CGExpr.cpp revision 3e41d60eb627dc227c770f1c1c87d06909cf05fd 
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 char *Name) {
32  return new llvm::AllocaInst(Ty, 0, Name, AllocaInsertPt);
33}
34
35/// EvaluateExprAsBool - Perform the usual unary conversions on the specified
36/// expression and compare the result against zero, returning an Int1Ty value.
37llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
38  QualType BoolTy = getContext().BoolTy;
39  if (!E->getType()->isAnyComplexType())
40    return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy);
41
42  return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(),BoolTy);
43}
44
45/// EmitAnyExpr - Emit code to compute the specified expression which can have
46/// any type.  The result is returned as an RValue struct.  If this is an
47/// aggregate expression, the aggloc/agglocvolatile arguments indicate where
48/// the result should be returned.
49RValue CodeGenFunction::EmitAnyExpr(const Expr *E, llvm::Value *AggLoc,
50                                    bool isAggLocVolatile) {
51  if (!hasAggregateLLVMType(E->getType()))
52    return RValue::get(EmitScalarExpr(E));
53  else if (E->getType()->isAnyComplexType())
54    return RValue::getComplex(EmitComplexExpr(E));
55
56  EmitAggExpr(E, AggLoc, isAggLocVolatile);
57  return RValue::getAggregate(AggLoc);
58}
59
60/// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result
61/// will always be accessible even if no aggregate location is
62/// provided.
63RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E, llvm::Value *AggLoc,
64                                          bool isAggLocVolatile) {
65  if (!AggLoc && hasAggregateLLVMType(E->getType()) &&
66      !E->getType()->isAnyComplexType())
67    AggLoc = CreateTempAlloca(ConvertType(E->getType()), "agg.tmp");
68  return EmitAnyExpr(E, AggLoc, isAggLocVolatile);
69}
70
71/// getAccessedFieldNo - Given an encoded value and a result number, return
72/// the input field number being accessed.
73unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
74                                             const llvm::Constant *Elts) {
75  if (isa<llvm::ConstantAggregateZero>(Elts))
76    return 0;
77
78  return cast<llvm::ConstantInt>(Elts->getOperand(Idx))->getZExtValue();
79}
80
81
82//===----------------------------------------------------------------------===//
83//                         LValue Expression Emission
84//===----------------------------------------------------------------------===//
85
86RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
87  if (Ty->isVoidType()) {
88    return RValue::get(0);
89  } else if (const ComplexType *CTy = Ty->getAsComplexType()) {
90    const llvm::Type *EltTy = ConvertType(CTy->getElementType());
91    llvm::Value *U = llvm::UndefValue::get(EltTy);
92    return RValue::getComplex(std::make_pair(U, U));
93  } else if (hasAggregateLLVMType(Ty)) {
94    const llvm::Type *LTy = llvm::PointerType::getUnqual(ConvertType(Ty));
95    return RValue::getAggregate(llvm::UndefValue::get(LTy));
96  } else {
97    return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
98  }
99}
100
101RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
102                                              const char *Name) {
103  ErrorUnsupported(E, Name);
104  return GetUndefRValue(E->getType());
105}
106
107LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
108                                              const char *Name) {
109  ErrorUnsupported(E, Name);
110  llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
111  return LValue::MakeAddr(llvm::UndefValue::get(Ty),
112                          E->getType().getCVRQualifiers());
113}
114
115/// EmitLValue - Emit code to compute a designator that specifies the location
116/// of the expression.
117///
118/// This can return one of two things: a simple address or a bitfield
119/// reference.  In either case, the LLVM Value* in the LValue structure is
120/// guaranteed to be an LLVM pointer type.
121///
122/// If this returns a bitfield reference, nothing about the pointee type of
123/// the LLVM value is known: For example, it may not be a pointer to an
124/// integer.
125///
126/// If this returns a normal address, and if the lvalue's C type is fixed
127/// size, this method guarantees that the returned pointer type will point to
128/// an LLVM type of the same size of the lvalue's type.  If the lvalue has a
129/// variable length type, this is not possible.
130///
131LValue CodeGenFunction::EmitLValue(const Expr *E) {
132  switch (E->getStmtClass()) {
133  default: return EmitUnsupportedLValue(E, "l-value expression");
134
135  case Expr::BinaryOperatorClass:
136    return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
137  case Expr::CallExprClass:
138  case Expr::CXXOperatorCallExprClass:
139    return EmitCallExprLValue(cast<CallExpr>(E));
140  case Expr::VAArgExprClass:
141    return EmitVAArgExprLValue(cast<VAArgExpr>(E));
142  case Expr::DeclRefExprClass:
143  case Expr::QualifiedDeclRefExprClass:
144    return EmitDeclRefLValue(cast<DeclRefExpr>(E));
145  case Expr::ParenExprClass:return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
146  case Expr::PredefinedExprClass:
147    return EmitPredefinedLValue(cast<PredefinedExpr>(E));
148  case Expr::StringLiteralClass:
149    return EmitStringLiteralLValue(cast<StringLiteral>(E));
150
151  case Expr::CXXConditionDeclExprClass:
152    return EmitCXXConditionDeclLValue(cast<CXXConditionDeclExpr>(E));
153
154  case Expr::ObjCMessageExprClass:
155    return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
156  case Expr::ObjCIvarRefExprClass:
157    return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
158  case Expr::ObjCPropertyRefExprClass:
159    return EmitObjCPropertyRefLValue(cast<ObjCPropertyRefExpr>(E));
160  case Expr::ObjCKVCRefExprClass:
161    return EmitObjCKVCRefLValue(cast<ObjCKVCRefExpr>(E));
162  case Expr::ObjCSuperExprClass:
163    return EmitObjCSuperExpr(cast<ObjCSuperExpr>(E));
164
165  case Expr::UnaryOperatorClass:
166    return EmitUnaryOpLValue(cast<UnaryOperator>(E));
167  case Expr::ArraySubscriptExprClass:
168    return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
169  case Expr::ExtVectorElementExprClass:
170    return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
171  case Expr::MemberExprClass: return EmitMemberExpr(cast<MemberExpr>(E));
172  case Expr::CompoundLiteralExprClass:
173    return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
174  case Expr::ChooseExprClass:
175    // __builtin_choose_expr is the lvalue of the selected operand.
176    if (cast<ChooseExpr>(E)->isConditionTrue(getContext()))
177      return EmitLValue(cast<ChooseExpr>(E)->getLHS());
178    else
179      return EmitLValue(cast<ChooseExpr>(E)->getRHS());
180  }
181}
182
183llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile,
184                                               QualType Ty) {
185  llvm::Value *V = Builder.CreateLoad(Addr, Volatile, "tmp");
186
187  // Bool can have different representation in memory than in
188  // registers.
189  if (Ty->isBooleanType())
190    if (V->getType() != llvm::Type::Int1Ty)
191      V = Builder.CreateTrunc(V, llvm::Type::Int1Ty, "tobool");
192
193  return V;
194}
195
196void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr,
197                                        bool Volatile) {
198  // Handle stores of types which have different representations in
199  // memory and as LLVM values.
200
201  // FIXME: We shouldn't be this loose, we should only do this
202  // conversion when we have a type we know has a different memory
203  // representation (e.g., bool).
204
205  const llvm::Type *SrcTy = Value->getType();
206  const llvm::PointerType *DstPtr = cast<llvm::PointerType>(Addr->getType());
207  if (DstPtr->getElementType() != SrcTy) {
208    const llvm::Type *MemTy =
209      llvm::PointerType::get(SrcTy, DstPtr->getAddressSpace());
210    Addr = Builder.CreateBitCast(Addr, MemTy, "storetmp");
211  }
212
213  Builder.CreateStore(Value, Addr, Volatile);
214}
215
216/// EmitLoadOfLValue - Given an expression that represents a value lvalue,
217/// this method emits the address of the lvalue, then loads the result as an
218/// rvalue, returning the rvalue.
219RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, QualType ExprType) {
220  if (LV.isObjCWeak()) {
221    // load of a __weak object.
222    llvm::Value *AddrWeakObj = LV.getAddress();
223    llvm::Value *read_weak = CGM.getObjCRuntime().EmitObjCWeakRead(*this,
224                                                                   AddrWeakObj);
225    return RValue::get(read_weak);
226  }
227
228  if (LV.isSimple()) {
229    llvm::Value *Ptr = LV.getAddress();
230    const llvm::Type *EltTy =
231      cast<llvm::PointerType>(Ptr->getType())->getElementType();
232
233    // Simple scalar l-value.
234    if (EltTy->isSingleValueType())
235      return RValue::get(EmitLoadOfScalar(Ptr, LV.isVolatileQualified(),
236                                          ExprType));
237
238    assert(ExprType->isFunctionType() && "Unknown scalar value");
239    return RValue::get(Ptr);
240  }
241
242  if (LV.isVectorElt()) {
243    llvm::Value *Vec = Builder.CreateLoad(LV.getVectorAddr(),
244                                          LV.isVolatileQualified(), "tmp");
245    return RValue::get(Builder.CreateExtractElement(Vec, LV.getVectorIdx(),
246                                                    "vecext"));
247  }
248
249  // If this is a reference to a subset of the elements of a vector, either
250  // shuffle the input or extract/insert them as appropriate.
251  if (LV.isExtVectorElt())
252    return EmitLoadOfExtVectorElementLValue(LV, ExprType);
253
254  if (LV.isBitfield())
255    return EmitLoadOfBitfieldLValue(LV, ExprType);
256
257  if (LV.isPropertyRef())
258    return EmitLoadOfPropertyRefLValue(LV, ExprType);
259
260  if (LV.isKVCRef())
261    return EmitLoadOfKVCRefLValue(LV, ExprType);
262
263  assert(0 && "Unknown LValue type!");
264  //an invalid RValue, but the assert will
265  //ensure that this point is never reached
266  return RValue();
267}
268
269RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
270                                                 QualType ExprType) {
271  unsigned StartBit = LV.getBitfieldStartBit();
272  unsigned BitfieldSize = LV.getBitfieldSize();
273  llvm::Value *Ptr = LV.getBitfieldAddr();
274
275  const llvm::Type *EltTy =
276    cast<llvm::PointerType>(Ptr->getType())->getElementType();
277  unsigned EltTySize = CGM.getTargetData().getTypeSizeInBits(EltTy);
278
279  // In some cases the bitfield may straddle two memory locations.
280  // Currently we load the entire bitfield, then do the magic to
281  // sign-extend it if necessary. This results in somewhat more code
282  // than necessary for the common case (one load), since two shifts
283  // accomplish both the masking and sign extension.
284  unsigned LowBits = std::min(BitfieldSize, EltTySize - StartBit);
285  llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "tmp");
286
287  // Shift to proper location.
288  if (StartBit)
289    Val = Builder.CreateLShr(Val, llvm::ConstantInt::get(EltTy, StartBit),
290                             "bf.lo");
291
292  // Mask off unused bits.
293  llvm::Constant *LowMask =
294    llvm::ConstantInt::get(llvm::APInt::getLowBitsSet(EltTySize, LowBits));
295  Val = Builder.CreateAnd(Val, LowMask, "bf.lo.cleared");
296
297  // Fetch the high bits if necessary.
298  if (LowBits < BitfieldSize) {
299    unsigned HighBits = BitfieldSize - LowBits;
300    llvm::Value *HighPtr =
301      Builder.CreateGEP(Ptr, llvm::ConstantInt::get(llvm::Type::Int32Ty, 1),
302                        "bf.ptr.hi");
303    llvm::Value *HighVal = Builder.CreateLoad(HighPtr,
304                                              LV.isVolatileQualified(),
305                                              "tmp");
306
307    // Mask off unused bits.
308    llvm::Constant *HighMask =
309      llvm::ConstantInt::get(llvm::APInt::getLowBitsSet(EltTySize, HighBits));
310    HighVal = Builder.CreateAnd(HighVal, HighMask, "bf.lo.cleared");
311
312    // Shift to proper location and or in to bitfield value.
313    HighVal = Builder.CreateShl(HighVal,
314                                llvm::ConstantInt::get(EltTy, LowBits));
315    Val = Builder.CreateOr(Val, HighVal, "bf.val");
316  }
317
318  // Sign extend if necessary.
319  if (LV.isBitfieldSigned()) {
320    llvm::Value *ExtraBits = llvm::ConstantInt::get(EltTy,
321                                                    EltTySize - BitfieldSize);
322    Val = Builder.CreateAShr(Builder.CreateShl(Val, ExtraBits),
323                             ExtraBits, "bf.val.sext");
324  }
325
326  // The bitfield type and the normal type differ when the storage sizes
327  // differ (currently just _Bool).
328  Val = Builder.CreateIntCast(Val, ConvertType(ExprType), false, "tmp");
329
330  return RValue::get(Val);
331}
332
333RValue CodeGenFunction::EmitLoadOfPropertyRefLValue(LValue LV,
334                                                    QualType ExprType) {
335  return EmitObjCPropertyGet(LV.getPropertyRefExpr());
336}
337
338RValue CodeGenFunction::EmitLoadOfKVCRefLValue(LValue LV,
339                                               QualType ExprType) {
340  return EmitObjCPropertyGet(LV.getKVCRefExpr());
341}
342
343// If this is a reference to a subset of the elements of a vector, create an
344// appropriate shufflevector.
345RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV,
346                                                         QualType ExprType) {
347  llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddr(),
348                                        LV.isVolatileQualified(), "tmp");
349
350  const llvm::Constant *Elts = LV.getExtVectorElts();
351
352  // If the result of the expression is a non-vector type, we must be
353  // extracting a single element.  Just codegen as an extractelement.
354  const VectorType *ExprVT = ExprType->getAsVectorType();
355  if (!ExprVT) {
356    unsigned InIdx = getAccessedFieldNo(0, Elts);
357    llvm::Value *Elt = llvm::ConstantInt::get(llvm::Type::Int32Ty, InIdx);
358    return RValue::get(Builder.CreateExtractElement(Vec, Elt, "tmp"));
359  }
360
361  // Always use shuffle vector to try to retain the original program structure
362  unsigned NumResultElts = ExprVT->getNumElements();
363
364  llvm::SmallVector<llvm::Constant*, 4> Mask;
365  for (unsigned i = 0; i != NumResultElts; ++i) {
366    unsigned InIdx = getAccessedFieldNo(i, Elts);
367    Mask.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, InIdx));
368  }
369
370  llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
371  Vec = Builder.CreateShuffleVector(Vec,
372                                    llvm::UndefValue::get(Vec->getType()),
373                                    MaskV, "tmp");
374  return RValue::get(Vec);
375}
376
377
378
379/// EmitStoreThroughLValue - Store the specified rvalue into the specified
380/// lvalue, where both are guaranteed to the have the same type, and that type
381/// is 'Ty'.
382void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
383                                             QualType Ty) {
384  if (!Dst.isSimple()) {
385    if (Dst.isVectorElt()) {
386      // Read/modify/write the vector, inserting the new element.
387      llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddr(),
388                                            Dst.isVolatileQualified(), "tmp");
389      Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
390                                        Dst.getVectorIdx(), "vecins");
391      Builder.CreateStore(Vec, Dst.getVectorAddr(),Dst.isVolatileQualified());
392      return;
393    }
394
395    // If this is an update of extended vector elements, insert them as
396    // appropriate.
397    if (Dst.isExtVectorElt())
398      return EmitStoreThroughExtVectorComponentLValue(Src, Dst, Ty);
399
400    if (Dst.isBitfield())
401      return EmitStoreThroughBitfieldLValue(Src, Dst, Ty);
402
403    if (Dst.isPropertyRef())
404      return EmitStoreThroughPropertyRefLValue(Src, Dst, Ty);
405
406    if (Dst.isKVCRef())
407      return EmitStoreThroughKVCRefLValue(Src, Dst, Ty);
408
409    assert(0 && "Unknown LValue type");
410  }
411
412  if (Dst.isObjCWeak()) {
413    // load of a __weak object.
414    llvm::Value *LvalueDst = Dst.getAddress();
415    llvm::Value *src = Src.getScalarVal();
416    CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
417    return;
418  }
419
420  if (Dst.isObjCStrong()) {
421    // load of a __strong object.
422    llvm::Value *LvalueDst = Dst.getAddress();
423    llvm::Value *src = Src.getScalarVal();
424    if (Dst.isObjCIvar())
425      CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, LvalueDst);
426    else
427      CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst);
428    return;
429  }
430
431  assert(Src.isScalar() && "Can't emit an agg store with this method");
432  EmitStoreOfScalar(Src.getScalarVal(), Dst.getAddress(),
433                    Dst.isVolatileQualified());
434}
435
436void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
437                                                     QualType Ty,
438                                                     llvm::Value **Result) {
439  unsigned StartBit = Dst.getBitfieldStartBit();
440  unsigned BitfieldSize = Dst.getBitfieldSize();
441  llvm::Value *Ptr = Dst.getBitfieldAddr();
442
443  const llvm::Type *EltTy =
444    cast<llvm::PointerType>(Ptr->getType())->getElementType();
445  unsigned EltTySize = CGM.getTargetData().getTypeSizeInBits(EltTy);
446
447  // Get the new value, cast to the appropriate type and masked to
448  // exactly the size of the bit-field.
449  llvm::Value *SrcVal = Src.getScalarVal();
450  llvm::Value *NewVal = Builder.CreateIntCast(SrcVal, EltTy, false, "tmp");
451  llvm::Constant *Mask =
452    llvm::ConstantInt::get(llvm::APInt::getLowBitsSet(EltTySize, BitfieldSize));
453  NewVal = Builder.CreateAnd(NewVal, Mask, "bf.value");
454
455  // Return the new value of the bit-field, if requested.
456  if (Result) {
457    // Cast back to the proper type for result.
458    const llvm::Type *SrcTy = SrcVal->getType();
459    llvm::Value *SrcTrunc = Builder.CreateIntCast(NewVal, SrcTy, false,
460                                                  "bf.reload.val");
461
462    // Sign extend if necessary.
463    if (Dst.isBitfieldSigned()) {
464      unsigned SrcTySize = CGM.getTargetData().getTypeSizeInBits(SrcTy);
465      llvm::Value *ExtraBits = llvm::ConstantInt::get(SrcTy,
466                                                      SrcTySize - BitfieldSize);
467      SrcTrunc = Builder.CreateAShr(Builder.CreateShl(SrcTrunc, ExtraBits),
468                                    ExtraBits, "bf.reload.sext");
469    }
470
471    *Result = SrcTrunc;
472  }
473
474  // In some cases the bitfield may straddle two memory locations.
475  // Emit the low part first and check to see if the high needs to be
476  // done.
477  unsigned LowBits = std::min(BitfieldSize, EltTySize - StartBit);
478  llvm::Value *LowVal = Builder.CreateLoad(Ptr, Dst.isVolatileQualified(),
479                                           "bf.prev.low");
480
481  // Compute the mask for zero-ing the low part of this bitfield.
482  llvm::Constant *InvMask =
483    llvm::ConstantInt::get(~llvm::APInt::getBitsSet(EltTySize, StartBit,
484                                                    StartBit + LowBits));
485
486  // Compute the new low part as
487  //   LowVal = (LowVal & InvMask) | (NewVal << StartBit),
488  // with the shift of NewVal implicitly stripping the high bits.
489  llvm::Value *NewLowVal =
490    Builder.CreateShl(NewVal, llvm::ConstantInt::get(EltTy, StartBit),
491                      "bf.value.lo");
492  LowVal = Builder.CreateAnd(LowVal, InvMask, "bf.prev.lo.cleared");
493  LowVal = Builder.CreateOr(LowVal, NewLowVal, "bf.new.lo");
494
495  // Write back.
496  Builder.CreateStore(LowVal, Ptr, Dst.isVolatileQualified());
497
498  // If the low part doesn't cover the bitfield emit a high part.
499  if (LowBits < BitfieldSize) {
500    unsigned HighBits = BitfieldSize - LowBits;
501    llvm::Value *HighPtr =
502      Builder.CreateGEP(Ptr, llvm::ConstantInt::get(llvm::Type::Int32Ty, 1),
503                        "bf.ptr.hi");
504    llvm::Value *HighVal = Builder.CreateLoad(HighPtr,
505                                              Dst.isVolatileQualified(),
506                                              "bf.prev.hi");
507
508    // Compute the mask for zero-ing the high part of this bitfield.
509    llvm::Constant *InvMask =
510      llvm::ConstantInt::get(~llvm::APInt::getLowBitsSet(EltTySize, HighBits));
511
512    // Compute the new high part as
513    //   HighVal = (HighVal & InvMask) | (NewVal lshr LowBits),
514    // where the high bits of NewVal have already been cleared and the
515    // shift stripping the low bits.
516    llvm::Value *NewHighVal =
517      Builder.CreateLShr(NewVal, llvm::ConstantInt::get(EltTy, LowBits),
518                        "bf.value.high");
519    HighVal = Builder.CreateAnd(HighVal, InvMask, "bf.prev.hi.cleared");
520    HighVal = Builder.CreateOr(HighVal, NewHighVal, "bf.new.hi");
521
522    // Write back.
523    Builder.CreateStore(HighVal, HighPtr, Dst.isVolatileQualified());
524  }
525}
526
527void CodeGenFunction::EmitStoreThroughPropertyRefLValue(RValue Src,
528                                                        LValue Dst,
529                                                        QualType Ty) {
530  EmitObjCPropertySet(Dst.getPropertyRefExpr(), Src);
531}
532
533void CodeGenFunction::EmitStoreThroughKVCRefLValue(RValue Src,
534                                                   LValue Dst,
535                                                   QualType Ty) {
536  EmitObjCPropertySet(Dst.getKVCRefExpr(), Src);
537}
538
539void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
540                                                               LValue Dst,
541                                                               QualType Ty) {
542  // This access turns into a read/modify/write of the vector.  Load the input
543  // value now.
544  llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddr(),
545                                        Dst.isVolatileQualified(), "tmp");
546  const llvm::Constant *Elts = Dst.getExtVectorElts();
547
548  llvm::Value *SrcVal = Src.getScalarVal();
549
550  if (const VectorType *VTy = Ty->getAsVectorType()) {
551    unsigned NumSrcElts = VTy->getNumElements();
552    unsigned NumDstElts =
553       cast<llvm::VectorType>(Vec->getType())->getNumElements();
554    if (NumDstElts == NumSrcElts) {
555      // Use shuffle vector is the src and destination are the same number
556      // of elements
557      llvm::SmallVector<llvm::Constant*, 4> Mask;
558      for (unsigned i = 0; i != NumSrcElts; ++i) {
559        unsigned InIdx = getAccessedFieldNo(i, Elts);
560        Mask.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, InIdx));
561      }
562
563      llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
564      Vec = Builder.CreateShuffleVector(SrcVal,
565                                        llvm::UndefValue::get(Vec->getType()),
566                                        MaskV, "tmp");
567    }
568    else if (NumDstElts > NumSrcElts) {
569      // Extended the source vector to the same length and then shuffle it
570      // into the destination.
571      // FIXME: since we're shuffling with undef, can we just use the indices
572      //        into that?  This could be simpler.
573      llvm::SmallVector<llvm::Constant*, 4> ExtMask;
574      unsigned i;
575      for (i = 0; i != NumSrcElts; ++i)
576        ExtMask.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, i));
577      for (; i != NumDstElts; ++i)
578        ExtMask.push_back(llvm::UndefValue::get(llvm::Type::Int32Ty));
579      llvm::Value *ExtMaskV = llvm::ConstantVector::get(&ExtMask[0],
580                                                        ExtMask.size());
581      llvm::Value *ExtSrcVal = Builder.CreateShuffleVector(SrcVal,
582                                        llvm::UndefValue::get(SrcVal->getType()),
583                                        ExtMaskV, "tmp");
584      // build identity
585      llvm::SmallVector<llvm::Constant*, 4> Mask;
586      for (unsigned i = 0; i != NumDstElts; ++i) {
587        Mask.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, i));
588      }
589      // modify when what gets shuffled in
590      for (unsigned i = 0; i != NumSrcElts; ++i) {
591        unsigned Idx = getAccessedFieldNo(i, Elts);
592        Mask[Idx] =llvm::ConstantInt::get(llvm::Type::Int32Ty, i+NumDstElts);
593      }
594      llvm::Value *MaskV = llvm::ConstantVector::get(&Mask[0], Mask.size());
595      Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV, "tmp");
596    }
597    else {
598      // We should never shorten the vector
599      assert(0 && "unexpected shorten vector length");
600    }
601  } else {
602    // If the Src is a scalar (not a vector) it must be updating one element.
603    unsigned InIdx = getAccessedFieldNo(0, Elts);
604    llvm::Value *Elt = llvm::ConstantInt::get(llvm::Type::Int32Ty, InIdx);
605    Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt, "tmp");
606  }
607
608  Builder.CreateStore(Vec, Dst.getExtVectorAddr(), Dst.isVolatileQualified());
609}
610
611/// SetVarDeclObjCAttribute - Set __weak/__strong attributes into the LValue
612/// object.
613static void SetVarDeclObjCAttribute(ASTContext &Ctx, const Decl *VD,
614                                    const QualType &Ty, LValue &LV)
615{
616  if (const ObjCGCAttr *A = VD->getAttr<ObjCGCAttr>()) {
617    ObjCGCAttr::GCAttrTypes attrType = A->getType();
618    LValue::SetObjCType(attrType == ObjCGCAttr::Weak,
619                        attrType == ObjCGCAttr::Strong, LV);
620  }
621  else if (Ctx.getLangOptions().ObjC1 &&
622           Ctx.getLangOptions().getGCMode() != LangOptions::NonGC) {
623    // Default behavious under objective-c's gc is for objective-c pointers
624    // be treated as though they were declared as __strong.
625    if (Ctx.isObjCObjectPointerType(Ty))
626      LValue::SetObjCType(false, true, LV);
627  }
628}
629
630LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
631  const VarDecl *VD = dyn_cast<VarDecl>(E->getDecl());
632
633  if (VD && (VD->isBlockVarDecl() || isa<ParmVarDecl>(VD) ||
634        isa<ImplicitParamDecl>(VD))) {
635    LValue LV;
636    if (VD->getStorageClass() == VarDecl::Extern) {
637      LV = LValue::MakeAddr(CGM.GetAddrOfGlobalVar(VD),
638                            E->getType().getCVRQualifiers());
639    }
640    else {
641      llvm::Value *V = LocalDeclMap[VD];
642      assert(V && "BlockVarDecl not entered in LocalDeclMap?");
643      LV = LValue::MakeAddr(V, E->getType().getCVRQualifiers());
644    }
645    if (VD->isBlockVarDecl() &&
646        (VD->getStorageClass() == VarDecl::Static ||
647         VD->getStorageClass() == VarDecl::Extern))
648      SetVarDeclObjCAttribute(getContext(), VD, E->getType(), LV);
649    return LV;
650  } else if (VD && VD->isFileVarDecl()) {
651    LValue LV = LValue::MakeAddr(CGM.GetAddrOfGlobalVar(VD),
652                                 E->getType().getCVRQualifiers());
653    SetVarDeclObjCAttribute(getContext(), VD, E->getType(), LV);
654    return LV;
655  } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(E->getDecl())) {
656    return LValue::MakeAddr(CGM.GetAddrOfFunction(FD),
657                            E->getType().getCVRQualifiers());
658  }
659  else if (const ImplicitParamDecl *IPD =
660      dyn_cast<ImplicitParamDecl>(E->getDecl())) {
661    llvm::Value *V = LocalDeclMap[IPD];
662    assert(V && "BlockVarDecl not entered in LocalDeclMap?");
663    return LValue::MakeAddr(V, E->getType().getCVRQualifiers());
664  }
665  assert(0 && "Unimp declref");
666  //an invalid LValue, but the assert will
667  //ensure that this point is never reached.
668  return LValue();
669}
670
671LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
672  // __extension__ doesn't affect lvalue-ness.
673  if (E->getOpcode() == UnaryOperator::Extension)
674    return EmitLValue(E->getSubExpr());
675
676  QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
677  switch (E->getOpcode()) {
678  default: assert(0 && "Unknown unary operator lvalue!");
679  case UnaryOperator::Deref:
680    return LValue::MakeAddr(EmitScalarExpr(E->getSubExpr()),
681                            ExprTy->getAsPointerType()->getPointeeType()
682                                    .getCVRQualifiers());
683  case UnaryOperator::Real:
684  case UnaryOperator::Imag:
685    LValue LV = EmitLValue(E->getSubExpr());
686    unsigned Idx = E->getOpcode() == UnaryOperator::Imag;
687    return LValue::MakeAddr(Builder.CreateStructGEP(LV.getAddress(),
688                                                    Idx, "idx"),
689                            ExprTy.getCVRQualifiers());
690  }
691}
692
693LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
694  return LValue::MakeAddr(CGM.GetAddrOfConstantStringFromLiteral(E), 0);
695}
696
697LValue CodeGenFunction::EmitPredefinedFunctionName(unsigned Type) {
698  std::string GlobalVarName;
699
700  switch (Type) {
701    default:
702      assert(0 && "Invalid type");
703    case PredefinedExpr::Func:
704      GlobalVarName = "__func__.";
705      break;
706    case PredefinedExpr::Function:
707      GlobalVarName = "__FUNCTION__.";
708      break;
709    case PredefinedExpr::PrettyFunction:
710      // FIXME:: Demangle C++ method names
711      GlobalVarName = "__PRETTY_FUNCTION__.";
712      break;
713  }
714
715  std::string FunctionName;
716  if(const FunctionDecl *FD = dyn_cast<FunctionDecl>(CurFuncDecl)) {
717    FunctionName = CGM.getMangledName(FD)->getName();
718  } else {
719    // Just get the mangled name.
720    FunctionName = CurFn->getName();
721  }
722
723  GlobalVarName += FunctionName;
724  llvm::Constant *C =
725    CGM.GetAddrOfConstantCString(FunctionName, GlobalVarName.c_str());
726  return LValue::MakeAddr(C, 0);
727}
728
729LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
730  switch (E->getIdentType()) {
731  default:
732    return EmitUnsupportedLValue(E, "predefined expression");
733  case PredefinedExpr::Func:
734  case PredefinedExpr::Function:
735  case PredefinedExpr::PrettyFunction:
736    return EmitPredefinedFunctionName(E->getIdentType());
737  }
738}
739
740LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E) {
741  // The index must always be an integer, which is not an aggregate.  Emit it.
742  llvm::Value *Idx = EmitScalarExpr(E->getIdx());
743
744  // If the base is a vector type, then we are forming a vector element lvalue
745  // with this subscript.
746  if (E->getBase()->getType()->isVectorType()) {
747    // Emit the vector as an lvalue to get its address.
748    LValue LHS = EmitLValue(E->getBase());
749    assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
750    // FIXME: This should properly sign/zero/extend or truncate Idx to i32.
751    return LValue::MakeVectorElt(LHS.getAddress(), Idx,
752      E->getBase()->getType().getCVRQualifiers());
753  }
754
755  // The base must be a pointer, which is not an aggregate.  Emit it.
756  llvm::Value *Base = EmitScalarExpr(E->getBase());
757
758  // Extend or truncate the index type to 32 or 64-bits.
759  QualType IdxTy  = E->getIdx()->getType();
760  bool IdxSigned = IdxTy->isSignedIntegerType();
761  unsigned IdxBitwidth = cast<llvm::IntegerType>(Idx->getType())->getBitWidth();
762  if (IdxBitwidth != LLVMPointerWidth)
763    Idx = Builder.CreateIntCast(Idx, llvm::IntegerType::get(LLVMPointerWidth),
764                                IdxSigned, "idxprom");
765
766  // We know that the pointer points to a type of the correct size, unless the
767  // size is a VLA.
768  if (const VariableArrayType *VAT =
769        getContext().getAsVariableArrayType(E->getType())) {
770    llvm::Value *VLASize = VLASizeMap[VAT];
771
772    Idx = Builder.CreateMul(Idx, VLASize);
773
774    QualType BaseType = getContext().getBaseElementType(VAT);
775
776    uint64_t BaseTypeSize = getContext().getTypeSize(BaseType) / 8;
777    Idx = Builder.CreateUDiv(Idx,
778                             llvm::ConstantInt::get(Idx->getType(),
779                                                    BaseTypeSize));
780  }
781
782  QualType ExprTy = getContext().getCanonicalType(E->getBase()->getType());
783
784  return LValue::MakeAddr(Builder.CreateGEP(Base, Idx, "arrayidx"),
785                          ExprTy->getAsPointerType()->getPointeeType()
786                               .getCVRQualifiers());
787}
788
789static
790llvm::Constant *GenerateConstantVector(llvm::SmallVector<unsigned, 4> &Elts) {
791  llvm::SmallVector<llvm::Constant *, 4> CElts;
792
793  for (unsigned i = 0, e = Elts.size(); i != e; ++i)
794    CElts.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, Elts[i]));
795
796  return llvm::ConstantVector::get(&CElts[0], CElts.size());
797}
798
799LValue CodeGenFunction::
800EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
801  // Emit the base vector as an l-value.
802  LValue Base = EmitLValue(E->getBase());
803
804  // Encode the element access list into a vector of unsigned indices.
805  llvm::SmallVector<unsigned, 4> Indices;
806  E->getEncodedElementAccess(Indices);
807
808  if (Base.isSimple()) {
809    llvm::Constant *CV = GenerateConstantVector(Indices);
810    return LValue::MakeExtVectorElt(Base.getAddress(), CV,
811                                   E->getBase()->getType().getCVRQualifiers());
812  }
813  assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
814
815  llvm::Constant *BaseElts = Base.getExtVectorElts();
816  llvm::SmallVector<llvm::Constant *, 4> CElts;
817
818  for (unsigned i = 0, e = Indices.size(); i != e; ++i) {
819    if (isa<llvm::ConstantAggregateZero>(BaseElts))
820      CElts.push_back(llvm::ConstantInt::get(llvm::Type::Int32Ty, 0));
821    else
822      CElts.push_back(BaseElts->getOperand(Indices[i]));
823  }
824  llvm::Constant *CV = llvm::ConstantVector::get(&CElts[0], CElts.size());
825  return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV,
826                                  E->getBase()->getType().getCVRQualifiers());
827}
828
829LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
830  bool isUnion = false;
831  bool isIvar = false;
832  Expr *BaseExpr = E->getBase();
833  llvm::Value *BaseValue = NULL;
834  unsigned CVRQualifiers=0;
835
836  // If this is s.x, emit s as an lvalue.  If it is s->x, emit s as a scalar.
837  if (E->isArrow()) {
838    BaseValue = EmitScalarExpr(BaseExpr);
839    const PointerType *PTy =
840      cast<PointerType>(getContext().getCanonicalType(BaseExpr->getType()));
841    if (PTy->getPointeeType()->isUnionType())
842      isUnion = true;
843    CVRQualifiers = PTy->getPointeeType().getCVRQualifiers();
844  }
845  else if (BaseExpr->getStmtClass() == Expr::ObjCPropertyRefExprClass ||
846           BaseExpr->getStmtClass() == Expr::ObjCKVCRefExprClass) {
847    RValue RV = EmitObjCPropertyGet(BaseExpr);
848    BaseValue = RV.getAggregateAddr();
849    if (BaseExpr->getType()->isUnionType())
850      isUnion = true;
851    CVRQualifiers = BaseExpr->getType().getCVRQualifiers();
852  }
853  else {
854    LValue BaseLV = EmitLValue(BaseExpr);
855    if (BaseLV.isObjCIvar())
856      isIvar = true;
857    // FIXME: this isn't right for bitfields.
858    BaseValue = BaseLV.getAddress();
859    if (BaseExpr->getType()->isUnionType())
860      isUnion = true;
861    CVRQualifiers = BaseExpr->getType().getCVRQualifiers();
862  }
863
864  FieldDecl *Field = dyn_cast<FieldDecl>(E->getMemberDecl());
865  // FIXME: Handle non-field member expressions
866  assert(Field && "No code generation for non-field member references");
867  LValue MemExpLV =  EmitLValueForField(BaseValue, Field, isUnion, CVRQualifiers);
868  LValue::SetObjCIvar(MemExpLV, isIvar);
869  return MemExpLV;
870}
871
872LValue CodeGenFunction::EmitLValueForBitfield(llvm::Value* BaseValue,
873                                              FieldDecl* Field,
874                                              unsigned CVRQualifiers) {
875   unsigned idx = CGM.getTypes().getLLVMFieldNo(Field);
876  // FIXME: CodeGenTypes should expose a method to get the appropriate
877  // type for FieldTy (the appropriate type is ABI-dependent).
878  const llvm::Type *FieldTy = CGM.getTypes().ConvertTypeForMem(Field->getType());
879  const llvm::PointerType *BaseTy =
880  cast<llvm::PointerType>(BaseValue->getType());
881  unsigned AS = BaseTy->getAddressSpace();
882  BaseValue = Builder.CreateBitCast(BaseValue,
883                                    llvm::PointerType::get(FieldTy, AS),
884                                    "tmp");
885  llvm::Value *V = Builder.CreateGEP(BaseValue,
886                              llvm::ConstantInt::get(llvm::Type::Int32Ty, idx),
887                              "tmp");
888
889  CodeGenTypes::BitFieldInfo bitFieldInfo =
890    CGM.getTypes().getBitFieldInfo(Field);
891  return LValue::MakeBitfield(V, bitFieldInfo.Begin, bitFieldInfo.Size,
892                              Field->getType()->isSignedIntegerType(),
893                            Field->getType().getCVRQualifiers()|CVRQualifiers);
894}
895
896LValue CodeGenFunction::EmitLValueForField(llvm::Value* BaseValue,
897                                           FieldDecl* Field,
898                                           bool isUnion,
899                                           unsigned CVRQualifiers)
900{
901  if (Field->isBitField())
902    return EmitLValueForBitfield(BaseValue, Field, CVRQualifiers);
903
904  unsigned idx = CGM.getTypes().getLLVMFieldNo(Field);
905  llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx, "tmp");
906
907  // Match union field type.
908  if (isUnion) {
909    const llvm::Type *FieldTy =
910      CGM.getTypes().ConvertTypeForMem(Field->getType());
911    const llvm::PointerType * BaseTy =
912      cast<llvm::PointerType>(BaseValue->getType());
913    unsigned AS = BaseTy->getAddressSpace();
914    V = Builder.CreateBitCast(V,
915                              llvm::PointerType::get(FieldTy, AS),
916                              "tmp");
917  }
918
919  LValue LV =
920    LValue::MakeAddr(V,
921                     Field->getType().getCVRQualifiers()|CVRQualifiers);
922  if (const ObjCGCAttr *A = Field->getAttr<ObjCGCAttr>()) {
923    ObjCGCAttr::GCAttrTypes attrType = A->getType();
924    // __weak attribute on a field is ignored.
925    LValue::SetObjCType(false, attrType == ObjCGCAttr::Strong, LV);
926  }
927  else if (CGM.getLangOptions().ObjC1 &&
928           CGM.getLangOptions().getGCMode() != LangOptions::NonGC) {
929    QualType ExprTy = Field->getType();
930    if (getContext().isObjCObjectPointerType(ExprTy))
931      LValue::SetObjCType(false, true, LV);
932  }
933  return LV;
934}
935
936LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr* E)
937{
938  const llvm::Type *LTy = ConvertType(E->getType());
939  llvm::Value *DeclPtr = CreateTempAlloca(LTy, ".compoundliteral");
940
941  const Expr* InitExpr = E->getInitializer();
942  LValue Result = LValue::MakeAddr(DeclPtr, E->getType().getCVRQualifiers());
943
944  if (E->getType()->isComplexType()) {
945    EmitComplexExprIntoAddr(InitExpr, DeclPtr, false);
946  } else if (hasAggregateLLVMType(E->getType())) {
947    EmitAnyExpr(InitExpr, DeclPtr, false);
948  } else {
949    EmitStoreThroughLValue(EmitAnyExpr(InitExpr), Result, E->getType());
950  }
951
952  return Result;
953}
954
955//===--------------------------------------------------------------------===//
956//                             Expression Emission
957//===--------------------------------------------------------------------===//
958
959
960RValue CodeGenFunction::EmitCallExpr(const CallExpr *E) {
961  if (const ImplicitCastExpr *IcExpr =
962      dyn_cast<const ImplicitCastExpr>(E->getCallee()))
963    if (const DeclRefExpr *DRExpr =
964        dyn_cast<const DeclRefExpr>(IcExpr->getSubExpr()))
965      if (const FunctionDecl *FDecl =
966          dyn_cast<const FunctionDecl>(DRExpr->getDecl()))
967        if (unsigned builtinID = FDecl->getBuiltinID())
968          return EmitBuiltinExpr(builtinID, E);
969
970  if (E->getCallee()->getType()->isBlockPointerType())
971    return EmitBlockCallExpr(E);
972
973  llvm::Value *Callee = EmitScalarExpr(E->getCallee());
974  return EmitCallExpr(Callee, E->getCallee()->getType(),
975                      E->arg_begin(), E->arg_end());
976}
977
978RValue CodeGenFunction::EmitCallExpr(Expr *FnExpr,
979                                     CallExpr::const_arg_iterator ArgBeg,
980                                     CallExpr::const_arg_iterator ArgEnd) {
981
982  llvm::Value *Callee = EmitScalarExpr(FnExpr);
983  return EmitCallExpr(Callee, FnExpr->getType(), ArgBeg, ArgEnd);
984}
985
986LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
987  // Can only get l-value for binary operator expressions which are a
988  // simple assignment of aggregate type.
989  if (E->getOpcode() != BinaryOperator::Assign)
990    return EmitUnsupportedLValue(E, "binary l-value expression");
991
992  llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType()));
993  EmitAggExpr(E, Temp, false);
994  // FIXME: Are these qualifiers correct?
995  return LValue::MakeAddr(Temp, E->getType().getCVRQualifiers());
996}
997
998LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
999  // Can only get l-value for call expression returning aggregate type
1000  RValue RV = EmitCallExpr(E);
1001  return LValue::MakeAddr(RV.getAggregateAddr(),
1002                          E->getType().getCVRQualifiers());
1003}
1004
1005LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
1006  // FIXME: This shouldn't require another copy.
1007  llvm::Value *Temp = CreateTempAlloca(ConvertType(E->getType()));
1008  EmitAggExpr(E, Temp, false);
1009  return LValue::MakeAddr(Temp, E->getType().getCVRQualifiers());
1010}
1011
1012LValue
1013CodeGenFunction::EmitCXXConditionDeclLValue(const CXXConditionDeclExpr *E) {
1014  EmitLocalBlockVarDecl(*E->getVarDecl());
1015  return EmitDeclRefLValue(E);
1016}
1017
1018LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
1019  // Can only get l-value for message expression returning aggregate type
1020  RValue RV = EmitObjCMessageExpr(E);
1021  // FIXME: can this be volatile?
1022  return LValue::MakeAddr(RV.getAggregateAddr(),
1023                          E->getType().getCVRQualifiers());
1024}
1025
1026llvm::Value *CodeGenFunction::EmitIvarOffset(ObjCInterfaceDecl *Interface,
1027                                             const ObjCIvarDecl *Ivar) {
1028  // Objective-C objects are traditionally C structures with their layout
1029  // defined at compile-time.  In some implementations, their layout is not
1030  // defined until run time in order to allow instance variables to be added to
1031  // a class without recompiling all of the subclasses.  If this is the case
1032  // then the CGObjCRuntime subclass must return true to LateBoundIvars and
1033  // implement the lookup itself.
1034  if (CGM.getObjCRuntime().LateBoundIVars())
1035    assert(0 && "late-bound ivars are unsupported");
1036  return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
1037}
1038
1039LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
1040                                          llvm::Value *BaseValue,
1041                                          const ObjCIvarDecl *Ivar,
1042                                          const FieldDecl *Field,
1043                                          unsigned CVRQualifiers) {
1044  // See comment in EmitIvarOffset.
1045  if (CGM.getObjCRuntime().LateBoundIVars())
1046    assert(0 && "late-bound ivars are unsupported");
1047
1048  LValue LV =  CGM.getObjCRuntime().EmitObjCValueForIvar(*this,
1049                                                         ObjectTy,
1050                                                         BaseValue, Ivar, Field,
1051                                                         CVRQualifiers);
1052  SetVarDeclObjCAttribute(getContext(), Ivar, Ivar->getType(), LV);
1053  return LV;
1054}
1055
1056LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
1057  // FIXME: A lot of the code below could be shared with EmitMemberExpr.
1058  llvm::Value *BaseValue = 0;
1059  const Expr *BaseExpr = E->getBase();
1060  unsigned CVRQualifiers = 0;
1061  QualType ObjectTy;
1062  if (E->isArrow()) {
1063    BaseValue = EmitScalarExpr(BaseExpr);
1064    const PointerType *PTy =
1065      cast<PointerType>(getContext().getCanonicalType(BaseExpr->getType()));
1066    ObjectTy = PTy->getPointeeType();
1067    CVRQualifiers = ObjectTy.getCVRQualifiers();
1068  } else {
1069    LValue BaseLV = EmitLValue(BaseExpr);
1070    // FIXME: this isn't right for bitfields.
1071    BaseValue = BaseLV.getAddress();
1072    ObjectTy = BaseExpr->getType();
1073    CVRQualifiers = ObjectTy.getCVRQualifiers();
1074  }
1075
1076  return EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
1077                           getContext().getFieldDecl(E), CVRQualifiers);
1078}
1079
1080LValue
1081CodeGenFunction::EmitObjCPropertyRefLValue(const ObjCPropertyRefExpr *E) {
1082  // This is a special l-value that just issues sends when we load or
1083  // store through it.
1084  return LValue::MakePropertyRef(E, E->getType().getCVRQualifiers());
1085}
1086
1087LValue
1088CodeGenFunction::EmitObjCKVCRefLValue(const ObjCKVCRefExpr *E) {
1089  // This is a special l-value that just issues sends when we load or
1090  // store through it.
1091  return LValue::MakeKVCRef(E, E->getType().getCVRQualifiers());
1092}
1093
1094LValue
1095CodeGenFunction::EmitObjCSuperExpr(const ObjCSuperExpr *E) {
1096  return EmitUnsupportedLValue(E, "use of super");
1097}
1098
1099RValue CodeGenFunction::EmitCallExpr(llvm::Value *Callee, QualType CalleeType,
1100                                     CallExpr::const_arg_iterator ArgBeg,
1101                                     CallExpr::const_arg_iterator ArgEnd) {
1102  // Get the actual function type. The callee type will always be a
1103  // pointer to function type or a block pointer type.
1104  QualType ResultType;
1105  if (const BlockPointerType *BPT = dyn_cast<BlockPointerType>(CalleeType)) {
1106    ResultType = BPT->getPointeeType()->getAsFunctionType()->getResultType();
1107  } else {
1108    assert(CalleeType->isFunctionPointerType() &&
1109           "Call must have function pointer type!");
1110    QualType FnType = CalleeType->getAsPointerType()->getPointeeType();
1111    ResultType = FnType->getAsFunctionType()->getResultType();
1112  }
1113
1114  CallArgList Args;
1115  for (CallExpr::const_arg_iterator I = ArgBeg; I != ArgEnd; ++I)
1116    Args.push_back(std::make_pair(EmitAnyExprToTemp(*I),
1117                                  I->getType()));
1118
1119  return EmitCall(CGM.getTypes().getFunctionInfo(ResultType, Args),
1120                  Callee, Args);
1121}
1122