd    %f4, 192(%r3)
+  stfd    %f5, 200(%r3)
+  stfd    %f6, 208(%r3)
+  stfd    %f7, 216(%r3)
+  stfd    %f8, 224(%r3)
+  stfd    %f9, 232(%r3)
+  stfd    %f10,240(%r3)
+  stfd    %f11,248(%r3)
+  stfd    %f12,256(%r3)
+  stfd    %f13,264(%r3)
+  stfd    %f14,272(%r3)
+  stfd    %f15,280(%r3)
+  stfd    %f16,288(%r3)
+  stfd    %f17,296(%r3)
+  stfd    %f18,304(%r3)
+  stfd    %f19,312(%r3)
+  stfd    %f20,320(%r3)
+  stfd    %f21,328(%r3)
+  stfd    %f22,336(%r3)
+  stfd    %f23,344(%r3)
+  stfd    %f24,352(%r3)
+  stfd    %f25,360(%r3)
+  stfd    %f26,368(%r3)
+  stfd    %f27,376(%r3)
+  stfd    %f28,384(%r3)
+  stfd    %f29,392(%r3)
+  stfd    %f30,400(%r3)
+  stfd    %f31,408(%r3)
+
+
+  // save vector registers
+
+  subi    %r4, %r1, 16
+  rlwinm  %r4, %r4, 0, 0, 27  // mask low 4-bits
+  // r4 is now a 16-byte aligned pointer into the red zone
 
 #define SAVE_VECTOR_UNALIGNED(_vec, _offset) \
-  stvx  _vec,0,r4           @\
-  lwz    r5, 0(r4)          @\
-  stw    r5, _offset(r3)    @\
-  lwz    r5, 4(r4)          @\
-  stw    r5, _offset+4(r3)  @\
-  lwz    r5, 8(r4)          @\
-  stw    r5, _offset+8(r3)  @\
-  lwz    r5, 12(r4)         @\
-  stw    r5, _offset+12(r3)
-
-  SAVE_VECTOR_UNALIGNED( v0, 424+0x000)
-  SAVE_VECTOR_UNALIGNED( v1, 424+0x010)
-  SAVE_VECTOR_UNALIGNED( v2, 424+0x020)
-  SAVE_VECTOR_UNALIGNED( v3, 424+0x030)
-  SAVE_VECTOR_UNALIGNED( v4, 424+0x040)
-  SAVE_VECTOR_UNALIGNED( v5, 424+0x050)
-  SAVE_VECTOR_UNALIGNED( v6, 424+0x060)
-  SAVE_VECTOR_UNALIGNED( v7, 424+0x070)
-  SAVE_VECTOR_UNALIGNED( v8, 424+0x080)
-  SAVE_VECTOR_UNALIGNED( v9, 424+0x090)
-  SAVE_VECTOR_UNALIGNED(v10, 424+0x0A0)
-  SAVE_VECTOR_UNALIGNED(v11, 424+0x0B0)
-  SAVE_VECTOR_UNALIGNED(v12, 424+0x0C0)
-  SAVE_VECTOR_UNALIGNED(v13, 424+0x0D0)
-  SAVE_VECTOR_UNALIGNED(v14, 424+0x0E0)
-  SAVE_VECTOR_UNALIGNED(v15, 424+0x0F0)
-  SAVE_VECTOR_UNALIGNED(v16, 424+0x100)
-  SAVE_VECTOR_UNALIGNED(v17, 424+0x110)
-  SAVE_VECTOR_UNALIGNED(v18, 424+0x120)
-  SAVE_VECTOR_UNALIGNED(v19, 424+0x130)
-  SAVE_VECTOR_UNALIGNED(v20, 424+0x140)
-  SAVE_VECTOR_UNALIGNED(v21, 424+0x150)
-  SAVE_VECTOR_UNALIGNED(v22, 424+0x160)
-  SAVE_VECTOR_UNALIGNED(v23, 424+0x170)
-  SAVE_VECTOR_UNALIGNED(v24, 424+0x180)
-  SAVE_VECTOR_UNALIGNED(v25, 424+0x190)
-  SAVE_VECTOR_UNALIGNED(v26, 424+0x1A0)
-  SAVE_VECTOR_UNALIGNED(v27, 424+0x1B0)
-  SAVE_VECTOR_UNALIGNED(v28, 424+0x1C0)
-  SAVE_VECTOR_UNALIGNED(v29, 424+0x1D0)
-  SAVE_VECTOR_UNALIGNED(v30, 424+0x1E0)
-  SAVE_VECTOR_UNALIGNED(v31, 424+0x1F0)
-
-  li  r3, 0    ; return UNW_ESUCCESS
+  stvx    _vec, 0, %r4          SEPARATOR \
+  lwz     %r5, 0(%r4)           SEPARATOR \
+  stw     %r5, _offset(%r3)     SEPARATOR \
+  lwz     %r5, 4(%r4)           SEPARATOR \
+  stw     %r5, _offset+4(%r3)   SEPARATOR \
+  lwz     %r5, 8(%r4)           SEPARATOR \
+  stw     %r5, _offset+8(%r3)   SEPARATOR \
+  lwz     %r5, 12(%r4)          SEPARATOR \
+  stw     %r5, _offset+12(%r3)
+
+  SAVE_VECTOR_UNALIGNED( %v0, 424+0x000)
+  SAVE_VECTOR_UNALIGNED( %v1, 424+0x010)
+  SAVE_VECTOR_UNALIGNED( %v2, 424+0x020)
+  SAVE_VECTOR_UNALIGNED( %v3, 424+0x030)
+  SAVE_VECTOR_UNALIGNED( %v4, 424+0x040)
+  SAVE_VECTOR_UNALIGNED( %v5, 424+0x050)
+  SAVE_VECTOR_UNALIGNED( %v6, 424+0x060)
+  SAVE_VECTOR_UNALIGNED( %v7, 424+0x070)
+  SAVE_VECTOR_UNALIGNED( %v8, 424+0x080)
+  SAVE_VECTOR_UNALIGNED( %v9, 424+0x090)
+  SAVE_VECTOR_UNALIGNED(%v10, 424+0x0A0)
+  SAVE_VECTOR_UNALIGNED(%v11, 424+0x0B0)
+  SAVE_VECTOR_UNALIGNED(%v12, 424+0x0C0)
+  SAVE_VECTOR_UNALIGNED(%v13, 424+0x0D0)
+  SAVE_VECTOR_UNALIGNED(%v14, 424+0x0E0)
+  SAVE_VECTOR_UNALIGNED(%v15, 424+0x0F0)
+  SAVE_VECTOR_UNALIGNED(%v16, 424+0x100)
+  SAVE_VECTOR_UNALIGNED(%v17, 424+0x110)
+  SAVE_VECTOR_UNALIGNED(%v18, 424+0x120)
+  SAVE_VECTOR_UNALIGNED(%v19, 424+0x130)
+  SAVE_VECTOR_UNALIGNED(%v20, 424+0x140)
+  SAVE_VECTOR_UNALIGNED(%v21, 424+0x150)
+  SAVE_VECTOR_UNALIGNED(%v22, 424+0x160)
+  SAVE_VECTOR_UNALIGNED(%v23, 424+0x170)
+  SAVE_VECTOR_UNALIGNED(%v24, 424+0x180)
+  SAVE_VECTOR_UNALIGNED(%v25, 424+0x190)
+  SAVE_VECTOR_UNALIGNED(%v26, 424+0x1A0)
+  SAVE_VECTOR_UNALIGNED(%v27, 424+0x1B0)
+  SAVE_VECTOR_UNALIGNED(%v28, 424+0x1C0)
+  SAVE_VECTOR_UNALIGNED(%v29, 424+0x1D0)
+  SAVE_VECTOR_UNALIGNED(%v30, 424+0x1E0)
+  SAVE_VECTOR_UNALIGNED(%v31, 424+0x1F0)
+
+  li      %r3, 0  // return UNW_ESUCCESS
   blr
 
 
 #elif defined(__arm64__) || defined(__aarch64__)
 
 //
-// extern int unw_getcontext(unw_context_t* thread_state)
+// extern int __unw_getcontext(unw_context_t* thread_state)
 //
 // On entry:
 //  thread_state pointer is in x0
 //
   .p2align 2
-DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
+DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
   stp    x0, x1,  [x0, #0x000]
   stp    x2, x3,  [x0, #0x010]
   stp    x4, x5,  [x0, #0x020]
@@ -751,11 +750,14 @@ DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
 #elif defined(__arm__) && !defined(__APPLE__)
 
 #if !defined(__ARM_ARCH_ISA_ARM)
+#if (__ARM_ARCH_ISA_THUMB == 2)
+  .syntax unified
+#endif
   .thumb
 #endif
 
 @
-@ extern int unw_getcontext(unw_context_t* thread_state)
+@ extern int __unw_getcontext(unw_context_t* thread_state)
 @
 @ On entry:
 @  thread_state pointer is in r0
@@ -764,10 +766,10 @@ DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
 @ EHABI #7.4.5 notes that in general all VRS registers should be restored
 @ however this is very hard to do for VFP registers because it is unknown
 @ to the library how many registers are implemented by the architecture.
-@ Instead, VFP registers are demand saved by logic external to unw_getcontext.
+@ Instead, VFP registers are demand saved by logic external to __unw_getcontext.
 @
   .p2align 2
-DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
+DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
 #if !defined(__ARM_ARCH_ISA_ARM) && __ARM_ARCH_ISA_THUMB == 1
   stm r0!, {r0-r7}
   mov r1, r8
@@ -808,7 +810,7 @@ DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
 #if defined(__ELF__)
   .fpu vfpv3-d16
 #endif
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm16saveVFPWithFSTMDEPy)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_arm16saveVFPWithFSTMDEPv)
   vstmia r0, {d0-d15}
   JMP(lr)
 
@@ -822,7 +824,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm16saveVFPWithFSTMD
 #if defined(__ELF__)
   .fpu vfpv3-d16
 #endif
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm16saveVFPWithFSTMXEPy)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_arm16saveVFPWithFSTMXEPv)
   vstmia r0, {d0-d15} @ fstmiax is deprecated in ARMv7+ and now behaves like vstmia
   JMP(lr)
 
@@ -836,7 +838,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm16saveVFPWithFSTMX
 #if defined(__ELF__)
   .fpu vfpv3
 #endif
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm9saveVFPv3EPy)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_arm9saveVFPv3EPv)
   @ VFP and iwMMX instructions are only available when compiling with the flags
   @ that enable them. We do not want to do that in the library (because we do not
   @ want the compiler to generate instructions that access those) but this is
@@ -859,7 +861,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm9saveVFPv3EPy)
 #if defined(__ELF__)
   .arch armv5te
 #endif
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm9saveiWMMXEPy)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_arm9saveiWMMXEPv)
   stcl p1, cr0, [r0], #8  @ wstrd wR0, [r0], #8
   stcl p1, cr1, [r0], #8  @ wstrd wR1, [r0], #8
   stcl p1, cr2, [r0], #8  @ wstrd wR2, [r0], #8
@@ -888,7 +890,7 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm9saveiWMMXEPy)
 #if defined(__ELF__)
   .arch armv5te
 #endif
-DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm16saveiWMMXControlEPj)
+DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_arm16saveiWMMXControlEPj)
   stc2 p1, cr8, [r0], #4  @ wstrw wCGR0, [r0], #4
   stc2 p1, cr9, [r0], #4  @ wstrw wCGR1, [r0], #4
   stc2 p1, cr10, [r0], #4  @ wstrw wCGR2, [r0], #4
@@ -900,12 +902,12 @@ DEFINE_LIBUNWIND_PRIVATE_FUNCTION(_ZN9libunwind13Registers_arm16saveiWMMXControl
 #elif defined(__or1k__)
 
 #
-# extern int unw_getcontext(unw_context_t* thread_state)
+# extern int __unw_getcontext(unw_context_t* thread_state)
 #
 # On entry:
 #  thread_state pointer is in r3
 #
-DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
+DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
   l.sw       0(r3), r0
   l.sw       4(r3), r1
   l.sw       8(r3), r2
@@ -946,12 +948,12 @@ DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
 #elif defined(__sparc__)
 
 #
-# extern int unw_getcontext(unw_context_t* thread_state)
+# extern int __unw_getcontext(unw_context_t* thread_state)
 #
 # On entry:
 #  thread_state pointer is in o0
 #
-DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
+DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
   ta 3
   add %o7, 8, %o7
   std %g0, [%o0 +   0]
@@ -973,6 +975,9 @@ DEFINE_LIBUNWIND_FUNCTION(unw_getcontext)
   jmp %o7
    clr %o0                   // return UNW_ESUCCESS
 #endif
+
+  WEAK_ALIAS(__unw_getcontext, unw_getcontext)
+
 #endif /* !defined(__USING_SJLJ_EXCEPTIONS__) */
 
 NO_EXEC_STACK_DIRECTIVE
diff --git a/src/Unwind_AppleExtras.cpp b/src/Unwind_AppleExtras.cpp
index 39f379c5298c..248d99570e94 100644
--- a/src/Unwind_AppleExtras.cpp
+++ b/src/Unwind_AppleExtras.cpp
@@ -1,9 +1,8 @@
 //===--------------------- Unwind_AppleExtras.cpp -------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 //===----------------------------------------------------------------------===//
diff --git a/src/assembly.h b/src/assembly.h
index 2df930214fae..7132b6c561b0 100644
--- a/src/assembly.h
+++ b/src/assembly.h
@@ -1,9 +1,8 @@
 /* ===-- assembly.h - libUnwind assembler support macros -------------------===
  *
- *                     The LLVM Compiler Infrastructure
- *
- * This file is dual licensed under the MIT and the University of Illinois Open
- * Source Licenses. See LICENSE.TXT for details.
+ * 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
  *
  * ===----------------------------------------------------------------------===
  *
@@ -29,14 +28,26 @@
 #ifdef _ARCH_PWR8
 #define PPC64_HAS_VMX
 #endif
-#elif defined(__POWERPC__) || defined(__powerpc__) || defined(__ppc__)
-#define SEPARATOR @
 #elif defined(__arm64__)
 #define SEPARATOR %%
 #else
 #define SEPARATOR ;
 #endif
 
+#if defined(__powerpc64__) && (!defined(_CALL_ELF) || _CALL_ELF == 1)
+#define PPC64_OPD1 .section .opd,"aw",@progbits SEPARATOR
+#define PPC64_OPD2 SEPARATOR \
+  .p2align 3 SEPARATOR \
+  .quad .Lfunc_begin0 SEPARATOR \
+  .quad .TOC.@tocbase SEPARATOR \
+  .quad 0 SEPARATOR \
+  .text SEPARATOR \
+.Lfunc_begin0:
+#else
+#define PPC64_OPD1
+#define PPC64_OPD2
+#endif
+
 #define GLUE2(a, b) a ## b
 #define GLUE(a, b) GLUE2(a, b)
 #define SYMBOL_NAME(name) GLUE(__USER_LABEL_PREFIX__, name)
@@ -46,6 +57,12 @@
 #define SYMBOL_IS_FUNC(name)
 #define EXPORT_SYMBOL(name)
 #define HIDDEN_SYMBOL(name) .private_extern name
+#define WEAK_SYMBOL(name) .weak_reference name
+#define WEAK_ALIAS(name, aliasname)                                            \
+  .globl SYMBOL_NAME(aliasname) SEPARATOR                                      \
+  WEAK_SYMBOL(aliasname) SEPARATOR                                             \
+  SYMBOL_NAME(aliasname) = SYMBOL_NAME(name)
+
 #define NO_EXEC_STACK_DIRECTIVE
 
 #elif defined(__ELF__)
@@ -57,6 +74,10 @@
 #endif
 #define EXPORT_SYMBOL(name)
 #define HIDDEN_SYMBOL(name) .hidden name
+#define WEAK_SYMBOL(name) .weak name
+#define WEAK_ALIAS(name, aliasname)                                            \
+  WEAK_SYMBOL(aliasname) SEPARATOR                                             \
+  SYMBOL_NAME(aliasname) = SYMBOL_NAME(name)
 
 #if defined(__GNU__) || defined(__FreeBSD__) || defined(__Fuchsia__) || \
     defined(__linux__)
@@ -72,9 +93,9 @@
     .scl 2 SEPARATOR                                                           \
     .type 32 SEPARATOR                                                         \
   .endef
-#define EXPORT_SYMBOL2(name)                              \
-  .section .drectve,"yn" SEPARATOR                        \
-  .ascii "-export:", #name, "\0" SEPARATOR                \
+#define EXPORT_SYMBOL2(name)                                                   \
+  .section .drectve,"yn" SEPARATOR                                             \
+  .ascii "-export:", #name, "\0" SEPARATOR                                     \
   .text
 #if defined(_LIBUNWIND_DISABLE_VISIBILITY_ANNOTATIONS)
 #define EXPORT_SYMBOL(name)
@@ -83,6 +104,23 @@
 #endif
 #define HIDDEN_SYMBOL(name)
 
+#if defined(__MINGW32__)
+#define WEAK_ALIAS(name, aliasname)                                            \
+  .globl SYMBOL_NAME(aliasname) SEPARATOR                                      \
+  EXPORT_SYMBOL(aliasname) SEPARATOR                                           \
+  SYMBOL_NAME(aliasname) = SYMBOL_NAME(name)
+#else
+#define WEAK_ALIAS3(name, aliasname)                                           \
+  .section .drectve,"yn" SEPARATOR                                             \
+  .ascii "-alternatename:", #aliasname, "=", #name, "\0" SEPARATOR             \
+  .text
+#define WEAK_ALIAS2(name, aliasname)                                           \
+  WEAK_ALIAS3(name, aliasname)
+#define WEAK_ALIAS(name, aliasname)                                            \
+  EXPORT_SYMBOL(SYMBOL_NAME(aliasname)) SEPARATOR                              \
+  WEAK_ALIAS2(SYMBOL_NAME(name), SYMBOL_NAME(aliasname))
+#endif
+
 #define NO_EXEC_STACK_DIRECTIVE
 
 #elif defined(__sparc__)
@@ -93,17 +131,13 @@
 
 #endif
 
-#define DEFINE_LIBUNWIND_FUNCTION(name)                   \
-  .globl SYMBOL_NAME(name) SEPARATOR                      \
-  EXPORT_SYMBOL(name) SEPARATOR                           \
-  SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR             \
-  SYMBOL_NAME(name):
-
-#define DEFINE_LIBUNWIND_PRIVATE_FUNCTION(name)           \
-  .globl SYMBOL_NAME(name) SEPARATOR                      \
-  HIDDEN_SYMBOL(SYMBOL_NAME(name)) SEPARATOR              \
-  SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR             \
-  SYMBOL_NAME(name):
+#define DEFINE_LIBUNWIND_FUNCTION(name)                                        \
+  .globl SYMBOL_NAME(name) SEPARATOR                                           \
+  HIDDEN_SYMBOL(SYMBOL_NAME(name)) SEPARATOR                                   \
+  SYMBOL_IS_FUNC(SYMBOL_NAME(name)) SEPARATOR                                  \
+  PPC64_OPD1                                                                   \
+  SYMBOL_NAME(name):                                                           \
+  PPC64_OPD2
 
 #if defined(__arm__)
 #if !defined(__ARM_ARCH)
diff --git a/src/config.h b/src/config.h
index fc7fd646707e..09bb261647ca 100644
--- a/src/config.h
+++ b/src/config.h
@@ -1,9 +1,8 @@
 //===----------------------------- config.h -------------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 //  Defines macros used within libunwind project.
@@ -63,6 +62,35 @@
   #endif
 #endif
 
+#define STR(a) #a
+#define XSTR(a) STR(a)
+#define SYMBOL_NAME(name) XSTR(__USER_LABEL_PREFIX__) #name
+
+#if defined(__APPLE__)
+#define _LIBUNWIND_WEAK_ALIAS(name, aliasname)                                 \
+  __asm__(".globl " SYMBOL_NAME(aliasname));                                   \
+  __asm__(SYMBOL_NAME(aliasname) " = " SYMBOL_NAME(name));                     \
+  extern "C" _LIBUNWIND_EXPORT __typeof(name) aliasname                        \
+      __attribute__((weak_import));
+#elif defined(__ELF__)
+#define _LIBUNWIND_WEAK_ALIAS(name, aliasname)                                 \
+  extern "C" _LIBUNWIND_EXPORT __typeof(name) aliasname                        \
+      __attribute__((weak, alias(#name)));
+#elif defined(_WIN32)
+#if defined(__MINGW32__)
+#define _LIBUNWIND_WEAK_ALIAS(name, aliasname)                                 \
+  extern "C" _LIBUNWIND_EXPORT __typeof(name) aliasname                        \
+      __attribute__((alias(#name)));
+#else
+#define _LIBUNWIND_WEAK_ALIAS(name, aliasname)                                 \
+  __pragma(comment(linker, "/alternatename:" SYMBOL_NAME(aliasname) "="        \
+                                             SYMBOL_NAME(name)))               \
+  extern "C" _LIBUNWIND_EXPORT __typeof(name) aliasname;
+#endif
+#else
+#error Unsupported target
+#endif
+
 #if (defined(__APPLE__) && defined(__arm__)) || defined(__USING_SJLJ_EXCEPTIONS__)
 #define _LIBUNWIND_BUILD_SJLJ_APIS
 #endif
diff --git a/src/dwarf2.h b/src/dwarf2.h
index 58525eea044e..40f0daf46805 100644
--- a/src/dwarf2.h
+++ b/src/dwarf2.h
@@ -1,9 +1,8 @@
 //===------------------------------- dwarf2.h -----------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //===----------------------------------------------------------------------===//
 
diff --git a/src/libunwind.cpp b/src/libunwind.cpp
index f4d71a1863bf..c90032bd66c9 100644
--- a/src/libunwind.cpp
+++ b/src/libunwind.cpp
@@ -1,9 +1,8 @@
 //===--------------------------- libunwind.cpp ----------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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 unw_* functions from <libunwind.h>
@@ -12,12 +11,6 @@
 
 #include <libunwind.h>
 
-#ifndef NDEBUG
-#include <cstdlib> // getenv
-#endif
-#include <new>
-#include <algorithm>
-
 #include "libunwind_ext.h"
 #include "config.h"
 
@@ -36,15 +29,11 @@ LocalAddressSpace LocalAddressSpace::sThisAddressSpace;
 _LIBUNWIND_EXPORT unw_addr_space_t unw_local_addr_space =
     (unw_addr_space_t)&LocalAddressSpace::sThisAddressSpace;
 
-/// record the registers and stack position of the caller
-extern int unw_getcontext(unw_context_t *);
-// note: unw_getcontext() implemented in assembly
-
 /// Create a cursor of a thread in this process given 'context' recorded by
-/// unw_getcontext().
-_LIBUNWIND_EXPORT int unw_init_local(unw_cursor_t *cursor,
-                                     unw_context_t *context) {
-  _LIBUNWIND_TRACE_API("unw_init_local(cursor=%p, context=%p)",
+/// __unw_getcontext().
+_LIBUNWIND_HIDDEN int __unw_init_local(unw_cursor_t *cursor,
+                                       unw_context_t *context) {
+  _LIBUNWIND_TRACE_API("__unw_init_local(cursor=%p, context=%p)",
                        static_cast<void *>(cursor),
                        static_cast<void *>(context));
 #if defined(__i386__)
@@ -73,101 +62,21 @@ _LIBUNWIND_EXPORT int unw_init_local(unw_cursor_t *cursor,
 # error Architecture not supported
 #endif
   // Use "placement new" to allocate UnwindCursor in the cursor buffer.
-  new ((void *)cursor) UnwindCursor<LocalAddressSpace, REGISTER_KIND>(
-                                 context, LocalAddressSpace::sThisAddressSpace);
+  new (reinterpret_cast<UnwindCursor<LocalAddressSpace, REGISTER_KIND> *>(cursor))
+      UnwindCursor<LocalAddressSpace, REGISTER_KIND>(
+          context, LocalAddressSpace::sThisAddressSpace);
 #undef REGISTER_KIND
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
   co->setInfoBasedOnIPRegister();
 
   return UNW_ESUCCESS;
 }
-
-#ifdef UNW_REMOTE
-/// Create a cursor into a thread in another process.
-_LIBUNWIND_EXPORT int unw_init_remote_thread(unw_cursor_t *cursor,
-                                             unw_addr_space_t as,
-                                             void *arg) {
-  // special case: unw_init_remote(xx, unw_local_addr_space, xx)
-  if (as == (unw_addr_space_t)&LocalAddressSpace::sThisAddressSpace)
-    return unw_init_local(cursor, NULL); //FIXME
-
-  // use "placement new" to allocate UnwindCursor in the cursor buffer
-  switch (as->cpuType) {
-  case CPU_TYPE_I386:
-    new ((void *)cursor)
-        UnwindCursor<RemoteAddressSpace<Pointer32<LittleEndian>>,
-                     Registers_x86>(((unw_addr_space_i386 *)as)->oas, arg);
-    break;
-  case CPU_TYPE_X86_64:
-    new ((void *)cursor)
-        UnwindCursor<RemoteAddressSpace<Pointer64<LittleEndian>>,
-                     Registers_x86_64>(((unw_addr_space_x86_64 *)as)->oas, arg);
-    break;
-  case CPU_TYPE_POWERPC:
-    new ((void *)cursor)
-        UnwindCursor<RemoteAddressSpace<Pointer32<BigEndian>>,
-                     Registers_ppc>(((unw_addr_space_ppc *)as)->oas, arg);
-    break;
-  default:
-    return UNW_EUNSPEC;
-  }
-  return UNW_ESUCCESS;
-}
-
-
-static bool is64bit(task_t task) {
-  return false; // FIXME
-}
-
-/// Create an address_space object for use in examining another task.
-_LIBUNWIND_EXPORT unw_addr_space_t unw_create_addr_space_for_task(task_t task) {
-#if __i386__
-  if (is64bit(task)) {
-    unw_addr_space_x86_64 *as = new unw_addr_space_x86_64(task);
-    as->taskPort = task;
-    as->cpuType = CPU_TYPE_X86_64;
-    //as->oas
-  } else {
-    unw_addr_space_i386 *as = new unw_addr_space_i386(task);
-    as->taskPort = task;
-    as->cpuType = CPU_TYPE_I386;
-    //as->oas
-  }
-#else
-// FIXME
-#endif
-}
-
-
-/// Delete an address_space object.
-_LIBUNWIND_EXPORT void unw_destroy_addr_space(unw_addr_space_t asp) {
-  switch (asp->cpuType) {
-#if __i386__ || __x86_64__
-  case CPU_TYPE_I386: {
-    unw_addr_space_i386 *as = (unw_addr_space_i386 *)asp;
-    delete as;
-  }
-  break;
-  case CPU_TYPE_X86_64: {
-    unw_addr_space_x86_64 *as = (unw_addr_space_x86_64 *)asp;
-    delete as;
-  }
-  break;
-#endif
-  case CPU_TYPE_POWERPC: {
-    unw_addr_space_ppc *as = (unw_addr_space_ppc *)asp;
-    delete as;
-  }
-  break;
-  }
-}
-#endif // UNW_REMOTE
-
+_LIBUNWIND_WEAK_ALIAS(__unw_init_local, unw_init_local)
 
 /// Get value of specified register at cursor position in stack frame.
-_LIBUNWIND_EXPORT int unw_get_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
-                                  unw_word_t *value) {
-  _LIBUNWIND_TRACE_API("unw_get_reg(cursor=%p, regNum=%d, &value=%p)",
+_LIBUNWIND_HIDDEN int __unw_get_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
+                                    unw_word_t *value) {
+  _LIBUNWIND_TRACE_API("__unw_get_reg(cursor=%p, regNum=%d, &value=%p)",
                        static_cast<void *>(cursor), regNum,
                        static_cast<void *>(value));
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
@@ -177,12 +86,13 @@ _LIBUNWIND_EXPORT int unw_get_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
   }
   return UNW_EBADREG;
 }
-
+_LIBUNWIND_WEAK_ALIAS(__unw_get_reg, unw_get_reg)
 
 /// Set value of specified register at cursor position in stack frame.
-_LIBUNWIND_EXPORT int unw_set_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
-                                  unw_word_t value) {
-  _LIBUNWIND_TRACE_API("unw_set_reg(cursor=%p, regNum=%d, value=0x%" PRIxPTR ")",
+_LIBUNWIND_HIDDEN int __unw_set_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
+                                    unw_word_t value) {
+  _LIBUNWIND_TRACE_API("__unw_set_reg(cursor=%p, regNum=%d, value=0x%" PRIxPTR
+                       ")",
                        static_cast<void *>(cursor), regNum, value);
   typedef LocalAddressSpace::pint_t pint_t;
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
@@ -208,12 +118,12 @@ _LIBUNWIND_EXPORT int unw_set_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
   }
   return UNW_EBADREG;
 }
-
+_LIBUNWIND_WEAK_ALIAS(__unw_set_reg, unw_set_reg)
 
 /// Get value of specified float register at cursor position in stack frame.
-_LIBUNWIND_EXPORT int unw_get_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum,
-                                    unw_fpreg_t *value) {
-  _LIBUNWIND_TRACE_API("unw_get_fpreg(cursor=%p, regNum=%d, &value=%p)",
+_LIBUNWIND_HIDDEN int __unw_get_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum,
+                                      unw_fpreg_t *value) {
+  _LIBUNWIND_TRACE_API("__unw_get_fpreg(cursor=%p, regNum=%d, &value=%p)",
                        static_cast<void *>(cursor), regNum,
                        static_cast<void *>(value));
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
@@ -223,16 +133,16 @@ _LIBUNWIND_EXPORT int unw_get_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum,
   }
   return UNW_EBADREG;
 }
-
+_LIBUNWIND_WEAK_ALIAS(__unw_get_fpreg, unw_get_fpreg)
 
 /// Set value of specified float register at cursor position in stack frame.
-_LIBUNWIND_EXPORT int unw_set_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum,
-                                    unw_fpreg_t value) {
+_LIBUNWIND_HIDDEN int __unw_set_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum,
+                                      unw_fpreg_t value) {
 #if defined(_LIBUNWIND_ARM_EHABI)
-  _LIBUNWIND_TRACE_API("unw_set_fpreg(cursor=%p, regNum=%d, value=%llX)",
+  _LIBUNWIND_TRACE_API("__unw_set_fpreg(cursor=%p, regNum=%d, value=%llX)",
                        static_cast<void *>(cursor), regNum, value);
 #else
-  _LIBUNWIND_TRACE_API("unw_set_fpreg(cursor=%p, regNum=%d, value=%g)",
+  _LIBUNWIND_TRACE_API("__unw_set_fpreg(cursor=%p, regNum=%d, value=%g)",
                        static_cast<void *>(cursor), regNum, value);
 #endif
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
@@ -242,20 +152,20 @@ _LIBUNWIND_EXPORT int unw_set_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum,
   }
   return UNW_EBADREG;
 }
-
+_LIBUNWIND_WEAK_ALIAS(__unw_set_fpreg, unw_set_fpreg)
 
 /// Move cursor to next frame.
-_LIBUNWIND_EXPORT int unw_step(unw_cursor_t *cursor) {
-  _LIBUNWIND_TRACE_API("unw_step(cursor=%p)", static_cast<void *>(cursor));
+_LIBUNWIND_HIDDEN int __unw_step(unw_cursor_t *cursor) {
+  _LIBUNWIND_TRACE_API("__unw_step(cursor=%p)", static_cast<void *>(cursor));
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
   return co->step();
 }
-
+_LIBUNWIND_WEAK_ALIAS(__unw_step, unw_step)
 
 /// Get unwind info at cursor position in stack frame.
-_LIBUNWIND_EXPORT int unw_get_proc_info(unw_cursor_t *cursor,
-                                        unw_proc_info_t *info) {
-  _LIBUNWIND_TRACE_API("unw_get_proc_info(cursor=%p, &info=%p)",
+_LIBUNWIND_HIDDEN int __unw_get_proc_info(unw_cursor_t *cursor,
+                                          unw_proc_info_t *info) {
+  _LIBUNWIND_TRACE_API("__unw_get_proc_info(cursor=%p, &info=%p)",
                        static_cast<void *>(cursor), static_cast<void *>(info));
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
   co->getInfo(info);
@@ -264,21 +174,21 @@ _LIBUNWIND_EXPORT int unw_get_proc_info(unw_cursor_t *cursor,
   else
     return UNW_ESUCCESS;
 }
-
+_LIBUNWIND_WEAK_ALIAS(__unw_get_proc_info, unw_get_proc_info)
 
 /// Resume execution at cursor position (aka longjump).
-_LIBUNWIND_EXPORT int unw_resume(unw_cursor_t *cursor) {
-  _LIBUNWIND_TRACE_API("unw_resume(cursor=%p)", static_cast<void *>(cursor));
+_LIBUNWIND_HIDDEN int __unw_resume(unw_cursor_t *cursor) {
+  _LIBUNWIND_TRACE_API("__unw_resume(cursor=%p)", static_cast<void *>(cursor));
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
   co->jumpto();
   return UNW_EUNSPEC;
 }
-
+_LIBUNWIND_WEAK_ALIAS(__unw_resume, unw_resume)
 
 /// Get name of function at cursor position in stack frame.
-_LIBUNWIND_EXPORT int unw_get_proc_name(unw_cursor_t *cursor, char *buf,
-                                        size_t bufLen, unw_word_t *offset) {
-  _LIBUNWIND_TRACE_API("unw_get_proc_name(cursor=%p, &buf=%p, bufLen=%lu)",
+_LIBUNWIND_HIDDEN int __unw_get_proc_name(unw_cursor_t *cursor, char *buf,
+                                          size_t bufLen, unw_word_t *offset) {
+  _LIBUNWIND_TRACE_API("__unw_get_proc_name(cursor=%p, &buf=%p, bufLen=%lu)",
                        static_cast<void *>(cursor), static_cast<void *>(buf),
                        static_cast<unsigned long>(bufLen));
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
@@ -287,58 +197,62 @@ _LIBUNWIND_EXPORT int unw_get_proc_name(unw_cursor_t *cursor, char *buf,
   else
     return UNW_EUNSPEC;
 }
-
+_LIBUNWIND_WEAK_ALIAS(__unw_get_proc_name, unw_get_proc_name)
 
 /// Checks if a register is a floating-point register.
-_LIBUNWIND_EXPORT int unw_is_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum) {
-  _LIBUNWIND_TRACE_API("unw_is_fpreg(cursor=%p, regNum=%d)",
+_LIBUNWIND_HIDDEN int __unw_is_fpreg(unw_cursor_t *cursor,
+                                     unw_regnum_t regNum) {
+  _LIBUNWIND_TRACE_API("__unw_is_fpreg(cursor=%p, regNum=%d)",
                        static_cast<void *>(cursor), regNum);
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
   return co->validFloatReg(regNum);
 }
-
+_LIBUNWIND_WEAK_ALIAS(__unw_is_fpreg, unw_is_fpreg)
 
 /// Checks if a register is a floating-point register.
-_LIBUNWIND_EXPORT const char *unw_regname(unw_cursor_t *cursor,
-                                          unw_regnum_t regNum) {
-  _LIBUNWIND_TRACE_API("unw_regname(cursor=%p, regNum=%d)",
+_LIBUNWIND_HIDDEN const char *__unw_regname(unw_cursor_t *cursor,
+                                            unw_regnum_t regNum) {
+  _LIBUNWIND_TRACE_API("__unw_regname(cursor=%p, regNum=%d)",
                        static_cast<void *>(cursor), regNum);
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
   return co->getRegisterName(regNum);
 }
-
+_LIBUNWIND_WEAK_ALIAS(__unw_regname, unw_regname)
 
 /// Checks if current frame is signal trampoline.
-_LIBUNWIND_EXPORT int unw_is_signal_frame(unw_cursor_t *cursor) {
-  _LIBUNWIND_TRACE_API("unw_is_signal_frame(cursor=%p)",
+_LIBUNWIND_HIDDEN int __unw_is_signal_frame(unw_cursor_t *cursor) {
+  _LIBUNWIND_TRACE_API("__unw_is_signal_frame(cursor=%p)",
                        static_cast<void *>(cursor));
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
   return co->isSignalFrame();
 }
+_LIBUNWIND_WEAK_ALIAS(__unw_is_signal_frame, unw_is_signal_frame)
 
 #ifdef __arm__
 // Save VFP registers d0-d15 using FSTMIADX instead of FSTMIADD
-_LIBUNWIND_EXPORT void unw_save_vfp_as_X(unw_cursor_t *cursor) {
-  _LIBUNWIND_TRACE_API("unw_fpreg_save_vfp_as_X(cursor=%p)",
+_LIBUNWIND_HIDDEN void __unw_save_vfp_as_X(unw_cursor_t *cursor) {
+  _LIBUNWIND_TRACE_API("__unw_get_fpreg_save_vfp_as_X(cursor=%p)",
                        static_cast<void *>(cursor));
   AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
   return co->saveVFPAsX();
 }
+_LIBUNWIND_WEAK_ALIAS(__unw_save_vfp_as_X, unw_save_vfp_as_X)
 #endif
 
 
 #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
 /// SPI: walks cached DWARF entries
-_LIBUNWIND_EXPORT void unw_iterate_dwarf_unwind_cache(void (*func)(
+_LIBUNWIND_HIDDEN void __unw_iterate_dwarf_unwind_cache(void (*func)(
     unw_word_t ip_start, unw_word_t ip_end, unw_word_t fde, unw_word_t mh)) {
-  _LIBUNWIND_TRACE_API("unw_iterate_dwarf_unwind_cache(func=%p)",
+  _LIBUNWIND_TRACE_API("__unw_iterate_dwarf_unwind_cache(func=%p)",
                        reinterpret_cast<void *>(func));
   DwarfFDECache<LocalAddressSpace>::iterateCacheEntries(func);
 }
-
+_LIBUNWIND_WEAK_ALIAS(__unw_iterate_dwarf_unwind_cache,
+                      unw_iterate_dwarf_unwind_cache)
 
 /// IPI: for __register_frame()
-void _unw_add_dynamic_fde(unw_word_t fde) {
+void __unw_add_dynamic_fde(unw_word_t fde) {
   CFI_Parser<LocalAddressSpace>::FDE_Info fdeInfo;
   CFI_Parser<LocalAddressSpace>::CIE_Info cieInfo;
   const char *message = CFI_Parser<LocalAddressSpace>::decodeFDE(
@@ -352,12 +266,12 @@ void _unw_add_dynamic_fde(unw_word_t fde) {
                                           fdeInfo.pcStart, fdeInfo.pcEnd,
                                           fdeInfo.fdeStart);
   } else {
-    _LIBUNWIND_DEBUG_LOG("_unw_add_dynamic_fde: bad fde: %s", message);
+    _LIBUNWIND_DEBUG_LOG("__unw_add_dynamic_fde: bad fde: %s", message);
   }
 }
 
 /// IPI: for __deregister_frame()
-void _unw_remove_dynamic_fde(unw_word_t fde) {
+void __unw_remove_dynamic_fde(unw_word_t fde) {
   // fde is own mh_group
   DwarfFDECache<LocalAddressSpace>::removeAllIn((LocalAddressSpace::pint_t)fde);
 }
diff --git a/src/libunwind_ext.h b/src/libunwind_ext.h
index ec645a846739..316dee298246 100644
--- a/src/libunwind_ext.h
+++ b/src/libunwind_ext.h
@@ -1,9 +1,8 @@
 //===------------------------ libunwind_ext.h -----------------------------===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
+// 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
 //
 //
 //  Extensions to libunwind API.
@@ -23,15 +22,34 @@
 #ifdef __cplusplus
 extern "C" {
 #endif
+
+extern int __unw_getcontext(unw_context_t *);
+extern int __unw_init_local(unw_cursor_t *, unw_context_t *);
+extern int __unw_step(unw_cursor_t *);
+extern int __unw_get_reg(unw_cursor_t *, unw_regnum_t, unw_word_t *);
+extern int __unw_get_fpreg(unw_cursor_t *, unw_regnum_t, unw_fpreg_t *);
+extern int __unw_set_reg(unw_cursor_t *, unw_regnum_t, unw_word_t);
+extern int __unw_set_fpreg(unw_cursor_t *, unw_regnum_t, unw_fpreg_t);
+extern int __unw_resume(unw_cursor_t *);
+
+#ifdef __arm__
+/* Save VFP registers in FSTMX format (instead of FSTMD). */
+extern void __unw_save_vfp_as_X(unw_cursor_t *);
+#endif
+
+extern const char *__unw_regname(unw_cursor_t *, unw_regnum_t);
+extern int __unw_get_proc_info(unw_cursor_t *, unw_proc_info_t *);
+extern int __unw_is_fpreg(unw_cursor_t *, unw_regnum_t);
+extern int __unw_is_signal_frame(unw_cursor_t *);
+extern int __unw_get_proc_name(unw_cursor_t *, char *, size_t, unw_word_t *);
+
 // SPI
-extern void unw_iterate_dwarf_unwind_cache(void (*func)(unw_word_t ip_start,
-                                                        unw_word_t ip_end,
-                                                        unw_word_t fde,
-                                                        unw_word_t mh));
+extern void __unw_iterate_dwarf_unwind_cache(void (*func)(
+    unw_word_t ip_start, unw_word_t ip_end, unw_word_t fde, unw_word_t mh));
 
 // IPI
-extern void _unw_add_dynamic_fde(unw_word_t fde);
-extern void _unw_remove_dynamic_fde(unw_word_t fde);
+extern void __unw_add_dynamic_fde(unw_word_t fde);
+extern void __unw_remove_dynamic_fde(unw_word_t fde);
 
 #if defined(_LIBUNWIND_ARM_EHABI)
 extern const uint32_t* decode_eht_entry(const uint32_t*, size_t*, size_t*);