Update clang to r84119.

1 files changed, 627 insertions, 241 deletions

diff --git a/lib/CodeGen/CGExprConstant.cpp b/lib/CodeGen/CGExprConstant.cpp
index 37c9c36..7f540c3 100644
--- a/lib/CodeGen/CGExprConstant.cpp
+++ b/lib/CodeGen/CGExprConstant.cpp
@@ -16,6 +16,7 @@
 #include "CGObjCRuntime.h"
 #include "clang/AST/APValue.h"
 #include "clang/AST/ASTContext.h"
+#include "clang/AST/RecordLayout.h"
 #include "clang/AST/StmtVisitor.h"
 #include "clang/Basic/Builtins.h"
 #include "llvm/Constants.h"
@@ -27,45 +28,541 @@ using namespace clang;
 using namespace CodeGen;
 
 namespace  {
-class VISIBILITY_HIDDEN ConstExprEmitter : 
+
+class VISIBILITY_HIDDEN ConstStructBuilder {
+  CodeGenModule &CGM;
+  CodeGenFunction *CGF;
+
+  bool Packed;
+
+  unsigned NextFieldOffsetInBytes;
+
+  unsigned LLVMStructAlignment;
+  
+  std::vector<llvm::Constant *> Elements;
+
+  ConstStructBuilder(CodeGenModule &CGM, CodeGenFunction *CGF)
+    : CGM(CGM), CGF(CGF), Packed(false), NextFieldOffsetInBytes(0),
+    LLVMStructAlignment(1) { }
+
+  bool AppendField(const FieldDecl *Field, uint64_t FieldOffset,
+                   const Expr *InitExpr) {
+    uint64_t FieldOffsetInBytes = FieldOffset / 8;
+
+    assert(NextFieldOffsetInBytes <= FieldOffsetInBytes
+           && "Field offset mismatch!");
+
+    // Emit the field.
+    llvm::Constant *C = CGM.EmitConstantExpr(InitExpr, Field->getType(), CGF);
+    if (!C)
+      return false;
+
+    unsigned FieldAlignment = getAlignment(C);
+
+    // Round up the field offset to the alignment of the field type.
+    uint64_t AlignedNextFieldOffsetInBytes =
+      llvm::RoundUpToAlignment(NextFieldOffsetInBytes, FieldAlignment);
+
+    if (AlignedNextFieldOffsetInBytes > FieldOffsetInBytes) {
+      assert(!Packed && "Alignment is wrong even with a packed struct!");
+
+      // Convert the struct to a packed struct.
+      ConvertStructToPacked();
+      
+      AlignedNextFieldOffsetInBytes = NextFieldOffsetInBytes;
+    }
+
+    if (AlignedNextFieldOffsetInBytes < FieldOffsetInBytes) {
+      // We need to append padding.
+      AppendPadding(FieldOffsetInBytes - NextFieldOffsetInBytes);
+
+      assert(NextFieldOffsetInBytes == FieldOffsetInBytes &&
+             "Did not add enough padding!");
+
+      AlignedNextFieldOffsetInBytes = NextFieldOffsetInBytes;
+    }
+
+    // Add the field.
+    Elements.push_back(C);
+    NextFieldOffsetInBytes = AlignedNextFieldOffsetInBytes + getSizeInBytes(C);
+    
+    if (Packed)
+      assert(LLVMStructAlignment == 1 && "Packed struct not byte-aligned!");
+    else
+      LLVMStructAlignment = std::max(LLVMStructAlignment, FieldAlignment);
+
+    return true;
+  }
+
+  bool AppendBitField(const FieldDecl *Field, uint64_t FieldOffset,
+                      const Expr *InitExpr) {
+    llvm::ConstantInt *CI =
+      cast_or_null<llvm::ConstantInt>(CGM.EmitConstantExpr(InitExpr,
+                                                           Field->getType(),
+                                                           CGF));
+    // FIXME: Can this ever happen?
+    if (!CI)
+      return false;
+
+    if (FieldOffset > NextFieldOffsetInBytes * 8) {
+      // We need to add padding.
+      uint64_t NumBytes =
+        llvm::RoundUpToAlignment(FieldOffset -
+                                 NextFieldOffsetInBytes * 8, 8) / 8;
+
+      AppendPadding(NumBytes);
+    }
+
+    uint64_t FieldSize =
+      Field->getBitWidth()->EvaluateAsInt(CGM.getContext()).getZExtValue();
+
+    llvm::APInt FieldValue = CI->getValue();
+
+    // Promote the size of FieldValue if necessary
+    // FIXME: This should never occur, but currently it can because initializer
+    // constants are cast to bool, and because clang is not enforcing bitfield
+    // width limits.
+    if (FieldSize > FieldValue.getBitWidth())
+      FieldValue.zext(FieldSize);
+
+    // Truncate the size of FieldValue to the bit field size.
+    if (FieldSize < FieldValue.getBitWidth())
+      FieldValue.trunc(FieldSize);
+
+    if (FieldOffset < NextFieldOffsetInBytes * 8) {
+      // Either part of the field or the entire field can go into the previous
+      // byte.
+      assert(!Elements.empty() && "Elements can't be empty!");
+
+      unsigned BitsInPreviousByte =
+        NextFieldOffsetInBytes * 8 - FieldOffset;
+
+      bool FitsCompletelyInPreviousByte =
+        BitsInPreviousByte >= FieldValue.getBitWidth();
+
+      llvm::APInt Tmp = FieldValue;
+
+      if (!FitsCompletelyInPreviousByte) {
+        unsigned NewFieldWidth = FieldSize - BitsInPreviousByte;
+
+        if (CGM.getTargetData().isBigEndian()) {
+          Tmp = Tmp.lshr(NewFieldWidth);
+          Tmp.trunc(BitsInPreviousByte);
+
+          // We want the remaining high bits.
+          FieldValue.trunc(NewFieldWidth);
+        } else {
+          Tmp.trunc(BitsInPreviousByte);
+
+          // We want the remaining low bits.
+          FieldValue = FieldValue.lshr(BitsInPreviousByte);
+          FieldValue.trunc(NewFieldWidth);
+        }
+      }
+
+      Tmp.zext(8);
+      if (CGM.getTargetData().isBigEndian()) {
+        if (FitsCompletelyInPreviousByte)
+          Tmp = Tmp.shl(BitsInPreviousByte - FieldValue.getBitWidth());
+      } else {
+        Tmp = Tmp.shl(8 - BitsInPreviousByte);
+      }
+
+      // Or in the bits that go into the previous byte.
+      Tmp |= cast<llvm::ConstantInt>(Elements.back())->getValue();
+      Elements.back() = llvm::ConstantInt::get(CGM.getLLVMContext(), Tmp);
+
+      if (FitsCompletelyInPreviousByte)
+        return true;
+    }
+
+    while (FieldValue.getBitWidth() > 8) {
+      llvm::APInt Tmp;
+
+      if (CGM.getTargetData().isBigEndian()) {
+        // We want the high bits.
+        Tmp = FieldValue;
+        Tmp = Tmp.lshr(Tmp.getBitWidth() - 8);
+        Tmp.trunc(8);
+      } else {
+        // We want the low bits.
+        Tmp = FieldValue;
+        Tmp.trunc(8);
+
+        FieldValue = FieldValue.lshr(8);
+      }
+
+      Elements.push_back(llvm::ConstantInt::get(CGM.getLLVMContext(), Tmp));
+      NextFieldOffsetInBytes++;
+
+      FieldValue.trunc(FieldValue.getBitWidth() - 8);
+    }
+
+    assert(FieldValue.getBitWidth() > 0 &&
+           "Should have at least one bit left!");
+    assert(FieldValue.getBitWidth() <= 8 &&
+           "Should not have more than a byte left!");
+
+    if (FieldValue.getBitWidth() < 8) {
+      if (CGM.getTargetData().isBigEndian()) {
+        unsigned BitWidth = FieldValue.getBitWidth();
+
+        FieldValue.zext(8);
+        FieldValue = FieldValue << (8 - BitWidth);
+      } else
+        FieldValue.zext(8);
+    }
+
+    // Append the last element.
+    Elements.push_back(llvm::ConstantInt::get(CGM.getLLVMContext(),
+                                              FieldValue));
+    NextFieldOffsetInBytes++;
+    return true;
+  }
+
+  void AppendPadding(uint64_t NumBytes) {
+    if (!NumBytes)
+      return;
+
+    const llvm::Type *Ty = llvm::Type::getInt8Ty(CGM.getLLVMContext());
+    if (NumBytes > 1)
+      Ty = llvm::ArrayType::get(Ty, NumBytes);
+
+    llvm::Constant *C = llvm::Constant::getNullValue(Ty);
+    Elements.push_back(C);
+    assert(getAlignment(C) == 1 && "Padding must have 1 byte alignment!");
+
+    NextFieldOffsetInBytes += getSizeInBytes(C);
+  }
+
+  void AppendTailPadding(uint64_t RecordSize) {
+    assert(RecordSize % 8 == 0 && "Invalid record size!");
+
+    uint64_t RecordSizeInBytes = RecordSize / 8;
+    assert(NextFieldOffsetInBytes <= RecordSizeInBytes && "Size mismatch!");
+
+    unsigned NumPadBytes = RecordSizeInBytes - NextFieldOffsetInBytes;
+    AppendPadding(NumPadBytes);
+  }
+
+  void ConvertStructToPacked() {
+    std::vector<llvm::Constant *> PackedElements;
+    uint64_t ElementOffsetInBytes = 0;
+
+    for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
+      llvm::Constant *C = Elements[i];
+
+      unsigned ElementAlign =
+        CGM.getTargetData().getABITypeAlignment(C->getType());
+      uint64_t AlignedElementOffsetInBytes =
+        llvm::RoundUpToAlignment(ElementOffsetInBytes, ElementAlign);
+
+      if (AlignedElementOffsetInBytes > ElementOffsetInBytes) {
+        // We need some padding.
+        uint64_t NumBytes =
+          AlignedElementOffsetInBytes - ElementOffsetInBytes;
+
+        const llvm::Type *Ty = llvm::Type::getInt8Ty(CGF->getLLVMContext());
+        if (NumBytes > 1)
+          Ty = llvm::ArrayType::get(Ty, NumBytes);
+
+        llvm::Constant *Padding = llvm::Constant::getNullValue(Ty);
+        PackedElements.push_back(Padding);
+        ElementOffsetInBytes += getSizeInBytes(Padding);
+      }
+
+      PackedElements.push_back(C);
+      ElementOffsetInBytes += getSizeInBytes(C);
+    }
+
+    assert(ElementOffsetInBytes == NextFieldOffsetInBytes &&
+           "Packing the struct changed its size!");
+
+    Elements = PackedElements;
+    LLVMStructAlignment = 1;
+    Packed = true;
+  }
+                              
+  bool Build(InitListExpr *ILE) {
+    RecordDecl *RD = ILE->getType()->getAs<RecordType>()->getDecl();
+    const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(RD);
+
+    unsigned FieldNo = 0;
+    unsigned ElementNo = 0;
+    for (RecordDecl::field_iterator Field = RD->field_begin(),
+         FieldEnd = RD->field_end();
+         ElementNo < ILE->getNumInits() && Field != FieldEnd;
+         ++Field, ++FieldNo) {
+      if (RD->isUnion() && ILE->getInitializedFieldInUnion() != *Field)
+        continue;
+
+      if (Field->isBitField()) {
+        if (!Field->getIdentifier())
+          continue;
+
+        if (!AppendBitField(*Field, Layout.getFieldOffset(FieldNo),
+                            ILE->getInit(ElementNo)))
+          return false;
+      } else {
+        if (!AppendField(*Field, Layout.getFieldOffset(FieldNo),
+                         ILE->getInit(ElementNo)))
+          return false;
+      }
+
+      ElementNo++;
+    }
+
+    uint64_t LayoutSizeInBytes = Layout.getSize() / 8;
+
+    if (NextFieldOffsetInBytes > LayoutSizeInBytes) {
+      // If the struct is bigger than the size of the record type,
+      // we must have a flexible array member at the end.
+      assert(RD->hasFlexibleArrayMember() &&
+             "Must have flexible array member if struct is bigger than type!");
+      
+      // No tail padding is necessary.
+      return true;
+    }
+
+    uint64_t LLVMSizeInBytes = llvm::RoundUpToAlignment(NextFieldOffsetInBytes, 
+                                                        LLVMStructAlignment);
+
+    // Check if we need to convert the struct to a packed struct.
+    if (NextFieldOffsetInBytes <= LayoutSizeInBytes && 
+        LLVMSizeInBytes > LayoutSizeInBytes) {
+      assert(!Packed && "Size mismatch!");
+      
+      ConvertStructToPacked();
+      assert(NextFieldOffsetInBytes == LayoutSizeInBytes &&
+             "Converting to packed did not help!");
+    }
+
+    // Append tail padding if necessary.
+    AppendTailPadding(Layout.getSize());
+
+    assert(Layout.getSize() / 8 == NextFieldOffsetInBytes &&
+           "Tail padding mismatch!");
+
+    return true;
+  }
+
+  unsigned getAlignment(const llvm::Constant *C) const {
+    if (Packed)
+      return 1;
+
+    return CGM.getTargetData().getABITypeAlignment(C->getType());
+  }
+
+  uint64_t getSizeInBytes(const llvm::Constant *C) const {
+    return CGM.getTargetData().getTypeAllocSize(C->getType());
+  }
+
+public:
+  static llvm::Constant *BuildStruct(CodeGenModule &CGM, CodeGenFunction *CGF,
+                                     InitListExpr *ILE) {
+    ConstStructBuilder Builder(CGM, CGF);
+
+    if (!Builder.Build(ILE))
+      return 0;
+
+    llvm::Constant *Result =
+      llvm::ConstantStruct::get(CGM.getLLVMContext(),
+                                Builder.Elements, Builder.Packed);
+
+    assert(llvm::RoundUpToAlignment(Builder.NextFieldOffsetInBytes,
+                                    Builder.getAlignment(Result)) ==
+           Builder.getSizeInBytes(Result) && "Size mismatch!");
+
+    return Result;
+  }
+};
+
+class VISIBILITY_HIDDEN ConstExprEmitter :
   public StmtVisitor<ConstExprEmitter, llvm::Constant*> {
   CodeGenModule &CGM;
   CodeGenFunction *CGF;
+  llvm::LLVMContext &VMContext;
 public:
   ConstExprEmitter(CodeGenModule &cgm, CodeGenFunction *cgf)
-    : CGM(cgm), CGF(cgf) {
+    : CGM(cgm), CGF(cgf), VMContext(cgm.getLLVMContext()) {
   }
-    
+
   //===--------------------------------------------------------------------===//
   //                            Visitor Methods
   //===--------------------------------------------------------------------===//
-    
+
   llvm::Constant *VisitStmt(Stmt *S) {
     return 0;
   }
-  
-  llvm::Constant *VisitParenExpr(ParenExpr *PE) { 
-    return Visit(PE->getSubExpr()); 
+
+  llvm::Constant *VisitParenExpr(ParenExpr *PE) {
+    return Visit(PE->getSubExpr());
   }
-    
+
   llvm::Constant *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
     return Visit(E->getInitializer());
   }
-  
+    
+  llvm::Constant *EmitMemberFunctionPointer(CXXMethodDecl *MD) {
+    assert(MD->isInstance() && "Member function must not be static!");
+    
+    const llvm::Type *PtrDiffTy = 
+      CGM.getTypes().ConvertType(CGM.getContext().getPointerDiffType());
+    
+    llvm::Constant *Values[2];
+    
+    // Get the function pointer (or index if this is a virtual function).
+    if (MD->isVirtual()) {
+      int64_t Index = CGM.getVtableInfo().getMethodVtableIndex(MD);
+      
+      Values[0] = llvm::ConstantInt::get(PtrDiffTy, Index + 1);
+    } else {
+      llvm::Constant *FuncPtr = CGM.GetAddrOfFunction(MD);
+
+      Values[0] = llvm::ConstantExpr::getPtrToInt(FuncPtr, PtrDiffTy);
+    } 
+    
+    // The adjustment will always be 0.
+    Values[1] = llvm::ConstantInt::get(PtrDiffTy, 0);
+    
+    return llvm::ConstantStruct::get(CGM.getLLVMContext(),
+                                     Values, 2, /*Packed=*/false);
+  }
+
+  llvm::Constant *VisitUnaryAddrOf(UnaryOperator *E) {
+    if (const MemberPointerType *MPT = 
+        E->getType()->getAs<MemberPointerType>()) {
+      QualType T = MPT->getPointeeType();
+      if (T->isFunctionProtoType()) {
+        QualifiedDeclRefExpr *DRE = cast<QualifiedDeclRefExpr>(E->getSubExpr());
+        
+        return EmitMemberFunctionPointer(cast<CXXMethodDecl>(DRE->getDecl()));
+      }
+      
+      // FIXME: Should we handle other member pointer types here too,
+      // or should they be handled by Expr::Evaluate?
+    }
+    
+    return 0;
+  }
+    
+  llvm::Constant *VisitBinSub(BinaryOperator *E) {
+    // This must be a pointer/pointer subtraction.  This only happens for
+    // address of label.
+    if (!isa<AddrLabelExpr>(E->getLHS()->IgnoreParenNoopCasts(CGM.getContext())) ||
+       !isa<AddrLabelExpr>(E->getRHS()->IgnoreParenNoopCasts(CGM.getContext())))
+      return 0;
+    
+    llvm::Constant *LHS = CGM.EmitConstantExpr(E->getLHS(),
+                                               E->getLHS()->getType(), CGF);
+    llvm::Constant *RHS = CGM.EmitConstantExpr(E->getRHS(),
+                                               E->getRHS()->getType(), CGF);
+
+    const llvm::Type *ResultType = ConvertType(E->getType());
+    LHS = llvm::ConstantExpr::getPtrToInt(LHS, ResultType);
+    RHS = llvm::ConstantExpr::getPtrToInt(RHS, ResultType);
+        
+    // No need to divide by element size, since addr of label is always void*,
+    // which has size 1 in GNUish.
+    return llvm::ConstantExpr::getSub(LHS, RHS);
+  }
+    
   llvm::Constant *VisitCastExpr(CastExpr* E) {
-    // GCC cast to union extension
-    if (E->getType()->isUnionType()) {
+    switch (E->getCastKind()) {
+    case CastExpr::CK_ToUnion: {
+      // GCC cast to union extension
+      assert(E->getType()->isUnionType() &&
+             "Destination type is not union type!");
       const llvm::Type *Ty = ConvertType(E->getType());
       Expr *SubExpr = E->getSubExpr();
-      return EmitUnion(CGM.EmitConstantExpr(SubExpr, SubExpr->getType(), CGF), 
-                       Ty);
+
+      llvm::Constant *C =
+        CGM.EmitConstantExpr(SubExpr, SubExpr->getType(), CGF);
+      if (!C)
+        return 0;
+
+      // Build a struct with the union sub-element as the first member,
+      // and padded to the appropriate size
+      std::vector<llvm::Constant*> Elts;
+      std::vector<const llvm::Type*> Types;
+      Elts.push_back(C);
+      Types.push_back(C->getType());
+      unsigned CurSize = CGM.getTargetData().getTypeAllocSize(C->getType());
+      unsigned TotalSize = CGM.getTargetData().getTypeAllocSize(Ty);
+
+      assert(CurSize <= TotalSize && "Union size mismatch!");
+      if (unsigned NumPadBytes = TotalSize - CurSize) {
+        const llvm::Type *Ty = llvm::Type::getInt8Ty(VMContext);
+        if (NumPadBytes > 1)
+          Ty = llvm::ArrayType::get(Ty, NumPadBytes);
+
+        Elts.push_back(llvm::Constant::getNullValue(Ty));
+        Types.push_back(Ty);
+      }
+
+      llvm::StructType* STy =
+        llvm::StructType::get(C->getType()->getContext(), Types, false);
+      return llvm::ConstantStruct::get(STy, Elts);
+    }
+    case CastExpr::CK_NullToMemberPointer:
+      return CGM.EmitNullConstant(E->getType());
+      
+    case CastExpr::CK_BaseToDerivedMemberPointer: {
+      Expr *SubExpr = E->getSubExpr();
+
+      const MemberPointerType *SrcTy = 
+        SubExpr->getType()->getAs<MemberPointerType>();
+      const MemberPointerType *DestTy = 
+        E->getType()->getAs<MemberPointerType>();
+      
+      const CXXRecordDecl *BaseClass =
+        cast<CXXRecordDecl>(cast<RecordType>(SrcTy->getClass())->getDecl());
+      const CXXRecordDecl *DerivedClass =
+        cast<CXXRecordDecl>(cast<RecordType>(DestTy->getClass())->getDecl());
+
+      if (SrcTy->getPointeeType()->isFunctionProtoType()) {
+        llvm::Constant *C = 
+          CGM.EmitConstantExpr(SubExpr, SubExpr->getType(), CGF);
+        if (!C)
+          return 0;
+        
+        llvm::ConstantStruct *CS = cast<llvm::ConstantStruct>(C);
+        
+        // Check if we need to update the adjustment.
+        if (llvm::Constant *Offset = CGM.GetCXXBaseClassOffset(DerivedClass,
+                                                               BaseClass)) {
+          llvm::Constant *Values[2];
+        
+          Values[0] = CS->getOperand(0);
+          Values[1] = llvm::ConstantExpr::getAdd(CS->getOperand(1), Offset);
+          return llvm::ConstantStruct::get(CGM.getLLVMContext(), Values, 2, 
+                                           /*Packed=*/false);
+        }
+        
+        return CS;
+      }          
+    }
+        
+    default: {
+      // FIXME: This should be handled by the CK_NoOp cast kind.
+      // Explicit and implicit no-op casts
+      QualType Ty = E->getType(), SubTy = E->getSubExpr()->getType();
+      if (CGM.getContext().hasSameUnqualifiedType(Ty, SubTy))
+        return Visit(E->getSubExpr());
+
+      // Handle integer->integer casts for address-of-label differences.
+      if (Ty->isIntegerType() && SubTy->isIntegerType() &&
+          CGF) {
+        llvm::Value *Src = Visit(E->getSubExpr());
+        if (Src == 0) return 0;
+        
+        // Use EmitScalarConversion to perform the conversion.
+        return cast<llvm::Constant>(CGF->EmitScalarConversion(Src, SubTy, Ty));
+      }
+      
+      return 0;
     }
-    // Explicit and implicit no-op casts
-    QualType Ty = E->getType(), SubTy = E->getSubExpr()->getType();
-    if (CGM.getContext().hasSameUnqualifiedType(Ty, SubTy)) {
-      return Visit(E->getSubExpr());
     }
-    return 0;
   }
 
   llvm::Constant *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
@@ -79,7 +576,7 @@ public:
     unsigned NumInitElements = ILE->getNumInits();
     // FIXME: Check for wide strings
     // FIXME: Check for NumInitElements exactly equal to 1??
-    if (NumInitElements > 0 && 
+    if (NumInitElements > 0 &&
         (isa<StringLiteral>(ILE->getInit(0)) ||
          isa<ObjCEncodeExpr>(ILE->getInit(0))) &&
         ILE->getType()->getArrayElementTypeNoTypeQual()->isCharType())
@@ -87,7 +584,7 @@ public:
     const llvm::Type *ElemTy = AType->getElementType();
     unsigned NumElements = AType->getNumElements();
 
-    // Initialising an array requires us to automatically 
+    // Initialising an array requires us to automatically
     // initialise any elements that have not been initialised explicitly
     unsigned NumInitableElts = std::min(NumInitElements, NumElements);
 
@@ -113,184 +610,20 @@ public:
       std::vector<const llvm::Type*> Types;
       for (unsigned i = 0; i < Elts.size(); ++i)
         Types.push_back(Elts[i]->getType());
-      const llvm::StructType *SType = llvm::StructType::get(Types, true);
+      const llvm::StructType *SType = llvm::StructType::get(AType->getContext(),
+                                                            Types, true);
       return llvm::ConstantStruct::get(SType, Elts);
     }
 
-    return llvm::ConstantArray::get(AType, Elts);    
-  }
-
-  void InsertBitfieldIntoStruct(std::vector<llvm::Constant*>& Elts,
-                                FieldDecl* Field, Expr* E) {
-    // Calculate the value to insert
-    llvm::Constant *C = CGM.EmitConstantExpr(E, Field->getType(), CGF);
-    if (!C)
-      return;
-
-    llvm::ConstantInt *CI = dyn_cast<llvm::ConstantInt>(C);
-    if (!CI) {
-      CGM.ErrorUnsupported(E, "bitfield initialization");
-      return;
-    }
-    llvm::APInt V = CI->getValue();
-
-    // Calculate information about the relevant field
-    const llvm::Type* Ty = CI->getType();
-    const llvm::TargetData &TD = CGM.getTypes().getTargetData();
-    unsigned size = TD.getTypeAllocSizeInBits(Ty);
-    unsigned fieldOffset = CGM.getTypes().getLLVMFieldNo(Field) * size;
-    CodeGenTypes::BitFieldInfo bitFieldInfo =
-        CGM.getTypes().getBitFieldInfo(Field);
-    fieldOffset += bitFieldInfo.Begin;
-
-    // Find where to start the insertion
-    // FIXME: This is O(n^2) in the number of bit-fields!
-    // FIXME: This won't work if the struct isn't completely packed!
-    unsigned offset = 0, i = 0;
-    while (offset < (fieldOffset & -8))
-      offset += TD.getTypeAllocSizeInBits(Elts[i++]->getType());
-
-    // Advance over 0 sized elements (must terminate in bounds since
-    // the bitfield must have a size).
-    while (TD.getTypeAllocSizeInBits(Elts[i]->getType()) == 0)
-      ++i;
-
-    // Promote the size of V if necessary
-    // FIXME: This should never occur, but currently it can because initializer
-    // constants are cast to bool, and because clang is not enforcing bitfield
-    // width limits.
-    if (bitFieldInfo.Size > V.getBitWidth())
-      V.zext(bitFieldInfo.Size);
-
-    // Insert the bits into the struct
-    // FIXME: This algorthm is only correct on X86!
-    // FIXME: THis algorthm assumes bit-fields only have byte-size elements!
-    unsigned bitsToInsert = bitFieldInfo.Size;
-    unsigned curBits = std::min(8 - (fieldOffset & 7), bitsToInsert);
-    unsigned byte = V.getLoBits(curBits).getZExtValue() << (fieldOffset & 7);
-    do {
-      llvm::Constant* byteC = llvm::ConstantInt::get(llvm::Type::Int8Ty, byte);
-      Elts[i] = llvm::ConstantExpr::getOr(Elts[i], byteC);
-      ++i;
-      V = V.lshr(curBits);
-      bitsToInsert -= curBits;
-
-      if (!bitsToInsert)
-        break;
-
-      curBits = bitsToInsert > 8 ? 8 : bitsToInsert;
-      byte = V.getLoBits(curBits).getZExtValue();
-    } while (true);
+    return llvm::ConstantArray::get(AType, Elts);
   }
 
   llvm::Constant *EmitStructInitialization(InitListExpr *ILE) {
-    const llvm::StructType *SType =
-        cast<llvm::StructType>(ConvertType(ILE->getType()));
-    RecordDecl *RD = ILE->getType()->getAsRecordType()->getDecl();
-    std::vector<llvm::Constant*> Elts;
-
-    // Initialize the whole structure to zero.
-    // FIXME: This doesn't handle member pointers correctly!
-    for (unsigned i = 0; i < SType->getNumElements(); ++i) {
-      const llvm::Type *FieldTy = SType->getElementType(i);
-      Elts.push_back(llvm::Constant::getNullValue(FieldTy));
-    }
-
-    // Copy initializer elements. Skip padding fields.
-    unsigned EltNo = 0;  // Element no in ILE
-    bool RewriteType = false;
-    for (RecordDecl::field_iterator Field = RD->field_begin(),
-                                 FieldEnd = RD->field_end();
-         EltNo < ILE->getNumInits() && Field != FieldEnd; ++Field) {
-      if (Field->isBitField()) {
-        if (!Field->getIdentifier())
-          continue;
-        InsertBitfieldIntoStruct(Elts, *Field, ILE->getInit(EltNo));
-      } else {
-        unsigned FieldNo = CGM.getTypes().getLLVMFieldNo(*Field);
-        llvm::Constant *C = CGM.EmitConstantExpr(ILE->getInit(EltNo), 
-                                                 Field->getType(), CGF);
-        if (!C) return 0;
-        RewriteType |= (C->getType() != Elts[FieldNo]->getType());
-        Elts[FieldNo] = C;
-      }
-      EltNo++;
-    }
-
-    if (RewriteType) {
-      // FIXME: Make this work for non-packed structs
-      assert(SType->isPacked() && "Cannot recreate unpacked structs");
-      std::vector<const llvm::Type*> Types;
-      for (unsigned i = 0; i < Elts.size(); ++i)
-        Types.push_back(Elts[i]->getType());
-      SType = llvm::StructType::get(Types, true);
-    }
-
-    return llvm::ConstantStruct::get(SType, Elts);
-  }
-
-  llvm::Constant *EmitUnion(llvm::Constant *C, const llvm::Type *Ty) {
-    if (!C)
-      return 0;
-
-    // Build a struct with the union sub-element as the first member,
-    // and padded to the appropriate size
-    std::vector<llvm::Constant*> Elts;
-    std::vector<const llvm::Type*> Types;
-    Elts.push_back(C);
-    Types.push_back(C->getType());
-    unsigned CurSize = CGM.getTargetData().getTypeAllocSize(C->getType());
-    unsigned TotalSize = CGM.getTargetData().getTypeAllocSize(Ty);
-    while (CurSize < TotalSize) {
-      Elts.push_back(llvm::Constant::getNullValue(llvm::Type::Int8Ty));
-      Types.push_back(llvm::Type::Int8Ty);
-      CurSize++;
-    }
-
-    // This always generates a packed struct
-    // FIXME: Try to generate an unpacked struct when we can
-    llvm::StructType* STy = llvm::StructType::get(Types, true);
-    return llvm::ConstantStruct::get(STy, Elts);
+    return ConstStructBuilder::BuildStruct(CGM, CGF, ILE);
   }
 
   llvm::Constant *EmitUnionInitialization(InitListExpr *ILE) {
-    const llvm::Type *Ty = ConvertType(ILE->getType());
-
-    FieldDecl* curField = ILE->getInitializedFieldInUnion();
-    if (!curField) {
-      // There's no field to initialize, so value-initialize the union.
-#ifndef NDEBUG
-      // Make sure that it's really an empty and not a failure of
-      // semantic analysis.
-      RecordDecl *RD = ILE->getType()->getAsRecordType()->getDecl();
-      for (RecordDecl::field_iterator Field = RD->field_begin(),
-                                   FieldEnd = RD->field_end();
-           Field != FieldEnd; ++Field)
-        assert(Field->isUnnamedBitfield() && "Only unnamed bitfields allowed");
-#endif
-      return llvm::Constant::getNullValue(Ty);
-    }
-
-    if (curField->isBitField()) {
-      // Create a dummy struct for bit-field insertion
-      unsigned NumElts = CGM.getTargetData().getTypeAllocSize(Ty);
-      llvm::Constant* NV = llvm::Constant::getNullValue(llvm::Type::Int8Ty);
-      std::vector<llvm::Constant*> Elts(NumElts, NV);
-
-      InsertBitfieldIntoStruct(Elts, curField, ILE->getInit(0));
-      const llvm::ArrayType *RetTy =
-          llvm::ArrayType::get(NV->getType(), NumElts);
-      return llvm::ConstantArray::get(RetTy, Elts);
-    }
-
-    llvm::Constant *InitElem;
-    if (ILE->getNumInits() > 0) {
-      Expr *Init = ILE->getInit(0);
-      InitElem = CGM.EmitConstantExpr(Init, Init->getType(), CGF);
-    } else {
-      InitElem = CGM.EmitNullConstant(curField->getType());
-    }
-    return EmitUnion(InitElem, Ty);
+    return ConstStructBuilder::BuildStruct(CGM, CGF, ILE);
   }
 
   llvm::Constant *EmitVectorInitialization(InitListExpr *ILE) {
@@ -316,13 +649,13 @@ public:
     for (; i < NumElements; ++i)
       Elts.push_back(llvm::Constant::getNullValue(ElemTy));
 
-    return llvm::ConstantVector::get(VType, Elts);    
+    return llvm::ConstantVector::get(VType, Elts);
   }
-  
+
   llvm::Constant *VisitImplicitValueInitExpr(ImplicitValueInitExpr* E) {
     return CGM.EmitNullConstant(E->getType());
   }
-    
+
   llvm::Constant *VisitInitListExpr(InitListExpr *ILE) {
     if (ILE->getType()->isScalarType()) {
       // We have a scalar in braces. Just use the first element.
@@ -332,7 +665,7 @@ public:
       }
       return CGM.EmitNullConstant(ILE->getType());
     }
-    
+
     if (ILE->getType()->isArrayType())
       return EmitArrayInitialization(ILE);
 
@@ -353,11 +686,12 @@ public:
 
   llvm::Constant *VisitStringLiteral(StringLiteral *E) {
     assert(!E->getType()->isPointerType() && "Strings are always arrays");
-    
+
     // This must be a string initializing an array in a static initializer.
     // Don't emit it as the address of the string, emit the string data itself
     // as an inline array.
-    return llvm::ConstantArray::get(CGM.GetStringForStringLiteral(E), false);
+    return llvm::ConstantArray::get(VMContext,
+                                    CGM.GetStringForStringLiteral(E), false);
   }
 
   llvm::Constant *VisitObjCEncodeExpr(ObjCEncodeExpr *E) {
@@ -367,13 +701,13 @@ public:
     std::string Str;
     CGM.getContext().getObjCEncodingForType(E->getEncodedType(), Str);
     const ConstantArrayType *CAT = cast<ConstantArrayType>(E->getType());
-    
+
     // Resize the string to the right size, adding zeros at the end, or
     // truncating as needed.
     Str.resize(CAT->getSize().getZExtValue(), '\0');
-    return llvm::ConstantArray::get(Str, false);
+    return llvm::ConstantArray::get(VMContext, Str, false);
   }
-    
+
   llvm::Constant *VisitUnaryExtension(const UnaryOperator *E) {
     return Visit(E->getSubExpr());
   }
@@ -394,20 +728,21 @@ public:
       llvm::Constant* C = Visit(CLE->getInitializer());
       // FIXME: "Leaked" on failure.
       if (C)
-        C = new llvm::GlobalVariable(C->getType(),
-                                     E->getType().isConstQualified(), 
+        C = new llvm::GlobalVariable(CGM.getModule(), C->getType(),
+                                     E->getType().isConstant(CGM.getContext()),
                                      llvm::GlobalValue::InternalLinkage,
-                                     C, ".compoundliteral", &CGM.getModule());
+                                     C, ".compoundliteral", 0, false,
+                                     E->getType().getAddressSpace());
       return C;
     }
-    case Expr::DeclRefExprClass: 
+    case Expr::DeclRefExprClass:
     case Expr::QualifiedDeclRefExprClass: {
       NamedDecl *Decl = cast<DeclRefExpr>(E)->getDecl();
       if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(Decl))
-        return CGM.GetAddrOfFunction(GlobalDecl(FD));
+        return CGM.GetAddrOfFunction(FD);
       if (const VarDecl* VD = dyn_cast<VarDecl>(Decl)) {
         // We can never refer to a variable with local storage.
-        if (!VD->hasLocalStorage()) {          
+        if (!VD->hasLocalStorage()) {
           if (VD->isFileVarDecl() || VD->hasExternalStorage())
             return CGM.GetAddrOfGlobalVar(VD);
           else if (VD->isBlockVarDecl()) {
@@ -430,21 +765,23 @@ public:
     case Expr::PredefinedExprClass: {
       // __func__/__FUNCTION__ -> "".  __PRETTY_FUNCTION__ -> "top level".
       std::string Str;
-      if (cast<PredefinedExpr>(E)->getIdentType() == 
+      if (cast<PredefinedExpr>(E)->getIdentType() ==
           PredefinedExpr::PrettyFunction)
         Str = "top level";
-      
+
       return CGM.GetAddrOfConstantCString(Str, ".tmp");
     }
     case Expr::AddrLabelExprClass: {
       assert(CGF && "Invalid address of label expression outside function.");
-      unsigned id = CGF->GetIDForAddrOfLabel(cast<AddrLabelExpr>(E)->getLabel());
-      llvm::Constant *C = llvm::ConstantInt::get(llvm::Type::Int32Ty, id);
+      unsigned id =
+          CGF->GetIDForAddrOfLabel(cast<AddrLabelExpr>(E)->getLabel());
+      llvm::Constant *C =
+            llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), id);
       return llvm::ConstantExpr::getIntToPtr(C, ConvertType(E->getType()));
     }
     case Expr::CallExprClass: {
       CallExpr* CE = cast<CallExpr>(E);
-      if (CE->isBuiltinCall(CGM.getContext()) != 
+      if (CE->isBuiltinCall(CGM.getContext()) !=
             Builtin::BI__builtin___CFStringMakeConstantString)
         break;
       const Expr *Arg = CE->getArg(0)->IgnoreParenCasts();
@@ -466,23 +803,23 @@ public:
     return 0;
   }
 };
-  
+
 }  // end anonymous namespace.
 
 llvm::Constant *CodeGenModule::EmitConstantExpr(const Expr *E,
                                                 QualType DestType,
                                                 CodeGenFunction *CGF) {
   Expr::EvalResult Result;
-  
+
   bool Success = false;
-  
+
   if (DestType->isReferenceType())
     Success = E->EvaluateAsLValue(Result, Context);
-  else 
+  else
     Success = E->Evaluate(Result, Context);
-  
+
   if (Success) {
-    assert(!Result.HasSideEffects && 
+    assert(!Result.HasSideEffects &&
            "Constant expr should not have any side effects!");
     switch (Result.Val.getKind()) {
     case APValue::Uninitialized:
@@ -490,18 +827,17 @@ llvm::Constant *CodeGenModule::EmitConstantExpr(const Expr *E,
       return 0;
     case APValue::LValue: {
       const llvm::Type *DestTy = getTypes().ConvertTypeForMem(DestType);
-      llvm::Constant *Offset = 
-        llvm::ConstantInt::get(llvm::Type::Int64Ty, 
+      llvm::Constant *Offset =
+        llvm::ConstantInt::get(llvm::Type::getInt64Ty(VMContext),
                                Result.Val.getLValueOffset());
-      
+
       llvm::Constant *C;
       if (const Expr *LVBase = Result.Val.getLValueBase()) {
         C = ConstExprEmitter(*this, CGF).EmitLValue(const_cast<Expr*>(LVBase));
 
         // Apply offset if necessary.
         if (!Offset->isNullValue()) {
-          const llvm::Type *Type = 
-            llvm::PointerType::getUnqual(llvm::Type::Int8Ty);
+          const llvm::Type *Type = llvm::Type::getInt8PtrTy(VMContext);
           llvm::Constant *Casted = llvm::ConstantExpr::getBitCast(C, Type);
           Casted = llvm::ConstantExpr::getGetElementPtr(Casted, &Offset, 1);
           C = llvm::ConstantExpr::getBitCast(Casted, C->getType());
@@ -529,9 +865,10 @@ llvm::Constant *CodeGenModule::EmitConstantExpr(const Expr *E,
       }
     }
     case APValue::Int: {
-      llvm::Constant *C = llvm::ConstantInt::get(Result.Val.getInt());
-      
-      if (C->getType() == llvm::Type::Int1Ty) {
+      llvm::Constant *C = llvm::ConstantInt::get(VMContext,
+                                                 Result.Val.getInt());
+
+      if (C->getType() == llvm::Type::getInt1Ty(VMContext)) {
         const llvm::Type *BoolTy = getTypes().ConvertTypeForMem(E->getType());
         C = llvm::ConstantExpr::getZExt(C, BoolTy);
       }
@@ -539,32 +876,38 @@ llvm::Constant *CodeGenModule::EmitConstantExpr(const Expr *E,
     }
     case APValue::ComplexInt: {
       llvm::Constant *Complex[2];
-      
-      Complex[0] = llvm::ConstantInt::get(Result.Val.getComplexIntReal());
-      Complex[1] = llvm::ConstantInt::get(Result.Val.getComplexIntImag());
-      
-      return llvm::ConstantStruct::get(Complex, 2);
+
+      Complex[0] = llvm::ConstantInt::get(VMContext,
+                                          Result.Val.getComplexIntReal());
+      Complex[1] = llvm::ConstantInt::get(VMContext,
+                                          Result.Val.getComplexIntImag());
+
+      // FIXME: the target may want to specify that this is packed.
+      return llvm::ConstantStruct::get(VMContext, Complex, 2, false);
     }
     case APValue::Float:
-      return llvm::ConstantFP::get(Result.Val.getFloat());
+      return llvm::ConstantFP::get(VMContext, Result.Val.getFloat());
     case APValue::ComplexFloat: {
       llvm::Constant *Complex[2];
-      
-      Complex[0] = llvm::ConstantFP::get(Result.Val.getComplexFloatReal());
-      Complex[1] = llvm::ConstantFP::get(Result.Val.getComplexFloatImag());
-      
-      return llvm::ConstantStruct::get(Complex, 2);
+
+      Complex[0] = llvm::ConstantFP::get(VMContext,
+                                         Result.Val.getComplexFloatReal());
+      Complex[1] = llvm::ConstantFP::get(VMContext,
+                                         Result.Val.getComplexFloatImag());
+
+      // FIXME: the target may want to specify that this is packed.
+      return llvm::ConstantStruct::get(VMContext, Complex, 2, false);
     }
     case APValue::Vector: {
       llvm::SmallVector<llvm::Constant *, 4> Inits;
       unsigned NumElts = Result.Val.getVectorLength();
-      
+
       for (unsigned i = 0; i != NumElts; ++i) {
         APValue &Elt = Result.Val.getVectorElt(i);
         if (Elt.isInt())
-          Inits.push_back(llvm::ConstantInt::get(Elt.getInt()));
+          Inits.push_back(llvm::ConstantInt::get(VMContext, Elt.getInt()));
         else
-          Inits.push_back(llvm::ConstantFP::get(Elt.getFloat()));
+          Inits.push_back(llvm::ConstantFP::get(VMContext, Elt.getFloat()));
       }
       return llvm::ConstantVector::get(&Inits[0], Inits.size());
     }
@@ -572,15 +915,58 @@ llvm::Constant *CodeGenModule::EmitConstantExpr(const Expr *E,
   }
 
   llvm::Constant* C = ConstExprEmitter(*this, CGF).Visit(const_cast<Expr*>(E));
-  if (C && C->getType() == llvm::Type::Int1Ty) {
+  if (C && C->getType() == llvm::Type::getInt1Ty(VMContext)) {
     const llvm::Type *BoolTy = getTypes().ConvertTypeForMem(E->getType());
     C = llvm::ConstantExpr::getZExt(C, BoolTy);
   }
   return C;
 }
 
+static inline bool isDataMemberPointerType(QualType T) {
+  if (const MemberPointerType *MPT = T->getAs<MemberPointerType>())
+    return !MPT->getPointeeType()->isFunctionType();
+  
+  return false;
+}
+
 llvm::Constant *CodeGenModule::EmitNullConstant(QualType T) {
-  // Always return an LLVM null constant for now; this will change when we
-  // get support for IRGen of member pointers.
-  return llvm::Constant::getNullValue(getTypes().ConvertType(T));
+  // No need to check for member pointers when not compiling C++.
+  if (!getContext().getLangOptions().CPlusPlus)
+    return llvm::Constant::getNullValue(getTypes().ConvertTypeForMem(T));
+
+  if (const ConstantArrayType *CAT = Context.getAsConstantArrayType(T)) {
+
+    QualType ElementTy = CAT->getElementType();
+
+    // FIXME: Handle arrays of structs that contain member pointers.
+    if (isDataMemberPointerType(Context.getBaseElementType(ElementTy))) {
+      llvm::Constant *Element = EmitNullConstant(ElementTy);
+      uint64_t NumElements = CAT->getSize().getZExtValue();
+      std::vector<llvm::Constant *> Array(NumElements);
+      for (uint64_t i = 0; i != NumElements; ++i)
+        Array[i] = Element;
+
+      const llvm::ArrayType *ATy =
+        cast<llvm::ArrayType>(getTypes().ConvertTypeForMem(T));
+      return llvm::ConstantArray::get(ATy, Array);
+    }
+  }
+
+  if (const RecordType *RT = T->getAs<RecordType>()) {
+    const RecordDecl *RD = RT->getDecl();
+    // FIXME: It would be better if there was a way to explicitly compute the
+    // record layout instead of converting to a type.
+    Types.ConvertTagDeclType(RD);
+
+    const CGRecordLayout &Layout = Types.getCGRecordLayout(RD);
+    if (Layout.containsMemberPointer()) {
+      assert(0 && "FIXME: No support for structs with member pointers yet!");
+    }
+  }
+
+  // FIXME: Handle structs that contain member pointers.
+  if (isDataMemberPointerType(T))
+    return llvm::Constant::getAllOnesValue(getTypes().ConvertTypeForMem(T));
+
+  return llvm::Constant::getNullValue(getTypes().ConvertTypeForMem(T));
 }