Add the clang library to the repo (with some of my changes, too).

1 files changed, 2201 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
new file mode 100644
index 0000000..82ee4fc
--- /dev/null
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -0,0 +1,2201 @@
+//===--- CGCall.cpp - Encapsulate calling convention details ----*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// These classes wrap the information about a call or function
+// definition used to handle ABI compliancy.
+//
+//===----------------------------------------------------------------------===//
+
+#include "CGCall.h"
+#include "CGCXXABI.h"
+#include "ABIInfo.h"
+#include "CodeGenFunction.h"
+#include "CodeGenModule.h"
+#include "TargetInfo.h"
+#include "clang/Basic/TargetInfo.h"
+#include "clang/AST/Decl.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/DeclObjC.h"
+#include "clang/Frontend/CodeGenOptions.h"
+#include "llvm/Attributes.h"
+#include "llvm/Support/CallSite.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/InlineAsm.h"
+#include "llvm/Transforms/Utils/Local.h"
+using namespace clang;
+using namespace CodeGen;
+
+/***/
+
+static unsigned ClangCallConvToLLVMCallConv(CallingConv CC) {
+  switch (CC) {
+  default: return llvm::CallingConv::C;
+  case CC_X86StdCall: return llvm::CallingConv::X86_StdCall;
+  case CC_X86FastCall: return llvm::CallingConv::X86_FastCall;
+  case CC_X86ThisCall: return llvm::CallingConv::X86_ThisCall;
+  case CC_AAPCS: return llvm::CallingConv::ARM_AAPCS;
+  case CC_AAPCS_VFP: return llvm::CallingConv::ARM_AAPCS_VFP;
+  // TODO: add support for CC_X86Pascal to llvm
+  }
+}
+
+/// Derives the 'this' type for codegen purposes, i.e. ignoring method
+/// qualification.
+/// FIXME: address space qualification?
+static CanQualType GetThisType(ASTContext &Context, const CXXRecordDecl *RD) {
+  QualType RecTy = Context.getTagDeclType(RD)->getCanonicalTypeInternal();
+  return Context.getPointerType(CanQualType::CreateUnsafe(RecTy));
+}
+
+/// Returns the canonical formal type of the given C++ method.
+static CanQual<FunctionProtoType> GetFormalType(const CXXMethodDecl *MD) {
+  return MD->getType()->getCanonicalTypeUnqualified()
+           .getAs<FunctionProtoType>();
+}
+
+/// Returns the "extra-canonicalized" return type, which discards
+/// qualifiers on the return type.  Codegen doesn't care about them,
+/// and it makes ABI code a little easier to be able to assume that
+/// all parameter and return types are top-level unqualified.
+static CanQualType GetReturnType(QualType RetTy) {
+  return RetTy->getCanonicalTypeUnqualified().getUnqualifiedType();
+}
+
+/// Arrange the argument and result information for a value of the
+/// given unprototyped function type.
+const CGFunctionInfo &
+CodeGenTypes::arrangeFunctionType(CanQual<FunctionNoProtoType> FTNP) {
+  // When translating an unprototyped function type, always use a
+  // variadic type.
+  return arrangeFunctionType(FTNP->getResultType().getUnqualifiedType(),
+                             ArrayRef<CanQualType>(),
+                             FTNP->getExtInfo(),
+                             RequiredArgs(0));
+}
+
+/// Arrange the argument and result information for a value of the
+/// given function type, on top of any implicit parameters already
+/// stored.
+static const CGFunctionInfo &arrangeFunctionType(CodeGenTypes &CGT,
+                                  SmallVectorImpl<CanQualType> &argTypes,
+                                             CanQual<FunctionProtoType> FTP) {
+  RequiredArgs required = RequiredArgs::forPrototypePlus(FTP, argTypes.size());
+  // FIXME: Kill copy.
+  for (unsigned i = 0, e = FTP->getNumArgs(); i != e; ++i)
+    argTypes.push_back(FTP->getArgType(i));
+  CanQualType resultType = FTP->getResultType().getUnqualifiedType();
+  return CGT.arrangeFunctionType(resultType, argTypes,
+                                 FTP->getExtInfo(), required);
+}
+
+/// Arrange the argument and result information for a value of the
+/// given function type.
+const CGFunctionInfo &
+CodeGenTypes::arrangeFunctionType(CanQual<FunctionProtoType> FTP) {
+  SmallVector<CanQualType, 16> argTypes;
+  return ::arrangeFunctionType(*this, argTypes, FTP);
+}
+
+static CallingConv getCallingConventionForDecl(const Decl *D) {
+  // Set the appropriate calling convention for the Function.
+  if (D->hasAttr<StdCallAttr>())
+    return CC_X86StdCall;
+
+  if (D->hasAttr<FastCallAttr>())
+    return CC_X86FastCall;
+
+  if (D->hasAttr<ThisCallAttr>())
+    return CC_X86ThisCall;
+
+  if (D->hasAttr<PascalAttr>())
+    return CC_X86Pascal;
+
+  if (PcsAttr *PCS = D->getAttr<PcsAttr>())
+    return (PCS->getPCS() == PcsAttr::AAPCS ? CC_AAPCS : CC_AAPCS_VFP);
+
+  return CC_C;
+}
+
+/// Arrange the argument and result information for a call to an
+/// unknown C++ non-static member function of the given abstract type.
+/// The member function must be an ordinary function, i.e. not a
+/// constructor or destructor.
+const CGFunctionInfo &
+CodeGenTypes::arrangeCXXMethodType(const CXXRecordDecl *RD,
+                                   const FunctionProtoType *FTP) {
+  SmallVector<CanQualType, 16> argTypes;
+
+  // Add the 'this' pointer.
+  argTypes.push_back(GetThisType(Context, RD));
+
+  return ::arrangeFunctionType(*this, argTypes,
+              FTP->getCanonicalTypeUnqualified().getAs<FunctionProtoType>());
+}
+
+/// Arrange the argument and result information for a declaration or
+/// definition of the given C++ non-static member function.  The
+/// member function must be an ordinary function, i.e. not a
+/// constructor or destructor.
+const CGFunctionInfo &
+CodeGenTypes::arrangeCXXMethodDeclaration(const CXXMethodDecl *MD) {
+  assert(!isa<CXXConstructorDecl>(MD) && "wrong method for contructors!");
+  assert(!isa<CXXDestructorDecl>(MD) && "wrong method for destructors!");
+
+  CanQual<FunctionProtoType> prototype = GetFormalType(MD);
+
+  if (MD->isInstance()) {
+    // The abstract case is perfectly fine.
+    return arrangeCXXMethodType(MD->getParent(), prototype.getTypePtr());
+  }
+
+  return arrangeFunctionType(prototype);
+}
+
+/// Arrange the argument and result information for a declaration
+/// or definition to the given constructor variant.
+const CGFunctionInfo &
+CodeGenTypes::arrangeCXXConstructorDeclaration(const CXXConstructorDecl *D,
+                                               CXXCtorType ctorKind) {
+  SmallVector<CanQualType, 16> argTypes;
+  argTypes.push_back(GetThisType(Context, D->getParent()));
+  CanQualType resultType = Context.VoidTy;
+
+  TheCXXABI.BuildConstructorSignature(D, ctorKind, resultType, argTypes);
+
+  CanQual<FunctionProtoType> FTP = GetFormalType(D);
+
+  RequiredArgs required = RequiredArgs::forPrototypePlus(FTP, argTypes.size());
+
+  // Add the formal parameters.
+  for (unsigned i = 0, e = FTP->getNumArgs(); i != e; ++i)
+    argTypes.push_back(FTP->getArgType(i));
+
+  return arrangeFunctionType(resultType, argTypes, FTP->getExtInfo(), required);
+}
+
+/// Arrange the argument and result information for a declaration,
+/// definition, or call to the given destructor variant.  It so
+/// happens that all three cases produce the same information.
+const CGFunctionInfo &
+CodeGenTypes::arrangeCXXDestructor(const CXXDestructorDecl *D,
+                                   CXXDtorType dtorKind) {
+  SmallVector<CanQualType, 2> argTypes;
+  argTypes.push_back(GetThisType(Context, D->getParent()));
+  CanQualType resultType = Context.VoidTy;
+
+  TheCXXABI.BuildDestructorSignature(D, dtorKind, resultType, argTypes);
+
+  CanQual<FunctionProtoType> FTP = GetFormalType(D);
+  assert(FTP->getNumArgs() == 0 && "dtor with formal parameters");
+
+  return arrangeFunctionType(resultType, argTypes, FTP->getExtInfo(),
+                             RequiredArgs::All);
+}
+
+/// Arrange the argument and result information for the declaration or
+/// definition of the given function.
+const CGFunctionInfo &
+CodeGenTypes::arrangeFunctionDeclaration(const FunctionDecl *FD) {
+  if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD))
+    if (MD->isInstance())
+      return arrangeCXXMethodDeclaration(MD);
+
+  CanQualType FTy = FD->getType()->getCanonicalTypeUnqualified();
+
+  assert(isa<FunctionType>(FTy));
+
+  // When declaring a function without a prototype, always use a
+  // non-variadic type.
+  if (isa<FunctionNoProtoType>(FTy)) {
+    CanQual<FunctionNoProtoType> noProto = FTy.getAs<FunctionNoProtoType>();
+    return arrangeFunctionType(noProto->getResultType(),
+                               ArrayRef<CanQualType>(),
+                               noProto->getExtInfo(),
+                               RequiredArgs::All);
+  }
+
+  assert(isa<FunctionProtoType>(FTy));
+  return arrangeFunctionType(FTy.getAs<FunctionProtoType>());
+}
+
+/// Arrange the argument and result information for the declaration or
+/// definition of an Objective-C method.
+const CGFunctionInfo &
+CodeGenTypes::arrangeObjCMethodDeclaration(const ObjCMethodDecl *MD) {
+  // It happens that this is the same as a call with no optional
+  // arguments, except also using the formal 'self' type.
+  return arrangeObjCMessageSendSignature(MD, MD->getSelfDecl()->getType());
+}
+
+/// Arrange the argument and result information for the function type
+/// through which to perform a send to the given Objective-C method,
+/// using the given receiver type.  The receiver type is not always
+/// the 'self' type of the method or even an Objective-C pointer type.
+/// This is *not* the right method for actually performing such a
+/// message send, due to the possibility of optional arguments.
+const CGFunctionInfo &
+CodeGenTypes::arrangeObjCMessageSendSignature(const ObjCMethodDecl *MD,
+                                              QualType receiverType) {
+  SmallVector<CanQualType, 16> argTys;
+  argTys.push_back(Context.getCanonicalParamType(receiverType));
+  argTys.push_back(Context.getCanonicalParamType(Context.getObjCSelType()));
+  // FIXME: Kill copy?
+  for (ObjCMethodDecl::param_const_iterator i = MD->param_begin(),
+         e = MD->param_end(); i != e; ++i) {
+    argTys.push_back(Context.getCanonicalParamType((*i)->getType()));
+  }
+
+  FunctionType::ExtInfo einfo;
+  einfo = einfo.withCallingConv(getCallingConventionForDecl(MD));
+
+  if (getContext().getLangOpts().ObjCAutoRefCount &&
+      MD->hasAttr<NSReturnsRetainedAttr>())
+    einfo = einfo.withProducesResult(true);
+
+  RequiredArgs required =
+    (MD->isVariadic() ? RequiredArgs(argTys.size()) : RequiredArgs::All);
+
+  return arrangeFunctionType(GetReturnType(MD->getResultType()), argTys,
+                             einfo, required);
+}
+
+const CGFunctionInfo &
+CodeGenTypes::arrangeGlobalDeclaration(GlobalDecl GD) {
+  // FIXME: Do we need to handle ObjCMethodDecl?
+  const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
+
+  if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD))
+    return arrangeCXXConstructorDeclaration(CD, GD.getCtorType());
+
+  if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(FD))
+    return arrangeCXXDestructor(DD, GD.getDtorType());
+
+  return arrangeFunctionDeclaration(FD);
+}
+
+/// Figure out the rules for calling a function with the given formal
+/// type using the given arguments.  The arguments are necessary
+/// because the function might be unprototyped, in which case it's
+/// target-dependent in crazy ways.
+const CGFunctionInfo &
+CodeGenTypes::arrangeFunctionCall(const CallArgList &args,
+                                  const FunctionType *fnType) {
+  RequiredArgs required = RequiredArgs::All;
+  if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fnType)) {
+    if (proto->isVariadic())
+      required = RequiredArgs(proto->getNumArgs());
+  } else if (CGM.getTargetCodeGenInfo()
+               .isNoProtoCallVariadic(args, cast<FunctionNoProtoType>(fnType))) {
+    required = RequiredArgs(0);
+  }
+
+  return arrangeFunctionCall(fnType->getResultType(), args,
+                             fnType->getExtInfo(), required);
+}
+
+const CGFunctionInfo &
+CodeGenTypes::arrangeFunctionCall(QualType resultType,
+                                  const CallArgList &args,
+                                  const FunctionType::ExtInfo &info,
+                                  RequiredArgs required) {
+  // FIXME: Kill copy.
+  SmallVector<CanQualType, 16> argTypes;
+  for (CallArgList::const_iterator i = args.begin(), e = args.end();
+       i != e; ++i)
+    argTypes.push_back(Context.getCanonicalParamType(i->Ty));
+  return arrangeFunctionType(GetReturnType(resultType), argTypes, info,
+                             required);
+}
+
+const CGFunctionInfo &
+CodeGenTypes::arrangeFunctionDeclaration(QualType resultType,
+                                         const FunctionArgList &args,
+                                         const FunctionType::ExtInfo &info,
+                                         bool isVariadic) {
+  // FIXME: Kill copy.
+  SmallVector<CanQualType, 16> argTypes;
+  for (FunctionArgList::const_iterator i = args.begin(), e = args.end();
+       i != e; ++i)
+    argTypes.push_back(Context.getCanonicalParamType((*i)->getType()));
+
+  RequiredArgs required =
+    (isVariadic ? RequiredArgs(args.size()) : RequiredArgs::All);
+  return arrangeFunctionType(GetReturnType(resultType), argTypes, info,
+                             required);
+}
+
+const CGFunctionInfo &CodeGenTypes::arrangeNullaryFunction() {
+  return arrangeFunctionType(getContext().VoidTy, ArrayRef<CanQualType>(),
+                             FunctionType::ExtInfo(), RequiredArgs::All);
+}
+
+/// Arrange the argument and result information for an abstract value
+/// of a given function type.  This is the method which all of the
+/// above functions ultimately defer to.
+const CGFunctionInfo &
+CodeGenTypes::arrangeFunctionType(CanQualType resultType,
+                                  ArrayRef<CanQualType> argTypes,
+                                  const FunctionType::ExtInfo &info,
+                                  RequiredArgs required) {
+#ifndef NDEBUG
+  for (ArrayRef<CanQualType>::const_iterator
+         I = argTypes.begin(), E = argTypes.end(); I != E; ++I)
+    assert(I->isCanonicalAsParam());
+#endif
+
+  unsigned CC = ClangCallConvToLLVMCallConv(info.getCC());
+
+  // Lookup or create unique function info.
+  llvm::FoldingSetNodeID ID;
+  CGFunctionInfo::Profile(ID, info, required, resultType, argTypes);
+
+  void *insertPos = 0;
+  CGFunctionInfo *FI = FunctionInfos.FindNodeOrInsertPos(ID, insertPos);
+  if (FI)
+    return *FI;
+
+  // Construct the function info.  We co-allocate the ArgInfos.
+  FI = CGFunctionInfo::create(CC, info, resultType, argTypes, required);
+  FunctionInfos.InsertNode(FI, insertPos);
+
+  bool inserted = FunctionsBeingProcessed.insert(FI); (void)inserted;
+  assert(inserted && "Recursively being processed?");
+  
+  // Compute ABI information.
+  getABIInfo().computeInfo(*FI);
+
+  // Loop over all of the computed argument and return value info.  If any of
+  // them are direct or extend without a specified coerce type, specify the
+  // default now.
+  ABIArgInfo &retInfo = FI->getReturnInfo();
+  if (retInfo.canHaveCoerceToType() && retInfo.getCoerceToType() == 0)
+    retInfo.setCoerceToType(ConvertType(FI->getReturnType()));
+
+  for (CGFunctionInfo::arg_iterator I = FI->arg_begin(), E = FI->arg_end();
+       I != E; ++I)
+    if (I->info.canHaveCoerceToType() && I->info.getCoerceToType() == 0)
+      I->info.setCoerceToType(ConvertType(I->type));
+
+  bool erased = FunctionsBeingProcessed.erase(FI); (void)erased;
+  assert(erased && "Not in set?");
+  
+  return *FI;
+}
+
+CGFunctionInfo *CGFunctionInfo::create(unsigned llvmCC,
+                                       const FunctionType::ExtInfo &info,
+                                       CanQualType resultType,
+                                       ArrayRef<CanQualType> argTypes,
+                                       RequiredArgs required) {
+  void *buffer = operator new(sizeof(CGFunctionInfo) +
+                              sizeof(ArgInfo) * (argTypes.size() + 1));
+  CGFunctionInfo *FI = new(buffer) CGFunctionInfo();
+  FI->CallingConvention = llvmCC;
+  FI->EffectiveCallingConvention = llvmCC;
+  FI->ASTCallingConvention = info.getCC();
+  FI->NoReturn = info.getNoReturn();
+  FI->ReturnsRetained = info.getProducesResult();
+  FI->Required = required;
+  FI->HasRegParm = info.getHasRegParm();
+  FI->RegParm = info.getRegParm();
+  FI->NumArgs = argTypes.size();
+  FI->getArgsBuffer()[0].type = resultType;
+  for (unsigned i = 0, e = argTypes.size(); i != e; ++i)
+    FI->getArgsBuffer()[i + 1].type = argTypes[i];
+  return FI;
+}
+
+/***/
+
+void CodeGenTypes::GetExpandedTypes(QualType type,
+                     SmallVectorImpl<llvm::Type*> &expandedTypes) {
+  if (const ConstantArrayType *AT = Context.getAsConstantArrayType(type)) {
+    uint64_t NumElts = AT->getSize().getZExtValue();
+    for (uint64_t Elt = 0; Elt < NumElts; ++Elt)
+      GetExpandedTypes(AT->getElementType(), expandedTypes);
+  } else if (const RecordType *RT = type->getAs<RecordType>()) {
+    const RecordDecl *RD = RT->getDecl();
+    assert(!RD->hasFlexibleArrayMember() &&
+           "Cannot expand structure with flexible array.");
+    if (RD->isUnion()) {
+      // Unions can be here only in degenerative cases - all the fields are same
+      // after flattening. Thus we have to use the "largest" field.
+      const FieldDecl *LargestFD = 0;
+      CharUnits UnionSize = CharUnits::Zero();
+
+      for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
+           i != e; ++i) {
+        const FieldDecl *FD = *i;
+        assert(!FD->isBitField() &&
+               "Cannot expand structure with bit-field members.");
+        CharUnits FieldSize = getContext().getTypeSizeInChars(FD->getType());
+        if (UnionSize < FieldSize) {
+          UnionSize = FieldSize;
+          LargestFD = FD;
+        }
+      }
+      if (LargestFD)
+        GetExpandedTypes(LargestFD->getType(), expandedTypes);
+    } else {
+      for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
+           i != e; ++i) {
+        const FieldDecl *FD = *i;
+        assert(!FD->isBitField() &&
+               "Cannot expand structure with bit-field members.");
+        GetExpandedTypes(FD->getType(), expandedTypes);
+      }
+    }
+  } else if (const ComplexType *CT = type->getAs<ComplexType>()) {
+    llvm::Type *EltTy = ConvertType(CT->getElementType());
+    expandedTypes.push_back(EltTy);
+    expandedTypes.push_back(EltTy);
+  } else
+    expandedTypes.push_back(ConvertType(type));
+}
+
+llvm::Function::arg_iterator
+CodeGenFunction::ExpandTypeFromArgs(QualType Ty, LValue LV,
+                                    llvm::Function::arg_iterator AI) {
+  assert(LV.isSimple() &&
+         "Unexpected non-simple lvalue during struct expansion.");
+
+  if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
+    unsigned NumElts = AT->getSize().getZExtValue();
+    QualType EltTy = AT->getElementType();
+    for (unsigned Elt = 0; Elt < NumElts; ++Elt) {
+      llvm::Value *EltAddr = Builder.CreateConstGEP2_32(LV.getAddress(), 0, Elt);
+      LValue LV = MakeAddrLValue(EltAddr, EltTy);
+      AI = ExpandTypeFromArgs(EltTy, LV, AI);
+    }
+  } else if (const RecordType *RT = Ty->getAs<RecordType>()) {
+    RecordDecl *RD = RT->getDecl();
+    if (RD->isUnion()) {
+      // Unions can be here only in degenerative cases - all the fields are same
+      // after flattening. Thus we have to use the "largest" field.
+      const FieldDecl *LargestFD = 0;
+      CharUnits UnionSize = CharUnits::Zero();
+
+      for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
+           i != e; ++i) {
+        const FieldDecl *FD = *i;
+        assert(!FD->isBitField() &&
+               "Cannot expand structure with bit-field members.");
+        CharUnits FieldSize = getContext().getTypeSizeInChars(FD->getType());
+        if (UnionSize < FieldSize) {
+          UnionSize = FieldSize;
+          LargestFD = FD;
+        }
+      }
+      if (LargestFD) {
+        // FIXME: What are the right qualifiers here?
+        LValue SubLV = EmitLValueForField(LV, LargestFD);
+        AI = ExpandTypeFromArgs(LargestFD->getType(), SubLV, AI);
+      }
+    } else {
+      for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
+           i != e; ++i) {
+        FieldDecl *FD = *i;
+        QualType FT = FD->getType();
+
+        // FIXME: What are the right qualifiers here?
+        LValue SubLV = EmitLValueForField(LV, FD);
+        AI = ExpandTypeFromArgs(FT, SubLV, AI);
+      }
+    }
+  } else if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
+    QualType EltTy = CT->getElementType();
+    llvm::Value *RealAddr = Builder.CreateStructGEP(LV.getAddress(), 0, "real");
+    EmitStoreThroughLValue(RValue::get(AI++), MakeAddrLValue(RealAddr, EltTy));
+    llvm::Value *ImagAddr = Builder.CreateStructGEP(LV.getAddress(), 1, "imag");
+    EmitStoreThroughLValue(RValue::get(AI++), MakeAddrLValue(ImagAddr, EltTy));
+  } else {
+    EmitStoreThroughLValue(RValue::get(AI), LV);
+    ++AI;
+  }
+
+  return AI;
+}
+
+/// EnterStructPointerForCoercedAccess - Given a struct pointer that we are
+/// accessing some number of bytes out of it, try to gep into the struct to get
+/// at its inner goodness.  Dive as deep as possible without entering an element
+/// with an in-memory size smaller than DstSize.
+static llvm::Value *
+EnterStructPointerForCoercedAccess(llvm::Value *SrcPtr,
+                                   llvm::StructType *SrcSTy,
+                                   uint64_t DstSize, CodeGenFunction &CGF) {
+  // We can't dive into a zero-element struct.
+  if (SrcSTy->getNumElements() == 0) return SrcPtr;
+
+  llvm::Type *FirstElt = SrcSTy->getElementType(0);
+
+  // If the first elt is at least as large as what we're looking for, or if the
+  // first element is the same size as the whole struct, we can enter it.
+  uint64_t FirstEltSize =
+    CGF.CGM.getTargetData().getTypeAllocSize(FirstElt);
+  if (FirstEltSize < DstSize &&
+      FirstEltSize < CGF.CGM.getTargetData().getTypeAllocSize(SrcSTy))
+    return SrcPtr;
+
+  // GEP into the first element.
+  SrcPtr = CGF.Builder.CreateConstGEP2_32(SrcPtr, 0, 0, "coerce.dive");
+
+  // If the first element is a struct, recurse.
+  llvm::Type *SrcTy =
+    cast<llvm::PointerType>(SrcPtr->getType())->getElementType();
+  if (llvm::StructType *SrcSTy = dyn_cast<llvm::StructType>(SrcTy))
+    return EnterStructPointerForCoercedAccess(SrcPtr, SrcSTy, DstSize, CGF);
+
+  return SrcPtr;
+}
+
+/// CoerceIntOrPtrToIntOrPtr - Convert a value Val to the specific Ty where both
+/// are either integers or pointers.  This does a truncation of the value if it
+/// is too large or a zero extension if it is too small.
+static llvm::Value *CoerceIntOrPtrToIntOrPtr(llvm::Value *Val,
+                                             llvm::Type *Ty,
+                                             CodeGenFunction &CGF) {
+  if (Val->getType() == Ty)
+    return Val;
+
+  if (isa<llvm::PointerType>(Val->getType())) {
+    // If this is Pointer->Pointer avoid conversion to and from int.
+    if (isa<llvm::PointerType>(Ty))
+      return CGF.Builder.CreateBitCast(Val, Ty, "coerce.val");
+
+    // Convert the pointer to an integer so we can play with its width.
+    Val = CGF.Builder.CreatePtrToInt(Val, CGF.IntPtrTy, "coerce.val.pi");
+  }
+
+  llvm::Type *DestIntTy = Ty;
+  if (isa<llvm::PointerType>(DestIntTy))
+    DestIntTy = CGF.IntPtrTy;
+
+  if (Val->getType() != DestIntTy)
+    Val = CGF.Builder.CreateIntCast(Val, DestIntTy, false, "coerce.val.ii");
+
+  if (isa<llvm::PointerType>(Ty))
+    Val = CGF.Builder.CreateIntToPtr(Val, Ty, "coerce.val.ip");
+  return Val;
+}
+
+
+
+/// CreateCoercedLoad - Create a load from \arg SrcPtr interpreted as
+/// a pointer to an object of type \arg Ty.
+///
+/// This safely handles the case when the src type is smaller than the
+/// destination type; in this situation the values of bits which not
+/// present in the src are undefined.
+static llvm::Value *CreateCoercedLoad(llvm::Value *SrcPtr,
+                                      llvm::Type *Ty,
+                                      CodeGenFunction &CGF) {
+  llvm::Type *SrcTy =
+    cast<llvm::PointerType>(SrcPtr->getType())->getElementType();
+
+  // If SrcTy and Ty are the same, just do a load.
+  if (SrcTy == Ty)
+    return CGF.Builder.CreateLoad(SrcPtr);
+
+  uint64_t DstSize = CGF.CGM.getTargetData().getTypeAllocSize(Ty);
+
+  if (llvm::StructType *SrcSTy = dyn_cast<llvm::StructType>(SrcTy)) {
+    SrcPtr = EnterStructPointerForCoercedAccess(SrcPtr, SrcSTy, DstSize, CGF);
+    SrcTy = cast<llvm::PointerType>(SrcPtr->getType())->getElementType();
+  }
+
+  uint64_t SrcSize = CGF.CGM.getTargetData().getTypeAllocSize(SrcTy);
+
+  // If the source and destination are integer or pointer types, just do an
+  // extension or truncation to the desired type.
+  if ((isa<llvm::IntegerType>(Ty) || isa<llvm::PointerType>(Ty)) &&
+      (isa<llvm::IntegerType>(SrcTy) || isa<llvm::PointerType>(SrcTy))) {
+    llvm::LoadInst *Load = CGF.Builder.CreateLoad(SrcPtr);
+    return CoerceIntOrPtrToIntOrPtr(Load, Ty, CGF);
+  }
+
+  // If load is legal, just bitcast the src pointer.
+  if (SrcSize >= DstSize) {
+    // Generally SrcSize is never greater than DstSize, since this means we are
+    // losing bits. However, this can happen in cases where the structure has
+    // additional padding, for example due to a user specified alignment.
+    //
+    // FIXME: Assert that we aren't truncating non-padding bits when have access
+    // to that information.
+    llvm::Value *Casted =
+      CGF.Builder.CreateBitCast(SrcPtr, llvm::PointerType::getUnqual(Ty));
+    llvm::LoadInst *Load = CGF.Builder.CreateLoad(Casted);
+    // FIXME: Use better alignment / avoid requiring aligned load.
+    Load->setAlignment(1);
+    return Load;
+  }
+
+  // Otherwise do coercion through memory. This is stupid, but
+  // simple.
+  llvm::Value *Tmp = CGF.CreateTempAlloca(Ty);
+  llvm::Value *Casted =
+    CGF.Builder.CreateBitCast(Tmp, llvm::PointerType::getUnqual(SrcTy));
+  llvm::StoreInst *Store =
+    CGF.Builder.CreateStore(CGF.Builder.CreateLoad(SrcPtr), Casted);
+  // FIXME: Use better alignment / avoid requiring aligned store.
+  Store->setAlignment(1);
+  return CGF.Builder.CreateLoad(Tmp);
+}
+
+// Function to store a first-class aggregate into memory.  We prefer to
+// store the elements rather than the aggregate to be more friendly to
+// fast-isel.
+// FIXME: Do we need to recurse here?
+static void BuildAggStore(CodeGenFunction &CGF, llvm::Value *Val,
+                          llvm::Value *DestPtr, bool DestIsVolatile,
+                          bool LowAlignment) {
+  // Prefer scalar stores to first-class aggregate stores.
+  if (llvm::StructType *STy =
+        dyn_cast<llvm::StructType>(Val->getType())) {
+    for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
+      llvm::Value *EltPtr = CGF.Builder.CreateConstGEP2_32(DestPtr, 0, i);
+      llvm::Value *Elt = CGF.Builder.CreateExtractValue(Val, i);
+      llvm::StoreInst *SI = CGF.Builder.CreateStore(Elt, EltPtr,
+                                                    DestIsVolatile);
+      if (LowAlignment)
+        SI->setAlignment(1);
+    }
+  } else {
+    llvm::StoreInst *SI = CGF.Builder.CreateStore(Val, DestPtr, DestIsVolatile);
+    if (LowAlignment)
+      SI->setAlignment(1);
+  }
+}
+
+/// CreateCoercedStore - Create a store to \arg DstPtr from \arg Src,
+/// where the source and destination may have different types.
+///
+/// This safely handles the case when the src type is larger than the
+/// destination type; the upper bits of the src will be lost.
+static void CreateCoercedStore(llvm::Value *Src,
+                               llvm::Value *DstPtr,
+                               bool DstIsVolatile,
+                               CodeGenFunction &CGF) {
+  llvm::Type *SrcTy = Src->getType();
+  llvm::Type *DstTy =
+    cast<llvm::PointerType>(DstPtr->getType())->getElementType();
+  if (SrcTy == DstTy) {
+    CGF.Builder.CreateStore(Src, DstPtr, DstIsVolatile);
+    return;
+  }
+
+  uint64_t SrcSize = CGF.CGM.getTargetData().getTypeAllocSize(SrcTy);
+
+  if (llvm::StructType *DstSTy = dyn_cast<llvm::StructType>(DstTy)) {
+    DstPtr = EnterStructPointerForCoercedAccess(DstPtr, DstSTy, SrcSize, CGF);
+    DstTy = cast<llvm::PointerType>(DstPtr->getType())->getElementType();
+  }
+
+  // If the source and destination are integer or pointer types, just do an
+  // extension or truncation to the desired type.
+  if ((isa<llvm::IntegerType>(SrcTy) || isa<llvm::PointerType>(SrcTy)) &&
+      (isa<llvm::IntegerType>(DstTy) || isa<llvm::PointerType>(DstTy))) {
+    Src = CoerceIntOrPtrToIntOrPtr(Src, DstTy, CGF);
+    CGF.Builder.CreateStore(Src, DstPtr, DstIsVolatile);
+    return;
+  }
+
+  uint64_t DstSize = CGF.CGM.getTargetData().getTypeAllocSize(DstTy);
+
+  // If store is legal, just bitcast the src pointer.
+  if (SrcSize <= DstSize) {
+    llvm::Value *Casted =
+      CGF.Builder.CreateBitCast(DstPtr, llvm::PointerType::getUnqual(SrcTy));
+    // FIXME: Use better alignment / avoid requiring aligned store.
+    BuildAggStore(CGF, Src, Casted, DstIsVolatile, true);
+  } else {
+    // Otherwise do coercion through memory. This is stupid, but
+    // simple.
+
+    // Generally SrcSize is never greater than DstSize, since this means we are
+    // losing bits. However, this can happen in cases where the structure has
+    // additional padding, for example due to a user specified alignment.
+    //
+    // FIXME: Assert that we aren't truncating non-padding bits when have access
+    // to that information.
+    llvm::Value *Tmp = CGF.CreateTempAlloca(SrcTy);
+    CGF.Builder.CreateStore(Src, Tmp);
+    llvm::Value *Casted =
+      CGF.Builder.CreateBitCast(Tmp, llvm::PointerType::getUnqual(DstTy));
+    llvm::LoadInst *Load = CGF.Builder.CreateLoad(Casted);
+    // FIXME: Use better alignment / avoid requiring aligned load.
+    Load->setAlignment(1);
+    CGF.Builder.CreateStore(Load, DstPtr, DstIsVolatile);
+  }
+}
+
+/***/
+
+bool CodeGenModule::ReturnTypeUsesSRet(const CGFunctionInfo &FI) {
+  return FI.getReturnInfo().isIndirect();
+}
+
+bool CodeGenModule::ReturnTypeUsesFPRet(QualType ResultType) {
+  if (const BuiltinType *BT = ResultType->getAs<BuiltinType>()) {
+    switch (BT->getKind()) {
+    default:
+      return false;
+    case BuiltinType::Float:
+      return getContext().getTargetInfo().useObjCFPRetForRealType(TargetInfo::Float);
+    case BuiltinType::Double:
+      return getContext().getTargetInfo().useObjCFPRetForRealType(TargetInfo::Double);
+    case BuiltinType::LongDouble:
+      return getContext().getTargetInfo().useObjCFPRetForRealType(
+        TargetInfo::LongDouble);
+    }
+  }
+
+  return false;
+}
+
+bool CodeGenModule::ReturnTypeUsesFP2Ret(QualType ResultType) {
+  if (const ComplexType *CT = ResultType->getAs<ComplexType>()) {
+    if (const BuiltinType *BT = CT->getElementType()->getAs<BuiltinType>()) {
+      if (BT->getKind() == BuiltinType::LongDouble)
+        return getContext().getTargetInfo().useObjCFP2RetForComplexLongDouble();
+    }
+  }
+
+  return false;
+}
+
+llvm::FunctionType *CodeGenTypes::GetFunctionType(GlobalDecl GD) {
+  const CGFunctionInfo &FI = arrangeGlobalDeclaration(GD);
+  return GetFunctionType(FI);
+}
+
+llvm::FunctionType *
+CodeGenTypes::GetFunctionType(const CGFunctionInfo &FI) {
+  
+  bool Inserted = FunctionsBeingProcessed.insert(&FI); (void)Inserted;
+  assert(Inserted && "Recursively being processed?");
+  
+  SmallVector<llvm::Type*, 8> argTypes;
+  llvm::Type *resultType = 0;
+
+  const ABIArgInfo &retAI = FI.getReturnInfo();
+  switch (retAI.getKind()) {
+  case ABIArgInfo::Expand:
+    llvm_unreachable("Invalid ABI kind for return argument");
+
+  case ABIArgInfo::Extend:
+  case ABIArgInfo::Direct:
+    resultType = retAI.getCoerceToType();
+    break;
+
+  case ABIArgInfo::Indirect: {
+    assert(!retAI.getIndirectAlign() && "Align unused on indirect return.");
+    resultType = llvm::Type::getVoidTy(getLLVMContext());
+
+    QualType ret = FI.getReturnType();
+    llvm::Type *ty = ConvertType(ret);
+    unsigned addressSpace = Context.getTargetAddressSpace(ret);
+    argTypes.push_back(llvm::PointerType::get(ty, addressSpace));
+    break;
+  }
+
+  case ABIArgInfo::Ignore:
+    resultType = llvm::Type::getVoidTy(getLLVMContext());
+    break;
+  }
+
+  for (CGFunctionInfo::const_arg_iterator it = FI.arg_begin(),
+         ie = FI.arg_end(); it != ie; ++it) {
+    const ABIArgInfo &argAI = it->info;
+
+    switch (argAI.getKind()) {
+    case ABIArgInfo::Ignore:
+      break;
+
+    case ABIArgInfo::Indirect: {
+      // indirect arguments are always on the stack, which is addr space #0.
+      llvm::Type *LTy = ConvertTypeForMem(it->type);
+      argTypes.push_back(LTy->getPointerTo());
+      break;
+    }
+
+    case ABIArgInfo::Extend:
+    case ABIArgInfo::Direct: {
+      // Insert a padding type to ensure proper alignment.
+      if (llvm::Type *PaddingType = argAI.getPaddingType())
+        argTypes.push_back(PaddingType);
+      // If the coerce-to type is a first class aggregate, flatten it.  Either
+      // way is semantically identical, but fast-isel and the optimizer
+      // generally likes scalar values better than FCAs.
+      llvm::Type *argType = argAI.getCoerceToType();
+      if (llvm::StructType *st = dyn_cast<llvm::StructType>(argType)) {
+        for (unsigned i = 0, e = st->getNumElements(); i != e; ++i)
+          argTypes.push_back(st->getElementType(i));
+      } else {
+        argTypes.push_back(argType);
+      }
+      break;
+    }
+
+    case ABIArgInfo::Expand:
+      GetExpandedTypes(it->type, argTypes);
+      break;
+    }
+  }
+
+  bool Erased = FunctionsBeingProcessed.erase(&FI); (void)Erased;
+  assert(Erased && "Not in set?");
+  
+  return llvm::FunctionType::get(resultType, argTypes, FI.isVariadic());
+}
+
+llvm::Type *CodeGenTypes::GetFunctionTypeForVTable(GlobalDecl GD) {
+  const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
+  const FunctionProtoType *FPT = MD->getType()->getAs<FunctionProtoType>();
+
+  if (!isFuncTypeConvertible(FPT))
+    return llvm::StructType::get(getLLVMContext());
+    
+  const CGFunctionInfo *Info;
+  if (isa<CXXDestructorDecl>(MD))
+    Info = &arrangeCXXDestructor(cast<CXXDestructorDecl>(MD), GD.getDtorType());
+  else
+    Info = &arrangeCXXMethodDeclaration(MD);
+  return GetFunctionType(*Info);
+}
+
+void CodeGenModule::ConstructAttributeList(const CGFunctionInfo &FI,
+                                           const Decl *TargetDecl,
+                                           AttributeListType &PAL,
+                                           unsigned &CallingConv) {
+  llvm::Attributes FuncAttrs;
+  llvm::Attributes RetAttrs;
+
+  CallingConv = FI.getEffectiveCallingConvention();
+
+  if (FI.isNoReturn())
+    FuncAttrs |= llvm::Attribute::NoReturn;
+
+  // FIXME: handle sseregparm someday...
+  if (TargetDecl) {
+    if (TargetDecl->hasAttr<ReturnsTwiceAttr>())
+      FuncAttrs |= llvm::Attribute::ReturnsTwice;
+    if (TargetDecl->hasAttr<NoThrowAttr>())
+      FuncAttrs |= llvm::Attribute::NoUnwind;
+    else if (const FunctionDecl *Fn = dyn_cast<FunctionDecl>(TargetDecl)) {
+      const FunctionProtoType *FPT = Fn->getType()->getAs<FunctionProtoType>();
+      if (FPT && FPT->isNothrow(getContext()))
+        FuncAttrs |= llvm::Attribute::NoUnwind;
+    }
+
+    if (TargetDecl->hasAttr<NoReturnAttr>())
+      FuncAttrs |= llvm::Attribute::NoReturn;
+
+    if (TargetDecl->hasAttr<ReturnsTwiceAttr>())
+      FuncAttrs |= llvm::Attribute::ReturnsTwice;
+
+    // 'const' and 'pure' attribute functions are also nounwind.
+    if (TargetDecl->hasAttr<ConstAttr>()) {
+      FuncAttrs |= llvm::Attribute::ReadNone;
+      FuncAttrs |= llvm::Attribute::NoUnwind;
+    } else if (TargetDecl->hasAttr<PureAttr>()) {
+      FuncAttrs |= llvm::Attribute::ReadOnly;
+      FuncAttrs |= llvm::Attribute::NoUnwind;
+    }
+    if (TargetDecl->hasAttr<MallocAttr>())
+      RetAttrs |= llvm::Attribute::NoAlias;
+  }
+
+  if (CodeGenOpts.OptimizeSize)
+    FuncAttrs |= llvm::Attribute::OptimizeForSize;
+  if (CodeGenOpts.DisableRedZone)
+    FuncAttrs |= llvm::Attribute::NoRedZone;
+  if (CodeGenOpts.NoImplicitFloat)
+    FuncAttrs |= llvm::Attribute::NoImplicitFloat;
+
+  QualType RetTy = FI.getReturnType();
+  unsigned Index = 1;
+  const ABIArgInfo &RetAI = FI.getReturnInfo();
+  switch (RetAI.getKind()) {
+  case ABIArgInfo::Extend:
+   if (RetTy->hasSignedIntegerRepresentation())
+     RetAttrs |= llvm::Attribute::SExt;
+   else if (RetTy->hasUnsignedIntegerRepresentation())
+     RetAttrs |= llvm::Attribute::ZExt;
+    break;
+  case ABIArgInfo::Direct:
+  case ABIArgInfo::Ignore:
+    break;
+
+  case ABIArgInfo::Indirect:
+    PAL.push_back(llvm::AttributeWithIndex::get(Index,
+                                                llvm::Attribute::StructRet));
+    ++Index;
+    // sret disables readnone and readonly
+    FuncAttrs &= ~(llvm::Attribute::ReadOnly |
+                   llvm::Attribute::ReadNone);
+    break;
+
+  case ABIArgInfo::Expand:
+    llvm_unreachable("Invalid ABI kind for return argument");
+  }
+
+  if (RetAttrs)
+    PAL.push_back(llvm::AttributeWithIndex::get(0, RetAttrs));
+
+  // FIXME: RegParm should be reduced in case of global register variable.
+  signed RegParm;
+  if (FI.getHasRegParm())
+    RegParm = FI.getRegParm();
+  else
+    RegParm = CodeGenOpts.NumRegisterParameters;
+
+  unsigned PointerWidth = getContext().getTargetInfo().getPointerWidth(0);
+  for (CGFunctionInfo::const_arg_iterator it = FI.arg_begin(),
+         ie = FI.arg_end(); it != ie; ++it) {
+    QualType ParamType = it->type;
+    const ABIArgInfo &AI = it->info;
+    llvm::Attributes Attrs;
+
+    // 'restrict' -> 'noalias' is done in EmitFunctionProlog when we
+    // have the corresponding parameter variable.  It doesn't make
+    // sense to do it here because parameters are so messed up.
+    switch (AI.getKind()) {
+    case ABIArgInfo::Extend:
+      if (ParamType->isSignedIntegerOrEnumerationType())
+        Attrs |= llvm::Attribute::SExt;
+      else if (ParamType->isUnsignedIntegerOrEnumerationType())
+        Attrs |= llvm::Attribute::ZExt;
+      // FALL THROUGH
+    case ABIArgInfo::Direct:
+      if (RegParm > 0 &&
+          (ParamType->isIntegerType() || ParamType->isPointerType() ||
+           ParamType->isReferenceType())) {
+        RegParm -=
+        (Context.getTypeSize(ParamType) + PointerWidth - 1) / PointerWidth;
+        if (RegParm >= 0)
+          Attrs |= llvm::Attribute::InReg;
+      }
+      // FIXME: handle sseregparm someday...
+
+      // Increment Index if there is padding.
+      Index += (AI.getPaddingType() != 0);
+
+      if (llvm::StructType *STy =
+            dyn_cast<llvm::StructType>(AI.getCoerceToType()))
+        Index += STy->getNumElements()-1;  // 1 will be added below.
+      break;
+
+    case ABIArgInfo::Indirect:
+      if (AI.getIndirectByVal())
+        Attrs |= llvm::Attribute::ByVal;
+
+      Attrs |=
+        llvm::Attribute::constructAlignmentFromInt(AI.getIndirectAlign());
+      // byval disables readnone and readonly.
+      FuncAttrs &= ~(llvm::Attribute::ReadOnly |
+                     llvm::Attribute::ReadNone);
+      break;
+
+    case ABIArgInfo::Ignore:
+      // Skip increment, no matching LLVM parameter.
+      continue;
+
+    case ABIArgInfo::Expand: {
+      SmallVector<llvm::Type*, 8> types;
+      // FIXME: This is rather inefficient. Do we ever actually need to do
+      // anything here? The result should be just reconstructed on the other
+      // side, so extension should be a non-issue.
+      getTypes().GetExpandedTypes(ParamType, types);
+      Index += types.size();
+      continue;
+    }
+    }
+
+    if (Attrs)
+      PAL.push_back(llvm::AttributeWithIndex::get(Index, Attrs));
+    ++Index;
+  }
+  if (FuncAttrs)
+    PAL.push_back(llvm::AttributeWithIndex::get(~0, FuncAttrs));
+}
+
+/// An argument came in as a promoted argument; demote it back to its
+/// declared type.
+static llvm::Value *emitArgumentDemotion(CodeGenFunction &CGF,
+                                         const VarDecl *var,
+                                         llvm::Value *value) {
+  llvm::Type *varType = CGF.ConvertType(var->getType());
+
+  // This can happen with promotions that actually don't change the
+  // underlying type, like the enum promotions.
+  if (value->getType() == varType) return value;
+
+  assert((varType->isIntegerTy() || varType->isFloatingPointTy())
+         && "unexpected promotion type");
+
+  if (isa<llvm::IntegerType>(varType))
+    return CGF.Builder.CreateTrunc(value, varType, "arg.unpromote");
+
+  return CGF.Builder.CreateFPCast(value, varType, "arg.unpromote");
+}
+
+void CodeGenFunction::EmitFunctionProlog(const CGFunctionInfo &FI,
+                                         llvm::Function *Fn,
+                                         const FunctionArgList &Args) {
+  // If this is an implicit-return-zero function, go ahead and
+  // initialize the return value.  TODO: it might be nice to have
+  // a more general mechanism for this that didn't require synthesized
+  // return statements.
+  if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(CurFuncDecl)) {
+    if (FD->hasImplicitReturnZero()) {
+      QualType RetTy = FD->getResultType().getUnqualifiedType();
+      llvm::Type* LLVMTy = CGM.getTypes().ConvertType(RetTy);
+      llvm::Constant* Zero = llvm::Constant::getNullValue(LLVMTy);
+      Builder.CreateStore(Zero, ReturnValue);
+    }
+  }
+
+  // FIXME: We no longer need the types from FunctionArgList; lift up and
+  // simplify.
+
+  // Emit allocs for param decls.  Give the LLVM Argument nodes names.
+  llvm::Function::arg_iterator AI = Fn->arg_begin();
+
+  // Name the struct return argument.
+  if (CGM.ReturnTypeUsesSRet(FI)) {
+    AI->setName("agg.result");
+    AI->addAttr(llvm::Attribute::NoAlias);
+    ++AI;
+  }
+
+  assert(FI.arg_size() == Args.size() &&
+         "Mismatch between function signature & arguments.");
+  unsigned ArgNo = 1;
+  CGFunctionInfo::const_arg_iterator info_it = FI.arg_begin();
+  for (FunctionArgList::const_iterator i = Args.begin(), e = Args.end(); 
+       i != e; ++i, ++info_it, ++ArgNo) {
+    const VarDecl *Arg = *i;
+    QualType Ty = info_it->type;
+    const ABIArgInfo &ArgI = info_it->info;
+
+    bool isPromoted =
+      isa<ParmVarDecl>(Arg) && cast<ParmVarDecl>(Arg)->isKNRPromoted();
+
+    switch (ArgI.getKind()) {
+    case ABIArgInfo::Indirect: {
+      llvm::Value *V = AI;
+
+      if (hasAggregateLLVMType(Ty)) {
+        // Aggregates and complex variables are accessed by reference.  All we
+        // need to do is realign the value, if requested
+        if (ArgI.getIndirectRealign()) {
+          llvm::Value *AlignedTemp = CreateMemTemp(Ty, "coerce");
+
+          // Copy from the incoming argument pointer to the temporary with the
+          // appropriate alignment.
+          //
+          // FIXME: We should have a common utility for generating an aggregate
+          // copy.
+          llvm::Type *I8PtrTy = Builder.getInt8PtrTy();
+          CharUnits Size = getContext().getTypeSizeInChars(Ty);
+          llvm::Value *Dst = Builder.CreateBitCast(AlignedTemp, I8PtrTy);
+          llvm::Value *Src = Builder.CreateBitCast(V, I8PtrTy);
+          Builder.CreateMemCpy(Dst,
+                               Src,
+                               llvm::ConstantInt::get(IntPtrTy, 
+                                                      Size.getQuantity()),
+                               ArgI.getIndirectAlign(),
+                               false);
+          V = AlignedTemp;
+        }
+      } else {
+        // Load scalar value from indirect argument.
+        CharUnits Alignment = getContext().getTypeAlignInChars(Ty);
+        V = EmitLoadOfScalar(V, false, Alignment.getQuantity(), Ty);
+
+        if (isPromoted)
+          V = emitArgumentDemotion(*this, Arg, V);
+      }
+      EmitParmDecl(*Arg, V, ArgNo);
+      break;
+    }
+
+    case ABIArgInfo::Extend:
+    case ABIArgInfo::Direct: {
+      // Skip the dummy padding argument.
+      if (ArgI.getPaddingType())
+        ++AI;
+
+      // If we have the trivial case, handle it with no muss and fuss.
+      if (!isa<llvm::StructType>(ArgI.getCoerceToType()) &&
+          ArgI.getCoerceToType() == ConvertType(Ty) &&
+          ArgI.getDirectOffset() == 0) {
+        assert(AI != Fn->arg_end() && "Argument mismatch!");
+        llvm::Value *V = AI;
+
+        if (Arg->getType().isRestrictQualified())
+          AI->addAttr(llvm::Attribute::NoAlias);
+
+        // Ensure the argument is the correct type.
+        if (V->getType() != ArgI.getCoerceToType())
+          V = Builder.CreateBitCast(V, ArgI.getCoerceToType());
+
+        if (isPromoted)
+          V = emitArgumentDemotion(*this, Arg, V);
+        
+        EmitParmDecl(*Arg, V, ArgNo);
+        break;
+      }
+
+      llvm::AllocaInst *Alloca = CreateMemTemp(Ty, Arg->getName());
+
+      // The alignment we need to use is the max of the requested alignment for
+      // the argument plus the alignment required by our access code below.
+      unsigned AlignmentToUse =
+        CGM.getTargetData().getABITypeAlignment(ArgI.getCoerceToType());
+      AlignmentToUse = std::max(AlignmentToUse,
+                        (unsigned)getContext().getDeclAlign(Arg).getQuantity());
+
+      Alloca->setAlignment(AlignmentToUse);
+      llvm::Value *V = Alloca;
+      llvm::Value *Ptr = V;    // Pointer to store into.
+
+      // If the value is offset in memory, apply the offset now.
+      if (unsigned Offs = ArgI.getDirectOffset()) {
+        Ptr = Builder.CreateBitCast(Ptr, Builder.getInt8PtrTy());
+        Ptr = Builder.CreateConstGEP1_32(Ptr, Offs);
+        Ptr = Builder.CreateBitCast(Ptr,
+                          llvm::PointerType::getUnqual(ArgI.getCoerceToType()));
+      }
+
+      // If the coerce-to type is a first class aggregate, we flatten it and
+      // pass the elements. Either way is semantically identical, but fast-isel
+      // and the optimizer generally likes scalar values better than FCAs.
+      llvm::StructType *STy = dyn_cast<llvm::StructType>(ArgI.getCoerceToType());
+      if (STy && STy->getNumElements() > 1) {
+        uint64_t SrcSize = CGM.getTargetData().getTypeAllocSize(STy);
+        llvm::Type *DstTy =
+          cast<llvm::PointerType>(Ptr->getType())->getElementType();
+        uint64_t DstSize = CGM.getTargetData().getTypeAllocSize(DstTy);
+
+        if (SrcSize <= DstSize) {
+          Ptr = Builder.CreateBitCast(Ptr, llvm::PointerType::getUnqual(STy));
+
+          for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
+            assert(AI != Fn->arg_end() && "Argument mismatch!");
+            AI->setName(Arg->getName() + ".coerce" + Twine(i));
+            llvm::Value *EltPtr = Builder.CreateConstGEP2_32(Ptr, 0, i);
+            Builder.CreateStore(AI++, EltPtr);
+          }
+        } else {
+          llvm::AllocaInst *TempAlloca =
+            CreateTempAlloca(ArgI.getCoerceToType(), "coerce");
+          TempAlloca->setAlignment(AlignmentToUse);
+          llvm::Value *TempV = TempAlloca;
+
+          for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
+            assert(AI != Fn->arg_end() && "Argument mismatch!");
+            AI->setName(Arg->getName() + ".coerce" + Twine(i));
+            llvm::Value *EltPtr = Builder.CreateConstGEP2_32(TempV, 0, i);
+            Builder.CreateStore(AI++, EltPtr);
+          }
+
+          Builder.CreateMemCpy(Ptr, TempV, DstSize, AlignmentToUse);
+        }
+      } else {
+        // Simple case, just do a coerced store of the argument into the alloca.
+        assert(AI != Fn->arg_end() && "Argument mismatch!");
+        AI->setName(Arg->getName() + ".coerce");
+        CreateCoercedStore(AI++, Ptr, /*DestIsVolatile=*/false, *this);
+      }
+
+
+      // Match to what EmitParmDecl is expecting for this type.
+      if (!CodeGenFunction::hasAggregateLLVMType(Ty)) {
+        V = EmitLoadOfScalar(V, false, AlignmentToUse, Ty);
+        if (isPromoted)
+          V = emitArgumentDemotion(*this, Arg, V);
+      }
+      EmitParmDecl(*Arg, V, ArgNo);
+      continue;  // Skip ++AI increment, already done.
+    }
+
+    case ABIArgInfo::Expand: {
+      // If this structure was expanded into multiple arguments then
+      // we need to create a temporary and reconstruct it from the
+      // arguments.
+      llvm::AllocaInst *Alloca = CreateMemTemp(Ty);
+      CharUnits Align = getContext().getDeclAlign(Arg);
+      Alloca->setAlignment(Align.getQuantity());
+      LValue LV = MakeAddrLValue(Alloca, Ty, Align);
+      llvm::Function::arg_iterator End = ExpandTypeFromArgs(Ty, LV, AI);
+      EmitParmDecl(*Arg, Alloca, ArgNo);
+
+      // Name the arguments used in expansion and increment AI.
+      unsigned Index = 0;
+      for (; AI != End; ++AI, ++Index)
+        AI->setName(Arg->getName() + "." + Twine(Index));
+      continue;
+    }
+
+    case ABIArgInfo::Ignore:
+      // Initialize the local variable appropriately.
+      if (hasAggregateLLVMType(Ty))
+        EmitParmDecl(*Arg, CreateMemTemp(Ty), ArgNo);
+      else
+        EmitParmDecl(*Arg, llvm::UndefValue::get(ConvertType(Arg->getType())),
+                     ArgNo);
+
+      // Skip increment, no matching LLVM parameter.
+      continue;
+    }
+
+    ++AI;
+  }
+  assert(AI == Fn->arg_end() && "Argument mismatch!");
+}
+
+static void eraseUnusedBitCasts(llvm::Instruction *insn) {
+  while (insn->use_empty()) {
+    llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(insn);
+    if (!bitcast) return;
+
+    // This is "safe" because we would have used a ConstantExpr otherwise.
+    insn = cast<llvm::Instruction>(bitcast->getOperand(0));
+    bitcast->eraseFromParent();
+  }
+}
+
+/// Try to emit a fused autorelease of a return result.
+static llvm::Value *tryEmitFusedAutoreleaseOfResult(CodeGenFunction &CGF,
+                                                    llvm::Value *result) {
+  // We must be immediately followed the cast.
+  llvm::BasicBlock *BB = CGF.Builder.GetInsertBlock();
+  if (BB->empty()) return 0;
+  if (&BB->back() != result) return 0;
+
+  llvm::Type *resultType = result->getType();
+
+  // result is in a BasicBlock and is therefore an Instruction.
+  llvm::Instruction *generator = cast<llvm::Instruction>(result);
+
+  SmallVector<llvm::Instruction*,4> insnsToKill;
+
+  // Look for:
+  //  %generator = bitcast %type1* %generator2 to %type2*
+  while (llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(generator)) {
+    // We would have emitted this as a constant if the operand weren't
+    // an Instruction.
+    generator = cast<llvm::Instruction>(bitcast->getOperand(0));
+
+    // Require the generator to be immediately followed by the cast.
+    if (generator->getNextNode() != bitcast)
+      return 0;
+
+    insnsToKill.push_back(bitcast);
+  }
+
+  // Look for:
+  //   %generator = call i8* @objc_retain(i8* %originalResult)
+  // or
+  //   %generator = call i8* @objc_retainAutoreleasedReturnValue(i8* %originalResult)
+  llvm::CallInst *call = dyn_cast<llvm::CallInst>(generator);
+  if (!call) return 0;
+
+  bool doRetainAutorelease;
+
+  if (call->getCalledValue() == CGF.CGM.getARCEntrypoints().objc_retain) {
+    doRetainAutorelease = true;
+  } else if (call->getCalledValue() == CGF.CGM.getARCEntrypoints()
+                                          .objc_retainAutoreleasedReturnValue) {
+    doRetainAutorelease = false;
+
+    // Look for an inline asm immediately preceding the call and kill it, too.
+    llvm::Instruction *prev = call->getPrevNode();
+    if (llvm::CallInst *asmCall = dyn_cast_or_null<llvm::CallInst>(prev))
+      if (asmCall->getCalledValue()
+            == CGF.CGM.getARCEntrypoints().retainAutoreleasedReturnValueMarker)
+        insnsToKill.push_back(prev);
+  } else {
+    return 0;
+  }
+
+  result = call->getArgOperand(0);
+  insnsToKill.push_back(call);
+
+  // Keep killing bitcasts, for sanity.  Note that we no longer care
+  // about precise ordering as long as there's exactly one use.
+  while (llvm::BitCastInst *bitcast = dyn_cast<llvm::BitCastInst>(result)) {
+    if (!bitcast->hasOneUse()) break;
+    insnsToKill.push_back(bitcast);
+    result = bitcast->getOperand(0);
+  }
+
+  // Delete all the unnecessary instructions, from latest to earliest.
+  for (SmallVectorImpl<llvm::Instruction*>::iterator
+         i = insnsToKill.begin(), e = insnsToKill.end(); i != e; ++i)
+    (*i)->eraseFromParent();
+
+  // Do the fused retain/autorelease if we were asked to.
+  if (doRetainAutorelease)
+    result = CGF.EmitARCRetainAutoreleaseReturnValue(result);
+
+  // Cast back to the result type.
+  return CGF.Builder.CreateBitCast(result, resultType);
+}
+
+/// If this is a +1 of the value of an immutable 'self', remove it.
+static llvm::Value *tryRemoveRetainOfSelf(CodeGenFunction &CGF,
+                                          llvm::Value *result) {
+  // This is only applicable to a method with an immutable 'self'.
+  const ObjCMethodDecl *method = dyn_cast<ObjCMethodDecl>(CGF.CurCodeDecl);
+  if (!method) return 0;
+  const VarDecl *self = method->getSelfDecl();
+  if (!self->getType().isConstQualified()) return 0;
+
+  // Look for a retain call.
+  llvm::CallInst *retainCall =
+    dyn_cast<llvm::CallInst>(result->stripPointerCasts());
+  if (!retainCall ||
+      retainCall->getCalledValue() != CGF.CGM.getARCEntrypoints().objc_retain)
+    return 0;
+
+  // Look for an ordinary load of 'self'.
+  llvm::Value *retainedValue = retainCall->getArgOperand(0);
+  llvm::LoadInst *load =
+    dyn_cast<llvm::LoadInst>(retainedValue->stripPointerCasts());
+  if (!load || load->isAtomic() || load->isVolatile() || 
+      load->getPointerOperand() != CGF.GetAddrOfLocalVar(self))
+    return 0;
+
+  // Okay!  Burn it all down.  This relies for correctness on the
+  // assumption that the retain is emitted as part of the return and
+  // that thereafter everything is used "linearly".
+  llvm::Type *resultType = result->getType();
+  eraseUnusedBitCasts(cast<llvm::Instruction>(result));
+  assert(retainCall->use_empty());
+  retainCall->eraseFromParent();
+  eraseUnusedBitCasts(cast<llvm::Instruction>(retainedValue));
+
+  return CGF.Builder.CreateBitCast(load, resultType);
+}
+
+/// Emit an ARC autorelease of the result of a function.
+///
+/// \return the value to actually return from the function
+static llvm::Value *emitAutoreleaseOfResult(CodeGenFunction &CGF,
+                                            llvm::Value *result) {
+  // If we're returning 'self', kill the initial retain.  This is a
+  // heuristic attempt to "encourage correctness" in the really unfortunate
+  // case where we have a return of self during a dealloc and we desperately
+  // need to avoid the possible autorelease.
+  if (llvm::Value *self = tryRemoveRetainOfSelf(CGF, result))
+    return self;
+
+  // At -O0, try to emit a fused retain/autorelease.
+  if (CGF.shouldUseFusedARCCalls())
+    if (llvm::Value *fused = tryEmitFusedAutoreleaseOfResult(CGF, result))
+      return fused;
+
+  return CGF.EmitARCAutoreleaseReturnValue(result);
+}
+
+/// Heuristically search for a dominating store to the return-value slot.
+static llvm::StoreInst *findDominatingStoreToReturnValue(CodeGenFunction &CGF) {
+  // If there are multiple uses of the return-value slot, just check
+  // for something immediately preceding the IP.  Sometimes this can
+  // happen with how we generate implicit-returns; it can also happen
+  // with noreturn cleanups.
+  if (!CGF.ReturnValue->hasOneUse()) {
+    llvm::BasicBlock *IP = CGF.Builder.GetInsertBlock();
+    if (IP->empty()) return 0;
+    llvm::StoreInst *store = dyn_cast<llvm::StoreInst>(&IP->back());
+    if (!store) return 0;
+    if (store->getPointerOperand() != CGF.ReturnValue) return 0;
+    assert(!store->isAtomic() && !store->isVolatile()); // see below
+    return store;
+  }
+
+  llvm::StoreInst *store =
+    dyn_cast<llvm::StoreInst>(CGF.ReturnValue->use_back());
+  if (!store) return 0;
+
+  // These aren't actually possible for non-coerced returns, and we
+  // only care about non-coerced returns on this code path.
+  assert(!store->isAtomic() && !store->isVolatile());
+
+  // Now do a first-and-dirty dominance check: just walk up the
+  // single-predecessors chain from the current insertion point.
+  llvm::BasicBlock *StoreBB = store->getParent();
+  llvm::BasicBlock *IP = CGF.Builder.GetInsertBlock();
+  while (IP != StoreBB) {
+    if (!(IP = IP->getSinglePredecessor()))
+      return 0;
+  }
+
+  // Okay, the store's basic block dominates the insertion point; we
+  // can do our thing.
+  return store;
+}
+
+void CodeGenFunction::EmitFunctionEpilog(const CGFunctionInfo &FI) {
+  // Functions with no result always return void.
+  if (ReturnValue == 0) {
+    Builder.CreateRetVoid();
+    return;
+  }
+
+  llvm::DebugLoc RetDbgLoc;
+  llvm::Value *RV = 0;
+  QualType RetTy = FI.getReturnType();
+  const ABIArgInfo &RetAI = FI.getReturnInfo();
+
+  switch (RetAI.getKind()) {
+  case ABIArgInfo::Indirect: {
+    unsigned Alignment = getContext().getTypeAlignInChars(RetTy).getQuantity();
+    if (RetTy->isAnyComplexType()) {
+      ComplexPairTy RT = LoadComplexFromAddr(ReturnValue, false);
+      StoreComplexToAddr(RT, CurFn->arg_begin(), false);
+    } else if (CodeGenFunction::hasAggregateLLVMType(RetTy)) {
+      // Do nothing; aggregrates get evaluated directly into the destination.
+    } else {
+      EmitStoreOfScalar(Builder.CreateLoad(ReturnValue), CurFn->arg_begin(),
+                        false, Alignment, RetTy);
+    }
+    break;
+  }
+
+  case ABIArgInfo::Extend:
+  case ABIArgInfo::Direct:
+    if (RetAI.getCoerceToType() == ConvertType(RetTy) &&
+        RetAI.getDirectOffset() == 0) {
+      // The internal return value temp always will have pointer-to-return-type
+      // type, just do a load.
+
+      // If there is a dominating store to ReturnValue, we can elide
+      // the load, zap the store, and usually zap the alloca.
+      if (llvm::StoreInst *SI = findDominatingStoreToReturnValue(*this)) {
+        // Get the stored value and nuke the now-dead store.
+        RetDbgLoc = SI->getDebugLoc();
+        RV = SI->getValueOperand();
+        SI->eraseFromParent();
+
+        // If that was the only use of the return value, nuke it as well now.
+        if (ReturnValue->use_empty() && isa<llvm::AllocaInst>(ReturnValue)) {
+          cast<llvm::AllocaInst>(ReturnValue)->eraseFromParent();
+          ReturnValue = 0;
+        }
+
+      // Otherwise, we have to do a simple load.
+      } else {
+        RV = Builder.CreateLoad(ReturnValue);
+      }
+    } else {
+      llvm::Value *V = ReturnValue;
+      // If the value is offset in memory, apply the offset now.
+      if (unsigned Offs = RetAI.getDirectOffset()) {
+        V = Builder.CreateBitCast(V, Builder.getInt8PtrTy());
+        V = Builder.CreateConstGEP1_32(V, Offs);
+        V = Builder.CreateBitCast(V,
+                         llvm::PointerType::getUnqual(RetAI.getCoerceToType()));
+      }
+
+      RV = CreateCoercedLoad(V, RetAI.getCoerceToType(), *this);
+    }
+
+    // In ARC, end functions that return a retainable type with a call
+    // to objc_autoreleaseReturnValue.
+    if (AutoreleaseResult) {
+      assert(getLangOpts().ObjCAutoRefCount &&
+             !FI.isReturnsRetained() &&
+             RetTy->isObjCRetainableType());
+      RV = emitAutoreleaseOfResult(*this, RV);
+    }
+
+    break;
+
+  case ABIArgInfo::Ignore:
+    break;
+
+  case ABIArgInfo::Expand:
+    llvm_unreachable("Invalid ABI kind for return argument");
+  }
+
+  llvm::Instruction *Ret = RV ? Builder.CreateRet(RV) : Builder.CreateRetVoid();
+  if (!RetDbgLoc.isUnknown())
+    Ret->setDebugLoc(RetDbgLoc);
+}
+
+void CodeGenFunction::EmitDelegateCallArg(CallArgList &args,
+                                          const VarDecl *param) {
+  // StartFunction converted the ABI-lowered parameter(s) into a
+  // local alloca.  We need to turn that into an r-value suitable
+  // for EmitCall.
+  llvm::Value *local = GetAddrOfLocalVar(param);
+
+  QualType type = param->getType();
+
+  // For the most part, we just need to load the alloca, except:
+  // 1) aggregate r-values are actually pointers to temporaries, and
+  // 2) references to aggregates are pointers directly to the aggregate.
+  // I don't know why references to non-aggregates are different here.
+  if (const ReferenceType *ref = type->getAs<ReferenceType>()) {
+    if (hasAggregateLLVMType(ref->getPointeeType()))
+      return args.add(RValue::getAggregate(local), type);
+
+    // Locals which are references to scalars are represented
+    // with allocas holding the pointer.
+    return args.add(RValue::get(Builder.CreateLoad(local)), type);
+  }
+
+  if (type->isAnyComplexType()) {
+    ComplexPairTy complex = LoadComplexFromAddr(local, /*volatile*/ false);
+    return args.add(RValue::getComplex(complex), type);
+  }
+
+  if (hasAggregateLLVMType(type))
+    return args.add(RValue::getAggregate(local), type);
+
+  unsigned alignment = getContext().getDeclAlign(param).getQuantity();
+  llvm::Value *value = EmitLoadOfScalar(local, false, alignment, type);
+  return args.add(RValue::get(value), type);
+}
+
+static bool isProvablyNull(llvm::Value *addr) {
+  return isa<llvm::ConstantPointerNull>(addr);
+}
+
+static bool isProvablyNonNull(llvm::Value *addr) {
+  return isa<llvm::AllocaInst>(addr);
+}
+
+/// Emit the actual writing-back of a writeback.
+static void emitWriteback(CodeGenFunction &CGF,
+                          const CallArgList::Writeback &writeback) {
+  llvm::Value *srcAddr = writeback.Address;
+  assert(!isProvablyNull(srcAddr) &&
+         "shouldn't have writeback for provably null argument");
+
+  llvm::BasicBlock *contBB = 0;
+
+  // If the argument wasn't provably non-null, we need to null check
+  // before doing the store.
+  bool provablyNonNull = isProvablyNonNull(srcAddr);
+  if (!provablyNonNull) {
+    llvm::BasicBlock *writebackBB = CGF.createBasicBlock("icr.writeback");
+    contBB = CGF.createBasicBlock("icr.done");
+
+    llvm::Value *isNull = CGF.Builder.CreateIsNull(srcAddr, "icr.isnull");
+    CGF.Builder.CreateCondBr(isNull, contBB, writebackBB);
+    CGF.EmitBlock(writebackBB);
+  }
+
+  // Load the value to writeback.
+  llvm::Value *value = CGF.Builder.CreateLoad(writeback.Temporary);
+
+  // Cast it back, in case we're writing an id to a Foo* or something.
+  value = CGF.Builder.CreateBitCast(value,
+               cast<llvm::PointerType>(srcAddr->getType())->getElementType(),
+                            "icr.writeback-cast");
+  
+  // Perform the writeback.
+  QualType srcAddrType = writeback.AddressType;
+  CGF.EmitStoreThroughLValue(RValue::get(value),
+                             CGF.MakeAddrLValue(srcAddr, srcAddrType));
+
+  // Jump to the continuation block.
+  if (!provablyNonNull)
+    CGF.EmitBlock(contBB);
+}
+
+static void emitWritebacks(CodeGenFunction &CGF,
+                           const CallArgList &args) {
+  for (CallArgList::writeback_iterator
+         i = args.writeback_begin(), e = args.writeback_end(); i != e; ++i)
+    emitWriteback(CGF, *i);
+}
+
+/// Emit an argument that's being passed call-by-writeback.  That is,
+/// we are passing the address of 
+static void emitWritebackArg(CodeGenFunction &CGF, CallArgList &args,
+                             const ObjCIndirectCopyRestoreExpr *CRE) {
+  llvm::Value *srcAddr = CGF.EmitScalarExpr(CRE->getSubExpr());
+
+  // The dest and src types don't necessarily match in LLVM terms
+  // because of the crazy ObjC compatibility rules.
+
+  llvm::PointerType *destType =
+    cast<llvm::PointerType>(CGF.ConvertType(CRE->getType()));
+
+  // If the address is a constant null, just pass the appropriate null.
+  if (isProvablyNull(srcAddr)) {
+    args.add(RValue::get(llvm::ConstantPointerNull::get(destType)),
+             CRE->getType());
+    return;
+  }
+
+  QualType srcAddrType =
+    CRE->getSubExpr()->getType()->castAs<PointerType>()->getPointeeType();
+
+  // Create the temporary.
+  llvm::Value *temp = CGF.CreateTempAlloca(destType->getElementType(),
+                                           "icr.temp");
+
+  // Zero-initialize it if we're not doing a copy-initialization.
+  bool shouldCopy = CRE->shouldCopy();
+  if (!shouldCopy) {
+    llvm::Value *null =
+      llvm::ConstantPointerNull::get(
+        cast<llvm::PointerType>(destType->getElementType()));
+    CGF.Builder.CreateStore(null, temp);
+  }
+
+  llvm::BasicBlock *contBB = 0;
+
+  // If the address is *not* known to be non-null, we need to switch.
+  llvm::Value *finalArgument;
+
+  bool provablyNonNull = isProvablyNonNull(srcAddr);
+  if (provablyNonNull) {
+    finalArgument = temp;
+  } else {
+    llvm::Value *isNull = CGF.Builder.CreateIsNull(srcAddr, "icr.isnull");
+
+    finalArgument = CGF.Builder.CreateSelect(isNull, 
+                                   llvm::ConstantPointerNull::get(destType),
+                                             temp, "icr.argument");
+
+    // If we need to copy, then the load has to be conditional, which
+    // means we need control flow.
+    if (shouldCopy) {
+      contBB = CGF.createBasicBlock("icr.cont");
+      llvm::BasicBlock *copyBB = CGF.createBasicBlock("icr.copy");
+      CGF.Builder.CreateCondBr(isNull, contBB, copyBB);
+      CGF.EmitBlock(copyBB);
+    }
+  }
+
+  // Perform a copy if necessary.
+  if (shouldCopy) {
+    LValue srcLV = CGF.MakeAddrLValue(srcAddr, srcAddrType);
+    RValue srcRV = CGF.EmitLoadOfLValue(srcLV);
+    assert(srcRV.isScalar());
+
+    llvm::Value *src = srcRV.getScalarVal();
+    src = CGF.Builder.CreateBitCast(src, destType->getElementType(),
+                                    "icr.cast");
+
+    // Use an ordinary store, not a store-to-lvalue.
+    CGF.Builder.CreateStore(src, temp);
+  }
+
+  // Finish the control flow if we needed it.
+  if (shouldCopy && !provablyNonNull)
+    CGF.EmitBlock(contBB);
+
+  args.addWriteback(srcAddr, srcAddrType, temp);
+  args.add(RValue::get(finalArgument), CRE->getType());
+}
+
+void CodeGenFunction::EmitCallArg(CallArgList &args, const Expr *E,
+                                  QualType type) {
+  if (const ObjCIndirectCopyRestoreExpr *CRE
+        = dyn_cast<ObjCIndirectCopyRestoreExpr>(E)) {
+    assert(getContext().getLangOpts().ObjCAutoRefCount);
+    assert(getContext().hasSameType(E->getType(), type));
+    return emitWritebackArg(*this, args, CRE);
+  }
+
+  assert(type->isReferenceType() == E->isGLValue() &&
+         "reference binding to unmaterialized r-value!");
+
+  if (E->isGLValue()) {
+    assert(E->getObjectKind() == OK_Ordinary);
+    return args.add(EmitReferenceBindingToExpr(E, /*InitializedDecl=*/0),
+                    type);
+  }
+
+  if (hasAggregateLLVMType(type) && !E->getType()->isAnyComplexType() &&
+      isa<ImplicitCastExpr>(E) &&
+      cast<CastExpr>(E)->getCastKind() == CK_LValueToRValue) {
+    LValue L = EmitLValue(cast<CastExpr>(E)->getSubExpr());
+    assert(L.isSimple());
+    args.add(L.asAggregateRValue(), type, /*NeedsCopy*/true);
+    return;
+  }
+
+  args.add(EmitAnyExprToTemp(E), type);
+}
+
+// In ObjC ARC mode with no ObjC ARC exception safety, tell the ARC
+// optimizer it can aggressively ignore unwind edges.
+void
+CodeGenFunction::AddObjCARCExceptionMetadata(llvm::Instruction *Inst) {
+  if (CGM.getCodeGenOpts().OptimizationLevel != 0 &&
+      !CGM.getCodeGenOpts().ObjCAutoRefCountExceptions)
+    Inst->setMetadata("clang.arc.no_objc_arc_exceptions",
+                      CGM.getNoObjCARCExceptionsMetadata());
+}
+
+/// Emits a call or invoke instruction to the given function, depending
+/// on the current state of the EH stack.
+llvm::CallSite
+CodeGenFunction::EmitCallOrInvoke(llvm::Value *Callee,
+                                  ArrayRef<llvm::Value *> Args,
+                                  const Twine &Name) {
+  llvm::BasicBlock *InvokeDest = getInvokeDest();
+
+  llvm::Instruction *Inst;
+  if (!InvokeDest)
+    Inst = Builder.CreateCall(Callee, Args, Name);
+  else {
+    llvm::BasicBlock *ContBB = createBasicBlock("invoke.cont");
+    Inst = Builder.CreateInvoke(Callee, ContBB, InvokeDest, Args, Name);
+    EmitBlock(ContBB);
+  }
+
+  // In ObjC ARC mode with no ObjC ARC exception safety, tell the ARC
+  // optimizer it can aggressively ignore unwind edges.
+  if (CGM.getLangOpts().ObjCAutoRefCount)
+    AddObjCARCExceptionMetadata(Inst);
+
+  return Inst;
+}
+
+llvm::CallSite
+CodeGenFunction::EmitCallOrInvoke(llvm::Value *Callee,
+                                  const Twine &Name) {
+  return EmitCallOrInvoke(Callee, ArrayRef<llvm::Value *>(), Name);
+}
+
+static void checkArgMatches(llvm::Value *Elt, unsigned &ArgNo,
+                            llvm::FunctionType *FTy) {
+  if (ArgNo < FTy->getNumParams())
+    assert(Elt->getType() == FTy->getParamType(ArgNo));
+  else
+    assert(FTy->isVarArg());
+  ++ArgNo;
+}
+
+void CodeGenFunction::ExpandTypeToArgs(QualType Ty, RValue RV,
+                                       SmallVector<llvm::Value*,16> &Args,
+                                       llvm::FunctionType *IRFuncTy) {
+  if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
+    unsigned NumElts = AT->getSize().getZExtValue();
+    QualType EltTy = AT->getElementType();
+    llvm::Value *Addr = RV.getAggregateAddr();
+    for (unsigned Elt = 0; Elt < NumElts; ++Elt) {
+      llvm::Value *EltAddr = Builder.CreateConstGEP2_32(Addr, 0, Elt);
+      LValue LV = MakeAddrLValue(EltAddr, EltTy);
+      RValue EltRV;
+      if (EltTy->isAnyComplexType())
+        // FIXME: Volatile?
+        EltRV = RValue::getComplex(LoadComplexFromAddr(LV.getAddress(), false));
+      else if (CodeGenFunction::hasAggregateLLVMType(EltTy))
+        EltRV = LV.asAggregateRValue();
+      else
+        EltRV = EmitLoadOfLValue(LV);
+      ExpandTypeToArgs(EltTy, EltRV, Args, IRFuncTy);
+    }
+  } else if (const RecordType *RT = Ty->getAs<RecordType>()) {
+    RecordDecl *RD = RT->getDecl();
+    assert(RV.isAggregate() && "Unexpected rvalue during struct expansion");
+    LValue LV = MakeAddrLValue(RV.getAggregateAddr(), Ty);
+
+    if (RD->isUnion()) {
+      const FieldDecl *LargestFD = 0;
+      CharUnits UnionSize = CharUnits::Zero();
+
+      for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
+           i != e; ++i) {
+        const FieldDecl *FD = *i;
+        assert(!FD->isBitField() &&
+               "Cannot expand structure with bit-field members.");
+        CharUnits FieldSize = getContext().getTypeSizeInChars(FD->getType());
+        if (UnionSize < FieldSize) {
+          UnionSize = FieldSize;
+          LargestFD = FD;
+        }
+      }
+      if (LargestFD) {
+        RValue FldRV = EmitRValueForField(LV, LargestFD);
+        ExpandTypeToArgs(LargestFD->getType(), FldRV, Args, IRFuncTy);
+      }
+    } else {
+      for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
+           i != e; ++i) {
+        FieldDecl *FD = *i;
+
+        RValue FldRV = EmitRValueForField(LV, FD);
+        ExpandTypeToArgs(FD->getType(), FldRV, Args, IRFuncTy);
+      }
+    }
+  } else if (Ty->isAnyComplexType()) {
+    ComplexPairTy CV = RV.getComplexVal();
+    Args.push_back(CV.first);
+    Args.push_back(CV.second);
+  } else {
+    assert(RV.isScalar() &&
+           "Unexpected non-scalar rvalue during struct expansion.");
+
+    // Insert a bitcast as needed.
+    llvm::Value *V = RV.getScalarVal();
+    if (Args.size() < IRFuncTy->getNumParams() &&
+        V->getType() != IRFuncTy->getParamType(Args.size()))
+      V = Builder.CreateBitCast(V, IRFuncTy->getParamType(Args.size()));
+
+    Args.push_back(V);
+  }
+}
+
+
+RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
+                                 llvm::Value *Callee,
+                                 ReturnValueSlot ReturnValue,
+                                 const CallArgList &CallArgs,
+                                 const Decl *TargetDecl,
+                                 llvm::Instruction **callOrInvoke) {
+  // FIXME: We no longer need the types from CallArgs; lift up and simplify.
+  SmallVector<llvm::Value*, 16> Args;
+
+  // Handle struct-return functions by passing a pointer to the
+  // location that we would like to return into.
+  QualType RetTy = CallInfo.getReturnType();
+  const ABIArgInfo &RetAI = CallInfo.getReturnInfo();
+
+  // IRArgNo - Keep track of the argument number in the callee we're looking at.
+  unsigned IRArgNo = 0;
+  llvm::FunctionType *IRFuncTy =
+    cast<llvm::FunctionType>(
+                  cast<llvm::PointerType>(Callee->getType())->getElementType());
+
+  // If the call returns a temporary with struct return, create a temporary
+  // alloca to hold the result, unless one is given to us.
+  if (CGM.ReturnTypeUsesSRet(CallInfo)) {
+    llvm::Value *Value = ReturnValue.getValue();
+    if (!Value)
+      Value = CreateMemTemp(RetTy);
+    Args.push_back(Value);
+    checkArgMatches(Value, IRArgNo, IRFuncTy);
+  }
+
+  assert(CallInfo.arg_size() == CallArgs.size() &&
+         "Mismatch between function signature & arguments.");
+  CGFunctionInfo::const_arg_iterator info_it = CallInfo.arg_begin();
+  for (CallArgList::const_iterator I = CallArgs.begin(), E = CallArgs.end();
+       I != E; ++I, ++info_it) {
+    const ABIArgInfo &ArgInfo = info_it->info;
+    RValue RV = I->RV;
+
+    unsigned TypeAlign =
+      getContext().getTypeAlignInChars(I->Ty).getQuantity();
+    switch (ArgInfo.getKind()) {
+    case ABIArgInfo::Indirect: {
+      if (RV.isScalar() || RV.isComplex()) {
+        // Make a temporary alloca to pass the argument.
+        llvm::AllocaInst *AI = CreateMemTemp(I->Ty);
+        if (ArgInfo.getIndirectAlign() > AI->getAlignment())
+          AI->setAlignment(ArgInfo.getIndirectAlign());
+        Args.push_back(AI);
+        
+        if (RV.isScalar())
+          EmitStoreOfScalar(RV.getScalarVal(), Args.back(), false,
+                            TypeAlign, I->Ty);
+        else
+          StoreComplexToAddr(RV.getComplexVal(), Args.back(), false);
+        
+        // Validate argument match.
+        checkArgMatches(AI, IRArgNo, IRFuncTy);
+      } else {
+        // We want to avoid creating an unnecessary temporary+copy here;
+        // however, we need one in two cases:
+        // 1. If the argument is not byval, and we are required to copy the
+        //    source.  (This case doesn't occur on any common architecture.)
+        // 2. If the argument is byval, RV is not sufficiently aligned, and
+        //    we cannot force it to be sufficiently aligned.
+        llvm::Value *Addr = RV.getAggregateAddr();
+        unsigned Align = ArgInfo.getIndirectAlign();
+        const llvm::TargetData *TD = &CGM.getTargetData();
+        if ((!ArgInfo.getIndirectByVal() && I->NeedsCopy) ||
+            (ArgInfo.getIndirectByVal() && TypeAlign < Align &&
+             llvm::getOrEnforceKnownAlignment(Addr, Align, TD) < Align)) {
+          // Create an aligned temporary, and copy to it.
+          llvm::AllocaInst *AI = CreateMemTemp(I->Ty);
+          if (Align > AI->getAlignment())
+            AI->setAlignment(Align);
+          Args.push_back(AI);
+          EmitAggregateCopy(AI, Addr, I->Ty, RV.isVolatileQualified());
+              
+          // Validate argument match.
+          checkArgMatches(AI, IRArgNo, IRFuncTy);
+        } else {
+          // Skip the extra memcpy call.
+          Args.push_back(Addr);
+          
+          // Validate argument match.
+          checkArgMatches(Addr, IRArgNo, IRFuncTy);
+        }
+      }
+      break;
+    }
+
+    case ABIArgInfo::Ignore:
+      break;
+
+    case ABIArgInfo::Extend:
+    case ABIArgInfo::Direct: {
+      // Insert a padding argument to ensure proper alignment.
+      if (llvm::Type *PaddingType = ArgInfo.getPaddingType()) {
+        Args.push_back(llvm::UndefValue::get(PaddingType));
+        ++IRArgNo;
+      }
+
+      if (!isa<llvm::StructType>(ArgInfo.getCoerceToType()) &&
+          ArgInfo.getCoerceToType() == ConvertType(info_it->type) &&
+          ArgInfo.getDirectOffset() == 0) {
+        llvm::Value *V;
+        if (RV.isScalar())
+          V = RV.getScalarVal();
+        else
+          V = Builder.CreateLoad(RV.getAggregateAddr());
+        
+        // If the argument doesn't match, perform a bitcast to coerce it.  This
+        // can happen due to trivial type mismatches.
+        if (IRArgNo < IRFuncTy->getNumParams() &&
+            V->getType() != IRFuncTy->getParamType(IRArgNo))
+          V = Builder.CreateBitCast(V, IRFuncTy->getParamType(IRArgNo));
+        Args.push_back(V);
+        
+        checkArgMatches(V, IRArgNo, IRFuncTy);
+        break;
+      }
+
+      // FIXME: Avoid the conversion through memory if possible.
+      llvm::Value *SrcPtr;
+      if (RV.isScalar()) {
+        SrcPtr = CreateMemTemp(I->Ty, "coerce");
+        EmitStoreOfScalar(RV.getScalarVal(), SrcPtr, false, TypeAlign, I->Ty);
+      } else if (RV.isComplex()) {
+        SrcPtr = CreateMemTemp(I->Ty, "coerce");
+        StoreComplexToAddr(RV.getComplexVal(), SrcPtr, false);
+      } else
+        SrcPtr = RV.getAggregateAddr();
+
+      // If the value is offset in memory, apply the offset now.
+      if (unsigned Offs = ArgInfo.getDirectOffset()) {
+        SrcPtr = Builder.CreateBitCast(SrcPtr, Builder.getInt8PtrTy());
+        SrcPtr = Builder.CreateConstGEP1_32(SrcPtr, Offs);
+        SrcPtr = Builder.CreateBitCast(SrcPtr,
+                       llvm::PointerType::getUnqual(ArgInfo.getCoerceToType()));
+
+      }
+
+      // If the coerce-to type is a first class aggregate, we flatten it and
+      // pass the elements. Either way is semantically identical, but fast-isel
+      // and the optimizer generally likes scalar values better than FCAs.
+      if (llvm::StructType *STy =
+            dyn_cast<llvm::StructType>(ArgInfo.getCoerceToType())) {
+        SrcPtr = Builder.CreateBitCast(SrcPtr,
+                                       llvm::PointerType::getUnqual(STy));
+        for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
+          llvm::Value *EltPtr = Builder.CreateConstGEP2_32(SrcPtr, 0, i);
+          llvm::LoadInst *LI = Builder.CreateLoad(EltPtr);
+          // We don't know what we're loading from.
+          LI->setAlignment(1);
+          Args.push_back(LI);
+          
+          // Validate argument match.
+          checkArgMatches(LI, IRArgNo, IRFuncTy);
+        }
+      } else {
+        // In the simple case, just pass the coerced loaded value.
+        Args.push_back(CreateCoercedLoad(SrcPtr, ArgInfo.getCoerceToType(),
+                                         *this));
+        
+        // Validate argument match.
+        checkArgMatches(Args.back(), IRArgNo, IRFuncTy);
+      }
+
+      break;
+    }
+
+    case ABIArgInfo::Expand:
+      ExpandTypeToArgs(I->Ty, RV, Args, IRFuncTy);
+      IRArgNo = Args.size();
+      break;
+    }
+  }
+
+  // If the callee is a bitcast of a function to a varargs pointer to function
+  // type, check to see if we can remove the bitcast.  This handles some cases
+  // with unprototyped functions.
+  if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Callee))
+    if (llvm::Function *CalleeF = dyn_cast<llvm::Function>(CE->getOperand(0))) {
+      llvm::PointerType *CurPT=cast<llvm::PointerType>(Callee->getType());
+      llvm::FunctionType *CurFT =
+        cast<llvm::FunctionType>(CurPT->getElementType());
+      llvm::FunctionType *ActualFT = CalleeF->getFunctionType();
+
+      if (CE->getOpcode() == llvm::Instruction::BitCast &&
+          ActualFT->getReturnType() == CurFT->getReturnType() &&
+          ActualFT->getNumParams() == CurFT->getNumParams() &&
+          ActualFT->getNumParams() == Args.size() &&
+          (CurFT->isVarArg() || !ActualFT->isVarArg())) {
+        bool ArgsMatch = true;
+        for (unsigned i = 0, e = ActualFT->getNumParams(); i != e; ++i)
+          if (ActualFT->getParamType(i) != CurFT->getParamType(i)) {
+            ArgsMatch = false;
+            break;
+          }
+
+        // Strip the cast if we can get away with it.  This is a nice cleanup,
+        // but also allows us to inline the function at -O0 if it is marked
+        // always_inline.
+        if (ArgsMatch)
+          Callee = CalleeF;
+      }
+    }
+
+  unsigned CallingConv;
+  CodeGen::AttributeListType AttributeList;
+  CGM.ConstructAttributeList(CallInfo, TargetDecl, AttributeList, CallingConv);
+  llvm::AttrListPtr Attrs = llvm::AttrListPtr::get(AttributeList.begin(),
+                                                   AttributeList.end());
+
+  llvm::BasicBlock *InvokeDest = 0;
+  if (!(Attrs.getFnAttributes() & llvm::Attribute::NoUnwind))
+    InvokeDest = getInvokeDest();
+
+  llvm::CallSite CS;
+  if (!InvokeDest) {
+    CS = Builder.CreateCall(Callee, Args);
+  } else {
+    llvm::BasicBlock *Cont = createBasicBlock("invoke.cont");
+    CS = Builder.CreateInvoke(Callee, Cont, InvokeDest, Args);
+    EmitBlock(Cont);
+  }
+  if (callOrInvoke)
+    *callOrInvoke = CS.getInstruction();
+
+  CS.setAttributes(Attrs);
+  CS.setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv));
+
+  // In ObjC ARC mode with no ObjC ARC exception safety, tell the ARC
+  // optimizer it can aggressively ignore unwind edges.
+  if (CGM.getLangOpts().ObjCAutoRefCount)
+    AddObjCARCExceptionMetadata(CS.getInstruction());
+
+  // If the call doesn't return, finish the basic block and clear the
+  // insertion point; this allows the rest of IRgen to discard
+  // unreachable code.
+  if (CS.doesNotReturn()) {
+    Builder.CreateUnreachable();
+    Builder.ClearInsertionPoint();
+
+    // FIXME: For now, emit a dummy basic block because expr emitters in
+    // generally are not ready to handle emitting expressions at unreachable
+    // points.
+    EnsureInsertPoint();
+
+    // Return a reasonable RValue.
+    return GetUndefRValue(RetTy);
+  }
+
+  llvm::Instruction *CI = CS.getInstruction();
+  if (Builder.isNamePreserving() && !CI->getType()->isVoidTy())
+    CI->setName("call");
+
+  // Emit any writebacks immediately.  Arguably this should happen
+  // after any return-value munging.
+  if (CallArgs.hasWritebacks())
+    emitWritebacks(*this, CallArgs);
+
+  switch (RetAI.getKind()) {
+  case ABIArgInfo::Indirect: {
+    unsigned Alignment = getContext().getTypeAlignInChars(RetTy).getQuantity();
+    if (RetTy->isAnyComplexType())
+      return RValue::getComplex(LoadComplexFromAddr(Args[0], false));
+    if (CodeGenFunction::hasAggregateLLVMType(RetTy))
+      return RValue::getAggregate(Args[0]);
+    return RValue::get(EmitLoadOfScalar(Args[0], false, Alignment, RetTy));
+  }
+
+  case ABIArgInfo::Ignore:
+    // If we are ignoring an argument that had a result, make sure to
+    // construct the appropriate return value for our caller.
+    return GetUndefRValue(RetTy);
+
+  case ABIArgInfo::Extend:
+  case ABIArgInfo::Direct: {
+    llvm::Type *RetIRTy = ConvertType(RetTy);
+    if (RetAI.getCoerceToType() == RetIRTy && RetAI.getDirectOffset() == 0) {
+      if (RetTy->isAnyComplexType()) {
+        llvm::Value *Real = Builder.CreateExtractValue(CI, 0);
+        llvm::Value *Imag = Builder.CreateExtractValue(CI, 1);
+        return RValue::getComplex(std::make_pair(Real, Imag));
+      }
+      if (CodeGenFunction::hasAggregateLLVMType(RetTy)) {
+        llvm::Value *DestPtr = ReturnValue.getValue();
+        bool DestIsVolatile = ReturnValue.isVolatile();
+
+        if (!DestPtr) {
+          DestPtr = CreateMemTemp(RetTy, "agg.tmp");
+          DestIsVolatile = false;
+        }
+        BuildAggStore(*this, CI, DestPtr, DestIsVolatile, false);
+        return RValue::getAggregate(DestPtr);
+      }
+      
+      // If the argument doesn't match, perform a bitcast to coerce it.  This
+      // can happen due to trivial type mismatches.
+      llvm::Value *V = CI;
+      if (V->getType() != RetIRTy)
+        V = Builder.CreateBitCast(V, RetIRTy);
+      return RValue::get(V);
+    }
+
+    llvm::Value *DestPtr = ReturnValue.getValue();
+    bool DestIsVolatile = ReturnValue.isVolatile();
+
+    if (!DestPtr) {
+      DestPtr = CreateMemTemp(RetTy, "coerce");
+      DestIsVolatile = false;
+    }
+
+    // If the value is offset in memory, apply the offset now.
+    llvm::Value *StorePtr = DestPtr;
+    if (unsigned Offs = RetAI.getDirectOffset()) {
+      StorePtr = Builder.CreateBitCast(StorePtr, Builder.getInt8PtrTy());
+      StorePtr = Builder.CreateConstGEP1_32(StorePtr, Offs);
+      StorePtr = Builder.CreateBitCast(StorePtr,
+                         llvm::PointerType::getUnqual(RetAI.getCoerceToType()));
+    }
+    CreateCoercedStore(CI, StorePtr, DestIsVolatile, *this);
+
+    unsigned Alignment = getContext().getTypeAlignInChars(RetTy).getQuantity();
+    if (RetTy->isAnyComplexType())
+      return RValue::getComplex(LoadComplexFromAddr(DestPtr, false));
+    if (CodeGenFunction::hasAggregateLLVMType(RetTy))
+      return RValue::getAggregate(DestPtr);
+    return RValue::get(EmitLoadOfScalar(DestPtr, false, Alignment, RetTy));
+  }
+
+  case ABIArgInfo::Expand:
+    llvm_unreachable("Invalid ABI kind for return argument");
+  }
+
+  llvm_unreachable("Unhandled ABIArgInfo::Kind");
+}
+
+/* VarArg handling */
+
+llvm::Value *CodeGenFunction::EmitVAArg(llvm::Value *VAListAddr, QualType Ty) {
+  return CGM.getTypes().getABIInfo().EmitVAArg(VAListAddr, Ty, *this);
+}