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