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 "CGCXXABI.h" 16 #include "CGDebugInfo.h" 17 #include "CGObjCRuntime.h" 18 #include "CodeGenModule.h" 19 #include "clang/AST/ASTContext.h" 20 #include "clang/AST/DeclObjC.h" 21 #include "clang/AST/RecordLayout.h" 22 #include "clang/AST/StmtVisitor.h" 23 #include "clang/Basic/TargetInfo.h" 24 #include "clang/Frontend/CodeGenOptions.h" 25 #include "llvm/IR/Constants.h" 26 #include "llvm/IR/DataLayout.h" 27 #include "llvm/IR/Function.h" 28 #include "llvm/IR/GlobalVariable.h" 29 #include "llvm/IR/Intrinsics.h" 30 #include "llvm/IR/Module.h" 31 #include "llvm/Support/CFG.h" 32 #include <cstdarg> 33 34 using namespace clang; 35 using namespace CodeGen; 36 using llvm::Value; 37 38 //===----------------------------------------------------------------------===// 39 // Scalar Expression Emitter 40 //===----------------------------------------------------------------------===// 41 42 namespace { 43 struct BinOpInfo { 44 Value *LHS; 45 Value *RHS; 46 QualType Ty; // Computation Type. 47 BinaryOperator::Opcode Opcode; // Opcode of BinOp to perform 48 bool FPContractable; 49 const Expr *E; // Entire expr, for error unsupported. May not be binop. 50 }; 51 52 static bool MustVisitNullValue(const Expr *E) { 53 // If a null pointer expression's type is the C++0x nullptr_t, then 54 // it's not necessarily a simple constant and it must be evaluated 55 // for its potential side effects. 56 return E->getType()->isNullPtrType(); 57 } 58 59 class ScalarExprEmitter 60 : public StmtVisitor<ScalarExprEmitter, Value*> { 61 CodeGenFunction &CGF; 62 CGBuilderTy &Builder; 63 bool IgnoreResultAssign; 64 llvm::LLVMContext &VMContext; 65 public: 66 67 ScalarExprEmitter(CodeGenFunction &cgf, bool ira=false) 68 : CGF(cgf), Builder(CGF.Builder), IgnoreResultAssign(ira), 69 VMContext(cgf.getLLVMContext()) { 70 } 71 72 //===--------------------------------------------------------------------===// 73 // Utilities 74 //===--------------------------------------------------------------------===// 75 76 bool TestAndClearIgnoreResultAssign() { 77 bool I = IgnoreResultAssign; 78 IgnoreResultAssign = false; 79 return I; 80 } 81 82 llvm::Type *ConvertType(QualType T) { return CGF.ConvertType(T); } 83 LValue EmitLValue(const Expr *E) { return CGF.EmitLValue(E); } 84 LValue EmitCheckedLValue(const Expr *E, CodeGenFunction::TypeCheckKind TCK) { 85 return CGF.EmitCheckedLValue(E, TCK); 86 } 87 88 void EmitBinOpCheck(Value *Check, const BinOpInfo &Info); 89 90 Value *EmitLoadOfLValue(LValue LV) { 91 return CGF.EmitLoadOfLValue(LV).getScalarVal(); 92 } 93 94 /// EmitLoadOfLValue - Given an expression with complex type that represents a 95 /// value l-value, this method emits the address of the l-value, then loads 96 /// and returns the result. 97 Value *EmitLoadOfLValue(const Expr *E) { 98 return EmitLoadOfLValue(EmitCheckedLValue(E, CodeGenFunction::TCK_Load)); 99 } 100 101 /// EmitConversionToBool - Convert the specified expression value to a 102 /// boolean (i1) truth value. This is equivalent to "Val != 0". 103 Value *EmitConversionToBool(Value *Src, QualType DstTy); 104 105 /// \brief Emit a check that a conversion to or from a floating-point type 106 /// does not overflow. 107 void EmitFloatConversionCheck(Value *OrigSrc, QualType OrigSrcType, 108 Value *Src, QualType SrcType, 109 QualType DstType, llvm::Type *DstTy); 110 111 /// EmitScalarConversion - Emit a conversion from the specified type to the 112 /// specified destination type, both of which are LLVM scalar types. 113 Value *EmitScalarConversion(Value *Src, QualType SrcTy, QualType DstTy); 114 115 /// EmitComplexToScalarConversion - Emit a conversion from the specified 116 /// complex type to the specified destination type, where the destination type 117 /// is an LLVM scalar type. 118 Value *EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 119 QualType SrcTy, QualType DstTy); 120 121 /// EmitNullValue - Emit a value that corresponds to null for the given type. 122 Value *EmitNullValue(QualType Ty); 123 124 /// EmitFloatToBoolConversion - Perform an FP to boolean conversion. 125 Value *EmitFloatToBoolConversion(Value *V) { 126 // Compare against 0.0 for fp scalars. 127 llvm::Value *Zero = llvm::Constant::getNullValue(V->getType()); 128 return Builder.CreateFCmpUNE(V, Zero, "tobool"); 129 } 130 131 /// EmitPointerToBoolConversion - Perform a pointer to boolean conversion. 132 Value *EmitPointerToBoolConversion(Value *V) { 133 Value *Zero = llvm::ConstantPointerNull::get( 134 cast<llvm::PointerType>(V->getType())); 135 return Builder.CreateICmpNE(V, Zero, "tobool"); 136 } 137 138 Value *EmitIntToBoolConversion(Value *V) { 139 // Because of the type rules of C, we often end up computing a 140 // logical value, then zero extending it to int, then wanting it 141 // as a logical value again. Optimize this common case. 142 if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(V)) { 143 if (ZI->getOperand(0)->getType() == Builder.getInt1Ty()) { 144 Value *Result = ZI->getOperand(0); 145 // If there aren't any more uses, zap the instruction to save space. 146 // Note that there can be more uses, for example if this 147 // is the result of an assignment. 148 if (ZI->use_empty()) 149 ZI->eraseFromParent(); 150 return Result; 151 } 152 } 153 154 return Builder.CreateIsNotNull(V, "tobool"); 155 } 156 157 //===--------------------------------------------------------------------===// 158 // Visitor Methods 159 //===--------------------------------------------------------------------===// 160 161 Value *Visit(Expr *E) { 162 return StmtVisitor<ScalarExprEmitter, Value*>::Visit(E); 163 } 164 165 Value *VisitStmt(Stmt *S) { 166 S->dump(CGF.getContext().getSourceManager()); 167 llvm_unreachable("Stmt can't have complex result type!"); 168 } 169 Value *VisitExpr(Expr *S); 170 171 Value *VisitParenExpr(ParenExpr *PE) { 172 return Visit(PE->getSubExpr()); 173 } 174 Value *VisitSubstNonTypeTemplateParmExpr(SubstNonTypeTemplateParmExpr *E) { 175 return Visit(E->getReplacement()); 176 } 177 Value *VisitGenericSelectionExpr(GenericSelectionExpr *GE) { 178 return Visit(GE->getResultExpr()); 179 } 180 181 // Leaves. 182 Value *VisitIntegerLiteral(const IntegerLiteral *E) { 183 return Builder.getInt(E->getValue()); 184 } 185 Value *VisitFloatingLiteral(const FloatingLiteral *E) { 186 return llvm::ConstantFP::get(VMContext, E->getValue()); 187 } 188 Value *VisitCharacterLiteral(const CharacterLiteral *E) { 189 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 190 } 191 Value *VisitObjCBoolLiteralExpr(const ObjCBoolLiteralExpr *E) { 192 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 193 } 194 Value *VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E) { 195 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 196 } 197 Value *VisitCXXScalarValueInitExpr(const CXXScalarValueInitExpr *E) { 198 return EmitNullValue(E->getType()); 199 } 200 Value *VisitGNUNullExpr(const GNUNullExpr *E) { 201 return EmitNullValue(E->getType()); 202 } 203 Value *VisitOffsetOfExpr(OffsetOfExpr *E); 204 Value *VisitUnaryExprOrTypeTraitExpr(const UnaryExprOrTypeTraitExpr *E); 205 Value *VisitAddrLabelExpr(const AddrLabelExpr *E) { 206 llvm::Value *V = CGF.GetAddrOfLabel(E->getLabel()); 207 return Builder.CreateBitCast(V, ConvertType(E->getType())); 208 } 209 210 Value *VisitSizeOfPackExpr(SizeOfPackExpr *E) { 211 return llvm::ConstantInt::get(ConvertType(E->getType()),E->getPackLength()); 212 } 213 214 Value *VisitPseudoObjectExpr(PseudoObjectExpr *E) { 215 return CGF.EmitPseudoObjectRValue(E).getScalarVal(); 216 } 217 218 Value *VisitOpaqueValueExpr(OpaqueValueExpr *E) { 219 if (E->isGLValue()) 220 return EmitLoadOfLValue(CGF.getOpaqueLValueMapping(E)); 221 222 // Otherwise, assume the mapping is the scalar directly. 223 return CGF.getOpaqueRValueMapping(E).getScalarVal(); 224 } 225 226 // l-values. 227 Value *VisitDeclRefExpr(DeclRefExpr *E) { 228 if (CodeGenFunction::ConstantEmission result = CGF.tryEmitAsConstant(E)) { 229 if (result.isReference()) 230 return EmitLoadOfLValue(result.getReferenceLValue(CGF, E)); 231 return result.getValue(); 232 } 233 return EmitLoadOfLValue(E); 234 } 235 236 Value *VisitObjCSelectorExpr(ObjCSelectorExpr *E) { 237 return CGF.EmitObjCSelectorExpr(E); 238 } 239 Value *VisitObjCProtocolExpr(ObjCProtocolExpr *E) { 240 return CGF.EmitObjCProtocolExpr(E); 241 } 242 Value *VisitObjCIvarRefExpr(ObjCIvarRefExpr *E) { 243 return EmitLoadOfLValue(E); 244 } 245 Value *VisitObjCMessageExpr(ObjCMessageExpr *E) { 246 if (E->getMethodDecl() && 247 E->getMethodDecl()->getResultType()->isReferenceType()) 248 return EmitLoadOfLValue(E); 249 return CGF.EmitObjCMessageExpr(E).getScalarVal(); 250 } 251 252 Value *VisitObjCIsaExpr(ObjCIsaExpr *E) { 253 LValue LV = CGF.EmitObjCIsaExpr(E); 254 Value *V = CGF.EmitLoadOfLValue(LV).getScalarVal(); 255 return V; 256 } 257 258 Value *VisitArraySubscriptExpr(ArraySubscriptExpr *E); 259 Value *VisitShuffleVectorExpr(ShuffleVectorExpr *E); 260 Value *VisitMemberExpr(MemberExpr *E); 261 Value *VisitExtVectorElementExpr(Expr *E) { return EmitLoadOfLValue(E); } 262 Value *VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { 263 return EmitLoadOfLValue(E); 264 } 265 266 Value *VisitInitListExpr(InitListExpr *E); 267 268 Value *VisitImplicitValueInitExpr(const ImplicitValueInitExpr *E) { 269 return EmitNullValue(E->getType()); 270 } 271 Value *VisitExplicitCastExpr(ExplicitCastExpr *E) { 272 if (E->getType()->isVariablyModifiedType()) 273 CGF.EmitVariablyModifiedType(E->getType()); 274 return VisitCastExpr(E); 275 } 276 Value *VisitCastExpr(CastExpr *E); 277 278 Value *VisitCallExpr(const CallExpr *E) { 279 if (E->getCallReturnType()->isReferenceType()) 280 return EmitLoadOfLValue(E); 281 282 return CGF.EmitCallExpr(E).getScalarVal(); 283 } 284 285 Value *VisitStmtExpr(const StmtExpr *E); 286 287 // Unary Operators. 288 Value *VisitUnaryPostDec(const UnaryOperator *E) { 289 LValue LV = EmitLValue(E->getSubExpr()); 290 return EmitScalarPrePostIncDec(E, LV, false, false); 291 } 292 Value *VisitUnaryPostInc(const UnaryOperator *E) { 293 LValue LV = EmitLValue(E->getSubExpr()); 294 return EmitScalarPrePostIncDec(E, LV, true, false); 295 } 296 Value *VisitUnaryPreDec(const UnaryOperator *E) { 297 LValue LV = EmitLValue(E->getSubExpr()); 298 return EmitScalarPrePostIncDec(E, LV, false, true); 299 } 300 Value *VisitUnaryPreInc(const UnaryOperator *E) { 301 LValue LV = EmitLValue(E->getSubExpr()); 302 return EmitScalarPrePostIncDec(E, LV, true, true); 303 } 304 305 llvm::Value *EmitAddConsiderOverflowBehavior(const UnaryOperator *E, 306 llvm::Value *InVal, 307 llvm::Value *NextVal, 308 bool IsInc); 309 310 llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 311 bool isInc, bool isPre); 312 313 314 Value *VisitUnaryAddrOf(const UnaryOperator *E) { 315 if (isa<MemberPointerType>(E->getType())) // never sugared 316 return CGF.CGM.getMemberPointerConstant(E); 317 318 return EmitLValue(E->getSubExpr()).getAddress(); 319 } 320 Value *VisitUnaryDeref(const UnaryOperator *E) { 321 if (E->getType()->isVoidType()) 322 return Visit(E->getSubExpr()); // the actual value should be unused 323 return EmitLoadOfLValue(E); 324 } 325 Value *VisitUnaryPlus(const UnaryOperator *E) { 326 // This differs from gcc, though, most likely due to a bug in gcc. 327 TestAndClearIgnoreResultAssign(); 328 return Visit(E->getSubExpr()); 329 } 330 Value *VisitUnaryMinus (const UnaryOperator *E); 331 Value *VisitUnaryNot (const UnaryOperator *E); 332 Value *VisitUnaryLNot (const UnaryOperator *E); 333 Value *VisitUnaryReal (const UnaryOperator *E); 334 Value *VisitUnaryImag (const UnaryOperator *E); 335 Value *VisitUnaryExtension(const UnaryOperator *E) { 336 return Visit(E->getSubExpr()); 337 } 338 339 // C++ 340 Value *VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E) { 341 return EmitLoadOfLValue(E); 342 } 343 344 Value *VisitCXXDefaultArgExpr(CXXDefaultArgExpr *DAE) { 345 return Visit(DAE->getExpr()); 346 } 347 Value *VisitCXXThisExpr(CXXThisExpr *TE) { 348 return CGF.LoadCXXThis(); 349 } 350 351 Value *VisitExprWithCleanups(ExprWithCleanups *E) { 352 CGF.enterFullExpression(E); 353 CodeGenFunction::RunCleanupsScope Scope(CGF); 354 return Visit(E->getSubExpr()); 355 } 356 Value *VisitCXXNewExpr(const CXXNewExpr *E) { 357 return CGF.EmitCXXNewExpr(E); 358 } 359 Value *VisitCXXDeleteExpr(const CXXDeleteExpr *E) { 360 CGF.EmitCXXDeleteExpr(E); 361 return 0; 362 } 363 Value *VisitUnaryTypeTraitExpr(const UnaryTypeTraitExpr *E) { 364 return Builder.getInt1(E->getValue()); 365 } 366 367 Value *VisitBinaryTypeTraitExpr(const BinaryTypeTraitExpr *E) { 368 return llvm::ConstantInt::get(ConvertType(E->getType()), E->getValue()); 369 } 370 371 Value *VisitArrayTypeTraitExpr(const ArrayTypeTraitExpr *E) { 372 return llvm::ConstantInt::get(Builder.getInt32Ty(), E->getValue()); 373 } 374 375 Value *VisitExpressionTraitExpr(const ExpressionTraitExpr *E) { 376 return llvm::ConstantInt::get(Builder.getInt1Ty(), E->getValue()); 377 } 378 379 Value *VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E) { 380 // C++ [expr.pseudo]p1: 381 // The result shall only be used as the operand for the function call 382 // operator (), and the result of such a call has type void. The only 383 // effect is the evaluation of the postfix-expression before the dot or 384 // arrow. 385 CGF.EmitScalarExpr(E->getBase()); 386 return 0; 387 } 388 389 Value *VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E) { 390 return EmitNullValue(E->getType()); 391 } 392 393 Value *VisitCXXThrowExpr(const CXXThrowExpr *E) { 394 CGF.EmitCXXThrowExpr(E); 395 return 0; 396 } 397 398 Value *VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) { 399 return Builder.getInt1(E->getValue()); 400 } 401 402 // Binary Operators. 403 Value *EmitMul(const BinOpInfo &Ops) { 404 if (Ops.Ty->isSignedIntegerOrEnumerationType()) { 405 switch (CGF.getLangOpts().getSignedOverflowBehavior()) { 406 case LangOptions::SOB_Defined: 407 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 408 case LangOptions::SOB_Undefined: 409 if (!CGF.SanOpts->SignedIntegerOverflow) 410 return Builder.CreateNSWMul(Ops.LHS, Ops.RHS, "mul"); 411 // Fall through. 412 case LangOptions::SOB_Trapping: 413 return EmitOverflowCheckedBinOp(Ops); 414 } 415 } 416 417 if (Ops.Ty->isUnsignedIntegerType() && CGF.SanOpts->UnsignedIntegerOverflow) 418 return EmitOverflowCheckedBinOp(Ops); 419 420 if (Ops.LHS->getType()->isFPOrFPVectorTy()) 421 return Builder.CreateFMul(Ops.LHS, Ops.RHS, "mul"); 422 return Builder.CreateMul(Ops.LHS, Ops.RHS, "mul"); 423 } 424 /// Create a binary op that checks for overflow. 425 /// Currently only supports +, - and *. 426 Value *EmitOverflowCheckedBinOp(const BinOpInfo &Ops); 427 428 // Check for undefined division and modulus behaviors. 429 void EmitUndefinedBehaviorIntegerDivAndRemCheck(const BinOpInfo &Ops, 430 llvm::Value *Zero,bool isDiv); 431 // Common helper for getting how wide LHS of shift is. 432 static Value *GetWidthMinusOneValue(Value* LHS,Value* RHS); 433 Value *EmitDiv(const BinOpInfo &Ops); 434 Value *EmitRem(const BinOpInfo &Ops); 435 Value *EmitAdd(const BinOpInfo &Ops); 436 Value *EmitSub(const BinOpInfo &Ops); 437 Value *EmitShl(const BinOpInfo &Ops); 438 Value *EmitShr(const BinOpInfo &Ops); 439 Value *EmitAnd(const BinOpInfo &Ops) { 440 return Builder.CreateAnd(Ops.LHS, Ops.RHS, "and"); 441 } 442 Value *EmitXor(const BinOpInfo &Ops) { 443 return Builder.CreateXor(Ops.LHS, Ops.RHS, "xor"); 444 } 445 Value *EmitOr (const BinOpInfo &Ops) { 446 return Builder.CreateOr(Ops.LHS, Ops.RHS, "or"); 447 } 448 449 BinOpInfo EmitBinOps(const BinaryOperator *E); 450 LValue EmitCompoundAssignLValue(const CompoundAssignOperator *E, 451 Value *(ScalarExprEmitter::*F)(const BinOpInfo &), 452 Value *&Result); 453 454 Value *EmitCompoundAssign(const CompoundAssignOperator *E, 455 Value *(ScalarExprEmitter::*F)(const BinOpInfo &)); 456 457 // Binary operators and binary compound assignment operators. 458 #define HANDLEBINOP(OP) \ 459 Value *VisitBin ## OP(const BinaryOperator *E) { \ 460 return Emit ## OP(EmitBinOps(E)); \ 461 } \ 462 Value *VisitBin ## OP ## Assign(const CompoundAssignOperator *E) { \ 463 return EmitCompoundAssign(E, &ScalarExprEmitter::Emit ## OP); \ 464 } 465 HANDLEBINOP(Mul) 466 HANDLEBINOP(Div) 467 HANDLEBINOP(Rem) 468 HANDLEBINOP(Add) 469 HANDLEBINOP(Sub) 470 HANDLEBINOP(Shl) 471 HANDLEBINOP(Shr) 472 HANDLEBINOP(And) 473 HANDLEBINOP(Xor) 474 HANDLEBINOP(Or) 475 #undef HANDLEBINOP 476 477 // Comparisons. 478 Value *EmitCompare(const BinaryOperator *E, unsigned UICmpOpc, 479 unsigned SICmpOpc, unsigned FCmpOpc); 480 #define VISITCOMP(CODE, UI, SI, FP) \ 481 Value *VisitBin##CODE(const BinaryOperator *E) { \ 482 return EmitCompare(E, llvm::ICmpInst::UI, llvm::ICmpInst::SI, \ 483 llvm::FCmpInst::FP); } 484 VISITCOMP(LT, ICMP_ULT, ICMP_SLT, FCMP_OLT) 485 VISITCOMP(GT, ICMP_UGT, ICMP_SGT, FCMP_OGT) 486 VISITCOMP(LE, ICMP_ULE, ICMP_SLE, FCMP_OLE) 487 VISITCOMP(GE, ICMP_UGE, ICMP_SGE, FCMP_OGE) 488 VISITCOMP(EQ, ICMP_EQ , ICMP_EQ , FCMP_OEQ) 489 VISITCOMP(NE, ICMP_NE , ICMP_NE , FCMP_UNE) 490 #undef VISITCOMP 491 492 Value *VisitBinAssign (const BinaryOperator *E); 493 494 Value *VisitBinLAnd (const BinaryOperator *E); 495 Value *VisitBinLOr (const BinaryOperator *E); 496 Value *VisitBinComma (const BinaryOperator *E); 497 498 Value *VisitBinPtrMemD(const Expr *E) { return EmitLoadOfLValue(E); } 499 Value *VisitBinPtrMemI(const Expr *E) { return EmitLoadOfLValue(E); } 500 501 // Other Operators. 502 Value *VisitBlockExpr(const BlockExpr *BE); 503 Value *VisitAbstractConditionalOperator(const AbstractConditionalOperator *); 504 Value *VisitChooseExpr(ChooseExpr *CE); 505 Value *VisitVAArgExpr(VAArgExpr *VE); 506 Value *VisitObjCStringLiteral(const ObjCStringLiteral *E) { 507 return CGF.EmitObjCStringLiteral(E); 508 } 509 Value *VisitObjCBoxedExpr(ObjCBoxedExpr *E) { 510 return CGF.EmitObjCBoxedExpr(E); 511 } 512 Value *VisitObjCArrayLiteral(ObjCArrayLiteral *E) { 513 return CGF.EmitObjCArrayLiteral(E); 514 } 515 Value *VisitObjCDictionaryLiteral(ObjCDictionaryLiteral *E) { 516 return CGF.EmitObjCDictionaryLiteral(E); 517 } 518 Value *VisitAsTypeExpr(AsTypeExpr *CE); 519 Value *VisitAtomicExpr(AtomicExpr *AE); 520 }; 521 } // end anonymous namespace. 522 523 //===----------------------------------------------------------------------===// 524 // Utilities 525 //===----------------------------------------------------------------------===// 526 527 /// EmitConversionToBool - Convert the specified expression value to a 528 /// boolean (i1) truth value. This is equivalent to "Val != 0". 529 Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) { 530 assert(SrcType.isCanonical() && "EmitScalarConversion strips typedefs"); 531 532 if (SrcType->isRealFloatingType()) 533 return EmitFloatToBoolConversion(Src); 534 535 if (const MemberPointerType *MPT = dyn_cast<MemberPointerType>(SrcType)) 536 return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, Src, MPT); 537 538 assert((SrcType->isIntegerType() || isa<llvm::PointerType>(Src->getType())) && 539 "Unknown scalar type to convert"); 540 541 if (isa<llvm::IntegerType>(Src->getType())) 542 return EmitIntToBoolConversion(Src); 543 544 assert(isa<llvm::PointerType>(Src->getType())); 545 return EmitPointerToBoolConversion(Src); 546 } 547 548 void ScalarExprEmitter::EmitFloatConversionCheck(Value *OrigSrc, 549 QualType OrigSrcType, 550 Value *Src, QualType SrcType, 551 QualType DstType, 552 llvm::Type *DstTy) { 553 using llvm::APFloat; 554 using llvm::APSInt; 555 556 llvm::Type *SrcTy = Src->getType(); 557 558 llvm::Value *Check = 0; 559 if (llvm::IntegerType *IntTy = dyn_cast<llvm::IntegerType>(SrcTy)) { 560 // Integer to floating-point. This can fail for unsigned short -> __half 561 // or unsigned __int128 -> float. 562 assert(DstType->isFloatingType()); 563 bool SrcIsUnsigned = OrigSrcType->isUnsignedIntegerOrEnumerationType(); 564 565 APFloat LargestFloat = 566 APFloat::getLargest(CGF.getContext().getFloatTypeSemantics(DstType)); 567 APSInt LargestInt(IntTy->getBitWidth(), SrcIsUnsigned); 568 569 bool IsExact; 570 if (LargestFloat.convertToInteger(LargestInt, APFloat::rmTowardZero, 571 &IsExact) != APFloat::opOK) 572 // The range of representable values of this floating point type includes 573 // all values of this integer type. Don't need an overflow check. 574 return; 575 576 llvm::Value *Max = llvm::ConstantInt::get(VMContext, LargestInt); 577 if (SrcIsUnsigned) 578 Check = Builder.CreateICmpULE(Src, Max); 579 else { 580 llvm::Value *Min = llvm::ConstantInt::get(VMContext, -LargestInt); 581 llvm::Value *GE = Builder.CreateICmpSGE(Src, Min); 582 llvm::Value *LE = Builder.CreateICmpSLE(Src, Max); 583 Check = Builder.CreateAnd(GE, LE); 584 } 585 } else { 586 // Floating-point to integer or floating-point to floating-point. This has 587 // undefined behavior if the source is +-Inf, NaN, or doesn't fit into the 588 // destination type. 589 const llvm::fltSemantics &SrcSema = 590 CGF.getContext().getFloatTypeSemantics(OrigSrcType); 591 APFloat MaxSrc(SrcSema, APFloat::uninitialized); 592 APFloat MinSrc(SrcSema, APFloat::uninitialized); 593 594 if (isa<llvm::IntegerType>(DstTy)) { 595 unsigned Width = CGF.getContext().getIntWidth(DstType); 596 bool Unsigned = DstType->isUnsignedIntegerOrEnumerationType(); 597 598 APSInt Min = APSInt::getMinValue(Width, Unsigned); 599 if (MinSrc.convertFromAPInt(Min, !Unsigned, APFloat::rmTowardZero) & 600 APFloat::opOverflow) 601 // Don't need an overflow check for lower bound. Just check for 602 // -Inf/NaN. 603 MinSrc = APFloat::getLargest(SrcSema, true); 604 605 APSInt Max = APSInt::getMaxValue(Width, Unsigned); 606 if (MaxSrc.convertFromAPInt(Max, !Unsigned, APFloat::rmTowardZero) & 607 APFloat::opOverflow) 608 // Don't need an overflow check for upper bound. Just check for 609 // +Inf/NaN. 610 MaxSrc = APFloat::getLargest(SrcSema, false); 611 } else { 612 const llvm::fltSemantics &DstSema = 613 CGF.getContext().getFloatTypeSemantics(DstType); 614 bool IsInexact; 615 616 MinSrc = APFloat::getLargest(DstSema, true); 617 if (MinSrc.convert(SrcSema, APFloat::rmTowardZero, &IsInexact) & 618 APFloat::opOverflow) 619 MinSrc = APFloat::getLargest(SrcSema, true); 620 621 MaxSrc = APFloat::getLargest(DstSema, false); 622 if (MaxSrc.convert(SrcSema, APFloat::rmTowardZero, &IsInexact) & 623 APFloat::opOverflow) 624 MaxSrc = APFloat::getLargest(SrcSema, false); 625 } 626 627 // If we're converting from __half, convert the range to float to match 628 // the type of src. 629 if (OrigSrcType->isHalfType()) { 630 const llvm::fltSemantics &Sema = 631 CGF.getContext().getFloatTypeSemantics(SrcType); 632 bool IsInexact; 633 MinSrc.convert(Sema, APFloat::rmTowardZero, &IsInexact); 634 MaxSrc.convert(Sema, APFloat::rmTowardZero, &IsInexact); 635 } 636 637 llvm::Value *GE = 638 Builder.CreateFCmpOGE(Src, llvm::ConstantFP::get(VMContext, MinSrc)); 639 llvm::Value *LE = 640 Builder.CreateFCmpOLE(Src, llvm::ConstantFP::get(VMContext, MaxSrc)); 641 Check = Builder.CreateAnd(GE, LE); 642 } 643 644 // FIXME: Provide a SourceLocation. 645 llvm::Constant *StaticArgs[] = { 646 CGF.EmitCheckTypeDescriptor(OrigSrcType), 647 CGF.EmitCheckTypeDescriptor(DstType) 648 }; 649 CGF.EmitCheck(Check, "float_cast_overflow", StaticArgs, OrigSrc, 650 CodeGenFunction::CRK_Recoverable); 651 } 652 653 /// EmitScalarConversion - Emit a conversion from the specified type to the 654 /// specified destination type, both of which are LLVM scalar types. 655 Value *ScalarExprEmitter::EmitScalarConversion(Value *Src, QualType SrcType, 656 QualType DstType) { 657 SrcType = CGF.getContext().getCanonicalType(SrcType); 658 DstType = CGF.getContext().getCanonicalType(DstType); 659 if (SrcType == DstType) return Src; 660 661 if (DstType->isVoidType()) return 0; 662 663 llvm::Value *OrigSrc = Src; 664 QualType OrigSrcType = SrcType; 665 llvm::Type *SrcTy = Src->getType(); 666 667 // If casting to/from storage-only half FP, use special intrinsics. 668 if (SrcType->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) { 669 Src = Builder.CreateCall(CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16), Src); 670 SrcType = CGF.getContext().FloatTy; 671 SrcTy = CGF.FloatTy; 672 } 673 674 // Handle conversions to bool first, they are special: comparisons against 0. 675 if (DstType->isBooleanType()) 676 return EmitConversionToBool(Src, SrcType); 677 678 llvm::Type *DstTy = ConvertType(DstType); 679 680 // Ignore conversions like int -> uint. 681 if (SrcTy == DstTy) 682 return Src; 683 684 // Handle pointer conversions next: pointers can only be converted to/from 685 // other pointers and integers. Check for pointer types in terms of LLVM, as 686 // some native types (like Obj-C id) may map to a pointer type. 687 if (isa<llvm::PointerType>(DstTy)) { 688 // The source value may be an integer, or a pointer. 689 if (isa<llvm::PointerType>(SrcTy)) 690 return Builder.CreateBitCast(Src, DstTy, "conv"); 691 692 assert(SrcType->isIntegerType() && "Not ptr->ptr or int->ptr conversion?"); 693 // First, convert to the correct width so that we control the kind of 694 // extension. 695 llvm::Type *MiddleTy = CGF.IntPtrTy; 696 bool InputSigned = SrcType->isSignedIntegerOrEnumerationType(); 697 llvm::Value* IntResult = 698 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 699 // Then, cast to pointer. 700 return Builder.CreateIntToPtr(IntResult, DstTy, "conv"); 701 } 702 703 if (isa<llvm::PointerType>(SrcTy)) { 704 // Must be an ptr to int cast. 705 assert(isa<llvm::IntegerType>(DstTy) && "not ptr->int?"); 706 return Builder.CreatePtrToInt(Src, DstTy, "conv"); 707 } 708 709 // A scalar can be splatted to an extended vector of the same element type 710 if (DstType->isExtVectorType() && !SrcType->isVectorType()) { 711 // Cast the scalar to element type 712 QualType EltTy = DstType->getAs<ExtVectorType>()->getElementType(); 713 llvm::Value *Elt = EmitScalarConversion(Src, SrcType, EltTy); 714 715 // Splat the element across to all elements 716 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 717 return Builder.CreateVectorSplat(NumElements, Elt, "splat"); 718 } 719 720 // Allow bitcast from vector to integer/fp of the same size. 721 if (isa<llvm::VectorType>(SrcTy) || 722 isa<llvm::VectorType>(DstTy)) 723 return Builder.CreateBitCast(Src, DstTy, "conv"); 724 725 // Finally, we have the arithmetic types: real int/float. 726 Value *Res = NULL; 727 llvm::Type *ResTy = DstTy; 728 729 // An overflowing conversion has undefined behavior if either the source type 730 // or the destination type is a floating-point type. 731 if (CGF.SanOpts->FloatCastOverflow && 732 (OrigSrcType->isFloatingType() || DstType->isFloatingType())) 733 EmitFloatConversionCheck(OrigSrc, OrigSrcType, Src, SrcType, DstType, 734 DstTy); 735 736 // Cast to half via float 737 if (DstType->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) 738 DstTy = CGF.FloatTy; 739 740 if (isa<llvm::IntegerType>(SrcTy)) { 741 bool InputSigned = SrcType->isSignedIntegerOrEnumerationType(); 742 if (isa<llvm::IntegerType>(DstTy)) 743 Res = Builder.CreateIntCast(Src, DstTy, InputSigned, "conv"); 744 else if (InputSigned) 745 Res = Builder.CreateSIToFP(Src, DstTy, "conv"); 746 else 747 Res = Builder.CreateUIToFP(Src, DstTy, "conv"); 748 } else if (isa<llvm::IntegerType>(DstTy)) { 749 assert(SrcTy->isFloatingPointTy() && "Unknown real conversion"); 750 if (DstType->isSignedIntegerOrEnumerationType()) 751 Res = Builder.CreateFPToSI(Src, DstTy, "conv"); 752 else 753 Res = Builder.CreateFPToUI(Src, DstTy, "conv"); 754 } else { 755 assert(SrcTy->isFloatingPointTy() && DstTy->isFloatingPointTy() && 756 "Unknown real conversion"); 757 if (DstTy->getTypeID() < SrcTy->getTypeID()) 758 Res = Builder.CreateFPTrunc(Src, DstTy, "conv"); 759 else 760 Res = Builder.CreateFPExt(Src, DstTy, "conv"); 761 } 762 763 if (DstTy != ResTy) { 764 assert(ResTy->isIntegerTy(16) && "Only half FP requires extra conversion"); 765 Res = Builder.CreateCall(CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16), Res); 766 } 767 768 return Res; 769 } 770 771 /// EmitComplexToScalarConversion - Emit a conversion from the specified complex 772 /// type to the specified destination type, where the destination type is an 773 /// LLVM scalar type. 774 Value *ScalarExprEmitter:: 775 EmitComplexToScalarConversion(CodeGenFunction::ComplexPairTy Src, 776 QualType SrcTy, QualType DstTy) { 777 // Get the source element type. 778 SrcTy = SrcTy->castAs<ComplexType>()->getElementType(); 779 780 // Handle conversions to bool first, they are special: comparisons against 0. 781 if (DstTy->isBooleanType()) { 782 // Complex != 0 -> (Real != 0) | (Imag != 0) 783 Src.first = EmitScalarConversion(Src.first, SrcTy, DstTy); 784 Src.second = EmitScalarConversion(Src.second, SrcTy, DstTy); 785 return Builder.CreateOr(Src.first, Src.second, "tobool"); 786 } 787 788 // C99 6.3.1.7p2: "When a value of complex type is converted to a real type, 789 // the imaginary part of the complex value is discarded and the value of the 790 // real part is converted according to the conversion rules for the 791 // corresponding real type. 792 return EmitScalarConversion(Src.first, SrcTy, DstTy); 793 } 794 795 Value *ScalarExprEmitter::EmitNullValue(QualType Ty) { 796 return CGF.EmitFromMemory(CGF.CGM.EmitNullConstant(Ty), Ty); 797 } 798 799 /// \brief Emit a sanitization check for the given "binary" operation (which 800 /// might actually be a unary increment which has been lowered to a binary 801 /// operation). The check passes if \p Check, which is an \c i1, is \c true. 802 void ScalarExprEmitter::EmitBinOpCheck(Value *Check, const BinOpInfo &Info) { 803 StringRef CheckName; 804 SmallVector<llvm::Constant *, 4> StaticData; 805 SmallVector<llvm::Value *, 2> DynamicData; 806 807 BinaryOperatorKind Opcode = Info.Opcode; 808 if (BinaryOperator::isCompoundAssignmentOp(Opcode)) 809 Opcode = BinaryOperator::getOpForCompoundAssignment(Opcode); 810 811 StaticData.push_back(CGF.EmitCheckSourceLocation(Info.E->getExprLoc())); 812 const UnaryOperator *UO = dyn_cast<UnaryOperator>(Info.E); 813 if (UO && UO->getOpcode() == UO_Minus) { 814 CheckName = "negate_overflow"; 815 StaticData.push_back(CGF.EmitCheckTypeDescriptor(UO->getType())); 816 DynamicData.push_back(Info.RHS); 817 } else { 818 if (BinaryOperator::isShiftOp(Opcode)) { 819 // Shift LHS negative or too large, or RHS out of bounds. 820 CheckName = "shift_out_of_bounds"; 821 const BinaryOperator *BO = cast<BinaryOperator>(Info.E); 822 StaticData.push_back( 823 CGF.EmitCheckTypeDescriptor(BO->getLHS()->getType())); 824 StaticData.push_back( 825 CGF.EmitCheckTypeDescriptor(BO->getRHS()->getType())); 826 } else if (Opcode == BO_Div || Opcode == BO_Rem) { 827 // Divide or modulo by zero, or signed overflow (eg INT_MAX / -1). 828 CheckName = "divrem_overflow"; 829 StaticData.push_back(CGF.EmitCheckTypeDescriptor(Info.Ty)); 830 } else { 831 // Signed arithmetic overflow (+, -, *). 832 switch (Opcode) { 833 case BO_Add: CheckName = "add_overflow"; break; 834 case BO_Sub: CheckName = "sub_overflow"; break; 835 case BO_Mul: CheckName = "mul_overflow"; break; 836 default: llvm_unreachable("unexpected opcode for bin op check"); 837 } 838 StaticData.push_back(CGF.EmitCheckTypeDescriptor(Info.Ty)); 839 } 840 DynamicData.push_back(Info.LHS); 841 DynamicData.push_back(Info.RHS); 842 } 843 844 CGF.EmitCheck(Check, CheckName, StaticData, DynamicData, 845 CodeGenFunction::CRK_Recoverable); 846 } 847 848 //===----------------------------------------------------------------------===// 849 // Visitor Methods 850 //===----------------------------------------------------------------------===// 851 852 Value *ScalarExprEmitter::VisitExpr(Expr *E) { 853 CGF.ErrorUnsupported(E, "scalar expression"); 854 if (E->getType()->isVoidType()) 855 return 0; 856 return llvm::UndefValue::get(CGF.ConvertType(E->getType())); 857 } 858 859 Value *ScalarExprEmitter::VisitShuffleVectorExpr(ShuffleVectorExpr *E) { 860 // Vector Mask Case 861 if (E->getNumSubExprs() == 2 || 862 (E->getNumSubExprs() == 3 && E->getExpr(2)->getType()->isVectorType())) { 863 Value *LHS = CGF.EmitScalarExpr(E->getExpr(0)); 864 Value *RHS = CGF.EmitScalarExpr(E->getExpr(1)); 865 Value *Mask; 866 867 llvm::VectorType *LTy = cast<llvm::VectorType>(LHS->getType()); 868 unsigned LHSElts = LTy->getNumElements(); 869 870 if (E->getNumSubExprs() == 3) { 871 Mask = CGF.EmitScalarExpr(E->getExpr(2)); 872 873 // Shuffle LHS & RHS into one input vector. 874 SmallVector<llvm::Constant*, 32> concat; 875 for (unsigned i = 0; i != LHSElts; ++i) { 876 concat.push_back(Builder.getInt32(2*i)); 877 concat.push_back(Builder.getInt32(2*i+1)); 878 } 879 880 Value* CV = llvm::ConstantVector::get(concat); 881 LHS = Builder.CreateShuffleVector(LHS, RHS, CV, "concat"); 882 LHSElts *= 2; 883 } else { 884 Mask = RHS; 885 } 886 887 llvm::VectorType *MTy = cast<llvm::VectorType>(Mask->getType()); 888 llvm::Constant* EltMask; 889 890 // Treat vec3 like vec4. 891 if ((LHSElts == 6) && (E->getNumSubExprs() == 3)) 892 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 893 (1 << llvm::Log2_32(LHSElts+2))-1); 894 else if ((LHSElts == 3) && (E->getNumSubExprs() == 2)) 895 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 896 (1 << llvm::Log2_32(LHSElts+1))-1); 897 else 898 EltMask = llvm::ConstantInt::get(MTy->getElementType(), 899 (1 << llvm::Log2_32(LHSElts))-1); 900 901 // Mask off the high bits of each shuffle index. 902 Value *MaskBits = llvm::ConstantVector::getSplat(MTy->getNumElements(), 903 EltMask); 904 Mask = Builder.CreateAnd(Mask, MaskBits, "mask"); 905 906 // newv = undef 907 // mask = mask & maskbits 908 // for each elt 909 // n = extract mask i 910 // x = extract val n 911 // newv = insert newv, x, i 912 llvm::VectorType *RTy = llvm::VectorType::get(LTy->getElementType(), 913 MTy->getNumElements()); 914 Value* NewV = llvm::UndefValue::get(RTy); 915 for (unsigned i = 0, e = MTy->getNumElements(); i != e; ++i) { 916 Value *IIndx = Builder.getInt32(i); 917 Value *Indx = Builder.CreateExtractElement(Mask, IIndx, "shuf_idx"); 918 Indx = Builder.CreateZExt(Indx, CGF.Int32Ty, "idx_zext"); 919 920 // Handle vec3 special since the index will be off by one for the RHS. 921 if ((LHSElts == 6) && (E->getNumSubExprs() == 3)) { 922 Value *cmpIndx, *newIndx; 923 cmpIndx = Builder.CreateICmpUGT(Indx, Builder.getInt32(3), 924 "cmp_shuf_idx"); 925 newIndx = Builder.CreateSub(Indx, Builder.getInt32(1), "shuf_idx_adj"); 926 Indx = Builder.CreateSelect(cmpIndx, newIndx, Indx, "sel_shuf_idx"); 927 } 928 Value *VExt = Builder.CreateExtractElement(LHS, Indx, "shuf_elt"); 929 NewV = Builder.CreateInsertElement(NewV, VExt, IIndx, "shuf_ins"); 930 } 931 return NewV; 932 } 933 934 Value* V1 = CGF.EmitScalarExpr(E->getExpr(0)); 935 Value* V2 = CGF.EmitScalarExpr(E->getExpr(1)); 936 937 // Handle vec3 special since the index will be off by one for the RHS. 938 llvm::VectorType *VTy = cast<llvm::VectorType>(V1->getType()); 939 SmallVector<llvm::Constant*, 32> indices; 940 for (unsigned i = 2; i < E->getNumSubExprs(); i++) { 941 unsigned Idx = E->getShuffleMaskIdx(CGF.getContext(), i-2); 942 if (VTy->getNumElements() == 3 && Idx > 3) 943 Idx -= 1; 944 indices.push_back(Builder.getInt32(Idx)); 945 } 946 947 Value *SV = llvm::ConstantVector::get(indices); 948 return Builder.CreateShuffleVector(V1, V2, SV, "shuffle"); 949 } 950 Value *ScalarExprEmitter::VisitMemberExpr(MemberExpr *E) { 951 llvm::APSInt Value; 952 if (E->EvaluateAsInt(Value, CGF.getContext(), Expr::SE_AllowSideEffects)) { 953 if (E->isArrow()) 954 CGF.EmitScalarExpr(E->getBase()); 955 else 956 EmitLValue(E->getBase()); 957 return Builder.getInt(Value); 958 } 959 960 // Emit debug info for aggregate now, if it was delayed to reduce 961 // debug info size. 962 CGDebugInfo *DI = CGF.getDebugInfo(); 963 if (DI && 964 CGF.CGM.getCodeGenOpts().getDebugInfo() 965 == CodeGenOptions::LimitedDebugInfo) { 966 QualType PQTy = E->getBase()->IgnoreParenImpCasts()->getType(); 967 if (const PointerType * PTy = dyn_cast<PointerType>(PQTy)) 968 if (FieldDecl *M = dyn_cast<FieldDecl>(E->getMemberDecl())) 969 DI->getOrCreateRecordType(PTy->getPointeeType(), 970 M->getParent()->getLocation()); 971 } 972 return EmitLoadOfLValue(E); 973 } 974 975 Value *ScalarExprEmitter::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { 976 TestAndClearIgnoreResultAssign(); 977 978 // Emit subscript expressions in rvalue context's. For most cases, this just 979 // loads the lvalue formed by the subscript expr. However, we have to be 980 // careful, because the base of a vector subscript is occasionally an rvalue, 981 // so we can't get it as an lvalue. 982 if (!E->getBase()->getType()->isVectorType()) 983 return EmitLoadOfLValue(E); 984 985 // Handle the vector case. The base must be a vector, the index must be an 986 // integer value. 987 Value *Base = Visit(E->getBase()); 988 Value *Idx = Visit(E->getIdx()); 989 QualType IdxTy = E->getIdx()->getType(); 990 991 if (CGF.SanOpts->Bounds) 992 CGF.EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, /*Accessed*/true); 993 994 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType(); 995 Idx = Builder.CreateIntCast(Idx, CGF.Int32Ty, IdxSigned, "vecidxcast"); 996 return Builder.CreateExtractElement(Base, Idx, "vecext"); 997 } 998 999 static llvm::Constant *getMaskElt(llvm::ShuffleVectorInst *SVI, unsigned Idx, 1000 unsigned Off, llvm::Type *I32Ty) { 1001 int MV = SVI->getMaskValue(Idx); 1002 if (MV == -1) 1003 return llvm::UndefValue::get(I32Ty); 1004 return llvm::ConstantInt::get(I32Ty, Off+MV); 1005 } 1006 1007 Value *ScalarExprEmitter::VisitInitListExpr(InitListExpr *E) { 1008 bool Ignore = TestAndClearIgnoreResultAssign(); 1009 (void)Ignore; 1010 assert (Ignore == false && "init list ignored"); 1011 unsigned NumInitElements = E->getNumInits(); 1012 1013 if (E->hadArrayRangeDesignator()) 1014 CGF.ErrorUnsupported(E, "GNU array range designator extension"); 1015 1016 llvm::VectorType *VType = 1017 dyn_cast<llvm::VectorType>(ConvertType(E->getType())); 1018 1019 if (!VType) { 1020 if (NumInitElements == 0) { 1021 // C++11 value-initialization for the scalar. 1022 return EmitNullValue(E->getType()); 1023 } 1024 // We have a scalar in braces. Just use the first element. 1025 return Visit(E->getInit(0)); 1026 } 1027 1028 unsigned ResElts = VType->getNumElements(); 1029 1030 // Loop over initializers collecting the Value for each, and remembering 1031 // whether the source was swizzle (ExtVectorElementExpr). This will allow 1032 // us to fold the shuffle for the swizzle into the shuffle for the vector 1033 // initializer, since LLVM optimizers generally do not want to touch 1034 // shuffles. 1035 unsigned CurIdx = 0; 1036 bool VIsUndefShuffle = false; 1037 llvm::Value *V = llvm::UndefValue::get(VType); 1038 for (unsigned i = 0; i != NumInitElements; ++i) { 1039 Expr *IE = E->getInit(i); 1040 Value *Init = Visit(IE); 1041 SmallVector<llvm::Constant*, 16> Args; 1042 1043 llvm::VectorType *VVT = dyn_cast<llvm::VectorType>(Init->getType()); 1044 1045 // Handle scalar elements. If the scalar initializer is actually one 1046 // element of a different vector of the same width, use shuffle instead of 1047 // extract+insert. 1048 if (!VVT) { 1049 if (isa<ExtVectorElementExpr>(IE)) { 1050 llvm::ExtractElementInst *EI = cast<llvm::ExtractElementInst>(Init); 1051 1052 if (EI->getVectorOperandType()->getNumElements() == ResElts) { 1053 llvm::ConstantInt *C = cast<llvm::ConstantInt>(EI->getIndexOperand()); 1054 Value *LHS = 0, *RHS = 0; 1055 if (CurIdx == 0) { 1056 // insert into undef -> shuffle (src, undef) 1057 Args.push_back(C); 1058 Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty)); 1059 1060 LHS = EI->getVectorOperand(); 1061 RHS = V; 1062 VIsUndefShuffle = true; 1063 } else if (VIsUndefShuffle) { 1064 // insert into undefshuffle && size match -> shuffle (v, src) 1065 llvm::ShuffleVectorInst *SVV = cast<llvm::ShuffleVectorInst>(V); 1066 for (unsigned j = 0; j != CurIdx; ++j) 1067 Args.push_back(getMaskElt(SVV, j, 0, CGF.Int32Ty)); 1068 Args.push_back(Builder.getInt32(ResElts + C->getZExtValue())); 1069 Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty)); 1070 1071 LHS = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 1072 RHS = EI->getVectorOperand(); 1073 VIsUndefShuffle = false; 1074 } 1075 if (!Args.empty()) { 1076 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 1077 V = Builder.CreateShuffleVector(LHS, RHS, Mask); 1078 ++CurIdx; 1079 continue; 1080 } 1081 } 1082 } 1083 V = Builder.CreateInsertElement(V, Init, Builder.getInt32(CurIdx), 1084 "vecinit"); 1085 VIsUndefShuffle = false; 1086 ++CurIdx; 1087 continue; 1088 } 1089 1090 unsigned InitElts = VVT->getNumElements(); 1091 1092 // If the initializer is an ExtVecEltExpr (a swizzle), and the swizzle's 1093 // input is the same width as the vector being constructed, generate an 1094 // optimized shuffle of the swizzle input into the result. 1095 unsigned Offset = (CurIdx == 0) ? 0 : ResElts; 1096 if (isa<ExtVectorElementExpr>(IE)) { 1097 llvm::ShuffleVectorInst *SVI = cast<llvm::ShuffleVectorInst>(Init); 1098 Value *SVOp = SVI->getOperand(0); 1099 llvm::VectorType *OpTy = cast<llvm::VectorType>(SVOp->getType()); 1100 1101 if (OpTy->getNumElements() == ResElts) { 1102 for (unsigned j = 0; j != CurIdx; ++j) { 1103 // If the current vector initializer is a shuffle with undef, merge 1104 // this shuffle directly into it. 1105 if (VIsUndefShuffle) { 1106 Args.push_back(getMaskElt(cast<llvm::ShuffleVectorInst>(V), j, 0, 1107 CGF.Int32Ty)); 1108 } else { 1109 Args.push_back(Builder.getInt32(j)); 1110 } 1111 } 1112 for (unsigned j = 0, je = InitElts; j != je; ++j) 1113 Args.push_back(getMaskElt(SVI, j, Offset, CGF.Int32Ty)); 1114 Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty)); 1115 1116 if (VIsUndefShuffle) 1117 V = cast<llvm::ShuffleVectorInst>(V)->getOperand(0); 1118 1119 Init = SVOp; 1120 } 1121 } 1122 1123 // Extend init to result vector length, and then shuffle its contribution 1124 // to the vector initializer into V. 1125 if (Args.empty()) { 1126 for (unsigned j = 0; j != InitElts; ++j) 1127 Args.push_back(Builder.getInt32(j)); 1128 Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty)); 1129 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 1130 Init = Builder.CreateShuffleVector(Init, llvm::UndefValue::get(VVT), 1131 Mask, "vext"); 1132 1133 Args.clear(); 1134 for (unsigned j = 0; j != CurIdx; ++j) 1135 Args.push_back(Builder.getInt32(j)); 1136 for (unsigned j = 0; j != InitElts; ++j) 1137 Args.push_back(Builder.getInt32(j+Offset)); 1138 Args.resize(ResElts, llvm::UndefValue::get(CGF.Int32Ty)); 1139 } 1140 1141 // If V is undef, make sure it ends up on the RHS of the shuffle to aid 1142 // merging subsequent shuffles into this one. 1143 if (CurIdx == 0) 1144 std::swap(V, Init); 1145 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 1146 V = Builder.CreateShuffleVector(V, Init, Mask, "vecinit"); 1147 VIsUndefShuffle = isa<llvm::UndefValue>(Init); 1148 CurIdx += InitElts; 1149 } 1150 1151 // FIXME: evaluate codegen vs. shuffling against constant null vector. 1152 // Emit remaining default initializers. 1153 llvm::Type *EltTy = VType->getElementType(); 1154 1155 // Emit remaining default initializers 1156 for (/* Do not initialize i*/; CurIdx < ResElts; ++CurIdx) { 1157 Value *Idx = Builder.getInt32(CurIdx); 1158 llvm::Value *Init = llvm::Constant::getNullValue(EltTy); 1159 V = Builder.CreateInsertElement(V, Init, Idx, "vecinit"); 1160 } 1161 return V; 1162 } 1163 1164 static bool ShouldNullCheckClassCastValue(const CastExpr *CE) { 1165 const Expr *E = CE->getSubExpr(); 1166 1167 if (CE->getCastKind() == CK_UncheckedDerivedToBase) 1168 return false; 1169 1170 if (isa<CXXThisExpr>(E)) { 1171 // We always assume that 'this' is never null. 1172 return false; 1173 } 1174 1175 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(CE)) { 1176 // And that glvalue casts are never null. 1177 if (ICE->getValueKind() != VK_RValue) 1178 return false; 1179 } 1180 1181 return true; 1182 } 1183 1184 // VisitCastExpr - Emit code for an explicit or implicit cast. Implicit casts 1185 // have to handle a more broad range of conversions than explicit casts, as they 1186 // handle things like function to ptr-to-function decay etc. 1187 Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) { 1188 Expr *E = CE->getSubExpr(); 1189 QualType DestTy = CE->getType(); 1190 CastKind Kind = CE->getCastKind(); 1191 1192 if (!DestTy->isVoidType()) 1193 TestAndClearIgnoreResultAssign(); 1194 1195 // Since almost all cast kinds apply to scalars, this switch doesn't have 1196 // a default case, so the compiler will warn on a missing case. The cases 1197 // are in the same order as in the CastKind enum. 1198 switch (Kind) { 1199 case CK_Dependent: llvm_unreachable("dependent cast kind in IR gen!"); 1200 case CK_BuiltinFnToFnPtr: 1201 llvm_unreachable("builtin functions are handled elsewhere"); 1202 1203 case CK_LValueBitCast: 1204 case CK_ObjCObjectLValueCast: { 1205 Value *V = EmitLValue(E).getAddress(); 1206 V = Builder.CreateBitCast(V, 1207 ConvertType(CGF.getContext().getPointerType(DestTy))); 1208 return EmitLoadOfLValue(CGF.MakeNaturalAlignAddrLValue(V, DestTy)); 1209 } 1210 1211 case CK_CPointerToObjCPointerCast: 1212 case CK_BlockPointerToObjCPointerCast: 1213 case CK_AnyPointerToBlockPointerCast: 1214 case CK_BitCast: { 1215 Value *Src = Visit(const_cast<Expr*>(E)); 1216 return Builder.CreateBitCast(Src, ConvertType(DestTy)); 1217 } 1218 case CK_AtomicToNonAtomic: 1219 case CK_NonAtomicToAtomic: 1220 case CK_NoOp: 1221 case CK_UserDefinedConversion: 1222 return Visit(const_cast<Expr*>(E)); 1223 1224 case CK_BaseToDerived: { 1225 const CXXRecordDecl *DerivedClassDecl = DestTy->getPointeeCXXRecordDecl(); 1226 assert(DerivedClassDecl && "BaseToDerived arg isn't a C++ object pointer!"); 1227 1228 llvm::Value *V = Visit(E); 1229 1230 // C++11 [expr.static.cast]p11: Behavior is undefined if a downcast is 1231 // performed and the object is not of the derived type. 1232 if (CGF.SanitizePerformTypeCheck) 1233 CGF.EmitTypeCheck(CodeGenFunction::TCK_DowncastPointer, CE->getExprLoc(), 1234 V, DestTy->getPointeeType()); 1235 1236 return CGF.GetAddressOfDerivedClass(V, DerivedClassDecl, 1237 CE->path_begin(), CE->path_end(), 1238 ShouldNullCheckClassCastValue(CE)); 1239 } 1240 case CK_UncheckedDerivedToBase: 1241 case CK_DerivedToBase: { 1242 const CXXRecordDecl *DerivedClassDecl = 1243 E->getType()->getPointeeCXXRecordDecl(); 1244 assert(DerivedClassDecl && "DerivedToBase arg isn't a C++ object pointer!"); 1245 1246 return CGF.GetAddressOfBaseClass(Visit(E), DerivedClassDecl, 1247 CE->path_begin(), CE->path_end(), 1248 ShouldNullCheckClassCastValue(CE)); 1249 } 1250 case CK_Dynamic: { 1251 Value *V = Visit(const_cast<Expr*>(E)); 1252 const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(CE); 1253 return CGF.EmitDynamicCast(V, DCE); 1254 } 1255 1256 case CK_ArrayToPointerDecay: { 1257 assert(E->getType()->isArrayType() && 1258 "Array to pointer decay must have array source type!"); 1259 1260 Value *V = EmitLValue(E).getAddress(); // Bitfields can't be arrays. 1261 1262 // Note that VLA pointers are always decayed, so we don't need to do 1263 // anything here. 1264 if (!E->getType()->isVariableArrayType()) { 1265 assert(isa<llvm::PointerType>(V->getType()) && "Expected pointer"); 1266 assert(isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType()) 1267 ->getElementType()) && 1268 "Expected pointer to array"); 1269 V = Builder.CreateStructGEP(V, 0, "arraydecay"); 1270 } 1271 1272 // Make sure the array decay ends up being the right type. This matters if 1273 // the array type was of an incomplete type. 1274 return CGF.Builder.CreateBitCast(V, ConvertType(CE->getType())); 1275 } 1276 case CK_FunctionToPointerDecay: 1277 return EmitLValue(E).getAddress(); 1278 1279 case CK_NullToPointer: 1280 if (MustVisitNullValue(E)) 1281 (void) Visit(E); 1282 1283 return llvm::ConstantPointerNull::get( 1284 cast<llvm::PointerType>(ConvertType(DestTy))); 1285 1286 case CK_NullToMemberPointer: { 1287 if (MustVisitNullValue(E)) 1288 (void) Visit(E); 1289 1290 const MemberPointerType *MPT = CE->getType()->getAs<MemberPointerType>(); 1291 return CGF.CGM.getCXXABI().EmitNullMemberPointer(MPT); 1292 } 1293 1294 case CK_ReinterpretMemberPointer: 1295 case CK_BaseToDerivedMemberPointer: 1296 case CK_DerivedToBaseMemberPointer: { 1297 Value *Src = Visit(E); 1298 1299 // Note that the AST doesn't distinguish between checked and 1300 // unchecked member pointer conversions, so we always have to 1301 // implement checked conversions here. This is inefficient when 1302 // actual control flow may be required in order to perform the 1303 // check, which it is for data member pointers (but not member 1304 // function pointers on Itanium and ARM). 1305 return CGF.CGM.getCXXABI().EmitMemberPointerConversion(CGF, CE, Src); 1306 } 1307 1308 case CK_ARCProduceObject: 1309 return CGF.EmitARCRetainScalarExpr(E); 1310 case CK_ARCConsumeObject: 1311 return CGF.EmitObjCConsumeObject(E->getType(), Visit(E)); 1312 case CK_ARCReclaimReturnedObject: { 1313 llvm::Value *value = Visit(E); 1314 value = CGF.EmitARCRetainAutoreleasedReturnValue(value); 1315 return CGF.EmitObjCConsumeObject(E->getType(), value); 1316 } 1317 case CK_ARCExtendBlockObject: 1318 return CGF.EmitARCExtendBlockObject(E); 1319 1320 case CK_CopyAndAutoreleaseBlockObject: 1321 return CGF.EmitBlockCopyAndAutorelease(Visit(E), E->getType()); 1322 1323 case CK_FloatingRealToComplex: 1324 case CK_FloatingComplexCast: 1325 case CK_IntegralRealToComplex: 1326 case CK_IntegralComplexCast: 1327 case CK_IntegralComplexToFloatingComplex: 1328 case CK_FloatingComplexToIntegralComplex: 1329 case CK_ConstructorConversion: 1330 case CK_ToUnion: 1331 llvm_unreachable("scalar cast to non-scalar value"); 1332 1333 case CK_LValueToRValue: 1334 assert(CGF.getContext().hasSameUnqualifiedType(E->getType(), DestTy)); 1335 assert(E->isGLValue() && "lvalue-to-rvalue applied to r-value!"); 1336 return Visit(const_cast<Expr*>(E)); 1337 1338 case CK_IntegralToPointer: { 1339 Value *Src = Visit(const_cast<Expr*>(E)); 1340 1341 // First, convert to the correct width so that we control the kind of 1342 // extension. 1343 llvm::Type *MiddleTy = CGF.IntPtrTy; 1344 bool InputSigned = E->getType()->isSignedIntegerOrEnumerationType(); 1345 llvm::Value* IntResult = 1346 Builder.CreateIntCast(Src, MiddleTy, InputSigned, "conv"); 1347 1348 return Builder.CreateIntToPtr(IntResult, ConvertType(DestTy)); 1349 } 1350 case CK_PointerToIntegral: 1351 assert(!DestTy->isBooleanType() && "bool should use PointerToBool"); 1352 return Builder.CreatePtrToInt(Visit(E), ConvertType(DestTy)); 1353 1354 case CK_ToVoid: { 1355 CGF.EmitIgnoredExpr(E); 1356 return 0; 1357 } 1358 case CK_VectorSplat: { 1359 llvm::Type *DstTy = ConvertType(DestTy); 1360 Value *Elt = Visit(const_cast<Expr*>(E)); 1361 Elt = EmitScalarConversion(Elt, E->getType(), 1362 DestTy->getAs<VectorType>()->getElementType()); 1363 1364 // Splat the element across to all elements 1365 unsigned NumElements = cast<llvm::VectorType>(DstTy)->getNumElements(); 1366 return Builder.CreateVectorSplat(NumElements, Elt, "splat");; 1367 } 1368 1369 case CK_IntegralCast: 1370 case CK_IntegralToFloating: 1371 case CK_FloatingToIntegral: 1372 case CK_FloatingCast: 1373 return EmitScalarConversion(Visit(E), E->getType(), DestTy); 1374 case CK_IntegralToBoolean: 1375 return EmitIntToBoolConversion(Visit(E)); 1376 case CK_PointerToBoolean: 1377 return EmitPointerToBoolConversion(Visit(E)); 1378 case CK_FloatingToBoolean: 1379 return EmitFloatToBoolConversion(Visit(E)); 1380 case CK_MemberPointerToBoolean: { 1381 llvm::Value *MemPtr = Visit(E); 1382 const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>(); 1383 return CGF.CGM.getCXXABI().EmitMemberPointerIsNotNull(CGF, MemPtr, MPT); 1384 } 1385 1386 case CK_FloatingComplexToReal: 1387 case CK_IntegralComplexToReal: 1388 return CGF.EmitComplexExpr(E, false, true).first; 1389 1390 case CK_FloatingComplexToBoolean: 1391 case CK_IntegralComplexToBoolean: { 1392 CodeGenFunction::ComplexPairTy V = CGF.EmitComplexExpr(E); 1393 1394 // TODO: kill this function off, inline appropriate case here 1395 return EmitComplexToScalarConversion(V, E->getType(), DestTy); 1396 } 1397 1398 case CK_ZeroToOCLEvent: { 1399 assert(DestTy->isEventT() && "CK_ZeroToOCLEvent cast on non event type"); 1400 return llvm::Constant::getNullValue(ConvertType(DestTy)); 1401 } 1402 1403 } 1404 1405 llvm_unreachable("unknown scalar cast"); 1406 } 1407 1408 Value *ScalarExprEmitter::VisitStmtExpr(const StmtExpr *E) { 1409 CodeGenFunction::StmtExprEvaluation eval(CGF); 1410 return CGF.EmitCompoundStmt(*E->getSubStmt(), !E->getType()->isVoidType()) 1411 .getScalarVal(); 1412 } 1413 1414 //===----------------------------------------------------------------------===// 1415 // Unary Operators 1416 //===----------------------------------------------------------------------===// 1417 1418 llvm::Value *ScalarExprEmitter:: 1419 EmitAddConsiderOverflowBehavior(const UnaryOperator *E, 1420 llvm::Value *InVal, 1421 llvm::Value *NextVal, bool IsInc) { 1422 switch (CGF.getLangOpts().getSignedOverflowBehavior()) { 1423 case LangOptions::SOB_Defined: 1424 return Builder.CreateAdd(InVal, NextVal, IsInc ? "inc" : "dec"); 1425 case LangOptions::SOB_Undefined: 1426 if (!CGF.SanOpts->SignedIntegerOverflow) 1427 return Builder.CreateNSWAdd(InVal, NextVal, IsInc ? "inc" : "dec"); 1428 // Fall through. 1429 case LangOptions::SOB_Trapping: 1430 BinOpInfo BinOp; 1431 BinOp.LHS = InVal; 1432 BinOp.RHS = NextVal; 1433 BinOp.Ty = E->getType(); 1434 BinOp.Opcode = BO_Add; 1435 BinOp.FPContractable = false; 1436 BinOp.E = E; 1437 return EmitOverflowCheckedBinOp(BinOp); 1438 } 1439 llvm_unreachable("Unknown SignedOverflowBehaviorTy"); 1440 } 1441 1442 llvm::Value * 1443 ScalarExprEmitter::EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 1444 bool isInc, bool isPre) { 1445 1446 QualType type = E->getSubExpr()->getType(); 1447 llvm::PHINode *atomicPHI = 0; 1448 llvm::Value *value; 1449 llvm::Value *input; 1450 1451 int amount = (isInc ? 1 : -1); 1452 1453 if (const AtomicType *atomicTy = type->getAs<AtomicType>()) { 1454 type = atomicTy->getValueType(); 1455 if (isInc && type->isBooleanType()) { 1456 llvm::Value *True = CGF.EmitToMemory(Builder.getTrue(), type); 1457 if (isPre) { 1458 Builder.Insert(new llvm::StoreInst(True, 1459 LV.getAddress(), LV.isVolatileQualified(), 1460 LV.getAlignment().getQuantity(), 1461 llvm::SequentiallyConsistent)); 1462 return Builder.getTrue(); 1463 } 1464 // For atomic bool increment, we just store true and return it for 1465 // preincrement, do an atomic swap with true for postincrement 1466 return Builder.CreateAtomicRMW(llvm::AtomicRMWInst::Xchg, 1467 LV.getAddress(), True, llvm::SequentiallyConsistent); 1468 } 1469 // Special case for atomic increment / decrement on integers, emit 1470 // atomicrmw instructions. We skip this if we want to be doing overflow 1471 // checking, and fall into the slow path with the atomic cmpxchg loop. 1472 if (!type->isBooleanType() && type->isIntegerType() && 1473 !(type->isUnsignedIntegerType() && 1474 CGF.SanOpts->UnsignedIntegerOverflow) && 1475 CGF.getLangOpts().getSignedOverflowBehavior() != 1476 LangOptions::SOB_Trapping) { 1477 llvm::AtomicRMWInst::BinOp aop = isInc ? llvm::AtomicRMWInst::Add : 1478 llvm::AtomicRMWInst::Sub; 1479 llvm::Instruction::BinaryOps op = isInc ? llvm::Instruction::Add : 1480 llvm::Instruction::Sub; 1481 llvm::Value *amt = CGF.EmitToMemory( 1482 llvm::ConstantInt::get(ConvertType(type), 1, true), type); 1483 llvm::Value *old = Builder.CreateAtomicRMW(aop, 1484 LV.getAddress(), amt, llvm::SequentiallyConsistent); 1485 return isPre ? Builder.CreateBinOp(op, old, amt) : old; 1486 } 1487 value = EmitLoadOfLValue(LV); 1488 input = value; 1489 // For every other atomic operation, we need to emit a load-op-cmpxchg loop 1490 llvm::BasicBlock *startBB = Builder.GetInsertBlock(); 1491 llvm::BasicBlock *opBB = CGF.createBasicBlock("atomic_op", CGF.CurFn); 1492 value = CGF.EmitToMemory(value, type); 1493 Builder.CreateBr(opBB); 1494 Builder.SetInsertPoint(opBB); 1495 atomicPHI = Builder.CreatePHI(value->getType(), 2); 1496 atomicPHI->addIncoming(value, startBB); 1497 value = atomicPHI; 1498 } else { 1499 value = EmitLoadOfLValue(LV); 1500 input = value; 1501 } 1502 1503 // Special case of integer increment that we have to check first: bool++. 1504 // Due to promotion rules, we get: 1505 // bool++ -> bool = bool + 1 1506 // -> bool = (int)bool + 1 1507 // -> bool = ((int)bool + 1 != 0) 1508 // An interesting aspect of this is that increment is always true. 1509 // Decrement does not have this property. 1510 if (isInc && type->isBooleanType()) { 1511 value = Builder.getTrue(); 1512 1513 // Most common case by far: integer increment. 1514 } else if (type->isIntegerType()) { 1515 1516 llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount, true); 1517 1518 // Note that signed integer inc/dec with width less than int can't 1519 // overflow because of promotion rules; we're just eliding a few steps here. 1520 if (value->getType()->getPrimitiveSizeInBits() >= 1521 CGF.IntTy->getBitWidth() && 1522 type->isSignedIntegerOrEnumerationType()) { 1523 value = EmitAddConsiderOverflowBehavior(E, value, amt, isInc); 1524 } else if (value->getType()->getPrimitiveSizeInBits() >= 1525 CGF.IntTy->getBitWidth() && type->isUnsignedIntegerType() && 1526 CGF.SanOpts->UnsignedIntegerOverflow) { 1527 BinOpInfo BinOp; 1528 BinOp.LHS = value; 1529 BinOp.RHS = llvm::ConstantInt::get(value->getType(), 1, false); 1530 BinOp.Ty = E->getType(); 1531 BinOp.Opcode = isInc ? BO_Add : BO_Sub; 1532 BinOp.FPContractable = false; 1533 BinOp.E = E; 1534 value = EmitOverflowCheckedBinOp(BinOp); 1535 } else 1536 value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec"); 1537 1538 // Next most common: pointer increment. 1539 } else if (const PointerType *ptr = type->getAs<PointerType>()) { 1540 QualType type = ptr->getPointeeType(); 1541 1542 // VLA types don't have constant size. 1543 if (const VariableArrayType *vla 1544 = CGF.getContext().getAsVariableArrayType(type)) { 1545 llvm::Value *numElts = CGF.getVLASize(vla).first; 1546 if (!isInc) numElts = Builder.CreateNSWNeg(numElts, "vla.negsize"); 1547 if (CGF.getLangOpts().isSignedOverflowDefined()) 1548 value = Builder.CreateGEP(value, numElts, "vla.inc"); 1549 else 1550 value = Builder.CreateInBoundsGEP(value, numElts, "vla.inc"); 1551 1552 // Arithmetic on function pointers (!) is just +-1. 1553 } else if (type->isFunctionType()) { 1554 llvm::Value *amt = Builder.getInt32(amount); 1555 1556 value = CGF.EmitCastToVoidPtr(value); 1557 if (CGF.getLangOpts().isSignedOverflowDefined()) 1558 value = Builder.CreateGEP(value, amt, "incdec.funcptr"); 1559 else 1560 value = Builder.CreateInBoundsGEP(value, amt, "incdec.funcptr"); 1561 value = Builder.CreateBitCast(value, input->getType()); 1562 1563 // For everything else, we can just do a simple increment. 1564 } else { 1565 llvm::Value *amt = Builder.getInt32(amount); 1566 if (CGF.getLangOpts().isSignedOverflowDefined()) 1567 value = Builder.CreateGEP(value, amt, "incdec.ptr"); 1568 else 1569 value = Builder.CreateInBoundsGEP(value, amt, "incdec.ptr"); 1570 } 1571 1572 // Vector increment/decrement. 1573 } else if (type->isVectorType()) { 1574 if (type->hasIntegerRepresentation()) { 1575 llvm::Value *amt = llvm::ConstantInt::get(value->getType(), amount); 1576 1577 value = Builder.CreateAdd(value, amt, isInc ? "inc" : "dec"); 1578 } else { 1579 value = Builder.CreateFAdd( 1580 value, 1581 llvm::ConstantFP::get(value->getType(), amount), 1582 isInc ? "inc" : "dec"); 1583 } 1584 1585 // Floating point. 1586 } else if (type->isRealFloatingType()) { 1587 // Add the inc/dec to the real part. 1588 llvm::Value *amt; 1589 1590 if (type->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) { 1591 // Another special case: half FP increment should be done via float 1592 value = 1593 Builder.CreateCall(CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_from_fp16), 1594 input); 1595 } 1596 1597 if (value->getType()->isFloatTy()) 1598 amt = llvm::ConstantFP::get(VMContext, 1599 llvm::APFloat(static_cast<float>(amount))); 1600 else if (value->getType()->isDoubleTy()) 1601 amt = llvm::ConstantFP::get(VMContext, 1602 llvm::APFloat(static_cast<double>(amount))); 1603 else { 1604 llvm::APFloat F(static_cast<float>(amount)); 1605 bool ignored; 1606 F.convert(CGF.Target.getLongDoubleFormat(), llvm::APFloat::rmTowardZero, 1607 &ignored); 1608 amt = llvm::ConstantFP::get(VMContext, F); 1609 } 1610 value = Builder.CreateFAdd(value, amt, isInc ? "inc" : "dec"); 1611 1612 if (type->isHalfType() && !CGF.getContext().getLangOpts().NativeHalfType) 1613 value = 1614 Builder.CreateCall(CGF.CGM.getIntrinsic(llvm::Intrinsic::convert_to_fp16), 1615 value); 1616 1617 // Objective-C pointer types. 1618 } else { 1619 const ObjCObjectPointerType *OPT = type->castAs<ObjCObjectPointerType>(); 1620 value = CGF.EmitCastToVoidPtr(value); 1621 1622 CharUnits size = CGF.getContext().getTypeSizeInChars(OPT->getObjectType()); 1623 if (!isInc) size = -size; 1624 llvm::Value *sizeValue = 1625 llvm::ConstantInt::get(CGF.SizeTy, size.getQuantity()); 1626 1627 if (CGF.getLangOpts().isSignedOverflowDefined()) 1628 value = Builder.CreateGEP(value, sizeValue, "incdec.objptr"); 1629 else 1630 value = Builder.CreateInBoundsGEP(value, sizeValue, "incdec.objptr"); 1631 value = Builder.CreateBitCast(value, input->getType()); 1632 } 1633 1634 if (atomicPHI) { 1635 llvm::BasicBlock *opBB = Builder.GetInsertBlock(); 1636 llvm::BasicBlock *contBB = CGF.createBasicBlock("atomic_cont", CGF.CurFn); 1637 llvm::Value *old = Builder.CreateAtomicCmpXchg(LV.getAddress(), atomicPHI, 1638 CGF.EmitToMemory(value, type), llvm::SequentiallyConsistent); 1639 atomicPHI->addIncoming(old, opBB); 1640 llvm::Value *success = Builder.CreateICmpEQ(old, atomicPHI); 1641 Builder.CreateCondBr(success, contBB, opBB); 1642 Builder.SetInsertPoint(contBB); 1643 return isPre ? value : input; 1644 } 1645 1646 // Store the updated result through the lvalue. 1647 if (LV.isBitField()) 1648 CGF.EmitStoreThroughBitfieldLValue(RValue::get(value), LV, &value); 1649 else 1650 CGF.EmitStoreThroughLValue(RValue::get(value), LV); 1651 1652 // If this is a postinc, return the value read from memory, otherwise use the 1653 // updated value. 1654 return isPre ? value : input; 1655 } 1656 1657 1658 1659 Value *ScalarExprEmitter::VisitUnaryMinus(const UnaryOperator *E) { 1660 TestAndClearIgnoreResultAssign(); 1661 // Emit unary minus with EmitSub so we handle overflow cases etc. 1662 BinOpInfo BinOp; 1663 BinOp.RHS = Visit(E->getSubExpr()); 1664 1665 if (BinOp.RHS->getType()->isFPOrFPVectorTy()) 1666 BinOp.LHS = llvm::ConstantFP::getZeroValueForNegation(BinOp.RHS->getType()); 1667 else 1668 BinOp.LHS = llvm::Constant::getNullValue(BinOp.RHS->getType()); 1669 BinOp.Ty = E->getType(); 1670 BinOp.Opcode = BO_Sub; 1671 BinOp.FPContractable = false; 1672 BinOp.E = E; 1673 return EmitSub(BinOp); 1674 } 1675 1676 Value *ScalarExprEmitter::VisitUnaryNot(const UnaryOperator *E) { 1677 TestAndClearIgnoreResultAssign(); 1678 Value *Op = Visit(E->getSubExpr()); 1679 return Builder.CreateNot(Op, "neg"); 1680 } 1681 1682 Value *ScalarExprEmitter::VisitUnaryLNot(const UnaryOperator *E) { 1683 // Perform vector logical not on comparison with zero vector. 1684 if (E->getType()->isExtVectorType()) { 1685 Value *Oper = Visit(E->getSubExpr()); 1686 Value *Zero = llvm::Constant::getNullValue(Oper->getType()); 1687 Value *Result; 1688 if (Oper->getType()->isFPOrFPVectorTy()) 1689 Result = Builder.CreateFCmp(llvm::CmpInst::FCMP_OEQ, Oper, Zero, "cmp"); 1690 else 1691 Result = Builder.CreateICmp(llvm::CmpInst::ICMP_EQ, Oper, Zero, "cmp"); 1692 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext"); 1693 } 1694 1695 // Compare operand to zero. 1696 Value *BoolVal = CGF.EvaluateExprAsBool(E->getSubExpr()); 1697 1698 // Invert value. 1699 // TODO: Could dynamically modify easy computations here. For example, if 1700 // the operand is an icmp ne, turn into icmp eq. 1701 BoolVal = Builder.CreateNot(BoolVal, "lnot"); 1702 1703 // ZExt result to the expr type. 1704 return Builder.CreateZExt(BoolVal, ConvertType(E->getType()), "lnot.ext"); 1705 } 1706 1707 Value *ScalarExprEmitter::VisitOffsetOfExpr(OffsetOfExpr *E) { 1708 // Try folding the offsetof to a constant. 1709 llvm::APSInt Value; 1710 if (E->EvaluateAsInt(Value, CGF.getContext())) 1711 return Builder.getInt(Value); 1712 1713 // Loop over the components of the offsetof to compute the value. 1714 unsigned n = E->getNumComponents(); 1715 llvm::Type* ResultType = ConvertType(E->getType()); 1716 llvm::Value* Result = llvm::Constant::getNullValue(ResultType); 1717 QualType CurrentType = E->getTypeSourceInfo()->getType(); 1718 for (unsigned i = 0; i != n; ++i) { 1719 OffsetOfExpr::OffsetOfNode ON = E->getComponent(i); 1720 llvm::Value *Offset = 0; 1721 switch (ON.getKind()) { 1722 case OffsetOfExpr::OffsetOfNode::Array: { 1723 // Compute the index 1724 Expr *IdxExpr = E->getIndexExpr(ON.getArrayExprIndex()); 1725 llvm::Value* Idx = CGF.EmitScalarExpr(IdxExpr); 1726 bool IdxSigned = IdxExpr->getType()->isSignedIntegerOrEnumerationType(); 1727 Idx = Builder.CreateIntCast(Idx, ResultType, IdxSigned, "conv"); 1728 1729 // Save the element type 1730 CurrentType = 1731 CGF.getContext().getAsArrayType(CurrentType)->getElementType(); 1732 1733 // Compute the element size 1734 llvm::Value* ElemSize = llvm::ConstantInt::get(ResultType, 1735 CGF.getContext().getTypeSizeInChars(CurrentType).getQuantity()); 1736 1737 // Multiply out to compute the result 1738 Offset = Builder.CreateMul(Idx, ElemSize); 1739 break; 1740 } 1741 1742 case OffsetOfExpr::OffsetOfNode::Field: { 1743 FieldDecl *MemberDecl = ON.getField(); 1744 RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl(); 1745 const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD); 1746 1747 // Compute the index of the field in its parent. 1748 unsigned i = 0; 1749 // FIXME: It would be nice if we didn't have to loop here! 1750 for (RecordDecl::field_iterator Field = RD->field_begin(), 1751 FieldEnd = RD->field_end(); 1752 Field != FieldEnd; ++Field, ++i) { 1753 if (*Field == MemberDecl) 1754 break; 1755 } 1756 assert(i < RL.getFieldCount() && "offsetof field in wrong type"); 1757 1758 // Compute the offset to the field 1759 int64_t OffsetInt = RL.getFieldOffset(i) / 1760 CGF.getContext().getCharWidth(); 1761 Offset = llvm::ConstantInt::get(ResultType, OffsetInt); 1762 1763 // Save the element type. 1764 CurrentType = MemberDecl->getType(); 1765 break; 1766 } 1767 1768 case OffsetOfExpr::OffsetOfNode::Identifier: 1769 llvm_unreachable("dependent __builtin_offsetof"); 1770 1771 case OffsetOfExpr::OffsetOfNode::Base: { 1772 if (ON.getBase()->isVirtual()) { 1773 CGF.ErrorUnsupported(E, "virtual base in offsetof"); 1774 continue; 1775 } 1776 1777 RecordDecl *RD = CurrentType->getAs<RecordType>()->getDecl(); 1778 const ASTRecordLayout &RL = CGF.getContext().getASTRecordLayout(RD); 1779 1780 // Save the element type. 1781 CurrentType = ON.getBase()->getType(); 1782 1783 // Compute the offset to the base. 1784 const RecordType *BaseRT = CurrentType->getAs<RecordType>(); 1785 CXXRecordDecl *BaseRD = cast<CXXRecordDecl>(BaseRT->getDecl()); 1786 CharUnits OffsetInt = RL.getBaseClassOffset(BaseRD); 1787 Offset = llvm::ConstantInt::get(ResultType, OffsetInt.getQuantity()); 1788 break; 1789 } 1790 } 1791 Result = Builder.CreateAdd(Result, Offset); 1792 } 1793 return Result; 1794 } 1795 1796 /// VisitUnaryExprOrTypeTraitExpr - Return the size or alignment of the type of 1797 /// argument of the sizeof expression as an integer. 1798 Value * 1799 ScalarExprEmitter::VisitUnaryExprOrTypeTraitExpr( 1800 const UnaryExprOrTypeTraitExpr *E) { 1801 QualType TypeToSize = E->getTypeOfArgument(); 1802 if (E->getKind() == UETT_SizeOf) { 1803 if (const VariableArrayType *VAT = 1804 CGF.getContext().getAsVariableArrayType(TypeToSize)) { 1805 if (E->isArgumentType()) { 1806 // sizeof(type) - make sure to emit the VLA size. 1807 CGF.EmitVariablyModifiedType(TypeToSize); 1808 } else { 1809 // C99 6.5.3.4p2: If the argument is an expression of type 1810 // VLA, it is evaluated. 1811 CGF.EmitIgnoredExpr(E->getArgumentExpr()); 1812 } 1813 1814 QualType eltType; 1815 llvm::Value *numElts; 1816 llvm::tie(numElts, eltType) = CGF.getVLASize(VAT); 1817 1818 llvm::Value *size = numElts; 1819 1820 // Scale the number of non-VLA elements by the non-VLA element size. 1821 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType); 1822 if (!eltSize.isOne()) 1823 size = CGF.Builder.CreateNUWMul(CGF.CGM.getSize(eltSize), numElts); 1824 1825 return size; 1826 } 1827 } 1828 1829 // If this isn't sizeof(vla), the result must be constant; use the constant 1830 // folding logic so we don't have to duplicate it here. 1831 return Builder.getInt(E->EvaluateKnownConstInt(CGF.getContext())); 1832 } 1833 1834 Value *ScalarExprEmitter::VisitUnaryReal(const UnaryOperator *E) { 1835 Expr *Op = E->getSubExpr(); 1836 if (Op->getType()->isAnyComplexType()) { 1837 // If it's an l-value, load through the appropriate subobject l-value. 1838 // Note that we have to ask E because Op might be an l-value that 1839 // this won't work for, e.g. an Obj-C property. 1840 if (E->isGLValue()) 1841 return CGF.EmitLoadOfLValue(CGF.EmitLValue(E)).getScalarVal(); 1842 1843 // Otherwise, calculate and project. 1844 return CGF.EmitComplexExpr(Op, false, true).first; 1845 } 1846 1847 return Visit(Op); 1848 } 1849 1850 Value *ScalarExprEmitter::VisitUnaryImag(const UnaryOperator *E) { 1851 Expr *Op = E->getSubExpr(); 1852 if (Op->getType()->isAnyComplexType()) { 1853 // If it's an l-value, load through the appropriate subobject l-value. 1854 // Note that we have to ask E because Op might be an l-value that 1855 // this won't work for, e.g. an Obj-C property. 1856 if (Op->isGLValue()) 1857 return CGF.EmitLoadOfLValue(CGF.EmitLValue(E)).getScalarVal(); 1858 1859 // Otherwise, calculate and project. 1860 return CGF.EmitComplexExpr(Op, true, false).second; 1861 } 1862 1863 // __imag on a scalar returns zero. Emit the subexpr to ensure side 1864 // effects are evaluated, but not the actual value. 1865 if (Op->isGLValue()) 1866 CGF.EmitLValue(Op); 1867 else 1868 CGF.EmitScalarExpr(Op, true); 1869 return llvm::Constant::getNullValue(ConvertType(E->getType())); 1870 } 1871 1872 //===----------------------------------------------------------------------===// 1873 // Binary Operators 1874 //===----------------------------------------------------------------------===// 1875 1876 BinOpInfo ScalarExprEmitter::EmitBinOps(const BinaryOperator *E) { 1877 TestAndClearIgnoreResultAssign(); 1878 BinOpInfo Result; 1879 Result.LHS = Visit(E->getLHS()); 1880 Result.RHS = Visit(E->getRHS()); 1881 Result.Ty = E->getType(); 1882 Result.Opcode = E->getOpcode(); 1883 Result.FPContractable = E->isFPContractable(); 1884 Result.E = E; 1885 return Result; 1886 } 1887 1888 LValue ScalarExprEmitter::EmitCompoundAssignLValue( 1889 const CompoundAssignOperator *E, 1890 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &), 1891 Value *&Result) { 1892 QualType LHSTy = E->getLHS()->getType(); 1893 BinOpInfo OpInfo; 1894 1895 if (E->getComputationResultType()->isAnyComplexType()) { 1896 // This needs to go through the complex expression emitter, but it's a tad 1897 // complicated to do that... I'm leaving it out for now. (Note that we do 1898 // actually need the imaginary part of the RHS for multiplication and 1899 // division.) 1900 CGF.ErrorUnsupported(E, "complex compound assignment"); 1901 Result = llvm::UndefValue::get(CGF.ConvertType(E->getType())); 1902 return LValue(); 1903 } 1904 1905 // Emit the RHS first. __block variables need to have the rhs evaluated 1906 // first, plus this should improve codegen a little. 1907 OpInfo.RHS = Visit(E->getRHS()); 1908 OpInfo.Ty = E->getComputationResultType(); 1909 OpInfo.Opcode = E->getOpcode(); 1910 OpInfo.FPContractable = false; 1911 OpInfo.E = E; 1912 // Load/convert the LHS. 1913 LValue LHSLV = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store); 1914 1915 llvm::PHINode *atomicPHI = 0; 1916 if (const AtomicType *atomicTy = LHSTy->getAs<AtomicType>()) { 1917 QualType type = atomicTy->getValueType(); 1918 if (!type->isBooleanType() && type->isIntegerType() && 1919 !(type->isUnsignedIntegerType() && 1920 CGF.SanOpts->UnsignedIntegerOverflow) && 1921 CGF.getLangOpts().getSignedOverflowBehavior() != 1922 LangOptions::SOB_Trapping) { 1923 llvm::AtomicRMWInst::BinOp aop = llvm::AtomicRMWInst::BAD_BINOP; 1924 switch (OpInfo.Opcode) { 1925 // We don't have atomicrmw operands for *, %, /, <<, >> 1926 case BO_MulAssign: case BO_DivAssign: 1927 case BO_RemAssign: 1928 case BO_ShlAssign: 1929 case BO_ShrAssign: 1930 break; 1931 case BO_AddAssign: 1932 aop = llvm::AtomicRMWInst::Add; 1933 break; 1934 case BO_SubAssign: 1935 aop = llvm::AtomicRMWInst::Sub; 1936 break; 1937 case BO_AndAssign: 1938 aop = llvm::AtomicRMWInst::And; 1939 break; 1940 case BO_XorAssign: 1941 aop = llvm::AtomicRMWInst::Xor; 1942 break; 1943 case BO_OrAssign: 1944 aop = llvm::AtomicRMWInst::Or; 1945 break; 1946 default: 1947 llvm_unreachable("Invalid compound assignment type"); 1948 } 1949 if (aop != llvm::AtomicRMWInst::BAD_BINOP) { 1950 llvm::Value *amt = CGF.EmitToMemory(EmitScalarConversion(OpInfo.RHS, 1951 E->getRHS()->getType(), LHSTy), LHSTy); 1952 Builder.CreateAtomicRMW(aop, LHSLV.getAddress(), amt, 1953 llvm::SequentiallyConsistent); 1954 return LHSLV; 1955 } 1956 } 1957 // FIXME: For floating point types, we should be saving and restoring the 1958 // floating point environment in the loop. 1959 llvm::BasicBlock *startBB = Builder.GetInsertBlock(); 1960 llvm::BasicBlock *opBB = CGF.createBasicBlock("atomic_op", CGF.CurFn); 1961 OpInfo.LHS = EmitLoadOfLValue(LHSLV); 1962 OpInfo.LHS = CGF.EmitToMemory(OpInfo.LHS, type); 1963 Builder.CreateBr(opBB); 1964 Builder.SetInsertPoint(opBB); 1965 atomicPHI = Builder.CreatePHI(OpInfo.LHS->getType(), 2); 1966 atomicPHI->addIncoming(OpInfo.LHS, startBB); 1967 OpInfo.LHS = atomicPHI; 1968 } 1969 else 1970 OpInfo.LHS = EmitLoadOfLValue(LHSLV); 1971 1972 OpInfo.LHS = EmitScalarConversion(OpInfo.LHS, LHSTy, 1973 E->getComputationLHSType()); 1974 1975 // Expand the binary operator. 1976 Result = (this->*Func)(OpInfo); 1977 1978 // Convert the result back to the LHS type. 1979 Result = EmitScalarConversion(Result, E->getComputationResultType(), LHSTy); 1980 1981 if (atomicPHI) { 1982 llvm::BasicBlock *opBB = Builder.GetInsertBlock(); 1983 llvm::BasicBlock *contBB = CGF.createBasicBlock("atomic_cont", CGF.CurFn); 1984 llvm::Value *old = Builder.CreateAtomicCmpXchg(LHSLV.getAddress(), atomicPHI, 1985 CGF.EmitToMemory(Result, LHSTy), llvm::SequentiallyConsistent); 1986 atomicPHI->addIncoming(old, opBB); 1987 llvm::Value *success = Builder.CreateICmpEQ(old, atomicPHI); 1988 Builder.CreateCondBr(success, contBB, opBB); 1989 Builder.SetInsertPoint(contBB); 1990 return LHSLV; 1991 } 1992 1993 // Store the result value into the LHS lvalue. Bit-fields are handled 1994 // specially because the result is altered by the store, i.e., [C99 6.5.16p1] 1995 // 'An assignment expression has the value of the left operand after the 1996 // assignment...'. 1997 if (LHSLV.isBitField()) 1998 CGF.EmitStoreThroughBitfieldLValue(RValue::get(Result), LHSLV, &Result); 1999 else 2000 CGF.EmitStoreThroughLValue(RValue::get(Result), LHSLV); 2001 2002 return LHSLV; 2003 } 2004 2005 Value *ScalarExprEmitter::EmitCompoundAssign(const CompoundAssignOperator *E, 2006 Value *(ScalarExprEmitter::*Func)(const BinOpInfo &)) { 2007 bool Ignore = TestAndClearIgnoreResultAssign(); 2008 Value *RHS; 2009 LValue LHS = EmitCompoundAssignLValue(E, Func, RHS); 2010 2011 // If the result is clearly ignored, return now. 2012 if (Ignore) 2013 return 0; 2014 2015 // The result of an assignment in C is the assigned r-value. 2016 if (!CGF.getLangOpts().CPlusPlus) 2017 return RHS; 2018 2019 // If the lvalue is non-volatile, return the computed value of the assignment. 2020 if (!LHS.isVolatileQualified()) 2021 return RHS; 2022 2023 // Otherwise, reload the value. 2024 return EmitLoadOfLValue(LHS); 2025 } 2026 2027 void ScalarExprEmitter::EmitUndefinedBehaviorIntegerDivAndRemCheck( 2028 const BinOpInfo &Ops, llvm::Value *Zero, bool isDiv) { 2029 llvm::Value *Cond = 0; 2030 2031 if (CGF.SanOpts->IntegerDivideByZero) 2032 Cond = Builder.CreateICmpNE(Ops.RHS, Zero); 2033 2034 if (CGF.SanOpts->SignedIntegerOverflow && 2035 Ops.Ty->hasSignedIntegerRepresentation()) { 2036 llvm::IntegerType *Ty = cast<llvm::IntegerType>(Zero->getType()); 2037 2038 llvm::Value *IntMin = 2039 Builder.getInt(llvm::APInt::getSignedMinValue(Ty->getBitWidth())); 2040 llvm::Value *NegOne = llvm::ConstantInt::get(Ty, -1ULL); 2041 2042 llvm::Value *LHSCmp = Builder.CreateICmpNE(Ops.LHS, IntMin); 2043 llvm::Value *RHSCmp = Builder.CreateICmpNE(Ops.RHS, NegOne); 2044 llvm::Value *Overflow = Builder.CreateOr(LHSCmp, RHSCmp, "or"); 2045 Cond = Cond ? Builder.CreateAnd(Cond, Overflow, "and") : Overflow; 2046 } 2047 2048 if (Cond) 2049 EmitBinOpCheck(Cond, Ops); 2050 } 2051 2052 Value *ScalarExprEmitter::EmitDiv(const BinOpInfo &Ops) { 2053 if ((CGF.SanOpts->IntegerDivideByZero || 2054 CGF.SanOpts->SignedIntegerOverflow) && 2055 Ops.Ty->isIntegerType()) { 2056 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty)); 2057 EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, true); 2058 } else if (CGF.SanOpts->FloatDivideByZero && 2059 Ops.Ty->isRealFloatingType()) { 2060 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty)); 2061 EmitBinOpCheck(Builder.CreateFCmpUNE(Ops.RHS, Zero), Ops); 2062 } 2063 2064 if (Ops.LHS->getType()->isFPOrFPVectorTy()) { 2065 llvm::Value *Val = Builder.CreateFDiv(Ops.LHS, Ops.RHS, "div"); 2066 if (CGF.getLangOpts().OpenCL) { 2067 // OpenCL 1.1 7.4: minimum accuracy of single precision / is 2.5ulp 2068 llvm::Type *ValTy = Val->getType(); 2069 if (ValTy->isFloatTy() || 2070 (isa<llvm::VectorType>(ValTy) && 2071 cast<llvm::VectorType>(ValTy)->getElementType()->isFloatTy())) 2072 CGF.SetFPAccuracy(Val, 2.5); 2073 } 2074 return Val; 2075 } 2076 else if (Ops.Ty->hasUnsignedIntegerRepresentation()) 2077 return Builder.CreateUDiv(Ops.LHS, Ops.RHS, "div"); 2078 else 2079 return Builder.CreateSDiv(Ops.LHS, Ops.RHS, "div"); 2080 } 2081 2082 Value *ScalarExprEmitter::EmitRem(const BinOpInfo &Ops) { 2083 // Rem in C can't be a floating point type: C99 6.5.5p2. 2084 if (CGF.SanOpts->IntegerDivideByZero) { 2085 llvm::Value *Zero = llvm::Constant::getNullValue(ConvertType(Ops.Ty)); 2086 2087 if (Ops.Ty->isIntegerType()) 2088 EmitUndefinedBehaviorIntegerDivAndRemCheck(Ops, Zero, false); 2089 } 2090 2091 if (Ops.Ty->hasUnsignedIntegerRepresentation()) 2092 return Builder.CreateURem(Ops.LHS, Ops.RHS, "rem"); 2093 else 2094 return Builder.CreateSRem(Ops.LHS, Ops.RHS, "rem"); 2095 } 2096 2097 Value *ScalarExprEmitter::EmitOverflowCheckedBinOp(const BinOpInfo &Ops) { 2098 unsigned IID; 2099 unsigned OpID = 0; 2100 2101 bool isSigned = Ops.Ty->isSignedIntegerOrEnumerationType(); 2102 switch (Ops.Opcode) { 2103 case BO_Add: 2104 case BO_AddAssign: 2105 OpID = 1; 2106 IID = isSigned ? llvm::Intrinsic::sadd_with_overflow : 2107 llvm::Intrinsic::uadd_with_overflow; 2108 break; 2109 case BO_Sub: 2110 case BO_SubAssign: 2111 OpID = 2; 2112 IID = isSigned ? llvm::Intrinsic::ssub_with_overflow : 2113 llvm::Intrinsic::usub_with_overflow; 2114 break; 2115 case BO_Mul: 2116 case BO_MulAssign: 2117 OpID = 3; 2118 IID = isSigned ? llvm::Intrinsic::smul_with_overflow : 2119 llvm::Intrinsic::umul_with_overflow; 2120 break; 2121 default: 2122 llvm_unreachable("Unsupported operation for overflow detection"); 2123 } 2124 OpID <<= 1; 2125 if (isSigned) 2126 OpID |= 1; 2127 2128 llvm::Type *opTy = CGF.CGM.getTypes().ConvertType(Ops.Ty); 2129 2130 llvm::Function *intrinsic = CGF.CGM.getIntrinsic(IID, opTy); 2131 2132 Value *resultAndOverflow = Builder.CreateCall2(intrinsic, Ops.LHS, Ops.RHS); 2133 Value *result = Builder.CreateExtractValue(resultAndOverflow, 0); 2134 Value *overflow = Builder.CreateExtractValue(resultAndOverflow, 1); 2135 2136 // Handle overflow with llvm.trap if no custom handler has been specified. 2137 const std::string *handlerName = 2138 &CGF.getLangOpts().OverflowHandler; 2139 if (handlerName->empty()) { 2140 // If the signed-integer-overflow sanitizer is enabled, emit a call to its 2141 // runtime. Otherwise, this is a -ftrapv check, so just emit a trap. 2142 if (!isSigned || CGF.SanOpts->SignedIntegerOverflow) 2143 EmitBinOpCheck(Builder.CreateNot(overflow), Ops); 2144 else 2145 CGF.EmitTrapCheck(Builder.CreateNot(overflow)); 2146 return result; 2147 } 2148 2149 // Branch in case of overflow. 2150 llvm::BasicBlock *initialBB = Builder.GetInsertBlock(); 2151 llvm::Function::iterator insertPt = initialBB; 2152 llvm::BasicBlock *continueBB = CGF.createBasicBlock("nooverflow", CGF.CurFn, 2153 llvm::next(insertPt)); 2154 llvm::BasicBlock *overflowBB = CGF.createBasicBlock("overflow", CGF.CurFn); 2155 2156 Builder.CreateCondBr(overflow, overflowBB, continueBB); 2157 2158 // If an overflow handler is set, then we want to call it and then use its 2159 // result, if it returns. 2160 Builder.SetInsertPoint(overflowBB); 2161 2162 // Get the overflow handler. 2163 llvm::Type *Int8Ty = CGF.Int8Ty; 2164 llvm::Type *argTypes[] = { CGF.Int64Ty, CGF.Int64Ty, Int8Ty, Int8Ty }; 2165 llvm::FunctionType *handlerTy = 2166 llvm::FunctionType::get(CGF.Int64Ty, argTypes, true); 2167 llvm::Value *handler = CGF.CGM.CreateRuntimeFunction(handlerTy, *handlerName); 2168 2169 // Sign extend the args to 64-bit, so that we can use the same handler for 2170 // all types of overflow. 2171 llvm::Value *lhs = Builder.CreateSExt(Ops.LHS, CGF.Int64Ty); 2172 llvm::Value *rhs = Builder.CreateSExt(Ops.RHS, CGF.Int64Ty); 2173 2174 // Call the handler with the two arguments, the operation, and the size of 2175 // the result. 2176 llvm::Value *handlerArgs[] = { 2177 lhs, 2178 rhs, 2179 Builder.getInt8(OpID), 2180 Builder.getInt8(cast<llvm::IntegerType>(opTy)->getBitWidth()) 2181 }; 2182 llvm::Value *handlerResult = 2183 CGF.EmitNounwindRuntimeCall(handler, handlerArgs); 2184 2185 // Truncate the result back to the desired size. 2186 handlerResult = Builder.CreateTrunc(handlerResult, opTy); 2187 Builder.CreateBr(continueBB); 2188 2189 Builder.SetInsertPoint(continueBB); 2190 llvm::PHINode *phi = Builder.CreatePHI(opTy, 2); 2191 phi->addIncoming(result, initialBB); 2192 phi->addIncoming(handlerResult, overflowBB); 2193 2194 return phi; 2195 } 2196 2197 /// Emit pointer + index arithmetic. 2198 static Value *emitPointerArithmetic(CodeGenFunction &CGF, 2199 const BinOpInfo &op, 2200 bool isSubtraction) { 2201 // Must have binary (not unary) expr here. Unary pointer 2202 // increment/decrement doesn't use this path. 2203 const BinaryOperator *expr = cast<BinaryOperator>(op.E); 2204 2205 Value *pointer = op.LHS; 2206 Expr *pointerOperand = expr->getLHS(); 2207 Value *index = op.RHS; 2208 Expr *indexOperand = expr->getRHS(); 2209 2210 // In a subtraction, the LHS is always the pointer. 2211 if (!isSubtraction && !pointer->getType()->isPointerTy()) { 2212 std::swap(pointer, index); 2213 std::swap(pointerOperand, indexOperand); 2214 } 2215 2216 unsigned width = cast<llvm::IntegerType>(index->getType())->getBitWidth(); 2217 if (width != CGF.PointerWidthInBits) { 2218 // Zero-extend or sign-extend the pointer value according to 2219 // whether the index is signed or not. 2220 bool isSigned = indexOperand->getType()->isSignedIntegerOrEnumerationType(); 2221 index = CGF.Builder.CreateIntCast(index, CGF.PtrDiffTy, isSigned, 2222 "idx.ext"); 2223 } 2224 2225 // If this is subtraction, negate the index. 2226 if (isSubtraction) 2227 index = CGF.Builder.CreateNeg(index, "idx.neg"); 2228 2229 if (CGF.SanOpts->Bounds) 2230 CGF.EmitBoundsCheck(op.E, pointerOperand, index, indexOperand->getType(), 2231 /*Accessed*/ false); 2232 2233 const PointerType *pointerType 2234 = pointerOperand->getType()->getAs<PointerType>(); 2235 if (!pointerType) { 2236 QualType objectType = pointerOperand->getType() 2237 ->castAs<ObjCObjectPointerType>() 2238 ->getPointeeType(); 2239 llvm::Value *objectSize 2240 = CGF.CGM.getSize(CGF.getContext().getTypeSizeInChars(objectType)); 2241 2242 index = CGF.Builder.CreateMul(index, objectSize); 2243 2244 Value *result = CGF.Builder.CreateBitCast(pointer, CGF.VoidPtrTy); 2245 result = CGF.Builder.CreateGEP(result, index, "add.ptr"); 2246 return CGF.Builder.CreateBitCast(result, pointer->getType()); 2247 } 2248 2249 QualType elementType = pointerType->getPointeeType(); 2250 if (const VariableArrayType *vla 2251 = CGF.getContext().getAsVariableArrayType(elementType)) { 2252 // The element count here is the total number of non-VLA elements. 2253 llvm::Value *numElements = CGF.getVLASize(vla).first; 2254 2255 // Effectively, the multiply by the VLA size is part of the GEP. 2256 // GEP indexes are signed, and scaling an index isn't permitted to 2257 // signed-overflow, so we use the same semantics for our explicit 2258 // multiply. We suppress this if overflow is not undefined behavior. 2259 if (CGF.getLangOpts().isSignedOverflowDefined()) { 2260 index = CGF.Builder.CreateMul(index, numElements, "vla.index"); 2261 pointer = CGF.Builder.CreateGEP(pointer, index, "add.ptr"); 2262 } else { 2263 index = CGF.Builder.CreateNSWMul(index, numElements, "vla.index"); 2264 pointer = CGF.Builder.CreateInBoundsGEP(pointer, index, "add.ptr"); 2265 } 2266 return pointer; 2267 } 2268 2269 // Explicitly handle GNU void* and function pointer arithmetic extensions. The 2270 // GNU void* casts amount to no-ops since our void* type is i8*, but this is 2271 // future proof. 2272 if (elementType->isVoidType() || elementType->isFunctionType()) { 2273 Value *result = CGF.Builder.CreateBitCast(pointer, CGF.VoidPtrTy); 2274 result = CGF.Builder.CreateGEP(result, index, "add.ptr"); 2275 return CGF.Builder.CreateBitCast(result, pointer->getType()); 2276 } 2277 2278 if (CGF.getLangOpts().isSignedOverflowDefined()) 2279 return CGF.Builder.CreateGEP(pointer, index, "add.ptr"); 2280 2281 return CGF.Builder.CreateInBoundsGEP(pointer, index, "add.ptr"); 2282 } 2283 2284 // Construct an fmuladd intrinsic to represent a fused mul-add of MulOp and 2285 // Addend. Use negMul and negAdd to negate the first operand of the Mul or 2286 // the add operand respectively. This allows fmuladd to represent a*b-c, or 2287 // c-a*b. Patterns in LLVM should catch the negated forms and translate them to 2288 // efficient operations. 2289 static Value* buildFMulAdd(llvm::BinaryOperator *MulOp, Value *Addend, 2290 const CodeGenFunction &CGF, CGBuilderTy &Builder, 2291 bool negMul, bool negAdd) { 2292 assert(!(negMul && negAdd) && "Only one of negMul and negAdd should be set."); 2293 2294 Value *MulOp0 = MulOp->getOperand(0); 2295 Value *MulOp1 = MulOp->getOperand(1); 2296 if (negMul) { 2297 MulOp0 = 2298 Builder.CreateFSub( 2299 llvm::ConstantFP::getZeroValueForNegation(MulOp0->getType()), MulOp0, 2300 "neg"); 2301 } else if (negAdd) { 2302 Addend = 2303 Builder.CreateFSub( 2304 llvm::ConstantFP::getZeroValueForNegation(Addend->getType()), Addend, 2305 "neg"); 2306 } 2307 2308 Value *FMulAdd = 2309 Builder.CreateCall3( 2310 CGF.CGM.getIntrinsic(llvm::Intrinsic::fmuladd, Addend->getType()), 2311 MulOp0, MulOp1, Addend); 2312 MulOp->eraseFromParent(); 2313 2314 return FMulAdd; 2315 } 2316 2317 // Check whether it would be legal to emit an fmuladd intrinsic call to 2318 // represent op and if so, build the fmuladd. 2319 // 2320 // Checks that (a) the operation is fusable, and (b) -ffp-contract=on. 2321 // Does NOT check the type of the operation - it's assumed that this function 2322 // will be called from contexts where it's known that the type is contractable. 2323 static Value* tryEmitFMulAdd(const BinOpInfo &op, 2324 const CodeGenFunction &CGF, CGBuilderTy &Builder, 2325 bool isSub=false) { 2326 2327 assert((op.Opcode == BO_Add || op.Opcode == BO_AddAssign || 2328 op.Opcode == BO_Sub || op.Opcode == BO_SubAssign) && 2329 "Only fadd/fsub can be the root of an fmuladd."); 2330 2331 // Check whether this op is marked as fusable. 2332 if (!op.FPContractable) 2333 return 0; 2334 2335 // Check whether -ffp-contract=on. (If -ffp-contract=off/fast, fusing is 2336 // either disabled, or handled entirely by the LLVM backend). 2337 if (CGF.CGM.getCodeGenOpts().getFPContractMode() != CodeGenOptions::FPC_On) 2338 return 0; 2339 2340 // We have a potentially fusable op. Look for a mul on one of the operands. 2341 if (llvm::BinaryOperator* LHSBinOp = dyn_cast<llvm::BinaryOperator>(op.LHS)) { 2342 if (LHSBinOp->getOpcode() == llvm::Instruction::FMul) { 2343 assert(LHSBinOp->getNumUses() == 0 && 2344 "Operations with multiple uses shouldn't be contracted."); 2345 return buildFMulAdd(LHSBinOp, op.RHS, CGF, Builder, false, isSub); 2346 } 2347 } else if (llvm::BinaryOperator* RHSBinOp = 2348 dyn_cast<llvm::BinaryOperator>(op.RHS)) { 2349 if (RHSBinOp->getOpcode() == llvm::Instruction::FMul) { 2350 assert(RHSBinOp->getNumUses() == 0 && 2351 "Operations with multiple uses shouldn't be contracted."); 2352 return buildFMulAdd(RHSBinOp, op.LHS, CGF, Builder, isSub, false); 2353 } 2354 } 2355 2356 return 0; 2357 } 2358 2359 Value *ScalarExprEmitter::EmitAdd(const BinOpInfo &op) { 2360 if (op.LHS->getType()->isPointerTy() || 2361 op.RHS->getType()->isPointerTy()) 2362 return emitPointerArithmetic(CGF, op, /*subtraction*/ false); 2363 2364 if (op.Ty->isSignedIntegerOrEnumerationType()) { 2365 switch (CGF.getLangOpts().getSignedOverflowBehavior()) { 2366 case LangOptions::SOB_Defined: 2367 return Builder.CreateAdd(op.LHS, op.RHS, "add"); 2368 case LangOptions::SOB_Undefined: 2369 if (!CGF.SanOpts->SignedIntegerOverflow) 2370 return Builder.CreateNSWAdd(op.LHS, op.RHS, "add"); 2371 // Fall through. 2372 case LangOptions::SOB_Trapping: 2373 return EmitOverflowCheckedBinOp(op); 2374 } 2375 } 2376 2377 if (op.Ty->isUnsignedIntegerType() && CGF.SanOpts->UnsignedIntegerOverflow) 2378 return EmitOverflowCheckedBinOp(op); 2379 2380 if (op.LHS->getType()->isFPOrFPVectorTy()) { 2381 // Try to form an fmuladd. 2382 if (Value *FMulAdd = tryEmitFMulAdd(op, CGF, Builder)) 2383 return FMulAdd; 2384 2385 return Builder.CreateFAdd(op.LHS, op.RHS, "add"); 2386 } 2387 2388 return Builder.CreateAdd(op.LHS, op.RHS, "add"); 2389 } 2390 2391 Value *ScalarExprEmitter::EmitSub(const BinOpInfo &op) { 2392 // The LHS is always a pointer if either side is. 2393 if (!op.LHS->getType()->isPointerTy()) { 2394 if (op.Ty->isSignedIntegerOrEnumerationType()) { 2395 switch (CGF.getLangOpts().getSignedOverflowBehavior()) { 2396 case LangOptions::SOB_Defined: 2397 return Builder.CreateSub(op.LHS, op.RHS, "sub"); 2398 case LangOptions::SOB_Undefined: 2399 if (!CGF.SanOpts->SignedIntegerOverflow) 2400 return Builder.CreateNSWSub(op.LHS, op.RHS, "sub"); 2401 // Fall through. 2402 case LangOptions::SOB_Trapping: 2403 return EmitOverflowCheckedBinOp(op); 2404 } 2405 } 2406 2407 if (op.Ty->isUnsignedIntegerType() && CGF.SanOpts->UnsignedIntegerOverflow) 2408 return EmitOverflowCheckedBinOp(op); 2409 2410 if (op.LHS->getType()->isFPOrFPVectorTy()) { 2411 // Try to form an fmuladd. 2412 if (Value *FMulAdd = tryEmitFMulAdd(op, CGF, Builder, true)) 2413 return FMulAdd; 2414 return Builder.CreateFSub(op.LHS, op.RHS, "sub"); 2415 } 2416 2417 return Builder.CreateSub(op.LHS, op.RHS, "sub"); 2418 } 2419 2420 // If the RHS is not a pointer, then we have normal pointer 2421 // arithmetic. 2422 if (!op.RHS->getType()->isPointerTy()) 2423 return emitPointerArithmetic(CGF, op, /*subtraction*/ true); 2424 2425 // Otherwise, this is a pointer subtraction. 2426 2427 // Do the raw subtraction part. 2428 llvm::Value *LHS 2429 = Builder.CreatePtrToInt(op.LHS, CGF.PtrDiffTy, "sub.ptr.lhs.cast"); 2430 llvm::Value *RHS 2431 = Builder.CreatePtrToInt(op.RHS, CGF.PtrDiffTy, "sub.ptr.rhs.cast"); 2432 Value *diffInChars = Builder.CreateSub(LHS, RHS, "sub.ptr.sub"); 2433 2434 // Okay, figure out the element size. 2435 const BinaryOperator *expr = cast<BinaryOperator>(op.E); 2436 QualType elementType = expr->getLHS()->getType()->getPointeeType(); 2437 2438 llvm::Value *divisor = 0; 2439 2440 // For a variable-length array, this is going to be non-constant. 2441 if (const VariableArrayType *vla 2442 = CGF.getContext().getAsVariableArrayType(elementType)) { 2443 llvm::Value *numElements; 2444 llvm::tie(numElements, elementType) = CGF.getVLASize(vla); 2445 2446 divisor = numElements; 2447 2448 // Scale the number of non-VLA elements by the non-VLA element size. 2449 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(elementType); 2450 if (!eltSize.isOne()) 2451 divisor = CGF.Builder.CreateNUWMul(CGF.CGM.getSize(eltSize), divisor); 2452 2453 // For everything elese, we can just compute it, safe in the 2454 // assumption that Sema won't let anything through that we can't 2455 // safely compute the size of. 2456 } else { 2457 CharUnits elementSize; 2458 // Handle GCC extension for pointer arithmetic on void* and 2459 // function pointer types. 2460 if (elementType->isVoidType() || elementType->isFunctionType()) 2461 elementSize = CharUnits::One(); 2462 else 2463 elementSize = CGF.getContext().getTypeSizeInChars(elementType); 2464 2465 // Don't even emit the divide for element size of 1. 2466 if (elementSize.isOne()) 2467 return diffInChars; 2468 2469 divisor = CGF.CGM.getSize(elementSize); 2470 } 2471 2472 // Otherwise, do a full sdiv. This uses the "exact" form of sdiv, since 2473 // pointer difference in C is only defined in the case where both operands 2474 // are pointing to elements of an array. 2475 return Builder.CreateExactSDiv(diffInChars, divisor, "sub.ptr.div"); 2476 } 2477 2478 Value *ScalarExprEmitter::GetWidthMinusOneValue(Value* LHS,Value* RHS) { 2479 llvm::IntegerType *Ty; 2480 if (llvm::VectorType *VT = dyn_cast<llvm::VectorType>(LHS->getType())) 2481 Ty = cast<llvm::IntegerType>(VT->getElementType()); 2482 else 2483 Ty = cast<llvm::IntegerType>(LHS->getType()); 2484 return llvm::ConstantInt::get(RHS->getType(), Ty->getBitWidth() - 1); 2485 } 2486 2487 Value *ScalarExprEmitter::EmitShl(const BinOpInfo &Ops) { 2488 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 2489 // RHS to the same size as the LHS. 2490 Value *RHS = Ops.RHS; 2491 if (Ops.LHS->getType() != RHS->getType()) 2492 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 2493 2494 if (CGF.SanOpts->Shift && !CGF.getLangOpts().OpenCL && 2495 isa<llvm::IntegerType>(Ops.LHS->getType())) { 2496 llvm::Value *WidthMinusOne = GetWidthMinusOneValue(Ops.LHS, RHS); 2497 llvm::Value *Valid = Builder.CreateICmpULE(RHS, WidthMinusOne); 2498 2499 if (Ops.Ty->hasSignedIntegerRepresentation()) { 2500 llvm::BasicBlock *Orig = Builder.GetInsertBlock(); 2501 llvm::BasicBlock *Cont = CGF.createBasicBlock("cont"); 2502 llvm::BasicBlock *CheckBitsShifted = CGF.createBasicBlock("check"); 2503 Builder.CreateCondBr(Valid, CheckBitsShifted, Cont); 2504 2505 // Check whether we are shifting any non-zero bits off the top of the 2506 // integer. 2507 CGF.EmitBlock(CheckBitsShifted); 2508 llvm::Value *BitsShiftedOff = 2509 Builder.CreateLShr(Ops.LHS, 2510 Builder.CreateSub(WidthMinusOne, RHS, "shl.zeros", 2511 /*NUW*/true, /*NSW*/true), 2512 "shl.check"); 2513 if (CGF.getLangOpts().CPlusPlus) { 2514 // In C99, we are not permitted to shift a 1 bit into the sign bit. 2515 // Under C++11's rules, shifting a 1 bit into the sign bit is 2516 // OK, but shifting a 1 bit out of it is not. (C89 and C++03 don't 2517 // define signed left shifts, so we use the C99 and C++11 rules there). 2518 llvm::Value *One = llvm::ConstantInt::get(BitsShiftedOff->getType(), 1); 2519 BitsShiftedOff = Builder.CreateLShr(BitsShiftedOff, One); 2520 } 2521 llvm::Value *Zero = llvm::ConstantInt::get(BitsShiftedOff->getType(), 0); 2522 llvm::Value *SecondCheck = Builder.CreateICmpEQ(BitsShiftedOff, Zero); 2523 CGF.EmitBlock(Cont); 2524 llvm::PHINode *P = Builder.CreatePHI(Valid->getType(), 2); 2525 P->addIncoming(Valid, Orig); 2526 P->addIncoming(SecondCheck, CheckBitsShifted); 2527 Valid = P; 2528 } 2529 2530 EmitBinOpCheck(Valid, Ops); 2531 } 2532 // OpenCL 6.3j: shift values are effectively % word size of LHS. 2533 if (CGF.getLangOpts().OpenCL) 2534 RHS = Builder.CreateAnd(RHS, GetWidthMinusOneValue(Ops.LHS, RHS), "shl.mask"); 2535 2536 return Builder.CreateShl(Ops.LHS, RHS, "shl"); 2537 } 2538 2539 Value *ScalarExprEmitter::EmitShr(const BinOpInfo &Ops) { 2540 // LLVM requires the LHS and RHS to be the same type: promote or truncate the 2541 // RHS to the same size as the LHS. 2542 Value *RHS = Ops.RHS; 2543 if (Ops.LHS->getType() != RHS->getType()) 2544 RHS = Builder.CreateIntCast(RHS, Ops.LHS->getType(), false, "sh_prom"); 2545 2546 if (CGF.SanOpts->Shift && !CGF.getLangOpts().OpenCL && 2547 isa<llvm::IntegerType>(Ops.LHS->getType())) 2548 EmitBinOpCheck(Builder.CreateICmpULE(RHS, GetWidthMinusOneValue(Ops.LHS, RHS)), Ops); 2549 2550 // OpenCL 6.3j: shift values are effectively % word size of LHS. 2551 if (CGF.getLangOpts().OpenCL) 2552 RHS = Builder.CreateAnd(RHS, GetWidthMinusOneValue(Ops.LHS, RHS), "shr.mask"); 2553 2554 if (Ops.Ty->hasUnsignedIntegerRepresentation()) 2555 return Builder.CreateLShr(Ops.LHS, RHS, "shr"); 2556 return Builder.CreateAShr(Ops.LHS, RHS, "shr"); 2557 } 2558 2559 enum IntrinsicType { VCMPEQ, VCMPGT }; 2560 // return corresponding comparison intrinsic for given vector type 2561 static llvm::Intrinsic::ID GetIntrinsic(IntrinsicType IT, 2562 BuiltinType::Kind ElemKind) { 2563 switch (ElemKind) { 2564 default: llvm_unreachable("unexpected element type"); 2565 case BuiltinType::Char_U: 2566 case BuiltinType::UChar: 2567 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p : 2568 llvm::Intrinsic::ppc_altivec_vcmpgtub_p; 2569 case BuiltinType::Char_S: 2570 case BuiltinType::SChar: 2571 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequb_p : 2572 llvm::Intrinsic::ppc_altivec_vcmpgtsb_p; 2573 case BuiltinType::UShort: 2574 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p : 2575 llvm::Intrinsic::ppc_altivec_vcmpgtuh_p; 2576 case BuiltinType::Short: 2577 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequh_p : 2578 llvm::Intrinsic::ppc_altivec_vcmpgtsh_p; 2579 case BuiltinType::UInt: 2580 case BuiltinType::ULong: 2581 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p : 2582 llvm::Intrinsic::ppc_altivec_vcmpgtuw_p; 2583 case BuiltinType::Int: 2584 case BuiltinType::Long: 2585 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpequw_p : 2586 llvm::Intrinsic::ppc_altivec_vcmpgtsw_p; 2587 case BuiltinType::Float: 2588 return (IT == VCMPEQ) ? llvm::Intrinsic::ppc_altivec_vcmpeqfp_p : 2589 llvm::Intrinsic::ppc_altivec_vcmpgtfp_p; 2590 } 2591 } 2592 2593 Value *ScalarExprEmitter::EmitCompare(const BinaryOperator *E,unsigned UICmpOpc, 2594 unsigned SICmpOpc, unsigned FCmpOpc) { 2595 TestAndClearIgnoreResultAssign(); 2596 Value *Result; 2597 QualType LHSTy = E->getLHS()->getType(); 2598 if (const MemberPointerType *MPT = LHSTy->getAs<MemberPointerType>()) { 2599 assert(E->getOpcode() == BO_EQ || 2600 E->getOpcode() == BO_NE); 2601 Value *LHS = CGF.EmitScalarExpr(E->getLHS()); 2602 Value *RHS = CGF.EmitScalarExpr(E->getRHS()); 2603 Result = CGF.CGM.getCXXABI().EmitMemberPointerComparison( 2604 CGF, LHS, RHS, MPT, E->getOpcode() == BO_NE); 2605 } else if (!LHSTy->isAnyComplexType()) { 2606 Value *LHS = Visit(E->getLHS()); 2607 Value *RHS = Visit(E->getRHS()); 2608 2609 // If AltiVec, the comparison results in a numeric type, so we use 2610 // intrinsics comparing vectors and giving 0 or 1 as a result 2611 if (LHSTy->isVectorType() && !E->getType()->isVectorType()) { 2612 // constants for mapping CR6 register bits to predicate result 2613 enum { CR6_EQ=0, CR6_EQ_REV, CR6_LT, CR6_LT_REV } CR6; 2614 2615 llvm::Intrinsic::ID ID = llvm::Intrinsic::not_intrinsic; 2616 2617 // in several cases vector arguments order will be reversed 2618 Value *FirstVecArg = LHS, 2619 *SecondVecArg = RHS; 2620 2621 QualType ElTy = LHSTy->getAs<VectorType>()->getElementType(); 2622 const BuiltinType *BTy = ElTy->getAs<BuiltinType>(); 2623 BuiltinType::Kind ElementKind = BTy->getKind(); 2624 2625 switch(E->getOpcode()) { 2626 default: llvm_unreachable("is not a comparison operation"); 2627 case BO_EQ: 2628 CR6 = CR6_LT; 2629 ID = GetIntrinsic(VCMPEQ, ElementKind); 2630 break; 2631 case BO_NE: 2632 CR6 = CR6_EQ; 2633 ID = GetIntrinsic(VCMPEQ, ElementKind); 2634 break; 2635 case BO_LT: 2636 CR6 = CR6_LT; 2637 ID = GetIntrinsic(VCMPGT, ElementKind); 2638 std::swap(FirstVecArg, SecondVecArg); 2639 break; 2640 case BO_GT: 2641 CR6 = CR6_LT; 2642 ID = GetIntrinsic(VCMPGT, ElementKind); 2643 break; 2644 case BO_LE: 2645 if (ElementKind == BuiltinType::Float) { 2646 CR6 = CR6_LT; 2647 ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p; 2648 std::swap(FirstVecArg, SecondVecArg); 2649 } 2650 else { 2651 CR6 = CR6_EQ; 2652 ID = GetIntrinsic(VCMPGT, ElementKind); 2653 } 2654 break; 2655 case BO_GE: 2656 if (ElementKind == BuiltinType::Float) { 2657 CR6 = CR6_LT; 2658 ID = llvm::Intrinsic::ppc_altivec_vcmpgefp_p; 2659 } 2660 else { 2661 CR6 = CR6_EQ; 2662 ID = GetIntrinsic(VCMPGT, ElementKind); 2663 std::swap(FirstVecArg, SecondVecArg); 2664 } 2665 break; 2666 } 2667 2668 Value *CR6Param = Builder.getInt32(CR6); 2669 llvm::Function *F = CGF.CGM.getIntrinsic(ID); 2670 Result = Builder.CreateCall3(F, CR6Param, FirstVecArg, SecondVecArg, ""); 2671 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 2672 } 2673 2674 if (LHS->getType()->isFPOrFPVectorTy()) { 2675 Result = Builder.CreateFCmp((llvm::CmpInst::Predicate)FCmpOpc, 2676 LHS, RHS, "cmp"); 2677 } else if (LHSTy->hasSignedIntegerRepresentation()) { 2678 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc, 2679 LHS, RHS, "cmp"); 2680 } else { 2681 // Unsigned integers and pointers. 2682 Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2683 LHS, RHS, "cmp"); 2684 } 2685 2686 // If this is a vector comparison, sign extend the result to the appropriate 2687 // vector integer type and return it (don't convert to bool). 2688 if (LHSTy->isVectorType()) 2689 return Builder.CreateSExt(Result, ConvertType(E->getType()), "sext"); 2690 2691 } else { 2692 // Complex Comparison: can only be an equality comparison. 2693 CodeGenFunction::ComplexPairTy LHS = CGF.EmitComplexExpr(E->getLHS()); 2694 CodeGenFunction::ComplexPairTy RHS = CGF.EmitComplexExpr(E->getRHS()); 2695 2696 QualType CETy = LHSTy->getAs<ComplexType>()->getElementType(); 2697 2698 Value *ResultR, *ResultI; 2699 if (CETy->isRealFloatingType()) { 2700 ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 2701 LHS.first, RHS.first, "cmp.r"); 2702 ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc, 2703 LHS.second, RHS.second, "cmp.i"); 2704 } else { 2705 // Complex comparisons can only be equality comparisons. As such, signed 2706 // and unsigned opcodes are the same. 2707 ResultR = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2708 LHS.first, RHS.first, "cmp.r"); 2709 ResultI = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc, 2710 LHS.second, RHS.second, "cmp.i"); 2711 } 2712 2713 if (E->getOpcode() == BO_EQ) { 2714 Result = Builder.CreateAnd(ResultR, ResultI, "and.ri"); 2715 } else { 2716 assert(E->getOpcode() == BO_NE && 2717 "Complex comparison other than == or != ?"); 2718 Result = Builder.CreateOr(ResultR, ResultI, "or.ri"); 2719 } 2720 } 2721 2722 return EmitScalarConversion(Result, CGF.getContext().BoolTy, E->getType()); 2723 } 2724 2725 Value *ScalarExprEmitter::VisitBinAssign(const BinaryOperator *E) { 2726 bool Ignore = TestAndClearIgnoreResultAssign(); 2727 2728 Value *RHS; 2729 LValue LHS; 2730 2731 switch (E->getLHS()->getType().getObjCLifetime()) { 2732 case Qualifiers::OCL_Strong: 2733 llvm::tie(LHS, RHS) = CGF.EmitARCStoreStrong(E, Ignore); 2734 break; 2735 2736 case Qualifiers::OCL_Autoreleasing: 2737 llvm::tie(LHS,RHS) = CGF.EmitARCStoreAutoreleasing(E); 2738 break; 2739 2740 case Qualifiers::OCL_Weak: 2741 RHS = Visit(E->getRHS()); 2742 LHS = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store); 2743 RHS = CGF.EmitARCStoreWeak(LHS.getAddress(), RHS, Ignore); 2744 break; 2745 2746 // No reason to do any of these differently. 2747 case Qualifiers::OCL_None: 2748 case Qualifiers::OCL_ExplicitNone: 2749 // __block variables need to have the rhs evaluated first, plus 2750 // this should improve codegen just a little. 2751 RHS = Visit(E->getRHS()); 2752 LHS = EmitCheckedLValue(E->getLHS(), CodeGenFunction::TCK_Store); 2753 2754 // Store the value into the LHS. Bit-fields are handled specially 2755 // because the result is altered by the store, i.e., [C99 6.5.16p1] 2756 // 'An assignment expression has the value of the left operand after 2757 // the assignment...'. 2758 if (LHS.isBitField()) 2759 CGF.EmitStoreThroughBitfieldLValue(RValue::get(RHS), LHS, &RHS); 2760 else 2761 CGF.EmitStoreThroughLValue(RValue::get(RHS), LHS); 2762 } 2763 2764 // If the result is clearly ignored, return now. 2765 if (Ignore) 2766 return 0; 2767 2768 // The result of an assignment in C is the assigned r-value. 2769 if (!CGF.getLangOpts().CPlusPlus) 2770 return RHS; 2771 2772 // If the lvalue is non-volatile, return the computed value of the assignment. 2773 if (!LHS.isVolatileQualified()) 2774 return RHS; 2775 2776 // Otherwise, reload the value. 2777 return EmitLoadOfLValue(LHS); 2778 } 2779 2780 Value *ScalarExprEmitter::VisitBinLAnd(const BinaryOperator *E) { 2781 // Perform vector logical and on comparisons with zero vectors. 2782 if (E->getType()->isVectorType()) { 2783 Value *LHS = Visit(E->getLHS()); 2784 Value *RHS = Visit(E->getRHS()); 2785 Value *Zero = llvm::ConstantAggregateZero::get(LHS->getType()); 2786 if (LHS->getType()->isFPOrFPVectorTy()) { 2787 LHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, LHS, Zero, "cmp"); 2788 RHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, RHS, Zero, "cmp"); 2789 } else { 2790 LHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, LHS, Zero, "cmp"); 2791 RHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, RHS, Zero, "cmp"); 2792 } 2793 Value *And = Builder.CreateAnd(LHS, RHS); 2794 return Builder.CreateSExt(And, ConvertType(E->getType()), "sext"); 2795 } 2796 2797 llvm::Type *ResTy = ConvertType(E->getType()); 2798 2799 // If we have 0 && RHS, see if we can elide RHS, if so, just return 0. 2800 // If we have 1 && X, just emit X without inserting the control flow. 2801 bool LHSCondVal; 2802 if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) { 2803 if (LHSCondVal) { // If we have 1 && X, just emit X. 2804 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2805 // ZExt result to int or bool. 2806 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "land.ext"); 2807 } 2808 2809 // 0 && RHS: If it is safe, just elide the RHS, and return 0/false. 2810 if (!CGF.ContainsLabel(E->getRHS())) 2811 return llvm::Constant::getNullValue(ResTy); 2812 } 2813 2814 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("land.end"); 2815 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("land.rhs"); 2816 2817 CodeGenFunction::ConditionalEvaluation eval(CGF); 2818 2819 // Branch on the LHS first. If it is false, go to the failure (cont) block. 2820 CGF.EmitBranchOnBoolExpr(E->getLHS(), RHSBlock, ContBlock); 2821 2822 // Any edges into the ContBlock are now from an (indeterminate number of) 2823 // edges from this first condition. All of these values will be false. Start 2824 // setting up the PHI node in the Cont Block for this. 2825 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2, 2826 "", ContBlock); 2827 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 2828 PI != PE; ++PI) 2829 PN->addIncoming(llvm::ConstantInt::getFalse(VMContext), *PI); 2830 2831 eval.begin(CGF); 2832 CGF.EmitBlock(RHSBlock); 2833 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2834 eval.end(CGF); 2835 2836 // Reaquire the RHS block, as there may be subblocks inserted. 2837 RHSBlock = Builder.GetInsertBlock(); 2838 2839 // Emit an unconditional branch from this block to ContBlock. Insert an entry 2840 // into the phi node for the edge with the value of RHSCond. 2841 if (CGF.getDebugInfo()) 2842 // There is no need to emit line number for unconditional branch. 2843 Builder.SetCurrentDebugLocation(llvm::DebugLoc()); 2844 CGF.EmitBlock(ContBlock); 2845 PN->addIncoming(RHSCond, RHSBlock); 2846 2847 // ZExt result to int. 2848 return Builder.CreateZExtOrBitCast(PN, ResTy, "land.ext"); 2849 } 2850 2851 Value *ScalarExprEmitter::VisitBinLOr(const BinaryOperator *E) { 2852 // Perform vector logical or on comparisons with zero vectors. 2853 if (E->getType()->isVectorType()) { 2854 Value *LHS = Visit(E->getLHS()); 2855 Value *RHS = Visit(E->getRHS()); 2856 Value *Zero = llvm::ConstantAggregateZero::get(LHS->getType()); 2857 if (LHS->getType()->isFPOrFPVectorTy()) { 2858 LHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, LHS, Zero, "cmp"); 2859 RHS = Builder.CreateFCmp(llvm::CmpInst::FCMP_UNE, RHS, Zero, "cmp"); 2860 } else { 2861 LHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, LHS, Zero, "cmp"); 2862 RHS = Builder.CreateICmp(llvm::CmpInst::ICMP_NE, RHS, Zero, "cmp"); 2863 } 2864 Value *Or = Builder.CreateOr(LHS, RHS); 2865 return Builder.CreateSExt(Or, ConvertType(E->getType()), "sext"); 2866 } 2867 2868 llvm::Type *ResTy = ConvertType(E->getType()); 2869 2870 // If we have 1 || RHS, see if we can elide RHS, if so, just return 1. 2871 // If we have 0 || X, just emit X without inserting the control flow. 2872 bool LHSCondVal; 2873 if (CGF.ConstantFoldsToSimpleInteger(E->getLHS(), LHSCondVal)) { 2874 if (!LHSCondVal) { // If we have 0 || X, just emit X. 2875 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2876 // ZExt result to int or bool. 2877 return Builder.CreateZExtOrBitCast(RHSCond, ResTy, "lor.ext"); 2878 } 2879 2880 // 1 || RHS: If it is safe, just elide the RHS, and return 1/true. 2881 if (!CGF.ContainsLabel(E->getRHS())) 2882 return llvm::ConstantInt::get(ResTy, 1); 2883 } 2884 2885 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("lor.end"); 2886 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("lor.rhs"); 2887 2888 CodeGenFunction::ConditionalEvaluation eval(CGF); 2889 2890 // Branch on the LHS first. If it is true, go to the success (cont) block. 2891 CGF.EmitBranchOnBoolExpr(E->getLHS(), ContBlock, RHSBlock); 2892 2893 // Any edges into the ContBlock are now from an (indeterminate number of) 2894 // edges from this first condition. All of these values will be true. Start 2895 // setting up the PHI node in the Cont Block for this. 2896 llvm::PHINode *PN = llvm::PHINode::Create(llvm::Type::getInt1Ty(VMContext), 2, 2897 "", ContBlock); 2898 for (llvm::pred_iterator PI = pred_begin(ContBlock), PE = pred_end(ContBlock); 2899 PI != PE; ++PI) 2900 PN->addIncoming(llvm::ConstantInt::getTrue(VMContext), *PI); 2901 2902 eval.begin(CGF); 2903 2904 // Emit the RHS condition as a bool value. 2905 CGF.EmitBlock(RHSBlock); 2906 Value *RHSCond = CGF.EvaluateExprAsBool(E->getRHS()); 2907 2908 eval.end(CGF); 2909 2910 // Reaquire the RHS block, as there may be subblocks inserted. 2911 RHSBlock = Builder.GetInsertBlock(); 2912 2913 // Emit an unconditional branch from this block to ContBlock. Insert an entry 2914 // into the phi node for the edge with the value of RHSCond. 2915 CGF.EmitBlock(ContBlock); 2916 PN->addIncoming(RHSCond, RHSBlock); 2917 2918 // ZExt result to int. 2919 return Builder.CreateZExtOrBitCast(PN, ResTy, "lor.ext"); 2920 } 2921 2922 Value *ScalarExprEmitter::VisitBinComma(const BinaryOperator *E) { 2923 CGF.EmitIgnoredExpr(E->getLHS()); 2924 CGF.EnsureInsertPoint(); 2925 return Visit(E->getRHS()); 2926 } 2927 2928 //===----------------------------------------------------------------------===// 2929 // Other Operators 2930 //===----------------------------------------------------------------------===// 2931 2932 /// isCheapEnoughToEvaluateUnconditionally - Return true if the specified 2933 /// expression is cheap enough and side-effect-free enough to evaluate 2934 /// unconditionally instead of conditionally. This is used to convert control 2935 /// flow into selects in some cases. 2936 static bool isCheapEnoughToEvaluateUnconditionally(const Expr *E, 2937 CodeGenFunction &CGF) { 2938 E = E->IgnoreParens(); 2939 2940 // Anything that is an integer or floating point constant is fine. 2941 if (E->isConstantInitializer(CGF.getContext(), false)) 2942 return true; 2943 2944 // Non-volatile automatic variables too, to get "cond ? X : Y" where 2945 // X and Y are local variables. 2946 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) 2947 if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) 2948 if (VD->hasLocalStorage() && !(CGF.getContext() 2949 .getCanonicalType(VD->getType()) 2950 .isVolatileQualified())) 2951 return true; 2952 2953 return false; 2954 } 2955 2956 2957 Value *ScalarExprEmitter:: 2958 VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) { 2959 TestAndClearIgnoreResultAssign(); 2960 2961 // Bind the common expression if necessary. 2962 CodeGenFunction::OpaqueValueMapping binding(CGF, E); 2963 2964 Expr *condExpr = E->getCond(); 2965 Expr *lhsExpr = E->getTrueExpr(); 2966 Expr *rhsExpr = E->getFalseExpr(); 2967 2968 // If the condition constant folds and can be elided, try to avoid emitting 2969 // the condition and the dead arm. 2970 bool CondExprBool; 2971 if (CGF.ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) { 2972 Expr *live = lhsExpr, *dead = rhsExpr; 2973 if (!CondExprBool) std::swap(live, dead); 2974 2975 // If the dead side doesn't have labels we need, just emit the Live part. 2976 if (!CGF.ContainsLabel(dead)) { 2977 Value *Result = Visit(live); 2978 2979 // If the live part is a throw expression, it acts like it has a void 2980 // type, so evaluating it returns a null Value*. However, a conditional 2981 // with non-void type must return a non-null Value*. 2982 if (!Result && !E->getType()->isVoidType()) 2983 Result = llvm::UndefValue::get(CGF.ConvertType(E->getType())); 2984 2985 return Result; 2986 } 2987 } 2988 2989 // OpenCL: If the condition is a vector, we can treat this condition like 2990 // the select function. 2991 if (CGF.getLangOpts().OpenCL 2992 && condExpr->getType()->isVectorType()) { 2993 llvm::Value *CondV = CGF.EmitScalarExpr(condExpr); 2994 llvm::Value *LHS = Visit(lhsExpr); 2995 llvm::Value *RHS = Visit(rhsExpr); 2996 2997 llvm::Type *condType = ConvertType(condExpr->getType()); 2998 llvm::VectorType *vecTy = cast<llvm::VectorType>(condType); 2999 3000 unsigned numElem = vecTy->getNumElements(); 3001 llvm::Type *elemType = vecTy->getElementType(); 3002 3003 llvm::Value *zeroVec = llvm::Constant::getNullValue(vecTy); 3004 llvm::Value *TestMSB = Builder.CreateICmpSLT(CondV, zeroVec); 3005 llvm::Value *tmp = Builder.CreateSExt(TestMSB, 3006 llvm::VectorType::get(elemType, 3007 numElem), 3008 "sext"); 3009 llvm::Value *tmp2 = Builder.CreateNot(tmp); 3010 3011 // Cast float to int to perform ANDs if necessary. 3012 llvm::Value *RHSTmp = RHS; 3013 llvm::Value *LHSTmp = LHS; 3014 bool wasCast = false; 3015 llvm::VectorType *rhsVTy = cast<llvm::VectorType>(RHS->getType()); 3016 if (rhsVTy->getElementType()->isFloatingPointTy()) { 3017 RHSTmp = Builder.CreateBitCast(RHS, tmp2->getType()); 3018 LHSTmp = Builder.CreateBitCast(LHS, tmp->getType()); 3019 wasCast = true; 3020 } 3021 3022 llvm::Value *tmp3 = Builder.CreateAnd(RHSTmp, tmp2); 3023 llvm::Value *tmp4 = Builder.CreateAnd(LHSTmp, tmp); 3024 llvm::Value *tmp5 = Builder.CreateOr(tmp3, tmp4, "cond"); 3025 if (wasCast) 3026 tmp5 = Builder.CreateBitCast(tmp5, RHS->getType()); 3027 3028 return tmp5; 3029 } 3030 3031 // If this is a really simple expression (like x ? 4 : 5), emit this as a 3032 // select instead of as control flow. We can only do this if it is cheap and 3033 // safe to evaluate the LHS and RHS unconditionally. 3034 if (isCheapEnoughToEvaluateUnconditionally(lhsExpr, CGF) && 3035 isCheapEnoughToEvaluateUnconditionally(rhsExpr, CGF)) { 3036 llvm::Value *CondV = CGF.EvaluateExprAsBool(condExpr); 3037 llvm::Value *LHS = Visit(lhsExpr); 3038 llvm::Value *RHS = Visit(rhsExpr); 3039 if (!LHS) { 3040 // If the conditional has void type, make sure we return a null Value*. 3041 assert(!RHS && "LHS and RHS types must match"); 3042 return 0; 3043 } 3044 return Builder.CreateSelect(CondV, LHS, RHS, "cond"); 3045 } 3046 3047 llvm::BasicBlock *LHSBlock = CGF.createBasicBlock("cond.true"); 3048 llvm::BasicBlock *RHSBlock = CGF.createBasicBlock("cond.false"); 3049 llvm::BasicBlock *ContBlock = CGF.createBasicBlock("cond.end"); 3050 3051 CodeGenFunction::ConditionalEvaluation eval(CGF); 3052 CGF.EmitBranchOnBoolExpr(condExpr, LHSBlock, RHSBlock); 3053 3054 CGF.EmitBlock(LHSBlock); 3055 eval.begin(CGF); 3056 Value *LHS = Visit(lhsExpr); 3057 eval.end(CGF); 3058 3059 LHSBlock = Builder.GetInsertBlock(); 3060 Builder.CreateBr(ContBlock); 3061 3062 CGF.EmitBlock(RHSBlock); 3063 eval.begin(CGF); 3064 Value *RHS = Visit(rhsExpr); 3065 eval.end(CGF); 3066 3067 RHSBlock = Builder.GetInsertBlock(); 3068 CGF.EmitBlock(ContBlock); 3069 3070 // If the LHS or RHS is a throw expression, it will be legitimately null. 3071 if (!LHS) 3072 return RHS; 3073 if (!RHS) 3074 return LHS; 3075 3076 // Create a PHI node for the real part. 3077 llvm::PHINode *PN = Builder.CreatePHI(LHS->getType(), 2, "cond"); 3078 PN->addIncoming(LHS, LHSBlock); 3079 PN->addIncoming(RHS, RHSBlock); 3080 return PN; 3081 } 3082 3083 Value *ScalarExprEmitter::VisitChooseExpr(ChooseExpr *E) { 3084 return Visit(E->getChosenSubExpr(CGF.getContext())); 3085 } 3086 3087 Value *ScalarExprEmitter::VisitVAArgExpr(VAArgExpr *VE) { 3088 llvm::Value *ArgValue = CGF.EmitVAListRef(VE->getSubExpr()); 3089 llvm::Value *ArgPtr = CGF.EmitVAArg(ArgValue, VE->getType()); 3090 3091 // If EmitVAArg fails, we fall back to the LLVM instruction. 3092 if (!ArgPtr) 3093 return Builder.CreateVAArg(ArgValue, ConvertType(VE->getType())); 3094 3095 // FIXME Volatility. 3096 return Builder.CreateLoad(ArgPtr); 3097 } 3098 3099 Value *ScalarExprEmitter::VisitBlockExpr(const BlockExpr *block) { 3100 return CGF.EmitBlockLiteral(block); 3101 } 3102 3103 Value *ScalarExprEmitter::VisitAsTypeExpr(AsTypeExpr *E) { 3104 Value *Src = CGF.EmitScalarExpr(E->getSrcExpr()); 3105 llvm::Type *DstTy = ConvertType(E->getType()); 3106 3107 // Going from vec4->vec3 or vec3->vec4 is a special case and requires 3108 // a shuffle vector instead of a bitcast. 3109 llvm::Type *SrcTy = Src->getType(); 3110 if (isa<llvm::VectorType>(DstTy) && isa<llvm::VectorType>(SrcTy)) { 3111 unsigned numElementsDst = cast<llvm::VectorType>(DstTy)->getNumElements(); 3112 unsigned numElementsSrc = cast<llvm::VectorType>(SrcTy)->getNumElements(); 3113 if ((numElementsDst == 3 && numElementsSrc == 4) 3114 || (numElementsDst == 4 && numElementsSrc == 3)) { 3115 3116 3117 // In the case of going from int4->float3, a bitcast is needed before 3118 // doing a shuffle. 3119 llvm::Type *srcElemTy = 3120 cast<llvm::VectorType>(SrcTy)->getElementType(); 3121 llvm::Type *dstElemTy = 3122 cast<llvm::VectorType>(DstTy)->getElementType(); 3123 3124 if ((srcElemTy->isIntegerTy() && dstElemTy->isFloatTy()) 3125 || (srcElemTy->isFloatTy() && dstElemTy->isIntegerTy())) { 3126 // Create a float type of the same size as the source or destination. 3127 llvm::VectorType *newSrcTy = llvm::VectorType::get(dstElemTy, 3128 numElementsSrc); 3129 3130 Src = Builder.CreateBitCast(Src, newSrcTy, "astypeCast"); 3131 } 3132 3133 llvm::Value *UnV = llvm::UndefValue::get(Src->getType()); 3134 3135 SmallVector<llvm::Constant*, 3> Args; 3136 Args.push_back(Builder.getInt32(0)); 3137 Args.push_back(Builder.getInt32(1)); 3138 Args.push_back(Builder.getInt32(2)); 3139 3140 if (numElementsDst == 4) 3141 Args.push_back(llvm::UndefValue::get(CGF.Int32Ty)); 3142 3143 llvm::Constant *Mask = llvm::ConstantVector::get(Args); 3144 3145 return Builder.CreateShuffleVector(Src, UnV, Mask, "astype"); 3146 } 3147 } 3148 3149 return Builder.CreateBitCast(Src, DstTy, "astype"); 3150 } 3151 3152 Value *ScalarExprEmitter::VisitAtomicExpr(AtomicExpr *E) { 3153 return CGF.EmitAtomicExpr(E).getScalarVal(); 3154 } 3155 3156 //===----------------------------------------------------------------------===// 3157 // Entry Point into this File 3158 //===----------------------------------------------------------------------===// 3159 3160 /// EmitScalarExpr - Emit the computation of the specified expression of scalar 3161 /// type, ignoring the result. 3162 Value *CodeGenFunction::EmitScalarExpr(const Expr *E, bool IgnoreResultAssign) { 3163 assert(E && hasScalarEvaluationKind(E->getType()) && 3164 "Invalid scalar expression to emit"); 3165 3166 if (isa<CXXDefaultArgExpr>(E)) 3167 disableDebugInfo(); 3168 Value *V = ScalarExprEmitter(*this, IgnoreResultAssign) 3169 .Visit(const_cast<Expr*>(E)); 3170 if (isa<CXXDefaultArgExpr>(E)) 3171 enableDebugInfo(); 3172 return V; 3173 } 3174 3175 /// EmitScalarConversion - Emit a conversion from the specified type to the 3176 /// specified destination type, both of which are LLVM scalar types. 3177 Value *CodeGenFunction::EmitScalarConversion(Value *Src, QualType SrcTy, 3178 QualType DstTy) { 3179 assert(hasScalarEvaluationKind(SrcTy) && hasScalarEvaluationKind(DstTy) && 3180 "Invalid scalar expression to emit"); 3181 return ScalarExprEmitter(*this).EmitScalarConversion(Src, SrcTy, DstTy); 3182 } 3183 3184 /// EmitComplexToScalarConversion - Emit a conversion from the specified complex 3185 /// type to the specified destination type, where the destination type is an 3186 /// LLVM scalar type. 3187 Value *CodeGenFunction::EmitComplexToScalarConversion(ComplexPairTy Src, 3188 QualType SrcTy, 3189 QualType DstTy) { 3190 assert(SrcTy->isAnyComplexType() && hasScalarEvaluationKind(DstTy) && 3191 "Invalid complex -> scalar conversion"); 3192 return ScalarExprEmitter(*this).EmitComplexToScalarConversion(Src, SrcTy, 3193 DstTy); 3194 } 3195 3196 3197 llvm::Value *CodeGenFunction:: 3198 EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV, 3199 bool isInc, bool isPre) { 3200 return ScalarExprEmitter(*this).EmitScalarPrePostIncDec(E, LV, isInc, isPre); 3201 } 3202 3203 LValue CodeGenFunction::EmitObjCIsaExpr(const ObjCIsaExpr *E) { 3204 llvm::Value *V; 3205 // object->isa or (*object).isa 3206 // Generate code as for: *(Class*)object 3207 // build Class* type 3208 llvm::Type *ClassPtrTy = ConvertType(E->getType()); 3209 3210 Expr *BaseExpr = E->getBase(); 3211 if (BaseExpr->isRValue()) { 3212 V = CreateMemTemp(E->getType(), "resval"); 3213 llvm::Value *Src = EmitScalarExpr(BaseExpr); 3214 Builder.CreateStore(Src, V); 3215 V = ScalarExprEmitter(*this).EmitLoadOfLValue( 3216 MakeNaturalAlignAddrLValue(V, E->getType())); 3217 } else { 3218 if (E->isArrow()) 3219 V = ScalarExprEmitter(*this).EmitLoadOfLValue(BaseExpr); 3220 else 3221 V = EmitLValue(BaseExpr).getAddress(); 3222 } 3223 3224 // build Class* type 3225 ClassPtrTy = ClassPtrTy->getPointerTo(); 3226 V = Builder.CreateBitCast(V, ClassPtrTy); 3227 return MakeNaturalAlignAddrLValue(V, E->getType()); 3228 } 3229 3230 3231 LValue CodeGenFunction::EmitCompoundAssignmentLValue( 3232 const CompoundAssignOperator *E) { 3233 ScalarExprEmitter Scalar(*this); 3234 Value *Result = 0; 3235 switch (E->getOpcode()) { 3236 #define COMPOUND_OP(Op) \ 3237 case BO_##Op##Assign: \ 3238 return Scalar.EmitCompoundAssignLValue(E, &ScalarExprEmitter::Emit##Op, \ 3239 Result) 3240 COMPOUND_OP(Mul); 3241 COMPOUND_OP(Div); 3242 COMPOUND_OP(Rem); 3243 COMPOUND_OP(Add); 3244 COMPOUND_OP(Sub); 3245 COMPOUND_OP(Shl); 3246 COMPOUND_OP(Shr); 3247 COMPOUND_OP(And); 3248 COMPOUND_OP(Xor); 3249 COMPOUND_OP(Or); 3250 #undef COMPOUND_OP 3251 3252 case BO_PtrMemD: 3253 case BO_PtrMemI: 3254 case BO_Mul: 3255 case BO_Div: 3256 case BO_Rem: 3257 case BO_Add: 3258 case BO_Sub: 3259 case BO_Shl: 3260 case BO_Shr: 3261 case BO_LT: 3262 case BO_GT: 3263 case BO_LE: 3264 case BO_GE: 3265 case BO_EQ: 3266 case BO_NE: 3267 case BO_And: 3268 case BO_Xor: 3269 case BO_Or: 3270 case BO_LAnd: 3271 case BO_LOr: 3272 case BO_Assign: 3273 case BO_Comma: 3274 llvm_unreachable("Not valid compound assignment operators"); 3275 } 3276 3277 llvm_unreachable("Unhandled compound assignment operator"); 3278 } 3279