CGExpr.cpp revision 52f08bcbb81c750ed62b53ed0b34aff16143b877 
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    if (ShouldDestroyTemporaries) {
88      // Keep track of the current cleanup stack depth.
89      OldNumLiveTemporaries = LiveTemporaries.size();
90    }
91
92    E = TE->getSubExpr();
93  }
94
95  RValue Val;
96  if (E->isLvalue(getContext()) == Expr::LV_Valid) {
97    // Emit the expr as an lvalue.
98    LValue LV = EmitLValue(E);
99    if (LV.isSimple())
100      return RValue::get(LV.getAddress());
101    Val = EmitLoadOfLValue(LV, E->getType());
102
103    if (ShouldDestroyTemporaries) {
104      // Pop temporaries.
105      while (LiveTemporaries.size() > OldNumLiveTemporaries)
106        PopCXXTemporary();
107    }
108  } else {
109    const CXXRecordDecl *BaseClassDecl = 0;
110    const CXXRecordDecl *DerivedClassDecl = 0;
111
112    if (const CastExpr *CE =
113          dyn_cast<CastExpr>(E->IgnoreParenNoopCasts(getContext()))) {
114      if (CE->getCastKind() == CastExpr::CK_DerivedToBase) {
115        E = CE->getSubExpr();
116
117        BaseClassDecl =
118          cast<CXXRecordDecl>(CE->getType()->getAs<RecordType>()->getDecl());
119        DerivedClassDecl =
120          cast<CXXRecordDecl>(E->getType()->getAs<RecordType>()->getDecl());
121      }
122    }
123
124    Val = EmitAnyExprToTemp(E, /*IsAggLocVolatile=*/false,
125                            IsInitializer);
126
127    if (ShouldDestroyTemporaries) {
128      // Pop temporaries.
129      while (LiveTemporaries.size() > OldNumLiveTemporaries)
130        PopCXXTemporary();
131    }
132
133    if (IsInitializer) {
134      // We might have to destroy the temporary variable.
135      if (const RecordType *RT = E->getType()->getAs<RecordType>()) {
136        if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
137          if (!ClassDecl->hasTrivialDestructor()) {
138            const CXXDestructorDecl *Dtor =
139              ClassDecl->getDestructor(getContext());
140
141            CleanupScope scope(*this);
142            EmitCXXDestructorCall(Dtor, Dtor_Complete, Val.getAggregateAddr());
143          }
144        }
145      }
146    }
147
148    // Check if need to perform the derived-to-base cast.
149    if (BaseClassDecl) {
150      llvm::Value *Derived = Val.getAggregateAddr();
151
152      llvm::Value *Base =
153        GetAddressCXXOfBaseClass(Derived, DerivedClassDecl, BaseClassDecl,
154                                 /*NullCheckValue=*/false);
155      return RValue::get(Base);
156    }
157  }
158
159  if (Val.isAggregate()) {
160    Val = RValue::get(Val.getAggregateAddr());
161  } else {
162    // Create a temporary variable that we can bind the reference to.
163    llvm::Value *Temp = CreateTempAlloca(ConvertTypeForMem(E->getType()),
164                                         "reftmp");
165    if (Val.isScalar())
166      EmitStoreOfScalar(Val.getScalarVal(), Temp, false, E->getType());
167    else
168      StoreComplexToAddr(Val.getComplexVal(), Temp, false);
169    Val = RValue::get(Temp);
170  }
171
172  return Val;
173}
174
175
176/// getAccessedFieldNo - Given an encoded value and a result number, return the
177/// input field number being accessed.
178unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
179                                             const llvm::Constant *Elts) {
180  if (isa<llvm::ConstantAggregateZero>(Elts))
181    return 0;
182
183  return cast<llvm::ConstantInt>(Elts->getOperand(Idx))->getZExtValue();
184}
185
186
187//===----------------------------------------------------------------------===//
188//                         LValue Expression Emission
189//===----------------------------------------------------------------------===//
190
191RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
192  if (Ty->isVoidType()) {
193    return RValue::get(0);
194  } else if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
195    const llvm::Type *EltTy = ConvertType(CTy->getElementType());
196    llvm::Value *U = llvm::UndefValue::get(EltTy);
197    return RValue::getComplex(std::make_pair(U, U));
198  } else if (hasAggregateLLVMType(Ty)) {
199    const llvm::Type *LTy = llvm::PointerType::getUnqual(ConvertType(Ty));
200    return RValue::getAggregate(llvm::UndefValue::get(LTy));
201  } else {
202    return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
203  }
204}
205
206RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
207                                              const char *Name) {
208  ErrorUnsupported(E, Name);
209  return GetUndefRValue(E->getType());
210}
211
212LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
213                                              const char *Name) {
214  ErrorUnsupported(E, Name);
215  llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
216  return LValue::MakeAddr(llvm::UndefValue::get(Ty),
217                          MakeQualifiers(E->getType()));
218}
219
220/// EmitLValue - Emit code to compute a designator that specifies the location
221/// of the expression.
222///
223/// This can return one of two things: a simple address or a bitfield reference.
224/// In either case, the LLVM Value* in the LValue structure is guaranteed to be
225/// an LLVM pointer type.
226///
227/// If this returns a bitfield reference, nothing about the pointee type of the
228/// LLVM value is known: For example, it may not be a pointer to an integer.
229///
230/// If this returns a normal address, and if the lvalue's C type is fixed size,
231/// this method guarantees that the returned pointer type will point to an LLVM
232/// type of the same size of the lvalue's type.  If the lvalue has a variable
233/// length type, this is not possible.
234///
235LValue CodeGenFunction::EmitLValue(const Expr *E) {
236  switch (E->getStmtClass()) {
237  default: return EmitUnsupportedLValue(E, "l-value expression");
238
239  case Expr::BinaryOperatorClass:
240    return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
241  case Expr::CallExprClass:
242  case Expr::CXXMemberCallExprClass:
243  case Expr::CXXOperatorCallExprClass:
244    return EmitCallExprLValue(cast<CallExpr>(E));
245  case Expr::VAArgExprClass:
246    return EmitVAArgExprLValue(cast<VAArgExpr>(E));
247  case Expr::DeclRefExprClass:
248    return EmitDeclRefLValue(cast<DeclRefExpr>(E));
249  case Expr::ParenExprClass:return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
250  case Expr::PredefinedExprClass:
251    return EmitPredefinedLValue(cast<PredefinedExpr>(E));
252  case Expr::StringLiteralClass:
253    return EmitStringLiteralLValue(cast<StringLiteral>(E));
254  case Expr::ObjCEncodeExprClass:
255    return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
256
257  case Expr::BlockDeclRefExprClass:
258    return EmitBlockDeclRefLValue(cast<BlockDeclRefExpr>(E));
259
260  case Expr::CXXConditionDeclExprClass:
261    return EmitCXXConditionDeclLValue(cast<CXXConditionDeclExpr>(E));
262  case Expr::CXXTemporaryObjectExprClass:
263  case Expr::CXXConstructExprClass:
264    return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
265  case Expr::CXXBindTemporaryExprClass:
266    return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
267  case Expr::CXXExprWithTemporariesClass:
268    return EmitCXXExprWithTemporariesLValue(cast<CXXExprWithTemporaries>(E));
269
270  case Expr::ObjCMessageExprClass:
271    return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
272  case Expr::ObjCIvarRefExprClass:
273    return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
274  case Expr::ObjCPropertyRefExprClass:
275    return EmitObjCPropertyRefLValue(cast<ObjCPropertyRefExpr>(E));
276  case Expr::ObjCImplicitSetterGetterRefExprClass:
277    return EmitObjCKVCRefLValue(cast<ObjCImplicitSetterGetterRefExpr>(E));
278  case Expr::ObjCSuperExprClass:
279    return EmitObjCSuperExprLValue(cast<ObjCSuperExpr>(E));
280
281  case Expr::StmtExprClass:
282    return EmitStmtExprLValue(cast<StmtExpr>(E));
283  case Expr::UnaryOperatorClass:
284    return EmitUnaryOpLValue(cast<UnaryOperator>(E));
285  case Expr::ArraySubscriptExprClass:
286    return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
287  case Expr::ExtVectorElementExprClass:
288    return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
289  case Expr::MemberExprClass:
290    return EmitMemberExpr(cast<MemberExpr>(E));
291  case Expr::CompoundLiteralExprClass:
292    return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
293  case Expr::ConditionalOperatorClass:
294    return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
295  case Expr::ChooseExprClass:
296    return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(getContext()));
297  case Expr::ImplicitCastExprClass:
298  case Expr::CStyleCastExprClass:
299  case Expr::CXXFunctionalCastExprClass:
300  case Expr::CXXStaticCastExprClass:
301  case Expr::CXXDynamicCastExprClass:
302  case Expr::CXXReinterpretCastExprClass:
303  case Expr::CXXConstCastExprClass:
304    return EmitCastLValue(cast<CastExpr>(E));
305  case Expr::CXXZeroInitValueExprClass:
306    return EmitNullInitializationLValue(cast<CXXZeroInitValueExpr>(E));
307  }
308}
309
310llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile,
311                                               QualType Ty) {
312  llvm::Value *V = Builder.CreateLoad(Addr, Volatile, "tmp");
313
314  // Bool can have different representation in memory than in registers.
315  if (Ty->isBooleanType())
316    if (V->getType() != llvm::Type::getInt1Ty(VMContext))
317      V = Builder.CreateTrunc(V, llvm::Type::getInt1Ty(VMContext), "tobool");
318
319  return V;
320}
321
322void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr,
323                                        bool Volatile, QualType Ty) {
324
325  if (Ty->isBooleanType()) {
326    // Bool can have different representation in memory than in registers.
327    const llvm::Type *SrcTy = Value->getType();
328    const llvm::PointerType *DstPtr = cast<llvm::PointerType>(Addr->getType());
329    if (DstPtr->getElementType() != SrcTy) {
330      const llvm::Type *MemTy =
331        llvm::PointerType::get(SrcTy, DstPtr->getAddressSpace());
332      Addr = Builder.CreateBitCast(Addr, MemTy, "storetmp");
333    }
334  }
335  Builder.CreateStore(Value, Addr, Volatile);
336}
337
338/// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
339/// method emits the address of the lvalue, then loads the result as an rvalue,
340/// returning the rvalue.
341RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, QualType ExprType) {
342  if (LV.isObjCWeak()) {
343    // load of a __weak object.
344    llvm::Value *AddrWeakObj = LV.getAddress();
345    llvm::Value *read_weak = CGM.getObjCRuntime().EmitObjCWeakRead(*this,
346                                                                   AddrWeakObj);
347    return RValue::get(read_weak);
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    if (Dst.isKVCRef())
525      return EmitStoreThroughKVCRefLValue(Src, Dst, Ty);
526
527    assert(0 && "Unknown LValue type");
528  }
529
530  if (Dst.isObjCWeak() && !Dst.isNonGC()) {
531    // load of a __weak object.
532    llvm::Value *LvalueDst = Dst.getAddress();
533    llvm::Value *src = Src.getScalarVal();
534     CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
535    return;
536  }
537
538  if (Dst.isObjCStrong() && !Dst.isNonGC()) {
539    // load of a __strong object.
540    llvm::Value *LvalueDst = Dst.getAddress();
541    llvm::Value *src = Src.getScalarVal();
542    if (Dst.isObjCIvar()) {
543      assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
544      const llvm::Type *ResultType = ConvertType(getContext().LongTy);
545      llvm::Value *RHS = EmitScalarExpr(Dst.getBaseIvarExp());
546      llvm::Value *dst = RHS;
547      RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
548      llvm::Value *LHS =
549        Builder.CreatePtrToInt(LvalueDst, ResultType, "sub.ptr.lhs.cast");
550      llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
551      CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
552                                              BytesBetween);
553    }
554    else if (Dst.isGlobalObjCRef())
555      CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst);
556    else
557      CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
558    return;
559  }
560
561  assert(Src.isScalar() && "Can't emit an agg store with this method");
562  EmitStoreOfScalar(Src.getScalarVal(), Dst.getAddress(),
563                    Dst.isVolatileQualified(), Ty);
564}
565
566void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
567                                                     QualType Ty,
568                                                     llvm::Value **Result) {
569  unsigned StartBit = Dst.getBitfieldStartBit();
570  unsigned BitfieldSize = Dst.getBitfieldSize();
571  llvm::Value *Ptr = Dst.getBitfieldAddr();
572
573  const llvm::Type *EltTy =
574    cast<llvm::PointerType>(Ptr->getType())->getElementType();
575  unsigned EltTySize = CGM.getTargetData().getTypeSizeInBits(EltTy);
576
577  // Get the new value, cast to the appropriate type and masked to exactly the
578  // size of the bit-field.
579  llvm::Value *SrcVal = Src.getScalarVal();
580  llvm::Value *NewVal = Builder.CreateIntCast(SrcVal, EltTy, false, "tmp");
581  llvm::Constant *Mask = llvm::ConstantInt::get(VMContext,
582                           llvm::APInt::getLowBitsSet(EltTySize, BitfieldSize));
583  NewVal = Builder.CreateAnd(NewVal, Mask, "bf.value");
584
585  // Return the new value of the bit-field, if requested.
586  if (Result) {
587    // Cast back to the proper type for result.
588    const llvm::Type *SrcTy = SrcVal->getType();
589    llvm::Value *SrcTrunc = Builder.CreateIntCast(NewVal, SrcTy, false,
590                                                  "bf.reload.val");
591
592    // Sign extend if necessary.
593    if (Dst.isBitfieldSigned()) {
594      unsigned SrcTySize = CGM.getTargetData().getTypeSizeInBits(SrcTy);
595      llvm::Value *ExtraBits = llvm::ConstantInt::get(SrcTy,
596                                                      SrcTySize - BitfieldSize);
597      SrcTrunc = Builder.CreateAShr(Builder.CreateShl(SrcTrunc, ExtraBits),
598                                    ExtraBits, "bf.reload.sext");
599    }
600
601    *Result = SrcTrunc;
602  }
603
604  // In some cases the bitfield may straddle two memory locations.  Emit the low
605  // part first and check to see if the high needs to be done.
606  unsigned LowBits = std::min(BitfieldSize, EltTySize - StartBit);
607  llvm::Value *LowVal = Builder.CreateLoad(Ptr, Dst.isVolatileQualified(),
608                                           "bf.prev.low");
609
610  // Compute the mask for zero-ing the low part of this bitfield.
611  llvm::Constant *InvMask =
612    llvm::ConstantInt::get(VMContext,
613             ~llvm::APInt::getBitsSet(EltTySize, StartBit, StartBit + LowBits));
614
615  // Compute the new low part as
616  //   LowVal = (LowVal & InvMask) | (NewVal << StartBit),
617  // with the shift of NewVal implicitly stripping the high bits.
618  llvm::Value *NewLowVal =
619    Builder.CreateShl(NewVal, llvm::ConstantInt::get(EltTy, StartBit),
620                      "bf.value.lo");
621  LowVal = Builder.CreateAnd(LowVal, InvMask, "bf.prev.lo.cleared");
622  LowVal = Builder.CreateOr(LowVal, NewLowVal, "bf.new.lo");
623
624  // Write back.
625  Builder.CreateStore(LowVal, Ptr, Dst.isVolatileQualified());
626
627  // If the low part doesn't cover the bitfield emit a high part.
628  if (LowBits < BitfieldSize) {
629    unsigned HighBits = BitfieldSize - LowBits;
630    llvm::Value *HighPtr =  Builder.CreateGEP(Ptr, llvm::ConstantInt::get(
631                            llvm::Type::getInt32Ty(VMContext), 1), "bf.ptr.hi");
632    llvm::Value *HighVal = Builder.CreateLoad(HighPtr,
633                                              Dst.isVolatileQualified(),
634                                              "bf.prev.hi");
635
636    // Compute the mask for zero-ing the high part of this bitfield.
637    llvm::Constant *InvMask =
638      llvm::ConstantInt::get(VMContext, ~llvm::APInt::getLowBitsSet(EltTySize,
639                               HighBits));
640
641    // Compute the new high part as
642    //   HighVal = (HighVal & InvMask) | (NewVal lshr LowBits),
643    // where the high bits of NewVal have already been cleared and the
644    // shift stripping the low bits.
645    llvm::Value *NewHighVal =
646      Builder.CreateLShr(NewVal, llvm::ConstantInt::get(EltTy, LowBits),
647                        "bf.value.high");
648    HighVal = Builder.CreateAnd(HighVal, InvMask, "bf.prev.hi.cleared");
649    HighVal = Builder.CreateOr(HighVal, NewHighVal, "bf.new.hi");
650
651    // Write back.
652    Builder.CreateStore(HighVal, HighPtr, Dst.isVolatileQualified());
653  }
654}
655
656void CodeGenFunction::EmitStoreThroughPropertyRefLValue(RValue Src,
657                                                        LValue Dst,
658                                                        QualType Ty) {
659  EmitObjCPropertySet(Dst.getPropertyRefExpr(), Src);
660}
661
662void CodeGenFunction::EmitStoreThroughKVCRefLValue(RValue Src,
663                                                   LValue Dst,
664                                                   QualType Ty) {
665  EmitObjCPropertySet(Dst.getKVCRefExpr(), Src);
666}
667
668void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
669                                                               LValue Dst,
670                                                               QualType Ty) {
671  // This access turns into a read/modify/write of the vector.  Load the input
672  // value now.
673  llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddr(),
674                                        Dst.isVolatileQualified(), "tmp");
675  const llvm::Constant *Elts = Dst.getExtVectorElts();
676
677  llvm::Value *SrcVal = Src.getScalarVal();
678
679  if (const VectorType *VTy = Ty->getAs<VectorType>()) {
680    unsigned NumSrcElts = VTy->getNumElements();
681    unsigned NumDstElts =
682       cast<llvm::VectorType>(Vec->getType())->getNumElements();
683    if (NumDstElts == NumSrcElts) {
684      // Use shuffle vector is the src and destination are the same number of
685      // elements and restore the vector mask since it is on the side it will be
686      // stored.
687      llvm::SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
688      for (unsigned i = 0; i != NumSrcElts; ++i) {
689        unsigned InIdx = getAccessedFieldNo(i, Elts);
690        Mask[InIdx] = llvm::ConstantInt::get(
691                                          llvm::Type::getInt32Ty(VMContext), i);
692      }
693
694      llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
695      Vec = Builder.CreateShuffleVector(SrcVal,
696                                        llvm::UndefValue::get(Vec->getType()),
697                                        MaskV, "tmp");
698    } else if (NumDstElts > NumSrcElts) {
699      // Extended the source vector to the same length and then shuffle it
700      // into the destination.
701      // FIXME: since we're shuffling with undef, can we just use the indices
702      //        into that?  This could be simpler.
703      llvm::SmallVector<llvm::Constant*, 4> ExtMask;
704      unsigned i;
705      for (i = 0; i != NumSrcElts; ++i)
706        ExtMask.push_back(llvm::ConstantInt::get(
707                                         llvm::Type::getInt32Ty(VMContext), i));
708      for (; i != NumDstElts; ++i)
709        ExtMask.push_back(llvm::UndefValue::get(
710                                            llvm::Type::getInt32Ty(VMContext)));
711      llvm::Value *ExtMaskV = llvm::ConstantVector::get(&ExtMask[0],
712                                                        ExtMask.size());
713      llvm::Value *ExtSrcVal =
714        Builder.CreateShuffleVector(SrcVal,
715                                    llvm::UndefValue::get(SrcVal->getType()),
716                                    ExtMaskV, "tmp");
717      // build identity
718      llvm::SmallVector<llvm::Constant*, 4> Mask;
719      for (unsigned i = 0; i != NumDstElts; ++i) {
720        Mask.push_back(llvm::ConstantInt::get(
721                                        llvm::Type::getInt32Ty(VMContext), i));
722      }
723      // modify when what gets shuffled in
724      for (unsigned i = 0; i != NumSrcElts; ++i) {
725        unsigned Idx = getAccessedFieldNo(i, Elts);
726        Mask[Idx] = llvm::ConstantInt::get(
727                               llvm::Type::getInt32Ty(VMContext), i+NumDstElts);
728      }
729      llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
730      Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV, "tmp");
731    } else {
732      // We should never shorten the vector
733      assert(0 && "unexpected shorten vector length");
734    }
735  } else {
736    // If the Src is a scalar (not a vector) it must be updating one element.
737    unsigned InIdx = getAccessedFieldNo(0, Elts);
738    llvm::Value *Elt = llvm::ConstantInt::get(
739                                      llvm::Type::getInt32Ty(VMContext), InIdx);
740    Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt, "tmp");
741  }
742
743  Builder.CreateStore(Vec, Dst.getExtVectorAddr(), Dst.isVolatileQualified());
744}
745
746// setObjCGCLValueClass - sets class of he lvalue for the purpose of
747// generating write-barries API. It is currently a global, ivar,
748// or neither.
749static
750void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E, LValue &LV) {
751  if (Ctx.getLangOptions().getGCMode() == LangOptions::NonGC)
752    return;
753
754  if (isa<ObjCIvarRefExpr>(E)) {
755    LV.SetObjCIvar(LV, true);
756    ObjCIvarRefExpr *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr*>(E));
757    LV.setBaseIvarExp(Exp->getBase());
758    LV.SetObjCArray(LV, E->getType()->isArrayType());
759    return;
760  }
761  if (const DeclRefExpr *Exp = dyn_cast<DeclRefExpr>(E)) {
762    if (const VarDecl *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
763      if ((VD->isBlockVarDecl() && !VD->hasLocalStorage()) ||
764          VD->isFileVarDecl())
765        LV.SetGlobalObjCRef(LV, true);
766    }
767    LV.SetObjCArray(LV, E->getType()->isArrayType());
768  }
769  else if (const UnaryOperator *Exp = dyn_cast<UnaryOperator>(E))
770    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
771  else 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  }
783  else if (const ImplicitCastExpr *Exp = dyn_cast<ImplicitCastExpr>(E))
784    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
785  else if (const CStyleCastExpr *Exp = dyn_cast<CStyleCastExpr>(E))
786    setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV);
787  else if (const ArraySubscriptExpr *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
788    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
789    if (LV.isObjCIvar() && !LV.isObjCArray())
790      // Using array syntax to assigning to what an ivar points to is not
791      // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
792      LV.SetObjCIvar(LV, false);
793    else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
794      // Using array syntax to assigning to what global points to is not
795      // same as assigning to the global itself. {id *G;} G[i] = 0;
796      LV.SetGlobalObjCRef(LV, false);
797  }
798  else if (const MemberExpr *Exp = dyn_cast<MemberExpr>(E)) {
799    setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
800    // We don't know if member is an 'ivar', but this flag is looked at
801    // only in the context of LV.isObjCIvar().
802    LV.SetObjCArray(LV, E->getType()->isArrayType());
803  }
804}
805
806LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
807  const VarDecl *VD = dyn_cast<VarDecl>(E->getDecl());
808
809  if (VD && (VD->isBlockVarDecl() || isa<ParmVarDecl>(VD) ||
810        isa<ImplicitParamDecl>(VD))) {
811    LValue LV;
812    bool NonGCable = VD->hasLocalStorage() &&
813      !VD->hasAttr<BlocksAttr>();
814    if (VD->hasExternalStorage()) {
815      llvm::Value *V = CGM.GetAddrOfGlobalVar(VD);
816      if (VD->getType()->isReferenceType())
817        V = Builder.CreateLoad(V, "tmp");
818      LV = LValue::MakeAddr(V, MakeQualifiers(E->getType()));
819    } else {
820      llvm::Value *V = LocalDeclMap[VD];
821      assert(V && "DeclRefExpr not entered in LocalDeclMap?");
822
823      Qualifiers Quals = MakeQualifiers(E->getType());
824      // local variables do not get their gc attribute set.
825      // local static?
826      if (NonGCable) Quals.removeObjCGCAttr();
827
828      if (VD->hasAttr<BlocksAttr>()) {
829        V = Builder.CreateStructGEP(V, 1, "forwarding");
830        V = Builder.CreateLoad(V, false);
831        V = Builder.CreateStructGEP(V, getByRefValueLLVMField(VD),
832                                    VD->getNameAsString());
833      }
834      if (VD->getType()->isReferenceType())
835        V = Builder.CreateLoad(V, "tmp");
836      LV = LValue::MakeAddr(V, Quals);
837    }
838    LValue::SetObjCNonGC(LV, NonGCable);
839    setObjCGCLValueClass(getContext(), E, LV);
840    return LV;
841  } else if (VD && VD->isFileVarDecl()) {
842    llvm::Value *V = CGM.GetAddrOfGlobalVar(VD);
843    if (VD->getType()->isReferenceType())
844      V = Builder.CreateLoad(V, "tmp");
845    LValue LV = LValue::MakeAddr(V, MakeQualifiers(E->getType()));
846    setObjCGCLValueClass(getContext(), E, LV);
847    return LV;
848  } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(E->getDecl())) {
849    llvm::Value* V = CGM.GetAddrOfFunction(FD);
850    if (!FD->hasPrototype()) {
851      if (const FunctionProtoType *Proto =
852              FD->getType()->getAs<FunctionProtoType>()) {
853        // Ugly case: for a K&R-style definition, the type of the definition
854        // isn't the same as the type of a use.  Correct for this with a
855        // bitcast.
856        QualType NoProtoType =
857            getContext().getFunctionNoProtoType(Proto->getResultType());
858        NoProtoType = getContext().getPointerType(NoProtoType);
859        V = Builder.CreateBitCast(V, ConvertType(NoProtoType), "tmp");
860      }
861    }
862    return LValue::MakeAddr(V, MakeQualifiers(E->getType()));
863  } else if (const ImplicitParamDecl *IPD =
864      dyn_cast<ImplicitParamDecl>(E->getDecl())) {
865    llvm::Value *V = LocalDeclMap[IPD];
866    assert(V && "BlockVarDecl not entered in LocalDeclMap?");
867    return LValue::MakeAddr(V, MakeQualifiers(E->getType()));
868  } else if (E->getQualifier()) {
869    // FIXME: the qualifier check does not seem sufficient here
870    return EmitPointerToDataMemberLValue(E);
871  }
872  assert(0 && "Unimp declref");
873  //an invalid LValue, but the assert will
874  //ensure that this point is never reached.
875  return LValue();
876}
877
878LValue CodeGenFunction::EmitBlockDeclRefLValue(const BlockDeclRefExpr *E) {
879  return LValue::MakeAddr(GetAddrOfBlockDecl(E), MakeQualifiers(E->getType()));
880}
881
882LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
883  // __extension__ doesn't affect lvalue-ness.
884  if (E->getOpcode() == UnaryOperator::Extension)
885    return EmitLValue(E->getSubExpr());
886
887  QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
888  switch (E->getOpcode()) {
889  default: assert(0 && "Unknown unary operator lvalue!");
890  case UnaryOperator::Deref:
891    {
892      QualType T = E->getSubExpr()->getType()->getPointeeType();
893      assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
894
895      Qualifiers Quals = MakeQualifiers(T);
896      Quals.setAddressSpace(ExprTy.getAddressSpace());
897
898      LValue LV = LValue::MakeAddr(EmitScalarExpr(E->getSubExpr()), Quals);
899     // We should not generate __weak write barrier on indirect reference
900     // of a pointer to object; as in void foo (__weak id *param); *param = 0;
901     // But, we continue to generate __strong write barrier on indirect write
902     // into a pointer to object.
903     if (getContext().getLangOptions().ObjC1 &&
904         getContext().getLangOptions().getGCMode() != LangOptions::NonGC &&
905         LV.isObjCWeak())
906       LValue::SetObjCNonGC(LV, !E->isOBJCGCCandidate(getContext()));
907     return LV;
908    }
909  case UnaryOperator::Real:
910  case UnaryOperator::Imag:
911    LValue LV = EmitLValue(E->getSubExpr());
912    unsigned Idx = E->getOpcode() == UnaryOperator::Imag;
913    return LValue::MakeAddr(Builder.CreateStructGEP(LV.getAddress(),
914                                                    Idx, "idx"),
915                            MakeQualifiers(ExprTy));
916  }
917}
918
919LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
920  return LValue::MakeAddr(CGM.GetAddrOfConstantStringFromLiteral(E),
921                          Qualifiers());
922}
923
924LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
925  return LValue::MakeAddr(CGM.GetAddrOfConstantStringFromObjCEncode(E),
926                          Qualifiers());
927}
928
929
930LValue CodeGenFunction::EmitPredefinedFunctionName(unsigned Type) {
931  std::string GlobalVarName;
932
933  switch (Type) {
934  default:
935    assert(0 && "Invalid type");
936  case PredefinedExpr::Func:
937    GlobalVarName = "__func__.";
938    break;
939  case PredefinedExpr::Function:
940    GlobalVarName = "__FUNCTION__.";
941    break;
942  case PredefinedExpr::PrettyFunction:
943    GlobalVarName = "__PRETTY_FUNCTION__.";
944    break;
945  }
946
947  llvm::StringRef FnName = CurFn->getName();
948  if (FnName.startswith("\01"))
949    FnName = FnName.substr(1);
950  GlobalVarName += FnName;
951
952  std::string FunctionName =
953    PredefinedExpr::ComputeName(getContext(), (PredefinedExpr::IdentType)Type,
954                                CurCodeDecl);
955
956  llvm::Constant *C =
957    CGM.GetAddrOfConstantCString(FunctionName, GlobalVarName.c_str());
958  return LValue::MakeAddr(C, Qualifiers());
959}
960
961LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
962  switch (E->getIdentType()) {
963  default:
964    return EmitUnsupportedLValue(E, "predefined expression");
965  case PredefinedExpr::Func:
966  case PredefinedExpr::Function:
967  case PredefinedExpr::PrettyFunction:
968    return EmitPredefinedFunctionName(E->getIdentType());
969  }
970}
971
972LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E) {
973  // The index must always be an integer, which is not an aggregate.  Emit it.
974  llvm::Value *Idx = EmitScalarExpr(E->getIdx());
975  QualType IdxTy  = E->getIdx()->getType();
976  bool IdxSigned = IdxTy->isSignedIntegerType();
977
978  // If the base is a vector type, then we are forming a vector element lvalue
979  // with this subscript.
980  if (E->getBase()->getType()->isVectorType()) {
981    // Emit the vector as an lvalue to get its address.
982    LValue LHS = EmitLValue(E->getBase());
983    assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
984    Idx = Builder.CreateIntCast(Idx,
985                          llvm::Type::getInt32Ty(VMContext), IdxSigned, "vidx");
986    return LValue::MakeVectorElt(LHS.getAddress(), Idx,
987                                 E->getBase()->getType().getCVRQualifiers());
988  }
989
990  // The base must be a pointer, which is not an aggregate.  Emit it.
991  llvm::Value *Base = EmitScalarExpr(E->getBase());
992
993  // Extend or truncate the index type to 32 or 64-bits.
994  unsigned IdxBitwidth = cast<llvm::IntegerType>(Idx->getType())->getBitWidth();
995  if (IdxBitwidth != LLVMPointerWidth)
996    Idx = Builder.CreateIntCast(Idx,
997                            llvm::IntegerType::get(VMContext, LLVMPointerWidth),
998                                IdxSigned, "idxprom");
999
1000  // We know that the pointer points to a type of the correct size, unless the
1001  // size is a VLA or Objective-C interface.
1002  llvm::Value *Address = 0;
1003  if (const VariableArrayType *VAT =
1004        getContext().getAsVariableArrayType(E->getType())) {
1005    llvm::Value *VLASize = GetVLASize(VAT);
1006
1007    Idx = Builder.CreateMul(Idx, VLASize);
1008
1009    QualType BaseType = getContext().getBaseElementType(VAT);
1010
1011    uint64_t BaseTypeSize = getContext().getTypeSize(BaseType) / 8;
1012    Idx = Builder.CreateUDiv(Idx,
1013                             llvm::ConstantInt::get(Idx->getType(),
1014                                                    BaseTypeSize));
1015    Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
1016  } else if (const ObjCInterfaceType *OIT =
1017             dyn_cast<ObjCInterfaceType>(E->getType())) {
1018    llvm::Value *InterfaceSize =
1019      llvm::ConstantInt::get(Idx->getType(),
1020                             getContext().getTypeSize(OIT) / 8);
1021
1022    Idx = Builder.CreateMul(Idx, InterfaceSize);
1023
1024    const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext);
1025    Address = Builder.CreateGEP(Builder.CreateBitCast(Base, i8PTy),
1026                                Idx, "arrayidx");
1027    Address = Builder.CreateBitCast(Address, Base->getType());
1028  } else {
1029    Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
1030  }
1031
1032  QualType T = E->getBase()->getType()->getPointeeType();
1033  assert(!T.isNull() &&
1034         "CodeGenFunction::EmitArraySubscriptExpr(): Illegal base type");
1035
1036  Qualifiers Quals = MakeQualifiers(T);
1037  Quals.setAddressSpace(E->getBase()->getType().getAddressSpace());
1038
1039  LValue LV = LValue::MakeAddr(Address, Quals);
1040  if (getContext().getLangOptions().ObjC1 &&
1041      getContext().getLangOptions().getGCMode() != LangOptions::NonGC) {
1042    LValue::SetObjCNonGC(LV, !E->isOBJCGCCandidate(getContext()));
1043    setObjCGCLValueClass(getContext(), E, LV);
1044  }
1045  return LV;
1046}
1047
1048static
1049llvm::Constant *GenerateConstantVector(llvm::LLVMContext &VMContext,
1050                                       llvm::SmallVector<unsigned, 4> &Elts) {
1051  llvm::SmallVector<llvm::Constant *, 4> CElts;
1052
1053  for (unsigned i = 0, e = Elts.size(); i != e; ++i)
1054    CElts.push_back(llvm::ConstantInt::get(
1055                                   llvm::Type::getInt32Ty(VMContext), Elts[i]));
1056
1057  return llvm::ConstantVector::get(&CElts[0], CElts.size());
1058}
1059
1060LValue CodeGenFunction::
1061EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
1062  // Emit the base vector as an l-value.
1063  LValue Base;
1064
1065  // ExtVectorElementExpr's base can either be a vector or pointer to vector.
1066  if (!E->isArrow()) {
1067    assert(E->getBase()->getType()->isVectorType());
1068    Base = EmitLValue(E->getBase());
1069  } else {
1070    const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
1071    llvm::Value *Ptr = EmitScalarExpr(E->getBase());
1072    Qualifiers Quals = MakeQualifiers(PT->getPointeeType());
1073    Quals.removeObjCGCAttr();
1074    Base = LValue::MakeAddr(Ptr, Quals);
1075  }
1076
1077  // Encode the element access list into a vector of unsigned indices.
1078  llvm::SmallVector<unsigned, 4> Indices;
1079  E->getEncodedElementAccess(Indices);
1080
1081  if (Base.isSimple()) {
1082    llvm::Constant *CV = GenerateConstantVector(VMContext, Indices);
1083    return LValue::MakeExtVectorElt(Base.getAddress(), CV,
1084                                    Base.getVRQualifiers());
1085  }
1086  assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
1087
1088  llvm::Constant *BaseElts = Base.getExtVectorElts();
1089  llvm::SmallVector<llvm::Constant *, 4> CElts;
1090
1091  for (unsigned i = 0, e = Indices.size(); i != e; ++i) {
1092    if (isa<llvm::ConstantAggregateZero>(BaseElts))
1093      CElts.push_back(llvm::ConstantInt::get(
1094                                         llvm::Type::getInt32Ty(VMContext), 0));
1095    else
1096      CElts.push_back(BaseElts->getOperand(Indices[i]));
1097  }
1098  llvm::Constant *CV = llvm::ConstantVector::get(&CElts[0], CElts.size());
1099  return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV,
1100                                  Base.getVRQualifiers());
1101}
1102
1103LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
1104  bool isUnion = false;
1105  bool isNonGC = false;
1106  Expr *BaseExpr = E->getBase();
1107  llvm::Value *BaseValue = NULL;
1108  Qualifiers BaseQuals;
1109
1110  // If this is s.x, emit s as an lvalue.  If it is s->x, emit s as a scalar.
1111  if (E->isArrow()) {
1112    BaseValue = EmitScalarExpr(BaseExpr);
1113    const PointerType *PTy =
1114      BaseExpr->getType()->getAs<PointerType>();
1115    if (PTy->getPointeeType()->isUnionType())
1116      isUnion = true;
1117    BaseQuals = PTy->getPointeeType().getQualifiers();
1118  } else if (isa<ObjCPropertyRefExpr>(BaseExpr->IgnoreParens()) ||
1119             isa<ObjCImplicitSetterGetterRefExpr>(
1120               BaseExpr->IgnoreParens())) {
1121    RValue RV = EmitObjCPropertyGet(BaseExpr);
1122    BaseValue = RV.getAggregateAddr();
1123    if (BaseExpr->getType()->isUnionType())
1124      isUnion = true;
1125    BaseQuals = BaseExpr->getType().getQualifiers();
1126  } else {
1127    LValue BaseLV = EmitLValue(BaseExpr);
1128    if (BaseLV.isNonGC())
1129      isNonGC = true;
1130    // FIXME: this isn't right for bitfields.
1131    BaseValue = BaseLV.getAddress();
1132    QualType BaseTy = BaseExpr->getType();
1133    if (BaseTy->isUnionType())
1134      isUnion = true;
1135    BaseQuals = BaseTy.getQualifiers();
1136  }
1137
1138  FieldDecl *Field = dyn_cast<FieldDecl>(E->getMemberDecl());
1139  // FIXME: Handle non-field member expressions
1140  assert(Field && "No code generation for non-field member references");
1141  LValue MemExpLV = EmitLValueForField(BaseValue, Field, isUnion,
1142                                       BaseQuals.getCVRQualifiers());
1143  LValue::SetObjCNonGC(MemExpLV, isNonGC);
1144  setObjCGCLValueClass(getContext(), E, MemExpLV);
1145  return MemExpLV;
1146}
1147
1148LValue CodeGenFunction::EmitLValueForBitfield(llvm::Value* BaseValue,
1149                                              FieldDecl* Field,
1150                                              unsigned CVRQualifiers) {
1151  CodeGenTypes::BitFieldInfo Info = CGM.getTypes().getBitFieldInfo(Field);
1152
1153  // FIXME: CodeGenTypes should expose a method to get the appropriate type for
1154  // FieldTy (the appropriate type is ABI-dependent).
1155  const llvm::Type *FieldTy =
1156    CGM.getTypes().ConvertTypeForMem(Field->getType());
1157  const llvm::PointerType *BaseTy =
1158  cast<llvm::PointerType>(BaseValue->getType());
1159  unsigned AS = BaseTy->getAddressSpace();
1160  BaseValue = Builder.CreateBitCast(BaseValue,
1161                                    llvm::PointerType::get(FieldTy, AS),
1162                                    "tmp");
1163
1164  llvm::Value *Idx =
1165    llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), Info.FieldNo);
1166  llvm::Value *V = Builder.CreateGEP(BaseValue, Idx, "tmp");
1167
1168  return LValue::MakeBitfield(V, Info.Start, Info.Size,
1169                              Field->getType()->isSignedIntegerType(),
1170                            Field->getType().getCVRQualifiers()|CVRQualifiers);
1171}
1172
1173LValue CodeGenFunction::EmitLValueForField(llvm::Value* BaseValue,
1174                                           FieldDecl* Field,
1175                                           bool isUnion,
1176                                           unsigned CVRQualifiers) {
1177  if (Field->isBitField())
1178    return EmitLValueForBitfield(BaseValue, Field, CVRQualifiers);
1179
1180  unsigned idx = CGM.getTypes().getLLVMFieldNo(Field);
1181  llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx, "tmp");
1182
1183  // Match union field type.
1184  if (isUnion) {
1185    const llvm::Type *FieldTy =
1186      CGM.getTypes().ConvertTypeForMem(Field->getType());
1187    const llvm::PointerType * BaseTy =
1188      cast<llvm::PointerType>(BaseValue->getType());
1189    unsigned AS = BaseTy->getAddressSpace();
1190    V = Builder.CreateBitCast(V,
1191                              llvm::PointerType::get(FieldTy, AS),
1192                              "tmp");
1193  }
1194  if (Field->getType()->isReferenceType())
1195    V = Builder.CreateLoad(V, "tmp");
1196
1197  Qualifiers Quals = MakeQualifiers(Field->getType());
1198  Quals.addCVRQualifiers(CVRQualifiers);
1199  // __weak attribute on a field is ignored.
1200  if (Quals.getObjCGCAttr() == Qualifiers::Weak)
1201    Quals.removeObjCGCAttr();
1202
1203  return LValue::MakeAddr(V, Quals);
1204}
1205
1206LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr* E){
1207  const llvm::Type *LTy = ConvertType(E->getType());
1208  llvm::Value *DeclPtr = CreateTempAlloca(LTy, ".compoundliteral");
1209
1210  const Expr* InitExpr = E->getInitializer();
1211  LValue Result = LValue::MakeAddr(DeclPtr, MakeQualifiers(E->getType()));
1212
1213  if (E->getType()->isComplexType()) {
1214    EmitComplexExprIntoAddr(InitExpr, DeclPtr, false);
1215  } else if (hasAggregateLLVMType(E->getType())) {
1216    EmitAnyExpr(InitExpr, DeclPtr, false);
1217  } else {
1218    EmitStoreThroughLValue(EmitAnyExpr(InitExpr), Result, E->getType());
1219  }
1220
1221  return Result;
1222}
1223
1224LValue
1225CodeGenFunction::EmitConditionalOperatorLValue(const ConditionalOperator* E) {
1226  if (E->isLvalue(getContext()) == Expr::LV_Valid) {
1227    llvm::BasicBlock *LHSBlock = createBasicBlock("cond.true");
1228    llvm::BasicBlock *RHSBlock = createBasicBlock("cond.false");
1229    llvm::BasicBlock *ContBlock = createBasicBlock("cond.end");
1230
1231    llvm::Value *Cond = EvaluateExprAsBool(E->getCond());
1232    Builder.CreateCondBr(Cond, LHSBlock, RHSBlock);
1233
1234    EmitBlock(LHSBlock);
1235
1236    LValue LHS = EmitLValue(E->getLHS());
1237    if (!LHS.isSimple())
1238      return EmitUnsupportedLValue(E, "conditional operator");
1239
1240    llvm::Value *Temp = CreateTempAlloca(LHS.getAddress()->getType(),
1241                                         "condtmp");
1242
1243    Builder.CreateStore(LHS.getAddress(), Temp);
1244    EmitBranch(ContBlock);
1245
1246    EmitBlock(RHSBlock);
1247    LValue RHS = EmitLValue(E->getRHS());
1248    if (!RHS.isSimple())
1249      return EmitUnsupportedLValue(E, "conditional operator");
1250
1251    Builder.CreateStore(RHS.getAddress(), Temp);
1252    EmitBranch(ContBlock);
1253
1254    EmitBlock(ContBlock);
1255
1256    Temp = Builder.CreateLoad(Temp, "lv");
1257    return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1258  }
1259
1260  // ?: here should be an aggregate.
1261  assert((hasAggregateLLVMType(E->getType()) &&
1262          !E->getType()->isAnyComplexType()) &&
1263         "Unexpected conditional operator!");
1264
1265  llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType()));
1266  EmitAggExpr(E, Temp, false);
1267
1268  return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1269}
1270
1271/// EmitCastLValue - Casts are never lvalues.  If a cast is needed by the code
1272/// generator in an lvalue context, then it must mean that we need the address
1273/// of an aggregate in order to access one of its fields.  This can happen for
1274/// all the reasons that casts are permitted with aggregate result, including
1275/// noop aggregate casts, and cast from scalar to union.
1276LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
1277  switch (E->getCastKind()) {
1278  default:
1279    // If this is an lvalue cast, treat it as a no-op.
1280    // FIXME: We shouldn't need to check for this explicitly!
1281    if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
1282      if (ICE->isLvalueCast())
1283        return EmitLValue(E->getSubExpr());
1284
1285    assert(0 && "Unhandled cast!");
1286
1287  case CastExpr::CK_NoOp:
1288  case CastExpr::CK_ConstructorConversion:
1289  case CastExpr::CK_UserDefinedConversion:
1290    return EmitLValue(E->getSubExpr());
1291
1292  case CastExpr::CK_DerivedToBase: {
1293    const RecordType *DerivedClassTy =
1294      E->getSubExpr()->getType()->getAs<RecordType>();
1295    CXXRecordDecl *DerivedClassDecl =
1296      cast<CXXRecordDecl>(DerivedClassTy->getDecl());
1297
1298    const RecordType *BaseClassTy = E->getType()->getAs<RecordType>();
1299    CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseClassTy->getDecl());
1300
1301    LValue LV = EmitLValue(E->getSubExpr());
1302
1303    // Perform the derived-to-base conversion
1304    llvm::Value *Base =
1305      GetAddressCXXOfBaseClass(LV.getAddress(), DerivedClassDecl,
1306                               BaseClassDecl, /*NullCheckValue=*/false);
1307
1308    return LValue::MakeAddr(Base, MakeQualifiers(E->getType()));
1309  }
1310
1311  case CastExpr::CK_ToUnion: {
1312    llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType()));
1313    EmitAnyExpr(E->getSubExpr(), Temp, false);
1314
1315    return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1316    }
1317  }
1318}
1319
1320LValue CodeGenFunction::EmitNullInitializationLValue(
1321                                              const CXXZeroInitValueExpr *E) {
1322  QualType Ty = E->getType();
1323  const llvm::Type *LTy = ConvertTypeForMem(Ty);
1324  llvm::AllocaInst *Alloc = CreateTempAlloca(LTy);
1325  unsigned Align = getContext().getTypeAlign(Ty)/8;
1326  Alloc->setAlignment(Align);
1327  LValue lvalue = LValue::MakeAddr(Alloc, Qualifiers());
1328  EmitMemSetToZero(lvalue.getAddress(), Ty);
1329  return lvalue;
1330}
1331
1332//===--------------------------------------------------------------------===//
1333//                             Expression Emission
1334//===--------------------------------------------------------------------===//
1335
1336
1337RValue CodeGenFunction::EmitCallExpr(const CallExpr *E) {
1338  // Builtins never have block type.
1339  if (E->getCallee()->getType()->isBlockPointerType())
1340    return EmitBlockCallExpr(E);
1341
1342  if (const CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(E))
1343    return EmitCXXMemberCallExpr(CE);
1344
1345  const Decl *TargetDecl = 0;
1346  if (const ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E->getCallee())) {
1347    if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CE->getSubExpr())) {
1348      TargetDecl = DRE->getDecl();
1349      if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(TargetDecl))
1350        if (unsigned builtinID = FD->getBuiltinID())
1351          return EmitBuiltinExpr(FD, builtinID, E);
1352    }
1353  }
1354
1355  if (const CXXOperatorCallExpr *CE = dyn_cast<CXXOperatorCallExpr>(E))
1356    if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(TargetDecl))
1357      return EmitCXXOperatorMemberCallExpr(CE, MD);
1358
1359  if (isa<CXXPseudoDestructorExpr>(E->getCallee())) {
1360    // C++ [expr.pseudo]p1:
1361    //   The result shall only be used as the operand for the function call
1362    //   operator (), and the result of such a call has type void. The only
1363    //   effect is the evaluation of the postfix-expression before the dot or
1364    //   arrow.
1365    EmitScalarExpr(E->getCallee());
1366    return RValue::get(0);
1367  }
1368
1369  llvm::Value *Callee = EmitScalarExpr(E->getCallee());
1370  return EmitCall(Callee, E->getCallee()->getType(),
1371                  E->arg_begin(), E->arg_end(), TargetDecl);
1372}
1373
1374LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
1375  // Comma expressions just emit their LHS then their RHS as an l-value.
1376  if (E->getOpcode() == BinaryOperator::Comma) {
1377    EmitAnyExpr(E->getLHS());
1378    return EmitLValue(E->getRHS());
1379  }
1380
1381  if (E->getOpcode() == BinaryOperator::PtrMemD ||
1382      E->getOpcode() == BinaryOperator::PtrMemI)
1383    return EmitPointerToDataMemberBinaryExpr(E);
1384
1385  // Can only get l-value for binary operator expressions which are a
1386  // simple assignment of aggregate type.
1387  if (E->getOpcode() != BinaryOperator::Assign)
1388    return EmitUnsupportedLValue(E, "binary l-value expression");
1389
1390  if (!hasAggregateLLVMType(E->getType())) {
1391    // Emit the LHS as an l-value.
1392    LValue LV = EmitLValue(E->getLHS());
1393
1394    llvm::Value *RHS = EmitScalarExpr(E->getRHS());
1395    EmitStoreOfScalar(RHS, LV.getAddress(), LV.isVolatileQualified(),
1396                      E->getType());
1397    return LV;
1398  }
1399
1400  llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType()));
1401  EmitAggExpr(E, Temp, false);
1402  // FIXME: Are these qualifiers correct?
1403  return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1404}
1405
1406LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
1407  RValue RV = EmitCallExpr(E);
1408
1409  if (RV.isScalar()) {
1410    assert(E->getCallReturnType()->isReferenceType() &&
1411           "Can't have a scalar return unless the return type is a "
1412           "reference type!");
1413
1414    return LValue::MakeAddr(RV.getScalarVal(), MakeQualifiers(E->getType()));
1415  }
1416
1417  return LValue::MakeAddr(RV.getAggregateAddr(), MakeQualifiers(E->getType()));
1418}
1419
1420LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
1421  // FIXME: This shouldn't require another copy.
1422  llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType()));
1423  EmitAggExpr(E, Temp, false);
1424  return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1425}
1426
1427LValue
1428CodeGenFunction::EmitCXXConditionDeclLValue(const CXXConditionDeclExpr *E) {
1429  EmitLocalBlockVarDecl(*E->getVarDecl());
1430  return EmitDeclRefLValue(E);
1431}
1432
1433LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
1434  llvm::Value *Temp = CreateTempAlloca(ConvertTypeForMem(E->getType()), "tmp");
1435  EmitCXXConstructExpr(Temp, E);
1436  return LValue::MakeAddr(Temp, MakeQualifiers(E->getType()));
1437}
1438
1439LValue
1440CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
1441  LValue LV = EmitLValue(E->getSubExpr());
1442
1443  PushCXXTemporary(E->getTemporary(), LV.getAddress());
1444
1445  return LV;
1446}
1447
1448LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
1449  // Can only get l-value for message expression returning aggregate type
1450  RValue RV = EmitObjCMessageExpr(E);
1451  // FIXME: can this be volatile?
1452  return LValue::MakeAddr(RV.getAggregateAddr(), MakeQualifiers(E->getType()));
1453}
1454
1455llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
1456                                             const ObjCIvarDecl *Ivar) {
1457  return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
1458}
1459
1460LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
1461                                          llvm::Value *BaseValue,
1462                                          const ObjCIvarDecl *Ivar,
1463                                          unsigned CVRQualifiers) {
1464  return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
1465                                                   Ivar, CVRQualifiers);
1466}
1467
1468LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
1469  // FIXME: A lot of the code below could be shared with EmitMemberExpr.
1470  llvm::Value *BaseValue = 0;
1471  const Expr *BaseExpr = E->getBase();
1472  Qualifiers BaseQuals;
1473  QualType ObjectTy;
1474  if (E->isArrow()) {
1475    BaseValue = EmitScalarExpr(BaseExpr);
1476    ObjectTy = BaseExpr->getType()->getPointeeType();
1477    BaseQuals = ObjectTy.getQualifiers();
1478  } else {
1479    LValue BaseLV = EmitLValue(BaseExpr);
1480    // FIXME: this isn't right for bitfields.
1481    BaseValue = BaseLV.getAddress();
1482    ObjectTy = BaseExpr->getType();
1483    BaseQuals = ObjectTy.getQualifiers();
1484  }
1485
1486  LValue LV =
1487    EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
1488                      BaseQuals.getCVRQualifiers());
1489  setObjCGCLValueClass(getContext(), E, LV);
1490  return LV;
1491}
1492
1493LValue
1494CodeGenFunction::EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E) {
1495  // This is a special l-value that just issues sends when we load or store
1496  // through it.
1497  return LValue::MakePropertyRef(E, E->getType().getCVRQualifiers());
1498}
1499
1500LValue
1501CodeGenFunction::EmitObjCKVCRefLValue(
1502                                const ObjCImplicitSetterGetterRefExpr *E) {
1503  // This is a special l-value that just issues sends when we load or store
1504  // through it.
1505  return LValue::MakeKVCRef(E, E->getType().getCVRQualifiers());
1506}
1507
1508LValue
1509CodeGenFunction::EmitObjCSuperExprLValue(const ObjCSuperExpr *E) {
1510  return EmitUnsupportedLValue(E, "use of super");
1511}
1512
1513LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
1514
1515  // Can only get l-value for message expression returning aggregate type
1516  RValue RV = EmitAnyExprToTemp(E);
1517  // FIXME: can this be volatile?
1518  return LValue::MakeAddr(RV.getAggregateAddr(), MakeQualifiers(E->getType()));
1519}
1520
1521
1522LValue CodeGenFunction::EmitPointerToDataMemberLValue(const DeclRefExpr *E) {
1523  const FieldDecl *Field = cast<FieldDecl>(E->getDecl());
1524  const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Field->getDeclContext());
1525  QualType NNSpecTy =
1526    getContext().getCanonicalType(
1527      getContext().getTypeDeclType(const_cast<CXXRecordDecl*>(ClassDecl)));
1528  NNSpecTy = getContext().getPointerType(NNSpecTy);
1529  llvm::Value *V = llvm::Constant::getNullValue(ConvertType(NNSpecTy));
1530  LValue MemExpLV = EmitLValueForField(V, const_cast<FieldDecl*>(Field),
1531                                       /*isUnion*/false, /*Qualifiers*/0);
1532  const llvm::Type* ResultType = ConvertType(
1533                                             getContext().getPointerDiffType());
1534  V = Builder.CreatePtrToInt(MemExpLV.getAddress(), ResultType,
1535                             "datamember");
1536  LValue LV = LValue::MakeAddr(V, MakeQualifiers(E->getType()));
1537  return LV;
1538}
1539
1540RValue CodeGenFunction::EmitCall(llvm::Value *Callee, QualType CalleeType,
1541                                 CallExpr::const_arg_iterator ArgBeg,
1542                                 CallExpr::const_arg_iterator ArgEnd,
1543                                 const Decl *TargetDecl) {
1544  // Get the actual function type. The callee type will always be a pointer to
1545  // function type or a block pointer type.
1546  assert(CalleeType->isFunctionPointerType() &&
1547         "Call must have function pointer type!");
1548
1549  CalleeType = getContext().getCanonicalType(CalleeType);
1550
1551  QualType FnType = cast<PointerType>(CalleeType)->getPointeeType();
1552  QualType ResultType = cast<FunctionType>(FnType)->getResultType();
1553
1554  CallArgList Args;
1555  EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), ArgBeg, ArgEnd);
1556
1557  // FIXME: We should not need to do this, it should be part of the function
1558  // type.
1559  unsigned CallingConvention = 0;
1560  if (const llvm::Function *F =
1561      dyn_cast<llvm::Function>(Callee->stripPointerCasts()))
1562    CallingConvention = F->getCallingConv();
1563  return EmitCall(CGM.getTypes().getFunctionInfo(ResultType, Args,
1564                                                 CallingConvention),
1565                  Callee, Args, TargetDecl);
1566}
1567
1568LValue CodeGenFunction::EmitPointerToDataMemberBinaryExpr(
1569                                                    const BinaryOperator *E) {
1570  llvm::Value *BaseV = EmitLValue(E->getLHS()).getAddress();
1571  if (E->getOpcode() == BinaryOperator::PtrMemI)
1572    BaseV = Builder.CreateLoad(BaseV, "indir.ptr");
1573  const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(getLLVMContext());
1574  BaseV = Builder.CreateBitCast(BaseV, i8Ty);
1575  LValue RHSLV = EmitLValue(E->getRHS());
1576  llvm::Value *OffsetV =
1577    EmitLoadOfLValue(RHSLV, E->getRHS()->getType()).getScalarVal();
1578  const llvm::Type* ResultType = ConvertType(getContext().getPointerDiffType());
1579  OffsetV = Builder.CreateBitCast(OffsetV, ResultType);
1580  llvm::Value *AddV = Builder.CreateInBoundsGEP(BaseV, OffsetV, "add.ptr");
1581  QualType Ty = E->getRHS()->getType();
1582  const MemberPointerType *MemPtrType = Ty->getAs<MemberPointerType>();
1583  Ty = MemPtrType->getPointeeType();
1584  const llvm::Type* PType =
1585  ConvertType(getContext().getPointerType(Ty));
1586  AddV = Builder.CreateBitCast(AddV, PType);
1587  LValue LV = LValue::MakeAddr(AddV, MakeQualifiers(Ty));
1588  return LV;
1589}
1590
1591