Move VTT builder to AST

llvm-svn: 140501

clang/include/clang/AST/VTTBuilder.h

+//===--- VTTBuilder.h - C++ VTT layout builder --------------------*- C++ -*-=//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This contains code dealing with generation of the layout of virtual table
+// tables (VTT).
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_AST_VTTBUILDER_H
+#define LLVM_CLANG_AST_VTTBUILDER_H
+
+#include "clang/AST/BaseSubobject.h"
+#include "clang/AST/CXXInheritance.h"
+#include "clang/AST/GlobalDecl.h"
+#include "clang/AST/RecordLayout.h"
+#include "clang/Basic/ABI.h"
+#include "llvm/ADT/SetVector.h"
+#include <utility>
+
+namespace clang {
+
+class VTTVTable {
+  llvm::PointerIntPair<const CXXRecordDecl *, 1, bool> BaseAndIsVirtual;
+  CharUnits BaseOffset;
+
+public:
+  VTTVTable() {}
+  VTTVTable(const CXXRecordDecl *Base, CharUnits BaseOffset, bool BaseIsVirtual)
+    : BaseAndIsVirtual(Base, BaseIsVirtual), BaseOffset(BaseOffset) {}
+  VTTVTable(BaseSubobject Base, bool BaseIsVirtual)
+    : BaseAndIsVirtual(Base.getBase(), BaseIsVirtual),
+      BaseOffset(Base.getBaseOffset()) {}
+
+  const CXXRecordDecl *getBase() const {
+    return BaseAndIsVirtual.getPointer();
+  }
+
+  CharUnits getBaseOffset() const {
+    return BaseOffset;
+  }
+
+  bool isVirtual() const {
+    return BaseAndIsVirtual.getInt();
+  }
+
+  BaseSubobject getBaseSubobject() const {
+    return BaseSubobject(getBase(), getBaseOffset());
+  }
+};
+
+struct VTTComponent {
+  uint64_t VTableIndex;
+  BaseSubobject VTableBase;
+
+  VTTComponent() {}
+  VTTComponent(uint64_t VTableIndex, BaseSubobject VTableBase)
+    : VTableIndex(VTableIndex), VTableBase(VTableBase) {}
+};
+
+/// VTT builder - Class for building VTT layout information.
+class VTTBuilder {
+  
+  ASTContext &Ctx;
+
+  /// MostDerivedClass - The most derived class for which we're building this
+  /// vtable.
+  const CXXRecordDecl *MostDerivedClass;
+
+  typedef SmallVector<VTTVTable, 64> VTTVTablesVectorTy;
+  
+  /// VTTVTables - The VTT vtables.
+  VTTVTablesVectorTy VTTVTables;
+  
+  typedef SmallVector<VTTComponent, 64> VTTComponentsVectorTy;
+  
+  /// VTTComponents - The VTT components.
+  VTTComponentsVectorTy VTTComponents;
+  
+  /// MostDerivedClassLayout - the AST record layout of the most derived class.
+  const ASTRecordLayout &MostDerivedClassLayout;
+
+  typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBasesSetTy;
+
+  typedef llvm::DenseMap<BaseSubobject, uint64_t> AddressPointsMapTy;
+
+  /// SubVTTIndicies - The sub-VTT indices for the bases of the most derived
+  /// class.
+  llvm::DenseMap<BaseSubobject, uint64_t> SubVTTIndicies;
+
+  /// SecondaryVirtualPointerIndices - The secondary virtual pointer indices of
+  /// all subobjects of the most derived class.
+  llvm::DenseMap<BaseSubobject, uint64_t> SecondaryVirtualPointerIndices;
+
+  /// GenerateDefinition - Whether the VTT builder should generate LLVM IR for
+  /// the VTT.
+  bool GenerateDefinition;
+
+  /// AddVTablePointer - Add a vtable pointer to the VTT currently being built.
+  ///
+  /// \param AddressPoints - If the vtable is a construction vtable, this has
+  /// the address points for it.
+  void AddVTablePointer(BaseSubobject Base, uint64_t VTableIndex,
+                        const CXXRecordDecl *VTableClass);
+                        
+  /// LayoutSecondaryVTTs - Lay out the secondary VTTs of the given base 
+  /// subobject.
+  void LayoutSecondaryVTTs(BaseSubobject Base);
+  
+  /// LayoutSecondaryVirtualPointers - Lay out the secondary virtual pointers
+  /// for the given base subobject.
+  ///
+  /// \param BaseIsMorallyVirtual whether the base subobject is a virtual base
+  /// or a direct or indirect base of a virtual base.
+  ///
+  /// \param AddressPoints - If the vtable is a construction vtable, this has
+  /// the address points for it.
+  void LayoutSecondaryVirtualPointers(BaseSubobject Base, 
+                                      bool BaseIsMorallyVirtual,
+                                      uint64_t VTableIndex,
+                                      const CXXRecordDecl *VTableClass,
+                                      VisitedVirtualBasesSetTy &VBases);
+  
+  /// LayoutSecondaryVirtualPointers - Lay out the secondary virtual pointers
+  /// for the given base subobject.
+  ///
+  /// \param AddressPoints - If the vtable is a construction vtable, this has
+  /// the address points for it.
+  void LayoutSecondaryVirtualPointers(BaseSubobject Base, 
+                                      uint64_t VTableIndex);
+
+  /// LayoutVirtualVTTs - Lay out the VTTs for the virtual base classes of the
+  /// given record decl.
+  void LayoutVirtualVTTs(const CXXRecordDecl *RD,
+                         VisitedVirtualBasesSetTy &VBases);
+  
+  /// LayoutVTT - Will lay out the VTT for the given subobject, including any
+  /// secondary VTTs, secondary virtual pointers and virtual VTTs.
+  void LayoutVTT(BaseSubobject Base, bool BaseIsVirtual);
+  
+public:
+  VTTBuilder(ASTContext &Ctx, const CXXRecordDecl *MostDerivedClass,
+             bool GenerateDefinition);
+
+  // getVTTComponents - Returns a reference to the VTT components.
+  const VTTComponentsVectorTy &getVTTComponents() const {
+    return VTTComponents;
+  }
+  
+  // getVTTVTables - Returns a reference to the VTT vtables.
+  const VTTVTablesVectorTy &getVTTVTables() const {
+    return VTTVTables;
+  }
+  
+  /// getSubVTTIndicies - Returns a reference to the sub-VTT indices.
+  const llvm::DenseMap<BaseSubobject, uint64_t> &getSubVTTIndicies() const {
+    return SubVTTIndicies;
+  }
+  
+  /// getSecondaryVirtualPointerIndices - Returns a reference to the secondary
+  /// virtual pointer indices.
+  const llvm::DenseMap<BaseSubobject, uint64_t> &
+  getSecondaryVirtualPointerIndices() const {
+    return SecondaryVirtualPointerIndices;
+  }
+
+};
+
+}
+
+#endif

clang/lib/AST/CMakeLists.txt

@@ -46,6 +46,7 @@ add_clang_library(clangAST
   Type.cpp
   TypeLoc.cpp
   TypePrinter.cpp
+  VTTBuilder.cpp
   )
 
 add_dependencies(clangAST ClangARMNeon ClangAttrClasses ClangAttrList 

clang/lib/AST/VTTBuilder.cpp

+//===--- VTTBuilder.cpp - C++ VTT layout builder --------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This contains code dealing with generation of the layout of virtual table
+// tables (VTT).
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/VTTBuilder.h"
+#include "clang/AST/CXXInheritance.h"
+#include "clang/AST/RecordLayout.h"
+#include "clang/Basic/TargetInfo.h"
+#include "llvm/Support/Format.h"
+#include <algorithm>
+#include <cstdio>
+
+using namespace clang;
+
+#define DUMP_OVERRIDERS 0
+
+VTTBuilder::VTTBuilder(ASTContext &Ctx,
+                       const CXXRecordDecl *MostDerivedClass,
+                       bool GenerateDefinition)
+  : Ctx(Ctx), MostDerivedClass(MostDerivedClass), 
+  MostDerivedClassLayout(Ctx.getASTRecordLayout(MostDerivedClass)),
+    GenerateDefinition(GenerateDefinition) {
+  // Lay out this VTT.
+  LayoutVTT(BaseSubobject(MostDerivedClass, CharUnits::Zero()), 
+            /*BaseIsVirtual=*/false);
+}
+
+void VTTBuilder::AddVTablePointer(BaseSubobject Base, uint64_t VTableIndex,
+                                  const CXXRecordDecl *VTableClass) {
+  // Store the vtable pointer index if we're generating the primary VTT.
+  if (VTableClass == MostDerivedClass) {
+    assert(!SecondaryVirtualPointerIndices.count(Base) &&
+           "A virtual pointer index already exists for this base subobject!");
+    SecondaryVirtualPointerIndices[Base] = VTTComponents.size();
+  }
+
+  if (!GenerateDefinition) {
+    VTTComponents.push_back(VTTComponent());
+    return;
+  }
+
+  VTTComponents.push_back(VTTComponent(VTableIndex, Base));
+}
+
+void VTTBuilder::LayoutSecondaryVTTs(BaseSubobject Base) {
+  const CXXRecordDecl *RD = Base.getBase();
+
+  for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
+       E = RD->bases_end(); I != E; ++I) {
+    
+    // Don't layout virtual bases.
+    if (I->isVirtual())
+        continue;
+
+    const CXXRecordDecl *BaseDecl =
+      cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
+
+    const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD);
+    CharUnits BaseOffset = Base.getBaseOffset() + 
+      Layout.getBaseClassOffset(BaseDecl);
+   
+    // Layout the VTT for this base.
+    LayoutVTT(BaseSubobject(BaseDecl, BaseOffset), /*BaseIsVirtual=*/false);
+  }
+}
+
+void
+VTTBuilder::LayoutSecondaryVirtualPointers(BaseSubobject Base, 
+                                           bool BaseIsMorallyVirtual,
+                                           uint64_t VTableIndex,
+                                           const CXXRecordDecl *VTableClass,
+                                           VisitedVirtualBasesSetTy &VBases) {
+  const CXXRecordDecl *RD = Base.getBase();
+  
+  // We're not interested in bases that don't have virtual bases, and not
+  // morally virtual bases.
+  if (!RD->getNumVBases() && !BaseIsMorallyVirtual)
+    return;
+
+  for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
+       E = RD->bases_end(); I != E; ++I) {
+    const CXXRecordDecl *BaseDecl =
+      cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
+
+    // Itanium C++ ABI 2.6.2:
+    //   Secondary virtual pointers are present for all bases with either
+    //   virtual bases or virtual function declarations overridden along a 
+    //   virtual path.
+    //
+    // If the base class is not dynamic, we don't want to add it, nor any
+    // of its base classes.
+    if (!BaseDecl->isDynamicClass())
+      continue;
+    
+    bool BaseDeclIsMorallyVirtual = BaseIsMorallyVirtual;
+    bool BaseDeclIsNonVirtualPrimaryBase = false;
+    CharUnits BaseOffset;
+    if (I->isVirtual()) {
+      // Ignore virtual bases that we've already visited.
+      if (!VBases.insert(BaseDecl))
+        continue;
+      
+      BaseOffset = MostDerivedClassLayout.getVBaseClassOffset(BaseDecl);
+      BaseDeclIsMorallyVirtual = true;
+    } else {
+      const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD);
+      
+      BaseOffset = Base.getBaseOffset() + 
+        Layout.getBaseClassOffset(BaseDecl);
+      
+      if (!Layout.isPrimaryBaseVirtual() &&
+          Layout.getPrimaryBase() == BaseDecl)
+        BaseDeclIsNonVirtualPrimaryBase = true;
+    }
+
+    // Itanium C++ ABI 2.6.2:
+    //   Secondary virtual pointers: for each base class X which (a) has virtual
+    //   bases or is reachable along a virtual path from D, and (b) is not a
+    //   non-virtual primary base, the address of the virtual table for X-in-D
+    //   or an appropriate construction virtual table.
+    if (!BaseDeclIsNonVirtualPrimaryBase &&
+        (BaseDecl->getNumVBases() || BaseDeclIsMorallyVirtual)) {
+      // Add the vtable pointer.
+      AddVTablePointer(BaseSubobject(BaseDecl, BaseOffset), VTableIndex, 
+                       VTableClass);
+    }
+
+    // And lay out the secondary virtual pointers for the base class.
+    LayoutSecondaryVirtualPointers(BaseSubobject(BaseDecl, BaseOffset),
+                                   BaseDeclIsMorallyVirtual, VTableIndex, 
+                                   VTableClass, VBases);
+  }
+}
+
+void 
+VTTBuilder::LayoutSecondaryVirtualPointers(BaseSubobject Base, 
+                                           uint64_t VTableIndex) {
+  VisitedVirtualBasesSetTy VBases;
+  LayoutSecondaryVirtualPointers(Base, /*BaseIsMorallyVirtual=*/false,
+                                 VTableIndex, Base.getBase(), VBases);
+}
+
+void VTTBuilder::LayoutVirtualVTTs(const CXXRecordDecl *RD,
+                                   VisitedVirtualBasesSetTy &VBases) {
+  for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
+       E = RD->bases_end(); I != E; ++I) {
+    const CXXRecordDecl *BaseDecl = 
+      cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
+    
+    // Check if this is a virtual base.
+    if (I->isVirtual()) {
+      // Check if we've seen this base before.
+      if (!VBases.insert(BaseDecl))
+        continue;
+    
+      CharUnits BaseOffset = 
+        MostDerivedClassLayout.getVBaseClassOffset(BaseDecl);
+      
+      LayoutVTT(BaseSubobject(BaseDecl, BaseOffset), /*BaseIsVirtual=*/true);
+    }
+    
+    // We only need to layout virtual VTTs for this base if it actually has
+    // virtual bases.
+    if (BaseDecl->getNumVBases())
+      LayoutVirtualVTTs(BaseDecl, VBases);
+  }
+}
+
+void VTTBuilder::LayoutVTT(BaseSubobject Base, bool BaseIsVirtual) {
+  const CXXRecordDecl *RD = Base.getBase();
+
+  // Itanium C++ ABI 2.6.2:
+  //   An array of virtual table addresses, called the VTT, is declared for 
+  //   each class type that has indirect or direct virtual base classes.
+  if (RD->getNumVBases() == 0)
+    return;
+
+  bool IsPrimaryVTT = Base.getBase() == MostDerivedClass;
+
+  if (!IsPrimaryVTT) {
+    // Remember the sub-VTT index.
+    SubVTTIndicies[Base] = VTTComponents.size();
+  }
+
+  uint64_t VTableIndex = VTTVTables.size();
+  VTTVTables.push_back(VTTVTable(Base, BaseIsVirtual));
+
+  // Add the primary vtable pointer.
+  AddVTablePointer(Base, VTableIndex, RD);
+
+  // Add the secondary VTTs.
+  LayoutSecondaryVTTs(Base);
+  
+  // Add the secondary virtual pointers.
+  LayoutSecondaryVirtualPointers(Base, VTableIndex);
+  
+  // If this is the primary VTT, we want to lay out virtual VTTs as well.
+  if (IsPrimaryVTT) {
+    VisitedVirtualBasesSetTy VBases;
+    LayoutVirtualVTTs(Base.getBase(), VBases);
+  }
+}

clang/lib/CodeGen/CGVTT.cpp

@@ -14,170 +14,12 @@
 #include "CodeGenModule.h"
 #include "CGCXXABI.h"
 #include "clang/AST/RecordLayout.h"
+#include "clang/AST/VTTBuilder.h"
 using namespace clang;
 using namespace CodeGen;
 
 #define D1(x)
 
-namespace {
-
-class VTTVTable {
-  llvm::PointerIntPair<const CXXRecordDecl *, 1, bool> BaseAndIsVirtual;
-  CharUnits BaseOffset;
-
-public:
-  VTTVTable() {}
-  VTTVTable(const CXXRecordDecl *Base, CharUnits BaseOffset, bool BaseIsVirtual)
-    : BaseAndIsVirtual(Base, BaseIsVirtual), BaseOffset(BaseOffset) {}
-  VTTVTable(BaseSubobject Base, bool BaseIsVirtual)
-    : BaseAndIsVirtual(Base.getBase(), BaseIsVirtual),
-      BaseOffset(Base.getBaseOffset()) {}
-
-  const CXXRecordDecl *getBase() const {
-    return BaseAndIsVirtual.getPointer();
-  }
-
-  CharUnits getBaseOffset() const {
-    return BaseOffset;
-  }
-
-  bool isVirtual() const {
-    return BaseAndIsVirtual.getInt();
-  }
-
-  BaseSubobject getBaseSubobject() const {
-    return BaseSubobject(getBase(), getBaseOffset());
-  }
-};
-
-struct VTTComponent {
-  uint64_t VTableIndex;
-  BaseSubobject VTableBase;
-
-  VTTComponent() {}
-  VTTComponent(uint64_t VTableIndex, BaseSubobject VTableBase)
-    : VTableIndex(VTableIndex), VTableBase(VTableBase) {}
-};
-
-/// VTT builder - Class for building VTT layout information.
-class VTTBuilder {
-  
-  ASTContext &Ctx;
-
-  /// MostDerivedClass - The most derived class for which we're building this
-  /// vtable.
-  const CXXRecordDecl *MostDerivedClass;
-
-  typedef SmallVector<VTTVTable, 64> VTTVTablesVectorTy;
-  
-  /// VTTVTables - The VTT vtables.
-  VTTVTablesVectorTy VTTVTables;
-  
-  typedef SmallVector<VTTComponent, 64> VTTComponentsVectorTy;
-  
-  /// VTTComponents - The VTT components.
-  VTTComponentsVectorTy VTTComponents;
-  
-  /// MostDerivedClassLayout - the AST record layout of the most derived class.
-  const ASTRecordLayout &MostDerivedClassLayout;
-
-  typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBasesSetTy;
-
-  typedef llvm::DenseMap<BaseSubobject, uint64_t> AddressPointsMapTy;
-
-  /// SubVTTIndicies - The sub-VTT indices for the bases of the most derived
-  /// class.
-  llvm::DenseMap<BaseSubobject, uint64_t> SubVTTIndicies;
-
-  /// SecondaryVirtualPointerIndices - The secondary virtual pointer indices of
-  /// all subobjects of the most derived class.
-  llvm::DenseMap<BaseSubobject, uint64_t> SecondaryVirtualPointerIndices;
-
-  /// GenerateDefinition - Whether the VTT builder should generate LLVM IR for
-  /// the VTT.
-  bool GenerateDefinition;
-
-  /// AddVTablePointer - Add a vtable pointer to the VTT currently being built.
-  ///
-  /// \param AddressPoints - If the vtable is a construction vtable, this has
-  /// the address points for it.
-  void AddVTablePointer(BaseSubobject Base, uint64_t VTableIndex,
-                        const CXXRecordDecl *VTableClass);
-                        
-  /// LayoutSecondaryVTTs - Lay out the secondary VTTs of the given base 
-  /// subobject.
-  void LayoutSecondaryVTTs(BaseSubobject Base);
-  
-  /// LayoutSecondaryVirtualPointers - Lay out the secondary virtual pointers
-  /// for the given base subobject.
-  ///
-  /// \param BaseIsMorallyVirtual whether the base subobject is a virtual base
-  /// or a direct or indirect base of a virtual base.
-  ///
-  /// \param AddressPoints - If the vtable is a construction vtable, this has
-  /// the address points for it.
-  void LayoutSecondaryVirtualPointers(BaseSubobject Base, 
-                                      bool BaseIsMorallyVirtual,
-                                      uint64_t VTableIndex,
-                                      const CXXRecordDecl *VTableClass,
-                                      VisitedVirtualBasesSetTy &VBases);
-  
-  /// LayoutSecondaryVirtualPointers - Lay out the secondary virtual pointers
-  /// for the given base subobject.
-  ///
-  /// \param AddressPoints - If the vtable is a construction vtable, this has
-  /// the address points for it.
-  void LayoutSecondaryVirtualPointers(BaseSubobject Base, 
-                                      uint64_t VTableIndex);
-
-  /// LayoutVirtualVTTs - Lay out the VTTs for the virtual base classes of the
-  /// given record decl.
-  void LayoutVirtualVTTs(const CXXRecordDecl *RD,
-                         VisitedVirtualBasesSetTy &VBases);
-  
-  /// LayoutVTT - Will lay out the VTT for the given subobject, including any
-  /// secondary VTTs, secondary virtual pointers and virtual VTTs.
-  void LayoutVTT(BaseSubobject Base, bool BaseIsVirtual);
-  
-public:
-  VTTBuilder(ASTContext &Ctx, const CXXRecordDecl *MostDerivedClass,
-             bool GenerateDefinition);
-
-  // getVTTComponents - Returns a reference to the VTT components.
-  const VTTComponentsVectorTy &getVTTComponents() const {
-    return VTTComponents;
-  }
-  
-  // getVTTVTables - Returns a reference to the VTT vtables.
-  const VTTVTablesVectorTy &getVTTVTables() const {
-    return VTTVTables;
-  }
-  
-  /// getSubVTTIndicies - Returns a reference to the sub-VTT indices.
-  const llvm::DenseMap<BaseSubobject, uint64_t> &getSubVTTIndicies() const {
-    return SubVTTIndicies;
-  }
-  
-  /// getSecondaryVirtualPointerIndices - Returns a reference to the secondary
-  /// virtual pointer indices.
-  const llvm::DenseMap<BaseSubobject, uint64_t> &
-  getSecondaryVirtualPointerIndices() const {
-    return SecondaryVirtualPointerIndices;
-  }
-
-};
-
-VTTBuilder::VTTBuilder(ASTContext &Ctx,
-                       const CXXRecordDecl *MostDerivedClass,
-                       bool GenerateDefinition)
-  : Ctx(Ctx), MostDerivedClass(MostDerivedClass), 
-  MostDerivedClassLayout(Ctx.getASTRecordLayout(MostDerivedClass)),
-    GenerateDefinition(GenerateDefinition) {
-  // Lay out this VTT.
-  LayoutVTT(BaseSubobject(MostDerivedClass, CharUnits::Zero()), 
-            /*BaseIsVirtual=*/false);
-}
-
 llvm::Constant *GetAddrOfVTTVTable(CodeGenVTables &CGVT,
                                    const CXXRecordDecl *MostDerivedClass,
                                    const VTTVTable &VTable,
@@ -197,184 +39,6 @@ llvm::Constant *GetAddrOfVTTVTable(CodeGenVTables &CGVT,
                                          AddressPoints);
 }
 
-void VTTBuilder::AddVTablePointer(BaseSubobject Base, uint64_t VTableIndex,
-                                  const CXXRecordDecl *VTableClass) {
-  // Store the vtable pointer index if we're generating the primary VTT.
-  if (VTableClass == MostDerivedClass) {
-    assert(!SecondaryVirtualPointerIndices.count(Base) &&
-           "A virtual pointer index already exists for this base subobject!");
-    SecondaryVirtualPointerIndices[Base] = VTTComponents.size();
-  }
-
-  if (!GenerateDefinition) {
-    VTTComponents.push_back(VTTComponent());
-    return;
-  }
-
-  VTTComponents.push_back(VTTComponent(VTableIndex, Base));
-}
-
-void VTTBuilder::LayoutSecondaryVTTs(BaseSubobject Base) {
-  const CXXRecordDecl *RD = Base.getBase();
-
-  for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
-       E = RD->bases_end(); I != E; ++I) {
-    
-    // Don't layout virtual bases.
-    if (I->isVirtual())
-        continue;
-
-    const CXXRecordDecl *BaseDecl =
-      cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
-
-    const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD);
-    CharUnits BaseOffset = Base.getBaseOffset() + 
-      Layout.getBaseClassOffset(BaseDecl);
-   
-    // Layout the VTT for this base.
-    LayoutVTT(BaseSubobject(BaseDecl, BaseOffset), /*BaseIsVirtual=*/false);
-  }
-}
-
-void
-VTTBuilder::LayoutSecondaryVirtualPointers(BaseSubobject Base, 
-                                           bool BaseIsMorallyVirtual,
-                                           uint64_t VTableIndex,
-                                           const CXXRecordDecl *VTableClass,
-                                           VisitedVirtualBasesSetTy &VBases) {
-  const CXXRecordDecl *RD = Base.getBase();
-  
-  // We're not interested in bases that don't have virtual bases, and not
-  // morally virtual bases.
-  if (!RD->getNumVBases() && !BaseIsMorallyVirtual)
-    return;
-
-  for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
-       E = RD->bases_end(); I != E; ++I) {
-    const CXXRecordDecl *BaseDecl =
-      cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
-
-    // Itanium C++ ABI 2.6.2:
-    //   Secondary virtual pointers are present for all bases with either
-    //   virtual bases or virtual function declarations overridden along a 
-    //   virtual path.
-    //
-    // If the base class is not dynamic, we don't want to add it, nor any
-    // of its base classes.
-    if (!BaseDecl->isDynamicClass())
-      continue;
-    
-    bool BaseDeclIsMorallyVirtual = BaseIsMorallyVirtual;
-    bool BaseDeclIsNonVirtualPrimaryBase = false;
-    CharUnits BaseOffset;
-    if (I->isVirtual()) {
-      // Ignore virtual bases that we've already visited.
-      if (!VBases.insert(BaseDecl))
-        continue;
-      
-      BaseOffset = MostDerivedClassLayout.getVBaseClassOffset(BaseDecl);
-      BaseDeclIsMorallyVirtual = true;
-    } else {
-      const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD);
-      
-      BaseOffset = Base.getBaseOffset() + 
-        Layout.getBaseClassOffset(BaseDecl);
-      
-      if (!Layout.isPrimaryBaseVirtual() &&
-          Layout.getPrimaryBase() == BaseDecl)
-        BaseDeclIsNonVirtualPrimaryBase = true;
-    }
-
-    // Itanium C++ ABI 2.6.2:
-    //   Secondary virtual pointers: for each base class X which (a) has virtual
-    //   bases or is reachable along a virtual path from D, and (b) is not a
-    //   non-virtual primary base, the address of the virtual table for X-in-D
-    //   or an appropriate construction virtual table.
-    if (!BaseDeclIsNonVirtualPrimaryBase &&
-        (BaseDecl->getNumVBases() || BaseDeclIsMorallyVirtual)) {
-      // Add the vtable pointer.
-      AddVTablePointer(BaseSubobject(BaseDecl, BaseOffset), VTableIndex, 
-                       VTableClass);
-    }
-
-    // And lay out the secondary virtual pointers for the base class.
-    LayoutSecondaryVirtualPointers(BaseSubobject(BaseDecl, BaseOffset),
-                                   BaseDeclIsMorallyVirtual, VTableIndex, 
-                                   VTableClass, VBases);
-  }
-}
-
-void 
-VTTBuilder::LayoutSecondaryVirtualPointers(BaseSubobject Base, 
-                                           uint64_t VTableIndex) {
-  VisitedVirtualBasesSetTy VBases;
-  LayoutSecondaryVirtualPointers(Base, /*BaseIsMorallyVirtual=*/false,
-                                 VTableIndex, Base.getBase(), VBases);
-}
-
-void VTTBuilder::LayoutVirtualVTTs(const CXXRecordDecl *RD,
-                                   VisitedVirtualBasesSetTy &VBases) {
-  for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
-       E = RD->bases_end(); I != E; ++I) {
-    const CXXRecordDecl *BaseDecl = 
-      cast<CXXRecordDecl>(I->getType()->getAs<RecordType>()->getDecl());
-    
-    // Check if this is a virtual base.
-    if (I->isVirtual()) {
-      // Check if we've seen this base before.
-      if (!VBases.insert(BaseDecl))
-        continue;
-    
-      CharUnits BaseOffset = 
-        MostDerivedClassLayout.getVBaseClassOffset(BaseDecl);
-      
-      LayoutVTT(BaseSubobject(BaseDecl, BaseOffset), /*BaseIsVirtual=*/true);
-    }
-    
-    // We only need to layout virtual VTTs for this base if it actually has
-    // virtual bases.
-    if (BaseDecl->getNumVBases())
-      LayoutVirtualVTTs(BaseDecl, VBases);
-  }
-}
-
-void VTTBuilder::LayoutVTT(BaseSubobject Base, bool BaseIsVirtual) {
-  const CXXRecordDecl *RD = Base.getBase();
-
-  // Itanium C++ ABI 2.6.2:
-  //   An array of virtual table addresses, called the VTT, is declared for 
-  //   each class type that has indirect or direct virtual base classes.
-  if (RD->getNumVBases() == 0)
-    return;
-
-  bool IsPrimaryVTT = Base.getBase() == MostDerivedClass;
-
-  if (!IsPrimaryVTT) {
-    // Remember the sub-VTT index.
-    SubVTTIndicies[Base] = VTTComponents.size();
-  }
-
-  uint64_t VTableIndex = VTTVTables.size();
-  VTTVTables.push_back(VTTVTable(Base, BaseIsVirtual));
-
-  // Add the primary vtable pointer.
-  AddVTablePointer(Base, VTableIndex, RD);
-
-  // Add the secondary VTTs.
-  LayoutSecondaryVTTs(Base);
-  
-  // Add the secondary virtual pointers.
-  LayoutSecondaryVirtualPointers(Base, VTableIndex);
-  
-  // If this is the primary VTT, we want to lay out virtual VTTs as well.
-  if (IsPrimaryVTT) {
-    VisitedVirtualBasesSetTy VBases;
-    LayoutVirtualVTTs(Base.getBase(), VBases);
-  }
-}
-  
-}
-
 void
 CodeGenVTables::EmitVTTDefinition(llvm::GlobalVariable *VTT,
                                   llvm::GlobalVariable::LinkageTypes Linkage,