1 //===--- CGExprScalar.cpp - Emit LLVM Code for Scalar Exprs ---------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This contains code to emit Expr nodes with scalar LLVM types as LLVM code.
12 //===----------------------------------------------------------------------===//
14 #include "CodeGenFunction.h"
15 #include "CGObjCRuntime.h"
16 #include "CodeGenModule.h"
17 #include "clang/AST/ASTContext.h"
18 #include "clang/AST/DeclObjC.h"
19 #include "clang/AST/RecordLayout.h"
20 #include "clang/AST/StmtVisitor.h"
21 #include "clang/Basic/TargetInfo.h"
22 #include "llvm/Constants.h"
23 #include "llvm/Function.h"
24 #include "llvm/GlobalVariable.h"
25 #include "llvm/Intrinsics.h"
26 #include "llvm/Module.h"
27 #include "llvm/Support/Compiler.h"
28 #include "llvm/Support/CFG.h"
29 #include "llvm/Target/TargetData.h"
32 using namespace clang;
33 using namespace CodeGen;
36 //===----------------------------------------------------------------------===//
37 // Scalar Expression Emitter
38 //===----------------------------------------------------------------------===//
43 QualType Ty; // Computation Type.
44 const BinaryOperator *E;
48 class VISIBILITY_HIDDEN ScalarExprEmitter
49 : public StmtVisitor<ScalarExprEmitter, Value*> {
52 bool IgnoreResultAssign;
53 llvm::LLVMContext &VMContext;
56 ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false)
57 : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira),
58 VMContext(cgf.getLLVMContext()) {
61 //===--------------------------------------------------------------------===//
63 //===--------------------------------------------------------------------===//
65 bool TestAndClearIgnoreResultAssign() {
66 bool I = IgnoreResultAssign;
67 IgnoreResultAssign = false;
71 const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); }
72 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); }
74 Value *EmitLoadOfLValue(LValue LV, QualType T) {
75 return CGF.EmitLoadOfLValue(LV, T).getScalarVal();
78 /// EmitLoadOfLValue - Given an expression with complex type that represents a
79 /// value l-value, this method emits the address of the l-value, then loads
80 /// and returns the result.
81 Value *EmitLoadOfLValue(const Expr *E) {
82 return EmitLoadOfLValue(EmitLValue(E), E->getType());
85 /// EmitConversionToBool - Convert the specified expression value to a
86 /// boolean (i1) truth value. This is equivalent to "Val != 0".
87 Value *EmitConversionToBool(Value *Src, QualType DstTy);
89 /// EmitScalarConversion - Emit a conversion from the specified type to the
90 /// specified destination type, both of which are LLVM scalar types.
91 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy);
93 /// EmitComplexToScalarConversion - Emit a conversion from the specified
94 /// complex type to the specified destination type, where the destination type
95 /// is an LLVM scalar type.
96 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src,
97 QualType SrcTy, QualType DstTy);
99 //===--------------------------------------------------------------------===//
101 //===--------------------------------------------------------------------===//
103 Value *VisitStmt(Stmt *S) {
104 S->dump(CGF.getContext().getSourceManager());
105 assert(0 && "Stmt can't have complex result type!");
108 Value *VisitExpr(Expr *S);
110 Value *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); }
113 Value *VisitIntegerLiteral(const IntegerLiteral *E) {
114 return llvm::ConstantInt::get(VMContext, E->getValue());
116 Value *VisitFloatingLiteral(const FloatingLiteral *E) {
117 return llvm::ConstantFP::get(VMContext, E->getValue());
119 Value *VisitCharacterLiteral(const CharacterLiteral *E) {
120 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
122 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) {
123 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue());
125 Value *VisitCXXZeroInitValueExpr(const CXXZeroInitValueExpr *E) {
126 return llvm::Constant::getNullValue(ConvertType(E->getType()));
128 Value *VisitGNUNullExpr(const GNUNullExpr *E) {
129 return llvm::Constant::getNullValue(ConvertType(E->getType()));
131 Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) {
132 return llvm::ConstantInt::get(ConvertType(E->getType()),
133 CGF.getContext().typesAreCompatible(
134 E->getArgType1(), E->getArgType2()));
136 Value *VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E);
137 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) {
138 #ifndef USEINDIRECTBRANCH
140 llvm::ConstantInt::get(llvm::Type::getInt32Ty(CGF.getLLVMContext()),
141 CGF.GetIDForAddrOfLabel(E->getLabel()));
143 return Builder.CreateIntToPtr(V, ConvertType(E->getType()));
145 llvm::Value *V = CGF.GetAddrOfLabel(E->getLabel());
146 return Builder.CreateBitCast(V, ConvertType(E->getType()));
151 Value *VisitDeclRefExpr(DeclRefExpr *E) {
152 if (const EnumConstantDecl *EC = dyn_cast<EnumConstantDecl>(E->getDecl()))
153 return llvm::ConstantInt::get(VMContext, EC->getInitVal());
154 return EmitLoadOfLValue(E);
156 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) {
157 return CGF.EmitObjCSelectorExpr(E);
159 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) {
160 return CGF.EmitObjCProtocolExpr(E);
162 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) {
163 return EmitLoadOfLValue(E);
165 Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) {
166 return EmitLoadOfLValue(E);
168 Value *VisitObjCImplicitSetterGetterRefExpr(
169 ObjCImplicitSetterGetterRefExpr *E) {
170 return EmitLoadOfLValue(E);
172 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) {
173 return CGF.EmitObjCMessageExpr(E).getScalarVal();
176 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E);
177 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E);
178 Value *VisitMemberExpr(Expr *E) { return EmitLoadOfLValue(E); }
179 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); }
180 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
181 return EmitLoadOfLValue(E);
183 Value *VisitStringLiteral(Expr *E) { return EmitLValue(E).getAddress(); }
184 Value *VisitObjCEncodeExpr(const ObjCEncodeExpr *E) {
185 return EmitLValue(E).getAddress();
188 Value *VisitPredefinedExpr(Expr *E) { return EmitLValue(E).getAddress(); }
190 Value *VisitInitListExpr(InitListExpr *E);
192 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) {
193 return llvm::Constant::getNullValue(ConvertType(E->getType()));
195 Value *VisitCastExpr(const CastExpr *E) {
196 // Make sure to evaluate VLA bounds now so that we have them for later.
197 if (E->getType()->isVariablyModifiedType())
198 CGF.EmitVLASize(E->getType());
200 return EmitCastExpr(E);
202 Value *EmitCastExpr(const CastExpr *E);
204 Value *VisitCallExpr(const CallExpr *E) {
205 if (E->getCallReturnType()->isReferenceType())
206 return EmitLoadOfLValue(E);
208 return CGF.EmitCallExpr(E).getScalarVal();
211 Value *VisitStmtExpr(const StmtExpr *E);
213 Value *VisitBlockDeclRefExpr(const BlockDeclRefExpr *E);
216 Value *VisitPrePostIncDec(const UnaryOperator *E, bool isInc, bool isPre);
217 Value *VisitUnaryPostDec(const UnaryOperator *E) {
218 return VisitPrePostIncDec(E, false, false);
220 Value *VisitUnaryPostInc(const UnaryOperator *E) {
221 return VisitPrePostIncDec(E, true, false);
223 Value *VisitUnaryPreDec(const UnaryOperator *E) {
224 return VisitPrePostIncDec(E, false, true);
226 Value *VisitUnaryPreInc(const UnaryOperator *E) {
227 return VisitPrePostIncDec(E, true, true);
229 Value *VisitUnaryAddrOf(const UnaryOperator *E) {
230 return EmitLValue(E->getSubExpr()).getAddress();
232 Value *VisitUnaryDeref(const Expr *E) { return EmitLoadOfLValue(E); }
233 Value *VisitUnaryPlus(const UnaryOperator *E) {
234 // This differs from gcc, though, most likely due to a bug in gcc.
235 TestAndClearIgnoreResultAssign();
236 return Visit(E->getSubExpr());
238 Value *VisitUnaryMinus (const UnaryOperator *E);
239 Value *VisitUnaryNot (const UnaryOperator *E);
240 Value *VisitUnaryLNot (const UnaryOperator *E);
241 Value *VisitUnaryReal (const UnaryOperator *E);
242 Value *VisitUnaryImag (const UnaryOperator *E);
243 Value *VisitUnaryExtension(const UnaryOperator *E) {
244 return Visit(E->getSubExpr());
246 Value *VisitUnaryOffsetOf(const UnaryOperator *E);
249 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) {
250 return Visit(DAE->getExpr());
252 Value *VisitCXXThisExpr(CXXThisExpr *TE) {
253 return CGF.LoadCXXThis();
256 Value *VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) {
257 return CGF.EmitCXXExprWithTemporaries(E).getScalarVal();
259 Value *VisitCXXNewExpr(const CXXNewExpr *E) {
260 return CGF.EmitCXXNewExpr(E);
262 Value *VisitCXXDeleteExpr(const CXXDeleteExpr *E) {
263 CGF.EmitCXXDeleteExpr(E);
267 Value *VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) {
268 // C++ [expr.pseudo]p1:
269 // The result shall only be used as the operand for the function call
270 // operator (), and the result of such a call has type void. The only
271 // effect is the evaluation of the postfix-expression before the dot or
273 CGF.EmitScalarExpr(E->getBase());
277 Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) {
278 return llvm::Constant::getNullValue(ConvertType(E->getType()));
281 Value *VisitCXXThrowExpr(const CXXThrowExpr *E) {
282 CGF.EmitCXXThrowExpr(E);
287 Value *EmitMul(const BinOpInfo &Ops) {
288 if (CGF.getContext().getLangOptions().OverflowChecking
289 && Ops.Ty->isSignedIntegerType())
290 return EmitOverflowCheckedBinOp(Ops);
291 if (Ops.LHS->getType()->isFPOrFPVector())
292 return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul");
293 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul");
295 /// Create a binary op that checks for overflow.
296 /// Currently only supports +, - and *.
297 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops);
298 Value *EmitDiv(const BinOpInfo &Ops);
299 Value *EmitRem(const BinOpInfo &Ops);
300 Value *EmitAdd(const BinOpInfo &Ops);
301 Value *EmitSub(const BinOpInfo &Ops);
302 Value *EmitShl(const BinOpInfo &Ops);
303 Value *EmitShr(const BinOpInfo &Ops);
304 Value *EmitAnd(const BinOpInfo &Ops) {
305 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and");
307 Value *EmitXor(const BinOpInfo &Ops) {
308 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor");
310 Value *EmitOr (const BinOpInfo &Ops) {
311 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or");
314 BinOpInfo EmitBinOps(const BinaryOperator *E);
315 Value *EmitCompoundAssign(const CompoundAssignOperator *E,
316 Value *(ScalarExprEmitter::*F)(const BinOpInfo &));
318 // Binary operators and binary compound assignment operators.
319 #define HANDLEBINOP(OP) \
320 Value *VisitBin ## OP(const BinaryOperator *E) { \
321 return Emit ## OP(EmitBinOps(E)); \
323 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \
324 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \
339 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc,
340 unsigned SICmpOpc, unsigned FCmpOpc);
341 #define VISITCOMP(CODE, UI, SI, FP) \
342 Value *VisitBin##CODE(const BinaryOperator *E) { \
343 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \
344 llvm::FCmpInst::FP); }
345 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT);
346 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT);
347 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE);
348 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE);
349 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ);
350 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE);
353 Value *VisitBinAssign (const BinaryOperator *E);
355 Value *VisitBinLAnd (const BinaryOperator *E);
356 Value *VisitBinLOr (const BinaryOperator *E);
357 Value *VisitBinComma (const BinaryOperator *E);
360 Value *VisitBlockExpr(const BlockExpr *BE);
361 Value *VisitConditionalOperator(const ConditionalOperator *CO);
362 Value *VisitChooseExpr(ChooseExpr *CE);
363 Value *VisitVAArgExpr(VAArgExpr *VE);
364 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) {
365 return CGF.EmitObjCStringLiteral(E);
368 } // end anonymous namespace.
370 //===----------------------------------------------------------------------===//
372 //===----------------------------------------------------------------------===//
374 /// EmitConversionToBool - Convert the specified expression value to a
375 /// boolean (i1) truth value. This is equivalent to "Val != 0".
376 Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) {
377 assert(SrcType.isCanonical() && "EmitScalarConversion strips typedefs");
379 if (SrcType->isRealFloatingType()) {
380 // Compare against 0.0 for fp scalars.
381 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType());
382 return Builder.CreateFCmpUNE(Src, Zero, "tobool");
385 if (SrcType->isMemberPointerType()) {
386 // FIXME: This is ABI specific.
388 // Compare against -1.
389 llvm::Value *NegativeOne = llvm::Constant::getAllOnesValue(Src->getType());
390 return Builder.CreateICmpNE(Src, NegativeOne, "tobool");
393 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) &&
394 "Unknown scalar type to convert");
396 // Because of the type rules of C, we often end up computing a logical value,
397 // then zero extending it to int, then wanting it as a logical value again.
398 // Optimize this common case.
399 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) {
400 if (ZI->getOperand(0)->getType() ==
401 llvm::Type::getInt1Ty(CGF.getLLVMContext())) {
402 Value *Result = ZI->getOperand(0);
403 // If there aren't any more uses, zap the instruction to save space.
404 // Note that there can be more uses, for example if this
405 // is the result of an assignment.
407 ZI->eraseFromParent();
412 // Compare against an integer or pointer null.
413 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType());
414 return Builder.CreateICmpNE(Src, Zero, "tobool");
417 /// EmitScalarConversion - Emit a conversion from the specified type to the
418 /// specified destination type, both of which are LLVM scalar types.
419 Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType,
421 SrcType = CGF.getContext().getCanonicalType(SrcType);
422 DstType = CGF.getContext().getCanonicalType(DstType);
423 if (SrcType == DstType) return Src;
425 if (DstType->isVoidType()) return 0;
427 llvm::LLVMContext &VMContext = CGF.getLLVMContext();
429 // Handle conversions to bool first, they are special: comparisons against 0.
430 if (DstType->isBooleanType())
431 return EmitConversionToBool(Src, SrcType);
433 const llvm::Type *DstTy = ConvertType(DstType);
435 // Ignore conversions like int -> uint.
436 if (Src->getType() == DstTy)
439 // Handle pointer conversions next: pointers can only be converted to/from
440 // other pointers and integers. Check for pointer types in terms of LLVM, as
441 // some native types (like Obj-C id) may map to a pointer type.
442 if (isa<llvm::PointerType>(DstTy)) {
443 // The source value may be an integer, or a pointer.
444 if (isa<llvm::PointerType>(Src->getType()))
445 return Builder.CreateBitCast(Src, DstTy, "conv");
447 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?");
448 // First, convert to the correct width so that we control the kind of
450 const llvm::Type *MiddleTy =
451 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth);
452 bool InputSigned = SrcType->isSignedIntegerType();
453 llvm::Value* IntResult =
454 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv");
455 // Then, cast to pointer.
456 return Builder.CreateIntToPtr(IntResult, DstTy, "conv");
459 if (isa<llvm::PointerType>(Src->getType())) {
460 // Must be an ptr to int cast.
461 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?");
462 return Builder.CreatePtrToInt(Src, DstTy, "conv");
465 // A scalar can be splatted to an extended vector of the same element type
466 if (DstType->isExtVectorType() && !SrcType->isVectorType()) {
467 // Cast the scalar to element type
468 QualType EltTy = DstType->getAs<ExtVectorType>()->getElementType();
469 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy);
471 // Insert the element in element zero of an undef vector
472 llvm::Value *UnV = llvm::UndefValue::get(DstTy);
474 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 0);
475 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp");
477 // Splat the element across to all elements
478 llvm::SmallVector<llvm::Constant*, 16> Args;
479 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements();
480 for (unsigned i = 0; i < NumElements; i++)
481 Args.push_back(llvm::ConstantInt::get(
482 llvm::Type::getInt32Ty(VMContext), 0));
484 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements);
485 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat");
489 // Allow bitcast from vector to integer/fp of the same size.
490 if (isa<llvm::VectorType>(Src->getType()) ||
491 isa<llvm::VectorType>(DstTy))
492 return Builder.CreateBitCast(Src, DstTy, "conv");
494 // Finally, we have the arithmetic types: real int/float.
495 if (isa<llvm::IntegerType>(Src->getType())) {
496 bool InputSigned = SrcType->isSignedIntegerType();
497 if (isa<llvm::IntegerType>(DstTy))
498 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv");
499 else if (InputSigned)
500 return Builder.CreateSIToFP(Src, DstTy, "conv");
502 return Builder.CreateUIToFP(Src, DstTy, "conv");
505 assert(Src->getType()->isFloatingPoint() && "Unknown real conversion");
506 if (isa<llvm::IntegerType>(DstTy)) {
507 if (DstType->isSignedIntegerType())
508 return Builder.CreateFPToSI(Src, DstTy, "conv");
510 return Builder.CreateFPToUI(Src, DstTy, "conv");
513 assert(DstTy->isFloatingPoint() && "Unknown real conversion");
514 if (DstTy->getTypeID() < Src->getType()->getTypeID())
515 return Builder.CreateFPTrunc(Src, DstTy, "conv");
517 return Builder.CreateFPExt(Src, DstTy, "conv");
520 /// EmitComplexToScalarConversion - Emit a conversion from the specified complex
521 /// type to the specified destination type, where the destination type is an
522 /// LLVM scalar type.
523 Value *ScalarExprEmitter::
524 EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src,
525 QualType SrcTy, QualType DstTy) {
526 // Get the source element type.
527 SrcTy = SrcTy->getAs<ComplexType>()->getElementType();
529 // Handle conversions to bool first, they are special: comparisons against 0.
530 if (DstTy->isBooleanType()) {
531 // Complex != 0 -> (Real != 0) | (Imag != 0)
532 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy);
533 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy);
534 return Builder.CreateOr(Src.first, Src.second, "tobool");
537 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type,
538 // the imaginary part of the complex value is discarded and the value of the
539 // real part is converted according to the conversion rules for the
540 // corresponding real type.
541 return EmitScalarConversion(Src.first, SrcTy, DstTy);
545 //===----------------------------------------------------------------------===//
547 //===----------------------------------------------------------------------===//
549 Value *ScalarExprEmitter::VisitExpr(Expr *E) {
550 if (const BinaryOperator *BExpr = dyn_cast<BinaryOperator>(E))
551 if (BExpr->getOpcode() == BinaryOperator::PtrMemD) {
552 LValue LV = CGF.EmitPointerToDataMemberBinaryExpr(BExpr);
553 Value *InVal = CGF.EmitLoadOfLValue(LV, E->getType()).getScalarVal();
557 CGF.ErrorUnsupported(E, "scalar expression");
558 if (E->getType()->isVoidType())
560 return llvm::UndefValue::get(CGF.ConvertType(E->getType()));
563 Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) {
564 llvm::SmallVector<llvm::Constant*, 32> indices;
565 for (unsigned i = 2; i < E->getNumSubExprs(); i++) {
566 indices.push_back(cast<llvm::Constant>(CGF.EmitScalarExpr(E->getExpr(i))));
568 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0));
569 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1));
570 Value* SV = llvm::ConstantVector::get(indices.begin(), indices.size());
571 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle");
574 Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) {
575 TestAndClearIgnoreResultAssign();
577 // Emit subscript expressions in rvalue context's. For most cases, this just
578 // loads the lvalue formed by the subscript expr. However, we have to be
579 // careful, because the base of a vector subscript is occasionally an rvalue,
580 // so we can't get it as an lvalue.
581 if (!E->getBase()->getType()->isVectorType())
582 return EmitLoadOfLValue(E);
584 // Handle the vector case. The base must be a vector, the index must be an
586 Value *Base = Visit(E->getBase());
587 Value *Idx = Visit(E->getIdx());
588 bool IdxSigned = E->getIdx()->getType()->isSignedIntegerType();
589 Idx = Builder.CreateIntCast(Idx,
590 llvm::Type::getInt32Ty(CGF.getLLVMContext()),
593 return Builder.CreateExtractElement(Base, Idx, "vecext");
596 static llvm::Constant *getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx,
597 unsigned Off, const llvm::Type *I32Ty) {
598 int MV = SVI->getMaskValue(Idx);
600 return llvm::UndefValue::get(I32Ty);
601 return llvm::ConstantInt::get(I32Ty, Off+MV);
604 Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) {
605 bool Ignore = TestAndClearIgnoreResultAssign();
607 assert (Ignore == false && "init list ignored");
608 unsigned NumInitElements = E->getNumInits();
610 if (E->hadArrayRangeDesignator())
611 CGF.ErrorUnsupported(E, "GNU array range designator extension");
613 const llvm::VectorType *VType =
614 dyn_cast<llvm::VectorType>(ConvertType(E->getType()));
616 // We have a scalar in braces. Just use the first element.
618 return Visit(E->getInit(0));
620 unsigned ResElts = VType->getNumElements();
621 const llvm::Type *I32Ty = llvm::Type::getInt32Ty(CGF.getLLVMContext());
623 // Loop over initializers collecting the Value for each, and remembering
624 // whether the source was swizzle (ExtVectorElementExpr). This will allow
625 // us to fold the shuffle for the swizzle into the shuffle for the vector
626 // initializer, since LLVM optimizers generally do not want to touch
629 bool VIsUndefShuffle = false;
630 llvm::Value *V = llvm::UndefValue::get(VType);
631 for (unsigned i = 0; i != NumInitElements; ++i) {
632 Expr *IE = E->getInit(i);
633 Value *Init = Visit(IE);
634 llvm::SmallVector<llvm::Constant*, 16> Args;
636 const llvm::VectorType *VVT = dyn_cast<llvm::VectorType>(Init->getType());
638 // Handle scalar elements. If the scalar initializer is actually one
639 // element of a different vector of the same width, use shuffle instead of
642 if (isa<ExtVectorElementExpr>(IE)) {
643 llvm::ExtractElementInst *EI = cast<llvm::ExtractElementInst>(Init);
645 if (EI->getVectorOperandType()->getNumElements() == ResElts) {
646 llvm::ConstantInt *C = cast<llvm::ConstantInt>(EI->getIndexOperand());
647 Value *LHS = 0, *RHS = 0;
649 // insert into undef -> shuffle (src, undef)
651 for (unsigned j = 1; j != ResElts; ++j)
652 Args.push_back(llvm::UndefValue::get(I32Ty));
654 LHS = EI->getVectorOperand();
656 VIsUndefShuffle = true;
657 } else if (VIsUndefShuffle) {
658 // insert into undefshuffle && size match -> shuffle (v, src)
659 llvm::ShuffleVectorInst *SVV = cast<llvm::ShuffleVectorInst>(V);
660 for (unsigned j = 0; j != CurIdx; ++j)
661 Args.push_back(getMaskElt(SVV, j, 0, I32Ty));
662 Args.push_back(llvm::ConstantInt::get(I32Ty,
663 ResElts + C->getZExtValue()));
664 for (unsigned j = CurIdx + 1; j != ResElts; ++j)
665 Args.push_back(llvm::UndefValue::get(I32Ty));
667 LHS = cast<llvm::ShuffleVectorInst>(V)->getOperand(0);
668 RHS = EI->getVectorOperand();
669 VIsUndefShuffle = false;
672 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts);
673 V = Builder.CreateShuffleVector(LHS, RHS, Mask);
679 Value *Idx = llvm::ConstantInt::get(I32Ty, CurIdx);
680 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit");
681 VIsUndefShuffle = false;
686 unsigned InitElts = VVT->getNumElements();
688 // If the initializer is an ExtVecEltExpr (a swizzle), and the swizzle's
689 // input is the same width as the vector being constructed, generate an
690 // optimized shuffle of the swizzle input into the result.
691 unsigned Offset = (CurIdx == 0) ? 0 : ResElts;
692 if (isa<ExtVectorElementExpr>(IE)) {
693 llvm::ShuffleVectorInst *SVI = cast<llvm::ShuffleVectorInst>(Init);
694 Value *SVOp = SVI->getOperand(0);
695 const llvm::VectorType *OpTy = cast<llvm::VectorType>(SVOp->getType());
697 if (OpTy->getNumElements() == ResElts) {
698 for (unsigned j = 0; j != CurIdx; ++j) {
699 // If the current vector initializer is a shuffle with undef, merge
700 // this shuffle directly into it.
701 if (VIsUndefShuffle) {
702 Args.push_back(getMaskElt(cast<llvm::ShuffleVectorInst>(V), j, 0,
705 Args.push_back(llvm::ConstantInt::get(I32Ty, j));
708 for (unsigned j = 0, je = InitElts; j != je; ++j)
709 Args.push_back(getMaskElt(SVI, j, Offset, I32Ty));
710 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j)
711 Args.push_back(llvm::UndefValue::get(I32Ty));
714 V = cast<llvm::ShuffleVectorInst>(V)->getOperand(0);
720 // Extend init to result vector length, and then shuffle its contribution
721 // to the vector initializer into V.
723 for (unsigned j = 0; j != InitElts; ++j)
724 Args.push_back(llvm::ConstantInt::get(I32Ty, j));
725 for (unsigned j = InitElts; j != ResElts; ++j)
726 Args.push_back(llvm::UndefValue::get(I32Ty));
727 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts);
728 Init = Builder.CreateShuffleVector(Init, llvm::UndefValue::get(VVT),
732 for (unsigned j = 0; j != CurIdx; ++j)
733 Args.push_back(llvm::ConstantInt::get(I32Ty, j));
734 for (unsigned j = 0; j != InitElts; ++j)
735 Args.push_back(llvm::ConstantInt::get(I32Ty, j+Offset));
736 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j)
737 Args.push_back(llvm::UndefValue::get(I32Ty));
740 // If V is undef, make sure it ends up on the RHS of the shuffle to aid
741 // merging subsequent shuffles into this one.
744 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts);
745 V = Builder.CreateShuffleVector(V, Init, Mask, "vecinit");
746 VIsUndefShuffle = isa<llvm::UndefValue>(Init);
750 // FIXME: evaluate codegen vs. shuffling against constant null vector.
751 // Emit remaining default initializers.
752 const llvm::Type *EltTy = VType->getElementType();
754 // Emit remaining default initializers
755 for (/* Do not initialize i*/; CurIdx < ResElts; ++CurIdx) {
756 Value *Idx = llvm::ConstantInt::get(I32Ty, CurIdx);
757 llvm::Value *Init = llvm::Constant::getNullValue(EltTy);
758 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit");
763 // VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts
764 // have to handle a more broad range of conversions than explicit casts, as they
765 // handle things like function to ptr-to-function decay etc.
766 Value *ScalarExprEmitter::EmitCastExpr(const CastExpr *CE) {
767 const Expr *E = CE->getSubExpr();
768 QualType DestTy = CE->getType();
769 CastExpr::CastKind Kind = CE->getCastKind();
771 if (!DestTy->isVoidType())
772 TestAndClearIgnoreResultAssign();
776 // FIXME: Assert here.
777 // assert(0 && "Unhandled cast kind!");
779 case CastExpr::CK_Unknown:
780 // FIXME: We should really assert here - Unknown casts should never get
781 // as far as to codegen.
783 case CastExpr::CK_BitCast: {
784 Value *Src = Visit(const_cast<Expr*>(E));
785 return Builder.CreateBitCast(Src, ConvertType(DestTy));
787 case CastExpr::CK_ArrayToPointerDecay: {
788 assert(E->getType()->isArrayType() &&
789 "Array to pointer decay must have array source type!");
791 Value *V = EmitLValue(E).getAddress(); // Bitfields can't be arrays.
793 // Note that VLA pointers are always decayed, so we don't need to do
795 if (!E->getType()->isVariableArrayType()) {
796 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer");
797 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType())
798 ->getElementType()) &&
799 "Expected pointer to array");
800 V = Builder.CreateStructGEP(V, 0, "arraydecay");
803 // The resultant pointer type can be implicitly casted to other pointer
804 // types as well (e.g. void*) and can be implicitly converted to integer.
805 const llvm::Type *DestLTy = ConvertType(DestTy);
806 if (V->getType() != DestLTy) {
807 if (isa<llvm::PointerType>(DestLTy))
808 V = Builder.CreateBitCast(V, DestLTy, "ptrconv");
810 assert(isa<llvm::IntegerType>(DestLTy) && "Unknown array decay");
811 V = Builder.CreatePtrToInt(V, DestLTy, "ptrconv");
816 case CastExpr::CK_NullToMemberPointer:
817 return CGF.CGM.EmitNullConstant(DestTy);
819 case CastExpr::CK_DerivedToBase: {
820 const RecordType *DerivedClassTy =
821 E->getType()->getAs<PointerType>()->getPointeeType()->getAs<RecordType>();
822 CXXRecordDecl *DerivedClassDecl =
823 cast<CXXRecordDecl>(DerivedClassTy->getDecl());
825 const RecordType *BaseClassTy =
826 DestTy->getAs<PointerType>()->getPointeeType()->getAs<RecordType>();
827 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseClassTy->getDecl());
829 Value *Src = Visit(const_cast<Expr*>(E));
831 bool NullCheckValue = true;
833 if (isa<CXXThisExpr>(E)) {
834 // We always assume that 'this' is never null.
835 NullCheckValue = false;
836 } else if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(CE)) {
837 // And that lvalue casts are never null.
838 if (ICE->isLvalueCast())
839 NullCheckValue = false;
841 return CGF.GetAddressCXXOfBaseClass(Src, DerivedClassDecl, BaseClassDecl,
845 case CastExpr::CK_IntegralToPointer: {
846 Value *Src = Visit(const_cast<Expr*>(E));
848 // First, convert to the correct width so that we control the kind of
850 const llvm::Type *MiddleTy =
851 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth);
852 bool InputSigned = E->getType()->isSignedIntegerType();
853 llvm::Value* IntResult =
854 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv");
856 return Builder.CreateIntToPtr(IntResult, ConvertType(DestTy));
859 case CastExpr::CK_PointerToIntegral: {
860 Value *Src = Visit(const_cast<Expr*>(E));
861 return Builder.CreatePtrToInt(Src, ConvertType(DestTy));
866 // Handle cases where the source is an non-complex type.
868 if (!CGF.hasAggregateLLVMType(E->getType())) {
869 Value *Src = Visit(const_cast<Expr*>(E));
871 // Use EmitScalarConversion to perform the conversion.
872 return EmitScalarConversion(Src, E->getType(), DestTy);
875 if (E->getType()->isAnyComplexType()) {
876 // Handle cases where the source is a complex type.
877 bool IgnoreImag = true;
878 bool IgnoreImagAssign = true;
879 bool IgnoreReal = IgnoreResultAssign;
880 bool IgnoreRealAssign = IgnoreResultAssign;
881 if (DestTy->isBooleanType())
882 IgnoreImagAssign = IgnoreImag = false;
883 else if (DestTy->isVoidType()) {
884 IgnoreReal = IgnoreImag = false;
885 IgnoreRealAssign = IgnoreImagAssign = true;
887 CodeGenFunction::ComplexPairTy V
888 = CGF.EmitComplexExpr(E, IgnoreReal, IgnoreImag, IgnoreRealAssign,
890 return EmitComplexToScalarConversion(V, E->getType(), DestTy);
893 // Okay, this is a cast from an aggregate. It must be a cast to void. Just
894 // evaluate the result and return.
895 CGF.EmitAggExpr(E, 0, false, true);
899 Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) {
900 return CGF.EmitCompoundStmt(*E->getSubStmt(),
901 !E->getType()->isVoidType()).getScalarVal();
904 Value *ScalarExprEmitter::VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) {
905 llvm::Value *V = CGF.GetAddrOfBlockDecl(E);
906 if (E->getType().isObjCGCWeak())
907 return CGF.CGM.getObjCRuntime().EmitObjCWeakRead(CGF, V);
908 return Builder.CreateLoad(V, false, "tmp");
911 //===----------------------------------------------------------------------===//
913 //===----------------------------------------------------------------------===//
915 Value *ScalarExprEmitter::VisitPrePostIncDec(const UnaryOperator *E,
916 bool isInc, bool isPre) {
917 LValue LV = EmitLValue(E->getSubExpr());
918 QualType ValTy = E->getSubExpr()->getType();
919 Value *InVal = CGF.EmitLoadOfLValue(LV, ValTy).getScalarVal();
921 llvm::LLVMContext &VMContext = CGF.getLLVMContext();
923 int AmountVal = isInc ? 1 : -1;
925 if (ValTy->isPointerType() &&
926 ValTy->getAs<PointerType>()->isVariableArrayType()) {
927 // The amount of the addition/subtraction needs to account for the VLA size
928 CGF.ErrorUnsupported(E, "VLA pointer inc/dec");
932 if (const llvm::PointerType *PT =
933 dyn_cast<llvm::PointerType>(InVal->getType())) {
934 llvm::Constant *Inc =
935 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), AmountVal);
936 if (!isa<llvm::FunctionType>(PT->getElementType())) {
937 QualType PTEE = ValTy->getPointeeType();
938 if (const ObjCInterfaceType *OIT =
939 dyn_cast<ObjCInterfaceType>(PTEE)) {
940 // Handle interface types, which are not represented with a concrete type.
941 int size = CGF.getContext().getTypeSize(OIT) / 8;
944 Inc = llvm::ConstantInt::get(Inc->getType(), size);
945 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext);
946 InVal = Builder.CreateBitCast(InVal, i8Ty);
947 NextVal = Builder.CreateGEP(InVal, Inc, "add.ptr");
948 llvm::Value *lhs = LV.getAddress();
949 lhs = Builder.CreateBitCast(lhs, llvm::PointerType::getUnqual(i8Ty));
950 LV = LValue::MakeAddr(lhs, CGF.MakeQualifiers(ValTy));
952 NextVal = Builder.CreateInBoundsGEP(InVal, Inc, "ptrincdec");
954 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext);
955 NextVal = Builder.CreateBitCast(InVal, i8Ty, "tmp");
956 NextVal = Builder.CreateGEP(NextVal, Inc, "ptrincdec");
957 NextVal = Builder.CreateBitCast(NextVal, InVal->getType());
959 } else if (InVal->getType() == llvm::Type::getInt1Ty(VMContext) && isInc) {
960 // Bool++ is an interesting case, due to promotion rules, we get:
961 // Bool++ -> Bool = Bool+1 -> Bool = (int)Bool+1 ->
962 // Bool = ((int)Bool+1) != 0
963 // An interesting aspect of this is that increment is always true.
964 // Decrement does not have this property.
965 NextVal = llvm::ConstantInt::getTrue(VMContext);
966 } else if (isa<llvm::IntegerType>(InVal->getType())) {
967 NextVal = llvm::ConstantInt::get(InVal->getType(), AmountVal);
969 // Signed integer overflow is undefined behavior.
970 if (ValTy->isSignedIntegerType())
971 NextVal = Builder.CreateNSWAdd(InVal, NextVal, isInc ? "inc" : "dec");
973 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec");
975 // Add the inc/dec to the real part.
976 if (InVal->getType()->isFloatTy())
978 llvm::ConstantFP::get(VMContext,
979 llvm::APFloat(static_cast<float>(AmountVal)));
980 else if (InVal->getType()->isDoubleTy())
982 llvm::ConstantFP::get(VMContext,
983 llvm::APFloat(static_cast<double>(AmountVal)));
985 llvm::APFloat F(static_cast<float>(AmountVal));
987 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero,
989 NextVal = llvm::ConstantFP::get(VMContext, F);
991 NextVal = Builder.CreateFAdd(InVal, NextVal, isInc ? "inc" : "dec");
994 // Store the updated result through the lvalue.
996 CGF.EmitStoreThroughBitfieldLValue(RValue::get(NextVal), LV, ValTy,
999 CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, ValTy);
1001 // If this is a postinc, return the value read from memory, otherwise use the
1003 return isPre ? NextVal : InVal;
1007 Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) {
1008 TestAndClearIgnoreResultAssign();
1009 Value *Op = Visit(E->getSubExpr());
1010 if (Op->getType()->isFPOrFPVector())
1011 return Builder.CreateFNeg(Op, "neg");
1012 return Builder.CreateNeg(Op, "neg");
1015 Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) {
1016 TestAndClearIgnoreResultAssign();
1017 Value *Op = Visit(E->getSubExpr());
1018 return Builder.CreateNot(Op, "neg");
1021 Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) {
1022 // Compare operand to zero.
1023 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr());
1026 // TODO: Could dynamically modify easy computations here. For example, if
1027 // the operand is an icmp ne, turn into icmp eq.
1028 BoolVal = Builder.CreateNot(BoolVal, "lnot");
1030 // ZExt result to the expr type.
1031 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext");
1034 /// VisitSizeOfAlignOfExpr - Return the size or alignment of the type of
1035 /// argument of the sizeof expression as an integer.
1037 ScalarExprEmitter::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) {
1038 QualType TypeToSize = E->getTypeOfArgument();
1039 if (E->isSizeOf()) {
1040 if (const VariableArrayType *VAT =
1041 CGF.getContext().getAsVariableArrayType(TypeToSize)) {
1042 if (E->isArgumentType()) {
1043 // sizeof(type) - make sure to emit the VLA size.
1044 CGF.EmitVLASize(TypeToSize);
1046 // C99 6.5.3.4p2: If the argument is an expression of type
1047 // VLA, it is evaluated.
1048 CGF.EmitAnyExpr(E->getArgumentExpr());
1051 return CGF.GetVLASize(VAT);
1055 // If this isn't sizeof(vla), the result must be constant; use the constant
1056 // folding logic so we don't have to duplicate it here.
1057 Expr::EvalResult Result;
1058 E->Evaluate(Result, CGF.getContext());
1059 return llvm::ConstantInt::get(VMContext, Result.Val.getInt());
1062 Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) {
1063 Expr *Op = E->getSubExpr();
1064 if (Op->getType()->isAnyComplexType())
1065 return CGF.EmitComplexExpr(Op, false, true, false, true).first;
1068 Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) {
1069 Expr *Op = E->getSubExpr();
1070 if (Op->getType()->isAnyComplexType())
1071 return CGF.EmitComplexExpr(Op, true, false, true, false).second;
1073 // __imag on a scalar returns zero. Emit the subexpr to ensure side
1074 // effects are evaluated, but not the actual value.
1075 if (E->isLvalue(CGF.getContext()) == Expr::LV_Valid)
1078 CGF.EmitScalarExpr(Op, true);
1079 return llvm::Constant::getNullValue(ConvertType(E->getType()));
1082 Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) {
1083 Value* ResultAsPtr = EmitLValue(E->getSubExpr()).getAddress();
1084 const llvm::Type* ResultType = ConvertType(E->getType());
1085 return Builder.CreatePtrToInt(ResultAsPtr, ResultType, "offsetof");
1088 //===----------------------------------------------------------------------===//
1090 //===----------------------------------------------------------------------===//
1092 BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) {
1093 TestAndClearIgnoreResultAssign();
1095 Result.LHS = Visit(E->getLHS());
1096 Result.RHS = Visit(E->getRHS());
1097 Result.Ty = E->getType();
1102 Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E,
1103 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) {
1104 bool Ignore = TestAndClearIgnoreResultAssign();
1105 QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType();
1109 if (E->getComputationResultType()->isAnyComplexType()) {
1110 // This needs to go through the complex expression emitter, but it's a tad
1111 // complicated to do that... I'm leaving it out for now. (Note that we do
1112 // actually need the imaginary part of the RHS for multiplication and
1114 CGF.ErrorUnsupported(E, "complex compound assignment");
1115 return llvm::UndefValue::get(CGF.ConvertType(E->getType()));
1118 // Emit the RHS first. __block variables need to have the rhs evaluated
1119 // first, plus this should improve codegen a little.
1120 OpInfo.RHS = Visit(E->getRHS());
1121 OpInfo.Ty = E->getComputationResultType();
1123 // Load/convert the LHS.
1124 LValue LHSLV = EmitLValue(E->getLHS());
1125 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy);
1126 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy,
1127 E->getComputationLHSType());
1129 // Expand the binary operator.
1130 Value *Result = (this->*Func)(OpInfo);
1132 // Convert the result back to the LHS type.
1133 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy);
1135 // Store the result value into the LHS lvalue. Bit-fields are handled
1136 // specially because the result is altered by the store, i.e., [C99 6.5.16p1]
1137 // 'An assignment expression has the value of the left operand after the
1139 if (LHSLV.isBitfield()) {
1140 if (!LHSLV.isVolatileQualified()) {
1141 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy,
1145 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy);
1147 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy);
1150 return EmitLoadOfLValue(LHSLV, E->getType());
1154 Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) {
1155 if (Ops.LHS->getType()->isFPOrFPVector())
1156 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div");
1157 else if (Ops.Ty->isUnsignedIntegerType())
1158 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div");
1160 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div");
1163 Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) {
1164 // Rem in C can't be a floating point type: C99 6.5.5p2.
1165 if (Ops.Ty->isUnsignedIntegerType())
1166 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem");
1168 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem");
1171 Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) {
1175 switch (Ops.E->getOpcode()) {
1176 case BinaryOperator::Add:
1177 case BinaryOperator::AddAssign:
1179 IID = llvm::Intrinsic::sadd_with_overflow;
1181 case BinaryOperator::Sub:
1182 case BinaryOperator::SubAssign:
1184 IID = llvm::Intrinsic::ssub_with_overflow;
1186 case BinaryOperator::Mul:
1187 case BinaryOperator::MulAssign:
1189 IID = llvm::Intrinsic::smul_with_overflow;
1192 assert(false && "Unsupported operation for overflow detection");
1198 const llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty);
1200 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, &opTy, 1);
1202 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS);
1203 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0);
1204 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1);
1206 // Branch in case of overflow.
1207 llvm::BasicBlock *initialBB = Builder.GetInsertBlock();
1208 llvm::BasicBlock *overflowBB =
1209 CGF.createBasicBlock("overflow", CGF.CurFn);
1210 llvm::BasicBlock *continueBB =
1211 CGF.createBasicBlock("overflow.continue", CGF.CurFn);
1213 Builder.CreateCondBr(overflow, overflowBB, continueBB);
1217 Builder.SetInsertPoint(overflowBB);
1220 // long long *__overflow_handler)(long long a, long long b, char op,
1222 std::vector<const llvm::Type*> handerArgTypes;
1223 handerArgTypes.push_back(llvm::Type::getInt64Ty(VMContext));
1224 handerArgTypes.push_back(llvm::Type::getInt64Ty(VMContext));
1225 handerArgTypes.push_back(llvm::Type::getInt8Ty(VMContext));
1226 handerArgTypes.push_back(llvm::Type::getInt8Ty(VMContext));
1227 llvm::FunctionType *handlerTy = llvm::FunctionType::get(
1228 llvm::Type::getInt64Ty(VMContext), handerArgTypes, false);
1229 llvm::Value *handlerFunction =
1230 CGF.CGM.getModule().getOrInsertGlobal("__overflow_handler",
1231 llvm::PointerType::getUnqual(handlerTy));
1232 handlerFunction = Builder.CreateLoad(handlerFunction);
1234 llvm::Value *handlerResult = Builder.CreateCall4(handlerFunction,
1235 Builder.CreateSExt(Ops.LHS, llvm::Type::getInt64Ty(VMContext)),
1236 Builder.CreateSExt(Ops.RHS, llvm::Type::getInt64Ty(VMContext)),
1237 llvm::ConstantInt::get(llvm::Type::getInt8Ty(VMContext), OpID),
1238 llvm::ConstantInt::get(llvm::Type::getInt8Ty(VMContext),
1239 cast<llvm::IntegerType>(opTy)->getBitWidth()));
1241 handlerResult = Builder.CreateTrunc(handlerResult, opTy);
1243 Builder.CreateBr(continueBB);
1245 // Set up the continuation
1246 Builder.SetInsertPoint(continueBB);
1247 // Get the correct result
1248 llvm::PHINode *phi = Builder.CreatePHI(opTy);
1249 phi->reserveOperandSpace(2);
1250 phi->addIncoming(result, initialBB);
1251 phi->addIncoming(handlerResult, overflowBB);
1256 Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) {
1257 if (!Ops.Ty->isAnyPointerType()) {
1258 if (CGF.getContext().getLangOptions().OverflowChecking &&
1259 Ops.Ty->isSignedIntegerType())
1260 return EmitOverflowCheckedBinOp(Ops);
1262 if (Ops.LHS->getType()->isFPOrFPVector())
1263 return Builder.CreateFAdd(Ops.LHS, Ops.RHS, "add");
1265 // Signed integer overflow is undefined behavior.
1266 if (Ops.Ty->isSignedIntegerType())
1267 return Builder.CreateNSWAdd(Ops.LHS, Ops.RHS, "add");
1269 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add");
1272 if (Ops.Ty->isPointerType() &&
1273 Ops.Ty->getAs<PointerType>()->isVariableArrayType()) {
1274 // The amount of the addition needs to account for the VLA size
1275 CGF.ErrorUnsupported(Ops.E, "VLA pointer addition");
1279 const PointerType *PT = Ops.E->getLHS()->getType()->getAs<PointerType>();
1280 const ObjCObjectPointerType *OPT =
1281 Ops.E->getLHS()->getType()->getAs<ObjCObjectPointerType>();
1285 IdxExp = Ops.E->getRHS();
1286 } else { // int + pointer
1287 PT = Ops.E->getRHS()->getType()->getAs<PointerType>();
1288 OPT = Ops.E->getRHS()->getType()->getAs<ObjCObjectPointerType>();
1289 assert((PT || OPT) && "Invalid add expr");
1292 IdxExp = Ops.E->getLHS();
1295 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth();
1296 if (Width < CGF.LLVMPointerWidth) {
1297 // Zero or sign extend the pointer value based on whether the index is
1299 const llvm::Type *IdxType =
1300 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth);
1301 if (IdxExp->getType()->isSignedIntegerType())
1302 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext");
1304 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext");
1306 const QualType ElementType = PT ? PT->getPointeeType() : OPT->getPointeeType();
1307 // Handle interface types, which are not represented with a concrete type.
1308 if (const ObjCInterfaceType *OIT = dyn_cast<ObjCInterfaceType>(ElementType)) {
1309 llvm::Value *InterfaceSize =
1310 llvm::ConstantInt::get(Idx->getType(),
1311 CGF.getContext().getTypeSize(OIT) / 8);
1312 Idx = Builder.CreateMul(Idx, InterfaceSize);
1313 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext);
1314 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty);
1315 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr");
1316 return Builder.CreateBitCast(Res, Ptr->getType());
1319 // Explicitly handle GNU void* and function pointer arithmetic extensions. The
1320 // GNU void* casts amount to no-ops since our void* type is i8*, but this is
1322 if (ElementType->isVoidType() || ElementType->isFunctionType()) {
1323 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext);
1324 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty);
1325 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr");
1326 return Builder.CreateBitCast(Res, Ptr->getType());
1329 return Builder.CreateInBoundsGEP(Ptr, Idx, "add.ptr");
1332 Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) {
1333 if (!isa<llvm::PointerType>(Ops.LHS->getType())) {
1334 if (CGF.getContext().getLangOptions().OverflowChecking
1335 && Ops.Ty->isSignedIntegerType())
1336 return EmitOverflowCheckedBinOp(Ops);
1338 if (Ops.LHS->getType()->isFPOrFPVector())
1339 return Builder.CreateFSub(Ops.LHS, Ops.RHS, "sub");
1340 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub");
1343 if (Ops.E->getLHS()->getType()->isPointerType() &&
1344 Ops.E->getLHS()->getType()->getAs<PointerType>()->isVariableArrayType()) {
1345 // The amount of the addition needs to account for the VLA size for
1347 // The amount of the division needs to account for the VLA size for
1349 CGF.ErrorUnsupported(Ops.E, "VLA pointer subtraction");
1352 const QualType LHSType = Ops.E->getLHS()->getType();
1353 const QualType LHSElementType = LHSType->getPointeeType();
1354 if (!isa<llvm::PointerType>(Ops.RHS->getType())) {
1356 Value *Idx = Ops.RHS;
1357 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth();
1358 if (Width < CGF.LLVMPointerWidth) {
1359 // Zero or sign extend the pointer value based on whether the index is
1361 const llvm::Type *IdxType =
1362 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth);
1363 if (Ops.E->getRHS()->getType()->isSignedIntegerType())
1364 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext");
1366 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext");
1368 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg");
1370 // Handle interface types, which are not represented with a concrete type.
1371 if (const ObjCInterfaceType *OIT =
1372 dyn_cast<ObjCInterfaceType>(LHSElementType)) {
1373 llvm::Value *InterfaceSize =
1374 llvm::ConstantInt::get(Idx->getType(),
1375 CGF.getContext().getTypeSize(OIT) / 8);
1376 Idx = Builder.CreateMul(Idx, InterfaceSize);
1377 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext);
1378 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty);
1379 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "add.ptr");
1380 return Builder.CreateBitCast(Res, Ops.LHS->getType());
1383 // Explicitly handle GNU void* and function pointer arithmetic
1384 // extensions. The GNU void* casts amount to no-ops since our void* type is
1385 // i8*, but this is future proof.
1386 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) {
1387 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext);
1388 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty);
1389 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "sub.ptr");
1390 return Builder.CreateBitCast(Res, Ops.LHS->getType());
1393 return Builder.CreateInBoundsGEP(Ops.LHS, Idx, "sub.ptr");
1395 // pointer - pointer
1396 Value *LHS = Ops.LHS;
1397 Value *RHS = Ops.RHS;
1399 uint64_t ElementSize;
1401 // Handle GCC extension for pointer arithmetic on void* and function pointer
1403 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) {
1406 ElementSize = CGF.getContext().getTypeSize(LHSElementType) / 8;
1409 const llvm::Type *ResultType = ConvertType(Ops.Ty);
1410 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast");
1411 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
1412 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub");
1414 // Optimize out the shift for element size of 1.
1415 if (ElementSize == 1)
1416 return BytesBetween;
1418 // Otherwise, do a full sdiv. This uses the "exact" form of sdiv, since
1419 // pointer difference in C is only defined in the case where both operands
1420 // are pointing to elements of an array.
1421 Value *BytesPerElt = llvm::ConstantInt::get(ResultType, ElementSize);
1422 return Builder.CreateExactSDiv(BytesBetween, BytesPerElt, "sub.ptr.div");
1426 Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) {
1427 // LLVM requires the LHS and RHS to be the same type: promote or truncate the
1428 // RHS to the same size as the LHS.
1429 Value *RHS = Ops.RHS;
1430 if (Ops.LHS->getType() != RHS->getType())
1431 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom");
1433 return Builder.CreateShl(Ops.LHS, RHS, "shl");
1436 Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) {
1437 // LLVM requires the LHS and RHS to be the same type: promote or truncate the
1438 // RHS to the same size as the LHS.
1439 Value *RHS = Ops.RHS;
1440 if (Ops.LHS->getType() != RHS->getType())
1441 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom");
1443 if (Ops.Ty->isUnsignedIntegerType())
1444 return Builder.CreateLShr(Ops.LHS, RHS, "shr");
1445 return Builder.CreateAShr(Ops.LHS, RHS, "shr");
1448 Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc,
1449 unsigned SICmpOpc, unsigned FCmpOpc) {
1450 TestAndClearIgnoreResultAssign();
1452 QualType LHSTy = E->getLHS()->getType();
1453 if (!LHSTy->isAnyComplexType()) {
1454 Value *LHS = Visit(E->getLHS());
1455 Value *RHS = Visit(E->getRHS());
1457 if (LHS->getType()->isFPOrFPVector()) {
1458 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc,
1460 } else if (LHSTy->isSignedIntegerType()) {
1461 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc,
1464 // Unsigned integers and pointers.
1465 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc,
1469 // If this is a vector comparison, sign extend the result to the appropriate
1470 // vector integer type and return it (don't convert to bool).
1471 if (LHSTy->isVectorType())
1472 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext");
1475 // Complex Comparison: can only be an equality comparison.
1476 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS());
1477 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS());
1479 QualType CETy = LHSTy->getAs<ComplexType>()->getElementType();
1481 Value *ResultR, *ResultI;
1482 if (CETy->isRealFloatingType()) {
1483 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc,
1484 LHS.first, RHS.first, "cmp.r");
1485 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc,
1486 LHS.second, RHS.second, "cmp.i");
1488 // Complex comparisons can only be equality comparisons. As such, signed
1489 // and unsigned opcodes are the same.
1490 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc,
1491 LHS.first, RHS.first, "cmp.r");
1492 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc,
1493 LHS.second, RHS.second, "cmp.i");
1496 if (E->getOpcode() == BinaryOperator::EQ) {
1497 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri");
1499 assert(E->getOpcode() == BinaryOperator::NE &&
1500 "Complex comparison other than == or != ?");
1501 Result = Builder.CreateOr(ResultR, ResultI, "or.ri");
1505 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType());
1508 Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) {
1509 bool Ignore = TestAndClearIgnoreResultAssign();
1511 // __block variables need to have the rhs evaluated first, plus this should
1512 // improve codegen just a little.
1513 Value *RHS = Visit(E->getRHS());
1514 LValue LHS = EmitLValue(E->getLHS());
1516 // Store the value into the LHS. Bit-fields are handled specially
1517 // because the result is altered by the store, i.e., [C99 6.5.16p1]
1518 // 'An assignment expression has the value of the left operand after
1519 // the assignment...'.
1520 if (LHS.isBitfield()) {
1521 if (!LHS.isVolatileQualified()) {
1522 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(),
1526 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType());
1528 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType());
1531 return EmitLoadOfLValue(LHS, E->getType());
1534 Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) {
1535 const llvm::Type *ResTy = ConvertType(E->getType());
1537 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0.
1538 // If we have 1 && X, just emit X without inserting the control flow.
1539 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) {
1540 if (Cond == 1) { // If we have 1 && X, just emit X.
1541 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
1542 // ZExt result to int or bool.
1543 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "land.ext");
1546 // 0 && RHS: If it is safe, just elide the RHS, and return 0/false.
1547 if (!CGF.ContainsLabel(E->getRHS()))
1548 return llvm::Constant::getNullValue(ResTy);
1551 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end");
1552 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs");
1554 // Branch on the LHS first. If it is false, go to the failure (cont) block.
1555 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock);
1557 // Any edges into the ContBlock are now from an (indeterminate number of)
1558 // edges from this first condition. All of these values will be false. Start
1559 // setting up the PHI node in the Cont Block for this.
1560 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext),
1562 PN->reserveOperandSpace(2); // Normal case, two inputs.
1563 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock);
1565 PN->addIncoming(llvm::ConstantInt::getFalse(VMContext), *PI);
1567 CGF.PushConditionalTempDestruction();
1568 CGF.EmitBlock(RHSBlock);
1569 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
1570 CGF.PopConditionalTempDestruction();
1572 // Reaquire the RHS block, as there may be subblocks inserted.
1573 RHSBlock = Builder.GetInsertBlock();
1575 // Emit an unconditional branch from this block to ContBlock. Insert an entry
1576 // into the phi node for the edge with the value of RHSCond.
1577 CGF.EmitBlock(ContBlock);
1578 PN->addIncoming(RHSCond, RHSBlock);
1580 // ZExt result to int.
1581 return Builder.CreateZExtOrBitCast(PN, ResTy, "land.ext");
1584 Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) {
1585 const llvm::Type *ResTy = ConvertType(E->getType());
1587 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1.
1588 // If we have 0 || X, just emit X without inserting the control flow.
1589 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) {
1590 if (Cond == -1) { // If we have 0 || X, just emit X.
1591 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
1592 // ZExt result to int or bool.
1593 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "lor.ext");
1596 // 1 || RHS: If it is safe, just elide the RHS, and return 1/true.
1597 if (!CGF.ContainsLabel(E->getRHS()))
1598 return llvm::ConstantInt::get(ResTy, 1);
1601 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end");
1602 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs");
1604 // Branch on the LHS first. If it is true, go to the success (cont) block.
1605 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock);
1607 // Any edges into the ContBlock are now from an (indeterminate number of)
1608 // edges from this first condition. All of these values will be true. Start
1609 // setting up the PHI node in the Cont Block for this.
1610 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext),
1612 PN->reserveOperandSpace(2); // Normal case, two inputs.
1613 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock);
1615 PN->addIncoming(llvm::ConstantInt::getTrue(VMContext), *PI);
1617 CGF.PushConditionalTempDestruction();
1619 // Emit the RHS condition as a bool value.
1620 CGF.EmitBlock(RHSBlock);
1621 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS());
1623 CGF.PopConditionalTempDestruction();
1625 // Reaquire the RHS block, as there may be subblocks inserted.
1626 RHSBlock = Builder.GetInsertBlock();
1628 // Emit an unconditional branch from this block to ContBlock. Insert an entry
1629 // into the phi node for the edge with the value of RHSCond.
1630 CGF.EmitBlock(ContBlock);
1631 PN->addIncoming(RHSCond, RHSBlock);
1633 // ZExt result to int.
1634 return Builder.CreateZExtOrBitCast(PN, ResTy, "lor.ext");
1637 Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) {
1638 CGF.EmitStmt(E->getLHS());
1639 CGF.EnsureInsertPoint();
1640 return Visit(E->getRHS());
1643 //===----------------------------------------------------------------------===//
1645 //===----------------------------------------------------------------------===//
1647 /// isCheapEnoughToEvaluateUnconditionally - Return true if the specified
1648 /// expression is cheap enough and side-effect-free enough to evaluate
1649 /// unconditionally instead of conditionally. This is used to convert control
1650 /// flow into selects in some cases.
1651 static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E,
1652 CodeGenFunction &CGF) {
1653 if (const ParenExpr *PE = dyn_cast<ParenExpr>(E))
1654 return isCheapEnoughToEvaluateUnconditionally(PE->getSubExpr(), CGF);
1656 // TODO: Allow anything we can constant fold to an integer or fp constant.
1657 if (isa<IntegerLiteral>(E) || isa<CharacterLiteral>(E) ||
1658 isa<FloatingLiteral>(E))
1661 // Non-volatile automatic variables too, to get "cond ? X : Y" where
1662 // X and Y are local variables.
1663 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
1664 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl()))
1665 if (VD->hasLocalStorage() && !(CGF.getContext()
1666 .getCanonicalType(VD->getType())
1667 .isVolatileQualified()))
1674 Value *ScalarExprEmitter::
1675 VisitConditionalOperator(const ConditionalOperator *E) {
1676 TestAndClearIgnoreResultAssign();
1677 // If the condition constant folds and can be elided, try to avoid emitting
1678 // the condition and the dead arm.
1679 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getCond())){
1680 Expr *Live = E->getLHS(), *Dead = E->getRHS();
1682 std::swap(Live, Dead);
1684 // If the dead side doesn't have labels we need, and if the Live side isn't
1685 // the gnu missing ?: extension (which we could handle, but don't bother
1686 // to), just emit the Live part.
1687 if ((!Dead || !CGF.ContainsLabel(Dead)) && // No labels in dead part
1688 Live) // Live part isn't missing.
1693 // If this is a really simple expression (like x ? 4 : 5), emit this as a
1694 // select instead of as control flow. We can only do this if it is cheap and
1695 // safe to evaluate the LHS and RHS unconditionally.
1696 if (E->getLHS() && isCheapEnoughToEvaluateUnconditionally(E->getLHS(),
1698 isCheapEnoughToEvaluateUnconditionally(E->getRHS(), CGF)) {
1699 llvm::Value *CondV = CGF.EvaluateExprAsBool(E->getCond());
1700 llvm::Value *LHS = Visit(E->getLHS());
1701 llvm::Value *RHS = Visit(E->getRHS());
1702 return Builder.CreateSelect(CondV, LHS, RHS, "cond");
1706 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true");
1707 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false");
1708 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end");
1711 // If we don't have the GNU missing condition extension, emit a branch on bool
1714 // Otherwise, just use EmitBranchOnBoolExpr to get small and simple code for
1715 // the branch on bool.
1716 CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock);
1718 // Otherwise, for the ?: extension, evaluate the conditional and then
1719 // convert it to bool the hard way. We do this explicitly because we need
1720 // the unconverted value for the missing middle value of the ?:.
1721 CondVal = CGF.EmitScalarExpr(E->getCond());
1723 // In some cases, EmitScalarConversion will delete the "CondVal" expression
1724 // if there are no extra uses (an optimization). Inhibit this by making an
1725 // extra dead use, because we're going to add a use of CondVal later. We
1726 // don't use the builder for this, because we don't want it to get optimized
1727 // away. This leaves dead code, but the ?: extension isn't common.
1728 new llvm::BitCastInst(CondVal, CondVal->getType(), "dummy?:holder",
1729 Builder.GetInsertBlock());
1731 Value *CondBoolVal =
1732 CGF.EmitScalarConversion(CondVal, E->getCond()->getType(),
1733 CGF.getContext().BoolTy);
1734 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock);
1737 CGF.PushConditionalTempDestruction();
1738 CGF.EmitBlock(LHSBlock);
1740 // Handle the GNU extension for missing LHS.
1743 LHS = Visit(E->getLHS());
1744 else // Perform promotions, to handle cases like "short ?: int"
1745 LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType());
1747 CGF.PopConditionalTempDestruction();
1748 LHSBlock = Builder.GetInsertBlock();
1749 CGF.EmitBranch(ContBlock);
1751 CGF.PushConditionalTempDestruction();
1752 CGF.EmitBlock(RHSBlock);
1754 Value *RHS = Visit(E->getRHS());
1755 CGF.PopConditionalTempDestruction();
1756 RHSBlock = Builder.GetInsertBlock();
1757 CGF.EmitBranch(ContBlock);
1759 CGF.EmitBlock(ContBlock);
1762 assert(E->getType()->isVoidType() && "Non-void value should have a value");
1766 // Create a PHI node for the real part.
1767 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond");
1768 PN->reserveOperandSpace(2);
1769 PN->addIncoming(LHS, LHSBlock);
1770 PN->addIncoming(RHS, RHSBlock);
1774 Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) {
1775 return Visit(E->getChosenSubExpr(CGF.getContext()));
1778 Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) {
1779 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr());
1780 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType());
1782 // If EmitVAArg fails, we fall back to the LLVM instruction.
1784 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType()));
1786 // FIXME Volatility.
1787 return Builder.CreateLoad(ArgPtr);
1790 Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *BE) {
1791 return CGF.BuildBlockLiteralTmp(BE);
1794 //===----------------------------------------------------------------------===//
1795 // Entry Point into this File
1796 //===----------------------------------------------------------------------===//
1798 /// EmitScalarExpr - Emit the computation of the specified expression of scalar
1799 /// type, ignoring the result.
1800 Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) {
1801 assert(E && !hasAggregateLLVMType(E->getType()) &&
1802 "Invalid scalar expression to emit");
1804 return ScalarExprEmitter(*this, IgnoreResultAssign)
1805 .Visit(const_cast<Expr*>(E));
1808 /// EmitScalarConversion - Emit a conversion from the specified type to the
1809 /// specified destination type, both of which are LLVM scalar types.
1810 Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy,
1812 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) &&
1813 "Invalid scalar expression to emit");
1814 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy);
1817 /// EmitComplexToScalarConversion - Emit a conversion from the specified complex
1818 /// type to the specified destination type, where the destination type is an
1819 /// LLVM scalar type.
1820 Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src,
1823 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) &&
1824 "Invalid complex -> scalar conversion");
1825 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy,
1829 Value *CodeGenFunction::EmitShuffleVector(Value* V1, Value *V2, ...) {
1830 assert(V1->getType() == V2->getType() &&
1831 "Vector operands must be of the same type");
1832 unsigned NumElements =
1833 cast<llvm::VectorType>(V1->getType())->getNumElements();
1838 llvm::SmallVector<llvm::Constant*, 16> Args;
1839 for (unsigned i = 0; i < NumElements; i++) {
1840 int n = va_arg(va, int);
1841 assert(n >= 0 && n < (int)NumElements * 2 &&
1842 "Vector shuffle index out of bounds!");
1843 Args.push_back(llvm::ConstantInt::get(
1844 llvm::Type::getInt32Ty(VMContext), n));
1847 const char *Name = va_arg(va, const char *);
1850 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements);
1852 return Builder.CreateShuffleVector(V1, V2, Mask, Name);
1855 llvm::Value *CodeGenFunction::EmitVector(llvm::Value * const *Vals,
1856 unsigned NumVals, bool isSplat) {
1858 = llvm::UndefValue::get(llvm::VectorType::get(Vals[0]->getType(), NumVals));
1860 for (unsigned i = 0, e = NumVals; i != e; ++i) {
1861 llvm::Value *Val = isSplat ? Vals[0] : Vals[i];
1862 llvm::Value *Idx = llvm::ConstantInt::get(
1863 llvm::Type::getInt32Ty(VMContext), i);
1864 Vec = Builder.CreateInsertElement(Vec, Val, Idx, "tmp");