1 //===--- CGExpr.cpp - Emit LLVM Code from Expressions ---------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This contains code to emit Expr nodes as LLVM code. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "CGCUDARuntime.h" 14 #include "CGCXXABI.h" 15 #include "CGCall.h" 16 #include "CGCleanup.h" 17 #include "CGDebugInfo.h" 18 #include "CGObjCRuntime.h" 19 #include "CGOpenMPRuntime.h" 20 #include "CGRecordLayout.h" 21 #include "CodeGenFunction.h" 22 #include "CodeGenModule.h" 23 #include "ConstantEmitter.h" 24 #include "TargetInfo.h" 25 #include "clang/AST/ASTContext.h" 26 #include "clang/AST/Attr.h" 27 #include "clang/AST/DeclObjC.h" 28 #include "clang/AST/NSAPI.h" 29 #include "clang/Basic/Builtins.h" 30 #include "clang/Basic/CodeGenOptions.h" 31 #include "clang/Basic/SourceManager.h" 32 #include "llvm/ADT/Hashing.h" 33 #include "llvm/ADT/StringExtras.h" 34 #include "llvm/IR/DataLayout.h" 35 #include "llvm/IR/Intrinsics.h" 36 #include "llvm/IR/IntrinsicsWebAssembly.h" 37 #include "llvm/IR/LLVMContext.h" 38 #include "llvm/IR/MDBuilder.h" 39 #include "llvm/IR/MatrixBuilder.h" 40 #include "llvm/Passes/OptimizationLevel.h" 41 #include "llvm/Support/ConvertUTF.h" 42 #include "llvm/Support/MathExtras.h" 43 #include "llvm/Support/Path.h" 44 #include "llvm/Support/SaveAndRestore.h" 45 #include "llvm/Support/xxhash.h" 46 #include "llvm/Transforms/Utils/SanitizerStats.h" 47 48 #include <optional> 49 #include <string> 50 51 using namespace clang; 52 using namespace CodeGen; 53 54 // Experiment to make sanitizers easier to debug 55 static llvm::cl::opt<bool> ClSanitizeDebugDeoptimization( 56 "ubsan-unique-traps", llvm::cl::Optional, 57 llvm::cl::desc("Deoptimize traps for UBSAN so there is 1 trap per check"), 58 llvm::cl::init(false)); 59 60 //===--------------------------------------------------------------------===// 61 // Miscellaneous Helper Methods 62 //===--------------------------------------------------------------------===// 63 64 /// CreateTempAlloca - This creates a alloca and inserts it into the entry 65 /// block. 66 Address CodeGenFunction::CreateTempAllocaWithoutCast(llvm::Type *Ty, 67 CharUnits Align, 68 const Twine &Name, 69 llvm::Value *ArraySize) { 70 auto Alloca = CreateTempAlloca(Ty, Name, ArraySize); 71 Alloca->setAlignment(Align.getAsAlign()); 72 return Address(Alloca, Ty, Align, KnownNonNull); 73 } 74 75 /// CreateTempAlloca - This creates a alloca and inserts it into the entry 76 /// block. The alloca is casted to default address space if necessary. 77 Address CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, CharUnits Align, 78 const Twine &Name, 79 llvm::Value *ArraySize, 80 Address *AllocaAddr) { 81 auto Alloca = CreateTempAllocaWithoutCast(Ty, Align, Name, ArraySize); 82 if (AllocaAddr) 83 *AllocaAddr = Alloca; 84 llvm::Value *V = Alloca.getPointer(); 85 // Alloca always returns a pointer in alloca address space, which may 86 // be different from the type defined by the language. For example, 87 // in C++ the auto variables are in the default address space. Therefore 88 // cast alloca to the default address space when necessary. 89 if (getASTAllocaAddressSpace() != LangAS::Default) { 90 auto DestAddrSpace = getContext().getTargetAddressSpace(LangAS::Default); 91 llvm::IRBuilderBase::InsertPointGuard IPG(Builder); 92 // When ArraySize is nullptr, alloca is inserted at AllocaInsertPt, 93 // otherwise alloca is inserted at the current insertion point of the 94 // builder. 95 if (!ArraySize) 96 Builder.SetInsertPoint(getPostAllocaInsertPoint()); 97 V = getTargetHooks().performAddrSpaceCast( 98 *this, V, getASTAllocaAddressSpace(), LangAS::Default, 99 Ty->getPointerTo(DestAddrSpace), /*non-null*/ true); 100 } 101 102 return Address(V, Ty, Align, KnownNonNull); 103 } 104 105 /// CreateTempAlloca - This creates an alloca and inserts it into the entry 106 /// block if \p ArraySize is nullptr, otherwise inserts it at the current 107 /// insertion point of the builder. 108 llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, 109 const Twine &Name, 110 llvm::Value *ArraySize) { 111 if (ArraySize) 112 return Builder.CreateAlloca(Ty, ArraySize, Name); 113 return new llvm::AllocaInst(Ty, CGM.getDataLayout().getAllocaAddrSpace(), 114 ArraySize, Name, AllocaInsertPt); 115 } 116 117 /// CreateDefaultAlignTempAlloca - This creates an alloca with the 118 /// default alignment of the corresponding LLVM type, which is *not* 119 /// guaranteed to be related in any way to the expected alignment of 120 /// an AST type that might have been lowered to Ty. 121 Address CodeGenFunction::CreateDefaultAlignTempAlloca(llvm::Type *Ty, 122 const Twine &Name) { 123 CharUnits Align = 124 CharUnits::fromQuantity(CGM.getDataLayout().getPrefTypeAlign(Ty)); 125 return CreateTempAlloca(Ty, Align, Name); 126 } 127 128 Address CodeGenFunction::CreateIRTemp(QualType Ty, const Twine &Name) { 129 CharUnits Align = getContext().getTypeAlignInChars(Ty); 130 return CreateTempAlloca(ConvertType(Ty), Align, Name); 131 } 132 133 Address CodeGenFunction::CreateMemTemp(QualType Ty, const Twine &Name, 134 Address *Alloca) { 135 // FIXME: Should we prefer the preferred type alignment here? 136 return CreateMemTemp(Ty, getContext().getTypeAlignInChars(Ty), Name, Alloca); 137 } 138 139 Address CodeGenFunction::CreateMemTemp(QualType Ty, CharUnits Align, 140 const Twine &Name, Address *Alloca) { 141 Address Result = CreateTempAlloca(ConvertTypeForMem(Ty), Align, Name, 142 /*ArraySize=*/nullptr, Alloca); 143 144 if (Ty->isConstantMatrixType()) { 145 auto *ArrayTy = cast<llvm::ArrayType>(Result.getElementType()); 146 auto *VectorTy = llvm::FixedVectorType::get(ArrayTy->getElementType(), 147 ArrayTy->getNumElements()); 148 149 Result = Address(Result.getPointer(), VectorTy, Result.getAlignment(), 150 KnownNonNull); 151 } 152 return Result; 153 } 154 155 Address CodeGenFunction::CreateMemTempWithoutCast(QualType Ty, CharUnits Align, 156 const Twine &Name) { 157 return CreateTempAllocaWithoutCast(ConvertTypeForMem(Ty), Align, Name); 158 } 159 160 Address CodeGenFunction::CreateMemTempWithoutCast(QualType Ty, 161 const Twine &Name) { 162 return CreateMemTempWithoutCast(Ty, getContext().getTypeAlignInChars(Ty), 163 Name); 164 } 165 166 /// EvaluateExprAsBool - Perform the usual unary conversions on the specified 167 /// expression and compare the result against zero, returning an Int1Ty value. 168 llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) { 169 PGO.setCurrentStmt(E); 170 if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) { 171 llvm::Value *MemPtr = EmitScalarExpr(E); 172 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT); 173 } 174 175 QualType BoolTy = getContext().BoolTy; 176 SourceLocation Loc = E->getExprLoc(); 177 CGFPOptionsRAII FPOptsRAII(*this, E); 178 if (!E->getType()->isAnyComplexType()) 179 return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy, Loc); 180 181 return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(), BoolTy, 182 Loc); 183 } 184 185 /// EmitIgnoredExpr - Emit code to compute the specified expression, 186 /// ignoring the result. 187 void CodeGenFunction::EmitIgnoredExpr(const Expr *E) { 188 if (E->isPRValue()) 189 return (void)EmitAnyExpr(E, AggValueSlot::ignored(), true); 190 191 // if this is a bitfield-resulting conditional operator, we can special case 192 // emit this. The normal 'EmitLValue' version of this is particularly 193 // difficult to codegen for, since creating a single "LValue" for two 194 // different sized arguments here is not particularly doable. 195 if (const auto *CondOp = dyn_cast<AbstractConditionalOperator>( 196 E->IgnoreParenNoopCasts(getContext()))) { 197 if (CondOp->getObjectKind() == OK_BitField) 198 return EmitIgnoredConditionalOperator(CondOp); 199 } 200 201 // Just emit it as an l-value and drop the result. 202 EmitLValue(E); 203 } 204 205 /// EmitAnyExpr - Emit code to compute the specified expression which 206 /// can have any type. The result is returned as an RValue struct. 207 /// If this is an aggregate expression, AggSlot indicates where the 208 /// result should be returned. 209 RValue CodeGenFunction::EmitAnyExpr(const Expr *E, 210 AggValueSlot aggSlot, 211 bool ignoreResult) { 212 switch (getEvaluationKind(E->getType())) { 213 case TEK_Scalar: 214 return RValue::get(EmitScalarExpr(E, ignoreResult)); 215 case TEK_Complex: 216 return RValue::getComplex(EmitComplexExpr(E, ignoreResult, ignoreResult)); 217 case TEK_Aggregate: 218 if (!ignoreResult && aggSlot.isIgnored()) 219 aggSlot = CreateAggTemp(E->getType(), "agg-temp"); 220 EmitAggExpr(E, aggSlot); 221 return aggSlot.asRValue(); 222 } 223 llvm_unreachable("bad evaluation kind"); 224 } 225 226 /// EmitAnyExprToTemp - Similar to EmitAnyExpr(), however, the result will 227 /// always be accessible even if no aggregate location is provided. 228 RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) { 229 AggValueSlot AggSlot = AggValueSlot::ignored(); 230 231 if (hasAggregateEvaluationKind(E->getType())) 232 AggSlot = CreateAggTemp(E->getType(), "agg.tmp"); 233 return EmitAnyExpr(E, AggSlot); 234 } 235 236 /// EmitAnyExprToMem - Evaluate an expression into a given memory 237 /// location. 238 void CodeGenFunction::EmitAnyExprToMem(const Expr *E, 239 Address Location, 240 Qualifiers Quals, 241 bool IsInit) { 242 // FIXME: This function should take an LValue as an argument. 243 switch (getEvaluationKind(E->getType())) { 244 case TEK_Complex: 245 EmitComplexExprIntoLValue(E, MakeAddrLValue(Location, E->getType()), 246 /*isInit*/ false); 247 return; 248 249 case TEK_Aggregate: { 250 EmitAggExpr(E, AggValueSlot::forAddr(Location, Quals, 251 AggValueSlot::IsDestructed_t(IsInit), 252 AggValueSlot::DoesNotNeedGCBarriers, 253 AggValueSlot::IsAliased_t(!IsInit), 254 AggValueSlot::MayOverlap)); 255 return; 256 } 257 258 case TEK_Scalar: { 259 RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false)); 260 LValue LV = MakeAddrLValue(Location, E->getType()); 261 EmitStoreThroughLValue(RV, LV); 262 return; 263 } 264 } 265 llvm_unreachable("bad evaluation kind"); 266 } 267 268 static void 269 pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M, 270 const Expr *E, Address ReferenceTemporary) { 271 // Objective-C++ ARC: 272 // If we are binding a reference to a temporary that has ownership, we 273 // need to perform retain/release operations on the temporary. 274 // 275 // FIXME: This should be looking at E, not M. 276 if (auto Lifetime = M->getType().getObjCLifetime()) { 277 switch (Lifetime) { 278 case Qualifiers::OCL_None: 279 case Qualifiers::OCL_ExplicitNone: 280 // Carry on to normal cleanup handling. 281 break; 282 283 case Qualifiers::OCL_Autoreleasing: 284 // Nothing to do; cleaned up by an autorelease pool. 285 return; 286 287 case Qualifiers::OCL_Strong: 288 case Qualifiers::OCL_Weak: 289 switch (StorageDuration Duration = M->getStorageDuration()) { 290 case SD_Static: 291 // Note: we intentionally do not register a cleanup to release 292 // the object on program termination. 293 return; 294 295 case SD_Thread: 296 // FIXME: We should probably register a cleanup in this case. 297 return; 298 299 case SD_Automatic: 300 case SD_FullExpression: 301 CodeGenFunction::Destroyer *Destroy; 302 CleanupKind CleanupKind; 303 if (Lifetime == Qualifiers::OCL_Strong) { 304 const ValueDecl *VD = M->getExtendingDecl(); 305 bool Precise = 306 VD && isa<VarDecl>(VD) && VD->hasAttr<ObjCPreciseLifetimeAttr>(); 307 CleanupKind = CGF.getARCCleanupKind(); 308 Destroy = Precise ? &CodeGenFunction::destroyARCStrongPrecise 309 : &CodeGenFunction::destroyARCStrongImprecise; 310 } else { 311 // __weak objects always get EH cleanups; otherwise, exceptions 312 // could cause really nasty crashes instead of mere leaks. 313 CleanupKind = NormalAndEHCleanup; 314 Destroy = &CodeGenFunction::destroyARCWeak; 315 } 316 if (Duration == SD_FullExpression) 317 CGF.pushDestroy(CleanupKind, ReferenceTemporary, 318 M->getType(), *Destroy, 319 CleanupKind & EHCleanup); 320 else 321 CGF.pushLifetimeExtendedDestroy(CleanupKind, ReferenceTemporary, 322 M->getType(), 323 *Destroy, CleanupKind & EHCleanup); 324 return; 325 326 case SD_Dynamic: 327 llvm_unreachable("temporary cannot have dynamic storage duration"); 328 } 329 llvm_unreachable("unknown storage duration"); 330 } 331 } 332 333 CXXDestructorDecl *ReferenceTemporaryDtor = nullptr; 334 if (const RecordType *RT = 335 E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) { 336 // Get the destructor for the reference temporary. 337 auto *ClassDecl = cast<CXXRecordDecl>(RT->getDecl()); 338 if (!ClassDecl->hasTrivialDestructor()) 339 ReferenceTemporaryDtor = ClassDecl->getDestructor(); 340 } 341 342 if (!ReferenceTemporaryDtor) 343 return; 344 345 // Call the destructor for the temporary. 346 switch (M->getStorageDuration()) { 347 case SD_Static: 348 case SD_Thread: { 349 llvm::FunctionCallee CleanupFn; 350 llvm::Constant *CleanupArg; 351 if (E->getType()->isArrayType()) { 352 CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper( 353 ReferenceTemporary, E->getType(), 354 CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions, 355 dyn_cast_or_null<VarDecl>(M->getExtendingDecl())); 356 CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy); 357 } else { 358 CleanupFn = CGF.CGM.getAddrAndTypeOfCXXStructor( 359 GlobalDecl(ReferenceTemporaryDtor, Dtor_Complete)); 360 CleanupArg = cast<llvm::Constant>(ReferenceTemporary.getPointer()); 361 } 362 CGF.CGM.getCXXABI().registerGlobalDtor( 363 CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg); 364 break; 365 } 366 367 case SD_FullExpression: 368 CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(), 369 CodeGenFunction::destroyCXXObject, 370 CGF.getLangOpts().Exceptions); 371 break; 372 373 case SD_Automatic: 374 CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup, 375 ReferenceTemporary, E->getType(), 376 CodeGenFunction::destroyCXXObject, 377 CGF.getLangOpts().Exceptions); 378 break; 379 380 case SD_Dynamic: 381 llvm_unreachable("temporary cannot have dynamic storage duration"); 382 } 383 } 384 385 static Address createReferenceTemporary(CodeGenFunction &CGF, 386 const MaterializeTemporaryExpr *M, 387 const Expr *Inner, 388 Address *Alloca = nullptr) { 389 auto &TCG = CGF.getTargetHooks(); 390 switch (M->getStorageDuration()) { 391 case SD_FullExpression: 392 case SD_Automatic: { 393 // If we have a constant temporary array or record try to promote it into a 394 // constant global under the same rules a normal constant would've been 395 // promoted. This is easier on the optimizer and generally emits fewer 396 // instructions. 397 QualType Ty = Inner->getType(); 398 if (CGF.CGM.getCodeGenOpts().MergeAllConstants && 399 (Ty->isArrayType() || Ty->isRecordType()) && 400 Ty.isConstantStorage(CGF.getContext(), true, false)) 401 if (auto Init = ConstantEmitter(CGF).tryEmitAbstract(Inner, Ty)) { 402 auto AS = CGF.CGM.GetGlobalConstantAddressSpace(); 403 auto *GV = new llvm::GlobalVariable( 404 CGF.CGM.getModule(), Init->getType(), /*isConstant=*/true, 405 llvm::GlobalValue::PrivateLinkage, Init, ".ref.tmp", nullptr, 406 llvm::GlobalValue::NotThreadLocal, 407 CGF.getContext().getTargetAddressSpace(AS)); 408 CharUnits alignment = CGF.getContext().getTypeAlignInChars(Ty); 409 GV->setAlignment(alignment.getAsAlign()); 410 llvm::Constant *C = GV; 411 if (AS != LangAS::Default) 412 C = TCG.performAddrSpaceCast( 413 CGF.CGM, GV, AS, LangAS::Default, 414 GV->getValueType()->getPointerTo( 415 CGF.getContext().getTargetAddressSpace(LangAS::Default))); 416 // FIXME: Should we put the new global into a COMDAT? 417 return Address(C, GV->getValueType(), alignment); 418 } 419 return CGF.CreateMemTemp(Ty, "ref.tmp", Alloca); 420 } 421 case SD_Thread: 422 case SD_Static: 423 return CGF.CGM.GetAddrOfGlobalTemporary(M, Inner); 424 425 case SD_Dynamic: 426 llvm_unreachable("temporary can't have dynamic storage duration"); 427 } 428 llvm_unreachable("unknown storage duration"); 429 } 430 431 /// Helper method to check if the underlying ABI is AAPCS 432 static bool isAAPCS(const TargetInfo &TargetInfo) { 433 return TargetInfo.getABI().starts_with("aapcs"); 434 } 435 436 LValue CodeGenFunction:: 437 EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) { 438 const Expr *E = M->getSubExpr(); 439 440 assert((!M->getExtendingDecl() || !isa<VarDecl>(M->getExtendingDecl()) || 441 !cast<VarDecl>(M->getExtendingDecl())->isARCPseudoStrong()) && 442 "Reference should never be pseudo-strong!"); 443 444 // FIXME: ideally this would use EmitAnyExprToMem, however, we cannot do so 445 // as that will cause the lifetime adjustment to be lost for ARC 446 auto ownership = M->getType().getObjCLifetime(); 447 if (ownership != Qualifiers::OCL_None && 448 ownership != Qualifiers::OCL_ExplicitNone) { 449 Address Object = createReferenceTemporary(*this, M, E); 450 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) { 451 llvm::Type *Ty = ConvertTypeForMem(E->getType()); 452 Object = Object.withElementType(Ty); 453 454 // createReferenceTemporary will promote the temporary to a global with a 455 // constant initializer if it can. It can only do this to a value of 456 // ARC-manageable type if the value is global and therefore "immune" to 457 // ref-counting operations. Therefore we have no need to emit either a 458 // dynamic initialization or a cleanup and we can just return the address 459 // of the temporary. 460 if (Var->hasInitializer()) 461 return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl); 462 463 Var->setInitializer(CGM.EmitNullConstant(E->getType())); 464 } 465 LValue RefTempDst = MakeAddrLValue(Object, M->getType(), 466 AlignmentSource::Decl); 467 468 switch (getEvaluationKind(E->getType())) { 469 default: llvm_unreachable("expected scalar or aggregate expression"); 470 case TEK_Scalar: 471 EmitScalarInit(E, M->getExtendingDecl(), RefTempDst, false); 472 break; 473 case TEK_Aggregate: { 474 EmitAggExpr(E, AggValueSlot::forAddr(Object, 475 E->getType().getQualifiers(), 476 AggValueSlot::IsDestructed, 477 AggValueSlot::DoesNotNeedGCBarriers, 478 AggValueSlot::IsNotAliased, 479 AggValueSlot::DoesNotOverlap)); 480 break; 481 } 482 } 483 484 pushTemporaryCleanup(*this, M, E, Object); 485 return RefTempDst; 486 } 487 488 SmallVector<const Expr *, 2> CommaLHSs; 489 SmallVector<SubobjectAdjustment, 2> Adjustments; 490 E = E->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); 491 492 for (const auto &Ignored : CommaLHSs) 493 EmitIgnoredExpr(Ignored); 494 495 if (const auto *opaque = dyn_cast<OpaqueValueExpr>(E)) { 496 if (opaque->getType()->isRecordType()) { 497 assert(Adjustments.empty()); 498 return EmitOpaqueValueLValue(opaque); 499 } 500 } 501 502 // Create and initialize the reference temporary. 503 Address Alloca = Address::invalid(); 504 Address Object = createReferenceTemporary(*this, M, E, &Alloca); 505 if (auto *Var = dyn_cast<llvm::GlobalVariable>( 506 Object.getPointer()->stripPointerCasts())) { 507 llvm::Type *TemporaryType = ConvertTypeForMem(E->getType()); 508 Object = Object.withElementType(TemporaryType); 509 // If the temporary is a global and has a constant initializer or is a 510 // constant temporary that we promoted to a global, we may have already 511 // initialized it. 512 if (!Var->hasInitializer()) { 513 Var->setInitializer(CGM.EmitNullConstant(E->getType())); 514 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true); 515 } 516 } else { 517 switch (M->getStorageDuration()) { 518 case SD_Automatic: 519 if (auto *Size = EmitLifetimeStart( 520 CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()), 521 Alloca.getPointer())) { 522 pushCleanupAfterFullExpr<CallLifetimeEnd>(NormalEHLifetimeMarker, 523 Alloca, Size); 524 } 525 break; 526 527 case SD_FullExpression: { 528 if (!ShouldEmitLifetimeMarkers) 529 break; 530 531 // Avoid creating a conditional cleanup just to hold an llvm.lifetime.end 532 // marker. Instead, start the lifetime of a conditional temporary earlier 533 // so that it's unconditional. Don't do this with sanitizers which need 534 // more precise lifetime marks. However when inside an "await.suspend" 535 // block, we should always avoid conditional cleanup because it creates 536 // boolean marker that lives across await_suspend, which can destroy coro 537 // frame. 538 ConditionalEvaluation *OldConditional = nullptr; 539 CGBuilderTy::InsertPoint OldIP; 540 if (isInConditionalBranch() && !E->getType().isDestructedType() && 541 ((!SanOpts.has(SanitizerKind::HWAddress) && 542 !SanOpts.has(SanitizerKind::Memory) && 543 !CGM.getCodeGenOpts().SanitizeAddressUseAfterScope) || 544 inSuspendBlock())) { 545 OldConditional = OutermostConditional; 546 OutermostConditional = nullptr; 547 548 OldIP = Builder.saveIP(); 549 llvm::BasicBlock *Block = OldConditional->getStartingBlock(); 550 Builder.restoreIP(CGBuilderTy::InsertPoint( 551 Block, llvm::BasicBlock::iterator(Block->back()))); 552 } 553 554 if (auto *Size = EmitLifetimeStart( 555 CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()), 556 Alloca.getPointer())) { 557 pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Alloca, 558 Size); 559 } 560 561 if (OldConditional) { 562 OutermostConditional = OldConditional; 563 Builder.restoreIP(OldIP); 564 } 565 break; 566 } 567 568 default: 569 break; 570 } 571 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true); 572 } 573 pushTemporaryCleanup(*this, M, E, Object); 574 575 // Perform derived-to-base casts and/or field accesses, to get from the 576 // temporary object we created (and, potentially, for which we extended 577 // the lifetime) to the subobject we're binding the reference to. 578 for (SubobjectAdjustment &Adjustment : llvm::reverse(Adjustments)) { 579 switch (Adjustment.Kind) { 580 case SubobjectAdjustment::DerivedToBaseAdjustment: 581 Object = 582 GetAddressOfBaseClass(Object, Adjustment.DerivedToBase.DerivedClass, 583 Adjustment.DerivedToBase.BasePath->path_begin(), 584 Adjustment.DerivedToBase.BasePath->path_end(), 585 /*NullCheckValue=*/ false, E->getExprLoc()); 586 break; 587 588 case SubobjectAdjustment::FieldAdjustment: { 589 LValue LV = MakeAddrLValue(Object, E->getType(), AlignmentSource::Decl); 590 LV = EmitLValueForField(LV, Adjustment.Field); 591 assert(LV.isSimple() && 592 "materialized temporary field is not a simple lvalue"); 593 Object = LV.getAddress(*this); 594 break; 595 } 596 597 case SubobjectAdjustment::MemberPointerAdjustment: { 598 llvm::Value *Ptr = EmitScalarExpr(Adjustment.Ptr.RHS); 599 Object = EmitCXXMemberDataPointerAddress(E, Object, Ptr, 600 Adjustment.Ptr.MPT); 601 break; 602 } 603 } 604 } 605 606 return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl); 607 } 608 609 RValue 610 CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E) { 611 // Emit the expression as an lvalue. 612 LValue LV = EmitLValue(E); 613 assert(LV.isSimple()); 614 llvm::Value *Value = LV.getPointer(*this); 615 616 if (sanitizePerformTypeCheck() && !E->getType()->isFunctionType()) { 617 // C++11 [dcl.ref]p5 (as amended by core issue 453): 618 // If a glvalue to which a reference is directly bound designates neither 619 // an existing object or function of an appropriate type nor a region of 620 // storage of suitable size and alignment to contain an object of the 621 // reference's type, the behavior is undefined. 622 QualType Ty = E->getType(); 623 EmitTypeCheck(TCK_ReferenceBinding, E->getExprLoc(), Value, Ty); 624 } 625 626 return RValue::get(Value); 627 } 628 629 630 /// getAccessedFieldNo - Given an encoded value and a result number, return the 631 /// input field number being accessed. 632 unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx, 633 const llvm::Constant *Elts) { 634 return cast<llvm::ConstantInt>(Elts->getAggregateElement(Idx)) 635 ->getZExtValue(); 636 } 637 638 /// Emit the hash_16_bytes function from include/llvm/ADT/Hashing.h. 639 static llvm::Value *emitHash16Bytes(CGBuilderTy &Builder, llvm::Value *Low, 640 llvm::Value *High) { 641 llvm::Value *KMul = Builder.getInt64(0x9ddfea08eb382d69ULL); 642 llvm::Value *K47 = Builder.getInt64(47); 643 llvm::Value *A0 = Builder.CreateMul(Builder.CreateXor(Low, High), KMul); 644 llvm::Value *A1 = Builder.CreateXor(Builder.CreateLShr(A0, K47), A0); 645 llvm::Value *B0 = Builder.CreateMul(Builder.CreateXor(High, A1), KMul); 646 llvm::Value *B1 = Builder.CreateXor(Builder.CreateLShr(B0, K47), B0); 647 return Builder.CreateMul(B1, KMul); 648 } 649 650 bool CodeGenFunction::isNullPointerAllowed(TypeCheckKind TCK) { 651 return TCK == TCK_DowncastPointer || TCK == TCK_Upcast || 652 TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation; 653 } 654 655 bool CodeGenFunction::isVptrCheckRequired(TypeCheckKind TCK, QualType Ty) { 656 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl(); 657 return (RD && RD->hasDefinition() && RD->isDynamicClass()) && 658 (TCK == TCK_MemberAccess || TCK == TCK_MemberCall || 659 TCK == TCK_DowncastPointer || TCK == TCK_DowncastReference || 660 TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation); 661 } 662 663 bool CodeGenFunction::sanitizePerformTypeCheck() const { 664 return SanOpts.has(SanitizerKind::Null) || 665 SanOpts.has(SanitizerKind::Alignment) || 666 SanOpts.has(SanitizerKind::ObjectSize) || 667 SanOpts.has(SanitizerKind::Vptr); 668 } 669 670 void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc, 671 llvm::Value *Ptr, QualType Ty, 672 CharUnits Alignment, 673 SanitizerSet SkippedChecks, 674 llvm::Value *ArraySize) { 675 if (!sanitizePerformTypeCheck()) 676 return; 677 678 // Don't check pointers outside the default address space. The null check 679 // isn't correct, the object-size check isn't supported by LLVM, and we can't 680 // communicate the addresses to the runtime handler for the vptr check. 681 if (Ptr->getType()->getPointerAddressSpace()) 682 return; 683 684 // Don't check pointers to volatile data. The behavior here is implementation- 685 // defined. 686 if (Ty.isVolatileQualified()) 687 return; 688 689 SanitizerScope SanScope(this); 690 691 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 3> Checks; 692 llvm::BasicBlock *Done = nullptr; 693 694 // Quickly determine whether we have a pointer to an alloca. It's possible 695 // to skip null checks, and some alignment checks, for these pointers. This 696 // can reduce compile-time significantly. 697 auto PtrToAlloca = dyn_cast<llvm::AllocaInst>(Ptr->stripPointerCasts()); 698 699 llvm::Value *True = llvm::ConstantInt::getTrue(getLLVMContext()); 700 llvm::Value *IsNonNull = nullptr; 701 bool IsGuaranteedNonNull = 702 SkippedChecks.has(SanitizerKind::Null) || PtrToAlloca; 703 bool AllowNullPointers = isNullPointerAllowed(TCK); 704 if ((SanOpts.has(SanitizerKind::Null) || AllowNullPointers) && 705 !IsGuaranteedNonNull) { 706 // The glvalue must not be an empty glvalue. 707 IsNonNull = Builder.CreateIsNotNull(Ptr); 708 709 // The IR builder can constant-fold the null check if the pointer points to 710 // a constant. 711 IsGuaranteedNonNull = IsNonNull == True; 712 713 // Skip the null check if the pointer is known to be non-null. 714 if (!IsGuaranteedNonNull) { 715 if (AllowNullPointers) { 716 // When performing pointer casts, it's OK if the value is null. 717 // Skip the remaining checks in that case. 718 Done = createBasicBlock("null"); 719 llvm::BasicBlock *Rest = createBasicBlock("not.null"); 720 Builder.CreateCondBr(IsNonNull, Rest, Done); 721 EmitBlock(Rest); 722 } else { 723 Checks.push_back(std::make_pair(IsNonNull, SanitizerKind::Null)); 724 } 725 } 726 } 727 728 if (SanOpts.has(SanitizerKind::ObjectSize) && 729 !SkippedChecks.has(SanitizerKind::ObjectSize) && 730 !Ty->isIncompleteType()) { 731 uint64_t TySize = CGM.getMinimumObjectSize(Ty).getQuantity(); 732 llvm::Value *Size = llvm::ConstantInt::get(IntPtrTy, TySize); 733 if (ArraySize) 734 Size = Builder.CreateMul(Size, ArraySize); 735 736 // Degenerate case: new X[0] does not need an objectsize check. 737 llvm::Constant *ConstantSize = dyn_cast<llvm::Constant>(Size); 738 if (!ConstantSize || !ConstantSize->isNullValue()) { 739 // The glvalue must refer to a large enough storage region. 740 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation 741 // to check this. 742 // FIXME: Get object address space 743 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy }; 744 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys); 745 llvm::Value *Min = Builder.getFalse(); 746 llvm::Value *NullIsUnknown = Builder.getFalse(); 747 llvm::Value *Dynamic = Builder.getFalse(); 748 llvm::Value *LargeEnough = Builder.CreateICmpUGE( 749 Builder.CreateCall(F, {Ptr, Min, NullIsUnknown, Dynamic}), Size); 750 Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize)); 751 } 752 } 753 754 llvm::MaybeAlign AlignVal; 755 llvm::Value *PtrAsInt = nullptr; 756 757 if (SanOpts.has(SanitizerKind::Alignment) && 758 !SkippedChecks.has(SanitizerKind::Alignment)) { 759 AlignVal = Alignment.getAsMaybeAlign(); 760 if (!Ty->isIncompleteType() && !AlignVal) 761 AlignVal = CGM.getNaturalTypeAlignment(Ty, nullptr, nullptr, 762 /*ForPointeeType=*/true) 763 .getAsMaybeAlign(); 764 765 // The glvalue must be suitably aligned. 766 if (AlignVal && *AlignVal > llvm::Align(1) && 767 (!PtrToAlloca || PtrToAlloca->getAlign() < *AlignVal)) { 768 PtrAsInt = Builder.CreatePtrToInt(Ptr, IntPtrTy); 769 llvm::Value *Align = Builder.CreateAnd( 770 PtrAsInt, llvm::ConstantInt::get(IntPtrTy, AlignVal->value() - 1)); 771 llvm::Value *Aligned = 772 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0)); 773 if (Aligned != True) 774 Checks.push_back(std::make_pair(Aligned, SanitizerKind::Alignment)); 775 } 776 } 777 778 if (Checks.size() > 0) { 779 llvm::Constant *StaticData[] = { 780 EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(Ty), 781 llvm::ConstantInt::get(Int8Ty, AlignVal ? llvm::Log2(*AlignVal) : 1), 782 llvm::ConstantInt::get(Int8Ty, TCK)}; 783 EmitCheck(Checks, SanitizerHandler::TypeMismatch, StaticData, 784 PtrAsInt ? PtrAsInt : Ptr); 785 } 786 787 // If possible, check that the vptr indicates that there is a subobject of 788 // type Ty at offset zero within this object. 789 // 790 // C++11 [basic.life]p5,6: 791 // [For storage which does not refer to an object within its lifetime] 792 // The program has undefined behavior if: 793 // -- the [pointer or glvalue] is used to access a non-static data member 794 // or call a non-static member function 795 if (SanOpts.has(SanitizerKind::Vptr) && 796 !SkippedChecks.has(SanitizerKind::Vptr) && isVptrCheckRequired(TCK, Ty)) { 797 // Ensure that the pointer is non-null before loading it. If there is no 798 // compile-time guarantee, reuse the run-time null check or emit a new one. 799 if (!IsGuaranteedNonNull) { 800 if (!IsNonNull) 801 IsNonNull = Builder.CreateIsNotNull(Ptr); 802 if (!Done) 803 Done = createBasicBlock("vptr.null"); 804 llvm::BasicBlock *VptrNotNull = createBasicBlock("vptr.not.null"); 805 Builder.CreateCondBr(IsNonNull, VptrNotNull, Done); 806 EmitBlock(VptrNotNull); 807 } 808 809 // Compute a hash of the mangled name of the type. 810 // 811 // FIXME: This is not guaranteed to be deterministic! Move to a 812 // fingerprinting mechanism once LLVM provides one. For the time 813 // being the implementation happens to be deterministic. 814 SmallString<64> MangledName; 815 llvm::raw_svector_ostream Out(MangledName); 816 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(), 817 Out); 818 819 // Contained in NoSanitizeList based on the mangled type. 820 if (!CGM.getContext().getNoSanitizeList().containsType(SanitizerKind::Vptr, 821 Out.str())) { 822 llvm::hash_code TypeHash = hash_value(Out.str()); 823 824 // Load the vptr, and compute hash_16_bytes(TypeHash, vptr). 825 llvm::Value *Low = llvm::ConstantInt::get(Int64Ty, TypeHash); 826 Address VPtrAddr(Ptr, IntPtrTy, getPointerAlign()); 827 llvm::Value *VPtrVal = Builder.CreateLoad(VPtrAddr); 828 llvm::Value *High = Builder.CreateZExt(VPtrVal, Int64Ty); 829 830 llvm::Value *Hash = emitHash16Bytes(Builder, Low, High); 831 Hash = Builder.CreateTrunc(Hash, IntPtrTy); 832 833 // Look the hash up in our cache. 834 const int CacheSize = 128; 835 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize); 836 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable, 837 "__ubsan_vptr_type_cache"); 838 llvm::Value *Slot = Builder.CreateAnd(Hash, 839 llvm::ConstantInt::get(IntPtrTy, 840 CacheSize-1)); 841 llvm::Value *Indices[] = { Builder.getInt32(0), Slot }; 842 llvm::Value *CacheVal = Builder.CreateAlignedLoad( 843 IntPtrTy, Builder.CreateInBoundsGEP(HashTable, Cache, Indices), 844 getPointerAlign()); 845 846 // If the hash isn't in the cache, call a runtime handler to perform the 847 // hard work of checking whether the vptr is for an object of the right 848 // type. This will either fill in the cache and return, or produce a 849 // diagnostic. 850 llvm::Value *EqualHash = Builder.CreateICmpEQ(CacheVal, Hash); 851 llvm::Constant *StaticData[] = { 852 EmitCheckSourceLocation(Loc), 853 EmitCheckTypeDescriptor(Ty), 854 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()), 855 llvm::ConstantInt::get(Int8Ty, TCK) 856 }; 857 llvm::Value *DynamicData[] = { Ptr, Hash }; 858 EmitCheck(std::make_pair(EqualHash, SanitizerKind::Vptr), 859 SanitizerHandler::DynamicTypeCacheMiss, StaticData, 860 DynamicData); 861 } 862 } 863 864 if (Done) { 865 Builder.CreateBr(Done); 866 EmitBlock(Done); 867 } 868 } 869 870 llvm::Value *CodeGenFunction::LoadPassedObjectSize(const Expr *E, 871 QualType EltTy) { 872 ASTContext &C = getContext(); 873 uint64_t EltSize = C.getTypeSizeInChars(EltTy).getQuantity(); 874 if (!EltSize) 875 return nullptr; 876 877 auto *ArrayDeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts()); 878 if (!ArrayDeclRef) 879 return nullptr; 880 881 auto *ParamDecl = dyn_cast<ParmVarDecl>(ArrayDeclRef->getDecl()); 882 if (!ParamDecl) 883 return nullptr; 884 885 auto *POSAttr = ParamDecl->getAttr<PassObjectSizeAttr>(); 886 if (!POSAttr) 887 return nullptr; 888 889 // Don't load the size if it's a lower bound. 890 int POSType = POSAttr->getType(); 891 if (POSType != 0 && POSType != 1) 892 return nullptr; 893 894 // Find the implicit size parameter. 895 auto PassedSizeIt = SizeArguments.find(ParamDecl); 896 if (PassedSizeIt == SizeArguments.end()) 897 return nullptr; 898 899 const ImplicitParamDecl *PassedSizeDecl = PassedSizeIt->second; 900 assert(LocalDeclMap.count(PassedSizeDecl) && "Passed size not loadable"); 901 Address AddrOfSize = LocalDeclMap.find(PassedSizeDecl)->second; 902 llvm::Value *SizeInBytes = EmitLoadOfScalar(AddrOfSize, /*Volatile=*/false, 903 C.getSizeType(), E->getExprLoc()); 904 llvm::Value *SizeOfElement = 905 llvm::ConstantInt::get(SizeInBytes->getType(), EltSize); 906 return Builder.CreateUDiv(SizeInBytes, SizeOfElement); 907 } 908 909 /// If Base is known to point to the start of an array, return the length of 910 /// that array. Return 0 if the length cannot be determined. 911 static llvm::Value *getArrayIndexingBound(CodeGenFunction &CGF, 912 const Expr *Base, 913 QualType &IndexedType, 914 LangOptions::StrictFlexArraysLevelKind 915 StrictFlexArraysLevel) { 916 // For the vector indexing extension, the bound is the number of elements. 917 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) { 918 IndexedType = Base->getType(); 919 return CGF.Builder.getInt32(VT->getNumElements()); 920 } 921 922 Base = Base->IgnoreParens(); 923 924 if (const auto *CE = dyn_cast<CastExpr>(Base)) { 925 if (CE->getCastKind() == CK_ArrayToPointerDecay && 926 !CE->getSubExpr()->isFlexibleArrayMemberLike(CGF.getContext(), 927 StrictFlexArraysLevel)) { 928 IndexedType = CE->getSubExpr()->getType(); 929 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe(); 930 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT)) 931 return CGF.Builder.getInt(CAT->getSize()); 932 else if (const auto *VAT = dyn_cast<VariableArrayType>(AT)) 933 return CGF.getVLASize(VAT).NumElts; 934 // Ignore pass_object_size here. It's not applicable on decayed pointers. 935 } 936 } 937 938 QualType EltTy{Base->getType()->getPointeeOrArrayElementType(), 0}; 939 if (llvm::Value *POS = CGF.LoadPassedObjectSize(Base, EltTy)) { 940 IndexedType = Base->getType(); 941 return POS; 942 } 943 944 return nullptr; 945 } 946 947 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base, 948 llvm::Value *Index, QualType IndexType, 949 bool Accessed) { 950 assert(SanOpts.has(SanitizerKind::ArrayBounds) && 951 "should not be called unless adding bounds checks"); 952 SanitizerScope SanScope(this); 953 954 const LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel = 955 getLangOpts().getStrictFlexArraysLevel(); 956 957 QualType IndexedType; 958 llvm::Value *Bound = 959 getArrayIndexingBound(*this, Base, IndexedType, StrictFlexArraysLevel); 960 if (!Bound) 961 return; 962 963 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType(); 964 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned); 965 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false); 966 967 llvm::Constant *StaticData[] = { 968 EmitCheckSourceLocation(E->getExprLoc()), 969 EmitCheckTypeDescriptor(IndexedType), 970 EmitCheckTypeDescriptor(IndexType) 971 }; 972 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal) 973 : Builder.CreateICmpULE(IndexVal, BoundVal); 974 EmitCheck(std::make_pair(Check, SanitizerKind::ArrayBounds), 975 SanitizerHandler::OutOfBounds, StaticData, Index); 976 } 977 978 979 CodeGenFunction::ComplexPairTy CodeGenFunction:: 980 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV, 981 bool isInc, bool isPre) { 982 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc()); 983 984 llvm::Value *NextVal; 985 if (isa<llvm::IntegerType>(InVal.first->getType())) { 986 uint64_t AmountVal = isInc ? 1 : -1; 987 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true); 988 989 // Add the inc/dec to the real part. 990 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec"); 991 } else { 992 QualType ElemTy = E->getType()->castAs<ComplexType>()->getElementType(); 993 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1); 994 if (!isInc) 995 FVal.changeSign(); 996 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal); 997 998 // Add the inc/dec to the real part. 999 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec"); 1000 } 1001 1002 ComplexPairTy IncVal(NextVal, InVal.second); 1003 1004 // Store the updated result through the lvalue. 1005 EmitStoreOfComplex(IncVal, LV, /*init*/ false); 1006 if (getLangOpts().OpenMP) 1007 CGM.getOpenMPRuntime().checkAndEmitLastprivateConditional(*this, 1008 E->getSubExpr()); 1009 1010 // If this is a postinc, return the value read from memory, otherwise use the 1011 // updated value. 1012 return isPre ? IncVal : InVal; 1013 } 1014 1015 void CodeGenModule::EmitExplicitCastExprType(const ExplicitCastExpr *E, 1016 CodeGenFunction *CGF) { 1017 // Bind VLAs in the cast type. 1018 if (CGF && E->getType()->isVariablyModifiedType()) 1019 CGF->EmitVariablyModifiedType(E->getType()); 1020 1021 if (CGDebugInfo *DI = getModuleDebugInfo()) 1022 DI->EmitExplicitCastType(E->getType()); 1023 } 1024 1025 //===----------------------------------------------------------------------===// 1026 // LValue Expression Emission 1027 //===----------------------------------------------------------------------===// 1028 1029 static Address EmitPointerWithAlignment(const Expr *E, LValueBaseInfo *BaseInfo, 1030 TBAAAccessInfo *TBAAInfo, 1031 KnownNonNull_t IsKnownNonNull, 1032 CodeGenFunction &CGF) { 1033 // We allow this with ObjC object pointers because of fragile ABIs. 1034 assert(E->getType()->isPointerType() || 1035 E->getType()->isObjCObjectPointerType()); 1036 E = E->IgnoreParens(); 1037 1038 // Casts: 1039 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) { 1040 if (const auto *ECE = dyn_cast<ExplicitCastExpr>(CE)) 1041 CGF.CGM.EmitExplicitCastExprType(ECE, &CGF); 1042 1043 switch (CE->getCastKind()) { 1044 // Non-converting casts (but not C's implicit conversion from void*). 1045 case CK_BitCast: 1046 case CK_NoOp: 1047 case CK_AddressSpaceConversion: 1048 if (auto PtrTy = CE->getSubExpr()->getType()->getAs<PointerType>()) { 1049 if (PtrTy->getPointeeType()->isVoidType()) 1050 break; 1051 1052 LValueBaseInfo InnerBaseInfo; 1053 TBAAAccessInfo InnerTBAAInfo; 1054 Address Addr = CGF.EmitPointerWithAlignment( 1055 CE->getSubExpr(), &InnerBaseInfo, &InnerTBAAInfo, IsKnownNonNull); 1056 if (BaseInfo) *BaseInfo = InnerBaseInfo; 1057 if (TBAAInfo) *TBAAInfo = InnerTBAAInfo; 1058 1059 if (isa<ExplicitCastExpr>(CE)) { 1060 LValueBaseInfo TargetTypeBaseInfo; 1061 TBAAAccessInfo TargetTypeTBAAInfo; 1062 CharUnits Align = CGF.CGM.getNaturalPointeeTypeAlignment( 1063 E->getType(), &TargetTypeBaseInfo, &TargetTypeTBAAInfo); 1064 if (TBAAInfo) 1065 *TBAAInfo = 1066 CGF.CGM.mergeTBAAInfoForCast(*TBAAInfo, TargetTypeTBAAInfo); 1067 // If the source l-value is opaque, honor the alignment of the 1068 // casted-to type. 1069 if (InnerBaseInfo.getAlignmentSource() != AlignmentSource::Decl) { 1070 if (BaseInfo) 1071 BaseInfo->mergeForCast(TargetTypeBaseInfo); 1072 Addr = Address(Addr.getPointer(), Addr.getElementType(), Align, 1073 IsKnownNonNull); 1074 } 1075 } 1076 1077 if (CGF.SanOpts.has(SanitizerKind::CFIUnrelatedCast) && 1078 CE->getCastKind() == CK_BitCast) { 1079 if (auto PT = E->getType()->getAs<PointerType>()) 1080 CGF.EmitVTablePtrCheckForCast(PT->getPointeeType(), Addr, 1081 /*MayBeNull=*/true, 1082 CodeGenFunction::CFITCK_UnrelatedCast, 1083 CE->getBeginLoc()); 1084 } 1085 1086 llvm::Type *ElemTy = 1087 CGF.ConvertTypeForMem(E->getType()->getPointeeType()); 1088 Addr = Addr.withElementType(ElemTy); 1089 if (CE->getCastKind() == CK_AddressSpaceConversion) 1090 Addr = CGF.Builder.CreateAddrSpaceCast(Addr, 1091 CGF.ConvertType(E->getType())); 1092 return Addr; 1093 } 1094 break; 1095 1096 // Array-to-pointer decay. 1097 case CK_ArrayToPointerDecay: 1098 return CGF.EmitArrayToPointerDecay(CE->getSubExpr(), BaseInfo, TBAAInfo); 1099 1100 // Derived-to-base conversions. 1101 case CK_UncheckedDerivedToBase: 1102 case CK_DerivedToBase: { 1103 // TODO: Support accesses to members of base classes in TBAA. For now, we 1104 // conservatively pretend that the complete object is of the base class 1105 // type. 1106 if (TBAAInfo) 1107 *TBAAInfo = CGF.CGM.getTBAAAccessInfo(E->getType()); 1108 Address Addr = CGF.EmitPointerWithAlignment( 1109 CE->getSubExpr(), BaseInfo, nullptr, 1110 (KnownNonNull_t)(IsKnownNonNull || 1111 CE->getCastKind() == CK_UncheckedDerivedToBase)); 1112 auto Derived = CE->getSubExpr()->getType()->getPointeeCXXRecordDecl(); 1113 return CGF.GetAddressOfBaseClass( 1114 Addr, Derived, CE->path_begin(), CE->path_end(), 1115 CGF.ShouldNullCheckClassCastValue(CE), CE->getExprLoc()); 1116 } 1117 1118 // TODO: Is there any reason to treat base-to-derived conversions 1119 // specially? 1120 default: 1121 break; 1122 } 1123 } 1124 1125 // Unary &. 1126 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) { 1127 if (UO->getOpcode() == UO_AddrOf) { 1128 LValue LV = CGF.EmitLValue(UO->getSubExpr(), IsKnownNonNull); 1129 if (BaseInfo) *BaseInfo = LV.getBaseInfo(); 1130 if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo(); 1131 return LV.getAddress(CGF); 1132 } 1133 } 1134 1135 // std::addressof and variants. 1136 if (auto *Call = dyn_cast<CallExpr>(E)) { 1137 switch (Call->getBuiltinCallee()) { 1138 default: 1139 break; 1140 case Builtin::BIaddressof: 1141 case Builtin::BI__addressof: 1142 case Builtin::BI__builtin_addressof: { 1143 LValue LV = CGF.EmitLValue(Call->getArg(0), IsKnownNonNull); 1144 if (BaseInfo) *BaseInfo = LV.getBaseInfo(); 1145 if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo(); 1146 return LV.getAddress(CGF); 1147 } 1148 } 1149 } 1150 1151 // TODO: conditional operators, comma. 1152 1153 // Otherwise, use the alignment of the type. 1154 CharUnits Align = 1155 CGF.CGM.getNaturalPointeeTypeAlignment(E->getType(), BaseInfo, TBAAInfo); 1156 llvm::Type *ElemTy = CGF.ConvertTypeForMem(E->getType()->getPointeeType()); 1157 return Address(CGF.EmitScalarExpr(E), ElemTy, Align, IsKnownNonNull); 1158 } 1159 1160 /// EmitPointerWithAlignment - Given an expression of pointer type, try to 1161 /// derive a more accurate bound on the alignment of the pointer. 1162 Address CodeGenFunction::EmitPointerWithAlignment( 1163 const Expr *E, LValueBaseInfo *BaseInfo, TBAAAccessInfo *TBAAInfo, 1164 KnownNonNull_t IsKnownNonNull) { 1165 Address Addr = 1166 ::EmitPointerWithAlignment(E, BaseInfo, TBAAInfo, IsKnownNonNull, *this); 1167 if (IsKnownNonNull && !Addr.isKnownNonNull()) 1168 Addr.setKnownNonNull(); 1169 return Addr; 1170 } 1171 1172 llvm::Value *CodeGenFunction::EmitNonNullRValueCheck(RValue RV, QualType T) { 1173 llvm::Value *V = RV.getScalarVal(); 1174 if (auto MPT = T->getAs<MemberPointerType>()) 1175 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, V, MPT); 1176 return Builder.CreateICmpNE(V, llvm::Constant::getNullValue(V->getType())); 1177 } 1178 1179 RValue CodeGenFunction::GetUndefRValue(QualType Ty) { 1180 if (Ty->isVoidType()) 1181 return RValue::get(nullptr); 1182 1183 switch (getEvaluationKind(Ty)) { 1184 case TEK_Complex: { 1185 llvm::Type *EltTy = 1186 ConvertType(Ty->castAs<ComplexType>()->getElementType()); 1187 llvm::Value *U = llvm::UndefValue::get(EltTy); 1188 return RValue::getComplex(std::make_pair(U, U)); 1189 } 1190 1191 // If this is a use of an undefined aggregate type, the aggregate must have an 1192 // identifiable address. Just because the contents of the value are undefined 1193 // doesn't mean that the address can't be taken and compared. 1194 case TEK_Aggregate: { 1195 Address DestPtr = CreateMemTemp(Ty, "undef.agg.tmp"); 1196 return RValue::getAggregate(DestPtr); 1197 } 1198 1199 case TEK_Scalar: 1200 return RValue::get(llvm::UndefValue::get(ConvertType(Ty))); 1201 } 1202 llvm_unreachable("bad evaluation kind"); 1203 } 1204 1205 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E, 1206 const char *Name) { 1207 ErrorUnsupported(E, Name); 1208 return GetUndefRValue(E->getType()); 1209 } 1210 1211 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E, 1212 const char *Name) { 1213 ErrorUnsupported(E, Name); 1214 llvm::Type *ElTy = ConvertType(E->getType()); 1215 llvm::Type *Ty = UnqualPtrTy; 1216 return MakeAddrLValue( 1217 Address(llvm::UndefValue::get(Ty), ElTy, CharUnits::One()), E->getType()); 1218 } 1219 1220 bool CodeGenFunction::IsWrappedCXXThis(const Expr *Obj) { 1221 const Expr *Base = Obj; 1222 while (!isa<CXXThisExpr>(Base)) { 1223 // The result of a dynamic_cast can be null. 1224 if (isa<CXXDynamicCastExpr>(Base)) 1225 return false; 1226 1227 if (const auto *CE = dyn_cast<CastExpr>(Base)) { 1228 Base = CE->getSubExpr(); 1229 } else if (const auto *PE = dyn_cast<ParenExpr>(Base)) { 1230 Base = PE->getSubExpr(); 1231 } else if (const auto *UO = dyn_cast<UnaryOperator>(Base)) { 1232 if (UO->getOpcode() == UO_Extension) 1233 Base = UO->getSubExpr(); 1234 else 1235 return false; 1236 } else { 1237 return false; 1238 } 1239 } 1240 return true; 1241 } 1242 1243 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) { 1244 LValue LV; 1245 if (SanOpts.has(SanitizerKind::ArrayBounds) && isa<ArraySubscriptExpr>(E)) 1246 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true); 1247 else 1248 LV = EmitLValue(E); 1249 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) { 1250 SanitizerSet SkippedChecks; 1251 if (const auto *ME = dyn_cast<MemberExpr>(E)) { 1252 bool IsBaseCXXThis = IsWrappedCXXThis(ME->getBase()); 1253 if (IsBaseCXXThis) 1254 SkippedChecks.set(SanitizerKind::Alignment, true); 1255 if (IsBaseCXXThis || isa<DeclRefExpr>(ME->getBase())) 1256 SkippedChecks.set(SanitizerKind::Null, true); 1257 } 1258 EmitTypeCheck(TCK, E->getExprLoc(), LV.getPointer(*this), E->getType(), 1259 LV.getAlignment(), SkippedChecks); 1260 } 1261 return LV; 1262 } 1263 1264 /// EmitLValue - Emit code to compute a designator that specifies the location 1265 /// of the expression. 1266 /// 1267 /// This can return one of two things: a simple address or a bitfield reference. 1268 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be 1269 /// an LLVM pointer type. 1270 /// 1271 /// If this returns a bitfield reference, nothing about the pointee type of the 1272 /// LLVM value is known: For example, it may not be a pointer to an integer. 1273 /// 1274 /// If this returns a normal address, and if the lvalue's C type is fixed size, 1275 /// this method guarantees that the returned pointer type will point to an LLVM 1276 /// type of the same size of the lvalue's type. If the lvalue has a variable 1277 /// length type, this is not possible. 1278 /// 1279 LValue CodeGenFunction::EmitLValue(const Expr *E, 1280 KnownNonNull_t IsKnownNonNull) { 1281 LValue LV = EmitLValueHelper(E, IsKnownNonNull); 1282 if (IsKnownNonNull && !LV.isKnownNonNull()) 1283 LV.setKnownNonNull(); 1284 return LV; 1285 } 1286 1287 LValue CodeGenFunction::EmitLValueHelper(const Expr *E, 1288 KnownNonNull_t IsKnownNonNull) { 1289 ApplyDebugLocation DL(*this, E); 1290 switch (E->getStmtClass()) { 1291 default: return EmitUnsupportedLValue(E, "l-value expression"); 1292 1293 case Expr::ObjCPropertyRefExprClass: 1294 llvm_unreachable("cannot emit a property reference directly"); 1295 1296 case Expr::ObjCSelectorExprClass: 1297 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E)); 1298 case Expr::ObjCIsaExprClass: 1299 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E)); 1300 case Expr::BinaryOperatorClass: 1301 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E)); 1302 case Expr::CompoundAssignOperatorClass: { 1303 QualType Ty = E->getType(); 1304 if (const AtomicType *AT = Ty->getAs<AtomicType>()) 1305 Ty = AT->getValueType(); 1306 if (!Ty->isAnyComplexType()) 1307 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E)); 1308 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E)); 1309 } 1310 case Expr::CallExprClass: 1311 case Expr::CXXMemberCallExprClass: 1312 case Expr::CXXOperatorCallExprClass: 1313 case Expr::UserDefinedLiteralClass: 1314 return EmitCallExprLValue(cast<CallExpr>(E)); 1315 case Expr::CXXRewrittenBinaryOperatorClass: 1316 return EmitLValue(cast<CXXRewrittenBinaryOperator>(E)->getSemanticForm(), 1317 IsKnownNonNull); 1318 case Expr::VAArgExprClass: 1319 return EmitVAArgExprLValue(cast<VAArgExpr>(E)); 1320 case Expr::DeclRefExprClass: 1321 return EmitDeclRefLValue(cast<DeclRefExpr>(E)); 1322 case Expr::ConstantExprClass: { 1323 const ConstantExpr *CE = cast<ConstantExpr>(E); 1324 if (llvm::Value *Result = ConstantEmitter(*this).tryEmitConstantExpr(CE)) { 1325 QualType RetType = cast<CallExpr>(CE->getSubExpr()->IgnoreImplicit()) 1326 ->getCallReturnType(getContext()) 1327 ->getPointeeType(); 1328 return MakeNaturalAlignAddrLValue(Result, RetType); 1329 } 1330 return EmitLValue(cast<ConstantExpr>(E)->getSubExpr(), IsKnownNonNull); 1331 } 1332 case Expr::ParenExprClass: 1333 return EmitLValue(cast<ParenExpr>(E)->getSubExpr(), IsKnownNonNull); 1334 case Expr::GenericSelectionExprClass: 1335 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr(), 1336 IsKnownNonNull); 1337 case Expr::PredefinedExprClass: 1338 return EmitPredefinedLValue(cast<PredefinedExpr>(E)); 1339 case Expr::StringLiteralClass: 1340 return EmitStringLiteralLValue(cast<StringLiteral>(E)); 1341 case Expr::ObjCEncodeExprClass: 1342 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E)); 1343 case Expr::PseudoObjectExprClass: 1344 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E)); 1345 case Expr::InitListExprClass: 1346 return EmitInitListLValue(cast<InitListExpr>(E)); 1347 case Expr::CXXTemporaryObjectExprClass: 1348 case Expr::CXXConstructExprClass: 1349 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E)); 1350 case Expr::CXXBindTemporaryExprClass: 1351 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E)); 1352 case Expr::CXXUuidofExprClass: 1353 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E)); 1354 case Expr::LambdaExprClass: 1355 return EmitAggExprToLValue(E); 1356 1357 case Expr::ExprWithCleanupsClass: { 1358 const auto *cleanups = cast<ExprWithCleanups>(E); 1359 RunCleanupsScope Scope(*this); 1360 LValue LV = EmitLValue(cleanups->getSubExpr(), IsKnownNonNull); 1361 if (LV.isSimple()) { 1362 // Defend against branches out of gnu statement expressions surrounded by 1363 // cleanups. 1364 Address Addr = LV.getAddress(*this); 1365 llvm::Value *V = Addr.getPointer(); 1366 Scope.ForceCleanup({&V}); 1367 return LValue::MakeAddr(Addr.withPointer(V, Addr.isKnownNonNull()), 1368 LV.getType(), getContext(), LV.getBaseInfo(), 1369 LV.getTBAAInfo()); 1370 } 1371 // FIXME: Is it possible to create an ExprWithCleanups that produces a 1372 // bitfield lvalue or some other non-simple lvalue? 1373 return LV; 1374 } 1375 1376 case Expr::CXXDefaultArgExprClass: { 1377 auto *DAE = cast<CXXDefaultArgExpr>(E); 1378 CXXDefaultArgExprScope Scope(*this, DAE); 1379 return EmitLValue(DAE->getExpr(), IsKnownNonNull); 1380 } 1381 case Expr::CXXDefaultInitExprClass: { 1382 auto *DIE = cast<CXXDefaultInitExpr>(E); 1383 CXXDefaultInitExprScope Scope(*this, DIE); 1384 return EmitLValue(DIE->getExpr(), IsKnownNonNull); 1385 } 1386 case Expr::CXXTypeidExprClass: 1387 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E)); 1388 1389 case Expr::ObjCMessageExprClass: 1390 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E)); 1391 case Expr::ObjCIvarRefExprClass: 1392 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E)); 1393 case Expr::StmtExprClass: 1394 return EmitStmtExprLValue(cast<StmtExpr>(E)); 1395 case Expr::UnaryOperatorClass: 1396 return EmitUnaryOpLValue(cast<UnaryOperator>(E)); 1397 case Expr::ArraySubscriptExprClass: 1398 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E)); 1399 case Expr::MatrixSubscriptExprClass: 1400 return EmitMatrixSubscriptExpr(cast<MatrixSubscriptExpr>(E)); 1401 case Expr::OMPArraySectionExprClass: 1402 return EmitOMPArraySectionExpr(cast<OMPArraySectionExpr>(E)); 1403 case Expr::ExtVectorElementExprClass: 1404 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E)); 1405 case Expr::CXXThisExprClass: 1406 return MakeAddrLValue(LoadCXXThisAddress(), E->getType()); 1407 case Expr::MemberExprClass: 1408 return EmitMemberExpr(cast<MemberExpr>(E)); 1409 case Expr::CompoundLiteralExprClass: 1410 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E)); 1411 case Expr::ConditionalOperatorClass: 1412 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E)); 1413 case Expr::BinaryConditionalOperatorClass: 1414 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E)); 1415 case Expr::ChooseExprClass: 1416 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(), IsKnownNonNull); 1417 case Expr::OpaqueValueExprClass: 1418 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E)); 1419 case Expr::SubstNonTypeTemplateParmExprClass: 1420 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement(), 1421 IsKnownNonNull); 1422 case Expr::ImplicitCastExprClass: 1423 case Expr::CStyleCastExprClass: 1424 case Expr::CXXFunctionalCastExprClass: 1425 case Expr::CXXStaticCastExprClass: 1426 case Expr::CXXDynamicCastExprClass: 1427 case Expr::CXXReinterpretCastExprClass: 1428 case Expr::CXXConstCastExprClass: 1429 case Expr::CXXAddrspaceCastExprClass: 1430 case Expr::ObjCBridgedCastExprClass: 1431 return EmitCastLValue(cast<CastExpr>(E)); 1432 1433 case Expr::MaterializeTemporaryExprClass: 1434 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E)); 1435 1436 case Expr::CoawaitExprClass: 1437 return EmitCoawaitLValue(cast<CoawaitExpr>(E)); 1438 case Expr::CoyieldExprClass: 1439 return EmitCoyieldLValue(cast<CoyieldExpr>(E)); 1440 } 1441 } 1442 1443 /// Given an object of the given canonical type, can we safely copy a 1444 /// value out of it based on its initializer? 1445 static bool isConstantEmittableObjectType(QualType type) { 1446 assert(type.isCanonical()); 1447 assert(!type->isReferenceType()); 1448 1449 // Must be const-qualified but non-volatile. 1450 Qualifiers qs = type.getLocalQualifiers(); 1451 if (!qs.hasConst() || qs.hasVolatile()) return false; 1452 1453 // Otherwise, all object types satisfy this except C++ classes with 1454 // mutable subobjects or non-trivial copy/destroy behavior. 1455 if (const auto *RT = dyn_cast<RecordType>(type)) 1456 if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) 1457 if (RD->hasMutableFields() || !RD->isTrivial()) 1458 return false; 1459 1460 return true; 1461 } 1462 1463 /// Can we constant-emit a load of a reference to a variable of the 1464 /// given type? This is different from predicates like 1465 /// Decl::mightBeUsableInConstantExpressions because we do want it to apply 1466 /// in situations that don't necessarily satisfy the language's rules 1467 /// for this (e.g. C++'s ODR-use rules). For example, we want to able 1468 /// to do this with const float variables even if those variables 1469 /// aren't marked 'constexpr'. 1470 enum ConstantEmissionKind { 1471 CEK_None, 1472 CEK_AsReferenceOnly, 1473 CEK_AsValueOrReference, 1474 CEK_AsValueOnly 1475 }; 1476 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) { 1477 type = type.getCanonicalType(); 1478 if (const auto *ref = dyn_cast<ReferenceType>(type)) { 1479 if (isConstantEmittableObjectType(ref->getPointeeType())) 1480 return CEK_AsValueOrReference; 1481 return CEK_AsReferenceOnly; 1482 } 1483 if (isConstantEmittableObjectType(type)) 1484 return CEK_AsValueOnly; 1485 return CEK_None; 1486 } 1487 1488 /// Try to emit a reference to the given value without producing it as 1489 /// an l-value. This is just an optimization, but it avoids us needing 1490 /// to emit global copies of variables if they're named without triggering 1491 /// a formal use in a context where we can't emit a direct reference to them, 1492 /// for instance if a block or lambda or a member of a local class uses a 1493 /// const int variable or constexpr variable from an enclosing function. 1494 CodeGenFunction::ConstantEmission 1495 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) { 1496 ValueDecl *value = refExpr->getDecl(); 1497 1498 // The value needs to be an enum constant or a constant variable. 1499 ConstantEmissionKind CEK; 1500 if (isa<ParmVarDecl>(value)) { 1501 CEK = CEK_None; 1502 } else if (auto *var = dyn_cast<VarDecl>(value)) { 1503 CEK = checkVarTypeForConstantEmission(var->getType()); 1504 } else if (isa<EnumConstantDecl>(value)) { 1505 CEK = CEK_AsValueOnly; 1506 } else { 1507 CEK = CEK_None; 1508 } 1509 if (CEK == CEK_None) return ConstantEmission(); 1510 1511 Expr::EvalResult result; 1512 bool resultIsReference; 1513 QualType resultType; 1514 1515 // It's best to evaluate all the way as an r-value if that's permitted. 1516 if (CEK != CEK_AsReferenceOnly && 1517 refExpr->EvaluateAsRValue(result, getContext())) { 1518 resultIsReference = false; 1519 resultType = refExpr->getType(); 1520 1521 // Otherwise, try to evaluate as an l-value. 1522 } else if (CEK != CEK_AsValueOnly && 1523 refExpr->EvaluateAsLValue(result, getContext())) { 1524 resultIsReference = true; 1525 resultType = value->getType(); 1526 1527 // Failure. 1528 } else { 1529 return ConstantEmission(); 1530 } 1531 1532 // In any case, if the initializer has side-effects, abandon ship. 1533 if (result.HasSideEffects) 1534 return ConstantEmission(); 1535 1536 // In CUDA/HIP device compilation, a lambda may capture a reference variable 1537 // referencing a global host variable by copy. In this case the lambda should 1538 // make a copy of the value of the global host variable. The DRE of the 1539 // captured reference variable cannot be emitted as load from the host 1540 // global variable as compile time constant, since the host variable is not 1541 // accessible on device. The DRE of the captured reference variable has to be 1542 // loaded from captures. 1543 if (CGM.getLangOpts().CUDAIsDevice && result.Val.isLValue() && 1544 refExpr->refersToEnclosingVariableOrCapture()) { 1545 auto *MD = dyn_cast_or_null<CXXMethodDecl>(CurCodeDecl); 1546 if (MD && MD->getParent()->isLambda() && 1547 MD->getOverloadedOperator() == OO_Call) { 1548 const APValue::LValueBase &base = result.Val.getLValueBase(); 1549 if (const ValueDecl *D = base.dyn_cast<const ValueDecl *>()) { 1550 if (const VarDecl *VD = dyn_cast<const VarDecl>(D)) { 1551 if (!VD->hasAttr<CUDADeviceAttr>()) { 1552 return ConstantEmission(); 1553 } 1554 } 1555 } 1556 } 1557 } 1558 1559 // Emit as a constant. 1560 auto C = ConstantEmitter(*this).emitAbstract(refExpr->getLocation(), 1561 result.Val, resultType); 1562 1563 // Make sure we emit a debug reference to the global variable. 1564 // This should probably fire even for 1565 if (isa<VarDecl>(value)) { 1566 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value))) 1567 EmitDeclRefExprDbgValue(refExpr, result.Val); 1568 } else { 1569 assert(isa<EnumConstantDecl>(value)); 1570 EmitDeclRefExprDbgValue(refExpr, result.Val); 1571 } 1572 1573 // If we emitted a reference constant, we need to dereference that. 1574 if (resultIsReference) 1575 return ConstantEmission::forReference(C); 1576 1577 return ConstantEmission::forValue(C); 1578 } 1579 1580 static DeclRefExpr *tryToConvertMemberExprToDeclRefExpr(CodeGenFunction &CGF, 1581 const MemberExpr *ME) { 1582 if (auto *VD = dyn_cast<VarDecl>(ME->getMemberDecl())) { 1583 // Try to emit static variable member expressions as DREs. 1584 return DeclRefExpr::Create( 1585 CGF.getContext(), NestedNameSpecifierLoc(), SourceLocation(), VD, 1586 /*RefersToEnclosingVariableOrCapture=*/false, ME->getExprLoc(), 1587 ME->getType(), ME->getValueKind(), nullptr, nullptr, ME->isNonOdrUse()); 1588 } 1589 return nullptr; 1590 } 1591 1592 CodeGenFunction::ConstantEmission 1593 CodeGenFunction::tryEmitAsConstant(const MemberExpr *ME) { 1594 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, ME)) 1595 return tryEmitAsConstant(DRE); 1596 return ConstantEmission(); 1597 } 1598 1599 llvm::Value *CodeGenFunction::emitScalarConstant( 1600 const CodeGenFunction::ConstantEmission &Constant, Expr *E) { 1601 assert(Constant && "not a constant"); 1602 if (Constant.isReference()) 1603 return EmitLoadOfLValue(Constant.getReferenceLValue(*this, E), 1604 E->getExprLoc()) 1605 .getScalarVal(); 1606 return Constant.getValue(); 1607 } 1608 1609 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue, 1610 SourceLocation Loc) { 1611 return EmitLoadOfScalar(lvalue.getAddress(*this), lvalue.isVolatile(), 1612 lvalue.getType(), Loc, lvalue.getBaseInfo(), 1613 lvalue.getTBAAInfo(), lvalue.isNontemporal()); 1614 } 1615 1616 static bool hasBooleanRepresentation(QualType Ty) { 1617 if (Ty->isBooleanType()) 1618 return true; 1619 1620 if (const EnumType *ET = Ty->getAs<EnumType>()) 1621 return ET->getDecl()->getIntegerType()->isBooleanType(); 1622 1623 if (const AtomicType *AT = Ty->getAs<AtomicType>()) 1624 return hasBooleanRepresentation(AT->getValueType()); 1625 1626 return false; 1627 } 1628 1629 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty, 1630 llvm::APInt &Min, llvm::APInt &End, 1631 bool StrictEnums, bool IsBool) { 1632 const EnumType *ET = Ty->getAs<EnumType>(); 1633 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums && 1634 ET && !ET->getDecl()->isFixed(); 1635 if (!IsBool && !IsRegularCPlusPlusEnum) 1636 return false; 1637 1638 if (IsBool) { 1639 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0); 1640 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2); 1641 } else { 1642 const EnumDecl *ED = ET->getDecl(); 1643 ED->getValueRange(End, Min); 1644 } 1645 return true; 1646 } 1647 1648 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) { 1649 llvm::APInt Min, End; 1650 if (!getRangeForType(*this, Ty, Min, End, CGM.getCodeGenOpts().StrictEnums, 1651 hasBooleanRepresentation(Ty))) 1652 return nullptr; 1653 1654 llvm::MDBuilder MDHelper(getLLVMContext()); 1655 return MDHelper.createRange(Min, End); 1656 } 1657 1658 bool CodeGenFunction::EmitScalarRangeCheck(llvm::Value *Value, QualType Ty, 1659 SourceLocation Loc) { 1660 bool HasBoolCheck = SanOpts.has(SanitizerKind::Bool); 1661 bool HasEnumCheck = SanOpts.has(SanitizerKind::Enum); 1662 if (!HasBoolCheck && !HasEnumCheck) 1663 return false; 1664 1665 bool IsBool = hasBooleanRepresentation(Ty) || 1666 NSAPI(CGM.getContext()).isObjCBOOLType(Ty); 1667 bool NeedsBoolCheck = HasBoolCheck && IsBool; 1668 bool NeedsEnumCheck = HasEnumCheck && Ty->getAs<EnumType>(); 1669 if (!NeedsBoolCheck && !NeedsEnumCheck) 1670 return false; 1671 1672 // Single-bit booleans don't need to be checked. Special-case this to avoid 1673 // a bit width mismatch when handling bitfield values. This is handled by 1674 // EmitFromMemory for the non-bitfield case. 1675 if (IsBool && 1676 cast<llvm::IntegerType>(Value->getType())->getBitWidth() == 1) 1677 return false; 1678 1679 llvm::APInt Min, End; 1680 if (!getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true, IsBool)) 1681 return true; 1682 1683 auto &Ctx = getLLVMContext(); 1684 SanitizerScope SanScope(this); 1685 llvm::Value *Check; 1686 --End; 1687 if (!Min) { 1688 Check = Builder.CreateICmpULE(Value, llvm::ConstantInt::get(Ctx, End)); 1689 } else { 1690 llvm::Value *Upper = 1691 Builder.CreateICmpSLE(Value, llvm::ConstantInt::get(Ctx, End)); 1692 llvm::Value *Lower = 1693 Builder.CreateICmpSGE(Value, llvm::ConstantInt::get(Ctx, Min)); 1694 Check = Builder.CreateAnd(Upper, Lower); 1695 } 1696 llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc), 1697 EmitCheckTypeDescriptor(Ty)}; 1698 SanitizerMask Kind = 1699 NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool; 1700 EmitCheck(std::make_pair(Check, Kind), SanitizerHandler::LoadInvalidValue, 1701 StaticArgs, EmitCheckValue(Value)); 1702 return true; 1703 } 1704 1705 llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile, 1706 QualType Ty, 1707 SourceLocation Loc, 1708 LValueBaseInfo BaseInfo, 1709 TBAAAccessInfo TBAAInfo, 1710 bool isNontemporal) { 1711 if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr.getPointer())) 1712 if (GV->isThreadLocal()) 1713 Addr = Addr.withPointer(Builder.CreateThreadLocalAddress(GV), 1714 NotKnownNonNull); 1715 1716 if (const auto *ClangVecTy = Ty->getAs<VectorType>()) { 1717 // Boolean vectors use `iN` as storage type. 1718 if (ClangVecTy->isExtVectorBoolType()) { 1719 llvm::Type *ValTy = ConvertType(Ty); 1720 unsigned ValNumElems = 1721 cast<llvm::FixedVectorType>(ValTy)->getNumElements(); 1722 // Load the `iP` storage object (P is the padded vector size). 1723 auto *RawIntV = Builder.CreateLoad(Addr, Volatile, "load_bits"); 1724 const auto *RawIntTy = RawIntV->getType(); 1725 assert(RawIntTy->isIntegerTy() && "compressed iN storage for bitvectors"); 1726 // Bitcast iP --> <P x i1>. 1727 auto *PaddedVecTy = llvm::FixedVectorType::get( 1728 Builder.getInt1Ty(), RawIntTy->getPrimitiveSizeInBits()); 1729 llvm::Value *V = Builder.CreateBitCast(RawIntV, PaddedVecTy); 1730 // Shuffle <P x i1> --> <N x i1> (N is the actual bit size). 1731 V = emitBoolVecConversion(V, ValNumElems, "extractvec"); 1732 1733 return EmitFromMemory(V, Ty); 1734 } 1735 1736 // Handle vectors of size 3 like size 4 for better performance. 1737 const llvm::Type *EltTy = Addr.getElementType(); 1738 const auto *VTy = cast<llvm::FixedVectorType>(EltTy); 1739 1740 if (!CGM.getCodeGenOpts().PreserveVec3Type && VTy->getNumElements() == 3) { 1741 1742 llvm::VectorType *vec4Ty = 1743 llvm::FixedVectorType::get(VTy->getElementType(), 4); 1744 Address Cast = Addr.withElementType(vec4Ty); 1745 // Now load value. 1746 llvm::Value *V = Builder.CreateLoad(Cast, Volatile, "loadVec4"); 1747 1748 // Shuffle vector to get vec3. 1749 V = Builder.CreateShuffleVector(V, ArrayRef<int>{0, 1, 2}, "extractVec"); 1750 return EmitFromMemory(V, Ty); 1751 } 1752 } 1753 1754 // Atomic operations have to be done on integral types. 1755 LValue AtomicLValue = 1756 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo); 1757 if (Ty->isAtomicType() || LValueIsSuitableForInlineAtomic(AtomicLValue)) { 1758 return EmitAtomicLoad(AtomicLValue, Loc).getScalarVal(); 1759 } 1760 1761 llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile); 1762 if (isNontemporal) { 1763 llvm::MDNode *Node = llvm::MDNode::get( 1764 Load->getContext(), llvm::ConstantAsMetadata::get(Builder.getInt32(1))); 1765 Load->setMetadata(llvm::LLVMContext::MD_nontemporal, Node); 1766 } 1767 1768 CGM.DecorateInstructionWithTBAA(Load, TBAAInfo); 1769 1770 if (EmitScalarRangeCheck(Load, Ty, Loc)) { 1771 // In order to prevent the optimizer from throwing away the check, don't 1772 // attach range metadata to the load. 1773 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0) 1774 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty)) { 1775 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo); 1776 Load->setMetadata(llvm::LLVMContext::MD_noundef, 1777 llvm::MDNode::get(getLLVMContext(), std::nullopt)); 1778 } 1779 1780 return EmitFromMemory(Load, Ty); 1781 } 1782 1783 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) { 1784 // Bool has a different representation in memory than in registers. 1785 if (hasBooleanRepresentation(Ty)) { 1786 // This should really always be an i1, but sometimes it's already 1787 // an i8, and it's awkward to track those cases down. 1788 if (Value->getType()->isIntegerTy(1)) 1789 return Builder.CreateZExt(Value, ConvertTypeForMem(Ty), "frombool"); 1790 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) && 1791 "wrong value rep of bool"); 1792 } 1793 1794 return Value; 1795 } 1796 1797 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) { 1798 // Bool has a different representation in memory than in registers. 1799 if (hasBooleanRepresentation(Ty)) { 1800 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) && 1801 "wrong value rep of bool"); 1802 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool"); 1803 } 1804 if (Ty->isExtVectorBoolType()) { 1805 const auto *RawIntTy = Value->getType(); 1806 // Bitcast iP --> <P x i1>. 1807 auto *PaddedVecTy = llvm::FixedVectorType::get( 1808 Builder.getInt1Ty(), RawIntTy->getPrimitiveSizeInBits()); 1809 auto *V = Builder.CreateBitCast(Value, PaddedVecTy); 1810 // Shuffle <P x i1> --> <N x i1> (N is the actual bit size). 1811 llvm::Type *ValTy = ConvertType(Ty); 1812 unsigned ValNumElems = cast<llvm::FixedVectorType>(ValTy)->getNumElements(); 1813 return emitBoolVecConversion(V, ValNumElems, "extractvec"); 1814 } 1815 1816 return Value; 1817 } 1818 1819 // Convert the pointer of \p Addr to a pointer to a vector (the value type of 1820 // MatrixType), if it points to a array (the memory type of MatrixType). 1821 static Address MaybeConvertMatrixAddress(Address Addr, CodeGenFunction &CGF, 1822 bool IsVector = true) { 1823 auto *ArrayTy = dyn_cast<llvm::ArrayType>(Addr.getElementType()); 1824 if (ArrayTy && IsVector) { 1825 auto *VectorTy = llvm::FixedVectorType::get(ArrayTy->getElementType(), 1826 ArrayTy->getNumElements()); 1827 1828 return Addr.withElementType(VectorTy); 1829 } 1830 auto *VectorTy = dyn_cast<llvm::VectorType>(Addr.getElementType()); 1831 if (VectorTy && !IsVector) { 1832 auto *ArrayTy = llvm::ArrayType::get( 1833 VectorTy->getElementType(), 1834 cast<llvm::FixedVectorType>(VectorTy)->getNumElements()); 1835 1836 return Addr.withElementType(ArrayTy); 1837 } 1838 1839 return Addr; 1840 } 1841 1842 // Emit a store of a matrix LValue. This may require casting the original 1843 // pointer to memory address (ArrayType) to a pointer to the value type 1844 // (VectorType). 1845 static void EmitStoreOfMatrixScalar(llvm::Value *value, LValue lvalue, 1846 bool isInit, CodeGenFunction &CGF) { 1847 Address Addr = MaybeConvertMatrixAddress(lvalue.getAddress(CGF), CGF, 1848 value->getType()->isVectorTy()); 1849 CGF.EmitStoreOfScalar(value, Addr, lvalue.isVolatile(), lvalue.getType(), 1850 lvalue.getBaseInfo(), lvalue.getTBAAInfo(), isInit, 1851 lvalue.isNontemporal()); 1852 } 1853 1854 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr, 1855 bool Volatile, QualType Ty, 1856 LValueBaseInfo BaseInfo, 1857 TBAAAccessInfo TBAAInfo, 1858 bool isInit, bool isNontemporal) { 1859 if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr.getPointer())) 1860 if (GV->isThreadLocal()) 1861 Addr = Addr.withPointer(Builder.CreateThreadLocalAddress(GV), 1862 NotKnownNonNull); 1863 1864 llvm::Type *SrcTy = Value->getType(); 1865 if (const auto *ClangVecTy = Ty->getAs<VectorType>()) { 1866 auto *VecTy = dyn_cast<llvm::FixedVectorType>(SrcTy); 1867 if (VecTy && ClangVecTy->isExtVectorBoolType()) { 1868 auto *MemIntTy = cast<llvm::IntegerType>(Addr.getElementType()); 1869 // Expand to the memory bit width. 1870 unsigned MemNumElems = MemIntTy->getPrimitiveSizeInBits(); 1871 // <N x i1> --> <P x i1>. 1872 Value = emitBoolVecConversion(Value, MemNumElems, "insertvec"); 1873 // <P x i1> --> iP. 1874 Value = Builder.CreateBitCast(Value, MemIntTy); 1875 } else if (!CGM.getCodeGenOpts().PreserveVec3Type) { 1876 // Handle vec3 special. 1877 if (VecTy && cast<llvm::FixedVectorType>(VecTy)->getNumElements() == 3) { 1878 // Our source is a vec3, do a shuffle vector to make it a vec4. 1879 Value = Builder.CreateShuffleVector(Value, ArrayRef<int>{0, 1, 2, -1}, 1880 "extractVec"); 1881 SrcTy = llvm::FixedVectorType::get(VecTy->getElementType(), 4); 1882 } 1883 if (Addr.getElementType() != SrcTy) { 1884 Addr = Addr.withElementType(SrcTy); 1885 } 1886 } 1887 } 1888 1889 Value = EmitToMemory(Value, Ty); 1890 1891 LValue AtomicLValue = 1892 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo); 1893 if (Ty->isAtomicType() || 1894 (!isInit && LValueIsSuitableForInlineAtomic(AtomicLValue))) { 1895 EmitAtomicStore(RValue::get(Value), AtomicLValue, isInit); 1896 return; 1897 } 1898 1899 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile); 1900 if (isNontemporal) { 1901 llvm::MDNode *Node = 1902 llvm::MDNode::get(Store->getContext(), 1903 llvm::ConstantAsMetadata::get(Builder.getInt32(1))); 1904 Store->setMetadata(llvm::LLVMContext::MD_nontemporal, Node); 1905 } 1906 1907 CGM.DecorateInstructionWithTBAA(Store, TBAAInfo); 1908 } 1909 1910 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue, 1911 bool isInit) { 1912 if (lvalue.getType()->isConstantMatrixType()) { 1913 EmitStoreOfMatrixScalar(value, lvalue, isInit, *this); 1914 return; 1915 } 1916 1917 EmitStoreOfScalar(value, lvalue.getAddress(*this), lvalue.isVolatile(), 1918 lvalue.getType(), lvalue.getBaseInfo(), 1919 lvalue.getTBAAInfo(), isInit, lvalue.isNontemporal()); 1920 } 1921 1922 // Emit a load of a LValue of matrix type. This may require casting the pointer 1923 // to memory address (ArrayType) to a pointer to the value type (VectorType). 1924 static RValue EmitLoadOfMatrixLValue(LValue LV, SourceLocation Loc, 1925 CodeGenFunction &CGF) { 1926 assert(LV.getType()->isConstantMatrixType()); 1927 Address Addr = MaybeConvertMatrixAddress(LV.getAddress(CGF), CGF); 1928 LV.setAddress(Addr); 1929 return RValue::get(CGF.EmitLoadOfScalar(LV, Loc)); 1930 } 1931 1932 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this 1933 /// method emits the address of the lvalue, then loads the result as an rvalue, 1934 /// returning the rvalue. 1935 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) { 1936 if (LV.isObjCWeak()) { 1937 // load of a __weak object. 1938 Address AddrWeakObj = LV.getAddress(*this); 1939 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this, 1940 AddrWeakObj)); 1941 } 1942 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) { 1943 // In MRC mode, we do a load+autorelease. 1944 if (!getLangOpts().ObjCAutoRefCount) { 1945 return RValue::get(EmitARCLoadWeak(LV.getAddress(*this))); 1946 } 1947 1948 // In ARC mode, we load retained and then consume the value. 1949 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress(*this)); 1950 Object = EmitObjCConsumeObject(LV.getType(), Object); 1951 return RValue::get(Object); 1952 } 1953 1954 if (LV.isSimple()) { 1955 assert(!LV.getType()->isFunctionType()); 1956 1957 if (LV.getType()->isConstantMatrixType()) 1958 return EmitLoadOfMatrixLValue(LV, Loc, *this); 1959 1960 // Everything needs a load. 1961 return RValue::get(EmitLoadOfScalar(LV, Loc)); 1962 } 1963 1964 if (LV.isVectorElt()) { 1965 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddress(), 1966 LV.isVolatileQualified()); 1967 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(), 1968 "vecext")); 1969 } 1970 1971 // If this is a reference to a subset of the elements of a vector, either 1972 // shuffle the input or extract/insert them as appropriate. 1973 if (LV.isExtVectorElt()) { 1974 return EmitLoadOfExtVectorElementLValue(LV); 1975 } 1976 1977 // Global Register variables always invoke intrinsics 1978 if (LV.isGlobalReg()) 1979 return EmitLoadOfGlobalRegLValue(LV); 1980 1981 if (LV.isMatrixElt()) { 1982 llvm::Value *Idx = LV.getMatrixIdx(); 1983 if (CGM.getCodeGenOpts().OptimizationLevel > 0) { 1984 const auto *const MatTy = LV.getType()->castAs<ConstantMatrixType>(); 1985 llvm::MatrixBuilder MB(Builder); 1986 MB.CreateIndexAssumption(Idx, MatTy->getNumElementsFlattened()); 1987 } 1988 llvm::LoadInst *Load = 1989 Builder.CreateLoad(LV.getMatrixAddress(), LV.isVolatileQualified()); 1990 return RValue::get(Builder.CreateExtractElement(Load, Idx, "matrixext")); 1991 } 1992 1993 assert(LV.isBitField() && "Unknown LValue type!"); 1994 return EmitLoadOfBitfieldLValue(LV, Loc); 1995 } 1996 1997 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV, 1998 SourceLocation Loc) { 1999 const CGBitFieldInfo &Info = LV.getBitFieldInfo(); 2000 2001 // Get the output type. 2002 llvm::Type *ResLTy = ConvertType(LV.getType()); 2003 2004 Address Ptr = LV.getBitFieldAddress(); 2005 llvm::Value *Val = 2006 Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "bf.load"); 2007 2008 bool UseVolatile = LV.isVolatileQualified() && 2009 Info.VolatileStorageSize != 0 && isAAPCS(CGM.getTarget()); 2010 const unsigned Offset = UseVolatile ? Info.VolatileOffset : Info.Offset; 2011 const unsigned StorageSize = 2012 UseVolatile ? Info.VolatileStorageSize : Info.StorageSize; 2013 if (Info.IsSigned) { 2014 assert(static_cast<unsigned>(Offset + Info.Size) <= StorageSize); 2015 unsigned HighBits = StorageSize - Offset - Info.Size; 2016 if (HighBits) 2017 Val = Builder.CreateShl(Val, HighBits, "bf.shl"); 2018 if (Offset + HighBits) 2019 Val = Builder.CreateAShr(Val, Offset + HighBits, "bf.ashr"); 2020 } else { 2021 if (Offset) 2022 Val = Builder.CreateLShr(Val, Offset, "bf.lshr"); 2023 if (static_cast<unsigned>(Offset) + Info.Size < StorageSize) 2024 Val = Builder.CreateAnd( 2025 Val, llvm::APInt::getLowBitsSet(StorageSize, Info.Size), "bf.clear"); 2026 } 2027 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast"); 2028 EmitScalarRangeCheck(Val, LV.getType(), Loc); 2029 return RValue::get(Val); 2030 } 2031 2032 // If this is a reference to a subset of the elements of a vector, create an 2033 // appropriate shufflevector. 2034 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) { 2035 llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddress(), 2036 LV.isVolatileQualified()); 2037 2038 // HLSL allows treating scalars as one-element vectors. Converting the scalar 2039 // IR value to a vector here allows the rest of codegen to behave as normal. 2040 if (getLangOpts().HLSL && !Vec->getType()->isVectorTy()) { 2041 llvm::Type *DstTy = llvm::FixedVectorType::get(Vec->getType(), 1); 2042 llvm::Value *Zero = llvm::Constant::getNullValue(CGM.Int64Ty); 2043 Vec = Builder.CreateInsertElement(DstTy, Vec, Zero, "cast.splat"); 2044 } 2045 2046 const llvm::Constant *Elts = LV.getExtVectorElts(); 2047 2048 // If the result of the expression is a non-vector type, we must be extracting 2049 // a single element. Just codegen as an extractelement. 2050 const VectorType *ExprVT = LV.getType()->getAs<VectorType>(); 2051 if (!ExprVT) { 2052 unsigned InIdx = getAccessedFieldNo(0, Elts); 2053 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx); 2054 return RValue::get(Builder.CreateExtractElement(Vec, Elt)); 2055 } 2056 2057 // Always use shuffle vector to try to retain the original program structure 2058 unsigned NumResultElts = ExprVT->getNumElements(); 2059 2060 SmallVector<int, 4> Mask; 2061 for (unsigned i = 0; i != NumResultElts; ++i) 2062 Mask.push_back(getAccessedFieldNo(i, Elts)); 2063 2064 Vec = Builder.CreateShuffleVector(Vec, Mask); 2065 return RValue::get(Vec); 2066 } 2067 2068 /// Generates lvalue for partial ext_vector access. 2069 Address CodeGenFunction::EmitExtVectorElementLValue(LValue LV) { 2070 Address VectorAddress = LV.getExtVectorAddress(); 2071 QualType EQT = LV.getType()->castAs<VectorType>()->getElementType(); 2072 llvm::Type *VectorElementTy = CGM.getTypes().ConvertType(EQT); 2073 2074 Address CastToPointerElement = VectorAddress.withElementType(VectorElementTy); 2075 2076 const llvm::Constant *Elts = LV.getExtVectorElts(); 2077 unsigned ix = getAccessedFieldNo(0, Elts); 2078 2079 Address VectorBasePtrPlusIx = 2080 Builder.CreateConstInBoundsGEP(CastToPointerElement, ix, 2081 "vector.elt"); 2082 2083 return VectorBasePtrPlusIx; 2084 } 2085 2086 /// Load of global gamed gegisters are always calls to intrinsics. 2087 RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) { 2088 assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) && 2089 "Bad type for register variable"); 2090 llvm::MDNode *RegName = cast<llvm::MDNode>( 2091 cast<llvm::MetadataAsValue>(LV.getGlobalReg())->getMetadata()); 2092 2093 // We accept integer and pointer types only 2094 llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType()); 2095 llvm::Type *Ty = OrigTy; 2096 if (OrigTy->isPointerTy()) 2097 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy); 2098 llvm::Type *Types[] = { Ty }; 2099 2100 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types); 2101 llvm::Value *Call = Builder.CreateCall( 2102 F, llvm::MetadataAsValue::get(Ty->getContext(), RegName)); 2103 if (OrigTy->isPointerTy()) 2104 Call = Builder.CreateIntToPtr(Call, OrigTy); 2105 return RValue::get(Call); 2106 } 2107 2108 /// EmitStoreThroughLValue - Store the specified rvalue into the specified 2109 /// lvalue, where both are guaranteed to the have the same type, and that type 2110 /// is 'Ty'. 2111 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst, 2112 bool isInit) { 2113 if (!Dst.isSimple()) { 2114 if (Dst.isVectorElt()) { 2115 // Read/modify/write the vector, inserting the new element. 2116 llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddress(), 2117 Dst.isVolatileQualified()); 2118 auto *IRStoreTy = dyn_cast<llvm::IntegerType>(Vec->getType()); 2119 if (IRStoreTy) { 2120 auto *IRVecTy = llvm::FixedVectorType::get( 2121 Builder.getInt1Ty(), IRStoreTy->getPrimitiveSizeInBits()); 2122 Vec = Builder.CreateBitCast(Vec, IRVecTy); 2123 // iN --> <N x i1>. 2124 } 2125 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(), 2126 Dst.getVectorIdx(), "vecins"); 2127 if (IRStoreTy) { 2128 // <N x i1> --> <iN>. 2129 Vec = Builder.CreateBitCast(Vec, IRStoreTy); 2130 } 2131 Builder.CreateStore(Vec, Dst.getVectorAddress(), 2132 Dst.isVolatileQualified()); 2133 return; 2134 } 2135 2136 // If this is an update of extended vector elements, insert them as 2137 // appropriate. 2138 if (Dst.isExtVectorElt()) 2139 return EmitStoreThroughExtVectorComponentLValue(Src, Dst); 2140 2141 if (Dst.isGlobalReg()) 2142 return EmitStoreThroughGlobalRegLValue(Src, Dst); 2143 2144 if (Dst.isMatrixElt()) { 2145 llvm::Value *Idx = Dst.getMatrixIdx(); 2146 if (CGM.getCodeGenOpts().OptimizationLevel > 0) { 2147 const auto *const MatTy = Dst.getType()->castAs<ConstantMatrixType>(); 2148 llvm::MatrixBuilder MB(Builder); 2149 MB.CreateIndexAssumption(Idx, MatTy->getNumElementsFlattened()); 2150 } 2151 llvm::Instruction *Load = Builder.CreateLoad(Dst.getMatrixAddress()); 2152 llvm::Value *Vec = 2153 Builder.CreateInsertElement(Load, Src.getScalarVal(), Idx, "matins"); 2154 Builder.CreateStore(Vec, Dst.getMatrixAddress(), 2155 Dst.isVolatileQualified()); 2156 return; 2157 } 2158 2159 assert(Dst.isBitField() && "Unknown LValue type"); 2160 return EmitStoreThroughBitfieldLValue(Src, Dst); 2161 } 2162 2163 // There's special magic for assigning into an ARC-qualified l-value. 2164 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) { 2165 switch (Lifetime) { 2166 case Qualifiers::OCL_None: 2167 llvm_unreachable("present but none"); 2168 2169 case Qualifiers::OCL_ExplicitNone: 2170 // nothing special 2171 break; 2172 2173 case Qualifiers::OCL_Strong: 2174 if (isInit) { 2175 Src = RValue::get(EmitARCRetain(Dst.getType(), Src.getScalarVal())); 2176 break; 2177 } 2178 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true); 2179 return; 2180 2181 case Qualifiers::OCL_Weak: 2182 if (isInit) 2183 // Initialize and then skip the primitive store. 2184 EmitARCInitWeak(Dst.getAddress(*this), Src.getScalarVal()); 2185 else 2186 EmitARCStoreWeak(Dst.getAddress(*this), Src.getScalarVal(), 2187 /*ignore*/ true); 2188 return; 2189 2190 case Qualifiers::OCL_Autoreleasing: 2191 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(), 2192 Src.getScalarVal())); 2193 // fall into the normal path 2194 break; 2195 } 2196 } 2197 2198 if (Dst.isObjCWeak() && !Dst.isNonGC()) { 2199 // load of a __weak object. 2200 Address LvalueDst = Dst.getAddress(*this); 2201 llvm::Value *src = Src.getScalarVal(); 2202 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst); 2203 return; 2204 } 2205 2206 if (Dst.isObjCStrong() && !Dst.isNonGC()) { 2207 // load of a __strong object. 2208 Address LvalueDst = Dst.getAddress(*this); 2209 llvm::Value *src = Src.getScalarVal(); 2210 if (Dst.isObjCIvar()) { 2211 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL"); 2212 llvm::Type *ResultType = IntPtrTy; 2213 Address dst = EmitPointerWithAlignment(Dst.getBaseIvarExp()); 2214 llvm::Value *RHS = dst.getPointer(); 2215 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 2216 llvm::Value *LHS = 2217 Builder.CreatePtrToInt(LvalueDst.getPointer(), ResultType, 2218 "sub.ptr.lhs.cast"); 2219 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset"); 2220 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst, 2221 BytesBetween); 2222 } else if (Dst.isGlobalObjCRef()) { 2223 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst, 2224 Dst.isThreadLocalRef()); 2225 } 2226 else 2227 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst); 2228 return; 2229 } 2230 2231 assert(Src.isScalar() && "Can't emit an agg store with this method"); 2232 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit); 2233 } 2234 2235 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst, 2236 llvm::Value **Result) { 2237 const CGBitFieldInfo &Info = Dst.getBitFieldInfo(); 2238 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType()); 2239 Address Ptr = Dst.getBitFieldAddress(); 2240 2241 // Get the source value, truncated to the width of the bit-field. 2242 llvm::Value *SrcVal = Src.getScalarVal(); 2243 2244 // Cast the source to the storage type and shift it into place. 2245 SrcVal = Builder.CreateIntCast(SrcVal, Ptr.getElementType(), 2246 /*isSigned=*/false); 2247 llvm::Value *MaskedVal = SrcVal; 2248 2249 const bool UseVolatile = 2250 CGM.getCodeGenOpts().AAPCSBitfieldWidth && Dst.isVolatileQualified() && 2251 Info.VolatileStorageSize != 0 && isAAPCS(CGM.getTarget()); 2252 const unsigned StorageSize = 2253 UseVolatile ? Info.VolatileStorageSize : Info.StorageSize; 2254 const unsigned Offset = UseVolatile ? Info.VolatileOffset : Info.Offset; 2255 // See if there are other bits in the bitfield's storage we'll need to load 2256 // and mask together with source before storing. 2257 if (StorageSize != Info.Size) { 2258 assert(StorageSize > Info.Size && "Invalid bitfield size."); 2259 llvm::Value *Val = 2260 Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.load"); 2261 2262 // Mask the source value as needed. 2263 if (!hasBooleanRepresentation(Dst.getType())) 2264 SrcVal = Builder.CreateAnd( 2265 SrcVal, llvm::APInt::getLowBitsSet(StorageSize, Info.Size), 2266 "bf.value"); 2267 MaskedVal = SrcVal; 2268 if (Offset) 2269 SrcVal = Builder.CreateShl(SrcVal, Offset, "bf.shl"); 2270 2271 // Mask out the original value. 2272 Val = Builder.CreateAnd( 2273 Val, ~llvm::APInt::getBitsSet(StorageSize, Offset, Offset + Info.Size), 2274 "bf.clear"); 2275 2276 // Or together the unchanged values and the source value. 2277 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set"); 2278 } else { 2279 assert(Offset == 0); 2280 // According to the AACPS: 2281 // When a volatile bit-field is written, and its container does not overlap 2282 // with any non-bit-field member, its container must be read exactly once 2283 // and written exactly once using the access width appropriate to the type 2284 // of the container. The two accesses are not atomic. 2285 if (Dst.isVolatileQualified() && isAAPCS(CGM.getTarget()) && 2286 CGM.getCodeGenOpts().ForceAAPCSBitfieldLoad) 2287 Builder.CreateLoad(Ptr, true, "bf.load"); 2288 } 2289 2290 // Write the new value back out. 2291 Builder.CreateStore(SrcVal, Ptr, Dst.isVolatileQualified()); 2292 2293 // Return the new value of the bit-field, if requested. 2294 if (Result) { 2295 llvm::Value *ResultVal = MaskedVal; 2296 2297 // Sign extend the value if needed. 2298 if (Info.IsSigned) { 2299 assert(Info.Size <= StorageSize); 2300 unsigned HighBits = StorageSize - Info.Size; 2301 if (HighBits) { 2302 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl"); 2303 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr"); 2304 } 2305 } 2306 2307 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned, 2308 "bf.result.cast"); 2309 *Result = EmitFromMemory(ResultVal, Dst.getType()); 2310 } 2311 } 2312 2313 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src, 2314 LValue Dst) { 2315 // HLSL allows storing to scalar values through ExtVector component LValues. 2316 // To support this we need to handle the case where the destination address is 2317 // a scalar. 2318 Address DstAddr = Dst.getExtVectorAddress(); 2319 if (!DstAddr.getElementType()->isVectorTy()) { 2320 assert(!Dst.getType()->isVectorType() && 2321 "this should only occur for non-vector l-values"); 2322 Builder.CreateStore(Src.getScalarVal(), DstAddr, Dst.isVolatileQualified()); 2323 return; 2324 } 2325 2326 // This access turns into a read/modify/write of the vector. Load the input 2327 // value now. 2328 llvm::Value *Vec = Builder.CreateLoad(DstAddr, Dst.isVolatileQualified()); 2329 const llvm::Constant *Elts = Dst.getExtVectorElts(); 2330 2331 llvm::Value *SrcVal = Src.getScalarVal(); 2332 2333 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) { 2334 unsigned NumSrcElts = VTy->getNumElements(); 2335 unsigned NumDstElts = 2336 cast<llvm::FixedVectorType>(Vec->getType())->getNumElements(); 2337 if (NumDstElts == NumSrcElts) { 2338 // Use shuffle vector is the src and destination are the same number of 2339 // elements and restore the vector mask since it is on the side it will be 2340 // stored. 2341 SmallVector<int, 4> Mask(NumDstElts); 2342 for (unsigned i = 0; i != NumSrcElts; ++i) 2343 Mask[getAccessedFieldNo(i, Elts)] = i; 2344 2345 Vec = Builder.CreateShuffleVector(SrcVal, Mask); 2346 } else if (NumDstElts > NumSrcElts) { 2347 // Extended the source vector to the same length and then shuffle it 2348 // into the destination. 2349 // FIXME: since we're shuffling with undef, can we just use the indices 2350 // into that? This could be simpler. 2351 SmallVector<int, 4> ExtMask; 2352 for (unsigned i = 0; i != NumSrcElts; ++i) 2353 ExtMask.push_back(i); 2354 ExtMask.resize(NumDstElts, -1); 2355 llvm::Value *ExtSrcVal = Builder.CreateShuffleVector(SrcVal, ExtMask); 2356 // build identity 2357 SmallVector<int, 4> Mask; 2358 for (unsigned i = 0; i != NumDstElts; ++i) 2359 Mask.push_back(i); 2360 2361 // When the vector size is odd and .odd or .hi is used, the last element 2362 // of the Elts constant array will be one past the size of the vector. 2363 // Ignore the last element here, if it is greater than the mask size. 2364 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size()) 2365 NumSrcElts--; 2366 2367 // modify when what gets shuffled in 2368 for (unsigned i = 0; i != NumSrcElts; ++i) 2369 Mask[getAccessedFieldNo(i, Elts)] = i + NumDstElts; 2370 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, Mask); 2371 } else { 2372 // We should never shorten the vector 2373 llvm_unreachable("unexpected shorten vector length"); 2374 } 2375 } else { 2376 // If the Src is a scalar (not a vector), and the target is a vector it must 2377 // be updating one element. 2378 unsigned InIdx = getAccessedFieldNo(0, Elts); 2379 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx); 2380 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt); 2381 } 2382 2383 Builder.CreateStore(Vec, Dst.getExtVectorAddress(), 2384 Dst.isVolatileQualified()); 2385 } 2386 2387 /// Store of global named registers are always calls to intrinsics. 2388 void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) { 2389 assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) && 2390 "Bad type for register variable"); 2391 llvm::MDNode *RegName = cast<llvm::MDNode>( 2392 cast<llvm::MetadataAsValue>(Dst.getGlobalReg())->getMetadata()); 2393 assert(RegName && "Register LValue is not metadata"); 2394 2395 // We accept integer and pointer types only 2396 llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType()); 2397 llvm::Type *Ty = OrigTy; 2398 if (OrigTy->isPointerTy()) 2399 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy); 2400 llvm::Type *Types[] = { Ty }; 2401 2402 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types); 2403 llvm::Value *Value = Src.getScalarVal(); 2404 if (OrigTy->isPointerTy()) 2405 Value = Builder.CreatePtrToInt(Value, Ty); 2406 Builder.CreateCall( 2407 F, {llvm::MetadataAsValue::get(Ty->getContext(), RegName), Value}); 2408 } 2409 2410 // setObjCGCLValueClass - sets class of the lvalue for the purpose of 2411 // generating write-barries API. It is currently a global, ivar, 2412 // or neither. 2413 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E, 2414 LValue &LV, 2415 bool IsMemberAccess=false) { 2416 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC) 2417 return; 2418 2419 if (isa<ObjCIvarRefExpr>(E)) { 2420 QualType ExpTy = E->getType(); 2421 if (IsMemberAccess && ExpTy->isPointerType()) { 2422 // If ivar is a structure pointer, assigning to field of 2423 // this struct follows gcc's behavior and makes it a non-ivar 2424 // writer-barrier conservatively. 2425 ExpTy = ExpTy->castAs<PointerType>()->getPointeeType(); 2426 if (ExpTy->isRecordType()) { 2427 LV.setObjCIvar(false); 2428 return; 2429 } 2430 } 2431 LV.setObjCIvar(true); 2432 auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E)); 2433 LV.setBaseIvarExp(Exp->getBase()); 2434 LV.setObjCArray(E->getType()->isArrayType()); 2435 return; 2436 } 2437 2438 if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) { 2439 if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) { 2440 if (VD->hasGlobalStorage()) { 2441 LV.setGlobalObjCRef(true); 2442 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None); 2443 } 2444 } 2445 LV.setObjCArray(E->getType()->isArrayType()); 2446 return; 2447 } 2448 2449 if (const auto *Exp = dyn_cast<UnaryOperator>(E)) { 2450 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2451 return; 2452 } 2453 2454 if (const auto *Exp = dyn_cast<ParenExpr>(E)) { 2455 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2456 if (LV.isObjCIvar()) { 2457 // If cast is to a structure pointer, follow gcc's behavior and make it 2458 // a non-ivar write-barrier. 2459 QualType ExpTy = E->getType(); 2460 if (ExpTy->isPointerType()) 2461 ExpTy = ExpTy->castAs<PointerType>()->getPointeeType(); 2462 if (ExpTy->isRecordType()) 2463 LV.setObjCIvar(false); 2464 } 2465 return; 2466 } 2467 2468 if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) { 2469 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV); 2470 return; 2471 } 2472 2473 if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) { 2474 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2475 return; 2476 } 2477 2478 if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) { 2479 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2480 return; 2481 } 2482 2483 if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) { 2484 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2485 return; 2486 } 2487 2488 if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) { 2489 setObjCGCLValueClass(Ctx, Exp->getBase(), LV); 2490 if (LV.isObjCIvar() && !LV.isObjCArray()) 2491 // Using array syntax to assigning to what an ivar points to is not 2492 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0; 2493 LV.setObjCIvar(false); 2494 else if (LV.isGlobalObjCRef() && !LV.isObjCArray()) 2495 // Using array syntax to assigning to what global points to is not 2496 // same as assigning to the global itself. {id *G;} G[i] = 0; 2497 LV.setGlobalObjCRef(false); 2498 return; 2499 } 2500 2501 if (const auto *Exp = dyn_cast<MemberExpr>(E)) { 2502 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true); 2503 // We don't know if member is an 'ivar', but this flag is looked at 2504 // only in the context of LV.isObjCIvar(). 2505 LV.setObjCArray(E->getType()->isArrayType()); 2506 return; 2507 } 2508 } 2509 2510 static LValue EmitThreadPrivateVarDeclLValue( 2511 CodeGenFunction &CGF, const VarDecl *VD, QualType T, Address Addr, 2512 llvm::Type *RealVarTy, SourceLocation Loc) { 2513 if (CGF.CGM.getLangOpts().OpenMPIRBuilder) 2514 Addr = CodeGenFunction::OMPBuilderCBHelpers::getAddrOfThreadPrivate( 2515 CGF, VD, Addr, Loc); 2516 else 2517 Addr = 2518 CGF.CGM.getOpenMPRuntime().getAddrOfThreadPrivate(CGF, VD, Addr, Loc); 2519 2520 Addr = Addr.withElementType(RealVarTy); 2521 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl); 2522 } 2523 2524 static Address emitDeclTargetVarDeclLValue(CodeGenFunction &CGF, 2525 const VarDecl *VD, QualType T) { 2526 std::optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res = 2527 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD); 2528 // Return an invalid address if variable is MT_To (or MT_Enter starting with 2529 // OpenMP 5.2) and unified memory is not enabled. For all other cases: MT_Link 2530 // and MT_To (or MT_Enter) with unified memory, return a valid address. 2531 if (!Res || ((*Res == OMPDeclareTargetDeclAttr::MT_To || 2532 *Res == OMPDeclareTargetDeclAttr::MT_Enter) && 2533 !CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory())) 2534 return Address::invalid(); 2535 assert(((*Res == OMPDeclareTargetDeclAttr::MT_Link) || 2536 ((*Res == OMPDeclareTargetDeclAttr::MT_To || 2537 *Res == OMPDeclareTargetDeclAttr::MT_Enter) && 2538 CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory())) && 2539 "Expected link clause OR to clause with unified memory enabled."); 2540 QualType PtrTy = CGF.getContext().getPointerType(VD->getType()); 2541 Address Addr = CGF.CGM.getOpenMPRuntime().getAddrOfDeclareTargetVar(VD); 2542 return CGF.EmitLoadOfPointer(Addr, PtrTy->castAs<PointerType>()); 2543 } 2544 2545 Address 2546 CodeGenFunction::EmitLoadOfReference(LValue RefLVal, 2547 LValueBaseInfo *PointeeBaseInfo, 2548 TBAAAccessInfo *PointeeTBAAInfo) { 2549 llvm::LoadInst *Load = 2550 Builder.CreateLoad(RefLVal.getAddress(*this), RefLVal.isVolatile()); 2551 CGM.DecorateInstructionWithTBAA(Load, RefLVal.getTBAAInfo()); 2552 2553 QualType PointeeType = RefLVal.getType()->getPointeeType(); 2554 CharUnits Align = CGM.getNaturalTypeAlignment( 2555 PointeeType, PointeeBaseInfo, PointeeTBAAInfo, 2556 /* forPointeeType= */ true); 2557 return Address(Load, ConvertTypeForMem(PointeeType), Align); 2558 } 2559 2560 LValue CodeGenFunction::EmitLoadOfReferenceLValue(LValue RefLVal) { 2561 LValueBaseInfo PointeeBaseInfo; 2562 TBAAAccessInfo PointeeTBAAInfo; 2563 Address PointeeAddr = EmitLoadOfReference(RefLVal, &PointeeBaseInfo, 2564 &PointeeTBAAInfo); 2565 return MakeAddrLValue(PointeeAddr, RefLVal.getType()->getPointeeType(), 2566 PointeeBaseInfo, PointeeTBAAInfo); 2567 } 2568 2569 Address CodeGenFunction::EmitLoadOfPointer(Address Ptr, 2570 const PointerType *PtrTy, 2571 LValueBaseInfo *BaseInfo, 2572 TBAAAccessInfo *TBAAInfo) { 2573 llvm::Value *Addr = Builder.CreateLoad(Ptr); 2574 return Address(Addr, ConvertTypeForMem(PtrTy->getPointeeType()), 2575 CGM.getNaturalTypeAlignment(PtrTy->getPointeeType(), BaseInfo, 2576 TBAAInfo, 2577 /*forPointeeType=*/true)); 2578 } 2579 2580 LValue CodeGenFunction::EmitLoadOfPointerLValue(Address PtrAddr, 2581 const PointerType *PtrTy) { 2582 LValueBaseInfo BaseInfo; 2583 TBAAAccessInfo TBAAInfo; 2584 Address Addr = EmitLoadOfPointer(PtrAddr, PtrTy, &BaseInfo, &TBAAInfo); 2585 return MakeAddrLValue(Addr, PtrTy->getPointeeType(), BaseInfo, TBAAInfo); 2586 } 2587 2588 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF, 2589 const Expr *E, const VarDecl *VD) { 2590 QualType T = E->getType(); 2591 2592 // If it's thread_local, emit a call to its wrapper function instead. 2593 if (VD->getTLSKind() == VarDecl::TLS_Dynamic && 2594 CGF.CGM.getCXXABI().usesThreadWrapperFunction(VD)) 2595 return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T); 2596 // Check if the variable is marked as declare target with link clause in 2597 // device codegen. 2598 if (CGF.getLangOpts().OpenMPIsTargetDevice) { 2599 Address Addr = emitDeclTargetVarDeclLValue(CGF, VD, T); 2600 if (Addr.isValid()) 2601 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl); 2602 } 2603 2604 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD); 2605 2606 if (VD->getTLSKind() != VarDecl::TLS_None) 2607 V = CGF.Builder.CreateThreadLocalAddress(V); 2608 2609 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType()); 2610 CharUnits Alignment = CGF.getContext().getDeclAlign(VD); 2611 Address Addr(V, RealVarTy, Alignment); 2612 // Emit reference to the private copy of the variable if it is an OpenMP 2613 // threadprivate variable. 2614 if (CGF.getLangOpts().OpenMP && !CGF.getLangOpts().OpenMPSimd && 2615 VD->hasAttr<OMPThreadPrivateDeclAttr>()) { 2616 return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy, 2617 E->getExprLoc()); 2618 } 2619 LValue LV = VD->getType()->isReferenceType() ? 2620 CGF.EmitLoadOfReferenceLValue(Addr, VD->getType(), 2621 AlignmentSource::Decl) : 2622 CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl); 2623 setObjCGCLValueClass(CGF.getContext(), E, LV); 2624 return LV; 2625 } 2626 2627 static llvm::Constant *EmitFunctionDeclPointer(CodeGenModule &CGM, 2628 GlobalDecl GD) { 2629 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 2630 if (FD->hasAttr<WeakRefAttr>()) { 2631 ConstantAddress aliasee = CGM.GetWeakRefReference(FD); 2632 return aliasee.getPointer(); 2633 } 2634 2635 llvm::Constant *V = CGM.GetAddrOfFunction(GD); 2636 return V; 2637 } 2638 2639 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF, const Expr *E, 2640 GlobalDecl GD) { 2641 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 2642 llvm::Value *V = EmitFunctionDeclPointer(CGF.CGM, GD); 2643 CharUnits Alignment = CGF.getContext().getDeclAlign(FD); 2644 return CGF.MakeAddrLValue(V, E->getType(), Alignment, 2645 AlignmentSource::Decl); 2646 } 2647 2648 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD, 2649 llvm::Value *ThisValue) { 2650 2651 return CGF.EmitLValueForLambdaField(FD, ThisValue); 2652 } 2653 2654 /// Named Registers are named metadata pointing to the register name 2655 /// which will be read from/written to as an argument to the intrinsic 2656 /// @llvm.read/write_register. 2657 /// So far, only the name is being passed down, but other options such as 2658 /// register type, allocation type or even optimization options could be 2659 /// passed down via the metadata node. 2660 static LValue EmitGlobalNamedRegister(const VarDecl *VD, CodeGenModule &CGM) { 2661 SmallString<64> Name("llvm.named.register."); 2662 AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>(); 2663 assert(Asm->getLabel().size() < 64-Name.size() && 2664 "Register name too big"); 2665 Name.append(Asm->getLabel()); 2666 llvm::NamedMDNode *M = 2667 CGM.getModule().getOrInsertNamedMetadata(Name); 2668 if (M->getNumOperands() == 0) { 2669 llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(), 2670 Asm->getLabel()); 2671 llvm::Metadata *Ops[] = {Str}; 2672 M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops)); 2673 } 2674 2675 CharUnits Alignment = CGM.getContext().getDeclAlign(VD); 2676 2677 llvm::Value *Ptr = 2678 llvm::MetadataAsValue::get(CGM.getLLVMContext(), M->getOperand(0)); 2679 return LValue::MakeGlobalReg(Ptr, Alignment, VD->getType()); 2680 } 2681 2682 /// Determine whether we can emit a reference to \p VD from the current 2683 /// context, despite not necessarily having seen an odr-use of the variable in 2684 /// this context. 2685 static bool canEmitSpuriousReferenceToVariable(CodeGenFunction &CGF, 2686 const DeclRefExpr *E, 2687 const VarDecl *VD) { 2688 // For a variable declared in an enclosing scope, do not emit a spurious 2689 // reference even if we have a capture, as that will emit an unwarranted 2690 // reference to our capture state, and will likely generate worse code than 2691 // emitting a local copy. 2692 if (E->refersToEnclosingVariableOrCapture()) 2693 return false; 2694 2695 // For a local declaration declared in this function, we can always reference 2696 // it even if we don't have an odr-use. 2697 if (VD->hasLocalStorage()) { 2698 return VD->getDeclContext() == 2699 dyn_cast_or_null<DeclContext>(CGF.CurCodeDecl); 2700 } 2701 2702 // For a global declaration, we can emit a reference to it if we know 2703 // for sure that we are able to emit a definition of it. 2704 VD = VD->getDefinition(CGF.getContext()); 2705 if (!VD) 2706 return false; 2707 2708 // Don't emit a spurious reference if it might be to a variable that only 2709 // exists on a different device / target. 2710 // FIXME: This is unnecessarily broad. Check whether this would actually be a 2711 // cross-target reference. 2712 if (CGF.getLangOpts().OpenMP || CGF.getLangOpts().CUDA || 2713 CGF.getLangOpts().OpenCL) { 2714 return false; 2715 } 2716 2717 // We can emit a spurious reference only if the linkage implies that we'll 2718 // be emitting a non-interposable symbol that will be retained until link 2719 // time. 2720 switch (CGF.CGM.getLLVMLinkageVarDefinition(VD)) { 2721 case llvm::GlobalValue::ExternalLinkage: 2722 case llvm::GlobalValue::LinkOnceODRLinkage: 2723 case llvm::GlobalValue::WeakODRLinkage: 2724 case llvm::GlobalValue::InternalLinkage: 2725 case llvm::GlobalValue::PrivateLinkage: 2726 return true; 2727 default: 2728 return false; 2729 } 2730 } 2731 2732 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) { 2733 const NamedDecl *ND = E->getDecl(); 2734 QualType T = E->getType(); 2735 2736 assert(E->isNonOdrUse() != NOUR_Unevaluated && 2737 "should not emit an unevaluated operand"); 2738 2739 if (const auto *VD = dyn_cast<VarDecl>(ND)) { 2740 // Global Named registers access via intrinsics only 2741 if (VD->getStorageClass() == SC_Register && 2742 VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl()) 2743 return EmitGlobalNamedRegister(VD, CGM); 2744 2745 // If this DeclRefExpr does not constitute an odr-use of the variable, 2746 // we're not permitted to emit a reference to it in general, and it might 2747 // not be captured if capture would be necessary for a use. Emit the 2748 // constant value directly instead. 2749 if (E->isNonOdrUse() == NOUR_Constant && 2750 (VD->getType()->isReferenceType() || 2751 !canEmitSpuriousReferenceToVariable(*this, E, VD))) { 2752 VD->getAnyInitializer(VD); 2753 llvm::Constant *Val = ConstantEmitter(*this).emitAbstract( 2754 E->getLocation(), *VD->evaluateValue(), VD->getType()); 2755 assert(Val && "failed to emit constant expression"); 2756 2757 Address Addr = Address::invalid(); 2758 if (!VD->getType()->isReferenceType()) { 2759 // Spill the constant value to a global. 2760 Addr = CGM.createUnnamedGlobalFrom(*VD, Val, 2761 getContext().getDeclAlign(VD)); 2762 llvm::Type *VarTy = getTypes().ConvertTypeForMem(VD->getType()); 2763 auto *PTy = llvm::PointerType::get( 2764 VarTy, getTypes().getTargetAddressSpace(VD->getType())); 2765 Addr = Builder.CreatePointerBitCastOrAddrSpaceCast(Addr, PTy, VarTy); 2766 } else { 2767 // Should we be using the alignment of the constant pointer we emitted? 2768 CharUnits Alignment = 2769 CGM.getNaturalTypeAlignment(E->getType(), 2770 /* BaseInfo= */ nullptr, 2771 /* TBAAInfo= */ nullptr, 2772 /* forPointeeType= */ true); 2773 Addr = Address(Val, ConvertTypeForMem(E->getType()), Alignment); 2774 } 2775 return MakeAddrLValue(Addr, T, AlignmentSource::Decl); 2776 } 2777 2778 // FIXME: Handle other kinds of non-odr-use DeclRefExprs. 2779 2780 // Check for captured variables. 2781 if (E->refersToEnclosingVariableOrCapture()) { 2782 VD = VD->getCanonicalDecl(); 2783 if (auto *FD = LambdaCaptureFields.lookup(VD)) 2784 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue); 2785 if (CapturedStmtInfo) { 2786 auto I = LocalDeclMap.find(VD); 2787 if (I != LocalDeclMap.end()) { 2788 LValue CapLVal; 2789 if (VD->getType()->isReferenceType()) 2790 CapLVal = EmitLoadOfReferenceLValue(I->second, VD->getType(), 2791 AlignmentSource::Decl); 2792 else 2793 CapLVal = MakeAddrLValue(I->second, T); 2794 // Mark lvalue as nontemporal if the variable is marked as nontemporal 2795 // in simd context. 2796 if (getLangOpts().OpenMP && 2797 CGM.getOpenMPRuntime().isNontemporalDecl(VD)) 2798 CapLVal.setNontemporal(/*Value=*/true); 2799 return CapLVal; 2800 } 2801 LValue CapLVal = 2802 EmitCapturedFieldLValue(*this, CapturedStmtInfo->lookup(VD), 2803 CapturedStmtInfo->getContextValue()); 2804 Address LValueAddress = CapLVal.getAddress(*this); 2805 CapLVal = MakeAddrLValue( 2806 Address(LValueAddress.getPointer(), LValueAddress.getElementType(), 2807 getContext().getDeclAlign(VD)), 2808 CapLVal.getType(), LValueBaseInfo(AlignmentSource::Decl), 2809 CapLVal.getTBAAInfo()); 2810 // Mark lvalue as nontemporal if the variable is marked as nontemporal 2811 // in simd context. 2812 if (getLangOpts().OpenMP && 2813 CGM.getOpenMPRuntime().isNontemporalDecl(VD)) 2814 CapLVal.setNontemporal(/*Value=*/true); 2815 return CapLVal; 2816 } 2817 2818 assert(isa<BlockDecl>(CurCodeDecl)); 2819 Address addr = GetAddrOfBlockDecl(VD); 2820 return MakeAddrLValue(addr, T, AlignmentSource::Decl); 2821 } 2822 } 2823 2824 // FIXME: We should be able to assert this for FunctionDecls as well! 2825 // FIXME: We should be able to assert this for all DeclRefExprs, not just 2826 // those with a valid source location. 2827 assert((ND->isUsed(false) || !isa<VarDecl>(ND) || E->isNonOdrUse() || 2828 !E->getLocation().isValid()) && 2829 "Should not use decl without marking it used!"); 2830 2831 if (ND->hasAttr<WeakRefAttr>()) { 2832 const auto *VD = cast<ValueDecl>(ND); 2833 ConstantAddress Aliasee = CGM.GetWeakRefReference(VD); 2834 return MakeAddrLValue(Aliasee, T, AlignmentSource::Decl); 2835 } 2836 2837 if (const auto *VD = dyn_cast<VarDecl>(ND)) { 2838 // Check if this is a global variable. 2839 if (VD->hasLinkage() || VD->isStaticDataMember()) 2840 return EmitGlobalVarDeclLValue(*this, E, VD); 2841 2842 Address addr = Address::invalid(); 2843 2844 // The variable should generally be present in the local decl map. 2845 auto iter = LocalDeclMap.find(VD); 2846 if (iter != LocalDeclMap.end()) { 2847 addr = iter->second; 2848 2849 // Otherwise, it might be static local we haven't emitted yet for 2850 // some reason; most likely, because it's in an outer function. 2851 } else if (VD->isStaticLocal()) { 2852 llvm::Constant *var = CGM.getOrCreateStaticVarDecl( 2853 *VD, CGM.getLLVMLinkageVarDefinition(VD)); 2854 addr = Address( 2855 var, ConvertTypeForMem(VD->getType()), getContext().getDeclAlign(VD)); 2856 2857 // No other cases for now. 2858 } else { 2859 llvm_unreachable("DeclRefExpr for Decl not entered in LocalDeclMap?"); 2860 } 2861 2862 // Handle threadlocal function locals. 2863 if (VD->getTLSKind() != VarDecl::TLS_None) 2864 addr = addr.withPointer( 2865 Builder.CreateThreadLocalAddress(addr.getPointer()), NotKnownNonNull); 2866 2867 // Check for OpenMP threadprivate variables. 2868 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd && 2869 VD->hasAttr<OMPThreadPrivateDeclAttr>()) { 2870 return EmitThreadPrivateVarDeclLValue( 2871 *this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()), 2872 E->getExprLoc()); 2873 } 2874 2875 // Drill into block byref variables. 2876 bool isBlockByref = VD->isEscapingByref(); 2877 if (isBlockByref) { 2878 addr = emitBlockByrefAddress(addr, VD); 2879 } 2880 2881 // Drill into reference types. 2882 LValue LV = VD->getType()->isReferenceType() ? 2883 EmitLoadOfReferenceLValue(addr, VD->getType(), AlignmentSource::Decl) : 2884 MakeAddrLValue(addr, T, AlignmentSource::Decl); 2885 2886 bool isLocalStorage = VD->hasLocalStorage(); 2887 2888 bool NonGCable = isLocalStorage && 2889 !VD->getType()->isReferenceType() && 2890 !isBlockByref; 2891 if (NonGCable) { 2892 LV.getQuals().removeObjCGCAttr(); 2893 LV.setNonGC(true); 2894 } 2895 2896 bool isImpreciseLifetime = 2897 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>()); 2898 if (isImpreciseLifetime) 2899 LV.setARCPreciseLifetime(ARCImpreciseLifetime); 2900 setObjCGCLValueClass(getContext(), E, LV); 2901 return LV; 2902 } 2903 2904 if (const auto *FD = dyn_cast<FunctionDecl>(ND)) { 2905 LValue LV = EmitFunctionDeclLValue(*this, E, FD); 2906 2907 // Emit debuginfo for the function declaration if the target wants to. 2908 if (getContext().getTargetInfo().allowDebugInfoForExternalRef()) { 2909 if (CGDebugInfo *DI = CGM.getModuleDebugInfo()) { 2910 auto *Fn = 2911 cast<llvm::Function>(LV.getPointer(*this)->stripPointerCasts()); 2912 if (!Fn->getSubprogram()) 2913 DI->EmitFunctionDecl(FD, FD->getLocation(), T, Fn); 2914 } 2915 } 2916 2917 return LV; 2918 } 2919 2920 // FIXME: While we're emitting a binding from an enclosing scope, all other 2921 // DeclRefExprs we see should be implicitly treated as if they also refer to 2922 // an enclosing scope. 2923 if (const auto *BD = dyn_cast<BindingDecl>(ND)) { 2924 if (E->refersToEnclosingVariableOrCapture()) { 2925 auto *FD = LambdaCaptureFields.lookup(BD); 2926 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue); 2927 } 2928 return EmitLValue(BD->getBinding()); 2929 } 2930 2931 // We can form DeclRefExprs naming GUID declarations when reconstituting 2932 // non-type template parameters into expressions. 2933 if (const auto *GD = dyn_cast<MSGuidDecl>(ND)) 2934 return MakeAddrLValue(CGM.GetAddrOfMSGuidDecl(GD), T, 2935 AlignmentSource::Decl); 2936 2937 if (const auto *TPO = dyn_cast<TemplateParamObjectDecl>(ND)) { 2938 auto ATPO = CGM.GetAddrOfTemplateParamObject(TPO); 2939 auto AS = getLangASFromTargetAS(ATPO.getAddressSpace()); 2940 2941 if (AS != T.getAddressSpace()) { 2942 auto TargetAS = getContext().getTargetAddressSpace(T.getAddressSpace()); 2943 auto PtrTy = ATPO.getElementType()->getPointerTo(TargetAS); 2944 auto ASC = getTargetHooks().performAddrSpaceCast( 2945 CGM, ATPO.getPointer(), AS, T.getAddressSpace(), PtrTy); 2946 ATPO = ConstantAddress(ASC, ATPO.getElementType(), ATPO.getAlignment()); 2947 } 2948 2949 return MakeAddrLValue(ATPO, T, AlignmentSource::Decl); 2950 } 2951 2952 llvm_unreachable("Unhandled DeclRefExpr"); 2953 } 2954 2955 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) { 2956 // __extension__ doesn't affect lvalue-ness. 2957 if (E->getOpcode() == UO_Extension) 2958 return EmitLValue(E->getSubExpr()); 2959 2960 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType()); 2961 switch (E->getOpcode()) { 2962 default: llvm_unreachable("Unknown unary operator lvalue!"); 2963 case UO_Deref: { 2964 QualType T = E->getSubExpr()->getType()->getPointeeType(); 2965 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type"); 2966 2967 LValueBaseInfo BaseInfo; 2968 TBAAAccessInfo TBAAInfo; 2969 Address Addr = EmitPointerWithAlignment(E->getSubExpr(), &BaseInfo, 2970 &TBAAInfo); 2971 LValue LV = MakeAddrLValue(Addr, T, BaseInfo, TBAAInfo); 2972 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace()); 2973 2974 // We should not generate __weak write barrier on indirect reference 2975 // of a pointer to object; as in void foo (__weak id *param); *param = 0; 2976 // But, we continue to generate __strong write barrier on indirect write 2977 // into a pointer to object. 2978 if (getLangOpts().ObjC && 2979 getLangOpts().getGC() != LangOptions::NonGC && 2980 LV.isObjCWeak()) 2981 LV.setNonGC(!E->isOBJCGCCandidate(getContext())); 2982 return LV; 2983 } 2984 case UO_Real: 2985 case UO_Imag: { 2986 LValue LV = EmitLValue(E->getSubExpr()); 2987 assert(LV.isSimple() && "real/imag on non-ordinary l-value"); 2988 2989 // __real is valid on scalars. This is a faster way of testing that. 2990 // __imag can only produce an rvalue on scalars. 2991 if (E->getOpcode() == UO_Real && 2992 !LV.getAddress(*this).getElementType()->isStructTy()) { 2993 assert(E->getSubExpr()->getType()->isArithmeticType()); 2994 return LV; 2995 } 2996 2997 QualType T = ExprTy->castAs<ComplexType>()->getElementType(); 2998 2999 Address Component = 3000 (E->getOpcode() == UO_Real 3001 ? emitAddrOfRealComponent(LV.getAddress(*this), LV.getType()) 3002 : emitAddrOfImagComponent(LV.getAddress(*this), LV.getType())); 3003 LValue ElemLV = MakeAddrLValue(Component, T, LV.getBaseInfo(), 3004 CGM.getTBAAInfoForSubobject(LV, T)); 3005 ElemLV.getQuals().addQualifiers(LV.getQuals()); 3006 return ElemLV; 3007 } 3008 case UO_PreInc: 3009 case UO_PreDec: { 3010 LValue LV = EmitLValue(E->getSubExpr()); 3011 bool isInc = E->getOpcode() == UO_PreInc; 3012 3013 if (E->getType()->isAnyComplexType()) 3014 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/); 3015 else 3016 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/); 3017 return LV; 3018 } 3019 } 3020 } 3021 3022 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) { 3023 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E), 3024 E->getType(), AlignmentSource::Decl); 3025 } 3026 3027 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) { 3028 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E), 3029 E->getType(), AlignmentSource::Decl); 3030 } 3031 3032 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) { 3033 auto SL = E->getFunctionName(); 3034 assert(SL != nullptr && "No StringLiteral name in PredefinedExpr"); 3035 StringRef FnName = CurFn->getName(); 3036 if (FnName.starts_with("\01")) 3037 FnName = FnName.substr(1); 3038 StringRef NameItems[] = { 3039 PredefinedExpr::getIdentKindName(E->getIdentKind()), FnName}; 3040 std::string GVName = llvm::join(NameItems, NameItems + 2, "."); 3041 if (auto *BD = dyn_cast_or_null<BlockDecl>(CurCodeDecl)) { 3042 std::string Name = std::string(SL->getString()); 3043 if (!Name.empty()) { 3044 unsigned Discriminator = 3045 CGM.getCXXABI().getMangleContext().getBlockId(BD, true); 3046 if (Discriminator) 3047 Name += "_" + Twine(Discriminator + 1).str(); 3048 auto C = CGM.GetAddrOfConstantCString(Name, GVName.c_str()); 3049 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl); 3050 } else { 3051 auto C = 3052 CGM.GetAddrOfConstantCString(std::string(FnName), GVName.c_str()); 3053 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl); 3054 } 3055 } 3056 auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName); 3057 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl); 3058 } 3059 3060 /// Emit a type description suitable for use by a runtime sanitizer library. The 3061 /// format of a type descriptor is 3062 /// 3063 /// \code 3064 /// { i16 TypeKind, i16 TypeInfo } 3065 /// \endcode 3066 /// 3067 /// followed by an array of i8 containing the type name. TypeKind is 0 for an 3068 /// integer, 1 for a floating point value, and -1 for anything else. 3069 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) { 3070 // Only emit each type's descriptor once. 3071 if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T)) 3072 return C; 3073 3074 uint16_t TypeKind = -1; 3075 uint16_t TypeInfo = 0; 3076 3077 if (T->isIntegerType()) { 3078 TypeKind = 0; 3079 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) | 3080 (T->isSignedIntegerType() ? 1 : 0); 3081 } else if (T->isFloatingType()) { 3082 TypeKind = 1; 3083 TypeInfo = getContext().getTypeSize(T); 3084 } 3085 3086 // Format the type name as if for a diagnostic, including quotes and 3087 // optionally an 'aka'. 3088 SmallString<32> Buffer; 3089 CGM.getDiags().ConvertArgToString( 3090 DiagnosticsEngine::ak_qualtype, (intptr_t)T.getAsOpaquePtr(), StringRef(), 3091 StringRef(), std::nullopt, Buffer, std::nullopt); 3092 3093 llvm::Constant *Components[] = { 3094 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo), 3095 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer) 3096 }; 3097 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components); 3098 3099 auto *GV = new llvm::GlobalVariable( 3100 CGM.getModule(), Descriptor->getType(), 3101 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor); 3102 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3103 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(GV); 3104 3105 // Remember the descriptor for this type. 3106 CGM.setTypeDescriptorInMap(T, GV); 3107 3108 return GV; 3109 } 3110 3111 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) { 3112 llvm::Type *TargetTy = IntPtrTy; 3113 3114 if (V->getType() == TargetTy) 3115 return V; 3116 3117 // Floating-point types which fit into intptr_t are bitcast to integers 3118 // and then passed directly (after zero-extension, if necessary). 3119 if (V->getType()->isFloatingPointTy()) { 3120 unsigned Bits = V->getType()->getPrimitiveSizeInBits().getFixedValue(); 3121 if (Bits <= TargetTy->getIntegerBitWidth()) 3122 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(), 3123 Bits)); 3124 } 3125 3126 // Integers which fit in intptr_t are zero-extended and passed directly. 3127 if (V->getType()->isIntegerTy() && 3128 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth()) 3129 return Builder.CreateZExt(V, TargetTy); 3130 3131 // Pointers are passed directly, everything else is passed by address. 3132 if (!V->getType()->isPointerTy()) { 3133 Address Ptr = CreateDefaultAlignTempAlloca(V->getType()); 3134 Builder.CreateStore(V, Ptr); 3135 V = Ptr.getPointer(); 3136 } 3137 return Builder.CreatePtrToInt(V, TargetTy); 3138 } 3139 3140 /// Emit a representation of a SourceLocation for passing to a handler 3141 /// in a sanitizer runtime library. The format for this data is: 3142 /// \code 3143 /// struct SourceLocation { 3144 /// const char *Filename; 3145 /// int32_t Line, Column; 3146 /// }; 3147 /// \endcode 3148 /// For an invalid SourceLocation, the Filename pointer is null. 3149 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) { 3150 llvm::Constant *Filename; 3151 int Line, Column; 3152 3153 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc); 3154 if (PLoc.isValid()) { 3155 StringRef FilenameString = PLoc.getFilename(); 3156 3157 int PathComponentsToStrip = 3158 CGM.getCodeGenOpts().EmitCheckPathComponentsToStrip; 3159 if (PathComponentsToStrip < 0) { 3160 assert(PathComponentsToStrip != INT_MIN); 3161 int PathComponentsToKeep = -PathComponentsToStrip; 3162 auto I = llvm::sys::path::rbegin(FilenameString); 3163 auto E = llvm::sys::path::rend(FilenameString); 3164 while (I != E && --PathComponentsToKeep) 3165 ++I; 3166 3167 FilenameString = FilenameString.substr(I - E); 3168 } else if (PathComponentsToStrip > 0) { 3169 auto I = llvm::sys::path::begin(FilenameString); 3170 auto E = llvm::sys::path::end(FilenameString); 3171 while (I != E && PathComponentsToStrip--) 3172 ++I; 3173 3174 if (I != E) 3175 FilenameString = 3176 FilenameString.substr(I - llvm::sys::path::begin(FilenameString)); 3177 else 3178 FilenameString = llvm::sys::path::filename(FilenameString); 3179 } 3180 3181 auto FilenameGV = 3182 CGM.GetAddrOfConstantCString(std::string(FilenameString), ".src"); 3183 CGM.getSanitizerMetadata()->disableSanitizerForGlobal( 3184 cast<llvm::GlobalVariable>( 3185 FilenameGV.getPointer()->stripPointerCasts())); 3186 Filename = FilenameGV.getPointer(); 3187 Line = PLoc.getLine(); 3188 Column = PLoc.getColumn(); 3189 } else { 3190 Filename = llvm::Constant::getNullValue(Int8PtrTy); 3191 Line = Column = 0; 3192 } 3193 3194 llvm::Constant *Data[] = {Filename, Builder.getInt32(Line), 3195 Builder.getInt32(Column)}; 3196 3197 return llvm::ConstantStruct::getAnon(Data); 3198 } 3199 3200 namespace { 3201 /// Specify under what conditions this check can be recovered 3202 enum class CheckRecoverableKind { 3203 /// Always terminate program execution if this check fails. 3204 Unrecoverable, 3205 /// Check supports recovering, runtime has both fatal (noreturn) and 3206 /// non-fatal handlers for this check. 3207 Recoverable, 3208 /// Runtime conditionally aborts, always need to support recovery. 3209 AlwaysRecoverable 3210 }; 3211 } 3212 3213 static CheckRecoverableKind getRecoverableKind(SanitizerMask Kind) { 3214 assert(Kind.countPopulation() == 1); 3215 if (Kind == SanitizerKind::Vptr) 3216 return CheckRecoverableKind::AlwaysRecoverable; 3217 else if (Kind == SanitizerKind::Return || Kind == SanitizerKind::Unreachable) 3218 return CheckRecoverableKind::Unrecoverable; 3219 else 3220 return CheckRecoverableKind::Recoverable; 3221 } 3222 3223 namespace { 3224 struct SanitizerHandlerInfo { 3225 char const *const Name; 3226 unsigned Version; 3227 }; 3228 } 3229 3230 const SanitizerHandlerInfo SanitizerHandlers[] = { 3231 #define SANITIZER_CHECK(Enum, Name, Version) {#Name, Version}, 3232 LIST_SANITIZER_CHECKS 3233 #undef SANITIZER_CHECK 3234 }; 3235 3236 static void emitCheckHandlerCall(CodeGenFunction &CGF, 3237 llvm::FunctionType *FnType, 3238 ArrayRef<llvm::Value *> FnArgs, 3239 SanitizerHandler CheckHandler, 3240 CheckRecoverableKind RecoverKind, bool IsFatal, 3241 llvm::BasicBlock *ContBB) { 3242 assert(IsFatal || RecoverKind != CheckRecoverableKind::Unrecoverable); 3243 std::optional<ApplyDebugLocation> DL; 3244 if (!CGF.Builder.getCurrentDebugLocation()) { 3245 // Ensure that the call has at least an artificial debug location. 3246 DL.emplace(CGF, SourceLocation()); 3247 } 3248 bool NeedsAbortSuffix = 3249 IsFatal && RecoverKind != CheckRecoverableKind::Unrecoverable; 3250 bool MinimalRuntime = CGF.CGM.getCodeGenOpts().SanitizeMinimalRuntime; 3251 const SanitizerHandlerInfo &CheckInfo = SanitizerHandlers[CheckHandler]; 3252 const StringRef CheckName = CheckInfo.Name; 3253 std::string FnName = "__ubsan_handle_" + CheckName.str(); 3254 if (CheckInfo.Version && !MinimalRuntime) 3255 FnName += "_v" + llvm::utostr(CheckInfo.Version); 3256 if (MinimalRuntime) 3257 FnName += "_minimal"; 3258 if (NeedsAbortSuffix) 3259 FnName += "_abort"; 3260 bool MayReturn = 3261 !IsFatal || RecoverKind == CheckRecoverableKind::AlwaysRecoverable; 3262 3263 llvm::AttrBuilder B(CGF.getLLVMContext()); 3264 if (!MayReturn) { 3265 B.addAttribute(llvm::Attribute::NoReturn) 3266 .addAttribute(llvm::Attribute::NoUnwind); 3267 } 3268 B.addUWTableAttr(llvm::UWTableKind::Default); 3269 3270 llvm::FunctionCallee Fn = CGF.CGM.CreateRuntimeFunction( 3271 FnType, FnName, 3272 llvm::AttributeList::get(CGF.getLLVMContext(), 3273 llvm::AttributeList::FunctionIndex, B), 3274 /*Local=*/true); 3275 llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs); 3276 if (!MayReturn) { 3277 HandlerCall->setDoesNotReturn(); 3278 CGF.Builder.CreateUnreachable(); 3279 } else { 3280 CGF.Builder.CreateBr(ContBB); 3281 } 3282 } 3283 3284 void CodeGenFunction::EmitCheck( 3285 ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked, 3286 SanitizerHandler CheckHandler, ArrayRef<llvm::Constant *> StaticArgs, 3287 ArrayRef<llvm::Value *> DynamicArgs) { 3288 assert(IsSanitizerScope); 3289 assert(Checked.size() > 0); 3290 assert(CheckHandler >= 0 && 3291 size_t(CheckHandler) < std::size(SanitizerHandlers)); 3292 const StringRef CheckName = SanitizerHandlers[CheckHandler].Name; 3293 3294 llvm::Value *FatalCond = nullptr; 3295 llvm::Value *RecoverableCond = nullptr; 3296 llvm::Value *TrapCond = nullptr; 3297 for (int i = 0, n = Checked.size(); i < n; ++i) { 3298 llvm::Value *Check = Checked[i].first; 3299 // -fsanitize-trap= overrides -fsanitize-recover=. 3300 llvm::Value *&Cond = 3301 CGM.getCodeGenOpts().SanitizeTrap.has(Checked[i].second) 3302 ? TrapCond 3303 : CGM.getCodeGenOpts().SanitizeRecover.has(Checked[i].second) 3304 ? RecoverableCond 3305 : FatalCond; 3306 Cond = Cond ? Builder.CreateAnd(Cond, Check) : Check; 3307 } 3308 3309 if (TrapCond) 3310 EmitTrapCheck(TrapCond, CheckHandler); 3311 if (!FatalCond && !RecoverableCond) 3312 return; 3313 3314 llvm::Value *JointCond; 3315 if (FatalCond && RecoverableCond) 3316 JointCond = Builder.CreateAnd(FatalCond, RecoverableCond); 3317 else 3318 JointCond = FatalCond ? FatalCond : RecoverableCond; 3319 assert(JointCond); 3320 3321 CheckRecoverableKind RecoverKind = getRecoverableKind(Checked[0].second); 3322 assert(SanOpts.has(Checked[0].second)); 3323 #ifndef NDEBUG 3324 for (int i = 1, n = Checked.size(); i < n; ++i) { 3325 assert(RecoverKind == getRecoverableKind(Checked[i].second) && 3326 "All recoverable kinds in a single check must be same!"); 3327 assert(SanOpts.has(Checked[i].second)); 3328 } 3329 #endif 3330 3331 llvm::BasicBlock *Cont = createBasicBlock("cont"); 3332 llvm::BasicBlock *Handlers = createBasicBlock("handler." + CheckName); 3333 llvm::Instruction *Branch = Builder.CreateCondBr(JointCond, Cont, Handlers); 3334 // Give hint that we very much don't expect to execute the handler 3335 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp 3336 llvm::MDBuilder MDHelper(getLLVMContext()); 3337 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1); 3338 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node); 3339 EmitBlock(Handlers); 3340 3341 // Handler functions take an i8* pointing to the (handler-specific) static 3342 // information block, followed by a sequence of intptr_t arguments 3343 // representing operand values. 3344 SmallVector<llvm::Value *, 4> Args; 3345 SmallVector<llvm::Type *, 4> ArgTypes; 3346 if (!CGM.getCodeGenOpts().SanitizeMinimalRuntime) { 3347 Args.reserve(DynamicArgs.size() + 1); 3348 ArgTypes.reserve(DynamicArgs.size() + 1); 3349 3350 // Emit handler arguments and create handler function type. 3351 if (!StaticArgs.empty()) { 3352 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs); 3353 auto *InfoPtr = new llvm::GlobalVariable( 3354 CGM.getModule(), Info->getType(), false, 3355 llvm::GlobalVariable::PrivateLinkage, Info, "", nullptr, 3356 llvm::GlobalVariable::NotThreadLocal, 3357 CGM.getDataLayout().getDefaultGlobalsAddressSpace()); 3358 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3359 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr); 3360 Args.push_back(InfoPtr); 3361 ArgTypes.push_back(Args.back()->getType()); 3362 } 3363 3364 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) { 3365 Args.push_back(EmitCheckValue(DynamicArgs[i])); 3366 ArgTypes.push_back(IntPtrTy); 3367 } 3368 } 3369 3370 llvm::FunctionType *FnType = 3371 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false); 3372 3373 if (!FatalCond || !RecoverableCond) { 3374 // Simple case: we need to generate a single handler call, either 3375 // fatal, or non-fatal. 3376 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, 3377 (FatalCond != nullptr), Cont); 3378 } else { 3379 // Emit two handler calls: first one for set of unrecoverable checks, 3380 // another one for recoverable. 3381 llvm::BasicBlock *NonFatalHandlerBB = 3382 createBasicBlock("non_fatal." + CheckName); 3383 llvm::BasicBlock *FatalHandlerBB = createBasicBlock("fatal." + CheckName); 3384 Builder.CreateCondBr(FatalCond, NonFatalHandlerBB, FatalHandlerBB); 3385 EmitBlock(FatalHandlerBB); 3386 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, true, 3387 NonFatalHandlerBB); 3388 EmitBlock(NonFatalHandlerBB); 3389 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, false, 3390 Cont); 3391 } 3392 3393 EmitBlock(Cont); 3394 } 3395 3396 void CodeGenFunction::EmitCfiSlowPathCheck( 3397 SanitizerMask Kind, llvm::Value *Cond, llvm::ConstantInt *TypeId, 3398 llvm::Value *Ptr, ArrayRef<llvm::Constant *> StaticArgs) { 3399 llvm::BasicBlock *Cont = createBasicBlock("cfi.cont"); 3400 3401 llvm::BasicBlock *CheckBB = createBasicBlock("cfi.slowpath"); 3402 llvm::BranchInst *BI = Builder.CreateCondBr(Cond, Cont, CheckBB); 3403 3404 llvm::MDBuilder MDHelper(getLLVMContext()); 3405 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1); 3406 BI->setMetadata(llvm::LLVMContext::MD_prof, Node); 3407 3408 EmitBlock(CheckBB); 3409 3410 bool WithDiag = !CGM.getCodeGenOpts().SanitizeTrap.has(Kind); 3411 3412 llvm::CallInst *CheckCall; 3413 llvm::FunctionCallee SlowPathFn; 3414 if (WithDiag) { 3415 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs); 3416 auto *InfoPtr = 3417 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false, 3418 llvm::GlobalVariable::PrivateLinkage, Info); 3419 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3420 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr); 3421 3422 SlowPathFn = CGM.getModule().getOrInsertFunction( 3423 "__cfi_slowpath_diag", 3424 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, 3425 false)); 3426 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr, InfoPtr}); 3427 } else { 3428 SlowPathFn = CGM.getModule().getOrInsertFunction( 3429 "__cfi_slowpath", 3430 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy}, false)); 3431 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr}); 3432 } 3433 3434 CGM.setDSOLocal( 3435 cast<llvm::GlobalValue>(SlowPathFn.getCallee()->stripPointerCasts())); 3436 CheckCall->setDoesNotThrow(); 3437 3438 EmitBlock(Cont); 3439 } 3440 3441 // Emit a stub for __cfi_check function so that the linker knows about this 3442 // symbol in LTO mode. 3443 void CodeGenFunction::EmitCfiCheckStub() { 3444 llvm::Module *M = &CGM.getModule(); 3445 auto &Ctx = M->getContext(); 3446 llvm::Function *F = llvm::Function::Create( 3447 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, false), 3448 llvm::GlobalValue::WeakAnyLinkage, "__cfi_check", M); 3449 F->setAlignment(llvm::Align(4096)); 3450 CGM.setDSOLocal(F); 3451 llvm::BasicBlock *BB = llvm::BasicBlock::Create(Ctx, "entry", F); 3452 // CrossDSOCFI pass is not executed if there is no executable code. 3453 SmallVector<llvm::Value*> Args{F->getArg(2), F->getArg(1)}; 3454 llvm::CallInst::Create(M->getFunction("__cfi_check_fail"), Args, "", BB); 3455 llvm::ReturnInst::Create(Ctx, nullptr, BB); 3456 } 3457 3458 // This function is basically a switch over the CFI failure kind, which is 3459 // extracted from CFICheckFailData (1st function argument). Each case is either 3460 // llvm.trap or a call to one of the two runtime handlers, based on 3461 // -fsanitize-trap and -fsanitize-recover settings. Default case (invalid 3462 // failure kind) traps, but this should really never happen. CFICheckFailData 3463 // can be nullptr if the calling module has -fsanitize-trap behavior for this 3464 // check kind; in this case __cfi_check_fail traps as well. 3465 void CodeGenFunction::EmitCfiCheckFail() { 3466 SanitizerScope SanScope(this); 3467 FunctionArgList Args; 3468 ImplicitParamDecl ArgData(getContext(), getContext().VoidPtrTy, 3469 ImplicitParamKind::Other); 3470 ImplicitParamDecl ArgAddr(getContext(), getContext().VoidPtrTy, 3471 ImplicitParamKind::Other); 3472 Args.push_back(&ArgData); 3473 Args.push_back(&ArgAddr); 3474 3475 const CGFunctionInfo &FI = 3476 CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, Args); 3477 3478 llvm::Function *F = llvm::Function::Create( 3479 llvm::FunctionType::get(VoidTy, {VoidPtrTy, VoidPtrTy}, false), 3480 llvm::GlobalValue::WeakODRLinkage, "__cfi_check_fail", &CGM.getModule()); 3481 3482 CGM.SetLLVMFunctionAttributes(GlobalDecl(), FI, F, /*IsThunk=*/false); 3483 CGM.SetLLVMFunctionAttributesForDefinition(nullptr, F); 3484 F->setVisibility(llvm::GlobalValue::HiddenVisibility); 3485 3486 StartFunction(GlobalDecl(), CGM.getContext().VoidTy, F, FI, Args, 3487 SourceLocation()); 3488 3489 // This function is not affected by NoSanitizeList. This function does 3490 // not have a source location, but "src:*" would still apply. Revert any 3491 // changes to SanOpts made in StartFunction. 3492 SanOpts = CGM.getLangOpts().Sanitize; 3493 3494 llvm::Value *Data = 3495 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgData), /*Volatile=*/false, 3496 CGM.getContext().VoidPtrTy, ArgData.getLocation()); 3497 llvm::Value *Addr = 3498 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgAddr), /*Volatile=*/false, 3499 CGM.getContext().VoidPtrTy, ArgAddr.getLocation()); 3500 3501 // Data == nullptr means the calling module has trap behaviour for this check. 3502 llvm::Value *DataIsNotNullPtr = 3503 Builder.CreateICmpNE(Data, llvm::ConstantPointerNull::get(Int8PtrTy)); 3504 EmitTrapCheck(DataIsNotNullPtr, SanitizerHandler::CFICheckFail); 3505 3506 llvm::StructType *SourceLocationTy = 3507 llvm::StructType::get(VoidPtrTy, Int32Ty, Int32Ty); 3508 llvm::StructType *CfiCheckFailDataTy = 3509 llvm::StructType::get(Int8Ty, SourceLocationTy, VoidPtrTy); 3510 3511 llvm::Value *V = Builder.CreateConstGEP2_32( 3512 CfiCheckFailDataTy, 3513 Builder.CreatePointerCast(Data, CfiCheckFailDataTy->getPointerTo(0)), 0, 3514 0); 3515 3516 Address CheckKindAddr(V, Int8Ty, getIntAlign()); 3517 llvm::Value *CheckKind = Builder.CreateLoad(CheckKindAddr); 3518 3519 llvm::Value *AllVtables = llvm::MetadataAsValue::get( 3520 CGM.getLLVMContext(), 3521 llvm::MDString::get(CGM.getLLVMContext(), "all-vtables")); 3522 llvm::Value *ValidVtable = Builder.CreateZExt( 3523 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::type_test), 3524 {Addr, AllVtables}), 3525 IntPtrTy); 3526 3527 const std::pair<int, SanitizerMask> CheckKinds[] = { 3528 {CFITCK_VCall, SanitizerKind::CFIVCall}, 3529 {CFITCK_NVCall, SanitizerKind::CFINVCall}, 3530 {CFITCK_DerivedCast, SanitizerKind::CFIDerivedCast}, 3531 {CFITCK_UnrelatedCast, SanitizerKind::CFIUnrelatedCast}, 3532 {CFITCK_ICall, SanitizerKind::CFIICall}}; 3533 3534 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 5> Checks; 3535 for (auto CheckKindMaskPair : CheckKinds) { 3536 int Kind = CheckKindMaskPair.first; 3537 SanitizerMask Mask = CheckKindMaskPair.second; 3538 llvm::Value *Cond = 3539 Builder.CreateICmpNE(CheckKind, llvm::ConstantInt::get(Int8Ty, Kind)); 3540 if (CGM.getLangOpts().Sanitize.has(Mask)) 3541 EmitCheck(std::make_pair(Cond, Mask), SanitizerHandler::CFICheckFail, {}, 3542 {Data, Addr, ValidVtable}); 3543 else 3544 EmitTrapCheck(Cond, SanitizerHandler::CFICheckFail); 3545 } 3546 3547 FinishFunction(); 3548 // The only reference to this function will be created during LTO link. 3549 // Make sure it survives until then. 3550 CGM.addUsedGlobal(F); 3551 } 3552 3553 void CodeGenFunction::EmitUnreachable(SourceLocation Loc) { 3554 if (SanOpts.has(SanitizerKind::Unreachable)) { 3555 SanitizerScope SanScope(this); 3556 EmitCheck(std::make_pair(static_cast<llvm::Value *>(Builder.getFalse()), 3557 SanitizerKind::Unreachable), 3558 SanitizerHandler::BuiltinUnreachable, 3559 EmitCheckSourceLocation(Loc), std::nullopt); 3560 } 3561 Builder.CreateUnreachable(); 3562 } 3563 3564 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked, 3565 SanitizerHandler CheckHandlerID) { 3566 llvm::BasicBlock *Cont = createBasicBlock("cont"); 3567 3568 // If we're optimizing, collapse all calls to trap down to just one per 3569 // check-type per function to save on code size. 3570 if (TrapBBs.size() <= CheckHandlerID) 3571 TrapBBs.resize(CheckHandlerID + 1); 3572 3573 llvm::BasicBlock *&TrapBB = TrapBBs[CheckHandlerID]; 3574 3575 if (!ClSanitizeDebugDeoptimization && 3576 CGM.getCodeGenOpts().OptimizationLevel && TrapBB && 3577 (!CurCodeDecl || !CurCodeDecl->hasAttr<OptimizeNoneAttr>())) { 3578 auto Call = TrapBB->begin(); 3579 assert(isa<llvm::CallInst>(Call) && "Expected call in trap BB"); 3580 3581 Call->applyMergedLocation(Call->getDebugLoc(), 3582 Builder.getCurrentDebugLocation()); 3583 Builder.CreateCondBr(Checked, Cont, TrapBB); 3584 } else { 3585 TrapBB = createBasicBlock("trap"); 3586 Builder.CreateCondBr(Checked, Cont, TrapBB); 3587 EmitBlock(TrapBB); 3588 3589 llvm::CallInst *TrapCall = Builder.CreateCall( 3590 CGM.getIntrinsic(llvm::Intrinsic::ubsantrap), 3591 llvm::ConstantInt::get(CGM.Int8Ty, ClSanitizeDebugDeoptimization 3592 ? TrapBB->getParent()->size() 3593 : CheckHandlerID)); 3594 3595 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) { 3596 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name", 3597 CGM.getCodeGenOpts().TrapFuncName); 3598 TrapCall->addFnAttr(A); 3599 } 3600 TrapCall->setDoesNotReturn(); 3601 TrapCall->setDoesNotThrow(); 3602 Builder.CreateUnreachable(); 3603 } 3604 3605 EmitBlock(Cont); 3606 } 3607 3608 llvm::CallInst *CodeGenFunction::EmitTrapCall(llvm::Intrinsic::ID IntrID) { 3609 llvm::CallInst *TrapCall = 3610 Builder.CreateCall(CGM.getIntrinsic(IntrID)); 3611 3612 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) { 3613 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name", 3614 CGM.getCodeGenOpts().TrapFuncName); 3615 TrapCall->addFnAttr(A); 3616 } 3617 3618 return TrapCall; 3619 } 3620 3621 Address CodeGenFunction::EmitArrayToPointerDecay(const Expr *E, 3622 LValueBaseInfo *BaseInfo, 3623 TBAAAccessInfo *TBAAInfo) { 3624 assert(E->getType()->isArrayType() && 3625 "Array to pointer decay must have array source type!"); 3626 3627 // Expressions of array type can't be bitfields or vector elements. 3628 LValue LV = EmitLValue(E); 3629 Address Addr = LV.getAddress(*this); 3630 3631 // If the array type was an incomplete type, we need to make sure 3632 // the decay ends up being the right type. 3633 llvm::Type *NewTy = ConvertType(E->getType()); 3634 Addr = Addr.withElementType(NewTy); 3635 3636 // Note that VLA pointers are always decayed, so we don't need to do 3637 // anything here. 3638 if (!E->getType()->isVariableArrayType()) { 3639 assert(isa<llvm::ArrayType>(Addr.getElementType()) && 3640 "Expected pointer to array"); 3641 Addr = Builder.CreateConstArrayGEP(Addr, 0, "arraydecay"); 3642 } 3643 3644 // The result of this decay conversion points to an array element within the 3645 // base lvalue. However, since TBAA currently does not support representing 3646 // accesses to elements of member arrays, we conservatively represent accesses 3647 // to the pointee object as if it had no any base lvalue specified. 3648 // TODO: Support TBAA for member arrays. 3649 QualType EltType = E->getType()->castAsArrayTypeUnsafe()->getElementType(); 3650 if (BaseInfo) *BaseInfo = LV.getBaseInfo(); 3651 if (TBAAInfo) *TBAAInfo = CGM.getTBAAAccessInfo(EltType); 3652 3653 return Addr.withElementType(ConvertTypeForMem(EltType)); 3654 } 3655 3656 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an 3657 /// array to pointer, return the array subexpression. 3658 static const Expr *isSimpleArrayDecayOperand(const Expr *E) { 3659 // If this isn't just an array->pointer decay, bail out. 3660 const auto *CE = dyn_cast<CastExpr>(E); 3661 if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay) 3662 return nullptr; 3663 3664 // If this is a decay from variable width array, bail out. 3665 const Expr *SubExpr = CE->getSubExpr(); 3666 if (SubExpr->getType()->isVariableArrayType()) 3667 return nullptr; 3668 3669 return SubExpr; 3670 } 3671 3672 static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF, 3673 llvm::Type *elemType, 3674 llvm::Value *ptr, 3675 ArrayRef<llvm::Value*> indices, 3676 bool inbounds, 3677 bool signedIndices, 3678 SourceLocation loc, 3679 const llvm::Twine &name = "arrayidx") { 3680 if (inbounds) { 3681 return CGF.EmitCheckedInBoundsGEP(elemType, ptr, indices, signedIndices, 3682 CodeGenFunction::NotSubtraction, loc, 3683 name); 3684 } else { 3685 return CGF.Builder.CreateGEP(elemType, ptr, indices, name); 3686 } 3687 } 3688 3689 static CharUnits getArrayElementAlign(CharUnits arrayAlign, 3690 llvm::Value *idx, 3691 CharUnits eltSize) { 3692 // If we have a constant index, we can use the exact offset of the 3693 // element we're accessing. 3694 if (auto constantIdx = dyn_cast<llvm::ConstantInt>(idx)) { 3695 CharUnits offset = constantIdx->getZExtValue() * eltSize; 3696 return arrayAlign.alignmentAtOffset(offset); 3697 3698 // Otherwise, use the worst-case alignment for any element. 3699 } else { 3700 return arrayAlign.alignmentOfArrayElement(eltSize); 3701 } 3702 } 3703 3704 static QualType getFixedSizeElementType(const ASTContext &ctx, 3705 const VariableArrayType *vla) { 3706 QualType eltType; 3707 do { 3708 eltType = vla->getElementType(); 3709 } while ((vla = ctx.getAsVariableArrayType(eltType))); 3710 return eltType; 3711 } 3712 3713 static bool hasBPFPreserveStaticOffset(const RecordDecl *D) { 3714 return D && D->hasAttr<BPFPreserveStaticOffsetAttr>(); 3715 } 3716 3717 static bool hasBPFPreserveStaticOffset(const Expr *E) { 3718 if (!E) 3719 return false; 3720 QualType PointeeType = E->getType()->getPointeeType(); 3721 if (PointeeType.isNull()) 3722 return false; 3723 if (const auto *BaseDecl = PointeeType->getAsRecordDecl()) 3724 return hasBPFPreserveStaticOffset(BaseDecl); 3725 return false; 3726 } 3727 3728 // Wraps Addr with a call to llvm.preserve.static.offset intrinsic. 3729 static Address wrapWithBPFPreserveStaticOffset(CodeGenFunction &CGF, 3730 Address &Addr) { 3731 if (!CGF.getTarget().getTriple().isBPF()) 3732 return Addr; 3733 3734 llvm::Function *Fn = 3735 CGF.CGM.getIntrinsic(llvm::Intrinsic::preserve_static_offset); 3736 llvm::CallInst *Call = CGF.Builder.CreateCall(Fn, {Addr.getPointer()}); 3737 return Address(Call, Addr.getElementType(), Addr.getAlignment()); 3738 } 3739 3740 /// Given an array base, check whether its member access belongs to a record 3741 /// with preserve_access_index attribute or not. 3742 static bool IsPreserveAIArrayBase(CodeGenFunction &CGF, const Expr *ArrayBase) { 3743 if (!ArrayBase || !CGF.getDebugInfo()) 3744 return false; 3745 3746 // Only support base as either a MemberExpr or DeclRefExpr. 3747 // DeclRefExpr to cover cases like: 3748 // struct s { int a; int b[10]; }; 3749 // struct s *p; 3750 // p[1].a 3751 // p[1] will generate a DeclRefExpr and p[1].a is a MemberExpr. 3752 // p->b[5] is a MemberExpr example. 3753 const Expr *E = ArrayBase->IgnoreImpCasts(); 3754 if (const auto *ME = dyn_cast<MemberExpr>(E)) 3755 return ME->getMemberDecl()->hasAttr<BPFPreserveAccessIndexAttr>(); 3756 3757 if (const auto *DRE = dyn_cast<DeclRefExpr>(E)) { 3758 const auto *VarDef = dyn_cast<VarDecl>(DRE->getDecl()); 3759 if (!VarDef) 3760 return false; 3761 3762 const auto *PtrT = VarDef->getType()->getAs<PointerType>(); 3763 if (!PtrT) 3764 return false; 3765 3766 const auto *PointeeT = PtrT->getPointeeType() 3767 ->getUnqualifiedDesugaredType(); 3768 if (const auto *RecT = dyn_cast<RecordType>(PointeeT)) 3769 return RecT->getDecl()->hasAttr<BPFPreserveAccessIndexAttr>(); 3770 return false; 3771 } 3772 3773 return false; 3774 } 3775 3776 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr, 3777 ArrayRef<llvm::Value *> indices, 3778 QualType eltType, bool inbounds, 3779 bool signedIndices, SourceLocation loc, 3780 QualType *arrayType = nullptr, 3781 const Expr *Base = nullptr, 3782 const llvm::Twine &name = "arrayidx") { 3783 // All the indices except that last must be zero. 3784 #ifndef NDEBUG 3785 for (auto *idx : indices.drop_back()) 3786 assert(isa<llvm::ConstantInt>(idx) && 3787 cast<llvm::ConstantInt>(idx)->isZero()); 3788 #endif 3789 3790 // Determine the element size of the statically-sized base. This is 3791 // the thing that the indices are expressed in terms of. 3792 if (auto vla = CGF.getContext().getAsVariableArrayType(eltType)) { 3793 eltType = getFixedSizeElementType(CGF.getContext(), vla); 3794 } 3795 3796 // We can use that to compute the best alignment of the element. 3797 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType); 3798 CharUnits eltAlign = 3799 getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize); 3800 3801 if (hasBPFPreserveStaticOffset(Base)) 3802 addr = wrapWithBPFPreserveStaticOffset(CGF, addr); 3803 3804 llvm::Value *eltPtr; 3805 auto LastIndex = dyn_cast<llvm::ConstantInt>(indices.back()); 3806 if (!LastIndex || 3807 (!CGF.IsInPreservedAIRegion && !IsPreserveAIArrayBase(CGF, Base))) { 3808 eltPtr = emitArraySubscriptGEP( 3809 CGF, addr.getElementType(), addr.getPointer(), indices, inbounds, 3810 signedIndices, loc, name); 3811 } else { 3812 // Remember the original array subscript for bpf target 3813 unsigned idx = LastIndex->getZExtValue(); 3814 llvm::DIType *DbgInfo = nullptr; 3815 if (arrayType) 3816 DbgInfo = CGF.getDebugInfo()->getOrCreateStandaloneType(*arrayType, loc); 3817 eltPtr = CGF.Builder.CreatePreserveArrayAccessIndex(addr.getElementType(), 3818 addr.getPointer(), 3819 indices.size() - 1, 3820 idx, DbgInfo); 3821 } 3822 3823 return Address(eltPtr, CGF.ConvertTypeForMem(eltType), eltAlign); 3824 } 3825 3826 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E, 3827 bool Accessed) { 3828 // The index must always be an integer, which is not an aggregate. Emit it 3829 // in lexical order (this complexity is, sadly, required by C++17). 3830 llvm::Value *IdxPre = 3831 (E->getLHS() == E->getIdx()) ? EmitScalarExpr(E->getIdx()) : nullptr; 3832 bool SignedIndices = false; 3833 auto EmitIdxAfterBase = [&, IdxPre](bool Promote) -> llvm::Value * { 3834 auto *Idx = IdxPre; 3835 if (E->getLHS() != E->getIdx()) { 3836 assert(E->getRHS() == E->getIdx() && "index was neither LHS nor RHS"); 3837 Idx = EmitScalarExpr(E->getIdx()); 3838 } 3839 3840 QualType IdxTy = E->getIdx()->getType(); 3841 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType(); 3842 SignedIndices |= IdxSigned; 3843 3844 if (SanOpts.has(SanitizerKind::ArrayBounds)) 3845 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed); 3846 3847 // Extend or truncate the index type to 32 or 64-bits. 3848 if (Promote && Idx->getType() != IntPtrTy) 3849 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom"); 3850 3851 return Idx; 3852 }; 3853 IdxPre = nullptr; 3854 3855 // If the base is a vector type, then we are forming a vector element lvalue 3856 // with this subscript. 3857 if (E->getBase()->getType()->isVectorType() && 3858 !isa<ExtVectorElementExpr>(E->getBase())) { 3859 // Emit the vector as an lvalue to get its address. 3860 LValue LHS = EmitLValue(E->getBase()); 3861 auto *Idx = EmitIdxAfterBase(/*Promote*/false); 3862 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!"); 3863 return LValue::MakeVectorElt(LHS.getAddress(*this), Idx, 3864 E->getBase()->getType(), LHS.getBaseInfo(), 3865 TBAAAccessInfo()); 3866 } 3867 3868 // All the other cases basically behave like simple offsetting. 3869 3870 // Handle the extvector case we ignored above. 3871 if (isa<ExtVectorElementExpr>(E->getBase())) { 3872 LValue LV = EmitLValue(E->getBase()); 3873 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 3874 Address Addr = EmitExtVectorElementLValue(LV); 3875 3876 QualType EltType = LV.getType()->castAs<VectorType>()->getElementType(); 3877 Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true, 3878 SignedIndices, E->getExprLoc()); 3879 return MakeAddrLValue(Addr, EltType, LV.getBaseInfo(), 3880 CGM.getTBAAInfoForSubobject(LV, EltType)); 3881 } 3882 3883 LValueBaseInfo EltBaseInfo; 3884 TBAAAccessInfo EltTBAAInfo; 3885 Address Addr = Address::invalid(); 3886 if (const VariableArrayType *vla = 3887 getContext().getAsVariableArrayType(E->getType())) { 3888 // The base must be a pointer, which is not an aggregate. Emit 3889 // it. It needs to be emitted first in case it's what captures 3890 // the VLA bounds. 3891 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo); 3892 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 3893 3894 // The element count here is the total number of non-VLA elements. 3895 llvm::Value *numElements = getVLASize(vla).NumElts; 3896 3897 // Effectively, the multiply by the VLA size is part of the GEP. 3898 // GEP indexes are signed, and scaling an index isn't permitted to 3899 // signed-overflow, so we use the same semantics for our explicit 3900 // multiply. We suppress this if overflow is not undefined behavior. 3901 if (getLangOpts().isSignedOverflowDefined()) { 3902 Idx = Builder.CreateMul(Idx, numElements); 3903 } else { 3904 Idx = Builder.CreateNSWMul(Idx, numElements); 3905 } 3906 3907 Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(), 3908 !getLangOpts().isSignedOverflowDefined(), 3909 SignedIndices, E->getExprLoc()); 3910 3911 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){ 3912 // Indexing over an interface, as in "NSString *P; P[4];" 3913 3914 // Emit the base pointer. 3915 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo); 3916 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 3917 3918 CharUnits InterfaceSize = getContext().getTypeSizeInChars(OIT); 3919 llvm::Value *InterfaceSizeVal = 3920 llvm::ConstantInt::get(Idx->getType(), InterfaceSize.getQuantity()); 3921 3922 llvm::Value *ScaledIdx = Builder.CreateMul(Idx, InterfaceSizeVal); 3923 3924 // We don't necessarily build correct LLVM struct types for ObjC 3925 // interfaces, so we can't rely on GEP to do this scaling 3926 // correctly, so we need to cast to i8*. FIXME: is this actually 3927 // true? A lot of other things in the fragile ABI would break... 3928 llvm::Type *OrigBaseElemTy = Addr.getElementType(); 3929 3930 // Do the GEP. 3931 CharUnits EltAlign = 3932 getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize); 3933 llvm::Value *EltPtr = 3934 emitArraySubscriptGEP(*this, Int8Ty, Addr.getPointer(), ScaledIdx, 3935 false, SignedIndices, E->getExprLoc()); 3936 Addr = Address(EltPtr, OrigBaseElemTy, EltAlign); 3937 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) { 3938 // If this is A[i] where A is an array, the frontend will have decayed the 3939 // base to be a ArrayToPointerDecay implicit cast. While correct, it is 3940 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a 3941 // "gep x, i" here. Emit one "gep A, 0, i". 3942 assert(Array->getType()->isArrayType() && 3943 "Array to pointer decay must have array source type!"); 3944 LValue ArrayLV; 3945 // For simple multidimensional array indexing, set the 'accessed' flag for 3946 // better bounds-checking of the base expression. 3947 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array)) 3948 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true); 3949 else 3950 ArrayLV = EmitLValue(Array); 3951 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 3952 3953 // Propagate the alignment from the array itself to the result. 3954 QualType arrayType = Array->getType(); 3955 Addr = emitArraySubscriptGEP( 3956 *this, ArrayLV.getAddress(*this), {CGM.getSize(CharUnits::Zero()), Idx}, 3957 E->getType(), !getLangOpts().isSignedOverflowDefined(), SignedIndices, 3958 E->getExprLoc(), &arrayType, E->getBase()); 3959 EltBaseInfo = ArrayLV.getBaseInfo(); 3960 EltTBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, E->getType()); 3961 } else { 3962 // The base must be a pointer; emit it with an estimate of its alignment. 3963 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo); 3964 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 3965 QualType ptrType = E->getBase()->getType(); 3966 Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(), 3967 !getLangOpts().isSignedOverflowDefined(), 3968 SignedIndices, E->getExprLoc(), &ptrType, 3969 E->getBase()); 3970 } 3971 3972 LValue LV = MakeAddrLValue(Addr, E->getType(), EltBaseInfo, EltTBAAInfo); 3973 3974 if (getLangOpts().ObjC && 3975 getLangOpts().getGC() != LangOptions::NonGC) { 3976 LV.setNonGC(!E->isOBJCGCCandidate(getContext())); 3977 setObjCGCLValueClass(getContext(), E, LV); 3978 } 3979 return LV; 3980 } 3981 3982 LValue CodeGenFunction::EmitMatrixSubscriptExpr(const MatrixSubscriptExpr *E) { 3983 assert( 3984 !E->isIncomplete() && 3985 "incomplete matrix subscript expressions should be rejected during Sema"); 3986 LValue Base = EmitLValue(E->getBase()); 3987 llvm::Value *RowIdx = EmitScalarExpr(E->getRowIdx()); 3988 llvm::Value *ColIdx = EmitScalarExpr(E->getColumnIdx()); 3989 llvm::Value *NumRows = Builder.getIntN( 3990 RowIdx->getType()->getScalarSizeInBits(), 3991 E->getBase()->getType()->castAs<ConstantMatrixType>()->getNumRows()); 3992 llvm::Value *FinalIdx = 3993 Builder.CreateAdd(Builder.CreateMul(ColIdx, NumRows), RowIdx); 3994 return LValue::MakeMatrixElt( 3995 MaybeConvertMatrixAddress(Base.getAddress(*this), *this), FinalIdx, 3996 E->getBase()->getType(), Base.getBaseInfo(), TBAAAccessInfo()); 3997 } 3998 3999 static Address emitOMPArraySectionBase(CodeGenFunction &CGF, const Expr *Base, 4000 LValueBaseInfo &BaseInfo, 4001 TBAAAccessInfo &TBAAInfo, 4002 QualType BaseTy, QualType ElTy, 4003 bool IsLowerBound) { 4004 LValue BaseLVal; 4005 if (auto *ASE = dyn_cast<OMPArraySectionExpr>(Base->IgnoreParenImpCasts())) { 4006 BaseLVal = CGF.EmitOMPArraySectionExpr(ASE, IsLowerBound); 4007 if (BaseTy->isArrayType()) { 4008 Address Addr = BaseLVal.getAddress(CGF); 4009 BaseInfo = BaseLVal.getBaseInfo(); 4010 4011 // If the array type was an incomplete type, we need to make sure 4012 // the decay ends up being the right type. 4013 llvm::Type *NewTy = CGF.ConvertType(BaseTy); 4014 Addr = Addr.withElementType(NewTy); 4015 4016 // Note that VLA pointers are always decayed, so we don't need to do 4017 // anything here. 4018 if (!BaseTy->isVariableArrayType()) { 4019 assert(isa<llvm::ArrayType>(Addr.getElementType()) && 4020 "Expected pointer to array"); 4021 Addr = CGF.Builder.CreateConstArrayGEP(Addr, 0, "arraydecay"); 4022 } 4023 4024 return Addr.withElementType(CGF.ConvertTypeForMem(ElTy)); 4025 } 4026 LValueBaseInfo TypeBaseInfo; 4027 TBAAAccessInfo TypeTBAAInfo; 4028 CharUnits Align = 4029 CGF.CGM.getNaturalTypeAlignment(ElTy, &TypeBaseInfo, &TypeTBAAInfo); 4030 BaseInfo.mergeForCast(TypeBaseInfo); 4031 TBAAInfo = CGF.CGM.mergeTBAAInfoForCast(TBAAInfo, TypeTBAAInfo); 4032 return Address(CGF.Builder.CreateLoad(BaseLVal.getAddress(CGF)), 4033 CGF.ConvertTypeForMem(ElTy), Align); 4034 } 4035 return CGF.EmitPointerWithAlignment(Base, &BaseInfo, &TBAAInfo); 4036 } 4037 4038 LValue CodeGenFunction::EmitOMPArraySectionExpr(const OMPArraySectionExpr *E, 4039 bool IsLowerBound) { 4040 QualType BaseTy = OMPArraySectionExpr::getBaseOriginalType(E->getBase()); 4041 QualType ResultExprTy; 4042 if (auto *AT = getContext().getAsArrayType(BaseTy)) 4043 ResultExprTy = AT->getElementType(); 4044 else 4045 ResultExprTy = BaseTy->getPointeeType(); 4046 llvm::Value *Idx = nullptr; 4047 if (IsLowerBound || E->getColonLocFirst().isInvalid()) { 4048 // Requesting lower bound or upper bound, but without provided length and 4049 // without ':' symbol for the default length -> length = 1. 4050 // Idx = LowerBound ?: 0; 4051 if (auto *LowerBound = E->getLowerBound()) { 4052 Idx = Builder.CreateIntCast( 4053 EmitScalarExpr(LowerBound), IntPtrTy, 4054 LowerBound->getType()->hasSignedIntegerRepresentation()); 4055 } else 4056 Idx = llvm::ConstantInt::getNullValue(IntPtrTy); 4057 } else { 4058 // Try to emit length or lower bound as constant. If this is possible, 1 4059 // is subtracted from constant length or lower bound. Otherwise, emit LLVM 4060 // IR (LB + Len) - 1. 4061 auto &C = CGM.getContext(); 4062 auto *Length = E->getLength(); 4063 llvm::APSInt ConstLength; 4064 if (Length) { 4065 // Idx = LowerBound + Length - 1; 4066 if (std::optional<llvm::APSInt> CL = Length->getIntegerConstantExpr(C)) { 4067 ConstLength = CL->zextOrTrunc(PointerWidthInBits); 4068 Length = nullptr; 4069 } 4070 auto *LowerBound = E->getLowerBound(); 4071 llvm::APSInt ConstLowerBound(PointerWidthInBits, /*isUnsigned=*/false); 4072 if (LowerBound) { 4073 if (std::optional<llvm::APSInt> LB = 4074 LowerBound->getIntegerConstantExpr(C)) { 4075 ConstLowerBound = LB->zextOrTrunc(PointerWidthInBits); 4076 LowerBound = nullptr; 4077 } 4078 } 4079 if (!Length) 4080 --ConstLength; 4081 else if (!LowerBound) 4082 --ConstLowerBound; 4083 4084 if (Length || LowerBound) { 4085 auto *LowerBoundVal = 4086 LowerBound 4087 ? Builder.CreateIntCast( 4088 EmitScalarExpr(LowerBound), IntPtrTy, 4089 LowerBound->getType()->hasSignedIntegerRepresentation()) 4090 : llvm::ConstantInt::get(IntPtrTy, ConstLowerBound); 4091 auto *LengthVal = 4092 Length 4093 ? Builder.CreateIntCast( 4094 EmitScalarExpr(Length), IntPtrTy, 4095 Length->getType()->hasSignedIntegerRepresentation()) 4096 : llvm::ConstantInt::get(IntPtrTy, ConstLength); 4097 Idx = Builder.CreateAdd(LowerBoundVal, LengthVal, "lb_add_len", 4098 /*HasNUW=*/false, 4099 !getLangOpts().isSignedOverflowDefined()); 4100 if (Length && LowerBound) { 4101 Idx = Builder.CreateSub( 4102 Idx, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "idx_sub_1", 4103 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined()); 4104 } 4105 } else 4106 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength + ConstLowerBound); 4107 } else { 4108 // Idx = ArraySize - 1; 4109 QualType ArrayTy = BaseTy->isPointerType() 4110 ? E->getBase()->IgnoreParenImpCasts()->getType() 4111 : BaseTy; 4112 if (auto *VAT = C.getAsVariableArrayType(ArrayTy)) { 4113 Length = VAT->getSizeExpr(); 4114 if (std::optional<llvm::APSInt> L = Length->getIntegerConstantExpr(C)) { 4115 ConstLength = *L; 4116 Length = nullptr; 4117 } 4118 } else { 4119 auto *CAT = C.getAsConstantArrayType(ArrayTy); 4120 assert(CAT && "unexpected type for array initializer"); 4121 ConstLength = CAT->getSize(); 4122 } 4123 if (Length) { 4124 auto *LengthVal = Builder.CreateIntCast( 4125 EmitScalarExpr(Length), IntPtrTy, 4126 Length->getType()->hasSignedIntegerRepresentation()); 4127 Idx = Builder.CreateSub( 4128 LengthVal, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "len_sub_1", 4129 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined()); 4130 } else { 4131 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits); 4132 --ConstLength; 4133 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength); 4134 } 4135 } 4136 } 4137 assert(Idx); 4138 4139 Address EltPtr = Address::invalid(); 4140 LValueBaseInfo BaseInfo; 4141 TBAAAccessInfo TBAAInfo; 4142 if (auto *VLA = getContext().getAsVariableArrayType(ResultExprTy)) { 4143 // The base must be a pointer, which is not an aggregate. Emit 4144 // it. It needs to be emitted first in case it's what captures 4145 // the VLA bounds. 4146 Address Base = 4147 emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, TBAAInfo, 4148 BaseTy, VLA->getElementType(), IsLowerBound); 4149 // The element count here is the total number of non-VLA elements. 4150 llvm::Value *NumElements = getVLASize(VLA).NumElts; 4151 4152 // Effectively, the multiply by the VLA size is part of the GEP. 4153 // GEP indexes are signed, and scaling an index isn't permitted to 4154 // signed-overflow, so we use the same semantics for our explicit 4155 // multiply. We suppress this if overflow is not undefined behavior. 4156 if (getLangOpts().isSignedOverflowDefined()) 4157 Idx = Builder.CreateMul(Idx, NumElements); 4158 else 4159 Idx = Builder.CreateNSWMul(Idx, NumElements); 4160 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(), 4161 !getLangOpts().isSignedOverflowDefined(), 4162 /*signedIndices=*/false, E->getExprLoc()); 4163 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) { 4164 // If this is A[i] where A is an array, the frontend will have decayed the 4165 // base to be a ArrayToPointerDecay implicit cast. While correct, it is 4166 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a 4167 // "gep x, i" here. Emit one "gep A, 0, i". 4168 assert(Array->getType()->isArrayType() && 4169 "Array to pointer decay must have array source type!"); 4170 LValue ArrayLV; 4171 // For simple multidimensional array indexing, set the 'accessed' flag for 4172 // better bounds-checking of the base expression. 4173 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array)) 4174 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true); 4175 else 4176 ArrayLV = EmitLValue(Array); 4177 4178 // Propagate the alignment from the array itself to the result. 4179 EltPtr = emitArraySubscriptGEP( 4180 *this, ArrayLV.getAddress(*this), {CGM.getSize(CharUnits::Zero()), Idx}, 4181 ResultExprTy, !getLangOpts().isSignedOverflowDefined(), 4182 /*signedIndices=*/false, E->getExprLoc()); 4183 BaseInfo = ArrayLV.getBaseInfo(); 4184 TBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, ResultExprTy); 4185 } else { 4186 Address Base = emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, 4187 TBAAInfo, BaseTy, ResultExprTy, 4188 IsLowerBound); 4189 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy, 4190 !getLangOpts().isSignedOverflowDefined(), 4191 /*signedIndices=*/false, E->getExprLoc()); 4192 } 4193 4194 return MakeAddrLValue(EltPtr, ResultExprTy, BaseInfo, TBAAInfo); 4195 } 4196 4197 LValue CodeGenFunction:: 4198 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) { 4199 // Emit the base vector as an l-value. 4200 LValue Base; 4201 4202 // ExtVectorElementExpr's base can either be a vector or pointer to vector. 4203 if (E->isArrow()) { 4204 // If it is a pointer to a vector, emit the address and form an lvalue with 4205 // it. 4206 LValueBaseInfo BaseInfo; 4207 TBAAAccessInfo TBAAInfo; 4208 Address Ptr = EmitPointerWithAlignment(E->getBase(), &BaseInfo, &TBAAInfo); 4209 const auto *PT = E->getBase()->getType()->castAs<PointerType>(); 4210 Base = MakeAddrLValue(Ptr, PT->getPointeeType(), BaseInfo, TBAAInfo); 4211 Base.getQuals().removeObjCGCAttr(); 4212 } else if (E->getBase()->isGLValue()) { 4213 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x), 4214 // emit the base as an lvalue. 4215 assert(E->getBase()->getType()->isVectorType()); 4216 Base = EmitLValue(E->getBase()); 4217 } else { 4218 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such. 4219 assert(E->getBase()->getType()->isVectorType() && 4220 "Result must be a vector"); 4221 llvm::Value *Vec = EmitScalarExpr(E->getBase()); 4222 4223 // Store the vector to memory (because LValue wants an address). 4224 Address VecMem = CreateMemTemp(E->getBase()->getType()); 4225 Builder.CreateStore(Vec, VecMem); 4226 Base = MakeAddrLValue(VecMem, E->getBase()->getType(), 4227 AlignmentSource::Decl); 4228 } 4229 4230 QualType type = 4231 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers()); 4232 4233 // Encode the element access list into a vector of unsigned indices. 4234 SmallVector<uint32_t, 4> Indices; 4235 E->getEncodedElementAccess(Indices); 4236 4237 if (Base.isSimple()) { 4238 llvm::Constant *CV = 4239 llvm::ConstantDataVector::get(getLLVMContext(), Indices); 4240 return LValue::MakeExtVectorElt(Base.getAddress(*this), CV, type, 4241 Base.getBaseInfo(), TBAAAccessInfo()); 4242 } 4243 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!"); 4244 4245 llvm::Constant *BaseElts = Base.getExtVectorElts(); 4246 SmallVector<llvm::Constant *, 4> CElts; 4247 4248 for (unsigned i = 0, e = Indices.size(); i != e; ++i) 4249 CElts.push_back(BaseElts->getAggregateElement(Indices[i])); 4250 llvm::Constant *CV = llvm::ConstantVector::get(CElts); 4251 return LValue::MakeExtVectorElt(Base.getExtVectorAddress(), CV, type, 4252 Base.getBaseInfo(), TBAAAccessInfo()); 4253 } 4254 4255 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) { 4256 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, E)) { 4257 EmitIgnoredExpr(E->getBase()); 4258 return EmitDeclRefLValue(DRE); 4259 } 4260 4261 Expr *BaseExpr = E->getBase(); 4262 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar. 4263 LValue BaseLV; 4264 if (E->isArrow()) { 4265 LValueBaseInfo BaseInfo; 4266 TBAAAccessInfo TBAAInfo; 4267 Address Addr = EmitPointerWithAlignment(BaseExpr, &BaseInfo, &TBAAInfo); 4268 QualType PtrTy = BaseExpr->getType()->getPointeeType(); 4269 SanitizerSet SkippedChecks; 4270 bool IsBaseCXXThis = IsWrappedCXXThis(BaseExpr); 4271 if (IsBaseCXXThis) 4272 SkippedChecks.set(SanitizerKind::Alignment, true); 4273 if (IsBaseCXXThis || isa<DeclRefExpr>(BaseExpr)) 4274 SkippedChecks.set(SanitizerKind::Null, true); 4275 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr.getPointer(), PtrTy, 4276 /*Alignment=*/CharUnits::Zero(), SkippedChecks); 4277 BaseLV = MakeAddrLValue(Addr, PtrTy, BaseInfo, TBAAInfo); 4278 } else 4279 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess); 4280 4281 NamedDecl *ND = E->getMemberDecl(); 4282 if (auto *Field = dyn_cast<FieldDecl>(ND)) { 4283 LValue LV = EmitLValueForField(BaseLV, Field); 4284 setObjCGCLValueClass(getContext(), E, LV); 4285 if (getLangOpts().OpenMP) { 4286 // If the member was explicitly marked as nontemporal, mark it as 4287 // nontemporal. If the base lvalue is marked as nontemporal, mark access 4288 // to children as nontemporal too. 4289 if ((IsWrappedCXXThis(BaseExpr) && 4290 CGM.getOpenMPRuntime().isNontemporalDecl(Field)) || 4291 BaseLV.isNontemporal()) 4292 LV.setNontemporal(/*Value=*/true); 4293 } 4294 return LV; 4295 } 4296 4297 if (const auto *FD = dyn_cast<FunctionDecl>(ND)) 4298 return EmitFunctionDeclLValue(*this, E, FD); 4299 4300 llvm_unreachable("Unhandled member declaration!"); 4301 } 4302 4303 /// Given that we are currently emitting a lambda, emit an l-value for 4304 /// one of its members. 4305 /// 4306 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field, 4307 llvm::Value *ThisValue) { 4308 bool HasExplicitObjectParameter = false; 4309 if (const auto *MD = dyn_cast_if_present<CXXMethodDecl>(CurCodeDecl)) { 4310 HasExplicitObjectParameter = MD->isExplicitObjectMemberFunction(); 4311 assert(MD->getParent()->isLambda()); 4312 assert(MD->getParent() == Field->getParent()); 4313 } 4314 LValue LambdaLV; 4315 if (HasExplicitObjectParameter) { 4316 const VarDecl *D = cast<CXXMethodDecl>(CurCodeDecl)->getParamDecl(0); 4317 auto It = LocalDeclMap.find(D); 4318 assert(It != LocalDeclMap.end() && "explicit parameter not loaded?"); 4319 Address AddrOfExplicitObject = It->getSecond(); 4320 if (D->getType()->isReferenceType()) 4321 LambdaLV = EmitLoadOfReferenceLValue(AddrOfExplicitObject, D->getType(), 4322 AlignmentSource::Decl); 4323 else 4324 LambdaLV = MakeNaturalAlignAddrLValue(AddrOfExplicitObject.getPointer(), 4325 D->getType().getNonReferenceType()); 4326 } else { 4327 QualType LambdaTagType = getContext().getTagDeclType(Field->getParent()); 4328 LambdaLV = MakeNaturalAlignAddrLValue(ThisValue, LambdaTagType); 4329 } 4330 return EmitLValueForField(LambdaLV, Field); 4331 } 4332 4333 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) { 4334 return EmitLValueForLambdaField(Field, CXXABIThisValue); 4335 } 4336 4337 /// Get the field index in the debug info. The debug info structure/union 4338 /// will ignore the unnamed bitfields. 4339 unsigned CodeGenFunction::getDebugInfoFIndex(const RecordDecl *Rec, 4340 unsigned FieldIndex) { 4341 unsigned I = 0, Skipped = 0; 4342 4343 for (auto *F : Rec->getDefinition()->fields()) { 4344 if (I == FieldIndex) 4345 break; 4346 if (F->isUnnamedBitfield()) 4347 Skipped++; 4348 I++; 4349 } 4350 4351 return FieldIndex - Skipped; 4352 } 4353 4354 /// Get the address of a zero-sized field within a record. The resulting 4355 /// address doesn't necessarily have the right type. 4356 static Address emitAddrOfZeroSizeField(CodeGenFunction &CGF, Address Base, 4357 const FieldDecl *Field) { 4358 CharUnits Offset = CGF.getContext().toCharUnitsFromBits( 4359 CGF.getContext().getFieldOffset(Field)); 4360 if (Offset.isZero()) 4361 return Base; 4362 Base = Base.withElementType(CGF.Int8Ty); 4363 return CGF.Builder.CreateConstInBoundsByteGEP(Base, Offset); 4364 } 4365 4366 /// Drill down to the storage of a field without walking into 4367 /// reference types. 4368 /// 4369 /// The resulting address doesn't necessarily have the right type. 4370 static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base, 4371 const FieldDecl *field) { 4372 if (field->isZeroSize(CGF.getContext())) 4373 return emitAddrOfZeroSizeField(CGF, base, field); 4374 4375 const RecordDecl *rec = field->getParent(); 4376 4377 unsigned idx = 4378 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field); 4379 4380 return CGF.Builder.CreateStructGEP(base, idx, field->getName()); 4381 } 4382 4383 static Address emitPreserveStructAccess(CodeGenFunction &CGF, LValue base, 4384 Address addr, const FieldDecl *field) { 4385 const RecordDecl *rec = field->getParent(); 4386 llvm::DIType *DbgInfo = CGF.getDebugInfo()->getOrCreateStandaloneType( 4387 base.getType(), rec->getLocation()); 4388 4389 unsigned idx = 4390 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field); 4391 4392 return CGF.Builder.CreatePreserveStructAccessIndex( 4393 addr, idx, CGF.getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo); 4394 } 4395 4396 static bool hasAnyVptr(const QualType Type, const ASTContext &Context) { 4397 const auto *RD = Type.getTypePtr()->getAsCXXRecordDecl(); 4398 if (!RD) 4399 return false; 4400 4401 if (RD->isDynamicClass()) 4402 return true; 4403 4404 for (const auto &Base : RD->bases()) 4405 if (hasAnyVptr(Base.getType(), Context)) 4406 return true; 4407 4408 for (const FieldDecl *Field : RD->fields()) 4409 if (hasAnyVptr(Field->getType(), Context)) 4410 return true; 4411 4412 return false; 4413 } 4414 4415 LValue CodeGenFunction::EmitLValueForField(LValue base, 4416 const FieldDecl *field) { 4417 LValueBaseInfo BaseInfo = base.getBaseInfo(); 4418 4419 if (field->isBitField()) { 4420 const CGRecordLayout &RL = 4421 CGM.getTypes().getCGRecordLayout(field->getParent()); 4422 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field); 4423 const bool UseVolatile = isAAPCS(CGM.getTarget()) && 4424 CGM.getCodeGenOpts().AAPCSBitfieldWidth && 4425 Info.VolatileStorageSize != 0 && 4426 field->getType() 4427 .withCVRQualifiers(base.getVRQualifiers()) 4428 .isVolatileQualified(); 4429 Address Addr = base.getAddress(*this); 4430 unsigned Idx = RL.getLLVMFieldNo(field); 4431 const RecordDecl *rec = field->getParent(); 4432 if (hasBPFPreserveStaticOffset(rec)) 4433 Addr = wrapWithBPFPreserveStaticOffset(*this, Addr); 4434 if (!UseVolatile) { 4435 if (!IsInPreservedAIRegion && 4436 (!getDebugInfo() || !rec->hasAttr<BPFPreserveAccessIndexAttr>())) { 4437 if (Idx != 0) 4438 // For structs, we GEP to the field that the record layout suggests. 4439 Addr = Builder.CreateStructGEP(Addr, Idx, field->getName()); 4440 } else { 4441 llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateRecordType( 4442 getContext().getRecordType(rec), rec->getLocation()); 4443 Addr = Builder.CreatePreserveStructAccessIndex( 4444 Addr, Idx, getDebugInfoFIndex(rec, field->getFieldIndex()), 4445 DbgInfo); 4446 } 4447 } 4448 const unsigned SS = 4449 UseVolatile ? Info.VolatileStorageSize : Info.StorageSize; 4450 // Get the access type. 4451 llvm::Type *FieldIntTy = llvm::Type::getIntNTy(getLLVMContext(), SS); 4452 Addr = Addr.withElementType(FieldIntTy); 4453 if (UseVolatile) { 4454 const unsigned VolatileOffset = Info.VolatileStorageOffset.getQuantity(); 4455 if (VolatileOffset) 4456 Addr = Builder.CreateConstInBoundsGEP(Addr, VolatileOffset); 4457 } 4458 4459 QualType fieldType = 4460 field->getType().withCVRQualifiers(base.getVRQualifiers()); 4461 // TODO: Support TBAA for bit fields. 4462 LValueBaseInfo FieldBaseInfo(BaseInfo.getAlignmentSource()); 4463 return LValue::MakeBitfield(Addr, Info, fieldType, FieldBaseInfo, 4464 TBAAAccessInfo()); 4465 } 4466 4467 // Fields of may-alias structures are may-alias themselves. 4468 // FIXME: this should get propagated down through anonymous structs 4469 // and unions. 4470 QualType FieldType = field->getType(); 4471 const RecordDecl *rec = field->getParent(); 4472 AlignmentSource BaseAlignSource = BaseInfo.getAlignmentSource(); 4473 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(BaseAlignSource)); 4474 TBAAAccessInfo FieldTBAAInfo; 4475 if (base.getTBAAInfo().isMayAlias() || 4476 rec->hasAttr<MayAliasAttr>() || FieldType->isVectorType()) { 4477 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo(); 4478 } else if (rec->isUnion()) { 4479 // TODO: Support TBAA for unions. 4480 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo(); 4481 } else { 4482 // If no base type been assigned for the base access, then try to generate 4483 // one for this base lvalue. 4484 FieldTBAAInfo = base.getTBAAInfo(); 4485 if (!FieldTBAAInfo.BaseType) { 4486 FieldTBAAInfo.BaseType = CGM.getTBAABaseTypeInfo(base.getType()); 4487 assert(!FieldTBAAInfo.Offset && 4488 "Nonzero offset for an access with no base type!"); 4489 } 4490 4491 // Adjust offset to be relative to the base type. 4492 const ASTRecordLayout &Layout = 4493 getContext().getASTRecordLayout(field->getParent()); 4494 unsigned CharWidth = getContext().getCharWidth(); 4495 if (FieldTBAAInfo.BaseType) 4496 FieldTBAAInfo.Offset += 4497 Layout.getFieldOffset(field->getFieldIndex()) / CharWidth; 4498 4499 // Update the final access type and size. 4500 FieldTBAAInfo.AccessType = CGM.getTBAATypeInfo(FieldType); 4501 FieldTBAAInfo.Size = 4502 getContext().getTypeSizeInChars(FieldType).getQuantity(); 4503 } 4504 4505 Address addr = base.getAddress(*this); 4506 if (hasBPFPreserveStaticOffset(rec)) 4507 addr = wrapWithBPFPreserveStaticOffset(*this, addr); 4508 if (auto *ClassDef = dyn_cast<CXXRecordDecl>(rec)) { 4509 if (CGM.getCodeGenOpts().StrictVTablePointers && 4510 ClassDef->isDynamicClass()) { 4511 // Getting to any field of dynamic object requires stripping dynamic 4512 // information provided by invariant.group. This is because accessing 4513 // fields may leak the real address of dynamic object, which could result 4514 // in miscompilation when leaked pointer would be compared. 4515 auto *stripped = Builder.CreateStripInvariantGroup(addr.getPointer()); 4516 addr = Address(stripped, addr.getElementType(), addr.getAlignment()); 4517 } 4518 } 4519 4520 unsigned RecordCVR = base.getVRQualifiers(); 4521 if (rec->isUnion()) { 4522 // For unions, there is no pointer adjustment. 4523 if (CGM.getCodeGenOpts().StrictVTablePointers && 4524 hasAnyVptr(FieldType, getContext())) 4525 // Because unions can easily skip invariant.barriers, we need to add 4526 // a barrier every time CXXRecord field with vptr is referenced. 4527 addr = Builder.CreateLaunderInvariantGroup(addr); 4528 4529 if (IsInPreservedAIRegion || 4530 (getDebugInfo() && rec->hasAttr<BPFPreserveAccessIndexAttr>())) { 4531 // Remember the original union field index 4532 llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateStandaloneType(base.getType(), 4533 rec->getLocation()); 4534 addr = Address( 4535 Builder.CreatePreserveUnionAccessIndex( 4536 addr.getPointer(), getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo), 4537 addr.getElementType(), addr.getAlignment()); 4538 } 4539 4540 if (FieldType->isReferenceType()) 4541 addr = addr.withElementType(CGM.getTypes().ConvertTypeForMem(FieldType)); 4542 } else { 4543 if (!IsInPreservedAIRegion && 4544 (!getDebugInfo() || !rec->hasAttr<BPFPreserveAccessIndexAttr>())) 4545 // For structs, we GEP to the field that the record layout suggests. 4546 addr = emitAddrOfFieldStorage(*this, addr, field); 4547 else 4548 // Remember the original struct field index 4549 addr = emitPreserveStructAccess(*this, base, addr, field); 4550 } 4551 4552 // If this is a reference field, load the reference right now. 4553 if (FieldType->isReferenceType()) { 4554 LValue RefLVal = 4555 MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo); 4556 if (RecordCVR & Qualifiers::Volatile) 4557 RefLVal.getQuals().addVolatile(); 4558 addr = EmitLoadOfReference(RefLVal, &FieldBaseInfo, &FieldTBAAInfo); 4559 4560 // Qualifiers on the struct don't apply to the referencee. 4561 RecordCVR = 0; 4562 FieldType = FieldType->getPointeeType(); 4563 } 4564 4565 // Make sure that the address is pointing to the right type. This is critical 4566 // for both unions and structs. 4567 addr = addr.withElementType(CGM.getTypes().ConvertTypeForMem(FieldType)); 4568 4569 if (field->hasAttr<AnnotateAttr>()) 4570 addr = EmitFieldAnnotations(field, addr); 4571 4572 LValue LV = MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo); 4573 LV.getQuals().addCVRQualifiers(RecordCVR); 4574 4575 // __weak attribute on a field is ignored. 4576 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak) 4577 LV.getQuals().removeObjCGCAttr(); 4578 4579 return LV; 4580 } 4581 4582 LValue 4583 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base, 4584 const FieldDecl *Field) { 4585 QualType FieldType = Field->getType(); 4586 4587 if (!FieldType->isReferenceType()) 4588 return EmitLValueForField(Base, Field); 4589 4590 Address V = emitAddrOfFieldStorage(*this, Base.getAddress(*this), Field); 4591 4592 // Make sure that the address is pointing to the right type. 4593 llvm::Type *llvmType = ConvertTypeForMem(FieldType); 4594 V = V.withElementType(llvmType); 4595 4596 // TODO: Generate TBAA information that describes this access as a structure 4597 // member access and not just an access to an object of the field's type. This 4598 // should be similar to what we do in EmitLValueForField(). 4599 LValueBaseInfo BaseInfo = Base.getBaseInfo(); 4600 AlignmentSource FieldAlignSource = BaseInfo.getAlignmentSource(); 4601 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(FieldAlignSource)); 4602 return MakeAddrLValue(V, FieldType, FieldBaseInfo, 4603 CGM.getTBAAInfoForSubobject(Base, FieldType)); 4604 } 4605 4606 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){ 4607 if (E->isFileScope()) { 4608 ConstantAddress GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E); 4609 return MakeAddrLValue(GlobalPtr, E->getType(), AlignmentSource::Decl); 4610 } 4611 if (E->getType()->isVariablyModifiedType()) 4612 // make sure to emit the VLA size. 4613 EmitVariablyModifiedType(E->getType()); 4614 4615 Address DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral"); 4616 const Expr *InitExpr = E->getInitializer(); 4617 LValue Result = MakeAddrLValue(DeclPtr, E->getType(), AlignmentSource::Decl); 4618 4619 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(), 4620 /*Init*/ true); 4621 4622 // Block-scope compound literals are destroyed at the end of the enclosing 4623 // scope in C. 4624 if (!getLangOpts().CPlusPlus) 4625 if (QualType::DestructionKind DtorKind = E->getType().isDestructedType()) 4626 pushLifetimeExtendedDestroy(getCleanupKind(DtorKind), DeclPtr, 4627 E->getType(), getDestroyer(DtorKind), 4628 DtorKind & EHCleanup); 4629 4630 return Result; 4631 } 4632 4633 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) { 4634 if (!E->isGLValue()) 4635 // Initializing an aggregate temporary in C++11: T{...}. 4636 return EmitAggExprToLValue(E); 4637 4638 // An lvalue initializer list must be initializing a reference. 4639 assert(E->isTransparent() && "non-transparent glvalue init list"); 4640 return EmitLValue(E->getInit(0)); 4641 } 4642 4643 /// Emit the operand of a glvalue conditional operator. This is either a glvalue 4644 /// or a (possibly-parenthesized) throw-expression. If this is a throw, no 4645 /// LValue is returned and the current block has been terminated. 4646 static std::optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF, 4647 const Expr *Operand) { 4648 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) { 4649 CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false); 4650 return std::nullopt; 4651 } 4652 4653 return CGF.EmitLValue(Operand); 4654 } 4655 4656 namespace { 4657 // Handle the case where the condition is a constant evaluatable simple integer, 4658 // which means we don't have to separately handle the true/false blocks. 4659 std::optional<LValue> HandleConditionalOperatorLValueSimpleCase( 4660 CodeGenFunction &CGF, const AbstractConditionalOperator *E) { 4661 const Expr *condExpr = E->getCond(); 4662 bool CondExprBool; 4663 if (CGF.ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) { 4664 const Expr *Live = E->getTrueExpr(), *Dead = E->getFalseExpr(); 4665 if (!CondExprBool) 4666 std::swap(Live, Dead); 4667 4668 if (!CGF.ContainsLabel(Dead)) { 4669 // If the true case is live, we need to track its region. 4670 if (CondExprBool) 4671 CGF.incrementProfileCounter(E); 4672 // If a throw expression we emit it and return an undefined lvalue 4673 // because it can't be used. 4674 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Live->IgnoreParens())) { 4675 CGF.EmitCXXThrowExpr(ThrowExpr); 4676 llvm::Type *ElemTy = CGF.ConvertType(Dead->getType()); 4677 llvm::Type *Ty = CGF.UnqualPtrTy; 4678 return CGF.MakeAddrLValue( 4679 Address(llvm::UndefValue::get(Ty), ElemTy, CharUnits::One()), 4680 Dead->getType()); 4681 } 4682 return CGF.EmitLValue(Live); 4683 } 4684 } 4685 return std::nullopt; 4686 } 4687 struct ConditionalInfo { 4688 llvm::BasicBlock *lhsBlock, *rhsBlock; 4689 std::optional<LValue> LHS, RHS; 4690 }; 4691 4692 // Create and generate the 3 blocks for a conditional operator. 4693 // Leaves the 'current block' in the continuation basic block. 4694 template<typename FuncTy> 4695 ConditionalInfo EmitConditionalBlocks(CodeGenFunction &CGF, 4696 const AbstractConditionalOperator *E, 4697 const FuncTy &BranchGenFunc) { 4698 ConditionalInfo Info{CGF.createBasicBlock("cond.true"), 4699 CGF.createBasicBlock("cond.false"), std::nullopt, 4700 std::nullopt}; 4701 llvm::BasicBlock *endBlock = CGF.createBasicBlock("cond.end"); 4702 4703 CodeGenFunction::ConditionalEvaluation eval(CGF); 4704 CGF.EmitBranchOnBoolExpr(E->getCond(), Info.lhsBlock, Info.rhsBlock, 4705 CGF.getProfileCount(E)); 4706 4707 // Any temporaries created here are conditional. 4708 CGF.EmitBlock(Info.lhsBlock); 4709 CGF.incrementProfileCounter(E); 4710 eval.begin(CGF); 4711 Info.LHS = BranchGenFunc(CGF, E->getTrueExpr()); 4712 eval.end(CGF); 4713 Info.lhsBlock = CGF.Builder.GetInsertBlock(); 4714 4715 if (Info.LHS) 4716 CGF.Builder.CreateBr(endBlock); 4717 4718 // Any temporaries created here are conditional. 4719 CGF.EmitBlock(Info.rhsBlock); 4720 eval.begin(CGF); 4721 Info.RHS = BranchGenFunc(CGF, E->getFalseExpr()); 4722 eval.end(CGF); 4723 Info.rhsBlock = CGF.Builder.GetInsertBlock(); 4724 CGF.EmitBlock(endBlock); 4725 4726 return Info; 4727 } 4728 } // namespace 4729 4730 void CodeGenFunction::EmitIgnoredConditionalOperator( 4731 const AbstractConditionalOperator *E) { 4732 if (!E->isGLValue()) { 4733 // ?: here should be an aggregate. 4734 assert(hasAggregateEvaluationKind(E->getType()) && 4735 "Unexpected conditional operator!"); 4736 return (void)EmitAggExprToLValue(E); 4737 } 4738 4739 OpaqueValueMapping binding(*this, E); 4740 if (HandleConditionalOperatorLValueSimpleCase(*this, E)) 4741 return; 4742 4743 EmitConditionalBlocks(*this, E, [](CodeGenFunction &CGF, const Expr *E) { 4744 CGF.EmitIgnoredExpr(E); 4745 return LValue{}; 4746 }); 4747 } 4748 LValue CodeGenFunction::EmitConditionalOperatorLValue( 4749 const AbstractConditionalOperator *expr) { 4750 if (!expr->isGLValue()) { 4751 // ?: here should be an aggregate. 4752 assert(hasAggregateEvaluationKind(expr->getType()) && 4753 "Unexpected conditional operator!"); 4754 return EmitAggExprToLValue(expr); 4755 } 4756 4757 OpaqueValueMapping binding(*this, expr); 4758 if (std::optional<LValue> Res = 4759 HandleConditionalOperatorLValueSimpleCase(*this, expr)) 4760 return *Res; 4761 4762 ConditionalInfo Info = EmitConditionalBlocks( 4763 *this, expr, [](CodeGenFunction &CGF, const Expr *E) { 4764 return EmitLValueOrThrowExpression(CGF, E); 4765 }); 4766 4767 if ((Info.LHS && !Info.LHS->isSimple()) || 4768 (Info.RHS && !Info.RHS->isSimple())) 4769 return EmitUnsupportedLValue(expr, "conditional operator"); 4770 4771 if (Info.LHS && Info.RHS) { 4772 Address lhsAddr = Info.LHS->getAddress(*this); 4773 Address rhsAddr = Info.RHS->getAddress(*this); 4774 llvm::PHINode *phi = Builder.CreatePHI(lhsAddr.getType(), 2, "cond-lvalue"); 4775 phi->addIncoming(lhsAddr.getPointer(), Info.lhsBlock); 4776 phi->addIncoming(rhsAddr.getPointer(), Info.rhsBlock); 4777 Address result(phi, lhsAddr.getElementType(), 4778 std::min(lhsAddr.getAlignment(), rhsAddr.getAlignment())); 4779 AlignmentSource alignSource = 4780 std::max(Info.LHS->getBaseInfo().getAlignmentSource(), 4781 Info.RHS->getBaseInfo().getAlignmentSource()); 4782 TBAAAccessInfo TBAAInfo = CGM.mergeTBAAInfoForConditionalOperator( 4783 Info.LHS->getTBAAInfo(), Info.RHS->getTBAAInfo()); 4784 return MakeAddrLValue(result, expr->getType(), LValueBaseInfo(alignSource), 4785 TBAAInfo); 4786 } else { 4787 assert((Info.LHS || Info.RHS) && 4788 "both operands of glvalue conditional are throw-expressions?"); 4789 return Info.LHS ? *Info.LHS : *Info.RHS; 4790 } 4791 } 4792 4793 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference 4794 /// type. If the cast is to a reference, we can have the usual lvalue result, 4795 /// otherwise if a cast is needed by the code generator in an lvalue context, 4796 /// then it must mean that we need the address of an aggregate in order to 4797 /// access one of its members. This can happen for all the reasons that casts 4798 /// are permitted with aggregate result, including noop aggregate casts, and 4799 /// cast from scalar to union. 4800 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) { 4801 switch (E->getCastKind()) { 4802 case CK_ToVoid: 4803 case CK_BitCast: 4804 case CK_LValueToRValueBitCast: 4805 case CK_ArrayToPointerDecay: 4806 case CK_FunctionToPointerDecay: 4807 case CK_NullToMemberPointer: 4808 case CK_NullToPointer: 4809 case CK_IntegralToPointer: 4810 case CK_PointerToIntegral: 4811 case CK_PointerToBoolean: 4812 case CK_IntegralCast: 4813 case CK_BooleanToSignedIntegral: 4814 case CK_IntegralToBoolean: 4815 case CK_IntegralToFloating: 4816 case CK_FloatingToIntegral: 4817 case CK_FloatingToBoolean: 4818 case CK_FloatingCast: 4819 case CK_FloatingRealToComplex: 4820 case CK_FloatingComplexToReal: 4821 case CK_FloatingComplexToBoolean: 4822 case CK_FloatingComplexCast: 4823 case CK_FloatingComplexToIntegralComplex: 4824 case CK_IntegralRealToComplex: 4825 case CK_IntegralComplexToReal: 4826 case CK_IntegralComplexToBoolean: 4827 case CK_IntegralComplexCast: 4828 case CK_IntegralComplexToFloatingComplex: 4829 case CK_DerivedToBaseMemberPointer: 4830 case CK_BaseToDerivedMemberPointer: 4831 case CK_MemberPointerToBoolean: 4832 case CK_ReinterpretMemberPointer: 4833 case CK_AnyPointerToBlockPointerCast: 4834 case CK_ARCProduceObject: 4835 case CK_ARCConsumeObject: 4836 case CK_ARCReclaimReturnedObject: 4837 case CK_ARCExtendBlockObject: 4838 case CK_CopyAndAutoreleaseBlockObject: 4839 case CK_IntToOCLSampler: 4840 case CK_FloatingToFixedPoint: 4841 case CK_FixedPointToFloating: 4842 case CK_FixedPointCast: 4843 case CK_FixedPointToBoolean: 4844 case CK_FixedPointToIntegral: 4845 case CK_IntegralToFixedPoint: 4846 case CK_MatrixCast: 4847 return EmitUnsupportedLValue(E, "unexpected cast lvalue"); 4848 4849 case CK_Dependent: 4850 llvm_unreachable("dependent cast kind in IR gen!"); 4851 4852 case CK_BuiltinFnToFnPtr: 4853 llvm_unreachable("builtin functions are handled elsewhere"); 4854 4855 // These are never l-values; just use the aggregate emission code. 4856 case CK_NonAtomicToAtomic: 4857 case CK_AtomicToNonAtomic: 4858 return EmitAggExprToLValue(E); 4859 4860 case CK_Dynamic: { 4861 LValue LV = EmitLValue(E->getSubExpr()); 4862 Address V = LV.getAddress(*this); 4863 const auto *DCE = cast<CXXDynamicCastExpr>(E); 4864 return MakeNaturalAlignAddrLValue(EmitDynamicCast(V, DCE), E->getType()); 4865 } 4866 4867 case CK_ConstructorConversion: 4868 case CK_UserDefinedConversion: 4869 case CK_CPointerToObjCPointerCast: 4870 case CK_BlockPointerToObjCPointerCast: 4871 case CK_LValueToRValue: 4872 return EmitLValue(E->getSubExpr()); 4873 4874 case CK_NoOp: { 4875 // CK_NoOp can model a qualification conversion, which can remove an array 4876 // bound and change the IR type. 4877 // FIXME: Once pointee types are removed from IR, remove this. 4878 LValue LV = EmitLValue(E->getSubExpr()); 4879 // Propagate the volatile qualifer to LValue, if exist in E. 4880 if (E->changesVolatileQualification()) 4881 LV.getQuals() = E->getType().getQualifiers(); 4882 if (LV.isSimple()) { 4883 Address V = LV.getAddress(*this); 4884 if (V.isValid()) { 4885 llvm::Type *T = ConvertTypeForMem(E->getType()); 4886 if (V.getElementType() != T) 4887 LV.setAddress(V.withElementType(T)); 4888 } 4889 } 4890 return LV; 4891 } 4892 4893 case CK_UncheckedDerivedToBase: 4894 case CK_DerivedToBase: { 4895 const auto *DerivedClassTy = 4896 E->getSubExpr()->getType()->castAs<RecordType>(); 4897 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 4898 4899 LValue LV = EmitLValue(E->getSubExpr()); 4900 Address This = LV.getAddress(*this); 4901 4902 // Perform the derived-to-base conversion 4903 Address Base = GetAddressOfBaseClass( 4904 This, DerivedClassDecl, E->path_begin(), E->path_end(), 4905 /*NullCheckValue=*/false, E->getExprLoc()); 4906 4907 // TODO: Support accesses to members of base classes in TBAA. For now, we 4908 // conservatively pretend that the complete object is of the base class 4909 // type. 4910 return MakeAddrLValue(Base, E->getType(), LV.getBaseInfo(), 4911 CGM.getTBAAInfoForSubobject(LV, E->getType())); 4912 } 4913 case CK_ToUnion: 4914 return EmitAggExprToLValue(E); 4915 case CK_BaseToDerived: { 4916 const auto *DerivedClassTy = E->getType()->castAs<RecordType>(); 4917 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 4918 4919 LValue LV = EmitLValue(E->getSubExpr()); 4920 4921 // Perform the base-to-derived conversion 4922 Address Derived = GetAddressOfDerivedClass( 4923 LV.getAddress(*this), DerivedClassDecl, E->path_begin(), E->path_end(), 4924 /*NullCheckValue=*/false); 4925 4926 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is 4927 // performed and the object is not of the derived type. 4928 if (sanitizePerformTypeCheck()) 4929 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(), 4930 Derived.getPointer(), E->getType()); 4931 4932 if (SanOpts.has(SanitizerKind::CFIDerivedCast)) 4933 EmitVTablePtrCheckForCast(E->getType(), Derived, 4934 /*MayBeNull=*/false, CFITCK_DerivedCast, 4935 E->getBeginLoc()); 4936 4937 return MakeAddrLValue(Derived, E->getType(), LV.getBaseInfo(), 4938 CGM.getTBAAInfoForSubobject(LV, E->getType())); 4939 } 4940 case CK_LValueBitCast: { 4941 // This must be a reinterpret_cast (or c-style equivalent). 4942 const auto *CE = cast<ExplicitCastExpr>(E); 4943 4944 CGM.EmitExplicitCastExprType(CE, this); 4945 LValue LV = EmitLValue(E->getSubExpr()); 4946 Address V = LV.getAddress(*this).withElementType( 4947 ConvertTypeForMem(CE->getTypeAsWritten()->getPointeeType())); 4948 4949 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast)) 4950 EmitVTablePtrCheckForCast(E->getType(), V, 4951 /*MayBeNull=*/false, CFITCK_UnrelatedCast, 4952 E->getBeginLoc()); 4953 4954 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(), 4955 CGM.getTBAAInfoForSubobject(LV, E->getType())); 4956 } 4957 case CK_AddressSpaceConversion: { 4958 LValue LV = EmitLValue(E->getSubExpr()); 4959 QualType DestTy = getContext().getPointerType(E->getType()); 4960 llvm::Value *V = getTargetHooks().performAddrSpaceCast( 4961 *this, LV.getPointer(*this), 4962 E->getSubExpr()->getType().getAddressSpace(), 4963 E->getType().getAddressSpace(), ConvertType(DestTy)); 4964 return MakeAddrLValue(Address(V, ConvertTypeForMem(E->getType()), 4965 LV.getAddress(*this).getAlignment()), 4966 E->getType(), LV.getBaseInfo(), LV.getTBAAInfo()); 4967 } 4968 case CK_ObjCObjectLValueCast: { 4969 LValue LV = EmitLValue(E->getSubExpr()); 4970 Address V = LV.getAddress(*this).withElementType(ConvertType(E->getType())); 4971 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(), 4972 CGM.getTBAAInfoForSubobject(LV, E->getType())); 4973 } 4974 case CK_ZeroToOCLOpaqueType: 4975 llvm_unreachable("NULL to OpenCL opaque type lvalue cast is not valid"); 4976 4977 case CK_VectorSplat: { 4978 // LValue results of vector splats are only supported in HLSL. 4979 if (!getLangOpts().HLSL) 4980 return EmitUnsupportedLValue(E, "unexpected cast lvalue"); 4981 return EmitLValue(E->getSubExpr()); 4982 } 4983 } 4984 4985 llvm_unreachable("Unhandled lvalue cast kind?"); 4986 } 4987 4988 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) { 4989 assert(OpaqueValueMappingData::shouldBindAsLValue(e)); 4990 return getOrCreateOpaqueLValueMapping(e); 4991 } 4992 4993 LValue 4994 CodeGenFunction::getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e) { 4995 assert(OpaqueValueMapping::shouldBindAsLValue(e)); 4996 4997 llvm::DenseMap<const OpaqueValueExpr*,LValue>::iterator 4998 it = OpaqueLValues.find(e); 4999 5000 if (it != OpaqueLValues.end()) 5001 return it->second; 5002 5003 assert(e->isUnique() && "LValue for a nonunique OVE hasn't been emitted"); 5004 return EmitLValue(e->getSourceExpr()); 5005 } 5006 5007 RValue 5008 CodeGenFunction::getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e) { 5009 assert(!OpaqueValueMapping::shouldBindAsLValue(e)); 5010 5011 llvm::DenseMap<const OpaqueValueExpr*,RValue>::iterator 5012 it = OpaqueRValues.find(e); 5013 5014 if (it != OpaqueRValues.end()) 5015 return it->second; 5016 5017 assert(e->isUnique() && "RValue for a nonunique OVE hasn't been emitted"); 5018 return EmitAnyExpr(e->getSourceExpr()); 5019 } 5020 5021 RValue CodeGenFunction::EmitRValueForField(LValue LV, 5022 const FieldDecl *FD, 5023 SourceLocation Loc) { 5024 QualType FT = FD->getType(); 5025 LValue FieldLV = EmitLValueForField(LV, FD); 5026 switch (getEvaluationKind(FT)) { 5027 case TEK_Complex: 5028 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc)); 5029 case TEK_Aggregate: 5030 return FieldLV.asAggregateRValue(*this); 5031 case TEK_Scalar: 5032 // This routine is used to load fields one-by-one to perform a copy, so 5033 // don't load reference fields. 5034 if (FD->getType()->isReferenceType()) 5035 return RValue::get(FieldLV.getPointer(*this)); 5036 // Call EmitLoadOfScalar except when the lvalue is a bitfield to emit a 5037 // primitive load. 5038 if (FieldLV.isBitField()) 5039 return EmitLoadOfLValue(FieldLV, Loc); 5040 return RValue::get(EmitLoadOfScalar(FieldLV, Loc)); 5041 } 5042 llvm_unreachable("bad evaluation kind"); 5043 } 5044 5045 //===--------------------------------------------------------------------===// 5046 // Expression Emission 5047 //===--------------------------------------------------------------------===// 5048 5049 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E, 5050 ReturnValueSlot ReturnValue) { 5051 // Builtins never have block type. 5052 if (E->getCallee()->getType()->isBlockPointerType()) 5053 return EmitBlockCallExpr(E, ReturnValue); 5054 5055 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E)) 5056 return EmitCXXMemberCallExpr(CE, ReturnValue); 5057 5058 if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E)) 5059 return EmitCUDAKernelCallExpr(CE, ReturnValue); 5060 5061 // A CXXOperatorCallExpr is created even for explicit object methods, but 5062 // these should be treated like static function call. 5063 if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E)) 5064 if (const auto *MD = 5065 dyn_cast_if_present<CXXMethodDecl>(CE->getCalleeDecl()); 5066 MD && MD->isImplicitObjectMemberFunction()) 5067 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue); 5068 5069 CGCallee callee = EmitCallee(E->getCallee()); 5070 5071 if (callee.isBuiltin()) { 5072 return EmitBuiltinExpr(callee.getBuiltinDecl(), callee.getBuiltinID(), 5073 E, ReturnValue); 5074 } 5075 5076 if (callee.isPseudoDestructor()) { 5077 return EmitCXXPseudoDestructorExpr(callee.getPseudoDestructorExpr()); 5078 } 5079 5080 return EmitCall(E->getCallee()->getType(), callee, E, ReturnValue); 5081 } 5082 5083 /// Emit a CallExpr without considering whether it might be a subclass. 5084 RValue CodeGenFunction::EmitSimpleCallExpr(const CallExpr *E, 5085 ReturnValueSlot ReturnValue) { 5086 CGCallee Callee = EmitCallee(E->getCallee()); 5087 return EmitCall(E->getCallee()->getType(), Callee, E, ReturnValue); 5088 } 5089 5090 // Detect the unusual situation where an inline version is shadowed by a 5091 // non-inline version. In that case we should pick the external one 5092 // everywhere. That's GCC behavior too. 5093 static bool OnlyHasInlineBuiltinDeclaration(const FunctionDecl *FD) { 5094 for (const FunctionDecl *PD = FD; PD; PD = PD->getPreviousDecl()) 5095 if (!PD->isInlineBuiltinDeclaration()) 5096 return false; 5097 return true; 5098 } 5099 5100 static CGCallee EmitDirectCallee(CodeGenFunction &CGF, GlobalDecl GD) { 5101 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 5102 5103 if (auto builtinID = FD->getBuiltinID()) { 5104 std::string NoBuiltinFD = ("no-builtin-" + FD->getName()).str(); 5105 std::string NoBuiltins = "no-builtins"; 5106 5107 StringRef Ident = CGF.CGM.getMangledName(GD); 5108 std::string FDInlineName = (Ident + ".inline").str(); 5109 5110 bool IsPredefinedLibFunction = 5111 CGF.getContext().BuiltinInfo.isPredefinedLibFunction(builtinID); 5112 bool HasAttributeNoBuiltin = 5113 CGF.CurFn->getAttributes().hasFnAttr(NoBuiltinFD) || 5114 CGF.CurFn->getAttributes().hasFnAttr(NoBuiltins); 5115 5116 // When directing calling an inline builtin, call it through it's mangled 5117 // name to make it clear it's not the actual builtin. 5118 if (CGF.CurFn->getName() != FDInlineName && 5119 OnlyHasInlineBuiltinDeclaration(FD)) { 5120 llvm::Constant *CalleePtr = EmitFunctionDeclPointer(CGF.CGM, GD); 5121 llvm::Function *Fn = llvm::cast<llvm::Function>(CalleePtr); 5122 llvm::Module *M = Fn->getParent(); 5123 llvm::Function *Clone = M->getFunction(FDInlineName); 5124 if (!Clone) { 5125 Clone = llvm::Function::Create(Fn->getFunctionType(), 5126 llvm::GlobalValue::InternalLinkage, 5127 Fn->getAddressSpace(), FDInlineName, M); 5128 Clone->addFnAttr(llvm::Attribute::AlwaysInline); 5129 } 5130 return CGCallee::forDirect(Clone, GD); 5131 } 5132 5133 // Replaceable builtins provide their own implementation of a builtin. If we 5134 // are in an inline builtin implementation, avoid trivial infinite 5135 // recursion. Honor __attribute__((no_builtin("foo"))) or 5136 // __attribute__((no_builtin)) on the current function unless foo is 5137 // not a predefined library function which means we must generate the 5138 // builtin no matter what. 5139 else if (!IsPredefinedLibFunction || !HasAttributeNoBuiltin) 5140 return CGCallee::forBuiltin(builtinID, FD); 5141 } 5142 5143 llvm::Constant *CalleePtr = EmitFunctionDeclPointer(CGF.CGM, GD); 5144 if (CGF.CGM.getLangOpts().CUDA && !CGF.CGM.getLangOpts().CUDAIsDevice && 5145 FD->hasAttr<CUDAGlobalAttr>()) 5146 CalleePtr = CGF.CGM.getCUDARuntime().getKernelStub( 5147 cast<llvm::GlobalValue>(CalleePtr->stripPointerCasts())); 5148 5149 return CGCallee::forDirect(CalleePtr, GD); 5150 } 5151 5152 CGCallee CodeGenFunction::EmitCallee(const Expr *E) { 5153 E = E->IgnoreParens(); 5154 5155 // Look through function-to-pointer decay. 5156 if (auto ICE = dyn_cast<ImplicitCastExpr>(E)) { 5157 if (ICE->getCastKind() == CK_FunctionToPointerDecay || 5158 ICE->getCastKind() == CK_BuiltinFnToFnPtr) { 5159 return EmitCallee(ICE->getSubExpr()); 5160 } 5161 5162 // Resolve direct calls. 5163 } else if (auto DRE = dyn_cast<DeclRefExpr>(E)) { 5164 if (auto FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 5165 return EmitDirectCallee(*this, FD); 5166 } 5167 } else if (auto ME = dyn_cast<MemberExpr>(E)) { 5168 if (auto FD = dyn_cast<FunctionDecl>(ME->getMemberDecl())) { 5169 EmitIgnoredExpr(ME->getBase()); 5170 return EmitDirectCallee(*this, FD); 5171 } 5172 5173 // Look through template substitutions. 5174 } else if (auto NTTP = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) { 5175 return EmitCallee(NTTP->getReplacement()); 5176 5177 // Treat pseudo-destructor calls differently. 5178 } else if (auto PDE = dyn_cast<CXXPseudoDestructorExpr>(E)) { 5179 return CGCallee::forPseudoDestructor(PDE); 5180 } 5181 5182 // Otherwise, we have an indirect reference. 5183 llvm::Value *calleePtr; 5184 QualType functionType; 5185 if (auto ptrType = E->getType()->getAs<PointerType>()) { 5186 calleePtr = EmitScalarExpr(E); 5187 functionType = ptrType->getPointeeType(); 5188 } else { 5189 functionType = E->getType(); 5190 calleePtr = EmitLValue(E, KnownNonNull).getPointer(*this); 5191 } 5192 assert(functionType->isFunctionType()); 5193 5194 GlobalDecl GD; 5195 if (const auto *VD = 5196 dyn_cast_or_null<VarDecl>(E->getReferencedDeclOfCallee())) 5197 GD = GlobalDecl(VD); 5198 5199 CGCalleeInfo calleeInfo(functionType->getAs<FunctionProtoType>(), GD); 5200 CGCallee callee(calleeInfo, calleePtr); 5201 return callee; 5202 } 5203 5204 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) { 5205 // Comma expressions just emit their LHS then their RHS as an l-value. 5206 if (E->getOpcode() == BO_Comma) { 5207 EmitIgnoredExpr(E->getLHS()); 5208 EnsureInsertPoint(); 5209 return EmitLValue(E->getRHS()); 5210 } 5211 5212 if (E->getOpcode() == BO_PtrMemD || 5213 E->getOpcode() == BO_PtrMemI) 5214 return EmitPointerToDataMemberBinaryExpr(E); 5215 5216 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value"); 5217 5218 // Note that in all of these cases, __block variables need the RHS 5219 // evaluated first just in case the variable gets moved by the RHS. 5220 5221 switch (getEvaluationKind(E->getType())) { 5222 case TEK_Scalar: { 5223 switch (E->getLHS()->getType().getObjCLifetime()) { 5224 case Qualifiers::OCL_Strong: 5225 return EmitARCStoreStrong(E, /*ignored*/ false).first; 5226 5227 case Qualifiers::OCL_Autoreleasing: 5228 return EmitARCStoreAutoreleasing(E).first; 5229 5230 // No reason to do any of these differently. 5231 case Qualifiers::OCL_None: 5232 case Qualifiers::OCL_ExplicitNone: 5233 case Qualifiers::OCL_Weak: 5234 break; 5235 } 5236 5237 RValue RV = EmitAnyExpr(E->getRHS()); 5238 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store); 5239 if (RV.isScalar()) 5240 EmitNullabilityCheck(LV, RV.getScalarVal(), E->getExprLoc()); 5241 EmitStoreThroughLValue(RV, LV); 5242 if (getLangOpts().OpenMP) 5243 CGM.getOpenMPRuntime().checkAndEmitLastprivateConditional(*this, 5244 E->getLHS()); 5245 return LV; 5246 } 5247 5248 case TEK_Complex: 5249 return EmitComplexAssignmentLValue(E); 5250 5251 case TEK_Aggregate: 5252 return EmitAggExprToLValue(E); 5253 } 5254 llvm_unreachable("bad evaluation kind"); 5255 } 5256 5257 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) { 5258 RValue RV = EmitCallExpr(E); 5259 5260 if (!RV.isScalar()) 5261 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(), 5262 AlignmentSource::Decl); 5263 5264 assert(E->getCallReturnType(getContext())->isReferenceType() && 5265 "Can't have a scalar return unless the return type is a " 5266 "reference type!"); 5267 5268 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType()); 5269 } 5270 5271 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) { 5272 // FIXME: This shouldn't require another copy. 5273 return EmitAggExprToLValue(E); 5274 } 5275 5276 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) { 5277 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor() 5278 && "binding l-value to type which needs a temporary"); 5279 AggValueSlot Slot = CreateAggTemp(E->getType()); 5280 EmitCXXConstructExpr(E, Slot); 5281 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl); 5282 } 5283 5284 LValue 5285 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) { 5286 return MakeNaturalAlignAddrLValue(EmitCXXTypeidExpr(E), E->getType()); 5287 } 5288 5289 Address CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) { 5290 return CGM.GetAddrOfMSGuidDecl(E->getGuidDecl()) 5291 .withElementType(ConvertType(E->getType())); 5292 } 5293 5294 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) { 5295 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType(), 5296 AlignmentSource::Decl); 5297 } 5298 5299 LValue 5300 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) { 5301 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue"); 5302 Slot.setExternallyDestructed(); 5303 EmitAggExpr(E->getSubExpr(), Slot); 5304 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddress()); 5305 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl); 5306 } 5307 5308 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) { 5309 RValue RV = EmitObjCMessageExpr(E); 5310 5311 if (!RV.isScalar()) 5312 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(), 5313 AlignmentSource::Decl); 5314 5315 assert(E->getMethodDecl()->getReturnType()->isReferenceType() && 5316 "Can't have a scalar return unless the return type is a " 5317 "reference type!"); 5318 5319 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType()); 5320 } 5321 5322 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) { 5323 Address V = 5324 CGM.getObjCRuntime().GetAddrOfSelector(*this, E->getSelector()); 5325 return MakeAddrLValue(V, E->getType(), AlignmentSource::Decl); 5326 } 5327 5328 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface, 5329 const ObjCIvarDecl *Ivar) { 5330 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar); 5331 } 5332 5333 llvm::Value * 5334 CodeGenFunction::EmitIvarOffsetAsPointerDiff(const ObjCInterfaceDecl *Interface, 5335 const ObjCIvarDecl *Ivar) { 5336 llvm::Value *OffsetValue = EmitIvarOffset(Interface, Ivar); 5337 QualType PointerDiffType = getContext().getPointerDiffType(); 5338 return Builder.CreateZExtOrTrunc(OffsetValue, 5339 getTypes().ConvertType(PointerDiffType)); 5340 } 5341 5342 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy, 5343 llvm::Value *BaseValue, 5344 const ObjCIvarDecl *Ivar, 5345 unsigned CVRQualifiers) { 5346 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue, 5347 Ivar, CVRQualifiers); 5348 } 5349 5350 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) { 5351 // FIXME: A lot of the code below could be shared with EmitMemberExpr. 5352 llvm::Value *BaseValue = nullptr; 5353 const Expr *BaseExpr = E->getBase(); 5354 Qualifiers BaseQuals; 5355 QualType ObjectTy; 5356 if (E->isArrow()) { 5357 BaseValue = EmitScalarExpr(BaseExpr); 5358 ObjectTy = BaseExpr->getType()->getPointeeType(); 5359 BaseQuals = ObjectTy.getQualifiers(); 5360 } else { 5361 LValue BaseLV = EmitLValue(BaseExpr); 5362 BaseValue = BaseLV.getPointer(*this); 5363 ObjectTy = BaseExpr->getType(); 5364 BaseQuals = ObjectTy.getQualifiers(); 5365 } 5366 5367 LValue LV = 5368 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(), 5369 BaseQuals.getCVRQualifiers()); 5370 setObjCGCLValueClass(getContext(), E, LV); 5371 return LV; 5372 } 5373 5374 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) { 5375 // Can only get l-value for message expression returning aggregate type 5376 RValue RV = EmitAnyExprToTemp(E); 5377 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(), 5378 AlignmentSource::Decl); 5379 } 5380 5381 RValue CodeGenFunction::EmitCall(QualType CalleeType, const CGCallee &OrigCallee, 5382 const CallExpr *E, ReturnValueSlot ReturnValue, 5383 llvm::Value *Chain) { 5384 // Get the actual function type. The callee type will always be a pointer to 5385 // function type or a block pointer type. 5386 assert(CalleeType->isFunctionPointerType() && 5387 "Call must have function pointer type!"); 5388 5389 const Decl *TargetDecl = 5390 OrigCallee.getAbstractInfo().getCalleeDecl().getDecl(); 5391 5392 assert((!isa_and_present<FunctionDecl>(TargetDecl) || 5393 !cast<FunctionDecl>(TargetDecl)->isImmediateFunction()) && 5394 "trying to emit a call to an immediate function"); 5395 5396 CalleeType = getContext().getCanonicalType(CalleeType); 5397 5398 auto PointeeType = cast<PointerType>(CalleeType)->getPointeeType(); 5399 5400 CGCallee Callee = OrigCallee; 5401 5402 if (SanOpts.has(SanitizerKind::Function) && 5403 (!TargetDecl || !isa<FunctionDecl>(TargetDecl)) && 5404 !isa<FunctionNoProtoType>(PointeeType)) { 5405 if (llvm::Constant *PrefixSig = 5406 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) { 5407 SanitizerScope SanScope(this); 5408 auto *TypeHash = getUBSanFunctionTypeHash(PointeeType); 5409 5410 llvm::Type *PrefixSigType = PrefixSig->getType(); 5411 llvm::StructType *PrefixStructTy = llvm::StructType::get( 5412 CGM.getLLVMContext(), {PrefixSigType, Int32Ty}, /*isPacked=*/true); 5413 5414 llvm::Value *CalleePtr = Callee.getFunctionPointer(); 5415 5416 // On 32-bit Arm, the low bit of a function pointer indicates whether 5417 // it's using the Arm or Thumb instruction set. The actual first 5418 // instruction lives at the same address either way, so we must clear 5419 // that low bit before using the function address to find the prefix 5420 // structure. 5421 // 5422 // This applies to both Arm and Thumb target triples, because 5423 // either one could be used in an interworking context where it 5424 // might be passed function pointers of both types. 5425 llvm::Value *AlignedCalleePtr; 5426 if (CGM.getTriple().isARM() || CGM.getTriple().isThumb()) { 5427 llvm::Value *CalleeAddress = 5428 Builder.CreatePtrToInt(CalleePtr, IntPtrTy); 5429 llvm::Value *Mask = llvm::ConstantInt::get(IntPtrTy, ~1); 5430 llvm::Value *AlignedCalleeAddress = 5431 Builder.CreateAnd(CalleeAddress, Mask); 5432 AlignedCalleePtr = 5433 Builder.CreateIntToPtr(AlignedCalleeAddress, CalleePtr->getType()); 5434 } else { 5435 AlignedCalleePtr = CalleePtr; 5436 } 5437 5438 llvm::Value *CalleePrefixStruct = AlignedCalleePtr; 5439 llvm::Value *CalleeSigPtr = 5440 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, -1, 0); 5441 llvm::Value *CalleeSig = 5442 Builder.CreateAlignedLoad(PrefixSigType, CalleeSigPtr, getIntAlign()); 5443 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig); 5444 5445 llvm::BasicBlock *Cont = createBasicBlock("cont"); 5446 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck"); 5447 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont); 5448 5449 EmitBlock(TypeCheck); 5450 llvm::Value *CalleeTypeHash = Builder.CreateAlignedLoad( 5451 Int32Ty, 5452 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, -1, 1), 5453 getPointerAlign()); 5454 llvm::Value *CalleeTypeHashMatch = 5455 Builder.CreateICmpEQ(CalleeTypeHash, TypeHash); 5456 llvm::Constant *StaticData[] = {EmitCheckSourceLocation(E->getBeginLoc()), 5457 EmitCheckTypeDescriptor(CalleeType)}; 5458 EmitCheck(std::make_pair(CalleeTypeHashMatch, SanitizerKind::Function), 5459 SanitizerHandler::FunctionTypeMismatch, StaticData, 5460 {CalleePtr}); 5461 5462 Builder.CreateBr(Cont); 5463 EmitBlock(Cont); 5464 } 5465 } 5466 5467 const auto *FnType = cast<FunctionType>(PointeeType); 5468 5469 // If we are checking indirect calls and this call is indirect, check that the 5470 // function pointer is a member of the bit set for the function type. 5471 if (SanOpts.has(SanitizerKind::CFIICall) && 5472 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) { 5473 SanitizerScope SanScope(this); 5474 EmitSanitizerStatReport(llvm::SanStat_CFI_ICall); 5475 5476 llvm::Metadata *MD; 5477 if (CGM.getCodeGenOpts().SanitizeCfiICallGeneralizePointers) 5478 MD = CGM.CreateMetadataIdentifierGeneralized(QualType(FnType, 0)); 5479 else 5480 MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0)); 5481 5482 llvm::Value *TypeId = llvm::MetadataAsValue::get(getLLVMContext(), MD); 5483 5484 llvm::Value *CalleePtr = Callee.getFunctionPointer(); 5485 llvm::Value *TypeTest = Builder.CreateCall( 5486 CGM.getIntrinsic(llvm::Intrinsic::type_test), {CalleePtr, TypeId}); 5487 5488 auto CrossDsoTypeId = CGM.CreateCrossDsoCfiTypeId(MD); 5489 llvm::Constant *StaticData[] = { 5490 llvm::ConstantInt::get(Int8Ty, CFITCK_ICall), 5491 EmitCheckSourceLocation(E->getBeginLoc()), 5492 EmitCheckTypeDescriptor(QualType(FnType, 0)), 5493 }; 5494 if (CGM.getCodeGenOpts().SanitizeCfiCrossDso && CrossDsoTypeId) { 5495 EmitCfiSlowPathCheck(SanitizerKind::CFIICall, TypeTest, CrossDsoTypeId, 5496 CalleePtr, StaticData); 5497 } else { 5498 EmitCheck(std::make_pair(TypeTest, SanitizerKind::CFIICall), 5499 SanitizerHandler::CFICheckFail, StaticData, 5500 {CalleePtr, llvm::UndefValue::get(IntPtrTy)}); 5501 } 5502 } 5503 5504 CallArgList Args; 5505 if (Chain) 5506 Args.add(RValue::get(Chain), CGM.getContext().VoidPtrTy); 5507 5508 // C++17 requires that we evaluate arguments to a call using assignment syntax 5509 // right-to-left, and that we evaluate arguments to certain other operators 5510 // left-to-right. Note that we allow this to override the order dictated by 5511 // the calling convention on the MS ABI, which means that parameter 5512 // destruction order is not necessarily reverse construction order. 5513 // FIXME: Revisit this based on C++ committee response to unimplementability. 5514 EvaluationOrder Order = EvaluationOrder::Default; 5515 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(E)) { 5516 if (OCE->isAssignmentOp()) 5517 Order = EvaluationOrder::ForceRightToLeft; 5518 else { 5519 switch (OCE->getOperator()) { 5520 case OO_LessLess: 5521 case OO_GreaterGreater: 5522 case OO_AmpAmp: 5523 case OO_PipePipe: 5524 case OO_Comma: 5525 case OO_ArrowStar: 5526 Order = EvaluationOrder::ForceLeftToRight; 5527 break; 5528 default: 5529 break; 5530 } 5531 } 5532 } 5533 5534 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), E->arguments(), 5535 E->getDirectCallee(), /*ParamsToSkip*/ 0, Order); 5536 5537 const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeFreeFunctionCall( 5538 Args, FnType, /*ChainCall=*/Chain); 5539 5540 // C99 6.5.2.2p6: 5541 // If the expression that denotes the called function has a type 5542 // that does not include a prototype, [the default argument 5543 // promotions are performed]. If the number of arguments does not 5544 // equal the number of parameters, the behavior is undefined. If 5545 // the function is defined with a type that includes a prototype, 5546 // and either the prototype ends with an ellipsis (, ...) or the 5547 // types of the arguments after promotion are not compatible with 5548 // the types of the parameters, the behavior is undefined. If the 5549 // function is defined with a type that does not include a 5550 // prototype, and the types of the arguments after promotion are 5551 // not compatible with those of the parameters after promotion, 5552 // the behavior is undefined [except in some trivial cases]. 5553 // That is, in the general case, we should assume that a call 5554 // through an unprototyped function type works like a *non-variadic* 5555 // call. The way we make this work is to cast to the exact type 5556 // of the promoted arguments. 5557 // 5558 // Chain calls use this same code path to add the invisible chain parameter 5559 // to the function type. 5560 if (isa<FunctionNoProtoType>(FnType) || Chain) { 5561 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo); 5562 int AS = Callee.getFunctionPointer()->getType()->getPointerAddressSpace(); 5563 CalleeTy = CalleeTy->getPointerTo(AS); 5564 5565 llvm::Value *CalleePtr = Callee.getFunctionPointer(); 5566 CalleePtr = Builder.CreateBitCast(CalleePtr, CalleeTy, "callee.knr.cast"); 5567 Callee.setFunctionPointer(CalleePtr); 5568 } 5569 5570 // HIP function pointer contains kernel handle when it is used in triple 5571 // chevron. The kernel stub needs to be loaded from kernel handle and used 5572 // as callee. 5573 if (CGM.getLangOpts().HIP && !CGM.getLangOpts().CUDAIsDevice && 5574 isa<CUDAKernelCallExpr>(E) && 5575 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) { 5576 llvm::Value *Handle = Callee.getFunctionPointer(); 5577 auto *Stub = Builder.CreateLoad( 5578 Address(Handle, Handle->getType(), CGM.getPointerAlign())); 5579 Callee.setFunctionPointer(Stub); 5580 } 5581 llvm::CallBase *CallOrInvoke = nullptr; 5582 RValue Call = EmitCall(FnInfo, Callee, ReturnValue, Args, &CallOrInvoke, 5583 E == MustTailCall, E->getExprLoc()); 5584 5585 // Generate function declaration DISuprogram in order to be used 5586 // in debug info about call sites. 5587 if (CGDebugInfo *DI = getDebugInfo()) { 5588 if (auto *CalleeDecl = dyn_cast_or_null<FunctionDecl>(TargetDecl)) { 5589 FunctionArgList Args; 5590 QualType ResTy = BuildFunctionArgList(CalleeDecl, Args); 5591 DI->EmitFuncDeclForCallSite(CallOrInvoke, 5592 DI->getFunctionType(CalleeDecl, ResTy, Args), 5593 CalleeDecl); 5594 } 5595 } 5596 5597 return Call; 5598 } 5599 5600 LValue CodeGenFunction:: 5601 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) { 5602 Address BaseAddr = Address::invalid(); 5603 if (E->getOpcode() == BO_PtrMemI) { 5604 BaseAddr = EmitPointerWithAlignment(E->getLHS()); 5605 } else { 5606 BaseAddr = EmitLValue(E->getLHS()).getAddress(*this); 5607 } 5608 5609 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS()); 5610 const auto *MPT = E->getRHS()->getType()->castAs<MemberPointerType>(); 5611 5612 LValueBaseInfo BaseInfo; 5613 TBAAAccessInfo TBAAInfo; 5614 Address MemberAddr = 5615 EmitCXXMemberDataPointerAddress(E, BaseAddr, OffsetV, MPT, &BaseInfo, 5616 &TBAAInfo); 5617 5618 return MakeAddrLValue(MemberAddr, MPT->getPointeeType(), BaseInfo, TBAAInfo); 5619 } 5620 5621 /// Given the address of a temporary variable, produce an r-value of 5622 /// its type. 5623 RValue CodeGenFunction::convertTempToRValue(Address addr, 5624 QualType type, 5625 SourceLocation loc) { 5626 LValue lvalue = MakeAddrLValue(addr, type, AlignmentSource::Decl); 5627 switch (getEvaluationKind(type)) { 5628 case TEK_Complex: 5629 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc)); 5630 case TEK_Aggregate: 5631 return lvalue.asAggregateRValue(*this); 5632 case TEK_Scalar: 5633 return RValue::get(EmitLoadOfScalar(lvalue, loc)); 5634 } 5635 llvm_unreachable("bad evaluation kind"); 5636 } 5637 5638 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) { 5639 assert(Val->getType()->isFPOrFPVectorTy()); 5640 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val)) 5641 return; 5642 5643 llvm::MDBuilder MDHelper(getLLVMContext()); 5644 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy); 5645 5646 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node); 5647 } 5648 5649 void CodeGenFunction::SetSqrtFPAccuracy(llvm::Value *Val) { 5650 llvm::Type *EltTy = Val->getType()->getScalarType(); 5651 if (!EltTy->isFloatTy()) 5652 return; 5653 5654 if ((getLangOpts().OpenCL && 5655 !CGM.getCodeGenOpts().OpenCLCorrectlyRoundedDivSqrt) || 5656 (getLangOpts().HIP && getLangOpts().CUDAIsDevice && 5657 !CGM.getCodeGenOpts().HIPCorrectlyRoundedDivSqrt)) { 5658 // OpenCL v1.1 s7.4: minimum accuracy of single precision / is 3ulp 5659 // 5660 // OpenCL v1.2 s5.6.4.2: The -cl-fp32-correctly-rounded-divide-sqrt 5661 // build option allows an application to specify that single precision 5662 // floating-point divide (x/y and 1/x) and sqrt used in the program 5663 // source are correctly rounded. 5664 // 5665 // TODO: CUDA has a prec-sqrt flag 5666 SetFPAccuracy(Val, 3.0f); 5667 } 5668 } 5669 5670 void CodeGenFunction::SetDivFPAccuracy(llvm::Value *Val) { 5671 llvm::Type *EltTy = Val->getType()->getScalarType(); 5672 if (!EltTy->isFloatTy()) 5673 return; 5674 5675 if ((getLangOpts().OpenCL && 5676 !CGM.getCodeGenOpts().OpenCLCorrectlyRoundedDivSqrt) || 5677 (getLangOpts().HIP && getLangOpts().CUDAIsDevice && 5678 !CGM.getCodeGenOpts().HIPCorrectlyRoundedDivSqrt)) { 5679 // OpenCL v1.1 s7.4: minimum accuracy of single precision / is 2.5ulp 5680 // 5681 // OpenCL v1.2 s5.6.4.2: The -cl-fp32-correctly-rounded-divide-sqrt 5682 // build option allows an application to specify that single precision 5683 // floating-point divide (x/y and 1/x) and sqrt used in the program 5684 // source are correctly rounded. 5685 // 5686 // TODO: CUDA has a prec-div flag 5687 SetFPAccuracy(Val, 2.5f); 5688 } 5689 } 5690 5691 namespace { 5692 struct LValueOrRValue { 5693 LValue LV; 5694 RValue RV; 5695 }; 5696 } 5697 5698 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF, 5699 const PseudoObjectExpr *E, 5700 bool forLValue, 5701 AggValueSlot slot) { 5702 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques; 5703 5704 // Find the result expression, if any. 5705 const Expr *resultExpr = E->getResultExpr(); 5706 LValueOrRValue result; 5707 5708 for (PseudoObjectExpr::const_semantics_iterator 5709 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) { 5710 const Expr *semantic = *i; 5711 5712 // If this semantic expression is an opaque value, bind it 5713 // to the result of its source expression. 5714 if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) { 5715 // Skip unique OVEs. 5716 if (ov->isUnique()) { 5717 assert(ov != resultExpr && 5718 "A unique OVE cannot be used as the result expression"); 5719 continue; 5720 } 5721 5722 // If this is the result expression, we may need to evaluate 5723 // directly into the slot. 5724 typedef CodeGenFunction::OpaqueValueMappingData OVMA; 5725 OVMA opaqueData; 5726 if (ov == resultExpr && ov->isPRValue() && !forLValue && 5727 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) { 5728 CGF.EmitAggExpr(ov->getSourceExpr(), slot); 5729 LValue LV = CGF.MakeAddrLValue(slot.getAddress(), ov->getType(), 5730 AlignmentSource::Decl); 5731 opaqueData = OVMA::bind(CGF, ov, LV); 5732 result.RV = slot.asRValue(); 5733 5734 // Otherwise, emit as normal. 5735 } else { 5736 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr()); 5737 5738 // If this is the result, also evaluate the result now. 5739 if (ov == resultExpr) { 5740 if (forLValue) 5741 result.LV = CGF.EmitLValue(ov); 5742 else 5743 result.RV = CGF.EmitAnyExpr(ov, slot); 5744 } 5745 } 5746 5747 opaques.push_back(opaqueData); 5748 5749 // Otherwise, if the expression is the result, evaluate it 5750 // and remember the result. 5751 } else if (semantic == resultExpr) { 5752 if (forLValue) 5753 result.LV = CGF.EmitLValue(semantic); 5754 else 5755 result.RV = CGF.EmitAnyExpr(semantic, slot); 5756 5757 // Otherwise, evaluate the expression in an ignored context. 5758 } else { 5759 CGF.EmitIgnoredExpr(semantic); 5760 } 5761 } 5762 5763 // Unbind all the opaques now. 5764 for (unsigned i = 0, e = opaques.size(); i != e; ++i) 5765 opaques[i].unbind(CGF); 5766 5767 return result; 5768 } 5769 5770 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E, 5771 AggValueSlot slot) { 5772 return emitPseudoObjectExpr(*this, E, false, slot).RV; 5773 } 5774 5775 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) { 5776 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV; 5777 } 5778