1 //===--- CGExprComplex.cpp - Emit LLVM Code for Complex Exprs -------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This contains code to emit Expr nodes with complex types as LLVM code.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "CodeGenFunction.h"
15 #include "CodeGenModule.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/StmtVisitor.h"
18 #include "llvm/Constants.h"
19 #include "llvm/Function.h"
20 #include "llvm/ADT/SmallString.h"
21 using namespace clang;
22 using namespace CodeGen;
23 
24 //===----------------------------------------------------------------------===//
25 //                        Complex Expression Emitter
26 //===----------------------------------------------------------------------===//
27 
28 typedef CodeGenFunction::ComplexPairTy ComplexPairTy;
29 
30 namespace  {
31 class ComplexExprEmitter
32   : public StmtVisitor<ComplexExprEmitter, ComplexPairTy> {
33   CodeGenFunction &CGF;
34   CGBuilderTy &Builder;
35   // True is we should ignore the value of a
36   bool IgnoreReal;
37   bool IgnoreImag;
38 public:
39   ComplexExprEmitter(CodeGenFunction &cgf, bool ir=false, bool ii=false)
40     : CGF(cgf), Builder(CGF.Builder), IgnoreReal(ir), IgnoreImag(ii) {
41   }
42 
43 
44   //===--------------------------------------------------------------------===//
45   //                               Utilities
46   //===--------------------------------------------------------------------===//
47 
48   bool TestAndClearIgnoreReal() {
49     bool I = IgnoreReal;
50     IgnoreReal = false;
51     return I;
52   }
53   bool TestAndClearIgnoreImag() {
54     bool I = IgnoreImag;
55     IgnoreImag = false;
56     return I;
57   }
58 
59   /// EmitLoadOfLValue - Given an expression with complex type that represents a
60   /// value l-value, this method emits the address of the l-value, then loads
61   /// and returns the result.
62   ComplexPairTy EmitLoadOfLValue(const Expr *E) {
63     return EmitLoadOfLValue(CGF.EmitLValue(E));
64   }
65 
66   ComplexPairTy EmitLoadOfLValue(LValue LV) {
67     assert(LV.isSimple() && "complex l-value must be simple");
68     return EmitLoadOfComplex(LV.getAddress(), LV.isVolatileQualified());
69   }
70 
71   /// EmitLoadOfComplex - Given a pointer to a complex value, emit code to load
72   /// the real and imaginary pieces.
73   ComplexPairTy EmitLoadOfComplex(llvm::Value *SrcPtr, bool isVolatile);
74 
75   /// EmitStoreThroughLValue - Given an l-value of complex type, store
76   /// a complex number into it.
77   void EmitStoreThroughLValue(ComplexPairTy Val, LValue LV) {
78     assert(LV.isSimple() && "complex l-value must be simple");
79     return EmitStoreOfComplex(Val, LV.getAddress(), LV.isVolatileQualified());
80   }
81 
82   /// EmitStoreOfComplex - Store the specified real/imag parts into the
83   /// specified value pointer.
84   void EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *ResPtr, bool isVol);
85 
86   /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
87   ComplexPairTy EmitComplexToComplexCast(ComplexPairTy Val, QualType SrcType,
88                                          QualType DestType);
89 
90   //===--------------------------------------------------------------------===//
91   //                            Visitor Methods
92   //===--------------------------------------------------------------------===//
93 
94   ComplexPairTy Visit(Expr *E) {
95     return StmtVisitor<ComplexExprEmitter, ComplexPairTy>::Visit(E);
96   }
97 
98   ComplexPairTy VisitStmt(Stmt *S) {
99     S->dump(CGF.getContext().getSourceManager());
100     llvm_unreachable("Stmt can't have complex result type!");
101   }
102   ComplexPairTy VisitExpr(Expr *S);
103   ComplexPairTy VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr());}
104   ComplexPairTy VisitGenericSelectionExpr(GenericSelectionExpr *GE) {
105     return Visit(GE->getResultExpr());
106   }
107   ComplexPairTy VisitImaginaryLiteral(const ImaginaryLiteral *IL);
108   ComplexPairTy
109   VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE) {
110     return Visit(PE->getReplacement());
111   }
112 
113   // l-values.
114   ComplexPairTy emitDeclRef(ValueDecl *VD, Expr *refExpr) {
115     if (CodeGenFunction::ConstantEmission result
116           = CGF.tryEmitAsConstant(VD, refExpr)) {
117       if (result.isReference())
118         return EmitLoadOfLValue(result.getReferenceLValue(CGF, refExpr));
119 
120       llvm::ConstantStruct *pair =
121         cast<llvm::ConstantStruct>(result.getValue());
122       return ComplexPairTy(pair->getOperand(0), pair->getOperand(1));
123     }
124     return EmitLoadOfLValue(refExpr);
125   }
126   ComplexPairTy VisitDeclRefExpr(DeclRefExpr *E) {
127     return emitDeclRef(E->getDecl(), E);
128   }
129   ComplexPairTy VisitBlockDeclRefExpr(BlockDeclRefExpr *E) {
130     return emitDeclRef(E->getDecl(), E);
131   }
132   ComplexPairTy VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
133     return EmitLoadOfLValue(E);
134   }
135   ComplexPairTy VisitObjCMessageExpr(ObjCMessageExpr *E) {
136     return CGF.EmitObjCMessageExpr(E).getComplexVal();
137   }
138   ComplexPairTy VisitArraySubscriptExpr(Expr *E) { return EmitLoadOfLValue(E); }
139   ComplexPairTy VisitMemberExpr(const Expr *E) { return EmitLoadOfLValue(E); }
140   ComplexPairTy VisitOpaqueValueExpr(OpaqueValueExpr *E) {
141     if (E->isGLValue())
142       return EmitLoadOfLValue(CGF.getOpaqueLValueMapping(E));
143     return CGF.getOpaqueRValueMapping(E).getComplexVal();
144   }
145 
146   ComplexPairTy VisitPseudoObjectExpr(PseudoObjectExpr *E) {
147     return CGF.EmitPseudoObjectRValue(E).getComplexVal();
148   }
149 
150   // FIXME: CompoundLiteralExpr
151 
152   ComplexPairTy EmitCast(CastExpr::CastKind CK, Expr *Op, QualType DestTy);
153   ComplexPairTy VisitImplicitCastExpr(ImplicitCastExpr *E) {
154     // Unlike for scalars, we don't have to worry about function->ptr demotion
155     // here.
156     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
157   }
158   ComplexPairTy VisitCastExpr(CastExpr *E) {
159     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
160   }
161   ComplexPairTy VisitCallExpr(const CallExpr *E);
162   ComplexPairTy VisitStmtExpr(const StmtExpr *E);
163 
164   // Operators.
165   ComplexPairTy VisitPrePostIncDec(const UnaryOperator *E,
166                                    bool isInc, bool isPre) {
167     LValue LV = CGF.EmitLValue(E->getSubExpr());
168     return CGF.EmitComplexPrePostIncDec(E, LV, isInc, isPre);
169   }
170   ComplexPairTy VisitUnaryPostDec(const UnaryOperator *E) {
171     return VisitPrePostIncDec(E, false, false);
172   }
173   ComplexPairTy VisitUnaryPostInc(const UnaryOperator *E) {
174     return VisitPrePostIncDec(E, true, false);
175   }
176   ComplexPairTy VisitUnaryPreDec(const UnaryOperator *E) {
177     return VisitPrePostIncDec(E, false, true);
178   }
179   ComplexPairTy VisitUnaryPreInc(const UnaryOperator *E) {
180     return VisitPrePostIncDec(E, true, true);
181   }
182   ComplexPairTy VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); }
183   ComplexPairTy VisitUnaryPlus     (const UnaryOperator *E) {
184     TestAndClearIgnoreReal();
185     TestAndClearIgnoreImag();
186     return Visit(E->getSubExpr());
187   }
188   ComplexPairTy VisitUnaryMinus    (const UnaryOperator *E);
189   ComplexPairTy VisitUnaryNot      (const UnaryOperator *E);
190   // LNot,Real,Imag never return complex.
191   ComplexPairTy VisitUnaryExtension(const UnaryOperator *E) {
192     return Visit(E->getSubExpr());
193   }
194   ComplexPairTy VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
195     return Visit(DAE->getExpr());
196   }
197   ComplexPairTy VisitExprWithCleanups(ExprWithCleanups *E) {
198     CGF.enterFullExpression(E);
199     CodeGenFunction::RunCleanupsScope Scope(CGF);
200     return Visit(E->getSubExpr());
201   }
202   ComplexPairTy VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E) {
203     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
204     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
205     llvm::Constant *Null = llvm::Constant::getNullValue(CGF.ConvertType(Elem));
206     return ComplexPairTy(Null, Null);
207   }
208   ComplexPairTy VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
209     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
210     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
211     llvm::Constant *Null =
212                        llvm::Constant::getNullValue(CGF.ConvertType(Elem));
213     return ComplexPairTy(Null, Null);
214   }
215 
216   struct BinOpInfo {
217     ComplexPairTy LHS;
218     ComplexPairTy RHS;
219     QualType Ty;  // Computation Type.
220   };
221 
222   BinOpInfo EmitBinOps(const BinaryOperator *E);
223   LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E,
224                                   ComplexPairTy (ComplexExprEmitter::*Func)
225                                   (const BinOpInfo &),
226                                   ComplexPairTy &Val);
227   ComplexPairTy EmitCompoundAssign(const CompoundAssignOperator *E,
228                                    ComplexPairTy (ComplexExprEmitter::*Func)
229                                    (const BinOpInfo &));
230 
231   ComplexPairTy EmitBinAdd(const BinOpInfo &Op);
232   ComplexPairTy EmitBinSub(const BinOpInfo &Op);
233   ComplexPairTy EmitBinMul(const BinOpInfo &Op);
234   ComplexPairTy EmitBinDiv(const BinOpInfo &Op);
235 
236   ComplexPairTy VisitBinAdd(const BinaryOperator *E) {
237     return EmitBinAdd(EmitBinOps(E));
238   }
239   ComplexPairTy VisitBinSub(const BinaryOperator *E) {
240     return EmitBinSub(EmitBinOps(E));
241   }
242   ComplexPairTy VisitBinMul(const BinaryOperator *E) {
243     return EmitBinMul(EmitBinOps(E));
244   }
245   ComplexPairTy VisitBinDiv(const BinaryOperator *E) {
246     return EmitBinDiv(EmitBinOps(E));
247   }
248 
249   // Compound assignments.
250   ComplexPairTy VisitBinAddAssign(const CompoundAssignOperator *E) {
251     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinAdd);
252   }
253   ComplexPairTy VisitBinSubAssign(const CompoundAssignOperator *E) {
254     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinSub);
255   }
256   ComplexPairTy VisitBinMulAssign(const CompoundAssignOperator *E) {
257     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinMul);
258   }
259   ComplexPairTy VisitBinDivAssign(const CompoundAssignOperator *E) {
260     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinDiv);
261   }
262 
263   // GCC rejects rem/and/or/xor for integer complex.
264   // Logical and/or always return int, never complex.
265 
266   // No comparisons produce a complex result.
267 
268   LValue EmitBinAssignLValue(const BinaryOperator *E,
269                              ComplexPairTy &Val);
270   ComplexPairTy VisitBinAssign     (const BinaryOperator *E);
271   ComplexPairTy VisitBinComma      (const BinaryOperator *E);
272 
273 
274   ComplexPairTy
275   VisitAbstractConditionalOperator(const AbstractConditionalOperator *CO);
276   ComplexPairTy VisitChooseExpr(ChooseExpr *CE);
277 
278   ComplexPairTy VisitInitListExpr(InitListExpr *E);
279 
280   ComplexPairTy VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
281     return EmitLoadOfLValue(E);
282   }
283 
284   ComplexPairTy VisitVAArgExpr(VAArgExpr *E);
285 
286   ComplexPairTy VisitAtomicExpr(AtomicExpr *E) {
287     return CGF.EmitAtomicExpr(E).getComplexVal();
288   }
289 };
290 }  // end anonymous namespace.
291 
292 //===----------------------------------------------------------------------===//
293 //                                Utilities
294 //===----------------------------------------------------------------------===//
295 
296 /// EmitLoadOfComplex - Given an RValue reference for a complex, emit code to
297 /// load the real and imaginary pieces, returning them as Real/Imag.
298 ComplexPairTy ComplexExprEmitter::EmitLoadOfComplex(llvm::Value *SrcPtr,
299                                                     bool isVolatile) {
300   llvm::Value *Real=0, *Imag=0;
301 
302   if (!IgnoreReal || isVolatile) {
303     llvm::Value *RealP = Builder.CreateStructGEP(SrcPtr, 0,
304                                                  SrcPtr->getName() + ".realp");
305     Real = Builder.CreateLoad(RealP, isVolatile, SrcPtr->getName() + ".real");
306   }
307 
308   if (!IgnoreImag || isVolatile) {
309     llvm::Value *ImagP = Builder.CreateStructGEP(SrcPtr, 1,
310                                                  SrcPtr->getName() + ".imagp");
311     Imag = Builder.CreateLoad(ImagP, isVolatile, SrcPtr->getName() + ".imag");
312   }
313   return ComplexPairTy(Real, Imag);
314 }
315 
316 /// EmitStoreOfComplex - Store the specified real/imag parts into the
317 /// specified value pointer.
318 void ComplexExprEmitter::EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *Ptr,
319                                             bool isVolatile) {
320   llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, "real");
321   llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, "imag");
322 
323   Builder.CreateStore(Val.first, RealPtr, isVolatile);
324   Builder.CreateStore(Val.second, ImagPtr, isVolatile);
325 }
326 
327 
328 
329 //===----------------------------------------------------------------------===//
330 //                            Visitor Methods
331 //===----------------------------------------------------------------------===//
332 
333 ComplexPairTy ComplexExprEmitter::VisitExpr(Expr *E) {
334   CGF.ErrorUnsupported(E, "complex expression");
335   llvm::Type *EltTy =
336   CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
337   llvm::Value *U = llvm::UndefValue::get(EltTy);
338   return ComplexPairTy(U, U);
339 }
340 
341 ComplexPairTy ComplexExprEmitter::
342 VisitImaginaryLiteral(const ImaginaryLiteral *IL) {
343   llvm::Value *Imag = CGF.EmitScalarExpr(IL->getSubExpr());
344   return ComplexPairTy(llvm::Constant::getNullValue(Imag->getType()), Imag);
345 }
346 
347 
348 ComplexPairTy ComplexExprEmitter::VisitCallExpr(const CallExpr *E) {
349   if (E->getCallReturnType()->isReferenceType())
350     return EmitLoadOfLValue(E);
351 
352   return CGF.EmitCallExpr(E).getComplexVal();
353 }
354 
355 ComplexPairTy ComplexExprEmitter::VisitStmtExpr(const StmtExpr *E) {
356   CodeGenFunction::StmtExprEvaluation eval(CGF);
357   return CGF.EmitCompoundStmt(*E->getSubStmt(), true).getComplexVal();
358 }
359 
360 /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
361 ComplexPairTy ComplexExprEmitter::EmitComplexToComplexCast(ComplexPairTy Val,
362                                                            QualType SrcType,
363                                                            QualType DestType) {
364   // Get the src/dest element type.
365   SrcType = SrcType->getAs<ComplexType>()->getElementType();
366   DestType = DestType->getAs<ComplexType>()->getElementType();
367 
368   // C99 6.3.1.6: When a value of complex type is converted to another
369   // complex type, both the real and imaginary parts follow the conversion
370   // rules for the corresponding real types.
371   Val.first = CGF.EmitScalarConversion(Val.first, SrcType, DestType);
372   Val.second = CGF.EmitScalarConversion(Val.second, SrcType, DestType);
373   return Val;
374 }
375 
376 ComplexPairTy ComplexExprEmitter::EmitCast(CastExpr::CastKind CK, Expr *Op,
377                                            QualType DestTy) {
378   switch (CK) {
379   case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!");
380 
381   // Atomic to non-atomic casts may be more than a no-op for some platforms and
382   // for some types.
383   case CK_AtomicToNonAtomic:
384   case CK_NonAtomicToAtomic:
385   case CK_NoOp:
386   case CK_LValueToRValue:
387   case CK_UserDefinedConversion:
388     return Visit(Op);
389 
390   case CK_LValueBitCast: {
391     llvm::Value *V = CGF.EmitLValue(Op).getAddress();
392     V = Builder.CreateBitCast(V,
393                     CGF.ConvertType(CGF.getContext().getPointerType(DestTy)));
394     // FIXME: Are the qualifiers correct here?
395     return EmitLoadOfComplex(V, DestTy.isVolatileQualified());
396   }
397 
398   case CK_BitCast:
399   case CK_BaseToDerived:
400   case CK_DerivedToBase:
401   case CK_UncheckedDerivedToBase:
402   case CK_Dynamic:
403   case CK_ToUnion:
404   case CK_ArrayToPointerDecay:
405   case CK_FunctionToPointerDecay:
406   case CK_NullToPointer:
407   case CK_NullToMemberPointer:
408   case CK_BaseToDerivedMemberPointer:
409   case CK_DerivedToBaseMemberPointer:
410   case CK_MemberPointerToBoolean:
411   case CK_ReinterpretMemberPointer:
412   case CK_ConstructorConversion:
413   case CK_IntegralToPointer:
414   case CK_PointerToIntegral:
415   case CK_PointerToBoolean:
416   case CK_ToVoid:
417   case CK_VectorSplat:
418   case CK_IntegralCast:
419   case CK_IntegralToBoolean:
420   case CK_IntegralToFloating:
421   case CK_FloatingToIntegral:
422   case CK_FloatingToBoolean:
423   case CK_FloatingCast:
424   case CK_CPointerToObjCPointerCast:
425   case CK_BlockPointerToObjCPointerCast:
426   case CK_AnyPointerToBlockPointerCast:
427   case CK_ObjCObjectLValueCast:
428   case CK_FloatingComplexToReal:
429   case CK_FloatingComplexToBoolean:
430   case CK_IntegralComplexToReal:
431   case CK_IntegralComplexToBoolean:
432   case CK_ARCProduceObject:
433   case CK_ARCConsumeObject:
434   case CK_ARCReclaimReturnedObject:
435   case CK_ARCExtendBlockObject:
436   case CK_CopyAndAutoreleaseBlockObject:
437     llvm_unreachable("invalid cast kind for complex value");
438 
439   case CK_FloatingRealToComplex:
440   case CK_IntegralRealToComplex: {
441     llvm::Value *Elt = CGF.EmitScalarExpr(Op);
442 
443     // Convert the input element to the element type of the complex.
444     DestTy = DestTy->getAs<ComplexType>()->getElementType();
445     Elt = CGF.EmitScalarConversion(Elt, Op->getType(), DestTy);
446 
447     // Return (realval, 0).
448     return ComplexPairTy(Elt, llvm::Constant::getNullValue(Elt->getType()));
449   }
450 
451   case CK_FloatingComplexCast:
452   case CK_FloatingComplexToIntegralComplex:
453   case CK_IntegralComplexCast:
454   case CK_IntegralComplexToFloatingComplex:
455     return EmitComplexToComplexCast(Visit(Op), Op->getType(), DestTy);
456   }
457 
458   llvm_unreachable("unknown cast resulting in complex value");
459 }
460 
461 ComplexPairTy ComplexExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
462   TestAndClearIgnoreReal();
463   TestAndClearIgnoreImag();
464   ComplexPairTy Op = Visit(E->getSubExpr());
465 
466   llvm::Value *ResR, *ResI;
467   if (Op.first->getType()->isFloatingPointTy()) {
468     ResR = Builder.CreateFNeg(Op.first,  "neg.r");
469     ResI = Builder.CreateFNeg(Op.second, "neg.i");
470   } else {
471     ResR = Builder.CreateNeg(Op.first,  "neg.r");
472     ResI = Builder.CreateNeg(Op.second, "neg.i");
473   }
474   return ComplexPairTy(ResR, ResI);
475 }
476 
477 ComplexPairTy ComplexExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
478   TestAndClearIgnoreReal();
479   TestAndClearIgnoreImag();
480   // ~(a+ib) = a + i*-b
481   ComplexPairTy Op = Visit(E->getSubExpr());
482   llvm::Value *ResI;
483   if (Op.second->getType()->isFloatingPointTy())
484     ResI = Builder.CreateFNeg(Op.second, "conj.i");
485   else
486     ResI = Builder.CreateNeg(Op.second, "conj.i");
487 
488   return ComplexPairTy(Op.first, ResI);
489 }
490 
491 ComplexPairTy ComplexExprEmitter::EmitBinAdd(const BinOpInfo &Op) {
492   llvm::Value *ResR, *ResI;
493 
494   if (Op.LHS.first->getType()->isFloatingPointTy()) {
495     ResR = Builder.CreateFAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
496     ResI = Builder.CreateFAdd(Op.LHS.second, Op.RHS.second, "add.i");
497   } else {
498     ResR = Builder.CreateAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
499     ResI = Builder.CreateAdd(Op.LHS.second, Op.RHS.second, "add.i");
500   }
501   return ComplexPairTy(ResR, ResI);
502 }
503 
504 ComplexPairTy ComplexExprEmitter::EmitBinSub(const BinOpInfo &Op) {
505   llvm::Value *ResR, *ResI;
506   if (Op.LHS.first->getType()->isFloatingPointTy()) {
507     ResR = Builder.CreateFSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
508     ResI = Builder.CreateFSub(Op.LHS.second, Op.RHS.second, "sub.i");
509   } else {
510     ResR = Builder.CreateSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
511     ResI = Builder.CreateSub(Op.LHS.second, Op.RHS.second, "sub.i");
512   }
513   return ComplexPairTy(ResR, ResI);
514 }
515 
516 
517 ComplexPairTy ComplexExprEmitter::EmitBinMul(const BinOpInfo &Op) {
518   using llvm::Value;
519   Value *ResR, *ResI;
520 
521   if (Op.LHS.first->getType()->isFloatingPointTy()) {
522     Value *ResRl = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul.rl");
523     Value *ResRr = Builder.CreateFMul(Op.LHS.second, Op.RHS.second,"mul.rr");
524     ResR  = Builder.CreateFSub(ResRl, ResRr, "mul.r");
525 
526     Value *ResIl = Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul.il");
527     Value *ResIr = Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul.ir");
528     ResI  = Builder.CreateFAdd(ResIl, ResIr, "mul.i");
529   } else {
530     Value *ResRl = Builder.CreateMul(Op.LHS.first, Op.RHS.first, "mul.rl");
531     Value *ResRr = Builder.CreateMul(Op.LHS.second, Op.RHS.second,"mul.rr");
532     ResR  = Builder.CreateSub(ResRl, ResRr, "mul.r");
533 
534     Value *ResIl = Builder.CreateMul(Op.LHS.second, Op.RHS.first, "mul.il");
535     Value *ResIr = Builder.CreateMul(Op.LHS.first, Op.RHS.second, "mul.ir");
536     ResI  = Builder.CreateAdd(ResIl, ResIr, "mul.i");
537   }
538   return ComplexPairTy(ResR, ResI);
539 }
540 
541 ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
542   llvm::Value *LHSr = Op.LHS.first, *LHSi = Op.LHS.second;
543   llvm::Value *RHSr = Op.RHS.first, *RHSi = Op.RHS.second;
544 
545 
546   llvm::Value *DSTr, *DSTi;
547   if (Op.LHS.first->getType()->isFloatingPointTy()) {
548     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
549     llvm::Value *Tmp1 = Builder.CreateFMul(LHSr, RHSr); // a*c
550     llvm::Value *Tmp2 = Builder.CreateFMul(LHSi, RHSi); // b*d
551     llvm::Value *Tmp3 = Builder.CreateFAdd(Tmp1, Tmp2); // ac+bd
552 
553     llvm::Value *Tmp4 = Builder.CreateFMul(RHSr, RHSr); // c*c
554     llvm::Value *Tmp5 = Builder.CreateFMul(RHSi, RHSi); // d*d
555     llvm::Value *Tmp6 = Builder.CreateFAdd(Tmp4, Tmp5); // cc+dd
556 
557     llvm::Value *Tmp7 = Builder.CreateFMul(LHSi, RHSr); // b*c
558     llvm::Value *Tmp8 = Builder.CreateFMul(LHSr, RHSi); // a*d
559     llvm::Value *Tmp9 = Builder.CreateFSub(Tmp7, Tmp8); // bc-ad
560 
561     DSTr = Builder.CreateFDiv(Tmp3, Tmp6);
562     DSTi = Builder.CreateFDiv(Tmp9, Tmp6);
563   } else {
564     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
565     llvm::Value *Tmp1 = Builder.CreateMul(LHSr, RHSr); // a*c
566     llvm::Value *Tmp2 = Builder.CreateMul(LHSi, RHSi); // b*d
567     llvm::Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2); // ac+bd
568 
569     llvm::Value *Tmp4 = Builder.CreateMul(RHSr, RHSr); // c*c
570     llvm::Value *Tmp5 = Builder.CreateMul(RHSi, RHSi); // d*d
571     llvm::Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5); // cc+dd
572 
573     llvm::Value *Tmp7 = Builder.CreateMul(LHSi, RHSr); // b*c
574     llvm::Value *Tmp8 = Builder.CreateMul(LHSr, RHSi); // a*d
575     llvm::Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8); // bc-ad
576 
577     if (Op.Ty->getAs<ComplexType>()->getElementType()->isUnsignedIntegerType()) {
578       DSTr = Builder.CreateUDiv(Tmp3, Tmp6);
579       DSTi = Builder.CreateUDiv(Tmp9, Tmp6);
580     } else {
581       DSTr = Builder.CreateSDiv(Tmp3, Tmp6);
582       DSTi = Builder.CreateSDiv(Tmp9, Tmp6);
583     }
584   }
585 
586   return ComplexPairTy(DSTr, DSTi);
587 }
588 
589 ComplexExprEmitter::BinOpInfo
590 ComplexExprEmitter::EmitBinOps(const BinaryOperator *E) {
591   TestAndClearIgnoreReal();
592   TestAndClearIgnoreImag();
593   BinOpInfo Ops;
594   Ops.LHS = Visit(E->getLHS());
595   Ops.RHS = Visit(E->getRHS());
596   Ops.Ty = E->getType();
597   return Ops;
598 }
599 
600 
601 LValue ComplexExprEmitter::
602 EmitCompoundAssignLValue(const CompoundAssignOperator *E,
603           ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&),
604                          ComplexPairTy &Val) {
605   TestAndClearIgnoreReal();
606   TestAndClearIgnoreImag();
607   QualType LHSTy = E->getLHS()->getType();
608 
609   BinOpInfo OpInfo;
610 
611   // Load the RHS and LHS operands.
612   // __block variables need to have the rhs evaluated first, plus this should
613   // improve codegen a little.
614   OpInfo.Ty = E->getComputationResultType();
615 
616   // The RHS should have been converted to the computation type.
617   assert(OpInfo.Ty->isAnyComplexType());
618   assert(CGF.getContext().hasSameUnqualifiedType(OpInfo.Ty,
619                                                  E->getRHS()->getType()));
620   OpInfo.RHS = Visit(E->getRHS());
621 
622   LValue LHS = CGF.EmitLValue(E->getLHS());
623 
624   // Load from the l-value.
625   ComplexPairTy LHSComplexPair = EmitLoadOfLValue(LHS);
626 
627   OpInfo.LHS = EmitComplexToComplexCast(LHSComplexPair, LHSTy, OpInfo.Ty);
628 
629   // Expand the binary operator.
630   ComplexPairTy Result = (this->*Func)(OpInfo);
631 
632   // Truncate the result back to the LHS type.
633   Result = EmitComplexToComplexCast(Result, OpInfo.Ty, LHSTy);
634   Val = Result;
635 
636   // Store the result value into the LHS lvalue.
637   EmitStoreThroughLValue(Result, LHS);
638 
639   return LHS;
640 }
641 
642 // Compound assignments.
643 ComplexPairTy ComplexExprEmitter::
644 EmitCompoundAssign(const CompoundAssignOperator *E,
645                    ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&)){
646   ComplexPairTy Val;
647   LValue LV = EmitCompoundAssignLValue(E, Func, Val);
648 
649   // The result of an assignment in C is the assigned r-value.
650   if (!CGF.getContext().getLangOptions().CPlusPlus)
651     return Val;
652 
653   // If the lvalue is non-volatile, return the computed value of the assignment.
654   if (!LV.isVolatileQualified())
655     return Val;
656 
657   return EmitLoadOfComplex(LV.getAddress(), LV.isVolatileQualified());
658 }
659 
660 LValue ComplexExprEmitter::EmitBinAssignLValue(const BinaryOperator *E,
661                                                ComplexPairTy &Val) {
662   assert(CGF.getContext().hasSameUnqualifiedType(E->getLHS()->getType(),
663                                                  E->getRHS()->getType()) &&
664          "Invalid assignment");
665   TestAndClearIgnoreReal();
666   TestAndClearIgnoreImag();
667 
668   // Emit the RHS.  __block variables need the RHS evaluated first.
669   Val = Visit(E->getRHS());
670 
671   // Compute the address to store into.
672   LValue LHS = CGF.EmitLValue(E->getLHS());
673 
674   // Store the result value into the LHS lvalue.
675   EmitStoreThroughLValue(Val, LHS);
676 
677   return LHS;
678 }
679 
680 ComplexPairTy ComplexExprEmitter::VisitBinAssign(const BinaryOperator *E) {
681   ComplexPairTy Val;
682   LValue LV = EmitBinAssignLValue(E, Val);
683 
684   // The result of an assignment in C is the assigned r-value.
685   if (!CGF.getContext().getLangOptions().CPlusPlus)
686     return Val;
687 
688   // If the lvalue is non-volatile, return the computed value of the assignment.
689   if (!LV.isVolatileQualified())
690     return Val;
691 
692   return EmitLoadOfComplex(LV.getAddress(), LV.isVolatileQualified());
693 }
694 
695 ComplexPairTy ComplexExprEmitter::VisitBinComma(const BinaryOperator *E) {
696   CGF.EmitIgnoredExpr(E->getLHS());
697   return Visit(E->getRHS());
698 }
699 
700 ComplexPairTy ComplexExprEmitter::
701 VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) {
702   TestAndClearIgnoreReal();
703   TestAndClearIgnoreImag();
704   llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
705   llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
706   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
707 
708   // Bind the common expression if necessary.
709   CodeGenFunction::OpaqueValueMapping binding(CGF, E);
710 
711   CodeGenFunction::ConditionalEvaluation eval(CGF);
712   CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock);
713 
714   eval.begin(CGF);
715   CGF.EmitBlock(LHSBlock);
716   ComplexPairTy LHS = Visit(E->getTrueExpr());
717   LHSBlock = Builder.GetInsertBlock();
718   CGF.EmitBranch(ContBlock);
719   eval.end(CGF);
720 
721   eval.begin(CGF);
722   CGF.EmitBlock(RHSBlock);
723   ComplexPairTy RHS = Visit(E->getFalseExpr());
724   RHSBlock = Builder.GetInsertBlock();
725   CGF.EmitBlock(ContBlock);
726   eval.end(CGF);
727 
728   // Create a PHI node for the real part.
729   llvm::PHINode *RealPN = Builder.CreatePHI(LHS.first->getType(), 2, "cond.r");
730   RealPN->addIncoming(LHS.first, LHSBlock);
731   RealPN->addIncoming(RHS.first, RHSBlock);
732 
733   // Create a PHI node for the imaginary part.
734   llvm::PHINode *ImagPN = Builder.CreatePHI(LHS.first->getType(), 2, "cond.i");
735   ImagPN->addIncoming(LHS.second, LHSBlock);
736   ImagPN->addIncoming(RHS.second, RHSBlock);
737 
738   return ComplexPairTy(RealPN, ImagPN);
739 }
740 
741 ComplexPairTy ComplexExprEmitter::VisitChooseExpr(ChooseExpr *E) {
742   return Visit(E->getChosenSubExpr(CGF.getContext()));
743 }
744 
745 ComplexPairTy ComplexExprEmitter::VisitInitListExpr(InitListExpr *E) {
746     bool Ignore = TestAndClearIgnoreReal();
747     (void)Ignore;
748     assert (Ignore == false && "init list ignored");
749     Ignore = TestAndClearIgnoreImag();
750     (void)Ignore;
751     assert (Ignore == false && "init list ignored");
752 
753   if (E->getNumInits() == 2) {
754     llvm::Value *Real = CGF.EmitScalarExpr(E->getInit(0));
755     llvm::Value *Imag = CGF.EmitScalarExpr(E->getInit(1));
756     return ComplexPairTy(Real, Imag);
757   } else if (E->getNumInits() == 1) {
758     return Visit(E->getInit(0));
759   }
760 
761   // Empty init list intializes to null
762   assert(E->getNumInits() == 0 && "Unexpected number of inits");
763   QualType Ty = E->getType()->getAs<ComplexType>()->getElementType();
764   llvm::Type* LTy = CGF.ConvertType(Ty);
765   llvm::Value* zeroConstant = llvm::Constant::getNullValue(LTy);
766   return ComplexPairTy(zeroConstant, zeroConstant);
767 }
768 
769 ComplexPairTy ComplexExprEmitter::VisitVAArgExpr(VAArgExpr *E) {
770   llvm::Value *ArgValue = CGF.EmitVAListRef(E->getSubExpr());
771   llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, E->getType());
772 
773   if (!ArgPtr) {
774     CGF.ErrorUnsupported(E, "complex va_arg expression");
775     llvm::Type *EltTy =
776       CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
777     llvm::Value *U = llvm::UndefValue::get(EltTy);
778     return ComplexPairTy(U, U);
779   }
780 
781   // FIXME Volatility.
782   return EmitLoadOfComplex(ArgPtr, false);
783 }
784 
785 //===----------------------------------------------------------------------===//
786 //                         Entry Point into this File
787 //===----------------------------------------------------------------------===//
788 
789 /// EmitComplexExpr - Emit the computation of the specified expression of
790 /// complex type, ignoring the result.
791 ComplexPairTy CodeGenFunction::EmitComplexExpr(const Expr *E, bool IgnoreReal,
792                                                bool IgnoreImag) {
793   assert(E && E->getType()->isAnyComplexType() &&
794          "Invalid complex expression to emit");
795 
796   return ComplexExprEmitter(*this, IgnoreReal, IgnoreImag)
797     .Visit(const_cast<Expr*>(E));
798 }
799 
800 /// EmitComplexExprIntoAddr - Emit the computation of the specified expression
801 /// of complex type, storing into the specified Value*.
802 void CodeGenFunction::EmitComplexExprIntoAddr(const Expr *E,
803                                               llvm::Value *DestAddr,
804                                               bool DestIsVolatile) {
805   assert(E && E->getType()->isAnyComplexType() &&
806          "Invalid complex expression to emit");
807   ComplexExprEmitter Emitter(*this);
808   ComplexPairTy Val = Emitter.Visit(const_cast<Expr*>(E));
809   Emitter.EmitStoreOfComplex(Val, DestAddr, DestIsVolatile);
810 }
811 
812 /// StoreComplexToAddr - Store a complex number into the specified address.
813 void CodeGenFunction::StoreComplexToAddr(ComplexPairTy V,
814                                          llvm::Value *DestAddr,
815                                          bool DestIsVolatile) {
816   ComplexExprEmitter(*this).EmitStoreOfComplex(V, DestAddr, DestIsVolatile);
817 }
818 
819 /// LoadComplexFromAddr - Load a complex number from the specified address.
820 ComplexPairTy CodeGenFunction::LoadComplexFromAddr(llvm::Value *SrcAddr,
821                                                    bool SrcIsVolatile) {
822   return ComplexExprEmitter(*this).EmitLoadOfComplex(SrcAddr, SrcIsVolatile);
823 }
824 
825 LValue CodeGenFunction::EmitComplexAssignmentLValue(const BinaryOperator *E) {
826   assert(E->getOpcode() == BO_Assign);
827   ComplexPairTy Val; // ignored
828   return ComplexExprEmitter(*this).EmitBinAssignLValue(E, Val);
829 }
830 
831 LValue CodeGenFunction::
832 EmitComplexCompoundAssignmentLValue(const CompoundAssignOperator *E) {
833   ComplexPairTy(ComplexExprEmitter::*Op)(const ComplexExprEmitter::BinOpInfo &);
834   switch (E->getOpcode()) {
835   case BO_MulAssign: Op = &ComplexExprEmitter::EmitBinMul; break;
836   case BO_DivAssign: Op = &ComplexExprEmitter::EmitBinDiv; break;
837   case BO_SubAssign: Op = &ComplexExprEmitter::EmitBinSub; break;
838   case BO_AddAssign: Op = &ComplexExprEmitter::EmitBinAdd; break;
839 
840   default:
841     llvm_unreachable("unexpected complex compound assignment");
842   }
843 
844   ComplexPairTy Val; // ignored
845   return ComplexExprEmitter(*this).EmitCompoundAssignLValue(E, Op, Val);
846 }
847