vendor/clang/clang-trunk-r290819

15 files changed, 3050 insertions, 2290 deletions

diff --git a/lib/Serialization/ASTCommon.cpp b/lib/Serialization/ASTCommon.cpp
index 22ead2b57c72..ecd249cc5025 100644
--- a/lib/Serialization/ASTCommon.cpp
+++ b/lib/Serialization/ASTCommon.cpp
@@ -183,6 +183,7 @@ serialization::getDefinitiveDeclContext(const DeclContext *DC) {
   case Decl::ExternCContext:
   case Decl::Namespace:
   case Decl::LinkageSpec:
+  case Decl::Export:
     return nullptr;
 
   // C/C++ tag types can only be defined in one place.
@@ -284,6 +285,7 @@ bool serialization::isRedeclarableDeclKind(unsigned Kind) {
   case Decl::NonTypeTemplateParm:
   case Decl::TemplateTemplateParm:
   case Decl::Using:
+  case Decl::UsingPack:
   case Decl::ObjCMethod:
   case Decl::ObjCCategory:
   case Decl::ObjCCategoryImpl:
@@ -291,6 +293,7 @@ bool serialization::isRedeclarableDeclKind(unsigned Kind) {
   case Decl::ObjCProperty:
   case Decl::ObjCCompatibleAlias:
   case Decl::LinkageSpec:
+  case Decl::Export:
   case Decl::ObjCPropertyImpl:
   case Decl::PragmaComment:
   case Decl::PragmaDetectMismatch:
@@ -307,6 +310,8 @@ bool serialization::isRedeclarableDeclKind(unsigned Kind) {
   case Decl::OMPCapturedExpr:
   case Decl::OMPDeclareReduction:
   case Decl::BuiltinTemplate:
+  case Decl::Decomposition:
+  case Decl::Binding:
     return false;
 
   // These indirectly derive from Redeclarable<T> but are not actually
diff --git a/lib/Serialization/ASTCommon.h b/lib/Serialization/ASTCommon.h
index 641165e4178f..cbc5f04738b1 100644
--- a/lib/Serialization/ASTCommon.h
+++ b/lib/Serialization/ASTCommon.h
@@ -30,6 +30,7 @@ enum DeclUpdateKind {
   UPD_CXX_INSTANTIATED_STATIC_DATA_MEMBER,
   UPD_CXX_INSTANTIATED_CLASS_DEFINITION,
   UPD_CXX_INSTANTIATED_DEFAULT_ARGUMENT,
+  UPD_CXX_INSTANTIATED_DEFAULT_MEMBER_INITIALIZER,
   UPD_CXX_RESOLVED_DTOR_DELETE,
   UPD_CXX_RESOLVED_EXCEPTION_SPEC,
   UPD_CXX_DEDUCED_RETURN_TYPE,
diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
index 9d1554a826aa..fe2c53b77e1d 100644
--- a/lib/Serialization/ASTReader.cpp
+++ b/lib/Serialization/ASTReader.cpp
@@ -1,4 +1,4 @@
-//===-- ASTReader.cpp - AST File Reader ----------------------------------===//
+//===-- ASTReader.cpp - AST File Reader -----------------------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -16,39 +16,62 @@
 #include "ASTReaderInternals.h"
 #include "clang/AST/ASTConsumer.h"
 #include "clang/AST/ASTContext.h"
+#include "clang/AST/ASTMutationListener.h"
+#include "clang/AST/ASTUnresolvedSet.h"
+#include "clang/AST/Decl.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/DeclGroup.h"
+#include "clang/AST/DeclObjC.h"
 #include "clang/AST/DeclTemplate.h"
 #include "clang/AST/Expr.h"
 #include "clang/AST/ExprCXX.h"
-#include "clang/Frontend/PCHContainerOperations.h"
-#include "clang/AST/ASTMutationListener.h"
 #include "clang/AST/NestedNameSpecifier.h"
+#include "clang/AST/RawCommentList.h"
 #include "clang/AST/Type.h"
 #include "clang/AST/TypeLocVisitor.h"
+#include "clang/AST/UnresolvedSet.h"
+#include "clang/Basic/CommentOptions.h"
 #include "clang/Basic/DiagnosticOptions.h"
+#include "clang/Basic/ExceptionSpecificationType.h"
 #include "clang/Basic/FileManager.h"
+#include "clang/Basic/FileSystemOptions.h"
+#include "clang/Basic/LangOptions.h"
+#include "clang/Basic/ObjCRuntime.h"
+#include "clang/Basic/OperatorKinds.h"
+#include "clang/Basic/Sanitizers.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Basic/SourceManagerInternals.h"
+#include "clang/Basic/Specifiers.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Basic/TargetOptions.h"
+#include "clang/Basic/TokenKinds.h"
 #include "clang/Basic/Version.h"
 #include "clang/Basic/VersionTuple.h"
-#include "clang/Frontend/Utils.h"
+#include "clang/Frontend/PCHContainerOperations.h"
 #include "clang/Lex/HeaderSearch.h"
 #include "clang/Lex/HeaderSearchOptions.h"
 #include "clang/Lex/MacroInfo.h"
+#include "clang/Lex/ModuleMap.h"
 #include "clang/Lex/PreprocessingRecord.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Lex/PreprocessorOptions.h"
 #include "clang/Sema/Scope.h"
 #include "clang/Sema/Sema.h"
+#include "clang/Sema/Weak.h"
 #include "clang/Serialization/ASTDeserializationListener.h"
 #include "clang/Serialization/GlobalModuleIndex.h"
 #include "clang/Serialization/ModuleManager.h"
 #include "clang/Serialization/SerializationDiagnostic.h"
+#include "llvm/ADT/APFloat.h"
+#include "llvm/ADT/APInt.h"
+#include "llvm/ADT/APSInt.h"
 #include "llvm/ADT/Hashing.h"
+#include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/Triple.h"
 #include "llvm/Bitcode/BitstreamReader.h"
 #include "llvm/Support/Compression.h"
+#include "llvm/Support/Compiler.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/MemoryBuffer.h"
@@ -56,16 +79,27 @@
 #include "llvm/Support/SaveAndRestore.h"
 #include "llvm/Support/raw_ostream.h"
 #include <algorithm>
+#include <cassert>
+#include <cstdint>
 #include <cstdio>
+#include <cstring>
+#include <ctime>
 #include <iterator>
+#include <limits>
+#include <map>
+#include <memory>
+#include <new>
+#include <string>
 #include <system_error>
+#include <tuple>
+#include <utility>
+#include <vector>
 
 using namespace clang;
 using namespace clang::serialization;
 using namespace clang::serialization::reader;
 using llvm::BitstreamCursor;
 
-
 //===----------------------------------------------------------------------===//
 // ChainedASTReaderListener implementation
 //===----------------------------------------------------------------------===//
@@ -75,14 +109,17 @@ ChainedASTReaderListener::ReadFullVersionInformation(StringRef FullVersion) {
   return First->ReadFullVersionInformation(FullVersion) ||
          Second->ReadFullVersionInformation(FullVersion);
 }
+
 void ChainedASTReaderListener::ReadModuleName(StringRef ModuleName) {
   First->ReadModuleName(ModuleName);
   Second->ReadModuleName(ModuleName);
 }
+
 void ChainedASTReaderListener::ReadModuleMapFile(StringRef ModuleMapPath) {
   First->ReadModuleMapFile(ModuleMapPath);
   Second->ReadModuleMapFile(ModuleMapPath);
 }
+
 bool
 ChainedASTReaderListener::ReadLanguageOptions(const LangOptions &LangOpts,
                                               bool Complain,
@@ -92,6 +129,7 @@ ChainedASTReaderListener::ReadLanguageOptions(const LangOptions &LangOpts,
          Second->ReadLanguageOptions(LangOpts, Complain,
                                      AllowCompatibleDifferences);
 }
+
 bool ChainedASTReaderListener::ReadTargetOptions(
     const TargetOptions &TargetOpts, bool Complain,
     bool AllowCompatibleDifferences) {
@@ -100,11 +138,13 @@ bool ChainedASTReaderListener::ReadTargetOptions(
          Second->ReadTargetOptions(TargetOpts, Complain,
                                    AllowCompatibleDifferences);
 }
+
 bool ChainedASTReaderListener::ReadDiagnosticOptions(
     IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts, bool Complain) {
   return First->ReadDiagnosticOptions(DiagOpts, Complain) ||
          Second->ReadDiagnosticOptions(DiagOpts, Complain);
 }
+
 bool
 ChainedASTReaderListener::ReadFileSystemOptions(const FileSystemOptions &FSOpts,
                                                 bool Complain) {
@@ -120,6 +160,7 @@ bool ChainedASTReaderListener::ReadHeaderSearchOptions(
          Second->ReadHeaderSearchOptions(HSOpts, SpecificModuleCachePath,
                                          Complain);
 }
+
 bool ChainedASTReaderListener::ReadPreprocessorOptions(
     const PreprocessorOptions &PPOpts, bool Complain,
     std::string &SuggestedPredefines) {
@@ -145,6 +186,7 @@ void ChainedASTReaderListener::visitModuleFile(StringRef Filename,
   First->visitModuleFile(Filename, Kind);
   Second->visitModuleFile(Filename, Kind);
 }
+
 bool ChainedASTReaderListener::visitInputFile(StringRef Filename,
                                               bool isSystem,
                                               bool isOverridden,
@@ -336,11 +378,13 @@ bool PCHValidator::ReadTargetOptions(const TargetOptions &TargetOpts,
 }
 
 namespace {
+
   typedef llvm::StringMap<std::pair<StringRef, bool /*IsUndef*/> >
     MacroDefinitionsMap;
   typedef llvm::DenseMap<DeclarationName, SmallVector<NamedDecl *, 8> >
     DeclsMap;
-}
+
+} // end anonymous namespace
 
 static bool checkDiagnosticGroupMappings(DiagnosticsEngine &StoredDiags,
                                          DiagnosticsEngine &Diags,
@@ -496,12 +540,16 @@ collectMacroDefinitions(const PreprocessorOptions &PPOpts,
 /// against the preprocessor options in an existing preprocessor.
 ///
 /// \param Diags If non-null, produce diagnostics for any mismatches incurred.
+/// \param Validate If true, validate preprocessor options. If false, allow
+///        macros defined by \p ExistingPPOpts to override those defined by
+///        \p PPOpts in SuggestedPredefines.
 static bool checkPreprocessorOptions(const PreprocessorOptions &PPOpts,
                                      const PreprocessorOptions &ExistingPPOpts,
                                      DiagnosticsEngine *Diags,
                                      FileManager &FileMgr,
                                      std::string &SuggestedPredefines,
-                                     const LangOptions &LangOpts) {
+                                     const LangOptions &LangOpts,
+                                     bool Validate = true) {
   // Check macro definitions.
   MacroDefinitionsMap ASTFileMacros;
   collectMacroDefinitions(PPOpts, ASTFileMacros);
@@ -517,7 +565,7 @@ static bool checkPreprocessorOptions(const PreprocessorOptions &PPOpts,
     // Check whether we know anything about this macro name or not.
     llvm::StringMap<std::pair<StringRef, bool /*IsUndef*/> >::iterator Known
       = ASTFileMacros.find(MacroName);
-    if (Known == ASTFileMacros.end()) {
+    if (!Validate || Known == ASTFileMacros.end()) {
       // FIXME: Check whether this identifier was referenced anywhere in the
       // AST file. If so, we should reject the AST file. Unfortunately, this
       // information isn't in the control block. What shall we do about it?
@@ -560,7 +608,7 @@ static bool checkPreprocessorOptions(const PreprocessorOptions &PPOpts,
   }
 
   // Check whether we're using predefines.
-  if (PPOpts.UsePredefines != ExistingPPOpts.UsePredefines) {
+  if (PPOpts.UsePredefines != ExistingPPOpts.UsePredefines && Validate) {
     if (Diags) {
       Diags->Report(diag::err_pch_undef) << ExistingPPOpts.UsePredefines;
     }
@@ -569,7 +617,7 @@ static bool checkPreprocessorOptions(const PreprocessorOptions &PPOpts,
 
   // Detailed record is important since it is used for the module cache hash.
   if (LangOpts.Modules &&
-      PPOpts.DetailedRecord != ExistingPPOpts.DetailedRecord) {
+      PPOpts.DetailedRecord != ExistingPPOpts.DetailedRecord && Validate) {
     if (Diags) {
       Diags->Report(diag::err_pch_pp_detailed_record) << PPOpts.DetailedRecord;
     }
@@ -618,6 +666,19 @@ bool PCHValidator::ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
                                   PP.getLangOpts());
 }
 
+bool SimpleASTReaderListener::ReadPreprocessorOptions(
+                                  const PreprocessorOptions &PPOpts,
+                                  bool Complain,
+                                  std::string &SuggestedPredefines) {
+  return checkPreprocessorOptions(PPOpts,
+                                  PP.getPreprocessorOpts(),
+                                  nullptr,
+                                  PP.getFileManager(),
+                                  SuggestedPredefines,
+                                  PP.getLangOpts(),
+                                  false);
+}
+
 /// Check the header search options deserialized from the control block
 /// against the header search options in an existing preprocessor.
 ///
@@ -662,13 +723,10 @@ void ASTReader::setDeserializationListener(ASTDeserializationListener *Listener,
   OwnsDeserializationListener = TakeOwnership;
 }
 
-
-
 unsigned ASTSelectorLookupTrait::ComputeHash(Selector Sel) {
   return serialization::ComputeHash(Sel);
 }
 
-
 std::pair<unsigned, unsigned>
 ASTSelectorLookupTrait::ReadKeyDataLength(const unsigned char*& d) {
   using namespace llvm::support;
@@ -677,7 +735,7 @@ ASTSelectorLookupTrait::ReadKeyDataLength(const unsigned char*& d) {
   return std::make_pair(KeyLen, DataLen);
 }
 
-ASTSelectorLookupTrait::internal_key_type 
+ASTSelectorLookupTrait::internal_key_type
 ASTSelectorLookupTrait::ReadKey(const unsigned char* d, unsigned) {
   using namespace llvm::support;
   SelectorTable &SelTable = Reader.getContext().Selectors;
@@ -698,8 +756,8 @@ ASTSelectorLookupTrait::ReadKey(const unsigned char* d, unsigned) {
   return SelTable.getSelector(N, Args.data());
 }
 
-ASTSelectorLookupTrait::data_type 
-ASTSelectorLookupTrait::ReadData(Selector, const unsigned char* d, 
+ASTSelectorLookupTrait::data_type
+ASTSelectorLookupTrait::ReadData(Selector, const unsigned char* d,
                                  unsigned DataLen) {
   using namespace llvm::support;
 
@@ -1138,7 +1196,7 @@ bool ASTReader::ReadSourceManagerBlock(ModuleFile &F) {
   RecordData Record;
   while (true) {
     llvm::BitstreamEntry E = SLocEntryCursor.advanceSkippingSubblocks();
-    
+
     switch (E.Kind) {
     case llvm::BitstreamEntry::SubBlock: // Handled for us already.
     case llvm::BitstreamEntry::Error:
@@ -1150,7 +1208,7 @@ bool ASTReader::ReadSourceManagerBlock(ModuleFile &F) {
       // The interesting case.
       break;
     }
-    
+
     // Read a record.
     Record.clear();
     StringRef Blob;
@@ -1246,7 +1304,7 @@ bool ASTReader::ReadSLocEntry(int ID) {
     Error("incorrectly-formatted source location entry in AST file");
     return true;
   }
-  
+
   RecordData Record;
   StringRef Blob;
   switch (SLocEntryCursor.readRecord(Entry.ID, Record, &Blob)) {
@@ -1312,8 +1370,7 @@ bool ASTReader::ReadSLocEntry(int ID) {
     SrcMgr::CharacteristicKind
       FileCharacter = (SrcMgr::CharacteristicKind)Record[2];
     SourceLocation IncludeLoc = ReadSourceLocation(*F, Record[1]);
-    if (IncludeLoc.isInvalid() &&
-        (F->Kind == MK_ImplicitModule || F->Kind == MK_ExplicitModule)) {
+    if (IncludeLoc.isInvalid() && F->isModule()) {
       IncludeLoc = getImportLocation(F);
     }
 
@@ -1351,7 +1408,7 @@ std::pair<SourceLocation, StringRef> ASTReader::getModuleImportLoc(int ID) {
 
   // Find which module file this entry lands in.
   ModuleFile *M = GlobalSLocEntryMap.find(-ID)->second;
-  if (M->Kind != MK_ImplicitModule && M->Kind != MK_ExplicitModule)
+  if (!M->isModule())
     return std::make_pair(SourceLocation(), "");
 
   // FIXME: Can we map this down to a particular submodule? That would be
@@ -1363,7 +1420,7 @@ std::pair<SourceLocation, StringRef> ASTReader::getModuleImportLoc(int ID) {
 SourceLocation ASTReader::getImportLocation(ModuleFile *F) {
   if (F->ImportLoc.isValid())
     return F->ImportLoc;
-  
+
   // Otherwise we have a PCH. It's considered to be "imported" at the first
   // location of its includer.
   if (F->ImportedBy.empty() || !F->ImportedBy[0]) {
@@ -1425,7 +1482,7 @@ MacroInfo *ASTReader::ReadMacroRecord(ModuleFile &F, uint64_t Offset) {
     // be able to reseek within the block and read entries.
     unsigned Flags = BitstreamCursor::AF_DontPopBlockAtEnd;
     llvm::BitstreamEntry Entry = Stream.advanceSkippingSubblocks(Flags);
-    
+
     switch (Entry.Kind) {
     case llvm::BitstreamEntry::SubBlock: // Handled for us already.
     case llvm::BitstreamEntry::Error:
@@ -1517,13 +1574,13 @@ MacroInfo *ASTReader::ReadMacroRecord(ModuleFile &F, uint64_t Offset) {
   }
 }
 
-PreprocessedEntityID 
+PreprocessedEntityID
 ASTReader::getGlobalPreprocessedEntityID(ModuleFile &M, unsigned LocalID) const {
-  ContinuousRangeMap<uint32_t, int, 2>::const_iterator 
+  ContinuousRangeMap<uint32_t, int, 2>::const_iterator
     I = M.PreprocessedEntityRemap.find(LocalID - NUM_PREDEF_PP_ENTITY_IDS);
-  assert(I != M.PreprocessedEntityRemap.end() 
+  assert(I != M.PreprocessedEntityRemap.end()
          && "Invalid index into preprocessed entity index remap");
-  
+
   return LocalID + I->second;
 }
 
@@ -1531,22 +1588,21 @@ unsigned HeaderFileInfoTrait::ComputeHash(internal_key_ref ikey) {
   return llvm::hash_combine(ikey.Size, ikey.ModTime);
 }
 
-HeaderFileInfoTrait::internal_key_type 
+HeaderFileInfoTrait::internal_key_type
 HeaderFileInfoTrait::GetInternalKey(const FileEntry *FE) {
   internal_key_type ikey = {FE->getSize(),
                             M.HasTimestamps ? FE->getModificationTime() : 0,
                             FE->getName(), /*Imported*/ false};
   return ikey;
 }
-    
+
 bool HeaderFileInfoTrait::EqualKey(internal_key_ref a, internal_key_ref b) {
   if (a.Size != b.Size || (a.ModTime && b.ModTime && a.ModTime != b.ModTime))
     return false;
 
-  if (llvm::sys::path::is_absolute(a.Filename) &&
-      strcmp(a.Filename, b.Filename) == 0)
+  if (llvm::sys::path::is_absolute(a.Filename) && a.Filename == b.Filename)
     return true;
-  
+
   // Determine whether the actual files are equivalent.
   FileManager &FileMgr = Reader.getFileManager();
   auto GetFile = [&](const internal_key_type &Key) -> const FileEntry* {
@@ -1562,7 +1618,7 @@ bool HeaderFileInfoTrait::EqualKey(internal_key_ref a, internal_key_ref b) {
   const FileEntry *FEB = GetFile(b);
   return FEA && FEA == FEB;
 }
-    
+
 std::pair<unsigned, unsigned>
 HeaderFileInfoTrait::ReadKeyDataLength(const unsigned char*& d) {
   using namespace llvm::support;
@@ -1582,7 +1638,7 @@ HeaderFileInfoTrait::ReadKey(const unsigned char *d, unsigned) {
   return ikey;
 }
 
-HeaderFileInfoTrait::data_type 
+HeaderFileInfoTrait::data_type
 HeaderFileInfoTrait::ReadData(internal_key_ref key, const unsigned char *d,
                               unsigned DataLen) {
   const unsigned char *End = d + DataLen;
@@ -1602,7 +1658,7 @@ HeaderFileInfoTrait::ReadData(internal_key_ref key, const unsigned char *d,
       M, endian::readNext<uint32_t, little, unaligned>(d));
   if (unsigned FrameworkOffset =
           endian::readNext<uint32_t, little, unaligned>(d)) {
-    // The framework offset is 1 greater than the actual offset, 
+    // The framework offset is 1 greater than the actual offset,
     // since 0 is used as an indicator for "no framework name".
     StringRef FrameworkName(FrameworkStrings + FrameworkOffset - 1);
     HFI.Framework = HS->getUniqueFrameworkName(FrameworkName);
@@ -1655,7 +1711,7 @@ void ASTReader::ReadDefinedMacros() {
     BitstreamCursor &MacroCursor = I->MacroCursor;
 
     // If there was no preprocessor block, skip this file.
-    if (!MacroCursor.getBitStreamReader())
+    if (MacroCursor.getBitcodeBytes().empty())
       continue;
 
     BitstreamCursor Cursor = MacroCursor;
@@ -1664,7 +1720,7 @@ void ASTReader::ReadDefinedMacros() {
     RecordData Record;
     while (true) {
       llvm::BitstreamEntry E = Cursor.advanceSkippingSubblocks();
-      
+
       switch (E.Kind) {
       case llvm::BitstreamEntry::SubBlock: // Handled for us already.
       case llvm::BitstreamEntry::Error:
@@ -1672,13 +1728,13 @@ void ASTReader::ReadDefinedMacros() {
         return;
       case llvm::BitstreamEntry::EndBlock:
         goto NextCursor;
-        
+
       case llvm::BitstreamEntry::Record:
         Record.clear();
         switch (Cursor.readRecord(E.ID, Record)) {
         default:  // Default behavior: ignore.
           break;
-          
+
         case PP_MACRO_OBJECT_LIKE:
         case PP_MACRO_FUNCTION_LIKE: {
           IdentifierInfo *II = getLocalIdentifier(*I, Record[0]);
@@ -1686,7 +1742,7 @@ void ASTReader::ReadDefinedMacros() {
             updateOutOfDateIdentifier(*II);
           break;
         }
-          
+
         case PP_TOKEN:
           // Ignore tokens.
           break;
@@ -1699,6 +1755,7 @@ void ASTReader::ReadDefinedMacros() {
 }
 
 namespace {
+
   /// \brief Visitor class used to look up identifirs in an AST file.
   class IdentifierLookupVisitor {
     StringRef Name;
@@ -1737,7 +1794,7 @@ namespace {
           IdTable->find_hashed(Name, NameHash, &Trait);
       if (Pos == IdTable->end())
         return false;
-      
+
       // Dereferencing the iterator has the effect of building the
       // IdentifierInfo node and populating it with the various
       // declarations it needs.
@@ -1745,12 +1802,13 @@ namespace {
       Found = *Pos;
       return true;
     }
-    
+
     // \brief Retrieve the identifier info found within the module
     // files.
     IdentifierInfo *getIdentifierInfo() const { return Found; }
   };
-}
+
+} // end anonymous namespace
 
 void ASTReader::updateOutOfDateIdentifier(IdentifierInfo &II) {
   // Note that we are loading an identifier.
@@ -1780,7 +1838,7 @@ void ASTReader::updateOutOfDateIdentifier(IdentifierInfo &II) {
 void ASTReader::markIdentifierUpToDate(IdentifierInfo *II) {
   if (!II)
     return;
-  
+
   II->setOutOfDate(false);
 
   // Update the generation for this identifier.
@@ -1861,7 +1919,7 @@ void ASTReader::resolvePendingMacro(IdentifierInfo *II,
 
   // Don't read the directive history for a module; we don't have anywhere
   // to put it.
-  if (M.Kind == MK_ImplicitModule || M.Kind == MK_ExplicitModule)
+  if (M.isModule())
     return;
 
   // Deserialize the macro directives history in reverse source-order.
@@ -1895,7 +1953,7 @@ void ASTReader::resolvePendingMacro(IdentifierInfo *II,
   }
 
   if (Latest)
-    PP.setLoadedMacroDirective(II, Latest);
+    PP.setLoadedMacroDirective(II, Earliest, Latest);
 }
 
 ASTReader::InputFileInfo
@@ -1925,6 +1983,7 @@ ASTReader::readInputFileInfo(ModuleFile &F, unsigned ID) {
   return R;
 }
 
+static unsigned moduleKindForDiagnostic(ModuleKind Kind);
 InputFile ASTReader::getInputFile(ModuleFile &F, unsigned ID, bool Complain) {
   // If this ID is bogus, just return an empty input file.
   if (ID == 0 || ID > F.InputFilesLoaded.size())
@@ -1941,7 +2000,7 @@ InputFile ASTReader::getInputFile(ModuleFile &F, unsigned ID, bool Complain) {
   BitstreamCursor &Cursor = F.InputFilesCursor;
   SavedStreamPosition SavedPosition(Cursor);
   Cursor.JumpToBit(F.InputFileOffsets[ID-1]);
-  
+
   InputFileInfo FI = readInputFileInfo(F, ID);
   off_t StoredSize = FI.StoredSize;
   time_t StoredTime = FI.StoredTime;
@@ -1974,7 +2033,7 @@ InputFile ASTReader::getInputFile(ModuleFile &F, unsigned ID, bool Complain) {
       ErrorStr += "' referenced by AST file '";
       ErrorStr += F.FileName;
       ErrorStr += "'";
-      Error(ErrorStr.c_str());
+      Error(ErrorStr);
     }
     // Record that we didn't find the file.
     F.InputFilesLoaded[ID-1] = InputFile::getNotFound();
@@ -2021,7 +2080,13 @@ InputFile ASTReader::getInputFile(ModuleFile &F, unsigned ID, bool Complain) {
 
       // The top-level PCH is stale.
       StringRef TopLevelPCHName(ImportStack.back()->FileName);
-      Error(diag::err_fe_pch_file_modified, Filename, TopLevelPCHName);
+      unsigned DiagnosticKind = moduleKindForDiagnostic(ImportStack.back()->Kind);
+      if (DiagnosticKind == 0)
+        Error(diag::err_fe_pch_file_modified, Filename, TopLevelPCHName);
+      else if (DiagnosticKind == 1)
+        Error(diag::err_fe_module_file_modified, Filename, TopLevelPCHName);
+      else
+        Error(diag::err_fe_ast_file_modified, Filename, TopLevelPCHName);
 
       // Print the import stack.
       if (ImportStack.size() > 1 && !Diags.isDiagnosticInFlight()) {
@@ -2084,16 +2149,16 @@ static bool isDiagnosedResult(ASTReader::ASTReadResult ARR, unsigned Caps) {
 ASTReader::ASTReadResult ASTReader::ReadOptionsBlock(
     BitstreamCursor &Stream, unsigned ClientLoadCapabilities,
     bool AllowCompatibleConfigurationMismatch, ASTReaderListener &Listener,
-    std::string &SuggestedPredefines) {
+    std::string &SuggestedPredefines, bool ValidateDiagnosticOptions) {
   if (Stream.EnterSubBlock(OPTIONS_BLOCK_ID))
     return Failure;
 
   // Read all of the records in the options block.
   RecordData Record;
   ASTReadResult Result = Success;
-  while (1) {
+  while (true) {
     llvm::BitstreamEntry Entry = Stream.advance();
-    
+
     switch (Entry.Kind) {
     case llvm::BitstreamEntry::Error:
     case llvm::BitstreamEntry::SubBlock:
@@ -2128,7 +2193,8 @@ ASTReader::ASTReadResult ASTReader::ReadOptionsBlock(
 
     case DIAGNOSTIC_OPTIONS: {
       bool Complain = (ClientLoadCapabilities & ARR_OutOfDate) == 0;
-      if (!AllowCompatibleConfigurationMismatch &&
+      if (ValidateDiagnosticOptions &&
+          !AllowCompatibleConfigurationMismatch &&
           ParseDiagnosticOptions(Record, Complain, Listener))
         return OutOfDate;
       break;
@@ -2178,9 +2244,9 @@ ASTReader::ReadControlBlock(ModuleFile &F,
   RecordData Record;
   unsigned NumInputs = 0;
   unsigned NumUserInputs = 0;
-  while (1) {
+  while (true) {
     llvm::BitstreamEntry Entry = Stream.advance();
-    
+
     switch (Entry.Kind) {
     case llvm::BitstreamEntry::Error:
       Error("malformed block record in AST file");
@@ -2193,7 +2259,8 @@ ASTReader::ReadControlBlock(ModuleFile &F,
       // All user input files reside at the index range [0, NumUserInputs), and
       // system input files reside at [NumUserInputs, NumInputs). For explicitly
       // loaded module files, ignore missing inputs.
-      if (!DisableValidation && F.Kind != MK_ExplicitModule) {
+      if (!DisableValidation && F.Kind != MK_ExplicitModule &&
+          F.Kind != MK_PrebuiltModule) {
         bool Complain = (ClientLoadCapabilities & ARR_OutOfDate) == 0;
 
         // If we are reading a module, we will create a verification timestamp,
@@ -2224,7 +2291,8 @@ ASTReader::ReadControlBlock(ModuleFile &F,
           bool IsSystem = I >= NumUserInputs;
           InputFileInfo FI = readInputFileInfo(F, I+1);
           Listener->visitInputFile(FI.Filename, IsSystem, FI.Overridden,
-                                   F.Kind == MK_ExplicitModule);
+                                   F.Kind == MK_ExplicitModule ||
+                                   F.Kind == MK_PrebuiltModule);
         }
       }
 
@@ -2254,11 +2322,14 @@ ASTReader::ReadControlBlock(ModuleFile &F,
           //
           // FIXME: Allow this for files explicitly specified with -include-pch.
           bool AllowCompatibleConfigurationMismatch =
-              F.Kind == MK_ExplicitModule;
+              F.Kind == MK_ExplicitModule || F.Kind == MK_PrebuiltModule;
+          const HeaderSearchOptions &HSOpts =
+              PP.getHeaderSearchInfo().getHeaderSearchOpts();
 
           Result = ReadOptionsBlock(Stream, ClientLoadCapabilities,
                                     AllowCompatibleConfigurationMismatch,
-                                    *Listener, SuggestedPredefines);
+                                    *Listener, SuggestedPredefines,
+                                    HSOpts.ModulesValidateDiagnosticOptions);
           if (Result == Failure) {
             Error("malformed block record in AST file");
             return Result;
@@ -2278,7 +2349,7 @@ ASTReader::ReadControlBlock(ModuleFile &F,
           return Failure;
         }
         continue;
-          
+
       default:
         if (Stream.SkipBlock()) {
           Error("malformed block record in AST file");
@@ -2286,7 +2357,7 @@ ASTReader::ReadControlBlock(ModuleFile &F,
         }
         continue;
       }
-      
+
     case llvm::BitstreamEntry::Record:
       // The interesting case.
       break;
@@ -2338,7 +2409,7 @@ ASTReader::ReadControlBlock(ModuleFile &F,
       break;
 
     case IMPORTS: {
-      // Load each of the imported PCH files. 
+      // Load each of the imported PCH files.
       unsigned Idx = 0, N = Record.size();
       while (Idx < N) {
         // Read information about the AST file.
@@ -2413,7 +2484,7 @@ ASTReader::ReadControlBlock(ModuleFile &F,
       if (M && M->Directory) {
         // If we're implicitly loading a module, the base directory can't
         // change between the build and use.
-        if (F.Kind != MK_ExplicitModule) {
+        if (F.Kind != MK_ExplicitModule && F.Kind != MK_PrebuiltModule) {
           const DirectoryEntry *BuildDir =
               PP.getFileManager().getDirectory(Blob);
           if (!BuildDir || BuildDir != M->Directory) {
@@ -2458,9 +2529,9 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
 
   // Read all of the records and blocks for the AST file.
   RecordData Record;
-  while (1) {
+  while (true) {
     llvm::BitstreamEntry Entry = Stream.advance();
-    
+
     switch (Entry.Kind) {
     case llvm::BitstreamEntry::Error:
       Error("error at end of module block in AST file");
@@ -2475,7 +2546,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       if (DC->hasExternalLexicalStorage() &&
           !getContext().getLangOpts().CPlusPlus)
         DC->setMustBuildLookupTable();
-      
+
       return Success;
     }
     case llvm::BitstreamEntry::SubBlock:
@@ -2498,7 +2569,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         F.MacroCursor = Stream;
         if (!PP.getExternalSource())
           PP.setExternalSource(this);
-        
+
         if (Stream.SkipBlock() ||
             ReadBlockAbbrevs(F.MacroCursor, PREPROCESSOR_BLOCK_ID)) {
           Error("malformed block record in AST file");
@@ -2506,7 +2577,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         }
         F.MacroStartOffset = F.MacroCursor.GetCurrentBitNo();
         break;
-        
+
       case PREPROCESSOR_DETAIL_BLOCK_ID:
         F.PreprocessorDetailCursor = Stream;
         if (Stream.SkipBlock() ||
@@ -2517,23 +2588,23 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
             }
         F.PreprocessorDetailStartOffset
         = F.PreprocessorDetailCursor.GetCurrentBitNo();
-        
+
         if (!PP.getPreprocessingRecord())
           PP.createPreprocessingRecord();
         if (!PP.getPreprocessingRecord()->getExternalSource())
           PP.getPreprocessingRecord()->SetExternalSource(*this);
         break;
-        
+
       case SOURCE_MANAGER_BLOCK_ID:
         if (ReadSourceManagerBlock(F))
           return Failure;
         break;
-        
+
       case SUBMODULE_BLOCK_ID:
         if (ASTReadResult Result = ReadSubmoduleBlock(F, ClientLoadCapabilities))
           return Result;
         break;
-        
+
       case COMMENTS_BLOCK_ID: {
         BitstreamCursor C = Stream;
         if (Stream.SkipBlock() ||
@@ -2544,7 +2615,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         CommentsCursors.push_back(std::make_pair(C, &F));
         break;
       }
-        
+
       default:
         if (Stream.SkipBlock()) {
           Error("malformed block record in AST file");
@@ -2553,7 +2624,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         break;
       }
       continue;
-    
+
     case llvm::BitstreamEntry::Record:
       // The interesting case.
       break;
@@ -2575,21 +2646,21 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       F.LocalNumTypes = Record[0];
       unsigned LocalBaseTypeIndex = Record[1];
       F.BaseTypeIndex = getTotalNumTypes();
-        
+
       if (F.LocalNumTypes > 0) {
         // Introduce the global -> local mapping for types within this module.
         GlobalTypeMap.insert(std::make_pair(getTotalNumTypes(), &F));
-        
+
         // Introduce the local -> global mapping for types within this module.
         F.TypeRemap.insertOrReplace(
-          std::make_pair(LocalBaseTypeIndex, 
+          std::make_pair(LocalBaseTypeIndex,
                          F.BaseTypeIndex - LocalBaseTypeIndex));
 
         TypesLoaded.resize(TypesLoaded.size() + F.LocalNumTypes);
       }
       break;
     }
-        
+
     case DECL_OFFSET: {
       if (F.LocalNumDecls != 0) {
         Error("duplicate DECL_OFFSET record in AST file");
@@ -2599,18 +2670,18 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       F.LocalNumDecls = Record[0];
       unsigned LocalBaseDeclID = Record[1];
       F.BaseDeclID = getTotalNumDecls();
-        
+
       if (F.LocalNumDecls > 0) {
-        // Introduce the global -> local mapping for declarations within this 
+        // Introduce the global -> local mapping for declarations within this
         // module.
         GlobalDeclMap.insert(
           std::make_pair(getTotalNumDecls() + NUM_PREDEF_DECL_IDS, &F));
-        
+
         // Introduce the local -> global mapping for declarations within this
         // module.
         F.DeclRemap.insertOrReplace(
           std::make_pair(LocalBaseDeclID, F.BaseDeclID - LocalBaseDeclID));
-        
+
         // Introduce the global -> local mapping for declarations within this
         // module.
         F.GlobalToLocalDeclIDs[&F] = LocalBaseDeclID;
@@ -2619,7 +2690,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       }
       break;
     }
-        
+
     case TU_UPDATE_LEXICAL: {
       DeclContext *TU = Context.getTranslationUnitDecl();
       LexicalContents Contents(
@@ -2651,7 +2722,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
             (const unsigned char *)F.IdentifierTableData + sizeof(uint32_t),
             (const unsigned char *)F.IdentifierTableData,
             ASTIdentifierLookupTrait(*this, F));
-        
+
         PP.getIdentifierTable().setExternalIdentifierLookup(this);
       }
       break;
@@ -2665,13 +2736,13 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       F.LocalNumIdentifiers = Record[0];
       unsigned LocalBaseIdentifierID = Record[1];
       F.BaseIdentifierID = getTotalNumIdentifiers();
-        
+
       if (F.LocalNumIdentifiers > 0) {
         // Introduce the global -> local mapping for identifiers within this
         // module.
-        GlobalIdentifierMap.insert(std::make_pair(getTotalNumIdentifiers() + 1, 
+        GlobalIdentifierMap.insert(std::make_pair(getTotalNumIdentifiers() + 1,
                                                   &F));
-        
+
         // Introduce the local -> global mapping for identifiers within this
         // module.
         F.IdentifierRemap.insertOrReplace(
@@ -2738,11 +2809,11 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         Error("invalid weak identifiers record");
         return Failure;
       }
-        
-      // FIXME: Ignore weak undeclared identifiers from non-original PCH 
+
+      // FIXME: Ignore weak undeclared identifiers from non-original PCH
       // files. This isn't the way to do it :)
       WeakUndeclaredIdentifiers.clear();
-        
+
       // Translate the weak, undeclared identifiers into global IDs.
       for (unsigned I = 0, N = Record.size(); I < N; /* in loop */) {
         WeakUndeclaredIdentifiers.push_back(
@@ -2760,13 +2831,13 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       F.LocalNumSelectors = Record[0];
       unsigned LocalBaseSelectorID = Record[1];
       F.BaseSelectorID = getTotalNumSelectors();
-        
+
       if (F.LocalNumSelectors > 0) {
-        // Introduce the global -> local mapping for selectors within this 
+        // Introduce the global -> local mapping for selectors within this
         // module.
         GlobalSelectorMap.insert(std::make_pair(getTotalNumSelectors()+1, &F));
-        
-        // Introduce the local -> global mapping for selectors within this 
+
+        // Introduce the local -> global mapping for selectors within this
         // module.
         F.SelectorRemap.insertOrReplace(
           std::make_pair(LocalBaseSelectorID,
@@ -2776,7 +2847,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       }
       break;
     }
-        
+
     case METHOD_POOL:
       F.SelectorLookupTableData = (const unsigned char *)Blob.data();
       if (Record[0])
@@ -2791,7 +2862,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
     case REFERENCED_SELECTOR_POOL:
       if (!Record.empty()) {
         for (unsigned Idx = 0, N = Record.size() - 1; Idx < N; /* in loop */) {
-          ReferencedSelectorsData.push_back(getGlobalSelectorID(F, 
+          ReferencedSelectorsData.push_back(getGlobalSelectorID(F,
                                                                 Record[Idx++]));
           ReferencedSelectorsData.push_back(ReadSourceLocation(F, Record, Idx).
                                               getRawEncoding());
@@ -2803,7 +2874,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       if (!Record.empty() && Listener)
         Listener->ReadCounter(F, Record[0]);
       break;
-      
+
     case FILE_SORTED_DECLS:
       F.FileSortedDecls = (const DeclID *)Blob.data();
       F.NumFileSortedDecls = Record[0];
@@ -2840,7 +2911,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       // This module. Base was 2 when being compiled.
       F.SLocRemap.insertOrReplace(std::make_pair(2U,
                                   static_cast<int>(F.SLocEntryBaseOffset - 2)));
-      
+
       TotalNumSLocEntries += F.LocalNumSLocEntries;
       break;
     }
@@ -2932,7 +3003,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         Error("Multiple SOURCE_LOCATION_PRELOADS records in AST file");
         return Failure;
       }
-      
+
       F.PreloadSLocEntries.swap(Record);
       break;
     }
@@ -2947,12 +3018,12 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         Error("Invalid VTABLE_USES record");
         return Failure;
       }
-        
+
       // Later tables overwrite earlier ones.
       // FIXME: Modules will have some trouble with this. This is clearly not
       // the right way to do this.
       VTableUses.clear();
-        
+
       for (unsigned Idx = 0, N = Record.size(); Idx != N; /* In loop */) {
         VTableUses.push_back(getGlobalDeclID(F, Record[Idx++]));
         VTableUses.push_back(
@@ -2980,7 +3051,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       break;
 
     case SEMA_DECL_REFS:
-      if (Record.size() != 2) {
+      if (Record.size() != 3) {
         Error("Invalid SEMA_DECL_REFS block");
         return Failure;
       }
@@ -2994,13 +3065,13 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       F.NumPreprocessedEntities = Blob.size() / sizeof(PPEntityOffset);
 
       unsigned LocalBasePreprocessedEntityID = Record[0];
-      
+
       unsigned StartingID;
       if (!PP.getPreprocessingRecord())
         PP.createPreprocessingRecord();
       if (!PP.getPreprocessingRecord()->getExternalSource())
         PP.getPreprocessingRecord()->SetExternalSource(*this);
-      StartingID 
+      StartingID
         = PP.getPreprocessingRecord()
             ->allocateLoadedEntities(F.NumPreprocessedEntities);
       F.BasePreprocessedEntityID = StartingID;
@@ -3009,7 +3080,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         // Introduce the global -> local mapping for preprocessed entities in
         // this module.
         GlobalPreprocessedEntityMap.insert(std::make_pair(StartingID, &F));
-       
+
         // Introduce the local -> global mapping for preprocessed entities in
         // this module.
         F.PreprocessedEntityRemap.insertOrReplace(
@@ -3019,7 +3090,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
 
       break;
     }
-        
+
     case DECL_UPDATE_OFFSETS: {
       if (Record.size() % 2 != 0) {
         Error("invalid DECL_UPDATE_OFFSETS block in AST file");
@@ -3042,12 +3113,12 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         Error("duplicate OBJC_CATEGORIES_MAP record in AST file");
         return Failure;
       }
-      
+
       F.LocalNumObjCCategoriesInMap = Record[0];
       F.ObjCCategoriesMap = (const ObjCCategoriesInfo *)Blob.data();
       break;
     }
-        
+
     case OBJC_CATEGORIES:
       F.ObjCCategories.swap(Record);
       break;
@@ -3059,7 +3130,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         F.PragmaDiagMappings.insert(F.PragmaDiagMappings.end(),
                                     Record.begin(), Record.end());
       break;
-        
+
     case CUDA_SPECIAL_DECL_REFS:
       // Later tables overwrite earlier ones.
       // FIXME: Modules will have trouble with this.
@@ -3076,32 +3147,62 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
           = HeaderFileInfoLookupTable::Create(
                    (const unsigned char *)F.HeaderFileInfoTableData + Record[0],
                    (const unsigned char *)F.HeaderFileInfoTableData,
-                   HeaderFileInfoTrait(*this, F, 
+                   HeaderFileInfoTrait(*this, F,
                                        &PP.getHeaderSearchInfo(),
                                        Blob.data() + Record[2]));
-        
+
         PP.getHeaderSearchInfo().SetExternalSource(this);
         if (!PP.getHeaderSearchInfo().getExternalLookup())
           PP.getHeaderSearchInfo().SetExternalLookup(this);
       }
       break;
     }
-        
+
     case FP_PRAGMA_OPTIONS:
       // Later tables overwrite earlier ones.
       FPPragmaOptions.swap(Record);
       break;
 
     case OPENCL_EXTENSIONS:
-      // Later tables overwrite earlier ones.
-      OpenCLExtensions.swap(Record);
+      for (unsigned I = 0, E = Record.size(); I != E; ) {
+        auto Name = ReadString(Record, I);
+        auto &Opt = OpenCLExtensions.OptMap[Name];
+        Opt.Supported = Record[I++] != 0;
+        Opt.Enabled = Record[I++] != 0;
+        Opt.Avail = Record[I++];
+        Opt.Core = Record[I++];
+      }
+      break;
+
+    case OPENCL_EXTENSION_TYPES:
+      for (unsigned I = 0, E = Record.size(); I != E;) {
+        auto TypeID = static_cast<::TypeID>(Record[I++]);
+        auto *Type = GetType(TypeID).getTypePtr();
+        auto NumExt = static_cast<unsigned>(Record[I++]);
+        for (unsigned II = 0; II != NumExt; ++II) {
+          auto Ext = ReadString(Record, I);
+          OpenCLTypeExtMap[Type].insert(Ext);
+        }
+      }
+      break;
+
+    case OPENCL_EXTENSION_DECLS:
+      for (unsigned I = 0, E = Record.size(); I != E;) {
+        auto DeclID = static_cast<::DeclID>(Record[I++]);
+        auto *Decl = GetDecl(DeclID);
+        auto NumExt = static_cast<unsigned>(Record[I++]);
+        for (unsigned II = 0; II != NumExt; ++II) {
+          auto Ext = ReadString(Record, I);
+          OpenCLDeclExtMap[Decl].insert(Ext);
+        }
+      }
       break;
 
     case TENTATIVE_DEFINITIONS:
       for (unsigned I = 0, N = Record.size(); I != N; ++I)
         TentativeDefinitions.push_back(getGlobalDeclID(F, Record[I]));
       break;
-        
+
     case KNOWN_NAMESPACES:
       for (unsigned I = 0, N = Record.size(); I != N; ++I)
         KnownNamespaces.push_back(getGlobalDeclID(F, Record[I]));
@@ -3137,7 +3238,7 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       break;
 
     case IMPORTED_MODULES: {
-      if (F.Kind != MK_ImplicitModule && F.Kind != MK_ExplicitModule) {
+      if (!F.isModule()) {
         // If we aren't loading a module (which has its own exports), make
         // all of the imported modules visible.
         // FIXME: Deal with macros-only imports.
@@ -3210,6 +3311,14 @@ ASTReader::ReadASTBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         UnusedLocalTypedefNameCandidates.push_back(
             getGlobalDeclID(F, Record[I]));
       break;
+
+    case CUDA_PRAGMA_FORCE_HOST_DEVICE_DEPTH:
+      if (Record.size() != 1) {
+        Error("invalid cuda pragma options record");
+        return Failure;
+      }
+      ForceCUDAHostDeviceDepth = Record[0];
+      break;
     }
   }
 }
@@ -3221,7 +3330,7 @@ ASTReader::ReadModuleMapFileBlock(RecordData &Record, ModuleFile &F,
   unsigned Idx = 0;
   F.ModuleMapPath = ReadPath(F, Record, Idx);
 
-  if (F.Kind == MK_ExplicitModule) {
+  if (F.Kind == MK_ExplicitModule || F.Kind == MK_PrebuiltModule) {
     // For an explicitly-loaded module, we don't care whether the original
     // module map file exists or matches.
     return Success;
@@ -3404,6 +3513,31 @@ void ASTReader::makeModuleVisible(Module *Mod,
   }
 }
 
+/// We've merged the definition \p MergedDef into the existing definition
+/// \p Def. Ensure that \p Def is made visible whenever \p MergedDef is made
+/// visible.
+void ASTReader::mergeDefinitionVisibility(NamedDecl *Def,
+                                          NamedDecl *MergedDef) {
+  // FIXME: This doesn't correctly handle the case where MergedDef is visible
+  // in modules other than its owning module. We should instead give the
+  // ASTContext a list of merged definitions for Def.
+  if (Def->isHidden()) {
+    // If MergedDef is visible or becomes visible, make the definition visible.
+    if (!MergedDef->isHidden())
+      Def->Hidden = false;
+    else if (getContext().getLangOpts().ModulesLocalVisibility) {
+      getContext().mergeDefinitionIntoModule(
+          Def, MergedDef->getImportedOwningModule(),
+          /*NotifyListeners*/ false);
+      PendingMergedDefinitionsToDeduplicate.insert(Def);
+    } else {
+      auto SubmoduleID = MergedDef->getOwningModuleID();
+      assert(SubmoduleID && "hidden definition in no module");
+      HiddenNamesMap[getSubmodule(SubmoduleID)].push_back(Def);
+    }
+  }
+}
+
 bool ASTReader::loadGlobalIndex() {
   if (GlobalIndex)
     return false;
@@ -3411,7 +3545,7 @@ bool ASTReader::loadGlobalIndex() {
   if (TriedLoadingGlobalIndex || !UseGlobalIndex ||
       !Context.getLangOpts().Modules)
     return true;
-  
+
   // Try to load the global index.
   TriedLoadingGlobalIndex = true;
   StringRef ModuleCachePath
@@ -3445,7 +3579,7 @@ static void updateModuleTimestamp(ModuleFile &MF) {
 /// cursor into the start of the given block ID, returning false on success and
 /// true on failure.
 static bool SkipCursorToBlock(BitstreamCursor &Cursor, unsigned BlockID) {
-  while (1) {
+  while (true) {
     llvm::BitstreamEntry Entry = Cursor.advance();
     switch (Entry.Kind) {
     case llvm::BitstreamEntry::Error:
@@ -3474,7 +3608,8 @@ static bool SkipCursorToBlock(BitstreamCursor &Cursor, unsigned BlockID) {
 ASTReader::ASTReadResult ASTReader::ReadAST(StringRef FileName,
                                             ModuleKind Type,
                                             SourceLocation ImportLoc,
-                                            unsigned ClientLoadCapabilities) {
+                                            unsigned ClientLoadCapabilities,
+                                            SmallVectorImpl<ImportedSubmodule> *Imported) {
   llvm::SaveAndRestore<SourceLocation>
     SetCurImportLocRAII(CurrentImportLoc, ImportLoc);
 
@@ -3534,12 +3669,12 @@ ASTReader::ASTReadResult ASTReader::ReadAST(StringRef FileName,
         return Result;
     }
 
-    // Once read, set the ModuleFile bit base offset and update the size in 
+    // Once read, set the ModuleFile bit base offset and update the size in
     // bits of all files we've seen.
     F.GlobalBitOffset = TotalModulesSizeInBits;
     TotalModulesSizeInBits += F.SizeInBits;
     GlobalBitOffsetsMap.insert(std::make_pair(F.GlobalBitOffset, &F));
-    
+
     // Preload SLocEntries.
     for (unsigned I = 0, N = F.PreloadSLocEntries.size(); I != N; ++I) {
       int Index = int(F.PreloadSLocEntries[I] - 1) + F.SLocEntryBaseID;
@@ -3592,7 +3727,8 @@ ASTReader::ASTReadResult ASTReader::ReadAST(StringRef FileName,
   }
 
   if (!Context.getLangOpts().CPlusPlus ||
-      (Type != MK_ImplicitModule && Type != MK_ExplicitModule)) {
+      (Type != MK_ImplicitModule && Type != MK_ExplicitModule &&
+       Type != MK_PrebuiltModule)) {
     // Mark all of the identifiers in the identifier table as being out of date,
     // so that various accessors know to check the loaded modules when the
     // identifier is used.
@@ -3608,7 +3744,7 @@ ASTReader::ASTReadResult ASTReader::ReadAST(StringRef FileName,
   // Mark selectors as out of date.
   for (auto Sel : SelectorGeneration)
     SelectorOutOfDate[Sel.first] = true;
-  
+
   // Resolve any unresolved module exports.
   for (unsigned I = 0, N = UnresolvedModuleRefs.size(); I != N; ++I) {
     UnresolvedModuleRef &Unresolved = UnresolvedModuleRefs[I];
@@ -3639,10 +3775,14 @@ ASTReader::ASTReadResult ASTReader::ReadAST(StringRef FileName,
   }
   UnresolvedModuleRefs.clear();
 
+  if (Imported)
+    Imported->append(ImportedModules.begin(),
+                     ImportedModules.end());
+
   // FIXME: How do we load the 'use'd modules? They may not be submodules.
   // Might be unnecessary as use declarations are only used to build the
   // module itself.
-  
+
   InitializeContext();
 
   if (SemaObj)
@@ -3653,7 +3793,7 @@ ASTReader::ASTReadResult ASTReader::ReadAST(StringRef FileName,
 
   ModuleFile &PrimaryModule = ModuleMgr.getPrimaryModule();
   if (PrimaryModule.OriginalSourceFileID.isValid()) {
-    PrimaryModule.OriginalSourceFileID 
+    PrimaryModule.OriginalSourceFileID
       = FileID::get(PrimaryModule.SLocEntryBaseID
                     + PrimaryModule.OriginalSourceFileID.getOpaqueValue() - 1);
 
@@ -3666,11 +3806,11 @@ ASTReader::ASTReadResult ASTReader::ReadAST(StringRef FileName,
       SourceMgr.setMainFileID(PrimaryModule.OriginalSourceFileID);
     }
   }
-  
+
   // For any Objective-C class definitions we have already loaded, make sure
   // that we load any additional categories.
   for (unsigned I = 0, N = ObjCClassesLoaded.size(); I != N; ++I) {
-    loadObjCCategories(ObjCClassesLoaded[I]->getGlobalID(), 
+    loadObjCCategories(ObjCClassesLoaded[I]->getGlobalID(),
                        ObjCClassesLoaded[I],
                        PreviousGeneration);
   }
@@ -3693,11 +3833,12 @@ ASTReader::ASTReadResult ASTReader::ReadAST(StringRef FileName,
   return Success;
 }
 
-static ASTFileSignature readASTFileSignature(llvm::BitstreamReader &StreamFile);
+static ASTFileSignature readASTFileSignature(StringRef PCH);
 
 /// \brief Whether \p Stream starts with the AST/PCH file magic number 'CPCH'.
 static bool startsWithASTFileMagic(BitstreamCursor &Stream) {
-  return Stream.Read(8) == 'C' &&
+  return Stream.canSkipToPos(4) &&
+         Stream.Read(8) == 'C' &&
          Stream.Read(8) == 'P' &&
          Stream.Read(8) == 'C' &&
          Stream.Read(8) == 'H';
@@ -3709,6 +3850,7 @@ static unsigned moduleKindForDiagnostic(ModuleKind Kind) {
     return 0; // PCH
   case MK_ImplicitModule:
   case MK_ExplicitModule:
+  case MK_PrebuiltModule:
     return 1; // module
   case MK_MainFile:
   case MK_Preamble:
@@ -3750,7 +3892,7 @@ ASTReader::ReadASTCore(StringRef FileName,
 
     // Otherwise, return an error.
     Diag(diag::err_module_file_not_found) << moduleKindForDiagnostic(Type)
-                                          << FileName << ErrorStr.empty()
+                                          << FileName << !ErrorStr.empty()
                                           << ErrorStr;
     return Failure;
 
@@ -3762,7 +3904,7 @@ ASTReader::ReadASTCore(StringRef FileName,
 
     // Otherwise, return an error.
     Diag(diag::err_module_file_out_of_date) << moduleKindForDiagnostic(Type)
-                                            << FileName << ErrorStr.empty()
+                                            << FileName << !ErrorStr.empty()
                                             << ErrorStr;
     return Failure;
   }
@@ -3778,10 +3920,9 @@ ASTReader::ReadASTCore(StringRef FileName,
 
   ModuleFile &F = *M;
   BitstreamCursor &Stream = F.Stream;
-  PCHContainerRdr.ExtractPCH(F.Buffer->getMemBufferRef(), F.StreamFile);
-  Stream.init(&F.StreamFile);
+  Stream = BitstreamCursor(PCHContainerRdr.ExtractPCH(*F.Buffer));
   F.SizeInBits = F.Buffer->getBufferSize() * 8;
-  
+
   // Sniff for the signature.
   if (!startsWithASTFileMagic(Stream)) {
     Diag(diag::err_module_file_invalid) << moduleKindForDiagnostic(Type)
@@ -3791,16 +3932,16 @@ ASTReader::ReadASTCore(StringRef FileName,
 
   // This is used for compatibility with older PCH formats.
   bool HaveReadControlBlock = false;
-  while (1) {
+  while (true) {
     llvm::BitstreamEntry Entry = Stream.advance();
-    
+
     switch (Entry.Kind) {
     case llvm::BitstreamEntry::Error:
     case llvm::BitstreamEntry::Record:
     case llvm::BitstreamEntry::EndBlock:
       Error("invalid record at top-level of AST file");
       return Failure;
-        
+
     case llvm::BitstreamEntry::SubBlock:
       break;
     }
@@ -3814,7 +3955,8 @@ ASTReader::ReadASTCore(StringRef FileName,
         //
         // FIXME: Should we also perform the converse check? Loading a module as
         // a PCH file sort of works, but it's a bit wonky.
-        if ((Type == MK_ImplicitModule || Type == MK_ExplicitModule) &&
+        if ((Type == MK_ImplicitModule || Type == MK_ExplicitModule ||
+             Type == MK_PrebuiltModule) &&
             F.ModuleName.empty()) {
           auto Result = (Type == MK_ImplicitModule) ? OutOfDate : Failure;
           if (Result != OutOfDate ||
@@ -3930,26 +4072,26 @@ ASTReader::ASTReadResult ASTReader::ReadExtensionBlock(ModuleFile &F) {
 void ASTReader::InitializeContext() {
   // If there's a listener, notify them that we "read" the translation unit.
   if (DeserializationListener)
-    DeserializationListener->DeclRead(PREDEF_DECL_TRANSLATION_UNIT_ID, 
+    DeserializationListener->DeclRead(PREDEF_DECL_TRANSLATION_UNIT_ID,
                                       Context.getTranslationUnitDecl());
 
   // FIXME: Find a better way to deal with collisions between these
   // built-in types. Right now, we just ignore the problem.
-  
+
   // Load the special types.
   if (SpecialTypes.size() >= NumSpecialTypeIDs) {
     if (unsigned String = SpecialTypes[SPECIAL_TYPE_CF_CONSTANT_STRING]) {
       if (!Context.CFConstantStringTypeDecl)
         Context.setCFConstantStringType(GetType(String));
     }
-    
+
     if (unsigned File = SpecialTypes[SPECIAL_TYPE_FILE]) {
       QualType FileType = GetType(File);
       if (FileType.isNull()) {
         Error("FILE type is NULL");
         return;
       }
-      
+
       if (!Context.FILEDecl) {
         if (const TypedefType *Typedef = FileType->getAs<TypedefType>())
           Context.setFILEDecl(Typedef->getDecl());
@@ -3963,14 +4105,14 @@ void ASTReader::InitializeContext() {
         }
       }
     }
-    
+
     if (unsigned Jmp_buf = SpecialTypes[SPECIAL_TYPE_JMP_BUF]) {
       QualType Jmp_bufType = GetType(Jmp_buf);
       if (Jmp_bufType.isNull()) {
         Error("jmp_buf type is NULL");
         return;
       }
-      
+
       if (!Context.jmp_bufDecl) {
         if (const TypedefType *Typedef = Jmp_bufType->getAs<TypedefType>())
           Context.setjmp_bufDecl(Typedef->getDecl());
@@ -3984,14 +4126,14 @@ void ASTReader::InitializeContext() {
         }
       }
     }
-    
+
     if (unsigned Sigjmp_buf = SpecialTypes[SPECIAL_TYPE_SIGJMP_BUF]) {
       QualType Sigjmp_bufType = GetType(Sigjmp_buf);
       if (Sigjmp_bufType.isNull()) {
         Error("sigjmp_buf type is NULL");
         return;
       }
-      
+
       if (!Context.sigjmp_bufDecl) {
         if (const TypedefType *Typedef = Sigjmp_bufType->getAs<TypedefType>())
           Context.setsigjmp_bufDecl(Typedef->getDecl());
@@ -4039,7 +4181,7 @@ void ASTReader::InitializeContext() {
       }
     }
   }
-  
+
   ReadPragmaDiagnosticMappings(Context.getDiagnostics());
 
   // If there were any CUDA special declarations, deserialize them.
@@ -4067,10 +4209,10 @@ void ASTReader::finalizeForWriting() {
   // Nothing to do for now.
 }
 
-/// \brief Reads and return the signature record from \p StreamFile's control
-/// block, or else returns 0.
-static ASTFileSignature readASTFileSignature(llvm::BitstreamReader &StreamFile){
-  BitstreamCursor Stream(StreamFile);
+/// \brief Reads and return the signature record from \p PCH's control block, or
+/// else returns 0.
+static ASTFileSignature readASTFileSignature(StringRef PCH) {
+  BitstreamCursor Stream(PCH);
   if (!startsWithASTFileMagic(Stream))
     return 0;
 
@@ -4080,10 +4222,9 @@ static ASTFileSignature readASTFileSignature(llvm::BitstreamReader &StreamFile){
 
   // Scan for SIGNATURE inside the control block.
   ASTReader::RecordData Record;
-  while (1) {
+  while (true) {
     llvm::BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
-    if (Entry.Kind == llvm::BitstreamEntry::EndBlock ||
-        Entry.Kind != llvm::BitstreamEntry::Record)
+    if (Entry.Kind != llvm::BitstreamEntry::Record)
       return 0;
 
     Record.clear();
@@ -4108,16 +4249,14 @@ std::string ASTReader::getOriginalSourceFile(
   }
 
   // Initialize the stream
-  llvm::BitstreamReader StreamFile;
-  PCHContainerRdr.ExtractPCH((*Buffer)->getMemBufferRef(), StreamFile);
-  BitstreamCursor Stream(StreamFile);
+  BitstreamCursor Stream(PCHContainerRdr.ExtractPCH(**Buffer));
 
   // Sniff for the signature.
   if (!startsWithASTFileMagic(Stream)) {
     Diags.Report(diag::err_fe_not_a_pch_file) << ASTFileName;
     return std::string();
   }
-  
+
   // Scan for the CONTROL_BLOCK_ID block.
   if (SkipCursorToBlock(Stream, CONTROL_BLOCK_ID)) {
     Diags.Report(diag::err_fe_pch_malformed_block) << ASTFileName;
@@ -4126,16 +4265,16 @@ std::string ASTReader::getOriginalSourceFile(
 
   // Scan for ORIGINAL_FILE inside the control block.
   RecordData Record;
-  while (1) {
+  while (true) {
     llvm::BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
     if (Entry.Kind == llvm::BitstreamEntry::EndBlock)
       return std::string();
-    
+
     if (Entry.Kind != llvm::BitstreamEntry::Record) {
       Diags.Report(diag::err_fe_pch_malformed_block) << ASTFileName;
       return std::string();
     }
-    
+
     Record.clear();
     StringRef Blob;
     if (Stream.readRecord(Entry.ID, Record, &Blob) == ORIGINAL_FILE)
@@ -4144,6 +4283,7 @@ std::string ASTReader::getOriginalSourceFile(
 }
 
 namespace {
+
   class SimplePCHValidator : public ASTReaderListener {
     const LangOptions &ExistingLangOpts;
     const TargetOptions &ExistingTargetOpts;
@@ -4170,11 +4310,13 @@ namespace {
       return checkLanguageOptions(ExistingLangOpts, LangOpts, nullptr,
                                   AllowCompatibleDifferences);
     }
+
     bool ReadTargetOptions(const TargetOptions &TargetOpts, bool Complain,
                            bool AllowCompatibleDifferences) override {
       return checkTargetOptions(ExistingTargetOpts, TargetOpts, nullptr,
                                 AllowCompatibleDifferences);
     }
+
     bool ReadHeaderSearchOptions(const HeaderSearchOptions &HSOpts,
                                  StringRef SpecificModuleCachePath,
                                  bool Complain) override {
@@ -4182,6 +4324,7 @@ namespace {
                                       ExistingModuleCachePath,
                                       nullptr, ExistingLangOpts);
     }
+
     bool ReadPreprocessorOptions(const PreprocessorOptions &PPOpts,
                                  bool Complain,
                                  std::string &SuggestedPredefines) override {
@@ -4189,13 +4332,14 @@ namespace {
                                       SuggestedPredefines, ExistingLangOpts);
     }
   };
-}
+
+} // end anonymous namespace
 
 bool ASTReader::readASTFileControlBlock(
     StringRef Filename, FileManager &FileMgr,
     const PCHContainerReader &PCHContainerRdr,
     bool FindModuleFileExtensions,
-    ASTReaderListener &Listener) {
+    ASTReaderListener &Listener, bool ValidateDiagnosticOptions) {
   // Open the AST file.
   // FIXME: This allows use of the VFS; we do not allow use of the
   // VFS when actually loading a module.
@@ -4205,9 +4349,7 @@ bool ASTReader::readASTFileControlBlock(
   }
 
   // Initialize the stream
-  llvm::BitstreamReader StreamFile;
-  PCHContainerRdr.ExtractPCH((*Buffer)->getMemBufferRef(), StreamFile);
-  BitstreamCursor Stream(StreamFile);
+  BitstreamCursor Stream(PCHContainerRdr.ExtractPCH(**Buffer));
 
   // Sniff for the signature.
   if (!startsWithASTFileMagic(Stream))
@@ -4235,7 +4377,8 @@ bool ASTReader::readASTFileControlBlock(
         std::string IgnoredSuggestedPredefines;
         if (ReadOptionsBlock(Stream, ARR_ConfigurationMismatch | ARR_OutOfDate,
                              /*AllowCompatibleConfigurationMismatch*/ false,
-                             Listener, IgnoredSuggestedPredefines) != Success)
+                             Listener, IgnoredSuggestedPredefines,
+                             ValidateDiagnosticOptions) != Success)
           return true;
         break;
       }
@@ -4280,7 +4423,7 @@ bool ASTReader::readASTFileControlBlock(
 
       if (Listener.ReadFullVersionInformation(Blob))
         return true;
-      
+
       break;
     }
     case MODULE_NAME:
@@ -4408,7 +4551,8 @@ bool ASTReader::isAcceptableASTFile(
                                ExistingModuleCachePath, FileMgr);
   return !readASTFileControlBlock(Filename, FileMgr, PCHContainerRdr,
                                   /*FindModuleFileExtensions=*/false,
-                                  validator);
+                                  validator,
+                                  /*ValidateDiagnosticOptions=*/true);
 }
 
 ASTReader::ASTReadResult
@@ -4425,7 +4569,7 @@ ASTReader::ReadSubmoduleBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
   RecordData Record;
   while (true) {
     llvm::BitstreamEntry Entry = F.Stream.advanceSkippingSubblocks();
-    
+
     switch (Entry.Kind) {
     case llvm::BitstreamEntry::SubBlock: // Handled for us already.
     case llvm::BitstreamEntry::Error:
@@ -4523,7 +4667,7 @@ ASTReader::ReadSubmoduleBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       CurrentModule->ConfigMacrosExhaustive = ConfigMacrosExhaustive;
       if (DeserializationListener)
         DeserializationListener->ModuleRead(GlobalID, CurrentModule);
-      
+
       SubmodulesLoaded[GlobalIndex] = CurrentModule;
 
       // Clear out data that will be replaced by what is in the module file.
@@ -4563,7 +4707,7 @@ ASTReader::ReadSubmoduleBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       }
       break;
     }
-        
+
     case SUBMODULE_HEADER:
     case SUBMODULE_EXCLUDED_HEADER:
     case SUBMODULE_PRIVATE_HEADER:
@@ -4597,17 +4741,17 @@ ASTReader::ReadSubmoduleBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       }
       break;
     }
-        
+
     case SUBMODULE_METADATA: {
       F.BaseSubmoduleID = getTotalNumSubmodules();
       F.LocalNumSubmodules = Record[0];
       unsigned LocalBaseSubmoduleID = Record[1];
       if (F.LocalNumSubmodules > 0) {
-        // Introduce the global -> local mapping for submodules within this 
+        // Introduce the global -> local mapping for submodules within this
         // module.
         GlobalSubmoduleMap.insert(std::make_pair(getTotalNumSubmodules()+1,&F));
-        
-        // Introduce the local -> global mapping for submodules within this 
+
+        // Introduce the local -> global mapping for submodules within this
         // module.
         F.SubmoduleRemap.insertOrReplace(
           std::make_pair(LocalBaseSubmoduleID,
@@ -4617,7 +4761,7 @@ ASTReader::ReadSubmoduleBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       }
       break;
     }
-        
+
     case SUBMODULE_IMPORTS: {
       for (unsigned Idx = 0; Idx != Record.size(); ++Idx) {
         UnresolvedModuleRef Unresolved;
@@ -4641,8 +4785,8 @@ ASTReader::ReadSubmoduleBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
         Unresolved.IsWildcard = Record[Idx + 1];
         UnresolvedModuleRefs.push_back(Unresolved);
       }
-      
-      // Once we've loaded the set of exports, there's no reason to keep 
+
+      // Once we've loaded the set of exports, there's no reason to keep
       // the parsed, unresolved exports around.
       CurrentModule->UnresolvedExports.clear();
       break;
@@ -4673,6 +4817,13 @@ ASTReader::ReadSubmoduleBlock(ModuleFile &F, unsigned ClientLoadCapabilities) {
       UnresolvedModuleRefs.push_back(Unresolved);
       break;
     }
+
+    case SUBMODULE_INITIALIZERS:
+      SmallVector<uint32_t, 16> Inits;
+      for (auto &ID : Record)
+        Inits.push_back(getGlobalDeclID(F, ID));
+      Context.addLazyModuleInitializers(CurrentModule, Inits);
+      break;
     }
   }
 }
@@ -4848,7 +4999,7 @@ std::pair<ModuleFile *, unsigned>
 ASTReader::getModulePreprocessedEntity(unsigned GlobalIndex) {
   GlobalPreprocessedEntityMapType::iterator
   I = GlobalPreprocessedEntityMap.find(GlobalIndex);
-  assert(I != GlobalPreprocessedEntityMap.end() && 
+  assert(I != GlobalPreprocessedEntityMap.end() &&
          "Corrupted global preprocessed entity map");
   ModuleFile *M = I->second;
   unsigned LocalIndex = GlobalIndex - M->BasePreprocessedEntityID;
@@ -4884,8 +5035,8 @@ PreprocessedEntity *ASTReader::ReadPreprocessedEntity(unsigned Index) {
     Error("no preprocessing record");
     return nullptr;
   }
-  
-  SavedStreamPosition SavedPosition(M.PreprocessorDetailCursor);  
+
+  SavedStreamPosition SavedPosition(M.PreprocessorDetailCursor);
   M.PreprocessorDetailCursor.JumpToBit(PPOffs.BitOffset);
 
   llvm::BitstreamEntry Entry =
@@ -4924,7 +5075,7 @@ PreprocessedEntity *ASTReader::ReadPreprocessedEntity(unsigned Index) {
 
     return ME;
   }
-      
+
   case PPD_MACRO_DEFINITION: {
     // Decode the identifier info and then check again; if the macro is
     // still defined and associated with the identifier,
@@ -4936,14 +5087,14 @@ PreprocessedEntity *ASTReader::ReadPreprocessedEntity(unsigned Index) {
 
     return MD;
   }
-      
+
   case PPD_INCLUSION_DIRECTIVE: {
     const char *FullFileNameStart = Blob.data() + Record[0];
     StringRef FullFileName(FullFileNameStart, Blob.size() - Record[0]);
     const FileEntry *File = nullptr;
     if (!FullFileName.empty())
       File = PP.getFileManager().getFile(FullFileName);
-    
+
     // FIXME: Stable encoding
     InclusionDirective::InclusionKind Kind
       = static_cast<InclusionDirective::InclusionKind>(Record[2]);
@@ -5006,7 +5157,7 @@ struct PPEntityComp {
   }
 };
 
-}
+} // end anonymous namespace
 
 PreprocessedEntityID ASTReader::findPreprocessedEntity(SourceLocation Loc,
                                                        bool EndsAfter) const {
@@ -5084,11 +5235,11 @@ Optional<bool> ASTReader::isPreprocessedEntityInFileID(unsigned Index,
   ModuleFile &M = *PPInfo.first;
   unsigned LocalIndex = PPInfo.second;
   const PPEntityOffset &PPOffs = M.PreprocessedEntityOffsets[LocalIndex];
-  
+
   SourceLocation Loc = TranslateSourceLocation(M, PPOffs.getBegin());
   if (Loc.isInvalid())
     return false;
-  
+
   if (SourceMgr.isInFileID(SourceMgr.getFileLoc(Loc), FID))
     return true;
   else
@@ -5096,12 +5247,13 @@ Optional<bool> ASTReader::isPreprocessedEntityInFileID(unsigned Index,
 }
 
 namespace {
+
   /// \brief Visitor used to search for information about a header file.
   class HeaderFileInfoVisitor {
     const FileEntry *FE;
-    
+
     Optional<HeaderFileInfo> HFI;
-    
+
   public:
     explicit HeaderFileInfoVisitor(const FileEntry *FE)
       : FE(FE) { }
@@ -5120,17 +5272,18 @@ namespace {
       HFI = *Pos;
       return true;
     }
-    
+
     Optional<HeaderFileInfo> getHeaderFileInfo() const { return HFI; }
   };
-}
+
+} // end anonymous namespace
 
 HeaderFileInfo ASTReader::GetHeaderFileInfo(const FileEntry *FE) {
   HeaderFileInfoVisitor Visitor(FE);
   ModuleMgr.visit(Visitor);
   if (Optional<HeaderFileInfo> HFI = Visitor.getHeaderFileInfo())
     return *HFI;
-  
+
   return HeaderFileInfo();
 }
 
@@ -5152,7 +5305,7 @@ void ASTReader::ReadPragmaDiagnosticMappings(DiagnosticsEngine &Diag) {
                     FullSourceLoc(Loc, SourceMgr)));
         continue;
       }
-      
+
       assert(DiagStateID == 0);
       // A new DiagState was created here.
       Diag.DiagStates.push_back(*Diag.GetCurDiagState());
@@ -5161,7 +5314,7 @@ void ASTReader::ReadPragmaDiagnosticMappings(DiagnosticsEngine &Diag) {
       Diag.DiagStatePoints.push_back(
           DiagnosticsEngine::DiagStatePoint(NewState,
                                             FullSourceLoc(Loc, SourceMgr)));
-      while (1) {
+      while (true) {
         assert(Idx < F.PragmaDiagMappings.size() &&
                "Invalid data, didn't find '-1' marking end of diag/map pairs");
         if (Idx >= F.PragmaDiagMappings.size()) {
@@ -5298,7 +5451,7 @@ QualType ASTReader::readTypeRecord(unsigned Index) {
     QualType ClassType = readType(*Loc.F, Record, Idx);
     if (PointeeType.isNull() || ClassType.isNull())
       return QualType();
-    
+
     return Context.getMemberPointerType(PointeeType, ClassType.getTypePtr());
   }
 
@@ -5408,7 +5561,7 @@ QualType ASTReader::readTypeRecord(unsigned Index) {
     return Context.getTypeDeclType(
                   ReadDeclAs<UnresolvedUsingTypenameDecl>(*Loc.F, Record, Idx));
   }
-      
+
   case TYPE_TYPEDEF: {
     if (Record.size() != 2) {
       Error("incorrect encoding of typedef type");
@@ -5529,6 +5682,16 @@ QualType ASTReader::readTypeRecord(unsigned Index) {
     return Context.getObjCInterfaceType(ItfD->getCanonicalDecl());
   }
 
+  case TYPE_OBJC_TYPE_PARAM: {
+    unsigned Idx = 0;
+    ObjCTypeParamDecl *Decl
+      = ReadDeclAs<ObjCTypeParamDecl>(*Loc.F, Record, Idx);
+    unsigned NumProtos = Record[Idx++];
+    SmallVector<ObjCProtocolDecl*, 4> Protos;
+    for (unsigned I = 0; I != NumProtos; ++I)
+      Protos.push_back(ReadDeclAs<ObjCProtocolDecl>(*Loc.F, Record, Idx));
+    return Context.getObjCTypeParamType(Decl, Protos);
+  }
   case TYPE_OBJC_OBJECT: {
     unsigned Idx = 0;
     QualType Base = readType(*Loc.F, Record, Idx);
@@ -5666,15 +5829,17 @@ QualType ASTReader::readTypeRecord(unsigned Index) {
   }
 
   case TYPE_PIPE: {
-    if (Record.size() != 1) {
+    if (Record.size() != 2) {
       Error("Incorrect encoding of pipe type");
       return QualType();
     }
 
     // Reading the pipe element type.
     QualType ElementType = readType(*Loc.F, Record, Idx);
-    return Context.getPipeType(ElementType);
+    unsigned ReadOnly = Record[1];
+    return Context.getPipeType(ElementType, ReadOnly);
   }
+
   }
   llvm_unreachable("Invalid TypeCode!");
 }
@@ -5701,26 +5866,27 @@ void ASTReader::readExceptionSpec(ModuleFile &ModuleFile,
 }
 
 class clang::TypeLocReader : public TypeLocVisitor<TypeLocReader> {
-  ASTReader &Reader;
-  ModuleFile &F;
+  ModuleFile *F;
+  ASTReader *Reader;
   const ASTReader::RecordData &Record;
   unsigned &Idx;
 
-  SourceLocation ReadSourceLocation(const ASTReader::RecordData &R,
-                                    unsigned &I) {
-    return Reader.ReadSourceLocation(F, R, I);
+  SourceLocation ReadSourceLocation() {
+    return Reader->ReadSourceLocation(*F, Record, Idx);
   }
 
-  template<typename T>
-  T *ReadDeclAs(const ASTReader::RecordData &Record, unsigned &Idx) {
-    return Reader.ReadDeclAs<T>(F, Record, Idx);
+  TypeSourceInfo *GetTypeSourceInfo() {
+    return Reader->GetTypeSourceInfo(*F, Record, Idx);
   }
-  
+
+  NestedNameSpecifierLoc ReadNestedNameSpecifierLoc() {
+    return Reader->ReadNestedNameSpecifierLoc(*F, Record, Idx);
+  }
+
 public:
-  TypeLocReader(ASTReader &Reader, ModuleFile &F,
+  TypeLocReader(ModuleFile &F, ASTReader &Reader,
                 const ASTReader::RecordData &Record, unsigned &Idx)
-    : Reader(Reader), F(F), Record(Record), Idx(Idx)
-  { }
+      : F(&F), Reader(&Reader), Record(Record), Idx(Idx) {}
 
   // We want compile-time assurance that we've enumerated all of
   // these, so unfortunately we have to declare them first, then
@@ -5737,8 +5903,9 @@ public:
 void TypeLocReader::VisitQualifiedTypeLoc(QualifiedTypeLoc TL) {
   // nothing to do
 }
+
 void TypeLocReader::VisitBuiltinTypeLoc(BuiltinTypeLoc TL) {
-  TL.setBuiltinLoc(ReadSourceLocation(Record, Idx));
+  TL.setBuiltinLoc(ReadSourceLocation());
   if (TL.needsExtraLocalData()) {
     TL.setWrittenTypeSpec(static_cast<DeclSpec::TST>(Record[Idx++]));
     TL.setWrittenSignSpec(static_cast<DeclSpec::TSS>(Record[Idx++]));
@@ -5746,219 +5913,264 @@ void TypeLocReader::VisitBuiltinTypeLoc(BuiltinTypeLoc TL) {
     TL.setModeAttr(Record[Idx++]);
   }
 }
+
 void TypeLocReader::VisitComplexTypeLoc(ComplexTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitPointerTypeLoc(PointerTypeLoc TL) {
-  TL.setStarLoc(ReadSourceLocation(Record, Idx));
+  TL.setStarLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitDecayedTypeLoc(DecayedTypeLoc TL) {
   // nothing to do
 }
+
 void TypeLocReader::VisitAdjustedTypeLoc(AdjustedTypeLoc TL) {
   // nothing to do
 }
+
 void TypeLocReader::VisitBlockPointerTypeLoc(BlockPointerTypeLoc TL) {
-  TL.setCaretLoc(ReadSourceLocation(Record, Idx));
+  TL.setCaretLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitLValueReferenceTypeLoc(LValueReferenceTypeLoc TL) {
-  TL.setAmpLoc(ReadSourceLocation(Record, Idx));
+  TL.setAmpLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitRValueReferenceTypeLoc(RValueReferenceTypeLoc TL) {
-  TL.setAmpAmpLoc(ReadSourceLocation(Record, Idx));
+  TL.setAmpAmpLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitMemberPointerTypeLoc(MemberPointerTypeLoc TL) {
-  TL.setStarLoc(ReadSourceLocation(Record, Idx));
-  TL.setClassTInfo(Reader.GetTypeSourceInfo(F, Record, Idx));
+  TL.setStarLoc(ReadSourceLocation());
+  TL.setClassTInfo(GetTypeSourceInfo());
 }
+
 void TypeLocReader::VisitArrayTypeLoc(ArrayTypeLoc TL) {
-  TL.setLBracketLoc(ReadSourceLocation(Record, Idx));
-  TL.setRBracketLoc(ReadSourceLocation(Record, Idx));
+  TL.setLBracketLoc(ReadSourceLocation());
+  TL.setRBracketLoc(ReadSourceLocation());
   if (Record[Idx++])
-    TL.setSizeExpr(Reader.ReadExpr(F));
+    TL.setSizeExpr(Reader->ReadExpr(*F));
   else
     TL.setSizeExpr(nullptr);
 }
+
 void TypeLocReader::VisitConstantArrayTypeLoc(ConstantArrayTypeLoc TL) {
   VisitArrayTypeLoc(TL);
 }
+
 void TypeLocReader::VisitIncompleteArrayTypeLoc(IncompleteArrayTypeLoc TL) {
   VisitArrayTypeLoc(TL);
 }
+
 void TypeLocReader::VisitVariableArrayTypeLoc(VariableArrayTypeLoc TL) {
   VisitArrayTypeLoc(TL);
 }
+
 void TypeLocReader::VisitDependentSizedArrayTypeLoc(
                                             DependentSizedArrayTypeLoc TL) {
   VisitArrayTypeLoc(TL);
 }
+
 void TypeLocReader::VisitDependentSizedExtVectorTypeLoc(
                                         DependentSizedExtVectorTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitVectorTypeLoc(VectorTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitExtVectorTypeLoc(ExtVectorTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitFunctionTypeLoc(FunctionTypeLoc TL) {
-  TL.setLocalRangeBegin(ReadSourceLocation(Record, Idx));
-  TL.setLParenLoc(ReadSourceLocation(Record, Idx));
-  TL.setRParenLoc(ReadSourceLocation(Record, Idx));
-  TL.setLocalRangeEnd(ReadSourceLocation(Record, Idx));
+  TL.setLocalRangeBegin(ReadSourceLocation());
+  TL.setLParenLoc(ReadSourceLocation());
+  TL.setRParenLoc(ReadSourceLocation());
+  TL.setLocalRangeEnd(ReadSourceLocation());
   for (unsigned i = 0, e = TL.getNumParams(); i != e; ++i) {
-    TL.setParam(i, ReadDeclAs<ParmVarDecl>(Record, Idx));
+    TL.setParam(i, Reader->ReadDeclAs<ParmVarDecl>(*F, Record, Idx));
   }
 }
+
 void TypeLocReader::VisitFunctionProtoTypeLoc(FunctionProtoTypeLoc TL) {
   VisitFunctionTypeLoc(TL);
 }
+
 void TypeLocReader::VisitFunctionNoProtoTypeLoc(FunctionNoProtoTypeLoc TL) {
   VisitFunctionTypeLoc(TL);
 }
 void TypeLocReader::VisitUnresolvedUsingTypeLoc(UnresolvedUsingTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
 void TypeLocReader::VisitTypedefTypeLoc(TypedefTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
 void TypeLocReader::VisitTypeOfExprTypeLoc(TypeOfExprTypeLoc TL) {
-  TL.setTypeofLoc(ReadSourceLocation(Record, Idx));
-  TL.setLParenLoc(ReadSourceLocation(Record, Idx));
-  TL.setRParenLoc(ReadSourceLocation(Record, Idx));
+  TL.setTypeofLoc(ReadSourceLocation());
+  TL.setLParenLoc(ReadSourceLocation());
+  TL.setRParenLoc(ReadSourceLocation());
 }
 void TypeLocReader::VisitTypeOfTypeLoc(TypeOfTypeLoc TL) {
-  TL.setTypeofLoc(ReadSourceLocation(Record, Idx));
-  TL.setLParenLoc(ReadSourceLocation(Record, Idx));
-  TL.setRParenLoc(ReadSourceLocation(Record, Idx));
-  TL.setUnderlyingTInfo(Reader.GetTypeSourceInfo(F, Record, Idx));
+  TL.setTypeofLoc(ReadSourceLocation());
+  TL.setLParenLoc(ReadSourceLocation());
+  TL.setRParenLoc(ReadSourceLocation());
+  TL.setUnderlyingTInfo(GetTypeSourceInfo());
 }
 void TypeLocReader::VisitDecltypeTypeLoc(DecltypeTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitUnaryTransformTypeLoc(UnaryTransformTypeLoc TL) {
-  TL.setKWLoc(ReadSourceLocation(Record, Idx));
-  TL.setLParenLoc(ReadSourceLocation(Record, Idx));
-  TL.setRParenLoc(ReadSourceLocation(Record, Idx));
-  TL.setUnderlyingTInfo(Reader.GetTypeSourceInfo(F, Record, Idx));
+  TL.setKWLoc(ReadSourceLocation());
+  TL.setLParenLoc(ReadSourceLocation());
+  TL.setRParenLoc(ReadSourceLocation());
+  TL.setUnderlyingTInfo(GetTypeSourceInfo());
 }
+
 void TypeLocReader::VisitAutoTypeLoc(AutoTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitRecordTypeLoc(RecordTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitEnumTypeLoc(EnumTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitAttributedTypeLoc(AttributedTypeLoc TL) {
-  TL.setAttrNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setAttrNameLoc(ReadSourceLocation());
   if (TL.hasAttrOperand()) {
     SourceRange range;
-    range.setBegin(ReadSourceLocation(Record, Idx));
-    range.setEnd(ReadSourceLocation(Record, Idx));
+    range.setBegin(ReadSourceLocation());
+    range.setEnd(ReadSourceLocation());
     TL.setAttrOperandParensRange(range);
   }
   if (TL.hasAttrExprOperand()) {
     if (Record[Idx++])
-      TL.setAttrExprOperand(Reader.ReadExpr(F));
+      TL.setAttrExprOperand(Reader->ReadExpr(*F));
     else
       TL.setAttrExprOperand(nullptr);
   } else if (TL.hasAttrEnumOperand())
-    TL.setAttrEnumOperandLoc(ReadSourceLocation(Record, Idx));
+    TL.setAttrEnumOperandLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitTemplateTypeParmTypeLoc(TemplateTypeParmTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitSubstTemplateTypeParmTypeLoc(
                                             SubstTemplateTypeParmTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
 void TypeLocReader::VisitSubstTemplateTypeParmPackTypeLoc(
                                           SubstTemplateTypeParmPackTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
 void TypeLocReader::VisitTemplateSpecializationTypeLoc(
                                            TemplateSpecializationTypeLoc TL) {
-  TL.setTemplateKeywordLoc(ReadSourceLocation(Record, Idx));
-  TL.setTemplateNameLoc(ReadSourceLocation(Record, Idx));
-  TL.setLAngleLoc(ReadSourceLocation(Record, Idx));
-  TL.setRAngleLoc(ReadSourceLocation(Record, Idx));
+  TL.setTemplateKeywordLoc(ReadSourceLocation());
+  TL.setTemplateNameLoc(ReadSourceLocation());
+  TL.setLAngleLoc(ReadSourceLocation());
+  TL.setRAngleLoc(ReadSourceLocation());
   for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
-    TL.setArgLocInfo(i,
-        Reader.GetTemplateArgumentLocInfo(F,
-                                          TL.getTypePtr()->getArg(i).getKind(),
-                                          Record, Idx));
+    TL.setArgLocInfo(
+        i,
+        Reader->GetTemplateArgumentLocInfo(
+            *F, TL.getTypePtr()->getArg(i).getKind(), Record, Idx));
 }
 void TypeLocReader::VisitParenTypeLoc(ParenTypeLoc TL) {
-  TL.setLParenLoc(ReadSourceLocation(Record, Idx));
-  TL.setRParenLoc(ReadSourceLocation(Record, Idx));
+  TL.setLParenLoc(ReadSourceLocation());
+  TL.setRParenLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitElaboratedTypeLoc(ElaboratedTypeLoc TL) {
-  TL.setElaboratedKeywordLoc(ReadSourceLocation(Record, Idx));
-  TL.setQualifierLoc(Reader.ReadNestedNameSpecifierLoc(F, Record, Idx));
+  TL.setElaboratedKeywordLoc(ReadSourceLocation());
+  TL.setQualifierLoc(ReadNestedNameSpecifierLoc());
 }
+
 void TypeLocReader::VisitInjectedClassNameTypeLoc(InjectedClassNameTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitDependentNameTypeLoc(DependentNameTypeLoc TL) {
-  TL.setElaboratedKeywordLoc(ReadSourceLocation(Record, Idx));
-  TL.setQualifierLoc(Reader.ReadNestedNameSpecifierLoc(F, Record, Idx));
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setElaboratedKeywordLoc(ReadSourceLocation());
+  TL.setQualifierLoc(ReadNestedNameSpecifierLoc());
+  TL.setNameLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitDependentTemplateSpecializationTypeLoc(
        DependentTemplateSpecializationTypeLoc TL) {
-  TL.setElaboratedKeywordLoc(ReadSourceLocation(Record, Idx));
-  TL.setQualifierLoc(Reader.ReadNestedNameSpecifierLoc(F, Record, Idx));
-  TL.setTemplateKeywordLoc(ReadSourceLocation(Record, Idx));
-  TL.setTemplateNameLoc(ReadSourceLocation(Record, Idx));
-  TL.setLAngleLoc(ReadSourceLocation(Record, Idx));
-  TL.setRAngleLoc(ReadSourceLocation(Record, Idx));
+  TL.setElaboratedKeywordLoc(ReadSourceLocation());
+  TL.setQualifierLoc(ReadNestedNameSpecifierLoc());
+  TL.setTemplateKeywordLoc(ReadSourceLocation());
+  TL.setTemplateNameLoc(ReadSourceLocation());
+  TL.setLAngleLoc(ReadSourceLocation());
+  TL.setRAngleLoc(ReadSourceLocation());
   for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I)
-    TL.setArgLocInfo(I,
-        Reader.GetTemplateArgumentLocInfo(F,
-                                          TL.getTypePtr()->getArg(I).getKind(),
-                                          Record, Idx));
+    TL.setArgLocInfo(
+        I,
+        Reader->GetTemplateArgumentLocInfo(
+            *F, TL.getTypePtr()->getArg(I).getKind(), Record, Idx));
 }
+
 void TypeLocReader::VisitPackExpansionTypeLoc(PackExpansionTypeLoc TL) {
-  TL.setEllipsisLoc(ReadSourceLocation(Record, Idx));
+  TL.setEllipsisLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitObjCInterfaceTypeLoc(ObjCInterfaceTypeLoc TL) {
-  TL.setNameLoc(ReadSourceLocation(Record, Idx));
+  TL.setNameLoc(ReadSourceLocation());
 }
+
+void TypeLocReader::VisitObjCTypeParamTypeLoc(ObjCTypeParamTypeLoc TL) {
+  if (TL.getNumProtocols()) {
+    TL.setProtocolLAngleLoc(ReadSourceLocation());
+    TL.setProtocolRAngleLoc(ReadSourceLocation());
+  }
+  for (unsigned i = 0, e = TL.getNumProtocols(); i != e; ++i)
+    TL.setProtocolLoc(i, ReadSourceLocation());
+}
+
 void TypeLocReader::VisitObjCObjectTypeLoc(ObjCObjectTypeLoc TL) {
   TL.setHasBaseTypeAsWritten(Record[Idx++]);
-  TL.setTypeArgsLAngleLoc(ReadSourceLocation(Record, Idx));
-  TL.setTypeArgsRAngleLoc(ReadSourceLocation(Record, Idx));
+  TL.setTypeArgsLAngleLoc(ReadSourceLocation());
+  TL.setTypeArgsRAngleLoc(ReadSourceLocation());
   for (unsigned i = 0, e = TL.getNumTypeArgs(); i != e; ++i)
-    TL.setTypeArgTInfo(i, Reader.GetTypeSourceInfo(F, Record, Idx));
-  TL.setProtocolLAngleLoc(ReadSourceLocation(Record, Idx));
-  TL.setProtocolRAngleLoc(ReadSourceLocation(Record, Idx));
+    TL.setTypeArgTInfo(i, GetTypeSourceInfo());
+  TL.setProtocolLAngleLoc(ReadSourceLocation());
+  TL.setProtocolRAngleLoc(ReadSourceLocation());
   for (unsigned i = 0, e = TL.getNumProtocols(); i != e; ++i)
-    TL.setProtocolLoc(i, ReadSourceLocation(Record, Idx));
+    TL.setProtocolLoc(i, ReadSourceLocation());
 }
+
 void TypeLocReader::VisitObjCObjectPointerTypeLoc(ObjCObjectPointerTypeLoc TL) {
-  TL.setStarLoc(ReadSourceLocation(Record, Idx));
+  TL.setStarLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitAtomicTypeLoc(AtomicTypeLoc TL) {
-  TL.setKWLoc(ReadSourceLocation(Record, Idx));
-  TL.setLParenLoc(ReadSourceLocation(Record, Idx));
-  TL.setRParenLoc(ReadSourceLocation(Record, Idx));
+  TL.setKWLoc(ReadSourceLocation());
+  TL.setLParenLoc(ReadSourceLocation());
+  TL.setRParenLoc(ReadSourceLocation());
 }
+
 void TypeLocReader::VisitPipeTypeLoc(PipeTypeLoc TL) {
-  TL.setKWLoc(ReadSourceLocation(Record, Idx));
+  TL.setKWLoc(ReadSourceLocation());
 }
 
-TypeSourceInfo *ASTReader::GetTypeSourceInfo(ModuleFile &F,
-                                             const RecordData &Record,
-                                             unsigned &Idx) {
+TypeSourceInfo *
+ASTReader::GetTypeSourceInfo(ModuleFile &F, const ASTReader::RecordData &Record,
+                             unsigned &Idx) {
   QualType InfoTy = readType(F, Record, Idx);
   if (InfoTy.isNull())
     return nullptr;
 
   TypeSourceInfo *TInfo = getContext().CreateTypeSourceInfo(InfoTy);
-  TypeLocReader TLR(*this, F, Record, Idx);
+  TypeLocReader TLR(F, *this, Record, Idx);
   for (TypeLoc TL = TInfo->getTypeLoc(); !TL.isNull(); TL = TL.getNextTypeLoc())
     TLR.Visit(TL);
   return TInfo;
@@ -6141,18 +6353,18 @@ QualType ASTReader::getLocalType(ModuleFile &F, unsigned LocalID) {
   return GetType(getGlobalTypeID(F, LocalID));
 }
 
-serialization::TypeID 
+serialization::TypeID
 ASTReader::getGlobalTypeID(ModuleFile &F, unsigned LocalID) const {
   unsigned FastQuals = LocalID & Qualifiers::FastMask;
   unsigned LocalIndex = LocalID >> Qualifiers::FastWidth;
-  
+
   if (LocalIndex < NUM_PREDEF_TYPE_IDS)
     return LocalID;
 
   ContinuousRangeMap<uint32_t, int, 2>::iterator I
     = F.TypeRemap.find(LocalIndex - NUM_PREDEF_TYPE_IDS);
   assert(I != F.TypeRemap.end() && "Invalid index into type index remap");
-  
+
   unsigned GlobalIndex = LocalIndex + I->second;
   return (GlobalIndex << Qualifiers::FastWidth) | FastQuals;
 }
@@ -6168,18 +6380,18 @@ ASTReader::GetTemplateArgumentLocInfo(ModuleFile &F,
   case TemplateArgument::Type:
     return GetTypeSourceInfo(F, Record, Index);
   case TemplateArgument::Template: {
-    NestedNameSpecifierLoc QualifierLoc = ReadNestedNameSpecifierLoc(F, Record, 
+    NestedNameSpecifierLoc QualifierLoc = ReadNestedNameSpecifierLoc(F, Record,
                                                                      Index);
     SourceLocation TemplateNameLoc = ReadSourceLocation(F, Record, Index);
     return TemplateArgumentLocInfo(QualifierLoc, TemplateNameLoc,
                                    SourceLocation());
   }
   case TemplateArgument::TemplateExpansion: {
-    NestedNameSpecifierLoc QualifierLoc = ReadNestedNameSpecifierLoc(F, Record, 
+    NestedNameSpecifierLoc QualifierLoc = ReadNestedNameSpecifierLoc(F, Record,
                                                                      Index);
     SourceLocation TemplateNameLoc = ReadSourceLocation(F, Record, Index);
     SourceLocation EllipsisLoc = ReadSourceLocation(F, Record, Index);
-    return TemplateArgumentLocInfo(QualifierLoc, TemplateNameLoc, 
+    return TemplateArgumentLocInfo(QualifierLoc, TemplateNameLoc,
                                    EllipsisLoc);
   }
   case TemplateArgument::Null:
@@ -6324,7 +6536,7 @@ CXXBaseSpecifier *ASTReader::GetExternalCXXBaseSpecifiers(uint64_t Offset) {
   return Bases;
 }
 
-serialization::DeclID 
+serialization::DeclID
 ASTReader::getGlobalDeclID(ModuleFile &F, LocalDeclID LocalID) const {
   if (LocalID < NUM_PREDEF_DECL_IDS)
     return LocalID;
@@ -6332,7 +6544,7 @@ ASTReader::getGlobalDeclID(ModuleFile &F, LocalDeclID LocalID) const {
   ContinuousRangeMap<uint32_t, int, 2>::iterator I
     = F.DeclRemap.find(LocalID - NUM_PREDEF_DECL_IDS);
   assert(I != F.DeclRemap.end() && "Invalid index into decl index remap");
-  
+
   return LocalID + I->second;
 }
 
@@ -6342,7 +6554,7 @@ bool ASTReader::isDeclIDFromModule(serialization::GlobalDeclID ID,
   if (ID < NUM_PREDEF_DECL_IDS)
     return false;
 
-  return ID - NUM_PREDEF_DECL_IDS >= M.BaseDeclID && 
+  return ID - NUM_PREDEF_DECL_IDS >= M.BaseDeclID &&
          ID - NUM_PREDEF_DECL_IDS < M.BaseDeclID + M.LocalNumDecls;
 }
 
@@ -6474,11 +6686,11 @@ Decl *ASTReader::GetDecl(DeclID ID) {
   return DeclsLoaded[Index];
 }
 
-DeclID ASTReader::mapGlobalIDToModuleFileGlobalID(ModuleFile &M, 
+DeclID ASTReader::mapGlobalIDToModuleFileGlobalID(ModuleFile &M,
                                                   DeclID GlobalID) {
   if (GlobalID < NUM_PREDEF_DECL_IDS)
     return GlobalID;
-  
+
   GlobalDeclMapType::const_iterator I = GlobalDeclMap.find(GlobalID);
   assert(I != GlobalDeclMap.end() && "Corrupted global declaration map");
   ModuleFile *Owner = I->second;
@@ -6487,18 +6699,18 @@ DeclID ASTReader::mapGlobalIDToModuleFileGlobalID(ModuleFile &M,
     = M.GlobalToLocalDeclIDs.find(Owner);
   if (Pos == M.GlobalToLocalDeclIDs.end())
     return 0;
-      
+
   return GlobalID - Owner->BaseDeclID + Pos->second;
 }
 
-serialization::DeclID ASTReader::ReadDeclID(ModuleFile &F, 
+serialization::DeclID ASTReader::ReadDeclID(ModuleFile &F,
                                             const RecordData &Record,
                                             unsigned &Idx) {
   if (Idx >= Record.size()) {
     Error("Corrupted AST file");
     return 0;
   }
-  
+
   return getGlobalDeclID(F, Record[Idx++]);
 }
 
@@ -6591,7 +6803,7 @@ public:
   }
 };
 
-}
+} // end anonymous namespace
 
 void ASTReader::FindFileRegionDecls(FileID File,
                                     unsigned Offset, unsigned Length,
@@ -6630,7 +6842,7 @@ void ASTReader::FindFileRegionDecls(FileID File,
                              EndLoc, DIDComp);
   if (EndIt != DInfo.Decls.end())
     ++EndIt;
-  
+
   for (ArrayRef<serialization::LocalDeclID>::iterator
          DIt = BeginIt; DIt != EndIt; ++DIt)
     Decls.push_back(GetDecl(getGlobalDeclID(*DInfo.Mod, *DIt)));
@@ -6841,23 +7053,23 @@ void ASTReader::PrintStats() {
     std::fprintf(stderr, "\n");
     GlobalIndex->printStats();
   }
-  
+
   std::fprintf(stderr, "\n");
   dump();
   std::fprintf(stderr, "\n");
 }
 
 template<typename Key, typename ModuleFile, unsigned InitialCapacity>
-static void 
+static void
 dumpModuleIDMap(StringRef Name,
-                const ContinuousRangeMap<Key, ModuleFile *, 
+                const ContinuousRangeMap<Key, ModuleFile *,
                                          InitialCapacity> &Map) {
   if (Map.begin() == Map.end())
     return;
-  
+
   typedef ContinuousRangeMap<Key, ModuleFile *, InitialCapacity> MapType;
   llvm::errs() << Name << ":\n";
-  for (typename MapType::const_iterator I = Map.begin(), IEnd = Map.end(); 
+  for (typename MapType::const_iterator I = Map.begin(), IEnd = Map.end();
        I != IEnd; ++I) {
     llvm::errs() << "  " << I->first << " -> " << I->second->FileName
       << "\n";
@@ -6874,11 +7086,11 @@ LLVM_DUMP_METHOD void ASTReader::dump() {
   dumpModuleIDMap("Global macro map", GlobalMacroMap);
   dumpModuleIDMap("Global submodule map", GlobalSubmoduleMap);
   dumpModuleIDMap("Global selector map", GlobalSelectorMap);
-  dumpModuleIDMap("Global preprocessed entity map", 
+  dumpModuleIDMap("Global preprocessed entity map",
                   GlobalPreprocessedEntityMap);
-  
+
   llvm::errs() << "\n*** PCH/Modules Loaded:";
-  for (ModuleManager::ModuleConstIterator M = ModuleMgr.begin(), 
+  for (ModuleManager::ModuleConstIterator M = ModuleMgr.begin(),
                                        MEnd = ModuleMgr.end();
        M != MEnd; ++M)
     (*M)->dump();
@@ -6921,14 +7133,9 @@ void ASTReader::InitializeSema(Sema &S) {
     SemaObj->FPFeatures.fp_contract = FPPragmaOptions[0];
   }
 
-  // FIXME: What happens if these are changed by a module import?
-  if (!OpenCLExtensions.empty()) {
-    unsigned I = 0;
-#define OPENCLEXT(nm)  SemaObj->OpenCLFeatures.nm = OpenCLExtensions[I++];
-#include "clang/Basic/OpenCLExtensions.def"
-
-    assert(OpenCLExtensions.size() == I && "Wrong number of OPENCL_EXTENSIONS");
-  }
+  SemaObj->OpenCLFeatures.copy(OpenCLExtensions);
+  SemaObj->OpenCLTypeExtMap = OpenCLTypeExtMap;
+  SemaObj->OpenCLDeclExtMap = OpenCLDeclExtMap;
 
   UpdateSema();
 }
@@ -6939,12 +7146,14 @@ void ASTReader::UpdateSema() {
   // Load the offsets of the declarations that Sema references.
   // They will be lazily deserialized when needed.
   if (!SemaDeclRefs.empty()) {
-    assert(SemaDeclRefs.size() % 2 == 0);
-    for (unsigned I = 0; I != SemaDeclRefs.size(); I += 2) {
+    assert(SemaDeclRefs.size() % 3 == 0);
+    for (unsigned I = 0; I != SemaDeclRefs.size(); I += 3) {
       if (!SemaObj->StdNamespace)
         SemaObj->StdNamespace = SemaDeclRefs[I];
       if (!SemaObj->StdBadAlloc)
         SemaObj->StdBadAlloc = SemaDeclRefs[I+1];
+      if (!SemaObj->StdAlignValT)
+        SemaObj->StdAlignValT = SemaDeclRefs[I+2];
     }
     SemaDeclRefs.clear();
   }
@@ -6961,6 +7170,7 @@ void ASTReader::UpdateSema() {
             PragmaMSPointersToMembersState,
         PointersToMembersPragmaLocation);
   }
+  SemaObj->ForceCUDAHostDeviceDepth = ForceCUDAHostDeviceDepth;
 }
 
 IdentifierInfo *ASTReader::get(StringRef Name) {
@@ -6999,6 +7209,7 @@ IdentifierInfo *ASTReader::get(StringRef Name) {
 }
 
 namespace clang {
+
   /// \brief An identifier-lookup iterator that enumerates all of the
   /// identifiers stored within a set of AST files.
   class ASTIdentifierIterator : public IdentifierIterator {
@@ -7026,7 +7237,8 @@ namespace clang {
 
     StringRef Next() override;
   };
-}
+
+} // end namespace clang
 
 ASTIdentifierIterator::ASTIdentifierIterator(const ASTReader &Reader,
                                              bool SkipModules)
@@ -7058,6 +7270,7 @@ StringRef ASTIdentifierIterator::Next() {
 }
 
 namespace {
+
 /// A utility for appending two IdentifierIterators.
 class ChainedIdentifierIterator : public IdentifierIterator {
   std::unique_ptr<IdentifierIterator> Current;
@@ -7082,6 +7295,7 @@ public:
     return Next();
   }
 };
+
 } // end anonymous namespace.
 
 IdentifierIterator *ASTReader::getIdentifiers() {
@@ -7097,7 +7311,9 @@ IdentifierIterator *ASTReader::getIdentifiers() {
   return new ASTIdentifierIterator(*this);
 }
 
-namespace clang { namespace serialization {
+namespace clang {
+namespace serialization {
+
   class ReadMethodPoolVisitor {
     ASTReader &Reader;
     Selector Sel;
@@ -7119,7 +7335,7 @@ namespace clang { namespace serialization {
     bool operator()(ModuleFile &M) {
       if (!M.SelectorLookupTable)
         return false;
-      
+
       // If we've already searched this module file, skip it now.
       if (M.Generation <= PriorGeneration)
         return true;
@@ -7149,14 +7365,14 @@ namespace clang { namespace serialization {
       FactoryHasMoreThanOneDecl = Data.FactoryHasMoreThanOneDecl;
       return true;
     }
-    
+
     /// \brief Retrieve the instance methods found by this visitor.
-    ArrayRef<ObjCMethodDecl *> getInstanceMethods() const { 
-      return InstanceMethods; 
+    ArrayRef<ObjCMethodDecl *> getInstanceMethods() const {
+      return InstanceMethods;
     }
 
     /// \brief Retrieve the instance methods found by this visitor.
-    ArrayRef<ObjCMethodDecl *> getFactoryMethods() const { 
+    ArrayRef<ObjCMethodDecl *> getFactoryMethods() const {
       return FactoryMethods;
     }
 
@@ -7167,7 +7383,9 @@ namespace clang { namespace serialization {
     }
     bool factoryHasMoreThanOneDecl() const { return FactoryHasMoreThanOneDecl; }
   };
-} } // end namespace clang::serialization
+
+} // end namespace serialization
+} // end namespace clang
 
 /// \brief Add the given set of methods to the method list.
 static void addMethodsToPool(Sema &S, ArrayRef<ObjCMethodDecl *> Methods,
@@ -7176,14 +7394,14 @@ static void addMethodsToPool(Sema &S, ArrayRef<ObjCMethodDecl *> Methods,
     S.addMethodToGlobalList(&List, Methods[I]);
   }
 }
-                             
+
 void ASTReader::ReadMethodPool(Selector Sel) {
   // Get the selector generation and update it to the current generation.
   unsigned &Generation = SelectorGeneration[Sel];
   unsigned PriorGeneration = Generation;
   Generation = getGeneration();
   SelectorOutOfDate[Sel] = false;
-  
+
   // Search for methods defined with this selector.
   ++NumMethodPoolLookups;
   ReadMethodPoolVisitor Visitor(*this, Sel, PriorGeneration);
@@ -7197,7 +7415,7 @@ void ASTReader::ReadMethodPool(Selector Sel) {
 
   if (!getSema())
     return;
-  
+
   Sema &S = *getSema();
   Sema::GlobalMethodPool::iterator Pos
     = S.MethodPool.insert(std::make_pair(Sel, Sema::GlobalMethods())).first;
@@ -7222,9 +7440,9 @@ void ASTReader::updateOutOfDateSelector(Selector Sel) {
 void ASTReader::ReadKnownNamespaces(
                           SmallVectorImpl<NamespaceDecl *> &Namespaces) {
   Namespaces.clear();
-  
+
   for (unsigned I = 0, N = KnownNamespaces.size(); I != N; ++I) {
-    if (NamespaceDecl *Namespace 
+    if (NamespaceDecl *Namespace
                 = dyn_cast_or_null<NamespaceDecl>(GetDecl(KnownNamespaces[I])))
       Namespaces.push_back(Namespace);
   }
@@ -7313,7 +7531,7 @@ void ASTReader::ReadReferencedSelectors(
        SmallVectorImpl<std::pair<Selector, SourceLocation> > &Sels) {
   if (ReferencedSelectorsData.empty())
     return;
-  
+
   // If there are @selector references added them to its pool. This is for
   // implementation of -Wselector.
   unsigned int DataSize = ReferencedSelectorsData.size()-1;
@@ -7333,9 +7551,9 @@ void ASTReader::ReadWeakUndeclaredIdentifiers(
     return;
 
   for (unsigned I = 0, N = WeakUndeclaredIdentifiers.size(); I < N; /*none*/) {
-    IdentifierInfo *WeakId 
+    IdentifierInfo *WeakId
       = DecodeIdentifierInfo(WeakUndeclaredIdentifiers[I++]);
-    IdentifierInfo *AliasId 
+    IdentifierInfo *AliasId
       = DecodeIdentifierInfo(WeakUndeclaredIdentifiers[I++]);
     SourceLocation Loc
       = SourceLocation::getFromRawEncoding(WeakUndeclaredIdentifiers[I++]);
@@ -7355,7 +7573,7 @@ void ASTReader::ReadUsedVTables(SmallVectorImpl<ExternalVTableUse> &VTables) {
     VT.DefinitionRequired = VTableUses[Idx++];
     VTables.push_back(VT);
   }
-  
+
   VTableUses.clear();
 }
 
@@ -7367,17 +7585,18 @@ void ASTReader::ReadPendingInstantiations(
       = SourceLocation::getFromRawEncoding(PendingInstantiations[Idx++]);
 
     Pending.push_back(std::make_pair(D, Loc));
-  }  
+  }
   PendingInstantiations.clear();
 }
 
 void ASTReader::ReadLateParsedTemplates(
-    llvm::MapVector<const FunctionDecl *, LateParsedTemplate *> &LPTMap) {
+    llvm::MapVector<const FunctionDecl *, std::unique_ptr<LateParsedTemplate>>
+        &LPTMap) {
   for (unsigned Idx = 0, N = LateParsedTemplates.size(); Idx < N;
        /* In loop */) {
     FunctionDecl *FD = cast<FunctionDecl>(GetDecl(LateParsedTemplates[Idx++]));
 
-    LateParsedTemplate *LT = new LateParsedTemplate;
+    auto LT = llvm::make_unique<LateParsedTemplate>();
     LT->D = GetDecl(LateParsedTemplates[Idx++]);
 
     ModuleFile *F = getOwningModuleFile(LT->D);
@@ -7388,7 +7607,7 @@ void ASTReader::ReadLateParsedTemplates(
     for (unsigned T = 0; T < TokN; ++T)
       LT->Toks.push_back(ReadToken(*F, LateParsedTemplates, Idx));
 
-    LPTMap.insert(std::make_pair(FD, LT));
+    LPTMap.insert(std::make_pair(FD, std::move(LT)));
   }
 
   LateParsedTemplates.clear();
@@ -7498,12 +7717,12 @@ IdentifierInfo *ASTReader::getLocalIdentifier(ModuleFile &M, unsigned LocalID) {
 IdentifierID ASTReader::getGlobalIdentifierID(ModuleFile &M, unsigned LocalID) {
   if (LocalID < NUM_PREDEF_IDENT_IDS)
     return LocalID;
-  
+
   ContinuousRangeMap<uint32_t, int, 2>::iterator I
     = M.IdentifierRemap.find(LocalID - NUM_PREDEF_IDENT_IDS);
-  assert(I != M.IdentifierRemap.end() 
+  assert(I != M.IdentifierRemap.end()
          && "Invalid index into identifier index remap");
-  
+
   return LocalID + I->second;
 }
 
@@ -7524,7 +7743,7 @@ MacroInfo *ASTReader::getMacro(MacroID ID) {
     ModuleFile *M = I->second;
     unsigned Index = ID - M->BaseMacroID;
     MacrosLoaded[ID] = ReadMacroRecord(*M, M->MacroOffsets[Index]);
-    
+
     if (DeserializationListener)
       DeserializationListener->MacroRead(ID + NUM_PREDEF_MACRO_IDS,
                                          MacrosLoaded[ID]);
@@ -7548,12 +7767,12 @@ serialization::SubmoduleID
 ASTReader::getGlobalSubmoduleID(ModuleFile &M, unsigned LocalID) {
   if (LocalID < NUM_PREDEF_SUBMODULE_IDS)
     return LocalID;
-  
+
   ContinuousRangeMap<uint32_t, int, 2>::iterator I
     = M.SubmoduleRemap.find(LocalID - NUM_PREDEF_SUBMODULE_IDS);
-  assert(I != M.SubmoduleRemap.end() 
+  assert(I != M.SubmoduleRemap.end()
          && "Invalid index into submodule index remap");
-  
+
   return LocalID + I->second;
 }
 
@@ -7562,12 +7781,12 @@ Module *ASTReader::getSubmodule(SubmoduleID GlobalID) {
     assert(GlobalID == 0 && "Unhandled global submodule ID");
     return nullptr;
   }
-  
+
   if (GlobalID > SubmodulesLoaded.size()) {
     Error("submodule ID out of range in AST file");
     return nullptr;
   }
-  
+
   return SubmodulesLoaded[GlobalID - NUM_PREDEF_SUBMODULE_IDS];
 }
 
@@ -7664,17 +7883,17 @@ serialization::SelectorID
 ASTReader::getGlobalSelectorID(ModuleFile &M, unsigned LocalID) const {
   if (LocalID < NUM_PREDEF_SELECTOR_IDS)
     return LocalID;
-  
+
   ContinuousRangeMap<uint32_t, int, 2>::iterator I
     = M.SelectorRemap.find(LocalID - NUM_PREDEF_SELECTOR_IDS);
-  assert(I != M.SelectorRemap.end() 
+  assert(I != M.SelectorRemap.end()
          && "Invalid index into selector index remap");
-  
+
   return LocalID + I->second;
 }
 
 DeclarationName
-ASTReader::ReadDeclarationName(ModuleFile &F, 
+ASTReader::ReadDeclarationName(ModuleFile &F,
                                const RecordData &Record, unsigned &Idx) {
   DeclarationName::NameKind Kind = (DeclarationName::NameKind)Record[Idx++];
   switch (Kind) {
@@ -7762,13 +7981,13 @@ void ASTReader::ReadQualifierInfo(ModuleFile &F, QualifierInfo &Info,
   Info.NumTemplParamLists = NumTPLists;
   if (NumTPLists) {
     Info.TemplParamLists = new (Context) TemplateParameterList*[NumTPLists];
-    for (unsigned i=0; i != NumTPLists; ++i)
+    for (unsigned i = 0; i != NumTPLists; ++i)
       Info.TemplParamLists[i] = ReadTemplateParameterList(F, Record, Idx);
   }
 }
 
 TemplateName
-ASTReader::ReadTemplateName(ModuleFile &F, const RecordData &Record, 
+ASTReader::ReadTemplateName(ModuleFile &F, const RecordData &Record,
                             unsigned &Idx) {
   TemplateName::NameKind Kind = (TemplateName::NameKind)Record[Idx++];
   switch (Kind) {
@@ -7795,7 +8014,7 @@ ASTReader::ReadTemplateName(ModuleFile &F, const RecordData &Record,
     NestedNameSpecifier *NNS = ReadNestedNameSpecifier(F, Record, Idx);
     if (Record[Idx++])  // isIdentifier
       return Context.getDependentTemplateName(NNS,
-                                               GetIdentifierInfo(F, Record, 
+                                               GetIdentifierInfo(F, Record,
                                                                  Idx));
     return Context.getDependentTemplateName(NNS,
                                          (OverloadedOperatorKind)Record[Idx++]);
@@ -7808,17 +8027,17 @@ ASTReader::ReadTemplateName(ModuleFile &F, const RecordData &Record,
     TemplateName replacement = ReadTemplateName(F, Record, Idx);
     return Context.getSubstTemplateTemplateParm(param, replacement);
   }
-      
+
   case TemplateName::SubstTemplateTemplateParmPack: {
-    TemplateTemplateParmDecl *Param 
+    TemplateTemplateParmDecl *Param
       = ReadDeclAs<TemplateTemplateParmDecl>(F, Record, Idx);
     if (!Param)
       return TemplateName();
-    
+
     TemplateArgument ArgPack = ReadTemplateArgument(F, Record, Idx);
     if (ArgPack.getKind() != TemplateArgument::Pack)
       return TemplateName();
-    
+
     return Context.getSubstTemplateTemplateParmPack(Param, ArgPack);
   }
   }
@@ -7856,7 +8075,7 @@ TemplateArgument ASTReader::ReadTemplateArgument(ModuleFile &F,
     QualType T = readType(F, Record, Idx);
     return TemplateArgument(Context, Value, T);
   }
-  case TemplateArgument::Template: 
+  case TemplateArgument::Template:
     return TemplateArgument(ReadTemplateName(F, Record, Idx));
   case TemplateArgument::TemplateExpansion: {
     TemplateName Name = ReadTemplateName(F, Record, Idx);
@@ -7892,9 +8111,10 @@ ASTReader::ReadTemplateParameterList(ModuleFile &F,
   while (NumParams--)
     Params.push_back(ReadDeclAs<NamedDecl>(F, Record, Idx));
 
+  // TODO: Concepts
   TemplateParameterList* TemplateParams =
     TemplateParameterList::Create(Context, TemplateLoc, LAngleLoc,
-                                  Params, RAngleLoc);
+                                  Params, RAngleLoc, nullptr);
   return TemplateParams;
 }
 
@@ -7931,7 +8151,7 @@ ASTReader::ReadCXXBaseSpecifier(ModuleFile &F,
   TypeSourceInfo *TInfo = GetTypeSourceInfo(F, Record, Idx);
   SourceRange Range = ReadSourceRange(F, Record, Idx);
   SourceLocation EllipsisLoc = ReadSourceLocation(F, Record, Idx);
-  CXXBaseSpecifier Result(Range, isVirtual, isBaseOfClass, AS, TInfo, 
+  CXXBaseSpecifier Result(Range, isVirtual, isBaseOfClass, AS, TInfo,
                           EllipsisLoc);
   Result.setInheritConstructors(inheritConstructors);
   return Result;
@@ -7973,49 +8193,29 @@ ASTReader::ReadCXXCtorInitializers(ModuleFile &F, const RecordData &Record,
     Expr *Init = ReadExpr(F);
     SourceLocation LParenLoc = ReadSourceLocation(F, Record, Idx);
     SourceLocation RParenLoc = ReadSourceLocation(F, Record, Idx);
-    bool IsWritten = Record[Idx++];
-    unsigned SourceOrderOrNumArrayIndices;
-    SmallVector<VarDecl *, 8> Indices;
-    if (IsWritten) {
-      SourceOrderOrNumArrayIndices = Record[Idx++];
-    } else {
-      SourceOrderOrNumArrayIndices = Record[Idx++];
-      Indices.reserve(SourceOrderOrNumArrayIndices);
-      for (unsigned i=0; i != SourceOrderOrNumArrayIndices; ++i)
-        Indices.push_back(ReadDeclAs<VarDecl>(F, Record, Idx));
-    }
 
     CXXCtorInitializer *BOMInit;
-    if (Type == CTOR_INITIALIZER_BASE) {
+    if (Type == CTOR_INITIALIZER_BASE)
       BOMInit = new (Context)
           CXXCtorInitializer(Context, TInfo, IsBaseVirtual, LParenLoc, Init,
                              RParenLoc, MemberOrEllipsisLoc);
-    } else if (Type == CTOR_INITIALIZER_DELEGATING) {
+    else if (Type == CTOR_INITIALIZER_DELEGATING)
       BOMInit = new (Context)
           CXXCtorInitializer(Context, TInfo, LParenLoc, Init, RParenLoc);
-    } else if (IsWritten) {
-      if (Member)
-        BOMInit = new (Context) CXXCtorInitializer(
-            Context, Member, MemberOrEllipsisLoc, LParenLoc, Init, RParenLoc);
-      else
-        BOMInit = new (Context)
-            CXXCtorInitializer(Context, IndirectMember, MemberOrEllipsisLoc,
-                               LParenLoc, Init, RParenLoc);
-    } else {
-      if (IndirectMember) {
-        assert(Indices.empty() && "Indirect field improperly initialized");
-        BOMInit = new (Context)
-            CXXCtorInitializer(Context, IndirectMember, MemberOrEllipsisLoc,
-                               LParenLoc, Init, RParenLoc);
-      } else {
-        BOMInit = CXXCtorInitializer::Create(
-            Context, Member, MemberOrEllipsisLoc, LParenLoc, Init, RParenLoc,
-            Indices.data(), Indices.size());
-      }
+    else if (Member)
+      BOMInit = new (Context)
+          CXXCtorInitializer(Context, Member, MemberOrEllipsisLoc, LParenLoc,
+                             Init, RParenLoc);
+    else
+      BOMInit = new (Context)
+          CXXCtorInitializer(Context, IndirectMember, MemberOrEllipsisLoc,
+                             LParenLoc, Init, RParenLoc);
+
+    if (/*IsWritten*/Record[Idx++]) {
+      unsigned SourceOrder = Record[Idx++];
+      BOMInit->setSourceOrder(SourceOrder);
     }
 
-    if (IsWritten)
-      BOMInit->setSourceOrder(SourceOrderOrNumArrayIndices);
     CtorInitializers[i] = BOMInit;
   }
 
@@ -8078,7 +8278,7 @@ ASTReader::ReadNestedNameSpecifier(ModuleFile &F,
 }
 
 NestedNameSpecifierLoc
-ASTReader::ReadNestedNameSpecifierLoc(ModuleFile &F, const RecordData &Record, 
+ASTReader::ReadNestedNameSpecifierLoc(ModuleFile &F, const RecordData &Record,
                                       unsigned &Idx) {
   unsigned N = Record[Idx++];
   NestedNameSpecifierLocBuilder Builder;
@@ -8087,7 +8287,7 @@ ASTReader::ReadNestedNameSpecifierLoc(ModuleFile &F, const RecordData &Record,
       = (NestedNameSpecifier::SpecifierKind)Record[Idx++];
     switch (Kind) {
     case NestedNameSpecifier::Identifier: {
-      IdentifierInfo *II = GetIdentifierInfo(F, Record, Idx);      
+      IdentifierInfo *II = GetIdentifierInfo(F, Record, Idx);
       SourceRange Range = ReadSourceRange(F, Record, Idx);
       Builder.Extend(Context, II, Range.getBegin(), Range.getEnd());
       break;
@@ -8116,7 +8316,7 @@ ASTReader::ReadNestedNameSpecifierLoc(ModuleFile &F, const RecordData &Record,
       SourceLocation ColonColonLoc = ReadSourceLocation(F, Record, Idx);
 
       // FIXME: 'template' keyword location not saved anywhere, so we fake it.
-      Builder.Extend(Context, 
+      Builder.Extend(Context,
                      Template? T->getTypeLoc().getBeginLoc() : SourceLocation(),
                      T->getTypeLoc(), ColonColonLoc);
       break;
@@ -8185,7 +8385,7 @@ std::string ASTReader::ReadPath(ModuleFile &F, const RecordData &Record,
   return Filename;
 }
 
-VersionTuple ASTReader::ReadVersionTuple(const RecordData &Record, 
+VersionTuple ASTReader::ReadVersionTuple(const RecordData &Record,
                                          unsigned &Idx) {
   unsigned Major = Record[Idx++];
   unsigned Minor = Record[Idx++];
@@ -8197,7 +8397,7 @@ VersionTuple ASTReader::ReadVersionTuple(const RecordData &Record,
   return VersionTuple(Major, Minor - 1, Subminor - 1);
 }
 
-CXXTemporary *ASTReader::ReadCXXTemporary(ModuleFile &F, 
+CXXTemporary *ASTReader::ReadCXXTemporary(ModuleFile &F,
                                           const RecordData &Record,
                                           unsigned &Idx) {
   CXXDestructorDecl *Decl = ReadDeclAs<CXXDestructorDecl>(F, Record, Idx);
@@ -8283,6 +8483,10 @@ void ASTReader::ReadComments() {
       }
     }
   NextCursor:
+    // De-serialized SourceLocations get negative FileIDs for other modules,
+    // potentially invalidating the original order. Sort it again.
+    std::sort(Comments.begin(), Comments.end(),
+              BeforeThanCompare<RawComment>(SourceMgr));
     Context.Comments.addDeserializedComments(Comments);
   }
 }
@@ -8350,16 +8554,14 @@ void ASTReader::finishPendingActions() {
       for (unsigned IDIdx = 0, NumIDs = GlobalIDs.size(); IDIdx != NumIDs;
            ++IDIdx) {
         const PendingMacroInfo &Info = GlobalIDs[IDIdx];
-        if (Info.M->Kind != MK_ImplicitModule &&
-            Info.M->Kind != MK_ExplicitModule)
+        if (!Info.M->isModule())
           resolvePendingMacro(II, Info);
       }
       // Handle module imports.
       for (unsigned IDIdx = 0, NumIDs = GlobalIDs.size(); IDIdx != NumIDs;
            ++IDIdx) {
         const PendingMacroInfo &Info = GlobalIDs[IDIdx];
-        if (Info.M->Kind == MK_ImplicitModule ||
-            Info.M->Kind == MK_ExplicitModule)
+        if (Info.M->isModule())
           resolvePendingMacro(II, Info);
       }
     }
@@ -8390,7 +8592,7 @@ void ASTReader::finishPendingActions() {
 
   // If we deserialized any C++ or Objective-C class definitions, any
   // Objective-C protocol definitions, or any redeclarable templates, make sure
-  // that all redeclarations point to the definitions. Note that this can only 
+  // that all redeclarations point to the definitions. Note that this can only
   // happen now, after the redeclaration chains have been fully wired.
   for (Decl *D : PendingDefinitions) {
     if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
@@ -8446,8 +8648,11 @@ void ASTReader::finishPendingActions() {
     if (FunctionDecl *FD = dyn_cast<FunctionDecl>(PB->first)) {
       // FIXME: Check for =delete/=default?
       // FIXME: Complain about ODR violations here?
-      if (!getContext().getLangOpts().Modules || !FD->hasBody())
+      const FunctionDecl *Defn = nullptr;
+      if (!getContext().getLangOpts().Modules || !FD->hasBody(Defn))
         FD->setLazyBody(PB->second);
+      else
+        mergeDefinitionVisibility(const_cast<FunctionDecl*>(Defn), FD);
       continue;
     }
 
@@ -8542,7 +8747,7 @@ void ASTReader::diagnoseOdrViolations() {
       // completed. We only really need to mark FieldDecls as invalid here.
       if (!isa<TagDecl>(D))
         D->setInvalidDecl();
-      
+
       // Ensure we don't accidentally recursively enter deserialization while
       // we're producing our diagnostic.
       Deserializing RecursionGuard(this);
@@ -8617,7 +8822,7 @@ void ASTReader::diagnoseOdrViolations() {
 }
 
 void ASTReader::StartedDeserializing() {
-  if (++NumCurrentElementsDeserializing == 1 && ReadTimer.get()) 
+  if (++NumCurrentElementsDeserializing == 1 && ReadTimer.get())
     ReadTimer->startTimer();
 }
 
@@ -8694,7 +8899,10 @@ ASTReader::ASTReader(
   bool AllowConfigurationMismatch, bool ValidateSystemInputs,
   bool UseGlobalIndex,
   std::unique_ptr<llvm::Timer> ReadTimer)
-    : Listener(new PCHValidator(PP, *this)), DeserializationListener(nullptr),
+    : Listener(DisableValidation ?
+        cast<ASTReaderListener>(new SimpleASTReaderListener(PP)) :
+        cast<ASTReaderListener>(new PCHValidator(PP, *this))),
+      DeserializationListener(nullptr),
       OwnsDeserializationListener(false), SourceMgr(PP.getSourceManager()),
       FileMgr(PP.getFileManager()), PCHContainerRdr(PCHContainerRdr),
       Diags(PP.getDiagnostics()), SemaObj(nullptr), PP(PP), Context(Context),
@@ -8743,3 +8951,10 @@ ASTReader::~ASTReader() {
 IdentifierResolver &ASTReader::getIdResolver() {
   return SemaObj ? SemaObj->IdResolver : DummyIdResolver;
 }
+
+unsigned ASTRecordReader::readRecord(llvm::BitstreamCursor &Cursor,
+                                     unsigned AbbrevID) {
+  Idx = 0;
+  Record.clear();
+  return Cursor.readRecord(AbbrevID, Record);
+}
diff --git a/lib/Serialization/ASTReaderDecl.cpp b/lib/Serialization/ASTReaderDecl.cpp
index 35da8f3ebcfe..6e18b208a9ae 100644
--- a/lib/Serialization/ASTReaderDecl.cpp
+++ b/lib/Serialization/ASTReaderDecl.cpp
@@ -12,10 +12,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "clang/Serialization/ASTReader.h"
 #include "ASTCommon.h"
 #include "ASTReaderInternals.h"
-#include "clang/AST/ASTConsumer.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/DeclCXX.h"
 #include "clang/AST/DeclGroup.h"
@@ -24,6 +22,7 @@
 #include "clang/AST/Expr.h"
 #include "clang/Sema/IdentifierResolver.h"
 #include "clang/Sema/SemaDiagnostic.h"
+#include "clang/Serialization/ASTReader.h"
 #include "llvm/Support/SaveAndRestore.h"
 
 using namespace clang;
@@ -36,13 +35,11 @@ using namespace clang::serialization;
 namespace clang {
   class ASTDeclReader : public DeclVisitor<ASTDeclReader, void> {
     ASTReader &Reader;
-    ModuleFile &F;
-    uint64_t Offset;
+    ASTRecordReader &Record;
+    ASTReader::RecordLocation Loc;
     const DeclID ThisDeclID;
     const SourceLocation ThisDeclLoc;
     typedef ASTReader::RecordData RecordData;
-    const RecordData &Record;
-    unsigned &Idx;
     TypeID TypeIDForTypeDecl;
     unsigned AnonymousDeclNumber;
     GlobalDeclID NamedDeclForTagDecl;
@@ -57,83 +54,77 @@ namespace clang {
 
     uint64_t GetCurrentCursorOffset();
 
-    uint64_t ReadLocalOffset(const RecordData &R, unsigned &I) {
-      uint64_t LocalOffset = R[I++];
-      assert(LocalOffset < Offset && "offset point after current record");
-      return LocalOffset ? Offset - LocalOffset : 0;
+    uint64_t ReadLocalOffset() {
+      uint64_t LocalOffset = Record.readInt();
+      assert(LocalOffset < Loc.Offset && "offset point after current record");
+      return LocalOffset ? Loc.Offset - LocalOffset : 0;
     }
 
-    uint64_t ReadGlobalOffset(ModuleFile &F, const RecordData &R, unsigned &I) {
-      uint64_t Local = ReadLocalOffset(R, I);
-      return Local ? Reader.getGlobalBitOffset(F, Local) : 0;
+    uint64_t ReadGlobalOffset() {
+      uint64_t Local = ReadLocalOffset();
+      return Local ? Record.getGlobalBitOffset(Local) : 0;
     }
 
-    SourceLocation ReadSourceLocation(const RecordData &R, unsigned &I) {
-      return Reader.ReadSourceLocation(F, R, I);
+    SourceLocation ReadSourceLocation() {
+      return Record.readSourceLocation();
     }
 
-    SourceRange ReadSourceRange(const RecordData &R, unsigned &I) {
-      return Reader.ReadSourceRange(F, R, I);
+    SourceRange ReadSourceRange() {
+      return Record.readSourceRange();
     }
 
-    TypeSourceInfo *GetTypeSourceInfo(const RecordData &R, unsigned &I) {
-      return Reader.GetTypeSourceInfo(F, R, I);
+    TypeSourceInfo *GetTypeSourceInfo() {
+      return Record.getTypeSourceInfo();
     }
 
-    serialization::DeclID ReadDeclID(const RecordData &R, unsigned &I) {
-      return Reader.ReadDeclID(F, R, I);
+    serialization::DeclID ReadDeclID() {
+      return Record.readDeclID();
     }
 
-    std::string ReadString(const RecordData &R, unsigned &I) {
-      return Reader.ReadString(R, I);
+    std::string ReadString() {
+      return Record.readString();
     }
 
     void ReadDeclIDList(SmallVectorImpl<DeclID> &IDs) {
-      for (unsigned I = 0, Size = Record[Idx++]; I != Size; ++I)
-        IDs.push_back(ReadDeclID(Record, Idx));
+      for (unsigned I = 0, Size = Record.readInt(); I != Size; ++I)
+        IDs.push_back(ReadDeclID());
     }
 
-    Decl *ReadDecl(const RecordData &R, unsigned &I) {
-      return Reader.ReadDecl(F, R, I);
+    Decl *ReadDecl() {
+      return Record.readDecl();
     }
 
     template<typename T>
-    T *ReadDeclAs(const RecordData &R, unsigned &I) {
-      return Reader.ReadDeclAs<T>(F, R, I);
+    T *ReadDeclAs() {
+      return Record.readDeclAs<T>();
     }
 
-    void ReadQualifierInfo(QualifierInfo &Info,
-                           const RecordData &R, unsigned &I) {
-      Reader.ReadQualifierInfo(F, Info, R, I);
-    }
-    
-    void ReadDeclarationNameLoc(DeclarationNameLoc &DNLoc, DeclarationName Name,
-                                const RecordData &R, unsigned &I) {
-      Reader.ReadDeclarationNameLoc(F, DNLoc, Name, R, I);
+    void ReadQualifierInfo(QualifierInfo &Info) {
+      Record.readQualifierInfo(Info);
     }
-    
-    void ReadDeclarationNameInfo(DeclarationNameInfo &NameInfo,
-                                const RecordData &R, unsigned &I) {
-      Reader.ReadDeclarationNameInfo(F, NameInfo, R, I);
+
+    void ReadDeclarationNameLoc(DeclarationNameLoc &DNLoc, DeclarationName Name) {
+      Record.readDeclarationNameLoc(DNLoc, Name);
     }
 
-    serialization::SubmoduleID readSubmoduleID(const RecordData &R, 
-                                               unsigned &I) {
-      if (I >= R.size())
+    serialization::SubmoduleID readSubmoduleID() {
+      if (Record.getIdx() == Record.size())
         return 0;
-      
-      return Reader.getGlobalSubmoduleID(F, R[I++]);
+
+      return Record.getGlobalSubmoduleID(Record.readInt());
     }
-    
-    Module *readModule(const RecordData &R, unsigned &I) {
-      return Reader.getSubmodule(readSubmoduleID(R, I));
+
+    Module *readModule() {
+      return Record.getSubmodule(readSubmoduleID());
     }
 
     void ReadCXXRecordDefinition(CXXRecordDecl *D, bool Update);
-    void ReadCXXDefinitionData(struct CXXRecordDecl::DefinitionData &Data,
-                               const RecordData &R, unsigned &I);
+    void ReadCXXDefinitionData(struct CXXRecordDecl::DefinitionData &Data);
     void MergeDefinitionData(CXXRecordDecl *D,
                              struct CXXRecordDecl::DefinitionData &&NewDD);
+    void ReadObjCDefinitionData(struct ObjCInterfaceDecl::DefinitionData &Data);
+    void MergeDefinitionData(ObjCInterfaceDecl *D,
+                             struct ObjCInterfaceDecl::DefinitionData &&NewDD);
 
     static NamedDecl *getAnonymousDeclForMerging(ASTReader &Reader,
                                                  DeclContext *DC,
@@ -143,13 +134,13 @@ namespace clang {
 
     /// Results from loading a RedeclarableDecl.
     class RedeclarableResult {
-      GlobalDeclID FirstID;
       Decl *MergeWith;
+      GlobalDeclID FirstID;
       bool IsKeyDecl;
 
     public:
-      RedeclarableResult(GlobalDeclID FirstID, Decl *MergeWith, bool IsKeyDecl)
-          : FirstID(FirstID), MergeWith(MergeWith), IsKeyDecl(IsKeyDecl) {}
+      RedeclarableResult(Decl *MergeWith, GlobalDeclID FirstID, bool IsKeyDecl)
+        : MergeWith(MergeWith), FirstID(FirstID), IsKeyDecl(IsKeyDecl) {}
 
       /// \brief Retrieve the first ID.
       GlobalDeclID getFirstID() const { return FirstID; }
@@ -171,12 +162,12 @@ namespace clang {
       ASTReader &Reader;
       NamedDecl *New;
       NamedDecl *Existing;
-      mutable bool AddResult;
+      bool AddResult;
 
       unsigned AnonymousDeclNumber;
       IdentifierInfo *TypedefNameForLinkage;
 
-      void operator=(FindExistingResult&) = delete;
+      void operator=(FindExistingResult &&) = delete;
 
     public:
       FindExistingResult(ASTReader &Reader)
@@ -190,7 +181,7 @@ namespace clang {
             AnonymousDeclNumber(AnonymousDeclNumber),
             TypedefNameForLinkage(TypedefNameForLinkage) {}
 
-      FindExistingResult(const FindExistingResult &Other)
+      FindExistingResult(FindExistingResult &&Other)
           : Reader(Other.Reader), New(Other.New), Existing(Other.Existing),
             AddResult(Other.AddResult),
             AnonymousDeclNumber(Other.AnonymousDeclNumber),
@@ -215,11 +206,11 @@ namespace clang {
     FindExistingResult findExisting(NamedDecl *D);
 
   public:
-    ASTDeclReader(ASTReader &Reader, ASTReader::RecordLocation Loc,
-                  DeclID thisDeclID, SourceLocation ThisDeclLoc,
-                  const RecordData &Record, unsigned &Idx)
-        : Reader(Reader), F(*Loc.F), Offset(Loc.Offset), ThisDeclID(thisDeclID),
-          ThisDeclLoc(ThisDeclLoc), Record(Record), Idx(Idx),
+    ASTDeclReader(ASTReader &Reader, ASTRecordReader &Record,
+                  ASTReader::RecordLocation Loc,
+                  DeclID thisDeclID, SourceLocation ThisDeclLoc)
+        : Reader(Reader), Record(Record), Loc(Loc),
+          ThisDeclID(thisDeclID), ThisDeclLoc(ThisDeclLoc),
           TypeIDForTypeDecl(0), NamedDeclForTagDecl(0),
           TypedefNameForLinkage(nullptr), HasPendingBody(false),
           IsDeclMarkedUsed(false) {}
@@ -251,8 +242,7 @@ namespace clang {
 
     void Visit(Decl *D);
 
-    void UpdateDecl(Decl *D, ModuleFile &ModuleFile,
-                    const RecordData &Record);
+    void UpdateDecl(Decl *D);
 
     static void setNextObjCCategory(ObjCCategoryDecl *Cat,
                                     ObjCCategoryDecl *Next) {
@@ -313,6 +303,8 @@ namespace clang {
     void VisitVarDecl(VarDecl *VD) { VisitVarDeclImpl(VD); }
     void VisitImplicitParamDecl(ImplicitParamDecl *PD);
     void VisitParmVarDecl(ParmVarDecl *PD);
+    void VisitDecompositionDecl(DecompositionDecl *DD);
+    void VisitBindingDecl(BindingDecl *BD);
     void VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D);
     DeclID VisitTemplateDecl(TemplateDecl *D);
     RedeclarableResult VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D);
@@ -323,9 +315,11 @@ namespace clang {
     void VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D);
     void VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D);
     void VisitUsingDecl(UsingDecl *D);
+    void VisitUsingPackDecl(UsingPackDecl *D);
     void VisitUsingShadowDecl(UsingShadowDecl *D);
     void VisitConstructorUsingShadowDecl(ConstructorUsingShadowDecl *D);
     void VisitLinkageSpecDecl(LinkageSpecDecl *D);
+    void VisitExportDecl(ExportDecl *D);
     void VisitFileScopeAsmDecl(FileScopeAsmDecl *AD);
     void VisitImportDecl(ImportDecl *D);
     void VisitAccessSpecDecl(AccessSpecDecl *D);
@@ -377,27 +371,6 @@ namespace clang {
     void VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D);
     void VisitOMPDeclareReductionDecl(OMPDeclareReductionDecl *D);
     void VisitOMPCapturedExprDecl(OMPCapturedExprDecl *D);
-
-    /// We've merged the definition \p MergedDef into the existing definition
-    /// \p Def. Ensure that \p Def is made visible whenever \p MergedDef is made
-    /// visible.
-    void mergeDefinitionVisibility(NamedDecl *Def, NamedDecl *MergedDef) {
-      if (Def->isHidden()) {
-        // If MergedDef is visible or becomes visible, make the definition visible.
-        if (!MergedDef->isHidden())
-          Def->Hidden = false;
-        else if (Reader.getContext().getLangOpts().ModulesLocalVisibility) {
-          Reader.getContext().mergeDefinitionIntoModule(
-              Def, MergedDef->getImportedOwningModule(),
-              /*NotifyListeners*/ false);
-          Reader.PendingMergedDefinitionsToDeduplicate.insert(Def);
-        } else {
-          auto SubmoduleID = MergedDef->getOwningModuleID();
-          assert(SubmoduleID && "hidden definition in no module");
-          Reader.HiddenNamesMap[Reader.getSubmodule(SubmoduleID)].push_back(Def);
-        }
-      }
-    }
   };
 } // end namespace clang
 
@@ -437,14 +410,15 @@ public:
 };
 } // end anonymous namespace
 
-template<typename DeclT>
-llvm::iterator_range<MergedRedeclIterator<DeclT>> merged_redecls(DeclT *D) {
+template <typename DeclT>
+static llvm::iterator_range<MergedRedeclIterator<DeclT>>
+merged_redecls(DeclT *D) {
   return llvm::make_range(MergedRedeclIterator<DeclT>(D),
                           MergedRedeclIterator<DeclT>());
 }
 
 uint64_t ASTDeclReader::GetCurrentCursorOffset() {
-  return F.DeclsCursor.GetCurrentBitNo() + F.GlobalBitOffset;
+  return Loc.F->DeclsCursor.GetCurrentBitNo() + Loc.F->GlobalBitOffset;
 }
 
 void ASTDeclReader::Visit(Decl *D) {
@@ -459,11 +433,10 @@ void ASTDeclReader::Visit(Decl *D) {
     if (DD->DeclInfo) {
       DeclaratorDecl::ExtInfo *Info =
           DD->DeclInfo.get<DeclaratorDecl::ExtInfo *>();
-      Info->TInfo =
-          GetTypeSourceInfo(Record, Idx);
+      Info->TInfo = GetTypeSourceInfo();
     }
     else {
-      DD->DeclInfo = GetTypeSourceInfo(Record, Idx);
+      DD->DeclInfo = GetTypeSourceInfo();
     }
   }
 
@@ -484,11 +457,11 @@ void ASTDeclReader::Visit(Decl *D) {
     // We only read it if FD doesn't already have a body (e.g., from another
     // module).
     // FIXME: Can we diagnose ODR violations somehow?
-    if (Record[Idx++]) {
+    if (Record.readInt()) {
       if (auto *CD = dyn_cast<CXXConstructorDecl>(FD)) {
-        CD->NumCtorInitializers = Record[Idx++];
+        CD->NumCtorInitializers = Record.readInt();
         if (CD->NumCtorInitializers)
-          CD->CtorInitializers = ReadGlobalOffset(F, Record, Idx);
+          CD->CtorInitializers = ReadGlobalOffset();
       }
       Reader.PendingBodies[FD] = GetCurrentCursorOffset();
       HasPendingBody = true;
@@ -505,8 +478,8 @@ void ASTDeclReader::VisitDecl(Decl *D) {
     // example, a function parameter can be used in decltype() in trailing
     // return type of the function).  Use the translation unit DeclContext as a
     // placeholder.
-    GlobalDeclID SemaDCIDForTemplateParmDecl = ReadDeclID(Record, Idx);
-    GlobalDeclID LexicalDCIDForTemplateParmDecl = ReadDeclID(Record, Idx);
+    GlobalDeclID SemaDCIDForTemplateParmDecl = ReadDeclID();
+    GlobalDeclID LexicalDCIDForTemplateParmDecl = ReadDeclID();
     if (!LexicalDCIDForTemplateParmDecl)
       LexicalDCIDForTemplateParmDecl = SemaDCIDForTemplateParmDecl;
     Reader.addPendingDeclContextInfo(D,
@@ -514,8 +487,8 @@ void ASTDeclReader::VisitDecl(Decl *D) {
                                      LexicalDCIDForTemplateParmDecl);
     D->setDeclContext(Reader.getContext().getTranslationUnitDecl()); 
   } else {
-    DeclContext *SemaDC = ReadDeclAs<DeclContext>(Record, Idx);
-    DeclContext *LexicalDC = ReadDeclAs<DeclContext>(Record, Idx);
+    DeclContext *SemaDC = ReadDeclAs<DeclContext>();
+    DeclContext *LexicalDC = ReadDeclAs<DeclContext>();
     if (!LexicalDC)
       LexicalDC = SemaDC;
     DeclContext *MergedSemaDC = Reader.MergedDeclContexts.lookup(SemaDC);
@@ -525,27 +498,27 @@ void ASTDeclReader::VisitDecl(Decl *D) {
                            Reader.getContext());
   }
   D->setLocation(ThisDeclLoc);
-  D->setInvalidDecl(Record[Idx++]);
-  if (Record[Idx++]) { // hasAttrs
+  D->setInvalidDecl(Record.readInt());
+  if (Record.readInt()) { // hasAttrs
     AttrVec Attrs;
-    Reader.ReadAttributes(F, Attrs, Record, Idx);
+    Record.readAttributes(Attrs);
     // Avoid calling setAttrs() directly because it uses Decl::getASTContext()
     // internally which is unsafe during derialization.
     D->setAttrsImpl(Attrs, Reader.getContext());
   }
-  D->setImplicit(Record[Idx++]);
-  D->Used = Record[Idx++];
+  D->setImplicit(Record.readInt());
+  D->Used = Record.readInt();
   IsDeclMarkedUsed |= D->Used;
-  D->setReferenced(Record[Idx++]);
-  D->setTopLevelDeclInObjCContainer(Record[Idx++]);
-  D->setAccess((AccessSpecifier)Record[Idx++]);
+  D->setReferenced(Record.readInt());
+  D->setTopLevelDeclInObjCContainer(Record.readInt());
+  D->setAccess((AccessSpecifier)Record.readInt());
   D->FromASTFile = true;
-  D->setModulePrivate(Record[Idx++]);
+  D->setModulePrivate(Record.readInt());
   D->Hidden = D->isModulePrivate();
 
   // Determine whether this declaration is part of a (sub)module. If so, it
   // may not yet be visible.
-  if (unsigned SubmoduleID = readSubmoduleID(Record, Idx)) {
+  if (unsigned SubmoduleID = readSubmoduleID()) {
     // Store the owning submodule ID in the declaration.
     D->setOwningModuleID(SubmoduleID);
 
@@ -571,22 +544,22 @@ void ASTDeclReader::VisitDecl(Decl *D) {
 
 void ASTDeclReader::VisitPragmaCommentDecl(PragmaCommentDecl *D) {
   VisitDecl(D);
-  D->setLocation(ReadSourceLocation(Record, Idx));
-  D->CommentKind = (PragmaMSCommentKind)Record[Idx++];
-  std::string Arg = ReadString(Record, Idx);
+  D->setLocation(ReadSourceLocation());
+  D->CommentKind = (PragmaMSCommentKind)Record.readInt();
+  std::string Arg = ReadString();
   memcpy(D->getTrailingObjects<char>(), Arg.data(), Arg.size());
   D->getTrailingObjects<char>()[Arg.size()] = '\0';
 }
 
 void ASTDeclReader::VisitPragmaDetectMismatchDecl(PragmaDetectMismatchDecl *D) {
   VisitDecl(D);
-  D->setLocation(ReadSourceLocation(Record, Idx));
-  std::string Name = ReadString(Record, Idx);
+  D->setLocation(ReadSourceLocation());
+  std::string Name = ReadString();
   memcpy(D->getTrailingObjects<char>(), Name.data(), Name.size());
   D->getTrailingObjects<char>()[Name.size()] = '\0';
 
   D->ValueStart = Name.size() + 1;
-  std::string Value = ReadString(Record, Idx);
+  std::string Value = ReadString();
   memcpy(D->getTrailingObjects<char>() + D->ValueStart, Value.data(),
          Value.size());
   D->getTrailingObjects<char>()[D->ValueStart + Value.size()] = '\0';
@@ -598,24 +571,24 @@ void ASTDeclReader::VisitTranslationUnitDecl(TranslationUnitDecl *TU) {
 
 void ASTDeclReader::VisitNamedDecl(NamedDecl *ND) {
   VisitDecl(ND);
-  ND->setDeclName(Reader.ReadDeclarationName(F, Record, Idx));
-  AnonymousDeclNumber = Record[Idx++];
+  ND->setDeclName(Record.readDeclarationName());
+  AnonymousDeclNumber = Record.readInt();
 }
 
 void ASTDeclReader::VisitTypeDecl(TypeDecl *TD) {
   VisitNamedDecl(TD);
-  TD->setLocStart(ReadSourceLocation(Record, Idx));
+  TD->setLocStart(ReadSourceLocation());
   // Delay type reading until after we have fully initialized the decl.
-  TypeIDForTypeDecl = Reader.getGlobalTypeID(F, Record[Idx++]);
+  TypeIDForTypeDecl = Record.getGlobalTypeID(Record.readInt());
 }
 
 ASTDeclReader::RedeclarableResult
 ASTDeclReader::VisitTypedefNameDecl(TypedefNameDecl *TD) {
   RedeclarableResult Redecl = VisitRedeclarable(TD);
   VisitTypeDecl(TD);
-  TypeSourceInfo *TInfo = GetTypeSourceInfo(Record, Idx);
-  if (Record[Idx++]) { // isModed
-    QualType modedT = Reader.readType(F, Record, Idx);
+  TypeSourceInfo *TInfo = GetTypeSourceInfo();
+  if (Record.readInt()) { // isModed
+    QualType modedT = Record.readType();
     TD->setModedTypeSourceInfo(TInfo, modedT);
   } else
     TD->setTypeSourceInfo(TInfo);
@@ -629,7 +602,7 @@ void ASTDeclReader::VisitTypedefDecl(TypedefDecl *TD) {
 
 void ASTDeclReader::VisitTypeAliasDecl(TypeAliasDecl *TD) {
   RedeclarableResult Redecl = VisitTypedefNameDecl(TD);
-  if (auto *Template = ReadDeclAs<TypeAliasTemplateDecl>(Record, Idx))
+  if (auto *Template = ReadDeclAs<TypeAliasTemplateDecl>())
     // Merged when we merge the template.
     TD->setDescribedAliasTemplate(Template);
   else
@@ -640,27 +613,27 @@ ASTDeclReader::RedeclarableResult ASTDeclReader::VisitTagDecl(TagDecl *TD) {
   RedeclarableResult Redecl = VisitRedeclarable(TD);
   VisitTypeDecl(TD);
   
-  TD->IdentifierNamespace = Record[Idx++];
-  TD->setTagKind((TagDecl::TagKind)Record[Idx++]);
+  TD->IdentifierNamespace = Record.readInt();
+  TD->setTagKind((TagDecl::TagKind)Record.readInt());
   if (!isa<CXXRecordDecl>(TD))
-    TD->setCompleteDefinition(Record[Idx++]);
-  TD->setEmbeddedInDeclarator(Record[Idx++]);
-  TD->setFreeStanding(Record[Idx++]);
-  TD->setCompleteDefinitionRequired(Record[Idx++]);
-  TD->setBraceRange(ReadSourceRange(Record, Idx));
+    TD->setCompleteDefinition(Record.readInt());
+  TD->setEmbeddedInDeclarator(Record.readInt());
+  TD->setFreeStanding(Record.readInt());
+  TD->setCompleteDefinitionRequired(Record.readInt());
+  TD->setBraceRange(ReadSourceRange());
   
-  switch (Record[Idx++]) {
+  switch (Record.readInt()) {
   case 0:
     break;
   case 1: { // ExtInfo
     TagDecl::ExtInfo *Info = new (Reader.getContext()) TagDecl::ExtInfo();
-    ReadQualifierInfo(*Info, Record, Idx);
+    ReadQualifierInfo(*Info);
     TD->TypedefNameDeclOrQualifier = Info;
     break;
   }
   case 2: // TypedefNameForAnonDecl
-    NamedDeclForTagDecl = ReadDeclID(Record, Idx);
-    TypedefNameForLinkage = Reader.GetIdentifierInfo(F, Record, Idx);
+    NamedDeclForTagDecl = ReadDeclID();
+    TypedefNameForLinkage = Record.getIdentifierInfo();
     break;
   default:
     llvm_unreachable("unexpected tag info kind");
@@ -673,16 +646,16 @@ ASTDeclReader::RedeclarableResult ASTDeclReader::VisitTagDecl(TagDecl *TD) {
 
 void ASTDeclReader::VisitEnumDecl(EnumDecl *ED) {
   VisitTagDecl(ED);
-  if (TypeSourceInfo *TI = Reader.GetTypeSourceInfo(F, Record, Idx))
+  if (TypeSourceInfo *TI = GetTypeSourceInfo())
     ED->setIntegerTypeSourceInfo(TI);
   else
-    ED->setIntegerType(Reader.readType(F, Record, Idx));
-  ED->setPromotionType(Reader.readType(F, Record, Idx));
-  ED->setNumPositiveBits(Record[Idx++]);
-  ED->setNumNegativeBits(Record[Idx++]);
-  ED->IsScoped = Record[Idx++];
-  ED->IsScopedUsingClassTag = Record[Idx++];
-  ED->IsFixed = Record[Idx++];
+    ED->setIntegerType(Record.readType());
+  ED->setPromotionType(Record.readType());
+  ED->setNumPositiveBits(Record.readInt());
+  ED->setNumNegativeBits(Record.readInt());
+  ED->IsScoped = Record.readInt();
+  ED->IsScopedUsingClassTag = Record.readInt();
+  ED->IsFixed = Record.readInt();
 
   // If this is a definition subject to the ODR, and we already have a
   // definition, merge this one into it.
@@ -703,15 +676,16 @@ void ASTDeclReader::VisitEnumDecl(EnumDecl *ED) {
     if (OldDef) {
       Reader.MergedDeclContexts.insert(std::make_pair(ED, OldDef));
       ED->IsCompleteDefinition = false;
-      mergeDefinitionVisibility(OldDef, ED);
+      Reader.mergeDefinitionVisibility(OldDef, ED);
     } else {
       OldDef = ED;
     }
   }
 
-  if (EnumDecl *InstED = ReadDeclAs<EnumDecl>(Record, Idx)) {
-    TemplateSpecializationKind TSK = (TemplateSpecializationKind)Record[Idx++];
-    SourceLocation POI = ReadSourceLocation(Record, Idx);
+  if (EnumDecl *InstED = ReadDeclAs<EnumDecl>()) {
+    TemplateSpecializationKind TSK =
+        (TemplateSpecializationKind)Record.readInt();
+    SourceLocation POI = ReadSourceLocation();
     ED->setInstantiationOfMemberEnum(Reader.getContext(), InstED, TSK);
     ED->getMemberSpecializationInfo()->setPointOfInstantiation(POI);
   }
@@ -720,33 +694,33 @@ void ASTDeclReader::VisitEnumDecl(EnumDecl *ED) {
 ASTDeclReader::RedeclarableResult
 ASTDeclReader::VisitRecordDeclImpl(RecordDecl *RD) {
   RedeclarableResult Redecl = VisitTagDecl(RD);
-  RD->setHasFlexibleArrayMember(Record[Idx++]);
-  RD->setAnonymousStructOrUnion(Record[Idx++]);
-  RD->setHasObjectMember(Record[Idx++]);
-  RD->setHasVolatileMember(Record[Idx++]);
+  RD->setHasFlexibleArrayMember(Record.readInt());
+  RD->setAnonymousStructOrUnion(Record.readInt());
+  RD->setHasObjectMember(Record.readInt());
+  RD->setHasVolatileMember(Record.readInt());
   return Redecl;
 }
 
 void ASTDeclReader::VisitValueDecl(ValueDecl *VD) {
   VisitNamedDecl(VD);
-  VD->setType(Reader.readType(F, Record, Idx));
+  VD->setType(Record.readType());
 }
 
 void ASTDeclReader::VisitEnumConstantDecl(EnumConstantDecl *ECD) {
   VisitValueDecl(ECD);
-  if (Record[Idx++])
-    ECD->setInitExpr(Reader.ReadExpr(F));
-  ECD->setInitVal(Reader.ReadAPSInt(Record, Idx));
+  if (Record.readInt())
+    ECD->setInitExpr(Record.readExpr());
+  ECD->setInitVal(Record.readAPSInt());
   mergeMergeable(ECD);
 }
 
 void ASTDeclReader::VisitDeclaratorDecl(DeclaratorDecl *DD) {
   VisitValueDecl(DD);
-  DD->setInnerLocStart(ReadSourceLocation(Record, Idx));
-  if (Record[Idx++]) { // hasExtInfo
+  DD->setInnerLocStart(ReadSourceLocation());
+  if (Record.readInt()) { // hasExtInfo
     DeclaratorDecl::ExtInfo *Info
         = new (Reader.getContext()) DeclaratorDecl::ExtInfo();
-    ReadQualifierInfo(*Info, Record, Idx);
+    ReadQualifierInfo(*Info);
     DD->DeclInfo = Info;
   }
 }
@@ -755,74 +729,72 @@ void ASTDeclReader::VisitFunctionDecl(FunctionDecl *FD) {
   RedeclarableResult Redecl = VisitRedeclarable(FD);
   VisitDeclaratorDecl(FD);
 
-  ReadDeclarationNameLoc(FD->DNLoc, FD->getDeclName(), Record, Idx);
-  FD->IdentifierNamespace = Record[Idx++];
-  
+  ReadDeclarationNameLoc(FD->DNLoc, FD->getDeclName());
+  FD->IdentifierNamespace = Record.readInt();
+
   // FunctionDecl's body is handled last at ASTDeclReader::Visit,
   // after everything else is read.
 
-  FD->SClass = (StorageClass)Record[Idx++];
-  FD->IsInline = Record[Idx++];
-  FD->IsInlineSpecified = Record[Idx++];
-  FD->IsVirtualAsWritten = Record[Idx++];
-  FD->IsPure = Record[Idx++];
-  FD->HasInheritedPrototype = Record[Idx++];
-  FD->HasWrittenPrototype = Record[Idx++];
-  FD->IsDeleted = Record[Idx++];
-  FD->IsTrivial = Record[Idx++];
-  FD->IsDefaulted = Record[Idx++];
-  FD->IsExplicitlyDefaulted = Record[Idx++];
-  FD->HasImplicitReturnZero = Record[Idx++];
-  FD->IsConstexpr = Record[Idx++];
-  FD->HasSkippedBody = Record[Idx++];
-  FD->IsLateTemplateParsed = Record[Idx++];
-  FD->setCachedLinkage(Linkage(Record[Idx++]));
-  FD->EndRangeLoc = ReadSourceLocation(Record, Idx);
-
-  switch ((FunctionDecl::TemplatedKind)Record[Idx++]) {
+  FD->SClass = (StorageClass)Record.readInt();
+  FD->IsInline = Record.readInt();
+  FD->IsInlineSpecified = Record.readInt();
+  FD->IsVirtualAsWritten = Record.readInt();
+  FD->IsPure = Record.readInt();
+  FD->HasInheritedPrototype = Record.readInt();
+  FD->HasWrittenPrototype = Record.readInt();
+  FD->IsDeleted = Record.readInt();
+  FD->IsTrivial = Record.readInt();
+  FD->IsDefaulted = Record.readInt();
+  FD->IsExplicitlyDefaulted = Record.readInt();
+  FD->HasImplicitReturnZero = Record.readInt();
+  FD->IsConstexpr = Record.readInt();
+  FD->HasSkippedBody = Record.readInt();
+  FD->IsLateTemplateParsed = Record.readInt();
+  FD->setCachedLinkage(Linkage(Record.readInt()));
+  FD->EndRangeLoc = ReadSourceLocation();
+
+  switch ((FunctionDecl::TemplatedKind)Record.readInt()) {
   case FunctionDecl::TK_NonTemplate:
     mergeRedeclarable(FD, Redecl);
     break;
   case FunctionDecl::TK_FunctionTemplate:
     // Merged when we merge the template.
-    FD->setDescribedFunctionTemplate(ReadDeclAs<FunctionTemplateDecl>(Record, 
-                                                                      Idx));
+    FD->setDescribedFunctionTemplate(ReadDeclAs<FunctionTemplateDecl>());
     break;
   case FunctionDecl::TK_MemberSpecialization: {
-    FunctionDecl *InstFD = ReadDeclAs<FunctionDecl>(Record, Idx);
-    TemplateSpecializationKind TSK = (TemplateSpecializationKind)Record[Idx++];
-    SourceLocation POI = ReadSourceLocation(Record, Idx);
+    FunctionDecl *InstFD = ReadDeclAs<FunctionDecl>();
+    TemplateSpecializationKind TSK =
+        (TemplateSpecializationKind)Record.readInt();
+    SourceLocation POI = ReadSourceLocation();
     FD->setInstantiationOfMemberFunction(Reader.getContext(), InstFD, TSK);
     FD->getMemberSpecializationInfo()->setPointOfInstantiation(POI);
     mergeRedeclarable(FD, Redecl);
     break;
   }
   case FunctionDecl::TK_FunctionTemplateSpecialization: {
-    FunctionTemplateDecl *Template = ReadDeclAs<FunctionTemplateDecl>(Record, 
-                                                                      Idx);
-    TemplateSpecializationKind TSK = (TemplateSpecializationKind)Record[Idx++];
-    
+    FunctionTemplateDecl *Template = ReadDeclAs<FunctionTemplateDecl>();
+    TemplateSpecializationKind TSK =
+        (TemplateSpecializationKind)Record.readInt();
+
     // Template arguments.
     SmallVector<TemplateArgument, 8> TemplArgs;
-    Reader.ReadTemplateArgumentList(TemplArgs, F, Record, Idx,
-                                    /*Canonicalize*/ true);
+    Record.readTemplateArgumentList(TemplArgs, /*Canonicalize*/ true);
 
     // Template args as written.
     SmallVector<TemplateArgumentLoc, 8> TemplArgLocs;
     SourceLocation LAngleLoc, RAngleLoc;
-    bool HasTemplateArgumentsAsWritten = Record[Idx++];
+    bool HasTemplateArgumentsAsWritten = Record.readInt();
     if (HasTemplateArgumentsAsWritten) {
-      unsigned NumTemplateArgLocs = Record[Idx++];
+      unsigned NumTemplateArgLocs = Record.readInt();
       TemplArgLocs.reserve(NumTemplateArgLocs);
       for (unsigned i=0; i != NumTemplateArgLocs; ++i)
-        TemplArgLocs.push_back(
-            Reader.ReadTemplateArgumentLoc(F, Record, Idx));
-  
-      LAngleLoc = ReadSourceLocation(Record, Idx);
-      RAngleLoc = ReadSourceLocation(Record, Idx);
+        TemplArgLocs.push_back(Record.readTemplateArgumentLoc());
+
+      LAngleLoc = ReadSourceLocation();
+      RAngleLoc = ReadSourceLocation();
     }
-    
-    SourceLocation POI = ReadSourceLocation(Record, Idx);
+
+    SourceLocation POI = ReadSourceLocation();
 
     ASTContext &C = Reader.getContext();
     TemplateArgumentList *TemplArgList
@@ -841,8 +813,7 @@ void ASTDeclReader::VisitFunctionDecl(FunctionDecl *FD) {
     if (FD->isCanonicalDecl()) { // if canonical add to template's set.
       // The template that contains the specializations set. It's not safe to
       // use getCanonicalDecl on Template since it may still be initializing.
-      FunctionTemplateDecl *CanonTemplate
-        = ReadDeclAs<FunctionTemplateDecl>(Record, Idx);
+      FunctionTemplateDecl *CanonTemplate = ReadDeclAs<FunctionTemplateDecl>();
       // Get the InsertPos by FindNodeOrInsertPos() instead of calling
       // InsertNode(FTInfo) directly to avoid the getASTContext() call in
       // FunctionTemplateSpecializationInfo's Profile().
@@ -867,18 +838,18 @@ void ASTDeclReader::VisitFunctionDecl(FunctionDecl *FD) {
   case FunctionDecl::TK_DependentFunctionTemplateSpecialization: {
     // Templates.
     UnresolvedSet<8> TemplDecls;
-    unsigned NumTemplates = Record[Idx++];
+    unsigned NumTemplates = Record.readInt();
     while (NumTemplates--)
-      TemplDecls.addDecl(ReadDeclAs<NamedDecl>(Record, Idx));
-    
+      TemplDecls.addDecl(ReadDeclAs<NamedDecl>());
+
     // Templates args.
     TemplateArgumentListInfo TemplArgs;
-    unsigned NumArgs = Record[Idx++];
+    unsigned NumArgs = Record.readInt();
     while (NumArgs--)
-      TemplArgs.addArgument(Reader.ReadTemplateArgumentLoc(F, Record, Idx));
-    TemplArgs.setLAngleLoc(ReadSourceLocation(Record, Idx));
-    TemplArgs.setRAngleLoc(ReadSourceLocation(Record, Idx));
-    
+      TemplArgs.addArgument(Record.readTemplateArgumentLoc());
+    TemplArgs.setLAngleLoc(ReadSourceLocation());
+    TemplArgs.setRAngleLoc(ReadSourceLocation());
+
     FD->setDependentTemplateSpecialization(Reader.getContext(),
                                            TemplDecls, TemplArgs);
     // These are not merged; we don't need to merge redeclarations of dependent
@@ -888,55 +859,55 @@ void ASTDeclReader::VisitFunctionDecl(FunctionDecl *FD) {
   }
 
   // Read in the parameters.
-  unsigned NumParams = Record[Idx++];
+  unsigned NumParams = Record.readInt();
   SmallVector<ParmVarDecl *, 16> Params;
   Params.reserve(NumParams);
   for (unsigned I = 0; I != NumParams; ++I)
-    Params.push_back(ReadDeclAs<ParmVarDecl>(Record, Idx));
+    Params.push_back(ReadDeclAs<ParmVarDecl>());
   FD->setParams(Reader.getContext(), Params);
 }
 
 void ASTDeclReader::VisitObjCMethodDecl(ObjCMethodDecl *MD) {
   VisitNamedDecl(MD);
-  if (Record[Idx++]) {
+  if (Record.readInt()) {
     // Load the body on-demand. Most clients won't care, because method
     // definitions rarely show up in headers.
     Reader.PendingBodies[MD] = GetCurrentCursorOffset();
     HasPendingBody = true;
-    MD->setSelfDecl(ReadDeclAs<ImplicitParamDecl>(Record, Idx));
-    MD->setCmdDecl(ReadDeclAs<ImplicitParamDecl>(Record, Idx));
-  }
-  MD->setInstanceMethod(Record[Idx++]);
-  MD->setVariadic(Record[Idx++]);
-  MD->setPropertyAccessor(Record[Idx++]);
-  MD->setDefined(Record[Idx++]);
-  MD->IsOverriding = Record[Idx++];
-  MD->HasSkippedBody = Record[Idx++];
-
-  MD->IsRedeclaration = Record[Idx++];
-  MD->HasRedeclaration = Record[Idx++];
+    MD->setSelfDecl(ReadDeclAs<ImplicitParamDecl>());
+    MD->setCmdDecl(ReadDeclAs<ImplicitParamDecl>());
+  }
+  MD->setInstanceMethod(Record.readInt());
+  MD->setVariadic(Record.readInt());
+  MD->setPropertyAccessor(Record.readInt());
+  MD->setDefined(Record.readInt());
+  MD->IsOverriding = Record.readInt();
+  MD->HasSkippedBody = Record.readInt();
+
+  MD->IsRedeclaration = Record.readInt();
+  MD->HasRedeclaration = Record.readInt();
   if (MD->HasRedeclaration)
     Reader.getContext().setObjCMethodRedeclaration(MD,
-                                       ReadDeclAs<ObjCMethodDecl>(Record, Idx));
-
-  MD->setDeclImplementation((ObjCMethodDecl::ImplementationControl)Record[Idx++]);
-  MD->setObjCDeclQualifier((Decl::ObjCDeclQualifier)Record[Idx++]);
-  MD->SetRelatedResultType(Record[Idx++]);
-  MD->setReturnType(Reader.readType(F, Record, Idx));
-  MD->setReturnTypeSourceInfo(GetTypeSourceInfo(Record, Idx));
-  MD->DeclEndLoc = ReadSourceLocation(Record, Idx);
-  unsigned NumParams = Record[Idx++];
+                                       ReadDeclAs<ObjCMethodDecl>());
+
+  MD->setDeclImplementation((ObjCMethodDecl::ImplementationControl)Record.readInt());
+  MD->setObjCDeclQualifier((Decl::ObjCDeclQualifier)Record.readInt());
+  MD->SetRelatedResultType(Record.readInt());
+  MD->setReturnType(Record.readType());
+  MD->setReturnTypeSourceInfo(GetTypeSourceInfo());
+  MD->DeclEndLoc = ReadSourceLocation();
+  unsigned NumParams = Record.readInt();
   SmallVector<ParmVarDecl *, 16> Params;
   Params.reserve(NumParams);
   for (unsigned I = 0; I != NumParams; ++I)
-    Params.push_back(ReadDeclAs<ParmVarDecl>(Record, Idx));
+    Params.push_back(ReadDeclAs<ParmVarDecl>());
 
-  MD->SelLocsKind = Record[Idx++];
-  unsigned NumStoredSelLocs = Record[Idx++];
+  MD->SelLocsKind = Record.readInt();
+  unsigned NumStoredSelLocs = Record.readInt();
   SmallVector<SourceLocation, 16> SelLocs;
   SelLocs.reserve(NumStoredSelLocs);
   for (unsigned i = 0; i != NumStoredSelLocs; ++i)
-    SelLocs.push_back(ReadSourceLocation(Record, Idx));
+    SelLocs.push_back(ReadSourceLocation());
 
   MD->setParamsAndSelLocs(Reader.getContext(), Params, SelLocs);
 }
@@ -944,91 +915,106 @@ void ASTDeclReader::VisitObjCMethodDecl(ObjCMethodDecl *MD) {
 void ASTDeclReader::VisitObjCTypeParamDecl(ObjCTypeParamDecl *D) {
   VisitTypedefNameDecl(D);
 
-  D->Variance = Record[Idx++];
-  D->Index = Record[Idx++];
-  D->VarianceLoc = ReadSourceLocation(Record, Idx);
-  D->ColonLoc = ReadSourceLocation(Record, Idx);
+  D->Variance = Record.readInt();
+  D->Index = Record.readInt();
+  D->VarianceLoc = ReadSourceLocation();
+  D->ColonLoc = ReadSourceLocation();
 }
 
 void ASTDeclReader::VisitObjCContainerDecl(ObjCContainerDecl *CD) {
   VisitNamedDecl(CD);
-  CD->setAtStartLoc(ReadSourceLocation(Record, Idx));
-  CD->setAtEndRange(ReadSourceRange(Record, Idx));
+  CD->setAtStartLoc(ReadSourceLocation());
+  CD->setAtEndRange(ReadSourceRange());
 }
 
 ObjCTypeParamList *ASTDeclReader::ReadObjCTypeParamList() {
-  unsigned numParams = Record[Idx++];
+  unsigned numParams = Record.readInt();
   if (numParams == 0)
     return nullptr;
 
   SmallVector<ObjCTypeParamDecl *, 4> typeParams;
   typeParams.reserve(numParams);
   for (unsigned i = 0; i != numParams; ++i) {
-    auto typeParam = ReadDeclAs<ObjCTypeParamDecl>(Record, Idx);
+    auto typeParam = ReadDeclAs<ObjCTypeParamDecl>();
     if (!typeParam)
       return nullptr;
 
     typeParams.push_back(typeParam);
   }
 
-  SourceLocation lAngleLoc = ReadSourceLocation(Record, Idx);
-  SourceLocation rAngleLoc = ReadSourceLocation(Record, Idx);
+  SourceLocation lAngleLoc = ReadSourceLocation();
+  SourceLocation rAngleLoc = ReadSourceLocation();
 
   return ObjCTypeParamList::create(Reader.getContext(), lAngleLoc,
                                    typeParams, rAngleLoc);
 }
 
+void ASTDeclReader::ReadObjCDefinitionData(
+         struct ObjCInterfaceDecl::DefinitionData &Data) {
+  // Read the superclass.
+  Data.SuperClassTInfo = GetTypeSourceInfo();
+
+  Data.EndLoc = ReadSourceLocation();
+  Data.HasDesignatedInitializers = Record.readInt();
+
+  // Read the directly referenced protocols and their SourceLocations.
+  unsigned NumProtocols = Record.readInt();
+  SmallVector<ObjCProtocolDecl *, 16> Protocols;
+  Protocols.reserve(NumProtocols);
+  for (unsigned I = 0; I != NumProtocols; ++I)
+    Protocols.push_back(ReadDeclAs<ObjCProtocolDecl>());
+  SmallVector<SourceLocation, 16> ProtoLocs;
+  ProtoLocs.reserve(NumProtocols);
+  for (unsigned I = 0; I != NumProtocols; ++I)
+    ProtoLocs.push_back(ReadSourceLocation());
+  Data.ReferencedProtocols.set(Protocols.data(), NumProtocols, ProtoLocs.data(),
+                               Reader.getContext());
+
+  // Read the transitive closure of protocols referenced by this class.
+  NumProtocols = Record.readInt();
+  Protocols.clear();
+  Protocols.reserve(NumProtocols);
+  for (unsigned I = 0; I != NumProtocols; ++I)
+    Protocols.push_back(ReadDeclAs<ObjCProtocolDecl>());
+  Data.AllReferencedProtocols.set(Protocols.data(), NumProtocols,
+                                  Reader.getContext());
+}
+
+void ASTDeclReader::MergeDefinitionData(ObjCInterfaceDecl *D,
+         struct ObjCInterfaceDecl::DefinitionData &&NewDD) {
+  // FIXME: odr checking?
+}
+
 void ASTDeclReader::VisitObjCInterfaceDecl(ObjCInterfaceDecl *ID) {
   RedeclarableResult Redecl = VisitRedeclarable(ID);
   VisitObjCContainerDecl(ID);
-  TypeIDForTypeDecl = Reader.getGlobalTypeID(F, Record[Idx++]);
+  TypeIDForTypeDecl = Record.getGlobalTypeID(Record.readInt());
   mergeRedeclarable(ID, Redecl);
 
   ID->TypeParamList = ReadObjCTypeParamList();
-  if (Record[Idx++]) {
+  if (Record.readInt()) {
     // Read the definition.
     ID->allocateDefinitionData();
-    
-    // Set the definition data of the canonical declaration, so other
-    // redeclarations will see it.
-    ID->getCanonicalDecl()->Data = ID->Data;
-    
-    ObjCInterfaceDecl::DefinitionData &Data = ID->data();
-    
-    // Read the superclass.
-    Data.SuperClassTInfo = GetTypeSourceInfo(Record, Idx);
 
-    Data.EndLoc = ReadSourceLocation(Record, Idx);
-    Data.HasDesignatedInitializers = Record[Idx++];
-    
-    // Read the directly referenced protocols and their SourceLocations.
-    unsigned NumProtocols = Record[Idx++];
-    SmallVector<ObjCProtocolDecl *, 16> Protocols;
-    Protocols.reserve(NumProtocols);
-    for (unsigned I = 0; I != NumProtocols; ++I)
-      Protocols.push_back(ReadDeclAs<ObjCProtocolDecl>(Record, Idx));
-    SmallVector<SourceLocation, 16> ProtoLocs;
-    ProtoLocs.reserve(NumProtocols);
-    for (unsigned I = 0; I != NumProtocols; ++I)
-      ProtoLocs.push_back(ReadSourceLocation(Record, Idx));
-    ID->setProtocolList(Protocols.data(), NumProtocols, ProtoLocs.data(),
-                        Reader.getContext());
-  
-    // Read the transitive closure of protocols referenced by this class.
-    NumProtocols = Record[Idx++];
-    Protocols.clear();
-    Protocols.reserve(NumProtocols);
-    for (unsigned I = 0; I != NumProtocols; ++I)
-      Protocols.push_back(ReadDeclAs<ObjCProtocolDecl>(Record, Idx));
-    ID->data().AllReferencedProtocols.set(Protocols.data(), NumProtocols,
-                                          Reader.getContext());
-  
-    // We will rebuild this list lazily.
-    ID->setIvarList(nullptr);
+    ReadObjCDefinitionData(ID->data());
+    ObjCInterfaceDecl *Canon = ID->getCanonicalDecl();
+    if (Canon->Data.getPointer()) {
+      // If we already have a definition, keep the definition invariant and
+      // merge the data.
+      MergeDefinitionData(Canon, std::move(ID->data()));
+      ID->Data = Canon->Data;
+    } else {
+      // Set the definition data of the canonical declaration, so other
+      // redeclarations will see it.
+      ID->getCanonicalDecl()->Data = ID->Data;
+
+      // We will rebuild this list lazily.
+      ID->setIvarList(nullptr);
+    }
 
     // Note that we have deserialized a definition.
     Reader.PendingDefinitions.insert(ID);
-    
+
     // Note that we've loaded this Objective-C class.
     Reader.ObjCClassesLoaded.push_back(ID);
   } else {
@@ -1038,10 +1024,10 @@ void ASTDeclReader::VisitObjCInterfaceDecl(ObjCInterfaceDecl *ID) {
 
 void ASTDeclReader::VisitObjCIvarDecl(ObjCIvarDecl *IVD) {
   VisitFieldDecl(IVD);
-  IVD->setAccessControl((ObjCIvarDecl::AccessControl)Record[Idx++]);
+  IVD->setAccessControl((ObjCIvarDecl::AccessControl)Record.readInt());
   // This field will be built lazily.
   IVD->setNextIvar(nullptr);
-  bool synth = Record[Idx++];
+  bool synth = Record.readInt();
   IVD->setSynthesize(synth);
 }
 
@@ -1049,27 +1035,27 @@ void ASTDeclReader::VisitObjCProtocolDecl(ObjCProtocolDecl *PD) {
   RedeclarableResult Redecl = VisitRedeclarable(PD);
   VisitObjCContainerDecl(PD);
   mergeRedeclarable(PD, Redecl);
-  
-  if (Record[Idx++]) {
+
+  if (Record.readInt()) {
     // Read the definition.
     PD->allocateDefinitionData();
-    
+
     // Set the definition data of the canonical declaration, so other
     // redeclarations will see it.
     PD->getCanonicalDecl()->Data = PD->Data;
 
-    unsigned NumProtoRefs = Record[Idx++];
+    unsigned NumProtoRefs = Record.readInt();
     SmallVector<ObjCProtocolDecl *, 16> ProtoRefs;
     ProtoRefs.reserve(NumProtoRefs);
     for (unsigned I = 0; I != NumProtoRefs; ++I)
-      ProtoRefs.push_back(ReadDeclAs<ObjCProtocolDecl>(Record, Idx));
+      ProtoRefs.push_back(ReadDeclAs<ObjCProtocolDecl>());
     SmallVector<SourceLocation, 16> ProtoLocs;
     ProtoLocs.reserve(NumProtoRefs);
     for (unsigned I = 0; I != NumProtoRefs; ++I)
-      ProtoLocs.push_back(ReadSourceLocation(Record, Idx));
+      ProtoLocs.push_back(ReadSourceLocation());
     PD->setProtocolList(ProtoRefs.data(), NumProtoRefs, ProtoLocs.data(),
                         Reader.getContext());
-    
+
     // Note that we have deserialized a definition.
     Reader.PendingDefinitions.insert(PD);
   } else {
@@ -1083,105 +1069,104 @@ void ASTDeclReader::VisitObjCAtDefsFieldDecl(ObjCAtDefsFieldDecl *FD) {
 
 void ASTDeclReader::VisitObjCCategoryDecl(ObjCCategoryDecl *CD) {
   VisitObjCContainerDecl(CD);
-  CD->setCategoryNameLoc(ReadSourceLocation(Record, Idx));
-  CD->setIvarLBraceLoc(ReadSourceLocation(Record, Idx));
-  CD->setIvarRBraceLoc(ReadSourceLocation(Record, Idx));
-  
+  CD->setCategoryNameLoc(ReadSourceLocation());
+  CD->setIvarLBraceLoc(ReadSourceLocation());
+  CD->setIvarRBraceLoc(ReadSourceLocation());
+
   // Note that this category has been deserialized. We do this before
   // deserializing the interface declaration, so that it will consider this
   /// category.
   Reader.CategoriesDeserialized.insert(CD);
 
-  CD->ClassInterface = ReadDeclAs<ObjCInterfaceDecl>(Record, Idx);
+  CD->ClassInterface = ReadDeclAs<ObjCInterfaceDecl>();
   CD->TypeParamList = ReadObjCTypeParamList();
-  unsigned NumProtoRefs = Record[Idx++];
+  unsigned NumProtoRefs = Record.readInt();
   SmallVector<ObjCProtocolDecl *, 16> ProtoRefs;
   ProtoRefs.reserve(NumProtoRefs);
   for (unsigned I = 0; I != NumProtoRefs; ++I)
-    ProtoRefs.push_back(ReadDeclAs<ObjCProtocolDecl>(Record, Idx));
+    ProtoRefs.push_back(ReadDeclAs<ObjCProtocolDecl>());
   SmallVector<SourceLocation, 16> ProtoLocs;
   ProtoLocs.reserve(NumProtoRefs);
   for (unsigned I = 0; I != NumProtoRefs; ++I)
-    ProtoLocs.push_back(ReadSourceLocation(Record, Idx));
+    ProtoLocs.push_back(ReadSourceLocation());
   CD->setProtocolList(ProtoRefs.data(), NumProtoRefs, ProtoLocs.data(),
                       Reader.getContext());
 }
 
 void ASTDeclReader::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *CAD) {
   VisitNamedDecl(CAD);
-  CAD->setClassInterface(ReadDeclAs<ObjCInterfaceDecl>(Record, Idx));
+  CAD->setClassInterface(ReadDeclAs<ObjCInterfaceDecl>());
 }
 
 void ASTDeclReader::VisitObjCPropertyDecl(ObjCPropertyDecl *D) {
   VisitNamedDecl(D);
-  D->setAtLoc(ReadSourceLocation(Record, Idx));
-  D->setLParenLoc(ReadSourceLocation(Record, Idx));
-  QualType T = Reader.readType(F, Record, Idx);
-  TypeSourceInfo *TSI = GetTypeSourceInfo(Record, Idx);
+  D->setAtLoc(ReadSourceLocation());
+  D->setLParenLoc(ReadSourceLocation());
+  QualType T = Record.readType();
+  TypeSourceInfo *TSI = GetTypeSourceInfo();
   D->setType(T, TSI);
   D->setPropertyAttributes(
-                      (ObjCPropertyDecl::PropertyAttributeKind)Record[Idx++]);
+      (ObjCPropertyDecl::PropertyAttributeKind)Record.readInt());
   D->setPropertyAttributesAsWritten(
-                      (ObjCPropertyDecl::PropertyAttributeKind)Record[Idx++]);
+      (ObjCPropertyDecl::PropertyAttributeKind)Record.readInt());
   D->setPropertyImplementation(
-                            (ObjCPropertyDecl::PropertyControl)Record[Idx++]);
-  D->setGetterName(Reader.ReadDeclarationName(F,Record, Idx).getObjCSelector());
-  D->setSetterName(Reader.ReadDeclarationName(F,Record, Idx).getObjCSelector());
-  D->setGetterMethodDecl(ReadDeclAs<ObjCMethodDecl>(Record, Idx));
-  D->setSetterMethodDecl(ReadDeclAs<ObjCMethodDecl>(Record, Idx));
-  D->setPropertyIvarDecl(ReadDeclAs<ObjCIvarDecl>(Record, Idx));
+      (ObjCPropertyDecl::PropertyControl)Record.readInt());
+  D->setGetterName(Record.readDeclarationName().getObjCSelector());
+  D->setSetterName(Record.readDeclarationName().getObjCSelector());
+  D->setGetterMethodDecl(ReadDeclAs<ObjCMethodDecl>());
+  D->setSetterMethodDecl(ReadDeclAs<ObjCMethodDecl>());
+  D->setPropertyIvarDecl(ReadDeclAs<ObjCIvarDecl>());
 }
 
 void ASTDeclReader::VisitObjCImplDecl(ObjCImplDecl *D) {
   VisitObjCContainerDecl(D);
-  D->setClassInterface(ReadDeclAs<ObjCInterfaceDecl>(Record, Idx));
+  D->setClassInterface(ReadDeclAs<ObjCInterfaceDecl>());
 }
 
 void ASTDeclReader::VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *D) {
   VisitObjCImplDecl(D);
-  D->setIdentifier(Reader.GetIdentifierInfo(F, Record, Idx));
-  D->CategoryNameLoc = ReadSourceLocation(Record, Idx);
+  D->setIdentifier(Record.getIdentifierInfo());
+  D->CategoryNameLoc = ReadSourceLocation();
 }
 
 void ASTDeclReader::VisitObjCImplementationDecl(ObjCImplementationDecl *D) {
   VisitObjCImplDecl(D);
-  D->setSuperClass(ReadDeclAs<ObjCInterfaceDecl>(Record, Idx));
-  D->SuperLoc = ReadSourceLocation(Record, Idx);
-  D->setIvarLBraceLoc(ReadSourceLocation(Record, Idx));
-  D->setIvarRBraceLoc(ReadSourceLocation(Record, Idx));
-  D->setHasNonZeroConstructors(Record[Idx++]);
-  D->setHasDestructors(Record[Idx++]);
-  D->NumIvarInitializers = Record[Idx++];
+  D->setSuperClass(ReadDeclAs<ObjCInterfaceDecl>());
+  D->SuperLoc = ReadSourceLocation();
+  D->setIvarLBraceLoc(ReadSourceLocation());
+  D->setIvarRBraceLoc(ReadSourceLocation());
+  D->setHasNonZeroConstructors(Record.readInt());
+  D->setHasDestructors(Record.readInt());
+  D->NumIvarInitializers = Record.readInt();
   if (D->NumIvarInitializers)
-    D->IvarInitializers = ReadGlobalOffset(F, Record, Idx);
+    D->IvarInitializers = ReadGlobalOffset();
 }
 
 void ASTDeclReader::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
   VisitDecl(D);
-  D->setAtLoc(ReadSourceLocation(Record, Idx));
-  D->setPropertyDecl(ReadDeclAs<ObjCPropertyDecl>(Record, Idx));
-  D->PropertyIvarDecl = ReadDeclAs<ObjCIvarDecl>(Record, Idx);
-  D->IvarLoc = ReadSourceLocation(Record, Idx);
-  D->setGetterCXXConstructor(Reader.ReadExpr(F));
-  D->setSetterCXXAssignment(Reader.ReadExpr(F));
+  D->setAtLoc(ReadSourceLocation());
+  D->setPropertyDecl(ReadDeclAs<ObjCPropertyDecl>());
+  D->PropertyIvarDecl = ReadDeclAs<ObjCIvarDecl>();
+  D->IvarLoc = ReadSourceLocation();
+  D->setGetterCXXConstructor(Record.readExpr());
+  D->setSetterCXXAssignment(Record.readExpr());
 }
 
 void ASTDeclReader::VisitFieldDecl(FieldDecl *FD) {
   VisitDeclaratorDecl(FD);
-  FD->Mutable = Record[Idx++];
-  if (int BitWidthOrInitializer = Record[Idx++]) {
+  FD->Mutable = Record.readInt();
+  if (int BitWidthOrInitializer = Record.readInt()) {
     FD->InitStorage.setInt(
           static_cast<FieldDecl::InitStorageKind>(BitWidthOrInitializer - 1));
     if (FD->InitStorage.getInt() == FieldDecl::ISK_CapturedVLAType) {
       // Read captured variable length array.
-      FD->InitStorage.setPointer(
-          Reader.readType(F, Record, Idx).getAsOpaquePtr());
+      FD->InitStorage.setPointer(Record.readType().getAsOpaquePtr());
     } else {
-      FD->InitStorage.setPointer(Reader.ReadExpr(F));
+      FD->InitStorage.setPointer(Record.readExpr());
     }
   }
   if (!FD->getDeclName()) {
-    if (FieldDecl *Tmpl = ReadDeclAs<FieldDecl>(Record, Idx))
+    if (FieldDecl *Tmpl = ReadDeclAs<FieldDecl>())
       Reader.getContext().setInstantiatedFromUnnamedFieldDecl(FD, Tmpl);
   }
   mergeMergeable(FD);
@@ -1189,19 +1174,19 @@ void ASTDeclReader::VisitFieldDecl(FieldDecl *FD) {
 
 void ASTDeclReader::VisitMSPropertyDecl(MSPropertyDecl *PD) {
   VisitDeclaratorDecl(PD);
-  PD->GetterId = Reader.GetIdentifierInfo(F, Record, Idx);
-  PD->SetterId = Reader.GetIdentifierInfo(F, Record, Idx);
+  PD->GetterId = Record.getIdentifierInfo();
+  PD->SetterId = Record.getIdentifierInfo();
 }
 
 void ASTDeclReader::VisitIndirectFieldDecl(IndirectFieldDecl *FD) {
   VisitValueDecl(FD);
 
-  FD->ChainingSize = Record[Idx++];
+  FD->ChainingSize = Record.readInt();
   assert(FD->ChainingSize >= 2 && "Anonymous chaining must be >= 2");
   FD->Chaining = new (Reader.getContext())NamedDecl*[FD->ChainingSize];
 
   for (unsigned I = 0; I != FD->ChainingSize; ++I)
-    FD->Chaining[I] = ReadDeclAs<NamedDecl>(Record, Idx);
+    FD->Chaining[I] = ReadDeclAs<NamedDecl>();
 
   mergeMergeable(FD);
 }
@@ -1210,21 +1195,23 @@ ASTDeclReader::RedeclarableResult ASTDeclReader::VisitVarDeclImpl(VarDecl *VD) {
   RedeclarableResult Redecl = VisitRedeclarable(VD);
   VisitDeclaratorDecl(VD);
 
-  VD->VarDeclBits.SClass = (StorageClass)Record[Idx++];
-  VD->VarDeclBits.TSCSpec = Record[Idx++];
-  VD->VarDeclBits.InitStyle = Record[Idx++];
+  VD->VarDeclBits.SClass = (StorageClass)Record.readInt();
+  VD->VarDeclBits.TSCSpec = Record.readInt();
+  VD->VarDeclBits.InitStyle = Record.readInt();
   if (!isa<ParmVarDecl>(VD)) {
-    VD->NonParmVarDeclBits.ExceptionVar = Record[Idx++];
-    VD->NonParmVarDeclBits.NRVOVariable = Record[Idx++];
-    VD->NonParmVarDeclBits.CXXForRangeDecl = Record[Idx++];
-    VD->NonParmVarDeclBits.ARCPseudoStrong = Record[Idx++];
-    VD->NonParmVarDeclBits.IsInline = Record[Idx++];
-    VD->NonParmVarDeclBits.IsInlineSpecified = Record[Idx++];
-    VD->NonParmVarDeclBits.IsConstexpr = Record[Idx++];
-    VD->NonParmVarDeclBits.IsInitCapture = Record[Idx++];
-    VD->NonParmVarDeclBits.PreviousDeclInSameBlockScope = Record[Idx++];
-  }
-  Linkage VarLinkage = Linkage(Record[Idx++]);
+    VD->NonParmVarDeclBits.IsThisDeclarationADemotedDefinition =
+        Record.readInt();
+    VD->NonParmVarDeclBits.ExceptionVar = Record.readInt();
+    VD->NonParmVarDeclBits.NRVOVariable = Record.readInt();
+    VD->NonParmVarDeclBits.CXXForRangeDecl = Record.readInt();
+    VD->NonParmVarDeclBits.ARCPseudoStrong = Record.readInt();
+    VD->NonParmVarDeclBits.IsInline = Record.readInt();
+    VD->NonParmVarDeclBits.IsInlineSpecified = Record.readInt();
+    VD->NonParmVarDeclBits.IsConstexpr = Record.readInt();
+    VD->NonParmVarDeclBits.IsInitCapture = Record.readInt();
+    VD->NonParmVarDeclBits.PreviousDeclInSameBlockScope = Record.readInt();
+  }
+  Linkage VarLinkage = Linkage(Record.readInt());
   VD->setCachedLinkage(VarLinkage);
 
   // Reconstruct the one piece of the IdentifierNamespace that we need.
@@ -1232,9 +1219,9 @@ ASTDeclReader::RedeclarableResult ASTDeclReader::VisitVarDeclImpl(VarDecl *VD) {
       VD->getLexicalDeclContext()->isFunctionOrMethod())
     VD->setLocalExternDecl();
 
-  if (uint64_t Val = Record[Idx++]) {
-    VD->setInit(Reader.ReadExpr(F));
-    if (Val > 1) {
+  if (uint64_t Val = Record.readInt()) {
+    VD->setInit(Record.readExpr());
+    if (Val > 1) { // IsInitKnownICE = 1, IsInitNotICE = 2, IsInitICE = 3
       EvaluatedStmt *Eval = VD->ensureEvaluatedStmt();
       Eval->CheckedICE = true;
       Eval->IsICE = Val == 3;
@@ -1244,7 +1231,7 @@ ASTDeclReader::RedeclarableResult ASTDeclReader::VisitVarDeclImpl(VarDecl *VD) {
   enum VarKind {
     VarNotTemplate = 0, VarTemplate, StaticDataMemberSpecialization
   };
-  switch ((VarKind)Record[Idx++]) {
+  switch ((VarKind)Record.readInt()) {
   case VarNotTemplate:
     // Only true variables (not parameters or implicit parameters) can be
     // merged; the other kinds are not really redeclarable at all.
@@ -1254,12 +1241,13 @@ ASTDeclReader::RedeclarableResult ASTDeclReader::VisitVarDeclImpl(VarDecl *VD) {
     break;
   case VarTemplate:
     // Merged when we merge the template.
-    VD->setDescribedVarTemplate(ReadDeclAs<VarTemplateDecl>(Record, Idx));
+    VD->setDescribedVarTemplate(ReadDeclAs<VarTemplateDecl>());
     break;
   case StaticDataMemberSpecialization: { // HasMemberSpecializationInfo.
-    VarDecl *Tmpl = ReadDeclAs<VarDecl>(Record, Idx);
-    TemplateSpecializationKind TSK = (TemplateSpecializationKind)Record[Idx++];
-    SourceLocation POI = ReadSourceLocation(Record, Idx);
+    VarDecl *Tmpl = ReadDeclAs<VarDecl>();
+    TemplateSpecializationKind TSK =
+        (TemplateSpecializationKind)Record.readInt();
+    SourceLocation POI = ReadSourceLocation();
     Reader.getContext().setInstantiatedFromStaticDataMember(VD, Tmpl, TSK,POI);
     mergeRedeclarable(VD, Redecl);
     break;
@@ -1275,10 +1263,10 @@ void ASTDeclReader::VisitImplicitParamDecl(ImplicitParamDecl *PD) {
 
 void ASTDeclReader::VisitParmVarDecl(ParmVarDecl *PD) {
   VisitVarDecl(PD);
-  unsigned isObjCMethodParam = Record[Idx++];
-  unsigned scopeDepth = Record[Idx++];
-  unsigned scopeIndex = Record[Idx++];
-  unsigned declQualifier = Record[Idx++];
+  unsigned isObjCMethodParam = Record.readInt();
+  unsigned scopeDepth = Record.readInt();
+  unsigned scopeIndex = Record.readInt();
+  unsigned declQualifier = Record.readInt();
   if (isObjCMethodParam) {
     assert(scopeDepth == 0);
     PD->setObjCMethodScopeInfo(scopeIndex);
@@ -1286,46 +1274,58 @@ void ASTDeclReader::VisitParmVarDecl(ParmVarDecl *PD) {
   } else {
     PD->setScopeInfo(scopeDepth, scopeIndex);
   }
-  PD->ParmVarDeclBits.IsKNRPromoted = Record[Idx++];
-  PD->ParmVarDeclBits.HasInheritedDefaultArg = Record[Idx++];
-  if (Record[Idx++]) // hasUninstantiatedDefaultArg.
-    PD->setUninstantiatedDefaultArg(Reader.ReadExpr(F));
+  PD->ParmVarDeclBits.IsKNRPromoted = Record.readInt();
+  PD->ParmVarDeclBits.HasInheritedDefaultArg = Record.readInt();
+  if (Record.readInt()) // hasUninstantiatedDefaultArg.
+    PD->setUninstantiatedDefaultArg(Record.readExpr());
 
   // FIXME: If this is a redeclaration of a function from another module, handle
   // inheritance of default arguments.
 }
 
+void ASTDeclReader::VisitDecompositionDecl(DecompositionDecl *DD) {
+  VisitVarDecl(DD);
+  BindingDecl **BDs = DD->getTrailingObjects<BindingDecl*>();
+  for (unsigned I = 0; I != DD->NumBindings; ++I)
+    BDs[I] = ReadDeclAs<BindingDecl>();
+}
+
+void ASTDeclReader::VisitBindingDecl(BindingDecl *BD) {
+  VisitValueDecl(BD);
+  BD->Binding = Record.readExpr();
+}
+
 void ASTDeclReader::VisitFileScopeAsmDecl(FileScopeAsmDecl *AD) {
   VisitDecl(AD);
-  AD->setAsmString(cast<StringLiteral>(Reader.ReadExpr(F)));
-  AD->setRParenLoc(ReadSourceLocation(Record, Idx));
+  AD->setAsmString(cast<StringLiteral>(Record.readExpr()));
+  AD->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTDeclReader::VisitBlockDecl(BlockDecl *BD) {
   VisitDecl(BD);
-  BD->setBody(cast_or_null<CompoundStmt>(Reader.ReadStmt(F)));
-  BD->setSignatureAsWritten(GetTypeSourceInfo(Record, Idx));
-  unsigned NumParams = Record[Idx++];
+  BD->setBody(cast_or_null<CompoundStmt>(Record.readStmt()));
+  BD->setSignatureAsWritten(GetTypeSourceInfo());
+  unsigned NumParams = Record.readInt();
   SmallVector<ParmVarDecl *, 16> Params;
   Params.reserve(NumParams);
   for (unsigned I = 0; I != NumParams; ++I)
-    Params.push_back(ReadDeclAs<ParmVarDecl>(Record, Idx));
+    Params.push_back(ReadDeclAs<ParmVarDecl>());
   BD->setParams(Params);
 
-  BD->setIsVariadic(Record[Idx++]);
-  BD->setBlockMissingReturnType(Record[Idx++]);
-  BD->setIsConversionFromLambda(Record[Idx++]);
+  BD->setIsVariadic(Record.readInt());
+  BD->setBlockMissingReturnType(Record.readInt());
+  BD->setIsConversionFromLambda(Record.readInt());
 
-  bool capturesCXXThis = Record[Idx++];
-  unsigned numCaptures = Record[Idx++];
+  bool capturesCXXThis = Record.readInt();
+  unsigned numCaptures = Record.readInt();
   SmallVector<BlockDecl::Capture, 16> captures;
   captures.reserve(numCaptures);
   for (unsigned i = 0; i != numCaptures; ++i) {
-    VarDecl *decl = ReadDeclAs<VarDecl>(Record, Idx);
-    unsigned flags = Record[Idx++];
+    VarDecl *decl = ReadDeclAs<VarDecl>();
+    unsigned flags = Record.readInt();
     bool byRef = (flags & 1);
     bool nested = (flags & 2);
-    Expr *copyExpr = ((flags & 4) ? Reader.ReadExpr(F) : nullptr);
+    Expr *copyExpr = ((flags & 4) ? Record.readExpr() : nullptr);
 
     captures.push_back(BlockDecl::Capture(decl, byRef, nested, copyExpr));
   }
@@ -1334,35 +1334,40 @@ void ASTDeclReader::VisitBlockDecl(BlockDecl *BD) {
 
 void ASTDeclReader::VisitCapturedDecl(CapturedDecl *CD) {
   VisitDecl(CD);
-  unsigned ContextParamPos = Record[Idx++];
-  CD->setNothrow(Record[Idx++] != 0);
+  unsigned ContextParamPos = Record.readInt();
+  CD->setNothrow(Record.readInt() != 0);
   // Body is set by VisitCapturedStmt.
   for (unsigned I = 0; I < CD->NumParams; ++I) {
     if (I != ContextParamPos)
-      CD->setParam(I, ReadDeclAs<ImplicitParamDecl>(Record, Idx));
+      CD->setParam(I, ReadDeclAs<ImplicitParamDecl>());
     else
-      CD->setContextParam(I, ReadDeclAs<ImplicitParamDecl>(Record, Idx));
+      CD->setContextParam(I, ReadDeclAs<ImplicitParamDecl>());
   }
 }
 
 void ASTDeclReader::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
   VisitDecl(D);
-  D->setLanguage((LinkageSpecDecl::LanguageIDs)Record[Idx++]);
-  D->setExternLoc(ReadSourceLocation(Record, Idx));
-  D->setRBraceLoc(ReadSourceLocation(Record, Idx));
+  D->setLanguage((LinkageSpecDecl::LanguageIDs)Record.readInt());
+  D->setExternLoc(ReadSourceLocation());
+  D->setRBraceLoc(ReadSourceLocation());
+}
+
+void ASTDeclReader::VisitExportDecl(ExportDecl *D) {
+  VisitDecl(D);
+  D->RBraceLoc = ReadSourceLocation();
 }
 
 void ASTDeclReader::VisitLabelDecl(LabelDecl *D) {
   VisitNamedDecl(D);
-  D->setLocStart(ReadSourceLocation(Record, Idx));
+  D->setLocStart(ReadSourceLocation());
 }
 
 void ASTDeclReader::VisitNamespaceDecl(NamespaceDecl *D) {
   RedeclarableResult Redecl = VisitRedeclarable(D);
   VisitNamedDecl(D);
-  D->setInline(Record[Idx++]);
-  D->LocStart = ReadSourceLocation(Record, Idx);
-  D->RBraceLoc = ReadSourceLocation(Record, Idx);
+  D->setInline(Record.readInt());
+  D->LocStart = ReadSourceLocation();
+  D->RBraceLoc = ReadSourceLocation();
 
   // Defer loading the anonymous namespace until we've finished merging
   // this namespace; loading it might load a later declaration of the
@@ -1370,7 +1375,7 @@ void ASTDeclReader::VisitNamespaceDecl(NamespaceDecl *D) {
   // get merged before newer ones try to merge.
   GlobalDeclID AnonNamespace = 0;
   if (Redecl.getFirstID() == ThisDeclID) {
-    AnonNamespace = ReadDeclID(Record, Idx);
+    AnonNamespace = ReadDeclID();
   } else {
     // Link this namespace back to the first declaration, which has already
     // been deserialized.
@@ -1384,7 +1389,7 @@ void ASTDeclReader::VisitNamespaceDecl(NamespaceDecl *D) {
     // any other module's anonymous namespaces, so don't attach the anonymous
     // namespace at all.
     NamespaceDecl *Anon = cast<NamespaceDecl>(Reader.GetDecl(AnonNamespace));
-    if (F.Kind != MK_ImplicitModule && F.Kind != MK_ExplicitModule)
+    if (!Record.isModule())
       D->setAnonymousNamespace(Anon);
   }
 }
@@ -1392,31 +1397,40 @@ void ASTDeclReader::VisitNamespaceDecl(NamespaceDecl *D) {
 void ASTDeclReader::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
   RedeclarableResult Redecl = VisitRedeclarable(D);
   VisitNamedDecl(D);
-  D->NamespaceLoc = ReadSourceLocation(Record, Idx);
-  D->IdentLoc = ReadSourceLocation(Record, Idx);
-  D->QualifierLoc = Reader.ReadNestedNameSpecifierLoc(F, Record, Idx);
-  D->Namespace = ReadDeclAs<NamedDecl>(Record, Idx);
+  D->NamespaceLoc = ReadSourceLocation();
+  D->IdentLoc = ReadSourceLocation();
+  D->QualifierLoc = Record.readNestedNameSpecifierLoc();
+  D->Namespace = ReadDeclAs<NamedDecl>();
   mergeRedeclarable(D, Redecl);
 }
 
 void ASTDeclReader::VisitUsingDecl(UsingDecl *D) {
   VisitNamedDecl(D);
-  D->setUsingLoc(ReadSourceLocation(Record, Idx));
-  D->QualifierLoc = Reader.ReadNestedNameSpecifierLoc(F, Record, Idx);
-  ReadDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record, Idx);
-  D->FirstUsingShadow.setPointer(ReadDeclAs<UsingShadowDecl>(Record, Idx));
-  D->setTypename(Record[Idx++]);
-  if (NamedDecl *Pattern = ReadDeclAs<NamedDecl>(Record, Idx))
+  D->setUsingLoc(ReadSourceLocation());
+  D->QualifierLoc = Record.readNestedNameSpecifierLoc();
+  ReadDeclarationNameLoc(D->DNLoc, D->getDeclName());
+  D->FirstUsingShadow.setPointer(ReadDeclAs<UsingShadowDecl>());
+  D->setTypename(Record.readInt());
+  if (NamedDecl *Pattern = ReadDeclAs<NamedDecl>())
     Reader.getContext().setInstantiatedFromUsingDecl(D, Pattern);
   mergeMergeable(D);
 }
 
+void ASTDeclReader::VisitUsingPackDecl(UsingPackDecl *D) {
+  VisitNamedDecl(D);
+  D->InstantiatedFrom = ReadDeclAs<NamedDecl>();
+  NamedDecl **Expansions = D->getTrailingObjects<NamedDecl*>();
+  for (unsigned I = 0; I != D->NumExpansions; ++I)
+    Expansions[I] = ReadDeclAs<NamedDecl>();
+  mergeMergeable(D);
+}
+
 void ASTDeclReader::VisitUsingShadowDecl(UsingShadowDecl *D) {
   RedeclarableResult Redecl = VisitRedeclarable(D);
   VisitNamedDecl(D);
-  D->setTargetDecl(ReadDeclAs<NamedDecl>(Record, Idx));
-  D->UsingOrNextShadow = ReadDeclAs<NamedDecl>(Record, Idx);
-  UsingShadowDecl *Pattern = ReadDeclAs<UsingShadowDecl>(Record, Idx);
+  D->setTargetDecl(ReadDeclAs<NamedDecl>());
+  D->UsingOrNextShadow = ReadDeclAs<NamedDecl>();
+  UsingShadowDecl *Pattern = ReadDeclAs<UsingShadowDecl>();
   if (Pattern)
     Reader.getContext().setInstantiatedFromUsingShadowDecl(D, Pattern);
   mergeRedeclarable(D, Redecl);
@@ -1425,115 +1439,114 @@ void ASTDeclReader::VisitUsingShadowDecl(UsingShadowDecl *D) {
 void ASTDeclReader::VisitConstructorUsingShadowDecl(
     ConstructorUsingShadowDecl *D) {
   VisitUsingShadowDecl(D);
-  D->NominatedBaseClassShadowDecl =
-      ReadDeclAs<ConstructorUsingShadowDecl>(Record, Idx);
-  D->ConstructedBaseClassShadowDecl =
-      ReadDeclAs<ConstructorUsingShadowDecl>(Record, Idx);
-  D->IsVirtual = Record[Idx++];
+  D->NominatedBaseClassShadowDecl = ReadDeclAs<ConstructorUsingShadowDecl>();
+  D->ConstructedBaseClassShadowDecl = ReadDeclAs<ConstructorUsingShadowDecl>();
+  D->IsVirtual = Record.readInt();
 }
 
 void ASTDeclReader::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
   VisitNamedDecl(D);
-  D->UsingLoc = ReadSourceLocation(Record, Idx);
-  D->NamespaceLoc = ReadSourceLocation(Record, Idx);
-  D->QualifierLoc = Reader.ReadNestedNameSpecifierLoc(F, Record, Idx);
-  D->NominatedNamespace = ReadDeclAs<NamedDecl>(Record, Idx);
-  D->CommonAncestor = ReadDeclAs<DeclContext>(Record, Idx);
+  D->UsingLoc = ReadSourceLocation();
+  D->NamespaceLoc = ReadSourceLocation();
+  D->QualifierLoc = Record.readNestedNameSpecifierLoc();
+  D->NominatedNamespace = ReadDeclAs<NamedDecl>();
+  D->CommonAncestor = ReadDeclAs<DeclContext>();
 }
 
 void ASTDeclReader::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
   VisitValueDecl(D);
-  D->setUsingLoc(ReadSourceLocation(Record, Idx));
-  D->QualifierLoc = Reader.ReadNestedNameSpecifierLoc(F, Record, Idx);
-  ReadDeclarationNameLoc(D->DNLoc, D->getDeclName(), Record, Idx);
+  D->setUsingLoc(ReadSourceLocation());
+  D->QualifierLoc = Record.readNestedNameSpecifierLoc();
+  ReadDeclarationNameLoc(D->DNLoc, D->getDeclName());
+  D->EllipsisLoc = ReadSourceLocation();
   mergeMergeable(D);
 }
 
 void ASTDeclReader::VisitUnresolvedUsingTypenameDecl(
                                                UnresolvedUsingTypenameDecl *D) {
   VisitTypeDecl(D);
-  D->TypenameLocation = ReadSourceLocation(Record, Idx);
-  D->QualifierLoc = Reader.ReadNestedNameSpecifierLoc(F, Record, Idx);
+  D->TypenameLocation = ReadSourceLocation();
+  D->QualifierLoc = Record.readNestedNameSpecifierLoc();
+  D->EllipsisLoc = ReadSourceLocation();
   mergeMergeable(D);
 }
 
 void ASTDeclReader::ReadCXXDefinitionData(
-                                   struct CXXRecordDecl::DefinitionData &Data,
-                                   const RecordData &Record, unsigned &Idx) {
+                                   struct CXXRecordDecl::DefinitionData &Data) {
   // Note: the caller has deserialized the IsLambda bit already.
-  Data.UserDeclaredConstructor = Record[Idx++];
-  Data.UserDeclaredSpecialMembers = Record[Idx++];
-  Data.Aggregate = Record[Idx++];
-  Data.PlainOldData = Record[Idx++];
-  Data.Empty = Record[Idx++];
-  Data.Polymorphic = Record[Idx++];
-  Data.Abstract = Record[Idx++];
-  Data.IsStandardLayout = Record[Idx++];
-  Data.HasNoNonEmptyBases = Record[Idx++];
-  Data.HasPrivateFields = Record[Idx++];
-  Data.HasProtectedFields = Record[Idx++];
-  Data.HasPublicFields = Record[Idx++];
-  Data.HasMutableFields = Record[Idx++];
-  Data.HasVariantMembers = Record[Idx++];
-  Data.HasOnlyCMembers = Record[Idx++];
-  Data.HasInClassInitializer = Record[Idx++];
-  Data.HasUninitializedReferenceMember = Record[Idx++];
-  Data.HasUninitializedFields = Record[Idx++];
-  Data.HasInheritedConstructor = Record[Idx++];
-  Data.HasInheritedAssignment = Record[Idx++];
-  Data.NeedOverloadResolutionForMoveConstructor = Record[Idx++];
-  Data.NeedOverloadResolutionForMoveAssignment = Record[Idx++];
-  Data.NeedOverloadResolutionForDestructor = Record[Idx++];
-  Data.DefaultedMoveConstructorIsDeleted = Record[Idx++];
-  Data.DefaultedMoveAssignmentIsDeleted = Record[Idx++];
-  Data.DefaultedDestructorIsDeleted = Record[Idx++];
-  Data.HasTrivialSpecialMembers = Record[Idx++];
-  Data.DeclaredNonTrivialSpecialMembers = Record[Idx++];
-  Data.HasIrrelevantDestructor = Record[Idx++];
-  Data.HasConstexprNonCopyMoveConstructor = Record[Idx++];
-  Data.HasDefaultedDefaultConstructor = Record[Idx++];
-  Data.DefaultedDefaultConstructorIsConstexpr = Record[Idx++];
-  Data.HasConstexprDefaultConstructor = Record[Idx++];
-  Data.HasNonLiteralTypeFieldsOrBases = Record[Idx++];
-  Data.ComputedVisibleConversions = Record[Idx++];
-  Data.UserProvidedDefaultConstructor = Record[Idx++];
-  Data.DeclaredSpecialMembers = Record[Idx++];
-  Data.ImplicitCopyConstructorHasConstParam = Record[Idx++];
-  Data.ImplicitCopyAssignmentHasConstParam = Record[Idx++];
-  Data.HasDeclaredCopyConstructorWithConstParam = Record[Idx++];
-  Data.HasDeclaredCopyAssignmentWithConstParam = Record[Idx++];
-
-  Data.NumBases = Record[Idx++];
+  Data.UserDeclaredConstructor = Record.readInt();
+  Data.UserDeclaredSpecialMembers = Record.readInt();
+  Data.Aggregate = Record.readInt();
+  Data.PlainOldData = Record.readInt();
+  Data.Empty = Record.readInt();
+  Data.Polymorphic = Record.readInt();
+  Data.Abstract = Record.readInt();
+  Data.IsStandardLayout = Record.readInt();
+  Data.HasNoNonEmptyBases = Record.readInt();
+  Data.HasPrivateFields = Record.readInt();
+  Data.HasProtectedFields = Record.readInt();
+  Data.HasPublicFields = Record.readInt();
+  Data.HasMutableFields = Record.readInt();
+  Data.HasVariantMembers = Record.readInt();
+  Data.HasOnlyCMembers = Record.readInt();
+  Data.HasInClassInitializer = Record.readInt();
+  Data.HasUninitializedReferenceMember = Record.readInt();
+  Data.HasUninitializedFields = Record.readInt();
+  Data.HasInheritedConstructor = Record.readInt();
+  Data.HasInheritedAssignment = Record.readInt();
+  Data.NeedOverloadResolutionForMoveConstructor = Record.readInt();
+  Data.NeedOverloadResolutionForMoveAssignment = Record.readInt();
+  Data.NeedOverloadResolutionForDestructor = Record.readInt();
+  Data.DefaultedMoveConstructorIsDeleted = Record.readInt();
+  Data.DefaultedMoveAssignmentIsDeleted = Record.readInt();
+  Data.DefaultedDestructorIsDeleted = Record.readInt();
+  Data.HasTrivialSpecialMembers = Record.readInt();
+  Data.DeclaredNonTrivialSpecialMembers = Record.readInt();
+  Data.HasIrrelevantDestructor = Record.readInt();
+  Data.HasConstexprNonCopyMoveConstructor = Record.readInt();
+  Data.HasDefaultedDefaultConstructor = Record.readInt();
+  Data.DefaultedDefaultConstructorIsConstexpr = Record.readInt();
+  Data.HasConstexprDefaultConstructor = Record.readInt();
+  Data.HasNonLiteralTypeFieldsOrBases = Record.readInt();
+  Data.ComputedVisibleConversions = Record.readInt();
+  Data.UserProvidedDefaultConstructor = Record.readInt();
+  Data.DeclaredSpecialMembers = Record.readInt();
+  Data.ImplicitCopyConstructorHasConstParam = Record.readInt();
+  Data.ImplicitCopyAssignmentHasConstParam = Record.readInt();
+  Data.HasDeclaredCopyConstructorWithConstParam = Record.readInt();
+  Data.HasDeclaredCopyAssignmentWithConstParam = Record.readInt();
+
+  Data.NumBases = Record.readInt();
   if (Data.NumBases)
-    Data.Bases = ReadGlobalOffset(F, Record, Idx);
-  Data.NumVBases = Record[Idx++];
+    Data.Bases = ReadGlobalOffset();
+  Data.NumVBases = Record.readInt();
   if (Data.NumVBases)
-    Data.VBases = ReadGlobalOffset(F, Record, Idx);
-  
-  Reader.ReadUnresolvedSet(F, Data.Conversions, Record, Idx);
-  Reader.ReadUnresolvedSet(F, Data.VisibleConversions, Record, Idx);
+    Data.VBases = ReadGlobalOffset();
+
+  Record.readUnresolvedSet(Data.Conversions);
+  Record.readUnresolvedSet(Data.VisibleConversions);
   assert(Data.Definition && "Data.Definition should be already set!");
-  Data.FirstFriend = ReadDeclID(Record, Idx);
+  Data.FirstFriend = ReadDeclID();
 
   if (Data.IsLambda) {
     typedef LambdaCapture Capture;
     CXXRecordDecl::LambdaDefinitionData &Lambda
       = static_cast<CXXRecordDecl::LambdaDefinitionData &>(Data);
-    Lambda.Dependent = Record[Idx++];
-    Lambda.IsGenericLambda = Record[Idx++];
-    Lambda.CaptureDefault = Record[Idx++];
-    Lambda.NumCaptures = Record[Idx++];
-    Lambda.NumExplicitCaptures = Record[Idx++];
-    Lambda.ManglingNumber = Record[Idx++];
-    Lambda.ContextDecl = ReadDecl(Record, Idx);
+    Lambda.Dependent = Record.readInt();
+    Lambda.IsGenericLambda = Record.readInt();
+    Lambda.CaptureDefault = Record.readInt();
+    Lambda.NumCaptures = Record.readInt();
+    Lambda.NumExplicitCaptures = Record.readInt();
+    Lambda.ManglingNumber = Record.readInt();
+    Lambda.ContextDecl = ReadDeclID();
     Lambda.Captures 
       = (Capture*)Reader.Context.Allocate(sizeof(Capture)*Lambda.NumCaptures);
     Capture *ToCapture = Lambda.Captures;
-    Lambda.MethodTyInfo = GetTypeSourceInfo(Record, Idx);
+    Lambda.MethodTyInfo = GetTypeSourceInfo();
     for (unsigned I = 0, N = Lambda.NumCaptures; I != N; ++I) {
-      SourceLocation Loc = ReadSourceLocation(Record, Idx);
-      bool IsImplicit = Record[Idx++];
-      LambdaCaptureKind Kind = static_cast<LambdaCaptureKind>(Record[Idx++]);
+      SourceLocation Loc = ReadSourceLocation();
+      bool IsImplicit = Record.readInt();
+      LambdaCaptureKind Kind = static_cast<LambdaCaptureKind>(Record.readInt());
       switch (Kind) {
       case LCK_StarThis: 
       case LCK_This:
@@ -1542,8 +1555,8 @@ void ASTDeclReader::ReadCXXDefinitionData(
         break;
       case LCK_ByCopy:
       case LCK_ByRef:
-        VarDecl *Var = ReadDeclAs<VarDecl>(Record, Idx);
-        SourceLocation EllipsisLoc = ReadSourceLocation(Record, Idx);
+        VarDecl *Var = ReadDeclAs<VarDecl>();
+        SourceLocation EllipsisLoc = ReadSourceLocation();
         *ToCapture++ = Capture(Loc, IsImplicit, Kind, Var, EllipsisLoc);
         break;
       }
@@ -1563,7 +1576,7 @@ void ASTDeclReader::MergeDefinitionData(
                                                     DD.Definition));
     Reader.PendingDefinitions.erase(MergeDD.Definition);
     MergeDD.Definition->IsCompleteDefinition = false;
-    mergeDefinitionVisibility(DD.Definition, MergeDD.Definition);
+    Reader.mergeDefinitionVisibility(DD.Definition, MergeDD.Definition);
     assert(Reader.Lookups.find(MergeDD.Definition) == Reader.Lookups.end() &&
            "already loaded pending lookups for merged definition");
   }
@@ -1665,14 +1678,14 @@ void ASTDeclReader::ReadCXXRecordDefinition(CXXRecordDecl *D, bool Update) {
 
   // Determine whether this is a lambda closure type, so that we can
   // allocate the appropriate DefinitionData structure.
-  bool IsLambda = Record[Idx++];
+  bool IsLambda = Record.readInt();
   if (IsLambda)
     DD = new (C) CXXRecordDecl::LambdaDefinitionData(D, nullptr, false, false,
                                                      LCD_None);
   else
     DD = new (C) struct CXXRecordDecl::DefinitionData(D);
 
-  ReadCXXDefinitionData(*DD, Record, Idx);
+  ReadCXXDefinitionData(*DD);
 
   // We might already have a definition for this record. This can happen either
   // because we're reading an update record, or because we've already done some
@@ -1706,7 +1719,7 @@ ASTDeclReader::VisitCXXRecordDeclImpl(CXXRecordDecl *D) {
   enum CXXRecKind {
     CXXRecNotTemplate = 0, CXXRecTemplate, CXXRecMemberSpecialization
   };
-  switch ((CXXRecKind)Record[Idx++]) {
+  switch ((CXXRecKind)Record.readInt()) {
   case CXXRecNotTemplate:
     // Merged when we merge the folding set entry in the primary template.
     if (!isa<ClassTemplateSpecializationDecl>(D))
@@ -1714,7 +1727,7 @@ ASTDeclReader::VisitCXXRecordDeclImpl(CXXRecordDecl *D) {
     break;
   case CXXRecTemplate: {
     // Merged when we merge the template.
-    ClassTemplateDecl *Template = ReadDeclAs<ClassTemplateDecl>(Record, Idx);
+    ClassTemplateDecl *Template = ReadDeclAs<ClassTemplateDecl>();
     D->TemplateOrInstantiation = Template;
     if (!Template->getTemplatedDecl()) {
       // We've not actually loaded the ClassTemplateDecl yet, because we're
@@ -1728,9 +1741,10 @@ ASTDeclReader::VisitCXXRecordDeclImpl(CXXRecordDecl *D) {
     break;
   }
   case CXXRecMemberSpecialization: {
-    CXXRecordDecl *RD = ReadDeclAs<CXXRecordDecl>(Record, Idx);
-    TemplateSpecializationKind TSK = (TemplateSpecializationKind)Record[Idx++];
-    SourceLocation POI = ReadSourceLocation(Record, Idx);
+    CXXRecordDecl *RD = ReadDeclAs<CXXRecordDecl>();
+    TemplateSpecializationKind TSK =
+        (TemplateSpecializationKind)Record.readInt();
+    SourceLocation POI = ReadSourceLocation();
     MemberSpecializationInfo *MSI = new (C) MemberSpecializationInfo(RD, TSK);
     MSI->setPointOfInstantiation(POI);
     D->TemplateOrInstantiation = MSI;
@@ -1739,7 +1753,7 @@ ASTDeclReader::VisitCXXRecordDeclImpl(CXXRecordDecl *D) {
   }
   }
 
-  bool WasDefinition = Record[Idx++];
+  bool WasDefinition = Record.readInt();
   if (WasDefinition)
     ReadCXXRecordDefinition(D, /*Update*/false);
   else
@@ -1749,7 +1763,7 @@ ASTDeclReader::VisitCXXRecordDeclImpl(CXXRecordDecl *D) {
   // Lazily load the key function to avoid deserializing every method so we can
   // compute it.
   if (WasDefinition) {
-    DeclID KeyFn = ReadDeclID(Record, Idx);
+    DeclID KeyFn = ReadDeclID();
     if (KeyFn && D->IsCompleteDefinition)
       // FIXME: This is wrong for the ARM ABI, where some other module may have
       // made this function no longer be a key function. We need an update
@@ -1763,18 +1777,18 @@ ASTDeclReader::VisitCXXRecordDeclImpl(CXXRecordDecl *D) {
 void ASTDeclReader::VisitCXXMethodDecl(CXXMethodDecl *D) {
   VisitFunctionDecl(D);
 
-  unsigned NumOverridenMethods = Record[Idx++];
+  unsigned NumOverridenMethods = Record.readInt();
   if (D->isCanonicalDecl()) {
     while (NumOverridenMethods--) {
       // Avoid invariant checking of CXXMethodDecl::addOverriddenMethod,
       // MD may be initializing.
-      if (CXXMethodDecl *MD = ReadDeclAs<CXXMethodDecl>(Record, Idx))
+      if (CXXMethodDecl *MD = ReadDeclAs<CXXMethodDecl>())
         Reader.getContext().addOverriddenMethod(D, MD->getCanonicalDecl());
     }
   } else {
     // We don't care about which declarations this used to override; we get
     // the relevant information from the canonical declaration.
-    Idx += NumOverridenMethods;
+    Record.skipInts(NumOverridenMethods);
   }
 }
 
@@ -1782,21 +1796,21 @@ void ASTDeclReader::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
   // We need the inherited constructor information to merge the declaration,
   // so we have to read it before we call VisitCXXMethodDecl.
   if (D->isInheritingConstructor()) {
-    auto *Shadow = ReadDeclAs<ConstructorUsingShadowDecl>(Record, Idx);
-    auto *Ctor = ReadDeclAs<CXXConstructorDecl>(Record, Idx);
+    auto *Shadow = ReadDeclAs<ConstructorUsingShadowDecl>();
+    auto *Ctor = ReadDeclAs<CXXConstructorDecl>();
     *D->getTrailingObjects<InheritedConstructor>() =
         InheritedConstructor(Shadow, Ctor);
   }
 
   VisitCXXMethodDecl(D);
 
-  D->IsExplicitSpecified = Record[Idx++];
+  D->IsExplicitSpecified = Record.readInt();
 }
 
 void ASTDeclReader::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
   VisitCXXMethodDecl(D);
 
-  if (auto *OperatorDelete = ReadDeclAs<FunctionDecl>(Record, Idx)) {
+  if (auto *OperatorDelete = ReadDeclAs<FunctionDecl>()) {
     auto *Canon = cast<CXXDestructorDecl>(D->getCanonicalDecl());
     // FIXME: Check consistency if we have an old and new operator delete.
     if (!Canon->OperatorDelete)
@@ -1806,65 +1820,64 @@ void ASTDeclReader::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
 
 void ASTDeclReader::VisitCXXConversionDecl(CXXConversionDecl *D) {
   VisitCXXMethodDecl(D);
-  D->IsExplicitSpecified = Record[Idx++];
+  D->IsExplicitSpecified = Record.readInt();
 }
 
 void ASTDeclReader::VisitImportDecl(ImportDecl *D) {
   VisitDecl(D);
-  D->ImportedAndComplete.setPointer(readModule(Record, Idx));
-  D->ImportedAndComplete.setInt(Record[Idx++]);
+  D->ImportedAndComplete.setPointer(readModule());
+  D->ImportedAndComplete.setInt(Record.readInt());
   SourceLocation *StoredLocs = D->getTrailingObjects<SourceLocation>();
   for (unsigned I = 0, N = Record.back(); I != N; ++I)
-    StoredLocs[I] = ReadSourceLocation(Record, Idx);
-  ++Idx; // The number of stored source locations.
+    StoredLocs[I] = ReadSourceLocation();
+  (void)Record.readInt(); // The number of stored source locations.
 }
 
 void ASTDeclReader::VisitAccessSpecDecl(AccessSpecDecl *D) {
   VisitDecl(D);
-  D->setColonLoc(ReadSourceLocation(Record, Idx));
+  D->setColonLoc(ReadSourceLocation());
 }
 
 void ASTDeclReader::VisitFriendDecl(FriendDecl *D) {
   VisitDecl(D);
-  if (Record[Idx++]) // hasFriendDecl
-    D->Friend = ReadDeclAs<NamedDecl>(Record, Idx);
+  if (Record.readInt()) // hasFriendDecl
+    D->Friend = ReadDeclAs<NamedDecl>();
   else
-    D->Friend = GetTypeSourceInfo(Record, Idx);
+    D->Friend = GetTypeSourceInfo();
   for (unsigned i = 0; i != D->NumTPLists; ++i)
     D->getTrailingObjects<TemplateParameterList *>()[i] =
-        Reader.ReadTemplateParameterList(F, Record, Idx);
-  D->NextFriend = ReadDeclID(Record, Idx);
-  D->UnsupportedFriend = (Record[Idx++] != 0);
-  D->FriendLoc = ReadSourceLocation(Record, Idx);
+        Record.readTemplateParameterList();
+  D->NextFriend = ReadDeclID();
+  D->UnsupportedFriend = (Record.readInt() != 0);
+  D->FriendLoc = ReadSourceLocation();
 }
 
 void ASTDeclReader::VisitFriendTemplateDecl(FriendTemplateDecl *D) {
   VisitDecl(D);
-  unsigned NumParams = Record[Idx++];
+  unsigned NumParams = Record.readInt();
   D->NumParams = NumParams;
   D->Params = new TemplateParameterList*[NumParams];
   for (unsigned i = 0; i != NumParams; ++i)
-    D->Params[i] = Reader.ReadTemplateParameterList(F, Record, Idx);
-  if (Record[Idx++]) // HasFriendDecl
-    D->Friend = ReadDeclAs<NamedDecl>(Record, Idx);
+    D->Params[i] = Record.readTemplateParameterList();
+  if (Record.readInt()) // HasFriendDecl
+    D->Friend = ReadDeclAs<NamedDecl>();
   else
-    D->Friend = GetTypeSourceInfo(Record, Idx);
-  D->FriendLoc = ReadSourceLocation(Record, Idx);
+    D->Friend = GetTypeSourceInfo();
+  D->FriendLoc = ReadSourceLocation();
 }
 
 DeclID ASTDeclReader::VisitTemplateDecl(TemplateDecl *D) {
   VisitNamedDecl(D);
 
-  DeclID PatternID = ReadDeclID(Record, Idx);
+  DeclID PatternID = ReadDeclID();
   NamedDecl *TemplatedDecl = cast_or_null<NamedDecl>(Reader.GetDecl(PatternID));
-  TemplateParameterList* TemplateParams
-      = Reader.ReadTemplateParameterList(F, Record, Idx); 
+  TemplateParameterList *TemplateParams = Record.readTemplateParameterList();
   D->init(TemplatedDecl, TemplateParams);
 
   return PatternID;
 }
 
-ASTDeclReader::RedeclarableResult 
+ASTDeclReader::RedeclarableResult
 ASTDeclReader::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
   RedeclarableResult Redecl = VisitRedeclarable(D);
 
@@ -1881,17 +1894,17 @@ ASTDeclReader::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
   // for the 'common' pointer.
   if (ThisDeclID == Redecl.getFirstID()) {
     if (RedeclarableTemplateDecl *RTD
-          = ReadDeclAs<RedeclarableTemplateDecl>(Record, Idx)) {
+          = ReadDeclAs<RedeclarableTemplateDecl>()) {
       assert(RTD->getKind() == D->getKind() &&
              "InstantiatedFromMemberTemplate kind mismatch");
       D->setInstantiatedFromMemberTemplate(RTD);
-      if (Record[Idx++])
+      if (Record.readInt())
         D->setMemberSpecialization();
     }
   }
 
   DeclID PatternID = VisitTemplateDecl(D);
-  D->IdentifierNamespace = Record[Idx++];
+  D->IdentifierNamespace = Record.readInt();
 
   mergeRedeclarable(D, Redecl, PatternID);
 
@@ -1971,14 +1984,14 @@ ASTDeclReader::RedeclarableResult
 ASTDeclReader::VisitClassTemplateSpecializationDeclImpl(
     ClassTemplateSpecializationDecl *D) {
   RedeclarableResult Redecl = VisitCXXRecordDeclImpl(D);
-  
+
   ASTContext &C = Reader.getContext();
-  if (Decl *InstD = ReadDecl(Record, Idx)) {
+  if (Decl *InstD = ReadDecl()) {
     if (ClassTemplateDecl *CTD = dyn_cast<ClassTemplateDecl>(InstD)) {
       D->SpecializedTemplate = CTD;
     } else {
       SmallVector<TemplateArgument, 8> TemplArgs;
-      Reader.ReadTemplateArgumentList(TemplArgs, F, Record, Idx);
+      Record.readTemplateArgumentList(TemplArgs);
       TemplateArgumentList *ArgList
         = TemplateArgumentList::CreateCopy(C, TemplArgs);
       ClassTemplateSpecializationDecl::SpecializedPartialSpecialization *PS
@@ -1992,15 +2005,14 @@ ASTDeclReader::VisitClassTemplateSpecializationDeclImpl(
   }
 
   SmallVector<TemplateArgument, 8> TemplArgs;
-  Reader.ReadTemplateArgumentList(TemplArgs, F, Record, Idx,
-                                  /*Canonicalize*/ true);
+  Record.readTemplateArgumentList(TemplArgs, /*Canonicalize*/ true);
   D->TemplateArgs = TemplateArgumentList::CreateCopy(C, TemplArgs);
-  D->PointOfInstantiation = ReadSourceLocation(Record, Idx);
-  D->SpecializationKind = (TemplateSpecializationKind)Record[Idx++];
+  D->PointOfInstantiation = ReadSourceLocation();
+  D->SpecializationKind = (TemplateSpecializationKind)Record.readInt();
 
-  bool writtenAsCanonicalDecl = Record[Idx++];
+  bool writtenAsCanonicalDecl = Record.readInt();
   if (writtenAsCanonicalDecl) {
-    ClassTemplateDecl *CanonPattern = ReadDeclAs<ClassTemplateDecl>(Record,Idx);
+    ClassTemplateDecl *CanonPattern = ReadDeclAs<ClassTemplateDecl>();
     if (D->isCanonicalDecl()) { // It's kept in the folding set.
       // Set this as, or find, the canonical declaration for this specialization
       ClassTemplateSpecializationDecl *CanonSpec;
@@ -2030,12 +2042,12 @@ ASTDeclReader::VisitClassTemplateSpecializationDeclImpl(
   }
 
   // Explicit info.
-  if (TypeSourceInfo *TyInfo = GetTypeSourceInfo(Record, Idx)) {
+  if (TypeSourceInfo *TyInfo = GetTypeSourceInfo()) {
     ClassTemplateSpecializationDecl::ExplicitSpecializationInfo *ExplicitInfo
         = new (C) ClassTemplateSpecializationDecl::ExplicitSpecializationInfo;
     ExplicitInfo->TypeAsWritten = TyInfo;
-    ExplicitInfo->ExternLoc = ReadSourceLocation(Record, Idx);
-    ExplicitInfo->TemplateKeywordLoc = ReadSourceLocation(Record, Idx);
+    ExplicitInfo->ExternLoc = ReadSourceLocation();
+    ExplicitInfo->TemplateKeywordLoc = ReadSourceLocation();
     D->ExplicitInfo = ExplicitInfo;
   }
 
@@ -2046,21 +2058,21 @@ void ASTDeclReader::VisitClassTemplatePartialSpecializationDecl(
                                     ClassTemplatePartialSpecializationDecl *D) {
   RedeclarableResult Redecl = VisitClassTemplateSpecializationDeclImpl(D);
 
-  D->TemplateParams = Reader.ReadTemplateParameterList(F, Record, Idx);
-  D->ArgsAsWritten = Reader.ReadASTTemplateArgumentListInfo(F, Record, Idx);
+  D->TemplateParams = Record.readTemplateParameterList();
+  D->ArgsAsWritten = Record.readASTTemplateArgumentListInfo();
 
   // These are read/set from/to the first declaration.
   if (ThisDeclID == Redecl.getFirstID()) {
     D->InstantiatedFromMember.setPointer(
-      ReadDeclAs<ClassTemplatePartialSpecializationDecl>(Record, Idx));
-    D->InstantiatedFromMember.setInt(Record[Idx++]);
+      ReadDeclAs<ClassTemplatePartialSpecializationDecl>());
+    D->InstantiatedFromMember.setInt(Record.readInt());
   }
 }
 
 void ASTDeclReader::VisitClassScopeFunctionSpecializationDecl(
                                     ClassScopeFunctionSpecializationDecl *D) {
   VisitDecl(D);
-  D->Specialization = ReadDeclAs<CXXMethodDecl>(Record, Idx);
+  D->Specialization = ReadDeclAs<CXXMethodDecl>();
 }
 
 void ASTDeclReader::VisitFunctionTemplateDecl(FunctionTemplateDecl *D) {
@@ -2090,12 +2102,12 @@ ASTDeclReader::VisitVarTemplateSpecializationDeclImpl(
   RedeclarableResult Redecl = VisitVarDeclImpl(D);
 
   ASTContext &C = Reader.getContext();
-  if (Decl *InstD = ReadDecl(Record, Idx)) {
+  if (Decl *InstD = ReadDecl()) {
     if (VarTemplateDecl *VTD = dyn_cast<VarTemplateDecl>(InstD)) {
       D->SpecializedTemplate = VTD;
     } else {
       SmallVector<TemplateArgument, 8> TemplArgs;
-      Reader.ReadTemplateArgumentList(TemplArgs, F, Record, Idx);
+      Record.readTemplateArgumentList(TemplArgs);
       TemplateArgumentList *ArgList = TemplateArgumentList::CreateCopy(
           C, TemplArgs);
       VarTemplateSpecializationDecl::SpecializedPartialSpecialization *PS =
@@ -2109,25 +2121,24 @@ ASTDeclReader::VisitVarTemplateSpecializationDeclImpl(
   }
 
   // Explicit info.
-  if (TypeSourceInfo *TyInfo = GetTypeSourceInfo(Record, Idx)) {
+  if (TypeSourceInfo *TyInfo = GetTypeSourceInfo()) {
     VarTemplateSpecializationDecl::ExplicitSpecializationInfo *ExplicitInfo =
         new (C) VarTemplateSpecializationDecl::ExplicitSpecializationInfo;
     ExplicitInfo->TypeAsWritten = TyInfo;
-    ExplicitInfo->ExternLoc = ReadSourceLocation(Record, Idx);
-    ExplicitInfo->TemplateKeywordLoc = ReadSourceLocation(Record, Idx);
+    ExplicitInfo->ExternLoc = ReadSourceLocation();
+    ExplicitInfo->TemplateKeywordLoc = ReadSourceLocation();
     D->ExplicitInfo = ExplicitInfo;
   }
 
   SmallVector<TemplateArgument, 8> TemplArgs;
-  Reader.ReadTemplateArgumentList(TemplArgs, F, Record, Idx,
-                                  /*Canonicalize*/ true);
+  Record.readTemplateArgumentList(TemplArgs, /*Canonicalize*/ true);
   D->TemplateArgs = TemplateArgumentList::CreateCopy(C, TemplArgs);
-  D->PointOfInstantiation = ReadSourceLocation(Record, Idx);
-  D->SpecializationKind = (TemplateSpecializationKind)Record[Idx++];
+  D->PointOfInstantiation = ReadSourceLocation();
+  D->SpecializationKind = (TemplateSpecializationKind)Record.readInt();
 
-  bool writtenAsCanonicalDecl = Record[Idx++];
+  bool writtenAsCanonicalDecl = Record.readInt();
   if (writtenAsCanonicalDecl) {
-    VarTemplateDecl *CanonPattern = ReadDeclAs<VarTemplateDecl>(Record, Idx);
+    VarTemplateDecl *CanonPattern = ReadDeclAs<VarTemplateDecl>();
     if (D->isCanonicalDecl()) { // It's kept in the folding set.
       // FIXME: If it's already present, merge it.
       if (VarTemplatePartialSpecializationDecl *Partial =
@@ -2152,63 +2163,63 @@ void ASTDeclReader::VisitVarTemplatePartialSpecializationDecl(
     VarTemplatePartialSpecializationDecl *D) {
   RedeclarableResult Redecl = VisitVarTemplateSpecializationDeclImpl(D);
 
-  D->TemplateParams = Reader.ReadTemplateParameterList(F, Record, Idx);
-  D->ArgsAsWritten = Reader.ReadASTTemplateArgumentListInfo(F, Record, Idx);
+  D->TemplateParams = Record.readTemplateParameterList();
+  D->ArgsAsWritten = Record.readASTTemplateArgumentListInfo();
 
   // These are read/set from/to the first declaration.
   if (ThisDeclID == Redecl.getFirstID()) {
     D->InstantiatedFromMember.setPointer(
-        ReadDeclAs<VarTemplatePartialSpecializationDecl>(Record, Idx));
-    D->InstantiatedFromMember.setInt(Record[Idx++]);
+        ReadDeclAs<VarTemplatePartialSpecializationDecl>());
+    D->InstantiatedFromMember.setInt(Record.readInt());
   }
 }
 
 void ASTDeclReader::VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D) {
   VisitTypeDecl(D);
 
-  D->setDeclaredWithTypename(Record[Idx++]);
+  D->setDeclaredWithTypename(Record.readInt());
 
-  if (Record[Idx++])
-    D->setDefaultArgument(GetTypeSourceInfo(Record, Idx));
+  if (Record.readInt())
+    D->setDefaultArgument(GetTypeSourceInfo());
 }
 
 void ASTDeclReader::VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D) {
   VisitDeclaratorDecl(D);
   // TemplateParmPosition.
-  D->setDepth(Record[Idx++]);
-  D->setPosition(Record[Idx++]);
+  D->setDepth(Record.readInt());
+  D->setPosition(Record.readInt());
   if (D->isExpandedParameterPack()) {
     auto TypesAndInfos =
         D->getTrailingObjects<std::pair<QualType, TypeSourceInfo *>>();
     for (unsigned I = 0, N = D->getNumExpansionTypes(); I != N; ++I) {
-      new (&TypesAndInfos[I].first) QualType(Reader.readType(F, Record, Idx));
-      TypesAndInfos[I].second = GetTypeSourceInfo(Record, Idx);
+      new (&TypesAndInfos[I].first) QualType(Record.readType());
+      TypesAndInfos[I].second = GetTypeSourceInfo();
     }
   } else {
     // Rest of NonTypeTemplateParmDecl.
-    D->ParameterPack = Record[Idx++];
-    if (Record[Idx++])
-      D->setDefaultArgument(Reader.ReadExpr(F));
+    D->ParameterPack = Record.readInt();
+    if (Record.readInt())
+      D->setDefaultArgument(Record.readExpr());
   }
 }
 
 void ASTDeclReader::VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D) {
   VisitTemplateDecl(D);
   // TemplateParmPosition.
-  D->setDepth(Record[Idx++]);
-  D->setPosition(Record[Idx++]);
+  D->setDepth(Record.readInt());
+  D->setPosition(Record.readInt());
   if (D->isExpandedParameterPack()) {
     TemplateParameterList **Data =
         D->getTrailingObjects<TemplateParameterList *>();
     for (unsigned I = 0, N = D->getNumExpansionTemplateParameters();
          I != N; ++I)
-      Data[I] = Reader.ReadTemplateParameterList(F, Record, Idx);
+      Data[I] = Record.readTemplateParameterList();
   } else {
     // Rest of TemplateTemplateParmDecl.
-    D->ParameterPack = Record[Idx++];
-    if (Record[Idx++])
+    D->ParameterPack = Record.readInt();
+    if (Record.readInt())
       D->setDefaultArgument(Reader.getContext(),
-                            Reader.ReadTemplateArgumentLoc(F, Record, Idx));
+                            Record.readTemplateArgumentLoc());
   }
 }
 
@@ -2218,10 +2229,10 @@ void ASTDeclReader::VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D) {
 
 void ASTDeclReader::VisitStaticAssertDecl(StaticAssertDecl *D) {
   VisitDecl(D);
-  D->AssertExprAndFailed.setPointer(Reader.ReadExpr(F));
-  D->AssertExprAndFailed.setInt(Record[Idx++]);
-  D->Message = cast_or_null<StringLiteral>(Reader.ReadExpr(F));
-  D->RParenLoc = ReadSourceLocation(Record, Idx);
+  D->AssertExprAndFailed.setPointer(Record.readExpr());
+  D->AssertExprAndFailed.setInt(Record.readInt());
+  D->Message = cast_or_null<StringLiteral>(Record.readExpr());
+  D->RParenLoc = ReadSourceLocation();
 }
 
 void ASTDeclReader::VisitEmptyDecl(EmptyDecl *D) {
@@ -2230,15 +2241,15 @@ void ASTDeclReader::VisitEmptyDecl(EmptyDecl *D) {
 
 std::pair<uint64_t, uint64_t>
 ASTDeclReader::VisitDeclContext(DeclContext *DC) {
-  uint64_t LexicalOffset = ReadLocalOffset(Record, Idx);
-  uint64_t VisibleOffset = ReadLocalOffset(Record, Idx);
+  uint64_t LexicalOffset = ReadLocalOffset();
+  uint64_t VisibleOffset = ReadLocalOffset();
   return std::make_pair(LexicalOffset, VisibleOffset);
 }
 
 template <typename T>
 ASTDeclReader::RedeclarableResult
 ASTDeclReader::VisitRedeclarable(Redeclarable<T> *D) {
-  DeclID FirstDeclID = ReadDeclID(Record, Idx);
+  DeclID FirstDeclID = ReadDeclID();
   Decl *MergeWith = nullptr;
 
   bool IsKeyDecl = ThisDeclID == FirstDeclID;
@@ -2252,7 +2263,7 @@ ASTDeclReader::VisitRedeclarable(Redeclarable<T> *D) {
     FirstDeclID = ThisDeclID;
     IsKeyDecl = true;
     IsFirstLocalDecl = true;
-  } else if (unsigned N = Record[Idx++]) {
+  } else if (unsigned N = Record.readInt()) {
     // This declaration was the first local declaration, but may have imported
     // other declarations.
     IsKeyDecl = N == 1;
@@ -2264,13 +2275,13 @@ ASTDeclReader::VisitRedeclarable(Redeclarable<T> *D) {
     // FIXME: Provide a known merge target to the second and subsequent such
     // declaration.
     for (unsigned I = 0; I != N - 1; ++I)
-      MergeWith = ReadDecl(Record, Idx/*, MergeWith*/);
+      MergeWith = ReadDecl();
 
-    RedeclOffset = ReadLocalOffset(Record, Idx);
+    RedeclOffset = ReadLocalOffset();
   } else {
     // This declaration was not the first local declaration. Read the first
     // local declaration now, to trigger the import of other redeclarations.
-    (void)ReadDecl(Record, Idx);
+    (void)ReadDecl();
   }
 
   T *FirstDecl = cast_or_null<T>(Reader.GetDecl(FirstDeclID));
@@ -2281,7 +2292,7 @@ ASTDeclReader::VisitRedeclarable(Redeclarable<T> *D) {
     // loaded & attached later on.
     D->RedeclLink = Redeclarable<T>::PreviousDeclLink(FirstDecl);
     D->First = FirstDecl->getCanonicalDecl();
-  }    
+  }
 
   T *DAsT = static_cast<T*>(D);
 
@@ -2292,7 +2303,7 @@ ASTDeclReader::VisitRedeclarable(Redeclarable<T> *D) {
   if (IsFirstLocalDecl)
     Reader.PendingDeclChains.push_back(std::make_pair(DAsT, RedeclOffset));
 
-  return RedeclarableResult(FirstDeclID, MergeWith, IsKeyDecl);
+  return RedeclarableResult(MergeWith, FirstDeclID, IsKeyDecl);
 }
 
 /// \brief Attempts to merge the given declaration (D) with another declaration
@@ -2301,8 +2312,6 @@ template<typename T>
 void ASTDeclReader::mergeRedeclarable(Redeclarable<T> *DBase,
                                       RedeclarableResult &Redecl,
                                       DeclID TemplatePatternID) {
-  T *D = static_cast<T*>(DBase);
-
   // If modules are not available, there is no reason to perform this merge.
   if (!Reader.getContext().getLangOpts().Modules)
     return;
@@ -2311,6 +2320,8 @@ void ASTDeclReader::mergeRedeclarable(Redeclarable<T> *DBase,
   if (!DBase->isFirstDecl())
     return;
 
+  T *D = static_cast<T*>(DBase);
+
   if (auto *Existing = Redecl.getKnownMergeTarget())
     // We already know of an existing declaration we should merge with.
     mergeRedeclarable(D, cast<T>(Existing), Redecl, TemplatePatternID);
@@ -2334,8 +2345,9 @@ void ASTDeclReader::mergeTemplatePattern(RedeclarableTemplateDecl *D,
                                          DeclID DsID, bool IsKeyDecl) {
   auto *DPattern = D->getTemplatedDecl();
   auto *ExistingPattern = Existing->getTemplatedDecl();
-  RedeclarableResult Result(DPattern->getCanonicalDecl()->getGlobalID(),
-                            /*MergeWith*/ ExistingPattern, IsKeyDecl);
+  RedeclarableResult Result(/*MergeWith*/ ExistingPattern,
+                            DPattern->getCanonicalDecl()->getGlobalID(),
+                            IsKeyDecl);
 
   if (auto *DClass = dyn_cast<CXXRecordDecl>(DPattern)) {
     // Merge with any existing definition.
@@ -2436,17 +2448,17 @@ void ASTDeclReader::VisitOMPThreadPrivateDecl(OMPThreadPrivateDecl *D) {
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i) {
-    Vars.push_back(Reader.ReadExpr(F));
+    Vars.push_back(Record.readExpr());
   }
   D->setVars(Vars);
 }
 
 void ASTDeclReader::VisitOMPDeclareReductionDecl(OMPDeclareReductionDecl *D) {
   VisitValueDecl(D);
-  D->setLocation(Reader.ReadSourceLocation(F, Record, Idx));
-  D->setCombiner(Reader.ReadExpr(F));
-  D->setInitializer(Reader.ReadExpr(F));
-  D->PrevDeclInScope = Reader.ReadDeclID(F, Record, Idx);
+  D->setLocation(ReadSourceLocation());
+  D->setCombiner(Record.readExpr());
+  D->setInitializer(Record.readExpr());
+  D->PrevDeclInScope = ReadDeclID();
 }
 
 void ASTDeclReader::VisitOMPCapturedExprDecl(OMPCapturedExprDecl *D) {
@@ -2494,10 +2506,16 @@ inline void ASTReader::LoadedDecl(unsigned Index, Decl *D) {
 /// This routine should return true for anything that might affect
 /// code generation, e.g., inline function definitions, Objective-C
 /// declarations with metadata, etc.
-static bool isConsumerInterestedIn(Decl *D, bool HasBody) {
+static bool isConsumerInterestedIn(ASTContext &Ctx, Decl *D, bool HasBody) {
   // An ObjCMethodDecl is never considered as "interesting" because its
   // implementation container always is.
 
+  // An ImportDecl or VarDecl imported from a module will get emitted when
+  // we import the relevant module.
+  if ((isa<ImportDecl>(D) || isa<VarDecl>(D)) && Ctx.DeclMustBeEmitted(D) &&
+      D->getImportedOwningModule())
+    return false;
+
   if (isa<FileScopeAsmDecl>(D) || 
       isa<ObjCProtocolDecl>(D) || 
       isa<ObjCImplDecl>(D) ||
@@ -2867,7 +2885,7 @@ static NamedDecl *getDeclForMerging(NamedDecl *Found,
     return nullptr;
 
   if (auto *TND = dyn_cast<TypedefNameDecl>(Found))
-    return TND->getAnonDeclWithTypedefName();
+    return TND->getAnonDeclWithTypedefName(/*AnyRedecl*/true);
 
   return nullptr;
 }
@@ -3043,6 +3061,29 @@ void ASTDeclReader::attachPreviousDeclImpl(ASTReader &Reader,
 namespace clang {
 template<>
 void ASTDeclReader::attachPreviousDeclImpl(ASTReader &Reader,
+                                           Redeclarable<VarDecl> *D,
+                                           Decl *Previous, Decl *Canon) {
+  VarDecl *VD = static_cast<VarDecl*>(D);
+  VarDecl *PrevVD = cast<VarDecl>(Previous);
+  D->RedeclLink.setPrevious(PrevVD);
+  D->First = PrevVD->First;
+
+  // We should keep at most one definition on the chain.
+  // FIXME: Cache the definition once we've found it. Building a chain with
+  // N definitions currently takes O(N^2) time here.
+  if (VD->isThisDeclarationADefinition() == VarDecl::Definition) {
+    for (VarDecl *CurD = PrevVD; CurD; CurD = CurD->getPreviousDecl()) {
+      if (CurD->isThisDeclarationADefinition() == VarDecl::Definition) {
+        Reader.mergeDefinitionVisibility(CurD, VD);
+        VD->demoteThisDefinitionToDeclaration();
+        break;
+      }
+    }
+  }
+}
+
+template<>
+void ASTDeclReader::attachPreviousDeclImpl(ASTReader &Reader,
                                            Redeclarable<FunctionDecl> *D,
                                            Decl *Previous, Decl *Canon) {
   FunctionDecl *FD = static_cast<FunctionDecl*>(D);
@@ -3215,13 +3256,12 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
   Deserializing ADecl(this);
 
   DeclsCursor.JumpToBit(Loc.Offset);
-  RecordData Record;
+  ASTRecordReader Record(*this, *Loc.F);
+  ASTDeclReader Reader(*this, Record, Loc, ID, DeclLoc);
   unsigned Code = DeclsCursor.ReadCode();
-  unsigned Idx = 0;
-  ASTDeclReader Reader(*this, Loc, ID, DeclLoc, Record,Idx);
 
   Decl *D = nullptr;
-  switch ((DeclCode)DeclsCursor.readRecord(Code, Record)) {
+  switch ((DeclCode)Record.readRecord(DeclsCursor, Code)) {
   case DECL_CONTEXT_LEXICAL:
   case DECL_CONTEXT_VISIBLE:
     llvm_unreachable("Record cannot be de-serialized with ReadDeclRecord");
@@ -3246,6 +3286,9 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
   case DECL_LINKAGE_SPEC:
     D = LinkageSpecDecl::CreateDeserialized(Context, ID);
     break;
+  case DECL_EXPORT:
+    D = ExportDecl::CreateDeserialized(Context, ID);
+    break;
   case DECL_LABEL:
     D = LabelDecl::CreateDeserialized(Context, ID);
     break;
@@ -3258,6 +3301,9 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
   case DECL_USING:
     D = UsingDecl::CreateDeserialized(Context, ID);
     break;
+  case DECL_USING_PACK:
+    D = UsingPackDecl::CreateDeserialized(Context, ID, Record.readInt());
+    break;
   case DECL_USING_SHADOW:
     D = UsingShadowDecl::CreateDeserialized(Context, ID);
     break;
@@ -3295,7 +3341,7 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
     D = AccessSpecDecl::CreateDeserialized(Context, ID);
     break;
   case DECL_FRIEND:
-    D = FriendDecl::CreateDeserialized(Context, ID, Record[Idx++]);
+    D = FriendDecl::CreateDeserialized(Context, ID, Record.readInt());
     break;
   case DECL_FRIEND_TEMPLATE:
     D = FriendTemplateDecl::CreateDeserialized(Context, ID);
@@ -3331,14 +3377,15 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
     D = NonTypeTemplateParmDecl::CreateDeserialized(Context, ID);
     break;
   case DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK:
-    D = NonTypeTemplateParmDecl::CreateDeserialized(Context, ID, Record[Idx++]);
+    D = NonTypeTemplateParmDecl::CreateDeserialized(Context, ID,
+                                                    Record.readInt());
     break;
   case DECL_TEMPLATE_TEMPLATE_PARM:
     D = TemplateTemplateParmDecl::CreateDeserialized(Context, ID);
     break;
   case DECL_EXPANDED_TEMPLATE_TEMPLATE_PARM_PACK:
     D = TemplateTemplateParmDecl::CreateDeserialized(Context, ID,
-                                                     Record[Idx++]);
+                                                     Record.readInt());
     break;
   case DECL_TYPE_ALIAS_TEMPLATE:
     D = TypeAliasTemplateDecl::CreateDeserialized(Context, ID);
@@ -3394,6 +3441,12 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
   case DECL_PARM_VAR:
     D = ParmVarDecl::CreateDeserialized(Context, ID);
     break;
+  case DECL_DECOMPOSITION:
+    D = DecompositionDecl::CreateDeserialized(Context, ID, Record.readInt());
+    break;
+  case DECL_BINDING:
+    D = BindingDecl::CreateDeserialized(Context, ID);
+    break;
   case DECL_FILE_SCOPE_ASM:
     D = FileScopeAsmDecl::CreateDeserialized(Context, ID);
     break;
@@ -3404,7 +3457,7 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
     D = MSPropertyDecl::CreateDeserialized(Context, ID);
     break;
   case DECL_CAPTURED:
-    D = CapturedDecl::CreateDeserialized(Context, ID, Record[Idx++]);
+    D = CapturedDecl::CreateDeserialized(Context, ID, Record.readInt());
     break;
   case DECL_CXX_BASE_SPECIFIERS:
     Error("attempt to read a C++ base-specifier record as a declaration");
@@ -3418,7 +3471,7 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
     D = ImportDecl::CreateDeserialized(Context, ID, Record.back());
     break;
   case DECL_OMP_THREADPRIVATE:
-    D = OMPThreadPrivateDecl::CreateDeserialized(Context, ID, Record[Idx++]);
+    D = OMPThreadPrivateDecl::CreateDeserialized(Context, ID, Record.readInt());
     break;
   case DECL_OMP_DECLARE_REDUCTION:
     D = OMPDeclareReductionDecl::CreateDeserialized(Context, ID);
@@ -3427,11 +3480,11 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
     D = OMPCapturedExprDecl::CreateDeserialized(Context, ID);
     break;
   case DECL_PRAGMA_COMMENT:
-    D = PragmaCommentDecl::CreateDeserialized(Context, ID, Record[Idx++]);
+    D = PragmaCommentDecl::CreateDeserialized(Context, ID, Record.readInt());
     break;
   case DECL_PRAGMA_DETECT_MISMATCH:
     D = PragmaDetectMismatchDecl::CreateDeserialized(Context, ID,
-                                                     Record[Idx++]);
+                                                     Record.readInt());
     break;
   case DECL_EMPTY:
     D = EmptyDecl::CreateDeserialized(Context, ID);
@@ -3460,21 +3513,24 @@ Decl *ASTReader::ReadDeclRecord(DeclID ID) {
         ReadVisibleDeclContextStorage(*Loc.F, DeclsCursor, Offsets.second, ID))
       return nullptr;
   }
-  assert(Idx == Record.size());
+  assert(Record.getIdx() == Record.size());
 
   // Load any relevant update records.
   PendingUpdateRecords.push_back(std::make_pair(ID, D));
 
   // Load the categories after recursive loading is finished.
   if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(D))
-    if (Class->isThisDeclarationADefinition())
+    // If we already have a definition when deserializing the ObjCInterfaceDecl,
+    // we put the Decl in PendingDefinitions so we can pull the categories here.
+    if (Class->isThisDeclarationADefinition() ||
+        PendingDefinitions.count(Class))
       loadObjCCategories(ID, Class);
   
   // If we have deserialized a declaration that has a definition the
   // AST consumer might need to know about, queue it.
   // We don't pass it to the consumer immediately because we may be in recursive
   // loading, and some declarations may still be initializing.
-  if (isConsumerInterestedIn(D, Reader.hasPendingBody()))
+  if (isConsumerInterestedIn(Context, D, Reader.hasPendingBody()))
     InterestingDecls.push_back(D);
 
   return D;
@@ -3490,28 +3546,27 @@ void ASTReader::loadDeclUpdateRecords(serialization::DeclID ID, Decl *D) {
     auto UpdateOffsets = std::move(UpdI->second);
     DeclUpdateOffsets.erase(UpdI);
 
-    bool WasInteresting = isConsumerInterestedIn(D, false);
+    bool WasInteresting = isConsumerInterestedIn(Context, D, false);
     for (auto &FileAndOffset : UpdateOffsets) {
       ModuleFile *F = FileAndOffset.first;
       uint64_t Offset = FileAndOffset.second;
       llvm::BitstreamCursor &Cursor = F->DeclsCursor;
       SavedStreamPosition SavedPosition(Cursor);
       Cursor.JumpToBit(Offset);
-      RecordData Record;
       unsigned Code = Cursor.ReadCode();
-      unsigned RecCode = Cursor.readRecord(Code, Record);
+      ASTRecordReader Record(*this, *F);
+      unsigned RecCode = Record.readRecord(Cursor, Code);
       (void)RecCode;
       assert(RecCode == DECL_UPDATES && "Expected DECL_UPDATES record!");
 
-      unsigned Idx = 0;
-      ASTDeclReader Reader(*this, RecordLocation(F, Offset), ID,
-                           SourceLocation(), Record, Idx);
-      Reader.UpdateDecl(D, *F, Record);
+      ASTDeclReader Reader(*this, Record, RecordLocation(F, Offset), ID,
+                           SourceLocation());
+      Reader.UpdateDecl(D);
 
       // We might have made this declaration interesting. If so, remember that
       // we need to hand it off to the consumer.
       if (!WasInteresting &&
-          isConsumerInterestedIn(D, Reader.hasPendingBody())) {
+          isConsumerInterestedIn(Context, D, Reader.hasPendingBody())) {
         InterestingDecls.push_back(D);
         WasInteresting = true;
       }
@@ -3578,12 +3633,12 @@ namespace {
   /// interface all the categories for it.
   class ObjCCategoriesVisitor {
     ASTReader &Reader;
-    serialization::GlobalDeclID InterfaceID;
     ObjCInterfaceDecl *Interface;
     llvm::SmallPtrSetImpl<ObjCCategoryDecl *> &Deserialized;
-    unsigned PreviousGeneration;
     ObjCCategoryDecl *Tail;
     llvm::DenseMap<DeclarationName, ObjCCategoryDecl *> NameCategoryMap;
+    serialization::GlobalDeclID InterfaceID;
+    unsigned PreviousGeneration;
     
     void add(ObjCCategoryDecl *Cat) {
       // Only process each category once.
@@ -3626,13 +3681,13 @@ namespace {
     
   public:
     ObjCCategoriesVisitor(ASTReader &Reader,
-                          serialization::GlobalDeclID InterfaceID,
                           ObjCInterfaceDecl *Interface,
-                        llvm::SmallPtrSetImpl<ObjCCategoryDecl *> &Deserialized,
+                          llvm::SmallPtrSetImpl<ObjCCategoryDecl *> &Deserialized,
+                          serialization::GlobalDeclID InterfaceID,
                           unsigned PreviousGeneration)
-      : Reader(Reader), InterfaceID(InterfaceID), Interface(Interface),
-        Deserialized(Deserialized), PreviousGeneration(PreviousGeneration),
-        Tail(nullptr)
+      : Reader(Reader), Interface(Interface), Deserialized(Deserialized),
+        Tail(nullptr), InterfaceID(InterfaceID),
+        PreviousGeneration(PreviousGeneration)
     {
       // Populate the name -> category map with the set of known categories.
       for (auto *Cat : Interface->known_categories()) {
@@ -3687,7 +3742,7 @@ namespace {
 void ASTReader::loadObjCCategories(serialization::GlobalDeclID ID,
                                    ObjCInterfaceDecl *D,
                                    unsigned PreviousGeneration) {
-  ObjCCategoriesVisitor Visitor(*this, ID, D, CategoriesDeserialized,
+  ObjCCategoriesVisitor Visitor(*this, D, CategoriesDeserialized, ID,
                                 PreviousGeneration);
   ModuleMgr.visit(Visitor);
 }
@@ -3713,15 +3768,14 @@ static void forAllLaterRedecls(DeclT *D, Fn F) {
   }
 }
 
-void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
-                               const RecordData &Record) {
-  while (Idx < Record.size()) {
-    switch ((DeclUpdateKind)Record[Idx++]) {
+void ASTDeclReader::UpdateDecl(Decl *D) {
+  while (Record.getIdx() < Record.size()) {
+    switch ((DeclUpdateKind)Record.readInt()) {
     case UPD_CXX_ADDED_IMPLICIT_MEMBER: {
       auto *RD = cast<CXXRecordDecl>(D);
       // FIXME: If we also have an update record for instantiating the
       // definition of D, we need that to happen before we get here.
-      Decl *MD = Reader.ReadDecl(ModuleFile, Record, Idx);
+      Decl *MD = Record.readDecl();
       assert(MD && "couldn't read decl from update record");
       // FIXME: We should call addHiddenDecl instead, to add the member
       // to its DeclContext.
@@ -3731,18 +3785,16 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
 
     case UPD_CXX_ADDED_TEMPLATE_SPECIALIZATION:
       // It will be added to the template's specializations set when loaded.
-      (void)Reader.ReadDecl(ModuleFile, Record, Idx);
+      (void)Record.readDecl();
       break;
 
     case UPD_CXX_ADDED_ANONYMOUS_NAMESPACE: {
-      NamespaceDecl *Anon
-        = Reader.ReadDeclAs<NamespaceDecl>(ModuleFile, Record, Idx);
-      
+      NamespaceDecl *Anon = ReadDeclAs<NamespaceDecl>();
+
       // Each module has its own anonymous namespace, which is disjoint from
       // any other module's anonymous namespaces, so don't attach the anonymous
       // namespace at all.
-      if (ModuleFile.Kind != MK_ImplicitModule &&
-          ModuleFile.Kind != MK_ExplicitModule) {
+      if (!Record.isModule()) {
         if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(D))
           TU->setAnonymousNamespace(Anon);
         else
@@ -3753,7 +3805,7 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
 
     case UPD_CXX_INSTANTIATED_STATIC_DATA_MEMBER:
       cast<VarDecl>(D)->getMemberSpecializationInfo()->setPointOfInstantiation(
-          Reader.ReadSourceLocation(ModuleFile, Record, Idx));
+          ReadSourceLocation());
       break;
 
     case UPD_CXX_INSTANTIATED_DEFAULT_ARGUMENT: {
@@ -3762,7 +3814,7 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
       // We have to read the default argument regardless of whether we use it
       // so that hypothetical further update records aren't messed up.
       // TODO: Add a function to skip over the next expr record.
-      auto DefaultArg = Reader.ReadExpr(F);
+      auto DefaultArg = Record.readExpr();
 
       // Only apply the update if the parameter still has an uninstantiated
       // default argument.
@@ -3771,6 +3823,23 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
       break;
     }
 
+    case UPD_CXX_INSTANTIATED_DEFAULT_MEMBER_INITIALIZER: {
+      auto FD = cast<FieldDecl>(D);
+      auto DefaultInit = Record.readExpr();
+
+      // Only apply the update if the field still has an uninstantiated
+      // default member initializer.
+      if (FD->hasInClassInitializer() && !FD->getInClassInitializer()) {
+        if (DefaultInit)
+          FD->setInClassInitializer(DefaultInit);
+        else
+          // Instantiation failed. We can get here if we serialized an AST for
+          // an invalid program.
+          FD->removeInClassInitializer();
+      }
+      break;
+    }
+
     case UPD_CXX_ADDED_FUNCTION_DEFINITION: {
       FunctionDecl *FD = cast<FunctionDecl>(D);
       if (Reader.PendingBodies[FD]) {
@@ -3779,7 +3848,7 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
         return;
       }
 
-      if (Record[Idx++]) {
+      if (Record.readInt()) {
         // Maintain AST consistency: any later redeclarations of this function
         // are inline if this one is. (We might have merged another declaration
         // into this one.)
@@ -3787,16 +3856,16 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
           FD->setImplicitlyInline();
         });
       }
-      FD->setInnerLocStart(Reader.ReadSourceLocation(ModuleFile, Record, Idx));
+      FD->setInnerLocStart(ReadSourceLocation());
       if (auto *CD = dyn_cast<CXXConstructorDecl>(FD)) {
-        CD->NumCtorInitializers = Record[Idx++];
+        CD->NumCtorInitializers = Record.readInt();
         if (CD->NumCtorInitializers)
-          CD->CtorInitializers = ReadGlobalOffset(F, Record, Idx);
+          CD->CtorInitializers = ReadGlobalOffset();
       }
       // Store the offset of the body so we can lazily load it later.
       Reader.PendingBodies[FD] = GetCurrentCursorOffset();
       HasPendingBody = true;
-      assert(Idx == Record.size() && "lazy body must be last");
+      assert(Record.getIdx() == Record.size() && "lazy body must be last");
       break;
     }
 
@@ -3809,15 +3878,14 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
       ReadCXXRecordDefinition(RD, /*Update*/true);
 
       // Visible update is handled separately.
-      uint64_t LexicalOffset = ReadLocalOffset(Record, Idx);
+      uint64_t LexicalOffset = ReadLocalOffset();
       if (!HadRealDefinition && LexicalOffset) {
-        Reader.ReadLexicalDeclContextStorage(ModuleFile, ModuleFile.DeclsCursor,
-                                             LexicalOffset, RD);
+        Record.readLexicalDeclContextStorage(LexicalOffset, RD);
         Reader.PendingFakeDefinitionData.erase(OldDD);
       }
 
-      auto TSK = (TemplateSpecializationKind)Record[Idx++];
-      SourceLocation POI = Reader.ReadSourceLocation(ModuleFile, Record, Idx);
+      auto TSK = (TemplateSpecializationKind)Record.readInt();
+      SourceLocation POI = ReadSourceLocation();
       if (MemberSpecializationInfo *MSInfo =
               RD->getMemberSpecializationInfo()) {
         MSInfo->setTemplateSpecializationKind(TSK);
@@ -3828,11 +3896,11 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
         Spec->setTemplateSpecializationKind(TSK);
         Spec->setPointOfInstantiation(POI);
 
-        if (Record[Idx++]) {
+        if (Record.readInt()) {
           auto PartialSpec =
-              ReadDeclAs<ClassTemplatePartialSpecializationDecl>(Record, Idx);
+              ReadDeclAs<ClassTemplatePartialSpecializationDecl>();
           SmallVector<TemplateArgument, 8> TemplArgs;
-          Reader.ReadTemplateArgumentList(TemplArgs, F, Record, Idx);
+          Record.readTemplateArgumentList(TemplArgs);
           auto *TemplArgList = TemplateArgumentList::CreateCopy(
               Reader.getContext(), TemplArgs);
 
@@ -3844,15 +3912,18 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
         }
       }
 
-      RD->setTagKind((TagTypeKind)Record[Idx++]);
-      RD->setLocation(Reader.ReadSourceLocation(ModuleFile, Record, Idx));
-      RD->setLocStart(Reader.ReadSourceLocation(ModuleFile, Record, Idx));
-      RD->setBraceRange(Reader.ReadSourceRange(ModuleFile, Record, Idx));
+      RD->setTagKind((TagTypeKind)Record.readInt());
+      RD->setLocation(ReadSourceLocation());
+      RD->setLocStart(ReadSourceLocation());
+      RD->setBraceRange(ReadSourceRange());
 
-      if (Record[Idx++]) {
+      if (Record.readInt()) {
         AttrVec Attrs;
-        Reader.ReadAttributes(F, Attrs, Record, Idx);
-        D->setAttrsImpl(Attrs, Reader.getContext());
+        Record.readAttributes(Attrs);
+        // If the declaration already has attributes, we assume that some other
+        // AST file already loaded them.
+        if (!D->hasAttrs())
+          D->setAttrsImpl(Attrs, Reader.getContext());
       }
       break;
     }
@@ -3860,7 +3931,7 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
     case UPD_CXX_RESOLVED_DTOR_DELETE: {
       // Set the 'operator delete' directly to avoid emitting another update
       // record.
-      auto *Del = Reader.ReadDeclAs<FunctionDecl>(ModuleFile, Record, Idx);
+      auto *Del = ReadDeclAs<FunctionDecl>();
       auto *First = cast<CXXDestructorDecl>(D->getCanonicalDecl());
       // FIXME: Check consistency if we have an old and new operator delete.
       if (!First->OperatorDelete)
@@ -3871,7 +3942,7 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
     case UPD_CXX_RESOLVED_EXCEPTION_SPEC: {
       FunctionProtoType::ExceptionSpecInfo ESI;
       SmallVector<QualType, 8> ExceptionStorage;
-      Reader.readExceptionSpec(ModuleFile, ExceptionStorage, ESI, Record, Idx);
+      Record.readExceptionSpec(ExceptionStorage, ESI);
 
       // Update this declaration's exception specification, if needed.
       auto *FD = cast<FunctionDecl>(D);
@@ -3893,7 +3964,7 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
 
     case UPD_CXX_DEDUCED_RETURN_TYPE: {
       // FIXME: Also do this when merging redecls.
-      QualType DeducedResultType = Reader.readType(ModuleFile, Record, Idx);
+      QualType DeducedResultType = Record.readType();
       for (auto *Redecl : merged_redecls(D)) {
         // FIXME: If the return type is already deduced, check that it matches.
         FunctionDecl *FD = cast<FunctionDecl>(Redecl);
@@ -3909,20 +3980,20 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
     }
 
     case UPD_MANGLING_NUMBER:
-      Reader.Context.setManglingNumber(cast<NamedDecl>(D), Record[Idx++]);
+      Reader.Context.setManglingNumber(cast<NamedDecl>(D), Record.readInt());
       break;
 
     case UPD_STATIC_LOCAL_NUMBER:
-      Reader.Context.setStaticLocalNumber(cast<VarDecl>(D), Record[Idx++]);
+      Reader.Context.setStaticLocalNumber(cast<VarDecl>(D), Record.readInt());
       break;
 
     case UPD_DECL_MARKED_OPENMP_THREADPRIVATE:
       D->addAttr(OMPThreadPrivateDeclAttr::CreateImplicit(
-          Reader.Context, ReadSourceRange(Record, Idx)));
+          Reader.Context, ReadSourceRange()));
       break;
 
     case UPD_DECL_EXPORTED: {
-      unsigned SubmoduleID = readSubmoduleID(Record, Idx);
+      unsigned SubmoduleID = readSubmoduleID();
       auto *Exported = cast<NamedDecl>(D);
       if (auto *TD = dyn_cast<TagDecl>(Exported))
         Exported = TD->getDefinition();
@@ -3946,7 +4017,7 @@ void ASTDeclReader::UpdateDecl(Decl *D, ModuleFile &ModuleFile,
     case UPD_DECL_MARKED_OPENMP_DECLARETARGET:
     case UPD_ADDED_ATTR_TO_RECORD:
       AttrVec Attrs;
-      Reader.ReadAttributes(F, Attrs, Record, Idx);
+      Record.readAttributes(Attrs);
       assert(Attrs.size() == 1);
       D->addAttr(Attrs[0]);
       break;
diff --git a/lib/Serialization/ASTReaderInternals.h b/lib/Serialization/ASTReaderInternals.h
index d392364a971b..6cb4d662e338 100644
--- a/lib/Serialization/ASTReaderInternals.h
+++ b/lib/Serialization/ASTReaderInternals.h
@@ -13,14 +13,12 @@
 #ifndef LLVM_CLANG_LIB_SERIALIZATION_ASTREADERINTERNALS_H
 #define LLVM_CLANG_LIB_SERIALIZATION_ASTREADERINTERNALS_H
 
+#include "MultiOnDiskHashTable.h"
 #include "clang/AST/DeclarationName.h"
 #include "clang/Serialization/ASTBitCodes.h"
 #include "llvm/ADT/DenseSet.h"
-#include "llvm/ADT/PointerUnion.h"
-#include "llvm/ADT/TinyPtrVector.h"
 #include "llvm/Support/Endian.h"
 #include "llvm/Support/OnDiskHashTable.h"
-#include "MultiOnDiskHashTable.h"
 #include <utility>
 
 namespace clang {
@@ -112,17 +110,6 @@ public:
 
 struct DeclContextLookupTable {
   MultiOnDiskHashTable<ASTDeclContextNameLookupTrait> Table;
-
-  // These look redundant, but don't remove them -- they work around MSVC 2013's
-  // inability to synthesize move operations. Without them, the
-  // MultiOnDiskHashTable will be copied (despite being move-only!).
-  DeclContextLookupTable() : Table() {}
-  DeclContextLookupTable(DeclContextLookupTable &&O)
-      : Table(std::move(O.Table)) {}
-  DeclContextLookupTable &operator=(DeclContextLookupTable &&O) {
-    Table = std::move(O.Table);
-    return *this;
-  }
 };
 
 /// \brief Base class for the trait describing the on-disk hash table for the
@@ -259,7 +246,7 @@ public:
   struct internal_key_type {
     off_t Size;
     time_t ModTime;
-    const char *Filename;
+    StringRef Filename;
     bool Imported;
   };
   typedef const internal_key_type &internal_key_ref;
diff --git a/lib/Serialization/ASTReaderStmt.cpp b/lib/Serialization/ASTReaderStmt.cpp
index 395da42d4f24..5607f764a9c3 100644
--- a/lib/Serialization/ASTReaderStmt.cpp
+++ b/lib/Serialization/ASTReaderStmt.cpp
@@ -26,62 +26,47 @@ namespace clang {
 
   class ASTStmtReader : public StmtVisitor<ASTStmtReader> {
     friend class OMPClauseReader;
-    typedef ASTReader::RecordData RecordData;
-    
-    ASTReader &Reader;
-    ModuleFile &F;
+
+    ASTRecordReader &Record;
     llvm::BitstreamCursor &DeclsCursor;
-    const ASTReader::RecordData &Record;
-    unsigned &Idx;
 
-    Token ReadToken(const RecordData &R, unsigned &I) {
-      return Reader.ReadToken(F, R, I);
+    SourceLocation ReadSourceLocation() {
+      return Record.readSourceLocation();
     }
 
-    SourceLocation ReadSourceLocation(const RecordData &R, unsigned &I) {
-      return Reader.ReadSourceLocation(F, R, I);
+    SourceRange ReadSourceRange() {
+      return Record.readSourceRange();
     }
 
-    SourceRange ReadSourceRange(const RecordData &R, unsigned &I) {
-      return Reader.ReadSourceRange(F, R, I);
+    std::string ReadString() {
+      return Record.readString();
     }
 
-    std::string ReadString(const RecordData &R, unsigned &I) {
-      return Reader.ReadString(R, I);
-    }
-        
-    TypeSourceInfo *GetTypeSourceInfo(const RecordData &R, unsigned &I) {
-      return Reader.GetTypeSourceInfo(F, R, I);
-    }
-    
-    serialization::DeclID ReadDeclID(const RecordData &R, unsigned &I) {
-      return Reader.ReadDeclID(F, R, I);
+    TypeSourceInfo *GetTypeSourceInfo() {
+      return Record.getTypeSourceInfo();
     }
-    
-    Decl *ReadDecl(const RecordData &R, unsigned &I) {
-      return Reader.ReadDecl(F, R, I);
+
+    Decl *ReadDecl() {
+      return Record.readDecl();
     }
-    
+
     template<typename T>
-    T *ReadDeclAs(const RecordData &R, unsigned &I) {
-      return Reader.ReadDeclAs<T>(F, R, I);
+    T *ReadDeclAs() {
+      return Record.readDeclAs<T>();
     }
 
-    void ReadDeclarationNameLoc(DeclarationNameLoc &DNLoc, DeclarationName Name,
-                                const ASTReader::RecordData &R, unsigned &I) {
-      Reader.ReadDeclarationNameLoc(F, DNLoc, Name, R, I);
+    void ReadDeclarationNameLoc(DeclarationNameLoc &DNLoc,
+                                DeclarationName Name) {
+      Record.readDeclarationNameLoc(DNLoc, Name);
     }
-    
-    void ReadDeclarationNameInfo(DeclarationNameInfo &NameInfo,
-                                const ASTReader::RecordData &R, unsigned &I) {
-      Reader.ReadDeclarationNameInfo(F, NameInfo, R, I);
+
+    void ReadDeclarationNameInfo(DeclarationNameInfo &NameInfo) {
+      Record.readDeclarationNameInfo(NameInfo);
     }
 
   public:
-    ASTStmtReader(ASTReader &Reader, ModuleFile &F,
-                  llvm::BitstreamCursor &Cursor,
-                  const ASTReader::RecordData &Record, unsigned &Idx)
-      : Reader(Reader), F(F), DeclsCursor(Cursor), Record(Record), Idx(Idx) { }
+    ASTStmtReader(ASTRecordReader &Record, llvm::BitstreamCursor &Cursor)
+        : Record(Record), DeclsCursor(Cursor) {}
 
     /// \brief The number of record fields required for the Stmt class
     /// itself.
@@ -109,106 +94,103 @@ namespace clang {
 void ASTStmtReader::ReadTemplateKWAndArgsInfo(ASTTemplateKWAndArgsInfo &Args,
                                               TemplateArgumentLoc *ArgsLocArray,
                                               unsigned NumTemplateArgs) {
-  SourceLocation TemplateKWLoc = ReadSourceLocation(Record, Idx);
+  SourceLocation TemplateKWLoc = ReadSourceLocation();
   TemplateArgumentListInfo ArgInfo;
-  ArgInfo.setLAngleLoc(ReadSourceLocation(Record, Idx));
-  ArgInfo.setRAngleLoc(ReadSourceLocation(Record, Idx));
+  ArgInfo.setLAngleLoc(ReadSourceLocation());
+  ArgInfo.setRAngleLoc(ReadSourceLocation());
   for (unsigned i = 0; i != NumTemplateArgs; ++i)
-    ArgInfo.addArgument(
-        Reader.ReadTemplateArgumentLoc(F, Record, Idx));
+    ArgInfo.addArgument(Record.readTemplateArgumentLoc());
   Args.initializeFrom(TemplateKWLoc, ArgInfo, ArgsLocArray);
 }
 
 void ASTStmtReader::VisitStmt(Stmt *S) {
-  assert(Idx == NumStmtFields && "Incorrect statement field count");
+  assert(Record.getIdx() == NumStmtFields && "Incorrect statement field count");
 }
 
 void ASTStmtReader::VisitNullStmt(NullStmt *S) {
   VisitStmt(S);
-  S->setSemiLoc(ReadSourceLocation(Record, Idx));
-  S->HasLeadingEmptyMacro = Record[Idx++];
+  S->setSemiLoc(ReadSourceLocation());
+  S->HasLeadingEmptyMacro = Record.readInt();
 }
 
 void ASTStmtReader::VisitCompoundStmt(CompoundStmt *S) {
   VisitStmt(S);
   SmallVector<Stmt *, 16> Stmts;
-  unsigned NumStmts = Record[Idx++];
+  unsigned NumStmts = Record.readInt();
   while (NumStmts--)
-    Stmts.push_back(Reader.ReadSubStmt());
-  S->setStmts(Reader.getContext(), Stmts);
-  S->LBraceLoc = ReadSourceLocation(Record, Idx);
-  S->RBraceLoc = ReadSourceLocation(Record, Idx);
+    Stmts.push_back(Record.readSubStmt());
+  S->setStmts(Record.getContext(), Stmts);
+  S->LBraceLoc = ReadSourceLocation();
+  S->RBraceLoc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitSwitchCase(SwitchCase *S) {
   VisitStmt(S);
-  Reader.RecordSwitchCaseID(S, Record[Idx++]);
-  S->setKeywordLoc(ReadSourceLocation(Record, Idx));
-  S->setColonLoc(ReadSourceLocation(Record, Idx));
+  Record.recordSwitchCaseID(S, Record.readInt());
+  S->setKeywordLoc(ReadSourceLocation());
+  S->setColonLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitCaseStmt(CaseStmt *S) {
   VisitSwitchCase(S);
-  S->setLHS(Reader.ReadSubExpr());
-  S->setRHS(Reader.ReadSubExpr());
-  S->setSubStmt(Reader.ReadSubStmt());
-  S->setEllipsisLoc(ReadSourceLocation(Record, Idx));
+  S->setLHS(Record.readSubExpr());
+  S->setRHS(Record.readSubExpr());
+  S->setSubStmt(Record.readSubStmt());
+  S->setEllipsisLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitDefaultStmt(DefaultStmt *S) {
   VisitSwitchCase(S);
-  S->setSubStmt(Reader.ReadSubStmt());
+  S->setSubStmt(Record.readSubStmt());
 }
 
 void ASTStmtReader::VisitLabelStmt(LabelStmt *S) {
   VisitStmt(S);
-  LabelDecl *LD = ReadDeclAs<LabelDecl>(Record, Idx);
+  LabelDecl *LD = ReadDeclAs<LabelDecl>();
   LD->setStmt(S);
   S->setDecl(LD);
-  S->setSubStmt(Reader.ReadSubStmt());
-  S->setIdentLoc(ReadSourceLocation(Record, Idx));
+  S->setSubStmt(Record.readSubStmt());
+  S->setIdentLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitAttributedStmt(AttributedStmt *S) {
   VisitStmt(S);
-  uint64_t NumAttrs = Record[Idx++];
+  uint64_t NumAttrs = Record.readInt();
   AttrVec Attrs;
-  Reader.ReadAttributes(F, Attrs, Record, Idx);
+  Record.readAttributes(Attrs);
   (void)NumAttrs;
   assert(NumAttrs == S->NumAttrs);
   assert(NumAttrs == Attrs.size());
   std::copy(Attrs.begin(), Attrs.end(), S->getAttrArrayPtr());
-  S->SubStmt = Reader.ReadSubStmt();
-  S->AttrLoc = ReadSourceLocation(Record, Idx);
+  S->SubStmt = Record.readSubStmt();
+  S->AttrLoc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitIfStmt(IfStmt *S) {
   VisitStmt(S);
-  S->setConstexpr(Record[Idx++]);
-  S->setInit(Reader.ReadSubStmt());
-  S->setConditionVariable(Reader.getContext(),
-                          ReadDeclAs<VarDecl>(Record, Idx));
-  S->setCond(Reader.ReadSubExpr());
-  S->setThen(Reader.ReadSubStmt());
-  S->setElse(Reader.ReadSubStmt());
-  S->setIfLoc(ReadSourceLocation(Record, Idx));
-  S->setElseLoc(ReadSourceLocation(Record, Idx));
+  S->setConstexpr(Record.readInt());
+  S->setInit(Record.readSubStmt());
+  S->setConditionVariable(Record.getContext(), ReadDeclAs<VarDecl>());
+  S->setCond(Record.readSubExpr());
+  S->setThen(Record.readSubStmt());
+  S->setElse(Record.readSubStmt());
+  S->setIfLoc(ReadSourceLocation());
+  S->setElseLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitSwitchStmt(SwitchStmt *S) {
   VisitStmt(S);
-  S->setInit(Reader.ReadSubStmt());
-  S->setConditionVariable(Reader.getContext(),
-                          ReadDeclAs<VarDecl>(Record, Idx));
-  S->setCond(Reader.ReadSubExpr());
-  S->setBody(Reader.ReadSubStmt());
-  S->setSwitchLoc(ReadSourceLocation(Record, Idx));
-  if (Record[Idx++])
+  S->setInit(Record.readSubStmt());
+  S->setConditionVariable(Record.getContext(), ReadDeclAs<VarDecl>());
+  S->setCond(Record.readSubExpr());
+  S->setBody(Record.readSubStmt());
+  S->setSwitchLoc(ReadSourceLocation());
+  if (Record.readInt())
     S->setAllEnumCasesCovered();
 
   SwitchCase *PrevSC = nullptr;
-  for (unsigned N = Record.size(); Idx != N; ++Idx) {
-    SwitchCase *SC = Reader.getSwitchCaseWithID(Record[Idx]);
+  for (auto E = Record.size(); Record.getIdx() != E; ) {
+    SwitchCase *SC = Record.getSwitchCaseWithID(Record.readInt());
     if (PrevSC)
       PrevSC->setNextSwitchCase(SC);
     else
@@ -220,81 +202,80 @@ void ASTStmtReader::VisitSwitchStmt(SwitchStmt *S) {
 
 void ASTStmtReader::VisitWhileStmt(WhileStmt *S) {
   VisitStmt(S);
-  S->setConditionVariable(Reader.getContext(),
-                          ReadDeclAs<VarDecl>(Record, Idx));
+  S->setConditionVariable(Record.getContext(), ReadDeclAs<VarDecl>());
 
-  S->setCond(Reader.ReadSubExpr());
-  S->setBody(Reader.ReadSubStmt());
-  S->setWhileLoc(ReadSourceLocation(Record, Idx));
+  S->setCond(Record.readSubExpr());
+  S->setBody(Record.readSubStmt());
+  S->setWhileLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitDoStmt(DoStmt *S) {
   VisitStmt(S);
-  S->setCond(Reader.ReadSubExpr());
-  S->setBody(Reader.ReadSubStmt());
-  S->setDoLoc(ReadSourceLocation(Record, Idx));
-  S->setWhileLoc(ReadSourceLocation(Record, Idx));
-  S->setRParenLoc(ReadSourceLocation(Record, Idx));
+  S->setCond(Record.readSubExpr());
+  S->setBody(Record.readSubStmt());
+  S->setDoLoc(ReadSourceLocation());
+  S->setWhileLoc(ReadSourceLocation());
+  S->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitForStmt(ForStmt *S) {
   VisitStmt(S);
-  S->setInit(Reader.ReadSubStmt());
-  S->setCond(Reader.ReadSubExpr());
-  S->setConditionVariable(Reader.getContext(),
-                          ReadDeclAs<VarDecl>(Record, Idx));
-  S->setInc(Reader.ReadSubExpr());
-  S->setBody(Reader.ReadSubStmt());
-  S->setForLoc(ReadSourceLocation(Record, Idx));
-  S->setLParenLoc(ReadSourceLocation(Record, Idx));
-  S->setRParenLoc(ReadSourceLocation(Record, Idx));
+  S->setInit(Record.readSubStmt());
+  S->setCond(Record.readSubExpr());
+  S->setConditionVariable(Record.getContext(), ReadDeclAs<VarDecl>());
+  S->setInc(Record.readSubExpr());
+  S->setBody(Record.readSubStmt());
+  S->setForLoc(ReadSourceLocation());
+  S->setLParenLoc(ReadSourceLocation());
+  S->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitGotoStmt(GotoStmt *S) {
   VisitStmt(S);
-  S->setLabel(ReadDeclAs<LabelDecl>(Record, Idx));
-  S->setGotoLoc(ReadSourceLocation(Record, Idx));
-  S->setLabelLoc(ReadSourceLocation(Record, Idx));
+  S->setLabel(ReadDeclAs<LabelDecl>());
+  S->setGotoLoc(ReadSourceLocation());
+  S->setLabelLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitIndirectGotoStmt(IndirectGotoStmt *S) {
   VisitStmt(S);
-  S->setGotoLoc(ReadSourceLocation(Record, Idx));
-  S->setStarLoc(ReadSourceLocation(Record, Idx));
-  S->setTarget(Reader.ReadSubExpr());
+  S->setGotoLoc(ReadSourceLocation());
+  S->setStarLoc(ReadSourceLocation());
+  S->setTarget(Record.readSubExpr());
 }
 
 void ASTStmtReader::VisitContinueStmt(ContinueStmt *S) {
   VisitStmt(S);
-  S->setContinueLoc(ReadSourceLocation(Record, Idx));
+  S->setContinueLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitBreakStmt(BreakStmt *S) {
   VisitStmt(S);
-  S->setBreakLoc(ReadSourceLocation(Record, Idx));
+  S->setBreakLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitReturnStmt(ReturnStmt *S) {
   VisitStmt(S);
-  S->setRetValue(Reader.ReadSubExpr());
-  S->setReturnLoc(ReadSourceLocation(Record, Idx));
-  S->setNRVOCandidate(ReadDeclAs<VarDecl>(Record, Idx));
+  S->setRetValue(Record.readSubExpr());
+  S->setReturnLoc(ReadSourceLocation());
+  S->setNRVOCandidate(ReadDeclAs<VarDecl>());
 }
 
 void ASTStmtReader::VisitDeclStmt(DeclStmt *S) {
   VisitStmt(S);
-  S->setStartLoc(ReadSourceLocation(Record, Idx));
-  S->setEndLoc(ReadSourceLocation(Record, Idx));
+  S->setStartLoc(ReadSourceLocation());
+  S->setEndLoc(ReadSourceLocation());
 
-  if (Idx + 1 == Record.size()) {
+  if (Record.size() - Record.getIdx() == 1) {
     // Single declaration
-    S->setDeclGroup(DeclGroupRef(ReadDecl(Record, Idx)));
+    S->setDeclGroup(DeclGroupRef(ReadDecl()));
   } else {
     SmallVector<Decl *, 16> Decls;
-    Decls.reserve(Record.size() - Idx);    
-    for (unsigned N = Record.size(); Idx != N; )
-      Decls.push_back(ReadDecl(Record, Idx));
-    S->setDeclGroup(DeclGroupRef(DeclGroup::Create(Reader.getContext(),
+    int N = Record.size() - Record.getIdx();
+    Decls.reserve(N);
+    for (int I = 0; I < N; ++I)
+      Decls.push_back(ReadDecl());
+    S->setDeclGroup(DeclGroupRef(DeclGroup::Create(Record.getContext(),
                                                    Decls.data(),
                                                    Decls.size())));
   }
@@ -302,18 +283,18 @@ void ASTStmtReader::VisitDeclStmt(DeclStmt *S) {
 
 void ASTStmtReader::VisitAsmStmt(AsmStmt *S) {
   VisitStmt(S);
-  S->NumOutputs = Record[Idx++];
-  S->NumInputs = Record[Idx++];
-  S->NumClobbers = Record[Idx++];
-  S->setAsmLoc(ReadSourceLocation(Record, Idx));
-  S->setVolatile(Record[Idx++]);
-  S->setSimple(Record[Idx++]);
+  S->NumOutputs = Record.readInt();
+  S->NumInputs = Record.readInt();
+  S->NumClobbers = Record.readInt();
+  S->setAsmLoc(ReadSourceLocation());
+  S->setVolatile(Record.readInt());
+  S->setSimple(Record.readInt());
 }
 
 void ASTStmtReader::VisitGCCAsmStmt(GCCAsmStmt *S) {
   VisitAsmStmt(S);
-  S->setRParenLoc(ReadSourceLocation(Record, Idx));
-  S->setAsmString(cast_or_null<StringLiteral>(Reader.ReadSubStmt()));
+  S->setRParenLoc(ReadSourceLocation());
+  S->setAsmString(cast_or_null<StringLiteral>(Record.readSubStmt()));
 
   unsigned NumOutputs = S->getNumOutputs();
   unsigned NumInputs = S->getNumInputs();
@@ -324,34 +305,34 @@ void ASTStmtReader::VisitGCCAsmStmt(GCCAsmStmt *S) {
   SmallVector<StringLiteral*, 16> Constraints;
   SmallVector<Stmt*, 16> Exprs;
   for (unsigned I = 0, N = NumOutputs + NumInputs; I != N; ++I) {
-    Names.push_back(Reader.GetIdentifierInfo(F, Record, Idx));
-    Constraints.push_back(cast_or_null<StringLiteral>(Reader.ReadSubStmt()));
-    Exprs.push_back(Reader.ReadSubStmt());
+    Names.push_back(Record.getIdentifierInfo());
+    Constraints.push_back(cast_or_null<StringLiteral>(Record.readSubStmt()));
+    Exprs.push_back(Record.readSubStmt());
   }
 
   // Constraints
   SmallVector<StringLiteral*, 16> Clobbers;
   for (unsigned I = 0; I != NumClobbers; ++I)
-    Clobbers.push_back(cast_or_null<StringLiteral>(Reader.ReadSubStmt()));
+    Clobbers.push_back(cast_or_null<StringLiteral>(Record.readSubStmt()));
 
-  S->setOutputsAndInputsAndClobbers(Reader.getContext(),
-                                    Names.data(), Constraints.data(), 
-                                    Exprs.data(), NumOutputs, NumInputs, 
+  S->setOutputsAndInputsAndClobbers(Record.getContext(),
+                                    Names.data(), Constraints.data(),
+                                    Exprs.data(), NumOutputs, NumInputs,
                                     Clobbers.data(), NumClobbers);
 }
 
 void ASTStmtReader::VisitMSAsmStmt(MSAsmStmt *S) {
   VisitAsmStmt(S);
-  S->LBraceLoc = ReadSourceLocation(Record, Idx);
-  S->EndLoc = ReadSourceLocation(Record, Idx);
-  S->NumAsmToks = Record[Idx++];
-  std::string AsmStr = ReadString(Record, Idx);
+  S->LBraceLoc = ReadSourceLocation();
+  S->EndLoc = ReadSourceLocation();
+  S->NumAsmToks = Record.readInt();
+  std::string AsmStr = ReadString();
 
   // Read the tokens.
   SmallVector<Token, 16> AsmToks;
   AsmToks.reserve(S->NumAsmToks);
   for (unsigned i = 0, e = S->NumAsmToks; i != e; ++i) {
-    AsmToks.push_back(ReadToken(Record, Idx));
+    AsmToks.push_back(Record.readToken());
   }
 
   // The calls to reserve() for the FooData vectors are mandatory to
@@ -363,7 +344,7 @@ void ASTStmtReader::VisitMSAsmStmt(MSAsmStmt *S) {
   ClobbersData.reserve(S->NumClobbers);
   Clobbers.reserve(S->NumClobbers);
   for (unsigned i = 0, e = S->NumClobbers; i != e; ++i) {
-    ClobbersData.push_back(ReadString(Record, Idx));
+    ClobbersData.push_back(ReadString());
     Clobbers.push_back(ClobbersData.back());
   }
 
@@ -376,12 +357,12 @@ void ASTStmtReader::VisitMSAsmStmt(MSAsmStmt *S) {
   ConstraintsData.reserve(NumOperands);
   Constraints.reserve(NumOperands);
   for (unsigned i = 0; i != NumOperands; ++i) {
-    Exprs.push_back(cast<Expr>(Reader.ReadSubStmt()));
-    ConstraintsData.push_back(ReadString(Record, Idx));
+    Exprs.push_back(cast<Expr>(Record.readSubStmt()));
+    ConstraintsData.push_back(ReadString());
     Constraints.push_back(ConstraintsData.back());
   }
 
-  S->initialize(Reader.getContext(), AsmStr, AsmToks,
+  S->initialize(Record.getContext(), AsmStr, AsmToks,
                 Constraints, Exprs, Clobbers);
 }
 
@@ -407,229 +388,229 @@ void ASTStmtReader::VisitCoyieldExpr(CoyieldExpr *S) {
 
 void ASTStmtReader::VisitCapturedStmt(CapturedStmt *S) {
   VisitStmt(S);
-  ++Idx;
-  S->setCapturedDecl(ReadDeclAs<CapturedDecl>(Record, Idx));
-  S->setCapturedRegionKind(static_cast<CapturedRegionKind>(Record[Idx++]));
-  S->setCapturedRecordDecl(ReadDeclAs<RecordDecl>(Record, Idx));
+  Record.skipInts(1);
+  S->setCapturedDecl(ReadDeclAs<CapturedDecl>());
+  S->setCapturedRegionKind(static_cast<CapturedRegionKind>(Record.readInt()));
+  S->setCapturedRecordDecl(ReadDeclAs<RecordDecl>());
 
   // Capture inits
   for (CapturedStmt::capture_init_iterator I = S->capture_init_begin(),
                                            E = S->capture_init_end();
        I != E; ++I)
-    *I = Reader.ReadSubExpr();
+    *I = Record.readSubExpr();
 
   // Body
-  S->setCapturedStmt(Reader.ReadSubStmt());
+  S->setCapturedStmt(Record.readSubStmt());
   S->getCapturedDecl()->setBody(S->getCapturedStmt());
 
   // Captures
   for (auto &I : S->captures()) {
-    I.VarAndKind.setPointer(ReadDeclAs<VarDecl>(Record, Idx));
-    I.VarAndKind
-        .setInt(static_cast<CapturedStmt::VariableCaptureKind>(Record[Idx++]));
-    I.Loc = ReadSourceLocation(Record, Idx);
+    I.VarAndKind.setPointer(ReadDeclAs<VarDecl>());
+    I.VarAndKind.setInt(
+        static_cast<CapturedStmt::VariableCaptureKind>(Record.readInt()));
+    I.Loc = ReadSourceLocation();
   }
 }
 
 void ASTStmtReader::VisitExpr(Expr *E) {
   VisitStmt(E);
-  E->setType(Reader.readType(F, Record, Idx));
-  E->setTypeDependent(Record[Idx++]);
-  E->setValueDependent(Record[Idx++]);
-  E->setInstantiationDependent(Record[Idx++]);
-  E->ExprBits.ContainsUnexpandedParameterPack = Record[Idx++];
-  E->setValueKind(static_cast<ExprValueKind>(Record[Idx++]));
-  E->setObjectKind(static_cast<ExprObjectKind>(Record[Idx++]));
-  assert(Idx == NumExprFields && "Incorrect expression field count");
+  E->setType(Record.readType());
+  E->setTypeDependent(Record.readInt());
+  E->setValueDependent(Record.readInt());
+  E->setInstantiationDependent(Record.readInt());
+  E->ExprBits.ContainsUnexpandedParameterPack = Record.readInt();
+  E->setValueKind(static_cast<ExprValueKind>(Record.readInt()));
+  E->setObjectKind(static_cast<ExprObjectKind>(Record.readInt()));
+  assert(Record.getIdx() == NumExprFields &&
+         "Incorrect expression field count");
 }
 
 void ASTStmtReader::VisitPredefinedExpr(PredefinedExpr *E) {
   VisitExpr(E);
-  E->setLocation(ReadSourceLocation(Record, Idx));
-  E->Type = (PredefinedExpr::IdentType)Record[Idx++];
-  E->FnName = cast_or_null<StringLiteral>(Reader.ReadSubExpr());
+  E->setLocation(ReadSourceLocation());
+  E->Type = (PredefinedExpr::IdentType)Record.readInt();
+  E->FnName = cast_or_null<StringLiteral>(Record.readSubExpr());
 }
 
 void ASTStmtReader::VisitDeclRefExpr(DeclRefExpr *E) {
   VisitExpr(E);
 
-  E->DeclRefExprBits.HasQualifier = Record[Idx++];
-  E->DeclRefExprBits.HasFoundDecl = Record[Idx++];
-  E->DeclRefExprBits.HasTemplateKWAndArgsInfo = Record[Idx++];
-  E->DeclRefExprBits.HadMultipleCandidates = Record[Idx++];
-  E->DeclRefExprBits.RefersToEnclosingVariableOrCapture = Record[Idx++];
+  E->DeclRefExprBits.HasQualifier = Record.readInt();
+  E->DeclRefExprBits.HasFoundDecl = Record.readInt();
+  E->DeclRefExprBits.HasTemplateKWAndArgsInfo = Record.readInt();
+  E->DeclRefExprBits.HadMultipleCandidates = Record.readInt();
+  E->DeclRefExprBits.RefersToEnclosingVariableOrCapture = Record.readInt();
   unsigned NumTemplateArgs = 0;
   if (E->hasTemplateKWAndArgsInfo())
-    NumTemplateArgs = Record[Idx++];
+    NumTemplateArgs = Record.readInt();
 
   if (E->hasQualifier())
     new (E->getTrailingObjects<NestedNameSpecifierLoc>())
-        NestedNameSpecifierLoc(
-            Reader.ReadNestedNameSpecifierLoc(F, Record, Idx));
+        NestedNameSpecifierLoc(Record.readNestedNameSpecifierLoc());
 
   if (E->hasFoundDecl())
-    *E->getTrailingObjects<NamedDecl *>() = ReadDeclAs<NamedDecl>(Record, Idx);
+    *E->getTrailingObjects<NamedDecl *>() = ReadDeclAs<NamedDecl>();
 
   if (E->hasTemplateKWAndArgsInfo())
     ReadTemplateKWAndArgsInfo(
         *E->getTrailingObjects<ASTTemplateKWAndArgsInfo>(),
         E->getTrailingObjects<TemplateArgumentLoc>(), NumTemplateArgs);
 
-  E->setDecl(ReadDeclAs<ValueDecl>(Record, Idx));
-  E->setLocation(ReadSourceLocation(Record, Idx));
-  ReadDeclarationNameLoc(E->DNLoc, E->getDecl()->getDeclName(), Record, Idx);
+  E->setDecl(ReadDeclAs<ValueDecl>());
+  E->setLocation(ReadSourceLocation());
+  ReadDeclarationNameLoc(E->DNLoc, E->getDecl()->getDeclName());
 }
 
 void ASTStmtReader::VisitIntegerLiteral(IntegerLiteral *E) {
   VisitExpr(E);
-  E->setLocation(ReadSourceLocation(Record, Idx));
-  E->setValue(Reader.getContext(), Reader.ReadAPInt(Record, Idx));
+  E->setLocation(ReadSourceLocation());
+  E->setValue(Record.getContext(), Record.readAPInt());
 }
 
 void ASTStmtReader::VisitFloatingLiteral(FloatingLiteral *E) {
   VisitExpr(E);
-  E->setRawSemantics(static_cast<Stmt::APFloatSemantics>(Record[Idx++]));
-  E->setExact(Record[Idx++]);
-  E->setValue(Reader.getContext(),
-              Reader.ReadAPFloat(Record, E->getSemantics(), Idx));
-  E->setLocation(ReadSourceLocation(Record, Idx));
+  E->setRawSemantics(static_cast<Stmt::APFloatSemantics>(Record.readInt()));
+  E->setExact(Record.readInt());
+  E->setValue(Record.getContext(), Record.readAPFloat(E->getSemantics()));
+  E->setLocation(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitImaginaryLiteral(ImaginaryLiteral *E) {
   VisitExpr(E);
-  E->setSubExpr(Reader.ReadSubExpr());
+  E->setSubExpr(Record.readSubExpr());
 }
 
 void ASTStmtReader::VisitStringLiteral(StringLiteral *E) {
   VisitExpr(E);
-  unsigned Len = Record[Idx++];
-  assert(Record[Idx] == E->getNumConcatenated() &&
+  unsigned Len = Record.readInt();
+  assert(Record.peekInt() == E->getNumConcatenated() &&
          "Wrong number of concatenated tokens!");
-  ++Idx;
+  Record.skipInts(1);
   StringLiteral::StringKind kind =
-        static_cast<StringLiteral::StringKind>(Record[Idx++]);
-  bool isPascal = Record[Idx++];
+        static_cast<StringLiteral::StringKind>(Record.readInt());
+  bool isPascal = Record.readInt();
 
   // Read string data
-  SmallString<16> Str(&Record[Idx], &Record[Idx] + Len);
-  E->setString(Reader.getContext(), Str, kind, isPascal);
-  Idx += Len;
+  auto B = &Record.peekInt();
+  SmallString<16> Str(B, B + Len);
+  E->setString(Record.getContext(), Str, kind, isPascal);
+  Record.skipInts(Len);
 
   // Read source locations
   for (unsigned I = 0, N = E->getNumConcatenated(); I != N; ++I)
-    E->setStrTokenLoc(I, ReadSourceLocation(Record, Idx));
+    E->setStrTokenLoc(I, ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitCharacterLiteral(CharacterLiteral *E) {
   VisitExpr(E);
-  E->setValue(Record[Idx++]);
-  E->setLocation(ReadSourceLocation(Record, Idx));
-  E->setKind(static_cast<CharacterLiteral::CharacterKind>(Record[Idx++]));
+  E->setValue(Record.readInt());
+  E->setLocation(ReadSourceLocation());
+  E->setKind(static_cast<CharacterLiteral::CharacterKind>(Record.readInt()));
 }
 
 void ASTStmtReader::VisitParenExpr(ParenExpr *E) {
   VisitExpr(E);
-  E->setLParen(ReadSourceLocation(Record, Idx));
-  E->setRParen(ReadSourceLocation(Record, Idx));
-  E->setSubExpr(Reader.ReadSubExpr());
+  E->setLParen(ReadSourceLocation());
+  E->setRParen(ReadSourceLocation());
+  E->setSubExpr(Record.readSubExpr());
 }
 
 void ASTStmtReader::VisitParenListExpr(ParenListExpr *E) {
   VisitExpr(E);
-  unsigned NumExprs = Record[Idx++];
-  E->Exprs = new (Reader.getContext()) Stmt*[NumExprs];
+  unsigned NumExprs = Record.readInt();
+  E->Exprs = new (Record.getContext()) Stmt*[NumExprs];
   for (unsigned i = 0; i != NumExprs; ++i)
-    E->Exprs[i] = Reader.ReadSubStmt();
+    E->Exprs[i] = Record.readSubStmt();
   E->NumExprs = NumExprs;
-  E->LParenLoc = ReadSourceLocation(Record, Idx);
-  E->RParenLoc = ReadSourceLocation(Record, Idx);
+  E->LParenLoc = ReadSourceLocation();
+  E->RParenLoc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitUnaryOperator(UnaryOperator *E) {
   VisitExpr(E);
-  E->setSubExpr(Reader.ReadSubExpr());
-  E->setOpcode((UnaryOperator::Opcode)Record[Idx++]);
-  E->setOperatorLoc(ReadSourceLocation(Record, Idx));
+  E->setSubExpr(Record.readSubExpr());
+  E->setOpcode((UnaryOperator::Opcode)Record.readInt());
+  E->setOperatorLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitOffsetOfExpr(OffsetOfExpr *E) {
   VisitExpr(E);
-  assert(E->getNumComponents() == Record[Idx]);
-  ++Idx;
-  assert(E->getNumExpressions() == Record[Idx]);
-  ++Idx;
-  E->setOperatorLoc(ReadSourceLocation(Record, Idx));
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
-  E->setTypeSourceInfo(GetTypeSourceInfo(Record, Idx));
+  assert(E->getNumComponents() == Record.peekInt());
+  Record.skipInts(1);
+  assert(E->getNumExpressions() == Record.peekInt());
+  Record.skipInts(1);
+  E->setOperatorLoc(ReadSourceLocation());
+  E->setRParenLoc(ReadSourceLocation());
+  E->setTypeSourceInfo(GetTypeSourceInfo());
   for (unsigned I = 0, N = E->getNumComponents(); I != N; ++I) {
-    OffsetOfNode::Kind Kind = static_cast<OffsetOfNode::Kind>(Record[Idx++]);
-    SourceLocation Start = ReadSourceLocation(Record, Idx);
-    SourceLocation End = ReadSourceLocation(Record, Idx);
+    OffsetOfNode::Kind Kind = static_cast<OffsetOfNode::Kind>(Record.readInt());
+    SourceLocation Start = ReadSourceLocation();
+    SourceLocation End = ReadSourceLocation();
     switch (Kind) {
     case OffsetOfNode::Array:
-      E->setComponent(I, OffsetOfNode(Start, Record[Idx++], End));
+      E->setComponent(I, OffsetOfNode(Start, Record.readInt(), End));
       break;
 
     case OffsetOfNode::Field:
       E->setComponent(
-          I, OffsetOfNode(Start, ReadDeclAs<FieldDecl>(Record, Idx), End));
+          I, OffsetOfNode(Start, ReadDeclAs<FieldDecl>(), End));
       break;
 
     case OffsetOfNode::Identifier:
       E->setComponent(
           I,
-          OffsetOfNode(Start, Reader.GetIdentifierInfo(F, Record, Idx), End));
+          OffsetOfNode(Start, Record.getIdentifierInfo(), End));
       break;
 
     case OffsetOfNode::Base: {
-      CXXBaseSpecifier *Base = new (Reader.getContext()) CXXBaseSpecifier();
-      *Base = Reader.ReadCXXBaseSpecifier(F, Record, Idx);
+      CXXBaseSpecifier *Base = new (Record.getContext()) CXXBaseSpecifier();
+      *Base = Record.readCXXBaseSpecifier();
       E->setComponent(I, OffsetOfNode(Base));
       break;
     }
     }
   }
-  
+
   for (unsigned I = 0, N = E->getNumExpressions(); I != N; ++I)
-    E->setIndexExpr(I, Reader.ReadSubExpr());
+    E->setIndexExpr(I, Record.readSubExpr());
 }
 
 void ASTStmtReader::VisitUnaryExprOrTypeTraitExpr(UnaryExprOrTypeTraitExpr *E) {
   VisitExpr(E);
-  E->setKind(static_cast<UnaryExprOrTypeTrait>(Record[Idx++]));
-  if (Record[Idx] == 0) {
-    E->setArgument(Reader.ReadSubExpr());
-    ++Idx;
+  E->setKind(static_cast<UnaryExprOrTypeTrait>(Record.readInt()));
+  if (Record.peekInt() == 0) {
+    E->setArgument(Record.readSubExpr());
+    Record.skipInts(1);
   } else {
-    E->setArgument(GetTypeSourceInfo(Record, Idx));
+    E->setArgument(GetTypeSourceInfo());
   }
-  E->setOperatorLoc(ReadSourceLocation(Record, Idx));
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
+  E->setOperatorLoc(ReadSourceLocation());
+  E->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
   VisitExpr(E);
-  E->setLHS(Reader.ReadSubExpr());
-  E->setRHS(Reader.ReadSubExpr());
-  E->setRBracketLoc(ReadSourceLocation(Record, Idx));
+  E->setLHS(Record.readSubExpr());
+  E->setRHS(Record.readSubExpr());
+  E->setRBracketLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitOMPArraySectionExpr(OMPArraySectionExpr *E) {
   VisitExpr(E);
-  E->setBase(Reader.ReadSubExpr());
-  E->setLowerBound(Reader.ReadSubExpr());
-  E->setLength(Reader.ReadSubExpr());
-  E->setColonLoc(ReadSourceLocation(Record, Idx));
-  E->setRBracketLoc(ReadSourceLocation(Record, Idx));
+  E->setBase(Record.readSubExpr());
+  E->setLowerBound(Record.readSubExpr());
+  E->setLength(Record.readSubExpr());
+  E->setColonLoc(ReadSourceLocation());
+  E->setRBracketLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitCallExpr(CallExpr *E) {
   VisitExpr(E);
-  E->setNumArgs(Reader.getContext(), Record[Idx++]);
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
-  E->setCallee(Reader.ReadSubExpr());
+  E->setNumArgs(Record.getContext(), Record.readInt());
+  E->setRParenLoc(ReadSourceLocation());
+  E->setCallee(Record.readSubExpr());
   for (unsigned I = 0, N = E->getNumArgs(); I != N; ++I)
-    E->setArg(I, Reader.ReadSubExpr());
+    E->setArg(I, Record.readSubExpr());
 }
 
 void ASTStmtReader::VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
@@ -644,74 +625,74 @@ void ASTStmtReader::VisitMemberExpr(MemberExpr *E) {
 
 void ASTStmtReader::VisitObjCIsaExpr(ObjCIsaExpr *E) {
   VisitExpr(E);
-  E->setBase(Reader.ReadSubExpr());
-  E->setIsaMemberLoc(ReadSourceLocation(Record, Idx));
-  E->setOpLoc(ReadSourceLocation(Record, Idx));
-  E->setArrow(Record[Idx++]);
+  E->setBase(Record.readSubExpr());
+  E->setIsaMemberLoc(ReadSourceLocation());
+  E->setOpLoc(ReadSourceLocation());
+  E->setArrow(Record.readInt());
 }
 
 void ASTStmtReader::
 VisitObjCIndirectCopyRestoreExpr(ObjCIndirectCopyRestoreExpr *E) {
   VisitExpr(E);
-  E->Operand = Reader.ReadSubExpr();
-  E->setShouldCopy(Record[Idx++]);
+  E->Operand = Record.readSubExpr();
+  E->setShouldCopy(Record.readInt());
 }
 
 void ASTStmtReader::VisitObjCBridgedCastExpr(ObjCBridgedCastExpr *E) {
   VisitExplicitCastExpr(E);
-  E->LParenLoc = ReadSourceLocation(Record, Idx);
-  E->BridgeKeywordLoc = ReadSourceLocation(Record, Idx);
-  E->Kind = Record[Idx++];
+  E->LParenLoc = ReadSourceLocation();
+  E->BridgeKeywordLoc = ReadSourceLocation();
+  E->Kind = Record.readInt();
 }
 
 void ASTStmtReader::VisitCastExpr(CastExpr *E) {
   VisitExpr(E);
-  unsigned NumBaseSpecs = Record[Idx++];
+  unsigned NumBaseSpecs = Record.readInt();
   assert(NumBaseSpecs == E->path_size());
-  E->setSubExpr(Reader.ReadSubExpr());
-  E->setCastKind((CastKind)Record[Idx++]);
+  E->setSubExpr(Record.readSubExpr());
+  E->setCastKind((CastKind)Record.readInt());
   CastExpr::path_iterator BaseI = E->path_begin();
   while (NumBaseSpecs--) {
-    CXXBaseSpecifier *BaseSpec = new (Reader.getContext()) CXXBaseSpecifier;
-    *BaseSpec = Reader.ReadCXXBaseSpecifier(F, Record, Idx);
+    CXXBaseSpecifier *BaseSpec = new (Record.getContext()) CXXBaseSpecifier;
+    *BaseSpec = Record.readCXXBaseSpecifier();
     *BaseI++ = BaseSpec;
   }
 }
 
 void ASTStmtReader::VisitBinaryOperator(BinaryOperator *E) {
   VisitExpr(E);
-  E->setLHS(Reader.ReadSubExpr());
-  E->setRHS(Reader.ReadSubExpr());
-  E->setOpcode((BinaryOperator::Opcode)Record[Idx++]);
-  E->setOperatorLoc(ReadSourceLocation(Record, Idx));
-  E->setFPContractable((bool)Record[Idx++]);
+  E->setLHS(Record.readSubExpr());
+  E->setRHS(Record.readSubExpr());
+  E->setOpcode((BinaryOperator::Opcode)Record.readInt());
+  E->setOperatorLoc(ReadSourceLocation());
+  E->setFPContractable((bool)Record.readInt());
 }
 
 void ASTStmtReader::VisitCompoundAssignOperator(CompoundAssignOperator *E) {
   VisitBinaryOperator(E);
-  E->setComputationLHSType(Reader.readType(F, Record, Idx));
-  E->setComputationResultType(Reader.readType(F, Record, Idx));
+  E->setComputationLHSType(Record.readType());
+  E->setComputationResultType(Record.readType());
 }
 
 void ASTStmtReader::VisitConditionalOperator(ConditionalOperator *E) {
   VisitExpr(E);
-  E->SubExprs[ConditionalOperator::COND] = Reader.ReadSubExpr();
-  E->SubExprs[ConditionalOperator::LHS] = Reader.ReadSubExpr();
-  E->SubExprs[ConditionalOperator::RHS] = Reader.ReadSubExpr();
-  E->QuestionLoc = ReadSourceLocation(Record, Idx);
-  E->ColonLoc = ReadSourceLocation(Record, Idx);
+  E->SubExprs[ConditionalOperator::COND] = Record.readSubExpr();
+  E->SubExprs[ConditionalOperator::LHS] = Record.readSubExpr();
+  E->SubExprs[ConditionalOperator::RHS] = Record.readSubExpr();
+  E->QuestionLoc = ReadSourceLocation();
+  E->ColonLoc = ReadSourceLocation();
 }
 
 void
 ASTStmtReader::VisitBinaryConditionalOperator(BinaryConditionalOperator *E) {
   VisitExpr(E);
-  E->OpaqueValue = cast<OpaqueValueExpr>(Reader.ReadSubExpr());
-  E->SubExprs[BinaryConditionalOperator::COMMON] = Reader.ReadSubExpr();
-  E->SubExprs[BinaryConditionalOperator::COND] = Reader.ReadSubExpr();
-  E->SubExprs[BinaryConditionalOperator::LHS] = Reader.ReadSubExpr();
-  E->SubExprs[BinaryConditionalOperator::RHS] = Reader.ReadSubExpr();
-  E->QuestionLoc = ReadSourceLocation(Record, Idx);
-  E->ColonLoc = ReadSourceLocation(Record, Idx);
+  E->OpaqueValue = cast<OpaqueValueExpr>(Record.readSubExpr());
+  E->SubExprs[BinaryConditionalOperator::COMMON] = Record.readSubExpr();
+  E->SubExprs[BinaryConditionalOperator::COND] = Record.readSubExpr();
+  E->SubExprs[BinaryConditionalOperator::LHS] = Record.readSubExpr();
+  E->SubExprs[BinaryConditionalOperator::RHS] = Record.readSubExpr();
+  E->QuestionLoc = ReadSourceLocation();
+  E->ColonLoc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitImplicitCastExpr(ImplicitCastExpr *E) {
@@ -720,54 +701,54 @@ void ASTStmtReader::VisitImplicitCastExpr(ImplicitCastExpr *E) {
 
 void ASTStmtReader::VisitExplicitCastExpr(ExplicitCastExpr *E) {
   VisitCastExpr(E);
-  E->setTypeInfoAsWritten(GetTypeSourceInfo(Record, Idx));
+  E->setTypeInfoAsWritten(GetTypeSourceInfo());
 }
 
 void ASTStmtReader::VisitCStyleCastExpr(CStyleCastExpr *E) {
   VisitExplicitCastExpr(E);
-  E->setLParenLoc(ReadSourceLocation(Record, Idx));
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
+  E->setLParenLoc(ReadSourceLocation());
+  E->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
   VisitExpr(E);
-  E->setLParenLoc(ReadSourceLocation(Record, Idx));
-  E->setTypeSourceInfo(GetTypeSourceInfo(Record, Idx));
-  E->setInitializer(Reader.ReadSubExpr());
-  E->setFileScope(Record[Idx++]);
+  E->setLParenLoc(ReadSourceLocation());
+  E->setTypeSourceInfo(GetTypeSourceInfo());
+  E->setInitializer(Record.readSubExpr());
+  E->setFileScope(Record.readInt());
 }
 
 void ASTStmtReader::VisitExtVectorElementExpr(ExtVectorElementExpr *E) {
   VisitExpr(E);
-  E->setBase(Reader.ReadSubExpr());
-  E->setAccessor(Reader.GetIdentifierInfo(F, Record, Idx));
-  E->setAccessorLoc(ReadSourceLocation(Record, Idx));
+  E->setBase(Record.readSubExpr());
+  E->setAccessor(Record.getIdentifierInfo());
+  E->setAccessorLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitInitListExpr(InitListExpr *E) {
   VisitExpr(E);
-  if (InitListExpr *SyntForm = cast_or_null<InitListExpr>(Reader.ReadSubStmt()))
+  if (InitListExpr *SyntForm = cast_or_null<InitListExpr>(Record.readSubStmt()))
     E->setSyntacticForm(SyntForm);
-  E->setLBraceLoc(ReadSourceLocation(Record, Idx));
-  E->setRBraceLoc(ReadSourceLocation(Record, Idx));
-  bool isArrayFiller = Record[Idx++];
+  E->setLBraceLoc(ReadSourceLocation());
+  E->setRBraceLoc(ReadSourceLocation());
+  bool isArrayFiller = Record.readInt();
   Expr *filler = nullptr;
   if (isArrayFiller) {
-    filler = Reader.ReadSubExpr();
+    filler = Record.readSubExpr();
     E->ArrayFillerOrUnionFieldInit = filler;
   } else
-    E->ArrayFillerOrUnionFieldInit = ReadDeclAs<FieldDecl>(Record, Idx);
-  E->sawArrayRangeDesignator(Record[Idx++]);
-  unsigned NumInits = Record[Idx++];
-  E->reserveInits(Reader.getContext(), NumInits);
+    E->ArrayFillerOrUnionFieldInit = ReadDeclAs<FieldDecl>();
+  E->sawArrayRangeDesignator(Record.readInt());
+  unsigned NumInits = Record.readInt();
+  E->reserveInits(Record.getContext(), NumInits);
   if (isArrayFiller) {
     for (unsigned I = 0; I != NumInits; ++I) {
-      Expr *init = Reader.ReadSubExpr();
-      E->updateInit(Reader.getContext(), I, init ? init : filler);
+      Expr *init = Record.readSubExpr();
+      E->updateInit(Record.getContext(), I, init ? init : filler);
     }
   } else {
     for (unsigned I = 0; I != NumInits; ++I)
-      E->updateInit(Reader.getContext(), I, Reader.ReadSubExpr());
+      E->updateInit(Record.getContext(), I, Record.readSubExpr());
   }
 }
 
@@ -775,22 +756,20 @@ void ASTStmtReader::VisitDesignatedInitExpr(DesignatedInitExpr *E) {
   typedef DesignatedInitExpr::Designator Designator;
 
   VisitExpr(E);
-  unsigned NumSubExprs = Record[Idx++];
+  unsigned NumSubExprs = Record.readInt();
   assert(NumSubExprs == E->getNumSubExprs() && "Wrong number of subexprs");
   for (unsigned I = 0; I != NumSubExprs; ++I)
-    E->setSubExpr(I, Reader.ReadSubExpr());
-  E->setEqualOrColonLoc(ReadSourceLocation(Record, Idx));
-  E->setGNUSyntax(Record[Idx++]);
+    E->setSubExpr(I, Record.readSubExpr());
+  E->setEqualOrColonLoc(ReadSourceLocation());
+  E->setGNUSyntax(Record.readInt());
 
   SmallVector<Designator, 4> Designators;
-  while (Idx < Record.size()) {
-    switch ((DesignatorTypes)Record[Idx++]) {
+  while (Record.getIdx() < Record.size()) {
+    switch ((DesignatorTypes)Record.readInt()) {
     case DESIG_FIELD_DECL: {
-      FieldDecl *Field = ReadDeclAs<FieldDecl>(Record, Idx);
-      SourceLocation DotLoc
-        = ReadSourceLocation(Record, Idx);
-      SourceLocation FieldLoc
-        = ReadSourceLocation(Record, Idx);
+      FieldDecl *Field = ReadDeclAs<FieldDecl>();
+      SourceLocation DotLoc = ReadSourceLocation();
+      SourceLocation FieldLoc = ReadSourceLocation();
       Designators.push_back(Designator(Field->getIdentifier(), DotLoc,
                                        FieldLoc));
       Designators.back().setField(Field);
@@ -798,162 +777,165 @@ void ASTStmtReader::VisitDesignatedInitExpr(DesignatedInitExpr *E) {
     }
 
     case DESIG_FIELD_NAME: {
-      const IdentifierInfo *Name = Reader.GetIdentifierInfo(F, Record, Idx);
-      SourceLocation DotLoc
-        = ReadSourceLocation(Record, Idx);
-      SourceLocation FieldLoc
-        = ReadSourceLocation(Record, Idx);
+      const IdentifierInfo *Name = Record.getIdentifierInfo();
+      SourceLocation DotLoc = ReadSourceLocation();
+      SourceLocation FieldLoc = ReadSourceLocation();
       Designators.push_back(Designator(Name, DotLoc, FieldLoc));
       break;
     }
 
     case DESIG_ARRAY: {
-      unsigned Index = Record[Idx++];
-      SourceLocation LBracketLoc
-        = ReadSourceLocation(Record, Idx);
-      SourceLocation RBracketLoc
-        = ReadSourceLocation(Record, Idx);
+      unsigned Index = Record.readInt();
+      SourceLocation LBracketLoc = ReadSourceLocation();
+      SourceLocation RBracketLoc = ReadSourceLocation();
       Designators.push_back(Designator(Index, LBracketLoc, RBracketLoc));
       break;
     }
 
     case DESIG_ARRAY_RANGE: {
-      unsigned Index = Record[Idx++];
-      SourceLocation LBracketLoc
-        = ReadSourceLocation(Record, Idx);
-      SourceLocation EllipsisLoc
-        = ReadSourceLocation(Record, Idx);
-      SourceLocation RBracketLoc
-        = ReadSourceLocation(Record, Idx);
+      unsigned Index = Record.readInt();
+      SourceLocation LBracketLoc = ReadSourceLocation();
+      SourceLocation EllipsisLoc = ReadSourceLocation();
+      SourceLocation RBracketLoc = ReadSourceLocation();
       Designators.push_back(Designator(Index, LBracketLoc, EllipsisLoc,
                                        RBracketLoc));
       break;
     }
     }
   }
-  E->setDesignators(Reader.getContext(), 
+  E->setDesignators(Record.getContext(),
                     Designators.data(), Designators.size());
 }
 
 void ASTStmtReader::VisitDesignatedInitUpdateExpr(DesignatedInitUpdateExpr *E) {
   VisitExpr(E);
-  E->setBase(Reader.ReadSubExpr());
-  E->setUpdater(Reader.ReadSubExpr());
+  E->setBase(Record.readSubExpr());
+  E->setUpdater(Record.readSubExpr());
 }
 
 void ASTStmtReader::VisitNoInitExpr(NoInitExpr *E) {
   VisitExpr(E);
 }
 
+void ASTStmtReader::VisitArrayInitLoopExpr(ArrayInitLoopExpr *E) {
+  VisitExpr(E);
+  E->SubExprs[0] = Record.readSubExpr();
+  E->SubExprs[1] = Record.readSubExpr();
+}
+
+void ASTStmtReader::VisitArrayInitIndexExpr(ArrayInitIndexExpr *E) {
+  VisitExpr(E);
+}
+
 void ASTStmtReader::VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
   VisitExpr(E);
 }
 
 void ASTStmtReader::VisitVAArgExpr(VAArgExpr *E) {
   VisitExpr(E);
-  E->setSubExpr(Reader.ReadSubExpr());
-  E->setWrittenTypeInfo(GetTypeSourceInfo(Record, Idx));
-  E->setBuiltinLoc(ReadSourceLocation(Record, Idx));
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
-  E->setIsMicrosoftABI(Record[Idx++]);
+  E->setSubExpr(Record.readSubExpr());
+  E->setWrittenTypeInfo(GetTypeSourceInfo());
+  E->setBuiltinLoc(ReadSourceLocation());
+  E->setRParenLoc(ReadSourceLocation());
+  E->setIsMicrosoftABI(Record.readInt());
 }
 
 void ASTStmtReader::VisitAddrLabelExpr(AddrLabelExpr *E) {
   VisitExpr(E);
-  E->setAmpAmpLoc(ReadSourceLocation(Record, Idx));
-  E->setLabelLoc(ReadSourceLocation(Record, Idx));
-  E->setLabel(ReadDeclAs<LabelDecl>(Record, Idx));
+  E->setAmpAmpLoc(ReadSourceLocation());
+  E->setLabelLoc(ReadSourceLocation());
+  E->setLabel(ReadDeclAs<LabelDecl>());
 }
 
 void ASTStmtReader::VisitStmtExpr(StmtExpr *E) {
   VisitExpr(E);
-  E->setLParenLoc(ReadSourceLocation(Record, Idx));
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
-  E->setSubStmt(cast_or_null<CompoundStmt>(Reader.ReadSubStmt()));
+  E->setLParenLoc(ReadSourceLocation());
+  E->setRParenLoc(ReadSourceLocation());
+  E->setSubStmt(cast_or_null<CompoundStmt>(Record.readSubStmt()));
 }
 
 void ASTStmtReader::VisitChooseExpr(ChooseExpr *E) {
   VisitExpr(E);
-  E->setCond(Reader.ReadSubExpr());
-  E->setLHS(Reader.ReadSubExpr());
-  E->setRHS(Reader.ReadSubExpr());
-  E->setBuiltinLoc(ReadSourceLocation(Record, Idx));
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
-  E->setIsConditionTrue(Record[Idx++]);
+  E->setCond(Record.readSubExpr());
+  E->setLHS(Record.readSubExpr());
+  E->setRHS(Record.readSubExpr());
+  E->setBuiltinLoc(ReadSourceLocation());
+  E->setRParenLoc(ReadSourceLocation());
+  E->setIsConditionTrue(Record.readInt());
 }
 
 void ASTStmtReader::VisitGNUNullExpr(GNUNullExpr *E) {
   VisitExpr(E);
-  E->setTokenLocation(ReadSourceLocation(Record, Idx));
+  E->setTokenLocation(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitShuffleVectorExpr(ShuffleVectorExpr *E) {
   VisitExpr(E);
   SmallVector<Expr *, 16> Exprs;
-  unsigned NumExprs = Record[Idx++];
+  unsigned NumExprs = Record.readInt();
   while (NumExprs--)
-    Exprs.push_back(Reader.ReadSubExpr());
-  E->setExprs(Reader.getContext(), Exprs);
-  E->setBuiltinLoc(ReadSourceLocation(Record, Idx));
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
+    Exprs.push_back(Record.readSubExpr());
+  E->setExprs(Record.getContext(), Exprs);
+  E->setBuiltinLoc(ReadSourceLocation());
+  E->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitConvertVectorExpr(ConvertVectorExpr *E) {
   VisitExpr(E);
-  E->BuiltinLoc = ReadSourceLocation(Record, Idx);
-  E->RParenLoc = ReadSourceLocation(Record, Idx);
-  E->TInfo = GetTypeSourceInfo(Record, Idx);
-  E->SrcExpr = Reader.ReadSubExpr();
+  E->BuiltinLoc = ReadSourceLocation();
+  E->RParenLoc = ReadSourceLocation();
+  E->TInfo = GetTypeSourceInfo();
+  E->SrcExpr = Record.readSubExpr();
 }
 
 void ASTStmtReader::VisitBlockExpr(BlockExpr *E) {
   VisitExpr(E);
-  E->setBlockDecl(ReadDeclAs<BlockDecl>(Record, Idx));
+  E->setBlockDecl(ReadDeclAs<BlockDecl>());
 }
 
 void ASTStmtReader::VisitGenericSelectionExpr(GenericSelectionExpr *E) {
   VisitExpr(E);
-  E->NumAssocs = Record[Idx++];
-  E->AssocTypes = new (Reader.getContext()) TypeSourceInfo*[E->NumAssocs];
+  E->NumAssocs = Record.readInt();
+  E->AssocTypes = new (Record.getContext()) TypeSourceInfo*[E->NumAssocs];
   E->SubExprs =
-   new(Reader.getContext()) Stmt*[GenericSelectionExpr::END_EXPR+E->NumAssocs];
+   new(Record.getContext()) Stmt*[GenericSelectionExpr::END_EXPR+E->NumAssocs];
 
-  E->SubExprs[GenericSelectionExpr::CONTROLLING] = Reader.ReadSubExpr();
+  E->SubExprs[GenericSelectionExpr::CONTROLLING] = Record.readSubExpr();
   for (unsigned I = 0, N = E->getNumAssocs(); I != N; ++I) {
-    E->AssocTypes[I] = GetTypeSourceInfo(Record, Idx);
-    E->SubExprs[GenericSelectionExpr::END_EXPR+I] = Reader.ReadSubExpr();
+    E->AssocTypes[I] = GetTypeSourceInfo();
+    E->SubExprs[GenericSelectionExpr::END_EXPR+I] = Record.readSubExpr();
   }
-  E->ResultIndex = Record[Idx++];
+  E->ResultIndex = Record.readInt();
 
-  E->GenericLoc = ReadSourceLocation(Record, Idx);
-  E->DefaultLoc = ReadSourceLocation(Record, Idx);
-  E->RParenLoc = ReadSourceLocation(Record, Idx);
+  E->GenericLoc = ReadSourceLocation();
+  E->DefaultLoc = ReadSourceLocation();
+  E->RParenLoc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitPseudoObjectExpr(PseudoObjectExpr *E) {
   VisitExpr(E);
-  unsigned numSemanticExprs = Record[Idx++];
+  unsigned numSemanticExprs = Record.readInt();
   assert(numSemanticExprs + 1 == E->PseudoObjectExprBits.NumSubExprs);
-  E->PseudoObjectExprBits.ResultIndex = Record[Idx++];
+  E->PseudoObjectExprBits.ResultIndex = Record.readInt();
 
   // Read the syntactic expression.
-  E->getSubExprsBuffer()[0] = Reader.ReadSubExpr();
+  E->getSubExprsBuffer()[0] = Record.readSubExpr();
 
   // Read all the semantic expressions.
   for (unsigned i = 0; i != numSemanticExprs; ++i) {
-    Expr *subExpr = Reader.ReadSubExpr();
+    Expr *subExpr = Record.readSubExpr();
     E->getSubExprsBuffer()[i+1] = subExpr;
   }
 }
 
 void ASTStmtReader::VisitAtomicExpr(AtomicExpr *E) {
   VisitExpr(E);
-  E->Op = AtomicExpr::AtomicOp(Record[Idx++]);
+  E->Op = AtomicExpr::AtomicOp(Record.readInt());
   E->NumSubExprs = AtomicExpr::getNumSubExprs(E->Op);
   for (unsigned I = 0; I != E->NumSubExprs; ++I)
-    E->SubExprs[I] = Reader.ReadSubExpr();
-  E->BuiltinLoc = ReadSourceLocation(Record, Idx);
-  E->RParenLoc = ReadSourceLocation(Record, Idx);
+    E->SubExprs[I] = Record.readSubExpr();
+  E->BuiltinLoc = ReadSourceLocation();
+  E->RParenLoc = ReadSourceLocation();
 }
 
 //===----------------------------------------------------------------------===//
@@ -961,142 +943,141 @@ void ASTStmtReader::VisitAtomicExpr(AtomicExpr *E) {
 
 void ASTStmtReader::VisitObjCStringLiteral(ObjCStringLiteral *E) {
   VisitExpr(E);
-  E->setString(cast<StringLiteral>(Reader.ReadSubStmt()));
-  E->setAtLoc(ReadSourceLocation(Record, Idx));
+  E->setString(cast<StringLiteral>(Record.readSubStmt()));
+  E->setAtLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCBoxedExpr(ObjCBoxedExpr *E) {
   VisitExpr(E);
   // could be one of several IntegerLiteral, FloatLiteral, etc.
-  E->SubExpr = Reader.ReadSubStmt();
-  E->BoxingMethod = ReadDeclAs<ObjCMethodDecl>(Record, Idx);
-  E->Range = ReadSourceRange(Record, Idx);
+  E->SubExpr = Record.readSubStmt();
+  E->BoxingMethod = ReadDeclAs<ObjCMethodDecl>();
+  E->Range = ReadSourceRange();
 }
 
 void ASTStmtReader::VisitObjCArrayLiteral(ObjCArrayLiteral *E) {
   VisitExpr(E);
-  unsigned NumElements = Record[Idx++];
+  unsigned NumElements = Record.readInt();
   assert(NumElements == E->getNumElements() && "Wrong number of elements");
   Expr **Elements = E->getElements();
   for (unsigned I = 0, N = NumElements; I != N; ++I)
-    Elements[I] = Reader.ReadSubExpr();
-  E->ArrayWithObjectsMethod = ReadDeclAs<ObjCMethodDecl>(Record, Idx);
-  E->Range = ReadSourceRange(Record, Idx);
+    Elements[I] = Record.readSubExpr();
+  E->ArrayWithObjectsMethod = ReadDeclAs<ObjCMethodDecl>();
+  E->Range = ReadSourceRange();
 }
 
 void ASTStmtReader::VisitObjCDictionaryLiteral(ObjCDictionaryLiteral *E) {
   VisitExpr(E);
-  unsigned NumElements = Record[Idx++];
+  unsigned NumElements = Record.readInt();
   assert(NumElements == E->getNumElements() && "Wrong number of elements");
-  bool HasPackExpansions = Record[Idx++];
+  bool HasPackExpansions = Record.readInt();
   assert(HasPackExpansions == E->HasPackExpansions &&"Pack expansion mismatch");
   ObjCDictionaryLiteral::KeyValuePair *KeyValues =
       E->getTrailingObjects<ObjCDictionaryLiteral::KeyValuePair>();
   ObjCDictionaryLiteral::ExpansionData *Expansions =
       E->getTrailingObjects<ObjCDictionaryLiteral::ExpansionData>();
   for (unsigned I = 0; I != NumElements; ++I) {
-    KeyValues[I].Key = Reader.ReadSubExpr();
-    KeyValues[I].Value = Reader.ReadSubExpr();
+    KeyValues[I].Key = Record.readSubExpr();
+    KeyValues[I].Value = Record.readSubExpr();
     if (HasPackExpansions) {
-      Expansions[I].EllipsisLoc = ReadSourceLocation(Record, Idx);
-      Expansions[I].NumExpansionsPlusOne = Record[Idx++];
+      Expansions[I].EllipsisLoc = ReadSourceLocation();
+      Expansions[I].NumExpansionsPlusOne = Record.readInt();
     }
   }
-  E->DictWithObjectsMethod = ReadDeclAs<ObjCMethodDecl>(Record, Idx);
-  E->Range = ReadSourceRange(Record, Idx);
+  E->DictWithObjectsMethod = ReadDeclAs<ObjCMethodDecl>();
+  E->Range = ReadSourceRange();
 }
 
 void ASTStmtReader::VisitObjCEncodeExpr(ObjCEncodeExpr *E) {
   VisitExpr(E);
-  E->setEncodedTypeSourceInfo(GetTypeSourceInfo(Record, Idx));
-  E->setAtLoc(ReadSourceLocation(Record, Idx));
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
+  E->setEncodedTypeSourceInfo(GetTypeSourceInfo());
+  E->setAtLoc(ReadSourceLocation());
+  E->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCSelectorExpr(ObjCSelectorExpr *E) {
   VisitExpr(E);
-  E->setSelector(Reader.ReadSelector(F, Record, Idx));
-  E->setAtLoc(ReadSourceLocation(Record, Idx));
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
+  E->setSelector(Record.readSelector());
+  E->setAtLoc(ReadSourceLocation());
+  E->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCProtocolExpr(ObjCProtocolExpr *E) {
   VisitExpr(E);
-  E->setProtocol(ReadDeclAs<ObjCProtocolDecl>(Record, Idx));
-  E->setAtLoc(ReadSourceLocation(Record, Idx));
-  E->ProtoLoc = ReadSourceLocation(Record, Idx);
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
+  E->setProtocol(ReadDeclAs<ObjCProtocolDecl>());
+  E->setAtLoc(ReadSourceLocation());
+  E->ProtoLoc = ReadSourceLocation();
+  E->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
   VisitExpr(E);
-  E->setDecl(ReadDeclAs<ObjCIvarDecl>(Record, Idx));
-  E->setLocation(ReadSourceLocation(Record, Idx));
-  E->setOpLoc(ReadSourceLocation(Record, Idx));
-  E->setBase(Reader.ReadSubExpr());
-  E->setIsArrow(Record[Idx++]);
-  E->setIsFreeIvar(Record[Idx++]);
+  E->setDecl(ReadDeclAs<ObjCIvarDecl>());
+  E->setLocation(ReadSourceLocation());
+  E->setOpLoc(ReadSourceLocation());
+  E->setBase(Record.readSubExpr());
+  E->setIsArrow(Record.readInt());
+  E->setIsFreeIvar(Record.readInt());
 }
 
 void ASTStmtReader::VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) {
   VisitExpr(E);
-  unsigned MethodRefFlags = Record[Idx++];
-  bool Implicit = Record[Idx++] != 0;
+  unsigned MethodRefFlags = Record.readInt();
+  bool Implicit = Record.readInt() != 0;
   if (Implicit) {
-    ObjCMethodDecl *Getter = ReadDeclAs<ObjCMethodDecl>(Record, Idx);
-    ObjCMethodDecl *Setter = ReadDeclAs<ObjCMethodDecl>(Record, Idx);
+    ObjCMethodDecl *Getter = ReadDeclAs<ObjCMethodDecl>();
+    ObjCMethodDecl *Setter = ReadDeclAs<ObjCMethodDecl>();
     E->setImplicitProperty(Getter, Setter, MethodRefFlags);
   } else {
-    E->setExplicitProperty(ReadDeclAs<ObjCPropertyDecl>(Record, Idx),
-                           MethodRefFlags);
+    E->setExplicitProperty(ReadDeclAs<ObjCPropertyDecl>(), MethodRefFlags);
   }
-  E->setLocation(ReadSourceLocation(Record, Idx));
-  E->setReceiverLocation(ReadSourceLocation(Record, Idx));
-  switch (Record[Idx++]) {
+  E->setLocation(ReadSourceLocation());
+  E->setReceiverLocation(ReadSourceLocation());
+  switch (Record.readInt()) {
   case 0:
-    E->setBase(Reader.ReadSubExpr());
+    E->setBase(Record.readSubExpr());
     break;
   case 1:
-    E->setSuperReceiver(Reader.readType(F, Record, Idx));
+    E->setSuperReceiver(Record.readType());
     break;
   case 2:
-    E->setClassReceiver(ReadDeclAs<ObjCInterfaceDecl>(Record, Idx));
+    E->setClassReceiver(ReadDeclAs<ObjCInterfaceDecl>());
     break;
   }
 }
 
 void ASTStmtReader::VisitObjCSubscriptRefExpr(ObjCSubscriptRefExpr *E) {
   VisitExpr(E);
-  E->setRBracket(ReadSourceLocation(Record, Idx));
-  E->setBaseExpr(Reader.ReadSubExpr());
-  E->setKeyExpr(Reader.ReadSubExpr());
-  E->GetAtIndexMethodDecl = ReadDeclAs<ObjCMethodDecl>(Record, Idx);
-  E->SetAtIndexMethodDecl = ReadDeclAs<ObjCMethodDecl>(Record, Idx);
+  E->setRBracket(ReadSourceLocation());
+  E->setBaseExpr(Record.readSubExpr());
+  E->setKeyExpr(Record.readSubExpr());
+  E->GetAtIndexMethodDecl = ReadDeclAs<ObjCMethodDecl>();
+  E->SetAtIndexMethodDecl = ReadDeclAs<ObjCMethodDecl>();
 }
 
 void ASTStmtReader::VisitObjCMessageExpr(ObjCMessageExpr *E) {
   VisitExpr(E);
-  assert(Record[Idx] == E->getNumArgs());
-  ++Idx;
-  unsigned NumStoredSelLocs = Record[Idx++];
-  E->SelLocsKind = Record[Idx++]; 
-  E->setDelegateInitCall(Record[Idx++]);
-  E->IsImplicit = Record[Idx++];
+  assert(Record.peekInt() == E->getNumArgs());
+  Record.skipInts(1);
+  unsigned NumStoredSelLocs = Record.readInt();
+  E->SelLocsKind = Record.readInt();
+  E->setDelegateInitCall(Record.readInt());
+  E->IsImplicit = Record.readInt();
   ObjCMessageExpr::ReceiverKind Kind
-    = static_cast<ObjCMessageExpr::ReceiverKind>(Record[Idx++]);
+    = static_cast<ObjCMessageExpr::ReceiverKind>(Record.readInt());
   switch (Kind) {
   case ObjCMessageExpr::Instance:
-    E->setInstanceReceiver(Reader.ReadSubExpr());
+    E->setInstanceReceiver(Record.readSubExpr());
     break;
 
   case ObjCMessageExpr::Class:
-    E->setClassReceiver(GetTypeSourceInfo(Record, Idx));
+    E->setClassReceiver(GetTypeSourceInfo());
     break;
 
   case ObjCMessageExpr::SuperClass:
   case ObjCMessageExpr::SuperInstance: {
-    QualType T = Reader.readType(F, Record, Idx);
-    SourceLocation SuperLoc = ReadSourceLocation(Record, Idx);
+    QualType T = Record.readType();
+    SourceLocation SuperLoc = ReadSourceLocation();
     E->setSuper(SuperLoc, T, Kind == ObjCMessageExpr::SuperInstance);
     break;
   }
@@ -1104,90 +1085,90 @@ void ASTStmtReader::VisitObjCMessageExpr(ObjCMessageExpr *E) {
 
   assert(Kind == E->getReceiverKind());
 
-  if (Record[Idx++])
-    E->setMethodDecl(ReadDeclAs<ObjCMethodDecl>(Record, Idx));
+  if (Record.readInt())
+    E->setMethodDecl(ReadDeclAs<ObjCMethodDecl>());
   else
-    E->setSelector(Reader.ReadSelector(F, Record, Idx));
+    E->setSelector(Record.readSelector());
 
-  E->LBracLoc = ReadSourceLocation(Record, Idx);
-  E->RBracLoc = ReadSourceLocation(Record, Idx);
+  E->LBracLoc = ReadSourceLocation();
+  E->RBracLoc = ReadSourceLocation();
 
   for (unsigned I = 0, N = E->getNumArgs(); I != N; ++I)
-    E->setArg(I, Reader.ReadSubExpr());
+    E->setArg(I, Record.readSubExpr());
 
   SourceLocation *Locs = E->getStoredSelLocs();
   for (unsigned I = 0; I != NumStoredSelLocs; ++I)
-    Locs[I] = ReadSourceLocation(Record, Idx);
+    Locs[I] = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitObjCForCollectionStmt(ObjCForCollectionStmt *S) {
   VisitStmt(S);
-  S->setElement(Reader.ReadSubStmt());
-  S->setCollection(Reader.ReadSubExpr());
-  S->setBody(Reader.ReadSubStmt());
-  S->setForLoc(ReadSourceLocation(Record, Idx));
-  S->setRParenLoc(ReadSourceLocation(Record, Idx));
+  S->setElement(Record.readSubStmt());
+  S->setCollection(Record.readSubExpr());
+  S->setBody(Record.readSubStmt());
+  S->setForLoc(ReadSourceLocation());
+  S->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCAtCatchStmt(ObjCAtCatchStmt *S) {
   VisitStmt(S);
-  S->setCatchBody(Reader.ReadSubStmt());
-  S->setCatchParamDecl(ReadDeclAs<VarDecl>(Record, Idx));
-  S->setAtCatchLoc(ReadSourceLocation(Record, Idx));
-  S->setRParenLoc(ReadSourceLocation(Record, Idx));
+  S->setCatchBody(Record.readSubStmt());
+  S->setCatchParamDecl(ReadDeclAs<VarDecl>());
+  S->setAtCatchLoc(ReadSourceLocation());
+  S->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCAtFinallyStmt(ObjCAtFinallyStmt *S) {
   VisitStmt(S);
-  S->setFinallyBody(Reader.ReadSubStmt());
-  S->setAtFinallyLoc(ReadSourceLocation(Record, Idx));
+  S->setFinallyBody(Record.readSubStmt());
+  S->setAtFinallyLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCAutoreleasePoolStmt(ObjCAutoreleasePoolStmt *S) {
   VisitStmt(S);
-  S->setSubStmt(Reader.ReadSubStmt());
-  S->setAtLoc(ReadSourceLocation(Record, Idx));
+  S->setSubStmt(Record.readSubStmt());
+  S->setAtLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCAtTryStmt(ObjCAtTryStmt *S) {
   VisitStmt(S);
-  assert(Record[Idx] == S->getNumCatchStmts());
-  ++Idx;
-  bool HasFinally = Record[Idx++];
-  S->setTryBody(Reader.ReadSubStmt());
+  assert(Record.peekInt() == S->getNumCatchStmts());
+  Record.skipInts(1);
+  bool HasFinally = Record.readInt();
+  S->setTryBody(Record.readSubStmt());
   for (unsigned I = 0, N = S->getNumCatchStmts(); I != N; ++I)
-    S->setCatchStmt(I, cast_or_null<ObjCAtCatchStmt>(Reader.ReadSubStmt()));
+    S->setCatchStmt(I, cast_or_null<ObjCAtCatchStmt>(Record.readSubStmt()));
 
   if (HasFinally)
-    S->setFinallyStmt(Reader.ReadSubStmt());
-  S->setAtTryLoc(ReadSourceLocation(Record, Idx));
+    S->setFinallyStmt(Record.readSubStmt());
+  S->setAtTryLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCAtSynchronizedStmt(ObjCAtSynchronizedStmt *S) {
   VisitStmt(S);
-  S->setSynchExpr(Reader.ReadSubStmt());
-  S->setSynchBody(Reader.ReadSubStmt());
-  S->setAtSynchronizedLoc(ReadSourceLocation(Record, Idx));
+  S->setSynchExpr(Record.readSubStmt());
+  S->setSynchBody(Record.readSubStmt());
+  S->setAtSynchronizedLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCAtThrowStmt(ObjCAtThrowStmt *S) {
   VisitStmt(S);
-  S->setThrowExpr(Reader.ReadSubStmt());
-  S->setThrowLoc(ReadSourceLocation(Record, Idx));
+  S->setThrowExpr(Record.readSubStmt());
+  S->setThrowLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCBoolLiteralExpr(ObjCBoolLiteralExpr *E) {
   VisitExpr(E);
-  E->setValue(Record[Idx++]);
-  E->setLocation(ReadSourceLocation(Record, Idx));
+  E->setValue(Record.readInt());
+  E->setLocation(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitObjCAvailabilityCheckExpr(ObjCAvailabilityCheckExpr *E) {
   VisitExpr(E);
-  SourceRange R = Reader.ReadSourceRange(F, Record, Idx);
+  SourceRange R = Record.readSourceRange();
   E->AtLoc = R.getBegin();
   E->RParen = R.getEnd();
-  E->VersionToCheck = Reader.ReadVersionTuple(Record, Idx);
+  E->VersionToCheck = Record.readVersionTuple();
 }
 
 //===----------------------------------------------------------------------===//
@@ -1196,125 +1177,113 @@ void ASTStmtReader::VisitObjCAvailabilityCheckExpr(ObjCAvailabilityCheckExpr *E)
 
 void ASTStmtReader::VisitCXXCatchStmt(CXXCatchStmt *S) {
   VisitStmt(S);
-  S->CatchLoc = ReadSourceLocation(Record, Idx);
-  S->ExceptionDecl = ReadDeclAs<VarDecl>(Record, Idx);
-  S->HandlerBlock = Reader.ReadSubStmt();
+  S->CatchLoc = ReadSourceLocation();
+  S->ExceptionDecl = ReadDeclAs<VarDecl>();
+  S->HandlerBlock = Record.readSubStmt();
 }
 
 void ASTStmtReader::VisitCXXTryStmt(CXXTryStmt *S) {
   VisitStmt(S);
-  assert(Record[Idx] == S->getNumHandlers() && "NumStmtFields is wrong ?");
-  ++Idx;
-  S->TryLoc = ReadSourceLocation(Record, Idx);
-  S->getStmts()[0] = Reader.ReadSubStmt();
+  assert(Record.peekInt() == S->getNumHandlers() && "NumStmtFields is wrong ?");
+  Record.skipInts(1);
+  S->TryLoc = ReadSourceLocation();
+  S->getStmts()[0] = Record.readSubStmt();
   for (unsigned i = 0, e = S->getNumHandlers(); i != e; ++i)
-    S->getStmts()[i + 1] = Reader.ReadSubStmt();
+    S->getStmts()[i + 1] = Record.readSubStmt();
 }
 
 void ASTStmtReader::VisitCXXForRangeStmt(CXXForRangeStmt *S) {
   VisitStmt(S);
-  S->ForLoc = ReadSourceLocation(Record, Idx);
-  S->CoawaitLoc = ReadSourceLocation(Record, Idx);
-  S->ColonLoc = ReadSourceLocation(Record, Idx);
-  S->RParenLoc = ReadSourceLocation(Record, Idx);
-  S->setRangeStmt(Reader.ReadSubStmt());
-  S->setBeginStmt(Reader.ReadSubStmt());
-  S->setEndStmt(Reader.ReadSubStmt());
-  S->setCond(Reader.ReadSubExpr());
-  S->setInc(Reader.ReadSubExpr());
-  S->setLoopVarStmt(Reader.ReadSubStmt());
-  S->setBody(Reader.ReadSubStmt());
+  S->ForLoc = ReadSourceLocation();
+  S->CoawaitLoc = ReadSourceLocation();
+  S->ColonLoc = ReadSourceLocation();
+  S->RParenLoc = ReadSourceLocation();
+  S->setRangeStmt(Record.readSubStmt());
+  S->setBeginStmt(Record.readSubStmt());
+  S->setEndStmt(Record.readSubStmt());
+  S->setCond(Record.readSubExpr());
+  S->setInc(Record.readSubExpr());
+  S->setLoopVarStmt(Record.readSubStmt());
+  S->setBody(Record.readSubStmt());
 }
 
 void ASTStmtReader::VisitMSDependentExistsStmt(MSDependentExistsStmt *S) {
   VisitStmt(S);
-  S->KeywordLoc = ReadSourceLocation(Record, Idx);
-  S->IsIfExists = Record[Idx++];
-  S->QualifierLoc = Reader.ReadNestedNameSpecifierLoc(F, Record, Idx);
-  ReadDeclarationNameInfo(S->NameInfo, Record, Idx);
-  S->SubStmt = Reader.ReadSubStmt();
+  S->KeywordLoc = ReadSourceLocation();
+  S->IsIfExists = Record.readInt();
+  S->QualifierLoc = Record.readNestedNameSpecifierLoc();
+  ReadDeclarationNameInfo(S->NameInfo);
+  S->SubStmt = Record.readSubStmt();
 }
 
 void ASTStmtReader::VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
   VisitCallExpr(E);
-  E->Operator = (OverloadedOperatorKind)Record[Idx++];
-  E->Range = Reader.ReadSourceRange(F, Record, Idx);
-  E->setFPContractable((bool)Record[Idx++]);
+  E->Operator = (OverloadedOperatorKind)Record.readInt();
+  E->Range = Record.readSourceRange();
+  E->setFPContractable((bool)Record.readInt());
 }
 
 void ASTStmtReader::VisitCXXConstructExpr(CXXConstructExpr *E) {
   VisitExpr(E);
-  E->NumArgs = Record[Idx++];
+  E->NumArgs = Record.readInt();
   if (E->NumArgs)
-    E->Args = new (Reader.getContext()) Stmt*[E->NumArgs];
+    E->Args = new (Record.getContext()) Stmt*[E->NumArgs];
   for (unsigned I = 0, N = E->getNumArgs(); I != N; ++I)
-    E->setArg(I, Reader.ReadSubExpr());
-  E->setConstructor(ReadDeclAs<CXXConstructorDecl>(Record, Idx));
-  E->setLocation(ReadSourceLocation(Record, Idx));
-  E->setElidable(Record[Idx++]);
-  E->setHadMultipleCandidates(Record[Idx++]);
-  E->setListInitialization(Record[Idx++]);
-  E->setStdInitListInitialization(Record[Idx++]);
-  E->setRequiresZeroInitialization(Record[Idx++]);
-  E->setConstructionKind((CXXConstructExpr::ConstructionKind)Record[Idx++]);
-  E->ParenOrBraceRange = ReadSourceRange(Record, Idx);
+    E->setArg(I, Record.readSubExpr());
+  E->setConstructor(ReadDeclAs<CXXConstructorDecl>());
+  E->setLocation(ReadSourceLocation());
+  E->setElidable(Record.readInt());
+  E->setHadMultipleCandidates(Record.readInt());
+  E->setListInitialization(Record.readInt());
+  E->setStdInitListInitialization(Record.readInt());
+  E->setRequiresZeroInitialization(Record.readInt());
+  E->setConstructionKind((CXXConstructExpr::ConstructionKind)Record.readInt());
+  E->ParenOrBraceRange = ReadSourceRange();
 }
 
 void ASTStmtReader::VisitCXXInheritedCtorInitExpr(CXXInheritedCtorInitExpr *E) {
   VisitExpr(E);
-  E->Constructor = ReadDeclAs<CXXConstructorDecl>(Record, Idx);
-  E->Loc = ReadSourceLocation(Record, Idx);
-  E->ConstructsVirtualBase = Record[Idx++];
-  E->InheritedFromVirtualBase = Record[Idx++];
+  E->Constructor = ReadDeclAs<CXXConstructorDecl>();
+  E->Loc = ReadSourceLocation();
+  E->ConstructsVirtualBase = Record.readInt();
+  E->InheritedFromVirtualBase = Record.readInt();
 }
 
 void ASTStmtReader::VisitCXXTemporaryObjectExpr(CXXTemporaryObjectExpr *E) {
   VisitCXXConstructExpr(E);
-  E->Type = GetTypeSourceInfo(Record, Idx);
+  E->Type = GetTypeSourceInfo();
 }
 
 void ASTStmtReader::VisitLambdaExpr(LambdaExpr *E) {
   VisitExpr(E);
-  unsigned NumCaptures = Record[Idx++];
+  unsigned NumCaptures = Record.readInt();
   assert(NumCaptures == E->NumCaptures);(void)NumCaptures;
-  unsigned NumArrayIndexVars = Record[Idx++];
-  E->IntroducerRange = ReadSourceRange(Record, Idx);
-  E->CaptureDefault = static_cast<LambdaCaptureDefault>(Record[Idx++]);
-  E->CaptureDefaultLoc = ReadSourceLocation(Record, Idx);
-  E->ExplicitParams = Record[Idx++];
-  E->ExplicitResultType = Record[Idx++];
-  E->ClosingBrace = ReadSourceLocation(Record, Idx);
-  
+  E->IntroducerRange = ReadSourceRange();
+  E->CaptureDefault = static_cast<LambdaCaptureDefault>(Record.readInt());
+  E->CaptureDefaultLoc = ReadSourceLocation();
+  E->ExplicitParams = Record.readInt();
+  E->ExplicitResultType = Record.readInt();
+  E->ClosingBrace = ReadSourceLocation();
+
   // Read capture initializers.
   for (LambdaExpr::capture_init_iterator C = E->capture_init_begin(),
                                       CEnd = E->capture_init_end();
        C != CEnd; ++C)
-    *C = Reader.ReadSubExpr();
-  
-  // Read array capture index variables.
-  if (NumArrayIndexVars > 0) {
-    unsigned *ArrayIndexStarts = E->getArrayIndexStarts();
-    for (unsigned I = 0; I != NumCaptures + 1; ++I)
-      ArrayIndexStarts[I] = Record[Idx++];
-    
-    VarDecl **ArrayIndexVars = E->getArrayIndexVars();
-    for (unsigned I = 0; I != NumArrayIndexVars; ++I)
-      ArrayIndexVars[I] = ReadDeclAs<VarDecl>(Record, Idx);
-  }
+    *C = Record.readSubExpr();
 }
 
 void
 ASTStmtReader::VisitCXXStdInitializerListExpr(CXXStdInitializerListExpr *E) {
   VisitExpr(E);
-  E->SubExpr = Reader.ReadSubExpr();
+  E->SubExpr = Record.readSubExpr();
 }
 
 void ASTStmtReader::VisitCXXNamedCastExpr(CXXNamedCastExpr *E) {
   VisitExplicitCastExpr(E);
-  SourceRange R = ReadSourceRange(Record, Idx);
+  SourceRange R = ReadSourceRange();
   E->Loc = R.getBegin();
   E->RParenLoc = R.getEnd();
-  R = ReadSourceRange(Record, Idx);
+  R = ReadSourceRange();
   E->AngleBrackets = R;
 }
 
@@ -1336,342 +1305,345 @@ void ASTStmtReader::VisitCXXConstCastExpr(CXXConstCastExpr *E) {
 
 void ASTStmtReader::VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr *E) {
   VisitExplicitCastExpr(E);
-  E->setLParenLoc(ReadSourceLocation(Record, Idx));
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
+  E->setLParenLoc(ReadSourceLocation());
+  E->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitUserDefinedLiteral(UserDefinedLiteral *E) {
   VisitCallExpr(E);
-  E->UDSuffixLoc = ReadSourceLocation(Record, Idx);
+  E->UDSuffixLoc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr *E) {
   VisitExpr(E);
-  E->setValue(Record[Idx++]);
-  E->setLocation(ReadSourceLocation(Record, Idx));
+  E->setValue(Record.readInt());
+  E->setLocation(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitCXXNullPtrLiteralExpr(CXXNullPtrLiteralExpr *E) {
   VisitExpr(E);
-  E->setLocation(ReadSourceLocation(Record, Idx));
+  E->setLocation(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitCXXTypeidExpr(CXXTypeidExpr *E) {
   VisitExpr(E);
-  E->setSourceRange(ReadSourceRange(Record, Idx));
+  E->setSourceRange(ReadSourceRange());
   if (E->isTypeOperand()) { // typeid(int)
     E->setTypeOperandSourceInfo(
-        GetTypeSourceInfo(Record, Idx));
+        GetTypeSourceInfo());
     return;
   }
-  
+
   // typeid(42+2)
-  E->setExprOperand(Reader.ReadSubExpr());
+  E->setExprOperand(Record.readSubExpr());
 }
 
 void ASTStmtReader::VisitCXXThisExpr(CXXThisExpr *E) {
   VisitExpr(E);
-  E->setLocation(ReadSourceLocation(Record, Idx));
-  E->setImplicit(Record[Idx++]);
+  E->setLocation(ReadSourceLocation());
+  E->setImplicit(Record.readInt());
 }
 
 void ASTStmtReader::VisitCXXThrowExpr(CXXThrowExpr *E) {
   VisitExpr(E);
-  E->ThrowLoc = ReadSourceLocation(Record, Idx);
-  E->Op = Reader.ReadSubExpr();
-  E->IsThrownVariableInScope = Record[Idx++];
+  E->ThrowLoc = ReadSourceLocation();
+  E->Op = Record.readSubExpr();
+  E->IsThrownVariableInScope = Record.readInt();
 }
 
 void ASTStmtReader::VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
   VisitExpr(E);
-  E->Param = ReadDeclAs<ParmVarDecl>(Record, Idx);
-  E->Loc = ReadSourceLocation(Record, Idx);
+  E->Param = ReadDeclAs<ParmVarDecl>();
+  E->Loc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitCXXDefaultInitExpr(CXXDefaultInitExpr *E) {
   VisitExpr(E);
-  E->Field = ReadDeclAs<FieldDecl>(Record, Idx);
-  E->Loc = ReadSourceLocation(Record, Idx);
+  E->Field = ReadDeclAs<FieldDecl>();
+  E->Loc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) {
   VisitExpr(E);
-  E->setTemporary(Reader.ReadCXXTemporary(F, Record, Idx));
-  E->setSubExpr(Reader.ReadSubExpr());
+  E->setTemporary(Record.readCXXTemporary());
+  E->setSubExpr(Record.readSubExpr());
 }
 
 void ASTStmtReader::VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E) {
   VisitExpr(E);
-  E->TypeInfo = GetTypeSourceInfo(Record, Idx);
-  E->RParenLoc = ReadSourceLocation(Record, Idx);
+  E->TypeInfo = GetTypeSourceInfo();
+  E->RParenLoc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitCXXNewExpr(CXXNewExpr *E) {
   VisitExpr(E);
-  E->GlobalNew = Record[Idx++];
-  bool isArray = Record[Idx++];
-  E->UsualArrayDeleteWantsSize = Record[Idx++];
-  unsigned NumPlacementArgs = Record[Idx++];
-  E->StoredInitializationStyle = Record[Idx++];
-  E->setOperatorNew(ReadDeclAs<FunctionDecl>(Record, Idx));
-  E->setOperatorDelete(ReadDeclAs<FunctionDecl>(Record, Idx));
-  E->AllocatedTypeInfo = GetTypeSourceInfo(Record, Idx);
-  E->TypeIdParens = ReadSourceRange(Record, Idx);
-  E->Range = ReadSourceRange(Record, Idx);
-  E->DirectInitRange = ReadSourceRange(Record, Idx);
-
-  E->AllocateArgsArray(Reader.getContext(), isArray, NumPlacementArgs,
+  E->GlobalNew = Record.readInt();
+  bool isArray = Record.readInt();
+  E->PassAlignment = Record.readInt();
+  E->UsualArrayDeleteWantsSize = Record.readInt();
+  unsigned NumPlacementArgs = Record.readInt();
+  E->StoredInitializationStyle = Record.readInt();
+  E->setOperatorNew(ReadDeclAs<FunctionDecl>());
+  E->setOperatorDelete(ReadDeclAs<FunctionDecl>());
+  E->AllocatedTypeInfo = GetTypeSourceInfo();
+  E->TypeIdParens = ReadSourceRange();
+  E->Range = ReadSourceRange();
+  E->DirectInitRange = ReadSourceRange();
+
+  E->AllocateArgsArray(Record.getContext(), isArray, NumPlacementArgs,
                        E->StoredInitializationStyle != 0);
 
   // Install all the subexpressions.
   for (CXXNewExpr::raw_arg_iterator I = E->raw_arg_begin(),e = E->raw_arg_end();
        I != e; ++I)
-    *I = Reader.ReadSubStmt();
+    *I = Record.readSubStmt();
 }
 
 void ASTStmtReader::VisitCXXDeleteExpr(CXXDeleteExpr *E) {
   VisitExpr(E);
-  E->GlobalDelete = Record[Idx++];
-  E->ArrayForm = Record[Idx++];
-  E->ArrayFormAsWritten = Record[Idx++];
-  E->UsualArrayDeleteWantsSize = Record[Idx++];
-  E->OperatorDelete = ReadDeclAs<FunctionDecl>(Record, Idx);
-  E->Argument = Reader.ReadSubExpr();
-  E->Loc = ReadSourceLocation(Record, Idx);
+  E->GlobalDelete = Record.readInt();
+  E->ArrayForm = Record.readInt();
+  E->ArrayFormAsWritten = Record.readInt();
+  E->UsualArrayDeleteWantsSize = Record.readInt();
+  E->OperatorDelete = ReadDeclAs<FunctionDecl>();
+  E->Argument = Record.readSubExpr();
+  E->Loc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitCXXPseudoDestructorExpr(CXXPseudoDestructorExpr *E) {
   VisitExpr(E);
 
-  E->Base = Reader.ReadSubExpr();
-  E->IsArrow = Record[Idx++];
-  E->OperatorLoc = ReadSourceLocation(Record, Idx);
-  E->QualifierLoc = Reader.ReadNestedNameSpecifierLoc(F, Record, Idx);
-  E->ScopeType = GetTypeSourceInfo(Record, Idx);
-  E->ColonColonLoc = ReadSourceLocation(Record, Idx);
-  E->TildeLoc = ReadSourceLocation(Record, Idx);
-  
-  IdentifierInfo *II = Reader.GetIdentifierInfo(F, Record, Idx);
+  E->Base = Record.readSubExpr();
+  E->IsArrow = Record.readInt();
+  E->OperatorLoc = ReadSourceLocation();
+  E->QualifierLoc = Record.readNestedNameSpecifierLoc();
+  E->ScopeType = GetTypeSourceInfo();
+  E->ColonColonLoc = ReadSourceLocation();
+  E->TildeLoc = ReadSourceLocation();
+
+  IdentifierInfo *II = Record.getIdentifierInfo();
   if (II)
-    E->setDestroyedType(II, ReadSourceLocation(Record, Idx));
+    E->setDestroyedType(II, ReadSourceLocation());
   else
-    E->setDestroyedType(GetTypeSourceInfo(Record, Idx));
+    E->setDestroyedType(GetTypeSourceInfo());
 }
 
 void ASTStmtReader::VisitExprWithCleanups(ExprWithCleanups *E) {
   VisitExpr(E);
 
-  unsigned NumObjects = Record[Idx++];
+  unsigned NumObjects = Record.readInt();
   assert(NumObjects == E->getNumObjects());
   for (unsigned i = 0; i != NumObjects; ++i)
     E->getTrailingObjects<BlockDecl *>()[i] =
-        ReadDeclAs<BlockDecl>(Record, Idx);
+        ReadDeclAs<BlockDecl>();
 
-  E->ExprWithCleanupsBits.CleanupsHaveSideEffects = Record[Idx++];
-  E->SubExpr = Reader.ReadSubExpr();
+  E->ExprWithCleanupsBits.CleanupsHaveSideEffects = Record.readInt();
+  E->SubExpr = Record.readSubExpr();
 }
 
 void
 ASTStmtReader::VisitCXXDependentScopeMemberExpr(CXXDependentScopeMemberExpr *E){
   VisitExpr(E);
 
-  if (Record[Idx++]) // HasTemplateKWAndArgsInfo
+  if (Record.readInt()) // HasTemplateKWAndArgsInfo
     ReadTemplateKWAndArgsInfo(
         *E->getTrailingObjects<ASTTemplateKWAndArgsInfo>(),
         E->getTrailingObjects<TemplateArgumentLoc>(),
-        /*NumTemplateArgs=*/Record[Idx++]);
+        /*NumTemplateArgs=*/Record.readInt());
 
-  E->Base = Reader.ReadSubExpr();
-  E->BaseType = Reader.readType(F, Record, Idx);
-  E->IsArrow = Record[Idx++];
-  E->OperatorLoc = ReadSourceLocation(Record, Idx);
-  E->QualifierLoc = Reader.ReadNestedNameSpecifierLoc(F, Record, Idx);
-  E->FirstQualifierFoundInScope = ReadDeclAs<NamedDecl>(Record, Idx);
-  ReadDeclarationNameInfo(E->MemberNameInfo, Record, Idx);
+  E->Base = Record.readSubExpr();
+  E->BaseType = Record.readType();
+  E->IsArrow = Record.readInt();
+  E->OperatorLoc = ReadSourceLocation();
+  E->QualifierLoc = Record.readNestedNameSpecifierLoc();
+  E->FirstQualifierFoundInScope = ReadDeclAs<NamedDecl>();
+  ReadDeclarationNameInfo(E->MemberNameInfo);
 }
 
 void
 ASTStmtReader::VisitDependentScopeDeclRefExpr(DependentScopeDeclRefExpr *E) {
   VisitExpr(E);
 
-  if (Record[Idx++]) // HasTemplateKWAndArgsInfo
+  if (Record.readInt()) // HasTemplateKWAndArgsInfo
     ReadTemplateKWAndArgsInfo(
         *E->getTrailingObjects<ASTTemplateKWAndArgsInfo>(),
         E->getTrailingObjects<TemplateArgumentLoc>(),
-        /*NumTemplateArgs=*/Record[Idx++]);
+        /*NumTemplateArgs=*/Record.readInt());
 
-  E->QualifierLoc = Reader.ReadNestedNameSpecifierLoc(F, Record, Idx);
-  ReadDeclarationNameInfo(E->NameInfo, Record, Idx);
+  E->QualifierLoc = Record.readNestedNameSpecifierLoc();
+  ReadDeclarationNameInfo(E->NameInfo);
 }
 
 void
 ASTStmtReader::VisitCXXUnresolvedConstructExpr(CXXUnresolvedConstructExpr *E) {
   VisitExpr(E);
-  assert(Record[Idx] == E->arg_size() && "Read wrong record during creation ?");
-  ++Idx; // NumArgs;
+  assert(Record.peekInt() == E->arg_size() &&
+         "Read wrong record during creation ?");
+  Record.skipInts(1);
   for (unsigned I = 0, N = E->arg_size(); I != N; ++I)
-    E->setArg(I, Reader.ReadSubExpr());
-  E->Type = GetTypeSourceInfo(Record, Idx);
-  E->setLParenLoc(ReadSourceLocation(Record, Idx));
-  E->setRParenLoc(ReadSourceLocation(Record, Idx));
+    E->setArg(I, Record.readSubExpr());
+  E->Type = GetTypeSourceInfo();
+  E->setLParenLoc(ReadSourceLocation());
+  E->setRParenLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitOverloadExpr(OverloadExpr *E) {
   VisitExpr(E);
 
-  if (Record[Idx++]) // HasTemplateKWAndArgsInfo
+  if (Record.readInt()) // HasTemplateKWAndArgsInfo
     ReadTemplateKWAndArgsInfo(*E->getTrailingASTTemplateKWAndArgsInfo(),
                               E->getTrailingTemplateArgumentLoc(),
-                              /*NumTemplateArgs=*/Record[Idx++]);
+                              /*NumTemplateArgs=*/Record.readInt());
 
-  unsigned NumDecls = Record[Idx++];
+  unsigned NumDecls = Record.readInt();
   UnresolvedSet<8> Decls;
   for (unsigned i = 0; i != NumDecls; ++i) {
-    NamedDecl *D = ReadDeclAs<NamedDecl>(Record, Idx);
-    AccessSpecifier AS = (AccessSpecifier)Record[Idx++];
+    NamedDecl *D = ReadDeclAs<NamedDecl>();
+    AccessSpecifier AS = (AccessSpecifier)Record.readInt();
     Decls.addDecl(D, AS);
   }
-  E->initializeResults(Reader.getContext(), Decls.begin(), Decls.end());
+  E->initializeResults(Record.getContext(), Decls.begin(), Decls.end());
 
-  ReadDeclarationNameInfo(E->NameInfo, Record, Idx);
-  E->QualifierLoc = Reader.ReadNestedNameSpecifierLoc(F, Record, Idx);
+  ReadDeclarationNameInfo(E->NameInfo);
+  E->QualifierLoc = Record.readNestedNameSpecifierLoc();
 }
 
 void ASTStmtReader::VisitUnresolvedMemberExpr(UnresolvedMemberExpr *E) {
   VisitOverloadExpr(E);
-  E->IsArrow = Record[Idx++];
-  E->HasUnresolvedUsing = Record[Idx++];
-  E->Base = Reader.ReadSubExpr();
-  E->BaseType = Reader.readType(F, Record, Idx);
-  E->OperatorLoc = ReadSourceLocation(Record, Idx);
+  E->IsArrow = Record.readInt();
+  E->HasUnresolvedUsing = Record.readInt();
+  E->Base = Record.readSubExpr();
+  E->BaseType = Record.readType();
+  E->OperatorLoc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitUnresolvedLookupExpr(UnresolvedLookupExpr *E) {
   VisitOverloadExpr(E);
-  E->RequiresADL = Record[Idx++];
-  E->Overloaded = Record[Idx++];
-  E->NamingClass = ReadDeclAs<CXXRecordDecl>(Record, Idx);
+  E->RequiresADL = Record.readInt();
+  E->Overloaded = Record.readInt();
+  E->NamingClass = ReadDeclAs<CXXRecordDecl>();
 }
 
 void ASTStmtReader::VisitTypeTraitExpr(TypeTraitExpr *E) {
   VisitExpr(E);
-  E->TypeTraitExprBits.NumArgs = Record[Idx++];
-  E->TypeTraitExprBits.Kind = Record[Idx++];
-  E->TypeTraitExprBits.Value = Record[Idx++];
-  SourceRange Range = ReadSourceRange(Record, Idx);
+  E->TypeTraitExprBits.NumArgs = Record.readInt();
+  E->TypeTraitExprBits.Kind = Record.readInt();
+  E->TypeTraitExprBits.Value = Record.readInt();
+  SourceRange Range = ReadSourceRange();
   E->Loc = Range.getBegin();
   E->RParenLoc = Range.getEnd();
 
   TypeSourceInfo **Args = E->getTrailingObjects<TypeSourceInfo *>();
   for (unsigned I = 0, N = E->getNumArgs(); I != N; ++I)
-    Args[I] = GetTypeSourceInfo(Record, Idx);
+    Args[I] = GetTypeSourceInfo();
 }
 
 void ASTStmtReader::VisitArrayTypeTraitExpr(ArrayTypeTraitExpr *E) {
   VisitExpr(E);
-  E->ATT = (ArrayTypeTrait)Record[Idx++];
-  E->Value = (unsigned int)Record[Idx++];
-  SourceRange Range = ReadSourceRange(Record, Idx);
+  E->ATT = (ArrayTypeTrait)Record.readInt();
+  E->Value = (unsigned int)Record.readInt();
+  SourceRange Range = ReadSourceRange();
   E->Loc = Range.getBegin();
   E->RParen = Range.getEnd();
-  E->QueriedType = GetTypeSourceInfo(Record, Idx);
+  E->QueriedType = GetTypeSourceInfo();
+  E->Dimension = Record.readSubExpr();
 }
 
 void ASTStmtReader::VisitExpressionTraitExpr(ExpressionTraitExpr *E) {
   VisitExpr(E);
-  E->ET = (ExpressionTrait)Record[Idx++];
-  E->Value = (bool)Record[Idx++];
-  SourceRange Range = ReadSourceRange(Record, Idx);
-  E->QueriedExpression = Reader.ReadSubExpr();
+  E->ET = (ExpressionTrait)Record.readInt();
+  E->Value = (bool)Record.readInt();
+  SourceRange Range = ReadSourceRange();
+  E->QueriedExpression = Record.readSubExpr();
   E->Loc = Range.getBegin();
   E->RParen = Range.getEnd();
 }
 
 void ASTStmtReader::VisitCXXNoexceptExpr(CXXNoexceptExpr *E) {
   VisitExpr(E);
-  E->Value = (bool)Record[Idx++];
-  E->Range = ReadSourceRange(Record, Idx);
-  E->Operand = Reader.ReadSubExpr();
+  E->Value = (bool)Record.readInt();
+  E->Range = ReadSourceRange();
+  E->Operand = Record.readSubExpr();
 }
 
 void ASTStmtReader::VisitPackExpansionExpr(PackExpansionExpr *E) {
   VisitExpr(E);
-  E->EllipsisLoc = ReadSourceLocation(Record, Idx);
-  E->NumExpansions = Record[Idx++];
-  E->Pattern = Reader.ReadSubExpr();  
+  E->EllipsisLoc = ReadSourceLocation();
+  E->NumExpansions = Record.readInt();
+  E->Pattern = Record.readSubExpr();
 }
 
 void ASTStmtReader::VisitSizeOfPackExpr(SizeOfPackExpr *E) {
   VisitExpr(E);
-  unsigned NumPartialArgs = Record[Idx++];
-  E->OperatorLoc = ReadSourceLocation(Record, Idx);
-  E->PackLoc = ReadSourceLocation(Record, Idx);
-  E->RParenLoc = ReadSourceLocation(Record, Idx);
-  E->Pack = Reader.ReadDeclAs<NamedDecl>(F, Record, Idx);
+  unsigned NumPartialArgs = Record.readInt();
+  E->OperatorLoc = ReadSourceLocation();
+  E->PackLoc = ReadSourceLocation();
+  E->RParenLoc = ReadSourceLocation();
+  E->Pack = Record.readDeclAs<NamedDecl>();
   if (E->isPartiallySubstituted()) {
     assert(E->Length == NumPartialArgs);
     for (auto *I = E->getTrailingObjects<TemplateArgument>(),
               *E = I + NumPartialArgs;
          I != E; ++I)
-      new (I) TemplateArgument(Reader.ReadTemplateArgument(F, Record, Idx));
+      new (I) TemplateArgument(Record.readTemplateArgument());
   } else if (!E->isValueDependent()) {
-    E->Length = Record[Idx++];
+    E->Length = Record.readInt();
   }
 }
 
 void ASTStmtReader::VisitSubstNonTypeTemplateParmExpr(
                                               SubstNonTypeTemplateParmExpr *E) {
   VisitExpr(E);
-  E->Param = ReadDeclAs<NonTypeTemplateParmDecl>(Record, Idx);
-  E->NameLoc = ReadSourceLocation(Record, Idx);
-  E->Replacement = Reader.ReadSubExpr();
+  E->Param = ReadDeclAs<NonTypeTemplateParmDecl>();
+  E->NameLoc = ReadSourceLocation();
+  E->Replacement = Record.readSubExpr();
 }
 
 void ASTStmtReader::VisitSubstNonTypeTemplateParmPackExpr(
                                           SubstNonTypeTemplateParmPackExpr *E) {
   VisitExpr(E);
-  E->Param = ReadDeclAs<NonTypeTemplateParmDecl>(Record, Idx);
-  TemplateArgument ArgPack = Reader.ReadTemplateArgument(F, Record, Idx);
+  E->Param = ReadDeclAs<NonTypeTemplateParmDecl>();
+  TemplateArgument ArgPack = Record.readTemplateArgument();
   if (ArgPack.getKind() != TemplateArgument::Pack)
     return;
-  
+
   E->Arguments = ArgPack.pack_begin();
   E->NumArguments = ArgPack.pack_size();
-  E->NameLoc = ReadSourceLocation(Record, Idx);
+  E->NameLoc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitFunctionParmPackExpr(FunctionParmPackExpr *E) {
   VisitExpr(E);
-  E->NumParameters = Record[Idx++];
-  E->ParamPack = ReadDeclAs<ParmVarDecl>(Record, Idx);
-  E->NameLoc = ReadSourceLocation(Record, Idx);
+  E->NumParameters = Record.readInt();
+  E->ParamPack = ReadDeclAs<ParmVarDecl>();
+  E->NameLoc = ReadSourceLocation();
   ParmVarDecl **Parms = E->getTrailingObjects<ParmVarDecl *>();
   for (unsigned i = 0, n = E->NumParameters; i != n; ++i)
-    Parms[i] = ReadDeclAs<ParmVarDecl>(Record, Idx);
+    Parms[i] = ReadDeclAs<ParmVarDecl>();
 }
 
 void ASTStmtReader::VisitMaterializeTemporaryExpr(MaterializeTemporaryExpr *E) {
   VisitExpr(E);
-  E->State = Reader.ReadSubExpr();
-  auto VD = ReadDeclAs<ValueDecl>(Record, Idx);
-  unsigned ManglingNumber = Record[Idx++];
+  E->State = Record.readSubExpr();
+  auto VD = ReadDeclAs<ValueDecl>();
+  unsigned ManglingNumber = Record.readInt();
   E->setExtendingDecl(VD, ManglingNumber);
 }
 
 void ASTStmtReader::VisitCXXFoldExpr(CXXFoldExpr *E) {
   VisitExpr(E);
-  E->LParenLoc = ReadSourceLocation(Record, Idx);
-  E->EllipsisLoc = ReadSourceLocation(Record, Idx);
-  E->RParenLoc = ReadSourceLocation(Record, Idx);
-  E->SubExprs[0] = Reader.ReadSubExpr();
-  E->SubExprs[1] = Reader.ReadSubExpr();
-  E->Opcode = (BinaryOperatorKind)Record[Idx++];
+  E->LParenLoc = ReadSourceLocation();
+  E->EllipsisLoc = ReadSourceLocation();
+  E->RParenLoc = ReadSourceLocation();
+  E->SubExprs[0] = Record.readSubExpr();
+  E->SubExprs[1] = Record.readSubExpr();
+  E->Opcode = (BinaryOperatorKind)Record.readInt();
 }
 
 void ASTStmtReader::VisitOpaqueValueExpr(OpaqueValueExpr *E) {
   VisitExpr(E);
-  E->SourceExpr = Reader.ReadSubExpr();
-  E->Loc = ReadSourceLocation(Record, Idx);
+  E->SourceExpr = Record.readSubExpr();
+  E->Loc = ReadSourceLocation();
 }
 
 void ASTStmtReader::VisitTypoExpr(TypoExpr *E) {
@@ -1683,59 +1655,59 @@ void ASTStmtReader::VisitTypoExpr(TypoExpr *E) {
 //===----------------------------------------------------------------------===//
 void ASTStmtReader::VisitMSPropertyRefExpr(MSPropertyRefExpr *E) {
   VisitExpr(E);
-  E->IsArrow = (Record[Idx++] != 0);
-  E->BaseExpr = Reader.ReadSubExpr();
-  E->QualifierLoc = Reader.ReadNestedNameSpecifierLoc(F, Record, Idx);
-  E->MemberLoc = ReadSourceLocation(Record, Idx);
-  E->TheDecl = ReadDeclAs<MSPropertyDecl>(Record, Idx);
+  E->IsArrow = (Record.readInt() != 0);
+  E->BaseExpr = Record.readSubExpr();
+  E->QualifierLoc = Record.readNestedNameSpecifierLoc();
+  E->MemberLoc = ReadSourceLocation();
+  E->TheDecl = ReadDeclAs<MSPropertyDecl>();
 }
 
 void ASTStmtReader::VisitMSPropertySubscriptExpr(MSPropertySubscriptExpr *E) {
   VisitExpr(E);
-  E->setBase(Reader.ReadSubExpr());
-  E->setIdx(Reader.ReadSubExpr());
-  E->setRBracketLoc(ReadSourceLocation(Record, Idx));
+  E->setBase(Record.readSubExpr());
+  E->setIdx(Record.readSubExpr());
+  E->setRBracketLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitCXXUuidofExpr(CXXUuidofExpr *E) {
   VisitExpr(E);
-  E->setSourceRange(ReadSourceRange(Record, Idx));
-  std::string UuidStr = ReadString(Record, Idx);
-  E->setUuidStr(StringRef(UuidStr).copy(Reader.getContext()));
+  E->setSourceRange(ReadSourceRange());
+  std::string UuidStr = ReadString();
+  E->setUuidStr(StringRef(UuidStr).copy(Record.getContext()));
   if (E->isTypeOperand()) { // __uuidof(ComType)
     E->setTypeOperandSourceInfo(
-        GetTypeSourceInfo(Record, Idx));
+        GetTypeSourceInfo());
     return;
   }
-  
+
   // __uuidof(expr)
-  E->setExprOperand(Reader.ReadSubExpr());
+  E->setExprOperand(Record.readSubExpr());
 }
 
 void ASTStmtReader::VisitSEHLeaveStmt(SEHLeaveStmt *S) {
   VisitStmt(S);
-  S->setLeaveLoc(ReadSourceLocation(Record, Idx));
+  S->setLeaveLoc(ReadSourceLocation());
 }
 
 void ASTStmtReader::VisitSEHExceptStmt(SEHExceptStmt *S) {
   VisitStmt(S);
-  S->Loc = ReadSourceLocation(Record, Idx);
-  S->Children[SEHExceptStmt::FILTER_EXPR] = Reader.ReadSubStmt();
-  S->Children[SEHExceptStmt::BLOCK] = Reader.ReadSubStmt();
+  S->Loc = ReadSourceLocation();
+  S->Children[SEHExceptStmt::FILTER_EXPR] = Record.readSubStmt();
+  S->Children[SEHExceptStmt::BLOCK] = Record.readSubStmt();
 }
 
 void ASTStmtReader::VisitSEHFinallyStmt(SEHFinallyStmt *S) {
   VisitStmt(S);
-  S->Loc = ReadSourceLocation(Record, Idx);
-  S->Block = Reader.ReadSubStmt();
+  S->Loc = ReadSourceLocation();
+  S->Block = Record.readSubStmt();
 }
 
 void ASTStmtReader::VisitSEHTryStmt(SEHTryStmt *S) {
   VisitStmt(S);
-  S->IsCXXTry = Record[Idx++];
-  S->TryLoc = ReadSourceLocation(Record, Idx);
-  S->Children[SEHTryStmt::TRY] = Reader.ReadSubStmt();
-  S->Children[SEHTryStmt::HANDLER] = Reader.ReadSubStmt();
+  S->IsCXXTry = Record.readInt();
+  S->TryLoc = ReadSourceLocation();
+  S->Children[SEHTryStmt::TRY] = Record.readSubStmt();
+  S->Children[SEHTryStmt::HANDLER] = Record.readSubStmt();
 }
 
 //===----------------------------------------------------------------------===//
@@ -1744,7 +1716,7 @@ void ASTStmtReader::VisitSEHTryStmt(SEHTryStmt *S) {
 
 void ASTStmtReader::VisitCUDAKernelCallExpr(CUDAKernelCallExpr *E) {
   VisitCallExpr(E);
-  E->setConfig(cast<CallExpr>(Reader.ReadSubExpr()));
+  E->setConfig(cast<CallExpr>(Record.readSubExpr()));
 }
 
 //===----------------------------------------------------------------------===//
@@ -1752,9 +1724,9 @@ void ASTStmtReader::VisitCUDAKernelCallExpr(CUDAKernelCallExpr *E) {
 //===----------------------------------------------------------------------===//
 void ASTStmtReader::VisitAsTypeExpr(AsTypeExpr *E) {
   VisitExpr(E);
-  E->BuiltinLoc = ReadSourceLocation(Record, Idx);
-  E->RParenLoc = ReadSourceLocation(Record, Idx);
-  E->SrcExpr = Reader.ReadSubExpr();
+  E->BuiltinLoc = ReadSourceLocation();
+  E->RParenLoc = ReadSourceLocation();
+  E->SrcExpr = Record.readSubExpr();
 }
 
 //===----------------------------------------------------------------------===//
@@ -1765,12 +1737,9 @@ namespace clang {
 class OMPClauseReader : public OMPClauseVisitor<OMPClauseReader> {
   ASTStmtReader *Reader;
   ASTContext &Context;
-  const ASTReader::RecordData &Record;
-  unsigned &Idx;
 public:
-  OMPClauseReader(ASTStmtReader *R, ASTContext &C,
-                  const ASTReader::RecordData &Record, unsigned &Idx)
-    : Reader(R), Context(C), Record(Record), Idx(Idx) { }
+  OMPClauseReader(ASTStmtReader *R, ASTRecordReader &Record)
+      : Reader(R), Context(Record.getContext()) {}
 #define OPENMP_CLAUSE(Name, Class) void Visit##Class(Class *C);
 #include "clang/Basic/OpenMPKinds.def"
   OMPClause *readClause();
@@ -1781,7 +1750,7 @@ public:
 
 OMPClause *OMPClauseReader::readClause() {
   OMPClause *C;
-  switch (Record[Idx++]) {
+  switch (Reader->Record.readInt()) {
   case OMPC_if:
     C = new (Context) OMPIfClause();
     break;
@@ -1846,46 +1815,46 @@ OMPClause *OMPClauseReader::readClause() {
     C = new (Context) OMPNogroupClause();
     break;
   case OMPC_private:
-    C = OMPPrivateClause::CreateEmpty(Context, Record[Idx++]);
+    C = OMPPrivateClause::CreateEmpty(Context, Reader->Record.readInt());
     break;
   case OMPC_firstprivate:
-    C = OMPFirstprivateClause::CreateEmpty(Context, Record[Idx++]);
+    C = OMPFirstprivateClause::CreateEmpty(Context, Reader->Record.readInt());
     break;
   case OMPC_lastprivate:
-    C = OMPLastprivateClause::CreateEmpty(Context, Record[Idx++]);
+    C = OMPLastprivateClause::CreateEmpty(Context, Reader->Record.readInt());
     break;
   case OMPC_shared:
-    C = OMPSharedClause::CreateEmpty(Context, Record[Idx++]);
+    C = OMPSharedClause::CreateEmpty(Context, Reader->Record.readInt());
     break;
   case OMPC_reduction:
-    C = OMPReductionClause::CreateEmpty(Context, Record[Idx++]);
+    C = OMPReductionClause::CreateEmpty(Context, Reader->Record.readInt());
     break;
   case OMPC_linear:
-    C = OMPLinearClause::CreateEmpty(Context, Record[Idx++]);
+    C = OMPLinearClause::CreateEmpty(Context, Reader->Record.readInt());
     break;
   case OMPC_aligned:
-    C = OMPAlignedClause::CreateEmpty(Context, Record[Idx++]);
+    C = OMPAlignedClause::CreateEmpty(Context, Reader->Record.readInt());
     break;
   case OMPC_copyin:
-    C = OMPCopyinClause::CreateEmpty(Context, Record[Idx++]);
+    C = OMPCopyinClause::CreateEmpty(Context, Reader->Record.readInt());
     break;
   case OMPC_copyprivate:
-    C = OMPCopyprivateClause::CreateEmpty(Context, Record[Idx++]);
+    C = OMPCopyprivateClause::CreateEmpty(Context, Reader->Record.readInt());
     break;
   case OMPC_flush:
-    C = OMPFlushClause::CreateEmpty(Context, Record[Idx++]);
+    C = OMPFlushClause::CreateEmpty(Context, Reader->Record.readInt());
     break;
   case OMPC_depend:
-    C = OMPDependClause::CreateEmpty(Context, Record[Idx++]);
+    C = OMPDependClause::CreateEmpty(Context, Reader->Record.readInt());
     break;
   case OMPC_device:
     C = new (Context) OMPDeviceClause();
     break;
   case OMPC_map: {
-    unsigned NumVars = Record[Idx++];
-    unsigned NumDeclarations = Record[Idx++];
-    unsigned NumLists = Record[Idx++];
-    unsigned NumComponents = Record[Idx++];
+    unsigned NumVars = Reader->Record.readInt();
+    unsigned NumDeclarations = Reader->Record.readInt();
+    unsigned NumLists = Reader->Record.readInt();
+    unsigned NumComponents = Reader->Record.readInt();
     C = OMPMapClause::CreateEmpty(Context, NumVars, NumDeclarations, NumLists,
                                   NumComponents);
     break;
@@ -1915,112 +1884,124 @@ OMPClause *OMPClauseReader::readClause() {
     C = new (Context) OMPDefaultmapClause();
     break;
   case OMPC_to: {
-    unsigned NumVars = Record[Idx++];
-    unsigned NumDeclarations = Record[Idx++];
-    unsigned NumLists = Record[Idx++];
-    unsigned NumComponents = Record[Idx++];
+    unsigned NumVars = Reader->Record.readInt();
+    unsigned NumDeclarations = Reader->Record.readInt();
+    unsigned NumLists = Reader->Record.readInt();
+    unsigned NumComponents = Reader->Record.readInt();
     C = OMPToClause::CreateEmpty(Context, NumVars, NumDeclarations, NumLists,
                                  NumComponents);
     break;
   }
   case OMPC_from: {
-    unsigned NumVars = Record[Idx++];
-    unsigned NumDeclarations = Record[Idx++];
-    unsigned NumLists = Record[Idx++];
-    unsigned NumComponents = Record[Idx++];
+    unsigned NumVars = Reader->Record.readInt();
+    unsigned NumDeclarations = Reader->Record.readInt();
+    unsigned NumLists = Reader->Record.readInt();
+    unsigned NumComponents = Reader->Record.readInt();
     C = OMPFromClause::CreateEmpty(Context, NumVars, NumDeclarations, NumLists,
                                    NumComponents);
     break;
   }
-  case OMPC_use_device_ptr:
-    C = OMPUseDevicePtrClause::CreateEmpty(Context, Record[Idx++]);
+  case OMPC_use_device_ptr: {
+    unsigned NumVars = Reader->Record.readInt();
+    unsigned NumDeclarations = Reader->Record.readInt();
+    unsigned NumLists = Reader->Record.readInt();
+    unsigned NumComponents = Reader->Record.readInt();
+    C = OMPUseDevicePtrClause::CreateEmpty(Context, NumVars, NumDeclarations,
+                                           NumLists, NumComponents);
     break;
-  case OMPC_is_device_ptr:
-    C = OMPIsDevicePtrClause::CreateEmpty(Context, Record[Idx++]);
+  }
+  case OMPC_is_device_ptr: {
+    unsigned NumVars = Reader->Record.readInt();
+    unsigned NumDeclarations = Reader->Record.readInt();
+    unsigned NumLists = Reader->Record.readInt();
+    unsigned NumComponents = Reader->Record.readInt();
+    C = OMPIsDevicePtrClause::CreateEmpty(Context, NumVars, NumDeclarations,
+                                          NumLists, NumComponents);
     break;
   }
+  }
   Visit(C);
-  C->setLocStart(Reader->ReadSourceLocation(Record, Idx));
-  C->setLocEnd(Reader->ReadSourceLocation(Record, Idx));
+  C->setLocStart(Reader->ReadSourceLocation());
+  C->setLocEnd(Reader->ReadSourceLocation());
 
   return C;
 }
 
 void OMPClauseReader::VisitOMPClauseWithPreInit(OMPClauseWithPreInit *C) {
-  C->setPreInitStmt(Reader->Reader.ReadSubStmt());
+  C->setPreInitStmt(Reader->Record.readSubStmt());
 }
 
 void OMPClauseReader::VisitOMPClauseWithPostUpdate(OMPClauseWithPostUpdate *C) {
   VisitOMPClauseWithPreInit(C);
-  C->setPostUpdateExpr(Reader->Reader.ReadSubExpr());
+  C->setPostUpdateExpr(Reader->Record.readSubExpr());
 }
 
 void OMPClauseReader::VisitOMPIfClause(OMPIfClause *C) {
-  C->setNameModifier(static_cast<OpenMPDirectiveKind>(Record[Idx++]));
-  C->setNameModifierLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setColonLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setCondition(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setNameModifier(static_cast<OpenMPDirectiveKind>(Reader->Record.readInt()));
+  C->setNameModifierLoc(Reader->ReadSourceLocation());
+  C->setColonLoc(Reader->ReadSourceLocation());
+  C->setCondition(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPFinalClause(OMPFinalClause *C) {
-  C->setCondition(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setCondition(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPNumThreadsClause(OMPNumThreadsClause *C) {
-  C->setNumThreads(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setNumThreads(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPSafelenClause(OMPSafelenClause *C) {
-  C->setSafelen(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setSafelen(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPSimdlenClause(OMPSimdlenClause *C) {
-  C->setSimdlen(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setSimdlen(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPCollapseClause(OMPCollapseClause *C) {
-  C->setNumForLoops(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setNumForLoops(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPDefaultClause(OMPDefaultClause *C) {
   C->setDefaultKind(
-       static_cast<OpenMPDefaultClauseKind>(Record[Idx++]));
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setDefaultKindKwLoc(Reader->ReadSourceLocation(Record, Idx));
+       static_cast<OpenMPDefaultClauseKind>(Reader->Record.readInt()));
+  C->setLParenLoc(Reader->ReadSourceLocation());
+  C->setDefaultKindKwLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPProcBindClause(OMPProcBindClause *C) {
   C->setProcBindKind(
-       static_cast<OpenMPProcBindClauseKind>(Record[Idx++]));
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setProcBindKindKwLoc(Reader->ReadSourceLocation(Record, Idx));
+       static_cast<OpenMPProcBindClauseKind>(Reader->Record.readInt()));
+  C->setLParenLoc(Reader->ReadSourceLocation());
+  C->setProcBindKindKwLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPScheduleClause(OMPScheduleClause *C) {
   VisitOMPClauseWithPreInit(C);
   C->setScheduleKind(
-       static_cast<OpenMPScheduleClauseKind>(Record[Idx++]));
+       static_cast<OpenMPScheduleClauseKind>(Reader->Record.readInt()));
   C->setFirstScheduleModifier(
-      static_cast<OpenMPScheduleClauseModifier>(Record[Idx++]));
+      static_cast<OpenMPScheduleClauseModifier>(Reader->Record.readInt()));
   C->setSecondScheduleModifier(
-      static_cast<OpenMPScheduleClauseModifier>(Record[Idx++]));
-  C->setChunkSize(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setFirstScheduleModifierLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setSecondScheduleModifierLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setScheduleKindLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setCommaLoc(Reader->ReadSourceLocation(Record, Idx));
+      static_cast<OpenMPScheduleClauseModifier>(Reader->Record.readInt()));
+  C->setChunkSize(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
+  C->setFirstScheduleModifierLoc(Reader->ReadSourceLocation());
+  C->setSecondScheduleModifierLoc(Reader->ReadSourceLocation());
+  C->setScheduleKindLoc(Reader->ReadSourceLocation());
+  C->setCommaLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPOrderedClause(OMPOrderedClause *C) {
-  C->setNumForLoops(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setNumForLoops(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPNowaitClause(OMPNowaitClause *) {}
@@ -2046,83 +2027,82 @@ void OMPClauseReader::VisitOMPSIMDClause(OMPSIMDClause *) {}
 void OMPClauseReader::VisitOMPNogroupClause(OMPNogroupClause *) {}
 
 void OMPClauseReader::VisitOMPPrivateClause(OMPPrivateClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
   unsigned NumVars = C->varlist_size();
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setPrivateCopies(Vars);
 }
 
 void OMPClauseReader::VisitOMPFirstprivateClause(OMPFirstprivateClause *C) {
   VisitOMPClauseWithPreInit(C);
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
   unsigned NumVars = C->varlist_size();
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setPrivateCopies(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setInits(Vars);
 }
 
 void OMPClauseReader::VisitOMPLastprivateClause(OMPLastprivateClause *C) {
   VisitOMPClauseWithPostUpdate(C);
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
   unsigned NumVars = C->varlist_size();
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setPrivateCopies(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setSourceExprs(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setDestinationExprs(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setAssignmentOps(Vars);
 }
 
 void OMPClauseReader::VisitOMPSharedClause(OMPSharedClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
   unsigned NumVars = C->varlist_size();
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
 }
 
 void OMPClauseReader::VisitOMPReductionClause(OMPReductionClause *C) {
   VisitOMPClauseWithPostUpdate(C);
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setColonLoc(Reader->ReadSourceLocation(Record, Idx));
-  NestedNameSpecifierLoc NNSL =
-    Reader->Reader.ReadNestedNameSpecifierLoc(Reader->F, Record, Idx);
+  C->setLParenLoc(Reader->ReadSourceLocation());
+  C->setColonLoc(Reader->ReadSourceLocation());
+  NestedNameSpecifierLoc NNSL = Reader->Record.readNestedNameSpecifierLoc();
   DeclarationNameInfo DNI;
-  Reader->ReadDeclarationNameInfo(DNI, Record, Idx);
+  Reader->ReadDeclarationNameInfo(DNI);
   C->setQualifierLoc(NNSL);
   C->setNameInfo(DNI);
 
@@ -2130,151 +2110,152 @@ void OMPClauseReader::VisitOMPReductionClause(OMPReductionClause *C) {
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setPrivates(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setLHSExprs(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setRHSExprs(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setReductionOps(Vars);
 }
 
 void OMPClauseReader::VisitOMPLinearClause(OMPLinearClause *C) {
   VisitOMPClauseWithPostUpdate(C);
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setColonLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setModifier(static_cast<OpenMPLinearClauseKind>(Record[Idx++]));
-  C->setModifierLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
+  C->setColonLoc(Reader->ReadSourceLocation());
+  C->setModifier(static_cast<OpenMPLinearClauseKind>(Reader->Record.readInt()));
+  C->setModifierLoc(Reader->ReadSourceLocation());
   unsigned NumVars = C->varlist_size();
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setPrivates(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setInits(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setUpdates(Vars);
   Vars.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setFinals(Vars);
-  C->setStep(Reader->Reader.ReadSubExpr());
-  C->setCalcStep(Reader->Reader.ReadSubExpr());
+  C->setStep(Reader->Record.readSubExpr());
+  C->setCalcStep(Reader->Record.readSubExpr());
 }
 
 void OMPClauseReader::VisitOMPAlignedClause(OMPAlignedClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setColonLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
+  C->setColonLoc(Reader->ReadSourceLocation());
   unsigned NumVars = C->varlist_size();
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
-  C->setAlignment(Reader->Reader.ReadSubExpr());
+  C->setAlignment(Reader->Record.readSubExpr());
 }
 
 void OMPClauseReader::VisitOMPCopyinClause(OMPCopyinClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
   unsigned NumVars = C->varlist_size();
   SmallVector<Expr *, 16> Exprs;
   Exprs.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Exprs.push_back(Reader->Reader.ReadSubExpr());
+    Exprs.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Exprs);
   Exprs.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Exprs.push_back(Reader->Reader.ReadSubExpr());
+    Exprs.push_back(Reader->Record.readSubExpr());
   C->setSourceExprs(Exprs);
   Exprs.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Exprs.push_back(Reader->Reader.ReadSubExpr());
+    Exprs.push_back(Reader->Record.readSubExpr());
   C->setDestinationExprs(Exprs);
   Exprs.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Exprs.push_back(Reader->Reader.ReadSubExpr());
+    Exprs.push_back(Reader->Record.readSubExpr());
   C->setAssignmentOps(Exprs);
 }
 
 void OMPClauseReader::VisitOMPCopyprivateClause(OMPCopyprivateClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
   unsigned NumVars = C->varlist_size();
   SmallVector<Expr *, 16> Exprs;
   Exprs.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Exprs.push_back(Reader->Reader.ReadSubExpr());
+    Exprs.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Exprs);
   Exprs.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Exprs.push_back(Reader->Reader.ReadSubExpr());
+    Exprs.push_back(Reader->Record.readSubExpr());
   C->setSourceExprs(Exprs);
   Exprs.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Exprs.push_back(Reader->Reader.ReadSubExpr());
+    Exprs.push_back(Reader->Record.readSubExpr());
   C->setDestinationExprs(Exprs);
   Exprs.clear();
   for (unsigned i = 0; i != NumVars; ++i)
-    Exprs.push_back(Reader->Reader.ReadSubExpr());
+    Exprs.push_back(Reader->Record.readSubExpr());
   C->setAssignmentOps(Exprs);
 }
 
 void OMPClauseReader::VisitOMPFlushClause(OMPFlushClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
   unsigned NumVars = C->varlist_size();
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
 }
 
 void OMPClauseReader::VisitOMPDependClause(OMPDependClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setDependencyKind(static_cast<OpenMPDependClauseKind>(Record[Idx++]));
-  C->setDependencyLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setColonLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
+  C->setDependencyKind(
+      static_cast<OpenMPDependClauseKind>(Reader->Record.readInt()));
+  C->setDependencyLoc(Reader->ReadSourceLocation());
+  C->setColonLoc(Reader->ReadSourceLocation());
   unsigned NumVars = C->varlist_size();
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
-  C->setCounterValue(Reader->Reader.ReadSubExpr());
+  C->setCounterValue(Reader->Record.readSubExpr());
 }
 
 void OMPClauseReader::VisitOMPDeviceClause(OMPDeviceClause *C) {
-  C->setDevice(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setDevice(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPMapClause(OMPMapClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
   C->setMapTypeModifier(
-     static_cast<OpenMPMapClauseKind>(Record[Idx++]));
+     static_cast<OpenMPMapClauseKind>(Reader->Record.readInt()));
   C->setMapType(
-     static_cast<OpenMPMapClauseKind>(Record[Idx++]));
-  C->setMapLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setColonLoc(Reader->ReadSourceLocation(Record, Idx));
+     static_cast<OpenMPMapClauseKind>(Reader->Record.readInt()));
+  C->setMapLoc(Reader->ReadSourceLocation());
+  C->setColonLoc(Reader->ReadSourceLocation());
   auto NumVars = C->varlist_size();
   auto UniqueDecls = C->getUniqueDeclarationsNum();
   auto TotalLists = C->getTotalComponentListNum();
@@ -2283,34 +2264,32 @@ void OMPClauseReader::VisitOMPMapClause(OMPMapClause *C) {
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
 
   SmallVector<ValueDecl *, 16> Decls;
   Decls.reserve(UniqueDecls);
   for (unsigned i = 0; i < UniqueDecls; ++i)
-    Decls.push_back(
-        Reader->Reader.ReadDeclAs<ValueDecl>(Reader->F, Record, Idx));
+    Decls.push_back(Reader->Record.readDeclAs<ValueDecl>());
   C->setUniqueDecls(Decls);
 
   SmallVector<unsigned, 16> ListsPerDecl;
   ListsPerDecl.reserve(UniqueDecls);
   for (unsigned i = 0; i < UniqueDecls; ++i)
-    ListsPerDecl.push_back(Record[Idx++]);
+    ListsPerDecl.push_back(Reader->Record.readInt());
   C->setDeclNumLists(ListsPerDecl);
 
   SmallVector<unsigned, 32> ListSizes;
   ListSizes.reserve(TotalLists);
   for (unsigned i = 0; i < TotalLists; ++i)
-    ListSizes.push_back(Record[Idx++]);
+    ListSizes.push_back(Reader->Record.readInt());
   C->setComponentListSizes(ListSizes);
 
   SmallVector<OMPClauseMappableExprCommon::MappableComponent, 32> Components;
   Components.reserve(TotalComponents);
   for (unsigned i = 0; i < TotalComponents; ++i) {
-    Expr *AssociatedExpr = Reader->Reader.ReadSubExpr();
-    ValueDecl *AssociatedDecl =
-        Reader->Reader.ReadDeclAs<ValueDecl>(Reader->F, Record, Idx);
+    Expr *AssociatedExpr = Reader->Record.readSubExpr();
+    ValueDecl *AssociatedDecl = Reader->Record.readDeclAs<ValueDecl>();
     Components.push_back(OMPClauseMappableExprCommon::MappableComponent(
         AssociatedExpr, AssociatedDecl));
   }
@@ -2318,57 +2297,57 @@ void OMPClauseReader::VisitOMPMapClause(OMPMapClause *C) {
 }
 
 void OMPClauseReader::VisitOMPNumTeamsClause(OMPNumTeamsClause *C) {
-  C->setNumTeams(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setNumTeams(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPThreadLimitClause(OMPThreadLimitClause *C) {
-  C->setThreadLimit(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setThreadLimit(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPPriorityClause(OMPPriorityClause *C) {
-  C->setPriority(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setPriority(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPGrainsizeClause(OMPGrainsizeClause *C) {
-  C->setGrainsize(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setGrainsize(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPNumTasksClause(OMPNumTasksClause *C) {
-  C->setNumTasks(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setNumTasks(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPHintClause(OMPHintClause *C) {
-  C->setHint(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setHint(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPDistScheduleClause(OMPDistScheduleClause *C) {
   VisitOMPClauseWithPreInit(C);
   C->setDistScheduleKind(
-      static_cast<OpenMPDistScheduleClauseKind>(Record[Idx++]));
-  C->setChunkSize(Reader->Reader.ReadSubExpr());
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setDistScheduleKindLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setCommaLoc(Reader->ReadSourceLocation(Record, Idx));
+      static_cast<OpenMPDistScheduleClauseKind>(Reader->Record.readInt()));
+  C->setChunkSize(Reader->Record.readSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation());
+  C->setDistScheduleKindLoc(Reader->ReadSourceLocation());
+  C->setCommaLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPDefaultmapClause(OMPDefaultmapClause *C) {
   C->setDefaultmapKind(
-       static_cast<OpenMPDefaultmapClauseKind>(Record[Idx++]));
+       static_cast<OpenMPDefaultmapClauseKind>(Reader->Record.readInt()));
   C->setDefaultmapModifier(
-      static_cast<OpenMPDefaultmapClauseModifier>(Record[Idx++]));
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setDefaultmapModifierLoc(Reader->ReadSourceLocation(Record, Idx));
-  C->setDefaultmapKindLoc(Reader->ReadSourceLocation(Record, Idx));
+      static_cast<OpenMPDefaultmapClauseModifier>(Reader->Record.readInt()));
+  C->setLParenLoc(Reader->ReadSourceLocation());
+  C->setDefaultmapModifierLoc(Reader->ReadSourceLocation());
+  C->setDefaultmapKindLoc(Reader->ReadSourceLocation());
 }
 
 void OMPClauseReader::VisitOMPToClause(OMPToClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
   auto NumVars = C->varlist_size();
   auto UniqueDecls = C->getUniqueDeclarationsNum();
   auto TotalLists = C->getTotalComponentListNum();
@@ -2377,34 +2356,32 @@ void OMPClauseReader::VisitOMPToClause(OMPToClause *C) {
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
 
   SmallVector<ValueDecl *, 16> Decls;
   Decls.reserve(UniqueDecls);
   for (unsigned i = 0; i < UniqueDecls; ++i)
-    Decls.push_back(
-        Reader->Reader.ReadDeclAs<ValueDecl>(Reader->F, Record, Idx));
+    Decls.push_back(Reader->Record.readDeclAs<ValueDecl>());
   C->setUniqueDecls(Decls);
 
   SmallVector<unsigned, 16> ListsPerDecl;
   ListsPerDecl.reserve(UniqueDecls);
   for (unsigned i = 0; i < UniqueDecls; ++i)
-    ListsPerDecl.push_back(Record[Idx++]);
+    ListsPerDecl.push_back(Reader->Record.readInt());
   C->setDeclNumLists(ListsPerDecl);
 
   SmallVector<unsigned, 32> ListSizes;
   ListSizes.reserve(TotalLists);
   for (unsigned i = 0; i < TotalLists; ++i)
-    ListSizes.push_back(Record[Idx++]);
+    ListSizes.push_back(Reader->Record.readInt());
   C->setComponentListSizes(ListSizes);
 
   SmallVector<OMPClauseMappableExprCommon::MappableComponent, 32> Components;
   Components.reserve(TotalComponents);
   for (unsigned i = 0; i < TotalComponents; ++i) {
-    Expr *AssociatedExpr = Reader->Reader.ReadSubExpr();
-    ValueDecl *AssociatedDecl =
-        Reader->Reader.ReadDeclAs<ValueDecl>(Reader->F, Record, Idx);
+    Expr *AssociatedExpr = Reader->Record.readSubExpr();
+    ValueDecl *AssociatedDecl = Reader->Record.readDeclAs<ValueDecl>();
     Components.push_back(OMPClauseMappableExprCommon::MappableComponent(
         AssociatedExpr, AssociatedDecl));
   }
@@ -2412,7 +2389,7 @@ void OMPClauseReader::VisitOMPToClause(OMPToClause *C) {
 }
 
 void OMPClauseReader::VisitOMPFromClause(OMPFromClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+  C->setLParenLoc(Reader->ReadSourceLocation());
   auto NumVars = C->varlist_size();
   auto UniqueDecls = C->getUniqueDeclarationsNum();
   auto TotalLists = C->getTotalComponentListNum();
@@ -2421,34 +2398,32 @@ void OMPClauseReader::VisitOMPFromClause(OMPFromClause *C) {
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
 
   SmallVector<ValueDecl *, 16> Decls;
   Decls.reserve(UniqueDecls);
   for (unsigned i = 0; i < UniqueDecls; ++i)
-    Decls.push_back(
-        Reader->Reader.ReadDeclAs<ValueDecl>(Reader->F, Record, Idx));
+    Decls.push_back(Reader->Record.readDeclAs<ValueDecl>());
   C->setUniqueDecls(Decls);
 
   SmallVector<unsigned, 16> ListsPerDecl;
   ListsPerDecl.reserve(UniqueDecls);
   for (unsigned i = 0; i < UniqueDecls; ++i)
-    ListsPerDecl.push_back(Record[Idx++]);
+    ListsPerDecl.push_back(Reader->Record.readInt());
   C->setDeclNumLists(ListsPerDecl);
 
   SmallVector<unsigned, 32> ListSizes;
   ListSizes.reserve(TotalLists);
   for (unsigned i = 0; i < TotalLists; ++i)
-    ListSizes.push_back(Record[Idx++]);
+    ListSizes.push_back(Reader->Record.readInt());
   C->setComponentListSizes(ListSizes);
 
   SmallVector<OMPClauseMappableExprCommon::MappableComponent, 32> Components;
   Components.reserve(TotalComponents);
   for (unsigned i = 0; i < TotalComponents; ++i) {
-    Expr *AssociatedExpr = Reader->Reader.ReadSubExpr();
-    ValueDecl *AssociatedDecl =
-        Reader->Reader.ReadDeclAs<ValueDecl>(Reader->F, Record, Idx);
+    Expr *AssociatedExpr = Reader->Record.readSubExpr();
+    ValueDecl *AssociatedDecl = Reader->Record.readDeclAs<ValueDecl>();
     Components.push_back(OMPClauseMappableExprCommon::MappableComponent(
         AssociatedExpr, AssociatedDecl));
   }
@@ -2456,101 +2431,172 @@ void OMPClauseReader::VisitOMPFromClause(OMPFromClause *C) {
 }
 
 void OMPClauseReader::VisitOMPUseDevicePtrClause(OMPUseDevicePtrClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
-  unsigned NumVars = C->varlist_size();
+  C->setLParenLoc(Reader->ReadSourceLocation());
+  auto NumVars = C->varlist_size();
+  auto UniqueDecls = C->getUniqueDeclarationsNum();
+  auto TotalLists = C->getTotalComponentListNum();
+  auto TotalComponents = C->getTotalComponentsNum();
+
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
   Vars.clear();
+  for (unsigned i = 0; i != NumVars; ++i)
+    Vars.push_back(Reader->Record.readSubExpr());
+  C->setPrivateCopies(Vars);
+  Vars.clear();
+  for (unsigned i = 0; i != NumVars; ++i)
+    Vars.push_back(Reader->Record.readSubExpr());
+  C->setInits(Vars);
+
+  SmallVector<ValueDecl *, 16> Decls;
+  Decls.reserve(UniqueDecls);
+  for (unsigned i = 0; i < UniqueDecls; ++i)
+    Decls.push_back(Reader->Record.readDeclAs<ValueDecl>());
+  C->setUniqueDecls(Decls);
+
+  SmallVector<unsigned, 16> ListsPerDecl;
+  ListsPerDecl.reserve(UniqueDecls);
+  for (unsigned i = 0; i < UniqueDecls; ++i)
+    ListsPerDecl.push_back(Reader->Record.readInt());
+  C->setDeclNumLists(ListsPerDecl);
+
+  SmallVector<unsigned, 32> ListSizes;
+  ListSizes.reserve(TotalLists);
+  for (unsigned i = 0; i < TotalLists; ++i)
+    ListSizes.push_back(Reader->Record.readInt());
+  C->setComponentListSizes(ListSizes);
+
+  SmallVector<OMPClauseMappableExprCommon::MappableComponent, 32> Components;
+  Components.reserve(TotalComponents);
+  for (unsigned i = 0; i < TotalComponents; ++i) {
+    Expr *AssociatedExpr = Reader->Record.readSubExpr();
+    ValueDecl *AssociatedDecl = Reader->Record.readDeclAs<ValueDecl>();
+    Components.push_back(OMPClauseMappableExprCommon::MappableComponent(
+        AssociatedExpr, AssociatedDecl));
+  }
+  C->setComponents(Components, ListSizes);
 }
 
 void OMPClauseReader::VisitOMPIsDevicePtrClause(OMPIsDevicePtrClause *C) {
-  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
-  unsigned NumVars = C->varlist_size();
+  C->setLParenLoc(Reader->ReadSourceLocation());
+  auto NumVars = C->varlist_size();
+  auto UniqueDecls = C->getUniqueDeclarationsNum();
+  auto TotalLists = C->getTotalComponentListNum();
+  auto TotalComponents = C->getTotalComponentsNum();
+
   SmallVector<Expr *, 16> Vars;
   Vars.reserve(NumVars);
   for (unsigned i = 0; i != NumVars; ++i)
-    Vars.push_back(Reader->Reader.ReadSubExpr());
+    Vars.push_back(Reader->Record.readSubExpr());
   C->setVarRefs(Vars);
   Vars.clear();
+
+  SmallVector<ValueDecl *, 16> Decls;
+  Decls.reserve(UniqueDecls);
+  for (unsigned i = 0; i < UniqueDecls; ++i)
+    Decls.push_back(Reader->Record.readDeclAs<ValueDecl>());
+  C->setUniqueDecls(Decls);
+
+  SmallVector<unsigned, 16> ListsPerDecl;
+  ListsPerDecl.reserve(UniqueDecls);
+  for (unsigned i = 0; i < UniqueDecls; ++i)
+    ListsPerDecl.push_back(Reader->Record.readInt());
+  C->setDeclNumLists(ListsPerDecl);
+
+  SmallVector<unsigned, 32> ListSizes;
+  ListSizes.reserve(TotalLists);
+  for (unsigned i = 0; i < TotalLists; ++i)
+    ListSizes.push_back(Reader->Record.readInt());
+  C->setComponentListSizes(ListSizes);
+
+  SmallVector<OMPClauseMappableExprCommon::MappableComponent, 32> Components;
+  Components.reserve(TotalComponents);
+  for (unsigned i = 0; i < TotalComponents; ++i) {
+    Expr *AssociatedExpr = Reader->Record.readSubExpr();
+    ValueDecl *AssociatedDecl = Reader->Record.readDeclAs<ValueDecl>();
+    Components.push_back(OMPClauseMappableExprCommon::MappableComponent(
+        AssociatedExpr, AssociatedDecl));
+  }
+  C->setComponents(Components, ListSizes);
 }
 
 //===----------------------------------------------------------------------===//
 // OpenMP Directives.
 //===----------------------------------------------------------------------===//
 void ASTStmtReader::VisitOMPExecutableDirective(OMPExecutableDirective *E) {
-  E->setLocStart(ReadSourceLocation(Record, Idx));
-  E->setLocEnd(ReadSourceLocation(Record, Idx));
-  OMPClauseReader ClauseReader(this, Reader.getContext(), Record, Idx);
+  E->setLocStart(ReadSourceLocation());
+  E->setLocEnd(ReadSourceLocation());
+  OMPClauseReader ClauseReader(this, Record);
   SmallVector<OMPClause *, 5> Clauses;
   for (unsigned i = 0; i < E->getNumClauses(); ++i)
     Clauses.push_back(ClauseReader.readClause());
   E->setClauses(Clauses);
   if (E->hasAssociatedStmt())
-    E->setAssociatedStmt(Reader.ReadSubStmt());
+    E->setAssociatedStmt(Record.readSubStmt());
 }
 
 void ASTStmtReader::VisitOMPLoopDirective(OMPLoopDirective *D) {
   VisitStmt(D);
   // Two fields (NumClauses and CollapsedNum) were read in ReadStmtFromStream.
-  Idx += 2;
+  Record.skipInts(2);
   VisitOMPExecutableDirective(D);
-  D->setIterationVariable(Reader.ReadSubExpr());
-  D->setLastIteration(Reader.ReadSubExpr());
-  D->setCalcLastIteration(Reader.ReadSubExpr());
-  D->setPreCond(Reader.ReadSubExpr());
-  D->setCond(Reader.ReadSubExpr());
-  D->setInit(Reader.ReadSubExpr());
-  D->setInc(Reader.ReadSubExpr());
-  D->setPreInits(Reader.ReadSubStmt());
+  D->setIterationVariable(Record.readSubExpr());
+  D->setLastIteration(Record.readSubExpr());
+  D->setCalcLastIteration(Record.readSubExpr());
+  D->setPreCond(Record.readSubExpr());
+  D->setCond(Record.readSubExpr());
+  D->setInit(Record.readSubExpr());
+  D->setInc(Record.readSubExpr());
+  D->setPreInits(Record.readSubStmt());
   if (isOpenMPWorksharingDirective(D->getDirectiveKind()) ||
       isOpenMPTaskLoopDirective(D->getDirectiveKind()) ||
       isOpenMPDistributeDirective(D->getDirectiveKind())) {
-    D->setIsLastIterVariable(Reader.ReadSubExpr());
-    D->setLowerBoundVariable(Reader.ReadSubExpr());
-    D->setUpperBoundVariable(Reader.ReadSubExpr());
-    D->setStrideVariable(Reader.ReadSubExpr());
-    D->setEnsureUpperBound(Reader.ReadSubExpr());
-    D->setNextLowerBound(Reader.ReadSubExpr());
-    D->setNextUpperBound(Reader.ReadSubExpr());
-    D->setNumIterations(Reader.ReadSubExpr());
+    D->setIsLastIterVariable(Record.readSubExpr());
+    D->setLowerBoundVariable(Record.readSubExpr());
+    D->setUpperBoundVariable(Record.readSubExpr());
+    D->setStrideVariable(Record.readSubExpr());
+    D->setEnsureUpperBound(Record.readSubExpr());
+    D->setNextLowerBound(Record.readSubExpr());
+    D->setNextUpperBound(Record.readSubExpr());
+    D->setNumIterations(Record.readSubExpr());
   }
   if (isOpenMPLoopBoundSharingDirective(D->getDirectiveKind())) {
-    D->setPrevLowerBoundVariable(Reader.ReadSubExpr());
-    D->setPrevUpperBoundVariable(Reader.ReadSubExpr());
+    D->setPrevLowerBoundVariable(Record.readSubExpr());
+    D->setPrevUpperBoundVariable(Record.readSubExpr());
   }
   SmallVector<Expr *, 4> Sub;
   unsigned CollapsedNum = D->getCollapsedNumber();
   Sub.reserve(CollapsedNum);
   for (unsigned i = 0; i < CollapsedNum; ++i)
-    Sub.push_back(Reader.ReadSubExpr());
+    Sub.push_back(Record.readSubExpr());
   D->setCounters(Sub);
   Sub.clear();
   for (unsigned i = 0; i < CollapsedNum; ++i)
-    Sub.push_back(Reader.ReadSubExpr());
+    Sub.push_back(Record.readSubExpr());
   D->setPrivateCounters(Sub);
   Sub.clear();
   for (unsigned i = 0; i < CollapsedNum; ++i)
-    Sub.push_back(Reader.ReadSubExpr());
+    Sub.push_back(Record.readSubExpr());
   D->setInits(Sub);
   Sub.clear();
   for (unsigned i = 0; i < CollapsedNum; ++i)
-    Sub.push_back(Reader.ReadSubExpr());
+    Sub.push_back(Record.readSubExpr());
   D->setUpdates(Sub);
   Sub.clear();
   for (unsigned i = 0; i < CollapsedNum; ++i)
-    Sub.push_back(Reader.ReadSubExpr());
+    Sub.push_back(Record.readSubExpr());
   D->setFinals(Sub);
 }
 
 void ASTStmtReader::VisitOMPParallelDirective(OMPParallelDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
-  D->setHasCancel(Record[Idx++]);
+  D->setHasCancel(Record.readInt());
 }
 
 void ASTStmtReader::VisitOMPSimdDirective(OMPSimdDirective *D) {
@@ -2559,7 +2605,7 @@ void ASTStmtReader::VisitOMPSimdDirective(OMPSimdDirective *D) {
 
 void ASTStmtReader::VisitOMPForDirective(OMPForDirective *D) {
   VisitOMPLoopDirective(D);
-  D->setHasCancel(Record[Idx++]);
+  D->setHasCancel(Record.readInt());
 }
 
 void ASTStmtReader::VisitOMPForSimdDirective(OMPForSimdDirective *D) {
@@ -2569,21 +2615,21 @@ void ASTStmtReader::VisitOMPForSimdDirective(OMPForSimdDirective *D) {
 void ASTStmtReader::VisitOMPSectionsDirective(OMPSectionsDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
-  D->setHasCancel(Record[Idx++]);
+  D->setHasCancel(Record.readInt());
 }
 
 void ASTStmtReader::VisitOMPSectionDirective(OMPSectionDirective *D) {
   VisitStmt(D);
   VisitOMPExecutableDirective(D);
-  D->setHasCancel(Record[Idx++]);
+  D->setHasCancel(Record.readInt());
 }
 
 void ASTStmtReader::VisitOMPSingleDirective(OMPSingleDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
 }
 
@@ -2595,14 +2641,14 @@ void ASTStmtReader::VisitOMPMasterDirective(OMPMasterDirective *D) {
 void ASTStmtReader::VisitOMPCriticalDirective(OMPCriticalDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
-  ReadDeclarationNameInfo(D->DirName, Record, Idx);
+  ReadDeclarationNameInfo(D->DirName);
 }
 
 void ASTStmtReader::VisitOMPParallelForDirective(OMPParallelForDirective *D) {
   VisitOMPLoopDirective(D);
-  D->setHasCancel(Record[Idx++]);
+  D->setHasCancel(Record.readInt());
 }
 
 void ASTStmtReader::VisitOMPParallelForSimdDirective(
@@ -2614,17 +2660,17 @@ void ASTStmtReader::VisitOMPParallelSectionsDirective(
     OMPParallelSectionsDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
-  D->setHasCancel(Record[Idx++]);
+  D->setHasCancel(Record.readInt());
 }
 
 void ASTStmtReader::VisitOMPTaskDirective(OMPTaskDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
-  D->setHasCancel(Record[Idx++]);
+  D->setHasCancel(Record.readInt());
 }
 
 void ASTStmtReader::VisitOMPTaskyieldDirective(OMPTaskyieldDirective *D) {
@@ -2650,74 +2696,74 @@ void ASTStmtReader::VisitOMPTaskgroupDirective(OMPTaskgroupDirective *D) {
 void ASTStmtReader::VisitOMPFlushDirective(OMPFlushDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
 }
 
 void ASTStmtReader::VisitOMPOrderedDirective(OMPOrderedDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
 }
 
 void ASTStmtReader::VisitOMPAtomicDirective(OMPAtomicDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
-  D->setX(Reader.ReadSubExpr());
-  D->setV(Reader.ReadSubExpr());
-  D->setExpr(Reader.ReadSubExpr());
-  D->setUpdateExpr(Reader.ReadSubExpr());
-  D->IsXLHSInRHSPart = Record[Idx++] != 0;
-  D->IsPostfixUpdate = Record[Idx++] != 0;
+  D->setX(Record.readSubExpr());
+  D->setV(Record.readSubExpr());
+  D->setExpr(Record.readSubExpr());
+  D->setUpdateExpr(Record.readSubExpr());
+  D->IsXLHSInRHSPart = Record.readInt() != 0;
+  D->IsPostfixUpdate = Record.readInt() != 0;
 }
 
 void ASTStmtReader::VisitOMPTargetDirective(OMPTargetDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
 }
 
 void ASTStmtReader::VisitOMPTargetDataDirective(OMPTargetDataDirective *D) {
   VisitStmt(D);
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
 }
 
 void ASTStmtReader::VisitOMPTargetEnterDataDirective(
     OMPTargetEnterDataDirective *D) {
   VisitStmt(D);
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
 }
 
 void ASTStmtReader::VisitOMPTargetExitDataDirective(
     OMPTargetExitDataDirective *D) {
   VisitStmt(D);
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
 }
 
 void ASTStmtReader::VisitOMPTargetParallelDirective(
     OMPTargetParallelDirective *D) {
   VisitStmt(D);
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
 }
 
 void ASTStmtReader::VisitOMPTargetParallelForDirective(
     OMPTargetParallelForDirective *D) {
   VisitOMPLoopDirective(D);
-  D->setHasCancel(Record[Idx++]);
+  D->setHasCancel(Record.readInt());
 }
 
 void ASTStmtReader::VisitOMPTeamsDirective(OMPTeamsDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
 }
 
@@ -2725,15 +2771,15 @@ void ASTStmtReader::VisitOMPCancellationPointDirective(
     OMPCancellationPointDirective *D) {
   VisitStmt(D);
   VisitOMPExecutableDirective(D);
-  D->setCancelRegion(static_cast<OpenMPDirectiveKind>(Record[Idx++]));
+  D->setCancelRegion(static_cast<OpenMPDirectiveKind>(Record.readInt()));
 }
 
 void ASTStmtReader::VisitOMPCancelDirective(OMPCancelDirective *D) {
   VisitStmt(D);
   // The NumClauses field was read in ReadStmtFromStream.
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
-  D->setCancelRegion(static_cast<OpenMPDirectiveKind>(Record[Idx++]));
+  D->setCancelRegion(static_cast<OpenMPDirectiveKind>(Record.readInt()));
 }
 
 void ASTStmtReader::VisitOMPTaskLoopDirective(OMPTaskLoopDirective *D) {
@@ -2750,7 +2796,7 @@ void ASTStmtReader::VisitOMPDistributeDirective(OMPDistributeDirective *D) {
 
 void ASTStmtReader::VisitOMPTargetUpdateDirective(OMPTargetUpdateDirective *D) {
   VisitStmt(D);
-  ++Idx;
+  Record.skipInts(1);
   VisitOMPExecutableDirective(D);
 }
 void ASTStmtReader::VisitOMPDistributeParallelForDirective(
@@ -2773,6 +2819,47 @@ void ASTStmtReader::VisitOMPTargetParallelForSimdDirective(
   VisitOMPLoopDirective(D);
 }
 
+void ASTStmtReader::VisitOMPTargetSimdDirective(OMPTargetSimdDirective *D) {
+  VisitOMPLoopDirective(D);
+}
+
+void ASTStmtReader::VisitOMPTeamsDistributeDirective(
+    OMPTeamsDistributeDirective *D) {
+  VisitOMPLoopDirective(D);
+}
+
+void ASTStmtReader::VisitOMPTeamsDistributeSimdDirective(
+    OMPTeamsDistributeSimdDirective *D) {
+  VisitOMPLoopDirective(D);
+}
+
+void ASTStmtReader::VisitOMPTeamsDistributeParallelForSimdDirective(
+    OMPTeamsDistributeParallelForSimdDirective *D) {
+  VisitOMPLoopDirective(D);
+}
+
+void ASTStmtReader::VisitOMPTeamsDistributeParallelForDirective(
+    OMPTeamsDistributeParallelForDirective *D) {
+  VisitOMPLoopDirective(D);
+}
+
+void ASTStmtReader::VisitOMPTargetTeamsDirective(OMPTargetTeamsDirective *D) {
+  VisitStmt(D);
+  // The NumClauses field was read in ReadStmtFromStream.
+  Record.skipInts(1);
+  VisitOMPExecutableDirective(D);
+}
+
+void ASTStmtReader::VisitOMPTargetTeamsDistributeDirective(
+    OMPTargetTeamsDistributeDirective *D) {
+  VisitOMPLoopDirective(D);
+}
+
+void ASTStmtReader::VisitOMPTargetTeamsDistributeParallelForDirective(
+    OMPTargetTeamsDistributeParallelForDirective *D) {
+  VisitOMPLoopDirective(D);
+}
+
 //===----------------------------------------------------------------------===//
 // ASTReader Implementation
 //===----------------------------------------------------------------------===//
@@ -2810,7 +2897,7 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
 
   ReadingKindTracker ReadingKind(Read_Stmt, *this);
   llvm::BitstreamCursor &Cursor = F.DeclsCursor;
-  
+
   // Map of offset to previously deserialized stmt. The offset points
   /// just after the stmt record.
   llvm::DenseMap<uint64_t, Stmt *> StmtEntries;
@@ -2819,14 +2906,13 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
   unsigned PrevNumStmts = StmtStack.size();
 #endif
 
-  RecordData Record;
-  unsigned Idx;
-  ASTStmtReader Reader(*this, F, Cursor, Record, Idx);
+  ASTRecordReader Record(*this, F);
+  ASTStmtReader Reader(Record, Cursor);
   Stmt::EmptyShell Empty;
 
   while (true) {
     llvm::BitstreamEntry Entry = Cursor.advanceSkippingSubblocks();
-    
+
     switch (Entry.Kind) {
     case llvm::BitstreamEntry::SubBlock: // Handled for us already.
     case llvm::BitstreamEntry::Error:
@@ -2840,11 +2926,9 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
     }
 
     Stmt *S = nullptr;
-    Idx = 0;
-    Record.clear();
     bool Finished = false;
     bool IsStmtReference = false;
-    switch ((StmtCode)Cursor.readRecord(Entry.ID, Record)) {
+    switch ((StmtCode)Record.readRecord(Cursor, Entry.ID)) {
     case STMT_STOP:
       Finished = true;
       break;
@@ -2853,7 +2937,7 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
       IsStmtReference = true;
       assert(StmtEntries.find(Record[0]) != StmtEntries.end() &&
              "No stmt was recorded for this offset reference!");
-      S = StmtEntries[Record[Idx++]];
+      S = StmtEntries[Record.readInt()];
       break;
 
     case STMT_NULL_PTR:
@@ -2991,11 +3075,11 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
       break;
 
     case EXPR_OFFSETOF:
-      S = OffsetOfExpr::CreateEmpty(Context, 
+      S = OffsetOfExpr::CreateEmpty(Context,
                                     Record[ASTStmtReader::NumExprFields],
                                     Record[ASTStmtReader::NumExprFields + 1]);
       break;
-        
+
     case EXPR_SIZEOF_ALIGN_OF:
       S = new (Context) UnaryExprOrTypeTraitExpr(Empty);
       break;
@@ -3017,46 +3101,46 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
       // That way we can use MemberExpr::Create and don't have to duplicate its
       // logic with a MemberExpr::CreateEmpty.
 
-      assert(Idx == 0);
+      assert(Record.getIdx() == 0);
       NestedNameSpecifierLoc QualifierLoc;
-      if (Record[Idx++]) { // HasQualifier.
-        QualifierLoc = ReadNestedNameSpecifierLoc(F, Record, Idx);
+      if (Record.readInt()) { // HasQualifier.
+        QualifierLoc = Record.readNestedNameSpecifierLoc();
       }
 
       SourceLocation TemplateKWLoc;
       TemplateArgumentListInfo ArgInfo;
-      bool HasTemplateKWAndArgsInfo = Record[Idx++];
+      bool HasTemplateKWAndArgsInfo = Record.readInt();
       if (HasTemplateKWAndArgsInfo) {
-        TemplateKWLoc = ReadSourceLocation(F, Record, Idx);
-        unsigned NumTemplateArgs = Record[Idx++];
-        ArgInfo.setLAngleLoc(ReadSourceLocation(F, Record, Idx));
-        ArgInfo.setRAngleLoc(ReadSourceLocation(F, Record, Idx));
+        TemplateKWLoc = Record.readSourceLocation();
+        unsigned NumTemplateArgs = Record.readInt();
+        ArgInfo.setLAngleLoc(Record.readSourceLocation());
+        ArgInfo.setRAngleLoc(Record.readSourceLocation());
         for (unsigned i = 0; i != NumTemplateArgs; ++i)
-          ArgInfo.addArgument(ReadTemplateArgumentLoc(F, Record, Idx));
+          ArgInfo.addArgument(Record.readTemplateArgumentLoc());
       }
 
-      bool HadMultipleCandidates = Record[Idx++];
+      bool HadMultipleCandidates = Record.readInt();
 
-      NamedDecl *FoundD = ReadDeclAs<NamedDecl>(F, Record, Idx);
-      AccessSpecifier AS = (AccessSpecifier)Record[Idx++];
+      NamedDecl *FoundD = Record.readDeclAs<NamedDecl>();
+      AccessSpecifier AS = (AccessSpecifier)Record.readInt();
       DeclAccessPair FoundDecl = DeclAccessPair::make(FoundD, AS);
 
-      QualType T = readType(F, Record, Idx);
-      ExprValueKind VK = static_cast<ExprValueKind>(Record[Idx++]);
-      ExprObjectKind OK = static_cast<ExprObjectKind>(Record[Idx++]);
+      QualType T = Record.readType();
+      ExprValueKind VK = static_cast<ExprValueKind>(Record.readInt());
+      ExprObjectKind OK = static_cast<ExprObjectKind>(Record.readInt());
       Expr *Base = ReadSubExpr();
-      ValueDecl *MemberD = ReadDeclAs<ValueDecl>(F, Record, Idx);
-      SourceLocation MemberLoc = ReadSourceLocation(F, Record, Idx);
+      ValueDecl *MemberD = Record.readDeclAs<ValueDecl>();
+      SourceLocation MemberLoc = Record.readSourceLocation();
       DeclarationNameInfo MemberNameInfo(MemberD->getDeclName(), MemberLoc);
-      bool IsArrow = Record[Idx++];
-      SourceLocation OperatorLoc = ReadSourceLocation(F, Record, Idx);
+      bool IsArrow = Record.readInt();
+      SourceLocation OperatorLoc = Record.readSourceLocation();
 
       S = MemberExpr::Create(Context, Base, IsArrow, OperatorLoc, QualifierLoc,
                              TemplateKWLoc, MemberD, FoundDecl, MemberNameInfo,
                              HasTemplateKWAndArgsInfo ? &ArgInfo : nullptr, T,
                              VK, OK);
-      ReadDeclarationNameLoc(F, cast<MemberExpr>(S)->MemberDNLoc,
-                             MemberD->getDeclName(), Record, Idx);
+      Record.readDeclarationNameLoc(cast<MemberExpr>(S)->MemberDNLoc,
+                                    MemberD->getDeclName());
       if (HadMultipleCandidates)
         cast<MemberExpr>(S)->setHadMultipleCandidates(true);
       break;
@@ -3118,6 +3202,14 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
       S = new (Context) NoInitExpr(Empty);
       break;
 
+    case EXPR_ARRAY_INIT_LOOP:
+      S = new (Context) ArrayInitLoopExpr(Empty);
+      break;
+
+    case EXPR_ARRAY_INIT_INDEX:
+      S = new (Context) ArrayInitIndexExpr(Empty);
+      break;
+
     case EXPR_VA_ARG:
       S = new (Context) VAArgExpr(Empty);
       break;
@@ -3213,7 +3305,7 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
       S = new (Context) ObjCAtFinallyStmt(Empty);
       break;
     case STMT_OBJC_AT_TRY:
-      S = ObjCAtTryStmt::CreateEmpty(Context, 
+      S = ObjCAtTryStmt::CreateEmpty(Context,
                                      Record[ASTStmtReader::NumStmtFields],
                                      Record[ASTStmtReader::NumStmtFields + 1]);
       break;
@@ -3484,6 +3576,68 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
       break;
     }
 
+    case STMT_OMP_TARGET_SIMD_DIRECTIVE: {
+      auto NumClauses = Record[ASTStmtReader::NumStmtFields];
+      auto CollapsedNum = Record[ASTStmtReader::NumStmtFields + 1];
+      S = OMPTargetSimdDirective::CreateEmpty(Context, NumClauses, CollapsedNum,
+                                              Empty);
+      break;
+    }
+
+     case STMT_OMP_TEAMS_DISTRIBUTE_DIRECTIVE: {
+      auto NumClauses = Record[ASTStmtReader::NumStmtFields];
+      auto CollapsedNum = Record[ASTStmtReader::NumStmtFields + 1];
+      S = OMPTeamsDistributeDirective::CreateEmpty(Context, NumClauses,
+                                                   CollapsedNum, Empty);
+      break;
+    }
+
+    case STMT_OMP_TEAMS_DISTRIBUTE_SIMD_DIRECTIVE: {
+      unsigned NumClauses = Record[ASTStmtReader::NumStmtFields];
+      unsigned CollapsedNum = Record[ASTStmtReader::NumStmtFields + 1];
+      S = OMPTeamsDistributeSimdDirective::CreateEmpty(Context, NumClauses,
+                                                       CollapsedNum, Empty);
+      break;
+    }
+
+    case STMT_OMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_DIRECTIVE: {
+      auto NumClauses = Record[ASTStmtReader::NumStmtFields];
+      auto CollapsedNum = Record[ASTStmtReader::NumStmtFields + 1];
+      S = OMPTeamsDistributeParallelForSimdDirective::CreateEmpty(
+          Context, NumClauses, CollapsedNum, Empty);
+      break;
+    }
+
+    case STMT_OMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_DIRECTIVE: {
+      auto NumClauses = Record[ASTStmtReader::NumStmtFields];
+      auto CollapsedNum = Record[ASTStmtReader::NumStmtFields + 1];
+      S = OMPTeamsDistributeParallelForDirective::CreateEmpty(
+          Context, NumClauses, CollapsedNum, Empty);
+      break;
+    }
+
+    case STMT_OMP_TARGET_TEAMS_DIRECTIVE: {
+      S = OMPTargetTeamsDirective::CreateEmpty(
+          Context, Record[ASTStmtReader::NumStmtFields], Empty);
+      break;
+    }
+
+    case STMT_OMP_TARGET_TEAMS_DISTRIBUTE_DIRECTIVE: {
+      auto NumClauses = Record[ASTStmtReader::NumStmtFields];
+      auto CollapsedNum = Record[ASTStmtReader::NumStmtFields + 1];
+      S = OMPTargetTeamsDistributeDirective::CreateEmpty(Context, NumClauses,
+                                                         CollapsedNum, Empty);
+      break;
+    }
+
+    case STMT_OMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_DIRECTIVE: {
+      auto NumClauses = Record[ASTStmtReader::NumStmtFields];
+      auto CollapsedNum = Record[ASTStmtReader::NumStmtFields + 1];
+      S = OMPTargetTeamsDistributeParallelForDirective::CreateEmpty(
+          Context, NumClauses, CollapsedNum, Empty);
+      break;
+    }
+
     case EXPR_CXX_OPERATOR_CALL:
       S = new (Context) CXXOperatorCallExpr(Context, Empty);
       break;
@@ -3576,7 +3730,7 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
     case EXPR_CXX_BIND_TEMPORARY:
       S = new (Context) CXXBindTemporaryExpr(Empty);
       break;
-        
+
     case EXPR_CXX_SCALAR_VALUE_INIT:
       S = new (Context) CXXScalarValueInitExpr(Empty);
       break;
@@ -3589,54 +3743,54 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
     case EXPR_CXX_PSEUDO_DESTRUCTOR:
       S = new (Context) CXXPseudoDestructorExpr(Empty);
       break;
-        
+
     case EXPR_EXPR_WITH_CLEANUPS:
       S = ExprWithCleanups::Create(Context, Empty,
                                    Record[ASTStmtReader::NumExprFields]);
       break;
-      
+
     case EXPR_CXX_DEPENDENT_SCOPE_MEMBER:
       S = CXXDependentScopeMemberExpr::CreateEmpty(Context,
          /*HasTemplateKWAndArgsInfo=*/Record[ASTStmtReader::NumExprFields],
                   /*NumTemplateArgs=*/Record[ASTStmtReader::NumExprFields]
-                                   ? Record[ASTStmtReader::NumExprFields + 1] 
+                                   ? Record[ASTStmtReader::NumExprFields + 1]
                                    : 0);
       break;
-      
+
     case EXPR_CXX_DEPENDENT_SCOPE_DECL_REF:
       S = DependentScopeDeclRefExpr::CreateEmpty(Context,
          /*HasTemplateKWAndArgsInfo=*/Record[ASTStmtReader::NumExprFields],
                   /*NumTemplateArgs=*/Record[ASTStmtReader::NumExprFields]
-                                   ? Record[ASTStmtReader::NumExprFields + 1] 
+                                   ? Record[ASTStmtReader::NumExprFields + 1]
                                    : 0);
       break;
-      
+
     case EXPR_CXX_UNRESOLVED_CONSTRUCT:
       S = CXXUnresolvedConstructExpr::CreateEmpty(Context,
                               /*NumArgs=*/Record[ASTStmtReader::NumExprFields]);
       break;
-      
+
     case EXPR_CXX_UNRESOLVED_MEMBER:
       S = UnresolvedMemberExpr::CreateEmpty(Context,
          /*HasTemplateKWAndArgsInfo=*/Record[ASTStmtReader::NumExprFields],
                   /*NumTemplateArgs=*/Record[ASTStmtReader::NumExprFields]
-                                   ? Record[ASTStmtReader::NumExprFields + 1] 
+                                   ? Record[ASTStmtReader::NumExprFields + 1]
                                    : 0);
       break;
-      
+
     case EXPR_CXX_UNRESOLVED_LOOKUP:
       S = UnresolvedLookupExpr::CreateEmpty(Context,
          /*HasTemplateKWAndArgsInfo=*/Record[ASTStmtReader::NumExprFields],
                   /*NumTemplateArgs=*/Record[ASTStmtReader::NumExprFields]
-                                   ? Record[ASTStmtReader::NumExprFields + 1] 
+                                   ? Record[ASTStmtReader::NumExprFields + 1]
                                    : 0);
       break;
 
     case EXPR_TYPE_TRAIT:
-      S = TypeTraitExpr::CreateDeserialized(Context, 
+      S = TypeTraitExpr::CreateDeserialized(Context,
             Record[ASTStmtReader::NumExprFields]);
       break;
-        
+
     case EXPR_ARRAY_TYPE_TRAIT:
       S = new (Context) ArrayTypeTraitExpr(Empty);
       break;
@@ -3652,17 +3806,17 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
     case EXPR_PACK_EXPANSION:
       S = new (Context) PackExpansionExpr(Empty);
       break;
-        
+
     case EXPR_SIZEOF_PACK:
       S = SizeOfPackExpr::CreateDeserialized(
               Context,
               /*NumPartialArgs=*/Record[ASTStmtReader::NumExprFields]);
       break;
-        
+
     case EXPR_SUBST_NON_TYPE_TEMPLATE_PARM:
       S = new (Context) SubstNonTypeTemplateParmExpr(Empty);
       break;
-        
+
     case EXPR_SUBST_NON_TYPE_TEMPLATE_PARM_PACK:
       S = new (Context) SubstNonTypeTemplateParmPackExpr(Empty);
       break;
@@ -3671,7 +3825,7 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
       S = FunctionParmPackExpr::CreateEmpty(Context,
                                           Record[ASTStmtReader::NumExprFields]);
       break;
-        
+
     case EXPR_MATERIALIZE_TEMPORARY:
       S = new (Context) MaterializeTemporaryExpr(Empty);
       break;
@@ -3687,7 +3841,7 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
     case EXPR_CUDA_KERNEL_CALL:
       S = new (Context) CUDAKernelCallExpr(Context, Empty);
       break;
-        
+
     case EXPR_ASTYPE:
       S = new (Context) AsTypeExpr(Empty);
       break;
@@ -3701,16 +3855,14 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
     case EXPR_ATOMIC:
       S = new (Context) AtomicExpr(Empty);
       break;
-        
+
     case EXPR_LAMBDA: {
       unsigned NumCaptures = Record[ASTStmtReader::NumExprFields];
-      unsigned NumArrayIndexVars = Record[ASTStmtReader::NumExprFields + 1];
-      S = LambdaExpr::CreateDeserialized(Context, NumCaptures, 
-                                         NumArrayIndexVars);
+      S = LambdaExpr::CreateDeserialized(Context, NumCaptures);
       break;
     }
     }
-    
+
     // We hit a STMT_STOP, so we're done with this expression.
     if (Finished)
       break;
@@ -3722,8 +3874,8 @@ Stmt *ASTReader::ReadStmtFromStream(ModuleFile &F) {
       StmtEntries[Cursor.GetCurrentBitNo()] = S;
     }
 
-
-    assert(Idx == Record.size() && "Invalid deserialization of statement");
+    assert(Record.getIdx() == Record.size() &&
+           "Invalid deserialization of statement");
     StmtStack.push_back(S);
   }
 Done:
diff --git a/lib/Serialization/ASTWriter.cpp b/lib/Serialization/ASTWriter.cpp
index 7589b0c5dd52..6d79ea53b659 100644
--- a/lib/Serialization/ASTWriter.cpp
+++ b/lib/Serialization/ASTWriter.cpp
@@ -12,23 +12,31 @@
 //===----------------------------------------------------------------------===//
 
 #include "clang/Serialization/ASTWriter.h"
-#include "clang/Serialization/ModuleFileExtension.h"
 #include "ASTCommon.h"
 #include "ASTReaderInternals.h"
 #include "MultiOnDiskHashTable.h"
 #include "clang/AST/ASTContext.h"
+#include "clang/AST/ASTUnresolvedSet.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/DeclContextInternals.h"
+#include "clang/AST/DeclCXX.h"
 #include "clang/AST/DeclFriend.h"
-#include "clang/AST/DeclLookups.h"
 #include "clang/AST/DeclTemplate.h"
 #include "clang/AST/Expr.h"
 #include "clang/AST/ExprCXX.h"
+#include "clang/AST/LambdaCapture.h"
+#include "clang/AST/NestedNameSpecifier.h"
+#include "clang/AST/RawCommentList.h"
+#include "clang/AST/TemplateName.h"
 #include "clang/AST/Type.h"
 #include "clang/AST/TypeLocVisitor.h"
 #include "clang/Basic/DiagnosticOptions.h"
 #include "clang/Basic/FileManager.h"
-#include "clang/Basic/FileSystemStatCache.h"
+#include "clang/Basic/FileSystemOptions.h"
+#include "clang/Basic/LangOptions.h"
+#include "clang/Basic/LLVM.h"
+#include "clang/Basic/Module.h"
+#include "clang/Basic/ObjCRuntime.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Basic/SourceManagerInternals.h"
 #include "clang/Basic/TargetInfo.h"
@@ -38,28 +46,48 @@
 #include "clang/Lex/HeaderSearch.h"
 #include "clang/Lex/HeaderSearchOptions.h"
 #include "clang/Lex/MacroInfo.h"
+#include "clang/Lex/ModuleMap.h"
 #include "clang/Lex/PreprocessingRecord.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Lex/PreprocessorOptions.h"
+#include "clang/Lex/Token.h"
 #include "clang/Sema/IdentifierResolver.h"
+#include "clang/Sema/ObjCMethodList.h"
 #include "clang/Sema/Sema.h"
+#include "clang/Sema/Weak.h"
 #include "clang/Serialization/ASTReader.h"
+#include "clang/Serialization/Module.h"
+#include "clang/Serialization/ModuleFileExtension.h"
 #include "clang/Serialization/SerializationDiagnostic.h"
 #include "llvm/ADT/APFloat.h"
 #include "llvm/ADT/APInt.h"
 #include "llvm/ADT/Hashing.h"
+#include "llvm/ADT/IntrusiveRefCntPtr.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/Bitcode/BitCodes.h"
 #include "llvm/Bitcode/BitstreamWriter.h"
+#include "llvm/Support/Casting.h"
 #include "llvm/Support/Compression.h"
 #include "llvm/Support/EndianStream.h"
-#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/OnDiskHashTable.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Process.h"
+#include "llvm/Support/raw_ostream.h"
 #include <algorithm>
-#include <cstdio>
-#include <string.h>
+#include <cassert>
+#include <cstdint>
+#include <cstdlib>
+#include <cstring>
+#include <deque>
+#include <limits>
+#include <new>
+#include <tuple>
 #include <utility>
 
 using namespace clang;
@@ -83,6 +111,7 @@ static StringRef bytes(const SmallVectorImpl<T> &v) {
 //===----------------------------------------------------------------------===//
 
 namespace clang {
+
   class ASTTypeWriter {
     ASTWriter &Writer;
     ASTRecordWriter Record;
@@ -127,6 +156,7 @@ namespace clang {
 #define ABSTRACT_TYPE(Class, Base)
 #include "clang/AST/TypeNodes.def"
   };
+
 } // end namespace clang
 
 void ASTTypeWriter::VisitBuiltinType(const BuiltinType *T) {
@@ -451,6 +481,14 @@ void ASTTypeWriter::VisitObjCInterfaceType(const ObjCInterfaceType *T) {
   Code = TYPE_OBJC_INTERFACE;
 }
 
+void ASTTypeWriter::VisitObjCTypeParamType(const ObjCTypeParamType *T) {
+  Record.AddDeclRef(T->getDecl());
+  Record.push_back(T->getNumProtocols());
+  for (const auto *I : T->quals())
+    Record.AddDeclRef(I);
+  Code = TYPE_OBJC_TYPE_PARAM;
+}
+
 void ASTTypeWriter::VisitObjCObjectType(const ObjCObjectType *T) {
   Record.AddTypeRef(T->getBaseType());
   Record.push_back(T->getTypeArgsAsWritten().size());
@@ -478,6 +516,7 @@ ASTTypeWriter::VisitAtomicType(const AtomicType *T) {
 void
 ASTTypeWriter::VisitPipeType(const PipeType *T) {
   Record.AddTypeRef(T->getElementType());
+  Record.push_back(T->isReadOnly());
   Code = TYPE_PIPE;
 }
 
@@ -504,6 +543,7 @@ public:
 void TypeLocWriter::VisitQualifiedTypeLoc(QualifiedTypeLoc TL) {
   // nothing to do
 }
+
 void TypeLocWriter::VisitBuiltinTypeLoc(BuiltinTypeLoc TL) {
   Record.AddSourceLocation(TL.getBuiltinLoc());
   if (TL.needsExtraLocalData()) {
@@ -513,31 +553,40 @@ void TypeLocWriter::VisitBuiltinTypeLoc(BuiltinTypeLoc TL) {
     Record.push_back(TL.hasModeAttr());
   }
 }
+
 void TypeLocWriter::VisitComplexTypeLoc(ComplexTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitPointerTypeLoc(PointerTypeLoc TL) {
   Record.AddSourceLocation(TL.getStarLoc());
 }
+
 void TypeLocWriter::VisitDecayedTypeLoc(DecayedTypeLoc TL) {
   // nothing to do
 }
+
 void TypeLocWriter::VisitAdjustedTypeLoc(AdjustedTypeLoc TL) {
   // nothing to do
 }
+
 void TypeLocWriter::VisitBlockPointerTypeLoc(BlockPointerTypeLoc TL) {
   Record.AddSourceLocation(TL.getCaretLoc());
 }
+
 void TypeLocWriter::VisitLValueReferenceTypeLoc(LValueReferenceTypeLoc TL) {
   Record.AddSourceLocation(TL.getAmpLoc());
 }
+
 void TypeLocWriter::VisitRValueReferenceTypeLoc(RValueReferenceTypeLoc TL) {
   Record.AddSourceLocation(TL.getAmpAmpLoc());
 }
+
 void TypeLocWriter::VisitMemberPointerTypeLoc(MemberPointerTypeLoc TL) {
   Record.AddSourceLocation(TL.getStarLoc());
   Record.AddTypeSourceInfo(TL.getClassTInfo());
 }
+
 void TypeLocWriter::VisitArrayTypeLoc(ArrayTypeLoc TL) {
   Record.AddSourceLocation(TL.getLBracketLoc());
   Record.AddSourceLocation(TL.getRBracketLoc());
@@ -545,29 +594,37 @@ void TypeLocWriter::VisitArrayTypeLoc(ArrayTypeLoc TL) {
   if (TL.getSizeExpr())
     Record.AddStmt(TL.getSizeExpr());
 }
+
 void TypeLocWriter::VisitConstantArrayTypeLoc(ConstantArrayTypeLoc TL) {
   VisitArrayTypeLoc(TL);
 }
+
 void TypeLocWriter::VisitIncompleteArrayTypeLoc(IncompleteArrayTypeLoc TL) {
   VisitArrayTypeLoc(TL);
 }
+
 void TypeLocWriter::VisitVariableArrayTypeLoc(VariableArrayTypeLoc TL) {
   VisitArrayTypeLoc(TL);
 }
+
 void TypeLocWriter::VisitDependentSizedArrayTypeLoc(
                                             DependentSizedArrayTypeLoc TL) {
   VisitArrayTypeLoc(TL);
 }
+
 void TypeLocWriter::VisitDependentSizedExtVectorTypeLoc(
                                         DependentSizedExtVectorTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitVectorTypeLoc(VectorTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitExtVectorTypeLoc(ExtVectorTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitFunctionTypeLoc(FunctionTypeLoc TL) {
   Record.AddSourceLocation(TL.getLocalRangeBegin());
   Record.AddSourceLocation(TL.getLParenLoc());
@@ -588,35 +645,50 @@ void TypeLocWriter::VisitUnresolvedUsingTypeLoc(UnresolvedUsingTypeLoc TL) {
 void TypeLocWriter::VisitTypedefTypeLoc(TypedefTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+void TypeLocWriter::VisitObjCTypeParamTypeLoc(ObjCTypeParamTypeLoc TL) {
+  if (TL.getNumProtocols()) {
+    Record.AddSourceLocation(TL.getProtocolLAngleLoc());
+    Record.AddSourceLocation(TL.getProtocolRAngleLoc());
+  }
+  for (unsigned i = 0, e = TL.getNumProtocols(); i != e; ++i)
+    Record.AddSourceLocation(TL.getProtocolLoc(i));
+}
 void TypeLocWriter::VisitTypeOfExprTypeLoc(TypeOfExprTypeLoc TL) {
   Record.AddSourceLocation(TL.getTypeofLoc());
   Record.AddSourceLocation(TL.getLParenLoc());
   Record.AddSourceLocation(TL.getRParenLoc());
 }
+
 void TypeLocWriter::VisitTypeOfTypeLoc(TypeOfTypeLoc TL) {
   Record.AddSourceLocation(TL.getTypeofLoc());
   Record.AddSourceLocation(TL.getLParenLoc());
   Record.AddSourceLocation(TL.getRParenLoc());
   Record.AddTypeSourceInfo(TL.getUnderlyingTInfo());
 }
+
 void TypeLocWriter::VisitDecltypeTypeLoc(DecltypeTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitUnaryTransformTypeLoc(UnaryTransformTypeLoc TL) {
   Record.AddSourceLocation(TL.getKWLoc());
   Record.AddSourceLocation(TL.getLParenLoc());
   Record.AddSourceLocation(TL.getRParenLoc());
   Record.AddTypeSourceInfo(TL.getUnderlyingTInfo());
 }
+
 void TypeLocWriter::VisitAutoTypeLoc(AutoTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitRecordTypeLoc(RecordTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitEnumTypeLoc(EnumTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitAttributedTypeLoc(AttributedTypeLoc TL) {
   Record.AddSourceLocation(TL.getAttrNameLoc());
   if (TL.hasAttrOperand()) {
@@ -632,17 +704,21 @@ void TypeLocWriter::VisitAttributedTypeLoc(AttributedTypeLoc TL) {
     Record.AddSourceLocation(TL.getAttrEnumOperandLoc());
   }
 }
+
 void TypeLocWriter::VisitTemplateTypeParmTypeLoc(TemplateTypeParmTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitSubstTemplateTypeParmTypeLoc(
                                             SubstTemplateTypeParmTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitSubstTemplateTypeParmPackTypeLoc(
                                           SubstTemplateTypeParmPackTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitTemplateSpecializationTypeLoc(
                                            TemplateSpecializationTypeLoc TL) {
   Record.AddSourceLocation(TL.getTemplateKeywordLoc());
@@ -653,22 +729,27 @@ void TypeLocWriter::VisitTemplateSpecializationTypeLoc(
     Record.AddTemplateArgumentLocInfo(TL.getArgLoc(i).getArgument().getKind(),
                                       TL.getArgLoc(i).getLocInfo());
 }
+
 void TypeLocWriter::VisitParenTypeLoc(ParenTypeLoc TL) {
   Record.AddSourceLocation(TL.getLParenLoc());
   Record.AddSourceLocation(TL.getRParenLoc());
 }
+
 void TypeLocWriter::VisitElaboratedTypeLoc(ElaboratedTypeLoc TL) {
   Record.AddSourceLocation(TL.getElaboratedKeywordLoc());
   Record.AddNestedNameSpecifierLoc(TL.getQualifierLoc());
 }
+
 void TypeLocWriter::VisitInjectedClassNameTypeLoc(InjectedClassNameTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitDependentNameTypeLoc(DependentNameTypeLoc TL) {
   Record.AddSourceLocation(TL.getElaboratedKeywordLoc());
   Record.AddNestedNameSpecifierLoc(TL.getQualifierLoc());
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitDependentTemplateSpecializationTypeLoc(
        DependentTemplateSpecializationTypeLoc TL) {
   Record.AddSourceLocation(TL.getElaboratedKeywordLoc());
@@ -681,12 +762,15 @@ void TypeLocWriter::VisitDependentTemplateSpecializationTypeLoc(
     Record.AddTemplateArgumentLocInfo(TL.getArgLoc(I).getArgument().getKind(),
                                       TL.getArgLoc(I).getLocInfo());
 }
+
 void TypeLocWriter::VisitPackExpansionTypeLoc(PackExpansionTypeLoc TL) {
   Record.AddSourceLocation(TL.getEllipsisLoc());
 }
+
 void TypeLocWriter::VisitObjCInterfaceTypeLoc(ObjCInterfaceTypeLoc TL) {
   Record.AddSourceLocation(TL.getNameLoc());
 }
+
 void TypeLocWriter::VisitObjCObjectTypeLoc(ObjCObjectTypeLoc TL) {
   Record.push_back(TL.hasBaseTypeAsWritten());
   Record.AddSourceLocation(TL.getTypeArgsLAngleLoc());
@@ -698,14 +782,17 @@ void TypeLocWriter::VisitObjCObjectTypeLoc(ObjCObjectTypeLoc TL) {
   for (unsigned i = 0, e = TL.getNumProtocols(); i != e; ++i)
     Record.AddSourceLocation(TL.getProtocolLoc(i));
 }
+
 void TypeLocWriter::VisitObjCObjectPointerTypeLoc(ObjCObjectPointerTypeLoc TL) {
   Record.AddSourceLocation(TL.getStarLoc());
 }
+
 void TypeLocWriter::VisitAtomicTypeLoc(AtomicTypeLoc TL) {
   Record.AddSourceLocation(TL.getKWLoc());
   Record.AddSourceLocation(TL.getLParenLoc());
   Record.AddSourceLocation(TL.getRParenLoc());
 }
+
 void TypeLocWriter::VisitPipeTypeLoc(PipeTypeLoc TL) {
   Record.AddSourceLocation(TL.getKWLoc());
 }
@@ -905,7 +992,7 @@ static void AddStmtsExprs(llvm::BitstreamWriter &Stream,
 
 void ASTWriter::WriteBlockInfoBlock() {
   RecordData Record;
-  Stream.EnterSubblock(llvm::bitc::BLOCKINFO_BLOCK_ID, 3);
+  Stream.EnterBlockInfoBlock();
 
 #define BLOCK(X) EmitBlockID(X ## _ID, #X, Stream, Record)
 #define RECORD(X) EmitRecordID(X, #X, Stream, Record)
@@ -966,6 +1053,8 @@ void ASTWriter::WriteBlockInfoBlock() {
   RECORD(HEADER_SEARCH_TABLE);
   RECORD(FP_PRAGMA_OPTIONS);
   RECORD(OPENCL_EXTENSIONS);
+  RECORD(OPENCL_EXTENSION_TYPES);
+  RECORD(OPENCL_EXTENSION_DECLS);
   RECORD(DELEGATING_CTORS);
   RECORD(KNOWN_NAMESPACES);
   RECORD(MODULE_OFFSET_MAP);
@@ -983,6 +1072,7 @@ void ASTWriter::WriteBlockInfoBlock() {
   RECORD(POINTERS_TO_MEMBERS_PRAGMA_OPTIONS);
   RECORD(UNUSED_LOCAL_TYPEDEF_NAME_CANDIDATES);
   RECORD(DELETE_EXPRS_TO_ANALYZE);
+  RECORD(CUDA_PRAGMA_FORCE_HOST_DEVICE_DEPTH);
 
   // SourceManager Block.
   BLOCK(SOURCE_MANAGER_BLOCK);
@@ -1018,6 +1108,7 @@ void ASTWriter::WriteBlockInfoBlock() {
   RECORD(SUBMODULE_PRIVATE_HEADER);
   RECORD(SUBMODULE_TEXTUAL_HEADER);
   RECORD(SUBMODULE_PRIVATE_TEXTUAL_HEADER);
+  RECORD(SUBMODULE_INITIALIZERS);
 
   // Comments Block.
   BLOCK(COMMENTS_BLOCK);
@@ -1066,6 +1157,7 @@ void ASTWriter::WriteBlockInfoBlock() {
   RECORD(TYPE_ATOMIC);
   RECORD(TYPE_DECAYED);
   RECORD(TYPE_ADJUSTED);
+  RECORD(TYPE_OBJC_TYPE_PARAM);
   RECORD(LOCAL_REDECLARATIONS);
   RECORD(DECL_TYPEDEF);
   RECORD(DECL_TYPEALIAS);
@@ -1212,7 +1304,7 @@ adjustFilenameForRelocatableAST(const char *Filename, StringRef BaseDir) {
 }
 
 static ASTFileSignature getSignature() {
-  while (1) {
+  while (true) {
     if (ASTFileSignature S = llvm::sys::Process::GetRandomNumber())
       return S;
     // Rely on GetRandomNumber to eventually return non-zero...
@@ -1534,6 +1626,7 @@ uint64_t ASTWriter::WriteControlBlock(Preprocessor &PP,
 }
 
 namespace  {
+
   /// \brief An input file.
   struct InputFileEntry {
     const FileEntry *File;
@@ -1541,6 +1634,7 @@ namespace  {
     bool IsTransient;
     bool BufferOverridden;
   };
+
 } // end anonymous namespace
 
 void ASTWriter::WriteInputFiles(SourceManager &SourceMgr,
@@ -1701,6 +1795,7 @@ static unsigned CreateSLocExpansionAbbrev(llvm::BitstreamWriter &Stream) {
 }
 
 namespace {
+
   // Trait used for the on-disk hash table of header search information.
   class HeaderFileInfoTrait {
     ASTWriter &Writer;
@@ -1716,7 +1811,7 @@ namespace {
     
     struct key_type {
       const FileEntry *FE;
-      const char *Filename;
+      StringRef Filename;
     };
     typedef const key_type &key_type_ref;
     
@@ -1737,7 +1832,7 @@ namespace {
     EmitKeyDataLength(raw_ostream& Out, key_type_ref key, data_type_ref Data) {
       using namespace llvm::support;
       endian::Writer<little> LE(Out);
-      unsigned KeyLen = strlen(key.Filename) + 1 + 8 + 8;
+      unsigned KeyLen = key.Filename.size() + 1 + 8 + 8;
       LE.write<uint16_t>(KeyLen);
       unsigned DataLen = 1 + 2 + 4 + 4;
       for (auto ModInfo : HS.getModuleMap().findAllModulesForHeader(key.FE))
@@ -1754,7 +1849,7 @@ namespace {
       KeyLen -= 8;
       LE.write<uint64_t>(Writer.getTimestampForOutput(key.FE));
       KeyLen -= 8;
-      Out.write(key.Filename, KeyLen);
+      Out.write(key.Filename.data(), KeyLen);
     }
     
     void EmitData(raw_ostream &Out, key_type_ref key,
@@ -1809,6 +1904,7 @@ namespace {
     const char *strings_begin() const { return FrameworkStringData.begin(); }
     const char *strings_end() const { return FrameworkStringData.end(); }
   };
+
 } // end anonymous namespace
 
 /// \brief Write the header search block for the list of files that 
@@ -1842,13 +1938,13 @@ void ASTWriter::WriteHeaderSearch(const HeaderSearch &HS) {
       continue;
 
     // Massage the file path into an appropriate form.
-    const char *Filename = File->getName();
+    StringRef Filename = File->getName();
     SmallString<128> FilenameTmp(Filename);
     if (PreparePathForOutput(FilenameTmp)) {
       // If we performed any translation on the file name at all, we need to
       // save this string, since the generator will refer to it later.
-      Filename = strdup(FilenameTmp.c_str());
-      SavedStrings.push_back(Filename);
+      Filename = StringRef(strdup(FilenameTmp.c_str()));
+      SavedStrings.push_back(Filename.data());
     }
 
     HeaderFileInfoTrait::key_type key = { File, Filename };
@@ -1982,14 +2078,13 @@ void ASTWriter::WriteSourceManagerBlock(SourceManager &SourceMgr,
         // the reader side).
         const llvm::MemoryBuffer *Buffer
           = Content->getBuffer(PP.getDiagnostics(), PP.getSourceManager());
-        const char *Name = Buffer->getBufferIdentifier();
+        StringRef Name = Buffer->getBufferIdentifier();
         Stream.EmitRecordWithBlob(SLocBufferAbbrv, Record,
-                                  StringRef(Name, strlen(Name) + 1));
+                                  StringRef(Name.data(), Name.size() + 1));
         EmitBlob = true;
 
-        if (strcmp(Name, "<built-in>") == 0) {
+        if (Name == "<built-in>")
           PreloadSLocs.push_back(SLocEntryOffsets.size());
-        }
       }
 
       if (EmitBlob) {
@@ -2418,7 +2513,9 @@ unsigned ASTWriter::getLocalOrImportedSubmoduleID(Module *Mod) {
   if (Known != SubmoduleIDs.end())
     return Known->second;
 
-  if (Mod->getTopLevelModule() != WritingModule)
+  auto *Top = Mod->getTopLevelModule();
+  if (Top != WritingModule &&
+      !Top->fullModuleNameIs(StringRef(getLangOpts().CurrentModule)))
     return 0;
 
   return SubmoduleIDs[Mod] = NextSubmoduleID++;
@@ -2650,6 +2747,13 @@ void ASTWriter::WriteSubmodules(Module *WritingModule) {
       Stream.EmitRecordWithBlob(ConfigMacroAbbrev, Record, CM);
     }
 
+    // Emit the initializers, if any.
+    RecordData Inits;
+    for (Decl *D : Context->getModuleInitializers(Mod))
+      Inits.push_back(GetDeclRef(D));
+    if (!Inits.empty())
+      Stream.EmitRecord(SUBMODULE_INITIALIZERS, Inits);
+
     // Queue up the submodules of this module.
     for (auto *M : Mod->submodules())
       Q.push(M);
@@ -2860,6 +2964,7 @@ void ASTWriter::WriteComments() {
 //===----------------------------------------------------------------------===//
 
 namespace {
+
 // Trait used for the on-disk hash table used in the method pool.
 class ASTMethodPoolTrait {
   ASTWriter &Writer;
@@ -2964,6 +3069,7 @@ public:
     assert(Out.tell() - Start == DataLen && "Data length is wrong");
   }
 };
+
 } // end anonymous namespace
 
 /// \brief Write ObjC data: selectors and the method pool.
@@ -3135,6 +3241,7 @@ static NamedDecl *getDeclForLocalLookup(const LangOptions &LangOpts,
 }
 
 namespace {
+
 class ASTIdentifierTableTrait {
   ASTWriter &Writer;
   Preprocessor &PP;
@@ -3185,6 +3292,7 @@ public:
     auto MacroOffset = Writer.getMacroDirectivesOffset(II);
     return isInterestingIdentifier(II, MacroOffset);
   }
+
   bool isInterestingNonMacroIdentifier(const IdentifierInfo *II) {
     return isInterestingIdentifier(II, 0);
   }
@@ -3278,6 +3386,7 @@ public:
     }
   }
 };
+
 } // end anonymous namespace
 
 /// \brief Write the identifier table into the AST file.
@@ -3384,6 +3493,7 @@ void ASTWriter::WriteIdentifierTable(Preprocessor &PP,
 //===----------------------------------------------------------------------===//
 
 namespace {
+
 // Trait used for the on-disk hash table used in the method pool.
 class ASTDeclContextNameLookupTrait {
   ASTWriter &Writer;
@@ -3509,6 +3619,7 @@ public:
     assert(Out.tell() - Start == DataLen && "Data length is wrong");
   }
 };
+
 } // end anonymous namespace
 
 bool ASTWriter::isLookupResultExternal(StoredDeclsList &Result,
@@ -3830,11 +3941,53 @@ void ASTWriter::WriteOpenCLExtensions(Sema &SemaRef) {
 
   const OpenCLOptions &Opts = SemaRef.getOpenCLOptions();
   RecordData Record;
-#define OPENCLEXT(nm)  Record.push_back(Opts.nm);
-#include "clang/Basic/OpenCLExtensions.def"
+  for (const auto &I:Opts.OptMap) {
+    AddString(I.getKey(), Record);
+    auto V = I.getValue();
+    Record.push_back(V.Supported ? 1 : 0);
+    Record.push_back(V.Enabled ? 1 : 0);
+    Record.push_back(V.Avail);
+    Record.push_back(V.Core);
+  }
   Stream.EmitRecord(OPENCL_EXTENSIONS, Record);
 }
 
+void ASTWriter::WriteOpenCLExtensionTypes(Sema &SemaRef) {
+  if (!SemaRef.Context.getLangOpts().OpenCL)
+    return;
+
+  RecordData Record;
+  for (const auto &I : SemaRef.OpenCLTypeExtMap) {
+    Record.push_back(
+        static_cast<unsigned>(getTypeID(I.first->getCanonicalTypeInternal())));
+    Record.push_back(I.second.size());
+    for (auto Ext : I.second)
+      AddString(Ext, Record);
+  }
+  Stream.EmitRecord(OPENCL_EXTENSION_TYPES, Record);
+}
+
+void ASTWriter::WriteOpenCLExtensionDecls(Sema &SemaRef) {
+  if (!SemaRef.Context.getLangOpts().OpenCL)
+    return;
+
+  RecordData Record;
+  for (const auto &I : SemaRef.OpenCLDeclExtMap) {
+    Record.push_back(getDeclID(I.first));
+    Record.push_back(static_cast<unsigned>(I.second.size()));
+    for (auto Ext : I.second)
+      AddString(Ext, Record);
+  }
+  Stream.EmitRecord(OPENCL_EXTENSION_DECLS, Record);
+}
+
+void ASTWriter::WriteCUDAPragmas(Sema &SemaRef) {
+  if (SemaRef.ForceCUDAHostDeviceDepth > 0) {
+    RecordData::value_type Record[] = {SemaRef.ForceCUDAHostDeviceDepth};
+    Stream.EmitRecord(CUDA_PRAGMA_FORCE_HOST_DEVICE_DEPTH, Record);
+  }
+}
+
 void ASTWriter::WriteObjCCategories() {
   SmallVector<ObjCCategoriesInfo, 2> CategoriesMap;
   RecordData Categories;
@@ -3894,14 +4047,14 @@ void ASTWriter::WriteLateParsedTemplates(Sema &SemaRef) {
     return;
 
   RecordData Record;
-  for (auto LPTMapEntry : LPTMap) {
+  for (auto &LPTMapEntry : LPTMap) {
     const FunctionDecl *FD = LPTMapEntry.first;
-    LateParsedTemplate *LPT = LPTMapEntry.second;
+    LateParsedTemplate &LPT = *LPTMapEntry.second;
     AddDeclRef(FD, Record);
-    AddDeclRef(LPT->D, Record);
-    Record.push_back(LPT->Toks.size());
+    AddDeclRef(LPT.D, Record);
+    Record.push_back(LPT.Toks.size());
 
-    for (const auto &Tok : LPT->Toks) {
+    for (const auto &Tok : LPT.Toks) {
       AddToken(Tok, Record);
     }
   }
@@ -4255,9 +4408,10 @@ uint64_t ASTWriter::WriteASTCore(Sema &SemaRef, StringRef isysroot,
 
   // Build a record containing some declaration references.
   RecordData SemaDeclRefs;
-  if (SemaRef.StdNamespace || SemaRef.StdBadAlloc) {
+  if (SemaRef.StdNamespace || SemaRef.StdBadAlloc || SemaRef.StdAlignValT) {
     AddDeclRef(SemaRef.getStdNamespace(), SemaDeclRefs);
     AddDeclRef(SemaRef.getStdBadAlloc(), SemaDeclRefs);
+    AddDeclRef(SemaRef.getStdAlignValT(), SemaDeclRefs);
   }
 
   RecordData CUDASpecialDeclRefs;
@@ -4364,8 +4518,9 @@ uint64_t ASTWriter::WriteASTCore(Sema &SemaRef, StringRef isysroot,
                                                      Number.second));
 
   // Make sure visible decls, added to DeclContexts previously loaded from
-  // an AST file, are registered for serialization.
-  for (const auto *I : UpdatingVisibleDecls) {
+  // an AST file, are registered for serialization. Likewise for template
+  // specializations added to imported templates.
+  for (const auto *I : DeclsToEmitEvenIfUnreferenced) {
     GetDeclRef(I);
   }
 
@@ -4510,11 +4665,25 @@ uint64_t ASTWriter::WriteASTCore(Sema &SemaRef, StringRef isysroot,
   WriteIdentifierTable(PP, SemaRef.IdResolver, isModule);
   WriteFPPragmaOptions(SemaRef.getFPOptions());
   WriteOpenCLExtensions(SemaRef);
+  WriteOpenCLExtensionTypes(SemaRef);
+  WriteOpenCLExtensionDecls(SemaRef);
+  WriteCUDAPragmas(SemaRef);
   WritePragmaDiagnosticMappings(Context.getDiagnostics(), isModule);
 
   // If we're emitting a module, write out the submodule information.  
   if (WritingModule)
     WriteSubmodules(WritingModule);
+  else if (!getLangOpts().CurrentModule.empty()) {
+    // If we're building a PCH in the implementation of a module, we may need
+    // the description of the current module.
+    //
+    // FIXME: We may need other modules that we did not load from an AST file,
+    // such as if a module declares a 'conflicts' on a different module.
+    Module *M = PP.getHeaderSearchInfo().getModuleMap().findModule(
+        getLangOpts().CurrentModule);
+    if (M && !M->IsFromModuleFile)
+      WriteSubmodules(M);
+  }
 
   Stream.EmitRecord(SPECIAL_TYPES, SpecialTypes);
 
@@ -4682,6 +4851,11 @@ void ASTWriter::WriteDeclUpdatesBlocks(RecordDataImpl &OffsetsRecord) {
             cast<ParmVarDecl>(Update.getDecl())->getDefaultArg()));
         break;
 
+      case UPD_CXX_INSTANTIATED_DEFAULT_MEMBER_INITIALIZER:
+        Record.AddStmt(
+            cast<FieldDecl>(Update.getDecl())->getInClassInitializer());
+        break;
+
       case UPD_CXX_INSTANTIATED_CLASS_DEFINITION: {
         auto *RD = cast<CXXRecordDecl>(D);
         UpdatedDeclContexts.insert(RD->getPrimaryContext());
@@ -5159,7 +5333,7 @@ void ASTRecordWriter::AddDeclarationNameInfo(
 void ASTRecordWriter::AddQualifierInfo(const QualifierInfo &Info) {
   AddNestedNameSpecifierLoc(Info.QualifierLoc);
   Record->push_back(Info.NumTemplParamLists);
-  for (unsigned i=0, e=Info.NumTemplParamLists; i != e; ++i)
+  for (unsigned i = 0, e = Info.NumTemplParamLists; i != e; ++i)
     AddTemplateParameterList(Info.TemplParamLists[i]);
 }
 
@@ -5361,6 +5535,7 @@ void ASTRecordWriter::AddTemplateParameterList(
   AddSourceLocation(TemplateParams->getTemplateLoc());
   AddSourceLocation(TemplateParams->getLAngleLoc());
   AddSourceLocation(TemplateParams->getRAngleLoc());
+  // TODO: Concepts
   Record->push_back(TemplateParams->size());
   for (const auto &P : *TemplateParams)
     AddDeclRef(P);
@@ -5371,7 +5546,7 @@ void ASTRecordWriter::AddTemplateArgumentList(
     const TemplateArgumentList *TemplateArgs) {
   assert(TemplateArgs && "No TemplateArgs!");
   Record->push_back(TemplateArgs->size());
-  for (int i=0, e = TemplateArgs->size(); i != e; ++i)
+  for (int i = 0, e = TemplateArgs->size(); i != e; ++i)
     AddTemplateArgument(TemplateArgs->get(i));
 }
 
@@ -5382,7 +5557,7 @@ void ASTRecordWriter::AddASTTemplateArgumentListInfo(
   AddSourceLocation(ASTTemplArgList->RAngleLoc);
   Record->push_back(ASTTemplArgList->NumTemplateArgs);
   const TemplateArgumentLoc *TemplArgs = ASTTemplArgList->getTemplateArgs();
-  for (int i=0, e = ASTTemplArgList->NumTemplateArgs; i != e; ++i)
+  for (int i = 0, e = ASTTemplArgList->NumTemplateArgs; i != e; ++i)
     AddTemplateArgumentLoc(TemplArgs[i]);
 }
 
@@ -5452,13 +5627,8 @@ EmitCXXCtorInitializers(ASTWriter &W,
     Writer.AddSourceLocation(Init->getLParenLoc());
     Writer.AddSourceLocation(Init->getRParenLoc());
     Writer.push_back(Init->isWritten());
-    if (Init->isWritten()) {
+    if (Init->isWritten())
       Writer.push_back(Init->getSourceOrder());
-    } else {
-      Writer.push_back(Init->getNumArrayIndices());
-      for (auto *VD : Init->getArrayIndices())
-        Writer.AddDeclRef(VD);
-    }
   }
 
   return Writer.Emit(serialization::DECL_CXX_CTOR_INITIALIZERS);
@@ -5539,7 +5709,7 @@ void ASTRecordWriter::AddCXXDefinitionData(const CXXRecordDecl *D) {
     Record->push_back(Lambda.NumCaptures);
     Record->push_back(Lambda.NumExplicitCaptures);
     Record->push_back(Lambda.ManglingNumber);
-    AddDeclRef(Lambda.ContextDecl);
+    AddDeclRef(D->getLambdaContextDecl());
     AddTypeSourceInfo(Lambda.MethodTyInfo);
     for (unsigned I = 0, N = Lambda.NumCaptures; I != N; ++I) {
       const LambdaCapture &Capture = Lambda.Captures[I];
@@ -5693,9 +5863,9 @@ void ASTWriter::AddedVisibleDecl(const DeclContext *DC, const Decl *D) {
     // that we write out all of its lookup results so we don't get a nasty
     // surprise when we try to emit its lookup table.
     for (auto *Child : DC->decls())
-      UpdatingVisibleDecls.push_back(Child);
+      DeclsToEmitEvenIfUnreferenced.push_back(Child);
   }
-  UpdatingVisibleDecls.push_back(D);
+  DeclsToEmitEvenIfUnreferenced.push_back(D);
 }
 
 void ASTWriter::AddedCXXImplicitMember(const CXXRecordDecl *RD, const Decl *D) {
@@ -5794,6 +5964,15 @@ void ASTWriter::DefaultArgumentInstantiated(const ParmVarDecl *D) {
       DeclUpdate(UPD_CXX_INSTANTIATED_DEFAULT_ARGUMENT, D));
 }
 
+void ASTWriter::DefaultMemberInitializerInstantiated(const FieldDecl *D) {
+  assert(!WritingAST && "Already writing the AST!");
+  if (!D->isFromASTFile())
+    return;
+
+  DeclUpdates[D].push_back(
+      DeclUpdate(UPD_CXX_INSTANTIATED_DEFAULT_MEMBER_INITIALIZER, D));
+}
+
 void ASTWriter::AddedObjCCategoryToInterface(const ObjCCategoryDecl *CatD,
                                              const ObjCInterfaceDecl *IFD) {
   if (Chain && Chain->isProcessingUpdateRecords()) return;
@@ -5855,3 +6034,39 @@ void ASTWriter::AddedAttributeToRecord(const Attr *Attr,
     return;
   DeclUpdates[Record].push_back(DeclUpdate(UPD_ADDED_ATTR_TO_RECORD, Attr));
 }
+
+void ASTWriter::AddedCXXTemplateSpecialization(
+    const ClassTemplateDecl *TD, const ClassTemplateSpecializationDecl *D) {
+  assert(!WritingAST && "Already writing the AST!");
+
+  if (!TD->getFirstDecl()->isFromASTFile())
+    return;
+  if (Chain && Chain->isProcessingUpdateRecords())
+    return;
+
+  DeclsToEmitEvenIfUnreferenced.push_back(D);
+}
+
+void ASTWriter::AddedCXXTemplateSpecialization(
+    const VarTemplateDecl *TD, const VarTemplateSpecializationDecl *D) {
+  assert(!WritingAST && "Already writing the AST!");
+
+  if (!TD->getFirstDecl()->isFromASTFile())
+    return;
+  if (Chain && Chain->isProcessingUpdateRecords())
+    return;
+
+  DeclsToEmitEvenIfUnreferenced.push_back(D);
+}
+
+void ASTWriter::AddedCXXTemplateSpecialization(const FunctionTemplateDecl *TD,
+                                               const FunctionDecl *D) {
+  assert(!WritingAST && "Already writing the AST!");
+
+  if (!TD->getFirstDecl()->isFromASTFile())
+    return;
+  if (Chain && Chain->isProcessingUpdateRecords())
+    return;
+
+  DeclsToEmitEvenIfUnreferenced.push_back(D);
+}
diff --git a/lib/Serialization/ASTWriterDecl.cpp b/lib/Serialization/ASTWriterDecl.cpp
index 23d18540e822..ee220f00a81f 100644
--- a/lib/Serialization/ASTWriterDecl.cpp
+++ b/lib/Serialization/ASTWriterDecl.cpp
@@ -11,7 +11,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "clang/Serialization/ASTWriter.h"
 #include "ASTCommon.h"
 #include "clang/AST/DeclCXX.h"
 #include "clang/AST/DeclContextInternals.h"
@@ -20,7 +19,7 @@
 #include "clang/AST/Expr.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Serialization/ASTReader.h"
-#include "llvm/ADT/Twine.h"
+#include "clang/Serialization/ASTWriter.h"
 #include "llvm/Bitcode/BitstreamWriter.h"
 #include "llvm/Support/ErrorHandling.h"
 using namespace clang;
@@ -97,6 +96,8 @@ namespace clang {
     void VisitVarDecl(VarDecl *D);
     void VisitImplicitParamDecl(ImplicitParamDecl *D);
     void VisitParmVarDecl(ParmVarDecl *D);
+    void VisitDecompositionDecl(DecompositionDecl *D);
+    void VisitBindingDecl(BindingDecl *D);
     void VisitNonTypeTemplateParmDecl(NonTypeTemplateParmDecl *D);
     void VisitTemplateDecl(TemplateDecl *D);
     void VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D);
@@ -106,9 +107,11 @@ namespace clang {
     void VisitTemplateTemplateParmDecl(TemplateTemplateParmDecl *D);
     void VisitTypeAliasTemplateDecl(TypeAliasTemplateDecl *D);
     void VisitUsingDecl(UsingDecl *D);
+    void VisitUsingPackDecl(UsingPackDecl *D);
     void VisitUsingShadowDecl(UsingShadowDecl *D);
     void VisitConstructorUsingShadowDecl(ConstructorUsingShadowDecl *D);
     void VisitLinkageSpecDecl(LinkageSpecDecl *D);
+    void VisitExportDecl(ExportDecl *D);
     void VisitFileScopeAsmDecl(FileScopeAsmDecl *D);
     void VisitImportDecl(ImportDecl *D);
     void VisitAccessSpecDecl(AccessSpecDecl *D);
@@ -892,6 +895,7 @@ void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
   Record.push_back(D->getTSCSpec());
   Record.push_back(D->getInitStyle());
   if (!isa<ParmVarDecl>(D)) {
+    Record.push_back(D->isThisDeclarationADemotedDefinition());
     Record.push_back(D->isExceptionVariable());
     Record.push_back(D->isNRVOVariable());
     Record.push_back(D->isCXXForRangeDecl());
@@ -940,10 +944,7 @@ void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
       D->getDeclName().getNameKind() == DeclarationName::Identifier &&
       !D->hasExtInfo() &&
       D->getFirstDecl() == D->getMostRecentDecl() &&
-      D->getInitStyle() == VarDecl::CInit &&
-      D->getInit() == nullptr &&
-      !isa<ParmVarDecl>(D) &&
-      !isa<VarTemplateSpecializationDecl>(D) &&
+      D->getKind() == Decl::Var &&
       !D->isInline() &&
       !D->isConstexpr() &&
       !D->isInitCapture() &&
@@ -999,6 +1000,8 @@ void ASTDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
   // Check things we know are true of *every* PARM_VAR_DECL, which is more than
   // just us assuming it.
   assert(!D->getTSCSpec() && "PARM_VAR_DECL can't use TLS");
+  assert(!D->isThisDeclarationADemotedDefinition()
+         && "PARM_VAR_DECL can't be demoted definition.");
   assert(D->getAccess() == AS_none && "PARM_VAR_DECL can't be public/private");
   assert(!D->isExceptionVariable() && "PARM_VAR_DECL can't be exception var");
   assert(D->getPreviousDecl() == nullptr && "PARM_VAR_DECL can't be redecl");
@@ -1006,6 +1009,22 @@ void ASTDeclWriter::VisitParmVarDecl(ParmVarDecl *D) {
          "PARM_VAR_DECL can't be static data member");
 }
 
+void ASTDeclWriter::VisitDecompositionDecl(DecompositionDecl *D) {
+  // Record the number of bindings first to simplify deserialization.
+  Record.push_back(D->bindings().size());
+
+  VisitVarDecl(D);
+  for (auto *B : D->bindings())
+    Record.AddDeclRef(B);
+  Code = serialization::DECL_DECOMPOSITION;
+}
+
+void ASTDeclWriter::VisitBindingDecl(BindingDecl *D) {
+  VisitValueDecl(D);
+  Record.AddStmt(D->getBinding());
+  Code = serialization::DECL_BINDING;
+}
+
 void ASTDeclWriter::VisitFileScopeAsmDecl(FileScopeAsmDecl *D) {
   VisitDecl(D);
   Record.AddStmt(D->getAsmString());
@@ -1064,6 +1083,12 @@ void ASTDeclWriter::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
   Code = serialization::DECL_LINKAGE_SPEC;
 }
 
+void ASTDeclWriter::VisitExportDecl(ExportDecl *D) {
+  VisitDecl(D);
+  Record.AddSourceLocation(D->getRBraceLoc());
+  Code = serialization::DECL_EXPORT;
+}
+
 void ASTDeclWriter::VisitLabelDecl(LabelDecl *D) {
   VisitNamedDecl(D);
   Record.AddSourceLocation(D->getLocStart());
@@ -1118,6 +1143,15 @@ void ASTDeclWriter::VisitUsingDecl(UsingDecl *D) {
   Code = serialization::DECL_USING;
 }
 
+void ASTDeclWriter::VisitUsingPackDecl(UsingPackDecl *D) {
+  Record.push_back(D->NumExpansions);
+  VisitNamedDecl(D);
+  Record.AddDeclRef(D->getInstantiatedFromUsingDecl());
+  for (auto *E : D->expansions())
+    Record.AddDeclRef(E);
+  Code = serialization::DECL_USING_PACK;
+}
+
 void ASTDeclWriter::VisitUsingShadowDecl(UsingShadowDecl *D) {
   VisitRedeclarable(D);
   VisitNamedDecl(D);
@@ -1151,6 +1185,7 @@ void ASTDeclWriter::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
   Record.AddSourceLocation(D->getUsingLoc());
   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
   Record.AddDeclarationNameLoc(D->DNLoc, D->getDeclName());
+  Record.AddSourceLocation(D->getEllipsisLoc());
   Code = serialization::DECL_UNRESOLVED_USING_VALUE;
 }
 
@@ -1159,6 +1194,7 @@ void ASTDeclWriter::VisitUnresolvedUsingTypenameDecl(
   VisitTypeDecl(D);
   Record.AddSourceLocation(D->getTypenameLoc());
   Record.AddNestedNameSpecifierLoc(D->getQualifierLoc());
+  Record.AddSourceLocation(D->getEllipsisLoc());
   Code = serialization::DECL_UNRESOLVED_USING_TYPENAME;
 }
 
@@ -1857,9 +1893,9 @@ void ASTWriter::WriteDeclAbbrevs() {
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
   // VarDecl
-  Abv->Add(BitCodeAbbrevOp(0));                       // StorageClass
-  Abv->Add(BitCodeAbbrevOp(0));                       // getTSCSpec
-  Abv->Add(BitCodeAbbrevOp(0));                       // hasCXXDirectInitializer
+  Abv->Add(BitCodeAbbrevOp(0));                       // SClass
+  Abv->Add(BitCodeAbbrevOp(0));                       // TSCSpec
+  Abv->Add(BitCodeAbbrevOp(0));                       // InitStyle
   Abv->Add(BitCodeAbbrevOp(0));                       // Linkage
   Abv->Add(BitCodeAbbrevOp(0));                       // HasInit
   Abv->Add(BitCodeAbbrevOp(0));                   // HasMemberSpecializationInfo
@@ -1933,9 +1969,10 @@ void ASTWriter::WriteDeclAbbrevs() {
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // InnerStartLoc
   Abv->Add(BitCodeAbbrevOp(0));                       // hasExtInfo
   // VarDecl
-  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // StorageClass
-  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // getTSCSpec
-  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // CXXDirectInitializer
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // SClass
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // TSCSpec
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // InitStyle
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // IsThisDeclarationADemotedDefinition
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isExceptionVariable
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isNRVOVariable
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isCXXForRangeDecl
@@ -1946,8 +1983,8 @@ void ASTWriter::WriteDeclAbbrevs() {
   Abv->Add(BitCodeAbbrevOp(0));                         // isInitCapture
   Abv->Add(BitCodeAbbrevOp(0));                         // isPrevDeclInSameScope
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3)); // Linkage
-  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasInit
-  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // HasMemberSpecInfo
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // IsInitICE (local)
+  Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 2)); // VarKind (local enum)
   // Type Source Info
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
@@ -2123,11 +2160,11 @@ static bool isRequiredDecl(const Decl *D, ASTContext &Context,
       D->hasAttr<OMPDeclareTargetDeclAttr>())
     return true;
 
-  // ImportDecl is used by codegen to determine the set of imported modules to
-  // search for inputs for automatic linking; include it if it has a semantic
-  // effect.
-  if (isa<ImportDecl>(D) && !WritingModule)
-    return true;
+  if (WritingModule && (isa<VarDecl>(D) || isa<ImportDecl>(D))) {
+    // These declarations are part of the module initializer, and are emitted
+    // if and when the module is imported, rather than being emitted eagerly.
+    return false;
+  }
 
   return Context.DeclMustBeEmitted(D);
 }
diff --git a/lib/Serialization/ASTWriterStmt.cpp b/lib/Serialization/ASTWriterStmt.cpp
index 84e718e9ef23..3993be146edf 100644
--- a/lib/Serialization/ASTWriterStmt.cpp
+++ b/lib/Serialization/ASTWriterStmt.cpp
@@ -792,6 +792,18 @@ void ASTStmtWriter::VisitNoInitExpr(NoInitExpr *E) {
   Code = serialization::EXPR_NO_INIT;
 }
 
+void ASTStmtWriter::VisitArrayInitLoopExpr(ArrayInitLoopExpr *E) {
+  VisitExpr(E);
+  Record.AddStmt(E->SubExprs[0]);
+  Record.AddStmt(E->SubExprs[1]);
+  Code = serialization::EXPR_ARRAY_INIT_LOOP;
+}
+
+void ASTStmtWriter::VisitArrayInitIndexExpr(ArrayInitIndexExpr *E) {
+  VisitExpr(E);
+  Code = serialization::EXPR_ARRAY_INIT_INDEX;
+}
+
 void ASTStmtWriter::VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
   VisitExpr(E);
   Code = serialization::EXPR_IMPLICIT_VALUE_INIT;
@@ -1245,10 +1257,6 @@ void ASTStmtWriter::VisitCXXTemporaryObjectExpr(CXXTemporaryObjectExpr *E) {
 void ASTStmtWriter::VisitLambdaExpr(LambdaExpr *E) {
   VisitExpr(E);
   Record.push_back(E->NumCaptures);
-  unsigned NumArrayIndexVars = 0;
-  if (E->HasArrayIndexVars)
-    NumArrayIndexVars = E->getArrayIndexStarts()[E->NumCaptures];
-  Record.push_back(NumArrayIndexVars);
   Record.AddSourceRange(E->IntroducerRange);
   Record.push_back(E->CaptureDefault); // FIXME: stable encoding
   Record.AddSourceLocation(E->CaptureDefaultLoc);
@@ -1263,15 +1271,6 @@ void ASTStmtWriter::VisitLambdaExpr(LambdaExpr *E) {
     Record.AddStmt(*C);
   }
   
-  // Add array index variables, if any.
-  if (NumArrayIndexVars) {
-    Record.append(E->getArrayIndexStarts(), 
-                  E->getArrayIndexStarts() + E->NumCaptures + 1);
-    VarDecl **ArrayIndexVars = E->getArrayIndexVars();
-    for (unsigned I = 0; I != NumArrayIndexVars; ++I)
-      Record.AddDeclRef(ArrayIndexVars[I]);
-  }
-  
   Code = serialization::EXPR_LAMBDA;
 }
 
@@ -1392,6 +1391,7 @@ void ASTStmtWriter::VisitCXXNewExpr(CXXNewExpr *E) {
   VisitExpr(E);
   Record.push_back(E->isGlobalNew());
   Record.push_back(E->isArray());
+  Record.push_back(E->passAlignment());
   Record.push_back(E->doesUsualArrayDeleteWantSize());
   Record.push_back(E->getNumPlacementArgs());
   Record.push_back(E->StoredInitializationStyle);
@@ -1576,6 +1576,7 @@ void ASTStmtWriter::VisitArrayTypeTraitExpr(ArrayTypeTraitExpr *E) {
   Record.push_back(E->getValue());
   Record.AddSourceRange(E->getSourceRange());
   Record.AddTypeSourceInfo(E->getQueriedTypeSourceInfo());
+  Record.AddStmt(E->getDimensionExpression());
   Code = serialization::EXPR_ARRAY_TYPE_TRAIT;
 }
 
@@ -2151,17 +2152,45 @@ void OMPClauseWriter::VisitOMPFromClause(OMPFromClause *C) {
 
 void OMPClauseWriter::VisitOMPUseDevicePtrClause(OMPUseDevicePtrClause *C) {
   Record.push_back(C->varlist_size());
+  Record.push_back(C->getUniqueDeclarationsNum());
+  Record.push_back(C->getTotalComponentListNum());
+  Record.push_back(C->getTotalComponentsNum());
   Record.AddSourceLocation(C->getLParenLoc());
-  for (auto *VE : C->varlists()) {
+  for (auto *E : C->varlists())
+    Record.AddStmt(E);
+  for (auto *VE : C->private_copies())
+    Record.AddStmt(VE);
+  for (auto *VE : C->inits())
     Record.AddStmt(VE);
+  for (auto *D : C->all_decls())
+    Record.AddDeclRef(D);
+  for (auto N : C->all_num_lists())
+    Record.push_back(N);
+  for (auto N : C->all_lists_sizes())
+    Record.push_back(N);
+  for (auto &M : C->all_components()) {
+    Record.AddStmt(M.getAssociatedExpression());
+    Record.AddDeclRef(M.getAssociatedDeclaration());
   }
 }
 
 void OMPClauseWriter::VisitOMPIsDevicePtrClause(OMPIsDevicePtrClause *C) {
   Record.push_back(C->varlist_size());
+  Record.push_back(C->getUniqueDeclarationsNum());
+  Record.push_back(C->getTotalComponentListNum());
+  Record.push_back(C->getTotalComponentsNum());
   Record.AddSourceLocation(C->getLParenLoc());
-  for (auto *VE : C->varlists()) {
-    Record.AddStmt(VE);
+  for (auto *E : C->varlists())
+    Record.AddStmt(E);
+  for (auto *D : C->all_decls())
+    Record.AddDeclRef(D);
+  for (auto N : C->all_num_lists())
+    Record.push_back(N);
+  for (auto N : C->all_lists_sizes())
+    Record.push_back(N);
+  for (auto &M : C->all_components()) {
+    Record.AddStmt(M.getAssociatedExpression());
+    Record.AddDeclRef(M.getAssociatedDeclaration());
   }
 }
 
@@ -2479,6 +2508,54 @@ void ASTStmtWriter::VisitOMPTargetParallelForSimdDirective(
   Code = serialization::STMT_OMP_TARGET_PARALLEL_FOR_SIMD_DIRECTIVE;
 }
 
+void ASTStmtWriter::VisitOMPTargetSimdDirective(OMPTargetSimdDirective *D) {
+  VisitOMPLoopDirective(D);
+  Code = serialization::STMT_OMP_TARGET_SIMD_DIRECTIVE;
+}
+
+void ASTStmtWriter::VisitOMPTeamsDistributeDirective(
+    OMPTeamsDistributeDirective *D) {
+  VisitOMPLoopDirective(D);
+  Code = serialization::STMT_OMP_TEAMS_DISTRIBUTE_DIRECTIVE;
+}
+
+void ASTStmtWriter::VisitOMPTeamsDistributeSimdDirective(
+    OMPTeamsDistributeSimdDirective *D) {
+  VisitOMPLoopDirective(D);
+  Code = serialization::STMT_OMP_TEAMS_DISTRIBUTE_SIMD_DIRECTIVE;
+}
+
+void ASTStmtWriter::VisitOMPTeamsDistributeParallelForSimdDirective(
+    OMPTeamsDistributeParallelForSimdDirective *D) {
+  VisitOMPLoopDirective(D);
+  Code = serialization::STMT_OMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_DIRECTIVE;
+}
+
+void ASTStmtWriter::VisitOMPTeamsDistributeParallelForDirective(
+    OMPTeamsDistributeParallelForDirective *D) {
+  VisitOMPLoopDirective(D);
+  Code = serialization::STMT_OMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_DIRECTIVE;
+}
+
+void ASTStmtWriter::VisitOMPTargetTeamsDirective(OMPTargetTeamsDirective *D) {
+  VisitStmt(D);
+  Record.push_back(D->getNumClauses());
+  VisitOMPExecutableDirective(D);
+  Code = serialization::STMT_OMP_TARGET_TEAMS_DIRECTIVE;
+}
+
+void ASTStmtWriter::VisitOMPTargetTeamsDistributeDirective(
+    OMPTargetTeamsDistributeDirective *D) {
+  VisitOMPLoopDirective(D);
+  Code = serialization::STMT_OMP_TARGET_TEAMS_DISTRIBUTE_DIRECTIVE;
+}
+
+void ASTStmtWriter::VisitOMPTargetTeamsDistributeParallelForDirective(
+    OMPTargetTeamsDistributeParallelForDirective *D) {
+  VisitOMPLoopDirective(D);
+  Code = serialization::STMT_OMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_DIRECTIVE;
+}
+
 //===----------------------------------------------------------------------===//
 // ASTWriter Implementation
 //===----------------------------------------------------------------------===//
diff --git a/lib/Serialization/GeneratePCH.cpp b/lib/Serialization/GeneratePCH.cpp
index 308fde8b1dd7..e1765dafd96f 100644
--- a/lib/Serialization/GeneratePCH.cpp
+++ b/lib/Serialization/GeneratePCH.cpp
@@ -12,24 +12,21 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "clang/Serialization/ASTWriter.h"
-#include "clang/AST/ASTConsumer.h"
 #include "clang/AST/ASTContext.h"
-#include "clang/Basic/FileManager.h"
+#include "clang/Lex/HeaderSearch.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Sema/SemaConsumer.h"
+#include "clang/Serialization/ASTWriter.h"
 #include "llvm/Bitcode/BitstreamWriter.h"
-#include <string>
 
 using namespace clang;
 
 PCHGenerator::PCHGenerator(
-  const Preprocessor &PP, StringRef OutputFile,
-  clang::Module *Module, StringRef isysroot,
-  std::shared_ptr<PCHBuffer> Buffer,
-  ArrayRef<llvm::IntrusiveRefCntPtr<ModuleFileExtension>> Extensions,
-  bool AllowASTWithErrors, bool IncludeTimestamps)
-    : PP(PP), OutputFile(OutputFile), Module(Module), isysroot(isysroot.str()),
+    const Preprocessor &PP, StringRef OutputFile, StringRef isysroot,
+    std::shared_ptr<PCHBuffer> Buffer,
+    ArrayRef<llvm::IntrusiveRefCntPtr<ModuleFileExtension>> Extensions,
+    bool AllowASTWithErrors, bool IncludeTimestamps)
+    : PP(PP), OutputFile(OutputFile), isysroot(isysroot.str()),
       SemaPtr(nullptr), Buffer(Buffer), Stream(Buffer->Data),
       Writer(Stream, Extensions, IncludeTimestamps),
       AllowASTWithErrors(AllowASTWithErrors) {
@@ -48,6 +45,16 @@ void PCHGenerator::HandleTranslationUnit(ASTContext &Ctx) {
   if (hasErrors && !AllowASTWithErrors)
     return;
 
+  Module *Module = nullptr;
+  if (PP.getLangOpts().isCompilingModule()) {
+    Module = PP.getHeaderSearchInfo().lookupModule(
+        PP.getLangOpts().CurrentModule, /*AllowSearch*/ false);
+    if (!Module) {
+      assert(hasErrors && "emitting module but current module doesn't exist");
+      return;
+    }
+  }
+
   // Emit the PCH file to the Buffer.
   assert(SemaPtr && "No Sema?");
   Buffer->Signature =
diff --git a/lib/Serialization/GlobalModuleIndex.cpp b/lib/Serialization/GlobalModuleIndex.cpp
index 581e894d9150..9f986d54a989 100644
--- a/lib/Serialization/GlobalModuleIndex.cpp
+++ b/lib/Serialization/GlobalModuleIndex.cpp
@@ -245,12 +245,8 @@ GlobalModuleIndex::readIndex(StringRef Path) {
     return std::make_pair(nullptr, EC_NotFound);
   std::unique_ptr<llvm::MemoryBuffer> Buffer = std::move(BufferOrErr.get());
 
-  /// \brief The bitstream reader from which we'll read the AST file.
-  llvm::BitstreamReader Reader((const unsigned char *)Buffer->getBufferStart(),
-                               (const unsigned char *)Buffer->getBufferEnd());
-
   /// \brief The main bitstream cursor for the main block.
-  llvm::BitstreamCursor Cursor(Reader);
+  llvm::BitstreamCursor Cursor(*Buffer);
 
   // Sniff for the signature.
   if (Cursor.Read(8) != 'B' ||
@@ -460,7 +456,7 @@ static void emitRecordID(unsigned ID, const char *Name,
 void
 GlobalModuleIndexBuilder::emitBlockInfoBlock(llvm::BitstreamWriter &Stream) {
   SmallVector<uint64_t, 64> Record;
-  Stream.EnterSubblock(llvm::bitc::BLOCKINFO_BLOCK_ID, 3);
+  Stream.EnterBlockInfoBlock();
 
 #define BLOCK(X) emitBlockID(X ## _ID, #X, Stream, Record)
 #define RECORD(X) emitRecordID(X, #X, Stream, Record)
@@ -504,9 +500,7 @@ bool GlobalModuleIndexBuilder::loadModuleFile(const FileEntry *File) {
   }
 
   // Initialize the input stream
-  llvm::BitstreamReader InStreamFile;
-  PCHContainerRdr.ExtractPCH((*Buffer)->getMemBufferRef(), InStreamFile);
-  llvm::BitstreamCursor InStream(InStreamFile);
+  llvm::BitstreamCursor InStream(PCHContainerRdr.ExtractPCH(**Buffer));
 
   // Sniff for the signature.
   if (InStream.Read(8) != 'C' ||
diff --git a/lib/Serialization/Module.cpp b/lib/Serialization/Module.cpp
index ca0cb3c8ea17..72b08610bb4d 100644
--- a/lib/Serialization/Module.cpp
+++ b/lib/Serialization/Module.cpp
@@ -13,7 +13,6 @@
 //===----------------------------------------------------------------------===//
 #include "clang/Serialization/Module.h"
 #include "ASTReaderInternals.h"
-#include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/raw_ostream.h"
 
 using namespace clang;
diff --git a/lib/Serialization/ModuleFileExtension.cpp b/lib/Serialization/ModuleFileExtension.cpp
index 81dcfd60ce8e..5bd0a1ce660b 100644
--- a/lib/Serialization/ModuleFileExtension.cpp
+++ b/lib/Serialization/ModuleFileExtension.cpp
@@ -8,7 +8,6 @@
 //===----------------------------------------------------------------------===//
 #include "clang/Serialization/ModuleFileExtension.h"
 #include "llvm/ADT/Hashing.h"
-#include "llvm/Support/raw_ostream.h"
 using namespace clang;
 
 ModuleFileExtension::~ModuleFileExtension() { }
diff --git a/lib/Serialization/ModuleManager.cpp b/lib/Serialization/ModuleManager.cpp
index 292f36dfeb2a..722b547e803e 100644
--- a/lib/Serialization/ModuleManager.cpp
+++ b/lib/Serialization/ModuleManager.cpp
@@ -11,14 +11,13 @@
 //  modules for the ASTReader.
 //
 //===----------------------------------------------------------------------===//
+#include "clang/Serialization/ModuleManager.h"
 #include "clang/Frontend/PCHContainerOperations.h"
 #include "clang/Lex/HeaderSearch.h"
 #include "clang/Lex/ModuleMap.h"
 #include "clang/Serialization/GlobalModuleIndex.h"
-#include "clang/Serialization/ModuleManager.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Path.h"
-#include "llvm/Support/raw_ostream.h"
 #include <system_error>
 
 #ifndef NDEBUG
@@ -67,7 +66,7 @@ ModuleManager::addModule(StringRef FileName, ModuleKind Type,
   // Look for the file entry. This only fails if the expected size or
   // modification time differ.
   const FileEntry *Entry;
-  if (Type == MK_ExplicitModule) {
+  if (Type == MK_ExplicitModule || Type == MK_PrebuiltModule) {
     // If we're not expecting to pull this file out of the module cache, it
     // might have a different mtime due to being moved across filesystems in
     // a distributed build. The size must still match, though. (As must the
@@ -85,37 +84,31 @@ ModuleManager::addModule(StringRef FileName, ModuleKind Type,
   }
 
   // Check whether we already loaded this module, before
-  ModuleFile *&ModuleEntry = Modules[Entry];
+  ModuleFile *ModuleEntry = Modules[Entry];
   bool NewModule = false;
   if (!ModuleEntry) {
     // Allocate a new module.
-    ModuleFile *New = new ModuleFile(Type, Generation);
-    New->Index = Chain.size();
-    New->FileName = FileName.str();
-    New->File = Entry;
-    New->ImportLoc = ImportLoc;
-    Chain.push_back(New);
-    if (!New->isModule())
-      PCHChain.push_back(New);
-    if (!ImportedBy)
-      Roots.push_back(New);
     NewModule = true;
-    ModuleEntry = New;
-
-    New->InputFilesValidationTimestamp = 0;
-    if (New->Kind == MK_ImplicitModule) {
-      std::string TimestampFilename = New->getTimestampFilename();
+    ModuleEntry = new ModuleFile(Type, Generation);
+    ModuleEntry->Index = Chain.size();
+    ModuleEntry->FileName = FileName.str();
+    ModuleEntry->File = Entry;
+    ModuleEntry->ImportLoc = ImportLoc;
+    ModuleEntry->InputFilesValidationTimestamp = 0;
+
+    if (ModuleEntry->Kind == MK_ImplicitModule) {
+      std::string TimestampFilename = ModuleEntry->getTimestampFilename();
       vfs::Status Status;
       // A cached stat value would be fine as well.
       if (!FileMgr.getNoncachedStatValue(TimestampFilename, Status))
-        New->InputFilesValidationTimestamp =
-            Status.getLastModificationTime().toEpochTime();
+        ModuleEntry->InputFilesValidationTimestamp =
+            llvm::sys::toTimeT(Status.getLastModificationTime());
     }
 
     // Load the contents of the module
     if (std::unique_ptr<llvm::MemoryBuffer> Buffer = lookupBuffer(FileName)) {
       // The buffer was already provided for us.
-      New->Buffer = std::move(Buffer);
+      ModuleEntry->Buffer = std::move(Buffer);
     } else {
       // Open the AST file.
       llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> Buf(
@@ -127,52 +120,40 @@ ModuleManager::addModule(StringRef FileName, ModuleKind Type,
         // ModuleManager it must be the same underlying file.
         // FIXME: Because FileManager::getFile() doesn't guarantee that it will
         // give us an open file, this may not be 100% reliable.
-        Buf = FileMgr.getBufferForFile(New->File,
+        Buf = FileMgr.getBufferForFile(ModuleEntry->File,
                                        /*IsVolatile=*/false,
                                        /*ShouldClose=*/false);
       }
 
       if (!Buf) {
         ErrorStr = Buf.getError().message();
+        delete ModuleEntry;
         return Missing;
       }
 
-      New->Buffer = std::move(*Buf);
+      ModuleEntry->Buffer = std::move(*Buf);
     }
 
     // Initialize the stream.
-    PCHContainerRdr.ExtractPCH(New->Buffer->getMemBufferRef(), New->StreamFile);
+    ModuleEntry->Data = PCHContainerRdr.ExtractPCH(*ModuleEntry->Buffer);
   }
 
   if (ExpectedSignature) {
-    if (NewModule)
-      ModuleEntry->Signature = ReadSignature(ModuleEntry->StreamFile);
-    else
-      assert(ModuleEntry->Signature == ReadSignature(ModuleEntry->StreamFile));
+    // If we've not read the control block yet, read the signature eagerly now
+    // so that we can check it.
+    if (!ModuleEntry->Signature)
+      ModuleEntry->Signature = ReadSignature(ModuleEntry->Data);
 
     if (ModuleEntry->Signature != ExpectedSignature) {
       ErrorStr = ModuleEntry->Signature ? "signature mismatch"
                                         : "could not read module signature";
 
-      if (NewModule) {
-        // Remove the module file immediately, since removeModules might try to
-        // invalidate the file cache for Entry, and that is not safe if this
-        // module is *itself* up to date, but has an out-of-date importer.
-        Modules.erase(Entry);
-        assert(Chain.back() == ModuleEntry);
-        Chain.pop_back();
-        if (!ModuleEntry->isModule())
-          PCHChain.pop_back();
-        if (Roots.back() == ModuleEntry)
-          Roots.pop_back();
-        else
-          assert(ImportedBy);
+      if (NewModule)
         delete ModuleEntry;
-      }
       return OutOfDate;
     }
   }
-  
+
   if (ImportedBy) {
     ModuleEntry->ImportedBy.insert(ImportedBy);
     ImportedBy->Imports.insert(ModuleEntry);
@@ -184,7 +165,20 @@ ModuleManager::addModule(StringRef FileName, ModuleKind Type,
   }
 
   Module = ModuleEntry;
-  return NewModule? NewlyLoaded : AlreadyLoaded;
+
+  if (!NewModule)
+    return AlreadyLoaded;
+
+  assert(!Modules[Entry] && "module loaded twice");
+  Modules[Entry] = ModuleEntry;
+
+  Chain.push_back(ModuleEntry);
+  if (!ModuleEntry->isModule())
+    PCHChain.push_back(ModuleEntry);
+  if (!ImportedBy)
+    Roots.push_back(ModuleEntry);
+
+  return NewlyLoaded;
 }
 
 void ModuleManager::removeModules(
@@ -413,13 +407,16 @@ bool ModuleManager::lookupModuleFile(StringRef FileName,
                                      off_t ExpectedSize,
                                      time_t ExpectedModTime,
                                      const FileEntry *&File) {
+  if (FileName == "-") {
+    File = nullptr;
+    return false;
+  }
+
   // Open the file immediately to ensure there is no race between stat'ing and
   // opening the file.
   File = FileMgr.getFile(FileName, /*openFile=*/true, /*cacheFailure=*/false);
-
-  if (!File && FileName != "-") {
+  if (!File)
     return false;
-  }
 
   if ((ExpectedSize && ExpectedSize != File->getSize()) ||
       (ExpectedModTime && ExpectedModTime != File->getModificationTime()))
@@ -434,15 +431,15 @@ bool ModuleManager::lookupModuleFile(StringRef FileName,
 namespace llvm {
   template<>
   struct GraphTraits<ModuleManager> {
-    typedef ModuleFile NodeType;
+    typedef ModuleFile *NodeRef;
     typedef llvm::SetVector<ModuleFile *>::const_iterator ChildIteratorType;
     typedef ModuleManager::ModuleConstIterator nodes_iterator;
-    
-    static ChildIteratorType child_begin(NodeType *Node) {
+
+    static ChildIteratorType child_begin(NodeRef Node) {
       return Node->Imports.begin();
     }
 
-    static ChildIteratorType child_end(NodeType *Node) {
+    static ChildIteratorType child_end(NodeRef Node) {
       return Node->Imports.end();
     }
     
diff --git a/lib/Serialization/MultiOnDiskHashTable.h b/lib/Serialization/MultiOnDiskHashTable.h
index 04dea831695c..fdbbb602b537 100644
--- a/lib/Serialization/MultiOnDiskHashTable.h
+++ b/lib/Serialization/MultiOnDiskHashTable.h
@@ -18,7 +18,11 @@
 #ifndef LLVM_CLANG_LIB_SERIALIZATION_MULTIONDISKHASHTABLE_H
 #define LLVM_CLANG_LIB_SERIALIZATION_MULTIONDISKHASHTABLE_H
 
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/PointerUnion.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/TinyPtrVector.h"
 #include "llvm/Support/EndianStream.h"
 #include "llvm/Support/OnDiskHashTable.h"