Vendor import of clang r114020 (from the release_28 branch):

http://llvm.org/svn/llvm-project/cfe/branches/release_28@114020

Approved by:	rpaulo (mentor)

1 files changed, 4147 insertions, 0 deletions

diff --git a/lib/Serialization/ASTReader.cpp b/lib/Serialization/ASTReader.cpp
new file mode 100644
index 0000000..f07215c
--- /dev/null
+++ b/lib/Serialization/ASTReader.cpp
@@ -0,0 +1,4147 @@
+//===--- ASTReader.cpp - AST File Reader ------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the ASTReader class, which reads AST files.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Serialization/ASTReader.h"
+#include "clang/Serialization/ASTDeserializationListener.h"
+#include "ASTCommon.h"
+#include "clang/Frontend/FrontendDiagnostic.h"
+#include "clang/Frontend/Utils.h"
+#include "clang/Sema/Sema.h"
+#include "clang/Sema/Scope.h"
+#include "clang/AST/ASTConsumer.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclTemplate.h"
+#include "clang/AST/Expr.h"
+#include "clang/AST/ExprCXX.h"
+#include "clang/AST/Type.h"
+#include "clang/AST/TypeLocVisitor.h"
+#include "clang/Lex/MacroInfo.h"
+#include "clang/Lex/PreprocessingRecord.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Lex/HeaderSearch.h"
+#include "clang/Basic/OnDiskHashTable.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Basic/SourceManagerInternals.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/TargetInfo.h"
+#include "clang/Basic/Version.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Bitcode/BitstreamReader.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/System/Path.h"
+#include <algorithm>
+#include <iterator>
+#include <cstdio>
+#include <sys/stat.h>
+using namespace clang;
+using namespace clang::serialization;
+
+//===----------------------------------------------------------------------===//
+// PCH validator implementation
+//===----------------------------------------------------------------------===//
+
+ASTReaderListener::~ASTReaderListener() {}
+
+bool
+PCHValidator::ReadLanguageOptions(const LangOptions &LangOpts) {
+  const LangOptions &PPLangOpts = PP.getLangOptions();
+#define PARSE_LANGOPT_BENIGN(Option)
+#define PARSE_LANGOPT_IMPORTANT(Option, DiagID)                    \
+  if (PPLangOpts.Option != LangOpts.Option) {                      \
+    Reader.Diag(DiagID) << LangOpts.Option << PPLangOpts.Option;   \
+    return true;                                                   \
+  }
+
+  PARSE_LANGOPT_BENIGN(Trigraphs);
+  PARSE_LANGOPT_BENIGN(BCPLComment);
+  PARSE_LANGOPT_BENIGN(DollarIdents);
+  PARSE_LANGOPT_BENIGN(AsmPreprocessor);
+  PARSE_LANGOPT_IMPORTANT(GNUMode, diag::warn_pch_gnu_extensions);
+  PARSE_LANGOPT_IMPORTANT(GNUKeywords, diag::warn_pch_gnu_keywords);
+  PARSE_LANGOPT_BENIGN(ImplicitInt);
+  PARSE_LANGOPT_BENIGN(Digraphs);
+  PARSE_LANGOPT_BENIGN(HexFloats);
+  PARSE_LANGOPT_IMPORTANT(C99, diag::warn_pch_c99);
+  PARSE_LANGOPT_IMPORTANT(Microsoft, diag::warn_pch_microsoft_extensions);
+  PARSE_LANGOPT_IMPORTANT(CPlusPlus, diag::warn_pch_cplusplus);
+  PARSE_LANGOPT_IMPORTANT(CPlusPlus0x, diag::warn_pch_cplusplus0x);
+  PARSE_LANGOPT_BENIGN(CXXOperatorName);
+  PARSE_LANGOPT_IMPORTANT(ObjC1, diag::warn_pch_objective_c);
+  PARSE_LANGOPT_IMPORTANT(ObjC2, diag::warn_pch_objective_c2);
+  PARSE_LANGOPT_IMPORTANT(ObjCNonFragileABI, diag::warn_pch_nonfragile_abi);
+  PARSE_LANGOPT_IMPORTANT(ObjCNonFragileABI2, diag::warn_pch_nonfragile_abi2);
+  PARSE_LANGOPT_IMPORTANT(NoConstantCFStrings, 
+                          diag::warn_pch_no_constant_cfstrings);
+  PARSE_LANGOPT_BENIGN(PascalStrings);
+  PARSE_LANGOPT_BENIGN(WritableStrings);
+  PARSE_LANGOPT_IMPORTANT(LaxVectorConversions,
+                          diag::warn_pch_lax_vector_conversions);
+  PARSE_LANGOPT_IMPORTANT(AltiVec, diag::warn_pch_altivec);
+  PARSE_LANGOPT_IMPORTANT(Exceptions, diag::warn_pch_exceptions);
+  PARSE_LANGOPT_IMPORTANT(SjLjExceptions, diag::warn_pch_sjlj_exceptions);
+  PARSE_LANGOPT_IMPORTANT(NeXTRuntime, diag::warn_pch_objc_runtime);
+  PARSE_LANGOPT_IMPORTANT(Freestanding, diag::warn_pch_freestanding);
+  PARSE_LANGOPT_IMPORTANT(NoBuiltin, diag::warn_pch_builtins);
+  PARSE_LANGOPT_IMPORTANT(ThreadsafeStatics,
+                          diag::warn_pch_thread_safe_statics);
+  PARSE_LANGOPT_IMPORTANT(POSIXThreads, diag::warn_pch_posix_threads);
+  PARSE_LANGOPT_IMPORTANT(Blocks, diag::warn_pch_blocks);
+  PARSE_LANGOPT_BENIGN(EmitAllDecls);
+  PARSE_LANGOPT_IMPORTANT(MathErrno, diag::warn_pch_math_errno);
+  PARSE_LANGOPT_BENIGN(getSignedOverflowBehavior());
+  PARSE_LANGOPT_IMPORTANT(HeinousExtensions,
+                          diag::warn_pch_heinous_extensions);
+  // FIXME: Most of the options below are benign if the macro wasn't
+  // used. Unfortunately, this means that a PCH compiled without
+  // optimization can't be used with optimization turned on, even
+  // though the only thing that changes is whether __OPTIMIZE__ was
+  // defined... but if __OPTIMIZE__ never showed up in the header, it
+  // doesn't matter. We could consider making this some special kind
+  // of check.
+  PARSE_LANGOPT_IMPORTANT(Optimize, diag::warn_pch_optimize);
+  PARSE_LANGOPT_IMPORTANT(OptimizeSize, diag::warn_pch_optimize_size);
+  PARSE_LANGOPT_IMPORTANT(Static, diag::warn_pch_static);
+  PARSE_LANGOPT_IMPORTANT(PICLevel, diag::warn_pch_pic_level);
+  PARSE_LANGOPT_IMPORTANT(GNUInline, diag::warn_pch_gnu_inline);
+  PARSE_LANGOPT_IMPORTANT(NoInline, diag::warn_pch_no_inline);
+  PARSE_LANGOPT_IMPORTANT(AccessControl, diag::warn_pch_access_control);
+  PARSE_LANGOPT_IMPORTANT(CharIsSigned, diag::warn_pch_char_signed);
+  PARSE_LANGOPT_IMPORTANT(ShortWChar, diag::warn_pch_short_wchar);
+  if ((PPLangOpts.getGCMode() != 0) != (LangOpts.getGCMode() != 0)) {
+    Reader.Diag(diag::warn_pch_gc_mode)
+      << LangOpts.getGCMode() << PPLangOpts.getGCMode();
+    return true;
+  }
+  PARSE_LANGOPT_BENIGN(getVisibilityMode());
+  PARSE_LANGOPT_IMPORTANT(getStackProtectorMode(),
+                          diag::warn_pch_stack_protector);
+  PARSE_LANGOPT_BENIGN(InstantiationDepth);
+  PARSE_LANGOPT_IMPORTANT(OpenCL, diag::warn_pch_opencl);
+  PARSE_LANGOPT_BENIGN(CatchUndefined);
+  PARSE_LANGOPT_IMPORTANT(ElideConstructors, diag::warn_pch_elide_constructors);
+  PARSE_LANGOPT_BENIGN(SpellChecking);
+#undef PARSE_LANGOPT_IMPORTANT
+#undef PARSE_LANGOPT_BENIGN
+
+  return false;
+}
+
+bool PCHValidator::ReadTargetTriple(llvm::StringRef Triple) {
+  if (Triple == PP.getTargetInfo().getTriple().str())
+    return false;
+
+  Reader.Diag(diag::warn_pch_target_triple)
+    << Triple << PP.getTargetInfo().getTriple().str();
+  return true;
+}
+
+struct EmptyStringRef {
+  bool operator ()(llvm::StringRef r) const { return r.empty(); }
+};
+struct EmptyBlock {
+  bool operator ()(const PCHPredefinesBlock &r) const { return r.Data.empty(); }
+};
+
+static bool EqualConcatenations(llvm::SmallVector<llvm::StringRef, 2> L,
+                                PCHPredefinesBlocks R) {
+  // First, sum up the lengths.
+  unsigned LL = 0, RL = 0;
+  for (unsigned I = 0, N = L.size(); I != N; ++I) {
+    LL += L[I].size();
+  }
+  for (unsigned I = 0, N = R.size(); I != N; ++I) {
+    RL += R[I].Data.size();
+  }
+  if (LL != RL)
+    return false;
+  if (LL == 0 && RL == 0)
+    return true;
+
+  // Kick out empty parts, they confuse the algorithm below.
+  L.erase(std::remove_if(L.begin(), L.end(), EmptyStringRef()), L.end());
+  R.erase(std::remove_if(R.begin(), R.end(), EmptyBlock()), R.end());
+
+  // Do it the hard way. At this point, both vectors must be non-empty.
+  llvm::StringRef LR = L[0], RR = R[0].Data;
+  unsigned LI = 0, RI = 0, LN = L.size(), RN = R.size();
+  (void) RN;
+  for (;;) {
+    // Compare the current pieces.
+    if (LR.size() == RR.size()) {
+      // If they're the same length, it's pretty easy.
+      if (LR != RR)
+        return false;
+      // Both pieces are done, advance.
+      ++LI;
+      ++RI;
+      // If either string is done, they're both done, since they're the same
+      // length.
+      if (LI == LN) {
+        assert(RI == RN && "Strings not the same length after all?");
+        return true;
+      }
+      LR = L[LI];
+      RR = R[RI].Data;
+    } else if (LR.size() < RR.size()) {
+      // Right piece is longer.
+      if (!RR.startswith(LR))
+        return false;
+      ++LI;
+      assert(LI != LN && "Strings not the same length after all?");
+      RR = RR.substr(LR.size());
+      LR = L[LI];
+    } else {
+      // Left piece is longer.
+      if (!LR.startswith(RR))
+        return false;
+      ++RI;
+      assert(RI != RN && "Strings not the same length after all?");
+      LR = LR.substr(RR.size());
+      RR = R[RI].Data;
+    }
+  }
+}
+
+static std::pair<FileID, llvm::StringRef::size_type>
+FindMacro(const PCHPredefinesBlocks &Buffers, llvm::StringRef MacroDef) {
+  std::pair<FileID, llvm::StringRef::size_type> Res;
+  for (unsigned I = 0, N = Buffers.size(); I != N; ++I) {
+    Res.second = Buffers[I].Data.find(MacroDef);
+    if (Res.second != llvm::StringRef::npos) {
+      Res.first = Buffers[I].BufferID;
+      break;
+    }
+  }
+  return Res;
+}
+
+bool PCHValidator::ReadPredefinesBuffer(const PCHPredefinesBlocks &Buffers,
+                                        llvm::StringRef OriginalFileName,
+                                        std::string &SuggestedPredefines) {
+  // We are in the context of an implicit include, so the predefines buffer will
+  // have a #include entry for the PCH file itself (as normalized by the
+  // preprocessor initialization). Find it and skip over it in the checking
+  // below.
+  llvm::SmallString<256> PCHInclude;
+  PCHInclude += "#include \"";
+  PCHInclude += NormalizeDashIncludePath(OriginalFileName);
+  PCHInclude += "\"\n";
+  std::pair<llvm::StringRef,llvm::StringRef> Split =
+    llvm::StringRef(PP.getPredefines()).split(PCHInclude.str());
+  llvm::StringRef Left =  Split.first, Right = Split.second;
+  if (Left == PP.getPredefines()) {
+    Error("Missing PCH include entry!");
+    return true;
+  }
+
+  // If the concatenation of all the PCH buffers is equal to the adjusted
+  // command line, we're done.
+  llvm::SmallVector<llvm::StringRef, 2> CommandLine;
+  CommandLine.push_back(Left);
+  CommandLine.push_back(Right);
+  if (EqualConcatenations(CommandLine, Buffers))
+    return false;
+
+  SourceManager &SourceMgr = PP.getSourceManager();
+
+  // The predefines buffers are different. Determine what the differences are,
+  // and whether they require us to reject the PCH file.
+  llvm::SmallVector<llvm::StringRef, 8> PCHLines;
+  for (unsigned I = 0, N = Buffers.size(); I != N; ++I)
+    Buffers[I].Data.split(PCHLines, "\n", /*MaxSplit=*/-1, /*KeepEmpty=*/false);
+
+  llvm::SmallVector<llvm::StringRef, 8> CmdLineLines;
+  Left.split(CmdLineLines, "\n", /*MaxSplit=*/-1, /*KeepEmpty=*/false);
+  Right.split(CmdLineLines, "\n", /*MaxSplit=*/-1, /*KeepEmpty=*/false);
+
+  // Sort both sets of predefined buffer lines, since we allow some extra
+  // definitions and they may appear at any point in the output.
+  std::sort(CmdLineLines.begin(), CmdLineLines.end());
+  std::sort(PCHLines.begin(), PCHLines.end());
+
+  // Determine which predefines that were used to build the PCH file are missing
+  // from the command line.
+  std::vector<llvm::StringRef> MissingPredefines;
+  std::set_difference(PCHLines.begin(), PCHLines.end(),
+                      CmdLineLines.begin(), CmdLineLines.end(),
+                      std::back_inserter(MissingPredefines));
+
+  bool MissingDefines = false;
+  bool ConflictingDefines = false;
+  for (unsigned I = 0, N = MissingPredefines.size(); I != N; ++I) {
+    llvm::StringRef Missing = MissingPredefines[I];
+    if (!Missing.startswith("#define ")) {
+      Reader.Diag(diag::warn_pch_compiler_options_mismatch);
+      return true;
+    }
+
+    // This is a macro definition. Determine the name of the macro we're
+    // defining.
+    std::string::size_type StartOfMacroName = strlen("#define ");
+    std::string::size_type EndOfMacroName
+      = Missing.find_first_of("( \n\r", StartOfMacroName);
+    assert(EndOfMacroName != std::string::npos &&
+           "Couldn't find the end of the macro name");
+    llvm::StringRef MacroName = Missing.slice(StartOfMacroName, EndOfMacroName);
+
+    // Determine whether this macro was given a different definition on the
+    // command line.
+    std::string MacroDefStart = "#define " + MacroName.str();
+    std::string::size_type MacroDefLen = MacroDefStart.size();
+    llvm::SmallVector<llvm::StringRef, 8>::iterator ConflictPos
+      = std::lower_bound(CmdLineLines.begin(), CmdLineLines.end(),
+                         MacroDefStart);
+    for (; ConflictPos != CmdLineLines.end(); ++ConflictPos) {
+      if (!ConflictPos->startswith(MacroDefStart)) {
+        // Different macro; we're done.
+        ConflictPos = CmdLineLines.end();
+        break;
+      }
+
+      assert(ConflictPos->size() > MacroDefLen &&
+             "Invalid #define in predefines buffer?");
+      if ((*ConflictPos)[MacroDefLen] != ' ' &&
+          (*ConflictPos)[MacroDefLen] != '(')
+        continue; // Longer macro name; keep trying.
+
+      // We found a conflicting macro definition.
+      break;
+    }
+
+    if (ConflictPos != CmdLineLines.end()) {
+      Reader.Diag(diag::warn_cmdline_conflicting_macro_def)
+          << MacroName;
+
+      // Show the definition of this macro within the PCH file.
+      std::pair<FileID, llvm::StringRef::size_type> MacroLoc =
+          FindMacro(Buffers, Missing);
+      assert(MacroLoc.second!=llvm::StringRef::npos && "Unable to find macro!");
+      SourceLocation PCHMissingLoc =
+          SourceMgr.getLocForStartOfFile(MacroLoc.first)
+            .getFileLocWithOffset(MacroLoc.second);
+      Reader.Diag(PCHMissingLoc, diag::note_pch_macro_defined_as) << MacroName;
+
+      ConflictingDefines = true;
+      continue;
+    }
+
+    // If the macro doesn't conflict, then we'll just pick up the macro
+    // definition from the PCH file. Warn the user that they made a mistake.
+    if (ConflictingDefines)
+      continue; // Don't complain if there are already conflicting defs
+
+    if (!MissingDefines) {
+      Reader.Diag(diag::warn_cmdline_missing_macro_defs);
+      MissingDefines = true;
+    }
+
+    // Show the definition of this macro within the PCH file.
+    std::pair<FileID, llvm::StringRef::size_type> MacroLoc =
+        FindMacro(Buffers, Missing);
+    assert(MacroLoc.second!=llvm::StringRef::npos && "Unable to find macro!");
+    SourceLocation PCHMissingLoc =
+        SourceMgr.getLocForStartOfFile(MacroLoc.first)
+          .getFileLocWithOffset(MacroLoc.second);
+    Reader.Diag(PCHMissingLoc, diag::note_using_macro_def_from_pch);
+  }
+
+  if (ConflictingDefines)
+    return true;
+
+  // Determine what predefines were introduced based on command-line
+  // parameters that were not present when building the PCH
+  // file. Extra #defines are okay, so long as the identifiers being
+  // defined were not used within the precompiled header.
+  std::vector<llvm::StringRef> ExtraPredefines;
+  std::set_difference(CmdLineLines.begin(), CmdLineLines.end(),
+                      PCHLines.begin(), PCHLines.end(),
+                      std::back_inserter(ExtraPredefines));
+  for (unsigned I = 0, N = ExtraPredefines.size(); I != N; ++I) {
+    llvm::StringRef &Extra = ExtraPredefines[I];
+    if (!Extra.startswith("#define ")) {
+      Reader.Diag(diag::warn_pch_compiler_options_mismatch);
+      return true;
+    }
+
+    // This is an extra macro definition. Determine the name of the
+    // macro we're defining.
+    std::string::size_type StartOfMacroName = strlen("#define ");
+    std::string::size_type EndOfMacroName
+      = Extra.find_first_of("( \n\r", StartOfMacroName);
+    assert(EndOfMacroName != std::string::npos &&
+           "Couldn't find the end of the macro name");
+    llvm::StringRef MacroName = Extra.slice(StartOfMacroName, EndOfMacroName);
+
+    // Check whether this name was used somewhere in the PCH file. If
+    // so, defining it as a macro could change behavior, so we reject
+    // the PCH file.
+    if (IdentifierInfo *II = Reader.get(MacroName)) {
+      Reader.Diag(diag::warn_macro_name_used_in_pch) << II;
+      return true;
+    }
+
+    // Add this definition to the suggested predefines buffer.
+    SuggestedPredefines += Extra;
+    SuggestedPredefines += '\n';
+  }
+
+  // If we get here, it's because the predefines buffer had compatible
+  // contents. Accept the PCH file.
+  return false;
+}
+
+void PCHValidator::ReadHeaderFileInfo(const HeaderFileInfo &HFI,
+                                      unsigned ID) {
+  PP.getHeaderSearchInfo().setHeaderFileInfoForUID(HFI, ID);
+  ++NumHeaderInfos;
+}
+
+void PCHValidator::ReadCounter(unsigned Value) {
+  PP.setCounterValue(Value);
+}
+
+//===----------------------------------------------------------------------===//
+// AST reader implementation
+//===----------------------------------------------------------------------===//
+
+void
+ASTReader::setDeserializationListener(ASTDeserializationListener *Listener) {
+  DeserializationListener = Listener;
+  if (DeserializationListener)
+    DeserializationListener->SetReader(this);
+}
+
+
+namespace {
+class ASTSelectorLookupTrait {
+  ASTReader &Reader;
+
+public:
+  struct data_type {
+    SelectorID ID;
+    ObjCMethodList Instance, Factory;
+  };
+
+  typedef Selector external_key_type;
+  typedef external_key_type internal_key_type;
+
+  explicit ASTSelectorLookupTrait(ASTReader &Reader) : Reader(Reader) { }
+
+  static bool EqualKey(const internal_key_type& a,
+                       const internal_key_type& b) {
+    return a == b;
+  }
+
+  static unsigned ComputeHash(Selector Sel) {
+    return serialization::ComputeHash(Sel);
+  }
+
+  // This hopefully will just get inlined and removed by the optimizer.
+  static const internal_key_type&
+  GetInternalKey(const external_key_type& x) { return x; }
+
+  static std::pair<unsigned, unsigned>
+  ReadKeyDataLength(const unsigned char*& d) {
+    using namespace clang::io;
+    unsigned KeyLen = ReadUnalignedLE16(d);
+    unsigned DataLen = ReadUnalignedLE16(d);
+    return std::make_pair(KeyLen, DataLen);
+  }
+
+  internal_key_type ReadKey(const unsigned char* d, unsigned) {
+    using namespace clang::io;
+    SelectorTable &SelTable = Reader.getContext()->Selectors;
+    unsigned N = ReadUnalignedLE16(d);
+    IdentifierInfo *FirstII
+      = Reader.DecodeIdentifierInfo(ReadUnalignedLE32(d));
+    if (N == 0)
+      return SelTable.getNullarySelector(FirstII);
+    else if (N == 1)
+      return SelTable.getUnarySelector(FirstII);
+
+    llvm::SmallVector<IdentifierInfo *, 16> Args;
+    Args.push_back(FirstII);
+    for (unsigned I = 1; I != N; ++I)
+      Args.push_back(Reader.DecodeIdentifierInfo(ReadUnalignedLE32(d)));
+
+    return SelTable.getSelector(N, Args.data());
+  }
+
+  data_type ReadData(Selector, const unsigned char* d, unsigned DataLen) {
+    using namespace clang::io;
+
+    data_type Result;
+
+    Result.ID = ReadUnalignedLE32(d);
+    unsigned NumInstanceMethods = ReadUnalignedLE16(d);
+    unsigned NumFactoryMethods = ReadUnalignedLE16(d);
+
+    // Load instance methods
+    ObjCMethodList *Prev = 0;
+    for (unsigned I = 0; I != NumInstanceMethods; ++I) {
+      ObjCMethodDecl *Method
+        = cast<ObjCMethodDecl>(Reader.GetDecl(ReadUnalignedLE32(d)));
+      if (!Result.Instance.Method) {
+        // This is the first method, which is the easy case.
+        Result.Instance.Method = Method;
+        Prev = &Result.Instance;
+        continue;
+      }
+
+      ObjCMethodList *Mem =
+        Reader.getSema()->BumpAlloc.Allocate<ObjCMethodList>();
+      Prev->Next = new (Mem) ObjCMethodList(Method, 0);
+      Prev = Prev->Next;
+    }
+
+    // Load factory methods
+    Prev = 0;
+    for (unsigned I = 0; I != NumFactoryMethods; ++I) {
+      ObjCMethodDecl *Method
+        = cast<ObjCMethodDecl>(Reader.GetDecl(ReadUnalignedLE32(d)));
+      if (!Result.Factory.Method) {
+        // This is the first method, which is the easy case.
+        Result.Factory.Method = Method;
+        Prev = &Result.Factory;
+        continue;
+      }
+
+      ObjCMethodList *Mem =
+        Reader.getSema()->BumpAlloc.Allocate<ObjCMethodList>();
+      Prev->Next = new (Mem) ObjCMethodList(Method, 0);
+      Prev = Prev->Next;
+    }
+
+    return Result;
+  }
+};
+
+} // end anonymous namespace
+
+/// \brief The on-disk hash table used for the global method pool.
+typedef OnDiskChainedHashTable<ASTSelectorLookupTrait>
+  ASTSelectorLookupTable;
+
+namespace {
+class ASTIdentifierLookupTrait {
+  ASTReader &Reader;
+  llvm::BitstreamCursor &Stream;
+
+  // If we know the IdentifierInfo in advance, it is here and we will
+  // not build a new one. Used when deserializing information about an
+  // identifier that was constructed before the AST file was read.
+  IdentifierInfo *KnownII;
+
+public:
+  typedef IdentifierInfo * data_type;
+
+  typedef const std::pair<const char*, unsigned> external_key_type;
+
+  typedef external_key_type internal_key_type;
+
+  ASTIdentifierLookupTrait(ASTReader &Reader, llvm::BitstreamCursor &Stream,
+                           IdentifierInfo *II = 0)
+    : Reader(Reader), Stream(Stream), KnownII(II) { }
+
+  static bool EqualKey(const internal_key_type& a,
+                       const internal_key_type& b) {
+    return (a.second == b.second) ? memcmp(a.first, b.first, a.second) == 0
+                                  : false;
+  }
+
+  static unsigned ComputeHash(const internal_key_type& a) {
+    return llvm::HashString(llvm::StringRef(a.first, a.second));
+  }
+
+  // This hopefully will just get inlined and removed by the optimizer.
+  static const internal_key_type&
+  GetInternalKey(const external_key_type& x) { return x; }
+
+  static std::pair<unsigned, unsigned>
+  ReadKeyDataLength(const unsigned char*& d) {
+    using namespace clang::io;
+    unsigned DataLen = ReadUnalignedLE16(d);
+    unsigned KeyLen = ReadUnalignedLE16(d);
+    return std::make_pair(KeyLen, DataLen);
+  }
+
+  static std::pair<const char*, unsigned>
+  ReadKey(const unsigned char* d, unsigned n) {
+    assert(n >= 2 && d[n-1] == '\0');
+    return std::make_pair((const char*) d, n-1);
+  }
+
+  IdentifierInfo *ReadData(const internal_key_type& k,
+                           const unsigned char* d,
+                           unsigned DataLen) {
+    using namespace clang::io;
+    IdentID ID = ReadUnalignedLE32(d);
+    bool IsInteresting = ID & 0x01;
+
+    // Wipe out the "is interesting" bit.
+    ID = ID >> 1;
+
+    if (!IsInteresting) {
+      // For uninteresting identifiers, just build the IdentifierInfo
+      // and associate it with the persistent ID.
+      IdentifierInfo *II = KnownII;
+      if (!II)
+        II = &Reader.getIdentifierTable().getOwn(k.first, k.first + k.second);
+      Reader.SetIdentifierInfo(ID, II);
+      II->setIsFromAST();
+      return II;
+    }
+
+    unsigned Bits = ReadUnalignedLE16(d);
+    bool CPlusPlusOperatorKeyword = Bits & 0x01;
+    Bits >>= 1;
+    bool HasRevertedTokenIDToIdentifier = Bits & 0x01;
+    Bits >>= 1;
+    bool Poisoned = Bits & 0x01;
+    Bits >>= 1;
+    bool ExtensionToken = Bits & 0x01;
+    Bits >>= 1;
+    bool hasMacroDefinition = Bits & 0x01;
+    Bits >>= 1;
+    unsigned ObjCOrBuiltinID = Bits & 0x3FF;
+    Bits >>= 10;
+
+    assert(Bits == 0 && "Extra bits in the identifier?");
+    DataLen -= 6;
+
+    // Build the IdentifierInfo itself and link the identifier ID with
+    // the new IdentifierInfo.
+    IdentifierInfo *II = KnownII;
+    if (!II)
+      II = &Reader.getIdentifierTable().getOwn(k.first, k.first + k.second);
+    Reader.SetIdentifierInfo(ID, II);
+
+    // Set or check the various bits in the IdentifierInfo structure.
+    // Token IDs are read-only.
+    if (HasRevertedTokenIDToIdentifier)
+      II->RevertTokenIDToIdentifier();
+    II->setObjCOrBuiltinID(ObjCOrBuiltinID);
+    assert(II->isExtensionToken() == ExtensionToken &&
+           "Incorrect extension token flag");
+    (void)ExtensionToken;
+    II->setIsPoisoned(Poisoned);
+    assert(II->isCPlusPlusOperatorKeyword() == CPlusPlusOperatorKeyword &&
+           "Incorrect C++ operator keyword flag");
+    (void)CPlusPlusOperatorKeyword;
+
+    // If this identifier is a macro, deserialize the macro
+    // definition.
+    if (hasMacroDefinition) {
+      uint32_t Offset = ReadUnalignedLE32(d);
+      Reader.ReadMacroRecord(Stream, Offset);
+      DataLen -= 4;
+    }
+
+    // Read all of the declarations visible at global scope with this
+    // name.
+    if (Reader.getContext() == 0) return II;
+    if (DataLen > 0) {
+      llvm::SmallVector<uint32_t, 4> DeclIDs;
+      for (; DataLen > 0; DataLen -= 4)
+        DeclIDs.push_back(ReadUnalignedLE32(d));
+      Reader.SetGloballyVisibleDecls(II, DeclIDs);
+    }
+
+    II->setIsFromAST();
+    return II;
+  }
+};
+
+} // end anonymous namespace
+
+/// \brief The on-disk hash table used to contain information about
+/// all of the identifiers in the program.
+typedef OnDiskChainedHashTable<ASTIdentifierLookupTrait>
+  ASTIdentifierLookupTable;
+
+namespace {
+class ASTDeclContextNameLookupTrait {
+  ASTReader &Reader;
+
+public:
+  /// \brief Pair of begin/end iterators for DeclIDs.
+  typedef std::pair<DeclID *, DeclID *> data_type;
+
+  /// \brief Special internal key for declaration names.
+  /// The hash table creates keys for comparison; we do not create
+  /// a DeclarationName for the internal key to avoid deserializing types.
+  struct DeclNameKey {
+    DeclarationName::NameKind Kind;
+    uint64_t Data;
+    DeclNameKey() : Kind((DeclarationName::NameKind)0), Data(0) { }
+  };
+
+  typedef DeclarationName external_key_type;
+  typedef DeclNameKey internal_key_type;
+
+  explicit ASTDeclContextNameLookupTrait(ASTReader &Reader) : Reader(Reader) { }
+
+  static bool EqualKey(const internal_key_type& a,
+                       const internal_key_type& b) {
+    return a.Kind == b.Kind && a.Data == b.Data;
+  }
+
+  unsigned ComputeHash(const DeclNameKey &Key) const {
+    llvm::FoldingSetNodeID ID;
+    ID.AddInteger(Key.Kind);
+
+    switch (Key.Kind) {
+    case DeclarationName::Identifier:
+    case DeclarationName::CXXLiteralOperatorName:
+      ID.AddString(((IdentifierInfo*)Key.Data)->getName());
+      break;
+    case DeclarationName::ObjCZeroArgSelector:
+    case DeclarationName::ObjCOneArgSelector:
+    case DeclarationName::ObjCMultiArgSelector:
+      ID.AddInteger(serialization::ComputeHash(Selector(Key.Data)));
+      break;
+    case DeclarationName::CXXConstructorName:
+    case DeclarationName::CXXDestructorName:
+    case DeclarationName::CXXConversionFunctionName:
+      ID.AddInteger((TypeID)Key.Data);
+      break;
+    case DeclarationName::CXXOperatorName:
+      ID.AddInteger((OverloadedOperatorKind)Key.Data);
+      break;
+    case DeclarationName::CXXUsingDirective:
+      break;
+    }
+
+    return ID.ComputeHash();
+  }
+
+  internal_key_type GetInternalKey(const external_key_type& Name) const {
+    DeclNameKey Key;
+    Key.Kind = Name.getNameKind();
+    switch (Name.getNameKind()) {
+    case DeclarationName::Identifier:
+      Key.Data = (uint64_t)Name.getAsIdentifierInfo();
+      break;
+    case DeclarationName::ObjCZeroArgSelector:
+    case DeclarationName::ObjCOneArgSelector:
+    case DeclarationName::ObjCMultiArgSelector:
+      Key.Data = (uint64_t)Name.getObjCSelector().getAsOpaquePtr();
+      break;
+    case DeclarationName::CXXConstructorName:
+    case DeclarationName::CXXDestructorName:
+    case DeclarationName::CXXConversionFunctionName:
+      Key.Data = Reader.GetTypeID(Name.getCXXNameType());
+      break;
+    case DeclarationName::CXXOperatorName:
+      Key.Data = Name.getCXXOverloadedOperator();
+      break;
+    case DeclarationName::CXXLiteralOperatorName:
+      Key.Data = (uint64_t)Name.getCXXLiteralIdentifier();
+      break;
+    case DeclarationName::CXXUsingDirective:
+      break;
+    }
+    
+    return Key;
+  }
+
+  external_key_type GetExternalKey(const internal_key_type& Key) const {
+    ASTContext *Context = Reader.getContext();
+    switch (Key.Kind) {
+    case DeclarationName::Identifier:
+      return DeclarationName((IdentifierInfo*)Key.Data);
+
+    case DeclarationName::ObjCZeroArgSelector:
+    case DeclarationName::ObjCOneArgSelector:
+    case DeclarationName::ObjCMultiArgSelector:
+      return DeclarationName(Selector(Key.Data));
+
+    case DeclarationName::CXXConstructorName:
+      return Context->DeclarationNames.getCXXConstructorName(
+                           Context->getCanonicalType(Reader.GetType(Key.Data)));
+
+    case DeclarationName::CXXDestructorName:
+      return Context->DeclarationNames.getCXXDestructorName(
+                           Context->getCanonicalType(Reader.GetType(Key.Data)));
+
+    case DeclarationName::CXXConversionFunctionName:
+      return Context->DeclarationNames.getCXXConversionFunctionName(
+                           Context->getCanonicalType(Reader.GetType(Key.Data)));
+
+    case DeclarationName::CXXOperatorName:
+      return Context->DeclarationNames.getCXXOperatorName(
+                                         (OverloadedOperatorKind)Key.Data);
+
+    case DeclarationName::CXXLiteralOperatorName:
+      return Context->DeclarationNames.getCXXLiteralOperatorName(
+                                                     (IdentifierInfo*)Key.Data);
+
+    case DeclarationName::CXXUsingDirective:
+      return DeclarationName::getUsingDirectiveName();
+    }
+
+    llvm_unreachable("Invalid Name Kind ?");
+  }
+
+  static std::pair<unsigned, unsigned>
+  ReadKeyDataLength(const unsigned char*& d) {
+    using namespace clang::io;
+    unsigned KeyLen = ReadUnalignedLE16(d);
+    unsigned DataLen = ReadUnalignedLE16(d);
+    return std::make_pair(KeyLen, DataLen);
+  }
+
+  internal_key_type ReadKey(const unsigned char* d, unsigned) {
+    using namespace clang::io;
+
+    DeclNameKey Key;
+    Key.Kind = (DeclarationName::NameKind)*d++;
+    switch (Key.Kind) {
+    case DeclarationName::Identifier:
+      Key.Data = (uint64_t)Reader.DecodeIdentifierInfo(ReadUnalignedLE32(d));
+      break;
+    case DeclarationName::ObjCZeroArgSelector:
+    case DeclarationName::ObjCOneArgSelector:
+    case DeclarationName::ObjCMultiArgSelector:
+      Key.Data = 
+         (uint64_t)Reader.DecodeSelector(ReadUnalignedLE32(d)).getAsOpaquePtr();
+      break;
+    case DeclarationName::CXXConstructorName:
+    case DeclarationName::CXXDestructorName:
+    case DeclarationName::CXXConversionFunctionName:
+      Key.Data = ReadUnalignedLE32(d); // TypeID
+      break;
+    case DeclarationName::CXXOperatorName:
+      Key.Data = *d++; // OverloadedOperatorKind
+      break;
+    case DeclarationName::CXXLiteralOperatorName:
+      Key.Data = (uint64_t)Reader.DecodeIdentifierInfo(ReadUnalignedLE32(d));
+      break;
+    case DeclarationName::CXXUsingDirective:
+      break;
+    }
+    
+    return Key;
+  }
+
+  data_type ReadData(internal_key_type, const unsigned char* d,
+                     unsigned DataLen) {
+    using namespace clang::io;
+    unsigned NumDecls = ReadUnalignedLE16(d);
+    DeclID *Start = (DeclID *)d;
+    return std::make_pair(Start, Start + NumDecls);
+  }
+};
+
+} // end anonymous namespace
+
+/// \brief The on-disk hash table used for the DeclContext's Name lookup table.
+typedef OnDiskChainedHashTable<ASTDeclContextNameLookupTrait>
+  ASTDeclContextNameLookupTable;
+
+bool ASTReader::ReadDeclContextStorage(llvm::BitstreamCursor &Cursor,
+                                   const std::pair<uint64_t, uint64_t> &Offsets,
+                                       DeclContextInfo &Info) {
+  SavedStreamPosition SavedPosition(Cursor);
+  // First the lexical decls.
+  if (Offsets.first != 0) {
+    Cursor.JumpToBit(Offsets.first);
+
+    RecordData Record;
+    const char *Blob;
+    unsigned BlobLen;
+    unsigned Code = Cursor.ReadCode();
+    unsigned RecCode = Cursor.ReadRecord(Code, Record, &Blob, &BlobLen);
+    if (RecCode != DECL_CONTEXT_LEXICAL) {
+      Error("Expected lexical block");
+      return true;
+    }
+
+    Info.LexicalDecls = reinterpret_cast<const DeclID*>(Blob);
+    Info.NumLexicalDecls = BlobLen / sizeof(DeclID);
+  } else {
+    Info.LexicalDecls = 0;
+    Info.NumLexicalDecls = 0;
+  }
+
+  // Now the lookup table.
+  if (Offsets.second != 0) {
+    Cursor.JumpToBit(Offsets.second);
+
+    RecordData Record;
+    const char *Blob;
+    unsigned BlobLen;
+    unsigned Code = Cursor.ReadCode();
+    unsigned RecCode = Cursor.ReadRecord(Code, Record, &Blob, &BlobLen);
+    if (RecCode != DECL_CONTEXT_VISIBLE) {
+      Error("Expected visible lookup table block");
+      return true;
+    }
+    Info.NameLookupTableData
+      = ASTDeclContextNameLookupTable::Create(
+                    (const unsigned char *)Blob + Record[0],
+                    (const unsigned char *)Blob,
+                    ASTDeclContextNameLookupTrait(*this));
+  } else {
+    Info.NameLookupTableData = 0;
+  }
+
+  return false;
+}
+
+void ASTReader::Error(const char *Msg) {
+  Diag(diag::err_fe_pch_malformed) << Msg;
+}
+
+/// \brief Tell the AST listener about the predefines buffers in the chain.
+bool ASTReader::CheckPredefinesBuffers() {
+  if (Listener)
+    return Listener->ReadPredefinesBuffer(PCHPredefinesBuffers,
+                                          ActualOriginalFileName,
+                                          SuggestedPredefines);
+  return false;
+}
+
+//===----------------------------------------------------------------------===//
+// Source Manager Deserialization
+//===----------------------------------------------------------------------===//
+
+/// \brief Read the line table in the source manager block.
+/// \returns true if ther was an error.
+bool ASTReader::ParseLineTable(llvm::SmallVectorImpl<uint64_t> &Record) {
+  unsigned Idx = 0;
+  LineTableInfo &LineTable = SourceMgr.getLineTable();
+
+  // Parse the file names
+  std::map<int, int> FileIDs;
+  for (int I = 0, N = Record[Idx++]; I != N; ++I) {
+    // Extract the file name
+    unsigned FilenameLen = Record[Idx++];
+    std::string Filename(&Record[Idx], &Record[Idx] + FilenameLen);
+    Idx += FilenameLen;
+    MaybeAddSystemRootToFilename(Filename);
+    FileIDs[I] = LineTable.getLineTableFilenameID(Filename.c_str(),
+                                                  Filename.size());
+  }
+
+  // Parse the line entries
+  std::vector<LineEntry> Entries;
+  while (Idx < Record.size()) {
+    int FID = Record[Idx++];
+
+    // Extract the line entries
+    unsigned NumEntries = Record[Idx++];
+    assert(NumEntries && "Numentries is 00000");
+    Entries.clear();
+    Entries.reserve(NumEntries);
+    for (unsigned I = 0; I != NumEntries; ++I) {
+      unsigned FileOffset = Record[Idx++];
+      unsigned LineNo = Record[Idx++];
+      int FilenameID = FileIDs[Record[Idx++]];
+      SrcMgr::CharacteristicKind FileKind
+        = (SrcMgr::CharacteristicKind)Record[Idx++];
+      unsigned IncludeOffset = Record[Idx++];
+      Entries.push_back(LineEntry::get(FileOffset, LineNo, FilenameID,
+                                       FileKind, IncludeOffset));
+    }
+    LineTable.AddEntry(FID, Entries);
+  }
+
+  return false;
+}
+
+namespace {
+
+class ASTStatData {
+public:
+  const bool hasStat;
+  const ino_t ino;
+  const dev_t dev;
+  const mode_t mode;
+  const time_t mtime;
+  const off_t size;
+
+  ASTStatData(ino_t i, dev_t d, mode_t mo, time_t m, off_t s)
+  : hasStat(true), ino(i), dev(d), mode(mo), mtime(m), size(s) {}
+
+  ASTStatData()
+    : hasStat(false), ino(0), dev(0), mode(0), mtime(0), size(0) {}
+};
+
+class ASTStatLookupTrait {
+ public:
+  typedef const char *external_key_type;
+  typedef const char *internal_key_type;
+
+  typedef ASTStatData data_type;
+
+  static unsigned ComputeHash(const char *path) {
+    return llvm::HashString(path);
+  }
+
+  static internal_key_type GetInternalKey(const char *path) { return path; }
+
+  static bool EqualKey(internal_key_type a, internal_key_type b) {
+    return strcmp(a, b) == 0;
+  }
+
+  static std::pair<unsigned, unsigned>
+  ReadKeyDataLength(const unsigned char*& d) {
+    unsigned KeyLen = (unsigned) clang::io::ReadUnalignedLE16(d);
+    unsigned DataLen = (unsigned) *d++;
+    return std::make_pair(KeyLen + 1, DataLen);
+  }
+
+  static internal_key_type ReadKey(const unsigned char *d, unsigned) {
+    return (const char *)d;
+  }
+
+  static data_type ReadData(const internal_key_type, const unsigned char *d,
+                            unsigned /*DataLen*/) {
+    using namespace clang::io;
+
+    if (*d++ == 1)
+      return data_type();
+
+    ino_t ino = (ino_t) ReadUnalignedLE32(d);
+    dev_t dev = (dev_t) ReadUnalignedLE32(d);
+    mode_t mode = (mode_t) ReadUnalignedLE16(d);
+    time_t mtime = (time_t) ReadUnalignedLE64(d);
+    off_t size = (off_t) ReadUnalignedLE64(d);
+    return data_type(ino, dev, mode, mtime, size);
+  }
+};
+
+/// \brief stat() cache for precompiled headers.
+///
+/// This cache is very similar to the stat cache used by pretokenized
+/// headers.
+class ASTStatCache : public StatSysCallCache {
+  typedef OnDiskChainedHashTable<ASTStatLookupTrait> CacheTy;
+  CacheTy *Cache;
+
+  unsigned &NumStatHits, &NumStatMisses;
+public:
+  ASTStatCache(const unsigned char *Buckets,
+               const unsigned char *Base,
+               unsigned &NumStatHits,
+               unsigned &NumStatMisses)
+    : Cache(0), NumStatHits(NumStatHits), NumStatMisses(NumStatMisses) {
+    Cache = CacheTy::Create(Buckets, Base);
+  }
+
+  ~ASTStatCache() { delete Cache; }
+
+  int stat(const char *path, struct stat *buf) {
+    // Do the lookup for the file's data in the AST file.
+    CacheTy::iterator I = Cache->find(path);
+
+    // If we don't get a hit in the AST file just forward to 'stat'.
+    if (I == Cache->end()) {
+      ++NumStatMisses;
+      return StatSysCallCache::stat(path, buf);
+    }
+
+    ++NumStatHits;
+    ASTStatData Data = *I;
+
+    if (!Data.hasStat)
+      return 1;
+
+    buf->st_ino = Data.ino;
+    buf->st_dev = Data.dev;
+    buf->st_mtime = Data.mtime;
+    buf->st_mode = Data.mode;
+    buf->st_size = Data.size;
+    return 0;
+  }
+};
+} // end anonymous namespace
+
+
+/// \brief Read a source manager block
+ASTReader::ASTReadResult ASTReader::ReadSourceManagerBlock(PerFileData &F) {
+  using namespace SrcMgr;
+
+  llvm::BitstreamCursor &SLocEntryCursor = F.SLocEntryCursor;
+
+  // Set the source-location entry cursor to the current position in
+  // the stream. This cursor will be used to read the contents of the
+  // source manager block initially, and then lazily read
+  // source-location entries as needed.
+  SLocEntryCursor = F.Stream;
+
+  // The stream itself is going to skip over the source manager block.
+  if (F.Stream.SkipBlock()) {
+    Error("malformed block record in AST file");
+    return Failure;
+  }
+
+  // Enter the source manager block.
+  if (SLocEntryCursor.EnterSubBlock(SOURCE_MANAGER_BLOCK_ID)) {
+    Error("malformed source manager block record in AST file");
+    return Failure;
+  }
+
+  RecordData Record;
+  while (true) {
+    unsigned Code = SLocEntryCursor.ReadCode();
+    if (Code == llvm::bitc::END_BLOCK) {
+      if (SLocEntryCursor.ReadBlockEnd()) {
+        Error("error at end of Source Manager block in AST file");
+        return Failure;
+      }
+      return Success;
+    }
+
+    if (Code == llvm::bitc::ENTER_SUBBLOCK) {
+      // No known subblocks, always skip them.
+      SLocEntryCursor.ReadSubBlockID();
+      if (SLocEntryCursor.SkipBlock()) {
+        Error("malformed block record in AST file");
+        return Failure;
+      }
+      continue;
+    }
+
+    if (Code == llvm::bitc::DEFINE_ABBREV) {
+      SLocEntryCursor.ReadAbbrevRecord();
+      continue;
+    }
+
+    // Read a record.
+    const char *BlobStart;
+    unsigned BlobLen;
+    Record.clear();
+    switch (SLocEntryCursor.ReadRecord(Code, Record, &BlobStart, &BlobLen)) {
+    default:  // Default behavior: ignore.
+      break;
+
+    case SM_LINE_TABLE:
+      if (ParseLineTable(Record))
+        return Failure;
+      break;
+
+    case SM_SLOC_FILE_ENTRY:
+    case SM_SLOC_BUFFER_ENTRY:
+    case SM_SLOC_INSTANTIATION_ENTRY:
+      // Once we hit one of the source location entries, we're done.
+      return Success;
+    }
+  }
+}
+
+/// \brief Get a cursor that's correctly positioned for reading the source
+/// location entry with the given ID.
+llvm::BitstreamCursor &ASTReader::SLocCursorForID(unsigned ID) {
+  assert(ID != 0 && ID <= TotalNumSLocEntries &&
+         "SLocCursorForID should only be called for real IDs.");
+
+  ID -= 1;
+  PerFileData *F = 0;
+  for (unsigned I = 0, N = Chain.size(); I != N; ++I) {
+    F = Chain[N - I - 1];
+    if (ID < F->LocalNumSLocEntries)
+      break;
+    ID -= F->LocalNumSLocEntries;
+  }
+  assert(F && F->LocalNumSLocEntries > ID && "Chain corrupted");
+
+  F->SLocEntryCursor.JumpToBit(F->SLocOffsets[ID]);
+  return F->SLocEntryCursor;
+}
+
+/// \brief Read in the source location entry with the given ID.
+ASTReader::ASTReadResult ASTReader::ReadSLocEntryRecord(unsigned ID) {
+  if (ID == 0)
+    return Success;
+
+  if (ID > TotalNumSLocEntries) {
+    Error("source location entry ID out-of-range for AST file");
+    return Failure;
+  }
+
+  llvm::BitstreamCursor &SLocEntryCursor = SLocCursorForID(ID);
+
+  ++NumSLocEntriesRead;
+  unsigned Code = SLocEntryCursor.ReadCode();
+  if (Code == llvm::bitc::END_BLOCK ||
+      Code == llvm::bitc::ENTER_SUBBLOCK ||
+      Code == llvm::bitc::DEFINE_ABBREV) {
+    Error("incorrectly-formatted source location entry in AST file");
+    return Failure;
+  }
+
+  RecordData Record;
+  const char *BlobStart;
+  unsigned BlobLen;
+  switch (SLocEntryCursor.ReadRecord(Code, Record, &BlobStart, &BlobLen)) {
+  default:
+    Error("incorrectly-formatted source location entry in AST file");
+    return Failure;
+
+  case SM_SLOC_FILE_ENTRY: {
+    std::string Filename(BlobStart, BlobStart + BlobLen);
+    MaybeAddSystemRootToFilename(Filename);
+    const FileEntry *File = FileMgr.getFile(Filename);
+    if (File == 0) {
+      std::string ErrorStr = "could not find file '";
+      ErrorStr += Filename;
+      ErrorStr += "' referenced by AST file";
+      Error(ErrorStr.c_str());
+      return Failure;
+    }
+
+    if (Record.size() < 10) {
+      Error("source location entry is incorrect");
+      return Failure;
+    }
+
+    if (!DisableValidation &&
+        ((off_t)Record[4] != File->getSize()
+#if !defined(LLVM_ON_WIN32)
+        // In our regression testing, the Windows file system seems to
+        // have inconsistent modification times that sometimes
+        // erroneously trigger this error-handling path.
+         || (time_t)Record[5] != File->getModificationTime()
+#endif
+        )) {
+      Diag(diag::err_fe_pch_file_modified)
+        << Filename;
+      return Failure;
+    }
+
+    FileID FID = SourceMgr.createFileID(File,
+                                SourceLocation::getFromRawEncoding(Record[1]),
+                                       (SrcMgr::CharacteristicKind)Record[2],
+                                        ID, Record[0]);
+    if (Record[3])
+      const_cast<SrcMgr::FileInfo&>(SourceMgr.getSLocEntry(FID).getFile())
+        .setHasLineDirectives();
+
+    // Reconstruct header-search information for this file.
+    HeaderFileInfo HFI;
+    HFI.isImport = Record[6];
+    HFI.DirInfo = Record[7];
+    HFI.NumIncludes = Record[8];
+    HFI.ControllingMacroID = Record[9];
+    if (Listener)
+      Listener->ReadHeaderFileInfo(HFI, File->getUID());
+    break;
+  }
+
+  case SM_SLOC_BUFFER_ENTRY: {
+    const char *Name = BlobStart;
+    unsigned Offset = Record[0];
+    unsigned Code = SLocEntryCursor.ReadCode();
+    Record.clear();
+    unsigned RecCode
+      = SLocEntryCursor.ReadRecord(Code, Record, &BlobStart, &BlobLen);
+
+    if (RecCode != SM_SLOC_BUFFER_BLOB) {
+      Error("AST record has invalid code");
+      return Failure;
+    }
+
+    llvm::MemoryBuffer *Buffer
+    = llvm::MemoryBuffer::getMemBuffer(llvm::StringRef(BlobStart, BlobLen - 1),
+                                       Name);
+    FileID BufferID = SourceMgr.createFileIDForMemBuffer(Buffer, ID, Offset);
+
+    if (strcmp(Name, "<built-in>") == 0) {
+      PCHPredefinesBlock Block = {
+        BufferID,
+        llvm::StringRef(BlobStart, BlobLen - 1)
+      };
+      PCHPredefinesBuffers.push_back(Block);
+    }
+
+    break;
+  }
+
+  case SM_SLOC_INSTANTIATION_ENTRY: {
+    SourceLocation SpellingLoc
+      = SourceLocation::getFromRawEncoding(Record[1]);
+    SourceMgr.createInstantiationLoc(SpellingLoc,
+                              SourceLocation::getFromRawEncoding(Record[2]),
+                              SourceLocation::getFromRawEncoding(Record[3]),
+                                     Record[4],
+                                     ID,
+                                     Record[0]);
+    break;
+  }
+  }
+
+  return Success;
+}
+
+/// ReadBlockAbbrevs - Enter a subblock of the specified BlockID with the
+/// specified cursor.  Read the abbreviations that are at the top of the block
+/// and then leave the cursor pointing into the block.
+bool ASTReader::ReadBlockAbbrevs(llvm::BitstreamCursor &Cursor,
+                                 unsigned BlockID) {
+  if (Cursor.EnterSubBlock(BlockID)) {
+    Error("malformed block record in AST file");
+    return Failure;
+  }
+
+  while (true) {
+    unsigned Code = Cursor.ReadCode();
+
+    // We expect all abbrevs to be at the start of the block.
+    if (Code != llvm::bitc::DEFINE_ABBREV)
+      return false;
+    Cursor.ReadAbbrevRecord();
+  }
+}
+
+void ASTReader::ReadMacroRecord(llvm::BitstreamCursor &Stream, uint64_t Offset){
+  assert(PP && "Forgot to set Preprocessor ?");
+
+  // Keep track of where we are in the stream, then jump back there
+  // after reading this macro.
+  SavedStreamPosition SavedPosition(Stream);
+
+  Stream.JumpToBit(Offset);
+  RecordData Record;
+  llvm::SmallVector<IdentifierInfo*, 16> MacroArgs;
+  MacroInfo *Macro = 0;
+
+  while (true) {
+    unsigned Code = Stream.ReadCode();
+    switch (Code) {
+    case llvm::bitc::END_BLOCK:
+      return;
+
+    case llvm::bitc::ENTER_SUBBLOCK:
+      // No known subblocks, always skip them.
+      Stream.ReadSubBlockID();
+      if (Stream.SkipBlock()) {
+        Error("malformed block record in AST file");
+        return;
+      }
+      continue;
+
+    case llvm::bitc::DEFINE_ABBREV:
+      Stream.ReadAbbrevRecord();
+      continue;
+    default: break;
+    }
+
+    // Read a record.
+    Record.clear();
+    PreprocessorRecordTypes RecType =
+      (PreprocessorRecordTypes)Stream.ReadRecord(Code, Record);
+    switch (RecType) {
+    case PP_MACRO_OBJECT_LIKE:
+    case PP_MACRO_FUNCTION_LIKE: {
+      // If we already have a macro, that means that we've hit the end
+      // of the definition of the macro we were looking for. We're
+      // done.
+      if (Macro)
+        return;
+
+      IdentifierInfo *II = DecodeIdentifierInfo(Record[0]);
+      if (II == 0) {
+        Error("macro must have a name in AST file");
+        return;
+      }
+      SourceLocation Loc = SourceLocation::getFromRawEncoding(Record[1]);
+      bool isUsed = Record[2];
+
+      MacroInfo *MI = PP->AllocateMacroInfo(Loc);
+      MI->setIsUsed(isUsed);
+      MI->setIsFromAST();
+
+      unsigned NextIndex = 3;
+      if (RecType == PP_MACRO_FUNCTION_LIKE) {
+        // Decode function-like macro info.
+        bool isC99VarArgs = Record[3];
+        bool isGNUVarArgs = Record[4];
+        MacroArgs.clear();
+        unsigned NumArgs = Record[5];
+        NextIndex = 6 + NumArgs;
+        for (unsigned i = 0; i != NumArgs; ++i)
+          MacroArgs.push_back(DecodeIdentifierInfo(Record[6+i]));
+
+        // Install function-like macro info.
+        MI->setIsFunctionLike();
+        if (isC99VarArgs) MI->setIsC99Varargs();
+        if (isGNUVarArgs) MI->setIsGNUVarargs();
+        MI->setArgumentList(MacroArgs.data(), MacroArgs.size(),
+                            PP->getPreprocessorAllocator());
+      }
+
+      // Finally, install the macro.
+      PP->setMacroInfo(II, MI);
+
+      // Remember that we saw this macro last so that we add the tokens that
+      // form its body to it.
+      Macro = MI;
+      
+      if (NextIndex + 1 == Record.size() && PP->getPreprocessingRecord()) {
+        // We have a macro definition. Load it now.
+        PP->getPreprocessingRecord()->RegisterMacroDefinition(Macro,
+                                        getMacroDefinition(Record[NextIndex]));
+      }
+      
+      ++NumMacrosRead;
+      break;
+    }
+
+    case PP_TOKEN: {
+      // If we see a TOKEN before a PP_MACRO_*, then the file is
+      // erroneous, just pretend we didn't see this.
+      if (Macro == 0) break;
+
+      Token Tok;
+      Tok.startToken();
+      Tok.setLocation(SourceLocation::getFromRawEncoding(Record[0]));
+      Tok.setLength(Record[1]);
+      if (IdentifierInfo *II = DecodeIdentifierInfo(Record[2]))
+        Tok.setIdentifierInfo(II);
+      Tok.setKind((tok::TokenKind)Record[3]);
+      Tok.setFlag((Token::TokenFlags)Record[4]);
+      Macro->AddTokenToBody(Tok);
+      break;
+    }
+        
+    case PP_MACRO_INSTANTIATION: {
+      // If we already have a macro, that means that we've hit the end
+      // of the definition of the macro we were looking for. We're
+      // done.
+      if (Macro)
+        return;
+      
+      if (!PP->getPreprocessingRecord()) {
+        Error("missing preprocessing record in AST file");
+        return;
+      }
+        
+      PreprocessingRecord &PPRec = *PP->getPreprocessingRecord();
+      if (PPRec.getPreprocessedEntity(Record[0]))
+        return;
+
+      MacroInstantiation *MI
+        = new (PPRec) MacroInstantiation(DecodeIdentifierInfo(Record[3]),
+                               SourceRange(
+                                 SourceLocation::getFromRawEncoding(Record[1]),
+                                 SourceLocation::getFromRawEncoding(Record[2])),
+                                         getMacroDefinition(Record[4]));
+      PPRec.SetPreallocatedEntity(Record[0], MI);
+      return;
+    }
+
+    case PP_MACRO_DEFINITION: {
+      // If we already have a macro, that means that we've hit the end
+      // of the definition of the macro we were looking for. We're
+      // done.
+      if (Macro)
+        return;
+      
+      if (!PP->getPreprocessingRecord()) {
+        Error("missing preprocessing record in AST file");
+        return;
+      }
+      
+      PreprocessingRecord &PPRec = *PP->getPreprocessingRecord();
+      if (PPRec.getPreprocessedEntity(Record[0]))
+        return;
+        
+      if (Record[1] >= MacroDefinitionsLoaded.size()) {
+        Error("out-of-bounds macro definition record");
+        return;
+      }
+
+      MacroDefinition *MD
+        = new (PPRec) MacroDefinition(DecodeIdentifierInfo(Record[4]),
+                                SourceLocation::getFromRawEncoding(Record[5]),
+                              SourceRange(
+                                SourceLocation::getFromRawEncoding(Record[2]),
+                                SourceLocation::getFromRawEncoding(Record[3])));
+      PPRec.SetPreallocatedEntity(Record[0], MD);
+      MacroDefinitionsLoaded[Record[1]] = MD;
+      return;
+    }
+  }
+  }
+}
+
+void ASTReader::ReadDefinedMacros() {
+  for (unsigned I = 0, N = Chain.size(); I != N; ++I) {
+    llvm::BitstreamCursor &MacroCursor = Chain[N - I - 1]->MacroCursor;
+
+    // If there was no preprocessor block, skip this file.
+    if (!MacroCursor.getBitStreamReader())
+      continue;
+
+    llvm::BitstreamCursor Cursor = MacroCursor;
+    if (Cursor.EnterSubBlock(PREPROCESSOR_BLOCK_ID)) {
+      Error("malformed preprocessor block record in AST file");
+      return;
+    }
+
+    RecordData Record;
+    while (true) {
+      unsigned Code = Cursor.ReadCode();
+      if (Code == llvm::bitc::END_BLOCK) {
+        if (Cursor.ReadBlockEnd()) {
+          Error("error at end of preprocessor block in AST file");
+          return;
+        }
+        break;
+      }
+
+      if (Code == llvm::bitc::ENTER_SUBBLOCK) {
+        // No known subblocks, always skip them.
+        Cursor.ReadSubBlockID();
+        if (Cursor.SkipBlock()) {
+          Error("malformed block record in AST file");
+          return;
+        }
+        continue;
+      }
+
+      if (Code == llvm::bitc::DEFINE_ABBREV) {
+        Cursor.ReadAbbrevRecord();
+        continue;
+      }
+
+      // Read a record.
+      const char *BlobStart;
+      unsigned BlobLen;
+      Record.clear();
+      switch (Cursor.ReadRecord(Code, Record, &BlobStart, &BlobLen)) {
+      default:  // Default behavior: ignore.
+        break;
+
+      case PP_MACRO_OBJECT_LIKE:
+      case PP_MACRO_FUNCTION_LIKE:
+        DecodeIdentifierInfo(Record[0]);
+        break;
+
+      case PP_TOKEN:
+        // Ignore tokens.
+        break;
+        
+      case PP_MACRO_INSTANTIATION:
+      case PP_MACRO_DEFINITION:
+        // Read the macro record.
+        ReadMacroRecord(Chain[N - I - 1]->Stream, Cursor.GetCurrentBitNo());
+        break;
+      }
+    }
+  }
+}
+
+MacroDefinition *ASTReader::getMacroDefinition(IdentID ID) {
+  if (ID == 0 || ID >= MacroDefinitionsLoaded.size())
+    return 0;
+
+  if (!MacroDefinitionsLoaded[ID]) {
+    unsigned Index = ID;
+    for (unsigned I = 0, N = Chain.size(); I != N; ++I) {
+      PerFileData &F = *Chain[N - I - 1];
+      if (Index < F.LocalNumMacroDefinitions) {
+        ReadMacroRecord(F.Stream, F.MacroDefinitionOffsets[Index]);
+        break;
+      }
+      Index -= F.LocalNumMacroDefinitions;
+    }
+    assert(MacroDefinitionsLoaded[ID] && "Broken chain");
+  }
+
+  return MacroDefinitionsLoaded[ID];
+}
+
+/// \brief If we are loading a relocatable PCH file, and the filename is
+/// not an absolute path, add the system root to the beginning of the file
+/// name.
+void ASTReader::MaybeAddSystemRootToFilename(std::string &Filename) {
+  // If this is not a relocatable PCH file, there's nothing to do.
+  if (!RelocatablePCH)
+    return;
+
+  if (Filename.empty() || llvm::sys::Path(Filename).isAbsolute())
+    return;
+
+  if (isysroot == 0) {
+    // If no system root was given, default to '/'
+    Filename.insert(Filename.begin(), '/');
+    return;
+  }
+
+  unsigned Length = strlen(isysroot);
+  if (isysroot[Length - 1] != '/')
+    Filename.insert(Filename.begin(), '/');
+
+  Filename.insert(Filename.begin(), isysroot, isysroot + Length);
+}
+
+ASTReader::ASTReadResult
+ASTReader::ReadASTBlock(PerFileData &F) {
+  llvm::BitstreamCursor &Stream = F.Stream;
+
+  if (Stream.EnterSubBlock(AST_BLOCK_ID)) {
+    Error("malformed block record in AST file");
+    return Failure;
+  }
+
+  // Read all of the records and blocks for the ASt file.
+  RecordData Record;
+  bool First = true;
+  while (!Stream.AtEndOfStream()) {
+    unsigned Code = Stream.ReadCode();
+    if (Code == llvm::bitc::END_BLOCK) {
+      if (Stream.ReadBlockEnd()) {
+        Error("error at end of module block in AST file");
+        return Failure;
+      }
+
+      return Success;
+    }
+
+    if (Code == llvm::bitc::ENTER_SUBBLOCK) {
+      switch (Stream.ReadSubBlockID()) {
+      case DECLTYPES_BLOCK_ID:
+        // We lazily load the decls block, but we want to set up the
+        // DeclsCursor cursor to point into it.  Clone our current bitcode
+        // cursor to it, enter the block and read the abbrevs in that block.
+        // With the main cursor, we just skip over it.
+        F.DeclsCursor = Stream;
+        if (Stream.SkipBlock() ||  // Skip with the main cursor.
+            // Read the abbrevs.
+            ReadBlockAbbrevs(F.DeclsCursor, DECLTYPES_BLOCK_ID)) {
+          Error("malformed block record in AST file");
+          return Failure;
+        }
+        break;
+
+      case PREPROCESSOR_BLOCK_ID:
+        F.MacroCursor = Stream;
+        if (PP)
+          PP->setExternalSource(this);
+
+        if (Stream.SkipBlock()) {
+          Error("malformed block record in AST file");
+          return Failure;
+        }
+        break;
+
+      case SOURCE_MANAGER_BLOCK_ID:
+        switch (ReadSourceManagerBlock(F)) {
+        case Success:
+          break;
+
+        case Failure:
+          Error("malformed source manager block in AST file");
+          return Failure;
+
+        case IgnorePCH:
+          return IgnorePCH;
+        }
+        break;
+      }
+      First = false;
+      continue;
+    }
+
+    if (Code == llvm::bitc::DEFINE_ABBREV) {
+      Stream.ReadAbbrevRecord();
+      continue;
+    }
+
+    // Read and process a record.
+    Record.clear();
+    const char *BlobStart = 0;
+    unsigned BlobLen = 0;
+    switch ((ASTRecordTypes)Stream.ReadRecord(Code, Record,
+                                                   &BlobStart, &BlobLen)) {
+    default:  // Default behavior: ignore.
+      break;
+
+    case METADATA: {
+      if (Record[0] != VERSION_MAJOR && !DisableValidation) {
+        Diag(Record[0] < VERSION_MAJOR? diag::warn_pch_version_too_old
+                                           : diag::warn_pch_version_too_new);
+        return IgnorePCH;
+      }
+
+      RelocatablePCH = Record[4];
+      if (Listener) {
+        std::string TargetTriple(BlobStart, BlobLen);
+        if (Listener->ReadTargetTriple(TargetTriple))
+          return IgnorePCH;
+      }
+      break;
+    }
+
+    case CHAINED_METADATA: {
+      if (!First) {
+        Error("CHAINED_METADATA is not first record in block");
+        return Failure;
+      }
+      if (Record[0] != VERSION_MAJOR && !DisableValidation) {
+        Diag(Record[0] < VERSION_MAJOR? diag::warn_pch_version_too_old
+                                           : diag::warn_pch_version_too_new);
+        return IgnorePCH;
+      }
+
+      // Load the chained file.
+      switch(ReadASTCore(llvm::StringRef(BlobStart, BlobLen))) {
+      case Failure: return Failure;
+        // If we have to ignore the dependency, we'll have to ignore this too.
+      case IgnorePCH: return IgnorePCH;
+      case Success: break;
+      }
+      break;
+    }
+
+    case TYPE_OFFSET:
+      if (F.LocalNumTypes != 0) {
+        Error("duplicate TYPE_OFFSET record in AST file");
+        return Failure;
+      }
+      F.TypeOffsets = (const uint32_t *)BlobStart;
+      F.LocalNumTypes = Record[0];
+      break;
+
+    case DECL_OFFSET:
+      if (F.LocalNumDecls != 0) {
+        Error("duplicate DECL_OFFSET record in AST file");
+        return Failure;
+      }
+      F.DeclOffsets = (const uint32_t *)BlobStart;
+      F.LocalNumDecls = Record[0];
+      break;
+
+    case TU_UPDATE_LEXICAL: {
+      DeclContextInfo Info = {
+        /* No visible information */ 0,
+        reinterpret_cast<const DeclID *>(BlobStart),
+        BlobLen / sizeof(DeclID)
+      };
+      DeclContextOffsets[Context->getTranslationUnitDecl()].push_back(Info);
+      break;
+    }
+
+    case UPDATE_VISIBLE: {
+      serialization::DeclID ID = Record[0];
+      void *Table = ASTDeclContextNameLookupTable::Create(
+                        (const unsigned char *)BlobStart + Record[1],
+                        (const unsigned char *)BlobStart,
+                        ASTDeclContextNameLookupTrait(*this));
+      if (ID == 1) { // Is it the TU?
+        DeclContextInfo Info = {
+          Table, /* No lexical inforamtion */ 0, 0
+        };
+        DeclContextOffsets[Context->getTranslationUnitDecl()].push_back(Info);
+      } else
+        PendingVisibleUpdates[ID].push_back(Table);
+      break;
+    }
+
+    case REDECLS_UPDATE_LATEST: {
+      assert(Record.size() % 2 == 0 && "Expected pairs of DeclIDs");
+      for (unsigned i = 0, e = Record.size(); i < e; i += 2) {
+        DeclID First = Record[i], Latest = Record[i+1];
+        assert((FirstLatestDeclIDs.find(First) == FirstLatestDeclIDs.end() ||
+                Latest > FirstLatestDeclIDs[First]) &&
+               "The new latest is supposed to come after the previous latest");
+        FirstLatestDeclIDs[First] = Latest;
+      }
+      break;
+    }
+
+    case LANGUAGE_OPTIONS:
+      if (ParseLanguageOptions(Record) && !DisableValidation)
+        return IgnorePCH;
+      break;
+
+    case IDENTIFIER_TABLE:
+      F.IdentifierTableData = BlobStart;
+      if (Record[0]) {
+        F.IdentifierLookupTable
+          = ASTIdentifierLookupTable::Create(
+                       (const unsigned char *)F.IdentifierTableData + Record[0],
+                       (const unsigned char *)F.IdentifierTableData,
+                       ASTIdentifierLookupTrait(*this, F.Stream));
+        if (PP)
+          PP->getIdentifierTable().setExternalIdentifierLookup(this);
+      }
+      break;
+
+    case IDENTIFIER_OFFSET:
+      if (F.LocalNumIdentifiers != 0) {
+        Error("duplicate IDENTIFIER_OFFSET record in AST file");
+        return Failure;
+      }
+      F.IdentifierOffsets = (const uint32_t *)BlobStart;
+      F.LocalNumIdentifiers = Record[0];
+      break;
+
+    case EXTERNAL_DEFINITIONS:
+      // Optimization for the first block.
+      if (ExternalDefinitions.empty())
+        ExternalDefinitions.swap(Record);
+      else
+        ExternalDefinitions.insert(ExternalDefinitions.end(),
+                                   Record.begin(), Record.end());
+      break;
+
+    case SPECIAL_TYPES:
+      // Optimization for the first block
+      if (SpecialTypes.empty())
+        SpecialTypes.swap(Record);
+      else
+        SpecialTypes.insert(SpecialTypes.end(), Record.begin(), Record.end());
+      break;
+
+    case STATISTICS:
+      TotalNumStatements += Record[0];
+      TotalNumMacros += Record[1];
+      TotalLexicalDeclContexts += Record[2];
+      TotalVisibleDeclContexts += Record[3];
+      break;
+
+    case TENTATIVE_DEFINITIONS:
+      // Optimization for the first block.
+      if (TentativeDefinitions.empty())
+        TentativeDefinitions.swap(Record);
+      else
+        TentativeDefinitions.insert(TentativeDefinitions.end(),
+                                    Record.begin(), Record.end());
+      break;
+
+    case UNUSED_FILESCOPED_DECLS:
+      // Optimization for the first block.
+      if (UnusedFileScopedDecls.empty())
+        UnusedFileScopedDecls.swap(Record);
+      else
+        UnusedFileScopedDecls.insert(UnusedFileScopedDecls.end(),
+                                     Record.begin(), Record.end());
+      break;
+
+    case WEAK_UNDECLARED_IDENTIFIERS:
+      // Later blocks overwrite earlier ones.
+      WeakUndeclaredIdentifiers.swap(Record);
+      break;
+
+    case LOCALLY_SCOPED_EXTERNAL_DECLS:
+      // Optimization for the first block.
+      if (LocallyScopedExternalDecls.empty())
+        LocallyScopedExternalDecls.swap(Record);
+      else
+        LocallyScopedExternalDecls.insert(LocallyScopedExternalDecls.end(),
+                                          Record.begin(), Record.end());
+      break;
+
+    case SELECTOR_OFFSETS:
+      F.SelectorOffsets = (const uint32_t *)BlobStart;
+      F.LocalNumSelectors = Record[0];
+      break;
+
+    case METHOD_POOL:
+      F.SelectorLookupTableData = (const unsigned char *)BlobStart;
+      if (Record[0])
+        F.SelectorLookupTable
+          = ASTSelectorLookupTable::Create(
+                        F.SelectorLookupTableData + Record[0],
+                        F.SelectorLookupTableData,
+                        ASTSelectorLookupTrait(*this));
+      TotalNumMethodPoolEntries += Record[1];
+      break;
+
+    case REFERENCED_SELECTOR_POOL: {
+      ReferencedSelectorsData.insert(ReferencedSelectorsData.end(),
+          Record.begin(), Record.end());
+      break;
+    }
+
+    case PP_COUNTER_VALUE:
+      if (!Record.empty() && Listener)
+        Listener->ReadCounter(Record[0]);
+      break;
+
+    case SOURCE_LOCATION_OFFSETS:
+      F.SLocOffsets = (const uint32_t *)BlobStart;
+      F.LocalNumSLocEntries = Record[0];
+      // We cannot delay this until the entire chain is loaded, because then
+      // source location preloads would also have to be delayed.
+      // FIXME: Is there a reason not to do that?
+      TotalNumSLocEntries += F.LocalNumSLocEntries;
+      SourceMgr.PreallocateSLocEntries(this, TotalNumSLocEntries, Record[1]);
+      break;
+
+    case SOURCE_LOCATION_PRELOADS:
+      for (unsigned I = 0, N = Record.size(); I != N; ++I) {
+        ASTReadResult Result = ReadSLocEntryRecord(Record[I]);
+        if (Result != Success)
+          return Result;
+      }
+      break;
+
+    case STAT_CACHE: {
+      ASTStatCache *MyStatCache =
+        new ASTStatCache((const unsigned char *)BlobStart + Record[0],
+                         (const unsigned char *)BlobStart,
+                         NumStatHits, NumStatMisses);
+      FileMgr.addStatCache(MyStatCache);
+      F.StatCache = MyStatCache;
+      break;
+    }
+
+    case EXT_VECTOR_DECLS:
+      // Optimization for the first block.
+      if (ExtVectorDecls.empty())
+        ExtVectorDecls.swap(Record);
+      else
+        ExtVectorDecls.insert(ExtVectorDecls.end(),
+                              Record.begin(), Record.end());
+      break;
+
+    case VTABLE_USES:
+      // Later tables overwrite earlier ones.
+      VTableUses.swap(Record);
+      break;
+
+    case DYNAMIC_CLASSES:
+      // Optimization for the first block.
+      if (DynamicClasses.empty())
+        DynamicClasses.swap(Record);
+      else
+        DynamicClasses.insert(DynamicClasses.end(),
+                              Record.begin(), Record.end());
+      break;
+
+    case PENDING_IMPLICIT_INSTANTIATIONS:
+      // Optimization for the first block.
+      if (PendingInstantiations.empty())
+        PendingInstantiations.swap(Record);
+      else
+        PendingInstantiations.insert(PendingInstantiations.end(),
+                                     Record.begin(), Record.end());
+      break;
+
+    case SEMA_DECL_REFS:
+      // Later tables overwrite earlier ones.
+      SemaDeclRefs.swap(Record);
+      break;
+
+    case ORIGINAL_FILE_NAME:
+      // The primary AST will be the last to get here, so it will be the one
+      // that's used.
+      ActualOriginalFileName.assign(BlobStart, BlobLen);
+      OriginalFileName = ActualOriginalFileName;
+      MaybeAddSystemRootToFilename(OriginalFileName);
+      break;
+
+    case VERSION_CONTROL_BRANCH_REVISION: {
+      const std::string &CurBranch = getClangFullRepositoryVersion();
+      llvm::StringRef ASTBranch(BlobStart, BlobLen);
+      if (llvm::StringRef(CurBranch) != ASTBranch && !DisableValidation) {
+        Diag(diag::warn_pch_different_branch) << ASTBranch << CurBranch;
+        return IgnorePCH;
+      }
+      break;
+    }
+
+    case MACRO_DEFINITION_OFFSETS:
+      F.MacroDefinitionOffsets = (const uint32_t *)BlobStart;
+      F.NumPreallocatedPreprocessingEntities = Record[0];
+      F.LocalNumMacroDefinitions = Record[1];
+      break;
+
+    case DECL_REPLACEMENTS: {
+      if (Record.size() % 2 != 0) {
+        Error("invalid DECL_REPLACEMENTS block in AST file");
+        return Failure;
+      }
+      for (unsigned I = 0, N = Record.size(); I != N; I += 2)
+        ReplacedDecls[static_cast<DeclID>(Record[I])] =
+            std::make_pair(&F, Record[I+1]);
+      break;
+    }
+
+    case ADDITIONAL_TEMPLATE_SPECIALIZATIONS: {
+      AdditionalTemplateSpecializations &ATS =
+          AdditionalTemplateSpecializationsPending[Record[0]];
+      ATS.insert(ATS.end(), Record.begin()+1, Record.end());
+      break;
+    }
+    }
+    First = false;
+  }
+  Error("premature end of bitstream in AST file");
+  return Failure;
+}
+
+ASTReader::ASTReadResult ASTReader::ReadAST(const std::string &FileName) {
+  switch(ReadASTCore(FileName)) {
+  case Failure: return Failure;
+  case IgnorePCH: return IgnorePCH;
+  case Success: break;
+  }
+
+  // Here comes stuff that we only do once the entire chain is loaded.
+
+  // Allocate space for loaded identifiers, decls and types.
+  unsigned TotalNumIdentifiers = 0, TotalNumTypes = 0, TotalNumDecls = 0,
+           TotalNumPreallocatedPreprocessingEntities = 0, TotalNumMacroDefs = 0,
+           TotalNumSelectors = 0;
+  for (unsigned I = 0, N = Chain.size(); I != N; ++I) {
+    TotalNumIdentifiers += Chain[I]->LocalNumIdentifiers;
+    TotalNumTypes += Chain[I]->LocalNumTypes;
+    TotalNumDecls += Chain[I]->LocalNumDecls;
+    TotalNumPreallocatedPreprocessingEntities +=
+        Chain[I]->NumPreallocatedPreprocessingEntities;
+    TotalNumMacroDefs += Chain[I]->LocalNumMacroDefinitions;
+    TotalNumSelectors += Chain[I]->LocalNumSelectors;
+  }
+  IdentifiersLoaded.resize(TotalNumIdentifiers);
+  TypesLoaded.resize(TotalNumTypes);
+  DeclsLoaded.resize(TotalNumDecls);
+  MacroDefinitionsLoaded.resize(TotalNumMacroDefs);
+  if (PP) {
+    if (TotalNumIdentifiers > 0)
+      PP->getHeaderSearchInfo().SetExternalLookup(this);
+    if (TotalNumPreallocatedPreprocessingEntities > 0) {
+      if (!PP->getPreprocessingRecord())
+        PP->createPreprocessingRecord();
+      PP->getPreprocessingRecord()->SetExternalSource(*this,
+                                     TotalNumPreallocatedPreprocessingEntities);
+    }
+  }
+  SelectorsLoaded.resize(TotalNumSelectors);
+
+  // Check the predefines buffers.
+  if (!DisableValidation && CheckPredefinesBuffers())
+    return IgnorePCH;
+
+  if (PP) {
+    // Initialization of keywords and pragmas occurs before the
+    // AST file is read, so there may be some identifiers that were
+    // loaded into the IdentifierTable before we intercepted the
+    // creation of identifiers. Iterate through the list of known
+    // identifiers and determine whether we have to establish
+    // preprocessor definitions or top-level identifier declaration
+    // chains for those identifiers.
+    //
+    // We copy the IdentifierInfo pointers to a small vector first,
+    // since de-serializing declarations or macro definitions can add
+    // new entries into the identifier table, invalidating the
+    // iterators.
+    llvm::SmallVector<IdentifierInfo *, 128> Identifiers;
+    for (IdentifierTable::iterator Id = PP->getIdentifierTable().begin(),
+                                IdEnd = PP->getIdentifierTable().end();
+         Id != IdEnd; ++Id)
+      Identifiers.push_back(Id->second);
+    // We need to search the tables in all files.
+    for (unsigned J = 0, M = Chain.size(); J != M; ++J) {
+      ASTIdentifierLookupTable *IdTable
+        = (ASTIdentifierLookupTable *)Chain[J]->IdentifierLookupTable;
+      // Not all AST files necessarily have identifier tables, only the useful
+      // ones.
+      if (!IdTable)
+        continue;
+      for (unsigned I = 0, N = Identifiers.size(); I != N; ++I) {
+        IdentifierInfo *II = Identifiers[I];
+        // Look in the on-disk hash tables for an entry for this identifier
+        ASTIdentifierLookupTrait Info(*this, Chain[J]->Stream, II);
+        std::pair<const char*,unsigned> Key(II->getNameStart(),II->getLength());
+        ASTIdentifierLookupTable::iterator Pos = IdTable->find(Key, &Info);
+        if (Pos == IdTable->end())
+          continue;
+
+        // Dereferencing the iterator has the effect of populating the
+        // IdentifierInfo node with the various declarations it needs.
+        (void)*Pos;
+      }
+    }
+  }
+
+  if (Context)
+    InitializeContext(*Context);
+
+  return Success;
+}
+
+ASTReader::ASTReadResult ASTReader::ReadASTCore(llvm::StringRef FileName) {
+  Chain.push_back(new PerFileData());
+  PerFileData &F = *Chain.back();
+
+  // Set the AST file name.
+  F.FileName = FileName;
+
+  // Open the AST file.
+  //
+  // FIXME: This shouldn't be here, we should just take a raw_ostream.
+  std::string ErrStr;
+  F.Buffer.reset(llvm::MemoryBuffer::getFileOrSTDIN(FileName, &ErrStr));
+  if (!F.Buffer) {
+    Error(ErrStr.c_str());
+    return IgnorePCH;
+  }
+
+  // Initialize the stream
+  F.StreamFile.init((const unsigned char *)F.Buffer->getBufferStart(),
+                    (const unsigned char *)F.Buffer->getBufferEnd());
+  llvm::BitstreamCursor &Stream = F.Stream;
+  Stream.init(F.StreamFile);
+  F.SizeInBits = F.Buffer->getBufferSize() * 8;
+
+  // Sniff for the signature.
+  if (Stream.Read(8) != 'C' ||
+      Stream.Read(8) != 'P' ||
+      Stream.Read(8) != 'C' ||
+      Stream.Read(8) != 'H') {
+    Diag(diag::err_not_a_pch_file) << FileName;
+    return Failure;
+  }
+
+  while (!Stream.AtEndOfStream()) {
+    unsigned Code = Stream.ReadCode();
+
+    if (Code != llvm::bitc::ENTER_SUBBLOCK) {
+      Error("invalid record at top-level of AST file");
+      return Failure;
+    }
+
+    unsigned BlockID = Stream.ReadSubBlockID();
+
+    // We only know the AST subblock ID.
+    switch (BlockID) {
+    case llvm::bitc::BLOCKINFO_BLOCK_ID:
+      if (Stream.ReadBlockInfoBlock()) {
+        Error("malformed BlockInfoBlock in AST file");
+        return Failure;
+      }
+      break;
+    case AST_BLOCK_ID:
+      switch (ReadASTBlock(F)) {
+      case Success:
+        break;
+
+      case Failure:
+        return Failure;
+
+      case IgnorePCH:
+        // FIXME: We could consider reading through to the end of this
+        // AST block, skipping subblocks, to see if there are other
+        // AST blocks elsewhere.
+
+        // Clear out any preallocated source location entries, so that
+        // the source manager does not try to resolve them later.
+        SourceMgr.ClearPreallocatedSLocEntries();
+
+        // Remove the stat cache.
+        if (F.StatCache)
+          FileMgr.removeStatCache((ASTStatCache*)F.StatCache);
+
+        return IgnorePCH;
+      }
+      break;
+    default:
+      if (Stream.SkipBlock()) {
+        Error("malformed block record in AST file");
+        return Failure;
+      }
+      break;
+    }
+  }
+
+  return Success;
+}
+
+void ASTReader::setPreprocessor(Preprocessor &pp) {
+  PP = &pp;
+
+  unsigned TotalNum = 0;
+  for (unsigned I = 0, N = Chain.size(); I != N; ++I)
+    TotalNum += Chain[I]->NumPreallocatedPreprocessingEntities;
+  if (TotalNum) {
+    if (!PP->getPreprocessingRecord())
+      PP->createPreprocessingRecord();
+    PP->getPreprocessingRecord()->SetExternalSource(*this, TotalNum);
+  }
+}
+
+void ASTReader::InitializeContext(ASTContext &Ctx) {
+  Context = &Ctx;
+  assert(Context && "Passed null context!");
+
+  assert(PP && "Forgot to set Preprocessor ?");
+  PP->getIdentifierTable().setExternalIdentifierLookup(this);
+  PP->getHeaderSearchInfo().SetExternalLookup(this);
+  PP->setExternalSource(this);
+
+  // Load the translation unit declaration
+  GetTranslationUnitDecl();
+
+  // Load the special types.
+  Context->setBuiltinVaListType(
+    GetType(SpecialTypes[SPECIAL_TYPE_BUILTIN_VA_LIST]));
+  if (unsigned Id = SpecialTypes[SPECIAL_TYPE_OBJC_ID])
+    Context->setObjCIdType(GetType(Id));
+  if (unsigned Sel = SpecialTypes[SPECIAL_TYPE_OBJC_SELECTOR])
+    Context->setObjCSelType(GetType(Sel));
+  if (unsigned Proto = SpecialTypes[SPECIAL_TYPE_OBJC_PROTOCOL])
+    Context->setObjCProtoType(GetType(Proto));
+  if (unsigned Class = SpecialTypes[SPECIAL_TYPE_OBJC_CLASS])
+    Context->setObjCClassType(GetType(Class));
+
+  if (unsigned String = SpecialTypes[SPECIAL_TYPE_CF_CONSTANT_STRING])
+    Context->setCFConstantStringType(GetType(String));
+  if (unsigned FastEnum
+        = SpecialTypes[SPECIAL_TYPE_OBJC_FAST_ENUMERATION_STATE])
+    Context->setObjCFastEnumerationStateType(GetType(FastEnum));
+  if (unsigned File = SpecialTypes[SPECIAL_TYPE_FILE]) {
+    QualType FileType = GetType(File);
+    if (FileType.isNull()) {
+      Error("FILE type is NULL");
+      return;
+    }
+    if (const TypedefType *Typedef = FileType->getAs<TypedefType>())
+      Context->setFILEDecl(Typedef->getDecl());
+    else {
+      const TagType *Tag = FileType->getAs<TagType>();
+      if (!Tag) {
+        Error("Invalid FILE type in AST file");
+        return;
+      }
+      Context->setFILEDecl(Tag->getDecl());
+    }
+  }
+  if (unsigned Jmp_buf = SpecialTypes[SPECIAL_TYPE_jmp_buf]) {
+    QualType Jmp_bufType = GetType(Jmp_buf);
+    if (Jmp_bufType.isNull()) {
+      Error("jmp_bug type is NULL");
+      return;
+    }
+    if (const TypedefType *Typedef = Jmp_bufType->getAs<TypedefType>())
+      Context->setjmp_bufDecl(Typedef->getDecl());
+    else {
+      const TagType *Tag = Jmp_bufType->getAs<TagType>();
+      if (!Tag) {
+        Error("Invalid jmp_buf type in AST file");
+        return;
+      }
+      Context->setjmp_bufDecl(Tag->getDecl());
+    }
+  }
+  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 (const TypedefType *Typedef = Sigjmp_bufType->getAs<TypedefType>())
+      Context->setsigjmp_bufDecl(Typedef->getDecl());
+    else {
+      const TagType *Tag = Sigjmp_bufType->getAs<TagType>();
+      assert(Tag && "Invalid sigjmp_buf type in AST file");
+      Context->setsigjmp_bufDecl(Tag->getDecl());
+    }
+  }
+  if (unsigned ObjCIdRedef
+        = SpecialTypes[SPECIAL_TYPE_OBJC_ID_REDEFINITION])
+    Context->ObjCIdRedefinitionType = GetType(ObjCIdRedef);
+  if (unsigned ObjCClassRedef
+      = SpecialTypes[SPECIAL_TYPE_OBJC_CLASS_REDEFINITION])
+    Context->ObjCClassRedefinitionType = GetType(ObjCClassRedef);
+  if (unsigned String = SpecialTypes[SPECIAL_TYPE_BLOCK_DESCRIPTOR])
+    Context->setBlockDescriptorType(GetType(String));
+  if (unsigned String
+      = SpecialTypes[SPECIAL_TYPE_BLOCK_EXTENDED_DESCRIPTOR])
+    Context->setBlockDescriptorExtendedType(GetType(String));
+  if (unsigned ObjCSelRedef
+      = SpecialTypes[SPECIAL_TYPE_OBJC_SEL_REDEFINITION])
+    Context->ObjCSelRedefinitionType = GetType(ObjCSelRedef);
+  if (unsigned String = SpecialTypes[SPECIAL_TYPE_NS_CONSTANT_STRING])
+    Context->setNSConstantStringType(GetType(String));
+
+  if (SpecialTypes[SPECIAL_TYPE_INT128_INSTALLED])
+    Context->setInt128Installed();
+}
+
+/// \brief Retrieve the name of the original source file name
+/// directly from the AST file, without actually loading the AST
+/// file.
+std::string ASTReader::getOriginalSourceFile(const std::string &ASTFileName,
+                                             Diagnostic &Diags) {
+  // Open the AST file.
+  std::string ErrStr;
+  llvm::OwningPtr<llvm::MemoryBuffer> Buffer;
+  Buffer.reset(llvm::MemoryBuffer::getFile(ASTFileName.c_str(), &ErrStr));
+  if (!Buffer) {
+    Diags.Report(diag::err_fe_unable_to_read_pch_file) << ErrStr;
+    return std::string();
+  }
+
+  // Initialize the stream
+  llvm::BitstreamReader StreamFile;
+  llvm::BitstreamCursor Stream;
+  StreamFile.init((const unsigned char *)Buffer->getBufferStart(),
+                  (const unsigned char *)Buffer->getBufferEnd());
+  Stream.init(StreamFile);
+
+  // Sniff for the signature.
+  if (Stream.Read(8) != 'C' ||
+      Stream.Read(8) != 'P' ||
+      Stream.Read(8) != 'C' ||
+      Stream.Read(8) != 'H') {
+    Diags.Report(diag::err_fe_not_a_pch_file) << ASTFileName;
+    return std::string();
+  }
+
+  RecordData Record;
+  while (!Stream.AtEndOfStream()) {
+    unsigned Code = Stream.ReadCode();
+
+    if (Code == llvm::bitc::ENTER_SUBBLOCK) {
+      unsigned BlockID = Stream.ReadSubBlockID();
+
+      // We only know the AST subblock ID.
+      switch (BlockID) {
+      case AST_BLOCK_ID:
+        if (Stream.EnterSubBlock(AST_BLOCK_ID)) {
+          Diags.Report(diag::err_fe_pch_malformed_block) << ASTFileName;
+          return std::string();
+        }
+        break;
+
+      default:
+        if (Stream.SkipBlock()) {
+          Diags.Report(diag::err_fe_pch_malformed_block) << ASTFileName;
+          return std::string();
+        }
+        break;
+      }
+      continue;
+    }
+
+    if (Code == llvm::bitc::END_BLOCK) {
+      if (Stream.ReadBlockEnd()) {
+        Diags.Report(diag::err_fe_pch_error_at_end_block) << ASTFileName;
+        return std::string();
+      }
+      continue;
+    }
+
+    if (Code == llvm::bitc::DEFINE_ABBREV) {
+      Stream.ReadAbbrevRecord();
+      continue;
+    }
+
+    Record.clear();
+    const char *BlobStart = 0;
+    unsigned BlobLen = 0;
+    if (Stream.ReadRecord(Code, Record, &BlobStart, &BlobLen)
+          == ORIGINAL_FILE_NAME)
+      return std::string(BlobStart, BlobLen);
+  }
+
+  return std::string();
+}
+
+/// \brief Parse the record that corresponds to a LangOptions data
+/// structure.
+///
+/// This routine parses the language options from the AST file and then gives
+/// them to the AST listener if one is set.
+///
+/// \returns true if the listener deems the file unacceptable, false otherwise.
+bool ASTReader::ParseLanguageOptions(
+                             const llvm::SmallVectorImpl<uint64_t> &Record) {
+  if (Listener) {
+    LangOptions LangOpts;
+
+  #define PARSE_LANGOPT(Option)                  \
+      LangOpts.Option = Record[Idx];             \
+      ++Idx
+
+    unsigned Idx = 0;
+    PARSE_LANGOPT(Trigraphs);
+    PARSE_LANGOPT(BCPLComment);
+    PARSE_LANGOPT(DollarIdents);
+    PARSE_LANGOPT(AsmPreprocessor);
+    PARSE_LANGOPT(GNUMode);
+    PARSE_LANGOPT(GNUKeywords);
+    PARSE_LANGOPT(ImplicitInt);
+    PARSE_LANGOPT(Digraphs);
+    PARSE_LANGOPT(HexFloats);
+    PARSE_LANGOPT(C99);
+    PARSE_LANGOPT(Microsoft);
+    PARSE_LANGOPT(CPlusPlus);
+    PARSE_LANGOPT(CPlusPlus0x);
+    PARSE_LANGOPT(CXXOperatorNames);
+    PARSE_LANGOPT(ObjC1);
+    PARSE_LANGOPT(ObjC2);
+    PARSE_LANGOPT(ObjCNonFragileABI);
+    PARSE_LANGOPT(ObjCNonFragileABI2);
+    PARSE_LANGOPT(NoConstantCFStrings);
+    PARSE_LANGOPT(PascalStrings);
+    PARSE_LANGOPT(WritableStrings);
+    PARSE_LANGOPT(LaxVectorConversions);
+    PARSE_LANGOPT(AltiVec);
+    PARSE_LANGOPT(Exceptions);
+    PARSE_LANGOPT(SjLjExceptions);
+    PARSE_LANGOPT(NeXTRuntime);
+    PARSE_LANGOPT(Freestanding);
+    PARSE_LANGOPT(NoBuiltin);
+    PARSE_LANGOPT(ThreadsafeStatics);
+    PARSE_LANGOPT(POSIXThreads);
+    PARSE_LANGOPT(Blocks);
+    PARSE_LANGOPT(EmitAllDecls);
+    PARSE_LANGOPT(MathErrno);
+    LangOpts.setSignedOverflowBehavior((LangOptions::SignedOverflowBehaviorTy)
+                                       Record[Idx++]);
+    PARSE_LANGOPT(HeinousExtensions);
+    PARSE_LANGOPT(Optimize);
+    PARSE_LANGOPT(OptimizeSize);
+    PARSE_LANGOPT(Static);
+    PARSE_LANGOPT(PICLevel);
+    PARSE_LANGOPT(GNUInline);
+    PARSE_LANGOPT(NoInline);
+    PARSE_LANGOPT(AccessControl);
+    PARSE_LANGOPT(CharIsSigned);
+    PARSE_LANGOPT(ShortWChar);
+    LangOpts.setGCMode((LangOptions::GCMode)Record[Idx++]);
+    LangOpts.setVisibilityMode((LangOptions::VisibilityMode)Record[Idx++]);
+    LangOpts.setStackProtectorMode((LangOptions::StackProtectorMode)
+                                   Record[Idx++]);
+    PARSE_LANGOPT(InstantiationDepth);
+    PARSE_LANGOPT(OpenCL);
+    PARSE_LANGOPT(CatchUndefined);
+    // FIXME: Missing ElideConstructors?!
+  #undef PARSE_LANGOPT
+
+    return Listener->ReadLanguageOptions(LangOpts);
+  }
+
+  return false;
+}
+
+void ASTReader::ReadPreprocessedEntities() {
+  ReadDefinedMacros();
+}
+
+/// \brief Get the correct cursor and offset for loading a type.
+ASTReader::RecordLocation ASTReader::TypeCursorForIndex(unsigned Index) {
+  PerFileData *F = 0;
+  for (unsigned I = 0, N = Chain.size(); I != N; ++I) {
+    F = Chain[N - I - 1];
+    if (Index < F->LocalNumTypes)
+      break;
+    Index -= F->LocalNumTypes;
+  }
+  assert(F && F->LocalNumTypes > Index && "Broken chain");
+  return RecordLocation(&F->DeclsCursor, F->TypeOffsets[Index]);
+}
+
+/// \brief Read and return the type with the given index..
+///
+/// The index is the type ID, shifted and minus the number of predefs. This
+/// routine actually reads the record corresponding to the type at the given
+/// location. It is a helper routine for GetType, which deals with reading type
+/// IDs.
+QualType ASTReader::ReadTypeRecord(unsigned Index) {
+  RecordLocation Loc = TypeCursorForIndex(Index);
+  llvm::BitstreamCursor &DeclsCursor = *Loc.first;
+
+  // Keep track of where we are in the stream, then jump back there
+  // after reading this type.
+  SavedStreamPosition SavedPosition(DeclsCursor);
+
+  ReadingKindTracker ReadingKind(Read_Type, *this);
+
+  // Note that we are loading a type record.
+  Deserializing AType(this);
+
+  DeclsCursor.JumpToBit(Loc.second);
+  RecordData Record;
+  unsigned Code = DeclsCursor.ReadCode();
+  switch ((TypeCode)DeclsCursor.ReadRecord(Code, Record)) {
+  case TYPE_EXT_QUAL: {
+    if (Record.size() != 2) {
+      Error("Incorrect encoding of extended qualifier type");
+      return QualType();
+    }
+    QualType Base = GetType(Record[0]);
+    Qualifiers Quals = Qualifiers::fromOpaqueValue(Record[1]);
+    return Context->getQualifiedType(Base, Quals);
+  }
+
+  case TYPE_COMPLEX: {
+    if (Record.size() != 1) {
+      Error("Incorrect encoding of complex type");
+      return QualType();
+    }
+    QualType ElemType = GetType(Record[0]);
+    return Context->getComplexType(ElemType);
+  }
+
+  case TYPE_POINTER: {
+    if (Record.size() != 1) {
+      Error("Incorrect encoding of pointer type");
+      return QualType();
+    }
+    QualType PointeeType = GetType(Record[0]);
+    return Context->getPointerType(PointeeType);
+  }
+
+  case TYPE_BLOCK_POINTER: {
+    if (Record.size() != 1) {
+      Error("Incorrect encoding of block pointer type");
+      return QualType();
+    }
+    QualType PointeeType = GetType(Record[0]);
+    return Context->getBlockPointerType(PointeeType);
+  }
+
+  case TYPE_LVALUE_REFERENCE: {
+    if (Record.size() != 1) {
+      Error("Incorrect encoding of lvalue reference type");
+      return QualType();
+    }
+    QualType PointeeType = GetType(Record[0]);
+    return Context->getLValueReferenceType(PointeeType);
+  }
+
+  case TYPE_RVALUE_REFERENCE: {
+    if (Record.size() != 1) {
+      Error("Incorrect encoding of rvalue reference type");
+      return QualType();
+    }
+    QualType PointeeType = GetType(Record[0]);
+    return Context->getRValueReferenceType(PointeeType);
+  }
+
+  case TYPE_MEMBER_POINTER: {
+    if (Record.size() != 2) {
+      Error("Incorrect encoding of member pointer type");
+      return QualType();
+    }
+    QualType PointeeType = GetType(Record[0]);
+    QualType ClassType = GetType(Record[1]);
+    return Context->getMemberPointerType(PointeeType, ClassType.getTypePtr());
+  }
+
+  case TYPE_CONSTANT_ARRAY: {
+    QualType ElementType = GetType(Record[0]);
+    ArrayType::ArraySizeModifier ASM = (ArrayType::ArraySizeModifier)Record[1];
+    unsigned IndexTypeQuals = Record[2];
+    unsigned Idx = 3;
+    llvm::APInt Size = ReadAPInt(Record, Idx);
+    return Context->getConstantArrayType(ElementType, Size,
+                                         ASM, IndexTypeQuals);
+  }
+
+  case TYPE_INCOMPLETE_ARRAY: {
+    QualType ElementType = GetType(Record[0]);
+    ArrayType::ArraySizeModifier ASM = (ArrayType::ArraySizeModifier)Record[1];
+    unsigned IndexTypeQuals = Record[2];
+    return Context->getIncompleteArrayType(ElementType, ASM, IndexTypeQuals);
+  }
+
+  case TYPE_VARIABLE_ARRAY: {
+    QualType ElementType = GetType(Record[0]);
+    ArrayType::ArraySizeModifier ASM = (ArrayType::ArraySizeModifier)Record[1];
+    unsigned IndexTypeQuals = Record[2];
+    SourceLocation LBLoc = SourceLocation::getFromRawEncoding(Record[3]);
+    SourceLocation RBLoc = SourceLocation::getFromRawEncoding(Record[4]);
+    return Context->getVariableArrayType(ElementType, ReadExpr(DeclsCursor),
+                                         ASM, IndexTypeQuals,
+                                         SourceRange(LBLoc, RBLoc));
+  }
+
+  case TYPE_VECTOR: {
+    if (Record.size() != 3) {
+      Error("incorrect encoding of vector type in AST file");
+      return QualType();
+    }
+
+    QualType ElementType = GetType(Record[0]);
+    unsigned NumElements = Record[1];
+    unsigned AltiVecSpec = Record[2];
+    return Context->getVectorType(ElementType, NumElements,
+                                  (VectorType::AltiVecSpecific)AltiVecSpec);
+  }
+
+  case TYPE_EXT_VECTOR: {
+    if (Record.size() != 3) {
+      Error("incorrect encoding of extended vector type in AST file");
+      return QualType();
+    }
+
+    QualType ElementType = GetType(Record[0]);
+    unsigned NumElements = Record[1];
+    return Context->getExtVectorType(ElementType, NumElements);
+  }
+
+  case TYPE_FUNCTION_NO_PROTO: {
+    if (Record.size() != 4) {
+      Error("incorrect encoding of no-proto function type");
+      return QualType();
+    }
+    QualType ResultType = GetType(Record[0]);
+    FunctionType::ExtInfo Info(Record[1], Record[2], (CallingConv)Record[3]);
+    return Context->getFunctionNoProtoType(ResultType, Info);
+  }
+
+  case TYPE_FUNCTION_PROTO: {
+    QualType ResultType = GetType(Record[0]);
+    bool NoReturn = Record[1];
+    unsigned RegParm = Record[2];
+    CallingConv CallConv = (CallingConv)Record[3];
+    unsigned Idx = 4;
+    unsigned NumParams = Record[Idx++];
+    llvm::SmallVector<QualType, 16> ParamTypes;
+    for (unsigned I = 0; I != NumParams; ++I)
+      ParamTypes.push_back(GetType(Record[Idx++]));
+    bool isVariadic = Record[Idx++];
+    unsigned Quals = Record[Idx++];
+    bool hasExceptionSpec = Record[Idx++];
+    bool hasAnyExceptionSpec = Record[Idx++];
+    unsigned NumExceptions = Record[Idx++];
+    llvm::SmallVector<QualType, 2> Exceptions;
+    for (unsigned I = 0; I != NumExceptions; ++I)
+      Exceptions.push_back(GetType(Record[Idx++]));
+    return Context->getFunctionType(ResultType, ParamTypes.data(), NumParams,
+                                    isVariadic, Quals, hasExceptionSpec,
+                                    hasAnyExceptionSpec, NumExceptions,
+                                    Exceptions.data(),
+                                    FunctionType::ExtInfo(NoReturn, RegParm,
+                                                          CallConv));
+  }
+
+  case TYPE_UNRESOLVED_USING:
+    return Context->getTypeDeclType(
+             cast<UnresolvedUsingTypenameDecl>(GetDecl(Record[0])));
+
+  case TYPE_TYPEDEF: {
+    if (Record.size() != 2) {
+      Error("incorrect encoding of typedef type");
+      return QualType();
+    }
+    TypedefDecl *Decl = cast<TypedefDecl>(GetDecl(Record[0]));
+    QualType Canonical = GetType(Record[1]);
+    return Context->getTypedefType(Decl, Canonical);
+  }
+
+  case TYPE_TYPEOF_EXPR:
+    return Context->getTypeOfExprType(ReadExpr(DeclsCursor));
+
+  case TYPE_TYPEOF: {
+    if (Record.size() != 1) {
+      Error("incorrect encoding of typeof(type) in AST file");
+      return QualType();
+    }
+    QualType UnderlyingType = GetType(Record[0]);
+    return Context->getTypeOfType(UnderlyingType);
+  }
+
+  case TYPE_DECLTYPE:
+    return Context->getDecltypeType(ReadExpr(DeclsCursor));
+
+  case TYPE_RECORD: {
+    if (Record.size() != 2) {
+      Error("incorrect encoding of record type");
+      return QualType();
+    }
+    bool IsDependent = Record[0];
+    QualType T = Context->getRecordType(cast<RecordDecl>(GetDecl(Record[1])));
+    T->Dependent = IsDependent;
+    return T;
+  }
+
+  case TYPE_ENUM: {
+    if (Record.size() != 2) {
+      Error("incorrect encoding of enum type");
+      return QualType();
+    }
+    bool IsDependent = Record[0];
+    QualType T = Context->getEnumType(cast<EnumDecl>(GetDecl(Record[1])));
+    T->Dependent = IsDependent;
+    return T;
+  }
+
+  case TYPE_ELABORATED: {
+    unsigned Idx = 0;
+    ElaboratedTypeKeyword Keyword = (ElaboratedTypeKeyword)Record[Idx++];
+    NestedNameSpecifier *NNS = ReadNestedNameSpecifier(Record, Idx);
+    QualType NamedType = GetType(Record[Idx++]);
+    return Context->getElaboratedType(Keyword, NNS, NamedType);
+  }
+
+  case TYPE_OBJC_INTERFACE: {
+    unsigned Idx = 0;
+    ObjCInterfaceDecl *ItfD = cast<ObjCInterfaceDecl>(GetDecl(Record[Idx++]));
+    return Context->getObjCInterfaceType(ItfD);
+  }
+
+  case TYPE_OBJC_OBJECT: {
+    unsigned Idx = 0;
+    QualType Base = GetType(Record[Idx++]);
+    unsigned NumProtos = Record[Idx++];
+    llvm::SmallVector<ObjCProtocolDecl*, 4> Protos;
+    for (unsigned I = 0; I != NumProtos; ++I)
+      Protos.push_back(cast<ObjCProtocolDecl>(GetDecl(Record[Idx++])));
+    return Context->getObjCObjectType(Base, Protos.data(), NumProtos);    
+  }
+
+  case TYPE_OBJC_OBJECT_POINTER: {
+    unsigned Idx = 0;
+    QualType Pointee = GetType(Record[Idx++]);
+    return Context->getObjCObjectPointerType(Pointee);
+  }
+
+  case TYPE_SUBST_TEMPLATE_TYPE_PARM: {
+    unsigned Idx = 0;
+    QualType Parm = GetType(Record[Idx++]);
+    QualType Replacement = GetType(Record[Idx++]);
+    return
+      Context->getSubstTemplateTypeParmType(cast<TemplateTypeParmType>(Parm),
+                                            Replacement);
+  }
+
+  case TYPE_INJECTED_CLASS_NAME: {
+    CXXRecordDecl *D = cast<CXXRecordDecl>(GetDecl(Record[0]));
+    QualType TST = GetType(Record[1]); // probably derivable
+    // FIXME: ASTContext::getInjectedClassNameType is not currently suitable
+    // for AST reading, too much interdependencies.
+    return
+      QualType(new (*Context, TypeAlignment) InjectedClassNameType(D, TST), 0);
+  }
+  
+  case TYPE_TEMPLATE_TYPE_PARM: {
+    unsigned Idx = 0;
+    unsigned Depth = Record[Idx++];
+    unsigned Index = Record[Idx++];
+    bool Pack = Record[Idx++];
+    IdentifierInfo *Name = GetIdentifierInfo(Record, Idx);
+    return Context->getTemplateTypeParmType(Depth, Index, Pack, Name);
+  }
+  
+  case TYPE_DEPENDENT_NAME: {
+    unsigned Idx = 0;
+    ElaboratedTypeKeyword Keyword = (ElaboratedTypeKeyword)Record[Idx++];
+    NestedNameSpecifier *NNS = ReadNestedNameSpecifier(Record, Idx);
+    const IdentifierInfo *Name = this->GetIdentifierInfo(Record, Idx);
+    QualType Canon = GetType(Record[Idx++]);
+    return Context->getDependentNameType(Keyword, NNS, Name, Canon);
+  }
+  
+  case TYPE_DEPENDENT_TEMPLATE_SPECIALIZATION: {
+    unsigned Idx = 0;
+    ElaboratedTypeKeyword Keyword = (ElaboratedTypeKeyword)Record[Idx++];
+    NestedNameSpecifier *NNS = ReadNestedNameSpecifier(Record, Idx);
+    const IdentifierInfo *Name = this->GetIdentifierInfo(Record, Idx);
+    unsigned NumArgs = Record[Idx++];
+    llvm::SmallVector<TemplateArgument, 8> Args;
+    Args.reserve(NumArgs);
+    while (NumArgs--)
+      Args.push_back(ReadTemplateArgument(DeclsCursor, Record, Idx));
+    return Context->getDependentTemplateSpecializationType(Keyword, NNS, Name,
+                                                      Args.size(), Args.data());
+  }
+  
+  case TYPE_DEPENDENT_SIZED_ARRAY: {
+    unsigned Idx = 0;
+
+    // ArrayType
+    QualType ElementType = GetType(Record[Idx++]);
+    ArrayType::ArraySizeModifier ASM
+      = (ArrayType::ArraySizeModifier)Record[Idx++];
+    unsigned IndexTypeQuals = Record[Idx++];
+
+    // DependentSizedArrayType
+    Expr *NumElts = ReadExpr(DeclsCursor);
+    SourceRange Brackets = ReadSourceRange(Record, Idx);
+
+    return Context->getDependentSizedArrayType(ElementType, NumElts, ASM,
+                                               IndexTypeQuals, Brackets);
+  }
+
+  case TYPE_TEMPLATE_SPECIALIZATION: {
+    unsigned Idx = 0;
+    bool IsDependent = Record[Idx++];
+    TemplateName Name = ReadTemplateName(Record, Idx);
+    llvm::SmallVector<TemplateArgument, 8> Args;
+    ReadTemplateArgumentList(Args, DeclsCursor, Record, Idx);
+    QualType Canon = GetType(Record[Idx++]);
+    QualType T;
+    if (Canon.isNull())
+      T = Context->getCanonicalTemplateSpecializationType(Name, Args.data(),
+                                                          Args.size());
+    else
+      T = Context->getTemplateSpecializationType(Name, Args.data(),
+                                                 Args.size(), Canon);
+    T->Dependent = IsDependent;
+    return T;
+  }
+  }
+  // Suppress a GCC warning
+  return QualType();
+}
+
+namespace {
+
+class TypeLocReader : public TypeLocVisitor<TypeLocReader> {
+  ASTReader &Reader;
+  llvm::BitstreamCursor &DeclsCursor;
+  const ASTReader::RecordData &Record;
+  unsigned &Idx;
+
+public:
+  TypeLocReader(ASTReader &Reader, llvm::BitstreamCursor &Cursor,
+                const ASTReader::RecordData &Record, unsigned &Idx)
+    : Reader(Reader), DeclsCursor(Cursor), 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
+  // define them out-of-line.
+#define ABSTRACT_TYPELOC(CLASS, PARENT)
+#define TYPELOC(CLASS, PARENT) \
+  void Visit##CLASS##TypeLoc(CLASS##TypeLoc TyLoc);
+#include "clang/AST/TypeLocNodes.def"
+
+  void VisitFunctionTypeLoc(FunctionTypeLoc);
+  void VisitArrayTypeLoc(ArrayTypeLoc);
+};
+
+}
+
+void TypeLocReader::VisitQualifiedTypeLoc(QualifiedTypeLoc TL) {
+  // nothing to do
+}
+void TypeLocReader::VisitBuiltinTypeLoc(BuiltinTypeLoc TL) {
+  TL.setBuiltinLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  if (TL.needsExtraLocalData()) {
+    TL.setWrittenTypeSpec(static_cast<DeclSpec::TST>(Record[Idx++]));
+    TL.setWrittenSignSpec(static_cast<DeclSpec::TSS>(Record[Idx++]));
+    TL.setWrittenWidthSpec(static_cast<DeclSpec::TSW>(Record[Idx++]));
+    TL.setModeAttr(Record[Idx++]);
+  }
+}
+void TypeLocReader::VisitComplexTypeLoc(ComplexTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitPointerTypeLoc(PointerTypeLoc TL) {
+  TL.setStarLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitBlockPointerTypeLoc(BlockPointerTypeLoc TL) {
+  TL.setCaretLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitLValueReferenceTypeLoc(LValueReferenceTypeLoc TL) {
+  TL.setAmpLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitRValueReferenceTypeLoc(RValueReferenceTypeLoc TL) {
+  TL.setAmpAmpLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitMemberPointerTypeLoc(MemberPointerTypeLoc TL) {
+  TL.setStarLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitArrayTypeLoc(ArrayTypeLoc TL) {
+  TL.setLBracketLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setRBracketLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  if (Record[Idx++])
+    TL.setSizeExpr(Reader.ReadExpr(DeclsCursor));
+  else
+    TL.setSizeExpr(0);
+}
+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(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitVectorTypeLoc(VectorTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitExtVectorTypeLoc(ExtVectorTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitFunctionTypeLoc(FunctionTypeLoc TL) {
+  TL.setLParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i) {
+    TL.setArg(i, cast_or_null<ParmVarDecl>(Reader.GetDecl(Record[Idx++])));
+  }
+}
+void TypeLocReader::VisitFunctionProtoTypeLoc(FunctionProtoTypeLoc TL) {
+  VisitFunctionTypeLoc(TL);
+}
+void TypeLocReader::VisitFunctionNoProtoTypeLoc(FunctionNoProtoTypeLoc TL) {
+  VisitFunctionTypeLoc(TL);
+}
+void TypeLocReader::VisitUnresolvedUsingTypeLoc(UnresolvedUsingTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitTypedefTypeLoc(TypedefTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitTypeOfExprTypeLoc(TypeOfExprTypeLoc TL) {
+  TL.setTypeofLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setLParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitTypeOfTypeLoc(TypeOfTypeLoc TL) {
+  TL.setTypeofLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setLParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setUnderlyingTInfo(Reader.GetTypeSourceInfo(DeclsCursor, Record, Idx));
+}
+void TypeLocReader::VisitDecltypeTypeLoc(DecltypeTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitRecordTypeLoc(RecordTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitEnumTypeLoc(EnumTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitTemplateTypeParmTypeLoc(TemplateTypeParmTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitSubstTemplateTypeParmTypeLoc(
+                                            SubstTemplateTypeParmTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitTemplateSpecializationTypeLoc(
+                                           TemplateSpecializationTypeLoc TL) {
+  TL.setTemplateNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setLAngleLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setRAngleLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  for (unsigned i = 0, e = TL.getNumArgs(); i != e; ++i)
+    TL.setArgLocInfo(i,
+        Reader.GetTemplateArgumentLocInfo(TL.getTypePtr()->getArg(i).getKind(),
+                                          DeclsCursor, Record, Idx));
+}
+void TypeLocReader::VisitElaboratedTypeLoc(ElaboratedTypeLoc TL) {
+  TL.setKeywordLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setQualifierRange(Reader.ReadSourceRange(Record, Idx));
+}
+void TypeLocReader::VisitInjectedClassNameTypeLoc(InjectedClassNameTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitDependentNameTypeLoc(DependentNameTypeLoc TL) {
+  TL.setKeywordLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setQualifierRange(Reader.ReadSourceRange(Record, Idx));
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitDependentTemplateSpecializationTypeLoc(
+       DependentTemplateSpecializationTypeLoc TL) {
+  TL.setKeywordLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setQualifierRange(Reader.ReadSourceRange(Record, Idx));
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setLAngleLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setRAngleLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I)
+    TL.setArgLocInfo(I,
+        Reader.GetTemplateArgumentLocInfo(TL.getTypePtr()->getArg(I).getKind(),
+                                          DeclsCursor, Record, Idx));
+}
+void TypeLocReader::VisitObjCInterfaceTypeLoc(ObjCInterfaceTypeLoc TL) {
+  TL.setNameLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitObjCObjectTypeLoc(ObjCObjectTypeLoc TL) {
+  TL.setHasBaseTypeAsWritten(Record[Idx++]);
+  TL.setLAngleLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  TL.setRAngleLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+  for (unsigned i = 0, e = TL.getNumProtocols(); i != e; ++i)
+    TL.setProtocolLoc(i, SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+void TypeLocReader::VisitObjCObjectPointerTypeLoc(ObjCObjectPointerTypeLoc TL) {
+  TL.setStarLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
+}
+
+TypeSourceInfo *ASTReader::GetTypeSourceInfo(llvm::BitstreamCursor &DeclsCursor,
+                                             const RecordData &Record,
+                                             unsigned &Idx) {
+  QualType InfoTy = GetType(Record[Idx++]);
+  if (InfoTy.isNull())
+    return 0;
+
+  TypeSourceInfo *TInfo = getContext()->CreateTypeSourceInfo(InfoTy);
+  TypeLocReader TLR(*this, DeclsCursor, Record, Idx);
+  for (TypeLoc TL = TInfo->getTypeLoc(); !TL.isNull(); TL = TL.getNextTypeLoc())
+    TLR.Visit(TL);
+  return TInfo;
+}
+
+QualType ASTReader::GetType(TypeID ID) {
+  unsigned FastQuals = ID & Qualifiers::FastMask;
+  unsigned Index = ID >> Qualifiers::FastWidth;
+
+  if (Index < NUM_PREDEF_TYPE_IDS) {
+    QualType T;
+    switch ((PredefinedTypeIDs)Index) {
+    case PREDEF_TYPE_NULL_ID: return QualType();
+    case PREDEF_TYPE_VOID_ID: T = Context->VoidTy; break;
+    case PREDEF_TYPE_BOOL_ID: T = Context->BoolTy; break;
+
+    case PREDEF_TYPE_CHAR_U_ID:
+    case PREDEF_TYPE_CHAR_S_ID:
+      // FIXME: Check that the signedness of CharTy is correct!
+      T = Context->CharTy;
+      break;
+
+    case PREDEF_TYPE_UCHAR_ID:      T = Context->UnsignedCharTy;     break;
+    case PREDEF_TYPE_USHORT_ID:     T = Context->UnsignedShortTy;    break;
+    case PREDEF_TYPE_UINT_ID:       T = Context->UnsignedIntTy;      break;
+    case PREDEF_TYPE_ULONG_ID:      T = Context->UnsignedLongTy;     break;
+    case PREDEF_TYPE_ULONGLONG_ID:  T = Context->UnsignedLongLongTy; break;
+    case PREDEF_TYPE_UINT128_ID:    T = Context->UnsignedInt128Ty;   break;
+    case PREDEF_TYPE_SCHAR_ID:      T = Context->SignedCharTy;       break;
+    case PREDEF_TYPE_WCHAR_ID:      T = Context->WCharTy;            break;
+    case PREDEF_TYPE_SHORT_ID:      T = Context->ShortTy;            break;
+    case PREDEF_TYPE_INT_ID:        T = Context->IntTy;              break;
+    case PREDEF_TYPE_LONG_ID:       T = Context->LongTy;             break;
+    case PREDEF_TYPE_LONGLONG_ID:   T = Context->LongLongTy;         break;
+    case PREDEF_TYPE_INT128_ID:     T = Context->Int128Ty;           break;
+    case PREDEF_TYPE_FLOAT_ID:      T = Context->FloatTy;            break;
+    case PREDEF_TYPE_DOUBLE_ID:     T = Context->DoubleTy;           break;
+    case PREDEF_TYPE_LONGDOUBLE_ID: T = Context->LongDoubleTy;       break;
+    case PREDEF_TYPE_OVERLOAD_ID:   T = Context->OverloadTy;         break;
+    case PREDEF_TYPE_DEPENDENT_ID:  T = Context->DependentTy;        break;
+    case PREDEF_TYPE_NULLPTR_ID:    T = Context->NullPtrTy;          break;
+    case PREDEF_TYPE_CHAR16_ID:     T = Context->Char16Ty;           break;
+    case PREDEF_TYPE_CHAR32_ID:     T = Context->Char32Ty;           break;
+    case PREDEF_TYPE_OBJC_ID:       T = Context->ObjCBuiltinIdTy;    break;
+    case PREDEF_TYPE_OBJC_CLASS:    T = Context->ObjCBuiltinClassTy; break;
+    case PREDEF_TYPE_OBJC_SEL:      T = Context->ObjCBuiltinSelTy;   break;
+    }
+
+    assert(!T.isNull() && "Unknown predefined type");
+    return T.withFastQualifiers(FastQuals);
+  }
+
+  Index -= NUM_PREDEF_TYPE_IDS;
+  assert(Index < TypesLoaded.size() && "Type index out-of-range");
+  if (TypesLoaded[Index].isNull()) {
+    TypesLoaded[Index] = ReadTypeRecord(Index);
+    TypesLoaded[Index]->setFromAST();
+    TypeIdxs[TypesLoaded[Index]] = TypeIdx::fromTypeID(ID);
+    if (DeserializationListener)
+      DeserializationListener->TypeRead(TypeIdx::fromTypeID(ID),
+                                        TypesLoaded[Index]);
+  }
+
+  return TypesLoaded[Index].withFastQualifiers(FastQuals);
+}
+
+TypeID ASTReader::GetTypeID(QualType T) const {
+  return MakeTypeID(T,
+              std::bind1st(std::mem_fun(&ASTReader::GetTypeIdx), this));
+}
+
+TypeIdx ASTReader::GetTypeIdx(QualType T) const {
+  if (T.isNull())
+    return TypeIdx();
+  assert(!T.getLocalFastQualifiers());
+
+  TypeIdxMap::const_iterator I = TypeIdxs.find(T);
+  // GetTypeIdx is mostly used for computing the hash of DeclarationNames and
+  // comparing keys of ASTDeclContextNameLookupTable.
+  // If the type didn't come from the AST file use a specially marked index
+  // so that any hash/key comparison fail since no such index is stored
+  // in a AST file.
+  if (I == TypeIdxs.end())
+    return TypeIdx(-1);
+  return I->second;
+}
+
+TemplateArgumentLocInfo
+ASTReader::GetTemplateArgumentLocInfo(TemplateArgument::ArgKind Kind,
+                                      llvm::BitstreamCursor &DeclsCursor,
+                                      const RecordData &Record,
+                                      unsigned &Index) {
+  switch (Kind) {
+  case TemplateArgument::Expression:
+    return ReadExpr(DeclsCursor);
+  case TemplateArgument::Type:
+    return GetTypeSourceInfo(DeclsCursor, Record, Index);
+  case TemplateArgument::Template: {
+    SourceRange QualifierRange = ReadSourceRange(Record, Index);
+    SourceLocation TemplateNameLoc = ReadSourceLocation(Record, Index);
+    return TemplateArgumentLocInfo(QualifierRange, TemplateNameLoc);
+  }
+  case TemplateArgument::Null:
+  case TemplateArgument::Integral:
+  case TemplateArgument::Declaration:
+  case TemplateArgument::Pack:
+    return TemplateArgumentLocInfo();
+  }
+  llvm_unreachable("unexpected template argument loc");
+  return TemplateArgumentLocInfo();
+}
+
+TemplateArgumentLoc
+ASTReader::ReadTemplateArgumentLoc(llvm::BitstreamCursor &DeclsCursor,
+                                   const RecordData &Record, unsigned &Index) {
+  TemplateArgument Arg = ReadTemplateArgument(DeclsCursor, Record, Index);
+
+  if (Arg.getKind() == TemplateArgument::Expression) {
+    if (Record[Index++]) // bool InfoHasSameExpr.
+      return TemplateArgumentLoc(Arg, TemplateArgumentLocInfo(Arg.getAsExpr()));
+  }
+  return TemplateArgumentLoc(Arg, GetTemplateArgumentLocInfo(Arg.getKind(),
+                                                             DeclsCursor,
+                                                             Record, Index));
+}
+
+Decl *ASTReader::GetExternalDecl(uint32_t ID) {
+  return GetDecl(ID);
+}
+
+TranslationUnitDecl *ASTReader::GetTranslationUnitDecl() {
+  if (!DeclsLoaded[0]) {
+    ReadDeclRecord(0, 1);
+    if (DeserializationListener)
+      DeserializationListener->DeclRead(1, DeclsLoaded[0]);
+  }
+
+  return cast<TranslationUnitDecl>(DeclsLoaded[0]);
+}
+
+Decl *ASTReader::GetDecl(DeclID ID) {
+  if (ID == 0)
+    return 0;
+
+  if (ID > DeclsLoaded.size()) {
+    Error("declaration ID out-of-range for AST file");
+    return 0;
+  }
+
+  unsigned Index = ID - 1;
+  if (!DeclsLoaded[Index]) {
+    ReadDeclRecord(Index, ID);
+    if (DeserializationListener)
+      DeserializationListener->DeclRead(ID, DeclsLoaded[Index]);
+  }
+
+  return DeclsLoaded[Index];
+}
+
+/// \brief Resolve the offset of a statement into a statement.
+///
+/// This operation will read a new statement from the external
+/// source each time it is called, and is meant to be used via a
+/// LazyOffsetPtr (which is used by Decls for the body of functions, etc).
+Stmt *ASTReader::GetExternalDeclStmt(uint64_t Offset) {
+  // Offset here is a global offset across the entire chain.
+  for (unsigned I = 0, N = Chain.size(); I != N; ++I) {
+    PerFileData &F = *Chain[N - I - 1];
+    if (Offset < F.SizeInBits) {
+      // Since we know that this statement is part of a decl, make sure to use
+      // the decl cursor to read it.
+      F.DeclsCursor.JumpToBit(Offset);
+      return ReadStmtFromStream(F.DeclsCursor);
+    }
+    Offset -= F.SizeInBits;
+  }
+  llvm_unreachable("Broken chain");
+}
+
+bool ASTReader::FindExternalLexicalDecls(const DeclContext *DC,
+                                         llvm::SmallVectorImpl<Decl*> &Decls) {
+  assert(DC->hasExternalLexicalStorage() &&
+         "DeclContext has no lexical decls in storage");
+
+  // There might be lexical decls in multiple parts of the chain, for the TU
+  // at least.
+  DeclContextInfos &Infos = DeclContextOffsets[DC];
+  for (DeclContextInfos::iterator I = Infos.begin(), E = Infos.end();
+       I != E; ++I) {
+    // IDs can be 0 if this context doesn't contain declarations.
+    if (!I->LexicalDecls)
+      continue;
+
+    // Load all of the declaration IDs
+    for (const DeclID *ID = I->LexicalDecls,
+                           *IDE = ID + I->NumLexicalDecls;
+         ID != IDE; ++ID)
+      Decls.push_back(GetDecl(*ID));
+  }
+
+  ++NumLexicalDeclContextsRead;
+  return false;
+}
+
+DeclContext::lookup_result
+ASTReader::FindExternalVisibleDeclsByName(const DeclContext *DC,
+                                          DeclarationName Name) {
+  assert(DC->hasExternalVisibleStorage() &&
+         "DeclContext has no visible decls in storage");
+  if (!Name)
+    return DeclContext::lookup_result(DeclContext::lookup_iterator(0),
+                                      DeclContext::lookup_iterator(0));
+
+  llvm::SmallVector<NamedDecl *, 64> Decls;
+  // There might be visible decls in multiple parts of the chain, for the TU
+  // and namespaces. For any given name, the last available results replace
+  // all earlier ones. For this reason, we walk in reverse.
+  DeclContextInfos &Infos = DeclContextOffsets[DC];
+  for (DeclContextInfos::reverse_iterator I = Infos.rbegin(), E = Infos.rend();
+       I != E; ++I) {
+    if (!I->NameLookupTableData)
+      continue;
+
+    ASTDeclContextNameLookupTable *LookupTable =
+        (ASTDeclContextNameLookupTable*)I->NameLookupTableData;
+    ASTDeclContextNameLookupTable::iterator Pos = LookupTable->find(Name);
+    if (Pos == LookupTable->end())
+      continue;
+
+    ASTDeclContextNameLookupTrait::data_type Data = *Pos;
+    for (; Data.first != Data.second; ++Data.first)
+      Decls.push_back(cast<NamedDecl>(GetDecl(*Data.first)));
+    break;
+  }
+
+  ++NumVisibleDeclContextsRead;
+
+  SetExternalVisibleDeclsForName(DC, Name, Decls);
+  return const_cast<DeclContext*>(DC)->lookup(Name);
+}
+
+void ASTReader::MaterializeVisibleDecls(const DeclContext *DC) {
+  assert(DC->hasExternalVisibleStorage() &&
+         "DeclContext has no visible decls in storage");
+
+  llvm::SmallVector<NamedDecl *, 64> Decls;
+  // There might be visible decls in multiple parts of the chain, for the TU
+  // and namespaces.
+  DeclContextInfos &Infos = DeclContextOffsets[DC];
+  for (DeclContextInfos::iterator I = Infos.begin(), E = Infos.end();
+       I != E; ++I) {
+    if (!I->NameLookupTableData)
+      continue;
+
+    ASTDeclContextNameLookupTable *LookupTable =
+        (ASTDeclContextNameLookupTable*)I->NameLookupTableData;
+    for (ASTDeclContextNameLookupTable::item_iterator
+           ItemI = LookupTable->item_begin(),
+           ItemEnd = LookupTable->item_end() ; ItemI != ItemEnd; ++ItemI) {
+      ASTDeclContextNameLookupTable::item_iterator::value_type Val
+          = *ItemI;
+      ASTDeclContextNameLookupTrait::data_type Data = Val.second;
+      Decls.clear();
+      for (; Data.first != Data.second; ++Data.first)
+        Decls.push_back(cast<NamedDecl>(GetDecl(*Data.first)));
+      MaterializeVisibleDeclsForName(DC, Val.first, Decls);
+    }
+  }
+}
+
+void ASTReader::PassInterestingDeclsToConsumer() {
+  assert(Consumer);
+  while (!InterestingDecls.empty()) {
+    DeclGroupRef DG(InterestingDecls.front());
+    InterestingDecls.pop_front();
+    Consumer->HandleInterestingDecl(DG);
+  }
+}
+
+void ASTReader::StartTranslationUnit(ASTConsumer *Consumer) {
+  this->Consumer = Consumer;
+
+  if (!Consumer)
+    return;
+
+  for (unsigned I = 0, N = ExternalDefinitions.size(); I != N; ++I) {
+    // Force deserialization of this decl, which will cause it to be queued for
+    // passing to the consumer.
+    GetDecl(ExternalDefinitions[I]);
+  }
+
+  PassInterestingDeclsToConsumer();
+}
+
+void ASTReader::PrintStats() {
+  std::fprintf(stderr, "*** AST File Statistics:\n");
+
+  unsigned NumTypesLoaded
+    = TypesLoaded.size() - std::count(TypesLoaded.begin(), TypesLoaded.end(),
+                                      QualType());
+  unsigned NumDeclsLoaded
+    = DeclsLoaded.size() - std::count(DeclsLoaded.begin(), DeclsLoaded.end(),
+                                      (Decl *)0);
+  unsigned NumIdentifiersLoaded
+    = IdentifiersLoaded.size() - std::count(IdentifiersLoaded.begin(),
+                                            IdentifiersLoaded.end(),
+                                            (IdentifierInfo *)0);
+  unsigned NumSelectorsLoaded
+    = SelectorsLoaded.size() - std::count(SelectorsLoaded.begin(),
+                                          SelectorsLoaded.end(),
+                                          Selector());
+
+  std::fprintf(stderr, "  %u stat cache hits\n", NumStatHits);
+  std::fprintf(stderr, "  %u stat cache misses\n", NumStatMisses);
+  if (TotalNumSLocEntries)
+    std::fprintf(stderr, "  %u/%u source location entries read (%f%%)\n",
+                 NumSLocEntriesRead, TotalNumSLocEntries,
+                 ((float)NumSLocEntriesRead/TotalNumSLocEntries * 100));
+  if (!TypesLoaded.empty())
+    std::fprintf(stderr, "  %u/%u types read (%f%%)\n",
+                 NumTypesLoaded, (unsigned)TypesLoaded.size(),
+                 ((float)NumTypesLoaded/TypesLoaded.size() * 100));
+  if (!DeclsLoaded.empty())
+    std::fprintf(stderr, "  %u/%u declarations read (%f%%)\n",
+                 NumDeclsLoaded, (unsigned)DeclsLoaded.size(),
+                 ((float)NumDeclsLoaded/DeclsLoaded.size() * 100));
+  if (!IdentifiersLoaded.empty())
+    std::fprintf(stderr, "  %u/%u identifiers read (%f%%)\n",
+                 NumIdentifiersLoaded, (unsigned)IdentifiersLoaded.size(),
+                 ((float)NumIdentifiersLoaded/IdentifiersLoaded.size() * 100));
+  if (!SelectorsLoaded.empty())
+    std::fprintf(stderr, "  %u/%u selectors read (%f%%)\n",
+                 NumSelectorsLoaded, (unsigned)SelectorsLoaded.size(),
+                 ((float)NumSelectorsLoaded/SelectorsLoaded.size() * 100));
+  if (TotalNumStatements)
+    std::fprintf(stderr, "  %u/%u statements read (%f%%)\n",
+                 NumStatementsRead, TotalNumStatements,
+                 ((float)NumStatementsRead/TotalNumStatements * 100));
+  if (TotalNumMacros)
+    std::fprintf(stderr, "  %u/%u macros read (%f%%)\n",
+                 NumMacrosRead, TotalNumMacros,
+                 ((float)NumMacrosRead/TotalNumMacros * 100));
+  if (TotalLexicalDeclContexts)
+    std::fprintf(stderr, "  %u/%u lexical declcontexts read (%f%%)\n",
+                 NumLexicalDeclContextsRead, TotalLexicalDeclContexts,
+                 ((float)NumLexicalDeclContextsRead/TotalLexicalDeclContexts
+                  * 100));
+  if (TotalVisibleDeclContexts)
+    std::fprintf(stderr, "  %u/%u visible declcontexts read (%f%%)\n",
+                 NumVisibleDeclContextsRead, TotalVisibleDeclContexts,
+                 ((float)NumVisibleDeclContextsRead/TotalVisibleDeclContexts
+                  * 100));
+  if (TotalNumMethodPoolEntries) {
+    std::fprintf(stderr, "  %u/%u method pool entries read (%f%%)\n",
+                 NumMethodPoolEntriesRead, TotalNumMethodPoolEntries,
+                 ((float)NumMethodPoolEntriesRead/TotalNumMethodPoolEntries
+                  * 100));
+    std::fprintf(stderr, "  %u method pool misses\n", NumMethodPoolMisses);
+  }
+  std::fprintf(stderr, "\n");
+}
+
+void ASTReader::InitializeSema(Sema &S) {
+  SemaObj = &S;
+  S.ExternalSource = this;
+
+  // Makes sure any declarations that were deserialized "too early"
+  // still get added to the identifier's declaration chains.
+  if (SemaObj->TUScope) {
+    for (unsigned I = 0, N = PreloadedDecls.size(); I != N; ++I) {
+      SemaObj->TUScope->AddDecl(PreloadedDecls[I]);
+      SemaObj->IdResolver.AddDecl(PreloadedDecls[I]);
+    }
+  }
+  PreloadedDecls.clear();
+
+  // If there were any tentative definitions, deserialize them and add
+  // them to Sema's list of tentative definitions.
+  for (unsigned I = 0, N = TentativeDefinitions.size(); I != N; ++I) {
+    VarDecl *Var = cast<VarDecl>(GetDecl(TentativeDefinitions[I]));
+    SemaObj->TentativeDefinitions.push_back(Var);
+  }
+
+  // If there were any unused file scoped decls, deserialize them and add to
+  // Sema's list of unused file scoped decls.
+  for (unsigned I = 0, N = UnusedFileScopedDecls.size(); I != N; ++I) {
+    DeclaratorDecl *D = cast<DeclaratorDecl>(GetDecl(UnusedFileScopedDecls[I]));
+    SemaObj->UnusedFileScopedDecls.push_back(D);
+  }
+
+  // If there were any weak undeclared identifiers, deserialize them and add to
+  // Sema's list of weak undeclared identifiers.
+  if (!WeakUndeclaredIdentifiers.empty()) {
+    unsigned Idx = 0;
+    for (unsigned I = 0, N = WeakUndeclaredIdentifiers[Idx++]; I != N; ++I) {
+      IdentifierInfo *WeakId = GetIdentifierInfo(WeakUndeclaredIdentifiers,Idx);
+      IdentifierInfo *AliasId=GetIdentifierInfo(WeakUndeclaredIdentifiers,Idx);
+      SourceLocation Loc = ReadSourceLocation(WeakUndeclaredIdentifiers, Idx);
+      bool Used = WeakUndeclaredIdentifiers[Idx++];
+      Sema::WeakInfo WI(AliasId, Loc);
+      WI.setUsed(Used);
+      SemaObj->WeakUndeclaredIdentifiers.insert(std::make_pair(WeakId, WI));
+    }
+  }
+
+  // If there were any locally-scoped external declarations,
+  // deserialize them and add them to Sema's table of locally-scoped
+  // external declarations.
+  for (unsigned I = 0, N = LocallyScopedExternalDecls.size(); I != N; ++I) {
+    NamedDecl *D = cast<NamedDecl>(GetDecl(LocallyScopedExternalDecls[I]));
+    SemaObj->LocallyScopedExternalDecls[D->getDeclName()] = D;
+  }
+
+  // If there were any ext_vector type declarations, deserialize them
+  // and add them to Sema's vector of such declarations.
+  for (unsigned I = 0, N = ExtVectorDecls.size(); I != N; ++I)
+    SemaObj->ExtVectorDecls.push_back(
+                               cast<TypedefDecl>(GetDecl(ExtVectorDecls[I])));
+
+  // FIXME: Do VTable uses and dynamic classes deserialize too much ?
+  // Can we cut them down before writing them ?
+
+  // If there were any VTable uses, deserialize the information and add it
+  // to Sema's vector and map of VTable uses.
+  if (!VTableUses.empty()) {
+    unsigned Idx = 0;
+    for (unsigned I = 0, N = VTableUses[Idx++]; I != N; ++I) {
+      CXXRecordDecl *Class = cast<CXXRecordDecl>(GetDecl(VTableUses[Idx++]));
+      SourceLocation Loc = ReadSourceLocation(VTableUses, Idx);
+      bool DefinitionRequired = VTableUses[Idx++];
+      SemaObj->VTableUses.push_back(std::make_pair(Class, Loc));
+      SemaObj->VTablesUsed[Class] = DefinitionRequired;
+    }
+  }
+
+  // If there were any dynamic classes declarations, deserialize them
+  // and add them to Sema's vector of such declarations.
+  for (unsigned I = 0, N = DynamicClasses.size(); I != N; ++I)
+    SemaObj->DynamicClasses.push_back(
+                               cast<CXXRecordDecl>(GetDecl(DynamicClasses[I])));
+
+  // If there were any pending implicit instantiations, deserialize them
+  // and add them to Sema's queue of such instantiations.
+  assert(PendingInstantiations.size() % 2 == 0 && "Expected pairs of entries");
+  for (unsigned Idx = 0, N = PendingInstantiations.size(); Idx < N;) {
+    ValueDecl *D=cast<ValueDecl>(GetDecl(PendingInstantiations[Idx++]));
+    SourceLocation Loc = ReadSourceLocation(PendingInstantiations, Idx);
+    SemaObj->PendingInstantiations.push_back(std::make_pair(D, Loc));
+  }
+
+  // Load the offsets of the declarations that Sema references.
+  // They will be lazily deserialized when needed.
+  if (!SemaDeclRefs.empty()) {
+    assert(SemaDeclRefs.size() == 2 && "More decl refs than expected!");
+    SemaObj->StdNamespace = SemaDeclRefs[0];
+    SemaObj->StdBadAlloc = SemaDeclRefs[1];
+  }
+
+  // If there are @selector references added them to its pool. This is for
+  // implementation of -Wselector.
+  if (!ReferencedSelectorsData.empty()) {
+    unsigned int DataSize = ReferencedSelectorsData.size()-1;
+    unsigned I = 0;
+    while (I < DataSize) {
+      Selector Sel = DecodeSelector(ReferencedSelectorsData[I++]);
+      SourceLocation SelLoc = 
+        SourceLocation::getFromRawEncoding(ReferencedSelectorsData[I++]);
+      SemaObj->ReferencedSelectors.insert(std::make_pair(Sel, SelLoc));
+    }
+  }
+}
+
+IdentifierInfo* ASTReader::get(const char *NameStart, const char *NameEnd) {
+  // Try to find this name within our on-disk hash tables. We start with the
+  // most recent one, since that one contains the most up-to-date info.
+  for (unsigned I = 0, N = Chain.size(); I != N; ++I) {
+    ASTIdentifierLookupTable *IdTable
+        = (ASTIdentifierLookupTable *)Chain[I]->IdentifierLookupTable;
+    if (!IdTable)
+      continue;
+    std::pair<const char*, unsigned> Key(NameStart, NameEnd - NameStart);
+    ASTIdentifierLookupTable::iterator Pos = IdTable->find(Key);
+    if (Pos == IdTable->end())
+      continue;
+
+    // Dereferencing the iterator has the effect of building the
+    // IdentifierInfo node and populating it with the various
+    // declarations it needs.
+    return *Pos;
+  }
+  return 0;
+}
+
+std::pair<ObjCMethodList, ObjCMethodList>
+ASTReader::ReadMethodPool(Selector Sel) {
+  // Find this selector in a hash table. We want to find the most recent entry.
+  for (unsigned I = 0, N = Chain.size(); I != N; ++I) {
+    PerFileData &F = *Chain[I];
+    if (!F.SelectorLookupTable)
+      continue;
+
+    ASTSelectorLookupTable *PoolTable
+      = (ASTSelectorLookupTable*)F.SelectorLookupTable;
+    ASTSelectorLookupTable::iterator Pos = PoolTable->find(Sel);
+    if (Pos != PoolTable->end()) {
+      ++NumSelectorsRead;
+      // FIXME: Not quite happy with the statistics here. We probably should
+      // disable this tracking when called via LoadSelector.
+      // Also, should entries without methods count as misses?
+      ++NumMethodPoolEntriesRead;
+      ASTSelectorLookupTrait::data_type Data = *Pos;
+      if (DeserializationListener)
+        DeserializationListener->SelectorRead(Data.ID, Sel);
+      return std::make_pair(Data.Instance, Data.Factory);
+    }
+  }
+
+  ++NumMethodPoolMisses;
+  return std::pair<ObjCMethodList, ObjCMethodList>();
+}
+
+void ASTReader::LoadSelector(Selector Sel) {
+  // It would be complicated to avoid reading the methods anyway. So don't.
+  ReadMethodPool(Sel);
+}
+
+void ASTReader::SetIdentifierInfo(unsigned ID, IdentifierInfo *II) {
+  assert(ID && "Non-zero identifier ID required");
+  assert(ID <= IdentifiersLoaded.size() && "identifier ID out of range");
+  IdentifiersLoaded[ID - 1] = II;
+  if (DeserializationListener)
+    DeserializationListener->IdentifierRead(ID, II);
+}
+
+/// \brief Set the globally-visible declarations associated with the given
+/// identifier.
+///
+/// If the AST reader is currently in a state where the given declaration IDs
+/// cannot safely be resolved, they are queued until it is safe to resolve
+/// them.
+///
+/// \param II an IdentifierInfo that refers to one or more globally-visible
+/// declarations.
+///
+/// \param DeclIDs the set of declaration IDs with the name @p II that are
+/// visible at global scope.
+///
+/// \param Nonrecursive should be true to indicate that the caller knows that
+/// this call is non-recursive, and therefore the globally-visible declarations
+/// will not be placed onto the pending queue.
+void
+ASTReader::SetGloballyVisibleDecls(IdentifierInfo *II,
+                              const llvm::SmallVectorImpl<uint32_t> &DeclIDs,
+                                   bool Nonrecursive) {
+  if (NumCurrentElementsDeserializing && !Nonrecursive) {
+    PendingIdentifierInfos.push_back(PendingIdentifierInfo());
+    PendingIdentifierInfo &PII = PendingIdentifierInfos.back();
+    PII.II = II;
+    for (unsigned I = 0, N = DeclIDs.size(); I != N; ++I)
+      PII.DeclIDs.push_back(DeclIDs[I]);
+    return;
+  }
+
+  for (unsigned I = 0, N = DeclIDs.size(); I != N; ++I) {
+    NamedDecl *D = cast<NamedDecl>(GetDecl(DeclIDs[I]));
+    if (SemaObj) {
+      if (SemaObj->TUScope) {
+        // Introduce this declaration into the translation-unit scope
+        // and add it to the declaration chain for this identifier, so
+        // that (unqualified) name lookup will find it.
+        SemaObj->TUScope->AddDecl(D);
+        SemaObj->IdResolver.AddDeclToIdentifierChain(II, D);
+      }
+    } else {
+      // Queue this declaration so that it will be added to the
+      // translation unit scope and identifier's declaration chain
+      // once a Sema object is known.
+      PreloadedDecls.push_back(D);
+    }
+  }
+}
+
+IdentifierInfo *ASTReader::DecodeIdentifierInfo(unsigned ID) {
+  if (ID == 0)
+    return 0;
+
+  if (IdentifiersLoaded.empty()) {
+    Error("no identifier table in AST file");
+    return 0;
+  }
+
+  assert(PP && "Forgot to set Preprocessor ?");
+  ID -= 1;
+  if (!IdentifiersLoaded[ID]) {
+    unsigned Index = ID;
+    const char *Str = 0;
+    for (unsigned I = 0, N = Chain.size(); I != N; ++I) {
+      PerFileData *F = Chain[N - I - 1];
+      if (Index < F->LocalNumIdentifiers) {
+         uint32_t Offset = F->IdentifierOffsets[Index];
+         Str = F->IdentifierTableData + Offset;
+         break;
+      }
+      Index -= F->LocalNumIdentifiers;
+    }
+    assert(Str && "Broken Chain");
+
+    // All of the strings in the AST file are preceded by a 16-bit length.
+    // Extract that 16-bit length to avoid having to execute strlen().
+    // NOTE: 'StrLenPtr' is an 'unsigned char*' so that we load bytes as
+    //  unsigned integers.  This is important to avoid integer overflow when
+    //  we cast them to 'unsigned'.
+    const unsigned char *StrLenPtr = (const unsigned char*) Str - 2;
+    unsigned StrLen = (((unsigned) StrLenPtr[0])
+                       | (((unsigned) StrLenPtr[1]) << 8)) - 1;
+    IdentifiersLoaded[ID]
+      = &PP->getIdentifierTable().get(Str, StrLen);
+    if (DeserializationListener)
+      DeserializationListener->IdentifierRead(ID + 1, IdentifiersLoaded[ID]);
+  }
+
+  return IdentifiersLoaded[ID];
+}
+
+void ASTReader::ReadSLocEntry(unsigned ID) {
+  ReadSLocEntryRecord(ID);
+}
+
+Selector ASTReader::DecodeSelector(unsigned ID) {
+  if (ID == 0)
+    return Selector();
+
+  if (ID > SelectorsLoaded.size()) {
+    Error("selector ID out of range in AST file");
+    return Selector();
+  }
+
+  if (SelectorsLoaded[ID - 1].getAsOpaquePtr() == 0) {
+    // Load this selector from the selector table.
+    unsigned Idx = ID - 1;
+    for (unsigned I = 0, N = Chain.size(); I != N; ++I) {
+      PerFileData &F = *Chain[N - I - 1];
+      if (Idx < F.LocalNumSelectors) {
+        ASTSelectorLookupTrait Trait(*this);
+        SelectorsLoaded[ID - 1] =
+           Trait.ReadKey(F.SelectorLookupTableData + F.SelectorOffsets[Idx], 0);
+        if (DeserializationListener)
+          DeserializationListener->SelectorRead(ID, SelectorsLoaded[ID - 1]);
+        break;
+      }
+      Idx -= F.LocalNumSelectors;
+    }
+  }
+
+  return SelectorsLoaded[ID - 1];
+}
+
+Selector ASTReader::GetExternalSelector(uint32_t ID) { 
+  return DecodeSelector(ID);
+}
+
+uint32_t ASTReader::GetNumExternalSelectors() {
+  // ID 0 (the null selector) is considered an external selector.
+  return getTotalNumSelectors() + 1;
+}
+
+DeclarationName
+ASTReader::ReadDeclarationName(const RecordData &Record, unsigned &Idx) {
+  DeclarationName::NameKind Kind = (DeclarationName::NameKind)Record[Idx++];
+  switch (Kind) {
+  case DeclarationName::Identifier:
+    return DeclarationName(GetIdentifierInfo(Record, Idx));
+
+  case DeclarationName::ObjCZeroArgSelector:
+  case DeclarationName::ObjCOneArgSelector:
+  case DeclarationName::ObjCMultiArgSelector:
+    return DeclarationName(GetSelector(Record, Idx));
+
+  case DeclarationName::CXXConstructorName:
+    return Context->DeclarationNames.getCXXConstructorName(
+                          Context->getCanonicalType(GetType(Record[Idx++])));
+
+  case DeclarationName::CXXDestructorName:
+    return Context->DeclarationNames.getCXXDestructorName(
+                          Context->getCanonicalType(GetType(Record[Idx++])));
+
+  case DeclarationName::CXXConversionFunctionName:
+    return Context->DeclarationNames.getCXXConversionFunctionName(
+                          Context->getCanonicalType(GetType(Record[Idx++])));
+
+  case DeclarationName::CXXOperatorName:
+    return Context->DeclarationNames.getCXXOperatorName(
+                                       (OverloadedOperatorKind)Record[Idx++]);
+
+  case DeclarationName::CXXLiteralOperatorName:
+    return Context->DeclarationNames.getCXXLiteralOperatorName(
+                                       GetIdentifierInfo(Record, Idx));
+
+  case DeclarationName::CXXUsingDirective:
+    return DeclarationName::getUsingDirectiveName();
+  }
+
+  // Required to silence GCC warning
+  return DeclarationName();
+}
+
+TemplateName
+ASTReader::ReadTemplateName(const RecordData &Record, unsigned &Idx) {
+  TemplateName::NameKind Kind = (TemplateName::NameKind)Record[Idx++]; 
+  switch (Kind) {
+  case TemplateName::Template:
+    return TemplateName(cast_or_null<TemplateDecl>(GetDecl(Record[Idx++])));
+
+  case TemplateName::OverloadedTemplate: {
+    unsigned size = Record[Idx++];
+    UnresolvedSet<8> Decls;
+    while (size--)
+      Decls.addDecl(cast<NamedDecl>(GetDecl(Record[Idx++])));
+
+    return Context->getOverloadedTemplateName(Decls.begin(), Decls.end());
+  }
+    
+  case TemplateName::QualifiedTemplate: {
+    NestedNameSpecifier *NNS = ReadNestedNameSpecifier(Record, Idx);
+    bool hasTemplKeyword = Record[Idx++];
+    TemplateDecl *Template = cast<TemplateDecl>(GetDecl(Record[Idx++]));
+    return Context->getQualifiedTemplateName(NNS, hasTemplKeyword, Template);
+  }
+    
+  case TemplateName::DependentTemplate: {
+    NestedNameSpecifier *NNS = ReadNestedNameSpecifier(Record, Idx);
+    if (Record[Idx++])  // isIdentifier
+      return Context->getDependentTemplateName(NNS,
+                                               GetIdentifierInfo(Record, Idx));
+    return Context->getDependentTemplateName(NNS,
+                                         (OverloadedOperatorKind)Record[Idx++]);
+  }
+  }
+  
+  assert(0 && "Unhandled template name kind!");
+  return TemplateName();
+}
+
+TemplateArgument
+ASTReader::ReadTemplateArgument(llvm::BitstreamCursor &DeclsCursor,
+                                const RecordData &Record, unsigned &Idx) {
+  switch ((TemplateArgument::ArgKind)Record[Idx++]) {
+  case TemplateArgument::Null:
+    return TemplateArgument();
+  case TemplateArgument::Type:
+    return TemplateArgument(GetType(Record[Idx++]));
+  case TemplateArgument::Declaration:
+    return TemplateArgument(GetDecl(Record[Idx++]));
+  case TemplateArgument::Integral: {
+    llvm::APSInt Value = ReadAPSInt(Record, Idx);
+    QualType T = GetType(Record[Idx++]);
+    return TemplateArgument(Value, T);
+  }
+  case TemplateArgument::Template:
+    return TemplateArgument(ReadTemplateName(Record, Idx));
+  case TemplateArgument::Expression:
+    return TemplateArgument(ReadExpr(DeclsCursor));
+  case TemplateArgument::Pack: {
+    unsigned NumArgs = Record[Idx++];
+    llvm::SmallVector<TemplateArgument, 8> Args;
+    Args.reserve(NumArgs);
+    while (NumArgs--)
+      Args.push_back(ReadTemplateArgument(DeclsCursor, Record, Idx));
+    TemplateArgument TemplArg;
+    TemplArg.setArgumentPack(Args.data(), Args.size(), /*CopyArgs=*/true);
+    return TemplArg;
+  }
+  }
+  
+  assert(0 && "Unhandled template argument kind!");
+  return TemplateArgument();
+}
+
+TemplateParameterList *
+ASTReader::ReadTemplateParameterList(const RecordData &Record, unsigned &Idx) {
+  SourceLocation TemplateLoc = ReadSourceLocation(Record, Idx);
+  SourceLocation LAngleLoc = ReadSourceLocation(Record, Idx);
+  SourceLocation RAngleLoc = ReadSourceLocation(Record, Idx);
+
+  unsigned NumParams = Record[Idx++];
+  llvm::SmallVector<NamedDecl *, 16> Params;
+  Params.reserve(NumParams);
+  while (NumParams--)
+    Params.push_back(cast<NamedDecl>(GetDecl(Record[Idx++])));
+    
+  TemplateParameterList* TemplateParams = 
+    TemplateParameterList::Create(*Context, TemplateLoc, LAngleLoc,
+                                  Params.data(), Params.size(), RAngleLoc);
+  return TemplateParams;
+}
+
+void
+ASTReader::
+ReadTemplateArgumentList(llvm::SmallVector<TemplateArgument, 8> &TemplArgs,
+                         llvm::BitstreamCursor &DeclsCursor,
+                         const RecordData &Record, unsigned &Idx) {
+  unsigned NumTemplateArgs = Record[Idx++];
+  TemplArgs.reserve(NumTemplateArgs);
+  while (NumTemplateArgs--)
+    TemplArgs.push_back(ReadTemplateArgument(DeclsCursor, Record, Idx));
+}
+
+/// \brief Read a UnresolvedSet structure.
+void ASTReader::ReadUnresolvedSet(UnresolvedSetImpl &Set,
+                                  const RecordData &Record, unsigned &Idx) {
+  unsigned NumDecls = Record[Idx++];
+  while (NumDecls--) {
+    NamedDecl *D = cast<NamedDecl>(GetDecl(Record[Idx++]));
+    AccessSpecifier AS = (AccessSpecifier)Record[Idx++];
+    Set.addDecl(D, AS);
+  }
+}
+
+CXXBaseSpecifier
+ASTReader::ReadCXXBaseSpecifier(llvm::BitstreamCursor &DeclsCursor,
+                                const RecordData &Record, unsigned &Idx) {
+  bool isVirtual = static_cast<bool>(Record[Idx++]);
+  bool isBaseOfClass = static_cast<bool>(Record[Idx++]);
+  AccessSpecifier AS = static_cast<AccessSpecifier>(Record[Idx++]);
+  TypeSourceInfo *TInfo = GetTypeSourceInfo(DeclsCursor, Record, Idx);
+  SourceRange Range = ReadSourceRange(Record, Idx);
+  return CXXBaseSpecifier(Range, isVirtual, isBaseOfClass, AS, TInfo);
+}
+
+std::pair<CXXBaseOrMemberInitializer **, unsigned>
+ASTReader::ReadCXXBaseOrMemberInitializers(llvm::BitstreamCursor &Cursor,
+                                           const RecordData &Record,
+                                           unsigned &Idx) {
+  CXXBaseOrMemberInitializer **BaseOrMemberInitializers = 0;
+  unsigned NumInitializers = Record[Idx++];
+  if (NumInitializers) {
+    ASTContext &C = *getContext();
+
+    BaseOrMemberInitializers
+        = new (C) CXXBaseOrMemberInitializer*[NumInitializers];
+    for (unsigned i=0; i != NumInitializers; ++i) {
+      TypeSourceInfo *BaseClassInfo = 0;
+      bool IsBaseVirtual = false;
+      FieldDecl *Member = 0;
+  
+      bool IsBaseInitializer = Record[Idx++];
+      if (IsBaseInitializer) {
+        BaseClassInfo = GetTypeSourceInfo(Cursor, Record, Idx);
+        IsBaseVirtual = Record[Idx++];
+      } else {
+        Member = cast<FieldDecl>(GetDecl(Record[Idx++]));
+      }
+      SourceLocation MemberLoc = ReadSourceLocation(Record, Idx);
+      Expr *Init = ReadExpr(Cursor);
+      FieldDecl *AnonUnionMember
+          = cast_or_null<FieldDecl>(GetDecl(Record[Idx++]));
+      SourceLocation LParenLoc = ReadSourceLocation(Record, Idx);
+      SourceLocation RParenLoc = ReadSourceLocation(Record, Idx);
+      bool IsWritten = Record[Idx++];
+      unsigned SourceOrderOrNumArrayIndices;
+      llvm::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(cast<VarDecl>(GetDecl(Record[Idx++])));
+      }
+      
+      CXXBaseOrMemberInitializer *BOMInit;
+      if (IsBaseInitializer) {
+        BOMInit = new (C) CXXBaseOrMemberInitializer(C, BaseClassInfo,
+                                                     IsBaseVirtual, LParenLoc,
+                                                     Init, RParenLoc);
+      } else if (IsWritten) {
+        BOMInit = new (C) CXXBaseOrMemberInitializer(C, Member, MemberLoc,
+                                                     LParenLoc, Init, RParenLoc);
+      } else {
+        BOMInit = CXXBaseOrMemberInitializer::Create(C, Member, MemberLoc,
+                                                     LParenLoc, Init, RParenLoc,
+                                                     Indices.data(),
+                                                     Indices.size());
+      }
+
+      BOMInit->setAnonUnionMember(AnonUnionMember);
+      BaseOrMemberInitializers[i] = BOMInit;
+    }
+  }
+
+  return std::make_pair(BaseOrMemberInitializers, NumInitializers);
+}
+
+NestedNameSpecifier *
+ASTReader::ReadNestedNameSpecifier(const RecordData &Record, unsigned &Idx) {
+  unsigned N = Record[Idx++];
+  NestedNameSpecifier *NNS = 0, *Prev = 0;
+  for (unsigned I = 0; I != N; ++I) {
+    NestedNameSpecifier::SpecifierKind Kind
+      = (NestedNameSpecifier::SpecifierKind)Record[Idx++];
+    switch (Kind) {
+    case NestedNameSpecifier::Identifier: {
+      IdentifierInfo *II = GetIdentifierInfo(Record, Idx);
+      NNS = NestedNameSpecifier::Create(*Context, Prev, II);
+      break;
+    }
+
+    case NestedNameSpecifier::Namespace: {
+      NamespaceDecl *NS = cast<NamespaceDecl>(GetDecl(Record[Idx++]));
+      NNS = NestedNameSpecifier::Create(*Context, Prev, NS);
+      break;
+    }
+
+    case NestedNameSpecifier::TypeSpec:
+    case NestedNameSpecifier::TypeSpecWithTemplate: {
+      Type *T = GetType(Record[Idx++]).getTypePtr();
+      bool Template = Record[Idx++];
+      NNS = NestedNameSpecifier::Create(*Context, Prev, Template, T);
+      break;
+    }
+
+    case NestedNameSpecifier::Global: {
+      NNS = NestedNameSpecifier::GlobalSpecifier(*Context);
+      // No associated value, and there can't be a prefix.
+      break;
+    }
+    }
+    Prev = NNS;
+  }
+  return NNS;
+}
+
+SourceRange
+ASTReader::ReadSourceRange(const RecordData &Record, unsigned &Idx) {
+  SourceLocation beg = SourceLocation::getFromRawEncoding(Record[Idx++]);
+  SourceLocation end = SourceLocation::getFromRawEncoding(Record[Idx++]);
+  return SourceRange(beg, end);
+}
+
+/// \brief Read an integral value
+llvm::APInt ASTReader::ReadAPInt(const RecordData &Record, unsigned &Idx) {
+  unsigned BitWidth = Record[Idx++];
+  unsigned NumWords = llvm::APInt::getNumWords(BitWidth);
+  llvm::APInt Result(BitWidth, NumWords, &Record[Idx]);
+  Idx += NumWords;
+  return Result;
+}
+
+/// \brief Read a signed integral value
+llvm::APSInt ASTReader::ReadAPSInt(const RecordData &Record, unsigned &Idx) {
+  bool isUnsigned = Record[Idx++];
+  return llvm::APSInt(ReadAPInt(Record, Idx), isUnsigned);
+}
+
+/// \brief Read a floating-point value
+llvm::APFloat ASTReader::ReadAPFloat(const RecordData &Record, unsigned &Idx) {
+  return llvm::APFloat(ReadAPInt(Record, Idx));
+}
+
+// \brief Read a string
+std::string ASTReader::ReadString(const RecordData &Record, unsigned &Idx) {
+  unsigned Len = Record[Idx++];
+  std::string Result(Record.data() + Idx, Record.data() + Idx + Len);
+  Idx += Len;
+  return Result;
+}
+
+CXXTemporary *ASTReader::ReadCXXTemporary(const RecordData &Record,
+                                          unsigned &Idx) {
+  CXXDestructorDecl *Decl = cast<CXXDestructorDecl>(GetDecl(Record[Idx++]));
+  return CXXTemporary::Create(*Context, Decl);
+}
+
+DiagnosticBuilder ASTReader::Diag(unsigned DiagID) {
+  return Diag(SourceLocation(), DiagID);
+}
+
+DiagnosticBuilder ASTReader::Diag(SourceLocation Loc, unsigned DiagID) {
+  return Diags.Report(FullSourceLoc(Loc, SourceMgr), DiagID);
+}
+
+/// \brief Retrieve the identifier table associated with the
+/// preprocessor.
+IdentifierTable &ASTReader::getIdentifierTable() {
+  assert(PP && "Forgot to set Preprocessor ?");
+  return PP->getIdentifierTable();
+}
+
+/// \brief Record that the given ID maps to the given switch-case
+/// statement.
+void ASTReader::RecordSwitchCaseID(SwitchCase *SC, unsigned ID) {
+  assert(SwitchCaseStmts[ID] == 0 && "Already have a SwitchCase with this ID");
+  SwitchCaseStmts[ID] = SC;
+}
+
+/// \brief Retrieve the switch-case statement with the given ID.
+SwitchCase *ASTReader::getSwitchCaseWithID(unsigned ID) {
+  assert(SwitchCaseStmts[ID] != 0 && "No SwitchCase with this ID");
+  return SwitchCaseStmts[ID];
+}
+
+/// \brief Record that the given label statement has been
+/// deserialized and has the given ID.
+void ASTReader::RecordLabelStmt(LabelStmt *S, unsigned ID) {
+  assert(LabelStmts.find(ID) == LabelStmts.end() &&
+         "Deserialized label twice");
+  LabelStmts[ID] = S;
+
+  // If we've already seen any goto statements that point to this
+  // label, resolve them now.
+  typedef std::multimap<unsigned, GotoStmt *>::iterator GotoIter;
+  std::pair<GotoIter, GotoIter> Gotos = UnresolvedGotoStmts.equal_range(ID);
+  for (GotoIter Goto = Gotos.first; Goto != Gotos.second; ++Goto)
+    Goto->second->setLabel(S);
+  UnresolvedGotoStmts.erase(Gotos.first, Gotos.second);
+
+  // If we've already seen any address-label statements that point to
+  // this label, resolve them now.
+  typedef std::multimap<unsigned, AddrLabelExpr *>::iterator AddrLabelIter;
+  std::pair<AddrLabelIter, AddrLabelIter> AddrLabels
+    = UnresolvedAddrLabelExprs.equal_range(ID);
+  for (AddrLabelIter AddrLabel = AddrLabels.first;
+       AddrLabel != AddrLabels.second; ++AddrLabel)
+    AddrLabel->second->setLabel(S);
+  UnresolvedAddrLabelExprs.erase(AddrLabels.first, AddrLabels.second);
+}
+
+/// \brief Set the label of the given statement to the label
+/// identified by ID.
+///
+/// Depending on the order in which the label and other statements
+/// referencing that label occur, this operation may complete
+/// immediately (updating the statement) or it may queue the
+/// statement to be back-patched later.
+void ASTReader::SetLabelOf(GotoStmt *S, unsigned ID) {
+  std::map<unsigned, LabelStmt *>::iterator Label = LabelStmts.find(ID);
+  if (Label != LabelStmts.end()) {
+    // We've already seen this label, so set the label of the goto and
+    // we're done.
+    S->setLabel(Label->second);
+  } else {
+    // We haven't seen this label yet, so add this goto to the set of
+    // unresolved goto statements.
+    UnresolvedGotoStmts.insert(std::make_pair(ID, S));
+  }
+}
+
+/// \brief Set the label of the given expression to the label
+/// identified by ID.
+///
+/// Depending on the order in which the label and other statements
+/// referencing that label occur, this operation may complete
+/// immediately (updating the statement) or it may queue the
+/// statement to be back-patched later.
+void ASTReader::SetLabelOf(AddrLabelExpr *S, unsigned ID) {
+  std::map<unsigned, LabelStmt *>::iterator Label = LabelStmts.find(ID);
+  if (Label != LabelStmts.end()) {
+    // We've already seen this label, so set the label of the
+    // label-address expression and we're done.
+    S->setLabel(Label->second);
+  } else {
+    // We haven't seen this label yet, so add this label-address
+    // expression to the set of unresolved label-address expressions.
+    UnresolvedAddrLabelExprs.insert(std::make_pair(ID, S));
+  }
+}
+
+void ASTReader::FinishedDeserializing() {
+  assert(NumCurrentElementsDeserializing &&
+         "FinishedDeserializing not paired with StartedDeserializing");
+  if (NumCurrentElementsDeserializing == 1) {
+    // If any identifiers with corresponding top-level declarations have
+    // been loaded, load those declarations now.
+    while (!PendingIdentifierInfos.empty()) {
+      SetGloballyVisibleDecls(PendingIdentifierInfos.front().II,
+                              PendingIdentifierInfos.front().DeclIDs, true);
+      PendingIdentifierInfos.pop_front();
+    }
+
+    // We are not in recursive loading, so it's safe to pass the "interesting"
+    // decls to the consumer.
+    if (Consumer)
+      PassInterestingDeclsToConsumer();
+  }
+  --NumCurrentElementsDeserializing;
+}
+
+ASTReader::ASTReader(Preprocessor &PP, ASTContext *Context,
+                     const char *isysroot, bool DisableValidation)
+  : Listener(new PCHValidator(PP, *this)), DeserializationListener(0),
+    SourceMgr(PP.getSourceManager()), FileMgr(PP.getFileManager()),
+    Diags(PP.getDiagnostics()), SemaObj(0), PP(&PP), Context(Context),
+    Consumer(0), isysroot(isysroot), DisableValidation(DisableValidation),
+    NumStatHits(0), NumStatMisses(0), NumSLocEntriesRead(0),
+    TotalNumSLocEntries(0), NumStatementsRead(0), TotalNumStatements(0),
+    NumMacrosRead(0), TotalNumMacros(0), NumSelectorsRead(0),
+    NumMethodPoolEntriesRead(0), NumMethodPoolMisses(0),
+    TotalNumMethodPoolEntries(0), NumLexicalDeclContextsRead(0),
+    TotalLexicalDeclContexts(0), NumVisibleDeclContextsRead(0),
+    TotalVisibleDeclContexts(0), NumCurrentElementsDeserializing(0) {
+  RelocatablePCH = false;
+}
+
+ASTReader::ASTReader(SourceManager &SourceMgr, FileManager &FileMgr,
+                     Diagnostic &Diags, const char *isysroot,
+                     bool DisableValidation)
+  : DeserializationListener(0), SourceMgr(SourceMgr), FileMgr(FileMgr),
+    Diags(Diags), SemaObj(0), PP(0), Context(0), Consumer(0),
+    isysroot(isysroot), DisableValidation(DisableValidation), NumStatHits(0),
+    NumStatMisses(0), NumSLocEntriesRead(0), TotalNumSLocEntries(0),
+    NumStatementsRead(0), TotalNumStatements(0), NumMacrosRead(0),
+    TotalNumMacros(0), NumSelectorsRead(0), NumMethodPoolEntriesRead(0),
+    NumMethodPoolMisses(0), TotalNumMethodPoolEntries(0),
+    NumLexicalDeclContextsRead(0), TotalLexicalDeclContexts(0),
+    NumVisibleDeclContextsRead(0), TotalVisibleDeclContexts(0),
+    NumCurrentElementsDeserializing(0) {
+  RelocatablePCH = false;
+}
+
+ASTReader::~ASTReader() {
+  for (unsigned i = 0, e = Chain.size(); i != e; ++i)
+    delete Chain[e - i - 1];
+  // Delete all visible decl lookup tables
+  for (DeclContextOffsetsMap::iterator I = DeclContextOffsets.begin(),
+                                       E = DeclContextOffsets.end();
+       I != E; ++I) {
+    for (DeclContextInfos::iterator J = I->second.begin(), F = I->second.end();
+         J != F; ++J) {
+      if (J->NameLookupTableData)
+        delete static_cast<ASTDeclContextNameLookupTable*>(
+            J->NameLookupTableData);
+    }
+  }
+  for (DeclContextVisibleUpdatesPending::iterator
+           I = PendingVisibleUpdates.begin(),
+           E = PendingVisibleUpdates.end();
+       I != E; ++I) {
+    for (DeclContextVisibleUpdates::iterator J = I->second.begin(),
+                                             F = I->second.end();
+         J != F; ++J)
+      delete static_cast<ASTDeclContextNameLookupTable*>(*J);
+  }
+}
+
+ASTReader::PerFileData::PerFileData()
+  : StatCache(0), LocalNumSLocEntries(0), LocalNumTypes(0), TypeOffsets(0),
+    LocalNumDecls(0), DeclOffsets(0), LocalNumIdentifiers(0),
+    IdentifierOffsets(0), IdentifierTableData(0), IdentifierLookupTable(0),
+    LocalNumMacroDefinitions(0), MacroDefinitionOffsets(0),
+    NumPreallocatedPreprocessingEntities(0), SelectorLookupTable(0),
+    SelectorLookupTableData(0), SelectorOffsets(0), LocalNumSelectors(0)
+{}
+
+ASTReader::PerFileData::~PerFileData() {
+  delete static_cast<ASTIdentifierLookupTable *>(IdentifierLookupTable);
+  delete static_cast<ASTSelectorLookupTable *>(SelectorLookupTable);
+}
+