CGExprScalar.cpp revision b81c786de58ce484230dc04f9a7c78bc48990106
1//===--- CGExprScalar.cpp - Emit LLVM Code for Scalar 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 scalar LLVM types as LLVM code. 11// 12//===----------------------------------------------------------------------===// 13 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/CFG.h" 28#include "llvm/Target/TargetData.h" 29#include <cstdarg> 30 31using namespace clang; 32using namespace CodeGen; 33using llvm::Value; 34 35//===----------------------------------------------------------------------===// 36// Scalar Expression Emitter 37//===----------------------------------------------------------------------===// 38 39struct BinOpInfo { 40 Value *LHS; 41 Value *RHS; 42 QualType Ty; // Computation Type. 43 const BinaryOperator *E; 44}; 45 46namespace { 47class ScalarExprEmitter 48 : public StmtVisitor<ScalarExprEmitter, Value*> { 49 CodeGenFunction &CGF; 50 CGBuilderTy &Builder; 51 bool IgnoreResultAssign; 52 llvm::LLVMContext &VMContext; 53public: 54 55 ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false) 56 : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira), 57 VMContext(cgf.getLLVMContext()) { 58 } 59 60 //===--------------------------------------------------------------------===// 61 // Utilities 62 //===--------------------------------------------------------------------===// 63 64 bool TestAndClearIgnoreResultAssign() { 65 bool I = IgnoreResultAssign; 66 IgnoreResultAssign = false; 67 return I; 68 } 69 70 const llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 71 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 72 73 Value *EmitLoadOfLValue(LValue LV, QualType T) { 74 return CGF.EmitLoadOfLValue(LV, T).getScalarVal(); 75 } 76 77 /// EmitLoadOfLValue - Given an expression with complex type that represents a 78 /// value l-value, this method emits the address of the l-value, then loads 79 /// and returns the result. 80 Value *EmitLoadOfLValue(const Expr *E) { 81 return EmitLoadOfLValue(EmitLValue(E), E->getType()); 82 } 83 84 /// EmitConversionToBool - Convert the specified expression value to a 85 /// boolean (i1) truth value. This is equivalent to "Val != 0". 86 Value *EmitConversionToBool(Value *Src, QualType DstTy); 87 88 /// EmitScalarConversion - Emit a conversion from the specified type to the 89 /// specified destination type, both of which are LLVM scalar types. 90 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 91 92 /// EmitComplexToScalarConversion - Emit a conversion from the specified 93 /// complex type to the specified destination type, where the destination type 94 /// is an LLVM scalar type. 95 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 96 QualType SrcTy, QualType DstTy); 97 98 //===--------------------------------------------------------------------===// 99 // Visitor Methods 100 //===--------------------------------------------------------------------===// 101 102 Value *VisitStmt(Stmt *S) { 103 S->dump(CGF.getContext().getSourceManager()); 104 assert(0 && "Stmt can't have complex result type!"); 105 return 0; 106 } 107 Value *VisitExpr(Expr *S); 108 109 Value *VisitParenExpr(ParenExpr *PE) { return Visit(PE->getSubExpr()); } 110 111 // Leaves. 112 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 113 return llvm::ConstantInt::get(VMContext, E->getValue()); 114 } 115 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 116 return llvm::ConstantFP::get(VMContext, E->getValue()); 117 } 118 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 119 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 120 } 121 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 122 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 123 } 124 Value *VisitCXXZeroInitValueExpr(const CXXZeroInitValueExpr *E) { 125 return llvm::Constant::getNullValue(ConvertType(E->getType())); 126 } 127 Value *VisitGNUNullExpr(const GNUNullExpr *E) { 128 return llvm::Constant::getNullValue(ConvertType(E->getType())); 129 } 130 Value *VisitTypesCompatibleExpr(const TypesCompatibleExpr *E) { 131 return llvm::ConstantInt::get(ConvertType(E->getType()), 132 CGF.getContext().typesAreCompatible( 133 E->getArgType1(), E->getArgType2())); 134 } 135 Value *VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E); 136 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 137 llvm::Value *V = CGF.GetAddrOfLabel(E->getLabel()); 138 return Builder.CreateBitCast(V, ConvertType(E->getType())); 139 } 140 141 // l-values. 142 Value *VisitDeclRefExpr(DeclRefExpr *E) { 143 Expr::EvalResult Result; 144 if (E->Evaluate(Result, CGF.getContext()) && Result.Val.isInt()) { 145 assert(!Result.HasSideEffects && "Constant declref with side-effect?!"); 146 return llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 147 } 148 return EmitLoadOfLValue(E); 149 } 150 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 151 return CGF.EmitObjCSelectorExpr(E); 152 } 153 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 154 return CGF.EmitObjCProtocolExpr(E); 155 } 156 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 157 return EmitLoadOfLValue(E); 158 } 159 Value *VisitObjCPropertyRefExpr(ObjCPropertyRefExpr *E) { 160 return EmitLoadOfLValue(E); 161 } 162 Value *VisitObjCImplicitSetterGetterRefExpr( 163 ObjCImplicitSetterGetterRefExpr *E) { 164 return EmitLoadOfLValue(E); 165 } 166 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { 167 return CGF.EmitObjCMessageExpr(E).getScalarVal(); 168 } 169 170 Value *VisitObjCIsaExpr(ObjCIsaExpr *E) { 171 LValue LV = CGF.EmitObjCIsaExpr(E); 172 Value *V = CGF.EmitLoadOfLValue(LV, E->getType()).getScalarVal(); 173 return V; 174 } 175 176 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 177 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 178 Value *VisitMemberExpr(MemberExpr *E); 179 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 180 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 181 return EmitLoadOfLValue(E); 182 } 183 Value *VisitStringLiteral(Expr *E) { return EmitLValue(E).getAddress(); } 184 Value *VisitObjCEncodeExpr(const ObjCEncodeExpr *E) { 185 return EmitLValue(E).getAddress(); 186 } 187 188 Value *VisitPredefinedExpr(Expr *E) { return EmitLValue(E).getAddress(); } 189 190 Value *VisitInitListExpr(InitListExpr *E); 191 192 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { 193 return llvm::Constant::getNullValue(ConvertType(E->getType())); 194 } 195 Value *VisitCastExpr(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()); 199 200 return EmitCastExpr(E); 201 } 202 Value *EmitCastExpr(CastExpr *E); 203 204 Value *VisitCallExpr(const CallExpr *E) { 205 if (E->getCallReturnType()->isReferenceType()) 206 return EmitLoadOfLValue(E); 207 208 return CGF.EmitCallExpr(E).getScalarVal(); 209 } 210 211 Value *VisitStmtExpr(const StmtExpr *E); 212 213 Value *VisitBlockDeclRefExpr(const BlockDeclRefExpr *E); 214 215 // Unary Operators. 216 Value *VisitPrePostIncDec(const UnaryOperator *E, bool isInc, bool isPre); 217 Value *VisitUnaryPostDec(const UnaryOperator *E) { 218 return VisitPrePostIncDec(E, false, false); 219 } 220 Value *VisitUnaryPostInc(const UnaryOperator *E) { 221 return VisitPrePostIncDec(E, true, false); 222 } 223 Value *VisitUnaryPreDec(const UnaryOperator *E) { 224 return VisitPrePostIncDec(E, false, true); 225 } 226 Value *VisitUnaryPreInc(const UnaryOperator *E) { 227 return VisitPrePostIncDec(E, true, true); 228 } 229 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 230 return EmitLValue(E->getSubExpr()).getAddress(); 231 } 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()); 237 } 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()); 245 } 246 Value *VisitUnaryOffsetOf(const UnaryOperator *E); 247 248 // C++ 249 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 250 return Visit(DAE->getExpr()); 251 } 252 Value *VisitCXXThisExpr(CXXThisExpr *TE) { 253 return CGF.LoadCXXThis(); 254 } 255 256 Value *VisitCXXExprWithTemporaries(CXXExprWithTemporaries *E) { 257 return CGF.EmitCXXExprWithTemporaries(E).getScalarVal(); 258 } 259 Value *VisitCXXNewExpr(const CXXNewExpr *E) { 260 return CGF.EmitCXXNewExpr(E); 261 } 262 Value *VisitCXXDeleteExpr(const CXXDeleteExpr *E) { 263 CGF.EmitCXXDeleteExpr(E); 264 return 0; 265 } 266 Value *VisitUnaryTypeTraitExpr(const UnaryTypeTraitExpr *E) { 267 return llvm::ConstantInt::get(Builder.getInt1Ty(), 268 E->EvaluateTrait(CGF.getContext())); 269 } 270 271 Value *VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) { 272 // C++ [expr.pseudo]p1: 273 // The result shall only be used as the operand for the function call 274 // operator (), and the result of such a call has type void. The only 275 // effect is the evaluation of the postfix-expression before the dot or 276 // arrow. 277 CGF.EmitScalarExpr(E->getBase()); 278 return 0; 279 } 280 281 Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) { 282 return llvm::Constant::getNullValue(ConvertType(E->getType())); 283 } 284 285 Value *VisitCXXThrowExpr(const CXXThrowExpr *E) { 286 CGF.EmitCXXThrowExpr(E); 287 return 0; 288 } 289 290 // Binary Operators. 291 Value *EmitMul(const BinOpInfo &Ops) { 292 if (CGF.getContext().getLangOptions().OverflowChecking 293 && Ops.Ty->isSignedIntegerType()) 294 return EmitOverflowCheckedBinOp(Ops); 295 if (Ops.LHS->getType()->isFPOrFPVector()) 296 return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul"); 297 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 298 } 299 /// Create a binary op that checks for overflow. 300 /// Currently only supports +, - and *. 301 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops); 302 Value *EmitDiv(const BinOpInfo &Ops); 303 Value *EmitRem(const BinOpInfo &Ops); 304 Value *EmitAdd(const BinOpInfo &Ops); 305 Value *EmitSub(const BinOpInfo &Ops); 306 Value *EmitShl(const BinOpInfo &Ops); 307 Value *EmitShr(const BinOpInfo &Ops); 308 Value *EmitAnd(const BinOpInfo &Ops) { 309 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 310 } 311 Value *EmitXor(const BinOpInfo &Ops) { 312 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 313 } 314 Value *EmitOr (const BinOpInfo &Ops) { 315 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 316 } 317 318 BinOpInfo EmitBinOps(const BinaryOperator *E); 319 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 320 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 321 322 // Binary operators and binary compound assignment operators. 323#define HANDLEBINOP(OP) \ 324 Value *VisitBin ## OP(const BinaryOperator *E) { \ 325 return Emit ## OP(EmitBinOps(E)); \ 326 } \ 327 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 328 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 329 } 330 HANDLEBINOP(Mul); 331 HANDLEBINOP(Div); 332 HANDLEBINOP(Rem); 333 HANDLEBINOP(Add); 334 HANDLEBINOP(Sub); 335 HANDLEBINOP(Shl); 336 HANDLEBINOP(Shr); 337 HANDLEBINOP(And); 338 HANDLEBINOP(Xor); 339 HANDLEBINOP(Or); 340#undef HANDLEBINOP 341 342 // Comparisons. 343 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 344 unsigned SICmpOpc, unsigned FCmpOpc); 345#define VISITCOMP(CODE, UI, SI, FP) \ 346 Value *VisitBin##CODE(const BinaryOperator *E) { \ 347 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 348 llvm::FCmpInst::FP); } 349 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT); 350 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT); 351 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE); 352 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE); 353 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ); 354 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE); 355#undef VISITCOMP 356 357 Value *VisitBinAssign (const BinaryOperator *E); 358 359 Value *VisitBinLAnd (const BinaryOperator *E); 360 Value *VisitBinLOr (const BinaryOperator *E); 361 Value *VisitBinComma (const BinaryOperator *E); 362 363 Value *VisitBinPtrMemD(const Expr *E) { return EmitLoadOfLValue(E); } 364 Value *VisitBinPtrMemI(const Expr *E) { return EmitLoadOfLValue(E); } 365 366 // Other Operators. 367 Value *VisitBlockExpr(const BlockExpr *BE); 368 Value *VisitConditionalOperator(const ConditionalOperator *CO); 369 Value *VisitChooseExpr(ChooseExpr *CE); 370 Value *VisitVAArgExpr(VAArgExpr *VE); 371 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 372 return CGF.EmitObjCStringLiteral(E); 373 } 374}; 375} // end anonymous namespace. 376 377//===----------------------------------------------------------------------===// 378// Utilities 379//===----------------------------------------------------------------------===// 380 381/// EmitConversionToBool - Convert the specified expression value to a 382/// boolean (i1) truth value. This is equivalent to "Val != 0". 383Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 384 assert(SrcType.isCanonical() && "EmitScalarConversion strips typedefs"); 385 386 if (SrcType->isRealFloatingType()) { 387 // Compare against 0.0 for fp scalars. 388 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 389 return Builder.CreateFCmpUNE(Src, Zero, "tobool"); 390 } 391 392 if (SrcType->isMemberPointerType()) { 393 // FIXME: This is ABI specific. 394 395 // Compare against -1. 396 llvm::Value *NegativeOne = llvm::Constant::getAllOnesValue(Src->getType()); 397 return Builder.CreateICmpNE(Src, NegativeOne, "tobool"); 398 } 399 400 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 401 "Unknown scalar type to convert"); 402 403 // Because of the type rules of C, we often end up computing a logical value, 404 // then zero extending it to int, then wanting it as a logical value again. 405 // Optimize this common case. 406 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Src)) { 407 if (ZI->getOperand(0)->getType() == 408 llvm::Type::getInt1Ty(CGF.getLLVMContext())) { 409 Value *Result = ZI->getOperand(0); 410 // If there aren't any more uses, zap the instruction to save space. 411 // Note that there can be more uses, for example if this 412 // is the result of an assignment. 413 if (ZI->use_empty()) 414 ZI->eraseFromParent(); 415 return Result; 416 } 417 } 418 419 // Compare against an integer or pointer null. 420 llvm::Value *Zero = llvm::Constant::getNullValue(Src->getType()); 421 return Builder.CreateICmpNE(Src, Zero, "tobool"); 422} 423 424/// EmitScalarConversion - Emit a conversion from the specified type to the 425/// specified destination type, both of which are LLVM scalar types. 426Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 427 QualType DstType) { 428 SrcType = CGF.getContext().getCanonicalType(SrcType); 429 DstType = CGF.getContext().getCanonicalType(DstType); 430 if (SrcType == DstType) return Src; 431 432 if (DstType->isVoidType()) return 0; 433 434 llvm::LLVMContext &VMContext = CGF.getLLVMContext(); 435 436 // Handle conversions to bool first, they are special: comparisons against 0. 437 if (DstType->isBooleanType()) 438 return EmitConversionToBool(Src, SrcType); 439 440 const llvm::Type *DstTy = ConvertType(DstType); 441 442 // Ignore conversions like int -> uint. 443 if (Src->getType() == DstTy) 444 return Src; 445 446 // Handle pointer conversions next: pointers can only be converted to/from 447 // other pointers and integers. Check for pointer types in terms of LLVM, as 448 // some native types (like Obj-C id) may map to a pointer type. 449 if (isa<llvm::PointerType>(DstTy)) { 450 // The source value may be an integer, or a pointer. 451 if (isa<llvm::PointerType>(Src->getType())) 452 return Builder.CreateBitCast(Src, DstTy, "conv"); 453 454 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 455 // First, convert to the correct width so that we control the kind of 456 // extension. 457 const llvm::Type *MiddleTy = 458 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth); 459 bool InputSigned = SrcType->isSignedIntegerType(); 460 llvm::Value* IntResult = 461 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 462 // Then, cast to pointer. 463 return Builder.CreateIntToPtr(IntResult, DstTy, "conv"); 464 } 465 466 if (isa<llvm::PointerType>(Src->getType())) { 467 // Must be an ptr to int cast. 468 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 469 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 470 } 471 472 // A scalar can be splatted to an extended vector of the same element type 473 if (DstType->isExtVectorType() && !SrcType->isVectorType()) { 474 // Cast the scalar to element type 475 QualType EltTy = DstType->getAs<ExtVectorType>()->getElementType(); 476 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy); 477 478 // Insert the element in element zero of an undef vector 479 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 480 llvm::Value *Idx = 481 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 0); 482 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 483 484 // Splat the element across to all elements 485 llvm::SmallVector<llvm::Constant*, 16> Args; 486 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 487 for (unsigned i = 0; i < NumElements; i++) 488 Args.push_back(llvm::ConstantInt::get( 489 llvm::Type::getInt32Ty(VMContext), 0)); 490 491 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 492 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 493 return Yay; 494 } 495 496 // Allow bitcast from vector to integer/fp of the same size. 497 if (isa<llvm::VectorType>(Src->getType()) || 498 isa<llvm::VectorType>(DstTy)) 499 return Builder.CreateBitCast(Src, DstTy, "conv"); 500 501 // Finally, we have the arithmetic types: real int/float. 502 if (isa<llvm::IntegerType>(Src->getType())) { 503 bool InputSigned = SrcType->isSignedIntegerType(); 504 if (isa<llvm::IntegerType>(DstTy)) 505 return Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 506 else if (InputSigned) 507 return Builder.CreateSIToFP(Src, DstTy, "conv"); 508 else 509 return Builder.CreateUIToFP(Src, DstTy, "conv"); 510 } 511 512 assert(Src->getType()->isFloatingPoint() && "Unknown real conversion"); 513 if (isa<llvm::IntegerType>(DstTy)) { 514 if (DstType->isSignedIntegerType()) 515 return Builder.CreateFPToSI(Src, DstTy, "conv"); 516 else 517 return Builder.CreateFPToUI(Src, DstTy, "conv"); 518 } 519 520 assert(DstTy->isFloatingPoint() && "Unknown real conversion"); 521 if (DstTy->getTypeID() < Src->getType()->getTypeID()) 522 return Builder.CreateFPTrunc(Src, DstTy, "conv"); 523 else 524 return Builder.CreateFPExt(Src, DstTy, "conv"); 525} 526 527/// EmitComplexToScalarConversion - Emit a conversion from the specified complex 528/// type to the specified destination type, where the destination type is an 529/// LLVM scalar type. 530Value *ScalarExprEmitter:: 531EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 532 QualType SrcTy, QualType DstTy) { 533 // Get the source element type. 534 SrcTy = SrcTy->getAs<ComplexType>()->getElementType(); 535 536 // Handle conversions to bool first, they are special: comparisons against 0. 537 if (DstTy->isBooleanType()) { 538 // Complex != 0 -> (Real != 0) | (Imag != 0) 539 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 540 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 541 return Builder.CreateOr(Src.first, Src.second, "tobool"); 542 } 543 544 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 545 // the imaginary part of the complex value is discarded and the value of the 546 // real part is converted according to the conversion rules for the 547 // corresponding real type. 548 return EmitScalarConversion(Src.first, SrcTy, DstTy); 549} 550 551 552//===----------------------------------------------------------------------===// 553// Visitor Methods 554//===----------------------------------------------------------------------===// 555 556Value *ScalarExprEmitter::VisitExpr(Expr *E) { 557 CGF.ErrorUnsupported(E, "scalar expression"); 558 if (E->getType()->isVoidType()) 559 return 0; 560 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 561} 562 563Value *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)))); 567 } 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"); 572} 573Value *ScalarExprEmitter::VisitMemberExpr(MemberExpr *E) { 574 Expr::EvalResult Result; 575 if (E->Evaluate(Result, CGF.getContext()) && Result.Val.isInt()) { 576 if (E->isArrow()) 577 CGF.EmitScalarExpr(E->getBase()); 578 else 579 EmitLValue(E->getBase()); 580 return llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 581 } 582 return EmitLoadOfLValue(E); 583} 584 585Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 586 TestAndClearIgnoreResultAssign(); 587 588 // Emit subscript expressions in rvalue context's. For most cases, this just 589 // loads the lvalue formed by the subscript expr. However, we have to be 590 // careful, because the base of a vector subscript is occasionally an rvalue, 591 // so we can't get it as an lvalue. 592 if (!E->getBase()->getType()->isVectorType()) 593 return EmitLoadOfLValue(E); 594 595 // Handle the vector case. The base must be a vector, the index must be an 596 // integer value. 597 Value *Base = Visit(E->getBase()); 598 Value *Idx = Visit(E->getIdx()); 599 bool IdxSigned = E->getIdx()->getType()->isSignedIntegerType(); 600 Idx = Builder.CreateIntCast(Idx, 601 llvm::Type::getInt32Ty(CGF.getLLVMContext()), 602 IdxSigned, 603 "vecidxcast"); 604 return Builder.CreateExtractElement(Base, Idx, "vecext"); 605} 606 607static llvm::Constant *getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx, 608 unsigned Off, const llvm::Type *I32Ty) { 609 int MV = SVI->getMaskValue(Idx); 610 if (MV == -1) 611 return llvm::UndefValue::get(I32Ty); 612 return llvm::ConstantInt::get(I32Ty, Off+MV); 613} 614 615Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) { 616 bool Ignore = TestAndClearIgnoreResultAssign(); 617 (void)Ignore; 618 assert (Ignore == false && "init list ignored"); 619 unsigned NumInitElements = E->getNumInits(); 620 621 if (E->hadArrayRangeDesignator()) 622 CGF.ErrorUnsupported(E, "GNU array range designator extension"); 623 624 const llvm::VectorType *VType = 625 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 626 627 // We have a scalar in braces. Just use the first element. 628 if (!VType) 629 return Visit(E->getInit(0)); 630 631 unsigned ResElts = VType->getNumElements(); 632 const llvm::Type *I32Ty = llvm::Type::getInt32Ty(CGF.getLLVMContext()); 633 634 // Loop over initializers collecting the Value for each, and remembering 635 // whether the source was swizzle (ExtVectorElementExpr). This will allow 636 // us to fold the shuffle for the swizzle into the shuffle for the vector 637 // initializer, since LLVM optimizers generally do not want to touch 638 // shuffles. 639 unsigned CurIdx = 0; 640 bool VIsUndefShuffle = false; 641 llvm::Value *V = llvm::UndefValue::get(VType); 642 for (unsigned i = 0; i != NumInitElements; ++i) { 643 Expr *IE = E->getInit(i); 644 Value *Init = Visit(IE); 645 llvm::SmallVector<llvm::Constant*, 16> Args; 646 647 const llvm::VectorType *VVT = dyn_cast<llvm::VectorType>(Init->getType()); 648 649 // Handle scalar elements. If the scalar initializer is actually one 650 // element of a different vector of the same width, use shuffle instead of 651 // extract+insert. 652 if (!VVT) { 653 if (isa<ExtVectorElementExpr>(IE)) { 654 llvm::ExtractElementInst *EI = cast<llvm::ExtractElementInst>(Init); 655 656 if (EI->getVectorOperandType()->getNumElements() == ResElts) { 657 llvm::ConstantInt *C = cast<llvm::ConstantInt>(EI->getIndexOperand()); 658 Value *LHS = 0, *RHS = 0; 659 if (CurIdx == 0) { 660 // insert into undef -> shuffle (src, undef) 661 Args.push_back(C); 662 for (unsigned j = 1; j != ResElts; ++j) 663 Args.push_back(llvm::UndefValue::get(I32Ty)); 664 665 LHS = EI->getVectorOperand(); 666 RHS = V; 667 VIsUndefShuffle = true; 668 } else if (VIsUndefShuffle) { 669 // insert into undefshuffle && size match -> shuffle (v, src) 670 llvm::ShuffleVectorInst *SVV = cast<llvm::ShuffleVectorInst>(V); 671 for (unsigned j = 0; j != CurIdx; ++j) 672 Args.push_back(getMaskElt(SVV, j, 0, I32Ty)); 673 Args.push_back(llvm::ConstantInt::get(I32Ty, 674 ResElts + C->getZExtValue())); 675 for (unsigned j = CurIdx + 1; j != ResElts; ++j) 676 Args.push_back(llvm::UndefValue::get(I32Ty)); 677 678 LHS = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 679 RHS = EI->getVectorOperand(); 680 VIsUndefShuffle = false; 681 } 682 if (!Args.empty()) { 683 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts); 684 V = Builder.CreateShuffleVector(LHS, RHS, Mask); 685 ++CurIdx; 686 continue; 687 } 688 } 689 } 690 Value *Idx = llvm::ConstantInt::get(I32Ty, CurIdx); 691 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit"); 692 VIsUndefShuffle = false; 693 ++CurIdx; 694 continue; 695 } 696 697 unsigned InitElts = VVT->getNumElements(); 698 699 // If the initializer is an ExtVecEltExpr (a swizzle), and the swizzle's 700 // input is the same width as the vector being constructed, generate an 701 // optimized shuffle of the swizzle input into the result. 702 unsigned Offset = (CurIdx == 0) ? 0 : ResElts; 703 if (isa<ExtVectorElementExpr>(IE)) { 704 llvm::ShuffleVectorInst *SVI = cast<llvm::ShuffleVectorInst>(Init); 705 Value *SVOp = SVI->getOperand(0); 706 const llvm::VectorType *OpTy = cast<llvm::VectorType>(SVOp->getType()); 707 708 if (OpTy->getNumElements() == ResElts) { 709 for (unsigned j = 0; j != CurIdx; ++j) { 710 // If the current vector initializer is a shuffle with undef, merge 711 // this shuffle directly into it. 712 if (VIsUndefShuffle) { 713 Args.push_back(getMaskElt(cast<llvm::ShuffleVectorInst>(V), j, 0, 714 I32Ty)); 715 } else { 716 Args.push_back(llvm::ConstantInt::get(I32Ty, j)); 717 } 718 } 719 for (unsigned j = 0, je = InitElts; j != je; ++j) 720 Args.push_back(getMaskElt(SVI, j, Offset, I32Ty)); 721 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j) 722 Args.push_back(llvm::UndefValue::get(I32Ty)); 723 724 if (VIsUndefShuffle) 725 V = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 726 727 Init = SVOp; 728 } 729 } 730 731 // Extend init to result vector length, and then shuffle its contribution 732 // to the vector initializer into V. 733 if (Args.empty()) { 734 for (unsigned j = 0; j != InitElts; ++j) 735 Args.push_back(llvm::ConstantInt::get(I32Ty, j)); 736 for (unsigned j = InitElts; j != ResElts; ++j) 737 Args.push_back(llvm::UndefValue::get(I32Ty)); 738 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts); 739 Init = Builder.CreateShuffleVector(Init, llvm::UndefValue::get(VVT), 740 Mask, "vext"); 741 742 Args.clear(); 743 for (unsigned j = 0; j != CurIdx; ++j) 744 Args.push_back(llvm::ConstantInt::get(I32Ty, j)); 745 for (unsigned j = 0; j != InitElts; ++j) 746 Args.push_back(llvm::ConstantInt::get(I32Ty, j+Offset)); 747 for (unsigned j = CurIdx + InitElts; j != ResElts; ++j) 748 Args.push_back(llvm::UndefValue::get(I32Ty)); 749 } 750 751 // If V is undef, make sure it ends up on the RHS of the shuffle to aid 752 // merging subsequent shuffles into this one. 753 if (CurIdx == 0) 754 std::swap(V, Init); 755 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], ResElts); 756 V = Builder.CreateShuffleVector(V, Init, Mask, "vecinit"); 757 VIsUndefShuffle = isa<llvm::UndefValue>(Init); 758 CurIdx += InitElts; 759 } 760 761 // FIXME: evaluate codegen vs. shuffling against constant null vector. 762 // Emit remaining default initializers. 763 const llvm::Type *EltTy = VType->getElementType(); 764 765 // Emit remaining default initializers 766 for (/* Do not initialize i*/; CurIdx < ResElts; ++CurIdx) { 767 Value *Idx = llvm::ConstantInt::get(I32Ty, CurIdx); 768 llvm::Value *Init = llvm::Constant::getNullValue(EltTy); 769 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit"); 770 } 771 return V; 772} 773 774static bool ShouldNullCheckClassCastValue(const CastExpr *CE) { 775 const Expr *E = CE->getSubExpr(); 776 777 if (isa<CXXThisExpr>(E)) { 778 // We always assume that 'this' is never null. 779 return false; 780 } 781 782 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(CE)) { 783 // And that lvalue casts are never null. 784 if (ICE->isLvalueCast()) 785 return false; 786 } 787 788 return true; 789} 790 791// VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 792// have to handle a more broad range of conversions than explicit casts, as they 793// handle things like function to ptr-to-function decay etc. 794Value *ScalarExprEmitter::EmitCastExpr(CastExpr *CE) { 795 Expr *E = CE->getSubExpr(); 796 QualType DestTy = CE->getType(); 797 CastExpr::CastKind Kind = CE->getCastKind(); 798 799 if (!DestTy->isVoidType()) 800 TestAndClearIgnoreResultAssign(); 801 802 // Since almost all cast kinds apply to scalars, this switch doesn't have 803 // a default case, so the compiler will warn on a missing case. The cases 804 // are in the same order as in the CastKind enum. 805 switch (Kind) { 806 case CastExpr::CK_Unknown: 807 // FIXME: All casts should have a known kind! 808 //assert(0 && "Unknown cast kind!"); 809 break; 810 811 case CastExpr::CK_AnyPointerToObjCPointerCast: 812 case CastExpr::CK_BitCast: { 813 Value *Src = Visit(const_cast<Expr*>(E)); 814 return Builder.CreateBitCast(Src, ConvertType(DestTy)); 815 } 816 case CastExpr::CK_NoOp: 817 return Visit(const_cast<Expr*>(E)); 818 819 case CastExpr::CK_BaseToDerived: { 820 const CXXRecordDecl *BaseClassDecl = 821 E->getType()->getCXXRecordDeclForPointerType(); 822 const CXXRecordDecl *DerivedClassDecl = 823 DestTy->getCXXRecordDeclForPointerType(); 824 825 Value *Src = Visit(const_cast<Expr*>(E)); 826 827 bool NullCheckValue = ShouldNullCheckClassCastValue(CE); 828 return CGF.GetAddressOfDerivedClass(Src, BaseClassDecl, DerivedClassDecl, 829 NullCheckValue); 830 } 831 case CastExpr::CK_DerivedToBase: { 832 const RecordType *DerivedClassTy = 833 E->getType()->getAs<PointerType>()->getPointeeType()->getAs<RecordType>(); 834 CXXRecordDecl *DerivedClassDecl = 835 cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 836 837 const RecordType *BaseClassTy = 838 DestTy->getAs<PointerType>()->getPointeeType()->getAs<RecordType>(); 839 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseClassTy->getDecl()); 840 841 Value *Src = Visit(const_cast<Expr*>(E)); 842 843 bool NullCheckValue = ShouldNullCheckClassCastValue(CE); 844 return CGF.GetAddressOfBaseClass(Src, DerivedClassDecl, BaseClassDecl, 845 NullCheckValue); 846 } 847 case CastExpr::CK_Dynamic: { 848 Value *V = Visit(const_cast<Expr*>(E)); 849 const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(CE); 850 return CGF.EmitDynamicCast(V, DCE); 851 } 852 case CastExpr::CK_ToUnion: 853 assert(0 && "Should be unreachable!"); 854 break; 855 856 case CastExpr::CK_ArrayToPointerDecay: { 857 assert(E->getType()->isArrayType() && 858 "Array to pointer decay must have array source type!"); 859 860 Value *V = EmitLValue(E).getAddress(); // Bitfields can't be arrays. 861 862 // Note that VLA pointers are always decayed, so we don't need to do 863 // anything here. 864 if (!E->getType()->isVariableArrayType()) { 865 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer"); 866 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 867 ->getElementType()) && 868 "Expected pointer to array"); 869 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 870 } 871 872 return V; 873 } 874 case CastExpr::CK_FunctionToPointerDecay: 875 return EmitLValue(E).getAddress(); 876 877 case CastExpr::CK_NullToMemberPointer: 878 return CGF.CGM.EmitNullConstant(DestTy); 879 880 case CastExpr::CK_BaseToDerivedMemberPointer: 881 case CastExpr::CK_DerivedToBaseMemberPointer: { 882 Value *Src = Visit(E); 883 884 // See if we need to adjust the pointer. 885 const CXXRecordDecl *BaseDecl = 886 cast<CXXRecordDecl>(E->getType()->getAs<MemberPointerType>()-> 887 getClass()->getAs<RecordType>()->getDecl()); 888 const CXXRecordDecl *DerivedDecl = 889 cast<CXXRecordDecl>(CE->getType()->getAs<MemberPointerType>()-> 890 getClass()->getAs<RecordType>()->getDecl()); 891 if (CE->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer) 892 std::swap(DerivedDecl, BaseDecl); 893 894 llvm::Constant *Adj = CGF.CGM.GetCXXBaseClassOffset(DerivedDecl, BaseDecl); 895 if (Adj) { 896 if (CE->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer) 897 Src = Builder.CreateSub(Src, Adj, "adj"); 898 else 899 Src = Builder.CreateAdd(Src, Adj, "adj"); 900 } 901 return Src; 902 } 903 904 case CastExpr::CK_UserDefinedConversion: 905 case CastExpr::CK_ConstructorConversion: 906 assert(0 && "Should be unreachable!"); 907 break; 908 909 case CastExpr::CK_IntegralToPointer: { 910 Value *Src = Visit(const_cast<Expr*>(E)); 911 912 // First, convert to the correct width so that we control the kind of 913 // extension. 914 const llvm::Type *MiddleTy = 915 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth); 916 bool InputSigned = E->getType()->isSignedIntegerType(); 917 llvm::Value* IntResult = 918 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 919 920 return Builder.CreateIntToPtr(IntResult, ConvertType(DestTy)); 921 } 922 case CastExpr::CK_PointerToIntegral: { 923 Value *Src = Visit(const_cast<Expr*>(E)); 924 return Builder.CreatePtrToInt(Src, ConvertType(DestTy)); 925 } 926 case CastExpr::CK_ToVoid: { 927 CGF.EmitAnyExpr(E, 0, false, true); 928 return 0; 929 } 930 case CastExpr::CK_VectorSplat: { 931 const llvm::Type *DstTy = ConvertType(DestTy); 932 Value *Elt = Visit(const_cast<Expr*>(E)); 933 934 // Insert the element in element zero of an undef vector 935 llvm::Value *UnV = llvm::UndefValue::get(DstTy); 936 llvm::Value *Idx = 937 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), 0); 938 UnV = Builder.CreateInsertElement(UnV, Elt, Idx, "tmp"); 939 940 // Splat the element across to all elements 941 llvm::SmallVector<llvm::Constant*, 16> Args; 942 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 943 for (unsigned i = 0; i < NumElements; i++) 944 Args.push_back(llvm::ConstantInt::get( 945 llvm::Type::getInt32Ty(VMContext), 0)); 946 947 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 948 llvm::Value *Yay = Builder.CreateShuffleVector(UnV, UnV, Mask, "splat"); 949 return Yay; 950 } 951 case CastExpr::CK_IntegralCast: 952 case CastExpr::CK_IntegralToFloating: 953 case CastExpr::CK_FloatingToIntegral: 954 case CastExpr::CK_FloatingCast: 955 return EmitScalarConversion(Visit(E), E->getType(), DestTy); 956 957 case CastExpr::CK_MemberPointerToBoolean: { 958 const MemberPointerType* T = E->getType()->getAs<MemberPointerType>(); 959 960 if (T->getPointeeType()->isFunctionType()) { 961 // We have a member function pointer. 962 llvm::Value *Ptr = CGF.CreateTempAlloca(ConvertType(E->getType())); 963 964 CGF.EmitAggExpr(E, Ptr, /*VolatileDest=*/false); 965 966 // Get the pointer. 967 llvm::Value *FuncPtr = Builder.CreateStructGEP(Ptr, 0, "src.ptr"); 968 FuncPtr = Builder.CreateLoad(FuncPtr); 969 970 llvm::Value *IsNotNull = 971 Builder.CreateICmpNE(FuncPtr, 972 llvm::Constant::getNullValue(FuncPtr->getType()), 973 "tobool"); 974 975 return IsNotNull; 976 } 977 978 // We have a regular member pointer. 979 Value *Ptr = Visit(const_cast<Expr*>(E)); 980 llvm::Value *IsNotNull = 981 Builder.CreateICmpNE(Ptr, CGF.CGM.EmitNullConstant(E->getType()), 982 "tobool"); 983 return IsNotNull; 984 } 985 } 986 987 // Handle cases where the source is an non-complex type. 988 989 if (!CGF.hasAggregateLLVMType(E->getType())) { 990 Value *Src = Visit(const_cast<Expr*>(E)); 991 992 // Use EmitScalarConversion to perform the conversion. 993 return EmitScalarConversion(Src, E->getType(), DestTy); 994 } 995 996 if (E->getType()->isAnyComplexType()) { 997 // Handle cases where the source is a complex type. 998 bool IgnoreImag = true; 999 bool IgnoreImagAssign = true; 1000 bool IgnoreReal = IgnoreResultAssign; 1001 bool IgnoreRealAssign = IgnoreResultAssign; 1002 if (DestTy->isBooleanType()) 1003 IgnoreImagAssign = IgnoreImag = false; 1004 else if (DestTy->isVoidType()) { 1005 IgnoreReal = IgnoreImag = false; 1006 IgnoreRealAssign = IgnoreImagAssign = true; 1007 } 1008 CodeGenFunction::ComplexPairTy V 1009 = CGF.EmitComplexExpr(E, IgnoreReal, IgnoreImag, IgnoreRealAssign, 1010 IgnoreImagAssign); 1011 return EmitComplexToScalarConversion(V, E->getType(), DestTy); 1012 } 1013 1014 // Okay, this is a cast from an aggregate. It must be a cast to void. Just 1015 // evaluate the result and return. 1016 CGF.EmitAggExpr(E, 0, false, true); 1017 return 0; 1018} 1019 1020Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 1021 return CGF.EmitCompoundStmt(*E->getSubStmt(), 1022 !E->getType()->isVoidType()).getScalarVal(); 1023} 1024 1025Value *ScalarExprEmitter::VisitBlockDeclRefExpr(const BlockDeclRefExpr *E) { 1026 llvm::Value *V = CGF.GetAddrOfBlockDecl(E); 1027 if (E->getType().isObjCGCWeak()) 1028 return CGF.CGM.getObjCRuntime().EmitObjCWeakRead(CGF, V); 1029 return Builder.CreateLoad(V, "tmp"); 1030} 1031 1032//===----------------------------------------------------------------------===// 1033// Unary Operators 1034//===----------------------------------------------------------------------===// 1035 1036Value *ScalarExprEmitter::VisitPrePostIncDec(const UnaryOperator *E, 1037 bool isInc, bool isPre) { 1038 LValue LV = EmitLValue(E->getSubExpr()); 1039 QualType ValTy = E->getSubExpr()->getType(); 1040 Value *InVal = CGF.EmitLoadOfLValue(LV, ValTy).getScalarVal(); 1041 1042 llvm::LLVMContext &VMContext = CGF.getLLVMContext(); 1043 1044 int AmountVal = isInc ? 1 : -1; 1045 1046 if (ValTy->isPointerType() && 1047 ValTy->getAs<PointerType>()->isVariableArrayType()) { 1048 // The amount of the addition/subtraction needs to account for the VLA size 1049 CGF.ErrorUnsupported(E, "VLA pointer inc/dec"); 1050 } 1051 1052 Value *NextVal; 1053 if (const llvm::PointerType *PT = 1054 dyn_cast<llvm::PointerType>(InVal->getType())) { 1055 llvm::Constant *Inc = 1056 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), AmountVal); 1057 if (!isa<llvm::FunctionType>(PT->getElementType())) { 1058 QualType PTEE = ValTy->getPointeeType(); 1059 if (const ObjCInterfaceType *OIT = 1060 dyn_cast<ObjCInterfaceType>(PTEE)) { 1061 // Handle interface types, which are not represented with a concrete type. 1062 int size = CGF.getContext().getTypeSize(OIT) / 8; 1063 if (!isInc) 1064 size = -size; 1065 Inc = llvm::ConstantInt::get(Inc->getType(), size); 1066 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1067 InVal = Builder.CreateBitCast(InVal, i8Ty); 1068 NextVal = Builder.CreateGEP(InVal, Inc, "add.ptr"); 1069 llvm::Value *lhs = LV.getAddress(); 1070 lhs = Builder.CreateBitCast(lhs, llvm::PointerType::getUnqual(i8Ty)); 1071 LV = LValue::MakeAddr(lhs, CGF.MakeQualifiers(ValTy)); 1072 } else 1073 NextVal = Builder.CreateInBoundsGEP(InVal, Inc, "ptrincdec"); 1074 } else { 1075 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1076 NextVal = Builder.CreateBitCast(InVal, i8Ty, "tmp"); 1077 NextVal = Builder.CreateGEP(NextVal, Inc, "ptrincdec"); 1078 NextVal = Builder.CreateBitCast(NextVal, InVal->getType()); 1079 } 1080 } else if (InVal->getType() == llvm::Type::getInt1Ty(VMContext) && isInc) { 1081 // Bool++ is an interesting case, due to promotion rules, we get: 1082 // Bool++ -> Bool = Bool+1 -> Bool = (int)Bool+1 -> 1083 // Bool = ((int)Bool+1) != 0 1084 // An interesting aspect of this is that increment is always true. 1085 // Decrement does not have this property. 1086 NextVal = llvm::ConstantInt::getTrue(VMContext); 1087 } else if (isa<llvm::IntegerType>(InVal->getType())) { 1088 NextVal = llvm::ConstantInt::get(InVal->getType(), AmountVal); 1089 1090 // Signed integer overflow is undefined behavior. 1091 if (ValTy->isSignedIntegerType()) 1092 NextVal = Builder.CreateNSWAdd(InVal, NextVal, isInc ? "inc" : "dec"); 1093 else 1094 NextVal = Builder.CreateAdd(InVal, NextVal, isInc ? "inc" : "dec"); 1095 } else { 1096 // Add the inc/dec to the real part. 1097 if (InVal->getType()->isFloatTy()) 1098 NextVal = 1099 llvm::ConstantFP::get(VMContext, 1100 llvm::APFloat(static_cast<float>(AmountVal))); 1101 else if (InVal->getType()->isDoubleTy()) 1102 NextVal = 1103 llvm::ConstantFP::get(VMContext, 1104 llvm::APFloat(static_cast<double>(AmountVal))); 1105 else { 1106 llvm::APFloat F(static_cast<float>(AmountVal)); 1107 bool ignored; 1108 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, 1109 &ignored); 1110 NextVal = llvm::ConstantFP::get(VMContext, F); 1111 } 1112 NextVal = Builder.CreateFAdd(InVal, NextVal, isInc ? "inc" : "dec"); 1113 } 1114 1115 // Store the updated result through the lvalue. 1116 if (LV.isBitfield()) 1117 CGF.EmitStoreThroughBitfieldLValue(RValue::get(NextVal), LV, ValTy, 1118 &NextVal); 1119 else 1120 CGF.EmitStoreThroughLValue(RValue::get(NextVal), LV, ValTy); 1121 1122 // If this is a postinc, return the value read from memory, otherwise use the 1123 // updated value. 1124 return isPre ? NextVal : InVal; 1125} 1126 1127 1128Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 1129 TestAndClearIgnoreResultAssign(); 1130 Value *Op = Visit(E->getSubExpr()); 1131 if (Op->getType()->isFPOrFPVector()) 1132 return Builder.CreateFNeg(Op, "neg"); 1133 return Builder.CreateNeg(Op, "neg"); 1134} 1135 1136Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 1137 TestAndClearIgnoreResultAssign(); 1138 Value *Op = Visit(E->getSubExpr()); 1139 return Builder.CreateNot(Op, "neg"); 1140} 1141 1142Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 1143 // Compare operand to zero. 1144 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 1145 1146 // Invert value. 1147 // TODO: Could dynamically modify easy computations here. For example, if 1148 // the operand is an icmp ne, turn into icmp eq. 1149 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 1150 1151 // ZExt result to the expr type. 1152 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext"); 1153} 1154 1155/// VisitSizeOfAlignOfExpr - Return the size or alignment of the type of 1156/// argument of the sizeof expression as an integer. 1157Value * 1158ScalarExprEmitter::VisitSizeOfAlignOfExpr(const SizeOfAlignOfExpr *E) { 1159 QualType TypeToSize = E->getTypeOfArgument(); 1160 if (E->isSizeOf()) { 1161 if (const VariableArrayType *VAT = 1162 CGF.getContext().getAsVariableArrayType(TypeToSize)) { 1163 if (E->isArgumentType()) { 1164 // sizeof(type) - make sure to emit the VLA size. 1165 CGF.EmitVLASize(TypeToSize); 1166 } else { 1167 // C99 6.5.3.4p2: If the argument is an expression of type 1168 // VLA, it is evaluated. 1169 CGF.EmitAnyExpr(E->getArgumentExpr()); 1170 } 1171 1172 return CGF.GetVLASize(VAT); 1173 } 1174 } 1175 1176 // If this isn't sizeof(vla), the result must be constant; use the constant 1177 // folding logic so we don't have to duplicate it here. 1178 Expr::EvalResult Result; 1179 E->Evaluate(Result, CGF.getContext()); 1180 return llvm::ConstantInt::get(VMContext, Result.Val.getInt()); 1181} 1182 1183Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 1184 Expr *Op = E->getSubExpr(); 1185 if (Op->getType()->isAnyComplexType()) 1186 return CGF.EmitComplexExpr(Op, false, true, false, true).first; 1187 return Visit(Op); 1188} 1189Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 1190 Expr *Op = E->getSubExpr(); 1191 if (Op->getType()->isAnyComplexType()) 1192 return CGF.EmitComplexExpr(Op, true, false, true, false).second; 1193 1194 // __imag on a scalar returns zero. Emit the subexpr to ensure side 1195 // effects are evaluated, but not the actual value. 1196 if (E->isLvalue(CGF.getContext()) == Expr::LV_Valid) 1197 CGF.EmitLValue(Op); 1198 else 1199 CGF.EmitScalarExpr(Op, true); 1200 return llvm::Constant::getNullValue(ConvertType(E->getType())); 1201} 1202 1203Value *ScalarExprEmitter::VisitUnaryOffsetOf(const UnaryOperator *E) { 1204 Value* ResultAsPtr = EmitLValue(E->getSubExpr()).getAddress(); 1205 const llvm::Type* ResultType = ConvertType(E->getType()); 1206 return Builder.CreatePtrToInt(ResultAsPtr, ResultType, "offsetof"); 1207} 1208 1209//===----------------------------------------------------------------------===// 1210// Binary Operators 1211//===----------------------------------------------------------------------===// 1212 1213BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 1214 TestAndClearIgnoreResultAssign(); 1215 BinOpInfo Result; 1216 Result.LHS = Visit(E->getLHS()); 1217 Result.RHS = Visit(E->getRHS()); 1218 Result.Ty = E->getType(); 1219 Result.E = E; 1220 return Result; 1221} 1222 1223Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 1224 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 1225 bool Ignore = TestAndClearIgnoreResultAssign(); 1226 QualType LHSTy = E->getLHS()->getType(), RHSTy = E->getRHS()->getType(); 1227 1228 BinOpInfo OpInfo; 1229 1230 if (E->getComputationResultType()->isAnyComplexType()) { 1231 // This needs to go through the complex expression emitter, but it's a tad 1232 // complicated to do that... I'm leaving it out for now. (Note that we do 1233 // actually need the imaginary part of the RHS for multiplication and 1234 // division.) 1235 CGF.ErrorUnsupported(E, "complex compound assignment"); 1236 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 1237 } 1238 1239 // Emit the RHS first. __block variables need to have the rhs evaluated 1240 // first, plus this should improve codegen a little. 1241 OpInfo.RHS = Visit(E->getRHS()); 1242 OpInfo.Ty = E->getComputationResultType(); 1243 OpInfo.E = E; 1244 // Load/convert the LHS. 1245 LValue LHSLV = EmitLValue(E->getLHS()); 1246 OpInfo.LHS = EmitLoadOfLValue(LHSLV, LHSTy); 1247 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, 1248 E->getComputationLHSType()); 1249 1250 // Expand the binary operator. 1251 Value *Result = (this->*Func)(OpInfo); 1252 1253 // Convert the result back to the LHS type. 1254 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy); 1255 1256 // Store the result value into the LHS lvalue. Bit-fields are handled 1257 // specially because the result is altered by the store, i.e., [C99 6.5.16p1] 1258 // 'An assignment expression has the value of the left operand after the 1259 // assignment...'. 1260 if (LHSLV.isBitfield()) { 1261 if (!LHSLV.isVolatileQualified()) { 1262 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy, 1263 &Result); 1264 return Result; 1265 } else 1266 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, LHSTy); 1267 } else 1268 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV, LHSTy); 1269 if (Ignore) 1270 return 0; 1271 return EmitLoadOfLValue(LHSLV, E->getType()); 1272} 1273 1274 1275Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 1276 if (Ops.LHS->getType()->isFPOrFPVector()) 1277 return Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 1278 else if (Ops.Ty->isUnsignedIntegerType()) 1279 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 1280 else 1281 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 1282} 1283 1284Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 1285 // Rem in C can't be a floating point type: C99 6.5.5p2. 1286 if (Ops.Ty->isUnsignedIntegerType()) 1287 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 1288 else 1289 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 1290} 1291 1292Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) { 1293 unsigned IID; 1294 unsigned OpID = 0; 1295 1296 switch (Ops.E->getOpcode()) { 1297 case BinaryOperator::Add: 1298 case BinaryOperator::AddAssign: 1299 OpID = 1; 1300 IID = llvm::Intrinsic::sadd_with_overflow; 1301 break; 1302 case BinaryOperator::Sub: 1303 case BinaryOperator::SubAssign: 1304 OpID = 2; 1305 IID = llvm::Intrinsic::ssub_with_overflow; 1306 break; 1307 case BinaryOperator::Mul: 1308 case BinaryOperator::MulAssign: 1309 OpID = 3; 1310 IID = llvm::Intrinsic::smul_with_overflow; 1311 break; 1312 default: 1313 assert(false && "Unsupported operation for overflow detection"); 1314 IID = 0; 1315 } 1316 OpID <<= 1; 1317 OpID |= 1; 1318 1319 const llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty); 1320 1321 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, &opTy, 1); 1322 1323 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS); 1324 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0); 1325 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1); 1326 1327 // Branch in case of overflow. 1328 llvm::BasicBlock *initialBB = Builder.GetInsertBlock(); 1329 llvm::BasicBlock *overflowBB = 1330 CGF.createBasicBlock("overflow", CGF.CurFn); 1331 llvm::BasicBlock *continueBB = 1332 CGF.createBasicBlock("overflow.continue", CGF.CurFn); 1333 1334 Builder.CreateCondBr(overflow, overflowBB, continueBB); 1335 1336 // Handle overflow 1337 1338 Builder.SetInsertPoint(overflowBB); 1339 1340 // Handler is: 1341 // long long *__overflow_handler)(long long a, long long b, char op, 1342 // char width) 1343 std::vector<const llvm::Type*> handerArgTypes; 1344 handerArgTypes.push_back(llvm::Type::getInt64Ty(VMContext)); 1345 handerArgTypes.push_back(llvm::Type::getInt64Ty(VMContext)); 1346 handerArgTypes.push_back(llvm::Type::getInt8Ty(VMContext)); 1347 handerArgTypes.push_back(llvm::Type::getInt8Ty(VMContext)); 1348 llvm::FunctionType *handlerTy = llvm::FunctionType::get( 1349 llvm::Type::getInt64Ty(VMContext), handerArgTypes, false); 1350 llvm::Value *handlerFunction = 1351 CGF.CGM.getModule().getOrInsertGlobal("__overflow_handler", 1352 llvm::PointerType::getUnqual(handlerTy)); 1353 handlerFunction = Builder.CreateLoad(handlerFunction); 1354 1355 llvm::Value *handlerResult = Builder.CreateCall4(handlerFunction, 1356 Builder.CreateSExt(Ops.LHS, llvm::Type::getInt64Ty(VMContext)), 1357 Builder.CreateSExt(Ops.RHS, llvm::Type::getInt64Ty(VMContext)), 1358 llvm::ConstantInt::get(llvm::Type::getInt8Ty(VMContext), OpID), 1359 llvm::ConstantInt::get(llvm::Type::getInt8Ty(VMContext), 1360 cast<llvm::IntegerType>(opTy)->getBitWidth())); 1361 1362 handlerResult = Builder.CreateTrunc(handlerResult, opTy); 1363 1364 Builder.CreateBr(continueBB); 1365 1366 // Set up the continuation 1367 Builder.SetInsertPoint(continueBB); 1368 // Get the correct result 1369 llvm::PHINode *phi = Builder.CreatePHI(opTy); 1370 phi->reserveOperandSpace(2); 1371 phi->addIncoming(result, initialBB); 1372 phi->addIncoming(handlerResult, overflowBB); 1373 1374 return phi; 1375} 1376 1377Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &Ops) { 1378 if (!Ops.Ty->isAnyPointerType()) { 1379 if (CGF.getContext().getLangOptions().OverflowChecking && 1380 Ops.Ty->isSignedIntegerType()) 1381 return EmitOverflowCheckedBinOp(Ops); 1382 1383 if (Ops.LHS->getType()->isFPOrFPVector()) 1384 return Builder.CreateFAdd(Ops.LHS, Ops.RHS, "add"); 1385 1386 // Signed integer overflow is undefined behavior. 1387 if (Ops.Ty->isSignedIntegerType()) 1388 return Builder.CreateNSWAdd(Ops.LHS, Ops.RHS, "add"); 1389 1390 return Builder.CreateAdd(Ops.LHS, Ops.RHS, "add"); 1391 } 1392 1393 if (Ops.Ty->isPointerType() && 1394 Ops.Ty->getAs<PointerType>()->isVariableArrayType()) { 1395 // The amount of the addition needs to account for the VLA size 1396 CGF.ErrorUnsupported(Ops.E, "VLA pointer addition"); 1397 } 1398 Value *Ptr, *Idx; 1399 Expr *IdxExp; 1400 const PointerType *PT = Ops.E->getLHS()->getType()->getAs<PointerType>(); 1401 const ObjCObjectPointerType *OPT = 1402 Ops.E->getLHS()->getType()->getAs<ObjCObjectPointerType>(); 1403 if (PT || OPT) { 1404 Ptr = Ops.LHS; 1405 Idx = Ops.RHS; 1406 IdxExp = Ops.E->getRHS(); 1407 } else { // int + pointer 1408 PT = Ops.E->getRHS()->getType()->getAs<PointerType>(); 1409 OPT = Ops.E->getRHS()->getType()->getAs<ObjCObjectPointerType>(); 1410 assert((PT || OPT) && "Invalid add expr"); 1411 Ptr = Ops.RHS; 1412 Idx = Ops.LHS; 1413 IdxExp = Ops.E->getLHS(); 1414 } 1415 1416 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1417 if (Width < CGF.LLVMPointerWidth) { 1418 // Zero or sign extend the pointer value based on whether the index is 1419 // signed or not. 1420 const llvm::Type *IdxType = 1421 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth); 1422 if (IdxExp->getType()->isSignedIntegerType()) 1423 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1424 else 1425 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1426 } 1427 const QualType ElementType = PT ? PT->getPointeeType() : OPT->getPointeeType(); 1428 // Handle interface types, which are not represented with a concrete type. 1429 if (const ObjCInterfaceType *OIT = dyn_cast<ObjCInterfaceType>(ElementType)) { 1430 llvm::Value *InterfaceSize = 1431 llvm::ConstantInt::get(Idx->getType(), 1432 CGF.getContext().getTypeSize(OIT) / 8); 1433 Idx = Builder.CreateMul(Idx, InterfaceSize); 1434 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1435 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1436 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1437 return Builder.CreateBitCast(Res, Ptr->getType()); 1438 } 1439 1440 // Explicitly handle GNU void* and function pointer arithmetic extensions. The 1441 // GNU void* casts amount to no-ops since our void* type is i8*, but this is 1442 // future proof. 1443 if (ElementType->isVoidType() || ElementType->isFunctionType()) { 1444 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1445 Value *Casted = Builder.CreateBitCast(Ptr, i8Ty); 1446 Value *Res = Builder.CreateGEP(Casted, Idx, "add.ptr"); 1447 return Builder.CreateBitCast(Res, Ptr->getType()); 1448 } 1449 1450 return Builder.CreateInBoundsGEP(Ptr, Idx, "add.ptr"); 1451} 1452 1453Value *ScalarExprEmitter::EmitSub(const BinOpInfo &Ops) { 1454 if (!isa<llvm::PointerType>(Ops.LHS->getType())) { 1455 if (CGF.getContext().getLangOptions().OverflowChecking 1456 && Ops.Ty->isSignedIntegerType()) 1457 return EmitOverflowCheckedBinOp(Ops); 1458 1459 if (Ops.LHS->getType()->isFPOrFPVector()) 1460 return Builder.CreateFSub(Ops.LHS, Ops.RHS, "sub"); 1461 return Builder.CreateSub(Ops.LHS, Ops.RHS, "sub"); 1462 } 1463 1464 if (Ops.E->getLHS()->getType()->isPointerType() && 1465 Ops.E->getLHS()->getType()->getAs<PointerType>()->isVariableArrayType()) { 1466 // The amount of the addition needs to account for the VLA size for 1467 // ptr-int 1468 // The amount of the division needs to account for the VLA size for 1469 // ptr-ptr. 1470 CGF.ErrorUnsupported(Ops.E, "VLA pointer subtraction"); 1471 } 1472 1473 const QualType LHSType = Ops.E->getLHS()->getType(); 1474 const QualType LHSElementType = LHSType->getPointeeType(); 1475 if (!isa<llvm::PointerType>(Ops.RHS->getType())) { 1476 // pointer - int 1477 Value *Idx = Ops.RHS; 1478 unsigned Width = cast<llvm::IntegerType>(Idx->getType())->getBitWidth(); 1479 if (Width < CGF.LLVMPointerWidth) { 1480 // Zero or sign extend the pointer value based on whether the index is 1481 // signed or not. 1482 const llvm::Type *IdxType = 1483 llvm::IntegerType::get(VMContext, CGF.LLVMPointerWidth); 1484 if (Ops.E->getRHS()->getType()->isSignedIntegerType()) 1485 Idx = Builder.CreateSExt(Idx, IdxType, "idx.ext"); 1486 else 1487 Idx = Builder.CreateZExt(Idx, IdxType, "idx.ext"); 1488 } 1489 Idx = Builder.CreateNeg(Idx, "sub.ptr.neg"); 1490 1491 // Handle interface types, which are not represented with a concrete type. 1492 if (const ObjCInterfaceType *OIT = 1493 dyn_cast<ObjCInterfaceType>(LHSElementType)) { 1494 llvm::Value *InterfaceSize = 1495 llvm::ConstantInt::get(Idx->getType(), 1496 CGF.getContext().getTypeSize(OIT) / 8); 1497 Idx = Builder.CreateMul(Idx, InterfaceSize); 1498 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1499 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1500 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "add.ptr"); 1501 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1502 } 1503 1504 // Explicitly handle GNU void* and function pointer arithmetic 1505 // extensions. The GNU void* casts amount to no-ops since our void* type is 1506 // i8*, but this is future proof. 1507 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1508 const llvm::Type *i8Ty = llvm::Type::getInt8PtrTy(VMContext); 1509 Value *LHSCasted = Builder.CreateBitCast(Ops.LHS, i8Ty); 1510 Value *Res = Builder.CreateGEP(LHSCasted, Idx, "sub.ptr"); 1511 return Builder.CreateBitCast(Res, Ops.LHS->getType()); 1512 } 1513 1514 return Builder.CreateInBoundsGEP(Ops.LHS, Idx, "sub.ptr"); 1515 } else { 1516 // pointer - pointer 1517 Value *LHS = Ops.LHS; 1518 Value *RHS = Ops.RHS; 1519 1520 uint64_t ElementSize; 1521 1522 // Handle GCC extension for pointer arithmetic on void* and function pointer 1523 // types. 1524 if (LHSElementType->isVoidType() || LHSElementType->isFunctionType()) { 1525 ElementSize = 1; 1526 } else { 1527 ElementSize = CGF.getContext().getTypeSize(LHSElementType) / 8; 1528 } 1529 1530 const llvm::Type *ResultType = ConvertType(Ops.Ty); 1531 LHS = Builder.CreatePtrToInt(LHS, ResultType, "sub.ptr.lhs.cast"); 1532 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 1533 Value *BytesBetween = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 1534 1535 // Optimize out the shift for element size of 1. 1536 if (ElementSize == 1) 1537 return BytesBetween; 1538 1539 // Otherwise, do a full sdiv. This uses the "exact" form of sdiv, since 1540 // pointer difference in C is only defined in the case where both operands 1541 // are pointing to elements of an array. 1542 Value *BytesPerElt = llvm::ConstantInt::get(ResultType, ElementSize); 1543 return Builder.CreateExactSDiv(BytesBetween, BytesPerElt, "sub.ptr.div"); 1544 } 1545} 1546 1547Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 1548 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1549 // RHS to the same size as the LHS. 1550 Value *RHS = Ops.RHS; 1551 if (Ops.LHS->getType() != RHS->getType()) 1552 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1553 1554 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 1555} 1556 1557Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 1558 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 1559 // RHS to the same size as the LHS. 1560 Value *RHS = Ops.RHS; 1561 if (Ops.LHS->getType() != RHS->getType()) 1562 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 1563 1564 if (Ops.Ty->isUnsignedIntegerType()) 1565 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 1566 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 1567} 1568 1569Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 1570 unsigned SICmpOpc, unsigned FCmpOpc) { 1571 TestAndClearIgnoreResultAssign(); 1572 Value *Result; 1573 QualType LHSTy = E->getLHS()->getType(); 1574 if (LHSTy->isMemberFunctionPointerType()) { 1575 Value *LHSPtr = CGF.EmitAnyExprToTemp(E->getLHS()).getAggregateAddr(); 1576 Value *RHSPtr = CGF.EmitAnyExprToTemp(E->getRHS()).getAggregateAddr(); 1577 llvm::Value *LHSFunc = Builder.CreateStructGEP(LHSPtr, 0); 1578 LHSFunc = Builder.CreateLoad(LHSFunc); 1579 llvm::Value *RHSFunc = Builder.CreateStructGEP(RHSPtr, 0); 1580 RHSFunc = Builder.CreateLoad(RHSFunc); 1581 Value *ResultF = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1582 LHSFunc, RHSFunc, "cmp.func"); 1583 Value *NullPtr = llvm::Constant::getNullValue(LHSFunc->getType()); 1584 Value *ResultNull = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1585 LHSFunc, NullPtr, "cmp.null"); 1586 llvm::Value *LHSAdj = Builder.CreateStructGEP(LHSPtr, 1); 1587 LHSAdj = Builder.CreateLoad(LHSAdj); 1588 llvm::Value *RHSAdj = Builder.CreateStructGEP(RHSPtr, 1); 1589 RHSAdj = Builder.CreateLoad(RHSAdj); 1590 Value *ResultA = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1591 LHSAdj, RHSAdj, "cmp.adj"); 1592 if (E->getOpcode() == BinaryOperator::EQ) { 1593 Result = Builder.CreateOr(ResultNull, ResultA, "or.na"); 1594 Result = Builder.CreateAnd(Result, ResultF, "and.f"); 1595 } else { 1596 assert(E->getOpcode() == BinaryOperator::NE && 1597 "Member pointer comparison other than == or != ?"); 1598 Result = Builder.CreateAnd(ResultNull, ResultA, "and.na"); 1599 Result = Builder.CreateOr(Result, ResultF, "or.f"); 1600 } 1601 } else if (!LHSTy->isAnyComplexType()) { 1602 Value *LHS = Visit(E->getLHS()); 1603 Value *RHS = Visit(E->getRHS()); 1604 1605 if (LHS->getType()->isFPOrFPVector()) { 1606 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 1607 LHS, RHS, "cmp"); 1608 } else if (LHSTy->isSignedIntegerType()) { 1609 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 1610 LHS, RHS, "cmp"); 1611 } else { 1612 // Unsigned integers and pointers. 1613 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1614 LHS, RHS, "cmp"); 1615 } 1616 1617 // If this is a vector comparison, sign extend the result to the appropriate 1618 // vector integer type and return it (don't convert to bool). 1619 if (LHSTy->isVectorType()) 1620 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext"); 1621 1622 } else { 1623 // Complex Comparison: can only be an equality comparison. 1624 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 1625 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 1626 1627 QualType CETy = LHSTy->getAs<ComplexType>()->getElementType(); 1628 1629 Value *ResultR, *ResultI; 1630 if (CETy->isRealFloatingType()) { 1631 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1632 LHS.first, RHS.first, "cmp.r"); 1633 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 1634 LHS.second, RHS.second, "cmp.i"); 1635 } else { 1636 // Complex comparisons can only be equality comparisons. As such, signed 1637 // and unsigned opcodes are the same. 1638 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1639 LHS.first, RHS.first, "cmp.r"); 1640 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 1641 LHS.second, RHS.second, "cmp.i"); 1642 } 1643 1644 if (E->getOpcode() == BinaryOperator::EQ) { 1645 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 1646 } else { 1647 assert(E->getOpcode() == BinaryOperator::NE && 1648 "Complex comparison other than == or != ?"); 1649 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 1650 } 1651 } 1652 1653 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 1654} 1655 1656Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 1657 bool Ignore = TestAndClearIgnoreResultAssign(); 1658 1659 // __block variables need to have the rhs evaluated first, plus this should 1660 // improve codegen just a little. 1661 Value *RHS = Visit(E->getRHS()); 1662 LValue LHS = EmitLValue(E->getLHS()); 1663 1664 // Store the value into the LHS. Bit-fields are handled specially 1665 // because the result is altered by the store, i.e., [C99 6.5.16p1] 1666 // 'An assignment expression has the value of the left operand after 1667 // the assignment...'. 1668 if (LHS.isBitfield()) { 1669 if (!LHS.isVolatileQualified()) { 1670 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType(), 1671 &RHS); 1672 return RHS; 1673 } else 1674 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, E->getType()); 1675 } else 1676 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS, E->getType()); 1677 if (Ignore) 1678 return 0; 1679 return EmitLoadOfLValue(LHS, E->getType()); 1680} 1681 1682Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 1683 const llvm::Type *ResTy = ConvertType(E->getType()); 1684 1685 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. 1686 // If we have 1 && X, just emit X without inserting the control flow. 1687 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1688 if (Cond == 1) { // If we have 1 && X, just emit X. 1689 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1690 // ZExt result to int or bool. 1691 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "land.ext"); 1692 } 1693 1694 // 0 && RHS: If it is safe, just elide the RHS, and return 0/false. 1695 if (!CGF.ContainsLabel(E->getRHS())) 1696 return llvm::Constant::getNullValue(ResTy); 1697 } 1698 1699 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); 1700 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); 1701 1702 // Branch on the LHS first. If it is false, go to the failure (cont) block. 1703 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); 1704 1705 // Any edges into the ContBlock are now from an (indeterminate number of) 1706 // edges from this first condition. All of these values will be false. Start 1707 // setting up the PHI node in the Cont Block for this. 1708 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 1709 "", ContBlock); 1710 PN->reserveOperandSpace(2); // Normal case, two inputs. 1711 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1712 PI != PE; ++PI) 1713 PN->addIncoming(llvm::ConstantInt::getFalse(VMContext), *PI); 1714 1715 CGF.StartConditionalBranch(); 1716 CGF.EmitBlock(RHSBlock); 1717 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1718 CGF.FinishConditionalBranch(); 1719 1720 // Reaquire the RHS block, as there may be subblocks inserted. 1721 RHSBlock = Builder.GetInsertBlock(); 1722 1723 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1724 // into the phi node for the edge with the value of RHSCond. 1725 CGF.EmitBlock(ContBlock); 1726 PN->addIncoming(RHSCond, RHSBlock); 1727 1728 // ZExt result to int. 1729 return Builder.CreateZExtOrBitCast(PN, ResTy, "land.ext"); 1730} 1731 1732Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 1733 const llvm::Type *ResTy = ConvertType(E->getType()); 1734 1735 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. 1736 // If we have 0 || X, just emit X without inserting the control flow. 1737 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getLHS())) { 1738 if (Cond == -1) { // If we have 0 || X, just emit X. 1739 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1740 // ZExt result to int or bool. 1741 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "lor.ext"); 1742 } 1743 1744 // 1 || RHS: If it is safe, just elide the RHS, and return 1/true. 1745 if (!CGF.ContainsLabel(E->getRHS())) 1746 return llvm::ConstantInt::get(ResTy, 1); 1747 } 1748 1749 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); 1750 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); 1751 1752 // Branch on the LHS first. If it is true, go to the success (cont) block. 1753 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); 1754 1755 // Any edges into the ContBlock are now from an (indeterminate number of) 1756 // edges from this first condition. All of these values will be true. Start 1757 // setting up the PHI node in the Cont Block for this. 1758 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 1759 "", ContBlock); 1760 PN->reserveOperandSpace(2); // Normal case, two inputs. 1761 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 1762 PI != PE; ++PI) 1763 PN->addIncoming(llvm::ConstantInt::getTrue(VMContext), *PI); 1764 1765 CGF.StartConditionalBranch(); 1766 1767 // Emit the RHS condition as a bool value. 1768 CGF.EmitBlock(RHSBlock); 1769 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 1770 1771 CGF.FinishConditionalBranch(); 1772 1773 // Reaquire the RHS block, as there may be subblocks inserted. 1774 RHSBlock = Builder.GetInsertBlock(); 1775 1776 // Emit an unconditional branch from this block to ContBlock. Insert an entry 1777 // into the phi node for the edge with the value of RHSCond. 1778 CGF.EmitBlock(ContBlock); 1779 PN->addIncoming(RHSCond, RHSBlock); 1780 1781 // ZExt result to int. 1782 return Builder.CreateZExtOrBitCast(PN, ResTy, "lor.ext"); 1783} 1784 1785Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 1786 CGF.EmitStmt(E->getLHS()); 1787 CGF.EnsureInsertPoint(); 1788 return Visit(E->getRHS()); 1789} 1790 1791//===----------------------------------------------------------------------===// 1792// Other Operators 1793//===----------------------------------------------------------------------===// 1794 1795/// isCheapEnoughToEvaluateUnconditionally - Return true if the specified 1796/// expression is cheap enough and side-effect-free enough to evaluate 1797/// unconditionally instead of conditionally. This is used to convert control 1798/// flow into selects in some cases. 1799static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E, 1800 CodeGenFunction &CGF) { 1801 if (const ParenExpr *PE = dyn_cast<ParenExpr>(E)) 1802 return isCheapEnoughToEvaluateUnconditionally(PE->getSubExpr(), CGF); 1803 1804 // TODO: Allow anything we can constant fold to an integer or fp constant. 1805 if (isa<IntegerLiteral>(E) || isa<CharacterLiteral>(E) || 1806 isa<FloatingLiteral>(E)) 1807 return true; 1808 1809 // Non-volatile automatic variables too, to get "cond ? X : Y" where 1810 // X and Y are local variables. 1811 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) 1812 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) 1813 if (VD->hasLocalStorage() && !(CGF.getContext() 1814 .getCanonicalType(VD->getType()) 1815 .isVolatileQualified())) 1816 return true; 1817 1818 return false; 1819} 1820 1821 1822Value *ScalarExprEmitter:: 1823VisitConditionalOperator(const ConditionalOperator *E) { 1824 TestAndClearIgnoreResultAssign(); 1825 // If the condition constant folds and can be elided, try to avoid emitting 1826 // the condition and the dead arm. 1827 if (int Cond = CGF.ConstantFoldsToSimpleInteger(E->getCond())){ 1828 Expr *Live = E->getLHS(), *Dead = E->getRHS(); 1829 if (Cond == -1) 1830 std::swap(Live, Dead); 1831 1832 // If the dead side doesn't have labels we need, and if the Live side isn't 1833 // the gnu missing ?: extension (which we could handle, but don't bother 1834 // to), just emit the Live part. 1835 if ((!Dead || !CGF.ContainsLabel(Dead)) && // No labels in dead part 1836 Live) // Live part isn't missing. 1837 return Visit(Live); 1838 } 1839 1840 1841 // If this is a really simple expression (like x ? 4 : 5), emit this as a 1842 // select instead of as control flow. We can only do this if it is cheap and 1843 // safe to evaluate the LHS and RHS unconditionally. 1844 if (E->getLHS() && isCheapEnoughToEvaluateUnconditionally(E->getLHS(), 1845 CGF) && 1846 isCheapEnoughToEvaluateUnconditionally(E->getRHS(), CGF)) { 1847 llvm::Value *CondV = CGF.EvaluateExprAsBool(E->getCond()); 1848 llvm::Value *LHS = Visit(E->getLHS()); 1849 llvm::Value *RHS = Visit(E->getRHS()); 1850 return Builder.CreateSelect(CondV, LHS, RHS, "cond"); 1851 } 1852 1853 1854 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 1855 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 1856 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 1857 Value *CondVal = 0; 1858 1859 // If we don't have the GNU missing condition extension, emit a branch on bool 1860 // the normal way. 1861 if (E->getLHS()) { 1862 // Otherwise, just use EmitBranchOnBoolExpr to get small and simple code for 1863 // the branch on bool. 1864 CGF.EmitBranchOnBoolExpr(E->getCond(), LHSBlock, RHSBlock); 1865 } else { 1866 // Otherwise, for the ?: extension, evaluate the conditional and then 1867 // convert it to bool the hard way. We do this explicitly because we need 1868 // the unconverted value for the missing middle value of the ?:. 1869 CondVal = CGF.EmitScalarExpr(E->getCond()); 1870 1871 // In some cases, EmitScalarConversion will delete the "CondVal" expression 1872 // if there are no extra uses (an optimization). Inhibit this by making an 1873 // extra dead use, because we're going to add a use of CondVal later. We 1874 // don't use the builder for this, because we don't want it to get optimized 1875 // away. This leaves dead code, but the ?: extension isn't common. 1876 new llvm::BitCastInst(CondVal, CondVal->getType(), "dummy?:holder", 1877 Builder.GetInsertBlock()); 1878 1879 Value *CondBoolVal = 1880 CGF.EmitScalarConversion(CondVal, E->getCond()->getType(), 1881 CGF.getContext().BoolTy); 1882 Builder.CreateCondBr(CondBoolVal, LHSBlock, RHSBlock); 1883 } 1884 1885 CGF.StartConditionalBranch(); 1886 CGF.EmitBlock(LHSBlock); 1887 1888 // Handle the GNU extension for missing LHS. 1889 Value *LHS; 1890 if (E->getLHS()) 1891 LHS = Visit(E->getLHS()); 1892 else // Perform promotions, to handle cases like "short ?: int" 1893 LHS = EmitScalarConversion(CondVal, E->getCond()->getType(), E->getType()); 1894 1895 CGF.FinishConditionalBranch(); 1896 LHSBlock = Builder.GetInsertBlock(); 1897 CGF.EmitBranch(ContBlock); 1898 1899 CGF.StartConditionalBranch(); 1900 CGF.EmitBlock(RHSBlock); 1901 1902 Value *RHS = Visit(E->getRHS()); 1903 CGF.FinishConditionalBranch(); 1904 RHSBlock = Builder.GetInsertBlock(); 1905 CGF.EmitBranch(ContBlock); 1906 1907 CGF.EmitBlock(ContBlock); 1908 1909 // If the LHS or RHS is a throw expression, it will be legitimately null. 1910 if (!LHS) 1911 return RHS; 1912 if (!RHS) 1913 return LHS; 1914 1915 // Create a PHI node for the real part. 1916 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), "cond"); 1917 PN->reserveOperandSpace(2); 1918 PN->addIncoming(LHS, LHSBlock); 1919 PN->addIncoming(RHS, RHSBlock); 1920 return PN; 1921} 1922 1923Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 1924 return Visit(E->getChosenSubExpr(CGF.getContext())); 1925} 1926 1927Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 1928 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 1929 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 1930 1931 // If EmitVAArg fails, we fall back to the LLVM instruction. 1932 if (!ArgPtr) 1933 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 1934 1935 // FIXME Volatility. 1936 return Builder.CreateLoad(ArgPtr); 1937} 1938 1939Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *BE) { 1940 return CGF.BuildBlockLiteralTmp(BE); 1941} 1942 1943//===----------------------------------------------------------------------===// 1944// Entry Point into this File 1945//===----------------------------------------------------------------------===// 1946 1947/// EmitScalarExpr - Emit the computation of the specified expression of scalar 1948/// type, ignoring the result. 1949Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) { 1950 assert(E && !hasAggregateLLVMType(E->getType()) && 1951 "Invalid scalar expression to emit"); 1952 1953 return ScalarExprEmitter(*this, IgnoreResultAssign) 1954 .Visit(const_cast<Expr*>(E)); 1955} 1956 1957/// EmitScalarConversion - Emit a conversion from the specified type to the 1958/// specified destination type, both of which are LLVM scalar types. 1959Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 1960 QualType DstTy) { 1961 assert(!hasAggregateLLVMType(SrcTy) && !hasAggregateLLVMType(DstTy) && 1962 "Invalid scalar expression to emit"); 1963 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 1964} 1965 1966/// EmitComplexToScalarConversion - Emit a conversion from the specified complex 1967/// type to the specified destination type, where the destination type is an 1968/// LLVM scalar type. 1969Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 1970 QualType SrcTy, 1971 QualType DstTy) { 1972 assert(SrcTy->isAnyComplexType() && !hasAggregateLLVMType(DstTy) && 1973 "Invalid complex -> scalar conversion"); 1974 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 1975 DstTy); 1976} 1977 1978Value *CodeGenFunction::EmitShuffleVector(Value* V1, Value *V2, ...) { 1979 assert(V1->getType() == V2->getType() && 1980 "Vector operands must be of the same type"); 1981 unsigned NumElements = 1982 cast<llvm::VectorType>(V1->getType())->getNumElements(); 1983 1984 va_list va; 1985 va_start(va, V2); 1986 1987 llvm::SmallVector<llvm::Constant*, 16> Args; 1988 for (unsigned i = 0; i < NumElements; i++) { 1989 int n = va_arg(va, int); 1990 assert(n >= 0 && n < (int)NumElements * 2 && 1991 "Vector shuffle index out of bounds!"); 1992 Args.push_back(llvm::ConstantInt::get( 1993 llvm::Type::getInt32Ty(VMContext), n)); 1994 } 1995 1996 const char *Name = va_arg(va, const char *); 1997 va_end(va); 1998 1999 llvm::Constant *Mask = llvm::ConstantVector::get(&Args[0], NumElements); 2000 2001 return Builder.CreateShuffleVector(V1, V2, Mask, Name); 2002} 2003 2004llvm::Value *CodeGenFunction::EmitVector(llvm::Value * const *Vals, 2005 unsigned NumVals, bool isSplat) { 2006 llvm::Value *Vec 2007 = llvm::UndefValue::get(llvm::VectorType::get(Vals[0]->getType(), NumVals)); 2008 2009 for (unsigned i = 0, e = NumVals; i != e; ++i) { 2010 llvm::Value *Val = isSplat ? Vals[0] : Vals[i]; 2011 llvm::Value *Idx = llvm::ConstantInt::get( 2012 llvm::Type::getInt32Ty(VMContext), i); 2013 Vec = Builder.CreateInsertElement(Vec, Val, Idx, "tmp"); 2014 } 2015 2016 return Vec; 2017} 2018 2019LValue CodeGenFunction::EmitObjCIsaExpr(const ObjCIsaExpr *E) { 2020 llvm::Value *V; 2021 // object->isa or (*object).isa 2022 // Generate code as for: *(Class*)object 2023 Expr *BaseExpr = E->getBase(); 2024 if (E->isArrow()) 2025 V = ScalarExprEmitter(*this).EmitLoadOfLValue(BaseExpr); 2026 else 2027 V = EmitLValue(BaseExpr).getAddress(); 2028 2029 // build Class* type 2030 const llvm::Type *ClassPtrTy = ConvertType(E->getType()); 2031 ClassPtrTy = ClassPtrTy->getPointerTo(); 2032 V = Builder.CreateBitCast(V, ClassPtrTy); 2033 LValue LV = LValue::MakeAddr(V, MakeQualifiers(E->getType())); 2034 return LV; 2035} 2036 2037