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(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->getSubExpr(), E->getType());
139   }
140   ComplexPairTy VisitCastExpr(CastExpr *E) {
141     return EmitCast(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   ComplexPairTy VisitUnaryPostDec(const UnaryOperator *E) {
150     return VisitPrePostIncDec(E, false, false);
151   }
152   ComplexPairTy VisitUnaryPostInc(const UnaryOperator *E) {
153     return VisitPrePostIncDec(E, true, false);
154   }
155   ComplexPairTy VisitUnaryPreDec(const UnaryOperator *E) {
156     return VisitPrePostIncDec(E, false, true);
157   }
158   ComplexPairTy VisitUnaryPreInc(const UnaryOperator *E) {
159     return VisitPrePostIncDec(E, true, true);
160   }
161   ComplexPairTy VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); }
162   ComplexPairTy VisitUnaryPlus     (const UnaryOperator *E) {
163     TestAndClearIgnoreReal();
164     TestAndClearIgnoreImag();
165     TestAndClearIgnoreRealAssign();
166     TestAndClearIgnoreImagAssign();
167     return Visit(E->getSubExpr());
168   }
169   ComplexPairTy VisitUnaryMinus    (const UnaryOperator *E);
170   ComplexPairTy VisitUnaryNot      (const UnaryOperator *E);
171   // LNot,Real,Imag never return complex.
172   ComplexPairTy VisitUnaryExtension(const UnaryOperator *E) {
173     return Visit(E->getSubExpr());
174   }
175   ComplexPairTy VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
176     return Visit(DAE->getExpr());
177   }
178   ComplexPairTy VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) {
179     return CGF.EmitCXXExprWithTemporaries(E).getComplexVal();
180   }
181   ComplexPairTy VisitCXXZeroInitValueExpr(CXXZeroInitValueExpr *E) {
182     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
183     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
184     llvm::Constant *Null = llvm::Constant::getNullValue(CGF.ConvertType(Elem));
185     return ComplexPairTy(Null, Null);
186   }
187   ComplexPairTy VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
188     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
189     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
190     llvm::Constant *Null =
191                        llvm::Constant::getNullValue(CGF.ConvertType(Elem));
192     return ComplexPairTy(Null, Null);
193   }
194 
195   struct BinOpInfo {
196     ComplexPairTy LHS;
197     ComplexPairTy RHS;
198     QualType Ty;  // Computation Type.
199   };
200 
201   BinOpInfo EmitBinOps(const BinaryOperator *E);
202   ComplexPairTy EmitCompoundAssign(const CompoundAssignOperator *E,
203                                    ComplexPairTy (ComplexExprEmitter::*Func)
204                                    (const BinOpInfo &));
205 
206   ComplexPairTy EmitBinAdd(const BinOpInfo &Op);
207   ComplexPairTy EmitBinSub(const BinOpInfo &Op);
208   ComplexPairTy EmitBinMul(const BinOpInfo &Op);
209   ComplexPairTy EmitBinDiv(const BinOpInfo &Op);
210 
211   ComplexPairTy VisitBinMul(const BinaryOperator *E) {
212     return EmitBinMul(EmitBinOps(E));
213   }
214   ComplexPairTy VisitBinAdd(const BinaryOperator *E) {
215     return EmitBinAdd(EmitBinOps(E));
216   }
217   ComplexPairTy VisitBinSub(const BinaryOperator *E) {
218     return EmitBinSub(EmitBinOps(E));
219   }
220   ComplexPairTy VisitBinDiv(const BinaryOperator *E) {
221     return EmitBinDiv(EmitBinOps(E));
222   }
223 
224   // Compound assignments.
225   ComplexPairTy VisitBinAddAssign(const CompoundAssignOperator *E) {
226     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinAdd);
227   }
228   ComplexPairTy VisitBinSubAssign(const CompoundAssignOperator *E) {
229     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinSub);
230   }
231   ComplexPairTy VisitBinMulAssign(const CompoundAssignOperator *E) {
232     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinMul);
233   }
234   ComplexPairTy VisitBinDivAssign(const CompoundAssignOperator *E) {
235     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinDiv);
236   }
237 
238   // GCC rejects rem/and/or/xor for integer complex.
239   // Logical and/or always return int, never complex.
240 
241   // No comparisons produce a complex result.
242   ComplexPairTy VisitBinAssign     (const BinaryOperator *E);
243   ComplexPairTy VisitBinComma      (const BinaryOperator *E);
244 
245 
246   ComplexPairTy VisitConditionalOperator(const ConditionalOperator *CO);
247   ComplexPairTy VisitChooseExpr(ChooseExpr *CE);
248 
249   ComplexPairTy VisitInitListExpr(InitListExpr *E);
250 
251   ComplexPairTy VisitVAArgExpr(VAArgExpr *E);
252 };
253 }  // end anonymous namespace.
254 
255 //===----------------------------------------------------------------------===//
256 //                                Utilities
257 //===----------------------------------------------------------------------===//
258 
259 /// EmitLoadOfComplex - Given an RValue reference for a complex, emit code to
260 /// load the real and imaginary pieces, returning them as Real/Imag.
261 ComplexPairTy ComplexExprEmitter::EmitLoadOfComplex(llvm::Value *SrcPtr,
262                                                     bool isVolatile) {
263   llvm::SmallString<64> Name(SrcPtr->getName().begin(),
264                              SrcPtr->getName().end());
265 
266   llvm::Value *Real=0, *Imag=0;
267 
268   if (!IgnoreReal) {
269     // FIXME: Clean this up once builder takes Twine/StringRef.
270     Name += ".realp";
271     llvm::Value *RealPtr = Builder.CreateStructGEP(SrcPtr, 0,
272                                                    Name.str().str().c_str());
273 
274     Name.pop_back();  // .realp -> .real
275     // FIXME: Clean this up once builder takes Twine/StringRef.
276     Real = Builder.CreateLoad(RealPtr, isVolatile,
277                               Name.str().str().c_str());
278     Name.resize(Name.size()-4); // .real -> .imagp
279   }
280 
281   if (!IgnoreImag) {
282     Name += "imagp";
283 
284     // FIXME: Clean this up once builder takes Twine/StringRef.
285     llvm::Value *ImagPtr = Builder.CreateStructGEP(SrcPtr, 1,
286                                                    Name.str().str().c_str());
287 
288     Name.pop_back();  // .imagp -> .imag
289     // FIXME: Clean this up once builder takes Twine/StringRef.
290     Imag = Builder.CreateLoad(ImagPtr, isVolatile, Name.str().str().c_str());
291   }
292   return ComplexPairTy(Real, Imag);
293 }
294 
295 /// EmitStoreOfComplex - Store the specified real/imag parts into the
296 /// specified value pointer.
297 void ComplexExprEmitter::EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *Ptr,
298                                             bool isVolatile) {
299   llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, "real");
300   llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, "imag");
301 
302   Builder.CreateStore(Val.first, RealPtr, isVolatile);
303   Builder.CreateStore(Val.second, ImagPtr, isVolatile);
304 }
305 
306 
307 
308 //===----------------------------------------------------------------------===//
309 //                            Visitor Methods
310 //===----------------------------------------------------------------------===//
311 
312 ComplexPairTy ComplexExprEmitter::VisitExpr(Expr *E) {
313   CGF.ErrorUnsupported(E, "complex expression");
314   const llvm::Type *EltTy =
315     CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
316   llvm::Value *U = llvm::UndefValue::get(EltTy);
317   return ComplexPairTy(U, U);
318 }
319 
320 ComplexPairTy ComplexExprEmitter::
321 VisitImaginaryLiteral(const ImaginaryLiteral *IL) {
322   llvm::Value *Imag = CGF.EmitScalarExpr(IL->getSubExpr());
323   return
324         ComplexPairTy(llvm::Constant::getNullValue(Imag->getType()), Imag);
325 }
326 
327 
328 ComplexPairTy ComplexExprEmitter::VisitCallExpr(const CallExpr *E) {
329   if (E->getCallReturnType()->isReferenceType())
330     return EmitLoadOfLValue(E);
331 
332   return CGF.EmitCallExpr(E).getComplexVal();
333 }
334 
335 ComplexPairTy ComplexExprEmitter::VisitStmtExpr(const StmtExpr *E) {
336   return CGF.EmitCompoundStmt(*E->getSubStmt(), true).getComplexVal();
337 }
338 
339 /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
340 ComplexPairTy ComplexExprEmitter::EmitComplexToComplexCast(ComplexPairTy Val,
341                                                            QualType SrcType,
342                                                            QualType DestType) {
343   // Get the src/dest element type.
344   SrcType = SrcType->getAs<ComplexType>()->getElementType();
345   DestType = DestType->getAs<ComplexType>()->getElementType();
346 
347   // C99 6.3.1.6: When a value of complex type is converted to another
348   // complex type, both the real and imaginary parts follow the conversion
349   // rules for the corresponding real types.
350   Val.first = CGF.EmitScalarConversion(Val.first, SrcType, DestType);
351   Val.second = CGF.EmitScalarConversion(Val.second, SrcType, DestType);
352   return Val;
353 }
354 
355 ComplexPairTy ComplexExprEmitter::EmitCast(Expr *Op, QualType DestTy) {
356   // Two cases here: cast from (complex to complex) and (scalar to complex).
357   if (Op->getType()->isAnyComplexType())
358     return EmitComplexToComplexCast(Visit(Op), Op->getType(), DestTy);
359 
360   // C99 6.3.1.7: When a value of real type is converted to a complex type, the
361   // real part of the complex result value is determined by the rules of
362   // conversion to the corresponding real type and the imaginary part of the
363   // complex result value is a positive zero or an unsigned zero.
364   llvm::Value *Elt = CGF.EmitScalarExpr(Op);
365 
366   // Convert the input element to the element type of the complex.
367   DestTy = DestTy->getAs<ComplexType>()->getElementType();
368   Elt = CGF.EmitScalarConversion(Elt, Op->getType(), DestTy);
369 
370   // Return (realval, 0).
371   return ComplexPairTy(Elt, llvm::Constant::getNullValue(Elt->getType()));
372 }
373 
374 ComplexPairTy ComplexExprEmitter::VisitPrePostIncDec(const UnaryOperator *E,
375                                                      bool isInc, bool isPre) {
376   LValue LV = CGF.EmitLValue(E->getSubExpr());
377   ComplexPairTy InVal = EmitLoadOfComplex(LV.getAddress(),
378                                           LV.isVolatileQualified());
379 
380   llvm::Value *NextVal;
381   if (isa<llvm::IntegerType>(InVal.first->getType())) {
382     uint64_t AmountVal = isInc ? 1 : -1;
383     NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
384 
385     // Add the inc/dec to the real part.
386     NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
387   } else {
388     QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
389     llvm::APFloat FVal(CGF.getContext().getFloatTypeSemantics(ElemTy), 1);
390     if (!isInc)
391       FVal.changeSign();
392     NextVal = llvm::ConstantFP::get(CGF.getLLVMContext(), FVal);
393 
394     // Add the inc/dec to the real part.
395     NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
396   }
397 
398   ComplexPairTy IncVal(NextVal, InVal.second);
399 
400   // Store the updated result through the lvalue.
401   EmitStoreOfComplex(IncVal, LV.getAddress(), LV.isVolatileQualified());
402 
403   // If this is a postinc, return the value read from memory, otherwise use the
404   // updated value.
405   return isPre ? IncVal : InVal;
406 }
407 
408 ComplexPairTy ComplexExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
409   TestAndClearIgnoreReal();
410   TestAndClearIgnoreImag();
411   TestAndClearIgnoreRealAssign();
412   TestAndClearIgnoreImagAssign();
413   ComplexPairTy Op = Visit(E->getSubExpr());
414 
415   llvm::Value *ResR, *ResI;
416   if (Op.first->getType()->isFloatingPoint()) {
417     ResR = Builder.CreateFNeg(Op.first,  "neg.r");
418     ResI = Builder.CreateFNeg(Op.second, "neg.i");
419   } else {
420     ResR = Builder.CreateNeg(Op.first,  "neg.r");
421     ResI = Builder.CreateNeg(Op.second, "neg.i");
422   }
423   return ComplexPairTy(ResR, ResI);
424 }
425 
426 ComplexPairTy ComplexExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
427   TestAndClearIgnoreReal();
428   TestAndClearIgnoreImag();
429   TestAndClearIgnoreRealAssign();
430   TestAndClearIgnoreImagAssign();
431   // ~(a+ib) = a + i*-b
432   ComplexPairTy Op = Visit(E->getSubExpr());
433   llvm::Value *ResI;
434   if (Op.second->getType()->isFloatingPoint())
435     ResI = Builder.CreateFNeg(Op.second, "conj.i");
436   else
437     ResI = Builder.CreateNeg(Op.second, "conj.i");
438 
439   return ComplexPairTy(Op.first, ResI);
440 }
441 
442 ComplexPairTy ComplexExprEmitter::EmitBinAdd(const BinOpInfo &Op) {
443   llvm::Value *ResR, *ResI;
444 
445   if (Op.LHS.first->getType()->isFloatingPoint()) {
446     ResR = Builder.CreateFAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
447     ResI = Builder.CreateFAdd(Op.LHS.second, Op.RHS.second, "add.i");
448   } else {
449     ResR = Builder.CreateAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
450     ResI = Builder.CreateAdd(Op.LHS.second, Op.RHS.second, "add.i");
451   }
452   return ComplexPairTy(ResR, ResI);
453 }
454 
455 ComplexPairTy ComplexExprEmitter::EmitBinSub(const BinOpInfo &Op) {
456   llvm::Value *ResR, *ResI;
457   if (Op.LHS.first->getType()->isFloatingPoint()) {
458     ResR = Builder.CreateFSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
459     ResI = Builder.CreateFSub(Op.LHS.second, Op.RHS.second, "sub.i");
460   } else {
461     ResR = Builder.CreateSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
462     ResI = Builder.CreateSub(Op.LHS.second, Op.RHS.second, "sub.i");
463   }
464   return ComplexPairTy(ResR, ResI);
465 }
466 
467 
468 ComplexPairTy ComplexExprEmitter::EmitBinMul(const BinOpInfo &Op) {
469   using llvm::Value;
470   Value *ResR, *ResI;
471 
472   if (Op.LHS.first->getType()->isFloatingPoint()) {
473     Value *ResRl = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul.rl");
474     Value *ResRr = Builder.CreateFMul(Op.LHS.second, Op.RHS.second,"mul.rr");
475     ResR  = Builder.CreateFSub(ResRl, ResRr, "mul.r");
476 
477     Value *ResIl = Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul.il");
478     Value *ResIr = Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul.ir");
479     ResI  = Builder.CreateFAdd(ResIl, ResIr, "mul.i");
480   } else {
481     Value *ResRl = Builder.CreateMul(Op.LHS.first, Op.RHS.first, "mul.rl");
482     Value *ResRr = Builder.CreateMul(Op.LHS.second, Op.RHS.second,"mul.rr");
483     ResR  = Builder.CreateSub(ResRl, ResRr, "mul.r");
484 
485     Value *ResIl = Builder.CreateMul(Op.LHS.second, Op.RHS.first, "mul.il");
486     Value *ResIr = Builder.CreateMul(Op.LHS.first, Op.RHS.second, "mul.ir");
487     ResI  = Builder.CreateAdd(ResIl, ResIr, "mul.i");
488   }
489   return ComplexPairTy(ResR, ResI);
490 }
491 
492 ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
493   llvm::Value *LHSr = Op.LHS.first, *LHSi = Op.LHS.second;
494   llvm::Value *RHSr = Op.RHS.first, *RHSi = Op.RHS.second;
495 
496 
497   llvm::Value *DSTr, *DSTi;
498   if (Op.LHS.first->getType()->isFloatingPoint()) {
499     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
500     llvm::Value *Tmp1 = Builder.CreateFMul(LHSr, RHSr, "tmp"); // a*c
501     llvm::Value *Tmp2 = Builder.CreateFMul(LHSi, RHSi, "tmp"); // b*d
502     llvm::Value *Tmp3 = Builder.CreateFAdd(Tmp1, Tmp2, "tmp"); // ac+bd
503 
504     llvm::Value *Tmp4 = Builder.CreateFMul(RHSr, RHSr, "tmp"); // c*c
505     llvm::Value *Tmp5 = Builder.CreateFMul(RHSi, RHSi, "tmp"); // d*d
506     llvm::Value *Tmp6 = Builder.CreateFAdd(Tmp4, Tmp5, "tmp"); // cc+dd
507 
508     llvm::Value *Tmp7 = Builder.CreateFMul(LHSi, RHSr, "tmp"); // b*c
509     llvm::Value *Tmp8 = Builder.CreateFMul(LHSr, RHSi, "tmp"); // a*d
510     llvm::Value *Tmp9 = Builder.CreateFSub(Tmp7, Tmp8, "tmp"); // bc-ad
511 
512     DSTr = Builder.CreateFDiv(Tmp3, Tmp6, "tmp");
513     DSTi = Builder.CreateFDiv(Tmp9, Tmp6, "tmp");
514   } else {
515     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
516     llvm::Value *Tmp1 = Builder.CreateMul(LHSr, RHSr, "tmp"); // a*c
517     llvm::Value *Tmp2 = Builder.CreateMul(LHSi, RHSi, "tmp"); // b*d
518     llvm::Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2, "tmp"); // ac+bd
519 
520     llvm::Value *Tmp4 = Builder.CreateMul(RHSr, RHSr, "tmp"); // c*c
521     llvm::Value *Tmp5 = Builder.CreateMul(RHSi, RHSi, "tmp"); // d*d
522     llvm::Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5, "tmp"); // cc+dd
523 
524     llvm::Value *Tmp7 = Builder.CreateMul(LHSi, RHSr, "tmp"); // b*c
525     llvm::Value *Tmp8 = Builder.CreateMul(LHSr, RHSi, "tmp"); // a*d
526     llvm::Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8, "tmp"); // bc-ad
527 
528     if (Op.Ty->getAs<ComplexType>()->getElementType()->isUnsignedIntegerType()) {
529       DSTr = Builder.CreateUDiv(Tmp3, Tmp6, "tmp");
530       DSTi = Builder.CreateUDiv(Tmp9, Tmp6, "tmp");
531     } else {
532       DSTr = Builder.CreateSDiv(Tmp3, Tmp6, "tmp");
533       DSTi = Builder.CreateSDiv(Tmp9, Tmp6, "tmp");
534     }
535   }
536 
537   return ComplexPairTy(DSTr, DSTi);
538 }
539 
540 ComplexExprEmitter::BinOpInfo
541 ComplexExprEmitter::EmitBinOps(const BinaryOperator *E) {
542   TestAndClearIgnoreReal();
543   TestAndClearIgnoreImag();
544   TestAndClearIgnoreRealAssign();
545   TestAndClearIgnoreImagAssign();
546   BinOpInfo Ops;
547   Ops.LHS = Visit(E->getLHS());
548   Ops.RHS = Visit(E->getRHS());
549   Ops.Ty = E->getType();
550   return Ops;
551 }
552 
553 
554 // Compound assignments.
555 ComplexPairTy ComplexExprEmitter::
556 EmitCompoundAssign(const CompoundAssignOperator *E,
557                    ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&)){
558   TestAndClearIgnoreReal();
559   TestAndClearIgnoreImag();
560   bool ignreal = TestAndClearIgnoreRealAssign();
561   bool ignimag = TestAndClearIgnoreImagAssign();
562   QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType();
563 
564   BinOpInfo OpInfo;
565 
566   // Load the RHS and LHS operands.
567   // __block variables need to have the rhs evaluated first, plus this should
568   // improve codegen a little.  It is possible for the RHS to be complex or
569   // scalar.
570   OpInfo.Ty = E->getComputationResultType();
571   OpInfo.RHS = EmitCast(E->getRHS(), OpInfo.Ty);
572 
573   LValue LHSLV = CGF.EmitLValue(E->getLHS());
574 
575 
576   // We know the LHS is a complex lvalue.
577   OpInfo.LHS=EmitLoadOfComplex(LHSLV.getAddress(), LHSLV.isVolatileQualified());
578   OpInfo.LHS=EmitComplexToComplexCast(OpInfo.LHS, LHSTy, OpInfo.Ty);
579 
580   // Expand the binary operator.
581   ComplexPairTy Result = (this->*Func)(OpInfo);
582 
583   // Truncate the result back to the LHS type.
584   Result = EmitComplexToComplexCast(Result, OpInfo.Ty, LHSTy);
585 
586   // Store the result value into the LHS lvalue.
587   EmitStoreOfComplex(Result, LHSLV.getAddress(), LHSLV.isVolatileQualified());
588   // And now return the LHS
589   IgnoreReal = ignreal;
590   IgnoreImag = ignimag;
591   IgnoreRealAssign = ignreal;
592   IgnoreImagAssign = ignimag;
593   return EmitLoadOfComplex(LHSLV.getAddress(), LHSLV.isVolatileQualified());
594 }
595 
596 ComplexPairTy ComplexExprEmitter::VisitBinAssign(const BinaryOperator *E) {
597   TestAndClearIgnoreReal();
598   TestAndClearIgnoreImag();
599   bool ignreal = TestAndClearIgnoreRealAssign();
600   bool ignimag = TestAndClearIgnoreImagAssign();
601   assert(CGF.getContext().getCanonicalType(E->getLHS()->getType()) ==
602          CGF.getContext().getCanonicalType(E->getRHS()->getType()) &&
603          "Invalid assignment");
604   // Emit the RHS.
605   ComplexPairTy Val = Visit(E->getRHS());
606 
607   // Compute the address to store into.
608   LValue LHS = CGF.EmitLValue(E->getLHS());
609 
610   // Store into it, if simple.
611   if (LHS.isSimple()) {
612     EmitStoreOfComplex(Val, LHS.getAddress(), LHS.isVolatileQualified());
613 
614     // And now return the LHS
615     IgnoreReal = ignreal;
616     IgnoreImag = ignimag;
617     IgnoreRealAssign = ignreal;
618     IgnoreImagAssign = ignimag;
619     return EmitLoadOfComplex(LHS.getAddress(), LHS.isVolatileQualified());
620   }
621 
622   // Otherwise we must have a property setter (no complex vector/bitfields).
623   if (LHS.isPropertyRef())
624     CGF.EmitObjCPropertySet(LHS.getPropertyRefExpr(), RValue::getComplex(Val));
625   else
626     CGF.EmitObjCPropertySet(LHS.getKVCRefExpr(), RValue::getComplex(Val));
627 
628   // There is no reload after a store through a method, but we need to restore
629   // the Ignore* flags.
630   IgnoreReal = ignreal;
631   IgnoreImag = ignimag;
632   IgnoreRealAssign = ignreal;
633   IgnoreImagAssign = ignimag;
634   return Val;
635 }
636 
637 ComplexPairTy ComplexExprEmitter::VisitBinComma(const BinaryOperator *E) {
638   CGF.EmitStmt(E->getLHS());
639   CGF.EnsureInsertPoint();
640   return Visit(E->getRHS());
641 }
642 
643 ComplexPairTy ComplexExprEmitter::
644 VisitConditionalOperator(const ConditionalOperator *E) {
645   TestAndClearIgnoreReal();
646   TestAndClearIgnoreImag();
647   TestAndClearIgnoreRealAssign();
648   TestAndClearIgnoreImagAssign();
649   llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
650   llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
651   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
652 
653   llvm::Value *Cond = CGF.EvaluateExprAsBool(E->getCond());
654   Builder.CreateCondBr(Cond, LHSBlock, RHSBlock);
655 
656   CGF.EmitBlock(LHSBlock);
657 
658   // Handle the GNU extension for missing LHS.
659   assert(E->getLHS() && "Must have LHS for complex value");
660 
661   ComplexPairTy LHS = Visit(E->getLHS());
662   LHSBlock = Builder.GetInsertBlock();
663   CGF.EmitBranch(ContBlock);
664 
665   CGF.EmitBlock(RHSBlock);
666 
667   ComplexPairTy RHS = Visit(E->getRHS());
668   RHSBlock = Builder.GetInsertBlock();
669   CGF.EmitBranch(ContBlock);
670 
671   CGF.EmitBlock(ContBlock);
672 
673   // Create a PHI node for the real part.
674   llvm::PHINode *RealPN = Builder.CreatePHI(LHS.first->getType(), "cond.r");
675   RealPN->reserveOperandSpace(2);
676   RealPN->addIncoming(LHS.first, LHSBlock);
677   RealPN->addIncoming(RHS.first, RHSBlock);
678 
679   // Create a PHI node for the imaginary part.
680   llvm::PHINode *ImagPN = Builder.CreatePHI(LHS.first->getType(), "cond.i");
681   ImagPN->reserveOperandSpace(2);
682   ImagPN->addIncoming(LHS.second, LHSBlock);
683   ImagPN->addIncoming(RHS.second, RHSBlock);
684 
685   return ComplexPairTy(RealPN, ImagPN);
686 }
687 
688 ComplexPairTy ComplexExprEmitter::VisitChooseExpr(ChooseExpr *E) {
689   return Visit(E->getChosenSubExpr(CGF.getContext()));
690 }
691 
692 ComplexPairTy ComplexExprEmitter::VisitInitListExpr(InitListExpr *E) {
693     bool Ignore = TestAndClearIgnoreReal();
694     (void)Ignore;
695     assert (Ignore == false && "init list ignored");
696     Ignore = TestAndClearIgnoreImag();
697     (void)Ignore;
698     assert (Ignore == false && "init list ignored");
699   if (E->getNumInits())
700     return Visit(E->getInit(0));
701 
702   // Empty init list intializes to null
703   QualType Ty = E->getType()->getAs<ComplexType>()->getElementType();
704   const llvm::Type* LTy = CGF.ConvertType(Ty);
705   llvm::Value* zeroConstant = llvm::Constant::getNullValue(LTy);
706   return ComplexPairTy(zeroConstant, zeroConstant);
707 }
708 
709 ComplexPairTy ComplexExprEmitter::VisitVAArgExpr(VAArgExpr *E) {
710   llvm::Value *ArgValue = CGF.EmitVAListRef(E->getSubExpr());
711   llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, E->getType());
712 
713   if (!ArgPtr) {
714     CGF.ErrorUnsupported(E, "complex va_arg expression");
715     const llvm::Type *EltTy =
716       CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
717     llvm::Value *U = llvm::UndefValue::get(EltTy);
718     return ComplexPairTy(U, U);
719   }
720 
721   // FIXME Volatility.
722   return EmitLoadOfComplex(ArgPtr, false);
723 }
724 
725 //===----------------------------------------------------------------------===//
726 //                         Entry Point into this File
727 //===----------------------------------------------------------------------===//
728 
729 /// EmitComplexExpr - Emit the computation of the specified expression of
730 /// complex type, ignoring the result.
731 ComplexPairTy CodeGenFunction::EmitComplexExpr(const Expr *E, bool IgnoreReal,
732                                                bool IgnoreImag, bool IgnoreRealAssign, bool IgnoreImagAssign) {
733   assert(E && E->getType()->isAnyComplexType() &&
734          "Invalid complex expression to emit");
735 
736   return ComplexExprEmitter(*this, IgnoreReal, IgnoreImag, IgnoreRealAssign,
737                             IgnoreImagAssign)
738     .Visit(const_cast<Expr*>(E));
739 }
740 
741 /// EmitComplexExprIntoAddr - Emit the computation of the specified expression
742 /// of complex type, storing into the specified Value*.
743 void CodeGenFunction::EmitComplexExprIntoAddr(const Expr *E,
744                                               llvm::Value *DestAddr,
745                                               bool DestIsVolatile) {
746   assert(E && E->getType()->isAnyComplexType() &&
747          "Invalid complex expression to emit");
748   ComplexExprEmitter Emitter(*this);
749   ComplexPairTy Val = Emitter.Visit(const_cast<Expr*>(E));
750   Emitter.EmitStoreOfComplex(Val, DestAddr, DestIsVolatile);
751 }
752 
753 /// StoreComplexToAddr - Store a complex number into the specified address.
754 void CodeGenFunction::StoreComplexToAddr(ComplexPairTy V,
755                                          llvm::Value *DestAddr,
756                                          bool DestIsVolatile) {
757   ComplexExprEmitter(*this).EmitStoreOfComplex(V, DestAddr, DestIsVolatile);
758 }
759 
760 /// LoadComplexFromAddr - Load a complex number from the specified address.
761 ComplexPairTy CodeGenFunction::LoadComplexFromAddr(llvm::Value *SrcAddr,
762                                                    bool SrcIsVolatile) {
763   return ComplexExprEmitter(*this).EmitLoadOfComplex(SrcAddr, SrcIsVolatile);
764 }
765