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   // True if we should ignore the value of a=b
39   bool IgnoreRealAssign;
40   bool IgnoreImagAssign;
41 public:
42   ComplexExprEmitter(CodeGenFunction &cgf, bool ir=false, bool ii=false,
43                      bool irn=false, bool iin=false)
44     : CGF(cgf), Builder(CGF.Builder), IgnoreReal(ir), IgnoreImag(ii),
45     IgnoreRealAssign(irn), IgnoreImagAssign(iin) {
46   }
47 
48 
49   //===--------------------------------------------------------------------===//
50   //                               Utilities
51   //===--------------------------------------------------------------------===//
52 
53   bool TestAndClearIgnoreReal() {
54     bool I = IgnoreReal;
55     IgnoreReal = false;
56     return I;
57   }
58   bool TestAndClearIgnoreImag() {
59     bool I = IgnoreImag;
60     IgnoreImag = false;
61     return I;
62   }
63   bool TestAndClearIgnoreRealAssign() {
64     bool I = IgnoreRealAssign;
65     IgnoreRealAssign = false;
66     return I;
67   }
68   bool TestAndClearIgnoreImagAssign() {
69     bool I = IgnoreImagAssign;
70     IgnoreImagAssign = false;
71     return I;
72   }
73 
74   /// EmitLoadOfLValue - Given an expression with complex type that represents a
75   /// value l-value, this method emits the address of the l-value, then loads
76   /// and returns the result.
77   ComplexPairTy EmitLoadOfLValue(const Expr *E) {
78     LValue LV = CGF.EmitLValue(E);
79     if (LV.isSimple())
80       return EmitLoadOfComplex(LV.getAddress(), LV.isVolatileQualified());
81 
82     if (LV.isPropertyRef())
83       return CGF.EmitObjCPropertyGet(LV.getPropertyRefExpr()).getComplexVal();
84 
85     assert(LV.isKVCRef() && "Unknown LValue type!");
86     return CGF.EmitObjCPropertyGet(LV.getKVCRefExpr()).getComplexVal();
87   }
88 
89   /// EmitLoadOfComplex - Given a pointer to a complex value, emit code to load
90   /// the real and imaginary pieces.
91   ComplexPairTy EmitLoadOfComplex(llvm::Value *SrcPtr, bool isVolatile);
92 
93   /// EmitStoreOfComplex - Store the specified real/imag parts into the
94   /// specified value pointer.
95   void EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *ResPtr, bool isVol);
96 
97   /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
98   ComplexPairTy EmitComplexToComplexCast(ComplexPairTy Val, QualType SrcType,
99                                          QualType DestType);
100 
101   //===--------------------------------------------------------------------===//
102   //                            Visitor Methods
103   //===--------------------------------------------------------------------===//
104 
105   ComplexPairTy Visit(Expr *E) {
106     llvm::DenseMap<const Expr *, ComplexPairTy>::iterator I =
107       CGF.ConditionalSaveComplexExprs.find(E);
108     if (I != CGF.ConditionalSaveComplexExprs.end())
109       return I->second;
110 
111       return StmtVisitor<ComplexExprEmitter, ComplexPairTy>::Visit(E);
112   }
113 
114   ComplexPairTy VisitStmt(Stmt *S) {
115     S->dump(CGF.getContext().getSourceManager());
116     assert(0 && "Stmt can't have complex result type!");
117     return ComplexPairTy();
118   }
119   ComplexPairTy VisitExpr(Expr *S);
120   ComplexPairTy VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr());}
121   ComplexPairTy VisitImaginaryLiteral(const ImaginaryLiteral *IL);
122 
123   // l-values.
124   ComplexPairTy VisitDeclRefExpr(const Expr *E) { return EmitLoadOfLValue(E); }
125   ComplexPairTy VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
126     return EmitLoadOfLValue(E);
127   }
128   ComplexPairTy VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) {
129     return EmitLoadOfLValue(E);
130   }
131   ComplexPairTy VisitObjCImplicitSetterGetterRefExpr(
132                                ObjCImplicitSetterGetterRefExpr *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 
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     TestAndClearIgnoreRealAssign();
178     TestAndClearIgnoreImagAssign();
179     return Visit(E->getSubExpr());
180   }
181   ComplexPairTy VisitUnaryMinus    (const UnaryOperator *E);
182   ComplexPairTy VisitUnaryNot      (const UnaryOperator *E);
183   // LNot,Real,Imag never return complex.
184   ComplexPairTy VisitUnaryExtension(const UnaryOperator *E) {
185     return Visit(E->getSubExpr());
186   }
187   ComplexPairTy VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
188     return Visit(DAE->getExpr());
189   }
190   ComplexPairTy VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) {
191     return CGF.EmitCXXExprWithTemporaries(E).getComplexVal();
192   }
193   ComplexPairTy VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E) {
194     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
195     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
196     llvm::Constant *Null = llvm::Constant::getNullValue(CGF.ConvertType(Elem));
197     return ComplexPairTy(Null, Null);
198   }
199   ComplexPairTy VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
200     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
201     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
202     llvm::Constant *Null =
203                        llvm::Constant::getNullValue(CGF.ConvertType(Elem));
204     return ComplexPairTy(Null, Null);
205   }
206 
207   struct BinOpInfo {
208     ComplexPairTy LHS;
209     ComplexPairTy RHS;
210     QualType Ty;  // Computation Type.
211   };
212 
213   BinOpInfo EmitBinOps(const BinaryOperator *E);
214   ComplexPairTy EmitCompoundAssign(const CompoundAssignOperator *E,
215                                    ComplexPairTy (ComplexExprEmitter::*Func)
216                                    (const BinOpInfo &));
217 
218   ComplexPairTy EmitBinAdd(const BinOpInfo &Op);
219   ComplexPairTy EmitBinSub(const BinOpInfo &Op);
220   ComplexPairTy EmitBinMul(const BinOpInfo &Op);
221   ComplexPairTy EmitBinDiv(const BinOpInfo &Op);
222 
223   ComplexPairTy VisitBinMul(const BinaryOperator *E) {
224     return EmitBinMul(EmitBinOps(E));
225   }
226   ComplexPairTy VisitBinAdd(const BinaryOperator *E) {
227     return EmitBinAdd(EmitBinOps(E));
228   }
229   ComplexPairTy VisitBinSub(const BinaryOperator *E) {
230     return EmitBinSub(EmitBinOps(E));
231   }
232   ComplexPairTy VisitBinDiv(const BinaryOperator *E) {
233     return EmitBinDiv(EmitBinOps(E));
234   }
235 
236   // Compound assignments.
237   ComplexPairTy VisitBinAddAssign(const CompoundAssignOperator *E) {
238     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinAdd);
239   }
240   ComplexPairTy VisitBinSubAssign(const CompoundAssignOperator *E) {
241     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinSub);
242   }
243   ComplexPairTy VisitBinMulAssign(const CompoundAssignOperator *E) {
244     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinMul);
245   }
246   ComplexPairTy VisitBinDivAssign(const CompoundAssignOperator *E) {
247     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinDiv);
248   }
249 
250   // GCC rejects rem/and/or/xor for integer complex.
251   // Logical and/or always return int, never complex.
252 
253   // No comparisons produce a complex result.
254   ComplexPairTy VisitBinAssign     (const BinaryOperator *E);
255   ComplexPairTy VisitBinComma      (const BinaryOperator *E);
256 
257 
258   ComplexPairTy VisitConditionalOperator(const ConditionalOperator *CO);
259   ComplexPairTy VisitChooseExpr(ChooseExpr *CE);
260 
261   ComplexPairTy VisitInitListExpr(InitListExpr *E);
262 
263   ComplexPairTy VisitVAArgExpr(VAArgExpr *E);
264 };
265 }  // end anonymous namespace.
266 
267 //===----------------------------------------------------------------------===//
268 //                                Utilities
269 //===----------------------------------------------------------------------===//
270 
271 /// EmitLoadOfComplex - Given an RValue reference for a complex, emit code to
272 /// load the real and imaginary pieces, returning them as Real/Imag.
273 ComplexPairTy ComplexExprEmitter::EmitLoadOfComplex(llvm::Value *SrcPtr,
274                                                     bool isVolatile) {
275   llvm::Value *Real=0, *Imag=0;
276 
277   // FIXME: we should really not be suppressing volatile loads.
278 
279   if (!IgnoreReal) {
280     llvm::Value *RealP = Builder.CreateStructGEP(SrcPtr, 0,
281                                                  SrcPtr->getName() + ".realp");
282     Real = Builder.CreateLoad(RealP, isVolatile, SrcPtr->getName() + ".real");
283   }
284 
285   if (!IgnoreImag) {
286     llvm::Value *ImagP = Builder.CreateStructGEP(SrcPtr, 1,
287                                                  SrcPtr->getName() + ".imagp");
288     Imag = Builder.CreateLoad(ImagP, isVolatile, SrcPtr->getName() + ".imag");
289   }
290   return ComplexPairTy(Real, Imag);
291 }
292 
293 /// EmitStoreOfComplex - Store the specified real/imag parts into the
294 /// specified value pointer.
295 void ComplexExprEmitter::EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *Ptr,
296                                             bool isVolatile) {
297   llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, "real");
298   llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, "imag");
299 
300   Builder.CreateStore(Val.first, RealPtr, isVolatile);
301   Builder.CreateStore(Val.second, ImagPtr, isVolatile);
302 }
303 
304 
305 
306 //===----------------------------------------------------------------------===//
307 //                            Visitor Methods
308 //===----------------------------------------------------------------------===//
309 
310 ComplexPairTy ComplexExprEmitter::VisitExpr(Expr *E) {
311   CGF.ErrorUnsupported(E, "complex expression");
312   const llvm::Type *EltTy =
313     CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
314   llvm::Value *U = llvm::UndefValue::get(EltTy);
315   return ComplexPairTy(U, U);
316 }
317 
318 ComplexPairTy ComplexExprEmitter::
319 VisitImaginaryLiteral(const ImaginaryLiteral *IL) {
320   llvm::Value *Imag = CGF.EmitScalarExpr(IL->getSubExpr());
321   return
322         ComplexPairTy(llvm::Constant::getNullValue(Imag->getType()), Imag);
323 }
324 
325 
326 ComplexPairTy ComplexExprEmitter::VisitCallExpr(const CallExpr *E) {
327   if (E->getCallReturnType()->isReferenceType())
328     return EmitLoadOfLValue(E);
329 
330   return CGF.EmitCallExpr(E).getComplexVal();
331 }
332 
333 ComplexPairTy ComplexExprEmitter::VisitStmtExpr(const StmtExpr *E) {
334   return CGF.EmitCompoundStmt(*E->getSubStmt(), true).getComplexVal();
335 }
336 
337 /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
338 ComplexPairTy ComplexExprEmitter::EmitComplexToComplexCast(ComplexPairTy Val,
339                                                            QualType SrcType,
340                                                            QualType DestType) {
341   // Get the src/dest element type.
342   SrcType = SrcType->getAs<ComplexType>()->getElementType();
343   DestType = DestType->getAs<ComplexType>()->getElementType();
344 
345   // C99 6.3.1.6: When a value of complex type is converted to another
346   // complex type, both the real and imaginary parts follow the conversion
347   // rules for the corresponding real types.
348   Val.first = CGF.EmitScalarConversion(Val.first, SrcType, DestType);
349   Val.second = CGF.EmitScalarConversion(Val.second, SrcType, DestType);
350   return Val;
351 }
352 
353 ComplexPairTy ComplexExprEmitter::EmitCast(CastExpr::CastKind CK, Expr *Op,
354                                            QualType DestTy) {
355   // FIXME: this should be based off of the CastKind.
356 
357   // Two cases here: cast from (complex to complex) and (scalar to complex).
358   if (Op->getType()->isAnyComplexType())
359     return EmitComplexToComplexCast(Visit(Op), Op->getType(), DestTy);
360 
361   // FIXME: We should be looking at all of the cast kinds here, not
362   // cherry-picking the ones we have test cases for.
363   if (CK == CK_LValueBitCast) {
364     llvm::Value *V = CGF.EmitLValue(Op).getAddress();
365     V = Builder.CreateBitCast(V,
366                       CGF.ConvertType(CGF.getContext().getPointerType(DestTy)));
367     // FIXME: Are the qualifiers correct here?
368     return EmitLoadOfComplex(V, DestTy.isVolatileQualified());
369   }
370 
371   // C99 6.3.1.7: When a value of real type is converted to a complex type, the
372   // real part of the complex result value is determined by the rules of
373   // conversion to the corresponding real type and the imaginary part of the
374   // complex result value is a positive zero or an unsigned zero.
375   llvm::Value *Elt = CGF.EmitScalarExpr(Op);
376 
377   // Convert the input element to the element type of the complex.
378   DestTy = DestTy->getAs<ComplexType>()->getElementType();
379   Elt = CGF.EmitScalarConversion(Elt, Op->getType(), DestTy);
380 
381   // Return (realval, 0).
382   return ComplexPairTy(Elt, llvm::Constant::getNullValue(Elt->getType()));
383 }
384 
385 ComplexPairTy ComplexExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
386   TestAndClearIgnoreReal();
387   TestAndClearIgnoreImag();
388   TestAndClearIgnoreRealAssign();
389   TestAndClearIgnoreImagAssign();
390   ComplexPairTy Op = Visit(E->getSubExpr());
391 
392   llvm::Value *ResR, *ResI;
393   if (Op.first->getType()->isFloatingPointTy()) {
394     ResR = Builder.CreateFNeg(Op.first,  "neg.r");
395     ResI = Builder.CreateFNeg(Op.second, "neg.i");
396   } else {
397     ResR = Builder.CreateNeg(Op.first,  "neg.r");
398     ResI = Builder.CreateNeg(Op.second, "neg.i");
399   }
400   return ComplexPairTy(ResR, ResI);
401 }
402 
403 ComplexPairTy ComplexExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
404   TestAndClearIgnoreReal();
405   TestAndClearIgnoreImag();
406   TestAndClearIgnoreRealAssign();
407   TestAndClearIgnoreImagAssign();
408   // ~(a+ib) = a + i*-b
409   ComplexPairTy Op = Visit(E->getSubExpr());
410   llvm::Value *ResI;
411   if (Op.second->getType()->isFloatingPointTy())
412     ResI = Builder.CreateFNeg(Op.second, "conj.i");
413   else
414     ResI = Builder.CreateNeg(Op.second, "conj.i");
415 
416   return ComplexPairTy(Op.first, ResI);
417 }
418 
419 ComplexPairTy ComplexExprEmitter::EmitBinAdd(const BinOpInfo &Op) {
420   llvm::Value *ResR, *ResI;
421 
422   if (Op.LHS.first->getType()->isFloatingPointTy()) {
423     ResR = Builder.CreateFAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
424     ResI = Builder.CreateFAdd(Op.LHS.second, Op.RHS.second, "add.i");
425   } else {
426     ResR = Builder.CreateAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
427     ResI = Builder.CreateAdd(Op.LHS.second, Op.RHS.second, "add.i");
428   }
429   return ComplexPairTy(ResR, ResI);
430 }
431 
432 ComplexPairTy ComplexExprEmitter::EmitBinSub(const BinOpInfo &Op) {
433   llvm::Value *ResR, *ResI;
434   if (Op.LHS.first->getType()->isFloatingPointTy()) {
435     ResR = Builder.CreateFSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
436     ResI = Builder.CreateFSub(Op.LHS.second, Op.RHS.second, "sub.i");
437   } else {
438     ResR = Builder.CreateSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
439     ResI = Builder.CreateSub(Op.LHS.second, Op.RHS.second, "sub.i");
440   }
441   return ComplexPairTy(ResR, ResI);
442 }
443 
444 
445 ComplexPairTy ComplexExprEmitter::EmitBinMul(const BinOpInfo &Op) {
446   using llvm::Value;
447   Value *ResR, *ResI;
448 
449   if (Op.LHS.first->getType()->isFloatingPointTy()) {
450     Value *ResRl = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul.rl");
451     Value *ResRr = Builder.CreateFMul(Op.LHS.second, Op.RHS.second,"mul.rr");
452     ResR  = Builder.CreateFSub(ResRl, ResRr, "mul.r");
453 
454     Value *ResIl = Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul.il");
455     Value *ResIr = Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul.ir");
456     ResI  = Builder.CreateFAdd(ResIl, ResIr, "mul.i");
457   } else {
458     Value *ResRl = Builder.CreateMul(Op.LHS.first, Op.RHS.first, "mul.rl");
459     Value *ResRr = Builder.CreateMul(Op.LHS.second, Op.RHS.second,"mul.rr");
460     ResR  = Builder.CreateSub(ResRl, ResRr, "mul.r");
461 
462     Value *ResIl = Builder.CreateMul(Op.LHS.second, Op.RHS.first, "mul.il");
463     Value *ResIr = Builder.CreateMul(Op.LHS.first, Op.RHS.second, "mul.ir");
464     ResI  = Builder.CreateAdd(ResIl, ResIr, "mul.i");
465   }
466   return ComplexPairTy(ResR, ResI);
467 }
468 
469 ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
470   llvm::Value *LHSr = Op.LHS.first, *LHSi = Op.LHS.second;
471   llvm::Value *RHSr = Op.RHS.first, *RHSi = Op.RHS.second;
472 
473 
474   llvm::Value *DSTr, *DSTi;
475   if (Op.LHS.first->getType()->isFloatingPointTy()) {
476     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
477     llvm::Value *Tmp1 = Builder.CreateFMul(LHSr, RHSr, "tmp"); // a*c
478     llvm::Value *Tmp2 = Builder.CreateFMul(LHSi, RHSi, "tmp"); // b*d
479     llvm::Value *Tmp3 = Builder.CreateFAdd(Tmp1, Tmp2, "tmp"); // ac+bd
480 
481     llvm::Value *Tmp4 = Builder.CreateFMul(RHSr, RHSr, "tmp"); // c*c
482     llvm::Value *Tmp5 = Builder.CreateFMul(RHSi, RHSi, "tmp"); // d*d
483     llvm::Value *Tmp6 = Builder.CreateFAdd(Tmp4, Tmp5, "tmp"); // cc+dd
484 
485     llvm::Value *Tmp7 = Builder.CreateFMul(LHSi, RHSr, "tmp"); // b*c
486     llvm::Value *Tmp8 = Builder.CreateFMul(LHSr, RHSi, "tmp"); // a*d
487     llvm::Value *Tmp9 = Builder.CreateFSub(Tmp7, Tmp8, "tmp"); // bc-ad
488 
489     DSTr = Builder.CreateFDiv(Tmp3, Tmp6, "tmp");
490     DSTi = Builder.CreateFDiv(Tmp9, Tmp6, "tmp");
491   } else {
492     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
493     llvm::Value *Tmp1 = Builder.CreateMul(LHSr, RHSr, "tmp"); // a*c
494     llvm::Value *Tmp2 = Builder.CreateMul(LHSi, RHSi, "tmp"); // b*d
495     llvm::Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2, "tmp"); // ac+bd
496 
497     llvm::Value *Tmp4 = Builder.CreateMul(RHSr, RHSr, "tmp"); // c*c
498     llvm::Value *Tmp5 = Builder.CreateMul(RHSi, RHSi, "tmp"); // d*d
499     llvm::Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5, "tmp"); // cc+dd
500 
501     llvm::Value *Tmp7 = Builder.CreateMul(LHSi, RHSr, "tmp"); // b*c
502     llvm::Value *Tmp8 = Builder.CreateMul(LHSr, RHSi, "tmp"); // a*d
503     llvm::Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8, "tmp"); // bc-ad
504 
505     if (Op.Ty->getAs<ComplexType>()->getElementType()->isUnsignedIntegerType()) {
506       DSTr = Builder.CreateUDiv(Tmp3, Tmp6, "tmp");
507       DSTi = Builder.CreateUDiv(Tmp9, Tmp6, "tmp");
508     } else {
509       DSTr = Builder.CreateSDiv(Tmp3, Tmp6, "tmp");
510       DSTi = Builder.CreateSDiv(Tmp9, Tmp6, "tmp");
511     }
512   }
513 
514   return ComplexPairTy(DSTr, DSTi);
515 }
516 
517 ComplexExprEmitter::BinOpInfo
518 ComplexExprEmitter::EmitBinOps(const BinaryOperator *E) {
519   TestAndClearIgnoreReal();
520   TestAndClearIgnoreImag();
521   TestAndClearIgnoreRealAssign();
522   TestAndClearIgnoreImagAssign();
523   BinOpInfo Ops;
524   Ops.LHS = Visit(E->getLHS());
525   Ops.RHS = Visit(E->getRHS());
526   Ops.Ty = E->getType();
527   return Ops;
528 }
529 
530 
531 // Compound assignments.
532 ComplexPairTy ComplexExprEmitter::
533 EmitCompoundAssign(const CompoundAssignOperator *E,
534                    ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&)){
535   TestAndClearIgnoreReal();
536   TestAndClearIgnoreImag();
537   bool ignreal = TestAndClearIgnoreRealAssign();
538   bool ignimag = TestAndClearIgnoreImagAssign();
539   QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType();
540 
541   BinOpInfo OpInfo;
542 
543   // Load the RHS and LHS operands.
544   // __block variables need to have the rhs evaluated first, plus this should
545   // improve codegen a little.  It is possible for the RHS to be complex or
546   // scalar.
547   OpInfo.Ty = E->getComputationResultType();
548   OpInfo.RHS = EmitCast(CK_Unknown, E->getRHS(), OpInfo.Ty);
549 
550   LValue LHS = CGF.EmitLValue(E->getLHS());
551   // We know the LHS is a complex lvalue.
552   ComplexPairTy LHSComplexPair;
553   if (LHS.isPropertyRef())
554     LHSComplexPair =
555       CGF.EmitObjCPropertyGet(LHS.getPropertyRefExpr()).getComplexVal();
556   else if (LHS.isKVCRef())
557     LHSComplexPair =
558       CGF.EmitObjCPropertyGet(LHS.getKVCRefExpr()).getComplexVal();
559   else
560     LHSComplexPair = EmitLoadOfComplex(LHS.getAddress(),
561                                        LHS.isVolatileQualified());
562 
563   OpInfo.LHS = EmitComplexToComplexCast(LHSComplexPair, LHSTy, OpInfo.Ty);
564 
565   // Expand the binary operator.
566   ComplexPairTy Result = (this->*Func)(OpInfo);
567 
568   // Truncate the result back to the LHS type.
569   Result = EmitComplexToComplexCast(Result, OpInfo.Ty, LHSTy);
570 
571   // Store the result value into the LHS lvalue.
572   if (LHS.isPropertyRef())
573     CGF.EmitObjCPropertySet(LHS.getPropertyRefExpr(),
574                             RValue::getComplex(Result));
575   else if (LHS.isKVCRef())
576     CGF.EmitObjCPropertySet(LHS.getKVCRefExpr(), RValue::getComplex(Result));
577   else
578     EmitStoreOfComplex(Result, LHS.getAddress(), LHS.isVolatileQualified());
579 
580   // Restore the Ignore* flags.
581   IgnoreReal = ignreal;
582   IgnoreImag = ignimag;
583   IgnoreRealAssign = ignreal;
584   IgnoreImagAssign = ignimag;
585 
586   // Objective-C property assignment never reloads the value following a store.
587   if (LHS.isPropertyRef() || LHS.isKVCRef())
588     return Result;
589 
590   // Otherwise, reload the value.
591   return EmitLoadOfComplex(LHS.getAddress(), LHS.isVolatileQualified());
592 }
593 
594 ComplexPairTy ComplexExprEmitter::VisitBinAssign(const BinaryOperator *E) {
595   TestAndClearIgnoreReal();
596   TestAndClearIgnoreImag();
597   bool ignreal = TestAndClearIgnoreRealAssign();
598   bool ignimag = TestAndClearIgnoreImagAssign();
599   assert(CGF.getContext().hasSameUnqualifiedType(E->getLHS()->getType(),
600                                                  E->getRHS()->getType()) &&
601          "Invalid assignment");
602   // Emit the RHS.
603   ComplexPairTy Val = Visit(E->getRHS());
604 
605   // Compute the address to store into.
606   LValue LHS = CGF.EmitLValue(E->getLHS());
607 
608   // Store the result value into the LHS lvalue.
609   if (LHS.isPropertyRef())
610     CGF.EmitObjCPropertySet(LHS.getPropertyRefExpr(), RValue::getComplex(Val));
611   else if (LHS.isKVCRef())
612     CGF.EmitObjCPropertySet(LHS.getKVCRefExpr(), RValue::getComplex(Val));
613   else
614     EmitStoreOfComplex(Val, LHS.getAddress(), LHS.isVolatileQualified());
615 
616   // Restore the Ignore* flags.
617   IgnoreReal = ignreal;
618   IgnoreImag = ignimag;
619   IgnoreRealAssign = ignreal;
620   IgnoreImagAssign = ignimag;
621 
622   // Objective-C property assignment never reloads the value following a store.
623   if (LHS.isPropertyRef() || LHS.isKVCRef())
624     return Val;
625 
626   // Otherwise, reload the value.
627   return EmitLoadOfComplex(LHS.getAddress(), LHS.isVolatileQualified());
628 }
629 
630 ComplexPairTy ComplexExprEmitter::VisitBinComma(const BinaryOperator *E) {
631   CGF.EmitStmt(E->getLHS());
632   CGF.EnsureInsertPoint();
633   return Visit(E->getRHS());
634 }
635 
636 ComplexPairTy ComplexExprEmitter::
637 VisitConditionalOperator(const ConditionalOperator *E) {
638 
639   TestAndClearIgnoreReal();
640   TestAndClearIgnoreImag();
641   TestAndClearIgnoreRealAssign();
642   TestAndClearIgnoreImagAssign();
643   llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
644   llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
645   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
646 
647   if (E->getLHS())
648     CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock);
649   else {
650     Expr *save = E->getSAVE();
651     assert(save && "VisitConditionalOperator - save is null");
652     // Intentianlly not doing direct assignment to ConditionalSaveExprs[save] !!
653     ComplexPairTy SaveVal = Visit(save);
654     CGF.ConditionalSaveComplexExprs[save] = SaveVal;
655     CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock);
656   }
657 
658   CGF.EmitBlock(LHSBlock);
659   ComplexPairTy LHS = Visit(E->getTrueExpr());
660   LHSBlock = Builder.GetInsertBlock();
661   CGF.EmitBranch(ContBlock);
662 
663   CGF.EmitBlock(RHSBlock);
664 
665   ComplexPairTy RHS = Visit(E->getRHS());
666   RHSBlock = Builder.GetInsertBlock();
667   CGF.EmitBranch(ContBlock);
668 
669   CGF.EmitBlock(ContBlock);
670 
671   // Create a PHI node for the real part.
672   llvm::PHINode *RealPN = Builder.CreatePHI(LHS.first->getType(), "cond.r");
673   RealPN->reserveOperandSpace(2);
674   RealPN->addIncoming(LHS.first, LHSBlock);
675   RealPN->addIncoming(RHS.first, RHSBlock);
676 
677   // Create a PHI node for the imaginary part.
678   llvm::PHINode *ImagPN = Builder.CreatePHI(LHS.first->getType(), "cond.i");
679   ImagPN->reserveOperandSpace(2);
680   ImagPN->addIncoming(LHS.second, LHSBlock);
681   ImagPN->addIncoming(RHS.second, RHSBlock);
682 
683   return ComplexPairTy(RealPN, ImagPN);
684 }
685 
686 ComplexPairTy ComplexExprEmitter::VisitChooseExpr(ChooseExpr *E) {
687   return Visit(E->getChosenSubExpr(CGF.getContext()));
688 }
689 
690 ComplexPairTy ComplexExprEmitter::VisitInitListExpr(InitListExpr *E) {
691     bool Ignore = TestAndClearIgnoreReal();
692     (void)Ignore;
693     assert (Ignore == false && "init list ignored");
694     Ignore = TestAndClearIgnoreImag();
695     (void)Ignore;
696     assert (Ignore == false && "init list ignored");
697   if (E->getNumInits())
698     return Visit(E->getInit(0));
699 
700   // Empty init list intializes to null
701   QualType Ty = E->getType()->getAs<ComplexType>()->getElementType();
702   const llvm::Type* LTy = CGF.ConvertType(Ty);
703   llvm::Value* zeroConstant = llvm::Constant::getNullValue(LTy);
704   return ComplexPairTy(zeroConstant, zeroConstant);
705 }
706 
707 ComplexPairTy ComplexExprEmitter::VisitVAArgExpr(VAArgExpr *E) {
708   llvm::Value *ArgValue = CGF.EmitVAListRef(E->getSubExpr());
709   llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, E->getType());
710 
711   if (!ArgPtr) {
712     CGF.ErrorUnsupported(E, "complex va_arg expression");
713     const llvm::Type *EltTy =
714       CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
715     llvm::Value *U = llvm::UndefValue::get(EltTy);
716     return ComplexPairTy(U, U);
717   }
718 
719   // FIXME Volatility.
720   return EmitLoadOfComplex(ArgPtr, false);
721 }
722 
723 //===----------------------------------------------------------------------===//
724 //                         Entry Point into this File
725 //===----------------------------------------------------------------------===//
726 
727 /// EmitComplexExpr - Emit the computation of the specified expression of
728 /// complex type, ignoring the result.
729 ComplexPairTy CodeGenFunction::EmitComplexExpr(const Expr *E, bool IgnoreReal,
730                                                bool IgnoreImag, bool IgnoreRealAssign, bool IgnoreImagAssign) {
731   assert(E && E->getType()->isAnyComplexType() &&
732          "Invalid complex expression to emit");
733 
734   return ComplexExprEmitter(*this, IgnoreReal, IgnoreImag, IgnoreRealAssign,
735                             IgnoreImagAssign)
736     .Visit(const_cast<Expr*>(E));
737 }
738 
739 /// EmitComplexExprIntoAddr - Emit the computation of the specified expression
740 /// of complex type, storing into the specified Value*.
741 void CodeGenFunction::EmitComplexExprIntoAddr(const Expr *E,
742                                               llvm::Value *DestAddr,
743                                               bool DestIsVolatile) {
744   assert(E && E->getType()->isAnyComplexType() &&
745          "Invalid complex expression to emit");
746   ComplexExprEmitter Emitter(*this);
747   ComplexPairTy Val = Emitter.Visit(const_cast<Expr*>(E));
748   Emitter.EmitStoreOfComplex(Val, DestAddr, DestIsVolatile);
749 }
750 
751 /// StoreComplexToAddr - Store a complex number into the specified address.
752 void CodeGenFunction::StoreComplexToAddr(ComplexPairTy V,
753                                          llvm::Value *DestAddr,
754                                          bool DestIsVolatile) {
755   ComplexExprEmitter(*this).EmitStoreOfComplex(V, DestAddr, DestIsVolatile);
756 }
757 
758 /// LoadComplexFromAddr - Load a complex number from the specified address.
759 ComplexPairTy CodeGenFunction::LoadComplexFromAddr(llvm::Value *SrcAddr,
760                                                    bool SrcIsVolatile) {
761   return ComplexExprEmitter(*this).EmitLoadOfComplex(SrcAddr, SrcIsVolatile);
762 }
763