1 //===--- CGExpr.cpp - Emit LLVM Code from Expressions ---------------------===// 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 as LLVM code. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "CodeGenFunction.h" 15 #include "CodeGenModule.h" 16 #include "CGCall.h" 17 #include "CGCXXABI.h" 18 #include "CGDebugInfo.h" 19 #include "CGRecordLayout.h" 20 #include "CGObjCRuntime.h" 21 #include "TargetInfo.h" 22 #include "clang/AST/ASTContext.h" 23 #include "clang/AST/DeclObjC.h" 24 #include "clang/Frontend/CodeGenOptions.h" 25 #include "llvm/Intrinsics.h" 26 #include "llvm/LLVMContext.h" 27 #include "llvm/Target/TargetData.h" 28 using namespace clang; 29 using namespace CodeGen; 30 31 //===--------------------------------------------------------------------===// 32 // Miscellaneous Helper Methods 33 //===--------------------------------------------------------------------===// 34 35 llvm::Value *CodeGenFunction::EmitCastToVoidPtr(llvm::Value *value) { 36 unsigned addressSpace = 37 cast<llvm::PointerType>(value->getType())->getAddressSpace(); 38 39 llvm::PointerType *destType = Int8PtrTy; 40 if (addressSpace) 41 destType = llvm::Type::getInt8PtrTy(getLLVMContext(), addressSpace); 42 43 if (value->getType() == destType) return value; 44 return Builder.CreateBitCast(value, destType); 45 } 46 47 /// CreateTempAlloca - This creates a alloca and inserts it into the entry 48 /// block. 49 llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, 50 const Twine &Name) { 51 if (!Builder.isNamePreserving()) 52 return new llvm::AllocaInst(Ty, 0, "", AllocaInsertPt); 53 return new llvm::AllocaInst(Ty, 0, Name, AllocaInsertPt); 54 } 55 56 void CodeGenFunction::InitTempAlloca(llvm::AllocaInst *Var, 57 llvm::Value *Init) { 58 llvm::StoreInst *Store = new llvm::StoreInst(Init, Var); 59 llvm::BasicBlock *Block = AllocaInsertPt->getParent(); 60 Block->getInstList().insertAfter(&*AllocaInsertPt, Store); 61 } 62 63 llvm::AllocaInst *CodeGenFunction::CreateIRTemp(QualType Ty, 64 const Twine &Name) { 65 llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertType(Ty), Name); 66 // FIXME: Should we prefer the preferred type alignment here? 67 CharUnits Align = getContext().getTypeAlignInChars(Ty); 68 Alloc->setAlignment(Align.getQuantity()); 69 return Alloc; 70 } 71 72 llvm::AllocaInst *CodeGenFunction::CreateMemTemp(QualType Ty, 73 const Twine &Name) { 74 llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertTypeForMem(Ty), Name); 75 // FIXME: Should we prefer the preferred type alignment here? 76 CharUnits Align = getContext().getTypeAlignInChars(Ty); 77 Alloc->setAlignment(Align.getQuantity()); 78 return Alloc; 79 } 80 81 /// EvaluateExprAsBool - Perform the usual unary conversions on the specified 82 /// expression and compare the result against zero, returning an Int1Ty value. 83 llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) { 84 if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) { 85 llvm::Value *MemPtr = EmitScalarExpr(E); 86 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT); 87 } 88 89 QualType BoolTy = getContext().BoolTy; 90 if (!E->getType()->isAnyComplexType()) 91 return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy); 92 93 return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(),BoolTy); 94 } 95 96 /// EmitIgnoredExpr - Emit code to compute the specified expression, 97 /// ignoring the result. 98 void CodeGenFunction::EmitIgnoredExpr(const Expr *E) { 99 if (E->isRValue()) 100 return (void) EmitAnyExpr(E, AggValueSlot::ignored(), true); 101 102 // Just emit it as an l-value and drop the result. 103 EmitLValue(E); 104 } 105 106 /// EmitAnyExpr - Emit code to compute the specified expression which 107 /// can have any type. The result is returned as an RValue struct. 108 /// If this is an aggregate expression, AggSlot indicates where the 109 /// result should be returned. 110 RValue CodeGenFunction::EmitAnyExpr(const Expr *E, AggValueSlot AggSlot, 111 bool IgnoreResult) { 112 if (!hasAggregateLLVMType(E->getType())) 113 return RValue::get(EmitScalarExpr(E, IgnoreResult)); 114 else if (E->getType()->isAnyComplexType()) 115 return RValue::getComplex(EmitComplexExpr(E, IgnoreResult, IgnoreResult)); 116 117 EmitAggExpr(E, AggSlot, IgnoreResult); 118 return AggSlot.asRValue(); 119 } 120 121 /// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will 122 /// always be accessible even if no aggregate location is provided. 123 RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) { 124 AggValueSlot AggSlot = AggValueSlot::ignored(); 125 126 if (hasAggregateLLVMType(E->getType()) && 127 !E->getType()->isAnyComplexType()) 128 AggSlot = CreateAggTemp(E->getType(), "agg.tmp"); 129 return EmitAnyExpr(E, AggSlot); 130 } 131 132 /// EmitAnyExprToMem - Evaluate an expression into a given memory 133 /// location. 134 void CodeGenFunction::EmitAnyExprToMem(const Expr *E, 135 llvm::Value *Location, 136 Qualifiers Quals, 137 bool IsInit) { 138 if (E->getType()->isAnyComplexType()) 139 EmitComplexExprIntoAddr(E, Location, Quals.hasVolatile()); 140 else if (hasAggregateLLVMType(E->getType())) 141 EmitAggExpr(E, AggValueSlot::forAddr(Location, Quals, 142 AggValueSlot::IsDestructed_t(IsInit), 143 AggValueSlot::DoesNotNeedGCBarriers, 144 AggValueSlot::IsAliased_t(!IsInit))); 145 else { 146 RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false)); 147 LValue LV = MakeAddrLValue(Location, E->getType()); 148 EmitStoreThroughLValue(RV, LV); 149 } 150 } 151 152 namespace { 153 /// \brief An adjustment to be made to the temporary created when emitting a 154 /// reference binding, which accesses a particular subobject of that temporary. 155 struct SubobjectAdjustment { 156 enum { DerivedToBaseAdjustment, FieldAdjustment } Kind; 157 158 union { 159 struct { 160 const CastExpr *BasePath; 161 const CXXRecordDecl *DerivedClass; 162 } DerivedToBase; 163 164 FieldDecl *Field; 165 }; 166 167 SubobjectAdjustment(const CastExpr *BasePath, 168 const CXXRecordDecl *DerivedClass) 169 : Kind(DerivedToBaseAdjustment) { 170 DerivedToBase.BasePath = BasePath; 171 DerivedToBase.DerivedClass = DerivedClass; 172 } 173 174 SubobjectAdjustment(FieldDecl *Field) 175 : Kind(FieldAdjustment) { 176 this->Field = Field; 177 } 178 }; 179 } 180 181 static llvm::Value * 182 CreateReferenceTemporary(CodeGenFunction &CGF, QualType Type, 183 const NamedDecl *InitializedDecl) { 184 if (const VarDecl *VD = dyn_cast_or_null<VarDecl>(InitializedDecl)) { 185 if (VD->hasGlobalStorage()) { 186 llvm::SmallString<256> Name; 187 llvm::raw_svector_ostream Out(Name); 188 CGF.CGM.getCXXABI().getMangleContext().mangleReferenceTemporary(VD, Out); 189 Out.flush(); 190 191 llvm::Type *RefTempTy = CGF.ConvertTypeForMem(Type); 192 193 // Create the reference temporary. 194 llvm::GlobalValue *RefTemp = 195 new llvm::GlobalVariable(CGF.CGM.getModule(), 196 RefTempTy, /*isConstant=*/false, 197 llvm::GlobalValue::InternalLinkage, 198 llvm::Constant::getNullValue(RefTempTy), 199 Name.str()); 200 return RefTemp; 201 } 202 } 203 204 return CGF.CreateMemTemp(Type, "ref.tmp"); 205 } 206 207 static llvm::Value * 208 EmitExprForReferenceBinding(CodeGenFunction &CGF, const Expr *E, 209 llvm::Value *&ReferenceTemporary, 210 const CXXDestructorDecl *&ReferenceTemporaryDtor, 211 QualType &ObjCARCReferenceLifetimeType, 212 const NamedDecl *InitializedDecl) { 213 // Look through expressions for materialized temporaries (for now). 214 if (const MaterializeTemporaryExpr *M 215 = dyn_cast<MaterializeTemporaryExpr>(E)) { 216 // Objective-C++ ARC: 217 // If we are binding a reference to a temporary that has ownership, we 218 // need to perform retain/release operations on the temporary. 219 if (CGF.getContext().getLangOptions().ObjCAutoRefCount && 220 E->getType()->isObjCLifetimeType() && 221 (E->getType().getObjCLifetime() == Qualifiers::OCL_Strong || 222 E->getType().getObjCLifetime() == Qualifiers::OCL_Weak || 223 E->getType().getObjCLifetime() == Qualifiers::OCL_Autoreleasing)) 224 ObjCARCReferenceLifetimeType = E->getType(); 225 226 E = M->GetTemporaryExpr(); 227 } 228 229 if (const CXXDefaultArgExpr *DAE = dyn_cast<CXXDefaultArgExpr>(E)) 230 E = DAE->getExpr(); 231 232 if (const ExprWithCleanups *EWC = dyn_cast<ExprWithCleanups>(E)) { 233 CGF.enterFullExpression(EWC); 234 CodeGenFunction::RunCleanupsScope Scope(CGF); 235 236 return EmitExprForReferenceBinding(CGF, EWC->getSubExpr(), 237 ReferenceTemporary, 238 ReferenceTemporaryDtor, 239 ObjCARCReferenceLifetimeType, 240 InitializedDecl); 241 } 242 243 RValue RV; 244 if (E->isGLValue()) { 245 // Emit the expression as an lvalue. 246 LValue LV = CGF.EmitLValue(E); 247 248 if (LV.isSimple()) 249 return LV.getAddress(); 250 251 // We have to load the lvalue. 252 RV = CGF.EmitLoadOfLValue(LV); 253 } else { 254 if (!ObjCARCReferenceLifetimeType.isNull()) { 255 ReferenceTemporary = CreateReferenceTemporary(CGF, 256 ObjCARCReferenceLifetimeType, 257 InitializedDecl); 258 259 260 LValue RefTempDst = CGF.MakeAddrLValue(ReferenceTemporary, 261 ObjCARCReferenceLifetimeType); 262 263 CGF.EmitScalarInit(E, dyn_cast_or_null<ValueDecl>(InitializedDecl), 264 RefTempDst, false); 265 266 bool ExtendsLifeOfTemporary = false; 267 if (const VarDecl *Var = dyn_cast_or_null<VarDecl>(InitializedDecl)) { 268 if (Var->extendsLifetimeOfTemporary()) 269 ExtendsLifeOfTemporary = true; 270 } else if (InitializedDecl && isa<FieldDecl>(InitializedDecl)) { 271 ExtendsLifeOfTemporary = true; 272 } 273 274 if (!ExtendsLifeOfTemporary) { 275 // Since the lifetime of this temporary isn't going to be extended, 276 // we need to clean it up ourselves at the end of the full expression. 277 switch (ObjCARCReferenceLifetimeType.getObjCLifetime()) { 278 case Qualifiers::OCL_None: 279 case Qualifiers::OCL_ExplicitNone: 280 case Qualifiers::OCL_Autoreleasing: 281 break; 282 283 case Qualifiers::OCL_Strong: { 284 assert(!ObjCARCReferenceLifetimeType->isArrayType()); 285 CleanupKind cleanupKind = CGF.getARCCleanupKind(); 286 CGF.pushDestroy(cleanupKind, 287 ReferenceTemporary, 288 ObjCARCReferenceLifetimeType, 289 CodeGenFunction::destroyARCStrongImprecise, 290 cleanupKind & EHCleanup); 291 break; 292 } 293 294 case Qualifiers::OCL_Weak: 295 assert(!ObjCARCReferenceLifetimeType->isArrayType()); 296 CGF.pushDestroy(NormalAndEHCleanup, 297 ReferenceTemporary, 298 ObjCARCReferenceLifetimeType, 299 CodeGenFunction::destroyARCWeak, 300 /*useEHCleanupForArray*/ true); 301 break; 302 } 303 304 ObjCARCReferenceLifetimeType = QualType(); 305 } 306 307 return ReferenceTemporary; 308 } 309 310 SmallVector<SubobjectAdjustment, 2> Adjustments; 311 while (true) { 312 E = E->IgnoreParens(); 313 314 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) { 315 if ((CE->getCastKind() == CK_DerivedToBase || 316 CE->getCastKind() == CK_UncheckedDerivedToBase) && 317 E->getType()->isRecordType()) { 318 E = CE->getSubExpr(); 319 CXXRecordDecl *Derived 320 = cast<CXXRecordDecl>(E->getType()->getAs<RecordType>()->getDecl()); 321 Adjustments.push_back(SubobjectAdjustment(CE, Derived)); 322 continue; 323 } 324 325 if (CE->getCastKind() == CK_NoOp) { 326 E = CE->getSubExpr(); 327 continue; 328 } 329 } else if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) { 330 if (!ME->isArrow() && ME->getBase()->isRValue()) { 331 assert(ME->getBase()->getType()->isRecordType()); 332 if (FieldDecl *Field = dyn_cast<FieldDecl>(ME->getMemberDecl())) { 333 E = ME->getBase(); 334 Adjustments.push_back(SubobjectAdjustment(Field)); 335 continue; 336 } 337 } 338 } 339 340 if (const OpaqueValueExpr *opaque = dyn_cast<OpaqueValueExpr>(E)) 341 if (opaque->getType()->isRecordType()) 342 return CGF.EmitOpaqueValueLValue(opaque).getAddress(); 343 344 // Nothing changed. 345 break; 346 } 347 348 // Create a reference temporary if necessary. 349 AggValueSlot AggSlot = AggValueSlot::ignored(); 350 if (CGF.hasAggregateLLVMType(E->getType()) && 351 !E->getType()->isAnyComplexType()) { 352 ReferenceTemporary = CreateReferenceTemporary(CGF, E->getType(), 353 InitializedDecl); 354 AggValueSlot::IsDestructed_t isDestructed 355 = AggValueSlot::IsDestructed_t(InitializedDecl != 0); 356 AggSlot = AggValueSlot::forAddr(ReferenceTemporary, Qualifiers(), 357 isDestructed, 358 AggValueSlot::DoesNotNeedGCBarriers, 359 AggValueSlot::IsNotAliased); 360 } 361 362 if (InitializedDecl) { 363 // Get the destructor for the reference temporary. 364 if (const RecordType *RT = E->getType()->getAs<RecordType>()) { 365 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RT->getDecl()); 366 if (!ClassDecl->hasTrivialDestructor()) 367 ReferenceTemporaryDtor = ClassDecl->getDestructor(); 368 } 369 } 370 371 RV = CGF.EmitAnyExpr(E, AggSlot); 372 373 // Check if need to perform derived-to-base casts and/or field accesses, to 374 // get from the temporary object we created (and, potentially, for which we 375 // extended the lifetime) to the subobject we're binding the reference to. 376 if (!Adjustments.empty()) { 377 llvm::Value *Object = RV.getAggregateAddr(); 378 for (unsigned I = Adjustments.size(); I != 0; --I) { 379 SubobjectAdjustment &Adjustment = Adjustments[I-1]; 380 switch (Adjustment.Kind) { 381 case SubobjectAdjustment::DerivedToBaseAdjustment: 382 Object = 383 CGF.GetAddressOfBaseClass(Object, 384 Adjustment.DerivedToBase.DerivedClass, 385 Adjustment.DerivedToBase.BasePath->path_begin(), 386 Adjustment.DerivedToBase.BasePath->path_end(), 387 /*NullCheckValue=*/false); 388 break; 389 390 case SubobjectAdjustment::FieldAdjustment: { 391 LValue LV = 392 CGF.EmitLValueForField(Object, Adjustment.Field, 0); 393 if (LV.isSimple()) { 394 Object = LV.getAddress(); 395 break; 396 } 397 398 // For non-simple lvalues, we actually have to create a copy of 399 // the object we're binding to. 400 QualType T = Adjustment.Field->getType().getNonReferenceType() 401 .getUnqualifiedType(); 402 Object = CreateReferenceTemporary(CGF, T, InitializedDecl); 403 LValue TempLV = CGF.MakeAddrLValue(Object, 404 Adjustment.Field->getType()); 405 CGF.EmitStoreThroughLValue(CGF.EmitLoadOfLValue(LV), TempLV); 406 break; 407 } 408 409 } 410 } 411 412 return Object; 413 } 414 } 415 416 if (RV.isAggregate()) 417 return RV.getAggregateAddr(); 418 419 // Create a temporary variable that we can bind the reference to. 420 ReferenceTemporary = CreateReferenceTemporary(CGF, E->getType(), 421 InitializedDecl); 422 423 424 unsigned Alignment = 425 CGF.getContext().getTypeAlignInChars(E->getType()).getQuantity(); 426 if (RV.isScalar()) 427 CGF.EmitStoreOfScalar(RV.getScalarVal(), ReferenceTemporary, 428 /*Volatile=*/false, Alignment, E->getType()); 429 else 430 CGF.StoreComplexToAddr(RV.getComplexVal(), ReferenceTemporary, 431 /*Volatile=*/false); 432 return ReferenceTemporary; 433 } 434 435 RValue 436 CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E, 437 const NamedDecl *InitializedDecl) { 438 llvm::Value *ReferenceTemporary = 0; 439 const CXXDestructorDecl *ReferenceTemporaryDtor = 0; 440 QualType ObjCARCReferenceLifetimeType; 441 llvm::Value *Value = EmitExprForReferenceBinding(*this, E, ReferenceTemporary, 442 ReferenceTemporaryDtor, 443 ObjCARCReferenceLifetimeType, 444 InitializedDecl); 445 if (!ReferenceTemporaryDtor && ObjCARCReferenceLifetimeType.isNull()) 446 return RValue::get(Value); 447 448 // Make sure to call the destructor for the reference temporary. 449 const VarDecl *VD = dyn_cast_or_null<VarDecl>(InitializedDecl); 450 if (VD && VD->hasGlobalStorage()) { 451 if (ReferenceTemporaryDtor) { 452 llvm::Constant *DtorFn = 453 CGM.GetAddrOfCXXDestructor(ReferenceTemporaryDtor, Dtor_Complete); 454 EmitCXXGlobalDtorRegistration(DtorFn, 455 cast<llvm::Constant>(ReferenceTemporary)); 456 } else { 457 assert(!ObjCARCReferenceLifetimeType.isNull()); 458 // Note: We intentionally do not register a global "destructor" to 459 // release the object. 460 } 461 462 return RValue::get(Value); 463 } 464 465 if (ReferenceTemporaryDtor) 466 PushDestructorCleanup(ReferenceTemporaryDtor, ReferenceTemporary); 467 else { 468 switch (ObjCARCReferenceLifetimeType.getObjCLifetime()) { 469 case Qualifiers::OCL_None: 470 llvm_unreachable( 471 "Not a reference temporary that needs to be deallocated"); 472 case Qualifiers::OCL_ExplicitNone: 473 case Qualifiers::OCL_Autoreleasing: 474 // Nothing to do. 475 break; 476 477 case Qualifiers::OCL_Strong: { 478 bool precise = VD && VD->hasAttr<ObjCPreciseLifetimeAttr>(); 479 CleanupKind cleanupKind = getARCCleanupKind(); 480 // This local is a GCC and MSVC compiler workaround. 481 Destroyer *destroyer = precise ? &destroyARCStrongPrecise : 482 &destroyARCStrongImprecise; 483 pushDestroy(cleanupKind, ReferenceTemporary, ObjCARCReferenceLifetimeType, 484 *destroyer, cleanupKind & EHCleanup); 485 break; 486 } 487 488 case Qualifiers::OCL_Weak: { 489 // This local is a GCC and MSVC compiler workaround. 490 Destroyer *destroyer = &destroyARCWeak; 491 // __weak objects always get EH cleanups; otherwise, exceptions 492 // could cause really nasty crashes instead of mere leaks. 493 pushDestroy(NormalAndEHCleanup, ReferenceTemporary, 494 ObjCARCReferenceLifetimeType, *destroyer, true); 495 break; 496 } 497 } 498 } 499 500 return RValue::get(Value); 501 } 502 503 504 /// getAccessedFieldNo - Given an encoded value and a result number, return the 505 /// input field number being accessed. 506 unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx, 507 const llvm::Constant *Elts) { 508 if (isa<llvm::ConstantAggregateZero>(Elts)) 509 return 0; 510 511 return cast<llvm::ConstantInt>(Elts->getOperand(Idx))->getZExtValue(); 512 } 513 514 void CodeGenFunction::EmitCheck(llvm::Value *Address, unsigned Size) { 515 if (!CatchUndefined) 516 return; 517 518 // This needs to be to the standard address space. 519 Address = Builder.CreateBitCast(Address, Int8PtrTy); 520 521 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, IntPtrTy); 522 523 // In time, people may want to control this and use a 1 here. 524 llvm::Value *Arg = Builder.getFalse(); 525 llvm::Value *C = Builder.CreateCall2(F, Address, Arg); 526 llvm::BasicBlock *Cont = createBasicBlock(); 527 llvm::BasicBlock *Check = createBasicBlock(); 528 llvm::Value *NegativeOne = llvm::ConstantInt::get(IntPtrTy, -1ULL); 529 Builder.CreateCondBr(Builder.CreateICmpEQ(C, NegativeOne), Cont, Check); 530 531 EmitBlock(Check); 532 Builder.CreateCondBr(Builder.CreateICmpUGE(C, 533 llvm::ConstantInt::get(IntPtrTy, Size)), 534 Cont, getTrapBB()); 535 EmitBlock(Cont); 536 } 537 538 539 CodeGenFunction::ComplexPairTy CodeGenFunction:: 540 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV, 541 bool isInc, bool isPre) { 542 ComplexPairTy InVal = LoadComplexFromAddr(LV.getAddress(), 543 LV.isVolatileQualified()); 544 545 llvm::Value *NextVal; 546 if (isa<llvm::IntegerType>(InVal.first->getType())) { 547 uint64_t AmountVal = isInc ? 1 : -1; 548 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true); 549 550 // Add the inc/dec to the real part. 551 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec"); 552 } else { 553 QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType(); 554 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1); 555 if (!isInc) 556 FVal.changeSign(); 557 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal); 558 559 // Add the inc/dec to the real part. 560 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec"); 561 } 562 563 ComplexPairTy IncVal(NextVal, InVal.second); 564 565 // Store the updated result through the lvalue. 566 StoreComplexToAddr(IncVal, LV.getAddress(), LV.isVolatileQualified()); 567 568 // If this is a postinc, return the value read from memory, otherwise use the 569 // updated value. 570 return isPre ? IncVal : InVal; 571 } 572 573 574 //===----------------------------------------------------------------------===// 575 // LValue Expression Emission 576 //===----------------------------------------------------------------------===// 577 578 RValue CodeGenFunction::GetUndefRValue(QualType Ty) { 579 if (Ty->isVoidType()) 580 return RValue::get(0); 581 582 if (const ComplexType *CTy = Ty->getAs<ComplexType>()) { 583 llvm::Type *EltTy = ConvertType(CTy->getElementType()); 584 llvm::Value *U = llvm::UndefValue::get(EltTy); 585 return RValue::getComplex(std::make_pair(U, U)); 586 } 587 588 // If this is a use of an undefined aggregate type, the aggregate must have an 589 // identifiable address. Just because the contents of the value are undefined 590 // doesn't mean that the address can't be taken and compared. 591 if (hasAggregateLLVMType(Ty)) { 592 llvm::Value *DestPtr = CreateMemTemp(Ty, "undef.agg.tmp"); 593 return RValue::getAggregate(DestPtr); 594 } 595 596 return RValue::get(llvm::UndefValue::get(ConvertType(Ty))); 597 } 598 599 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E, 600 const char *Name) { 601 ErrorUnsupported(E, Name); 602 return GetUndefRValue(E->getType()); 603 } 604 605 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E, 606 const char *Name) { 607 ErrorUnsupported(E, Name); 608 llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType())); 609 return MakeAddrLValue(llvm::UndefValue::get(Ty), E->getType()); 610 } 611 612 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E) { 613 LValue LV = EmitLValue(E); 614 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) 615 EmitCheck(LV.getAddress(), 616 getContext().getTypeSizeInChars(E->getType()).getQuantity()); 617 return LV; 618 } 619 620 /// EmitLValue - Emit code to compute a designator that specifies the location 621 /// of the expression. 622 /// 623 /// This can return one of two things: a simple address or a bitfield reference. 624 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be 625 /// an LLVM pointer type. 626 /// 627 /// If this returns a bitfield reference, nothing about the pointee type of the 628 /// LLVM value is known: For example, it may not be a pointer to an integer. 629 /// 630 /// If this returns a normal address, and if the lvalue's C type is fixed size, 631 /// this method guarantees that the returned pointer type will point to an LLVM 632 /// type of the same size of the lvalue's type. If the lvalue has a variable 633 /// length type, this is not possible. 634 /// 635 LValue CodeGenFunction::EmitLValue(const Expr *E) { 636 switch (E->getStmtClass()) { 637 default: return EmitUnsupportedLValue(E, "l-value expression"); 638 639 case Expr::ObjCPropertyRefExprClass: 640 llvm_unreachable("cannot emit a property reference directly"); 641 642 case Expr::ObjCSelectorExprClass: 643 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E)); 644 case Expr::ObjCIsaExprClass: 645 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E)); 646 case Expr::BinaryOperatorClass: 647 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E)); 648 case Expr::CompoundAssignOperatorClass: 649 if (!E->getType()->isAnyComplexType()) 650 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E)); 651 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E)); 652 case Expr::CallExprClass: 653 case Expr::CXXMemberCallExprClass: 654 case Expr::CXXOperatorCallExprClass: 655 return EmitCallExprLValue(cast<CallExpr>(E)); 656 case Expr::VAArgExprClass: 657 return EmitVAArgExprLValue(cast<VAArgExpr>(E)); 658 case Expr::DeclRefExprClass: 659 return EmitDeclRefLValue(cast<DeclRefExpr>(E)); 660 case Expr::ParenExprClass: 661 return EmitLValue(cast<ParenExpr>(E)->getSubExpr()); 662 case Expr::GenericSelectionExprClass: 663 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr()); 664 case Expr::PredefinedExprClass: 665 return EmitPredefinedLValue(cast<PredefinedExpr>(E)); 666 case Expr::StringLiteralClass: 667 return EmitStringLiteralLValue(cast<StringLiteral>(E)); 668 case Expr::ObjCEncodeExprClass: 669 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E)); 670 case Expr::PseudoObjectExprClass: 671 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E)); 672 673 case Expr::BlockDeclRefExprClass: 674 return EmitBlockDeclRefLValue(cast<BlockDeclRefExpr>(E)); 675 676 case Expr::CXXTemporaryObjectExprClass: 677 case Expr::CXXConstructExprClass: 678 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E)); 679 case Expr::CXXBindTemporaryExprClass: 680 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E)); 681 682 case Expr::ExprWithCleanupsClass: { 683 const ExprWithCleanups *cleanups = cast<ExprWithCleanups>(E); 684 enterFullExpression(cleanups); 685 RunCleanupsScope Scope(*this); 686 return EmitLValue(cleanups->getSubExpr()); 687 } 688 689 case Expr::CXXScalarValueInitExprClass: 690 return EmitNullInitializationLValue(cast<CXXScalarValueInitExpr>(E)); 691 case Expr::CXXDefaultArgExprClass: 692 return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr()); 693 case Expr::CXXTypeidExprClass: 694 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E)); 695 696 case Expr::ObjCMessageExprClass: 697 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E)); 698 case Expr::ObjCIvarRefExprClass: 699 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E)); 700 case Expr::StmtExprClass: 701 return EmitStmtExprLValue(cast<StmtExpr>(E)); 702 case Expr::UnaryOperatorClass: 703 return EmitUnaryOpLValue(cast<UnaryOperator>(E)); 704 case Expr::ArraySubscriptExprClass: 705 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E)); 706 case Expr::ExtVectorElementExprClass: 707 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E)); 708 case Expr::MemberExprClass: 709 return EmitMemberExpr(cast<MemberExpr>(E)); 710 case Expr::CompoundLiteralExprClass: 711 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E)); 712 case Expr::ConditionalOperatorClass: 713 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E)); 714 case Expr::BinaryConditionalOperatorClass: 715 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E)); 716 case Expr::ChooseExprClass: 717 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(getContext())); 718 case Expr::OpaqueValueExprClass: 719 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E)); 720 case Expr::SubstNonTypeTemplateParmExprClass: 721 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement()); 722 case Expr::ImplicitCastExprClass: 723 case Expr::CStyleCastExprClass: 724 case Expr::CXXFunctionalCastExprClass: 725 case Expr::CXXStaticCastExprClass: 726 case Expr::CXXDynamicCastExprClass: 727 case Expr::CXXReinterpretCastExprClass: 728 case Expr::CXXConstCastExprClass: 729 case Expr::ObjCBridgedCastExprClass: 730 return EmitCastLValue(cast<CastExpr>(E)); 731 732 case Expr::MaterializeTemporaryExprClass: 733 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E)); 734 } 735 } 736 737 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue) { 738 return EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatile(), 739 lvalue.getAlignment(), lvalue.getType(), 740 lvalue.getTBAAInfo()); 741 } 742 743 llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile, 744 unsigned Alignment, QualType Ty, 745 llvm::MDNode *TBAAInfo) { 746 llvm::LoadInst *Load = Builder.CreateLoad(Addr); 747 if (Volatile) 748 Load->setVolatile(true); 749 if (Alignment) 750 Load->setAlignment(Alignment); 751 if (TBAAInfo) 752 CGM.DecorateInstruction(Load, TBAAInfo); 753 754 return EmitFromMemory(Load, Ty); 755 } 756 757 static bool isBooleanUnderlyingType(QualType Ty) { 758 if (const EnumType *ET = dyn_cast<EnumType>(Ty)) 759 return ET->getDecl()->getIntegerType()->isBooleanType(); 760 return false; 761 } 762 763 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) { 764 // Bool has a different representation in memory than in registers. 765 if (Ty->isBooleanType() || isBooleanUnderlyingType(Ty)) { 766 // This should really always be an i1, but sometimes it's already 767 // an i8, and it's awkward to track those cases down. 768 if (Value->getType()->isIntegerTy(1)) 769 return Builder.CreateZExt(Value, Builder.getInt8Ty(), "frombool"); 770 assert(Value->getType()->isIntegerTy(8) && "value rep of bool not i1/i8"); 771 } 772 773 return Value; 774 } 775 776 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) { 777 // Bool has a different representation in memory than in registers. 778 if (Ty->isBooleanType() || isBooleanUnderlyingType(Ty)) { 779 assert(Value->getType()->isIntegerTy(8) && "memory rep of bool not i8"); 780 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool"); 781 } 782 783 return Value; 784 } 785 786 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr, 787 bool Volatile, unsigned Alignment, 788 QualType Ty, 789 llvm::MDNode *TBAAInfo) { 790 Value = EmitToMemory(Value, Ty); 791 792 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile); 793 if (Alignment) 794 Store->setAlignment(Alignment); 795 if (TBAAInfo) 796 CGM.DecorateInstruction(Store, TBAAInfo); 797 } 798 799 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue) { 800 EmitStoreOfScalar(value, lvalue.getAddress(), lvalue.isVolatile(), 801 lvalue.getAlignment(), lvalue.getType(), 802 lvalue.getTBAAInfo()); 803 } 804 805 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this 806 /// method emits the address of the lvalue, then loads the result as an rvalue, 807 /// returning the rvalue. 808 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV) { 809 if (LV.isObjCWeak()) { 810 // load of a __weak object. 811 llvm::Value *AddrWeakObj = LV.getAddress(); 812 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this, 813 AddrWeakObj)); 814 } 815 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) 816 return RValue::get(EmitARCLoadWeak(LV.getAddress())); 817 818 if (LV.isSimple()) { 819 assert(!LV.getType()->isFunctionType()); 820 821 // Everything needs a load. 822 return RValue::get(EmitLoadOfScalar(LV)); 823 } 824 825 if (LV.isVectorElt()) { 826 llvm::Value *Vec = Builder.CreateLoad(LV.getVectorAddr(), 827 LV.isVolatileQualified()); 828 return RValue::get(Builder.CreateExtractElement(Vec, LV.getVectorIdx(), 829 "vecext")); 830 } 831 832 // If this is a reference to a subset of the elements of a vector, either 833 // shuffle the input or extract/insert them as appropriate. 834 if (LV.isExtVectorElt()) 835 return EmitLoadOfExtVectorElementLValue(LV); 836 837 assert(LV.isBitField() && "Unknown LValue type!"); 838 return EmitLoadOfBitfieldLValue(LV); 839 } 840 841 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV) { 842 const CGBitFieldInfo &Info = LV.getBitFieldInfo(); 843 844 // Get the output type. 845 llvm::Type *ResLTy = ConvertType(LV.getType()); 846 unsigned ResSizeInBits = CGM.getTargetData().getTypeSizeInBits(ResLTy); 847 848 // Compute the result as an OR of all of the individual component accesses. 849 llvm::Value *Res = 0; 850 for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) { 851 const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i); 852 853 // Get the field pointer. 854 llvm::Value *Ptr = LV.getBitFieldBaseAddr(); 855 856 // Only offset by the field index if used, so that incoming values are not 857 // required to be structures. 858 if (AI.FieldIndex) 859 Ptr = Builder.CreateStructGEP(Ptr, AI.FieldIndex, "bf.field"); 860 861 // Offset by the byte offset, if used. 862 if (!AI.FieldByteOffset.isZero()) { 863 Ptr = EmitCastToVoidPtr(Ptr); 864 Ptr = Builder.CreateConstGEP1_32(Ptr, AI.FieldByteOffset.getQuantity(), 865 "bf.field.offs"); 866 } 867 868 // Cast to the access type. 869 llvm::Type *PTy = llvm::Type::getIntNPtrTy(getLLVMContext(), 870 AI.AccessWidth, 871 CGM.getContext().getTargetAddressSpace(LV.getType())); 872 Ptr = Builder.CreateBitCast(Ptr, PTy); 873 874 // Perform the load. 875 llvm::LoadInst *Load = Builder.CreateLoad(Ptr, LV.isVolatileQualified()); 876 if (!AI.AccessAlignment.isZero()) 877 Load->setAlignment(AI.AccessAlignment.getQuantity()); 878 879 // Shift out unused low bits and mask out unused high bits. 880 llvm::Value *Val = Load; 881 if (AI.FieldBitStart) 882 Val = Builder.CreateLShr(Load, AI.FieldBitStart); 883 Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(AI.AccessWidth, 884 AI.TargetBitWidth), 885 "bf.clear"); 886 887 // Extend or truncate to the target size. 888 if (AI.AccessWidth < ResSizeInBits) 889 Val = Builder.CreateZExt(Val, ResLTy); 890 else if (AI.AccessWidth > ResSizeInBits) 891 Val = Builder.CreateTrunc(Val, ResLTy); 892 893 // Shift into place, and OR into the result. 894 if (AI.TargetBitOffset) 895 Val = Builder.CreateShl(Val, AI.TargetBitOffset); 896 Res = Res ? Builder.CreateOr(Res, Val) : Val; 897 } 898 899 // If the bit-field is signed, perform the sign-extension. 900 // 901 // FIXME: This can easily be folded into the load of the high bits, which 902 // could also eliminate the mask of high bits in some situations. 903 if (Info.isSigned()) { 904 unsigned ExtraBits = ResSizeInBits - Info.getSize(); 905 if (ExtraBits) 906 Res = Builder.CreateAShr(Builder.CreateShl(Res, ExtraBits), 907 ExtraBits, "bf.val.sext"); 908 } 909 910 return RValue::get(Res); 911 } 912 913 // If this is a reference to a subset of the elements of a vector, create an 914 // appropriate shufflevector. 915 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) { 916 llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddr(), 917 LV.isVolatileQualified()); 918 919 const llvm::Constant *Elts = LV.getExtVectorElts(); 920 921 // If the result of the expression is a non-vector type, we must be extracting 922 // a single element. Just codegen as an extractelement. 923 const VectorType *ExprVT = LV.getType()->getAs<VectorType>(); 924 if (!ExprVT) { 925 unsigned InIdx = getAccessedFieldNo(0, Elts); 926 llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx); 927 return RValue::get(Builder.CreateExtractElement(Vec, Elt)); 928 } 929 930 // Always use shuffle vector to try to retain the original program structure 931 unsigned NumResultElts = ExprVT->getNumElements(); 932 933 SmallVector<llvm::Constant*, 4> Mask; 934 for (unsigned i = 0; i != NumResultElts; ++i) { 935 unsigned InIdx = getAccessedFieldNo(i, Elts); 936 Mask.push_back(llvm::ConstantInt::get(Int32Ty, InIdx)); 937 } 938 939 llvm::Value *MaskV = llvm::ConstantVector::get(Mask); 940 Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()), 941 MaskV); 942 return RValue::get(Vec); 943 } 944 945 946 947 /// EmitStoreThroughLValue - Store the specified rvalue into the specified 948 /// lvalue, where both are guaranteed to the have the same type, and that type 949 /// is 'Ty'. 950 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst) { 951 if (!Dst.isSimple()) { 952 if (Dst.isVectorElt()) { 953 // Read/modify/write the vector, inserting the new element. 954 llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddr(), 955 Dst.isVolatileQualified()); 956 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(), 957 Dst.getVectorIdx(), "vecins"); 958 Builder.CreateStore(Vec, Dst.getVectorAddr(),Dst.isVolatileQualified()); 959 return; 960 } 961 962 // If this is an update of extended vector elements, insert them as 963 // appropriate. 964 if (Dst.isExtVectorElt()) 965 return EmitStoreThroughExtVectorComponentLValue(Src, Dst); 966 967 assert(Dst.isBitField() && "Unknown LValue type"); 968 return EmitStoreThroughBitfieldLValue(Src, Dst); 969 } 970 971 // There's special magic for assigning into an ARC-qualified l-value. 972 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) { 973 switch (Lifetime) { 974 case Qualifiers::OCL_None: 975 llvm_unreachable("present but none"); 976 977 case Qualifiers::OCL_ExplicitNone: 978 // nothing special 979 break; 980 981 case Qualifiers::OCL_Strong: 982 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true); 983 return; 984 985 case Qualifiers::OCL_Weak: 986 EmitARCStoreWeak(Dst.getAddress(), Src.getScalarVal(), /*ignore*/ true); 987 return; 988 989 case Qualifiers::OCL_Autoreleasing: 990 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(), 991 Src.getScalarVal())); 992 // fall into the normal path 993 break; 994 } 995 } 996 997 if (Dst.isObjCWeak() && !Dst.isNonGC()) { 998 // load of a __weak object. 999 llvm::Value *LvalueDst = Dst.getAddress(); 1000 llvm::Value *src = Src.getScalarVal(); 1001 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst); 1002 return; 1003 } 1004 1005 if (Dst.isObjCStrong() && !Dst.isNonGC()) { 1006 // load of a __strong object. 1007 llvm::Value *LvalueDst = Dst.getAddress(); 1008 llvm::Value *src = Src.getScalarVal(); 1009 if (Dst.isObjCIvar()) { 1010 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL"); 1011 llvm::Type *ResultType = ConvertType(getContext().LongTy); 1012 llvm::Value *RHS = EmitScalarExpr(Dst.getBaseIvarExp()); 1013 llvm::Value *dst = RHS; 1014 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 1015 llvm::Value *LHS = 1016 Builder.CreatePtrToInt(LvalueDst, ResultType, "sub.ptr.lhs.cast"); 1017 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset"); 1018 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst, 1019 BytesBetween); 1020 } else if (Dst.isGlobalObjCRef()) { 1021 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst, 1022 Dst.isThreadLocalRef()); 1023 } 1024 else 1025 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst); 1026 return; 1027 } 1028 1029 assert(Src.isScalar() && "Can't emit an agg store with this method"); 1030 EmitStoreOfScalar(Src.getScalarVal(), Dst); 1031 } 1032 1033 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst, 1034 llvm::Value **Result) { 1035 const CGBitFieldInfo &Info = Dst.getBitFieldInfo(); 1036 1037 // Get the output type. 1038 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType()); 1039 unsigned ResSizeInBits = CGM.getTargetData().getTypeSizeInBits(ResLTy); 1040 1041 // Get the source value, truncated to the width of the bit-field. 1042 llvm::Value *SrcVal = Src.getScalarVal(); 1043 1044 if (Dst.getType()->isBooleanType()) 1045 SrcVal = Builder.CreateIntCast(SrcVal, ResLTy, /*IsSigned=*/false); 1046 1047 SrcVal = Builder.CreateAnd(SrcVal, llvm::APInt::getLowBitsSet(ResSizeInBits, 1048 Info.getSize()), 1049 "bf.value"); 1050 1051 // Return the new value of the bit-field, if requested. 1052 if (Result) { 1053 // Cast back to the proper type for result. 1054 llvm::Type *SrcTy = Src.getScalarVal()->getType(); 1055 llvm::Value *ReloadVal = Builder.CreateIntCast(SrcVal, SrcTy, false, 1056 "bf.reload.val"); 1057 1058 // Sign extend if necessary. 1059 if (Info.isSigned()) { 1060 unsigned ExtraBits = ResSizeInBits - Info.getSize(); 1061 if (ExtraBits) 1062 ReloadVal = Builder.CreateAShr(Builder.CreateShl(ReloadVal, ExtraBits), 1063 ExtraBits, "bf.reload.sext"); 1064 } 1065 1066 *Result = ReloadVal; 1067 } 1068 1069 // Iterate over the components, writing each piece to memory. 1070 for (unsigned i = 0, e = Info.getNumComponents(); i != e; ++i) { 1071 const CGBitFieldInfo::AccessInfo &AI = Info.getComponent(i); 1072 1073 // Get the field pointer. 1074 llvm::Value *Ptr = Dst.getBitFieldBaseAddr(); 1075 unsigned addressSpace = 1076 cast<llvm::PointerType>(Ptr->getType())->getAddressSpace(); 1077 1078 // Only offset by the field index if used, so that incoming values are not 1079 // required to be structures. 1080 if (AI.FieldIndex) 1081 Ptr = Builder.CreateStructGEP(Ptr, AI.FieldIndex, "bf.field"); 1082 1083 // Offset by the byte offset, if used. 1084 if (!AI.FieldByteOffset.isZero()) { 1085 Ptr = EmitCastToVoidPtr(Ptr); 1086 Ptr = Builder.CreateConstGEP1_32(Ptr, AI.FieldByteOffset.getQuantity(), 1087 "bf.field.offs"); 1088 } 1089 1090 // Cast to the access type. 1091 llvm::Type *AccessLTy = 1092 llvm::Type::getIntNTy(getLLVMContext(), AI.AccessWidth); 1093 1094 llvm::Type *PTy = AccessLTy->getPointerTo(addressSpace); 1095 Ptr = Builder.CreateBitCast(Ptr, PTy); 1096 1097 // Extract the piece of the bit-field value to write in this access, limited 1098 // to the values that are part of this access. 1099 llvm::Value *Val = SrcVal; 1100 if (AI.TargetBitOffset) 1101 Val = Builder.CreateLShr(Val, AI.TargetBitOffset); 1102 Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(ResSizeInBits, 1103 AI.TargetBitWidth)); 1104 1105 // Extend or truncate to the access size. 1106 if (ResSizeInBits < AI.AccessWidth) 1107 Val = Builder.CreateZExt(Val, AccessLTy); 1108 else if (ResSizeInBits > AI.AccessWidth) 1109 Val = Builder.CreateTrunc(Val, AccessLTy); 1110 1111 // Shift into the position in memory. 1112 if (AI.FieldBitStart) 1113 Val = Builder.CreateShl(Val, AI.FieldBitStart); 1114 1115 // If necessary, load and OR in bits that are outside of the bit-field. 1116 if (AI.TargetBitWidth != AI.AccessWidth) { 1117 llvm::LoadInst *Load = Builder.CreateLoad(Ptr, Dst.isVolatileQualified()); 1118 if (!AI.AccessAlignment.isZero()) 1119 Load->setAlignment(AI.AccessAlignment.getQuantity()); 1120 1121 // Compute the mask for zeroing the bits that are part of the bit-field. 1122 llvm::APInt InvMask = 1123 ~llvm::APInt::getBitsSet(AI.AccessWidth, AI.FieldBitStart, 1124 AI.FieldBitStart + AI.TargetBitWidth); 1125 1126 // Apply the mask and OR in to the value to write. 1127 Val = Builder.CreateOr(Builder.CreateAnd(Load, InvMask), Val); 1128 } 1129 1130 // Write the value. 1131 llvm::StoreInst *Store = Builder.CreateStore(Val, Ptr, 1132 Dst.isVolatileQualified()); 1133 if (!AI.AccessAlignment.isZero()) 1134 Store->setAlignment(AI.AccessAlignment.getQuantity()); 1135 } 1136 } 1137 1138 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src, 1139 LValue Dst) { 1140 // This access turns into a read/modify/write of the vector. Load the input 1141 // value now. 1142 llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddr(), 1143 Dst.isVolatileQualified()); 1144 const llvm::Constant *Elts = Dst.getExtVectorElts(); 1145 1146 llvm::Value *SrcVal = Src.getScalarVal(); 1147 1148 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) { 1149 unsigned NumSrcElts = VTy->getNumElements(); 1150 unsigned NumDstElts = 1151 cast<llvm::VectorType>(Vec->getType())->getNumElements(); 1152 if (NumDstElts == NumSrcElts) { 1153 // Use shuffle vector is the src and destination are the same number of 1154 // elements and restore the vector mask since it is on the side it will be 1155 // stored. 1156 SmallVector<llvm::Constant*, 4> Mask(NumDstElts); 1157 for (unsigned i = 0; i != NumSrcElts; ++i) { 1158 unsigned InIdx = getAccessedFieldNo(i, Elts); 1159 Mask[InIdx] = llvm::ConstantInt::get(Int32Ty, i); 1160 } 1161 1162 llvm::Value *MaskV = llvm::ConstantVector::get(Mask); 1163 Vec = Builder.CreateShuffleVector(SrcVal, 1164 llvm::UndefValue::get(Vec->getType()), 1165 MaskV); 1166 } else if (NumDstElts > NumSrcElts) { 1167 // Extended the source vector to the same length and then shuffle it 1168 // into the destination. 1169 // FIXME: since we're shuffling with undef, can we just use the indices 1170 // into that? This could be simpler. 1171 SmallVector<llvm::Constant*, 4> ExtMask; 1172 unsigned i; 1173 for (i = 0; i != NumSrcElts; ++i) 1174 ExtMask.push_back(llvm::ConstantInt::get(Int32Ty, i)); 1175 for (; i != NumDstElts; ++i) 1176 ExtMask.push_back(llvm::UndefValue::get(Int32Ty)); 1177 llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask); 1178 llvm::Value *ExtSrcVal = 1179 Builder.CreateShuffleVector(SrcVal, 1180 llvm::UndefValue::get(SrcVal->getType()), 1181 ExtMaskV); 1182 // build identity 1183 SmallVector<llvm::Constant*, 4> Mask; 1184 for (unsigned i = 0; i != NumDstElts; ++i) 1185 Mask.push_back(llvm::ConstantInt::get(Int32Ty, i)); 1186 1187 // modify when what gets shuffled in 1188 for (unsigned i = 0; i != NumSrcElts; ++i) { 1189 unsigned Idx = getAccessedFieldNo(i, Elts); 1190 Mask[Idx] = llvm::ConstantInt::get(Int32Ty, i+NumDstElts); 1191 } 1192 llvm::Value *MaskV = llvm::ConstantVector::get(Mask); 1193 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV); 1194 } else { 1195 // We should never shorten the vector 1196 llvm_unreachable("unexpected shorten vector length"); 1197 } 1198 } else { 1199 // If the Src is a scalar (not a vector) it must be updating one element. 1200 unsigned InIdx = getAccessedFieldNo(0, Elts); 1201 llvm::Value *Elt = llvm::ConstantInt::get(Int32Ty, InIdx); 1202 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt); 1203 } 1204 1205 Builder.CreateStore(Vec, Dst.getExtVectorAddr(), Dst.isVolatileQualified()); 1206 } 1207 1208 // setObjCGCLValueClass - sets class of he lvalue for the purpose of 1209 // generating write-barries API. It is currently a global, ivar, 1210 // or neither. 1211 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E, 1212 LValue &LV, 1213 bool IsMemberAccess=false) { 1214 if (Ctx.getLangOptions().getGC() == LangOptions::NonGC) 1215 return; 1216 1217 if (isa<ObjCIvarRefExpr>(E)) { 1218 QualType ExpTy = E->getType(); 1219 if (IsMemberAccess && ExpTy->isPointerType()) { 1220 // If ivar is a structure pointer, assigning to field of 1221 // this struct follows gcc's behavior and makes it a non-ivar 1222 // writer-barrier conservatively. 1223 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType(); 1224 if (ExpTy->isRecordType()) { 1225 LV.setObjCIvar(false); 1226 return; 1227 } 1228 } 1229 LV.setObjCIvar(true); 1230 ObjCIvarRefExpr *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr*>(E)); 1231 LV.setBaseIvarExp(Exp->getBase()); 1232 LV.setObjCArray(E->getType()->isArrayType()); 1233 return; 1234 } 1235 1236 if (const DeclRefExpr *Exp = dyn_cast<DeclRefExpr>(E)) { 1237 if (const VarDecl *VD = dyn_cast<VarDecl>(Exp->getDecl())) { 1238 if (VD->hasGlobalStorage()) { 1239 LV.setGlobalObjCRef(true); 1240 LV.setThreadLocalRef(VD->isThreadSpecified()); 1241 } 1242 } 1243 LV.setObjCArray(E->getType()->isArrayType()); 1244 return; 1245 } 1246 1247 if (const UnaryOperator *Exp = dyn_cast<UnaryOperator>(E)) { 1248 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 1249 return; 1250 } 1251 1252 if (const ParenExpr *Exp = dyn_cast<ParenExpr>(E)) { 1253 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 1254 if (LV.isObjCIvar()) { 1255 // If cast is to a structure pointer, follow gcc's behavior and make it 1256 // a non-ivar write-barrier. 1257 QualType ExpTy = E->getType(); 1258 if (ExpTy->isPointerType()) 1259 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType(); 1260 if (ExpTy->isRecordType()) 1261 LV.setObjCIvar(false); 1262 } 1263 return; 1264 } 1265 1266 if (const GenericSelectionExpr *Exp = dyn_cast<GenericSelectionExpr>(E)) { 1267 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV); 1268 return; 1269 } 1270 1271 if (const ImplicitCastExpr *Exp = dyn_cast<ImplicitCastExpr>(E)) { 1272 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 1273 return; 1274 } 1275 1276 if (const CStyleCastExpr *Exp = dyn_cast<CStyleCastExpr>(E)) { 1277 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 1278 return; 1279 } 1280 1281 if (const ObjCBridgedCastExpr *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) { 1282 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 1283 return; 1284 } 1285 1286 if (const ArraySubscriptExpr *Exp = dyn_cast<ArraySubscriptExpr>(E)) { 1287 setObjCGCLValueClass(Ctx, Exp->getBase(), LV); 1288 if (LV.isObjCIvar() && !LV.isObjCArray()) 1289 // Using array syntax to assigning to what an ivar points to is not 1290 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0; 1291 LV.setObjCIvar(false); 1292 else if (LV.isGlobalObjCRef() && !LV.isObjCArray()) 1293 // Using array syntax to assigning to what global points to is not 1294 // same as assigning to the global itself. {id *G;} G[i] = 0; 1295 LV.setGlobalObjCRef(false); 1296 return; 1297 } 1298 1299 if (const MemberExpr *Exp = dyn_cast<MemberExpr>(E)) { 1300 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true); 1301 // We don't know if member is an 'ivar', but this flag is looked at 1302 // only in the context of LV.isObjCIvar(). 1303 LV.setObjCArray(E->getType()->isArrayType()); 1304 return; 1305 } 1306 } 1307 1308 static llvm::Value * 1309 EmitBitCastOfLValueToProperType(CodeGenFunction &CGF, 1310 llvm::Value *V, llvm::Type *IRType, 1311 StringRef Name = StringRef()) { 1312 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace(); 1313 return CGF.Builder.CreateBitCast(V, IRType->getPointerTo(AS), Name); 1314 } 1315 1316 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF, 1317 const Expr *E, const VarDecl *VD) { 1318 assert((VD->hasExternalStorage() || VD->isFileVarDecl()) && 1319 "Var decl must have external storage or be a file var decl!"); 1320 1321 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD); 1322 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType()); 1323 V = EmitBitCastOfLValueToProperType(CGF, V, RealVarTy); 1324 unsigned Alignment = CGF.getContext().getDeclAlign(VD).getQuantity(); 1325 QualType T = E->getType(); 1326 LValue LV; 1327 if (VD->getType()->isReferenceType()) { 1328 llvm::LoadInst *LI = CGF.Builder.CreateLoad(V); 1329 LI->setAlignment(Alignment); 1330 V = LI; 1331 LV = CGF.MakeNaturalAlignAddrLValue(V, T); 1332 } else { 1333 LV = CGF.MakeAddrLValue(V, E->getType(), Alignment); 1334 } 1335 setObjCGCLValueClass(CGF.getContext(), E, LV); 1336 return LV; 1337 } 1338 1339 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF, 1340 const Expr *E, const FunctionDecl *FD) { 1341 llvm::Value *V = CGF.CGM.GetAddrOfFunction(FD); 1342 if (!FD->hasPrototype()) { 1343 if (const FunctionProtoType *Proto = 1344 FD->getType()->getAs<FunctionProtoType>()) { 1345 // Ugly case: for a K&R-style definition, the type of the definition 1346 // isn't the same as the type of a use. Correct for this with a 1347 // bitcast. 1348 QualType NoProtoType = 1349 CGF.getContext().getFunctionNoProtoType(Proto->getResultType()); 1350 NoProtoType = CGF.getContext().getPointerType(NoProtoType); 1351 V = CGF.Builder.CreateBitCast(V, CGF.ConvertType(NoProtoType)); 1352 } 1353 } 1354 unsigned Alignment = CGF.getContext().getDeclAlign(FD).getQuantity(); 1355 return CGF.MakeAddrLValue(V, E->getType(), Alignment); 1356 } 1357 1358 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) { 1359 const NamedDecl *ND = E->getDecl(); 1360 unsigned Alignment = getContext().getDeclAlign(ND).getQuantity(); 1361 QualType T = E->getType(); 1362 1363 if (ND->hasAttr<WeakRefAttr>()) { 1364 const ValueDecl *VD = cast<ValueDecl>(ND); 1365 llvm::Constant *Aliasee = CGM.GetWeakRefReference(VD); 1366 return MakeAddrLValue(Aliasee, E->getType(), Alignment); 1367 } 1368 1369 if (const VarDecl *VD = dyn_cast<VarDecl>(ND)) { 1370 1371 // Check if this is a global variable. 1372 if (VD->hasExternalStorage() || VD->isFileVarDecl()) 1373 return EmitGlobalVarDeclLValue(*this, E, VD); 1374 1375 bool NonGCable = VD->hasLocalStorage() && 1376 !VD->getType()->isReferenceType() && 1377 !VD->hasAttr<BlocksAttr>(); 1378 1379 llvm::Value *V = LocalDeclMap[VD]; 1380 if (!V && VD->isStaticLocal()) 1381 V = CGM.getStaticLocalDeclAddress(VD); 1382 assert(V && "DeclRefExpr not entered in LocalDeclMap?"); 1383 1384 if (VD->hasAttr<BlocksAttr>()) 1385 V = BuildBlockByrefAddress(V, VD); 1386 1387 LValue LV; 1388 if (VD->getType()->isReferenceType()) { 1389 llvm::LoadInst *LI = Builder.CreateLoad(V); 1390 LI->setAlignment(Alignment); 1391 V = LI; 1392 LV = MakeNaturalAlignAddrLValue(V, T); 1393 } else { 1394 LV = MakeAddrLValue(V, T, Alignment); 1395 } 1396 1397 if (NonGCable) { 1398 LV.getQuals().removeObjCGCAttr(); 1399 LV.setNonGC(true); 1400 } 1401 setObjCGCLValueClass(getContext(), E, LV); 1402 return LV; 1403 } 1404 1405 if (const FunctionDecl *fn = dyn_cast<FunctionDecl>(ND)) 1406 return EmitFunctionDeclLValue(*this, E, fn); 1407 1408 llvm_unreachable("Unhandled DeclRefExpr"); 1409 1410 // an invalid LValue, but the assert will 1411 // ensure that this point is never reached. 1412 return LValue(); 1413 } 1414 1415 LValue CodeGenFunction::EmitBlockDeclRefLValue(const BlockDeclRefExpr *E) { 1416 unsigned Alignment = 1417 getContext().getDeclAlign(E->getDecl()).getQuantity(); 1418 return MakeAddrLValue(GetAddrOfBlockDecl(E), E->getType(), Alignment); 1419 } 1420 1421 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) { 1422 // __extension__ doesn't affect lvalue-ness. 1423 if (E->getOpcode() == UO_Extension) 1424 return EmitLValue(E->getSubExpr()); 1425 1426 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType()); 1427 switch (E->getOpcode()) { 1428 default: llvm_unreachable("Unknown unary operator lvalue!"); 1429 case UO_Deref: { 1430 QualType T = E->getSubExpr()->getType()->getPointeeType(); 1431 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type"); 1432 1433 LValue LV = MakeAddrLValue(EmitScalarExpr(E->getSubExpr()), T); 1434 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace()); 1435 1436 // We should not generate __weak write barrier on indirect reference 1437 // of a pointer to object; as in void foo (__weak id *param); *param = 0; 1438 // But, we continue to generate __strong write barrier on indirect write 1439 // into a pointer to object. 1440 if (getContext().getLangOptions().ObjC1 && 1441 getContext().getLangOptions().getGC() != LangOptions::NonGC && 1442 LV.isObjCWeak()) 1443 LV.setNonGC(!E->isOBJCGCCandidate(getContext())); 1444 return LV; 1445 } 1446 case UO_Real: 1447 case UO_Imag: { 1448 LValue LV = EmitLValue(E->getSubExpr()); 1449 assert(LV.isSimple() && "real/imag on non-ordinary l-value"); 1450 llvm::Value *Addr = LV.getAddress(); 1451 1452 // real and imag are valid on scalars. This is a faster way of 1453 // testing that. 1454 if (!cast<llvm::PointerType>(Addr->getType()) 1455 ->getElementType()->isStructTy()) { 1456 assert(E->getSubExpr()->getType()->isArithmeticType()); 1457 return LV; 1458 } 1459 1460 assert(E->getSubExpr()->getType()->isAnyComplexType()); 1461 1462 unsigned Idx = E->getOpcode() == UO_Imag; 1463 return MakeAddrLValue(Builder.CreateStructGEP(LV.getAddress(), 1464 Idx, "idx"), 1465 ExprTy); 1466 } 1467 case UO_PreInc: 1468 case UO_PreDec: { 1469 LValue LV = EmitLValue(E->getSubExpr()); 1470 bool isInc = E->getOpcode() == UO_PreInc; 1471 1472 if (E->getType()->isAnyComplexType()) 1473 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/); 1474 else 1475 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/); 1476 return LV; 1477 } 1478 } 1479 } 1480 1481 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) { 1482 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E), 1483 E->getType()); 1484 } 1485 1486 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) { 1487 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E), 1488 E->getType()); 1489 } 1490 1491 1492 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) { 1493 switch (E->getIdentType()) { 1494 default: 1495 return EmitUnsupportedLValue(E, "predefined expression"); 1496 1497 case PredefinedExpr::Func: 1498 case PredefinedExpr::Function: 1499 case PredefinedExpr::PrettyFunction: { 1500 unsigned Type = E->getIdentType(); 1501 std::string GlobalVarName; 1502 1503 switch (Type) { 1504 default: llvm_unreachable("Invalid type"); 1505 case PredefinedExpr::Func: 1506 GlobalVarName = "__func__."; 1507 break; 1508 case PredefinedExpr::Function: 1509 GlobalVarName = "__FUNCTION__."; 1510 break; 1511 case PredefinedExpr::PrettyFunction: 1512 GlobalVarName = "__PRETTY_FUNCTION__."; 1513 break; 1514 } 1515 1516 StringRef FnName = CurFn->getName(); 1517 if (FnName.startswith("\01")) 1518 FnName = FnName.substr(1); 1519 GlobalVarName += FnName; 1520 1521 const Decl *CurDecl = CurCodeDecl; 1522 if (CurDecl == 0) 1523 CurDecl = getContext().getTranslationUnitDecl(); 1524 1525 std::string FunctionName = 1526 (isa<BlockDecl>(CurDecl) 1527 ? FnName.str() 1528 : PredefinedExpr::ComputeName((PredefinedExpr::IdentType)Type, CurDecl)); 1529 1530 llvm::Constant *C = 1531 CGM.GetAddrOfConstantCString(FunctionName, GlobalVarName.c_str()); 1532 return MakeAddrLValue(C, E->getType()); 1533 } 1534 } 1535 } 1536 1537 llvm::BasicBlock *CodeGenFunction::getTrapBB() { 1538 const CodeGenOptions &GCO = CGM.getCodeGenOpts(); 1539 1540 // If we are not optimzing, don't collapse all calls to trap in the function 1541 // to the same call, that way, in the debugger they can see which operation 1542 // did in fact fail. If we are optimizing, we collapse all calls to trap down 1543 // to just one per function to save on codesize. 1544 if (GCO.OptimizationLevel && TrapBB) 1545 return TrapBB; 1546 1547 llvm::BasicBlock *Cont = 0; 1548 if (HaveInsertPoint()) { 1549 Cont = createBasicBlock("cont"); 1550 EmitBranch(Cont); 1551 } 1552 TrapBB = createBasicBlock("trap"); 1553 EmitBlock(TrapBB); 1554 1555 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::trap); 1556 llvm::CallInst *TrapCall = Builder.CreateCall(F); 1557 TrapCall->setDoesNotReturn(); 1558 TrapCall->setDoesNotThrow(); 1559 Builder.CreateUnreachable(); 1560 1561 if (Cont) 1562 EmitBlock(Cont); 1563 return TrapBB; 1564 } 1565 1566 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an 1567 /// array to pointer, return the array subexpression. 1568 static const Expr *isSimpleArrayDecayOperand(const Expr *E) { 1569 // If this isn't just an array->pointer decay, bail out. 1570 const CastExpr *CE = dyn_cast<CastExpr>(E); 1571 if (CE == 0 || CE->getCastKind() != CK_ArrayToPointerDecay) 1572 return 0; 1573 1574 // If this is a decay from variable width array, bail out. 1575 const Expr *SubExpr = CE->getSubExpr(); 1576 if (SubExpr->getType()->isVariableArrayType()) 1577 return 0; 1578 1579 return SubExpr; 1580 } 1581 1582 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E) { 1583 // The index must always be an integer, which is not an aggregate. Emit it. 1584 llvm::Value *Idx = EmitScalarExpr(E->getIdx()); 1585 QualType IdxTy = E->getIdx()->getType(); 1586 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType(); 1587 1588 // If the base is a vector type, then we are forming a vector element lvalue 1589 // with this subscript. 1590 if (E->getBase()->getType()->isVectorType()) { 1591 // Emit the vector as an lvalue to get its address. 1592 LValue LHS = EmitLValue(E->getBase()); 1593 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!"); 1594 Idx = Builder.CreateIntCast(Idx, Int32Ty, IdxSigned, "vidx"); 1595 return LValue::MakeVectorElt(LHS.getAddress(), Idx, 1596 E->getBase()->getType()); 1597 } 1598 1599 // Extend or truncate the index type to 32 or 64-bits. 1600 if (Idx->getType() != IntPtrTy) 1601 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom"); 1602 1603 // FIXME: As llvm implements the object size checking, this can come out. 1604 if (CatchUndefined) { 1605 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E->getBase())){ 1606 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr())) { 1607 if (ICE->getCastKind() == CK_ArrayToPointerDecay) { 1608 if (const ConstantArrayType *CAT 1609 = getContext().getAsConstantArrayType(DRE->getType())) { 1610 llvm::APInt Size = CAT->getSize(); 1611 llvm::BasicBlock *Cont = createBasicBlock("cont"); 1612 Builder.CreateCondBr(Builder.CreateICmpULE(Idx, 1613 llvm::ConstantInt::get(Idx->getType(), Size)), 1614 Cont, getTrapBB()); 1615 EmitBlock(Cont); 1616 } 1617 } 1618 } 1619 } 1620 } 1621 1622 // We know that the pointer points to a type of the correct size, unless the 1623 // size is a VLA or Objective-C interface. 1624 llvm::Value *Address = 0; 1625 unsigned ArrayAlignment = 0; 1626 if (const VariableArrayType *vla = 1627 getContext().getAsVariableArrayType(E->getType())) { 1628 // The base must be a pointer, which is not an aggregate. Emit 1629 // it. It needs to be emitted first in case it's what captures 1630 // the VLA bounds. 1631 Address = EmitScalarExpr(E->getBase()); 1632 1633 // The element count here is the total number of non-VLA elements. 1634 llvm::Value *numElements = getVLASize(vla).first; 1635 1636 // Effectively, the multiply by the VLA size is part of the GEP. 1637 // GEP indexes are signed, and scaling an index isn't permitted to 1638 // signed-overflow, so we use the same semantics for our explicit 1639 // multiply. We suppress this if overflow is not undefined behavior. 1640 if (getLangOptions().isSignedOverflowDefined()) { 1641 Idx = Builder.CreateMul(Idx, numElements); 1642 Address = Builder.CreateGEP(Address, Idx, "arrayidx"); 1643 } else { 1644 Idx = Builder.CreateNSWMul(Idx, numElements); 1645 Address = Builder.CreateInBoundsGEP(Address, Idx, "arrayidx"); 1646 } 1647 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){ 1648 // Indexing over an interface, as in "NSString *P; P[4];" 1649 llvm::Value *InterfaceSize = 1650 llvm::ConstantInt::get(Idx->getType(), 1651 getContext().getTypeSizeInChars(OIT).getQuantity()); 1652 1653 Idx = Builder.CreateMul(Idx, InterfaceSize); 1654 1655 // The base must be a pointer, which is not an aggregate. Emit it. 1656 llvm::Value *Base = EmitScalarExpr(E->getBase()); 1657 Address = EmitCastToVoidPtr(Base); 1658 Address = Builder.CreateGEP(Address, Idx, "arrayidx"); 1659 Address = Builder.CreateBitCast(Address, Base->getType()); 1660 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) { 1661 // If this is A[i] where A is an array, the frontend will have decayed the 1662 // base to be a ArrayToPointerDecay implicit cast. While correct, it is 1663 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a 1664 // "gep x, i" here. Emit one "gep A, 0, i". 1665 assert(Array->getType()->isArrayType() && 1666 "Array to pointer decay must have array source type!"); 1667 LValue ArrayLV = EmitLValue(Array); 1668 llvm::Value *ArrayPtr = ArrayLV.getAddress(); 1669 llvm::Value *Zero = llvm::ConstantInt::get(Int32Ty, 0); 1670 llvm::Value *Args[] = { Zero, Idx }; 1671 1672 // Propagate the alignment from the array itself to the result. 1673 ArrayAlignment = ArrayLV.getAlignment(); 1674 1675 if (getContext().getLangOptions().isSignedOverflowDefined()) 1676 Address = Builder.CreateGEP(ArrayPtr, Args, "arrayidx"); 1677 else 1678 Address = Builder.CreateInBoundsGEP(ArrayPtr, Args, "arrayidx"); 1679 } else { 1680 // The base must be a pointer, which is not an aggregate. Emit it. 1681 llvm::Value *Base = EmitScalarExpr(E->getBase()); 1682 if (getContext().getLangOptions().isSignedOverflowDefined()) 1683 Address = Builder.CreateGEP(Base, Idx, "arrayidx"); 1684 else 1685 Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx"); 1686 } 1687 1688 QualType T = E->getBase()->getType()->getPointeeType(); 1689 assert(!T.isNull() && 1690 "CodeGenFunction::EmitArraySubscriptExpr(): Illegal base type"); 1691 1692 // Limit the alignment to that of the result type. 1693 if (ArrayAlignment) { 1694 unsigned Align = getContext().getTypeAlignInChars(T).getQuantity(); 1695 ArrayAlignment = std::min(Align, ArrayAlignment); 1696 } 1697 1698 LValue LV = MakeAddrLValue(Address, T, ArrayAlignment); 1699 LV.getQuals().setAddressSpace(E->getBase()->getType().getAddressSpace()); 1700 1701 if (getContext().getLangOptions().ObjC1 && 1702 getContext().getLangOptions().getGC() != LangOptions::NonGC) { 1703 LV.setNonGC(!E->isOBJCGCCandidate(getContext())); 1704 setObjCGCLValueClass(getContext(), E, LV); 1705 } 1706 return LV; 1707 } 1708 1709 static 1710 llvm::Constant *GenerateConstantVector(llvm::LLVMContext &VMContext, 1711 SmallVector<unsigned, 4> &Elts) { 1712 SmallVector<llvm::Constant*, 4> CElts; 1713 1714 llvm::Type *Int32Ty = llvm::Type::getInt32Ty(VMContext); 1715 for (unsigned i = 0, e = Elts.size(); i != e; ++i) 1716 CElts.push_back(llvm::ConstantInt::get(Int32Ty, Elts[i])); 1717 1718 return llvm::ConstantVector::get(CElts); 1719 } 1720 1721 LValue CodeGenFunction:: 1722 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) { 1723 // Emit the base vector as an l-value. 1724 LValue Base; 1725 1726 // ExtVectorElementExpr's base can either be a vector or pointer to vector. 1727 if (E->isArrow()) { 1728 // If it is a pointer to a vector, emit the address and form an lvalue with 1729 // it. 1730 llvm::Value *Ptr = EmitScalarExpr(E->getBase()); 1731 const PointerType *PT = E->getBase()->getType()->getAs<PointerType>(); 1732 Base = MakeAddrLValue(Ptr, PT->getPointeeType()); 1733 Base.getQuals().removeObjCGCAttr(); 1734 } else if (E->getBase()->isGLValue()) { 1735 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x), 1736 // emit the base as an lvalue. 1737 assert(E->getBase()->getType()->isVectorType()); 1738 Base = EmitLValue(E->getBase()); 1739 } else { 1740 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such. 1741 assert(E->getBase()->getType()->isVectorType() && 1742 "Result must be a vector"); 1743 llvm::Value *Vec = EmitScalarExpr(E->getBase()); 1744 1745 // Store the vector to memory (because LValue wants an address). 1746 llvm::Value *VecMem = CreateMemTemp(E->getBase()->getType()); 1747 Builder.CreateStore(Vec, VecMem); 1748 Base = MakeAddrLValue(VecMem, E->getBase()->getType()); 1749 } 1750 1751 QualType type = 1752 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers()); 1753 1754 // Encode the element access list into a vector of unsigned indices. 1755 SmallVector<unsigned, 4> Indices; 1756 E->getEncodedElementAccess(Indices); 1757 1758 if (Base.isSimple()) { 1759 llvm::Constant *CV = GenerateConstantVector(getLLVMContext(), Indices); 1760 return LValue::MakeExtVectorElt(Base.getAddress(), CV, type); 1761 } 1762 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!"); 1763 1764 llvm::Constant *BaseElts = Base.getExtVectorElts(); 1765 SmallVector<llvm::Constant *, 4> CElts; 1766 1767 for (unsigned i = 0, e = Indices.size(); i != e; ++i) { 1768 if (isa<llvm::ConstantAggregateZero>(BaseElts)) 1769 CElts.push_back(llvm::ConstantInt::get(Int32Ty, 0)); 1770 else 1771 CElts.push_back(cast<llvm::Constant>(BaseElts->getOperand(Indices[i]))); 1772 } 1773 llvm::Constant *CV = llvm::ConstantVector::get(CElts); 1774 return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV, type); 1775 } 1776 1777 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) { 1778 bool isNonGC = false; 1779 Expr *BaseExpr = E->getBase(); 1780 llvm::Value *BaseValue = NULL; 1781 Qualifiers BaseQuals; 1782 1783 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar. 1784 if (E->isArrow()) { 1785 BaseValue = EmitScalarExpr(BaseExpr); 1786 const PointerType *PTy = 1787 BaseExpr->getType()->getAs<PointerType>(); 1788 BaseQuals = PTy->getPointeeType().getQualifiers(); 1789 } else { 1790 LValue BaseLV = EmitLValue(BaseExpr); 1791 if (BaseLV.isNonGC()) 1792 isNonGC = true; 1793 // FIXME: this isn't right for bitfields. 1794 BaseValue = BaseLV.getAddress(); 1795 QualType BaseTy = BaseExpr->getType(); 1796 BaseQuals = BaseTy.getQualifiers(); 1797 } 1798 1799 NamedDecl *ND = E->getMemberDecl(); 1800 if (FieldDecl *Field = dyn_cast<FieldDecl>(ND)) { 1801 LValue LV = EmitLValueForField(BaseValue, Field, 1802 BaseQuals.getCVRQualifiers()); 1803 LV.setNonGC(isNonGC); 1804 setObjCGCLValueClass(getContext(), E, LV); 1805 return LV; 1806 } 1807 1808 if (VarDecl *VD = dyn_cast<VarDecl>(ND)) 1809 return EmitGlobalVarDeclLValue(*this, E, VD); 1810 1811 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) 1812 return EmitFunctionDeclLValue(*this, E, FD); 1813 1814 llvm_unreachable("Unhandled member declaration!"); 1815 } 1816 1817 LValue CodeGenFunction::EmitLValueForBitfield(llvm::Value *BaseValue, 1818 const FieldDecl *Field, 1819 unsigned CVRQualifiers) { 1820 const CGRecordLayout &RL = 1821 CGM.getTypes().getCGRecordLayout(Field->getParent()); 1822 const CGBitFieldInfo &Info = RL.getBitFieldInfo(Field); 1823 return LValue::MakeBitfield(BaseValue, Info, 1824 Field->getType().withCVRQualifiers(CVRQualifiers)); 1825 } 1826 1827 /// EmitLValueForAnonRecordField - Given that the field is a member of 1828 /// an anonymous struct or union buried inside a record, and given 1829 /// that the base value is a pointer to the enclosing record, derive 1830 /// an lvalue for the ultimate field. 1831 LValue CodeGenFunction::EmitLValueForAnonRecordField(llvm::Value *BaseValue, 1832 const IndirectFieldDecl *Field, 1833 unsigned CVRQualifiers) { 1834 IndirectFieldDecl::chain_iterator I = Field->chain_begin(), 1835 IEnd = Field->chain_end(); 1836 while (true) { 1837 LValue LV = EmitLValueForField(BaseValue, cast<FieldDecl>(*I), 1838 CVRQualifiers); 1839 if (++I == IEnd) return LV; 1840 1841 assert(LV.isSimple()); 1842 BaseValue = LV.getAddress(); 1843 CVRQualifiers |= LV.getVRQualifiers(); 1844 } 1845 } 1846 1847 LValue CodeGenFunction::EmitLValueForField(llvm::Value *baseAddr, 1848 const FieldDecl *field, 1849 unsigned cvr) { 1850 if (field->isBitField()) 1851 return EmitLValueForBitfield(baseAddr, field, cvr); 1852 1853 const RecordDecl *rec = field->getParent(); 1854 QualType type = field->getType(); 1855 unsigned alignment = getContext().getDeclAlign(field).getQuantity(); 1856 1857 bool mayAlias = rec->hasAttr<MayAliasAttr>(); 1858 1859 llvm::Value *addr = baseAddr; 1860 if (rec->isUnion()) { 1861 // For unions, there is no pointer adjustment. 1862 assert(!type->isReferenceType() && "union has reference member"); 1863 } else { 1864 // For structs, we GEP to the field that the record layout suggests. 1865 unsigned idx = CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field); 1866 addr = Builder.CreateStructGEP(addr, idx, field->getName()); 1867 1868 // If this is a reference field, load the reference right now. 1869 if (const ReferenceType *refType = type->getAs<ReferenceType>()) { 1870 llvm::LoadInst *load = Builder.CreateLoad(addr, "ref"); 1871 if (cvr & Qualifiers::Volatile) load->setVolatile(true); 1872 load->setAlignment(alignment); 1873 1874 if (CGM.shouldUseTBAA()) { 1875 llvm::MDNode *tbaa; 1876 if (mayAlias) 1877 tbaa = CGM.getTBAAInfo(getContext().CharTy); 1878 else 1879 tbaa = CGM.getTBAAInfo(type); 1880 CGM.DecorateInstruction(load, tbaa); 1881 } 1882 1883 addr = load; 1884 mayAlias = false; 1885 type = refType->getPointeeType(); 1886 if (type->isIncompleteType()) 1887 alignment = 0; 1888 else 1889 alignment = getContext().getTypeAlignInChars(type).getQuantity(); 1890 cvr = 0; // qualifiers don't recursively apply to referencee 1891 } 1892 } 1893 1894 // Make sure that the address is pointing to the right type. This is critical 1895 // for both unions and structs. A union needs a bitcast, a struct element 1896 // will need a bitcast if the LLVM type laid out doesn't match the desired 1897 // type. 1898 addr = EmitBitCastOfLValueToProperType(*this, addr, 1899 CGM.getTypes().ConvertTypeForMem(type), 1900 field->getName()); 1901 1902 if (field->hasAttr<AnnotateAttr>()) 1903 addr = EmitFieldAnnotations(field, addr); 1904 1905 LValue LV = MakeAddrLValue(addr, type, alignment); 1906 LV.getQuals().addCVRQualifiers(cvr); 1907 1908 // __weak attribute on a field is ignored. 1909 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak) 1910 LV.getQuals().removeObjCGCAttr(); 1911 1912 // Fields of may_alias structs act like 'char' for TBAA purposes. 1913 // FIXME: this should get propagated down through anonymous structs 1914 // and unions. 1915 if (mayAlias && LV.getTBAAInfo()) 1916 LV.setTBAAInfo(CGM.getTBAAInfo(getContext().CharTy)); 1917 1918 return LV; 1919 } 1920 1921 LValue 1922 CodeGenFunction::EmitLValueForFieldInitialization(llvm::Value *BaseValue, 1923 const FieldDecl *Field, 1924 unsigned CVRQualifiers) { 1925 QualType FieldType = Field->getType(); 1926 1927 if (!FieldType->isReferenceType()) 1928 return EmitLValueForField(BaseValue, Field, CVRQualifiers); 1929 1930 const CGRecordLayout &RL = 1931 CGM.getTypes().getCGRecordLayout(Field->getParent()); 1932 unsigned idx = RL.getLLVMFieldNo(Field); 1933 llvm::Value *V = Builder.CreateStructGEP(BaseValue, idx); 1934 assert(!FieldType.getObjCGCAttr() && "fields cannot have GC attrs"); 1935 1936 1937 // Make sure that the address is pointing to the right type. This is critical 1938 // for both unions and structs. A union needs a bitcast, a struct element 1939 // will need a bitcast if the LLVM type laid out doesn't match the desired 1940 // type. 1941 llvm::Type *llvmType = ConvertTypeForMem(FieldType); 1942 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace(); 1943 V = Builder.CreateBitCast(V, llvmType->getPointerTo(AS)); 1944 1945 unsigned Alignment = getContext().getDeclAlign(Field).getQuantity(); 1946 return MakeAddrLValue(V, FieldType, Alignment); 1947 } 1948 1949 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){ 1950 llvm::Value *DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral"); 1951 const Expr *InitExpr = E->getInitializer(); 1952 LValue Result = MakeAddrLValue(DeclPtr, E->getType()); 1953 1954 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(), 1955 /*Init*/ true); 1956 1957 return Result; 1958 } 1959 1960 LValue CodeGenFunction:: 1961 EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) { 1962 if (!expr->isGLValue()) { 1963 // ?: here should be an aggregate. 1964 assert((hasAggregateLLVMType(expr->getType()) && 1965 !expr->getType()->isAnyComplexType()) && 1966 "Unexpected conditional operator!"); 1967 return EmitAggExprToLValue(expr); 1968 } 1969 1970 const Expr *condExpr = expr->getCond(); 1971 bool CondExprBool; 1972 if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) { 1973 const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr(); 1974 if (!CondExprBool) std::swap(live, dead); 1975 1976 if (!ContainsLabel(dead)) 1977 return EmitLValue(live); 1978 } 1979 1980 OpaqueValueMapping binding(*this, expr); 1981 1982 llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true"); 1983 llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false"); 1984 llvm::BasicBlock *contBlock = createBasicBlock("cond.end"); 1985 1986 ConditionalEvaluation eval(*this); 1987 EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock); 1988 1989 // Any temporaries created here are conditional. 1990 EmitBlock(lhsBlock); 1991 eval.begin(*this); 1992 LValue lhs = EmitLValue(expr->getTrueExpr()); 1993 eval.end(*this); 1994 1995 if (!lhs.isSimple()) 1996 return EmitUnsupportedLValue(expr, "conditional operator"); 1997 1998 lhsBlock = Builder.GetInsertBlock(); 1999 Builder.CreateBr(contBlock); 2000 2001 // Any temporaries created here are conditional. 2002 EmitBlock(rhsBlock); 2003 eval.begin(*this); 2004 LValue rhs = EmitLValue(expr->getFalseExpr()); 2005 eval.end(*this); 2006 if (!rhs.isSimple()) 2007 return EmitUnsupportedLValue(expr, "conditional operator"); 2008 rhsBlock = Builder.GetInsertBlock(); 2009 2010 EmitBlock(contBlock); 2011 2012 llvm::PHINode *phi = Builder.CreatePHI(lhs.getAddress()->getType(), 2, 2013 "cond-lvalue"); 2014 phi->addIncoming(lhs.getAddress(), lhsBlock); 2015 phi->addIncoming(rhs.getAddress(), rhsBlock); 2016 return MakeAddrLValue(phi, expr->getType()); 2017 } 2018 2019 /// EmitCastLValue - Casts are never lvalues unless that cast is a dynamic_cast. 2020 /// If the cast is a dynamic_cast, we can have the usual lvalue result, 2021 /// otherwise if a cast is needed by the code generator in an lvalue context, 2022 /// then it must mean that we need the address of an aggregate in order to 2023 /// access one of its fields. This can happen for all the reasons that casts 2024 /// are permitted with aggregate result, including noop aggregate casts, and 2025 /// cast from scalar to union. 2026 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) { 2027 switch (E->getCastKind()) { 2028 case CK_ToVoid: 2029 return EmitUnsupportedLValue(E, "unexpected cast lvalue"); 2030 2031 case CK_Dependent: 2032 llvm_unreachable("dependent cast kind in IR gen!"); 2033 2034 case CK_NoOp: 2035 case CK_LValueToRValue: 2036 if (!E->getSubExpr()->Classify(getContext()).isPRValue() 2037 || E->getType()->isRecordType()) 2038 return EmitLValue(E->getSubExpr()); 2039 // Fall through to synthesize a temporary. 2040 2041 case CK_BitCast: 2042 case CK_ArrayToPointerDecay: 2043 case CK_FunctionToPointerDecay: 2044 case CK_NullToMemberPointer: 2045 case CK_NullToPointer: 2046 case CK_IntegralToPointer: 2047 case CK_PointerToIntegral: 2048 case CK_PointerToBoolean: 2049 case CK_VectorSplat: 2050 case CK_IntegralCast: 2051 case CK_IntegralToBoolean: 2052 case CK_IntegralToFloating: 2053 case CK_FloatingToIntegral: 2054 case CK_FloatingToBoolean: 2055 case CK_FloatingCast: 2056 case CK_FloatingRealToComplex: 2057 case CK_FloatingComplexToReal: 2058 case CK_FloatingComplexToBoolean: 2059 case CK_FloatingComplexCast: 2060 case CK_FloatingComplexToIntegralComplex: 2061 case CK_IntegralRealToComplex: 2062 case CK_IntegralComplexToReal: 2063 case CK_IntegralComplexToBoolean: 2064 case CK_IntegralComplexCast: 2065 case CK_IntegralComplexToFloatingComplex: 2066 case CK_DerivedToBaseMemberPointer: 2067 case CK_BaseToDerivedMemberPointer: 2068 case CK_MemberPointerToBoolean: 2069 case CK_AnyPointerToBlockPointerCast: 2070 case CK_ARCProduceObject: 2071 case CK_ARCConsumeObject: 2072 case CK_ARCReclaimReturnedObject: 2073 case CK_ARCExtendBlockObject: { 2074 // These casts only produce lvalues when we're binding a reference to a 2075 // temporary realized from a (converted) pure rvalue. Emit the expression 2076 // as a value, copy it into a temporary, and return an lvalue referring to 2077 // that temporary. 2078 llvm::Value *V = CreateMemTemp(E->getType(), "ref.temp"); 2079 EmitAnyExprToMem(E, V, E->getType().getQualifiers(), false); 2080 return MakeAddrLValue(V, E->getType()); 2081 } 2082 2083 case CK_Dynamic: { 2084 LValue LV = EmitLValue(E->getSubExpr()); 2085 llvm::Value *V = LV.getAddress(); 2086 const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(E); 2087 return MakeAddrLValue(EmitDynamicCast(V, DCE), E->getType()); 2088 } 2089 2090 case CK_ConstructorConversion: 2091 case CK_UserDefinedConversion: 2092 case CK_CPointerToObjCPointerCast: 2093 case CK_BlockPointerToObjCPointerCast: 2094 return EmitLValue(E->getSubExpr()); 2095 2096 case CK_UncheckedDerivedToBase: 2097 case CK_DerivedToBase: { 2098 const RecordType *DerivedClassTy = 2099 E->getSubExpr()->getType()->getAs<RecordType>(); 2100 CXXRecordDecl *DerivedClassDecl = 2101 cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 2102 2103 LValue LV = EmitLValue(E->getSubExpr()); 2104 llvm::Value *This = LV.getAddress(); 2105 2106 // Perform the derived-to-base conversion 2107 llvm::Value *Base = 2108 GetAddressOfBaseClass(This, DerivedClassDecl, 2109 E->path_begin(), E->path_end(), 2110 /*NullCheckValue=*/false); 2111 2112 return MakeAddrLValue(Base, E->getType()); 2113 } 2114 case CK_ToUnion: 2115 return EmitAggExprToLValue(E); 2116 case CK_BaseToDerived: { 2117 const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>(); 2118 CXXRecordDecl *DerivedClassDecl = 2119 cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 2120 2121 LValue LV = EmitLValue(E->getSubExpr()); 2122 2123 // Perform the base-to-derived conversion 2124 llvm::Value *Derived = 2125 GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl, 2126 E->path_begin(), E->path_end(), 2127 /*NullCheckValue=*/false); 2128 2129 return MakeAddrLValue(Derived, E->getType()); 2130 } 2131 case CK_LValueBitCast: { 2132 // This must be a reinterpret_cast (or c-style equivalent). 2133 const ExplicitCastExpr *CE = cast<ExplicitCastExpr>(E); 2134 2135 LValue LV = EmitLValue(E->getSubExpr()); 2136 llvm::Value *V = Builder.CreateBitCast(LV.getAddress(), 2137 ConvertType(CE->getTypeAsWritten())); 2138 return MakeAddrLValue(V, E->getType()); 2139 } 2140 case CK_ObjCObjectLValueCast: { 2141 LValue LV = EmitLValue(E->getSubExpr()); 2142 QualType ToType = getContext().getLValueReferenceType(E->getType()); 2143 llvm::Value *V = Builder.CreateBitCast(LV.getAddress(), 2144 ConvertType(ToType)); 2145 return MakeAddrLValue(V, E->getType()); 2146 } 2147 } 2148 2149 llvm_unreachable("Unhandled lvalue cast kind?"); 2150 } 2151 2152 LValue CodeGenFunction::EmitNullInitializationLValue( 2153 const CXXScalarValueInitExpr *E) { 2154 QualType Ty = E->getType(); 2155 LValue LV = MakeAddrLValue(CreateMemTemp(Ty), Ty); 2156 EmitNullInitialization(LV.getAddress(), Ty); 2157 return LV; 2158 } 2159 2160 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) { 2161 assert(OpaqueValueMappingData::shouldBindAsLValue(e)); 2162 return getOpaqueLValueMapping(e); 2163 } 2164 2165 LValue CodeGenFunction::EmitMaterializeTemporaryExpr( 2166 const MaterializeTemporaryExpr *E) { 2167 RValue RV = EmitReferenceBindingToExpr(E, /*InitializedDecl=*/0); 2168 return MakeAddrLValue(RV.getScalarVal(), E->getType()); 2169 } 2170 2171 2172 //===--------------------------------------------------------------------===// 2173 // Expression Emission 2174 //===--------------------------------------------------------------------===// 2175 2176 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E, 2177 ReturnValueSlot ReturnValue) { 2178 if (CGDebugInfo *DI = getDebugInfo()) 2179 DI->EmitLocation(Builder, E->getLocStart()); 2180 2181 // Builtins never have block type. 2182 if (E->getCallee()->getType()->isBlockPointerType()) 2183 return EmitBlockCallExpr(E, ReturnValue); 2184 2185 if (const CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(E)) 2186 return EmitCXXMemberCallExpr(CE, ReturnValue); 2187 2188 if (const CUDAKernelCallExpr *CE = dyn_cast<CUDAKernelCallExpr>(E)) 2189 return EmitCUDAKernelCallExpr(CE, ReturnValue); 2190 2191 const Decl *TargetDecl = E->getCalleeDecl(); 2192 if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl)) { 2193 if (unsigned builtinID = FD->getBuiltinID()) 2194 return EmitBuiltinExpr(FD, builtinID, E); 2195 } 2196 2197 if (const CXXOperatorCallExpr *CE = dyn_cast<CXXOperatorCallExpr>(E)) 2198 if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(TargetDecl)) 2199 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue); 2200 2201 if (const CXXPseudoDestructorExpr *PseudoDtor 2202 = dyn_cast<CXXPseudoDestructorExpr>(E->getCallee()->IgnoreParens())) { 2203 QualType DestroyedType = PseudoDtor->getDestroyedType(); 2204 if (getContext().getLangOptions().ObjCAutoRefCount && 2205 DestroyedType->isObjCLifetimeType() && 2206 (DestroyedType.getObjCLifetime() == Qualifiers::OCL_Strong || 2207 DestroyedType.getObjCLifetime() == Qualifiers::OCL_Weak)) { 2208 // Automatic Reference Counting: 2209 // If the pseudo-expression names a retainable object with weak or 2210 // strong lifetime, the object shall be released. 2211 Expr *BaseExpr = PseudoDtor->getBase(); 2212 llvm::Value *BaseValue = NULL; 2213 Qualifiers BaseQuals; 2214 2215 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar. 2216 if (PseudoDtor->isArrow()) { 2217 BaseValue = EmitScalarExpr(BaseExpr); 2218 const PointerType *PTy = BaseExpr->getType()->getAs<PointerType>(); 2219 BaseQuals = PTy->getPointeeType().getQualifiers(); 2220 } else { 2221 LValue BaseLV = EmitLValue(BaseExpr); 2222 BaseValue = BaseLV.getAddress(); 2223 QualType BaseTy = BaseExpr->getType(); 2224 BaseQuals = BaseTy.getQualifiers(); 2225 } 2226 2227 switch (PseudoDtor->getDestroyedType().getObjCLifetime()) { 2228 case Qualifiers::OCL_None: 2229 case Qualifiers::OCL_ExplicitNone: 2230 case Qualifiers::OCL_Autoreleasing: 2231 break; 2232 2233 case Qualifiers::OCL_Strong: 2234 EmitARCRelease(Builder.CreateLoad(BaseValue, 2235 PseudoDtor->getDestroyedType().isVolatileQualified()), 2236 /*precise*/ true); 2237 break; 2238 2239 case Qualifiers::OCL_Weak: 2240 EmitARCDestroyWeak(BaseValue); 2241 break; 2242 } 2243 } else { 2244 // C++ [expr.pseudo]p1: 2245 // The result shall only be used as the operand for the function call 2246 // operator (), and the result of such a call has type void. The only 2247 // effect is the evaluation of the postfix-expression before the dot or 2248 // arrow. 2249 EmitScalarExpr(E->getCallee()); 2250 } 2251 2252 return RValue::get(0); 2253 } 2254 2255 llvm::Value *Callee = EmitScalarExpr(E->getCallee()); 2256 return EmitCall(E->getCallee()->getType(), Callee, ReturnValue, 2257 E->arg_begin(), E->arg_end(), TargetDecl); 2258 } 2259 2260 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) { 2261 // Comma expressions just emit their LHS then their RHS as an l-value. 2262 if (E->getOpcode() == BO_Comma) { 2263 EmitIgnoredExpr(E->getLHS()); 2264 EnsureInsertPoint(); 2265 return EmitLValue(E->getRHS()); 2266 } 2267 2268 if (E->getOpcode() == BO_PtrMemD || 2269 E->getOpcode() == BO_PtrMemI) 2270 return EmitPointerToDataMemberBinaryExpr(E); 2271 2272 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value"); 2273 2274 // Note that in all of these cases, __block variables need the RHS 2275 // evaluated first just in case the variable gets moved by the RHS. 2276 2277 if (!hasAggregateLLVMType(E->getType())) { 2278 switch (E->getLHS()->getType().getObjCLifetime()) { 2279 case Qualifiers::OCL_Strong: 2280 return EmitARCStoreStrong(E, /*ignored*/ false).first; 2281 2282 case Qualifiers::OCL_Autoreleasing: 2283 return EmitARCStoreAutoreleasing(E).first; 2284 2285 // No reason to do any of these differently. 2286 case Qualifiers::OCL_None: 2287 case Qualifiers::OCL_ExplicitNone: 2288 case Qualifiers::OCL_Weak: 2289 break; 2290 } 2291 2292 RValue RV = EmitAnyExpr(E->getRHS()); 2293 LValue LV = EmitLValue(E->getLHS()); 2294 EmitStoreThroughLValue(RV, LV); 2295 return LV; 2296 } 2297 2298 if (E->getType()->isAnyComplexType()) 2299 return EmitComplexAssignmentLValue(E); 2300 2301 return EmitAggExprToLValue(E); 2302 } 2303 2304 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) { 2305 RValue RV = EmitCallExpr(E); 2306 2307 if (!RV.isScalar()) 2308 return MakeAddrLValue(RV.getAggregateAddr(), E->getType()); 2309 2310 assert(E->getCallReturnType()->isReferenceType() && 2311 "Can't have a scalar return unless the return type is a " 2312 "reference type!"); 2313 2314 return MakeAddrLValue(RV.getScalarVal(), E->getType()); 2315 } 2316 2317 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) { 2318 // FIXME: This shouldn't require another copy. 2319 return EmitAggExprToLValue(E); 2320 } 2321 2322 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) { 2323 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor() 2324 && "binding l-value to type which needs a temporary"); 2325 AggValueSlot Slot = CreateAggTemp(E->getType()); 2326 EmitCXXConstructExpr(E, Slot); 2327 return MakeAddrLValue(Slot.getAddr(), E->getType()); 2328 } 2329 2330 LValue 2331 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) { 2332 return MakeAddrLValue(EmitCXXTypeidExpr(E), E->getType()); 2333 } 2334 2335 LValue 2336 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) { 2337 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue"); 2338 Slot.setExternallyDestructed(); 2339 EmitAggExpr(E->getSubExpr(), Slot); 2340 EmitCXXTemporary(E->getTemporary(), Slot.getAddr()); 2341 return MakeAddrLValue(Slot.getAddr(), E->getType()); 2342 } 2343 2344 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) { 2345 RValue RV = EmitObjCMessageExpr(E); 2346 2347 if (!RV.isScalar()) 2348 return MakeAddrLValue(RV.getAggregateAddr(), E->getType()); 2349 2350 assert(E->getMethodDecl()->getResultType()->isReferenceType() && 2351 "Can't have a scalar return unless the return type is a " 2352 "reference type!"); 2353 2354 return MakeAddrLValue(RV.getScalarVal(), E->getType()); 2355 } 2356 2357 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) { 2358 llvm::Value *V = 2359 CGM.getObjCRuntime().GetSelector(Builder, E->getSelector(), true); 2360 return MakeAddrLValue(V, E->getType()); 2361 } 2362 2363 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface, 2364 const ObjCIvarDecl *Ivar) { 2365 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar); 2366 } 2367 2368 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy, 2369 llvm::Value *BaseValue, 2370 const ObjCIvarDecl *Ivar, 2371 unsigned CVRQualifiers) { 2372 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue, 2373 Ivar, CVRQualifiers); 2374 } 2375 2376 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) { 2377 // FIXME: A lot of the code below could be shared with EmitMemberExpr. 2378 llvm::Value *BaseValue = 0; 2379 const Expr *BaseExpr = E->getBase(); 2380 Qualifiers BaseQuals; 2381 QualType ObjectTy; 2382 if (E->isArrow()) { 2383 BaseValue = EmitScalarExpr(BaseExpr); 2384 ObjectTy = BaseExpr->getType()->getPointeeType(); 2385 BaseQuals = ObjectTy.getQualifiers(); 2386 } else { 2387 LValue BaseLV = EmitLValue(BaseExpr); 2388 // FIXME: this isn't right for bitfields. 2389 BaseValue = BaseLV.getAddress(); 2390 ObjectTy = BaseExpr->getType(); 2391 BaseQuals = ObjectTy.getQualifiers(); 2392 } 2393 2394 LValue LV = 2395 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(), 2396 BaseQuals.getCVRQualifiers()); 2397 setObjCGCLValueClass(getContext(), E, LV); 2398 return LV; 2399 } 2400 2401 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) { 2402 // Can only get l-value for message expression returning aggregate type 2403 RValue RV = EmitAnyExprToTemp(E); 2404 return MakeAddrLValue(RV.getAggregateAddr(), E->getType()); 2405 } 2406 2407 RValue CodeGenFunction::EmitCall(QualType CalleeType, llvm::Value *Callee, 2408 ReturnValueSlot ReturnValue, 2409 CallExpr::const_arg_iterator ArgBeg, 2410 CallExpr::const_arg_iterator ArgEnd, 2411 const Decl *TargetDecl) { 2412 // Get the actual function type. The callee type will always be a pointer to 2413 // function type or a block pointer type. 2414 assert(CalleeType->isFunctionPointerType() && 2415 "Call must have function pointer type!"); 2416 2417 CalleeType = getContext().getCanonicalType(CalleeType); 2418 2419 const FunctionType *FnType 2420 = cast<FunctionType>(cast<PointerType>(CalleeType)->getPointeeType()); 2421 2422 CallArgList Args; 2423 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), ArgBeg, ArgEnd); 2424 2425 const CGFunctionInfo &FnInfo = CGM.getTypes().getFunctionInfo(Args, FnType); 2426 2427 // C99 6.5.2.2p6: 2428 // If the expression that denotes the called function has a type 2429 // that does not include a prototype, [the default argument 2430 // promotions are performed]. If the number of arguments does not 2431 // equal the number of parameters, the behavior is undefined. If 2432 // the function is defined with a type that includes a prototype, 2433 // and either the prototype ends with an ellipsis (, ...) or the 2434 // types of the arguments after promotion are not compatible with 2435 // the types of the parameters, the behavior is undefined. If the 2436 // function is defined with a type that does not include a 2437 // prototype, and the types of the arguments after promotion are 2438 // not compatible with those of the parameters after promotion, 2439 // the behavior is undefined [except in some trivial cases]. 2440 // That is, in the general case, we should assume that a call 2441 // through an unprototyped function type works like a *non-variadic* 2442 // call. The way we make this work is to cast to the exact type 2443 // of the promoted arguments. 2444 if (isa<FunctionNoProtoType>(FnType) && 2445 !getTargetHooks().isNoProtoCallVariadic(FnType->getCallConv())) { 2446 assert(cast<llvm::FunctionType>(Callee->getType()->getContainedType(0)) 2447 ->isVarArg()); 2448 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo, false); 2449 CalleeTy = CalleeTy->getPointerTo(); 2450 Callee = Builder.CreateBitCast(Callee, CalleeTy, "callee.knr.cast"); 2451 } 2452 2453 return EmitCall(FnInfo, Callee, ReturnValue, Args, TargetDecl); 2454 } 2455 2456 LValue CodeGenFunction:: 2457 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) { 2458 llvm::Value *BaseV; 2459 if (E->getOpcode() == BO_PtrMemI) 2460 BaseV = EmitScalarExpr(E->getLHS()); 2461 else 2462 BaseV = EmitLValue(E->getLHS()).getAddress(); 2463 2464 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS()); 2465 2466 const MemberPointerType *MPT 2467 = E->getRHS()->getType()->getAs<MemberPointerType>(); 2468 2469 llvm::Value *AddV = 2470 CGM.getCXXABI().EmitMemberDataPointerAddress(*this, BaseV, OffsetV, MPT); 2471 2472 return MakeAddrLValue(AddV, MPT->getPointeeType()); 2473 } 2474 2475 static void 2476 EmitAtomicOp(CodeGenFunction &CGF, AtomicExpr *E, llvm::Value *Dest, 2477 llvm::Value *Ptr, llvm::Value *Val1, llvm::Value *Val2, 2478 uint64_t Size, unsigned Align, llvm::AtomicOrdering Order) { 2479 if (E->isCmpXChg()) { 2480 // Note that cmpxchg only supports specifying one ordering and 2481 // doesn't support weak cmpxchg, at least at the moment. 2482 llvm::LoadInst *LoadVal1 = CGF.Builder.CreateLoad(Val1); 2483 LoadVal1->setAlignment(Align); 2484 llvm::LoadInst *LoadVal2 = CGF.Builder.CreateLoad(Val2); 2485 LoadVal2->setAlignment(Align); 2486 llvm::AtomicCmpXchgInst *CXI = 2487 CGF.Builder.CreateAtomicCmpXchg(Ptr, LoadVal1, LoadVal2, Order); 2488 CXI->setVolatile(E->isVolatile()); 2489 llvm::StoreInst *StoreVal1 = CGF.Builder.CreateStore(CXI, Val1); 2490 StoreVal1->setAlignment(Align); 2491 llvm::Value *Cmp = CGF.Builder.CreateICmpEQ(CXI, LoadVal1); 2492 CGF.EmitStoreOfScalar(Cmp, CGF.MakeAddrLValue(Dest, E->getType())); 2493 return; 2494 } 2495 2496 if (E->getOp() == AtomicExpr::Load) { 2497 llvm::LoadInst *Load = CGF.Builder.CreateLoad(Ptr); 2498 Load->setAtomic(Order); 2499 Load->setAlignment(Size); 2500 Load->setVolatile(E->isVolatile()); 2501 llvm::StoreInst *StoreDest = CGF.Builder.CreateStore(Load, Dest); 2502 StoreDest->setAlignment(Align); 2503 return; 2504 } 2505 2506 if (E->getOp() == AtomicExpr::Store) { 2507 assert(!Dest && "Store does not return a value"); 2508 llvm::LoadInst *LoadVal1 = CGF.Builder.CreateLoad(Val1); 2509 LoadVal1->setAlignment(Align); 2510 llvm::StoreInst *Store = CGF.Builder.CreateStore(LoadVal1, Ptr); 2511 Store->setAtomic(Order); 2512 Store->setAlignment(Size); 2513 Store->setVolatile(E->isVolatile()); 2514 return; 2515 } 2516 2517 llvm::AtomicRMWInst::BinOp Op = llvm::AtomicRMWInst::Add; 2518 switch (E->getOp()) { 2519 case AtomicExpr::CmpXchgWeak: 2520 case AtomicExpr::CmpXchgStrong: 2521 case AtomicExpr::Store: 2522 case AtomicExpr::Load: assert(0 && "Already handled!"); 2523 case AtomicExpr::Add: Op = llvm::AtomicRMWInst::Add; break; 2524 case AtomicExpr::Sub: Op = llvm::AtomicRMWInst::Sub; break; 2525 case AtomicExpr::And: Op = llvm::AtomicRMWInst::And; break; 2526 case AtomicExpr::Or: Op = llvm::AtomicRMWInst::Or; break; 2527 case AtomicExpr::Xor: Op = llvm::AtomicRMWInst::Xor; break; 2528 case AtomicExpr::Xchg: Op = llvm::AtomicRMWInst::Xchg; break; 2529 } 2530 llvm::LoadInst *LoadVal1 = CGF.Builder.CreateLoad(Val1); 2531 LoadVal1->setAlignment(Align); 2532 llvm::AtomicRMWInst *RMWI = 2533 CGF.Builder.CreateAtomicRMW(Op, Ptr, LoadVal1, Order); 2534 RMWI->setVolatile(E->isVolatile()); 2535 llvm::StoreInst *StoreDest = CGF.Builder.CreateStore(RMWI, Dest); 2536 StoreDest->setAlignment(Align); 2537 } 2538 2539 // This function emits any expression (scalar, complex, or aggregate) 2540 // into a temporary alloca. 2541 static llvm::Value * 2542 EmitValToTemp(CodeGenFunction &CGF, Expr *E) { 2543 llvm::Value *DeclPtr = CGF.CreateMemTemp(E->getType(), ".atomictmp"); 2544 CGF.EmitAnyExprToMem(E, DeclPtr, E->getType().getQualifiers(), 2545 /*Init*/ true); 2546 return DeclPtr; 2547 } 2548 2549 static RValue ConvertTempToRValue(CodeGenFunction &CGF, QualType Ty, 2550 llvm::Value *Dest) { 2551 if (Ty->isAnyComplexType()) 2552 return RValue::getComplex(CGF.LoadComplexFromAddr(Dest, false)); 2553 if (CGF.hasAggregateLLVMType(Ty)) 2554 return RValue::getAggregate(Dest); 2555 return RValue::get(CGF.EmitLoadOfScalar(CGF.MakeAddrLValue(Dest, Ty))); 2556 } 2557 2558 RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E, llvm::Value *Dest) { 2559 QualType AtomicTy = E->getPtr()->getType()->getPointeeType(); 2560 QualType MemTy = AtomicTy->getAs<AtomicType>()->getValueType(); 2561 CharUnits sizeChars = getContext().getTypeSizeInChars(AtomicTy); 2562 uint64_t Size = sizeChars.getQuantity(); 2563 CharUnits alignChars = getContext().getTypeAlignInChars(AtomicTy); 2564 unsigned Align = alignChars.getQuantity(); 2565 unsigned MaxInlineWidth = 2566 getContext().getTargetInfo().getMaxAtomicInlineWidth(); 2567 bool UseLibcall = (Size != Align || Size > MaxInlineWidth); 2568 2569 llvm::Value *Ptr, *Order, *OrderFail = 0, *Val1 = 0, *Val2 = 0; 2570 Ptr = EmitScalarExpr(E->getPtr()); 2571 Order = EmitScalarExpr(E->getOrder()); 2572 if (E->isCmpXChg()) { 2573 Val1 = EmitScalarExpr(E->getVal1()); 2574 Val2 = EmitValToTemp(*this, E->getVal2()); 2575 OrderFail = EmitScalarExpr(E->getOrderFail()); 2576 (void)OrderFail; // OrderFail is unused at the moment 2577 } else if ((E->getOp() == AtomicExpr::Add || E->getOp() == AtomicExpr::Sub) && 2578 MemTy->isPointerType()) { 2579 // For pointers, we're required to do a bit of math: adding 1 to an int* 2580 // is not the same as adding 1 to a uintptr_t. 2581 QualType Val1Ty = E->getVal1()->getType(); 2582 llvm::Value *Val1Scalar = EmitScalarExpr(E->getVal1()); 2583 CharUnits PointeeIncAmt = 2584 getContext().getTypeSizeInChars(MemTy->getPointeeType()); 2585 Val1Scalar = Builder.CreateMul(Val1Scalar, CGM.getSize(PointeeIncAmt)); 2586 Val1 = CreateMemTemp(Val1Ty, ".atomictmp"); 2587 EmitStoreOfScalar(Val1Scalar, MakeAddrLValue(Val1, Val1Ty)); 2588 } else if (E->getOp() != AtomicExpr::Load) { 2589 Val1 = EmitValToTemp(*this, E->getVal1()); 2590 } 2591 2592 if (E->getOp() != AtomicExpr::Store && !Dest) 2593 Dest = CreateMemTemp(E->getType(), ".atomicdst"); 2594 2595 if (UseLibcall) { 2596 // FIXME: Finalize what the libcalls are actually supposed to look like. 2597 // See also http://gcc.gnu.org/wiki/Atomic/GCCMM/LIbrary . 2598 return EmitUnsupportedRValue(E, "atomic library call"); 2599 } 2600 #if 0 2601 if (UseLibcall) { 2602 const char* LibCallName; 2603 switch (E->getOp()) { 2604 case AtomicExpr::CmpXchgWeak: 2605 LibCallName = "__atomic_compare_exchange_generic"; break; 2606 case AtomicExpr::CmpXchgStrong: 2607 LibCallName = "__atomic_compare_exchange_generic"; break; 2608 case AtomicExpr::Add: LibCallName = "__atomic_fetch_add_generic"; break; 2609 case AtomicExpr::Sub: LibCallName = "__atomic_fetch_sub_generic"; break; 2610 case AtomicExpr::And: LibCallName = "__atomic_fetch_and_generic"; break; 2611 case AtomicExpr::Or: LibCallName = "__atomic_fetch_or_generic"; break; 2612 case AtomicExpr::Xor: LibCallName = "__atomic_fetch_xor_generic"; break; 2613 case AtomicExpr::Xchg: LibCallName = "__atomic_exchange_generic"; break; 2614 case AtomicExpr::Store: LibCallName = "__atomic_store_generic"; break; 2615 case AtomicExpr::Load: LibCallName = "__atomic_load_generic"; break; 2616 } 2617 llvm::SmallVector<QualType, 4> Params; 2618 CallArgList Args; 2619 QualType RetTy = getContext().VoidTy; 2620 if (E->getOp() != AtomicExpr::Store && !E->isCmpXChg()) 2621 Args.add(RValue::get(EmitCastToVoidPtr(Dest)), 2622 getContext().VoidPtrTy); 2623 Args.add(RValue::get(EmitCastToVoidPtr(Ptr)), 2624 getContext().VoidPtrTy); 2625 if (E->getOp() != AtomicExpr::Load) 2626 Args.add(RValue::get(EmitCastToVoidPtr(Val1)), 2627 getContext().VoidPtrTy); 2628 if (E->isCmpXChg()) { 2629 Args.add(RValue::get(EmitCastToVoidPtr(Val2)), 2630 getContext().VoidPtrTy); 2631 RetTy = getContext().IntTy; 2632 } 2633 Args.add(RValue::get(llvm::ConstantInt::get(SizeTy, Size)), 2634 getContext().getSizeType()); 2635 const CGFunctionInfo &FuncInfo = 2636 CGM.getTypes().getFunctionInfo(RetTy, Args, FunctionType::ExtInfo()); 2637 llvm::FunctionType *FTy = CGM.getTypes().GetFunctionType(FuncInfo, false); 2638 llvm::Constant *Func = CGM.CreateRuntimeFunction(FTy, LibCallName); 2639 RValue Res = EmitCall(FuncInfo, Func, ReturnValueSlot(), Args); 2640 if (E->isCmpXChg()) 2641 return Res; 2642 if (E->getOp() == AtomicExpr::Store) 2643 return RValue::get(0); 2644 return ConvertTempToRValue(*this, E->getType(), Dest); 2645 } 2646 #endif 2647 llvm::Type *IPtrTy = 2648 llvm::IntegerType::get(getLLVMContext(), Size * 8)->getPointerTo(); 2649 llvm::Value *OrigDest = Dest; 2650 Ptr = Builder.CreateBitCast(Ptr, IPtrTy); 2651 if (Val1) Val1 = Builder.CreateBitCast(Val1, IPtrTy); 2652 if (Val2) Val2 = Builder.CreateBitCast(Val2, IPtrTy); 2653 if (Dest && !E->isCmpXChg()) Dest = Builder.CreateBitCast(Dest, IPtrTy); 2654 2655 if (isa<llvm::ConstantInt>(Order)) { 2656 int ord = cast<llvm::ConstantInt>(Order)->getZExtValue(); 2657 switch (ord) { 2658 case 0: // memory_order_relaxed 2659 EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, Size, Align, 2660 llvm::Monotonic); 2661 break; 2662 case 1: // memory_order_consume 2663 case 2: // memory_order_acquire 2664 EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, Size, Align, 2665 llvm::Acquire); 2666 break; 2667 case 3: // memory_order_release 2668 EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, Size, Align, 2669 llvm::Release); 2670 break; 2671 case 4: // memory_order_acq_rel 2672 EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, Size, Align, 2673 llvm::AcquireRelease); 2674 break; 2675 case 5: // memory_order_seq_cst 2676 EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, Size, Align, 2677 llvm::SequentiallyConsistent); 2678 break; 2679 default: // invalid order 2680 // We should not ever get here normally, but it's hard to 2681 // enforce that in general. 2682 break; 2683 } 2684 if (E->getOp() == AtomicExpr::Store) 2685 return RValue::get(0); 2686 return ConvertTempToRValue(*this, E->getType(), OrigDest); 2687 } 2688 2689 // Long case, when Order isn't obviously constant. 2690 2691 // Create all the relevant BB's 2692 llvm::BasicBlock *MonotonicBB = 0, *AcquireBB = 0, *ReleaseBB = 0, 2693 *AcqRelBB = 0, *SeqCstBB = 0; 2694 MonotonicBB = createBasicBlock("monotonic", CurFn); 2695 if (E->getOp() != AtomicExpr::Store) 2696 AcquireBB = createBasicBlock("acquire", CurFn); 2697 if (E->getOp() != AtomicExpr::Load) 2698 ReleaseBB = createBasicBlock("release", CurFn); 2699 if (E->getOp() != AtomicExpr::Load && E->getOp() != AtomicExpr::Store) 2700 AcqRelBB = createBasicBlock("acqrel", CurFn); 2701 SeqCstBB = createBasicBlock("seqcst", CurFn); 2702 llvm::BasicBlock *ContBB = createBasicBlock("atomic.continue", CurFn); 2703 2704 // Create the switch for the split 2705 // MonotonicBB is arbitrarily chosen as the default case; in practice, this 2706 // doesn't matter unless someone is crazy enough to use something that 2707 // doesn't fold to a constant for the ordering. 2708 Order = Builder.CreateIntCast(Order, Builder.getInt32Ty(), false); 2709 llvm::SwitchInst *SI = Builder.CreateSwitch(Order, MonotonicBB); 2710 2711 // Emit all the different atomics 2712 Builder.SetInsertPoint(MonotonicBB); 2713 EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, Size, Align, 2714 llvm::Monotonic); 2715 Builder.CreateBr(ContBB); 2716 if (E->getOp() != AtomicExpr::Store) { 2717 Builder.SetInsertPoint(AcquireBB); 2718 EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, Size, Align, 2719 llvm::Acquire); 2720 Builder.CreateBr(ContBB); 2721 SI->addCase(Builder.getInt32(1), AcquireBB); 2722 SI->addCase(Builder.getInt32(2), AcquireBB); 2723 } 2724 if (E->getOp() != AtomicExpr::Load) { 2725 Builder.SetInsertPoint(ReleaseBB); 2726 EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, Size, Align, 2727 llvm::Release); 2728 Builder.CreateBr(ContBB); 2729 SI->addCase(Builder.getInt32(3), ReleaseBB); 2730 } 2731 if (E->getOp() != AtomicExpr::Load && E->getOp() != AtomicExpr::Store) { 2732 Builder.SetInsertPoint(AcqRelBB); 2733 EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, Size, Align, 2734 llvm::AcquireRelease); 2735 Builder.CreateBr(ContBB); 2736 SI->addCase(Builder.getInt32(4), AcqRelBB); 2737 } 2738 Builder.SetInsertPoint(SeqCstBB); 2739 EmitAtomicOp(*this, E, Dest, Ptr, Val1, Val2, Size, Align, 2740 llvm::SequentiallyConsistent); 2741 Builder.CreateBr(ContBB); 2742 SI->addCase(Builder.getInt32(5), SeqCstBB); 2743 2744 // Cleanup and return 2745 Builder.SetInsertPoint(ContBB); 2746 if (E->getOp() == AtomicExpr::Store) 2747 return RValue::get(0); 2748 return ConvertTempToRValue(*this, E->getType(), OrigDest); 2749 } 2750 2751 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, unsigned AccuracyN, 2752 unsigned AccuracyD) { 2753 assert(Val->getType()->isFPOrFPVectorTy()); 2754 if (!AccuracyN || !isa<llvm::Instruction>(Val)) 2755 return; 2756 2757 llvm::Value *Vals[2]; 2758 Vals[0] = llvm::ConstantInt::get(Int32Ty, AccuracyN); 2759 Vals[1] = llvm::ConstantInt::get(Int32Ty, AccuracyD); 2760 llvm::MDNode *Node = llvm::MDNode::get(getLLVMContext(), Vals); 2761 2762 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpaccuracy, 2763 Node); 2764 } 2765 2766 namespace { 2767 struct LValueOrRValue { 2768 LValue LV; 2769 RValue RV; 2770 }; 2771 } 2772 2773 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF, 2774 const PseudoObjectExpr *E, 2775 bool forLValue, 2776 AggValueSlot slot) { 2777 llvm::SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques; 2778 2779 // Find the result expression, if any. 2780 const Expr *resultExpr = E->getResultExpr(); 2781 LValueOrRValue result; 2782 2783 for (PseudoObjectExpr::const_semantics_iterator 2784 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) { 2785 const Expr *semantic = *i; 2786 2787 // If this semantic expression is an opaque value, bind it 2788 // to the result of its source expression. 2789 if (const OpaqueValueExpr *ov = dyn_cast<OpaqueValueExpr>(semantic)) { 2790 2791 // If this is the result expression, we may need to evaluate 2792 // directly into the slot. 2793 typedef CodeGenFunction::OpaqueValueMappingData OVMA; 2794 OVMA opaqueData; 2795 if (ov == resultExpr && ov->isRValue() && !forLValue && 2796 CodeGenFunction::hasAggregateLLVMType(ov->getType()) && 2797 !ov->getType()->isAnyComplexType()) { 2798 CGF.EmitAggExpr(ov->getSourceExpr(), slot); 2799 2800 LValue LV = CGF.MakeAddrLValue(slot.getAddr(), ov->getType()); 2801 opaqueData = OVMA::bind(CGF, ov, LV); 2802 result.RV = slot.asRValue(); 2803 2804 // Otherwise, emit as normal. 2805 } else { 2806 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr()); 2807 2808 // If this is the result, also evaluate the result now. 2809 if (ov == resultExpr) { 2810 if (forLValue) 2811 result.LV = CGF.EmitLValue(ov); 2812 else 2813 result.RV = CGF.EmitAnyExpr(ov, slot); 2814 } 2815 } 2816 2817 opaques.push_back(opaqueData); 2818 2819 // Otherwise, if the expression is the result, evaluate it 2820 // and remember the result. 2821 } else if (semantic == resultExpr) { 2822 if (forLValue) 2823 result.LV = CGF.EmitLValue(semantic); 2824 else 2825 result.RV = CGF.EmitAnyExpr(semantic, slot); 2826 2827 // Otherwise, evaluate the expression in an ignored context. 2828 } else { 2829 CGF.EmitIgnoredExpr(semantic); 2830 } 2831 } 2832 2833 // Unbind all the opaques now. 2834 for (unsigned i = 0, e = opaques.size(); i != e; ++i) 2835 opaques[i].unbind(CGF); 2836 2837 return result; 2838 } 2839 2840 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E, 2841 AggValueSlot slot) { 2842 return emitPseudoObjectExpr(*this, E, false, slot).RV; 2843 } 2844 2845 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) { 2846 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV; 2847 } 2848