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 //===--------------------------------------------------------------------===// 55 // Miscellaneous Helper Methods 56 //===--------------------------------------------------------------------===// 57 58 /// CreateTempAlloca - This creates a alloca and inserts it into the entry 59 /// block. 60 Address CodeGenFunction::CreateTempAllocaWithoutCast(llvm::Type *Ty, 61 CharUnits Align, 62 const Twine &Name, 63 llvm::Value *ArraySize) { 64 auto Alloca = CreateTempAlloca(Ty, Name, ArraySize); 65 Alloca->setAlignment(Align.getAsAlign()); 66 return Address(Alloca, Ty, Align, KnownNonNull); 67 } 68 69 /// CreateTempAlloca - This creates a alloca and inserts it into the entry 70 /// block. The alloca is casted to default address space if necessary. 71 Address CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, CharUnits Align, 72 const Twine &Name, 73 llvm::Value *ArraySize, 74 Address *AllocaAddr) { 75 auto Alloca = CreateTempAllocaWithoutCast(Ty, Align, Name, ArraySize); 76 if (AllocaAddr) 77 *AllocaAddr = Alloca; 78 llvm::Value *V = Alloca.getPointer(); 79 // Alloca always returns a pointer in alloca address space, which may 80 // be different from the type defined by the language. For example, 81 // in C++ the auto variables are in the default address space. Therefore 82 // cast alloca to the default address space when necessary. 83 if (getASTAllocaAddressSpace() != LangAS::Default) { 84 auto DestAddrSpace = getContext().getTargetAddressSpace(LangAS::Default); 85 llvm::IRBuilderBase::InsertPointGuard IPG(Builder); 86 // When ArraySize is nullptr, alloca is inserted at AllocaInsertPt, 87 // otherwise alloca is inserted at the current insertion point of the 88 // builder. 89 if (!ArraySize) 90 Builder.SetInsertPoint(getPostAllocaInsertPoint()); 91 V = getTargetHooks().performAddrSpaceCast( 92 *this, V, getASTAllocaAddressSpace(), LangAS::Default, 93 Ty->getPointerTo(DestAddrSpace), /*non-null*/ true); 94 } 95 96 return Address(V, Ty, Align, KnownNonNull); 97 } 98 99 /// CreateTempAlloca - This creates an alloca and inserts it into the entry 100 /// block if \p ArraySize is nullptr, otherwise inserts it at the current 101 /// insertion point of the builder. 102 llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, 103 const Twine &Name, 104 llvm::Value *ArraySize) { 105 if (ArraySize) 106 return Builder.CreateAlloca(Ty, ArraySize, Name); 107 return new llvm::AllocaInst(Ty, CGM.getDataLayout().getAllocaAddrSpace(), 108 ArraySize, Name, AllocaInsertPt); 109 } 110 111 /// CreateDefaultAlignTempAlloca - This creates an alloca with the 112 /// default alignment of the corresponding LLVM type, which is *not* 113 /// guaranteed to be related in any way to the expected alignment of 114 /// an AST type that might have been lowered to Ty. 115 Address CodeGenFunction::CreateDefaultAlignTempAlloca(llvm::Type *Ty, 116 const Twine &Name) { 117 CharUnits Align = 118 CharUnits::fromQuantity(CGM.getDataLayout().getPrefTypeAlign(Ty)); 119 return CreateTempAlloca(Ty, Align, Name); 120 } 121 122 Address CodeGenFunction::CreateIRTemp(QualType Ty, const Twine &Name) { 123 CharUnits Align = getContext().getTypeAlignInChars(Ty); 124 return CreateTempAlloca(ConvertType(Ty), Align, Name); 125 } 126 127 Address CodeGenFunction::CreateMemTemp(QualType Ty, const Twine &Name, 128 Address *Alloca) { 129 // FIXME: Should we prefer the preferred type alignment here? 130 return CreateMemTemp(Ty, getContext().getTypeAlignInChars(Ty), Name, Alloca); 131 } 132 133 Address CodeGenFunction::CreateMemTemp(QualType Ty, CharUnits Align, 134 const Twine &Name, Address *Alloca) { 135 Address Result = CreateTempAlloca(ConvertTypeForMem(Ty), Align, Name, 136 /*ArraySize=*/nullptr, Alloca); 137 138 if (Ty->isConstantMatrixType()) { 139 auto *ArrayTy = cast<llvm::ArrayType>(Result.getElementType()); 140 auto *VectorTy = llvm::FixedVectorType::get(ArrayTy->getElementType(), 141 ArrayTy->getNumElements()); 142 143 Result = Address( 144 Builder.CreateBitCast(Result.getPointer(), VectorTy->getPointerTo()), 145 VectorTy, Result.getAlignment(), KnownNonNull); 146 } 147 return Result; 148 } 149 150 Address CodeGenFunction::CreateMemTempWithoutCast(QualType Ty, CharUnits Align, 151 const Twine &Name) { 152 return CreateTempAllocaWithoutCast(ConvertTypeForMem(Ty), Align, Name); 153 } 154 155 Address CodeGenFunction::CreateMemTempWithoutCast(QualType Ty, 156 const Twine &Name) { 157 return CreateMemTempWithoutCast(Ty, getContext().getTypeAlignInChars(Ty), 158 Name); 159 } 160 161 /// EvaluateExprAsBool - Perform the usual unary conversions on the specified 162 /// expression and compare the result against zero, returning an Int1Ty value. 163 llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) { 164 PGO.setCurrentStmt(E); 165 if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) { 166 llvm::Value *MemPtr = EmitScalarExpr(E); 167 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT); 168 } 169 170 QualType BoolTy = getContext().BoolTy; 171 SourceLocation Loc = E->getExprLoc(); 172 CGFPOptionsRAII FPOptsRAII(*this, E); 173 if (!E->getType()->isAnyComplexType()) 174 return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy, Loc); 175 176 return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(), BoolTy, 177 Loc); 178 } 179 180 /// EmitIgnoredExpr - Emit code to compute the specified expression, 181 /// ignoring the result. 182 void CodeGenFunction::EmitIgnoredExpr(const Expr *E) { 183 if (E->isPRValue()) 184 return (void)EmitAnyExpr(E, AggValueSlot::ignored(), true); 185 186 // if this is a bitfield-resulting conditional operator, we can special case 187 // emit this. The normal 'EmitLValue' version of this is particularly 188 // difficult to codegen for, since creating a single "LValue" for two 189 // different sized arguments here is not particularly doable. 190 if (const auto *CondOp = dyn_cast<AbstractConditionalOperator>( 191 E->IgnoreParenNoopCasts(getContext()))) { 192 if (CondOp->getObjectKind() == OK_BitField) 193 return EmitIgnoredConditionalOperator(CondOp); 194 } 195 196 // Just emit it as an l-value and drop the result. 197 EmitLValue(E); 198 } 199 200 /// EmitAnyExpr - Emit code to compute the specified expression which 201 /// can have any type. The result is returned as an RValue struct. 202 /// If this is an aggregate expression, AggSlot indicates where the 203 /// result should be returned. 204 RValue CodeGenFunction::EmitAnyExpr(const Expr *E, 205 AggValueSlot aggSlot, 206 bool ignoreResult) { 207 switch (getEvaluationKind(E->getType())) { 208 case TEK_Scalar: 209 return RValue::get(EmitScalarExpr(E, ignoreResult)); 210 case TEK_Complex: 211 return RValue::getComplex(EmitComplexExpr(E, ignoreResult, ignoreResult)); 212 case TEK_Aggregate: 213 if (!ignoreResult && aggSlot.isIgnored()) 214 aggSlot = CreateAggTemp(E->getType(), "agg-temp"); 215 EmitAggExpr(E, aggSlot); 216 return aggSlot.asRValue(); 217 } 218 llvm_unreachable("bad evaluation kind"); 219 } 220 221 /// EmitAnyExprToTemp - Similar to EmitAnyExpr(), however, the result will 222 /// always be accessible even if no aggregate location is provided. 223 RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) { 224 AggValueSlot AggSlot = AggValueSlot::ignored(); 225 226 if (hasAggregateEvaluationKind(E->getType())) 227 AggSlot = CreateAggTemp(E->getType(), "agg.tmp"); 228 return EmitAnyExpr(E, AggSlot); 229 } 230 231 /// EmitAnyExprToMem - Evaluate an expression into a given memory 232 /// location. 233 void CodeGenFunction::EmitAnyExprToMem(const Expr *E, 234 Address Location, 235 Qualifiers Quals, 236 bool IsInit) { 237 // FIXME: This function should take an LValue as an argument. 238 switch (getEvaluationKind(E->getType())) { 239 case TEK_Complex: 240 EmitComplexExprIntoLValue(E, MakeAddrLValue(Location, E->getType()), 241 /*isInit*/ false); 242 return; 243 244 case TEK_Aggregate: { 245 EmitAggExpr(E, AggValueSlot::forAddr(Location, Quals, 246 AggValueSlot::IsDestructed_t(IsInit), 247 AggValueSlot::DoesNotNeedGCBarriers, 248 AggValueSlot::IsAliased_t(!IsInit), 249 AggValueSlot::MayOverlap)); 250 return; 251 } 252 253 case TEK_Scalar: { 254 RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false)); 255 LValue LV = MakeAddrLValue(Location, E->getType()); 256 EmitStoreThroughLValue(RV, LV); 257 return; 258 } 259 } 260 llvm_unreachable("bad evaluation kind"); 261 } 262 263 static void 264 pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M, 265 const Expr *E, Address ReferenceTemporary) { 266 // Objective-C++ ARC: 267 // If we are binding a reference to a temporary that has ownership, we 268 // need to perform retain/release operations on the temporary. 269 // 270 // FIXME: This should be looking at E, not M. 271 if (auto Lifetime = M->getType().getObjCLifetime()) { 272 switch (Lifetime) { 273 case Qualifiers::OCL_None: 274 case Qualifiers::OCL_ExplicitNone: 275 // Carry on to normal cleanup handling. 276 break; 277 278 case Qualifiers::OCL_Autoreleasing: 279 // Nothing to do; cleaned up by an autorelease pool. 280 return; 281 282 case Qualifiers::OCL_Strong: 283 case Qualifiers::OCL_Weak: 284 switch (StorageDuration Duration = M->getStorageDuration()) { 285 case SD_Static: 286 // Note: we intentionally do not register a cleanup to release 287 // the object on program termination. 288 return; 289 290 case SD_Thread: 291 // FIXME: We should probably register a cleanup in this case. 292 return; 293 294 case SD_Automatic: 295 case SD_FullExpression: 296 CodeGenFunction::Destroyer *Destroy; 297 CleanupKind CleanupKind; 298 if (Lifetime == Qualifiers::OCL_Strong) { 299 const ValueDecl *VD = M->getExtendingDecl(); 300 bool Precise = 301 VD && isa<VarDecl>(VD) && VD->hasAttr<ObjCPreciseLifetimeAttr>(); 302 CleanupKind = CGF.getARCCleanupKind(); 303 Destroy = Precise ? &CodeGenFunction::destroyARCStrongPrecise 304 : &CodeGenFunction::destroyARCStrongImprecise; 305 } else { 306 // __weak objects always get EH cleanups; otherwise, exceptions 307 // could cause really nasty crashes instead of mere leaks. 308 CleanupKind = NormalAndEHCleanup; 309 Destroy = &CodeGenFunction::destroyARCWeak; 310 } 311 if (Duration == SD_FullExpression) 312 CGF.pushDestroy(CleanupKind, ReferenceTemporary, 313 M->getType(), *Destroy, 314 CleanupKind & EHCleanup); 315 else 316 CGF.pushLifetimeExtendedDestroy(CleanupKind, ReferenceTemporary, 317 M->getType(), 318 *Destroy, CleanupKind & EHCleanup); 319 return; 320 321 case SD_Dynamic: 322 llvm_unreachable("temporary cannot have dynamic storage duration"); 323 } 324 llvm_unreachable("unknown storage duration"); 325 } 326 } 327 328 CXXDestructorDecl *ReferenceTemporaryDtor = nullptr; 329 if (const RecordType *RT = 330 E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) { 331 // Get the destructor for the reference temporary. 332 auto *ClassDecl = cast<CXXRecordDecl>(RT->getDecl()); 333 if (!ClassDecl->hasTrivialDestructor()) 334 ReferenceTemporaryDtor = ClassDecl->getDestructor(); 335 } 336 337 if (!ReferenceTemporaryDtor) 338 return; 339 340 // Call the destructor for the temporary. 341 switch (M->getStorageDuration()) { 342 case SD_Static: 343 case SD_Thread: { 344 llvm::FunctionCallee CleanupFn; 345 llvm::Constant *CleanupArg; 346 if (E->getType()->isArrayType()) { 347 CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper( 348 ReferenceTemporary, E->getType(), 349 CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions, 350 dyn_cast_or_null<VarDecl>(M->getExtendingDecl())); 351 CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy); 352 } else { 353 CleanupFn = CGF.CGM.getAddrAndTypeOfCXXStructor( 354 GlobalDecl(ReferenceTemporaryDtor, Dtor_Complete)); 355 CleanupArg = cast<llvm::Constant>(ReferenceTemporary.getPointer()); 356 } 357 CGF.CGM.getCXXABI().registerGlobalDtor( 358 CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg); 359 break; 360 } 361 362 case SD_FullExpression: 363 CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(), 364 CodeGenFunction::destroyCXXObject, 365 CGF.getLangOpts().Exceptions); 366 break; 367 368 case SD_Automatic: 369 CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup, 370 ReferenceTemporary, E->getType(), 371 CodeGenFunction::destroyCXXObject, 372 CGF.getLangOpts().Exceptions); 373 break; 374 375 case SD_Dynamic: 376 llvm_unreachable("temporary cannot have dynamic storage duration"); 377 } 378 } 379 380 static Address createReferenceTemporary(CodeGenFunction &CGF, 381 const MaterializeTemporaryExpr *M, 382 const Expr *Inner, 383 Address *Alloca = nullptr) { 384 auto &TCG = CGF.getTargetHooks(); 385 switch (M->getStorageDuration()) { 386 case SD_FullExpression: 387 case SD_Automatic: { 388 // If we have a constant temporary array or record try to promote it into a 389 // constant global under the same rules a normal constant would've been 390 // promoted. This is easier on the optimizer and generally emits fewer 391 // instructions. 392 QualType Ty = Inner->getType(); 393 if (CGF.CGM.getCodeGenOpts().MergeAllConstants && 394 (Ty->isArrayType() || Ty->isRecordType()) && 395 CGF.CGM.isTypeConstant(Ty, true, false)) 396 if (auto Init = ConstantEmitter(CGF).tryEmitAbstract(Inner, Ty)) { 397 auto AS = CGF.CGM.GetGlobalConstantAddressSpace(); 398 auto *GV = new llvm::GlobalVariable( 399 CGF.CGM.getModule(), Init->getType(), /*isConstant=*/true, 400 llvm::GlobalValue::PrivateLinkage, Init, ".ref.tmp", nullptr, 401 llvm::GlobalValue::NotThreadLocal, 402 CGF.getContext().getTargetAddressSpace(AS)); 403 CharUnits alignment = CGF.getContext().getTypeAlignInChars(Ty); 404 GV->setAlignment(alignment.getAsAlign()); 405 llvm::Constant *C = GV; 406 if (AS != LangAS::Default) 407 C = TCG.performAddrSpaceCast( 408 CGF.CGM, GV, AS, LangAS::Default, 409 GV->getValueType()->getPointerTo( 410 CGF.getContext().getTargetAddressSpace(LangAS::Default))); 411 // FIXME: Should we put the new global into a COMDAT? 412 return Address(C, GV->getValueType(), alignment); 413 } 414 return CGF.CreateMemTemp(Ty, "ref.tmp", Alloca); 415 } 416 case SD_Thread: 417 case SD_Static: 418 return CGF.CGM.GetAddrOfGlobalTemporary(M, Inner); 419 420 case SD_Dynamic: 421 llvm_unreachable("temporary can't have dynamic storage duration"); 422 } 423 llvm_unreachable("unknown storage duration"); 424 } 425 426 /// Helper method to check if the underlying ABI is AAPCS 427 static bool isAAPCS(const TargetInfo &TargetInfo) { 428 return TargetInfo.getABI().startswith("aapcs"); 429 } 430 431 LValue CodeGenFunction:: 432 EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) { 433 const Expr *E = M->getSubExpr(); 434 435 assert((!M->getExtendingDecl() || !isa<VarDecl>(M->getExtendingDecl()) || 436 !cast<VarDecl>(M->getExtendingDecl())->isARCPseudoStrong()) && 437 "Reference should never be pseudo-strong!"); 438 439 // FIXME: ideally this would use EmitAnyExprToMem, however, we cannot do so 440 // as that will cause the lifetime adjustment to be lost for ARC 441 auto ownership = M->getType().getObjCLifetime(); 442 if (ownership != Qualifiers::OCL_None && 443 ownership != Qualifiers::OCL_ExplicitNone) { 444 Address Object = createReferenceTemporary(*this, M, E); 445 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) { 446 llvm::Type *Ty = ConvertTypeForMem(E->getType()); 447 Object = Address(llvm::ConstantExpr::getBitCast( 448 Var, Ty->getPointerTo(Object.getAddressSpace())), 449 Ty, Object.getAlignment()); 450 451 // createReferenceTemporary will promote the temporary to a global with a 452 // constant initializer if it can. It can only do this to a value of 453 // ARC-manageable type if the value is global and therefore "immune" to 454 // ref-counting operations. Therefore we have no need to emit either a 455 // dynamic initialization or a cleanup and we can just return the address 456 // of the temporary. 457 if (Var->hasInitializer()) 458 return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl); 459 460 Var->setInitializer(CGM.EmitNullConstant(E->getType())); 461 } 462 LValue RefTempDst = MakeAddrLValue(Object, M->getType(), 463 AlignmentSource::Decl); 464 465 switch (getEvaluationKind(E->getType())) { 466 default: llvm_unreachable("expected scalar or aggregate expression"); 467 case TEK_Scalar: 468 EmitScalarInit(E, M->getExtendingDecl(), RefTempDst, false); 469 break; 470 case TEK_Aggregate: { 471 EmitAggExpr(E, AggValueSlot::forAddr(Object, 472 E->getType().getQualifiers(), 473 AggValueSlot::IsDestructed, 474 AggValueSlot::DoesNotNeedGCBarriers, 475 AggValueSlot::IsNotAliased, 476 AggValueSlot::DoesNotOverlap)); 477 break; 478 } 479 } 480 481 pushTemporaryCleanup(*this, M, E, Object); 482 return RefTempDst; 483 } 484 485 SmallVector<const Expr *, 2> CommaLHSs; 486 SmallVector<SubobjectAdjustment, 2> Adjustments; 487 E = E->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); 488 489 for (const auto &Ignored : CommaLHSs) 490 EmitIgnoredExpr(Ignored); 491 492 if (const auto *opaque = dyn_cast<OpaqueValueExpr>(E)) { 493 if (opaque->getType()->isRecordType()) { 494 assert(Adjustments.empty()); 495 return EmitOpaqueValueLValue(opaque); 496 } 497 } 498 499 // Create and initialize the reference temporary. 500 Address Alloca = Address::invalid(); 501 Address Object = createReferenceTemporary(*this, M, E, &Alloca); 502 if (auto *Var = dyn_cast<llvm::GlobalVariable>( 503 Object.getPointer()->stripPointerCasts())) { 504 llvm::Type *TemporaryType = ConvertTypeForMem(E->getType()); 505 Object = Address(llvm::ConstantExpr::getBitCast( 506 cast<llvm::Constant>(Object.getPointer()), 507 TemporaryType->getPointerTo()), 508 TemporaryType, 509 Object.getAlignment()); 510 // If the temporary is a global and has a constant initializer or is a 511 // constant temporary that we promoted to a global, we may have already 512 // initialized it. 513 if (!Var->hasInitializer()) { 514 Var->setInitializer(CGM.EmitNullConstant(E->getType())); 515 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true); 516 } 517 } else { 518 switch (M->getStorageDuration()) { 519 case SD_Automatic: 520 if (auto *Size = EmitLifetimeStart( 521 CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()), 522 Alloca.getPointer())) { 523 pushCleanupAfterFullExpr<CallLifetimeEnd>(NormalEHLifetimeMarker, 524 Alloca, Size); 525 } 526 break; 527 528 case SD_FullExpression: { 529 if (!ShouldEmitLifetimeMarkers) 530 break; 531 532 // Avoid creating a conditional cleanup just to hold an llvm.lifetime.end 533 // marker. Instead, start the lifetime of a conditional temporary earlier 534 // so that it's unconditional. Don't do this with sanitizers which need 535 // more precise lifetime marks. However when inside an "await.suspend" 536 // block, we should always avoid conditional cleanup because it creates 537 // boolean marker that lives across await_suspend, which can destroy coro 538 // frame. 539 ConditionalEvaluation *OldConditional = nullptr; 540 CGBuilderTy::InsertPoint OldIP; 541 if (isInConditionalBranch() && !E->getType().isDestructedType() && 542 ((!SanOpts.has(SanitizerKind::HWAddress) && 543 !SanOpts.has(SanitizerKind::Memory) && 544 !CGM.getCodeGenOpts().SanitizeAddressUseAfterScope) || 545 inSuspendBlock())) { 546 OldConditional = OutermostConditional; 547 OutermostConditional = nullptr; 548 549 OldIP = Builder.saveIP(); 550 llvm::BasicBlock *Block = OldConditional->getStartingBlock(); 551 Builder.restoreIP(CGBuilderTy::InsertPoint( 552 Block, llvm::BasicBlock::iterator(Block->back()))); 553 } 554 555 if (auto *Size = EmitLifetimeStart( 556 CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()), 557 Alloca.getPointer())) { 558 pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Alloca, 559 Size); 560 } 561 562 if (OldConditional) { 563 OutermostConditional = OldConditional; 564 Builder.restoreIP(OldIP); 565 } 566 break; 567 } 568 569 default: 570 break; 571 } 572 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true); 573 } 574 pushTemporaryCleanup(*this, M, E, Object); 575 576 // Perform derived-to-base casts and/or field accesses, to get from the 577 // temporary object we created (and, potentially, for which we extended 578 // the lifetime) to the subobject we're binding the reference to. 579 for (SubobjectAdjustment &Adjustment : llvm::reverse(Adjustments)) { 580 switch (Adjustment.Kind) { 581 case SubobjectAdjustment::DerivedToBaseAdjustment: 582 Object = 583 GetAddressOfBaseClass(Object, Adjustment.DerivedToBase.DerivedClass, 584 Adjustment.DerivedToBase.BasePath->path_begin(), 585 Adjustment.DerivedToBase.BasePath->path_end(), 586 /*NullCheckValue=*/ false, E->getExprLoc()); 587 break; 588 589 case SubobjectAdjustment::FieldAdjustment: { 590 LValue LV = MakeAddrLValue(Object, E->getType(), AlignmentSource::Decl); 591 LV = EmitLValueForField(LV, Adjustment.Field); 592 assert(LV.isSimple() && 593 "materialized temporary field is not a simple lvalue"); 594 Object = LV.getAddress(*this); 595 break; 596 } 597 598 case SubobjectAdjustment::MemberPointerAdjustment: { 599 llvm::Value *Ptr = EmitScalarExpr(Adjustment.Ptr.RHS); 600 Object = EmitCXXMemberDataPointerAddress(E, Object, Ptr, 601 Adjustment.Ptr.MPT); 602 break; 603 } 604 } 605 } 606 607 return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl); 608 } 609 610 RValue 611 CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E) { 612 // Emit the expression as an lvalue. 613 LValue LV = EmitLValue(E); 614 assert(LV.isSimple()); 615 llvm::Value *Value = LV.getPointer(*this); 616 617 if (sanitizePerformTypeCheck() && !E->getType()->isFunctionType()) { 618 // C++11 [dcl.ref]p5 (as amended by core issue 453): 619 // If a glvalue to which a reference is directly bound designates neither 620 // an existing object or function of an appropriate type nor a region of 621 // storage of suitable size and alignment to contain an object of the 622 // reference's type, the behavior is undefined. 623 QualType Ty = E->getType(); 624 EmitTypeCheck(TCK_ReferenceBinding, E->getExprLoc(), Value, Ty); 625 } 626 627 return RValue::get(Value); 628 } 629 630 631 /// getAccessedFieldNo - Given an encoded value and a result number, return the 632 /// input field number being accessed. 633 unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx, 634 const llvm::Constant *Elts) { 635 return cast<llvm::ConstantInt>(Elts->getAggregateElement(Idx)) 636 ->getZExtValue(); 637 } 638 639 /// Emit the hash_16_bytes function from include/llvm/ADT/Hashing.h. 640 static llvm::Value *emitHash16Bytes(CGBuilderTy &Builder, llvm::Value *Low, 641 llvm::Value *High) { 642 llvm::Value *KMul = Builder.getInt64(0x9ddfea08eb382d69ULL); 643 llvm::Value *K47 = Builder.getInt64(47); 644 llvm::Value *A0 = Builder.CreateMul(Builder.CreateXor(Low, High), KMul); 645 llvm::Value *A1 = Builder.CreateXor(Builder.CreateLShr(A0, K47), A0); 646 llvm::Value *B0 = Builder.CreateMul(Builder.CreateXor(High, A1), KMul); 647 llvm::Value *B1 = Builder.CreateXor(Builder.CreateLShr(B0, K47), B0); 648 return Builder.CreateMul(B1, KMul); 649 } 650 651 bool CodeGenFunction::isNullPointerAllowed(TypeCheckKind TCK) { 652 return TCK == TCK_DowncastPointer || TCK == TCK_Upcast || 653 TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation; 654 } 655 656 bool CodeGenFunction::isVptrCheckRequired(TypeCheckKind TCK, QualType Ty) { 657 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl(); 658 return (RD && RD->hasDefinition() && RD->isDynamicClass()) && 659 (TCK == TCK_MemberAccess || TCK == TCK_MemberCall || 660 TCK == TCK_DowncastPointer || TCK == TCK_DowncastReference || 661 TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation); 662 } 663 664 bool CodeGenFunction::sanitizePerformTypeCheck() const { 665 return SanOpts.has(SanitizerKind::Null) || 666 SanOpts.has(SanitizerKind::Alignment) || 667 SanOpts.has(SanitizerKind::ObjectSize) || 668 SanOpts.has(SanitizerKind::Vptr); 669 } 670 671 void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc, 672 llvm::Value *Ptr, QualType Ty, 673 CharUnits Alignment, 674 SanitizerSet SkippedChecks, 675 llvm::Value *ArraySize) { 676 if (!sanitizePerformTypeCheck()) 677 return; 678 679 // Don't check pointers outside the default address space. The null check 680 // isn't correct, the object-size check isn't supported by LLVM, and we can't 681 // communicate the addresses to the runtime handler for the vptr check. 682 if (Ptr->getType()->getPointerAddressSpace()) 683 return; 684 685 // Don't check pointers to volatile data. The behavior here is implementation- 686 // defined. 687 if (Ty.isVolatileQualified()) 688 return; 689 690 SanitizerScope SanScope(this); 691 692 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 3> Checks; 693 llvm::BasicBlock *Done = nullptr; 694 695 // Quickly determine whether we have a pointer to an alloca. It's possible 696 // to skip null checks, and some alignment checks, for these pointers. This 697 // can reduce compile-time significantly. 698 auto PtrToAlloca = dyn_cast<llvm::AllocaInst>(Ptr->stripPointerCasts()); 699 700 llvm::Value *True = llvm::ConstantInt::getTrue(getLLVMContext()); 701 llvm::Value *IsNonNull = nullptr; 702 bool IsGuaranteedNonNull = 703 SkippedChecks.has(SanitizerKind::Null) || PtrToAlloca; 704 bool AllowNullPointers = isNullPointerAllowed(TCK); 705 if ((SanOpts.has(SanitizerKind::Null) || AllowNullPointers) && 706 !IsGuaranteedNonNull) { 707 // The glvalue must not be an empty glvalue. 708 IsNonNull = Builder.CreateIsNotNull(Ptr); 709 710 // The IR builder can constant-fold the null check if the pointer points to 711 // a constant. 712 IsGuaranteedNonNull = IsNonNull == True; 713 714 // Skip the null check if the pointer is known to be non-null. 715 if (!IsGuaranteedNonNull) { 716 if (AllowNullPointers) { 717 // When performing pointer casts, it's OK if the value is null. 718 // Skip the remaining checks in that case. 719 Done = createBasicBlock("null"); 720 llvm::BasicBlock *Rest = createBasicBlock("not.null"); 721 Builder.CreateCondBr(IsNonNull, Rest, Done); 722 EmitBlock(Rest); 723 } else { 724 Checks.push_back(std::make_pair(IsNonNull, SanitizerKind::Null)); 725 } 726 } 727 } 728 729 if (SanOpts.has(SanitizerKind::ObjectSize) && 730 !SkippedChecks.has(SanitizerKind::ObjectSize) && 731 !Ty->isIncompleteType()) { 732 uint64_t TySize = CGM.getMinimumObjectSize(Ty).getQuantity(); 733 llvm::Value *Size = llvm::ConstantInt::get(IntPtrTy, TySize); 734 if (ArraySize) 735 Size = Builder.CreateMul(Size, ArraySize); 736 737 // Degenerate case: new X[0] does not need an objectsize check. 738 llvm::Constant *ConstantSize = dyn_cast<llvm::Constant>(Size); 739 if (!ConstantSize || !ConstantSize->isNullValue()) { 740 // The glvalue must refer to a large enough storage region. 741 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation 742 // to check this. 743 // FIXME: Get object address space 744 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy }; 745 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys); 746 llvm::Value *Min = Builder.getFalse(); 747 llvm::Value *NullIsUnknown = Builder.getFalse(); 748 llvm::Value *Dynamic = Builder.getFalse(); 749 llvm::Value *CastAddr = Builder.CreateBitCast(Ptr, Int8PtrTy); 750 llvm::Value *LargeEnough = Builder.CreateICmpUGE( 751 Builder.CreateCall(F, {CastAddr, Min, NullIsUnknown, Dynamic}), Size); 752 Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize)); 753 } 754 } 755 756 llvm::MaybeAlign AlignVal; 757 llvm::Value *PtrAsInt = nullptr; 758 759 if (SanOpts.has(SanitizerKind::Alignment) && 760 !SkippedChecks.has(SanitizerKind::Alignment)) { 761 AlignVal = Alignment.getAsMaybeAlign(); 762 if (!Ty->isIncompleteType() && !AlignVal) 763 AlignVal = CGM.getNaturalTypeAlignment(Ty, nullptr, nullptr, 764 /*ForPointeeType=*/true) 765 .getAsMaybeAlign(); 766 767 // The glvalue must be suitably aligned. 768 if (AlignVal && *AlignVal > llvm::Align(1) && 769 (!PtrToAlloca || PtrToAlloca->getAlign() < *AlignVal)) { 770 PtrAsInt = Builder.CreatePtrToInt(Ptr, IntPtrTy); 771 llvm::Value *Align = Builder.CreateAnd( 772 PtrAsInt, llvm::ConstantInt::get(IntPtrTy, AlignVal->value() - 1)); 773 llvm::Value *Aligned = 774 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0)); 775 if (Aligned != True) 776 Checks.push_back(std::make_pair(Aligned, SanitizerKind::Alignment)); 777 } 778 } 779 780 if (Checks.size() > 0) { 781 llvm::Constant *StaticData[] = { 782 EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(Ty), 783 llvm::ConstantInt::get(Int8Ty, AlignVal ? llvm::Log2(*AlignVal) : 1), 784 llvm::ConstantInt::get(Int8Ty, TCK)}; 785 EmitCheck(Checks, SanitizerHandler::TypeMismatch, StaticData, 786 PtrAsInt ? PtrAsInt : Ptr); 787 } 788 789 // If possible, check that the vptr indicates that there is a subobject of 790 // type Ty at offset zero within this object. 791 // 792 // C++11 [basic.life]p5,6: 793 // [For storage which does not refer to an object within its lifetime] 794 // The program has undefined behavior if: 795 // -- the [pointer or glvalue] is used to access a non-static data member 796 // or call a non-static member function 797 if (SanOpts.has(SanitizerKind::Vptr) && 798 !SkippedChecks.has(SanitizerKind::Vptr) && isVptrCheckRequired(TCK, Ty)) { 799 // Ensure that the pointer is non-null before loading it. If there is no 800 // compile-time guarantee, reuse the run-time null check or emit a new one. 801 if (!IsGuaranteedNonNull) { 802 if (!IsNonNull) 803 IsNonNull = Builder.CreateIsNotNull(Ptr); 804 if (!Done) 805 Done = createBasicBlock("vptr.null"); 806 llvm::BasicBlock *VptrNotNull = createBasicBlock("vptr.not.null"); 807 Builder.CreateCondBr(IsNonNull, VptrNotNull, Done); 808 EmitBlock(VptrNotNull); 809 } 810 811 // Compute a hash of the mangled name of the type. 812 // 813 // FIXME: This is not guaranteed to be deterministic! Move to a 814 // fingerprinting mechanism once LLVM provides one. For the time 815 // being the implementation happens to be deterministic. 816 SmallString<64> MangledName; 817 llvm::raw_svector_ostream Out(MangledName); 818 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(), 819 Out); 820 821 // Contained in NoSanitizeList based on the mangled type. 822 if (!CGM.getContext().getNoSanitizeList().containsType(SanitizerKind::Vptr, 823 Out.str())) { 824 llvm::hash_code TypeHash = hash_value(Out.str()); 825 826 // Load the vptr, and compute hash_16_bytes(TypeHash, vptr). 827 llvm::Value *Low = llvm::ConstantInt::get(Int64Ty, TypeHash); 828 llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0); 829 Address VPtrAddr(Builder.CreateBitCast(Ptr, VPtrTy), IntPtrTy, 830 getPointerAlign()); 831 llvm::Value *VPtrVal = Builder.CreateLoad(VPtrAddr); 832 llvm::Value *High = Builder.CreateZExt(VPtrVal, Int64Ty); 833 834 llvm::Value *Hash = emitHash16Bytes(Builder, Low, High); 835 Hash = Builder.CreateTrunc(Hash, IntPtrTy); 836 837 // Look the hash up in our cache. 838 const int CacheSize = 128; 839 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize); 840 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable, 841 "__ubsan_vptr_type_cache"); 842 llvm::Value *Slot = Builder.CreateAnd(Hash, 843 llvm::ConstantInt::get(IntPtrTy, 844 CacheSize-1)); 845 llvm::Value *Indices[] = { Builder.getInt32(0), Slot }; 846 llvm::Value *CacheVal = Builder.CreateAlignedLoad( 847 IntPtrTy, Builder.CreateInBoundsGEP(HashTable, Cache, Indices), 848 getPointerAlign()); 849 850 // If the hash isn't in the cache, call a runtime handler to perform the 851 // hard work of checking whether the vptr is for an object of the right 852 // type. This will either fill in the cache and return, or produce a 853 // diagnostic. 854 llvm::Value *EqualHash = Builder.CreateICmpEQ(CacheVal, Hash); 855 llvm::Constant *StaticData[] = { 856 EmitCheckSourceLocation(Loc), 857 EmitCheckTypeDescriptor(Ty), 858 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()), 859 llvm::ConstantInt::get(Int8Ty, TCK) 860 }; 861 llvm::Value *DynamicData[] = { Ptr, Hash }; 862 EmitCheck(std::make_pair(EqualHash, SanitizerKind::Vptr), 863 SanitizerHandler::DynamicTypeCacheMiss, StaticData, 864 DynamicData); 865 } 866 } 867 868 if (Done) { 869 Builder.CreateBr(Done); 870 EmitBlock(Done); 871 } 872 } 873 874 llvm::Value *CodeGenFunction::LoadPassedObjectSize(const Expr *E, 875 QualType EltTy) { 876 ASTContext &C = getContext(); 877 uint64_t EltSize = C.getTypeSizeInChars(EltTy).getQuantity(); 878 if (!EltSize) 879 return nullptr; 880 881 auto *ArrayDeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts()); 882 if (!ArrayDeclRef) 883 return nullptr; 884 885 auto *ParamDecl = dyn_cast<ParmVarDecl>(ArrayDeclRef->getDecl()); 886 if (!ParamDecl) 887 return nullptr; 888 889 auto *POSAttr = ParamDecl->getAttr<PassObjectSizeAttr>(); 890 if (!POSAttr) 891 return nullptr; 892 893 // Don't load the size if it's a lower bound. 894 int POSType = POSAttr->getType(); 895 if (POSType != 0 && POSType != 1) 896 return nullptr; 897 898 // Find the implicit size parameter. 899 auto PassedSizeIt = SizeArguments.find(ParamDecl); 900 if (PassedSizeIt == SizeArguments.end()) 901 return nullptr; 902 903 const ImplicitParamDecl *PassedSizeDecl = PassedSizeIt->second; 904 assert(LocalDeclMap.count(PassedSizeDecl) && "Passed size not loadable"); 905 Address AddrOfSize = LocalDeclMap.find(PassedSizeDecl)->second; 906 llvm::Value *SizeInBytes = EmitLoadOfScalar(AddrOfSize, /*Volatile=*/false, 907 C.getSizeType(), E->getExprLoc()); 908 llvm::Value *SizeOfElement = 909 llvm::ConstantInt::get(SizeInBytes->getType(), EltSize); 910 return Builder.CreateUDiv(SizeInBytes, SizeOfElement); 911 } 912 913 /// If Base is known to point to the start of an array, return the length of 914 /// that array. Return 0 if the length cannot be determined. 915 static llvm::Value *getArrayIndexingBound(CodeGenFunction &CGF, 916 const Expr *Base, 917 QualType &IndexedType, 918 LangOptions::StrictFlexArraysLevelKind 919 StrictFlexArraysLevel) { 920 // For the vector indexing extension, the bound is the number of elements. 921 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) { 922 IndexedType = Base->getType(); 923 return CGF.Builder.getInt32(VT->getNumElements()); 924 } 925 926 Base = Base->IgnoreParens(); 927 928 if (const auto *CE = dyn_cast<CastExpr>(Base)) { 929 if (CE->getCastKind() == CK_ArrayToPointerDecay && 930 !CE->getSubExpr()->isFlexibleArrayMemberLike(CGF.getContext(), 931 StrictFlexArraysLevel)) { 932 IndexedType = CE->getSubExpr()->getType(); 933 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe(); 934 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT)) 935 return CGF.Builder.getInt(CAT->getSize()); 936 else if (const auto *VAT = dyn_cast<VariableArrayType>(AT)) 937 return CGF.getVLASize(VAT).NumElts; 938 // Ignore pass_object_size here. It's not applicable on decayed pointers. 939 } 940 } 941 942 QualType EltTy{Base->getType()->getPointeeOrArrayElementType(), 0}; 943 if (llvm::Value *POS = CGF.LoadPassedObjectSize(Base, EltTy)) { 944 IndexedType = Base->getType(); 945 return POS; 946 } 947 948 return nullptr; 949 } 950 951 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base, 952 llvm::Value *Index, QualType IndexType, 953 bool Accessed) { 954 assert(SanOpts.has(SanitizerKind::ArrayBounds) && 955 "should not be called unless adding bounds checks"); 956 SanitizerScope SanScope(this); 957 958 const LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel = 959 getLangOpts().getStrictFlexArraysLevel(); 960 961 QualType IndexedType; 962 llvm::Value *Bound = 963 getArrayIndexingBound(*this, Base, IndexedType, StrictFlexArraysLevel); 964 if (!Bound) 965 return; 966 967 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType(); 968 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned); 969 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false); 970 971 llvm::Constant *StaticData[] = { 972 EmitCheckSourceLocation(E->getExprLoc()), 973 EmitCheckTypeDescriptor(IndexedType), 974 EmitCheckTypeDescriptor(IndexType) 975 }; 976 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal) 977 : Builder.CreateICmpULE(IndexVal, BoundVal); 978 EmitCheck(std::make_pair(Check, SanitizerKind::ArrayBounds), 979 SanitizerHandler::OutOfBounds, StaticData, Index); 980 } 981 982 983 CodeGenFunction::ComplexPairTy CodeGenFunction:: 984 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV, 985 bool isInc, bool isPre) { 986 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc()); 987 988 llvm::Value *NextVal; 989 if (isa<llvm::IntegerType>(InVal.first->getType())) { 990 uint64_t AmountVal = isInc ? 1 : -1; 991 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true); 992 993 // Add the inc/dec to the real part. 994 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec"); 995 } else { 996 QualType ElemTy = E->getType()->castAs<ComplexType>()->getElementType(); 997 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1); 998 if (!isInc) 999 FVal.changeSign(); 1000 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal); 1001 1002 // Add the inc/dec to the real part. 1003 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec"); 1004 } 1005 1006 ComplexPairTy IncVal(NextVal, InVal.second); 1007 1008 // Store the updated result through the lvalue. 1009 EmitStoreOfComplex(IncVal, LV, /*init*/ false); 1010 if (getLangOpts().OpenMP) 1011 CGM.getOpenMPRuntime().checkAndEmitLastprivateConditional(*this, 1012 E->getSubExpr()); 1013 1014 // If this is a postinc, return the value read from memory, otherwise use the 1015 // updated value. 1016 return isPre ? IncVal : InVal; 1017 } 1018 1019 void CodeGenModule::EmitExplicitCastExprType(const ExplicitCastExpr *E, 1020 CodeGenFunction *CGF) { 1021 // Bind VLAs in the cast type. 1022 if (CGF && E->getType()->isVariablyModifiedType()) 1023 CGF->EmitVariablyModifiedType(E->getType()); 1024 1025 if (CGDebugInfo *DI = getModuleDebugInfo()) 1026 DI->EmitExplicitCastType(E->getType()); 1027 } 1028 1029 //===----------------------------------------------------------------------===// 1030 // LValue Expression Emission 1031 //===----------------------------------------------------------------------===// 1032 1033 static Address EmitPointerWithAlignment(const Expr *E, LValueBaseInfo *BaseInfo, 1034 TBAAAccessInfo *TBAAInfo, 1035 KnownNonNull_t IsKnownNonNull, 1036 CodeGenFunction &CGF) { 1037 // We allow this with ObjC object pointers because of fragile ABIs. 1038 assert(E->getType()->isPointerType() || 1039 E->getType()->isObjCObjectPointerType()); 1040 E = E->IgnoreParens(); 1041 1042 // Casts: 1043 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) { 1044 if (const auto *ECE = dyn_cast<ExplicitCastExpr>(CE)) 1045 CGF.CGM.EmitExplicitCastExprType(ECE, &CGF); 1046 1047 switch (CE->getCastKind()) { 1048 // Non-converting casts (but not C's implicit conversion from void*). 1049 case CK_BitCast: 1050 case CK_NoOp: 1051 case CK_AddressSpaceConversion: 1052 if (auto PtrTy = CE->getSubExpr()->getType()->getAs<PointerType>()) { 1053 if (PtrTy->getPointeeType()->isVoidType()) 1054 break; 1055 1056 LValueBaseInfo InnerBaseInfo; 1057 TBAAAccessInfo InnerTBAAInfo; 1058 Address Addr = CGF.EmitPointerWithAlignment( 1059 CE->getSubExpr(), &InnerBaseInfo, &InnerTBAAInfo, IsKnownNonNull); 1060 if (BaseInfo) *BaseInfo = InnerBaseInfo; 1061 if (TBAAInfo) *TBAAInfo = InnerTBAAInfo; 1062 1063 if (isa<ExplicitCastExpr>(CE)) { 1064 LValueBaseInfo TargetTypeBaseInfo; 1065 TBAAAccessInfo TargetTypeTBAAInfo; 1066 CharUnits Align = CGF.CGM.getNaturalPointeeTypeAlignment( 1067 E->getType(), &TargetTypeBaseInfo, &TargetTypeTBAAInfo); 1068 if (TBAAInfo) 1069 *TBAAInfo = 1070 CGF.CGM.mergeTBAAInfoForCast(*TBAAInfo, TargetTypeTBAAInfo); 1071 // If the source l-value is opaque, honor the alignment of the 1072 // casted-to type. 1073 if (InnerBaseInfo.getAlignmentSource() != AlignmentSource::Decl) { 1074 if (BaseInfo) 1075 BaseInfo->mergeForCast(TargetTypeBaseInfo); 1076 Addr = Address(Addr.getPointer(), Addr.getElementType(), Align, 1077 IsKnownNonNull); 1078 } 1079 } 1080 1081 if (CGF.SanOpts.has(SanitizerKind::CFIUnrelatedCast) && 1082 CE->getCastKind() == CK_BitCast) { 1083 if (auto PT = E->getType()->getAs<PointerType>()) 1084 CGF.EmitVTablePtrCheckForCast(PT->getPointeeType(), Addr, 1085 /*MayBeNull=*/true, 1086 CodeGenFunction::CFITCK_UnrelatedCast, 1087 CE->getBeginLoc()); 1088 } 1089 1090 llvm::Type *ElemTy = 1091 CGF.ConvertTypeForMem(E->getType()->getPointeeType()); 1092 Addr = Addr.withElementType(ElemTy); 1093 if (CE->getCastKind() == CK_AddressSpaceConversion) 1094 Addr = CGF.Builder.CreateAddrSpaceCast(Addr, 1095 CGF.ConvertType(E->getType())); 1096 return Addr; 1097 } 1098 break; 1099 1100 // Array-to-pointer decay. 1101 case CK_ArrayToPointerDecay: 1102 return CGF.EmitArrayToPointerDecay(CE->getSubExpr(), BaseInfo, TBAAInfo); 1103 1104 // Derived-to-base conversions. 1105 case CK_UncheckedDerivedToBase: 1106 case CK_DerivedToBase: { 1107 // TODO: Support accesses to members of base classes in TBAA. For now, we 1108 // conservatively pretend that the complete object is of the base class 1109 // type. 1110 if (TBAAInfo) 1111 *TBAAInfo = CGF.CGM.getTBAAAccessInfo(E->getType()); 1112 Address Addr = CGF.EmitPointerWithAlignment( 1113 CE->getSubExpr(), BaseInfo, nullptr, 1114 (KnownNonNull_t)(IsKnownNonNull || 1115 CE->getCastKind() == CK_UncheckedDerivedToBase)); 1116 auto Derived = CE->getSubExpr()->getType()->getPointeeCXXRecordDecl(); 1117 return CGF.GetAddressOfBaseClass( 1118 Addr, Derived, CE->path_begin(), CE->path_end(), 1119 CGF.ShouldNullCheckClassCastValue(CE), CE->getExprLoc()); 1120 } 1121 1122 // TODO: Is there any reason to treat base-to-derived conversions 1123 // specially? 1124 default: 1125 break; 1126 } 1127 } 1128 1129 // Unary &. 1130 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) { 1131 if (UO->getOpcode() == UO_AddrOf) { 1132 LValue LV = CGF.EmitLValue(UO->getSubExpr(), IsKnownNonNull); 1133 if (BaseInfo) *BaseInfo = LV.getBaseInfo(); 1134 if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo(); 1135 return LV.getAddress(CGF); 1136 } 1137 } 1138 1139 // std::addressof and variants. 1140 if (auto *Call = dyn_cast<CallExpr>(E)) { 1141 switch (Call->getBuiltinCallee()) { 1142 default: 1143 break; 1144 case Builtin::BIaddressof: 1145 case Builtin::BI__addressof: 1146 case Builtin::BI__builtin_addressof: { 1147 LValue LV = CGF.EmitLValue(Call->getArg(0), IsKnownNonNull); 1148 if (BaseInfo) *BaseInfo = LV.getBaseInfo(); 1149 if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo(); 1150 return LV.getAddress(CGF); 1151 } 1152 } 1153 } 1154 1155 // TODO: conditional operators, comma. 1156 1157 // Otherwise, use the alignment of the type. 1158 CharUnits Align = 1159 CGF.CGM.getNaturalPointeeTypeAlignment(E->getType(), BaseInfo, TBAAInfo); 1160 llvm::Type *ElemTy = CGF.ConvertTypeForMem(E->getType()->getPointeeType()); 1161 return Address(CGF.EmitScalarExpr(E), ElemTy, Align, IsKnownNonNull); 1162 } 1163 1164 /// EmitPointerWithAlignment - Given an expression of pointer type, try to 1165 /// derive a more accurate bound on the alignment of the pointer. 1166 Address CodeGenFunction::EmitPointerWithAlignment( 1167 const Expr *E, LValueBaseInfo *BaseInfo, TBAAAccessInfo *TBAAInfo, 1168 KnownNonNull_t IsKnownNonNull) { 1169 Address Addr = 1170 ::EmitPointerWithAlignment(E, BaseInfo, TBAAInfo, IsKnownNonNull, *this); 1171 if (IsKnownNonNull && !Addr.isKnownNonNull()) 1172 Addr.setKnownNonNull(); 1173 return Addr; 1174 } 1175 1176 llvm::Value *CodeGenFunction::EmitNonNullRValueCheck(RValue RV, QualType T) { 1177 llvm::Value *V = RV.getScalarVal(); 1178 if (auto MPT = T->getAs<MemberPointerType>()) 1179 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, V, MPT); 1180 return Builder.CreateICmpNE(V, llvm::Constant::getNullValue(V->getType())); 1181 } 1182 1183 RValue CodeGenFunction::GetUndefRValue(QualType Ty) { 1184 if (Ty->isVoidType()) 1185 return RValue::get(nullptr); 1186 1187 switch (getEvaluationKind(Ty)) { 1188 case TEK_Complex: { 1189 llvm::Type *EltTy = 1190 ConvertType(Ty->castAs<ComplexType>()->getElementType()); 1191 llvm::Value *U = llvm::UndefValue::get(EltTy); 1192 return RValue::getComplex(std::make_pair(U, U)); 1193 } 1194 1195 // If this is a use of an undefined aggregate type, the aggregate must have an 1196 // identifiable address. Just because the contents of the value are undefined 1197 // doesn't mean that the address can't be taken and compared. 1198 case TEK_Aggregate: { 1199 Address DestPtr = CreateMemTemp(Ty, "undef.agg.tmp"); 1200 return RValue::getAggregate(DestPtr); 1201 } 1202 1203 case TEK_Scalar: 1204 return RValue::get(llvm::UndefValue::get(ConvertType(Ty))); 1205 } 1206 llvm_unreachable("bad evaluation kind"); 1207 } 1208 1209 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E, 1210 const char *Name) { 1211 ErrorUnsupported(E, Name); 1212 return GetUndefRValue(E->getType()); 1213 } 1214 1215 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E, 1216 const char *Name) { 1217 ErrorUnsupported(E, Name); 1218 llvm::Type *ElTy = ConvertType(E->getType()); 1219 llvm::Type *Ty = llvm::PointerType::getUnqual(ElTy); 1220 return MakeAddrLValue( 1221 Address(llvm::UndefValue::get(Ty), ElTy, CharUnits::One()), E->getType()); 1222 } 1223 1224 bool CodeGenFunction::IsWrappedCXXThis(const Expr *Obj) { 1225 const Expr *Base = Obj; 1226 while (!isa<CXXThisExpr>(Base)) { 1227 // The result of a dynamic_cast can be null. 1228 if (isa<CXXDynamicCastExpr>(Base)) 1229 return false; 1230 1231 if (const auto *CE = dyn_cast<CastExpr>(Base)) { 1232 Base = CE->getSubExpr(); 1233 } else if (const auto *PE = dyn_cast<ParenExpr>(Base)) { 1234 Base = PE->getSubExpr(); 1235 } else if (const auto *UO = dyn_cast<UnaryOperator>(Base)) { 1236 if (UO->getOpcode() == UO_Extension) 1237 Base = UO->getSubExpr(); 1238 else 1239 return false; 1240 } else { 1241 return false; 1242 } 1243 } 1244 return true; 1245 } 1246 1247 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) { 1248 LValue LV; 1249 if (SanOpts.has(SanitizerKind::ArrayBounds) && isa<ArraySubscriptExpr>(E)) 1250 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true); 1251 else 1252 LV = EmitLValue(E); 1253 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) { 1254 SanitizerSet SkippedChecks; 1255 if (const auto *ME = dyn_cast<MemberExpr>(E)) { 1256 bool IsBaseCXXThis = IsWrappedCXXThis(ME->getBase()); 1257 if (IsBaseCXXThis) 1258 SkippedChecks.set(SanitizerKind::Alignment, true); 1259 if (IsBaseCXXThis || isa<DeclRefExpr>(ME->getBase())) 1260 SkippedChecks.set(SanitizerKind::Null, true); 1261 } 1262 EmitTypeCheck(TCK, E->getExprLoc(), LV.getPointer(*this), E->getType(), 1263 LV.getAlignment(), SkippedChecks); 1264 } 1265 return LV; 1266 } 1267 1268 /// EmitLValue - Emit code to compute a designator that specifies the location 1269 /// of the expression. 1270 /// 1271 /// This can return one of two things: a simple address or a bitfield reference. 1272 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be 1273 /// an LLVM pointer type. 1274 /// 1275 /// If this returns a bitfield reference, nothing about the pointee type of the 1276 /// LLVM value is known: For example, it may not be a pointer to an integer. 1277 /// 1278 /// If this returns a normal address, and if the lvalue's C type is fixed size, 1279 /// this method guarantees that the returned pointer type will point to an LLVM 1280 /// type of the same size of the lvalue's type. If the lvalue has a variable 1281 /// length type, this is not possible. 1282 /// 1283 LValue CodeGenFunction::EmitLValue(const Expr *E, 1284 KnownNonNull_t IsKnownNonNull) { 1285 LValue LV = EmitLValueHelper(E, IsKnownNonNull); 1286 if (IsKnownNonNull && !LV.isKnownNonNull()) 1287 LV.setKnownNonNull(); 1288 return LV; 1289 } 1290 1291 LValue CodeGenFunction::EmitLValueHelper(const Expr *E, 1292 KnownNonNull_t IsKnownNonNull) { 1293 ApplyDebugLocation DL(*this, E); 1294 switch (E->getStmtClass()) { 1295 default: return EmitUnsupportedLValue(E, "l-value expression"); 1296 1297 case Expr::ObjCPropertyRefExprClass: 1298 llvm_unreachable("cannot emit a property reference directly"); 1299 1300 case Expr::ObjCSelectorExprClass: 1301 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E)); 1302 case Expr::ObjCIsaExprClass: 1303 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E)); 1304 case Expr::BinaryOperatorClass: 1305 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E)); 1306 case Expr::CompoundAssignOperatorClass: { 1307 QualType Ty = E->getType(); 1308 if (const AtomicType *AT = Ty->getAs<AtomicType>()) 1309 Ty = AT->getValueType(); 1310 if (!Ty->isAnyComplexType()) 1311 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E)); 1312 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E)); 1313 } 1314 case Expr::CallExprClass: 1315 case Expr::CXXMemberCallExprClass: 1316 case Expr::CXXOperatorCallExprClass: 1317 case Expr::UserDefinedLiteralClass: 1318 return EmitCallExprLValue(cast<CallExpr>(E)); 1319 case Expr::CXXRewrittenBinaryOperatorClass: 1320 return EmitLValue(cast<CXXRewrittenBinaryOperator>(E)->getSemanticForm(), 1321 IsKnownNonNull); 1322 case Expr::VAArgExprClass: 1323 return EmitVAArgExprLValue(cast<VAArgExpr>(E)); 1324 case Expr::DeclRefExprClass: 1325 return EmitDeclRefLValue(cast<DeclRefExpr>(E)); 1326 case Expr::ConstantExprClass: { 1327 const ConstantExpr *CE = cast<ConstantExpr>(E); 1328 if (llvm::Value *Result = ConstantEmitter(*this).tryEmitConstantExpr(CE)) { 1329 QualType RetType = cast<CallExpr>(CE->getSubExpr()->IgnoreImplicit()) 1330 ->getCallReturnType(getContext()) 1331 ->getPointeeType(); 1332 return MakeNaturalAlignAddrLValue(Result, RetType); 1333 } 1334 return EmitLValue(cast<ConstantExpr>(E)->getSubExpr(), IsKnownNonNull); 1335 } 1336 case Expr::ParenExprClass: 1337 return EmitLValue(cast<ParenExpr>(E)->getSubExpr(), IsKnownNonNull); 1338 case Expr::GenericSelectionExprClass: 1339 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr(), 1340 IsKnownNonNull); 1341 case Expr::PredefinedExprClass: 1342 return EmitPredefinedLValue(cast<PredefinedExpr>(E)); 1343 case Expr::StringLiteralClass: 1344 return EmitStringLiteralLValue(cast<StringLiteral>(E)); 1345 case Expr::ObjCEncodeExprClass: 1346 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E)); 1347 case Expr::PseudoObjectExprClass: 1348 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E)); 1349 case Expr::InitListExprClass: 1350 return EmitInitListLValue(cast<InitListExpr>(E)); 1351 case Expr::CXXTemporaryObjectExprClass: 1352 case Expr::CXXConstructExprClass: 1353 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E)); 1354 case Expr::CXXBindTemporaryExprClass: 1355 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E)); 1356 case Expr::CXXUuidofExprClass: 1357 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E)); 1358 case Expr::LambdaExprClass: 1359 return EmitAggExprToLValue(E); 1360 1361 case Expr::ExprWithCleanupsClass: { 1362 const auto *cleanups = cast<ExprWithCleanups>(E); 1363 RunCleanupsScope Scope(*this); 1364 LValue LV = EmitLValue(cleanups->getSubExpr(), IsKnownNonNull); 1365 if (LV.isSimple()) { 1366 // Defend against branches out of gnu statement expressions surrounded by 1367 // cleanups. 1368 Address Addr = LV.getAddress(*this); 1369 llvm::Value *V = Addr.getPointer(); 1370 Scope.ForceCleanup({&V}); 1371 return LValue::MakeAddr(Addr.withPointer(V, Addr.isKnownNonNull()), 1372 LV.getType(), getContext(), LV.getBaseInfo(), 1373 LV.getTBAAInfo()); 1374 } 1375 // FIXME: Is it possible to create an ExprWithCleanups that produces a 1376 // bitfield lvalue or some other non-simple lvalue? 1377 return LV; 1378 } 1379 1380 case Expr::CXXDefaultArgExprClass: { 1381 auto *DAE = cast<CXXDefaultArgExpr>(E); 1382 CXXDefaultArgExprScope Scope(*this, DAE); 1383 return EmitLValue(DAE->getExpr(), IsKnownNonNull); 1384 } 1385 case Expr::CXXDefaultInitExprClass: { 1386 auto *DIE = cast<CXXDefaultInitExpr>(E); 1387 CXXDefaultInitExprScope Scope(*this, DIE); 1388 return EmitLValue(DIE->getExpr(), IsKnownNonNull); 1389 } 1390 case Expr::CXXTypeidExprClass: 1391 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E)); 1392 1393 case Expr::ObjCMessageExprClass: 1394 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E)); 1395 case Expr::ObjCIvarRefExprClass: 1396 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E)); 1397 case Expr::StmtExprClass: 1398 return EmitStmtExprLValue(cast<StmtExpr>(E)); 1399 case Expr::UnaryOperatorClass: 1400 return EmitUnaryOpLValue(cast<UnaryOperator>(E)); 1401 case Expr::ArraySubscriptExprClass: 1402 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E)); 1403 case Expr::MatrixSubscriptExprClass: 1404 return EmitMatrixSubscriptExpr(cast<MatrixSubscriptExpr>(E)); 1405 case Expr::OMPArraySectionExprClass: 1406 return EmitOMPArraySectionExpr(cast<OMPArraySectionExpr>(E)); 1407 case Expr::ExtVectorElementExprClass: 1408 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E)); 1409 case Expr::CXXThisExprClass: 1410 return MakeAddrLValue(LoadCXXThisAddress(), E->getType()); 1411 case Expr::MemberExprClass: 1412 return EmitMemberExpr(cast<MemberExpr>(E)); 1413 case Expr::CompoundLiteralExprClass: 1414 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E)); 1415 case Expr::ConditionalOperatorClass: 1416 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E)); 1417 case Expr::BinaryConditionalOperatorClass: 1418 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E)); 1419 case Expr::ChooseExprClass: 1420 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(), IsKnownNonNull); 1421 case Expr::OpaqueValueExprClass: 1422 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E)); 1423 case Expr::SubstNonTypeTemplateParmExprClass: 1424 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement(), 1425 IsKnownNonNull); 1426 case Expr::ImplicitCastExprClass: 1427 case Expr::CStyleCastExprClass: 1428 case Expr::CXXFunctionalCastExprClass: 1429 case Expr::CXXStaticCastExprClass: 1430 case Expr::CXXDynamicCastExprClass: 1431 case Expr::CXXReinterpretCastExprClass: 1432 case Expr::CXXConstCastExprClass: 1433 case Expr::CXXAddrspaceCastExprClass: 1434 case Expr::ObjCBridgedCastExprClass: 1435 return EmitCastLValue(cast<CastExpr>(E)); 1436 1437 case Expr::MaterializeTemporaryExprClass: 1438 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E)); 1439 1440 case Expr::CoawaitExprClass: 1441 return EmitCoawaitLValue(cast<CoawaitExpr>(E)); 1442 case Expr::CoyieldExprClass: 1443 return EmitCoyieldLValue(cast<CoyieldExpr>(E)); 1444 } 1445 } 1446 1447 /// Given an object of the given canonical type, can we safely copy a 1448 /// value out of it based on its initializer? 1449 static bool isConstantEmittableObjectType(QualType type) { 1450 assert(type.isCanonical()); 1451 assert(!type->isReferenceType()); 1452 1453 // Must be const-qualified but non-volatile. 1454 Qualifiers qs = type.getLocalQualifiers(); 1455 if (!qs.hasConst() || qs.hasVolatile()) return false; 1456 1457 // Otherwise, all object types satisfy this except C++ classes with 1458 // mutable subobjects or non-trivial copy/destroy behavior. 1459 if (const auto *RT = dyn_cast<RecordType>(type)) 1460 if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) 1461 if (RD->hasMutableFields() || !RD->isTrivial()) 1462 return false; 1463 1464 return true; 1465 } 1466 1467 /// Can we constant-emit a load of a reference to a variable of the 1468 /// given type? This is different from predicates like 1469 /// Decl::mightBeUsableInConstantExpressions because we do want it to apply 1470 /// in situations that don't necessarily satisfy the language's rules 1471 /// for this (e.g. C++'s ODR-use rules). For example, we want to able 1472 /// to do this with const float variables even if those variables 1473 /// aren't marked 'constexpr'. 1474 enum ConstantEmissionKind { 1475 CEK_None, 1476 CEK_AsReferenceOnly, 1477 CEK_AsValueOrReference, 1478 CEK_AsValueOnly 1479 }; 1480 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) { 1481 type = type.getCanonicalType(); 1482 if (const auto *ref = dyn_cast<ReferenceType>(type)) { 1483 if (isConstantEmittableObjectType(ref->getPointeeType())) 1484 return CEK_AsValueOrReference; 1485 return CEK_AsReferenceOnly; 1486 } 1487 if (isConstantEmittableObjectType(type)) 1488 return CEK_AsValueOnly; 1489 return CEK_None; 1490 } 1491 1492 /// Try to emit a reference to the given value without producing it as 1493 /// an l-value. This is just an optimization, but it avoids us needing 1494 /// to emit global copies of variables if they're named without triggering 1495 /// a formal use in a context where we can't emit a direct reference to them, 1496 /// for instance if a block or lambda or a member of a local class uses a 1497 /// const int variable or constexpr variable from an enclosing function. 1498 CodeGenFunction::ConstantEmission 1499 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) { 1500 ValueDecl *value = refExpr->getDecl(); 1501 1502 // The value needs to be an enum constant or a constant variable. 1503 ConstantEmissionKind CEK; 1504 if (isa<ParmVarDecl>(value)) { 1505 CEK = CEK_None; 1506 } else if (auto *var = dyn_cast<VarDecl>(value)) { 1507 CEK = checkVarTypeForConstantEmission(var->getType()); 1508 } else if (isa<EnumConstantDecl>(value)) { 1509 CEK = CEK_AsValueOnly; 1510 } else { 1511 CEK = CEK_None; 1512 } 1513 if (CEK == CEK_None) return ConstantEmission(); 1514 1515 Expr::EvalResult result; 1516 bool resultIsReference; 1517 QualType resultType; 1518 1519 // It's best to evaluate all the way as an r-value if that's permitted. 1520 if (CEK != CEK_AsReferenceOnly && 1521 refExpr->EvaluateAsRValue(result, getContext())) { 1522 resultIsReference = false; 1523 resultType = refExpr->getType(); 1524 1525 // Otherwise, try to evaluate as an l-value. 1526 } else if (CEK != CEK_AsValueOnly && 1527 refExpr->EvaluateAsLValue(result, getContext())) { 1528 resultIsReference = true; 1529 resultType = value->getType(); 1530 1531 // Failure. 1532 } else { 1533 return ConstantEmission(); 1534 } 1535 1536 // In any case, if the initializer has side-effects, abandon ship. 1537 if (result.HasSideEffects) 1538 return ConstantEmission(); 1539 1540 // In CUDA/HIP device compilation, a lambda may capture a reference variable 1541 // referencing a global host variable by copy. In this case the lambda should 1542 // make a copy of the value of the global host variable. The DRE of the 1543 // captured reference variable cannot be emitted as load from the host 1544 // global variable as compile time constant, since the host variable is not 1545 // accessible on device. The DRE of the captured reference variable has to be 1546 // loaded from captures. 1547 if (CGM.getLangOpts().CUDAIsDevice && result.Val.isLValue() && 1548 refExpr->refersToEnclosingVariableOrCapture()) { 1549 auto *MD = dyn_cast_or_null<CXXMethodDecl>(CurCodeDecl); 1550 if (MD && MD->getParent()->isLambda() && 1551 MD->getOverloadedOperator() == OO_Call) { 1552 const APValue::LValueBase &base = result.Val.getLValueBase(); 1553 if (const ValueDecl *D = base.dyn_cast<const ValueDecl *>()) { 1554 if (const VarDecl *VD = dyn_cast<const VarDecl>(D)) { 1555 if (!VD->hasAttr<CUDADeviceAttr>()) { 1556 return ConstantEmission(); 1557 } 1558 } 1559 } 1560 } 1561 } 1562 1563 // Emit as a constant. 1564 auto C = ConstantEmitter(*this).emitAbstract(refExpr->getLocation(), 1565 result.Val, resultType); 1566 1567 // Make sure we emit a debug reference to the global variable. 1568 // This should probably fire even for 1569 if (isa<VarDecl>(value)) { 1570 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value))) 1571 EmitDeclRefExprDbgValue(refExpr, result.Val); 1572 } else { 1573 assert(isa<EnumConstantDecl>(value)); 1574 EmitDeclRefExprDbgValue(refExpr, result.Val); 1575 } 1576 1577 // If we emitted a reference constant, we need to dereference that. 1578 if (resultIsReference) 1579 return ConstantEmission::forReference(C); 1580 1581 return ConstantEmission::forValue(C); 1582 } 1583 1584 static DeclRefExpr *tryToConvertMemberExprToDeclRefExpr(CodeGenFunction &CGF, 1585 const MemberExpr *ME) { 1586 if (auto *VD = dyn_cast<VarDecl>(ME->getMemberDecl())) { 1587 // Try to emit static variable member expressions as DREs. 1588 return DeclRefExpr::Create( 1589 CGF.getContext(), NestedNameSpecifierLoc(), SourceLocation(), VD, 1590 /*RefersToEnclosingVariableOrCapture=*/false, ME->getExprLoc(), 1591 ME->getType(), ME->getValueKind(), nullptr, nullptr, ME->isNonOdrUse()); 1592 } 1593 return nullptr; 1594 } 1595 1596 CodeGenFunction::ConstantEmission 1597 CodeGenFunction::tryEmitAsConstant(const MemberExpr *ME) { 1598 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, ME)) 1599 return tryEmitAsConstant(DRE); 1600 return ConstantEmission(); 1601 } 1602 1603 llvm::Value *CodeGenFunction::emitScalarConstant( 1604 const CodeGenFunction::ConstantEmission &Constant, Expr *E) { 1605 assert(Constant && "not a constant"); 1606 if (Constant.isReference()) 1607 return EmitLoadOfLValue(Constant.getReferenceLValue(*this, E), 1608 E->getExprLoc()) 1609 .getScalarVal(); 1610 return Constant.getValue(); 1611 } 1612 1613 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue, 1614 SourceLocation Loc) { 1615 return EmitLoadOfScalar(lvalue.getAddress(*this), lvalue.isVolatile(), 1616 lvalue.getType(), Loc, lvalue.getBaseInfo(), 1617 lvalue.getTBAAInfo(), lvalue.isNontemporal()); 1618 } 1619 1620 static bool hasBooleanRepresentation(QualType Ty) { 1621 if (Ty->isBooleanType()) 1622 return true; 1623 1624 if (const EnumType *ET = Ty->getAs<EnumType>()) 1625 return ET->getDecl()->getIntegerType()->isBooleanType(); 1626 1627 if (const AtomicType *AT = Ty->getAs<AtomicType>()) 1628 return hasBooleanRepresentation(AT->getValueType()); 1629 1630 return false; 1631 } 1632 1633 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty, 1634 llvm::APInt &Min, llvm::APInt &End, 1635 bool StrictEnums, bool IsBool) { 1636 const EnumType *ET = Ty->getAs<EnumType>(); 1637 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums && 1638 ET && !ET->getDecl()->isFixed(); 1639 if (!IsBool && !IsRegularCPlusPlusEnum) 1640 return false; 1641 1642 if (IsBool) { 1643 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0); 1644 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2); 1645 } else { 1646 const EnumDecl *ED = ET->getDecl(); 1647 ED->getValueRange(End, Min); 1648 } 1649 return true; 1650 } 1651 1652 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) { 1653 llvm::APInt Min, End; 1654 if (!getRangeForType(*this, Ty, Min, End, CGM.getCodeGenOpts().StrictEnums, 1655 hasBooleanRepresentation(Ty))) 1656 return nullptr; 1657 1658 llvm::MDBuilder MDHelper(getLLVMContext()); 1659 return MDHelper.createRange(Min, End); 1660 } 1661 1662 bool CodeGenFunction::EmitScalarRangeCheck(llvm::Value *Value, QualType Ty, 1663 SourceLocation Loc) { 1664 bool HasBoolCheck = SanOpts.has(SanitizerKind::Bool); 1665 bool HasEnumCheck = SanOpts.has(SanitizerKind::Enum); 1666 if (!HasBoolCheck && !HasEnumCheck) 1667 return false; 1668 1669 bool IsBool = hasBooleanRepresentation(Ty) || 1670 NSAPI(CGM.getContext()).isObjCBOOLType(Ty); 1671 bool NeedsBoolCheck = HasBoolCheck && IsBool; 1672 bool NeedsEnumCheck = HasEnumCheck && Ty->getAs<EnumType>(); 1673 if (!NeedsBoolCheck && !NeedsEnumCheck) 1674 return false; 1675 1676 // Single-bit booleans don't need to be checked. Special-case this to avoid 1677 // a bit width mismatch when handling bitfield values. This is handled by 1678 // EmitFromMemory for the non-bitfield case. 1679 if (IsBool && 1680 cast<llvm::IntegerType>(Value->getType())->getBitWidth() == 1) 1681 return false; 1682 1683 llvm::APInt Min, End; 1684 if (!getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true, IsBool)) 1685 return true; 1686 1687 auto &Ctx = getLLVMContext(); 1688 SanitizerScope SanScope(this); 1689 llvm::Value *Check; 1690 --End; 1691 if (!Min) { 1692 Check = Builder.CreateICmpULE(Value, llvm::ConstantInt::get(Ctx, End)); 1693 } else { 1694 llvm::Value *Upper = 1695 Builder.CreateICmpSLE(Value, llvm::ConstantInt::get(Ctx, End)); 1696 llvm::Value *Lower = 1697 Builder.CreateICmpSGE(Value, llvm::ConstantInt::get(Ctx, Min)); 1698 Check = Builder.CreateAnd(Upper, Lower); 1699 } 1700 llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc), 1701 EmitCheckTypeDescriptor(Ty)}; 1702 SanitizerMask Kind = 1703 NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool; 1704 EmitCheck(std::make_pair(Check, Kind), SanitizerHandler::LoadInvalidValue, 1705 StaticArgs, EmitCheckValue(Value)); 1706 return true; 1707 } 1708 1709 llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile, 1710 QualType Ty, 1711 SourceLocation Loc, 1712 LValueBaseInfo BaseInfo, 1713 TBAAAccessInfo TBAAInfo, 1714 bool isNontemporal) { 1715 if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr.getPointer())) 1716 if (GV->isThreadLocal()) 1717 Addr = Addr.withPointer(Builder.CreateThreadLocalAddress(GV), 1718 NotKnownNonNull); 1719 1720 if (const auto *ClangVecTy = Ty->getAs<VectorType>()) { 1721 // Boolean vectors use `iN` as storage type. 1722 if (ClangVecTy->isExtVectorBoolType()) { 1723 llvm::Type *ValTy = ConvertType(Ty); 1724 unsigned ValNumElems = 1725 cast<llvm::FixedVectorType>(ValTy)->getNumElements(); 1726 // Load the `iP` storage object (P is the padded vector size). 1727 auto *RawIntV = Builder.CreateLoad(Addr, Volatile, "load_bits"); 1728 const auto *RawIntTy = RawIntV->getType(); 1729 assert(RawIntTy->isIntegerTy() && "compressed iN storage for bitvectors"); 1730 // Bitcast iP --> <P x i1>. 1731 auto *PaddedVecTy = llvm::FixedVectorType::get( 1732 Builder.getInt1Ty(), RawIntTy->getPrimitiveSizeInBits()); 1733 llvm::Value *V = Builder.CreateBitCast(RawIntV, PaddedVecTy); 1734 // Shuffle <P x i1> --> <N x i1> (N is the actual bit size). 1735 V = emitBoolVecConversion(V, ValNumElems, "extractvec"); 1736 1737 return EmitFromMemory(V, Ty); 1738 } 1739 1740 // Handle vectors of size 3 like size 4 for better performance. 1741 const llvm::Type *EltTy = Addr.getElementType(); 1742 const auto *VTy = cast<llvm::FixedVectorType>(EltTy); 1743 1744 if (!CGM.getCodeGenOpts().PreserveVec3Type && VTy->getNumElements() == 3) { 1745 1746 llvm::VectorType *vec4Ty = 1747 llvm::FixedVectorType::get(VTy->getElementType(), 4); 1748 Address Cast = Addr.withElementType(vec4Ty); 1749 // Now load value. 1750 llvm::Value *V = Builder.CreateLoad(Cast, Volatile, "loadVec4"); 1751 1752 // Shuffle vector to get vec3. 1753 V = Builder.CreateShuffleVector(V, ArrayRef<int>{0, 1, 2}, "extractVec"); 1754 return EmitFromMemory(V, Ty); 1755 } 1756 } 1757 1758 // Atomic operations have to be done on integral types. 1759 LValue AtomicLValue = 1760 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo); 1761 if (Ty->isAtomicType() || LValueIsSuitableForInlineAtomic(AtomicLValue)) { 1762 return EmitAtomicLoad(AtomicLValue, Loc).getScalarVal(); 1763 } 1764 1765 llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile); 1766 if (isNontemporal) { 1767 llvm::MDNode *Node = llvm::MDNode::get( 1768 Load->getContext(), llvm::ConstantAsMetadata::get(Builder.getInt32(1))); 1769 Load->setMetadata(llvm::LLVMContext::MD_nontemporal, Node); 1770 } 1771 1772 CGM.DecorateInstructionWithTBAA(Load, TBAAInfo); 1773 1774 if (EmitScalarRangeCheck(Load, Ty, Loc)) { 1775 // In order to prevent the optimizer from throwing away the check, don't 1776 // attach range metadata to the load. 1777 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0) 1778 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty)) { 1779 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo); 1780 Load->setMetadata(llvm::LLVMContext::MD_noundef, 1781 llvm::MDNode::get(getLLVMContext(), std::nullopt)); 1782 } 1783 1784 return EmitFromMemory(Load, Ty); 1785 } 1786 1787 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) { 1788 // Bool has a different representation in memory than in registers. 1789 if (hasBooleanRepresentation(Ty)) { 1790 // This should really always be an i1, but sometimes it's already 1791 // an i8, and it's awkward to track those cases down. 1792 if (Value->getType()->isIntegerTy(1)) 1793 return Builder.CreateZExt(Value, ConvertTypeForMem(Ty), "frombool"); 1794 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) && 1795 "wrong value rep of bool"); 1796 } 1797 1798 return Value; 1799 } 1800 1801 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) { 1802 // Bool has a different representation in memory than in registers. 1803 if (hasBooleanRepresentation(Ty)) { 1804 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) && 1805 "wrong value rep of bool"); 1806 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool"); 1807 } 1808 if (Ty->isExtVectorBoolType()) { 1809 const auto *RawIntTy = Value->getType(); 1810 // Bitcast iP --> <P x i1>. 1811 auto *PaddedVecTy = llvm::FixedVectorType::get( 1812 Builder.getInt1Ty(), RawIntTy->getPrimitiveSizeInBits()); 1813 auto *V = Builder.CreateBitCast(Value, PaddedVecTy); 1814 // Shuffle <P x i1> --> <N x i1> (N is the actual bit size). 1815 llvm::Type *ValTy = ConvertType(Ty); 1816 unsigned ValNumElems = cast<llvm::FixedVectorType>(ValTy)->getNumElements(); 1817 return emitBoolVecConversion(V, ValNumElems, "extractvec"); 1818 } 1819 1820 return Value; 1821 } 1822 1823 // Convert the pointer of \p Addr to a pointer to a vector (the value type of 1824 // MatrixType), if it points to a array (the memory type of MatrixType). 1825 static Address MaybeConvertMatrixAddress(Address Addr, CodeGenFunction &CGF, 1826 bool IsVector = true) { 1827 auto *ArrayTy = dyn_cast<llvm::ArrayType>(Addr.getElementType()); 1828 if (ArrayTy && IsVector) { 1829 auto *VectorTy = llvm::FixedVectorType::get(ArrayTy->getElementType(), 1830 ArrayTy->getNumElements()); 1831 1832 return Addr.withElementType(VectorTy); 1833 } 1834 auto *VectorTy = dyn_cast<llvm::VectorType>(Addr.getElementType()); 1835 if (VectorTy && !IsVector) { 1836 auto *ArrayTy = llvm::ArrayType::get( 1837 VectorTy->getElementType(), 1838 cast<llvm::FixedVectorType>(VectorTy)->getNumElements()); 1839 1840 return Addr.withElementType(ArrayTy); 1841 } 1842 1843 return Addr; 1844 } 1845 1846 // Emit a store of a matrix LValue. This may require casting the original 1847 // pointer to memory address (ArrayType) to a pointer to the value type 1848 // (VectorType). 1849 static void EmitStoreOfMatrixScalar(llvm::Value *value, LValue lvalue, 1850 bool isInit, CodeGenFunction &CGF) { 1851 Address Addr = MaybeConvertMatrixAddress(lvalue.getAddress(CGF), CGF, 1852 value->getType()->isVectorTy()); 1853 CGF.EmitStoreOfScalar(value, Addr, lvalue.isVolatile(), lvalue.getType(), 1854 lvalue.getBaseInfo(), lvalue.getTBAAInfo(), isInit, 1855 lvalue.isNontemporal()); 1856 } 1857 1858 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr, 1859 bool Volatile, QualType Ty, 1860 LValueBaseInfo BaseInfo, 1861 TBAAAccessInfo TBAAInfo, 1862 bool isInit, bool isNontemporal) { 1863 if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr.getPointer())) 1864 if (GV->isThreadLocal()) 1865 Addr = Addr.withPointer(Builder.CreateThreadLocalAddress(GV), 1866 NotKnownNonNull); 1867 1868 llvm::Type *SrcTy = Value->getType(); 1869 if (const auto *ClangVecTy = Ty->getAs<VectorType>()) { 1870 auto *VecTy = dyn_cast<llvm::FixedVectorType>(SrcTy); 1871 if (VecTy && ClangVecTy->isExtVectorBoolType()) { 1872 auto *MemIntTy = cast<llvm::IntegerType>(Addr.getElementType()); 1873 // Expand to the memory bit width. 1874 unsigned MemNumElems = MemIntTy->getPrimitiveSizeInBits(); 1875 // <N x i1> --> <P x i1>. 1876 Value = emitBoolVecConversion(Value, MemNumElems, "insertvec"); 1877 // <P x i1> --> iP. 1878 Value = Builder.CreateBitCast(Value, MemIntTy); 1879 } else if (!CGM.getCodeGenOpts().PreserveVec3Type) { 1880 // Handle vec3 special. 1881 if (VecTy && cast<llvm::FixedVectorType>(VecTy)->getNumElements() == 3) { 1882 // Our source is a vec3, do a shuffle vector to make it a vec4. 1883 Value = Builder.CreateShuffleVector(Value, ArrayRef<int>{0, 1, 2, -1}, 1884 "extractVec"); 1885 SrcTy = llvm::FixedVectorType::get(VecTy->getElementType(), 4); 1886 } 1887 if (Addr.getElementType() != SrcTy) { 1888 Addr = Addr.withElementType(SrcTy); 1889 } 1890 } 1891 } 1892 1893 Value = EmitToMemory(Value, Ty); 1894 1895 LValue AtomicLValue = 1896 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo); 1897 if (Ty->isAtomicType() || 1898 (!isInit && LValueIsSuitableForInlineAtomic(AtomicLValue))) { 1899 EmitAtomicStore(RValue::get(Value), AtomicLValue, isInit); 1900 return; 1901 } 1902 1903 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile); 1904 if (isNontemporal) { 1905 llvm::MDNode *Node = 1906 llvm::MDNode::get(Store->getContext(), 1907 llvm::ConstantAsMetadata::get(Builder.getInt32(1))); 1908 Store->setMetadata(llvm::LLVMContext::MD_nontemporal, Node); 1909 } 1910 1911 CGM.DecorateInstructionWithTBAA(Store, TBAAInfo); 1912 } 1913 1914 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue, 1915 bool isInit) { 1916 if (lvalue.getType()->isConstantMatrixType()) { 1917 EmitStoreOfMatrixScalar(value, lvalue, isInit, *this); 1918 return; 1919 } 1920 1921 EmitStoreOfScalar(value, lvalue.getAddress(*this), lvalue.isVolatile(), 1922 lvalue.getType(), lvalue.getBaseInfo(), 1923 lvalue.getTBAAInfo(), isInit, lvalue.isNontemporal()); 1924 } 1925 1926 // Emit a load of a LValue of matrix type. This may require casting the pointer 1927 // to memory address (ArrayType) to a pointer to the value type (VectorType). 1928 static RValue EmitLoadOfMatrixLValue(LValue LV, SourceLocation Loc, 1929 CodeGenFunction &CGF) { 1930 assert(LV.getType()->isConstantMatrixType()); 1931 Address Addr = MaybeConvertMatrixAddress(LV.getAddress(CGF), CGF); 1932 LV.setAddress(Addr); 1933 return RValue::get(CGF.EmitLoadOfScalar(LV, Loc)); 1934 } 1935 1936 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this 1937 /// method emits the address of the lvalue, then loads the result as an rvalue, 1938 /// returning the rvalue. 1939 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) { 1940 if (LV.isObjCWeak()) { 1941 // load of a __weak object. 1942 Address AddrWeakObj = LV.getAddress(*this); 1943 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this, 1944 AddrWeakObj)); 1945 } 1946 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) { 1947 // In MRC mode, we do a load+autorelease. 1948 if (!getLangOpts().ObjCAutoRefCount) { 1949 return RValue::get(EmitARCLoadWeak(LV.getAddress(*this))); 1950 } 1951 1952 // In ARC mode, we load retained and then consume the value. 1953 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress(*this)); 1954 Object = EmitObjCConsumeObject(LV.getType(), Object); 1955 return RValue::get(Object); 1956 } 1957 1958 if (LV.isSimple()) { 1959 assert(!LV.getType()->isFunctionType()); 1960 1961 if (LV.getType()->isConstantMatrixType()) 1962 return EmitLoadOfMatrixLValue(LV, Loc, *this); 1963 1964 // Everything needs a load. 1965 return RValue::get(EmitLoadOfScalar(LV, Loc)); 1966 } 1967 1968 if (LV.isVectorElt()) { 1969 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddress(), 1970 LV.isVolatileQualified()); 1971 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(), 1972 "vecext")); 1973 } 1974 1975 // If this is a reference to a subset of the elements of a vector, either 1976 // shuffle the input or extract/insert them as appropriate. 1977 if (LV.isExtVectorElt()) { 1978 return EmitLoadOfExtVectorElementLValue(LV); 1979 } 1980 1981 // Global Register variables always invoke intrinsics 1982 if (LV.isGlobalReg()) 1983 return EmitLoadOfGlobalRegLValue(LV); 1984 1985 if (LV.isMatrixElt()) { 1986 llvm::Value *Idx = LV.getMatrixIdx(); 1987 if (CGM.getCodeGenOpts().OptimizationLevel > 0) { 1988 const auto *const MatTy = LV.getType()->castAs<ConstantMatrixType>(); 1989 llvm::MatrixBuilder MB(Builder); 1990 MB.CreateIndexAssumption(Idx, MatTy->getNumElementsFlattened()); 1991 } 1992 llvm::LoadInst *Load = 1993 Builder.CreateLoad(LV.getMatrixAddress(), LV.isVolatileQualified()); 1994 return RValue::get(Builder.CreateExtractElement(Load, Idx, "matrixext")); 1995 } 1996 1997 assert(LV.isBitField() && "Unknown LValue type!"); 1998 return EmitLoadOfBitfieldLValue(LV, Loc); 1999 } 2000 2001 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV, 2002 SourceLocation Loc) { 2003 const CGBitFieldInfo &Info = LV.getBitFieldInfo(); 2004 2005 // Get the output type. 2006 llvm::Type *ResLTy = ConvertType(LV.getType()); 2007 2008 Address Ptr = LV.getBitFieldAddress(); 2009 llvm::Value *Val = 2010 Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "bf.load"); 2011 2012 bool UseVolatile = LV.isVolatileQualified() && 2013 Info.VolatileStorageSize != 0 && isAAPCS(CGM.getTarget()); 2014 const unsigned Offset = UseVolatile ? Info.VolatileOffset : Info.Offset; 2015 const unsigned StorageSize = 2016 UseVolatile ? Info.VolatileStorageSize : Info.StorageSize; 2017 if (Info.IsSigned) { 2018 assert(static_cast<unsigned>(Offset + Info.Size) <= StorageSize); 2019 unsigned HighBits = StorageSize - Offset - Info.Size; 2020 if (HighBits) 2021 Val = Builder.CreateShl(Val, HighBits, "bf.shl"); 2022 if (Offset + HighBits) 2023 Val = Builder.CreateAShr(Val, Offset + HighBits, "bf.ashr"); 2024 } else { 2025 if (Offset) 2026 Val = Builder.CreateLShr(Val, Offset, "bf.lshr"); 2027 if (static_cast<unsigned>(Offset) + Info.Size < StorageSize) 2028 Val = Builder.CreateAnd( 2029 Val, llvm::APInt::getLowBitsSet(StorageSize, Info.Size), "bf.clear"); 2030 } 2031 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast"); 2032 EmitScalarRangeCheck(Val, LV.getType(), Loc); 2033 return RValue::get(Val); 2034 } 2035 2036 // If this is a reference to a subset of the elements of a vector, create an 2037 // appropriate shufflevector. 2038 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) { 2039 llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddress(), 2040 LV.isVolatileQualified()); 2041 2042 const llvm::Constant *Elts = LV.getExtVectorElts(); 2043 2044 // If the result of the expression is a non-vector type, we must be extracting 2045 // a single element. Just codegen as an extractelement. 2046 const VectorType *ExprVT = LV.getType()->getAs<VectorType>(); 2047 if (!ExprVT) { 2048 unsigned InIdx = getAccessedFieldNo(0, Elts); 2049 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx); 2050 return RValue::get(Builder.CreateExtractElement(Vec, Elt)); 2051 } 2052 2053 // Always use shuffle vector to try to retain the original program structure 2054 unsigned NumResultElts = ExprVT->getNumElements(); 2055 2056 SmallVector<int, 4> Mask; 2057 for (unsigned i = 0; i != NumResultElts; ++i) 2058 Mask.push_back(getAccessedFieldNo(i, Elts)); 2059 2060 Vec = Builder.CreateShuffleVector(Vec, Mask); 2061 return RValue::get(Vec); 2062 } 2063 2064 /// Generates lvalue for partial ext_vector access. 2065 Address CodeGenFunction::EmitExtVectorElementLValue(LValue LV) { 2066 Address VectorAddress = LV.getExtVectorAddress(); 2067 QualType EQT = LV.getType()->castAs<VectorType>()->getElementType(); 2068 llvm::Type *VectorElementTy = CGM.getTypes().ConvertType(EQT); 2069 2070 Address CastToPointerElement = VectorAddress.withElementType(VectorElementTy); 2071 2072 const llvm::Constant *Elts = LV.getExtVectorElts(); 2073 unsigned ix = getAccessedFieldNo(0, Elts); 2074 2075 Address VectorBasePtrPlusIx = 2076 Builder.CreateConstInBoundsGEP(CastToPointerElement, ix, 2077 "vector.elt"); 2078 2079 return VectorBasePtrPlusIx; 2080 } 2081 2082 /// Load of global gamed gegisters are always calls to intrinsics. 2083 RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) { 2084 assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) && 2085 "Bad type for register variable"); 2086 llvm::MDNode *RegName = cast<llvm::MDNode>( 2087 cast<llvm::MetadataAsValue>(LV.getGlobalReg())->getMetadata()); 2088 2089 // We accept integer and pointer types only 2090 llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType()); 2091 llvm::Type *Ty = OrigTy; 2092 if (OrigTy->isPointerTy()) 2093 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy); 2094 llvm::Type *Types[] = { Ty }; 2095 2096 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types); 2097 llvm::Value *Call = Builder.CreateCall( 2098 F, llvm::MetadataAsValue::get(Ty->getContext(), RegName)); 2099 if (OrigTy->isPointerTy()) 2100 Call = Builder.CreateIntToPtr(Call, OrigTy); 2101 return RValue::get(Call); 2102 } 2103 2104 /// EmitStoreThroughLValue - Store the specified rvalue into the specified 2105 /// lvalue, where both are guaranteed to the have the same type, and that type 2106 /// is 'Ty'. 2107 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst, 2108 bool isInit) { 2109 if (!Dst.isSimple()) { 2110 if (Dst.isVectorElt()) { 2111 // Read/modify/write the vector, inserting the new element. 2112 llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddress(), 2113 Dst.isVolatileQualified()); 2114 auto *IRStoreTy = dyn_cast<llvm::IntegerType>(Vec->getType()); 2115 if (IRStoreTy) { 2116 auto *IRVecTy = llvm::FixedVectorType::get( 2117 Builder.getInt1Ty(), IRStoreTy->getPrimitiveSizeInBits()); 2118 Vec = Builder.CreateBitCast(Vec, IRVecTy); 2119 // iN --> <N x i1>. 2120 } 2121 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(), 2122 Dst.getVectorIdx(), "vecins"); 2123 if (IRStoreTy) { 2124 // <N x i1> --> <iN>. 2125 Vec = Builder.CreateBitCast(Vec, IRStoreTy); 2126 } 2127 Builder.CreateStore(Vec, Dst.getVectorAddress(), 2128 Dst.isVolatileQualified()); 2129 return; 2130 } 2131 2132 // If this is an update of extended vector elements, insert them as 2133 // appropriate. 2134 if (Dst.isExtVectorElt()) 2135 return EmitStoreThroughExtVectorComponentLValue(Src, Dst); 2136 2137 if (Dst.isGlobalReg()) 2138 return EmitStoreThroughGlobalRegLValue(Src, Dst); 2139 2140 if (Dst.isMatrixElt()) { 2141 llvm::Value *Idx = Dst.getMatrixIdx(); 2142 if (CGM.getCodeGenOpts().OptimizationLevel > 0) { 2143 const auto *const MatTy = Dst.getType()->castAs<ConstantMatrixType>(); 2144 llvm::MatrixBuilder MB(Builder); 2145 MB.CreateIndexAssumption(Idx, MatTy->getNumElementsFlattened()); 2146 } 2147 llvm::Instruction *Load = Builder.CreateLoad(Dst.getMatrixAddress()); 2148 llvm::Value *Vec = 2149 Builder.CreateInsertElement(Load, Src.getScalarVal(), Idx, "matins"); 2150 Builder.CreateStore(Vec, Dst.getMatrixAddress(), 2151 Dst.isVolatileQualified()); 2152 return; 2153 } 2154 2155 assert(Dst.isBitField() && "Unknown LValue type"); 2156 return EmitStoreThroughBitfieldLValue(Src, Dst); 2157 } 2158 2159 // There's special magic for assigning into an ARC-qualified l-value. 2160 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) { 2161 switch (Lifetime) { 2162 case Qualifiers::OCL_None: 2163 llvm_unreachable("present but none"); 2164 2165 case Qualifiers::OCL_ExplicitNone: 2166 // nothing special 2167 break; 2168 2169 case Qualifiers::OCL_Strong: 2170 if (isInit) { 2171 Src = RValue::get(EmitARCRetain(Dst.getType(), Src.getScalarVal())); 2172 break; 2173 } 2174 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true); 2175 return; 2176 2177 case Qualifiers::OCL_Weak: 2178 if (isInit) 2179 // Initialize and then skip the primitive store. 2180 EmitARCInitWeak(Dst.getAddress(*this), Src.getScalarVal()); 2181 else 2182 EmitARCStoreWeak(Dst.getAddress(*this), Src.getScalarVal(), 2183 /*ignore*/ true); 2184 return; 2185 2186 case Qualifiers::OCL_Autoreleasing: 2187 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(), 2188 Src.getScalarVal())); 2189 // fall into the normal path 2190 break; 2191 } 2192 } 2193 2194 if (Dst.isObjCWeak() && !Dst.isNonGC()) { 2195 // load of a __weak object. 2196 Address LvalueDst = Dst.getAddress(*this); 2197 llvm::Value *src = Src.getScalarVal(); 2198 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst); 2199 return; 2200 } 2201 2202 if (Dst.isObjCStrong() && !Dst.isNonGC()) { 2203 // load of a __strong object. 2204 Address LvalueDst = Dst.getAddress(*this); 2205 llvm::Value *src = Src.getScalarVal(); 2206 if (Dst.isObjCIvar()) { 2207 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL"); 2208 llvm::Type *ResultType = IntPtrTy; 2209 Address dst = EmitPointerWithAlignment(Dst.getBaseIvarExp()); 2210 llvm::Value *RHS = dst.getPointer(); 2211 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 2212 llvm::Value *LHS = 2213 Builder.CreatePtrToInt(LvalueDst.getPointer(), ResultType, 2214 "sub.ptr.lhs.cast"); 2215 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset"); 2216 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst, 2217 BytesBetween); 2218 } else if (Dst.isGlobalObjCRef()) { 2219 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst, 2220 Dst.isThreadLocalRef()); 2221 } 2222 else 2223 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst); 2224 return; 2225 } 2226 2227 assert(Src.isScalar() && "Can't emit an agg store with this method"); 2228 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit); 2229 } 2230 2231 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst, 2232 llvm::Value **Result) { 2233 const CGBitFieldInfo &Info = Dst.getBitFieldInfo(); 2234 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType()); 2235 Address Ptr = Dst.getBitFieldAddress(); 2236 2237 // Get the source value, truncated to the width of the bit-field. 2238 llvm::Value *SrcVal = Src.getScalarVal(); 2239 2240 // Cast the source to the storage type and shift it into place. 2241 SrcVal = Builder.CreateIntCast(SrcVal, Ptr.getElementType(), 2242 /*isSigned=*/false); 2243 llvm::Value *MaskedVal = SrcVal; 2244 2245 const bool UseVolatile = 2246 CGM.getCodeGenOpts().AAPCSBitfieldWidth && Dst.isVolatileQualified() && 2247 Info.VolatileStorageSize != 0 && isAAPCS(CGM.getTarget()); 2248 const unsigned StorageSize = 2249 UseVolatile ? Info.VolatileStorageSize : Info.StorageSize; 2250 const unsigned Offset = UseVolatile ? Info.VolatileOffset : Info.Offset; 2251 // See if there are other bits in the bitfield's storage we'll need to load 2252 // and mask together with source before storing. 2253 if (StorageSize != Info.Size) { 2254 assert(StorageSize > Info.Size && "Invalid bitfield size."); 2255 llvm::Value *Val = 2256 Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.load"); 2257 2258 // Mask the source value as needed. 2259 if (!hasBooleanRepresentation(Dst.getType())) 2260 SrcVal = Builder.CreateAnd( 2261 SrcVal, llvm::APInt::getLowBitsSet(StorageSize, Info.Size), 2262 "bf.value"); 2263 MaskedVal = SrcVal; 2264 if (Offset) 2265 SrcVal = Builder.CreateShl(SrcVal, Offset, "bf.shl"); 2266 2267 // Mask out the original value. 2268 Val = Builder.CreateAnd( 2269 Val, ~llvm::APInt::getBitsSet(StorageSize, Offset, Offset + Info.Size), 2270 "bf.clear"); 2271 2272 // Or together the unchanged values and the source value. 2273 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set"); 2274 } else { 2275 assert(Offset == 0); 2276 // According to the AACPS: 2277 // When a volatile bit-field is written, and its container does not overlap 2278 // with any non-bit-field member, its container must be read exactly once 2279 // and written exactly once using the access width appropriate to the type 2280 // of the container. The two accesses are not atomic. 2281 if (Dst.isVolatileQualified() && isAAPCS(CGM.getTarget()) && 2282 CGM.getCodeGenOpts().ForceAAPCSBitfieldLoad) 2283 Builder.CreateLoad(Ptr, true, "bf.load"); 2284 } 2285 2286 // Write the new value back out. 2287 Builder.CreateStore(SrcVal, Ptr, Dst.isVolatileQualified()); 2288 2289 // Return the new value of the bit-field, if requested. 2290 if (Result) { 2291 llvm::Value *ResultVal = MaskedVal; 2292 2293 // Sign extend the value if needed. 2294 if (Info.IsSigned) { 2295 assert(Info.Size <= StorageSize); 2296 unsigned HighBits = StorageSize - Info.Size; 2297 if (HighBits) { 2298 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl"); 2299 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr"); 2300 } 2301 } 2302 2303 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned, 2304 "bf.result.cast"); 2305 *Result = EmitFromMemory(ResultVal, Dst.getType()); 2306 } 2307 } 2308 2309 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src, 2310 LValue Dst) { 2311 // This access turns into a read/modify/write of the vector. Load the input 2312 // value now. 2313 llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddress(), 2314 Dst.isVolatileQualified()); 2315 const llvm::Constant *Elts = Dst.getExtVectorElts(); 2316 2317 llvm::Value *SrcVal = Src.getScalarVal(); 2318 2319 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) { 2320 unsigned NumSrcElts = VTy->getNumElements(); 2321 unsigned NumDstElts = 2322 cast<llvm::FixedVectorType>(Vec->getType())->getNumElements(); 2323 if (NumDstElts == NumSrcElts) { 2324 // Use shuffle vector is the src and destination are the same number of 2325 // elements and restore the vector mask since it is on the side it will be 2326 // stored. 2327 SmallVector<int, 4> Mask(NumDstElts); 2328 for (unsigned i = 0; i != NumSrcElts; ++i) 2329 Mask[getAccessedFieldNo(i, Elts)] = i; 2330 2331 Vec = Builder.CreateShuffleVector(SrcVal, Mask); 2332 } else if (NumDstElts > NumSrcElts) { 2333 // Extended the source vector to the same length and then shuffle it 2334 // into the destination. 2335 // FIXME: since we're shuffling with undef, can we just use the indices 2336 // into that? This could be simpler. 2337 SmallVector<int, 4> ExtMask; 2338 for (unsigned i = 0; i != NumSrcElts; ++i) 2339 ExtMask.push_back(i); 2340 ExtMask.resize(NumDstElts, -1); 2341 llvm::Value *ExtSrcVal = Builder.CreateShuffleVector(SrcVal, ExtMask); 2342 // build identity 2343 SmallVector<int, 4> Mask; 2344 for (unsigned i = 0; i != NumDstElts; ++i) 2345 Mask.push_back(i); 2346 2347 // When the vector size is odd and .odd or .hi is used, the last element 2348 // of the Elts constant array will be one past the size of the vector. 2349 // Ignore the last element here, if it is greater than the mask size. 2350 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size()) 2351 NumSrcElts--; 2352 2353 // modify when what gets shuffled in 2354 for (unsigned i = 0; i != NumSrcElts; ++i) 2355 Mask[getAccessedFieldNo(i, Elts)] = i + NumDstElts; 2356 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, Mask); 2357 } else { 2358 // We should never shorten the vector 2359 llvm_unreachable("unexpected shorten vector length"); 2360 } 2361 } else { 2362 // If the Src is a scalar (not a vector) it must be updating one element. 2363 unsigned InIdx = getAccessedFieldNo(0, Elts); 2364 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx); 2365 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt); 2366 } 2367 2368 Builder.CreateStore(Vec, Dst.getExtVectorAddress(), 2369 Dst.isVolatileQualified()); 2370 } 2371 2372 /// Store of global named registers are always calls to intrinsics. 2373 void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) { 2374 assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) && 2375 "Bad type for register variable"); 2376 llvm::MDNode *RegName = cast<llvm::MDNode>( 2377 cast<llvm::MetadataAsValue>(Dst.getGlobalReg())->getMetadata()); 2378 assert(RegName && "Register LValue is not metadata"); 2379 2380 // We accept integer and pointer types only 2381 llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType()); 2382 llvm::Type *Ty = OrigTy; 2383 if (OrigTy->isPointerTy()) 2384 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy); 2385 llvm::Type *Types[] = { Ty }; 2386 2387 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types); 2388 llvm::Value *Value = Src.getScalarVal(); 2389 if (OrigTy->isPointerTy()) 2390 Value = Builder.CreatePtrToInt(Value, Ty); 2391 Builder.CreateCall( 2392 F, {llvm::MetadataAsValue::get(Ty->getContext(), RegName), Value}); 2393 } 2394 2395 // setObjCGCLValueClass - sets class of the lvalue for the purpose of 2396 // generating write-barries API. It is currently a global, ivar, 2397 // or neither. 2398 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E, 2399 LValue &LV, 2400 bool IsMemberAccess=false) { 2401 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC) 2402 return; 2403 2404 if (isa<ObjCIvarRefExpr>(E)) { 2405 QualType ExpTy = E->getType(); 2406 if (IsMemberAccess && ExpTy->isPointerType()) { 2407 // If ivar is a structure pointer, assigning to field of 2408 // this struct follows gcc's behavior and makes it a non-ivar 2409 // writer-barrier conservatively. 2410 ExpTy = ExpTy->castAs<PointerType>()->getPointeeType(); 2411 if (ExpTy->isRecordType()) { 2412 LV.setObjCIvar(false); 2413 return; 2414 } 2415 } 2416 LV.setObjCIvar(true); 2417 auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E)); 2418 LV.setBaseIvarExp(Exp->getBase()); 2419 LV.setObjCArray(E->getType()->isArrayType()); 2420 return; 2421 } 2422 2423 if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) { 2424 if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) { 2425 if (VD->hasGlobalStorage()) { 2426 LV.setGlobalObjCRef(true); 2427 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None); 2428 } 2429 } 2430 LV.setObjCArray(E->getType()->isArrayType()); 2431 return; 2432 } 2433 2434 if (const auto *Exp = dyn_cast<UnaryOperator>(E)) { 2435 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2436 return; 2437 } 2438 2439 if (const auto *Exp = dyn_cast<ParenExpr>(E)) { 2440 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2441 if (LV.isObjCIvar()) { 2442 // If cast is to a structure pointer, follow gcc's behavior and make it 2443 // a non-ivar write-barrier. 2444 QualType ExpTy = E->getType(); 2445 if (ExpTy->isPointerType()) 2446 ExpTy = ExpTy->castAs<PointerType>()->getPointeeType(); 2447 if (ExpTy->isRecordType()) 2448 LV.setObjCIvar(false); 2449 } 2450 return; 2451 } 2452 2453 if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) { 2454 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV); 2455 return; 2456 } 2457 2458 if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) { 2459 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2460 return; 2461 } 2462 2463 if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) { 2464 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2465 return; 2466 } 2467 2468 if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) { 2469 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2470 return; 2471 } 2472 2473 if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) { 2474 setObjCGCLValueClass(Ctx, Exp->getBase(), LV); 2475 if (LV.isObjCIvar() && !LV.isObjCArray()) 2476 // Using array syntax to assigning to what an ivar points to is not 2477 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0; 2478 LV.setObjCIvar(false); 2479 else if (LV.isGlobalObjCRef() && !LV.isObjCArray()) 2480 // Using array syntax to assigning to what global points to is not 2481 // same as assigning to the global itself. {id *G;} G[i] = 0; 2482 LV.setGlobalObjCRef(false); 2483 return; 2484 } 2485 2486 if (const auto *Exp = dyn_cast<MemberExpr>(E)) { 2487 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true); 2488 // We don't know if member is an 'ivar', but this flag is looked at 2489 // only in the context of LV.isObjCIvar(). 2490 LV.setObjCArray(E->getType()->isArrayType()); 2491 return; 2492 } 2493 } 2494 2495 static llvm::Value * 2496 EmitBitCastOfLValueToProperType(CodeGenFunction &CGF, 2497 llvm::Value *V, llvm::Type *IRType, 2498 StringRef Name = StringRef()) { 2499 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace(); 2500 return CGF.Builder.CreateBitCast(V, IRType->getPointerTo(AS), Name); 2501 } 2502 2503 static LValue EmitThreadPrivateVarDeclLValue( 2504 CodeGenFunction &CGF, const VarDecl *VD, QualType T, Address Addr, 2505 llvm::Type *RealVarTy, SourceLocation Loc) { 2506 if (CGF.CGM.getLangOpts().OpenMPIRBuilder) 2507 Addr = CodeGenFunction::OMPBuilderCBHelpers::getAddrOfThreadPrivate( 2508 CGF, VD, Addr, Loc); 2509 else 2510 Addr = 2511 CGF.CGM.getOpenMPRuntime().getAddrOfThreadPrivate(CGF, VD, Addr, Loc); 2512 2513 Addr = Addr.withElementType(RealVarTy); 2514 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl); 2515 } 2516 2517 static Address emitDeclTargetVarDeclLValue(CodeGenFunction &CGF, 2518 const VarDecl *VD, QualType T) { 2519 std::optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res = 2520 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD); 2521 // Return an invalid address if variable is MT_To (or MT_Enter starting with 2522 // OpenMP 5.2) and unified memory is not enabled. For all other cases: MT_Link 2523 // and MT_To (or MT_Enter) with unified memory, return a valid address. 2524 if (!Res || ((*Res == OMPDeclareTargetDeclAttr::MT_To || 2525 *Res == OMPDeclareTargetDeclAttr::MT_Enter) && 2526 !CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory())) 2527 return Address::invalid(); 2528 assert(((*Res == OMPDeclareTargetDeclAttr::MT_Link) || 2529 ((*Res == OMPDeclareTargetDeclAttr::MT_To || 2530 *Res == OMPDeclareTargetDeclAttr::MT_Enter) && 2531 CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory())) && 2532 "Expected link clause OR to clause with unified memory enabled."); 2533 QualType PtrTy = CGF.getContext().getPointerType(VD->getType()); 2534 Address Addr = CGF.CGM.getOpenMPRuntime().getAddrOfDeclareTargetVar(VD); 2535 return CGF.EmitLoadOfPointer(Addr, PtrTy->castAs<PointerType>()); 2536 } 2537 2538 Address 2539 CodeGenFunction::EmitLoadOfReference(LValue RefLVal, 2540 LValueBaseInfo *PointeeBaseInfo, 2541 TBAAAccessInfo *PointeeTBAAInfo) { 2542 llvm::LoadInst *Load = 2543 Builder.CreateLoad(RefLVal.getAddress(*this), RefLVal.isVolatile()); 2544 CGM.DecorateInstructionWithTBAA(Load, RefLVal.getTBAAInfo()); 2545 2546 QualType PointeeType = RefLVal.getType()->getPointeeType(); 2547 CharUnits Align = CGM.getNaturalTypeAlignment( 2548 PointeeType, PointeeBaseInfo, PointeeTBAAInfo, 2549 /* forPointeeType= */ true); 2550 return Address(Load, ConvertTypeForMem(PointeeType), Align); 2551 } 2552 2553 LValue CodeGenFunction::EmitLoadOfReferenceLValue(LValue RefLVal) { 2554 LValueBaseInfo PointeeBaseInfo; 2555 TBAAAccessInfo PointeeTBAAInfo; 2556 Address PointeeAddr = EmitLoadOfReference(RefLVal, &PointeeBaseInfo, 2557 &PointeeTBAAInfo); 2558 return MakeAddrLValue(PointeeAddr, RefLVal.getType()->getPointeeType(), 2559 PointeeBaseInfo, PointeeTBAAInfo); 2560 } 2561 2562 Address CodeGenFunction::EmitLoadOfPointer(Address Ptr, 2563 const PointerType *PtrTy, 2564 LValueBaseInfo *BaseInfo, 2565 TBAAAccessInfo *TBAAInfo) { 2566 llvm::Value *Addr = Builder.CreateLoad(Ptr); 2567 return Address(Addr, ConvertTypeForMem(PtrTy->getPointeeType()), 2568 CGM.getNaturalTypeAlignment(PtrTy->getPointeeType(), BaseInfo, 2569 TBAAInfo, 2570 /*forPointeeType=*/true)); 2571 } 2572 2573 LValue CodeGenFunction::EmitLoadOfPointerLValue(Address PtrAddr, 2574 const PointerType *PtrTy) { 2575 LValueBaseInfo BaseInfo; 2576 TBAAAccessInfo TBAAInfo; 2577 Address Addr = EmitLoadOfPointer(PtrAddr, PtrTy, &BaseInfo, &TBAAInfo); 2578 return MakeAddrLValue(Addr, PtrTy->getPointeeType(), BaseInfo, TBAAInfo); 2579 } 2580 2581 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF, 2582 const Expr *E, const VarDecl *VD) { 2583 QualType T = E->getType(); 2584 2585 // If it's thread_local, emit a call to its wrapper function instead. 2586 if (VD->getTLSKind() == VarDecl::TLS_Dynamic && 2587 CGF.CGM.getCXXABI().usesThreadWrapperFunction(VD)) 2588 return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T); 2589 // Check if the variable is marked as declare target with link clause in 2590 // device codegen. 2591 if (CGF.getLangOpts().OpenMPIsTargetDevice) { 2592 Address Addr = emitDeclTargetVarDeclLValue(CGF, VD, T); 2593 if (Addr.isValid()) 2594 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl); 2595 } 2596 2597 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD); 2598 2599 if (VD->getTLSKind() != VarDecl::TLS_None) 2600 V = CGF.Builder.CreateThreadLocalAddress(V); 2601 2602 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType()); 2603 V = EmitBitCastOfLValueToProperType(CGF, V, RealVarTy); 2604 CharUnits Alignment = CGF.getContext().getDeclAlign(VD); 2605 Address Addr(V, RealVarTy, Alignment); 2606 // Emit reference to the private copy of the variable if it is an OpenMP 2607 // threadprivate variable. 2608 if (CGF.getLangOpts().OpenMP && !CGF.getLangOpts().OpenMPSimd && 2609 VD->hasAttr<OMPThreadPrivateDeclAttr>()) { 2610 return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy, 2611 E->getExprLoc()); 2612 } 2613 LValue LV = VD->getType()->isReferenceType() ? 2614 CGF.EmitLoadOfReferenceLValue(Addr, VD->getType(), 2615 AlignmentSource::Decl) : 2616 CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl); 2617 setObjCGCLValueClass(CGF.getContext(), E, LV); 2618 return LV; 2619 } 2620 2621 static llvm::Constant *EmitFunctionDeclPointer(CodeGenModule &CGM, 2622 GlobalDecl GD) { 2623 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 2624 if (FD->hasAttr<WeakRefAttr>()) { 2625 ConstantAddress aliasee = CGM.GetWeakRefReference(FD); 2626 return aliasee.getPointer(); 2627 } 2628 2629 llvm::Constant *V = CGM.GetAddrOfFunction(GD); 2630 if (!FD->hasPrototype()) { 2631 if (const FunctionProtoType *Proto = 2632 FD->getType()->getAs<FunctionProtoType>()) { 2633 // Ugly case: for a K&R-style definition, the type of the definition 2634 // isn't the same as the type of a use. Correct for this with a 2635 // bitcast. 2636 QualType NoProtoType = 2637 CGM.getContext().getFunctionNoProtoType(Proto->getReturnType()); 2638 NoProtoType = CGM.getContext().getPointerType(NoProtoType); 2639 V = llvm::ConstantExpr::getBitCast(V, 2640 CGM.getTypes().ConvertType(NoProtoType)); 2641 } 2642 } 2643 return V; 2644 } 2645 2646 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF, const Expr *E, 2647 GlobalDecl GD) { 2648 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 2649 llvm::Value *V = EmitFunctionDeclPointer(CGF.CGM, GD); 2650 CharUnits Alignment = CGF.getContext().getDeclAlign(FD); 2651 return CGF.MakeAddrLValue(V, E->getType(), Alignment, 2652 AlignmentSource::Decl); 2653 } 2654 2655 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD, 2656 llvm::Value *ThisValue) { 2657 QualType TagType = CGF.getContext().getTagDeclType(FD->getParent()); 2658 LValue LV = CGF.MakeNaturalAlignAddrLValue(ThisValue, TagType); 2659 return CGF.EmitLValueForField(LV, FD); 2660 } 2661 2662 /// Named Registers are named metadata pointing to the register name 2663 /// which will be read from/written to as an argument to the intrinsic 2664 /// @llvm.read/write_register. 2665 /// So far, only the name is being passed down, but other options such as 2666 /// register type, allocation type or even optimization options could be 2667 /// passed down via the metadata node. 2668 static LValue EmitGlobalNamedRegister(const VarDecl *VD, CodeGenModule &CGM) { 2669 SmallString<64> Name("llvm.named.register."); 2670 AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>(); 2671 assert(Asm->getLabel().size() < 64-Name.size() && 2672 "Register name too big"); 2673 Name.append(Asm->getLabel()); 2674 llvm::NamedMDNode *M = 2675 CGM.getModule().getOrInsertNamedMetadata(Name); 2676 if (M->getNumOperands() == 0) { 2677 llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(), 2678 Asm->getLabel()); 2679 llvm::Metadata *Ops[] = {Str}; 2680 M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops)); 2681 } 2682 2683 CharUnits Alignment = CGM.getContext().getDeclAlign(VD); 2684 2685 llvm::Value *Ptr = 2686 llvm::MetadataAsValue::get(CGM.getLLVMContext(), M->getOperand(0)); 2687 return LValue::MakeGlobalReg(Ptr, Alignment, VD->getType()); 2688 } 2689 2690 /// Determine whether we can emit a reference to \p VD from the current 2691 /// context, despite not necessarily having seen an odr-use of the variable in 2692 /// this context. 2693 static bool canEmitSpuriousReferenceToVariable(CodeGenFunction &CGF, 2694 const DeclRefExpr *E, 2695 const VarDecl *VD, 2696 bool IsConstant) { 2697 // For a variable declared in an enclosing scope, do not emit a spurious 2698 // reference even if we have a capture, as that will emit an unwarranted 2699 // reference to our capture state, and will likely generate worse code than 2700 // emitting a local copy. 2701 if (E->refersToEnclosingVariableOrCapture()) 2702 return false; 2703 2704 // For a local declaration declared in this function, we can always reference 2705 // it even if we don't have an odr-use. 2706 if (VD->hasLocalStorage()) { 2707 return VD->getDeclContext() == 2708 dyn_cast_or_null<DeclContext>(CGF.CurCodeDecl); 2709 } 2710 2711 // For a global declaration, we can emit a reference to it if we know 2712 // for sure that we are able to emit a definition of it. 2713 VD = VD->getDefinition(CGF.getContext()); 2714 if (!VD) 2715 return false; 2716 2717 // Don't emit a spurious reference if it might be to a variable that only 2718 // exists on a different device / target. 2719 // FIXME: This is unnecessarily broad. Check whether this would actually be a 2720 // cross-target reference. 2721 if (CGF.getLangOpts().OpenMP || CGF.getLangOpts().CUDA || 2722 CGF.getLangOpts().OpenCL) { 2723 return false; 2724 } 2725 2726 // We can emit a spurious reference only if the linkage implies that we'll 2727 // be emitting a non-interposable symbol that will be retained until link 2728 // time. 2729 switch (CGF.CGM.getLLVMLinkageVarDefinition(VD, IsConstant)) { 2730 case llvm::GlobalValue::ExternalLinkage: 2731 case llvm::GlobalValue::LinkOnceODRLinkage: 2732 case llvm::GlobalValue::WeakODRLinkage: 2733 case llvm::GlobalValue::InternalLinkage: 2734 case llvm::GlobalValue::PrivateLinkage: 2735 return true; 2736 default: 2737 return false; 2738 } 2739 } 2740 2741 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) { 2742 const NamedDecl *ND = E->getDecl(); 2743 QualType T = E->getType(); 2744 2745 assert(E->isNonOdrUse() != NOUR_Unevaluated && 2746 "should not emit an unevaluated operand"); 2747 2748 if (const auto *VD = dyn_cast<VarDecl>(ND)) { 2749 // Global Named registers access via intrinsics only 2750 if (VD->getStorageClass() == SC_Register && 2751 VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl()) 2752 return EmitGlobalNamedRegister(VD, CGM); 2753 2754 // If this DeclRefExpr does not constitute an odr-use of the variable, 2755 // we're not permitted to emit a reference to it in general, and it might 2756 // not be captured if capture would be necessary for a use. Emit the 2757 // constant value directly instead. 2758 if (E->isNonOdrUse() == NOUR_Constant && 2759 (VD->getType()->isReferenceType() || 2760 !canEmitSpuriousReferenceToVariable(*this, E, VD, true))) { 2761 VD->getAnyInitializer(VD); 2762 llvm::Constant *Val = ConstantEmitter(*this).emitAbstract( 2763 E->getLocation(), *VD->evaluateValue(), VD->getType()); 2764 assert(Val && "failed to emit constant expression"); 2765 2766 Address Addr = Address::invalid(); 2767 if (!VD->getType()->isReferenceType()) { 2768 // Spill the constant value to a global. 2769 Addr = CGM.createUnnamedGlobalFrom(*VD, Val, 2770 getContext().getDeclAlign(VD)); 2771 llvm::Type *VarTy = getTypes().ConvertTypeForMem(VD->getType()); 2772 auto *PTy = llvm::PointerType::get( 2773 VarTy, getTypes().getTargetAddressSpace(VD->getType())); 2774 Addr = Builder.CreatePointerBitCastOrAddrSpaceCast(Addr, PTy, VarTy); 2775 } else { 2776 // Should we be using the alignment of the constant pointer we emitted? 2777 CharUnits Alignment = 2778 CGM.getNaturalTypeAlignment(E->getType(), 2779 /* BaseInfo= */ nullptr, 2780 /* TBAAInfo= */ nullptr, 2781 /* forPointeeType= */ true); 2782 Addr = Address(Val, ConvertTypeForMem(E->getType()), Alignment); 2783 } 2784 return MakeAddrLValue(Addr, T, AlignmentSource::Decl); 2785 } 2786 2787 // FIXME: Handle other kinds of non-odr-use DeclRefExprs. 2788 2789 // Check for captured variables. 2790 if (E->refersToEnclosingVariableOrCapture()) { 2791 VD = VD->getCanonicalDecl(); 2792 if (auto *FD = LambdaCaptureFields.lookup(VD)) 2793 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue); 2794 if (CapturedStmtInfo) { 2795 auto I = LocalDeclMap.find(VD); 2796 if (I != LocalDeclMap.end()) { 2797 LValue CapLVal; 2798 if (VD->getType()->isReferenceType()) 2799 CapLVal = EmitLoadOfReferenceLValue(I->second, VD->getType(), 2800 AlignmentSource::Decl); 2801 else 2802 CapLVal = MakeAddrLValue(I->second, T); 2803 // Mark lvalue as nontemporal if the variable is marked as nontemporal 2804 // in simd context. 2805 if (getLangOpts().OpenMP && 2806 CGM.getOpenMPRuntime().isNontemporalDecl(VD)) 2807 CapLVal.setNontemporal(/*Value=*/true); 2808 return CapLVal; 2809 } 2810 LValue CapLVal = 2811 EmitCapturedFieldLValue(*this, CapturedStmtInfo->lookup(VD), 2812 CapturedStmtInfo->getContextValue()); 2813 Address LValueAddress = CapLVal.getAddress(*this); 2814 CapLVal = MakeAddrLValue( 2815 Address(LValueAddress.getPointer(), LValueAddress.getElementType(), 2816 getContext().getDeclAlign(VD)), 2817 CapLVal.getType(), LValueBaseInfo(AlignmentSource::Decl), 2818 CapLVal.getTBAAInfo()); 2819 // Mark lvalue as nontemporal if the variable is marked as nontemporal 2820 // in simd context. 2821 if (getLangOpts().OpenMP && 2822 CGM.getOpenMPRuntime().isNontemporalDecl(VD)) 2823 CapLVal.setNontemporal(/*Value=*/true); 2824 return CapLVal; 2825 } 2826 2827 assert(isa<BlockDecl>(CurCodeDecl)); 2828 Address addr = GetAddrOfBlockDecl(VD); 2829 return MakeAddrLValue(addr, T, AlignmentSource::Decl); 2830 } 2831 } 2832 2833 // FIXME: We should be able to assert this for FunctionDecls as well! 2834 // FIXME: We should be able to assert this for all DeclRefExprs, not just 2835 // those with a valid source location. 2836 assert((ND->isUsed(false) || !isa<VarDecl>(ND) || E->isNonOdrUse() || 2837 !E->getLocation().isValid()) && 2838 "Should not use decl without marking it used!"); 2839 2840 if (ND->hasAttr<WeakRefAttr>()) { 2841 const auto *VD = cast<ValueDecl>(ND); 2842 ConstantAddress Aliasee = CGM.GetWeakRefReference(VD); 2843 return MakeAddrLValue(Aliasee, T, AlignmentSource::Decl); 2844 } 2845 2846 if (const auto *VD = dyn_cast<VarDecl>(ND)) { 2847 // Check if this is a global variable. 2848 if (VD->hasLinkage() || VD->isStaticDataMember()) 2849 return EmitGlobalVarDeclLValue(*this, E, VD); 2850 2851 Address addr = Address::invalid(); 2852 2853 // The variable should generally be present in the local decl map. 2854 auto iter = LocalDeclMap.find(VD); 2855 if (iter != LocalDeclMap.end()) { 2856 addr = iter->second; 2857 2858 // Otherwise, it might be static local we haven't emitted yet for 2859 // some reason; most likely, because it's in an outer function. 2860 } else if (VD->isStaticLocal()) { 2861 llvm::Constant *var = CGM.getOrCreateStaticVarDecl( 2862 *VD, CGM.getLLVMLinkageVarDefinition(VD, /*IsConstant=*/false)); 2863 addr = Address( 2864 var, ConvertTypeForMem(VD->getType()), getContext().getDeclAlign(VD)); 2865 2866 // No other cases for now. 2867 } else { 2868 llvm_unreachable("DeclRefExpr for Decl not entered in LocalDeclMap?"); 2869 } 2870 2871 // Handle threadlocal function locals. 2872 if (VD->getTLSKind() != VarDecl::TLS_None) 2873 addr = addr.withPointer( 2874 Builder.CreateThreadLocalAddress(addr.getPointer()), NotKnownNonNull); 2875 2876 // Check for OpenMP threadprivate variables. 2877 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd && 2878 VD->hasAttr<OMPThreadPrivateDeclAttr>()) { 2879 return EmitThreadPrivateVarDeclLValue( 2880 *this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()), 2881 E->getExprLoc()); 2882 } 2883 2884 // Drill into block byref variables. 2885 bool isBlockByref = VD->isEscapingByref(); 2886 if (isBlockByref) { 2887 addr = emitBlockByrefAddress(addr, VD); 2888 } 2889 2890 // Drill into reference types. 2891 LValue LV = VD->getType()->isReferenceType() ? 2892 EmitLoadOfReferenceLValue(addr, VD->getType(), AlignmentSource::Decl) : 2893 MakeAddrLValue(addr, T, AlignmentSource::Decl); 2894 2895 bool isLocalStorage = VD->hasLocalStorage(); 2896 2897 bool NonGCable = isLocalStorage && 2898 !VD->getType()->isReferenceType() && 2899 !isBlockByref; 2900 if (NonGCable) { 2901 LV.getQuals().removeObjCGCAttr(); 2902 LV.setNonGC(true); 2903 } 2904 2905 bool isImpreciseLifetime = 2906 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>()); 2907 if (isImpreciseLifetime) 2908 LV.setARCPreciseLifetime(ARCImpreciseLifetime); 2909 setObjCGCLValueClass(getContext(), E, LV); 2910 return LV; 2911 } 2912 2913 if (const auto *FD = dyn_cast<FunctionDecl>(ND)) { 2914 LValue LV = EmitFunctionDeclLValue(*this, E, FD); 2915 2916 // Emit debuginfo for the function declaration if the target wants to. 2917 if (getContext().getTargetInfo().allowDebugInfoForExternalRef()) { 2918 if (CGDebugInfo *DI = CGM.getModuleDebugInfo()) { 2919 auto *Fn = 2920 cast<llvm::Function>(LV.getPointer(*this)->stripPointerCasts()); 2921 if (!Fn->getSubprogram()) 2922 DI->EmitFunctionDecl(FD, FD->getLocation(), T, Fn); 2923 } 2924 } 2925 2926 return LV; 2927 } 2928 2929 // FIXME: While we're emitting a binding from an enclosing scope, all other 2930 // DeclRefExprs we see should be implicitly treated as if they also refer to 2931 // an enclosing scope. 2932 if (const auto *BD = dyn_cast<BindingDecl>(ND)) { 2933 if (E->refersToEnclosingVariableOrCapture()) { 2934 auto *FD = LambdaCaptureFields.lookup(BD); 2935 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue); 2936 } 2937 return EmitLValue(BD->getBinding()); 2938 } 2939 2940 // We can form DeclRefExprs naming GUID declarations when reconstituting 2941 // non-type template parameters into expressions. 2942 if (const auto *GD = dyn_cast<MSGuidDecl>(ND)) 2943 return MakeAddrLValue(CGM.GetAddrOfMSGuidDecl(GD), T, 2944 AlignmentSource::Decl); 2945 2946 if (const auto *TPO = dyn_cast<TemplateParamObjectDecl>(ND)) 2947 return MakeAddrLValue(CGM.GetAddrOfTemplateParamObject(TPO), T, 2948 AlignmentSource::Decl); 2949 2950 llvm_unreachable("Unhandled DeclRefExpr"); 2951 } 2952 2953 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) { 2954 // __extension__ doesn't affect lvalue-ness. 2955 if (E->getOpcode() == UO_Extension) 2956 return EmitLValue(E->getSubExpr()); 2957 2958 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType()); 2959 switch (E->getOpcode()) { 2960 default: llvm_unreachable("Unknown unary operator lvalue!"); 2961 case UO_Deref: { 2962 QualType T = E->getSubExpr()->getType()->getPointeeType(); 2963 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type"); 2964 2965 LValueBaseInfo BaseInfo; 2966 TBAAAccessInfo TBAAInfo; 2967 Address Addr = EmitPointerWithAlignment(E->getSubExpr(), &BaseInfo, 2968 &TBAAInfo); 2969 LValue LV = MakeAddrLValue(Addr, T, BaseInfo, TBAAInfo); 2970 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace()); 2971 2972 // We should not generate __weak write barrier on indirect reference 2973 // of a pointer to object; as in void foo (__weak id *param); *param = 0; 2974 // But, we continue to generate __strong write barrier on indirect write 2975 // into a pointer to object. 2976 if (getLangOpts().ObjC && 2977 getLangOpts().getGC() != LangOptions::NonGC && 2978 LV.isObjCWeak()) 2979 LV.setNonGC(!E->isOBJCGCCandidate(getContext())); 2980 return LV; 2981 } 2982 case UO_Real: 2983 case UO_Imag: { 2984 LValue LV = EmitLValue(E->getSubExpr()); 2985 assert(LV.isSimple() && "real/imag on non-ordinary l-value"); 2986 2987 // __real is valid on scalars. This is a faster way of testing that. 2988 // __imag can only produce an rvalue on scalars. 2989 if (E->getOpcode() == UO_Real && 2990 !LV.getAddress(*this).getElementType()->isStructTy()) { 2991 assert(E->getSubExpr()->getType()->isArithmeticType()); 2992 return LV; 2993 } 2994 2995 QualType T = ExprTy->castAs<ComplexType>()->getElementType(); 2996 2997 Address Component = 2998 (E->getOpcode() == UO_Real 2999 ? emitAddrOfRealComponent(LV.getAddress(*this), LV.getType()) 3000 : emitAddrOfImagComponent(LV.getAddress(*this), LV.getType())); 3001 LValue ElemLV = MakeAddrLValue(Component, T, LV.getBaseInfo(), 3002 CGM.getTBAAInfoForSubobject(LV, T)); 3003 ElemLV.getQuals().addQualifiers(LV.getQuals()); 3004 return ElemLV; 3005 } 3006 case UO_PreInc: 3007 case UO_PreDec: { 3008 LValue LV = EmitLValue(E->getSubExpr()); 3009 bool isInc = E->getOpcode() == UO_PreInc; 3010 3011 if (E->getType()->isAnyComplexType()) 3012 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/); 3013 else 3014 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/); 3015 return LV; 3016 } 3017 } 3018 } 3019 3020 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) { 3021 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E), 3022 E->getType(), AlignmentSource::Decl); 3023 } 3024 3025 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) { 3026 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E), 3027 E->getType(), AlignmentSource::Decl); 3028 } 3029 3030 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) { 3031 auto SL = E->getFunctionName(); 3032 assert(SL != nullptr && "No StringLiteral name in PredefinedExpr"); 3033 StringRef FnName = CurFn->getName(); 3034 if (FnName.startswith("\01")) 3035 FnName = FnName.substr(1); 3036 StringRef NameItems[] = { 3037 PredefinedExpr::getIdentKindName(E->getIdentKind()), FnName}; 3038 std::string GVName = llvm::join(NameItems, NameItems + 2, "."); 3039 if (auto *BD = dyn_cast_or_null<BlockDecl>(CurCodeDecl)) { 3040 std::string Name = std::string(SL->getString()); 3041 if (!Name.empty()) { 3042 unsigned Discriminator = 3043 CGM.getCXXABI().getMangleContext().getBlockId(BD, true); 3044 if (Discriminator) 3045 Name += "_" + Twine(Discriminator + 1).str(); 3046 auto C = CGM.GetAddrOfConstantCString(Name, GVName.c_str()); 3047 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl); 3048 } else { 3049 auto C = 3050 CGM.GetAddrOfConstantCString(std::string(FnName), GVName.c_str()); 3051 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl); 3052 } 3053 } 3054 auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName); 3055 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl); 3056 } 3057 3058 /// Emit a type description suitable for use by a runtime sanitizer library. The 3059 /// format of a type descriptor is 3060 /// 3061 /// \code 3062 /// { i16 TypeKind, i16 TypeInfo } 3063 /// \endcode 3064 /// 3065 /// followed by an array of i8 containing the type name. TypeKind is 0 for an 3066 /// integer, 1 for a floating point value, and -1 for anything else. 3067 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) { 3068 // Only emit each type's descriptor once. 3069 if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T)) 3070 return C; 3071 3072 uint16_t TypeKind = -1; 3073 uint16_t TypeInfo = 0; 3074 3075 if (T->isIntegerType()) { 3076 TypeKind = 0; 3077 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) | 3078 (T->isSignedIntegerType() ? 1 : 0); 3079 } else if (T->isFloatingType()) { 3080 TypeKind = 1; 3081 TypeInfo = getContext().getTypeSize(T); 3082 } 3083 3084 // Format the type name as if for a diagnostic, including quotes and 3085 // optionally an 'aka'. 3086 SmallString<32> Buffer; 3087 CGM.getDiags().ConvertArgToString( 3088 DiagnosticsEngine::ak_qualtype, (intptr_t)T.getAsOpaquePtr(), StringRef(), 3089 StringRef(), std::nullopt, Buffer, std::nullopt); 3090 3091 llvm::Constant *Components[] = { 3092 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo), 3093 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer) 3094 }; 3095 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components); 3096 3097 auto *GV = new llvm::GlobalVariable( 3098 CGM.getModule(), Descriptor->getType(), 3099 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor); 3100 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3101 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(GV); 3102 3103 // Remember the descriptor for this type. 3104 CGM.setTypeDescriptorInMap(T, GV); 3105 3106 return GV; 3107 } 3108 3109 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) { 3110 llvm::Type *TargetTy = IntPtrTy; 3111 3112 if (V->getType() == TargetTy) 3113 return V; 3114 3115 // Floating-point types which fit into intptr_t are bitcast to integers 3116 // and then passed directly (after zero-extension, if necessary). 3117 if (V->getType()->isFloatingPointTy()) { 3118 unsigned Bits = V->getType()->getPrimitiveSizeInBits().getFixedValue(); 3119 if (Bits <= TargetTy->getIntegerBitWidth()) 3120 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(), 3121 Bits)); 3122 } 3123 3124 // Integers which fit in intptr_t are zero-extended and passed directly. 3125 if (V->getType()->isIntegerTy() && 3126 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth()) 3127 return Builder.CreateZExt(V, TargetTy); 3128 3129 // Pointers are passed directly, everything else is passed by address. 3130 if (!V->getType()->isPointerTy()) { 3131 Address Ptr = CreateDefaultAlignTempAlloca(V->getType()); 3132 Builder.CreateStore(V, Ptr); 3133 V = Ptr.getPointer(); 3134 } 3135 return Builder.CreatePtrToInt(V, TargetTy); 3136 } 3137 3138 /// Emit a representation of a SourceLocation for passing to a handler 3139 /// in a sanitizer runtime library. The format for this data is: 3140 /// \code 3141 /// struct SourceLocation { 3142 /// const char *Filename; 3143 /// int32_t Line, Column; 3144 /// }; 3145 /// \endcode 3146 /// For an invalid SourceLocation, the Filename pointer is null. 3147 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) { 3148 llvm::Constant *Filename; 3149 int Line, Column; 3150 3151 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc); 3152 if (PLoc.isValid()) { 3153 StringRef FilenameString = PLoc.getFilename(); 3154 3155 int PathComponentsToStrip = 3156 CGM.getCodeGenOpts().EmitCheckPathComponentsToStrip; 3157 if (PathComponentsToStrip < 0) { 3158 assert(PathComponentsToStrip != INT_MIN); 3159 int PathComponentsToKeep = -PathComponentsToStrip; 3160 auto I = llvm::sys::path::rbegin(FilenameString); 3161 auto E = llvm::sys::path::rend(FilenameString); 3162 while (I != E && --PathComponentsToKeep) 3163 ++I; 3164 3165 FilenameString = FilenameString.substr(I - E); 3166 } else if (PathComponentsToStrip > 0) { 3167 auto I = llvm::sys::path::begin(FilenameString); 3168 auto E = llvm::sys::path::end(FilenameString); 3169 while (I != E && PathComponentsToStrip--) 3170 ++I; 3171 3172 if (I != E) 3173 FilenameString = 3174 FilenameString.substr(I - llvm::sys::path::begin(FilenameString)); 3175 else 3176 FilenameString = llvm::sys::path::filename(FilenameString); 3177 } 3178 3179 auto FilenameGV = 3180 CGM.GetAddrOfConstantCString(std::string(FilenameString), ".src"); 3181 CGM.getSanitizerMetadata()->disableSanitizerForGlobal( 3182 cast<llvm::GlobalVariable>( 3183 FilenameGV.getPointer()->stripPointerCasts())); 3184 Filename = FilenameGV.getPointer(); 3185 Line = PLoc.getLine(); 3186 Column = PLoc.getColumn(); 3187 } else { 3188 Filename = llvm::Constant::getNullValue(Int8PtrTy); 3189 Line = Column = 0; 3190 } 3191 3192 llvm::Constant *Data[] = {Filename, Builder.getInt32(Line), 3193 Builder.getInt32(Column)}; 3194 3195 return llvm::ConstantStruct::getAnon(Data); 3196 } 3197 3198 namespace { 3199 /// Specify under what conditions this check can be recovered 3200 enum class CheckRecoverableKind { 3201 /// Always terminate program execution if this check fails. 3202 Unrecoverable, 3203 /// Check supports recovering, runtime has both fatal (noreturn) and 3204 /// non-fatal handlers for this check. 3205 Recoverable, 3206 /// Runtime conditionally aborts, always need to support recovery. 3207 AlwaysRecoverable 3208 }; 3209 } 3210 3211 static CheckRecoverableKind getRecoverableKind(SanitizerMask Kind) { 3212 assert(Kind.countPopulation() == 1); 3213 if (Kind == SanitizerKind::Vptr) 3214 return CheckRecoverableKind::AlwaysRecoverable; 3215 else if (Kind == SanitizerKind::Return || Kind == SanitizerKind::Unreachable) 3216 return CheckRecoverableKind::Unrecoverable; 3217 else 3218 return CheckRecoverableKind::Recoverable; 3219 } 3220 3221 namespace { 3222 struct SanitizerHandlerInfo { 3223 char const *const Name; 3224 unsigned Version; 3225 }; 3226 } 3227 3228 const SanitizerHandlerInfo SanitizerHandlers[] = { 3229 #define SANITIZER_CHECK(Enum, Name, Version) {#Name, Version}, 3230 LIST_SANITIZER_CHECKS 3231 #undef SANITIZER_CHECK 3232 }; 3233 3234 static void emitCheckHandlerCall(CodeGenFunction &CGF, 3235 llvm::FunctionType *FnType, 3236 ArrayRef<llvm::Value *> FnArgs, 3237 SanitizerHandler CheckHandler, 3238 CheckRecoverableKind RecoverKind, bool IsFatal, 3239 llvm::BasicBlock *ContBB) { 3240 assert(IsFatal || RecoverKind != CheckRecoverableKind::Unrecoverable); 3241 std::optional<ApplyDebugLocation> DL; 3242 if (!CGF.Builder.getCurrentDebugLocation()) { 3243 // Ensure that the call has at least an artificial debug location. 3244 DL.emplace(CGF, SourceLocation()); 3245 } 3246 bool NeedsAbortSuffix = 3247 IsFatal && RecoverKind != CheckRecoverableKind::Unrecoverable; 3248 bool MinimalRuntime = CGF.CGM.getCodeGenOpts().SanitizeMinimalRuntime; 3249 const SanitizerHandlerInfo &CheckInfo = SanitizerHandlers[CheckHandler]; 3250 const StringRef CheckName = CheckInfo.Name; 3251 std::string FnName = "__ubsan_handle_" + CheckName.str(); 3252 if (CheckInfo.Version && !MinimalRuntime) 3253 FnName += "_v" + llvm::utostr(CheckInfo.Version); 3254 if (MinimalRuntime) 3255 FnName += "_minimal"; 3256 if (NeedsAbortSuffix) 3257 FnName += "_abort"; 3258 bool MayReturn = 3259 !IsFatal || RecoverKind == CheckRecoverableKind::AlwaysRecoverable; 3260 3261 llvm::AttrBuilder B(CGF.getLLVMContext()); 3262 if (!MayReturn) { 3263 B.addAttribute(llvm::Attribute::NoReturn) 3264 .addAttribute(llvm::Attribute::NoUnwind); 3265 } 3266 B.addUWTableAttr(llvm::UWTableKind::Default); 3267 3268 llvm::FunctionCallee Fn = CGF.CGM.CreateRuntimeFunction( 3269 FnType, FnName, 3270 llvm::AttributeList::get(CGF.getLLVMContext(), 3271 llvm::AttributeList::FunctionIndex, B), 3272 /*Local=*/true); 3273 llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs); 3274 if (!MayReturn) { 3275 HandlerCall->setDoesNotReturn(); 3276 CGF.Builder.CreateUnreachable(); 3277 } else { 3278 CGF.Builder.CreateBr(ContBB); 3279 } 3280 } 3281 3282 void CodeGenFunction::EmitCheck( 3283 ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked, 3284 SanitizerHandler CheckHandler, ArrayRef<llvm::Constant *> StaticArgs, 3285 ArrayRef<llvm::Value *> DynamicArgs) { 3286 assert(IsSanitizerScope); 3287 assert(Checked.size() > 0); 3288 assert(CheckHandler >= 0 && 3289 size_t(CheckHandler) < std::size(SanitizerHandlers)); 3290 const StringRef CheckName = SanitizerHandlers[CheckHandler].Name; 3291 3292 llvm::Value *FatalCond = nullptr; 3293 llvm::Value *RecoverableCond = nullptr; 3294 llvm::Value *TrapCond = nullptr; 3295 for (int i = 0, n = Checked.size(); i < n; ++i) { 3296 llvm::Value *Check = Checked[i].first; 3297 // -fsanitize-trap= overrides -fsanitize-recover=. 3298 llvm::Value *&Cond = 3299 CGM.getCodeGenOpts().SanitizeTrap.has(Checked[i].second) 3300 ? TrapCond 3301 : CGM.getCodeGenOpts().SanitizeRecover.has(Checked[i].second) 3302 ? RecoverableCond 3303 : FatalCond; 3304 Cond = Cond ? Builder.CreateAnd(Cond, Check) : Check; 3305 } 3306 3307 if (TrapCond) 3308 EmitTrapCheck(TrapCond, CheckHandler); 3309 if (!FatalCond && !RecoverableCond) 3310 return; 3311 3312 llvm::Value *JointCond; 3313 if (FatalCond && RecoverableCond) 3314 JointCond = Builder.CreateAnd(FatalCond, RecoverableCond); 3315 else 3316 JointCond = FatalCond ? FatalCond : RecoverableCond; 3317 assert(JointCond); 3318 3319 CheckRecoverableKind RecoverKind = getRecoverableKind(Checked[0].second); 3320 assert(SanOpts.has(Checked[0].second)); 3321 #ifndef NDEBUG 3322 for (int i = 1, n = Checked.size(); i < n; ++i) { 3323 assert(RecoverKind == getRecoverableKind(Checked[i].second) && 3324 "All recoverable kinds in a single check must be same!"); 3325 assert(SanOpts.has(Checked[i].second)); 3326 } 3327 #endif 3328 3329 llvm::BasicBlock *Cont = createBasicBlock("cont"); 3330 llvm::BasicBlock *Handlers = createBasicBlock("handler." + CheckName); 3331 llvm::Instruction *Branch = Builder.CreateCondBr(JointCond, Cont, Handlers); 3332 // Give hint that we very much don't expect to execute the handler 3333 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp 3334 llvm::MDBuilder MDHelper(getLLVMContext()); 3335 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1); 3336 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node); 3337 EmitBlock(Handlers); 3338 3339 // Handler functions take an i8* pointing to the (handler-specific) static 3340 // information block, followed by a sequence of intptr_t arguments 3341 // representing operand values. 3342 SmallVector<llvm::Value *, 4> Args; 3343 SmallVector<llvm::Type *, 4> ArgTypes; 3344 if (!CGM.getCodeGenOpts().SanitizeMinimalRuntime) { 3345 Args.reserve(DynamicArgs.size() + 1); 3346 ArgTypes.reserve(DynamicArgs.size() + 1); 3347 3348 // Emit handler arguments and create handler function type. 3349 if (!StaticArgs.empty()) { 3350 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs); 3351 auto *InfoPtr = new llvm::GlobalVariable( 3352 CGM.getModule(), Info->getType(), false, 3353 llvm::GlobalVariable::PrivateLinkage, Info, "", nullptr, 3354 llvm::GlobalVariable::NotThreadLocal, 3355 CGM.getDataLayout().getDefaultGlobalsAddressSpace()); 3356 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3357 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr); 3358 Args.push_back(InfoPtr); 3359 ArgTypes.push_back(Args.back()->getType()); 3360 } 3361 3362 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) { 3363 Args.push_back(EmitCheckValue(DynamicArgs[i])); 3364 ArgTypes.push_back(IntPtrTy); 3365 } 3366 } 3367 3368 llvm::FunctionType *FnType = 3369 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false); 3370 3371 if (!FatalCond || !RecoverableCond) { 3372 // Simple case: we need to generate a single handler call, either 3373 // fatal, or non-fatal. 3374 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, 3375 (FatalCond != nullptr), Cont); 3376 } else { 3377 // Emit two handler calls: first one for set of unrecoverable checks, 3378 // another one for recoverable. 3379 llvm::BasicBlock *NonFatalHandlerBB = 3380 createBasicBlock("non_fatal." + CheckName); 3381 llvm::BasicBlock *FatalHandlerBB = createBasicBlock("fatal." + CheckName); 3382 Builder.CreateCondBr(FatalCond, NonFatalHandlerBB, FatalHandlerBB); 3383 EmitBlock(FatalHandlerBB); 3384 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, true, 3385 NonFatalHandlerBB); 3386 EmitBlock(NonFatalHandlerBB); 3387 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, false, 3388 Cont); 3389 } 3390 3391 EmitBlock(Cont); 3392 } 3393 3394 void CodeGenFunction::EmitCfiSlowPathCheck( 3395 SanitizerMask Kind, llvm::Value *Cond, llvm::ConstantInt *TypeId, 3396 llvm::Value *Ptr, ArrayRef<llvm::Constant *> StaticArgs) { 3397 llvm::BasicBlock *Cont = createBasicBlock("cfi.cont"); 3398 3399 llvm::BasicBlock *CheckBB = createBasicBlock("cfi.slowpath"); 3400 llvm::BranchInst *BI = Builder.CreateCondBr(Cond, Cont, CheckBB); 3401 3402 llvm::MDBuilder MDHelper(getLLVMContext()); 3403 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1); 3404 BI->setMetadata(llvm::LLVMContext::MD_prof, Node); 3405 3406 EmitBlock(CheckBB); 3407 3408 bool WithDiag = !CGM.getCodeGenOpts().SanitizeTrap.has(Kind); 3409 3410 llvm::CallInst *CheckCall; 3411 llvm::FunctionCallee SlowPathFn; 3412 if (WithDiag) { 3413 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs); 3414 auto *InfoPtr = 3415 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false, 3416 llvm::GlobalVariable::PrivateLinkage, Info); 3417 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3418 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr); 3419 3420 SlowPathFn = CGM.getModule().getOrInsertFunction( 3421 "__cfi_slowpath_diag", 3422 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, 3423 false)); 3424 CheckCall = Builder.CreateCall( 3425 SlowPathFn, {TypeId, Ptr, Builder.CreateBitCast(InfoPtr, Int8PtrTy)}); 3426 } else { 3427 SlowPathFn = CGM.getModule().getOrInsertFunction( 3428 "__cfi_slowpath", 3429 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy}, false)); 3430 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr}); 3431 } 3432 3433 CGM.setDSOLocal( 3434 cast<llvm::GlobalValue>(SlowPathFn.getCallee()->stripPointerCasts())); 3435 CheckCall->setDoesNotThrow(); 3436 3437 EmitBlock(Cont); 3438 } 3439 3440 // Emit a stub for __cfi_check function so that the linker knows about this 3441 // symbol in LTO mode. 3442 void CodeGenFunction::EmitCfiCheckStub() { 3443 llvm::Module *M = &CGM.getModule(); 3444 auto &Ctx = M->getContext(); 3445 llvm::Function *F = llvm::Function::Create( 3446 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, false), 3447 llvm::GlobalValue::WeakAnyLinkage, "__cfi_check", M); 3448 CGM.setDSOLocal(F); 3449 llvm::BasicBlock *BB = llvm::BasicBlock::Create(Ctx, "entry", F); 3450 // FIXME: consider emitting an intrinsic call like 3451 // call void @llvm.cfi_check(i64 %0, i8* %1, i8* %2) 3452 // which can be lowered in CrossDSOCFI pass to the actual contents of 3453 // __cfi_check. This would allow inlining of __cfi_check calls. 3454 llvm::CallInst::Create( 3455 llvm::Intrinsic::getDeclaration(M, llvm::Intrinsic::trap), "", BB); 3456 llvm::ReturnInst::Create(Ctx, nullptr, BB); 3457 } 3458 3459 // This function is basically a switch over the CFI failure kind, which is 3460 // extracted from CFICheckFailData (1st function argument). Each case is either 3461 // llvm.trap or a call to one of the two runtime handlers, based on 3462 // -fsanitize-trap and -fsanitize-recover settings. Default case (invalid 3463 // failure kind) traps, but this should really never happen. CFICheckFailData 3464 // can be nullptr if the calling module has -fsanitize-trap behavior for this 3465 // check kind; in this case __cfi_check_fail traps as well. 3466 void CodeGenFunction::EmitCfiCheckFail() { 3467 SanitizerScope SanScope(this); 3468 FunctionArgList Args; 3469 ImplicitParamDecl ArgData(getContext(), getContext().VoidPtrTy, 3470 ImplicitParamDecl::Other); 3471 ImplicitParamDecl ArgAddr(getContext(), getContext().VoidPtrTy, 3472 ImplicitParamDecl::Other); 3473 Args.push_back(&ArgData); 3474 Args.push_back(&ArgAddr); 3475 3476 const CGFunctionInfo &FI = 3477 CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, Args); 3478 3479 llvm::Function *F = llvm::Function::Create( 3480 llvm::FunctionType::get(VoidTy, {VoidPtrTy, VoidPtrTy}, false), 3481 llvm::GlobalValue::WeakODRLinkage, "__cfi_check_fail", &CGM.getModule()); 3482 3483 CGM.SetLLVMFunctionAttributes(GlobalDecl(), FI, F, /*IsThunk=*/false); 3484 CGM.SetLLVMFunctionAttributesForDefinition(nullptr, F); 3485 F->setVisibility(llvm::GlobalValue::HiddenVisibility); 3486 3487 StartFunction(GlobalDecl(), CGM.getContext().VoidTy, F, FI, Args, 3488 SourceLocation()); 3489 3490 // This function is not affected by NoSanitizeList. This function does 3491 // not have a source location, but "src:*" would still apply. Revert any 3492 // changes to SanOpts made in StartFunction. 3493 SanOpts = CGM.getLangOpts().Sanitize; 3494 3495 llvm::Value *Data = 3496 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgData), /*Volatile=*/false, 3497 CGM.getContext().VoidPtrTy, ArgData.getLocation()); 3498 llvm::Value *Addr = 3499 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgAddr), /*Volatile=*/false, 3500 CGM.getContext().VoidPtrTy, ArgAddr.getLocation()); 3501 3502 // Data == nullptr means the calling module has trap behaviour for this check. 3503 llvm::Value *DataIsNotNullPtr = 3504 Builder.CreateICmpNE(Data, llvm::ConstantPointerNull::get(Int8PtrTy)); 3505 EmitTrapCheck(DataIsNotNullPtr, SanitizerHandler::CFICheckFail); 3506 3507 llvm::StructType *SourceLocationTy = 3508 llvm::StructType::get(VoidPtrTy, Int32Ty, Int32Ty); 3509 llvm::StructType *CfiCheckFailDataTy = 3510 llvm::StructType::get(Int8Ty, SourceLocationTy, VoidPtrTy); 3511 3512 llvm::Value *V = Builder.CreateConstGEP2_32( 3513 CfiCheckFailDataTy, 3514 Builder.CreatePointerCast(Data, CfiCheckFailDataTy->getPointerTo(0)), 0, 3515 0); 3516 3517 Address CheckKindAddr(V, Int8Ty, getIntAlign()); 3518 llvm::Value *CheckKind = Builder.CreateLoad(CheckKindAddr); 3519 3520 llvm::Value *AllVtables = llvm::MetadataAsValue::get( 3521 CGM.getLLVMContext(), 3522 llvm::MDString::get(CGM.getLLVMContext(), "all-vtables")); 3523 llvm::Value *ValidVtable = Builder.CreateZExt( 3524 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::type_test), 3525 {Addr, AllVtables}), 3526 IntPtrTy); 3527 3528 const std::pair<int, SanitizerMask> CheckKinds[] = { 3529 {CFITCK_VCall, SanitizerKind::CFIVCall}, 3530 {CFITCK_NVCall, SanitizerKind::CFINVCall}, 3531 {CFITCK_DerivedCast, SanitizerKind::CFIDerivedCast}, 3532 {CFITCK_UnrelatedCast, SanitizerKind::CFIUnrelatedCast}, 3533 {CFITCK_ICall, SanitizerKind::CFIICall}}; 3534 3535 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 5> Checks; 3536 for (auto CheckKindMaskPair : CheckKinds) { 3537 int Kind = CheckKindMaskPair.first; 3538 SanitizerMask Mask = CheckKindMaskPair.second; 3539 llvm::Value *Cond = 3540 Builder.CreateICmpNE(CheckKind, llvm::ConstantInt::get(Int8Ty, Kind)); 3541 if (CGM.getLangOpts().Sanitize.has(Mask)) 3542 EmitCheck(std::make_pair(Cond, Mask), SanitizerHandler::CFICheckFail, {}, 3543 {Data, Addr, ValidVtable}); 3544 else 3545 EmitTrapCheck(Cond, SanitizerHandler::CFICheckFail); 3546 } 3547 3548 FinishFunction(); 3549 // The only reference to this function will be created during LTO link. 3550 // Make sure it survives until then. 3551 CGM.addUsedGlobal(F); 3552 } 3553 3554 void CodeGenFunction::EmitUnreachable(SourceLocation Loc) { 3555 if (SanOpts.has(SanitizerKind::Unreachable)) { 3556 SanitizerScope SanScope(this); 3557 EmitCheck(std::make_pair(static_cast<llvm::Value *>(Builder.getFalse()), 3558 SanitizerKind::Unreachable), 3559 SanitizerHandler::BuiltinUnreachable, 3560 EmitCheckSourceLocation(Loc), std::nullopt); 3561 } 3562 Builder.CreateUnreachable(); 3563 } 3564 3565 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked, 3566 SanitizerHandler CheckHandlerID) { 3567 llvm::BasicBlock *Cont = createBasicBlock("cont"); 3568 3569 // If we're optimizing, collapse all calls to trap down to just one per 3570 // check-type per function to save on code size. 3571 if (TrapBBs.size() <= CheckHandlerID) 3572 TrapBBs.resize(CheckHandlerID + 1); 3573 llvm::BasicBlock *&TrapBB = TrapBBs[CheckHandlerID]; 3574 3575 if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB || 3576 (CurCodeDecl && CurCodeDecl->hasAttr<OptimizeNoneAttr>())) { 3577 TrapBB = createBasicBlock("trap"); 3578 Builder.CreateCondBr(Checked, Cont, TrapBB); 3579 EmitBlock(TrapBB); 3580 3581 llvm::CallInst *TrapCall = 3582 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::ubsantrap), 3583 llvm::ConstantInt::get(CGM.Int8Ty, CheckHandlerID)); 3584 3585 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) { 3586 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name", 3587 CGM.getCodeGenOpts().TrapFuncName); 3588 TrapCall->addFnAttr(A); 3589 } 3590 TrapCall->setDoesNotReturn(); 3591 TrapCall->setDoesNotThrow(); 3592 Builder.CreateUnreachable(); 3593 } else { 3594 auto Call = TrapBB->begin(); 3595 assert(isa<llvm::CallInst>(Call) && "Expected call in trap BB"); 3596 3597 Call->applyMergedLocation(Call->getDebugLoc(), 3598 Builder.getCurrentDebugLocation()); 3599 Builder.CreateCondBr(Checked, Cont, TrapBB); 3600 } 3601 3602 EmitBlock(Cont); 3603 } 3604 3605 llvm::CallInst *CodeGenFunction::EmitTrapCall(llvm::Intrinsic::ID IntrID) { 3606 llvm::CallInst *TrapCall = 3607 Builder.CreateCall(CGM.getIntrinsic(IntrID)); 3608 3609 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) { 3610 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name", 3611 CGM.getCodeGenOpts().TrapFuncName); 3612 TrapCall->addFnAttr(A); 3613 } 3614 3615 return TrapCall; 3616 } 3617 3618 Address CodeGenFunction::EmitArrayToPointerDecay(const Expr *E, 3619 LValueBaseInfo *BaseInfo, 3620 TBAAAccessInfo *TBAAInfo) { 3621 assert(E->getType()->isArrayType() && 3622 "Array to pointer decay must have array source type!"); 3623 3624 // Expressions of array type can't be bitfields or vector elements. 3625 LValue LV = EmitLValue(E); 3626 Address Addr = LV.getAddress(*this); 3627 3628 // If the array type was an incomplete type, we need to make sure 3629 // the decay ends up being the right type. 3630 llvm::Type *NewTy = ConvertType(E->getType()); 3631 Addr = Addr.withElementType(NewTy); 3632 3633 // Note that VLA pointers are always decayed, so we don't need to do 3634 // anything here. 3635 if (!E->getType()->isVariableArrayType()) { 3636 assert(isa<llvm::ArrayType>(Addr.getElementType()) && 3637 "Expected pointer to array"); 3638 Addr = Builder.CreateConstArrayGEP(Addr, 0, "arraydecay"); 3639 } 3640 3641 // The result of this decay conversion points to an array element within the 3642 // base lvalue. However, since TBAA currently does not support representing 3643 // accesses to elements of member arrays, we conservatively represent accesses 3644 // to the pointee object as if it had no any base lvalue specified. 3645 // TODO: Support TBAA for member arrays. 3646 QualType EltType = E->getType()->castAsArrayTypeUnsafe()->getElementType(); 3647 if (BaseInfo) *BaseInfo = LV.getBaseInfo(); 3648 if (TBAAInfo) *TBAAInfo = CGM.getTBAAAccessInfo(EltType); 3649 3650 return Addr.withElementType(ConvertTypeForMem(EltType)); 3651 } 3652 3653 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an 3654 /// array to pointer, return the array subexpression. 3655 static const Expr *isSimpleArrayDecayOperand(const Expr *E) { 3656 // If this isn't just an array->pointer decay, bail out. 3657 const auto *CE = dyn_cast<CastExpr>(E); 3658 if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay) 3659 return nullptr; 3660 3661 // If this is a decay from variable width array, bail out. 3662 const Expr *SubExpr = CE->getSubExpr(); 3663 if (SubExpr->getType()->isVariableArrayType()) 3664 return nullptr; 3665 3666 return SubExpr; 3667 } 3668 3669 static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF, 3670 llvm::Type *elemType, 3671 llvm::Value *ptr, 3672 ArrayRef<llvm::Value*> indices, 3673 bool inbounds, 3674 bool signedIndices, 3675 SourceLocation loc, 3676 const llvm::Twine &name = "arrayidx") { 3677 if (inbounds) { 3678 return CGF.EmitCheckedInBoundsGEP(elemType, ptr, indices, signedIndices, 3679 CodeGenFunction::NotSubtraction, loc, 3680 name); 3681 } else { 3682 return CGF.Builder.CreateGEP(elemType, ptr, indices, name); 3683 } 3684 } 3685 3686 static CharUnits getArrayElementAlign(CharUnits arrayAlign, 3687 llvm::Value *idx, 3688 CharUnits eltSize) { 3689 // If we have a constant index, we can use the exact offset of the 3690 // element we're accessing. 3691 if (auto constantIdx = dyn_cast<llvm::ConstantInt>(idx)) { 3692 CharUnits offset = constantIdx->getZExtValue() * eltSize; 3693 return arrayAlign.alignmentAtOffset(offset); 3694 3695 // Otherwise, use the worst-case alignment for any element. 3696 } else { 3697 return arrayAlign.alignmentOfArrayElement(eltSize); 3698 } 3699 } 3700 3701 static QualType getFixedSizeElementType(const ASTContext &ctx, 3702 const VariableArrayType *vla) { 3703 QualType eltType; 3704 do { 3705 eltType = vla->getElementType(); 3706 } while ((vla = ctx.getAsVariableArrayType(eltType))); 3707 return eltType; 3708 } 3709 3710 /// Given an array base, check whether its member access belongs to a record 3711 /// with preserve_access_index attribute or not. 3712 static bool IsPreserveAIArrayBase(CodeGenFunction &CGF, const Expr *ArrayBase) { 3713 if (!ArrayBase || !CGF.getDebugInfo()) 3714 return false; 3715 3716 // Only support base as either a MemberExpr or DeclRefExpr. 3717 // DeclRefExpr to cover cases like: 3718 // struct s { int a; int b[10]; }; 3719 // struct s *p; 3720 // p[1].a 3721 // p[1] will generate a DeclRefExpr and p[1].a is a MemberExpr. 3722 // p->b[5] is a MemberExpr example. 3723 const Expr *E = ArrayBase->IgnoreImpCasts(); 3724 if (const auto *ME = dyn_cast<MemberExpr>(E)) 3725 return ME->getMemberDecl()->hasAttr<BPFPreserveAccessIndexAttr>(); 3726 3727 if (const auto *DRE = dyn_cast<DeclRefExpr>(E)) { 3728 const auto *VarDef = dyn_cast<VarDecl>(DRE->getDecl()); 3729 if (!VarDef) 3730 return false; 3731 3732 const auto *PtrT = VarDef->getType()->getAs<PointerType>(); 3733 if (!PtrT) 3734 return false; 3735 3736 const auto *PointeeT = PtrT->getPointeeType() 3737 ->getUnqualifiedDesugaredType(); 3738 if (const auto *RecT = dyn_cast<RecordType>(PointeeT)) 3739 return RecT->getDecl()->hasAttr<BPFPreserveAccessIndexAttr>(); 3740 return false; 3741 } 3742 3743 return false; 3744 } 3745 3746 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr, 3747 ArrayRef<llvm::Value *> indices, 3748 QualType eltType, bool inbounds, 3749 bool signedIndices, SourceLocation loc, 3750 QualType *arrayType = nullptr, 3751 const Expr *Base = nullptr, 3752 const llvm::Twine &name = "arrayidx") { 3753 // All the indices except that last must be zero. 3754 #ifndef NDEBUG 3755 for (auto *idx : indices.drop_back()) 3756 assert(isa<llvm::ConstantInt>(idx) && 3757 cast<llvm::ConstantInt>(idx)->isZero()); 3758 #endif 3759 3760 // Determine the element size of the statically-sized base. This is 3761 // the thing that the indices are expressed in terms of. 3762 if (auto vla = CGF.getContext().getAsVariableArrayType(eltType)) { 3763 eltType = getFixedSizeElementType(CGF.getContext(), vla); 3764 } 3765 3766 // We can use that to compute the best alignment of the element. 3767 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType); 3768 CharUnits eltAlign = 3769 getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize); 3770 3771 llvm::Value *eltPtr; 3772 auto LastIndex = dyn_cast<llvm::ConstantInt>(indices.back()); 3773 if (!LastIndex || 3774 (!CGF.IsInPreservedAIRegion && !IsPreserveAIArrayBase(CGF, Base))) { 3775 eltPtr = emitArraySubscriptGEP( 3776 CGF, addr.getElementType(), addr.getPointer(), indices, inbounds, 3777 signedIndices, loc, name); 3778 } else { 3779 // Remember the original array subscript for bpf target 3780 unsigned idx = LastIndex->getZExtValue(); 3781 llvm::DIType *DbgInfo = nullptr; 3782 if (arrayType) 3783 DbgInfo = CGF.getDebugInfo()->getOrCreateStandaloneType(*arrayType, loc); 3784 eltPtr = CGF.Builder.CreatePreserveArrayAccessIndex(addr.getElementType(), 3785 addr.getPointer(), 3786 indices.size() - 1, 3787 idx, DbgInfo); 3788 } 3789 3790 return Address(eltPtr, CGF.ConvertTypeForMem(eltType), eltAlign); 3791 } 3792 3793 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E, 3794 bool Accessed) { 3795 // The index must always be an integer, which is not an aggregate. Emit it 3796 // in lexical order (this complexity is, sadly, required by C++17). 3797 llvm::Value *IdxPre = 3798 (E->getLHS() == E->getIdx()) ? EmitScalarExpr(E->getIdx()) : nullptr; 3799 bool SignedIndices = false; 3800 auto EmitIdxAfterBase = [&, IdxPre](bool Promote) -> llvm::Value * { 3801 auto *Idx = IdxPre; 3802 if (E->getLHS() != E->getIdx()) { 3803 assert(E->getRHS() == E->getIdx() && "index was neither LHS nor RHS"); 3804 Idx = EmitScalarExpr(E->getIdx()); 3805 } 3806 3807 QualType IdxTy = E->getIdx()->getType(); 3808 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType(); 3809 SignedIndices |= IdxSigned; 3810 3811 if (SanOpts.has(SanitizerKind::ArrayBounds)) 3812 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed); 3813 3814 // Extend or truncate the index type to 32 or 64-bits. 3815 if (Promote && Idx->getType() != IntPtrTy) 3816 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom"); 3817 3818 return Idx; 3819 }; 3820 IdxPre = nullptr; 3821 3822 // If the base is a vector type, then we are forming a vector element lvalue 3823 // with this subscript. 3824 if (E->getBase()->getType()->isVectorType() && 3825 !isa<ExtVectorElementExpr>(E->getBase())) { 3826 // Emit the vector as an lvalue to get its address. 3827 LValue LHS = EmitLValue(E->getBase()); 3828 auto *Idx = EmitIdxAfterBase(/*Promote*/false); 3829 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!"); 3830 return LValue::MakeVectorElt(LHS.getAddress(*this), Idx, 3831 E->getBase()->getType(), LHS.getBaseInfo(), 3832 TBAAAccessInfo()); 3833 } 3834 3835 // All the other cases basically behave like simple offsetting. 3836 3837 // Handle the extvector case we ignored above. 3838 if (isa<ExtVectorElementExpr>(E->getBase())) { 3839 LValue LV = EmitLValue(E->getBase()); 3840 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 3841 Address Addr = EmitExtVectorElementLValue(LV); 3842 3843 QualType EltType = LV.getType()->castAs<VectorType>()->getElementType(); 3844 Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true, 3845 SignedIndices, E->getExprLoc()); 3846 return MakeAddrLValue(Addr, EltType, LV.getBaseInfo(), 3847 CGM.getTBAAInfoForSubobject(LV, EltType)); 3848 } 3849 3850 LValueBaseInfo EltBaseInfo; 3851 TBAAAccessInfo EltTBAAInfo; 3852 Address Addr = Address::invalid(); 3853 if (const VariableArrayType *vla = 3854 getContext().getAsVariableArrayType(E->getType())) { 3855 // The base must be a pointer, which is not an aggregate. Emit 3856 // it. It needs to be emitted first in case it's what captures 3857 // the VLA bounds. 3858 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo); 3859 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 3860 3861 // The element count here is the total number of non-VLA elements. 3862 llvm::Value *numElements = getVLASize(vla).NumElts; 3863 3864 // Effectively, the multiply by the VLA size is part of the GEP. 3865 // GEP indexes are signed, and scaling an index isn't permitted to 3866 // signed-overflow, so we use the same semantics for our explicit 3867 // multiply. We suppress this if overflow is not undefined behavior. 3868 if (getLangOpts().isSignedOverflowDefined()) { 3869 Idx = Builder.CreateMul(Idx, numElements); 3870 } else { 3871 Idx = Builder.CreateNSWMul(Idx, numElements); 3872 } 3873 3874 Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(), 3875 !getLangOpts().isSignedOverflowDefined(), 3876 SignedIndices, E->getExprLoc()); 3877 3878 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){ 3879 // Indexing over an interface, as in "NSString *P; P[4];" 3880 3881 // Emit the base pointer. 3882 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo); 3883 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 3884 3885 CharUnits InterfaceSize = getContext().getTypeSizeInChars(OIT); 3886 llvm::Value *InterfaceSizeVal = 3887 llvm::ConstantInt::get(Idx->getType(), InterfaceSize.getQuantity()); 3888 3889 llvm::Value *ScaledIdx = Builder.CreateMul(Idx, InterfaceSizeVal); 3890 3891 // We don't necessarily build correct LLVM struct types for ObjC 3892 // interfaces, so we can't rely on GEP to do this scaling 3893 // correctly, so we need to cast to i8*. FIXME: is this actually 3894 // true? A lot of other things in the fragile ABI would break... 3895 llvm::Type *OrigBaseElemTy = Addr.getElementType(); 3896 3897 // Do the GEP. 3898 CharUnits EltAlign = 3899 getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize); 3900 llvm::Value *EltPtr = 3901 emitArraySubscriptGEP(*this, Int8Ty, Addr.getPointer(), ScaledIdx, 3902 false, SignedIndices, E->getExprLoc()); 3903 Addr = Address(EltPtr, OrigBaseElemTy, EltAlign); 3904 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) { 3905 // If this is A[i] where A is an array, the frontend will have decayed the 3906 // base to be a ArrayToPointerDecay implicit cast. While correct, it is 3907 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a 3908 // "gep x, i" here. Emit one "gep A, 0, i". 3909 assert(Array->getType()->isArrayType() && 3910 "Array to pointer decay must have array source type!"); 3911 LValue ArrayLV; 3912 // For simple multidimensional array indexing, set the 'accessed' flag for 3913 // better bounds-checking of the base expression. 3914 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array)) 3915 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true); 3916 else 3917 ArrayLV = EmitLValue(Array); 3918 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 3919 3920 // Propagate the alignment from the array itself to the result. 3921 QualType arrayType = Array->getType(); 3922 Addr = emitArraySubscriptGEP( 3923 *this, ArrayLV.getAddress(*this), {CGM.getSize(CharUnits::Zero()), Idx}, 3924 E->getType(), !getLangOpts().isSignedOverflowDefined(), SignedIndices, 3925 E->getExprLoc(), &arrayType, E->getBase()); 3926 EltBaseInfo = ArrayLV.getBaseInfo(); 3927 EltTBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, E->getType()); 3928 } else { 3929 // The base must be a pointer; emit it with an estimate of its alignment. 3930 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo); 3931 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 3932 QualType ptrType = E->getBase()->getType(); 3933 Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(), 3934 !getLangOpts().isSignedOverflowDefined(), 3935 SignedIndices, E->getExprLoc(), &ptrType, 3936 E->getBase()); 3937 } 3938 3939 LValue LV = MakeAddrLValue(Addr, E->getType(), EltBaseInfo, EltTBAAInfo); 3940 3941 if (getLangOpts().ObjC && 3942 getLangOpts().getGC() != LangOptions::NonGC) { 3943 LV.setNonGC(!E->isOBJCGCCandidate(getContext())); 3944 setObjCGCLValueClass(getContext(), E, LV); 3945 } 3946 return LV; 3947 } 3948 3949 LValue CodeGenFunction::EmitMatrixSubscriptExpr(const MatrixSubscriptExpr *E) { 3950 assert( 3951 !E->isIncomplete() && 3952 "incomplete matrix subscript expressions should be rejected during Sema"); 3953 LValue Base = EmitLValue(E->getBase()); 3954 llvm::Value *RowIdx = EmitScalarExpr(E->getRowIdx()); 3955 llvm::Value *ColIdx = EmitScalarExpr(E->getColumnIdx()); 3956 llvm::Value *NumRows = Builder.getIntN( 3957 RowIdx->getType()->getScalarSizeInBits(), 3958 E->getBase()->getType()->castAs<ConstantMatrixType>()->getNumRows()); 3959 llvm::Value *FinalIdx = 3960 Builder.CreateAdd(Builder.CreateMul(ColIdx, NumRows), RowIdx); 3961 return LValue::MakeMatrixElt( 3962 MaybeConvertMatrixAddress(Base.getAddress(*this), *this), FinalIdx, 3963 E->getBase()->getType(), Base.getBaseInfo(), TBAAAccessInfo()); 3964 } 3965 3966 static Address emitOMPArraySectionBase(CodeGenFunction &CGF, const Expr *Base, 3967 LValueBaseInfo &BaseInfo, 3968 TBAAAccessInfo &TBAAInfo, 3969 QualType BaseTy, QualType ElTy, 3970 bool IsLowerBound) { 3971 LValue BaseLVal; 3972 if (auto *ASE = dyn_cast<OMPArraySectionExpr>(Base->IgnoreParenImpCasts())) { 3973 BaseLVal = CGF.EmitOMPArraySectionExpr(ASE, IsLowerBound); 3974 if (BaseTy->isArrayType()) { 3975 Address Addr = BaseLVal.getAddress(CGF); 3976 BaseInfo = BaseLVal.getBaseInfo(); 3977 3978 // If the array type was an incomplete type, we need to make sure 3979 // the decay ends up being the right type. 3980 llvm::Type *NewTy = CGF.ConvertType(BaseTy); 3981 Addr = Addr.withElementType(NewTy); 3982 3983 // Note that VLA pointers are always decayed, so we don't need to do 3984 // anything here. 3985 if (!BaseTy->isVariableArrayType()) { 3986 assert(isa<llvm::ArrayType>(Addr.getElementType()) && 3987 "Expected pointer to array"); 3988 Addr = CGF.Builder.CreateConstArrayGEP(Addr, 0, "arraydecay"); 3989 } 3990 3991 return Addr.withElementType(CGF.ConvertTypeForMem(ElTy)); 3992 } 3993 LValueBaseInfo TypeBaseInfo; 3994 TBAAAccessInfo TypeTBAAInfo; 3995 CharUnits Align = 3996 CGF.CGM.getNaturalTypeAlignment(ElTy, &TypeBaseInfo, &TypeTBAAInfo); 3997 BaseInfo.mergeForCast(TypeBaseInfo); 3998 TBAAInfo = CGF.CGM.mergeTBAAInfoForCast(TBAAInfo, TypeTBAAInfo); 3999 return Address(CGF.Builder.CreateLoad(BaseLVal.getAddress(CGF)), 4000 CGF.ConvertTypeForMem(ElTy), Align); 4001 } 4002 return CGF.EmitPointerWithAlignment(Base, &BaseInfo, &TBAAInfo); 4003 } 4004 4005 LValue CodeGenFunction::EmitOMPArraySectionExpr(const OMPArraySectionExpr *E, 4006 bool IsLowerBound) { 4007 QualType BaseTy = OMPArraySectionExpr::getBaseOriginalType(E->getBase()); 4008 QualType ResultExprTy; 4009 if (auto *AT = getContext().getAsArrayType(BaseTy)) 4010 ResultExprTy = AT->getElementType(); 4011 else 4012 ResultExprTy = BaseTy->getPointeeType(); 4013 llvm::Value *Idx = nullptr; 4014 if (IsLowerBound || E->getColonLocFirst().isInvalid()) { 4015 // Requesting lower bound or upper bound, but without provided length and 4016 // without ':' symbol for the default length -> length = 1. 4017 // Idx = LowerBound ?: 0; 4018 if (auto *LowerBound = E->getLowerBound()) { 4019 Idx = Builder.CreateIntCast( 4020 EmitScalarExpr(LowerBound), IntPtrTy, 4021 LowerBound->getType()->hasSignedIntegerRepresentation()); 4022 } else 4023 Idx = llvm::ConstantInt::getNullValue(IntPtrTy); 4024 } else { 4025 // Try to emit length or lower bound as constant. If this is possible, 1 4026 // is subtracted from constant length or lower bound. Otherwise, emit LLVM 4027 // IR (LB + Len) - 1. 4028 auto &C = CGM.getContext(); 4029 auto *Length = E->getLength(); 4030 llvm::APSInt ConstLength; 4031 if (Length) { 4032 // Idx = LowerBound + Length - 1; 4033 if (std::optional<llvm::APSInt> CL = Length->getIntegerConstantExpr(C)) { 4034 ConstLength = CL->zextOrTrunc(PointerWidthInBits); 4035 Length = nullptr; 4036 } 4037 auto *LowerBound = E->getLowerBound(); 4038 llvm::APSInt ConstLowerBound(PointerWidthInBits, /*isUnsigned=*/false); 4039 if (LowerBound) { 4040 if (std::optional<llvm::APSInt> LB = 4041 LowerBound->getIntegerConstantExpr(C)) { 4042 ConstLowerBound = LB->zextOrTrunc(PointerWidthInBits); 4043 LowerBound = nullptr; 4044 } 4045 } 4046 if (!Length) 4047 --ConstLength; 4048 else if (!LowerBound) 4049 --ConstLowerBound; 4050 4051 if (Length || LowerBound) { 4052 auto *LowerBoundVal = 4053 LowerBound 4054 ? Builder.CreateIntCast( 4055 EmitScalarExpr(LowerBound), IntPtrTy, 4056 LowerBound->getType()->hasSignedIntegerRepresentation()) 4057 : llvm::ConstantInt::get(IntPtrTy, ConstLowerBound); 4058 auto *LengthVal = 4059 Length 4060 ? Builder.CreateIntCast( 4061 EmitScalarExpr(Length), IntPtrTy, 4062 Length->getType()->hasSignedIntegerRepresentation()) 4063 : llvm::ConstantInt::get(IntPtrTy, ConstLength); 4064 Idx = Builder.CreateAdd(LowerBoundVal, LengthVal, "lb_add_len", 4065 /*HasNUW=*/false, 4066 !getLangOpts().isSignedOverflowDefined()); 4067 if (Length && LowerBound) { 4068 Idx = Builder.CreateSub( 4069 Idx, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "idx_sub_1", 4070 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined()); 4071 } 4072 } else 4073 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength + ConstLowerBound); 4074 } else { 4075 // Idx = ArraySize - 1; 4076 QualType ArrayTy = BaseTy->isPointerType() 4077 ? E->getBase()->IgnoreParenImpCasts()->getType() 4078 : BaseTy; 4079 if (auto *VAT = C.getAsVariableArrayType(ArrayTy)) { 4080 Length = VAT->getSizeExpr(); 4081 if (std::optional<llvm::APSInt> L = Length->getIntegerConstantExpr(C)) { 4082 ConstLength = *L; 4083 Length = nullptr; 4084 } 4085 } else { 4086 auto *CAT = C.getAsConstantArrayType(ArrayTy); 4087 assert(CAT && "unexpected type for array initializer"); 4088 ConstLength = CAT->getSize(); 4089 } 4090 if (Length) { 4091 auto *LengthVal = Builder.CreateIntCast( 4092 EmitScalarExpr(Length), IntPtrTy, 4093 Length->getType()->hasSignedIntegerRepresentation()); 4094 Idx = Builder.CreateSub( 4095 LengthVal, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "len_sub_1", 4096 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined()); 4097 } else { 4098 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits); 4099 --ConstLength; 4100 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength); 4101 } 4102 } 4103 } 4104 assert(Idx); 4105 4106 Address EltPtr = Address::invalid(); 4107 LValueBaseInfo BaseInfo; 4108 TBAAAccessInfo TBAAInfo; 4109 if (auto *VLA = getContext().getAsVariableArrayType(ResultExprTy)) { 4110 // The base must be a pointer, which is not an aggregate. Emit 4111 // it. It needs to be emitted first in case it's what captures 4112 // the VLA bounds. 4113 Address Base = 4114 emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, TBAAInfo, 4115 BaseTy, VLA->getElementType(), IsLowerBound); 4116 // The element count here is the total number of non-VLA elements. 4117 llvm::Value *NumElements = getVLASize(VLA).NumElts; 4118 4119 // Effectively, the multiply by the VLA size is part of the GEP. 4120 // GEP indexes are signed, and scaling an index isn't permitted to 4121 // signed-overflow, so we use the same semantics for our explicit 4122 // multiply. We suppress this if overflow is not undefined behavior. 4123 if (getLangOpts().isSignedOverflowDefined()) 4124 Idx = Builder.CreateMul(Idx, NumElements); 4125 else 4126 Idx = Builder.CreateNSWMul(Idx, NumElements); 4127 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(), 4128 !getLangOpts().isSignedOverflowDefined(), 4129 /*signedIndices=*/false, E->getExprLoc()); 4130 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) { 4131 // If this is A[i] where A is an array, the frontend will have decayed the 4132 // base to be a ArrayToPointerDecay implicit cast. While correct, it is 4133 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a 4134 // "gep x, i" here. Emit one "gep A, 0, i". 4135 assert(Array->getType()->isArrayType() && 4136 "Array to pointer decay must have array source type!"); 4137 LValue ArrayLV; 4138 // For simple multidimensional array indexing, set the 'accessed' flag for 4139 // better bounds-checking of the base expression. 4140 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array)) 4141 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true); 4142 else 4143 ArrayLV = EmitLValue(Array); 4144 4145 // Propagate the alignment from the array itself to the result. 4146 EltPtr = emitArraySubscriptGEP( 4147 *this, ArrayLV.getAddress(*this), {CGM.getSize(CharUnits::Zero()), Idx}, 4148 ResultExprTy, !getLangOpts().isSignedOverflowDefined(), 4149 /*signedIndices=*/false, E->getExprLoc()); 4150 BaseInfo = ArrayLV.getBaseInfo(); 4151 TBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, ResultExprTy); 4152 } else { 4153 Address Base = emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, 4154 TBAAInfo, BaseTy, ResultExprTy, 4155 IsLowerBound); 4156 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy, 4157 !getLangOpts().isSignedOverflowDefined(), 4158 /*signedIndices=*/false, E->getExprLoc()); 4159 } 4160 4161 return MakeAddrLValue(EltPtr, ResultExprTy, BaseInfo, TBAAInfo); 4162 } 4163 4164 LValue CodeGenFunction:: 4165 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) { 4166 // Emit the base vector as an l-value. 4167 LValue Base; 4168 4169 // ExtVectorElementExpr's base can either be a vector or pointer to vector. 4170 if (E->isArrow()) { 4171 // If it is a pointer to a vector, emit the address and form an lvalue with 4172 // it. 4173 LValueBaseInfo BaseInfo; 4174 TBAAAccessInfo TBAAInfo; 4175 Address Ptr = EmitPointerWithAlignment(E->getBase(), &BaseInfo, &TBAAInfo); 4176 const auto *PT = E->getBase()->getType()->castAs<PointerType>(); 4177 Base = MakeAddrLValue(Ptr, PT->getPointeeType(), BaseInfo, TBAAInfo); 4178 Base.getQuals().removeObjCGCAttr(); 4179 } else if (E->getBase()->isGLValue()) { 4180 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x), 4181 // emit the base as an lvalue. 4182 assert(E->getBase()->getType()->isVectorType()); 4183 Base = EmitLValue(E->getBase()); 4184 } else { 4185 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such. 4186 assert(E->getBase()->getType()->isVectorType() && 4187 "Result must be a vector"); 4188 llvm::Value *Vec = EmitScalarExpr(E->getBase()); 4189 4190 // Store the vector to memory (because LValue wants an address). 4191 Address VecMem = CreateMemTemp(E->getBase()->getType()); 4192 Builder.CreateStore(Vec, VecMem); 4193 Base = MakeAddrLValue(VecMem, E->getBase()->getType(), 4194 AlignmentSource::Decl); 4195 } 4196 4197 QualType type = 4198 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers()); 4199 4200 // Encode the element access list into a vector of unsigned indices. 4201 SmallVector<uint32_t, 4> Indices; 4202 E->getEncodedElementAccess(Indices); 4203 4204 if (Base.isSimple()) { 4205 llvm::Constant *CV = 4206 llvm::ConstantDataVector::get(getLLVMContext(), Indices); 4207 return LValue::MakeExtVectorElt(Base.getAddress(*this), CV, type, 4208 Base.getBaseInfo(), TBAAAccessInfo()); 4209 } 4210 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!"); 4211 4212 llvm::Constant *BaseElts = Base.getExtVectorElts(); 4213 SmallVector<llvm::Constant *, 4> CElts; 4214 4215 for (unsigned i = 0, e = Indices.size(); i != e; ++i) 4216 CElts.push_back(BaseElts->getAggregateElement(Indices[i])); 4217 llvm::Constant *CV = llvm::ConstantVector::get(CElts); 4218 return LValue::MakeExtVectorElt(Base.getExtVectorAddress(), CV, type, 4219 Base.getBaseInfo(), TBAAAccessInfo()); 4220 } 4221 4222 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) { 4223 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, E)) { 4224 EmitIgnoredExpr(E->getBase()); 4225 return EmitDeclRefLValue(DRE); 4226 } 4227 4228 Expr *BaseExpr = E->getBase(); 4229 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar. 4230 LValue BaseLV; 4231 if (E->isArrow()) { 4232 LValueBaseInfo BaseInfo; 4233 TBAAAccessInfo TBAAInfo; 4234 Address Addr = EmitPointerWithAlignment(BaseExpr, &BaseInfo, &TBAAInfo); 4235 QualType PtrTy = BaseExpr->getType()->getPointeeType(); 4236 SanitizerSet SkippedChecks; 4237 bool IsBaseCXXThis = IsWrappedCXXThis(BaseExpr); 4238 if (IsBaseCXXThis) 4239 SkippedChecks.set(SanitizerKind::Alignment, true); 4240 if (IsBaseCXXThis || isa<DeclRefExpr>(BaseExpr)) 4241 SkippedChecks.set(SanitizerKind::Null, true); 4242 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr.getPointer(), PtrTy, 4243 /*Alignment=*/CharUnits::Zero(), SkippedChecks); 4244 BaseLV = MakeAddrLValue(Addr, PtrTy, BaseInfo, TBAAInfo); 4245 } else 4246 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess); 4247 4248 NamedDecl *ND = E->getMemberDecl(); 4249 if (auto *Field = dyn_cast<FieldDecl>(ND)) { 4250 LValue LV = EmitLValueForField(BaseLV, Field); 4251 setObjCGCLValueClass(getContext(), E, LV); 4252 if (getLangOpts().OpenMP) { 4253 // If the member was explicitly marked as nontemporal, mark it as 4254 // nontemporal. If the base lvalue is marked as nontemporal, mark access 4255 // to children as nontemporal too. 4256 if ((IsWrappedCXXThis(BaseExpr) && 4257 CGM.getOpenMPRuntime().isNontemporalDecl(Field)) || 4258 BaseLV.isNontemporal()) 4259 LV.setNontemporal(/*Value=*/true); 4260 } 4261 return LV; 4262 } 4263 4264 if (const auto *FD = dyn_cast<FunctionDecl>(ND)) 4265 return EmitFunctionDeclLValue(*this, E, FD); 4266 4267 llvm_unreachable("Unhandled member declaration!"); 4268 } 4269 4270 /// Given that we are currently emitting a lambda, emit an l-value for 4271 /// one of its members. 4272 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) { 4273 if (CurCodeDecl) { 4274 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent()->isLambda()); 4275 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent() == Field->getParent()); 4276 } 4277 QualType LambdaTagType = 4278 getContext().getTagDeclType(Field->getParent()); 4279 LValue LambdaLV = MakeNaturalAlignAddrLValue(CXXABIThisValue, LambdaTagType); 4280 return EmitLValueForField(LambdaLV, Field); 4281 } 4282 4283 /// Get the field index in the debug info. The debug info structure/union 4284 /// will ignore the unnamed bitfields. 4285 unsigned CodeGenFunction::getDebugInfoFIndex(const RecordDecl *Rec, 4286 unsigned FieldIndex) { 4287 unsigned I = 0, Skipped = 0; 4288 4289 for (auto *F : Rec->getDefinition()->fields()) { 4290 if (I == FieldIndex) 4291 break; 4292 if (F->isUnnamedBitfield()) 4293 Skipped++; 4294 I++; 4295 } 4296 4297 return FieldIndex - Skipped; 4298 } 4299 4300 /// Get the address of a zero-sized field within a record. The resulting 4301 /// address doesn't necessarily have the right type. 4302 static Address emitAddrOfZeroSizeField(CodeGenFunction &CGF, Address Base, 4303 const FieldDecl *Field) { 4304 CharUnits Offset = CGF.getContext().toCharUnitsFromBits( 4305 CGF.getContext().getFieldOffset(Field)); 4306 if (Offset.isZero()) 4307 return Base; 4308 Base = Base.withElementType(CGF.Int8Ty); 4309 return CGF.Builder.CreateConstInBoundsByteGEP(Base, Offset); 4310 } 4311 4312 /// Drill down to the storage of a field without walking into 4313 /// reference types. 4314 /// 4315 /// The resulting address doesn't necessarily have the right type. 4316 static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base, 4317 const FieldDecl *field) { 4318 if (field->isZeroSize(CGF.getContext())) 4319 return emitAddrOfZeroSizeField(CGF, base, field); 4320 4321 const RecordDecl *rec = field->getParent(); 4322 4323 unsigned idx = 4324 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field); 4325 4326 return CGF.Builder.CreateStructGEP(base, idx, field->getName()); 4327 } 4328 4329 static Address emitPreserveStructAccess(CodeGenFunction &CGF, LValue base, 4330 Address addr, const FieldDecl *field) { 4331 const RecordDecl *rec = field->getParent(); 4332 llvm::DIType *DbgInfo = CGF.getDebugInfo()->getOrCreateStandaloneType( 4333 base.getType(), rec->getLocation()); 4334 4335 unsigned idx = 4336 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field); 4337 4338 return CGF.Builder.CreatePreserveStructAccessIndex( 4339 addr, idx, CGF.getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo); 4340 } 4341 4342 static bool hasAnyVptr(const QualType Type, const ASTContext &Context) { 4343 const auto *RD = Type.getTypePtr()->getAsCXXRecordDecl(); 4344 if (!RD) 4345 return false; 4346 4347 if (RD->isDynamicClass()) 4348 return true; 4349 4350 for (const auto &Base : RD->bases()) 4351 if (hasAnyVptr(Base.getType(), Context)) 4352 return true; 4353 4354 for (const FieldDecl *Field : RD->fields()) 4355 if (hasAnyVptr(Field->getType(), Context)) 4356 return true; 4357 4358 return false; 4359 } 4360 4361 LValue CodeGenFunction::EmitLValueForField(LValue base, 4362 const FieldDecl *field) { 4363 LValueBaseInfo BaseInfo = base.getBaseInfo(); 4364 4365 if (field->isBitField()) { 4366 const CGRecordLayout &RL = 4367 CGM.getTypes().getCGRecordLayout(field->getParent()); 4368 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field); 4369 const bool UseVolatile = isAAPCS(CGM.getTarget()) && 4370 CGM.getCodeGenOpts().AAPCSBitfieldWidth && 4371 Info.VolatileStorageSize != 0 && 4372 field->getType() 4373 .withCVRQualifiers(base.getVRQualifiers()) 4374 .isVolatileQualified(); 4375 Address Addr = base.getAddress(*this); 4376 unsigned Idx = RL.getLLVMFieldNo(field); 4377 const RecordDecl *rec = field->getParent(); 4378 if (!UseVolatile) { 4379 if (!IsInPreservedAIRegion && 4380 (!getDebugInfo() || !rec->hasAttr<BPFPreserveAccessIndexAttr>())) { 4381 if (Idx != 0) 4382 // For structs, we GEP to the field that the record layout suggests. 4383 Addr = Builder.CreateStructGEP(Addr, Idx, field->getName()); 4384 } else { 4385 llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateRecordType( 4386 getContext().getRecordType(rec), rec->getLocation()); 4387 Addr = Builder.CreatePreserveStructAccessIndex( 4388 Addr, Idx, getDebugInfoFIndex(rec, field->getFieldIndex()), 4389 DbgInfo); 4390 } 4391 } 4392 const unsigned SS = 4393 UseVolatile ? Info.VolatileStorageSize : Info.StorageSize; 4394 // Get the access type. 4395 llvm::Type *FieldIntTy = llvm::Type::getIntNTy(getLLVMContext(), SS); 4396 Addr = Addr.withElementType(FieldIntTy); 4397 if (UseVolatile) { 4398 const unsigned VolatileOffset = Info.VolatileStorageOffset.getQuantity(); 4399 if (VolatileOffset) 4400 Addr = Builder.CreateConstInBoundsGEP(Addr, VolatileOffset); 4401 } 4402 4403 QualType fieldType = 4404 field->getType().withCVRQualifiers(base.getVRQualifiers()); 4405 // TODO: Support TBAA for bit fields. 4406 LValueBaseInfo FieldBaseInfo(BaseInfo.getAlignmentSource()); 4407 return LValue::MakeBitfield(Addr, Info, fieldType, FieldBaseInfo, 4408 TBAAAccessInfo()); 4409 } 4410 4411 // Fields of may-alias structures are may-alias themselves. 4412 // FIXME: this should get propagated down through anonymous structs 4413 // and unions. 4414 QualType FieldType = field->getType(); 4415 const RecordDecl *rec = field->getParent(); 4416 AlignmentSource BaseAlignSource = BaseInfo.getAlignmentSource(); 4417 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(BaseAlignSource)); 4418 TBAAAccessInfo FieldTBAAInfo; 4419 if (base.getTBAAInfo().isMayAlias() || 4420 rec->hasAttr<MayAliasAttr>() || FieldType->isVectorType()) { 4421 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo(); 4422 } else if (rec->isUnion()) { 4423 // TODO: Support TBAA for unions. 4424 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo(); 4425 } else { 4426 // If no base type been assigned for the base access, then try to generate 4427 // one for this base lvalue. 4428 FieldTBAAInfo = base.getTBAAInfo(); 4429 if (!FieldTBAAInfo.BaseType) { 4430 FieldTBAAInfo.BaseType = CGM.getTBAABaseTypeInfo(base.getType()); 4431 assert(!FieldTBAAInfo.Offset && 4432 "Nonzero offset for an access with no base type!"); 4433 } 4434 4435 // Adjust offset to be relative to the base type. 4436 const ASTRecordLayout &Layout = 4437 getContext().getASTRecordLayout(field->getParent()); 4438 unsigned CharWidth = getContext().getCharWidth(); 4439 if (FieldTBAAInfo.BaseType) 4440 FieldTBAAInfo.Offset += 4441 Layout.getFieldOffset(field->getFieldIndex()) / CharWidth; 4442 4443 // Update the final access type and size. 4444 FieldTBAAInfo.AccessType = CGM.getTBAATypeInfo(FieldType); 4445 FieldTBAAInfo.Size = 4446 getContext().getTypeSizeInChars(FieldType).getQuantity(); 4447 } 4448 4449 Address addr = base.getAddress(*this); 4450 if (auto *ClassDef = dyn_cast<CXXRecordDecl>(rec)) { 4451 if (CGM.getCodeGenOpts().StrictVTablePointers && 4452 ClassDef->isDynamicClass()) { 4453 // Getting to any field of dynamic object requires stripping dynamic 4454 // information provided by invariant.group. This is because accessing 4455 // fields may leak the real address of dynamic object, which could result 4456 // in miscompilation when leaked pointer would be compared. 4457 auto *stripped = Builder.CreateStripInvariantGroup(addr.getPointer()); 4458 addr = Address(stripped, addr.getElementType(), addr.getAlignment()); 4459 } 4460 } 4461 4462 unsigned RecordCVR = base.getVRQualifiers(); 4463 if (rec->isUnion()) { 4464 // For unions, there is no pointer adjustment. 4465 if (CGM.getCodeGenOpts().StrictVTablePointers && 4466 hasAnyVptr(FieldType, getContext())) 4467 // Because unions can easily skip invariant.barriers, we need to add 4468 // a barrier every time CXXRecord field with vptr is referenced. 4469 addr = Builder.CreateLaunderInvariantGroup(addr); 4470 4471 if (IsInPreservedAIRegion || 4472 (getDebugInfo() && rec->hasAttr<BPFPreserveAccessIndexAttr>())) { 4473 // Remember the original union field index 4474 llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateStandaloneType(base.getType(), 4475 rec->getLocation()); 4476 addr = Address( 4477 Builder.CreatePreserveUnionAccessIndex( 4478 addr.getPointer(), getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo), 4479 addr.getElementType(), addr.getAlignment()); 4480 } 4481 4482 if (FieldType->isReferenceType()) 4483 addr = addr.withElementType(CGM.getTypes().ConvertTypeForMem(FieldType)); 4484 } else { 4485 if (!IsInPreservedAIRegion && 4486 (!getDebugInfo() || !rec->hasAttr<BPFPreserveAccessIndexAttr>())) 4487 // For structs, we GEP to the field that the record layout suggests. 4488 addr = emitAddrOfFieldStorage(*this, addr, field); 4489 else 4490 // Remember the original struct field index 4491 addr = emitPreserveStructAccess(*this, base, addr, field); 4492 } 4493 4494 // If this is a reference field, load the reference right now. 4495 if (FieldType->isReferenceType()) { 4496 LValue RefLVal = 4497 MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo); 4498 if (RecordCVR & Qualifiers::Volatile) 4499 RefLVal.getQuals().addVolatile(); 4500 addr = EmitLoadOfReference(RefLVal, &FieldBaseInfo, &FieldTBAAInfo); 4501 4502 // Qualifiers on the struct don't apply to the referencee. 4503 RecordCVR = 0; 4504 FieldType = FieldType->getPointeeType(); 4505 } 4506 4507 // Make sure that the address is pointing to the right type. This is critical 4508 // for both unions and structs. 4509 addr = addr.withElementType(CGM.getTypes().ConvertTypeForMem(FieldType)); 4510 4511 if (field->hasAttr<AnnotateAttr>()) 4512 addr = EmitFieldAnnotations(field, addr); 4513 4514 LValue LV = MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo); 4515 LV.getQuals().addCVRQualifiers(RecordCVR); 4516 4517 // __weak attribute on a field is ignored. 4518 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak) 4519 LV.getQuals().removeObjCGCAttr(); 4520 4521 return LV; 4522 } 4523 4524 LValue 4525 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base, 4526 const FieldDecl *Field) { 4527 QualType FieldType = Field->getType(); 4528 4529 if (!FieldType->isReferenceType()) 4530 return EmitLValueForField(Base, Field); 4531 4532 Address V = emitAddrOfFieldStorage(*this, Base.getAddress(*this), Field); 4533 4534 // Make sure that the address is pointing to the right type. 4535 llvm::Type *llvmType = ConvertTypeForMem(FieldType); 4536 V = V.withElementType(llvmType); 4537 4538 // TODO: Generate TBAA information that describes this access as a structure 4539 // member access and not just an access to an object of the field's type. This 4540 // should be similar to what we do in EmitLValueForField(). 4541 LValueBaseInfo BaseInfo = Base.getBaseInfo(); 4542 AlignmentSource FieldAlignSource = BaseInfo.getAlignmentSource(); 4543 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(FieldAlignSource)); 4544 return MakeAddrLValue(V, FieldType, FieldBaseInfo, 4545 CGM.getTBAAInfoForSubobject(Base, FieldType)); 4546 } 4547 4548 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){ 4549 if (E->isFileScope()) { 4550 ConstantAddress GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E); 4551 return MakeAddrLValue(GlobalPtr, E->getType(), AlignmentSource::Decl); 4552 } 4553 if (E->getType()->isVariablyModifiedType()) 4554 // make sure to emit the VLA size. 4555 EmitVariablyModifiedType(E->getType()); 4556 4557 Address DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral"); 4558 const Expr *InitExpr = E->getInitializer(); 4559 LValue Result = MakeAddrLValue(DeclPtr, E->getType(), AlignmentSource::Decl); 4560 4561 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(), 4562 /*Init*/ true); 4563 4564 // Block-scope compound literals are destroyed at the end of the enclosing 4565 // scope in C. 4566 if (!getLangOpts().CPlusPlus) 4567 if (QualType::DestructionKind DtorKind = E->getType().isDestructedType()) 4568 pushLifetimeExtendedDestroy(getCleanupKind(DtorKind), DeclPtr, 4569 E->getType(), getDestroyer(DtorKind), 4570 DtorKind & EHCleanup); 4571 4572 return Result; 4573 } 4574 4575 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) { 4576 if (!E->isGLValue()) 4577 // Initializing an aggregate temporary in C++11: T{...}. 4578 return EmitAggExprToLValue(E); 4579 4580 // An lvalue initializer list must be initializing a reference. 4581 assert(E->isTransparent() && "non-transparent glvalue init list"); 4582 return EmitLValue(E->getInit(0)); 4583 } 4584 4585 /// Emit the operand of a glvalue conditional operator. This is either a glvalue 4586 /// or a (possibly-parenthesized) throw-expression. If this is a throw, no 4587 /// LValue is returned and the current block has been terminated. 4588 static std::optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF, 4589 const Expr *Operand) { 4590 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) { 4591 CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false); 4592 return std::nullopt; 4593 } 4594 4595 return CGF.EmitLValue(Operand); 4596 } 4597 4598 namespace { 4599 // Handle the case where the condition is a constant evaluatable simple integer, 4600 // which means we don't have to separately handle the true/false blocks. 4601 std::optional<LValue> HandleConditionalOperatorLValueSimpleCase( 4602 CodeGenFunction &CGF, const AbstractConditionalOperator *E) { 4603 const Expr *condExpr = E->getCond(); 4604 bool CondExprBool; 4605 if (CGF.ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) { 4606 const Expr *Live = E->getTrueExpr(), *Dead = E->getFalseExpr(); 4607 if (!CondExprBool) 4608 std::swap(Live, Dead); 4609 4610 if (!CGF.ContainsLabel(Dead)) { 4611 // If the true case is live, we need to track its region. 4612 if (CondExprBool) 4613 CGF.incrementProfileCounter(E); 4614 // If a throw expression we emit it and return an undefined lvalue 4615 // because it can't be used. 4616 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Live->IgnoreParens())) { 4617 CGF.EmitCXXThrowExpr(ThrowExpr); 4618 llvm::Type *ElemTy = CGF.ConvertType(Dead->getType()); 4619 llvm::Type *Ty = llvm::PointerType::getUnqual(ElemTy); 4620 return CGF.MakeAddrLValue( 4621 Address(llvm::UndefValue::get(Ty), ElemTy, CharUnits::One()), 4622 Dead->getType()); 4623 } 4624 return CGF.EmitLValue(Live); 4625 } 4626 } 4627 return std::nullopt; 4628 } 4629 struct ConditionalInfo { 4630 llvm::BasicBlock *lhsBlock, *rhsBlock; 4631 std::optional<LValue> LHS, RHS; 4632 }; 4633 4634 // Create and generate the 3 blocks for a conditional operator. 4635 // Leaves the 'current block' in the continuation basic block. 4636 template<typename FuncTy> 4637 ConditionalInfo EmitConditionalBlocks(CodeGenFunction &CGF, 4638 const AbstractConditionalOperator *E, 4639 const FuncTy &BranchGenFunc) { 4640 ConditionalInfo Info{CGF.createBasicBlock("cond.true"), 4641 CGF.createBasicBlock("cond.false"), std::nullopt, 4642 std::nullopt}; 4643 llvm::BasicBlock *endBlock = CGF.createBasicBlock("cond.end"); 4644 4645 CodeGenFunction::ConditionalEvaluation eval(CGF); 4646 CGF.EmitBranchOnBoolExpr(E->getCond(), Info.lhsBlock, Info.rhsBlock, 4647 CGF.getProfileCount(E)); 4648 4649 // Any temporaries created here are conditional. 4650 CGF.EmitBlock(Info.lhsBlock); 4651 CGF.incrementProfileCounter(E); 4652 eval.begin(CGF); 4653 Info.LHS = BranchGenFunc(CGF, E->getTrueExpr()); 4654 eval.end(CGF); 4655 Info.lhsBlock = CGF.Builder.GetInsertBlock(); 4656 4657 if (Info.LHS) 4658 CGF.Builder.CreateBr(endBlock); 4659 4660 // Any temporaries created here are conditional. 4661 CGF.EmitBlock(Info.rhsBlock); 4662 eval.begin(CGF); 4663 Info.RHS = BranchGenFunc(CGF, E->getFalseExpr()); 4664 eval.end(CGF); 4665 Info.rhsBlock = CGF.Builder.GetInsertBlock(); 4666 CGF.EmitBlock(endBlock); 4667 4668 return Info; 4669 } 4670 } // namespace 4671 4672 void CodeGenFunction::EmitIgnoredConditionalOperator( 4673 const AbstractConditionalOperator *E) { 4674 if (!E->isGLValue()) { 4675 // ?: here should be an aggregate. 4676 assert(hasAggregateEvaluationKind(E->getType()) && 4677 "Unexpected conditional operator!"); 4678 return (void)EmitAggExprToLValue(E); 4679 } 4680 4681 OpaqueValueMapping binding(*this, E); 4682 if (HandleConditionalOperatorLValueSimpleCase(*this, E)) 4683 return; 4684 4685 EmitConditionalBlocks(*this, E, [](CodeGenFunction &CGF, const Expr *E) { 4686 CGF.EmitIgnoredExpr(E); 4687 return LValue{}; 4688 }); 4689 } 4690 LValue CodeGenFunction::EmitConditionalOperatorLValue( 4691 const AbstractConditionalOperator *expr) { 4692 if (!expr->isGLValue()) { 4693 // ?: here should be an aggregate. 4694 assert(hasAggregateEvaluationKind(expr->getType()) && 4695 "Unexpected conditional operator!"); 4696 return EmitAggExprToLValue(expr); 4697 } 4698 4699 OpaqueValueMapping binding(*this, expr); 4700 if (std::optional<LValue> Res = 4701 HandleConditionalOperatorLValueSimpleCase(*this, expr)) 4702 return *Res; 4703 4704 ConditionalInfo Info = EmitConditionalBlocks( 4705 *this, expr, [](CodeGenFunction &CGF, const Expr *E) { 4706 return EmitLValueOrThrowExpression(CGF, E); 4707 }); 4708 4709 if ((Info.LHS && !Info.LHS->isSimple()) || 4710 (Info.RHS && !Info.RHS->isSimple())) 4711 return EmitUnsupportedLValue(expr, "conditional operator"); 4712 4713 if (Info.LHS && Info.RHS) { 4714 Address lhsAddr = Info.LHS->getAddress(*this); 4715 Address rhsAddr = Info.RHS->getAddress(*this); 4716 llvm::PHINode *phi = Builder.CreatePHI(lhsAddr.getType(), 2, "cond-lvalue"); 4717 phi->addIncoming(lhsAddr.getPointer(), Info.lhsBlock); 4718 phi->addIncoming(rhsAddr.getPointer(), Info.rhsBlock); 4719 Address result(phi, lhsAddr.getElementType(), 4720 std::min(lhsAddr.getAlignment(), rhsAddr.getAlignment())); 4721 AlignmentSource alignSource = 4722 std::max(Info.LHS->getBaseInfo().getAlignmentSource(), 4723 Info.RHS->getBaseInfo().getAlignmentSource()); 4724 TBAAAccessInfo TBAAInfo = CGM.mergeTBAAInfoForConditionalOperator( 4725 Info.LHS->getTBAAInfo(), Info.RHS->getTBAAInfo()); 4726 return MakeAddrLValue(result, expr->getType(), LValueBaseInfo(alignSource), 4727 TBAAInfo); 4728 } else { 4729 assert((Info.LHS || Info.RHS) && 4730 "both operands of glvalue conditional are throw-expressions?"); 4731 return Info.LHS ? *Info.LHS : *Info.RHS; 4732 } 4733 } 4734 4735 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference 4736 /// type. If the cast is to a reference, we can have the usual lvalue result, 4737 /// otherwise if a cast is needed by the code generator in an lvalue context, 4738 /// then it must mean that we need the address of an aggregate in order to 4739 /// access one of its members. This can happen for all the reasons that casts 4740 /// are permitted with aggregate result, including noop aggregate casts, and 4741 /// cast from scalar to union. 4742 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) { 4743 switch (E->getCastKind()) { 4744 case CK_ToVoid: 4745 case CK_BitCast: 4746 case CK_LValueToRValueBitCast: 4747 case CK_ArrayToPointerDecay: 4748 case CK_FunctionToPointerDecay: 4749 case CK_NullToMemberPointer: 4750 case CK_NullToPointer: 4751 case CK_IntegralToPointer: 4752 case CK_PointerToIntegral: 4753 case CK_PointerToBoolean: 4754 case CK_VectorSplat: 4755 case CK_IntegralCast: 4756 case CK_BooleanToSignedIntegral: 4757 case CK_IntegralToBoolean: 4758 case CK_IntegralToFloating: 4759 case CK_FloatingToIntegral: 4760 case CK_FloatingToBoolean: 4761 case CK_FloatingCast: 4762 case CK_FloatingRealToComplex: 4763 case CK_FloatingComplexToReal: 4764 case CK_FloatingComplexToBoolean: 4765 case CK_FloatingComplexCast: 4766 case CK_FloatingComplexToIntegralComplex: 4767 case CK_IntegralRealToComplex: 4768 case CK_IntegralComplexToReal: 4769 case CK_IntegralComplexToBoolean: 4770 case CK_IntegralComplexCast: 4771 case CK_IntegralComplexToFloatingComplex: 4772 case CK_DerivedToBaseMemberPointer: 4773 case CK_BaseToDerivedMemberPointer: 4774 case CK_MemberPointerToBoolean: 4775 case CK_ReinterpretMemberPointer: 4776 case CK_AnyPointerToBlockPointerCast: 4777 case CK_ARCProduceObject: 4778 case CK_ARCConsumeObject: 4779 case CK_ARCReclaimReturnedObject: 4780 case CK_ARCExtendBlockObject: 4781 case CK_CopyAndAutoreleaseBlockObject: 4782 case CK_IntToOCLSampler: 4783 case CK_FloatingToFixedPoint: 4784 case CK_FixedPointToFloating: 4785 case CK_FixedPointCast: 4786 case CK_FixedPointToBoolean: 4787 case CK_FixedPointToIntegral: 4788 case CK_IntegralToFixedPoint: 4789 case CK_MatrixCast: 4790 return EmitUnsupportedLValue(E, "unexpected cast lvalue"); 4791 4792 case CK_Dependent: 4793 llvm_unreachable("dependent cast kind in IR gen!"); 4794 4795 case CK_BuiltinFnToFnPtr: 4796 llvm_unreachable("builtin functions are handled elsewhere"); 4797 4798 // These are never l-values; just use the aggregate emission code. 4799 case CK_NonAtomicToAtomic: 4800 case CK_AtomicToNonAtomic: 4801 return EmitAggExprToLValue(E); 4802 4803 case CK_Dynamic: { 4804 LValue LV = EmitLValue(E->getSubExpr()); 4805 Address V = LV.getAddress(*this); 4806 const auto *DCE = cast<CXXDynamicCastExpr>(E); 4807 return MakeNaturalAlignAddrLValue(EmitDynamicCast(V, DCE), E->getType()); 4808 } 4809 4810 case CK_ConstructorConversion: 4811 case CK_UserDefinedConversion: 4812 case CK_CPointerToObjCPointerCast: 4813 case CK_BlockPointerToObjCPointerCast: 4814 case CK_LValueToRValue: 4815 return EmitLValue(E->getSubExpr()); 4816 4817 case CK_NoOp: { 4818 // CK_NoOp can model a qualification conversion, which can remove an array 4819 // bound and change the IR type. 4820 // FIXME: Once pointee types are removed from IR, remove this. 4821 LValue LV = EmitLValue(E->getSubExpr()); 4822 if (LV.isSimple()) { 4823 Address V = LV.getAddress(*this); 4824 if (V.isValid()) { 4825 llvm::Type *T = ConvertTypeForMem(E->getType()); 4826 if (V.getElementType() != T) 4827 LV.setAddress(V.withElementType(T)); 4828 } 4829 } 4830 return LV; 4831 } 4832 4833 case CK_UncheckedDerivedToBase: 4834 case CK_DerivedToBase: { 4835 const auto *DerivedClassTy = 4836 E->getSubExpr()->getType()->castAs<RecordType>(); 4837 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 4838 4839 LValue LV = EmitLValue(E->getSubExpr()); 4840 Address This = LV.getAddress(*this); 4841 4842 // Perform the derived-to-base conversion 4843 Address Base = GetAddressOfBaseClass( 4844 This, DerivedClassDecl, E->path_begin(), E->path_end(), 4845 /*NullCheckValue=*/false, E->getExprLoc()); 4846 4847 // TODO: Support accesses to members of base classes in TBAA. For now, we 4848 // conservatively pretend that the complete object is of the base class 4849 // type. 4850 return MakeAddrLValue(Base, E->getType(), LV.getBaseInfo(), 4851 CGM.getTBAAInfoForSubobject(LV, E->getType())); 4852 } 4853 case CK_ToUnion: 4854 return EmitAggExprToLValue(E); 4855 case CK_BaseToDerived: { 4856 const auto *DerivedClassTy = E->getType()->castAs<RecordType>(); 4857 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 4858 4859 LValue LV = EmitLValue(E->getSubExpr()); 4860 4861 // Perform the base-to-derived conversion 4862 Address Derived = GetAddressOfDerivedClass( 4863 LV.getAddress(*this), DerivedClassDecl, E->path_begin(), E->path_end(), 4864 /*NullCheckValue=*/false); 4865 4866 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is 4867 // performed and the object is not of the derived type. 4868 if (sanitizePerformTypeCheck()) 4869 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(), 4870 Derived.getPointer(), E->getType()); 4871 4872 if (SanOpts.has(SanitizerKind::CFIDerivedCast)) 4873 EmitVTablePtrCheckForCast(E->getType(), Derived, 4874 /*MayBeNull=*/false, CFITCK_DerivedCast, 4875 E->getBeginLoc()); 4876 4877 return MakeAddrLValue(Derived, E->getType(), LV.getBaseInfo(), 4878 CGM.getTBAAInfoForSubobject(LV, E->getType())); 4879 } 4880 case CK_LValueBitCast: { 4881 // This must be a reinterpret_cast (or c-style equivalent). 4882 const auto *CE = cast<ExplicitCastExpr>(E); 4883 4884 CGM.EmitExplicitCastExprType(CE, this); 4885 LValue LV = EmitLValue(E->getSubExpr()); 4886 Address V = LV.getAddress(*this).withElementType( 4887 ConvertTypeForMem(CE->getTypeAsWritten()->getPointeeType())); 4888 4889 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast)) 4890 EmitVTablePtrCheckForCast(E->getType(), V, 4891 /*MayBeNull=*/false, CFITCK_UnrelatedCast, 4892 E->getBeginLoc()); 4893 4894 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(), 4895 CGM.getTBAAInfoForSubobject(LV, E->getType())); 4896 } 4897 case CK_AddressSpaceConversion: { 4898 LValue LV = EmitLValue(E->getSubExpr()); 4899 QualType DestTy = getContext().getPointerType(E->getType()); 4900 llvm::Value *V = getTargetHooks().performAddrSpaceCast( 4901 *this, LV.getPointer(*this), 4902 E->getSubExpr()->getType().getAddressSpace(), 4903 E->getType().getAddressSpace(), ConvertType(DestTy)); 4904 return MakeAddrLValue(Address(V, ConvertTypeForMem(E->getType()), 4905 LV.getAddress(*this).getAlignment()), 4906 E->getType(), LV.getBaseInfo(), LV.getTBAAInfo()); 4907 } 4908 case CK_ObjCObjectLValueCast: { 4909 LValue LV = EmitLValue(E->getSubExpr()); 4910 Address V = LV.getAddress(*this).withElementType(ConvertType(E->getType())); 4911 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(), 4912 CGM.getTBAAInfoForSubobject(LV, E->getType())); 4913 } 4914 case CK_ZeroToOCLOpaqueType: 4915 llvm_unreachable("NULL to OpenCL opaque type lvalue cast is not valid"); 4916 } 4917 4918 llvm_unreachable("Unhandled lvalue cast kind?"); 4919 } 4920 4921 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) { 4922 assert(OpaqueValueMappingData::shouldBindAsLValue(e)); 4923 return getOrCreateOpaqueLValueMapping(e); 4924 } 4925 4926 LValue 4927 CodeGenFunction::getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e) { 4928 assert(OpaqueValueMapping::shouldBindAsLValue(e)); 4929 4930 llvm::DenseMap<const OpaqueValueExpr*,LValue>::iterator 4931 it = OpaqueLValues.find(e); 4932 4933 if (it != OpaqueLValues.end()) 4934 return it->second; 4935 4936 assert(e->isUnique() && "LValue for a nonunique OVE hasn't been emitted"); 4937 return EmitLValue(e->getSourceExpr()); 4938 } 4939 4940 RValue 4941 CodeGenFunction::getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e) { 4942 assert(!OpaqueValueMapping::shouldBindAsLValue(e)); 4943 4944 llvm::DenseMap<const OpaqueValueExpr*,RValue>::iterator 4945 it = OpaqueRValues.find(e); 4946 4947 if (it != OpaqueRValues.end()) 4948 return it->second; 4949 4950 assert(e->isUnique() && "RValue for a nonunique OVE hasn't been emitted"); 4951 return EmitAnyExpr(e->getSourceExpr()); 4952 } 4953 4954 RValue CodeGenFunction::EmitRValueForField(LValue LV, 4955 const FieldDecl *FD, 4956 SourceLocation Loc) { 4957 QualType FT = FD->getType(); 4958 LValue FieldLV = EmitLValueForField(LV, FD); 4959 switch (getEvaluationKind(FT)) { 4960 case TEK_Complex: 4961 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc)); 4962 case TEK_Aggregate: 4963 return FieldLV.asAggregateRValue(*this); 4964 case TEK_Scalar: 4965 // This routine is used to load fields one-by-one to perform a copy, so 4966 // don't load reference fields. 4967 if (FD->getType()->isReferenceType()) 4968 return RValue::get(FieldLV.getPointer(*this)); 4969 // Call EmitLoadOfScalar except when the lvalue is a bitfield to emit a 4970 // primitive load. 4971 if (FieldLV.isBitField()) 4972 return EmitLoadOfLValue(FieldLV, Loc); 4973 return RValue::get(EmitLoadOfScalar(FieldLV, Loc)); 4974 } 4975 llvm_unreachable("bad evaluation kind"); 4976 } 4977 4978 //===--------------------------------------------------------------------===// 4979 // Expression Emission 4980 //===--------------------------------------------------------------------===// 4981 4982 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E, 4983 ReturnValueSlot ReturnValue) { 4984 // Builtins never have block type. 4985 if (E->getCallee()->getType()->isBlockPointerType()) 4986 return EmitBlockCallExpr(E, ReturnValue); 4987 4988 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E)) 4989 return EmitCXXMemberCallExpr(CE, ReturnValue); 4990 4991 if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E)) 4992 return EmitCUDAKernelCallExpr(CE, ReturnValue); 4993 4994 if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E)) 4995 if (const CXXMethodDecl *MD = 4996 dyn_cast_or_null<CXXMethodDecl>(CE->getCalleeDecl())) 4997 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue); 4998 4999 CGCallee callee = EmitCallee(E->getCallee()); 5000 5001 if (callee.isBuiltin()) { 5002 return EmitBuiltinExpr(callee.getBuiltinDecl(), callee.getBuiltinID(), 5003 E, ReturnValue); 5004 } 5005 5006 if (callee.isPseudoDestructor()) { 5007 return EmitCXXPseudoDestructorExpr(callee.getPseudoDestructorExpr()); 5008 } 5009 5010 return EmitCall(E->getCallee()->getType(), callee, E, ReturnValue); 5011 } 5012 5013 /// Emit a CallExpr without considering whether it might be a subclass. 5014 RValue CodeGenFunction::EmitSimpleCallExpr(const CallExpr *E, 5015 ReturnValueSlot ReturnValue) { 5016 CGCallee Callee = EmitCallee(E->getCallee()); 5017 return EmitCall(E->getCallee()->getType(), Callee, E, ReturnValue); 5018 } 5019 5020 // Detect the unusual situation where an inline version is shadowed by a 5021 // non-inline version. In that case we should pick the external one 5022 // everywhere. That's GCC behavior too. 5023 static bool OnlyHasInlineBuiltinDeclaration(const FunctionDecl *FD) { 5024 for (const FunctionDecl *PD = FD; PD; PD = PD->getPreviousDecl()) 5025 if (!PD->isInlineBuiltinDeclaration()) 5026 return false; 5027 return true; 5028 } 5029 5030 static CGCallee EmitDirectCallee(CodeGenFunction &CGF, GlobalDecl GD) { 5031 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 5032 5033 if (auto builtinID = FD->getBuiltinID()) { 5034 std::string NoBuiltinFD = ("no-builtin-" + FD->getName()).str(); 5035 std::string NoBuiltins = "no-builtins"; 5036 5037 StringRef Ident = CGF.CGM.getMangledName(GD); 5038 std::string FDInlineName = (Ident + ".inline").str(); 5039 5040 bool IsPredefinedLibFunction = 5041 CGF.getContext().BuiltinInfo.isPredefinedLibFunction(builtinID); 5042 bool HasAttributeNoBuiltin = 5043 CGF.CurFn->getAttributes().hasFnAttr(NoBuiltinFD) || 5044 CGF.CurFn->getAttributes().hasFnAttr(NoBuiltins); 5045 5046 // When directing calling an inline builtin, call it through it's mangled 5047 // name to make it clear it's not the actual builtin. 5048 if (CGF.CurFn->getName() != FDInlineName && 5049 OnlyHasInlineBuiltinDeclaration(FD)) { 5050 llvm::Constant *CalleePtr = EmitFunctionDeclPointer(CGF.CGM, GD); 5051 llvm::Function *Fn = llvm::cast<llvm::Function>(CalleePtr); 5052 llvm::Module *M = Fn->getParent(); 5053 llvm::Function *Clone = M->getFunction(FDInlineName); 5054 if (!Clone) { 5055 Clone = llvm::Function::Create(Fn->getFunctionType(), 5056 llvm::GlobalValue::InternalLinkage, 5057 Fn->getAddressSpace(), FDInlineName, M); 5058 Clone->addFnAttr(llvm::Attribute::AlwaysInline); 5059 } 5060 return CGCallee::forDirect(Clone, GD); 5061 } 5062 5063 // Replaceable builtins provide their own implementation of a builtin. If we 5064 // are in an inline builtin implementation, avoid trivial infinite 5065 // recursion. Honor __attribute__((no_builtin("foo"))) or 5066 // __attribute__((no_builtin)) on the current function unless foo is 5067 // not a predefined library function which means we must generate the 5068 // builtin no matter what. 5069 else if (!IsPredefinedLibFunction || !HasAttributeNoBuiltin) 5070 return CGCallee::forBuiltin(builtinID, FD); 5071 } 5072 5073 llvm::Constant *CalleePtr = EmitFunctionDeclPointer(CGF.CGM, GD); 5074 if (CGF.CGM.getLangOpts().CUDA && !CGF.CGM.getLangOpts().CUDAIsDevice && 5075 FD->hasAttr<CUDAGlobalAttr>()) 5076 CalleePtr = CGF.CGM.getCUDARuntime().getKernelStub( 5077 cast<llvm::GlobalValue>(CalleePtr->stripPointerCasts())); 5078 5079 return CGCallee::forDirect(CalleePtr, GD); 5080 } 5081 5082 CGCallee CodeGenFunction::EmitCallee(const Expr *E) { 5083 E = E->IgnoreParens(); 5084 5085 // Look through function-to-pointer decay. 5086 if (auto ICE = dyn_cast<ImplicitCastExpr>(E)) { 5087 if (ICE->getCastKind() == CK_FunctionToPointerDecay || 5088 ICE->getCastKind() == CK_BuiltinFnToFnPtr) { 5089 return EmitCallee(ICE->getSubExpr()); 5090 } 5091 5092 // Resolve direct calls. 5093 } else if (auto DRE = dyn_cast<DeclRefExpr>(E)) { 5094 if (auto FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 5095 return EmitDirectCallee(*this, FD); 5096 } 5097 } else if (auto ME = dyn_cast<MemberExpr>(E)) { 5098 if (auto FD = dyn_cast<FunctionDecl>(ME->getMemberDecl())) { 5099 EmitIgnoredExpr(ME->getBase()); 5100 return EmitDirectCallee(*this, FD); 5101 } 5102 5103 // Look through template substitutions. 5104 } else if (auto NTTP = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) { 5105 return EmitCallee(NTTP->getReplacement()); 5106 5107 // Treat pseudo-destructor calls differently. 5108 } else if (auto PDE = dyn_cast<CXXPseudoDestructorExpr>(E)) { 5109 return CGCallee::forPseudoDestructor(PDE); 5110 } 5111 5112 // Otherwise, we have an indirect reference. 5113 llvm::Value *calleePtr; 5114 QualType functionType; 5115 if (auto ptrType = E->getType()->getAs<PointerType>()) { 5116 calleePtr = EmitScalarExpr(E); 5117 functionType = ptrType->getPointeeType(); 5118 } else { 5119 functionType = E->getType(); 5120 calleePtr = EmitLValue(E, KnownNonNull).getPointer(*this); 5121 } 5122 assert(functionType->isFunctionType()); 5123 5124 GlobalDecl GD; 5125 if (const auto *VD = 5126 dyn_cast_or_null<VarDecl>(E->getReferencedDeclOfCallee())) 5127 GD = GlobalDecl(VD); 5128 5129 CGCalleeInfo calleeInfo(functionType->getAs<FunctionProtoType>(), GD); 5130 CGCallee callee(calleeInfo, calleePtr); 5131 return callee; 5132 } 5133 5134 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) { 5135 // Comma expressions just emit their LHS then their RHS as an l-value. 5136 if (E->getOpcode() == BO_Comma) { 5137 EmitIgnoredExpr(E->getLHS()); 5138 EnsureInsertPoint(); 5139 return EmitLValue(E->getRHS()); 5140 } 5141 5142 if (E->getOpcode() == BO_PtrMemD || 5143 E->getOpcode() == BO_PtrMemI) 5144 return EmitPointerToDataMemberBinaryExpr(E); 5145 5146 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value"); 5147 5148 // Note that in all of these cases, __block variables need the RHS 5149 // evaluated first just in case the variable gets moved by the RHS. 5150 5151 switch (getEvaluationKind(E->getType())) { 5152 case TEK_Scalar: { 5153 switch (E->getLHS()->getType().getObjCLifetime()) { 5154 case Qualifiers::OCL_Strong: 5155 return EmitARCStoreStrong(E, /*ignored*/ false).first; 5156 5157 case Qualifiers::OCL_Autoreleasing: 5158 return EmitARCStoreAutoreleasing(E).first; 5159 5160 // No reason to do any of these differently. 5161 case Qualifiers::OCL_None: 5162 case Qualifiers::OCL_ExplicitNone: 5163 case Qualifiers::OCL_Weak: 5164 break; 5165 } 5166 5167 RValue RV = EmitAnyExpr(E->getRHS()); 5168 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store); 5169 if (RV.isScalar()) 5170 EmitNullabilityCheck(LV, RV.getScalarVal(), E->getExprLoc()); 5171 EmitStoreThroughLValue(RV, LV); 5172 if (getLangOpts().OpenMP) 5173 CGM.getOpenMPRuntime().checkAndEmitLastprivateConditional(*this, 5174 E->getLHS()); 5175 return LV; 5176 } 5177 5178 case TEK_Complex: 5179 return EmitComplexAssignmentLValue(E); 5180 5181 case TEK_Aggregate: 5182 return EmitAggExprToLValue(E); 5183 } 5184 llvm_unreachable("bad evaluation kind"); 5185 } 5186 5187 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) { 5188 RValue RV = EmitCallExpr(E); 5189 5190 if (!RV.isScalar()) 5191 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(), 5192 AlignmentSource::Decl); 5193 5194 assert(E->getCallReturnType(getContext())->isReferenceType() && 5195 "Can't have a scalar return unless the return type is a " 5196 "reference type!"); 5197 5198 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType()); 5199 } 5200 5201 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) { 5202 // FIXME: This shouldn't require another copy. 5203 return EmitAggExprToLValue(E); 5204 } 5205 5206 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) { 5207 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor() 5208 && "binding l-value to type which needs a temporary"); 5209 AggValueSlot Slot = CreateAggTemp(E->getType()); 5210 EmitCXXConstructExpr(E, Slot); 5211 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl); 5212 } 5213 5214 LValue 5215 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) { 5216 return MakeNaturalAlignAddrLValue(EmitCXXTypeidExpr(E), E->getType()); 5217 } 5218 5219 Address CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) { 5220 return CGM.GetAddrOfMSGuidDecl(E->getGuidDecl()) 5221 .withElementType(ConvertType(E->getType())); 5222 } 5223 5224 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) { 5225 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType(), 5226 AlignmentSource::Decl); 5227 } 5228 5229 LValue 5230 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) { 5231 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue"); 5232 Slot.setExternallyDestructed(); 5233 EmitAggExpr(E->getSubExpr(), Slot); 5234 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddress()); 5235 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl); 5236 } 5237 5238 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) { 5239 RValue RV = EmitObjCMessageExpr(E); 5240 5241 if (!RV.isScalar()) 5242 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(), 5243 AlignmentSource::Decl); 5244 5245 assert(E->getMethodDecl()->getReturnType()->isReferenceType() && 5246 "Can't have a scalar return unless the return type is a " 5247 "reference type!"); 5248 5249 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType()); 5250 } 5251 5252 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) { 5253 Address V = 5254 CGM.getObjCRuntime().GetAddrOfSelector(*this, E->getSelector()); 5255 return MakeAddrLValue(V, E->getType(), AlignmentSource::Decl); 5256 } 5257 5258 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface, 5259 const ObjCIvarDecl *Ivar) { 5260 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar); 5261 } 5262 5263 llvm::Value * 5264 CodeGenFunction::EmitIvarOffsetAsPointerDiff(const ObjCInterfaceDecl *Interface, 5265 const ObjCIvarDecl *Ivar) { 5266 llvm::Value *OffsetValue = EmitIvarOffset(Interface, Ivar); 5267 QualType PointerDiffType = getContext().getPointerDiffType(); 5268 return Builder.CreateZExtOrTrunc(OffsetValue, 5269 getTypes().ConvertType(PointerDiffType)); 5270 } 5271 5272 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy, 5273 llvm::Value *BaseValue, 5274 const ObjCIvarDecl *Ivar, 5275 unsigned CVRQualifiers) { 5276 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue, 5277 Ivar, CVRQualifiers); 5278 } 5279 5280 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) { 5281 // FIXME: A lot of the code below could be shared with EmitMemberExpr. 5282 llvm::Value *BaseValue = nullptr; 5283 const Expr *BaseExpr = E->getBase(); 5284 Qualifiers BaseQuals; 5285 QualType ObjectTy; 5286 if (E->isArrow()) { 5287 BaseValue = EmitScalarExpr(BaseExpr); 5288 ObjectTy = BaseExpr->getType()->getPointeeType(); 5289 BaseQuals = ObjectTy.getQualifiers(); 5290 } else { 5291 LValue BaseLV = EmitLValue(BaseExpr); 5292 BaseValue = BaseLV.getPointer(*this); 5293 ObjectTy = BaseExpr->getType(); 5294 BaseQuals = ObjectTy.getQualifiers(); 5295 } 5296 5297 LValue LV = 5298 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(), 5299 BaseQuals.getCVRQualifiers()); 5300 setObjCGCLValueClass(getContext(), E, LV); 5301 return LV; 5302 } 5303 5304 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) { 5305 // Can only get l-value for message expression returning aggregate type 5306 RValue RV = EmitAnyExprToTemp(E); 5307 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(), 5308 AlignmentSource::Decl); 5309 } 5310 5311 RValue CodeGenFunction::EmitCall(QualType CalleeType, const CGCallee &OrigCallee, 5312 const CallExpr *E, ReturnValueSlot ReturnValue, 5313 llvm::Value *Chain) { 5314 // Get the actual function type. The callee type will always be a pointer to 5315 // function type or a block pointer type. 5316 assert(CalleeType->isFunctionPointerType() && 5317 "Call must have function pointer type!"); 5318 5319 const Decl *TargetDecl = 5320 OrigCallee.getAbstractInfo().getCalleeDecl().getDecl(); 5321 5322 assert((!isa_and_present<FunctionDecl>(TargetDecl) || 5323 !cast<FunctionDecl>(TargetDecl)->isImmediateFunction()) && 5324 "trying to emit a call to an immediate function"); 5325 5326 CalleeType = getContext().getCanonicalType(CalleeType); 5327 5328 auto PointeeType = cast<PointerType>(CalleeType)->getPointeeType(); 5329 5330 CGCallee Callee = OrigCallee; 5331 5332 if (SanOpts.has(SanitizerKind::Function) && 5333 (!TargetDecl || !isa<FunctionDecl>(TargetDecl)) && 5334 !isa<FunctionNoProtoType>(PointeeType)) { 5335 if (llvm::Constant *PrefixSig = 5336 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) { 5337 SanitizerScope SanScope(this); 5338 auto *TypeHash = getUBSanFunctionTypeHash(PointeeType); 5339 5340 llvm::Type *PrefixSigType = PrefixSig->getType(); 5341 llvm::StructType *PrefixStructTy = llvm::StructType::get( 5342 CGM.getLLVMContext(), {PrefixSigType, Int32Ty}, /*isPacked=*/true); 5343 5344 llvm::Value *CalleePtr = Callee.getFunctionPointer(); 5345 5346 // On 32-bit Arm, the low bit of a function pointer indicates whether 5347 // it's using the Arm or Thumb instruction set. The actual first 5348 // instruction lives at the same address either way, so we must clear 5349 // that low bit before using the function address to find the prefix 5350 // structure. 5351 // 5352 // This applies to both Arm and Thumb target triples, because 5353 // either one could be used in an interworking context where it 5354 // might be passed function pointers of both types. 5355 llvm::Value *AlignedCalleePtr; 5356 if (CGM.getTriple().isARM() || CGM.getTriple().isThumb()) { 5357 llvm::Value *CalleeAddress = 5358 Builder.CreatePtrToInt(CalleePtr, IntPtrTy); 5359 llvm::Value *Mask = llvm::ConstantInt::get(IntPtrTy, ~1); 5360 llvm::Value *AlignedCalleeAddress = 5361 Builder.CreateAnd(CalleeAddress, Mask); 5362 AlignedCalleePtr = 5363 Builder.CreateIntToPtr(AlignedCalleeAddress, CalleePtr->getType()); 5364 } else { 5365 AlignedCalleePtr = CalleePtr; 5366 } 5367 5368 llvm::Value *CalleePrefixStruct = Builder.CreateBitCast( 5369 AlignedCalleePtr, llvm::PointerType::getUnqual(PrefixStructTy)); 5370 llvm::Value *CalleeSigPtr = 5371 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, -1, 0); 5372 llvm::Value *CalleeSig = 5373 Builder.CreateAlignedLoad(PrefixSigType, CalleeSigPtr, getIntAlign()); 5374 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig); 5375 5376 llvm::BasicBlock *Cont = createBasicBlock("cont"); 5377 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck"); 5378 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont); 5379 5380 EmitBlock(TypeCheck); 5381 llvm::Value *CalleeTypeHash = Builder.CreateAlignedLoad( 5382 Int32Ty, 5383 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, -1, 1), 5384 getPointerAlign()); 5385 llvm::Value *CalleeTypeHashMatch = 5386 Builder.CreateICmpEQ(CalleeTypeHash, TypeHash); 5387 llvm::Constant *StaticData[] = {EmitCheckSourceLocation(E->getBeginLoc()), 5388 EmitCheckTypeDescriptor(CalleeType)}; 5389 EmitCheck(std::make_pair(CalleeTypeHashMatch, SanitizerKind::Function), 5390 SanitizerHandler::FunctionTypeMismatch, StaticData, 5391 {CalleePtr}); 5392 5393 Builder.CreateBr(Cont); 5394 EmitBlock(Cont); 5395 } 5396 } 5397 5398 const auto *FnType = cast<FunctionType>(PointeeType); 5399 5400 // If we are checking indirect calls and this call is indirect, check that the 5401 // function pointer is a member of the bit set for the function type. 5402 if (SanOpts.has(SanitizerKind::CFIICall) && 5403 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) { 5404 SanitizerScope SanScope(this); 5405 EmitSanitizerStatReport(llvm::SanStat_CFI_ICall); 5406 5407 llvm::Metadata *MD; 5408 if (CGM.getCodeGenOpts().SanitizeCfiICallGeneralizePointers) 5409 MD = CGM.CreateMetadataIdentifierGeneralized(QualType(FnType, 0)); 5410 else 5411 MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0)); 5412 5413 llvm::Value *TypeId = llvm::MetadataAsValue::get(getLLVMContext(), MD); 5414 5415 llvm::Value *CalleePtr = Callee.getFunctionPointer(); 5416 llvm::Value *CastedCallee = Builder.CreateBitCast(CalleePtr, Int8PtrTy); 5417 llvm::Value *TypeTest = Builder.CreateCall( 5418 CGM.getIntrinsic(llvm::Intrinsic::type_test), {CastedCallee, TypeId}); 5419 5420 auto CrossDsoTypeId = CGM.CreateCrossDsoCfiTypeId(MD); 5421 llvm::Constant *StaticData[] = { 5422 llvm::ConstantInt::get(Int8Ty, CFITCK_ICall), 5423 EmitCheckSourceLocation(E->getBeginLoc()), 5424 EmitCheckTypeDescriptor(QualType(FnType, 0)), 5425 }; 5426 if (CGM.getCodeGenOpts().SanitizeCfiCrossDso && CrossDsoTypeId) { 5427 EmitCfiSlowPathCheck(SanitizerKind::CFIICall, TypeTest, CrossDsoTypeId, 5428 CastedCallee, StaticData); 5429 } else { 5430 EmitCheck(std::make_pair(TypeTest, SanitizerKind::CFIICall), 5431 SanitizerHandler::CFICheckFail, StaticData, 5432 {CastedCallee, llvm::UndefValue::get(IntPtrTy)}); 5433 } 5434 } 5435 5436 CallArgList Args; 5437 if (Chain) 5438 Args.add(RValue::get(Builder.CreateBitCast(Chain, CGM.VoidPtrTy)), 5439 CGM.getContext().VoidPtrTy); 5440 5441 // C++17 requires that we evaluate arguments to a call using assignment syntax 5442 // right-to-left, and that we evaluate arguments to certain other operators 5443 // left-to-right. Note that we allow this to override the order dictated by 5444 // the calling convention on the MS ABI, which means that parameter 5445 // destruction order is not necessarily reverse construction order. 5446 // FIXME: Revisit this based on C++ committee response to unimplementability. 5447 EvaluationOrder Order = EvaluationOrder::Default; 5448 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(E)) { 5449 if (OCE->isAssignmentOp()) 5450 Order = EvaluationOrder::ForceRightToLeft; 5451 else { 5452 switch (OCE->getOperator()) { 5453 case OO_LessLess: 5454 case OO_GreaterGreater: 5455 case OO_AmpAmp: 5456 case OO_PipePipe: 5457 case OO_Comma: 5458 case OO_ArrowStar: 5459 Order = EvaluationOrder::ForceLeftToRight; 5460 break; 5461 default: 5462 break; 5463 } 5464 } 5465 } 5466 5467 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), E->arguments(), 5468 E->getDirectCallee(), /*ParamsToSkip*/ 0, Order); 5469 5470 const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeFreeFunctionCall( 5471 Args, FnType, /*ChainCall=*/Chain); 5472 5473 // C99 6.5.2.2p6: 5474 // If the expression that denotes the called function has a type 5475 // that does not include a prototype, [the default argument 5476 // promotions are performed]. If the number of arguments does not 5477 // equal the number of parameters, the behavior is undefined. If 5478 // the function is defined with a type that includes a prototype, 5479 // and either the prototype ends with an ellipsis (, ...) or the 5480 // types of the arguments after promotion are not compatible with 5481 // the types of the parameters, the behavior is undefined. If the 5482 // function is defined with a type that does not include a 5483 // prototype, and the types of the arguments after promotion are 5484 // not compatible with those of the parameters after promotion, 5485 // the behavior is undefined [except in some trivial cases]. 5486 // That is, in the general case, we should assume that a call 5487 // through an unprototyped function type works like a *non-variadic* 5488 // call. The way we make this work is to cast to the exact type 5489 // of the promoted arguments. 5490 // 5491 // Chain calls use this same code path to add the invisible chain parameter 5492 // to the function type. 5493 if (isa<FunctionNoProtoType>(FnType) || Chain) { 5494 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo); 5495 int AS = Callee.getFunctionPointer()->getType()->getPointerAddressSpace(); 5496 CalleeTy = CalleeTy->getPointerTo(AS); 5497 5498 llvm::Value *CalleePtr = Callee.getFunctionPointer(); 5499 CalleePtr = Builder.CreateBitCast(CalleePtr, CalleeTy, "callee.knr.cast"); 5500 Callee.setFunctionPointer(CalleePtr); 5501 } 5502 5503 // HIP function pointer contains kernel handle when it is used in triple 5504 // chevron. The kernel stub needs to be loaded from kernel handle and used 5505 // as callee. 5506 if (CGM.getLangOpts().HIP && !CGM.getLangOpts().CUDAIsDevice && 5507 isa<CUDAKernelCallExpr>(E) && 5508 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) { 5509 llvm::Value *Handle = Callee.getFunctionPointer(); 5510 auto *Cast = 5511 Builder.CreateBitCast(Handle, Handle->getType()->getPointerTo()); 5512 auto *Stub = Builder.CreateLoad( 5513 Address(Cast, Handle->getType(), CGM.getPointerAlign())); 5514 Callee.setFunctionPointer(Stub); 5515 } 5516 llvm::CallBase *CallOrInvoke = nullptr; 5517 RValue Call = EmitCall(FnInfo, Callee, ReturnValue, Args, &CallOrInvoke, 5518 E == MustTailCall, E->getExprLoc()); 5519 5520 // Generate function declaration DISuprogram in order to be used 5521 // in debug info about call sites. 5522 if (CGDebugInfo *DI = getDebugInfo()) { 5523 if (auto *CalleeDecl = dyn_cast_or_null<FunctionDecl>(TargetDecl)) { 5524 FunctionArgList Args; 5525 QualType ResTy = BuildFunctionArgList(CalleeDecl, Args); 5526 DI->EmitFuncDeclForCallSite(CallOrInvoke, 5527 DI->getFunctionType(CalleeDecl, ResTy, Args), 5528 CalleeDecl); 5529 } 5530 } 5531 5532 return Call; 5533 } 5534 5535 LValue CodeGenFunction:: 5536 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) { 5537 Address BaseAddr = Address::invalid(); 5538 if (E->getOpcode() == BO_PtrMemI) { 5539 BaseAddr = EmitPointerWithAlignment(E->getLHS()); 5540 } else { 5541 BaseAddr = EmitLValue(E->getLHS()).getAddress(*this); 5542 } 5543 5544 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS()); 5545 const auto *MPT = E->getRHS()->getType()->castAs<MemberPointerType>(); 5546 5547 LValueBaseInfo BaseInfo; 5548 TBAAAccessInfo TBAAInfo; 5549 Address MemberAddr = 5550 EmitCXXMemberDataPointerAddress(E, BaseAddr, OffsetV, MPT, &BaseInfo, 5551 &TBAAInfo); 5552 5553 return MakeAddrLValue(MemberAddr, MPT->getPointeeType(), BaseInfo, TBAAInfo); 5554 } 5555 5556 /// Given the address of a temporary variable, produce an r-value of 5557 /// its type. 5558 RValue CodeGenFunction::convertTempToRValue(Address addr, 5559 QualType type, 5560 SourceLocation loc) { 5561 LValue lvalue = MakeAddrLValue(addr, type, AlignmentSource::Decl); 5562 switch (getEvaluationKind(type)) { 5563 case TEK_Complex: 5564 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc)); 5565 case TEK_Aggregate: 5566 return lvalue.asAggregateRValue(*this); 5567 case TEK_Scalar: 5568 return RValue::get(EmitLoadOfScalar(lvalue, loc)); 5569 } 5570 llvm_unreachable("bad evaluation kind"); 5571 } 5572 5573 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) { 5574 assert(Val->getType()->isFPOrFPVectorTy()); 5575 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val)) 5576 return; 5577 5578 llvm::MDBuilder MDHelper(getLLVMContext()); 5579 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy); 5580 5581 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node); 5582 } 5583 5584 void CodeGenFunction::SetSqrtFPAccuracy(llvm::Value *Val) { 5585 llvm::Type *EltTy = Val->getType()->getScalarType(); 5586 if (!EltTy->isFloatTy()) 5587 return; 5588 5589 if ((getLangOpts().OpenCL && 5590 !CGM.getCodeGenOpts().OpenCLCorrectlyRoundedDivSqrt) || 5591 (getLangOpts().HIP && getLangOpts().CUDAIsDevice && 5592 !CGM.getCodeGenOpts().HIPCorrectlyRoundedDivSqrt)) { 5593 // OpenCL v1.1 s7.4: minimum accuracy of single precision / is 3ulp 5594 // 5595 // OpenCL v1.2 s5.6.4.2: The -cl-fp32-correctly-rounded-divide-sqrt 5596 // build option allows an application to specify that single precision 5597 // floating-point divide (x/y and 1/x) and sqrt used in the program 5598 // source are correctly rounded. 5599 // 5600 // TODO: CUDA has a prec-sqrt flag 5601 SetFPAccuracy(Val, 3.0f); 5602 } 5603 } 5604 5605 void CodeGenFunction::SetDivFPAccuracy(llvm::Value *Val) { 5606 llvm::Type *EltTy = Val->getType()->getScalarType(); 5607 if (!EltTy->isFloatTy()) 5608 return; 5609 5610 if ((getLangOpts().OpenCL && 5611 !CGM.getCodeGenOpts().OpenCLCorrectlyRoundedDivSqrt) || 5612 (getLangOpts().HIP && getLangOpts().CUDAIsDevice && 5613 !CGM.getCodeGenOpts().HIPCorrectlyRoundedDivSqrt)) { 5614 // OpenCL v1.1 s7.4: minimum accuracy of single precision / is 2.5ulp 5615 // 5616 // OpenCL v1.2 s5.6.4.2: The -cl-fp32-correctly-rounded-divide-sqrt 5617 // build option allows an application to specify that single precision 5618 // floating-point divide (x/y and 1/x) and sqrt used in the program 5619 // source are correctly rounded. 5620 // 5621 // TODO: CUDA has a prec-div flag 5622 SetFPAccuracy(Val, 2.5f); 5623 } 5624 } 5625 5626 namespace { 5627 struct LValueOrRValue { 5628 LValue LV; 5629 RValue RV; 5630 }; 5631 } 5632 5633 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF, 5634 const PseudoObjectExpr *E, 5635 bool forLValue, 5636 AggValueSlot slot) { 5637 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques; 5638 5639 // Find the result expression, if any. 5640 const Expr *resultExpr = E->getResultExpr(); 5641 LValueOrRValue result; 5642 5643 for (PseudoObjectExpr::const_semantics_iterator 5644 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) { 5645 const Expr *semantic = *i; 5646 5647 // If this semantic expression is an opaque value, bind it 5648 // to the result of its source expression. 5649 if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) { 5650 // Skip unique OVEs. 5651 if (ov->isUnique()) { 5652 assert(ov != resultExpr && 5653 "A unique OVE cannot be used as the result expression"); 5654 continue; 5655 } 5656 5657 // If this is the result expression, we may need to evaluate 5658 // directly into the slot. 5659 typedef CodeGenFunction::OpaqueValueMappingData OVMA; 5660 OVMA opaqueData; 5661 if (ov == resultExpr && ov->isPRValue() && !forLValue && 5662 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) { 5663 CGF.EmitAggExpr(ov->getSourceExpr(), slot); 5664 LValue LV = CGF.MakeAddrLValue(slot.getAddress(), ov->getType(), 5665 AlignmentSource::Decl); 5666 opaqueData = OVMA::bind(CGF, ov, LV); 5667 result.RV = slot.asRValue(); 5668 5669 // Otherwise, emit as normal. 5670 } else { 5671 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr()); 5672 5673 // If this is the result, also evaluate the result now. 5674 if (ov == resultExpr) { 5675 if (forLValue) 5676 result.LV = CGF.EmitLValue(ov); 5677 else 5678 result.RV = CGF.EmitAnyExpr(ov, slot); 5679 } 5680 } 5681 5682 opaques.push_back(opaqueData); 5683 5684 // Otherwise, if the expression is the result, evaluate it 5685 // and remember the result. 5686 } else if (semantic == resultExpr) { 5687 if (forLValue) 5688 result.LV = CGF.EmitLValue(semantic); 5689 else 5690 result.RV = CGF.EmitAnyExpr(semantic, slot); 5691 5692 // Otherwise, evaluate the expression in an ignored context. 5693 } else { 5694 CGF.EmitIgnoredExpr(semantic); 5695 } 5696 } 5697 5698 // Unbind all the opaques now. 5699 for (unsigned i = 0, e = opaques.size(); i != e; ++i) 5700 opaques[i].unbind(CGF); 5701 5702 return result; 5703 } 5704 5705 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E, 5706 AggValueSlot slot) { 5707 return emitPseudoObjectExpr(*this, E, false, slot).RV; 5708 } 5709 5710 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) { 5711 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV; 5712 } 5713