Vendor import of llvm release_30 branch r142614:

http://llvm.org/svn/llvm-project/llvm/branches/release_30@142614

7 files changed, 428 insertions, 89 deletions

diff --git a/lib/Support/Windows/DynamicLibrary.inc b/lib/Support/Windows/DynamicLibrary.inc
index fc5f580..83da82a 100644
--- a/lib/Support/Windows/DynamicLibrary.inc
+++ b/lib/Support/Windows/DynamicLibrary.inc
@@ -39,7 +39,7 @@ using namespace sys;
 //===          and must not be UNIX code.
 //===----------------------------------------------------------------------===//
 
-static std::vector<HMODULE> OpenedHandles;
+static DenseSet<HMODULE> *OpenedHandles;
 
 extern "C" {
 
@@ -63,30 +63,43 @@ extern "C" {
 #endif
         stricmp(ModuleName, "msvcrt20") != 0 &&
         stricmp(ModuleName, "msvcrt40") != 0) {
-      OpenedHandles.push_back((HMODULE)ModuleBase);
+      OpenedHandles->insert((HMODULE)ModuleBase);
     }
     return TRUE;
   }
 }
 
-bool DynamicLibrary::LoadLibraryPermanently(const char *filename,
-                                            std::string *ErrMsg) {
-  if (filename) {
-    HMODULE a_handle = LoadLibrary(filename);
+DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename,
+                                                   std::string *errMsg) {
+  SmartScopedLock<true> lock(getMutex());
 
-    if (a_handle == 0)
-      return MakeErrMsg(ErrMsg, std::string(filename) + ": Can't open : ");
+  if (!filename) {
+    // When no file is specified, enumerate all DLLs and EXEs in the process.
+    if (OpenedHandles == 0)
+      OpenedHandles = new DenseSet<HMODULE>();
 
-    OpenedHandles.push_back(a_handle);
-  } else {
-    // When no file is specified, enumerate all DLLs and EXEs in the
-    // process.
     EnumerateLoadedModules(GetCurrentProcess(), ELM_Callback, 0);
+    // Dummy library that represents "search all handles".
+    // This is mostly to ensure that the return value still shows up as "valid".
+    return DynamicLibrary(&OpenedHandles);
   }
+  
+  HMODULE a_handle = LoadLibrary(filename);
 
-  // Because we don't remember the handle, we will never free it; hence,
-  // it is loaded permanently.
-  return false;
+  if (a_handle == 0) {
+    MakeErrMsg(errMsg, std::string(filename) + ": Can't open : ");
+    return DynamicLibrary();
+  }
+
+  if (OpenedHandles == 0)
+    OpenedHandles = new DenseSet<HMODULE>();
+
+  // If we've already loaded this library, FreeLibrary() the handle in order to
+  // keep the internal refcount at +1.
+  if (!OpenedHandles->insert(a_handle).second)
+    FreeLibrary(a_handle);
+
+  return DynamicLibrary(a_handle);
 }
 
 // Stack probing routines are in the support library (e.g. libgcc), but we don't
@@ -101,21 +114,24 @@ bool DynamicLibrary::LoadLibraryPermanently(const char *filename,
 #undef EXPLICIT_SYMBOL2
 
 void* DynamicLibrary::SearchForAddressOfSymbol(const char* symbolName) {
+  SmartScopedLock<true> Lock(getMutex());
+
   // First check symbols added via AddSymbol().
   if (ExplicitSymbols) {
-    std::map<std::string, void *>::iterator I =
-      ExplicitSymbols->find(symbolName);
-    std::map<std::string, void *>::iterator E = ExplicitSymbols->end();
-    if (I != E)
-      return I->second;
+    StringMap<void *>::iterator i = ExplicitSymbols->find(symbolName);
+
+    if (i != ExplicitSymbols->end())
+      return i->second;
   }
 
   // Now search the libraries.
-  for (std::vector<HMODULE>::iterator I = OpenedHandles.begin(),
-       E = OpenedHandles.end(); I != E; ++I) {
-    FARPROC ptr = GetProcAddress((HMODULE)*I, symbolName);
-    if (ptr) {
-      return (void *)(intptr_t)ptr;
+  if (OpenedHandles) {
+    for (DenseSet<HMODULE>::iterator I = OpenedHandles->begin(),
+         E = OpenedHandles->end(); I != E; ++I) {
+      FARPROC ptr = GetProcAddress((HMODULE)*I, symbolName);
+      if (ptr) {
+        return (void *)(intptr_t)ptr;
+      }
     }
   }
 
@@ -134,4 +150,14 @@ void* DynamicLibrary::SearchForAddressOfSymbol(const char* symbolName) {
   return 0;
 }
 
+
+void *DynamicLibrary::getAddressOfSymbol(const char *symbolName) {
+  if (!isValid())
+    return NULL;
+  if (Data == &OpenedHandles)
+    return SearchForAddressOfSymbol(symbolName);
+  return (void *)(intptr_t)GetProcAddress((HMODULE)Data, symbolName);
+}
+
+
 }
diff --git a/lib/Support/Windows/Memory.inc b/lib/Support/Windows/Memory.inc
index 9f69e73..fcc7283 100644
--- a/lib/Support/Windows/Memory.inc
+++ b/lib/Support/Windows/Memory.inc
@@ -32,11 +32,16 @@ MemoryBlock Memory::AllocateRWX(size_t NumBytes,
   static const size_t pageSize = Process::GetPageSize();
   size_t NumPages = (NumBytes+pageSize-1)/pageSize;
 
-  //FIXME: support NearBlock if ever needed on Win64.
+  PVOID start = NearBlock ? static_cast<unsigned char *>(NearBlock->base()) +
+                                NearBlock->size() : NULL;
 
-  void *pa = VirtualAlloc(NULL, NumPages*pageSize, MEM_COMMIT,
+  void *pa = VirtualAlloc(start, NumPages*pageSize, MEM_RESERVE | MEM_COMMIT,
                   PAGE_EXECUTE_READWRITE);
   if (pa == NULL) {
+    if (NearBlock) {
+      // Try again without the NearBlock hint
+      return AllocateRWX(NumBytes, NULL, ErrMsg);
+    }
     MakeErrMsg(ErrMsg, "Can't allocate RWX Memory: ");
     return MemoryBlock();
   }
@@ -54,20 +59,62 @@ bool Memory::ReleaseRWX(MemoryBlock &M, std::string *ErrMsg) {
   return false;
 }
 
+static DWORD getProtection(const void *addr) {
+  MEMORY_BASIC_INFORMATION info;
+  if (sizeof(info) == ::VirtualQuery(addr, &info, sizeof(info))) {
+    return info.Protect;
+  }
+  return 0;
+}
+
 bool Memory::setWritable(MemoryBlock &M, std::string *ErrMsg) {
+  if (!setRangeWritable(M.Address, M.Size)) {
+    return MakeErrMsg(ErrMsg, "Cannot set memory to writeable: ");
+  }
   return true;
 }
 
 bool Memory::setExecutable(MemoryBlock &M, std::string *ErrMsg) {
-  return false;
+  if (!setRangeExecutable(M.Address, M.Size)) {
+    return MakeErrMsg(ErrMsg, "Cannot set memory to executable: ");
+  }
+  return true;
 }
 
 bool Memory::setRangeWritable(const void *Addr, size_t Size) {
-  return true;
+  DWORD prot = getProtection(Addr);
+  if (!prot)
+    return false;
+
+  if (prot == PAGE_EXECUTE || prot == PAGE_EXECUTE_READ) {
+    prot = PAGE_EXECUTE_READWRITE;
+  } else if (prot == PAGE_NOACCESS || prot == PAGE_READONLY) {
+    prot = PAGE_READWRITE;
+  }
+
+  DWORD oldProt;
+  sys::Memory::InvalidateInstructionCache(Addr, Size);
+  return ::VirtualProtect(const_cast<LPVOID>(Addr), Size, prot, &oldProt)
+            == TRUE;
 }
 
 bool Memory::setRangeExecutable(const void *Addr, size_t Size) {
-  return false;
+  DWORD prot = getProtection(Addr);
+  if (!prot)
+    return false;
+
+  if (prot == PAGE_NOACCESS) {
+    prot = PAGE_EXECUTE;
+  } else if (prot == PAGE_READONLY) {
+    prot = PAGE_EXECUTE_READ;
+  } else if (prot == PAGE_READWRITE) {
+    prot = PAGE_EXECUTE_READWRITE;
+  }
+
+  DWORD oldProt;
+  sys::Memory::InvalidateInstructionCache(Addr, Size);
+  return ::VirtualProtect(const_cast<LPVOID>(Addr), Size, prot, &oldProt)
+            == TRUE;
 }
 
 }
diff --git a/lib/Support/Windows/PathV2.inc b/lib/Support/Windows/PathV2.inc
index af71b73..bc597b2 100644
--- a/lib/Support/Windows/PathV2.inc
+++ b/lib/Support/Windows/PathV2.inc
@@ -445,13 +445,35 @@ error_code file_size(const Twine &path, uint64_t &result) {
   return success;
 }
 
+static bool isReservedName(StringRef path) {
+  // This list of reserved names comes from MSDN, at:
+  // http://msdn.microsoft.com/en-us/library/aa365247%28v=vs.85%29.aspx
+  static const char *sReservedNames[] = { "nul", "con", "prn", "aux",
+                              "com1", "com2", "com3", "com4", "com5", "com6",
+                              "com7", "com8", "com9", "lpt1", "lpt2", "lpt3",
+                              "lpt4", "lpt5", "lpt6", "lpt7", "lpt8", "lpt9" };
+
+  // First, check to see if this is a device namespace, which always
+  // starts with \\.\, since device namespaces are not legal file paths.
+  if (path.startswith("\\\\.\\"))
+    return true;
+
+  // Then compare against the list of ancient reserved names
+  for (size_t i = 0; i < sizeof(sReservedNames) / sizeof(const char *); ++i) {
+    if (path.equals_lower(sReservedNames[i]))
+      return true;
+  }
+
+  // The path isn't what we consider reserved.
+  return false;
+}
+
 error_code status(const Twine &path, file_status &result) {
   SmallString<128> path_storage;
   SmallVector<wchar_t, 128> path_utf16;
 
   StringRef path8 = path.toStringRef(path_storage);
-  // FIXME: We should detect as many "special file name" as possible.
-  if (path8.compare_lower("nul") == 0) {
+  if (isReservedName(path8)) {
     result = file_status(file_type::character_file);
     return success;
   }
@@ -501,7 +523,8 @@ handle_status_error:
 }
 
 error_code unique_file(const Twine &model, int &result_fd,
-                             SmallVectorImpl<char> &result_path) {
+                             SmallVectorImpl<char> &result_path,
+                             bool makeAbsolute) {
   // Use result_path as temp storage.
   result_path.set_size(0);
   StringRef m = model.toStringRef(result_path);
@@ -509,17 +532,19 @@ error_code unique_file(const Twine &model, int &result_fd,
   SmallVector<wchar_t, 128> model_utf16;
   if (error_code ec = UTF8ToUTF16(m, model_utf16)) return ec;
 
-  // Make model absolute by prepending a temp directory if it's not already.
-  bool absolute = path::is_absolute(m);
-
-  if (!absolute) {
-    SmallVector<wchar_t, 64> temp_dir;
-    if (error_code ec = TempDir(temp_dir)) return ec;
-    // Handle c: by removing it.
-    if (model_utf16.size() > 2 && model_utf16[1] == L':') {
-      model_utf16.erase(model_utf16.begin(), model_utf16.begin() + 2);
+  if (makeAbsolute) {
+    // Make model absolute by prepending a temp directory if it's not already.
+    bool absolute = path::is_absolute(m);
+  
+    if (!absolute) {
+      SmallVector<wchar_t, 64> temp_dir;
+      if (error_code ec = TempDir(temp_dir)) return ec;
+      // Handle c: by removing it.
+      if (model_utf16.size() > 2 && model_utf16[1] == L':') {
+        model_utf16.erase(model_utf16.begin(), model_utf16.begin() + 2);
+      }
+      model_utf16.insert(model_utf16.begin(), temp_dir.begin(), temp_dir.end());
     }
-    model_utf16.insert(model_utf16.begin(), temp_dir.begin(), temp_dir.end());
   }
 
   // Replace '%' with random chars. From here on, DO NOT modify model. It may be
diff --git a/lib/Support/Windows/Process.inc b/lib/Support/Windows/Process.inc
index 06a7f00..fe54eb1 100644
--- a/lib/Support/Windows/Process.inc
+++ b/lib/Support/Windows/Process.inc
@@ -15,6 +15,7 @@
 #include <psapi.h>
 #include <malloc.h>
 #include <io.h>
+#include <direct.h>
 
 #ifdef __MINGW32__
  #if (HAVE_LIBPSAPI != 1)
@@ -219,4 +220,8 @@ const char *Process::ResetColor() {
   return 0;
 }
 
+void Process::SetWorkingDirectory(std::string Path) {
+  ::_chdir(Path.c_str());
+}
+
 }
diff --git a/lib/Support/Windows/RWMutex.inc b/lib/Support/Windows/RWMutex.inc
index 471f8fa..26b9bba 100644
--- a/lib/Support/Windows/RWMutex.inc
+++ b/lib/Support/Windows/RWMutex.inc
@@ -18,39 +18,115 @@
 
 #include "Windows.h"
 
-// FIXME: Windows does not have reader-writer locks pre-Vista.  If you want
-// real reader-writer locks, you a threads implementation for Windows.
-
 namespace llvm {
 using namespace sys;
 
+// Windows has slim read-writer lock support on Vista and higher, so we
+// will attempt to load the APIs.  If they exist, we will use them, and
+// if not, we will fall back on critical sections.  When we drop support
+// for XP, we can stop lazy-loading these APIs and just use them directly.
+#if defined(__MINGW32__)
+  // Taken from WinNT.h
+  typedef struct _RTL_SRWLOCK {
+    PVOID Ptr;
+  } RTL_SRWLOCK, *PRTL_SRWLOCK;
+
+  // Taken from WinBase.h
+  typedef RTL_SRWLOCK SRWLOCK, *PSRWLOCK;
+#endif
+
+static VOID (WINAPI *fpInitializeSRWLock)(PSRWLOCK lock) = NULL;
+static VOID (WINAPI *fpAcquireSRWLockExclusive)(PSRWLOCK lock) = NULL;
+static VOID (WINAPI *fpAcquireSRWLockShared)(PSRWLOCK lock) = NULL;
+static VOID (WINAPI *fpReleaseSRWLockExclusive)(PSRWLOCK lock) = NULL;
+static VOID (WINAPI *fpReleaseSRWLockShared)(PSRWLOCK lock) = NULL;
+
+static bool sHasSRW = false;
+
+static bool loadSRW() {
+  static bool sChecked = false;
+  if (!sChecked) {
+    sChecked = true;
+
+    HMODULE hLib = ::LoadLibrary(TEXT("Kernel32"));
+    if (hLib) {
+      fpInitializeSRWLock =
+        (VOID (WINAPI *)(PSRWLOCK))::GetProcAddress(hLib,
+                                               "InitializeSRWLock");
+      fpAcquireSRWLockExclusive =
+        (VOID (WINAPI *)(PSRWLOCK))::GetProcAddress(hLib,
+                                               "AcquireSRWLockExclusive");
+      fpAcquireSRWLockShared =
+        (VOID (WINAPI *)(PSRWLOCK))::GetProcAddress(hLib,
+                                               "AcquireSRWLockShared");
+      fpReleaseSRWLockExclusive =
+        (VOID (WINAPI *)(PSRWLOCK))::GetProcAddress(hLib,
+                                               "ReleaseSRWLockExclusive");
+      fpReleaseSRWLockShared =
+        (VOID (WINAPI *)(PSRWLOCK))::GetProcAddress(hLib,
+                                               "ReleaseSRWLockShared");
+      ::FreeLibrary(hLib);
+
+	  if (fpInitializeSRWLock != NULL) {
+	    sHasSRW = true;
+	  }
+    }
+  }
+  return sHasSRW;
+}
+
 RWMutexImpl::RWMutexImpl() {
-  data_ = calloc(1, sizeof(CRITICAL_SECTION));
-  InitializeCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
+  if (loadSRW()) {
+    data_ = calloc(1, sizeof(SRWLOCK));
+    fpInitializeSRWLock(static_cast<PSRWLOCK>(data_));
+  } else {
+    data_ = calloc(1, sizeof(CRITICAL_SECTION));
+    InitializeCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
+  }
 }
 
 RWMutexImpl::~RWMutexImpl() {
-  DeleteCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
-  free(data_);
+  if (sHasSRW) {
+    // Nothing to do in the case of slim reader/writers
+  } else {
+    DeleteCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
+    free(data_);
+  }
 }
 
 bool RWMutexImpl::reader_acquire() {
-  EnterCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
+  if (sHasSRW) {
+    fpAcquireSRWLockShared(static_cast<PSRWLOCK>(data_));
+  } else {
+    EnterCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
+  }
   return true;
 }
 
 bool RWMutexImpl::reader_release() {
-  LeaveCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
+  if (sHasSRW) {
+    fpReleaseSRWLockShared(static_cast<PSRWLOCK>(data_));
+  } else {
+    LeaveCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
+  }
   return true;
 }
 
 bool RWMutexImpl::writer_acquire() {
-  EnterCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
+  if (sHasSRW) {
+    fpAcquireSRWLockExclusive(static_cast<PSRWLOCK>(data_));
+  } else {
+    EnterCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
+  }
   return true;
 }
 
 bool RWMutexImpl::writer_release() {
-  LeaveCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
+  if (sHasSRW) {
+    fpReleaseSRWLockExclusive(static_cast<PSRWLOCK>(data_));
+  } else {
+    LeaveCriticalSection(static_cast<LPCRITICAL_SECTION>(data_));
+  }
   return true;
 }
 
diff --git a/lib/Support/Windows/Signals.inc b/lib/Support/Windows/Signals.inc
index 14f3f21..0d4b8a2 100644
--- a/lib/Support/Windows/Signals.inc
+++ b/lib/Support/Windows/Signals.inc
@@ -23,14 +23,133 @@
 #endif
 #include <psapi.h>
 
-#ifdef __MINGW32__
+#ifdef _MSC_VER
+ #pragma comment(lib, "psapi.lib")
+ #pragma comment(lib, "dbghelp.lib")
+#elif __MINGW32__
  #if ((HAVE_LIBIMAGEHLP != 1) || (HAVE_LIBPSAPI != 1))
   #error "libimagehlp.a & libpsapi.a should be present"
  #endif
-#else
- #pragma comment(lib, "psapi.lib")
- #pragma comment(lib, "dbghelp.lib")
-#endif
+ // The version of g++ that comes with MinGW does *not* properly understand
+ // the ll format specifier for printf. However, MinGW passes the format
+ // specifiers on to the MSVCRT entirely, and the CRT understands the ll
+ // specifier. So these warnings are spurious in this case. Since we compile
+ // with -Wall, this will generate these warnings which should be ignored. So
+ // we will turn off the warnings for this just file. However, MinGW also does
+ // not support push and pop for diagnostics, so we have to manually turn it
+ // back on at the end of the file.
+ #pragma GCC diagnostic ignored "-Wformat"
+ #pragma GCC diagnostic ignored "-Wformat-extra-args"
+
+ #if !defined(__MINGW64_VERSION_MAJOR)
+ // MinGW.org does not have updated support for the 64-bit versions of the
+ // DebugHlp APIs. So we will have to load them manually. The structures and
+ // method signatures were pulled from DbgHelp.h in the Windows Platform SDK,
+ // and adjusted for brevity.
+ typedef struct _IMAGEHLP_LINE64 {
+   DWORD    SizeOfStruct;
+   PVOID    Key;
+   DWORD    LineNumber;
+   PCHAR    FileName;
+   DWORD64  Address;
+ } IMAGEHLP_LINE64, *PIMAGEHLP_LINE64;
+
+ typedef struct _IMAGEHLP_SYMBOL64 {
+   DWORD   SizeOfStruct;
+   DWORD64 Address;
+   DWORD   Size;
+   DWORD   Flags;
+   DWORD   MaxNameLength;
+   CHAR    Name[1];
+ } IMAGEHLP_SYMBOL64, *PIMAGEHLP_SYMBOL64;
+
+ typedef struct _tagADDRESS64 {
+   DWORD64       Offset;
+   WORD          Segment;
+   ADDRESS_MODE  Mode;
+ } ADDRESS64, *LPADDRESS64;
+
+ typedef struct _KDHELP64 {
+   DWORD64   Thread;
+   DWORD   ThCallbackStack;
+   DWORD   ThCallbackBStore;
+   DWORD   NextCallback;
+   DWORD   FramePointer;
+   DWORD64   KiCallUserMode;
+   DWORD64   KeUserCallbackDispatcher;
+   DWORD64   SystemRangeStart;
+   DWORD64   KiUserExceptionDispatcher;
+   DWORD64   StackBase;
+   DWORD64   StackLimit;
+   DWORD64   Reserved[5];
+ } KDHELP64, *PKDHELP64;
+
+ typedef struct _tagSTACKFRAME64 {
+   ADDRESS64   AddrPC;
+   ADDRESS64   AddrReturn;
+   ADDRESS64   AddrFrame;
+   ADDRESS64   AddrStack;
+   ADDRESS64   AddrBStore;
+   PVOID       FuncTableEntry;
+   DWORD64     Params[4];
+   BOOL        Far;
+   BOOL        Virtual;
+   DWORD64     Reserved[3];
+   KDHELP64    KdHelp;
+ } STACKFRAME64, *LPSTACKFRAME64;
+
+typedef BOOL (__stdcall *PREAD_PROCESS_MEMORY_ROUTINE64)(HANDLE hProcess,
+                      DWORD64 qwBaseAddress, PVOID lpBuffer, DWORD nSize,
+                      LPDWORD lpNumberOfBytesRead);
+
+typedef PVOID (__stdcall *PFUNCTION_TABLE_ACCESS_ROUTINE64)( HANDLE ahProcess,
+                      DWORD64 AddrBase);
+
+typedef DWORD64 (__stdcall *PGET_MODULE_BASE_ROUTINE64)(HANDLE hProcess,
+                      DWORD64 Address);
+
+typedef DWORD64 (__stdcall *PTRANSLATE_ADDRESS_ROUTINE64)(HANDLE hProcess,
+                      HANDLE hThread, LPADDRESS64 lpaddr);
+
+typedef BOOL (WINAPI *fpStackWalk64)(DWORD, HANDLE, HANDLE, LPSTACKFRAME64,
+                      PVOID, PREAD_PROCESS_MEMORY_ROUTINE64,
+                      PFUNCTION_TABLE_ACCESS_ROUTINE64,
+                      PGET_MODULE_BASE_ROUTINE64,
+                      PTRANSLATE_ADDRESS_ROUTINE64);
+static fpStackWalk64 StackWalk64;
+
+typedef DWORD64 (WINAPI *fpSymGetModuleBase64)(HANDLE, DWORD64);
+static fpSymGetModuleBase64 SymGetModuleBase64;
+
+typedef BOOL (WINAPI *fpSymGetSymFromAddr64)(HANDLE, DWORD64,
+                      PDWORD64, PIMAGEHLP_SYMBOL64);
+static fpSymGetSymFromAddr64 SymGetSymFromAddr64;
+
+typedef BOOL (WINAPI *fpSymGetLineFromAddr64)(HANDLE, DWORD64,
+                      PDWORD, PIMAGEHLP_LINE64);
+static fpSymGetLineFromAddr64 SymGetLineFromAddr64;
+
+typedef PVOID (WINAPI *fpSymFunctionTableAccess64)(HANDLE, DWORD64);
+static fpSymFunctionTableAccess64 SymFunctionTableAccess64;
+
+static bool load64BitDebugHelp(void) {
+  HMODULE hLib = ::LoadLibrary("Dbghelp.dll");
+  if (hLib) {
+    StackWalk64 = (fpStackWalk64)
+                      ::GetProcAddress(hLib, "StackWalk64");
+    SymGetModuleBase64 = (fpSymGetModuleBase64)
+                      ::GetProcAddress(hLib, "SymGetModuleBase64");
+    SymGetSymFromAddr64 = (fpSymGetSymFromAddr64)
+                      ::GetProcAddress(hLib, "SymGetSymFromAddr64");
+    SymGetLineFromAddr64 = (fpSymGetLineFromAddr64)
+                      ::GetProcAddress(hLib, "SymGetLineFromAddr64");
+    SymFunctionTableAccess64 = (fpSymFunctionTableAccess64)
+                     ::GetProcAddress(hLib, "SymFunctionTableAccess64");
+  }
+  return StackWalk64 != NULL;
+}
+ #endif // !defined(__MINGW64_VERSION_MAJOR)
+#endif // __MINGW32__
 
 // Forward declare.
 static LONG WINAPI LLVMUnhandledExceptionFilter(LPEXCEPTION_POINTERS ep);
@@ -90,6 +209,18 @@ static int CRTReportHook(int ReportType, char *Message, int *Return) {
 #endif
 
 static void RegisterHandler() {
+#if __MINGW32__ && !defined(__MINGW64_VERSION_MAJOR)
+  // On MinGW.org, we need to load up the symbols explicitly, because the
+  // Win32 framework they include does not have support for the 64-bit
+  // versions of the APIs we need.  If we cannot load up the APIs (which
+  // would be unexpected as they should exist on every version of Windows
+  // we support), we will bail out since there would be nothing to report.
+  if (!load64BitDebugHelp()) {
+    assert(false && "These APIs should always be available");
+    return;
+  }
+#endif
+
   if (RegisteredUnhandledExceptionFilter) {
     EnterCriticalSection(&CriticalSection);
     return;
@@ -213,20 +344,28 @@ void llvm::sys::RunInterruptHandlers() {
 static LONG WINAPI LLVMUnhandledExceptionFilter(LPEXCEPTION_POINTERS ep) {
   Cleanup();
 
-#ifdef _WIN64
-  // TODO: provide a x64 friendly version of the following
-#else
-
   // Initialize the STACKFRAME structure.
-  STACKFRAME StackFrame;
+  STACKFRAME64 StackFrame;
   memset(&StackFrame, 0, sizeof(StackFrame));
 
+  DWORD machineType;
+#if defined(_M_X64)
+  machineType = IMAGE_FILE_MACHINE_AMD64;
+  StackFrame.AddrPC.Offset = ep->ContextRecord->Rip;
+  StackFrame.AddrPC.Mode = AddrModeFlat;
+  StackFrame.AddrStack.Offset = ep->ContextRecord->Rsp;
+  StackFrame.AddrStack.Mode = AddrModeFlat;
+  StackFrame.AddrFrame.Offset = ep->ContextRecord->Rbp;
+  StackFrame.AddrFrame.Mode = AddrModeFlat;
+#elif defined(_M_IX86)
+  machineType = IMAGE_FILE_MACHINE_I386;
   StackFrame.AddrPC.Offset = ep->ContextRecord->Eip;
   StackFrame.AddrPC.Mode = AddrModeFlat;
   StackFrame.AddrStack.Offset = ep->ContextRecord->Esp;
   StackFrame.AddrStack.Mode = AddrModeFlat;
   StackFrame.AddrFrame.Offset = ep->ContextRecord->Ebp;
   StackFrame.AddrFrame.Mode = AddrModeFlat;
+#endif
 
   HANDLE hProcess = GetCurrentProcess();
   HANDLE hThread = GetCurrentThread();
@@ -236,9 +375,9 @@ static LONG WINAPI LLVMUnhandledExceptionFilter(LPEXCEPTION_POINTERS ep) {
   SymInitialize(hProcess, NULL, TRUE);
 
   while (true) {
-    if (!StackWalk(IMAGE_FILE_MACHINE_I386, hProcess, hThread, &StackFrame,
-                   ep->ContextRecord, NULL, SymFunctionTableAccess,
-                   SymGetModuleBase, NULL)) {
+    if (!StackWalk64(machineType, hProcess, hThread, &StackFrame,
+                   ep->ContextRecord, NULL, SymFunctionTableAccess64,
+                   SymGetModuleBase64, NULL)) {
       break;
     }
 
@@ -246,54 +385,66 @@ static LONG WINAPI LLVMUnhandledExceptionFilter(LPEXCEPTION_POINTERS ep) {
       break;
 
     // Print the PC in hexadecimal.
-    DWORD PC = StackFrame.AddrPC.Offset;
-    fprintf(stderr, "%08lX", PC);
+    DWORD64 PC = StackFrame.AddrPC.Offset;
+#if defined(_M_X64)
+    fprintf(stderr, "0x%016llX", PC);
+#elif defined(_M_IX86)
+    fprintf(stderr, "0x%08lX", static_cast<DWORD>(PC));
+#endif
 
     // Print the parameters.  Assume there are four.
+#if defined(_M_X64)
+    fprintf(stderr, " (0x%016llX 0x%016llX 0x%016llX 0x%016llX)",
+                StackFrame.Params[0],
+                StackFrame.Params[1],
+                StackFrame.Params[2],
+                StackFrame.Params[3]);
+#elif defined(_M_IX86)
     fprintf(stderr, " (0x%08lX 0x%08lX 0x%08lX 0x%08lX)",
-            StackFrame.Params[0],
-            StackFrame.Params[1], StackFrame.Params[2], StackFrame.Params[3]);
-
+                static_cast<DWORD>(StackFrame.Params[0]),
+                static_cast<DWORD>(StackFrame.Params[1]),
+                static_cast<DWORD>(StackFrame.Params[2]),
+                static_cast<DWORD>(StackFrame.Params[3]));
+#endif
     // Verify the PC belongs to a module in this process.
-    if (!SymGetModuleBase(hProcess, PC)) {
+    if (!SymGetModuleBase64(hProcess, PC)) {
       fputs(" <unknown module>\n", stderr);
       continue;
     }
 
     // Print the symbol name.
     char buffer[512];
-    IMAGEHLP_SYMBOL *symbol = reinterpret_cast<IMAGEHLP_SYMBOL *>(buffer);
-    memset(symbol, 0, sizeof(IMAGEHLP_SYMBOL));
-    symbol->SizeOfStruct = sizeof(IMAGEHLP_SYMBOL);
-    symbol->MaxNameLength = 512 - sizeof(IMAGEHLP_SYMBOL);
+    IMAGEHLP_SYMBOL64 *symbol = reinterpret_cast<IMAGEHLP_SYMBOL64 *>(buffer);
+    memset(symbol, 0, sizeof(IMAGEHLP_SYMBOL64));
+    symbol->SizeOfStruct = sizeof(IMAGEHLP_SYMBOL64);
+    symbol->MaxNameLength = 512 - sizeof(IMAGEHLP_SYMBOL64);
 
-    DWORD dwDisp;
-    if (!SymGetSymFromAddr(hProcess, PC, &dwDisp, symbol)) {
+    DWORD64 dwDisp;
+    if (!SymGetSymFromAddr64(hProcess, PC, &dwDisp, symbol)) {
       fputc('\n', stderr);
       continue;
     }
 
     buffer[511] = 0;
     if (dwDisp > 0)
-      fprintf(stderr, ", %s()+%04lu bytes(s)", symbol->Name, dwDisp);
+      fprintf(stderr, ", %s() + 0x%llX bytes(s)", symbol->Name, dwDisp);
     else
       fprintf(stderr, ", %s", symbol->Name);
 
     // Print the source file and line number information.
-    IMAGEHLP_LINE line;
+    IMAGEHLP_LINE64 line;
+    DWORD dwLineDisp;
     memset(&line, 0, sizeof(line));
     line.SizeOfStruct = sizeof(line);
-    if (SymGetLineFromAddr(hProcess, PC, &dwDisp, &line)) {
+    if (SymGetLineFromAddr64(hProcess, PC, &dwLineDisp, &line)) {
       fprintf(stderr, ", %s, line %lu", line.FileName, line.LineNumber);
-      if (dwDisp > 0)
-        fprintf(stderr, "+%04lu byte(s)", dwDisp);
+      if (dwLineDisp > 0)
+        fprintf(stderr, " + 0x%lX byte(s)", dwLineDisp);
     }
 
     fputc('\n', stderr);
   }
 
-#endif
-
   if (ExitOnUnhandledExceptions)
     _exit(-3);
 
@@ -326,3 +477,12 @@ static BOOL WINAPI LLVMConsoleCtrlHandler(DWORD dwCtrlType) {
   LeaveCriticalSection(&CriticalSection);
   return FALSE;
 }
+
+#if __MINGW32__
+ // We turned these warnings off for this file so that MinGW-g++ doesn't
+ // complain about the ll format specifiers used.  Now we are turning the
+ // warnings back on.  If MinGW starts to support diagnostic stacks, we can
+ // replace this with a pop.
+ #pragma GCC diagnostic warning "-Wformat"
+ #pragma GCC diagnostic warning "-Wformat-extra-args"
+#endif
diff --git a/lib/Support/Windows/Windows.h b/lib/Support/Windows/Windows.h
index 4a1553b..67b6f01 100644
--- a/lib/Support/Windows/Windows.h
+++ b/lib/Support/Windows/Windows.h
@@ -19,9 +19,9 @@
 // mingw-w64 tends to define it as 0x0502 in its headers.
 #undef _WIN32_WINNT
 
-// Require at least Windows 2000 API.
-#define _WIN32_WINNT 0x0500
-#define _WIN32_IE    0x0500 // MinGW at it again.
+// Require at least Windows XP(5.1) API.
+#define _WIN32_WINNT 0x0501
+#define _WIN32_IE    0x0600 // MinGW at it again.
 #define WIN32_LEAN_AND_MEAN
 
 #include "llvm/Config/config.h" // Get build system configuration settings