Move the VTT related code into its own file, CGVTT.cpp

llvm-svn: 94079

4 files changed, 403 insertions, 378 deletions

diff --git a/clang/clang.xcodeproj/project.pbxproj b/clang/clang.xcodeproj/project.pbxproj
index 72d0b45931d..d1cd032ec03 100644
--- a/clang/clang.xcodeproj/project.pbxproj
+++ b/clang/clang.xcodeproj/project.pbxproj
@@ -43,6 +43,7 @@
 		1A81AA19108144F40094E50B /* CGVtable.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 1A81AA18108144F40094E50B /* CGVtable.cpp */; };
 		1A869A700BA2164C008DA07A /* LiteralSupport.h in CopyFiles */ = {isa = PBXBuildFile; fileRef = 1A869A6E0BA2164C008DA07A /* LiteralSupport.h */; };
 		1A869AA80BA21ABA008DA07A /* LiteralSupport.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 1A869AA70BA21ABA008DA07A /* LiteralSupport.cpp */; };
+		1A97825B1108BA18002B98FC /* CGVTT.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 1A97825A1108BA18002B98FC /* CGVTT.cpp */; };
 		1A986AB710D0746D00A8EA9E /* CGDeclCXX.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 1A986AB610D0746D00A8EA9E /* CGDeclCXX.cpp */; };
 		1AA1D91810125DE30078DEBC /* RecordLayoutBuilder.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 1AA1D91610125DE30078DEBC /* RecordLayoutBuilder.cpp */; };
 		1AA963C410D85A7300786C86 /* FullExpr.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 1AA963C310D85A7300786C86 /* FullExpr.cpp */; };
@@ -404,6 +405,7 @@
 		1A81AA5D108278A20094E50B /* CGVtable.h */ = {isa = PBXFileReference; fileEncoding = 4; indentWidth = 2; lastKnownFileType = sourcecode.c.h; name = CGVtable.h; path = lib/CodeGen/CGVtable.h; sourceTree = "<group>"; tabWidth = 2; };
 		1A869A6E0BA2164C008DA07A /* LiteralSupport.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = LiteralSupport.h; sourceTree = "<group>"; };
 		1A869AA70BA21ABA008DA07A /* LiteralSupport.cpp */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.cpp.cpp; path = LiteralSupport.cpp; sourceTree = "<group>"; };
+		1A97825A1108BA18002B98FC /* CGVTT.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = CGVTT.cpp; path = lib/CodeGen/CGVTT.cpp; sourceTree = "<group>"; };
 		1A986AB610D0746D00A8EA9E /* CGDeclCXX.cpp */ = {isa = PBXFileReference; fileEncoding = 4; indentWidth = 2; lastKnownFileType = sourcecode.cpp.cpp; name = CGDeclCXX.cpp; path = lib/CodeGen/CGDeclCXX.cpp; sourceTree = "<group>"; tabWidth = 2; };
 		1AA1D91610125DE30078DEBC /* RecordLayoutBuilder.cpp */ = {isa = PBXFileReference; fileEncoding = 4; indentWidth = 2; lastKnownFileType = sourcecode.cpp.cpp; name = RecordLayoutBuilder.cpp; path = lib/AST/RecordLayoutBuilder.cpp; sourceTree = "<group>"; tabWidth = 2; };
 		1AA1D91710125DE30078DEBC /* RecordLayoutBuilder.h */ = {isa = PBXFileReference; fileEncoding = 4; indentWidth = 2; lastKnownFileType = sourcecode.c.h; name = RecordLayoutBuilder.h; path = lib/AST/RecordLayoutBuilder.h; sourceTree = "<group>"; tabWidth = 2; };
@@ -1317,6 +1319,7 @@
 				35475B230E7997680000BFE4 /* CGValue.h */,
 				1A81AA18108144F40094E50B /* CGVtable.cpp */,
 				1A81AA5D108278A20094E50B /* CGVtable.h */,
+				1A97825A1108BA18002B98FC /* CGVTT.cpp */,
 				DE928B800C0A615B00231DA4 /* CodeGenFunction.h */,
 				DE928B820C0A616000231DA4 /* CodeGenFunction.cpp */,
 				DE928B7C0C0A615100231DA4 /* CodeGenModule.h */,
@@ -1963,6 +1966,7 @@
 				1ACB57EA1105820D0047B991 /* LangStandards.cpp in Sources */,
 				1ACB57EB1105820D0047B991 /* TypeXML.cpp in Sources */,
 				1ACB57EC1105820D0047B991 /* VerifyDiagnosticsClient.cpp in Sources */,
+				1A97825B1108BA18002B98FC /* CGVTT.cpp in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
diff --git a/clang/lib/CodeGen/CGVTT.cpp b/clang/lib/CodeGen/CGVTT.cpp
new file mode 100644
index 00000000000..9714bd9d967
--- /dev/null
+++ b/clang/lib/CodeGen/CGVTT.cpp
@@ -0,0 +1,398 @@
+//===--- CGVTT.cpp - Emit LLVM Code for C++ VTTs --------------------------===//
+//
+//                     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 C++ code generation of VTTs (vtable tables).
+//
+//===----------------------------------------------------------------------===//
+
+#include "CodeGenModule.h"
+#include "clang/AST/RecordLayout.h"
+using namespace clang;
+using namespace CodeGen;
+
+#define D1(x)
+
+namespace {
+class VTTBuilder {
+  /// Inits - The list of values built for the VTT.
+  std::vector<llvm::Constant *> &Inits;
+  /// Class - The most derived class that this vtable is being built for.
+  const CXXRecordDecl *Class;
+  CodeGenModule &CGM;  // Per-module state.
+  llvm::SmallSet<const CXXRecordDecl *, 32> SeenVBase;
+  /// BLayout - Layout for the most derived class that this vtable is being
+  /// built for.
+  const ASTRecordLayout &BLayout;
+  CGVtableInfo::AddrMap_t &AddressPoints;
+  // vtbl - A pointer to the vtable for Class.
+  llvm::Constant *ClassVtbl;
+  llvm::LLVMContext &VMContext;
+
+  /// SeenVBasesInSecondary - The seen virtual bases when building the 
+  /// secondary virtual pointers.
+  llvm::SmallPtrSet<const CXXRecordDecl *, 32> SeenVBasesInSecondary;
+
+  llvm::DenseMap<const CXXRecordDecl *, uint64_t> SubVTTIndicies;
+  
+  bool GenerateDefinition;
+
+  llvm::DenseMap<BaseSubobject, llvm::Constant *> CtorVtables;
+  llvm::DenseMap<std::pair<const CXXRecordDecl *, BaseSubobject>, uint64_t> 
+    CtorVtableAddressPoints;
+  
+  llvm::Constant *getCtorVtable(const BaseSubobject &Base) {
+    if (!GenerateDefinition)
+      return 0;
+
+    llvm::Constant *&CtorVtable = CtorVtables[Base];
+    if (!CtorVtable) {
+      // Build the vtable.
+      CGVtableInfo::CtorVtableInfo Info
+        = CGM.getVtableInfo().getCtorVtable(Class, Base);
+      
+      CtorVtable = Info.Vtable;
+      
+      // Add the address points for this base.
+      for (CGVtableInfo::AddressPointsMapTy::const_iterator I =
+           Info.AddressPoints.begin(), E = Info.AddressPoints.end(); 
+           I != E; ++I) {
+        uint64_t &AddressPoint = 
+          CtorVtableAddressPoints[std::make_pair(Base.getBase(), I->first)];
+        
+        // Check if we already have the address points for this base.
+        if (AddressPoint)
+          break;
+
+        // Otherwise, insert it.
+        AddressPoint = I->second;
+      }      
+    }
+    
+    return CtorVtable;
+  }
+  
+  
+  /// BuildVtablePtr - Build up a referene to the given secondary vtable
+  llvm::Constant *BuildVtablePtr(llvm::Constant *Vtable,
+                                 const CXXRecordDecl *VtableClass,
+                                 const CXXRecordDecl *RD,
+                                 uint64_t Offset) {
+    if (!GenerateDefinition)
+      return 0;
+
+    uint64_t AddressPoint;
+    
+    if (VtableClass != Class) {
+      // We have a ctor vtable, look for the address point in the ctor vtable
+      // address points.
+      AddressPoint = 
+        CtorVtableAddressPoints[std::make_pair(VtableClass, 
+                                               BaseSubobject(RD, Offset))];
+    } else { 
+      AddressPoint = 
+        (*AddressPoints[VtableClass])[std::make_pair(RD, Offset)];
+    }
+
+    // FIXME: We can never have 0 address point.  Do this for now so gepping
+    // retains the same structure.  Later we'll just assert.
+    if (AddressPoint == 0)
+      AddressPoint = 1;
+    D1(printf("XXX address point for %s in %s layout %s at offset %d was %d\n",
+              RD->getNameAsCString(), VtblClass->getNameAsCString(),
+              Class->getNameAsCString(), (int)Offset, (int)AddressPoint));
+
+    llvm::Value *Idxs[] = {
+      llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), 0),
+      llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), AddressPoint)
+    };
+    
+    llvm::Constant *Init = 
+      llvm::ConstantExpr::getInBoundsGetElementPtr(Vtable, Idxs, 2);
+
+    const llvm::Type *Int8PtrTy = llvm::Type::getInt8PtrTy(VMContext);
+    return llvm::ConstantExpr::getBitCast(Init, Int8PtrTy);
+  }
+
+  /// Secondary - Add the secondary vtable pointers to Inits.  Offset is the
+  /// current offset in bits to the object we're working on.
+  void Secondary(const CXXRecordDecl *RD, llvm::Constant *vtbl,
+                 const CXXRecordDecl *VtblClass, uint64_t Offset=0,
+                 bool MorallyVirtual=false) {
+    if (RD->getNumVBases() == 0 && ! MorallyVirtual)
+      return;
+
+    for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
+           e = RD->bases_end(); i != e; ++i) {
+      const CXXRecordDecl *Base =
+        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
+
+      // We only want to visit each virtual base once.
+      if (i->isVirtual() && SeenVBasesInSecondary.count(Base))
+        continue;
+      
+      // 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 (!Base->isDynamicClass())
+        continue;
+
+      const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
+      const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
+      const bool PrimaryBaseWasVirtual = Layout.getPrimaryBaseWasVirtual();
+      bool NonVirtualPrimaryBase;
+      NonVirtualPrimaryBase = !PrimaryBaseWasVirtual && Base == PrimaryBase;
+      bool BaseMorallyVirtual = MorallyVirtual | i->isVirtual();
+      uint64_t BaseOffset;
+      if (!i->isVirtual()) {
+        const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
+        BaseOffset = Offset + Layout.getBaseClassOffset(Base);
+      } else
+        BaseOffset = BLayout.getVBaseClassOffset(Base);
+      llvm::Constant *subvtbl = vtbl;
+      const CXXRecordDecl *subVtblClass = VtblClass;
+      if ((Base->getNumVBases() || BaseMorallyVirtual)
+          && !NonVirtualPrimaryBase) {
+        llvm::Constant *init;
+        if (BaseMorallyVirtual || VtblClass == Class)
+          init = BuildVtablePtr(vtbl, VtblClass, Base, BaseOffset);
+        else {
+          init = getCtorVtable(BaseSubobject(Base, BaseOffset));
+          
+          subvtbl = init;
+          subVtblClass = Base;
+          
+          init = BuildVtablePtr(init, Class, Base, BaseOffset);
+        }
+
+        Inits.push_back(init);
+      }
+      
+      if (i->isVirtual())
+        SeenVBasesInSecondary.insert(Base);
+      
+      Secondary(Base, subvtbl, subVtblClass, BaseOffset, BaseMorallyVirtual);
+    }
+  }
+
+  /// BuiltVTT - Add the VTT to Inits.  Offset is the offset in bits to the
+  /// currnet object we're working on.
+  void BuildVTT(const CXXRecordDecl *RD, uint64_t Offset, bool MorallyVirtual) {
+    // 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;
+
+    // Remember the sub-VTT index.
+    SubVTTIndicies[RD] = Inits.size();
+
+    llvm::Constant *Vtable;
+    const CXXRecordDecl *VtableClass;
+
+    // First comes the primary virtual table pointer...
+    if (MorallyVirtual) {
+      Vtable = ClassVtbl;
+      VtableClass = Class;
+    } else {
+      Vtable = getCtorVtable(BaseSubobject(RD, Offset));
+      VtableClass = RD;
+    }
+    
+    llvm::Constant *Init = BuildVtablePtr(Vtable, VtableClass, RD, Offset);
+    Inits.push_back(Init);
+
+    // then the secondary VTTs....
+    SecondaryVTTs(RD, Offset, MorallyVirtual);
+
+    // Make sure to clear the set of seen virtual bases.
+    SeenVBasesInSecondary.clear();
+
+    // and last the secondary vtable pointers.
+    Secondary(RD, Vtable, VtableClass, Offset, MorallyVirtual);
+  }
+
+  /// SecondaryVTTs - Add the secondary VTTs to Inits.  The secondary VTTs are
+  /// built from each direct non-virtual proper base that requires a VTT in
+  /// declaration order.
+  void SecondaryVTTs(const CXXRecordDecl *RD, uint64_t Offset=0,
+                     bool MorallyVirtual=false) {
+    for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
+           e = RD->bases_end(); i != e; ++i) {
+      const CXXRecordDecl *Base =
+        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
+      if (i->isVirtual())
+        continue;
+      const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
+      uint64_t BaseOffset = Offset + Layout.getBaseClassOffset(Base);
+      
+      BuildVTT(Base, BaseOffset, MorallyVirtual);
+    }
+  }
+
+  /// VirtualVTTs - Add the VTT for each proper virtual base in inheritance
+  /// graph preorder.
+  void VirtualVTTs(const CXXRecordDecl *RD) {
+    for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
+           e = RD->bases_end(); i != e; ++i) {
+      const CXXRecordDecl *Base =
+        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
+      if (i->isVirtual() && !SeenVBase.count(Base)) {
+        SeenVBase.insert(Base);
+        uint64_t BaseOffset = BLayout.getVBaseClassOffset(Base);
+        BuildVTT(Base, BaseOffset, false);
+      }
+      VirtualVTTs(Base);
+    }
+  }
+
+public:
+  VTTBuilder(std::vector<llvm::Constant *> &inits, const CXXRecordDecl *c,
+             CodeGenModule &cgm, bool GenerateDefinition)
+    : Inits(inits), Class(c), CGM(cgm),
+      BLayout(cgm.getContext().getASTRecordLayout(c)),
+      AddressPoints(*cgm.getVtableInfo().AddressPoints[c]),
+      VMContext(cgm.getModule().getContext()),
+      GenerateDefinition(GenerateDefinition) {
+    
+    // First comes the primary virtual table pointer for the complete class...
+    ClassVtbl = GenerateDefinition ? CGM.getVtableInfo().getVtable(Class) : 0;
+
+    llvm::Constant *Init = BuildVtablePtr(ClassVtbl, Class, Class, 0);
+    Inits.push_back(Init);
+    
+    // then the secondary VTTs...
+    SecondaryVTTs(Class);
+
+    // Make sure to clear the set of seen virtual bases.
+    SeenVBasesInSecondary.clear();
+
+    // then the secondary vtable pointers...
+    Secondary(Class, ClassVtbl, Class);
+
+    // and last, the virtual VTTs.
+    VirtualVTTs(Class);
+  }
+  
+  llvm::DenseMap<const CXXRecordDecl *, uint64_t> &getSubVTTIndicies() {
+    return SubVTTIndicies;
+  }
+};
+}
+
+llvm::GlobalVariable *
+CGVtableInfo::GenerateVTT(llvm::GlobalVariable::LinkageTypes Linkage,
+                          bool GenerateDefinition,
+                          const CXXRecordDecl *RD) {
+  // Only classes that have virtual bases need a VTT.
+  if (RD->getNumVBases() == 0)
+    return 0;
+
+  llvm::SmallString<256> OutName;
+  CGM.getMangleContext().mangleCXXVTT(RD, OutName);
+  llvm::StringRef Name = OutName.str();
+
+  D1(printf("vtt %s\n", RD->getNameAsCString()));
+
+  llvm::GlobalVariable *GV = CGM.getModule().getGlobalVariable(Name);
+  if (GV == 0 || GV->isDeclaration()) {
+    const llvm::Type *Int8PtrTy = 
+      llvm::Type::getInt8PtrTy(CGM.getLLVMContext());
+
+    std::vector<llvm::Constant *> inits;
+    VTTBuilder b(inits, RD, CGM, GenerateDefinition);
+
+    const llvm::ArrayType *Type = llvm::ArrayType::get(Int8PtrTy, inits.size());
+    llvm::Constant *Init = 0;
+    if (GenerateDefinition)
+      Init = llvm::ConstantArray::get(Type, inits);
+
+    llvm::GlobalVariable *OldGV = GV;
+    GV = new llvm::GlobalVariable(CGM.getModule(), Type, /*isConstant=*/true, 
+                                  Linkage, Init, Name);
+    CGM.setGlobalVisibility(GV, RD);
+    
+    if (OldGV) {
+      GV->takeName(OldGV);
+      llvm::Constant *NewPtr = 
+        llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
+      OldGV->replaceAllUsesWith(NewPtr);
+      OldGV->eraseFromParent();
+    }
+  }
+  
+  return GV;
+}
+
+CGVtableInfo::CtorVtableInfo 
+CGVtableInfo::getCtorVtable(const CXXRecordDecl *RD, 
+                            const BaseSubobject &Base) {
+  CtorVtableInfo Info;
+  
+  Info.Vtable = GenerateVtable(llvm::GlobalValue::InternalLinkage,
+                               /*GenerateDefinition=*/true,
+                               RD, Base.getBase(), Base.getBaseOffset(),
+                               Info.AddressPoints);
+  return Info;
+}
+
+llvm::GlobalVariable *CGVtableInfo::getVTT(const CXXRecordDecl *RD) {
+  return GenerateVTT(llvm::GlobalValue::ExternalLinkage, 
+                     /*GenerateDefinition=*/false, RD);
+  
+}
+
+
+bool CGVtableInfo::needsVTTParameter(GlobalDecl GD) {
+  const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
+  
+  // We don't have any virtual bases, just return early.
+  if (!MD->getParent()->getNumVBases())
+    return false;
+  
+  // Check if we have a base constructor.
+  if (isa<CXXConstructorDecl>(MD) && GD.getCtorType() == Ctor_Base)
+    return true;
+
+  // Check if we have a base destructor.
+  if (isa<CXXDestructorDecl>(MD) && GD.getDtorType() == Dtor_Base)
+    return true;
+  
+  return false;
+}
+
+uint64_t CGVtableInfo::getSubVTTIndex(const CXXRecordDecl *RD, 
+                                      const CXXRecordDecl *Base) {
+  ClassPairTy ClassPair(RD, Base);
+
+  SubVTTIndiciesTy::iterator I = 
+    SubVTTIndicies.find(ClassPair);
+  if (I != SubVTTIndicies.end())
+    return I->second;
+  
+  std::vector<llvm::Constant *> inits;
+  VTTBuilder Builder(inits, RD, CGM, /*GenerateDefinition=*/false);
+
+  for (llvm::DenseMap<const CXXRecordDecl *, uint64_t>::iterator I =
+       Builder.getSubVTTIndicies().begin(), 
+       E = Builder.getSubVTTIndicies().end(); I != E; ++I) {
+    // Insert all indices.
+    ClassPairTy ClassPair(RD, I->first);
+    
+    SubVTTIndicies.insert(std::make_pair(ClassPair, I->second));
+  }
+    
+  I = SubVTTIndicies.find(ClassPair);
+  assert(I != SubVTTIndicies.end() && "Did not find index!");
+  
+  return I->second;
+}
diff --git a/clang/lib/CodeGen/CGVtable.cpp b/clang/lib/CodeGen/CGVtable.cpp
index b2fb8662fe6..1da10010f5d 100644
--- a/clang/lib/CodeGen/CGVtable.cpp
+++ b/clang/lib/CodeGen/CGVtable.cpp
@@ -1205,321 +1205,6 @@ CGVtableInfo::GenerateVtable(llvm::GlobalVariable::LinkageTypes Linkage,
   return GV;
 }
 
-namespace {
-class VTTBuilder {
-  /// Inits - The list of values built for the VTT.
-  std::vector<llvm::Constant *> &Inits;
-  /// Class - The most derived class that this vtable is being built for.
-  const CXXRecordDecl *Class;
-  CodeGenModule &CGM;  // Per-module state.
-  llvm::SmallSet<const CXXRecordDecl *, 32> SeenVBase;
-  /// BLayout - Layout for the most derived class that this vtable is being
-  /// built for.
-  const ASTRecordLayout &BLayout;
-  CGVtableInfo::AddrMap_t &AddressPoints;
-  // vtbl - A pointer to the vtable for Class.
-  llvm::Constant *ClassVtbl;
-  llvm::LLVMContext &VMContext;
-
-  /// SeenVBasesInSecondary - The seen virtual bases when building the 
-  /// secondary virtual pointers.
-  llvm::SmallPtrSet<const CXXRecordDecl *, 32> SeenVBasesInSecondary;
-
-  llvm::DenseMap<const CXXRecordDecl *, uint64_t> SubVTTIndicies;
-  
-  bool GenerateDefinition;
-
-  llvm::DenseMap<BaseSubobject, llvm::Constant *> CtorVtables;
-  llvm::DenseMap<std::pair<const CXXRecordDecl *, BaseSubobject>, uint64_t> 
-    CtorVtableAddressPoints;
-  
-  llvm::Constant *getCtorVtable(const BaseSubobject &Base) {
-    if (!GenerateDefinition)
-      return 0;
-
-    llvm::Constant *&CtorVtable = CtorVtables[Base];
-    if (!CtorVtable) {
-      // Build the vtable.
-      CGVtableInfo::CtorVtableInfo Info
-        = CGM.getVtableInfo().getCtorVtable(Class, Base);
-      
-      CtorVtable = Info.Vtable;
-      
-      // Add the address points for this base.
-      for (CGVtableInfo::AddressPointsMapTy::const_iterator I =
-           Info.AddressPoints.begin(), E = Info.AddressPoints.end(); 
-           I != E; ++I) {
-        uint64_t &AddressPoint = 
-          CtorVtableAddressPoints[std::make_pair(Base.getBase(), I->first)];
-        
-        // Check if we already have the address points for this base.
-        if (AddressPoint)
-          break;
-
-        // Otherwise, insert it.
-        AddressPoint = I->second;
-      }      
-    }
-    
-    return CtorVtable;
-  }
-  
-  
-  /// BuildVtablePtr - Build up a referene to the given secondary vtable
-  llvm::Constant *BuildVtablePtr(llvm::Constant *Vtable,
-                                 const CXXRecordDecl *VtableClass,
-                                 const CXXRecordDecl *RD,
-                                 uint64_t Offset) {
-    if (!GenerateDefinition)
-      return 0;
-
-    uint64_t AddressPoint;
-    
-    if (VtableClass != Class) {
-      // We have a ctor vtable, look for the address point in the ctor vtable
-      // address points.
-      AddressPoint = 
-        CtorVtableAddressPoints[std::make_pair(VtableClass, 
-                                               BaseSubobject(RD, Offset))];
-    } else { 
-      AddressPoint = 
-        (*AddressPoints[VtableClass])[std::make_pair(RD, Offset)];
-    }
-
-    // FIXME: We can never have 0 address point.  Do this for now so gepping
-    // retains the same structure.  Later we'll just assert.
-    if (AddressPoint == 0)
-      AddressPoint = 1;
-    D1(printf("XXX address point for %s in %s layout %s at offset %d was %d\n",
-              RD->getNameAsCString(), VtblClass->getNameAsCString(),
-              Class->getNameAsCString(), (int)Offset, (int)AddressPoint));
-
-    llvm::Value *Idxs[] = {
-      llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), 0),
-      llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext), AddressPoint)
-    };
-    
-    llvm::Constant *Init = 
-      llvm::ConstantExpr::getInBoundsGetElementPtr(Vtable, Idxs, 2);
-
-    const llvm::Type *Int8PtrTy = llvm::Type::getInt8PtrTy(VMContext);
-    return llvm::ConstantExpr::getBitCast(Init, Int8PtrTy);
-  }
-
-  /// Secondary - Add the secondary vtable pointers to Inits.  Offset is the
-  /// current offset in bits to the object we're working on.
-  void Secondary(const CXXRecordDecl *RD, llvm::Constant *vtbl,
-                 const CXXRecordDecl *VtblClass, uint64_t Offset=0,
-                 bool MorallyVirtual=false) {
-    if (RD->getNumVBases() == 0 && ! MorallyVirtual)
-      return;
-
-    for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
-           e = RD->bases_end(); i != e; ++i) {
-      const CXXRecordDecl *Base =
-        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
-
-      // We only want to visit each virtual base once.
-      if (i->isVirtual() && SeenVBasesInSecondary.count(Base))
-        continue;
-      
-      // 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 (!Base->isDynamicClass())
-        continue;
-
-      const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
-      const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
-      const bool PrimaryBaseWasVirtual = Layout.getPrimaryBaseWasVirtual();
-      bool NonVirtualPrimaryBase;
-      NonVirtualPrimaryBase = !PrimaryBaseWasVirtual && Base == PrimaryBase;
-      bool BaseMorallyVirtual = MorallyVirtual | i->isVirtual();
-      uint64_t BaseOffset;
-      if (!i->isVirtual()) {
-        const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
-        BaseOffset = Offset + Layout.getBaseClassOffset(Base);
-      } else
-        BaseOffset = BLayout.getVBaseClassOffset(Base);
-      llvm::Constant *subvtbl = vtbl;
-      const CXXRecordDecl *subVtblClass = VtblClass;
-      if ((Base->getNumVBases() || BaseMorallyVirtual)
-          && !NonVirtualPrimaryBase) {
-        llvm::Constant *init;
-        if (BaseMorallyVirtual || VtblClass == Class)
-          init = BuildVtablePtr(vtbl, VtblClass, Base, BaseOffset);
-        else {
-          init = getCtorVtable(BaseSubobject(Base, BaseOffset));
-          
-          subvtbl = init;
-          subVtblClass = Base;
-          
-          init = BuildVtablePtr(init, Class, Base, BaseOffset);
-        }
-
-        Inits.push_back(init);
-      }
-      
-      if (i->isVirtual())
-        SeenVBasesInSecondary.insert(Base);
-      
-      Secondary(Base, subvtbl, subVtblClass, BaseOffset, BaseMorallyVirtual);
-    }
-  }
-
-  /// BuiltVTT - Add the VTT to Inits.  Offset is the offset in bits to the
-  /// currnet object we're working on.
-  void BuildVTT(const CXXRecordDecl *RD, uint64_t Offset, bool MorallyVirtual) {
-    // 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;
-
-    // Remember the sub-VTT index.
-    SubVTTIndicies[RD] = Inits.size();
-
-    llvm::Constant *Vtable;
-    const CXXRecordDecl *VtableClass;
-
-    // First comes the primary virtual table pointer...
-    if (MorallyVirtual) {
-      Vtable = ClassVtbl;
-      VtableClass = Class;
-    } else {
-      Vtable = getCtorVtable(BaseSubobject(RD, Offset));
-      VtableClass = RD;
-    }
-    
-    llvm::Constant *Init = BuildVtablePtr(Vtable, VtableClass, RD, Offset);
-    Inits.push_back(Init);
-
-    // then the secondary VTTs....
-    SecondaryVTTs(RD, Offset, MorallyVirtual);
-
-    // Make sure to clear the set of seen virtual bases.
-    SeenVBasesInSecondary.clear();
-
-    // and last the secondary vtable pointers.
-    Secondary(RD, Vtable, VtableClass, Offset, MorallyVirtual);
-  }
-
-  /// SecondaryVTTs - Add the secondary VTTs to Inits.  The secondary VTTs are
-  /// built from each direct non-virtual proper base that requires a VTT in
-  /// declaration order.
-  void SecondaryVTTs(const CXXRecordDecl *RD, uint64_t Offset=0,
-                     bool MorallyVirtual=false) {
-    for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
-           e = RD->bases_end(); i != e; ++i) {
-      const CXXRecordDecl *Base =
-        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
-      if (i->isVirtual())
-        continue;
-      const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
-      uint64_t BaseOffset = Offset + Layout.getBaseClassOffset(Base);
-      
-      BuildVTT(Base, BaseOffset, MorallyVirtual);
-    }
-  }
-
-  /// VirtualVTTs - Add the VTT for each proper virtual base in inheritance
-  /// graph preorder.
-  void VirtualVTTs(const CXXRecordDecl *RD) {
-    for (CXXRecordDecl::base_class_const_iterator i = RD->bases_begin(),
-           e = RD->bases_end(); i != e; ++i) {
-      const CXXRecordDecl *Base =
-        cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
-      if (i->isVirtual() && !SeenVBase.count(Base)) {
-        SeenVBase.insert(Base);
-        uint64_t BaseOffset = BLayout.getVBaseClassOffset(Base);
-        BuildVTT(Base, BaseOffset, false);
-      }
-      VirtualVTTs(Base);
-    }
-  }
-
-public:
-  VTTBuilder(std::vector<llvm::Constant *> &inits, const CXXRecordDecl *c,
-             CodeGenModule &cgm, bool GenerateDefinition)
-    : Inits(inits), Class(c), CGM(cgm),
-      BLayout(cgm.getContext().getASTRecordLayout(c)),
-      AddressPoints(*cgm.getVtableInfo().AddressPoints[c]),
-      VMContext(cgm.getModule().getContext()),
-      GenerateDefinition(GenerateDefinition) {
-    
-    // First comes the primary virtual table pointer for the complete class...
-    ClassVtbl = GenerateDefinition ? CGM.getVtableInfo().getVtable(Class) : 0;
-
-    llvm::Constant *Init = BuildVtablePtr(ClassVtbl, Class, Class, 0);
-    Inits.push_back(Init);
-    
-    // then the secondary VTTs...
-    SecondaryVTTs(Class);
-
-    // Make sure to clear the set of seen virtual bases.
-    SeenVBasesInSecondary.clear();
-
-    // then the secondary vtable pointers...
-    Secondary(Class, ClassVtbl, Class);
-
-    // and last, the virtual VTTs.
-    VirtualVTTs(Class);
-  }
-  
-  llvm::DenseMap<const CXXRecordDecl *, uint64_t> &getSubVTTIndicies() {
-    return SubVTTIndicies;
-  }
-};
-}
-
-llvm::GlobalVariable *
-CGVtableInfo::GenerateVTT(llvm::GlobalVariable::LinkageTypes Linkage,
-                          bool GenerateDefinition,
-                          const CXXRecordDecl *RD) {
-  // Only classes that have virtual bases need a VTT.
-  if (RD->getNumVBases() == 0)
-    return 0;
-
-  llvm::SmallString<256> OutName;
-  CGM.getMangleContext().mangleCXXVTT(RD, OutName);
-  llvm::StringRef Name = OutName.str();
-
-  D1(printf("vtt %s\n", RD->getNameAsCString()));
-
-  llvm::GlobalVariable *GV = CGM.getModule().getGlobalVariable(Name);
-  if (GV == 0 || GV->isDeclaration()) {
-    const llvm::Type *Int8PtrTy = 
-      llvm::Type::getInt8PtrTy(CGM.getLLVMContext());
-
-    std::vector<llvm::Constant *> inits;
-    VTTBuilder b(inits, RD, CGM, GenerateDefinition);
-
-    const llvm::ArrayType *Type = llvm::ArrayType::get(Int8PtrTy, inits.size());
-    llvm::Constant *Init = 0;
-    if (GenerateDefinition)
-      Init = llvm::ConstantArray::get(Type, inits);
-
-    llvm::GlobalVariable *OldGV = GV;
-    GV = new llvm::GlobalVariable(CGM.getModule(), Type, /*isConstant=*/true, 
-                                  Linkage, Init, Name);
-    CGM.setGlobalVisibility(GV, RD);
-    
-    if (OldGV) {
-      GV->takeName(OldGV);
-      llvm::Constant *NewPtr = 
-        llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
-      OldGV->replaceAllUsesWith(NewPtr);
-      OldGV->eraseFromParent();
-    }
-  }
-  
-  return GV;
-}
-
 void CGVtableInfo::GenerateClassData(llvm::GlobalVariable::LinkageTypes Linkage,
                                      const CXXRecordDecl *RD) {
   llvm::GlobalVariable *&Vtable = Vtables[RD];
@@ -1547,25 +1232,6 @@ llvm::GlobalVariable *CGVtableInfo::getVtable(const CXXRecordDecl *RD) {
   return Vtable;
 }
 
-CGVtableInfo::CtorVtableInfo 
-CGVtableInfo::getCtorVtable(const CXXRecordDecl *RD, 
-                            const BaseSubobject &Base) {
-  CtorVtableInfo Info;
-  
-  Info.Vtable = GenerateVtable(llvm::GlobalValue::InternalLinkage,
-                               /*GenerateDefinition=*/true,
-                               RD, Base.getBase(), Base.getBaseOffset(),
-                               Info.AddressPoints);
-  return Info;
-}
- 
-llvm::GlobalVariable *CGVtableInfo::getVTT(const CXXRecordDecl *RD) {
-  return GenerateVTT(llvm::GlobalValue::ExternalLinkage, 
-                     /*GenerateDefinition=*/false, RD);
-  
-}
-
-
 void CGVtableInfo::MaybeEmitVtable(GlobalDecl GD) {
   const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
   const CXXRecordDecl *RD = MD->getParent();
@@ -1599,47 +1265,3 @@ void CGVtableInfo::MaybeEmitVtable(GlobalDecl GD) {
   }
 }
 
-bool CGVtableInfo::needsVTTParameter(GlobalDecl GD) {
-  const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
-  
-  // We don't have any virtual bases, just return early.
-  if (!MD->getParent()->getNumVBases())
-    return false;
-  
-  // Check if we have a base constructor.
-  if (isa<CXXConstructorDecl>(MD) && GD.getCtorType() == Ctor_Base)
-    return true;
-
-  // Check if we have a base destructor.
-  if (isa<CXXDestructorDecl>(MD) && GD.getDtorType() == Dtor_Base)
-    return true;
-  
-  return false;
-}
-
-uint64_t CGVtableInfo::getSubVTTIndex(const CXXRecordDecl *RD, 
-                                      const CXXRecordDecl *Base) {
-  ClassPairTy ClassPair(RD, Base);
-
-  SubVTTIndiciesTy::iterator I = 
-    SubVTTIndicies.find(ClassPair);
-  if (I != SubVTTIndicies.end())
-    return I->second;
-  
-  std::vector<llvm::Constant *> inits;
-  VTTBuilder Builder(inits, RD, CGM, /*GenerateDefinition=*/false);
-
-  for (llvm::DenseMap<const CXXRecordDecl *, uint64_t>::iterator I =
-       Builder.getSubVTTIndicies().begin(), 
-       E = Builder.getSubVTTIndicies().end(); I != E; ++I) {
-    // Insert all indices.
-    ClassPairTy ClassPair(RD, I->first);
-    
-    SubVTTIndicies.insert(std::make_pair(ClassPair, I->second));
-  }
-    
-  I = SubVTTIndicies.find(ClassPair);
-  assert(I != SubVTTIndicies.end() && "Did not find index!");
-  
-  return I->second;
-}
diff --git a/clang/lib/CodeGen/CMakeLists.txt b/clang/lib/CodeGen/CMakeLists.txt
index 45469d39e4a..e72a1d9e094 100644
--- a/clang/lib/CodeGen/CMakeLists.txt
+++ b/clang/lib/CodeGen/CMakeLists.txt
@@ -24,6 +24,7 @@ add_clang_library(clangCodeGen
   CGStmt.cpp
   CGTemporaries.cpp
   CGVtable.cpp
+  CGVTT.cpp
   CodeGenFunction.cpp
   CodeGenModule.cpp
   CodeGenTypes.cpp