CGExpr.cpp revision ea619177353e0a9f35b7d926a92df0e103515dbe 
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 "CGRecordLayout.h"
18#include "CGObjCRuntime.h"
19#include "clang/AST/ASTContext.h"
20#include "clang/AST/DeclObjC.h"
21#include "llvm/Intrinsics.h"
22#include "clang/Frontend/CodeGenOptions.h"
23#include "llvm/Target/TargetData.h"
24using namespace clang;
25using namespace CodeGen;
26
27//===--------------------------------------------------------------------===//
28//                        Miscellaneous Helper Methods
29//===--------------------------------------------------------------------===//
30
31/// CreateTempAlloca - This creates a alloca and inserts it into the entry
32/// block.
33llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(const llvm::Type *Ty,
34                                                    const llvm::Twine &Name) {
35  if (!Builder.isNamePreserving())
36    return new llvm::AllocaInst(Ty, 0, "", AllocaInsertPt);
37  return new llvm::AllocaInst(Ty, 0, Name, AllocaInsertPt);
38}
39
40void CodeGenFunction::InitTempAlloca(llvm::AllocaInst *Var,
41                                     llvm::Value *Init) {
42  llvm::StoreInst *Store = new llvm::StoreInst(Init, Var);
43  llvm::BasicBlock *Block = AllocaInsertPt->getParent();
44  Block->getInstList().insertAfter(&*AllocaInsertPt, Store);
45}
46
47llvm::AllocaInst *CodeGenFunction::CreateIRTemp(QualType Ty,
48                                                const llvm::Twine &Name) {
49  llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertType(Ty), Name);
50  // FIXME: Should we prefer the preferred type alignment here?
51  CharUnits Align = getContext().getTypeAlignInChars(Ty);
52  Alloc->setAlignment(Align.getQuantity());
53  return Alloc;
54}
55
56llvm::AllocaInst *CodeGenFunction::CreateMemTemp(QualType Ty,
57                                                 const llvm::Twine &Name) {
58  llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertTypeForMem(Ty), Name);
59  // FIXME: Should we prefer the preferred type alignment here?
60  CharUnits Align = getContext().getTypeAlignInChars(Ty);
61  Alloc->setAlignment(Align.getQuantity());
62  return Alloc;
63}
64
65/// EvaluateExprAsBool - Perform the usual unary conversions on the specified
66/// expression and compare the result against zero, returning an Int1Ty value.
67llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
68  QualType BoolTy = getContext().BoolTy;
69  if (E->getType()->isMemberFunctionPointerType()) {
70    LValue LV = EmitAggExprToLValue(E);
71
72    // Get the pointer.
73    llvm::Value *FuncPtr = Builder.CreateStructGEP(LV.getAddress(), 0,
74                                                   "src.ptr");
75    FuncPtr = Builder.CreateLoad(FuncPtr);
76
77    llvm::Value *IsNotNull =
78      Builder.CreateICmpNE(FuncPtr,
79                            llvm::Constant::getNullValue(FuncPtr->getType()),
80                            "tobool");
81
82    return IsNotNull;
83  }
84  if (!E->getType()->isAnyComplexType())
85    return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy);
86
87  return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(),BoolTy);
88}
89
90/// EmitAnyExpr - Emit code to compute the specified expression which can have
91/// any type.  The result is returned as an RValue struct.  If this is an
92/// aggregate expression, the aggloc/agglocvolatile arguments indicate where the
93/// result should be returned.
94RValue CodeGenFunction::EmitAnyExpr(const Expr *E, llvm::Value *AggLoc,
95                                    bool IsAggLocVolatile, bool IgnoreResult,
96                                    bool IsInitializer) {
97  if (!hasAggregateLLVMType(E->getType()))
98    return RValue::get(EmitScalarExpr(E, IgnoreResult));
99  else if (E->getType()->isAnyComplexType())
100    return RValue::getComplex(EmitComplexExpr(E, false, false,
101                                              IgnoreResult, IgnoreResult));
102
103  EmitAggExpr(E, AggLoc, IsAggLocVolatile, IgnoreResult, IsInitializer);
104  return RValue::getAggregate(AggLoc, IsAggLocVolatile);
105}
106
107/// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will
108/// always be accessible even if no aggregate location is provided.
109RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E,
110                                          bool IsAggLocVolatile,
111                                          bool IsInitializer) {
112  llvm::Value *AggLoc = 0;
113
114  if (hasAggregateLLVMType(E->getType()) &&
115      !E->getType()->isAnyComplexType())
116    AggLoc = CreateMemTemp(E->getType(), "agg.tmp");
117  return EmitAnyExpr(E, AggLoc, IsAggLocVolatile, /*IgnoreResult=*/false,
118                     IsInitializer);
119}
120
121/// EmitAnyExprToMem - Evaluate an expression into a given memory
122/// location.
123void CodeGenFunction::EmitAnyExprToMem(const Expr *E,
124                                       llvm::Value *Location,
125                                       bool IsLocationVolatile,
126                                       bool IsInit) {
127  if (E->getType()->isComplexType())
128    EmitComplexExprIntoAddr(E, Location, IsLocationVolatile);
129  else if (hasAggregateLLVMType(E->getType()))
130    EmitAggExpr(E, Location, IsLocationVolatile, /*Ignore*/ false, IsInit);
131  else {
132    RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false));
133    LValue LV = MakeAddrLValue(Location, E->getType());
134    EmitStoreThroughLValue(RV, LV, E->getType());
135  }
136}
137
138/// \brief An adjustment to be made to the temporary created when emitting a
139/// reference binding, which accesses a particular subobject of that temporary.
140struct SubobjectAdjustment {
141  enum { DerivedToBaseAdjustment, FieldAdjustment } Kind;
142
143  union {
144    struct {
145      const CastExpr *BasePath;
146      const CXXRecordDecl *DerivedClass;
147    } DerivedToBase;
148
149    struct {
150      FieldDecl *Field;
151      unsigned CVRQualifiers;
152    } Field;
153  };
154
155  SubobjectAdjustment(const CastExpr *BasePath,
156                      const CXXRecordDecl *DerivedClass)
157    : Kind(DerivedToBaseAdjustment)
158  {
159    DerivedToBase.BasePath = BasePath;
160    DerivedToBase.DerivedClass = DerivedClass;
161  }
162
163  SubobjectAdjustment(FieldDecl *Field, unsigned CVRQualifiers)
164    : Kind(FieldAdjustment)
165  {
166    this->Field.Field = Field;
167    this->Field.CVRQualifiers = CVRQualifiers;
168  }
169};
170
171static llvm::Value *
172CreateReferenceTemporary(CodeGenFunction& CGF, QualType Type,
173                         const NamedDecl *InitializedDecl) {
174  if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(InitializedDecl)) {
175    if (VD->hasGlobalStorage()) {
176      llvm::SmallString<256> Name;
177      CGF.CGM.getMangleContext().mangleReferenceTemporary(VD, Name);
178
179      const llvm::Type *RefTempTy = CGF.ConvertTypeForMem(Type);
180
181      // Create the reference temporary.
182      llvm::GlobalValue *RefTemp =
183        new llvm::GlobalVariable(CGF.CGM.getModule(),
184                                 RefTempTy, /*isConstant=*/false,
185                                 llvm::GlobalValue::InternalLinkage,
186                                 llvm::Constant::getNullValue(RefTempTy),
187                                 Name.str());
188      return RefTemp;
189    }
190  }
191
192  return CGF.CreateMemTemp(Type, "ref.tmp");
193}
194
195static llvm::Value *
196EmitExprForReferenceBinding(CodeGenFunction& CGF, const Expr* E,
197                            llvm::Value *&ReferenceTemporary,
198                            const CXXDestructorDecl *&ReferenceTemporaryDtor,
199                            const NamedDecl *InitializedDecl) {
200  if (const CXXDefaultArgExpr *DAE = dyn_cast<CXXDefaultArgExpr>(E))
201    E = DAE->getExpr();
202
203  if (const CXXExprWithTemporaries *TE = dyn_cast<CXXExprWithTemporaries>(E)) {
204    CodeGenFunction::RunCleanupsScope Scope(CGF);
205
206    return EmitExprForReferenceBinding(CGF, TE->getSubExpr(),
207                                       ReferenceTemporary,
208                                       ReferenceTemporaryDtor,
209                                       InitializedDecl);
210  }
211
212  RValue RV;
213  if (E->isLvalue(CGF.getContext()) == Expr::LV_Valid) {
214    // Emit the expression as an lvalue.
215    LValue LV = CGF.EmitLValue(E);
216
217    if (LV.isSimple())
218      return LV.getAddress();
219
220    // We have to load the lvalue.
221    RV = CGF.EmitLoadOfLValue(LV, E->getType());
222  } else {
223    QualType ResultTy = E->getType();
224
225    llvm::SmallVector<SubobjectAdjustment, 2> Adjustments;
226    while (true) {
227      if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
228        E = PE->getSubExpr();
229        continue;
230      }
231
232      if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
233        if ((CE->getCastKind() == CastExpr::CK_DerivedToBase ||
234             CE->getCastKind() == CastExpr::CK_UncheckedDerivedToBase) &&
235            E->getType()->isRecordType()) {
236          E = CE->getSubExpr();
237          CXXRecordDecl *Derived
238            = cast<CXXRecordDecl>(E->getType()->getAs<RecordType>()->getDecl());
239          Adjustments.push_back(SubobjectAdjustment(CE, Derived));
240          continue;
241        }
242
243        if (CE->getCastKind() == CastExpr::CK_NoOp) {
244          E = CE->getSubExpr();
245          continue;
246        }
247      } else if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
248        if (ME->getBase()->isLvalue(CGF.getContext()) != Expr::LV_Valid &&
249            ME->getBase()->getType()->isRecordType()) {
250          if (FieldDecl *Field = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
251            E = ME->getBase();
252            Adjustments.push_back(SubobjectAdjustment(Field,
253                                              E->getType().getCVRQualifiers()));
254            continue;
255          }
256        }
257      }
258
259      // Nothing changed.
260      break;
261    }
262
263    // Create a reference temporary if necessary.
264    if (CGF.hasAggregateLLVMType(E->getType()) &&
265        !E->getType()->isAnyComplexType())
266      ReferenceTemporary = CreateReferenceTemporary(CGF, E->getType(),
267                                                    InitializedDecl);
268
269    RV = CGF.EmitAnyExpr(E, ReferenceTemporary, /*IsAggLocVolatile=*/false,
270                         /*IgnoreResult=*/false, InitializedDecl);
271
272    if (InitializedDecl) {
273      // Get the destructor for the reference temporary.
274      if (const RecordType *RT = E->getType()->getAs<RecordType>()) {
275        CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
276        if (!ClassDecl->hasTrivialDestructor())
277          ReferenceTemporaryDtor = ClassDecl->getDestructor();
278      }
279    }
280
281    // Check if need to perform derived-to-base casts and/or field accesses, to
282    // get from the temporary object we created (and, potentially, for which we
283    // extended the lifetime) to the subobject we're binding the reference to.
284    if (!Adjustments.empty()) {
285      llvm::Value *Object = RV.getAggregateAddr();
286      for (unsigned I = Adjustments.size(); I != 0; --I) {
287        SubobjectAdjustment &Adjustment = Adjustments[I-1];
288        switch (Adjustment.Kind) {
289        case SubobjectAdjustment::DerivedToBaseAdjustment:
290          Object =
291              CGF.GetAddressOfBaseClass(Object,
292                                        Adjustment.DerivedToBase.DerivedClass,
293                              Adjustment.DerivedToBase.BasePath->path_begin(),
294                              Adjustment.DerivedToBase.BasePath->path_end(),
295                                        /*NullCheckValue=*/false);
296          break;
297
298        case SubobjectAdjustment::FieldAdjustment: {
299          unsigned CVR = Adjustment.Field.CVRQualifiers;
300          LValue LV =
301            CGF.EmitLValueForField(Object, Adjustment.Field.Field, CVR);
302          if (LV.isSimple()) {
303            Object = LV.getAddress();
304            break;
305          }
306
307          // For non-simple lvalues, we actually have to create a copy of
308          // the object we're binding to.
309          QualType T = Adjustment.Field.Field->getType().getNonReferenceType()
310                                                        .getUnqualifiedType();
311          Object = CreateReferenceTemporary(CGF, T, InitializedDecl);
312          LValue TempLV = LValue::MakeAddr(Object,
313                                           Qualifiers::fromCVRMask(CVR));
314          CGF.EmitStoreThroughLValue(CGF.EmitLoadOfLValue(LV, T), TempLV, T);
315          break;
316        }
317
318        }
319      }
320
321      const llvm::Type *ResultPtrTy = CGF.ConvertType(ResultTy)->getPointerTo();
322      return CGF.Builder.CreateBitCast(Object, ResultPtrTy, "temp");
323    }
324  }
325
326  if (RV.isAggregate())
327    return RV.getAggregateAddr();
328
329  // Create a temporary variable that we can bind the reference to.
330  ReferenceTemporary = CreateReferenceTemporary(CGF, E->getType(),
331                                                InitializedDecl);
332
333
334  unsigned Alignment =
335    CGF.getContext().getTypeAlignInChars(E->getType()).getQuantity();
336  if (RV.isScalar())
337    CGF.EmitStoreOfScalar(RV.getScalarVal(), ReferenceTemporary,
338                          /*Volatile=*/false, Alignment, E->getType());
339  else
340    CGF.StoreComplexToAddr(RV.getComplexVal(), ReferenceTemporary,
341                           /*Volatile=*/false);
342  return ReferenceTemporary;
343}
344
345RValue
346CodeGenFunction::EmitReferenceBindingToExpr(const Expr* E,
347                                            const NamedDecl *InitializedDecl) {
348  llvm::Value *ReferenceTemporary = 0;
349  const CXXDestructorDecl *ReferenceTemporaryDtor = 0;
350  llvm::Value *Value = EmitExprForReferenceBinding(*this, E, ReferenceTemporary,
351                                                   ReferenceTemporaryDtor,
352                                                   InitializedDecl);
353
354  if (!ReferenceTemporaryDtor)
355    return RValue::get(Value);
356
357  // Make sure to call the destructor for the reference temporary.
358  if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(InitializedDecl)) {
359    if (VD->hasGlobalStorage()) {
360      llvm::Constant *DtorFn =
361        CGM.GetAddrOfCXXDestructor(ReferenceTemporaryDtor, Dtor_Complete);
362      CGF.EmitCXXGlobalDtorRegistration(DtorFn,
363                                      cast<llvm::Constant>(ReferenceTemporary));
364
365      return RValue::get(Value);
366    }
367  }
368
369  PushDestructorCleanup(ReferenceTemporaryDtor, ReferenceTemporary);
370
371  return RValue::get(Value);
372}
373
374
375/// getAccessedFieldNo - Given an encoded value and a result number, return the
376/// input field number being accessed.
377unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
378                                             const llvm::Constant *Elts) {
379  if (isa<llvm::ConstantAggregateZero>(Elts))
380    return 0;
381
382  return cast<llvm::ConstantInt>(Elts->getOperand(Idx))->getZExtValue();
383}
384
385void CodeGenFunction::EmitCheck(llvm::Value *Address, unsigned Size) {
386  if (!CatchUndefined)
387    return;
388
389  Address = Builder.CreateBitCast(Address, PtrToInt8Ty);
390
391  const llvm::Type *IntPtrT = IntPtrTy;
392  llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, &IntPtrT, 1);
393  const llvm::IntegerType *Int1Ty = llvm::Type::getInt1Ty(VMContext);
394
395  // In time, people may want to control this and use a 1 here.
396  llvm::Value *Arg = llvm::ConstantInt::get(Int1Ty, 0);
397  llvm::Value *C = Builder.CreateCall2(F, Address, Arg);
398  llvm::BasicBlock *Cont = createBasicBlock();
399  llvm::BasicBlock *Check = createBasicBlock();
400  llvm::Value *NegativeOne = llvm::ConstantInt::get(IntPtrTy, -1ULL);
401  Builder.CreateCondBr(Builder.CreateICmpEQ(C, NegativeOne), Cont, Check);
402
403  EmitBlock(Check);
404  Builder.CreateCondBr(Builder.CreateICmpUGE(C,
405                                        llvm::ConstantInt::get(IntPtrTy, Size)),
406                       Cont, getTrapBB());
407  EmitBlock(Cont);
408}
409
410
411CodeGenFunction::ComplexPairTy CodeGenFunction::
412EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
413                         bool isInc, bool isPre) {
414  ComplexPairTy InVal = LoadComplexFromAddr(LV.getAddress(),
415                                            LV.isVolatileQualified());
416
417  llvm::Value *NextVal;
418  if (isa<llvm::IntegerType>(InVal.first->getType())) {
419    uint64_t AmountVal = isInc ? 1 : -1;
420    NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
421
422    // Add the inc/dec to the real part.
423    NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
424  } else {
425    QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
426    llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
427    if (!isInc)
428      FVal.changeSign();
429    NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
430
431    // Add the inc/dec to the real part.
432    NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
433  }
434
435  ComplexPairTy IncVal(NextVal, InVal.second);
436
437  // Store the updated result through the lvalue.
438  StoreComplexToAddr(IncVal, LV.getAddress(), LV.isVolatileQualified());
439
440  // If this is a postinc, return the value read from memory, otherwise use the
441  // updated value.
442  return isPre ? IncVal : InVal;
443}
444
445
446//===----------------------------------------------------------------------===//
447//                         LValue Expression Emission
448//===----------------------------------------------------------------------===//
449
450RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
451  if (Ty->isVoidType())
452    return RValue::get(0);
453
454  if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
455    const llvm::Type *EltTy = ConvertType(CTy->getElementType());
456    llvm::Value *U = llvm::UndefValue::get(EltTy);
457    return RValue::getComplex(std::make_pair(U, U));
458  }
459
460  if (hasAggregateLLVMType(Ty)) {
461    const llvm::Type *LTy = llvm::PointerType::getUnqual(ConvertType(Ty));
462    return RValue::getAggregate(llvm::UndefValue::get(LTy));
463  }
464
465  return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
466}
467
468RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
469                                              const char *Name) {
470  ErrorUnsupported(E, Name);
471  return GetUndefRValue(E->getType());
472}
473
474LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
475                                              const char *Name) {
476  ErrorUnsupported(E, Name);
477  llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
478  return MakeAddrLValue(llvm::UndefValue::get(Ty), E->getType());
479}
480
481LValue CodeGenFunction::EmitCheckedLValue(const Expr *E) {
482  LValue LV = EmitLValue(E);
483  if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple())
484    EmitCheck(LV.getAddress(), getContext().getTypeSize(E->getType()) / 8);
485  return LV;
486}
487
488/// EmitLValue - Emit code to compute a designator that specifies the location
489/// of the expression.
490///
491/// This can return one of two things: a simple address or a bitfield reference.
492/// In either case, the LLVM Value* in the LValue structure is guaranteed to be
493/// an LLVM pointer type.
494///
495/// If this returns a bitfield reference, nothing about the pointee type of the
496/// LLVM value is known: For example, it may not be a pointer to an integer.
497///
498/// If this returns a normal address, and if the lvalue's C type is fixed size,
499/// this method guarantees that the returned pointer type will point to an LLVM
500/// type of the same size of the lvalue's type.  If the lvalue has a variable
501/// length type, this is not possible.
502///
503LValue CodeGenFunction::EmitLValue(const Expr *E) {
504  switch (E->getStmtClass()) {
505  default: return EmitUnsupportedLValue(E, "l-value expression");
506
507  case Expr::ObjCSelectorExprClass:
508  return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
509  case Expr::ObjCIsaExprClass:
510    return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
511  case Expr::BinaryOperatorClass:
512    return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
513  case Expr::CompoundAssignOperatorClass:
514    return EmitCompoundAssignOperatorLValue(cast<CompoundAssignOperator>(E));
515  case Expr::CallExprClass:
516  case Expr::CXXMemberCallExprClass:
517  case Expr::CXXOperatorCallExprClass:
518    return EmitCallExprLValue(cast<CallExpr>(E));
519  case Expr::VAArgExprClass:
520    return EmitVAArgExprLValue(cast<VAArgExpr>(E));
521  case Expr::DeclRefExprClass:
522    return EmitDeclRefLValue(cast<DeclRefExpr>(E));
523  case Expr::ParenExprClass:return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
524  case Expr::PredefinedExprClass:
525    return EmitPredefinedLValue(cast<PredefinedExpr>(E));
526  case Expr::StringLiteralClass:
527    return EmitStringLiteralLValue(cast<StringLiteral>(E));
528  case Expr::ObjCEncodeExprClass:
529    return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
530
531  case Expr::BlockDeclRefExprClass:
532    return EmitBlockDeclRefLValue(cast<BlockDeclRefExpr>(E));
533
534  case Expr::CXXTemporaryObjectExprClass:
535  case Expr::CXXConstructExprClass:
536    return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
537  case Expr::CXXBindTemporaryExprClass:
538    return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
539  case Expr::CXXExprWithTemporariesClass:
540    return EmitCXXExprWithTemporariesLValue(cast<CXXExprWithTemporaries>(E));
541  case Expr::CXXScalarValueInitExprClass:
542    return EmitNullInitializationLValue(cast<CXXScalarValueInitExpr>(E));
543  case Expr::CXXDefaultArgExprClass:
544    return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr());
545  case Expr::CXXTypeidExprClass:
546    return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
547
548  case Expr::ObjCMessageExprClass:
549    return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
550  case Expr::ObjCIvarRefExprClass:
551    return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
552  case Expr::ObjCPropertyRefExprClass:
553    return EmitObjCPropertyRefLValue(cast<ObjCPropertyRefExpr>(E));
554  case Expr::ObjCImplicitSetterGetterRefExprClass:
555    return EmitObjCKVCRefLValue(cast<ObjCImplicitSetterGetterRefExpr>(E));
556  case Expr::ObjCSuperExprClass:
557    return EmitObjCSuperExprLValue(cast<ObjCSuperExpr>(E));
558
559  case Expr::StmtExprClass:
560    return EmitStmtExprLValue(cast<StmtExpr>(E));
561  case Expr::UnaryOperatorClass:
562    return EmitUnaryOpLValue(cast<UnaryOperator>(E));
563  case Expr::ArraySubscriptExprClass:
564    return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
565  case Expr::ExtVectorElementExprClass:
566    return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
567  case Expr::MemberExprClass:
568    return EmitMemberExpr(cast<MemberExpr>(E));
569  case Expr::CompoundLiteralExprClass:
570    return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
571  case Expr::ConditionalOperatorClass:
572    return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
573  case Expr::ChooseExprClass:
574    return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(getContext()));
575  case Expr::ImplicitCastExprClass:
576  case Expr::CStyleCastExprClass:
577  case Expr::CXXFunctionalCastExprClass:
578  case Expr::CXXStaticCastExprClass:
579  case Expr::CXXDynamicCastExprClass:
580  case Expr::CXXReinterpretCastExprClass:
581  case Expr::CXXConstCastExprClass:
582    return EmitCastLValue(cast<CastExpr>(E));
583  }
584}
585
586llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile,
587                                              unsigned Alignment, QualType Ty) {
588  llvm::LoadInst *Load = Builder.CreateLoad(Addr, "tmp");
589  if (Volatile)
590    Load->setVolatile(true);
591  if (Alignment)
592    Load->setAlignment(Alignment);
593
594  // Bool can have different representation in memory than in registers.
595  llvm::Value *V = Load;
596  if (Ty->isBooleanType())
597    if (V->getType() != llvm::Type::getInt1Ty(VMContext))
598      V = Builder.CreateTrunc(V, llvm::Type::getInt1Ty(VMContext), "tobool");
599
600  return V;
601}
602
603void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr,
604                                        bool Volatile, unsigned Alignment,
605                                        QualType Ty) {
606
607  if (Ty->isBooleanType()) {
608    // Bool can have different representation in memory than in registers.
609    const llvm::PointerType *DstPtr = cast<llvm::PointerType>(Addr->getType());
610    Value = Builder.CreateIntCast(Value, DstPtr->getElementType(), false);
611  }
612
613  llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
614  if (Alignment)
615    Store->setAlignment(Alignment);
616}
617
618/// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
619/// method emits the address of the lvalue, then loads the result as an rvalue,
620/// returning the rvalue.
621RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, QualType ExprType) {
622  if (LV.isObjCWeak()) {
623    // load of a __weak object.
624    llvm::Value *AddrWeakObj = LV.getAddress();
625    return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
626                                                             AddrWeakObj));
627  }
628
629  if (LV.isSimple()) {
630    llvm::Value *Ptr = LV.getAddress();
631    const llvm::Type *EltTy =
632      cast<llvm::PointerType>(Ptr->getType())->getElementType();
633
634    // Simple scalar l-value.
635    //
636    // FIXME: We shouldn't have to use isSingleValueType here.
637    if (EltTy->isSingleValueType())
638      return RValue::get(EmitLoadOfScalar(Ptr, LV.isVolatileQualified(),
639                                          LV.getAlignment(), ExprType));
640
641    assert(ExprType->isFunctionType() && "Unknown scalar value");
642    return RValue::get(Ptr);
643  }
644
645  if (LV.isVectorElt()) {
646    llvm::Value *Vec = Builder.CreateLoad(LV.getVectorAddr(),
647                                          LV.isVolatileQualified(), "tmp");
648    return RValue::get(Builder.CreateExtractElement(Vec, LV.getVectorIdx(),
649                                                    "vecext"));
650  }
651
652  // If this is a reference to a subset of the elements of a vector, either
653  // shuffle the input or extract/insert them as appropriate.
654  if (LV.isExtVectorElt())
655    return EmitLoadOfExtVectorElementLValue(LV, ExprType);
656
657  if (LV.isBitField())
658    return EmitLoadOfBitfieldLValue(LV, ExprType);
659
660  if (LV.isPropertyRef())
661    return EmitLoadOfPropertyRefLValue(LV, ExprType);
662
663  assert(LV.isKVCRef() && "Unknown LValue type!");
664  return EmitLoadOfKVCRefLValue(LV, ExprType);
665}
666
667RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
668                                                 QualType ExprType) {
669  const CGBitFieldInfo &Info = LV.getBitFieldInfo();
670
671  // Get the output type.
672  const llvm::Type *ResLTy = ConvertType(ExprType);
673  unsigned ResSizeInBits = CGM.getTargetData().getTypeSizeInBits(ResLTy);
674
675  // Compute the result as an OR of all of the individual component accesses.
676  llvm::Value *Res = 0;
677  for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) {
678    const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i);
679
680    // Get the field pointer.
681    llvm::Value *Ptr = LV.getBitFieldBaseAddr();
682
683    // Only offset by the field index if used, so that incoming values are not
684    // required to be structures.
685    if (AI.FieldIndex)
686      Ptr = Builder.CreateStructGEP(Ptr, AI.FieldIndex, "bf.field");
687
688    // Offset by the byte offset, if used.
689    if (AI.FieldByteOffset) {
690      const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext);
691      Ptr = Builder.CreateBitCast(Ptr, i8PTy);
692      Ptr = Builder.CreateConstGEP1_32(Ptr, AI.FieldByteOffset,"bf.field.offs");
693    }
694
695    // Cast to the access type.
696    const llvm::Type *PTy = llvm::Type::getIntNPtrTy(VMContext, AI.AccessWidth,
697                                                    ExprType.getAddressSpace());
698    Ptr = Builder.CreateBitCast(Ptr, PTy);
699
700    // Perform the load.
701    llvm::LoadInst *Load = Builder.CreateLoad(Ptr, LV.isVolatileQualified());
702    if (AI.AccessAlignment)
703      Load->setAlignment(AI.AccessAlignment);
704
705    // Shift out unused low bits and mask out unused high bits.
706    llvm::Value *Val = Load;
707    if (AI.FieldBitStart)
708      Val = Builder.CreateLShr(Load, AI.FieldBitStart);
709    Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(AI.AccessWidth,
710                                                            AI.TargetBitWidth),
711                            "bf.clear");
712
713    // Extend or truncate to the target size.
714    if (AI.AccessWidth < ResSizeInBits)
715      Val = Builder.CreateZExt(Val, ResLTy);
716    else if (AI.AccessWidth > ResSizeInBits)
717      Val = Builder.CreateTrunc(Val, ResLTy);
718
719    // Shift into place, and OR into the result.
720    if (AI.TargetBitOffset)
721      Val = Builder.CreateShl(Val, AI.TargetBitOffset);
722    Res = Res ? Builder.CreateOr(Res, Val) : Val;
723  }
724
725  // If the bit-field is signed, perform the sign-extension.
726  //
727  // FIXME: This can easily be folded into the load of the high bits, which
728  // could also eliminate the mask of high bits in some situations.
729  if (Info.isSigned()) {
730    unsigned ExtraBits = ResSizeInBits - Info.getSize();
731    if (ExtraBits)
732      Res = Builder.CreateAShr(Builder.CreateShl(Res, ExtraBits),
733                               ExtraBits, "bf.val.sext");
734  }
735
736  return RValue::get(Res);
737}
738
739RValue CodeGenFunction::EmitLoadOfPropertyRefLValue(LValue LV,
740                                                    QualType ExprType) {
741  return EmitObjCPropertyGet(LV.getPropertyRefExpr());
742}
743
744RValue CodeGenFunction::EmitLoadOfKVCRefLValue(LValue LV,
745                                               QualType ExprType) {
746  return EmitObjCPropertyGet(LV.getKVCRefExpr());
747}
748
749// If this is a reference to a subset of the elements of a vector, create an
750// appropriate shufflevector.
751RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV,
752                                                         QualType ExprType) {
753  llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddr(),
754                                        LV.isVolatileQualified(), "tmp");
755
756  const llvm::Constant *Elts = LV.getExtVectorElts();
757
758  // If the result of the expression is a non-vector type, we must be extracting
759  // a single element.  Just codegen as an extractelement.
760  const VectorType *ExprVT = ExprType->getAs<VectorType>();
761  if (!ExprVT) {
762    unsigned InIdx = getAccessedFieldNo(0, Elts);
763    llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx);
764    return RValue::get(Builder.CreateExtractElement(Vec, Elt, "tmp"));
765  }
766
767  // Always use shuffle vector to try to retain the original program structure
768  unsigned NumResultElts = ExprVT->getNumElements();
769
770  llvm::SmallVector<llvm::Constant*, 4> Mask;
771  for (unsigned i = 0; i != NumResultElts; ++i) {
772    unsigned InIdx = getAccessedFieldNo(i, Elts);
773    Mask.push_back(llvm::ConstantInt::get(Int32Ty, InIdx));
774  }
775
776  llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
777  Vec = Builder.CreateShuffleVector(Vec,
778                                    llvm::UndefValue::get(Vec->getType()),
779                                    MaskV, "tmp");
780  return RValue::get(Vec);
781}
782
783
784
785/// EmitStoreThroughLValue - Store the specified rvalue into the specified
786/// lvalue, where both are guaranteed to the have the same type, and that type
787/// is 'Ty'.
788void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
789                                             QualType Ty) {
790  if (!Dst.isSimple()) {
791    if (Dst.isVectorElt()) {
792      // Read/modify/write the vector, inserting the new element.
793      llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddr(),
794                                            Dst.isVolatileQualified(), "tmp");
795      Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
796                                        Dst.getVectorIdx(), "vecins");
797      Builder.CreateStore(Vec, Dst.getVectorAddr(),Dst.isVolatileQualified());
798      return;
799    }
800
801    // If this is an update of extended vector elements, insert them as
802    // appropriate.
803    if (Dst.isExtVectorElt())
804      return EmitStoreThroughExtVectorComponentLValue(Src, Dst, Ty);
805
806    if (Dst.isBitField())
807      return EmitStoreThroughBitfieldLValue(Src, Dst, Ty);
808
809    if (Dst.isPropertyRef())
810      return EmitStoreThroughPropertyRefLValue(Src, Dst, Ty);
811
812    assert(Dst.isKVCRef() && "Unknown LValue type");
813    return EmitStoreThroughKVCRefLValue(Src, Dst, Ty);
814  }
815
816  if (Dst.isObjCWeak() && !Dst.isNonGC()) {
817    // load of a __weak object.
818    llvm::Value *LvalueDst = Dst.getAddress();
819    llvm::Value *src = Src.getScalarVal();
820     CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
821    return;
822  }
823
824  if (Dst.isObjCStrong() && !Dst.isNonGC()) {
825    // load of a __strong object.
826    llvm::Value *LvalueDst = Dst.getAddress();
827    llvm::Value *src = Src.getScalarVal();
828    if (Dst.isObjCIvar()) {
829      assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
830      const llvm::Type *ResultType = ConvertType(getContext().LongTy);
831      llvm::Value *RHS = EmitScalarExpr(Dst.getBaseIvarExp());
832      llvm::Value *dst = RHS;
833      RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
834      llvm::Value *LHS =
835        Builder.CreatePtrToInt(LvalueDst, ResultType, "sub.ptr.lhs.cast");
836      llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
837      CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
838                                              BytesBetween);
839    } else if (Dst.isGlobalObjCRef()) {
840      CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
841                                                Dst.isThreadLocalRef());
842    }
843    else
844      CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
845    return;
846  }
847
848  assert(Src.isScalar() && "Can't emit an agg store with this method");
849  EmitStoreOfScalar(Src.getScalarVal(), Dst.getAddress(),
850                    Dst.isVolatileQualified(), Dst.getAlignment(), Ty);
851}
852
853void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
854                                                     QualType Ty,
855                                                     llvm::Value **Result) {
856  const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
857
858  // Get the output type.
859  const llvm::Type *ResLTy = ConvertTypeForMem(Ty);
860  unsigned ResSizeInBits = CGM.getTargetData().getTypeSizeInBits(ResLTy);
861
862  // Get the source value, truncated to the width of the bit-field.
863  llvm::Value *SrcVal = Src.getScalarVal();
864
865  if (Ty->isBooleanType())
866    SrcVal = Builder.CreateIntCast(SrcVal, ResLTy, /*IsSigned=*/false);
867
868  SrcVal = Builder.CreateAnd(SrcVal, llvm::APInt::getLowBitsSet(ResSizeInBits,
869                                                                Info.getSize()),
870                             "bf.value");
871
872  // Return the new value of the bit-field, if requested.
873  if (Result) {
874    // Cast back to the proper type for result.
875    const llvm::Type *SrcTy = Src.getScalarVal()->getType();
876    llvm::Value *ReloadVal = Builder.CreateIntCast(SrcVal, SrcTy, false,
877                                                   "bf.reload.val");
878
879    // Sign extend if necessary.
880    if (Info.isSigned()) {
881      unsigned ExtraBits = ResSizeInBits - Info.getSize();
882      if (ExtraBits)
883        ReloadVal = Builder.CreateAShr(Builder.CreateShl(ReloadVal, ExtraBits),
884                                       ExtraBits, "bf.reload.sext");
885    }
886
887    *Result = ReloadVal;
888  }
889
890  // Iterate over the components, writing each piece to memory.
891  for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) {
892    const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i);
893
894    // Get the field pointer.
895    llvm::Value *Ptr = Dst.getBitFieldBaseAddr();
896
897    // Only offset by the field index if used, so that incoming values are not
898    // required to be structures.
899    if (AI.FieldIndex)
900      Ptr = Builder.CreateStructGEP(Ptr, AI.FieldIndex, "bf.field");
901
902    // Offset by the byte offset, if used.
903    if (AI.FieldByteOffset) {
904      const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext);
905      Ptr = Builder.CreateBitCast(Ptr, i8PTy);
906      Ptr = Builder.CreateConstGEP1_32(Ptr, AI.FieldByteOffset,"bf.field.offs");
907    }
908
909    // Cast to the access type.
910    const llvm::Type *PTy = llvm::Type::getIntNPtrTy(VMContext, AI.AccessWidth,
911                                                     Ty.getAddressSpace());
912    Ptr = Builder.CreateBitCast(Ptr, PTy);
913
914    // Extract the piece of the bit-field value to write in this access, limited
915    // to the values that are part of this access.
916    llvm::Value *Val = SrcVal;
917    if (AI.TargetBitOffset)
918      Val = Builder.CreateLShr(Val, AI.TargetBitOffset);
919    Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(ResSizeInBits,
920                                                            AI.TargetBitWidth));
921
922    // Extend or truncate to the access size.
923    const llvm::Type *AccessLTy =
924      llvm::Type::getIntNTy(VMContext, AI.AccessWidth);
925    if (ResSizeInBits < AI.AccessWidth)
926      Val = Builder.CreateZExt(Val, AccessLTy);
927    else if (ResSizeInBits > AI.AccessWidth)
928      Val = Builder.CreateTrunc(Val, AccessLTy);
929
930    // Shift into the position in memory.
931    if (AI.FieldBitStart)
932      Val = Builder.CreateShl(Val, AI.FieldBitStart);
933
934    // If necessary, load and OR in bits that are outside of the bit-field.
935    if (AI.TargetBitWidth != AI.AccessWidth) {
936      llvm::LoadInst *Load = Builder.CreateLoad(Ptr, Dst.isVolatileQualified());
937      if (AI.AccessAlignment)
938        Load->setAlignment(AI.AccessAlignment);
939
940      // Compute the mask for zeroing the bits that are part of the bit-field.
941      llvm::APInt InvMask =
942        ~llvm::APInt::getBitsSet(AI.AccessWidth, AI.FieldBitStart,
943                                 AI.FieldBitStart + AI.TargetBitWidth);
944
945      // Apply the mask and OR in to the value to write.
946      Val = Builder.CreateOr(Builder.CreateAnd(Load, InvMask), Val);
947    }
948
949    // Write the value.
950    llvm::StoreInst *Store = Builder.CreateStore(Val, Ptr,
951                                                 Dst.isVolatileQualified());
952    if (AI.AccessAlignment)
953      Store->setAlignment(AI.AccessAlignment);
954  }
955}
956
957void CodeGenFunction::EmitStoreThroughPropertyRefLValue(RValue Src,
958                                                        LValue Dst,
959                                                        QualType Ty) {
960  EmitObjCPropertySet(Dst.getPropertyRefExpr(), Src);
961}
962
963void CodeGenFunction::EmitStoreThroughKVCRefLValue(RValue Src,
964                                                   LValue Dst,
965                                                   QualType Ty) {
966  EmitObjCPropertySet(Dst.getKVCRefExpr(), Src);
967}
968
969void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
970                                                               LValue Dst,
971                                                               QualType Ty) {
972  // This access turns into a read/modify/write of the vector.  Load the input
973  // value now.
974  llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddr(),
975                                        Dst.isVolatileQualified(), "tmp");
976  const llvm::Constant *Elts = Dst.getExtVectorElts();
977
978  llvm::Value *SrcVal = Src.getScalarVal();
979
980  if (const VectorType *VTy = Ty->getAs<VectorType>()) {
981    unsigned NumSrcElts = VTy->getNumElements();
982    unsigned NumDstElts =
983       cast<llvm::VectorType>(Vec->getType())->getNumElements();
984    if (NumDstElts == NumSrcElts) {
985      // Use shuffle vector is the src and destination are the same number of
986      // elements and restore the vector mask since it is on the side it will be
987      // stored.
988      llvm::SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
989      for (unsigned i = 0; i != NumSrcElts; ++i) {
990        unsigned InIdx = getAccessedFieldNo(i, Elts);
991        Mask[InIdx] = llvm::ConstantInt::get(Int32Ty, i);
992      }
993
994      llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
995      Vec = Builder.CreateShuffleVector(SrcVal,
996                                        llvm::UndefValue::get(Vec->getType()),
997                                        MaskV, "tmp");
998    } else if (NumDstElts > NumSrcElts) {
999      // Extended the source vector to the same length and then shuffle it
1000      // into the destination.
1001      // FIXME: since we're shuffling with undef, can we just use the indices
1002      //        into that?  This could be simpler.
1003      llvm::SmallVector<llvm::Constant*, 4> ExtMask;
1004      unsigned i;
1005      for (i = 0; i != NumSrcElts; ++i)
1006        ExtMask.push_back(llvm::ConstantInt::get(Int32Ty, i));
1007      for (; i != NumDstElts; ++i)
1008        ExtMask.push_back(llvm::UndefValue::get(Int32Ty));
1009      llvm::Value *ExtMaskV = llvm::ConstantVector::get(&ExtMask[0],
1010                                                        ExtMask.size());
1011      llvm::Value *ExtSrcVal =
1012        Builder.CreateShuffleVector(SrcVal,
1013                                    llvm::UndefValue::get(SrcVal->getType()),
1014                                    ExtMaskV, "tmp");
1015      // build identity
1016      llvm::SmallVector<llvm::Constant*, 4> Mask;
1017      for (unsigned i = 0; i != NumDstElts; ++i)
1018        Mask.push_back(llvm::ConstantInt::get(Int32Ty, i));
1019
1020      // modify when what gets shuffled in
1021      for (unsigned i = 0; i != NumSrcElts; ++i) {
1022        unsigned Idx = getAccessedFieldNo(i, Elts);
1023        Mask[Idx] = llvm::ConstantInt::get(Int32Ty, i+NumDstElts);
1024      }
1025      llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
1026      Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV, "tmp");
1027    } else {
1028      // We should never shorten the vector
1029      assert(0 && "unexpected shorten vector length");
1030    }
1031  } else {
1032    // If the Src is a scalar (not a vector) it must be updating one element.
1033    unsigned InIdx = getAccessedFieldNo(0, Elts);
1034    llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx);
1035    Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt, "tmp");
1036  }
1037
1038  Builder.CreateStore(Vec, Dst.getExtVectorAddr(), Dst.isVolatileQualified());
1039}
1040
1041// setObjCGCLValueClass - sets class of he lvalue for the purpose of
1042// generating write-barries API. It is currently a global, ivar,
1043// or neither.
1044static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
1045                                 LValue &LV) {
1046  if (Ctx.getLangOptions().getGCMode() == LangOptions::NonGC)
1047    return;
1048
1049  if (isa<ObjCIvarRefExpr>(E)) {
1050    LV.SetObjCIvar(LV, true);
1051    ObjCIvarRefExpr *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr*>(E));
1052    LV.setBaseIvarExp(Exp->getBase());
1053    LV.SetObjCArray(LV, E->getType()->isArrayType());
1054    return;
1055  }
1056
1057  if (const DeclRefExpr *Exp = dyn_cast<DeclRefExpr>(E)) {
1058    if (const VarDecl *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
1059      if ((VD->isBlockVarDecl() && !VD->hasLocalStorage()) ||
1060          VD->isFileVarDecl()) {
1061        LV.SetGlobalObjCRef(LV, true);
1062        LV.SetThreadLocalRef(LV, VD->isThreadSpecified());
1063      }
1064    }
1065    LV.SetObjCArray(LV, E->getType()->isArrayType());
1066    return;
1067  }
1068
1069  if (const UnaryOperator *Exp = dyn_cast<UnaryOperator>(E)) {
1070    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1071    return;
1072  }
1073
1074  if (const ParenExpr *Exp = dyn_cast<ParenExpr>(E)) {
1075    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1076    if (LV.isObjCIvar()) {
1077      // If cast is to a structure pointer, follow gcc's behavior and make it
1078      // a non-ivar write-barrier.
1079      QualType ExpTy = E->getType();
1080      if (ExpTy->isPointerType())
1081        ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
1082      if (ExpTy->isRecordType())
1083        LV.SetObjCIvar(LV, false);
1084    }
1085    return;
1086  }
1087  if (const ImplicitCastExpr *Exp = dyn_cast<ImplicitCastExpr>(E)) {
1088    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1089    return;
1090  }
1091
1092  if (const CStyleCastExpr *Exp = dyn_cast<CStyleCastExpr>(E)) {
1093    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1094    return;
1095  }
1096
1097  if (const ArraySubscriptExpr *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
1098    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
1099    if (LV.isObjCIvar() && !LV.isObjCArray())
1100      // Using array syntax to assigning to what an ivar points to is not
1101      // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
1102      LV.SetObjCIvar(LV, false);
1103    else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
1104      // Using array syntax to assigning to what global points to is not
1105      // same as assigning to the global itself. {id *G;} G[i] = 0;
1106      LV.SetGlobalObjCRef(LV, false);
1107    return;
1108  }
1109
1110  if (const MemberExpr *Exp = dyn_cast<MemberExpr>(E)) {
1111    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
1112    // We don't know if member is an 'ivar', but this flag is looked at
1113    // only in the context of LV.isObjCIvar().
1114    LV.SetObjCArray(LV, E->getType()->isArrayType());
1115    return;
1116  }
1117}
1118
1119static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
1120                                      const Expr *E, const VarDecl *VD) {
1121  assert((VD->hasExternalStorage() || VD->isFileVarDecl()) &&
1122         "Var decl must have external storage or be a file var decl!");
1123
1124  llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
1125  if (VD->getType()->isReferenceType())
1126    V = CGF.Builder.CreateLoad(V, "tmp");
1127  LValue LV = CGF.MakeAddrLValue(V, E->getType());
1128  setObjCGCLValueClass(CGF.getContext(), E, LV);
1129  return LV;
1130}
1131
1132static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
1133                                      const Expr *E, const FunctionDecl *FD) {
1134  llvm::Value* V = CGF.CGM.GetAddrOfFunction(FD);
1135  if (!FD->hasPrototype()) {
1136    if (const FunctionProtoType *Proto =
1137            FD->getType()->getAs<FunctionProtoType>()) {
1138      // Ugly case: for a K&R-style definition, the type of the definition
1139      // isn't the same as the type of a use.  Correct for this with a
1140      // bitcast.
1141      QualType NoProtoType =
1142          CGF.getContext().getFunctionNoProtoType(Proto->getResultType());
1143      NoProtoType = CGF.getContext().getPointerType(NoProtoType);
1144      V = CGF.Builder.CreateBitCast(V, CGF.ConvertType(NoProtoType), "tmp");
1145    }
1146  }
1147  return CGF.MakeAddrLValue(V, E->getType());
1148}
1149
1150LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
1151  const NamedDecl *ND = E->getDecl();
1152
1153  if (ND->hasAttr<WeakRefAttr>()) {
1154    const ValueDecl* VD = cast<ValueDecl>(ND);
1155    llvm::Constant *Aliasee = CGM.GetWeakRefReference(VD);
1156
1157    return MakeAddrLValue(Aliasee, E->getType());
1158  }
1159
1160  if (const VarDecl *VD = dyn_cast<VarDecl>(ND)) {
1161
1162    // Check if this is a global variable.
1163    if (VD->hasExternalStorage() || VD->isFileVarDecl())
1164      return EmitGlobalVarDeclLValue(*this, E, VD);
1165
1166    bool NonGCable = VD->hasLocalStorage() && !VD->hasAttr<BlocksAttr>();
1167
1168    llvm::Value *V = LocalDeclMap[VD];
1169    if (!V && getContext().getLangOptions().CPlusPlus &&
1170        VD->isStaticLocal())
1171      V = CGM.getStaticLocalDeclAddress(VD);
1172    assert(V && "DeclRefExpr not entered in LocalDeclMap?");
1173
1174    Qualifiers Quals = MakeQualifiers(E->getType());
1175    // local variables do not get their gc attribute set.
1176    // local static?
1177    if (NonGCable) Quals.removeObjCGCAttr();
1178
1179    if (VD->hasAttr<BlocksAttr>()) {
1180      V = Builder.CreateStructGEP(V, 1, "forwarding");
1181      V = Builder.CreateLoad(V);
1182      V = Builder.CreateStructGEP(V, getByRefValueLLVMField(VD),
1183                                  VD->getNameAsString());
1184    }
1185    if (VD->getType()->isReferenceType())
1186      V = Builder.CreateLoad(V, "tmp");
1187    LValue LV = LValue::MakeAddr(V, Quals);
1188    if (NonGCable) {
1189      LV.setNonGC(true);
1190    }
1191    setObjCGCLValueClass(getContext(), E, LV);
1192    return LV;
1193  }
1194
1195  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
1196    return EmitFunctionDeclLValue(*this, E, FD);
1197
1198  // FIXME: the qualifier check does not seem sufficient here
1199  if (E->getQualifier()) {
1200    const FieldDecl *FD = cast<FieldDecl>(ND);
1201    llvm::Value *V = CGM.EmitPointerToDataMember(FD);
1202    return MakeAddrLValue(V, FD->getType());
1203  }
1204
1205  assert(false && "Unhandled DeclRefExpr");
1206
1207  // an invalid LValue, but the assert will
1208  // ensure that this point is never reached.
1209  return LValue();
1210}
1211
1212LValue CodeGenFunction::EmitBlockDeclRefLValue(const BlockDeclRefExpr *E) {
1213  return MakeAddrLValue(GetAddrOfBlockDecl(E), E->getType());
1214}
1215
1216LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
1217  // __extension__ doesn't affect lvalue-ness.
1218  if (E->getOpcode() == UnaryOperator::Extension)
1219    return EmitLValue(E->getSubExpr());
1220
1221  QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
1222  switch (E->getOpcode()) {
1223  default: assert(0 && "Unknown unary operator lvalue!");
1224  case UnaryOperator::Deref: {
1225    QualType T = E->getSubExpr()->getType()->getPointeeType();
1226    assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
1227
1228    Qualifiers Quals = MakeQualifiers(T);
1229    Quals.setAddressSpace(ExprTy.getAddressSpace());
1230
1231    LValue LV = LValue::MakeAddr(EmitScalarExpr(E->getSubExpr()), Quals);
1232    // We should not generate __weak write barrier on indirect reference
1233    // of a pointer to object; as in void foo (__weak id *param); *param = 0;
1234    // But, we continue to generate __strong write barrier on indirect write
1235    // into a pointer to object.
1236    if (getContext().getLangOptions().ObjC1 &&
1237        getContext().getLangOptions().getGCMode() != LangOptions::NonGC &&
1238        LV.isObjCWeak())
1239      LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
1240    return LV;
1241  }
1242  case UnaryOperator::Real:
1243  case UnaryOperator::Imag: {
1244    LValue LV = EmitLValue(E->getSubExpr());
1245    unsigned Idx = E->getOpcode() == UnaryOperator::Imag;
1246    return MakeAddrLValue(Builder.CreateStructGEP(LV.getAddress(),
1247                                                    Idx, "idx"),
1248                          ExprTy);
1249  }
1250  case UnaryOperator::PreInc:
1251  case UnaryOperator::PreDec: {
1252    LValue LV = EmitLValue(E->getSubExpr());
1253    bool isInc = E->getOpcode() == UnaryOperator::PreInc;
1254
1255    if (E->getType()->isAnyComplexType())
1256      EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
1257    else
1258      EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
1259    return LV;
1260  }
1261  }
1262}
1263
1264LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
1265  return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
1266                        E->getType());
1267}
1268
1269LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
1270  return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
1271                        E->getType());
1272}
1273
1274
1275LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
1276  switch (E->getIdentType()) {
1277  default:
1278    return EmitUnsupportedLValue(E, "predefined expression");
1279
1280  case PredefinedExpr::Func:
1281  case PredefinedExpr::Function:
1282  case PredefinedExpr::PrettyFunction: {
1283    unsigned Type = E->getIdentType();
1284    std::string GlobalVarName;
1285
1286    switch (Type) {
1287    default: assert(0 && "Invalid type");
1288    case PredefinedExpr::Func:
1289      GlobalVarName = "__func__.";
1290      break;
1291    case PredefinedExpr::Function:
1292      GlobalVarName = "__FUNCTION__.";
1293      break;
1294    case PredefinedExpr::PrettyFunction:
1295      GlobalVarName = "__PRETTY_FUNCTION__.";
1296      break;
1297    }
1298
1299    llvm::StringRef FnName = CurFn->getName();
1300    if (FnName.startswith("\01"))
1301      FnName = FnName.substr(1);
1302    GlobalVarName += FnName;
1303
1304    const Decl *CurDecl = CurCodeDecl;
1305    if (CurDecl == 0)
1306      CurDecl = getContext().getTranslationUnitDecl();
1307
1308    std::string FunctionName =
1309      PredefinedExpr::ComputeName((PredefinedExpr::IdentType)Type, CurDecl);
1310
1311    llvm::Constant *C =
1312      CGM.GetAddrOfConstantCString(FunctionName, GlobalVarName.c_str());
1313    return MakeAddrLValue(C, E->getType());
1314  }
1315  }
1316}
1317
1318llvm::BasicBlock *CodeGenFunction::getTrapBB() {
1319  const CodeGenOptions &GCO = CGM.getCodeGenOpts();
1320
1321  // If we are not optimzing, don't collapse all calls to trap in the function
1322  // to the same call, that way, in the debugger they can see which operation
1323  // did in fact fail.  If we are optimizing, we collapse all calls to trap down
1324  // to just one per function to save on codesize.
1325  if (GCO.OptimizationLevel && TrapBB)
1326    return TrapBB;
1327
1328  llvm::BasicBlock *Cont = 0;
1329  if (HaveInsertPoint()) {
1330    Cont = createBasicBlock("cont");
1331    EmitBranch(Cont);
1332  }
1333  TrapBB = createBasicBlock("trap");
1334  EmitBlock(TrapBB);
1335
1336  llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::trap, 0, 0);
1337  llvm::CallInst *TrapCall = Builder.CreateCall(F);
1338  TrapCall->setDoesNotReturn();
1339  TrapCall->setDoesNotThrow();
1340  Builder.CreateUnreachable();
1341
1342  if (Cont)
1343    EmitBlock(Cont);
1344  return TrapBB;
1345}
1346
1347/// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
1348/// array to pointer, return the array subexpression.
1349static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
1350  // If this isn't just an array->pointer decay, bail out.
1351  const CastExpr *CE = dyn_cast<CastExpr>(E);
1352  if (CE == 0 || CE->getCastKind() != CastExpr::CK_ArrayToPointerDecay)
1353    return 0;
1354
1355  // If this is a decay from variable width array, bail out.
1356  const Expr *SubExpr = CE->getSubExpr();
1357  if (SubExpr->getType()->isVariableArrayType())
1358    return 0;
1359
1360  return SubExpr;
1361}
1362
1363LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E) {
1364  // The index must always be an integer, which is not an aggregate.  Emit it.
1365  llvm::Value *Idx = EmitScalarExpr(E->getIdx());
1366  QualType IdxTy  = E->getIdx()->getType();
1367  bool IdxSigned = IdxTy->isSignedIntegerType();
1368
1369  // If the base is a vector type, then we are forming a vector element lvalue
1370  // with this subscript.
1371  if (E->getBase()->getType()->isVectorType()) {
1372    // Emit the vector as an lvalue to get its address.
1373    LValue LHS = EmitLValue(E->getBase());
1374    assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
1375    Idx = Builder.CreateIntCast(Idx, CGF.Int32Ty, IdxSigned, "vidx");
1376    return LValue::MakeVectorElt(LHS.getAddress(), Idx,
1377                                 E->getBase()->getType().getCVRQualifiers());
1378  }
1379
1380  // Extend or truncate the index type to 32 or 64-bits.
1381  if (!Idx->getType()->isIntegerTy(LLVMPointerWidth))
1382    Idx = Builder.CreateIntCast(Idx, IntPtrTy,
1383                                IdxSigned, "idxprom");
1384
1385  // FIXME: As llvm implements the object size checking, this can come out.
1386  if (CatchUndefined) {
1387    if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E->getBase())){
1388      if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr())) {
1389        if (ICE->getCastKind() == CastExpr::CK_ArrayToPointerDecay) {
1390          if (const ConstantArrayType *CAT
1391              = getContext().getAsConstantArrayType(DRE->getType())) {
1392            llvm::APInt Size = CAT->getSize();
1393            llvm::BasicBlock *Cont = createBasicBlock("cont");
1394            Builder.CreateCondBr(Builder.CreateICmpULE(Idx,
1395                                  llvm::ConstantInt::get(Idx->getType(), Size)),
1396                                 Cont, getTrapBB());
1397            EmitBlock(Cont);
1398          }
1399        }
1400      }
1401    }
1402  }
1403
1404  // We know that the pointer points to a type of the correct size, unless the
1405  // size is a VLA or Objective-C interface.
1406  llvm::Value *Address = 0;
1407  if (const VariableArrayType *VAT =
1408        getContext().getAsVariableArrayType(E->getType())) {
1409    llvm::Value *VLASize = GetVLASize(VAT);
1410
1411    Idx = Builder.CreateMul(Idx, VLASize);
1412
1413    QualType BaseType = getContext().getBaseElementType(VAT);
1414
1415    CharUnits BaseTypeSize = getContext().getTypeSizeInChars(BaseType);
1416    Idx = Builder.CreateUDiv(Idx,
1417                             llvm::ConstantInt::get(Idx->getType(),
1418                                 BaseTypeSize.getQuantity()));
1419
1420    // The base must be a pointer, which is not an aggregate.  Emit it.
1421    llvm::Value *Base = EmitScalarExpr(E->getBase());
1422
1423    Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
1424  } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
1425    // Indexing over an interface, as in "NSString *P; P[4];"
1426    llvm::Value *InterfaceSize =
1427      llvm::ConstantInt::get(Idx->getType(),
1428          getContext().getTypeSizeInChars(OIT).getQuantity());
1429
1430    Idx = Builder.CreateMul(Idx, InterfaceSize);
1431
1432    const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext);
1433
1434    // The base must be a pointer, which is not an aggregate.  Emit it.
1435    llvm::Value *Base = EmitScalarExpr(E->getBase());
1436    Address = Builder.CreateGEP(Builder.CreateBitCast(Base, i8PTy),
1437                                Idx, "arrayidx");
1438    Address = Builder.CreateBitCast(Address, Base->getType());
1439  } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
1440    // If this is A[i] where A is an array, the frontend will have decayed the
1441    // base to be a ArrayToPointerDecay implicit cast.  While correct, it is
1442    // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
1443    // "gep x, i" here.  Emit one "gep A, 0, i".
1444    assert(Array->getType()->isArrayType() &&
1445           "Array to pointer decay must have array source type!");
1446    llvm::Value *ArrayPtr = EmitLValue(Array).getAddress();
1447    llvm::Value *Zero = llvm::ConstantInt::get(Int32Ty, 0);
1448    llvm::Value *Args[] = { Zero, Idx };
1449
1450    Address = Builder.CreateInBoundsGEP(ArrayPtr, Args, Args+2, "arrayidx");
1451  } else {
1452    // The base must be a pointer, which is not an aggregate.  Emit it.
1453    llvm::Value *Base = EmitScalarExpr(E->getBase());
1454    Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
1455  }
1456
1457  QualType T = E->getBase()->getType()->getPointeeType();
1458  assert(!T.isNull() &&
1459         "CodeGenFunction::EmitArraySubscriptExpr(): Illegal base type");
1460
1461  Qualifiers Quals = MakeQualifiers(T);
1462  Quals.setAddressSpace(E->getBase()->getType().getAddressSpace());
1463
1464  LValue LV = LValue::MakeAddr(Address, Quals);
1465  if (getContext().getLangOptions().ObjC1 &&
1466      getContext().getLangOptions().getGCMode() != LangOptions::NonGC) {
1467    LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
1468    setObjCGCLValueClass(getContext(), E, LV);
1469  }
1470  return LV;
1471}
1472
1473static
1474llvm::Constant *GenerateConstantVector(llvm::LLVMContext &VMContext,
1475                                       llvm::SmallVector<unsigned, 4> &Elts) {
1476  llvm::SmallVector<llvm::Constant*, 4> CElts;
1477
1478  const llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext);
1479  for (unsigned i = 0, e = Elts.size(); i != e; ++i)
1480    CElts.push_back(llvm::ConstantInt::get(Int32Ty, Elts[i]));
1481
1482  return llvm::ConstantVector::get(&CElts[0], CElts.size());
1483}
1484
1485LValue CodeGenFunction::
1486EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
1487  // Emit the base vector as an l-value.
1488  LValue Base;
1489
1490  // ExtVectorElementExpr's base can either be a vector or pointer to vector.
1491  if (E->isArrow()) {
1492    // If it is a pointer to a vector, emit the address and form an lvalue with
1493    // it.
1494    llvm::Value *Ptr = EmitScalarExpr(E->getBase());
1495    const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
1496    Qualifiers Quals = MakeQualifiers(PT->getPointeeType());
1497    Quals.removeObjCGCAttr();
1498    Base = LValue::MakeAddr(Ptr, Quals);
1499  } else if (E->getBase()->isLvalue(getContext()) == Expr::LV_Valid) {
1500    // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
1501    // emit the base as an lvalue.
1502    assert(E->getBase()->getType()->isVectorType());
1503    Base = EmitLValue(E->getBase());
1504  } else {
1505    // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
1506    assert(E->getBase()->getType()->getAs<VectorType>() &&
1507           "Result must be a vector");
1508    llvm::Value *Vec = EmitScalarExpr(E->getBase());
1509
1510    // Store the vector to memory (because LValue wants an address).
1511    llvm::Value *VecMem = CreateMemTemp(E->getBase()->getType());
1512    Builder.CreateStore(Vec, VecMem);
1513    Base = LValue::MakeAddr(VecMem, Qualifiers());
1514  }
1515
1516  // Encode the element access list into a vector of unsigned indices.
1517  llvm::SmallVector<unsigned, 4> Indices;
1518  E->getEncodedElementAccess(Indices);
1519
1520  if (Base.isSimple()) {
1521    llvm::Constant *CV = GenerateConstantVector(VMContext, Indices);
1522    return LValue::MakeExtVectorElt(Base.getAddress(), CV,
1523                                    Base.getVRQualifiers());
1524  }
1525  assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
1526
1527  llvm::Constant *BaseElts = Base.getExtVectorElts();
1528  llvm::SmallVector<llvm::Constant *, 4> CElts;
1529
1530  for (unsigned i = 0, e = Indices.size(); i != e; ++i) {
1531    if (isa<llvm::ConstantAggregateZero>(BaseElts))
1532      CElts.push_back(llvm::ConstantInt::get(Int32Ty, 0));
1533    else
1534      CElts.push_back(cast<llvm::Constant>(BaseElts->getOperand(Indices[i])));
1535  }
1536  llvm::Constant *CV = llvm::ConstantVector::get(&CElts[0], CElts.size());
1537  return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV,
1538                                  Base.getVRQualifiers());
1539}
1540
1541LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
1542  bool isNonGC = false;
1543  Expr *BaseExpr = E->getBase();
1544  llvm::Value *BaseValue = NULL;
1545  Qualifiers BaseQuals;
1546
1547  // If this is s.x, emit s as an lvalue.  If it is s->x, emit s as a scalar.
1548  if (E->isArrow()) {
1549    BaseValue = EmitScalarExpr(BaseExpr);
1550    const PointerType *PTy =
1551      BaseExpr->getType()->getAs<PointerType>();
1552    BaseQuals = PTy->getPointeeType().getQualifiers();
1553  } else if (isa<ObjCPropertyRefExpr>(BaseExpr->IgnoreParens()) ||
1554             isa<ObjCImplicitSetterGetterRefExpr>(
1555               BaseExpr->IgnoreParens())) {
1556    RValue RV = EmitObjCPropertyGet(BaseExpr);
1557    BaseValue = RV.getAggregateAddr();
1558    BaseQuals = BaseExpr->getType().getQualifiers();
1559  } else {
1560    LValue BaseLV = EmitLValue(BaseExpr);
1561    if (BaseLV.isNonGC())
1562      isNonGC = true;
1563    // FIXME: this isn't right for bitfields.
1564    BaseValue = BaseLV.getAddress();
1565    QualType BaseTy = BaseExpr->getType();
1566    BaseQuals = BaseTy.getQualifiers();
1567  }
1568
1569  NamedDecl *ND = E->getMemberDecl();
1570  if (FieldDecl *Field = dyn_cast<FieldDecl>(ND)) {
1571    LValue LV = EmitLValueForField(BaseValue, Field,
1572                                   BaseQuals.getCVRQualifiers());
1573    LV.setNonGC(isNonGC);
1574    setObjCGCLValueClass(getContext(), E, LV);
1575    return LV;
1576  }
1577
1578  if (VarDecl *VD = dyn_cast<VarDecl>(ND))
1579    return EmitGlobalVarDeclLValue(*this, E, VD);
1580
1581  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
1582    return EmitFunctionDeclLValue(*this, E, FD);
1583
1584  assert(false && "Unhandled member declaration!");
1585  return LValue();
1586}
1587
1588LValue CodeGenFunction::EmitLValueForBitfield(llvm::Value* BaseValue,
1589                                              const FieldDecl* Field,
1590                                              unsigned CVRQualifiers) {
1591  const CGRecordLayout &RL =
1592    CGM.getTypes().getCGRecordLayout(Field->getParent());
1593  const CGBitFieldInfo &Info = RL.getBitFieldInfo(Field);
1594  return LValue::MakeBitfield(BaseValue, Info,
1595                             Field->getType().getCVRQualifiers()|CVRQualifiers);
1596}
1597
1598/// EmitLValueForAnonRecordField - Given that the field is a member of
1599/// an anonymous struct or union buried inside a record, and given
1600/// that the base value is a pointer to the enclosing record, derive
1601/// an lvalue for the ultimate field.
1602LValue CodeGenFunction::EmitLValueForAnonRecordField(llvm::Value *BaseValue,
1603                                                     const FieldDecl *Field,
1604                                                     unsigned CVRQualifiers) {
1605  llvm::SmallVector<const FieldDecl *, 8> Path;
1606  Path.push_back(Field);
1607
1608  while (Field->getParent()->isAnonymousStructOrUnion()) {
1609    const ValueDecl *VD = Field->getParent()->getAnonymousStructOrUnionObject();
1610    if (!isa<FieldDecl>(VD)) break;
1611    Field = cast<FieldDecl>(VD);
1612    Path.push_back(Field);
1613  }
1614
1615  llvm::SmallVectorImpl<const FieldDecl*>::reverse_iterator
1616    I = Path.rbegin(), E = Path.rend();
1617  while (true) {
1618    LValue LV = EmitLValueForField(BaseValue, *I, CVRQualifiers);
1619    if (++I == E) return LV;
1620
1621    assert(LV.isSimple());
1622    BaseValue = LV.getAddress();
1623    CVRQualifiers |= LV.getVRQualifiers();
1624  }
1625}
1626
1627LValue CodeGenFunction::EmitLValueForField(llvm::Value* BaseValue,
1628                                           const FieldDecl* Field,
1629                                           unsigned CVRQualifiers) {
1630  if (Field->isBitField())
1631    return EmitLValueForBitfield(BaseValue, Field, CVRQualifiers);
1632
1633  const CGRecordLayout &RL =
1634    CGM.getTypes().getCGRecordLayout(Field->getParent());
1635  unsigned idx = RL.getLLVMFieldNo(Field);
1636  llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx, "tmp");
1637
1638  // Match union field type.
1639  if (Field->getParent()->isUnion()) {
1640    const llvm::Type *FieldTy =
1641      CGM.getTypes().ConvertTypeForMem(Field->getType());
1642    const llvm::PointerType * BaseTy =
1643      cast<llvm::PointerType>(BaseValue->getType());
1644    unsigned AS = BaseTy->getAddressSpace();
1645    V = Builder.CreateBitCast(V,
1646                              llvm::PointerType::get(FieldTy, AS),
1647                              "tmp");
1648  }
1649  if (Field->getType()->isReferenceType())
1650    V = Builder.CreateLoad(V, "tmp");
1651
1652  Qualifiers Quals = MakeQualifiers(Field->getType());
1653  Quals.addCVRQualifiers(CVRQualifiers);
1654  // __weak attribute on a field is ignored.
1655  if (Quals.getObjCGCAttr() == Qualifiers::Weak)
1656    Quals.removeObjCGCAttr();
1657
1658  return LValue::MakeAddr(V, Quals);
1659}
1660
1661LValue
1662CodeGenFunction::EmitLValueForFieldInitialization(llvm::Value* BaseValue,
1663                                                  const FieldDecl* Field,
1664                                                  unsigned CVRQualifiers) {
1665  QualType FieldType = Field->getType();
1666
1667  if (!FieldType->isReferenceType())
1668    return EmitLValueForField(BaseValue, Field, CVRQualifiers);
1669
1670  const CGRecordLayout &RL =
1671    CGM.getTypes().getCGRecordLayout(Field->getParent());
1672  unsigned idx = RL.getLLVMFieldNo(Field);
1673  llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx, "tmp");
1674
1675  assert(!FieldType.getObjCGCAttr() && "fields cannot have GC attrs");
1676
1677  return MakeAddrLValue(V, FieldType);
1678}
1679
1680LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr* E){
1681  llvm::Value *DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
1682  const Expr* InitExpr = E->getInitializer();
1683  LValue Result = MakeAddrLValue(DeclPtr, E->getType());
1684
1685  EmitAnyExprToMem(InitExpr, DeclPtr, /*Volatile*/ false);
1686
1687  return Result;
1688}
1689
1690LValue
1691CodeGenFunction::EmitConditionalOperatorLValue(const ConditionalOperator* E) {
1692  if (E->isLvalue(getContext()) == Expr::LV_Valid) {
1693    if (int Cond = ConstantFoldsToSimpleInteger(E->getCond())) {
1694      Expr *Live = Cond == 1 ? E->getLHS() : E->getRHS();
1695      if (Live)
1696        return EmitLValue(Live);
1697    }
1698
1699    if (!E->getLHS())
1700      return EmitUnsupportedLValue(E, "conditional operator with missing LHS");
1701
1702    llvm::BasicBlock *LHSBlock = createBasicBlock("cond.true");
1703    llvm::BasicBlock *RHSBlock = createBasicBlock("cond.false");
1704    llvm::BasicBlock *ContBlock = createBasicBlock("cond.end");
1705
1706    EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock);
1707
1708    // Any temporaries created here are conditional.
1709    BeginConditionalBranch();
1710    EmitBlock(LHSBlock);
1711    LValue LHS = EmitLValue(E->getLHS());
1712    EndConditionalBranch();
1713
1714    if (!LHS.isSimple())
1715      return EmitUnsupportedLValue(E, "conditional operator");
1716
1717    // FIXME: We shouldn't need an alloca for this.
1718    llvm::Value *Temp = CreateTempAlloca(LHS.getAddress()->getType(),"condtmp");
1719    Builder.CreateStore(LHS.getAddress(), Temp);
1720    EmitBranch(ContBlock);
1721
1722    // Any temporaries created here are conditional.
1723    BeginConditionalBranch();
1724    EmitBlock(RHSBlock);
1725    LValue RHS = EmitLValue(E->getRHS());
1726    EndConditionalBranch();
1727    if (!RHS.isSimple())
1728      return EmitUnsupportedLValue(E, "conditional operator");
1729
1730    Builder.CreateStore(RHS.getAddress(), Temp);
1731    EmitBranch(ContBlock);
1732
1733    EmitBlock(ContBlock);
1734
1735    Temp = Builder.CreateLoad(Temp, "lv");
1736    return MakeAddrLValue(Temp, E->getType());
1737  }
1738
1739  // ?: here should be an aggregate.
1740  assert((hasAggregateLLVMType(E->getType()) &&
1741          !E->getType()->isAnyComplexType()) &&
1742         "Unexpected conditional operator!");
1743
1744  return EmitAggExprToLValue(E);
1745}
1746
1747/// EmitCastLValue - Casts are never lvalues unless that cast is a dynamic_cast.
1748/// If the cast is a dynamic_cast, we can have the usual lvalue result,
1749/// otherwise if a cast is needed by the code generator in an lvalue context,
1750/// then it must mean that we need the address of an aggregate in order to
1751/// access one of its fields.  This can happen for all the reasons that casts
1752/// are permitted with aggregate result, including noop aggregate casts, and
1753/// cast from scalar to union.
1754LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
1755  switch (E->getCastKind()) {
1756  case CastExpr::CK_ToVoid:
1757    return EmitUnsupportedLValue(E, "unexpected cast lvalue");
1758
1759  case CastExpr::CK_NoOp:
1760    if (E->getSubExpr()->Classify(getContext()).getKind()
1761                                          != Expr::Classification::CL_PRValue) {
1762      LValue LV = EmitLValue(E->getSubExpr());
1763      if (LV.isPropertyRef()) {
1764        QualType QT = E->getSubExpr()->getType();
1765        RValue RV = EmitLoadOfPropertyRefLValue(LV, QT);
1766        assert(!RV.isScalar() && "EmitCastLValue-scalar cast of property ref");
1767        llvm::Value *V = RV.getAggregateAddr();
1768        return MakeAddrLValue(V, QT);
1769      }
1770      return LV;
1771    }
1772    // Fall through to synthesize a temporary.
1773
1774  case CastExpr::CK_Unknown:
1775  case CastExpr::CK_BitCast:
1776  case CastExpr::CK_ArrayToPointerDecay:
1777  case CastExpr::CK_FunctionToPointerDecay:
1778  case CastExpr::CK_NullToMemberPointer:
1779  case CastExpr::CK_IntegralToPointer:
1780  case CastExpr::CK_PointerToIntegral:
1781  case CastExpr::CK_VectorSplat:
1782  case CastExpr::CK_IntegralCast:
1783  case CastExpr::CK_IntegralToFloating:
1784  case CastExpr::CK_FloatingToIntegral:
1785  case CastExpr::CK_FloatingCast:
1786  case CastExpr::CK_DerivedToBaseMemberPointer:
1787  case CastExpr::CK_BaseToDerivedMemberPointer:
1788  case CastExpr::CK_MemberPointerToBoolean:
1789  case CastExpr::CK_AnyPointerToBlockPointerCast: {
1790    // These casts only produce lvalues when we're binding a reference to a
1791    // temporary realized from a (converted) pure rvalue. Emit the expression
1792    // as a value, copy it into a temporary, and return an lvalue referring to
1793    // that temporary.
1794    llvm::Value *V = CreateMemTemp(E->getType(), "ref.temp");
1795    EmitAnyExprToMem(E, V, false, false);
1796    return MakeAddrLValue(V, E->getType());
1797  }
1798
1799  case CastExpr::CK_Dynamic: {
1800    LValue LV = EmitLValue(E->getSubExpr());
1801    llvm::Value *V = LV.getAddress();
1802    const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(E);
1803    return MakeAddrLValue(EmitDynamicCast(V, DCE), E->getType());
1804  }
1805
1806  case CastExpr::CK_ConstructorConversion:
1807  case CastExpr::CK_UserDefinedConversion:
1808  case CastExpr::CK_AnyPointerToObjCPointerCast:
1809    return EmitLValue(E->getSubExpr());
1810
1811  case CastExpr::CK_UncheckedDerivedToBase:
1812  case CastExpr::CK_DerivedToBase: {
1813    const RecordType *DerivedClassTy =
1814      E->getSubExpr()->getType()->getAs<RecordType>();
1815    CXXRecordDecl *DerivedClassDecl =
1816      cast<CXXRecordDecl>(DerivedClassTy->getDecl());
1817
1818    LValue LV = EmitLValue(E->getSubExpr());
1819    llvm::Value *This;
1820    if (LV.isPropertyRef()) {
1821      RValue RV = EmitLoadOfPropertyRefLValue(LV, E->getSubExpr()->getType());
1822      assert (!RV.isScalar() && "EmitCastLValue");
1823      This = RV.getAggregateAddr();
1824    }
1825    else
1826      This = LV.getAddress();
1827
1828    // Perform the derived-to-base conversion
1829    llvm::Value *Base =
1830      GetAddressOfBaseClass(This, DerivedClassDecl,
1831                            E->path_begin(), E->path_end(),
1832                            /*NullCheckValue=*/false);
1833
1834    return MakeAddrLValue(Base, E->getType());
1835  }
1836  case CastExpr::CK_ToUnion:
1837    return EmitAggExprToLValue(E);
1838  case CastExpr::CK_BaseToDerived: {
1839    const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
1840    CXXRecordDecl *DerivedClassDecl =
1841      cast<CXXRecordDecl>(DerivedClassTy->getDecl());
1842
1843    LValue LV = EmitLValue(E->getSubExpr());
1844
1845    // Perform the base-to-derived conversion
1846    llvm::Value *Derived =
1847      GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
1848                               E->path_begin(), E->path_end(),
1849                               /*NullCheckValue=*/false);
1850
1851    return MakeAddrLValue(Derived, E->getType());
1852  }
1853  case CastExpr::CK_LValueBitCast: {
1854    // This must be a reinterpret_cast (or c-style equivalent).
1855    const ExplicitCastExpr *CE = cast<ExplicitCastExpr>(E);
1856
1857    LValue LV = EmitLValue(E->getSubExpr());
1858    llvm::Value *V = Builder.CreateBitCast(LV.getAddress(),
1859                                           ConvertType(CE->getTypeAsWritten()));
1860    return MakeAddrLValue(V, E->getType());
1861  }
1862  case CastExpr::CK_ObjCObjectLValueCast: {
1863    LValue LV = EmitLValue(E->getSubExpr());
1864    QualType ToType = getContext().getLValueReferenceType(E->getType());
1865    llvm::Value *V = Builder.CreateBitCast(LV.getAddress(),
1866                                           ConvertType(ToType));
1867    return MakeAddrLValue(V, E->getType());
1868  }
1869  }
1870
1871  llvm_unreachable("Unhandled lvalue cast kind?");
1872}
1873
1874LValue CodeGenFunction::EmitNullInitializationLValue(
1875                                              const CXXScalarValueInitExpr *E) {
1876  QualType Ty = E->getType();
1877  LValue LV = MakeAddrLValue(CreateMemTemp(Ty), Ty);
1878  EmitNullInitialization(LV.getAddress(), Ty);
1879  return LV;
1880}
1881
1882//===--------------------------------------------------------------------===//
1883//                             Expression Emission
1884//===--------------------------------------------------------------------===//
1885
1886
1887RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
1888                                     ReturnValueSlot ReturnValue) {
1889  // Builtins never have block type.
1890  if (E->getCallee()->getType()->isBlockPointerType())
1891    return EmitBlockCallExpr(E, ReturnValue);
1892
1893  if (const CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(E))
1894    return EmitCXXMemberCallExpr(CE, ReturnValue);
1895
1896  const Decl *TargetDecl = 0;
1897  if (const ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E->getCallee())) {
1898    if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CE->getSubExpr())) {
1899      TargetDecl = DRE->getDecl();
1900      if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(TargetDecl))
1901        if (unsigned builtinID = FD->getBuiltinID())
1902          return EmitBuiltinExpr(FD, builtinID, E);
1903    }
1904  }
1905
1906  if (const CXXOperatorCallExpr *CE = dyn_cast<CXXOperatorCallExpr>(E))
1907    if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(TargetDecl))
1908      return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
1909
1910  if (isa<CXXPseudoDestructorExpr>(E->getCallee()->IgnoreParens())) {
1911    // C++ [expr.pseudo]p1:
1912    //   The result shall only be used as the operand for the function call
1913    //   operator (), and the result of such a call has type void. The only
1914    //   effect is the evaluation of the postfix-expression before the dot or
1915    //   arrow.
1916    EmitScalarExpr(E->getCallee());
1917    return RValue::get(0);
1918  }
1919
1920  llvm::Value *Callee = EmitScalarExpr(E->getCallee());
1921  return EmitCall(E->getCallee()->getType(), Callee, ReturnValue,
1922                  E->arg_begin(), E->arg_end(), TargetDecl);
1923}
1924
1925LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
1926  // Comma expressions just emit their LHS then their RHS as an l-value.
1927  if (E->getOpcode() == BinaryOperator::Comma) {
1928    EmitAnyExpr(E->getLHS());
1929    EnsureInsertPoint();
1930    return EmitLValue(E->getRHS());
1931  }
1932
1933  if (E->getOpcode() == BinaryOperator::PtrMemD ||
1934      E->getOpcode() == BinaryOperator::PtrMemI)
1935    return EmitPointerToDataMemberBinaryExpr(E);
1936
1937  // Can only get l-value for binary operator expressions which are a
1938  // simple assignment of aggregate type.
1939  if (E->getOpcode() != BinaryOperator::Assign)
1940    return EmitUnsupportedLValue(E, "binary l-value expression");
1941
1942  if (!hasAggregateLLVMType(E->getType())) {
1943    // Emit the LHS as an l-value.
1944    LValue LV = EmitLValue(E->getLHS());
1945    // Store the value through the l-value.
1946    EmitStoreThroughLValue(EmitAnyExpr(E->getRHS()), LV, E->getType());
1947    return LV;
1948  }
1949
1950  return EmitAggExprToLValue(E);
1951}
1952
1953LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
1954  RValue RV = EmitCallExpr(E);
1955
1956  if (!RV.isScalar())
1957    return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
1958
1959  assert(E->getCallReturnType()->isReferenceType() &&
1960         "Can't have a scalar return unless the return type is a "
1961         "reference type!");
1962
1963  return MakeAddrLValue(RV.getScalarVal(), E->getType());
1964}
1965
1966LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
1967  // FIXME: This shouldn't require another copy.
1968  return EmitAggExprToLValue(E);
1969}
1970
1971LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
1972  llvm::Value *Temp = CreateMemTemp(E->getType(), "tmp");
1973  EmitCXXConstructExpr(Temp, E);
1974  return MakeAddrLValue(Temp, E->getType());
1975}
1976
1977LValue
1978CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
1979  return MakeAddrLValue(EmitCXXTypeidExpr(E), E->getType());
1980}
1981
1982LValue
1983CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
1984  LValue LV = EmitLValue(E->getSubExpr());
1985  EmitCXXTemporary(E->getTemporary(), LV.getAddress());
1986  return LV;
1987}
1988
1989LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
1990  RValue RV = EmitObjCMessageExpr(E);
1991
1992  if (!RV.isScalar())
1993    return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
1994
1995  assert(E->getMethodDecl()->getResultType()->isReferenceType() &&
1996         "Can't have a scalar return unless the return type is a "
1997         "reference type!");
1998
1999  return MakeAddrLValue(RV.getScalarVal(), E->getType());
2000}
2001
2002LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
2003  llvm::Value *V =
2004    CGM.getObjCRuntime().GetSelector(Builder, E->getSelector(), true);
2005  return MakeAddrLValue(V, E->getType());
2006}
2007
2008llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
2009                                             const ObjCIvarDecl *Ivar) {
2010  return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
2011}
2012
2013LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
2014                                          llvm::Value *BaseValue,
2015                                          const ObjCIvarDecl *Ivar,
2016                                          unsigned CVRQualifiers) {
2017  return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
2018                                                   Ivar, CVRQualifiers);
2019}
2020
2021LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
2022  // FIXME: A lot of the code below could be shared with EmitMemberExpr.
2023  llvm::Value *BaseValue = 0;
2024  const Expr *BaseExpr = E->getBase();
2025  Qualifiers BaseQuals;
2026  QualType ObjectTy;
2027  if (E->isArrow()) {
2028    BaseValue = EmitScalarExpr(BaseExpr);
2029    ObjectTy = BaseExpr->getType()->getPointeeType();
2030    BaseQuals = ObjectTy.getQualifiers();
2031  } else {
2032    LValue BaseLV = EmitLValue(BaseExpr);
2033    // FIXME: this isn't right for bitfields.
2034    BaseValue = BaseLV.getAddress();
2035    ObjectTy = BaseExpr->getType();
2036    BaseQuals = ObjectTy.getQualifiers();
2037  }
2038
2039  LValue LV =
2040    EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
2041                      BaseQuals.getCVRQualifiers());
2042  setObjCGCLValueClass(getContext(), E, LV);
2043  return LV;
2044}
2045
2046LValue
2047CodeGenFunction::EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E) {
2048  // This is a special l-value that just issues sends when we load or store
2049  // through it.
2050  return LValue::MakePropertyRef(E, E->getType().getCVRQualifiers());
2051}
2052
2053LValue CodeGenFunction::EmitObjCKVCRefLValue(
2054                                const ObjCImplicitSetterGetterRefExpr *E) {
2055  // This is a special l-value that just issues sends when we load or store
2056  // through it.
2057  return LValue::MakeKVCRef(E, E->getType().getCVRQualifiers());
2058}
2059
2060LValue CodeGenFunction::EmitObjCSuperExprLValue(const ObjCSuperExpr *E) {
2061  return EmitUnsupportedLValue(E, "use of super");
2062}
2063
2064LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
2065  // Can only get l-value for message expression returning aggregate type
2066  RValue RV = EmitAnyExprToTemp(E);
2067  return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
2068}
2069
2070RValue CodeGenFunction::EmitCall(QualType CalleeType, llvm::Value *Callee,
2071                                 ReturnValueSlot ReturnValue,
2072                                 CallExpr::const_arg_iterator ArgBeg,
2073                                 CallExpr::const_arg_iterator ArgEnd,
2074                                 const Decl *TargetDecl) {
2075  // Get the actual function type. The callee type will always be a pointer to
2076  // function type or a block pointer type.
2077  assert(CalleeType->isFunctionPointerType() &&
2078         "Call must have function pointer type!");
2079
2080  CalleeType = getContext().getCanonicalType(CalleeType);
2081
2082  const FunctionType *FnType
2083    = cast<FunctionType>(cast<PointerType>(CalleeType)->getPointeeType());
2084  QualType ResultType = FnType->getResultType();
2085
2086  CallArgList Args;
2087  EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), ArgBeg, ArgEnd);
2088
2089  return EmitCall(CGM.getTypes().getFunctionInfo(Args, FnType),
2090                  Callee, ReturnValue, Args, TargetDecl);
2091}
2092
2093LValue CodeGenFunction::
2094EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
2095  llvm::Value *BaseV;
2096  if (E->getOpcode() == BinaryOperator::PtrMemI)
2097    BaseV = EmitScalarExpr(E->getLHS());
2098  else
2099    BaseV = EmitLValue(E->getLHS()).getAddress();
2100  const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(getLLVMContext());
2101  BaseV = Builder.CreateBitCast(BaseV, i8Ty);
2102  llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
2103  llvm::Value *AddV = Builder.CreateInBoundsGEP(BaseV, OffsetV, "add.ptr");
2104
2105  QualType Ty = E->getRHS()->getType();
2106  Ty = Ty->getAs<MemberPointerType>()->getPointeeType();
2107
2108  const llvm::Type *PType = ConvertType(getContext().getPointerType(Ty));
2109  AddV = Builder.CreateBitCast(AddV, PType);
2110  return MakeAddrLValue(AddV, Ty);
2111}
2112
2113