[cfe-commits] r107087 - in /cfe/trunk: include/clang/Frontend/PCHReader.h include/clang/Frontend/PCHWriter.h lib/Frontend/PCHReader.cpp lib/Frontend/PCHReaderDecl.cpp lib/Frontend/PCHReaderStmt.cpp lib/Frontend/PCHWriter.cpp lib/Frontend/PCHWriterStmt.cpp test/PCH/exprs.c test/PCH/exprs.h

Argyrios Kyrtzidis akyrtzi at gmail.com
Mon Jun 28 15:28:35 PDT 2010


Author: akirtzidis
Date: Mon Jun 28 17:28:35 2010
New Revision: 107087

URL: http://llvm.org/viewvc/llvm-project?rev=107087&view=rev
Log:
Modify the way sub-statements are stored and retrieved from PCH.

Before this commit, sub-stmts were stored as encountered and when they were placed in the Stmts stack we had to know what index
each stmt operand has. This complicated supporting variable sub-stmts and sub-stmts that were contained in TypeSourceInfos, e.g.

x = sizeof(int[1]);

would crash PCH.

Now, sub-stmts are stored in reverse order, from last to first, so that when reading them, in order to get the next sub-stmt we just
need to pop the last stmt from the stack. This greatly simplified the way stmts are written and read (just use PCHWriter::AddStmt and
 PCHReader::ReadStmt accordingly) and allowed variable stmt operands and TypeSourceInfo exprs.

Modified:
    cfe/trunk/include/clang/Frontend/PCHReader.h
    cfe/trunk/include/clang/Frontend/PCHWriter.h
    cfe/trunk/lib/Frontend/PCHReader.cpp
    cfe/trunk/lib/Frontend/PCHReaderDecl.cpp
    cfe/trunk/lib/Frontend/PCHReaderStmt.cpp
    cfe/trunk/lib/Frontend/PCHWriter.cpp
    cfe/trunk/lib/Frontend/PCHWriterStmt.cpp
    cfe/trunk/test/PCH/exprs.c
    cfe/trunk/test/PCH/exprs.h

Modified: cfe/trunk/include/clang/Frontend/PCHReader.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Frontend/PCHReader.h?rev=107087&r1=107086&r2=107087&view=diff
==============================================================================
--- cfe/trunk/include/clang/Frontend/PCHReader.h (original)
+++ cfe/trunk/include/clang/Frontend/PCHReader.h Mon Jun 28 17:28:35 2010
@@ -449,6 +449,34 @@
   /// Objective-C protocols.
   llvm::SmallVector<Decl *, 16> InterestingDecls;
 
+  /// \brief When reading a Stmt tree, Stmt operands are placed in this stack.
+  llvm::SmallVector<Stmt *, 16> StmtStack;
+
+  /// \brief What kind of records we are reading.
+  enum ReadingKind {
+    Read_Decl, Read_Type, Read_Stmt
+  };
+
+  /// \brief What kind of records we are reading. 
+  ReadingKind ReadingKind;
+
+  /// \brief RAII object to change the reading kind.
+  class ReadingKindTracker {
+    PCHReader &Reader;
+    enum ReadingKind PrevKind;
+
+    ReadingKindTracker(const ReadingKindTracker&); // do not implement
+    ReadingKindTracker &operator=(const ReadingKindTracker&);// do not implement
+
+  public:
+    ReadingKindTracker(enum ReadingKind newKind, PCHReader &reader)
+      : Reader(reader), PrevKind(Reader.ReadingKind) {
+      Reader.ReadingKind = newKind;
+    }
+
+    ~ReadingKindTracker() { Reader.ReadingKind = PrevKind; }
+  };
+
   /// \brief The file ID for the predefines buffer in the PCH file.
   FileID PCHPredefinesBufferID;
 
@@ -469,6 +497,9 @@
   /// predefines buffer may contain additional definitions.
   std::string SuggestedPredefines;
 
+  /// \brief Reads a statement from the specified cursor.
+  Stmt *ReadStmtFromStream(llvm::BitstreamCursor &Cursor);
+
   void MaybeAddSystemRootToFilename(std::string &Filename);
 
   PCHReadResult ReadPCHBlock();
@@ -563,19 +594,6 @@
   /// \brief Read preprocessed entities into the 
   virtual void ReadPreprocessedEntities();
 
-  /// \brief Abstract interface for reading expressions.
-  class ExprReader {
-  public:
-    virtual Expr *Read();
-  };
-
-  /// \brief Reads a TemplateArgumentLocInfo appropriate for the
-  /// given TemplateArgument kind.
-  TemplateArgumentLocInfo
-  GetTemplateArgumentLocInfo(TemplateArgument::ArgKind Kind,
-                             const RecordData &Record, unsigned &Idx,
-                             ExprReader &ExprRdr);
-
   /// \brief Reads a TemplateArgumentLocInfo appropriate for the
   /// given TemplateArgument kind.
   TemplateArgumentLocInfo
@@ -584,11 +602,6 @@
 
   /// \brief Reads a TemplateArgumentLoc.
   TemplateArgumentLoc ReadTemplateArgumentLoc(const RecordData &Record,
-                                              unsigned &Idx,
-                                              ExprReader &ExprRdr);
-
-  /// \brief Reads a TemplateArgumentLoc.
-  TemplateArgumentLoc ReadTemplateArgumentLoc(const RecordData &Record,
                                               unsigned &Idx);
 
   /// \brief Reads a declarator info from the given record.
@@ -719,10 +732,6 @@
   TemplateName ReadTemplateName(const RecordData &Record, unsigned &Idx);
 
   /// \brief Read a template argument.
-  TemplateArgument ReadTemplateArgument(const RecordData &Record,unsigned &Idx,
-                                        ExprReader &ExprRdr);
-
-  /// \brief Read a template argument.
   TemplateArgument ReadTemplateArgument(const RecordData &Record,unsigned &Idx);
   
   /// \brief Read a template parameter list.
@@ -759,19 +768,11 @@
   /// \brief Reads attributes from the current stream position.
   Attr *ReadAttributes();
 
-  /// \brief ReadDeclExpr - Reads an expression from the current decl cursor.
-  Expr *ReadDeclExpr();
-
-  /// \brief ReadTypeExpr - Reads an expression from the current type cursor.
-  Expr *ReadTypeExpr();
+  /// \brief Reads a statement.
+  Stmt *ReadStmt();
 
-  /// \brief Reads a statement from the specified cursor.
-  Stmt *ReadStmt(llvm::BitstreamCursor &Cursor);
-
-  /// \brief Read a statement from the current DeclCursor.
-  Stmt *ReadDeclStmt() {
-    return ReadStmt(DeclsCursor);
-  }
+  /// \brief Reads an expression.
+  Expr *ReadExpr();
 
   /// \brief Reads the macro record located at the given offset.
   void ReadMacroRecord(uint64_t Offset);

Modified: cfe/trunk/include/clang/Frontend/PCHWriter.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Frontend/PCHWriter.h?rev=107087&r1=107086&r2=107087&view=diff
==============================================================================
--- cfe/trunk/include/clang/Frontend/PCHWriter.h (original)
+++ cfe/trunk/include/clang/Frontend/PCHWriter.h Mon Jun 28 17:28:35 2010
@@ -189,7 +189,11 @@
 
   /// \brief Statements that we've encountered while serializing a
   /// declaration or type.
-  llvm::SmallVector<Stmt *, 8> StmtsToEmit;
+  llvm::SmallVector<Stmt *, 16> StmtsToEmit;
+  
+  /// \brief Statements collection to use for PCHWriter::AddStmt().
+  /// It will point to StmtsToEmit unless it is overriden. 
+  llvm::SmallVector<Stmt *, 16> *CollectedStmts;
 
   /// \brief Mapping from SwitchCase statements to IDs.
   std::map<SwitchCase *, unsigned> SwitchCaseIDs;
@@ -211,8 +215,8 @@
   /// file.
   unsigned NumVisibleDeclContexts;
 
-  /// \brief True when we are in Stmts emitting mode.
-  bool EmittingStmts;
+  /// \brief Write the given subexpression to the bitstream.
+  void WriteSubStmt(Stmt *S);
 
   void WriteBlockInfoBlock();
   void WriteMetadata(ASTContext &Context, const char *isysroot);
@@ -359,15 +363,9 @@
   /// the corresponding statements just after the type or
   /// declaration.
   void AddStmt(Stmt *S) {
-    if (EmittingStmts)
-      WriteSubStmt(S);
-    else
-      StmtsToEmit.push_back(S);
+      CollectedStmts->push_back(S);
   }
 
-  /// \brief Write the given subexpression to the bitstream.
-  void WriteSubStmt(Stmt *S);
-
   /// \brief Flush all of the statements and expressions that have
   /// been added to the queue via AddStmt().
   void FlushStmts();

Modified: cfe/trunk/lib/Frontend/PCHReader.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/PCHReader.cpp?rev=107087&r1=107086&r2=107087&view=diff
==============================================================================
--- cfe/trunk/lib/Frontend/PCHReader.cpp (original)
+++ cfe/trunk/lib/Frontend/PCHReader.cpp Mon Jun 28 17:28:35 2010
@@ -321,18 +321,6 @@
 // PCH reader implementation
 //===----------------------------------------------------------------------===//
 
-// Give ExprReader's VTable a home.
-Expr *PCHReader::ExprReader::Read() { return 0; }
-
-namespace {
-  class DeclExprReader : public PCHReader::ExprReader {
-    PCHReader &Reader;
-  public:
-    DeclExprReader(PCHReader &reader) : Reader(reader) { }
-    virtual Expr *Read() { return Reader.ReadDeclExpr(); }
-  };
-} // anonymous namespace
-
 PCHReader::PCHReader(Preprocessor &PP, ASTContext *Context,
                      const char *isysroot)
   : Listener(new PCHValidator(PP, *this)), SourceMgr(PP.getSourceManager()),
@@ -372,14 +360,6 @@
 
 PCHReader::~PCHReader() {}
 
-Expr *PCHReader::ReadDeclExpr() {
-  return dyn_cast_or_null<Expr>(ReadStmt(DeclsCursor));
-}
-
-Expr *PCHReader::ReadTypeExpr() {
-  return dyn_cast_or_null<Expr>(ReadStmt(DeclsCursor));
-}
-
 
 namespace {
 class PCHMethodPoolLookupTrait {
@@ -1969,6 +1949,8 @@
   // after reading this type.
   SavedStreamPosition SavedPosition(DeclsCursor);
 
+  ReadingKindTracker ReadingKind(Read_Type, *this);
+  
   // Note that we are loading a type record.
   LoadingTypeOrDecl Loading(*this);
 
@@ -2064,7 +2046,7 @@
     unsigned IndexTypeQuals = Record[2];
     SourceLocation LBLoc = SourceLocation::getFromRawEncoding(Record[3]);
     SourceLocation RBLoc = SourceLocation::getFromRawEncoding(Record[4]);
-    return Context->getVariableArrayType(ElementType, ReadTypeExpr(),
+    return Context->getVariableArrayType(ElementType, ReadExpr(),
                                          ASM, IndexTypeQuals,
                                          SourceRange(LBLoc, RBLoc));
   }
@@ -2141,7 +2123,7 @@
     return Context->getTypeDeclType(cast<TypedefDecl>(GetDecl(Record[0])));
 
   case pch::TYPE_TYPEOF_EXPR:
-    return Context->getTypeOfExprType(ReadTypeExpr());
+    return Context->getTypeOfExprType(ReadExpr());
 
   case pch::TYPE_TYPEOF: {
     if (Record.size() != 1) {
@@ -2153,7 +2135,7 @@
   }
 
   case pch::TYPE_DECLTYPE:
-    return Context->getDecltypeType(ReadTypeExpr());
+    return Context->getDecltypeType(ReadExpr());
 
   case pch::TYPE_RECORD:
     if (Record.size() != 1) {
@@ -2319,7 +2301,7 @@
   TL.setLBracketLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   TL.setRBracketLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   if (Record[Idx++])
-    TL.setSizeExpr(Reader.ReadDeclExpr());
+    TL.setSizeExpr(Reader.ReadExpr());
   else
     TL.setSizeExpr(0);
 }
@@ -2511,10 +2493,10 @@
 TemplateArgumentLocInfo
 PCHReader::GetTemplateArgumentLocInfo(TemplateArgument::ArgKind Kind,
                                       const RecordData &Record,
-                                      unsigned &Index, ExprReader &ExprRdr) {
+                                      unsigned &Index) {
   switch (Kind) {
   case TemplateArgument::Expression:
-    return ExprRdr.Read();
+    return ReadExpr();
   case TemplateArgument::Type:
     return GetTypeSourceInfo(Record, Index);
   case TemplateArgument::Template: {
@@ -2532,32 +2514,16 @@
   return TemplateArgumentLocInfo();
 }
 
-TemplateArgumentLocInfo
-PCHReader::GetTemplateArgumentLocInfo(TemplateArgument::ArgKind Kind,
-                                      const RecordData &Record,
-                                      unsigned &Index) {
-  DeclExprReader DeclExprReader(*this);
-  return GetTemplateArgumentLocInfo(Kind, Record, Index, DeclExprReader);
-}
-
 TemplateArgumentLoc
-PCHReader::ReadTemplateArgumentLoc(const RecordData &Record, unsigned &Index,
-                                   ExprReader &ExprRdr) {
-  TemplateArgument Arg = ReadTemplateArgument(Record, Index, ExprRdr);
+PCHReader::ReadTemplateArgumentLoc(const RecordData &Record, unsigned &Index) {
+  TemplateArgument Arg = ReadTemplateArgument(Record, Index);
 
   if (Arg.getKind() == TemplateArgument::Expression) {
     if (Record[Index++]) // bool InfoHasSameExpr.
       return TemplateArgumentLoc(Arg, TemplateArgumentLocInfo(Arg.getAsExpr()));
   }
   return TemplateArgumentLoc(Arg, GetTemplateArgumentLocInfo(Arg.getKind(),
-                                                             Record, Index,
-                                                             ExprRdr));
-}
-
-TemplateArgumentLoc
-PCHReader::ReadTemplateArgumentLoc(const RecordData &Record, unsigned &Index) {
-  DeclExprReader DeclExprReader(*this);
-  return ReadTemplateArgumentLoc(Record, Index, DeclExprReader);
+                                                             Record, Index));
 }
 
 Decl *PCHReader::GetExternalDecl(uint32_t ID) {
@@ -2589,7 +2555,7 @@
   // Since we know tha this statement is part of a decl, make sure to use the
   // decl cursor to read it.
   DeclsCursor.JumpToBit(Offset);
-  return ReadStmt(DeclsCursor);
+  return ReadStmtFromStream(DeclsCursor);
 }
 
 bool PCHReader::FindExternalLexicalDecls(const DeclContext *DC,
@@ -3034,8 +3000,7 @@
 }
 
 TemplateArgument
-PCHReader::ReadTemplateArgument(const RecordData &Record, unsigned &Idx,
-                                ExprReader &ExprRdr) {
+PCHReader::ReadTemplateArgument(const RecordData &Record, unsigned &Idx) {
   switch ((TemplateArgument::ArgKind)Record[Idx++]) {
   case TemplateArgument::Null:
     return TemplateArgument();
@@ -3051,13 +3016,13 @@
   case TemplateArgument::Template:
     return TemplateArgument(ReadTemplateName(Record, Idx));
   case TemplateArgument::Expression:
-    return TemplateArgument(ExprRdr.Read());
+    return TemplateArgument(ReadExpr());
   case TemplateArgument::Pack: {
     unsigned NumArgs = Record[Idx++];
     llvm::SmallVector<TemplateArgument, 8> Args;
     Args.reserve(NumArgs);
     while (NumArgs--)
-      Args.push_back(ReadTemplateArgument(Record, Idx, ExprRdr));
+      Args.push_back(ReadTemplateArgument(Record, Idx));
     TemplateArgument TemplArg;
     TemplArg.setArgumentPack(Args.data(), Args.size(), /*CopyArgs=*/true);
     return TemplArg;
@@ -3068,12 +3033,6 @@
   return TemplateArgument();
 }
 
-TemplateArgument
-PCHReader::ReadTemplateArgument(const RecordData &Record, unsigned &Idx) {
-  DeclExprReader DeclExprReader(*this);
-  return ReadTemplateArgument(Record, Idx, DeclExprReader);
-}
-
 TemplateParameterList *
 PCHReader::ReadTemplateParameterList(const RecordData &Record, unsigned &Idx) {
   SourceLocation TemplateLoc = ReadSourceLocation(Record, Idx);

Modified: cfe/trunk/lib/Frontend/PCHReaderDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/PCHReaderDecl.cpp?rev=107087&r1=107086&r2=107087&view=diff
==============================================================================
--- cfe/trunk/lib/Frontend/PCHReaderDecl.cpp (original)
+++ cfe/trunk/lib/Frontend/PCHReaderDecl.cpp Mon Jun 28 17:28:35 2010
@@ -184,7 +184,7 @@
 void PCHDeclReader::VisitEnumConstantDecl(EnumConstantDecl *ECD) {
   VisitValueDecl(ECD);
   if (Record[Idx++])
-    ECD->setInitExpr(Reader.ReadDeclExpr());
+    ECD->setInitExpr(Reader.ReadExpr());
   ECD->setInitVal(Reader.ReadAPSInt(Record, Idx));
 }
 
@@ -299,7 +299,7 @@
   if (Record[Idx++]) {
     // In practice, this won't be executed (since method definitions
     // don't occur in header files).
-    MD->setBody(Reader.ReadDeclStmt());
+    MD->setBody(Reader.ReadStmt());
     MD->setSelfDecl(cast<ImplicitParamDecl>(Reader.GetDecl(Record[Idx++])));
     MD->setCmdDecl(cast<ImplicitParamDecl>(Reader.GetDecl(Record[Idx++])));
   }
@@ -493,7 +493,7 @@
   VisitDeclaratorDecl(FD);
   FD->setMutable(Record[Idx++]);
   if (Record[Idx++])
-    FD->setBitWidth(Reader.ReadDeclExpr());
+    FD->setBitWidth(Reader.ReadExpr());
 }
 
 void PCHDeclReader::VisitVarDecl(VarDecl *VD) {
@@ -508,7 +508,7 @@
   VD->setPreviousDeclaration(
                          cast_or_null<VarDecl>(Reader.GetDecl(Record[Idx++])));
   if (Record[Idx++])
-    VD->setInit(Reader.ReadDeclExpr());
+    VD->setInit(Reader.ReadExpr());
 }
 
 void PCHDeclReader::VisitImplicitParamDecl(ImplicitParamDecl *PD) {
@@ -523,12 +523,12 @@
 
 void PCHDeclReader::VisitFileScopeAsmDecl(FileScopeAsmDecl *AD) {
   VisitDecl(AD);
-  AD->setAsmString(cast<StringLiteral>(Reader.ReadDeclExpr()));
+  AD->setAsmString(cast<StringLiteral>(Reader.ReadExpr()));
 }
 
 void PCHDeclReader::VisitBlockDecl(BlockDecl *BD) {
   VisitDecl(BD);
-  BD->setBody(cast_or_null<CompoundStmt>(Reader.ReadDeclStmt()));
+  BD->setBody(cast_or_null<CompoundStmt>(Reader.ReadStmt()));
   BD->setSignatureAsWritten(Reader.GetTypeSourceInfo(Record, Idx));
   unsigned NumParams = Record[Idx++];
   llvm::SmallVector<ParmVarDecl *, 16> Params;
@@ -861,7 +861,7 @@
   D->setPosition(Record[Idx++]);
   // Rest of NonTypeTemplateParmDecl.
   if (Record[Idx++]) {
-    Expr *DefArg = Reader.ReadDeclExpr();
+    Expr *DefArg = Reader.ReadExpr();
     bool Inherited = Record[Idx++];
     D->setDefaultArgument(DefArg, Inherited);
  }
@@ -1106,6 +1106,8 @@
   // after reading this declaration.
   SavedStreamPosition SavedPosition(DeclsCursor);
 
+  ReadingKindTracker ReadingKind(Read_Decl, *this);
+
   // Note that we are loading a declaration record.
   LoadingTypeOrDecl Loading(*this);
 

Modified: cfe/trunk/lib/Frontend/PCHReaderStmt.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/PCHReaderStmt.cpp?rev=107087&r1=107086&r2=107087&view=diff
==============================================================================
--- cfe/trunk/lib/Frontend/PCHReaderStmt.cpp (original)
+++ cfe/trunk/lib/Frontend/PCHReaderStmt.cpp Mon Jun 28 17:28:35 2010
@@ -19,16 +19,15 @@
 
 namespace {
 
-  class PCHStmtReader : public StmtVisitor<PCHStmtReader, unsigned> {
+  class PCHStmtReader : public StmtVisitor<PCHStmtReader> {
     PCHReader &Reader;
     const PCHReader::RecordData &Record;
     unsigned &Idx;
-    llvm::SmallVectorImpl<Stmt *> &StmtStack;
 
   public:
     PCHStmtReader(PCHReader &Reader, const PCHReader::RecordData &Record,
-                  unsigned &Idx, llvm::SmallVectorImpl<Stmt *> &StmtStack)
-      : Reader(Reader), Record(Record), Idx(Idx), StmtStack(StmtStack) { }
+                  unsigned &Idx)
+      : Reader(Reader), Record(Record), Idx(Idx) { }
 
     /// \brief The number of record fields required for the Stmt class
     /// itself.
@@ -39,225 +38,194 @@
     static const unsigned NumExprFields = NumStmtFields + 3;
     
     /// \brief Read and initialize a ExplicitTemplateArgumentList structure.
-    /// \return the number of Exprs that were read.
-    unsigned
-    ReadExplicitTemplateArgumentList(ExplicitTemplateArgumentList &ArgList,
-                                     unsigned NumTemplateArgs,
-                            llvm::SmallVectorImpl<Stmt *>::iterator EndOfExprs);
-
-    // Each of the Visit* functions reads in part of the expression
-    // from the given record and the current expression stack, then
-    // return the total number of operands that it read from the
-    // expression stack.
-
-    unsigned VisitStmt(Stmt *S);
-    unsigned VisitNullStmt(NullStmt *S);
-    unsigned VisitCompoundStmt(CompoundStmt *S);
-    unsigned VisitSwitchCase(SwitchCase *S);
-    unsigned VisitCaseStmt(CaseStmt *S);
-    unsigned VisitDefaultStmt(DefaultStmt *S);
-    unsigned VisitLabelStmt(LabelStmt *S);
-    unsigned VisitIfStmt(IfStmt *S);
-    unsigned VisitSwitchStmt(SwitchStmt *S);
-    unsigned VisitWhileStmt(WhileStmt *S);
-    unsigned VisitDoStmt(DoStmt *S);
-    unsigned VisitForStmt(ForStmt *S);
-    unsigned VisitGotoStmt(GotoStmt *S);
-    unsigned VisitIndirectGotoStmt(IndirectGotoStmt *S);
-    unsigned VisitContinueStmt(ContinueStmt *S);
-    unsigned VisitBreakStmt(BreakStmt *S);
-    unsigned VisitReturnStmt(ReturnStmt *S);
-    unsigned VisitDeclStmt(DeclStmt *S);
-    unsigned VisitAsmStmt(AsmStmt *S);
-    unsigned VisitExpr(Expr *E);
-    unsigned VisitPredefinedExpr(PredefinedExpr *E);
-    unsigned VisitDeclRefExpr(DeclRefExpr *E);
-    unsigned VisitIntegerLiteral(IntegerLiteral *E);
-    unsigned VisitFloatingLiteral(FloatingLiteral *E);
-    unsigned VisitImaginaryLiteral(ImaginaryLiteral *E);
-    unsigned VisitStringLiteral(StringLiteral *E);
-    unsigned VisitCharacterLiteral(CharacterLiteral *E);
-    unsigned VisitParenExpr(ParenExpr *E);
-    unsigned VisitUnaryOperator(UnaryOperator *E);
-    unsigned VisitOffsetOfExpr(OffsetOfExpr *E);
-    unsigned VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E);
-    unsigned VisitArraySubscriptExpr(ArraySubscriptExpr *E);
-    unsigned VisitCallExpr(CallExpr *E);
-    unsigned VisitMemberExpr(MemberExpr *E);
-    unsigned VisitCastExpr(CastExpr *E);
-    unsigned VisitBinaryOperator(BinaryOperator *E);
-    unsigned VisitCompoundAssignOperator(CompoundAssignOperator *E);
-    unsigned VisitConditionalOperator(ConditionalOperator *E);
-    unsigned VisitImplicitCastExpr(ImplicitCastExpr *E);
-    unsigned VisitExplicitCastExpr(ExplicitCastExpr *E);
-    unsigned VisitCStyleCastExpr(CStyleCastExpr *E);
-    unsigned VisitCompoundLiteralExpr(CompoundLiteralExpr *E);
-    unsigned VisitExtVectorElementExpr(ExtVectorElementExpr *E);
-    unsigned VisitInitListExpr(InitListExpr *E);
-    unsigned VisitDesignatedInitExpr(DesignatedInitExpr *E);
-    unsigned VisitImplicitValueInitExpr(ImplicitValueInitExpr *E);
-    unsigned VisitVAArgExpr(VAArgExpr *E);
-    unsigned VisitAddrLabelExpr(AddrLabelExpr *E);
-    unsigned VisitStmtExpr(StmtExpr *E);
-    unsigned VisitTypesCompatibleExpr(TypesCompatibleExpr *E);
-    unsigned VisitChooseExpr(ChooseExpr *E);
-    unsigned VisitGNUNullExpr(GNUNullExpr *E);
-    unsigned VisitShuffleVectorExpr(ShuffleVectorExpr *E);
-    unsigned VisitBlockExpr(BlockExpr *E);
-    unsigned VisitBlockDeclRefExpr(BlockDeclRefExpr *E);
-    unsigned VisitObjCStringLiteral(ObjCStringLiteral *E);
-    unsigned VisitObjCEncodeExpr(ObjCEncodeExpr *E);
-    unsigned VisitObjCSelectorExpr(ObjCSelectorExpr *E);
-    unsigned VisitObjCProtocolExpr(ObjCProtocolExpr *E);
-    unsigned VisitObjCIvarRefExpr(ObjCIvarRefExpr *E);
-    unsigned VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E);
-    unsigned VisitObjCImplicitSetterGetterRefExpr(
+    void ReadExplicitTemplateArgumentList(ExplicitTemplateArgumentList &ArgList,
+                                          unsigned NumTemplateArgs);
+
+    void VisitStmt(Stmt *S);
+    void VisitNullStmt(NullStmt *S);
+    void VisitCompoundStmt(CompoundStmt *S);
+    void VisitSwitchCase(SwitchCase *S);
+    void VisitCaseStmt(CaseStmt *S);
+    void VisitDefaultStmt(DefaultStmt *S);
+    void VisitLabelStmt(LabelStmt *S);
+    void VisitIfStmt(IfStmt *S);
+    void VisitSwitchStmt(SwitchStmt *S);
+    void VisitWhileStmt(WhileStmt *S);
+    void VisitDoStmt(DoStmt *S);
+    void VisitForStmt(ForStmt *S);
+    void VisitGotoStmt(GotoStmt *S);
+    void VisitIndirectGotoStmt(IndirectGotoStmt *S);
+    void VisitContinueStmt(ContinueStmt *S);
+    void VisitBreakStmt(BreakStmt *S);
+    void VisitReturnStmt(ReturnStmt *S);
+    void VisitDeclStmt(DeclStmt *S);
+    void VisitAsmStmt(AsmStmt *S);
+    void VisitExpr(Expr *E);
+    void VisitPredefinedExpr(PredefinedExpr *E);
+    void VisitDeclRefExpr(DeclRefExpr *E);
+    void VisitIntegerLiteral(IntegerLiteral *E);
+    void VisitFloatingLiteral(FloatingLiteral *E);
+    void VisitImaginaryLiteral(ImaginaryLiteral *E);
+    void VisitStringLiteral(StringLiteral *E);
+    void VisitCharacterLiteral(CharacterLiteral *E);
+    void VisitParenExpr(ParenExpr *E);
+    void VisitUnaryOperator(UnaryOperator *E);
+    void VisitOffsetOfExpr(OffsetOfExpr *E);
+    void VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E);
+    void VisitArraySubscriptExpr(ArraySubscriptExpr *E);
+    void VisitCallExpr(CallExpr *E);
+    void VisitMemberExpr(MemberExpr *E);
+    void VisitCastExpr(CastExpr *E);
+    void VisitBinaryOperator(BinaryOperator *E);
+    void VisitCompoundAssignOperator(CompoundAssignOperator *E);
+    void VisitConditionalOperator(ConditionalOperator *E);
+    void VisitImplicitCastExpr(ImplicitCastExpr *E);
+    void VisitExplicitCastExpr(ExplicitCastExpr *E);
+    void VisitCStyleCastExpr(CStyleCastExpr *E);
+    void VisitCompoundLiteralExpr(CompoundLiteralExpr *E);
+    void VisitExtVectorElementExpr(ExtVectorElementExpr *E);
+    void VisitInitListExpr(InitListExpr *E);
+    void VisitDesignatedInitExpr(DesignatedInitExpr *E);
+    void VisitImplicitValueInitExpr(ImplicitValueInitExpr *E);
+    void VisitVAArgExpr(VAArgExpr *E);
+    void VisitAddrLabelExpr(AddrLabelExpr *E);
+    void VisitStmtExpr(StmtExpr *E);
+    void VisitTypesCompatibleExpr(TypesCompatibleExpr *E);
+    void VisitChooseExpr(ChooseExpr *E);
+    void VisitGNUNullExpr(GNUNullExpr *E);
+    void VisitShuffleVectorExpr(ShuffleVectorExpr *E);
+    void VisitBlockExpr(BlockExpr *E);
+    void VisitBlockDeclRefExpr(BlockDeclRefExpr *E);
+    void VisitObjCStringLiteral(ObjCStringLiteral *E);
+    void VisitObjCEncodeExpr(ObjCEncodeExpr *E);
+    void VisitObjCSelectorExpr(ObjCSelectorExpr *E);
+    void VisitObjCProtocolExpr(ObjCProtocolExpr *E);
+    void VisitObjCIvarRefExpr(ObjCIvarRefExpr *E);
+    void VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E);
+    void VisitObjCImplicitSetterGetterRefExpr(
                             ObjCImplicitSetterGetterRefExpr *E);
-    unsigned VisitObjCMessageExpr(ObjCMessageExpr *E);
-    unsigned VisitObjCSuperExpr(ObjCSuperExpr *E);
-    unsigned VisitObjCIsaExpr(ObjCIsaExpr *E);
-
-    unsigned VisitObjCForCollectionStmt(ObjCForCollectionStmt *);
-    unsigned VisitObjCAtCatchStmt(ObjCAtCatchStmt *);
-    unsigned VisitObjCAtFinallyStmt(ObjCAtFinallyStmt *);
-    unsigned VisitObjCAtTryStmt(ObjCAtTryStmt *);
-    unsigned VisitObjCAtSynchronizedStmt(ObjCAtSynchronizedStmt *);
-    unsigned VisitObjCAtThrowStmt(ObjCAtThrowStmt *);
-
-    unsigned VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E);
-    unsigned VisitCXXConstructExpr(CXXConstructExpr *E);
-    unsigned VisitCXXNamedCastExpr(CXXNamedCastExpr *E);
-    unsigned VisitCXXStaticCastExpr(CXXStaticCastExpr *E);
-    unsigned VisitCXXDynamicCastExpr(CXXDynamicCastExpr *E);
-    unsigned VisitCXXReinterpretCastExpr(CXXReinterpretCastExpr *E);
-    unsigned VisitCXXConstCastExpr(CXXConstCastExpr *E);
-    unsigned VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr *E);
-    unsigned VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr *E);
-    unsigned VisitCXXNullPtrLiteralExpr(CXXNullPtrLiteralExpr *E);
-    unsigned VisitCXXTypeidExpr(CXXTypeidExpr *E);
-    unsigned VisitCXXThisExpr(CXXThisExpr *E);
-    unsigned VisitCXXThrowExpr(CXXThrowExpr *E);
-    unsigned VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E);
-    unsigned VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E);
+    void VisitObjCMessageExpr(ObjCMessageExpr *E);
+    void VisitObjCSuperExpr(ObjCSuperExpr *E);
+    void VisitObjCIsaExpr(ObjCIsaExpr *E);
+
+    void VisitObjCForCollectionStmt(ObjCForCollectionStmt *);
+    void VisitObjCAtCatchStmt(ObjCAtCatchStmt *);
+    void VisitObjCAtFinallyStmt(ObjCAtFinallyStmt *);
+    void VisitObjCAtTryStmt(ObjCAtTryStmt *);
+    void VisitObjCAtSynchronizedStmt(ObjCAtSynchronizedStmt *);
+    void VisitObjCAtThrowStmt(ObjCAtThrowStmt *);
+
+    void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E);
+    void VisitCXXConstructExpr(CXXConstructExpr *E);
+    void VisitCXXNamedCastExpr(CXXNamedCastExpr *E);
+    void VisitCXXStaticCastExpr(CXXStaticCastExpr *E);
+    void VisitCXXDynamicCastExpr(CXXDynamicCastExpr *E);
+    void VisitCXXReinterpretCastExpr(CXXReinterpretCastExpr *E);
+    void VisitCXXConstCastExpr(CXXConstCastExpr *E);
+    void VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr *E);
+    void VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr *E);
+    void VisitCXXNullPtrLiteralExpr(CXXNullPtrLiteralExpr *E);
+    void VisitCXXTypeidExpr(CXXTypeidExpr *E);
+    void VisitCXXThisExpr(CXXThisExpr *E);
+    void VisitCXXThrowExpr(CXXThrowExpr *E);
+    void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E);
+    void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E);
     
-    unsigned VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E);
-    unsigned VisitCXXNewExpr(CXXNewExpr *E);
-    unsigned VisitCXXDeleteExpr(CXXDeleteExpr *E);
-    unsigned VisitCXXPseudoDestructorExpr(CXXPseudoDestructorExpr *E);
+    void VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E);
+    void VisitCXXNewExpr(CXXNewExpr *E);
+    void VisitCXXDeleteExpr(CXXDeleteExpr *E);
+    void VisitCXXPseudoDestructorExpr(CXXPseudoDestructorExpr *E);
     
-    unsigned VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E);
+    void VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E);
     
-    unsigned VisitCXXDependentScopeMemberExpr(CXXDependentScopeMemberExpr *E);
-    unsigned VisitDependentScopeDeclRefExpr(DependentScopeDeclRefExpr *E);
-    unsigned VisitCXXUnresolvedConstructExpr(CXXUnresolvedConstructExpr *E);
-
-    unsigned VisitOverloadExpr(OverloadExpr *E);
-    unsigned VisitUnresolvedMemberExpr(UnresolvedMemberExpr *E);
-    unsigned VisitUnresolvedLookupExpr(UnresolvedLookupExpr *E);
+    void VisitCXXDependentScopeMemberExpr(CXXDependentScopeMemberExpr *E);
+    void VisitDependentScopeDeclRefExpr(DependentScopeDeclRefExpr *E);
+    void VisitCXXUnresolvedConstructExpr(CXXUnresolvedConstructExpr *E);
+
+    void VisitOverloadExpr(OverloadExpr *E);
+    void VisitUnresolvedMemberExpr(UnresolvedMemberExpr *E);
+    void VisitUnresolvedLookupExpr(UnresolvedLookupExpr *E);
   };
 }
 
-unsigned PCHStmtReader::
+void PCHStmtReader::
 ReadExplicitTemplateArgumentList(ExplicitTemplateArgumentList &ArgList,
-                                 unsigned NumTemplateArgs,
-                           llvm::SmallVectorImpl<Stmt *>::iterator EndOfExprs) {
-
-  class StmtStackExprReader : public PCHReader::ExprReader {
-    llvm::SmallVectorImpl<Stmt *>::iterator StmtI;
-  public:
-    StmtStackExprReader(const llvm::SmallVectorImpl<Stmt *>::iterator &stmtI)
-      : StmtI(stmtI) { }
-    virtual Expr *Read() { return cast_or_null<Expr>(*StmtI++); }
-  };
-
-  unsigned NumExprs = Record[Idx++];
-  
+                                 unsigned NumTemplateArgs) {
   TemplateArgumentListInfo ArgInfo;
   ArgInfo.setLAngleLoc(Reader.ReadSourceLocation(Record, Idx));
   ArgInfo.setRAngleLoc(Reader.ReadSourceLocation(Record, Idx));
-  
-  StmtStackExprReader ExprReader(EndOfExprs - NumExprs);
   for (unsigned i = 0; i != NumTemplateArgs; ++i)
-    ArgInfo.addArgument(Reader.ReadTemplateArgumentLoc(Record, Idx,
-                                                       ExprReader));
+    ArgInfo.addArgument(Reader.ReadTemplateArgumentLoc(Record, Idx));
   ArgList.initializeFrom(ArgInfo);
-
-  return NumExprs;
 }
 
-unsigned PCHStmtReader::VisitStmt(Stmt *S) {
+void PCHStmtReader::VisitStmt(Stmt *S) {
   assert(Idx == NumStmtFields && "Incorrect statement field count");
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitNullStmt(NullStmt *S) {
+void PCHStmtReader::VisitNullStmt(NullStmt *S) {
   VisitStmt(S);
   S->setSemiLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitCompoundStmt(CompoundStmt *S) {
+void PCHStmtReader::VisitCompoundStmt(CompoundStmt *S) {
   VisitStmt(S);
+  llvm::SmallVector<Stmt *, 16> Stmts;
   unsigned NumStmts = Record[Idx++];
-  S->setStmts(*Reader.getContext(),
-              StmtStack.data() + StmtStack.size() - NumStmts, NumStmts);
+  while (NumStmts--)
+    Stmts.push_back(Reader.ReadStmt());
+  S->setStmts(*Reader.getContext(), Stmts.data(), Stmts.size());
   S->setLBracLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setRBracLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return NumStmts;
 }
 
-unsigned PCHStmtReader::VisitSwitchCase(SwitchCase *S) {
+void PCHStmtReader::VisitSwitchCase(SwitchCase *S) {
   VisitStmt(S);
   Reader.RecordSwitchCaseID(S, Record[Idx++]);
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitCaseStmt(CaseStmt *S) {
+void PCHStmtReader::VisitCaseStmt(CaseStmt *S) {
   VisitSwitchCase(S);
-  S->setLHS(cast<Expr>(StmtStack[StmtStack.size() - 3]));
-  S->setRHS(cast_or_null<Expr>(StmtStack[StmtStack.size() - 2]));
-  S->setSubStmt(StmtStack.back());
+  S->setLHS(Reader.ReadExpr());
+  S->setRHS(Reader.ReadExpr());
+  S->setSubStmt(Reader.ReadStmt());
   S->setCaseLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setEllipsisLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setColonLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 3;
 }
 
-unsigned PCHStmtReader::VisitDefaultStmt(DefaultStmt *S) {
+void PCHStmtReader::VisitDefaultStmt(DefaultStmt *S) {
   VisitSwitchCase(S);
-  S->setSubStmt(StmtStack.back());
+  S->setSubStmt(Reader.ReadStmt());
   S->setDefaultLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setColonLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitLabelStmt(LabelStmt *S) {
+void PCHStmtReader::VisitLabelStmt(LabelStmt *S) {
   VisitStmt(S);
   S->setID(Reader.GetIdentifierInfo(Record, Idx));
-  S->setSubStmt(StmtStack.back());
+  S->setSubStmt(Reader.ReadStmt());
   S->setIdentLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   Reader.RecordLabelStmt(S, Record[Idx++]);
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitIfStmt(IfStmt *S) {
+void PCHStmtReader::VisitIfStmt(IfStmt *S) {
   VisitStmt(S);
   S->setConditionVariable(*Reader.getContext(),
                           cast_or_null<VarDecl>(Reader.GetDecl(Record[Idx++])));
-  S->setCond(cast<Expr>(StmtStack[StmtStack.size() - 3]));
-  S->setThen(StmtStack[StmtStack.size() - 2]);
-  S->setElse(StmtStack[StmtStack.size() - 1]);
+  S->setCond(Reader.ReadExpr());
+  S->setThen(Reader.ReadStmt());
+  S->setElse(Reader.ReadStmt());
   S->setIfLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setElseLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 3;
 }
 
-unsigned PCHStmtReader::VisitSwitchStmt(SwitchStmt *S) {
+void PCHStmtReader::VisitSwitchStmt(SwitchStmt *S) {
   VisitStmt(S);
   S->setConditionVariable(*Reader.getContext(),
                           cast_or_null<VarDecl>(Reader.GetDecl(Record[Idx++])));
-  S->setCond(cast<Expr>(StmtStack[StmtStack.size() - 2]));
-  S->setBody(StmtStack.back());
+  S->setCond(Reader.ReadExpr());
+  S->setBody(Reader.ReadStmt());
   S->setSwitchLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   SwitchCase *PrevSC = 0;
   for (unsigned N = Record.size(); Idx != N; ++Idx) {
@@ -272,80 +240,71 @@
     SC->Retain();
     PrevSC = SC;
   }
-  return 2;
 }
 
-unsigned PCHStmtReader::VisitWhileStmt(WhileStmt *S) {
+void PCHStmtReader::VisitWhileStmt(WhileStmt *S) {
   VisitStmt(S);
   S->setConditionVariable(*Reader.getContext(),
                           cast_or_null<VarDecl>(Reader.GetDecl(Record[Idx++])));
-  S->setCond(cast_or_null<Expr>(StmtStack[StmtStack.size() - 2]));
-  S->setBody(StmtStack.back());
+  S->setCond(Reader.ReadExpr());
+  S->setBody(Reader.ReadStmt());
   S->setWhileLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 2;
 }
 
-unsigned PCHStmtReader::VisitDoStmt(DoStmt *S) {
+void PCHStmtReader::VisitDoStmt(DoStmt *S) {
   VisitStmt(S);
-  S->setCond(cast_or_null<Expr>(StmtStack[StmtStack.size() - 2]));
-  S->setBody(StmtStack.back());
+  S->setCond(Reader.ReadExpr());
+  S->setBody(Reader.ReadStmt());
   S->setDoLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setWhileLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 2;
 }
 
-unsigned PCHStmtReader::VisitForStmt(ForStmt *S) {
+void PCHStmtReader::VisitForStmt(ForStmt *S) {
   VisitStmt(S);
-  S->setInit(StmtStack[StmtStack.size() - 4]);
-  S->setCond(cast_or_null<Expr>(StmtStack[StmtStack.size() - 3]));
+  S->setInit(Reader.ReadStmt());
+  S->setCond(Reader.ReadExpr());
   S->setConditionVariable(*Reader.getContext(),
                           cast_or_null<VarDecl>(Reader.GetDecl(Record[Idx++])));
-  S->setInc(cast_or_null<Expr>(StmtStack[StmtStack.size() - 2]));
-  S->setBody(StmtStack.back());
+  S->setInc(Reader.ReadExpr());
+  S->setBody(Reader.ReadStmt());
   S->setForLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setLParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 4;
 }
 
-unsigned PCHStmtReader::VisitGotoStmt(GotoStmt *S) {
+void PCHStmtReader::VisitGotoStmt(GotoStmt *S) {
   VisitStmt(S);
   Reader.SetLabelOf(S, Record[Idx++]);
   S->setGotoLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setLabelLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitIndirectGotoStmt(IndirectGotoStmt *S) {
+void PCHStmtReader::VisitIndirectGotoStmt(IndirectGotoStmt *S) {
   VisitStmt(S);
   S->setGotoLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setStarLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  S->setTarget(cast_or_null<Expr>(StmtStack.back()));
-  return 1;
+  S->setTarget(Reader.ReadExpr());
 }
 
-unsigned PCHStmtReader::VisitContinueStmt(ContinueStmt *S) {
+void PCHStmtReader::VisitContinueStmt(ContinueStmt *S) {
   VisitStmt(S);
   S->setContinueLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitBreakStmt(BreakStmt *S) {
+void PCHStmtReader::VisitBreakStmt(BreakStmt *S) {
   VisitStmt(S);
   S->setBreakLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitReturnStmt(ReturnStmt *S) {
+void PCHStmtReader::VisitReturnStmt(ReturnStmt *S) {
   VisitStmt(S);
-  S->setRetValue(cast_or_null<Expr>(StmtStack.back()));
+  S->setRetValue(Reader.ReadExpr());
   S->setReturnLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setNRVOCandidate(cast_or_null<VarDecl>(Reader.GetDecl(Record[Idx++])));
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitDeclStmt(DeclStmt *S) {
+void PCHStmtReader::VisitDeclStmt(DeclStmt *S) {
   VisitStmt(S);
   S->setStartLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setEndLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
@@ -362,10 +321,9 @@
                                                    Decls.data(),
                                                    Decls.size())));
   }
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitAsmStmt(AsmStmt *S) {
+void PCHStmtReader::VisitAsmStmt(AsmStmt *S) {
   VisitStmt(S);
   unsigned NumOutputs = Record[Idx++];
   unsigned NumInputs = Record[Idx++];
@@ -376,9 +334,7 @@
   S->setSimple(Record[Idx++]);
   S->setMSAsm(Record[Idx++]);
 
-  unsigned StackIdx
-    = StmtStack.size() - (NumOutputs*2 + NumInputs*2 + NumClobbers + 1);
-  S->setAsmString(cast_or_null<StringLiteral>(StmtStack[StackIdx++]));
+  S->setAsmString(cast_or_null<StringLiteral>(Reader.ReadStmt()));
 
   // Outputs and inputs
   llvm::SmallVector<IdentifierInfo *, 16> Names;
@@ -386,71 +342,62 @@
   llvm::SmallVector<Stmt*, 16> Exprs;
   for (unsigned I = 0, N = NumOutputs + NumInputs; I != N; ++I) {
     Names.push_back(Reader.GetIdentifierInfo(Record, Idx));
-    Constraints.push_back(cast_or_null<StringLiteral>(StmtStack[StackIdx++]));
-    Exprs.push_back(StmtStack[StackIdx++]);
+    Constraints.push_back(cast_or_null<StringLiteral>(Reader.ReadStmt()));
+    Exprs.push_back(Reader.ReadStmt());
   }
 
   // Constraints
   llvm::SmallVector<StringLiteral*, 16> Clobbers;
   for (unsigned I = 0; I != NumClobbers; ++I)
-    Clobbers.push_back(cast_or_null<StringLiteral>(StmtStack[StackIdx++]));
+    Clobbers.push_back(cast_or_null<StringLiteral>(Reader.ReadStmt()));
 
   S->setOutputsAndInputsAndClobbers(*Reader.getContext(),
                                     Names.data(), Constraints.data(), 
                                     Exprs.data(), NumOutputs, NumInputs, 
                                     Clobbers.data(), NumClobbers);
-
-  assert(StackIdx == StmtStack.size() && "Error deserializing AsmStmt");
-  return NumOutputs*2 + NumInputs*2 + NumClobbers + 1;
 }
 
-unsigned PCHStmtReader::VisitExpr(Expr *E) {
+void PCHStmtReader::VisitExpr(Expr *E) {
   VisitStmt(E);
   E->setType(Reader.GetType(Record[Idx++]));
   E->setTypeDependent(Record[Idx++]);
   E->setValueDependent(Record[Idx++]);
   assert(Idx == NumExprFields && "Incorrect expression field count");
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitPredefinedExpr(PredefinedExpr *E) {
+void PCHStmtReader::VisitPredefinedExpr(PredefinedExpr *E) {
   VisitExpr(E);
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setIdentType((PredefinedExpr::IdentType)Record[Idx++]);
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitDeclRefExpr(DeclRefExpr *E) {
+void PCHStmtReader::VisitDeclRefExpr(DeclRefExpr *E) {
   VisitExpr(E);
   E->setDecl(cast<ValueDecl>(Reader.GetDecl(Record[Idx++])));
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
   // FIXME: read qualifier
   // FIXME: read explicit template arguments
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitIntegerLiteral(IntegerLiteral *E) {
+void PCHStmtReader::VisitIntegerLiteral(IntegerLiteral *E) {
   VisitExpr(E);
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setValue(Reader.ReadAPInt(Record, Idx));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitFloatingLiteral(FloatingLiteral *E) {
+void PCHStmtReader::VisitFloatingLiteral(FloatingLiteral *E) {
   VisitExpr(E);
   E->setValue(Reader.ReadAPFloat(Record, Idx));
   E->setExact(Record[Idx++]);
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitImaginaryLiteral(ImaginaryLiteral *E) {
+void PCHStmtReader::VisitImaginaryLiteral(ImaginaryLiteral *E) {
   VisitExpr(E);
-  E->setSubExpr(cast<Expr>(StmtStack.back()));
-  return 1;
+  E->setSubExpr(Reader.ReadExpr());
 }
 
-unsigned PCHStmtReader::VisitStringLiteral(StringLiteral *E) {
+void PCHStmtReader::VisitStringLiteral(StringLiteral *E) {
   VisitExpr(E);
   unsigned Len = Record[Idx++];
   assert(Record[Idx] == E->getNumConcatenated() &&
@@ -466,35 +413,30 @@
   // Read source locations
   for (unsigned I = 0, N = E->getNumConcatenated(); I != N; ++I)
     E->setStrTokenLoc(I, SourceLocation::getFromRawEncoding(Record[Idx++]));
-
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitCharacterLiteral(CharacterLiteral *E) {
+void PCHStmtReader::VisitCharacterLiteral(CharacterLiteral *E) {
   VisitExpr(E);
   E->setValue(Record[Idx++]);
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setWide(Record[Idx++]);
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitParenExpr(ParenExpr *E) {
+void PCHStmtReader::VisitParenExpr(ParenExpr *E) {
   VisitExpr(E);
   E->setLParen(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParen(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  E->setSubExpr(cast<Expr>(StmtStack.back()));
-  return 1;
+  E->setSubExpr(Reader.ReadExpr());
 }
 
-unsigned PCHStmtReader::VisitUnaryOperator(UnaryOperator *E) {
+void PCHStmtReader::VisitUnaryOperator(UnaryOperator *E) {
   VisitExpr(E);
-  E->setSubExpr(cast<Expr>(StmtStack.back()));
+  E->setSubExpr(Reader.ReadExpr());
   E->setOpcode((UnaryOperator::Opcode)Record[Idx++]);
   E->setOperatorLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitOffsetOfExpr(OffsetOfExpr *E) {
+void PCHStmtReader::VisitOffsetOfExpr(OffsetOfExpr *E) {
   typedef OffsetOfExpr::OffsetOfNode Node;
   VisitExpr(E);
   assert(E->getNumComponents() == Record[Idx]);
@@ -532,153 +474,135 @@
   }
   
   for (unsigned I = 0, N = E->getNumExpressions(); I != N; ++I)
-    E->setIndexExpr(I, cast_or_null<Expr>(StmtStack[StmtStack.size() - N + I]));
-  
-  return E->getNumExpressions();
+    E->setIndexExpr(I, Reader.ReadExpr());
 }
 
-unsigned PCHStmtReader::VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E) {
+void PCHStmtReader::VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E) {
   VisitExpr(E);
   E->setSizeof(Record[Idx++]);
   if (Record[Idx] == 0) {
-    E->setArgument(cast<Expr>(StmtStack.back()));
+    E->setArgument(Reader.ReadExpr());
     ++Idx;
   } else {
     E->setArgument(Reader.GetTypeSourceInfo(Record, Idx));
   }
   E->setOperatorLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return E->isArgumentType()? 0 : 1;
 }
 
-unsigned PCHStmtReader::VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
+void PCHStmtReader::VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
   VisitExpr(E);
-  E->setLHS(cast<Expr>(StmtStack[StmtStack.size() - 2]));
-  E->setRHS(cast<Expr>(StmtStack[StmtStack.size() - 1]));
+  E->setLHS(Reader.ReadExpr());
+  E->setRHS(Reader.ReadExpr());
   E->setRBracketLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 2;
 }
 
-unsigned PCHStmtReader::VisitCallExpr(CallExpr *E) {
+void PCHStmtReader::VisitCallExpr(CallExpr *E) {
   VisitExpr(E);
   E->setNumArgs(*Reader.getContext(), Record[Idx++]);
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  E->setCallee(cast<Expr>(StmtStack[StmtStack.size() - E->getNumArgs() - 1]));
+  E->setCallee(Reader.ReadExpr());
   for (unsigned I = 0, N = E->getNumArgs(); I != N; ++I)
-    E->setArg(I, cast<Expr>(StmtStack[StmtStack.size() - N + I]));
-  return E->getNumArgs() + 1;
+    E->setArg(I, Reader.ReadExpr());
 }
 
-unsigned PCHStmtReader::VisitMemberExpr(MemberExpr *E) {
+void PCHStmtReader::VisitMemberExpr(MemberExpr *E) {
   VisitExpr(E);
-  E->setBase(cast<Expr>(StmtStack.back()));
+  E->setBase(Reader.ReadExpr());
   E->setMemberDecl(cast<ValueDecl>(Reader.GetDecl(Record[Idx++])));
   E->setMemberLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setArrow(Record[Idx++]);
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitObjCIsaExpr(ObjCIsaExpr *E) {
+void PCHStmtReader::VisitObjCIsaExpr(ObjCIsaExpr *E) {
   VisitExpr(E);
-  E->setBase(cast<Expr>(StmtStack.back()));
+  E->setBase(Reader.ReadExpr());
   E->setIsaMemberLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setArrow(Record[Idx++]);
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitCastExpr(CastExpr *E) {
+void PCHStmtReader::VisitCastExpr(CastExpr *E) {
   VisitExpr(E);
-  E->setSubExpr(cast<Expr>(StmtStack.back()));
+  E->setSubExpr(Reader.ReadExpr());
   E->setCastKind((CastExpr::CastKind)Record[Idx++]);
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitBinaryOperator(BinaryOperator *E) {
+void PCHStmtReader::VisitBinaryOperator(BinaryOperator *E) {
   VisitExpr(E);
-  E->setLHS(cast<Expr>(StmtStack.end()[-2]));
-  E->setRHS(cast<Expr>(StmtStack.end()[-1]));
+  E->setLHS(Reader.ReadExpr());
+  E->setRHS(Reader.ReadExpr());
   E->setOpcode((BinaryOperator::Opcode)Record[Idx++]);
   E->setOperatorLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 2;
 }
 
-unsigned PCHStmtReader::VisitCompoundAssignOperator(CompoundAssignOperator *E) {
+void PCHStmtReader::VisitCompoundAssignOperator(CompoundAssignOperator *E) {
   VisitBinaryOperator(E);
   E->setComputationLHSType(Reader.GetType(Record[Idx++]));
   E->setComputationResultType(Reader.GetType(Record[Idx++]));
-  return 2;
 }
 
-unsigned PCHStmtReader::VisitConditionalOperator(ConditionalOperator *E) {
+void PCHStmtReader::VisitConditionalOperator(ConditionalOperator *E) {
   VisitExpr(E);
-  E->setCond(cast<Expr>(StmtStack[StmtStack.size() - 3]));
-  E->setLHS(cast_or_null<Expr>(StmtStack[StmtStack.size() - 2]));
-  E->setRHS(cast_or_null<Expr>(StmtStack[StmtStack.size() - 1]));
+  E->setCond(Reader.ReadExpr());
+  E->setLHS(Reader.ReadExpr());
+  E->setRHS(Reader.ReadExpr());
   E->setQuestionLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setColonLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 3;
 }
 
-unsigned PCHStmtReader::VisitImplicitCastExpr(ImplicitCastExpr *E) {
+void PCHStmtReader::VisitImplicitCastExpr(ImplicitCastExpr *E) {
   VisitCastExpr(E);
   E->setLvalueCast(Record[Idx++]);
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitExplicitCastExpr(ExplicitCastExpr *E) {
+void PCHStmtReader::VisitExplicitCastExpr(ExplicitCastExpr *E) {
   VisitCastExpr(E);
   E->setTypeInfoAsWritten(Reader.GetTypeSourceInfo(Record, Idx));
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitCStyleCastExpr(CStyleCastExpr *E) {
+void PCHStmtReader::VisitCStyleCastExpr(CStyleCastExpr *E) {
   VisitExplicitCastExpr(E);
   E->setLParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
+void PCHStmtReader::VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
   VisitExpr(E);
   E->setLParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setTypeSourceInfo(Reader.GetTypeSourceInfo(Record, Idx));
-  E->setInitializer(cast<Expr>(StmtStack.back()));
+  E->setInitializer(Reader.ReadExpr());
   E->setFileScope(Record[Idx++]);
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitExtVectorElementExpr(ExtVectorElementExpr *E) {
+void PCHStmtReader::VisitExtVectorElementExpr(ExtVectorElementExpr *E) {
   VisitExpr(E);
-  E->setBase(cast<Expr>(StmtStack.back()));
+  E->setBase(Reader.ReadExpr());
   E->setAccessor(Reader.GetIdentifierInfo(Record, Idx));
   E->setAccessorLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitInitListExpr(InitListExpr *E) {
+void PCHStmtReader::VisitInitListExpr(InitListExpr *E) {
   VisitExpr(E);
   unsigned NumInits = Record[Idx++];
   E->reserveInits(*Reader.getContext(), NumInits);
   for (unsigned I = 0; I != NumInits; ++I)
-    E->updateInit(*Reader.getContext(), I,
-                  cast<Expr>(StmtStack[StmtStack.size() - NumInits - 1 + I]));
-  E->setSyntacticForm(cast_or_null<InitListExpr>(StmtStack.back()));
+    E->updateInit(*Reader.getContext(), I, Reader.ReadExpr());
+  E->setSyntacticForm(cast_or_null<InitListExpr>(Reader.ReadStmt()));
   E->setLBraceLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRBraceLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setInitializedFieldInUnion(
                       cast_or_null<FieldDecl>(Reader.GetDecl(Record[Idx++])));
   E->sawArrayRangeDesignator(Record[Idx++]);
-  return NumInits + 1;
 }
 
-unsigned PCHStmtReader::VisitDesignatedInitExpr(DesignatedInitExpr *E) {
+void PCHStmtReader::VisitDesignatedInitExpr(DesignatedInitExpr *E) {
   typedef DesignatedInitExpr::Designator Designator;
 
   VisitExpr(E);
   unsigned NumSubExprs = Record[Idx++];
   assert(NumSubExprs == E->getNumSubExprs() && "Wrong number of subexprs");
   for (unsigned I = 0; I != NumSubExprs; ++I)
-    E->setSubExpr(I, cast<Expr>(StmtStack[StmtStack.size() - NumSubExprs + I]));
+    E->setSubExpr(I, Reader.ReadExpr());
   E->setEqualOrColonLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setGNUSyntax(Record[Idx++]);
 
@@ -733,144 +657,128 @@
   }
   E->setDesignators(*Reader.getContext(), 
                     Designators.data(), Designators.size());
-
-  return NumSubExprs;
 }
 
-unsigned PCHStmtReader::VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
+void PCHStmtReader::VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
   VisitExpr(E);
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitVAArgExpr(VAArgExpr *E) {
+void PCHStmtReader::VisitVAArgExpr(VAArgExpr *E) {
   VisitExpr(E);
-  E->setSubExpr(cast<Expr>(StmtStack.back()));
+  E->setSubExpr(Reader.ReadExpr());
   E->setBuiltinLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitAddrLabelExpr(AddrLabelExpr *E) {
+void PCHStmtReader::VisitAddrLabelExpr(AddrLabelExpr *E) {
   VisitExpr(E);
   E->setAmpAmpLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setLabelLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   Reader.SetLabelOf(E, Record[Idx++]);
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitStmtExpr(StmtExpr *E) {
+void PCHStmtReader::VisitStmtExpr(StmtExpr *E) {
   VisitExpr(E);
   E->setLParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  E->setSubStmt(cast_or_null<CompoundStmt>(StmtStack.back()));
-  return 1;
+  E->setSubStmt(cast_or_null<CompoundStmt>(Reader.ReadStmt()));
 }
 
-unsigned PCHStmtReader::VisitTypesCompatibleExpr(TypesCompatibleExpr *E) {
+void PCHStmtReader::VisitTypesCompatibleExpr(TypesCompatibleExpr *E) {
   VisitExpr(E);
   E->setArgType1(Reader.GetType(Record[Idx++]));
   E->setArgType2(Reader.GetType(Record[Idx++]));
   E->setBuiltinLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitChooseExpr(ChooseExpr *E) {
+void PCHStmtReader::VisitChooseExpr(ChooseExpr *E) {
   VisitExpr(E);
-  E->setCond(cast<Expr>(StmtStack[StmtStack.size() - 3]));
-  E->setLHS(cast_or_null<Expr>(StmtStack[StmtStack.size() - 2]));
-  E->setRHS(cast_or_null<Expr>(StmtStack[StmtStack.size() - 1]));
+  E->setCond(Reader.ReadExpr());
+  E->setLHS(Reader.ReadExpr());
+  E->setRHS(Reader.ReadExpr());
   E->setBuiltinLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 3;
 }
 
-unsigned PCHStmtReader::VisitGNUNullExpr(GNUNullExpr *E) {
+void PCHStmtReader::VisitGNUNullExpr(GNUNullExpr *E) {
   VisitExpr(E);
   E->setTokenLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitShuffleVectorExpr(ShuffleVectorExpr *E) {
+void PCHStmtReader::VisitShuffleVectorExpr(ShuffleVectorExpr *E) {
   VisitExpr(E);
+  llvm::SmallVector<Expr *, 16> Exprs;
   unsigned NumExprs = Record[Idx++];
-  E->setExprs(*Reader.getContext(),
-              (Expr **)&StmtStack[StmtStack.size() - NumExprs], NumExprs);
+  while (NumExprs--)
+    Exprs.push_back(Reader.ReadExpr());
+  E->setExprs(*Reader.getContext(), Exprs.data(), Exprs.size());
   E->setBuiltinLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return NumExprs;
 }
 
-unsigned PCHStmtReader::VisitBlockExpr(BlockExpr *E) {
+void PCHStmtReader::VisitBlockExpr(BlockExpr *E) {
   VisitExpr(E);
   E->setBlockDecl(cast_or_null<BlockDecl>(Reader.GetDecl(Record[Idx++])));
   E->setHasBlockDeclRefExprs(Record[Idx++]);
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitBlockDeclRefExpr(BlockDeclRefExpr *E) {
+void PCHStmtReader::VisitBlockDeclRefExpr(BlockDeclRefExpr *E) {
   VisitExpr(E);
   E->setDecl(cast<ValueDecl>(Reader.GetDecl(Record[Idx++])));
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setByRef(Record[Idx++]);
   E->setConstQualAdded(Record[Idx++]);
-  E->setCopyConstructorExpr(cast_or_null<Expr>(StmtStack.back()));
-  return 1;
+  E->setCopyConstructorExpr(Reader.ReadExpr());
 }
 
 //===----------------------------------------------------------------------===//
 // Objective-C Expressions and Statements
 
-unsigned PCHStmtReader::VisitObjCStringLiteral(ObjCStringLiteral *E) {
+void PCHStmtReader::VisitObjCStringLiteral(ObjCStringLiteral *E) {
   VisitExpr(E);
-  E->setString(cast<StringLiteral>(StmtStack.back()));
+  E->setString(cast<StringLiteral>(Reader.ReadStmt()));
   E->setAtLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitObjCEncodeExpr(ObjCEncodeExpr *E) {
+void PCHStmtReader::VisitObjCEncodeExpr(ObjCEncodeExpr *E) {
   VisitExpr(E);
   E->setEncodedTypeSourceInfo(Reader.GetTypeSourceInfo(Record, Idx));
   E->setAtLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitObjCSelectorExpr(ObjCSelectorExpr *E) {
+void PCHStmtReader::VisitObjCSelectorExpr(ObjCSelectorExpr *E) {
   VisitExpr(E);
   E->setSelector(Reader.GetSelector(Record, Idx));
   E->setAtLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitObjCProtocolExpr(ObjCProtocolExpr *E) {
+void PCHStmtReader::VisitObjCProtocolExpr(ObjCProtocolExpr *E) {
   VisitExpr(E);
   E->setProtocol(cast<ObjCProtocolDecl>(Reader.GetDecl(Record[Idx++])));
   E->setAtLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
+void PCHStmtReader::VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
   VisitExpr(E);
   E->setDecl(cast<ObjCIvarDecl>(Reader.GetDecl(Record[Idx++])));
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  E->setBase(cast<Expr>(StmtStack.back()));
+  E->setBase(Reader.ReadExpr());
   E->setIsArrow(Record[Idx++]);
   E->setIsFreeIvar(Record[Idx++]);
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) {
+void PCHStmtReader::VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) {
   VisitExpr(E);
   E->setProperty(cast<ObjCPropertyDecl>(Reader.GetDecl(Record[Idx++])));
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  E->setBase(cast<Expr>(StmtStack.back()));
-  return 1;
+  E->setBase(Reader.ReadExpr());
 }
 
-unsigned PCHStmtReader::VisitObjCImplicitSetterGetterRefExpr(
+void PCHStmtReader::VisitObjCImplicitSetterGetterRefExpr(
                                       ObjCImplicitSetterGetterRefExpr *E) {
   VisitExpr(E);
   E->setGetterMethod(
@@ -879,13 +787,12 @@
                  cast_or_null<ObjCMethodDecl>(Reader.GetDecl(Record[Idx++])));
   E->setInterfaceDecl(
               cast_or_null<ObjCInterfaceDecl>(Reader.GetDecl(Record[Idx++])));
-  E->setBase(cast_or_null<Expr>(StmtStack.back()));
+  E->setBase(Reader.ReadExpr());
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setClassLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitObjCMessageExpr(ObjCMessageExpr *E) {
+void PCHStmtReader::VisitObjCMessageExpr(ObjCMessageExpr *E) {
   VisitExpr(E);
   assert(Record[Idx] == E->getNumArgs());
   ++Idx;
@@ -893,8 +800,7 @@
     = static_cast<ObjCMessageExpr::ReceiverKind>(Record[Idx++]);
   switch (Kind) {
   case ObjCMessageExpr::Instance:
-    E->setInstanceReceiver(
-         cast_or_null<Expr>(StmtStack[StmtStack.size() - E->getNumArgs() - 1]));
+    E->setInstanceReceiver(Reader.ReadExpr());
     break;
 
   case ObjCMessageExpr::Class:
@@ -921,193 +827,168 @@
   E->setRightLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
 
   for (unsigned I = 0, N = E->getNumArgs(); I != N; ++I)
-    E->setArg(I, cast<Expr>(StmtStack[StmtStack.size() - N + I]));
-  return E->getNumArgs() + (Kind == ObjCMessageExpr::Instance);
+    E->setArg(I, Reader.ReadExpr());
 }
 
-unsigned PCHStmtReader::VisitObjCSuperExpr(ObjCSuperExpr *E) {
+void PCHStmtReader::VisitObjCSuperExpr(ObjCSuperExpr *E) {
   VisitExpr(E);
   E->setLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitObjCForCollectionStmt(ObjCForCollectionStmt *S) {
+void PCHStmtReader::VisitObjCForCollectionStmt(ObjCForCollectionStmt *S) {
   VisitStmt(S);
-  S->setElement(cast_or_null<Stmt>(StmtStack[StmtStack.size() - 3]));
-  S->setCollection(cast_or_null<Expr>(StmtStack[StmtStack.size() - 2]));
-  S->setBody(cast_or_null<Stmt>(StmtStack[StmtStack.size() - 1]));
+  S->setElement(Reader.ReadStmt());
+  S->setCollection(Reader.ReadExpr());
+  S->setBody(Reader.ReadStmt());
   S->setForLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 3;
 }
 
-unsigned PCHStmtReader::VisitObjCAtCatchStmt(ObjCAtCatchStmt *S) {
+void PCHStmtReader::VisitObjCAtCatchStmt(ObjCAtCatchStmt *S) {
   VisitStmt(S);
-  S->setCatchBody(cast_or_null<Stmt>(StmtStack.back()));
+  S->setCatchBody(Reader.ReadStmt());
   S->setCatchParamDecl(cast_or_null<VarDecl>(Reader.GetDecl(Record[Idx++])));
   S->setAtCatchLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   S->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitObjCAtFinallyStmt(ObjCAtFinallyStmt *S) {
+void PCHStmtReader::VisitObjCAtFinallyStmt(ObjCAtFinallyStmt *S) {
   VisitStmt(S);
-  S->setFinallyBody(StmtStack.back());
+  S->setFinallyBody(Reader.ReadStmt());
   S->setAtFinallyLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitObjCAtTryStmt(ObjCAtTryStmt *S) {
+void PCHStmtReader::VisitObjCAtTryStmt(ObjCAtTryStmt *S) {
   VisitStmt(S);
   assert(Record[Idx] == S->getNumCatchStmts());
   ++Idx;
   bool HasFinally = Record[Idx++];
-  for (unsigned I = 0, N = S->getNumCatchStmts(); I != N; ++I) {
-    unsigned Offset = StmtStack.size() - N - HasFinally + I;
-    S->setCatchStmt(I, cast_or_null<ObjCAtCatchStmt>(StmtStack[Offset]));
-  }
+  S->setTryBody(Reader.ReadStmt());
+  for (unsigned I = 0, N = S->getNumCatchStmts(); I != N; ++I)
+    S->setCatchStmt(I, cast_or_null<ObjCAtCatchStmt>(Reader.ReadStmt()));
 
-  unsigned TryOffset
-    = StmtStack.size() - S->getNumCatchStmts() - HasFinally - 1;
-  S->setTryBody(cast_or_null<Stmt>(StmtStack[TryOffset]));
   if (HasFinally)
-    S->setFinallyStmt(cast_or_null<Stmt>(StmtStack[StmtStack.size() - 1]));
+    S->setFinallyStmt(Reader.ReadStmt());
   S->setAtTryLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1 + S->getNumCatchStmts() + HasFinally;
 }
 
-unsigned PCHStmtReader::VisitObjCAtSynchronizedStmt(ObjCAtSynchronizedStmt *S) {
+void PCHStmtReader::VisitObjCAtSynchronizedStmt(ObjCAtSynchronizedStmt *S) {
   VisitStmt(S);
-  S->setSynchExpr(cast_or_null<Stmt>(StmtStack[StmtStack.size() - 2]));
-  S->setSynchBody(cast_or_null<Stmt>(StmtStack[StmtStack.size() - 1]));
+  S->setSynchExpr(Reader.ReadStmt());
+  S->setSynchBody(Reader.ReadStmt());
   S->setAtSynchronizedLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 2;
 }
 
-unsigned PCHStmtReader::VisitObjCAtThrowStmt(ObjCAtThrowStmt *S) {
+void PCHStmtReader::VisitObjCAtThrowStmt(ObjCAtThrowStmt *S) {
   VisitStmt(S);
-  S->setThrowExpr(StmtStack.back());
+  S->setThrowExpr(Reader.ReadStmt());
   S->setThrowLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1;
 }
 
 //===----------------------------------------------------------------------===//
 // C++ Expressions and Statements
 
-unsigned PCHStmtReader::VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
-  unsigned num = VisitCallExpr(E);
+void PCHStmtReader::VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
+  VisitCallExpr(E);
   E->setOperator((OverloadedOperatorKind)Record[Idx++]);
-  return num;
 }
 
-unsigned PCHStmtReader::VisitCXXConstructExpr(CXXConstructExpr *E) {
+void PCHStmtReader::VisitCXXConstructExpr(CXXConstructExpr *E) {
   VisitExpr(E);
-  assert(Record[Idx] == E->getNumArgs() &&
-         "Read wrong record during creation ?");
+  assert(Record[Idx] == E->getNumArgs() &&"Read wrong record during creation?");
   ++Idx; // NumArgs;
   for (unsigned I = 0, N = E->getNumArgs(); I != N; ++I)
-    E->setArg(I, cast<Expr>(StmtStack[StmtStack.size() - N + I]));
+    E->setArg(I, Reader.ReadExpr());
   E->setConstructor(cast<CXXConstructorDecl>(Reader.GetDecl(Record[Idx++])));
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setElidable(Record[Idx++]);  
   E->setRequiresZeroInitialization(Record[Idx++]);
   E->setConstructionKind((CXXConstructExpr::ConstructionKind)Record[Idx++]);
-  return E->getNumArgs();
 }
 
-unsigned PCHStmtReader::VisitCXXNamedCastExpr(CXXNamedCastExpr *E) {
-  unsigned num = VisitExplicitCastExpr(E);
+void PCHStmtReader::VisitCXXNamedCastExpr(CXXNamedCastExpr *E) {
+  VisitExplicitCastExpr(E);
   E->setOperatorLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return num;
 }
 
-unsigned PCHStmtReader::VisitCXXStaticCastExpr(CXXStaticCastExpr *E) {
+void PCHStmtReader::VisitCXXStaticCastExpr(CXXStaticCastExpr *E) {
   return VisitCXXNamedCastExpr(E);
 }
 
-unsigned PCHStmtReader::VisitCXXDynamicCastExpr(CXXDynamicCastExpr *E) {
+void PCHStmtReader::VisitCXXDynamicCastExpr(CXXDynamicCastExpr *E) {
   return VisitCXXNamedCastExpr(E);
 }
 
-unsigned PCHStmtReader::VisitCXXReinterpretCastExpr(CXXReinterpretCastExpr *E) {
+void PCHStmtReader::VisitCXXReinterpretCastExpr(CXXReinterpretCastExpr *E) {
   return VisitCXXNamedCastExpr(E);
 }
 
-unsigned PCHStmtReader::VisitCXXConstCastExpr(CXXConstCastExpr *E) {
+void PCHStmtReader::VisitCXXConstCastExpr(CXXConstCastExpr *E) {
   return VisitCXXNamedCastExpr(E);
 }
 
-unsigned PCHStmtReader::VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr *E) {
-  unsigned num = VisitExplicitCastExpr(E);
+void PCHStmtReader::VisitCXXFunctionalCastExpr(CXXFunctionalCastExpr *E) {
+  VisitExplicitCastExpr(E);
   E->setTypeBeginLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return num;
 }
 
-unsigned PCHStmtReader::VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr *E) {
+void PCHStmtReader::VisitCXXBoolLiteralExpr(CXXBoolLiteralExpr *E) {
   VisitExpr(E);
   E->setValue(Record[Idx++]);
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitCXXNullPtrLiteralExpr(CXXNullPtrLiteralExpr *E) {
+void PCHStmtReader::VisitCXXNullPtrLiteralExpr(CXXNullPtrLiteralExpr *E) {
   VisitExpr(E);
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitCXXTypeidExpr(CXXTypeidExpr *E) {
+void PCHStmtReader::VisitCXXTypeidExpr(CXXTypeidExpr *E) {
   VisitExpr(E);
   E->setSourceRange(Reader.ReadSourceRange(Record, Idx));
   if (E->isTypeOperand()) { // typeid(int)
     E->setTypeOperandSourceInfo(Reader.GetTypeSourceInfo(Record, Idx));
-    return 0;
+    return;
   }
   
   // typeid(42+2)
-  E->setExprOperand(cast<Expr>(StmtStack.back()));
-  return 1;
+  E->setExprOperand(Reader.ReadExpr());
 }
 
-unsigned PCHStmtReader::VisitCXXThisExpr(CXXThisExpr *E) {
+void PCHStmtReader::VisitCXXThisExpr(CXXThisExpr *E) {
   VisitExpr(E);
   E->setLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setImplicit(Record[Idx++]);
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitCXXThrowExpr(CXXThrowExpr *E) {
+void PCHStmtReader::VisitCXXThrowExpr(CXXThrowExpr *E) {
   VisitExpr(E);
   E->setThrowLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  E->setSubExpr(cast_or_null<Expr>(StmtStack.back()));
-  return 1;
+  E->setSubExpr(Reader.ReadExpr());
 }
 
-unsigned PCHStmtReader::VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
+void PCHStmtReader::VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
   VisitExpr(E);
   E->setUsedLocation(SourceLocation::getFromRawEncoding(Record[Idx++]));
   bool HasStoredExpr = Record[Idx++];
-  if (!HasStoredExpr) return 0;
-  E->setExpr(cast<Expr>(StmtStack.back()));
-  return 1;
+  if (!HasStoredExpr) return;
+  E->setExpr(Reader.ReadExpr());
 }
 
-unsigned PCHStmtReader::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) {
+void PCHStmtReader::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) {
   VisitExpr(E);
   E->setTemporary(Reader.ReadCXXTemporary(Record, Idx));
-  E->setSubExpr(cast<Expr>(StmtStack.back()));
-  return 1;
+  E->setSubExpr(Reader.ReadExpr());
 }
 
-unsigned PCHStmtReader::VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E) {
+void PCHStmtReader::VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E) {
   VisitExpr(E);
   E->setTypeBeginLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
   E->setRParenLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 0;
 }
 
-unsigned PCHStmtReader::VisitCXXNewExpr(CXXNewExpr *E) {
+void PCHStmtReader::VisitCXXNewExpr(CXXNewExpr *E) {
   VisitExpr(E);
   E->setGlobalNew(Record[Idx++]);
   E->setParenTypeId(Record[Idx++]);
@@ -1127,31 +1008,25 @@
                        NumCtorArgs);
 
   // Install all the subexpressions.
-  unsigned TotalSubExprs = E->raw_arg_end()-E->raw_arg_begin();
-  unsigned SSIdx = StmtStack.size()-TotalSubExprs;
   for (CXXNewExpr::raw_arg_iterator I = E->raw_arg_begin(),e = E->raw_arg_end();
        I != e; ++I)
-    *I = StmtStack[SSIdx++];
-  
-  return TotalSubExprs;
+    *I = Reader.ReadStmt();
 }
 
-unsigned PCHStmtReader::VisitCXXDeleteExpr(CXXDeleteExpr *E) {
+void PCHStmtReader::VisitCXXDeleteExpr(CXXDeleteExpr *E) {
   VisitExpr(E);
   E->setGlobalDelete(Record[Idx++]);
   E->setArrayForm(Record[Idx++]);
   E->setOperatorDelete(
                      cast_or_null<FunctionDecl>(Reader.GetDecl(Record[Idx++])));
-  E->setArgument(cast_or_null<Expr>(StmtStack.back()));
+  E->setArgument(Reader.ReadExpr());
   E->setStartLoc(SourceLocation::getFromRawEncoding(Record[Idx++]));
-  return 1;
 }
 
-unsigned
-PCHStmtReader::VisitCXXPseudoDestructorExpr(CXXPseudoDestructorExpr *E) {
+void PCHStmtReader::VisitCXXPseudoDestructorExpr(CXXPseudoDestructorExpr *E) {
   VisitExpr(E);
 
-  E->setBase(cast_or_null<Expr>(StmtStack.back()));
+  E->setBase(Reader.ReadExpr());
   E->setArrow(Record[Idx++]);
   E->setOperatorLoc(Reader.ReadSourceLocation(Record, Idx));
   E->setQualifier(Reader.ReadNestedNameSpecifier(Record, Idx));
@@ -1165,11 +1040,9 @@
     E->setDestroyedType(II, Reader.ReadSourceLocation(Record, Idx));
   else
     E->setDestroyedType(Reader.GetTypeSourceInfo(Record, Idx));
-  
-  return 1;
 }
 
-unsigned PCHStmtReader::VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) {
+void PCHStmtReader::VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) {
   VisitExpr(E);
   unsigned NumTemps = Record[Idx++];
   if (NumTemps) {
@@ -1177,24 +1050,21 @@
     for (unsigned i = 0; i != NumTemps; ++i)
       E->setTemporary(i, Reader.ReadCXXTemporary(Record, Idx));
   }
-  E->setSubExpr(cast<Expr>(StmtStack.back()));
-  return 1;
+  E->setSubExpr(Reader.ReadExpr());
 }
 
-unsigned
+void
 PCHStmtReader::VisitCXXDependentScopeMemberExpr(CXXDependentScopeMemberExpr *E){
   VisitExpr(E);
-  unsigned NumExprs = 0;
   
   unsigned NumTemplateArgs = Record[Idx++];
   assert((NumTemplateArgs != 0) == E->hasExplicitTemplateArgs() &&
          "Read wrong record during creation ?");
   if (E->hasExplicitTemplateArgs())
-    NumExprs
-      = ReadExplicitTemplateArgumentList(*E->getExplicitTemplateArgumentList(),
-                                         NumTemplateArgs, StmtStack.end());
+    ReadExplicitTemplateArgumentList(*E->getExplicitTemplateArgumentList(),
+                                     NumTemplateArgs);
 
-  E->setBase(cast_or_null<Expr>(StmtStack.back()));
+  E->setBase(Reader.ReadExpr());
   E->setBaseType(Reader.GetType(Record[Idx++]));
   E->setArrow(Record[Idx++]);
   E->setOperatorLoc(Reader.ReadSourceLocation(Record, Idx));
@@ -1204,58 +1074,47 @@
                         cast_or_null<NamedDecl>(Reader.GetDecl(Record[Idx++])));
   E->setMember(Reader.ReadDeclarationName(Record, Idx));
   E->setMemberLoc(Reader.ReadSourceLocation(Record, Idx));
-  
-  return NumExprs + 1;
 }
 
-unsigned
+void
 PCHStmtReader::VisitDependentScopeDeclRefExpr(DependentScopeDeclRefExpr *E) {
   VisitExpr(E);
-  unsigned NumExprs = 0;
   
   unsigned NumTemplateArgs = Record[Idx++];
   assert((NumTemplateArgs != 0) == E->hasExplicitTemplateArgs() &&
          "Read wrong record during creation ?");
   if (E->hasExplicitTemplateArgs())
-    NumExprs
-      = ReadExplicitTemplateArgumentList(E->getExplicitTemplateArgs(),
-                                         NumTemplateArgs, StmtStack.end());
+    ReadExplicitTemplateArgumentList(E->getExplicitTemplateArgs(),
+                                     NumTemplateArgs);
 
   E->setDeclName(Reader.ReadDeclarationName(Record, Idx));
   E->setLocation(Reader.ReadSourceLocation(Record, Idx));
   E->setQualifierRange(Reader.ReadSourceRange(Record, Idx));
   E->setQualifier(Reader.ReadNestedNameSpecifier(Record, Idx));
-  return NumExprs;
 }
 
-unsigned
+void
 PCHStmtReader::VisitCXXUnresolvedConstructExpr(CXXUnresolvedConstructExpr *E) {
   VisitExpr(E);
   assert(Record[Idx] == E->arg_size() && "Read wrong record during creation ?");
   ++Idx; // NumArgs;
   for (unsigned I = 0, N = E->arg_size(); I != N; ++I)
-    E->setArg(I, cast<Expr>(StmtStack[StmtStack.size() - N + I]));
+    E->setArg(I, Reader.ReadExpr());
   E->setTypeBeginLoc(Reader.ReadSourceLocation(Record, Idx));
   E->setTypeAsWritten(Reader.GetType(Record[Idx++]));
   E->setLParenLoc(Reader.ReadSourceLocation(Record, Idx));
   E->setRParenLoc(Reader.ReadSourceLocation(Record, Idx));
-  return E->arg_size();
 }
 
-unsigned PCHStmtReader::VisitOverloadExpr(OverloadExpr *E) {
+void PCHStmtReader::VisitOverloadExpr(OverloadExpr *E) {
   VisitExpr(E);
-  unsigned NumExprs = 0;
   
   unsigned NumTemplateArgs = Record[Idx++];
   assert((NumTemplateArgs != 0) == E->hasExplicitTemplateArgs() &&
          "Read wrong record during creation ?");
-  if (E->hasExplicitTemplateArgs()) {
-    llvm::SmallVectorImpl<Stmt *>::iterator EndOfExprs = StmtStack.end();
-    if (isa<UnresolvedMemberExpr>(E))
-      --EndOfExprs; // UnresolvedMemberExpr contains an Expr.
-    NumExprs = ReadExplicitTemplateArgumentList(E->getExplicitTemplateArgs(),
-                                                NumTemplateArgs, EndOfExprs);
-  }
+  if (E->hasExplicitTemplateArgs())
+    ReadExplicitTemplateArgumentList(E->getExplicitTemplateArgs(),
+                                     NumTemplateArgs);
 
   unsigned NumDecls = Record[Idx++];
   UnresolvedSet<8> Decls;
@@ -1270,40 +1129,63 @@
   E->setQualifier(Reader.ReadNestedNameSpecifier(Record, Idx));
   E->setQualifierRange(Reader.ReadSourceRange(Record, Idx));
   E->setNameLoc(Reader.ReadSourceLocation(Record, Idx));
-  return NumExprs;
 }
 
-unsigned PCHStmtReader::VisitUnresolvedMemberExpr(UnresolvedMemberExpr *E) {
-  unsigned NumExprs = VisitOverloadExpr(E);
+void PCHStmtReader::VisitUnresolvedMemberExpr(UnresolvedMemberExpr *E) {
+  VisitOverloadExpr(E);
   E->setArrow(Record[Idx++]);
   E->setHasUnresolvedUsing(Record[Idx++]);
-  E->setBase(cast_or_null<Expr>(StmtStack.back()));
+  E->setBase(Reader.ReadExpr());
   E->setBaseType(Reader.GetType(Record[Idx++]));
   E->setOperatorLoc(Reader.ReadSourceLocation(Record, Idx));
-  return NumExprs + 1;
 }
 
-unsigned PCHStmtReader::VisitUnresolvedLookupExpr(UnresolvedLookupExpr *E) {
-  unsigned NumExprs = VisitOverloadExpr(E);
+void PCHStmtReader::VisitUnresolvedLookupExpr(UnresolvedLookupExpr *E) {
+  VisitOverloadExpr(E);
   E->setRequiresADL(Record[Idx++]);
   E->setOverloaded(Record[Idx++]);
   E->setNamingClass(cast_or_null<CXXRecordDecl>(Reader.GetDecl(Record[Idx++])));
-  return NumExprs;
 }
 
+Stmt *PCHReader::ReadStmt() {
+  switch (ReadingKind) {
+  case Read_Decl:
+  case Read_Type:
+    // Read a statement from the current DeclCursor.
+    return ReadStmtFromStream(DeclsCursor);
+  case Read_Stmt:
+    // Subexpressions are stored from last to first, so the next Stmt we need
+    // will be at the back of the stack.
+    assert(!StmtStack.empty() && "Read too many sub statements!");
+    return StmtStack.pop_back_val();
+  }
+
+  llvm_unreachable("ReadingKind not set ?");
+  return 0;
+}
+
+Expr *PCHReader::ReadExpr() {
+  return cast_or_null<Expr>(ReadStmt());
+}
 
 // Within the bitstream, expressions are stored in Reverse Polish
 // Notation, with each of the subexpressions preceding the
-// expression they are stored in. To evaluate expressions, we
-// continue reading expressions and placing them on the stack, with
-// expressions having operands removing those operands from the
+// expression they are stored in. Subexpressions are stored from last to first.
+// To evaluate expressions, we continue reading expressions and placing them on
+// the stack, with expressions having operands removing those operands from the
 // stack. Evaluation terminates when we see a STMT_STOP record, and
 // the single remaining expression on the stack is our result.
-Stmt *PCHReader::ReadStmt(llvm::BitstreamCursor &Cursor) {
+Stmt *PCHReader::ReadStmtFromStream(llvm::BitstreamCursor &Cursor) {
+
+  ReadingKindTracker ReadingKind(Read_Stmt, *this);
+  
+#ifndef NDEBUG
+  unsigned PrevNumStmts = StmtStack.size();
+#endif
+
   RecordData Record;
   unsigned Idx;
-  llvm::SmallVector<Stmt *, 16> StmtStack;
-  PCHStmtReader Reader(*this, Record, Idx, StmtStack);
+  PCHStmtReader Reader(*this, Record, Idx);
   Stmt::EmptyShell Empty;
 
   while (true) {
@@ -1709,17 +1591,17 @@
 
     ++NumStatementsRead;
 
-    if (S) {
-      unsigned NumSubStmts = Reader.Visit(S);
-      while (NumSubStmts > 0) {
-        StmtStack.pop_back();
-        --NumSubStmts;
-      }
-    }
+    if (S)
+      Reader.Visit(S);
 
     assert(Idx == Record.size() && "Invalid deserialization of statement");
     StmtStack.push_back(S);
   }
-  assert(StmtStack.size() == 1 && "Extra expressions on stack!");
-  return StmtStack.back();
+
+#ifndef NDEBUG
+  assert(StmtStack.size() > PrevNumStmts && "Read too many sub stmts!");
+  assert(StmtStack.size() == PrevNumStmts + 1 && "Extra expressions on stack!");
+#endif
+
+  return StmtStack.pop_back_val();
 }

Modified: cfe/trunk/lib/Frontend/PCHWriter.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/PCHWriter.cpp?rev=107087&r1=107086&r2=107087&view=diff
==============================================================================
--- cfe/trunk/lib/Frontend/PCHWriter.cpp (original)
+++ cfe/trunk/lib/Frontend/PCHWriter.cpp Mon Jun 28 17:28:35 2010
@@ -2056,8 +2056,8 @@
 
 PCHWriter::PCHWriter(llvm::BitstreamWriter &Stream)
   : Stream(Stream), NextTypeID(pch::NUM_PREDEF_TYPE_IDS),
-    NumStatements(0), NumMacros(0), NumLexicalDeclContexts(0),
-    NumVisibleDeclContexts(0), EmittingStmts(false) { }
+    CollectedStmts(&StmtsToEmit), NumStatements(0), NumMacros(0),
+    NumLexicalDeclContexts(0), NumVisibleDeclContexts(0) { }
 
 void PCHWriter::WritePCH(Sema &SemaRef, MemorizeStatCalls *StatCalls,
                          const char *isysroot) {

Modified: cfe/trunk/lib/Frontend/PCHWriterStmt.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/PCHWriterStmt.cpp?rev=107087&r1=107086&r2=107087&view=diff
==============================================================================
--- cfe/trunk/lib/Frontend/PCHWriterStmt.cpp (original)
+++ cfe/trunk/lib/Frontend/PCHWriterStmt.cpp Mon Jun 28 17:28:35 2010
@@ -147,43 +147,8 @@
   };
 }
 
-/// \brief Return the number of Exprs contained in the given TemplateArgument.
-static unsigned NumExprsContainedIn(const TemplateArgument &Arg) {
-  switch (Arg.getKind()) {
-  default: break;
-  case TemplateArgument::Expression:
-    return 1;
-  case TemplateArgument::Pack: {
-    unsigned Count = 0;
-    for (TemplateArgument::pack_iterator I=Arg.pack_begin(), E=Arg.pack_end();
-           I != E; ++I)
-      Count += NumExprsContainedIn(*I);
-    return Count;
-  }
-  }
-  
-  return 0;
-}
-
-/// \brief Return the number of Exprs contained in the given
-/// ExplicitTemplateArgumentList.
-static unsigned NumExprsContainedIn(const ExplicitTemplateArgumentList &Args) {
-  unsigned Count = 0;
-  for (unsigned i=0; i != Args.NumTemplateArgs; ++i) {
-    const TemplateArgumentLoc &ArgLoc = Args.getTemplateArgs()[i];
-    const TemplateArgument &TemplA = ArgLoc.getArgument();
-    Count += NumExprsContainedIn(TemplA);
-    if (TemplA.getKind() == TemplateArgument::Expression &&
-        TemplA.getAsExpr() != ArgLoc.getLocInfo().getAsExpr())
-      ++Count; // 1 in TemplateArgumentLocInfo.
-  }
-  
-  return Count;
-}
-
 void PCHStmtWriter::
 AddExplicitTemplateArgumentList(const ExplicitTemplateArgumentList &Args) {
-  Record.push_back(NumExprsContainedIn(Args));
   Writer.AddSourceLocation(Args.LAngleLoc, Record);
   Writer.AddSourceLocation(Args.RAngleLoc, Record);
   for (unsigned i=0; i != Args.NumTemplateArgs; ++i)
@@ -204,7 +169,7 @@
   Record.push_back(S->size());
   for (CompoundStmt::body_iterator CS = S->body_begin(), CSEnd = S->body_end();
        CS != CSEnd; ++CS)
-    Writer.WriteSubStmt(*CS);
+    Writer.AddStmt(*CS);
   Writer.AddSourceLocation(S->getLBracLoc(), Record);
   Writer.AddSourceLocation(S->getRBracLoc(), Record);
   Code = pch::STMT_COMPOUND;
@@ -212,14 +177,14 @@
 
 void PCHStmtWriter::VisitSwitchCase(SwitchCase *S) {
   VisitStmt(S);
-  Record.push_back(Writer.RecordSwitchCaseID(S));
+  Record.push_back(Writer.getSwitchCaseID(S));
 }
 
 void PCHStmtWriter::VisitCaseStmt(CaseStmt *S) {
   VisitSwitchCase(S);
-  Writer.WriteSubStmt(S->getLHS());
-  Writer.WriteSubStmt(S->getRHS());
-  Writer.WriteSubStmt(S->getSubStmt());
+  Writer.AddStmt(S->getLHS());
+  Writer.AddStmt(S->getRHS());
+  Writer.AddStmt(S->getSubStmt());
   Writer.AddSourceLocation(S->getCaseLoc(), Record);
   Writer.AddSourceLocation(S->getEllipsisLoc(), Record);
   Writer.AddSourceLocation(S->getColonLoc(), Record);
@@ -228,7 +193,7 @@
 
 void PCHStmtWriter::VisitDefaultStmt(DefaultStmt *S) {
   VisitSwitchCase(S);
-  Writer.WriteSubStmt(S->getSubStmt());
+  Writer.AddStmt(S->getSubStmt());
   Writer.AddSourceLocation(S->getDefaultLoc(), Record);
   Writer.AddSourceLocation(S->getColonLoc(), Record);
   Code = pch::STMT_DEFAULT;
@@ -237,7 +202,7 @@
 void PCHStmtWriter::VisitLabelStmt(LabelStmt *S) {
   VisitStmt(S);
   Writer.AddIdentifierRef(S->getID(), Record);
-  Writer.WriteSubStmt(S->getSubStmt());
+  Writer.AddStmt(S->getSubStmt());
   Writer.AddSourceLocation(S->getIdentLoc(), Record);
   Record.push_back(Writer.GetLabelID(S));
   Code = pch::STMT_LABEL;
@@ -246,9 +211,9 @@
 void PCHStmtWriter::VisitIfStmt(IfStmt *S) {
   VisitStmt(S);
   Writer.AddDeclRef(S->getConditionVariable(), Record);
-  Writer.WriteSubStmt(S->getCond());
-  Writer.WriteSubStmt(S->getThen());
-  Writer.WriteSubStmt(S->getElse());
+  Writer.AddStmt(S->getCond());
+  Writer.AddStmt(S->getThen());
+  Writer.AddStmt(S->getElse());
   Writer.AddSourceLocation(S->getIfLoc(), Record);
   Writer.AddSourceLocation(S->getElseLoc(), Record);
   Code = pch::STMT_IF;
@@ -257,28 +222,28 @@
 void PCHStmtWriter::VisitSwitchStmt(SwitchStmt *S) {
   VisitStmt(S);
   Writer.AddDeclRef(S->getConditionVariable(), Record);
-  Writer.WriteSubStmt(S->getCond());
-  Writer.WriteSubStmt(S->getBody());
+  Writer.AddStmt(S->getCond());
+  Writer.AddStmt(S->getBody());
   Writer.AddSourceLocation(S->getSwitchLoc(), Record);
   for (SwitchCase *SC = S->getSwitchCaseList(); SC;
        SC = SC->getNextSwitchCase())
-    Record.push_back(Writer.getSwitchCaseID(SC));
+    Record.push_back(Writer.RecordSwitchCaseID(SC));
   Code = pch::STMT_SWITCH;
 }
 
 void PCHStmtWriter::VisitWhileStmt(WhileStmt *S) {
   VisitStmt(S);
   Writer.AddDeclRef(S->getConditionVariable(), Record);
-  Writer.WriteSubStmt(S->getCond());
-  Writer.WriteSubStmt(S->getBody());
+  Writer.AddStmt(S->getCond());
+  Writer.AddStmt(S->getBody());
   Writer.AddSourceLocation(S->getWhileLoc(), Record);
   Code = pch::STMT_WHILE;
 }
 
 void PCHStmtWriter::VisitDoStmt(DoStmt *S) {
   VisitStmt(S);
-  Writer.WriteSubStmt(S->getCond());
-  Writer.WriteSubStmt(S->getBody());
+  Writer.AddStmt(S->getCond());
+  Writer.AddStmt(S->getBody());
   Writer.AddSourceLocation(S->getDoLoc(), Record);
   Writer.AddSourceLocation(S->getWhileLoc(), Record);
   Writer.AddSourceLocation(S->getRParenLoc(), Record);
@@ -287,11 +252,11 @@
 
 void PCHStmtWriter::VisitForStmt(ForStmt *S) {
   VisitStmt(S);
-  Writer.WriteSubStmt(S->getInit());
-  Writer.WriteSubStmt(S->getCond());
+  Writer.AddStmt(S->getInit());
+  Writer.AddStmt(S->getCond());
   Writer.AddDeclRef(S->getConditionVariable(), Record);
-  Writer.WriteSubStmt(S->getInc());
-  Writer.WriteSubStmt(S->getBody());
+  Writer.AddStmt(S->getInc());
+  Writer.AddStmt(S->getBody());
   Writer.AddSourceLocation(S->getForLoc(), Record);
   Writer.AddSourceLocation(S->getLParenLoc(), Record);
   Writer.AddSourceLocation(S->getRParenLoc(), Record);
@@ -310,7 +275,7 @@
   VisitStmt(S);
   Writer.AddSourceLocation(S->getGotoLoc(), Record);
   Writer.AddSourceLocation(S->getStarLoc(), Record);
-  Writer.WriteSubStmt(S->getTarget());
+  Writer.AddStmt(S->getTarget());
   Code = pch::STMT_INDIRECT_GOTO;
 }
 
@@ -328,7 +293,7 @@
 
 void PCHStmtWriter::VisitReturnStmt(ReturnStmt *S) {
   VisitStmt(S);
-  Writer.WriteSubStmt(S->getRetValue());
+  Writer.AddStmt(S->getRetValue());
   Writer.AddSourceLocation(S->getReturnLoc(), Record);
   Writer.AddDeclRef(S->getNRVOCandidate(), Record);
   Code = pch::STMT_RETURN;
@@ -354,25 +319,25 @@
   Record.push_back(S->isVolatile());
   Record.push_back(S->isSimple());
   Record.push_back(S->isMSAsm());
-  Writer.WriteSubStmt(S->getAsmString());
+  Writer.AddStmt(S->getAsmString());
 
   // Outputs
   for (unsigned I = 0, N = S->getNumOutputs(); I != N; ++I) {      
     Writer.AddIdentifierRef(S->getOutputIdentifier(I), Record);
-    Writer.WriteSubStmt(S->getOutputConstraintLiteral(I));
-    Writer.WriteSubStmt(S->getOutputExpr(I));
+    Writer.AddStmt(S->getOutputConstraintLiteral(I));
+    Writer.AddStmt(S->getOutputExpr(I));
   }
 
   // Inputs
   for (unsigned I = 0, N = S->getNumInputs(); I != N; ++I) {
     Writer.AddIdentifierRef(S->getInputIdentifier(I), Record);
-    Writer.WriteSubStmt(S->getInputConstraintLiteral(I));
-    Writer.WriteSubStmt(S->getInputExpr(I));
+    Writer.AddStmt(S->getInputConstraintLiteral(I));
+    Writer.AddStmt(S->getInputExpr(I));
   }
 
   // Clobbers
   for (unsigned I = 0, N = S->getNumClobbers(); I != N; ++I)
-    Writer.WriteSubStmt(S->getClobber(I));
+    Writer.AddStmt(S->getClobber(I));
 
   Code = pch::STMT_ASM;
 }
@@ -417,7 +382,7 @@
 
 void PCHStmtWriter::VisitImaginaryLiteral(ImaginaryLiteral *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getSubExpr());
+  Writer.AddStmt(E->getSubExpr());
   Code = pch::EXPR_IMAGINARY_LITERAL;
 }
 
@@ -449,13 +414,13 @@
   VisitExpr(E);
   Writer.AddSourceLocation(E->getLParen(), Record);
   Writer.AddSourceLocation(E->getRParen(), Record);
-  Writer.WriteSubStmt(E->getSubExpr());
+  Writer.AddStmt(E->getSubExpr());
   Code = pch::EXPR_PAREN;
 }
 
 void PCHStmtWriter::VisitUnaryOperator(UnaryOperator *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getSubExpr());
+  Writer.AddStmt(E->getSubExpr());
   Record.push_back(E->getOpcode()); // FIXME: stable encoding
   Writer.AddSourceLocation(E->getOperatorLoc(), Record);
   Code = pch::EXPR_UNARY_OPERATOR;
@@ -493,7 +458,7 @@
     }
   }
   for (unsigned I = 0, N = E->getNumExpressions(); I != N; ++I)
-    Writer.WriteSubStmt(E->getIndexExpr(I));
+    Writer.AddStmt(E->getIndexExpr(I));
   Code = pch::EXPR_OFFSETOF;
 }
 
@@ -504,7 +469,7 @@
     Writer.AddTypeSourceInfo(E->getArgumentTypeInfo(), Record);
   else {
     Record.push_back(0);
-    Writer.WriteSubStmt(E->getArgumentExpr());
+    Writer.AddStmt(E->getArgumentExpr());
   }
   Writer.AddSourceLocation(E->getOperatorLoc(), Record);
   Writer.AddSourceLocation(E->getRParenLoc(), Record);
@@ -513,8 +478,8 @@
 
 void PCHStmtWriter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getLHS());
-  Writer.WriteSubStmt(E->getRHS());
+  Writer.AddStmt(E->getLHS());
+  Writer.AddStmt(E->getRHS());
   Writer.AddSourceLocation(E->getRBracketLoc(), Record);
   Code = pch::EXPR_ARRAY_SUBSCRIPT;
 }
@@ -523,16 +488,16 @@
   VisitExpr(E);
   Record.push_back(E->getNumArgs());
   Writer.AddSourceLocation(E->getRParenLoc(), Record);
-  Writer.WriteSubStmt(E->getCallee());
+  Writer.AddStmt(E->getCallee());
   for (CallExpr::arg_iterator Arg = E->arg_begin(), ArgEnd = E->arg_end();
        Arg != ArgEnd; ++Arg)
-    Writer.WriteSubStmt(*Arg);
+    Writer.AddStmt(*Arg);
   Code = pch::EXPR_CALL;
 }
 
 void PCHStmtWriter::VisitMemberExpr(MemberExpr *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getBase());
+  Writer.AddStmt(E->getBase());
   Writer.AddDeclRef(E->getMemberDecl(), Record);
   Writer.AddSourceLocation(E->getMemberLoc(), Record);
   Record.push_back(E->isArrow());
@@ -543,7 +508,7 @@
 
 void PCHStmtWriter::VisitObjCIsaExpr(ObjCIsaExpr *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getBase());
+  Writer.AddStmt(E->getBase());
   Writer.AddSourceLocation(E->getIsaMemberLoc(), Record);
   Record.push_back(E->isArrow());
   Code = pch::EXPR_OBJC_ISA;
@@ -551,14 +516,14 @@
 
 void PCHStmtWriter::VisitCastExpr(CastExpr *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getSubExpr());
+  Writer.AddStmt(E->getSubExpr());
   Record.push_back(E->getCastKind()); // FIXME: stable encoding
 }
 
 void PCHStmtWriter::VisitBinaryOperator(BinaryOperator *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getLHS());
-  Writer.WriteSubStmt(E->getRHS());
+  Writer.AddStmt(E->getLHS());
+  Writer.AddStmt(E->getRHS());
   Record.push_back(E->getOpcode()); // FIXME: stable encoding
   Writer.AddSourceLocation(E->getOperatorLoc(), Record);
   Code = pch::EXPR_BINARY_OPERATOR;
@@ -573,9 +538,9 @@
 
 void PCHStmtWriter::VisitConditionalOperator(ConditionalOperator *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getCond());
-  Writer.WriteSubStmt(E->getLHS());
-  Writer.WriteSubStmt(E->getRHS());
+  Writer.AddStmt(E->getCond());
+  Writer.AddStmt(E->getLHS());
+  Writer.AddStmt(E->getRHS());
   Writer.AddSourceLocation(E->getQuestionLoc(), Record);
   Writer.AddSourceLocation(E->getColonLoc(), Record);
   Code = pch::EXPR_CONDITIONAL_OPERATOR;
@@ -603,14 +568,14 @@
   VisitExpr(E);
   Writer.AddSourceLocation(E->getLParenLoc(), Record);
   Writer.AddTypeSourceInfo(E->getTypeSourceInfo(), Record);
-  Writer.WriteSubStmt(E->getInitializer());
+  Writer.AddStmt(E->getInitializer());
   Record.push_back(E->isFileScope());
   Code = pch::EXPR_COMPOUND_LITERAL;
 }
 
 void PCHStmtWriter::VisitExtVectorElementExpr(ExtVectorElementExpr *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getBase());
+  Writer.AddStmt(E->getBase());
   Writer.AddIdentifierRef(&E->getAccessor(), Record);
   Writer.AddSourceLocation(E->getAccessorLoc(), Record);
   Code = pch::EXPR_EXT_VECTOR_ELEMENT;
@@ -620,8 +585,8 @@
   VisitExpr(E);
   Record.push_back(E->getNumInits());
   for (unsigned I = 0, N = E->getNumInits(); I != N; ++I)
-    Writer.WriteSubStmt(E->getInit(I));
-  Writer.WriteSubStmt(E->getSyntacticForm());
+    Writer.AddStmt(E->getInit(I));
+  Writer.AddStmt(E->getSyntacticForm());
   Writer.AddSourceLocation(E->getLBraceLoc(), Record);
   Writer.AddSourceLocation(E->getRBraceLoc(), Record);
   Writer.AddDeclRef(E->getInitializedFieldInUnion(), Record);
@@ -633,7 +598,7 @@
   VisitExpr(E);
   Record.push_back(E->getNumSubExprs());
   for (unsigned I = 0, N = E->getNumSubExprs(); I != N; ++I)
-    Writer.WriteSubStmt(E->getSubExpr(I));
+    Writer.AddStmt(E->getSubExpr(I));
   Writer.AddSourceLocation(E->getEqualOrColonLoc(), Record);
   Record.push_back(E->usesGNUSyntax());
   for (DesignatedInitExpr::designators_iterator D = E->designators_begin(),
@@ -673,7 +638,7 @@
 
 void PCHStmtWriter::VisitVAArgExpr(VAArgExpr *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getSubExpr());
+  Writer.AddStmt(E->getSubExpr());
   Writer.AddSourceLocation(E->getBuiltinLoc(), Record);
   Writer.AddSourceLocation(E->getRParenLoc(), Record);
   Code = pch::EXPR_VA_ARG;
@@ -689,7 +654,7 @@
 
 void PCHStmtWriter::VisitStmtExpr(StmtExpr *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getSubStmt());
+  Writer.AddStmt(E->getSubStmt());
   Writer.AddSourceLocation(E->getLParenLoc(), Record);
   Writer.AddSourceLocation(E->getRParenLoc(), Record);
   Code = pch::EXPR_STMT;
@@ -706,9 +671,9 @@
 
 void PCHStmtWriter::VisitChooseExpr(ChooseExpr *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getCond());
-  Writer.WriteSubStmt(E->getLHS());
-  Writer.WriteSubStmt(E->getRHS());
+  Writer.AddStmt(E->getCond());
+  Writer.AddStmt(E->getLHS());
+  Writer.AddStmt(E->getRHS());
   Writer.AddSourceLocation(E->getBuiltinLoc(), Record);
   Writer.AddSourceLocation(E->getRParenLoc(), Record);
   Code = pch::EXPR_CHOOSE;
@@ -724,7 +689,7 @@
   VisitExpr(E);
   Record.push_back(E->getNumSubExprs());
   for (unsigned I = 0, N = E->getNumSubExprs(); I != N; ++I)
-    Writer.WriteSubStmt(E->getExpr(I));
+    Writer.AddStmt(E->getExpr(I));
   Writer.AddSourceLocation(E->getBuiltinLoc(), Record);
   Writer.AddSourceLocation(E->getRParenLoc(), Record);
   Code = pch::EXPR_SHUFFLE_VECTOR;
@@ -743,7 +708,7 @@
   Writer.AddSourceLocation(E->getLocation(), Record);
   Record.push_back(E->isByRef());
   Record.push_back(E->isConstQualAdded());
-  Writer.WriteSubStmt(E->getCopyConstructorExpr());
+  Writer.AddStmt(E->getCopyConstructorExpr());
   Code = pch::EXPR_BLOCK_DECL_REF;
 }
 
@@ -753,7 +718,7 @@
 
 void PCHStmtWriter::VisitObjCStringLiteral(ObjCStringLiteral *E) {
   VisitExpr(E);
-  Writer.WriteSubStmt(E->getString());
+  Writer.AddStmt(E->getString());
   Writer.AddSourceLocation(E->getAtLoc(), Record);
   Code = pch::EXPR_OBJC_STRING_LITERAL;
 }
@@ -786,7 +751,7 @@
   VisitExpr(E);
   Writer.AddDeclRef(E->getDecl(), Record);
   Writer.AddSourceLocation(E->getLocation(), Record);
-  Writer.WriteSubStmt(E->getBase());
+  Writer.AddStmt(E->getBase());
   Record.push_back(E->isArrow());
   Record.push_back(E->isFreeIvar());
   Code = pch::EXPR_OBJC_IVAR_REF_EXPR;
@@ -796,7 +761,7 @@
   VisitExpr(E);
   Writer.AddDeclRef(E->getProperty(), Record);
   Writer.AddSourceLocation(E->getLocation(), Record);
-  Writer.WriteSubStmt(E->getBase());
+  Writer.AddStmt(E->getBase());
   Code = pch::EXPR_OBJC_PROPERTY_REF_EXPR;
 }
 
@@ -808,7 +773,7 @@
 
   // NOTE: InterfaceDecl and Base are mutually exclusive.
   Writer.AddDeclRef(E->getInterfaceDecl(), Record);
-  Writer.WriteSubStmt(E->getBase());
+  Writer.AddStmt(E->getBase());
   Writer.AddSourceLocation(E->getLocation(), Record);
   Writer.AddSourceLocation(E->getClassLoc(), Record);
   Code = pch::EXPR_OBJC_KVC_REF_EXPR;
@@ -820,7 +785,7 @@
   Record.push_back((unsigned)E->getReceiverKind()); // FIXME: stable encoding
   switch (E->getReceiverKind()) {
   case ObjCMessageExpr::Instance:
-    Writer.WriteSubStmt(E->getInstanceReceiver());
+    Writer.AddStmt(E->getInstanceReceiver());
     break;
 
   case ObjCMessageExpr::Class:
@@ -847,7 +812,7 @@
 
   for (CallExpr::arg_iterator Arg = E->arg_begin(), ArgEnd = E->arg_end();
        Arg != ArgEnd; ++Arg)
-    Writer.WriteSubStmt(*Arg);
+    Writer.AddStmt(*Arg);
   Code = pch::EXPR_OBJC_MESSAGE_EXPR;
 }
 
@@ -859,16 +824,16 @@
 
 void PCHStmtWriter::VisitObjCForCollectionStmt(ObjCForCollectionStmt *S) {
   VisitStmt(S);
-  Writer.WriteSubStmt(S->getElement());
-  Writer.WriteSubStmt(S->getCollection());
-  Writer.WriteSubStmt(S->getBody());
+  Writer.AddStmt(S->getElement());
+  Writer.AddStmt(S->getCollection());
+  Writer.AddStmt(S->getBody());
   Writer.AddSourceLocation(S->getForLoc(), Record);
   Writer.AddSourceLocation(S->getRParenLoc(), Record);
   Code = pch::STMT_OBJC_FOR_COLLECTION;
 }
 
 void PCHStmtWriter::VisitObjCAtCatchStmt(ObjCAtCatchStmt *S) {
-  Writer.WriteSubStmt(S->getCatchBody());
+  Writer.AddStmt(S->getCatchBody());
   Writer.AddDeclRef(S->getCatchParamDecl(), Record);
   Writer.AddSourceLocation(S->getAtCatchLoc(), Record);
   Writer.AddSourceLocation(S->getRParenLoc(), Record);
@@ -876,7 +841,7 @@
 }
 
 void PCHStmtWriter::VisitObjCAtFinallyStmt(ObjCAtFinallyStmt *S) {
-  Writer.WriteSubStmt(S->getFinallyBody());
+  Writer.AddStmt(S->getFinallyBody());
   Writer.AddSourceLocation(S->getAtFinallyLoc(), Record);
   Code = pch::STMT_OBJC_FINALLY;
 }
@@ -884,24 +849,24 @@
 void PCHStmtWriter::VisitObjCAtTryStmt(ObjCAtTryStmt *S) {
   Record.push_back(S->getNumCatchStmts());
   Record.push_back(S->getFinallyStmt() != 0);
-  Writer.WriteSubStmt(S->getTryBody());
+  Writer.AddStmt(S->getTryBody());
   for (unsigned I = 0, N = S->getNumCatchStmts(); I != N; ++I)
-    Writer.WriteSubStmt(S->getCatchStmt(I));
+    Writer.AddStmt(S->getCatchStmt(I));
   if (S->getFinallyStmt())
-    Writer.WriteSubStmt(S->getFinallyStmt());
+    Writer.AddStmt(S->getFinallyStmt());
   Writer.AddSourceLocation(S->getAtTryLoc(), Record);
   Code = pch::STMT_OBJC_AT_TRY;
 }
 
 void PCHStmtWriter::VisitObjCAtSynchronizedStmt(ObjCAtSynchronizedStmt *S) {
-  Writer.WriteSubStmt(S->getSynchExpr());
-  Writer.WriteSubStmt(S->getSynchBody());
+  Writer.AddStmt(S->getSynchExpr());
+  Writer.AddStmt(S->getSynchBody());
   Writer.AddSourceLocation(S->getAtSynchronizedLoc(), Record);
   Code = pch::STMT_OBJC_AT_SYNCHRONIZED;
 }
 
 void PCHStmtWriter::VisitObjCAtThrowStmt(ObjCAtThrowStmt *S) {
-  Writer.WriteSubStmt(S->getThrowExpr());
+  Writer.AddStmt(S->getThrowExpr());
   Writer.AddSourceLocation(S->getThrowLoc(), Record);
   Code = pch::STMT_OBJC_AT_THROW;
 }
@@ -925,7 +890,7 @@
   VisitExpr(E);
   Record.push_back(E->getNumArgs());
   for (unsigned I = 0, N = E->getNumArgs(); I != N; ++I)
-    Writer.WriteSubStmt(E->getArg(I));
+    Writer.AddStmt(E->getArg(I));
   Writer.AddDeclRef(E->getConstructor(), Record);
   Writer.AddSourceLocation(E->getLocation(), Record);
   Record.push_back(E->isElidable());
@@ -986,7 +951,7 @@
     Writer.AddTypeSourceInfo(E->getTypeOperandSourceInfo(), Record);
     Code = pch::EXPR_CXX_TYPEID_TYPE;
   } else {
-    Writer.WriteSubStmt(E->getExprOperand());
+    Writer.AddStmt(E->getExprOperand());
     Code = pch::EXPR_CXX_TYPEID_EXPR;
   }
 }
@@ -1001,7 +966,7 @@
 void PCHStmtWriter::VisitCXXThrowExpr(CXXThrowExpr *E) {
   VisitExpr(E);
   Writer.AddSourceLocation(E->getThrowLoc(), Record);
-  Writer.WriteSubStmt(E->getSubExpr());
+  Writer.AddStmt(E->getSubExpr());
   Code = pch::EXPR_CXX_THROW;
 }
 
@@ -1010,7 +975,7 @@
   Writer.AddSourceLocation(E->getUsedLocation(), Record);
   if (E->isExprStored()) {
     Record.push_back(1);
-    Writer.WriteSubStmt(E->getExpr());
+    Writer.AddStmt(E->getExpr());
   } else {
     Record.push_back(0);
   }
@@ -1021,7 +986,7 @@
 void PCHStmtWriter::VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) {
   VisitExpr(E);
   Writer.AddCXXTemporary(E->getTemporary(), Record);
-  Writer.WriteSubStmt(E->getSubExpr());
+  Writer.AddStmt(E->getSubExpr());
   Code = pch::EXPR_CXX_BIND_TEMPORARY;
 }
 
@@ -1047,7 +1012,7 @@
   Writer.AddSourceLocation(E->getEndLoc(), Record);
   for (CXXNewExpr::arg_iterator I = E->raw_arg_begin(), e = E->raw_arg_end();
        I != e; ++I)
-    Writer.WriteSubStmt(*I);
+    Writer.AddStmt(*I);
   
   Code = pch::EXPR_CXX_NEW;
 }
@@ -1057,7 +1022,7 @@
   Record.push_back(E->isGlobalDelete());
   Record.push_back(E->isArrayForm());
   Writer.AddDeclRef(E->getOperatorDelete(), Record);
-  Writer.WriteSubStmt(E->getArgument());
+  Writer.AddStmt(E->getArgument());
   Writer.AddSourceLocation(E->getSourceRange().getBegin(), Record);
   
   Code = pch::EXPR_CXX_DELETE;
@@ -1091,7 +1056,7 @@
   for (unsigned i = 0, e = E->getNumTemporaries(); i != e; ++i)
     Writer.AddCXXTemporary(E->getTemporary(i), Record);
   
-  Writer.WriteSubStmt(E->getSubExpr());
+  Writer.AddStmt(E->getSubExpr());
   Code = pch::EXPR_CXX_EXPR_WITH_TEMPORARIES;
 }
 
@@ -1113,9 +1078,9 @@
   }
   
   if (!E->isImplicitAccess())
-    Writer.WriteSubStmt(E->getBase());
+    Writer.AddStmt(E->getBase());
   else
-    Writer.WriteSubStmt(0);
+    Writer.AddStmt(0);
   Writer.AddTypeRef(E->getBaseType(), Record);
   Record.push_back(E->isArrow());
   Writer.AddSourceLocation(E->getOperatorLoc(), Record);
@@ -1156,7 +1121,7 @@
   Record.push_back(E->arg_size());
   for (CXXUnresolvedConstructExpr::arg_iterator
          ArgI = E->arg_begin(), ArgE = E->arg_end(); ArgI != ArgE; ++ArgI)
-    Writer.WriteSubStmt(*ArgI);
+    Writer.AddStmt(*ArgI);
   Writer.AddSourceLocation(E->getTypeBeginLoc(), Record);
   Writer.AddTypeRef(E->getTypeAsWritten(), Record);
   Writer.AddSourceLocation(E->getLParenLoc(), Record);
@@ -1196,7 +1161,7 @@
   VisitOverloadExpr(E);
   Record.push_back(E->isArrow());
   Record.push_back(E->hasUnresolvedUsing());
-  Writer.WriteSubStmt(!E->isImplicitAccess() ? E->getBase() : 0);
+  Writer.AddStmt(!E->isImplicitAccess() ? E->getBase() : 0);
   Writer.AddTypeRef(E->getBaseType(), Record);
   Writer.AddSourceLocation(E->getOperatorLoc(), Record);
   Code = pch::EXPR_CXX_UNRESOLVED_MEMBER;
@@ -1246,12 +1211,16 @@
   RecordData Record;
   PCHStmtWriter Writer(*this, Record);
   ++NumStatements;
-
+  
   if (!S) {
     Stream.EmitRecord(pch::STMT_NULL_PTR, Record);
     return;
   }
 
+  // Redirect PCHWriter::AddStmt to collect sub stmts.
+  llvm::SmallVector<Stmt *, 16> SubStmts;
+  CollectedStmts = &SubStmts;
+
   Writer.Code = pch::STMT_NULL_PTR;
   Writer.Visit(S);
   
@@ -1263,6 +1232,17 @@
     assert(0 && "Unhandled sub statement writing PCH file");
   }
 #endif
+
+  // Revert PCHWriter::AddStmt.
+  CollectedStmts = &StmtsToEmit;
+
+  // Write the sub stmts in reverse order, last to first. When reading them back
+  // we will read them in correct order by "pop"ing them from the Stmts stack.
+  // This simplifies reading and allows to store a variable number of sub stmts
+  // without knowing it in advance.
+  while (!SubStmts.empty())
+    WriteSubStmt(SubStmts.pop_back_val());
+  
   Stream.EmitRecord(Writer.Code, Record);
 }
 
@@ -1270,41 +1250,18 @@
 /// queue via AddStmt().
 void PCHWriter::FlushStmts() {
   RecordData Record;
-  PCHStmtWriter Writer(*this, Record);
-  
-  EmittingStmts = true;
 
   for (unsigned I = 0, N = StmtsToEmit.size(); I != N; ++I) {
-    ++NumStatements;
-    Stmt *S = StmtsToEmit[I];
-
-    if (!S) {
-      Stream.EmitRecord(pch::STMT_NULL_PTR, Record);
-      Stream.EmitRecord(pch::STMT_STOP, Record);
-      continue;
-    }
-
-    Writer.Code = pch::STMT_NULL_PTR;
-    Writer.Visit(S);
-#ifndef NDEBUG
-    if (Writer.Code == pch::STMT_NULL_PTR) {
-      S->dump();
-      assert(0 && "Unhandled expression writing PCH file");
-    }
-#endif
-    Stream.EmitRecord(Writer.Code, Record);
-
+    WriteSubStmt(StmtsToEmit[I]);
+    
     assert(N == StmtsToEmit.size() &&
            "Substatement writen via AddStmt rather than WriteSubStmt!");
 
     // Note that we are at the end of a full expression. Any
     // expression records that follow this one are part of a different
     // expression.
-    Record.clear();
     Stream.EmitRecord(pch::STMT_STOP, Record);
   }
 
-  EmittingStmts = false;
-
   StmtsToEmit.clear();
 }

Modified: cfe/trunk/test/PCH/exprs.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/PCH/exprs.c?rev=107087&r1=107086&r2=107087&view=diff
==============================================================================
--- cfe/trunk/test/PCH/exprs.c (original)
+++ cfe/trunk/test/PCH/exprs.c Mon Jun 28 17:28:35 2010
@@ -59,6 +59,8 @@
 // CompoundAssignOperator
 addeq_result *int_ptr6 = &integer;
 
+add_result_with_typeinfo *int_typeinfo_ptr6;
+
 // ConditionalOperator
 conditional_operator *double_ptr4 = &floating;
 

Modified: cfe/trunk/test/PCH/exprs.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/PCH/exprs.h?rev=107087&r1=107086&r2=107087&view=diff
==============================================================================
--- cfe/trunk/test/PCH/exprs.h (original)
+++ cfe/trunk/test/PCH/exprs.h Mon Jun 28 17:28:35 2010
@@ -72,6 +72,8 @@
 // CompoundLiteral
 typedef typeof((struct S){.x = 3.5}) compound_literal;
 
+typedef typeof(i + sizeof(int[i + Enumerator])) add_result_with_typeinfo;
+
 // ExtVectorElementExpr
 typedef __attribute__(( ext_vector_type(2) )) double double2;
 extern double2 vec2, vec2b;





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