CGExpr.cpp revision 589f9e3f7845c2a1bf97ae4357aec5b457a5ea19 
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 "CGObjCRuntime.h"
18#include "clang/AST/ASTContext.h"
19#include "clang/AST/DeclObjC.h"
20#include "llvm/Target/TargetData.h"
21using namespace clang;
22using namespace CodeGen;
23
24//===--------------------------------------------------------------------===//
25//                        Miscellaneous Helper Methods
26//===--------------------------------------------------------------------===//
27
28/// CreateTempAlloca - This creates a alloca and inserts it into the entry
29/// block.
30llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(const llvm::Type *Ty,
31                                                    const llvm::Twine &Name) {
32  if (!Builder.isNamePreserving())
33    return new llvm::AllocaInst(Ty, 0, "", AllocaInsertPt);
34  return new llvm::AllocaInst(Ty, 0, Name, AllocaInsertPt);
35}
36
37/// EvaluateExprAsBool - Perform the usual unary conversions on the specified
38/// expression and compare the result against zero, returning an Int1Ty value.
39llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
40  QualType BoolTy = getContext().BoolTy;
41  if (!E->getType()->isAnyComplexType())
42    return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy);
43
44  return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(),BoolTy);
45}
46
47/// EmitAnyExpr - Emit code to compute the specified expression which can have
48/// any type.  The result is returned as an RValue struct.  If this is an
49/// aggregate expression, the aggloc/agglocvolatile arguments indicate where the
50/// result should be returned.
51RValue CodeGenFunction::EmitAnyExpr(const Expr *E, llvm::Value *AggLoc,
52                                    bool IsAggLocVolatile, bool IgnoreResult,
53                                    bool IsInitializer) {
54  if (!hasAggregateLLVMType(E->getType()))
55    return RValue::get(EmitScalarExpr(E, IgnoreResult));
56  else if (E->getType()->isAnyComplexType())
57    return RValue::getComplex(EmitComplexExpr(E, false, false,
58                                              IgnoreResult, IgnoreResult));
59
60  EmitAggExpr(E, AggLoc, IsAggLocVolatile, IgnoreResult, IsInitializer);
61  return RValue::getAggregate(AggLoc, IsAggLocVolatile);
62}
63
64/// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will
65/// always be accessible even if no aggregate location is provided.
66RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E,
67                                          bool IsAggLocVolatile,
68                                          bool IsInitializer) {
69  llvm::Value *AggLoc = 0;
70
71  if (hasAggregateLLVMType(E->getType()) &&
72      !E->getType()->isAnyComplexType())
73    AggLoc = CreateTempAlloca(ConvertType(E->getType()), "agg.tmp");
74  return EmitAnyExpr(E, AggLoc, IsAggLocVolatile, /*IgnoreResult=*/false,
75                     IsInitializer);
76}
77
78RValue CodeGenFunction::EmitReferenceBindingToExpr(const Expr* E,
79                                                   QualType DestType,
80                                                   bool IsInitializer) {
81  bool ShouldDestroyTemporaries = false;
82  unsigned OldNumLiveTemporaries = 0;
83
84  if (const CXXExprWithTemporaries *TE = dyn_cast<CXXExprWithTemporaries>(E)) {
85    ShouldDestroyTemporaries = TE->shouldDestroyTemporaries();
86
87    // Keep track of the current cleanup stack depth.
88    if (ShouldDestroyTemporaries)
89      OldNumLiveTemporaries = LiveTemporaries.size();
90
91    E = TE->getSubExpr();
92  }
93
94  RValue Val;
95  if (E->isLvalue(getContext()) == Expr::LV_Valid) {
96    // Emit the expr as an lvalue.
97    LValue LV = EmitLValue(E);
98    if (LV.isSimple())
99      return RValue::get(LV.getAddress());
100    Val = EmitLoadOfLValue(LV, E->getType());
101
102    if (ShouldDestroyTemporaries) {
103      // Pop temporaries.
104      while (LiveTemporaries.size() > OldNumLiveTemporaries)
105        PopCXXTemporary();
106    }
107  } else {
108    const CXXRecordDecl *BaseClassDecl = 0;
109    const CXXRecordDecl *DerivedClassDecl = 0;
110
111    if (const CastExpr *CE =
112          dyn_cast<CastExpr>(E->IgnoreParenNoopCasts(getContext()))) {
113      if (CE->getCastKind() == CastExpr::CK_DerivedToBase) {
114        E = CE->getSubExpr();
115
116        BaseClassDecl =
117          cast<CXXRecordDecl>(CE->getType()->getAs<RecordType>()->getDecl());
118        DerivedClassDecl =
119          cast<CXXRecordDecl>(E->getType()->getAs<RecordType>()->getDecl());
120      }
121    }
122
123    Val = EmitAnyExprToTemp(E, /*IsAggLocVolatile=*/false,
124                            IsInitializer);
125
126    if (ShouldDestroyTemporaries) {
127      // Pop temporaries.
128      while (LiveTemporaries.size() > OldNumLiveTemporaries)
129        PopCXXTemporary();
130    }
131
132    if (IsInitializer) {
133      // We might have to destroy the temporary variable.
134      if (const RecordType *RT = E->getType()->getAs<RecordType>()) {
135        if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
136          if (!ClassDecl->hasTrivialDestructor()) {
137            const CXXDestructorDecl *Dtor =
138              ClassDecl->getDestructor(getContext());
139
140            CleanupScope scope(*this);
141            EmitCXXDestructorCall(Dtor, Dtor_Complete, Val.getAggregateAddr());
142          }
143        }
144      }
145    }
146
147    // Check if need to perform the derived-to-base cast.
148    if (BaseClassDecl) {
149      llvm::Value *Derived = Val.getAggregateAddr();
150      llvm::Value *Base =
151        GetAddressCXXOfBaseClass(Derived, DerivedClassDecl, BaseClassDecl,
152                                 /*NullCheckValue=*/false);
153      return RValue::get(Base);
154    }
155  }
156
157  if (Val.isAggregate()) {
158    Val = RValue::get(Val.getAggregateAddr());
159  } else {
160    // Create a temporary variable that we can bind the reference to.
161    llvm::Value *Temp = CreateTempAlloca(ConvertTypeForMem(E->getType()),
162                                         "reftmp");
163    if (Val.isScalar())
164      EmitStoreOfScalar(Val.getScalarVal(), Temp, false, E->getType());
165    else
166      StoreComplexToAddr(Val.getComplexVal(), Temp, false);
167    Val = RValue::get(Temp);
168  }
169
170  return Val;
171}
172
173
174/// getAccessedFieldNo - Given an encoded value and a result number, return the
175/// input field number being accessed.
176unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
177                                             const llvm::Constant *Elts) {
178  if (isa<llvm::ConstantAggregateZero>(Elts))
179    return 0;
180
181  return cast<llvm::ConstantInt>(Elts->getOperand(Idx))->getZExtValue();
182}
183
184
185//===----------------------------------------------------------------------===//
186//                         LValue Expression Emission
187//===----------------------------------------------------------------------===//
188
189RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
190  if (Ty->isVoidType())
191    return RValue::get(0);
192
193  if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
194    const llvm::Type *EltTy = ConvertType(CTy->getElementType());
195    llvm::Value *U = llvm::UndefValue::get(EltTy);
196    return RValue::getComplex(std::make_pair(U, U));
197  }
198
199  if (hasAggregateLLVMType(Ty)) {
200    const llvm::Type *LTy = llvm::PointerType::getUnqual(ConvertType(Ty));
201    return RValue::getAggregate(llvm::UndefValue::get(LTy));
202  }
203
204  return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
205}
206
207RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
208                                              const char *Name) {
209  ErrorUnsupported(E, Name);
210  return GetUndefRValue(E->getType());
211}
212
213LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
214                                              const char *Name) {
215  ErrorUnsupported(E, Name);
216  llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
217  return LValue::MakeAddr(llvm::UndefValue::get(Ty),
218                          MakeQualifiers(E->getType()));
219}
220
221/// EmitLValue - Emit code to compute a designator that specifies the location
222/// of the expression.
223///
224/// This can return one of two things: a simple address or a bitfield reference.
225/// In either case, the LLVM Value* in the LValue structure is guaranteed to be
226/// an LLVM pointer type.
227///
228/// If this returns a bitfield reference, nothing about the pointee type of the
229/// LLVM value is known: For example, it may not be a pointer to an integer.
230///
231/// If this returns a normal address, and if the lvalue's C type is fixed size,
232/// this method guarantees that the returned pointer type will point to an LLVM
233/// type of the same size of the lvalue's type.  If the lvalue has a variable
234/// length type, this is not possible.
235///
236LValue CodeGenFunction::EmitLValue(const Expr *E) {
237  switch (E->getStmtClass()) {
238  default: return EmitUnsupportedLValue(E, "l-value expression");
239
240  case Expr::BinaryOperatorClass:
241    return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
242  case Expr::CallExprClass:
243  case Expr::CXXMemberCallExprClass:
244  case Expr::CXXOperatorCallExprClass:
245    return EmitCallExprLValue(cast<CallExpr>(E));
246  case Expr::VAArgExprClass:
247    return EmitVAArgExprLValue(cast<VAArgExpr>(E));
248  case Expr::DeclRefExprClass:
249    return EmitDeclRefLValue(cast<DeclRefExpr>(E));
250  case Expr::ParenExprClass:return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
251  case Expr::PredefinedExprClass:
252    return EmitPredefinedLValue(cast<PredefinedExpr>(E));
253  case Expr::StringLiteralClass:
254    return EmitStringLiteralLValue(cast<StringLiteral>(E));
255  case Expr::ObjCEncodeExprClass:
256    return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
257
258  case Expr::BlockDeclRefExprClass:
259    return EmitBlockDeclRefLValue(cast<BlockDeclRefExpr>(E));
260
261  case Expr::CXXConditionDeclExprClass:
262    return EmitCXXConditionDeclLValue(cast<CXXConditionDeclExpr>(E));
263  case Expr::CXXTemporaryObjectExprClass:
264  case Expr::CXXConstructExprClass:
265    return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
266  case Expr::CXXBindTemporaryExprClass:
267    return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
268  case Expr::CXXExprWithTemporariesClass:
269    return EmitCXXExprWithTemporariesLValue(cast<CXXExprWithTemporaries>(E));
270
271  case Expr::ObjCMessageExprClass:
272    return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
273  case Expr::ObjCIvarRefExprClass:
274    return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
275  case Expr::ObjCPropertyRefExprClass:
276    return EmitObjCPropertyRefLValue(cast<ObjCPropertyRefExpr>(E));
277  case Expr::ObjCImplicitSetterGetterRefExprClass:
278    return EmitObjCKVCRefLValue(cast<ObjCImplicitSetterGetterRefExpr>(E));
279  case Expr::ObjCSuperExprClass:
280    return EmitObjCSuperExprLValue(cast<ObjCSuperExpr>(E));
281
282  case Expr::StmtExprClass:
283    return EmitStmtExprLValue(cast<StmtExpr>(E));
284  case Expr::UnaryOperatorClass:
285    return EmitUnaryOpLValue(cast<UnaryOperator>(E));
286  case Expr::ArraySubscriptExprClass:
287    return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
288  case Expr::ExtVectorElementExprClass:
289    return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
290  case Expr::MemberExprClass:
291    return EmitMemberExpr(cast<MemberExpr>(E));
292  case Expr::CompoundLiteralExprClass:
293    return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
294  case Expr::ConditionalOperatorClass:
295    return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
296  case Expr::ChooseExprClass:
297    return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(getContext()));
298  case Expr::ImplicitCastExprClass:
299  case Expr::CStyleCastExprClass:
300  case Expr::CXXFunctionalCastExprClass:
301  case Expr::CXXStaticCastExprClass:
302  case Expr::CXXDynamicCastExprClass:
303  case Expr::CXXReinterpretCastExprClass:
304  case Expr::CXXConstCastExprClass:
305    return EmitCastLValue(cast<CastExpr>(E));
306  case Expr::CXXZeroInitValueExprClass:
307    return EmitNullInitializationLValue(cast<CXXZeroInitValueExpr>(E));
308  }
309}
310
311llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile,
312                                               QualType Ty) {
313  llvm::Value *V = Builder.CreateLoad(Addr, Volatile, "tmp");
314
315  // Bool can have different representation in memory than in registers.
316  if (Ty->isBooleanType())
317    if (V->getType() != llvm::Type::getInt1Ty(VMContext))
318      V = Builder.CreateTrunc(V, llvm::Type::getInt1Ty(VMContext), "tobool");
319
320  return V;
321}
322
323void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr,
324                                        bool Volatile, QualType Ty) {
325
326  if (Ty->isBooleanType()) {
327    // Bool can have different representation in memory than in registers.
328    const llvm::Type *SrcTy = Value->getType();
329    const llvm::PointerType *DstPtr = cast<llvm::PointerType>(Addr->getType());
330    if (DstPtr->getElementType() != SrcTy) {
331      const llvm::Type *MemTy =
332        llvm::PointerType::get(SrcTy, DstPtr->getAddressSpace());
333      Addr = Builder.CreateBitCast(Addr, MemTy, "storetmp");
334    }
335  }
336  Builder.CreateStore(Value, Addr, Volatile);
337}
338
339/// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
340/// method emits the address of the lvalue, then loads the result as an rvalue,
341/// returning the rvalue.
342RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, QualType ExprType) {
343  if (LV.isObjCWeak()) {
344    // load of a __weak object.
345    llvm::Value *AddrWeakObj = LV.getAddress();
346    return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
347                                                             AddrWeakObj));
348  }
349
350  if (LV.isSimple()) {
351    llvm::Value *Ptr = LV.getAddress();
352    const llvm::Type *EltTy =
353      cast<llvm::PointerType>(Ptr->getType())->getElementType();
354
355    // Simple scalar l-value.
356    if (EltTy->isSingleValueType())
357      return RValue::get(EmitLoadOfScalar(Ptr, LV.isVolatileQualified(),
358                                          ExprType));
359
360    assert(ExprType->isFunctionType() && "Unknown scalar value");
361    return RValue::get(Ptr);
362  }
363
364  if (LV.isVectorElt()) {
365    llvm::Value *Vec = Builder.CreateLoad(LV.getVectorAddr(),
366                                          LV.isVolatileQualified(), "tmp");
367    return RValue::get(Builder.CreateExtractElement(Vec, LV.getVectorIdx(),
368                                                    "vecext"));
369  }
370
371  // If this is a reference to a subset of the elements of a vector, either
372  // shuffle the input or extract/insert them as appropriate.
373  if (LV.isExtVectorElt())
374    return EmitLoadOfExtVectorElementLValue(LV, ExprType);
375
376  if (LV.isBitfield())
377    return EmitLoadOfBitfieldLValue(LV, ExprType);
378
379  if (LV.isPropertyRef())
380    return EmitLoadOfPropertyRefLValue(LV, ExprType);
381
382  assert(LV.isKVCRef() && "Unknown LValue type!");
383  return EmitLoadOfKVCRefLValue(LV, ExprType);
384}
385
386RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
387                                                 QualType ExprType) {
388  unsigned StartBit = LV.getBitfieldStartBit();
389  unsigned BitfieldSize = LV.getBitfieldSize();
390  llvm::Value *Ptr = LV.getBitfieldAddr();
391
392  const llvm::Type *EltTy =
393    cast<llvm::PointerType>(Ptr->getType())->getElementType();
394  unsigned EltTySize = CGM.getTargetData().getTypeSizeInBits(EltTy);
395
396  // In some cases the bitfield may straddle two memory locations.  Currently we
397  // load the entire bitfield, then do the magic to sign-extend it if
398  // necessary. This results in somewhat more code than necessary for the common
399  // case (one load), since two shifts accomplish both the masking and sign
400  // extension.
401  unsigned LowBits = std::min(BitfieldSize, EltTySize - StartBit);
402  llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "tmp");
403
404  // Shift to proper location.
405  if (StartBit)
406    Val = Builder.CreateLShr(Val, llvm::ConstantInt::get(EltTy, StartBit),
407                             "bf.lo");
408
409  // Mask off unused bits.
410  llvm::Constant *LowMask = llvm::ConstantInt::get(VMContext,
411                                llvm::APInt::getLowBitsSet(EltTySize, LowBits));
412  Val = Builder.CreateAnd(Val, LowMask, "bf.lo.cleared");
413
414  // Fetch the high bits if necessary.
415  if (LowBits < BitfieldSize) {
416    unsigned HighBits = BitfieldSize - LowBits;
417    llvm::Value *HighPtr = Builder.CreateGEP(Ptr, llvm::ConstantInt::get(
418                            llvm::Type::getInt32Ty(VMContext), 1), "bf.ptr.hi");
419    llvm::Value *HighVal = Builder.CreateLoad(HighPtr,
420                                              LV.isVolatileQualified(),
421                                              "tmp");
422
423    // Mask off unused bits.
424    llvm::Constant *HighMask = llvm::ConstantInt::get(VMContext,
425                               llvm::APInt::getLowBitsSet(EltTySize, HighBits));
426    HighVal = Builder.CreateAnd(HighVal, HighMask, "bf.lo.cleared");
427
428    // Shift to proper location and or in to bitfield value.
429    HighVal = Builder.CreateShl(HighVal,
430                                llvm::ConstantInt::get(EltTy, LowBits));
431    Val = Builder.CreateOr(Val, HighVal, "bf.val");
432  }
433
434  // Sign extend if necessary.
435  if (LV.isBitfieldSigned()) {
436    llvm::Value *ExtraBits = llvm::ConstantInt::get(EltTy,
437                                                    EltTySize - BitfieldSize);
438    Val = Builder.CreateAShr(Builder.CreateShl(Val, ExtraBits),
439                             ExtraBits, "bf.val.sext");
440  }
441
442  // The bitfield type and the normal type differ when the storage sizes differ
443  // (currently just _Bool).
444  Val = Builder.CreateIntCast(Val, ConvertType(ExprType), false, "tmp");
445
446  return RValue::get(Val);
447}
448
449RValue CodeGenFunction::EmitLoadOfPropertyRefLValue(LValue LV,
450                                                    QualType ExprType) {
451  return EmitObjCPropertyGet(LV.getPropertyRefExpr());
452}
453
454RValue CodeGenFunction::EmitLoadOfKVCRefLValue(LValue LV,
455                                               QualType ExprType) {
456  return EmitObjCPropertyGet(LV.getKVCRefExpr());
457}
458
459// If this is a reference to a subset of the elements of a vector, create an
460// appropriate shufflevector.
461RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV,
462                                                         QualType ExprType) {
463  llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddr(),
464                                        LV.isVolatileQualified(), "tmp");
465
466  const llvm::Constant *Elts = LV.getExtVectorElts();
467
468  // If the result of the expression is a non-vector type, we must be extracting
469  // a single element.  Just codegen as an extractelement.
470  const VectorType *ExprVT = ExprType->getAs<VectorType>();
471  if (!ExprVT) {
472    unsigned InIdx = getAccessedFieldNo(0, Elts);
473    llvm::Value *Elt = llvm::ConstantInt::get(
474                                      llvm::Type::getInt32Ty(VMContext), InIdx);
475    return RValue::get(Builder.CreateExtractElement(Vec, Elt, "tmp"));
476  }
477
478  // Always use shuffle vector to try to retain the original program structure
479  unsigned NumResultElts = ExprVT->getNumElements();
480
481  llvm::SmallVector<llvm::Constant*, 4> Mask;
482  for (unsigned i = 0; i != NumResultElts; ++i) {
483    unsigned InIdx = getAccessedFieldNo(i, Elts);
484    Mask.push_back(llvm::ConstantInt::get(
485                                     llvm::Type::getInt32Ty(VMContext), InIdx));
486  }
487
488  llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
489  Vec = Builder.CreateShuffleVector(Vec,
490                                    llvm::UndefValue::get(Vec->getType()),
491                                    MaskV, "tmp");
492  return RValue::get(Vec);
493}
494
495
496
497/// EmitStoreThroughLValue - Store the specified rvalue into the specified
498/// lvalue, where both are guaranteed to the have the same type, and that type
499/// is 'Ty'.
500void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
501                                             QualType Ty) {
502  if (!Dst.isSimple()) {
503    if (Dst.isVectorElt()) {
504      // Read/modify/write the vector, inserting the new element.
505      llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddr(),
506                                            Dst.isVolatileQualified(), "tmp");
507      Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
508                                        Dst.getVectorIdx(), "vecins");
509      Builder.CreateStore(Vec, Dst.getVectorAddr(),Dst.isVolatileQualified());
510      return;
511    }
512
513    // If this is an update of extended vector elements, insert them as
514    // appropriate.
515    if (Dst.isExtVectorElt())
516      return EmitStoreThroughExtVectorComponentLValue(Src, Dst, Ty);
517
518    if (Dst.isBitfield())
519      return EmitStoreThroughBitfieldLValue(Src, Dst, Ty);
520
521    if (Dst.isPropertyRef())
522      return EmitStoreThroughPropertyRefLValue(Src, Dst, Ty);
523
524    assert(Dst.isKVCRef() && "Unknown LValue type");
525    return EmitStoreThroughKVCRefLValue(Src, Dst, Ty);
526  }
527
528  if (Dst.isObjCWeak() && !Dst.isNonGC()) {
529    // load of a __weak object.
530    llvm::Value *LvalueDst = Dst.getAddress();
531    llvm::Value *src = Src.getScalarVal();
532     CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
533    return;
534  }
535
536  if (Dst.isObjCStrong() && !Dst.isNonGC()) {
537    // load of a __strong object.
538    llvm::Value *LvalueDst = Dst.getAddress();
539    llvm::Value *src = Src.getScalarVal();
540    if (Dst.isObjCIvar()) {
541      assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
542      const llvm::Type *ResultType = ConvertType(getContext().LongTy);
543      llvm::Value *RHS = EmitScalarExpr(Dst.getBaseIvarExp());
544      llvm::Value *dst = RHS;
545      RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
546      llvm::Value *LHS =
547        Builder.CreatePtrToInt(LvalueDst, ResultType, "sub.ptr.lhs.cast");
548      llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
549      CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
550                                              BytesBetween);
551    } else if (Dst.isGlobalObjCRef())
552      CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst);
553    else
554      CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
555    return;
556  }
557
558  assert(Src.isScalar() && "Can't emit an agg store with this method");
559  EmitStoreOfScalar(Src.getScalarVal(), Dst.getAddress(),
560                    Dst.isVolatileQualified(), Ty);
561}
562
563void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
564                                                     QualType Ty,
565                                                     llvm::Value **Result) {
566  unsigned StartBit = Dst.getBitfieldStartBit();
567  unsigned BitfieldSize = Dst.getBitfieldSize();
568  llvm::Value *Ptr = Dst.getBitfieldAddr();
569
570  const llvm::Type *EltTy =
571    cast<llvm::PointerType>(Ptr->getType())->getElementType();
572  unsigned EltTySize = CGM.getTargetData().getTypeSizeInBits(EltTy);
573
574  // Get the new value, cast to the appropriate type and masked to exactly the
575  // size of the bit-field.
576  llvm::Value *SrcVal = Src.getScalarVal();
577  llvm::Value *NewVal = Builder.CreateIntCast(SrcVal, EltTy, false, "tmp");
578  llvm::Constant *Mask = llvm::ConstantInt::get(VMContext,
579                           llvm::APInt::getLowBitsSet(EltTySize, BitfieldSize));
580  NewVal = Builder.CreateAnd(NewVal, Mask, "bf.value");
581
582  // Return the new value of the bit-field, if requested.
583  if (Result) {
584    // Cast back to the proper type for result.
585    const llvm::Type *SrcTy = SrcVal->getType();
586    llvm::Value *SrcTrunc = Builder.CreateIntCast(NewVal, SrcTy, false,
587                                                  "bf.reload.val");
588
589    // Sign extend if necessary.
590    if (Dst.isBitfieldSigned()) {
591      unsigned SrcTySize = CGM.getTargetData().getTypeSizeInBits(SrcTy);
592      llvm::Value *ExtraBits = llvm::ConstantInt::get(SrcTy,
593                                                      SrcTySize - BitfieldSize);
594      SrcTrunc = Builder.CreateAShr(Builder.CreateShl(SrcTrunc, ExtraBits),
595                                    ExtraBits, "bf.reload.sext");
596    }
597
598    *Result = SrcTrunc;
599  }
600
601  // In some cases the bitfield may straddle two memory locations.  Emit the low
602  // part first and check to see if the high needs to be done.
603  unsigned LowBits = std::min(BitfieldSize, EltTySize - StartBit);
604  llvm::Value *LowVal = Builder.CreateLoad(Ptr, Dst.isVolatileQualified(),
605                                           "bf.prev.low");
606
607  // Compute the mask for zero-ing the low part of this bitfield.
608  llvm::Constant *InvMask =
609    llvm::ConstantInt::get(VMContext,
610             ~llvm::APInt::getBitsSet(EltTySize, StartBit, StartBit + LowBits));
611
612  // Compute the new low part as
613  //   LowVal = (LowVal & InvMask) | (NewVal << StartBit),
614  // with the shift of NewVal implicitly stripping the high bits.
615  llvm::Value *NewLowVal =
616    Builder.CreateShl(NewVal, llvm::ConstantInt::get(EltTy, StartBit),
617                      "bf.value.lo");
618  LowVal = Builder.CreateAnd(LowVal, InvMask, "bf.prev.lo.cleared");
619  LowVal = Builder.CreateOr(LowVal, NewLowVal, "bf.new.lo");
620
621  // Write back.
622  Builder.CreateStore(LowVal, Ptr, Dst.isVolatileQualified());
623
624  // If the low part doesn't cover the bitfield emit a high part.
625  if (LowBits < BitfieldSize) {
626    unsigned HighBits = BitfieldSize - LowBits;
627    llvm::Value *HighPtr =  Builder.CreateGEP(Ptr, llvm::ConstantInt::get(
628                            llvm::Type::getInt32Ty(VMContext), 1), "bf.ptr.hi");
629    llvm::Value *HighVal = Builder.CreateLoad(HighPtr,
630                                              Dst.isVolatileQualified(),
631                                              "bf.prev.hi");
632
633    // Compute the mask for zero-ing the high part of this bitfield.
634    llvm::Constant *InvMask =
635      llvm::ConstantInt::get(VMContext, ~llvm::APInt::getLowBitsSet(EltTySize,
636                               HighBits));
637
638    // Compute the new high part as
639    //   HighVal = (HighVal & InvMask) | (NewVal lshr LowBits),
640    // where the high bits of NewVal have already been cleared and the
641    // shift stripping the low bits.
642    llvm::Value *NewHighVal =
643      Builder.CreateLShr(NewVal, llvm::ConstantInt::get(EltTy, LowBits),
644                        "bf.value.high");
645    HighVal = Builder.CreateAnd(HighVal, InvMask, "bf.prev.hi.cleared");
646    HighVal = Builder.CreateOr(HighVal, NewHighVal, "bf.new.hi");
647
648    // Write back.
649    Builder.CreateStore(HighVal, HighPtr, Dst.isVolatileQualified());
650  }
651}
652
653void CodeGenFunction::EmitStoreThroughPropertyRefLValue(RValue Src,
654                                                        LValue Dst,
655                                                        QualType Ty) {
656  EmitObjCPropertySet(Dst.getPropertyRefExpr(), Src);
657}
658
659void CodeGenFunction::EmitStoreThroughKVCRefLValue(RValue Src,
660                                                   LValue Dst,
661                                                   QualType Ty) {
662  EmitObjCPropertySet(Dst.getKVCRefExpr(), Src);
663}
664
665void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
666                                                               LValue Dst,
667                                                               QualType Ty) {
668  // This access turns into a read/modify/write of the vector.  Load the input
669  // value now.
670  llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddr(),
671                                        Dst.isVolatileQualified(), "tmp");
672  const llvm::Constant *Elts = Dst.getExtVectorElts();
673
674  llvm::Value *SrcVal = Src.getScalarVal();
675
676  if (const VectorType *VTy = Ty->getAs<VectorType>()) {
677    unsigned NumSrcElts = VTy->getNumElements();
678    unsigned NumDstElts =
679       cast<llvm::VectorType>(Vec->getType())->getNumElements();
680    if (NumDstElts == NumSrcElts) {
681      // Use shuffle vector is the src and destination are the same number of
682      // elements and restore the vector mask since it is on the side it will be
683      // stored.
684      llvm::SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
685      for (unsigned i = 0; i != NumSrcElts; ++i) {
686        unsigned InIdx = getAccessedFieldNo(i, Elts);
687        Mask[InIdx] = llvm::ConstantInt::get(
688                                          llvm::Type::getInt32Ty(VMContext), i);
689      }
690
691      llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
692      Vec = Builder.CreateShuffleVector(SrcVal,
693                                        llvm::UndefValue::get(Vec->getType()),
694                                        MaskV, "tmp");
695    } else if (NumDstElts > NumSrcElts) {
696      // Extended the source vector to the same length and then shuffle it
697      // into the destination.
698      // FIXME: since we're shuffling with undef, can we just use the indices
699      //        into that?  This could be simpler.
700      llvm::SmallVector<llvm::Constant*, 4> ExtMask;
701      const llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext);
702      unsigned i;
703      for (i = 0; i != NumSrcElts; ++i)
704        ExtMask.push_back(llvm::ConstantInt::get(Int32Ty, i));
705      for (; i != NumDstElts; ++i)
706        ExtMask.push_back(llvm::UndefValue::get(Int32Ty));
707      llvm::Value *ExtMaskV = llvm::ConstantVector::get(&ExtMask[0],
708                                                        ExtMask.size());
709      llvm::Value *ExtSrcVal =
710        Builder.CreateShuffleVector(SrcVal,
711                                    llvm::UndefValue::get(SrcVal->getType()),
712                                    ExtMaskV, "tmp");
713      // build identity
714      llvm::SmallVector<llvm::Constant*, 4> Mask;
715      for (unsigned i = 0; i != NumDstElts; ++i)
716        Mask.push_back(llvm::ConstantInt::get(Int32Ty, i));
717
718      // modify when what gets shuffled in
719      for (unsigned i = 0; i != NumSrcElts; ++i) {
720        unsigned Idx = getAccessedFieldNo(i, Elts);
721        Mask[Idx] = llvm::ConstantInt::get(Int32Ty, i+NumDstElts);
722      }
723      llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
724      Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV, "tmp");
725    } else {
726      // We should never shorten the vector
727      assert(0 && "unexpected shorten vector length");
728    }
729  } else {
730    // If the Src is a scalar (not a vector) it must be updating one element.
731    unsigned InIdx = getAccessedFieldNo(0, Elts);
732    const llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext);
733    llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx);
734    Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt, "tmp");
735  }
736
737  Builder.CreateStore(Vec, Dst.getExtVectorAddr(), Dst.isVolatileQualified());
738}
739
740// setObjCGCLValueClass - sets class of he lvalue for the purpose of
741// generating write-barries API. It is currently a global, ivar,
742// or neither.
743static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
744                                 LValue &LV) {
745  if (Ctx.getLangOptions().getGCMode() == LangOptions::NonGC)
746    return;
747
748  if (isa<ObjCIvarRefExpr>(E)) {
749    LV.SetObjCIvar(LV, true);
750    ObjCIvarRefExpr *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr*>(E));
751    LV.setBaseIvarExp(Exp->getBase());
752    LV.SetObjCArray(LV, E->getType()->isArrayType());
753    return;
754  }
755
756  if (const DeclRefExpr *Exp = dyn_cast<DeclRefExpr>(E)) {
757    if (const VarDecl *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
758      if ((VD->isBlockVarDecl() && !VD->hasLocalStorage()) ||
759          VD->isFileVarDecl())
760        LV.SetGlobalObjCRef(LV, true);
761    }
762    LV.SetObjCArray(LV, E->getType()->isArrayType());
763    return;
764  }
765
766  if (const UnaryOperator *Exp = dyn_cast<UnaryOperator>(E)) {
767    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
768    return;
769  }
770
771  if (const ParenExpr *Exp = dyn_cast<ParenExpr>(E)) {
772    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
773    if (LV.isObjCIvar()) {
774      // If cast is to a structure pointer, follow gcc's behavior and make it
775      // a non-ivar write-barrier.
776      QualType ExpTy = E->getType();
777      if (ExpTy->isPointerType())
778        ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
779      if (ExpTy->isRecordType())
780        LV.SetObjCIvar(LV, false);
781    }
782    return;
783  }
784  if (const ImplicitCastExpr *Exp = dyn_cast<ImplicitCastExpr>(E)) {
785    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
786    return;
787  }
788
789  if (const CStyleCastExpr *Exp = dyn_cast<CStyleCastExpr>(E)) {
790    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
791    return;
792  }
793
794  if (const ArraySubscriptExpr *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
795    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
796    if (LV.isObjCIvar() && !LV.isObjCArray())
797      // Using array syntax to assigning to what an ivar points to is not
798      // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
799      LV.SetObjCIvar(LV, false);
800    else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
801      // Using array syntax to assigning to what global points to is not
802      // same as assigning to the global itself. {id *G;} G[i] = 0;
803      LV.SetGlobalObjCRef(LV, false);
804    return;
805  }
806
807  if (const MemberExpr *Exp = dyn_cast<MemberExpr>(E)) {
808    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
809    // We don't know if member is an 'ivar', but this flag is looked at
810    // only in the context of LV.isObjCIvar().
811    LV.SetObjCArray(LV, E->getType()->isArrayType());
812    return;
813  }
814}
815
816static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
817                                      const Expr *E, const VarDecl *VD) {
818  assert(VD->hasExternalStorage() || VD->isFileVarDecl() &&
819         "Var decl must have external storage or be a file var decl!");
820
821  llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
822  if (VD->getType()->isReferenceType())
823    V = CGF.Builder.CreateLoad(V, "tmp");
824  LValue LV = LValue::MakeAddr(V, CGF.MakeQualifiers(E->getType()));
825  setObjCGCLValueClass(CGF.getContext(), E, LV);
826  return LV;
827}
828
829LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
830  const NamedDecl *ND = E->getDecl();
831
832  if (const VarDecl *VD = dyn_cast<VarDecl>(ND)) {
833
834    // Check if this is a global variable.
835    if (VD->hasExternalStorage() || VD->isFileVarDecl())
836      return EmitGlobalVarDeclLValue(*this, E, VD);
837
838    bool NonGCable = VD->hasLocalStorage() && !VD->hasAttr<BlocksAttr>();
839
840    llvm::Value *V = LocalDeclMap[VD];
841    assert(V && "DeclRefExpr not entered in LocalDeclMap?");
842
843    Qualifiers Quals = MakeQualifiers(E->getType());
844    // local variables do not get their gc attribute set.
845    // local static?
846    if (NonGCable) Quals.removeObjCGCAttr();
847
848    if (VD->hasAttr<BlocksAttr>()) {
849      V = Builder.CreateStructGEP(V, 1, "forwarding");
850      V = Builder.CreateLoad(V, false);
851      V = Builder.CreateStructGEP(V, getByRefValueLLVMField(VD),
852                                  VD->getNameAsString());
853    }
854    if (VD->getType()->isReferenceType())
855      V = Builder.CreateLoad(V, "tmp");
856    LValue LV = LValue::MakeAddr(V, Quals);
857    LValue::SetObjCNonGC(LV, NonGCable);
858    setObjCGCLValueClass(getContext(), E, LV);
859    return LV;
860  }
861
862  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) {
863    llvm::Value* V = CGM.GetAddrOfFunction(FD);
864    if (!FD->hasPrototype()) {
865      if (const FunctionProtoType *Proto =
866              FD->getType()->getAs<FunctionProtoType>()) {
867        // Ugly case: for a K&R-style definition, the type of the definition
868        // isn't the same as the type of a use.  Correct for this with a
869        // bitcast.
870        QualType NoProtoType =
871            getContext().getFunctionNoProtoType(Proto->getResultType());
872        NoProtoType = getContext().getPointerType(NoProtoType);
873        V = Builder.CreateBitCast(V, ConvertType(NoProtoType), "tmp");
874      }
875    }
876    return LValue::MakeAddr(V, MakeQualifiers(E->getType()));
877  }
878
879  if (E->getQualifier()) {
880    // FIXME: the qualifier check does not seem sufficient here
881    return EmitPointerToDataMemberLValue(cast<FieldDecl>(ND));
882  }
883
884  assert(false && "Unhandled DeclRefExpr");
885
886  // an invalid LValue, but the assert will
887  // ensure that this point is never reached.
888  return LValue();
889}
890
891LValue CodeGenFunction::EmitBlockDeclRefLValue(const BlockDeclRefExpr *E) {
892  return LValue::MakeAddr(GetAddrOfBlockDecl(E), MakeQualifiers(E->getType()));
893}
894
895LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
896  // __extension__ doesn't affect lvalue-ness.
897  if (E->getOpcode() == UnaryOperator::Extension)
898    return EmitLValue(E->getSubExpr());
899
900  QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
901  switch (E->getOpcode()) {
902  default: assert(0 && "Unknown unary operator lvalue!");
903  case UnaryOperator::Deref: {
904    QualType T = E->getSubExpr()->getType()->getPointeeType();
905    assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
906
907    Qualifiers Quals = MakeQualifiers(T);
908    Quals.setAddressSpace(ExprTy.getAddressSpace());
909
910    LValue LV = LValue::MakeAddr(EmitScalarExpr(E->getSubExpr()), Quals);
911    // We should not generate __weak write barrier on indirect reference
912    // of a pointer to object; as in void foo (__weak id *param); *param = 0;
913    // But, we continue to generate __strong write barrier on indirect write
914    // into a pointer to object.
915    if (getContext().getLangOptions().ObjC1 &&
916        getContext().getLangOptions().getGCMode() != LangOptions::NonGC &&
917        LV.isObjCWeak())
918      LValue::SetObjCNonGC(LV, !E->isOBJCGCCandidate(getContext()));
919    return LV;
920  }
921  case UnaryOperator::Real:
922  case UnaryOperator::Imag:
923    LValue LV = EmitLValue(E->getSubExpr());
924    unsigned Idx = E->getOpcode() == UnaryOperator::Imag;
925    return LValue::MakeAddr(Builder.CreateStructGEP(LV.getAddress(),
926                                                    Idx, "idx"),
927                            MakeQualifiers(ExprTy));
928  }
929}
930
931LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
932  return LValue::MakeAddr(CGM.GetAddrOfConstantStringFromLiteral(E),
933                          Qualifiers());
934}
935
936LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
937  return LValue::MakeAddr(CGM.GetAddrOfConstantStringFromObjCEncode(E),
938                          Qualifiers());
939}
940
941
942LValue CodeGenFunction::EmitPredefinedFunctionName(unsigned Type) {
943  std::string GlobalVarName;
944
945  switch (Type) {
946  default: assert(0 && "Invalid type");
947  case PredefinedExpr::Func:
948    GlobalVarName = "__func__.";
949    break;
950  case PredefinedExpr::Function:
951    GlobalVarName = "__FUNCTION__.";
952    break;
953  case PredefinedExpr::PrettyFunction:
954    GlobalVarName = "__PRETTY_FUNCTION__.";
955    break;
956  }
957
958  llvm::StringRef FnName = CurFn->getName();
959  if (FnName.startswith("\01"))
960    FnName = FnName.substr(1);
961  GlobalVarName += FnName;
962
963  std::string FunctionName =
964    PredefinedExpr::ComputeName(getContext(), (PredefinedExpr::IdentType)Type,
965                                CurCodeDecl);
966
967  llvm::Constant *C =
968    CGM.GetAddrOfConstantCString(FunctionName, GlobalVarName.c_str());
969  return LValue::MakeAddr(C, Qualifiers());
970}
971
972LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
973  switch (E->getIdentType()) {
974  default:
975    return EmitUnsupportedLValue(E, "predefined expression");
976  case PredefinedExpr::Func:
977  case PredefinedExpr::Function:
978  case PredefinedExpr::PrettyFunction:
979    return EmitPredefinedFunctionName(E->getIdentType());
980  }
981}
982
983LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E) {
984  // The index must always be an integer, which is not an aggregate.  Emit it.
985  llvm::Value *Idx = EmitScalarExpr(E->getIdx());
986  QualType IdxTy  = E->getIdx()->getType();
987  bool IdxSigned = IdxTy->isSignedIntegerType();
988
989  // If the base is a vector type, then we are forming a vector element lvalue
990  // with this subscript.
991  if (E->getBase()->getType()->isVectorType()) {
992    // Emit the vector as an lvalue to get its address.
993    LValue LHS = EmitLValue(E->getBase());
994    assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
995    Idx = Builder.CreateIntCast(Idx,
996                          llvm::Type::getInt32Ty(VMContext), IdxSigned, "vidx");
997    return LValue::MakeVectorElt(LHS.getAddress(), Idx,
998                                 E->getBase()->getType().getCVRQualifiers());
999  }
1000
1001  // The base must be a pointer, which is not an aggregate.  Emit it.
1002  llvm::Value *Base = EmitScalarExpr(E->getBase());
1003
1004  // Extend or truncate the index type to 32 or 64-bits.
1005  unsigned IdxBitwidth = cast<llvm::IntegerType>(Idx->getType())->getBitWidth();
1006  if (IdxBitwidth != LLVMPointerWidth)
1007    Idx = Builder.CreateIntCast(Idx,
1008                            llvm::IntegerType::get(VMContext, LLVMPointerWidth),
1009                                IdxSigned, "idxprom");
1010
1011  // We know that the pointer points to a type of the correct size, unless the
1012  // size is a VLA or Objective-C interface.
1013  llvm::Value *Address = 0;
1014  if (const VariableArrayType *VAT =
1015        getContext().getAsVariableArrayType(E->getType())) {
1016    llvm::Value *VLASize = GetVLASize(VAT);
1017
1018    Idx = Builder.CreateMul(Idx, VLASize);
1019
1020    QualType BaseType = getContext().getBaseElementType(VAT);
1021
1022    uint64_t BaseTypeSize = getContext().getTypeSize(BaseType) / 8;
1023    Idx = Builder.CreateUDiv(Idx,
1024                             llvm::ConstantInt::get(Idx->getType(),
1025                                                    BaseTypeSize));
1026    Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
1027  } else if (const ObjCInterfaceType *OIT =
1028             dyn_cast<ObjCInterfaceType>(E->getType())) {
1029    llvm::Value *InterfaceSize =
1030      llvm::ConstantInt::get(Idx->getType(),
1031                             getContext().getTypeSize(OIT) / 8);
1032
1033    Idx = Builder.CreateMul(Idx, InterfaceSize);
1034
1035    const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext);
1036    Address = Builder.CreateGEP(Builder.CreateBitCast(Base, i8PTy),
1037                                Idx, "arrayidx");
1038    Address = Builder.CreateBitCast(Address, Base->getType());
1039  } else {
1040    Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
1041  }
1042
1043  QualType T = E->getBase()->getType()->getPointeeType();
1044  assert(!T.isNull() &&
1045         "CodeGenFunction::EmitArraySubscriptExpr(): Illegal base type");
1046
1047  Qualifiers Quals = MakeQualifiers(T);
1048  Quals.setAddressSpace(E->getBase()->getType().getAddressSpace());
1049
1050  LValue LV = LValue::MakeAddr(Address, Quals);
1051  if (getContext().getLangOptions().ObjC1 &&
1052      getContext().getLangOptions().getGCMode() != LangOptions::NonGC) {
1053    LValue::SetObjCNonGC(LV, !E->isOBJCGCCandidate(getContext()));
1054    setObjCGCLValueClass(getContext(), E, LV);
1055  }
1056  return LV;
1057}
1058
1059static
1060llvm::Constant *GenerateConstantVector(llvm::LLVMContext &VMContext,
1061                                       llvm::SmallVector<unsigned, 4> &Elts) {
1062  llvm::SmallVector<llvm::Constant *, 4> CElts;
1063
1064  for (unsigned i = 0, e = Elts.size(); i != e; ++i)
1065    CElts.push_back(llvm::ConstantInt::get(
1066                                   llvm::Type::getInt32Ty(VMContext), Elts[i]));
1067
1068  return llvm::ConstantVector::get(&CElts[0], CElts.size());
1069}
1070
1071LValue CodeGenFunction::
1072EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
1073  // Emit the base vector as an l-value.
1074  LValue Base;
1075
1076  // ExtVectorElementExpr's base can either be a vector or pointer to vector.
1077  if (!E->isArrow()) {
1078    assert(E->getBase()->getType()->isVectorType());
1079    Base = EmitLValue(E->getBase());
1080  } else {
1081    const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
1082    llvm::Value *Ptr = EmitScalarExpr(E->getBase());
1083    Qualifiers Quals = MakeQualifiers(PT->getPointeeType());
1084    Quals.removeObjCGCAttr();
1085    Base = LValue::MakeAddr(Ptr, Quals);
1086  }
1087
1088  // Encode the element access list into a vector of unsigned indices.
1089  llvm::SmallVector<unsigned, 4> Indices;
1090  E->getEncodedElementAccess(Indices);
1091
1092  if (Base.isSimple()) {
1093    llvm::Constant *CV = GenerateConstantVector(VMContext, Indices);
1094    return LValue::MakeExtVectorElt(Base.getAddress(), CV,
1095                                    Base.getVRQualifiers());
1096  }
1097  assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
1098
1099  llvm::Constant *BaseElts = Base.getExtVectorElts();
1100  llvm::SmallVector<llvm::Constant *, 4> CElts;
1101
1102  const llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext);
1103  for (unsigned i = 0, e = Indices.size(); i != e; ++i) {
1104    if (isa<llvm::ConstantAggregateZero>(BaseElts))
1105      CElts.push_back(llvm::ConstantInt::get(Int32Ty, 0));
1106    else
1107      CElts.push_back(cast<llvm::Constant>(BaseElts->getOperand(Indices[i])));
1108  }
1109  llvm::Constant *CV = llvm::ConstantVector::get(&CElts[0], CElts.size());
1110  return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV,
1111                                  Base.getVRQualifiers());
1112}
1113
1114LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
1115  bool isUnion = false;
1116  bool isNonGC = false;
1117  Expr *BaseExpr = E->getBase();
1118  llvm::Value *BaseValue = NULL;
1119  Qualifiers BaseQuals;
1120
1121  // If this is s.x, emit s as an lvalue.  If it is s->x, emit s as a scalar.
1122  if (E->isArrow()) {
1123    BaseValue = EmitScalarExpr(BaseExpr);
1124    const PointerType *PTy =
1125      BaseExpr->getType()->getAs<PointerType>();
1126    if (PTy->getPointeeType()->isUnionType())
1127      isUnion = true;
1128    BaseQuals = PTy->getPointeeType().getQualifiers();
1129  } else if (isa<ObjCPropertyRefExpr>(BaseExpr->IgnoreParens()) ||
1130             isa<ObjCImplicitSetterGetterRefExpr>(
1131               BaseExpr->IgnoreParens())) {
1132    RValue RV = EmitObjCPropertyGet(BaseExpr);
1133    BaseValue = RV.getAggregateAddr();
1134    if (BaseExpr->getType()->isUnionType())
1135      isUnion = true;
1136    BaseQuals = BaseExpr->getType().getQualifiers();
1137  } else {
1138    LValue BaseLV = EmitLValue(BaseExpr);
1139    if (BaseLV.isNonGC())
1140      isNonGC = true;
1141    // FIXME: this isn't right for bitfields.
1142    BaseValue = BaseLV.getAddress();
1143    QualType BaseTy = BaseExpr->getType();
1144    if (BaseTy->isUnionType())
1145      isUnion = true;
1146    BaseQuals = BaseTy.getQualifiers();
1147  }
1148
1149  NamedDecl *ND = E->getMemberDecl();
1150  if (FieldDecl *Field = dyn_cast<FieldDecl>(ND)) {
1151    LValue LV = EmitLValueForField(BaseValue, Field, isUnion,
1152                                   BaseQuals.getCVRQualifiers());
1153    LValue::SetObjCNonGC(LV, isNonGC);
1154    setObjCGCLValueClass(getContext(), E, LV);
1155    return LV;
1156  }
1157
1158  if (VarDecl *VD = dyn_cast<VarDecl>(ND))
1159    return EmitGlobalVarDeclLValue(*this, E, VD);
1160
1161  assert(false && "Unhandled member declaration!");
1162  return LValue();
1163}
1164
1165LValue CodeGenFunction::EmitLValueForBitfield(llvm::Value* BaseValue,
1166                                              FieldDecl* Field,
1167                                              unsigned CVRQualifiers) {
1168  CodeGenTypes::BitFieldInfo Info = CGM.getTypes().getBitFieldInfo(Field);
1169
1170  // FIXME: CodeGenTypes should expose a method to get the appropriate type for
1171  // FieldTy (the appropriate type is ABI-dependent).
1172  const llvm::Type *FieldTy =
1173    CGM.getTypes().ConvertTypeForMem(Field->getType());
1174  const llvm::PointerType *BaseTy =
1175  cast<llvm::PointerType>(BaseValue->getType());
1176  unsigned AS = BaseTy->getAddressSpace();
1177  BaseValue = Builder.CreateBitCast(BaseValue,
1178                                    llvm::PointerType::get(FieldTy, AS),
1179                                    "tmp");
1180
1181  llvm::Value *Idx =
1182    llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), Info.FieldNo);
1183  llvm::Value *V = Builder.CreateGEP(BaseValue, Idx, "tmp");
1184
1185  return LValue::MakeBitfield(V, Info.Start, Info.Size,
1186                              Field->getType()->isSignedIntegerType(),
1187                            Field->getType().getCVRQualifiers()|CVRQualifiers);
1188}
1189
1190LValue CodeGenFunction::EmitLValueForField(llvm::Value* BaseValue,
1191                                           FieldDecl* Field,
1192                                           bool isUnion,
1193                                           unsigned CVRQualifiers) {
1194  if (Field->isBitField())
1195    return EmitLValueForBitfield(BaseValue, Field, CVRQualifiers);
1196
1197  unsigned idx = CGM.getTypes().getLLVMFieldNo(Field);
1198  llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx, "tmp");
1199
1200  // Match union field type.
1201  if (isUnion) {
1202    const llvm::Type *FieldTy =
1203      CGM.getTypes().ConvertTypeForMem(Field->getType());
1204    const llvm::PointerType * BaseTy =
1205      cast<llvm::PointerType>(BaseValue->getType());
1206    unsigned AS = BaseTy->getAddressSpace();
1207    V = Builder.CreateBitCast(V,
1208                              llvm::PointerType::get(FieldTy, AS),
1209                              "tmp");
1210  }
1211  if (Field->getType()->isReferenceType())
1212    V = Builder.CreateLoad(V, "tmp");
1213
1214  Qualifiers Quals = MakeQualifiers(Field->getType());
1215  Quals.addCVRQualifiers(CVRQualifiers);
1216  // __weak attribute on a field is ignored.
1217  if (Quals.getObjCGCAttr() == Qualifiers::Weak)
1218    Quals.removeObjCGCAttr();
1219
1220  return LValue::MakeAddr(V, Quals);
1221}
1222
1223LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr* E){
1224  const llvm::Type *LTy = ConvertType(E->getType());
1225  llvm::Value *DeclPtr = CreateTempAlloca(LTy, ".compoundliteral");
1226
1227  const Expr* InitExpr = E->getInitializer();
1228  LValue Result = LValue::MakeAddr(DeclPtr, MakeQualifiers(E->getType()));
1229
1230  if (E->getType()->isComplexType())
1231    EmitComplexExprIntoAddr(InitExpr, DeclPtr, false);
1232  else if (hasAggregateLLVMType(E->getType()))
1233    EmitAnyExpr(InitExpr, DeclPtr, false);
1234  else
1235    EmitStoreThroughLValue(EmitAnyExpr(InitExpr), Result, E->getType());
1236
1237  return Result;
1238}
1239
1240LValue
1241CodeGenFunction::EmitConditionalOperatorLValue(const ConditionalOperator* E) {
1242  if (E->isLvalue(getContext()) == Expr::LV_Valid) {
1243    llvm::BasicBlock *LHSBlock = createBasicBlock("cond.true");
1244    llvm::BasicBlock *RHSBlock = createBasicBlock("cond.false");
1245    llvm::BasicBlock *ContBlock = createBasicBlock("cond.end");
1246
1247    llvm::Value *Cond = EvaluateExprAsBool(E->getCond());
1248    Builder.CreateCondBr(Cond, LHSBlock, RHSBlock);
1249
1250    EmitBlock(LHSBlock);
1251
1252    LValue LHS = EmitLValue(E->getLHS());
1253    if (!LHS.isSimple())
1254      return EmitUnsupportedLValue(E, "conditional operator");
1255
1256    llvm::Value *Temp = CreateTempAlloca(LHS.getAddress()->getType(),"condtmp");
1257    Builder.CreateStore(LHS.getAddress(), Temp);
1258    EmitBranch(ContBlock);
1259
1260    EmitBlock(RHSBlock);
1261    LValue RHS = EmitLValue(E->getRHS());
1262    if (!RHS.isSimple())
1263      return EmitUnsupportedLValue(E, "conditional operator");
1264
1265    Builder.CreateStore(RHS.getAddress(), Temp);
1266    EmitBranch(ContBlock);
1267
1268    EmitBlock(ContBlock);
1269
1270    Temp = Builder.CreateLoad(Temp, "lv");
1271    return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1272  }
1273
1274  // ?: here should be an aggregate.
1275  assert((hasAggregateLLVMType(E->getType()) &&
1276          !E->getType()->isAnyComplexType()) &&
1277         "Unexpected conditional operator!");
1278
1279  llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType()));
1280  EmitAggExpr(E, Temp, false);
1281
1282  return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1283}
1284
1285/// EmitCastLValue - Casts are never lvalues.  If a cast is needed by the code
1286/// generator in an lvalue context, then it must mean that we need the address
1287/// of an aggregate in order to access one of its fields.  This can happen for
1288/// all the reasons that casts are permitted with aggregate result, including
1289/// noop aggregate casts, and cast from scalar to union.
1290LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
1291  switch (E->getCastKind()) {
1292  default:
1293    // If this is an lvalue cast, treat it as a no-op.
1294    // FIXME: We shouldn't need to check for this explicitly!
1295    if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
1296      if (ICE->isLvalueCast())
1297        return EmitLValue(E->getSubExpr());
1298
1299    assert(0 && "Unhandled cast!");
1300
1301  case CastExpr::CK_NoOp:
1302  case CastExpr::CK_ConstructorConversion:
1303  case CastExpr::CK_UserDefinedConversion:
1304    return EmitLValue(E->getSubExpr());
1305
1306  case CastExpr::CK_DerivedToBase: {
1307    const RecordType *DerivedClassTy =
1308      E->getSubExpr()->getType()->getAs<RecordType>();
1309    CXXRecordDecl *DerivedClassDecl =
1310      cast<CXXRecordDecl>(DerivedClassTy->getDecl());
1311
1312    const RecordType *BaseClassTy = E->getType()->getAs<RecordType>();
1313    CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseClassTy->getDecl());
1314
1315    LValue LV = EmitLValue(E->getSubExpr());
1316
1317    // Perform the derived-to-base conversion
1318    llvm::Value *Base =
1319      GetAddressCXXOfBaseClass(LV.getAddress(), DerivedClassDecl,
1320                               BaseClassDecl, /*NullCheckValue=*/false);
1321
1322    return LValue::MakeAddr(Base, MakeQualifiers(E->getType()));
1323  }
1324
1325  case CastExpr::CK_ToUnion: {
1326    llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType()));
1327    EmitAnyExpr(E->getSubExpr(), Temp, false);
1328
1329    return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1330    }
1331  }
1332}
1333
1334LValue CodeGenFunction::EmitNullInitializationLValue(
1335                                              const CXXZeroInitValueExpr *E) {
1336  QualType Ty = E->getType();
1337  const llvm::Type *LTy = ConvertTypeForMem(Ty);
1338  llvm::AllocaInst *Alloc = CreateTempAlloca(LTy);
1339  unsigned Align = getContext().getTypeAlign(Ty)/8;
1340  Alloc->setAlignment(Align);
1341  LValue lvalue = LValue::MakeAddr(Alloc, Qualifiers());
1342  EmitMemSetToZero(lvalue.getAddress(), Ty);
1343  return lvalue;
1344}
1345
1346//===--------------------------------------------------------------------===//
1347//                             Expression Emission
1348//===--------------------------------------------------------------------===//
1349
1350
1351RValue CodeGenFunction::EmitCallExpr(const CallExpr *E) {
1352  // Builtins never have block type.
1353  if (E->getCallee()->getType()->isBlockPointerType())
1354    return EmitBlockCallExpr(E);
1355
1356  if (const CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(E))
1357    return EmitCXXMemberCallExpr(CE);
1358
1359  const Decl *TargetDecl = 0;
1360  if (const ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E->getCallee())) {
1361    if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CE->getSubExpr())) {
1362      TargetDecl = DRE->getDecl();
1363      if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(TargetDecl))
1364        if (unsigned builtinID = FD->getBuiltinID())
1365          return EmitBuiltinExpr(FD, builtinID, E);
1366    }
1367  }
1368
1369  if (const CXXOperatorCallExpr *CE = dyn_cast<CXXOperatorCallExpr>(E))
1370    if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(TargetDecl))
1371      return EmitCXXOperatorMemberCallExpr(CE, MD);
1372
1373  if (isa<CXXPseudoDestructorExpr>(E->getCallee())) {
1374    // C++ [expr.pseudo]p1:
1375    //   The result shall only be used as the operand for the function call
1376    //   operator (), and the result of such a call has type void. The only
1377    //   effect is the evaluation of the postfix-expression before the dot or
1378    //   arrow.
1379    EmitScalarExpr(E->getCallee());
1380    return RValue::get(0);
1381  }
1382
1383  llvm::Value *Callee = EmitScalarExpr(E->getCallee());
1384  return EmitCall(Callee, E->getCallee()->getType(),
1385                  E->arg_begin(), E->arg_end(), TargetDecl);
1386}
1387
1388LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
1389  // Comma expressions just emit their LHS then their RHS as an l-value.
1390  if (E->getOpcode() == BinaryOperator::Comma) {
1391    EmitAnyExpr(E->getLHS());
1392    return EmitLValue(E->getRHS());
1393  }
1394
1395  if (E->getOpcode() == BinaryOperator::PtrMemD ||
1396      E->getOpcode() == BinaryOperator::PtrMemI)
1397    return EmitPointerToDataMemberBinaryExpr(E);
1398
1399  // Can only get l-value for binary operator expressions which are a
1400  // simple assignment of aggregate type.
1401  if (E->getOpcode() != BinaryOperator::Assign)
1402    return EmitUnsupportedLValue(E, "binary l-value expression");
1403
1404  if (!hasAggregateLLVMType(E->getType())) {
1405    // Emit the LHS as an l-value.
1406    LValue LV = EmitLValue(E->getLHS());
1407
1408    llvm::Value *RHS = EmitScalarExpr(E->getRHS());
1409    EmitStoreOfScalar(RHS, LV.getAddress(), LV.isVolatileQualified(),
1410                      E->getType());
1411    return LV;
1412  }
1413
1414  llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType()));
1415  EmitAggExpr(E, Temp, false);
1416  // FIXME: Are these qualifiers correct?
1417  return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1418}
1419
1420LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
1421  RValue RV = EmitCallExpr(E);
1422
1423  if (!RV.isScalar())
1424    return LValue::MakeAddr(RV.getAggregateAddr(),MakeQualifiers(E->getType()));
1425
1426  assert(E->getCallReturnType()->isReferenceType() &&
1427         "Can't have a scalar return unless the return type is a "
1428         "reference type!");
1429
1430  return LValue::MakeAddr(RV.getScalarVal(), MakeQualifiers(E->getType()));
1431}
1432
1433LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
1434  // FIXME: This shouldn't require another copy.
1435  llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType()));
1436  EmitAggExpr(E, Temp, false);
1437  return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1438}
1439
1440LValue
1441CodeGenFunction::EmitCXXConditionDeclLValue(const CXXConditionDeclExpr *E) {
1442  EmitLocalBlockVarDecl(*E->getVarDecl());
1443  return EmitDeclRefLValue(E);
1444}
1445
1446LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
1447  llvm::Value *Temp = CreateTempAlloca(ConvertTypeForMem(E->getType()), "tmp");
1448  EmitCXXConstructExpr(Temp, E);
1449  return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1450}
1451
1452LValue
1453CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
1454  LValue LV = EmitLValue(E->getSubExpr());
1455  PushCXXTemporary(E->getTemporary(), LV.getAddress());
1456  return LV;
1457}
1458
1459LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
1460  // Can only get l-value for message expression returning aggregate type
1461  RValue RV = EmitObjCMessageExpr(E);
1462  // FIXME: can this be volatile?
1463  return LValue::MakeAddr(RV.getAggregateAddr(), MakeQualifiers(E->getType()));
1464}
1465
1466llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
1467                                             const ObjCIvarDecl *Ivar) {
1468  return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
1469}
1470
1471LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
1472                                          llvm::Value *BaseValue,
1473                                          const ObjCIvarDecl *Ivar,
1474                                          unsigned CVRQualifiers) {
1475  return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
1476                                                   Ivar, CVRQualifiers);
1477}
1478
1479LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
1480  // FIXME: A lot of the code below could be shared with EmitMemberExpr.
1481  llvm::Value *BaseValue = 0;
1482  const Expr *BaseExpr = E->getBase();
1483  Qualifiers BaseQuals;
1484  QualType ObjectTy;
1485  if (E->isArrow()) {
1486    BaseValue = EmitScalarExpr(BaseExpr);
1487    ObjectTy = BaseExpr->getType()->getPointeeType();
1488    BaseQuals = ObjectTy.getQualifiers();
1489  } else {
1490    LValue BaseLV = EmitLValue(BaseExpr);
1491    // FIXME: this isn't right for bitfields.
1492    BaseValue = BaseLV.getAddress();
1493    ObjectTy = BaseExpr->getType();
1494    BaseQuals = ObjectTy.getQualifiers();
1495  }
1496
1497  LValue LV =
1498    EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
1499                      BaseQuals.getCVRQualifiers());
1500  setObjCGCLValueClass(getContext(), E, LV);
1501  return LV;
1502}
1503
1504LValue
1505CodeGenFunction::EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E) {
1506  // This is a special l-value that just issues sends when we load or store
1507  // through it.
1508  return LValue::MakePropertyRef(E, E->getType().getCVRQualifiers());
1509}
1510
1511LValue CodeGenFunction::EmitObjCKVCRefLValue(
1512                                const ObjCImplicitSetterGetterRefExpr *E) {
1513  // This is a special l-value that just issues sends when we load or store
1514  // through it.
1515  return LValue::MakeKVCRef(E, E->getType().getCVRQualifiers());
1516}
1517
1518LValue CodeGenFunction::EmitObjCSuperExprLValue(const ObjCSuperExpr *E) {
1519  return EmitUnsupportedLValue(E, "use of super");
1520}
1521
1522LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
1523  // Can only get l-value for message expression returning aggregate type
1524  RValue RV = EmitAnyExprToTemp(E);
1525  // FIXME: can this be volatile?
1526  return LValue::MakeAddr(RV.getAggregateAddr(), MakeQualifiers(E->getType()));
1527}
1528
1529
1530LValue CodeGenFunction::EmitPointerToDataMemberLValue(const FieldDecl *Field) {
1531  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Field->getDeclContext());
1532  QualType NNSpecTy =
1533    getContext().getCanonicalType(
1534      getContext().getTypeDeclType(const_cast<CXXRecordDecl*>(ClassDecl)));
1535  NNSpecTy = getContext().getPointerType(NNSpecTy);
1536  llvm::Value *V = llvm::Constant::getNullValue(ConvertType(NNSpecTy));
1537  LValue MemExpLV = EmitLValueForField(V, const_cast<FieldDecl*>(Field),
1538                                       /*isUnion*/false, /*Qualifiers*/0);
1539  const llvm::Type *ResultType = ConvertType(getContext().getPointerDiffType());
1540  V = Builder.CreatePtrToInt(MemExpLV.getAddress(), ResultType, "datamember");
1541  return LValue::MakeAddr(V, MakeQualifiers(Field->getType()));
1542}
1543
1544RValue CodeGenFunction::EmitCall(llvm::Value *Callee, QualType CalleeType,
1545                                 CallExpr::const_arg_iterator ArgBeg,
1546                                 CallExpr::const_arg_iterator ArgEnd,
1547                                 const Decl *TargetDecl) {
1548  // Get the actual function type. The callee type will always be a pointer to
1549  // function type or a block pointer type.
1550  assert(CalleeType->isFunctionPointerType() &&
1551         "Call must have function pointer type!");
1552
1553  CalleeType = getContext().getCanonicalType(CalleeType);
1554
1555  QualType FnType = cast<PointerType>(CalleeType)->getPointeeType();
1556  QualType ResultType = cast<FunctionType>(FnType)->getResultType();
1557
1558  CallArgList Args;
1559  EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), ArgBeg, ArgEnd);
1560
1561  // FIXME: We should not need to do this, it should be part of the function
1562  // type.
1563  unsigned CallingConvention = 0;
1564  if (const llvm::Function *F =
1565      dyn_cast<llvm::Function>(Callee->stripPointerCasts()))
1566    CallingConvention = F->getCallingConv();
1567  return EmitCall(CGM.getTypes().getFunctionInfo(ResultType, Args,
1568                                                 CallingConvention),
1569                  Callee, Args, TargetDecl);
1570}
1571
1572LValue CodeGenFunction::
1573EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
1574  llvm::Value *BaseV = EmitLValue(E->getLHS()).getAddress();
1575  if (E->getOpcode() == BinaryOperator::PtrMemI)
1576    BaseV = Builder.CreateLoad(BaseV, "indir.ptr");
1577  const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(getLLVMContext());
1578  BaseV = Builder.CreateBitCast(BaseV, i8Ty);
1579  LValue RHSLV = EmitLValue(E->getRHS());
1580  llvm::Value *OffsetV =
1581    EmitLoadOfLValue(RHSLV, E->getRHS()->getType()).getScalarVal();
1582  const llvm::Type* ResultType = ConvertType(getContext().getPointerDiffType());
1583  OffsetV = Builder.CreateBitCast(OffsetV, ResultType);
1584  llvm::Value *AddV = Builder.CreateInBoundsGEP(BaseV, OffsetV, "add.ptr");
1585
1586  QualType Ty = E->getRHS()->getType();
1587  Ty = Ty->getAs<MemberPointerType>()->getPointeeType();
1588
1589  const llvm::Type *PType = ConvertType(getContext().getPointerType(Ty));
1590  AddV = Builder.CreateBitCast(AddV, PType);
1591  return LValue::MakeAddr(AddV, MakeQualifiers(Ty));
1592}
1593
1594