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 VisitStmt(Stmt *S) {
106     S->dump(CGF.getContext().getSourceManager());
107     assert(0 && "Stmt can't have complex result type!");
108     return ComplexPairTy();
109   }
110   ComplexPairTy VisitExpr(Expr *S);
111   ComplexPairTy VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr());}
112   ComplexPairTy VisitImaginaryLiteral(const ImaginaryLiteral *IL);
113 
114   // l-values.
115   ComplexPairTy VisitDeclRefExpr(const Expr *E) { return EmitLoadOfLValue(E); }
116   ComplexPairTy VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
117     return EmitLoadOfLValue(E);
118   }
119   ComplexPairTy VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) {
120     return EmitLoadOfLValue(E);
121   }
122   ComplexPairTy VisitObjCImplicitSetterGetterRefExpr(
123                                ObjCImplicitSetterGetterRefExpr *E) {
124     return EmitLoadOfLValue(E);
125   }
126   ComplexPairTy VisitObjCMessageExpr(ObjCMessageExpr *E) {
127     return CGF.EmitObjCMessageExpr(E).getComplexVal();
128   }
129   ComplexPairTy VisitArraySubscriptExpr(Expr *E) { return EmitLoadOfLValue(E); }
130   ComplexPairTy VisitMemberExpr(const Expr *E) { return EmitLoadOfLValue(E); }
131 
132   // FIXME: CompoundLiteralExpr
133 
134   ComplexPairTy EmitCast(CastExpr::CastKind CK, Expr *Op, QualType DestTy);
135   ComplexPairTy VisitImplicitCastExpr(ImplicitCastExpr *E) {
136     // Unlike for scalars, we don't have to worry about function->ptr demotion
137     // here.
138     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
139   }
140   ComplexPairTy VisitCastExpr(CastExpr *E) {
141     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
142   }
143   ComplexPairTy VisitCallExpr(const CallExpr *E);
144   ComplexPairTy VisitStmtExpr(const StmtExpr *E);
145 
146   // Operators.
147   ComplexPairTy VisitPrePostIncDec(const UnaryOperator *E,
148                                    bool isInc, bool isPre) {
149     LValue LV = CGF.EmitLValue(E->getSubExpr());
150     return CGF.EmitComplexPrePostIncDec(E, LV, isInc, isPre);
151   }
152   ComplexPairTy VisitUnaryPostDec(const UnaryOperator *E) {
153     return VisitPrePostIncDec(E, false, false);
154   }
155   ComplexPairTy VisitUnaryPostInc(const UnaryOperator *E) {
156     return VisitPrePostIncDec(E, true, false);
157   }
158   ComplexPairTy VisitUnaryPreDec(const UnaryOperator *E) {
159     return VisitPrePostIncDec(E, false, true);
160   }
161   ComplexPairTy VisitUnaryPreInc(const UnaryOperator *E) {
162     return VisitPrePostIncDec(E, true, true);
163   }
164   ComplexPairTy VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); }
165   ComplexPairTy VisitUnaryPlus     (const UnaryOperator *E) {
166     TestAndClearIgnoreReal();
167     TestAndClearIgnoreImag();
168     TestAndClearIgnoreRealAssign();
169     TestAndClearIgnoreImagAssign();
170     return Visit(E->getSubExpr());
171   }
172   ComplexPairTy VisitUnaryMinus    (const UnaryOperator *E);
173   ComplexPairTy VisitUnaryNot      (const UnaryOperator *E);
174   // LNot,Real,Imag never return complex.
175   ComplexPairTy VisitUnaryExtension(const UnaryOperator *E) {
176     return Visit(E->getSubExpr());
177   }
178   ComplexPairTy VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
179     return Visit(DAE->getExpr());
180   }
181   ComplexPairTy VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) {
182     return CGF.EmitCXXExprWithTemporaries(E).getComplexVal();
183   }
184   ComplexPairTy VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E) {
185     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
186     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
187     llvm::Constant *Null = llvm::Constant::getNullValue(CGF.ConvertType(Elem));
188     return ComplexPairTy(Null, Null);
189   }
190   ComplexPairTy VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
191     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
192     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
193     llvm::Constant *Null =
194                        llvm::Constant::getNullValue(CGF.ConvertType(Elem));
195     return ComplexPairTy(Null, Null);
196   }
197 
198   struct BinOpInfo {
199     ComplexPairTy LHS;
200     ComplexPairTy RHS;
201     QualType Ty;  // Computation Type.
202   };
203 
204   BinOpInfo EmitBinOps(const BinaryOperator *E);
205   ComplexPairTy EmitCompoundAssign(const CompoundAssignOperator *E,
206                                    ComplexPairTy (ComplexExprEmitter::*Func)
207                                    (const BinOpInfo &));
208 
209   ComplexPairTy EmitBinAdd(const BinOpInfo &Op);
210   ComplexPairTy EmitBinSub(const BinOpInfo &Op);
211   ComplexPairTy EmitBinMul(const BinOpInfo &Op);
212   ComplexPairTy EmitBinDiv(const BinOpInfo &Op);
213 
214   ComplexPairTy VisitBinMul(const BinaryOperator *E) {
215     return EmitBinMul(EmitBinOps(E));
216   }
217   ComplexPairTy VisitBinAdd(const BinaryOperator *E) {
218     return EmitBinAdd(EmitBinOps(E));
219   }
220   ComplexPairTy VisitBinSub(const BinaryOperator *E) {
221     return EmitBinSub(EmitBinOps(E));
222   }
223   ComplexPairTy VisitBinDiv(const BinaryOperator *E) {
224     return EmitBinDiv(EmitBinOps(E));
225   }
226 
227   // Compound assignments.
228   ComplexPairTy VisitBinAddAssign(const CompoundAssignOperator *E) {
229     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinAdd);
230   }
231   ComplexPairTy VisitBinSubAssign(const CompoundAssignOperator *E) {
232     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinSub);
233   }
234   ComplexPairTy VisitBinMulAssign(const CompoundAssignOperator *E) {
235     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinMul);
236   }
237   ComplexPairTy VisitBinDivAssign(const CompoundAssignOperator *E) {
238     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinDiv);
239   }
240 
241   // GCC rejects rem/and/or/xor for integer complex.
242   // Logical and/or always return int, never complex.
243 
244   // No comparisons produce a complex result.
245   ComplexPairTy VisitBinAssign     (const BinaryOperator *E);
246   ComplexPairTy VisitBinComma      (const BinaryOperator *E);
247 
248 
249   ComplexPairTy VisitConditionalOperator(const ConditionalOperator *CO);
250   ComplexPairTy VisitChooseExpr(ChooseExpr *CE);
251 
252   ComplexPairTy VisitInitListExpr(InitListExpr *E);
253 
254   ComplexPairTy VisitVAArgExpr(VAArgExpr *E);
255 };
256 }  // end anonymous namespace.
257 
258 //===----------------------------------------------------------------------===//
259 //                                Utilities
260 //===----------------------------------------------------------------------===//
261 
262 /// EmitLoadOfComplex - Given an RValue reference for a complex, emit code to
263 /// load the real and imaginary pieces, returning them as Real/Imag.
264 ComplexPairTy ComplexExprEmitter::EmitLoadOfComplex(llvm::Value *SrcPtr,
265                                                     bool isVolatile) {
266   llvm::Value *Real=0, *Imag=0;
267 
268   if (!IgnoreReal) {
269     llvm::Value *RealP = Builder.CreateStructGEP(SrcPtr, 0,
270                                                  SrcPtr->getName() + ".realp");
271     Real = Builder.CreateLoad(RealP, isVolatile, SrcPtr->getName() + ".real");
272   }
273 
274   if (!IgnoreImag) {
275     llvm::Value *ImagP = Builder.CreateStructGEP(SrcPtr, 1,
276                                                  SrcPtr->getName() + ".imagp");
277     Imag = Builder.CreateLoad(ImagP, isVolatile, SrcPtr->getName() + ".imag");
278   }
279   return ComplexPairTy(Real, Imag);
280 }
281 
282 /// EmitStoreOfComplex - Store the specified real/imag parts into the
283 /// specified value pointer.
284 void ComplexExprEmitter::EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *Ptr,
285                                             bool isVolatile) {
286   llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, "real");
287   llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, "imag");
288 
289   Builder.CreateStore(Val.first, RealPtr, isVolatile);
290   Builder.CreateStore(Val.second, ImagPtr, isVolatile);
291 }
292 
293 
294 
295 //===----------------------------------------------------------------------===//
296 //                            Visitor Methods
297 //===----------------------------------------------------------------------===//
298 
299 ComplexPairTy ComplexExprEmitter::VisitExpr(Expr *E) {
300   CGF.ErrorUnsupported(E, "complex expression");
301   const llvm::Type *EltTy =
302     CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
303   llvm::Value *U = llvm::UndefValue::get(EltTy);
304   return ComplexPairTy(U, U);
305 }
306 
307 ComplexPairTy ComplexExprEmitter::
308 VisitImaginaryLiteral(const ImaginaryLiteral *IL) {
309   llvm::Value *Imag = CGF.EmitScalarExpr(IL->getSubExpr());
310   return
311         ComplexPairTy(llvm::Constant::getNullValue(Imag->getType()), Imag);
312 }
313 
314 
315 ComplexPairTy ComplexExprEmitter::VisitCallExpr(const CallExpr *E) {
316   if (E->getCallReturnType()->isReferenceType())
317     return EmitLoadOfLValue(E);
318 
319   return CGF.EmitCallExpr(E).getComplexVal();
320 }
321 
322 ComplexPairTy ComplexExprEmitter::VisitStmtExpr(const StmtExpr *E) {
323   return CGF.EmitCompoundStmt(*E->getSubStmt(), true).getComplexVal();
324 }
325 
326 /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
327 ComplexPairTy ComplexExprEmitter::EmitComplexToComplexCast(ComplexPairTy Val,
328                                                            QualType SrcType,
329                                                            QualType DestType) {
330   // Get the src/dest element type.
331   SrcType = SrcType->getAs<ComplexType>()->getElementType();
332   DestType = DestType->getAs<ComplexType>()->getElementType();
333 
334   // C99 6.3.1.6: When a value of complex type is converted to another
335   // complex type, both the real and imaginary parts follow the conversion
336   // rules for the corresponding real types.
337   Val.first = CGF.EmitScalarConversion(Val.first, SrcType, DestType);
338   Val.second = CGF.EmitScalarConversion(Val.second, SrcType, DestType);
339   return Val;
340 }
341 
342 ComplexPairTy ComplexExprEmitter::EmitCast(CastExpr::CastKind CK, Expr *Op,
343                                            QualType DestTy) {
344   // Two cases here: cast from (complex to complex) and (scalar to complex).
345   if (Op->getType()->isAnyComplexType())
346     return EmitComplexToComplexCast(Visit(Op), Op->getType(), DestTy);
347 
348   // FIXME: We should be looking at all of the cast kinds here, not
349   // cherry-picking the ones we have test cases for.
350   if (CK == CastExpr::CK_LValueBitCast) {
351     llvm::Value *V = CGF.EmitLValue(Op).getAddress();
352     V = Builder.CreateBitCast(V,
353                       CGF.ConvertType(CGF.getContext().getPointerType(DestTy)));
354     // FIXME: Are the qualifiers correct here?
355     return EmitLoadOfComplex(V, DestTy.isVolatileQualified());
356   }
357 
358   // C99 6.3.1.7: When a value of real type is converted to a complex type, the
359   // real part of the complex result value is determined by the rules of
360   // conversion to the corresponding real type and the imaginary part of the
361   // complex result value is a positive zero or an unsigned zero.
362   llvm::Value *Elt = CGF.EmitScalarExpr(Op);
363 
364   // Convert the input element to the element type of the complex.
365   DestTy = DestTy->getAs<ComplexType>()->getElementType();
366   Elt = CGF.EmitScalarConversion(Elt, Op->getType(), DestTy);
367 
368   // Return (realval, 0).
369   return ComplexPairTy(Elt, llvm::Constant::getNullValue(Elt->getType()));
370 }
371 
372 ComplexPairTy ComplexExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
373   TestAndClearIgnoreReal();
374   TestAndClearIgnoreImag();
375   TestAndClearIgnoreRealAssign();
376   TestAndClearIgnoreImagAssign();
377   ComplexPairTy Op = Visit(E->getSubExpr());
378 
379   llvm::Value *ResR, *ResI;
380   if (Op.first->getType()->isFloatingPointTy()) {
381     ResR = Builder.CreateFNeg(Op.first,  "neg.r");
382     ResI = Builder.CreateFNeg(Op.second, "neg.i");
383   } else {
384     ResR = Builder.CreateNeg(Op.first,  "neg.r");
385     ResI = Builder.CreateNeg(Op.second, "neg.i");
386   }
387   return ComplexPairTy(ResR, ResI);
388 }
389 
390 ComplexPairTy ComplexExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
391   TestAndClearIgnoreReal();
392   TestAndClearIgnoreImag();
393   TestAndClearIgnoreRealAssign();
394   TestAndClearIgnoreImagAssign();
395   // ~(a+ib) = a + i*-b
396   ComplexPairTy Op = Visit(E->getSubExpr());
397   llvm::Value *ResI;
398   if (Op.second->getType()->isFloatingPointTy())
399     ResI = Builder.CreateFNeg(Op.second, "conj.i");
400   else
401     ResI = Builder.CreateNeg(Op.second, "conj.i");
402 
403   return ComplexPairTy(Op.first, ResI);
404 }
405 
406 ComplexPairTy ComplexExprEmitter::EmitBinAdd(const BinOpInfo &Op) {
407   llvm::Value *ResR, *ResI;
408 
409   if (Op.LHS.first->getType()->isFloatingPointTy()) {
410     ResR = Builder.CreateFAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
411     ResI = Builder.CreateFAdd(Op.LHS.second, Op.RHS.second, "add.i");
412   } else {
413     ResR = Builder.CreateAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
414     ResI = Builder.CreateAdd(Op.LHS.second, Op.RHS.second, "add.i");
415   }
416   return ComplexPairTy(ResR, ResI);
417 }
418 
419 ComplexPairTy ComplexExprEmitter::EmitBinSub(const BinOpInfo &Op) {
420   llvm::Value *ResR, *ResI;
421   if (Op.LHS.first->getType()->isFloatingPointTy()) {
422     ResR = Builder.CreateFSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
423     ResI = Builder.CreateFSub(Op.LHS.second, Op.RHS.second, "sub.i");
424   } else {
425     ResR = Builder.CreateSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
426     ResI = Builder.CreateSub(Op.LHS.second, Op.RHS.second, "sub.i");
427   }
428   return ComplexPairTy(ResR, ResI);
429 }
430 
431 
432 ComplexPairTy ComplexExprEmitter::EmitBinMul(const BinOpInfo &Op) {
433   using llvm::Value;
434   Value *ResR, *ResI;
435 
436   if (Op.LHS.first->getType()->isFloatingPointTy()) {
437     Value *ResRl = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul.rl");
438     Value *ResRr = Builder.CreateFMul(Op.LHS.second, Op.RHS.second,"mul.rr");
439     ResR  = Builder.CreateFSub(ResRl, ResRr, "mul.r");
440 
441     Value *ResIl = Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul.il");
442     Value *ResIr = Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul.ir");
443     ResI  = Builder.CreateFAdd(ResIl, ResIr, "mul.i");
444   } else {
445     Value *ResRl = Builder.CreateMul(Op.LHS.first, Op.RHS.first, "mul.rl");
446     Value *ResRr = Builder.CreateMul(Op.LHS.second, Op.RHS.second,"mul.rr");
447     ResR  = Builder.CreateSub(ResRl, ResRr, "mul.r");
448 
449     Value *ResIl = Builder.CreateMul(Op.LHS.second, Op.RHS.first, "mul.il");
450     Value *ResIr = Builder.CreateMul(Op.LHS.first, Op.RHS.second, "mul.ir");
451     ResI  = Builder.CreateAdd(ResIl, ResIr, "mul.i");
452   }
453   return ComplexPairTy(ResR, ResI);
454 }
455 
456 ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
457   llvm::Value *LHSr = Op.LHS.first, *LHSi = Op.LHS.second;
458   llvm::Value *RHSr = Op.RHS.first, *RHSi = Op.RHS.second;
459 
460 
461   llvm::Value *DSTr, *DSTi;
462   if (Op.LHS.first->getType()->isFloatingPointTy()) {
463     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
464     llvm::Value *Tmp1 = Builder.CreateFMul(LHSr, RHSr, "tmp"); // a*c
465     llvm::Value *Tmp2 = Builder.CreateFMul(LHSi, RHSi, "tmp"); // b*d
466     llvm::Value *Tmp3 = Builder.CreateFAdd(Tmp1, Tmp2, "tmp"); // ac+bd
467 
468     llvm::Value *Tmp4 = Builder.CreateFMul(RHSr, RHSr, "tmp"); // c*c
469     llvm::Value *Tmp5 = Builder.CreateFMul(RHSi, RHSi, "tmp"); // d*d
470     llvm::Value *Tmp6 = Builder.CreateFAdd(Tmp4, Tmp5, "tmp"); // cc+dd
471 
472     llvm::Value *Tmp7 = Builder.CreateFMul(LHSi, RHSr, "tmp"); // b*c
473     llvm::Value *Tmp8 = Builder.CreateFMul(LHSr, RHSi, "tmp"); // a*d
474     llvm::Value *Tmp9 = Builder.CreateFSub(Tmp7, Tmp8, "tmp"); // bc-ad
475 
476     DSTr = Builder.CreateFDiv(Tmp3, Tmp6, "tmp");
477     DSTi = Builder.CreateFDiv(Tmp9, Tmp6, "tmp");
478   } else {
479     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
480     llvm::Value *Tmp1 = Builder.CreateMul(LHSr, RHSr, "tmp"); // a*c
481     llvm::Value *Tmp2 = Builder.CreateMul(LHSi, RHSi, "tmp"); // b*d
482     llvm::Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2, "tmp"); // ac+bd
483 
484     llvm::Value *Tmp4 = Builder.CreateMul(RHSr, RHSr, "tmp"); // c*c
485     llvm::Value *Tmp5 = Builder.CreateMul(RHSi, RHSi, "tmp"); // d*d
486     llvm::Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5, "tmp"); // cc+dd
487 
488     llvm::Value *Tmp7 = Builder.CreateMul(LHSi, RHSr, "tmp"); // b*c
489     llvm::Value *Tmp8 = Builder.CreateMul(LHSr, RHSi, "tmp"); // a*d
490     llvm::Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8, "tmp"); // bc-ad
491 
492     if (Op.Ty->getAs<ComplexType>()->getElementType()->isUnsignedIntegerType()) {
493       DSTr = Builder.CreateUDiv(Tmp3, Tmp6, "tmp");
494       DSTi = Builder.CreateUDiv(Tmp9, Tmp6, "tmp");
495     } else {
496       DSTr = Builder.CreateSDiv(Tmp3, Tmp6, "tmp");
497       DSTi = Builder.CreateSDiv(Tmp9, Tmp6, "tmp");
498     }
499   }
500 
501   return ComplexPairTy(DSTr, DSTi);
502 }
503 
504 ComplexExprEmitter::BinOpInfo
505 ComplexExprEmitter::EmitBinOps(const BinaryOperator *E) {
506   TestAndClearIgnoreReal();
507   TestAndClearIgnoreImag();
508   TestAndClearIgnoreRealAssign();
509   TestAndClearIgnoreImagAssign();
510   BinOpInfo Ops;
511   Ops.LHS = Visit(E->getLHS());
512   Ops.RHS = Visit(E->getRHS());
513   Ops.Ty = E->getType();
514   return Ops;
515 }
516 
517 
518 // Compound assignments.
519 ComplexPairTy ComplexExprEmitter::
520 EmitCompoundAssign(const CompoundAssignOperator *E,
521                    ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&)){
522   TestAndClearIgnoreReal();
523   TestAndClearIgnoreImag();
524   bool ignreal = TestAndClearIgnoreRealAssign();
525   bool ignimag = TestAndClearIgnoreImagAssign();
526   QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType();
527 
528   BinOpInfo OpInfo;
529 
530   // Load the RHS and LHS operands.
531   // __block variables need to have the rhs evaluated first, plus this should
532   // improve codegen a little.  It is possible for the RHS to be complex or
533   // scalar.
534   OpInfo.Ty = E->getComputationResultType();
535   OpInfo.RHS = EmitCast(CastExpr::CK_Unknown, E->getRHS(), OpInfo.Ty);
536 
537   LValue LHS = CGF.EmitLValue(E->getLHS());
538   // We know the LHS is a complex lvalue.
539   ComplexPairTy LHSComplexPair;
540   if (LHS.isPropertyRef())
541     LHSComplexPair =
542       CGF.EmitObjCPropertyGet(LHS.getPropertyRefExpr()).getComplexVal();
543   else if (LHS.isKVCRef())
544     LHSComplexPair =
545       CGF.EmitObjCPropertyGet(LHS.getKVCRefExpr()).getComplexVal();
546   else
547     LHSComplexPair = EmitLoadOfComplex(LHS.getAddress(),
548                                        LHS.isVolatileQualified());
549 
550   OpInfo.LHS = EmitComplexToComplexCast(LHSComplexPair, LHSTy, OpInfo.Ty);
551 
552   // Expand the binary operator.
553   ComplexPairTy Result = (this->*Func)(OpInfo);
554 
555   // Truncate the result back to the LHS type.
556   Result = EmitComplexToComplexCast(Result, OpInfo.Ty, LHSTy);
557 
558   // Store the result value into the LHS lvalue.
559   if (LHS.isPropertyRef())
560     CGF.EmitObjCPropertySet(LHS.getPropertyRefExpr(),
561                             RValue::getComplex(Result));
562   else if (LHS.isKVCRef())
563     CGF.EmitObjCPropertySet(LHS.getKVCRefExpr(), RValue::getComplex(Result));
564   else
565     EmitStoreOfComplex(Result, LHS.getAddress(), LHS.isVolatileQualified());
566 
567   // Restore the Ignore* flags.
568   IgnoreReal = ignreal;
569   IgnoreImag = ignimag;
570   IgnoreRealAssign = ignreal;
571   IgnoreImagAssign = ignimag;
572 
573   // Objective-C property assignment never reloads the value following a store.
574   if (LHS.isPropertyRef() || LHS.isKVCRef())
575     return Result;
576 
577   // Otherwise, reload the value.
578   return EmitLoadOfComplex(LHS.getAddress(), LHS.isVolatileQualified());
579 }
580 
581 ComplexPairTy ComplexExprEmitter::VisitBinAssign(const BinaryOperator *E) {
582   TestAndClearIgnoreReal();
583   TestAndClearIgnoreImag();
584   bool ignreal = TestAndClearIgnoreRealAssign();
585   bool ignimag = TestAndClearIgnoreImagAssign();
586   assert(CGF.getContext().hasSameUnqualifiedType(E->getLHS()->getType(),
587                                                  E->getRHS()->getType()) &&
588          "Invalid assignment");
589   // Emit the RHS.
590   ComplexPairTy Val = Visit(E->getRHS());
591 
592   // Compute the address to store into.
593   LValue LHS = CGF.EmitLValue(E->getLHS());
594 
595   // Store the result value into the LHS lvalue.
596   if (LHS.isPropertyRef())
597     CGF.EmitObjCPropertySet(LHS.getPropertyRefExpr(), RValue::getComplex(Val));
598   else if (LHS.isKVCRef())
599     CGF.EmitObjCPropertySet(LHS.getKVCRefExpr(), RValue::getComplex(Val));
600   else
601     EmitStoreOfComplex(Val, LHS.getAddress(), LHS.isVolatileQualified());
602 
603   // Restore the Ignore* flags.
604   IgnoreReal = ignreal;
605   IgnoreImag = ignimag;
606   IgnoreRealAssign = ignreal;
607   IgnoreImagAssign = ignimag;
608 
609   // Objective-C property assignment never reloads the value following a store.
610   if (LHS.isPropertyRef() || LHS.isKVCRef())
611     return Val;
612 
613   // Otherwise, reload the value.
614   return EmitLoadOfComplex(LHS.getAddress(), LHS.isVolatileQualified());
615 }
616 
617 ComplexPairTy ComplexExprEmitter::VisitBinComma(const BinaryOperator *E) {
618   CGF.EmitStmt(E->getLHS());
619   CGF.EnsureInsertPoint();
620   return Visit(E->getRHS());
621 }
622 
623 ComplexPairTy ComplexExprEmitter::
624 VisitConditionalOperator(const ConditionalOperator *E) {
625   if (!E->getLHS()) {
626     CGF.ErrorUnsupported(E, "conditional operator with missing LHS");
627     const llvm::Type *EltTy =
628       CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
629     llvm::Value *U = llvm::UndefValue::get(EltTy);
630     return ComplexPairTy(U, U);
631   }
632 
633   TestAndClearIgnoreReal();
634   TestAndClearIgnoreImag();
635   TestAndClearIgnoreRealAssign();
636   TestAndClearIgnoreImagAssign();
637   llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
638   llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
639   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
640 
641   CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock);
642 
643   CGF.EmitBlock(LHSBlock);
644 
645   // Handle the GNU extension for missing LHS.
646   assert(E->getLHS() && "Must have LHS for complex value");
647 
648   ComplexPairTy LHS = Visit(E->getLHS());
649   LHSBlock = Builder.GetInsertBlock();
650   CGF.EmitBranch(ContBlock);
651 
652   CGF.EmitBlock(RHSBlock);
653 
654   ComplexPairTy RHS = Visit(E->getRHS());
655   RHSBlock = Builder.GetInsertBlock();
656   CGF.EmitBranch(ContBlock);
657 
658   CGF.EmitBlock(ContBlock);
659 
660   // Create a PHI node for the real part.
661   llvm::PHINode *RealPN = Builder.CreatePHI(LHS.first->getType(), "cond.r");
662   RealPN->reserveOperandSpace(2);
663   RealPN->addIncoming(LHS.first, LHSBlock);
664   RealPN->addIncoming(RHS.first, RHSBlock);
665 
666   // Create a PHI node for the imaginary part.
667   llvm::PHINode *ImagPN = Builder.CreatePHI(LHS.first->getType(), "cond.i");
668   ImagPN->reserveOperandSpace(2);
669   ImagPN->addIncoming(LHS.second, LHSBlock);
670   ImagPN->addIncoming(RHS.second, RHSBlock);
671 
672   return ComplexPairTy(RealPN, ImagPN);
673 }
674 
675 ComplexPairTy ComplexExprEmitter::VisitChooseExpr(ChooseExpr *E) {
676   return Visit(E->getChosenSubExpr(CGF.getContext()));
677 }
678 
679 ComplexPairTy ComplexExprEmitter::VisitInitListExpr(InitListExpr *E) {
680     bool Ignore = TestAndClearIgnoreReal();
681     (void)Ignore;
682     assert (Ignore == false && "init list ignored");
683     Ignore = TestAndClearIgnoreImag();
684     (void)Ignore;
685     assert (Ignore == false && "init list ignored");
686   if (E->getNumInits())
687     return Visit(E->getInit(0));
688 
689   // Empty init list intializes to null
690   QualType Ty = E->getType()->getAs<ComplexType>()->getElementType();
691   const llvm::Type* LTy = CGF.ConvertType(Ty);
692   llvm::Value* zeroConstant = llvm::Constant::getNullValue(LTy);
693   return ComplexPairTy(zeroConstant, zeroConstant);
694 }
695 
696 ComplexPairTy ComplexExprEmitter::VisitVAArgExpr(VAArgExpr *E) {
697   llvm::Value *ArgValue = CGF.EmitVAListRef(E->getSubExpr());
698   llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, E->getType());
699 
700   if (!ArgPtr) {
701     CGF.ErrorUnsupported(E, "complex va_arg expression");
702     const llvm::Type *EltTy =
703       CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
704     llvm::Value *U = llvm::UndefValue::get(EltTy);
705     return ComplexPairTy(U, U);
706   }
707 
708   // FIXME Volatility.
709   return EmitLoadOfComplex(ArgPtr, false);
710 }
711 
712 //===----------------------------------------------------------------------===//
713 //                         Entry Point into this File
714 //===----------------------------------------------------------------------===//
715 
716 /// EmitComplexExpr - Emit the computation of the specified expression of
717 /// complex type, ignoring the result.
718 ComplexPairTy CodeGenFunction::EmitComplexExpr(const Expr *E, bool IgnoreReal,
719                                                bool IgnoreImag, bool IgnoreRealAssign, bool IgnoreImagAssign) {
720   assert(E && E->getType()->isAnyComplexType() &&
721          "Invalid complex expression to emit");
722 
723   return ComplexExprEmitter(*this, IgnoreReal, IgnoreImag, IgnoreRealAssign,
724                             IgnoreImagAssign)
725     .Visit(const_cast<Expr*>(E));
726 }
727 
728 /// EmitComplexExprIntoAddr - Emit the computation of the specified expression
729 /// of complex type, storing into the specified Value*.
730 void CodeGenFunction::EmitComplexExprIntoAddr(const Expr *E,
731                                               llvm::Value *DestAddr,
732                                               bool DestIsVolatile) {
733   assert(E && E->getType()->isAnyComplexType() &&
734          "Invalid complex expression to emit");
735   ComplexExprEmitter Emitter(*this);
736   ComplexPairTy Val = Emitter.Visit(const_cast<Expr*>(E));
737   Emitter.EmitStoreOfComplex(Val, DestAddr, DestIsVolatile);
738 }
739 
740 /// StoreComplexToAddr - Store a complex number into the specified address.
741 void CodeGenFunction::StoreComplexToAddr(ComplexPairTy V,
742                                          llvm::Value *DestAddr,
743                                          bool DestIsVolatile) {
744   ComplexExprEmitter(*this).EmitStoreOfComplex(V, DestAddr, DestIsVolatile);
745 }
746 
747 /// LoadComplexFromAddr - Load a complex number from the specified address.
748 ComplexPairTy CodeGenFunction::LoadComplexFromAddr(llvm::Value *SrcAddr,
749                                                    bool SrcIsVolatile) {
750   return ComplexExprEmitter(*this).EmitLoadOfComplex(SrcAddr, SrcIsVolatile);
751 }
752