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 #include "llvm/Support/Compiler.h"
22 using namespace clang;
23 using namespace CodeGen;
24 
25 //===----------------------------------------------------------------------===//
26 //                        Complex Expression Emitter
27 //===----------------------------------------------------------------------===//
28 
29 typedef CodeGenFunction::ComplexPairTy ComplexPairTy;
30 
31 namespace  {
32 class VISIBILITY_HIDDEN ComplexExprEmitter
33   : public StmtVisitor<ComplexExprEmitter, ComplexPairTy> {
34   CodeGenFunction &CGF;
35   CGBuilderTy &Builder;
36   // True is we should ignore the value of a
37   bool IgnoreReal;
38   bool IgnoreImag;
39   // True if we should ignore the value of a=b
40   bool IgnoreRealAssign;
41   bool IgnoreImagAssign;
42 public:
43   ComplexExprEmitter(CodeGenFunction &cgf, bool ir=false, bool ii=false,
44                      bool irn=false, bool iin=false)
45     : CGF(cgf), Builder(CGF.Builder), IgnoreReal(ir), IgnoreImag(ii),
46     IgnoreRealAssign(irn), IgnoreImagAssign(iin) {
47   }
48 
49 
50   //===--------------------------------------------------------------------===//
51   //                               Utilities
52   //===--------------------------------------------------------------------===//
53 
54   bool TestAndClearIgnoreReal() {
55     bool I = IgnoreReal;
56     IgnoreReal = false;
57     return I;
58   }
59   bool TestAndClearIgnoreImag() {
60     bool I = IgnoreImag;
61     IgnoreImag = false;
62     return I;
63   }
64   bool TestAndClearIgnoreRealAssign() {
65     bool I = IgnoreRealAssign;
66     IgnoreRealAssign = false;
67     return I;
68   }
69   bool TestAndClearIgnoreImagAssign() {
70     bool I = IgnoreImagAssign;
71     IgnoreImagAssign = false;
72     return I;
73   }
74 
75   /// EmitLoadOfLValue - Given an expression with complex type that represents a
76   /// value l-value, this method emits the address of the l-value, then loads
77   /// and returns the result.
78   ComplexPairTy EmitLoadOfLValue(const Expr *E) {
79     LValue LV = CGF.EmitLValue(E);
80     if (LV.isSimple())
81       return EmitLoadOfComplex(LV.getAddress(), LV.isVolatileQualified());
82 
83     if (LV.isPropertyRef())
84       return CGF.EmitObjCPropertyGet(LV.getPropertyRefExpr()).getComplexVal();
85 
86     assert(LV.isKVCRef() && "Unknown LValue type!");
87     return CGF.EmitObjCPropertyGet(LV.getKVCRefExpr()).getComplexVal();
88   }
89 
90   /// EmitLoadOfComplex - Given a pointer to a complex value, emit code to load
91   /// the real and imaginary pieces.
92   ComplexPairTy EmitLoadOfComplex(llvm::Value *SrcPtr, bool isVolatile);
93 
94   /// EmitStoreOfComplex - Store the specified real/imag parts into the
95   /// specified value pointer.
96   void EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *ResPtr, bool isVol);
97 
98   /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
99   ComplexPairTy EmitComplexToComplexCast(ComplexPairTy Val, QualType SrcType,
100                                          QualType DestType);
101 
102   //===--------------------------------------------------------------------===//
103   //                            Visitor Methods
104   //===--------------------------------------------------------------------===//
105 
106   ComplexPairTy VisitStmt(Stmt *S) {
107     S->dump(CGF.getContext().getSourceManager());
108     assert(0 && "Stmt can't have complex result type!");
109     return ComplexPairTy();
110   }
111   ComplexPairTy VisitExpr(Expr *S);
112   ComplexPairTy VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr());}
113   ComplexPairTy VisitImaginaryLiteral(const ImaginaryLiteral *IL);
114 
115   // l-values.
116   ComplexPairTy VisitDeclRefExpr(const Expr *E) { return EmitLoadOfLValue(E); }
117   ComplexPairTy VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
118     return EmitLoadOfLValue(E);
119   }
120   ComplexPairTy VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) {
121     return EmitLoadOfLValue(E);
122   }
123   ComplexPairTy VisitObjCKVCRefExpr(ObjCKVCRefExpr *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()->getAsComplexType()->getElementType();
184     llvm::Constant *Null =
185                        CGF.getLLVMContext().getNullValue(CGF.ConvertType(Elem));
186     return ComplexPairTy(Null, Null);
187   }
188   ComplexPairTy VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
189     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
190     QualType Elem = E->getType()->getAsComplexType()->getElementType();
191     llvm::Constant *Null =
192                        CGF.getLLVMContext().getNullValue(CGF.ConvertType(Elem));
193     return ComplexPairTy(Null, Null);
194   }
195 
196   struct BinOpInfo {
197     ComplexPairTy LHS;
198     ComplexPairTy RHS;
199     QualType Ty;  // Computation Type.
200   };
201 
202   BinOpInfo EmitBinOps(const BinaryOperator *E);
203   ComplexPairTy EmitCompoundAssign(const CompoundAssignOperator *E,
204                                    ComplexPairTy (ComplexExprEmitter::*Func)
205                                    (const BinOpInfo &));
206 
207   ComplexPairTy EmitBinAdd(const BinOpInfo &Op);
208   ComplexPairTy EmitBinSub(const BinOpInfo &Op);
209   ComplexPairTy EmitBinMul(const BinOpInfo &Op);
210   ComplexPairTy EmitBinDiv(const BinOpInfo &Op);
211 
212   ComplexPairTy VisitBinMul(const BinaryOperator *E) {
213     return EmitBinMul(EmitBinOps(E));
214   }
215   ComplexPairTy VisitBinAdd(const BinaryOperator *E) {
216     return EmitBinAdd(EmitBinOps(E));
217   }
218   ComplexPairTy VisitBinSub(const BinaryOperator *E) {
219     return EmitBinSub(EmitBinOps(E));
220   }
221   ComplexPairTy VisitBinDiv(const BinaryOperator *E) {
222     return EmitBinDiv(EmitBinOps(E));
223   }
224 
225   // Compound assignments.
226   ComplexPairTy VisitBinAddAssign(const CompoundAssignOperator *E) {
227     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinAdd);
228   }
229   ComplexPairTy VisitBinSubAssign(const CompoundAssignOperator *E) {
230     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinSub);
231   }
232   ComplexPairTy VisitBinMulAssign(const CompoundAssignOperator *E) {
233     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinMul);
234   }
235   ComplexPairTy VisitBinDivAssign(const CompoundAssignOperator *E) {
236     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinDiv);
237   }
238 
239   // GCC rejects rem/and/or/xor for integer complex.
240   // Logical and/or always return int, never complex.
241 
242   // No comparisons produce a complex result.
243   ComplexPairTy VisitBinAssign     (const BinaryOperator *E);
244   ComplexPairTy VisitBinComma      (const BinaryOperator *E);
245 
246 
247   ComplexPairTy VisitConditionalOperator(const ConditionalOperator *CO);
248   ComplexPairTy VisitChooseExpr(ChooseExpr *CE);
249 
250   ComplexPairTy VisitInitListExpr(InitListExpr *E);
251 
252   ComplexPairTy VisitVAArgExpr(VAArgExpr *E);
253 };
254 }  // end anonymous namespace.
255 
256 //===----------------------------------------------------------------------===//
257 //                                Utilities
258 //===----------------------------------------------------------------------===//
259 
260 /// EmitLoadOfComplex - Given an RValue reference for a complex, emit code to
261 /// load the real and imaginary pieces, returning them as Real/Imag.
262 ComplexPairTy ComplexExprEmitter::EmitLoadOfComplex(llvm::Value *SrcPtr,
263                                                     bool isVolatile) {
264   llvm::SmallString<64> Name(SrcPtr->getName().begin(),
265                              SrcPtr->getName().end());
266 
267   llvm::Value *Real=0, *Imag=0;
268 
269   if (!IgnoreReal) {
270     Name += ".realp";
271     llvm::Value *RealPtr = Builder.CreateStructGEP(SrcPtr, 0, Name.c_str());
272 
273     Name.pop_back();  // .realp -> .real
274     Real = Builder.CreateLoad(RealPtr, isVolatile, Name.c_str());
275     Name.resize(Name.size()-4); // .real -> .imagp
276   }
277 
278   if (!IgnoreImag) {
279     Name += "imagp";
280 
281     llvm::Value *ImagPtr = Builder.CreateStructGEP(SrcPtr, 1, Name.c_str());
282 
283     Name.pop_back();  // .imagp -> .imag
284     Imag = Builder.CreateLoad(ImagPtr, isVolatile, Name.c_str());
285   }
286   return ComplexPairTy(Real, Imag);
287 }
288 
289 /// EmitStoreOfComplex - Store the specified real/imag parts into the
290 /// specified value pointer.
291 void ComplexExprEmitter::EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *Ptr,
292                                             bool isVolatile) {
293   llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, "real");
294   llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, "imag");
295 
296   Builder.CreateStore(Val.first, RealPtr, isVolatile);
297   Builder.CreateStore(Val.second, ImagPtr, isVolatile);
298 }
299 
300 
301 
302 //===----------------------------------------------------------------------===//
303 //                            Visitor Methods
304 //===----------------------------------------------------------------------===//
305 
306 ComplexPairTy ComplexExprEmitter::VisitExpr(Expr *E) {
307   CGF.ErrorUnsupported(E, "complex expression");
308   const llvm::Type *EltTy =
309     CGF.ConvertType(E->getType()->getAsComplexType()->getElementType());
310   llvm::Value *U = llvm::UndefValue::get(EltTy);
311   return ComplexPairTy(U, U);
312 }
313 
314 ComplexPairTy ComplexExprEmitter::
315 VisitImaginaryLiteral(const ImaginaryLiteral *IL) {
316   llvm::Value *Imag = CGF.EmitScalarExpr(IL->getSubExpr());
317   return
318         ComplexPairTy(CGF.getLLVMContext().getNullValue(Imag->getType()), Imag);
319 }
320 
321 
322 ComplexPairTy ComplexExprEmitter::VisitCallExpr(const CallExpr *E) {
323   if (E->getCallReturnType()->isReferenceType())
324     return EmitLoadOfLValue(E);
325 
326   return CGF.EmitCallExpr(E).getComplexVal();
327 }
328 
329 ComplexPairTy ComplexExprEmitter::VisitStmtExpr(const StmtExpr *E) {
330   return CGF.EmitCompoundStmt(*E->getSubStmt(), true).getComplexVal();
331 }
332 
333 /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
334 ComplexPairTy ComplexExprEmitter::EmitComplexToComplexCast(ComplexPairTy Val,
335                                                            QualType SrcType,
336                                                            QualType DestType) {
337   // Get the src/dest element type.
338   SrcType = SrcType->getAsComplexType()->getElementType();
339   DestType = DestType->getAsComplexType()->getElementType();
340 
341   // C99 6.3.1.6: When a value of complex type is converted to another
342   // complex type, both the real and imaginary parts follow the conversion
343   // rules for the corresponding real types.
344   Val.first = CGF.EmitScalarConversion(Val.first, SrcType, DestType);
345   Val.second = CGF.EmitScalarConversion(Val.second, SrcType, DestType);
346   return Val;
347 }
348 
349 ComplexPairTy ComplexExprEmitter::EmitCast(Expr *Op, QualType DestTy) {
350   // Two cases here: cast from (complex to complex) and (scalar to complex).
351   if (Op->getType()->isAnyComplexType())
352     return EmitComplexToComplexCast(Visit(Op), Op->getType(), DestTy);
353 
354   // C99 6.3.1.7: When a value of real type is converted to a complex type, the
355   // real part of the complex result value is determined by the rules of
356   // conversion to the corresponding real type and the imaginary part of the
357   // complex result value is a positive zero or an unsigned zero.
358   llvm::Value *Elt = CGF.EmitScalarExpr(Op);
359 
360   // Convert the input element to the element type of the complex.
361   DestTy = DestTy->getAsComplexType()->getElementType();
362   Elt = CGF.EmitScalarConversion(Elt, Op->getType(), DestTy);
363 
364   // Return (realval, 0).
365   return ComplexPairTy(Elt, CGF.getLLVMContext().getNullValue(Elt->getType()));
366 }
367 
368 ComplexPairTy ComplexExprEmitter::VisitPrePostIncDec(const UnaryOperator *E,
369                                                      bool isInc, bool isPre) {
370   LValue LV = CGF.EmitLValue(E->getSubExpr());
371   ComplexPairTy InVal = EmitLoadOfComplex(LV.getAddress(),
372                                           LV.isVolatileQualified());
373 
374   llvm::Value *NextVal;
375   if (isa<llvm::IntegerType>(InVal.first->getType())) {
376     uint64_t AmountVal = isInc ? 1 : -1;
377     NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
378 
379     // Add the inc/dec to the real part.
380     NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
381   } else {
382     QualType ElemTy = E->getType()->getAsComplexType()->getElementType();
383     llvm::APFloat FVal(CGF.getContext().getFloatTypeSemantics(ElemTy), 1);
384     if (!isInc)
385       FVal.changeSign();
386     NextVal = llvm::ConstantFP::get(CGF.getLLVMContext(), FVal);
387 
388     // Add the inc/dec to the real part.
389     NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
390   }
391 
392   ComplexPairTy IncVal(NextVal, InVal.second);
393 
394   // Store the updated result through the lvalue.
395   EmitStoreOfComplex(IncVal, LV.getAddress(), LV.isVolatileQualified());
396 
397   // If this is a postinc, return the value read from memory, otherwise use the
398   // updated value.
399   return isPre ? IncVal : InVal;
400 }
401 
402 ComplexPairTy ComplexExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
403   TestAndClearIgnoreReal();
404   TestAndClearIgnoreImag();
405   TestAndClearIgnoreRealAssign();
406   TestAndClearIgnoreImagAssign();
407   ComplexPairTy Op = Visit(E->getSubExpr());
408 
409   llvm::Value *ResR, *ResI;
410   if (Op.first->getType()->isFloatingPoint()) {
411     ResR = Builder.CreateFNeg(Op.first,  "neg.r");
412     ResI = Builder.CreateFNeg(Op.second, "neg.i");
413   } else {
414     ResR = Builder.CreateNeg(Op.first,  "neg.r");
415     ResI = Builder.CreateNeg(Op.second, "neg.i");
416   }
417   return ComplexPairTy(ResR, ResI);
418 }
419 
420 ComplexPairTy ComplexExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
421   TestAndClearIgnoreReal();
422   TestAndClearIgnoreImag();
423   TestAndClearIgnoreRealAssign();
424   TestAndClearIgnoreImagAssign();
425   // ~(a+ib) = a + i*-b
426   ComplexPairTy Op = Visit(E->getSubExpr());
427   llvm::Value *ResI;
428   if (Op.second->getType()->isFloatingPoint())
429     ResI = Builder.CreateFNeg(Op.second, "conj.i");
430   else
431     ResI = Builder.CreateNeg(Op.second, "conj.i");
432 
433   return ComplexPairTy(Op.first, ResI);
434 }
435 
436 ComplexPairTy ComplexExprEmitter::EmitBinAdd(const BinOpInfo &Op) {
437   llvm::Value *ResR, *ResI;
438 
439   if (Op.LHS.first->getType()->isFloatingPoint()) {
440     ResR = Builder.CreateFAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
441     ResI = Builder.CreateFAdd(Op.LHS.second, Op.RHS.second, "add.i");
442   } else {
443     ResR = Builder.CreateAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
444     ResI = Builder.CreateAdd(Op.LHS.second, Op.RHS.second, "add.i");
445   }
446   return ComplexPairTy(ResR, ResI);
447 }
448 
449 ComplexPairTy ComplexExprEmitter::EmitBinSub(const BinOpInfo &Op) {
450   llvm::Value *ResR, *ResI;
451   if (Op.LHS.first->getType()->isFloatingPoint()) {
452     ResR = Builder.CreateFSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
453     ResI = Builder.CreateFSub(Op.LHS.second, Op.RHS.second, "sub.i");
454   } else {
455     ResR = Builder.CreateSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
456     ResI = Builder.CreateSub(Op.LHS.second, Op.RHS.second, "sub.i");
457   }
458   return ComplexPairTy(ResR, ResI);
459 }
460 
461 
462 ComplexPairTy ComplexExprEmitter::EmitBinMul(const BinOpInfo &Op) {
463   using llvm::Value;
464   Value *ResR, *ResI;
465 
466   if (Op.LHS.first->getType()->isFloatingPoint()) {
467     Value *ResRl = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul.rl");
468     Value *ResRr = Builder.CreateFMul(Op.LHS.second, Op.RHS.second,"mul.rr");
469     ResR  = Builder.CreateFSub(ResRl, ResRr, "mul.r");
470 
471     Value *ResIl = Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul.il");
472     Value *ResIr = Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul.ir");
473     ResI  = Builder.CreateFAdd(ResIl, ResIr, "mul.i");
474   } else {
475     Value *ResRl = Builder.CreateMul(Op.LHS.first, Op.RHS.first, "mul.rl");
476     Value *ResRr = Builder.CreateMul(Op.LHS.second, Op.RHS.second,"mul.rr");
477     ResR  = Builder.CreateSub(ResRl, ResRr, "mul.r");
478 
479     Value *ResIl = Builder.CreateMul(Op.LHS.second, Op.RHS.first, "mul.il");
480     Value *ResIr = Builder.CreateMul(Op.LHS.first, Op.RHS.second, "mul.ir");
481     ResI  = Builder.CreateAdd(ResIl, ResIr, "mul.i");
482   }
483   return ComplexPairTy(ResR, ResI);
484 }
485 
486 ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
487   llvm::Value *LHSr = Op.LHS.first, *LHSi = Op.LHS.second;
488   llvm::Value *RHSr = Op.RHS.first, *RHSi = Op.RHS.second;
489 
490 
491   llvm::Value *DSTr, *DSTi;
492   if (Op.LHS.first->getType()->isFloatingPoint()) {
493     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
494     llvm::Value *Tmp1 = Builder.CreateFMul(LHSr, RHSr, "tmp"); // a*c
495     llvm::Value *Tmp2 = Builder.CreateFMul(LHSi, RHSi, "tmp"); // b*d
496     llvm::Value *Tmp3 = Builder.CreateFAdd(Tmp1, Tmp2, "tmp"); // ac+bd
497 
498     llvm::Value *Tmp4 = Builder.CreateFMul(RHSr, RHSr, "tmp"); // c*c
499     llvm::Value *Tmp5 = Builder.CreateFMul(RHSi, RHSi, "tmp"); // d*d
500     llvm::Value *Tmp6 = Builder.CreateFAdd(Tmp4, Tmp5, "tmp"); // cc+dd
501 
502     llvm::Value *Tmp7 = Builder.CreateFMul(LHSi, RHSr, "tmp"); // b*c
503     llvm::Value *Tmp8 = Builder.CreateFMul(LHSr, RHSi, "tmp"); // a*d
504     llvm::Value *Tmp9 = Builder.CreateFSub(Tmp7, Tmp8, "tmp"); // bc-ad
505 
506     DSTr = Builder.CreateFDiv(Tmp3, Tmp6, "tmp");
507     DSTi = Builder.CreateFDiv(Tmp9, Tmp6, "tmp");
508   } else {
509     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
510     llvm::Value *Tmp1 = Builder.CreateMul(LHSr, RHSr, "tmp"); // a*c
511     llvm::Value *Tmp2 = Builder.CreateMul(LHSi, RHSi, "tmp"); // b*d
512     llvm::Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2, "tmp"); // ac+bd
513 
514     llvm::Value *Tmp4 = Builder.CreateMul(RHSr, RHSr, "tmp"); // c*c
515     llvm::Value *Tmp5 = Builder.CreateMul(RHSi, RHSi, "tmp"); // d*d
516     llvm::Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5, "tmp"); // cc+dd
517 
518     llvm::Value *Tmp7 = Builder.CreateMul(LHSi, RHSr, "tmp"); // b*c
519     llvm::Value *Tmp8 = Builder.CreateMul(LHSr, RHSi, "tmp"); // a*d
520     llvm::Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8, "tmp"); // bc-ad
521 
522     if (Op.Ty->getAsComplexType()->getElementType()->isUnsignedIntegerType()) {
523       DSTr = Builder.CreateUDiv(Tmp3, Tmp6, "tmp");
524       DSTi = Builder.CreateUDiv(Tmp9, Tmp6, "tmp");
525     } else {
526       DSTr = Builder.CreateSDiv(Tmp3, Tmp6, "tmp");
527       DSTi = Builder.CreateSDiv(Tmp9, Tmp6, "tmp");
528     }
529   }
530 
531   return ComplexPairTy(DSTr, DSTi);
532 }
533 
534 ComplexExprEmitter::BinOpInfo
535 ComplexExprEmitter::EmitBinOps(const BinaryOperator *E) {
536   TestAndClearIgnoreReal();
537   TestAndClearIgnoreImag();
538   TestAndClearIgnoreRealAssign();
539   TestAndClearIgnoreImagAssign();
540   BinOpInfo Ops;
541   Ops.LHS = Visit(E->getLHS());
542   Ops.RHS = Visit(E->getRHS());
543   Ops.Ty = E->getType();
544   return Ops;
545 }
546 
547 
548 // Compound assignments.
549 ComplexPairTy ComplexExprEmitter::
550 EmitCompoundAssign(const CompoundAssignOperator *E,
551                    ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&)){
552   TestAndClearIgnoreReal();
553   TestAndClearIgnoreImag();
554   bool ignreal = TestAndClearIgnoreRealAssign();
555   bool ignimag = TestAndClearIgnoreImagAssign();
556   QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType();
557 
558   BinOpInfo OpInfo;
559 
560   // Load the RHS and LHS operands.
561   // __block variables need to have the rhs evaluated first, plus this should
562   // improve codegen a little.  It is possible for the RHS to be complex or
563   // scalar.
564   OpInfo.Ty = E->getComputationResultType();
565   OpInfo.RHS = EmitCast(E->getRHS(), OpInfo.Ty);
566 
567   LValue LHSLV = CGF.EmitLValue(E->getLHS());
568 
569 
570   // We know the LHS is a complex lvalue.
571   OpInfo.LHS=EmitLoadOfComplex(LHSLV.getAddress(),LHSLV.isVolatileQualified());
572   OpInfo.LHS=EmitComplexToComplexCast(OpInfo.LHS, LHSTy, OpInfo.Ty);
573 
574   // Expand the binary operator.
575   ComplexPairTy Result = (this->*Func)(OpInfo);
576 
577   // Truncate the result back to the LHS type.
578   Result = EmitComplexToComplexCast(Result, OpInfo.Ty, LHSTy);
579 
580   // Store the result value into the LHS lvalue.
581   EmitStoreOfComplex(Result, LHSLV.getAddress(), LHSLV.isVolatileQualified());
582   // And now return the LHS
583   IgnoreReal = ignreal;
584   IgnoreImag = ignimag;
585   IgnoreRealAssign = ignreal;
586   IgnoreImagAssign = ignimag;
587   return EmitLoadOfComplex(LHSLV.getAddress(), LHSLV.isVolatileQualified());
588 }
589 
590 ComplexPairTy ComplexExprEmitter::VisitBinAssign(const BinaryOperator *E) {
591   TestAndClearIgnoreReal();
592   TestAndClearIgnoreImag();
593   bool ignreal = TestAndClearIgnoreRealAssign();
594   bool ignimag = TestAndClearIgnoreImagAssign();
595   assert(CGF.getContext().getCanonicalType(E->getLHS()->getType()) ==
596          CGF.getContext().getCanonicalType(E->getRHS()->getType()) &&
597          "Invalid assignment");
598   // Emit the RHS.
599   ComplexPairTy Val = Visit(E->getRHS());
600 
601   // Compute the address to store into.
602   LValue LHS = CGF.EmitLValue(E->getLHS());
603 
604   // Store into it, if simple.
605   if (LHS.isSimple()) {
606     EmitStoreOfComplex(Val, LHS.getAddress(), LHS.isVolatileQualified());
607 
608     // And now return the LHS
609     IgnoreReal = ignreal;
610     IgnoreImag = ignimag;
611     IgnoreRealAssign = ignreal;
612     IgnoreImagAssign = ignimag;
613     return EmitLoadOfComplex(LHS.getAddress(), LHS.isVolatileQualified());
614   }
615 
616   // Otherwise we must have a property setter (no complex vector/bitfields).
617   if (LHS.isPropertyRef())
618     CGF.EmitObjCPropertySet(LHS.getPropertyRefExpr(), RValue::getComplex(Val));
619   else
620     CGF.EmitObjCPropertySet(LHS.getKVCRefExpr(), RValue::getComplex(Val));
621 
622   // There is no reload after a store through a method, but we need to restore
623   // the Ignore* flags.
624   IgnoreReal = ignreal;
625   IgnoreImag = ignimag;
626   IgnoreRealAssign = ignreal;
627   IgnoreImagAssign = ignimag;
628   return Val;
629 }
630 
631 ComplexPairTy ComplexExprEmitter::VisitBinComma(const BinaryOperator *E) {
632   CGF.EmitStmt(E->getLHS());
633   CGF.EnsureInsertPoint();
634   return Visit(E->getRHS());
635 }
636 
637 ComplexPairTy ComplexExprEmitter::
638 VisitConditionalOperator(const ConditionalOperator *E) {
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   llvm::Value *Cond = CGF.EvaluateExprAsBool(E->getCond());
648   Builder.CreateCondBr(Cond, LHSBlock, RHSBlock);
649 
650   CGF.EmitBlock(LHSBlock);
651 
652   // Handle the GNU extension for missing LHS.
653   assert(E->getLHS() && "Must have LHS for complex value");
654 
655   ComplexPairTy LHS = Visit(E->getLHS());
656   LHSBlock = Builder.GetInsertBlock();
657   CGF.EmitBranch(ContBlock);
658 
659   CGF.EmitBlock(RHSBlock);
660 
661   ComplexPairTy RHS = Visit(E->getRHS());
662   RHSBlock = Builder.GetInsertBlock();
663   CGF.EmitBranch(ContBlock);
664 
665   CGF.EmitBlock(ContBlock);
666 
667   // Create a PHI node for the real part.
668   llvm::PHINode *RealPN = Builder.CreatePHI(LHS.first->getType(), "cond.r");
669   RealPN->reserveOperandSpace(2);
670   RealPN->addIncoming(LHS.first, LHSBlock);
671   RealPN->addIncoming(RHS.first, RHSBlock);
672 
673   // Create a PHI node for the imaginary part.
674   llvm::PHINode *ImagPN = Builder.CreatePHI(LHS.first->getType(), "cond.i");
675   ImagPN->reserveOperandSpace(2);
676   ImagPN->addIncoming(LHS.second, LHSBlock);
677   ImagPN->addIncoming(RHS.second, RHSBlock);
678 
679   return ComplexPairTy(RealPN, ImagPN);
680 }
681 
682 ComplexPairTy ComplexExprEmitter::VisitChooseExpr(ChooseExpr *E) {
683   return Visit(E->getChosenSubExpr(CGF.getContext()));
684 }
685 
686 ComplexPairTy ComplexExprEmitter::VisitInitListExpr(InitListExpr *E) {
687     bool Ignore = TestAndClearIgnoreReal();
688     (void)Ignore;
689     assert (Ignore == false && "init list ignored");
690     Ignore = TestAndClearIgnoreImag();
691     (void)Ignore;
692     assert (Ignore == false && "init list ignored");
693   if (E->getNumInits())
694     return Visit(E->getInit(0));
695 
696   // Empty init list intializes to null
697   QualType Ty = E->getType()->getAsComplexType()->getElementType();
698   const llvm::Type* LTy = CGF.ConvertType(Ty);
699   llvm::Value* zeroConstant = CGF.getLLVMContext().getNullValue(LTy);
700   return ComplexPairTy(zeroConstant, zeroConstant);
701 }
702 
703 ComplexPairTy ComplexExprEmitter::VisitVAArgExpr(VAArgExpr *E) {
704   llvm::Value *ArgValue = CGF.EmitVAListRef(E->getSubExpr());
705   llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, E->getType());
706 
707   if (!ArgPtr) {
708     CGF.ErrorUnsupported(E, "complex va_arg expression");
709     const llvm::Type *EltTy =
710       CGF.ConvertType(E->getType()->getAsComplexType()->getElementType());
711     llvm::Value *U = llvm::UndefValue::get(EltTy);
712     return ComplexPairTy(U, U);
713   }
714 
715   // FIXME Volatility.
716   return EmitLoadOfComplex(ArgPtr, false);
717 }
718 
719 //===----------------------------------------------------------------------===//
720 //                         Entry Point into this File
721 //===----------------------------------------------------------------------===//
722 
723 /// EmitComplexExpr - Emit the computation of the specified expression of
724 /// complex type, ignoring the result.
725 ComplexPairTy CodeGenFunction::EmitComplexExpr(const Expr *E, bool IgnoreReal,
726                                                bool IgnoreImag, bool IgnoreRealAssign, bool IgnoreImagAssign) {
727   assert(E && E->getType()->isAnyComplexType() &&
728          "Invalid complex expression to emit");
729 
730   return ComplexExprEmitter(*this, IgnoreReal, IgnoreImag, IgnoreRealAssign,
731                             IgnoreImagAssign)
732     .Visit(const_cast<Expr*>(E));
733 }
734 
735 /// EmitComplexExprIntoAddr - Emit the computation of the specified expression
736 /// of complex type, storing into the specified Value*.
737 void CodeGenFunction::EmitComplexExprIntoAddr(const Expr *E,
738                                               llvm::Value *DestAddr,
739                                               bool DestIsVolatile) {
740   assert(E && E->getType()->isAnyComplexType() &&
741          "Invalid complex expression to emit");
742   ComplexExprEmitter Emitter(*this);
743   ComplexPairTy Val = Emitter.Visit(const_cast<Expr*>(E));
744   Emitter.EmitStoreOfComplex(Val, DestAddr, DestIsVolatile);
745 }
746 
747 /// StoreComplexToAddr - Store a complex number into the specified address.
748 void CodeGenFunction::StoreComplexToAddr(ComplexPairTy V,
749                                          llvm::Value *DestAddr,
750                                          bool DestIsVolatile) {
751   ComplexExprEmitter(*this).EmitStoreOfComplex(V, DestAddr, DestIsVolatile);
752 }
753 
754 /// LoadComplexFromAddr - Load a complex number from the specified address.
755 ComplexPairTy CodeGenFunction::LoadComplexFromAddr(llvm::Value *SrcAddr,
756                                                    bool SrcIsVolatile) {
757   return ComplexExprEmitter(*this).EmitLoadOfComplex(SrcAddr, SrcIsVolatile);
758 }
759