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   llvm::LLVMContext &VMContext = CGF.getLLVMContext();
371 
372   LValue LV = CGF.EmitLValue(E->getSubExpr());
373   ComplexPairTy InVal = EmitLoadOfComplex(LV.getAddress(),
374                                           LV.isVolatileQualified());
375 
376   llvm::Value *NextVal;
377   if (isa<llvm::IntegerType>(InVal.first->getType())) {
378     uint64_t AmountVal = isInc ? 1 : -1;
379     NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
380 
381     // Add the inc/dec to the real part.
382     NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
383 
384   } else {
385     QualType ElemTy = E->getType()->getAsComplexType()->getElementType();
386     llvm::APFloat FVal(CGF.getContext().getFloatTypeSemantics(ElemTy), 1);
387     if (!isInc)
388       FVal.changeSign();
389     NextVal = VMContext.getConstantFP(FVal);
390 
391     // Add the inc/dec to the real part.
392     NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
393   }
394 
395   ComplexPairTy IncVal(NextVal, InVal.second);
396 
397   // Store the updated result through the lvalue.
398   EmitStoreOfComplex(IncVal, LV.getAddress(), LV.isVolatileQualified());
399 
400   // If this is a postinc, return the value read from memory, otherwise use the
401   // updated value.
402   return isPre ? IncVal : InVal;
403 }
404 
405 ComplexPairTy ComplexExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
406   TestAndClearIgnoreReal();
407   TestAndClearIgnoreImag();
408   TestAndClearIgnoreRealAssign();
409   TestAndClearIgnoreImagAssign();
410   ComplexPairTy Op = Visit(E->getSubExpr());
411 
412   llvm::Value *ResR, *ResI;
413   if (Op.first->getType()->isFloatingPoint()) {
414     ResR = Builder.CreateFNeg(Op.first,  "neg.r");
415     ResI = Builder.CreateFNeg(Op.second, "neg.i");
416   } else {
417     ResR = Builder.CreateNeg(Op.first,  "neg.r");
418     ResI = Builder.CreateNeg(Op.second, "neg.i");
419   }
420   return ComplexPairTy(ResR, ResI);
421 }
422 
423 ComplexPairTy ComplexExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
424   TestAndClearIgnoreReal();
425   TestAndClearIgnoreImag();
426   TestAndClearIgnoreRealAssign();
427   TestAndClearIgnoreImagAssign();
428   // ~(a+ib) = a + i*-b
429   ComplexPairTy Op = Visit(E->getSubExpr());
430   llvm::Value *ResI;
431   if (Op.second->getType()->isFloatingPoint())
432     ResI = Builder.CreateFNeg(Op.second, "conj.i");
433   else
434     ResI = Builder.CreateNeg(Op.second, "conj.i");
435 
436   return ComplexPairTy(Op.first, ResI);
437 }
438 
439 ComplexPairTy ComplexExprEmitter::EmitBinAdd(const BinOpInfo &Op) {
440   llvm::Value *ResR, *ResI;
441 
442   if (Op.LHS.first->getType()->isFloatingPoint()) {
443     ResR = Builder.CreateFAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
444     ResI = Builder.CreateFAdd(Op.LHS.second, Op.RHS.second, "add.i");
445   } else {
446     ResR = Builder.CreateAdd(Op.LHS.first,  Op.RHS.first,  "add.r");
447     ResI = Builder.CreateAdd(Op.LHS.second, Op.RHS.second, "add.i");
448   }
449   return ComplexPairTy(ResR, ResI);
450 }
451 
452 ComplexPairTy ComplexExprEmitter::EmitBinSub(const BinOpInfo &Op) {
453   llvm::Value *ResR, *ResI;
454   if (Op.LHS.first->getType()->isFloatingPoint()) {
455     ResR = Builder.CreateFSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
456     ResI = Builder.CreateFSub(Op.LHS.second, Op.RHS.second, "sub.i");
457   } else {
458     ResR = Builder.CreateSub(Op.LHS.first,  Op.RHS.first,  "sub.r");
459     ResI = Builder.CreateSub(Op.LHS.second, Op.RHS.second, "sub.i");
460   }
461   return ComplexPairTy(ResR, ResI);
462 }
463 
464 
465 ComplexPairTy ComplexExprEmitter::EmitBinMul(const BinOpInfo &Op) {
466   using llvm::Value;
467   Value *ResR, *ResI;
468 
469   if (Op.LHS.first->getType()->isFloatingPoint()) {
470     Value *ResRl = Builder.CreateFMul(Op.LHS.first, Op.RHS.first, "mul.rl");
471     Value *ResRr = Builder.CreateFMul(Op.LHS.second, Op.RHS.second,"mul.rr");
472     ResR  = Builder.CreateFSub(ResRl, ResRr, "mul.r");
473 
474     Value *ResIl = Builder.CreateFMul(Op.LHS.second, Op.RHS.first, "mul.il");
475     Value *ResIr = Builder.CreateFMul(Op.LHS.first, Op.RHS.second, "mul.ir");
476     ResI  = Builder.CreateFAdd(ResIl, ResIr, "mul.i");
477   } else {
478     Value *ResRl = Builder.CreateMul(Op.LHS.first, Op.RHS.first, "mul.rl");
479     Value *ResRr = Builder.CreateMul(Op.LHS.second, Op.RHS.second,"mul.rr");
480     ResR  = Builder.CreateSub(ResRl, ResRr, "mul.r");
481 
482     Value *ResIl = Builder.CreateMul(Op.LHS.second, Op.RHS.first, "mul.il");
483     Value *ResIr = Builder.CreateMul(Op.LHS.first, Op.RHS.second, "mul.ir");
484     ResI  = Builder.CreateAdd(ResIl, ResIr, "mul.i");
485   }
486   return ComplexPairTy(ResR, ResI);
487 }
488 
489 ComplexPairTy ComplexExprEmitter::EmitBinDiv(const BinOpInfo &Op) {
490   llvm::Value *LHSr = Op.LHS.first, *LHSi = Op.LHS.second;
491   llvm::Value *RHSr = Op.RHS.first, *RHSi = Op.RHS.second;
492 
493 
494   llvm::Value *DSTr, *DSTi;
495   if (Op.LHS.first->getType()->isFloatingPoint()) {
496     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
497     llvm::Value *Tmp1 = Builder.CreateFMul(LHSr, RHSr, "tmp"); // a*c
498     llvm::Value *Tmp2 = Builder.CreateFMul(LHSi, RHSi, "tmp"); // b*d
499     llvm::Value *Tmp3 = Builder.CreateFAdd(Tmp1, Tmp2, "tmp"); // ac+bd
500 
501     llvm::Value *Tmp4 = Builder.CreateFMul(RHSr, RHSr, "tmp"); // c*c
502     llvm::Value *Tmp5 = Builder.CreateFMul(RHSi, RHSi, "tmp"); // d*d
503     llvm::Value *Tmp6 = Builder.CreateFAdd(Tmp4, Tmp5, "tmp"); // cc+dd
504 
505     llvm::Value *Tmp7 = Builder.CreateFMul(LHSi, RHSr, "tmp"); // b*c
506     llvm::Value *Tmp8 = Builder.CreateFMul(LHSr, RHSi, "tmp"); // a*d
507     llvm::Value *Tmp9 = Builder.CreateFSub(Tmp7, Tmp8, "tmp"); // bc-ad
508 
509     DSTr = Builder.CreateFDiv(Tmp3, Tmp6, "tmp");
510     DSTi = Builder.CreateFDiv(Tmp9, Tmp6, "tmp");
511   } else {
512     // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
513     llvm::Value *Tmp1 = Builder.CreateMul(LHSr, RHSr, "tmp"); // a*c
514     llvm::Value *Tmp2 = Builder.CreateMul(LHSi, RHSi, "tmp"); // b*d
515     llvm::Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2, "tmp"); // ac+bd
516 
517     llvm::Value *Tmp4 = Builder.CreateMul(RHSr, RHSr, "tmp"); // c*c
518     llvm::Value *Tmp5 = Builder.CreateMul(RHSi, RHSi, "tmp"); // d*d
519     llvm::Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5, "tmp"); // cc+dd
520 
521     llvm::Value *Tmp7 = Builder.CreateMul(LHSi, RHSr, "tmp"); // b*c
522     llvm::Value *Tmp8 = Builder.CreateMul(LHSr, RHSi, "tmp"); // a*d
523     llvm::Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8, "tmp"); // bc-ad
524 
525     if (Op.Ty->getAsComplexType()->getElementType()->isUnsignedIntegerType()) {
526       DSTr = Builder.CreateUDiv(Tmp3, Tmp6, "tmp");
527       DSTi = Builder.CreateUDiv(Tmp9, Tmp6, "tmp");
528     } else {
529       DSTr = Builder.CreateSDiv(Tmp3, Tmp6, "tmp");
530       DSTi = Builder.CreateSDiv(Tmp9, Tmp6, "tmp");
531     }
532   }
533 
534   return ComplexPairTy(DSTr, DSTi);
535 }
536 
537 ComplexExprEmitter::BinOpInfo
538 ComplexExprEmitter::EmitBinOps(const BinaryOperator *E) {
539   TestAndClearIgnoreReal();
540   TestAndClearIgnoreImag();
541   TestAndClearIgnoreRealAssign();
542   TestAndClearIgnoreImagAssign();
543   BinOpInfo Ops;
544   Ops.LHS = Visit(E->getLHS());
545   Ops.RHS = Visit(E->getRHS());
546   Ops.Ty = E->getType();
547   return Ops;
548 }
549 
550 
551 // Compound assignments.
552 ComplexPairTy ComplexExprEmitter::
553 EmitCompoundAssign(const CompoundAssignOperator *E,
554                    ComplexPairTy (ComplexExprEmitter::*Func)(const BinOpInfo&)){
555   TestAndClearIgnoreReal();
556   TestAndClearIgnoreImag();
557   bool ignreal = TestAndClearIgnoreRealAssign();
558   bool ignimag = TestAndClearIgnoreImagAssign();
559   QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType();
560 
561   BinOpInfo OpInfo;
562 
563   // Load the RHS and LHS operands.
564   // __block variables need to have the rhs evaluated first, plus this should
565   // improve codegen a little.  It is possible for the RHS to be complex or
566   // scalar.
567   OpInfo.Ty = E->getComputationResultType();
568   OpInfo.RHS = EmitCast(E->getRHS(), OpInfo.Ty);
569 
570   LValue LHSLV = CGF.EmitLValue(E->getLHS());
571 
572 
573   // We know the LHS is a complex lvalue.
574   OpInfo.LHS=EmitLoadOfComplex(LHSLV.getAddress(),LHSLV.isVolatileQualified());
575   OpInfo.LHS=EmitComplexToComplexCast(OpInfo.LHS, LHSTy, OpInfo.Ty);
576 
577   // Expand the binary operator.
578   ComplexPairTy Result = (this->*Func)(OpInfo);
579 
580   // Truncate the result back to the LHS type.
581   Result = EmitComplexToComplexCast(Result, OpInfo.Ty, LHSTy);
582 
583   // Store the result value into the LHS lvalue.
584   EmitStoreOfComplex(Result, LHSLV.getAddress(), LHSLV.isVolatileQualified());
585   // And now return the LHS
586   IgnoreReal = ignreal;
587   IgnoreImag = ignimag;
588   IgnoreRealAssign = ignreal;
589   IgnoreImagAssign = ignimag;
590   return EmitLoadOfComplex(LHSLV.getAddress(), LHSLV.isVolatileQualified());
591 }
592 
593 ComplexPairTy ComplexExprEmitter::VisitBinAssign(const BinaryOperator *E) {
594   TestAndClearIgnoreReal();
595   TestAndClearIgnoreImag();
596   bool ignreal = TestAndClearIgnoreRealAssign();
597   bool ignimag = TestAndClearIgnoreImagAssign();
598   assert(CGF.getContext().getCanonicalType(E->getLHS()->getType()) ==
599          CGF.getContext().getCanonicalType(E->getRHS()->getType()) &&
600          "Invalid assignment");
601   // Emit the RHS.
602   ComplexPairTy Val = Visit(E->getRHS());
603 
604   // Compute the address to store into.
605   LValue LHS = CGF.EmitLValue(E->getLHS());
606 
607   // Store into it, if simple.
608   if (LHS.isSimple()) {
609     EmitStoreOfComplex(Val, LHS.getAddress(), LHS.isVolatileQualified());
610 
611     // And now return the LHS
612     IgnoreReal = ignreal;
613     IgnoreImag = ignimag;
614     IgnoreRealAssign = ignreal;
615     IgnoreImagAssign = ignimag;
616     return EmitLoadOfComplex(LHS.getAddress(), LHS.isVolatileQualified());
617   }
618 
619   // Otherwise we must have a property setter (no complex vector/bitfields).
620   if (LHS.isPropertyRef())
621     CGF.EmitObjCPropertySet(LHS.getPropertyRefExpr(), RValue::getComplex(Val));
622   else
623     CGF.EmitObjCPropertySet(LHS.getKVCRefExpr(), RValue::getComplex(Val));
624 
625   // There is no reload after a store through a method, but we need to restore
626   // the Ignore* flags.
627   IgnoreReal = ignreal;
628   IgnoreImag = ignimag;
629   IgnoreRealAssign = ignreal;
630   IgnoreImagAssign = ignimag;
631   return Val;
632 }
633 
634 ComplexPairTy ComplexExprEmitter::VisitBinComma(const BinaryOperator *E) {
635   CGF.EmitStmt(E->getLHS());
636   CGF.EnsureInsertPoint();
637   return Visit(E->getRHS());
638 }
639 
640 ComplexPairTy ComplexExprEmitter::
641 VisitConditionalOperator(const ConditionalOperator *E) {
642   TestAndClearIgnoreReal();
643   TestAndClearIgnoreImag();
644   TestAndClearIgnoreRealAssign();
645   TestAndClearIgnoreImagAssign();
646   llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
647   llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
648   llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
649 
650   llvm::Value *Cond = CGF.EvaluateExprAsBool(E->getCond());
651   Builder.CreateCondBr(Cond, LHSBlock, RHSBlock);
652 
653   CGF.EmitBlock(LHSBlock);
654 
655   // Handle the GNU extension for missing LHS.
656   assert(E->getLHS() && "Must have LHS for complex value");
657 
658   ComplexPairTy LHS = Visit(E->getLHS());
659   LHSBlock = Builder.GetInsertBlock();
660   CGF.EmitBranch(ContBlock);
661 
662   CGF.EmitBlock(RHSBlock);
663 
664   ComplexPairTy RHS = Visit(E->getRHS());
665   RHSBlock = Builder.GetInsertBlock();
666   CGF.EmitBranch(ContBlock);
667 
668   CGF.EmitBlock(ContBlock);
669 
670   // Create a PHI node for the real part.
671   llvm::PHINode *RealPN = Builder.CreatePHI(LHS.first->getType(), "cond.r");
672   RealPN->reserveOperandSpace(2);
673   RealPN->addIncoming(LHS.first, LHSBlock);
674   RealPN->addIncoming(RHS.first, RHSBlock);
675 
676   // Create a PHI node for the imaginary part.
677   llvm::PHINode *ImagPN = Builder.CreatePHI(LHS.first->getType(), "cond.i");
678   ImagPN->reserveOperandSpace(2);
679   ImagPN->addIncoming(LHS.second, LHSBlock);
680   ImagPN->addIncoming(RHS.second, RHSBlock);
681 
682   return ComplexPairTy(RealPN, ImagPN);
683 }
684 
685 ComplexPairTy ComplexExprEmitter::VisitChooseExpr(ChooseExpr *E) {
686   return Visit(E->getChosenSubExpr(CGF.getContext()));
687 }
688 
689 ComplexPairTy ComplexExprEmitter::VisitInitListExpr(InitListExpr *E) {
690     bool Ignore = TestAndClearIgnoreReal();
691     (void)Ignore;
692     assert (Ignore == false && "init list ignored");
693     Ignore = TestAndClearIgnoreImag();
694     (void)Ignore;
695     assert (Ignore == false && "init list ignored");
696   if (E->getNumInits())
697     return Visit(E->getInit(0));
698 
699   // Empty init list intializes to null
700   QualType Ty = E->getType()->getAsComplexType()->getElementType();
701   const llvm::Type* LTy = CGF.ConvertType(Ty);
702   llvm::Value* zeroConstant = CGF.getLLVMContext().getNullValue(LTy);
703   return ComplexPairTy(zeroConstant, zeroConstant);
704 }
705 
706 ComplexPairTy ComplexExprEmitter::VisitVAArgExpr(VAArgExpr *E) {
707   llvm::Value *ArgValue = CGF.EmitVAListRef(E->getSubExpr());
708   llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, E->getType());
709 
710   if (!ArgPtr) {
711     CGF.ErrorUnsupported(E, "complex va_arg expression");
712     const llvm::Type *EltTy =
713       CGF.ConvertType(E->getType()->getAsComplexType()->getElementType());
714     llvm::Value *U = llvm::UndefValue::get(EltTy);
715     return ComplexPairTy(U, U);
716   }
717 
718   // FIXME Volatility.
719   return EmitLoadOfComplex(ArgPtr, false);
720 }
721 
722 //===----------------------------------------------------------------------===//
723 //                         Entry Point into this File
724 //===----------------------------------------------------------------------===//
725 
726 /// EmitComplexExpr - Emit the computation of the specified expression of
727 /// complex type, ignoring the result.
728 ComplexPairTy CodeGenFunction::EmitComplexExpr(const Expr *E, bool IgnoreReal,
729                                                bool IgnoreImag, bool IgnoreRealAssign, bool IgnoreImagAssign) {
730   assert(E && E->getType()->isAnyComplexType() &&
731          "Invalid complex expression to emit");
732 
733   return ComplexExprEmitter(*this, IgnoreReal, IgnoreImag, IgnoreRealAssign,
734                             IgnoreImagAssign)
735     .Visit(const_cast<Expr*>(E));
736 }
737 
738 /// EmitComplexExprIntoAddr - Emit the computation of the specified expression
739 /// of complex type, storing into the specified Value*.
740 void CodeGenFunction::EmitComplexExprIntoAddr(const Expr *E,
741                                               llvm::Value *DestAddr,
742                                               bool DestIsVolatile) {
743   assert(E && E->getType()->isAnyComplexType() &&
744          "Invalid complex expression to emit");
745   ComplexExprEmitter Emitter(*this);
746   ComplexPairTy Val = Emitter.Visit(const_cast<Expr*>(E));
747   Emitter.EmitStoreOfComplex(Val, DestAddr, DestIsVolatile);
748 }
749 
750 /// StoreComplexToAddr - Store a complex number into the specified address.
751 void CodeGenFunction::StoreComplexToAddr(ComplexPairTy V,
752                                          llvm::Value *DestAddr,
753                                          bool DestIsVolatile) {
754   ComplexExprEmitter(*this).EmitStoreOfComplex(V, DestAddr, DestIsVolatile);
755 }
756 
757 /// LoadComplexFromAddr - Load a complex number from the specified address.
758 ComplexPairTy CodeGenFunction::LoadComplexFromAddr(llvm::Value *SrcAddr,
759                                                    bool SrcIsVolatile) {
760   return ComplexExprEmitter(*this).EmitLoadOfComplex(SrcAddr, SrcIsVolatile);
761 }
762