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/ADT/STLExtras.h"
19 #include "llvm/ADT/SmallString.h"
20 #include "llvm/IR/Constants.h"
21 #include "llvm/IR/Function.h"
22 #include "llvm/IR/Instructions.h"
23 #include "llvm/IR/MDBuilder.h"
24 #include "llvm/IR/Metadata.h"
25 #include <algorithm>
26 using namespace clang;
27 using namespace CodeGen;
28 
29 //===----------------------------------------------------------------------===//
30 //                        Complex Expression Emitter
31 //===----------------------------------------------------------------------===//
32 
33 typedef CodeGenFunction::ComplexPairTy ComplexPairTy;
34 
35 /// Return the complex type that we are meant to emit.
36 static const ComplexType *getComplexType(QualType type) {
37   type = type.getCanonicalType();
38   if (const ComplexType *comp = dyn_cast<ComplexType>(type)) {
39     return comp;
40   } else {
41     return cast<ComplexType>(cast<AtomicType>(type)->getValueType());
42   }
43 }
44 
45 namespace  {
46 class ComplexExprEmitter
47   : public StmtVisitor<ComplexExprEmitter, ComplexPairTy> {
48   CodeGenFunction &CGF;
49   CGBuilderTy &Builder;
50   bool IgnoreReal;
51   bool IgnoreImag;
52 public:
53   ComplexExprEmitter(CodeGenFunction &cgf, bool ir=false, bool ii=false)
54     : CGF(cgf), Builder(CGF.Builder), IgnoreReal(ir), IgnoreImag(ii) {
55   }
56 
57 
58   //===--------------------------------------------------------------------===//
59   //                               Utilities
60   //===--------------------------------------------------------------------===//
61 
62   bool TestAndClearIgnoreReal() {
63     bool I = IgnoreReal;
64     IgnoreReal = false;
65     return I;
66   }
67   bool TestAndClearIgnoreImag() {
68     bool I = IgnoreImag;
69     IgnoreImag = false;
70     return I;
71   }
72 
73   /// EmitLoadOfLValue - Given an expression with complex type that represents a
74   /// value l-value, this method emits the address of the l-value, then loads
75   /// and returns the result.
76   ComplexPairTy EmitLoadOfLValue(const Expr *E) {
77     return EmitLoadOfLValue(CGF.EmitLValue(E), E->getExprLoc());
78   }
79 
80   ComplexPairTy EmitLoadOfLValue(LValue LV, SourceLocation Loc);
81 
82   /// EmitStoreOfComplex - Store the specified real/imag parts into the
83   /// specified value pointer.
84   void EmitStoreOfComplex(ComplexPairTy Val, LValue LV, bool isInit);
85 
86   /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
87   ComplexPairTy EmitComplexToComplexCast(ComplexPairTy Val, QualType SrcType,
88                                          QualType DestType);
89   /// EmitComplexToComplexCast - Emit a cast from scalar value Val to DestType.
90   ComplexPairTy EmitScalarToComplexCast(llvm::Value *Val, QualType SrcType,
91                                         QualType DestType);
92 
93   //===--------------------------------------------------------------------===//
94   //                            Visitor Methods
95   //===--------------------------------------------------------------------===//
96 
97   ComplexPairTy Visit(Expr *E) {
98     ApplyDebugLocation DL(CGF, E);
99     return StmtVisitor<ComplexExprEmitter, ComplexPairTy>::Visit(E);
100   }
101 
102   ComplexPairTy VisitStmt(Stmt *S) {
103     S->dump(CGF.getContext().getSourceManager());
104     llvm_unreachable("Stmt can't have complex result type!");
105   }
106   ComplexPairTy VisitExpr(Expr *S);
107   ComplexPairTy VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr());}
108   ComplexPairTy VisitGenericSelectionExpr(GenericSelectionExpr *GE) {
109     return Visit(GE->getResultExpr());
110   }
111   ComplexPairTy VisitImaginaryLiteral(const ImaginaryLiteral *IL);
112   ComplexPairTy
113   VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE) {
114     return Visit(PE->getReplacement());
115   }
116 
117   // l-values.
118   ComplexPairTy VisitDeclRefExpr(DeclRefExpr *E) {
119     if (CodeGenFunction::ConstantEmission result = CGF.tryEmitAsConstant(E)) {
120       if (result.isReference())
121         return EmitLoadOfLValue(result.getReferenceLValue(CGF, E),
122                                 E->getExprLoc());
123 
124       llvm::Constant *pair = result.getValue();
125       return ComplexPairTy(pair->getAggregateElement(0U),
126                            pair->getAggregateElement(1U));
127     }
128     return EmitLoadOfLValue(E);
129   }
130   ComplexPairTy VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
131     return EmitLoadOfLValue(E);
132   }
133   ComplexPairTy VisitObjCMessageExpr(ObjCMessageExpr *E) {
134     return CGF.EmitObjCMessageExpr(E).getComplexVal();
135   }
136   ComplexPairTy VisitArraySubscriptExpr(Expr *E) { return EmitLoadOfLValue(E); }
137   ComplexPairTy VisitMemberExpr(const Expr *E) { return EmitLoadOfLValue(E); }
138   ComplexPairTy VisitOpaqueValueExpr(OpaqueValueExpr *E) {
139     if (E->isGLValue())
140       return EmitLoadOfLValue(CGF.getOpaqueLValueMapping(E), E->getExprLoc());
141     return CGF.getOpaqueRValueMapping(E).getComplexVal();
142   }
143 
144   ComplexPairTy VisitPseudoObjectExpr(PseudoObjectExpr *E) {
145     return CGF.EmitPseudoObjectRValue(E).getComplexVal();
146   }
147 
148   // FIXME: CompoundLiteralExpr
149 
150   ComplexPairTy EmitCast(CastKind CK, Expr *Op, QualType DestTy);
151   ComplexPairTy VisitImplicitCastExpr(ImplicitCastExpr *E) {
152     // Unlike for scalars, we don't have to worry about function->ptr demotion
153     // here.
154     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
155   }
156   ComplexPairTy VisitCastExpr(CastExpr *E) {
157     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
158   }
159   ComplexPairTy VisitCallExpr(const CallExpr *E);
160   ComplexPairTy VisitStmtExpr(const StmtExpr *E);
161 
162   // Operators.
163   ComplexPairTy VisitPrePostIncDec(const UnaryOperator *E,
164                                    bool isInc, bool isPre) {
165     LValue LV = CGF.EmitLValue(E->getSubExpr());
166     return CGF.EmitComplexPrePostIncDec(E, LV, isInc, isPre);
167   }
168   ComplexPairTy VisitUnaryPostDec(const UnaryOperator *E) {
169     return VisitPrePostIncDec(E, false, false);
170   }
171   ComplexPairTy VisitUnaryPostInc(const UnaryOperator *E) {
172     return VisitPrePostIncDec(E, true, false);
173   }
174   ComplexPairTy VisitUnaryPreDec(const UnaryOperator *E) {
175     return VisitPrePostIncDec(E, false, true);
176   }
177   ComplexPairTy VisitUnaryPreInc(const UnaryOperator *E) {
178     return VisitPrePostIncDec(E, true, true);
179   }
180   ComplexPairTy VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); }
181   ComplexPairTy VisitUnaryPlus     (const UnaryOperator *E) {
182     TestAndClearIgnoreReal();
183     TestAndClearIgnoreImag();
184     return Visit(E->getSubExpr());
185   }
186   ComplexPairTy VisitUnaryMinus    (const UnaryOperator *E);
187   ComplexPairTy VisitUnaryNot      (const UnaryOperator *E);
188   // LNot,Real,Imag never return complex.
189   ComplexPairTy VisitUnaryExtension(const UnaryOperator *E) {
190     return Visit(E->getSubExpr());
191   }
192   ComplexPairTy VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
193     return Visit(DAE->getExpr());
194   }
195   ComplexPairTy VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) {
196     CodeGenFunction::CXXDefaultInitExprScope Scope(CGF);
197     return Visit(DIE->getExpr());
198   }
199   ComplexPairTy VisitExprWithCleanups(ExprWithCleanups *E) {
200     CGF.enterFullExpression(E);
201     CodeGenFunction::RunCleanupsScope Scope(CGF);
202     return Visit(E->getSubExpr());
203   }
204   ComplexPairTy VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E) {
205     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
206     QualType Elem = E->getType()->castAs<ComplexType>()->getElementType();
207     llvm::Constant *Null = llvm::Constant::getNullValue(CGF.ConvertType(Elem));
208     return ComplexPairTy(Null, Null);
209   }
210   ComplexPairTy VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
211     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
212     QualType Elem = E->getType()->castAs<ComplexType>()->getElementType();
213     llvm::Constant *Null =
214                        llvm::Constant::getNullValue(CGF.ConvertType(Elem));
215     return ComplexPairTy(Null, Null);
216   }
217 
218   struct BinOpInfo {
219     ComplexPairTy LHS;
220     ComplexPairTy RHS;
221     QualType Ty;  // Computation Type.
222   };
223 
224   BinOpInfo EmitBinOps(const BinaryOperator *E);
225   LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E,
226                                   ComplexPairTy (ComplexExprEmitter::*Func)
227                                   (const BinOpInfo &),
228                                   RValue &Val);
229   ComplexPairTy EmitCompoundAssign(const CompoundAssignOperator *E,
230                                    ComplexPairTy (ComplexExprEmitter::*Func)
231                                    (const BinOpInfo &));
232 
233   ComplexPairTy EmitBinAdd(const BinOpInfo &Op);
234   ComplexPairTy EmitBinSub(const BinOpInfo &Op);
235   ComplexPairTy EmitBinMul(const BinOpInfo &Op);
236   ComplexPairTy EmitBinDiv(const BinOpInfo &Op);
237 
238   ComplexPairTy EmitComplexBinOpLibCall(StringRef LibCallName,
239                                         const BinOpInfo &Op);
240 
241   ComplexPairTy VisitBinAdd(const BinaryOperator *E) {
242     return EmitBinAdd(EmitBinOps(E));
243   }
244   ComplexPairTy VisitBinSub(const BinaryOperator *E) {
245     return EmitBinSub(EmitBinOps(E));
246   }
247   ComplexPairTy VisitBinMul(const BinaryOperator *E) {
248     return EmitBinMul(EmitBinOps(E));
249   }
250   ComplexPairTy VisitBinDiv(const BinaryOperator *E) {
251     return EmitBinDiv(EmitBinOps(E));
252   }
253 
254   // Compound assignments.
255   ComplexPairTy VisitBinAddAssign(const CompoundAssignOperator *E) {
256     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinAdd);
257   }
258   ComplexPairTy VisitBinSubAssign(const CompoundAssignOperator *E) {
259     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinSub);
260   }
261   ComplexPairTy VisitBinMulAssign(const CompoundAssignOperator *E) {
262     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinMul);
263   }
264   ComplexPairTy VisitBinDivAssign(const CompoundAssignOperator *E) {
265     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinDiv);
266   }
267 
268   // GCC rejects rem/and/or/xor for integer complex.
269   // Logical and/or always return int, never complex.
270 
271   // No comparisons produce a complex result.
272 
273   LValue EmitBinAssignLValue(const BinaryOperator *E,
274                              ComplexPairTy &Val);
275   ComplexPairTy VisitBinAssign     (const BinaryOperator *E);
276   ComplexPairTy VisitBinComma      (const BinaryOperator *E);
277 
278 
279   ComplexPairTy
280   VisitAbstractConditionalOperator(const AbstractConditionalOperator *CO);
281   ComplexPairTy VisitChooseExpr(ChooseExpr *CE);
282 
283   ComplexPairTy VisitInitListExpr(InitListExpr *E);
284 
285   ComplexPairTy VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
286     return EmitLoadOfLValue(E);
287   }
288 
289   ComplexPairTy VisitVAArgExpr(VAArgExpr *E);
290 
291   ComplexPairTy VisitAtomicExpr(AtomicExpr *E) {
292     return CGF.EmitAtomicExpr(E).getComplexVal();
293   }
294 };
295 }  // end anonymous namespace.
296 
297 //===----------------------------------------------------------------------===//
298 //                                Utilities
299 //===----------------------------------------------------------------------===//
300 
301 /// EmitLoadOfLValue - Given an RValue reference for a complex, emit code to
302 /// load the real and imaginary pieces, returning them as Real/Imag.
303 ComplexPairTy ComplexExprEmitter::EmitLoadOfLValue(LValue lvalue,
304                                                    SourceLocation loc) {
305   assert(lvalue.isSimple() && "non-simple complex l-value?");
306   if (lvalue.getType()->isAtomicType())
307     return CGF.EmitAtomicLoad(lvalue, loc).getComplexVal();
308 
309   llvm::Value *SrcPtr = lvalue.getAddress();
310   bool isVolatile = lvalue.isVolatileQualified();
311   unsigned AlignR = lvalue.getAlignment().getQuantity();
312   ASTContext &C = CGF.getContext();
313   QualType ComplexTy = lvalue.getType();
314   unsigned ComplexAlign = C.getTypeAlignInChars(ComplexTy).getQuantity();
315   unsigned AlignI = std::min(AlignR, ComplexAlign);
316 
317   llvm::Value *Real=nullptr, *Imag=nullptr;
318 
319   if (!IgnoreReal || isVolatile) {
320     llvm::Value *RealP = Builder.CreateStructGEP(SrcPtr, 0,
321                                                  SrcPtr->getName() + ".realp");
322     Real = Builder.CreateAlignedLoad(RealP, AlignR, isVolatile,
323                                      SrcPtr->getName() + ".real");
324   }
325 
326   if (!IgnoreImag || isVolatile) {
327     llvm::Value *ImagP = Builder.CreateStructGEP(SrcPtr, 1,
328                                                  SrcPtr->getName() + ".imagp");
329     Imag = Builder.CreateAlignedLoad(ImagP, AlignI, isVolatile,
330                                      SrcPtr->getName() + ".imag");
331   }
332   return ComplexPairTy(Real, Imag);
333 }
334 
335 /// EmitStoreOfComplex - Store the specified real/imag parts into the
336 /// specified value pointer.
337 void ComplexExprEmitter::EmitStoreOfComplex(ComplexPairTy Val, LValue lvalue,
338                                             bool isInit) {
339   if (lvalue.getType()->isAtomicType())
340     return CGF.EmitAtomicStore(RValue::getComplex(Val), lvalue, isInit);
341 
342   llvm::Value *Ptr = lvalue.getAddress();
343   llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, "real");
344   llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, "imag");
345   unsigned AlignR = lvalue.getAlignment().getQuantity();
346   ASTContext &C = CGF.getContext();
347   QualType ComplexTy = lvalue.getType();
348   unsigned ComplexAlign = C.getTypeAlignInChars(ComplexTy).getQuantity();
349   unsigned AlignI = std::min(AlignR, ComplexAlign);
350 
351   Builder.CreateAlignedStore(Val.first, RealPtr, AlignR,
352                              lvalue.isVolatileQualified());
353   Builder.CreateAlignedStore(Val.second, ImagPtr, AlignI,
354                              lvalue.isVolatileQualified());
355 }
356 
357 
358 
359 //===----------------------------------------------------------------------===//
360 //                            Visitor Methods
361 //===----------------------------------------------------------------------===//
362 
363 ComplexPairTy ComplexExprEmitter::VisitExpr(Expr *E) {
364   CGF.ErrorUnsupported(E, "complex expression");
365   llvm::Type *EltTy =
366     CGF.ConvertType(getComplexType(E->getType())->getElementType());
367   llvm::Value *U = llvm::UndefValue::get(EltTy);
368   return ComplexPairTy(U, U);
369 }
370 
371 ComplexPairTy ComplexExprEmitter::
372 VisitImaginaryLiteral(const ImaginaryLiteral *IL) {
373   llvm::Value *Imag = CGF.EmitScalarExpr(IL->getSubExpr());
374   return ComplexPairTy(llvm::Constant::getNullValue(Imag->getType()), Imag);
375 }
376 
377 
378 ComplexPairTy ComplexExprEmitter::VisitCallExpr(const CallExpr *E) {
379   if (E->getCallReturnType()->isReferenceType())
380     return EmitLoadOfLValue(E);
381 
382   return CGF.EmitCallExpr(E).getComplexVal();
383 }
384 
385 ComplexPairTy ComplexExprEmitter::VisitStmtExpr(const StmtExpr *E) {
386   CodeGenFunction::StmtExprEvaluation eval(CGF);
387   llvm::Value *RetAlloca = CGF.EmitCompoundStmt(*E->getSubStmt(), true);
388   assert(RetAlloca && "Expected complex return value");
389   return EmitLoadOfLValue(CGF.MakeAddrLValue(RetAlloca, E->getType()),
390                           E->getExprLoc());
391 }
392 
393 /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
394 ComplexPairTy ComplexExprEmitter::EmitComplexToComplexCast(ComplexPairTy Val,
395                                                            QualType SrcType,
396                                                            QualType DestType) {
397   // Get the src/dest element type.
398   SrcType = SrcType->castAs<ComplexType>()->getElementType();
399   DestType = DestType->castAs<ComplexType>()->getElementType();
400 
401   // C99 6.3.1.6: When a value of complex type is converted to another
402   // complex type, both the real and imaginary parts follow the conversion
403   // rules for the corresponding real types.
404   Val.first = CGF.EmitScalarConversion(Val.first, SrcType, DestType);
405   Val.second = CGF.EmitScalarConversion(Val.second, SrcType, DestType);
406   return Val;
407 }
408 
409 ComplexPairTy ComplexExprEmitter::EmitScalarToComplexCast(llvm::Value *Val,
410                                                           QualType SrcType,
411                                                           QualType DestType) {
412   // Convert the input element to the element type of the complex.
413   DestType = DestType->castAs<ComplexType>()->getElementType();
414   Val = CGF.EmitScalarConversion(Val, SrcType, DestType);
415 
416   // Return (realval, 0).
417   return ComplexPairTy(Val, llvm::Constant::getNullValue(Val->getType()));
418 }
419 
420 ComplexPairTy ComplexExprEmitter::EmitCast(CastKind CK, Expr *Op,
421                                            QualType DestTy) {
422   switch (CK) {
423   case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!");
424 
425   // Atomic to non-atomic casts may be more than a no-op for some platforms and
426   // for some types.
427   case CK_AtomicToNonAtomic:
428   case CK_NonAtomicToAtomic:
429   case CK_NoOp:
430   case CK_LValueToRValue:
431   case CK_UserDefinedConversion:
432     return Visit(Op);
433 
434   case CK_LValueBitCast: {
435     LValue origLV = CGF.EmitLValue(Op);
436     llvm::Value *V = origLV.getAddress();
437     V = Builder.CreateBitCast(V,
438                     CGF.ConvertType(CGF.getContext().getPointerType(DestTy)));
439     return EmitLoadOfLValue(CGF.MakeAddrLValue(V, DestTy,
440                                                origLV.getAlignment()),
441                             Op->getExprLoc());
442   }
443 
444   case CK_BitCast:
445   case CK_BaseToDerived:
446   case CK_DerivedToBase:
447   case CK_UncheckedDerivedToBase:
448   case CK_Dynamic:
449   case CK_ToUnion:
450   case CK_ArrayToPointerDecay:
451   case CK_FunctionToPointerDecay:
452   case CK_NullToPointer:
453   case CK_NullToMemberPointer:
454   case CK_BaseToDerivedMemberPointer:
455   case CK_DerivedToBaseMemberPointer:
456   case CK_MemberPointerToBoolean:
457   case CK_ReinterpretMemberPointer:
458   case CK_ConstructorConversion:
459   case CK_IntegralToPointer:
460   case CK_PointerToIntegral:
461   case CK_PointerToBoolean:
462   case CK_ToVoid:
463   case CK_VectorSplat:
464   case CK_IntegralCast:
465   case CK_IntegralToBoolean:
466   case CK_IntegralToFloating:
467   case CK_FloatingToIntegral:
468   case CK_FloatingToBoolean:
469   case CK_FloatingCast:
470   case CK_CPointerToObjCPointerCast:
471   case CK_BlockPointerToObjCPointerCast:
472   case CK_AnyPointerToBlockPointerCast:
473   case CK_ObjCObjectLValueCast:
474   case CK_FloatingComplexToReal:
475   case CK_FloatingComplexToBoolean:
476   case CK_IntegralComplexToReal:
477   case CK_IntegralComplexToBoolean:
478   case CK_ARCProduceObject:
479   case CK_ARCConsumeObject:
480   case CK_ARCReclaimReturnedObject:
481   case CK_ARCExtendBlockObject:
482   case CK_CopyAndAutoreleaseBlockObject:
483   case CK_BuiltinFnToFnPtr:
484   case CK_ZeroToOCLEvent:
485   case CK_AddressSpaceConversion:
486     llvm_unreachable("invalid cast kind for complex value");
487 
488   case CK_FloatingRealToComplex:
489   case CK_IntegralRealToComplex:
490     return EmitScalarToComplexCast(CGF.EmitScalarExpr(Op),
491                                    Op->getType(), DestTy);
492 
493   case CK_FloatingComplexCast:
494   case CK_FloatingComplexToIntegralComplex:
495   case CK_IntegralComplexCast:
496   case CK_IntegralComplexToFloatingComplex:
497     return EmitComplexToComplexCast(Visit(Op), Op->getType(), DestTy);
498   }
499 
500   llvm_unreachable("unknown cast resulting in complex value");
501 }
502 
503 ComplexPairTy ComplexExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
504   TestAndClearIgnoreReal();
505   TestAndClearIgnoreImag();
506   ComplexPairTy Op = Visit(E->getSubExpr());
507 
508   llvm::Value *ResR, *ResI;
509   if (Op.first->getType()->isFloatingPointTy()) {
510     ResR = Builder.CreateFNeg(Op.first,  "neg.r");
511     ResI = Builder.CreateFNeg(Op.second, "neg.i");
512   } else {
513     ResR = Builder.CreateNeg(Op.first,  "neg.r");
514     ResI = Builder.CreateNeg(Op.second, "neg.i");
515   }
516   return ComplexPairTy(ResR, ResI);
517 }
518 
519 ComplexPairTy ComplexExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
520   TestAndClearIgnoreReal();
521   TestAndClearIgnoreImag();
522   // ~(a+ib) = a + i*-b
523   ComplexPairTy Op = Visit(E->getSubExpr());
524   llvm::Value *ResI;
525   if (Op.second->getType()->isFloatingPointTy())
526     ResI = Builder.CreateFNeg(Op.second, "conj.i");
527   else
528     ResI = Builder.CreateNeg(Op.second, "conj.i");
529 
530   return ComplexPairTy(Op.first, ResI);
531 }
532 
533 ComplexPairTy ComplexExprEmitter::EmitBinAdd(const BinOpInfo &Op) {
534   llvm::Value *ResR, *ResI;
535 
536   if (Op.LHS.first->getType()->isFloatingPointTy()) {
537     ResR = Builder.CreateFAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
538     if (Op.LHS.second && Op.RHS.second)
539       ResI = Builder.CreateFAdd(Op.LHS.second, Op.RHS.second, "add.i");
540     else
541       ResI = Op.LHS.second ? Op.LHS.second : Op.RHS.second;
542     assert(ResI && "Only one operand may be real!");
543   } else {
544     ResR = Builder.CreateAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
545     assert(Op.LHS.second && Op.RHS.second &&
546            "Both operands of integer complex operators must be complex!");
547     ResI = Builder.CreateAdd(Op.LHS.second, Op.RHS.second, "add.i");
548   }
549   return ComplexPairTy(ResR, ResI);
550 }
551 
552 ComplexPairTy ComplexExprEmitter::EmitBinSub(const BinOpInfo &Op) {
553   llvm::Value *ResR, *ResI;
554   if (Op.LHS.first->getType()->isFloatingPointTy()) {
555     ResR = Builder.CreateFSub(Op.LHS.first, Op.RHS.first, "sub.r");
556     if (Op.LHS.second && Op.RHS.second)
557       ResI = Builder.CreateFSub(Op.LHS.second, Op.RHS.second, "sub.i");
558     else
559       ResI = Op.LHS.second ? Op.LHS.second
560                            : Builder.CreateFNeg(Op.RHS.second, "sub.i");
561     assert(ResI && "Only one operand may be real!");
562   } else {
563     ResR = Builder.CreateSub(Op.LHS.first, Op.RHS.first, "sub.r");
564     assert(Op.LHS.second && Op.RHS.second &&
565            "Both operands of integer complex operators must be complex!");
566     ResI = Builder.CreateSub(Op.LHS.second, Op.RHS.second, "sub.i");
567   }
568   return ComplexPairTy(ResR, ResI);
569 }
570 
571 /// \brief Emit a libcall for a binary operation on complex types.
572 ComplexPairTy ComplexExprEmitter::EmitComplexBinOpLibCall(StringRef LibCallName,
573                                                           const BinOpInfo &Op) {
574   CallArgList Args;
575   Args.add(RValue::get(Op.LHS.first),
576            Op.Ty->castAs<ComplexType>()->getElementType());
577   Args.add(RValue::get(Op.LHS.second),
578            Op.Ty->castAs<ComplexType>()->getElementType());
579   Args.add(RValue::get(Op.RHS.first),
580            Op.Ty->castAs<ComplexType>()->getElementType());
581   Args.add(RValue::get(Op.RHS.second),
582            Op.Ty->castAs<ComplexType>()->getElementType());
583 
584   // We *must* use the full CG function call building logic here because the
585   // complex type has special ABI handling. We also should not forget about
586   // special calling convention which may be used for compiler builtins.
587   const CGFunctionInfo &FuncInfo =
588     CGF.CGM.getTypes().arrangeFreeFunctionCall(
589       Op.Ty, Args, FunctionType::ExtInfo(/* No CC here - will be added later */),
590       RequiredArgs::All);
591   llvm::FunctionType *FTy = CGF.CGM.getTypes().GetFunctionType(FuncInfo);
592   llvm::Constant *Func = CGF.CGM.CreateBuiltinFunction(FTy, LibCallName);
593   llvm::Instruction *Call;
594 
595   RValue Res = CGF.EmitCall(FuncInfo, Func, ReturnValueSlot(), Args,
596                             nullptr, &Call);
597   cast<llvm::CallInst>(Call)->setCallingConv(CGF.CGM.getBuiltinCC());
598   cast<llvm::CallInst>(Call)->setDoesNotThrow();
599 
600   return Res.getComplexVal();
601 }
602 
603 /// \brief Lookup the libcall name for a given floating point type complex
604 /// multiply.
605 static StringRef getComplexMultiplyLibCallName(llvm::Type *Ty) {
606   switch (Ty->getTypeID()) {
607   default:
608     llvm_unreachable("Unsupported floating point type!");
609   case llvm::Type::HalfTyID:
610     return "__mulhc3";
611   case llvm::Type::FloatTyID:
612     return "__mulsc3";
613   case llvm::Type::DoubleTyID:
614     return "__muldc3";
615   case llvm::Type::PPC_FP128TyID:
616     return "__multc3";
617   case llvm::Type::X86_FP80TyID:
618     return "__mulxc3";
619   case llvm::Type::FP128TyID:
620     return "__multc3";
621   }
622 }
623 
624 // See C11 Annex G.5.1 for the semantics of multiplicative operators on complex
625 // typed values.
626 ComplexPairTy ComplexExprEmitter::EmitBinMul(const BinOpInfo &Op) {
627   using llvm::Value;
628   Value *ResR, *ResI;
629   llvm::MDBuilder MDHelper(CGF.getLLVMContext());
630 
631   if (Op.LHS.first->getType()->isFloatingPointTy()) {
632     // The general formulation is:
633     // (a + ib) * (c + id) = (a * c - b * d) + i(a * d + b * c)
634     //
635     // But we can fold away components which would be zero due to a real
636     // operand according to C11 Annex G.5.1p2.
637     // FIXME: C11 also provides for imaginary types which would allow folding
638     // still more of this within the type system.
639 
640     if (Op.LHS.second && Op.RHS.second) {
641       // If both operands are complex, emit the core math directly, and then
642       // test for NaNs. If we find NaNs in the result, we delegate to a libcall
643       // to carefully re-compute the correct infinity representation if
644       // possible. The expectation is that the presence of NaNs here is
645       // *extremely* rare, and so the cost of the libcall is almost irrelevant.
646       // This is good, because the libcall re-computes the core multiplication
647       // exactly the same as we do here and re-tests for NaNs in order to be
648       // a generic complex*complex libcall.
649 
650       // First compute the four products.
651       Value *AC = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul_ac");
652       Value *BD = Builder.CreateFMul(Op.LHS.second, Op.RHS.second, "mul_bd");
653       Value *AD = Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul_ad");
654       Value *BC = Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul_bc");
655 
656       // The real part is the difference of the first two, the imaginary part is
657       // the sum of the second.
658       ResR = Builder.CreateFSub(AC, BD, "mul_r");
659       ResI = Builder.CreateFAdd(AD, BC, "mul_i");
660 
661       // Emit the test for the real part becoming NaN and create a branch to
662       // handle it. We test for NaN by comparing the number to itself.
663       Value *IsRNaN = Builder.CreateFCmpUNO(ResR, ResR, "isnan_cmp");
664       llvm::BasicBlock *ContBB = CGF.createBasicBlock("complex_mul_cont");
665       llvm::BasicBlock *INaNBB = CGF.createBasicBlock("complex_mul_imag_nan");
666       llvm::Instruction *Branch = Builder.CreateCondBr(IsRNaN, INaNBB, ContBB);
667       llvm::BasicBlock *OrigBB = Branch->getParent();
668 
669       // Give hint that we very much don't expect to see NaNs.
670       // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
671       llvm::MDNode *BrWeight = MDHelper.createBranchWeights(1, (1U << 20) - 1);
672       Branch->setMetadata(llvm::LLVMContext::MD_prof, BrWeight);
673 
674       // Now test the imaginary part and create its branch.
675       CGF.EmitBlock(INaNBB);
676       Value *IsINaN = Builder.CreateFCmpUNO(ResI, ResI, "isnan_cmp");
677       llvm::BasicBlock *LibCallBB = CGF.createBasicBlock("complex_mul_libcall");
678       Branch = Builder.CreateCondBr(IsINaN, LibCallBB, ContBB);
679       Branch->setMetadata(llvm::LLVMContext::MD_prof, BrWeight);
680 
681       // Now emit the libcall on this slowest of the slow paths.
682       CGF.EmitBlock(LibCallBB);
683       Value *LibCallR, *LibCallI;
684       std::tie(LibCallR, LibCallI) = EmitComplexBinOpLibCall(
685           getComplexMultiplyLibCallName(Op.LHS.first->getType()), Op);
686       Builder.CreateBr(ContBB);
687 
688       // Finally continue execution by phi-ing together the different
689       // computation paths.
690       CGF.EmitBlock(ContBB);
691       llvm::PHINode *RealPHI = Builder.CreatePHI(ResR->getType(), 3, "real_mul_phi");
692       RealPHI->addIncoming(ResR, OrigBB);
693       RealPHI->addIncoming(ResR, INaNBB);
694       RealPHI->addIncoming(LibCallR, LibCallBB);
695       llvm::PHINode *ImagPHI = Builder.CreatePHI(ResI->getType(), 3, "imag_mul_phi");
696       ImagPHI->addIncoming(ResI, OrigBB);
697       ImagPHI->addIncoming(ResI, INaNBB);
698       ImagPHI->addIncoming(LibCallI, LibCallBB);
699       return ComplexPairTy(RealPHI, ImagPHI);
700     }
701     assert((Op.LHS.second || Op.RHS.second) &&
702            "At least one operand must be complex!");
703 
704     // If either of the operands is a real rather than a complex, the
705     // imaginary component is ignored when computing the real component of the
706     // result.
707     ResR = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul.rl");
708 
709     ResI = Op.LHS.second
710                ? Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul.il")
711                : Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul.ir");
712   } else {
713     assert(Op.LHS.second && Op.RHS.second &&
714            "Both operands of integer complex operators must be complex!");
715     Value *ResRl = Builder.CreateMul(Op.LHS.first, Op.RHS.first, "mul.rl");
716     Value *ResRr = Builder.CreateMul(Op.LHS.second, Op.RHS.second, "mul.rr");
717     ResR = Builder.CreateSub(ResRl, ResRr, "mul.r");
718 
719     Value *ResIl = Builder.CreateMul(Op.LHS.second, Op.RHS.first, "mul.il");
720     Value *ResIr = Builder.CreateMul(Op.LHS.first, Op.RHS.second, "mul.ir");
721     ResI = Builder.CreateAdd(ResIl, ResIr, "mul.i");
722   }
723   return ComplexPairTy(ResR, ResI);
724 }
725 
726 // See C11 Annex G.5.1 for the semantics of multiplicative operators on complex
727 // typed values.
728 ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
729   llvm::Value *LHSr = Op.LHS.first, *LHSi = Op.LHS.second;
730   llvm::Value *RHSr = Op.RHS.first, *RHSi = Op.RHS.second;
731 
732 
733   llvm::Value *DSTr, *DSTi;
734   if (LHSr->getType()->isFloatingPointTy()) {
735     // If we have a complex operand on the RHS, we delegate to a libcall to
736     // handle all of the complexities and minimize underflow/overflow cases.
737     //
738     // FIXME: We would be able to avoid the libcall in many places if we
739     // supported imaginary types in addition to complex types.
740     if (RHSi) {
741       BinOpInfo LibCallOp = Op;
742       // If LHS was a real, supply a null imaginary part.
743       if (!LHSi)
744         LibCallOp.LHS.second = llvm::Constant::getNullValue(LHSr->getType());
745 
746       StringRef LibCallName;
747       switch (LHSr->getType()->getTypeID()) {
748       default:
749         llvm_unreachable("Unsupported floating point type!");
750       case llvm::Type::HalfTyID:
751         return EmitComplexBinOpLibCall("__divhc3", LibCallOp);
752       case llvm::Type::FloatTyID:
753         return EmitComplexBinOpLibCall("__divsc3", LibCallOp);
754       case llvm::Type::DoubleTyID:
755         return EmitComplexBinOpLibCall("__divdc3", LibCallOp);
756       case llvm::Type::PPC_FP128TyID:
757         return EmitComplexBinOpLibCall("__divtc3", LibCallOp);
758       case llvm::Type::X86_FP80TyID:
759         return EmitComplexBinOpLibCall("__divxc3", LibCallOp);
760       case llvm::Type::FP128TyID:
761         return EmitComplexBinOpLibCall("__divtc3", LibCallOp);
762       }
763     }
764     assert(LHSi && "Can have at most one non-complex operand!");
765 
766     DSTr = Builder.CreateFDiv(LHSr, RHSr);
767     DSTi = Builder.CreateFDiv(LHSi, RHSr);
768   } else {
769     assert(Op.LHS.second && Op.RHS.second &&
770            "Both operands of integer complex operators must be complex!");
771     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
772     llvm::Value *Tmp1 = Builder.CreateMul(LHSr, RHSr); // a*c
773     llvm::Value *Tmp2 = Builder.CreateMul(LHSi, RHSi); // b*d
774     llvm::Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2); // ac+bd
775 
776     llvm::Value *Tmp4 = Builder.CreateMul(RHSr, RHSr); // c*c
777     llvm::Value *Tmp5 = Builder.CreateMul(RHSi, RHSi); // d*d
778     llvm::Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5); // cc+dd
779 
780     llvm::Value *Tmp7 = Builder.CreateMul(LHSi, RHSr); // b*c
781     llvm::Value *Tmp8 = Builder.CreateMul(LHSr, RHSi); // a*d
782     llvm::Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8); // bc-ad
783 
784     if (Op.Ty->castAs<ComplexType>()->getElementType()->isUnsignedIntegerType()) {
785       DSTr = Builder.CreateUDiv(Tmp3, Tmp6);
786       DSTi = Builder.CreateUDiv(Tmp9, Tmp6);
787     } else {
788       DSTr = Builder.CreateSDiv(Tmp3, Tmp6);
789       DSTi = Builder.CreateSDiv(Tmp9, Tmp6);
790     }
791   }
792 
793   return ComplexPairTy(DSTr, DSTi);
794 }
795 
796 ComplexExprEmitter::BinOpInfo
797 ComplexExprEmitter::EmitBinOps(const BinaryOperator *E) {
798   TestAndClearIgnoreReal();
799   TestAndClearIgnoreImag();
800   BinOpInfo Ops;
801   if (E->getLHS()->getType()->isRealFloatingType())
802     Ops.LHS = ComplexPairTy(CGF.EmitScalarExpr(E->getLHS()), nullptr);
803   else
804     Ops.LHS = Visit(E->getLHS());
805   if (E->getRHS()->getType()->isRealFloatingType())
806     Ops.RHS = ComplexPairTy(CGF.EmitScalarExpr(E->getRHS()), nullptr);
807   else
808     Ops.RHS = Visit(E->getRHS());
809 
810   Ops.Ty = E->getType();
811   return Ops;
812 }
813 
814 
815 LValue ComplexExprEmitter::
816 EmitCompoundAssignLValue(const CompoundAssignOperator *E,
817           ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&),
818                          RValue &Val) {
819   TestAndClearIgnoreReal();
820   TestAndClearIgnoreImag();
821   QualType LHSTy = E->getLHS()->getType();
822 
823   BinOpInfo OpInfo;
824 
825   // Load the RHS and LHS operands.
826   // __block variables need to have the rhs evaluated first, plus this should
827   // improve codegen a little.
828   OpInfo.Ty = E->getComputationResultType();
829   QualType ComplexElementTy = cast<ComplexType>(OpInfo.Ty)->getElementType();
830 
831   // The RHS should have been converted to the computation type.
832   if (E->getRHS()->getType()->isRealFloatingType()) {
833     assert(
834         CGF.getContext()
835             .hasSameUnqualifiedType(ComplexElementTy, E->getRHS()->getType()));
836     OpInfo.RHS = ComplexPairTy(CGF.EmitScalarExpr(E->getRHS()), nullptr);
837   } else {
838     assert(CGF.getContext()
839                .hasSameUnqualifiedType(OpInfo.Ty, E->getRHS()->getType()));
840     OpInfo.RHS = Visit(E->getRHS());
841   }
842 
843   LValue LHS = CGF.EmitLValue(E->getLHS());
844 
845   // Load from the l-value and convert it.
846   if (LHSTy->isAnyComplexType()) {
847     ComplexPairTy LHSVal = EmitLoadOfLValue(LHS, E->getExprLoc());
848     OpInfo.LHS = EmitComplexToComplexCast(LHSVal, LHSTy, OpInfo.Ty);
849   } else {
850     llvm::Value *LHSVal = CGF.EmitLoadOfScalar(LHS, E->getExprLoc());
851     // For floating point real operands we can directly pass the scalar form
852     // to the binary operator emission and potentially get more efficient code.
853     if (LHSTy->isRealFloatingType()) {
854       if (!CGF.getContext().hasSameUnqualifiedType(ComplexElementTy, LHSTy))
855         LHSVal = CGF.EmitScalarConversion(LHSVal, LHSTy, ComplexElementTy);
856       OpInfo.LHS = ComplexPairTy(LHSVal, nullptr);
857     } else {
858       OpInfo.LHS = EmitScalarToComplexCast(LHSVal, LHSTy, OpInfo.Ty);
859     }
860   }
861 
862   // Expand the binary operator.
863   ComplexPairTy Result = (this->*Func)(OpInfo);
864 
865   // Truncate the result and store it into the LHS lvalue.
866   if (LHSTy->isAnyComplexType()) {
867     ComplexPairTy ResVal = EmitComplexToComplexCast(Result, OpInfo.Ty, LHSTy);
868     EmitStoreOfComplex(ResVal, LHS, /*isInit*/ false);
869     Val = RValue::getComplex(ResVal);
870   } else {
871     llvm::Value *ResVal =
872         CGF.EmitComplexToScalarConversion(Result, OpInfo.Ty, LHSTy);
873     CGF.EmitStoreOfScalar(ResVal, LHS, /*isInit*/ false);
874     Val = RValue::get(ResVal);
875   }
876 
877   return LHS;
878 }
879 
880 // Compound assignments.
881 ComplexPairTy ComplexExprEmitter::
882 EmitCompoundAssign(const CompoundAssignOperator *E,
883                    ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&)){
884   RValue Val;
885   LValue LV = EmitCompoundAssignLValue(E, Func, Val);
886 
887   // The result of an assignment in C is the assigned r-value.
888   if (!CGF.getLangOpts().CPlusPlus)
889     return Val.getComplexVal();
890 
891   // If the lvalue is non-volatile, return the computed value of the assignment.
892   if (!LV.isVolatileQualified())
893     return Val.getComplexVal();
894 
895   return EmitLoadOfLValue(LV, E->getExprLoc());
896 }
897 
898 LValue ComplexExprEmitter::EmitBinAssignLValue(const BinaryOperator *E,
899                                                ComplexPairTy &Val) {
900   assert(CGF.getContext().hasSameUnqualifiedType(E->getLHS()->getType(),
901                                                  E->getRHS()->getType()) &&
902          "Invalid assignment");
903   TestAndClearIgnoreReal();
904   TestAndClearIgnoreImag();
905 
906   // Emit the RHS.  __block variables need the RHS evaluated first.
907   Val = Visit(E->getRHS());
908 
909   // Compute the address to store into.
910   LValue LHS = CGF.EmitLValue(E->getLHS());
911 
912   // Store the result value into the LHS lvalue.
913   EmitStoreOfComplex(Val, LHS, /*isInit*/ false);
914 
915   return LHS;
916 }
917 
918 ComplexPairTy ComplexExprEmitter::VisitBinAssign(const BinaryOperator *E) {
919   ComplexPairTy Val;
920   LValue LV = EmitBinAssignLValue(E, Val);
921 
922   // The result of an assignment in C is the assigned r-value.
923   if (!CGF.getLangOpts().CPlusPlus)
924     return Val;
925 
926   // If the lvalue is non-volatile, return the computed value of the assignment.
927   if (!LV.isVolatileQualified())
928     return Val;
929 
930   return EmitLoadOfLValue(LV, E->getExprLoc());
931 }
932 
933 ComplexPairTy ComplexExprEmitter::VisitBinComma(const BinaryOperator *E) {
934   CGF.EmitIgnoredExpr(E->getLHS());
935   return Visit(E->getRHS());
936 }
937 
938 ComplexPairTy ComplexExprEmitter::
939 VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) {
940   TestAndClearIgnoreReal();
941   TestAndClearIgnoreImag();
942   llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
943   llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
944   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
945 
946   // Bind the common expression if necessary.
947   CodeGenFunction::OpaqueValueMapping binding(CGF, E);
948 
949   RegionCounter Cnt = CGF.getPGORegionCounter(E);
950   CodeGenFunction::ConditionalEvaluation eval(CGF);
951   CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock, Cnt.getCount());
952 
953   eval.begin(CGF);
954   CGF.EmitBlock(LHSBlock);
955   Cnt.beginRegion(Builder);
956   ComplexPairTy LHS = Visit(E->getTrueExpr());
957   LHSBlock = Builder.GetInsertBlock();
958   CGF.EmitBranch(ContBlock);
959   eval.end(CGF);
960 
961   eval.begin(CGF);
962   CGF.EmitBlock(RHSBlock);
963   ComplexPairTy RHS = Visit(E->getFalseExpr());
964   RHSBlock = Builder.GetInsertBlock();
965   CGF.EmitBlock(ContBlock);
966   eval.end(CGF);
967 
968   // Create a PHI node for the real part.
969   llvm::PHINode *RealPN = Builder.CreatePHI(LHS.first->getType(), 2, "cond.r");
970   RealPN->addIncoming(LHS.first, LHSBlock);
971   RealPN->addIncoming(RHS.first, RHSBlock);
972 
973   // Create a PHI node for the imaginary part.
974   llvm::PHINode *ImagPN = Builder.CreatePHI(LHS.first->getType(), 2, "cond.i");
975   ImagPN->addIncoming(LHS.second, LHSBlock);
976   ImagPN->addIncoming(RHS.second, RHSBlock);
977 
978   return ComplexPairTy(RealPN, ImagPN);
979 }
980 
981 ComplexPairTy ComplexExprEmitter::VisitChooseExpr(ChooseExpr *E) {
982   return Visit(E->getChosenSubExpr());
983 }
984 
985 ComplexPairTy ComplexExprEmitter::VisitInitListExpr(InitListExpr *E) {
986     bool Ignore = TestAndClearIgnoreReal();
987     (void)Ignore;
988     assert (Ignore == false && "init list ignored");
989     Ignore = TestAndClearIgnoreImag();
990     (void)Ignore;
991     assert (Ignore == false && "init list ignored");
992 
993   if (E->getNumInits() == 2) {
994     llvm::Value *Real = CGF.EmitScalarExpr(E->getInit(0));
995     llvm::Value *Imag = CGF.EmitScalarExpr(E->getInit(1));
996     return ComplexPairTy(Real, Imag);
997   } else if (E->getNumInits() == 1) {
998     return Visit(E->getInit(0));
999   }
1000 
1001   // Empty init list intializes to null
1002   assert(E->getNumInits() == 0 && "Unexpected number of inits");
1003   QualType Ty = E->getType()->castAs<ComplexType>()->getElementType();
1004   llvm::Type* LTy = CGF.ConvertType(Ty);
1005   llvm::Value* zeroConstant = llvm::Constant::getNullValue(LTy);
1006   return ComplexPairTy(zeroConstant, zeroConstant);
1007 }
1008 
1009 ComplexPairTy ComplexExprEmitter::VisitVAArgExpr(VAArgExpr *E) {
1010   llvm::Value *ArgValue = CGF.EmitVAListRef(E->getSubExpr());
1011   llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, E->getType());
1012 
1013   if (!ArgPtr) {
1014     CGF.ErrorUnsupported(E, "complex va_arg expression");
1015     llvm::Type *EltTy =
1016       CGF.ConvertType(E->getType()->castAs<ComplexType>()->getElementType());
1017     llvm::Value *U = llvm::UndefValue::get(EltTy);
1018     return ComplexPairTy(U, U);
1019   }
1020 
1021   return EmitLoadOfLValue(CGF.MakeNaturalAlignAddrLValue(ArgPtr, E->getType()),
1022                           E->getExprLoc());
1023 }
1024 
1025 //===----------------------------------------------------------------------===//
1026 //                         Entry Point into this File
1027 //===----------------------------------------------------------------------===//
1028 
1029 /// EmitComplexExpr - Emit the computation of the specified expression of
1030 /// complex type, ignoring the result.
1031 ComplexPairTy CodeGenFunction::EmitComplexExpr(const Expr *E, bool IgnoreReal,
1032                                                bool IgnoreImag) {
1033   assert(E && getComplexType(E->getType()) &&
1034          "Invalid complex expression to emit");
1035 
1036   return ComplexExprEmitter(*this, IgnoreReal, IgnoreImag)
1037     .Visit(const_cast<Expr*>(E));
1038 }
1039 
1040 void CodeGenFunction::EmitComplexExprIntoLValue(const Expr *E, LValue dest,
1041                                                 bool isInit) {
1042   assert(E && getComplexType(E->getType()) &&
1043          "Invalid complex expression to emit");
1044   ComplexExprEmitter Emitter(*this);
1045   ComplexPairTy Val = Emitter.Visit(const_cast<Expr*>(E));
1046   Emitter.EmitStoreOfComplex(Val, dest, isInit);
1047 }
1048 
1049 /// EmitStoreOfComplex - Store a complex number into the specified l-value.
1050 void CodeGenFunction::EmitStoreOfComplex(ComplexPairTy V, LValue dest,
1051                                          bool isInit) {
1052   ComplexExprEmitter(*this).EmitStoreOfComplex(V, dest, isInit);
1053 }
1054 
1055 /// EmitLoadOfComplex - Load a complex number from the specified address.
1056 ComplexPairTy CodeGenFunction::EmitLoadOfComplex(LValue src,
1057                                                  SourceLocation loc) {
1058   return ComplexExprEmitter(*this).EmitLoadOfLValue(src, loc);
1059 }
1060 
1061 LValue CodeGenFunction::EmitComplexAssignmentLValue(const BinaryOperator *E) {
1062   assert(E->getOpcode() == BO_Assign);
1063   ComplexPairTy Val; // ignored
1064   return ComplexExprEmitter(*this).EmitBinAssignLValue(E, Val);
1065 }
1066 
1067 typedef ComplexPairTy (ComplexExprEmitter::*CompoundFunc)(
1068     const ComplexExprEmitter::BinOpInfo &);
1069 
1070 static CompoundFunc getComplexOp(BinaryOperatorKind Op) {
1071   switch (Op) {
1072   case BO_MulAssign: return &ComplexExprEmitter::EmitBinMul;
1073   case BO_DivAssign: return &ComplexExprEmitter::EmitBinDiv;
1074   case BO_SubAssign: return &ComplexExprEmitter::EmitBinSub;
1075   case BO_AddAssign: return &ComplexExprEmitter::EmitBinAdd;
1076   default:
1077     llvm_unreachable("unexpected complex compound assignment");
1078   }
1079 }
1080 
1081 LValue CodeGenFunction::
1082 EmitComplexCompoundAssignmentLValue(const CompoundAssignOperator *E) {
1083   CompoundFunc Op = getComplexOp(E->getOpcode());
1084   RValue Val;
1085   return ComplexExprEmitter(*this).EmitCompoundAssignLValue(E, Op, Val);
1086 }
1087 
1088 LValue CodeGenFunction::
1089 EmitScalarCompooundAssignWithComplex(const CompoundAssignOperator *E,
1090                                      llvm::Value *&Result) {
1091   CompoundFunc Op = getComplexOp(E->getOpcode());
1092   RValue Val;
1093   LValue Ret = ComplexExprEmitter(*this).EmitCompoundAssignLValue(E, Op, Val);
1094   Result = Val.getScalarVal();
1095   return Ret;
1096 }
1097