vendor/clang/clang-r142614

20 files changed, 1983 insertions, 750 deletions

diff --git a/lib/Lex/HeaderMap.cpp b/lib/Lex/HeaderMap.cpp
index e102a6da608c..0cb564c222d5 100644
--- a/lib/Lex/HeaderMap.cpp
+++ b/lib/Lex/HeaderMap.cpp
@@ -57,7 +57,7 @@ struct HMapHeader {
 /// HashHMapKey - This is the 'well known' hash function required by the file
 /// format, used to look up keys in the hash table.  The hash table uses simple
 /// linear probing based on this function.
-static inline unsigned HashHMapKey(llvm::StringRef Str) {
+static inline unsigned HashHMapKey(StringRef Str) {
   unsigned Result = 0;
   const char *S = Str.begin(), *End = Str.end();
 
@@ -200,7 +200,7 @@ void HeaderMap::dump() const {
 /// LookupFile - Check to see if the specified relative filename is located in
 /// this HeaderMap.  If so, open it and return its FileEntry.
 const FileEntry *HeaderMap::LookupFile(
-    llvm::StringRef Filename, FileManager &FM) const {
+    StringRef Filename, FileManager &FM) const {
   const HMapHeader &Hdr = getHeader();
   unsigned NumBuckets = getEndianAdjustedWord(Hdr.NumBuckets);
 
diff --git a/lib/Lex/HeaderSearch.cpp b/lib/Lex/HeaderSearch.cpp
index 86ab9564a235..931145a8d655 100644
--- a/lib/Lex/HeaderSearch.cpp
+++ b/lib/Lex/HeaderSearch.cpp
@@ -18,6 +18,7 @@
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
 #include "llvm/ADT/SmallString.h"
+#include "llvm/Support/Capacity.h"
 #include <cstdio>
 using namespace clang;
 
@@ -97,6 +98,60 @@ const HeaderMap *HeaderSearch::CreateHeaderMap(const FileEntry *FE) {
   return 0;
 }
 
+const FileEntry *HeaderSearch::lookupModule(StringRef ModuleName,
+                                            std::string *ModuleFileName,
+                                            std::string *UmbrellaHeader) {
+  // If we don't have a module cache path, we can't do anything.
+  if (ModuleCachePath.empty()) {
+    if (ModuleFileName)
+      ModuleFileName->clear();
+    return 0;
+  }
+  
+  // Try to find the module path.
+  llvm::SmallString<256> FileName(ModuleCachePath);
+  llvm::sys::path::append(FileName, ModuleName + ".pcm");
+  if (ModuleFileName)
+    *ModuleFileName = FileName.str();
+    
+  if (const FileEntry *ModuleFile
+        = getFileMgr().getFile(FileName, /*OpenFile=*/false,
+                               /*CacheFailure=*/false))
+    return ModuleFile;
+  
+  // We didn't find the module. If we're not supposed to look for an
+  // umbrella header, this is the end of the road.
+  if (!UmbrellaHeader)
+    return 0;
+  
+  // Look in each of the framework directories for an umbrella header with
+  // the same name as the module.
+  // FIXME: We need a way for non-frameworks to provide umbrella headers.
+  llvm::SmallString<128> UmbrellaHeaderName;
+  UmbrellaHeaderName = ModuleName;
+  UmbrellaHeaderName += '/';
+  UmbrellaHeaderName += ModuleName;
+  UmbrellaHeaderName += ".h";
+  for (unsigned Idx = 0, N = SearchDirs.size(); Idx != N; ++Idx) {
+    // Skip non-framework include paths
+    if (!SearchDirs[Idx].isFramework())
+      continue;
+    
+    // Look for the umbrella header in this directory.
+    if (const FileEntry *HeaderFile
+          = SearchDirs[Idx].LookupFile(UmbrellaHeaderName, *this, 0, 0, 
+                                       StringRef(), 0)) {
+      *UmbrellaHeader = HeaderFile->getName();
+      return 0;
+    }
+  }
+  
+  // We did not find an umbrella header. Clear out the UmbrellaHeader pointee
+  // so our caller knows that we failed.
+  UmbrellaHeader->clear();
+  return 0;
+}
+
 //===----------------------------------------------------------------------===//
 // File lookup within a DirectoryLookup scope
 //===----------------------------------------------------------------------===//
@@ -116,17 +171,19 @@ const char *DirectoryLookup::getName() const {
 /// LookupFile - Lookup the specified file in this search path, returning it
 /// if it exists or returning null if not.
 const FileEntry *DirectoryLookup::LookupFile(
-    llvm::StringRef Filename,
+    StringRef Filename,
     HeaderSearch &HS,
-    llvm::SmallVectorImpl<char> *SearchPath,
-    llvm::SmallVectorImpl<char> *RelativePath) const {
+    SmallVectorImpl<char> *SearchPath,
+    SmallVectorImpl<char> *RelativePath,
+    StringRef BuildingModule,
+    StringRef *SuggestedModule) const {
   llvm::SmallString<1024> TmpDir;
   if (isNormalDir()) {
     // Concatenate the requested file onto the directory.
     TmpDir = getDir()->getName();
     llvm::sys::path::append(TmpDir, Filename);
     if (SearchPath != NULL) {
-      llvm::StringRef SearchPathRef(getDir()->getName());
+      StringRef SearchPathRef(getDir()->getName());
       SearchPath->clear();
       SearchPath->append(SearchPathRef.begin(), SearchPathRef.end());
     }
@@ -138,14 +195,15 @@ const FileEntry *DirectoryLookup::LookupFile(
   }
 
   if (isFramework())
-    return DoFrameworkLookup(Filename, HS, SearchPath, RelativePath);
+    return DoFrameworkLookup(Filename, HS, SearchPath, RelativePath,
+                             BuildingModule, SuggestedModule);
 
   assert(isHeaderMap() && "Unknown directory lookup");
   const FileEntry * const Result = getHeaderMap()->LookupFile(
       Filename, HS.getFileMgr());
   if (Result) {
     if (SearchPath != NULL) {
-      llvm::StringRef SearchPathRef(getName());
+      StringRef SearchPathRef(getName());
       SearchPath->clear();
       SearchPath->append(SearchPathRef.begin(), SearchPathRef.end());
     }
@@ -161,15 +219,18 @@ const FileEntry *DirectoryLookup::LookupFile(
 /// DoFrameworkLookup - Do a lookup of the specified file in the current
 /// DirectoryLookup, which is a framework directory.
 const FileEntry *DirectoryLookup::DoFrameworkLookup(
-    llvm::StringRef Filename,
+    StringRef Filename,
     HeaderSearch &HS,
-    llvm::SmallVectorImpl<char> *SearchPath,
-    llvm::SmallVectorImpl<char> *RelativePath) const {
+    SmallVectorImpl<char> *SearchPath,
+    SmallVectorImpl<char> *RelativePath,
+    StringRef BuildingModule,
+    StringRef *SuggestedModule) const 
+{
   FileManager &FileMgr = HS.getFileMgr();
 
   // Framework names must have a '/' in the filename.
   size_t SlashPos = Filename.find('/');
-  if (SlashPos == llvm::StringRef::npos) return 0;
+  if (SlashPos == StringRef::npos) return 0;
 
   // Find out if this is the home for the specified framework, by checking
   // HeaderSearch.  Possible answer are yes/no and unknown.
@@ -226,9 +287,16 @@ const FileEntry *DirectoryLookup::DoFrameworkLookup(
     SearchPath->append(FrameworkName.begin(), FrameworkName.end()-1);
   }
 
+  /// Determine whether this is the module we're building or not.
+  bool AutomaticImport = SuggestedModule &&
+    (BuildingModule != StringRef(Filename.begin(), SlashPos)) &&
+    !Filename.substr(SlashPos + 1).startswith("..");
+  
   FrameworkName.append(Filename.begin()+SlashPos+1, Filename.end());
   if (const FileEntry *FE = FileMgr.getFile(FrameworkName.str(),
-                                            /*openFile=*/true)) {
+                                            /*openFile=*/!AutomaticImport)) {
+    if (AutomaticImport)
+      *SuggestedModule = StringRef(Filename.begin(), SlashPos);
     return FE;
   }
 
@@ -240,7 +308,11 @@ const FileEntry *DirectoryLookup::DoFrameworkLookup(
     SearchPath->insert(SearchPath->begin()+OrigSize, Private,
                        Private+strlen(Private));
 
-  return FileMgr.getFile(FrameworkName.str(), /*openFile=*/true);
+  const FileEntry *FE = FileMgr.getFile(FrameworkName.str(), 
+                                        /*openFile=*/!AutomaticImport);
+  if (FE && AutomaticImport)
+    *SuggestedModule = StringRef(Filename.begin(), SlashPos);
+  return FE;
 }
 
 
@@ -255,13 +327,18 @@ const FileEntry *DirectoryLookup::DoFrameworkLookup(
 /// non-null, indicates where the #including file is, in case a relative search
 /// is needed.
 const FileEntry *HeaderSearch::LookupFile(
-    llvm::StringRef Filename,
+    StringRef Filename,
     bool isAngled,
     const DirectoryLookup *FromDir,
     const DirectoryLookup *&CurDir,
     const FileEntry *CurFileEnt,
-    llvm::SmallVectorImpl<char> *SearchPath,
-    llvm::SmallVectorImpl<char> *RelativePath) {
+    SmallVectorImpl<char> *SearchPath,
+    SmallVectorImpl<char> *RelativePath,
+    StringRef *SuggestedModule) 
+{
+  if (SuggestedModule)
+    *SuggestedModule = StringRef();
+    
   // If 'Filename' is absolute, check to see if it exists and no searching.
   if (llvm::sys::path::is_absolute(Filename)) {
     CurDir = 0;
@@ -279,7 +356,7 @@ const FileEntry *HeaderSearch::LookupFile(
     return FileMgr.getFile(Filename, /*openFile=*/true);
   }
 
-  // Step #0, unless disabled, check to see if the file is in the #includer's
+  // Unless disabled, check to see if the file is in the #includer's
   // directory.  This has to be based on CurFileEnt, not CurDir, because
   // CurFileEnt could be a #include of a subdirectory (#include "foo/bar.h") and
   // a subsequent include of "baz.h" should resolve to "whatever/foo/baz.h".
@@ -301,7 +378,7 @@ const FileEntry *HeaderSearch::LookupFile(
       unsigned DirInfo = getFileInfo(CurFileEnt).DirInfo;
       getFileInfo(FE).DirInfo = DirInfo;
       if (SearchPath != NULL) {
-        llvm::StringRef SearchPathRef(CurFileEnt->getDir()->getName());
+        StringRef SearchPathRef(CurFileEnt->getDir()->getName());
         SearchPath->clear();
         SearchPath->append(SearchPathRef.begin(), SearchPathRef.end());
       }
@@ -346,19 +423,56 @@ const FileEntry *HeaderSearch::LookupFile(
   // Check each directory in sequence to see if it contains this file.
   for (; i != SearchDirs.size(); ++i) {
     const FileEntry *FE =
-      SearchDirs[i].LookupFile(Filename, *this, SearchPath, RelativePath);
+      SearchDirs[i].LookupFile(Filename, *this, SearchPath, RelativePath,
+                               BuildingModule, SuggestedModule);
     if (!FE) continue;
 
     CurDir = &SearchDirs[i];
 
     // This file is a system header or C++ unfriendly if the dir is.
-    getFileInfo(FE).DirInfo = CurDir->getDirCharacteristic();
-
+    HeaderFileInfo &HFI = getFileInfo(FE);
+    HFI.DirInfo = CurDir->getDirCharacteristic();
+
+    // If this file is found in a header map and uses the framework style of
+    // includes, then this header is part of a framework we're building.
+    if (CurDir->isIndexHeaderMap()) {
+      size_t SlashPos = Filename.find('/');
+      if (SlashPos != StringRef::npos) {
+        HFI.IndexHeaderMapHeader = 1;
+        HFI.Framework = getUniqueFrameworkName(StringRef(Filename.begin(), 
+                                                         SlashPos));
+      }
+    }
+    
     // Remember this location for the next lookup we do.
     CacheLookup.second = i;
     return FE;
   }
 
+  // If we are including a file with a quoted include "foo.h" from inside
+  // a header in a framework that is currently being built, and we couldn't
+  // resolve "foo.h" any other way, change the include to <Foo/foo.h>, where
+  // "Foo" is the name of the framework in which the including header was found.
+  if (CurFileEnt && !isAngled && Filename.find('/') == StringRef::npos) {
+    HeaderFileInfo &IncludingHFI = getFileInfo(CurFileEnt);
+    if (IncludingHFI.IndexHeaderMapHeader) {
+      llvm::SmallString<128> ScratchFilename;
+      ScratchFilename += IncludingHFI.Framework;
+      ScratchFilename += '/';
+      ScratchFilename += Filename;
+      
+      const FileEntry *Result = LookupFile(ScratchFilename, /*isAngled=*/true,
+                                           FromDir, CurDir, CurFileEnt, 
+                                           SearchPath, RelativePath,
+                                           SuggestedModule);
+      std::pair<unsigned, unsigned> &CacheLookup 
+        = LookupFileCache.GetOrCreateValue(Filename).getValue();
+      CacheLookup.second
+        = LookupFileCache.GetOrCreateValue(ScratchFilename).getValue().second;
+      return Result;
+    }
+  }
+
   // Otherwise, didn't find it. Remember we didn't find this.
   CacheLookup.second = SearchDirs.size();
   return 0;
@@ -370,15 +484,15 @@ const FileEntry *HeaderSearch::LookupFile(
 /// is a subframework within Carbon.framework.  If so, return the FileEntry
 /// for the designated file, otherwise return null.
 const FileEntry *HeaderSearch::
-LookupSubframeworkHeader(llvm::StringRef Filename,
+LookupSubframeworkHeader(StringRef Filename,
                          const FileEntry *ContextFileEnt,
-                         llvm::SmallVectorImpl<char> *SearchPath,
-                         llvm::SmallVectorImpl<char> *RelativePath) {
+                         SmallVectorImpl<char> *SearchPath,
+                         SmallVectorImpl<char> *RelativePath) {
   assert(ContextFileEnt && "No context file?");
 
   // Framework names must have a '/' in the filename.  Find it.
   size_t SlashPos = Filename.find('/');
-  if (SlashPos == llvm::StringRef::npos) return 0;
+  if (SlashPos == StringRef::npos) return 0;
 
   // Look up the base framework name of the ContextFileEnt.
   const char *ContextName = ContextFileEnt->getName();
@@ -466,7 +580,31 @@ LookupSubframeworkHeader(llvm::StringRef Filename,
 // File Info Management.
 //===----------------------------------------------------------------------===//
 
+/// \brief Merge the header file info provided by \p OtherHFI into the current
+/// header file info (\p HFI)
+static void mergeHeaderFileInfo(HeaderFileInfo &HFI, 
+                                const HeaderFileInfo &OtherHFI) {
+  HFI.isImport |= OtherHFI.isImport;
+  HFI.isPragmaOnce |= OtherHFI.isPragmaOnce;
+  HFI.NumIncludes += OtherHFI.NumIncludes;
+  
+  if (!HFI.ControllingMacro && !HFI.ControllingMacroID) {
+    HFI.ControllingMacro = OtherHFI.ControllingMacro;
+    HFI.ControllingMacroID = OtherHFI.ControllingMacroID;
+  }
+  
+  if (OtherHFI.External) {
+    HFI.DirInfo = OtherHFI.DirInfo;
+    HFI.External = OtherHFI.External;
+    HFI.IndexHeaderMapHeader = OtherHFI.IndexHeaderMapHeader;
+  }
 
+  if (HFI.Framework.empty())
+    HFI.Framework = OtherHFI.Framework;
+  
+  HFI.Resolved = true;
+}
+                                
 /// getFileInfo - Return the HeaderFileInfo structure for the specified
 /// FileEntry.
 HeaderFileInfo &HeaderSearch::getFileInfo(const FileEntry *FE) {
@@ -474,10 +612,8 @@ HeaderFileInfo &HeaderSearch::getFileInfo(const FileEntry *FE) {
     FileInfo.resize(FE->getUID()+1);
   
   HeaderFileInfo &HFI = FileInfo[FE->getUID()];
-  if (ExternalSource && !HFI.Resolved) {
-    HFI = ExternalSource->GetHeaderFileInfo(FE);
-    HFI.Resolved = true;
-  }
+  if (ExternalSource && !HFI.Resolved)
+    mergeHeaderFileInfo(HFI, ExternalSource->GetHeaderFileInfo(FE));
   return HFI;
 }
 
@@ -488,10 +624,8 @@ bool HeaderSearch::isFileMultipleIncludeGuarded(const FileEntry *File) {
 
   // Resolve header file info from the external source, if needed.
   HeaderFileInfo &HFI = FileInfo[File->getUID()];
-  if (ExternalSource && !HFI.Resolved) {
-    HFI = ExternalSource->GetHeaderFileInfo(File);
-    HFI.Resolved = true;
-  }
+  if (ExternalSource && !HFI.Resolved)
+    mergeHeaderFileInfo(HFI, ExternalSource->GetHeaderFileInfo(File));
 
   return HFI.isPragmaOnce || HFI.ControllingMacro || HFI.ControllingMacroID;
 }
@@ -542,4 +676,14 @@ bool HeaderSearch::ShouldEnterIncludeFile(const FileEntry *File, bool isImport){
   return true;
 }
 
+size_t HeaderSearch::getTotalMemory() const {
+  return SearchDirs.capacity()
+    + llvm::capacity_in_bytes(FileInfo)
+    + llvm::capacity_in_bytes(HeaderMaps)
+    + LookupFileCache.getAllocator().getTotalMemory()
+    + FrameworkMap.getAllocator().getTotalMemory();
+}
 
+StringRef HeaderSearch::getUniqueFrameworkName(StringRef Framework) {
+  return FrameworkNames.GetOrCreateValue(Framework).getKey();
+}
diff --git a/lib/Lex/Lexer.cpp b/lib/Lex/Lexer.cpp
index a28b8f6e7b9f..a98d889dbc98 100644
--- a/lib/Lex/Lexer.cpp
+++ b/lib/Lex/Lexer.cpp
@@ -32,7 +32,7 @@
 #include "llvm/ADT/StringSwitch.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/MemoryBuffer.h"
-#include <cctype>
+#include <cstring>
 using namespace clang;
 
 static void InitCharacterInfo();
@@ -76,7 +76,7 @@ void Lexer::InitLexer(const char *BufStart, const char *BufPtr,
   // skip the UTF-8 BOM if it's present.
   if (BufferStart == BufferPtr) {
     // Determine the size of the BOM.
-    llvm::StringRef Buf(BufferStart, BufferEnd - BufferStart);
+    StringRef Buf(BufferStart, BufferEnd - BufferStart);
     size_t BOMLength = llvm::StringSwitch<size_t>(Buf)
       .StartsWith("\xEF\xBB\xBF", 3) // UTF-8 BOM
       .Default(0);
@@ -86,7 +86,7 @@ void Lexer::InitLexer(const char *BufStart, const char *BufPtr,
   }
 
   Is_PragmaLexer = false;
-  IsInConflictMarker = false;
+  CurrentConflictMarkerState = CMK_None;
 
   // Start of the file is a start of line.
   IsAtStartOfLine = true;
@@ -187,9 +187,9 @@ Lexer *Lexer::Create_PragmaLexer(SourceLocation SpellingLoc,
 
   // Set the SourceLocation with the remapping information.  This ensures that
   // GetMappedTokenLoc will remap the tokens as they are lexed.
-  L->FileLoc = SM.createInstantiationLoc(SM.getLocForStartOfFile(SpellingFID),
-                                         ExpansionLocStart,
-                                         ExpansionLocEnd, TokLen);
+  L->FileLoc = SM.createExpansionLoc(SM.getLocForStartOfFile(SpellingFID),
+                                     ExpansionLocStart,
+                                     ExpansionLocEnd, TokLen);
 
   // Ensure that the lexer thinks it is inside a directive, so that end \n will
   // return an EOD token.
@@ -217,7 +217,7 @@ std::string Lexer::Stringify(const std::string &Str, bool Charify) {
 
 /// Stringify - Convert the specified string into a C string by escaping '\'
 /// and " characters.  This does not add surrounding ""'s to the string.
-void Lexer::Stringify(llvm::SmallVectorImpl<char> &Str) {
+void Lexer::Stringify(SmallVectorImpl<char> &Str) {
   for (unsigned i = 0, e = Str.size(); i != e; ++i) {
     if (Str[i] == '\\' || Str[i] == '"') {
       Str.insert(Str.begin()+i, '\\');
@@ -235,8 +235,8 @@ void Lexer::Stringify(llvm::SmallVectorImpl<char> &Str) {
 /// after trigraph expansion and escaped-newline folding.  In particular, this
 /// wants to get the true, uncanonicalized, spelling of things like digraphs
 /// UCNs, etc.
-llvm::StringRef Lexer::getSpelling(SourceLocation loc,
-                                   llvm::SmallVectorImpl<char> &buffer,
+StringRef Lexer::getSpelling(SourceLocation loc,
+                                   SmallVectorImpl<char> &buffer,
                                    const SourceManager &SM,
                                    const LangOptions &options,
                                    bool *invalid) {
@@ -245,10 +245,10 @@ llvm::StringRef Lexer::getSpelling(SourceLocation loc,
 
   // Try to the load the file buffer.
   bool invalidTemp = false;
-  llvm::StringRef file = SM.getBufferData(locInfo.first, &invalidTemp);
+  StringRef file = SM.getBufferData(locInfo.first, &invalidTemp);
   if (invalidTemp) {
     if (invalid) *invalid = true;
-    return llvm::StringRef();
+    return StringRef();
   }
 
   const char *tokenBegin = file.data() + locInfo.second;
@@ -263,7 +263,7 @@ llvm::StringRef Lexer::getSpelling(SourceLocation loc,
 
   // Common case:  no need for cleaning.
   if (!token.needsCleaning())
-    return llvm::StringRef(tokenBegin, length);
+    return StringRef(tokenBegin, length);
   
   // Hard case, we need to relex the characters into the string.
   buffer.clear();
@@ -275,7 +275,7 @@ llvm::StringRef Lexer::getSpelling(SourceLocation loc,
     ti += charSize;
   }
 
-  return llvm::StringRef(buffer.data(), buffer.size());
+  return StringRef(buffer.data(), buffer.size());
 }
 
 /// getSpelling() - Return the 'spelling' of this token.  The spelling of a
@@ -394,10 +394,10 @@ unsigned Lexer::MeasureTokenLength(SourceLocation Loc,
 
   // If this comes from a macro expansion, we really do want the macro name, not
   // the token this macro expanded to.
-  Loc = SM.getInstantiationLoc(Loc);
+  Loc = SM.getExpansionLoc(Loc);
   std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc);
   bool Invalid = false;
-  llvm::StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid);
+  StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid);
   if (Invalid)
     return 0;
 
@@ -415,15 +415,16 @@ unsigned Lexer::MeasureTokenLength(SourceLocation Loc,
   return TheTok.getLength();
 }
 
-SourceLocation Lexer::GetBeginningOfToken(SourceLocation Loc,
-                                          const SourceManager &SM,
-                                          const LangOptions &LangOpts) {
+static SourceLocation getBeginningOfFileToken(SourceLocation Loc,
+                                              const SourceManager &SM,
+                                              const LangOptions &LangOpts) {
+  assert(Loc.isFileID());
   std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc);
   if (LocInfo.first.isInvalid())
     return Loc;
   
   bool Invalid = false;
-  llvm::StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid);
+  StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid);
   if (Invalid)
     return Loc;
 
@@ -448,7 +449,7 @@ SourceLocation Lexer::GetBeginningOfToken(SourceLocation Loc,
   }
   
   // Create a lexer starting at the beginning of this token.
-  SourceLocation LexerStartLoc = Loc.getFileLocWithOffset(-LocInfo.second);
+  SourceLocation LexerStartLoc = Loc.getLocWithOffset(-LocInfo.second);
   Lexer TheLexer(LexerStartLoc, LangOpts, BufStart, LexStart, Buffer.end());
   TheLexer.SetCommentRetentionState(true);
   
@@ -474,6 +475,25 @@ SourceLocation Lexer::GetBeginningOfToken(SourceLocation Loc,
   return Loc;
 }
 
+SourceLocation Lexer::GetBeginningOfToken(SourceLocation Loc,
+                                          const SourceManager &SM,
+                                          const LangOptions &LangOpts) {
+ if (Loc.isFileID())
+   return getBeginningOfFileToken(Loc, SM, LangOpts);
+ 
+ if (!SM.isMacroArgExpansion(Loc))
+   return Loc;
+
+ SourceLocation FileLoc = SM.getSpellingLoc(Loc);
+ SourceLocation BeginFileLoc = getBeginningOfFileToken(FileLoc, SM, LangOpts);
+ std::pair<FileID, unsigned> FileLocInfo = SM.getDecomposedLoc(FileLoc);
+ std::pair<FileID, unsigned> BeginFileLocInfo= SM.getDecomposedLoc(BeginFileLoc);
+ assert(FileLocInfo.first == BeginFileLocInfo.first &&
+        FileLocInfo.second >= BeginFileLocInfo.second);
+ return Loc.getLocWithOffset(SM.getDecomposedLoc(BeginFileLoc).second -
+                                 SM.getDecomposedLoc(FileLoc).second);
+}
+
 namespace {
   enum PreambleDirectiveKind {
     PDK_Skipped,
@@ -484,21 +504,36 @@ namespace {
 }
 
 std::pair<unsigned, bool>
-Lexer::ComputePreamble(const llvm::MemoryBuffer *Buffer, unsigned MaxLines) {
+Lexer::ComputePreamble(const llvm::MemoryBuffer *Buffer,
+                       const LangOptions &Features, unsigned MaxLines) {
   // Create a lexer starting at the beginning of the file. Note that we use a
   // "fake" file source location at offset 1 so that the lexer will track our
   // position within the file.
   const unsigned StartOffset = 1;
   SourceLocation StartLoc = SourceLocation::getFromRawEncoding(StartOffset);
-  LangOptions LangOpts;
-  Lexer TheLexer(StartLoc, LangOpts, Buffer->getBufferStart(), 
+  Lexer TheLexer(StartLoc, Features, Buffer->getBufferStart(),
                  Buffer->getBufferStart(), Buffer->getBufferEnd());
   
   bool InPreprocessorDirective = false;
   Token TheTok;
   Token IfStartTok;
   unsigned IfCount = 0;
-  unsigned Line = 0;
+
+  unsigned MaxLineOffset = 0;
+  if (MaxLines) {
+    const char *CurPtr = Buffer->getBufferStart();
+    unsigned CurLine = 0;
+    while (CurPtr != Buffer->getBufferEnd()) {
+      char ch = *CurPtr++;
+      if (ch == '\n') {
+        ++CurLine;
+        if (CurLine == MaxLines)
+          break;
+      }
+    }
+    if (CurPtr != Buffer->getBufferEnd())
+      MaxLineOffset = CurPtr - Buffer->getBufferStart();
+  }
 
   do {
     TheLexer.LexFromRawLexer(TheTok);
@@ -522,11 +557,11 @@ Lexer::ComputePreamble(const llvm::MemoryBuffer *Buffer, unsigned MaxLines) {
     
     // Keep track of the # of lines in the preamble.
     if (TheTok.isAtStartOfLine()) {
-      ++Line;
+      unsigned TokOffset = TheTok.getLocation().getRawEncoding() - StartOffset;
 
       // If we were asked to limit the number of lines in the preamble,
       // and we're about to exceed that limit, we're done.
-      if (MaxLines && Line >= MaxLines)
+      if (MaxLineOffset && TokOffset >= MaxLineOffset)
         break;
     }
 
@@ -539,12 +574,12 @@ Lexer::ComputePreamble(const llvm::MemoryBuffer *Buffer, unsigned MaxLines) {
       Token HashTok = TheTok;
       InPreprocessorDirective = true;
       
-      // Figure out which direective this is. Since we're lexing raw tokens,
+      // Figure out which directive this is. Since we're lexing raw tokens,
       // we don't have an identifier table available. Instead, just look at
       // the raw identifier to recognize and categorize preprocessor directives.
       TheLexer.LexFromRawLexer(TheTok);
       if (TheTok.getKind() == tok::raw_identifier && !TheTok.needsCleaning()) {
-        llvm::StringRef Keyword(TheTok.getRawIdentifierData(),
+        StringRef Keyword(TheTok.getRawIdentifierData(),
                                 TheTok.getLength());
         PreambleDirectiveKind PDK
           = llvm::StringSwitch<PreambleDirectiveKind>(Keyword)
@@ -638,7 +673,7 @@ SourceLocation Lexer::AdvanceToTokenCharacter(SourceLocation TokStart,
   // chars, this method is extremely fast.
   while (Lexer::isObviouslySimpleCharacter(*TokPtr)) {
     if (CharNo == 0)
-      return TokStart.getFileLocWithOffset(PhysOffset);
+      return TokStart.getLocWithOffset(PhysOffset);
     ++TokPtr, --CharNo, ++PhysOffset;
   }
   
@@ -658,7 +693,7 @@ SourceLocation Lexer::AdvanceToTokenCharacter(SourceLocation TokStart,
   if (!Lexer::isObviouslySimpleCharacter(*TokPtr))
     PhysOffset += Lexer::SkipEscapedNewLines(TokPtr)-TokPtr;
   
-  return TokStart.getFileLocWithOffset(PhysOffset);
+  return TokStart.getLocWithOffset(PhysOffset);
 }
 
 /// \brief Computes the source location just past the end of the
@@ -687,7 +722,7 @@ SourceLocation Lexer::getLocForEndOfToken(SourceLocation Loc, unsigned Offset,
       return SourceLocation(); // Points inside the macro expansion.
 
     // Continue and find the location just after the macro expansion.
-    Loc = SM.getInstantiationRange(Loc).second;
+    Loc = SM.getExpansionRange(Loc).second;
   }
 
   unsigned Len = Lexer::MeasureTokenLength(Loc, SM, Features);
@@ -696,14 +731,14 @@ SourceLocation Lexer::getLocForEndOfToken(SourceLocation Loc, unsigned Offset,
   else
     return Loc;
   
-  return Loc.getFileLocWithOffset(Len);
+  return Loc.getLocWithOffset(Len);
 }
 
 /// \brief Returns true if the given MacroID location points at the first
 /// token of the macro expansion.
 bool Lexer::isAtStartOfMacroExpansion(SourceLocation loc,
-                                          const SourceManager &SM,
-                                          const LangOptions &LangOpts) {
+                                      const SourceManager &SM,
+                                      const LangOptions &LangOpts) {
   assert(loc.isValid() && loc.isMacroID() && "Expected a valid macro loc");
 
   std::pair<FileID, unsigned> infoLoc = SM.getDecomposedLoc(loc);
@@ -713,8 +748,7 @@ bool Lexer::isAtStartOfMacroExpansion(SourceLocation loc,
     return false; // Does not point at the start of token.
 
   SourceLocation expansionLoc =
-    SM.getSLocEntry(infoLoc.first)
-      .getInstantiation().getInstantiationLocStart();
+    SM.getSLocEntry(infoLoc.first).getExpansion().getExpansionLocStart();
   if (expansionLoc.isFileID())
     return true; // No other macro expansions, this is the first.
 
@@ -734,17 +768,15 @@ bool Lexer::isAtEndOfMacroExpansion(SourceLocation loc,
     return false;
 
   FileID FID = SM.getFileID(loc);
-  SourceLocation afterLoc = loc.getFileLocWithOffset(tokLen+1);
-  if (!SM.isBeforeInSourceLocationOffset(afterLoc, SM.getNextOffset()))
-    return true; // We got past the last FileID, this points to the last token.
+  SourceLocation afterLoc = loc.getLocWithOffset(tokLen+1);
+  if (SM.isInFileID(afterLoc, FID))
+    return false; // Still in the same FileID, does not point to the last token.
 
   // FIXME: If the token comes from the macro token paste operator ('##')
   // or the stringify operator ('#') this function will always return false;
-  if (FID == SM.getFileID(afterLoc))
-    return false; // Still in the same FileID, does not point to the last token.
-  
+
   SourceLocation expansionLoc =
-    SM.getSLocEntry(FID).getInstantiation().getInstantiationLocEnd();
+    SM.getSLocEntry(FID).getExpansion().getExpansionLocEnd();
   if (expansionLoc.isFileID())
     return true; // No other macro expansions.
 
@@ -761,7 +793,8 @@ enum {
   CHAR_LETTER   = 0x04,  // a-z,A-Z
   CHAR_NUMBER   = 0x08,  // 0-9
   CHAR_UNDER    = 0x10,  // _
-  CHAR_PERIOD   = 0x20   // .
+  CHAR_PERIOD   = 0x20,  // .
+  CHAR_RAWDEL   = 0x40   // {}[]#<>%:;?*+-/^&|~!=,"'
 };
 
 // Statically initialize CharInfo table based on ASCII character set
@@ -786,20 +819,20 @@ static const unsigned char CharInfo[256] =
    0           , 0           , 0           , 0           ,
 //32 SP         33  !         34  "         35  #
 //36  $         37  %         38  &         39  '
-   CHAR_HORZ_WS, 0           , 0           , 0           ,
-   0           , 0           , 0           , 0           ,
+   CHAR_HORZ_WS, CHAR_RAWDEL , CHAR_RAWDEL , CHAR_RAWDEL ,
+   0           , CHAR_RAWDEL , CHAR_RAWDEL , CHAR_RAWDEL ,
 //40  (         41  )         42  *         43  +
 //44  ,         45  -         46  .         47  /
-   0           , 0           , 0           , 0           ,
-   0           , 0           , CHAR_PERIOD , 0           ,
+   0           , 0           , CHAR_RAWDEL , CHAR_RAWDEL ,
+   CHAR_RAWDEL , CHAR_RAWDEL , CHAR_PERIOD , CHAR_RAWDEL ,
 //48  0         49  1         50  2         51  3
 //52  4         53  5         54  6         55  7
    CHAR_NUMBER , CHAR_NUMBER , CHAR_NUMBER , CHAR_NUMBER ,
    CHAR_NUMBER , CHAR_NUMBER , CHAR_NUMBER , CHAR_NUMBER ,
 //56  8         57  9         58  :         59  ;
 //60  <         61  =         62  >         63  ?
-   CHAR_NUMBER , CHAR_NUMBER , 0           , 0           ,
-   0           , 0           , 0           , 0           ,
+   CHAR_NUMBER , CHAR_NUMBER , CHAR_RAWDEL , CHAR_RAWDEL ,
+   CHAR_RAWDEL , CHAR_RAWDEL , CHAR_RAWDEL , CHAR_RAWDEL ,
 //64  @         65  A         66  B         67  C
 //68  D         69  E         70  F         71  G
    0           , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
@@ -814,8 +847,8 @@ static const unsigned char CharInfo[256] =
    CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
 //88  X         89  Y         90  Z         91  [
 //92  \         93  ]         94  ^         95  _
-   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , 0           ,
-   0           , 0           , 0           , CHAR_UNDER  ,
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_RAWDEL ,
+   0           , CHAR_RAWDEL , CHAR_RAWDEL , CHAR_UNDER  ,
 //96  `         97  a         98  b         99  c
 //100  d       101  e        102  f        103  g
    0           , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
@@ -829,9 +862,9 @@ static const unsigned char CharInfo[256] =
    CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
    CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
 //120  x       121  y        122  z        123  {
-//124  |        125  }        126  ~        127 DEL
-   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , 0           ,
-   0           , 0           , 0           , 0
+//124  |       125  }        126  ~        127 DEL
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_RAWDEL ,
+   CHAR_RAWDEL , CHAR_RAWDEL , CHAR_RAWDEL , 0
 };
 
 static void InitCharacterInfo() {
@@ -869,6 +902,12 @@ static inline bool isHorizontalWhitespace(unsigned char c) {
   return (CharInfo[c] & CHAR_HORZ_WS) ? true : false;
 }
 
+/// isVerticalWhitespace - Return true if this character is vertical
+/// whitespace: '\n', '\r'.  Note that this returns false for '\0'.
+static inline bool isVerticalWhitespace(unsigned char c) {
+  return (CharInfo[c] & CHAR_VERT_WS) ? true : false;
+}
+
 /// isWhitespace - Return true if this character is horizontal or vertical
 /// whitespace: ' ', '\t', '\f', '\v', '\n', '\r'.  Note that this returns false
 /// for '\0'.
@@ -883,6 +922,14 @@ static inline bool isNumberBody(unsigned char c) {
     true : false;
 }
 
+/// isRawStringDelimBody - Return true if this is the body character of a
+/// raw string delimiter.
+static inline bool isRawStringDelimBody(unsigned char c) {
+  return (CharInfo[c] &
+          (CHAR_LETTER|CHAR_NUMBER|CHAR_UNDER|CHAR_PERIOD|CHAR_RAWDEL)) ?
+    true : false;
+}
+
 
 //===----------------------------------------------------------------------===//
 // Diagnostics forwarding code.
@@ -907,14 +954,14 @@ static SourceLocation GetMappedTokenLoc(Preprocessor &PP,
   // Create a new SLoc which is expanded from Expansion(FileLoc) but whose
   // characters come from spelling(FileLoc)+Offset.
   SourceLocation SpellingLoc = SM.getSpellingLoc(FileLoc);
-  SpellingLoc = SpellingLoc.getFileLocWithOffset(CharNo);
+  SpellingLoc = SpellingLoc.getLocWithOffset(CharNo);
 
   // Figure out the expansion loc range, which is the range covered by the
   // original _Pragma(...) sequence.
   std::pair<SourceLocation,SourceLocation> II =
-    SM.getImmediateInstantiationRange(FileLoc);
+    SM.getImmediateExpansionRange(FileLoc);
 
-  return SM.createInstantiationLoc(SpellingLoc, II.first, II.second, TokLen);
+  return SM.createExpansionLoc(SpellingLoc, II.first, II.second, TokLen);
 }
 
 /// getSourceLocation - Return a source location identifier for the specified
@@ -928,7 +975,7 @@ SourceLocation Lexer::getSourceLocation(const char *Loc,
   // the file id from FileLoc with the offset specified.
   unsigned CharNo = Loc-BufferStart;
   if (FileLoc.isFileID())
-    return FileLoc.getFileLocWithOffset(CharNo);
+    return FileLoc.getLocWithOffset(CharNo);
 
   // Otherwise, this is the _Pragma lexer case, which pretends that all of the
   // tokens are lexed from where the _Pragma was defined.
@@ -978,7 +1025,7 @@ static char DecodeTrigraphChar(const char *CP, Lexer *L) {
   }
 
   if (!L->isLexingRawMode())
-    L->Diag(CP-2, diag::trigraph_converted) << llvm::StringRef(&Res, 1);
+    L->Diag(CP-2, diag::trigraph_converted) << StringRef(&Res, 1);
   return Res;
 }
 
@@ -1028,6 +1075,59 @@ const char *Lexer::SkipEscapedNewLines(const char *P) {
   }
 }
 
+/// \brief Checks that the given token is the first token that occurs after the
+/// given location (this excludes comments and whitespace). Returns the location
+/// immediately after the specified token. If the token is not found or the
+/// location is inside a macro, the returned source location will be invalid.
+SourceLocation Lexer::findLocationAfterToken(SourceLocation Loc,
+                                        tok::TokenKind TKind,
+                                        const SourceManager &SM,
+                                        const LangOptions &LangOpts,
+                                        bool SkipTrailingWhitespaceAndNewLine) {
+  if (Loc.isMacroID()) {
+    if (!Lexer::isAtEndOfMacroExpansion(Loc, SM, LangOpts))
+      return SourceLocation();
+    Loc = SM.getExpansionRange(Loc).second;
+  }
+  Loc = Lexer::getLocForEndOfToken(Loc, 0, SM, LangOpts);
+
+  // Break down the source location.
+  std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc);
+
+  // Try to load the file buffer.
+  bool InvalidTemp = false;
+  llvm::StringRef File = SM.getBufferData(LocInfo.first, &InvalidTemp);
+  if (InvalidTemp)
+    return SourceLocation();
+
+  const char *TokenBegin = File.data() + LocInfo.second;
+
+  // Lex from the start of the given location.
+  Lexer lexer(SM.getLocForStartOfFile(LocInfo.first), LangOpts, File.begin(),
+                                      TokenBegin, File.end());
+  // Find the token.
+  Token Tok;
+  lexer.LexFromRawLexer(Tok);
+  if (Tok.isNot(TKind))
+    return SourceLocation();
+  SourceLocation TokenLoc = Tok.getLocation();
+
+  // Calculate how much whitespace needs to be skipped if any.
+  unsigned NumWhitespaceChars = 0;
+  if (SkipTrailingWhitespaceAndNewLine) {
+    const char *TokenEnd = SM.getCharacterData(TokenLoc) +
+                           Tok.getLength();
+    unsigned char C = *TokenEnd;
+    while (isHorizontalWhitespace(C)) {
+      C = *(++TokenEnd);
+      NumWhitespaceChars++;
+    }
+    if (isVerticalWhitespace(C))
+      NumWhitespaceChars++;
+  }
+
+  return TokenLoc.getLocWithOffset(Tok.getLength() + NumWhitespaceChars);
+}
 
 /// getCharAndSizeSlow - Peek a single 'character' from the specified buffer,
 /// get its size, and return it.  This is tricky in several cases:
@@ -1191,6 +1291,7 @@ FinishIdentifier:
     // preprocessor, which may macro expand it or something.
     if (II->isHandleIdentifierCase())
       PP->HandleIdentifier(Result);
+    
     return;
   }
 
@@ -1252,13 +1353,12 @@ void Lexer::LexNumericConstant(Token &Result, const char *CurPtr) {
   if ((C == '-' || C == '+') && (PrevCh == 'E' || PrevCh == 'e')) {
     // If we are in Microsoft mode, don't continue if the constant is hex.
     // For example, MSVC will accept the following as 3 tokens: 0x1234567e+1
-    if (!Features.Microsoft || !isHexaLiteral(BufferPtr, Features))
+    if (!Features.MicrosoftExt || !isHexaLiteral(BufferPtr, Features))
       return LexNumericConstant(Result, ConsumeChar(CurPtr, Size, Result));
   }
 
   // If we have a hex FP constant, continue.
-  if ((C == '-' || C == '+') && (PrevCh == 'P' || PrevCh == 'p') &&
-      !Features.CPlusPlus0x)
+  if ((C == '-' || C == '+') && (PrevCh == 'P' || PrevCh == 'p'))
     return LexNumericConstant(Result, ConsumeChar(CurPtr, Size, Result));
 
   // Update the location of token as well as BufferPtr.
@@ -1268,10 +1368,17 @@ void Lexer::LexNumericConstant(Token &Result, const char *CurPtr) {
 }
 
 /// LexStringLiteral - Lex the remainder of a string literal, after having lexed
-/// either " or L".
-void Lexer::LexStringLiteral(Token &Result, const char *CurPtr, bool Wide) {
+/// either " or L" or u8" or u" or U".
+void Lexer::LexStringLiteral(Token &Result, const char *CurPtr,
+                             tok::TokenKind Kind) {
   const char *NulCharacter = 0; // Does this string contain the \0 character?
 
+  if (!isLexingRawMode() &&
+      (Kind == tok::utf8_string_literal ||
+       Kind == tok::utf16_string_literal ||
+       Kind == tok::utf32_string_literal))
+    Diag(BufferPtr, diag::warn_cxx98_compat_unicode_literal);
+
   char C = getAndAdvanceChar(CurPtr, Result);
   while (C != '"') {
     // Skip escaped characters.  Escaped newlines will already be processed by
@@ -1281,16 +1388,21 @@ void Lexer::LexStringLiteral(Token &Result, const char *CurPtr, bool Wide) {
     
     if (C == '\n' || C == '\r' ||             // Newline.
         (C == 0 && CurPtr-1 == BufferEnd)) {  // End of file.
-      if (C == 0 && PP && PP->isCodeCompletionFile(FileLoc))
-        PP->CodeCompleteNaturalLanguage();
-      else if (!isLexingRawMode() && !Features.AsmPreprocessor)
+      if (!isLexingRawMode() && !Features.AsmPreprocessor)
         Diag(BufferPtr, diag::warn_unterminated_string);
       FormTokenWithChars(Result, CurPtr-1, tok::unknown);
       return;
     }
     
-    if (C == 0)
+    if (C == 0) {
+      if (isCodeCompletionPoint(CurPtr-1)) {
+        PP->CodeCompleteNaturalLanguage();
+        FormTokenWithChars(Result, CurPtr-1, tok::unknown);
+        return cutOffLexing();
+      }
+
       NulCharacter = CurPtr-1;
+    }
     C = getAndAdvanceChar(CurPtr, Result);
   }
 
@@ -1300,8 +1412,82 @@ void Lexer::LexStringLiteral(Token &Result, const char *CurPtr, bool Wide) {
 
   // Update the location of the token as well as the BufferPtr instance var.
   const char *TokStart = BufferPtr;
-  FormTokenWithChars(Result, CurPtr,
-                     Wide ? tok::wide_string_literal : tok::string_literal);
+  FormTokenWithChars(Result, CurPtr, Kind);
+  Result.setLiteralData(TokStart);
+}
+
+/// LexRawStringLiteral - Lex the remainder of a raw string literal, after
+/// having lexed R", LR", u8R", uR", or UR".
+void Lexer::LexRawStringLiteral(Token &Result, const char *CurPtr,
+                                tok::TokenKind Kind) {
+  // This function doesn't use getAndAdvanceChar because C++0x [lex.pptoken]p3:
+  //  Between the initial and final double quote characters of the raw string,
+  //  any transformations performed in phases 1 and 2 (trigraphs,
+  //  universal-character-names, and line splicing) are reverted.
+
+  if (!isLexingRawMode())
+    Diag(BufferPtr, diag::warn_cxx98_compat_raw_string_literal);
+
+  unsigned PrefixLen = 0;
+
+  while (PrefixLen != 16 && isRawStringDelimBody(CurPtr[PrefixLen]))
+    ++PrefixLen;
+
+  // If the last character was not a '(', then we didn't lex a valid delimiter.
+  if (CurPtr[PrefixLen] != '(') {
+    if (!isLexingRawMode()) {
+      const char *PrefixEnd = &CurPtr[PrefixLen];
+      if (PrefixLen == 16) {
+        Diag(PrefixEnd, diag::err_raw_delim_too_long);
+      } else {
+        Diag(PrefixEnd, diag::err_invalid_char_raw_delim)
+          << StringRef(PrefixEnd, 1);
+      }
+    }
+
+    // Search for the next '"' in hopes of salvaging the lexer. Unfortunately,
+    // it's possible the '"' was intended to be part of the raw string, but
+    // there's not much we can do about that.
+    while (1) {
+      char C = *CurPtr++;
+
+      if (C == '"')
+        break;
+      if (C == 0 && CurPtr-1 == BufferEnd) {
+        --CurPtr;
+        break;
+      }
+    }
+
+    FormTokenWithChars(Result, CurPtr, tok::unknown);
+    return;
+  }
+
+  // Save prefix and move CurPtr past it
+  const char *Prefix = CurPtr;
+  CurPtr += PrefixLen + 1; // skip over prefix and '('
+
+  while (1) {
+    char C = *CurPtr++;
+
+    if (C == ')') {
+      // Check for prefix match and closing quote.
+      if (strncmp(CurPtr, Prefix, PrefixLen) == 0 && CurPtr[PrefixLen] == '"') {
+        CurPtr += PrefixLen + 1; // skip over prefix and '"'
+        break;
+      }
+    } else if (C == 0 && CurPtr-1 == BufferEnd) { // End of file.
+      if (!isLexingRawMode())
+        Diag(BufferPtr, diag::err_unterminated_raw_string)
+          << StringRef(Prefix, PrefixLen);
+      FormTokenWithChars(Result, CurPtr-1, tok::unknown);
+      return;
+    }
+  }
+
+  // Update the location of token as well as BufferPtr.
+  const char *TokStart = BufferPtr;
+  FormTokenWithChars(Result, CurPtr, Kind);
   Result.setLiteralData(TokStart);
 }
 
@@ -1317,7 +1503,8 @@ void Lexer::LexAngledStringLiteral(Token &Result, const char *CurPtr) {
       // Skip the escaped character.
       C = getAndAdvanceChar(CurPtr, Result);
     } else if (C == '\n' || C == '\r' ||             // Newline.
-               (C == 0 && CurPtr-1 == BufferEnd)) {  // End of file.
+               (C == 0 && (CurPtr-1 == BufferEnd ||  // End of file.
+                           isCodeCompletionPoint(CurPtr-1)))) {
       // If the filename is unterminated, then it must just be a lone <
       // character.  Return this as such.
       FormTokenWithChars(Result, AfterLessPos, tok::less);
@@ -1340,10 +1527,15 @@ void Lexer::LexAngledStringLiteral(Token &Result, const char *CurPtr) {
 
 
 /// LexCharConstant - Lex the remainder of a character constant, after having
-/// lexed either ' or L'.
-void Lexer::LexCharConstant(Token &Result, const char *CurPtr) {
+/// lexed either ' or L' or u' or U'.
+void Lexer::LexCharConstant(Token &Result, const char *CurPtr,
+                            tok::TokenKind Kind) {
   const char *NulCharacter = 0; // Does this character contain the \0 character?
 
+  if (!isLexingRawMode() &&
+      (Kind == tok::utf16_char_constant || Kind == tok::utf32_char_constant))
+    Diag(BufferPtr, diag::warn_cxx98_compat_unicode_literal);
+
   char C = getAndAdvanceChar(CurPtr, Result);
   if (C == '\'') {
     if (!isLexingRawMode() && !Features.AsmPreprocessor)
@@ -1360,13 +1552,17 @@ void Lexer::LexCharConstant(Token &Result, const char *CurPtr) {
       C = getAndAdvanceChar(CurPtr, Result);
     } else if (C == '\n' || C == '\r' ||             // Newline.
                (C == 0 && CurPtr-1 == BufferEnd)) {  // End of file.
-      if (C == 0 && PP && PP->isCodeCompletionFile(FileLoc))
-        PP->CodeCompleteNaturalLanguage();
-      else if (!isLexingRawMode() && !Features.AsmPreprocessor)
+      if (!isLexingRawMode() && !Features.AsmPreprocessor)
         Diag(BufferPtr, diag::warn_unterminated_char);
       FormTokenWithChars(Result, CurPtr-1, tok::unknown);
       return;
     } else if (C == 0) {
+      if (isCodeCompletionPoint(CurPtr-1)) {
+        PP->CodeCompleteNaturalLanguage();
+        FormTokenWithChars(Result, CurPtr-1, tok::unknown);
+        return cutOffLexing();
+      }
+
       NulCharacter = CurPtr-1;
     }
     C = getAndAdvanceChar(CurPtr, Result);
@@ -1378,7 +1574,7 @@ void Lexer::LexCharConstant(Token &Result, const char *CurPtr) {
 
   // Update the location of token as well as BufferPtr.
   const char *TokStart = BufferPtr;
-  FormTokenWithChars(Result, CurPtr, tok::char_constant);
+  FormTokenWithChars(Result, CurPtr, Kind);
   Result.setLiteralData(TokStart);
 }
 
@@ -1451,20 +1647,28 @@ bool Lexer::SkipBCPLComment(Token &Result, const char *CurPtr) {
   char C;
   do {
     C = *CurPtr;
-    // FIXME: Speedup BCPL comment lexing.  Just scan for a \n or \r character.
-    // If we find a \n character, scan backwards, checking to see if it's an
-    // escaped newline, like we do for block comments.
-
     // Skip over characters in the fast loop.
     while (C != 0 &&                // Potentially EOF.
-           C != '\\' &&             // Potentially escaped newline.
-           C != '?' &&              // Potentially trigraph.
            C != '\n' && C != '\r')  // Newline or DOS-style newline.
       C = *++CurPtr;
 
-    // If this is a newline, we're done.
-    if (C == '\n' || C == '\r')
-      break;  // Found the newline? Break out!
+    const char *NextLine = CurPtr;
+    if (C != 0) {
+      // We found a newline, see if it's escaped.
+      const char *EscapePtr = CurPtr-1;
+      while (isHorizontalWhitespace(*EscapePtr)) // Skip whitespace.
+        --EscapePtr;
+
+      if (*EscapePtr == '\\') // Escaped newline.
+        CurPtr = EscapePtr;
+      else if (EscapePtr[0] == '/' && EscapePtr[-1] == '?' &&
+               EscapePtr[-2] == '?') // Trigraph-escaped newline.
+        CurPtr = EscapePtr-2;
+      else
+        break; // This is a newline, we're done.
+
+      C = *CurPtr;
+    }
 
     // Otherwise, this is a hard case.  Fall back on getAndAdvanceChar to
     // properly decode the character.  Read it in raw mode to avoid emitting
@@ -1476,6 +1680,13 @@ bool Lexer::SkipBCPLComment(Token &Result, const char *CurPtr) {
     C = getAndAdvanceChar(CurPtr, Result);
     LexingRawMode = OldRawMode;
 
+    // If we only read only one character, then no special handling is needed.
+    // We're done and can skip forward to the newline.
+    if (C != 0 && CurPtr == OldPtr+1) {
+      CurPtr = NextLine;
+      break;
+    }
+
     // If the char that we finally got was a \n, then we must have had something
     // like \<newline><newline>.  We don't want to have consumed the second
     // newline, we want CurPtr, to end up pointing to it down below.
@@ -1492,9 +1703,9 @@ bool Lexer::SkipBCPLComment(Token &Result, const char *CurPtr) {
         if (OldPtr[0] == '\n' || OldPtr[0] == '\r') {
           // Okay, we found a // comment that ends in a newline, if the next
           // line is also a // comment, but has spaces, don't emit a diagnostic.
-          if (isspace(C)) {
+          if (isWhitespace(C)) {
             const char *ForwardPtr = CurPtr;
-            while (isspace(*ForwardPtr))  // Skip whitespace.
+            while (isWhitespace(*ForwardPtr))  // Skip whitespace.
               ++ForwardPtr;
             if (ForwardPtr[0] == '/' && ForwardPtr[1] == '/')
               break;
@@ -1507,12 +1718,16 @@ bool Lexer::SkipBCPLComment(Token &Result, const char *CurPtr) {
     }
 
     if (CurPtr == BufferEnd+1) { 
-      if (PP && PP->isCodeCompletionFile(FileLoc))
-        PP->CodeCompleteNaturalLanguage();
-
       --CurPtr; 
       break; 
     }
+
+    if (C == '\0' && isCodeCompletionPoint(CurPtr-1)) {
+      PP->CodeCompleteNaturalLanguage();
+      cutOffLexing();
+      return false;
+    }
+
   } while (C != '\n' && C != '\r');
 
   // Found but did not consume the newline.  Notify comment handlers about the
@@ -1573,7 +1788,7 @@ bool Lexer::SaveBCPLComment(Token &Result, const char *CurPtr) {
 
   Result.setKind(tok::comment);
   PP->CreateString(&Spelling[0], Spelling.size(), Result,
-                   Result.getLocation());
+                   Result.getLocation(), Result.getLocation());
   return true;
 }
 
@@ -1667,8 +1882,7 @@ bool Lexer::SkipBlockComment(Token &Result, const char *CurPtr) {
   unsigned char C = getCharAndSize(CurPtr, CharSize);
   CurPtr += CharSize;
   if (C == 0 && CurPtr == BufferEnd+1) {
-    if (!isLexingRawMode() &&
-        !PP->isCodeCompletionFile(FileLoc))
+    if (!isLexingRawMode())
       Diag(BufferPtr, diag::err_unterminated_block_comment);
     --CurPtr;
 
@@ -1691,7 +1905,10 @@ bool Lexer::SkipBlockComment(Token &Result, const char *CurPtr) {
   while (1) {
     // Skip over all non-interesting characters until we find end of buffer or a
     // (probably ending) '/' character.
-    if (CurPtr + 24 < BufferEnd) {
+    if (CurPtr + 24 < BufferEnd &&
+        // If there is a code-completion point avoid the fast scan because it
+        // doesn't check for '\0'.
+        !(PP && PP->getCodeCompletionFileLoc() == FileLoc)) {
       // While not aligned to a 16-byte boundary.
       while (C != '/' && ((intptr_t)CurPtr & 0x0F) != 0)
         C = *CurPtr++;
@@ -1751,9 +1968,7 @@ bool Lexer::SkipBlockComment(Token &Result, const char *CurPtr) {
           Diag(CurPtr-1, diag::warn_nested_block_comment);
       }
     } else if (C == 0 && CurPtr == BufferEnd+1) {
-      if (PP && PP->isCodeCompletionFile(FileLoc))
-        PP->CodeCompleteNaturalLanguage();
-      else if (!isLexingRawMode())
+      if (!isLexingRawMode())
         Diag(BufferPtr, diag::err_unterminated_block_comment);
       // Note: the user probably forgot a */.  We could continue immediately
       // after the /*, but this would involve lexing a lot of what really is the
@@ -1769,7 +1984,12 @@ bool Lexer::SkipBlockComment(Token &Result, const char *CurPtr) {
 
       BufferPtr = CurPtr;
       return false;
+    } else if (C == '\0' && isCodeCompletionPoint(CurPtr-1)) {
+      PP->CodeCompleteNaturalLanguage();
+      cutOffLexing();
+      return false;
     }
+
     C = *CurPtr++;
   }
 
@@ -1826,6 +2046,12 @@ std::string Lexer::ReadToEndOfLine() {
     case 0:  // Null.
       // Found end of file?
       if (CurPtr-1 != BufferEnd) {
+        if (isCodeCompletionPoint(CurPtr-1)) {
+          PP->CodeCompleteNaturalLanguage();
+          cutOffLexing();
+          return Result;
+        }
+
         // Nope, normal character, continue.
         Result += Char;
         break;
@@ -1840,8 +2066,8 @@ std::string Lexer::ReadToEndOfLine() {
       // Next, lex the character, which should handle the EOD transition.
       Lex(Tmp);
       if (Tmp.is(tok::code_completion)) {
-        if (PP && PP->getCodeCompletionHandler())
-          PP->getCodeCompletionHandler()->CodeCompleteNaturalLanguage();
+        if (PP)
+          PP->CodeCompleteNaturalLanguage();
         Lex(Tmp);
       }
       assert(Tmp.is(tok::eod) && "Unexpected token!");
@@ -1857,22 +2083,6 @@ std::string Lexer::ReadToEndOfLine() {
 /// This returns true if Result contains a token, false if PP.Lex should be
 /// called again.
 bool Lexer::LexEndOfFile(Token &Result, const char *CurPtr) {
-  // Check if we are performing code completion.
-  if (PP && PP->isCodeCompletionFile(FileLoc)) {
-    // We're at the end of the file, but we've been asked to consider the
-    // end of the file to be a code-completion token. Return the
-    // code-completion token.
-    Result.startToken();
-    FormTokenWithChars(Result, CurPtr, tok::code_completion);
-    
-    // Only do the eof -> code_completion translation once.
-    PP->SetCodeCompletionPoint(0, 0, 0);
-    
-    // Silence any diagnostics that occur once we hit the code-completion point.
-    PP->getDiagnostics().setSuppressAllDiagnostics(true);
-    return true;
-  }
-
   // If we hit the end of the file while parsing a preprocessor directive,
   // end the preprocessor directive first.  The next token returned will
   // then be the end of file.
@@ -1900,7 +2110,7 @@ bool Lexer::LexEndOfFile(Token &Result, const char *CurPtr) {
 
   // If we are in a #if directive, emit an error.
   while (!ConditionalStack.empty()) {
-    if (!PP->isCodeCompletionFile(FileLoc))
+    if (PP->getCodeCompletionFileLoc() != FileLoc)
       PP->Diag(ConditionalStack.back().IfLoc,
                diag::err_pp_unterminated_conditional);
     ConditionalStack.pop_back();
@@ -1951,15 +2161,18 @@ unsigned Lexer::isNextPPTokenLParen() {
 }
 
 /// FindConflictEnd - Find the end of a version control conflict marker.
-static const char *FindConflictEnd(const char *CurPtr, const char *BufferEnd) {
-  llvm::StringRef RestOfBuffer(CurPtr+7, BufferEnd-CurPtr-7);
-  size_t Pos = RestOfBuffer.find(">>>>>>>");
-  while (Pos != llvm::StringRef::npos) {
+static const char *FindConflictEnd(const char *CurPtr, const char *BufferEnd,
+                                   ConflictMarkerKind CMK) {
+  const char *Terminator = CMK == CMK_Perforce ? "<<<<\n" : ">>>>>>>";
+  size_t TermLen = CMK == CMK_Perforce ? 5 : 7;
+  StringRef RestOfBuffer(CurPtr+TermLen, BufferEnd-CurPtr-TermLen);
+  size_t Pos = RestOfBuffer.find(Terminator);
+  while (Pos != StringRef::npos) {
     // Must occur at start of line.
     if (RestOfBuffer[Pos-1] != '\r' &&
         RestOfBuffer[Pos-1] != '\n') {
-      RestOfBuffer = RestOfBuffer.substr(Pos+7);
-      Pos = RestOfBuffer.find(">>>>>>>");
+      RestOfBuffer = RestOfBuffer.substr(Pos+TermLen);
+      Pos = RestOfBuffer.find(Terminator);
       continue;
     }
     return RestOfBuffer.data()+Pos;
@@ -1977,23 +2190,25 @@ bool Lexer::IsStartOfConflictMarker(const char *CurPtr) {
       CurPtr[-1] != '\n' && CurPtr[-1] != '\r')
     return false;
   
-  // Check to see if we have <<<<<<<.
-  if (BufferEnd-CurPtr < 8 ||
-      llvm::StringRef(CurPtr, 7) != "<<<<<<<")
+  // Check to see if we have <<<<<<< or >>>>.
+  if ((BufferEnd-CurPtr < 8 || StringRef(CurPtr, 7) != "<<<<<<<") &&
+      (BufferEnd-CurPtr < 6 || StringRef(CurPtr, 5) != ">>>> "))
     return false;
 
   // If we have a situation where we don't care about conflict markers, ignore
   // it.
-  if (IsInConflictMarker || isLexingRawMode())
+  if (CurrentConflictMarkerState || isLexingRawMode())
     return false;
   
-  // Check to see if there is a >>>>>>> somewhere in the buffer at the start of
-  // a line to terminate this conflict marker.
-  if (FindConflictEnd(CurPtr, BufferEnd)) {
+  ConflictMarkerKind Kind = *CurPtr == '<' ? CMK_Normal : CMK_Perforce;
+
+  // Check to see if there is an ending marker somewhere in the buffer at the
+  // start of a line to terminate this conflict marker.
+  if (FindConflictEnd(CurPtr, BufferEnd, Kind)) {
     // We found a match.  We are really in a conflict marker.
     // Diagnose this, and ignore to the end of line.
     Diag(CurPtr, diag::err_conflict_marker);
-    IsInConflictMarker = true;
+    CurrentConflictMarkerState = Kind;
     
     // Skip ahead to the end of line.  We know this exists because the
     // end-of-conflict marker starts with \r or \n.
@@ -2010,10 +2225,10 @@ bool Lexer::IsStartOfConflictMarker(const char *CurPtr) {
 }
 
 
-/// HandleEndOfConflictMarker - If this is a '=======' or '|||||||' or '>>>>>>>'
-/// marker, then it is the end of a conflict marker.  Handle it by ignoring up
-/// until the end of the line.  This returns true if it is a conflict marker and
-/// false if not.
+/// HandleEndOfConflictMarker - If this is a '====' or '||||' or '>>>>', or if
+/// it is '<<<<' and the conflict marker started with a '>>>>' marker, then it
+/// is the end of a conflict marker.  Handle it by ignoring up until the end of
+/// the line.  This returns true if it is a conflict marker and false if not.
 bool Lexer::HandleEndOfConflictMarker(const char *CurPtr) {
   // Only a conflict marker if it starts at the beginning of a line.
   if (CurPtr != BufferStart &&
@@ -2022,18 +2237,19 @@ bool Lexer::HandleEndOfConflictMarker(const char *CurPtr) {
   
   // If we have a situation where we don't care about conflict markers, ignore
   // it.
-  if (!IsInConflictMarker || isLexingRawMode())
+  if (!CurrentConflictMarkerState || isLexingRawMode())
     return false;
   
-  // Check to see if we have the marker (7 characters in a row).
-  for (unsigned i = 1; i != 7; ++i)
+  // Check to see if we have the marker (4 characters in a row).
+  for (unsigned i = 1; i != 4; ++i)
     if (CurPtr[i] != CurPtr[0])
       return false;
   
   // If we do have it, search for the end of the conflict marker.  This could
   // fail if it got skipped with a '#if 0' or something.  Note that CurPtr might
   // be the end of conflict marker.
-  if (const char *End = FindConflictEnd(CurPtr, BufferEnd)) {
+  if (const char *End = FindConflictEnd(CurPtr, BufferEnd,
+                                        CurrentConflictMarkerState)) {
     CurPtr = End;
     
     // Skip ahead to the end of line.
@@ -2043,13 +2259,22 @@ bool Lexer::HandleEndOfConflictMarker(const char *CurPtr) {
     BufferPtr = CurPtr;
     
     // No longer in the conflict marker.
-    IsInConflictMarker = false;
+    CurrentConflictMarkerState = CMK_None;
     return true;
   }
   
   return false;
 }
 
+bool Lexer::isCodeCompletionPoint(const char *CurPtr) const {
+  if (PP && PP->isCodeCompletionEnabled()) {
+    SourceLocation Loc = FileLoc.getLocWithOffset(CurPtr-BufferStart);
+    return Loc == PP->getCodeCompletionLoc();
+  }
+
+  return false;
+}
+
 
 /// LexTokenInternal - This implements a simple C family lexer.  It is an
 /// extremely performance critical piece of code.  This assumes that the buffer
@@ -2102,6 +2327,14 @@ LexNextToken:
       return PPCache->Lex(Result);
     }
 
+    // Check if we are performing code completion.
+    if (isCodeCompletionPoint(CurPtr-1)) {
+      // Return the code-completion token.
+      Result.startToken();
+      FormTokenWithChars(Result, CurPtr, tok::code_completion);
+      return;
+    }
+
     if (!isLexingRawMode())
       Diag(CurPtr-1, diag::null_in_file);
     Result.setFlag(Token::LeadingSpace);
@@ -2112,7 +2345,7 @@ LexNextToken:
       
   case 26:  // DOS & CP/M EOF: "^Z".
     // If we're in Microsoft extensions mode, treat this as end of file.
-    if (Features.Microsoft) {
+    if (Features.MicrosoftExt) {
       // Read the PP instance variable into an automatic variable, because
       // LexEndOfFile will often delete 'this'.
       Preprocessor *PPCache = PP;
@@ -2186,6 +2419,102 @@ LexNextToken:
     MIOpt.ReadToken();
     return LexNumericConstant(Result, CurPtr);
 
+  case 'u':   // Identifier (uber) or C++0x UTF-8 or UTF-16 string literal
+    // Notify MIOpt that we read a non-whitespace/non-comment token.
+    MIOpt.ReadToken();
+
+    if (Features.CPlusPlus0x) {
+      Char = getCharAndSize(CurPtr, SizeTmp);
+
+      // UTF-16 string literal
+      if (Char == '"')
+        return LexStringLiteral(Result, ConsumeChar(CurPtr, SizeTmp, Result),
+                                tok::utf16_string_literal);
+
+      // UTF-16 character constant
+      if (Char == '\'')
+        return LexCharConstant(Result, ConsumeChar(CurPtr, SizeTmp, Result),
+                               tok::utf16_char_constant);
+
+      // UTF-16 raw string literal
+      if (Char == 'R' && getCharAndSize(CurPtr + SizeTmp, SizeTmp2) == '"')
+        return LexRawStringLiteral(Result,
+                               ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                                           SizeTmp2, Result),
+                               tok::utf16_string_literal);
+
+      if (Char == '8') {
+        char Char2 = getCharAndSize(CurPtr + SizeTmp, SizeTmp2);
+
+        // UTF-8 string literal
+        if (Char2 == '"')
+          return LexStringLiteral(Result,
+                               ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                                           SizeTmp2, Result),
+                               tok::utf8_string_literal);
+
+        if (Char2 == 'R') {
+          unsigned SizeTmp3;
+          char Char3 = getCharAndSize(CurPtr + SizeTmp + SizeTmp2, SizeTmp3);
+          // UTF-8 raw string literal
+          if (Char3 == '"') {
+            return LexRawStringLiteral(Result,
+                   ConsumeChar(ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                                           SizeTmp2, Result),
+                               SizeTmp3, Result),
+                   tok::utf8_string_literal);
+          }
+        }
+      }
+    }
+
+    // treat u like the start of an identifier.
+    return LexIdentifier(Result, CurPtr);
+
+  case 'U':   // Identifier (Uber) or C++0x UTF-32 string literal
+    // Notify MIOpt that we read a non-whitespace/non-comment token.
+    MIOpt.ReadToken();
+
+    if (Features.CPlusPlus0x) {
+      Char = getCharAndSize(CurPtr, SizeTmp);
+
+      // UTF-32 string literal
+      if (Char == '"')
+        return LexStringLiteral(Result, ConsumeChar(CurPtr, SizeTmp, Result),
+                                tok::utf32_string_literal);
+
+      // UTF-32 character constant
+      if (Char == '\'')
+        return LexCharConstant(Result, ConsumeChar(CurPtr, SizeTmp, Result),
+                               tok::utf32_char_constant);
+
+      // UTF-32 raw string literal
+      if (Char == 'R' && getCharAndSize(CurPtr + SizeTmp, SizeTmp2) == '"')
+        return LexRawStringLiteral(Result,
+                               ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                                           SizeTmp2, Result),
+                               tok::utf32_string_literal);
+    }
+
+    // treat U like the start of an identifier.
+    return LexIdentifier(Result, CurPtr);
+
+  case 'R': // Identifier or C++0x raw string literal
+    // Notify MIOpt that we read a non-whitespace/non-comment token.
+    MIOpt.ReadToken();
+
+    if (Features.CPlusPlus0x) {
+      Char = getCharAndSize(CurPtr, SizeTmp);
+
+      if (Char == '"')
+        return LexRawStringLiteral(Result,
+                                   ConsumeChar(CurPtr, SizeTmp, Result),
+                                   tok::string_literal);
+    }
+
+    // treat R like the start of an identifier.
+    return LexIdentifier(Result, CurPtr);
+
   case 'L':   // Identifier (Loony) or wide literal (L'x' or L"xyz").
     // Notify MIOpt that we read a non-whitespace/non-comment token.
     MIOpt.ReadToken();
@@ -2194,21 +2523,30 @@ LexNextToken:
     // Wide string literal.
     if (Char == '"')
       return LexStringLiteral(Result, ConsumeChar(CurPtr, SizeTmp, Result),
-                              true);
+                              tok::wide_string_literal);
+
+    // Wide raw string literal.
+    if (Features.CPlusPlus0x && Char == 'R' &&
+        getCharAndSize(CurPtr + SizeTmp, SizeTmp2) == '"')
+      return LexRawStringLiteral(Result,
+                               ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                                           SizeTmp2, Result),
+                               tok::wide_string_literal);
 
     // Wide character constant.
     if (Char == '\'')
-      return LexCharConstant(Result, ConsumeChar(CurPtr, SizeTmp, Result));
+      return LexCharConstant(Result, ConsumeChar(CurPtr, SizeTmp, Result),
+                             tok::wide_char_constant);
     // FALL THROUGH, treating L like the start of an identifier.
 
   // C99 6.4.2: Identifiers.
   case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': case 'G':
   case 'H': case 'I': case 'J': case 'K':    /*'L'*/case 'M': case 'N':
-  case 'O': case 'P': case 'Q': case 'R': case 'S': case 'T': case 'U':
+  case 'O': case 'P': case 'Q':    /*'R'*/case 'S': case 'T':    /*'U'*/
   case 'V': case 'W': case 'X': case 'Y': case 'Z':
   case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': case 'g':
   case 'h': case 'i': case 'j': case 'k': case 'l': case 'm': case 'n':
-  case 'o': case 'p': case 'q': case 'r': case 's': case 't': case 'u':
+  case 'o': case 'p': case 'q': case 'r': case 's': case 't':    /*'u'*/
   case 'v': case 'w': case 'x': case 'y': case 'z':
   case '_':
     // Notify MIOpt that we read a non-whitespace/non-comment token.
@@ -2231,13 +2569,13 @@ LexNextToken:
   case '\'':
     // Notify MIOpt that we read a non-whitespace/non-comment token.
     MIOpt.ReadToken();
-    return LexCharConstant(Result, CurPtr);
+    return LexCharConstant(Result, CurPtr, tok::char_constant);
 
   // C99 6.4.5: String Literals.
   case '"':
     // Notify MIOpt that we read a non-whitespace/non-comment token.
     MIOpt.ReadToken();
-    return LexStringLiteral(Result, CurPtr, false);
+    return LexStringLiteral(Result, CurPtr, tok::string_literal);
 
   // C99 6.4.6: Punctuators.
   case '?':
@@ -2396,7 +2734,7 @@ LexNextToken:
         Kind = tok::hashhash;                          // '%:%:' -> '##'
         CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
                              SizeTmp2, Result);
-      } else if (Char == '@' && Features.Microsoft) {  // %:@ -> #@ -> Charize
+      } else if (Char == '@' && Features.MicrosoftExt) {// %:@ -> #@ -> Charize
         CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
         if (!isLexingRawMode())
           Diag(BufferPtr, diag::charize_microsoft_ext);
@@ -2447,6 +2785,10 @@ LexNextToken:
         // If this is actually a '<<<<<<<' version control conflict marker,
         // recognize it as such and recover nicely.
         goto LexNextToken;
+      } else if (After == '<' && HandleEndOfConflictMarker(CurPtr-1)) {
+        // If this is '<<<<' and we're in a Perforce-style conflict marker,
+        // ignore it.
+        goto LexNextToken;
       } else if (Features.CUDA && After == '<') {
         Kind = tok::lesslessless;
         CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
@@ -2470,6 +2812,8 @@ LexNextToken:
         char After = getCharAndSize(CurPtr + SizeTmp + SizeTmp2, SizeTmp3);
         if (After != ':' && After != '>') {
           Kind = tok::less;
+          if (!isLexingRawMode())
+            Diag(BufferPtr, diag::warn_cxx98_compat_less_colon_colon);
           break;
         }
       }
@@ -2494,6 +2838,10 @@ LexNextToken:
         CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
                              SizeTmp2, Result);
         Kind = tok::greatergreaterequal;
+      } else if (After == '>' && IsStartOfConflictMarker(CurPtr-1)) {
+        // If this is actually a '>>>>' conflict marker, recognize it as such
+        // and recover nicely.
+        goto LexNextToken;
       } else if (After == '>' && HandleEndOfConflictMarker(CurPtr-1)) {
         // If this is '>>>>>>>' and we're in a conflict marker, ignore it.
         goto LexNextToken;
@@ -2552,7 +2900,7 @@ LexNextToken:
   case '=':
     Char = getCharAndSize(CurPtr, SizeTmp);
     if (Char == '=') {
-      // If this is '=======' and we're in a conflict marker, ignore it.
+      // If this is '====' and we're in a conflict marker, ignore it.
       if (CurPtr[1] == '=' && HandleEndOfConflictMarker(CurPtr-1))
         goto LexNextToken;
       
@@ -2570,7 +2918,7 @@ LexNextToken:
     if (Char == '#') {
       Kind = tok::hashhash;
       CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
-    } else if (Char == '@' && Features.Microsoft) {  // #@ -> Charize
+    } else if (Char == '@' && Features.MicrosoftExt) {  // #@ -> Charize
       Kind = tok::hashat;
       if (!isLexingRawMode())
         Diag(BufferPtr, diag::charize_microsoft_ext);
diff --git a/lib/Lex/LiteralSupport.cpp b/lib/Lex/LiteralSupport.cpp
index 2c96c4d4ee24..70183fd1a0ea 100644
--- a/lib/Lex/LiteralSupport.cpp
+++ b/lib/Lex/LiteralSupport.cpp
@@ -16,8 +16,8 @@
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Lex/LexDiagnostic.h"
 #include "clang/Basic/TargetInfo.h"
-#include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/ErrorHandling.h"
 using namespace clang;
 
 /// HexDigitValue - Return the value of the specified hex digit, or -1 if it's
@@ -29,12 +29,31 @@ static int HexDigitValue(char C) {
   return -1;
 }
 
+static unsigned getCharWidth(tok::TokenKind kind, const TargetInfo &Target) {
+  switch (kind) {
+  default: llvm_unreachable("Unknown token type!");
+  case tok::char_constant:
+  case tok::string_literal:
+  case tok::utf8_string_literal:
+    return Target.getCharWidth();
+  case tok::wide_char_constant:
+  case tok::wide_string_literal:
+    return Target.getWCharWidth();
+  case tok::utf16_char_constant:
+  case tok::utf16_string_literal:
+    return Target.getChar16Width();
+  case tok::utf32_char_constant:
+  case tok::utf32_string_literal:
+    return Target.getChar32Width();
+  }
+}
+
 /// ProcessCharEscape - Parse a standard C escape sequence, which can occur in
 /// either a character or a string literal.
 static unsigned ProcessCharEscape(const char *&ThisTokBuf,
                                   const char *ThisTokEnd, bool &HadError,
-                                  FullSourceLoc Loc, bool IsWide,
-                                  Diagnostic *Diags, const TargetInfo &Target) {
+                                  FullSourceLoc Loc, unsigned CharWidth,
+                                  DiagnosticsEngine *Diags) {
   // Skip the '\' char.
   ++ThisTokBuf;
 
@@ -99,9 +118,6 @@ static unsigned ProcessCharEscape(const char *&ThisTokBuf,
     }
 
     // See if any bits will be truncated when evaluated as a character.
-    unsigned CharWidth =
-      IsWide ? Target.getWCharWidth() : Target.getCharWidth();
-
     if (CharWidth != 32 && (ResultChar >> CharWidth) != 0) {
       Overflow = true;
       ResultChar &= ~0U >> (32-CharWidth);
@@ -129,9 +145,6 @@ static unsigned ProcessCharEscape(const char *&ThisTokBuf,
              ThisTokBuf[0] >= '0' && ThisTokBuf[0] <= '7');
 
     // Check for overflow.  Reject '\777', but not L'\777'.
-    unsigned CharWidth =
-      IsWide ? Target.getWCharWidth() : Target.getCharWidth();
-
     if (CharWidth != 32 && (ResultChar >> CharWidth) != 0) {
       if (Diags)
         Diags->Report(Loc, diag::warn_octal_escape_too_large);
@@ -167,7 +180,7 @@ static unsigned ProcessCharEscape(const char *&ThisTokBuf,
 /// return the UTF32.
 static bool ProcessUCNEscape(const char *&ThisTokBuf, const char *ThisTokEnd,
                              uint32_t &UcnVal, unsigned short &UcnLen,
-                             FullSourceLoc Loc, Diagnostic *Diags, 
+                             FullSourceLoc Loc, DiagnosticsEngine *Diags, 
                              const LangOptions &Features) {
   if (!Features.CPlusPlus && !Features.C99 && Diags)
     Diags->Report(Loc, diag::warn_ucn_not_valid_in_c89);
@@ -220,7 +233,8 @@ static bool ProcessUCNEscape(const char *&ThisTokBuf, const char *ThisTokEnd,
 /// we will likely rework our support for UCN's.
 static void EncodeUCNEscape(const char *&ThisTokBuf, const char *ThisTokEnd,
                             char *&ResultBuf, bool &HadError,
-                            FullSourceLoc Loc, bool wide, Diagnostic *Diags, 
+                            FullSourceLoc Loc, unsigned CharByteWidth,
+                            DiagnosticsEngine *Diags,
                             const LangOptions &Features) {
   typedef uint32_t UTF32;
   UTF32 UcnVal = 0;
@@ -231,19 +245,22 @@ static void EncodeUCNEscape(const char *&ThisTokBuf, const char *ThisTokEnd,
     return;
   }
 
-  if (wide) {
-    (void)UcnLen;
-    assert((UcnLen== 4 || UcnLen== 8) && "only ucn length of 4 or 8 supported");
+  assert((CharByteWidth == 1 || CharByteWidth == 2 || CharByteWidth) &&
+         "only character widths of 1, 2, or 4 bytes supported");
 
-    if (!Features.ShortWChar) {
-      // Note: our internal rep of wide char tokens is always little-endian.
-      *ResultBuf++ = (UcnVal & 0x000000FF);
-      *ResultBuf++ = (UcnVal & 0x0000FF00) >> 8;
-      *ResultBuf++ = (UcnVal & 0x00FF0000) >> 16;
-      *ResultBuf++ = (UcnVal & 0xFF000000) >> 24;
-      return;
-    }
+  (void)UcnLen;
+  assert((UcnLen== 4 || UcnLen== 8) && "only ucn length of 4 or 8 supported");
 
+  if (CharByteWidth == 4) {
+    // Note: our internal rep of wide char tokens is always little-endian.
+    *ResultBuf++ = (UcnVal & 0x000000FF);
+    *ResultBuf++ = (UcnVal & 0x0000FF00) >> 8;
+    *ResultBuf++ = (UcnVal & 0x00FF0000) >> 16;
+    *ResultBuf++ = (UcnVal & 0xFF000000) >> 24;
+    return;
+  }
+
+  if (CharByteWidth == 2) {
     // Convert to UTF16.
     if (UcnVal < (UTF32)0xFFFF) {
       *ResultBuf++ = (UcnVal & 0x000000FF);
@@ -262,6 +279,9 @@ static void EncodeUCNEscape(const char *&ThisTokBuf, const char *ThisTokEnd,
     *ResultBuf++ = (surrogate2 & 0x0000FF00) >> 8;
     return;
   }
+
+  assert(CharByteWidth == 1 && "UTF-8 encoding is only for 1 byte characters");
+
   // Now that we've parsed/checked the UCN, we convert from UTF32->UTF8.
   // The conversion below was inspired by:
   //   http://www.unicode.org/Public/PROGRAMS/CVTUTF/ConvertUTF.c
@@ -371,7 +391,7 @@ NumericLiteralParser(const char *begin, const char *end,
       // Done.
     } else if (isxdigit(*s) && !(*s == 'e' || *s == 'E')) {
       PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-begin),
-              diag::err_invalid_decimal_digit) << llvm::StringRef(s, 1);
+              diag::err_invalid_decimal_digit) << StringRef(s, 1);
       hadError = true;
       return;
     } else if (*s == '.') {
@@ -434,7 +454,7 @@ NumericLiteralParser(const char *begin, const char *end,
       continue;  // Success.
     case 'i':
     case 'I':
-      if (PP.getLangOptions().Microsoft) {
+      if (PP.getLangOptions().MicrosoftExt) {
         if (isFPConstant || isLong || isLongLong) break;
 
         // Allow i8, i16, i32, i64, and i128.
@@ -498,7 +518,7 @@ NumericLiteralParser(const char *begin, const char *end,
     PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-begin),
             isFPConstant ? diag::err_invalid_suffix_float_constant :
                            diag::err_invalid_suffix_integer_constant)
-      << llvm::StringRef(SuffixBegin, ThisTokEnd-SuffixBegin);
+      << StringRef(SuffixBegin, ThisTokEnd-SuffixBegin);
     hadError = true;
     return;
   }
@@ -528,7 +548,7 @@ void NumericLiteralParser::ParseNumberStartingWithZero(SourceLocation TokLoc) {
     }
     // A binary exponent can appear with or with a '.'. If dotted, the
     // binary exponent is required.
-    if ((*s == 'p' || *s == 'P') && !PP.getLangOptions().CPlusPlus0x) {
+    if (*s == 'p' || *s == 'P') {
       const char *Exponent = s;
       s++;
       saw_exponent = true;
@@ -542,12 +562,7 @@ void NumericLiteralParser::ParseNumberStartingWithZero(SourceLocation TokLoc) {
       }
       s = first_non_digit;
 
-      // In C++0x, we cannot support hexadecmial floating literals because
-      // they conflict with user-defined literals, so we warn in previous
-      // versions of C++ by default.
-      if (PP.getLangOptions().CPlusPlus)
-        PP.Diag(TokLoc, diag::ext_hexconstant_cplusplus);
-      else if (!PP.getLangOptions().HexFloats)
+      if (!PP.getLangOptions().HexFloats)
         PP.Diag(TokLoc, diag::ext_hexconstant_invalid);
     } else if (saw_period) {
       PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-ThisTokBegin),
@@ -569,7 +584,7 @@ void NumericLiteralParser::ParseNumberStartingWithZero(SourceLocation TokLoc) {
       // Done.
     } else if (isxdigit(*s)) {
       PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-ThisTokBegin),
-              diag::err_invalid_binary_digit) << llvm::StringRef(s, 1);
+              diag::err_invalid_binary_digit) << StringRef(s, 1);
       hadError = true;
     }
     // Other suffixes will be diagnosed by the caller.
@@ -599,7 +614,7 @@ void NumericLiteralParser::ParseNumberStartingWithZero(SourceLocation TokLoc) {
   // the code is using an incorrect base.
   if (isxdigit(*s) && *s != 'e' && *s != 'E') {
     PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-ThisTokBegin),
-            diag::err_invalid_octal_digit) << llvm::StringRef(s, 1);
+            diag::err_invalid_octal_digit) << StringRef(s, 1);
     hadError = true;
     return;
   }
@@ -688,7 +703,6 @@ bool NumericLiteralParser::GetIntegerValue(llvm::APInt &Val) {
 llvm::APFloat::opStatus
 NumericLiteralParser::GetFloatValue(llvm::APFloat &Result) {
   using llvm::APFloat;
-  using llvm::StringRef;
 
   unsigned n = std::min(SuffixBegin - ThisTokBegin, ThisTokEnd - ThisTokBegin);
   return Result.convertFromString(StringRef(ThisTokBegin, n),
@@ -696,14 +710,51 @@ NumericLiteralParser::GetFloatValue(llvm::APFloat &Result) {
 }
 
 
+///       character-literal: [C++0x lex.ccon]
+///         ' c-char-sequence '
+///         u' c-char-sequence '
+///         U' c-char-sequence '
+///         L' c-char-sequence '
+///       c-char-sequence:
+///         c-char
+///         c-char-sequence c-char
+///       c-char:
+///         any member of the source character set except the single-quote ',
+///           backslash \, or new-line character
+///         escape-sequence
+///         universal-character-name
+///       escape-sequence: [C++0x lex.ccon]
+///         simple-escape-sequence
+///         octal-escape-sequence
+///         hexadecimal-escape-sequence
+///       simple-escape-sequence:
+///         one of \' \" \? \\ \a \b \f \n \r \t \v
+///       octal-escape-sequence:
+///         \ octal-digit
+///         \ octal-digit octal-digit
+///         \ octal-digit octal-digit octal-digit
+///       hexadecimal-escape-sequence:
+///         \x hexadecimal-digit
+///         hexadecimal-escape-sequence hexadecimal-digit
+///       universal-character-name:
+///         \u hex-quad
+///         \U hex-quad hex-quad
+///       hex-quad:
+///         hex-digit hex-digit hex-digit hex-digit
+///
 CharLiteralParser::CharLiteralParser(const char *begin, const char *end,
-                                     SourceLocation Loc, Preprocessor &PP) {
+                                     SourceLocation Loc, Preprocessor &PP,
+                                     tok::TokenKind kind) {
   // At this point we know that the character matches the regex "L?'.*'".
   HadError = false;
 
-  // Determine if this is a wide character.
-  IsWide = begin[0] == 'L';
-  if (IsWide) ++begin;
+  Kind = kind;
+
+  // Determine if this is a wide or UTF character.
+  if (Kind == tok::wide_char_constant || Kind == tok::utf16_char_constant ||
+      Kind == tok::utf32_char_constant) {
+    ++begin;
+  }
 
   // Skip over the entry quote.
   assert(begin[0] == '\'' && "Invalid token lexed");
@@ -730,8 +781,9 @@ CharLiteralParser::CharLiteralParser(const char *begin, const char *end,
 
       // Is this a Universal Character Name escape?
     if (begin[0] != '\\')     // If this is a normal character, consume it.
-      ResultChar = *begin++;
+      ResultChar = (unsigned char)*begin++;
     else {                    // Otherwise, this is an escape character.
+      unsigned CharWidth = getCharWidth(Kind, PP.getTargetInfo());
       // Check for UCN.
       if (begin[1] == 'u' || begin[1] == 'U') {
         uint32_t utf32 = 0;
@@ -742,19 +794,22 @@ CharLiteralParser::CharLiteralParser(const char *begin, const char *end,
           HadError = 1;
         }
         ResultChar = utf32;
+        if (CharWidth != 32 && (ResultChar >> CharWidth) != 0) {
+          PP.Diag(Loc, diag::warn_ucn_escape_too_large);
+          ResultChar &= ~0U >> (32-CharWidth);
+        }
       } else {
         // Otherwise, this is a non-UCN escape character.  Process it.
         ResultChar = ProcessCharEscape(begin, end, HadError,
                                        FullSourceLoc(Loc,PP.getSourceManager()),
-                                       IsWide,
-                                       &PP.getDiagnostics(), PP.getTargetInfo());
+                                       CharWidth, &PP.getDiagnostics());
       }
     }
 
     // If this is a multi-character constant (e.g. 'abc'), handle it.  These are
     // implementation defined (C99 6.4.4.4p10).
     if (NumCharsSoFar) {
-      if (IsWide) {
+      if (!isAscii()) {
         // Emulate GCC's (unintentional?) behavior: L'ab' -> L'b'.
         LitVal = 0;
       } else {
@@ -776,8 +831,8 @@ CharLiteralParser::CharLiteralParser(const char *begin, const char *end,
   if (NumCharsSoFar > 1) {
     // Warn about discarding the top bits for multi-char wide-character
     // constants (L'abcd').
-    if (IsWide)
-      PP.Diag(Loc, diag::warn_extraneous_wide_char_constant);
+    if (!isAscii())
+      PP.Diag(Loc, diag::warn_extraneous_char_constant);
     else if (NumCharsSoFar != 4)
       PP.Diag(Loc, diag::ext_multichar_character_literal);
     else
@@ -789,47 +844,62 @@ CharLiteralParser::CharLiteralParser(const char *begin, const char *end,
   // Transfer the value from APInt to uint64_t
   Value = LitVal.getZExtValue();
 
-  if (IsWide && PP.getLangOptions().ShortWChar && Value > 0xFFFF)
-    PP.Diag(Loc, diag::warn_ucn_escape_too_large);
-
   // If this is a single narrow character, sign extend it (e.g. '\xFF' is "-1")
   // if 'char' is signed for this target (C99 6.4.4.4p10).  Note that multiple
   // character constants are not sign extended in the this implementation:
   // '\xFF\xFF' = 65536 and '\x0\xFF' = 255, which matches GCC.
-  if (!IsWide && NumCharsSoFar == 1 && (Value & 128) &&
+  if (isAscii() && NumCharsSoFar == 1 && (Value & 128) &&
       PP.getLangOptions().CharIsSigned)
     Value = (signed char)Value;
 }
 
 
-///       string-literal: [C99 6.4.5]
-///          " [s-char-sequence] "
-///         L" [s-char-sequence] "
+///       string-literal: [C++0x lex.string]
+///         encoding-prefix " [s-char-sequence] "
+///         encoding-prefix R raw-string
+///       encoding-prefix:
+///         u8
+///         u
+///         U
+///         L
 ///       s-char-sequence:
 ///         s-char
 ///         s-char-sequence s-char
 ///       s-char:
-///         any source character except the double quote ",
-///           backslash \, or newline character
-///         escape-character
-///         universal-character-name
-///       escape-character: [C99 6.4.4.4]
-///         \ escape-code
+///         any member of the source character set except the double-quote ",
+///           backslash \, or new-line character
+///         escape-sequence
 ///         universal-character-name
-///       escape-code:
-///         character-escape-code
-///         octal-escape-code
-///         hex-escape-code
-///       character-escape-code: one of
-///         n t b r f v a
-///         \ ' " ?
-///       octal-escape-code:
-///         octal-digit
-///         octal-digit octal-digit
-///         octal-digit octal-digit octal-digit
-///       hex-escape-code:
-///         x hex-digit
-///         hex-escape-code hex-digit
+///       raw-string:
+///         " d-char-sequence ( r-char-sequence ) d-char-sequence "
+///       r-char-sequence:
+///         r-char
+///         r-char-sequence r-char
+///       r-char:
+///         any member of the source character set, except a right parenthesis )
+///           followed by the initial d-char-sequence (which may be empty)
+///           followed by a double quote ".
+///       d-char-sequence:
+///         d-char
+///         d-char-sequence d-char
+///       d-char:
+///         any member of the basic source character set except:
+///           space, the left parenthesis (, the right parenthesis ),
+///           the backslash \, and the control characters representing horizontal
+///           tab, vertical tab, form feed, and newline.
+///       escape-sequence: [C++0x lex.ccon]
+///         simple-escape-sequence
+///         octal-escape-sequence
+///         hexadecimal-escape-sequence
+///       simple-escape-sequence:
+///         one of \' \" \? \\ \a \b \f \n \r \t \v
+///       octal-escape-sequence:
+///         \ octal-digit
+///         \ octal-digit octal-digit
+///         \ octal-digit octal-digit octal-digit
+///       hexadecimal-escape-sequence:
+///         \x hexadecimal-digit
+///         hexadecimal-escape-sequence hexadecimal-digit
 ///       universal-character-name:
 ///         \u hex-quad
 ///         \U hex-quad hex-quad
@@ -841,8 +911,8 @@ StringLiteralParser(const Token *StringToks, unsigned NumStringToks,
                     Preprocessor &PP, bool Complain)
   : SM(PP.getSourceManager()), Features(PP.getLangOptions()),
     Target(PP.getTargetInfo()), Diags(Complain ? &PP.getDiagnostics() : 0),
-    MaxTokenLength(0), SizeBound(0), wchar_tByteWidth(0),
-    ResultPtr(ResultBuf.data()), hadError(false), AnyWide(false), Pascal(false) {
+    MaxTokenLength(0), SizeBound(0), CharByteWidth(0), Kind(tok::unknown),
+    ResultPtr(ResultBuf.data()), hadError(false), Pascal(false) {
   init(StringToks, NumStringToks);
 }
 
@@ -862,7 +932,7 @@ void StringLiteralParser::init(const Token *StringToks, unsigned NumStringToks){
   MaxTokenLength = StringToks[0].getLength();
   assert(StringToks[0].getLength() >= 2 && "literal token is invalid!");
   SizeBound = StringToks[0].getLength()-2;  // -2 for "".
-  AnyWide = StringToks[0].is(tok::wide_string_literal);
+  Kind = StringToks[0].getKind();
 
   hadError = false;
 
@@ -883,8 +953,18 @@ void StringLiteralParser::init(const Token *StringToks, unsigned NumStringToks){
     if (StringToks[i].getLength() > MaxTokenLength)
       MaxTokenLength = StringToks[i].getLength();
 
-    // Remember if we see any wide strings.
-    AnyWide |= StringToks[i].is(tok::wide_string_literal);
+    // Remember if we see any wide or utf-8/16/32 strings.
+    // Also check for illegal concatenations.
+    if (StringToks[i].isNot(Kind) && StringToks[i].isNot(tok::string_literal)) {
+      if (isAscii()) {
+        Kind = StringToks[i].getKind();
+      } else {
+        if (Diags)
+          Diags->Report(FullSourceLoc(StringToks[i].getLocation(), SM),
+                        diag::err_unsupported_string_concat);
+        hadError = true;
+      }
+    }
   }
 
   // Include space for the null terminator.
@@ -892,19 +972,14 @@ void StringLiteralParser::init(const Token *StringToks, unsigned NumStringToks){
 
   // TODO: K&R warning: "traditional C rejects string constant concatenation"
 
-  // Get the width in bytes of wchar_t.  If no wchar_t strings are used, do not
-  // query the target.  As such, wchar_tByteWidth is only valid if AnyWide=true.
-  wchar_tByteWidth = ~0U;
-  if (AnyWide) {
-    wchar_tByteWidth = Target.getWCharWidth();
-    assert((wchar_tByteWidth & 7) == 0 && "Assumes wchar_t is byte multiple!");
-    wchar_tByteWidth /= 8;
-  }
+  // Get the width in bytes of char/wchar_t/char16_t/char32_t
+  CharByteWidth = getCharWidth(Kind, Target);
+  assert((CharByteWidth & 7) == 0 && "Assumes character size is byte multiple");
+  CharByteWidth /= 8;
 
   // The output buffer size needs to be large enough to hold wide characters.
   // This is a worst-case assumption which basically corresponds to L"" "long".
-  if (AnyWide)
-    SizeBound *= wchar_tByteWidth;
+  SizeBound *= CharByteWidth;
 
   // Size the temporary buffer to hold the result string data.
   ResultBuf.resize(SizeBound);
@@ -929,78 +1004,82 @@ void StringLiteralParser::init(const Token *StringToks, unsigned NumStringToks){
       Lexer::getSpelling(StringToks[i], ThisTokBuf, SM, Features,
                          &StringInvalid);
     if (StringInvalid) {
-      hadError = 1;
+      hadError = true;
       continue;
     }
 
     const char *ThisTokEnd = ThisTokBuf+ThisTokLen-1;  // Skip end quote.
-    bool wide = false;
     // TODO: Input character set mapping support.
 
-    // Skip L marker for wide strings.
-    if (ThisTokBuf[0] == 'L') {
-      wide = true;
+    // Skip marker for wide or unicode strings.
+    if (ThisTokBuf[0] == 'L' || ThisTokBuf[0] == 'u' || ThisTokBuf[0] == 'U') {
       ++ThisTokBuf;
+      // Skip 8 of u8 marker for utf8 strings.
+      if (ThisTokBuf[0] == '8')
+        ++ThisTokBuf;
     }
 
-    assert(ThisTokBuf[0] == '"' && "Expected quote, lexer broken?");
-    ++ThisTokBuf;
-
-    // Check if this is a pascal string
-    if (Features.PascalStrings && ThisTokBuf + 1 != ThisTokEnd &&
-        ThisTokBuf[0] == '\\' && ThisTokBuf[1] == 'p') {
+    // Check for raw string
+    if (ThisTokBuf[0] == 'R') {
+      ThisTokBuf += 2; // skip R"
 
-      // If the \p sequence is found in the first token, we have a pascal string
-      // Otherwise, if we already have a pascal string, ignore the first \p
-      if (i == 0) {
+      const char *Prefix = ThisTokBuf;
+      while (ThisTokBuf[0] != '(')
         ++ThisTokBuf;
-        Pascal = true;
-      } else if (Pascal)
-        ThisTokBuf += 2;
-    }
+      ++ThisTokBuf; // skip '('
+
+      // remove same number of characters from the end
+      if (ThisTokEnd >= ThisTokBuf + (ThisTokBuf - Prefix))
+        ThisTokEnd -= (ThisTokBuf - Prefix);
+
+      // Copy the string over
+      CopyStringFragment(StringRef(ThisTokBuf, ThisTokEnd - ThisTokBuf));
+    } else {
+      assert(ThisTokBuf[0] == '"' && "Expected quote, lexer broken?");
+      ++ThisTokBuf; // skip "
+
+      // Check if this is a pascal string
+      if (Features.PascalStrings && ThisTokBuf + 1 != ThisTokEnd &&
+          ThisTokBuf[0] == '\\' && ThisTokBuf[1] == 'p') {
 
-    while (ThisTokBuf != ThisTokEnd) {
-      // Is this a span of non-escape characters?
-      if (ThisTokBuf[0] != '\\') {
-        const char *InStart = ThisTokBuf;
-        do {
+        // If the \p sequence is found in the first token, we have a pascal string
+        // Otherwise, if we already have a pascal string, ignore the first \p
+        if (i == 0) {
           ++ThisTokBuf;
-        } while (ThisTokBuf != ThisTokEnd && ThisTokBuf[0] != '\\');
-
-        // Copy the character span over.
-        unsigned Len = ThisTokBuf-InStart;
-        if (!AnyWide) {
-          memcpy(ResultPtr, InStart, Len);
-          ResultPtr += Len;
-        } else {
-          // Note: our internal rep of wide char tokens is always little-endian.
-          for (; Len; --Len, ++InStart) {
-            *ResultPtr++ = InStart[0];
-            // Add zeros at the end.
-            for (unsigned i = 1, e = wchar_tByteWidth; i != e; ++i)
-              *ResultPtr++ = 0;
-          }
-        }
-        continue;
-      }
-      // Is this a Universal Character Name escape?
-      if (ThisTokBuf[1] == 'u' || ThisTokBuf[1] == 'U') {
-        EncodeUCNEscape(ThisTokBuf, ThisTokEnd, ResultPtr,
-                        hadError, FullSourceLoc(StringToks[i].getLocation(),SM),
-                        wide, Diags, Features);
-        continue;
+          Pascal = true;
+        } else if (Pascal)
+          ThisTokBuf += 2;
       }
-      // Otherwise, this is a non-UCN escape character.  Process it.
-      unsigned ResultChar =
-        ProcessCharEscape(ThisTokBuf, ThisTokEnd, hadError,
-                          FullSourceLoc(StringToks[i].getLocation(), SM),
-                          AnyWide, Diags, Target);
 
-      // Note: our internal rep of wide char tokens is always little-endian.
-      *ResultPtr++ = ResultChar & 0xFF;
+      while (ThisTokBuf != ThisTokEnd) {
+        // Is this a span of non-escape characters?
+        if (ThisTokBuf[0] != '\\') {
+          const char *InStart = ThisTokBuf;
+          do {
+            ++ThisTokBuf;
+          } while (ThisTokBuf != ThisTokEnd && ThisTokBuf[0] != '\\');
+
+          // Copy the character span over.
+          CopyStringFragment(StringRef(InStart, ThisTokBuf - InStart));
+          continue;
+        }
+        // Is this a Universal Character Name escape?
+        if (ThisTokBuf[1] == 'u' || ThisTokBuf[1] == 'U') {
+          EncodeUCNEscape(ThisTokBuf, ThisTokEnd, ResultPtr,
+                          hadError, FullSourceLoc(StringToks[i].getLocation(),SM),
+                          CharByteWidth, Diags, Features);
+          continue;
+        }
+        // Otherwise, this is a non-UCN escape character.  Process it.
+        unsigned ResultChar =
+          ProcessCharEscape(ThisTokBuf, ThisTokEnd, hadError,
+                            FullSourceLoc(StringToks[i].getLocation(), SM),
+                            CharByteWidth*8, Diags);
+
+        // Note: our internal rep of wide char tokens is always little-endian.
+        *ResultPtr++ = ResultChar & 0xFF;
 
-      if (AnyWide) {
-        for (unsigned i = 1, e = wchar_tByteWidth; i != e; ++i)
+        for (unsigned i = 1, e = CharByteWidth; i != e; ++i)
           *ResultPtr++ = ResultChar >> i*8;
       }
     }
@@ -1008,8 +1087,7 @@ void StringLiteralParser::init(const Token *StringToks, unsigned NumStringToks){
 
   if (Pascal) {
     ResultBuf[0] = ResultPtr-&ResultBuf[0]-1;
-    if (AnyWide)
-      ResultBuf[0] /= wchar_tByteWidth;
+    ResultBuf[0] /= CharByteWidth;
 
     // Verify that pascal strings aren't too large.
     if (GetStringLength() > 256) {
@@ -1018,7 +1096,7 @@ void StringLiteralParser::init(const Token *StringToks, unsigned NumStringToks){
                       diag::err_pascal_string_too_long)
           << SourceRange(StringToks[0].getLocation(),
                          StringToks[NumStringToks-1].getLocation());
-      hadError = 1;
+      hadError = true;
       return;
     }
   } else if (Diags) {
@@ -1036,6 +1114,25 @@ void StringLiteralParser::init(const Token *StringToks, unsigned NumStringToks){
 }
 
 
+/// copyStringFragment - This function copies from Start to End into ResultPtr.
+/// Performs widening for multi-byte characters.
+void StringLiteralParser::CopyStringFragment(StringRef Fragment) {
+  // Copy the character span over.
+  if (CharByteWidth == 1) {
+    memcpy(ResultPtr, Fragment.data(), Fragment.size());
+    ResultPtr += Fragment.size();
+  } else {
+    // Note: our internal rep of wide char tokens is always little-endian.
+    for (StringRef::iterator I=Fragment.begin(), E=Fragment.end(); I!=E; ++I) {
+      *ResultPtr++ = *I;
+      // Add zeros at the end.
+      for (unsigned i = 1, e = CharByteWidth; i != e; ++i)
+        *ResultPtr++ = 0;
+    }
+  }
+}
+
+
 /// getOffsetOfStringByte - This function returns the offset of the
 /// specified byte of the string data represented by Token.  This handles
 /// advancing over escape sequences in the string.
@@ -1052,7 +1149,8 @@ unsigned StringLiteralParser::getOffsetOfStringByte(const Token &Tok,
   if (StringInvalid)
     return 0;
 
-  assert(SpellingPtr[0] != 'L' && "Doesn't handle wide strings yet");
+  assert(SpellingPtr[0] != 'L' && SpellingPtr[0] != 'u' &&
+         SpellingPtr[0] != 'U' && "Doesn't handle wide or utf strings yet");
 
 
   const char *SpellingStart = SpellingPtr;
@@ -1077,7 +1175,7 @@ unsigned StringLiteralParser::getOffsetOfStringByte(const Token &Tok,
     bool HadError = false;
     ProcessCharEscape(SpellingPtr, SpellingEnd, HadError,
                       FullSourceLoc(Tok.getLocation(), SM),
-                      false, Diags, Target);
+                      CharByteWidth*8, Diags);
     assert(!HadError && "This method isn't valid on erroneous strings");
     --ByteNo;
   }
diff --git a/lib/Lex/MacroArgs.cpp b/lib/Lex/MacroArgs.cpp
index 968c15e3c27b..1846d1c05e30 100644
--- a/lib/Lex/MacroArgs.cpp
+++ b/lib/Lex/MacroArgs.cpp
@@ -15,13 +15,15 @@
 #include "clang/Lex/MacroInfo.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Lex/LexDiagnostic.h"
+
+#include <algorithm>
+
 using namespace clang;
 
 /// MacroArgs ctor function - This destroys the vector passed in.
 MacroArgs *MacroArgs::create(const MacroInfo *MI,
-                             const Token *UnexpArgTokens,
-                             unsigned NumToks, bool VarargsElided,
-                             Preprocessor &PP) {
+                             llvm::ArrayRef<Token> UnexpArgTokens,
+                             bool VarargsElided, Preprocessor &PP) {
   assert(MI->isFunctionLike() &&
          "Can't have args for an object-like macro!");
   MacroArgs **ResultEnt = 0;
@@ -31,12 +33,12 @@ MacroArgs *MacroArgs::create(const MacroInfo *MI,
   // free list.  If so, reuse it.
   for (MacroArgs **Entry = &PP.MacroArgCache; *Entry;
        Entry = &(*Entry)->ArgCache)
-    if ((*Entry)->NumUnexpArgTokens >= NumToks &&
+    if ((*Entry)->NumUnexpArgTokens >= UnexpArgTokens.size() &&
         (*Entry)->NumUnexpArgTokens < ClosestMatch) {
       ResultEnt = Entry;
       
       // If we have an exact match, use it.
-      if ((*Entry)->NumUnexpArgTokens == NumToks)
+      if ((*Entry)->NumUnexpArgTokens == UnexpArgTokens.size())
         break;
       // Otherwise, use the best fit.
       ClosestMatch = (*Entry)->NumUnexpArgTokens;
@@ -45,21 +47,22 @@ MacroArgs *MacroArgs::create(const MacroInfo *MI,
   MacroArgs *Result;
   if (ResultEnt == 0) {
     // Allocate memory for a MacroArgs object with the lexer tokens at the end.
-    Result = (MacroArgs*)malloc(sizeof(MacroArgs) + NumToks*sizeof(Token));
+    Result = (MacroArgs*)malloc(sizeof(MacroArgs) + 
+                                UnexpArgTokens.size() * sizeof(Token));
     // Construct the MacroArgs object.
-    new (Result) MacroArgs(NumToks, VarargsElided);
+    new (Result) MacroArgs(UnexpArgTokens.size(), VarargsElided);
   } else {
     Result = *ResultEnt;
     // Unlink this node from the preprocessors singly linked list.
     *ResultEnt = Result->ArgCache;
-    Result->NumUnexpArgTokens = NumToks;
+    Result->NumUnexpArgTokens = UnexpArgTokens.size();
     Result->VarargsElided = VarargsElided;
   }
 
   // Copy the actual unexpanded tokens to immediately after the result ptr.
-  if (NumToks)
-    memcpy(const_cast<Token*>(Result->getUnexpArgument(0)),
-           UnexpArgTokens, NumToks*sizeof(Token));
+  if (!UnexpArgTokens.empty())
+    std::copy(UnexpArgTokens.begin(), UnexpArgTokens.end(), 
+              const_cast<Token*>(Result->getUnexpArgument(0)));
 
   return Result;
 }
@@ -186,7 +189,8 @@ MacroArgs::getPreExpArgument(unsigned Arg, const MacroInfo *MI,
 ///
 Token MacroArgs::StringifyArgument(const Token *ArgToks,
                                    Preprocessor &PP, bool Charify,
-                                   SourceLocation hashInstLoc) {
+                                   SourceLocation ExpansionLocStart,
+                                   SourceLocation ExpansionLocEnd) {
   Token Tok;
   Tok.startToken();
   Tok.setKind(Charify ? tok::char_constant : tok::string_literal);
@@ -208,13 +212,21 @@ Token MacroArgs::StringifyArgument(const Token *ArgToks,
     // by 6.10.3.2p2.
     if (Tok.is(tok::string_literal) ||       // "foo"
         Tok.is(tok::wide_string_literal) ||  // L"foo"
-        Tok.is(tok::char_constant)) {        // 'x' and L'x'.
+        Tok.is(tok::utf8_string_literal) ||  // u8"foo"
+        Tok.is(tok::utf16_string_literal) || // u"foo"
+        Tok.is(tok::utf32_string_literal) || // U"foo"
+        Tok.is(tok::char_constant) ||        // 'x'
+        Tok.is(tok::wide_char_constant) ||   // L'x'.
+        Tok.is(tok::utf16_char_constant) ||  // u'x'.
+        Tok.is(tok::utf32_char_constant)) {  // U'x'.
       bool Invalid = false;
       std::string TokStr = PP.getSpelling(Tok, &Invalid);
       if (!Invalid) {
         std::string Str = Lexer::Stringify(TokStr);
         Result.append(Str.begin(), Str.end());
       }
+    } else if (Tok.is(tok::code_completion)) {
+      PP.CodeCompleteNaturalLanguage();
     } else {
       // Otherwise, just append the token.  Do some gymnastics to get the token
       // in place and avoid copies where possible.
@@ -274,7 +286,8 @@ Token MacroArgs::StringifyArgument(const Token *ArgToks,
     }
   }
 
-  PP.CreateString(&Result[0], Result.size(), Tok, hashInstLoc);
+  PP.CreateString(&Result[0], Result.size(), Tok,
+                  ExpansionLocStart, ExpansionLocEnd);
   return Tok;
 }
 
@@ -282,7 +295,8 @@ Token MacroArgs::StringifyArgument(const Token *ArgToks,
 /// that has been 'stringified' as required by the # operator.
 const Token &MacroArgs::getStringifiedArgument(unsigned ArgNo,
                                                Preprocessor &PP,
-                                               SourceLocation hashInstLoc) {
+                                               SourceLocation ExpansionLocStart,
+                                               SourceLocation ExpansionLocEnd) {
   assert(ArgNo < NumUnexpArgTokens && "Invalid argument number!");
   if (StringifiedArgs.empty()) {
     StringifiedArgs.resize(getNumArguments());
@@ -291,6 +305,8 @@ const Token &MacroArgs::getStringifiedArgument(unsigned ArgNo,
   }
   if (StringifiedArgs[ArgNo].isNot(tok::string_literal))
     StringifiedArgs[ArgNo] = StringifyArgument(getUnexpArgument(ArgNo), PP,
-                                               /*Charify=*/false, hashInstLoc);
+                                               /*Charify=*/false,
+                                               ExpansionLocStart,
+                                               ExpansionLocEnd);
   return StringifiedArgs[ArgNo];
 }
diff --git a/lib/Lex/MacroArgs.h b/lib/Lex/MacroArgs.h
index a962dacf7c93..cf86d710adb7 100644
--- a/lib/Lex/MacroArgs.h
+++ b/lib/Lex/MacroArgs.h
@@ -14,6 +14,8 @@
 #ifndef LLVM_CLANG_MACROARGS_H
 #define LLVM_CLANG_MACROARGS_H
 
+#include "llvm/ADT/ArrayRef.h"
+
 #include <vector>
 
 namespace clang {
@@ -58,9 +60,8 @@ public:
   /// MacroArgs ctor function - Create a new MacroArgs object with the specified
   /// macro and argument info.
   static MacroArgs *create(const MacroInfo *MI,
-                           const Token *UnexpArgTokens,
-                           unsigned NumArgTokens, bool VarargsElided,
-                           Preprocessor &PP);
+                           llvm::ArrayRef<Token> UnexpArgTokens,
+                           bool VarargsElided, Preprocessor &PP);
 
   /// destroy - Destroy and deallocate the memory for this object.
   ///
@@ -88,7 +89,8 @@ public:
   /// getStringifiedArgument - Compute, cache, and return the specified argument
   /// that has been 'stringified' as required by the # operator.
   const Token &getStringifiedArgument(unsigned ArgNo, Preprocessor &PP,
-                                      SourceLocation hashInstLoc);
+                                      SourceLocation ExpansionLocStart,
+                                      SourceLocation ExpansionLocEnd);
 
   /// getNumArguments - Return the number of arguments passed into this macro
   /// invocation.
@@ -109,7 +111,8 @@ public:
   ///
   static Token StringifyArgument(const Token *ArgToks,
                                  Preprocessor &PP, bool Charify,
-                                 SourceLocation hashInstLoc);
+                                 SourceLocation ExpansionLocStart,
+                                 SourceLocation ExpansionLocEnd);
   
   
   /// deallocate - This should only be called by the Preprocessor when managing
diff --git a/lib/Lex/MacroInfo.cpp b/lib/Lex/MacroInfo.cpp
index 0a16a2567219..5a7af5639830 100644
--- a/lib/Lex/MacroInfo.cpp
+++ b/lib/Lex/MacroInfo.cpp
@@ -21,6 +21,7 @@ MacroInfo::MacroInfo(SourceLocation DefLoc) : Location(DefLoc) {
   IsGNUVarargs = false;
   IsBuiltinMacro = false;
   IsFromAST = false;
+  ChangedAfterLoad = false;
   IsDisabled = false;
   IsUsed = false;
   IsAllowRedefinitionsWithoutWarning = false;
@@ -40,6 +41,7 @@ MacroInfo::MacroInfo(const MacroInfo &MI, llvm::BumpPtrAllocator &PPAllocator) {
   IsGNUVarargs = MI.IsGNUVarargs;
   IsBuiltinMacro = MI.IsBuiltinMacro;
   IsFromAST = MI.IsFromAST;
+  ChangedAfterLoad = MI.ChangedAfterLoad;
   IsDisabled = MI.IsDisabled;
   IsUsed = MI.IsUsed;
   IsAllowRedefinitionsWithoutWarning = MI.IsAllowRedefinitionsWithoutWarning;
@@ -68,9 +70,9 @@ unsigned MacroInfo::getDefinitionLengthSlow(SourceManager &SM) const {
   assert((macroEnd.isFileID() || lastToken.is(tok::comment)) &&
          "Macro defined in macro?");
   std::pair<FileID, unsigned>
-      startInfo = SM.getDecomposedInstantiationLoc(macroStart);
+      startInfo = SM.getDecomposedExpansionLoc(macroStart);
   std::pair<FileID, unsigned>
-      endInfo = SM.getDecomposedInstantiationLoc(macroEnd);
+      endInfo = SM.getDecomposedExpansionLoc(macroEnd);
   assert(startInfo.first == endInfo.first &&
          "Macro definition spanning multiple FileIDs ?");
   assert(startInfo.second <= endInfo.second);
diff --git a/lib/Lex/PPCaching.cpp b/lib/Lex/PPCaching.cpp
index 33106591c3ba..986341b98668 100644
--- a/lib/Lex/PPCaching.cpp
+++ b/lib/Lex/PPCaching.cpp
@@ -74,6 +74,8 @@ void Preprocessor::EnterCachingLexMode() {
     return;
 
   PushIncludeMacroStack();
+  if (CurLexerKind != CLK_LexAfterModuleImport)
+    CurLexerKind = CLK_CachingLexer;
 }
 
 
diff --git a/lib/Lex/PPDirectives.cpp b/lib/Lex/PPDirectives.cpp
index 4af5fabe5c80..de50c750e4d6 100644
--- a/lib/Lex/PPDirectives.cpp
+++ b/lib/Lex/PPDirectives.cpp
@@ -17,6 +17,7 @@
 #include "clang/Lex/MacroInfo.h"
 #include "clang/Lex/LexDiagnostic.h"
 #include "clang/Lex/CodeCompletionHandler.h"
+#include "clang/Lex/ModuleLoader.h"
 #include "clang/Lex/Pragma.h"
 #include "clang/Basic/FileManager.h"
 #include "clang/Basic/SourceManager.h"
@@ -102,8 +103,8 @@ void Preprocessor::ReadMacroName(Token &MacroNameTok, char isDefineUndef) {
   if (MacroNameTok.is(tok::code_completion)) {
     if (CodeComplete)
       CodeComplete->CodeCompleteMacroName(isDefineUndef == 1);
+    setCodeCompletionReached();
     LexUnexpandedToken(MacroNameTok);
-    return;
   }
   
   // Missing macro name?
@@ -192,7 +193,8 @@ void Preprocessor::CheckEndOfDirective(const char *DirType, bool EnableMacros) {
 /// the first valid token.
 void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc,
                                                 bool FoundNonSkipPortion,
-                                                bool FoundElse) {
+                                                bool FoundElse,
+                                                SourceLocation ElseLoc) {
   ++NumSkipped;
   assert(CurTokenLexer == 0 && CurPPLexer && "Lexing a macro, not a file?");
 
@@ -214,6 +216,7 @@ void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc,
     if (Tok.is(tok::code_completion)) {
       if (CodeComplete)
         CodeComplete->CodeCompleteInConditionalExclusion();
+      setCodeCompletionReached();
       continue;
     }
     
@@ -222,7 +225,7 @@ void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc,
       // Emit errors for each unterminated conditional on the stack, including
       // the current one.
       while (!CurPPLexer->ConditionalStack.empty()) {
-        if (!isCodeCompletionFile(Tok.getLocation()))
+        if (CurLexer->getFileLoc() != CodeCompletionFileLoc)
           Diag(CurPPLexer->ConditionalStack.back().IfLoc,
                diag::err_pp_unterminated_conditional);
         CurPPLexer->ConditionalStack.pop_back();
@@ -275,9 +278,9 @@ void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc,
     // that we can't use Tok.getIdentifierInfo() because its lookup is disabled
     // when skipping.
     char DirectiveBuf[20];
-    llvm::StringRef Directive;
+    StringRef Directive;
     if (!Tok.needsCleaning() && Tok.getLength() < 20) {
-      Directive = llvm::StringRef(RawCharData, Tok.getLength());
+      Directive = StringRef(RawCharData, Tok.getLength());
     } else {
       std::string DirectiveStr = getSpelling(Tok);
       unsigned IdLen = DirectiveStr.size();
@@ -288,11 +291,11 @@ void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc,
         continue;
       }
       memcpy(DirectiveBuf, &DirectiveStr[0], IdLen);
-      Directive = llvm::StringRef(DirectiveBuf, IdLen);
+      Directive = StringRef(DirectiveBuf, IdLen);
     }
 
     if (Directive.startswith("if")) {
-      llvm::StringRef Sub = Directive.substr(2);
+      StringRef Sub = Directive.substr(2);
       if (Sub.empty() ||   // "if"
           Sub == "def" ||   // "ifdef"
           Sub == "ndef") {  // "ifndef"
@@ -307,7 +310,7 @@ void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc,
           Callbacks->Endif();
       }
     } else if (Directive[0] == 'e') {
-      llvm::StringRef Sub = Directive.substr(1);
+      StringRef Sub = Directive.substr(1);
       if (Sub == "ndif") {  // "endif"
         CheckEndOfDirective("endif");
         PPConditionalInfo CondInfo;
@@ -387,6 +390,11 @@ void Preprocessor::SkipExcludedConditionalBlock(SourceLocation IfTokenLoc,
   // of the file, just stop skipping and return to lexing whatever came after
   // the #if block.
   CurPPLexer->LexingRawMode = false;
+
+  if (Callbacks) {
+    SourceLocation BeginLoc = ElseLoc.isValid() ? ElseLoc : IfTokenLoc;
+    Callbacks->SourceRangeSkipped(SourceRange(BeginLoc, Tok.getLocation()));
+  }
 }
 
 void Preprocessor::PTHSkipExcludedConditionalBlock() {
@@ -472,12 +480,13 @@ void Preprocessor::PTHSkipExcludedConditionalBlock() {
 /// return null on failure.  isAngled indicates whether the file reference is
 /// for system #include's or not (i.e. using <> instead of "").
 const FileEntry *Preprocessor::LookupFile(
-    llvm::StringRef Filename,
+    StringRef Filename,
     bool isAngled,
     const DirectoryLookup *FromDir,
     const DirectoryLookup *&CurDir,
-    llvm::SmallVectorImpl<char> *SearchPath,
-    llvm::SmallVectorImpl<char> *RelativePath) {
+    SmallVectorImpl<char> *SearchPath,
+    SmallVectorImpl<char> *RelativePath,
+    StringRef *SuggestedModule) {
   // If the header lookup mechanism may be relative to the current file, pass in
   // info about where the current file is.
   const FileEntry *CurFileEnt = 0;
@@ -501,12 +510,13 @@ const FileEntry *Preprocessor::LookupFile(
   CurDir = CurDirLookup;
   const FileEntry *FE = HeaderInfo.LookupFile(
       Filename, isAngled, FromDir, CurDir, CurFileEnt,
-      SearchPath, RelativePath);
+      SearchPath, RelativePath, SuggestedModule);
   if (FE) return FE;
 
   // Otherwise, see if this is a subframework header.  If so, this is relative
   // to one of the headers on the #include stack.  Walk the list of the current
   // headers on the #include stack and pass them to HeaderInfo.
+  // FIXME: SuggestedModule!
   if (IsFileLexer()) {
     if ((CurFileEnt = SourceMgr.getFileEntryForID(CurPPLexer->getFileID())))
       if ((FE = HeaderInfo.LookupSubframeworkHeader(Filename, CurFileEnt,
@@ -581,6 +591,7 @@ TryAgain:
     if (CodeComplete)
       CodeComplete->CodeCompleteDirective(
                                     CurPPLexer->getConditionalStackDepth() > 0);
+    setCodeCompletionReached();
     return;
   case tok::numeric_constant:  // # 7  GNU line marker directive.
     if (getLangOptions().AsmPreprocessor)
@@ -652,6 +663,9 @@ TryAgain:
     case tok::pp_unassert:
       //isExtension = true;  // FIXME: implement #unassert
       break;
+        
+    case tok::pp___export_macro__:
+      return HandleMacroExportDirective(Result);
     }
     break;
   }
@@ -758,9 +772,13 @@ void Preprocessor::HandleLineDirective(Token &Tok) {
 
   // Enforce C99 6.10.4p3: "The digit sequence shall not specify ... a
   // number greater than 2147483647".  C90 requires that the line # be <= 32767.
-  unsigned LineLimit = Features.C99 ? 2147483648U : 32768U;
+  unsigned LineLimit = 32768U;
+  if (Features.C99 || Features.CPlusPlus0x)
+    LineLimit = 2147483648U;
   if (LineNo >= LineLimit)
     Diag(DigitTok, diag::ext_pp_line_too_big) << LineLimit;
+  else if (Features.CPlusPlus0x && LineNo >= 32768U)
+    Diag(DigitTok, diag::warn_cxx98_compat_pp_line_too_big);
 
   int FilenameID = -1;
   Token StrTok;
@@ -777,7 +795,7 @@ void Preprocessor::HandleLineDirective(Token &Tok) {
   } else {
     // Parse and validate the string, converting it into a unique ID.
     StringLiteralParser Literal(&StrTok, 1, *this);
-    assert(!Literal.AnyWide && "Didn't allow wide strings in");
+    assert(Literal.isAscii() && "Didn't allow wide strings in");
     if (Literal.hadError)
       return DiscardUntilEndOfDirective();
     if (Literal.Pascal) {
@@ -825,7 +843,7 @@ static bool ReadLineMarkerFlags(bool &IsFileEntry, bool &IsFileExit,
     // If we are leaving the current presumed file, check to make sure the
     // presumed include stack isn't empty!
     FileID CurFileID =
-      SM.getDecomposedInstantiationLoc(FlagTok.getLocation()).first;
+      SM.getDecomposedExpansionLoc(FlagTok.getLocation()).first;
     PresumedLoc PLoc = SM.getPresumedLoc(FlagTok.getLocation());
     if (PLoc.isInvalid())
       return true;
@@ -834,7 +852,7 @@ static bool ReadLineMarkerFlags(bool &IsFileEntry, bool &IsFileExit,
     // different physical file, then we aren't in a "1" line marker flag region.
     SourceLocation IncLoc = PLoc.getIncludeLoc();
     if (IncLoc.isInvalid() ||
-        SM.getDecomposedInstantiationLoc(IncLoc).first != CurFileID) {
+        SM.getDecomposedExpansionLoc(IncLoc).first != CurFileID) {
       PP.Diag(FlagTok, diag::err_pp_linemarker_invalid_pop);
       PP.DiscardUntilEndOfDirective();
       return true;
@@ -910,7 +928,7 @@ void Preprocessor::HandleDigitDirective(Token &DigitTok) {
   } else {
     // Parse and validate the string, converting it into a unique ID.
     StringLiteralParser Literal(&StrTok, 1, *this);
-    assert(!Literal.AnyWide && "Didn't allow wide strings in");
+    assert(Literal.isAscii() && "Didn't allow wide strings in");
     if (Literal.hadError)
       return DiscardUntilEndOfDirective();
     if (Literal.Pascal) {
@@ -1000,6 +1018,37 @@ void Preprocessor::HandleIdentSCCSDirective(Token &Tok) {
   }
 }
 
+/// \brief Handle a #__export_macro__ directive.
+void Preprocessor::HandleMacroExportDirective(Token &Tok) {
+  Token MacroNameTok;
+  ReadMacroName(MacroNameTok, 2);
+  
+  // Error reading macro name?  If so, diagnostic already issued.
+  if (MacroNameTok.is(tok::eod))
+    return;
+
+  // Check to see if this is the last token on the #__export_macro__ line.
+  CheckEndOfDirective("__export_macro__");
+
+  // Okay, we finally have a valid identifier to undef.
+  MacroInfo *MI = getMacroInfo(MacroNameTok.getIdentifierInfo());
+  
+  // If the macro is not defined, this is an error.
+  if (MI == 0) {
+    Diag(MacroNameTok, diag::err_pp_export_non_macro)
+      << MacroNameTok.getIdentifierInfo();
+    return;
+  }
+  
+  // Note that this macro has now been exported.
+  MI->setExportLocation(MacroNameTok.getLocation());
+  
+  // If this macro definition came from a PCH file, mark it
+  // as having changed since serialization.
+  if (MI->isFromAST())
+    MI->setChangedAfterLoad();
+}
+
 //===----------------------------------------------------------------------===//
 // Preprocessor Include Directive Handling.
 //===----------------------------------------------------------------------===//
@@ -1011,7 +1060,7 @@ void Preprocessor::HandleIdentSCCSDirective(Token &Tok) {
 /// spelling of the filename, but is also expected to handle the case when
 /// this method decides to use a different buffer.
 bool Preprocessor::GetIncludeFilenameSpelling(SourceLocation Loc,
-                                              llvm::StringRef &Buffer) {
+                                              StringRef &Buffer) {
   // Get the text form of the filename.
   assert(!Buffer.empty() && "Can't have tokens with empty spellings!");
 
@@ -1020,27 +1069,27 @@ bool Preprocessor::GetIncludeFilenameSpelling(SourceLocation Loc,
   if (Buffer[0] == '<') {
     if (Buffer.back() != '>') {
       Diag(Loc, diag::err_pp_expects_filename);
-      Buffer = llvm::StringRef();
+      Buffer = StringRef();
       return true;
     }
     isAngled = true;
   } else if (Buffer[0] == '"') {
     if (Buffer.back() != '"') {
       Diag(Loc, diag::err_pp_expects_filename);
-      Buffer = llvm::StringRef();
+      Buffer = StringRef();
       return true;
     }
     isAngled = false;
   } else {
     Diag(Loc, diag::err_pp_expects_filename);
-    Buffer = llvm::StringRef();
+    Buffer = StringRef();
     return true;
   }
 
   // Diagnose #include "" as invalid.
   if (Buffer.size() <= 2) {
     Diag(Loc, diag::err_pp_empty_filename);
-    Buffer = llvm::StringRef();
+    Buffer = StringRef();
     return true;
   }
 
@@ -1070,6 +1119,7 @@ bool Preprocessor::ConcatenateIncludeName(
     
     // FIXME: Provide code completion for #includes.
     if (CurTok.is(tok::code_completion)) {
+      setCodeCompletionReached();
       Lex(CurTok);
       continue;
     }
@@ -1122,7 +1172,7 @@ void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
 
   // Reserve a buffer to get the spelling.
   llvm::SmallString<128> FilenameBuffer;
-  llvm::StringRef Filename;
+  StringRef Filename;
   SourceLocation End;
   
   switch (FilenameTok.getKind()) {
@@ -1171,23 +1221,44 @@ void Preprocessor::HandleIncludeDirective(SourceLocation HashLoc,
     return;
   }
 
+  // Complain about attempts to #include files in an audit pragma.
+  if (PragmaARCCFCodeAuditedLoc.isValid()) {
+    Diag(HashLoc, diag::err_pp_include_in_arc_cf_code_audited);
+    Diag(PragmaARCCFCodeAuditedLoc, diag::note_pragma_entered_here);
+
+    // Immediately leave the pragma.
+    PragmaARCCFCodeAuditedLoc = SourceLocation();
+  }
+
   // Search include directories.
   const DirectoryLookup *CurDir;
   llvm::SmallString<1024> SearchPath;
   llvm::SmallString<1024> RelativePath;
   // We get the raw path only if we have 'Callbacks' to which we later pass
   // the path.
+  StringRef SuggestedModule;
   const FileEntry *File = LookupFile(
       Filename, isAngled, LookupFrom, CurDir,
-      Callbacks ? &SearchPath : NULL, Callbacks ? &RelativePath : NULL);
-
+      Callbacks ? &SearchPath : NULL, Callbacks ? &RelativePath : NULL,
+      AutoModuleImport? &SuggestedModule : 0);
+
+  // If we are supposed to import a module rather than including the header,
+  // do so now.
+  if (!SuggestedModule.empty()) {
+    TheModuleLoader.loadModule(IncludeTok.getLocation(),
+                               Identifiers.get(SuggestedModule),
+                               FilenameTok.getLocation());
+    return;
+  }
+  
   // Notify the callback object that we've seen an inclusion directive.
   if (Callbacks)
     Callbacks->InclusionDirective(HashLoc, IncludeTok, Filename, isAngled, File,
                                   End, SearchPath, RelativePath);
 
   if (File == 0) {
-    Diag(FilenameTok, diag::warn_pp_file_not_found) << Filename;
+    if (!SuppressIncludeNotFoundError)
+      Diag(FilenameTok, diag::err_pp_file_not_found) << Filename;
     return;
   }
 
@@ -1284,7 +1355,7 @@ void Preprocessor::HandleIncludeMacrosDirective(SourceLocation HashLoc,
 /// closing ), updating MI with what we learn.  Return true if an error occurs
 /// parsing the arg list.
 bool Preprocessor::ReadMacroDefinitionArgList(MacroInfo *MI) {
-  llvm::SmallVector<IdentifierInfo*, 32> Arguments;
+  SmallVector<IdentifierInfo*, 32> Arguments;
 
   Token Tok;
   while (1) {
@@ -1298,8 +1369,10 @@ bool Preprocessor::ReadMacroDefinitionArgList(MacroInfo *MI) {
       Diag(Tok, diag::err_pp_expected_ident_in_arg_list);
       return true;
     case tok::ellipsis:  // #define X(... -> C99 varargs
-      // Warn if use of C99 feature in non-C99 mode.
-      if (!Features.C99) Diag(Tok, diag::ext_variadic_macro);
+      if (!Features.C99)
+        Diag(Tok, Features.CPlusPlus0x ? 
+             diag::warn_cxx98_compat_variadic_macro :
+             diag::ext_variadic_macro);
 
       // Lex the token after the identifier.
       LexUnexpandedToken(Tok);
@@ -1423,7 +1496,7 @@ void Preprocessor::HandleDefineDirective(Token &DefineTok) {
 
     // Read the first token after the arg list for down below.
     LexUnexpandedToken(Tok);
-  } else if (Features.C99) {
+  } else if (Features.C99 || Features.CPlusPlus0x) {
     // C99 requires whitespace between the macro definition and the body.  Emit
     // a diagnostic for something like "#define X+".
     Diag(Tok, diag::ext_c99_whitespace_required_after_macro_name);
@@ -1564,7 +1637,7 @@ void Preprocessor::HandleDefineDirective(Token &DefineTok) {
   // warn-because-unused-macro set. If it gets used it will be removed from set.
   if (isInPrimaryFile() && // don't warn for include'd macros.
       Diags->getDiagnosticLevel(diag::pp_macro_not_used,
-                               MI->getDefinitionLoc()) != Diagnostic::Ignored) {
+          MI->getDefinitionLoc()) != DiagnosticsEngine::Ignored) {
     MI->setIsWarnIfUnused(true);
     WarnUnusedMacroLocs.insert(MI->getDefinitionLoc());
   }
@@ -1765,7 +1838,7 @@ void Preprocessor::HandleElseDirective(Token &Result) {
 
   // Finally, skip the rest of the contents of this block.
   SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true,
-                               /*FoundElse*/true);
+                               /*FoundElse*/true, Result.getLocation());
 
   if (Callbacks)
     Callbacks->Else();
@@ -1798,7 +1871,8 @@ void Preprocessor::HandleElifDirective(Token &ElifToken) {
 
   // Finally, skip the rest of the contents of this block.
   SkipExcludedConditionalBlock(CI.IfLoc, /*Foundnonskip*/true,
-                               /*FoundElse*/CI.FoundElse);
+                               /*FoundElse*/CI.FoundElse,
+                               ElifToken.getLocation());
 
   if (Callbacks)
     Callbacks->Elif(SourceRange(ConditionalBegin, ConditionalEnd));
diff --git a/lib/Lex/PPExpressions.cpp b/lib/Lex/PPExpressions.cpp
index 8fcfc70a7c67..20f624a0bb12 100644
--- a/lib/Lex/PPExpressions.cpp
+++ b/lib/Lex/PPExpressions.cpp
@@ -23,6 +23,7 @@
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Lex/LexDiagnostic.h"
 #include "llvm/ADT/APSInt.h"
+#include "llvm/Support/ErrorHandling.h"
 using namespace clang;
 
 namespace {
@@ -83,20 +84,21 @@ static bool EvaluateDefined(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
   Result.setBegin(PeekTok.getLocation());
 
   // Get the next token, don't expand it.
-  PP.LexUnexpandedToken(PeekTok);
+  PP.LexUnexpandedNonComment(PeekTok);
 
   // Two options, it can either be a pp-identifier or a (.
   SourceLocation LParenLoc;
   if (PeekTok.is(tok::l_paren)) {
     // Found a paren, remember we saw it and skip it.
     LParenLoc = PeekTok.getLocation();
-    PP.LexUnexpandedToken(PeekTok);
+    PP.LexUnexpandedNonComment(PeekTok);
   }
 
   if (PeekTok.is(tok::code_completion)) {
     if (PP.getCodeCompletionHandler())
       PP.getCodeCompletionHandler()->CodeCompleteMacroName(false);
-    PP.LexUnexpandedToken(PeekTok);
+    PP.setCodeCompletionReached();
+    PP.LexUnexpandedNonComment(PeekTok);
   }
   
   // If we don't have a pp-identifier now, this is an error.
@@ -115,12 +117,16 @@ static bool EvaluateDefined(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
     PP.markMacroAsUsed(Macro);
   }
 
-  // Consume identifier.
-  Result.setEnd(PeekTok.getLocation());
-  PP.LexUnexpandedToken(PeekTok);
+  // Invoke the 'defined' callback.
+  if (PPCallbacks *Callbacks = PP.getPPCallbacks())
+    Callbacks->Defined(PeekTok);
 
   // If we are in parens, ensure we have a trailing ).
   if (LParenLoc.isValid()) {
+    // Consume identifier.
+    Result.setEnd(PeekTok.getLocation());
+    PP.LexUnexpandedNonComment(PeekTok);
+
     if (PeekTok.isNot(tok::r_paren)) {
       PP.Diag(PeekTok.getLocation(), diag::err_pp_missing_rparen) << "defined";
       PP.Diag(LParenLoc, diag::note_matching) << "(";
@@ -129,6 +135,10 @@ static bool EvaluateDefined(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
     // Consume the ).
     Result.setEnd(PeekTok.getLocation());
     PP.LexNonComment(PeekTok);
+  } else {
+    // Consume identifier.
+    Result.setEnd(PeekTok.getLocation());
+    PP.LexNonComment(PeekTok);
   }
 
   // Success, remember that we saw defined(X).
@@ -152,7 +162,8 @@ static bool EvaluateValue(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
   if (PeekTok.is(tok::code_completion)) {
     if (PP.getCodeCompletionHandler())
       PP.getCodeCompletionHandler()->CodeCompletePreprocessorExpression();
-    PP.LexUnexpandedToken(PeekTok);
+    PP.setCodeCompletionReached();
+    PP.LexNonComment(PeekTok);
   }
       
   // If this token's spelling is a pp-identifier, check to see if it is
@@ -188,7 +199,7 @@ static bool EvaluateValue(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
   case tok::numeric_constant: {
     llvm::SmallString<64> IntegerBuffer;
     bool NumberInvalid = false;
-    llvm::StringRef Spelling = PP.getSpelling(PeekTok, IntegerBuffer, 
+    StringRef Spelling = PP.getSpelling(PeekTok, IntegerBuffer, 
                                               &NumberInvalid);
     if (NumberInvalid)
       return true; // a diagnostic was already reported
@@ -205,9 +216,9 @@ static bool EvaluateValue(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
     assert(Literal.isIntegerLiteral() && "Unknown ppnumber");
 
     // long long is a C99 feature.
-    if (!PP.getLangOptions().C99 && !PP.getLangOptions().CPlusPlus0x
-        && Literal.isLongLong)
-      PP.Diag(PeekTok, diag::ext_longlong);
+    if (!PP.getLangOptions().C99 && Literal.isLongLong)
+      PP.Diag(PeekTok, PP.getLangOptions().CPlusPlus0x ?
+              diag::warn_cxx98_compat_longlong : diag::ext_longlong);
 
     // Parse the integer literal into Result.
     if (Literal.GetIntegerValue(Result.Val)) {
@@ -236,15 +247,18 @@ static bool EvaluateValue(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
     PP.LexNonComment(PeekTok);
     return false;
   }
-  case tok::char_constant: {   // 'x'
+  case tok::char_constant:          // 'x'
+  case tok::wide_char_constant: {   // L'x'
+  case tok::utf16_char_constant:    // u'x'
+  case tok::utf32_char_constant:    // U'x'
     llvm::SmallString<32> CharBuffer;
     bool CharInvalid = false;
-    llvm::StringRef ThisTok = PP.getSpelling(PeekTok, CharBuffer, &CharInvalid);
+    StringRef ThisTok = PP.getSpelling(PeekTok, CharBuffer, &CharInvalid);
     if (CharInvalid)
       return true;
 
     CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(),
-                              PeekTok.getLocation(), PP);
+                              PeekTok.getLocation(), PP, PeekTok.getKind());
     if (Literal.hadError())
       return true;  // A diagnostic was already emitted.
 
@@ -255,6 +269,10 @@ static bool EvaluateValue(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
       NumBits = TI.getIntWidth();
     else if (Literal.isWide())
       NumBits = TI.getWCharWidth();
+    else if (Literal.isUTF16())
+      NumBits = TI.getChar16Width();
+    else if (Literal.isUTF32())
+      NumBits = TI.getChar32Width();
     else
       NumBits = TI.getCharWidth();
 
@@ -262,8 +280,9 @@ static bool EvaluateValue(PPValue &Result, Token &PeekTok, DefinedTracker &DT,
     llvm::APSInt Val(NumBits);
     // Set the value.
     Val = Literal.getValue();
-    // Set the signedness.
-    Val.setIsUnsigned(!PP.getLangOptions().CharIsSigned);
+    // Set the signedness. UTF-16 and UTF-32 are always unsigned
+    if (!Literal.isUTF16() && !Literal.isUTF32())
+      Val.setIsUnsigned(!PP.getLangOptions().CharIsSigned);
 
     if (Result.Val.getBitWidth() > Val.getBitWidth()) {
       Result.Val = Val.extend(Result.Val.getBitWidth());
@@ -521,7 +540,7 @@ static bool EvaluateDirectiveSubExpr(PPValue &LHS, unsigned MinPrec,
 
     bool Overflow = false;
     switch (Operator) {
-    default: assert(0 && "Unknown operator token!");
+    default: llvm_unreachable("Unknown operator token!");
     case tok::percent:
       if (RHS.Val != 0)
         Res = LHS.Val % RHS.Val;
@@ -704,7 +723,7 @@ EvaluateDirectiveExpression(IdentifierInfo *&IfNDefMacro) {
   
   // Peek ahead one token.
   Token Tok;
-  Lex(Tok);
+  LexNonComment(Tok);
   
   // C99 6.10.1p3 - All expressions are evaluated as intmax_t or uintmax_t.
   unsigned BitWidth = getTargetInfo().getIntMaxTWidth();
@@ -759,4 +778,3 @@ EvaluateDirectiveExpression(IdentifierInfo *&IfNDefMacro) {
   DisableMacroExpansion = DisableMacroExpansionAtStartOfDirective;
   return ResVal.Val != 0;
 }
-
diff --git a/lib/Lex/PPLexerChange.cpp b/lib/Lex/PPLexerChange.cpp
index bf28199b888a..25a98ae47b6e 100644
--- a/lib/Lex/PPLexerChange.cpp
+++ b/lib/Lex/PPLexerChange.cpp
@@ -89,7 +89,14 @@ void Preprocessor::EnterSourceFile(FileID FID, const DirectoryLookup *CurDir,
       << std::string(SourceMgr.getBufferName(FileStart)) << "";
     return;
   }
-  
+
+  if (isCodeCompletionEnabled() &&
+      SourceMgr.getFileEntryForID(FID) == CodeCompletionFile) {
+    CodeCompletionFileLoc = SourceMgr.getLocForStartOfFile(FID);
+    CodeCompletionLoc =
+        CodeCompletionFileLoc.getLocWithOffset(CodeCompletionOffset);
+  }
+
   EnterSourceFileWithLexer(new Lexer(FID, InputFile, *this), CurDir);
   return;
 }
@@ -106,7 +113,9 @@ void Preprocessor::EnterSourceFileWithLexer(Lexer *TheLexer,
   CurLexer.reset(TheLexer);
   CurPPLexer = TheLexer;
   CurDirLookup = CurDir;
-
+  if (CurLexerKind != CLK_LexAfterModuleImport)
+    CurLexerKind = CLK_Lexer;
+  
   // Notify the client, if desired, that we are in a new source file.
   if (Callbacks && !CurLexer->Is_PragmaLexer) {
     SrcMgr::CharacteristicKind FileType =
@@ -128,7 +137,9 @@ void Preprocessor::EnterSourceFileWithPTH(PTHLexer *PL,
   CurDirLookup = CurDir;
   CurPTHLexer.reset(PL);
   CurPPLexer = CurPTHLexer.get();
-
+  if (CurLexerKind != CLK_LexAfterModuleImport)
+    CurLexerKind = CLK_PTHLexer;
+  
   // Notify the client, if desired, that we are in a new source file.
   if (Callbacks) {
     FileID FID = CurPPLexer->getFileID();
@@ -152,6 +163,8 @@ void Preprocessor::EnterMacro(Token &Tok, SourceLocation ILEnd,
     CurTokenLexer.reset(TokenLexerCache[--NumCachedTokenLexers]);
     CurTokenLexer->Init(Tok, ILEnd, Args);
   }
+  if (CurLexerKind != CLK_LexAfterModuleImport)
+    CurLexerKind = CLK_TokenLexer;
 }
 
 /// EnterTokenStream - Add a "macro" context to the top of the include stack,
@@ -181,6 +194,8 @@ void Preprocessor::EnterTokenStream(const Token *Toks, unsigned NumToks,
     CurTokenLexer.reset(TokenLexerCache[--NumCachedTokenLexers]);
     CurTokenLexer->Init(Toks, NumToks, DisableMacroExpansion, OwnsTokens);
   }
+  if (CurLexerKind != CLK_LexAfterModuleImport)
+    CurLexerKind = CLK_TokenLexer;
 }
 
 /// HandleEndOfFile - This callback is invoked when the lexer hits the end of
@@ -201,9 +216,50 @@ bool Preprocessor::HandleEndOfFile(Token &Result, bool isEndOfMacro) {
     }
   }
 
+  // Complain about reaching an EOF within arc_cf_code_audited.
+  if (PragmaARCCFCodeAuditedLoc.isValid()) {
+    Diag(PragmaARCCFCodeAuditedLoc, diag::err_pp_eof_in_arc_cf_code_audited);
+
+    // Recover by leaving immediately.
+    PragmaARCCFCodeAuditedLoc = SourceLocation();
+  }
+
   // If this is a #include'd file, pop it off the include stack and continue
   // lexing the #includer file.
   if (!IncludeMacroStack.empty()) {
+
+    // If we lexed the code-completion file, act as if we reached EOF.
+    if (isCodeCompletionEnabled() && CurPPLexer &&
+        SourceMgr.getLocForStartOfFile(CurPPLexer->getFileID()) ==
+            CodeCompletionFileLoc) {
+      if (CurLexer) {
+        Result.startToken();
+        CurLexer->FormTokenWithChars(Result, CurLexer->BufferEnd, tok::eof);
+        CurLexer.reset();
+      } else {
+        assert(CurPTHLexer && "Got EOF but no current lexer set!");
+        CurPTHLexer->getEOF(Result);
+        CurPTHLexer.reset();
+      }
+
+      CurPPLexer = 0;
+      return true;
+    }
+
+    if (!isEndOfMacro && CurPPLexer &&
+        SourceMgr.getIncludeLoc(CurPPLexer->getFileID()).isValid()) {
+      // Notify SourceManager to record the number of FileIDs that were created
+      // during lexing of the #include'd file.
+      unsigned NumFIDs =
+          SourceMgr.local_sloc_entry_size() -
+          CurPPLexer->getInitialNumSLocEntries() + 1/*#include'd file*/;
+      SourceMgr.setNumCreatedFIDsForFileID(CurPPLexer->getFileID(), NumFIDs);
+    }
+
+    FileID ExitedFID;
+    if (Callbacks && !isEndOfMacro && CurPPLexer)
+      ExitedFID = CurPPLexer->getFileID();
+    
     // We're done with the #included file.
     RemoveTopOfLexerStack();
 
@@ -212,7 +268,7 @@ bool Preprocessor::HandleEndOfFile(Token &Result, bool isEndOfMacro) {
       SrcMgr::CharacteristicKind FileType =
         SourceMgr.getFileCharacteristic(CurPPLexer->getSourceLocation());
       Callbacks->FileChanged(CurPPLexer->getSourceLocation(),
-                             PPCallbacks::ExitFile, FileType);
+                             PPCallbacks::ExitFile, FileType, ExitedFID);
     }
 
     // Client should lex another token.
diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index ecd4d4cfc68b..e10c95c75f25 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -21,10 +21,12 @@
 #include "clang/Lex/LexDiagnostic.h"
 #include "clang/Lex/CodeCompletionHandler.h"
 #include "clang/Lex/ExternalPreprocessorSource.h"
+#include "clang/Lex/LiteralSupport.h"
 #include "llvm/ADT/StringSwitch.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/Config/config.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/ErrorHandling.h"
 #include <cstdio>
 #include <ctime>
 using namespace clang;
@@ -91,9 +93,10 @@ void Preprocessor::RegisterBuiltinMacros() {
   Ident__has_attribute    = RegisterBuiltinMacro(*this, "__has_attribute");
   Ident__has_include      = RegisterBuiltinMacro(*this, "__has_include");
   Ident__has_include_next = RegisterBuiltinMacro(*this, "__has_include_next");
+  Ident__has_warning      = RegisterBuiltinMacro(*this, "__has_warning");
 
   // Microsoft Extensions.
-  if (Features.Microsoft) 
+  if (Features.MicrosoftExt) 
     Ident__pragma = RegisterBuiltinMacro(*this, "__pragma");
   else
     Ident__pragma = 0;
@@ -185,7 +188,8 @@ bool Preprocessor::HandleMacroExpandedIdentifier(Token &Identifier,
 
   // If this is a builtin macro, like __LINE__ or _Pragma, handle it specially.
   if (MI->isBuiltinMacro()) {
-    if (Callbacks) Callbacks->MacroExpands(Identifier, MI);
+    if (Callbacks) Callbacks->MacroExpands(Identifier, MI,
+                                           Identifier.getLocation());
     ExpandBuiltinMacro(Identifier);
     return false;
   }
@@ -226,13 +230,14 @@ bool Preprocessor::HandleMacroExpandedIdentifier(Token &Identifier,
   // Notice that this macro has been used.
   markMacroAsUsed(MI);
 
-  if (Callbacks) Callbacks->MacroExpands(Identifier, MI);
-  
-  // If we started lexing a macro, enter the macro expansion body.
-
   // Remember where the token is expanded.
   SourceLocation ExpandLoc = Identifier.getLocation();
 
+  if (Callbacks) Callbacks->MacroExpands(Identifier, MI,
+                                         SourceRange(ExpandLoc, ExpansionEnd));
+  
+  // If we started lexing a macro, enter the macro expansion body.
+
   // If this macro expands to no tokens, don't bother to push it onto the
   // expansion stack, only to take it right back off.
   if (MI->getNumTokens() == 0) {
@@ -255,7 +260,6 @@ bool Preprocessor::HandleMacroExpandedIdentifier(Token &Identifier,
       if (HadLeadingSpace) Identifier.setFlag(Token::LeadingSpace);
     }
     Identifier.setFlag(Token::LeadingEmptyMacro);
-    LastEmptyMacroExpansionLoc = ExpandLoc;
     ++NumFastMacroExpanded;
     return false;
 
@@ -284,8 +288,8 @@ bool Preprocessor::HandleMacroExpandedIdentifier(Token &Identifier,
     // Update the tokens location to include both its expansion and physical
     // locations.
     SourceLocation Loc =
-      SourceMgr.createInstantiationLoc(Identifier.getLocation(), ExpandLoc,
-                                       ExpansionEnd,Identifier.getLength());
+      SourceMgr.createExpansionLoc(Identifier.getLocation(), ExpandLoc,
+                                   ExpansionEnd,Identifier.getLength());
     Identifier.setLocation(Loc);
 
     // If this is a disabled macro or #define X X, we must mark the result as
@@ -333,7 +337,7 @@ MacroArgs *Preprocessor::ReadFunctionLikeMacroArgs(Token &MacroName,
   // ArgTokens - Build up a list of tokens that make up each argument.  Each
   // argument is separated by an EOF token.  Use a SmallVector so we can avoid
   // heap allocations in the common case.
-  llvm::SmallVector<Token, 64> ArgTokens;
+  SmallVector<Token, 64> ArgTokens;
 
   unsigned NumActuals = 0;
   while (Tok.isNot(tok::r_paren)) {
@@ -352,13 +356,6 @@ MacroArgs *Preprocessor::ReadFunctionLikeMacroArgs(Token &MacroName,
       // an argument value in a macro could expand to ',' or '(' or ')'.
       LexUnexpandedToken(Tok);
 
-      if (Tok.is(tok::code_completion)) {
-        if (CodeComplete)
-          CodeComplete->CodeCompleteMacroArgument(MacroName.getIdentifierInfo(),
-                                                  MI, NumActuals);
-        LexUnexpandedToken(Tok);
-      }
-      
       if (Tok.is(tok::eof) || Tok.is(tok::eod)) { // "#if f(<eof>" & "#if f(\n"
         Diag(MacroName, diag::err_unterm_macro_invoc);
         // Do not lose the EOF/EOD.  Return it to the client.
@@ -393,7 +390,15 @@ MacroArgs *Preprocessor::ReadFunctionLikeMacroArgs(Token &MacroName,
         if (MacroInfo *MI = getMacroInfo(Tok.getIdentifierInfo()))
           if (!MI->isEnabled())
             Tok.setFlag(Token::DisableExpand);
+      } else if (Tok.is(tok::code_completion)) {
+        if (CodeComplete)
+          CodeComplete->CodeCompleteMacroArgument(MacroName.getIdentifierInfo(),
+                                                  MI, NumActuals);
+        // Don't mark that we reached the code-completion point because the
+        // parser is going to handle the token and there will be another
+        // code-completion callback.
       }
+
       ArgTokens.push_back(Tok);
     }
 
@@ -416,8 +421,10 @@ MacroArgs *Preprocessor::ReadFunctionLikeMacroArgs(Token &MacroName,
 
     // Empty arguments are standard in C99 and C++0x, and are supported as an extension in
     // other modes.
-    if (ArgTokens.size() == ArgTokenStart && !Features.C99 && !Features.CPlusPlus0x)
-      Diag(Tok, diag::ext_empty_fnmacro_arg);
+    if (ArgTokens.size() == ArgTokenStart && !Features.C99)
+      Diag(Tok, Features.CPlusPlus0x ?
+           diag::warn_cxx98_compat_empty_fnmacro_arg :
+           diag::ext_empty_fnmacro_arg);
 
     // Add a marker EOF token to the end of the token list for this argument.
     Token EOFTok;
@@ -487,8 +494,7 @@ MacroArgs *Preprocessor::ReadFunctionLikeMacroArgs(Token &MacroName,
     return 0;
   }
 
-  return MacroArgs::create(MI, ArgTokens.data(), ArgTokens.size(),
-                           isVarargsElided, *this);
+  return MacroArgs::create(MI, ArgTokens, isVarargsElided, *this);
 }
 
 /// \brief Keeps macro expanded tokens for TokenLexers.
@@ -497,7 +503,7 @@ MacroArgs *Preprocessor::ReadFunctionLikeMacroArgs(Token &MacroName,
 /// going to lex in the cache and when it finishes the tokens are removed
 /// from the end of the cache.
 Token *Preprocessor::cacheMacroExpandedTokens(TokenLexer *tokLexer,
-                                              llvm::ArrayRef<Token> tokens) {
+                                              ArrayRef<Token> tokens) {
   assert(tokLexer);
   if (tokens.empty())
     return 0;
@@ -597,34 +603,48 @@ static bool HasFeature(const Preprocessor &PP, const IdentifierInfo *II) {
            .Case("objc_arc", LangOpts.ObjCAutoRefCount)
            .Case("objc_arc_weak", LangOpts.ObjCAutoRefCount && 
                  LangOpts.ObjCRuntimeHasWeak)
+           .Case("objc_fixed_enum", LangOpts.ObjC2)
+           .Case("objc_instancetype", LangOpts.ObjC2)
            .Case("objc_nonfragile_abi", LangOpts.ObjCNonFragileABI)
            .Case("objc_weak_class", LangOpts.ObjCNonFragileABI)
            .Case("ownership_holds", true)
            .Case("ownership_returns", true)
            .Case("ownership_takes", true)
            // C1X features
+           .Case("c_alignas", LangOpts.C1X)
            .Case("c_generic_selections", LangOpts.C1X)
            .Case("c_static_assert", LangOpts.C1X)
            // C++0x features
            .Case("cxx_access_control_sfinae", LangOpts.CPlusPlus0x)
            .Case("cxx_alias_templates", LangOpts.CPlusPlus0x)
+           .Case("cxx_alignas", LangOpts.CPlusPlus0x)
            .Case("cxx_attributes", LangOpts.CPlusPlus0x)
            .Case("cxx_auto_type", LangOpts.CPlusPlus0x)
+         //.Case("cxx_constexpr", false);
            .Case("cxx_decltype", LangOpts.CPlusPlus0x)
            .Case("cxx_default_function_template_args", LangOpts.CPlusPlus0x)
            .Case("cxx_delegating_constructors", LangOpts.CPlusPlus0x)
            .Case("cxx_deleted_functions", LangOpts.CPlusPlus0x)
+           .Case("cxx_explicit_conversions", LangOpts.CPlusPlus0x)
+         //.Case("cxx_generalized_initializers", LangOpts.CPlusPlus0x)
+           .Case("cxx_implicit_moves", LangOpts.CPlusPlus0x)
+         //.Case("cxx_inheriting_constructors", false)
            .Case("cxx_inline_namespaces", LangOpts.CPlusPlus0x)
          //.Case("cxx_lambdas", false)
+           .Case("cxx_nonstatic_member_init", LangOpts.CPlusPlus0x)
            .Case("cxx_noexcept", LangOpts.CPlusPlus0x)
            .Case("cxx_nullptr", LangOpts.CPlusPlus0x)
            .Case("cxx_override_control", LangOpts.CPlusPlus0x)
            .Case("cxx_range_for", LangOpts.CPlusPlus0x)
+         //.Case("cxx_raw_string_literals", false)
            .Case("cxx_reference_qualified_functions", LangOpts.CPlusPlus0x)
            .Case("cxx_rvalue_references", LangOpts.CPlusPlus0x)
            .Case("cxx_strong_enums", LangOpts.CPlusPlus0x)
            .Case("cxx_static_assert", LangOpts.CPlusPlus0x)
            .Case("cxx_trailing_return", LangOpts.CPlusPlus0x)
+         //.Case("cxx_unicode_literals", false)
+         //.Case("cxx_unrestricted_unions", false)
+         //.Case("cxx_user_literals", false)
            .Case("cxx_variadic_templates", LangOpts.CPlusPlus0x)
            // Type traits
            .Case("has_nothrow_assign", LangOpts.CPlusPlus)
@@ -639,16 +659,31 @@ static bool HasFeature(const Preprocessor &PP, const IdentifierInfo *II) {
            .Case("is_base_of", LangOpts.CPlusPlus)
            .Case("is_class", LangOpts.CPlusPlus)
            .Case("is_convertible_to", LangOpts.CPlusPlus)
-           .Case("is_empty", LangOpts.CPlusPlus)
+            // __is_empty is available only if the horrible
+            // "struct __is_empty" parsing hack hasn't been needed in this
+            // translation unit. If it has, __is_empty reverts to a normal
+            // identifier and __has_feature(is_empty) evaluates false.
+           .Case("is_empty", 
+                 LangOpts.CPlusPlus && 
+                 PP.getIdentifierInfo("__is_empty")->getTokenID()
+                                                            != tok::identifier)
            .Case("is_enum", LangOpts.CPlusPlus)
            .Case("is_literal", LangOpts.CPlusPlus)
            .Case("is_standard_layout", LangOpts.CPlusPlus)
-           .Case("is_pod", LangOpts.CPlusPlus)
+           // __is_pod is available only if the horrible
+           // "struct __is_pod" parsing hack hasn't been needed in this
+           // translation unit. If it has, __is_pod reverts to a normal
+           // identifier and __has_feature(is_pod) evaluates false.
+           .Case("is_pod", 
+                 LangOpts.CPlusPlus && 
+                 PP.getIdentifierInfo("__is_pod")->getTokenID()
+                                                            != tok::identifier)
            .Case("is_polymorphic", LangOpts.CPlusPlus)
            .Case("is_trivial", LangOpts.CPlusPlus)
            .Case("is_trivially_copyable", LangOpts.CPlusPlus)
            .Case("is_union", LangOpts.CPlusPlus)
            .Case("tls", PP.getTargetInfo().isTLSSupported())
+           .Case("underlying_type", LangOpts.CPlusPlus)
            .Default(false);
 }
 
@@ -661,7 +696,8 @@ static bool HasExtension(const Preprocessor &PP, const IdentifierInfo *II) {
 
   // If the use of an extension results in an error diagnostic, extensions are
   // effectively unavailable, so just return false here.
-  if (PP.getDiagnostics().getExtensionHandlingBehavior()==Diagnostic::Ext_Error)
+  if (PP.getDiagnostics().getExtensionHandlingBehavior() ==
+      DiagnosticsEngine::Ext_Error)
     return false;
 
   const LangOptions &LangOpts = PP.getLangOptions();
@@ -670,12 +706,16 @@ static bool HasExtension(const Preprocessor &PP, const IdentifierInfo *II) {
   // must be less restrictive than HasFeature's.
   return llvm::StringSwitch<bool>(II->getName())
            // C1X features supported by other languages as extensions.
+           .Case("c_alignas", true)
            .Case("c_generic_selections", true)
            .Case("c_static_assert", true)
            // C++0x features supported by other languages as extensions.
            .Case("cxx_deleted_functions", LangOpts.CPlusPlus)
+           .Case("cxx_explicit_conversions", LangOpts.CPlusPlus)
            .Case("cxx_inline_namespaces", LangOpts.CPlusPlus)
+           .Case("cxx_nonstatic_member_init", LangOpts.CPlusPlus)
            .Case("cxx_override_control", LangOpts.CPlusPlus)
+           .Case("cxx_range_for", LangOpts.CPlusPlus)
            .Case("cxx_reference_qualified_functions", LangOpts.CPlusPlus)
            .Case("cxx_rvalue_references", LangOpts.CPlusPlus)
            .Default(false);
@@ -714,7 +754,7 @@ static bool EvaluateHasIncludeCommon(Token &Tok,
 
   // Reserve a buffer to get the spelling.
   llvm::SmallString<128> FilenameBuffer;
-  llvm::StringRef Filename;
+  StringRef Filename;
   SourceLocation EndLoc;
   
   switch (Tok.getKind()) {
@@ -753,7 +793,7 @@ static bool EvaluateHasIncludeCommon(Token &Tok,
   // Search include directories.
   const DirectoryLookup *CurDir;
   const FileEntry *File =
-      PP.LookupFile(Filename, isAngled, LookupFrom, CurDir, NULL, NULL);
+      PP.LookupFile(Filename, isAngled, LookupFrom, CurDir, NULL, NULL, NULL);
 
   // Get the result value.  Result = true means the file exists.
   bool Result = File != 0;
@@ -837,7 +877,7 @@ void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
     // can matter for a function-like macro that expands to contain __LINE__.
     // Skip down through expansion points until we find a file loc for the
     // end of the expansion history.
-    Loc = SourceMgr.getInstantiationRange(Loc).second;
+    Loc = SourceMgr.getExpansionRange(Loc).second;
     PresumedLoc PLoc = SourceMgr.getPresumedLoc(Loc);
 
     // __LINE__ expands to a simple numeric value.
@@ -874,18 +914,18 @@ void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
       ComputeDATE_TIME(DATELoc, TIMELoc, *this);
     Tok.setKind(tok::string_literal);
     Tok.setLength(strlen("\"Mmm dd yyyy\""));
-    Tok.setLocation(SourceMgr.createInstantiationLoc(DATELoc, Tok.getLocation(),
-                                                     Tok.getLocation(),
-                                                     Tok.getLength()));
+    Tok.setLocation(SourceMgr.createExpansionLoc(DATELoc, Tok.getLocation(),
+                                                 Tok.getLocation(),
+                                                 Tok.getLength()));
     return;
   } else if (II == Ident__TIME__) {
     if (!TIMELoc.isValid())
       ComputeDATE_TIME(DATELoc, TIMELoc, *this);
     Tok.setKind(tok::string_literal);
     Tok.setLength(strlen("\"hh:mm:ss\""));
-    Tok.setLocation(SourceMgr.createInstantiationLoc(TIMELoc, Tok.getLocation(),
-                                                     Tok.getLocation(),
-                                                     Tok.getLength()));
+    Tok.setLocation(SourceMgr.createExpansionLoc(TIMELoc, Tok.getLocation(),
+                                                 Tok.getLocation(),
+                                                 Tok.getLength()));
     return;
   } else if (II == Ident__INCLUDE_LEVEL__) {
     // Compute the presumed include depth of this token.  This can be affected
@@ -923,7 +963,7 @@ void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
       Result = "??? ??? ?? ??:??:?? ????\n";
     }
     // Surround the string with " and strip the trailing newline.
-    OS << '"' << llvm::StringRef(Result, strlen(Result)-1) << '"';
+    OS << '"' << StringRef(Result, strlen(Result)-1) << '"';
     Tok.setKind(tok::string_literal);
   } else if (II == Ident__COUNTER__) {
     // __COUNTER__ expands to a simple numeric value.
@@ -983,10 +1023,78 @@ void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
       Value = EvaluateHasIncludeNext(Tok, II, *this);
     OS << (int)Value;
     Tok.setKind(tok::numeric_constant);
+  } else if (II == Ident__has_warning) {
+    // The argument should be a parenthesized string literal.
+    // The argument to these builtins should be a parenthesized identifier.
+    SourceLocation StartLoc = Tok.getLocation();    
+    bool IsValid = false;
+    bool Value = false;
+    // Read the '('.
+    Lex(Tok);
+    do {
+      if (Tok.is(tok::l_paren)) {      
+        // Read the string.
+        Lex(Tok);
+      
+        // We need at least one string literal.
+        if (!Tok.is(tok::string_literal)) {
+          StartLoc = Tok.getLocation();
+          IsValid = false;
+          // Eat tokens until ')'.
+          do Lex(Tok); while (!(Tok.is(tok::r_paren) || Tok.is(tok::eod)));
+          break;
+        }
+        
+        // String concatenation allows multiple strings, which can even come
+        // from macro expansion.
+        SmallVector<Token, 4> StrToks;
+        while (Tok.is(tok::string_literal)) {
+          StrToks.push_back(Tok);
+          LexUnexpandedToken(Tok);
+        }
+        
+        // Is the end a ')'?
+        if (!(IsValid = Tok.is(tok::r_paren)))
+          break;
+        
+        // Concatenate and parse the strings.
+        StringLiteralParser Literal(&StrToks[0], StrToks.size(), *this);
+        assert(Literal.isAscii() && "Didn't allow wide strings in");
+        if (Literal.hadError)
+          break;
+        if (Literal.Pascal) {
+          Diag(Tok, diag::warn_pragma_diagnostic_invalid);
+          break;
+        }
+        
+        StringRef WarningName(Literal.GetString());
+        
+        if (WarningName.size() < 3 || WarningName[0] != '-' ||
+            WarningName[1] != 'W') {
+          Diag(StrToks[0].getLocation(), diag::warn_has_warning_invalid_option);
+          break;
+        }
+        
+        // Finally, check if the warning flags maps to a diagnostic group.
+        // We construct a SmallVector here to talk to getDiagnosticIDs().
+        // Although we don't use the result, this isn't a hot path, and not
+        // worth special casing.
+        llvm::SmallVector<diag::kind, 10> Diags;
+        Value = !getDiagnostics().getDiagnosticIDs()->
+          getDiagnosticsInGroup(WarningName.substr(2), Diags);
+      }
+    } while (false);
+    
+    if (!IsValid)
+      Diag(StartLoc, diag::err_warning_check_malformed);
+
+    OS << (int)Value;
+    Tok.setKind(tok::numeric_constant);
   } else {
-    assert(0 && "Unknown identifier!");
+    llvm_unreachable("Unknown identifier!");
   }
-  CreateString(OS.str().data(), OS.str().size(), Tok, Tok.getLocation());
+  CreateString(OS.str().data(), OS.str().size(), Tok,
+               Tok.getLocation(), Tok.getLocation());
 }
 
 void Preprocessor::markMacroAsUsed(MacroInfo *MI) {
diff --git a/lib/Lex/PTHLexer.cpp b/lib/Lex/PTHLexer.cpp
index e5ef0fdf20eb..e0c4cf0c16c8 100644
--- a/lib/Lex/PTHLexer.cpp
+++ b/lib/Lex/PTHLexer.cpp
@@ -73,7 +73,7 @@ LexNextToken:
   Tok.setKind(TKind);
   Tok.setFlag(TFlags);
   assert(!LexingRawMode);
-  Tok.setLocation(FileStartLoc.getFileLocWithOffset(FileOffset));
+  Tok.setLocation(FileStartLoc.getLocWithOffset(FileOffset));
   Tok.setLength(Len);
 
   // Handle identifiers.
@@ -147,7 +147,7 @@ bool PTHLexer::LexEndOfFile(Token &Result) {
 
   // If we are in a #if directive, emit an error.
   while (!ConditionalStack.empty()) {
-    if (!PP->isCodeCompletionFile(FileStartLoc))
+    if (PP->getCodeCompletionFileLoc() != FileStartLoc)
       PP->Diag(ConditionalStack.back().IfLoc,
                diag::err_pp_unterminated_conditional);
     ConditionalStack.pop_back();
@@ -297,7 +297,7 @@ SourceLocation PTHLexer::getSourceLocation() {
   // NOTE: This is a virtual function; hence it is defined out-of-line.
   const unsigned char *OffsetPtr = CurPtr + (DISK_TOKEN_SIZE - 4);
   uint32_t Offset = ReadLE32(OffsetPtr);
-  return FileStartLoc.getFileLocWithOffset(Offset);
+  return FileStartLoc.getLocWithOffset(Offset);
 }
 
 //===----------------------------------------------------------------------===//
@@ -380,7 +380,7 @@ public:
   }
 
   static unsigned ComputeHash(const internal_key_type& a) {
-    return llvm::HashString(llvm::StringRef(a.first, a.second));
+    return llvm::HashString(StringRef(a.first, a.second));
   }
 
   // This hopefully will just get inlined and removed by the optimizer.
@@ -431,11 +431,12 @@ PTHManager::~PTHManager() {
   free(PerIDCache);
 }
 
-static void InvalidPTH(Diagnostic &Diags, const char *Msg) {
-  Diags.Report(Diags.getCustomDiagID(Diagnostic::Error, Msg));
+static void InvalidPTH(DiagnosticsEngine &Diags, const char *Msg) {
+  Diags.Report(Diags.getCustomDiagID(DiagnosticsEngine::Error, Msg));
 }
 
-PTHManager *PTHManager::Create(const std::string &file, Diagnostic &Diags) {
+PTHManager *PTHManager::Create(const std::string &file,
+                               DiagnosticsEngine &Diags) {
   // Memory map the PTH file.
   llvm::OwningPtr<llvm::MemoryBuffer> File;
 
@@ -572,10 +573,10 @@ IdentifierInfo* PTHManager::LazilyCreateIdentifierInfo(unsigned PersistentID) {
   return II;
 }
 
-IdentifierInfo* PTHManager::get(llvm::StringRef Name) {
+IdentifierInfo* PTHManager::get(StringRef Name) {
   PTHStringIdLookup& SL = *((PTHStringIdLookup*)StringIdLookup);
   // Double check our assumption that the last character isn't '\0'.
-  assert(Name.empty() || Name.data()[Name.size()-1] != '\0');
+  assert(Name.empty() || Name.back() != '\0');
   PTHStringIdLookup::iterator I = SL.find(std::make_pair(Name.data(),
                                                          Name.size()));
   if (I == SL.end()) // No identifier found?
diff --git a/lib/Lex/Pragma.cpp b/lib/Lex/Pragma.cpp
index e6b28c13317b..f6532c2175a1 100644
--- a/lib/Lex/Pragma.cpp
+++ b/lib/Lex/Pragma.cpp
@@ -54,11 +54,11 @@ PragmaNamespace::~PragmaNamespace() {
 /// specified name.  If not, return the handler for the null identifier if it
 /// exists, otherwise return null.  If IgnoreNull is true (the default) then
 /// the null handler isn't returned on failure to match.
-PragmaHandler *PragmaNamespace::FindHandler(llvm::StringRef Name,
+PragmaHandler *PragmaNamespace::FindHandler(StringRef Name,
                                             bool IgnoreNull) const {
   if (PragmaHandler *Handler = Handlers.lookup(Name))
     return Handler;
-  return IgnoreNull ? 0 : Handlers.lookup(llvm::StringRef());
+  return IgnoreNull ? 0 : Handlers.lookup(StringRef());
 }
 
 void PragmaNamespace::AddPragma(PragmaHandler *Handler) {
@@ -85,7 +85,7 @@ void PragmaNamespace::HandlePragma(Preprocessor &PP,
   // Get the handler for this token.  If there is no handler, ignore the pragma.
   PragmaHandler *Handler
     = FindHandler(Tok.getIdentifierInfo() ? Tok.getIdentifierInfo()->getName()
-                                          : llvm::StringRef(),
+                                          : StringRef(),
                   /*IgnoreNull=*/false);
   if (Handler == 0) {
     PP.Diag(Tok, diag::warn_pragma_ignored);
@@ -210,7 +210,7 @@ void Preprocessor::HandleMicrosoft__pragma(Token &Tok) {
   }
 
   // Get the tokens enclosed within the __pragma(), as well as the final ')'.
-  llvm::SmallVector<Token, 32> PragmaToks;
+  SmallVector<Token, 32> PragmaToks;
   int NumParens = 0;
   Lex(Tok);
   while (Tok.isNot(tok::eof)) {
@@ -353,7 +353,7 @@ void Preprocessor::HandlePragmaDependency(Token &DependencyTok) {
   // Reserve a buffer to get the spelling.
   llvm::SmallString<128> FilenameBuffer;
   bool Invalid = false;
-  llvm::StringRef Filename = getSpelling(FilenameTok, FilenameBuffer, &Invalid);
+  StringRef Filename = getSpelling(FilenameTok, FilenameBuffer, &Invalid);
   if (Invalid)
     return;
 
@@ -366,9 +366,11 @@ void Preprocessor::HandlePragmaDependency(Token &DependencyTok) {
 
   // Search include directories for this file.
   const DirectoryLookup *CurDir;
-  const FileEntry *File = LookupFile(Filename, isAngled, 0, CurDir, NULL, NULL);
+  const FileEntry *File = LookupFile(Filename, isAngled, 0, CurDir, NULL, NULL,
+                                     NULL);
   if (File == 0) {
-    Diag(FilenameTok, diag::warn_pp_file_not_found) << Filename;
+    if (!SuppressIncludeNotFoundError)
+      Diag(FilenameTok, diag::err_pp_file_not_found) << Filename;
     return;
   }
 
@@ -436,7 +438,7 @@ void Preprocessor::HandlePragmaComment(Token &Tok) {
     // String concatenation allows multiple strings, which can even come from
     // macro expansion.
     // "foo " "bar" "Baz"
-    llvm::SmallVector<Token, 4> StrToks;
+    SmallVector<Token, 4> StrToks;
     while (Tok.is(tok::string_literal)) {
       StrToks.push_back(Tok);
       Lex(Tok);
@@ -444,7 +446,7 @@ void Preprocessor::HandlePragmaComment(Token &Tok) {
 
     // Concatenate and parse the strings.
     StringLiteralParser Literal(&StrToks[0], StrToks.size(), *this);
-    assert(!Literal.AnyWide && "Didn't allow wide strings in");
+    assert(Literal.isAscii() && "Didn't allow wide strings in");
     if (Literal.hadError)
       return;
     if (Literal.Pascal) {
@@ -512,7 +514,7 @@ void Preprocessor::HandlePragmaMessage(Token &Tok) {
   // String concatenation allows multiple strings, which can even come from
   // macro expansion.
   // "foo " "bar" "Baz"
-  llvm::SmallVector<Token, 4> StrToks;
+  SmallVector<Token, 4> StrToks;
   while (Tok.is(tok::string_literal)) {
     StrToks.push_back(Tok);
     Lex(Tok);
@@ -520,7 +522,7 @@ void Preprocessor::HandlePragmaMessage(Token &Tok) {
 
   // Concatenate and parse the strings.
   StringLiteralParser Literal(&StrToks[0], StrToks.size(), *this);
-  assert(!Literal.AnyWide && "Didn't allow wide strings in");
+  assert(Literal.isAscii() && "Didn't allow wide strings in");
   if (Literal.hadError)
     return;
   if (Literal.Pascal) {
@@ -528,7 +530,7 @@ void Preprocessor::HandlePragmaMessage(Token &Tok) {
     return;
   }
 
-  llvm::StringRef MessageString(Literal.GetString());
+  StringRef MessageString(Literal.GetString());
 
   if (ExpectClosingParen) {
     if (Tok.isNot(tok::r_paren)) {
@@ -662,7 +664,7 @@ void Preprocessor::HandlePragmaPopMacro(Token &PopMacroTok) {
 /// AddPragmaHandler - Add the specified pragma handler to the preprocessor.
 /// If 'Namespace' is non-null, then it is a token required to exist on the
 /// pragma line before the pragma string starts, e.g. "STDC" or "GCC".
-void Preprocessor::AddPragmaHandler(llvm::StringRef Namespace,
+void Preprocessor::AddPragmaHandler(StringRef Namespace,
                                     PragmaHandler *Handler) {
   PragmaNamespace *InsertNS = PragmaHandlers;
 
@@ -693,7 +695,7 @@ void Preprocessor::AddPragmaHandler(llvm::StringRef Namespace,
 /// preprocessor. If \arg Namespace is non-null, then it should be the
 /// namespace that \arg Handler was added to. It is an error to remove
 /// a handler that has not been registered.
-void Preprocessor::RemovePragmaHandler(llvm::StringRef Namespace,
+void Preprocessor::RemovePragmaHandler(StringRef Namespace,
                                        PragmaHandler *Handler) {
   PragmaNamespace *NS = PragmaHandlers;
 
@@ -802,7 +804,7 @@ struct PragmaDebugHandler : public PragmaHandler {
     IdentifierInfo *II = Tok.getIdentifierInfo();
 
     if (II->isStr("assert")) {
-      assert(0 && "This is an assertion!");
+      llvm_unreachable("This is an assertion!");
     } else if (II->isStr("crash")) {
       *(volatile int*) 0x11 = 0;
     } else if (II->isStr("llvm_fatal_error")) {
@@ -889,7 +891,7 @@ public:
     // String concatenation allows multiple strings, which can even come from
     // macro expansion.
     // "foo " "bar" "Baz"
-    llvm::SmallVector<Token, 4> StrToks;
+    SmallVector<Token, 4> StrToks;
     while (Tok.is(tok::string_literal)) {
       StrToks.push_back(Tok);
       PP.LexUnexpandedToken(Tok);
@@ -902,7 +904,7 @@ public:
 
     // Concatenate and parse the strings.
     StringLiteralParser Literal(&StrToks[0], StrToks.size(), PP);
-    assert(!Literal.AnyWide && "Didn't allow wide strings in");
+    assert(Literal.isAscii() && "Didn't allow wide strings in");
     if (Literal.hadError)
       return;
     if (Literal.Pascal) {
@@ -910,7 +912,7 @@ public:
       return;
     }
 
-    llvm::StringRef WarningName(Literal.GetString());
+    StringRef WarningName(Literal.GetString());
 
     if (WarningName.size() < 3 || WarningName[0] != '-' ||
         WarningName[1] != 'W') {
@@ -1003,6 +1005,60 @@ struct PragmaSTDC_UnknownHandler : public PragmaHandler {
   }
 };
 
+/// PragmaARCCFCodeAuditedHandler - 
+///   #pragma clang arc_cf_code_audited begin/end
+struct PragmaARCCFCodeAuditedHandler : public PragmaHandler {
+  PragmaARCCFCodeAuditedHandler() : PragmaHandler("arc_cf_code_audited") {}
+  virtual void HandlePragma(Preprocessor &PP, PragmaIntroducerKind Introducer,
+                            Token &NameTok) {
+    SourceLocation Loc = NameTok.getLocation();
+    bool IsBegin;
+
+    Token Tok;
+
+    // Lex the 'begin' or 'end'.
+    PP.LexUnexpandedToken(Tok);
+    const IdentifierInfo *BeginEnd = Tok.getIdentifierInfo();
+    if (BeginEnd && BeginEnd->isStr("begin")) {
+      IsBegin = true;
+    } else if (BeginEnd && BeginEnd->isStr("end")) {
+      IsBegin = false;
+    } else {
+      PP.Diag(Tok.getLocation(), diag::err_pp_arc_cf_code_audited_syntax);
+      return;
+    }
+
+    // Verify that this is followed by EOD.
+    PP.LexUnexpandedToken(Tok);
+    if (Tok.isNot(tok::eod))
+      PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma";
+
+    // The start location of the active audit.
+    SourceLocation BeginLoc = PP.getPragmaARCCFCodeAuditedLoc();
+
+    // The start location we want after processing this.
+    SourceLocation NewLoc;
+
+    if (IsBegin) {
+      // Complain about attempts to re-enter an audit.
+      if (BeginLoc.isValid()) {
+        PP.Diag(Loc, diag::err_pp_double_begin_of_arc_cf_code_audited);
+        PP.Diag(BeginLoc, diag::note_pragma_entered_here);
+      }
+      NewLoc = Loc;
+    } else {
+      // Complain about attempts to leave an audit that doesn't exist.
+      if (!BeginLoc.isValid()) {
+        PP.Diag(Loc, diag::err_pp_unmatched_end_of_arc_cf_code_audited);
+        return;
+      }
+      NewLoc = SourceLocation();
+    }
+
+    PP.setPragmaARCCFCodeAuditedLoc(NewLoc);
+  }
+};
+
 }  // end anonymous namespace
 
 
@@ -1026,13 +1082,14 @@ void Preprocessor::RegisterBuiltinPragmas() {
   AddPragmaHandler("clang", new PragmaDebugHandler());
   AddPragmaHandler("clang", new PragmaDependencyHandler());
   AddPragmaHandler("clang", new PragmaDiagnosticHandler("clang"));
+  AddPragmaHandler("clang", new PragmaARCCFCodeAuditedHandler());
 
   AddPragmaHandler("STDC", new PragmaSTDC_FENV_ACCESSHandler());
   AddPragmaHandler("STDC", new PragmaSTDC_CX_LIMITED_RANGEHandler());
   AddPragmaHandler("STDC", new PragmaSTDC_UnknownHandler());
 
   // MS extensions.
-  if (Features.Microsoft) {
+  if (Features.MicrosoftExt) {
     AddPragmaHandler(new PragmaCommentHandler());
   }
 }
diff --git a/lib/Lex/PreprocessingRecord.cpp b/lib/Lex/PreprocessingRecord.cpp
index 9f93ab04502a..2816609d5f8f 100644
--- a/lib/Lex/PreprocessingRecord.cpp
+++ b/lib/Lex/PreprocessingRecord.cpp
@@ -14,8 +14,8 @@
 #include "clang/Lex/PreprocessingRecord.h"
 #include "clang/Lex/MacroInfo.h"
 #include "clang/Lex/Token.h"
-#include "clang/Basic/IdentifierTable.h"
 #include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/Capacity.h"
 
 using namespace clang;
 
@@ -24,7 +24,7 @@ ExternalPreprocessingRecordSource::~ExternalPreprocessingRecordSource() { }
 
 InclusionDirective::InclusionDirective(PreprocessingRecord &PPRec,
                                        InclusionKind Kind, 
-                                       llvm::StringRef FileName, 
+                                       StringRef FileName, 
                                        bool InQuotes, const FileEntry *File, 
                                        SourceRange Range)
   : PreprocessingDirective(InclusionDirectiveKind, Range), 
@@ -34,116 +34,254 @@ InclusionDirective::InclusionDirective(PreprocessingRecord &PPRec,
     = (char*)PPRec.Allocate(FileName.size() + 1, llvm::alignOf<char>());
   memcpy(Memory, FileName.data(), FileName.size());
   Memory[FileName.size()] = 0;
-  this->FileName = llvm::StringRef(Memory, FileName.size());
+  this->FileName = StringRef(Memory, FileName.size());
 }
 
-void PreprocessingRecord::MaybeLoadPreallocatedEntities() const {
-  if (!ExternalSource || LoadedPreallocatedEntities)
-    return;
-  
-  LoadedPreallocatedEntities = true;
-  ExternalSource->ReadPreprocessedEntities();
+PreprocessingRecord::PreprocessingRecord(SourceManager &SM,
+                                         bool IncludeNestedMacroExpansions)
+  : SourceMgr(SM), IncludeNestedMacroExpansions(IncludeNestedMacroExpansions),
+    ExternalSource(0)
+{
 }
 
-PreprocessingRecord::PreprocessingRecord(bool IncludeNestedMacroExpansions)
-  : IncludeNestedMacroExpansions(IncludeNestedMacroExpansions),
-    ExternalSource(0), NumPreallocatedEntities(0), 
-    LoadedPreallocatedEntities(false)
-{
+/// \brief Returns a pair of [Begin, End) iterators of preprocessed entities
+/// that source range \arg R encompasses.
+std::pair<PreprocessingRecord::iterator, PreprocessingRecord::iterator>
+PreprocessingRecord::getPreprocessedEntitiesInRange(SourceRange Range) {
+  if (Range.isInvalid())
+    return std::make_pair(iterator(this, 0), iterator(this, 0));
+  assert(!SourceMgr.isBeforeInTranslationUnit(Range.getEnd(),Range.getBegin()));
+
+  std::pair<unsigned, unsigned>
+    Local = findLocalPreprocessedEntitiesInRange(Range);
+
+  // Check if range spans local entities.
+  if (!ExternalSource || SourceMgr.isLocalSourceLocation(Range.getBegin()))
+    return std::make_pair(iterator(this, Local.first),
+                          iterator(this, Local.second));
+
+  std::pair<unsigned, unsigned>
+    Loaded = ExternalSource->findPreprocessedEntitiesInRange(Range);
+
+  // Check if range spans local entities.
+  if (Loaded.first == Loaded.second)
+    return std::make_pair(iterator(this, Local.first),
+                          iterator(this, Local.second));
+
+  unsigned TotalLoaded = LoadedPreprocessedEntities.size();
+
+  // Check if range spans loaded entities.
+  if (Local.first == Local.second)
+    return std::make_pair(iterator(this, int(Loaded.first)-TotalLoaded),
+                          iterator(this, int(Loaded.second)-TotalLoaded));
+
+  // Range spands loaded and local entities.
+  return std::make_pair(iterator(this, int(Loaded.first)-TotalLoaded),
+                        iterator(this, Local.second));
 }
 
-PreprocessingRecord::iterator 
-PreprocessingRecord::begin(bool OnlyLocalEntities) {
-  if (OnlyLocalEntities)
-    return PreprocessedEntities.begin() + NumPreallocatedEntities;
-  
-  MaybeLoadPreallocatedEntities();
-  return PreprocessedEntities.begin();
+std::pair<unsigned, unsigned>
+PreprocessingRecord::findLocalPreprocessedEntitiesInRange(
+                                                      SourceRange Range) const {
+  if (Range.isInvalid())
+    return std::make_pair(0,0);
+  assert(!SourceMgr.isBeforeInTranslationUnit(Range.getEnd(),Range.getBegin()));
+
+  unsigned Begin = findBeginLocalPreprocessedEntity(Range.getBegin());
+  unsigned End = findEndLocalPreprocessedEntity(Range.getEnd());
+  return std::make_pair(Begin, End);
 }
 
-PreprocessingRecord::iterator PreprocessingRecord::end(bool OnlyLocalEntities) {
-  if (!OnlyLocalEntities)
-    MaybeLoadPreallocatedEntities();
-  
-  return PreprocessedEntities.end();
+namespace {
+
+template <SourceLocation (SourceRange::*getRangeLoc)() const>
+struct PPEntityComp {
+  const SourceManager &SM;
+
+  explicit PPEntityComp(const SourceManager &SM) : SM(SM) { }
+
+  bool operator()(PreprocessedEntity *L, PreprocessedEntity *R) const {
+    SourceLocation LHS = getLoc(L);
+    SourceLocation RHS = getLoc(R);
+    return SM.isBeforeInTranslationUnit(LHS, RHS);
+  }
+
+  bool operator()(PreprocessedEntity *L, SourceLocation RHS) const {
+    SourceLocation LHS = getLoc(L);
+    return SM.isBeforeInTranslationUnit(LHS, RHS);
+  }
+
+  bool operator()(SourceLocation LHS, PreprocessedEntity *R) const {
+    SourceLocation RHS = getLoc(R);
+    return SM.isBeforeInTranslationUnit(LHS, RHS);
+  }
+
+  SourceLocation getLoc(PreprocessedEntity *PPE) const {
+    SourceRange Range = PPE->getSourceRange();
+    return (Range.*getRangeLoc)();
+  }
+};
+
 }
 
-PreprocessingRecord::const_iterator 
-PreprocessingRecord::begin(bool OnlyLocalEntities) const {
-  if (OnlyLocalEntities)
-    return PreprocessedEntities.begin() + NumPreallocatedEntities;
-  
-  MaybeLoadPreallocatedEntities();
-  return PreprocessedEntities.begin();
+unsigned PreprocessingRecord::findBeginLocalPreprocessedEntity(
+                                                     SourceLocation Loc) const {
+  if (SourceMgr.isLoadedSourceLocation(Loc))
+    return 0;
+
+  size_t Count = PreprocessedEntities.size();
+  size_t Half;
+  std::vector<PreprocessedEntity *>::const_iterator
+    First = PreprocessedEntities.begin();
+  std::vector<PreprocessedEntity *>::const_iterator I;
+
+  // Do a binary search manually instead of using std::lower_bound because
+  // The end locations of entities may be unordered (when a macro expansion
+  // is inside another macro argument), but for this case it is not important
+  // whether we get the first macro expansion or its containing macro.
+  while (Count > 0) {
+    Half = Count/2;
+    I = First;
+    std::advance(I, Half);
+    if (SourceMgr.isBeforeInTranslationUnit((*I)->getSourceRange().getEnd(),
+                                            Loc)){
+      First = I;
+      ++First;
+      Count = Count - Half - 1;
+    } else
+      Count = Half;
+  }
+
+  return First - PreprocessedEntities.begin();
 }
 
-PreprocessingRecord::const_iterator 
-PreprocessingRecord::end(bool OnlyLocalEntities) const {
-  if (!OnlyLocalEntities)
-    MaybeLoadPreallocatedEntities();
-  
-  return PreprocessedEntities.end();
+unsigned PreprocessingRecord::findEndLocalPreprocessedEntity(
+                                                     SourceLocation Loc) const {
+  if (SourceMgr.isLoadedSourceLocation(Loc))
+    return 0;
+
+  std::vector<PreprocessedEntity *>::const_iterator
+  I = std::upper_bound(PreprocessedEntities.begin(),
+                       PreprocessedEntities.end(),
+                       Loc,
+                       PPEntityComp<&SourceRange::getBegin>(SourceMgr));
+  return I - PreprocessedEntities.begin();
 }
 
 void PreprocessingRecord::addPreprocessedEntity(PreprocessedEntity *Entity) {
-  PreprocessedEntities.push_back(Entity);
+  assert(Entity);
+  SourceLocation BeginLoc = Entity->getSourceRange().getBegin();
+  
+  // Check normal case, this entity begin location is after the previous one.
+  if (PreprocessedEntities.empty() ||
+      !SourceMgr.isBeforeInTranslationUnit(BeginLoc,
+                   PreprocessedEntities.back()->getSourceRange().getBegin())) {
+    PreprocessedEntities.push_back(Entity);
+    return;
+  }
+
+  // The entity's location is not after the previous one; this can happen rarely
+  // e.g. with "#include MACRO".
+  // Iterate the entities vector in reverse until we find the right place to
+  // insert the new entity.
+  for (std::vector<PreprocessedEntity *>::iterator
+         RI = PreprocessedEntities.end(), Begin = PreprocessedEntities.begin();
+       RI != Begin; --RI) {
+    std::vector<PreprocessedEntity *>::iterator I = RI;
+    --I;
+    if (!SourceMgr.isBeforeInTranslationUnit(BeginLoc,
+                                           (*I)->getSourceRange().getBegin())) {
+      PreprocessedEntities.insert(RI, Entity);
+      return;
+    }
+  }
 }
 
 void PreprocessingRecord::SetExternalSource(
-                                    ExternalPreprocessingRecordSource &Source,
-                                            unsigned NumPreallocatedEntities) {
+                                    ExternalPreprocessingRecordSource &Source) {
   assert(!ExternalSource &&
          "Preprocessing record already has an external source");
   ExternalSource = &Source;
-  this->NumPreallocatedEntities = NumPreallocatedEntities;
-  PreprocessedEntities.insert(PreprocessedEntities.begin(), 
-                              NumPreallocatedEntities, 0);
 }
 
-void PreprocessingRecord::SetPreallocatedEntity(unsigned Index, 
-                                                PreprocessedEntity *Entity) {
-  assert(Index < NumPreallocatedEntities &&"Out-of-bounds preallocated entity");
-  PreprocessedEntities[Index] = Entity;
+unsigned PreprocessingRecord::allocateLoadedEntities(unsigned NumEntities) {
+  unsigned Result = LoadedPreprocessedEntities.size();
+  LoadedPreprocessedEntities.resize(LoadedPreprocessedEntities.size() 
+                                    + NumEntities);
+  return Result;
+}
+
+void PreprocessingRecord::RegisterMacroDefinition(MacroInfo *Macro,
+                                                  PPEntityID PPID) {
+  MacroDefinitions[Macro] = PPID;
+}
+
+/// \brief Retrieve the preprocessed entity at the given ID.
+PreprocessedEntity *PreprocessingRecord::getPreprocessedEntity(PPEntityID PPID){
+  if (PPID < 0) {
+    assert(unsigned(-PPID-1) < LoadedPreprocessedEntities.size() &&
+           "Out-of bounds loaded preprocessed entity");
+    return getLoadedPreprocessedEntity(LoadedPreprocessedEntities.size()+PPID);
+  }
+  assert(unsigned(PPID) < PreprocessedEntities.size() &&
+         "Out-of bounds local preprocessed entity");
+  return PreprocessedEntities[PPID];
 }
 
-void PreprocessingRecord::RegisterMacroDefinition(MacroInfo *Macro, 
-                                                  MacroDefinition *MD) {
-  MacroDefinitions[Macro] = MD;
+/// \brief Retrieve the loaded preprocessed entity at the given index.
+PreprocessedEntity *
+PreprocessingRecord::getLoadedPreprocessedEntity(unsigned Index) {
+  assert(Index < LoadedPreprocessedEntities.size() && 
+         "Out-of bounds loaded preprocessed entity");
+  assert(ExternalSource && "No external source to load from");
+  PreprocessedEntity *&Entity = LoadedPreprocessedEntities[Index];
+  if (!Entity) {
+    Entity = ExternalSource->ReadPreprocessedEntity(Index);
+    if (!Entity) // Failed to load.
+      Entity = new (*this)
+         PreprocessedEntity(PreprocessedEntity::InvalidKind, SourceRange());
+  }
+  return Entity;
 }
 
 MacroDefinition *PreprocessingRecord::findMacroDefinition(const MacroInfo *MI) {
-  llvm::DenseMap<const MacroInfo *, MacroDefinition *>::iterator Pos
+  llvm::DenseMap<const MacroInfo *, PPEntityID>::iterator Pos
     = MacroDefinitions.find(MI);
   if (Pos == MacroDefinitions.end())
     return 0;
   
-  return Pos->second;
+  PreprocessedEntity *Entity = getPreprocessedEntity(Pos->second);
+  if (Entity->isInvalid())
+    return 0;
+  return cast<MacroDefinition>(Entity);
 }
 
-void PreprocessingRecord::MacroExpands(const Token &Id, const MacroInfo* MI) {
+void PreprocessingRecord::MacroExpands(const Token &Id, const MacroInfo* MI,
+                                       SourceRange Range) {
   if (!IncludeNestedMacroExpansions && Id.getLocation().isMacroID())
     return;
 
-  if (MacroDefinition *Def = findMacroDefinition(MI))
-    PreprocessedEntities.push_back(
-                       new (*this) MacroExpansion(Id.getIdentifierInfo(),
-                                                  Id.getLocation(), Def));
+  if (MI->isBuiltinMacro())
+    addPreprocessedEntity(
+                      new (*this) MacroExpansion(Id.getIdentifierInfo(),Range));
+  else if (MacroDefinition *Def = findMacroDefinition(MI))
+    addPreprocessedEntity(
+                       new (*this) MacroExpansion(Def, Range));
 }
 
 void PreprocessingRecord::MacroDefined(const Token &Id,
                                        const MacroInfo *MI) {
   SourceRange R(MI->getDefinitionLoc(), MI->getDefinitionEndLoc());
   MacroDefinition *Def
-      = new (*this) MacroDefinition(Id.getIdentifierInfo(),
-                                    MI->getDefinitionLoc(),
-                                    R);
-  MacroDefinitions[MI] = Def;
-  PreprocessedEntities.push_back(Def);
+      = new (*this) MacroDefinition(Id.getIdentifierInfo(), R);
+  addPreprocessedEntity(Def);
+  MacroDefinitions[MI] = getPPEntityID(PreprocessedEntities.size()-1,
+                                       /*isLoaded=*/false);
 }
 
 void PreprocessingRecord::MacroUndefined(const Token &Id,
                                          const MacroInfo *MI) {
-  llvm::DenseMap<const MacroInfo *, MacroDefinition *>::iterator Pos
+  llvm::DenseMap<const MacroInfo *, PPEntityID>::iterator Pos
     = MacroDefinitions.find(MI);
   if (Pos != MacroDefinitions.end())
     MacroDefinitions.erase(Pos);
@@ -152,12 +290,12 @@ void PreprocessingRecord::MacroUndefined(const Token &Id,
 void PreprocessingRecord::InclusionDirective(
     SourceLocation HashLoc,
     const clang::Token &IncludeTok,
-    llvm::StringRef FileName,
+    StringRef FileName,
     bool IsAngled,
     const FileEntry *File,
     clang::SourceLocation EndLoc,
-    llvm::StringRef SearchPath,
-    llvm::StringRef RelativePath) {
+    StringRef SearchPath,
+    StringRef RelativePath) {
   InclusionDirective::InclusionKind Kind = InclusionDirective::Include;
   
   switch (IncludeTok.getIdentifierInfo()->getPPKeywordID()) {
@@ -185,5 +323,12 @@ void PreprocessingRecord::InclusionDirective(
   clang::InclusionDirective *ID
     = new (*this) clang::InclusionDirective(*this, Kind, FileName, !IsAngled, 
                                             File, SourceRange(HashLoc, EndLoc));
-  PreprocessedEntities.push_back(ID);
+  addPreprocessedEntity(ID);
+}
+
+size_t PreprocessingRecord::getTotalMemory() const {
+  return BumpAlloc.getTotalMemory()
+    + llvm::capacity_in_bytes(MacroDefinitions)
+    + llvm::capacity_in_bytes(PreprocessedEntities)
+    + llvm::capacity_in_bytes(LoadedPreprocessedEntities);
 }
diff --git a/lib/Lex/Preprocessor.cpp b/lib/Lex/Preprocessor.cpp
index e7aa286a16bf..31662ad0c116 100644
--- a/lib/Lex/Preprocessor.cpp
+++ b/lib/Lex/Preprocessor.cpp
@@ -35,6 +35,7 @@
 #include "clang/Lex/ScratchBuffer.h"
 #include "clang/Lex/LexDiagnostic.h"
 #include "clang/Lex/CodeCompletionHandler.h"
+#include "clang/Lex/ModuleLoader.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Basic/FileManager.h"
 #include "clang/Basic/TargetInfo.h"
@@ -42,27 +43,83 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/Capacity.h"
 using namespace clang;
 
 //===----------------------------------------------------------------------===//
 ExternalPreprocessorSource::~ExternalPreprocessorSource() { }
 
-Preprocessor::Preprocessor(Diagnostic &diags, const LangOptions &opts,
-                           const TargetInfo &target, SourceManager &SM,
-                           HeaderSearch &Headers,
+Preprocessor::Preprocessor(DiagnosticsEngine &diags, LangOptions &opts,
+                           const TargetInfo *target, SourceManager &SM,
+                           HeaderSearch &Headers, ModuleLoader &TheModuleLoader,
                            IdentifierInfoLookup* IILookup,
-                           bool OwnsHeaders)
+                           bool OwnsHeaders,
+                           bool DelayInitialization)
   : Diags(&diags), Features(opts), Target(target),FileMgr(Headers.getFileMgr()),
-    SourceMgr(SM),
-    HeaderInfo(Headers), ExternalSource(0),
-    Identifiers(opts, IILookup), BuiltinInfo(Target), CodeComplete(0),
-    CodeCompletionFile(0), SkipMainFilePreamble(0, true), CurPPLexer(0), 
-    CurDirLookup(0), Callbacks(0), MacroArgCache(0), Record(0), MIChainHead(0),
-    MICache(0) {
-  ScratchBuf = new ScratchBuffer(SourceMgr);
-  CounterValue = 0; // __COUNTER__ starts at 0.
+    SourceMgr(SM), HeaderInfo(Headers), TheModuleLoader(TheModuleLoader),
+    ExternalSource(0), 
+    Identifiers(opts, IILookup), CodeComplete(0),
+    CodeCompletionFile(0), CodeCompletionOffset(0), CodeCompletionReached(0),
+    SkipMainFilePreamble(0, true), CurPPLexer(0), 
+    CurDirLookup(0), CurLexerKind(CLK_Lexer), Callbacks(0), MacroArgCache(0), 
+    Record(0), MIChainHead(0), MICache(0) 
+{
   OwnsHeaderSearch = OwnsHeaders;
+  
+  if (!DelayInitialization) {
+    assert(Target && "Must provide target information for PP initialization");
+    Initialize(*Target);
+  }
+}
+
+Preprocessor::~Preprocessor() {
+  assert(BacktrackPositions.empty() && "EnableBacktrack/Backtrack imbalance!");
+  assert(((MacroExpandingLexersStack.empty() && MacroExpandedTokens.empty()) ||
+          isCodeCompletionReached()) &&
+         "Preprocessor::HandleEndOfTokenLexer should have cleared those");
+
+  while (!IncludeMacroStack.empty()) {
+    delete IncludeMacroStack.back().TheLexer;
+    delete IncludeMacroStack.back().TheTokenLexer;
+    IncludeMacroStack.pop_back();
+  }
 
+  // Free any macro definitions.
+  for (MacroInfoChain *I = MIChainHead ; I ; I = I->Next)
+    I->MI.Destroy();
+
+  // Free any cached macro expanders.
+  for (unsigned i = 0, e = NumCachedTokenLexers; i != e; ++i)
+    delete TokenLexerCache[i];
+
+  // Free any cached MacroArgs.
+  for (MacroArgs *ArgList = MacroArgCache; ArgList; )
+    ArgList = ArgList->deallocate();
+
+  // Release pragma information.
+  delete PragmaHandlers;
+
+  // Delete the scratch buffer info.
+  delete ScratchBuf;
+
+  // Delete the header search info, if we own it.
+  if (OwnsHeaderSearch)
+    delete &HeaderInfo;
+
+  delete Callbacks;
+}
+
+void Preprocessor::Initialize(const TargetInfo &Target) {
+  assert((!this->Target || this->Target == &Target) &&
+         "Invalid override of target information");
+  this->Target = &Target;
+  
+  // Initialize information about built-ins.
+  BuiltinInfo.InitializeTarget(Target);
+  
+  ScratchBuf = new ScratchBuffer(SourceMgr);
+  CounterValue = 0; // __COUNTER__ starts at 0.
+  
   // Clear stats.
   NumDirectives = NumDefined = NumUndefined = NumPragma = 0;
   NumIf = NumElse = NumEndif = 0;
@@ -71,33 +128,35 @@ Preprocessor::Preprocessor(Diagnostic &diags, const LangOptions &opts,
   NumFastMacroExpanded = NumTokenPaste = NumFastTokenPaste = 0;
   MaxIncludeStackDepth = 0;
   NumSkipped = 0;
-
+  
   // Default to discarding comments.
   KeepComments = false;
   KeepMacroComments = false;
-
+  SuppressIncludeNotFoundError = false;
+  AutoModuleImport = false;
+  
   // Macro expansion is enabled.
   DisableMacroExpansion = false;
   InMacroArgs = false;
   NumCachedTokenLexers = 0;
-
+  
   CachedLexPos = 0;
-
+  
   // We haven't read anything from the external source.
   ReadMacrosFromExternalSource = false;
-
+  
   // "Poison" __VA_ARGS__, which can only appear in the expansion of a macro.
   // This gets unpoisoned where it is allowed.
   (Ident__VA_ARGS__ = getIdentifierInfo("__VA_ARGS__"))->setIsPoisoned();
   SetPoisonReason(Ident__VA_ARGS__,diag::ext_pp_bad_vaargs_use);
-
+  
   // Initialize the pragma handlers.
-  PragmaHandlers = new PragmaNamespace(llvm::StringRef());
+  PragmaHandlers = new PragmaNamespace(StringRef());
   RegisterBuiltinPragmas();
-
+  
   // Initialize builtin macros like __LINE__ and friends.
   RegisterBuiltinMacros();
-
+  
   if(Features.Borland) {
     Ident__exception_info        = getIdentifierInfo("_exception_info");
     Ident___exception_info       = getIdentifierInfo("__exception_info");
@@ -112,44 +171,7 @@ Preprocessor::Preprocessor(Diagnostic &diags, const LangOptions &opts,
     Ident__exception_info = Ident__exception_code = Ident__abnormal_termination = 0;
     Ident___exception_info = Ident___exception_code = Ident___abnormal_termination = 0;
     Ident_GetExceptionInfo = Ident_GetExceptionCode = Ident_AbnormalTermination = 0;
-  }
-
-}
-
-Preprocessor::~Preprocessor() {
-  assert(BacktrackPositions.empty() && "EnableBacktrack/Backtrack imbalance!");
-  assert(MacroExpandingLexersStack.empty() && MacroExpandedTokens.empty() &&
-         "Preprocessor::HandleEndOfTokenLexer should have cleared those");
-
-  while (!IncludeMacroStack.empty()) {
-    delete IncludeMacroStack.back().TheLexer;
-    delete IncludeMacroStack.back().TheTokenLexer;
-    IncludeMacroStack.pop_back();
-  }
-
-  // Free any macro definitions.
-  for (MacroInfoChain *I = MIChainHead ; I ; I = I->Next)
-    I->MI.Destroy();
-
-  // Free any cached macro expanders.
-  for (unsigned i = 0, e = NumCachedTokenLexers; i != e; ++i)
-    delete TokenLexerCache[i];
-
-  // Free any cached MacroArgs.
-  for (MacroArgs *ArgList = MacroArgCache; ArgList; )
-    ArgList = ArgList->deallocate();
-
-  // Release pragma information.
-  delete PragmaHandlers;
-
-  // Delete the scratch buffer info.
-  delete ScratchBuf;
-
-  // Delete the header search info, if we own it.
-  if (OwnsHeaderSearch)
-    delete &HeaderInfo;
-
-  delete Callbacks;
+  } 
 }
 
 void Preprocessor::setPTHManager(PTHManager* pm) {
@@ -172,7 +194,7 @@ void Preprocessor::DumpToken(const Token &Tok, bool DumpFlags) const {
     llvm::errs() << " [ExpandDisabled]";
   if (Tok.needsCleaning()) {
     const char *Start = SourceMgr.getCharacterData(Tok.getLocation());
-    llvm::errs() << " [UnClean='" << llvm::StringRef(Start, Tok.getLength())
+    llvm::errs() << " [UnClean='" << StringRef(Start, Tok.getLength())
                  << "']";
   }
 
@@ -228,7 +250,13 @@ Preprocessor::macro_begin(bool IncludeExternalMacros) const {
 }
 
 size_t Preprocessor::getTotalMemory() const {
-  return BP.getTotalMemory() + MacroExpandedTokens.capacity()*sizeof(Token);
+  return BP.getTotalMemory()
+    + llvm::capacity_in_bytes(MacroExpandedTokens)
+    + Predefines.capacity() /* Predefines buffer. */
+    + llvm::capacity_in_bytes(Macros)
+    + llvm::capacity_in_bytes(PragmaPushMacroInfo)
+    + llvm::capacity_in_bytes(PoisonReasons)
+    + llvm::capacity_in_bytes(CommentHandlers);
 }
 
 Preprocessor::macro_iterator
@@ -243,15 +271,13 @@ Preprocessor::macro_end(bool IncludeExternalMacros) const {
 }
 
 bool Preprocessor::SetCodeCompletionPoint(const FileEntry *File,
-                                          unsigned TruncateAtLine,
-                                          unsigned TruncateAtColumn) {
-  using llvm::MemoryBuffer;
-
-  CodeCompletionFile = File;
+                                          unsigned CompleteLine,
+                                          unsigned CompleteColumn) {
+  assert(File);
+  assert(CompleteLine && CompleteColumn && "Starts from 1:1");
+  assert(!CodeCompletionFile && "Already set");
 
-  // Okay to clear out the code-completion point by passing NULL.
-  if (!CodeCompletionFile)
-    return false;
+  using llvm::MemoryBuffer;
 
   // Load the actual file's contents.
   bool Invalid = false;
@@ -261,7 +287,7 @@ bool Preprocessor::SetCodeCompletionPoint(const FileEntry *File,
 
   // Find the byte position of the truncation point.
   const char *Position = Buffer->getBufferStart();
-  for (unsigned Line = 1; Line < TruncateAtLine; ++Line) {
+  for (unsigned Line = 1; Line < CompleteLine; ++Line) {
     for (; *Position; ++Position) {
       if (*Position != '\r' && *Position != '\n')
         continue;
@@ -275,38 +301,37 @@ bool Preprocessor::SetCodeCompletionPoint(const FileEntry *File,
     }
   }
 
-  Position += TruncateAtColumn - 1;
+  Position += CompleteColumn - 1;
 
-  // Truncate the buffer.
+  // Insert '\0' at the code-completion point.
   if (Position < Buffer->getBufferEnd()) {
-    llvm::StringRef Data(Buffer->getBufferStart(),
-                         Position-Buffer->getBufferStart());
-    MemoryBuffer *TruncatedBuffer
-      = MemoryBuffer::getMemBufferCopy(Data, Buffer->getBufferIdentifier());
-    SourceMgr.overrideFileContents(File, TruncatedBuffer);
+    CodeCompletionFile = File;
+    CodeCompletionOffset = Position - Buffer->getBufferStart();
+
+    MemoryBuffer *NewBuffer =
+        MemoryBuffer::getNewUninitMemBuffer(Buffer->getBufferSize() + 1,
+                                            Buffer->getBufferIdentifier());
+    char *NewBuf = const_cast<char*>(NewBuffer->getBufferStart());
+    char *NewPos = std::copy(Buffer->getBufferStart(), Position, NewBuf);
+    *NewPos = '\0';
+    std::copy(Position, Buffer->getBufferEnd(), NewPos+1);
+    SourceMgr.overrideFileContents(File, NewBuffer);
   }
 
   return false;
 }
 
-bool Preprocessor::isCodeCompletionFile(SourceLocation FileLoc) const {
-  return CodeCompletionFile && FileLoc.isFileID() &&
-    SourceMgr.getFileEntryForID(SourceMgr.getFileID(FileLoc))
-      == CodeCompletionFile;
-}
-
 void Preprocessor::CodeCompleteNaturalLanguage() {
-  SetCodeCompletionPoint(0, 0, 0);
-  getDiagnostics().setSuppressAllDiagnostics(true);
   if (CodeComplete)
     CodeComplete->CodeCompleteNaturalLanguage();
+  setCodeCompletionReached();
 }
 
 /// getSpelling - This method is used to get the spelling of a token into a
 /// SmallVector. Note that the returned StringRef may not point to the
 /// supplied buffer if a copy can be avoided.
-llvm::StringRef Preprocessor::getSpelling(const Token &Tok,
-                                          llvm::SmallVectorImpl<char> &Buffer,
+StringRef Preprocessor::getSpelling(const Token &Tok,
+                                          SmallVectorImpl<char> &Buffer,
                                           bool *Invalid) const {
   // NOTE: this has to be checked *before* testing for an IdentifierInfo.
   if (Tok.isNot(tok::raw_identifier)) {
@@ -321,22 +346,23 @@ llvm::StringRef Preprocessor::getSpelling(const Token &Tok,
 
   const char *Ptr = Buffer.data();
   unsigned Len = getSpelling(Tok, Ptr, Invalid);
-  return llvm::StringRef(Ptr, Len);
+  return StringRef(Ptr, Len);
 }
 
 /// CreateString - Plop the specified string into a scratch buffer and return a
 /// location for it.  If specified, the source location provides a source
 /// location for the token.
 void Preprocessor::CreateString(const char *Buf, unsigned Len, Token &Tok,
-                                SourceLocation ExpansionLoc) {
+                                SourceLocation ExpansionLocStart,
+                                SourceLocation ExpansionLocEnd) {
   Tok.setLength(Len);
 
   const char *DestPtr;
   SourceLocation Loc = ScratchBuf->getToken(Buf, Len, DestPtr);
 
-  if (ExpansionLoc.isValid())
-    Loc = SourceMgr.createInstantiationLoc(Loc, ExpansionLoc,
-                                           ExpansionLoc, Len);
+  if (ExpansionLocStart.isValid())
+    Loc = SourceMgr.createExpansionLoc(Loc, ExpansionLocStart,
+                                       ExpansionLocEnd, Len);
   Tok.setLocation(Loc);
 
   // If this is a raw identifier or a literal token, set the pointer data.
@@ -407,12 +433,12 @@ IdentifierInfo *Preprocessor::LookUpIdentifierInfo(Token &Identifier) const {
   IdentifierInfo *II;
   if (!Identifier.needsCleaning()) {
     // No cleaning needed, just use the characters from the lexed buffer.
-    II = getIdentifierInfo(llvm::StringRef(Identifier.getRawIdentifierData(),
+    II = getIdentifierInfo(StringRef(Identifier.getRawIdentifierData(),
                                            Identifier.getLength()));
   } else {
     // Cleaning needed, alloca a buffer, clean into it, then use the buffer.
     llvm::SmallString<64> IdentifierBuffer;
-    llvm::StringRef CleanedStr = getSpelling(Identifier, IdentifierBuffer);
+    StringRef CleanedStr = getSpelling(Identifier, IdentifierBuffer);
     II = getIdentifierInfo(CleanedStr);
   }
 
@@ -487,6 +513,17 @@ void Preprocessor::HandleIdentifier(Token &Identifier) {
     }
   }
 
+  // If this identifier is a keyword in C++11, produce a warning. Don't warn if
+  // we're not considering macro expansion, since this identifier might be the
+  // name of a macro.
+  // FIXME: This warning is disabled in cases where it shouldn't be, like
+  //   "#define constexpr constexpr", "int constexpr;"
+  if (II.isCXX11CompatKeyword() & !DisableMacroExpansion) {
+    Diag(Identifier, diag::warn_cxx11_keyword) << II.getName();
+    // Don't diagnose this keyword again in this translation unit.
+    II.setIsCXX11CompatKeyword(false);
+  }
+
   // C++ 2.11p2: If this is an alternative representation of a C++ operator,
   // then we act as if it is the actual operator and not the textual
   // representation of it.
@@ -499,6 +536,44 @@ void Preprocessor::HandleIdentifier(Token &Identifier) {
   // like "#define TY typeof", "TY(1) x".
   if (II.isExtensionToken() && !DisableMacroExpansion)
     Diag(Identifier, diag::ext_token_used);
+  
+  // If this is the '__import_module__' keyword, note that the next token
+  // indicates a module name.
+  if (II.getTokenID() == tok::kw___import_module__ &&
+      !InMacroArgs && !DisableMacroExpansion) {
+    ModuleImportLoc = Identifier.getLocation();
+    CurLexerKind = CLK_LexAfterModuleImport;
+  }
+}
+
+/// \brief Lex a token following the __import_module__ keyword.
+void Preprocessor::LexAfterModuleImport(Token &Result) {
+  // Figure out what kind of lexer we actually have.
+  if (CurLexer)
+    CurLexerKind = CLK_Lexer;
+  else if (CurPTHLexer)
+    CurLexerKind = CLK_PTHLexer;
+  else if (CurTokenLexer)
+    CurLexerKind = CLK_TokenLexer;
+  else 
+    CurLexerKind = CLK_CachingLexer;
+  
+  // Lex the next token.
+  Lex(Result);
+
+  // The token sequence 
+  //
+  //   __import_module__ identifier
+  //
+  // indicates a module import directive. We already saw the __import_module__
+  // keyword, so now we're looking for the identifier.
+  if (Result.getKind() != tok::identifier)
+    return;
+  
+  // Load the module.
+  (void)TheModuleLoader.loadModule(ModuleImportLoc,
+                                   *Result.getIdentifierInfo(), 
+                                   Result.getLocation());
 }
 
 void Preprocessor::AddCommentHandler(CommentHandler *Handler) {
@@ -529,6 +604,8 @@ bool Preprocessor::HandleComment(Token &result, SourceRange Comment) {
   return true;
 }
 
+ModuleLoader::~ModuleLoader() { }
+
 CommentHandler::~CommentHandler() { }
 
 CodeCompletionHandler::~CodeCompletionHandler() { }
@@ -538,6 +615,7 @@ void Preprocessor::createPreprocessingRecord(
   if (Record)
     return;
   
-  Record = new PreprocessingRecord(IncludeNestedMacroExpansions);
+  Record = new PreprocessingRecord(getSourceManager(),
+                                   IncludeNestedMacroExpansions);
   addPPCallbacks(Record);
 }
diff --git a/lib/Lex/PreprocessorLexer.cpp b/lib/Lex/PreprocessorLexer.cpp
index 808a81bd5e87..0da9ef5531e7 100644
--- a/lib/Lex/PreprocessorLexer.cpp
+++ b/lib/Lex/PreprocessorLexer.cpp
@@ -17,6 +17,14 @@
 #include "clang/Basic/SourceManager.h"
 using namespace clang;
 
+PreprocessorLexer::PreprocessorLexer(Preprocessor *pp, FileID fid)
+  : PP(pp), FID(fid), InitialNumSLocEntries(0),
+    ParsingPreprocessorDirective(false),
+    ParsingFilename(false), LexingRawMode(false) {
+  if (pp)
+    InitialNumSLocEntries = pp->getSourceManager().local_sloc_entry_size();
+}
+
 /// LexIncludeFilename - After the preprocessor has parsed a #include, lex and
 /// (potentially) macro expand the filename.
 void PreprocessorLexer::LexIncludeFilename(Token &FilenameTok) {
diff --git a/lib/Lex/ScratchBuffer.cpp b/lib/Lex/ScratchBuffer.cpp
index 0e98c1751985..3d363fa4b472 100644
--- a/lib/Lex/ScratchBuffer.cpp
+++ b/lib/Lex/ScratchBuffer.cpp
@@ -53,7 +53,7 @@ SourceLocation ScratchBuffer::getToken(const char *Buf, unsigned Len,
   // diagnostic points to one.
   CurBuffer[BytesUsed-1] = '\0';
 
-  return BufferStartLoc.getFileLocWithOffset(BytesUsed-Len-1);
+  return BufferStartLoc.getLocWithOffset(BytesUsed-Len-1);
 }
 
 void ScratchBuffer::AllocScratchBuffer(unsigned RequestLen) {
diff --git a/lib/Lex/TokenConcatenation.cpp b/lib/Lex/TokenConcatenation.cpp
index 3e9e8550313c..dc6d686d6cc1 100644
--- a/lib/Lex/TokenConcatenation.cpp
+++ b/lib/Lex/TokenConcatenation.cpp
@@ -17,42 +17,53 @@
 using namespace clang;
 
 
-/// StartsWithL - Return true if the spelling of this token starts with 'L'.
-bool TokenConcatenation::StartsWithL(const Token &Tok) const {
-  if (!Tok.needsCleaning()) {
-    SourceManager &SM = PP.getSourceManager();
-    return *SM.getCharacterData(SM.getSpellingLoc(Tok.getLocation())) == 'L';
-  }
+/// IsStringPrefix - Return true if Str is a string prefix.
+/// 'L', 'u', 'U', or 'u8'. Including raw versions.
+static bool IsStringPrefix(StringRef Str, bool CPlusPlus0x) {
 
-  if (Tok.getLength() < 256) {
-    char Buffer[256];
-    const char *TokPtr = Buffer;
-    PP.getSpelling(Tok, TokPtr);
-    return TokPtr[0] == 'L';
+  if (Str[0] == 'L' ||
+      (CPlusPlus0x && (Str[0] == 'u' || Str[0] == 'U' || Str[0] == 'R'))) {
+
+    if (Str.size() == 1)
+      return true; // "L", "u", "U", and "R"
+
+    // Check for raw flavors. Need to make sure the first character wasn't
+    // already R. Need CPlusPlus0x check for "LR".
+    if (Str[1] == 'R' && Str[0] != 'R' && Str.size() == 2 && CPlusPlus0x)
+      return true; // "LR", "uR", "UR"
+
+    // Check for "u8" and "u8R"
+    if (Str[0] == 'u' && Str[1] == '8') {
+      if (Str.size() == 2) return true; // "u8"
+      if (Str.size() == 3 && Str[2] == 'R') return true; // "u8R"
+    }
   }
 
-  return PP.getSpelling(Tok)[0] == 'L';
+  return false;
 }
 
-/// IsIdentifierL - Return true if the spelling of this token is literally
-/// 'L'.
-bool TokenConcatenation::IsIdentifierL(const Token &Tok) const {
+/// IsIdentifierStringPrefix - Return true if the spelling of the token
+/// is literally 'L', 'u', 'U', or 'u8'. Including raw versions.
+bool TokenConcatenation::IsIdentifierStringPrefix(const Token &Tok) const {
+  const LangOptions &LangOpts = PP.getLangOptions();
+
   if (!Tok.needsCleaning()) {
-    if (Tok.getLength() != 1)
+    if (Tok.getLength() < 1 || Tok.getLength() > 3)
       return false;
     SourceManager &SM = PP.getSourceManager();
-    return *SM.getCharacterData(SM.getSpellingLoc(Tok.getLocation())) == 'L';
+    const char *Ptr = SM.getCharacterData(SM.getSpellingLoc(Tok.getLocation()));
+    return IsStringPrefix(StringRef(Ptr, Tok.getLength()),
+                          LangOpts.CPlusPlus0x);
   }
 
   if (Tok.getLength() < 256) {
     char Buffer[256];
     const char *TokPtr = Buffer;
-    if (PP.getSpelling(Tok, TokPtr) != 1)
-      return false;
-    return TokPtr[0] == 'L';
+    unsigned length = PP.getSpelling(Tok, TokPtr);
+    return IsStringPrefix(StringRef(TokPtr, length), LangOpts.CPlusPlus0x);
   }
 
-  return PP.getSpelling(Tok) == "L";
+  return IsStringPrefix(StringRef(PP.getSpelling(Tok)), LangOpts.CPlusPlus0x);
 }
 
 TokenConcatenation::TokenConcatenation(Preprocessor &pp) : PP(pp) {
@@ -132,7 +143,7 @@ bool TokenConcatenation::AvoidConcat(const Token &PrevPrevTok,
   // source.  If they were, it must be okay to stick them together: if there
   // were an issue, the tokens would have been lexed differently.
   if (PrevTok.getLocation().isFileID() && Tok.getLocation().isFileID() &&
-      PrevTok.getLocation().getFileLocWithOffset(PrevTok.getLength()) ==
+      PrevTok.getLocation().getLocWithOffset(PrevTok.getLength()) ==
         Tok.getLocation())
     return false;
 
@@ -179,24 +190,19 @@ bool TokenConcatenation::AvoidConcat(const Token &PrevPrevTok,
     if (Tok.is(tok::numeric_constant))
       return GetFirstChar(PP, Tok) != '.';
 
-    if (Tok.getIdentifierInfo() || Tok.is(tok::wide_string_literal) /* ||
-     Tok.is(tok::wide_char_literal)*/)
+    if (Tok.getIdentifierInfo() || Tok.is(tok::wide_string_literal) ||
+        Tok.is(tok::utf8_string_literal) || Tok.is(tok::utf16_string_literal) ||
+        Tok.is(tok::utf32_string_literal) || Tok.is(tok::wide_char_constant) ||
+        Tok.is(tok::utf16_char_constant) || Tok.is(tok::utf32_char_constant))
       return true;
 
     // If this isn't identifier + string, we're done.
     if (Tok.isNot(tok::char_constant) && Tok.isNot(tok::string_literal))
       return false;
 
-    // FIXME: need a wide_char_constant!
-
-    // If the string was a wide string L"foo" or wide char L'f', it would
-    // concat with the previous identifier into fooL"bar".  Avoid this.
-    if (StartsWithL(Tok))
-      return true;
-
     // Otherwise, this is a narrow character or string.  If the *identifier*
-    // is a literal 'L', avoid pasting L "foo" -> L"foo".
-    return IsIdentifierL(PrevTok);
+    // is a literal 'L', 'u8', 'u' or 'U', avoid pasting L "foo" -> L"foo".
+    return IsIdentifierStringPrefix(PrevTok);
   case tok::numeric_constant:
     return isalnum(FirstChar) || Tok.is(tok::numeric_constant) ||
     FirstChar == '+' || FirstChar == '-' || FirstChar == '.';
diff --git a/lib/Lex/TokenLexer.cpp b/lib/Lex/TokenLexer.cpp
index 8ff82f160033..a58054490fcd 100644
--- a/lib/Lex/TokenLexer.cpp
+++ b/lib/Lex/TokenLexer.cpp
@@ -43,7 +43,7 @@ void TokenLexer::Init(Token &Tok, SourceLocation ELEnd, MacroArgs *Actuals) {
   MacroExpansionStart = SourceLocation();
 
   SourceManager &SM = PP.getSourceManager();
-  MacroStartSLocOffset = SM.getNextOffset();
+  MacroStartSLocOffset = SM.getNextLocalOffset();
 
   if (NumTokens > 0) {
     assert(Tokens[0].getLocation().isValid());
@@ -55,12 +55,12 @@ void TokenLexer::Init(Token &Tok, SourceLocation ELEnd, MacroArgs *Actuals) {
     // definition. Tokens that get lexed directly from the definition will
     // have their locations pointing inside this chunk. This is to avoid
     // creating separate source location entries for each token.
-    SourceLocation macroStart = SM.getInstantiationLoc(Tokens[0].getLocation());
-    MacroDefStartInfo = SM.getDecomposedLoc(macroStart);
-    MacroExpansionStart = SM.createInstantiationLoc(macroStart,
-                                              ExpandLocStart,
-                                              ExpandLocEnd,
-                                              Macro->getDefinitionLength(SM));
+    MacroDefStart = SM.getExpansionLoc(Tokens[0].getLocation());
+    MacroDefLength = Macro->getDefinitionLength(SM);
+    MacroExpansionStart = SM.createExpansionLoc(MacroDefStart,
+                                                ExpandLocStart,
+                                                ExpandLocEnd,
+                                                MacroDefLength);
   }
 
   // If this is a function-like macro, expand the arguments and change
@@ -121,9 +121,8 @@ void TokenLexer::destroy() {
 /// Expand the arguments of a function-like macro so that we can quickly
 /// return preexpanded tokens from Tokens.
 void TokenLexer::ExpandFunctionArguments() {
-  SourceManager &SM = PP.getSourceManager();
 
-  llvm::SmallVector<Token, 128> ResultToks;
+  SmallVector<Token, 128> ResultToks;
 
   // Loop through 'Tokens', expanding them into ResultToks.  Keep
   // track of whether we change anything.  If not, no need to keep them.  If so,
@@ -144,19 +143,22 @@ void TokenLexer::ExpandFunctionArguments() {
       int ArgNo = Macro->getArgumentNum(Tokens[i+1].getIdentifierInfo());
       assert(ArgNo != -1 && "Token following # is not an argument?");
 
-      SourceLocation hashInstLoc;
-      if(ExpandLocStart.isValid()) {
-        hashInstLoc = getMacroExpansionLocation(CurTok.getLocation());
-        assert(hashInstLoc.isValid() && "Expected '#' to come from definition");
-      }
+      SourceLocation ExpansionLocStart =
+          getExpansionLocForMacroDefLoc(CurTok.getLocation());
+      SourceLocation ExpansionLocEnd =
+          getExpansionLocForMacroDefLoc(Tokens[i+1].getLocation());
 
       Token Res;
       if (CurTok.is(tok::hash))  // Stringify
-        Res = ActualArgs->getStringifiedArgument(ArgNo, PP, hashInstLoc);
+        Res = ActualArgs->getStringifiedArgument(ArgNo, PP,
+                                                 ExpansionLocStart,
+                                                 ExpansionLocEnd);
       else {
         // 'charify': don't bother caching these.
         Res = MacroArgs::StringifyArgument(ActualArgs->getUnexpArgument(ArgNo),
-                                           PP, true, hashInstLoc);
+                                           PP, true,
+                                           ExpansionLocStart,
+                                           ExpansionLocEnd);
       }
 
       // The stringified/charified string leading space flag gets set to match
@@ -225,16 +227,9 @@ void TokenLexer::ExpandFunctionArguments() {
         }
 
         if(ExpandLocStart.isValid()) {
-          SourceLocation curInst =
-              getMacroExpansionLocation(CurTok.getLocation());
-          assert(curInst.isValid() &&
-                 "Expected arg identifier to come from definition");
-          for (unsigned i = FirstResult, e = ResultToks.size(); i != e; ++i) {
-            Token &Tok = ResultToks[i];
-            Tok.setLocation(SM.createMacroArgInstantiationLoc(Tok.getLocation(),
-                                                              curInst,
-                                                              Tok.getLength()));
-          }
+          updateLocForMacroArgTokens(CurTok.getLocation(),
+                                     ResultToks.begin()+FirstResult,
+                                     ResultToks.end());
         }
 
         // If any tokens were substituted from the argument, the whitespace
@@ -282,17 +277,8 @@ void TokenLexer::ExpandFunctionArguments() {
       }
 
       if (ExpandLocStart.isValid()) {
-        SourceLocation curInst =
-            getMacroExpansionLocation(CurTok.getLocation());
-        assert(curInst.isValid() &&
-               "Expected arg identifier to come from definition");
-        for (unsigned i = ResultToks.size() - NumToks, e = ResultToks.size();
-               i != e; ++i) {
-          Token &Tok = ResultToks[i];
-          Tok.setLocation(SM.createMacroArgInstantiationLoc(Tok.getLocation(),
-                                                            curInst,
-                                                            Tok.getLength()));
-        }
+        updateLocForMacroArgTokens(CurTok.getLocation(),
+                                   ResultToks.end()-NumToks, ResultToks.end());
       }
 
       // If this token (the macro argument) was supposed to get leading
@@ -417,18 +403,15 @@ void TokenLexer::Lex(Token &Tok) {
   // that captures all of this.
   if (ExpandLocStart.isValid() &&   // Don't do this for token streams.
       // Check that the token's location was not already set properly.
-      SM.isBeforeInSourceLocationOffset(Tok.getLocation(),
-                                        MacroStartSLocOffset)) {
+      SM.isBeforeInSLocAddrSpace(Tok.getLocation(), MacroStartSLocOffset)) {
     SourceLocation instLoc;
     if (Tok.is(tok::comment)) {
-      instLoc = SM.createInstantiationLoc(Tok.getLocation(),
-                                          ExpandLocStart,
-                                          ExpandLocEnd,
-                                          Tok.getLength());
+      instLoc = SM.createExpansionLoc(Tok.getLocation(),
+                                      ExpandLocStart,
+                                      ExpandLocEnd,
+                                      Tok.getLength());
     } else {
-      instLoc = getMacroExpansionLocation(Tok.getLocation());
-      assert(instLoc.isValid() &&
-             "Location for token not coming from definition was not set!");
+      instLoc = getExpansionLocForMacroDefLoc(Tok.getLocation());
     }
 
     Tok.setLocation(instLoc);
@@ -469,6 +452,7 @@ void TokenLexer::Lex(Token &Tok) {
 bool TokenLexer::PasteTokens(Token &Tok) {
   llvm::SmallString<128> Buffer;
   const char *ResultTokStrPtr = 0;
+  SourceLocation StartLoc = Tok.getLocation();
   SourceLocation PasteOpLoc;
   do {
     // Consume the ## operator.
@@ -562,7 +546,7 @@ bool TokenLexer::PasteTokens(Token &Tok) {
       if (isInvalid) {
         // Test for the Microsoft extension of /##/ turning into // here on the
         // error path.
-        if (PP.getLangOptions().Microsoft && Tok.is(tok::slash) &&
+        if (PP.getLangOptions().MicrosoftExt && Tok.is(tok::slash) &&
             RHS.is(tok::slash)) {
           HandleMicrosoftCommentPaste(Tok);
           return true;
@@ -574,14 +558,13 @@ bool TokenLexer::PasteTokens(Token &Tok) {
           // information so that the user knows where it came from.
           SourceManager &SM = PP.getSourceManager();
           SourceLocation Loc =
-            SM.createInstantiationLoc(PasteOpLoc, ExpandLocStart,
-                                      ExpandLocEnd, 2);
+            SM.createExpansionLoc(PasteOpLoc, ExpandLocStart, ExpandLocEnd, 2);
           // If we're in microsoft extensions mode, downgrade this from a hard
           // error to a warning that defaults to an error.  This allows
           // disabling it.
           PP.Diag(Loc,
-                  PP.getLangOptions().Microsoft ? diag::err_pp_bad_paste_ms 
-                                                : diag::err_pp_bad_paste)
+                  PP.getLangOptions().MicrosoftExt ? diag::err_pp_bad_paste_ms 
+                                                   : diag::err_pp_bad_paste)
             << Buffer.str();
         }
 
@@ -604,23 +587,20 @@ bool TokenLexer::PasteTokens(Token &Tok) {
     Tok = Result;
   } while (!isAtEnd() && Tokens[CurToken].is(tok::hashhash));
 
+  SourceLocation EndLoc = Tokens[CurToken - 1].getLocation();
+
   // The token's current location indicate where the token was lexed from.  We
   // need this information to compute the spelling of the token, but any
   // diagnostics for the expanded token should appear as if the token was
-  // expanded from the (##) operator. Pull this information together into
+  // expanded from the full ## expression. Pull this information together into
   // a new SourceLocation that captures all of this.
-  if (ExpandLocStart.isValid()) {
-    SourceManager &SM = PP.getSourceManager();
-    SourceLocation pasteLocInst =
-        getMacroExpansionLocation(PasteOpLoc);
-    assert(pasteLocInst.isValid() &&
-           "Expected '##' to come from definition");
-
-    Tok.setLocation(SM.createInstantiationLoc(Tok.getLocation(),
-                                              pasteLocInst,
-                                              pasteLocInst,
-                                              Tok.getLength()));
-  }
+  SourceManager &SM = PP.getSourceManager();
+  if (StartLoc.isFileID())
+    StartLoc = getExpansionLocForMacroDefLoc(StartLoc);
+  if (EndLoc.isFileID())
+    EndLoc = getExpansionLocForMacroDefLoc(EndLoc);
+  Tok.setLocation(SM.createExpansionLoc(Tok.getLocation(), StartLoc, EndLoc,
+                                        Tok.getLength()));
 
   // Now that we got the result token, it will be subject to expansion.  Since
   // token pasting re-lexes the result token in raw mode, identifier information
@@ -666,22 +646,111 @@ void TokenLexer::HandleMicrosoftCommentPaste(Token &Tok) {
   PP.HandleMicrosoftCommentPaste(Tok);
 }
 
-/// \brief If \arg loc is a FileID and points inside the current macro
+/// \brief If \arg loc is a file ID and points inside the current macro
 /// definition, returns the appropriate source location pointing at the
-/// macro expansion source location entry.
-SourceLocation TokenLexer::getMacroExpansionLocation(SourceLocation loc) const {
+/// macro expansion source location entry, otherwise it returns an invalid
+/// SourceLocation.
+SourceLocation
+TokenLexer::getExpansionLocForMacroDefLoc(SourceLocation loc) const {
   assert(ExpandLocStart.isValid() && MacroExpansionStart.isValid() &&
          "Not appropriate for token streams");
-  assert(loc.isValid());
+  assert(loc.isValid() && loc.isFileID());
   
   SourceManager &SM = PP.getSourceManager();
-  unsigned relativeOffset;
-  if (loc.isFileID() &&
-      SM.isInFileID(loc,
-                    MacroDefStartInfo.first, MacroDefStartInfo.second,
-                    Macro->getDefinitionLength(SM), &relativeOffset)) {
-    return MacroExpansionStart.getFileLocWithOffset(relativeOffset);
+  assert(SM.isInSLocAddrSpace(loc, MacroDefStart, MacroDefLength) &&
+         "Expected loc to come from the macro definition");
+
+  unsigned relativeOffset = 0;
+  SM.isInSLocAddrSpace(loc, MacroDefStart, MacroDefLength, &relativeOffset);
+  return MacroExpansionStart.getLocWithOffset(relativeOffset);
+}
+
+/// \brief Finds the tokens that are consecutive (from the same FileID)
+/// creates a single SLocEntry, and assigns SourceLocations to each token that
+/// point to that SLocEntry. e.g for
+///   assert(foo == bar);
+/// There will be a single SLocEntry for the "foo == bar" chunk and locations
+/// for the 'foo', '==', 'bar' tokens will point inside that chunk.
+///
+/// \arg begin_tokens will be updated to a position past all the found
+/// consecutive tokens.
+static void updateConsecutiveMacroArgTokens(SourceManager &SM,
+                                            SourceLocation InstLoc,
+                                            Token *&begin_tokens,
+                                            Token * end_tokens) {
+  assert(begin_tokens < end_tokens);
+
+  SourceLocation FirstLoc = begin_tokens->getLocation();
+  SourceLocation CurLoc = FirstLoc;
+
+  // Compare the source location offset of tokens and group together tokens that
+  // are close, even if their locations point to different FileIDs. e.g.
+  //
+  //  |bar    |  foo | cake   |  (3 tokens from 3 consecutive FileIDs)
+  //  ^                    ^
+  //  |bar       foo   cake|     (one SLocEntry chunk for all tokens)
+  //
+  // we can perform this "merge" since the token's spelling location depends
+  // on the relative offset.
+
+  Token *NextTok = begin_tokens + 1;
+  for (; NextTok < end_tokens; ++NextTok) {
+    int RelOffs;
+    if (!SM.isInSameSLocAddrSpace(CurLoc, NextTok->getLocation(), &RelOffs))
+      break; // Token from different local/loaded location.
+    // Check that token is not before the previous token or more than 50
+    // "characters" away.
+    if (RelOffs < 0 || RelOffs > 50)
+      break;
+    CurLoc = NextTok->getLocation();
   }
 
-  return SourceLocation();
+  // For the consecutive tokens, find the length of the SLocEntry to contain
+  // all of them.
+  Token &LastConsecutiveTok = *(NextTok-1);
+  int LastRelOffs = 0;
+  SM.isInSameSLocAddrSpace(FirstLoc, LastConsecutiveTok.getLocation(),
+                           &LastRelOffs);
+  unsigned FullLength = LastRelOffs + LastConsecutiveTok.getLength();
+
+  // Create a macro expansion SLocEntry that will "contain" all of the tokens.
+  SourceLocation Expansion =
+      SM.createMacroArgExpansionLoc(FirstLoc, InstLoc,FullLength);
+
+  // Change the location of the tokens from the spelling location to the new
+  // expanded location.
+  for (; begin_tokens < NextTok; ++begin_tokens) {
+    Token &Tok = *begin_tokens;
+    int RelOffs = 0;
+    SM.isInSameSLocAddrSpace(FirstLoc, Tok.getLocation(), &RelOffs);
+    Tok.setLocation(Expansion.getLocWithOffset(RelOffs));
+  }
+}
+
+/// \brief Creates SLocEntries and updates the locations of macro argument
+/// tokens to their new expanded locations.
+///
+/// \param ArgIdDefLoc the location of the macro argument id inside the macro
+/// definition.
+/// \param Tokens the macro argument tokens to update.
+void TokenLexer::updateLocForMacroArgTokens(SourceLocation ArgIdSpellLoc,
+                                            Token *begin_tokens,
+                                            Token *end_tokens) {
+  SourceManager &SM = PP.getSourceManager();
+
+  SourceLocation InstLoc =
+      getExpansionLocForMacroDefLoc(ArgIdSpellLoc);
+  
+  while (begin_tokens < end_tokens) {
+    // If there's only one token just create a SLocEntry for it.
+    if (end_tokens - begin_tokens == 1) {
+      Token &Tok = *begin_tokens;
+      Tok.setLocation(SM.createMacroArgExpansionLoc(Tok.getLocation(),
+                                                    InstLoc,
+                                                    Tok.getLength()));
+      return;
+    }
+
+    updateConsecutiveMacroArgTokens(SM, InstLoc, begin_tokens, end_tokens);
+  }
 }