CGExpr.cpp revision 6c552c1d5f47fbba00e6268d96a26ad026f2da2a 
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 = LValue::MakeAddr(Location, MakeQualifiers(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 CXXBaseSpecifierArray *BasePath;
146      const CXXRecordDecl *DerivedClass;
147    } DerivedToBase;
148
149    struct {
150      FieldDecl *Field;
151      unsigned CVRQualifiers;
152    } Field;
153  };
154
155  SubobjectAdjustment(const CXXBaseSpecifierArray *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->getBasePath(),
240                                                    Derived));
241          continue;
242        }
243
244        if (CE->getCastKind() == CastExpr::CK_NoOp) {
245          E = CE->getSubExpr();
246          continue;
247        }
248      } else if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
249        if (ME->getBase()->isLvalue(CGF.getContext()) != Expr::LV_Valid &&
250            ME->getBase()->getType()->isRecordType()) {
251          if (FieldDecl *Field = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
252            E = ME->getBase();
253            Adjustments.push_back(SubobjectAdjustment(Field,
254                                              E->getType().getCVRQualifiers()));
255            continue;
256          }
257        }
258      }
259
260      // Nothing changed.
261      break;
262    }
263
264    // Create a reference temporary if necessary.
265    if (CGF.hasAggregateLLVMType(E->getType()) &&
266        !E->getType()->isAnyComplexType())
267      ReferenceTemporary = CreateReferenceTemporary(CGF, E->getType(),
268                                                    InitializedDecl);
269
270    RV = CGF.EmitAnyExpr(E, ReferenceTemporary, /*IsAggLocVolatile=*/false,
271                         /*IgnoreResult=*/false, InitializedDecl);
272
273    if (InitializedDecl) {
274      // Get the destructor for the reference temporary.
275      if (const RecordType *RT = E->getType()->getAs<RecordType>()) {
276        CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
277        if (!ClassDecl->hasTrivialDestructor())
278          ReferenceTemporaryDtor = ClassDecl->getDestructor();
279      }
280    }
281
282    // Check if need to perform derived-to-base casts and/or field accesses, to
283    // get from the temporary object we created (and, potentially, for which we
284    // extended the lifetime) to the subobject we're binding the reference to.
285    if (!Adjustments.empty()) {
286      llvm::Value *Object = RV.getAggregateAddr();
287      for (unsigned I = Adjustments.size(); I != 0; --I) {
288        SubobjectAdjustment &Adjustment = Adjustments[I-1];
289        switch (Adjustment.Kind) {
290        case SubobjectAdjustment::DerivedToBaseAdjustment:
291          Object =
292              CGF.GetAddressOfBaseClass(Object,
293                                        Adjustment.DerivedToBase.DerivedClass,
294                                        *Adjustment.DerivedToBase.BasePath,
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  if (RV.isScalar())
334    CGF.EmitStoreOfScalar(RV.getScalarVal(), ReferenceTemporary,
335                          /*Volatile=*/false, E->getType());
336  else
337    CGF.StoreComplexToAddr(RV.getComplexVal(), ReferenceTemporary,
338                           /*Volatile=*/false);
339  return ReferenceTemporary;
340}
341
342RValue
343CodeGenFunction::EmitReferenceBindingToExpr(const Expr* E,
344                                            const NamedDecl *InitializedDecl) {
345  llvm::Value *ReferenceTemporary = 0;
346  const CXXDestructorDecl *ReferenceTemporaryDtor = 0;
347  llvm::Value *Value = EmitExprForReferenceBinding(*this, E, ReferenceTemporary,
348                                                   ReferenceTemporaryDtor,
349                                                   InitializedDecl);
350
351  if (!ReferenceTemporaryDtor)
352    return RValue::get(Value);
353
354  // Make sure to call the destructor for the reference temporary.
355  if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(InitializedDecl)) {
356    if (VD->hasGlobalStorage()) {
357      llvm::Constant *DtorFn =
358        CGM.GetAddrOfCXXDestructor(ReferenceTemporaryDtor, Dtor_Complete);
359      CGF.EmitCXXGlobalDtorRegistration(DtorFn,
360                                      cast<llvm::Constant>(ReferenceTemporary));
361
362      return RValue::get(Value);
363    }
364  }
365
366  CleanupBlock Cleanup(*this, NormalCleanup);
367  EmitCXXDestructorCall(ReferenceTemporaryDtor, Dtor_Complete,
368                        /*ForVirtualBase=*/false, ReferenceTemporary);
369
370  if (Exceptions) {
371    Cleanup.beginEHCleanup();
372    EmitCXXDestructorCall(ReferenceTemporaryDtor, Dtor_Complete,
373                          /*ForVirtualBase=*/false, ReferenceTemporary);
374  }
375
376  return RValue::get(Value);
377}
378
379
380/// getAccessedFieldNo - Given an encoded value and a result number, return the
381/// input field number being accessed.
382unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
383                                             const llvm::Constant *Elts) {
384  if (isa<llvm::ConstantAggregateZero>(Elts))
385    return 0;
386
387  return cast<llvm::ConstantInt>(Elts->getOperand(Idx))->getZExtValue();
388}
389
390void CodeGenFunction::EmitCheck(llvm::Value *Address, unsigned Size) {
391  if (!CatchUndefined)
392    return;
393
394  Address = Builder.CreateBitCast(Address, PtrToInt8Ty);
395
396  const llvm::Type *IntPtrT = IntPtrTy;
397  llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, &IntPtrT, 1);
398  const llvm::IntegerType *Int1Ty = llvm::Type::getInt1Ty(VMContext);
399
400  // In time, people may want to control this and use a 1 here.
401  llvm::Value *Arg = llvm::ConstantInt::get(Int1Ty, 0);
402  llvm::Value *C = Builder.CreateCall2(F, Address, Arg);
403  llvm::BasicBlock *Cont = createBasicBlock();
404  llvm::BasicBlock *Check = createBasicBlock();
405  llvm::Value *NegativeOne = llvm::ConstantInt::get(IntPtrTy, -1ULL);
406  Builder.CreateCondBr(Builder.CreateICmpEQ(C, NegativeOne), Cont, Check);
407
408  EmitBlock(Check);
409  Builder.CreateCondBr(Builder.CreateICmpUGE(C,
410                                        llvm::ConstantInt::get(IntPtrTy, Size)),
411                       Cont, getTrapBB());
412  EmitBlock(Cont);
413}
414
415
416CodeGenFunction::ComplexPairTy CodeGenFunction::
417EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
418                         bool isInc, bool isPre) {
419  ComplexPairTy InVal = LoadComplexFromAddr(LV.getAddress(),
420                                            LV.isVolatileQualified());
421
422  llvm::Value *NextVal;
423  if (isa<llvm::IntegerType>(InVal.first->getType())) {
424    uint64_t AmountVal = isInc ? 1 : -1;
425    NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
426
427    // Add the inc/dec to the real part.
428    NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
429  } else {
430    QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
431    llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
432    if (!isInc)
433      FVal.changeSign();
434    NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
435
436    // Add the inc/dec to the real part.
437    NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
438  }
439
440  ComplexPairTy IncVal(NextVal, InVal.second);
441
442  // Store the updated result through the lvalue.
443  StoreComplexToAddr(IncVal, LV.getAddress(), LV.isVolatileQualified());
444
445  // If this is a postinc, return the value read from memory, otherwise use the
446  // updated value.
447  return isPre ? IncVal : InVal;
448}
449
450
451//===----------------------------------------------------------------------===//
452//                         LValue Expression Emission
453//===----------------------------------------------------------------------===//
454
455RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
456  if (Ty->isVoidType())
457    return RValue::get(0);
458
459  if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
460    const llvm::Type *EltTy = ConvertType(CTy->getElementType());
461    llvm::Value *U = llvm::UndefValue::get(EltTy);
462    return RValue::getComplex(std::make_pair(U, U));
463  }
464
465  if (hasAggregateLLVMType(Ty)) {
466    const llvm::Type *LTy = llvm::PointerType::getUnqual(ConvertType(Ty));
467    return RValue::getAggregate(llvm::UndefValue::get(LTy));
468  }
469
470  return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
471}
472
473RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
474                                              const char *Name) {
475  ErrorUnsupported(E, Name);
476  return GetUndefRValue(E->getType());
477}
478
479LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
480                                              const char *Name) {
481  ErrorUnsupported(E, Name);
482  llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
483  return LValue::MakeAddr(llvm::UndefValue::get(Ty),
484                          MakeQualifiers(E->getType()));
485}
486
487LValue CodeGenFunction::EmitCheckedLValue(const Expr *E) {
488  LValue LV = EmitLValue(E);
489  if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple())
490    EmitCheck(LV.getAddress(), getContext().getTypeSize(E->getType()) / 8);
491  return LV;
492}
493
494/// EmitLValue - Emit code to compute a designator that specifies the location
495/// of the expression.
496///
497/// This can return one of two things: a simple address or a bitfield reference.
498/// In either case, the LLVM Value* in the LValue structure is guaranteed to be
499/// an LLVM pointer type.
500///
501/// If this returns a bitfield reference, nothing about the pointee type of the
502/// LLVM value is known: For example, it may not be a pointer to an integer.
503///
504/// If this returns a normal address, and if the lvalue's C type is fixed size,
505/// this method guarantees that the returned pointer type will point to an LLVM
506/// type of the same size of the lvalue's type.  If the lvalue has a variable
507/// length type, this is not possible.
508///
509LValue CodeGenFunction::EmitLValue(const Expr *E) {
510  switch (E->getStmtClass()) {
511  default: return EmitUnsupportedLValue(E, "l-value expression");
512
513  case Expr::ObjCSelectorExprClass:
514  return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
515  case Expr::ObjCIsaExprClass:
516    return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
517  case Expr::BinaryOperatorClass:
518    return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
519  case Expr::CompoundAssignOperatorClass:
520    return EmitCompoundAssignOperatorLValue(cast<CompoundAssignOperator>(E));
521  case Expr::CallExprClass:
522  case Expr::CXXMemberCallExprClass:
523  case Expr::CXXOperatorCallExprClass:
524    return EmitCallExprLValue(cast<CallExpr>(E));
525  case Expr::VAArgExprClass:
526    return EmitVAArgExprLValue(cast<VAArgExpr>(E));
527  case Expr::DeclRefExprClass:
528    return EmitDeclRefLValue(cast<DeclRefExpr>(E));
529  case Expr::ParenExprClass:return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
530  case Expr::PredefinedExprClass:
531    return EmitPredefinedLValue(cast<PredefinedExpr>(E));
532  case Expr::StringLiteralClass:
533    return EmitStringLiteralLValue(cast<StringLiteral>(E));
534  case Expr::ObjCEncodeExprClass:
535    return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
536
537  case Expr::BlockDeclRefExprClass:
538    return EmitBlockDeclRefLValue(cast<BlockDeclRefExpr>(E));
539
540  case Expr::CXXTemporaryObjectExprClass:
541  case Expr::CXXConstructExprClass:
542    return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
543  case Expr::CXXBindTemporaryExprClass:
544    return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
545  case Expr::CXXExprWithTemporariesClass:
546    return EmitCXXExprWithTemporariesLValue(cast<CXXExprWithTemporaries>(E));
547  case Expr::CXXScalarValueInitExprClass:
548    return EmitNullInitializationLValue(cast<CXXScalarValueInitExpr>(E));
549  case Expr::CXXDefaultArgExprClass:
550    return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr());
551  case Expr::CXXTypeidExprClass:
552    return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
553
554  case Expr::ObjCMessageExprClass:
555    return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
556  case Expr::ObjCIvarRefExprClass:
557    return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
558  case Expr::ObjCPropertyRefExprClass:
559    return EmitObjCPropertyRefLValue(cast<ObjCPropertyRefExpr>(E));
560  case Expr::ObjCImplicitSetterGetterRefExprClass:
561    return EmitObjCKVCRefLValue(cast<ObjCImplicitSetterGetterRefExpr>(E));
562  case Expr::ObjCSuperExprClass:
563    return EmitObjCSuperExprLValue(cast<ObjCSuperExpr>(E));
564
565  case Expr::StmtExprClass:
566    return EmitStmtExprLValue(cast<StmtExpr>(E));
567  case Expr::UnaryOperatorClass:
568    return EmitUnaryOpLValue(cast<UnaryOperator>(E));
569  case Expr::ArraySubscriptExprClass:
570    return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
571  case Expr::ExtVectorElementExprClass:
572    return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
573  case Expr::MemberExprClass:
574    return EmitMemberExpr(cast<MemberExpr>(E));
575  case Expr::CompoundLiteralExprClass:
576    return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
577  case Expr::ConditionalOperatorClass:
578    return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
579  case Expr::ChooseExprClass:
580    return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(getContext()));
581  case Expr::ImplicitCastExprClass:
582  case Expr::CStyleCastExprClass:
583  case Expr::CXXFunctionalCastExprClass:
584  case Expr::CXXStaticCastExprClass:
585  case Expr::CXXDynamicCastExprClass:
586  case Expr::CXXReinterpretCastExprClass:
587  case Expr::CXXConstCastExprClass:
588    return EmitCastLValue(cast<CastExpr>(E));
589  }
590}
591
592llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile,
593                                               QualType Ty) {
594  llvm::LoadInst *Load = Builder.CreateLoad(Addr, "tmp");
595  if (Volatile)
596    Load->setVolatile(true);
597
598  // Bool can have different representation in memory than in registers.
599  llvm::Value *V = Load;
600  if (Ty->isBooleanType())
601    if (V->getType() != llvm::Type::getInt1Ty(VMContext))
602      V = Builder.CreateTrunc(V, llvm::Type::getInt1Ty(VMContext), "tobool");
603
604  return V;
605}
606
607void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr,
608                                        bool Volatile, QualType Ty) {
609
610  if (Ty->isBooleanType()) {
611    // Bool can have different representation in memory than in registers.
612    const llvm::PointerType *DstPtr = cast<llvm::PointerType>(Addr->getType());
613    Value = Builder.CreateIntCast(Value, DstPtr->getElementType(), false);
614  }
615  Builder.CreateStore(Value, Addr, Volatile);
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                                          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    else
842      CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
843    return;
844  }
845
846  assert(Src.isScalar() && "Can't emit an agg store with this method");
847  EmitStoreOfScalar(Src.getScalarVal(), Dst.getAddress(),
848                    Dst.isVolatileQualified(), Ty);
849}
850
851void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
852                                                     QualType Ty,
853                                                     llvm::Value **Result) {
854  const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
855
856  // Get the output type.
857  const llvm::Type *ResLTy = ConvertTypeForMem(Ty);
858  unsigned ResSizeInBits = CGM.getTargetData().getTypeSizeInBits(ResLTy);
859
860  // Get the source value, truncated to the width of the bit-field.
861  llvm::Value *SrcVal = Src.getScalarVal();
862
863  if (Ty->isBooleanType())
864    SrcVal = Builder.CreateIntCast(SrcVal, ResLTy, /*IsSigned=*/false);
865
866  SrcVal = Builder.CreateAnd(SrcVal, llvm::APInt::getLowBitsSet(ResSizeInBits,
867                                                                Info.getSize()),
868                             "bf.value");
869
870  // Return the new value of the bit-field, if requested.
871  if (Result) {
872    // Cast back to the proper type for result.
873    const llvm::Type *SrcTy = Src.getScalarVal()->getType();
874    llvm::Value *ReloadVal = Builder.CreateIntCast(SrcVal, SrcTy, false,
875                                                   "bf.reload.val");
876
877    // Sign extend if necessary.
878    if (Info.isSigned()) {
879      unsigned ExtraBits = ResSizeInBits - Info.getSize();
880      if (ExtraBits)
881        ReloadVal = Builder.CreateAShr(Builder.CreateShl(ReloadVal, ExtraBits),
882                                       ExtraBits, "bf.reload.sext");
883    }
884
885    *Result = ReloadVal;
886  }
887
888  // Iterate over the components, writing each piece to memory.
889  for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) {
890    const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i);
891
892    // Get the field pointer.
893    llvm::Value *Ptr = Dst.getBitFieldBaseAddr();
894
895    // Only offset by the field index if used, so that incoming values are not
896    // required to be structures.
897    if (AI.FieldIndex)
898      Ptr = Builder.CreateStructGEP(Ptr, AI.FieldIndex, "bf.field");
899
900    // Offset by the byte offset, if used.
901    if (AI.FieldByteOffset) {
902      const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext);
903      Ptr = Builder.CreateBitCast(Ptr, i8PTy);
904      Ptr = Builder.CreateConstGEP1_32(Ptr, AI.FieldByteOffset,"bf.field.offs");
905    }
906
907    // Cast to the access type.
908    const llvm::Type *PTy = llvm::Type::getIntNPtrTy(VMContext, AI.AccessWidth,
909                                                     Ty.getAddressSpace());
910    Ptr = Builder.CreateBitCast(Ptr, PTy);
911
912    // Extract the piece of the bit-field value to write in this access, limited
913    // to the values that are part of this access.
914    llvm::Value *Val = SrcVal;
915    if (AI.TargetBitOffset)
916      Val = Builder.CreateLShr(Val, AI.TargetBitOffset);
917    Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(ResSizeInBits,
918                                                            AI.TargetBitWidth));
919
920    // Extend or truncate to the access size.
921    const llvm::Type *AccessLTy =
922      llvm::Type::getIntNTy(VMContext, AI.AccessWidth);
923    if (ResSizeInBits < AI.AccessWidth)
924      Val = Builder.CreateZExt(Val, AccessLTy);
925    else if (ResSizeInBits > AI.AccessWidth)
926      Val = Builder.CreateTrunc(Val, AccessLTy);
927
928    // Shift into the position in memory.
929    if (AI.FieldBitStart)
930      Val = Builder.CreateShl(Val, AI.FieldBitStart);
931
932    // If necessary, load and OR in bits that are outside of the bit-field.
933    if (AI.TargetBitWidth != AI.AccessWidth) {
934      llvm::LoadInst *Load = Builder.CreateLoad(Ptr, Dst.isVolatileQualified());
935      if (AI.AccessAlignment)
936        Load->setAlignment(AI.AccessAlignment);
937
938      // Compute the mask for zeroing the bits that are part of the bit-field.
939      llvm::APInt InvMask =
940        ~llvm::APInt::getBitsSet(AI.AccessWidth, AI.FieldBitStart,
941                                 AI.FieldBitStart + AI.TargetBitWidth);
942
943      // Apply the mask and OR in to the value to write.
944      Val = Builder.CreateOr(Builder.CreateAnd(Load, InvMask), Val);
945    }
946
947    // Write the value.
948    llvm::StoreInst *Store = Builder.CreateStore(Val, Ptr,
949                                                 Dst.isVolatileQualified());
950    if (AI.AccessAlignment)
951      Store->setAlignment(AI.AccessAlignment);
952  }
953}
954
955void CodeGenFunction::EmitStoreThroughPropertyRefLValue(RValue Src,
956                                                        LValue Dst,
957                                                        QualType Ty) {
958  EmitObjCPropertySet(Dst.getPropertyRefExpr(), Src);
959}
960
961void CodeGenFunction::EmitStoreThroughKVCRefLValue(RValue Src,
962                                                   LValue Dst,
963                                                   QualType Ty) {
964  EmitObjCPropertySet(Dst.getKVCRefExpr(), Src);
965}
966
967void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
968                                                               LValue Dst,
969                                                               QualType Ty) {
970  // This access turns into a read/modify/write of the vector.  Load the input
971  // value now.
972  llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddr(),
973                                        Dst.isVolatileQualified(), "tmp");
974  const llvm::Constant *Elts = Dst.getExtVectorElts();
975
976  llvm::Value *SrcVal = Src.getScalarVal();
977
978  if (const VectorType *VTy = Ty->getAs<VectorType>()) {
979    unsigned NumSrcElts = VTy->getNumElements();
980    unsigned NumDstElts =
981       cast<llvm::VectorType>(Vec->getType())->getNumElements();
982    if (NumDstElts == NumSrcElts) {
983      // Use shuffle vector is the src and destination are the same number of
984      // elements and restore the vector mask since it is on the side it will be
985      // stored.
986      llvm::SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
987      for (unsigned i = 0; i != NumSrcElts; ++i) {
988        unsigned InIdx = getAccessedFieldNo(i, Elts);
989        Mask[InIdx] = llvm::ConstantInt::get(Int32Ty, i);
990      }
991
992      llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
993      Vec = Builder.CreateShuffleVector(SrcVal,
994                                        llvm::UndefValue::get(Vec->getType()),
995                                        MaskV, "tmp");
996    } else if (NumDstElts > NumSrcElts) {
997      // Extended the source vector to the same length and then shuffle it
998      // into the destination.
999      // FIXME: since we're shuffling with undef, can we just use the indices
1000      //        into that?  This could be simpler.
1001      llvm::SmallVector<llvm::Constant*, 4> ExtMask;
1002      unsigned i;
1003      for (i = 0; i != NumSrcElts; ++i)
1004        ExtMask.push_back(llvm::ConstantInt::get(Int32Ty, i));
1005      for (; i != NumDstElts; ++i)
1006        ExtMask.push_back(llvm::UndefValue::get(Int32Ty));
1007      llvm::Value *ExtMaskV = llvm::ConstantVector::get(&ExtMask[0],
1008                                                        ExtMask.size());
1009      llvm::Value *ExtSrcVal =
1010        Builder.CreateShuffleVector(SrcVal,
1011                                    llvm::UndefValue::get(SrcVal->getType()),
1012                                    ExtMaskV, "tmp");
1013      // build identity
1014      llvm::SmallVector<llvm::Constant*, 4> Mask;
1015      for (unsigned i = 0; i != NumDstElts; ++i)
1016        Mask.push_back(llvm::ConstantInt::get(Int32Ty, i));
1017
1018      // modify when what gets shuffled in
1019      for (unsigned i = 0; i != NumSrcElts; ++i) {
1020        unsigned Idx = getAccessedFieldNo(i, Elts);
1021        Mask[Idx] = llvm::ConstantInt::get(Int32Ty, i+NumDstElts);
1022      }
1023      llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
1024      Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV, "tmp");
1025    } else {
1026      // We should never shorten the vector
1027      assert(0 && "unexpected shorten vector length");
1028    }
1029  } else {
1030    // If the Src is a scalar (not a vector) it must be updating one element.
1031    unsigned InIdx = getAccessedFieldNo(0, Elts);
1032    llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx);
1033    Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt, "tmp");
1034  }
1035
1036  Builder.CreateStore(Vec, Dst.getExtVectorAddr(), Dst.isVolatileQualified());
1037}
1038
1039// setObjCGCLValueClass - sets class of he lvalue for the purpose of
1040// generating write-barries API. It is currently a global, ivar,
1041// or neither.
1042static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
1043                                 LValue &LV) {
1044  if (Ctx.getLangOptions().getGCMode() == LangOptions::NonGC)
1045    return;
1046
1047  if (isa<ObjCIvarRefExpr>(E)) {
1048    LV.SetObjCIvar(LV, true);
1049    ObjCIvarRefExpr *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr*>(E));
1050    LV.setBaseIvarExp(Exp->getBase());
1051    LV.SetObjCArray(LV, E->getType()->isArrayType());
1052    return;
1053  }
1054
1055  if (const DeclRefExpr *Exp = dyn_cast<DeclRefExpr>(E)) {
1056    if (const VarDecl *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
1057      if ((VD->isBlockVarDecl() && !VD->hasLocalStorage()) ||
1058          VD->isFileVarDecl())
1059        LV.SetGlobalObjCRef(LV, true);
1060    }
1061    LV.SetObjCArray(LV, E->getType()->isArrayType());
1062    return;
1063  }
1064
1065  if (const UnaryOperator *Exp = dyn_cast<UnaryOperator>(E)) {
1066    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1067    return;
1068  }
1069
1070  if (const ParenExpr *Exp = dyn_cast<ParenExpr>(E)) {
1071    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1072    if (LV.isObjCIvar()) {
1073      // If cast is to a structure pointer, follow gcc's behavior and make it
1074      // a non-ivar write-barrier.
1075      QualType ExpTy = E->getType();
1076      if (ExpTy->isPointerType())
1077        ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
1078      if (ExpTy->isRecordType())
1079        LV.SetObjCIvar(LV, false);
1080    }
1081    return;
1082  }
1083  if (const ImplicitCastExpr *Exp = dyn_cast<ImplicitCastExpr>(E)) {
1084    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1085    return;
1086  }
1087
1088  if (const CStyleCastExpr *Exp = dyn_cast<CStyleCastExpr>(E)) {
1089    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
1090    return;
1091  }
1092
1093  if (const ArraySubscriptExpr *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
1094    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
1095    if (LV.isObjCIvar() && !LV.isObjCArray())
1096      // Using array syntax to assigning to what an ivar points to is not
1097      // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
1098      LV.SetObjCIvar(LV, false);
1099    else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
1100      // Using array syntax to assigning to what global points to is not
1101      // same as assigning to the global itself. {id *G;} G[i] = 0;
1102      LV.SetGlobalObjCRef(LV, false);
1103    return;
1104  }
1105
1106  if (const MemberExpr *Exp = dyn_cast<MemberExpr>(E)) {
1107    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
1108    // We don't know if member is an 'ivar', but this flag is looked at
1109    // only in the context of LV.isObjCIvar().
1110    LV.SetObjCArray(LV, E->getType()->isArrayType());
1111    return;
1112  }
1113}
1114
1115static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
1116                                      const Expr *E, const VarDecl *VD) {
1117  assert((VD->hasExternalStorage() || VD->isFileVarDecl()) &&
1118         "Var decl must have external storage or be a file var decl!");
1119
1120  llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
1121  if (VD->getType()->isReferenceType())
1122    V = CGF.Builder.CreateLoad(V, "tmp");
1123  LValue LV = LValue::MakeAddr(V, CGF.MakeQualifiers(E->getType()));
1124  setObjCGCLValueClass(CGF.getContext(), E, LV);
1125  return LV;
1126}
1127
1128static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
1129                                      const Expr *E, const FunctionDecl *FD) {
1130  llvm::Value* V = CGF.CGM.GetAddrOfFunction(FD);
1131  if (!FD->hasPrototype()) {
1132    if (const FunctionProtoType *Proto =
1133            FD->getType()->getAs<FunctionProtoType>()) {
1134      // Ugly case: for a K&R-style definition, the type of the definition
1135      // isn't the same as the type of a use.  Correct for this with a
1136      // bitcast.
1137      QualType NoProtoType =
1138          CGF.getContext().getFunctionNoProtoType(Proto->getResultType());
1139      NoProtoType = CGF.getContext().getPointerType(NoProtoType);
1140      V = CGF.Builder.CreateBitCast(V, CGF.ConvertType(NoProtoType), "tmp");
1141    }
1142  }
1143  return LValue::MakeAddr(V, CGF.MakeQualifiers(E->getType()));
1144}
1145
1146LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
1147  const NamedDecl *ND = E->getDecl();
1148
1149  if (ND->hasAttr<WeakRefAttr>()) {
1150    const ValueDecl* VD = cast<ValueDecl>(ND);
1151    llvm::Constant *Aliasee = CGM.GetWeakRefReference(VD);
1152
1153    Qualifiers Quals = MakeQualifiers(E->getType());
1154    LValue LV = LValue::MakeAddr(Aliasee, Quals);
1155
1156    return LV;
1157  }
1158
1159  if (const VarDecl *VD = dyn_cast<VarDecl>(ND)) {
1160
1161    // Check if this is a global variable.
1162    if (VD->hasExternalStorage() || VD->isFileVarDecl())
1163      return EmitGlobalVarDeclLValue(*this, E, VD);
1164
1165    bool NonGCable = VD->hasLocalStorage() && !VD->hasAttr<BlocksAttr>();
1166
1167    llvm::Value *V = LocalDeclMap[VD];
1168    if (!V && getContext().getLangOptions().CPlusPlus &&
1169        VD->isStaticLocal())
1170      V = CGM.getStaticLocalDeclAddress(VD);
1171    assert(V && "DeclRefExpr not entered in LocalDeclMap?");
1172
1173    Qualifiers Quals = MakeQualifiers(E->getType());
1174    // local variables do not get their gc attribute set.
1175    // local static?
1176    if (NonGCable) Quals.removeObjCGCAttr();
1177
1178    if (VD->hasAttr<BlocksAttr>()) {
1179      V = Builder.CreateStructGEP(V, 1, "forwarding");
1180      V = Builder.CreateLoad(V);
1181      V = Builder.CreateStructGEP(V, getByRefValueLLVMField(VD),
1182                                  VD->getNameAsString());
1183    }
1184    if (VD->getType()->isReferenceType())
1185      V = Builder.CreateLoad(V, "tmp");
1186    LValue LV = LValue::MakeAddr(V, Quals);
1187    LValue::SetObjCNonGC(LV, NonGCable);
1188    setObjCGCLValueClass(getContext(), E, LV);
1189    return LV;
1190  }
1191
1192  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
1193    return EmitFunctionDeclLValue(*this, E, FD);
1194
1195  // FIXME: the qualifier check does not seem sufficient here
1196  if (E->getQualifier()) {
1197    const FieldDecl *FD = cast<FieldDecl>(ND);
1198    llvm::Value *V = CGM.EmitPointerToDataMember(FD);
1199
1200    return LValue::MakeAddr(V, MakeQualifiers(FD->getType()));
1201  }
1202
1203  assert(false && "Unhandled DeclRefExpr");
1204
1205  // an invalid LValue, but the assert will
1206  // ensure that this point is never reached.
1207  return LValue();
1208}
1209
1210LValue CodeGenFunction::EmitBlockDeclRefLValue(const BlockDeclRefExpr *E) {
1211  return LValue::MakeAddr(GetAddrOfBlockDecl(E), MakeQualifiers(E->getType()));
1212}
1213
1214LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
1215  // __extension__ doesn't affect lvalue-ness.
1216  if (E->getOpcode() == UnaryOperator::Extension)
1217    return EmitLValue(E->getSubExpr());
1218
1219  QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
1220  switch (E->getOpcode()) {
1221  default: assert(0 && "Unknown unary operator lvalue!");
1222  case UnaryOperator::Deref: {
1223    QualType T = E->getSubExpr()->getType()->getPointeeType();
1224    assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
1225
1226    Qualifiers Quals = MakeQualifiers(T);
1227    Quals.setAddressSpace(ExprTy.getAddressSpace());
1228
1229    LValue LV = LValue::MakeAddr(EmitScalarExpr(E->getSubExpr()), Quals);
1230    // We should not generate __weak write barrier on indirect reference
1231    // of a pointer to object; as in void foo (__weak id *param); *param = 0;
1232    // But, we continue to generate __strong write barrier on indirect write
1233    // into a pointer to object.
1234    if (getContext().getLangOptions().ObjC1 &&
1235        getContext().getLangOptions().getGCMode() != LangOptions::NonGC &&
1236        LV.isObjCWeak())
1237      LValue::SetObjCNonGC(LV, !E->isOBJCGCCandidate(getContext()));
1238    return LV;
1239  }
1240  case UnaryOperator::Real:
1241  case UnaryOperator::Imag: {
1242    LValue LV = EmitLValue(E->getSubExpr());
1243    unsigned Idx = E->getOpcode() == UnaryOperator::Imag;
1244    return LValue::MakeAddr(Builder.CreateStructGEP(LV.getAddress(),
1245                                                    Idx, "idx"),
1246                            MakeQualifiers(ExprTy));
1247  }
1248  case UnaryOperator::PreInc:
1249  case UnaryOperator::PreDec: {
1250    LValue LV = EmitLValue(E->getSubExpr());
1251    bool isInc = E->getOpcode() == UnaryOperator::PreInc;
1252
1253    if (E->getType()->isAnyComplexType())
1254      EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
1255    else
1256      EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
1257    return LV;
1258  }
1259  }
1260}
1261
1262LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
1263  return LValue::MakeAddr(CGM.GetAddrOfConstantStringFromLiteral(E),
1264                          Qualifiers());
1265}
1266
1267LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
1268  return LValue::MakeAddr(CGM.GetAddrOfConstantStringFromObjCEncode(E),
1269                          Qualifiers());
1270}
1271
1272
1273LValue CodeGenFunction::EmitPredefinedFunctionName(unsigned Type) {
1274  std::string GlobalVarName;
1275
1276  switch (Type) {
1277  default: assert(0 && "Invalid type");
1278  case PredefinedExpr::Func:
1279    GlobalVarName = "__func__.";
1280    break;
1281  case PredefinedExpr::Function:
1282    GlobalVarName = "__FUNCTION__.";
1283    break;
1284  case PredefinedExpr::PrettyFunction:
1285    GlobalVarName = "__PRETTY_FUNCTION__.";
1286    break;
1287  }
1288
1289  llvm::StringRef FnName = CurFn->getName();
1290  if (FnName.startswith("\01"))
1291    FnName = FnName.substr(1);
1292  GlobalVarName += FnName;
1293
1294  std::string FunctionName =
1295    PredefinedExpr::ComputeName((PredefinedExpr::IdentType)Type, CurCodeDecl);
1296
1297  llvm::Constant *C =
1298    CGM.GetAddrOfConstantCString(FunctionName, GlobalVarName.c_str());
1299  return LValue::MakeAddr(C, Qualifiers());
1300}
1301
1302LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
1303  switch (E->getIdentType()) {
1304  default:
1305    return EmitUnsupportedLValue(E, "predefined expression");
1306  case PredefinedExpr::Func:
1307  case PredefinedExpr::Function:
1308  case PredefinedExpr::PrettyFunction:
1309    return EmitPredefinedFunctionName(E->getIdentType());
1310  }
1311}
1312
1313llvm::BasicBlock *CodeGenFunction::getTrapBB() {
1314  const CodeGenOptions &GCO = CGM.getCodeGenOpts();
1315
1316  // If we are not optimzing, don't collapse all calls to trap in the function
1317  // to the same call, that way, in the debugger they can see which operation
1318  // did in fact fail.  If we are optimizing, we collapse all calls to trap down
1319  // to just one per function to save on codesize.
1320  if (GCO.OptimizationLevel && TrapBB)
1321    return TrapBB;
1322
1323  llvm::BasicBlock *Cont = 0;
1324  if (HaveInsertPoint()) {
1325    Cont = createBasicBlock("cont");
1326    EmitBranch(Cont);
1327  }
1328  TrapBB = createBasicBlock("trap");
1329  EmitBlock(TrapBB);
1330
1331  llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::trap, 0, 0);
1332  llvm::CallInst *TrapCall = Builder.CreateCall(F);
1333  TrapCall->setDoesNotReturn();
1334  TrapCall->setDoesNotThrow();
1335  Builder.CreateUnreachable();
1336
1337  if (Cont)
1338    EmitBlock(Cont);
1339  return TrapBB;
1340}
1341
1342/// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
1343/// array to pointer, return the array subexpression.
1344static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
1345  // If this isn't just an array->pointer decay, bail out.
1346  const CastExpr *CE = dyn_cast<CastExpr>(E);
1347  if (CE == 0 || CE->getCastKind() != CastExpr::CK_ArrayToPointerDecay)
1348    return 0;
1349
1350  // If this is a decay from variable width array, bail out.
1351  const Expr *SubExpr = CE->getSubExpr();
1352  if (SubExpr->getType()->isVariableArrayType())
1353    return 0;
1354
1355  return SubExpr;
1356}
1357
1358LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E) {
1359  // The index must always be an integer, which is not an aggregate.  Emit it.
1360  llvm::Value *Idx = EmitScalarExpr(E->getIdx());
1361  QualType IdxTy  = E->getIdx()->getType();
1362  bool IdxSigned = IdxTy->isSignedIntegerType();
1363
1364  // If the base is a vector type, then we are forming a vector element lvalue
1365  // with this subscript.
1366  if (E->getBase()->getType()->isVectorType()) {
1367    // Emit the vector as an lvalue to get its address.
1368    LValue LHS = EmitLValue(E->getBase());
1369    assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
1370    Idx = Builder.CreateIntCast(Idx, CGF.Int32Ty, IdxSigned, "vidx");
1371    return LValue::MakeVectorElt(LHS.getAddress(), Idx,
1372                                 E->getBase()->getType().getCVRQualifiers());
1373  }
1374
1375  // Extend or truncate the index type to 32 or 64-bits.
1376  if (!Idx->getType()->isIntegerTy(LLVMPointerWidth))
1377    Idx = Builder.CreateIntCast(Idx, IntPtrTy,
1378                                IdxSigned, "idxprom");
1379
1380  // FIXME: As llvm implements the object size checking, this can come out.
1381  if (CatchUndefined) {
1382    if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E->getBase())){
1383      if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr())) {
1384        if (ICE->getCastKind() == CastExpr::CK_ArrayToPointerDecay) {
1385          if (const ConstantArrayType *CAT
1386              = getContext().getAsConstantArrayType(DRE->getType())) {
1387            llvm::APInt Size = CAT->getSize();
1388            llvm::BasicBlock *Cont = createBasicBlock("cont");
1389            Builder.CreateCondBr(Builder.CreateICmpULE(Idx,
1390                                  llvm::ConstantInt::get(Idx->getType(), Size)),
1391                                 Cont, getTrapBB());
1392            EmitBlock(Cont);
1393          }
1394        }
1395      }
1396    }
1397  }
1398
1399  // We know that the pointer points to a type of the correct size, unless the
1400  // size is a VLA or Objective-C interface.
1401  llvm::Value *Address = 0;
1402  if (const VariableArrayType *VAT =
1403        getContext().getAsVariableArrayType(E->getType())) {
1404    llvm::Value *VLASize = GetVLASize(VAT);
1405
1406    Idx = Builder.CreateMul(Idx, VLASize);
1407
1408    QualType BaseType = getContext().getBaseElementType(VAT);
1409
1410    CharUnits BaseTypeSize = getContext().getTypeSizeInChars(BaseType);
1411    Idx = Builder.CreateUDiv(Idx,
1412                             llvm::ConstantInt::get(Idx->getType(),
1413                                 BaseTypeSize.getQuantity()));
1414
1415    // The base must be a pointer, which is not an aggregate.  Emit it.
1416    llvm::Value *Base = EmitScalarExpr(E->getBase());
1417
1418    Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
1419  } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
1420    // Indexing over an interface, as in "NSString *P; P[4];"
1421    llvm::Value *InterfaceSize =
1422      llvm::ConstantInt::get(Idx->getType(),
1423          getContext().getTypeSizeInChars(OIT).getQuantity());
1424
1425    Idx = Builder.CreateMul(Idx, InterfaceSize);
1426
1427    const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext);
1428
1429    // The base must be a pointer, which is not an aggregate.  Emit it.
1430    llvm::Value *Base = EmitScalarExpr(E->getBase());
1431    Address = Builder.CreateGEP(Builder.CreateBitCast(Base, i8PTy),
1432                                Idx, "arrayidx");
1433    Address = Builder.CreateBitCast(Address, Base->getType());
1434  } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
1435    // If this is A[i] where A is an array, the frontend will have decayed the
1436    // base to be a ArrayToPointerDecay implicit cast.  While correct, it is
1437    // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
1438    // "gep x, i" here.  Emit one "gep A, 0, i".
1439    assert(Array->getType()->isArrayType() &&
1440           "Array to pointer decay must have array source type!");
1441    llvm::Value *ArrayPtr = EmitLValue(Array).getAddress();
1442    llvm::Value *Zero = llvm::ConstantInt::get(Int32Ty, 0);
1443    llvm::Value *Args[] = { Zero, Idx };
1444
1445    Address = Builder.CreateInBoundsGEP(ArrayPtr, Args, Args+2, "arrayidx");
1446  } else {
1447    // The base must be a pointer, which is not an aggregate.  Emit it.
1448    llvm::Value *Base = EmitScalarExpr(E->getBase());
1449    Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
1450  }
1451
1452  QualType T = E->getBase()->getType()->getPointeeType();
1453  assert(!T.isNull() &&
1454         "CodeGenFunction::EmitArraySubscriptExpr(): Illegal base type");
1455
1456  Qualifiers Quals = MakeQualifiers(T);
1457  Quals.setAddressSpace(E->getBase()->getType().getAddressSpace());
1458
1459  LValue LV = LValue::MakeAddr(Address, Quals);
1460  if (getContext().getLangOptions().ObjC1 &&
1461      getContext().getLangOptions().getGCMode() != LangOptions::NonGC) {
1462    LValue::SetObjCNonGC(LV, !E->isOBJCGCCandidate(getContext()));
1463    setObjCGCLValueClass(getContext(), E, LV);
1464  }
1465  return LV;
1466}
1467
1468static
1469llvm::Constant *GenerateConstantVector(llvm::LLVMContext &VMContext,
1470                                       llvm::SmallVector<unsigned, 4> &Elts) {
1471  llvm::SmallVector<llvm::Constant*, 4> CElts;
1472
1473  const llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext);
1474  for (unsigned i = 0, e = Elts.size(); i != e; ++i)
1475    CElts.push_back(llvm::ConstantInt::get(Int32Ty, Elts[i]));
1476
1477  return llvm::ConstantVector::get(&CElts[0], CElts.size());
1478}
1479
1480LValue CodeGenFunction::
1481EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
1482  // Emit the base vector as an l-value.
1483  LValue Base;
1484
1485  // ExtVectorElementExpr's base can either be a vector or pointer to vector.
1486  if (E->isArrow()) {
1487    // If it is a pointer to a vector, emit the address and form an lvalue with
1488    // it.
1489    llvm::Value *Ptr = EmitScalarExpr(E->getBase());
1490    const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
1491    Qualifiers Quals = MakeQualifiers(PT->getPointeeType());
1492    Quals.removeObjCGCAttr();
1493    Base = LValue::MakeAddr(Ptr, Quals);
1494  } else if (E->getBase()->isLvalue(getContext()) == Expr::LV_Valid) {
1495    // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
1496    // emit the base as an lvalue.
1497    assert(E->getBase()->getType()->isVectorType());
1498    Base = EmitLValue(E->getBase());
1499  } else {
1500    // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
1501    assert(E->getBase()->getType()->getAs<VectorType>() &&
1502           "Result must be a vector");
1503    llvm::Value *Vec = EmitScalarExpr(E->getBase());
1504
1505    // Store the vector to memory (because LValue wants an address).
1506    llvm::Value *VecMem = CreateMemTemp(E->getBase()->getType());
1507    Builder.CreateStore(Vec, VecMem);
1508    Base = LValue::MakeAddr(VecMem, Qualifiers());
1509  }
1510
1511  // Encode the element access list into a vector of unsigned indices.
1512  llvm::SmallVector<unsigned, 4> Indices;
1513  E->getEncodedElementAccess(Indices);
1514
1515  if (Base.isSimple()) {
1516    llvm::Constant *CV = GenerateConstantVector(VMContext, Indices);
1517    return LValue::MakeExtVectorElt(Base.getAddress(), CV,
1518                                    Base.getVRQualifiers());
1519  }
1520  assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
1521
1522  llvm::Constant *BaseElts = Base.getExtVectorElts();
1523  llvm::SmallVector<llvm::Constant *, 4> CElts;
1524
1525  for (unsigned i = 0, e = Indices.size(); i != e; ++i) {
1526    if (isa<llvm::ConstantAggregateZero>(BaseElts))
1527      CElts.push_back(llvm::ConstantInt::get(Int32Ty, 0));
1528    else
1529      CElts.push_back(cast<llvm::Constant>(BaseElts->getOperand(Indices[i])));
1530  }
1531  llvm::Constant *CV = llvm::ConstantVector::get(&CElts[0], CElts.size());
1532  return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV,
1533                                  Base.getVRQualifiers());
1534}
1535
1536LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
1537  bool isNonGC = false;
1538  Expr *BaseExpr = E->getBase();
1539  llvm::Value *BaseValue = NULL;
1540  Qualifiers BaseQuals;
1541
1542  // If this is s.x, emit s as an lvalue.  If it is s->x, emit s as a scalar.
1543  if (E->isArrow()) {
1544    BaseValue = EmitScalarExpr(BaseExpr);
1545    const PointerType *PTy =
1546      BaseExpr->getType()->getAs<PointerType>();
1547    BaseQuals = PTy->getPointeeType().getQualifiers();
1548  } else if (isa<ObjCPropertyRefExpr>(BaseExpr->IgnoreParens()) ||
1549             isa<ObjCImplicitSetterGetterRefExpr>(
1550               BaseExpr->IgnoreParens())) {
1551    RValue RV = EmitObjCPropertyGet(BaseExpr);
1552    BaseValue = RV.getAggregateAddr();
1553    BaseQuals = BaseExpr->getType().getQualifiers();
1554  } else {
1555    LValue BaseLV = EmitLValue(BaseExpr);
1556    if (BaseLV.isNonGC())
1557      isNonGC = true;
1558    // FIXME: this isn't right for bitfields.
1559    BaseValue = BaseLV.getAddress();
1560    QualType BaseTy = BaseExpr->getType();
1561    BaseQuals = BaseTy.getQualifiers();
1562  }
1563
1564  NamedDecl *ND = E->getMemberDecl();
1565  if (FieldDecl *Field = dyn_cast<FieldDecl>(ND)) {
1566    LValue LV = EmitLValueForField(BaseValue, Field,
1567                                   BaseQuals.getCVRQualifiers());
1568    LValue::SetObjCNonGC(LV, isNonGC);
1569    setObjCGCLValueClass(getContext(), E, LV);
1570    return LV;
1571  }
1572
1573  if (VarDecl *VD = dyn_cast<VarDecl>(ND))
1574    return EmitGlobalVarDeclLValue(*this, E, VD);
1575
1576  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND))
1577    return EmitFunctionDeclLValue(*this, E, FD);
1578
1579  assert(false && "Unhandled member declaration!");
1580  return LValue();
1581}
1582
1583LValue CodeGenFunction::EmitLValueForBitfield(llvm::Value* BaseValue,
1584                                              const FieldDecl* Field,
1585                                              unsigned CVRQualifiers) {
1586  const CGRecordLayout &RL =
1587    CGM.getTypes().getCGRecordLayout(Field->getParent());
1588  const CGBitFieldInfo &Info = RL.getBitFieldInfo(Field);
1589  return LValue::MakeBitfield(BaseValue, Info,
1590                             Field->getType().getCVRQualifiers()|CVRQualifiers);
1591}
1592
1593/// EmitLValueForAnonRecordField - Given that the field is a member of
1594/// an anonymous struct or union buried inside a record, and given
1595/// that the base value is a pointer to the enclosing record, derive
1596/// an lvalue for the ultimate field.
1597LValue CodeGenFunction::EmitLValueForAnonRecordField(llvm::Value *BaseValue,
1598                                                     const FieldDecl *Field,
1599                                                     unsigned CVRQualifiers) {
1600  llvm::SmallVector<const FieldDecl *, 8> Path;
1601  Path.push_back(Field);
1602
1603  while (Field->getParent()->isAnonymousStructOrUnion()) {
1604    const ValueDecl *VD = Field->getParent()->getAnonymousStructOrUnionObject();
1605    if (!isa<FieldDecl>(VD)) break;
1606    Field = cast<FieldDecl>(VD);
1607    Path.push_back(Field);
1608  }
1609
1610  llvm::SmallVectorImpl<const FieldDecl*>::reverse_iterator
1611    I = Path.rbegin(), E = Path.rend();
1612  while (true) {
1613    LValue LV = EmitLValueForField(BaseValue, *I, CVRQualifiers);
1614    if (++I == E) return LV;
1615
1616    assert(LV.isSimple());
1617    BaseValue = LV.getAddress();
1618    CVRQualifiers |= LV.getVRQualifiers();
1619  }
1620}
1621
1622LValue CodeGenFunction::EmitLValueForField(llvm::Value* BaseValue,
1623                                           const FieldDecl* Field,
1624                                           unsigned CVRQualifiers) {
1625  if (Field->isBitField())
1626    return EmitLValueForBitfield(BaseValue, Field, CVRQualifiers);
1627
1628  const CGRecordLayout &RL =
1629    CGM.getTypes().getCGRecordLayout(Field->getParent());
1630  unsigned idx = RL.getLLVMFieldNo(Field);
1631  llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx, "tmp");
1632
1633  // Match union field type.
1634  if (Field->getParent()->isUnion()) {
1635    const llvm::Type *FieldTy =
1636      CGM.getTypes().ConvertTypeForMem(Field->getType());
1637    const llvm::PointerType * BaseTy =
1638      cast<llvm::PointerType>(BaseValue->getType());
1639    unsigned AS = BaseTy->getAddressSpace();
1640    V = Builder.CreateBitCast(V,
1641                              llvm::PointerType::get(FieldTy, AS),
1642                              "tmp");
1643  }
1644  if (Field->getType()->isReferenceType())
1645    V = Builder.CreateLoad(V, "tmp");
1646
1647  Qualifiers Quals = MakeQualifiers(Field->getType());
1648  Quals.addCVRQualifiers(CVRQualifiers);
1649  // __weak attribute on a field is ignored.
1650  if (Quals.getObjCGCAttr() == Qualifiers::Weak)
1651    Quals.removeObjCGCAttr();
1652
1653  return LValue::MakeAddr(V, Quals);
1654}
1655
1656LValue
1657CodeGenFunction::EmitLValueForFieldInitialization(llvm::Value* BaseValue,
1658                                                  const FieldDecl* Field,
1659                                                  unsigned CVRQualifiers) {
1660  QualType FieldType = Field->getType();
1661
1662  if (!FieldType->isReferenceType())
1663    return EmitLValueForField(BaseValue, Field, CVRQualifiers);
1664
1665  const CGRecordLayout &RL =
1666    CGM.getTypes().getCGRecordLayout(Field->getParent());
1667  unsigned idx = RL.getLLVMFieldNo(Field);
1668  llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx, "tmp");
1669
1670  assert(!FieldType.getObjCGCAttr() && "fields cannot have GC attrs");
1671
1672  return LValue::MakeAddr(V, MakeQualifiers(FieldType));
1673}
1674
1675LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr* E){
1676  llvm::Value *DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
1677  const Expr* InitExpr = E->getInitializer();
1678  LValue Result = LValue::MakeAddr(DeclPtr, MakeQualifiers(E->getType()));
1679
1680  EmitAnyExprToMem(InitExpr, DeclPtr, /*Volatile*/ false);
1681
1682  return Result;
1683}
1684
1685LValue
1686CodeGenFunction::EmitConditionalOperatorLValue(const ConditionalOperator* E) {
1687  if (E->isLvalue(getContext()) == Expr::LV_Valid) {
1688    if (int Cond = ConstantFoldsToSimpleInteger(E->getCond())) {
1689      Expr *Live = Cond == 1 ? E->getLHS() : E->getRHS();
1690      if (Live)
1691        return EmitLValue(Live);
1692    }
1693
1694    if (!E->getLHS())
1695      return EmitUnsupportedLValue(E, "conditional operator with missing LHS");
1696
1697    llvm::BasicBlock *LHSBlock = createBasicBlock("cond.true");
1698    llvm::BasicBlock *RHSBlock = createBasicBlock("cond.false");
1699    llvm::BasicBlock *ContBlock = createBasicBlock("cond.end");
1700
1701    EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock);
1702
1703    // Any temporaries created here are conditional.
1704    BeginConditionalBranch();
1705    EmitBlock(LHSBlock);
1706    LValue LHS = EmitLValue(E->getLHS());
1707    EndConditionalBranch();
1708
1709    if (!LHS.isSimple())
1710      return EmitUnsupportedLValue(E, "conditional operator");
1711
1712    // FIXME: We shouldn't need an alloca for this.
1713    llvm::Value *Temp = CreateTempAlloca(LHS.getAddress()->getType(),"condtmp");
1714    Builder.CreateStore(LHS.getAddress(), Temp);
1715    EmitBranch(ContBlock);
1716
1717    // Any temporaries created here are conditional.
1718    BeginConditionalBranch();
1719    EmitBlock(RHSBlock);
1720    LValue RHS = EmitLValue(E->getRHS());
1721    EndConditionalBranch();
1722    if (!RHS.isSimple())
1723      return EmitUnsupportedLValue(E, "conditional operator");
1724
1725    Builder.CreateStore(RHS.getAddress(), Temp);
1726    EmitBranch(ContBlock);
1727
1728    EmitBlock(ContBlock);
1729
1730    Temp = Builder.CreateLoad(Temp, "lv");
1731    return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1732  }
1733
1734  // ?: here should be an aggregate.
1735  assert((hasAggregateLLVMType(E->getType()) &&
1736          !E->getType()->isAnyComplexType()) &&
1737         "Unexpected conditional operator!");
1738
1739  return EmitAggExprToLValue(E);
1740}
1741
1742/// EmitCastLValue - Casts are never lvalues unless that cast is a dynamic_cast.
1743/// If the cast is a dynamic_cast, we can have the usual lvalue result,
1744/// otherwise if a cast is needed by the code generator in an lvalue context,
1745/// then it must mean that we need the address of an aggregate in order to
1746/// access one of its fields.  This can happen for all the reasons that casts
1747/// are permitted with aggregate result, including noop aggregate casts, and
1748/// cast from scalar to union.
1749LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
1750  switch (E->getCastKind()) {
1751  case CastExpr::CK_ToVoid:
1752    return EmitUnsupportedLValue(E, "unexpected cast lvalue");
1753
1754  case CastExpr::CK_NoOp:
1755    if (E->getSubExpr()->Classify(getContext()).getKind()
1756                                          != Expr::Classification::CL_PRValue) {
1757      LValue LV = EmitLValue(E->getSubExpr());
1758      if (LV.isPropertyRef()) {
1759        QualType QT = E->getSubExpr()->getType();
1760        RValue RV = EmitLoadOfPropertyRefLValue(LV, QT);
1761        assert(!RV.isScalar() && "EmitCastLValue-scalar cast of property ref");
1762        llvm::Value *V = RV.getAggregateAddr();
1763        return LValue::MakeAddr(V, MakeQualifiers(QT));
1764      }
1765      return LV;
1766    }
1767    // Fall through to synthesize a temporary.
1768
1769  case CastExpr::CK_Unknown:
1770  case CastExpr::CK_BitCast:
1771  case CastExpr::CK_ArrayToPointerDecay:
1772  case CastExpr::CK_FunctionToPointerDecay:
1773  case CastExpr::CK_NullToMemberPointer:
1774  case CastExpr::CK_IntegralToPointer:
1775  case CastExpr::CK_PointerToIntegral:
1776  case CastExpr::CK_VectorSplat:
1777  case CastExpr::CK_IntegralCast:
1778  case CastExpr::CK_IntegralToFloating:
1779  case CastExpr::CK_FloatingToIntegral:
1780  case CastExpr::CK_FloatingCast:
1781  case CastExpr::CK_DerivedToBaseMemberPointer:
1782  case CastExpr::CK_BaseToDerivedMemberPointer:
1783  case CastExpr::CK_MemberPointerToBoolean:
1784  case CastExpr::CK_AnyPointerToBlockPointerCast: {
1785    // These casts only produce lvalues when we're binding a reference to a
1786    // temporary realized from a (converted) pure rvalue. Emit the expression
1787    // as a value, copy it into a temporary, and return an lvalue referring to
1788    // that temporary.
1789    llvm::Value *V = CreateMemTemp(E->getType(), "ref.temp");
1790    EmitAnyExprToMem(E, V, false, false);
1791    return LValue::MakeAddr(V, MakeQualifiers(E->getType()));
1792  }
1793
1794  case CastExpr::CK_Dynamic: {
1795    LValue LV = EmitLValue(E->getSubExpr());
1796    llvm::Value *V = LV.getAddress();
1797    const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(E);
1798    return LValue::MakeAddr(EmitDynamicCast(V, DCE),
1799                            MakeQualifiers(E->getType()));
1800  }
1801
1802  case CastExpr::CK_ConstructorConversion:
1803  case CastExpr::CK_UserDefinedConversion:
1804  case CastExpr::CK_AnyPointerToObjCPointerCast:
1805    return EmitLValue(E->getSubExpr());
1806
1807  case CastExpr::CK_UncheckedDerivedToBase:
1808  case CastExpr::CK_DerivedToBase: {
1809    const RecordType *DerivedClassTy =
1810      E->getSubExpr()->getType()->getAs<RecordType>();
1811    CXXRecordDecl *DerivedClassDecl =
1812      cast<CXXRecordDecl>(DerivedClassTy->getDecl());
1813
1814    LValue LV = EmitLValue(E->getSubExpr());
1815    llvm::Value *This;
1816    if (LV.isPropertyRef()) {
1817      RValue RV = EmitLoadOfPropertyRefLValue(LV, E->getSubExpr()->getType());
1818      assert (!RV.isScalar() && "EmitCastLValue");
1819      This = RV.getAggregateAddr();
1820    }
1821    else
1822      This = LV.getAddress();
1823
1824    // Perform the derived-to-base conversion
1825    llvm::Value *Base =
1826      GetAddressOfBaseClass(This, DerivedClassDecl,
1827                            E->getBasePath(), /*NullCheckValue=*/false);
1828
1829    return LValue::MakeAddr(Base, MakeQualifiers(E->getType()));
1830  }
1831  case CastExpr::CK_ToUnion:
1832    return EmitAggExprToLValue(E);
1833  case CastExpr::CK_BaseToDerived: {
1834    const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
1835    CXXRecordDecl *DerivedClassDecl =
1836      cast<CXXRecordDecl>(DerivedClassTy->getDecl());
1837
1838    LValue LV = EmitLValue(E->getSubExpr());
1839
1840    // Perform the base-to-derived conversion
1841    llvm::Value *Derived =
1842      GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
1843                               E->getBasePath(),/*NullCheckValue=*/false);
1844
1845    return LValue::MakeAddr(Derived, MakeQualifiers(E->getType()));
1846  }
1847  case CastExpr::CK_LValueBitCast: {
1848    // This must be a reinterpret_cast (or c-style equivalent).
1849    const ExplicitCastExpr *CE = cast<ExplicitCastExpr>(E);
1850
1851    LValue LV = EmitLValue(E->getSubExpr());
1852    llvm::Value *V = Builder.CreateBitCast(LV.getAddress(),
1853                                           ConvertType(CE->getTypeAsWritten()));
1854    return LValue::MakeAddr(V, MakeQualifiers(E->getType()));
1855  }
1856  }
1857
1858  llvm_unreachable("Unhandled lvalue cast kind?");
1859}
1860
1861LValue CodeGenFunction::EmitNullInitializationLValue(
1862                                              const CXXScalarValueInitExpr *E) {
1863  QualType Ty = E->getType();
1864  LValue LV = LValue::MakeAddr(CreateMemTemp(Ty), MakeQualifiers(Ty));
1865  EmitNullInitialization(LV.getAddress(), Ty);
1866  return LV;
1867}
1868
1869//===--------------------------------------------------------------------===//
1870//                             Expression Emission
1871//===--------------------------------------------------------------------===//
1872
1873
1874RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
1875                                     ReturnValueSlot ReturnValue) {
1876  // Builtins never have block type.
1877  if (E->getCallee()->getType()->isBlockPointerType())
1878    return EmitBlockCallExpr(E, ReturnValue);
1879
1880  if (const CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(E))
1881    return EmitCXXMemberCallExpr(CE, ReturnValue);
1882
1883  const Decl *TargetDecl = 0;
1884  if (const ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E->getCallee())) {
1885    if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CE->getSubExpr())) {
1886      TargetDecl = DRE->getDecl();
1887      if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(TargetDecl))
1888        if (unsigned builtinID = FD->getBuiltinID())
1889          return EmitBuiltinExpr(FD, builtinID, E);
1890    }
1891  }
1892
1893  if (const CXXOperatorCallExpr *CE = dyn_cast<CXXOperatorCallExpr>(E))
1894    if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(TargetDecl))
1895      return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
1896
1897  if (isa<CXXPseudoDestructorExpr>(E->getCallee()->IgnoreParens())) {
1898    // C++ [expr.pseudo]p1:
1899    //   The result shall only be used as the operand for the function call
1900    //   operator (), and the result of such a call has type void. The only
1901    //   effect is the evaluation of the postfix-expression before the dot or
1902    //   arrow.
1903    EmitScalarExpr(E->getCallee());
1904    return RValue::get(0);
1905  }
1906
1907  llvm::Value *Callee = EmitScalarExpr(E->getCallee());
1908  return EmitCall(E->getCallee()->getType(), Callee, ReturnValue,
1909                  E->arg_begin(), E->arg_end(), TargetDecl);
1910}
1911
1912LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
1913  // Comma expressions just emit their LHS then their RHS as an l-value.
1914  if (E->getOpcode() == BinaryOperator::Comma) {
1915    EmitAnyExpr(E->getLHS());
1916    EnsureInsertPoint();
1917    return EmitLValue(E->getRHS());
1918  }
1919
1920  if (E->getOpcode() == BinaryOperator::PtrMemD ||
1921      E->getOpcode() == BinaryOperator::PtrMemI)
1922    return EmitPointerToDataMemberBinaryExpr(E);
1923
1924  // Can only get l-value for binary operator expressions which are a
1925  // simple assignment of aggregate type.
1926  if (E->getOpcode() != BinaryOperator::Assign)
1927    return EmitUnsupportedLValue(E, "binary l-value expression");
1928
1929  if (!hasAggregateLLVMType(E->getType())) {
1930    // Emit the LHS as an l-value.
1931    LValue LV = EmitLValue(E->getLHS());
1932
1933    llvm::Value *RHS = EmitScalarExpr(E->getRHS());
1934    EmitStoreOfScalar(RHS, LV.getAddress(), LV.isVolatileQualified(),
1935                      E->getType());
1936    return LV;
1937  }
1938
1939  return EmitAggExprToLValue(E);
1940}
1941
1942LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
1943  RValue RV = EmitCallExpr(E);
1944
1945  if (!RV.isScalar())
1946    return LValue::MakeAddr(RV.getAggregateAddr(),MakeQualifiers(E->getType()));
1947
1948  assert(E->getCallReturnType()->isReferenceType() &&
1949         "Can't have a scalar return unless the return type is a "
1950         "reference type!");
1951
1952  return LValue::MakeAddr(RV.getScalarVal(), MakeQualifiers(E->getType()));
1953}
1954
1955LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
1956  // FIXME: This shouldn't require another copy.
1957  return EmitAggExprToLValue(E);
1958}
1959
1960LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
1961  llvm::Value *Temp = CreateMemTemp(E->getType(), "tmp");
1962  EmitCXXConstructExpr(Temp, E);
1963  return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1964}
1965
1966LValue
1967CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
1968  llvm::Value *Temp = EmitCXXTypeidExpr(E);
1969  return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1970}
1971
1972LValue
1973CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
1974  LValue LV = EmitLValue(E->getSubExpr());
1975  EmitCXXTemporary(E->getTemporary(), LV.getAddress());
1976  return LV;
1977}
1978
1979LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
1980  RValue RV = EmitObjCMessageExpr(E);
1981
1982  if (!RV.isScalar())
1983    return LValue::MakeAddr(RV.getAggregateAddr(),
1984                            MakeQualifiers(E->getType()));
1985
1986  assert(E->getMethodDecl()->getResultType()->isReferenceType() &&
1987         "Can't have a scalar return unless the return type is a "
1988         "reference type!");
1989
1990  return LValue::MakeAddr(RV.getScalarVal(), MakeQualifiers(E->getType()));
1991}
1992
1993LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
1994  llvm::Value *V =
1995    CGM.getObjCRuntime().GetSelector(Builder, E->getSelector(), true);
1996  return LValue::MakeAddr(V, MakeQualifiers(E->getType()));
1997}
1998
1999llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
2000                                             const ObjCIvarDecl *Ivar) {
2001  return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
2002}
2003
2004LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
2005                                          llvm::Value *BaseValue,
2006                                          const ObjCIvarDecl *Ivar,
2007                                          unsigned CVRQualifiers) {
2008  return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
2009                                                   Ivar, CVRQualifiers);
2010}
2011
2012LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
2013  // FIXME: A lot of the code below could be shared with EmitMemberExpr.
2014  llvm::Value *BaseValue = 0;
2015  const Expr *BaseExpr = E->getBase();
2016  Qualifiers BaseQuals;
2017  QualType ObjectTy;
2018  if (E->isArrow()) {
2019    BaseValue = EmitScalarExpr(BaseExpr);
2020    ObjectTy = BaseExpr->getType()->getPointeeType();
2021    BaseQuals = ObjectTy.getQualifiers();
2022  } else {
2023    LValue BaseLV = EmitLValue(BaseExpr);
2024    // FIXME: this isn't right for bitfields.
2025    BaseValue = BaseLV.getAddress();
2026    ObjectTy = BaseExpr->getType();
2027    BaseQuals = ObjectTy.getQualifiers();
2028  }
2029
2030  LValue LV =
2031    EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
2032                      BaseQuals.getCVRQualifiers());
2033  setObjCGCLValueClass(getContext(), E, LV);
2034  return LV;
2035}
2036
2037LValue
2038CodeGenFunction::EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E) {
2039  // This is a special l-value that just issues sends when we load or store
2040  // through it.
2041  return LValue::MakePropertyRef(E, E->getType().getCVRQualifiers());
2042}
2043
2044LValue CodeGenFunction::EmitObjCKVCRefLValue(
2045                                const ObjCImplicitSetterGetterRefExpr *E) {
2046  // This is a special l-value that just issues sends when we load or store
2047  // through it.
2048  return LValue::MakeKVCRef(E, E->getType().getCVRQualifiers());
2049}
2050
2051LValue CodeGenFunction::EmitObjCSuperExprLValue(const ObjCSuperExpr *E) {
2052  return EmitUnsupportedLValue(E, "use of super");
2053}
2054
2055LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
2056  // Can only get l-value for message expression returning aggregate type
2057  RValue RV = EmitAnyExprToTemp(E);
2058  return LValue::MakeAddr(RV.getAggregateAddr(), MakeQualifiers(E->getType()));
2059}
2060
2061RValue CodeGenFunction::EmitCall(QualType CalleeType, llvm::Value *Callee,
2062                                 ReturnValueSlot ReturnValue,
2063                                 CallExpr::const_arg_iterator ArgBeg,
2064                                 CallExpr::const_arg_iterator ArgEnd,
2065                                 const Decl *TargetDecl) {
2066  // Get the actual function type. The callee type will always be a pointer to
2067  // function type or a block pointer type.
2068  assert(CalleeType->isFunctionPointerType() &&
2069         "Call must have function pointer type!");
2070
2071  CalleeType = getContext().getCanonicalType(CalleeType);
2072
2073  const FunctionType *FnType
2074    = cast<FunctionType>(cast<PointerType>(CalleeType)->getPointeeType());
2075  QualType ResultType = FnType->getResultType();
2076
2077  CallArgList Args;
2078  EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), ArgBeg, ArgEnd);
2079
2080  return EmitCall(CGM.getTypes().getFunctionInfo(Args, FnType),
2081                  Callee, ReturnValue, Args, TargetDecl);
2082}
2083
2084LValue CodeGenFunction::
2085EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
2086  llvm::Value *BaseV;
2087  if (E->getOpcode() == BinaryOperator::PtrMemI)
2088    BaseV = EmitScalarExpr(E->getLHS());
2089  else
2090    BaseV = EmitLValue(E->getLHS()).getAddress();
2091  const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(getLLVMContext());
2092  BaseV = Builder.CreateBitCast(BaseV, i8Ty);
2093  llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
2094  llvm::Value *AddV = Builder.CreateInBoundsGEP(BaseV, OffsetV, "add.ptr");
2095
2096  QualType Ty = E->getRHS()->getType();
2097  Ty = Ty->getAs<MemberPointerType>()->getPointeeType();
2098
2099  const llvm::Type *PType = ConvertType(getContext().getPointerType(Ty));
2100  AddV = Builder.CreateBitCast(AddV, PType);
2101  return LValue::MakeAddr(AddV, MakeQualifiers(Ty));
2102}
2103
2104