CGExprComplex.cpp revision de7fb8413b13651fd85b7125d08b3c9ac2816d9d 
1//===--- CGExprComplex.cpp - Emit LLVM Code for Complex Exprs -------------===//
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 with complex types as LLVM code.
11//
12//===----------------------------------------------------------------------===//
13
14#include "CodeGenFunction.h"
15#include "CodeGenModule.h"
16#include "clang/AST/ASTContext.h"
17#include "clang/AST/StmtVisitor.h"
18#include "llvm/Constants.h"
19#include "llvm/Function.h"
20#include "llvm/ADT/SmallString.h"
21#include "llvm/Support/Compiler.h"
22using namespace clang;
23using namespace CodeGen;
24
25//===----------------------------------------------------------------------===//
26//                        Complex Expression Emitter
27//===----------------------------------------------------------------------===//
28
29typedef CodeGenFunction::ComplexPairTy ComplexPairTy;
30
31namespace  {
32class VISIBILITY_HIDDEN ComplexExprEmitter
33  : public StmtVisitor<ComplexExprEmitter, ComplexPairTy> {
34  CodeGenFunction &CGF;
35  llvm::IRBuilder<> &Builder;
36public:
37  ComplexExprEmitter(CodeGenFunction &cgf) : CGF(cgf), Builder(CGF.Builder) {
38  }
39
40
41  //===--------------------------------------------------------------------===//
42  //                               Utilities
43  //===--------------------------------------------------------------------===//
44
45  /// EmitLoadOfLValue - Given an expression with complex type that represents a
46  /// value l-value, this method emits the address of the l-value, then loads
47  /// and returns the result.
48  ComplexPairTy EmitLoadOfLValue(const Expr *E) {
49    LValue LV = CGF.EmitLValue(E);
50    // FIXME: Volatile
51    return EmitLoadOfComplex(LV.getAddress(), false);
52  }
53
54  /// EmitLoadOfComplex - Given a pointer to a complex value, emit code to load
55  /// the real and imaginary pieces.
56  ComplexPairTy EmitLoadOfComplex(llvm::Value *SrcPtr, bool isVolatile);
57
58  /// EmitStoreOfComplex - Store the specified real/imag parts into the
59  /// specified value pointer.
60  void EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *ResPtr, bool isVol);
61
62  /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
63  ComplexPairTy EmitComplexToComplexCast(ComplexPairTy Val, QualType SrcType,
64                                         QualType DestType);
65
66  //===--------------------------------------------------------------------===//
67  //                            Visitor Methods
68  //===--------------------------------------------------------------------===//
69
70  ComplexPairTy VisitStmt(Stmt *S) {
71    S->dump(CGF.getContext().getSourceManager());
72    assert(0 && "Stmt can't have complex result type!");
73    return ComplexPairTy();
74  }
75  ComplexPairTy VisitExpr(Expr *S);
76  ComplexPairTy VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr());}
77  ComplexPairTy VisitImaginaryLiteral(const ImaginaryLiteral *IL);
78
79  // l-values.
80  ComplexPairTy VisitDeclRefExpr(const Expr *E) { return EmitLoadOfLValue(E); }
81  ComplexPairTy VisitArraySubscriptExpr(Expr *E) { return EmitLoadOfLValue(E); }
82  ComplexPairTy VisitMemberExpr(const Expr *E) { return EmitLoadOfLValue(E); }
83
84  // FIXME: CompoundLiteralExpr
85
86  ComplexPairTy EmitCast(Expr *Op, QualType DestTy);
87  ComplexPairTy VisitImplicitCastExpr(ImplicitCastExpr *E) {
88    // Unlike for scalars, we don't have to worry about function->ptr demotion
89    // here.
90    return EmitCast(E->getSubExpr(), E->getType());
91  }
92  ComplexPairTy VisitCastExpr(CastExpr *E) {
93    return EmitCast(E->getSubExpr(), E->getType());
94  }
95  ComplexPairTy VisitCallExpr(const CallExpr *E);
96  ComplexPairTy VisitStmtExpr(const StmtExpr *E);
97  ComplexPairTy VisitOverloadExpr(const OverloadExpr *OE);
98
99  // Operators.
100  ComplexPairTy VisitPrePostIncDec(const UnaryOperator *E,
101                                   bool isInc, bool isPre);
102  ComplexPairTy VisitUnaryPostDec(const UnaryOperator *E) {
103    return VisitPrePostIncDec(E, false, false);
104  }
105  ComplexPairTy VisitUnaryPostInc(const UnaryOperator *E) {
106    return VisitPrePostIncDec(E, true, false);
107  }
108  ComplexPairTy VisitUnaryPreDec(const UnaryOperator *E) {
109    return VisitPrePostIncDec(E, false, true);
110  }
111  ComplexPairTy VisitUnaryPreInc(const UnaryOperator *E) {
112    return VisitPrePostIncDec(E, true, true);
113  }
114  ComplexPairTy VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); }
115  ComplexPairTy VisitUnaryPlus     (const UnaryOperator *E) {
116    return Visit(E->getSubExpr());
117  }
118  ComplexPairTy VisitUnaryMinus    (const UnaryOperator *E);
119  ComplexPairTy VisitUnaryNot      (const UnaryOperator *E);
120  // LNot,SizeOf,AlignOf,Real,Imag never return complex.
121  ComplexPairTy VisitUnaryExtension(const UnaryOperator *E) {
122    return Visit(E->getSubExpr());
123  }
124  ComplexPairTy VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
125    return Visit(DAE->getExpr());
126  }
127
128  struct BinOpInfo {
129    ComplexPairTy LHS;
130    ComplexPairTy RHS;
131    QualType Ty;  // Computation Type.
132  };
133
134  BinOpInfo EmitBinOps(const BinaryOperator *E);
135  ComplexPairTy EmitCompoundAssign(const CompoundAssignOperator *E,
136                                   ComplexPairTy (ComplexExprEmitter::*Func)
137                                   (const BinOpInfo &));
138
139  ComplexPairTy EmitBinAdd(const BinOpInfo &Op);
140  ComplexPairTy EmitBinSub(const BinOpInfo &Op);
141  ComplexPairTy EmitBinMul(const BinOpInfo &Op);
142  ComplexPairTy EmitBinDiv(const BinOpInfo &Op);
143
144  ComplexPairTy VisitBinMul(const BinaryOperator *E) {
145    return EmitBinMul(EmitBinOps(E));
146  }
147  ComplexPairTy VisitBinAdd(const BinaryOperator *E) {
148    return EmitBinAdd(EmitBinOps(E));
149  }
150  ComplexPairTy VisitBinSub(const BinaryOperator *E) {
151    return EmitBinSub(EmitBinOps(E));
152  }
153  ComplexPairTy VisitBinDiv(const BinaryOperator *E) {
154    return EmitBinDiv(EmitBinOps(E));
155  }
156
157  // Compound assignments.
158  ComplexPairTy VisitBinAddAssign(const CompoundAssignOperator *E) {
159    return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinAdd);
160  }
161  ComplexPairTy VisitBinSubAssign(const CompoundAssignOperator *E) {
162    return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinSub);
163  }
164  ComplexPairTy VisitBinMulAssign(const CompoundAssignOperator *E) {
165    return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinMul);
166  }
167  ComplexPairTy VisitBinDivAssign(const CompoundAssignOperator *E) {
168    return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinDiv);
169  }
170
171  // GCC rejects rem/and/or/xor for integer complex.
172  // Logical and/or always return int, never complex.
173
174  // No comparisons produce a complex result.
175  ComplexPairTy VisitBinAssign     (const BinaryOperator *E);
176  ComplexPairTy VisitBinComma      (const BinaryOperator *E);
177
178
179  ComplexPairTy VisitConditionalOperator(const ConditionalOperator *CO);
180  ComplexPairTy VisitChooseExpr(ChooseExpr *CE);
181
182  ComplexPairTy VisitInitListExpr(InitListExpr *E);
183};
184}  // end anonymous namespace.
185
186//===----------------------------------------------------------------------===//
187//                                Utilities
188//===----------------------------------------------------------------------===//
189
190/// EmitLoadOfComplex - Given an RValue reference for a complex, emit code to
191/// load the real and imaginary pieces, returning them as Real/Imag.
192ComplexPairTy ComplexExprEmitter::EmitLoadOfComplex(llvm::Value *SrcPtr,
193                                                    bool isVolatile) {
194  llvm::SmallString<64> Name(SrcPtr->getNameStart(),
195                             SrcPtr->getNameStart()+SrcPtr->getNameLen());
196
197  Name += ".realp";
198  llvm::Value *RealPtr = Builder.CreateStructGEP(SrcPtr, 0, Name.c_str());
199
200  Name.pop_back();  // .realp -> .real
201  llvm::Value *Real = Builder.CreateLoad(RealPtr, isVolatile, Name.c_str());
202
203  Name.resize(Name.size()-4); // .real -> .imagp
204  Name += "imagp";
205
206  llvm::Value *ImagPtr = Builder.CreateStructGEP(SrcPtr, 1, Name.c_str());
207
208  Name.pop_back();  // .imagp -> .imag
209  llvm::Value *Imag = Builder.CreateLoad(ImagPtr, isVolatile, Name.c_str());
210  return ComplexPairTy(Real, Imag);
211}
212
213/// EmitStoreOfComplex - Store the specified real/imag parts into the
214/// specified value pointer.
215void ComplexExprEmitter::EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *Ptr,
216                                            bool isVolatile) {
217  llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, "real");
218  llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, "imag");
219
220  Builder.CreateStore(Val.first, RealPtr, isVolatile);
221  Builder.CreateStore(Val.second, ImagPtr, isVolatile);
222}
223
224
225
226//===----------------------------------------------------------------------===//
227//                            Visitor Methods
228//===----------------------------------------------------------------------===//
229
230ComplexPairTy ComplexExprEmitter::VisitExpr(Expr *E) {
231  CGF.WarnUnsupported(E, "complex expression");
232  const llvm::Type *EltTy =
233    CGF.ConvertType(E->getType()->getAsComplexType()->getElementType());
234  llvm::Value *U = llvm::UndefValue::get(EltTy);
235  return ComplexPairTy(U, U);
236}
237
238ComplexPairTy ComplexExprEmitter::
239VisitImaginaryLiteral(const ImaginaryLiteral *IL) {
240  llvm::Value *Imag = CGF.EmitScalarExpr(IL->getSubExpr());
241  return ComplexPairTy(llvm::Constant::getNullValue(Imag->getType()), Imag);
242}
243
244
245ComplexPairTy ComplexExprEmitter::VisitCallExpr(const CallExpr *E) {
246  return CGF.EmitCallExpr(E).getComplexVal();
247}
248
249ComplexPairTy ComplexExprEmitter::VisitOverloadExpr(const OverloadExpr *E) {
250  return CGF.EmitCallExpr(E->getFn(), E->arg_begin(),
251                          E->arg_end(CGF.getContext())).getComplexVal();
252}
253
254ComplexPairTy ComplexExprEmitter::VisitStmtExpr(const StmtExpr *E) {
255  return CGF.EmitCompoundStmt(*E->getSubStmt(), true).getComplexVal();
256}
257
258/// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
259ComplexPairTy ComplexExprEmitter::EmitComplexToComplexCast(ComplexPairTy Val,
260                                                           QualType SrcType,
261                                                           QualType DestType) {
262  // Get the src/dest element type.
263  SrcType = SrcType->getAsComplexType()->getElementType();
264  DestType = DestType->getAsComplexType()->getElementType();
265
266  // C99 6.3.1.6: When a value of complextype is converted to another
267  // complex type, both the real and imaginary parts followthe conversion
268  // rules for the corresponding real types.
269  Val.first = CGF.EmitScalarConversion(Val.first, SrcType, DestType);
270  Val.second = CGF.EmitScalarConversion(Val.second, SrcType, DestType);
271  return Val;
272}
273
274ComplexPairTy ComplexExprEmitter::EmitCast(Expr *Op, QualType DestTy) {
275  // Two cases here: cast from (complex to complex) and (scalar to complex).
276  if (Op->getType()->isAnyComplexType())
277    return EmitComplexToComplexCast(Visit(Op), Op->getType(), DestTy);
278
279  // C99 6.3.1.7: When a value of real type is converted to a complex type, the
280  // real part of the complex  result value is determined by the rules of
281  // conversion to the corresponding real type and the imaginary part of the
282  // complex result value is a positive zero or an unsigned zero.
283  llvm::Value *Elt = CGF.EmitScalarExpr(Op);
284
285  // Convert the input element to the element type of the complex.
286  DestTy = DestTy->getAsComplexType()->getElementType();
287  Elt = CGF.EmitScalarConversion(Elt, Op->getType(), DestTy);
288
289  // Return (realval, 0).
290  return ComplexPairTy(Elt, llvm::Constant::getNullValue(Elt->getType()));
291}
292
293ComplexPairTy ComplexExprEmitter::VisitPrePostIncDec(const UnaryOperator *E,
294                                                     bool isInc, bool isPre) {
295  LValue LV = CGF.EmitLValue(E->getSubExpr());
296  // FIXME: Handle volatile!
297  ComplexPairTy InVal = EmitLoadOfComplex(LV.getAddress(), false);
298
299  uint64_t AmountVal = isInc ? 1 : -1;
300
301  llvm::Value *NextVal;
302  if (isa<llvm::IntegerType>(InVal.first->getType()))
303    NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal);
304  else if (InVal.first->getType() == llvm::Type::FloatTy)
305    // FIXME: Handle long double.
306    NextVal =
307      llvm::ConstantFP::get(llvm::APFloat(static_cast<float>(AmountVal)));
308  else {
309    // FIXME: Handle long double.
310    assert(InVal.first->getType() == llvm::Type::DoubleTy);
311    NextVal =
312      llvm::ConstantFP::get(llvm::APFloat(static_cast<double>(AmountVal)));
313  }
314
315  // Add the inc/dec to the real part.
316  NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
317
318  ComplexPairTy IncVal(NextVal, InVal.second);
319
320  // Store the updated result through the lvalue.
321  EmitStoreOfComplex(IncVal, LV.getAddress(), false);  /* FIXME: Volatile */
322
323  // If this is a postinc, return the value read from memory, otherwise use the
324  // updated value.
325  return isPre ? IncVal : InVal;
326}
327
328ComplexPairTy ComplexExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
329  ComplexPairTy Op = Visit(E->getSubExpr());
330  llvm::Value *ResR = Builder.CreateNeg(Op.first,  "neg.r");
331  llvm::Value *ResI = Builder.CreateNeg(Op.second, "neg.i");
332  return ComplexPairTy(ResR, ResI);
333}
334
335ComplexPairTy ComplexExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
336  // ~(a+ib) = a + i*-b
337  ComplexPairTy Op = Visit(E->getSubExpr());
338  llvm::Value *ResI = Builder.CreateNeg(Op.second, "conj.i");
339  return ComplexPairTy(Op.first, ResI);
340}
341
342ComplexPairTy ComplexExprEmitter::EmitBinAdd(const BinOpInfo &Op) {
343  llvm::Value *ResR = Builder.CreateAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
344  llvm::Value *ResI = Builder.CreateAdd(Op.LHS.second, Op.RHS.second, "add.i");
345  return ComplexPairTy(ResR, ResI);
346}
347
348ComplexPairTy ComplexExprEmitter::EmitBinSub(const BinOpInfo &Op) {
349  llvm::Value *ResR = Builder.CreateSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
350  llvm::Value *ResI = Builder.CreateSub(Op.LHS.second, Op.RHS.second, "sub.i");
351  return ComplexPairTy(ResR, ResI);
352}
353
354
355ComplexPairTy ComplexExprEmitter::EmitBinMul(const BinOpInfo &Op) {
356  llvm::Value *ResRl = Builder.CreateMul(Op.LHS.first, Op.RHS.first, "mul.rl");
357  llvm::Value *ResRr = Builder.CreateMul(Op.LHS.second, Op.RHS.second,"mul.rr");
358  llvm::Value *ResR  = Builder.CreateSub(ResRl, ResRr, "mul.r");
359
360  llvm::Value *ResIl = Builder.CreateMul(Op.LHS.second, Op.RHS.first, "mul.il");
361  llvm::Value *ResIr = Builder.CreateMul(Op.LHS.first, Op.RHS.second, "mul.ir");
362  llvm::Value *ResI  = Builder.CreateAdd(ResIl, ResIr, "mul.i");
363  return ComplexPairTy(ResR, ResI);
364}
365
366ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
367  llvm::Value *LHSr = Op.LHS.first, *LHSi = Op.LHS.second;
368  llvm::Value *RHSr = Op.RHS.first, *RHSi = Op.RHS.second;
369
370  // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
371  llvm::Value *Tmp1 = Builder.CreateMul(LHSr, RHSr, "tmp"); // a*c
372  llvm::Value *Tmp2 = Builder.CreateMul(LHSi, RHSi, "tmp"); // b*d
373  llvm::Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2, "tmp"); // ac+bd
374
375  llvm::Value *Tmp4 = Builder.CreateMul(RHSr, RHSr, "tmp"); // c*c
376  llvm::Value *Tmp5 = Builder.CreateMul(RHSi, RHSi, "tmp"); // d*d
377  llvm::Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5, "tmp"); // cc+dd
378
379  llvm::Value *Tmp7 = Builder.CreateMul(LHSi, RHSr, "tmp"); // b*c
380  llvm::Value *Tmp8 = Builder.CreateMul(LHSr, RHSi, "tmp"); // a*d
381  llvm::Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8, "tmp"); // bc-ad
382
383  llvm::Value *DSTr, *DSTi;
384  if (Tmp3->getType()->isFloatingPoint()) {
385    DSTr = Builder.CreateFDiv(Tmp3, Tmp6, "tmp");
386    DSTi = Builder.CreateFDiv(Tmp9, Tmp6, "tmp");
387  } else {
388    if (Op.Ty->getAsComplexType()->getElementType()->isUnsignedIntegerType()) {
389      DSTr = Builder.CreateUDiv(Tmp3, Tmp6, "tmp");
390      DSTi = Builder.CreateUDiv(Tmp9, Tmp6, "tmp");
391    } else {
392      DSTr = Builder.CreateSDiv(Tmp3, Tmp6, "tmp");
393      DSTi = Builder.CreateSDiv(Tmp9, Tmp6, "tmp");
394    }
395  }
396
397  return ComplexPairTy(DSTr, DSTi);
398}
399
400ComplexExprEmitter::BinOpInfo
401ComplexExprEmitter::EmitBinOps(const BinaryOperator *E) {
402  BinOpInfo Ops;
403  Ops.LHS = Visit(E->getLHS());
404  Ops.RHS = Visit(E->getRHS());
405  Ops.Ty = E->getType();
406  return Ops;
407}
408
409
410// Compound assignments.
411ComplexPairTy ComplexExprEmitter::
412EmitCompoundAssign(const CompoundAssignOperator *E,
413                   ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&)){
414  QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType();
415
416  // Load the LHS and RHS operands.
417  LValue LHSLV = CGF.EmitLValue(E->getLHS());
418
419  BinOpInfo OpInfo;
420  OpInfo.Ty = E->getComputationType();
421
422  // We know the LHS is a complex lvalue.
423  OpInfo.LHS = EmitLoadOfComplex(LHSLV.getAddress(), false);// FIXME: Volatile.
424  OpInfo.LHS = EmitComplexToComplexCast(OpInfo.LHS, LHSTy, OpInfo.Ty);
425
426  // It is possible for the RHS to be complex or scalar.
427  OpInfo.RHS = EmitCast(E->getRHS(), OpInfo.Ty);
428
429  // Expand the binary operator.
430  ComplexPairTy Result = (this->*Func)(OpInfo);
431
432  // Truncate the result back to the LHS type.
433  Result = EmitComplexToComplexCast(Result, OpInfo.Ty, LHSTy);
434
435  // Store the result value into the LHS lvalue.
436  EmitStoreOfComplex(Result, LHSLV.getAddress(), false); // FIXME: VOLATILE
437  return Result;
438}
439
440ComplexPairTy ComplexExprEmitter::VisitBinAssign(const BinaryOperator *E) {
441  assert(CGF.getContext().getCanonicalType(E->getLHS()->getType()) ==
442         CGF.getContext().getCanonicalType(E->getRHS()->getType()) &&
443         "Invalid assignment");
444  // Emit the RHS.
445  ComplexPairTy Val = Visit(E->getRHS());
446
447  // Compute the address to store into.
448  LValue LHS = CGF.EmitLValue(E->getLHS());
449
450  // Store into it.
451  // FIXME: Volatility!
452  EmitStoreOfComplex(Val, LHS.getAddress(), false);
453  return Val;
454}
455
456ComplexPairTy ComplexExprEmitter::VisitBinComma(const BinaryOperator *E) {
457  CGF.EmitStmt(E->getLHS());
458  return Visit(E->getRHS());
459}
460
461ComplexPairTy ComplexExprEmitter::
462VisitConditionalOperator(const ConditionalOperator *E) {
463  llvm::BasicBlock *LHSBlock = llvm::BasicBlock::Create("cond.?");
464  llvm::BasicBlock *RHSBlock = llvm::BasicBlock::Create("cond.:");
465  llvm::BasicBlock *ContBlock = llvm::BasicBlock::Create("cond.cont");
466
467  llvm::Value *Cond = CGF.EvaluateExprAsBool(E->getCond());
468  Builder.CreateCondBr(Cond, LHSBlock, RHSBlock);
469
470  CGF.EmitBlock(LHSBlock);
471
472  // Handle the GNU extension for missing LHS.
473  assert(E->getLHS() && "Must have LHS for complex value");
474
475  ComplexPairTy LHS = Visit(E->getLHS());
476  Builder.CreateBr(ContBlock);
477  LHSBlock = Builder.GetInsertBlock();
478
479  CGF.EmitBlock(RHSBlock);
480
481  ComplexPairTy RHS = Visit(E->getRHS());
482  Builder.CreateBr(ContBlock);
483  RHSBlock = Builder.GetInsertBlock();
484
485  CGF.EmitBlock(ContBlock);
486
487  // Create a PHI node for the real part.
488  llvm::PHINode *RealPN = Builder.CreatePHI(LHS.first->getType(), "cond.r");
489  RealPN->reserveOperandSpace(2);
490  RealPN->addIncoming(LHS.first, LHSBlock);
491  RealPN->addIncoming(RHS.first, RHSBlock);
492
493  // Create a PHI node for the imaginary part.
494  llvm::PHINode *ImagPN = Builder.CreatePHI(LHS.first->getType(), "cond.i");
495  ImagPN->reserveOperandSpace(2);
496  ImagPN->addIncoming(LHS.second, LHSBlock);
497  ImagPN->addIncoming(RHS.second, RHSBlock);
498
499  return ComplexPairTy(RealPN, ImagPN);
500}
501
502ComplexPairTy ComplexExprEmitter::VisitChooseExpr(ChooseExpr *E) {
503  // Emit the LHS or RHS as appropriate.
504  return Visit(E->isConditionTrue(CGF.getContext()) ? E->getLHS() :E->getRHS());
505}
506
507ComplexPairTy ComplexExprEmitter::VisitInitListExpr(InitListExpr *E) {
508  if (E->getNumInits())
509    return Visit(E->getInit(0));
510
511  // Empty init list intializes to null
512  QualType Ty = E->getType()->getAsComplexType()->getElementType();
513  const llvm::Type* LTy = CGF.ConvertType(Ty);
514  llvm::Value* zeroConstant = llvm::Constant::getNullValue(LTy);
515  return ComplexPairTy(zeroConstant, zeroConstant);
516}
517
518//===----------------------------------------------------------------------===//
519//                         Entry Point into this File
520//===----------------------------------------------------------------------===//
521
522/// EmitComplexExpr - Emit the computation of the specified expression of
523/// complex type, ignoring the result.
524ComplexPairTy CodeGenFunction::EmitComplexExpr(const Expr *E) {
525  assert(E && E->getType()->isAnyComplexType() &&
526         "Invalid complex expression to emit");
527
528  return ComplexExprEmitter(*this).Visit(const_cast<Expr*>(E));
529}
530
531/// EmitComplexExprIntoAddr - Emit the computation of the specified expression
532/// of complex type, storing into the specified Value*.
533void CodeGenFunction::EmitComplexExprIntoAddr(const Expr *E,
534                                              llvm::Value *DestAddr,
535                                              bool DestIsVolatile) {
536  assert(E && E->getType()->isAnyComplexType() &&
537         "Invalid complex expression to emit");
538  ComplexExprEmitter Emitter(*this);
539  ComplexPairTy Val = Emitter.Visit(const_cast<Expr*>(E));
540  Emitter.EmitStoreOfComplex(Val, DestAddr, DestIsVolatile);
541}
542
543/// LoadComplexFromAddr - Load a complex number from the specified address.
544ComplexPairTy CodeGenFunction::LoadComplexFromAddr(llvm::Value *SrcAddr,
545                                                   bool SrcIsVolatile) {
546  return ComplexExprEmitter(*this).EmitLoadOfComplex(SrcAddr, SrcIsVolatile);
547}
548