1 //===--- CGExprComplex.cpp - Emit LLVM Code for Complex Exprs -------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This contains code to emit Expr nodes with complex types as LLVM code.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "CodeGenFunction.h"
15 #include "CodeGenModule.h"
16 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/StmtVisitor.h"
18 #include "llvm/Constants.h"
19 #include "llvm/Function.h"
20 #include "llvm/ADT/SmallString.h"
21 using namespace clang;
22 using namespace CodeGen;
23 
24 //===----------------------------------------------------------------------===//
25 //                        Complex Expression Emitter
26 //===----------------------------------------------------------------------===//
27 
28 typedef CodeGenFunction::ComplexPairTy ComplexPairTy;
29 
30 namespace  {
31 class ComplexExprEmitter
32   : public StmtVisitor<ComplexExprEmitter, ComplexPairTy> {
33   CodeGenFunction &CGF;
34   CGBuilderTy &Builder;
35   // True is we should ignore the value of a
36   bool IgnoreReal;
37   bool IgnoreImag;
38 public:
39   ComplexExprEmitter(CodeGenFunction &cgf, bool ir=false, bool ii=false)
40     : CGF(cgf), Builder(CGF.Builder), IgnoreReal(ir), IgnoreImag(ii) {
41   }
42 
43 
44   //===--------------------------------------------------------------------===//
45   //                               Utilities
46   //===--------------------------------------------------------------------===//
47 
48   bool TestAndClearIgnoreReal() {
49     bool I = IgnoreReal;
50     IgnoreReal = false;
51     return I;
52   }
53   bool TestAndClearIgnoreImag() {
54     bool I = IgnoreImag;
55     IgnoreImag = false;
56     return I;
57   }
58 
59   /// EmitLoadOfLValue - Given an expression with complex type that represents a
60   /// value l-value, this method emits the address of the l-value, then loads
61   /// and returns the result.
62   ComplexPairTy EmitLoadOfLValue(const Expr *E) {
63     return EmitLoadOfLValue(CGF.EmitLValue(E));
64   }
65 
66   ComplexPairTy EmitLoadOfLValue(LValue LV) {
67     assert(LV.isSimple() && "complex l-value must be simple");
68     return EmitLoadOfComplex(LV.getAddress(), LV.isVolatileQualified());
69   }
70 
71   /// EmitLoadOfComplex - Given a pointer to a complex value, emit code to load
72   /// the real and imaginary pieces.
73   ComplexPairTy EmitLoadOfComplex(llvm::Value *SrcPtr, bool isVolatile);
74 
75   /// EmitStoreThroughLValue - Given an l-value of complex type, store
76   /// a complex number into it.
77   void EmitStoreThroughLValue(ComplexPairTy Val, LValue LV) {
78     assert(LV.isSimple() && "complex l-value must be simple");
79     return EmitStoreOfComplex(Val, LV.getAddress(), LV.isVolatileQualified());
80   }
81 
82   /// EmitStoreOfComplex - Store the specified real/imag parts into the
83   /// specified value pointer.
84   void EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *ResPtr, bool isVol);
85 
86   /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
87   ComplexPairTy EmitComplexToComplexCast(ComplexPairTy Val, QualType SrcType,
88                                          QualType DestType);
89 
90   //===--------------------------------------------------------------------===//
91   //                            Visitor Methods
92   //===--------------------------------------------------------------------===//
93 
94   ComplexPairTy Visit(Expr *E) {
95     return StmtVisitor<ComplexExprEmitter, ComplexPairTy>::Visit(E);
96   }
97 
98   ComplexPairTy VisitStmt(Stmt *S) {
99     S->dump(CGF.getContext().getSourceManager());
100     llvm_unreachable("Stmt can't have complex result type!");
101   }
102   ComplexPairTy VisitExpr(Expr *S);
103   ComplexPairTy VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr());}
104   ComplexPairTy VisitGenericSelectionExpr(GenericSelectionExpr *GE) {
105     return Visit(GE->getResultExpr());
106   }
107   ComplexPairTy VisitImaginaryLiteral(const ImaginaryLiteral *IL);
108   ComplexPairTy
109   VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *PE) {
110     return Visit(PE->getReplacement());
111   }
112 
113   // l-values.
114   ComplexPairTy VisitDeclRefExpr(const Expr *E) { return EmitLoadOfLValue(E); }
115   ComplexPairTy VisitBlockDeclRefExpr(const Expr *E) { return EmitLoadOfLValue(E); }
116   ComplexPairTy VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
117     return EmitLoadOfLValue(E);
118   }
119   ComplexPairTy VisitObjCMessageExpr(ObjCMessageExpr *E) {
120     return CGF.EmitObjCMessageExpr(E).getComplexVal();
121   }
122   ComplexPairTy VisitArraySubscriptExpr(Expr *E) { return EmitLoadOfLValue(E); }
123   ComplexPairTy VisitMemberExpr(const Expr *E) { return EmitLoadOfLValue(E); }
124   ComplexPairTy VisitOpaqueValueExpr(OpaqueValueExpr *E) {
125     if (E->isGLValue())
126       return EmitLoadOfLValue(CGF.getOpaqueLValueMapping(E));
127     return CGF.getOpaqueRValueMapping(E).getComplexVal();
128   }
129 
130   ComplexPairTy VisitPseudoObjectExpr(PseudoObjectExpr *E) {
131     return CGF.EmitPseudoObjectRValue(E).getComplexVal();
132   }
133 
134   // FIXME: CompoundLiteralExpr
135 
136   ComplexPairTy EmitCast(CastExpr::CastKind CK, Expr *Op, QualType DestTy);
137   ComplexPairTy VisitImplicitCastExpr(ImplicitCastExpr *E) {
138     // Unlike for scalars, we don't have to worry about function->ptr demotion
139     // here.
140     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
141   }
142   ComplexPairTy VisitCastExpr(CastExpr *E) {
143     return EmitCast(E->getCastKind(), E->getSubExpr(), E->getType());
144   }
145   ComplexPairTy VisitCallExpr(const CallExpr *E);
146   ComplexPairTy VisitStmtExpr(const StmtExpr *E);
147 
148   // Operators.
149   ComplexPairTy VisitPrePostIncDec(const UnaryOperator *E,
150                                    bool isInc, bool isPre) {
151     LValue LV = CGF.EmitLValue(E->getSubExpr());
152     return CGF.EmitComplexPrePostIncDec(E, LV, isInc, isPre);
153   }
154   ComplexPairTy VisitUnaryPostDec(const UnaryOperator *E) {
155     return VisitPrePostIncDec(E, false, false);
156   }
157   ComplexPairTy VisitUnaryPostInc(const UnaryOperator *E) {
158     return VisitPrePostIncDec(E, true, false);
159   }
160   ComplexPairTy VisitUnaryPreDec(const UnaryOperator *E) {
161     return VisitPrePostIncDec(E, false, true);
162   }
163   ComplexPairTy VisitUnaryPreInc(const UnaryOperator *E) {
164     return VisitPrePostIncDec(E, true, true);
165   }
166   ComplexPairTy VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); }
167   ComplexPairTy VisitUnaryPlus     (const UnaryOperator *E) {
168     TestAndClearIgnoreReal();
169     TestAndClearIgnoreImag();
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 VisitExprWithCleanups(ExprWithCleanups *E) {
182     CGF.enterFullExpression(E);
183     CodeGenFunction::RunCleanupsScope Scope(CGF);
184     return Visit(E->getSubExpr());
185   }
186   ComplexPairTy VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E) {
187     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
188     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
189     llvm::Constant *Null = llvm::Constant::getNullValue(CGF.ConvertType(Elem));
190     return ComplexPairTy(Null, Null);
191   }
192   ComplexPairTy VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
193     assert(E->getType()->isAnyComplexType() && "Expected complex type!");
194     QualType Elem = E->getType()->getAs<ComplexType>()->getElementType();
195     llvm::Constant *Null =
196                        llvm::Constant::getNullValue(CGF.ConvertType(Elem));
197     return ComplexPairTy(Null, Null);
198   }
199 
200   struct BinOpInfo {
201     ComplexPairTy LHS;
202     ComplexPairTy RHS;
203     QualType Ty;  // Computation Type.
204   };
205 
206   BinOpInfo EmitBinOps(const BinaryOperator *E);
207   LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E,
208                                   ComplexPairTy (ComplexExprEmitter::*Func)
209                                   (const BinOpInfo &),
210                                   ComplexPairTy &Val);
211   ComplexPairTy EmitCompoundAssign(const CompoundAssignOperator *E,
212                                    ComplexPairTy (ComplexExprEmitter::*Func)
213                                    (const BinOpInfo &));
214 
215   ComplexPairTy EmitBinAdd(const BinOpInfo &Op);
216   ComplexPairTy EmitBinSub(const BinOpInfo &Op);
217   ComplexPairTy EmitBinMul(const BinOpInfo &Op);
218   ComplexPairTy EmitBinDiv(const BinOpInfo &Op);
219 
220   ComplexPairTy VisitBinAdd(const BinaryOperator *E) {
221     return EmitBinAdd(EmitBinOps(E));
222   }
223   ComplexPairTy VisitBinSub(const BinaryOperator *E) {
224     return EmitBinSub(EmitBinOps(E));
225   }
226   ComplexPairTy VisitBinMul(const BinaryOperator *E) {
227     return EmitBinMul(EmitBinOps(E));
228   }
229   ComplexPairTy VisitBinDiv(const BinaryOperator *E) {
230     return EmitBinDiv(EmitBinOps(E));
231   }
232 
233   // Compound assignments.
234   ComplexPairTy VisitBinAddAssign(const CompoundAssignOperator *E) {
235     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinAdd);
236   }
237   ComplexPairTy VisitBinSubAssign(const CompoundAssignOperator *E) {
238     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinSub);
239   }
240   ComplexPairTy VisitBinMulAssign(const CompoundAssignOperator *E) {
241     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinMul);
242   }
243   ComplexPairTy VisitBinDivAssign(const CompoundAssignOperator *E) {
244     return EmitCompoundAssign(E, &ComplexExprEmitter::EmitBinDiv);
245   }
246 
247   // GCC rejects rem/and/or/xor for integer complex.
248   // Logical and/or always return int, never complex.
249 
250   // No comparisons produce a complex result.
251 
252   LValue EmitBinAssignLValue(const BinaryOperator *E,
253                              ComplexPairTy &Val);
254   ComplexPairTy VisitBinAssign     (const BinaryOperator *E);
255   ComplexPairTy VisitBinComma      (const BinaryOperator *E);
256 
257 
258   ComplexPairTy
259   VisitAbstractConditionalOperator(const AbstractConditionalOperator *CO);
260   ComplexPairTy VisitChooseExpr(ChooseExpr *CE);
261 
262   ComplexPairTy VisitInitListExpr(InitListExpr *E);
263 
264   ComplexPairTy VisitVAArgExpr(VAArgExpr *E);
265 
266   ComplexPairTy VisitAtomicExpr(AtomicExpr *E) {
267     return CGF.EmitAtomicExpr(E).getComplexVal();
268   }
269 };
270 }  // end anonymous namespace.
271 
272 //===----------------------------------------------------------------------===//
273 //                                Utilities
274 //===----------------------------------------------------------------------===//
275 
276 /// EmitLoadOfComplex - Given an RValue reference for a complex, emit code to
277 /// load the real and imaginary pieces, returning them as Real/Imag.
278 ComplexPairTy ComplexExprEmitter::EmitLoadOfComplex(llvm::Value *SrcPtr,
279                                                     bool isVolatile) {
280   llvm::Value *Real=0, *Imag=0;
281 
282   if (!IgnoreReal || isVolatile) {
283     llvm::Value *RealP = Builder.CreateStructGEP(SrcPtr, 0,
284                                                  SrcPtr->getName() + ".realp");
285     Real = Builder.CreateLoad(RealP, isVolatile, SrcPtr->getName() + ".real");
286   }
287 
288   if (!IgnoreImag || isVolatile) {
289     llvm::Value *ImagP = Builder.CreateStructGEP(SrcPtr, 1,
290                                                  SrcPtr->getName() + ".imagp");
291     Imag = Builder.CreateLoad(ImagP, isVolatile, SrcPtr->getName() + ".imag");
292   }
293   return ComplexPairTy(Real, Imag);
294 }
295 
296 /// EmitStoreOfComplex - Store the specified real/imag parts into the
297 /// specified value pointer.
298 void ComplexExprEmitter::EmitStoreOfComplex(ComplexPairTy Val, llvm::Value *Ptr,
299                                             bool isVolatile) {
300   llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, "real");
301   llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, "imag");
302 
303   Builder.CreateStore(Val.first, RealPtr, isVolatile);
304   Builder.CreateStore(Val.second, ImagPtr, isVolatile);
305 }
306 
307 
308 
309 //===----------------------------------------------------------------------===//
310 //                            Visitor Methods
311 //===----------------------------------------------------------------------===//
312 
313 ComplexPairTy ComplexExprEmitter::VisitExpr(Expr *E) {
314   CGF.ErrorUnsupported(E, "complex expression");
315   llvm::Type *EltTy =
316   CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
317   llvm::Value *U = llvm::UndefValue::get(EltTy);
318   return ComplexPairTy(U, U);
319 }
320 
321 ComplexPairTy ComplexExprEmitter::
322 VisitImaginaryLiteral(const ImaginaryLiteral *IL) {
323   llvm::Value *Imag = CGF.EmitScalarExpr(IL->getSubExpr());
324   return 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   CodeGenFunction::StmtExprEvaluation eval(CGF);
337   return CGF.EmitCompoundStmt(*E->getSubStmt(), true).getComplexVal();
338 }
339 
340 /// EmitComplexToComplexCast - Emit a cast from complex value Val to DestType.
341 ComplexPairTy ComplexExprEmitter::EmitComplexToComplexCast(ComplexPairTy Val,
342                                                            QualType SrcType,
343                                                            QualType DestType) {
344   // Get the src/dest element type.
345   SrcType = SrcType->getAs<ComplexType>()->getElementType();
346   DestType = DestType->getAs<ComplexType>()->getElementType();
347 
348   // C99 6.3.1.6: When a value of complex type is converted to another
349   // complex type, both the real and imaginary parts follow the conversion
350   // rules for the corresponding real types.
351   Val.first = CGF.EmitScalarConversion(Val.first, SrcType, DestType);
352   Val.second = CGF.EmitScalarConversion(Val.second, SrcType, DestType);
353   return Val;
354 }
355 
356 ComplexPairTy ComplexExprEmitter::EmitCast(CastExpr::CastKind CK, Expr *Op,
357                                            QualType DestTy) {
358   switch (CK) {
359   case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!");
360 
361   // Atomic to non-atomic casts may be more than a no-op for some platforms and
362   // for some types.
363   case CK_AtomicToNonAtomic:
364   case CK_NonAtomicToAtomic:
365   case CK_NoOp:
366   case CK_LValueToRValue:
367   case CK_UserDefinedConversion:
368     return Visit(Op);
369 
370   case CK_LValueBitCast: {
371     llvm::Value *V = CGF.EmitLValue(Op).getAddress();
372     V = Builder.CreateBitCast(V,
373                     CGF.ConvertType(CGF.getContext().getPointerType(DestTy)));
374     // FIXME: Are the qualifiers correct here?
375     return EmitLoadOfComplex(V, DestTy.isVolatileQualified());
376   }
377 
378   case CK_BitCast:
379   case CK_BaseToDerived:
380   case CK_DerivedToBase:
381   case CK_UncheckedDerivedToBase:
382   case CK_Dynamic:
383   case CK_ToUnion:
384   case CK_ArrayToPointerDecay:
385   case CK_FunctionToPointerDecay:
386   case CK_NullToPointer:
387   case CK_NullToMemberPointer:
388   case CK_BaseToDerivedMemberPointer:
389   case CK_DerivedToBaseMemberPointer:
390   case CK_MemberPointerToBoolean:
391   case CK_ConstructorConversion:
392   case CK_IntegralToPointer:
393   case CK_PointerToIntegral:
394   case CK_PointerToBoolean:
395   case CK_ToVoid:
396   case CK_VectorSplat:
397   case CK_IntegralCast:
398   case CK_IntegralToBoolean:
399   case CK_IntegralToFloating:
400   case CK_FloatingToIntegral:
401   case CK_FloatingToBoolean:
402   case CK_FloatingCast:
403   case CK_CPointerToObjCPointerCast:
404   case CK_BlockPointerToObjCPointerCast:
405   case CK_AnyPointerToBlockPointerCast:
406   case CK_ObjCObjectLValueCast:
407   case CK_FloatingComplexToReal:
408   case CK_FloatingComplexToBoolean:
409   case CK_IntegralComplexToReal:
410   case CK_IntegralComplexToBoolean:
411   case CK_ARCProduceObject:
412   case CK_ARCConsumeObject:
413   case CK_ARCReclaimReturnedObject:
414   case CK_ARCExtendBlockObject:
415     llvm_unreachable("invalid cast kind for complex value");
416 
417   case CK_FloatingRealToComplex:
418   case CK_IntegralRealToComplex: {
419     llvm::Value *Elt = CGF.EmitScalarExpr(Op);
420 
421     // Convert the input element to the element type of the complex.
422     DestTy = DestTy->getAs<ComplexType>()->getElementType();
423     Elt = CGF.EmitScalarConversion(Elt, Op->getType(), DestTy);
424 
425     // Return (realval, 0).
426     return ComplexPairTy(Elt, llvm::Constant::getNullValue(Elt->getType()));
427   }
428 
429   case CK_FloatingComplexCast:
430   case CK_FloatingComplexToIntegralComplex:
431   case CK_IntegralComplexCast:
432   case CK_IntegralComplexToFloatingComplex:
433     return EmitComplexToComplexCast(Visit(Op), Op->getType(), DestTy);
434   }
435 
436   llvm_unreachable("unknown cast resulting in complex value");
437 }
438 
439 ComplexPairTy ComplexExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
440   TestAndClearIgnoreReal();
441   TestAndClearIgnoreImag();
442   ComplexPairTy Op = Visit(E->getSubExpr());
443 
444   llvm::Value *ResR, *ResI;
445   if (Op.first->getType()->isFloatingPointTy()) {
446     ResR = Builder.CreateFNeg(Op.first,  "neg.r");
447     ResI = Builder.CreateFNeg(Op.second, "neg.i");
448   } else {
449     ResR = Builder.CreateNeg(Op.first,  "neg.r");
450     ResI = Builder.CreateNeg(Op.second, "neg.i");
451   }
452   return ComplexPairTy(ResR, ResI);
453 }
454 
455 ComplexPairTy ComplexExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
456   TestAndClearIgnoreReal();
457   TestAndClearIgnoreImag();
458   // ~(a+ib) = a + i*-b
459   ComplexPairTy Op = Visit(E->getSubExpr());
460   llvm::Value *ResI;
461   if (Op.second->getType()->isFloatingPointTy())
462     ResI = Builder.CreateFNeg(Op.second, "conj.i");
463   else
464     ResI = Builder.CreateNeg(Op.second, "conj.i");
465 
466   return ComplexPairTy(Op.first, ResI);
467 }
468 
469 ComplexPairTy ComplexExprEmitter::EmitBinAdd(const BinOpInfo &Op) {
470   llvm::Value *ResR, *ResI;
471 
472   if (Op.LHS.first->getType()->isFloatingPointTy()) {
473     ResR = Builder.CreateFAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
474     ResI = Builder.CreateFAdd(Op.LHS.second, Op.RHS.second, "add.i");
475   } else {
476     ResR = Builder.CreateAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
477     ResI = Builder.CreateAdd(Op.LHS.second, Op.RHS.second, "add.i");
478   }
479   return ComplexPairTy(ResR, ResI);
480 }
481 
482 ComplexPairTy ComplexExprEmitter::EmitBinSub(const BinOpInfo &Op) {
483   llvm::Value *ResR, *ResI;
484   if (Op.LHS.first->getType()->isFloatingPointTy()) {
485     ResR = Builder.CreateFSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
486     ResI = Builder.CreateFSub(Op.LHS.second, Op.RHS.second, "sub.i");
487   } else {
488     ResR = Builder.CreateSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
489     ResI = Builder.CreateSub(Op.LHS.second, Op.RHS.second, "sub.i");
490   }
491   return ComplexPairTy(ResR, ResI);
492 }
493 
494 
495 ComplexPairTy ComplexExprEmitter::EmitBinMul(const BinOpInfo &Op) {
496   using llvm::Value;
497   Value *ResR, *ResI;
498 
499   if (Op.LHS.first->getType()->isFloatingPointTy()) {
500     Value *ResRl = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul.rl");
501     Value *ResRr = Builder.CreateFMul(Op.LHS.second, Op.RHS.second,"mul.rr");
502     ResR  = Builder.CreateFSub(ResRl, ResRr, "mul.r");
503 
504     Value *ResIl = Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul.il");
505     Value *ResIr = Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul.ir");
506     ResI  = Builder.CreateFAdd(ResIl, ResIr, "mul.i");
507   } else {
508     Value *ResRl = Builder.CreateMul(Op.LHS.first, Op.RHS.first, "mul.rl");
509     Value *ResRr = Builder.CreateMul(Op.LHS.second, Op.RHS.second,"mul.rr");
510     ResR  = Builder.CreateSub(ResRl, ResRr, "mul.r");
511 
512     Value *ResIl = Builder.CreateMul(Op.LHS.second, Op.RHS.first, "mul.il");
513     Value *ResIr = Builder.CreateMul(Op.LHS.first, Op.RHS.second, "mul.ir");
514     ResI  = Builder.CreateAdd(ResIl, ResIr, "mul.i");
515   }
516   return ComplexPairTy(ResR, ResI);
517 }
518 
519 ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
520   llvm::Value *LHSr = Op.LHS.first, *LHSi = Op.LHS.second;
521   llvm::Value *RHSr = Op.RHS.first, *RHSi = Op.RHS.second;
522 
523 
524   llvm::Value *DSTr, *DSTi;
525   if (Op.LHS.first->getType()->isFloatingPointTy()) {
526     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
527     llvm::Value *Tmp1 = Builder.CreateFMul(LHSr, RHSr); // a*c
528     llvm::Value *Tmp2 = Builder.CreateFMul(LHSi, RHSi); // b*d
529     llvm::Value *Tmp3 = Builder.CreateFAdd(Tmp1, Tmp2); // ac+bd
530 
531     llvm::Value *Tmp4 = Builder.CreateFMul(RHSr, RHSr); // c*c
532     llvm::Value *Tmp5 = Builder.CreateFMul(RHSi, RHSi); // d*d
533     llvm::Value *Tmp6 = Builder.CreateFAdd(Tmp4, Tmp5); // cc+dd
534 
535     llvm::Value *Tmp7 = Builder.CreateFMul(LHSi, RHSr); // b*c
536     llvm::Value *Tmp8 = Builder.CreateFMul(LHSr, RHSi); // a*d
537     llvm::Value *Tmp9 = Builder.CreateFSub(Tmp7, Tmp8); // bc-ad
538 
539     DSTr = Builder.CreateFDiv(Tmp3, Tmp6);
540     DSTi = Builder.CreateFDiv(Tmp9, Tmp6);
541   } else {
542     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
543     llvm::Value *Tmp1 = Builder.CreateMul(LHSr, RHSr); // a*c
544     llvm::Value *Tmp2 = Builder.CreateMul(LHSi, RHSi); // b*d
545     llvm::Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2); // ac+bd
546 
547     llvm::Value *Tmp4 = Builder.CreateMul(RHSr, RHSr); // c*c
548     llvm::Value *Tmp5 = Builder.CreateMul(RHSi, RHSi); // d*d
549     llvm::Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5); // cc+dd
550 
551     llvm::Value *Tmp7 = Builder.CreateMul(LHSi, RHSr); // b*c
552     llvm::Value *Tmp8 = Builder.CreateMul(LHSr, RHSi); // a*d
553     llvm::Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8); // bc-ad
554 
555     if (Op.Ty->getAs<ComplexType>()->getElementType()->isUnsignedIntegerType()) {
556       DSTr = Builder.CreateUDiv(Tmp3, Tmp6);
557       DSTi = Builder.CreateUDiv(Tmp9, Tmp6);
558     } else {
559       DSTr = Builder.CreateSDiv(Tmp3, Tmp6);
560       DSTi = Builder.CreateSDiv(Tmp9, Tmp6);
561     }
562   }
563 
564   return ComplexPairTy(DSTr, DSTi);
565 }
566 
567 ComplexExprEmitter::BinOpInfo
568 ComplexExprEmitter::EmitBinOps(const BinaryOperator *E) {
569   TestAndClearIgnoreReal();
570   TestAndClearIgnoreImag();
571   BinOpInfo Ops;
572   Ops.LHS = Visit(E->getLHS());
573   Ops.RHS = Visit(E->getRHS());
574   Ops.Ty = E->getType();
575   return Ops;
576 }
577 
578 
579 LValue ComplexExprEmitter::
580 EmitCompoundAssignLValue(const CompoundAssignOperator *E,
581           ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&),
582                          ComplexPairTy &Val) {
583   TestAndClearIgnoreReal();
584   TestAndClearIgnoreImag();
585   QualType LHSTy = E->getLHS()->getType();
586 
587   BinOpInfo OpInfo;
588 
589   // Load the RHS and LHS operands.
590   // __block variables need to have the rhs evaluated first, plus this should
591   // improve codegen a little.
592   OpInfo.Ty = E->getComputationResultType();
593 
594   // The RHS should have been converted to the computation type.
595   assert(OpInfo.Ty->isAnyComplexType());
596   assert(CGF.getContext().hasSameUnqualifiedType(OpInfo.Ty,
597                                                  E->getRHS()->getType()));
598   OpInfo.RHS = Visit(E->getRHS());
599 
600   LValue LHS = CGF.EmitLValue(E->getLHS());
601 
602   // Load from the l-value.
603   ComplexPairTy LHSComplexPair = EmitLoadOfLValue(LHS);
604 
605   OpInfo.LHS = EmitComplexToComplexCast(LHSComplexPair, LHSTy, OpInfo.Ty);
606 
607   // Expand the binary operator.
608   ComplexPairTy Result = (this->*Func)(OpInfo);
609 
610   // Truncate the result back to the LHS type.
611   Result = EmitComplexToComplexCast(Result, OpInfo.Ty, LHSTy);
612   Val = Result;
613 
614   // Store the result value into the LHS lvalue.
615   EmitStoreThroughLValue(Result, LHS);
616 
617   return LHS;
618 }
619 
620 // Compound assignments.
621 ComplexPairTy ComplexExprEmitter::
622 EmitCompoundAssign(const CompoundAssignOperator *E,
623                    ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&)){
624   ComplexPairTy Val;
625   LValue LV = EmitCompoundAssignLValue(E, Func, Val);
626 
627   // The result of an assignment in C is the assigned r-value.
628   if (!CGF.getContext().getLangOptions().CPlusPlus)
629     return Val;
630 
631   // If the lvalue is non-volatile, return the computed value of the assignment.
632   if (!LV.isVolatileQualified())
633     return Val;
634 
635   return EmitLoadOfComplex(LV.getAddress(), LV.isVolatileQualified());
636 }
637 
638 LValue ComplexExprEmitter::EmitBinAssignLValue(const BinaryOperator *E,
639                                                ComplexPairTy &Val) {
640   assert(CGF.getContext().hasSameUnqualifiedType(E->getLHS()->getType(),
641                                                  E->getRHS()->getType()) &&
642          "Invalid assignment");
643   TestAndClearIgnoreReal();
644   TestAndClearIgnoreImag();
645 
646   // Emit the RHS.  __block variables need the RHS evaluated first.
647   Val = Visit(E->getRHS());
648 
649   // Compute the address to store into.
650   LValue LHS = CGF.EmitLValue(E->getLHS());
651 
652   // Store the result value into the LHS lvalue.
653   EmitStoreThroughLValue(Val, LHS);
654 
655   return LHS;
656 }
657 
658 ComplexPairTy ComplexExprEmitter::VisitBinAssign(const BinaryOperator *E) {
659   ComplexPairTy Val;
660   LValue LV = EmitBinAssignLValue(E, Val);
661 
662   // The result of an assignment in C is the assigned r-value.
663   if (!CGF.getContext().getLangOptions().CPlusPlus)
664     return Val;
665 
666   // If the lvalue is non-volatile, return the computed value of the assignment.
667   if (!LV.isVolatileQualified())
668     return Val;
669 
670   return EmitLoadOfComplex(LV.getAddress(), LV.isVolatileQualified());
671 }
672 
673 ComplexPairTy ComplexExprEmitter::VisitBinComma(const BinaryOperator *E) {
674   CGF.EmitIgnoredExpr(E->getLHS());
675   return Visit(E->getRHS());
676 }
677 
678 ComplexPairTy ComplexExprEmitter::
679 VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) {
680   TestAndClearIgnoreReal();
681   TestAndClearIgnoreImag();
682   llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
683   llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
684   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
685 
686   // Bind the common expression if necessary.
687   CodeGenFunction::OpaqueValueMapping binding(CGF, E);
688 
689   CodeGenFunction::ConditionalEvaluation eval(CGF);
690   CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock);
691 
692   eval.begin(CGF);
693   CGF.EmitBlock(LHSBlock);
694   ComplexPairTy LHS = Visit(E->getTrueExpr());
695   LHSBlock = Builder.GetInsertBlock();
696   CGF.EmitBranch(ContBlock);
697   eval.end(CGF);
698 
699   eval.begin(CGF);
700   CGF.EmitBlock(RHSBlock);
701   ComplexPairTy RHS = Visit(E->getFalseExpr());
702   RHSBlock = Builder.GetInsertBlock();
703   CGF.EmitBlock(ContBlock);
704   eval.end(CGF);
705 
706   // Create a PHI node for the real part.
707   llvm::PHINode *RealPN = Builder.CreatePHI(LHS.first->getType(), 2, "cond.r");
708   RealPN->addIncoming(LHS.first, LHSBlock);
709   RealPN->addIncoming(RHS.first, RHSBlock);
710 
711   // Create a PHI node for the imaginary part.
712   llvm::PHINode *ImagPN = Builder.CreatePHI(LHS.first->getType(), 2, "cond.i");
713   ImagPN->addIncoming(LHS.second, LHSBlock);
714   ImagPN->addIncoming(RHS.second, RHSBlock);
715 
716   return ComplexPairTy(RealPN, ImagPN);
717 }
718 
719 ComplexPairTy ComplexExprEmitter::VisitChooseExpr(ChooseExpr *E) {
720   return Visit(E->getChosenSubExpr(CGF.getContext()));
721 }
722 
723 ComplexPairTy ComplexExprEmitter::VisitInitListExpr(InitListExpr *E) {
724     bool Ignore = TestAndClearIgnoreReal();
725     (void)Ignore;
726     assert (Ignore == false && "init list ignored");
727     Ignore = TestAndClearIgnoreImag();
728     (void)Ignore;
729     assert (Ignore == false && "init list ignored");
730 
731   if (E->getNumInits() == 2) {
732     llvm::Value *Real = CGF.EmitScalarExpr(E->getInit(0));
733     llvm::Value *Imag = CGF.EmitScalarExpr(E->getInit(1));
734     return ComplexPairTy(Real, Imag);
735   } else if (E->getNumInits() == 1) {
736     return Visit(E->getInit(0));
737   }
738 
739   // Empty init list intializes to null
740   assert(E->getNumInits() == 0 && "Unexpected number of inits");
741   QualType Ty = E->getType()->getAs<ComplexType>()->getElementType();
742   llvm::Type* LTy = CGF.ConvertType(Ty);
743   llvm::Value* zeroConstant = llvm::Constant::getNullValue(LTy);
744   return ComplexPairTy(zeroConstant, zeroConstant);
745 }
746 
747 ComplexPairTy ComplexExprEmitter::VisitVAArgExpr(VAArgExpr *E) {
748   llvm::Value *ArgValue = CGF.EmitVAListRef(E->getSubExpr());
749   llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, E->getType());
750 
751   if (!ArgPtr) {
752     CGF.ErrorUnsupported(E, "complex va_arg expression");
753     llvm::Type *EltTy =
754       CGF.ConvertType(E->getType()->getAs<ComplexType>()->getElementType());
755     llvm::Value *U = llvm::UndefValue::get(EltTy);
756     return ComplexPairTy(U, U);
757   }
758 
759   // FIXME Volatility.
760   return EmitLoadOfComplex(ArgPtr, false);
761 }
762 
763 //===----------------------------------------------------------------------===//
764 //                         Entry Point into this File
765 //===----------------------------------------------------------------------===//
766 
767 /// EmitComplexExpr - Emit the computation of the specified expression of
768 /// complex type, ignoring the result.
769 ComplexPairTy CodeGenFunction::EmitComplexExpr(const Expr *E, bool IgnoreReal,
770                                                bool IgnoreImag) {
771   assert(E && E->getType()->isAnyComplexType() &&
772          "Invalid complex expression to emit");
773 
774   return ComplexExprEmitter(*this, IgnoreReal, IgnoreImag)
775     .Visit(const_cast<Expr*>(E));
776 }
777 
778 /// EmitComplexExprIntoAddr - Emit the computation of the specified expression
779 /// of complex type, storing into the specified Value*.
780 void CodeGenFunction::EmitComplexExprIntoAddr(const Expr *E,
781                                               llvm::Value *DestAddr,
782                                               bool DestIsVolatile) {
783   assert(E && E->getType()->isAnyComplexType() &&
784          "Invalid complex expression to emit");
785   ComplexExprEmitter Emitter(*this);
786   ComplexPairTy Val = Emitter.Visit(const_cast<Expr*>(E));
787   Emitter.EmitStoreOfComplex(Val, DestAddr, DestIsVolatile);
788 }
789 
790 /// StoreComplexToAddr - Store a complex number into the specified address.
791 void CodeGenFunction::StoreComplexToAddr(ComplexPairTy V,
792                                          llvm::Value *DestAddr,
793                                          bool DestIsVolatile) {
794   ComplexExprEmitter(*this).EmitStoreOfComplex(V, DestAddr, DestIsVolatile);
795 }
796 
797 /// LoadComplexFromAddr - Load a complex number from the specified address.
798 ComplexPairTy CodeGenFunction::LoadComplexFromAddr(llvm::Value *SrcAddr,
799                                                    bool SrcIsVolatile) {
800   return ComplexExprEmitter(*this).EmitLoadOfComplex(SrcAddr, SrcIsVolatile);
801 }
802 
803 LValue CodeGenFunction::EmitComplexAssignmentLValue(const BinaryOperator *E) {
804   assert(E->getOpcode() == BO_Assign);
805   ComplexPairTy Val; // ignored
806   return ComplexExprEmitter(*this).EmitBinAssignLValue(E, Val);
807 }
808 
809 LValue CodeGenFunction::
810 EmitComplexCompoundAssignmentLValue(const CompoundAssignOperator *E) {
811   ComplexPairTy(ComplexExprEmitter::*Op)(const ComplexExprEmitter::BinOpInfo &);
812   switch (E->getOpcode()) {
813   case BO_MulAssign: Op = &ComplexExprEmitter::EmitBinMul; break;
814   case BO_DivAssign: Op = &ComplexExprEmitter::EmitBinDiv; break;
815   case BO_SubAssign: Op = &ComplexExprEmitter::EmitBinSub; break;
816   case BO_AddAssign: Op = &ComplexExprEmitter::EmitBinAdd; break;
817 
818   default:
819     llvm_unreachable("unexpected complex compound assignment");
820     Op = 0;
821   }
822 
823   ComplexPairTy Val; // ignored
824   return ComplexExprEmitter(*this).EmitCompoundAssignLValue(E, Op, Val);
825 }
826