CGExpr.cpp revision b23a5a0a043b852ad643d366a0bb5b4c5a5c8881 
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  if (const ObjCPropertyRefExpr *PRE =
220      dyn_cast<ObjCPropertyRefExpr>(E->IgnoreParenImpCasts()))
221    if (PRE->getGetterResultType()->isReferenceType())
222      E = PRE;
223
224  RValue RV;
225  if (E->isGLValue()) {
226    // Emit the expression as an lvalue.
227    LValue LV = CGF.EmitLValue(E);
228    if (LV.isPropertyRef()) {
229      RV = CGF.EmitLoadOfPropertyRefLValue(LV);
230      return RV.getScalarVal();
231    }
232    if (LV.isSimple())
233      return LV.getAddress();
234
235    // We have to load the lvalue.
236    RV = CGF.EmitLoadOfLValue(LV, E->getType());
237  } else {
238    QualType ResultTy = E->getType();
239
240    llvm::SmallVector<SubobjectAdjustment, 2> Adjustments;
241    while (true) {
242      if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
243        E = PE->getSubExpr();
244        continue;
245      }
246
247      if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
248        if ((CE->getCastKind() == CK_DerivedToBase ||
249             CE->getCastKind() == CK_UncheckedDerivedToBase) &&
250            E->getType()->isRecordType()) {
251          E = CE->getSubExpr();
252          CXXRecordDecl *Derived
253            = cast<CXXRecordDecl>(E->getType()->getAs<RecordType>()->getDecl());
254          Adjustments.push_back(SubobjectAdjustment(CE, Derived));
255          continue;
256        }
257
258        if (CE->getCastKind() == CK_NoOp) {
259          E = CE->getSubExpr();
260          continue;
261        }
262      } else if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
263        if (!ME->isArrow() && ME->getBase()->isRValue()) {
264          assert(ME->getBase()->getType()->isRecordType());
265          if (FieldDecl *Field = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
266            E = ME->getBase();
267            Adjustments.push_back(SubobjectAdjustment(Field));
268            continue;
269          }
270        }
271      }
272
273      if (const OpaqueValueExpr *opaque = dyn_cast<OpaqueValueExpr>(E))
274        if (opaque->getType()->isRecordType())
275          return CGF.EmitOpaqueValueLValue(opaque).getAddress();
276
277      // Nothing changed.
278      break;
279    }
280
281    // Create a reference temporary if necessary.
282    AggValueSlot AggSlot = AggValueSlot::ignored();
283    if (CGF.hasAggregateLLVMType(E->getType()) &&
284        !E->getType()->isAnyComplexType()) {
285      ReferenceTemporary = CreateReferenceTemporary(CGF, E->getType(),
286                                                    InitializedDecl);
287      AggSlot = AggValueSlot::forAddr(ReferenceTemporary, false,
288                                      InitializedDecl != 0);
289    }
290
291    RV = CGF.EmitAnyExpr(E, AggSlot);
292
293    if (InitializedDecl) {
294      // Get the destructor for the reference temporary.
295      if (const RecordType *RT = E->getType()->getAs<RecordType>()) {
296        CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
297        if (!ClassDecl->hasTrivialDestructor())
298          ReferenceTemporaryDtor = ClassDecl->getDestructor();
299      }
300    }
301
302    // Check if need to perform derived-to-base casts and/or field accesses, to
303    // get from the temporary object we created (and, potentially, for which we
304    // extended the lifetime) to the subobject we're binding the reference to.
305    if (!Adjustments.empty()) {
306      llvm::Value *Object = RV.getAggregateAddr();
307      for (unsigned I = Adjustments.size(); I != 0; --I) {
308        SubobjectAdjustment &Adjustment = Adjustments[I-1];
309        switch (Adjustment.Kind) {
310        case SubobjectAdjustment::DerivedToBaseAdjustment:
311          Object =
312              CGF.GetAddressOfBaseClass(Object,
313                                        Adjustment.DerivedToBase.DerivedClass,
314                              Adjustment.DerivedToBase.BasePath->path_begin(),
315                              Adjustment.DerivedToBase.BasePath->path_end(),
316                                        /*NullCheckValue=*/false);
317          break;
318
319        case SubobjectAdjustment::FieldAdjustment: {
320          LValue LV =
321            CGF.EmitLValueForField(Object, Adjustment.Field, 0);
322          if (LV.isSimple()) {
323            Object = LV.getAddress();
324            break;
325          }
326
327          // For non-simple lvalues, we actually have to create a copy of
328          // the object we're binding to.
329          QualType T = Adjustment.Field->getType().getNonReferenceType()
330                                                  .getUnqualifiedType();
331          Object = CreateReferenceTemporary(CGF, T, InitializedDecl);
332          LValue TempLV = CGF.MakeAddrLValue(Object,
333                                             Adjustment.Field->getType());
334          CGF.EmitStoreThroughLValue(CGF.EmitLoadOfLValue(LV, T), TempLV, T);
335          break;
336        }
337
338        }
339      }
340
341      return Object;
342    }
343  }
344
345  if (RV.isAggregate())
346    return RV.getAggregateAddr();
347
348  // Create a temporary variable that we can bind the reference to.
349  ReferenceTemporary = CreateReferenceTemporary(CGF, E->getType(),
350                                                InitializedDecl);
351
352
353  unsigned Alignment =
354    CGF.getContext().getTypeAlignInChars(E->getType()).getQuantity();
355  if (RV.isScalar())
356    CGF.EmitStoreOfScalar(RV.getScalarVal(), ReferenceTemporary,
357                          /*Volatile=*/false, Alignment, E->getType());
358  else
359    CGF.StoreComplexToAddr(RV.getComplexVal(), ReferenceTemporary,
360                           /*Volatile=*/false);
361  return ReferenceTemporary;
362}
363
364RValue
365CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E,
366                                            const NamedDecl *InitializedDecl) {
367  llvm::Value *ReferenceTemporary = 0;
368  const CXXDestructorDecl *ReferenceTemporaryDtor = 0;
369  llvm::Value *Value = EmitExprForReferenceBinding(*this, E, ReferenceTemporary,
370                                                   ReferenceTemporaryDtor,
371                                                   InitializedDecl);
372  if (!ReferenceTemporaryDtor)
373    return RValue::get(Value);
374
375  // Make sure to call the destructor for the reference temporary.
376  if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(InitializedDecl)) {
377    if (VD->hasGlobalStorage()) {
378      llvm::Constant *DtorFn =
379        CGM.GetAddrOfCXXDestructor(ReferenceTemporaryDtor, Dtor_Complete);
380      EmitCXXGlobalDtorRegistration(DtorFn,
381                                    cast<llvm::Constant>(ReferenceTemporary));
382
383      return RValue::get(Value);
384    }
385  }
386
387  PushDestructorCleanup(ReferenceTemporaryDtor, ReferenceTemporary);
388
389  return RValue::get(Value);
390}
391
392
393/// getAccessedFieldNo - Given an encoded value and a result number, return the
394/// input field number being accessed.
395unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
396                                             const llvm::Constant *Elts) {
397  if (isa<llvm::ConstantAggregateZero>(Elts))
398    return 0;
399
400  return cast<llvm::ConstantInt>(Elts->getOperand(Idx))->getZExtValue();
401}
402
403void CodeGenFunction::EmitCheck(llvm::Value *Address, unsigned Size) {
404  if (!CatchUndefined)
405    return;
406
407  // This needs to be to the standard address space.
408  Address = Builder.CreateBitCast(Address, Int8PtrTy);
409
410  const llvm::Type *IntPtrT = IntPtrTy;
411  llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, &IntPtrT, 1);
412
413  // In time, people may want to control this and use a 1 here.
414  llvm::Value *Arg = Builder.getFalse();
415  llvm::Value *C = Builder.CreateCall2(F, Address, Arg);
416  llvm::BasicBlock *Cont = createBasicBlock();
417  llvm::BasicBlock *Check = createBasicBlock();
418  llvm::Value *NegativeOne = llvm::ConstantInt::get(IntPtrTy, -1ULL);
419  Builder.CreateCondBr(Builder.CreateICmpEQ(C, NegativeOne), Cont, Check);
420
421  EmitBlock(Check);
422  Builder.CreateCondBr(Builder.CreateICmpUGE(C,
423                                        llvm::ConstantInt::get(IntPtrTy, Size)),
424                       Cont, getTrapBB());
425  EmitBlock(Cont);
426}
427
428
429CodeGenFunction::ComplexPairTy CodeGenFunction::
430EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
431                         bool isInc, bool isPre) {
432  ComplexPairTy InVal = LoadComplexFromAddr(LV.getAddress(),
433                                            LV.isVolatileQualified());
434
435  llvm::Value *NextVal;
436  if (isa<llvm::IntegerType>(InVal.first->getType())) {
437    uint64_t AmountVal = isInc ? 1 : -1;
438    NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
439
440    // Add the inc/dec to the real part.
441    NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
442  } else {
443    QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
444    llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
445    if (!isInc)
446      FVal.changeSign();
447    NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
448
449    // Add the inc/dec to the real part.
450    NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
451  }
452
453  ComplexPairTy IncVal(NextVal, InVal.second);
454
455  // Store the updated result through the lvalue.
456  StoreComplexToAddr(IncVal, LV.getAddress(), LV.isVolatileQualified());
457
458  // If this is a postinc, return the value read from memory, otherwise use the
459  // updated value.
460  return isPre ? IncVal : InVal;
461}
462
463
464//===----------------------------------------------------------------------===//
465//                         LValue Expression Emission
466//===----------------------------------------------------------------------===//
467
468RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
469  if (Ty->isVoidType())
470    return RValue::get(0);
471
472  if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
473    const llvm::Type *EltTy = ConvertType(CTy->getElementType());
474    llvm::Value *U = llvm::UndefValue::get(EltTy);
475    return RValue::getComplex(std::make_pair(U, U));
476  }
477
478  // If this is a use of an undefined aggregate type, the aggregate must have an
479  // identifiable address.  Just because the contents of the value are undefined
480  // doesn't mean that the address can't be taken and compared.
481  if (hasAggregateLLVMType(Ty)) {
482    llvm::Value *DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
483    return RValue::getAggregate(DestPtr);
484  }
485
486  return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
487}
488
489RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
490                                              const char *Name) {
491  ErrorUnsupported(E, Name);
492  return GetUndefRValue(E->getType());
493}
494
495LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
496                                              const char *Name) {
497  ErrorUnsupported(E, Name);
498  llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
499  return MakeAddrLValue(llvm::UndefValue::get(Ty), E->getType());
500}
501
502LValue CodeGenFunction::EmitCheckedLValue(const Expr *E) {
503  LValue LV = EmitLValue(E);
504  if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple())
505    EmitCheck(LV.getAddress(),
506              getContext().getTypeSizeInChars(E->getType()).getQuantity());
507  return LV;
508}
509
510/// EmitLValue - Emit code to compute a designator that specifies the location
511/// of the expression.
512///
513/// This can return one of two things: a simple address or a bitfield reference.
514/// In either case, the LLVM Value* in the LValue structure is guaranteed to be
515/// an LLVM pointer type.
516///
517/// If this returns a bitfield reference, nothing about the pointee type of the
518/// LLVM value is known: For example, it may not be a pointer to an integer.
519///
520/// If this returns a normal address, and if the lvalue's C type is fixed size,
521/// this method guarantees that the returned pointer type will point to an LLVM
522/// type of the same size of the lvalue's type.  If the lvalue has a variable
523/// length type, this is not possible.
524///
525LValue CodeGenFunction::EmitLValue(const Expr *E) {
526  switch (E->getStmtClass()) {
527  default: return EmitUnsupportedLValue(E, "l-value expression");
528
529  case Expr::ObjCSelectorExprClass:
530  return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
531  case Expr::ObjCIsaExprClass:
532    return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
533  case Expr::BinaryOperatorClass:
534    return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
535  case Expr::CompoundAssignOperatorClass:
536    if (!E->getType()->isAnyComplexType())
537      return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
538    return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
539  case Expr::CallExprClass:
540  case Expr::CXXMemberCallExprClass:
541  case Expr::CXXOperatorCallExprClass:
542    return EmitCallExprLValue(cast<CallExpr>(E));
543  case Expr::VAArgExprClass:
544    return EmitVAArgExprLValue(cast<VAArgExpr>(E));
545  case Expr::DeclRefExprClass:
546    return EmitDeclRefLValue(cast<DeclRefExpr>(E));
547  case Expr::ParenExprClass:return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
548  case Expr::PredefinedExprClass:
549    return EmitPredefinedLValue(cast<PredefinedExpr>(E));
550  case Expr::StringLiteralClass:
551    return EmitStringLiteralLValue(cast<StringLiteral>(E));
552  case Expr::ObjCEncodeExprClass:
553    return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
554
555  case Expr::BlockDeclRefExprClass:
556    return EmitBlockDeclRefLValue(cast<BlockDeclRefExpr>(E));
557
558  case Expr::CXXTemporaryObjectExprClass:
559  case Expr::CXXConstructExprClass:
560    return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
561  case Expr::CXXBindTemporaryExprClass:
562    return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
563  case Expr::ExprWithCleanupsClass:
564    return EmitExprWithCleanupsLValue(cast<ExprWithCleanups>(E));
565  case Expr::CXXScalarValueInitExprClass:
566    return EmitNullInitializationLValue(cast<CXXScalarValueInitExpr>(E));
567  case Expr::CXXDefaultArgExprClass:
568    return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr());
569  case Expr::CXXTypeidExprClass:
570    return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
571
572  case Expr::ObjCMessageExprClass:
573    return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
574  case Expr::ObjCIvarRefExprClass:
575    return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
576  case Expr::ObjCPropertyRefExprClass:
577    return EmitObjCPropertyRefLValue(cast<ObjCPropertyRefExpr>(E));
578  case Expr::StmtExprClass:
579    return EmitStmtExprLValue(cast<StmtExpr>(E));
580  case Expr::UnaryOperatorClass:
581    return EmitUnaryOpLValue(cast<UnaryOperator>(E));
582  case Expr::ArraySubscriptExprClass:
583    return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
584  case Expr::ExtVectorElementExprClass:
585    return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
586  case Expr::MemberExprClass:
587    return EmitMemberExpr(cast<MemberExpr>(E));
588  case Expr::CompoundLiteralExprClass:
589    return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
590  case Expr::ConditionalOperatorClass:
591    return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
592  case Expr::BinaryConditionalOperatorClass:
593    return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
594  case Expr::ChooseExprClass:
595    return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(getContext()));
596  case Expr::OpaqueValueExprClass:
597    return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
598  case Expr::ImplicitCastExprClass:
599  case Expr::CStyleCastExprClass:
600  case Expr::CXXFunctionalCastExprClass:
601  case Expr::CXXStaticCastExprClass:
602  case Expr::CXXDynamicCastExprClass:
603  case Expr::CXXReinterpretCastExprClass:
604  case Expr::CXXConstCastExprClass:
605    return EmitCastLValue(cast<CastExpr>(E));
606  }
607}
608
609llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile,
610                                              unsigned Alignment, QualType Ty,
611                                              llvm::MDNode *TBAAInfo) {
612  llvm::LoadInst *Load = Builder.CreateLoad(Addr, "tmp");
613  if (Volatile)
614    Load->setVolatile(true);
615  if (Alignment)
616    Load->setAlignment(Alignment);
617  if (TBAAInfo)
618    CGM.DecorateInstruction(Load, TBAAInfo);
619
620  return EmitFromMemory(Load, Ty);
621}
622
623static bool isBooleanUnderlyingType(QualType Ty) {
624  if (const EnumType *ET = dyn_cast<EnumType>(Ty))
625    return ET->getDecl()->getIntegerType()->isBooleanType();
626  return false;
627}
628
629llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
630  // Bool has a different representation in memory than in registers.
631  if (Ty->isBooleanType() || isBooleanUnderlyingType(Ty)) {
632    // This should really always be an i1, but sometimes it's already
633    // an i8, and it's awkward to track those cases down.
634    if (Value->getType()->isIntegerTy(1))
635      return Builder.CreateZExt(Value, Builder.getInt8Ty(), "frombool");
636    assert(Value->getType()->isIntegerTy(8) && "value rep of bool not i1/i8");
637  }
638
639  return Value;
640}
641
642llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
643  // Bool has a different representation in memory than in registers.
644  if (Ty->isBooleanType() || isBooleanUnderlyingType(Ty)) {
645    assert(Value->getType()->isIntegerTy(8) && "memory rep of bool not i8");
646    return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool");
647  }
648
649  return Value;
650}
651
652void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr,
653                                        bool Volatile, unsigned Alignment,
654                                        QualType Ty,
655                                        llvm::MDNode *TBAAInfo) {
656  Value = EmitToMemory(Value, Ty);
657  llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
658  if (Alignment)
659    Store->setAlignment(Alignment);
660  if (TBAAInfo)
661    CGM.DecorateInstruction(Store, TBAAInfo);
662}
663
664/// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
665/// method emits the address of the lvalue, then loads the result as an rvalue,
666/// returning the rvalue.
667RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, QualType ExprType) {
668  if (LV.isObjCWeak()) {
669    // load of a __weak object.
670    llvm::Value *AddrWeakObj = LV.getAddress();
671    return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
672                                                             AddrWeakObj));
673  }
674
675  if (LV.isSimple()) {
676    llvm::Value *Ptr = LV.getAddress();
677
678    // Functions are l-values that don't require loading.
679    if (ExprType->isFunctionType())
680      return RValue::get(Ptr);
681
682    // Everything needs a load.
683    return RValue::get(EmitLoadOfScalar(Ptr, LV.isVolatileQualified(),
684                                        LV.getAlignment(), ExprType,
685                                        LV.getTBAAInfo()));
686
687  }
688
689  if (LV.isVectorElt()) {
690    llvm::Value *Vec = Builder.CreateLoad(LV.getVectorAddr(),
691                                          LV.isVolatileQualified(), "tmp");
692    return RValue::get(Builder.CreateExtractElement(Vec, LV.getVectorIdx(),
693                                                    "vecext"));
694  }
695
696  // If this is a reference to a subset of the elements of a vector, either
697  // shuffle the input or extract/insert them as appropriate.
698  if (LV.isExtVectorElt())
699    return EmitLoadOfExtVectorElementLValue(LV, ExprType);
700
701  if (LV.isBitField())
702    return EmitLoadOfBitfieldLValue(LV, ExprType);
703
704  assert(LV.isPropertyRef() && "Unknown LValue type!");
705  return EmitLoadOfPropertyRefLValue(LV);
706}
707
708RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
709                                                 QualType ExprType) {
710  const CGBitFieldInfo &Info = LV.getBitFieldInfo();
711
712  // Get the output type.
713  const llvm::Type *ResLTy = ConvertType(ExprType);
714  unsigned ResSizeInBits = CGM.getTargetData().getTypeSizeInBits(ResLTy);
715
716  // Compute the result as an OR of all of the individual component accesses.
717  llvm::Value *Res = 0;
718  for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) {
719    const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i);
720
721    // Get the field pointer.
722    llvm::Value *Ptr = LV.getBitFieldBaseAddr();
723
724    // Only offset by the field index if used, so that incoming values are not
725    // required to be structures.
726    if (AI.FieldIndex)
727      Ptr = Builder.CreateStructGEP(Ptr, AI.FieldIndex, "bf.field");
728
729    // Offset by the byte offset, if used.
730    if (AI.FieldByteOffset) {
731      Ptr = EmitCastToVoidPtr(Ptr);
732      Ptr = Builder.CreateConstGEP1_32(Ptr, AI.FieldByteOffset,"bf.field.offs");
733    }
734
735    // Cast to the access type.
736    const llvm::Type *PTy = llvm::Type::getIntNPtrTy(getLLVMContext(),
737                                                     AI.AccessWidth,
738                              CGM.getContext().getTargetAddressSpace(ExprType));
739    Ptr = Builder.CreateBitCast(Ptr, PTy);
740
741    // Perform the load.
742    llvm::LoadInst *Load = Builder.CreateLoad(Ptr, LV.isVolatileQualified());
743    if (AI.AccessAlignment)
744      Load->setAlignment(AI.AccessAlignment);
745
746    // Shift out unused low bits and mask out unused high bits.
747    llvm::Value *Val = Load;
748    if (AI.FieldBitStart)
749      Val = Builder.CreateLShr(Load, AI.FieldBitStart);
750    Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(AI.AccessWidth,
751                                                            AI.TargetBitWidth),
752                            "bf.clear");
753
754    // Extend or truncate to the target size.
755    if (AI.AccessWidth < ResSizeInBits)
756      Val = Builder.CreateZExt(Val, ResLTy);
757    else if (AI.AccessWidth > ResSizeInBits)
758      Val = Builder.CreateTrunc(Val, ResLTy);
759
760    // Shift into place, and OR into the result.
761    if (AI.TargetBitOffset)
762      Val = Builder.CreateShl(Val, AI.TargetBitOffset);
763    Res = Res ? Builder.CreateOr(Res, Val) : Val;
764  }
765
766  // If the bit-field is signed, perform the sign-extension.
767  //
768  // FIXME: This can easily be folded into the load of the high bits, which
769  // could also eliminate the mask of high bits in some situations.
770  if (Info.isSigned()) {
771    unsigned ExtraBits = ResSizeInBits - Info.getSize();
772    if (ExtraBits)
773      Res = Builder.CreateAShr(Builder.CreateShl(Res, ExtraBits),
774                               ExtraBits, "bf.val.sext");
775  }
776
777  return RValue::get(Res);
778}
779
780// If this is a reference to a subset of the elements of a vector, create an
781// appropriate shufflevector.
782RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV,
783                                                         QualType ExprType) {
784  llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddr(),
785                                        LV.isVolatileQualified(), "tmp");
786
787  const llvm::Constant *Elts = LV.getExtVectorElts();
788
789  // If the result of the expression is a non-vector type, we must be extracting
790  // a single element.  Just codegen as an extractelement.
791  const VectorType *ExprVT = ExprType->getAs<VectorType>();
792  if (!ExprVT) {
793    unsigned InIdx = getAccessedFieldNo(0, Elts);
794    llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx);
795    return RValue::get(Builder.CreateExtractElement(Vec, Elt, "tmp"));
796  }
797
798  // Always use shuffle vector to try to retain the original program structure
799  unsigned NumResultElts = ExprVT->getNumElements();
800
801  llvm::SmallVector<llvm::Constant*, 4> Mask;
802  for (unsigned i = 0; i != NumResultElts; ++i) {
803    unsigned InIdx = getAccessedFieldNo(i, Elts);
804    Mask.push_back(llvm::ConstantInt::get(Int32Ty, InIdx));
805  }
806
807  llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
808  Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()),
809                                    MaskV, "tmp");
810  return RValue::get(Vec);
811}
812
813
814
815/// EmitStoreThroughLValue - Store the specified rvalue into the specified
816/// lvalue, where both are guaranteed to the have the same type, and that type
817/// is 'Ty'.
818void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
819                                             QualType Ty) {
820  if (!Dst.isSimple()) {
821    if (Dst.isVectorElt()) {
822      // Read/modify/write the vector, inserting the new element.
823      llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddr(),
824                                            Dst.isVolatileQualified(), "tmp");
825      Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
826                                        Dst.getVectorIdx(), "vecins");
827      Builder.CreateStore(Vec, Dst.getVectorAddr(),Dst.isVolatileQualified());
828      return;
829    }
830
831    // If this is an update of extended vector elements, insert them as
832    // appropriate.
833    if (Dst.isExtVectorElt())
834      return EmitStoreThroughExtVectorComponentLValue(Src, Dst, Ty);
835
836    if (Dst.isBitField())
837      return EmitStoreThroughBitfieldLValue(Src, Dst, Ty);
838
839    assert(Dst.isPropertyRef() && "Unknown LValue type");
840    return EmitStoreThroughPropertyRefLValue(Src, Dst);
841  }
842
843  if (Dst.isObjCWeak() && !Dst.isNonGC()) {
844    // load of a __weak object.
845    llvm::Value *LvalueDst = Dst.getAddress();
846    llvm::Value *src = Src.getScalarVal();
847     CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
848    return;
849  }
850
851  if (Dst.isObjCStrong() && !Dst.isNonGC()) {
852    // load of a __strong object.
853    llvm::Value *LvalueDst = Dst.getAddress();
854    llvm::Value *src = Src.getScalarVal();
855    if (Dst.isObjCIvar()) {
856      assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
857      const llvm::Type *ResultType = ConvertType(getContext().LongTy);
858      llvm::Value *RHS = EmitScalarExpr(Dst.getBaseIvarExp());
859      llvm::Value *dst = RHS;
860      RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
861      llvm::Value *LHS =
862        Builder.CreatePtrToInt(LvalueDst, ResultType, "sub.ptr.lhs.cast");
863      llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
864      CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
865                                              BytesBetween);
866    } else if (Dst.isGlobalObjCRef()) {
867      CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
868                                                Dst.isThreadLocalRef());
869    }
870    else
871      CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
872    return;
873  }
874
875  assert(Src.isScalar() && "Can't emit an agg store with this method");
876  EmitStoreOfScalar(Src.getScalarVal(), Dst.getAddress(),
877                    Dst.isVolatileQualified(), Dst.getAlignment(), Ty,
878                    Dst.getTBAAInfo());
879}
880
881void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
882                                                     QualType Ty,
883                                                     llvm::Value **Result) {
884  const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
885
886  // Get the output type.
887  const llvm::Type *ResLTy = ConvertTypeForMem(Ty);
888  unsigned ResSizeInBits = CGM.getTargetData().getTypeSizeInBits(ResLTy);
889
890  // Get the source value, truncated to the width of the bit-field.
891  llvm::Value *SrcVal = Src.getScalarVal();
892
893  if (Ty->isBooleanType())
894    SrcVal = Builder.CreateIntCast(SrcVal, ResLTy, /*IsSigned=*/false);
895
896  SrcVal = Builder.CreateAnd(SrcVal, llvm::APInt::getLowBitsSet(ResSizeInBits,
897                                                                Info.getSize()),
898                             "bf.value");
899
900  // Return the new value of the bit-field, if requested.
901  if (Result) {
902    // Cast back to the proper type for result.
903    const llvm::Type *SrcTy = Src.getScalarVal()->getType();
904    llvm::Value *ReloadVal = Builder.CreateIntCast(SrcVal, SrcTy, false,
905                                                   "bf.reload.val");
906
907    // Sign extend if necessary.
908    if (Info.isSigned()) {
909      unsigned ExtraBits = ResSizeInBits - Info.getSize();
910      if (ExtraBits)
911        ReloadVal = Builder.CreateAShr(Builder.CreateShl(ReloadVal, ExtraBits),
912                                       ExtraBits, "bf.reload.sext");
913    }
914
915    *Result = ReloadVal;
916  }
917
918  // Iterate over the components, writing each piece to memory.
919  for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) {
920    const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i);
921
922    // Get the field pointer.
923    llvm::Value *Ptr = Dst.getBitFieldBaseAddr();
924    unsigned addressSpace =
925      cast<llvm::PointerType>(Ptr->getType())->getAddressSpace();
926
927    // Only offset by the field index if used, so that incoming values are not
928    // required to be structures.
929    if (AI.FieldIndex)
930      Ptr = Builder.CreateStructGEP(Ptr, AI.FieldIndex, "bf.field");
931
932    // Offset by the byte offset, if used.
933    if (AI.FieldByteOffset) {
934      Ptr = EmitCastToVoidPtr(Ptr);
935      Ptr = Builder.CreateConstGEP1_32(Ptr, AI.FieldByteOffset,"bf.field.offs");
936    }
937
938    // Cast to the access type.
939    const llvm::Type *AccessLTy =
940      llvm::Type::getIntNTy(getLLVMContext(), AI.AccessWidth);
941
942    const llvm::Type *PTy = AccessLTy->getPointerTo(addressSpace);
943    Ptr = Builder.CreateBitCast(Ptr, PTy);
944
945    // Extract the piece of the bit-field value to write in this access, limited
946    // to the values that are part of this access.
947    llvm::Value *Val = SrcVal;
948    if (AI.TargetBitOffset)
949      Val = Builder.CreateLShr(Val, AI.TargetBitOffset);
950    Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(ResSizeInBits,
951                                                            AI.TargetBitWidth));
952
953    // Extend or truncate to the access size.
954    if (ResSizeInBits < AI.AccessWidth)
955      Val = Builder.CreateZExt(Val, AccessLTy);
956    else if (ResSizeInBits > AI.AccessWidth)
957      Val = Builder.CreateTrunc(Val, AccessLTy);
958
959    // Shift into the position in memory.
960    if (AI.FieldBitStart)
961      Val = Builder.CreateShl(Val, AI.FieldBitStart);
962
963    // If necessary, load and OR in bits that are outside of the bit-field.
964    if (AI.TargetBitWidth != AI.AccessWidth) {
965      llvm::LoadInst *Load = Builder.CreateLoad(Ptr, Dst.isVolatileQualified());
966      if (AI.AccessAlignment)
967        Load->setAlignment(AI.AccessAlignment);
968
969      // Compute the mask for zeroing the bits that are part of the bit-field.
970      llvm::APInt InvMask =
971        ~llvm::APInt::getBitsSet(AI.AccessWidth, AI.FieldBitStart,
972                                 AI.FieldBitStart + AI.TargetBitWidth);
973
974      // Apply the mask and OR in to the value to write.
975      Val = Builder.CreateOr(Builder.CreateAnd(Load, InvMask), Val);
976    }
977
978    // Write the value.
979    llvm::StoreInst *Store = Builder.CreateStore(Val, Ptr,
980                                                 Dst.isVolatileQualified());
981    if (AI.AccessAlignment)
982      Store->setAlignment(AI.AccessAlignment);
983  }
984}
985
986void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
987                                                               LValue Dst,
988                                                               QualType Ty) {
989  // This access turns into a read/modify/write of the vector.  Load the input
990  // value now.
991  llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddr(),
992                                        Dst.isVolatileQualified(), "tmp");
993  const llvm::Constant *Elts = Dst.getExtVectorElts();
994
995  llvm::Value *SrcVal = Src.getScalarVal();
996
997  if (const VectorType *VTy = Ty->getAs<VectorType>()) {
998    unsigned NumSrcElts = VTy->getNumElements();
999    unsigned NumDstElts =
1000       cast<llvm::VectorType>(Vec->getType())->getNumElements();
1001    if (NumDstElts == NumSrcElts) {
1002      // Use shuffle vector is the src and destination are the same number of
1003      // elements and restore the vector mask since it is on the side it will be
1004      // stored.
1005      llvm::SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
1006      for (unsigned i = 0; i != NumSrcElts; ++i) {
1007        unsigned InIdx = getAccessedFieldNo(i, Elts);
1008        Mask[InIdx] = llvm::ConstantInt::get(Int32Ty, i);
1009      }
1010
1011      llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1012      Vec = Builder.CreateShuffleVector(SrcVal,
1013                                        llvm::UndefValue::get(Vec->getType()),
1014                                        MaskV, "tmp");
1015    } else if (NumDstElts > NumSrcElts) {
1016      // Extended the source vector to the same length and then shuffle it
1017      // into the destination.
1018      // FIXME: since we're shuffling with undef, can we just use the indices
1019      //        into that?  This could be simpler.
1020      llvm::SmallVector<llvm::Constant*, 4> ExtMask;
1021      unsigned i;
1022      for (i = 0; i != NumSrcElts; ++i)
1023        ExtMask.push_back(llvm::ConstantInt::get(Int32Ty, i));
1024      for (; i != NumDstElts; ++i)
1025        ExtMask.push_back(llvm::UndefValue::get(Int32Ty));
1026      llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask);
1027      llvm::Value *ExtSrcVal =
1028        Builder.CreateShuffleVector(SrcVal,
1029                                    llvm::UndefValue::get(SrcVal->getType()),
1030                                    ExtMaskV, "tmp");
1031      // build identity
1032      llvm::SmallVector<llvm::Constant*, 4> Mask;
1033      for (unsigned i = 0; i != NumDstElts; ++i)
1034        Mask.push_back(llvm::ConstantInt::get(Int32Ty, i));
1035
1036      // modify when what gets shuffled in
1037      for (unsigned i = 0; i != NumSrcElts; ++i) {
1038        unsigned Idx = getAccessedFieldNo(i, Elts);
1039        Mask[Idx] = llvm::ConstantInt::get(Int32Ty, i+NumDstElts);
1040      }
1041      llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1042      Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV, "tmp");
1043    } else {
1044      // We should never shorten the vector
1045      assert(0 && "unexpected shorten vector length");
1046    }
1047  } else {
1048    // If the Src is a scalar (not a vector) it must be updating one element.
1049    unsigned InIdx = getAccessedFieldNo(0, Elts);
1050    llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx);
1051    Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt, "tmp");
1052  }
1053
1054  Builder.CreateStore(Vec, Dst.getExtVectorAddr(), Dst.isVolatileQualified());
1055}
1056
1057// setObjCGCLValueClass - sets class of he lvalue for the purpose of
1058// generating write-barries API. It is currently a global, ivar,
1059// or neither.
1060static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
1061                                 LValue &LV) {
1062  if (Ctx.getLangOptions().getGCMode() == LangOptions::NonGC)
1063    return;
1064
1065  if (isa<ObjCIvarRefExpr>(E)) {
1066    LV.setObjCIvar(true);
1067    ObjCIvarRefExpr *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr*>(E));
1068    LV.setBaseIvarExp(Exp->getBase());
1069    LV.setObjCArray(E->getType()->isArrayType());
1070    return;
1071  }
1072
1073  if (const DeclRefExpr *Exp = dyn_cast<DeclRefExpr>(E)) {
1074    if (const VarDecl *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
1075      if (VD->hasGlobalStorage()) {
1076        LV.setGlobalObjCRef(true);
1077        LV.setThreadLocalRef(VD->isThreadSpecified());
1078      }
1079    }
1080    LV.setObjCArray(E->getType()->isArrayType());
1081    return;
1082  }
1083
1084  if (const UnaryOperator *Exp = dyn_cast<UnaryOperator>(E)) {
1085    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1086    return;
1087  }
1088
1089  if (const ParenExpr *Exp = dyn_cast<ParenExpr>(E)) {
1090    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1091    if (LV.isObjCIvar()) {
1092      // If cast is to a structure pointer, follow gcc's behavior and make it
1093      // a non-ivar write-barrier.
1094      QualType ExpTy = E->getType();
1095      if (ExpTy->isPointerType())
1096        ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
1097      if (ExpTy->isRecordType())
1098        LV.setObjCIvar(false);
1099    }
1100    return;
1101  }
1102  if (const ImplicitCastExpr *Exp = dyn_cast<ImplicitCastExpr>(E)) {
1103    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1104    return;
1105  }
1106
1107  if (const CStyleCastExpr *Exp = dyn_cast<CStyleCastExpr>(E)) {
1108    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1109    return;
1110  }
1111
1112  if (const ArraySubscriptExpr *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
1113    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
1114    if (LV.isObjCIvar() && !LV.isObjCArray())
1115      // Using array syntax to assigning to what an ivar points to is not
1116      // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
1117      LV.setObjCIvar(false);
1118    else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
1119      // Using array syntax to assigning to what global points to is not
1120      // same as assigning to the global itself. {id *G;} G[i] = 0;
1121      LV.setGlobalObjCRef(false);
1122    return;
1123  }
1124
1125  if (const MemberExpr *Exp = dyn_cast<MemberExpr>(E)) {
1126    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
1127    // We don't know if member is an 'ivar', but this flag is looked at
1128    // only in the context of LV.isObjCIvar().
1129    LV.setObjCArray(E->getType()->isArrayType());
1130    return;
1131  }
1132}
1133
1134static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
1135                                      const Expr *E, const VarDecl *VD) {
1136  assert((VD->hasExternalStorage() || VD->isFileVarDecl()) &&
1137         "Var decl must have external storage or be a file var decl!");
1138
1139  llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
1140  if (VD->getType()->isReferenceType())
1141    V = CGF.Builder.CreateLoad(V, "tmp");
1142  unsigned Alignment = CGF.getContext().getDeclAlign(VD).getQuantity();
1143  LValue LV = CGF.MakeAddrLValue(V, E->getType(), Alignment);
1144  setObjCGCLValueClass(CGF.getContext(), E, LV);
1145  return LV;
1146}
1147
1148static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
1149                                      const Expr *E, const FunctionDecl *FD) {
1150  llvm::Value *V = CGF.CGM.GetAddrOfFunction(FD);
1151  if (!FD->hasPrototype()) {
1152    if (const FunctionProtoType *Proto =
1153            FD->getType()->getAs<FunctionProtoType>()) {
1154      // Ugly case: for a K&R-style definition, the type of the definition
1155      // isn't the same as the type of a use.  Correct for this with a
1156      // bitcast.
1157      QualType NoProtoType =
1158          CGF.getContext().getFunctionNoProtoType(Proto->getResultType());
1159      NoProtoType = CGF.getContext().getPointerType(NoProtoType);
1160      V = CGF.Builder.CreateBitCast(V, CGF.ConvertType(NoProtoType), "tmp");
1161    }
1162  }
1163  unsigned Alignment = CGF.getContext().getDeclAlign(FD).getQuantity();
1164  return CGF.MakeAddrLValue(V, E->getType(), Alignment);
1165}
1166
1167LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
1168  const NamedDecl *ND = E->getDecl();
1169  unsigned Alignment = getContext().getDeclAlign(ND).getQuantity();
1170
1171  if (ND->hasAttr<WeakRefAttr>()) {
1172    const ValueDecl *VD = cast<ValueDecl>(ND);
1173    llvm::Constant *Aliasee = CGM.GetWeakRefReference(VD);
1174    return MakeAddrLValue(Aliasee, E->getType(), Alignment);
1175  }
1176
1177  if (const VarDecl *VD = dyn_cast<VarDecl>(ND)) {
1178
1179    // Check if this is a global variable.
1180    if (VD->hasExternalStorage() || VD->isFileVarDecl())
1181      return EmitGlobalVarDeclLValue(*this, E, VD);
1182
1183    bool NonGCable = VD->hasLocalStorage() &&
1184                     !VD->getType()->isReferenceType() &&
1185                     !VD->hasAttr<BlocksAttr>();
1186
1187    llvm::Value *V = LocalDeclMap[VD];
1188    if (!V && VD->isStaticLocal())
1189      V = CGM.getStaticLocalDeclAddress(VD);
1190    assert(V && "DeclRefExpr not entered in LocalDeclMap?");
1191
1192    if (VD->hasAttr<BlocksAttr>())
1193      V = BuildBlockByrefAddress(V, VD);
1194
1195    if (VD->getType()->isReferenceType())
1196      V = Builder.CreateLoad(V, "tmp");
1197
1198    LValue LV = MakeAddrLValue(V, E->getType(), Alignment);
1199    if (NonGCable) {
1200      LV.getQuals().removeObjCGCAttr();
1201      LV.setNonGC(true);
1202    }
1203    setObjCGCLValueClass(getContext(), E, LV);
1204    return LV;
1205  }
1206
1207  if (const FunctionDecl *fn = dyn_cast<FunctionDecl>(ND))
1208    return EmitFunctionDeclLValue(*this, E, fn);
1209
1210  assert(false && "Unhandled DeclRefExpr");
1211
1212  // an invalid LValue, but the assert will
1213  // ensure that this point is never reached.
1214  return LValue();
1215}
1216
1217LValue CodeGenFunction::EmitBlockDeclRefLValue(const BlockDeclRefExpr *E) {
1218  unsigned Alignment =
1219    getContext().getDeclAlign(E->getDecl()).getQuantity();
1220  return MakeAddrLValue(GetAddrOfBlockDecl(E), E->getType(), Alignment);
1221}
1222
1223LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
1224  // __extension__ doesn't affect lvalue-ness.
1225  if (E->getOpcode() == UO_Extension)
1226    return EmitLValue(E->getSubExpr());
1227
1228  QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
1229  switch (E->getOpcode()) {
1230  default: assert(0 && "Unknown unary operator lvalue!");
1231  case UO_Deref: {
1232    QualType T = E->getSubExpr()->getType()->getPointeeType();
1233    assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
1234
1235    LValue LV = MakeAddrLValue(EmitScalarExpr(E->getSubExpr()), T);
1236    LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
1237
1238    // We should not generate __weak write barrier on indirect reference
1239    // of a pointer to object; as in void foo (__weak id *param); *param = 0;
1240    // But, we continue to generate __strong write barrier on indirect write
1241    // into a pointer to object.
1242    if (getContext().getLangOptions().ObjC1 &&
1243        getContext().getLangOptions().getGCMode() != LangOptions::NonGC &&
1244        LV.isObjCWeak())
1245      LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
1246    return LV;
1247  }
1248  case UO_Real:
1249  case UO_Imag: {
1250    LValue LV = EmitLValue(E->getSubExpr());
1251    assert(LV.isSimple() && "real/imag on non-ordinary l-value");
1252    llvm::Value *Addr = LV.getAddress();
1253
1254    // real and imag are valid on scalars.  This is a faster way of
1255    // testing that.
1256    if (!cast<llvm::PointerType>(Addr->getType())
1257           ->getElementType()->isStructTy()) {
1258      assert(E->getSubExpr()->getType()->isArithmeticType());
1259      return LV;
1260    }
1261
1262    assert(E->getSubExpr()->getType()->isAnyComplexType());
1263
1264    unsigned Idx = E->getOpcode() == UO_Imag;
1265    return MakeAddrLValue(Builder.CreateStructGEP(LV.getAddress(),
1266                                                  Idx, "idx"),
1267                          ExprTy);
1268  }
1269  case UO_PreInc:
1270  case UO_PreDec: {
1271    LValue LV = EmitLValue(E->getSubExpr());
1272    bool isInc = E->getOpcode() == UO_PreInc;
1273
1274    if (E->getType()->isAnyComplexType())
1275      EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
1276    else
1277      EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
1278    return LV;
1279  }
1280  }
1281}
1282
1283LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
1284  return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
1285                        E->getType());
1286}
1287
1288LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
1289  return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
1290                        E->getType());
1291}
1292
1293
1294LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
1295  switch (E->getIdentType()) {
1296  default:
1297    return EmitUnsupportedLValue(E, "predefined expression");
1298
1299  case PredefinedExpr::Func:
1300  case PredefinedExpr::Function:
1301  case PredefinedExpr::PrettyFunction: {
1302    unsigned Type = E->getIdentType();
1303    std::string GlobalVarName;
1304
1305    switch (Type) {
1306    default: assert(0 && "Invalid type");
1307    case PredefinedExpr::Func:
1308      GlobalVarName = "__func__.";
1309      break;
1310    case PredefinedExpr::Function:
1311      GlobalVarName = "__FUNCTION__.";
1312      break;
1313    case PredefinedExpr::PrettyFunction:
1314      GlobalVarName = "__PRETTY_FUNCTION__.";
1315      break;
1316    }
1317
1318    llvm::StringRef FnName = CurFn->getName();
1319    if (FnName.startswith("\01"))
1320      FnName = FnName.substr(1);
1321    GlobalVarName += FnName;
1322
1323    const Decl *CurDecl = CurCodeDecl;
1324    if (CurDecl == 0)
1325      CurDecl = getContext().getTranslationUnitDecl();
1326
1327    std::string FunctionName =
1328        (isa<BlockDecl>(CurDecl)
1329         ? FnName.str()
1330         : PredefinedExpr::ComputeName((PredefinedExpr::IdentType)Type, CurDecl));
1331
1332    llvm::Constant *C =
1333      CGM.GetAddrOfConstantCString(FunctionName, GlobalVarName.c_str());
1334    return MakeAddrLValue(C, E->getType());
1335  }
1336  }
1337}
1338
1339llvm::BasicBlock *CodeGenFunction::getTrapBB() {
1340  const CodeGenOptions &GCO = CGM.getCodeGenOpts();
1341
1342  // If we are not optimzing, don't collapse all calls to trap in the function
1343  // to the same call, that way, in the debugger they can see which operation
1344  // did in fact fail.  If we are optimizing, we collapse all calls to trap down
1345  // to just one per function to save on codesize.
1346  if (GCO.OptimizationLevel && TrapBB)
1347    return TrapBB;
1348
1349  llvm::BasicBlock *Cont = 0;
1350  if (HaveInsertPoint()) {
1351    Cont = createBasicBlock("cont");
1352    EmitBranch(Cont);
1353  }
1354  TrapBB = createBasicBlock("trap");
1355  EmitBlock(TrapBB);
1356
1357  llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::trap, 0, 0);
1358  llvm::CallInst *TrapCall = Builder.CreateCall(F);
1359  TrapCall->setDoesNotReturn();
1360  TrapCall->setDoesNotThrow();
1361  Builder.CreateUnreachable();
1362
1363  if (Cont)
1364    EmitBlock(Cont);
1365  return TrapBB;
1366}
1367
1368/// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
1369/// array to pointer, return the array subexpression.
1370static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
1371  // If this isn't just an array->pointer decay, bail out.
1372  const CastExpr *CE = dyn_cast<CastExpr>(E);
1373  if (CE == 0 || CE->getCastKind() != CK_ArrayToPointerDecay)
1374    return 0;
1375
1376  // If this is a decay from variable width array, bail out.
1377  const Expr *SubExpr = CE->getSubExpr();
1378  if (SubExpr->getType()->isVariableArrayType())
1379    return 0;
1380
1381  return SubExpr;
1382}
1383
1384LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E) {
1385  // The index must always be an integer, which is not an aggregate.  Emit it.
1386  llvm::Value *Idx = EmitScalarExpr(E->getIdx());
1387  QualType IdxTy  = E->getIdx()->getType();
1388  bool IdxSigned = IdxTy->isSignedIntegerType();
1389
1390  // If the base is a vector type, then we are forming a vector element lvalue
1391  // with this subscript.
1392  if (E->getBase()->getType()->isVectorType()) {
1393    // Emit the vector as an lvalue to get its address.
1394    LValue LHS = EmitLValue(E->getBase());
1395    assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
1396    Idx = Builder.CreateIntCast(Idx, Int32Ty, IdxSigned, "vidx");
1397    return LValue::MakeVectorElt(LHS.getAddress(), Idx,
1398                                 E->getBase()->getType().getCVRQualifiers());
1399  }
1400
1401  // Extend or truncate the index type to 32 or 64-bits.
1402  if (Idx->getType() != IntPtrTy)
1403    Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
1404
1405  // FIXME: As llvm implements the object size checking, this can come out.
1406  if (CatchUndefined) {
1407    if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E->getBase())){
1408      if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr())) {
1409        if (ICE->getCastKind() == CK_ArrayToPointerDecay) {
1410          if (const ConstantArrayType *CAT
1411              = getContext().getAsConstantArrayType(DRE->getType())) {
1412            llvm::APInt Size = CAT->getSize();
1413            llvm::BasicBlock *Cont = createBasicBlock("cont");
1414            Builder.CreateCondBr(Builder.CreateICmpULE(Idx,
1415                                  llvm::ConstantInt::get(Idx->getType(), Size)),
1416                                 Cont, getTrapBB());
1417            EmitBlock(Cont);
1418          }
1419        }
1420      }
1421    }
1422  }
1423
1424  // We know that the pointer points to a type of the correct size, unless the
1425  // size is a VLA or Objective-C interface.
1426  llvm::Value *Address = 0;
1427  unsigned ArrayAlignment = 0;
1428  if (const VariableArrayType *VAT =
1429        getContext().getAsVariableArrayType(E->getType())) {
1430    llvm::Value *VLASize = GetVLASize(VAT);
1431
1432    Idx = Builder.CreateMul(Idx, VLASize);
1433
1434    // The base must be a pointer, which is not an aggregate.  Emit it.
1435    llvm::Value *Base = EmitScalarExpr(E->getBase());
1436
1437    Address = EmitCastToVoidPtr(Base);
1438    if (getContext().getLangOptions().isSignedOverflowDefined())
1439      Address = Builder.CreateGEP(Address, Idx, "arrayidx");
1440    else
1441      Address = Builder.CreateInBoundsGEP(Address, Idx, "arrayidx");
1442    Address = Builder.CreateBitCast(Address, Base->getType());
1443  } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
1444    // Indexing over an interface, as in "NSString *P; P[4];"
1445    llvm::Value *InterfaceSize =
1446      llvm::ConstantInt::get(Idx->getType(),
1447          getContext().getTypeSizeInChars(OIT).getQuantity());
1448
1449    Idx = Builder.CreateMul(Idx, InterfaceSize);
1450
1451    // The base must be a pointer, which is not an aggregate.  Emit it.
1452    llvm::Value *Base = EmitScalarExpr(E->getBase());
1453    Address = EmitCastToVoidPtr(Base);
1454    Address = Builder.CreateGEP(Address, Idx, "arrayidx");
1455    Address = Builder.CreateBitCast(Address, Base->getType());
1456  } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
1457    // If this is A[i] where A is an array, the frontend will have decayed the
1458    // base to be a ArrayToPointerDecay implicit cast.  While correct, it is
1459    // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
1460    // "gep x, i" here.  Emit one "gep A, 0, i".
1461    assert(Array->getType()->isArrayType() &&
1462           "Array to pointer decay must have array source type!");
1463    LValue ArrayLV = EmitLValue(Array);
1464    llvm::Value *ArrayPtr = ArrayLV.getAddress();
1465    llvm::Value *Zero = llvm::ConstantInt::get(Int32Ty, 0);
1466    llvm::Value *Args[] = { Zero, Idx };
1467
1468    // Propagate the alignment from the array itself to the result.
1469    ArrayAlignment = ArrayLV.getAlignment();
1470
1471    if (getContext().getLangOptions().isSignedOverflowDefined())
1472      Address = Builder.CreateGEP(ArrayPtr, Args, Args+2, "arrayidx");
1473    else
1474      Address = Builder.CreateInBoundsGEP(ArrayPtr, Args, Args+2, "arrayidx");
1475  } else {
1476    // The base must be a pointer, which is not an aggregate.  Emit it.
1477    llvm::Value *Base = EmitScalarExpr(E->getBase());
1478    if (getContext().getLangOptions().isSignedOverflowDefined())
1479      Address = Builder.CreateGEP(Base, Idx, "arrayidx");
1480    else
1481      Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
1482  }
1483
1484  QualType T = E->getBase()->getType()->getPointeeType();
1485  assert(!T.isNull() &&
1486         "CodeGenFunction::EmitArraySubscriptExpr(): Illegal base type");
1487
1488  LValue LV = MakeAddrLValue(Address, T, ArrayAlignment);
1489  LV.getQuals().setAddressSpace(E->getBase()->getType().getAddressSpace());
1490
1491  if (getContext().getLangOptions().ObjC1 &&
1492      getContext().getLangOptions().getGCMode() != LangOptions::NonGC) {
1493    LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
1494    setObjCGCLValueClass(getContext(), E, LV);
1495  }
1496  return LV;
1497}
1498
1499static
1500llvm::Constant *GenerateConstantVector(llvm::LLVMContext &VMContext,
1501                                       llvm::SmallVector<unsigned, 4> &Elts) {
1502  llvm::SmallVector<llvm::Constant*, 4> CElts;
1503
1504  const llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext);
1505  for (unsigned i = 0, e = Elts.size(); i != e; ++i)
1506    CElts.push_back(llvm::ConstantInt::get(Int32Ty, Elts[i]));
1507
1508  return llvm::ConstantVector::get(CElts);
1509}
1510
1511LValue CodeGenFunction::
1512EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
1513  // Emit the base vector as an l-value.
1514  LValue Base;
1515
1516  // ExtVectorElementExpr's base can either be a vector or pointer to vector.
1517  if (E->isArrow()) {
1518    // If it is a pointer to a vector, emit the address and form an lvalue with
1519    // it.
1520    llvm::Value *Ptr = EmitScalarExpr(E->getBase());
1521    const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
1522    Base = MakeAddrLValue(Ptr, PT->getPointeeType());
1523    Base.getQuals().removeObjCGCAttr();
1524  } else if (E->getBase()->isGLValue()) {
1525    // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
1526    // emit the base as an lvalue.
1527    assert(E->getBase()->getType()->isVectorType());
1528    Base = EmitLValue(E->getBase());
1529  } else {
1530    // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
1531    assert(E->getBase()->getType()->getAs<VectorType>() &&
1532           "Result must be a vector");
1533    llvm::Value *Vec = EmitScalarExpr(E->getBase());
1534
1535    // Store the vector to memory (because LValue wants an address).
1536    llvm::Value *VecMem = CreateMemTemp(E->getBase()->getType());
1537    Builder.CreateStore(Vec, VecMem);
1538    Base = MakeAddrLValue(VecMem, E->getBase()->getType());
1539  }
1540
1541  // Encode the element access list into a vector of unsigned indices.
1542  llvm::SmallVector<unsigned, 4> Indices;
1543  E->getEncodedElementAccess(Indices);
1544
1545  if (Base.isSimple()) {
1546    llvm::Constant *CV = GenerateConstantVector(getLLVMContext(), Indices);
1547    return LValue::MakeExtVectorElt(Base.getAddress(), CV,
1548                                    Base.getVRQualifiers());
1549  }
1550  assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
1551
1552  llvm::Constant *BaseElts = Base.getExtVectorElts();
1553  llvm::SmallVector<llvm::Constant *, 4> CElts;
1554
1555  for (unsigned i = 0, e = Indices.size(); i != e; ++i) {
1556    if (isa<llvm::ConstantAggregateZero>(BaseElts))
1557      CElts.push_back(llvm::ConstantInt::get(Int32Ty, 0));
1558    else
1559      CElts.push_back(cast<llvm::Constant>(BaseElts->getOperand(Indices[i])));
1560  }
1561  llvm::Constant *CV = llvm::ConstantVector::get(CElts);
1562  return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV,
1563                                  Base.getVRQualifiers());
1564}
1565
1566LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
1567  bool isNonGC = false;
1568  Expr *BaseExpr = E->getBase();
1569  llvm::Value *BaseValue = NULL;
1570  Qualifiers BaseQuals;
1571
1572  // If this is s.x, emit s as an lvalue.  If it is s->x, emit s as a scalar.
1573  if (E->isArrow()) {
1574    BaseValue = EmitScalarExpr(BaseExpr);
1575    const PointerType *PTy =
1576      BaseExpr->getType()->getAs<PointerType>();
1577    BaseQuals = PTy->getPointeeType().getQualifiers();
1578  } else {
1579    LValue BaseLV = EmitLValue(BaseExpr);
1580    if (BaseLV.isNonGC())
1581      isNonGC = true;
1582    // FIXME: this isn't right for bitfields.
1583    BaseValue = BaseLV.getAddress();
1584    QualType BaseTy = BaseExpr->getType();
1585    BaseQuals = BaseTy.getQualifiers();
1586  }
1587
1588  NamedDecl *ND = E->getMemberDecl();
1589  if (FieldDecl *Field = dyn_cast<FieldDecl>(ND)) {
1590    LValue LV = EmitLValueForField(BaseValue, Field,
1591                                   BaseQuals.getCVRQualifiers());
1592    LV.setNonGC(isNonGC);
1593    setObjCGCLValueClass(getContext(), E, LV);
1594    return LV;
1595  }
1596
1597  if (VarDecl *VD = dyn_cast<VarDecl>(ND))
1598    return EmitGlobalVarDeclLValue(*this, E, VD);
1599
1600  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
1601    return EmitFunctionDeclLValue(*this, E, FD);
1602
1603  assert(false && "Unhandled member declaration!");
1604  return LValue();
1605}
1606
1607LValue CodeGenFunction::EmitLValueForBitfield(llvm::Value *BaseValue,
1608                                              const FieldDecl *Field,
1609                                              unsigned CVRQualifiers) {
1610  const CGRecordLayout &RL =
1611    CGM.getTypes().getCGRecordLayout(Field->getParent());
1612  const CGBitFieldInfo &Info = RL.getBitFieldInfo(Field);
1613  return LValue::MakeBitfield(BaseValue, Info,
1614                             Field->getType().getCVRQualifiers()|CVRQualifiers);
1615}
1616
1617/// EmitLValueForAnonRecordField - Given that the field is a member of
1618/// an anonymous struct or union buried inside a record, and given
1619/// that the base value is a pointer to the enclosing record, derive
1620/// an lvalue for the ultimate field.
1621LValue CodeGenFunction::EmitLValueForAnonRecordField(llvm::Value *BaseValue,
1622                                             const IndirectFieldDecl *Field,
1623                                                     unsigned CVRQualifiers) {
1624  IndirectFieldDecl::chain_iterator I = Field->chain_begin(),
1625    IEnd = Field->chain_end();
1626  while (true) {
1627    LValue LV = EmitLValueForField(BaseValue, cast<FieldDecl>(*I), CVRQualifiers);
1628    if (++I == IEnd) return LV;
1629
1630    assert(LV.isSimple());
1631    BaseValue = LV.getAddress();
1632    CVRQualifiers |= LV.getVRQualifiers();
1633  }
1634}
1635
1636LValue CodeGenFunction::EmitLValueForField(llvm::Value *baseAddr,
1637                                           const FieldDecl *field,
1638                                           unsigned cvr) {
1639  if (field->isBitField())
1640    return EmitLValueForBitfield(baseAddr, field, cvr);
1641
1642  const RecordDecl *rec = field->getParent();
1643  QualType type = field->getType();
1644
1645  bool mayAlias = rec->hasAttr<MayAliasAttr>();
1646
1647  llvm::Value *addr;
1648  if (rec->isUnion()) {
1649    // For unions, we just cast to the appropriate type.
1650    assert(!type->isReferenceType() && "union has reference member");
1651
1652    const llvm::Type *llvmType = CGM.getTypes().ConvertTypeForMem(type);
1653    unsigned AS =
1654      cast<llvm::PointerType>(baseAddr->getType())->getAddressSpace();
1655    addr = Builder.CreateBitCast(baseAddr, llvmType->getPointerTo(AS),
1656                                 field->getName());
1657  } else {
1658    // For structs, we GEP to the field that the record layout suggests.
1659    unsigned idx = CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
1660    addr = Builder.CreateStructGEP(baseAddr, idx, field->getName());
1661
1662    // If this is a reference field, load the reference right now.
1663    if (const ReferenceType *refType = type->getAs<ReferenceType>()) {
1664      llvm::LoadInst *load = Builder.CreateLoad(addr, "ref");
1665      if (cvr & Qualifiers::Volatile) load->setVolatile(true);
1666
1667      if (CGM.shouldUseTBAA()) {
1668        llvm::MDNode *tbaa;
1669        if (mayAlias)
1670          tbaa = CGM.getTBAAInfo(getContext().CharTy);
1671        else
1672          tbaa = CGM.getTBAAInfo(type);
1673        CGM.DecorateInstruction(load, tbaa);
1674      }
1675
1676      addr = load;
1677      mayAlias = false;
1678      type = refType->getPointeeType();
1679      cvr = 0; // qualifiers don't recursively apply to referencee
1680    }
1681  }
1682
1683  unsigned alignment = getContext().getDeclAlign(field).getQuantity();
1684  LValue LV = MakeAddrLValue(addr, type, alignment);
1685  LV.getQuals().addCVRQualifiers(cvr);
1686
1687  // __weak attribute on a field is ignored.
1688  if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
1689    LV.getQuals().removeObjCGCAttr();
1690
1691  // Fields of may_alias structs act like 'char' for TBAA purposes.
1692  // FIXME: this should get propagated down through anonymous structs
1693  // and unions.
1694  if (mayAlias && LV.getTBAAInfo())
1695    LV.setTBAAInfo(CGM.getTBAAInfo(getContext().CharTy));
1696
1697  return LV;
1698}
1699
1700LValue
1701CodeGenFunction::EmitLValueForFieldInitialization(llvm::Value *BaseValue,
1702                                                  const FieldDecl *Field,
1703                                                  unsigned CVRQualifiers) {
1704  QualType FieldType = Field->getType();
1705
1706  if (!FieldType->isReferenceType())
1707    return EmitLValueForField(BaseValue, Field, CVRQualifiers);
1708
1709  const CGRecordLayout &RL =
1710    CGM.getTypes().getCGRecordLayout(Field->getParent());
1711  unsigned idx = RL.getLLVMFieldNo(Field);
1712  llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx, "tmp");
1713
1714  assert(!FieldType.getObjCGCAttr() && "fields cannot have GC attrs");
1715
1716  unsigned Alignment = getContext().getDeclAlign(Field).getQuantity();
1717  return MakeAddrLValue(V, FieldType, Alignment);
1718}
1719
1720LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
1721  llvm::Value *DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
1722  const Expr *InitExpr = E->getInitializer();
1723  LValue Result = MakeAddrLValue(DeclPtr, E->getType());
1724
1725  EmitAnyExprToMem(InitExpr, DeclPtr, /*Volatile*/ false, /*Init*/ true);
1726
1727  return Result;
1728}
1729
1730LValue CodeGenFunction::
1731EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) {
1732  if (!expr->isGLValue()) {
1733    // ?: here should be an aggregate.
1734    assert((hasAggregateLLVMType(expr->getType()) &&
1735            !expr->getType()->isAnyComplexType()) &&
1736           "Unexpected conditional operator!");
1737    return EmitAggExprToLValue(expr);
1738  }
1739
1740  const Expr *condExpr = expr->getCond();
1741  bool CondExprBool;
1742  if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
1743    const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr();
1744    if (!CondExprBool) std::swap(live, dead);
1745
1746    if (!ContainsLabel(dead))
1747      return EmitLValue(live);
1748  }
1749
1750  OpaqueValueMapping binding(*this, expr);
1751
1752  llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true");
1753  llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false");
1754  llvm::BasicBlock *contBlock = createBasicBlock("cond.end");
1755
1756  ConditionalEvaluation eval(*this);
1757  EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock);
1758
1759  // Any temporaries created here are conditional.
1760  EmitBlock(lhsBlock);
1761  eval.begin(*this);
1762  LValue lhs = EmitLValue(expr->getTrueExpr());
1763  eval.end(*this);
1764
1765  if (!lhs.isSimple())
1766    return EmitUnsupportedLValue(expr, "conditional operator");
1767
1768  lhsBlock = Builder.GetInsertBlock();
1769  Builder.CreateBr(contBlock);
1770
1771  // Any temporaries created here are conditional.
1772  EmitBlock(rhsBlock);
1773  eval.begin(*this);
1774  LValue rhs = EmitLValue(expr->getFalseExpr());
1775  eval.end(*this);
1776  if (!rhs.isSimple())
1777    return EmitUnsupportedLValue(expr, "conditional operator");
1778  rhsBlock = Builder.GetInsertBlock();
1779
1780  EmitBlock(contBlock);
1781
1782  llvm::PHINode *phi = Builder.CreatePHI(lhs.getAddress()->getType(), 2,
1783                                         "cond-lvalue");
1784  phi->addIncoming(lhs.getAddress(), lhsBlock);
1785  phi->addIncoming(rhs.getAddress(), rhsBlock);
1786  return MakeAddrLValue(phi, expr->getType());
1787}
1788
1789/// EmitCastLValue - Casts are never lvalues unless that cast is a dynamic_cast.
1790/// If the cast is a dynamic_cast, we can have the usual lvalue result,
1791/// otherwise if a cast is needed by the code generator in an lvalue context,
1792/// then it must mean that we need the address of an aggregate in order to
1793/// access one of its fields.  This can happen for all the reasons that casts
1794/// are permitted with aggregate result, including noop aggregate casts, and
1795/// cast from scalar to union.
1796LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
1797  switch (E->getCastKind()) {
1798  case CK_ToVoid:
1799    return EmitUnsupportedLValue(E, "unexpected cast lvalue");
1800
1801  case CK_Dependent:
1802    llvm_unreachable("dependent cast kind in IR gen!");
1803
1804  case CK_GetObjCProperty: {
1805    LValue LV = EmitLValue(E->getSubExpr());
1806    assert(LV.isPropertyRef());
1807    RValue RV = EmitLoadOfPropertyRefLValue(LV);
1808
1809    // Property is an aggregate r-value.
1810    if (RV.isAggregate()) {
1811      return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
1812    }
1813
1814    // Implicit property returns an l-value.
1815    assert(RV.isScalar());
1816    return MakeAddrLValue(RV.getScalarVal(), E->getSubExpr()->getType());
1817  }
1818
1819  case CK_NoOp:
1820  case CK_LValueToRValue:
1821    if (!E->getSubExpr()->Classify(getContext()).isPRValue()
1822        || E->getType()->isRecordType())
1823      return EmitLValue(E->getSubExpr());
1824    // Fall through to synthesize a temporary.
1825
1826  case CK_BitCast:
1827  case CK_ArrayToPointerDecay:
1828  case CK_FunctionToPointerDecay:
1829  case CK_NullToMemberPointer:
1830  case CK_NullToPointer:
1831  case CK_IntegralToPointer:
1832  case CK_PointerToIntegral:
1833  case CK_PointerToBoolean:
1834  case CK_VectorSplat:
1835  case CK_IntegralCast:
1836  case CK_IntegralToBoolean:
1837  case CK_IntegralToFloating:
1838  case CK_FloatingToIntegral:
1839  case CK_FloatingToBoolean:
1840  case CK_FloatingCast:
1841  case CK_FloatingRealToComplex:
1842  case CK_FloatingComplexToReal:
1843  case CK_FloatingComplexToBoolean:
1844  case CK_FloatingComplexCast:
1845  case CK_FloatingComplexToIntegralComplex:
1846  case CK_IntegralRealToComplex:
1847  case CK_IntegralComplexToReal:
1848  case CK_IntegralComplexToBoolean:
1849  case CK_IntegralComplexCast:
1850  case CK_IntegralComplexToFloatingComplex:
1851  case CK_DerivedToBaseMemberPointer:
1852  case CK_BaseToDerivedMemberPointer:
1853  case CK_MemberPointerToBoolean:
1854  case CK_AnyPointerToBlockPointerCast: {
1855    // These casts only produce lvalues when we're binding a reference to a
1856    // temporary realized from a (converted) pure rvalue. Emit the expression
1857    // as a value, copy it into a temporary, and return an lvalue referring to
1858    // that temporary.
1859    llvm::Value *V = CreateMemTemp(E->getType(), "ref.temp");
1860    EmitAnyExprToMem(E, V, false, false);
1861    return MakeAddrLValue(V, E->getType());
1862  }
1863
1864  case CK_Dynamic: {
1865    LValue LV = EmitLValue(E->getSubExpr());
1866    llvm::Value *V = LV.getAddress();
1867    const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(E);
1868    return MakeAddrLValue(EmitDynamicCast(V, DCE), E->getType());
1869  }
1870
1871  case CK_ConstructorConversion:
1872  case CK_UserDefinedConversion:
1873  case CK_AnyPointerToObjCPointerCast:
1874    return EmitLValue(E->getSubExpr());
1875
1876  case CK_UncheckedDerivedToBase:
1877  case CK_DerivedToBase: {
1878    const RecordType *DerivedClassTy =
1879      E->getSubExpr()->getType()->getAs<RecordType>();
1880    CXXRecordDecl *DerivedClassDecl =
1881      cast<CXXRecordDecl>(DerivedClassTy->getDecl());
1882
1883    LValue LV = EmitLValue(E->getSubExpr());
1884    llvm::Value *This = LV.getAddress();
1885
1886    // Perform the derived-to-base conversion
1887    llvm::Value *Base =
1888      GetAddressOfBaseClass(This, DerivedClassDecl,
1889                            E->path_begin(), E->path_end(),
1890                            /*NullCheckValue=*/false);
1891
1892    return MakeAddrLValue(Base, E->getType());
1893  }
1894  case CK_ToUnion:
1895    return EmitAggExprToLValue(E);
1896  case CK_BaseToDerived: {
1897    const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
1898    CXXRecordDecl *DerivedClassDecl =
1899      cast<CXXRecordDecl>(DerivedClassTy->getDecl());
1900
1901    LValue LV = EmitLValue(E->getSubExpr());
1902
1903    // Perform the base-to-derived conversion
1904    llvm::Value *Derived =
1905      GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
1906                               E->path_begin(), E->path_end(),
1907                               /*NullCheckValue=*/false);
1908
1909    return MakeAddrLValue(Derived, E->getType());
1910  }
1911  case CK_LValueBitCast: {
1912    // This must be a reinterpret_cast (or c-style equivalent).
1913    const ExplicitCastExpr *CE = cast<ExplicitCastExpr>(E);
1914
1915    LValue LV = EmitLValue(E->getSubExpr());
1916    llvm::Value *V = Builder.CreateBitCast(LV.getAddress(),
1917                                           ConvertType(CE->getTypeAsWritten()));
1918    return MakeAddrLValue(V, E->getType());
1919  }
1920  case CK_ObjCObjectLValueCast: {
1921    LValue LV = EmitLValue(E->getSubExpr());
1922    QualType ToType = getContext().getLValueReferenceType(E->getType());
1923    llvm::Value *V = Builder.CreateBitCast(LV.getAddress(),
1924                                           ConvertType(ToType));
1925    return MakeAddrLValue(V, E->getType());
1926  }
1927  }
1928
1929  llvm_unreachable("Unhandled lvalue cast kind?");
1930}
1931
1932LValue CodeGenFunction::EmitNullInitializationLValue(
1933                                              const CXXScalarValueInitExpr *E) {
1934  QualType Ty = E->getType();
1935  LValue LV = MakeAddrLValue(CreateMemTemp(Ty), Ty);
1936  EmitNullInitialization(LV.getAddress(), Ty);
1937  return LV;
1938}
1939
1940LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
1941  assert(e->isGLValue() || e->getType()->isRecordType());
1942  return getOpaqueLValueMapping(e);
1943}
1944
1945//===--------------------------------------------------------------------===//
1946//                             Expression Emission
1947//===--------------------------------------------------------------------===//
1948
1949
1950RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
1951                                     ReturnValueSlot ReturnValue) {
1952  if (CGDebugInfo *DI = getDebugInfo()) {
1953    DI->setLocation(E->getLocStart());
1954    DI->UpdateLineDirectiveRegion(Builder);
1955    DI->EmitStopPoint(Builder);
1956  }
1957
1958  // Builtins never have block type.
1959  if (E->getCallee()->getType()->isBlockPointerType())
1960    return EmitBlockCallExpr(E, ReturnValue);
1961
1962  if (const CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(E))
1963    return EmitCXXMemberCallExpr(CE, ReturnValue);
1964
1965  const Decl *TargetDecl = 0;
1966  if (const ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E->getCallee())) {
1967    if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CE->getSubExpr())) {
1968      TargetDecl = DRE->getDecl();
1969      if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(TargetDecl))
1970        if (unsigned builtinID = FD->getBuiltinID())
1971          return EmitBuiltinExpr(FD, builtinID, E);
1972    }
1973  }
1974
1975  if (const CXXOperatorCallExpr *CE = dyn_cast<CXXOperatorCallExpr>(E))
1976    if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(TargetDecl))
1977      return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
1978
1979  if (isa<CXXPseudoDestructorExpr>(E->getCallee()->IgnoreParens())) {
1980    // C++ [expr.pseudo]p1:
1981    //   The result shall only be used as the operand for the function call
1982    //   operator (), and the result of such a call has type void. The only
1983    //   effect is the evaluation of the postfix-expression before the dot or
1984    //   arrow.
1985    EmitScalarExpr(E->getCallee());
1986    return RValue::get(0);
1987  }
1988
1989  llvm::Value *Callee = EmitScalarExpr(E->getCallee());
1990  return EmitCall(E->getCallee()->getType(), Callee, ReturnValue,
1991                  E->arg_begin(), E->arg_end(), TargetDecl);
1992}
1993
1994LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
1995  // Comma expressions just emit their LHS then their RHS as an l-value.
1996  if (E->getOpcode() == BO_Comma) {
1997    EmitIgnoredExpr(E->getLHS());
1998    EnsureInsertPoint();
1999    return EmitLValue(E->getRHS());
2000  }
2001
2002  if (E->getOpcode() == BO_PtrMemD ||
2003      E->getOpcode() == BO_PtrMemI)
2004    return EmitPointerToDataMemberBinaryExpr(E);
2005
2006  assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
2007
2008  if (!hasAggregateLLVMType(E->getType())) {
2009    // __block variables need the RHS evaluated first.
2010    RValue RV = EmitAnyExpr(E->getRHS());
2011    LValue LV = EmitLValue(E->getLHS());
2012    EmitStoreThroughLValue(RV, LV, E->getType());
2013    return LV;
2014  }
2015
2016  if (E->getType()->isAnyComplexType())
2017    return EmitComplexAssignmentLValue(E);
2018
2019  return EmitAggExprToLValue(E);
2020}
2021
2022LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
2023  RValue RV = EmitCallExpr(E);
2024
2025  if (!RV.isScalar())
2026    return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
2027
2028  assert(E->getCallReturnType()->isReferenceType() &&
2029         "Can't have a scalar return unless the return type is a "
2030         "reference type!");
2031
2032  return MakeAddrLValue(RV.getScalarVal(), E->getType());
2033}
2034
2035LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
2036  // FIXME: This shouldn't require another copy.
2037  return EmitAggExprToLValue(E);
2038}
2039
2040LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
2041  assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
2042         && "binding l-value to type which needs a temporary");
2043  AggValueSlot Slot = CreateAggTemp(E->getType(), "tmp");
2044  EmitCXXConstructExpr(E, Slot);
2045  return MakeAddrLValue(Slot.getAddr(), E->getType());
2046}
2047
2048LValue
2049CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
2050  return MakeAddrLValue(EmitCXXTypeidExpr(E), E->getType());
2051}
2052
2053LValue
2054CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
2055  AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
2056  Slot.setLifetimeExternallyManaged();
2057  EmitAggExpr(E->getSubExpr(), Slot);
2058  EmitCXXTemporary(E->getTemporary(), Slot.getAddr());
2059  return MakeAddrLValue(Slot.getAddr(), E->getType());
2060}
2061
2062LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
2063  RValue RV = EmitObjCMessageExpr(E);
2064
2065  if (!RV.isScalar())
2066    return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
2067
2068  assert(E->getMethodDecl()->getResultType()->isReferenceType() &&
2069         "Can't have a scalar return unless the return type is a "
2070         "reference type!");
2071
2072  return MakeAddrLValue(RV.getScalarVal(), E->getType());
2073}
2074
2075LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
2076  llvm::Value *V =
2077    CGM.getObjCRuntime().GetSelector(Builder, E->getSelector(), true);
2078  return MakeAddrLValue(V, E->getType());
2079}
2080
2081llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
2082                                             const ObjCIvarDecl *Ivar) {
2083  return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
2084}
2085
2086LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
2087                                          llvm::Value *BaseValue,
2088                                          const ObjCIvarDecl *Ivar,
2089                                          unsigned CVRQualifiers) {
2090  return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
2091                                                   Ivar, CVRQualifiers);
2092}
2093
2094LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
2095  // FIXME: A lot of the code below could be shared with EmitMemberExpr.
2096  llvm::Value *BaseValue = 0;
2097  const Expr *BaseExpr = E->getBase();
2098  Qualifiers BaseQuals;
2099  QualType ObjectTy;
2100  if (E->isArrow()) {
2101    BaseValue = EmitScalarExpr(BaseExpr);
2102    ObjectTy = BaseExpr->getType()->getPointeeType();
2103    BaseQuals = ObjectTy.getQualifiers();
2104  } else {
2105    LValue BaseLV = EmitLValue(BaseExpr);
2106    // FIXME: this isn't right for bitfields.
2107    BaseValue = BaseLV.getAddress();
2108    ObjectTy = BaseExpr->getType();
2109    BaseQuals = ObjectTy.getQualifiers();
2110  }
2111
2112  LValue LV =
2113    EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
2114                      BaseQuals.getCVRQualifiers());
2115  setObjCGCLValueClass(getContext(), E, LV);
2116  return LV;
2117}
2118
2119LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
2120  // Can only get l-value for message expression returning aggregate type
2121  RValue RV = EmitAnyExprToTemp(E);
2122  return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
2123}
2124
2125RValue CodeGenFunction::EmitCall(QualType CalleeType, llvm::Value *Callee,
2126                                 ReturnValueSlot ReturnValue,
2127                                 CallExpr::const_arg_iterator ArgBeg,
2128                                 CallExpr::const_arg_iterator ArgEnd,
2129                                 const Decl *TargetDecl) {
2130  // Get the actual function type. The callee type will always be a pointer to
2131  // function type or a block pointer type.
2132  assert(CalleeType->isFunctionPointerType() &&
2133         "Call must have function pointer type!");
2134
2135  CalleeType = getContext().getCanonicalType(CalleeType);
2136
2137  const FunctionType *FnType
2138    = cast<FunctionType>(cast<PointerType>(CalleeType)->getPointeeType());
2139
2140  CallArgList Args;
2141  EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), ArgBeg, ArgEnd);
2142
2143  return EmitCall(CGM.getTypes().getFunctionInfo(Args, FnType),
2144                  Callee, ReturnValue, Args, TargetDecl);
2145}
2146
2147LValue CodeGenFunction::
2148EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
2149  llvm::Value *BaseV;
2150  if (E->getOpcode() == BO_PtrMemI)
2151    BaseV = EmitScalarExpr(E->getLHS());
2152  else
2153    BaseV = EmitLValue(E->getLHS()).getAddress();
2154
2155  llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
2156
2157  const MemberPointerType *MPT
2158    = E->getRHS()->getType()->getAs<MemberPointerType>();
2159
2160  llvm::Value *AddV =
2161    CGM.getCXXABI().EmitMemberDataPointerAddress(*this, BaseV, OffsetV, MPT);
2162
2163  return MakeAddrLValue(AddV, MPT->getPointeeType());
2164}
2165