vendor/llvm/llvm-trunk-r306325

15 files changed, 207 insertions, 114 deletions

diff --git a/lib/Support/APFloat.cpp b/lib/Support/APFloat.cpp
index f36c25a0ce91..deb76cb565d1 100644
--- a/lib/Support/APFloat.cpp
+++ b/lib/Support/APFloat.cpp
@@ -37,10 +37,6 @@
 
 using namespace llvm;
 
-// TODO: Remove these and use APInt qualified types directly.
-typedef APInt::WordType integerPart;
-const unsigned int integerPartWidth = APInt::APINT_BITS_PER_WORD;
-
 /// A macro used to combine two fcCategory enums into one key which can be used
 /// in a switch statement to classify how the interaction of two APFloat's
 /// categories affects an operation.
@@ -51,7 +47,7 @@ const unsigned int integerPartWidth = APInt::APINT_BITS_PER_WORD;
 
 /* Assumed in hexadecimal significand parsing, and conversion to
    hexadecimal strings.  */
-static_assert(integerPartWidth % 4 == 0, "Part width must be divisible by 4!");
+static_assert(APFloatBase::integerPartWidth % 4 == 0, "Part width must be divisible by 4!");
 
 namespace llvm {
   /* Represents floating point arithmetic semantics.  */
@@ -153,8 +149,7 @@ namespace llvm {
   const unsigned int maxExponent = 16383;
   const unsigned int maxPrecision = 113;
   const unsigned int maxPowerOfFiveExponent = maxExponent + maxPrecision - 1;
-  const unsigned int maxPowerOfFiveParts = 2 + ((maxPowerOfFiveExponent * 815)
-                                                / (351 * integerPartWidth));
+  const unsigned int maxPowerOfFiveParts = 2 + ((maxPowerOfFiveExponent * 815) / (351 * APFloatBase::integerPartWidth));
 
   unsigned int APFloatBase::semanticsPrecision(const fltSemantics &semantics) {
     return semantics.precision;
@@ -180,7 +175,7 @@ namespace llvm {
 static inline unsigned int
 partCountForBits(unsigned int bits)
 {
-  return ((bits) + integerPartWidth - 1) / integerPartWidth;
+  return ((bits) + APFloatBase::integerPartWidth - 1) / APFloatBase::integerPartWidth;
 }
 
 /* Returns 0U-9U.  Return values >= 10U are not digits.  */
@@ -420,7 +415,7 @@ trailingHexadecimalFraction(StringRef::iterator p, StringRef::iterator end,
 /* Return the fraction lost were a bignum truncated losing the least
    significant BITS bits.  */
 static lostFraction
-lostFractionThroughTruncation(const integerPart *parts,
+lostFractionThroughTruncation(const APFloatBase::integerPart *parts,
                               unsigned int partCount,
                               unsigned int bits)
 {
@@ -433,7 +428,7 @@ lostFractionThroughTruncation(const integerPart *parts,
     return lfExactlyZero;
   if (bits == lsb + 1)
     return lfExactlyHalf;
-  if (bits <= partCount * integerPartWidth &&
+  if (bits <= partCount * APFloatBase::integerPartWidth &&
       APInt::tcExtractBit(parts, bits - 1))
     return lfMoreThanHalf;
 
@@ -442,7 +437,7 @@ lostFractionThroughTruncation(const integerPart *parts,
 
 /* Shift DST right BITS bits noting lost fraction.  */
 static lostFraction
-shiftRight(integerPart *dst, unsigned int parts, unsigned int bits)
+shiftRight(APFloatBase::integerPart *dst, unsigned int parts, unsigned int bits)
 {
   lostFraction lost_fraction;
 
@@ -489,22 +484,22 @@ HUerrBound(bool inexactMultiply, unsigned int HUerr1, unsigned int HUerr2)
 /* The number of ulps from the boundary (zero, or half if ISNEAREST)
    when the least significant BITS are truncated.  BITS cannot be
    zero.  */
-static integerPart
-ulpsFromBoundary(const integerPart *parts, unsigned int bits, bool isNearest)
-{
+static APFloatBase::integerPart
+ulpsFromBoundary(const APFloatBase::integerPart *parts, unsigned int bits,
+                 bool isNearest) {
   unsigned int count, partBits;
-  integerPart part, boundary;
+  APFloatBase::integerPart part, boundary;
 
   assert(bits != 0);
 
   bits--;
-  count = bits / integerPartWidth;
-  partBits = bits % integerPartWidth + 1;
+  count = bits / APFloatBase::integerPartWidth;
+  partBits = bits % APFloatBase::integerPartWidth + 1;
 
-  part = parts[count] & (~(integerPart) 0 >> (integerPartWidth - partBits));
+  part = parts[count] & (~(APFloatBase::integerPart) 0 >> (APFloatBase::integerPartWidth - partBits));
 
   if (isNearest)
-    boundary = (integerPart) 1 << (partBits - 1);
+    boundary = (APFloatBase::integerPart) 1 << (partBits - 1);
   else
     boundary = 0;
 
@@ -518,32 +513,30 @@ ulpsFromBoundary(const integerPart *parts, unsigned int bits, bool isNearest)
   if (part == boundary) {
     while (--count)
       if (parts[count])
-        return ~(integerPart) 0; /* A lot.  */
+        return ~(APFloatBase::integerPart) 0; /* A lot.  */
 
     return parts[0];
   } else if (part == boundary - 1) {
     while (--count)
       if (~parts[count])
-        return ~(integerPart) 0; /* A lot.  */
+        return ~(APFloatBase::integerPart) 0; /* A lot.  */
 
     return -parts[0];
   }
 
-  return ~(integerPart) 0; /* A lot.  */
+  return ~(APFloatBase::integerPart) 0; /* A lot.  */
 }
 
 /* Place pow(5, power) in DST, and return the number of parts used.
    DST must be at least one part larger than size of the answer.  */
 static unsigned int
-powerOf5(integerPart *dst, unsigned int power)
-{
-  static const integerPart firstEightPowers[] = { 1, 5, 25, 125, 625, 3125,
-                                                  15625, 78125 };
-  integerPart pow5s[maxPowerOfFiveParts * 2 + 5];
+powerOf5(APFloatBase::integerPart *dst, unsigned int power) {
+  static const APFloatBase::integerPart firstEightPowers[] = { 1, 5, 25, 125, 625, 3125, 15625, 78125 };
+  APFloatBase::integerPart pow5s[maxPowerOfFiveParts * 2 + 5];
   pow5s[0] = 78125 * 5;
 
   unsigned int partsCount[16] = { 1 };
-  integerPart scratch[maxPowerOfFiveParts], *p1, *p2, *pow5;
+  APFloatBase::integerPart scratch[maxPowerOfFiveParts], *p1, *p2, *pow5;
   unsigned int result;
   assert(power <= maxExponent);
 
@@ -572,7 +565,7 @@ powerOf5(integerPart *dst, unsigned int power)
     }
 
     if (power & 1) {
-      integerPart *tmp;
+      APFloatBase::integerPart *tmp;
 
       APInt::tcFullMultiply(p2, p1, pow5, result, pc);
       result += pc;
@@ -608,14 +601,14 @@ static const char NaNU[] = "NAN";
    significant nibble.  Write out exactly COUNT hexdigits, return
    COUNT.  */
 static unsigned int
-partAsHex (char *dst, integerPart part, unsigned int count,
+partAsHex (char *dst, APFloatBase::integerPart part, unsigned int count,
            const char *hexDigitChars)
 {
   unsigned int result = count;
 
-  assert(count != 0 && count <= integerPartWidth / 4);
+  assert(count != 0 && count <= APFloatBase::integerPartWidth / 4);
 
-  part >>= (integerPartWidth - 4 * count);
+  part >>= (APFloatBase::integerPartWidth - 4 * count);
   while (count--) {
     dst[count] = hexDigitChars[part & 0xf];
     part >>= 4;
@@ -889,11 +882,11 @@ unsigned int IEEEFloat::partCount() const {
   return partCountForBits(semantics->precision + 1);
 }
 
-const integerPart *IEEEFloat::significandParts() const {
+const IEEEFloat::integerPart *IEEEFloat::significandParts() const {
   return const_cast<IEEEFloat *>(this)->significandParts();
 }
 
-integerPart *IEEEFloat::significandParts() {
+IEEEFloat::integerPart *IEEEFloat::significandParts() {
   if (partCount() > 1)
     return significand.parts;
   else
@@ -916,7 +909,7 @@ void IEEEFloat::incrementSignificand() {
 }
 
 /* Add the significand of the RHS.  Returns the carry flag.  */
-integerPart IEEEFloat::addSignificand(const IEEEFloat &rhs) {
+IEEEFloat::integerPart IEEEFloat::addSignificand(const IEEEFloat &rhs) {
   integerPart *parts;
 
   parts = significandParts();
@@ -929,8 +922,8 @@ integerPart IEEEFloat::addSignificand(const IEEEFloat &rhs) {
 
 /* Subtract the significand of the RHS with a borrow flag.  Returns
    the borrow flag.  */
-integerPart IEEEFloat::subtractSignificand(const IEEEFloat &rhs,
-                                           integerPart borrow) {
+IEEEFloat::integerPart IEEEFloat::subtractSignificand(const IEEEFloat &rhs,
+                                                      integerPart borrow) {
   integerPart *parts;
 
   parts = significandParts();
diff --git a/lib/Support/APInt.cpp b/lib/Support/APInt.cpp
index e9716e3b1e87..c558ddd82161 100644
--- a/lib/Support/APInt.cpp
+++ b/lib/Support/APInt.cpp
@@ -546,10 +546,7 @@ unsigned APInt::countLeadingZerosSlowCase() const {
   return Count;
 }
 
-unsigned APInt::countLeadingOnes() const {
-  if (isSingleWord())
-    return llvm::countLeadingOnes(U.VAL << (APINT_BITS_PER_WORD - BitWidth));
-
+unsigned APInt::countLeadingOnesSlowCase() const {
   unsigned highWordBits = BitWidth % APINT_BITS_PER_WORD;
   unsigned shift;
   if (!highWordBits) {
@@ -573,9 +570,7 @@ unsigned APInt::countLeadingOnes() const {
   return Count;
 }
 
-unsigned APInt::countTrailingZeros() const {
-  if (isSingleWord())
-    return std::min(unsigned(llvm::countTrailingZeros(U.VAL)), BitWidth);
+unsigned APInt::countTrailingZerosSlowCase() const {
   unsigned Count = 0;
   unsigned i = 0;
   for (; i < getNumWords() && U.pVal[i] == 0; ++i)
diff --git a/lib/Support/BinaryStreamReader.cpp b/lib/Support/BinaryStreamReader.cpp
index bfb658cfa0b7..e00527f2519e 100644
--- a/lib/Support/BinaryStreamReader.cpp
+++ b/lib/Support/BinaryStreamReader.cpp
@@ -109,6 +109,12 @@ Error BinaryStreamReader::readStreamRef(BinaryStreamRef &Ref, uint32_t Length) {
   return Error::success();
 }
 
+Error BinaryStreamReader::readSubstream(BinarySubstreamRef &Stream,
+                                        uint32_t Size) {
+  Stream.Offset = getOffset();
+  return readStreamRef(Stream.StreamData, Size);
+}
+
 Error BinaryStreamReader::skip(uint32_t Amount) {
   if (Amount > bytesRemaining())
     return make_error<BinaryStreamError>(stream_error_code::stream_too_short);
diff --git a/lib/Support/CachePruning.cpp b/lib/Support/CachePruning.cpp
index aca123639565..60d0964f2764 100644
--- a/lib/Support/CachePruning.cpp
+++ b/lib/Support/CachePruning.cpp
@@ -82,7 +82,7 @@ llvm::parseCachePruningPolicy(StringRef PolicyStr) {
       if (Value.back() != '%')
         return make_error<StringError>("'" + Value + "' must be a percentage",
                                        inconvertibleErrorCode());
-      StringRef SizeStr = Value.slice(0, Value.size() - 1);
+      StringRef SizeStr = Value.drop_back();
       uint64_t Size;
       if (SizeStr.getAsInteger(0, Size))
         return make_error<StringError>("'" + SizeStr + "' not an integer",
@@ -91,7 +91,28 @@ llvm::parseCachePruningPolicy(StringRef PolicyStr) {
         return make_error<StringError>("'" + SizeStr +
                                            "' must be between 0 and 100",
                                        inconvertibleErrorCode());
-      Policy.PercentageOfAvailableSpace = Size;
+      Policy.MaxSizePercentageOfAvailableSpace = Size;
+    } else if (Key == "cache_size_bytes") {
+      uint64_t Mult = 1;
+      switch (tolower(Value.back())) {
+      case 'k':
+        Mult = 1024;
+        Value = Value.drop_back();
+        break;
+      case 'm':
+        Mult = 1024 * 1024;
+        Value = Value.drop_back();
+        break;
+      case 'g':
+        Mult = 1024 * 1024 * 1024;
+        Value = Value.drop_back();
+        break;
+      }
+      uint64_t Size;
+      if (Value.getAsInteger(0, Size))
+        return make_error<StringError>("'" + Value + "' not an integer",
+                                       inconvertibleErrorCode());
+      Policy.MaxSizeBytes = Size * Mult;
     } else {
       return make_error<StringError>("Unknown key: '" + Key + "'",
                                      inconvertibleErrorCode());
@@ -115,11 +136,12 @@ bool llvm::pruneCache(StringRef Path, CachePruningPolicy Policy) {
   if (!isPathDir)
     return false;
 
-  Policy.PercentageOfAvailableSpace =
-      std::min(Policy.PercentageOfAvailableSpace, 100u);
+  Policy.MaxSizePercentageOfAvailableSpace =
+      std::min(Policy.MaxSizePercentageOfAvailableSpace, 100u);
 
   if (Policy.Expiration == seconds(0) &&
-      Policy.PercentageOfAvailableSpace == 0) {
+      Policy.MaxSizePercentageOfAvailableSpace == 0 &&
+      Policy.MaxSizeBytes == 0) {
     DEBUG(dbgs() << "No pruning settings set, exit early\n");
     // Nothing will be pruned, early exit
     return false;
@@ -157,7 +179,8 @@ bool llvm::pruneCache(StringRef Path, CachePruningPolicy Policy) {
     writeTimestampFile(TimestampFile);
   }
 
-  bool ShouldComputeSize = (Policy.PercentageOfAvailableSpace > 0);
+  bool ShouldComputeSize =
+      (Policy.MaxSizePercentageOfAvailableSpace > 0 || Policy.MaxSizeBytes > 0);
 
   // Keep track of space
   std::set<std::pair<uint64_t, std::string>> FileSizes;
@@ -216,14 +239,22 @@ bool llvm::pruneCache(StringRef Path, CachePruningPolicy Policy) {
     }
     sys::fs::space_info SpaceInfo = ErrOrSpaceInfo.get();
     auto AvailableSpace = TotalSize + SpaceInfo.free;
-    auto FileAndSize = FileSizes.rbegin();
+
+    if (Policy.MaxSizePercentageOfAvailableSpace == 0)
+      Policy.MaxSizePercentageOfAvailableSpace = 100;
+    if (Policy.MaxSizeBytes == 0)
+      Policy.MaxSizeBytes = AvailableSpace;
+    auto TotalSizeTarget = std::min<uint64_t>(
+        AvailableSpace * Policy.MaxSizePercentageOfAvailableSpace / 100ull,
+        Policy.MaxSizeBytes);
+
     DEBUG(dbgs() << "Occupancy: " << ((100 * TotalSize) / AvailableSpace)
-                 << "% target is: " << Policy.PercentageOfAvailableSpace
-                 << "\n");
+                 << "% target is: " << Policy.MaxSizePercentageOfAvailableSpace
+                 << "%, " << Policy.MaxSizeBytes << " bytes\n");
+
+    auto FileAndSize = FileSizes.rbegin();
     // Remove the oldest accessed files first, till we get below the threshold
-    while (((100 * TotalSize) / AvailableSpace) >
-               Policy.PercentageOfAvailableSpace &&
-           FileAndSize != FileSizes.rend()) {
+    while (TotalSize > TotalSizeTarget && FileAndSize != FileSizes.rend()) {
       // Remove the file.
       sys::fs::remove(FileAndSize->second);
       // Update size
diff --git a/lib/Support/CommandLine.cpp b/lib/Support/CommandLine.cpp
index de0ca940b405..0345a5e3d2a1 100644
--- a/lib/Support/CommandLine.cpp
+++ b/lib/Support/CommandLine.cpp
@@ -24,6 +24,7 @@
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/Config/config.h"
@@ -1522,13 +1523,9 @@ bool parser<unsigned long long>::parse(Option &O, StringRef ArgName,
 // parser<double>/parser<float> implementation
 //
 static bool parseDouble(Option &O, StringRef Arg, double &Value) {
-  SmallString<32> TmpStr(Arg.begin(), Arg.end());
-  const char *ArgStart = TmpStr.c_str();
-  char *End;
-  Value = strtod(ArgStart, &End);
-  if (*End != 0)
-    return O.error("'" + Arg + "' value invalid for floating point argument!");
-  return false;
+  if (to_float(Arg, Value))
+    return false;
+  return O.error("'" + Arg + "' value invalid for floating point argument!");
 }
 
 bool parser<double>::parse(Option &O, StringRef ArgName, StringRef Arg,
diff --git a/lib/Support/DataExtractor.cpp b/lib/Support/DataExtractor.cpp
index 53c10bcc562e..0199b300ba72 100644
--- a/lib/Support/DataExtractor.cpp
+++ b/lib/Support/DataExtractor.cpp
@@ -68,6 +68,13 @@ uint16_t *DataExtractor::getU16(uint32_t *offset_ptr, uint16_t *dst,
                         Data.data());
 }
 
+uint32_t DataExtractor::getU24(uint32_t *offset_ptr) const {
+  uint24_t ExtractedVal =
+      getU<uint24_t>(offset_ptr, this, IsLittleEndian, Data.data());
+  // The 3 bytes are in the correct byte order for the host.
+  return ExtractedVal.getAsUint32(sys::IsLittleEndianHost);
+}
+
 uint32_t DataExtractor::getU32(uint32_t *offset_ptr) const {
   return getU<uint32_t>(offset_ptr, this, IsLittleEndian, Data.data());
 }
diff --git a/lib/Support/GraphWriter.cpp b/lib/Support/GraphWriter.cpp
index f70b77da8de4..e04bd8bb3b9a 100644
--- a/lib/Support/GraphWriter.cpp
+++ b/lib/Support/GraphWriter.cpp
@@ -1,4 +1,4 @@
-//===-- GraphWriter.cpp - Implements GraphWriter support routines ---------===//
+//===- GraphWriter.cpp - Implements GraphWriter support routines ----------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -12,10 +12,22 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Support/GraphWriter.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringRef.h"
 #include "llvm/Config/config.h"
 #include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/ErrorOr.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Program.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cassert>
+#include <system_error>
+#include <string>
+#include <vector>
+
 using namespace llvm;
 
 static cl::opt<bool> ViewBackground("view-background", cl::Hidden,
@@ -99,8 +111,10 @@ static bool ExecGraphViewer(StringRef ExecPath, std::vector<const char *> &args,
 }
 
 namespace {
+
 struct GraphSession {
   std::string LogBuffer;
+
   bool TryFindProgram(StringRef Names, std::string &ProgramPath) {
     raw_string_ostream Log(LogBuffer);
     SmallVector<StringRef, 8> parts;
@@ -115,7 +129,8 @@ struct GraphSession {
     return false;
   }
 };
-} // namespace
+
+} // end anonymous namespace
 
 static const char *getProgramName(GraphProgram::Name program) {
   switch (program) {
diff --git a/lib/Support/Triple.cpp b/lib/Support/Triple.cpp
index 320aede79fbb..2687a67556d3 100644
--- a/lib/Support/Triple.cpp
+++ b/lib/Support/Triple.cpp
@@ -174,6 +174,7 @@ StringRef Triple::getOSTypeName(OSType Kind) {
   switch (Kind) {
   case UnknownOS: return "unknown";
 
+  case Ananas: return "ananas";
   case CloudABI: return "cloudabi";
   case Darwin: return "darwin";
   case DragonFly: return "dragonfly";
@@ -455,6 +456,7 @@ static Triple::VendorType parseVendor(StringRef VendorName) {
 
 static Triple::OSType parseOS(StringRef OSName) {
   return StringSwitch<Triple::OSType>(OSName)
+    .StartsWith("ananas", Triple::Ananas)
     .StartsWith("cloudabi", Triple::CloudABI)
     .StartsWith("darwin", Triple::Darwin)
     .StartsWith("dragonfly", Triple::DragonFly)
diff --git a/lib/Support/Unix/Host.inc b/lib/Support/Unix/Host.inc
index 457217125a22..0ba6a25aa198 100644
--- a/lib/Support/Unix/Host.inc
+++ b/lib/Support/Unix/Host.inc
@@ -45,5 +45,11 @@ std::string sys::getDefaultTargetTriple() {
     TargetTripleString += getOSVersion();
   }
 
+  // Override the default target with an environment variable named by LLVM_TARGET_TRIPLE_ENV.
+#if defined(LLVM_TARGET_TRIPLE_ENV)
+  if (const char *EnvTriple = std::getenv(LLVM_TARGET_TRIPLE_ENV))
+    TargetTripleString = EnvTriple;
+#endif
+
   return Triple::normalize(TargetTripleString);
 }
diff --git a/lib/Support/Unix/Memory.inc b/lib/Support/Unix/Memory.inc
index edbc7938f0cb..dd39ef935bf9 100644
--- a/lib/Support/Unix/Memory.inc
+++ b/lib/Support/Unix/Memory.inc
@@ -195,6 +195,10 @@ Memory::AllocateRWX(size_t NumBytes, const MemoryBlock* NearBlock,
 #if defined(__APPLE__) && (defined(__arm__) || defined(__arm64__))
   void *pa = ::mmap(start, PageSize*NumPages, PROT_READ|PROT_EXEC,
                     flags, fd, 0);
+#elif defined(__NetBSD__) && defined(PROT_MPROTECT)
+  void *pa =
+      ::mmap(start, PageSize * NumPages,
+             PROT_READ | PROT_WRITE | PROT_MPROTECT(PROT_EXEC), flags, fd, 0);
 #else
   void *pa = ::mmap(start, PageSize*NumPages, PROT_READ|PROT_WRITE|PROT_EXEC,
                     flags, fd, 0);
diff --git a/lib/Support/Unix/Program.inc b/lib/Support/Unix/Program.inc
index 2df0eaff47e5..1704fa479942 100644
--- a/lib/Support/Unix/Program.inc
+++ b/lib/Support/Unix/Program.inc
@@ -449,11 +449,22 @@ bool llvm::sys::commandLineFitsWithinSystemLimits(StringRef Program, ArrayRef<co
   size_t ArgLength = Program.size() + 1;
   for (ArrayRef<const char*>::iterator I = Args.begin(), E = Args.end();
        I != E; ++I) {
-    ArgLength += strlen(*I) + 1;
+    size_t length = strlen(*I);
+
+    // Ensure that we do not exceed the MAX_ARG_STRLEN constant on Linux, which
+    // does not have a constant unlike what the man pages would have you
+    // believe. Since this limit is pretty high, perform the check
+    // unconditionally rather than trying to be aggressive and limiting it to
+    // Linux only.
+    if (length >= (32 * 4096))
+      return false;
+
+    ArgLength += length + 1;
     if (ArgLength > size_t(HalfArgMax)) {
       return false;
     }
   }
+
   return true;
 }
 }
diff --git a/lib/Support/Windows/Host.inc b/lib/Support/Windows/Host.inc
index fe89fe0aad8c..7e196cf0ce18 100644
--- a/lib/Support/Windows/Host.inc
+++ b/lib/Support/Windows/Host.inc
@@ -18,5 +18,13 @@
 using namespace llvm;
 
 std::string sys::getDefaultTargetTriple() {
-  return Triple::normalize(LLVM_DEFAULT_TARGET_TRIPLE);
+  const char *Triple = LLVM_DEFAULT_TARGET_TRIPLE;
+
+  // Override the default target with an environment variable named by LLVM_TARGET_TRIPLE_ENV.
+#if defined(LLVM_TARGET_TRIPLE_ENV)
+  if (const char *EnvTriple = std::getenv(LLVM_TARGET_TRIPLE_ENV))
+    Triple = EnvTriple;
+#endif
+
+  return Triple::normalize(Triple);
 }
diff --git a/lib/Support/YAMLParser.cpp b/lib/Support/YAMLParser.cpp
index 01ae3214453d..e2f21a56a810 100644
--- a/lib/Support/YAMLParser.cpp
+++ b/lib/Support/YAMLParser.cpp
@@ -1,4 +1,4 @@
-//===--- YAMLParser.cpp - Simple YAML parser ------------------------------===//
+//===- YAMLParser.cpp - Simple YAML parser --------------------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -13,15 +13,29 @@
 
 #include "llvm/Support/YAMLParser.h"
 #include "llvm/ADT/AllocatorList.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/None.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/Twine.h"
+#include "llvm/Support/Compiler.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/SMLoc.h"
 #include "llvm/Support/SourceMgr.h"
 #include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+#include <map>
+#include <memory>
+#include <string>
+#include <system_error>
+#include <utility>
 
 using namespace llvm;
 using namespace yaml;
@@ -37,7 +51,7 @@ enum UnicodeEncodingForm {
 
 /// EncodingInfo - Holds the encoding type and length of the byte order mark if
 ///                it exists. Length is in {0, 2, 3, 4}.
-typedef std::pair<UnicodeEncodingForm, unsigned> EncodingInfo;
+using EncodingInfo = std::pair<UnicodeEncodingForm, unsigned>;
 
 /// getUnicodeEncoding - Reads up to the first 4 bytes to determine the Unicode
 ///                      encoding form of \a Input.
@@ -46,7 +60,7 @@ typedef std::pair<UnicodeEncodingForm, unsigned> EncodingInfo;
 /// @returns An EncodingInfo indicating the Unicode encoding form of the input
 ///          and how long the byte order mark is if one exists.
 static EncodingInfo getUnicodeEncoding(StringRef Input) {
-  if (Input.size() == 0)
+  if (Input.empty())
     return std::make_pair(UEF_Unknown, 0);
 
   switch (uint8_t(Input[0])) {
@@ -95,8 +109,6 @@ static EncodingInfo getUnicodeEncoding(StringRef Input) {
   return std::make_pair(UEF_UTF8, 0);
 }
 
-namespace llvm {
-namespace yaml {
 /// Pin the vtables to this file.
 void Node::anchor() {}
 void NullNode::anchor() {}
@@ -107,6 +119,9 @@ void MappingNode::anchor() {}
 void SequenceNode::anchor() {}
 void AliasNode::anchor() {}
 
+namespace llvm {
+namespace yaml {
+
 /// Token - A single YAML token.
 struct Token {
   enum TokenKind {
@@ -133,7 +148,7 @@ struct Token {
     TK_Alias,
     TK_Anchor,
     TK_Tag
-  } Kind;
+  } Kind = TK_Error;
 
   /// A string of length 0 or more whose begin() points to the logical location
   /// of the token in the input.
@@ -142,14 +157,16 @@ struct Token {
   /// The value of a block scalar node.
   std::string Value;
 
-  Token() : Kind(TK_Error) {}
+  Token() = default;
 };
-}
-}
 
-typedef llvm::BumpPtrList<Token> TokenQueueT;
+} // end namespace yaml
+} // end namespace llvm
+
+using TokenQueueT = BumpPtrList<Token>;
 
 namespace {
+
 /// @brief This struct is used to track simple keys.
 ///
 /// Simple keys are handled by creating an entry in SimpleKeys for each Token
@@ -170,12 +187,13 @@ struct SimpleKey {
     return Tok == Other.Tok;
   }
 };
-}
+
+} // end anonymous namespace
 
 /// @brief The Unicode scalar value of a UTF-8 minimal well-formed code unit
 ///        subsequence and the subsequence's length in code units (uint8_t).
 ///        A length of 0 represents an error.
-typedef std::pair<uint32_t, unsigned> UTF8Decoded;
+using UTF8Decoded = std::pair<uint32_t, unsigned>;
 
 static UTF8Decoded decodeUTF8(StringRef Range) {
   StringRef::iterator Position= Range.begin();
@@ -229,6 +247,7 @@ static UTF8Decoded decodeUTF8(StringRef Range) {
 
 namespace llvm {
 namespace yaml {
+
 /// @brief Scans YAML tokens from a MemoryBuffer.
 class Scanner {
 public:
@@ -350,7 +369,8 @@ private:
   ///          ns-char.
   StringRef::iterator skip_ns_char(StringRef::iterator Position);
 
-  typedef StringRef::iterator (Scanner::*SkipWhileFunc)(StringRef::iterator);
+  using SkipWhileFunc = StringRef::iterator (Scanner::*)(StringRef::iterator);
+
   /// @brief Skip minimal well-formed code unit subsequences until Func
   ///        returns its input.
   ///
@@ -655,10 +675,10 @@ bool yaml::dumpTokens(StringRef Input, raw_ostream &OS) {
 }
 
 bool yaml::scanTokens(StringRef Input) {
-  llvm::SourceMgr SM;
-  llvm::yaml::Scanner scanner(Input, SM);
-  for (;;) {
-    llvm::yaml::Token T = scanner.getNext();
+  SourceMgr SM;
+  Scanner scanner(Input, SM);
+  while (true) {
+    Token T = scanner.getNext();
     if (T.Kind == Token::TK_StreamEnd)
       break;
     else if (T.Kind == Token::TK_Error)
@@ -1744,7 +1764,7 @@ Stream::Stream(MemoryBufferRef InputBuffer, SourceMgr &SM, bool ShowColors,
                std::error_code *EC)
     : scanner(new Scanner(InputBuffer, SM, ShowColors, EC)), CurrentDoc() {}
 
-Stream::~Stream() {}
+Stream::~Stream() = default;
 
 bool Stream::failed() { return scanner->failed(); }
 
@@ -1851,8 +1871,6 @@ bool Node::failed() const {
   return Doc->failed();
 }
 
-
-
 StringRef ScalarNode::getValue(SmallVectorImpl<char> &Storage) const {
   // TODO: Handle newlines properly. We need to remove leading whitespace.
   if (Value[0] == '"') { // Double quoted.
diff --git a/lib/Support/YAMLTraits.cpp b/lib/Support/YAMLTraits.cpp
index c410b1d56086..601084f9eae3 100644
--- a/lib/Support/YAMLTraits.cpp
+++ b/lib/Support/YAMLTraits.cpp
@@ -8,17 +8,27 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Support/YAMLTraits.h"
+#include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/Errc.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/LineIterator.h"
+#include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/YAMLParser.h"
 #include "llvm/Support/raw_ostream.h"
-#include <cctype>
+#include <algorithm>
+#include <cassert>
+#include <cstdint>
+#include <cstdlib>
 #include <cstring>
+#include <string>
+#include <vector>
+
 using namespace llvm;
 using namespace yaml;
 
@@ -26,11 +36,9 @@ using namespace yaml;
 //  IO
 //===----------------------------------------------------------------------===//
 
-IO::IO(void *Context) : Ctxt(Context) {
-}
+IO::IO(void *Context) : Ctxt(Context) {}
 
-IO::~IO() {
-}
+IO::~IO() = default;
 
 void *IO::getContext() {
   return Ctxt;
@@ -46,15 +54,13 @@ void IO::setContext(void *Context) {
 
 Input::Input(StringRef InputContent, void *Ctxt,
              SourceMgr::DiagHandlerTy DiagHandler, void *DiagHandlerCtxt)
-    : IO(Ctxt), Strm(new Stream(InputContent, SrcMgr, false, &EC)),
-      CurrentNode(nullptr) {
+    : IO(Ctxt), Strm(new Stream(InputContent, SrcMgr, false, &EC)) {
   if (DiagHandler)
     SrcMgr.setDiagHandler(DiagHandler, DiagHandlerCtxt);
   DocIterator = Strm->begin();
 }
 
-Input::~Input() {
-}
+Input::~Input() = default;
 
 std::error_code Input::error() { return EC; }
 
@@ -398,13 +404,9 @@ bool Input::canElideEmptySequence() {
 //===----------------------------------------------------------------------===//
 
 Output::Output(raw_ostream &yout, void *context, int WrapColumn)
-    : IO(context), Out(yout), WrapColumn(WrapColumn), Column(0),
-      ColumnAtFlowStart(0), ColumnAtMapFlowStart(0), NeedBitValueComma(false),
-      NeedFlowSequenceComma(false), EnumerationMatchFound(false),
-      NeedsNewLine(false), WriteDefaultValues(false) {}
+    : IO(context), Out(yout), WrapColumn(WrapColumn) {}
 
-Output::~Output() {
-}
+Output::~Output() = default;
 
 bool Output::outputting() {
   return true;
@@ -911,12 +913,9 @@ void ScalarTraits<double>::output(const double &Val, void *, raw_ostream &Out) {
 }
 
 StringRef ScalarTraits<double>::input(StringRef Scalar, void *, double &Val) {
-  SmallString<32> buff(Scalar.begin(), Scalar.end());
-  char *end;
-  Val = strtod(buff.c_str(), &end);
-  if (*end != '\0')
-    return "invalid floating point number";
-  return StringRef();
+  if (to_float(Scalar, Val))
+    return StringRef();
+  return "invalid floating point number";
 }
 
 void ScalarTraits<float>::output(const float &Val, void *, raw_ostream &Out) {
@@ -924,12 +923,9 @@ void ScalarTraits<float>::output(const float &Val, void *, raw_ostream &Out) {
 }
 
 StringRef ScalarTraits<float>::input(StringRef Scalar, void *, float &Val) {
-  SmallString<32> buff(Scalar.begin(), Scalar.end());
-  char *end;
-  Val = strtod(buff.c_str(), &end);
-  if (*end != '\0')
-    return "invalid floating point number";
-  return StringRef();
+  if (to_float(Scalar, Val))
+    return StringRef();
+  return "invalid floating point number";
 }
 
 void ScalarTraits<Hex8>::output(const Hex8 &Val, void *, raw_ostream &Out) {
diff --git a/lib/Support/raw_ostream.cpp b/lib/Support/raw_ostream.cpp
index 1abc8ed8683d..9480cd46d28f 100644
--- a/lib/Support/raw_ostream.cpp
+++ b/lib/Support/raw_ostream.cpp
@@ -548,7 +548,11 @@ void raw_fd_ostream::write_impl(const char *Ptr, size_t Size) {
   pos += Size;
 
 #ifndef LLVM_ON_WIN32
+#if defined(__linux__)
+  bool ShouldWriteInChunks = true;
+#else
   bool ShouldWriteInChunks = false;
+#endif
 #else
   // Writing a large size of output to Windows console returns ENOMEM. It seems
   // that, prior to Windows 8, WriteFile() is redirecting to WriteConsole(), and