Merge commit '7dfcb84fc16b3bf6b2379713b53090757f0a45f9'

Conflicts:
	docs/LangRef.rst
	include/llvm/CodeGen/CallingConvLower.h
	include/llvm/IRReader/IRReader.h
	include/llvm/Target/TargetMachine.h
	lib/CodeGen/CallingConvLower.cpp
	lib/IRReader/IRReader.cpp
	lib/IRReader/LLVMBuild.txt
	lib/IRReader/Makefile
	lib/LLVMBuild.txt
	lib/Makefile
	lib/Support/MemoryBuffer.cpp
	lib/Support/Unix/PathV2.inc
	lib/Target/ARM/ARMBaseInstrInfo.cpp
	lib/Target/ARM/ARMISelLowering.cpp
	lib/Target/ARM/ARMInstrInfo.td
	lib/Target/ARM/ARMSubtarget.cpp
	lib/Target/ARM/ARMTargetMachine.cpp
	lib/Target/Mips/CMakeLists.txt
	lib/Target/Mips/MipsDelaySlotFiller.cpp
	lib/Target/Mips/MipsISelLowering.cpp
	lib/Target/Mips/MipsInstrInfo.td
	lib/Target/Mips/MipsSubtarget.cpp
	lib/Target/Mips/MipsSubtarget.h
	lib/Target/X86/X86FastISel.cpp
	lib/Target/X86/X86ISelDAGToDAG.cpp
	lib/Target/X86/X86ISelLowering.cpp
	lib/Target/X86/X86InstrControl.td
	lib/Target/X86/X86InstrFormats.td
	lib/Transforms/IPO/ExtractGV.cpp
	lib/Transforms/InstCombine/InstCombineCompares.cpp
	lib/Transforms/Utils/SimplifyLibCalls.cpp
	test/CodeGen/X86/fast-isel-divrem.ll
	test/MC/ARM/data-in-code.ll
	tools/Makefile
	tools/llvm-extract/llvm-extract.cpp
	tools/llvm-link/CMakeLists.txt
	tools/opt/CMakeLists.txt
	tools/opt/LLVMBuild.txt
	tools/opt/Makefile
	tools/opt/opt.cpp

30 files changed, 799 insertions, 166 deletions

diff --git a/lib/Support/APFloat.cpp b/lib/Support/APFloat.cpp
index 5b68fbb270..6182e34150 100644
--- a/lib/Support/APFloat.cpp
+++ b/lib/Support/APFloat.cpp
@@ -3311,10 +3311,8 @@ namespace {
 
     significand = significand.udiv(divisor);
 
-    // Truncate the significand down to its active bit count, but
-    // don't try to drop below 32.
-    unsigned newPrecision = std::max(32U, significand.getActiveBits());
-    significand = significand.trunc(newPrecision);
+    // Truncate the significand down to its active bit count.
+    significand = significand.trunc(significand.getActiveBits());
   }
 
 
diff --git a/lib/Support/APInt.cpp b/lib/Support/APInt.cpp
index 07cb057b48..e8534753b4 100644
--- a/lib/Support/APInt.cpp
+++ b/lib/Support/APInt.cpp
@@ -559,12 +559,12 @@ bool APInt::slt(const APInt& RHS) const {
   if (lhsNeg) {
     // Sign bit is set so perform two's complement to make it positive
     lhs.flipAllBits();
-    lhs++;
+    ++lhs;
   }
   if (rhsNeg) {
     // Sign bit is set so perform two's complement to make it positive
     rhs.flipAllBits();
-    rhs++;
+    ++rhs;
   }
 
   // Now we have unsigned values to compare so do the comparison if necessary
@@ -2116,7 +2116,7 @@ void APInt::fromString(unsigned numbits, StringRef str, uint8_t radix) {
   }
   // If its negative, put it in two's complement form
   if (isNeg) {
-    (*this)--;
+    --(*this);
     this->flipAllBits();
   }
 }
@@ -2197,7 +2197,7 @@ void APInt::toString(SmallVectorImpl<char> &Str, unsigned Radix,
     // Flip the bits and add one to turn it into the equivalent positive
     // value and put a '-' in the result.
     Tmp.flipAllBits();
-    Tmp++;
+    ++Tmp;
     Str.push_back('-');
   }
 
diff --git a/lib/Support/CMakeLists.txt b/lib/Support/CMakeLists.txt
index 5ba69fc3c8..01565c5776 100644
--- a/lib/Support/CMakeLists.txt
+++ b/lib/Support/CMakeLists.txt
@@ -7,6 +7,7 @@ add_llvm_library(LLVMSupport
   BranchProbability.cpp
   circular_raw_ostream.cpp
   CommandLine.cpp
+  Compression.cpp
   ConstantRange.cpp
   ConvertUTF.c
   ConvertUTFWrapper.cpp
@@ -83,6 +84,7 @@ add_llvm_library(LLVMSupport
   Threading.cpp
   TimeValue.cpp
   Valgrind.cpp
+  Watchdog.cpp
   Unix/Host.inc
   Unix/Memory.inc
   Unix/Mutex.inc
@@ -95,6 +97,7 @@ add_llvm_library(LLVMSupport
   Unix/system_error.inc
   Unix/ThreadLocal.inc
   Unix/TimeValue.inc
+  Unix/Watchdog.inc
   Windows/DynamicLibrary.inc
   Windows/Host.inc
   Windows/Memory.inc
@@ -108,4 +111,5 @@ add_llvm_library(LLVMSupport
   Windows/system_error.inc
   Windows/ThreadLocal.inc
   Windows/TimeValue.inc
+  Windows/Watchdog.inc
   )
diff --git a/lib/Support/CommandLine.cpp b/lib/Support/CommandLine.cpp
index 53fcf06f82..18d3db527b 100644
--- a/lib/Support/CommandLine.cpp
+++ b/lib/Support/CommandLine.cpp
@@ -33,6 +33,7 @@
 #include "llvm/Support/system_error.h"
 #include <cerrno>
 #include <cstdlib>
+#include <map>
 using namespace llvm;
 using namespace cl;
 
@@ -106,6 +107,17 @@ void Option::addArgument() {
   MarkOptionsChanged();
 }
 
+// This collects the different option categories that have been registered.
+typedef SmallPtrSet<OptionCategory*,16> OptionCatSet;
+static ManagedStatic<OptionCatSet> RegisteredOptionCategories;
+
+// Initialise the general option category.
+OptionCategory llvm::cl::GeneralCategory("General options");
+
+void OptionCategory::registerCategory()
+{
+  RegisteredOptionCategories->insert(this);
+}
 
 //===----------------------------------------------------------------------===//
 // Basic, shared command line option processing machinery.
@@ -1222,15 +1234,20 @@ sortOpts(StringMap<Option*> &OptMap,
 namespace {
 
 class HelpPrinter {
-  size_t MaxArgLen;
-  const Option *EmptyArg;
+protected:
   const bool ShowHidden;
+  typedef SmallVector<std::pair<const char *, Option*>,128> StrOptionPairVector;
+  // Print the options. Opts is assumed to be alphabetically sorted.
+  virtual void printOptions(StrOptionPairVector &Opts, size_t MaxArgLen) {
+    for (size_t i = 0, e = Opts.size(); i != e; ++i)
+      Opts[i].second->printOptionInfo(MaxArgLen);
+  }
 
 public:
-  explicit HelpPrinter(bool showHidden) : ShowHidden(showHidden) {
-    EmptyArg = 0;
-  }
+  explicit HelpPrinter(bool showHidden) : ShowHidden(showHidden) {}
+  virtual ~HelpPrinter() {}
 
+  // Invoke the printer.
   void operator=(bool Value) {
     if (Value == false) return;
 
@@ -1240,7 +1257,7 @@ public:
     StringMap<Option*> OptMap;
     GetOptionInfo(PositionalOpts, SinkOpts, OptMap);
 
-    SmallVector<std::pair<const char *, Option*>, 128> Opts;
+    StrOptionPairVector Opts;
     sortOpts(OptMap, Opts, ShowHidden);
 
     if (ProgramOverview)
@@ -1266,17 +1283,17 @@ public:
     outs() << "\n\n";
 
     // Compute the maximum argument length...
-    MaxArgLen = 0;
+    size_t MaxArgLen = 0;
     for (size_t i = 0, e = Opts.size(); i != e; ++i)
       MaxArgLen = std::max(MaxArgLen, Opts[i].second->getOptionWidth());
 
     outs() << "OPTIONS:\n";
-    for (size_t i = 0, e = Opts.size(); i != e; ++i)
-      Opts[i].second->printOptionInfo(MaxArgLen);
+    printOptions(Opts, MaxArgLen);
 
     // Print any extra help the user has declared.
     for (std::vector<const char *>::iterator I = MoreHelp->begin(),
-          E = MoreHelp->end(); I != E; ++I)
+                                             E = MoreHelp->end();
+         I != E; ++I)
       outs() << *I;
     MoreHelp->clear();
 
@@ -1284,21 +1301,152 @@ public:
     exit(1);
   }
 };
+
+class CategorizedHelpPrinter : public HelpPrinter {
+public:
+  explicit CategorizedHelpPrinter(bool showHidden) : HelpPrinter(showHidden) {}
+
+  // Helper function for printOptions().
+  // It shall return true if A's name should be lexographically
+  // ordered before B's name. It returns false otherwise.
+  static bool OptionCategoryCompare(OptionCategory *A, OptionCategory *B) {
+    int Length = strcmp(A->getName(), B->getName());
+    assert(Length != 0 && "Duplicate option categories");
+    return Length < 0;
+  }
+
+  // Make sure we inherit our base class's operator=()
+  using HelpPrinter::operator= ;
+
+protected:
+  virtual void printOptions(StrOptionPairVector &Opts, size_t MaxArgLen) {
+    std::vector<OptionCategory *> SortedCategories;
+    std::map<OptionCategory *, std::vector<Option *> > CategorizedOptions;
+
+    // Collect registered option categories into vector in preperation for
+    // sorting.
+    for (OptionCatSet::const_iterator I = RegisteredOptionCategories->begin(),
+                                      E = RegisteredOptionCategories->end();
+         I != E; ++I)
+      SortedCategories.push_back(*I);
+
+    // Sort the different option categories alphabetically.
+    assert(SortedCategories.size() > 0 && "No option categories registered!");
+    std::sort(SortedCategories.begin(), SortedCategories.end(),
+              OptionCategoryCompare);
+
+    // Create map to empty vectors.
+    for (std::vector<OptionCategory *>::const_iterator
+             I = SortedCategories.begin(),
+             E = SortedCategories.end();
+         I != E; ++I)
+      CategorizedOptions[*I] = std::vector<Option *>();
+
+    // Walk through pre-sorted options and assign into categories.
+    // Because the options are already alphabetically sorted the
+    // options within categories will also be alphabetically sorted.
+    for (size_t I = 0, E = Opts.size(); I != E; ++I) {
+      Option *Opt = Opts[I].second;
+      assert(CategorizedOptions.count(Opt->Category) > 0 &&
+             "Option has an unregistered category");
+      CategorizedOptions[Opt->Category].push_back(Opt);
+    }
+
+    // Now do printing.
+    for (std::vector<OptionCategory *>::const_iterator
+             Category = SortedCategories.begin(),
+             E = SortedCategories.end();
+         Category != E; ++Category) {
+      // Hide empty categories for -help, but show for -help-hidden.
+      bool IsEmptyCategory = CategorizedOptions[*Category].size() == 0;
+      if (!ShowHidden && IsEmptyCategory)
+        continue;
+
+      // Print category information.
+      outs() << "\n";
+      outs() << (*Category)->getName() << ":\n";
+
+      // Check if description is set.
+      if ((*Category)->getDescription() != 0)
+        outs() << (*Category)->getDescription() << "\n\n";
+      else
+        outs() << "\n";
+
+      // When using -help-hidden explicitly state if the category has no
+      // options associated with it.
+      if (IsEmptyCategory) {
+        outs() << "  This option category has no options.\n";
+        continue;
+      }
+      // Loop over the options in the category and print.
+      for (std::vector<Option *>::const_iterator
+               Opt = CategorizedOptions[*Category].begin(),
+               E = CategorizedOptions[*Category].end();
+           Opt != E; ++Opt)
+        (*Opt)->printOptionInfo(MaxArgLen);
+    }
+  }
+};
+
+// This wraps the Uncategorizing and Categorizing printers and decides
+// at run time which should be invoked.
+class HelpPrinterWrapper {
+private:
+  HelpPrinter &UncategorizedPrinter;
+  CategorizedHelpPrinter &CategorizedPrinter;
+
+public:
+  explicit HelpPrinterWrapper(HelpPrinter &UncategorizedPrinter,
+                              CategorizedHelpPrinter &CategorizedPrinter) :
+    UncategorizedPrinter(UncategorizedPrinter),
+    CategorizedPrinter(CategorizedPrinter) { }
+
+  // Invoke the printer.
+  void operator=(bool Value);
+};
+
 } // End anonymous namespace
 
-// Define the two HelpPrinter instances that are used to print out help, or
-// help-hidden...
-//
-static HelpPrinter NormalPrinter(false);
-static HelpPrinter HiddenPrinter(true);
+// Declare the four HelpPrinter instances that are used to print out help, or
+// help-hidden as an uncategorized list or in categories.
+static HelpPrinter UncategorizedNormalPrinter(false);
+static HelpPrinter UncategorizedHiddenPrinter(true);
+static CategorizedHelpPrinter CategorizedNormalPrinter(false);
+static CategorizedHelpPrinter CategorizedHiddenPrinter(true);
+
 
+// Declare HelpPrinter wrappers that will decide whether or not to invoke
+// a categorizing help printer
+static HelpPrinterWrapper WrappedNormalPrinter(UncategorizedNormalPrinter,
+                                               CategorizedNormalPrinter);
+static HelpPrinterWrapper WrappedHiddenPrinter(UncategorizedHiddenPrinter,
+                                               CategorizedHiddenPrinter);
+
+// Define uncategorized help printers.
+// -help-list is hidden by default because if Option categories are being used
+// then -help behaves the same as -help-list.
 static cl::opt<HelpPrinter, true, parser<bool> >
-HOp("help", cl::desc("Display available options (-help-hidden for more)"),
-    cl::location(NormalPrinter), cl::ValueDisallowed);
+HLOp("help-list",
+     cl::desc("Display list of available options (-help-list-hidden for more)"),
+     cl::location(UncategorizedNormalPrinter), cl::Hidden, cl::ValueDisallowed);
 
 static cl::opt<HelpPrinter, true, parser<bool> >
+HLHOp("help-list-hidden",
+     cl::desc("Display list of all available options"),
+     cl::location(UncategorizedHiddenPrinter), cl::Hidden, cl::ValueDisallowed);
+
+// Define uncategorized/categorized help printers. These printers change their
+// behaviour at runtime depending on whether one or more Option categories have
+// been declared.
+static cl::opt<HelpPrinterWrapper, true, parser<bool> >
+HOp("help", cl::desc("Display available options (-help-hidden for more)"),
+    cl::location(WrappedNormalPrinter), cl::ValueDisallowed);
+
+static cl::opt<HelpPrinterWrapper, true, parser<bool> >
 HHOp("help-hidden", cl::desc("Display all available options"),
-     cl::location(HiddenPrinter), cl::Hidden, cl::ValueDisallowed);
+     cl::location(WrappedHiddenPrinter), cl::Hidden, cl::ValueDisallowed);
+
+
 
 static cl::opt<bool>
 PrintOptions("print-options",
@@ -1310,6 +1458,24 @@ PrintAllOptions("print-all-options",
                 cl::desc("Print all option values after command line parsing"),
                 cl::Hidden, cl::init(false));
 
+void HelpPrinterWrapper::operator=(bool Value) {
+  if (Value == false)
+    return;
+
+  // Decide which printer to invoke. If more than one option category is
+  // registered then it is useful to show the categorized help instead of
+  // uncategorized help.
+  if (RegisteredOptionCategories->size() > 1) {
+    // unhide -help-list option so user can have uncategorized output if they
+    // want it.
+    HLOp.setHiddenFlag(NotHidden);
+
+    CategorizedPrinter = true; // Invoke categorized printer
+  }
+  else
+    UncategorizedPrinter = true; // Invoke uncategorized printer
+}
+
 // Print the value of each option.
 void cl::PrintOptionValues() {
   if (!PrintOptions && !PrintAllOptions) return;
@@ -1397,14 +1563,22 @@ VersOp("version", cl::desc("Display the version of this program"),
     cl::location(VersionPrinterInstance), cl::ValueDisallowed);
 
 // Utility function for printing the help message.
-void cl::PrintHelpMessage() {
-  // This looks weird, but it actually prints the help message. The
-  // NormalPrinter variable is a HelpPrinter and the help gets printed when
-  // its operator= is invoked. That's because the "normal" usages of the
-  // help printer is to be assigned true/false depending on whether the
-  // -help option was given or not. Since we're circumventing that we have
-  // to make it look like -help was given, so we assign true.
-  NormalPrinter = true;
+void cl::PrintHelpMessage(bool Hidden, bool Categorized) {
+  // This looks weird, but it actually prints the help message. The Printers are
+  // types of HelpPrinter and the help gets printed when its operator= is
+  // invoked. That's because the "normal" usages of the help printer is to be
+  // assigned true/false depending on whether -help or -help-hidden was given or
+  // not.  Since we're circumventing that we have to make it look like -help or
+  // -help-hidden were given, so we assign true.
+
+  if (!Hidden && !Categorized)
+    UncategorizedNormalPrinter = true;
+  else if (!Hidden && Categorized)
+    CategorizedNormalPrinter = true;
+  else if (Hidden && !Categorized)
+    UncategorizedHiddenPrinter = true;
+  else
+    CategorizedHiddenPrinter = true;
 }
 
 /// Utility function for printing version number.
@@ -1422,3 +1596,13 @@ void cl::AddExtraVersionPrinter(void (*func)()) {
 
   ExtraVersionPrinters->push_back(func);
 }
+
+void cl::getRegisteredOptions(StringMap<Option*> &Map)
+{
+  // Get all the options.
+  SmallVector<Option*, 4> PositionalOpts; //NOT USED
+  SmallVector<Option*, 4> SinkOpts;  //NOT USED
+  assert(Map.size() == 0 && "StringMap must be empty");
+  GetOptionInfo(PositionalOpts, SinkOpts, Map);
+  return;
+}
diff --git a/lib/Support/Compression.cpp b/lib/Support/Compression.cpp
new file mode 100644
index 0000000000..fd8a8743ea
--- /dev/null
+++ b/lib/Support/Compression.cpp
@@ -0,0 +1,97 @@
+//===--- Compression.cpp - Compression implementation ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file implements compression functions.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/Compression.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Config/config.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MemoryBuffer.h"
+#if LLVM_ENABLE_ZLIB == 1 && HAVE_ZLIB_H
+#include <zlib.h>
+#endif
+
+using namespace llvm;
+
+#if LLVM_ENABLE_ZLIB == 1 && HAVE_LIBZ
+static int encodeZlibCompressionLevel(zlib::CompressionLevel Level) {
+  switch (Level) {
+    case zlib::NoCompression: return 0;
+    case zlib::BestSpeedCompression: return 1;
+    case zlib::DefaultCompression: return Z_DEFAULT_COMPRESSION;
+    case zlib::BestSizeCompression: return 9;
+  }
+  llvm_unreachable("Invalid zlib::CompressionLevel!");
+}
+
+static zlib::Status encodeZlibReturnValue(int ReturnValue) {
+  switch (ReturnValue) {
+    case Z_OK: return zlib::StatusOK;
+    case Z_MEM_ERROR: return zlib::StatusOutOfMemory;
+    case Z_BUF_ERROR: return zlib::StatusBufferTooShort;
+    case Z_STREAM_ERROR: return zlib::StatusInvalidArg;
+    case Z_DATA_ERROR: return zlib::StatusInvalidData;
+    default: llvm_unreachable("unknown zlib return status!");
+  }
+}
+
+bool zlib::isAvailable() { return true; }
+zlib::Status zlib::compress(StringRef InputBuffer,
+                            OwningPtr<MemoryBuffer> &CompressedBuffer,
+                            CompressionLevel Level) {
+  unsigned long CompressedSize = ::compressBound(InputBuffer.size());
+  OwningArrayPtr<char> TmpBuffer(new char[CompressedSize]);
+  int CLevel = encodeZlibCompressionLevel(Level);
+  Status Res = encodeZlibReturnValue(::compress2(
+      (Bytef *)TmpBuffer.get(), &CompressedSize,
+      (const Bytef *)InputBuffer.data(), InputBuffer.size(), CLevel));
+  if (Res == StatusOK) {
+    CompressedBuffer.reset(MemoryBuffer::getMemBufferCopy(
+        StringRef(TmpBuffer.get(), CompressedSize)));
+    // Tell MSan that memory initialized by zlib is valid.
+    __msan_unpoison(CompressedBuffer->getBufferStart(), CompressedSize);
+  }
+  return Res;
+}
+
+zlib::Status zlib::uncompress(StringRef InputBuffer,
+                              OwningPtr<MemoryBuffer> &UncompressedBuffer,
+                              size_t UncompressedSize) {
+  OwningArrayPtr<char> TmpBuffer(new char[UncompressedSize]);
+  Status Res = encodeZlibReturnValue(
+      ::uncompress((Bytef *)TmpBuffer.get(), (uLongf *)&UncompressedSize,
+                   (const Bytef *)InputBuffer.data(), InputBuffer.size()));
+  if (Res == StatusOK) {
+    UncompressedBuffer.reset(MemoryBuffer::getMemBufferCopy(
+        StringRef(TmpBuffer.get(), UncompressedSize)));
+    // Tell MSan that memory initialized by zlib is valid.
+    __msan_unpoison(UncompressedBuffer->getBufferStart(), UncompressedSize);
+  }
+  return Res;
+}
+
+#else
+bool zlib::isAvailable() { return false; }
+zlib::Status zlib::compress(StringRef InputBuffer,
+                            OwningPtr<MemoryBuffer> &CompressedBuffer,
+                            CompressionLevel Level) {
+  return zlib::StatusUnsupported;
+}
+zlib::Status zlib::uncompress(StringRef InputBuffer,
+                              OwningPtr<MemoryBuffer> &UncompressedBuffer,
+                              size_t UncompressedSize) {
+  return zlib::StatusUnsupported;
+}
+#endif
+
diff --git a/lib/Support/DataExtractor.cpp b/lib/Support/DataExtractor.cpp
index 3d5cce0535..a564d211b1 100644
--- a/lib/Support/DataExtractor.cpp
+++ b/lib/Support/DataExtractor.cpp
@@ -20,7 +20,7 @@ static T getU(uint32_t *offset_ptr, const DataExtractor *de,
   uint32_t offset = *offset_ptr;
   if (de->isValidOffsetForDataOfSize(offset, sizeof(val))) {
     std::memcpy(&val, &Data[offset], sizeof(val));
-    if (sys::isLittleEndianHost() != isLittleEndian)
+    if (sys::IsLittleEndianHost != isLittleEndian)
       val = sys::SwapByteOrder(val);
 
     // Advance the offset
diff --git a/lib/Support/ErrorHandling.cpp b/lib/Support/ErrorHandling.cpp
index d4382e54e0..f4b591e777 100644
--- a/lib/Support/ErrorHandling.cpp
+++ b/lib/Support/ErrorHandling.cpp
@@ -49,21 +49,21 @@ void llvm::remove_fatal_error_handler() {
   ErrorHandler = 0;
 }
 
-void llvm::report_fatal_error(const char *Reason) {
-  report_fatal_error(Twine(Reason));
+void llvm::report_fatal_error(const char *Reason, bool GenCrashDiag) {
+  report_fatal_error(Twine(Reason), GenCrashDiag);
 }
 
-void llvm::report_fatal_error(const std::string &Reason) {
-  report_fatal_error(Twine(Reason));
+void llvm::report_fatal_error(const std::string &Reason, bool GenCrashDiag) {
+  report_fatal_error(Twine(Reason), GenCrashDiag);
 }
 
-void llvm::report_fatal_error(StringRef Reason) {
-  report_fatal_error(Twine(Reason));
+void llvm::report_fatal_error(StringRef Reason, bool GenCrashDiag) {
+  report_fatal_error(Twine(Reason), GenCrashDiag);
 }
 
-void llvm::report_fatal_error(const Twine &Reason) {
+void llvm::report_fatal_error(const Twine &Reason, bool GenCrashDiag) {
   if (ErrorHandler) {
-    ErrorHandler(ErrorHandlerUserData, Reason.str());
+    ErrorHandler(ErrorHandlerUserData, Reason.str(), GenCrashDiag);
   } else {
     // Blast the result out to stderr.  We don't try hard to make sure this
     // succeeds (e.g. handling EINTR) and we can't use errs() here because
diff --git a/lib/Support/FileOutputBuffer.cpp b/lib/Support/FileOutputBuffer.cpp
index cd430f218b..1ee69b6023 100644
--- a/lib/Support/FileOutputBuffer.cpp
+++ b/lib/Support/FileOutputBuffer.cpp
@@ -70,8 +70,8 @@ error_code FileOutputBuffer::create(StringRef FilePath,
   if (EC)
     return EC;
 
-  OwningPtr<mapped_file_region> MappedFile(
-    new mapped_file_region(FD, mapped_file_region::readwrite, Size, 0, EC));
+  OwningPtr<mapped_file_region> MappedFile(new mapped_file_region(
+      FD, true, mapped_file_region::readwrite, Size, 0, EC));
   if (EC)
     return EC;
 
diff --git a/lib/Support/FoldingSet.cpp b/lib/Support/FoldingSet.cpp
index 36e33b5aaf..145f12dc1e 100644
--- a/lib/Support/FoldingSet.cpp
+++ b/lib/Support/FoldingSet.cpp
@@ -101,7 +101,7 @@ void FoldingSetNodeID::AddString(StringRef String) {
     // Otherwise do it the hard way.
     // To be compatible with above bulk transfer, we need to take endianness
     // into account.
-    if (sys::isBigEndianHost()) {
+    if (sys::IsBigEndianHost) {
       for (Pos += 4; Pos <= Size; Pos += 4) {
         unsigned V = ((unsigned char)String[Pos - 4] << 24) |
                      ((unsigned char)String[Pos - 3] << 16) |
@@ -110,7 +110,7 @@ void FoldingSetNodeID::AddString(StringRef String) {
         Bits.push_back(V);
       }
     } else {
-      assert(sys::isLittleEndianHost() && "Unexpected host endianness");
+      assert(sys::IsLittleEndianHost && "Unexpected host endianness");
       for (Pos += 4; Pos <= Size; Pos += 4) {
         unsigned V = ((unsigned char)String[Pos - 1] << 24) |
                      ((unsigned char)String[Pos - 2] << 16) |
diff --git a/lib/Support/Host.cpp b/lib/Support/Host.cpp
index b9bbcb9322..a7c7a95800 100644
--- a/lib/Support/Host.cpp
+++ b/lib/Support/Host.cpp
@@ -112,6 +112,21 @@ static bool GetX86CpuIDAndInfo(unsigned value, unsigned *rEAX,
 #endif
 }
 
+static bool OSHasAVXSupport() {
+#if defined(__GNUC__)
+  // Check xgetbv; this uses a .byte sequence instead of the instruction
+  // directly because older assemblers do not include support for xgetbv and
+  // there is no easy way to conditionally compile based on the assembler used.
+  int rEAX, rEDX;
+  __asm__ (".byte 0x0f, 0x01, 0xd0" : "=a" (rEAX), "=d" (rEDX) : "c" (0));
+#elif defined(_MSC_FULL_VER) && defined(_XCR_XFEATURE_ENABLED_MASK)
+  unsigned long long rEAX = _xgetbv(_XCR_XFEATURE_ENABLED_MASK);
+#else
+  int rEAX = 0; // Ensures we return false
+#endif
+  return (rEAX & 6) == 6;
+}
+
 static void DetectX86FamilyModel(unsigned EAX, unsigned &Family,
                                  unsigned &Model) {
   Family = (EAX >> 8) & 0xf; // Bits 8 - 11
@@ -134,6 +149,11 @@ std::string sys::getHostCPUName() {
   DetectX86FamilyModel(EAX, Family, Model);
 
   bool HasSSE3 = (ECX & 0x1);
+  // If CPUID indicates support for XSAVE, XRESTORE and AVX, and XGETBV 
+  // indicates that the AVX registers will be saved and restored on context
+  // switch, then we have full AVX support.
+  const unsigned AVXBits = (1 << 27) | (1 << 28);
+  bool HasAVX = ((ECX & AVXBits) == AVXBits) && OSHasAVXSupport();
   GetX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
   bool Em64T = (EDX >> 29) & 0x1;
 
@@ -243,11 +263,15 @@ std::string sys::getHostCPUName() {
       case 42: // Intel Core i7 processor. All processors are manufactured
                // using the 32 nm process.
       case 45:
-        return "corei7-avx";
+        // Not all Sandy Bridge processors support AVX (such as the Pentium
+        // versions instead of the i7 versions).
+        return HasAVX ? "corei7-avx" : "corei7";
 
       // Ivy Bridge:
       case 58:
-        return "core-avx-i";
+        // Not all Ivy Bridge processors support AVX (such as the Pentium
+        // versions instead of the i7 versions).
+        return HasAVX ? "core-avx-i" : "corei7";
 
       case 28: // Most 45 nm Intel Atom processors
       case 38: // 45 nm Atom Lincroft
@@ -331,10 +355,15 @@ std::string sys::getHostCPUName() {
       case 20:
         return "btver1";
       case 21:
-        if (Model <= 15)
-          return "bdver1";
-        else if (Model <= 31)
+        if (!HasAVX) // If the OS doesn't support AVX provide a sane fallback.
+          return "btver1";
+        if (Model > 15 && Model <= 31)
           return "bdver2";
+        return "bdver1";
+      case 22:
+        if (!HasAVX) // If the OS doesn't support AVX provide a sane fallback.
+          return "btver1";
+        return "btver2";
     default:
       return "generic";
     }
@@ -584,7 +613,7 @@ bool sys::getHostCPUFeatures(StringMap<bool> &Features){
 #endif
 
 std::string sys::getProcessTriple() {
-  Triple PT(LLVM_HOSTTRIPLE);
+  Triple PT(LLVM_HOST_TRIPLE);
 
   if (sizeof(void *) == 8 && PT.isArch32Bit())
     PT = PT.get64BitArchVariant();
diff --git a/lib/Support/LockFileManager.cpp b/lib/Support/LockFileManager.cpp
index f49d025c11..819d25546b 100644
--- a/lib/Support/LockFileManager.cpp
+++ b/lib/Support/LockFileManager.cpp
@@ -174,8 +174,8 @@ void LockFileManager::waitForUnlock() {
   Interval.tv_sec = 0;
   Interval.tv_nsec = 1000000;
 #endif
-  // Don't wait more than an hour for the file to appear.
-  const unsigned MaxSeconds = 3600;
+  // Don't wait more than five minutes for the file to appear.
+  unsigned MaxSeconds = 300;
   bool LockFileGone = false;
   do {
     // Sleep for the designated interval, to allow the owning process time to
@@ -187,21 +187,48 @@ void LockFileManager::waitForUnlock() {
 #else
     nanosleep(&Interval, NULL);
 #endif
-    // If the lock file no longer exists, wait for the actual file.
     bool Exists = false;
+    bool LockFileJustDisappeared = false;
+
+    // If the lock file is still expected to be there, check whether it still
+    // is.
     if (!LockFileGone) {
       if (!sys::fs::exists(LockFileName.str(), Exists) && !Exists) {
         LockFileGone = true;
+        LockFileJustDisappeared = true;
         Exists = false;
       }
     }
+
+    // If the lock file is no longer there, check if the original file is
+    // available now.
     if (LockFileGone) {
-      if (!sys::fs::exists(FileName.str(), Exists) && Exists)
+      if (!sys::fs::exists(FileName.str(), Exists) && Exists) {
         return;
+      }
+
+      // The lock file is gone, so now we're waiting for the original file to
+      // show up. If this just happened, reset our waiting intervals and keep
+      // waiting.
+      if (LockFileJustDisappeared) {
+        MaxSeconds = 5;
+
+#if LLVM_ON_WIN32
+        Interval = 1;
+#else
+        Interval.tv_sec = 0;
+        Interval.tv_nsec = 1000000;
+#endif
+        continue;
+      }
     }
 
-    if (!processStillExecuting((*Owner).first, (*Owner).second))
+    // If we're looking for the lock file to disappear, but the process
+    // owning the lock died without cleaning up, just bail out.
+    if (!LockFileGone &&
+        !processStillExecuting((*Owner).first, (*Owner).second)) {
       return;
+    }
 
     // Exponentially increase the time we wait for the lock to be removed.
 #if LLVM_ON_WIN32
diff --git a/lib/Support/MemoryBuffer.cpp b/lib/Support/MemoryBuffer.cpp
index 265f14ad48..7a8b0ecd3d 100644
--- a/lib/Support/MemoryBuffer.cpp
+++ b/lib/Support/MemoryBuffer.cpp
@@ -72,13 +72,17 @@ static void CopyStringRef(char *Memory, StringRef Data) {
   Memory[Data.size()] = 0; // Null terminate string.
 }
 
-/// GetNamedBuffer - Allocates a new MemoryBuffer with Name copied after it.
-template <typename T>
-static T *GetNamedBuffer(StringRef Buffer, StringRef Name,
-                         bool RequiresNullTerminator) {
-  char *Mem = static_cast<char*>(operator new(sizeof(T) + Name.size() + 1));
-  CopyStringRef(Mem + sizeof(T), Name);
-  return new (Mem) T(Buffer, RequiresNullTerminator);
+namespace {
+struct NamedBufferAlloc {
+  StringRef Name;
+  NamedBufferAlloc(StringRef Name) : Name(Name) {}
+};
+}
+
+void *operator new(size_t N, const NamedBufferAlloc &Alloc) {
+  char *Mem = static_cast<char *>(operator new(N + Alloc.Name.size() + 1));
+  CopyStringRef(Mem + N, Alloc.Name);
+  return Mem;
 }
 
 namespace {
@@ -105,8 +109,8 @@ public:
 MemoryBuffer *MemoryBuffer::getMemBuffer(StringRef InputData,
                                          StringRef BufferName,
                                          bool RequiresNullTerminator) {
-  return GetNamedBuffer<MemoryBufferMem>(InputData, BufferName,
-                                         RequiresNullTerminator);
+  return new (NamedBufferAlloc(BufferName))
+      MemoryBufferMem(InputData, RequiresNullTerminator);
 }
 
 /// getMemBufferCopy - Open the specified memory range as a MemoryBuffer,
@@ -183,24 +187,38 @@ error_code MemoryBuffer::getFileOrSTDIN(const char *Filename,
 //===----------------------------------------------------------------------===//
 
 namespace {
-/// MemoryBufferMMapFile - This represents a file that was mapped in with the
-/// sys::Path::MapInFilePages method.  When destroyed, it calls the
-/// sys::Path::UnMapFilePages method.
-class MemoryBufferMMapFile : public MemoryBufferMem {
-public:
-  MemoryBufferMMapFile(StringRef Buffer, bool RequiresNullTerminator)
-    : MemoryBufferMem(Buffer, RequiresNullTerminator) { }
+/// \brief Memorry maps a file descriptor using sys::fs::mapped_file_region.
+///
+/// This handles converting the offset into a legal offset on the platform.
+class MemoryBufferMMapFile : public MemoryBuffer {
+  sys::fs::mapped_file_region MFR;
+
+  static uint64_t getLegalMapOffset(uint64_t Offset) {
+    return Offset & ~(sys::fs::mapped_file_region::alignment() - 1);
+  }
+
+  static uint64_t getLegalMapSize(uint64_t Len, uint64_t Offset) {
+    return Len + (Offset - getLegalMapOffset(Offset));
+  }
 
-  ~MemoryBufferMMapFile() {
-    static int PageSize = sys::process::get_self()->page_size();
+  const char *getStart(uint64_t Len, uint64_t Offset) {
+    return MFR.const_data() + (Offset - getLegalMapOffset(Offset));
+  }
 
-    uintptr_t Start = reinterpret_cast<uintptr_t>(getBufferStart());
-    size_t Size = getBufferSize();
-    uintptr_t RealStart = Start & ~(PageSize - 1);
-    size_t RealSize = Size + (Start - RealStart);
+public:
+  MemoryBufferMMapFile(bool RequiresNullTerminator, int FD, uint64_t Len,
+                       uint64_t Offset, error_code EC)
+      : MFR(FD, false, sys::fs::mapped_file_region::readonly,
+            getLegalMapSize(Len, Offset), getLegalMapOffset(Offset), EC) {
+    if (!EC) {
+      const char *Start = getStart(Len, Offset);
+      init(Start, Start + Len, RequiresNullTerminator);
+    }
+  }
 
-    sys::Path::UnMapFilePages(reinterpret_cast<const char*>(RealStart),
-                              RealSize);
+  virtual const char *getBufferIdentifier() const LLVM_OVERRIDE {
+    // The name is stored after the class itself.
+    return reinterpret_cast<const char *>(this + 1);
   }
 
   virtual BufferKind getBufferKind() const LLVM_OVERRIDE {
@@ -244,6 +262,8 @@ error_code MemoryBuffer::getFile(const char *Filename,
                                  OwningPtr<MemoryBuffer> &result,
                                  int64_t FileSize,
                                  bool RequiresNullTerminator) {
+  // FIXME: Review if this check is unnecessary on windows as well.
+#ifdef LLVM_ON_WIN32
   // First check that the "file" is not a directory
   bool is_dir = false;
   error_code err = sys::fs::is_directory(Filename, is_dir);
@@ -251,6 +271,7 @@ error_code MemoryBuffer::getFile(const char *Filename,
     return err;
   if (is_dir)
     return make_error_code(errc::is_a_directory);
+#endif
 
   int OpenFlags = O_RDONLY;
 #ifdef O_BINARY
@@ -269,7 +290,7 @@ error_code MemoryBuffer::getFile(const char *Filename,
 static bool shouldUseMmap(int FD,
                           size_t FileSize,
                           size_t MapSize,
-                          int64_t Offset,
+                          int64_t Offset,   // @LOCALMOD (?)
                           bool RequiresNullTerminator,
                           int PageSize) {
   // We don't use mmap for small files because this can severely fragment our
@@ -280,6 +301,7 @@ static bool shouldUseMmap(int FD,
   if (!RequiresNullTerminator)
     return true;
 
+
   // If we don't know the file size, use fstat to find out.  fstat on an open
   // file descriptor is cheaper than stat on a random path.
   // FIXME: this chunk of code is duplicated, but it avoids a fstat when
@@ -340,17 +362,11 @@ error_code MemoryBuffer::getOpenFile(int FD, const char *Filename,
 
   if (shouldUseMmap(FD, FileSize, MapSize, Offset, RequiresNullTerminator,
                     PageSize)) {
-    int64_t RealMapOffset = Offset & ~(PageSize - 1);
-    int64_t Delta = Offset - RealMapOffset;
-    size_t RealMapSize = MapSize + Delta;
-
-    if (const char *Pages = sys::Path::MapInFilePages(FD,
-                                                      RealMapSize,
-                                                      RealMapOffset)) {
-      result.reset(GetNamedBuffer<MemoryBufferMMapFile>(
-          StringRef(Pages + Delta, MapSize), Filename, RequiresNullTerminator));
+    error_code EC;
+    result.reset(new (NamedBufferAlloc(Filename)) MemoryBufferMMapFile(
+        RequiresNullTerminator, FD, MapSize, Offset, EC));
+    if (!EC)
       return error_code::success();
-    }
   }
 
   MemoryBuffer *Buf = MemoryBuffer::getNewUninitMemBuffer(MapSize, Filename);
diff --git a/lib/Support/PathV2.cpp b/lib/Support/PathV2.cpp
index 41add96194..ac53a9e9e6 100644
--- a/lib/Support/PathV2.cpp
+++ b/lib/Support/PathV2.cpp
@@ -18,6 +18,9 @@
 #include <cctype>
 #include <cstdio>
 #include <cstring>
+#ifdef __APPLE__
+#include <unistd.h>
+#endif
 
 namespace {
   using llvm::StringRef;
@@ -493,6 +496,27 @@ bool is_separator(char value) {
 void system_temp_directory(bool erasedOnReboot, SmallVectorImpl<char> &result) {
   result.clear();
 
+#ifdef __APPLE__
+  // On Darwin, use DARWIN_USER_TEMP_DIR or DARWIN_USER_CACHE_DIR.
+  int ConfName = erasedOnReboot? _CS_DARWIN_USER_TEMP_DIR
+                               : _CS_DARWIN_USER_CACHE_DIR;
+  size_t ConfLen = confstr(ConfName, 0, 0);
+  if (ConfLen > 0) {
+    do {
+      result.resize(ConfLen);
+      ConfLen = confstr(ConfName, result.data(), result.size());
+    } while (ConfLen > 0 && ConfLen != result.size());
+
+    if (ConfLen > 0) {
+      assert(result.back() == 0);
+      result.pop_back();
+      return;
+    }
+
+    result.clear();
+  }
+#endif
+
   // Check whether the temporary directory is specified by an environment
   // variable.
   const char *EnvironmentVariable;
@@ -765,8 +789,11 @@ file_magic identify_magic(StringRef magic) {
 
     case '\177':
       if (magic[1] == 'E' && magic[2] == 'L' && magic[3] == 'F') {
-        if (magic.size() >= 18 && magic[17] == 0)
-          switch (magic[16]) {
+        bool Data2MSB = magic[5] == 2;
+        unsigned high = Data2MSB ? 16 : 17;
+        unsigned low  = Data2MSB ? 17 : 16;
+        if (magic.size() >= 18 && magic[high] == 0)
+          switch (magic[low]) {
             default: break;
             case 1: return file_magic::elf_relocatable;
             case 2: return file_magic::elf_executable;
diff --git a/lib/Support/PrettyStackTrace.cpp b/lib/Support/PrettyStackTrace.cpp
index 21d56adb5e..23ee5ab105 100644
--- a/lib/Support/PrettyStackTrace.cpp
+++ b/lib/Support/PrettyStackTrace.cpp
@@ -17,6 +17,7 @@
 #include "llvm/Config/config.h"     // Get autoconf configuration settings
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/ThreadLocal.h"
+#include "llvm/Support/Watchdog.h"
 #include "llvm/Support/raw_ostream.h"
 
 #ifdef HAVE_CRASHREPORTERCLIENT_H
@@ -37,7 +38,10 @@ static unsigned PrintStack(const PrettyStackTraceEntry *Entry, raw_ostream &OS){
   if (Entry->getNextEntry())
     NextID = PrintStack(Entry->getNextEntry(), OS);
   OS << NextID << ".\t";
-  Entry->print(OS);
+  {
+    sys::Watchdog W(5);
+    Entry->print(OS);
+  }
   
   return NextID+1;
 }
diff --git a/lib/Support/Program.cpp b/lib/Support/Program.cpp
index 75bc282d9b..201d5c0d30 100644
--- a/lib/Support/Program.cpp
+++ b/lib/Support/Program.cpp
@@ -29,12 +29,15 @@ Program::ExecuteAndWait(const Path& path,
                         const Path** redirects,
                         unsigned secondsToWait,
                         unsigned memoryLimit,
-                        std::string* ErrMsg) {
+                        std::string* ErrMsg,
+                        bool *ExecutionFailed) {
   Program prg;
-  if (prg.Execute(path, args, envp, redirects, memoryLimit, ErrMsg))
+  if (prg.Execute(path, args, envp, redirects, memoryLimit, ErrMsg)) {
+    if (ExecutionFailed) *ExecutionFailed = false;
     return prg.Wait(path, secondsToWait, ErrMsg);
-  else
-    return -1;
+  }
+  if (ExecutionFailed) *ExecutionFailed = true;
+  return -1;
 }
 
 void
diff --git a/lib/Support/SmallPtrSet.cpp b/lib/Support/SmallPtrSet.cpp
index 3b53e9ff49..f0fed7792c 100644
--- a/lib/Support/SmallPtrSet.cpp
+++ b/lib/Support/SmallPtrSet.cpp
@@ -29,13 +29,9 @@ void SmallPtrSetImpl::shrink_and_clear() {
   NumElements = NumTombstones = 0;
 
   // Install the new array.  Clear all the buckets to empty.
-  CurArray = (const void**)malloc(sizeof(void*) * (CurArraySize+1));
+  CurArray = (const void**)malloc(sizeof(void*) * CurArraySize);
   assert(CurArray && "Failed to allocate memory?");
   memset(CurArray, -1, CurArraySize*sizeof(void*));
-  
-  // The end pointer, always valid, is set to a valid element to help the
-  // iterator.
-  CurArray[CurArraySize] = 0;
 }
 
 bool SmallPtrSetImpl::insert_imp(const void * Ptr) {
@@ -139,15 +135,11 @@ void SmallPtrSetImpl::Grow(unsigned NewSize) {
   bool WasSmall = isSmall();
   
   // Install the new array.  Clear all the buckets to empty.
-  CurArray = (const void**)malloc(sizeof(void*) * (NewSize+1));
+  CurArray = (const void**)malloc(sizeof(void*) * NewSize);
   assert(CurArray && "Failed to allocate memory?");
   CurArraySize = NewSize;
   memset(CurArray, -1, NewSize*sizeof(void*));
   
-  // The end pointer, always valid, is set to a valid element to help the
-  // iterator.
-  CurArray[NewSize] = 0;
-  
   // Copy over all the elements.
   if (WasSmall) {
     // Small sets store their elements in order.
@@ -180,7 +172,7 @@ SmallPtrSetImpl::SmallPtrSetImpl(const void **SmallStorage,
     CurArray = SmallArray;
   // Otherwise, allocate new heap space (unless we were the same size)
   } else {
-    CurArray = (const void**)malloc(sizeof(void*) * (that.CurArraySize+1));
+    CurArray = (const void**)malloc(sizeof(void*) * that.CurArraySize);
     assert(CurArray && "Failed to allocate memory?");
   }
   
@@ -188,7 +180,7 @@ SmallPtrSetImpl::SmallPtrSetImpl(const void **SmallStorage,
   CurArraySize = that.CurArraySize;
 
   // Copy over the contents from the other set
-  memcpy(CurArray, that.CurArray, sizeof(void*)*(CurArraySize+1));
+  memcpy(CurArray, that.CurArray, sizeof(void*)*CurArraySize);
   
   NumElements = that.NumElements;
   NumTombstones = that.NumTombstones;
@@ -200,7 +192,7 @@ void SmallPtrSetImpl::CopyFrom(const SmallPtrSetImpl &RHS) {
   if (isSmall() && RHS.isSmall())
     assert(CurArraySize == RHS.CurArraySize &&
            "Cannot assign sets with different small sizes");
-           
+
   // If we're becoming small, prepare to insert into our stack space
   if (RHS.isSmall()) {
     if (!isSmall())
@@ -209,9 +201,9 @@ void SmallPtrSetImpl::CopyFrom(const SmallPtrSetImpl &RHS) {
   // Otherwise, allocate new heap space (unless we were the same size)
   } else if (CurArraySize != RHS.CurArraySize) {
     if (isSmall())
-      CurArray = (const void**)malloc(sizeof(void*) * (RHS.CurArraySize+1));
+      CurArray = (const void**)malloc(sizeof(void*) * RHS.CurArraySize);
     else
-      CurArray = (const void**)realloc(CurArray, sizeof(void*)*(RHS.CurArraySize+1));
+      CurArray = (const void**)realloc(CurArray, sizeof(void*)*RHS.CurArraySize);
     assert(CurArray && "Failed to allocate memory?");
   }
   
@@ -219,7 +211,7 @@ void SmallPtrSetImpl::CopyFrom(const SmallPtrSetImpl &RHS) {
   CurArraySize = RHS.CurArraySize;
 
   // Copy over the contents from the other set
-  memcpy(CurArray, RHS.CurArray, sizeof(void*)*(CurArraySize+1));
+  memcpy(CurArray, RHS.CurArray, sizeof(void*)*CurArraySize);
   
   NumElements = RHS.NumElements;
   NumTombstones = RHS.NumTombstones;
diff --git a/lib/Support/Statistic.cpp b/lib/Support/Statistic.cpp
index 3a6522101d..9c28176b73 100644
--- a/lib/Support/Statistic.cpp
+++ b/lib/Support/Statistic.cpp
@@ -40,7 +40,9 @@ namespace llvm { extern raw_ostream *CreateInfoOutputFile(); }
 /// what they did.
 ///
 static cl::opt<bool>
-Enabled("stats", cl::desc("Enable statistics output from program"));
+Enabled(
+    "stats",
+    cl::desc("Enable statistics output from program (available with Asserts)"));
 
 
 namespace {
@@ -142,6 +144,7 @@ void llvm::PrintStatistics(raw_ostream &OS) {
 }
 
 void llvm::PrintStatistics() {
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_STATS)
   StatisticInfo &Stats = *StatInfo;
 
   // Statistics not enabled?
@@ -151,4 +154,17 @@ void llvm::PrintStatistics() {
   raw_ostream &OutStream = *CreateInfoOutputFile();
   PrintStatistics(OutStream);
   delete &OutStream;   // Close the file.
+#else
+  // Check if the -stats option is set instead of checking
+  // !Stats.Stats.empty().  In release builds, Statistics operators
+  // do nothing, so stats are never Registered.
+  if (Enabled) {
+    // Get the stream to write to.
+    raw_ostream &OutStream = *CreateInfoOutputFile();
+    OutStream << "Statistics are disabled.  "
+            << "Build with asserts or with -DLLVM_ENABLE_STATS\n";
+    OutStream.flush();
+    delete &OutStream;   // Close the file.
+  }
+#endif
 }
diff --git a/lib/Support/Triple.cpp b/lib/Support/Triple.cpp
index d2508ac1ef..412e34ccc5 100644
--- a/lib/Support/Triple.cpp
+++ b/lib/Support/Triple.cpp
@@ -32,6 +32,7 @@ const char *Triple::getArchTypeName(ArchType Kind) {
   case r600:    return "r600";
   case sparc:   return "sparc";
   case sparcv9: return "sparcv9";
+  case systemz: return "s390x";
   case tce:     return "tce";
   case thumb:   return "thumb";
   case x86:     return "i386";
@@ -76,6 +77,8 @@ const char *Triple::getArchTypePrefix(ArchType Kind) {
   case sparcv9:
   case sparc:   return "sparc";
 
+  case systemz: return "systemz";
+
   case x86:
   case x86_64:  return "x86";
 
@@ -170,6 +173,7 @@ Triple::ArchType Triple::getArchTypeForLLVMName(StringRef Name) {
     .Case("hexagon", hexagon)
     .Case("sparc", sparc)
     .Case("sparcv9", sparcv9)
+    .Case("systemz", systemz)
     .Case("tce", tce)
     .Case("thumb", thumb)
     .Case("x86", x86)
@@ -233,6 +237,7 @@ static Triple::ArchType parseArch(StringRef ArchName) {
     .Case("mips64el", Triple::mips64el)
     .Case("r600", Triple::r600)
     .Case("hexagon", Triple::hexagon)
+    .Case("s390x", Triple::systemz)
     .Case("sparc", Triple::sparc)
     .Case("sparcv9", Triple::sparcv9)
     .Case("tce", Triple::tce)
@@ -687,6 +692,7 @@ static unsigned getArchPointerBitWidth(llvm::Triple::ArchType Arch) {
   case llvm::Triple::nvptx64:
   case llvm::Triple::ppc64:
   case llvm::Triple::sparcv9:
+  case llvm::Triple::systemz:
   case llvm::Triple::x86_64:
   case llvm::Triple::spir64:
     return 64;
@@ -712,6 +718,7 @@ Triple Triple::get32BitArchVariant() const {
   case Triple::UnknownArch:
   case Triple::aarch64:
   case Triple::msp430:
+  case Triple::systemz:
     T.setArch(UnknownArch);
     break;
 
@@ -769,6 +776,7 @@ Triple Triple::get64BitArchVariant() const {
   case Triple::nvptx64:
   case Triple::ppc64:
   case Triple::sparcv9:
+  case Triple::systemz:
   case Triple::x86_64:
     // Already 64-bit.
     break;
diff --git a/lib/Support/Unix/Memory.inc b/lib/Support/Unix/Memory.inc
index e6fba6801c..6be3ee045f 100644
--- a/lib/Support/Unix/Memory.inc
+++ b/lib/Support/Unix/Memory.inc
@@ -329,14 +329,23 @@ void Memory::InvalidateInstructionCache(const void *Addr,
   for (intptr_t Line = StartLine; Line < EndLine; Line += LineSize)
     asm volatile("icbi 0, %0" : : "r"(Line));
   asm volatile("isync");
-#  elif defined(__arm__) && defined(__GNUC__)
+#  elif (defined(__arm__) || defined(__aarch64__)) && defined(__GNUC__)
   // FIXME: Can we safely always call this for __GNUC__ everywhere?
   const char *Start = static_cast<const char *>(Addr);
   const char *End = Start + Len;
   __clear_cache(const_cast<char *>(Start), const_cast<char *>(End));
 #  elif defined(__mips__)
   const char *Start = static_cast<const char *>(Addr);
+#    if defined(ANDROID)
+  // The declaration of "cacheflush" in Android bionic:
+  // extern int cacheflush(long start, long end, long flags);
+  const char *End = Start + Len;
+  long LStart = reinterpret_cast<long>(const_cast<char *>(Start));
+  long LEnd = reinterpret_cast<long>(const_cast<char *>(End));
+  cacheflush(LStart, LEnd, BCACHE);
+#    else
   cacheflush(const_cast<char *>(Start), Len, BCACHE);
+#    endif
 #  endif
 
 #endif  // end apple
diff --git a/lib/Support/Unix/PathV2.inc b/lib/Support/Unix/PathV2.inc
index 4e77f1a82b..f426fbf7fc 100644
--- a/lib/Support/Unix/PathV2.inc
+++ b/lib/Support/Unix/PathV2.inc
@@ -260,6 +260,7 @@ error_code remove(const Twine &path, bool &existed) {
     existed = false;
   } else
     existed = true;
+
   return error_code::success();
 #endif
 }
@@ -416,9 +417,6 @@ error_code permissions(const Twine &path, perms prms) {
 error_code unique_file(const Twine &model, int &result_fd,
                        SmallVectorImpl<char> &result_path,
                        bool makeAbsolute, unsigned mode) {
-#ifdef __native_client__
-  llvm_unreachable("unique_file() not implemented for Native Client");
-#else
   SmallString<128> Model;
   model.toVector(Model);
   // Null terminate.
@@ -459,9 +457,7 @@ rety_open_create:
     if (SavedErrno == errc::file_exists)
       goto retry_random_path;
     // If path prefix doesn't exist, try to create it.
-    if (SavedErrno == errc::no_such_file_or_directory &&
-        !exists(path::parent_path(RandomPath)) &&
-        !TriedToCreateParent) {
+    if (SavedErrno == errc::no_such_file_or_directory && !TriedToCreateParent) {
       TriedToCreateParent = true;
       StringRef p(RandomPath);
       SmallString<64> dir_to_create;
@@ -502,19 +498,20 @@ rety_open_create:
 
   result_fd = RandomFD;
   return error_code::success();
-#endif
 }
 
-error_code mapped_file_region::init(int fd, uint64_t offset) {
+error_code mapped_file_region::init(int FD, bool CloseFD, uint64_t Offset) {
 #ifdef __native_client__
   // Newlib does not have ftruncate.
   llvm_unreachable("mapped_file_region not implemented for native client");
 #else
-  AutoFD FD(fd);
+  AutoFD ScopedFD(FD);
+  if (!CloseFD)
+    ScopedFD.take();
 
   // Figure out how large the file is.
   struct stat FileInfo;
-  if (fstat(fd, &FileInfo) == -1)
+  if (fstat(FD, &FileInfo) == -1)
     return error_code(errno, system_category());
   uint64_t FileSize = FileInfo.st_size;
 
@@ -522,7 +519,7 @@ error_code mapped_file_region::init(int fd, uint64_t offset) {
     Size = FileSize;
   else if (FileSize < Size) {
     // We need to grow the file.
-    if (ftruncate(fd, Size) == -1)
+    if (ftruncate(FD, Size) == -1)
       return error_code(errno, system_category());
   }
 
@@ -531,7 +528,7 @@ error_code mapped_file_region::init(int fd, uint64_t offset) {
 #ifdef MAP_FILE
   flags |= MAP_FILE;
 #endif
-  Mapping = ::mmap(0, Size, prot, flags, fd, offset);
+  Mapping = ::mmap(0, Size, prot, flags, FD, Offset);
   if (Mapping == MAP_FAILED)
     return error_code(errno, system_category());
   return error_code::success();
@@ -564,12 +561,13 @@ mapped_file_region::mapped_file_region(const Twine &path,
     return;
   }
 
-  ec = init(ofd, offset);
+  ec = init(ofd, true, offset);
   if (ec)
     Mapping = 0;
 }
 
 mapped_file_region::mapped_file_region(int fd,
+                                       bool closefd,
                                        mapmode mode,
                                        uint64_t length,
                                        uint64_t offset,
@@ -586,7 +584,7 @@ mapped_file_region::mapped_file_region(int fd,
     return;
   }
 
-  ec = init(fd, offset);
+  ec = init(fd, closefd, offset);
   if (ec)
     Mapping = 0;
 }
diff --git a/lib/Support/Unix/Program.inc b/lib/Support/Unix/Program.inc
index 834b1cc5dc..c6cc698e9b 100644
--- a/lib/Support/Unix/Program.inc
+++ b/lib/Support/Unix/Program.inc
@@ -32,6 +32,9 @@
 #if HAVE_FCNTL_H
 #include <fcntl.h>
 #endif
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
 #ifdef HAVE_POSIX_SPAWN
 #include <spawn.h>
 #if !defined(__APPLE__)
@@ -431,4 +434,25 @@ error_code Program::ChangeStderrToBinary(){
   return make_error_code(errc::success);
 }
 
+bool llvm::sys::argumentsFitWithinSystemLimits(ArrayRef<const char*> Args) {
+  static long ArgMax = sysconf(_SC_ARG_MAX);
+
+  // System says no practical limit.
+  if (ArgMax == -1)
+    return true;
+
+  // Conservatively account for space required by environment variables.
+  ArgMax /= 2;
+
+  size_t ArgLength = 0;
+  for (ArrayRef<const char*>::iterator I = Args.begin(), E = Args.end();
+       I != E; ++I) {
+    ArgLength += strlen(*I) + 1;
+    if (ArgLength > size_t(ArgMax)) {
+      return false;
+    }
+  }
+  return true;
+}
+
 }
diff --git a/lib/Support/Unix/Signals.inc b/lib/Support/Unix/Signals.inc
index d6fe7861bb..cdb1be900b 100644
--- a/lib/Support/Unix/Signals.inc
+++ b/lib/Support/Unix/Signals.inc
@@ -27,10 +27,12 @@
 #if HAVE_SYS_STAT_H
 #include <sys/stat.h>
 #endif
-#if HAVE_DLFCN_H && __GNUG__
-#include <dlfcn.h>
+#if HAVE_CXXABI_H
 #include <cxxabi.h>
 #endif
+#if HAVE_DLFCN_H
+#include <dlfcn.h>
+#endif
 #if HAVE_MACH_MACH_H
 #include <mach/mach.h>
 #endif
@@ -190,6 +192,15 @@ static RETSIGTYPE SignalHandler(int Sig) {
   // Otherwise if it is a fault (like SEGV) run any handler.
   for (unsigned i = 0, e = CallBacksToRun.size(); i != e; ++i)
     CallBacksToRun[i].first(CallBacksToRun[i].second);
+
+#ifdef __s390__
+  // On S/390, certain signals are delivered with PSW Address pointing to
+  // *after* the faulting instruction.  Simply returning from the signal
+  // handler would continue execution after that point, instead of
+  // re-raising the signal.  Raise the signal manually in those cases.
+  if (Sig == SIGILL || Sig == SIGFPE || Sig == SIGTRAP)
+    raise(Sig);
+#endif
 }
 
 void llvm::sys::RunInterruptHandlers() {
@@ -296,9 +307,13 @@ void llvm::sys::PrintStackTrace(FILE *FD) {
             (int)(sizeof(void*) * 2) + 2, (unsigned long)StackTrace[i]);
 
     if (dlinfo.dli_sname != NULL) {
-      int res;
       fputc(' ', FD);
+#  if HAVE_CXXABI_H
+      int res;
       char* d = abi::__cxa_demangle(dlinfo.dli_sname, NULL, NULL, &res);
+#  else
+      char* d = NULL;
+#  endif
       if (d == NULL) fputs(dlinfo.dli_sname, FD);
       else           fputs(d, FD);
       free(d);
diff --git a/lib/Support/Unix/Watchdog.inc b/lib/Support/Unix/Watchdog.inc
new file mode 100644
index 0000000000..5d89c0e51b
--- /dev/null
+++ b/lib/Support/Unix/Watchdog.inc
@@ -0,0 +1,32 @@
+//===--- Unix/Watchdog.inc - Unix Watchdog Implementation -------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides the generic Unix implementation of the Watchdog class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+namespace llvm {
+  namespace sys {
+    Watchdog::Watchdog(unsigned int seconds) {
+#ifdef HAVE_UNISTD_H
+      alarm(seconds);
+#endif
+    }
+
+    Watchdog::~Watchdog() {
+#ifdef HAVE_UNISTD_H
+      alarm(0);
+#endif
+    }
+  }
+}
diff --git a/lib/Support/Watchdog.cpp b/lib/Support/Watchdog.cpp
new file mode 100644
index 0000000000..724aa001f1
--- /dev/null
+++ b/lib/Support/Watchdog.cpp
@@ -0,0 +1,23 @@
+//===---- Watchdog.cpp - Implement Watchdog ---------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file implements the Watchdog class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/Watchdog.h"
+#include "llvm/Config/config.h"
+
+// Include the platform-specific parts of this class.
+#ifdef LLVM_ON_UNIX
+#include "Unix/Watchdog.inc"
+#endif
+#ifdef LLVM_ON_WIN32
+#include "Windows/Watchdog.inc"
+#endif
diff --git a/lib/Support/Windows/PathV2.inc b/lib/Support/Windows/PathV2.inc
index 2e6cc96e7f..23f3d14f91 100644
--- a/lib/Support/Windows/PathV2.inc
+++ b/lib/Support/Windows/PathV2.inc
@@ -593,6 +593,10 @@ retry_random_path:
   random_path_utf16.push_back(0);
   random_path_utf16.pop_back();
 
+  // Make sure we don't fall into an infinite loop by constantly trying
+  // to create the parent path.
+  bool TriedToCreateParent = false;
+
   // Try to create + open the path.
 retry_create_file:
   HANDLE TempFileHandle = ::CreateFileW(random_path_utf16.begin(),
@@ -610,7 +614,9 @@ retry_create_file:
     if (ec == windows_error::file_exists)
       goto retry_random_path;
     // Check for non-existing parent directories.
-    if (ec == windows_error::path_not_found) {
+    if (ec == windows_error::path_not_found && !TriedToCreateParent) {
+      TriedToCreateParent = true;
+
       // Create the directories using result_path as temp storage.
       if (error_code ec = UTF16ToUTF8(random_path_utf16.begin(),
                                       random_path_utf16.size(), result_path))
@@ -705,13 +711,14 @@ error_code get_magic(const Twine &path, uint32_t len,
   return error_code::success();
 }
 
-error_code mapped_file_region::init(int FD, uint64_t Offset) {
+error_code mapped_file_region::init(int FD, bool CloseFD, uint64_t Offset) {
   FileDescriptor = FD;
   // Make sure that the requested size fits within SIZE_T.
   if (Size > std::numeric_limits<SIZE_T>::max()) {
-    if (FileDescriptor)
-      _close(FileDescriptor);
-    else
+    if (FileDescriptor) {
+      if (CloseFD)
+        _close(FileDescriptor);
+    } else
       ::CloseHandle(FileHandle);
     return make_error_code(errc::invalid_argument);
   }
@@ -732,9 +739,10 @@ error_code mapped_file_region::init(int FD, uint64_t Offset) {
                                           0);
   if (FileMappingHandle == NULL) {
     error_code ec = windows_error(GetLastError());
-    if (FileDescriptor)
-      _close(FileDescriptor);
-    else
+    if (FileDescriptor) {
+      if (CloseFD)
+        _close(FileDescriptor);
+    } else
       ::CloseHandle(FileHandle);
     return ec;
   }
@@ -754,9 +762,10 @@ error_code mapped_file_region::init(int FD, uint64_t Offset) {
   if (Mapping == NULL) {
     error_code ec = windows_error(GetLastError());
     ::CloseHandle(FileMappingHandle);
-    if (FileDescriptor)
-      _close(FileDescriptor);
-    else
+    if (FileDescriptor) {
+      if (CloseFD)
+        _close(FileDescriptor);
+    } else
       ::CloseHandle(FileHandle);
     return ec;
   }
@@ -768,14 +777,24 @@ error_code mapped_file_region::init(int FD, uint64_t Offset) {
       error_code ec = windows_error(GetLastError());
       ::UnmapViewOfFile(Mapping);
       ::CloseHandle(FileMappingHandle);
-      if (FileDescriptor)
-        _close(FileDescriptor);
-      else
+      if (FileDescriptor) {
+        if (CloseFD)
+          _close(FileDescriptor);
+      } else
         ::CloseHandle(FileHandle);
       return ec;
     }
     Size = mbi.RegionSize;
   }
+
+  // Close all the handles except for the view. It will keep the other handles
+  // alive.
+  ::CloseHandle(FileMappingHandle);
+  if (FileDescriptor) {
+    if (CloseFD)
+      _close(FileDescriptor); // Also closes FileHandle.
+  } else
+    ::CloseHandle(FileHandle);
   return error_code::success();
 }
 
@@ -815,7 +834,7 @@ mapped_file_region::mapped_file_region(const Twine &path,
   }
 
   FileDescriptor = 0;
-  ec = init(FileDescriptor, offset);
+  ec = init(FileDescriptor, true, offset);
   if (ec) {
     Mapping = FileMappingHandle = 0;
     FileHandle = INVALID_HANDLE_VALUE;
@@ -824,6 +843,7 @@ mapped_file_region::mapped_file_region(const Twine &path,
 }
 
 mapped_file_region::mapped_file_region(int fd,
+                                       bool closefd,
                                        mapmode mode,
                                        uint64_t length,
                                        uint64_t offset,
@@ -836,13 +856,14 @@ mapped_file_region::mapped_file_region(int fd,
   , FileMappingHandle() {
   FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(fd));
   if (FileHandle == INVALID_HANDLE_VALUE) {
-    _close(FileDescriptor);
+    if (closefd)
+      _close(FileDescriptor);
     FileDescriptor = 0;
     ec = make_error_code(errc::bad_file_descriptor);
     return;
   }
 
-  ec = init(FileDescriptor, offset);
+  ec = init(FileDescriptor, closefd, offset);
   if (ec) {
     Mapping = FileMappingHandle = 0;
     FileHandle = INVALID_HANDLE_VALUE;
@@ -853,12 +874,6 @@ mapped_file_region::mapped_file_region(int fd,
 mapped_file_region::~mapped_file_region() {
   if (Mapping)
     ::UnmapViewOfFile(Mapping);
-  if (FileMappingHandle)
-    ::CloseHandle(FileMappingHandle);
-  if (FileDescriptor)
-    _close(FileDescriptor);
-  else if (FileHandle != INVALID_HANDLE_VALUE)
-    ::CloseHandle(FileHandle);
 }
 
 #if LLVM_HAS_RVALUE_REFERENCES
diff --git a/lib/Support/Windows/Program.inc b/lib/Support/Windows/Program.inc
index 691d6d4555..619ae5d8f7 100644
--- a/lib/Support/Windows/Program.inc
+++ b/lib/Support/Windows/Program.inc
@@ -126,20 +126,58 @@ static bool ArgNeedsQuotes(const char *Str) {
   return Str[0] == '\0' || strpbrk(Str, "\t \"&\'()*<>\\`^|") != 0;
 }
 
+/// CountPrecedingBackslashes - Returns the number of backslashes preceding Cur
+/// in the C string Start.
+static unsigned int CountPrecedingBackslashes(const char *Start,
+                                              const char *Cur) {
+  unsigned int Count = 0;
+  --Cur;
+  while (Cur >= Start && *Cur == '\\') {
+    ++Count;
+    --Cur;
+  }
+  return Count;
+}
+
+/// EscapePrecedingEscapes - Append a backslash to Dst for every backslash
+/// preceding Cur in the Start string.  Assumes Dst has enough space.
+static char *EscapePrecedingEscapes(char *Dst, const char *Start,
+                                    const char *Cur) {
+  unsigned PrecedingEscapes = CountPrecedingBackslashes(Start, Cur);
+  while (PrecedingEscapes > 0) {
+    *Dst++ = '\\';
+    --PrecedingEscapes;
+  }
+  return Dst;
+}
 
 /// ArgLenWithQuotes - Check whether argument needs to be quoted when calling
 /// CreateProcess and returns length of quoted arg with escaped quotes
 static unsigned int ArgLenWithQuotes(const char *Str) {
-  unsigned int len = ArgNeedsQuotes(Str) ? 2 : 0;
+  const char *Start = Str;
+  bool Quoted = ArgNeedsQuotes(Str);
+  unsigned int len = Quoted ? 2 : 0;
 
   while (*Str != '\0') {
-    if (*Str == '\"')
-      ++len;
+    if (*Str == '\"') {
+      // We need to add a backslash, but ensure that it isn't escaped.
+      unsigned PrecedingEscapes = CountPrecedingBackslashes(Start, Str);
+      len += PrecedingEscapes + 1;
+    }
+    // Note that we *don't* need to escape runs of backslashes that don't
+    // precede a double quote!  See MSDN:
+    // http://msdn.microsoft.com/en-us/library/17w5ykft%28v=vs.85%29.aspx
 
     ++len;
     ++Str;
   }
 
+  if (Quoted) {
+    // Make sure the closing quote doesn't get escaped by a trailing backslash.
+    unsigned PrecedingEscapes = CountPrecedingBackslashes(Start, Str);
+    len += PrecedingEscapes + 1;
+  }
+
   return len;
 }
 
@@ -180,20 +218,27 @@ Program::Execute(const Path& path,
 
   for (unsigned i = 0; args[i]; i++) {
     const char *arg = args[i];
+    const char *start = arg;
 
     bool needsQuoting = ArgNeedsQuotes(arg);
     if (needsQuoting)
       *p++ = '"';
 
     while (*arg != '\0') {
-      if (*arg == '\"')
+      if (*arg == '\"') {
+        // Escape all preceding escapes (if any), and then escape the quote.
+        p = EscapePrecedingEscapes(p, start, arg);
         *p++ = '\\';
+      }
 
       *p++ = *arg++;
     }
 
-    if (needsQuoting)
+    if (needsQuoting) {
+      // Make sure our quote doesn't get escaped by a trailing backslash.
+      p = EscapePrecedingEscapes(p, start, arg);
       *p++ = '"';
+    }
     *p++ = ' ';
   }
 
@@ -396,4 +441,20 @@ error_code Program::ChangeStderrToBinary(){
   return make_error_code(errc::success);
 }
 
+bool llvm::sys::argumentsFitWithinSystemLimits(ArrayRef<const char*> Args) {
+  // The documented max length of the command line passed to CreateProcess.
+  static const size_t MaxCommandStringLength = 32768;
+  size_t ArgLength = 0;
+  for (ArrayRef<const char*>::iterator I = Args.begin(), E = Args.end();
+       I != E; ++I) {
+    // Account for the trailing space for every arg but the last one and the
+    // trailing NULL of the last argument.
+    ArgLength += ArgLenWithQuotes(*I) + 1;
+    if (ArgLength > MaxCommandStringLength) {
+      return false;
+    }
+  }
+  return true;
+}
+
 }
diff --git a/lib/Support/Windows/Signals.inc b/lib/Support/Windows/Signals.inc
index 3dd6660b03..b18b4d1dac 100644
--- a/lib/Support/Windows/Signals.inc
+++ b/lib/Support/Windows/Signals.inc
@@ -178,6 +178,19 @@ namespace llvm {
 //===----------------------------------------------------------------------===//
 
 #ifdef _MSC_VER
+/// AvoidMessageBoxHook - Emulates hitting "retry" from an "abort, retry,
+/// ignore" CRT debug report dialog.  "retry" raises an exception which
+/// ultimately triggers our stack dumper.
+static int AvoidMessageBoxHook(int ReportType, char *Message, int *Return) {
+  // Set *Return to the retry code for the return value of _CrtDbgReport:
+  // http://msdn.microsoft.com/en-us/library/8hyw4sy7(v=vs.71).aspx
+  // This may also trigger just-in-time debugging via DebugBreak().
+  if (Return)
+    *Return = 1;
+  // Don't call _CrtDbgReport.
+  return TRUE;
+}
+
 /// CRTReportHook - Function called on a CRT debugging event.
 static int CRTReportHook(int ReportType, char *Message, int *Return) {
   // Don't cause a DebugBreak() on return.
@@ -238,6 +251,15 @@ static void RegisterHandler() {
   OldFilter = SetUnhandledExceptionFilter(LLVMUnhandledExceptionFilter);
   SetConsoleCtrlHandler(LLVMConsoleCtrlHandler, TRUE);
 
+#ifdef _MSC_VER
+  const char *EnableMsgbox = getenv("LLVM_ENABLE_CRT_REPORT");
+  if (!EnableMsgbox || strcmp("0", EnableMsgbox) == 0) {
+    // Setting a report hook overrides the default behavior of popping an "abort,
+    // retry, or ignore" dialog.
+    _CrtSetReportHook(AvoidMessageBoxHook);
+  }
+#endif
+
   // Environment variable to disable any kind of crash dialog.
   if (getenv("LLVM_DISABLE_CRASH_REPORT")) {
 #ifdef _MSC_VER
diff --git a/lib/Support/Windows/Watchdog.inc b/lib/Support/Windows/Watchdog.inc
new file mode 100644
index 0000000000..fab2bdf2a9
--- /dev/null
+++ b/lib/Support/Windows/Watchdog.inc
@@ -0,0 +1,24 @@
+//===--- Windows/Watchdog.inc - Windows Watchdog Implementation -*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides the generic Windows implementation of the Watchdog class.
+//
+//===----------------------------------------------------------------------===//
+
+// TODO: implement.
+// Currently this is only used by PrettyStackTrace which is also unimplemented
+// on Windows. Roughly, a Windows implementation would use CreateWaitableTimer
+// and a second thread to run the TimerAPCProc.
+
+namespace llvm {
+  namespace sys {
+    Watchdog::Watchdog(unsigned int seconds) {}
+    Watchdog::~Watchdog() {}
+  }
+}
diff --git a/lib/Support/YAMLParser.cpp b/lib/Support/YAMLParser.cpp
index 2cead20c0b..213f5e1568 100644
--- a/lib/Support/YAMLParser.cpp
+++ b/lib/Support/YAMLParser.cpp
@@ -260,7 +260,7 @@ public:
   Token getNext();
 
   void printError(SMLoc Loc, SourceMgr::DiagKind Kind, const Twine &Message,
-                  ArrayRef<SMRange> Ranges = ArrayRef<SMRange>()) {
+                  ArrayRef<SMRange> Ranges = None) {
     SM.PrintMessage(Loc, Kind, Message, Ranges);
   }
 
diff --git a/lib/Support/raw_ostream.cpp b/lib/Support/raw_ostream.cpp
index f71abd3b24..a433088b19 100644
--- a/lib/Support/raw_ostream.cpp
+++ b/lib/Support/raw_ostream.cpp
@@ -306,7 +306,12 @@ raw_ostream &raw_ostream::write(const char *Ptr, size_t Size) {
     if (LLVM_UNLIKELY(OutBufCur == OutBufStart)) {
       size_t BytesToWrite = Size - (Size % NumBytes);
       write_impl(Ptr, BytesToWrite);
-      copy_to_buffer(Ptr + BytesToWrite, Size - BytesToWrite);
+      size_t BytesRemaining = Size - BytesToWrite;
+      if (BytesRemaining > size_t(OutBufEnd - OutBufCur)) {
+        // Too much left over to copy into our buffer.
+        return write(Ptr + BytesToWrite, BytesRemaining);
+      }
+      copy_to_buffer(Ptr + BytesToWrite, BytesRemaining);
       return *this;
     }
 
@@ -512,7 +517,7 @@ raw_fd_ostream::~raw_fd_ostream() {
   // has_error() and clear the error flag with clear_error() before
   // destructing raw_ostream objects which may have errors.
   if (has_error())
-    report_fatal_error("IO failure on output stream.");
+    report_fatal_error("IO failure on output stream.", /*GenCrashDiag=*/false);
 }