1 //===--- CGExprComplex.cpp - Emit LLVM Code for Complex Exprs -------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This contains code to emit Expr nodes with complex types as LLVM code.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "CGOpenMPRuntime.h"
14 #include "CodeGenFunction.h"
15 #include "CodeGenModule.h"
16 #include "clang/AST/StmtVisitor.h"
17 #include "llvm/ADT/STLExtras.h"
18 #include "llvm/IR/Constants.h"
19 #include "llvm/IR/Instructions.h"
20 #include "llvm/IR/MDBuilder.h"
21 #include "llvm/IR/Metadata.h"
22 #include <algorithm>
23 using namespace clang;
24 using namespace CodeGen;
25 
26 //===----------------------------------------------------------------------===//
27 //                        Complex Expression Emitter
28 //===----------------------------------------------------------------------===//
29 
30 typedef CodeGenFunction::ComplexPairTy ComplexPairTy;
31 
32 /// Return the complex type that we are meant to emit.
33 static const ComplexType *getComplexType(QualType type) {
34   type = type.getCanonicalType();
35   if (const ComplexType *comp = dyn_cast<ComplexType>(type)) {
36     return comp;
37   } else {
38     return cast<ComplexType>(cast<AtomicType>(type)->getValueType());
39   }
40 }
41 
42 namespace  {
43 class ComplexExprEmitter
44   : public StmtVisitor<ComplexExprEmitter, ComplexPairTy> {
45   CodeGenFunction &CGF;
46   CGBuilderTy &Builder;
47   bool IgnoreReal;
48   bool IgnoreImag;
49 public:
50   ComplexExprEmitter(CodeGenFunction &cgf, bool ir=false, bool ii=false)
51     : CGF(cgf), Builder(CGF.Builder), IgnoreReal(ir), IgnoreImag(ii) {
52   }
53 
54 
55   //===--------------------------------------------------------------------===//
56   //                               Utilities
57   //===--------------------------------------------------------------------===//
58 
59   bool TestAndClearIgnoreReal() {
60     bool I = IgnoreReal;
61     IgnoreReal = false;
62     return I;
63   }
64   bool TestAndClearIgnoreImag() {
65     bool I = IgnoreImag;
66     IgnoreImag = false;
67     return I;
68   }
69 
70   /// EmitLoadOfLValue - Given an expression with complex type that represents a
71   /// value l-value, this method emits the address of the l-value, then loads
72   /// and returns the result.
73   ComplexPairTy EmitLoadOfLValue(const Expr *E) {
74     return EmitLoadOfLValue(CGF.EmitLValue(E), E->getExprLoc());
75   }
76 
77   ComplexPairTy EmitLoadOfLValue(LValue LV, SourceLocation Loc);
78 
79   /// EmitStoreOfComplex - Store the specified real/imag parts into the
80   /// specified value pointer.
81   void EmitStoreOfComplex(ComplexPairTy Val, LValue LV, bool isInit);
82 
83   /// Emit a cast from complex value Val to DestType.
84   ComplexPairTy EmitComplexToComplexCast(ComplexPairTy Val, QualType SrcType,
85                                          QualType DestType, SourceLocation Loc);
86   /// Emit a cast from scalar value Val to DestType.
87   ComplexPairTy EmitScalarToComplexCast(llvm::Value *Val, QualType SrcType,
88                                         QualType DestType, SourceLocation Loc);
89 
90   //===--------------------------------------------------------------------===//
91   //                            Visitor Methods
92   //===--------------------------------------------------------------------===//
93 
94   ComplexPairTy Visit(Expr *E) {
95     ApplyDebugLocation DL(CGF, E);
96     return StmtVisitor<ComplexExprEmitter, ComplexPairTy>::Visit(E);
97   }
98 
99   ComplexPairTy VisitStmt(Stmt *S) {
100     S->dump(CGF.getContext().getSourceManager());
101     llvm_unreachable("Stmt can't have complex result type!");
102   }
103   ComplexPairTy VisitExpr(Expr *S);
104   ComplexPairTy VisitConstantExpr(ConstantExpr *E) {
105     return Visit(E->getSubExpr());
106   }
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   ComplexPairTy VisitCoawaitExpr(CoawaitExpr *S) {
117     return CGF.EmitCoawaitExpr(*S).getComplexVal();
118   }
119   ComplexPairTy VisitCoyieldExpr(CoyieldExpr *S) {
120     return CGF.EmitCoyieldExpr(*S).getComplexVal();
121   }
122   ComplexPairTy VisitUnaryCoawait(const UnaryOperator *E) {
123     return Visit(E->getSubExpr());
124   }
125 
126   ComplexPairTy emitConstant(const CodeGenFunction::ConstantEmission &Constant,
127                              Expr *E) {
128     assert(Constant && "not a constant");
129     if (Constant.isReference())
130       return EmitLoadOfLValue(Constant.getReferenceLValue(CGF, E),
131                               E->getExprLoc());
132 
133     llvm::Constant *pair = Constant.getValue();
134     return ComplexPairTy(pair->getAggregateElement(0U),
135                          pair->getAggregateElement(1U));
136   }
137 
138   // l-values.
139   ComplexPairTy VisitDeclRefExpr(DeclRefExpr *E) {
140     if (CodeGenFunction::ConstantEmission Constant = CGF.tryEmitAsConstant(E))
141       return emitConstant(Constant, E);
142     return EmitLoadOfLValue(E);
143   }
144   ComplexPairTy VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
145     return EmitLoadOfLValue(E);
146   }
147   ComplexPairTy VisitObjCMessageExpr(ObjCMessageExpr *E) {
148     return CGF.EmitObjCMessageExpr(E).getComplexVal();
149   }
150   ComplexPairTy VisitArraySubscriptExpr(Expr *E) { return EmitLoadOfLValue(E); }
151   ComplexPairTy VisitMemberExpr(MemberExpr *ME) {
152     if (CodeGenFunction::ConstantEmission Constant =
153             CGF.tryEmitAsConstant(ME)) {
154       CGF.EmitIgnoredExpr(ME->getBase());
155       return emitConstant(Constant, ME);
156     }
157     return EmitLoadOfLValue(ME);
158   }
159   ComplexPairTy VisitOpaqueValueExpr(OpaqueValueExpr *E) {
160     if (E->isGLValue())
161       return EmitLoadOfLValue(CGF.getOrCreateOpaqueLValueMapping(E),
162                               E->getExprLoc());
163     return CGF.getOrCreateOpaqueRValueMapping(E).getComplexVal();
164   }
165 
166   ComplexPairTy VisitPseudoObjectExpr(PseudoObjectExpr *E) {
167     return CGF.EmitPseudoObjectRValue(E).getComplexVal();
168   }
169 
170   // FIXME: CompoundLiteralExpr
171 
172   ComplexPairTy EmitCast(CastKind CK, Expr *Op, QualType DestTy);
173   ComplexPairTy VisitImplicitCastExpr(ImplicitCastExpr *E) {
174     // Unlike for scalars, we don't have to worry about function->ptr demotion
175     // here.
176     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
177   }
178   ComplexPairTy VisitCastExpr(CastExpr *E) {
179     if (const auto *ECE = dyn_cast<ExplicitCastExpr>(E))
180       CGF.CGM.EmitExplicitCastExprType(ECE, &CGF);
181     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
182   }
183   ComplexPairTy VisitCallExpr(const CallExpr *E);
184   ComplexPairTy VisitStmtExpr(const StmtExpr *E);
185 
186   // Operators.
187   ComplexPairTy VisitPrePostIncDec(const UnaryOperator *E,
188                                    bool isInc, bool isPre) {
189     LValue LV = CGF.EmitLValue(E->getSubExpr());
190     return CGF.EmitComplexPrePostIncDec(E, LV, isInc, isPre);
191   }
192   ComplexPairTy VisitUnaryPostDec(const UnaryOperator *E) {
193     return VisitPrePostIncDec(E, false, false);
194   }
195   ComplexPairTy VisitUnaryPostInc(const UnaryOperator *E) {
196     return VisitPrePostIncDec(E, true, false);
197   }
198   ComplexPairTy VisitUnaryPreDec(const UnaryOperator *E) {
199     return VisitPrePostIncDec(E, false, true);
200   }
201   ComplexPairTy VisitUnaryPreInc(const UnaryOperator *E) {
202     return VisitPrePostIncDec(E, true, true);
203   }
204   ComplexPairTy VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); }
205   ComplexPairTy VisitUnaryPlus     (const UnaryOperator *E) {
206     TestAndClearIgnoreReal();
207     TestAndClearIgnoreImag();
208     return Visit(E->getSubExpr());
209   }
210   ComplexPairTy VisitUnaryMinus    (const UnaryOperator *E);
211   ComplexPairTy VisitUnaryNot      (const UnaryOperator *E);
212   // LNot,Real,Imag never return complex.
213   ComplexPairTy VisitUnaryExtension(const UnaryOperator *E) {
214     return Visit(E->getSubExpr());
215   }
216   ComplexPairTy VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
217     CodeGenFunction::CXXDefaultArgExprScope Scope(CGF, DAE);
218     return Visit(DAE->getExpr());
219   }
220   ComplexPairTy VisitCXXDefaultInitExpr(CXXDefaultInitExpr *DIE) {
221     CodeGenFunction::CXXDefaultInitExprScope Scope(CGF, DIE);
222     return Visit(DIE->getExpr());
223   }
224   ComplexPairTy VisitExprWithCleanups(ExprWithCleanups *E) {
225     CGF.enterFullExpression(E);
226     CodeGenFunction::RunCleanupsScope Scope(CGF);
227     ComplexPairTy Vals = Visit(E->getSubExpr());
228     // Defend against dominance problems caused by jumps out of expression
229     // evaluation through the shared cleanup block.
230     Scope.ForceCleanup({&Vals.first, &Vals.second});
231     return Vals;
232   }
233   ComplexPairTy VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E) {
234     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
235     QualType Elem = E->getType()->castAs<ComplexType>()->getElementType();
236     llvm::Constant *Null = llvm::Constant::getNullValue(CGF.ConvertType(Elem));
237     return ComplexPairTy(Null, Null);
238   }
239   ComplexPairTy VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
240     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
241     QualType Elem = E->getType()->castAs<ComplexType>()->getElementType();
242     llvm::Constant *Null =
243                        llvm::Constant::getNullValue(CGF.ConvertType(Elem));
244     return ComplexPairTy(Null, Null);
245   }
246 
247   struct BinOpInfo {
248     ComplexPairTy LHS;
249     ComplexPairTy RHS;
250     QualType Ty;  // Computation Type.
251   };
252 
253   BinOpInfo EmitBinOps(const BinaryOperator *E);
254   LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E,
255                                   ComplexPairTy (ComplexExprEmitter::*Func)
256                                   (const BinOpInfo &),
257                                   RValue &Val);
258   ComplexPairTy EmitCompoundAssign(const CompoundAssignOperator *E,
259                                    ComplexPairTy (ComplexExprEmitter::*Func)
260                                    (const BinOpInfo &));
261 
262   ComplexPairTy EmitBinAdd(const BinOpInfo &Op);
263   ComplexPairTy EmitBinSub(const BinOpInfo &Op);
264   ComplexPairTy EmitBinMul(const BinOpInfo &Op);
265   ComplexPairTy EmitBinDiv(const BinOpInfo &Op);
266 
267   ComplexPairTy EmitComplexBinOpLibCall(StringRef LibCallName,
268                                         const BinOpInfo &Op);
269 
270   ComplexPairTy VisitBinAdd(const BinaryOperator *E) {
271     return EmitBinAdd(EmitBinOps(E));
272   }
273   ComplexPairTy VisitBinSub(const BinaryOperator *E) {
274     return EmitBinSub(EmitBinOps(E));
275   }
276   ComplexPairTy VisitBinMul(const BinaryOperator *E) {
277     return EmitBinMul(EmitBinOps(E));
278   }
279   ComplexPairTy VisitBinDiv(const BinaryOperator *E) {
280     return EmitBinDiv(EmitBinOps(E));
281   }
282 
283   ComplexPairTy VisitCXXRewrittenBinaryOperator(CXXRewrittenBinaryOperator *E) {
284     return Visit(E->getSemanticForm());
285   }
286 
287   // Compound assignments.
288   ComplexPairTy VisitBinAddAssign(const CompoundAssignOperator *E) {
289     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinAdd);
290   }
291   ComplexPairTy VisitBinSubAssign(const CompoundAssignOperator *E) {
292     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinSub);
293   }
294   ComplexPairTy VisitBinMulAssign(const CompoundAssignOperator *E) {
295     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinMul);
296   }
297   ComplexPairTy VisitBinDivAssign(const CompoundAssignOperator *E) {
298     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinDiv);
299   }
300 
301   // GCC rejects rem/and/or/xor for integer complex.
302   // Logical and/or always return int, never complex.
303 
304   // No comparisons produce a complex result.
305 
306   LValue EmitBinAssignLValue(const BinaryOperator *E,
307                              ComplexPairTy &Val);
308   ComplexPairTy VisitBinAssign     (const BinaryOperator *E);
309   ComplexPairTy VisitBinComma      (const BinaryOperator *E);
310 
311 
312   ComplexPairTy
313   VisitAbstractConditionalOperator(const AbstractConditionalOperator *CO);
314   ComplexPairTy VisitChooseExpr(ChooseExpr *CE);
315 
316   ComplexPairTy VisitInitListExpr(InitListExpr *E);
317 
318   ComplexPairTy VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
319     return EmitLoadOfLValue(E);
320   }
321 
322   ComplexPairTy VisitVAArgExpr(VAArgExpr *E);
323 
324   ComplexPairTy VisitAtomicExpr(AtomicExpr *E) {
325     return CGF.EmitAtomicExpr(E).getComplexVal();
326   }
327 };
328 }  // end anonymous namespace.
329 
330 //===----------------------------------------------------------------------===//
331 //                                Utilities
332 //===----------------------------------------------------------------------===//
333 
334 Address CodeGenFunction::emitAddrOfRealComponent(Address addr,
335                                                  QualType complexType) {
336   return Builder.CreateStructGEP(addr, 0, addr.getName() + ".realp");
337 }
338 
339 Address CodeGenFunction::emitAddrOfImagComponent(Address addr,
340                                                  QualType complexType) {
341   return Builder.CreateStructGEP(addr, 1, addr.getName() + ".imagp");
342 }
343 
344 /// EmitLoadOfLValue - Given an RValue reference for a complex, emit code to
345 /// load the real and imaginary pieces, returning them as Real/Imag.
346 ComplexPairTy ComplexExprEmitter::EmitLoadOfLValue(LValue lvalue,
347                                                    SourceLocation loc) {
348   assert(lvalue.isSimple() && "non-simple complex l-value?");
349   if (lvalue.getType()->isAtomicType())
350     return CGF.EmitAtomicLoad(lvalue, loc).getComplexVal();
351 
352   Address SrcPtr = lvalue.getAddress(CGF);
353   bool isVolatile = lvalue.isVolatileQualified();
354 
355   llvm::Value *Real = nullptr, *Imag = nullptr;
356 
357   if (!IgnoreReal || isVolatile) {
358     Address RealP = CGF.emitAddrOfRealComponent(SrcPtr, lvalue.getType());
359     Real = Builder.CreateLoad(RealP, isVolatile, SrcPtr.getName() + ".real");
360   }
361 
362   if (!IgnoreImag || isVolatile) {
363     Address ImagP = CGF.emitAddrOfImagComponent(SrcPtr, lvalue.getType());
364     Imag = Builder.CreateLoad(ImagP, isVolatile, SrcPtr.getName() + ".imag");
365   }
366 
367   return ComplexPairTy(Real, Imag);
368 }
369 
370 /// EmitStoreOfComplex - Store the specified real/imag parts into the
371 /// specified value pointer.
372 void ComplexExprEmitter::EmitStoreOfComplex(ComplexPairTy Val, LValue lvalue,
373                                             bool isInit) {
374   if (lvalue.getType()->isAtomicType() ||
375       (!isInit && CGF.LValueIsSuitableForInlineAtomic(lvalue)))
376     return CGF.EmitAtomicStore(RValue::getComplex(Val), lvalue, isInit);
377 
378   Address Ptr = lvalue.getAddress(CGF);
379   Address RealPtr = CGF.emitAddrOfRealComponent(Ptr, lvalue.getType());
380   Address ImagPtr = CGF.emitAddrOfImagComponent(Ptr, lvalue.getType());
381 
382   Builder.CreateStore(Val.first, RealPtr, lvalue.isVolatileQualified());
383   Builder.CreateStore(Val.second, ImagPtr, lvalue.isVolatileQualified());
384 }
385 
386 
387 
388 //===----------------------------------------------------------------------===//
389 //                            Visitor Methods
390 //===----------------------------------------------------------------------===//
391 
392 ComplexPairTy ComplexExprEmitter::VisitExpr(Expr *E) {
393   CGF.ErrorUnsupported(E, "complex expression");
394   llvm::Type *EltTy =
395     CGF.ConvertType(getComplexType(E->getType())->getElementType());
396   llvm::Value *U = llvm::UndefValue::get(EltTy);
397   return ComplexPairTy(U, U);
398 }
399 
400 ComplexPairTy ComplexExprEmitter::
401 VisitImaginaryLiteral(const ImaginaryLiteral *IL) {
402   llvm::Value *Imag = CGF.EmitScalarExpr(IL->getSubExpr());
403   return ComplexPairTy(llvm::Constant::getNullValue(Imag->getType()), Imag);
404 }
405 
406 
407 ComplexPairTy ComplexExprEmitter::VisitCallExpr(const CallExpr *E) {
408   if (E->getCallReturnType(CGF.getContext())->isReferenceType())
409     return EmitLoadOfLValue(E);
410 
411   return CGF.EmitCallExpr(E).getComplexVal();
412 }
413 
414 ComplexPairTy ComplexExprEmitter::VisitStmtExpr(const StmtExpr *E) {
415   CodeGenFunction::StmtExprEvaluation eval(CGF);
416   Address RetAlloca = CGF.EmitCompoundStmt(*E->getSubStmt(), true);
417   assert(RetAlloca.isValid() && "Expected complex return value");
418   return EmitLoadOfLValue(CGF.MakeAddrLValue(RetAlloca, E->getType()),
419                           E->getExprLoc());
420 }
421 
422 /// Emit a cast from complex value Val to DestType.
423 ComplexPairTy ComplexExprEmitter::EmitComplexToComplexCast(ComplexPairTy Val,
424                                                            QualType SrcType,
425                                                            QualType DestType,
426                                                            SourceLocation Loc) {
427   // Get the src/dest element type.
428   SrcType = SrcType->castAs<ComplexType>()->getElementType();
429   DestType = DestType->castAs<ComplexType>()->getElementType();
430 
431   // C99 6.3.1.6: When a value of complex type is converted to another
432   // complex type, both the real and imaginary parts follow the conversion
433   // rules for the corresponding real types.
434   if (Val.first)
435     Val.first = CGF.EmitScalarConversion(Val.first, SrcType, DestType, Loc);
436   if (Val.second)
437     Val.second = CGF.EmitScalarConversion(Val.second, SrcType, DestType, Loc);
438   return Val;
439 }
440 
441 ComplexPairTy ComplexExprEmitter::EmitScalarToComplexCast(llvm::Value *Val,
442                                                           QualType SrcType,
443                                                           QualType DestType,
444                                                           SourceLocation Loc) {
445   // Convert the input element to the element type of the complex.
446   DestType = DestType->castAs<ComplexType>()->getElementType();
447   Val = CGF.EmitScalarConversion(Val, SrcType, DestType, Loc);
448 
449   // Return (realval, 0).
450   return ComplexPairTy(Val, llvm::Constant::getNullValue(Val->getType()));
451 }
452 
453 ComplexPairTy ComplexExprEmitter::EmitCast(CastKind CK, Expr *Op,
454                                            QualType DestTy) {
455   switch (CK) {
456   case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!");
457 
458   // Atomic to non-atomic casts may be more than a no-op for some platforms and
459   // for some types.
460   case CK_AtomicToNonAtomic:
461   case CK_NonAtomicToAtomic:
462   case CK_NoOp:
463   case CK_LValueToRValue:
464   case CK_UserDefinedConversion:
465     return Visit(Op);
466 
467   case CK_LValueBitCast: {
468     LValue origLV = CGF.EmitLValue(Op);
469     Address V = origLV.getAddress(CGF);
470     V = Builder.CreateElementBitCast(V, CGF.ConvertType(DestTy));
471     return EmitLoadOfLValue(CGF.MakeAddrLValue(V, DestTy), Op->getExprLoc());
472   }
473 
474   case CK_LValueToRValueBitCast: {
475     LValue SourceLVal = CGF.EmitLValue(Op);
476     Address Addr = Builder.CreateElementBitCast(SourceLVal.getAddress(CGF),
477                                                 CGF.ConvertTypeForMem(DestTy));
478     LValue DestLV = CGF.MakeAddrLValue(Addr, DestTy);
479     DestLV.setTBAAInfo(TBAAAccessInfo::getMayAliasInfo());
480     return EmitLoadOfLValue(DestLV, Op->getExprLoc());
481   }
482 
483   case CK_BitCast:
484   case CK_BaseToDerived:
485   case CK_DerivedToBase:
486   case CK_UncheckedDerivedToBase:
487   case CK_Dynamic:
488   case CK_ToUnion:
489   case CK_ArrayToPointerDecay:
490   case CK_FunctionToPointerDecay:
491   case CK_NullToPointer:
492   case CK_NullToMemberPointer:
493   case CK_BaseToDerivedMemberPointer:
494   case CK_DerivedToBaseMemberPointer:
495   case CK_MemberPointerToBoolean:
496   case CK_ReinterpretMemberPointer:
497   case CK_ConstructorConversion:
498   case CK_IntegralToPointer:
499   case CK_PointerToIntegral:
500   case CK_PointerToBoolean:
501   case CK_ToVoid:
502   case CK_VectorSplat:
503   case CK_IntegralCast:
504   case CK_BooleanToSignedIntegral:
505   case CK_IntegralToBoolean:
506   case CK_IntegralToFloating:
507   case CK_FloatingToIntegral:
508   case CK_FloatingToBoolean:
509   case CK_FloatingCast:
510   case CK_CPointerToObjCPointerCast:
511   case CK_BlockPointerToObjCPointerCast:
512   case CK_AnyPointerToBlockPointerCast:
513   case CK_ObjCObjectLValueCast:
514   case CK_FloatingComplexToReal:
515   case CK_FloatingComplexToBoolean:
516   case CK_IntegralComplexToReal:
517   case CK_IntegralComplexToBoolean:
518   case CK_ARCProduceObject:
519   case CK_ARCConsumeObject:
520   case CK_ARCReclaimReturnedObject:
521   case CK_ARCExtendBlockObject:
522   case CK_CopyAndAutoreleaseBlockObject:
523   case CK_BuiltinFnToFnPtr:
524   case CK_ZeroToOCLOpaqueType:
525   case CK_AddressSpaceConversion:
526   case CK_IntToOCLSampler:
527   case CK_FixedPointCast:
528   case CK_FixedPointToBoolean:
529   case CK_FixedPointToIntegral:
530   case CK_IntegralToFixedPoint:
531     llvm_unreachable("invalid cast kind for complex value");
532 
533   case CK_FloatingRealToComplex:
534   case CK_IntegralRealToComplex:
535     return EmitScalarToComplexCast(CGF.EmitScalarExpr(Op), Op->getType(),
536                                    DestTy, Op->getExprLoc());
537 
538   case CK_FloatingComplexCast:
539   case CK_FloatingComplexToIntegralComplex:
540   case CK_IntegralComplexCast:
541   case CK_IntegralComplexToFloatingComplex:
542     return EmitComplexToComplexCast(Visit(Op), Op->getType(), DestTy,
543                                     Op->getExprLoc());
544   }
545 
546   llvm_unreachable("unknown cast resulting in complex value");
547 }
548 
549 ComplexPairTy ComplexExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
550   TestAndClearIgnoreReal();
551   TestAndClearIgnoreImag();
552   ComplexPairTy Op = Visit(E->getSubExpr());
553 
554   llvm::Value *ResR, *ResI;
555   if (Op.first->getType()->isFloatingPointTy()) {
556     ResR = Builder.CreateFNeg(Op.first,  "neg.r");
557     ResI = Builder.CreateFNeg(Op.second, "neg.i");
558   } else {
559     ResR = Builder.CreateNeg(Op.first,  "neg.r");
560     ResI = Builder.CreateNeg(Op.second, "neg.i");
561   }
562   return ComplexPairTy(ResR, ResI);
563 }
564 
565 ComplexPairTy ComplexExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
566   TestAndClearIgnoreReal();
567   TestAndClearIgnoreImag();
568   // ~(a+ib) = a + i*-b
569   ComplexPairTy Op = Visit(E->getSubExpr());
570   llvm::Value *ResI;
571   if (Op.second->getType()->isFloatingPointTy())
572     ResI = Builder.CreateFNeg(Op.second, "conj.i");
573   else
574     ResI = Builder.CreateNeg(Op.second, "conj.i");
575 
576   return ComplexPairTy(Op.first, ResI);
577 }
578 
579 ComplexPairTy ComplexExprEmitter::EmitBinAdd(const BinOpInfo &Op) {
580   llvm::Value *ResR, *ResI;
581 
582   if (Op.LHS.first->getType()->isFloatingPointTy()) {
583     ResR = Builder.CreateFAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
584     if (Op.LHS.second && Op.RHS.second)
585       ResI = Builder.CreateFAdd(Op.LHS.second, Op.RHS.second, "add.i");
586     else
587       ResI = Op.LHS.second ? Op.LHS.second : Op.RHS.second;
588     assert(ResI && "Only one operand may be real!");
589   } else {
590     ResR = Builder.CreateAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
591     assert(Op.LHS.second && Op.RHS.second &&
592            "Both operands of integer complex operators must be complex!");
593     ResI = Builder.CreateAdd(Op.LHS.second, Op.RHS.second, "add.i");
594   }
595   return ComplexPairTy(ResR, ResI);
596 }
597 
598 ComplexPairTy ComplexExprEmitter::EmitBinSub(const BinOpInfo &Op) {
599   llvm::Value *ResR, *ResI;
600   if (Op.LHS.first->getType()->isFloatingPointTy()) {
601     ResR = Builder.CreateFSub(Op.LHS.first, Op.RHS.first, "sub.r");
602     if (Op.LHS.second && Op.RHS.second)
603       ResI = Builder.CreateFSub(Op.LHS.second, Op.RHS.second, "sub.i");
604     else
605       ResI = Op.LHS.second ? Op.LHS.second
606                            : Builder.CreateFNeg(Op.RHS.second, "sub.i");
607     assert(ResI && "Only one operand may be real!");
608   } else {
609     ResR = Builder.CreateSub(Op.LHS.first, Op.RHS.first, "sub.r");
610     assert(Op.LHS.second && Op.RHS.second &&
611            "Both operands of integer complex operators must be complex!");
612     ResI = Builder.CreateSub(Op.LHS.second, Op.RHS.second, "sub.i");
613   }
614   return ComplexPairTy(ResR, ResI);
615 }
616 
617 /// Emit a libcall for a binary operation on complex types.
618 ComplexPairTy ComplexExprEmitter::EmitComplexBinOpLibCall(StringRef LibCallName,
619                                                           const BinOpInfo &Op) {
620   CallArgList Args;
621   Args.add(RValue::get(Op.LHS.first),
622            Op.Ty->castAs<ComplexType>()->getElementType());
623   Args.add(RValue::get(Op.LHS.second),
624            Op.Ty->castAs<ComplexType>()->getElementType());
625   Args.add(RValue::get(Op.RHS.first),
626            Op.Ty->castAs<ComplexType>()->getElementType());
627   Args.add(RValue::get(Op.RHS.second),
628            Op.Ty->castAs<ComplexType>()->getElementType());
629 
630   // We *must* use the full CG function call building logic here because the
631   // complex type has special ABI handling. We also should not forget about
632   // special calling convention which may be used for compiler builtins.
633 
634   // We create a function qualified type to state that this call does not have
635   // any exceptions.
636   FunctionProtoType::ExtProtoInfo EPI;
637   EPI = EPI.withExceptionSpec(
638       FunctionProtoType::ExceptionSpecInfo(EST_BasicNoexcept));
639   SmallVector<QualType, 4> ArgsQTys(
640       4, Op.Ty->castAs<ComplexType>()->getElementType());
641   QualType FQTy = CGF.getContext().getFunctionType(Op.Ty, ArgsQTys, EPI);
642   const CGFunctionInfo &FuncInfo = CGF.CGM.getTypes().arrangeFreeFunctionCall(
643       Args, cast<FunctionType>(FQTy.getTypePtr()), false);
644 
645   llvm::FunctionType *FTy = CGF.CGM.getTypes().GetFunctionType(FuncInfo);
646   llvm::FunctionCallee Func = CGF.CGM.CreateRuntimeFunction(
647       FTy, LibCallName, llvm::AttributeList(), true);
648   CGCallee Callee = CGCallee::forDirect(Func, FQTy->getAs<FunctionProtoType>());
649 
650   llvm::CallBase *Call;
651   RValue Res = CGF.EmitCall(FuncInfo, Callee, ReturnValueSlot(), Args, &Call);
652   Call->setCallingConv(CGF.CGM.getRuntimeCC());
653   return Res.getComplexVal();
654 }
655 
656 /// Lookup the libcall name for a given floating point type complex
657 /// multiply.
658 static StringRef getComplexMultiplyLibCallName(llvm::Type *Ty) {
659   switch (Ty->getTypeID()) {
660   default:
661     llvm_unreachable("Unsupported floating point type!");
662   case llvm::Type::HalfTyID:
663     return "__mulhc3";
664   case llvm::Type::FloatTyID:
665     return "__mulsc3";
666   case llvm::Type::DoubleTyID:
667     return "__muldc3";
668   case llvm::Type::PPC_FP128TyID:
669     return "__multc3";
670   case llvm::Type::X86_FP80TyID:
671     return "__mulxc3";
672   case llvm::Type::FP128TyID:
673     return "__multc3";
674   }
675 }
676 
677 // See C11 Annex G.5.1 for the semantics of multiplicative operators on complex
678 // typed values.
679 ComplexPairTy ComplexExprEmitter::EmitBinMul(const BinOpInfo &Op) {
680   using llvm::Value;
681   Value *ResR, *ResI;
682   llvm::MDBuilder MDHelper(CGF.getLLVMContext());
683 
684   if (Op.LHS.first->getType()->isFloatingPointTy()) {
685     // The general formulation is:
686     // (a + ib) * (c + id) = (a * c - b * d) + i(a * d + b * c)
687     //
688     // But we can fold away components which would be zero due to a real
689     // operand according to C11 Annex G.5.1p2.
690     // FIXME: C11 also provides for imaginary types which would allow folding
691     // still more of this within the type system.
692 
693     if (Op.LHS.second && Op.RHS.second) {
694       // If both operands are complex, emit the core math directly, and then
695       // test for NaNs. If we find NaNs in the result, we delegate to a libcall
696       // to carefully re-compute the correct infinity representation if
697       // possible. The expectation is that the presence of NaNs here is
698       // *extremely* rare, and so the cost of the libcall is almost irrelevant.
699       // This is good, because the libcall re-computes the core multiplication
700       // exactly the same as we do here and re-tests for NaNs in order to be
701       // a generic complex*complex libcall.
702 
703       // First compute the four products.
704       Value *AC = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul_ac");
705       Value *BD = Builder.CreateFMul(Op.LHS.second, Op.RHS.second, "mul_bd");
706       Value *AD = Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul_ad");
707       Value *BC = Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul_bc");
708 
709       // The real part is the difference of the first two, the imaginary part is
710       // the sum of the second.
711       ResR = Builder.CreateFSub(AC, BD, "mul_r");
712       ResI = Builder.CreateFAdd(AD, BC, "mul_i");
713 
714       // Emit the test for the real part becoming NaN and create a branch to
715       // handle it. We test for NaN by comparing the number to itself.
716       Value *IsRNaN = Builder.CreateFCmpUNO(ResR, ResR, "isnan_cmp");
717       llvm::BasicBlock *ContBB = CGF.createBasicBlock("complex_mul_cont");
718       llvm::BasicBlock *INaNBB = CGF.createBasicBlock("complex_mul_imag_nan");
719       llvm::Instruction *Branch = Builder.CreateCondBr(IsRNaN, INaNBB, ContBB);
720       llvm::BasicBlock *OrigBB = Branch->getParent();
721 
722       // Give hint that we very much don't expect to see NaNs.
723       // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
724       llvm::MDNode *BrWeight = MDHelper.createBranchWeights(1, (1U << 20) - 1);
725       Branch->setMetadata(llvm::LLVMContext::MD_prof, BrWeight);
726 
727       // Now test the imaginary part and create its branch.
728       CGF.EmitBlock(INaNBB);
729       Value *IsINaN = Builder.CreateFCmpUNO(ResI, ResI, "isnan_cmp");
730       llvm::BasicBlock *LibCallBB = CGF.createBasicBlock("complex_mul_libcall");
731       Branch = Builder.CreateCondBr(IsINaN, LibCallBB, ContBB);
732       Branch->setMetadata(llvm::LLVMContext::MD_prof, BrWeight);
733 
734       // Now emit the libcall on this slowest of the slow paths.
735       CGF.EmitBlock(LibCallBB);
736       Value *LibCallR, *LibCallI;
737       std::tie(LibCallR, LibCallI) = EmitComplexBinOpLibCall(
738           getComplexMultiplyLibCallName(Op.LHS.first->getType()), Op);
739       Builder.CreateBr(ContBB);
740 
741       // Finally continue execution by phi-ing together the different
742       // computation paths.
743       CGF.EmitBlock(ContBB);
744       llvm::PHINode *RealPHI = Builder.CreatePHI(ResR->getType(), 3, "real_mul_phi");
745       RealPHI->addIncoming(ResR, OrigBB);
746       RealPHI->addIncoming(ResR, INaNBB);
747       RealPHI->addIncoming(LibCallR, LibCallBB);
748       llvm::PHINode *ImagPHI = Builder.CreatePHI(ResI->getType(), 3, "imag_mul_phi");
749       ImagPHI->addIncoming(ResI, OrigBB);
750       ImagPHI->addIncoming(ResI, INaNBB);
751       ImagPHI->addIncoming(LibCallI, LibCallBB);
752       return ComplexPairTy(RealPHI, ImagPHI);
753     }
754     assert((Op.LHS.second || Op.RHS.second) &&
755            "At least one operand must be complex!");
756 
757     // If either of the operands is a real rather than a complex, the
758     // imaginary component is ignored when computing the real component of the
759     // result.
760     ResR = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul.rl");
761 
762     ResI = Op.LHS.second
763                ? Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul.il")
764                : Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul.ir");
765   } else {
766     assert(Op.LHS.second && Op.RHS.second &&
767            "Both operands of integer complex operators must be complex!");
768     Value *ResRl = Builder.CreateMul(Op.LHS.first, Op.RHS.first, "mul.rl");
769     Value *ResRr = Builder.CreateMul(Op.LHS.second, Op.RHS.second, "mul.rr");
770     ResR = Builder.CreateSub(ResRl, ResRr, "mul.r");
771 
772     Value *ResIl = Builder.CreateMul(Op.LHS.second, Op.RHS.first, "mul.il");
773     Value *ResIr = Builder.CreateMul(Op.LHS.first, Op.RHS.second, "mul.ir");
774     ResI = Builder.CreateAdd(ResIl, ResIr, "mul.i");
775   }
776   return ComplexPairTy(ResR, ResI);
777 }
778 
779 // See C11 Annex G.5.1 for the semantics of multiplicative operators on complex
780 // typed values.
781 ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
782   llvm::Value *LHSr = Op.LHS.first, *LHSi = Op.LHS.second;
783   llvm::Value *RHSr = Op.RHS.first, *RHSi = Op.RHS.second;
784 
785   llvm::Value *DSTr, *DSTi;
786   if (LHSr->getType()->isFloatingPointTy()) {
787     // If we have a complex operand on the RHS and FastMath is not allowed, we
788     // delegate to a libcall to handle all of the complexities and minimize
789     // underflow/overflow cases. When FastMath is allowed we construct the
790     // divide inline using the same algorithm as for integer operands.
791     //
792     // FIXME: We would be able to avoid the libcall in many places if we
793     // supported imaginary types in addition to complex types.
794     if (RHSi && !CGF.getLangOpts().FastMath) {
795       BinOpInfo LibCallOp = Op;
796       // If LHS was a real, supply a null imaginary part.
797       if (!LHSi)
798         LibCallOp.LHS.second = llvm::Constant::getNullValue(LHSr->getType());
799 
800       switch (LHSr->getType()->getTypeID()) {
801       default:
802         llvm_unreachable("Unsupported floating point type!");
803       case llvm::Type::HalfTyID:
804         return EmitComplexBinOpLibCall("__divhc3", LibCallOp);
805       case llvm::Type::FloatTyID:
806         return EmitComplexBinOpLibCall("__divsc3", LibCallOp);
807       case llvm::Type::DoubleTyID:
808         return EmitComplexBinOpLibCall("__divdc3", LibCallOp);
809       case llvm::Type::PPC_FP128TyID:
810         return EmitComplexBinOpLibCall("__divtc3", LibCallOp);
811       case llvm::Type::X86_FP80TyID:
812         return EmitComplexBinOpLibCall("__divxc3", LibCallOp);
813       case llvm::Type::FP128TyID:
814         return EmitComplexBinOpLibCall("__divtc3", LibCallOp);
815       }
816     } else if (RHSi) {
817       if (!LHSi)
818         LHSi = llvm::Constant::getNullValue(RHSi->getType());
819 
820       // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
821       llvm::Value *AC = Builder.CreateFMul(LHSr, RHSr); // a*c
822       llvm::Value *BD = Builder.CreateFMul(LHSi, RHSi); // b*d
823       llvm::Value *ACpBD = Builder.CreateFAdd(AC, BD); // ac+bd
824 
825       llvm::Value *CC = Builder.CreateFMul(RHSr, RHSr); // c*c
826       llvm::Value *DD = Builder.CreateFMul(RHSi, RHSi); // d*d
827       llvm::Value *CCpDD = Builder.CreateFAdd(CC, DD); // cc+dd
828 
829       llvm::Value *BC = Builder.CreateFMul(LHSi, RHSr); // b*c
830       llvm::Value *AD = Builder.CreateFMul(LHSr, RHSi); // a*d
831       llvm::Value *BCmAD = Builder.CreateFSub(BC, AD); // bc-ad
832 
833       DSTr = Builder.CreateFDiv(ACpBD, CCpDD);
834       DSTi = Builder.CreateFDiv(BCmAD, CCpDD);
835     } else {
836       assert(LHSi && "Can have at most one non-complex operand!");
837 
838       DSTr = Builder.CreateFDiv(LHSr, RHSr);
839       DSTi = Builder.CreateFDiv(LHSi, RHSr);
840     }
841   } else {
842     assert(Op.LHS.second && Op.RHS.second &&
843            "Both operands of integer complex operators must be complex!");
844     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
845     llvm::Value *Tmp1 = Builder.CreateMul(LHSr, RHSr); // a*c
846     llvm::Value *Tmp2 = Builder.CreateMul(LHSi, RHSi); // b*d
847     llvm::Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2); // ac+bd
848 
849     llvm::Value *Tmp4 = Builder.CreateMul(RHSr, RHSr); // c*c
850     llvm::Value *Tmp5 = Builder.CreateMul(RHSi, RHSi); // d*d
851     llvm::Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5); // cc+dd
852 
853     llvm::Value *Tmp7 = Builder.CreateMul(LHSi, RHSr); // b*c
854     llvm::Value *Tmp8 = Builder.CreateMul(LHSr, RHSi); // a*d
855     llvm::Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8); // bc-ad
856 
857     if (Op.Ty->castAs<ComplexType>()->getElementType()->isUnsignedIntegerType()) {
858       DSTr = Builder.CreateUDiv(Tmp3, Tmp6);
859       DSTi = Builder.CreateUDiv(Tmp9, Tmp6);
860     } else {
861       DSTr = Builder.CreateSDiv(Tmp3, Tmp6);
862       DSTi = Builder.CreateSDiv(Tmp9, Tmp6);
863     }
864   }
865 
866   return ComplexPairTy(DSTr, DSTi);
867 }
868 
869 ComplexExprEmitter::BinOpInfo
870 ComplexExprEmitter::EmitBinOps(const BinaryOperator *E) {
871   TestAndClearIgnoreReal();
872   TestAndClearIgnoreImag();
873   BinOpInfo Ops;
874   if (E->getLHS()->getType()->isRealFloatingType())
875     Ops.LHS = ComplexPairTy(CGF.EmitScalarExpr(E->getLHS()), nullptr);
876   else
877     Ops.LHS = Visit(E->getLHS());
878   if (E->getRHS()->getType()->isRealFloatingType())
879     Ops.RHS = ComplexPairTy(CGF.EmitScalarExpr(E->getRHS()), nullptr);
880   else
881     Ops.RHS = Visit(E->getRHS());
882 
883   Ops.Ty = E->getType();
884   return Ops;
885 }
886 
887 
888 LValue ComplexExprEmitter::
889 EmitCompoundAssignLValue(const CompoundAssignOperator *E,
890           ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&),
891                          RValue &Val) {
892   TestAndClearIgnoreReal();
893   TestAndClearIgnoreImag();
894   QualType LHSTy = E->getLHS()->getType();
895   if (const AtomicType *AT = LHSTy->getAs<AtomicType>())
896     LHSTy = AT->getValueType();
897 
898   BinOpInfo OpInfo;
899 
900   // Load the RHS and LHS operands.
901   // __block variables need to have the rhs evaluated first, plus this should
902   // improve codegen a little.
903   OpInfo.Ty = E->getComputationResultType();
904   QualType ComplexElementTy = cast<ComplexType>(OpInfo.Ty)->getElementType();
905 
906   // The RHS should have been converted to the computation type.
907   if (E->getRHS()->getType()->isRealFloatingType()) {
908     assert(
909         CGF.getContext()
910             .hasSameUnqualifiedType(ComplexElementTy, E->getRHS()->getType()));
911     OpInfo.RHS = ComplexPairTy(CGF.EmitScalarExpr(E->getRHS()), nullptr);
912   } else {
913     assert(CGF.getContext()
914                .hasSameUnqualifiedType(OpInfo.Ty, E->getRHS()->getType()));
915     OpInfo.RHS = Visit(E->getRHS());
916   }
917 
918   LValue LHS = CGF.EmitLValue(E->getLHS());
919 
920   // Load from the l-value and convert it.
921   SourceLocation Loc = E->getExprLoc();
922   if (LHSTy->isAnyComplexType()) {
923     ComplexPairTy LHSVal = EmitLoadOfLValue(LHS, Loc);
924     OpInfo.LHS = EmitComplexToComplexCast(LHSVal, LHSTy, OpInfo.Ty, Loc);
925   } else {
926     llvm::Value *LHSVal = CGF.EmitLoadOfScalar(LHS, Loc);
927     // For floating point real operands we can directly pass the scalar form
928     // to the binary operator emission and potentially get more efficient code.
929     if (LHSTy->isRealFloatingType()) {
930       if (!CGF.getContext().hasSameUnqualifiedType(ComplexElementTy, LHSTy))
931         LHSVal = CGF.EmitScalarConversion(LHSVal, LHSTy, ComplexElementTy, Loc);
932       OpInfo.LHS = ComplexPairTy(LHSVal, nullptr);
933     } else {
934       OpInfo.LHS = EmitScalarToComplexCast(LHSVal, LHSTy, OpInfo.Ty, Loc);
935     }
936   }
937 
938   // Expand the binary operator.
939   ComplexPairTy Result = (this->*Func)(OpInfo);
940 
941   // Truncate the result and store it into the LHS lvalue.
942   if (LHSTy->isAnyComplexType()) {
943     ComplexPairTy ResVal =
944         EmitComplexToComplexCast(Result, OpInfo.Ty, LHSTy, Loc);
945     EmitStoreOfComplex(ResVal, LHS, /*isInit*/ false);
946     Val = RValue::getComplex(ResVal);
947   } else {
948     llvm::Value *ResVal =
949         CGF.EmitComplexToScalarConversion(Result, OpInfo.Ty, LHSTy, Loc);
950     CGF.EmitStoreOfScalar(ResVal, LHS, /*isInit*/ false);
951     Val = RValue::get(ResVal);
952   }
953 
954   return LHS;
955 }
956 
957 // Compound assignments.
958 ComplexPairTy ComplexExprEmitter::
959 EmitCompoundAssign(const CompoundAssignOperator *E,
960                    ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&)){
961   RValue Val;
962   LValue LV = EmitCompoundAssignLValue(E, Func, Val);
963 
964   // The result of an assignment in C is the assigned r-value.
965   if (!CGF.getLangOpts().CPlusPlus)
966     return Val.getComplexVal();
967 
968   // If the lvalue is non-volatile, return the computed value of the assignment.
969   if (!LV.isVolatileQualified())
970     return Val.getComplexVal();
971 
972   return EmitLoadOfLValue(LV, E->getExprLoc());
973 }
974 
975 LValue ComplexExprEmitter::EmitBinAssignLValue(const BinaryOperator *E,
976                                                ComplexPairTy &Val) {
977   assert(CGF.getContext().hasSameUnqualifiedType(E->getLHS()->getType(),
978                                                  E->getRHS()->getType()) &&
979          "Invalid assignment");
980   TestAndClearIgnoreReal();
981   TestAndClearIgnoreImag();
982 
983   // Emit the RHS.  __block variables need the RHS evaluated first.
984   Val = Visit(E->getRHS());
985 
986   // Compute the address to store into.
987   LValue LHS = CGF.EmitLValue(E->getLHS());
988 
989   // Store the result value into the LHS lvalue.
990   EmitStoreOfComplex(Val, LHS, /*isInit*/ false);
991 
992   return LHS;
993 }
994 
995 ComplexPairTy ComplexExprEmitter::VisitBinAssign(const BinaryOperator *E) {
996   ComplexPairTy Val;
997   LValue LV = EmitBinAssignLValue(E, Val);
998 
999   // The result of an assignment in C is the assigned r-value.
1000   if (!CGF.getLangOpts().CPlusPlus)
1001     return Val;
1002 
1003   // If the lvalue is non-volatile, return the computed value of the assignment.
1004   if (!LV.isVolatileQualified())
1005     return Val;
1006 
1007   return EmitLoadOfLValue(LV, E->getExprLoc());
1008 }
1009 
1010 ComplexPairTy ComplexExprEmitter::VisitBinComma(const BinaryOperator *E) {
1011   CGF.EmitIgnoredExpr(E->getLHS());
1012   return Visit(E->getRHS());
1013 }
1014 
1015 ComplexPairTy ComplexExprEmitter::
1016 VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) {
1017   TestAndClearIgnoreReal();
1018   TestAndClearIgnoreImag();
1019   llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
1020   llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
1021   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
1022 
1023   // Bind the common expression if necessary.
1024   CodeGenFunction::OpaqueValueMapping binding(CGF, E);
1025 
1026 
1027   CodeGenFunction::ConditionalEvaluation eval(CGF);
1028   CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock,
1029                            CGF.getProfileCount(E));
1030 
1031   eval.begin(CGF);
1032   CGF.EmitBlock(LHSBlock);
1033   CGF.incrementProfileCounter(E);
1034   ComplexPairTy LHS = Visit(E->getTrueExpr());
1035   LHSBlock = Builder.GetInsertBlock();
1036   CGF.EmitBranch(ContBlock);
1037   eval.end(CGF);
1038 
1039   eval.begin(CGF);
1040   CGF.EmitBlock(RHSBlock);
1041   ComplexPairTy RHS = Visit(E->getFalseExpr());
1042   RHSBlock = Builder.GetInsertBlock();
1043   CGF.EmitBlock(ContBlock);
1044   eval.end(CGF);
1045 
1046   // Create a PHI node for the real part.
1047   llvm::PHINode *RealPN = Builder.CreatePHI(LHS.first->getType(), 2, "cond.r");
1048   RealPN->addIncoming(LHS.first, LHSBlock);
1049   RealPN->addIncoming(RHS.first, RHSBlock);
1050 
1051   // Create a PHI node for the imaginary part.
1052   llvm::PHINode *ImagPN = Builder.CreatePHI(LHS.first->getType(), 2, "cond.i");
1053   ImagPN->addIncoming(LHS.second, LHSBlock);
1054   ImagPN->addIncoming(RHS.second, RHSBlock);
1055 
1056   return ComplexPairTy(RealPN, ImagPN);
1057 }
1058 
1059 ComplexPairTy ComplexExprEmitter::VisitChooseExpr(ChooseExpr *E) {
1060   return Visit(E->getChosenSubExpr());
1061 }
1062 
1063 ComplexPairTy ComplexExprEmitter::VisitInitListExpr(InitListExpr *E) {
1064     bool Ignore = TestAndClearIgnoreReal();
1065     (void)Ignore;
1066     assert (Ignore == false && "init list ignored");
1067     Ignore = TestAndClearIgnoreImag();
1068     (void)Ignore;
1069     assert (Ignore == false && "init list ignored");
1070 
1071   if (E->getNumInits() == 2) {
1072     llvm::Value *Real = CGF.EmitScalarExpr(E->getInit(0));
1073     llvm::Value *Imag = CGF.EmitScalarExpr(E->getInit(1));
1074     return ComplexPairTy(Real, Imag);
1075   } else if (E->getNumInits() == 1) {
1076     return Visit(E->getInit(0));
1077   }
1078 
1079   // Empty init list initializes to null
1080   assert(E->getNumInits() == 0 && "Unexpected number of inits");
1081   QualType Ty = E->getType()->castAs<ComplexType>()->getElementType();
1082   llvm::Type* LTy = CGF.ConvertType(Ty);
1083   llvm::Value* zeroConstant = llvm::Constant::getNullValue(LTy);
1084   return ComplexPairTy(zeroConstant, zeroConstant);
1085 }
1086 
1087 ComplexPairTy ComplexExprEmitter::VisitVAArgExpr(VAArgExpr *E) {
1088   Address ArgValue = Address::invalid();
1089   Address ArgPtr = CGF.EmitVAArg(E, ArgValue);
1090 
1091   if (!ArgPtr.isValid()) {
1092     CGF.ErrorUnsupported(E, "complex va_arg expression");
1093     llvm::Type *EltTy =
1094       CGF.ConvertType(E->getType()->castAs<ComplexType>()->getElementType());
1095     llvm::Value *U = llvm::UndefValue::get(EltTy);
1096     return ComplexPairTy(U, U);
1097   }
1098 
1099   return EmitLoadOfLValue(CGF.MakeAddrLValue(ArgPtr, E->getType()),
1100                           E->getExprLoc());
1101 }
1102 
1103 //===----------------------------------------------------------------------===//
1104 //                         Entry Point into this File
1105 //===----------------------------------------------------------------------===//
1106 
1107 /// EmitComplexExpr - Emit the computation of the specified expression of
1108 /// complex type, ignoring the result.
1109 ComplexPairTy CodeGenFunction::EmitComplexExpr(const Expr *E, bool IgnoreReal,
1110                                                bool IgnoreImag) {
1111   assert(E && getComplexType(E->getType()) &&
1112          "Invalid complex expression to emit");
1113 
1114   return ComplexExprEmitter(*this, IgnoreReal, IgnoreImag)
1115       .Visit(const_cast<Expr *>(E));
1116 }
1117 
1118 void CodeGenFunction::EmitComplexExprIntoLValue(const Expr *E, LValue dest,
1119                                                 bool isInit) {
1120   assert(E && getComplexType(E->getType()) &&
1121          "Invalid complex expression to emit");
1122   ComplexExprEmitter Emitter(*this);
1123   ComplexPairTy Val = Emitter.Visit(const_cast<Expr*>(E));
1124   Emitter.EmitStoreOfComplex(Val, dest, isInit);
1125 }
1126 
1127 /// EmitStoreOfComplex - Store a complex number into the specified l-value.
1128 void CodeGenFunction::EmitStoreOfComplex(ComplexPairTy V, LValue dest,
1129                                          bool isInit) {
1130   ComplexExprEmitter(*this).EmitStoreOfComplex(V, dest, isInit);
1131 }
1132 
1133 /// EmitLoadOfComplex - Load a complex number from the specified address.
1134 ComplexPairTy CodeGenFunction::EmitLoadOfComplex(LValue src,
1135                                                  SourceLocation loc) {
1136   return ComplexExprEmitter(*this).EmitLoadOfLValue(src, loc);
1137 }
1138 
1139 LValue CodeGenFunction::EmitComplexAssignmentLValue(const BinaryOperator *E) {
1140   assert(E->getOpcode() == BO_Assign);
1141   ComplexPairTy Val; // ignored
1142   LValue LVal = ComplexExprEmitter(*this).EmitBinAssignLValue(E, Val);
1143   if (getLangOpts().OpenMP)
1144     CGM.getOpenMPRuntime().checkAndEmitLastprivateConditional(*this,
1145                                                               E->getLHS());
1146   return LVal;
1147 }
1148 
1149 typedef ComplexPairTy (ComplexExprEmitter::*CompoundFunc)(
1150     const ComplexExprEmitter::BinOpInfo &);
1151 
1152 static CompoundFunc getComplexOp(BinaryOperatorKind Op) {
1153   switch (Op) {
1154   case BO_MulAssign: return &ComplexExprEmitter::EmitBinMul;
1155   case BO_DivAssign: return &ComplexExprEmitter::EmitBinDiv;
1156   case BO_SubAssign: return &ComplexExprEmitter::EmitBinSub;
1157   case BO_AddAssign: return &ComplexExprEmitter::EmitBinAdd;
1158   default:
1159     llvm_unreachable("unexpected complex compound assignment");
1160   }
1161 }
1162 
1163 LValue CodeGenFunction::
1164 EmitComplexCompoundAssignmentLValue(const CompoundAssignOperator *E) {
1165   CompoundFunc Op = getComplexOp(E->getOpcode());
1166   RValue Val;
1167   return ComplexExprEmitter(*this).EmitCompoundAssignLValue(E, Op, Val);
1168 }
1169 
1170 LValue CodeGenFunction::
1171 EmitScalarCompoundAssignWithComplex(const CompoundAssignOperator *E,
1172                                     llvm::Value *&Result) {
1173   CompoundFunc Op = getComplexOp(E->getOpcode());
1174   RValue Val;
1175   LValue Ret = ComplexExprEmitter(*this).EmitCompoundAssignLValue(E, Op, Val);
1176   Result = Val.getScalarVal();
1177   return Ret;
1178 }
1179