CGExpr.cpp revision 79bfb4b564dc3636aae15aafa6340f9430881121 
1//===--- CGExpr.cpp - Emit LLVM Code from Expressions ---------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This contains code to emit Expr nodes as LLVM code.
11//
12//===----------------------------------------------------------------------===//
13
14#include "CodeGenFunction.h"
15#include "CodeGenModule.h"
16#include "CGCall.h"
17#include "CGCXXABI.h"
18#include "CGDebugInfo.h"
19#include "CGRecordLayout.h"
20#include "CGObjCRuntime.h"
21#include "clang/AST/ASTContext.h"
22#include "clang/AST/DeclObjC.h"
23#include "llvm/Intrinsics.h"
24#include "clang/Frontend/CodeGenOptions.h"
25#include "llvm/Target/TargetData.h"
26using namespace clang;
27using namespace CodeGen;
28
29//===--------------------------------------------------------------------===//
30//                        Miscellaneous Helper Methods
31//===--------------------------------------------------------------------===//
32
33llvm::Value *CodeGenFunction::EmitCastToVoidPtr(llvm::Value *value) {
34  unsigned addressSpace =
35    cast<llvm::PointerType>(value->getType())->getAddressSpace();
36
37  const llvm::PointerType *destType = Int8PtrTy;
38  if (addressSpace)
39    destType = llvm::Type::getInt8PtrTy(getLLVMContext(), addressSpace);
40
41  if (value->getType() == destType) return value;
42  return Builder.CreateBitCast(value, destType);
43}
44
45/// CreateTempAlloca - This creates a alloca and inserts it into the entry
46/// block.
47llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(const llvm::Type *Ty,
48                                                    const llvm::Twine &Name) {
49  if (!Builder.isNamePreserving())
50    return new llvm::AllocaInst(Ty, 0, "", AllocaInsertPt);
51  return new llvm::AllocaInst(Ty, 0, Name, AllocaInsertPt);
52}
53
54void CodeGenFunction::InitTempAlloca(llvm::AllocaInst *Var,
55                                     llvm::Value *Init) {
56  llvm::StoreInst *Store = new llvm::StoreInst(Init, Var);
57  llvm::BasicBlock *Block = AllocaInsertPt->getParent();
58  Block->getInstList().insertAfter(&*AllocaInsertPt, Store);
59}
60
61llvm::AllocaInst *CodeGenFunction::CreateIRTemp(QualType Ty,
62                                                const llvm::Twine &Name) {
63  llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertType(Ty), Name);
64  // FIXME: Should we prefer the preferred type alignment here?
65  CharUnits Align = getContext().getTypeAlignInChars(Ty);
66  Alloc->setAlignment(Align.getQuantity());
67  return Alloc;
68}
69
70llvm::AllocaInst *CodeGenFunction::CreateMemTemp(QualType Ty,
71                                                 const llvm::Twine &Name) {
72  llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertTypeForMem(Ty), Name);
73  // FIXME: Should we prefer the preferred type alignment here?
74  CharUnits Align = getContext().getTypeAlignInChars(Ty);
75  Alloc->setAlignment(Align.getQuantity());
76  return Alloc;
77}
78
79/// EvaluateExprAsBool - Perform the usual unary conversions on the specified
80/// expression and compare the result against zero, returning an Int1Ty value.
81llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
82  if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) {
83    llvm::Value *MemPtr = EmitScalarExpr(E);
84    return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT);
85  }
86
87  QualType BoolTy = getContext().BoolTy;
88  if (!E->getType()->isAnyComplexType())
89    return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy);
90
91  return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(),BoolTy);
92}
93
94/// EmitIgnoredExpr - Emit code to compute the specified expression,
95/// ignoring the result.
96void CodeGenFunction::EmitIgnoredExpr(const Expr *E) {
97  if (E->isRValue())
98    return (void) EmitAnyExpr(E, AggValueSlot::ignored(), true);
99
100  // Just emit it as an l-value and drop the result.
101  EmitLValue(E);
102}
103
104/// EmitAnyExpr - Emit code to compute the specified expression which
105/// can have any type.  The result is returned as an RValue struct.
106/// If this is an aggregate expression, AggSlot indicates where the
107/// result should be returned.
108RValue CodeGenFunction::EmitAnyExpr(const Expr *E, AggValueSlot AggSlot,
109                                    bool IgnoreResult) {
110  if (!hasAggregateLLVMType(E->getType()))
111    return RValue::get(EmitScalarExpr(E, IgnoreResult));
112  else if (E->getType()->isAnyComplexType())
113    return RValue::getComplex(EmitComplexExpr(E, IgnoreResult, IgnoreResult));
114
115  EmitAggExpr(E, AggSlot, IgnoreResult);
116  return AggSlot.asRValue();
117}
118
119/// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will
120/// always be accessible even if no aggregate location is provided.
121RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) {
122  AggValueSlot AggSlot = AggValueSlot::ignored();
123
124  if (hasAggregateLLVMType(E->getType()) &&
125      !E->getType()->isAnyComplexType())
126    AggSlot = CreateAggTemp(E->getType(), "agg.tmp");
127  return EmitAnyExpr(E, AggSlot);
128}
129
130/// EmitAnyExprToMem - Evaluate an expression into a given memory
131/// location.
132void CodeGenFunction::EmitAnyExprToMem(const Expr *E,
133                                       llvm::Value *Location,
134                                       bool IsLocationVolatile,
135                                       bool IsInit) {
136  if (E->getType()->isComplexType())
137    EmitComplexExprIntoAddr(E, Location, IsLocationVolatile);
138  else if (hasAggregateLLVMType(E->getType()))
139    EmitAggExpr(E, AggValueSlot::forAddr(Location, IsLocationVolatile, IsInit));
140  else {
141    RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false));
142    LValue LV = MakeAddrLValue(Location, E->getType());
143    EmitStoreThroughLValue(RV, LV, E->getType());
144  }
145}
146
147namespace {
148/// \brief An adjustment to be made to the temporary created when emitting a
149/// reference binding, which accesses a particular subobject of that temporary.
150  struct SubobjectAdjustment {
151    enum { DerivedToBaseAdjustment, FieldAdjustment } Kind;
152
153    union {
154      struct {
155        const CastExpr *BasePath;
156        const CXXRecordDecl *DerivedClass;
157      } DerivedToBase;
158
159      FieldDecl *Field;
160    };
161
162    SubobjectAdjustment(const CastExpr *BasePath,
163                        const CXXRecordDecl *DerivedClass)
164      : Kind(DerivedToBaseAdjustment) {
165      DerivedToBase.BasePath = BasePath;
166      DerivedToBase.DerivedClass = DerivedClass;
167    }
168
169    SubobjectAdjustment(FieldDecl *Field)
170      : Kind(FieldAdjustment) {
171      this->Field = Field;
172    }
173  };
174}
175
176static llvm::Value *
177CreateReferenceTemporary(CodeGenFunction& CGF, QualType Type,
178                         const NamedDecl *InitializedDecl) {
179  if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(InitializedDecl)) {
180    if (VD->hasGlobalStorage()) {
181      llvm::SmallString<256> Name;
182      llvm::raw_svector_ostream Out(Name);
183      CGF.CGM.getCXXABI().getMangleContext().mangleReferenceTemporary(VD, Out);
184      Out.flush();
185
186      const llvm::Type *RefTempTy = CGF.ConvertTypeForMem(Type);
187
188      // Create the reference temporary.
189      llvm::GlobalValue *RefTemp =
190        new llvm::GlobalVariable(CGF.CGM.getModule(),
191                                 RefTempTy, /*isConstant=*/false,
192                                 llvm::GlobalValue::InternalLinkage,
193                                 llvm::Constant::getNullValue(RefTempTy),
194                                 Name.str());
195      return RefTemp;
196    }
197  }
198
199  return CGF.CreateMemTemp(Type, "ref.tmp");
200}
201
202static llvm::Value *
203EmitExprForReferenceBinding(CodeGenFunction &CGF, const Expr *E,
204                            llvm::Value *&ReferenceTemporary,
205                            const CXXDestructorDecl *&ReferenceTemporaryDtor,
206                            const NamedDecl *InitializedDecl) {
207  if (const CXXDefaultArgExpr *DAE = dyn_cast<CXXDefaultArgExpr>(E))
208    E = DAE->getExpr();
209
210  if (const ExprWithCleanups *TE = dyn_cast<ExprWithCleanups>(E)) {
211    CodeGenFunction::RunCleanupsScope Scope(CGF);
212
213    return EmitExprForReferenceBinding(CGF, TE->getSubExpr(),
214                                       ReferenceTemporary,
215                                       ReferenceTemporaryDtor,
216                                       InitializedDecl);
217  }
218
219  RValue RV;
220  if (E->isGLValue()) {
221    // Emit the expression as an lvalue.
222    LValue LV = CGF.EmitLValue(E);
223    if (LV.isSimple())
224      return LV.getAddress();
225
226    // We have to load the lvalue.
227    RV = CGF.EmitLoadOfLValue(LV, E->getType());
228  } else {
229    QualType ResultTy = E->getType();
230
231    llvm::SmallVector<SubobjectAdjustment, 2> Adjustments;
232    while (true) {
233      if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
234        E = PE->getSubExpr();
235        continue;
236      }
237
238      if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
239        if ((CE->getCastKind() == CK_DerivedToBase ||
240             CE->getCastKind() == CK_UncheckedDerivedToBase) &&
241            E->getType()->isRecordType()) {
242          E = CE->getSubExpr();
243          CXXRecordDecl *Derived
244            = cast<CXXRecordDecl>(E->getType()->getAs<RecordType>()->getDecl());
245          Adjustments.push_back(SubobjectAdjustment(CE, Derived));
246          continue;
247        }
248
249        if (CE->getCastKind() == CK_NoOp) {
250          E = CE->getSubExpr();
251          continue;
252        }
253      } else if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
254        if (!ME->isArrow() && ME->getBase()->isRValue()) {
255          assert(ME->getBase()->getType()->isRecordType());
256          if (FieldDecl *Field = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
257            E = ME->getBase();
258            Adjustments.push_back(SubobjectAdjustment(Field));
259            continue;
260          }
261        }
262      }
263
264      if (const OpaqueValueExpr *opaque = dyn_cast<OpaqueValueExpr>(E))
265        if (opaque->getType()->isRecordType())
266          return CGF.EmitOpaqueValueLValue(opaque).getAddress();
267
268      // Nothing changed.
269      break;
270    }
271
272    // Create a reference temporary if necessary.
273    AggValueSlot AggSlot = AggValueSlot::ignored();
274    if (CGF.hasAggregateLLVMType(E->getType()) &&
275        !E->getType()->isAnyComplexType()) {
276      ReferenceTemporary = CreateReferenceTemporary(CGF, E->getType(),
277                                                    InitializedDecl);
278      AggSlot = AggValueSlot::forAddr(ReferenceTemporary, false,
279                                      InitializedDecl != 0);
280    }
281
282    RV = CGF.EmitAnyExpr(E, AggSlot);
283
284    if (InitializedDecl) {
285      // Get the destructor for the reference temporary.
286      if (const RecordType *RT = E->getType()->getAs<RecordType>()) {
287        CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
288        if (!ClassDecl->hasTrivialDestructor())
289          ReferenceTemporaryDtor = ClassDecl->getDestructor();
290      }
291    }
292
293    // Check if need to perform derived-to-base casts and/or field accesses, to
294    // get from the temporary object we created (and, potentially, for which we
295    // extended the lifetime) to the subobject we're binding the reference to.
296    if (!Adjustments.empty()) {
297      llvm::Value *Object = RV.getAggregateAddr();
298      for (unsigned I = Adjustments.size(); I != 0; --I) {
299        SubobjectAdjustment &Adjustment = Adjustments[I-1];
300        switch (Adjustment.Kind) {
301        case SubobjectAdjustment::DerivedToBaseAdjustment:
302          Object =
303              CGF.GetAddressOfBaseClass(Object,
304                                        Adjustment.DerivedToBase.DerivedClass,
305                              Adjustment.DerivedToBase.BasePath->path_begin(),
306                              Adjustment.DerivedToBase.BasePath->path_end(),
307                                        /*NullCheckValue=*/false);
308          break;
309
310        case SubobjectAdjustment::FieldAdjustment: {
311          LValue LV =
312            CGF.EmitLValueForField(Object, Adjustment.Field, 0);
313          if (LV.isSimple()) {
314            Object = LV.getAddress();
315            break;
316          }
317
318          // For non-simple lvalues, we actually have to create a copy of
319          // the object we're binding to.
320          QualType T = Adjustment.Field->getType().getNonReferenceType()
321                                                  .getUnqualifiedType();
322          Object = CreateReferenceTemporary(CGF, T, InitializedDecl);
323          LValue TempLV = CGF.MakeAddrLValue(Object,
324                                             Adjustment.Field->getType());
325          CGF.EmitStoreThroughLValue(CGF.EmitLoadOfLValue(LV, T), TempLV, T);
326          break;
327        }
328
329        }
330      }
331
332      const llvm::Type *ResultPtrTy = CGF.ConvertType(ResultTy)->getPointerTo();
333      return CGF.Builder.CreateBitCast(Object, ResultPtrTy, "temp");
334    }
335  }
336
337  if (RV.isAggregate())
338    return RV.getAggregateAddr();
339
340  // Create a temporary variable that we can bind the reference to.
341  ReferenceTemporary = CreateReferenceTemporary(CGF, E->getType(),
342                                                InitializedDecl);
343
344
345  unsigned Alignment =
346    CGF.getContext().getTypeAlignInChars(E->getType()).getQuantity();
347  if (RV.isScalar())
348    CGF.EmitStoreOfScalar(RV.getScalarVal(), ReferenceTemporary,
349                          /*Volatile=*/false, Alignment, E->getType());
350  else
351    CGF.StoreComplexToAddr(RV.getComplexVal(), ReferenceTemporary,
352                           /*Volatile=*/false);
353  return ReferenceTemporary;
354}
355
356RValue
357CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E,
358                                            const NamedDecl *InitializedDecl) {
359  llvm::Value *ReferenceTemporary = 0;
360  const CXXDestructorDecl *ReferenceTemporaryDtor = 0;
361  llvm::Value *Value = EmitExprForReferenceBinding(*this, E, ReferenceTemporary,
362                                                   ReferenceTemporaryDtor,
363                                                   InitializedDecl);
364  if (!ReferenceTemporaryDtor)
365    return RValue::get(Value);
366
367  // Make sure to call the destructor for the reference temporary.
368  if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(InitializedDecl)) {
369    if (VD->hasGlobalStorage()) {
370      llvm::Constant *DtorFn =
371        CGM.GetAddrOfCXXDestructor(ReferenceTemporaryDtor, Dtor_Complete);
372      EmitCXXGlobalDtorRegistration(DtorFn,
373                                    cast<llvm::Constant>(ReferenceTemporary));
374
375      return RValue::get(Value);
376    }
377  }
378
379  PushDestructorCleanup(ReferenceTemporaryDtor, ReferenceTemporary);
380
381  return RValue::get(Value);
382}
383
384
385/// getAccessedFieldNo - Given an encoded value and a result number, return the
386/// input field number being accessed.
387unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
388                                             const llvm::Constant *Elts) {
389  if (isa<llvm::ConstantAggregateZero>(Elts))
390    return 0;
391
392  return cast<llvm::ConstantInt>(Elts->getOperand(Idx))->getZExtValue();
393}
394
395void CodeGenFunction::EmitCheck(llvm::Value *Address, unsigned Size) {
396  if (!CatchUndefined)
397    return;
398
399  // This needs to be to the standard address space.
400  Address = Builder.CreateBitCast(Address, Int8PtrTy);
401
402  const llvm::Type *IntPtrT = IntPtrTy;
403  llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, &IntPtrT, 1);
404
405  // In time, people may want to control this and use a 1 here.
406  llvm::Value *Arg = Builder.getFalse();
407  llvm::Value *C = Builder.CreateCall2(F, Address, Arg);
408  llvm::BasicBlock *Cont = createBasicBlock();
409  llvm::BasicBlock *Check = createBasicBlock();
410  llvm::Value *NegativeOne = llvm::ConstantInt::get(IntPtrTy, -1ULL);
411  Builder.CreateCondBr(Builder.CreateICmpEQ(C, NegativeOne), Cont, Check);
412
413  EmitBlock(Check);
414  Builder.CreateCondBr(Builder.CreateICmpUGE(C,
415                                        llvm::ConstantInt::get(IntPtrTy, Size)),
416                       Cont, getTrapBB());
417  EmitBlock(Cont);
418}
419
420
421CodeGenFunction::ComplexPairTy CodeGenFunction::
422EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
423                         bool isInc, bool isPre) {
424  ComplexPairTy InVal = LoadComplexFromAddr(LV.getAddress(),
425                                            LV.isVolatileQualified());
426
427  llvm::Value *NextVal;
428  if (isa<llvm::IntegerType>(InVal.first->getType())) {
429    uint64_t AmountVal = isInc ? 1 : -1;
430    NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
431
432    // Add the inc/dec to the real part.
433    NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
434  } else {
435    QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
436    llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
437    if (!isInc)
438      FVal.changeSign();
439    NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
440
441    // Add the inc/dec to the real part.
442    NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
443  }
444
445  ComplexPairTy IncVal(NextVal, InVal.second);
446
447  // Store the updated result through the lvalue.
448  StoreComplexToAddr(IncVal, LV.getAddress(), LV.isVolatileQualified());
449
450  // If this is a postinc, return the value read from memory, otherwise use the
451  // updated value.
452  return isPre ? IncVal : InVal;
453}
454
455
456//===----------------------------------------------------------------------===//
457//                         LValue Expression Emission
458//===----------------------------------------------------------------------===//
459
460RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
461  if (Ty->isVoidType())
462    return RValue::get(0);
463
464  if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
465    const llvm::Type *EltTy = ConvertType(CTy->getElementType());
466    llvm::Value *U = llvm::UndefValue::get(EltTy);
467    return RValue::getComplex(std::make_pair(U, U));
468  }
469
470  // If this is a use of an undefined aggregate type, the aggregate must have an
471  // identifiable address.  Just because the contents of the value are undefined
472  // doesn't mean that the address can't be taken and compared.
473  if (hasAggregateLLVMType(Ty)) {
474    llvm::Value *DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
475    return RValue::getAggregate(DestPtr);
476  }
477
478  return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
479}
480
481RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
482                                              const char *Name) {
483  ErrorUnsupported(E, Name);
484  return GetUndefRValue(E->getType());
485}
486
487LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
488                                              const char *Name) {
489  ErrorUnsupported(E, Name);
490  llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
491  return MakeAddrLValue(llvm::UndefValue::get(Ty), E->getType());
492}
493
494LValue CodeGenFunction::EmitCheckedLValue(const Expr *E) {
495  LValue LV = EmitLValue(E);
496  if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple())
497    EmitCheck(LV.getAddress(),
498              getContext().getTypeSizeInChars(E->getType()).getQuantity());
499  return LV;
500}
501
502/// EmitLValue - Emit code to compute a designator that specifies the location
503/// of the expression.
504///
505/// This can return one of two things: a simple address or a bitfield reference.
506/// In either case, the LLVM Value* in the LValue structure is guaranteed to be
507/// an LLVM pointer type.
508///
509/// If this returns a bitfield reference, nothing about the pointee type of the
510/// LLVM value is known: For example, it may not be a pointer to an integer.
511///
512/// If this returns a normal address, and if the lvalue's C type is fixed size,
513/// this method guarantees that the returned pointer type will point to an LLVM
514/// type of the same size of the lvalue's type.  If the lvalue has a variable
515/// length type, this is not possible.
516///
517LValue CodeGenFunction::EmitLValue(const Expr *E) {
518  switch (E->getStmtClass()) {
519  default: return EmitUnsupportedLValue(E, "l-value expression");
520
521  case Expr::ObjCSelectorExprClass:
522  return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
523  case Expr::ObjCIsaExprClass:
524    return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
525  case Expr::BinaryOperatorClass:
526    return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
527  case Expr::CompoundAssignOperatorClass:
528    if (!E->getType()->isAnyComplexType())
529      return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
530    return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
531  case Expr::CallExprClass:
532  case Expr::CXXMemberCallExprClass:
533  case Expr::CXXOperatorCallExprClass:
534    return EmitCallExprLValue(cast<CallExpr>(E));
535  case Expr::VAArgExprClass:
536    return EmitVAArgExprLValue(cast<VAArgExpr>(E));
537  case Expr::DeclRefExprClass:
538    return EmitDeclRefLValue(cast<DeclRefExpr>(E));
539  case Expr::ParenExprClass:return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
540  case Expr::PredefinedExprClass:
541    return EmitPredefinedLValue(cast<PredefinedExpr>(E));
542  case Expr::StringLiteralClass:
543    return EmitStringLiteralLValue(cast<StringLiteral>(E));
544  case Expr::ObjCEncodeExprClass:
545    return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
546
547  case Expr::BlockDeclRefExprClass:
548    return EmitBlockDeclRefLValue(cast<BlockDeclRefExpr>(E));
549
550  case Expr::CXXTemporaryObjectExprClass:
551  case Expr::CXXConstructExprClass:
552    return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
553  case Expr::CXXBindTemporaryExprClass:
554    return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
555  case Expr::ExprWithCleanupsClass:
556    return EmitExprWithCleanupsLValue(cast<ExprWithCleanups>(E));
557  case Expr::CXXScalarValueInitExprClass:
558    return EmitNullInitializationLValue(cast<CXXScalarValueInitExpr>(E));
559  case Expr::CXXDefaultArgExprClass:
560    return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr());
561  case Expr::CXXTypeidExprClass:
562    return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
563
564  case Expr::ObjCMessageExprClass:
565    return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
566  case Expr::ObjCIvarRefExprClass:
567    return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
568  case Expr::ObjCPropertyRefExprClass:
569    return EmitObjCPropertyRefLValue(cast<ObjCPropertyRefExpr>(E));
570  case Expr::StmtExprClass:
571    return EmitStmtExprLValue(cast<StmtExpr>(E));
572  case Expr::UnaryOperatorClass:
573    return EmitUnaryOpLValue(cast<UnaryOperator>(E));
574  case Expr::ArraySubscriptExprClass:
575    return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
576  case Expr::ExtVectorElementExprClass:
577    return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
578  case Expr::MemberExprClass:
579    return EmitMemberExpr(cast<MemberExpr>(E));
580  case Expr::CompoundLiteralExprClass:
581    return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
582  case Expr::ConditionalOperatorClass:
583    return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
584  case Expr::BinaryConditionalOperatorClass:
585    return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
586  case Expr::ChooseExprClass:
587    return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(getContext()));
588  case Expr::OpaqueValueExprClass:
589    return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
590  case Expr::ImplicitCastExprClass:
591  case Expr::CStyleCastExprClass:
592  case Expr::CXXFunctionalCastExprClass:
593  case Expr::CXXStaticCastExprClass:
594  case Expr::CXXDynamicCastExprClass:
595  case Expr::CXXReinterpretCastExprClass:
596  case Expr::CXXConstCastExprClass:
597    return EmitCastLValue(cast<CastExpr>(E));
598  }
599}
600
601llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile,
602                                              unsigned Alignment, QualType Ty,
603                                              llvm::MDNode *TBAAInfo) {
604  llvm::LoadInst *Load = Builder.CreateLoad(Addr, "tmp");
605  if (Volatile)
606    Load->setVolatile(true);
607  if (Alignment)
608    Load->setAlignment(Alignment);
609  if (TBAAInfo)
610    CGM.DecorateInstruction(Load, TBAAInfo);
611
612  return EmitFromMemory(Load, Ty);
613}
614
615static bool isBooleanUnderlyingType(QualType Ty) {
616  if (const EnumType *ET = dyn_cast<EnumType>(Ty))
617    return ET->getDecl()->getIntegerType()->isBooleanType();
618  return false;
619}
620
621llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
622  // Bool has a different representation in memory than in registers.
623  if (Ty->isBooleanType() || isBooleanUnderlyingType(Ty)) {
624    // This should really always be an i1, but sometimes it's already
625    // an i8, and it's awkward to track those cases down.
626    if (Value->getType()->isIntegerTy(1))
627      return Builder.CreateZExt(Value, Builder.getInt8Ty(), "frombool");
628    assert(Value->getType()->isIntegerTy(8) && "value rep of bool not i1/i8");
629  }
630
631  return Value;
632}
633
634llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
635  // Bool has a different representation in memory than in registers.
636  if (Ty->isBooleanType() || isBooleanUnderlyingType(Ty)) {
637    assert(Value->getType()->isIntegerTy(8) && "memory rep of bool not i8");
638    return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool");
639  }
640
641  return Value;
642}
643
644void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr,
645                                        bool Volatile, unsigned Alignment,
646                                        QualType Ty,
647                                        llvm::MDNode *TBAAInfo) {
648  Value = EmitToMemory(Value, Ty);
649  llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
650  if (Alignment)
651    Store->setAlignment(Alignment);
652  if (TBAAInfo)
653    CGM.DecorateInstruction(Store, TBAAInfo);
654}
655
656/// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
657/// method emits the address of the lvalue, then loads the result as an rvalue,
658/// returning the rvalue.
659RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, QualType ExprType) {
660  if (LV.isObjCWeak()) {
661    // load of a __weak object.
662    llvm::Value *AddrWeakObj = LV.getAddress();
663    return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
664                                                             AddrWeakObj));
665  }
666
667  if (LV.isSimple()) {
668    llvm::Value *Ptr = LV.getAddress();
669
670    // Functions are l-values that don't require loading.
671    if (ExprType->isFunctionType())
672      return RValue::get(Ptr);
673
674    // Everything needs a load.
675    return RValue::get(EmitLoadOfScalar(Ptr, LV.isVolatileQualified(),
676                                        LV.getAlignment(), ExprType,
677                                        LV.getTBAAInfo()));
678
679  }
680
681  if (LV.isVectorElt()) {
682    llvm::Value *Vec = Builder.CreateLoad(LV.getVectorAddr(),
683                                          LV.isVolatileQualified(), "tmp");
684    return RValue::get(Builder.CreateExtractElement(Vec, LV.getVectorIdx(),
685                                                    "vecext"));
686  }
687
688  // If this is a reference to a subset of the elements of a vector, either
689  // shuffle the input or extract/insert them as appropriate.
690  if (LV.isExtVectorElt())
691    return EmitLoadOfExtVectorElementLValue(LV, ExprType);
692
693  if (LV.isBitField())
694    return EmitLoadOfBitfieldLValue(LV, ExprType);
695
696  assert(LV.isPropertyRef() && "Unknown LValue type!");
697  return EmitLoadOfPropertyRefLValue(LV);
698}
699
700RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
701                                                 QualType ExprType) {
702  const CGBitFieldInfo &Info = LV.getBitFieldInfo();
703
704  // Get the output type.
705  const llvm::Type *ResLTy = ConvertType(ExprType);
706  unsigned ResSizeInBits = CGM.getTargetData().getTypeSizeInBits(ResLTy);
707
708  // Compute the result as an OR of all of the individual component accesses.
709  llvm::Value *Res = 0;
710  for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) {
711    const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i);
712
713    // Get the field pointer.
714    llvm::Value *Ptr = LV.getBitFieldBaseAddr();
715
716    // Only offset by the field index if used, so that incoming values are not
717    // required to be structures.
718    if (AI.FieldIndex)
719      Ptr = Builder.CreateStructGEP(Ptr, AI.FieldIndex, "bf.field");
720
721    // Offset by the byte offset, if used.
722    if (AI.FieldByteOffset) {
723      Ptr = EmitCastToVoidPtr(Ptr);
724      Ptr = Builder.CreateConstGEP1_32(Ptr, AI.FieldByteOffset,"bf.field.offs");
725    }
726
727    // Cast to the access type.
728    const llvm::Type *PTy = llvm::Type::getIntNPtrTy(getLLVMContext(),
729                                                     AI.AccessWidth,
730                                                    ExprType.getAddressSpace());
731    Ptr = Builder.CreateBitCast(Ptr, PTy);
732
733    // Perform the load.
734    llvm::LoadInst *Load = Builder.CreateLoad(Ptr, LV.isVolatileQualified());
735    if (AI.AccessAlignment)
736      Load->setAlignment(AI.AccessAlignment);
737
738    // Shift out unused low bits and mask out unused high bits.
739    llvm::Value *Val = Load;
740    if (AI.FieldBitStart)
741      Val = Builder.CreateLShr(Load, AI.FieldBitStart);
742    Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(AI.AccessWidth,
743                                                            AI.TargetBitWidth),
744                            "bf.clear");
745
746    // Extend or truncate to the target size.
747    if (AI.AccessWidth < ResSizeInBits)
748      Val = Builder.CreateZExt(Val, ResLTy);
749    else if (AI.AccessWidth > ResSizeInBits)
750      Val = Builder.CreateTrunc(Val, ResLTy);
751
752    // Shift into place, and OR into the result.
753    if (AI.TargetBitOffset)
754      Val = Builder.CreateShl(Val, AI.TargetBitOffset);
755    Res = Res ? Builder.CreateOr(Res, Val) : Val;
756  }
757
758  // If the bit-field is signed, perform the sign-extension.
759  //
760  // FIXME: This can easily be folded into the load of the high bits, which
761  // could also eliminate the mask of high bits in some situations.
762  if (Info.isSigned()) {
763    unsigned ExtraBits = ResSizeInBits - Info.getSize();
764    if (ExtraBits)
765      Res = Builder.CreateAShr(Builder.CreateShl(Res, ExtraBits),
766                               ExtraBits, "bf.val.sext");
767  }
768
769  return RValue::get(Res);
770}
771
772// If this is a reference to a subset of the elements of a vector, create an
773// appropriate shufflevector.
774RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV,
775                                                         QualType ExprType) {
776  llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddr(),
777                                        LV.isVolatileQualified(), "tmp");
778
779  const llvm::Constant *Elts = LV.getExtVectorElts();
780
781  // If the result of the expression is a non-vector type, we must be extracting
782  // a single element.  Just codegen as an extractelement.
783  const VectorType *ExprVT = ExprType->getAs<VectorType>();
784  if (!ExprVT) {
785    unsigned InIdx = getAccessedFieldNo(0, Elts);
786    llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx);
787    return RValue::get(Builder.CreateExtractElement(Vec, Elt, "tmp"));
788  }
789
790  // Always use shuffle vector to try to retain the original program structure
791  unsigned NumResultElts = ExprVT->getNumElements();
792
793  llvm::SmallVector<llvm::Constant*, 4> Mask;
794  for (unsigned i = 0; i != NumResultElts; ++i) {
795    unsigned InIdx = getAccessedFieldNo(i, Elts);
796    Mask.push_back(llvm::ConstantInt::get(Int32Ty, InIdx));
797  }
798
799  llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
800  Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()),
801                                    MaskV, "tmp");
802  return RValue::get(Vec);
803}
804
805
806
807/// EmitStoreThroughLValue - Store the specified rvalue into the specified
808/// lvalue, where both are guaranteed to the have the same type, and that type
809/// is 'Ty'.
810void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
811                                             QualType Ty) {
812  if (!Dst.isSimple()) {
813    if (Dst.isVectorElt()) {
814      // Read/modify/write the vector, inserting the new element.
815      llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddr(),
816                                            Dst.isVolatileQualified(), "tmp");
817      Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
818                                        Dst.getVectorIdx(), "vecins");
819      Builder.CreateStore(Vec, Dst.getVectorAddr(),Dst.isVolatileQualified());
820      return;
821    }
822
823    // If this is an update of extended vector elements, insert them as
824    // appropriate.
825    if (Dst.isExtVectorElt())
826      return EmitStoreThroughExtVectorComponentLValue(Src, Dst, Ty);
827
828    if (Dst.isBitField())
829      return EmitStoreThroughBitfieldLValue(Src, Dst, Ty);
830
831    assert(Dst.isPropertyRef() && "Unknown LValue type");
832    return EmitStoreThroughPropertyRefLValue(Src, Dst);
833  }
834
835  if (Dst.isObjCWeak() && !Dst.isNonGC()) {
836    // load of a __weak object.
837    llvm::Value *LvalueDst = Dst.getAddress();
838    llvm::Value *src = Src.getScalarVal();
839     CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
840    return;
841  }
842
843  if (Dst.isObjCStrong() && !Dst.isNonGC()) {
844    // load of a __strong object.
845    llvm::Value *LvalueDst = Dst.getAddress();
846    llvm::Value *src = Src.getScalarVal();
847    if (Dst.isObjCIvar()) {
848      assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
849      const llvm::Type *ResultType = ConvertType(getContext().LongTy);
850      llvm::Value *RHS = EmitScalarExpr(Dst.getBaseIvarExp());
851      llvm::Value *dst = RHS;
852      RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
853      llvm::Value *LHS =
854        Builder.CreatePtrToInt(LvalueDst, ResultType, "sub.ptr.lhs.cast");
855      llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
856      CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
857                                              BytesBetween);
858    } else if (Dst.isGlobalObjCRef()) {
859      CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
860                                                Dst.isThreadLocalRef());
861    }
862    else
863      CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
864    return;
865  }
866
867  assert(Src.isScalar() && "Can't emit an agg store with this method");
868  EmitStoreOfScalar(Src.getScalarVal(), Dst.getAddress(),
869                    Dst.isVolatileQualified(), Dst.getAlignment(), Ty,
870                    Dst.getTBAAInfo());
871}
872
873void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
874                                                     QualType Ty,
875                                                     llvm::Value **Result) {
876  const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
877
878  // Get the output type.
879  const llvm::Type *ResLTy = ConvertTypeForMem(Ty);
880  unsigned ResSizeInBits = CGM.getTargetData().getTypeSizeInBits(ResLTy);
881
882  // Get the source value, truncated to the width of the bit-field.
883  llvm::Value *SrcVal = Src.getScalarVal();
884
885  if (Ty->isBooleanType())
886    SrcVal = Builder.CreateIntCast(SrcVal, ResLTy, /*IsSigned=*/false);
887
888  SrcVal = Builder.CreateAnd(SrcVal, llvm::APInt::getLowBitsSet(ResSizeInBits,
889                                                                Info.getSize()),
890                             "bf.value");
891
892  // Return the new value of the bit-field, if requested.
893  if (Result) {
894    // Cast back to the proper type for result.
895    const llvm::Type *SrcTy = Src.getScalarVal()->getType();
896    llvm::Value *ReloadVal = Builder.CreateIntCast(SrcVal, SrcTy, false,
897                                                   "bf.reload.val");
898
899    // Sign extend if necessary.
900    if (Info.isSigned()) {
901      unsigned ExtraBits = ResSizeInBits - Info.getSize();
902      if (ExtraBits)
903        ReloadVal = Builder.CreateAShr(Builder.CreateShl(ReloadVal, ExtraBits),
904                                       ExtraBits, "bf.reload.sext");
905    }
906
907    *Result = ReloadVal;
908  }
909
910  // Iterate over the components, writing each piece to memory.
911  for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) {
912    const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i);
913
914    // Get the field pointer.
915    llvm::Value *Ptr = Dst.getBitFieldBaseAddr();
916    unsigned addressSpace =
917      cast<llvm::PointerType>(Ptr->getType())->getAddressSpace();
918
919    // Only offset by the field index if used, so that incoming values are not
920    // required to be structures.
921    if (AI.FieldIndex)
922      Ptr = Builder.CreateStructGEP(Ptr, AI.FieldIndex, "bf.field");
923
924    // Offset by the byte offset, if used.
925    if (AI.FieldByteOffset) {
926      Ptr = EmitCastToVoidPtr(Ptr);
927      Ptr = Builder.CreateConstGEP1_32(Ptr, AI.FieldByteOffset,"bf.field.offs");
928    }
929
930    // Cast to the access type.
931    const llvm::Type *AccessLTy =
932      llvm::Type::getIntNTy(getLLVMContext(), AI.AccessWidth);
933
934    const llvm::Type *PTy = AccessLTy->getPointerTo(addressSpace);
935    Ptr = Builder.CreateBitCast(Ptr, PTy);
936
937    // Extract the piece of the bit-field value to write in this access, limited
938    // to the values that are part of this access.
939    llvm::Value *Val = SrcVal;
940    if (AI.TargetBitOffset)
941      Val = Builder.CreateLShr(Val, AI.TargetBitOffset);
942    Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(ResSizeInBits,
943                                                            AI.TargetBitWidth));
944
945    // Extend or truncate to the access size.
946    if (ResSizeInBits < AI.AccessWidth)
947      Val = Builder.CreateZExt(Val, AccessLTy);
948    else if (ResSizeInBits > AI.AccessWidth)
949      Val = Builder.CreateTrunc(Val, AccessLTy);
950
951    // Shift into the position in memory.
952    if (AI.FieldBitStart)
953      Val = Builder.CreateShl(Val, AI.FieldBitStart);
954
955    // If necessary, load and OR in bits that are outside of the bit-field.
956    if (AI.TargetBitWidth != AI.AccessWidth) {
957      llvm::LoadInst *Load = Builder.CreateLoad(Ptr, Dst.isVolatileQualified());
958      if (AI.AccessAlignment)
959        Load->setAlignment(AI.AccessAlignment);
960
961      // Compute the mask for zeroing the bits that are part of the bit-field.
962      llvm::APInt InvMask =
963        ~llvm::APInt::getBitsSet(AI.AccessWidth, AI.FieldBitStart,
964                                 AI.FieldBitStart + AI.TargetBitWidth);
965
966      // Apply the mask and OR in to the value to write.
967      Val = Builder.CreateOr(Builder.CreateAnd(Load, InvMask), Val);
968    }
969
970    // Write the value.
971    llvm::StoreInst *Store = Builder.CreateStore(Val, Ptr,
972                                                 Dst.isVolatileQualified());
973    if (AI.AccessAlignment)
974      Store->setAlignment(AI.AccessAlignment);
975  }
976}
977
978void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
979                                                               LValue Dst,
980                                                               QualType Ty) {
981  // This access turns into a read/modify/write of the vector.  Load the input
982  // value now.
983  llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddr(),
984                                        Dst.isVolatileQualified(), "tmp");
985  const llvm::Constant *Elts = Dst.getExtVectorElts();
986
987  llvm::Value *SrcVal = Src.getScalarVal();
988
989  if (const VectorType *VTy = Ty->getAs<VectorType>()) {
990    unsigned NumSrcElts = VTy->getNumElements();
991    unsigned NumDstElts =
992       cast<llvm::VectorType>(Vec->getType())->getNumElements();
993    if (NumDstElts == NumSrcElts) {
994      // Use shuffle vector is the src and destination are the same number of
995      // elements and restore the vector mask since it is on the side it will be
996      // stored.
997      llvm::SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
998      for (unsigned i = 0; i != NumSrcElts; ++i) {
999        unsigned InIdx = getAccessedFieldNo(i, Elts);
1000        Mask[InIdx] = llvm::ConstantInt::get(Int32Ty, i);
1001      }
1002
1003      llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1004      Vec = Builder.CreateShuffleVector(SrcVal,
1005                                        llvm::UndefValue::get(Vec->getType()),
1006                                        MaskV, "tmp");
1007    } else if (NumDstElts > NumSrcElts) {
1008      // Extended the source vector to the same length and then shuffle it
1009      // into the destination.
1010      // FIXME: since we're shuffling with undef, can we just use the indices
1011      //        into that?  This could be simpler.
1012      llvm::SmallVector<llvm::Constant*, 4> ExtMask;
1013      unsigned i;
1014      for (i = 0; i != NumSrcElts; ++i)
1015        ExtMask.push_back(llvm::ConstantInt::get(Int32Ty, i));
1016      for (; i != NumDstElts; ++i)
1017        ExtMask.push_back(llvm::UndefValue::get(Int32Ty));
1018      llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask);
1019      llvm::Value *ExtSrcVal =
1020        Builder.CreateShuffleVector(SrcVal,
1021                                    llvm::UndefValue::get(SrcVal->getType()),
1022                                    ExtMaskV, "tmp");
1023      // build identity
1024      llvm::SmallVector<llvm::Constant*, 4> Mask;
1025      for (unsigned i = 0; i != NumDstElts; ++i)
1026        Mask.push_back(llvm::ConstantInt::get(Int32Ty, i));
1027
1028      // modify when what gets shuffled in
1029      for (unsigned i = 0; i != NumSrcElts; ++i) {
1030        unsigned Idx = getAccessedFieldNo(i, Elts);
1031        Mask[Idx] = llvm::ConstantInt::get(Int32Ty, i+NumDstElts);
1032      }
1033      llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1034      Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV, "tmp");
1035    } else {
1036      // We should never shorten the vector
1037      assert(0 && "unexpected shorten vector length");
1038    }
1039  } else {
1040    // If the Src is a scalar (not a vector) it must be updating one element.
1041    unsigned InIdx = getAccessedFieldNo(0, Elts);
1042    llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx);
1043    Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt, "tmp");
1044  }
1045
1046  Builder.CreateStore(Vec, Dst.getExtVectorAddr(), Dst.isVolatileQualified());
1047}
1048
1049// setObjCGCLValueClass - sets class of he lvalue for the purpose of
1050// generating write-barries API. It is currently a global, ivar,
1051// or neither.
1052static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
1053                                 LValue &LV) {
1054  if (Ctx.getLangOptions().getGCMode() == LangOptions::NonGC)
1055    return;
1056
1057  if (isa<ObjCIvarRefExpr>(E)) {
1058    LV.setObjCIvar(true);
1059    ObjCIvarRefExpr *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr*>(E));
1060    LV.setBaseIvarExp(Exp->getBase());
1061    LV.setObjCArray(E->getType()->isArrayType());
1062    return;
1063  }
1064
1065  if (const DeclRefExpr *Exp = dyn_cast<DeclRefExpr>(E)) {
1066    if (const VarDecl *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
1067      if (VD->hasGlobalStorage()) {
1068        LV.setGlobalObjCRef(true);
1069        LV.setThreadLocalRef(VD->isThreadSpecified());
1070      }
1071    }
1072    LV.setObjCArray(E->getType()->isArrayType());
1073    return;
1074  }
1075
1076  if (const UnaryOperator *Exp = dyn_cast<UnaryOperator>(E)) {
1077    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1078    return;
1079  }
1080
1081  if (const ParenExpr *Exp = dyn_cast<ParenExpr>(E)) {
1082    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1083    if (LV.isObjCIvar()) {
1084      // If cast is to a structure pointer, follow gcc's behavior and make it
1085      // a non-ivar write-barrier.
1086      QualType ExpTy = E->getType();
1087      if (ExpTy->isPointerType())
1088        ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
1089      if (ExpTy->isRecordType())
1090        LV.setObjCIvar(false);
1091    }
1092    return;
1093  }
1094  if (const ImplicitCastExpr *Exp = dyn_cast<ImplicitCastExpr>(E)) {
1095    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1096    return;
1097  }
1098
1099  if (const CStyleCastExpr *Exp = dyn_cast<CStyleCastExpr>(E)) {
1100    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1101    return;
1102  }
1103
1104  if (const ArraySubscriptExpr *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
1105    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
1106    if (LV.isObjCIvar() && !LV.isObjCArray())
1107      // Using array syntax to assigning to what an ivar points to is not
1108      // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
1109      LV.setObjCIvar(false);
1110    else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
1111      // Using array syntax to assigning to what global points to is not
1112      // same as assigning to the global itself. {id *G;} G[i] = 0;
1113      LV.setGlobalObjCRef(false);
1114    return;
1115  }
1116
1117  if (const MemberExpr *Exp = dyn_cast<MemberExpr>(E)) {
1118    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
1119    // We don't know if member is an 'ivar', but this flag is looked at
1120    // only in the context of LV.isObjCIvar().
1121    LV.setObjCArray(E->getType()->isArrayType());
1122    return;
1123  }
1124}
1125
1126static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
1127                                      const Expr *E, const VarDecl *VD) {
1128  assert((VD->hasExternalStorage() || VD->isFileVarDecl()) &&
1129         "Var decl must have external storage or be a file var decl!");
1130
1131  llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
1132  if (VD->getType()->isReferenceType())
1133    V = CGF.Builder.CreateLoad(V, "tmp");
1134  unsigned Alignment = CGF.getContext().getDeclAlign(VD).getQuantity();
1135  LValue LV = CGF.MakeAddrLValue(V, E->getType(), Alignment);
1136  setObjCGCLValueClass(CGF.getContext(), E, LV);
1137  return LV;
1138}
1139
1140static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
1141                                      const Expr *E, const FunctionDecl *FD) {
1142  llvm::Value *V = CGF.CGM.GetAddrOfFunction(FD);
1143  if (!FD->hasPrototype()) {
1144    if (const FunctionProtoType *Proto =
1145            FD->getType()->getAs<FunctionProtoType>()) {
1146      // Ugly case: for a K&R-style definition, the type of the definition
1147      // isn't the same as the type of a use.  Correct for this with a
1148      // bitcast.
1149      QualType NoProtoType =
1150          CGF.getContext().getFunctionNoProtoType(Proto->getResultType());
1151      NoProtoType = CGF.getContext().getPointerType(NoProtoType);
1152      V = CGF.Builder.CreateBitCast(V, CGF.ConvertType(NoProtoType), "tmp");
1153    }
1154  }
1155  unsigned Alignment = CGF.getContext().getDeclAlign(FD).getQuantity();
1156  return CGF.MakeAddrLValue(V, E->getType(), Alignment);
1157}
1158
1159LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
1160  const NamedDecl *ND = E->getDecl();
1161  unsigned Alignment = getContext().getDeclAlign(ND).getQuantity();
1162
1163  if (ND->hasAttr<WeakRefAttr>()) {
1164    const ValueDecl *VD = cast<ValueDecl>(ND);
1165    llvm::Constant *Aliasee = CGM.GetWeakRefReference(VD);
1166    return MakeAddrLValue(Aliasee, E->getType(), Alignment);
1167  }
1168
1169  if (const VarDecl *VD = dyn_cast<VarDecl>(ND)) {
1170
1171    // Check if this is a global variable.
1172    if (VD->hasExternalStorage() || VD->isFileVarDecl())
1173      return EmitGlobalVarDeclLValue(*this, E, VD);
1174
1175    bool NonGCable = VD->hasLocalStorage() &&
1176                     !VD->getType()->isReferenceType() &&
1177                     !VD->hasAttr<BlocksAttr>();
1178
1179    llvm::Value *V = LocalDeclMap[VD];
1180    if (!V && VD->isStaticLocal())
1181      V = CGM.getStaticLocalDeclAddress(VD);
1182    assert(V && "DeclRefExpr not entered in LocalDeclMap?");
1183
1184    if (VD->hasAttr<BlocksAttr>())
1185      V = BuildBlockByrefAddress(V, VD);
1186
1187    if (VD->getType()->isReferenceType())
1188      V = Builder.CreateLoad(V, "tmp");
1189
1190    LValue LV = MakeAddrLValue(V, E->getType(), Alignment);
1191    if (NonGCable) {
1192      LV.getQuals().removeObjCGCAttr();
1193      LV.setNonGC(true);
1194    }
1195    setObjCGCLValueClass(getContext(), E, LV);
1196    return LV;
1197  }
1198
1199  if (const FunctionDecl *fn = dyn_cast<FunctionDecl>(ND))
1200    return EmitFunctionDeclLValue(*this, E, fn);
1201
1202  assert(false && "Unhandled DeclRefExpr");
1203
1204  // an invalid LValue, but the assert will
1205  // ensure that this point is never reached.
1206  return LValue();
1207}
1208
1209LValue CodeGenFunction::EmitBlockDeclRefLValue(const BlockDeclRefExpr *E) {
1210  unsigned Alignment =
1211    getContext().getDeclAlign(E->getDecl()).getQuantity();
1212  return MakeAddrLValue(GetAddrOfBlockDecl(E), E->getType(), Alignment);
1213}
1214
1215LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
1216  // __extension__ doesn't affect lvalue-ness.
1217  if (E->getOpcode() == UO_Extension)
1218    return EmitLValue(E->getSubExpr());
1219
1220  QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
1221  switch (E->getOpcode()) {
1222  default: assert(0 && "Unknown unary operator lvalue!");
1223  case UO_Deref: {
1224    QualType T = E->getSubExpr()->getType()->getPointeeType();
1225    assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
1226
1227    LValue LV = MakeAddrLValue(EmitScalarExpr(E->getSubExpr()), T);
1228    LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
1229
1230    // We should not generate __weak write barrier on indirect reference
1231    // of a pointer to object; as in void foo (__weak id *param); *param = 0;
1232    // But, we continue to generate __strong write barrier on indirect write
1233    // into a pointer to object.
1234    if (getContext().getLangOptions().ObjC1 &&
1235        getContext().getLangOptions().getGCMode() != LangOptions::NonGC &&
1236        LV.isObjCWeak())
1237      LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
1238    return LV;
1239  }
1240  case UO_Real:
1241  case UO_Imag: {
1242    LValue LV = EmitLValue(E->getSubExpr());
1243    assert(LV.isSimple() && "real/imag on non-ordinary l-value");
1244    llvm::Value *Addr = LV.getAddress();
1245
1246    // real and imag are valid on scalars.  This is a faster way of
1247    // testing that.
1248    if (!cast<llvm::PointerType>(Addr->getType())
1249           ->getElementType()->isStructTy()) {
1250      assert(E->getSubExpr()->getType()->isArithmeticType());
1251      return LV;
1252    }
1253
1254    assert(E->getSubExpr()->getType()->isAnyComplexType());
1255
1256    unsigned Idx = E->getOpcode() == UO_Imag;
1257    return MakeAddrLValue(Builder.CreateStructGEP(LV.getAddress(),
1258                                                  Idx, "idx"),
1259                          ExprTy);
1260  }
1261  case UO_PreInc:
1262  case UO_PreDec: {
1263    LValue LV = EmitLValue(E->getSubExpr());
1264    bool isInc = E->getOpcode() == UO_PreInc;
1265
1266    if (E->getType()->isAnyComplexType())
1267      EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
1268    else
1269      EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
1270    return LV;
1271  }
1272  }
1273}
1274
1275LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
1276  return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
1277                        E->getType());
1278}
1279
1280LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
1281  return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
1282                        E->getType());
1283}
1284
1285
1286LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
1287  switch (E->getIdentType()) {
1288  default:
1289    return EmitUnsupportedLValue(E, "predefined expression");
1290
1291  case PredefinedExpr::Func:
1292  case PredefinedExpr::Function:
1293  case PredefinedExpr::PrettyFunction: {
1294    unsigned Type = E->getIdentType();
1295    std::string GlobalVarName;
1296
1297    switch (Type) {
1298    default: assert(0 && "Invalid type");
1299    case PredefinedExpr::Func:
1300      GlobalVarName = "__func__.";
1301      break;
1302    case PredefinedExpr::Function:
1303      GlobalVarName = "__FUNCTION__.";
1304      break;
1305    case PredefinedExpr::PrettyFunction:
1306      GlobalVarName = "__PRETTY_FUNCTION__.";
1307      break;
1308    }
1309
1310    llvm::StringRef FnName = CurFn->getName();
1311    if (FnName.startswith("\01"))
1312      FnName = FnName.substr(1);
1313    GlobalVarName += FnName;
1314
1315    const Decl *CurDecl = CurCodeDecl;
1316    if (CurDecl == 0)
1317      CurDecl = getContext().getTranslationUnitDecl();
1318
1319    std::string FunctionName =
1320        (isa<BlockDecl>(CurDecl)
1321         ? FnName.str()
1322         : PredefinedExpr::ComputeName((PredefinedExpr::IdentType)Type, CurDecl));
1323
1324    llvm::Constant *C =
1325      CGM.GetAddrOfConstantCString(FunctionName, GlobalVarName.c_str());
1326    return MakeAddrLValue(C, E->getType());
1327  }
1328  }
1329}
1330
1331llvm::BasicBlock *CodeGenFunction::getTrapBB() {
1332  const CodeGenOptions &GCO = CGM.getCodeGenOpts();
1333
1334  // If we are not optimzing, don't collapse all calls to trap in the function
1335  // to the same call, that way, in the debugger they can see which operation
1336  // did in fact fail.  If we are optimizing, we collapse all calls to trap down
1337  // to just one per function to save on codesize.
1338  if (GCO.OptimizationLevel && TrapBB)
1339    return TrapBB;
1340
1341  llvm::BasicBlock *Cont = 0;
1342  if (HaveInsertPoint()) {
1343    Cont = createBasicBlock("cont");
1344    EmitBranch(Cont);
1345  }
1346  TrapBB = createBasicBlock("trap");
1347  EmitBlock(TrapBB);
1348
1349  llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::trap, 0, 0);
1350  llvm::CallInst *TrapCall = Builder.CreateCall(F);
1351  TrapCall->setDoesNotReturn();
1352  TrapCall->setDoesNotThrow();
1353  Builder.CreateUnreachable();
1354
1355  if (Cont)
1356    EmitBlock(Cont);
1357  return TrapBB;
1358}
1359
1360/// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
1361/// array to pointer, return the array subexpression.
1362static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
1363  // If this isn't just an array->pointer decay, bail out.
1364  const CastExpr *CE = dyn_cast<CastExpr>(E);
1365  if (CE == 0 || CE->getCastKind() != CK_ArrayToPointerDecay)
1366    return 0;
1367
1368  // If this is a decay from variable width array, bail out.
1369  const Expr *SubExpr = CE->getSubExpr();
1370  if (SubExpr->getType()->isVariableArrayType())
1371    return 0;
1372
1373  return SubExpr;
1374}
1375
1376LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E) {
1377  // The index must always be an integer, which is not an aggregate.  Emit it.
1378  llvm::Value *Idx = EmitScalarExpr(E->getIdx());
1379  QualType IdxTy  = E->getIdx()->getType();
1380  bool IdxSigned = IdxTy->isSignedIntegerType();
1381
1382  // If the base is a vector type, then we are forming a vector element lvalue
1383  // with this subscript.
1384  if (E->getBase()->getType()->isVectorType()) {
1385    // Emit the vector as an lvalue to get its address.
1386    LValue LHS = EmitLValue(E->getBase());
1387    assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
1388    Idx = Builder.CreateIntCast(Idx, Int32Ty, IdxSigned, "vidx");
1389    return LValue::MakeVectorElt(LHS.getAddress(), Idx,
1390                                 E->getBase()->getType().getCVRQualifiers());
1391  }
1392
1393  // Extend or truncate the index type to 32 or 64-bits.
1394  if (Idx->getType() != IntPtrTy)
1395    Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
1396
1397  // FIXME: As llvm implements the object size checking, this can come out.
1398  if (CatchUndefined) {
1399    if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E->getBase())){
1400      if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr())) {
1401        if (ICE->getCastKind() == CK_ArrayToPointerDecay) {
1402          if (const ConstantArrayType *CAT
1403              = getContext().getAsConstantArrayType(DRE->getType())) {
1404            llvm::APInt Size = CAT->getSize();
1405            llvm::BasicBlock *Cont = createBasicBlock("cont");
1406            Builder.CreateCondBr(Builder.CreateICmpULE(Idx,
1407                                  llvm::ConstantInt::get(Idx->getType(), Size)),
1408                                 Cont, getTrapBB());
1409            EmitBlock(Cont);
1410          }
1411        }
1412      }
1413    }
1414  }
1415
1416  // We know that the pointer points to a type of the correct size, unless the
1417  // size is a VLA or Objective-C interface.
1418  llvm::Value *Address = 0;
1419  if (const VariableArrayType *VAT =
1420        getContext().getAsVariableArrayType(E->getType())) {
1421    llvm::Value *VLASize = GetVLASize(VAT);
1422
1423    Idx = Builder.CreateMul(Idx, VLASize);
1424
1425    // The base must be a pointer, which is not an aggregate.  Emit it.
1426    llvm::Value *Base = EmitScalarExpr(E->getBase());
1427
1428    Address = EmitCastToVoidPtr(Base);
1429    if (getContext().getLangOptions().isSignedOverflowDefined())
1430      Address = Builder.CreateGEP(Address, Idx, "arrayidx");
1431    else
1432      Address = Builder.CreateInBoundsGEP(Address, Idx, "arrayidx");
1433    Address = Builder.CreateBitCast(Address, Base->getType());
1434  } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
1435    // Indexing over an interface, as in "NSString *P; P[4];"
1436    llvm::Value *InterfaceSize =
1437      llvm::ConstantInt::get(Idx->getType(),
1438          getContext().getTypeSizeInChars(OIT).getQuantity());
1439
1440    Idx = Builder.CreateMul(Idx, InterfaceSize);
1441
1442    // The base must be a pointer, which is not an aggregate.  Emit it.
1443    llvm::Value *Base = EmitScalarExpr(E->getBase());
1444    Address = EmitCastToVoidPtr(Base);
1445    Address = Builder.CreateGEP(Address, Idx, "arrayidx");
1446    Address = Builder.CreateBitCast(Address, Base->getType());
1447  } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
1448    // If this is A[i] where A is an array, the frontend will have decayed the
1449    // base to be a ArrayToPointerDecay implicit cast.  While correct, it is
1450    // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
1451    // "gep x, i" here.  Emit one "gep A, 0, i".
1452    assert(Array->getType()->isArrayType() &&
1453           "Array to pointer decay must have array source type!");
1454    llvm::Value *ArrayPtr = EmitLValue(Array).getAddress();
1455    llvm::Value *Zero = llvm::ConstantInt::get(Int32Ty, 0);
1456    llvm::Value *Args[] = { Zero, Idx };
1457
1458    if (getContext().getLangOptions().isSignedOverflowDefined())
1459      Address = Builder.CreateGEP(ArrayPtr, Args, Args+2, "arrayidx");
1460    else
1461      Address = Builder.CreateInBoundsGEP(ArrayPtr, Args, Args+2, "arrayidx");
1462  } else {
1463    // The base must be a pointer, which is not an aggregate.  Emit it.
1464    llvm::Value *Base = EmitScalarExpr(E->getBase());
1465    if (getContext().getLangOptions().isSignedOverflowDefined())
1466      Address = Builder.CreateGEP(Base, Idx, "arrayidx");
1467    else
1468      Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
1469  }
1470
1471  QualType T = E->getBase()->getType()->getPointeeType();
1472  assert(!T.isNull() &&
1473         "CodeGenFunction::EmitArraySubscriptExpr(): Illegal base type");
1474
1475  LValue LV = MakeAddrLValue(Address, T);
1476  LV.getQuals().setAddressSpace(E->getBase()->getType().getAddressSpace());
1477
1478  if (getContext().getLangOptions().ObjC1 &&
1479      getContext().getLangOptions().getGCMode() != LangOptions::NonGC) {
1480    LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
1481    setObjCGCLValueClass(getContext(), E, LV);
1482  }
1483  return LV;
1484}
1485
1486static
1487llvm::Constant *GenerateConstantVector(llvm::LLVMContext &VMContext,
1488                                       llvm::SmallVector<unsigned, 4> &Elts) {
1489  llvm::SmallVector<llvm::Constant*, 4> CElts;
1490
1491  const llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext);
1492  for (unsigned i = 0, e = Elts.size(); i != e; ++i)
1493    CElts.push_back(llvm::ConstantInt::get(Int32Ty, Elts[i]));
1494
1495  return llvm::ConstantVector::get(CElts);
1496}
1497
1498LValue CodeGenFunction::
1499EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
1500  // Emit the base vector as an l-value.
1501  LValue Base;
1502
1503  // ExtVectorElementExpr's base can either be a vector or pointer to vector.
1504  if (E->isArrow()) {
1505    // If it is a pointer to a vector, emit the address and form an lvalue with
1506    // it.
1507    llvm::Value *Ptr = EmitScalarExpr(E->getBase());
1508    const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
1509    Base = MakeAddrLValue(Ptr, PT->getPointeeType());
1510    Base.getQuals().removeObjCGCAttr();
1511  } else if (E->getBase()->isGLValue()) {
1512    // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
1513    // emit the base as an lvalue.
1514    assert(E->getBase()->getType()->isVectorType());
1515    Base = EmitLValue(E->getBase());
1516  } else {
1517    // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
1518    assert(E->getBase()->getType()->getAs<VectorType>() &&
1519           "Result must be a vector");
1520    llvm::Value *Vec = EmitScalarExpr(E->getBase());
1521
1522    // Store the vector to memory (because LValue wants an address).
1523    llvm::Value *VecMem = CreateMemTemp(E->getBase()->getType());
1524    Builder.CreateStore(Vec, VecMem);
1525    Base = MakeAddrLValue(VecMem, E->getBase()->getType());
1526  }
1527
1528  // Encode the element access list into a vector of unsigned indices.
1529  llvm::SmallVector<unsigned, 4> Indices;
1530  E->getEncodedElementAccess(Indices);
1531
1532  if (Base.isSimple()) {
1533    llvm::Constant *CV = GenerateConstantVector(getLLVMContext(), Indices);
1534    return LValue::MakeExtVectorElt(Base.getAddress(), CV,
1535                                    Base.getVRQualifiers());
1536  }
1537  assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
1538
1539  llvm::Constant *BaseElts = Base.getExtVectorElts();
1540  llvm::SmallVector<llvm::Constant *, 4> CElts;
1541
1542  for (unsigned i = 0, e = Indices.size(); i != e; ++i) {
1543    if (isa<llvm::ConstantAggregateZero>(BaseElts))
1544      CElts.push_back(llvm::ConstantInt::get(Int32Ty, 0));
1545    else
1546      CElts.push_back(cast<llvm::Constant>(BaseElts->getOperand(Indices[i])));
1547  }
1548  llvm::Constant *CV = llvm::ConstantVector::get(CElts);
1549  return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV,
1550                                  Base.getVRQualifiers());
1551}
1552
1553LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
1554  bool isNonGC = false;
1555  Expr *BaseExpr = E->getBase();
1556  llvm::Value *BaseValue = NULL;
1557  Qualifiers BaseQuals;
1558
1559  // If this is s.x, emit s as an lvalue.  If it is s->x, emit s as a scalar.
1560  if (E->isArrow()) {
1561    BaseValue = EmitScalarExpr(BaseExpr);
1562    const PointerType *PTy =
1563      BaseExpr->getType()->getAs<PointerType>();
1564    BaseQuals = PTy->getPointeeType().getQualifiers();
1565  } else {
1566    LValue BaseLV = EmitLValue(BaseExpr);
1567    if (BaseLV.isNonGC())
1568      isNonGC = true;
1569    // FIXME: this isn't right for bitfields.
1570    BaseValue = BaseLV.getAddress();
1571    QualType BaseTy = BaseExpr->getType();
1572    BaseQuals = BaseTy.getQualifiers();
1573  }
1574
1575  NamedDecl *ND = E->getMemberDecl();
1576  if (FieldDecl *Field = dyn_cast<FieldDecl>(ND)) {
1577    LValue LV = EmitLValueForField(BaseValue, Field,
1578                                   BaseQuals.getCVRQualifiers());
1579    LV.setNonGC(isNonGC);
1580    setObjCGCLValueClass(getContext(), E, LV);
1581    return LV;
1582  }
1583
1584  if (VarDecl *VD = dyn_cast<VarDecl>(ND))
1585    return EmitGlobalVarDeclLValue(*this, E, VD);
1586
1587  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
1588    return EmitFunctionDeclLValue(*this, E, FD);
1589
1590  assert(false && "Unhandled member declaration!");
1591  return LValue();
1592}
1593
1594LValue CodeGenFunction::EmitLValueForBitfield(llvm::Value *BaseValue,
1595                                              const FieldDecl *Field,
1596                                              unsigned CVRQualifiers) {
1597  const CGRecordLayout &RL =
1598    CGM.getTypes().getCGRecordLayout(Field->getParent());
1599  const CGBitFieldInfo &Info = RL.getBitFieldInfo(Field);
1600  return LValue::MakeBitfield(BaseValue, Info,
1601                             Field->getType().getCVRQualifiers()|CVRQualifiers);
1602}
1603
1604/// EmitLValueForAnonRecordField - Given that the field is a member of
1605/// an anonymous struct or union buried inside a record, and given
1606/// that the base value is a pointer to the enclosing record, derive
1607/// an lvalue for the ultimate field.
1608LValue CodeGenFunction::EmitLValueForAnonRecordField(llvm::Value *BaseValue,
1609                                             const IndirectFieldDecl *Field,
1610                                                     unsigned CVRQualifiers) {
1611  IndirectFieldDecl::chain_iterator I = Field->chain_begin(),
1612    IEnd = Field->chain_end();
1613  while (true) {
1614    LValue LV = EmitLValueForField(BaseValue, cast<FieldDecl>(*I), CVRQualifiers);
1615    if (++I == IEnd) return LV;
1616
1617    assert(LV.isSimple());
1618    BaseValue = LV.getAddress();
1619    CVRQualifiers |= LV.getVRQualifiers();
1620  }
1621}
1622
1623LValue CodeGenFunction::EmitLValueForField(llvm::Value *baseAddr,
1624                                           const FieldDecl *field,
1625                                           unsigned cvr) {
1626  if (field->isBitField())
1627    return EmitLValueForBitfield(baseAddr, field, cvr);
1628
1629  const RecordDecl *rec = field->getParent();
1630  QualType type = field->getType();
1631
1632  bool mayAlias = rec->hasAttr<MayAliasAttr>();
1633
1634  llvm::Value *addr;
1635  if (rec->isUnion()) {
1636    // For unions, we just cast to the appropriate type.
1637    assert(!type->isReferenceType() && "union has reference member");
1638
1639    const llvm::Type *llvmType = CGM.getTypes().ConvertTypeForMem(type);
1640    unsigned AS =
1641      cast<llvm::PointerType>(baseAddr->getType())->getAddressSpace();
1642    addr = Builder.CreateBitCast(baseAddr, llvmType->getPointerTo(AS),
1643                                 field->getName());
1644  } else {
1645    // For structs, we GEP to the field that the record layout suggests.
1646    unsigned idx = CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
1647    addr = Builder.CreateStructGEP(baseAddr, idx, field->getName());
1648
1649    // If this is a reference field, load the reference right now.
1650    if (const ReferenceType *refType = type->getAs<ReferenceType>()) {
1651      llvm::LoadInst *load = Builder.CreateLoad(addr, "ref");
1652      if (cvr & Qualifiers::Volatile) load->setVolatile(true);
1653
1654      if (CGM.shouldUseTBAA()) {
1655        llvm::MDNode *tbaa;
1656        if (mayAlias)
1657          tbaa = CGM.getTBAAInfo(getContext().CharTy);
1658        else
1659          tbaa = CGM.getTBAAInfo(type);
1660        CGM.DecorateInstruction(load, tbaa);
1661      }
1662
1663      addr = load;
1664      mayAlias = false;
1665      type = refType->getPointeeType();
1666      cvr = 0; // qualifiers don't recursively apply to referencee
1667    }
1668  }
1669
1670  unsigned alignment = getContext().getDeclAlign(field).getQuantity();
1671  LValue LV = MakeAddrLValue(addr, type, alignment);
1672  LV.getQuals().addCVRQualifiers(cvr);
1673
1674  // __weak attribute on a field is ignored.
1675  if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
1676    LV.getQuals().removeObjCGCAttr();
1677
1678  // Fields of may_alias structs act like 'char' for TBAA purposes.
1679  // FIXME: this should get propagated down through anonymous structs
1680  // and unions.
1681  if (mayAlias && LV.getTBAAInfo())
1682    LV.setTBAAInfo(CGM.getTBAAInfo(getContext().CharTy));
1683
1684  return LV;
1685}
1686
1687LValue
1688CodeGenFunction::EmitLValueForFieldInitialization(llvm::Value *BaseValue,
1689                                                  const FieldDecl *Field,
1690                                                  unsigned CVRQualifiers) {
1691  QualType FieldType = Field->getType();
1692
1693  if (!FieldType->isReferenceType())
1694    return EmitLValueForField(BaseValue, Field, CVRQualifiers);
1695
1696  const CGRecordLayout &RL =
1697    CGM.getTypes().getCGRecordLayout(Field->getParent());
1698  unsigned idx = RL.getLLVMFieldNo(Field);
1699  llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx, "tmp");
1700
1701  assert(!FieldType.getObjCGCAttr() && "fields cannot have GC attrs");
1702
1703  unsigned Alignment = getContext().getDeclAlign(Field).getQuantity();
1704  return MakeAddrLValue(V, FieldType, Alignment);
1705}
1706
1707LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
1708  llvm::Value *DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
1709  const Expr *InitExpr = E->getInitializer();
1710  LValue Result = MakeAddrLValue(DeclPtr, E->getType());
1711
1712  EmitAnyExprToMem(InitExpr, DeclPtr, /*Volatile*/ false, /*Init*/ true);
1713
1714  return Result;
1715}
1716
1717LValue CodeGenFunction::
1718EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) {
1719  if (!expr->isGLValue()) {
1720    // ?: here should be an aggregate.
1721    assert((hasAggregateLLVMType(expr->getType()) &&
1722            !expr->getType()->isAnyComplexType()) &&
1723           "Unexpected conditional operator!");
1724    return EmitAggExprToLValue(expr);
1725  }
1726
1727  const Expr *condExpr = expr->getCond();
1728  bool CondExprBool;
1729  if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
1730    const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr();
1731    if (!CondExprBool) std::swap(live, dead);
1732
1733    if (!ContainsLabel(dead))
1734      return EmitLValue(live);
1735  }
1736
1737  OpaqueValueMapping binding(*this, expr);
1738
1739  llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true");
1740  llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false");
1741  llvm::BasicBlock *contBlock = createBasicBlock("cond.end");
1742
1743  ConditionalEvaluation eval(*this);
1744  EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock);
1745
1746  // Any temporaries created here are conditional.
1747  EmitBlock(lhsBlock);
1748  eval.begin(*this);
1749  LValue lhs = EmitLValue(expr->getTrueExpr());
1750  eval.end(*this);
1751
1752  if (!lhs.isSimple())
1753    return EmitUnsupportedLValue(expr, "conditional operator");
1754
1755  lhsBlock = Builder.GetInsertBlock();
1756  Builder.CreateBr(contBlock);
1757
1758  // Any temporaries created here are conditional.
1759  EmitBlock(rhsBlock);
1760  eval.begin(*this);
1761  LValue rhs = EmitLValue(expr->getFalseExpr());
1762  eval.end(*this);
1763  if (!rhs.isSimple())
1764    return EmitUnsupportedLValue(expr, "conditional operator");
1765  rhsBlock = Builder.GetInsertBlock();
1766
1767  EmitBlock(contBlock);
1768
1769  llvm::PHINode *phi = Builder.CreatePHI(lhs.getAddress()->getType(),
1770                                         "cond-lvalue");
1771  phi->reserveOperandSpace(2);
1772  phi->addIncoming(lhs.getAddress(), lhsBlock);
1773  phi->addIncoming(rhs.getAddress(), rhsBlock);
1774  return MakeAddrLValue(phi, expr->getType());
1775}
1776
1777/// EmitCastLValue - Casts are never lvalues unless that cast is a dynamic_cast.
1778/// If the cast is a dynamic_cast, we can have the usual lvalue result,
1779/// otherwise if a cast is needed by the code generator in an lvalue context,
1780/// then it must mean that we need the address of an aggregate in order to
1781/// access one of its fields.  This can happen for all the reasons that casts
1782/// are permitted with aggregate result, including noop aggregate casts, and
1783/// cast from scalar to union.
1784LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
1785  switch (E->getCastKind()) {
1786  case CK_ToVoid:
1787    return EmitUnsupportedLValue(E, "unexpected cast lvalue");
1788
1789  case CK_Dependent:
1790    llvm_unreachable("dependent cast kind in IR gen!");
1791
1792  case CK_GetObjCProperty: {
1793    LValue LV = EmitLValue(E->getSubExpr());
1794    assert(LV.isPropertyRef());
1795    RValue RV = EmitLoadOfPropertyRefLValue(LV);
1796
1797    // Property is an aggregate r-value.
1798    if (RV.isAggregate()) {
1799      return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
1800    }
1801
1802    // Implicit property returns an l-value.
1803    assert(RV.isScalar());
1804    return MakeAddrLValue(RV.getScalarVal(), E->getSubExpr()->getType());
1805  }
1806
1807  case CK_NoOp:
1808  case CK_LValueToRValue:
1809    if (!E->getSubExpr()->Classify(getContext()).isPRValue()
1810        || E->getType()->isRecordType())
1811      return EmitLValue(E->getSubExpr());
1812    // Fall through to synthesize a temporary.
1813
1814  case CK_BitCast:
1815  case CK_ArrayToPointerDecay:
1816  case CK_FunctionToPointerDecay:
1817  case CK_NullToMemberPointer:
1818  case CK_NullToPointer:
1819  case CK_IntegralToPointer:
1820  case CK_PointerToIntegral:
1821  case CK_PointerToBoolean:
1822  case CK_VectorSplat:
1823  case CK_IntegralCast:
1824  case CK_IntegralToBoolean:
1825  case CK_IntegralToFloating:
1826  case CK_FloatingToIntegral:
1827  case CK_FloatingToBoolean:
1828  case CK_FloatingCast:
1829  case CK_FloatingRealToComplex:
1830  case CK_FloatingComplexToReal:
1831  case CK_FloatingComplexToBoolean:
1832  case CK_FloatingComplexCast:
1833  case CK_FloatingComplexToIntegralComplex:
1834  case CK_IntegralRealToComplex:
1835  case CK_IntegralComplexToReal:
1836  case CK_IntegralComplexToBoolean:
1837  case CK_IntegralComplexCast:
1838  case CK_IntegralComplexToFloatingComplex:
1839  case CK_DerivedToBaseMemberPointer:
1840  case CK_BaseToDerivedMemberPointer:
1841  case CK_MemberPointerToBoolean:
1842  case CK_AnyPointerToBlockPointerCast: {
1843    // These casts only produce lvalues when we're binding a reference to a
1844    // temporary realized from a (converted) pure rvalue. Emit the expression
1845    // as a value, copy it into a temporary, and return an lvalue referring to
1846    // that temporary.
1847    llvm::Value *V = CreateMemTemp(E->getType(), "ref.temp");
1848    EmitAnyExprToMem(E, V, false, false);
1849    return MakeAddrLValue(V, E->getType());
1850  }
1851
1852  case CK_Dynamic: {
1853    LValue LV = EmitLValue(E->getSubExpr());
1854    llvm::Value *V = LV.getAddress();
1855    const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(E);
1856    return MakeAddrLValue(EmitDynamicCast(V, DCE), E->getType());
1857  }
1858
1859  case CK_ConstructorConversion:
1860  case CK_UserDefinedConversion:
1861  case CK_AnyPointerToObjCPointerCast:
1862    return EmitLValue(E->getSubExpr());
1863
1864  case CK_UncheckedDerivedToBase:
1865  case CK_DerivedToBase: {
1866    const RecordType *DerivedClassTy =
1867      E->getSubExpr()->getType()->getAs<RecordType>();
1868    CXXRecordDecl *DerivedClassDecl =
1869      cast<CXXRecordDecl>(DerivedClassTy->getDecl());
1870
1871    LValue LV = EmitLValue(E->getSubExpr());
1872    llvm::Value *This = LV.getAddress();
1873
1874    // Perform the derived-to-base conversion
1875    llvm::Value *Base =
1876      GetAddressOfBaseClass(This, DerivedClassDecl,
1877                            E->path_begin(), E->path_end(),
1878                            /*NullCheckValue=*/false);
1879
1880    return MakeAddrLValue(Base, E->getType());
1881  }
1882  case CK_ToUnion:
1883    return EmitAggExprToLValue(E);
1884  case CK_BaseToDerived: {
1885    const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
1886    CXXRecordDecl *DerivedClassDecl =
1887      cast<CXXRecordDecl>(DerivedClassTy->getDecl());
1888
1889    LValue LV = EmitLValue(E->getSubExpr());
1890
1891    // Perform the base-to-derived conversion
1892    llvm::Value *Derived =
1893      GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
1894                               E->path_begin(), E->path_end(),
1895                               /*NullCheckValue=*/false);
1896
1897    return MakeAddrLValue(Derived, E->getType());
1898  }
1899  case CK_LValueBitCast: {
1900    // This must be a reinterpret_cast (or c-style equivalent).
1901    const ExplicitCastExpr *CE = cast<ExplicitCastExpr>(E);
1902
1903    LValue LV = EmitLValue(E->getSubExpr());
1904    llvm::Value *V = Builder.CreateBitCast(LV.getAddress(),
1905                                           ConvertType(CE->getTypeAsWritten()));
1906    return MakeAddrLValue(V, E->getType());
1907  }
1908  case CK_ObjCObjectLValueCast: {
1909    LValue LV = EmitLValue(E->getSubExpr());
1910    QualType ToType = getContext().getLValueReferenceType(E->getType());
1911    llvm::Value *V = Builder.CreateBitCast(LV.getAddress(),
1912                                           ConvertType(ToType));
1913    return MakeAddrLValue(V, E->getType());
1914  }
1915  }
1916
1917  llvm_unreachable("Unhandled lvalue cast kind?");
1918}
1919
1920LValue CodeGenFunction::EmitNullInitializationLValue(
1921                                              const CXXScalarValueInitExpr *E) {
1922  QualType Ty = E->getType();
1923  LValue LV = MakeAddrLValue(CreateMemTemp(Ty), Ty);
1924  EmitNullInitialization(LV.getAddress(), Ty);
1925  return LV;
1926}
1927
1928LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
1929  assert(e->isGLValue() || e->getType()->isRecordType());
1930  return getOpaqueLValueMapping(e);
1931}
1932
1933//===--------------------------------------------------------------------===//
1934//                             Expression Emission
1935//===--------------------------------------------------------------------===//
1936
1937
1938RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
1939                                     ReturnValueSlot ReturnValue) {
1940  if (CGDebugInfo *DI = getDebugInfo()) {
1941    DI->setLocation(E->getLocStart());
1942    DI->UpdateLineDirectiveRegion(Builder);
1943    DI->EmitStopPoint(Builder);
1944  }
1945
1946  // Builtins never have block type.
1947  if (E->getCallee()->getType()->isBlockPointerType())
1948    return EmitBlockCallExpr(E, ReturnValue);
1949
1950  if (const CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(E))
1951    return EmitCXXMemberCallExpr(CE, ReturnValue);
1952
1953  const Decl *TargetDecl = 0;
1954  if (const ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E->getCallee())) {
1955    if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CE->getSubExpr())) {
1956      TargetDecl = DRE->getDecl();
1957      if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(TargetDecl))
1958        if (unsigned builtinID = FD->getBuiltinID())
1959          return EmitBuiltinExpr(FD, builtinID, E);
1960    }
1961  }
1962
1963  if (const CXXOperatorCallExpr *CE = dyn_cast<CXXOperatorCallExpr>(E))
1964    if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(TargetDecl))
1965      return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
1966
1967  if (isa<CXXPseudoDestructorExpr>(E->getCallee()->IgnoreParens())) {
1968    // C++ [expr.pseudo]p1:
1969    //   The result shall only be used as the operand for the function call
1970    //   operator (), and the result of such a call has type void. The only
1971    //   effect is the evaluation of the postfix-expression before the dot or
1972    //   arrow.
1973    EmitScalarExpr(E->getCallee());
1974    return RValue::get(0);
1975  }
1976
1977  llvm::Value *Callee = EmitScalarExpr(E->getCallee());
1978  return EmitCall(E->getCallee()->getType(), Callee, ReturnValue,
1979                  E->arg_begin(), E->arg_end(), TargetDecl);
1980}
1981
1982LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
1983  // Comma expressions just emit their LHS then their RHS as an l-value.
1984  if (E->getOpcode() == BO_Comma) {
1985    EmitIgnoredExpr(E->getLHS());
1986    EnsureInsertPoint();
1987    return EmitLValue(E->getRHS());
1988  }
1989
1990  if (E->getOpcode() == BO_PtrMemD ||
1991      E->getOpcode() == BO_PtrMemI)
1992    return EmitPointerToDataMemberBinaryExpr(E);
1993
1994  assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
1995
1996  if (!hasAggregateLLVMType(E->getType())) {
1997    // __block variables need the RHS evaluated first.
1998    RValue RV = EmitAnyExpr(E->getRHS());
1999    LValue LV = EmitLValue(E->getLHS());
2000    EmitStoreThroughLValue(RV, LV, E->getType());
2001    return LV;
2002  }
2003
2004  if (E->getType()->isAnyComplexType())
2005    return EmitComplexAssignmentLValue(E);
2006
2007  return EmitAggExprToLValue(E);
2008}
2009
2010LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
2011  RValue RV = EmitCallExpr(E);
2012
2013  if (!RV.isScalar())
2014    return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
2015
2016  assert(E->getCallReturnType()->isReferenceType() &&
2017         "Can't have a scalar return unless the return type is a "
2018         "reference type!");
2019
2020  return MakeAddrLValue(RV.getScalarVal(), E->getType());
2021}
2022
2023LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
2024  // FIXME: This shouldn't require another copy.
2025  return EmitAggExprToLValue(E);
2026}
2027
2028LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
2029  assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
2030         && "binding l-value to type which needs a temporary");
2031  AggValueSlot Slot = CreateAggTemp(E->getType(), "tmp");
2032  EmitCXXConstructExpr(E, Slot);
2033  return MakeAddrLValue(Slot.getAddr(), E->getType());
2034}
2035
2036LValue
2037CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
2038  return MakeAddrLValue(EmitCXXTypeidExpr(E), E->getType());
2039}
2040
2041LValue
2042CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
2043  AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
2044  Slot.setLifetimeExternallyManaged();
2045  EmitAggExpr(E->getSubExpr(), Slot);
2046  EmitCXXTemporary(E->getTemporary(), Slot.getAddr());
2047  return MakeAddrLValue(Slot.getAddr(), E->getType());
2048}
2049
2050LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
2051  RValue RV = EmitObjCMessageExpr(E);
2052
2053  if (!RV.isScalar())
2054    return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
2055
2056  assert(E->getMethodDecl()->getResultType()->isReferenceType() &&
2057         "Can't have a scalar return unless the return type is a "
2058         "reference type!");
2059
2060  return MakeAddrLValue(RV.getScalarVal(), E->getType());
2061}
2062
2063LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
2064  llvm::Value *V =
2065    CGM.getObjCRuntime().GetSelector(Builder, E->getSelector(), true);
2066  return MakeAddrLValue(V, E->getType());
2067}
2068
2069llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
2070                                             const ObjCIvarDecl *Ivar) {
2071  return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
2072}
2073
2074LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
2075                                          llvm::Value *BaseValue,
2076                                          const ObjCIvarDecl *Ivar,
2077                                          unsigned CVRQualifiers) {
2078  return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
2079                                                   Ivar, CVRQualifiers);
2080}
2081
2082LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
2083  // FIXME: A lot of the code below could be shared with EmitMemberExpr.
2084  llvm::Value *BaseValue = 0;
2085  const Expr *BaseExpr = E->getBase();
2086  Qualifiers BaseQuals;
2087  QualType ObjectTy;
2088  if (E->isArrow()) {
2089    BaseValue = EmitScalarExpr(BaseExpr);
2090    ObjectTy = BaseExpr->getType()->getPointeeType();
2091    BaseQuals = ObjectTy.getQualifiers();
2092  } else {
2093    LValue BaseLV = EmitLValue(BaseExpr);
2094    // FIXME: this isn't right for bitfields.
2095    BaseValue = BaseLV.getAddress();
2096    ObjectTy = BaseExpr->getType();
2097    BaseQuals = ObjectTy.getQualifiers();
2098  }
2099
2100  LValue LV =
2101    EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
2102                      BaseQuals.getCVRQualifiers());
2103  setObjCGCLValueClass(getContext(), E, LV);
2104  return LV;
2105}
2106
2107LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
2108  // Can only get l-value for message expression returning aggregate type
2109  RValue RV = EmitAnyExprToTemp(E);
2110  return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
2111}
2112
2113RValue CodeGenFunction::EmitCall(QualType CalleeType, llvm::Value *Callee,
2114                                 ReturnValueSlot ReturnValue,
2115                                 CallExpr::const_arg_iterator ArgBeg,
2116                                 CallExpr::const_arg_iterator ArgEnd,
2117                                 const Decl *TargetDecl) {
2118  // Get the actual function type. The callee type will always be a pointer to
2119  // function type or a block pointer type.
2120  assert(CalleeType->isFunctionPointerType() &&
2121         "Call must have function pointer type!");
2122
2123  CalleeType = getContext().getCanonicalType(CalleeType);
2124
2125  const FunctionType *FnType
2126    = cast<FunctionType>(cast<PointerType>(CalleeType)->getPointeeType());
2127
2128  CallArgList Args;
2129  EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), ArgBeg, ArgEnd);
2130
2131  return EmitCall(CGM.getTypes().getFunctionInfo(Args, FnType),
2132                  Callee, ReturnValue, Args, TargetDecl);
2133}
2134
2135LValue CodeGenFunction::
2136EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
2137  llvm::Value *BaseV;
2138  if (E->getOpcode() == BO_PtrMemI)
2139    BaseV = EmitScalarExpr(E->getLHS());
2140  else
2141    BaseV = EmitLValue(E->getLHS()).getAddress();
2142
2143  llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
2144
2145  const MemberPointerType *MPT
2146    = E->getRHS()->getType()->getAs<MemberPointerType>();
2147
2148  llvm::Value *AddV =
2149    CGM.getCXXABI().EmitMemberDataPointerAddress(*this, BaseV, OffsetV, MPT);
2150
2151  return MakeAddrLValue(AddV, MPT->getPointeeType());
2152}
2153