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 "ABIInfoImpl.h" 14 #include "CGCUDARuntime.h" 15 #include "CGCXXABI.h" 16 #include "CGCall.h" 17 #include "CGCleanup.h" 18 #include "CGDebugInfo.h" 19 #include "CGObjCRuntime.h" 20 #include "CGOpenMPRuntime.h" 21 #include "CGRecordLayout.h" 22 #include "CodeGenFunction.h" 23 #include "CodeGenModule.h" 24 #include "ConstantEmitter.h" 25 #include "TargetInfo.h" 26 #include "clang/AST/ASTContext.h" 27 #include "clang/AST/Attr.h" 28 #include "clang/AST/DeclObjC.h" 29 #include "clang/AST/NSAPI.h" 30 #include "clang/AST/StmtVisitor.h" 31 #include "clang/Basic/Builtins.h" 32 #include "clang/Basic/CodeGenOptions.h" 33 #include "clang/Basic/SourceManager.h" 34 #include "llvm/ADT/Hashing.h" 35 #include "llvm/ADT/STLExtras.h" 36 #include "llvm/ADT/StringExtras.h" 37 #include "llvm/IR/DataLayout.h" 38 #include "llvm/IR/Intrinsics.h" 39 #include "llvm/IR/IntrinsicsWebAssembly.h" 40 #include "llvm/IR/LLVMContext.h" 41 #include "llvm/IR/MDBuilder.h" 42 #include "llvm/IR/MatrixBuilder.h" 43 #include "llvm/Passes/OptimizationLevel.h" 44 #include "llvm/Support/ConvertUTF.h" 45 #include "llvm/Support/MathExtras.h" 46 #include "llvm/Support/Path.h" 47 #include "llvm/Support/SaveAndRestore.h" 48 #include "llvm/Support/xxhash.h" 49 #include "llvm/Transforms/Utils/SanitizerStats.h" 50 51 #include <optional> 52 #include <string> 53 54 using namespace clang; 55 using namespace CodeGen; 56 57 // Experiment to make sanitizers easier to debug 58 static llvm::cl::opt<bool> ClSanitizeDebugDeoptimization( 59 "ubsan-unique-traps", llvm::cl::Optional, 60 llvm::cl::desc("Deoptimize traps for UBSAN so there is 1 trap per check.")); 61 62 // TODO: Introduce frontend options to enabled per sanitizers, similar to 63 // `fsanitize-trap`. 64 static llvm::cl::opt<bool> ClSanitizeGuardChecks( 65 "ubsan-guard-checks", llvm::cl::Optional, 66 llvm::cl::desc("Guard UBSAN checks with `llvm.allow.ubsan.check()`.")); 67 68 //===--------------------------------------------------------------------===// 69 // Miscellaneous Helper Methods 70 //===--------------------------------------------------------------------===// 71 72 /// CreateTempAlloca - This creates a alloca and inserts it into the entry 73 /// block. 74 RawAddress 75 CodeGenFunction::CreateTempAllocaWithoutCast(llvm::Type *Ty, CharUnits Align, 76 const Twine &Name, 77 llvm::Value *ArraySize) { 78 auto Alloca = CreateTempAlloca(Ty, Name, ArraySize); 79 Alloca->setAlignment(Align.getAsAlign()); 80 return RawAddress(Alloca, Ty, Align, KnownNonNull); 81 } 82 83 /// CreateTempAlloca - This creates a alloca and inserts it into the entry 84 /// block. The alloca is casted to default address space if necessary. 85 RawAddress CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, CharUnits Align, 86 const Twine &Name, 87 llvm::Value *ArraySize, 88 RawAddress *AllocaAddr) { 89 auto Alloca = CreateTempAllocaWithoutCast(Ty, Align, Name, ArraySize); 90 if (AllocaAddr) 91 *AllocaAddr = Alloca; 92 llvm::Value *V = Alloca.getPointer(); 93 // Alloca always returns a pointer in alloca address space, which may 94 // be different from the type defined by the language. For example, 95 // in C++ the auto variables are in the default address space. Therefore 96 // cast alloca to the default address space when necessary. 97 if (getASTAllocaAddressSpace() != LangAS::Default) { 98 auto DestAddrSpace = getContext().getTargetAddressSpace(LangAS::Default); 99 llvm::IRBuilderBase::InsertPointGuard IPG(Builder); 100 // When ArraySize is nullptr, alloca is inserted at AllocaInsertPt, 101 // otherwise alloca is inserted at the current insertion point of the 102 // builder. 103 if (!ArraySize) 104 Builder.SetInsertPoint(getPostAllocaInsertPoint()); 105 V = getTargetHooks().performAddrSpaceCast( 106 *this, V, getASTAllocaAddressSpace(), LangAS::Default, 107 Ty->getPointerTo(DestAddrSpace), /*non-null*/ true); 108 } 109 110 return RawAddress(V, Ty, Align, KnownNonNull); 111 } 112 113 /// CreateTempAlloca - This creates an alloca and inserts it into the entry 114 /// block if \p ArraySize is nullptr, otherwise inserts it at the current 115 /// insertion point of the builder. 116 llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, 117 const Twine &Name, 118 llvm::Value *ArraySize) { 119 llvm::AllocaInst *Alloca; 120 if (ArraySize) 121 Alloca = Builder.CreateAlloca(Ty, ArraySize, Name); 122 else 123 Alloca = new llvm::AllocaInst(Ty, CGM.getDataLayout().getAllocaAddrSpace(), 124 ArraySize, Name, &*AllocaInsertPt); 125 if (Allocas) { 126 Allocas->Add(Alloca); 127 } 128 return Alloca; 129 } 130 131 /// CreateDefaultAlignTempAlloca - This creates an alloca with the 132 /// default alignment of the corresponding LLVM type, which is *not* 133 /// guaranteed to be related in any way to the expected alignment of 134 /// an AST type that might have been lowered to Ty. 135 RawAddress CodeGenFunction::CreateDefaultAlignTempAlloca(llvm::Type *Ty, 136 const Twine &Name) { 137 CharUnits Align = 138 CharUnits::fromQuantity(CGM.getDataLayout().getPrefTypeAlign(Ty)); 139 return CreateTempAlloca(Ty, Align, Name); 140 } 141 142 RawAddress CodeGenFunction::CreateIRTemp(QualType Ty, const Twine &Name) { 143 CharUnits Align = getContext().getTypeAlignInChars(Ty); 144 return CreateTempAlloca(ConvertType(Ty), Align, Name); 145 } 146 147 RawAddress CodeGenFunction::CreateMemTemp(QualType Ty, const Twine &Name, 148 RawAddress *Alloca) { 149 // FIXME: Should we prefer the preferred type alignment here? 150 return CreateMemTemp(Ty, getContext().getTypeAlignInChars(Ty), Name, Alloca); 151 } 152 153 RawAddress CodeGenFunction::CreateMemTemp(QualType Ty, CharUnits Align, 154 const Twine &Name, 155 RawAddress *Alloca) { 156 RawAddress Result = CreateTempAlloca(ConvertTypeForMem(Ty), Align, Name, 157 /*ArraySize=*/nullptr, Alloca); 158 159 if (Ty->isConstantMatrixType()) { 160 auto *ArrayTy = cast<llvm::ArrayType>(Result.getElementType()); 161 auto *VectorTy = llvm::FixedVectorType::get(ArrayTy->getElementType(), 162 ArrayTy->getNumElements()); 163 164 Result = Address(Result.getPointer(), VectorTy, Result.getAlignment(), 165 KnownNonNull); 166 } 167 return Result; 168 } 169 170 RawAddress CodeGenFunction::CreateMemTempWithoutCast(QualType Ty, 171 CharUnits Align, 172 const Twine &Name) { 173 return CreateTempAllocaWithoutCast(ConvertTypeForMem(Ty), Align, Name); 174 } 175 176 RawAddress CodeGenFunction::CreateMemTempWithoutCast(QualType Ty, 177 const Twine &Name) { 178 return CreateMemTempWithoutCast(Ty, getContext().getTypeAlignInChars(Ty), 179 Name); 180 } 181 182 /// EvaluateExprAsBool - Perform the usual unary conversions on the specified 183 /// expression and compare the result against zero, returning an Int1Ty value. 184 llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) { 185 PGO.setCurrentStmt(E); 186 if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) { 187 llvm::Value *MemPtr = EmitScalarExpr(E); 188 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT); 189 } 190 191 QualType BoolTy = getContext().BoolTy; 192 SourceLocation Loc = E->getExprLoc(); 193 CGFPOptionsRAII FPOptsRAII(*this, E); 194 if (!E->getType()->isAnyComplexType()) 195 return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy, Loc); 196 197 return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(), BoolTy, 198 Loc); 199 } 200 201 /// EmitIgnoredExpr - Emit code to compute the specified expression, 202 /// ignoring the result. 203 void CodeGenFunction::EmitIgnoredExpr(const Expr *E) { 204 if (E->isPRValue()) 205 return (void)EmitAnyExpr(E, AggValueSlot::ignored(), true); 206 207 // if this is a bitfield-resulting conditional operator, we can special case 208 // emit this. The normal 'EmitLValue' version of this is particularly 209 // difficult to codegen for, since creating a single "LValue" for two 210 // different sized arguments here is not particularly doable. 211 if (const auto *CondOp = dyn_cast<AbstractConditionalOperator>( 212 E->IgnoreParenNoopCasts(getContext()))) { 213 if (CondOp->getObjectKind() == OK_BitField) 214 return EmitIgnoredConditionalOperator(CondOp); 215 } 216 217 // Just emit it as an l-value and drop the result. 218 EmitLValue(E); 219 } 220 221 /// EmitAnyExpr - Emit code to compute the specified expression which 222 /// can have any type. The result is returned as an RValue struct. 223 /// If this is an aggregate expression, AggSlot indicates where the 224 /// result should be returned. 225 RValue CodeGenFunction::EmitAnyExpr(const Expr *E, 226 AggValueSlot aggSlot, 227 bool ignoreResult) { 228 switch (getEvaluationKind(E->getType())) { 229 case TEK_Scalar: 230 return RValue::get(EmitScalarExpr(E, ignoreResult)); 231 case TEK_Complex: 232 return RValue::getComplex(EmitComplexExpr(E, ignoreResult, ignoreResult)); 233 case TEK_Aggregate: 234 if (!ignoreResult && aggSlot.isIgnored()) 235 aggSlot = CreateAggTemp(E->getType(), "agg-temp"); 236 EmitAggExpr(E, aggSlot); 237 return aggSlot.asRValue(); 238 } 239 llvm_unreachable("bad evaluation kind"); 240 } 241 242 /// EmitAnyExprToTemp - Similar to EmitAnyExpr(), however, the result will 243 /// always be accessible even if no aggregate location is provided. 244 RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) { 245 AggValueSlot AggSlot = AggValueSlot::ignored(); 246 247 if (hasAggregateEvaluationKind(E->getType())) 248 AggSlot = CreateAggTemp(E->getType(), "agg.tmp"); 249 return EmitAnyExpr(E, AggSlot); 250 } 251 252 /// EmitAnyExprToMem - Evaluate an expression into a given memory 253 /// location. 254 void CodeGenFunction::EmitAnyExprToMem(const Expr *E, 255 Address Location, 256 Qualifiers Quals, 257 bool IsInit) { 258 // FIXME: This function should take an LValue as an argument. 259 switch (getEvaluationKind(E->getType())) { 260 case TEK_Complex: 261 EmitComplexExprIntoLValue(E, MakeAddrLValue(Location, E->getType()), 262 /*isInit*/ false); 263 return; 264 265 case TEK_Aggregate: { 266 EmitAggExpr(E, AggValueSlot::forAddr(Location, Quals, 267 AggValueSlot::IsDestructed_t(IsInit), 268 AggValueSlot::DoesNotNeedGCBarriers, 269 AggValueSlot::IsAliased_t(!IsInit), 270 AggValueSlot::MayOverlap)); 271 return; 272 } 273 274 case TEK_Scalar: { 275 RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false)); 276 LValue LV = MakeAddrLValue(Location, E->getType()); 277 EmitStoreThroughLValue(RV, LV); 278 return; 279 } 280 } 281 llvm_unreachable("bad evaluation kind"); 282 } 283 284 static void 285 pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M, 286 const Expr *E, Address ReferenceTemporary) { 287 // Objective-C++ ARC: 288 // If we are binding a reference to a temporary that has ownership, we 289 // need to perform retain/release operations on the temporary. 290 // 291 // FIXME: This should be looking at E, not M. 292 if (auto Lifetime = M->getType().getObjCLifetime()) { 293 switch (Lifetime) { 294 case Qualifiers::OCL_None: 295 case Qualifiers::OCL_ExplicitNone: 296 // Carry on to normal cleanup handling. 297 break; 298 299 case Qualifiers::OCL_Autoreleasing: 300 // Nothing to do; cleaned up by an autorelease pool. 301 return; 302 303 case Qualifiers::OCL_Strong: 304 case Qualifiers::OCL_Weak: 305 switch (StorageDuration Duration = M->getStorageDuration()) { 306 case SD_Static: 307 // Note: we intentionally do not register a cleanup to release 308 // the object on program termination. 309 return; 310 311 case SD_Thread: 312 // FIXME: We should probably register a cleanup in this case. 313 return; 314 315 case SD_Automatic: 316 case SD_FullExpression: 317 CodeGenFunction::Destroyer *Destroy; 318 CleanupKind CleanupKind; 319 if (Lifetime == Qualifiers::OCL_Strong) { 320 const ValueDecl *VD = M->getExtendingDecl(); 321 bool Precise = isa_and_nonnull<VarDecl>(VD) && 322 VD->hasAttr<ObjCPreciseLifetimeAttr>(); 323 CleanupKind = CGF.getARCCleanupKind(); 324 Destroy = Precise ? &CodeGenFunction::destroyARCStrongPrecise 325 : &CodeGenFunction::destroyARCStrongImprecise; 326 } else { 327 // __weak objects always get EH cleanups; otherwise, exceptions 328 // could cause really nasty crashes instead of mere leaks. 329 CleanupKind = NormalAndEHCleanup; 330 Destroy = &CodeGenFunction::destroyARCWeak; 331 } 332 if (Duration == SD_FullExpression) 333 CGF.pushDestroy(CleanupKind, ReferenceTemporary, 334 M->getType(), *Destroy, 335 CleanupKind & EHCleanup); 336 else 337 CGF.pushLifetimeExtendedDestroy(CleanupKind, ReferenceTemporary, 338 M->getType(), 339 *Destroy, CleanupKind & EHCleanup); 340 return; 341 342 case SD_Dynamic: 343 llvm_unreachable("temporary cannot have dynamic storage duration"); 344 } 345 llvm_unreachable("unknown storage duration"); 346 } 347 } 348 349 CXXDestructorDecl *ReferenceTemporaryDtor = nullptr; 350 if (const RecordType *RT = 351 E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) { 352 // Get the destructor for the reference temporary. 353 auto *ClassDecl = cast<CXXRecordDecl>(RT->getDecl()); 354 if (!ClassDecl->hasTrivialDestructor()) 355 ReferenceTemporaryDtor = ClassDecl->getDestructor(); 356 } 357 358 if (!ReferenceTemporaryDtor) 359 return; 360 361 // Call the destructor for the temporary. 362 switch (M->getStorageDuration()) { 363 case SD_Static: 364 case SD_Thread: { 365 llvm::FunctionCallee CleanupFn; 366 llvm::Constant *CleanupArg; 367 if (E->getType()->isArrayType()) { 368 CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper( 369 ReferenceTemporary, E->getType(), 370 CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions, 371 dyn_cast_or_null<VarDecl>(M->getExtendingDecl())); 372 CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy); 373 } else { 374 CleanupFn = CGF.CGM.getAddrAndTypeOfCXXStructor( 375 GlobalDecl(ReferenceTemporaryDtor, Dtor_Complete)); 376 CleanupArg = cast<llvm::Constant>(ReferenceTemporary.emitRawPointer(CGF)); 377 } 378 CGF.CGM.getCXXABI().registerGlobalDtor( 379 CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg); 380 break; 381 } 382 383 case SD_FullExpression: 384 CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(), 385 CodeGenFunction::destroyCXXObject, 386 CGF.getLangOpts().Exceptions); 387 break; 388 389 case SD_Automatic: 390 CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup, 391 ReferenceTemporary, E->getType(), 392 CodeGenFunction::destroyCXXObject, 393 CGF.getLangOpts().Exceptions); 394 break; 395 396 case SD_Dynamic: 397 llvm_unreachable("temporary cannot have dynamic storage duration"); 398 } 399 } 400 401 static RawAddress createReferenceTemporary(CodeGenFunction &CGF, 402 const MaterializeTemporaryExpr *M, 403 const Expr *Inner, 404 RawAddress *Alloca = nullptr) { 405 auto &TCG = CGF.getTargetHooks(); 406 switch (M->getStorageDuration()) { 407 case SD_FullExpression: 408 case SD_Automatic: { 409 // If we have a constant temporary array or record try to promote it into a 410 // constant global under the same rules a normal constant would've been 411 // promoted. This is easier on the optimizer and generally emits fewer 412 // instructions. 413 QualType Ty = Inner->getType(); 414 if (CGF.CGM.getCodeGenOpts().MergeAllConstants && 415 (Ty->isArrayType() || Ty->isRecordType()) && 416 Ty.isConstantStorage(CGF.getContext(), true, false)) 417 if (auto Init = ConstantEmitter(CGF).tryEmitAbstract(Inner, Ty)) { 418 auto AS = CGF.CGM.GetGlobalConstantAddressSpace(); 419 auto *GV = new llvm::GlobalVariable( 420 CGF.CGM.getModule(), Init->getType(), /*isConstant=*/true, 421 llvm::GlobalValue::PrivateLinkage, Init, ".ref.tmp", nullptr, 422 llvm::GlobalValue::NotThreadLocal, 423 CGF.getContext().getTargetAddressSpace(AS)); 424 CharUnits alignment = CGF.getContext().getTypeAlignInChars(Ty); 425 GV->setAlignment(alignment.getAsAlign()); 426 llvm::Constant *C = GV; 427 if (AS != LangAS::Default) 428 C = TCG.performAddrSpaceCast( 429 CGF.CGM, GV, AS, LangAS::Default, 430 GV->getValueType()->getPointerTo( 431 CGF.getContext().getTargetAddressSpace(LangAS::Default))); 432 // FIXME: Should we put the new global into a COMDAT? 433 return RawAddress(C, GV->getValueType(), alignment); 434 } 435 return CGF.CreateMemTemp(Ty, "ref.tmp", Alloca); 436 } 437 case SD_Thread: 438 case SD_Static: 439 return CGF.CGM.GetAddrOfGlobalTemporary(M, Inner); 440 441 case SD_Dynamic: 442 llvm_unreachable("temporary can't have dynamic storage duration"); 443 } 444 llvm_unreachable("unknown storage duration"); 445 } 446 447 /// Helper method to check if the underlying ABI is AAPCS 448 static bool isAAPCS(const TargetInfo &TargetInfo) { 449 return TargetInfo.getABI().starts_with("aapcs"); 450 } 451 452 LValue CodeGenFunction:: 453 EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) { 454 const Expr *E = M->getSubExpr(); 455 456 assert((!M->getExtendingDecl() || !isa<VarDecl>(M->getExtendingDecl()) || 457 !cast<VarDecl>(M->getExtendingDecl())->isARCPseudoStrong()) && 458 "Reference should never be pseudo-strong!"); 459 460 // FIXME: ideally this would use EmitAnyExprToMem, however, we cannot do so 461 // as that will cause the lifetime adjustment to be lost for ARC 462 auto ownership = M->getType().getObjCLifetime(); 463 if (ownership != Qualifiers::OCL_None && 464 ownership != Qualifiers::OCL_ExplicitNone) { 465 RawAddress Object = createReferenceTemporary(*this, M, E); 466 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) { 467 llvm::Type *Ty = ConvertTypeForMem(E->getType()); 468 Object = Object.withElementType(Ty); 469 470 // createReferenceTemporary will promote the temporary to a global with a 471 // constant initializer if it can. It can only do this to a value of 472 // ARC-manageable type if the value is global and therefore "immune" to 473 // ref-counting operations. Therefore we have no need to emit either a 474 // dynamic initialization or a cleanup and we can just return the address 475 // of the temporary. 476 if (Var->hasInitializer()) 477 return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl); 478 479 Var->setInitializer(CGM.EmitNullConstant(E->getType())); 480 } 481 LValue RefTempDst = MakeAddrLValue(Object, M->getType(), 482 AlignmentSource::Decl); 483 484 switch (getEvaluationKind(E->getType())) { 485 default: llvm_unreachable("expected scalar or aggregate expression"); 486 case TEK_Scalar: 487 EmitScalarInit(E, M->getExtendingDecl(), RefTempDst, false); 488 break; 489 case TEK_Aggregate: { 490 EmitAggExpr(E, AggValueSlot::forAddr(Object, 491 E->getType().getQualifiers(), 492 AggValueSlot::IsDestructed, 493 AggValueSlot::DoesNotNeedGCBarriers, 494 AggValueSlot::IsNotAliased, 495 AggValueSlot::DoesNotOverlap)); 496 break; 497 } 498 } 499 500 pushTemporaryCleanup(*this, M, E, Object); 501 return RefTempDst; 502 } 503 504 SmallVector<const Expr *, 2> CommaLHSs; 505 SmallVector<SubobjectAdjustment, 2> Adjustments; 506 E = E->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments); 507 508 for (const auto &Ignored : CommaLHSs) 509 EmitIgnoredExpr(Ignored); 510 511 if (const auto *opaque = dyn_cast<OpaqueValueExpr>(E)) { 512 if (opaque->getType()->isRecordType()) { 513 assert(Adjustments.empty()); 514 return EmitOpaqueValueLValue(opaque); 515 } 516 } 517 518 // Create and initialize the reference temporary. 519 RawAddress Alloca = Address::invalid(); 520 RawAddress Object = createReferenceTemporary(*this, M, E, &Alloca); 521 if (auto *Var = dyn_cast<llvm::GlobalVariable>( 522 Object.getPointer()->stripPointerCasts())) { 523 llvm::Type *TemporaryType = ConvertTypeForMem(E->getType()); 524 Object = Object.withElementType(TemporaryType); 525 // If the temporary is a global and has a constant initializer or is a 526 // constant temporary that we promoted to a global, we may have already 527 // initialized it. 528 if (!Var->hasInitializer()) { 529 Var->setInitializer(CGM.EmitNullConstant(E->getType())); 530 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true); 531 } 532 } else { 533 switch (M->getStorageDuration()) { 534 case SD_Automatic: 535 if (auto *Size = EmitLifetimeStart( 536 CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()), 537 Alloca.getPointer())) { 538 pushCleanupAfterFullExpr<CallLifetimeEnd>(NormalEHLifetimeMarker, 539 Alloca, Size); 540 } 541 break; 542 543 case SD_FullExpression: { 544 if (!ShouldEmitLifetimeMarkers) 545 break; 546 547 // Avoid creating a conditional cleanup just to hold an llvm.lifetime.end 548 // marker. Instead, start the lifetime of a conditional temporary earlier 549 // so that it's unconditional. Don't do this with sanitizers which need 550 // more precise lifetime marks. However when inside an "await.suspend" 551 // block, we should always avoid conditional cleanup because it creates 552 // boolean marker that lives across await_suspend, which can destroy coro 553 // frame. 554 ConditionalEvaluation *OldConditional = nullptr; 555 CGBuilderTy::InsertPoint OldIP; 556 if (isInConditionalBranch() && !E->getType().isDestructedType() && 557 ((!SanOpts.has(SanitizerKind::HWAddress) && 558 !SanOpts.has(SanitizerKind::Memory) && 559 !CGM.getCodeGenOpts().SanitizeAddressUseAfterScope) || 560 inSuspendBlock())) { 561 OldConditional = OutermostConditional; 562 OutermostConditional = nullptr; 563 564 OldIP = Builder.saveIP(); 565 llvm::BasicBlock *Block = OldConditional->getStartingBlock(); 566 Builder.restoreIP(CGBuilderTy::InsertPoint( 567 Block, llvm::BasicBlock::iterator(Block->back()))); 568 } 569 570 if (auto *Size = EmitLifetimeStart( 571 CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()), 572 Alloca.getPointer())) { 573 pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Alloca, 574 Size); 575 } 576 577 if (OldConditional) { 578 OutermostConditional = OldConditional; 579 Builder.restoreIP(OldIP); 580 } 581 break; 582 } 583 584 default: 585 break; 586 } 587 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true); 588 } 589 pushTemporaryCleanup(*this, M, E, Object); 590 591 // Perform derived-to-base casts and/or field accesses, to get from the 592 // temporary object we created (and, potentially, for which we extended 593 // the lifetime) to the subobject we're binding the reference to. 594 for (SubobjectAdjustment &Adjustment : llvm::reverse(Adjustments)) { 595 switch (Adjustment.Kind) { 596 case SubobjectAdjustment::DerivedToBaseAdjustment: 597 Object = 598 GetAddressOfBaseClass(Object, Adjustment.DerivedToBase.DerivedClass, 599 Adjustment.DerivedToBase.BasePath->path_begin(), 600 Adjustment.DerivedToBase.BasePath->path_end(), 601 /*NullCheckValue=*/ false, E->getExprLoc()); 602 break; 603 604 case SubobjectAdjustment::FieldAdjustment: { 605 LValue LV = MakeAddrLValue(Object, E->getType(), AlignmentSource::Decl); 606 LV = EmitLValueForField(LV, Adjustment.Field); 607 assert(LV.isSimple() && 608 "materialized temporary field is not a simple lvalue"); 609 Object = LV.getAddress(); 610 break; 611 } 612 613 case SubobjectAdjustment::MemberPointerAdjustment: { 614 llvm::Value *Ptr = EmitScalarExpr(Adjustment.Ptr.RHS); 615 Object = EmitCXXMemberDataPointerAddress(E, Object, Ptr, 616 Adjustment.Ptr.MPT); 617 break; 618 } 619 } 620 } 621 622 return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl); 623 } 624 625 RValue 626 CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E) { 627 // Emit the expression as an lvalue. 628 LValue LV = EmitLValue(E); 629 assert(LV.isSimple()); 630 llvm::Value *Value = LV.getPointer(*this); 631 632 if (sanitizePerformTypeCheck() && !E->getType()->isFunctionType()) { 633 // C++11 [dcl.ref]p5 (as amended by core issue 453): 634 // If a glvalue to which a reference is directly bound designates neither 635 // an existing object or function of an appropriate type nor a region of 636 // storage of suitable size and alignment to contain an object of the 637 // reference's type, the behavior is undefined. 638 QualType Ty = E->getType(); 639 EmitTypeCheck(TCK_ReferenceBinding, E->getExprLoc(), Value, Ty); 640 } 641 642 return RValue::get(Value); 643 } 644 645 646 /// getAccessedFieldNo - Given an encoded value and a result number, return the 647 /// input field number being accessed. 648 unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx, 649 const llvm::Constant *Elts) { 650 return cast<llvm::ConstantInt>(Elts->getAggregateElement(Idx)) 651 ->getZExtValue(); 652 } 653 654 static llvm::Value *emitHashMix(CGBuilderTy &Builder, llvm::Value *Acc, 655 llvm::Value *Ptr) { 656 llvm::Value *A0 = 657 Builder.CreateMul(Ptr, Builder.getInt64(0xbf58476d1ce4e5b9u)); 658 llvm::Value *A1 = 659 Builder.CreateXor(A0, Builder.CreateLShr(A0, Builder.getInt64(31))); 660 return Builder.CreateXor(Acc, A1); 661 } 662 663 bool CodeGenFunction::isNullPointerAllowed(TypeCheckKind TCK) { 664 return TCK == TCK_DowncastPointer || TCK == TCK_Upcast || 665 TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation; 666 } 667 668 bool CodeGenFunction::isVptrCheckRequired(TypeCheckKind TCK, QualType Ty) { 669 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl(); 670 return (RD && RD->hasDefinition() && RD->isDynamicClass()) && 671 (TCK == TCK_MemberAccess || TCK == TCK_MemberCall || 672 TCK == TCK_DowncastPointer || TCK == TCK_DowncastReference || 673 TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation); 674 } 675 676 bool CodeGenFunction::sanitizePerformTypeCheck() const { 677 return SanOpts.has(SanitizerKind::Null) || 678 SanOpts.has(SanitizerKind::Alignment) || 679 SanOpts.has(SanitizerKind::ObjectSize) || 680 SanOpts.has(SanitizerKind::Vptr); 681 } 682 683 void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc, 684 llvm::Value *Ptr, QualType Ty, 685 CharUnits Alignment, 686 SanitizerSet SkippedChecks, 687 llvm::Value *ArraySize) { 688 if (!sanitizePerformTypeCheck()) 689 return; 690 691 // Don't check pointers outside the default address space. The null check 692 // isn't correct, the object-size check isn't supported by LLVM, and we can't 693 // communicate the addresses to the runtime handler for the vptr check. 694 if (Ptr->getType()->getPointerAddressSpace()) 695 return; 696 697 // Don't check pointers to volatile data. The behavior here is implementation- 698 // defined. 699 if (Ty.isVolatileQualified()) 700 return; 701 702 SanitizerScope SanScope(this); 703 704 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 3> Checks; 705 llvm::BasicBlock *Done = nullptr; 706 707 // Quickly determine whether we have a pointer to an alloca. It's possible 708 // to skip null checks, and some alignment checks, for these pointers. This 709 // can reduce compile-time significantly. 710 auto PtrToAlloca = dyn_cast<llvm::AllocaInst>(Ptr->stripPointerCasts()); 711 712 llvm::Value *True = llvm::ConstantInt::getTrue(getLLVMContext()); 713 llvm::Value *IsNonNull = nullptr; 714 bool IsGuaranteedNonNull = 715 SkippedChecks.has(SanitizerKind::Null) || PtrToAlloca; 716 bool AllowNullPointers = isNullPointerAllowed(TCK); 717 if ((SanOpts.has(SanitizerKind::Null) || AllowNullPointers) && 718 !IsGuaranteedNonNull) { 719 // The glvalue must not be an empty glvalue. 720 IsNonNull = Builder.CreateIsNotNull(Ptr); 721 722 // The IR builder can constant-fold the null check if the pointer points to 723 // a constant. 724 IsGuaranteedNonNull = IsNonNull == True; 725 726 // Skip the null check if the pointer is known to be non-null. 727 if (!IsGuaranteedNonNull) { 728 if (AllowNullPointers) { 729 // When performing pointer casts, it's OK if the value is null. 730 // Skip the remaining checks in that case. 731 Done = createBasicBlock("null"); 732 llvm::BasicBlock *Rest = createBasicBlock("not.null"); 733 Builder.CreateCondBr(IsNonNull, Rest, Done); 734 EmitBlock(Rest); 735 } else { 736 Checks.push_back(std::make_pair(IsNonNull, SanitizerKind::Null)); 737 } 738 } 739 } 740 741 if (SanOpts.has(SanitizerKind::ObjectSize) && 742 !SkippedChecks.has(SanitizerKind::ObjectSize) && 743 !Ty->isIncompleteType()) { 744 uint64_t TySize = CGM.getMinimumObjectSize(Ty).getQuantity(); 745 llvm::Value *Size = llvm::ConstantInt::get(IntPtrTy, TySize); 746 if (ArraySize) 747 Size = Builder.CreateMul(Size, ArraySize); 748 749 // Degenerate case: new X[0] does not need an objectsize check. 750 llvm::Constant *ConstantSize = dyn_cast<llvm::Constant>(Size); 751 if (!ConstantSize || !ConstantSize->isNullValue()) { 752 // The glvalue must refer to a large enough storage region. 753 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation 754 // to check this. 755 // FIXME: Get object address space 756 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy }; 757 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys); 758 llvm::Value *Min = Builder.getFalse(); 759 llvm::Value *NullIsUnknown = Builder.getFalse(); 760 llvm::Value *Dynamic = Builder.getFalse(); 761 llvm::Value *LargeEnough = Builder.CreateICmpUGE( 762 Builder.CreateCall(F, {Ptr, Min, NullIsUnknown, Dynamic}), Size); 763 Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize)); 764 } 765 } 766 767 llvm::MaybeAlign AlignVal; 768 llvm::Value *PtrAsInt = nullptr; 769 770 if (SanOpts.has(SanitizerKind::Alignment) && 771 !SkippedChecks.has(SanitizerKind::Alignment)) { 772 AlignVal = Alignment.getAsMaybeAlign(); 773 if (!Ty->isIncompleteType() && !AlignVal) 774 AlignVal = CGM.getNaturalTypeAlignment(Ty, nullptr, nullptr, 775 /*ForPointeeType=*/true) 776 .getAsMaybeAlign(); 777 778 // The glvalue must be suitably aligned. 779 if (AlignVal && *AlignVal > llvm::Align(1) && 780 (!PtrToAlloca || PtrToAlloca->getAlign() < *AlignVal)) { 781 PtrAsInt = Builder.CreatePtrToInt(Ptr, IntPtrTy); 782 llvm::Value *Align = Builder.CreateAnd( 783 PtrAsInt, llvm::ConstantInt::get(IntPtrTy, AlignVal->value() - 1)); 784 llvm::Value *Aligned = 785 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0)); 786 if (Aligned != True) 787 Checks.push_back(std::make_pair(Aligned, SanitizerKind::Alignment)); 788 } 789 } 790 791 if (Checks.size() > 0) { 792 llvm::Constant *StaticData[] = { 793 EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(Ty), 794 llvm::ConstantInt::get(Int8Ty, AlignVal ? llvm::Log2(*AlignVal) : 1), 795 llvm::ConstantInt::get(Int8Ty, TCK)}; 796 EmitCheck(Checks, SanitizerHandler::TypeMismatch, StaticData, 797 PtrAsInt ? PtrAsInt : Ptr); 798 } 799 800 // If possible, check that the vptr indicates that there is a subobject of 801 // type Ty at offset zero within this object. 802 // 803 // C++11 [basic.life]p5,6: 804 // [For storage which does not refer to an object within its lifetime] 805 // The program has undefined behavior if: 806 // -- the [pointer or glvalue] is used to access a non-static data member 807 // or call a non-static member function 808 if (SanOpts.has(SanitizerKind::Vptr) && 809 !SkippedChecks.has(SanitizerKind::Vptr) && isVptrCheckRequired(TCK, Ty)) { 810 // Ensure that the pointer is non-null before loading it. If there is no 811 // compile-time guarantee, reuse the run-time null check or emit a new one. 812 if (!IsGuaranteedNonNull) { 813 if (!IsNonNull) 814 IsNonNull = Builder.CreateIsNotNull(Ptr); 815 if (!Done) 816 Done = createBasicBlock("vptr.null"); 817 llvm::BasicBlock *VptrNotNull = createBasicBlock("vptr.not.null"); 818 Builder.CreateCondBr(IsNonNull, VptrNotNull, Done); 819 EmitBlock(VptrNotNull); 820 } 821 822 // Compute a deterministic hash of the mangled name of the type. 823 SmallString<64> MangledName; 824 llvm::raw_svector_ostream Out(MangledName); 825 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(), 826 Out); 827 828 // Contained in NoSanitizeList based on the mangled type. 829 if (!CGM.getContext().getNoSanitizeList().containsType(SanitizerKind::Vptr, 830 Out.str())) { 831 // Load the vptr, and mix it with TypeHash. 832 llvm::Value *TypeHash = 833 llvm::ConstantInt::get(Int64Ty, xxh3_64bits(Out.str())); 834 835 llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0); 836 Address VPtrAddr(Ptr, IntPtrTy, getPointerAlign()); 837 llvm::Value *VPtrVal = GetVTablePtr(VPtrAddr, VPtrTy, 838 Ty->getAsCXXRecordDecl(), 839 VTableAuthMode::UnsafeUbsanStrip); 840 VPtrVal = Builder.CreateBitOrPointerCast(VPtrVal, IntPtrTy); 841 842 llvm::Value *Hash = 843 emitHashMix(Builder, TypeHash, Builder.CreateZExt(VPtrVal, Int64Ty)); 844 Hash = Builder.CreateTrunc(Hash, IntPtrTy); 845 846 // Look the hash up in our cache. 847 const int CacheSize = 128; 848 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize); 849 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable, 850 "__ubsan_vptr_type_cache"); 851 llvm::Value *Slot = Builder.CreateAnd(Hash, 852 llvm::ConstantInt::get(IntPtrTy, 853 CacheSize-1)); 854 llvm::Value *Indices[] = { Builder.getInt32(0), Slot }; 855 llvm::Value *CacheVal = Builder.CreateAlignedLoad( 856 IntPtrTy, Builder.CreateInBoundsGEP(HashTable, Cache, Indices), 857 getPointerAlign()); 858 859 // If the hash isn't in the cache, call a runtime handler to perform the 860 // hard work of checking whether the vptr is for an object of the right 861 // type. This will either fill in the cache and return, or produce a 862 // diagnostic. 863 llvm::Value *EqualHash = Builder.CreateICmpEQ(CacheVal, Hash); 864 llvm::Constant *StaticData[] = { 865 EmitCheckSourceLocation(Loc), 866 EmitCheckTypeDescriptor(Ty), 867 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()), 868 llvm::ConstantInt::get(Int8Ty, TCK) 869 }; 870 llvm::Value *DynamicData[] = { Ptr, Hash }; 871 EmitCheck(std::make_pair(EqualHash, SanitizerKind::Vptr), 872 SanitizerHandler::DynamicTypeCacheMiss, StaticData, 873 DynamicData); 874 } 875 } 876 877 if (Done) { 878 Builder.CreateBr(Done); 879 EmitBlock(Done); 880 } 881 } 882 883 llvm::Value *CodeGenFunction::LoadPassedObjectSize(const Expr *E, 884 QualType EltTy) { 885 ASTContext &C = getContext(); 886 uint64_t EltSize = C.getTypeSizeInChars(EltTy).getQuantity(); 887 if (!EltSize) 888 return nullptr; 889 890 auto *ArrayDeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts()); 891 if (!ArrayDeclRef) 892 return nullptr; 893 894 auto *ParamDecl = dyn_cast<ParmVarDecl>(ArrayDeclRef->getDecl()); 895 if (!ParamDecl) 896 return nullptr; 897 898 auto *POSAttr = ParamDecl->getAttr<PassObjectSizeAttr>(); 899 if (!POSAttr) 900 return nullptr; 901 902 // Don't load the size if it's a lower bound. 903 int POSType = POSAttr->getType(); 904 if (POSType != 0 && POSType != 1) 905 return nullptr; 906 907 // Find the implicit size parameter. 908 auto PassedSizeIt = SizeArguments.find(ParamDecl); 909 if (PassedSizeIt == SizeArguments.end()) 910 return nullptr; 911 912 const ImplicitParamDecl *PassedSizeDecl = PassedSizeIt->second; 913 assert(LocalDeclMap.count(PassedSizeDecl) && "Passed size not loadable"); 914 Address AddrOfSize = LocalDeclMap.find(PassedSizeDecl)->second; 915 llvm::Value *SizeInBytes = EmitLoadOfScalar(AddrOfSize, /*Volatile=*/false, 916 C.getSizeType(), E->getExprLoc()); 917 llvm::Value *SizeOfElement = 918 llvm::ConstantInt::get(SizeInBytes->getType(), EltSize); 919 return Builder.CreateUDiv(SizeInBytes, SizeOfElement); 920 } 921 922 /// If Base is known to point to the start of an array, return the length of 923 /// that array. Return 0 if the length cannot be determined. 924 static llvm::Value *getArrayIndexingBound(CodeGenFunction &CGF, 925 const Expr *Base, 926 QualType &IndexedType, 927 LangOptions::StrictFlexArraysLevelKind 928 StrictFlexArraysLevel) { 929 // For the vector indexing extension, the bound is the number of elements. 930 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) { 931 IndexedType = Base->getType(); 932 return CGF.Builder.getInt32(VT->getNumElements()); 933 } 934 935 Base = Base->IgnoreParens(); 936 937 if (const auto *CE = dyn_cast<CastExpr>(Base)) { 938 if (CE->getCastKind() == CK_ArrayToPointerDecay && 939 !CE->getSubExpr()->isFlexibleArrayMemberLike(CGF.getContext(), 940 StrictFlexArraysLevel)) { 941 CodeGenFunction::SanitizerScope SanScope(&CGF); 942 943 IndexedType = CE->getSubExpr()->getType(); 944 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe(); 945 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT)) 946 return CGF.Builder.getInt(CAT->getSize()); 947 948 if (const auto *VAT = dyn_cast<VariableArrayType>(AT)) 949 return CGF.getVLASize(VAT).NumElts; 950 // Ignore pass_object_size here. It's not applicable on decayed pointers. 951 } 952 } 953 954 CodeGenFunction::SanitizerScope SanScope(&CGF); 955 956 QualType EltTy{Base->getType()->getPointeeOrArrayElementType(), 0}; 957 if (llvm::Value *POS = CGF.LoadPassedObjectSize(Base, EltTy)) { 958 IndexedType = Base->getType(); 959 return POS; 960 } 961 962 return nullptr; 963 } 964 965 namespace { 966 967 /// \p StructAccessBase returns the base \p Expr of a field access. It returns 968 /// either a \p DeclRefExpr, representing the base pointer to the struct, i.e.: 969 /// 970 /// p in p-> a.b.c 971 /// 972 /// or a \p MemberExpr, if the \p MemberExpr has the \p RecordDecl we're 973 /// looking for: 974 /// 975 /// struct s { 976 /// struct s *ptr; 977 /// int count; 978 /// char array[] __attribute__((counted_by(count))); 979 /// }; 980 /// 981 /// If we have an expression like \p p->ptr->array[index], we want the 982 /// \p MemberExpr for \p p->ptr instead of \p p. 983 class StructAccessBase 984 : public ConstStmtVisitor<StructAccessBase, const Expr *> { 985 const RecordDecl *ExpectedRD; 986 987 bool IsExpectedRecordDecl(const Expr *E) const { 988 QualType Ty = E->getType(); 989 if (Ty->isPointerType()) 990 Ty = Ty->getPointeeType(); 991 return ExpectedRD == Ty->getAsRecordDecl(); 992 } 993 994 public: 995 StructAccessBase(const RecordDecl *ExpectedRD) : ExpectedRD(ExpectedRD) {} 996 997 //===--------------------------------------------------------------------===// 998 // Visitor Methods 999 //===--------------------------------------------------------------------===// 1000 1001 // NOTE: If we build C++ support for counted_by, then we'll have to handle 1002 // horrors like this: 1003 // 1004 // struct S { 1005 // int x, y; 1006 // int blah[] __attribute__((counted_by(x))); 1007 // } s; 1008 // 1009 // int foo(int index, int val) { 1010 // int (S::*IHatePMDs)[] = &S::blah; 1011 // (s.*IHatePMDs)[index] = val; 1012 // } 1013 1014 const Expr *Visit(const Expr *E) { 1015 return ConstStmtVisitor<StructAccessBase, const Expr *>::Visit(E); 1016 } 1017 1018 const Expr *VisitStmt(const Stmt *S) { return nullptr; } 1019 1020 // These are the types we expect to return (in order of most to least 1021 // likely): 1022 // 1023 // 1. DeclRefExpr - This is the expression for the base of the structure. 1024 // It's exactly what we want to build an access to the \p counted_by 1025 // field. 1026 // 2. MemberExpr - This is the expression that has the same \p RecordDecl 1027 // as the flexble array member's lexical enclosing \p RecordDecl. This 1028 // allows us to catch things like: "p->p->array" 1029 // 3. CompoundLiteralExpr - This is for people who create something 1030 // heretical like (struct foo has a flexible array member): 1031 // 1032 // (struct foo){ 1, 2 }.blah[idx]; 1033 const Expr *VisitDeclRefExpr(const DeclRefExpr *E) { 1034 return IsExpectedRecordDecl(E) ? E : nullptr; 1035 } 1036 const Expr *VisitMemberExpr(const MemberExpr *E) { 1037 if (IsExpectedRecordDecl(E) && E->isArrow()) 1038 return E; 1039 const Expr *Res = Visit(E->getBase()); 1040 return !Res && IsExpectedRecordDecl(E) ? E : Res; 1041 } 1042 const Expr *VisitCompoundLiteralExpr(const CompoundLiteralExpr *E) { 1043 return IsExpectedRecordDecl(E) ? E : nullptr; 1044 } 1045 const Expr *VisitCallExpr(const CallExpr *E) { 1046 return IsExpectedRecordDecl(E) ? E : nullptr; 1047 } 1048 1049 const Expr *VisitArraySubscriptExpr(const ArraySubscriptExpr *E) { 1050 if (IsExpectedRecordDecl(E)) 1051 return E; 1052 return Visit(E->getBase()); 1053 } 1054 const Expr *VisitCastExpr(const CastExpr *E) { 1055 if (E->getCastKind() == CK_LValueToRValue) 1056 return IsExpectedRecordDecl(E) ? E : nullptr; 1057 return Visit(E->getSubExpr()); 1058 } 1059 const Expr *VisitParenExpr(const ParenExpr *E) { 1060 return Visit(E->getSubExpr()); 1061 } 1062 const Expr *VisitUnaryAddrOf(const UnaryOperator *E) { 1063 return Visit(E->getSubExpr()); 1064 } 1065 const Expr *VisitUnaryDeref(const UnaryOperator *E) { 1066 return Visit(E->getSubExpr()); 1067 } 1068 }; 1069 1070 } // end anonymous namespace 1071 1072 using RecIndicesTy = 1073 SmallVector<std::pair<const RecordDecl *, llvm::Value *>, 8>; 1074 1075 static bool getGEPIndicesToField(CodeGenFunction &CGF, const RecordDecl *RD, 1076 const FieldDecl *Field, 1077 RecIndicesTy &Indices) { 1078 const CGRecordLayout &Layout = CGF.CGM.getTypes().getCGRecordLayout(RD); 1079 int64_t FieldNo = -1; 1080 for (const FieldDecl *FD : RD->fields()) { 1081 if (!Layout.containsFieldDecl(FD)) 1082 // This could happen if the field has a struct type that's empty. I don't 1083 // know why either. 1084 continue; 1085 1086 FieldNo = Layout.getLLVMFieldNo(FD); 1087 if (FD == Field) { 1088 Indices.emplace_back(std::make_pair(RD, CGF.Builder.getInt32(FieldNo))); 1089 return true; 1090 } 1091 1092 QualType Ty = FD->getType(); 1093 if (Ty->isRecordType()) { 1094 if (getGEPIndicesToField(CGF, Ty->getAsRecordDecl(), Field, Indices)) { 1095 if (RD->isUnion()) 1096 FieldNo = 0; 1097 Indices.emplace_back(std::make_pair(RD, CGF.Builder.getInt32(FieldNo))); 1098 return true; 1099 } 1100 } 1101 } 1102 1103 return false; 1104 } 1105 1106 /// This method is typically called in contexts where we can't generate 1107 /// side-effects, like in __builtin_dynamic_object_size. When finding 1108 /// expressions, only choose those that have either already been emitted or can 1109 /// be loaded without side-effects. 1110 /// 1111 /// - \p FAMDecl: the \p Decl for the flexible array member. It may not be 1112 /// within the top-level struct. 1113 /// - \p CountDecl: must be within the same non-anonymous struct as \p FAMDecl. 1114 llvm::Value *CodeGenFunction::EmitCountedByFieldExpr( 1115 const Expr *Base, const FieldDecl *FAMDecl, const FieldDecl *CountDecl) { 1116 const RecordDecl *RD = CountDecl->getParent()->getOuterLexicalRecordContext(); 1117 1118 // Find the base struct expr (i.e. p in p->a.b.c.d). 1119 const Expr *StructBase = StructAccessBase(RD).Visit(Base); 1120 if (!StructBase || StructBase->HasSideEffects(getContext())) 1121 return nullptr; 1122 1123 llvm::Value *Res = nullptr; 1124 if (StructBase->getType()->isPointerType()) { 1125 LValueBaseInfo BaseInfo; 1126 TBAAAccessInfo TBAAInfo; 1127 Address Addr = EmitPointerWithAlignment(StructBase, &BaseInfo, &TBAAInfo); 1128 Res = Addr.emitRawPointer(*this); 1129 } else if (StructBase->isLValue()) { 1130 LValue LV = EmitLValue(StructBase); 1131 Address Addr = LV.getAddress(); 1132 Res = Addr.emitRawPointer(*this); 1133 } else { 1134 return nullptr; 1135 } 1136 1137 llvm::Value *Zero = Builder.getInt32(0); 1138 RecIndicesTy Indices; 1139 1140 getGEPIndicesToField(*this, RD, CountDecl, Indices); 1141 1142 for (auto I = Indices.rbegin(), E = Indices.rend(); I != E; ++I) 1143 Res = Builder.CreateInBoundsGEP( 1144 ConvertType(QualType(I->first->getTypeForDecl(), 0)), Res, 1145 {Zero, I->second}, "..counted_by.gep"); 1146 1147 return Builder.CreateAlignedLoad(ConvertType(CountDecl->getType()), Res, 1148 getIntAlign(), "..counted_by.load"); 1149 } 1150 1151 const FieldDecl *CodeGenFunction::FindCountedByField(const FieldDecl *FD) { 1152 if (!FD) 1153 return nullptr; 1154 1155 const auto *CAT = FD->getType()->getAs<CountAttributedType>(); 1156 if (!CAT) 1157 return nullptr; 1158 1159 const auto *CountDRE = cast<DeclRefExpr>(CAT->getCountExpr()); 1160 const auto *CountDecl = CountDRE->getDecl(); 1161 if (const auto *IFD = dyn_cast<IndirectFieldDecl>(CountDecl)) 1162 CountDecl = IFD->getAnonField(); 1163 1164 return dyn_cast<FieldDecl>(CountDecl); 1165 } 1166 1167 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base, 1168 llvm::Value *Index, QualType IndexType, 1169 bool Accessed) { 1170 assert(SanOpts.has(SanitizerKind::ArrayBounds) && 1171 "should not be called unless adding bounds checks"); 1172 const LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel = 1173 getLangOpts().getStrictFlexArraysLevel(); 1174 QualType IndexedType; 1175 llvm::Value *Bound = 1176 getArrayIndexingBound(*this, Base, IndexedType, StrictFlexArraysLevel); 1177 1178 EmitBoundsCheckImpl(E, Bound, Index, IndexType, IndexedType, Accessed); 1179 } 1180 1181 void CodeGenFunction::EmitBoundsCheckImpl(const Expr *E, llvm::Value *Bound, 1182 llvm::Value *Index, 1183 QualType IndexType, 1184 QualType IndexedType, bool Accessed) { 1185 if (!Bound) 1186 return; 1187 1188 SanitizerScope SanScope(this); 1189 1190 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType(); 1191 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned); 1192 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false); 1193 1194 llvm::Constant *StaticData[] = { 1195 EmitCheckSourceLocation(E->getExprLoc()), 1196 EmitCheckTypeDescriptor(IndexedType), 1197 EmitCheckTypeDescriptor(IndexType) 1198 }; 1199 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal) 1200 : Builder.CreateICmpULE(IndexVal, BoundVal); 1201 EmitCheck(std::make_pair(Check, SanitizerKind::ArrayBounds), 1202 SanitizerHandler::OutOfBounds, StaticData, Index); 1203 } 1204 1205 CodeGenFunction::ComplexPairTy CodeGenFunction:: 1206 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV, 1207 bool isInc, bool isPre) { 1208 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc()); 1209 1210 llvm::Value *NextVal; 1211 if (isa<llvm::IntegerType>(InVal.first->getType())) { 1212 uint64_t AmountVal = isInc ? 1 : -1; 1213 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true); 1214 1215 // Add the inc/dec to the real part. 1216 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec"); 1217 } else { 1218 QualType ElemTy = E->getType()->castAs<ComplexType>()->getElementType(); 1219 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1); 1220 if (!isInc) 1221 FVal.changeSign(); 1222 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal); 1223 1224 // Add the inc/dec to the real part. 1225 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec"); 1226 } 1227 1228 ComplexPairTy IncVal(NextVal, InVal.second); 1229 1230 // Store the updated result through the lvalue. 1231 EmitStoreOfComplex(IncVal, LV, /*init*/ false); 1232 if (getLangOpts().OpenMP) 1233 CGM.getOpenMPRuntime().checkAndEmitLastprivateConditional(*this, 1234 E->getSubExpr()); 1235 1236 // If this is a postinc, return the value read from memory, otherwise use the 1237 // updated value. 1238 return isPre ? IncVal : InVal; 1239 } 1240 1241 void CodeGenModule::EmitExplicitCastExprType(const ExplicitCastExpr *E, 1242 CodeGenFunction *CGF) { 1243 // Bind VLAs in the cast type. 1244 if (CGF && E->getType()->isVariablyModifiedType()) 1245 CGF->EmitVariablyModifiedType(E->getType()); 1246 1247 if (CGDebugInfo *DI = getModuleDebugInfo()) 1248 DI->EmitExplicitCastType(E->getType()); 1249 } 1250 1251 //===----------------------------------------------------------------------===// 1252 // LValue Expression Emission 1253 //===----------------------------------------------------------------------===// 1254 1255 static Address EmitPointerWithAlignment(const Expr *E, LValueBaseInfo *BaseInfo, 1256 TBAAAccessInfo *TBAAInfo, 1257 KnownNonNull_t IsKnownNonNull, 1258 CodeGenFunction &CGF) { 1259 // We allow this with ObjC object pointers because of fragile ABIs. 1260 assert(E->getType()->isPointerType() || 1261 E->getType()->isObjCObjectPointerType()); 1262 E = E->IgnoreParens(); 1263 1264 // Casts: 1265 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) { 1266 if (const auto *ECE = dyn_cast<ExplicitCastExpr>(CE)) 1267 CGF.CGM.EmitExplicitCastExprType(ECE, &CGF); 1268 1269 switch (CE->getCastKind()) { 1270 // Non-converting casts (but not C's implicit conversion from void*). 1271 case CK_BitCast: 1272 case CK_NoOp: 1273 case CK_AddressSpaceConversion: 1274 if (auto PtrTy = CE->getSubExpr()->getType()->getAs<PointerType>()) { 1275 if (PtrTy->getPointeeType()->isVoidType()) 1276 break; 1277 1278 LValueBaseInfo InnerBaseInfo; 1279 TBAAAccessInfo InnerTBAAInfo; 1280 Address Addr = CGF.EmitPointerWithAlignment( 1281 CE->getSubExpr(), &InnerBaseInfo, &InnerTBAAInfo, IsKnownNonNull); 1282 if (BaseInfo) *BaseInfo = InnerBaseInfo; 1283 if (TBAAInfo) *TBAAInfo = InnerTBAAInfo; 1284 1285 if (isa<ExplicitCastExpr>(CE)) { 1286 LValueBaseInfo TargetTypeBaseInfo; 1287 TBAAAccessInfo TargetTypeTBAAInfo; 1288 CharUnits Align = CGF.CGM.getNaturalPointeeTypeAlignment( 1289 E->getType(), &TargetTypeBaseInfo, &TargetTypeTBAAInfo); 1290 if (TBAAInfo) 1291 *TBAAInfo = 1292 CGF.CGM.mergeTBAAInfoForCast(*TBAAInfo, TargetTypeTBAAInfo); 1293 // If the source l-value is opaque, honor the alignment of the 1294 // casted-to type. 1295 if (InnerBaseInfo.getAlignmentSource() != AlignmentSource::Decl) { 1296 if (BaseInfo) 1297 BaseInfo->mergeForCast(TargetTypeBaseInfo); 1298 Addr.setAlignment(Align); 1299 } 1300 } 1301 1302 if (CGF.SanOpts.has(SanitizerKind::CFIUnrelatedCast) && 1303 CE->getCastKind() == CK_BitCast) { 1304 if (auto PT = E->getType()->getAs<PointerType>()) 1305 CGF.EmitVTablePtrCheckForCast(PT->getPointeeType(), Addr, 1306 /*MayBeNull=*/true, 1307 CodeGenFunction::CFITCK_UnrelatedCast, 1308 CE->getBeginLoc()); 1309 } 1310 1311 llvm::Type *ElemTy = 1312 CGF.ConvertTypeForMem(E->getType()->getPointeeType()); 1313 Addr = Addr.withElementType(ElemTy); 1314 if (CE->getCastKind() == CK_AddressSpaceConversion) 1315 Addr = CGF.Builder.CreateAddrSpaceCast( 1316 Addr, CGF.ConvertType(E->getType()), ElemTy); 1317 return CGF.authPointerToPointerCast(Addr, CE->getSubExpr()->getType(), 1318 CE->getType()); 1319 } 1320 break; 1321 1322 // Array-to-pointer decay. 1323 case CK_ArrayToPointerDecay: 1324 return CGF.EmitArrayToPointerDecay(CE->getSubExpr(), BaseInfo, TBAAInfo); 1325 1326 // Derived-to-base conversions. 1327 case CK_UncheckedDerivedToBase: 1328 case CK_DerivedToBase: { 1329 // TODO: Support accesses to members of base classes in TBAA. For now, we 1330 // conservatively pretend that the complete object is of the base class 1331 // type. 1332 if (TBAAInfo) 1333 *TBAAInfo = CGF.CGM.getTBAAAccessInfo(E->getType()); 1334 Address Addr = CGF.EmitPointerWithAlignment( 1335 CE->getSubExpr(), BaseInfo, nullptr, 1336 (KnownNonNull_t)(IsKnownNonNull || 1337 CE->getCastKind() == CK_UncheckedDerivedToBase)); 1338 auto Derived = CE->getSubExpr()->getType()->getPointeeCXXRecordDecl(); 1339 return CGF.GetAddressOfBaseClass( 1340 Addr, Derived, CE->path_begin(), CE->path_end(), 1341 CGF.ShouldNullCheckClassCastValue(CE), CE->getExprLoc()); 1342 } 1343 1344 // TODO: Is there any reason to treat base-to-derived conversions 1345 // specially? 1346 default: 1347 break; 1348 } 1349 } 1350 1351 // Unary &. 1352 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) { 1353 if (UO->getOpcode() == UO_AddrOf) { 1354 LValue LV = CGF.EmitLValue(UO->getSubExpr(), IsKnownNonNull); 1355 if (BaseInfo) *BaseInfo = LV.getBaseInfo(); 1356 if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo(); 1357 return LV.getAddress(); 1358 } 1359 } 1360 1361 // std::addressof and variants. 1362 if (auto *Call = dyn_cast<CallExpr>(E)) { 1363 switch (Call->getBuiltinCallee()) { 1364 default: 1365 break; 1366 case Builtin::BIaddressof: 1367 case Builtin::BI__addressof: 1368 case Builtin::BI__builtin_addressof: { 1369 LValue LV = CGF.EmitLValue(Call->getArg(0), IsKnownNonNull); 1370 if (BaseInfo) *BaseInfo = LV.getBaseInfo(); 1371 if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo(); 1372 return LV.getAddress(); 1373 } 1374 } 1375 } 1376 1377 // TODO: conditional operators, comma. 1378 1379 // Otherwise, use the alignment of the type. 1380 return CGF.makeNaturalAddressForPointer( 1381 CGF.EmitScalarExpr(E), E->getType()->getPointeeType(), CharUnits(), 1382 /*ForPointeeType=*/true, BaseInfo, TBAAInfo, IsKnownNonNull); 1383 } 1384 1385 /// EmitPointerWithAlignment - Given an expression of pointer type, try to 1386 /// derive a more accurate bound on the alignment of the pointer. 1387 Address CodeGenFunction::EmitPointerWithAlignment( 1388 const Expr *E, LValueBaseInfo *BaseInfo, TBAAAccessInfo *TBAAInfo, 1389 KnownNonNull_t IsKnownNonNull) { 1390 Address Addr = 1391 ::EmitPointerWithAlignment(E, BaseInfo, TBAAInfo, IsKnownNonNull, *this); 1392 if (IsKnownNonNull && !Addr.isKnownNonNull()) 1393 Addr.setKnownNonNull(); 1394 return Addr; 1395 } 1396 1397 llvm::Value *CodeGenFunction::EmitNonNullRValueCheck(RValue RV, QualType T) { 1398 llvm::Value *V = RV.getScalarVal(); 1399 if (auto MPT = T->getAs<MemberPointerType>()) 1400 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, V, MPT); 1401 return Builder.CreateICmpNE(V, llvm::Constant::getNullValue(V->getType())); 1402 } 1403 1404 RValue CodeGenFunction::GetUndefRValue(QualType Ty) { 1405 if (Ty->isVoidType()) 1406 return RValue::get(nullptr); 1407 1408 switch (getEvaluationKind(Ty)) { 1409 case TEK_Complex: { 1410 llvm::Type *EltTy = 1411 ConvertType(Ty->castAs<ComplexType>()->getElementType()); 1412 llvm::Value *U = llvm::UndefValue::get(EltTy); 1413 return RValue::getComplex(std::make_pair(U, U)); 1414 } 1415 1416 // If this is a use of an undefined aggregate type, the aggregate must have an 1417 // identifiable address. Just because the contents of the value are undefined 1418 // doesn't mean that the address can't be taken and compared. 1419 case TEK_Aggregate: { 1420 Address DestPtr = CreateMemTemp(Ty, "undef.agg.tmp"); 1421 return RValue::getAggregate(DestPtr); 1422 } 1423 1424 case TEK_Scalar: 1425 return RValue::get(llvm::UndefValue::get(ConvertType(Ty))); 1426 } 1427 llvm_unreachable("bad evaluation kind"); 1428 } 1429 1430 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E, 1431 const char *Name) { 1432 ErrorUnsupported(E, Name); 1433 return GetUndefRValue(E->getType()); 1434 } 1435 1436 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E, 1437 const char *Name) { 1438 ErrorUnsupported(E, Name); 1439 llvm::Type *ElTy = ConvertType(E->getType()); 1440 llvm::Type *Ty = UnqualPtrTy; 1441 return MakeAddrLValue( 1442 Address(llvm::UndefValue::get(Ty), ElTy, CharUnits::One()), E->getType()); 1443 } 1444 1445 bool CodeGenFunction::IsWrappedCXXThis(const Expr *Obj) { 1446 const Expr *Base = Obj; 1447 while (!isa<CXXThisExpr>(Base)) { 1448 // The result of a dynamic_cast can be null. 1449 if (isa<CXXDynamicCastExpr>(Base)) 1450 return false; 1451 1452 if (const auto *CE = dyn_cast<CastExpr>(Base)) { 1453 Base = CE->getSubExpr(); 1454 } else if (const auto *PE = dyn_cast<ParenExpr>(Base)) { 1455 Base = PE->getSubExpr(); 1456 } else if (const auto *UO = dyn_cast<UnaryOperator>(Base)) { 1457 if (UO->getOpcode() == UO_Extension) 1458 Base = UO->getSubExpr(); 1459 else 1460 return false; 1461 } else { 1462 return false; 1463 } 1464 } 1465 return true; 1466 } 1467 1468 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) { 1469 LValue LV; 1470 if (SanOpts.has(SanitizerKind::ArrayBounds) && isa<ArraySubscriptExpr>(E)) 1471 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true); 1472 else 1473 LV = EmitLValue(E); 1474 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) { 1475 SanitizerSet SkippedChecks; 1476 if (const auto *ME = dyn_cast<MemberExpr>(E)) { 1477 bool IsBaseCXXThis = IsWrappedCXXThis(ME->getBase()); 1478 if (IsBaseCXXThis) 1479 SkippedChecks.set(SanitizerKind::Alignment, true); 1480 if (IsBaseCXXThis || isa<DeclRefExpr>(ME->getBase())) 1481 SkippedChecks.set(SanitizerKind::Null, true); 1482 } 1483 EmitTypeCheck(TCK, E->getExprLoc(), LV, E->getType(), SkippedChecks); 1484 } 1485 return LV; 1486 } 1487 1488 /// EmitLValue - Emit code to compute a designator that specifies the location 1489 /// of the expression. 1490 /// 1491 /// This can return one of two things: a simple address or a bitfield reference. 1492 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be 1493 /// an LLVM pointer type. 1494 /// 1495 /// If this returns a bitfield reference, nothing about the pointee type of the 1496 /// LLVM value is known: For example, it may not be a pointer to an integer. 1497 /// 1498 /// If this returns a normal address, and if the lvalue's C type is fixed size, 1499 /// this method guarantees that the returned pointer type will point to an LLVM 1500 /// type of the same size of the lvalue's type. If the lvalue has a variable 1501 /// length type, this is not possible. 1502 /// 1503 LValue CodeGenFunction::EmitLValue(const Expr *E, 1504 KnownNonNull_t IsKnownNonNull) { 1505 LValue LV = EmitLValueHelper(E, IsKnownNonNull); 1506 if (IsKnownNonNull && !LV.isKnownNonNull()) 1507 LV.setKnownNonNull(); 1508 return LV; 1509 } 1510 1511 static QualType getConstantExprReferredType(const FullExpr *E, 1512 const ASTContext &Ctx) { 1513 const Expr *SE = E->getSubExpr()->IgnoreImplicit(); 1514 if (isa<OpaqueValueExpr>(SE)) 1515 return SE->getType(); 1516 return cast<CallExpr>(SE)->getCallReturnType(Ctx)->getPointeeType(); 1517 } 1518 1519 LValue CodeGenFunction::EmitLValueHelper(const Expr *E, 1520 KnownNonNull_t IsKnownNonNull) { 1521 ApplyDebugLocation DL(*this, E); 1522 switch (E->getStmtClass()) { 1523 default: return EmitUnsupportedLValue(E, "l-value expression"); 1524 1525 case Expr::ObjCPropertyRefExprClass: 1526 llvm_unreachable("cannot emit a property reference directly"); 1527 1528 case Expr::ObjCSelectorExprClass: 1529 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E)); 1530 case Expr::ObjCIsaExprClass: 1531 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E)); 1532 case Expr::BinaryOperatorClass: 1533 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E)); 1534 case Expr::CompoundAssignOperatorClass: { 1535 QualType Ty = E->getType(); 1536 if (const AtomicType *AT = Ty->getAs<AtomicType>()) 1537 Ty = AT->getValueType(); 1538 if (!Ty->isAnyComplexType()) 1539 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E)); 1540 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E)); 1541 } 1542 case Expr::CallExprClass: 1543 case Expr::CXXMemberCallExprClass: 1544 case Expr::CXXOperatorCallExprClass: 1545 case Expr::UserDefinedLiteralClass: 1546 return EmitCallExprLValue(cast<CallExpr>(E)); 1547 case Expr::CXXRewrittenBinaryOperatorClass: 1548 return EmitLValue(cast<CXXRewrittenBinaryOperator>(E)->getSemanticForm(), 1549 IsKnownNonNull); 1550 case Expr::VAArgExprClass: 1551 return EmitVAArgExprLValue(cast<VAArgExpr>(E)); 1552 case Expr::DeclRefExprClass: 1553 return EmitDeclRefLValue(cast<DeclRefExpr>(E)); 1554 case Expr::ConstantExprClass: { 1555 const ConstantExpr *CE = cast<ConstantExpr>(E); 1556 if (llvm::Value *Result = ConstantEmitter(*this).tryEmitConstantExpr(CE)) { 1557 QualType RetType = getConstantExprReferredType(CE, getContext()); 1558 return MakeNaturalAlignAddrLValue(Result, RetType); 1559 } 1560 return EmitLValue(cast<ConstantExpr>(E)->getSubExpr(), IsKnownNonNull); 1561 } 1562 case Expr::ParenExprClass: 1563 return EmitLValue(cast<ParenExpr>(E)->getSubExpr(), IsKnownNonNull); 1564 case Expr::GenericSelectionExprClass: 1565 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr(), 1566 IsKnownNonNull); 1567 case Expr::PredefinedExprClass: 1568 return EmitPredefinedLValue(cast<PredefinedExpr>(E)); 1569 case Expr::StringLiteralClass: 1570 return EmitStringLiteralLValue(cast<StringLiteral>(E)); 1571 case Expr::ObjCEncodeExprClass: 1572 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E)); 1573 case Expr::PseudoObjectExprClass: 1574 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E)); 1575 case Expr::InitListExprClass: 1576 return EmitInitListLValue(cast<InitListExpr>(E)); 1577 case Expr::CXXTemporaryObjectExprClass: 1578 case Expr::CXXConstructExprClass: 1579 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E)); 1580 case Expr::CXXBindTemporaryExprClass: 1581 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E)); 1582 case Expr::CXXUuidofExprClass: 1583 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E)); 1584 case Expr::LambdaExprClass: 1585 return EmitAggExprToLValue(E); 1586 1587 case Expr::ExprWithCleanupsClass: { 1588 const auto *cleanups = cast<ExprWithCleanups>(E); 1589 RunCleanupsScope Scope(*this); 1590 LValue LV = EmitLValue(cleanups->getSubExpr(), IsKnownNonNull); 1591 if (LV.isSimple()) { 1592 // Defend against branches out of gnu statement expressions surrounded by 1593 // cleanups. 1594 Address Addr = LV.getAddress(); 1595 llvm::Value *V = Addr.getBasePointer(); 1596 Scope.ForceCleanup({&V}); 1597 Addr.replaceBasePointer(V); 1598 return LValue::MakeAddr(Addr, LV.getType(), getContext(), 1599 LV.getBaseInfo(), LV.getTBAAInfo()); 1600 } 1601 // FIXME: Is it possible to create an ExprWithCleanups that produces a 1602 // bitfield lvalue or some other non-simple lvalue? 1603 return LV; 1604 } 1605 1606 case Expr::CXXDefaultArgExprClass: { 1607 auto *DAE = cast<CXXDefaultArgExpr>(E); 1608 CXXDefaultArgExprScope Scope(*this, DAE); 1609 return EmitLValue(DAE->getExpr(), IsKnownNonNull); 1610 } 1611 case Expr::CXXDefaultInitExprClass: { 1612 auto *DIE = cast<CXXDefaultInitExpr>(E); 1613 CXXDefaultInitExprScope Scope(*this, DIE); 1614 return EmitLValue(DIE->getExpr(), IsKnownNonNull); 1615 } 1616 case Expr::CXXTypeidExprClass: 1617 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E)); 1618 1619 case Expr::ObjCMessageExprClass: 1620 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E)); 1621 case Expr::ObjCIvarRefExprClass: 1622 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E)); 1623 case Expr::StmtExprClass: 1624 return EmitStmtExprLValue(cast<StmtExpr>(E)); 1625 case Expr::UnaryOperatorClass: 1626 return EmitUnaryOpLValue(cast<UnaryOperator>(E)); 1627 case Expr::ArraySubscriptExprClass: 1628 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E)); 1629 case Expr::MatrixSubscriptExprClass: 1630 return EmitMatrixSubscriptExpr(cast<MatrixSubscriptExpr>(E)); 1631 case Expr::ArraySectionExprClass: 1632 return EmitArraySectionExpr(cast<ArraySectionExpr>(E)); 1633 case Expr::ExtVectorElementExprClass: 1634 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E)); 1635 case Expr::CXXThisExprClass: 1636 return MakeAddrLValue(LoadCXXThisAddress(), E->getType()); 1637 case Expr::MemberExprClass: 1638 return EmitMemberExpr(cast<MemberExpr>(E)); 1639 case Expr::CompoundLiteralExprClass: 1640 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E)); 1641 case Expr::ConditionalOperatorClass: 1642 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E)); 1643 case Expr::BinaryConditionalOperatorClass: 1644 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E)); 1645 case Expr::ChooseExprClass: 1646 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr(), IsKnownNonNull); 1647 case Expr::OpaqueValueExprClass: 1648 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E)); 1649 case Expr::SubstNonTypeTemplateParmExprClass: 1650 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement(), 1651 IsKnownNonNull); 1652 case Expr::ImplicitCastExprClass: 1653 case Expr::CStyleCastExprClass: 1654 case Expr::CXXFunctionalCastExprClass: 1655 case Expr::CXXStaticCastExprClass: 1656 case Expr::CXXDynamicCastExprClass: 1657 case Expr::CXXReinterpretCastExprClass: 1658 case Expr::CXXConstCastExprClass: 1659 case Expr::CXXAddrspaceCastExprClass: 1660 case Expr::ObjCBridgedCastExprClass: 1661 return EmitCastLValue(cast<CastExpr>(E)); 1662 1663 case Expr::MaterializeTemporaryExprClass: 1664 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E)); 1665 1666 case Expr::CoawaitExprClass: 1667 return EmitCoawaitLValue(cast<CoawaitExpr>(E)); 1668 case Expr::CoyieldExprClass: 1669 return EmitCoyieldLValue(cast<CoyieldExpr>(E)); 1670 case Expr::PackIndexingExprClass: 1671 return EmitLValue(cast<PackIndexingExpr>(E)->getSelectedExpr()); 1672 } 1673 } 1674 1675 /// Given an object of the given canonical type, can we safely copy a 1676 /// value out of it based on its initializer? 1677 static bool isConstantEmittableObjectType(QualType type) { 1678 assert(type.isCanonical()); 1679 assert(!type->isReferenceType()); 1680 1681 // Must be const-qualified but non-volatile. 1682 Qualifiers qs = type.getLocalQualifiers(); 1683 if (!qs.hasConst() || qs.hasVolatile()) return false; 1684 1685 // Otherwise, all object types satisfy this except C++ classes with 1686 // mutable subobjects or non-trivial copy/destroy behavior. 1687 if (const auto *RT = dyn_cast<RecordType>(type)) 1688 if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) 1689 if (RD->hasMutableFields() || !RD->isTrivial()) 1690 return false; 1691 1692 return true; 1693 } 1694 1695 /// Can we constant-emit a load of a reference to a variable of the 1696 /// given type? This is different from predicates like 1697 /// Decl::mightBeUsableInConstantExpressions because we do want it to apply 1698 /// in situations that don't necessarily satisfy the language's rules 1699 /// for this (e.g. C++'s ODR-use rules). For example, we want to able 1700 /// to do this with const float variables even if those variables 1701 /// aren't marked 'constexpr'. 1702 enum ConstantEmissionKind { 1703 CEK_None, 1704 CEK_AsReferenceOnly, 1705 CEK_AsValueOrReference, 1706 CEK_AsValueOnly 1707 }; 1708 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) { 1709 type = type.getCanonicalType(); 1710 if (const auto *ref = dyn_cast<ReferenceType>(type)) { 1711 if (isConstantEmittableObjectType(ref->getPointeeType())) 1712 return CEK_AsValueOrReference; 1713 return CEK_AsReferenceOnly; 1714 } 1715 if (isConstantEmittableObjectType(type)) 1716 return CEK_AsValueOnly; 1717 return CEK_None; 1718 } 1719 1720 /// Try to emit a reference to the given value without producing it as 1721 /// an l-value. This is just an optimization, but it avoids us needing 1722 /// to emit global copies of variables if they're named without triggering 1723 /// a formal use in a context where we can't emit a direct reference to them, 1724 /// for instance if a block or lambda or a member of a local class uses a 1725 /// const int variable or constexpr variable from an enclosing function. 1726 CodeGenFunction::ConstantEmission 1727 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) { 1728 ValueDecl *value = refExpr->getDecl(); 1729 1730 // The value needs to be an enum constant or a constant variable. 1731 ConstantEmissionKind CEK; 1732 if (isa<ParmVarDecl>(value)) { 1733 CEK = CEK_None; 1734 } else if (auto *var = dyn_cast<VarDecl>(value)) { 1735 CEK = checkVarTypeForConstantEmission(var->getType()); 1736 } else if (isa<EnumConstantDecl>(value)) { 1737 CEK = CEK_AsValueOnly; 1738 } else { 1739 CEK = CEK_None; 1740 } 1741 if (CEK == CEK_None) return ConstantEmission(); 1742 1743 Expr::EvalResult result; 1744 bool resultIsReference; 1745 QualType resultType; 1746 1747 // It's best to evaluate all the way as an r-value if that's permitted. 1748 if (CEK != CEK_AsReferenceOnly && 1749 refExpr->EvaluateAsRValue(result, getContext())) { 1750 resultIsReference = false; 1751 resultType = refExpr->getType(); 1752 1753 // Otherwise, try to evaluate as an l-value. 1754 } else if (CEK != CEK_AsValueOnly && 1755 refExpr->EvaluateAsLValue(result, getContext())) { 1756 resultIsReference = true; 1757 resultType = value->getType(); 1758 1759 // Failure. 1760 } else { 1761 return ConstantEmission(); 1762 } 1763 1764 // In any case, if the initializer has side-effects, abandon ship. 1765 if (result.HasSideEffects) 1766 return ConstantEmission(); 1767 1768 // In CUDA/HIP device compilation, a lambda may capture a reference variable 1769 // referencing a global host variable by copy. In this case the lambda should 1770 // make a copy of the value of the global host variable. The DRE of the 1771 // captured reference variable cannot be emitted as load from the host 1772 // global variable as compile time constant, since the host variable is not 1773 // accessible on device. The DRE of the captured reference variable has to be 1774 // loaded from captures. 1775 if (CGM.getLangOpts().CUDAIsDevice && result.Val.isLValue() && 1776 refExpr->refersToEnclosingVariableOrCapture()) { 1777 auto *MD = dyn_cast_or_null<CXXMethodDecl>(CurCodeDecl); 1778 if (MD && MD->getParent()->isLambda() && 1779 MD->getOverloadedOperator() == OO_Call) { 1780 const APValue::LValueBase &base = result.Val.getLValueBase(); 1781 if (const ValueDecl *D = base.dyn_cast<const ValueDecl *>()) { 1782 if (const VarDecl *VD = dyn_cast<const VarDecl>(D)) { 1783 if (!VD->hasAttr<CUDADeviceAttr>()) { 1784 return ConstantEmission(); 1785 } 1786 } 1787 } 1788 } 1789 } 1790 1791 // Emit as a constant. 1792 auto C = ConstantEmitter(*this).emitAbstract(refExpr->getLocation(), 1793 result.Val, resultType); 1794 1795 // Make sure we emit a debug reference to the global variable. 1796 // This should probably fire even for 1797 if (isa<VarDecl>(value)) { 1798 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value))) 1799 EmitDeclRefExprDbgValue(refExpr, result.Val); 1800 } else { 1801 assert(isa<EnumConstantDecl>(value)); 1802 EmitDeclRefExprDbgValue(refExpr, result.Val); 1803 } 1804 1805 // If we emitted a reference constant, we need to dereference that. 1806 if (resultIsReference) 1807 return ConstantEmission::forReference(C); 1808 1809 return ConstantEmission::forValue(C); 1810 } 1811 1812 static DeclRefExpr *tryToConvertMemberExprToDeclRefExpr(CodeGenFunction &CGF, 1813 const MemberExpr *ME) { 1814 if (auto *VD = dyn_cast<VarDecl>(ME->getMemberDecl())) { 1815 // Try to emit static variable member expressions as DREs. 1816 return DeclRefExpr::Create( 1817 CGF.getContext(), NestedNameSpecifierLoc(), SourceLocation(), VD, 1818 /*RefersToEnclosingVariableOrCapture=*/false, ME->getExprLoc(), 1819 ME->getType(), ME->getValueKind(), nullptr, nullptr, ME->isNonOdrUse()); 1820 } 1821 return nullptr; 1822 } 1823 1824 CodeGenFunction::ConstantEmission 1825 CodeGenFunction::tryEmitAsConstant(const MemberExpr *ME) { 1826 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, ME)) 1827 return tryEmitAsConstant(DRE); 1828 return ConstantEmission(); 1829 } 1830 1831 llvm::Value *CodeGenFunction::emitScalarConstant( 1832 const CodeGenFunction::ConstantEmission &Constant, Expr *E) { 1833 assert(Constant && "not a constant"); 1834 if (Constant.isReference()) 1835 return EmitLoadOfLValue(Constant.getReferenceLValue(*this, E), 1836 E->getExprLoc()) 1837 .getScalarVal(); 1838 return Constant.getValue(); 1839 } 1840 1841 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue, 1842 SourceLocation Loc) { 1843 return EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatile(), 1844 lvalue.getType(), Loc, lvalue.getBaseInfo(), 1845 lvalue.getTBAAInfo(), lvalue.isNontemporal()); 1846 } 1847 1848 static bool hasBooleanRepresentation(QualType Ty) { 1849 if (Ty->isBooleanType()) 1850 return true; 1851 1852 if (const EnumType *ET = Ty->getAs<EnumType>()) 1853 return ET->getDecl()->getIntegerType()->isBooleanType(); 1854 1855 if (const AtomicType *AT = Ty->getAs<AtomicType>()) 1856 return hasBooleanRepresentation(AT->getValueType()); 1857 1858 return false; 1859 } 1860 1861 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty, 1862 llvm::APInt &Min, llvm::APInt &End, 1863 bool StrictEnums, bool IsBool) { 1864 const EnumType *ET = Ty->getAs<EnumType>(); 1865 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums && 1866 ET && !ET->getDecl()->isFixed(); 1867 if (!IsBool && !IsRegularCPlusPlusEnum) 1868 return false; 1869 1870 if (IsBool) { 1871 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0); 1872 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2); 1873 } else { 1874 const EnumDecl *ED = ET->getDecl(); 1875 ED->getValueRange(End, Min); 1876 } 1877 return true; 1878 } 1879 1880 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) { 1881 llvm::APInt Min, End; 1882 if (!getRangeForType(*this, Ty, Min, End, CGM.getCodeGenOpts().StrictEnums, 1883 hasBooleanRepresentation(Ty))) 1884 return nullptr; 1885 1886 llvm::MDBuilder MDHelper(getLLVMContext()); 1887 return MDHelper.createRange(Min, End); 1888 } 1889 1890 bool CodeGenFunction::EmitScalarRangeCheck(llvm::Value *Value, QualType Ty, 1891 SourceLocation Loc) { 1892 bool HasBoolCheck = SanOpts.has(SanitizerKind::Bool); 1893 bool HasEnumCheck = SanOpts.has(SanitizerKind::Enum); 1894 if (!HasBoolCheck && !HasEnumCheck) 1895 return false; 1896 1897 bool IsBool = hasBooleanRepresentation(Ty) || 1898 NSAPI(CGM.getContext()).isObjCBOOLType(Ty); 1899 bool NeedsBoolCheck = HasBoolCheck && IsBool; 1900 bool NeedsEnumCheck = HasEnumCheck && Ty->getAs<EnumType>(); 1901 if (!NeedsBoolCheck && !NeedsEnumCheck) 1902 return false; 1903 1904 // Single-bit booleans don't need to be checked. Special-case this to avoid 1905 // a bit width mismatch when handling bitfield values. This is handled by 1906 // EmitFromMemory for the non-bitfield case. 1907 if (IsBool && 1908 cast<llvm::IntegerType>(Value->getType())->getBitWidth() == 1) 1909 return false; 1910 1911 llvm::APInt Min, End; 1912 if (!getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true, IsBool)) 1913 return true; 1914 1915 auto &Ctx = getLLVMContext(); 1916 SanitizerScope SanScope(this); 1917 llvm::Value *Check; 1918 --End; 1919 if (!Min) { 1920 Check = Builder.CreateICmpULE(Value, llvm::ConstantInt::get(Ctx, End)); 1921 } else { 1922 llvm::Value *Upper = 1923 Builder.CreateICmpSLE(Value, llvm::ConstantInt::get(Ctx, End)); 1924 llvm::Value *Lower = 1925 Builder.CreateICmpSGE(Value, llvm::ConstantInt::get(Ctx, Min)); 1926 Check = Builder.CreateAnd(Upper, Lower); 1927 } 1928 llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc), 1929 EmitCheckTypeDescriptor(Ty)}; 1930 SanitizerMask Kind = 1931 NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool; 1932 EmitCheck(std::make_pair(Check, Kind), SanitizerHandler::LoadInvalidValue, 1933 StaticArgs, EmitCheckValue(Value)); 1934 return true; 1935 } 1936 1937 llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile, 1938 QualType Ty, 1939 SourceLocation Loc, 1940 LValueBaseInfo BaseInfo, 1941 TBAAAccessInfo TBAAInfo, 1942 bool isNontemporal) { 1943 if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr.getBasePointer())) 1944 if (GV->isThreadLocal()) 1945 Addr = Addr.withPointer(Builder.CreateThreadLocalAddress(GV), 1946 NotKnownNonNull); 1947 1948 if (const auto *ClangVecTy = Ty->getAs<VectorType>()) { 1949 // Boolean vectors use `iN` as storage type. 1950 if (ClangVecTy->isExtVectorBoolType()) { 1951 llvm::Type *ValTy = ConvertType(Ty); 1952 unsigned ValNumElems = 1953 cast<llvm::FixedVectorType>(ValTy)->getNumElements(); 1954 // Load the `iP` storage object (P is the padded vector size). 1955 auto *RawIntV = Builder.CreateLoad(Addr, Volatile, "load_bits"); 1956 const auto *RawIntTy = RawIntV->getType(); 1957 assert(RawIntTy->isIntegerTy() && "compressed iN storage for bitvectors"); 1958 // Bitcast iP --> <P x i1>. 1959 auto *PaddedVecTy = llvm::FixedVectorType::get( 1960 Builder.getInt1Ty(), RawIntTy->getPrimitiveSizeInBits()); 1961 llvm::Value *V = Builder.CreateBitCast(RawIntV, PaddedVecTy); 1962 // Shuffle <P x i1> --> <N x i1> (N is the actual bit size). 1963 V = emitBoolVecConversion(V, ValNumElems, "extractvec"); 1964 1965 return EmitFromMemory(V, Ty); 1966 } 1967 1968 // Handle vectors of size 3 like size 4 for better performance. 1969 const llvm::Type *EltTy = Addr.getElementType(); 1970 const auto *VTy = cast<llvm::FixedVectorType>(EltTy); 1971 1972 if (!CGM.getCodeGenOpts().PreserveVec3Type && VTy->getNumElements() == 3) { 1973 1974 llvm::VectorType *vec4Ty = 1975 llvm::FixedVectorType::get(VTy->getElementType(), 4); 1976 Address Cast = Addr.withElementType(vec4Ty); 1977 // Now load value. 1978 llvm::Value *V = Builder.CreateLoad(Cast, Volatile, "loadVec4"); 1979 1980 // Shuffle vector to get vec3. 1981 V = Builder.CreateShuffleVector(V, ArrayRef<int>{0, 1, 2}, "extractVec"); 1982 return EmitFromMemory(V, Ty); 1983 } 1984 } 1985 1986 // Atomic operations have to be done on integral types. 1987 LValue AtomicLValue = 1988 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo); 1989 if (Ty->isAtomicType() || LValueIsSuitableForInlineAtomic(AtomicLValue)) { 1990 return EmitAtomicLoad(AtomicLValue, Loc).getScalarVal(); 1991 } 1992 1993 Addr = 1994 Addr.withElementType(convertTypeForLoadStore(Ty, Addr.getElementType())); 1995 1996 llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile); 1997 if (isNontemporal) { 1998 llvm::MDNode *Node = llvm::MDNode::get( 1999 Load->getContext(), llvm::ConstantAsMetadata::get(Builder.getInt32(1))); 2000 Load->setMetadata(llvm::LLVMContext::MD_nontemporal, Node); 2001 } 2002 2003 CGM.DecorateInstructionWithTBAA(Load, TBAAInfo); 2004 2005 if (EmitScalarRangeCheck(Load, Ty, Loc)) { 2006 // In order to prevent the optimizer from throwing away the check, don't 2007 // attach range metadata to the load. 2008 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0) 2009 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty)) { 2010 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo); 2011 Load->setMetadata(llvm::LLVMContext::MD_noundef, 2012 llvm::MDNode::get(getLLVMContext(), std::nullopt)); 2013 } 2014 2015 return EmitFromMemory(Load, Ty); 2016 } 2017 2018 /// Converts a scalar value from its primary IR type (as returned 2019 /// by ConvertType) to its load/store type (as returned by 2020 /// convertTypeForLoadStore). 2021 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) { 2022 if (hasBooleanRepresentation(Ty) || Ty->isBitIntType()) { 2023 llvm::Type *StoreTy = convertTypeForLoadStore(Ty, Value->getType()); 2024 bool Signed = Ty->isSignedIntegerOrEnumerationType(); 2025 return Builder.CreateIntCast(Value, StoreTy, Signed, "storedv"); 2026 } 2027 2028 if (Ty->isExtVectorBoolType()) { 2029 llvm::Type *StoreTy = convertTypeForLoadStore(Ty, Value->getType()); 2030 // Expand to the memory bit width. 2031 unsigned MemNumElems = StoreTy->getPrimitiveSizeInBits(); 2032 // <N x i1> --> <P x i1>. 2033 Value = emitBoolVecConversion(Value, MemNumElems, "insertvec"); 2034 // <P x i1> --> iP. 2035 Value = Builder.CreateBitCast(Value, StoreTy); 2036 } 2037 2038 return Value; 2039 } 2040 2041 /// Converts a scalar value from its load/store type (as returned 2042 /// by convertTypeForLoadStore) to its primary IR type (as returned 2043 /// by ConvertType). 2044 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) { 2045 if (Ty->isExtVectorBoolType()) { 2046 const auto *RawIntTy = Value->getType(); 2047 // Bitcast iP --> <P x i1>. 2048 auto *PaddedVecTy = llvm::FixedVectorType::get( 2049 Builder.getInt1Ty(), RawIntTy->getPrimitiveSizeInBits()); 2050 auto *V = Builder.CreateBitCast(Value, PaddedVecTy); 2051 // Shuffle <P x i1> --> <N x i1> (N is the actual bit size). 2052 llvm::Type *ValTy = ConvertType(Ty); 2053 unsigned ValNumElems = cast<llvm::FixedVectorType>(ValTy)->getNumElements(); 2054 return emitBoolVecConversion(V, ValNumElems, "extractvec"); 2055 } 2056 2057 if (hasBooleanRepresentation(Ty) || Ty->isBitIntType()) { 2058 llvm::Type *ResTy = ConvertType(Ty); 2059 return Builder.CreateTrunc(Value, ResTy, "loadedv"); 2060 } 2061 2062 return Value; 2063 } 2064 2065 // Convert the pointer of \p Addr to a pointer to a vector (the value type of 2066 // MatrixType), if it points to a array (the memory type of MatrixType). 2067 static RawAddress MaybeConvertMatrixAddress(RawAddress Addr, 2068 CodeGenFunction &CGF, 2069 bool IsVector = true) { 2070 auto *ArrayTy = dyn_cast<llvm::ArrayType>(Addr.getElementType()); 2071 if (ArrayTy && IsVector) { 2072 auto *VectorTy = llvm::FixedVectorType::get(ArrayTy->getElementType(), 2073 ArrayTy->getNumElements()); 2074 2075 return Addr.withElementType(VectorTy); 2076 } 2077 auto *VectorTy = dyn_cast<llvm::VectorType>(Addr.getElementType()); 2078 if (VectorTy && !IsVector) { 2079 auto *ArrayTy = llvm::ArrayType::get( 2080 VectorTy->getElementType(), 2081 cast<llvm::FixedVectorType>(VectorTy)->getNumElements()); 2082 2083 return Addr.withElementType(ArrayTy); 2084 } 2085 2086 return Addr; 2087 } 2088 2089 // Emit a store of a matrix LValue. This may require casting the original 2090 // pointer to memory address (ArrayType) to a pointer to the value type 2091 // (VectorType). 2092 static void EmitStoreOfMatrixScalar(llvm::Value *value, LValue lvalue, 2093 bool isInit, CodeGenFunction &CGF) { 2094 Address Addr = MaybeConvertMatrixAddress(lvalue.getAddress(), CGF, 2095 value->getType()->isVectorTy()); 2096 CGF.EmitStoreOfScalar(value, Addr, lvalue.isVolatile(), lvalue.getType(), 2097 lvalue.getBaseInfo(), lvalue.getTBAAInfo(), isInit, 2098 lvalue.isNontemporal()); 2099 } 2100 2101 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr, 2102 bool Volatile, QualType Ty, 2103 LValueBaseInfo BaseInfo, 2104 TBAAAccessInfo TBAAInfo, 2105 bool isInit, bool isNontemporal) { 2106 if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr.getBasePointer())) 2107 if (GV->isThreadLocal()) 2108 Addr = Addr.withPointer(Builder.CreateThreadLocalAddress(GV), 2109 NotKnownNonNull); 2110 2111 llvm::Type *SrcTy = Value->getType(); 2112 if (const auto *ClangVecTy = Ty->getAs<VectorType>()) { 2113 auto *VecTy = dyn_cast<llvm::FixedVectorType>(SrcTy); 2114 if (!CGM.getCodeGenOpts().PreserveVec3Type) { 2115 // Handle vec3 special. 2116 if (VecTy && !ClangVecTy->isExtVectorBoolType() && 2117 cast<llvm::FixedVectorType>(VecTy)->getNumElements() == 3) { 2118 // Our source is a vec3, do a shuffle vector to make it a vec4. 2119 Value = Builder.CreateShuffleVector(Value, ArrayRef<int>{0, 1, 2, -1}, 2120 "extractVec"); 2121 SrcTy = llvm::FixedVectorType::get(VecTy->getElementType(), 4); 2122 } 2123 if (Addr.getElementType() != SrcTy) { 2124 Addr = Addr.withElementType(SrcTy); 2125 } 2126 } 2127 } 2128 2129 Value = EmitToMemory(Value, Ty); 2130 2131 LValue AtomicLValue = 2132 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo); 2133 if (Ty->isAtomicType() || 2134 (!isInit && LValueIsSuitableForInlineAtomic(AtomicLValue))) { 2135 EmitAtomicStore(RValue::get(Value), AtomicLValue, isInit); 2136 return; 2137 } 2138 2139 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile); 2140 if (isNontemporal) { 2141 llvm::MDNode *Node = 2142 llvm::MDNode::get(Store->getContext(), 2143 llvm::ConstantAsMetadata::get(Builder.getInt32(1))); 2144 Store->setMetadata(llvm::LLVMContext::MD_nontemporal, Node); 2145 } 2146 2147 CGM.DecorateInstructionWithTBAA(Store, TBAAInfo); 2148 } 2149 2150 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue, 2151 bool isInit) { 2152 if (lvalue.getType()->isConstantMatrixType()) { 2153 EmitStoreOfMatrixScalar(value, lvalue, isInit, *this); 2154 return; 2155 } 2156 2157 EmitStoreOfScalar(value, lvalue.getAddress(), lvalue.isVolatile(), 2158 lvalue.getType(), lvalue.getBaseInfo(), 2159 lvalue.getTBAAInfo(), isInit, lvalue.isNontemporal()); 2160 } 2161 2162 // Emit a load of a LValue of matrix type. This may require casting the pointer 2163 // to memory address (ArrayType) to a pointer to the value type (VectorType). 2164 static RValue EmitLoadOfMatrixLValue(LValue LV, SourceLocation Loc, 2165 CodeGenFunction &CGF) { 2166 assert(LV.getType()->isConstantMatrixType()); 2167 Address Addr = MaybeConvertMatrixAddress(LV.getAddress(), CGF); 2168 LV.setAddress(Addr); 2169 return RValue::get(CGF.EmitLoadOfScalar(LV, Loc)); 2170 } 2171 2172 RValue CodeGenFunction::EmitLoadOfAnyValue(LValue LV, AggValueSlot Slot, 2173 SourceLocation Loc) { 2174 QualType Ty = LV.getType(); 2175 switch (getEvaluationKind(Ty)) { 2176 case TEK_Scalar: 2177 return EmitLoadOfLValue(LV, Loc); 2178 case TEK_Complex: 2179 return RValue::getComplex(EmitLoadOfComplex(LV, Loc)); 2180 case TEK_Aggregate: 2181 EmitAggFinalDestCopy(Ty, Slot, LV, EVK_NonRValue); 2182 return Slot.asRValue(); 2183 } 2184 llvm_unreachable("bad evaluation kind"); 2185 } 2186 2187 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this 2188 /// method emits the address of the lvalue, then loads the result as an rvalue, 2189 /// returning the rvalue. 2190 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) { 2191 if (LV.isObjCWeak()) { 2192 // load of a __weak object. 2193 Address AddrWeakObj = LV.getAddress(); 2194 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this, 2195 AddrWeakObj)); 2196 } 2197 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) { 2198 // In MRC mode, we do a load+autorelease. 2199 if (!getLangOpts().ObjCAutoRefCount) { 2200 return RValue::get(EmitARCLoadWeak(LV.getAddress())); 2201 } 2202 2203 // In ARC mode, we load retained and then consume the value. 2204 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress()); 2205 Object = EmitObjCConsumeObject(LV.getType(), Object); 2206 return RValue::get(Object); 2207 } 2208 2209 if (LV.isSimple()) { 2210 assert(!LV.getType()->isFunctionType()); 2211 2212 if (LV.getType()->isConstantMatrixType()) 2213 return EmitLoadOfMatrixLValue(LV, Loc, *this); 2214 2215 // Everything needs a load. 2216 return RValue::get(EmitLoadOfScalar(LV, Loc)); 2217 } 2218 2219 if (LV.isVectorElt()) { 2220 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddress(), 2221 LV.isVolatileQualified()); 2222 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(), 2223 "vecext")); 2224 } 2225 2226 // If this is a reference to a subset of the elements of a vector, either 2227 // shuffle the input or extract/insert them as appropriate. 2228 if (LV.isExtVectorElt()) { 2229 return EmitLoadOfExtVectorElementLValue(LV); 2230 } 2231 2232 // Global Register variables always invoke intrinsics 2233 if (LV.isGlobalReg()) 2234 return EmitLoadOfGlobalRegLValue(LV); 2235 2236 if (LV.isMatrixElt()) { 2237 llvm::Value *Idx = LV.getMatrixIdx(); 2238 if (CGM.getCodeGenOpts().OptimizationLevel > 0) { 2239 const auto *const MatTy = LV.getType()->castAs<ConstantMatrixType>(); 2240 llvm::MatrixBuilder MB(Builder); 2241 MB.CreateIndexAssumption(Idx, MatTy->getNumElementsFlattened()); 2242 } 2243 llvm::LoadInst *Load = 2244 Builder.CreateLoad(LV.getMatrixAddress(), LV.isVolatileQualified()); 2245 return RValue::get(Builder.CreateExtractElement(Load, Idx, "matrixext")); 2246 } 2247 2248 assert(LV.isBitField() && "Unknown LValue type!"); 2249 return EmitLoadOfBitfieldLValue(LV, Loc); 2250 } 2251 2252 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV, 2253 SourceLocation Loc) { 2254 const CGBitFieldInfo &Info = LV.getBitFieldInfo(); 2255 2256 // Get the output type. 2257 llvm::Type *ResLTy = ConvertType(LV.getType()); 2258 2259 Address Ptr = LV.getBitFieldAddress(); 2260 llvm::Value *Val = 2261 Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "bf.load"); 2262 2263 bool UseVolatile = LV.isVolatileQualified() && 2264 Info.VolatileStorageSize != 0 && isAAPCS(CGM.getTarget()); 2265 const unsigned Offset = UseVolatile ? Info.VolatileOffset : Info.Offset; 2266 const unsigned StorageSize = 2267 UseVolatile ? Info.VolatileStorageSize : Info.StorageSize; 2268 if (Info.IsSigned) { 2269 assert(static_cast<unsigned>(Offset + Info.Size) <= StorageSize); 2270 unsigned HighBits = StorageSize - Offset - Info.Size; 2271 if (HighBits) 2272 Val = Builder.CreateShl(Val, HighBits, "bf.shl"); 2273 if (Offset + HighBits) 2274 Val = Builder.CreateAShr(Val, Offset + HighBits, "bf.ashr"); 2275 } else { 2276 if (Offset) 2277 Val = Builder.CreateLShr(Val, Offset, "bf.lshr"); 2278 if (static_cast<unsigned>(Offset) + Info.Size < StorageSize) 2279 Val = Builder.CreateAnd( 2280 Val, llvm::APInt::getLowBitsSet(StorageSize, Info.Size), "bf.clear"); 2281 } 2282 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast"); 2283 EmitScalarRangeCheck(Val, LV.getType(), Loc); 2284 return RValue::get(Val); 2285 } 2286 2287 // If this is a reference to a subset of the elements of a vector, create an 2288 // appropriate shufflevector. 2289 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) { 2290 llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddress(), 2291 LV.isVolatileQualified()); 2292 2293 // HLSL allows treating scalars as one-element vectors. Converting the scalar 2294 // IR value to a vector here allows the rest of codegen to behave as normal. 2295 if (getLangOpts().HLSL && !Vec->getType()->isVectorTy()) { 2296 llvm::Type *DstTy = llvm::FixedVectorType::get(Vec->getType(), 1); 2297 llvm::Value *Zero = llvm::Constant::getNullValue(CGM.Int64Ty); 2298 Vec = Builder.CreateInsertElement(DstTy, Vec, Zero, "cast.splat"); 2299 } 2300 2301 const llvm::Constant *Elts = LV.getExtVectorElts(); 2302 2303 // If the result of the expression is a non-vector type, we must be extracting 2304 // a single element. Just codegen as an extractelement. 2305 const VectorType *ExprVT = LV.getType()->getAs<VectorType>(); 2306 if (!ExprVT) { 2307 unsigned InIdx = getAccessedFieldNo(0, Elts); 2308 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx); 2309 return RValue::get(Builder.CreateExtractElement(Vec, Elt)); 2310 } 2311 2312 // Always use shuffle vector to try to retain the original program structure 2313 unsigned NumResultElts = ExprVT->getNumElements(); 2314 2315 SmallVector<int, 4> Mask; 2316 for (unsigned i = 0; i != NumResultElts; ++i) 2317 Mask.push_back(getAccessedFieldNo(i, Elts)); 2318 2319 Vec = Builder.CreateShuffleVector(Vec, Mask); 2320 return RValue::get(Vec); 2321 } 2322 2323 /// Generates lvalue for partial ext_vector access. 2324 Address CodeGenFunction::EmitExtVectorElementLValue(LValue LV) { 2325 Address VectorAddress = LV.getExtVectorAddress(); 2326 QualType EQT = LV.getType()->castAs<VectorType>()->getElementType(); 2327 llvm::Type *VectorElementTy = CGM.getTypes().ConvertType(EQT); 2328 2329 Address CastToPointerElement = VectorAddress.withElementType(VectorElementTy); 2330 2331 const llvm::Constant *Elts = LV.getExtVectorElts(); 2332 unsigned ix = getAccessedFieldNo(0, Elts); 2333 2334 Address VectorBasePtrPlusIx = 2335 Builder.CreateConstInBoundsGEP(CastToPointerElement, ix, 2336 "vector.elt"); 2337 2338 return VectorBasePtrPlusIx; 2339 } 2340 2341 /// Load of global gamed gegisters are always calls to intrinsics. 2342 RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) { 2343 assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) && 2344 "Bad type for register variable"); 2345 llvm::MDNode *RegName = cast<llvm::MDNode>( 2346 cast<llvm::MetadataAsValue>(LV.getGlobalReg())->getMetadata()); 2347 2348 // We accept integer and pointer types only 2349 llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType()); 2350 llvm::Type *Ty = OrigTy; 2351 if (OrigTy->isPointerTy()) 2352 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy); 2353 llvm::Type *Types[] = { Ty }; 2354 2355 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types); 2356 llvm::Value *Call = Builder.CreateCall( 2357 F, llvm::MetadataAsValue::get(Ty->getContext(), RegName)); 2358 if (OrigTy->isPointerTy()) 2359 Call = Builder.CreateIntToPtr(Call, OrigTy); 2360 return RValue::get(Call); 2361 } 2362 2363 /// EmitStoreThroughLValue - Store the specified rvalue into the specified 2364 /// lvalue, where both are guaranteed to the have the same type, and that type 2365 /// is 'Ty'. 2366 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst, 2367 bool isInit) { 2368 if (!Dst.isSimple()) { 2369 if (Dst.isVectorElt()) { 2370 // Read/modify/write the vector, inserting the new element. 2371 llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddress(), 2372 Dst.isVolatileQualified()); 2373 auto *IRStoreTy = dyn_cast<llvm::IntegerType>(Vec->getType()); 2374 if (IRStoreTy) { 2375 auto *IRVecTy = llvm::FixedVectorType::get( 2376 Builder.getInt1Ty(), IRStoreTy->getPrimitiveSizeInBits()); 2377 Vec = Builder.CreateBitCast(Vec, IRVecTy); 2378 // iN --> <N x i1>. 2379 } 2380 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(), 2381 Dst.getVectorIdx(), "vecins"); 2382 if (IRStoreTy) { 2383 // <N x i1> --> <iN>. 2384 Vec = Builder.CreateBitCast(Vec, IRStoreTy); 2385 } 2386 Builder.CreateStore(Vec, Dst.getVectorAddress(), 2387 Dst.isVolatileQualified()); 2388 return; 2389 } 2390 2391 // If this is an update of extended vector elements, insert them as 2392 // appropriate. 2393 if (Dst.isExtVectorElt()) 2394 return EmitStoreThroughExtVectorComponentLValue(Src, Dst); 2395 2396 if (Dst.isGlobalReg()) 2397 return EmitStoreThroughGlobalRegLValue(Src, Dst); 2398 2399 if (Dst.isMatrixElt()) { 2400 llvm::Value *Idx = Dst.getMatrixIdx(); 2401 if (CGM.getCodeGenOpts().OptimizationLevel > 0) { 2402 const auto *const MatTy = Dst.getType()->castAs<ConstantMatrixType>(); 2403 llvm::MatrixBuilder MB(Builder); 2404 MB.CreateIndexAssumption(Idx, MatTy->getNumElementsFlattened()); 2405 } 2406 llvm::Instruction *Load = Builder.CreateLoad(Dst.getMatrixAddress()); 2407 llvm::Value *Vec = 2408 Builder.CreateInsertElement(Load, Src.getScalarVal(), Idx, "matins"); 2409 Builder.CreateStore(Vec, Dst.getMatrixAddress(), 2410 Dst.isVolatileQualified()); 2411 return; 2412 } 2413 2414 assert(Dst.isBitField() && "Unknown LValue type"); 2415 return EmitStoreThroughBitfieldLValue(Src, Dst); 2416 } 2417 2418 // There's special magic for assigning into an ARC-qualified l-value. 2419 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) { 2420 switch (Lifetime) { 2421 case Qualifiers::OCL_None: 2422 llvm_unreachable("present but none"); 2423 2424 case Qualifiers::OCL_ExplicitNone: 2425 // nothing special 2426 break; 2427 2428 case Qualifiers::OCL_Strong: 2429 if (isInit) { 2430 Src = RValue::get(EmitARCRetain(Dst.getType(), Src.getScalarVal())); 2431 break; 2432 } 2433 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true); 2434 return; 2435 2436 case Qualifiers::OCL_Weak: 2437 if (isInit) 2438 // Initialize and then skip the primitive store. 2439 EmitARCInitWeak(Dst.getAddress(), Src.getScalarVal()); 2440 else 2441 EmitARCStoreWeak(Dst.getAddress(), Src.getScalarVal(), 2442 /*ignore*/ true); 2443 return; 2444 2445 case Qualifiers::OCL_Autoreleasing: 2446 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(), 2447 Src.getScalarVal())); 2448 // fall into the normal path 2449 break; 2450 } 2451 } 2452 2453 if (Dst.isObjCWeak() && !Dst.isNonGC()) { 2454 // load of a __weak object. 2455 Address LvalueDst = Dst.getAddress(); 2456 llvm::Value *src = Src.getScalarVal(); 2457 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst); 2458 return; 2459 } 2460 2461 if (Dst.isObjCStrong() && !Dst.isNonGC()) { 2462 // load of a __strong object. 2463 Address LvalueDst = Dst.getAddress(); 2464 llvm::Value *src = Src.getScalarVal(); 2465 if (Dst.isObjCIvar()) { 2466 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL"); 2467 llvm::Type *ResultType = IntPtrTy; 2468 Address dst = EmitPointerWithAlignment(Dst.getBaseIvarExp()); 2469 llvm::Value *RHS = dst.emitRawPointer(*this); 2470 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast"); 2471 llvm::Value *LHS = Builder.CreatePtrToInt(LvalueDst.emitRawPointer(*this), 2472 ResultType, "sub.ptr.lhs.cast"); 2473 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset"); 2474 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst, BytesBetween); 2475 } else if (Dst.isGlobalObjCRef()) { 2476 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst, 2477 Dst.isThreadLocalRef()); 2478 } 2479 else 2480 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst); 2481 return; 2482 } 2483 2484 assert(Src.isScalar() && "Can't emit an agg store with this method"); 2485 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit); 2486 } 2487 2488 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst, 2489 llvm::Value **Result) { 2490 const CGBitFieldInfo &Info = Dst.getBitFieldInfo(); 2491 llvm::Type *ResLTy = convertTypeForLoadStore(Dst.getType()); 2492 Address Ptr = Dst.getBitFieldAddress(); 2493 2494 // Get the source value, truncated to the width of the bit-field. 2495 llvm::Value *SrcVal = Src.getScalarVal(); 2496 2497 // Cast the source to the storage type and shift it into place. 2498 SrcVal = Builder.CreateIntCast(SrcVal, Ptr.getElementType(), 2499 /*isSigned=*/false); 2500 llvm::Value *MaskedVal = SrcVal; 2501 2502 const bool UseVolatile = 2503 CGM.getCodeGenOpts().AAPCSBitfieldWidth && Dst.isVolatileQualified() && 2504 Info.VolatileStorageSize != 0 && isAAPCS(CGM.getTarget()); 2505 const unsigned StorageSize = 2506 UseVolatile ? Info.VolatileStorageSize : Info.StorageSize; 2507 const unsigned Offset = UseVolatile ? Info.VolatileOffset : Info.Offset; 2508 // See if there are other bits in the bitfield's storage we'll need to load 2509 // and mask together with source before storing. 2510 if (StorageSize != Info.Size) { 2511 assert(StorageSize > Info.Size && "Invalid bitfield size."); 2512 llvm::Value *Val = 2513 Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.load"); 2514 2515 // Mask the source value as needed. 2516 if (!hasBooleanRepresentation(Dst.getType())) 2517 SrcVal = Builder.CreateAnd( 2518 SrcVal, llvm::APInt::getLowBitsSet(StorageSize, Info.Size), 2519 "bf.value"); 2520 MaskedVal = SrcVal; 2521 if (Offset) 2522 SrcVal = Builder.CreateShl(SrcVal, Offset, "bf.shl"); 2523 2524 // Mask out the original value. 2525 Val = Builder.CreateAnd( 2526 Val, ~llvm::APInt::getBitsSet(StorageSize, Offset, Offset + Info.Size), 2527 "bf.clear"); 2528 2529 // Or together the unchanged values and the source value. 2530 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set"); 2531 } else { 2532 assert(Offset == 0); 2533 // According to the AACPS: 2534 // When a volatile bit-field is written, and its container does not overlap 2535 // with any non-bit-field member, its container must be read exactly once 2536 // and written exactly once using the access width appropriate to the type 2537 // of the container. The two accesses are not atomic. 2538 if (Dst.isVolatileQualified() && isAAPCS(CGM.getTarget()) && 2539 CGM.getCodeGenOpts().ForceAAPCSBitfieldLoad) 2540 Builder.CreateLoad(Ptr, true, "bf.load"); 2541 } 2542 2543 // Write the new value back out. 2544 Builder.CreateStore(SrcVal, Ptr, Dst.isVolatileQualified()); 2545 2546 // Return the new value of the bit-field, if requested. 2547 if (Result) { 2548 llvm::Value *ResultVal = MaskedVal; 2549 2550 // Sign extend the value if needed. 2551 if (Info.IsSigned) { 2552 assert(Info.Size <= StorageSize); 2553 unsigned HighBits = StorageSize - Info.Size; 2554 if (HighBits) { 2555 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl"); 2556 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr"); 2557 } 2558 } 2559 2560 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned, 2561 "bf.result.cast"); 2562 *Result = EmitFromMemory(ResultVal, Dst.getType()); 2563 } 2564 } 2565 2566 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src, 2567 LValue Dst) { 2568 // HLSL allows storing to scalar values through ExtVector component LValues. 2569 // To support this we need to handle the case where the destination address is 2570 // a scalar. 2571 Address DstAddr = Dst.getExtVectorAddress(); 2572 if (!DstAddr.getElementType()->isVectorTy()) { 2573 assert(!Dst.getType()->isVectorType() && 2574 "this should only occur for non-vector l-values"); 2575 Builder.CreateStore(Src.getScalarVal(), DstAddr, Dst.isVolatileQualified()); 2576 return; 2577 } 2578 2579 // This access turns into a read/modify/write of the vector. Load the input 2580 // value now. 2581 llvm::Value *Vec = Builder.CreateLoad(DstAddr, Dst.isVolatileQualified()); 2582 const llvm::Constant *Elts = Dst.getExtVectorElts(); 2583 2584 llvm::Value *SrcVal = Src.getScalarVal(); 2585 2586 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) { 2587 unsigned NumSrcElts = VTy->getNumElements(); 2588 unsigned NumDstElts = 2589 cast<llvm::FixedVectorType>(Vec->getType())->getNumElements(); 2590 if (NumDstElts == NumSrcElts) { 2591 // Use shuffle vector is the src and destination are the same number of 2592 // elements and restore the vector mask since it is on the side it will be 2593 // stored. 2594 SmallVector<int, 4> Mask(NumDstElts); 2595 for (unsigned i = 0; i != NumSrcElts; ++i) 2596 Mask[getAccessedFieldNo(i, Elts)] = i; 2597 2598 Vec = Builder.CreateShuffleVector(SrcVal, Mask); 2599 } else if (NumDstElts > NumSrcElts) { 2600 // Extended the source vector to the same length and then shuffle it 2601 // into the destination. 2602 // FIXME: since we're shuffling with undef, can we just use the indices 2603 // into that? This could be simpler. 2604 SmallVector<int, 4> ExtMask; 2605 for (unsigned i = 0; i != NumSrcElts; ++i) 2606 ExtMask.push_back(i); 2607 ExtMask.resize(NumDstElts, -1); 2608 llvm::Value *ExtSrcVal = Builder.CreateShuffleVector(SrcVal, ExtMask); 2609 // build identity 2610 SmallVector<int, 4> Mask; 2611 for (unsigned i = 0; i != NumDstElts; ++i) 2612 Mask.push_back(i); 2613 2614 // When the vector size is odd and .odd or .hi is used, the last element 2615 // of the Elts constant array will be one past the size of the vector. 2616 // Ignore the last element here, if it is greater than the mask size. 2617 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size()) 2618 NumSrcElts--; 2619 2620 // modify when what gets shuffled in 2621 for (unsigned i = 0; i != NumSrcElts; ++i) 2622 Mask[getAccessedFieldNo(i, Elts)] = i + NumDstElts; 2623 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, Mask); 2624 } else { 2625 // We should never shorten the vector 2626 llvm_unreachable("unexpected shorten vector length"); 2627 } 2628 } else { 2629 // If the Src is a scalar (not a vector), and the target is a vector it must 2630 // be updating one element. 2631 unsigned InIdx = getAccessedFieldNo(0, Elts); 2632 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx); 2633 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt); 2634 } 2635 2636 Builder.CreateStore(Vec, Dst.getExtVectorAddress(), 2637 Dst.isVolatileQualified()); 2638 } 2639 2640 /// Store of global named registers are always calls to intrinsics. 2641 void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) { 2642 assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) && 2643 "Bad type for register variable"); 2644 llvm::MDNode *RegName = cast<llvm::MDNode>( 2645 cast<llvm::MetadataAsValue>(Dst.getGlobalReg())->getMetadata()); 2646 assert(RegName && "Register LValue is not metadata"); 2647 2648 // We accept integer and pointer types only 2649 llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType()); 2650 llvm::Type *Ty = OrigTy; 2651 if (OrigTy->isPointerTy()) 2652 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy); 2653 llvm::Type *Types[] = { Ty }; 2654 2655 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types); 2656 llvm::Value *Value = Src.getScalarVal(); 2657 if (OrigTy->isPointerTy()) 2658 Value = Builder.CreatePtrToInt(Value, Ty); 2659 Builder.CreateCall( 2660 F, {llvm::MetadataAsValue::get(Ty->getContext(), RegName), Value}); 2661 } 2662 2663 // setObjCGCLValueClass - sets class of the lvalue for the purpose of 2664 // generating write-barries API. It is currently a global, ivar, 2665 // or neither. 2666 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E, 2667 LValue &LV, 2668 bool IsMemberAccess=false) { 2669 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC) 2670 return; 2671 2672 if (isa<ObjCIvarRefExpr>(E)) { 2673 QualType ExpTy = E->getType(); 2674 if (IsMemberAccess && ExpTy->isPointerType()) { 2675 // If ivar is a structure pointer, assigning to field of 2676 // this struct follows gcc's behavior and makes it a non-ivar 2677 // writer-barrier conservatively. 2678 ExpTy = ExpTy->castAs<PointerType>()->getPointeeType(); 2679 if (ExpTy->isRecordType()) { 2680 LV.setObjCIvar(false); 2681 return; 2682 } 2683 } 2684 LV.setObjCIvar(true); 2685 auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E)); 2686 LV.setBaseIvarExp(Exp->getBase()); 2687 LV.setObjCArray(E->getType()->isArrayType()); 2688 return; 2689 } 2690 2691 if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) { 2692 if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) { 2693 if (VD->hasGlobalStorage()) { 2694 LV.setGlobalObjCRef(true); 2695 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None); 2696 } 2697 } 2698 LV.setObjCArray(E->getType()->isArrayType()); 2699 return; 2700 } 2701 2702 if (const auto *Exp = dyn_cast<UnaryOperator>(E)) { 2703 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2704 return; 2705 } 2706 2707 if (const auto *Exp = dyn_cast<ParenExpr>(E)) { 2708 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2709 if (LV.isObjCIvar()) { 2710 // If cast is to a structure pointer, follow gcc's behavior and make it 2711 // a non-ivar write-barrier. 2712 QualType ExpTy = E->getType(); 2713 if (ExpTy->isPointerType()) 2714 ExpTy = ExpTy->castAs<PointerType>()->getPointeeType(); 2715 if (ExpTy->isRecordType()) 2716 LV.setObjCIvar(false); 2717 } 2718 return; 2719 } 2720 2721 if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) { 2722 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV); 2723 return; 2724 } 2725 2726 if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) { 2727 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2728 return; 2729 } 2730 2731 if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) { 2732 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2733 return; 2734 } 2735 2736 if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) { 2737 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess); 2738 return; 2739 } 2740 2741 if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) { 2742 setObjCGCLValueClass(Ctx, Exp->getBase(), LV); 2743 if (LV.isObjCIvar() && !LV.isObjCArray()) 2744 // Using array syntax to assigning to what an ivar points to is not 2745 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0; 2746 LV.setObjCIvar(false); 2747 else if (LV.isGlobalObjCRef() && !LV.isObjCArray()) 2748 // Using array syntax to assigning to what global points to is not 2749 // same as assigning to the global itself. {id *G;} G[i] = 0; 2750 LV.setGlobalObjCRef(false); 2751 return; 2752 } 2753 2754 if (const auto *Exp = dyn_cast<MemberExpr>(E)) { 2755 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true); 2756 // We don't know if member is an 'ivar', but this flag is looked at 2757 // only in the context of LV.isObjCIvar(). 2758 LV.setObjCArray(E->getType()->isArrayType()); 2759 return; 2760 } 2761 } 2762 2763 static LValue EmitThreadPrivateVarDeclLValue( 2764 CodeGenFunction &CGF, const VarDecl *VD, QualType T, Address Addr, 2765 llvm::Type *RealVarTy, SourceLocation Loc) { 2766 if (CGF.CGM.getLangOpts().OpenMPIRBuilder) 2767 Addr = CodeGenFunction::OMPBuilderCBHelpers::getAddrOfThreadPrivate( 2768 CGF, VD, Addr, Loc); 2769 else 2770 Addr = 2771 CGF.CGM.getOpenMPRuntime().getAddrOfThreadPrivate(CGF, VD, Addr, Loc); 2772 2773 Addr = Addr.withElementType(RealVarTy); 2774 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl); 2775 } 2776 2777 static Address emitDeclTargetVarDeclLValue(CodeGenFunction &CGF, 2778 const VarDecl *VD, QualType T) { 2779 std::optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res = 2780 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD); 2781 // Return an invalid address if variable is MT_To (or MT_Enter starting with 2782 // OpenMP 5.2) and unified memory is not enabled. For all other cases: MT_Link 2783 // and MT_To (or MT_Enter) with unified memory, return a valid address. 2784 if (!Res || ((*Res == OMPDeclareTargetDeclAttr::MT_To || 2785 *Res == OMPDeclareTargetDeclAttr::MT_Enter) && 2786 !CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory())) 2787 return Address::invalid(); 2788 assert(((*Res == OMPDeclareTargetDeclAttr::MT_Link) || 2789 ((*Res == OMPDeclareTargetDeclAttr::MT_To || 2790 *Res == OMPDeclareTargetDeclAttr::MT_Enter) && 2791 CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory())) && 2792 "Expected link clause OR to clause with unified memory enabled."); 2793 QualType PtrTy = CGF.getContext().getPointerType(VD->getType()); 2794 Address Addr = CGF.CGM.getOpenMPRuntime().getAddrOfDeclareTargetVar(VD); 2795 return CGF.EmitLoadOfPointer(Addr, PtrTy->castAs<PointerType>()); 2796 } 2797 2798 Address 2799 CodeGenFunction::EmitLoadOfReference(LValue RefLVal, 2800 LValueBaseInfo *PointeeBaseInfo, 2801 TBAAAccessInfo *PointeeTBAAInfo) { 2802 llvm::LoadInst *Load = 2803 Builder.CreateLoad(RefLVal.getAddress(), RefLVal.isVolatile()); 2804 CGM.DecorateInstructionWithTBAA(Load, RefLVal.getTBAAInfo()); 2805 return makeNaturalAddressForPointer(Load, RefLVal.getType()->getPointeeType(), 2806 CharUnits(), /*ForPointeeType=*/true, 2807 PointeeBaseInfo, PointeeTBAAInfo); 2808 } 2809 2810 LValue CodeGenFunction::EmitLoadOfReferenceLValue(LValue RefLVal) { 2811 LValueBaseInfo PointeeBaseInfo; 2812 TBAAAccessInfo PointeeTBAAInfo; 2813 Address PointeeAddr = EmitLoadOfReference(RefLVal, &PointeeBaseInfo, 2814 &PointeeTBAAInfo); 2815 return MakeAddrLValue(PointeeAddr, RefLVal.getType()->getPointeeType(), 2816 PointeeBaseInfo, PointeeTBAAInfo); 2817 } 2818 2819 Address CodeGenFunction::EmitLoadOfPointer(Address Ptr, 2820 const PointerType *PtrTy, 2821 LValueBaseInfo *BaseInfo, 2822 TBAAAccessInfo *TBAAInfo) { 2823 llvm::Value *Addr = Builder.CreateLoad(Ptr); 2824 return makeNaturalAddressForPointer(Addr, PtrTy->getPointeeType(), 2825 CharUnits(), /*ForPointeeType=*/true, 2826 BaseInfo, TBAAInfo); 2827 } 2828 2829 LValue CodeGenFunction::EmitLoadOfPointerLValue(Address PtrAddr, 2830 const PointerType *PtrTy) { 2831 LValueBaseInfo BaseInfo; 2832 TBAAAccessInfo TBAAInfo; 2833 Address Addr = EmitLoadOfPointer(PtrAddr, PtrTy, &BaseInfo, &TBAAInfo); 2834 return MakeAddrLValue(Addr, PtrTy->getPointeeType(), BaseInfo, TBAAInfo); 2835 } 2836 2837 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF, 2838 const Expr *E, const VarDecl *VD) { 2839 QualType T = E->getType(); 2840 2841 // If it's thread_local, emit a call to its wrapper function instead. 2842 if (VD->getTLSKind() == VarDecl::TLS_Dynamic && 2843 CGF.CGM.getCXXABI().usesThreadWrapperFunction(VD)) 2844 return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T); 2845 // Check if the variable is marked as declare target with link clause in 2846 // device codegen. 2847 if (CGF.getLangOpts().OpenMPIsTargetDevice) { 2848 Address Addr = emitDeclTargetVarDeclLValue(CGF, VD, T); 2849 if (Addr.isValid()) 2850 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl); 2851 } 2852 2853 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD); 2854 2855 if (VD->getTLSKind() != VarDecl::TLS_None) 2856 V = CGF.Builder.CreateThreadLocalAddress(V); 2857 2858 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType()); 2859 CharUnits Alignment = CGF.getContext().getDeclAlign(VD); 2860 Address Addr(V, RealVarTy, Alignment); 2861 // Emit reference to the private copy of the variable if it is an OpenMP 2862 // threadprivate variable. 2863 if (CGF.getLangOpts().OpenMP && !CGF.getLangOpts().OpenMPSimd && 2864 VD->hasAttr<OMPThreadPrivateDeclAttr>()) { 2865 return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy, 2866 E->getExprLoc()); 2867 } 2868 LValue LV = VD->getType()->isReferenceType() ? 2869 CGF.EmitLoadOfReferenceLValue(Addr, VD->getType(), 2870 AlignmentSource::Decl) : 2871 CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl); 2872 setObjCGCLValueClass(CGF.getContext(), E, LV); 2873 return LV; 2874 } 2875 2876 llvm::Constant *CodeGenModule::getRawFunctionPointer(GlobalDecl GD, 2877 llvm::Type *Ty) { 2878 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 2879 if (FD->hasAttr<WeakRefAttr>()) { 2880 ConstantAddress aliasee = GetWeakRefReference(FD); 2881 return aliasee.getPointer(); 2882 } 2883 2884 llvm::Constant *V = GetAddrOfFunction(GD, Ty); 2885 return V; 2886 } 2887 2888 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF, const Expr *E, 2889 GlobalDecl GD) { 2890 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 2891 llvm::Constant *V = CGF.CGM.getFunctionPointer(GD); 2892 CharUnits Alignment = CGF.getContext().getDeclAlign(FD); 2893 return CGF.MakeAddrLValue(V, E->getType(), Alignment, 2894 AlignmentSource::Decl); 2895 } 2896 2897 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD, 2898 llvm::Value *ThisValue) { 2899 2900 return CGF.EmitLValueForLambdaField(FD, ThisValue); 2901 } 2902 2903 /// Named Registers are named metadata pointing to the register name 2904 /// which will be read from/written to as an argument to the intrinsic 2905 /// @llvm.read/write_register. 2906 /// So far, only the name is being passed down, but other options such as 2907 /// register type, allocation type or even optimization options could be 2908 /// passed down via the metadata node. 2909 static LValue EmitGlobalNamedRegister(const VarDecl *VD, CodeGenModule &CGM) { 2910 SmallString<64> Name("llvm.named.register."); 2911 AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>(); 2912 assert(Asm->getLabel().size() < 64-Name.size() && 2913 "Register name too big"); 2914 Name.append(Asm->getLabel()); 2915 llvm::NamedMDNode *M = 2916 CGM.getModule().getOrInsertNamedMetadata(Name); 2917 if (M->getNumOperands() == 0) { 2918 llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(), 2919 Asm->getLabel()); 2920 llvm::Metadata *Ops[] = {Str}; 2921 M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops)); 2922 } 2923 2924 CharUnits Alignment = CGM.getContext().getDeclAlign(VD); 2925 2926 llvm::Value *Ptr = 2927 llvm::MetadataAsValue::get(CGM.getLLVMContext(), M->getOperand(0)); 2928 return LValue::MakeGlobalReg(Ptr, Alignment, VD->getType()); 2929 } 2930 2931 /// Determine whether we can emit a reference to \p VD from the current 2932 /// context, despite not necessarily having seen an odr-use of the variable in 2933 /// this context. 2934 static bool canEmitSpuriousReferenceToVariable(CodeGenFunction &CGF, 2935 const DeclRefExpr *E, 2936 const VarDecl *VD) { 2937 // For a variable declared in an enclosing scope, do not emit a spurious 2938 // reference even if we have a capture, as that will emit an unwarranted 2939 // reference to our capture state, and will likely generate worse code than 2940 // emitting a local copy. 2941 if (E->refersToEnclosingVariableOrCapture()) 2942 return false; 2943 2944 // For a local declaration declared in this function, we can always reference 2945 // it even if we don't have an odr-use. 2946 if (VD->hasLocalStorage()) { 2947 return VD->getDeclContext() == 2948 dyn_cast_or_null<DeclContext>(CGF.CurCodeDecl); 2949 } 2950 2951 // For a global declaration, we can emit a reference to it if we know 2952 // for sure that we are able to emit a definition of it. 2953 VD = VD->getDefinition(CGF.getContext()); 2954 if (!VD) 2955 return false; 2956 2957 // Don't emit a spurious reference if it might be to a variable that only 2958 // exists on a different device / target. 2959 // FIXME: This is unnecessarily broad. Check whether this would actually be a 2960 // cross-target reference. 2961 if (CGF.getLangOpts().OpenMP || CGF.getLangOpts().CUDA || 2962 CGF.getLangOpts().OpenCL) { 2963 return false; 2964 } 2965 2966 // We can emit a spurious reference only if the linkage implies that we'll 2967 // be emitting a non-interposable symbol that will be retained until link 2968 // time. 2969 switch (CGF.CGM.getLLVMLinkageVarDefinition(VD)) { 2970 case llvm::GlobalValue::ExternalLinkage: 2971 case llvm::GlobalValue::LinkOnceODRLinkage: 2972 case llvm::GlobalValue::WeakODRLinkage: 2973 case llvm::GlobalValue::InternalLinkage: 2974 case llvm::GlobalValue::PrivateLinkage: 2975 return true; 2976 default: 2977 return false; 2978 } 2979 } 2980 2981 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) { 2982 const NamedDecl *ND = E->getDecl(); 2983 QualType T = E->getType(); 2984 2985 assert(E->isNonOdrUse() != NOUR_Unevaluated && 2986 "should not emit an unevaluated operand"); 2987 2988 if (const auto *VD = dyn_cast<VarDecl>(ND)) { 2989 // Global Named registers access via intrinsics only 2990 if (VD->getStorageClass() == SC_Register && 2991 VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl()) 2992 return EmitGlobalNamedRegister(VD, CGM); 2993 2994 // If this DeclRefExpr does not constitute an odr-use of the variable, 2995 // we're not permitted to emit a reference to it in general, and it might 2996 // not be captured if capture would be necessary for a use. Emit the 2997 // constant value directly instead. 2998 if (E->isNonOdrUse() == NOUR_Constant && 2999 (VD->getType()->isReferenceType() || 3000 !canEmitSpuriousReferenceToVariable(*this, E, VD))) { 3001 VD->getAnyInitializer(VD); 3002 llvm::Constant *Val = ConstantEmitter(*this).emitAbstract( 3003 E->getLocation(), *VD->evaluateValue(), VD->getType()); 3004 assert(Val && "failed to emit constant expression"); 3005 3006 Address Addr = Address::invalid(); 3007 if (!VD->getType()->isReferenceType()) { 3008 // Spill the constant value to a global. 3009 Addr = CGM.createUnnamedGlobalFrom(*VD, Val, 3010 getContext().getDeclAlign(VD)); 3011 llvm::Type *VarTy = getTypes().ConvertTypeForMem(VD->getType()); 3012 auto *PTy = llvm::PointerType::get( 3013 VarTy, getTypes().getTargetAddressSpace(VD->getType())); 3014 Addr = Builder.CreatePointerBitCastOrAddrSpaceCast(Addr, PTy, VarTy); 3015 } else { 3016 // Should we be using the alignment of the constant pointer we emitted? 3017 CharUnits Alignment = 3018 CGM.getNaturalTypeAlignment(E->getType(), 3019 /* BaseInfo= */ nullptr, 3020 /* TBAAInfo= */ nullptr, 3021 /* forPointeeType= */ true); 3022 Addr = makeNaturalAddressForPointer(Val, T, Alignment); 3023 } 3024 return MakeAddrLValue(Addr, T, AlignmentSource::Decl); 3025 } 3026 3027 // FIXME: Handle other kinds of non-odr-use DeclRefExprs. 3028 3029 // Check for captured variables. 3030 if (E->refersToEnclosingVariableOrCapture()) { 3031 VD = VD->getCanonicalDecl(); 3032 if (auto *FD = LambdaCaptureFields.lookup(VD)) 3033 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue); 3034 if (CapturedStmtInfo) { 3035 auto I = LocalDeclMap.find(VD); 3036 if (I != LocalDeclMap.end()) { 3037 LValue CapLVal; 3038 if (VD->getType()->isReferenceType()) 3039 CapLVal = EmitLoadOfReferenceLValue(I->second, VD->getType(), 3040 AlignmentSource::Decl); 3041 else 3042 CapLVal = MakeAddrLValue(I->second, T); 3043 // Mark lvalue as nontemporal if the variable is marked as nontemporal 3044 // in simd context. 3045 if (getLangOpts().OpenMP && 3046 CGM.getOpenMPRuntime().isNontemporalDecl(VD)) 3047 CapLVal.setNontemporal(/*Value=*/true); 3048 return CapLVal; 3049 } 3050 LValue CapLVal = 3051 EmitCapturedFieldLValue(*this, CapturedStmtInfo->lookup(VD), 3052 CapturedStmtInfo->getContextValue()); 3053 Address LValueAddress = CapLVal.getAddress(); 3054 CapLVal = MakeAddrLValue(Address(LValueAddress.emitRawPointer(*this), 3055 LValueAddress.getElementType(), 3056 getContext().getDeclAlign(VD)), 3057 CapLVal.getType(), 3058 LValueBaseInfo(AlignmentSource::Decl), 3059 CapLVal.getTBAAInfo()); 3060 // Mark lvalue as nontemporal if the variable is marked as nontemporal 3061 // in simd context. 3062 if (getLangOpts().OpenMP && 3063 CGM.getOpenMPRuntime().isNontemporalDecl(VD)) 3064 CapLVal.setNontemporal(/*Value=*/true); 3065 return CapLVal; 3066 } 3067 3068 assert(isa<BlockDecl>(CurCodeDecl)); 3069 Address addr = GetAddrOfBlockDecl(VD); 3070 return MakeAddrLValue(addr, T, AlignmentSource::Decl); 3071 } 3072 } 3073 3074 // FIXME: We should be able to assert this for FunctionDecls as well! 3075 // FIXME: We should be able to assert this for all DeclRefExprs, not just 3076 // those with a valid source location. 3077 assert((ND->isUsed(false) || !isa<VarDecl>(ND) || E->isNonOdrUse() || 3078 !E->getLocation().isValid()) && 3079 "Should not use decl without marking it used!"); 3080 3081 if (ND->hasAttr<WeakRefAttr>()) { 3082 const auto *VD = cast<ValueDecl>(ND); 3083 ConstantAddress Aliasee = CGM.GetWeakRefReference(VD); 3084 return MakeAddrLValue(Aliasee, T, AlignmentSource::Decl); 3085 } 3086 3087 if (const auto *VD = dyn_cast<VarDecl>(ND)) { 3088 // Check if this is a global variable. 3089 if (VD->hasLinkage() || VD->isStaticDataMember()) 3090 return EmitGlobalVarDeclLValue(*this, E, VD); 3091 3092 Address addr = Address::invalid(); 3093 3094 // The variable should generally be present in the local decl map. 3095 auto iter = LocalDeclMap.find(VD); 3096 if (iter != LocalDeclMap.end()) { 3097 addr = iter->second; 3098 3099 // Otherwise, it might be static local we haven't emitted yet for 3100 // some reason; most likely, because it's in an outer function. 3101 } else if (VD->isStaticLocal()) { 3102 llvm::Constant *var = CGM.getOrCreateStaticVarDecl( 3103 *VD, CGM.getLLVMLinkageVarDefinition(VD)); 3104 addr = Address( 3105 var, ConvertTypeForMem(VD->getType()), getContext().getDeclAlign(VD)); 3106 3107 // No other cases for now. 3108 } else { 3109 llvm_unreachable("DeclRefExpr for Decl not entered in LocalDeclMap?"); 3110 } 3111 3112 // Handle threadlocal function locals. 3113 if (VD->getTLSKind() != VarDecl::TLS_None) 3114 addr = addr.withPointer( 3115 Builder.CreateThreadLocalAddress(addr.getBasePointer()), 3116 NotKnownNonNull); 3117 3118 // Check for OpenMP threadprivate variables. 3119 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd && 3120 VD->hasAttr<OMPThreadPrivateDeclAttr>()) { 3121 return EmitThreadPrivateVarDeclLValue( 3122 *this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()), 3123 E->getExprLoc()); 3124 } 3125 3126 // Drill into block byref variables. 3127 bool isBlockByref = VD->isEscapingByref(); 3128 if (isBlockByref) { 3129 addr = emitBlockByrefAddress(addr, VD); 3130 } 3131 3132 // Drill into reference types. 3133 LValue LV = VD->getType()->isReferenceType() ? 3134 EmitLoadOfReferenceLValue(addr, VD->getType(), AlignmentSource::Decl) : 3135 MakeAddrLValue(addr, T, AlignmentSource::Decl); 3136 3137 bool isLocalStorage = VD->hasLocalStorage(); 3138 3139 bool NonGCable = isLocalStorage && 3140 !VD->getType()->isReferenceType() && 3141 !isBlockByref; 3142 if (NonGCable) { 3143 LV.getQuals().removeObjCGCAttr(); 3144 LV.setNonGC(true); 3145 } 3146 3147 bool isImpreciseLifetime = 3148 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>()); 3149 if (isImpreciseLifetime) 3150 LV.setARCPreciseLifetime(ARCImpreciseLifetime); 3151 setObjCGCLValueClass(getContext(), E, LV); 3152 return LV; 3153 } 3154 3155 if (const auto *FD = dyn_cast<FunctionDecl>(ND)) 3156 return EmitFunctionDeclLValue(*this, E, FD); 3157 3158 // FIXME: While we're emitting a binding from an enclosing scope, all other 3159 // DeclRefExprs we see should be implicitly treated as if they also refer to 3160 // an enclosing scope. 3161 if (const auto *BD = dyn_cast<BindingDecl>(ND)) { 3162 if (E->refersToEnclosingVariableOrCapture()) { 3163 auto *FD = LambdaCaptureFields.lookup(BD); 3164 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue); 3165 } 3166 return EmitLValue(BD->getBinding()); 3167 } 3168 3169 // We can form DeclRefExprs naming GUID declarations when reconstituting 3170 // non-type template parameters into expressions. 3171 if (const auto *GD = dyn_cast<MSGuidDecl>(ND)) 3172 return MakeAddrLValue(CGM.GetAddrOfMSGuidDecl(GD), T, 3173 AlignmentSource::Decl); 3174 3175 if (const auto *TPO = dyn_cast<TemplateParamObjectDecl>(ND)) { 3176 auto ATPO = CGM.GetAddrOfTemplateParamObject(TPO); 3177 auto AS = getLangASFromTargetAS(ATPO.getAddressSpace()); 3178 3179 if (AS != T.getAddressSpace()) { 3180 auto TargetAS = getContext().getTargetAddressSpace(T.getAddressSpace()); 3181 auto PtrTy = ATPO.getElementType()->getPointerTo(TargetAS); 3182 auto ASC = getTargetHooks().performAddrSpaceCast( 3183 CGM, ATPO.getPointer(), AS, T.getAddressSpace(), PtrTy); 3184 ATPO = ConstantAddress(ASC, ATPO.getElementType(), ATPO.getAlignment()); 3185 } 3186 3187 return MakeAddrLValue(ATPO, T, AlignmentSource::Decl); 3188 } 3189 3190 llvm_unreachable("Unhandled DeclRefExpr"); 3191 } 3192 3193 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) { 3194 // __extension__ doesn't affect lvalue-ness. 3195 if (E->getOpcode() == UO_Extension) 3196 return EmitLValue(E->getSubExpr()); 3197 3198 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType()); 3199 switch (E->getOpcode()) { 3200 default: llvm_unreachable("Unknown unary operator lvalue!"); 3201 case UO_Deref: { 3202 QualType T = E->getSubExpr()->getType()->getPointeeType(); 3203 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type"); 3204 3205 LValueBaseInfo BaseInfo; 3206 TBAAAccessInfo TBAAInfo; 3207 Address Addr = EmitPointerWithAlignment(E->getSubExpr(), &BaseInfo, 3208 &TBAAInfo); 3209 LValue LV = MakeAddrLValue(Addr, T, BaseInfo, TBAAInfo); 3210 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace()); 3211 3212 // We should not generate __weak write barrier on indirect reference 3213 // of a pointer to object; as in void foo (__weak id *param); *param = 0; 3214 // But, we continue to generate __strong write barrier on indirect write 3215 // into a pointer to object. 3216 if (getLangOpts().ObjC && 3217 getLangOpts().getGC() != LangOptions::NonGC && 3218 LV.isObjCWeak()) 3219 LV.setNonGC(!E->isOBJCGCCandidate(getContext())); 3220 return LV; 3221 } 3222 case UO_Real: 3223 case UO_Imag: { 3224 LValue LV = EmitLValue(E->getSubExpr()); 3225 assert(LV.isSimple() && "real/imag on non-ordinary l-value"); 3226 3227 // __real is valid on scalars. This is a faster way of testing that. 3228 // __imag can only produce an rvalue on scalars. 3229 if (E->getOpcode() == UO_Real && 3230 !LV.getAddress().getElementType()->isStructTy()) { 3231 assert(E->getSubExpr()->getType()->isArithmeticType()); 3232 return LV; 3233 } 3234 3235 QualType T = ExprTy->castAs<ComplexType>()->getElementType(); 3236 3237 Address Component = 3238 (E->getOpcode() == UO_Real 3239 ? emitAddrOfRealComponent(LV.getAddress(), LV.getType()) 3240 : emitAddrOfImagComponent(LV.getAddress(), LV.getType())); 3241 LValue ElemLV = MakeAddrLValue(Component, T, LV.getBaseInfo(), 3242 CGM.getTBAAInfoForSubobject(LV, T)); 3243 ElemLV.getQuals().addQualifiers(LV.getQuals()); 3244 return ElemLV; 3245 } 3246 case UO_PreInc: 3247 case UO_PreDec: { 3248 LValue LV = EmitLValue(E->getSubExpr()); 3249 bool isInc = E->getOpcode() == UO_PreInc; 3250 3251 if (E->getType()->isAnyComplexType()) 3252 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/); 3253 else 3254 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/); 3255 return LV; 3256 } 3257 } 3258 } 3259 3260 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) { 3261 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E), 3262 E->getType(), AlignmentSource::Decl); 3263 } 3264 3265 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) { 3266 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E), 3267 E->getType(), AlignmentSource::Decl); 3268 } 3269 3270 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) { 3271 auto SL = E->getFunctionName(); 3272 assert(SL != nullptr && "No StringLiteral name in PredefinedExpr"); 3273 StringRef FnName = CurFn->getName(); 3274 if (FnName.starts_with("\01")) 3275 FnName = FnName.substr(1); 3276 StringRef NameItems[] = { 3277 PredefinedExpr::getIdentKindName(E->getIdentKind()), FnName}; 3278 std::string GVName = llvm::join(NameItems, NameItems + 2, "."); 3279 if (auto *BD = dyn_cast_or_null<BlockDecl>(CurCodeDecl)) { 3280 std::string Name = std::string(SL->getString()); 3281 if (!Name.empty()) { 3282 unsigned Discriminator = 3283 CGM.getCXXABI().getMangleContext().getBlockId(BD, true); 3284 if (Discriminator) 3285 Name += "_" + Twine(Discriminator + 1).str(); 3286 auto C = CGM.GetAddrOfConstantCString(Name, GVName.c_str()); 3287 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl); 3288 } else { 3289 auto C = 3290 CGM.GetAddrOfConstantCString(std::string(FnName), GVName.c_str()); 3291 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl); 3292 } 3293 } 3294 auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName); 3295 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl); 3296 } 3297 3298 /// Emit a type description suitable for use by a runtime sanitizer library. The 3299 /// format of a type descriptor is 3300 /// 3301 /// \code 3302 /// { i16 TypeKind, i16 TypeInfo } 3303 /// \endcode 3304 /// 3305 /// followed by an array of i8 containing the type name. TypeKind is 0 for an 3306 /// integer, 1 for a floating point value, and -1 for anything else. 3307 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) { 3308 // Only emit each type's descriptor once. 3309 if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T)) 3310 return C; 3311 3312 uint16_t TypeKind = -1; 3313 uint16_t TypeInfo = 0; 3314 3315 if (T->isIntegerType()) { 3316 TypeKind = 0; 3317 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) | 3318 (T->isSignedIntegerType() ? 1 : 0); 3319 } else if (T->isFloatingType()) { 3320 TypeKind = 1; 3321 TypeInfo = getContext().getTypeSize(T); 3322 } 3323 3324 // Format the type name as if for a diagnostic, including quotes and 3325 // optionally an 'aka'. 3326 SmallString<32> Buffer; 3327 CGM.getDiags().ConvertArgToString( 3328 DiagnosticsEngine::ak_qualtype, (intptr_t)T.getAsOpaquePtr(), StringRef(), 3329 StringRef(), std::nullopt, Buffer, std::nullopt); 3330 3331 llvm::Constant *Components[] = { 3332 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo), 3333 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer) 3334 }; 3335 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components); 3336 3337 auto *GV = new llvm::GlobalVariable( 3338 CGM.getModule(), Descriptor->getType(), 3339 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor); 3340 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3341 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(GV); 3342 3343 // Remember the descriptor for this type. 3344 CGM.setTypeDescriptorInMap(T, GV); 3345 3346 return GV; 3347 } 3348 3349 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) { 3350 llvm::Type *TargetTy = IntPtrTy; 3351 3352 if (V->getType() == TargetTy) 3353 return V; 3354 3355 // Floating-point types which fit into intptr_t are bitcast to integers 3356 // and then passed directly (after zero-extension, if necessary). 3357 if (V->getType()->isFloatingPointTy()) { 3358 unsigned Bits = V->getType()->getPrimitiveSizeInBits().getFixedValue(); 3359 if (Bits <= TargetTy->getIntegerBitWidth()) 3360 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(), 3361 Bits)); 3362 } 3363 3364 // Integers which fit in intptr_t are zero-extended and passed directly. 3365 if (V->getType()->isIntegerTy() && 3366 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth()) 3367 return Builder.CreateZExt(V, TargetTy); 3368 3369 // Pointers are passed directly, everything else is passed by address. 3370 if (!V->getType()->isPointerTy()) { 3371 RawAddress Ptr = CreateDefaultAlignTempAlloca(V->getType()); 3372 Builder.CreateStore(V, Ptr); 3373 V = Ptr.getPointer(); 3374 } 3375 return Builder.CreatePtrToInt(V, TargetTy); 3376 } 3377 3378 /// Emit a representation of a SourceLocation for passing to a handler 3379 /// in a sanitizer runtime library. The format for this data is: 3380 /// \code 3381 /// struct SourceLocation { 3382 /// const char *Filename; 3383 /// int32_t Line, Column; 3384 /// }; 3385 /// \endcode 3386 /// For an invalid SourceLocation, the Filename pointer is null. 3387 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) { 3388 llvm::Constant *Filename; 3389 int Line, Column; 3390 3391 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc); 3392 if (PLoc.isValid()) { 3393 StringRef FilenameString = PLoc.getFilename(); 3394 3395 int PathComponentsToStrip = 3396 CGM.getCodeGenOpts().EmitCheckPathComponentsToStrip; 3397 if (PathComponentsToStrip < 0) { 3398 assert(PathComponentsToStrip != INT_MIN); 3399 int PathComponentsToKeep = -PathComponentsToStrip; 3400 auto I = llvm::sys::path::rbegin(FilenameString); 3401 auto E = llvm::sys::path::rend(FilenameString); 3402 while (I != E && --PathComponentsToKeep) 3403 ++I; 3404 3405 FilenameString = FilenameString.substr(I - E); 3406 } else if (PathComponentsToStrip > 0) { 3407 auto I = llvm::sys::path::begin(FilenameString); 3408 auto E = llvm::sys::path::end(FilenameString); 3409 while (I != E && PathComponentsToStrip--) 3410 ++I; 3411 3412 if (I != E) 3413 FilenameString = 3414 FilenameString.substr(I - llvm::sys::path::begin(FilenameString)); 3415 else 3416 FilenameString = llvm::sys::path::filename(FilenameString); 3417 } 3418 3419 auto FilenameGV = 3420 CGM.GetAddrOfConstantCString(std::string(FilenameString), ".src"); 3421 CGM.getSanitizerMetadata()->disableSanitizerForGlobal( 3422 cast<llvm::GlobalVariable>( 3423 FilenameGV.getPointer()->stripPointerCasts())); 3424 Filename = FilenameGV.getPointer(); 3425 Line = PLoc.getLine(); 3426 Column = PLoc.getColumn(); 3427 } else { 3428 Filename = llvm::Constant::getNullValue(Int8PtrTy); 3429 Line = Column = 0; 3430 } 3431 3432 llvm::Constant *Data[] = {Filename, Builder.getInt32(Line), 3433 Builder.getInt32(Column)}; 3434 3435 return llvm::ConstantStruct::getAnon(Data); 3436 } 3437 3438 namespace { 3439 /// Specify under what conditions this check can be recovered 3440 enum class CheckRecoverableKind { 3441 /// Always terminate program execution if this check fails. 3442 Unrecoverable, 3443 /// Check supports recovering, runtime has both fatal (noreturn) and 3444 /// non-fatal handlers for this check. 3445 Recoverable, 3446 /// Runtime conditionally aborts, always need to support recovery. 3447 AlwaysRecoverable 3448 }; 3449 } 3450 3451 static CheckRecoverableKind getRecoverableKind(SanitizerMask Kind) { 3452 assert(Kind.countPopulation() == 1); 3453 if (Kind == SanitizerKind::Vptr) 3454 return CheckRecoverableKind::AlwaysRecoverable; 3455 else if (Kind == SanitizerKind::Return || Kind == SanitizerKind::Unreachable) 3456 return CheckRecoverableKind::Unrecoverable; 3457 else 3458 return CheckRecoverableKind::Recoverable; 3459 } 3460 3461 namespace { 3462 struct SanitizerHandlerInfo { 3463 char const *const Name; 3464 unsigned Version; 3465 }; 3466 } 3467 3468 const SanitizerHandlerInfo SanitizerHandlers[] = { 3469 #define SANITIZER_CHECK(Enum, Name, Version) {#Name, Version}, 3470 LIST_SANITIZER_CHECKS 3471 #undef SANITIZER_CHECK 3472 }; 3473 3474 static void emitCheckHandlerCall(CodeGenFunction &CGF, 3475 llvm::FunctionType *FnType, 3476 ArrayRef<llvm::Value *> FnArgs, 3477 SanitizerHandler CheckHandler, 3478 CheckRecoverableKind RecoverKind, bool IsFatal, 3479 llvm::BasicBlock *ContBB) { 3480 assert(IsFatal || RecoverKind != CheckRecoverableKind::Unrecoverable); 3481 std::optional<ApplyDebugLocation> DL; 3482 if (!CGF.Builder.getCurrentDebugLocation()) { 3483 // Ensure that the call has at least an artificial debug location. 3484 DL.emplace(CGF, SourceLocation()); 3485 } 3486 bool NeedsAbortSuffix = 3487 IsFatal && RecoverKind != CheckRecoverableKind::Unrecoverable; 3488 bool MinimalRuntime = CGF.CGM.getCodeGenOpts().SanitizeMinimalRuntime; 3489 const SanitizerHandlerInfo &CheckInfo = SanitizerHandlers[CheckHandler]; 3490 const StringRef CheckName = CheckInfo.Name; 3491 std::string FnName = "__ubsan_handle_" + CheckName.str(); 3492 if (CheckInfo.Version && !MinimalRuntime) 3493 FnName += "_v" + llvm::utostr(CheckInfo.Version); 3494 if (MinimalRuntime) 3495 FnName += "_minimal"; 3496 if (NeedsAbortSuffix) 3497 FnName += "_abort"; 3498 bool MayReturn = 3499 !IsFatal || RecoverKind == CheckRecoverableKind::AlwaysRecoverable; 3500 3501 llvm::AttrBuilder B(CGF.getLLVMContext()); 3502 if (!MayReturn) { 3503 B.addAttribute(llvm::Attribute::NoReturn) 3504 .addAttribute(llvm::Attribute::NoUnwind); 3505 } 3506 B.addUWTableAttr(llvm::UWTableKind::Default); 3507 3508 llvm::FunctionCallee Fn = CGF.CGM.CreateRuntimeFunction( 3509 FnType, FnName, 3510 llvm::AttributeList::get(CGF.getLLVMContext(), 3511 llvm::AttributeList::FunctionIndex, B), 3512 /*Local=*/true); 3513 llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs); 3514 if (!MayReturn) { 3515 HandlerCall->setDoesNotReturn(); 3516 CGF.Builder.CreateUnreachable(); 3517 } else { 3518 CGF.Builder.CreateBr(ContBB); 3519 } 3520 } 3521 3522 void CodeGenFunction::EmitCheck( 3523 ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked, 3524 SanitizerHandler CheckHandler, ArrayRef<llvm::Constant *> StaticArgs, 3525 ArrayRef<llvm::Value *> DynamicArgs) { 3526 assert(IsSanitizerScope); 3527 assert(Checked.size() > 0); 3528 assert(CheckHandler >= 0 && 3529 size_t(CheckHandler) < std::size(SanitizerHandlers)); 3530 const StringRef CheckName = SanitizerHandlers[CheckHandler].Name; 3531 3532 llvm::Value *FatalCond = nullptr; 3533 llvm::Value *RecoverableCond = nullptr; 3534 llvm::Value *TrapCond = nullptr; 3535 for (int i = 0, n = Checked.size(); i < n; ++i) { 3536 llvm::Value *Check = Checked[i].first; 3537 // -fsanitize-trap= overrides -fsanitize-recover=. 3538 llvm::Value *&Cond = 3539 CGM.getCodeGenOpts().SanitizeTrap.has(Checked[i].second) 3540 ? TrapCond 3541 : CGM.getCodeGenOpts().SanitizeRecover.has(Checked[i].second) 3542 ? RecoverableCond 3543 : FatalCond; 3544 Cond = Cond ? Builder.CreateAnd(Cond, Check) : Check; 3545 } 3546 3547 if (ClSanitizeGuardChecks) { 3548 llvm::Value *Allow = 3549 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::allow_ubsan_check), 3550 llvm::ConstantInt::get(CGM.Int8Ty, CheckHandler)); 3551 3552 for (llvm::Value **Cond : {&FatalCond, &RecoverableCond, &TrapCond}) { 3553 if (*Cond) 3554 *Cond = Builder.CreateOr(*Cond, Builder.CreateNot(Allow)); 3555 } 3556 } 3557 3558 if (TrapCond) 3559 EmitTrapCheck(TrapCond, CheckHandler); 3560 if (!FatalCond && !RecoverableCond) 3561 return; 3562 3563 llvm::Value *JointCond; 3564 if (FatalCond && RecoverableCond) 3565 JointCond = Builder.CreateAnd(FatalCond, RecoverableCond); 3566 else 3567 JointCond = FatalCond ? FatalCond : RecoverableCond; 3568 assert(JointCond); 3569 3570 CheckRecoverableKind RecoverKind = getRecoverableKind(Checked[0].second); 3571 assert(SanOpts.has(Checked[0].second)); 3572 #ifndef NDEBUG 3573 for (int i = 1, n = Checked.size(); i < n; ++i) { 3574 assert(RecoverKind == getRecoverableKind(Checked[i].second) && 3575 "All recoverable kinds in a single check must be same!"); 3576 assert(SanOpts.has(Checked[i].second)); 3577 } 3578 #endif 3579 3580 llvm::BasicBlock *Cont = createBasicBlock("cont"); 3581 llvm::BasicBlock *Handlers = createBasicBlock("handler." + CheckName); 3582 llvm::Instruction *Branch = Builder.CreateCondBr(JointCond, Cont, Handlers); 3583 // Give hint that we very much don't expect to execute the handler 3584 llvm::MDBuilder MDHelper(getLLVMContext()); 3585 llvm::MDNode *Node = MDHelper.createLikelyBranchWeights(); 3586 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node); 3587 EmitBlock(Handlers); 3588 3589 // Handler functions take an i8* pointing to the (handler-specific) static 3590 // information block, followed by a sequence of intptr_t arguments 3591 // representing operand values. 3592 SmallVector<llvm::Value *, 4> Args; 3593 SmallVector<llvm::Type *, 4> ArgTypes; 3594 if (!CGM.getCodeGenOpts().SanitizeMinimalRuntime) { 3595 Args.reserve(DynamicArgs.size() + 1); 3596 ArgTypes.reserve(DynamicArgs.size() + 1); 3597 3598 // Emit handler arguments and create handler function type. 3599 if (!StaticArgs.empty()) { 3600 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs); 3601 auto *InfoPtr = new llvm::GlobalVariable( 3602 CGM.getModule(), Info->getType(), false, 3603 llvm::GlobalVariable::PrivateLinkage, Info, "", nullptr, 3604 llvm::GlobalVariable::NotThreadLocal, 3605 CGM.getDataLayout().getDefaultGlobalsAddressSpace()); 3606 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3607 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr); 3608 Args.push_back(InfoPtr); 3609 ArgTypes.push_back(Args.back()->getType()); 3610 } 3611 3612 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) { 3613 Args.push_back(EmitCheckValue(DynamicArgs[i])); 3614 ArgTypes.push_back(IntPtrTy); 3615 } 3616 } 3617 3618 llvm::FunctionType *FnType = 3619 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false); 3620 3621 if (!FatalCond || !RecoverableCond) { 3622 // Simple case: we need to generate a single handler call, either 3623 // fatal, or non-fatal. 3624 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, 3625 (FatalCond != nullptr), Cont); 3626 } else { 3627 // Emit two handler calls: first one for set of unrecoverable checks, 3628 // another one for recoverable. 3629 llvm::BasicBlock *NonFatalHandlerBB = 3630 createBasicBlock("non_fatal." + CheckName); 3631 llvm::BasicBlock *FatalHandlerBB = createBasicBlock("fatal." + CheckName); 3632 Builder.CreateCondBr(FatalCond, NonFatalHandlerBB, FatalHandlerBB); 3633 EmitBlock(FatalHandlerBB); 3634 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, true, 3635 NonFatalHandlerBB); 3636 EmitBlock(NonFatalHandlerBB); 3637 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, false, 3638 Cont); 3639 } 3640 3641 EmitBlock(Cont); 3642 } 3643 3644 void CodeGenFunction::EmitCfiSlowPathCheck( 3645 SanitizerMask Kind, llvm::Value *Cond, llvm::ConstantInt *TypeId, 3646 llvm::Value *Ptr, ArrayRef<llvm::Constant *> StaticArgs) { 3647 llvm::BasicBlock *Cont = createBasicBlock("cfi.cont"); 3648 3649 llvm::BasicBlock *CheckBB = createBasicBlock("cfi.slowpath"); 3650 llvm::BranchInst *BI = Builder.CreateCondBr(Cond, Cont, CheckBB); 3651 3652 llvm::MDBuilder MDHelper(getLLVMContext()); 3653 llvm::MDNode *Node = MDHelper.createLikelyBranchWeights(); 3654 BI->setMetadata(llvm::LLVMContext::MD_prof, Node); 3655 3656 EmitBlock(CheckBB); 3657 3658 bool WithDiag = !CGM.getCodeGenOpts().SanitizeTrap.has(Kind); 3659 3660 llvm::CallInst *CheckCall; 3661 llvm::FunctionCallee SlowPathFn; 3662 if (WithDiag) { 3663 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs); 3664 auto *InfoPtr = 3665 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false, 3666 llvm::GlobalVariable::PrivateLinkage, Info); 3667 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3668 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr); 3669 3670 SlowPathFn = CGM.getModule().getOrInsertFunction( 3671 "__cfi_slowpath_diag", 3672 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, 3673 false)); 3674 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr, InfoPtr}); 3675 } else { 3676 SlowPathFn = CGM.getModule().getOrInsertFunction( 3677 "__cfi_slowpath", 3678 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy}, false)); 3679 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr}); 3680 } 3681 3682 CGM.setDSOLocal( 3683 cast<llvm::GlobalValue>(SlowPathFn.getCallee()->stripPointerCasts())); 3684 CheckCall->setDoesNotThrow(); 3685 3686 EmitBlock(Cont); 3687 } 3688 3689 // Emit a stub for __cfi_check function so that the linker knows about this 3690 // symbol in LTO mode. 3691 void CodeGenFunction::EmitCfiCheckStub() { 3692 llvm::Module *M = &CGM.getModule(); 3693 ASTContext &C = getContext(); 3694 QualType QInt64Ty = C.getIntTypeForBitwidth(64, false); 3695 3696 FunctionArgList FnArgs; 3697 ImplicitParamDecl ArgCallsiteTypeId(C, QInt64Ty, ImplicitParamKind::Other); 3698 ImplicitParamDecl ArgAddr(C, C.VoidPtrTy, ImplicitParamKind::Other); 3699 ImplicitParamDecl ArgCFICheckFailData(C, C.VoidPtrTy, 3700 ImplicitParamKind::Other); 3701 FnArgs.push_back(&ArgCallsiteTypeId); 3702 FnArgs.push_back(&ArgAddr); 3703 FnArgs.push_back(&ArgCFICheckFailData); 3704 const CGFunctionInfo &FI = 3705 CGM.getTypes().arrangeBuiltinFunctionDeclaration(C.VoidTy, FnArgs); 3706 3707 llvm::Function *F = llvm::Function::Create( 3708 llvm::FunctionType::get(VoidTy, {Int64Ty, VoidPtrTy, VoidPtrTy}, false), 3709 llvm::GlobalValue::WeakAnyLinkage, "__cfi_check", M); 3710 CGM.SetLLVMFunctionAttributes(GlobalDecl(), FI, F, /*IsThunk=*/false); 3711 CGM.SetLLVMFunctionAttributesForDefinition(nullptr, F); 3712 F->setAlignment(llvm::Align(4096)); 3713 CGM.setDSOLocal(F); 3714 3715 llvm::LLVMContext &Ctx = M->getContext(); 3716 llvm::BasicBlock *BB = llvm::BasicBlock::Create(Ctx, "entry", F); 3717 // CrossDSOCFI pass is not executed if there is no executable code. 3718 SmallVector<llvm::Value*> Args{F->getArg(2), F->getArg(1)}; 3719 llvm::CallInst::Create(M->getFunction("__cfi_check_fail"), Args, "", BB); 3720 llvm::ReturnInst::Create(Ctx, nullptr, BB); 3721 } 3722 3723 // This function is basically a switch over the CFI failure kind, which is 3724 // extracted from CFICheckFailData (1st function argument). Each case is either 3725 // llvm.trap or a call to one of the two runtime handlers, based on 3726 // -fsanitize-trap and -fsanitize-recover settings. Default case (invalid 3727 // failure kind) traps, but this should really never happen. CFICheckFailData 3728 // can be nullptr if the calling module has -fsanitize-trap behavior for this 3729 // check kind; in this case __cfi_check_fail traps as well. 3730 void CodeGenFunction::EmitCfiCheckFail() { 3731 SanitizerScope SanScope(this); 3732 FunctionArgList Args; 3733 ImplicitParamDecl ArgData(getContext(), getContext().VoidPtrTy, 3734 ImplicitParamKind::Other); 3735 ImplicitParamDecl ArgAddr(getContext(), getContext().VoidPtrTy, 3736 ImplicitParamKind::Other); 3737 Args.push_back(&ArgData); 3738 Args.push_back(&ArgAddr); 3739 3740 const CGFunctionInfo &FI = 3741 CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, Args); 3742 3743 llvm::Function *F = llvm::Function::Create( 3744 llvm::FunctionType::get(VoidTy, {VoidPtrTy, VoidPtrTy}, false), 3745 llvm::GlobalValue::WeakODRLinkage, "__cfi_check_fail", &CGM.getModule()); 3746 3747 CGM.SetLLVMFunctionAttributes(GlobalDecl(), FI, F, /*IsThunk=*/false); 3748 CGM.SetLLVMFunctionAttributesForDefinition(nullptr, F); 3749 F->setVisibility(llvm::GlobalValue::HiddenVisibility); 3750 3751 StartFunction(GlobalDecl(), CGM.getContext().VoidTy, F, FI, Args, 3752 SourceLocation()); 3753 3754 // This function is not affected by NoSanitizeList. This function does 3755 // not have a source location, but "src:*" would still apply. Revert any 3756 // changes to SanOpts made in StartFunction. 3757 SanOpts = CGM.getLangOpts().Sanitize; 3758 3759 llvm::Value *Data = 3760 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgData), /*Volatile=*/false, 3761 CGM.getContext().VoidPtrTy, ArgData.getLocation()); 3762 llvm::Value *Addr = 3763 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgAddr), /*Volatile=*/false, 3764 CGM.getContext().VoidPtrTy, ArgAddr.getLocation()); 3765 3766 // Data == nullptr means the calling module has trap behaviour for this check. 3767 llvm::Value *DataIsNotNullPtr = 3768 Builder.CreateICmpNE(Data, llvm::ConstantPointerNull::get(Int8PtrTy)); 3769 EmitTrapCheck(DataIsNotNullPtr, SanitizerHandler::CFICheckFail); 3770 3771 llvm::StructType *SourceLocationTy = 3772 llvm::StructType::get(VoidPtrTy, Int32Ty, Int32Ty); 3773 llvm::StructType *CfiCheckFailDataTy = 3774 llvm::StructType::get(Int8Ty, SourceLocationTy, VoidPtrTy); 3775 3776 llvm::Value *V = Builder.CreateConstGEP2_32( 3777 CfiCheckFailDataTy, 3778 Builder.CreatePointerCast(Data, CfiCheckFailDataTy->getPointerTo(0)), 0, 3779 0); 3780 3781 Address CheckKindAddr(V, Int8Ty, getIntAlign()); 3782 llvm::Value *CheckKind = Builder.CreateLoad(CheckKindAddr); 3783 3784 llvm::Value *AllVtables = llvm::MetadataAsValue::get( 3785 CGM.getLLVMContext(), 3786 llvm::MDString::get(CGM.getLLVMContext(), "all-vtables")); 3787 llvm::Value *ValidVtable = Builder.CreateZExt( 3788 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::type_test), 3789 {Addr, AllVtables}), 3790 IntPtrTy); 3791 3792 const std::pair<int, SanitizerMask> CheckKinds[] = { 3793 {CFITCK_VCall, SanitizerKind::CFIVCall}, 3794 {CFITCK_NVCall, SanitizerKind::CFINVCall}, 3795 {CFITCK_DerivedCast, SanitizerKind::CFIDerivedCast}, 3796 {CFITCK_UnrelatedCast, SanitizerKind::CFIUnrelatedCast}, 3797 {CFITCK_ICall, SanitizerKind::CFIICall}}; 3798 3799 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 5> Checks; 3800 for (auto CheckKindMaskPair : CheckKinds) { 3801 int Kind = CheckKindMaskPair.first; 3802 SanitizerMask Mask = CheckKindMaskPair.second; 3803 llvm::Value *Cond = 3804 Builder.CreateICmpNE(CheckKind, llvm::ConstantInt::get(Int8Ty, Kind)); 3805 if (CGM.getLangOpts().Sanitize.has(Mask)) 3806 EmitCheck(std::make_pair(Cond, Mask), SanitizerHandler::CFICheckFail, {}, 3807 {Data, Addr, ValidVtable}); 3808 else 3809 EmitTrapCheck(Cond, SanitizerHandler::CFICheckFail); 3810 } 3811 3812 FinishFunction(); 3813 // The only reference to this function will be created during LTO link. 3814 // Make sure it survives until then. 3815 CGM.addUsedGlobal(F); 3816 } 3817 3818 void CodeGenFunction::EmitUnreachable(SourceLocation Loc) { 3819 if (SanOpts.has(SanitizerKind::Unreachable)) { 3820 SanitizerScope SanScope(this); 3821 EmitCheck(std::make_pair(static_cast<llvm::Value *>(Builder.getFalse()), 3822 SanitizerKind::Unreachable), 3823 SanitizerHandler::BuiltinUnreachable, 3824 EmitCheckSourceLocation(Loc), std::nullopt); 3825 } 3826 Builder.CreateUnreachable(); 3827 } 3828 3829 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked, 3830 SanitizerHandler CheckHandlerID) { 3831 llvm::BasicBlock *Cont = createBasicBlock("cont"); 3832 3833 // If we're optimizing, collapse all calls to trap down to just one per 3834 // check-type per function to save on code size. 3835 if ((int)TrapBBs.size() <= CheckHandlerID) 3836 TrapBBs.resize(CheckHandlerID + 1); 3837 3838 llvm::BasicBlock *&TrapBB = TrapBBs[CheckHandlerID]; 3839 3840 if (!ClSanitizeDebugDeoptimization && 3841 CGM.getCodeGenOpts().OptimizationLevel && TrapBB && 3842 (!CurCodeDecl || !CurCodeDecl->hasAttr<OptimizeNoneAttr>())) { 3843 auto Call = TrapBB->begin(); 3844 assert(isa<llvm::CallInst>(Call) && "Expected call in trap BB"); 3845 3846 Call->applyMergedLocation(Call->getDebugLoc(), 3847 Builder.getCurrentDebugLocation()); 3848 Builder.CreateCondBr(Checked, Cont, TrapBB); 3849 } else { 3850 TrapBB = createBasicBlock("trap"); 3851 Builder.CreateCondBr(Checked, Cont, TrapBB); 3852 EmitBlock(TrapBB); 3853 3854 llvm::CallInst *TrapCall = Builder.CreateCall( 3855 CGM.getIntrinsic(llvm::Intrinsic::ubsantrap), 3856 llvm::ConstantInt::get(CGM.Int8Ty, 3857 ClSanitizeDebugDeoptimization 3858 ? TrapBB->getParent()->size() 3859 : static_cast<uint64_t>(CheckHandlerID))); 3860 3861 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) { 3862 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name", 3863 CGM.getCodeGenOpts().TrapFuncName); 3864 TrapCall->addFnAttr(A); 3865 } 3866 TrapCall->setDoesNotReturn(); 3867 TrapCall->setDoesNotThrow(); 3868 Builder.CreateUnreachable(); 3869 } 3870 3871 EmitBlock(Cont); 3872 } 3873 3874 llvm::CallInst *CodeGenFunction::EmitTrapCall(llvm::Intrinsic::ID IntrID) { 3875 llvm::CallInst *TrapCall = 3876 Builder.CreateCall(CGM.getIntrinsic(IntrID)); 3877 3878 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) { 3879 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name", 3880 CGM.getCodeGenOpts().TrapFuncName); 3881 TrapCall->addFnAttr(A); 3882 } 3883 3884 return TrapCall; 3885 } 3886 3887 Address CodeGenFunction::EmitArrayToPointerDecay(const Expr *E, 3888 LValueBaseInfo *BaseInfo, 3889 TBAAAccessInfo *TBAAInfo) { 3890 assert(E->getType()->isArrayType() && 3891 "Array to pointer decay must have array source type!"); 3892 3893 // Expressions of array type can't be bitfields or vector elements. 3894 LValue LV = EmitLValue(E); 3895 Address Addr = LV.getAddress(); 3896 3897 // If the array type was an incomplete type, we need to make sure 3898 // the decay ends up being the right type. 3899 llvm::Type *NewTy = ConvertType(E->getType()); 3900 Addr = Addr.withElementType(NewTy); 3901 3902 // Note that VLA pointers are always decayed, so we don't need to do 3903 // anything here. 3904 if (!E->getType()->isVariableArrayType()) { 3905 assert(isa<llvm::ArrayType>(Addr.getElementType()) && 3906 "Expected pointer to array"); 3907 Addr = Builder.CreateConstArrayGEP(Addr, 0, "arraydecay"); 3908 } 3909 3910 // The result of this decay conversion points to an array element within the 3911 // base lvalue. However, since TBAA currently does not support representing 3912 // accesses to elements of member arrays, we conservatively represent accesses 3913 // to the pointee object as if it had no any base lvalue specified. 3914 // TODO: Support TBAA for member arrays. 3915 QualType EltType = E->getType()->castAsArrayTypeUnsafe()->getElementType(); 3916 if (BaseInfo) *BaseInfo = LV.getBaseInfo(); 3917 if (TBAAInfo) *TBAAInfo = CGM.getTBAAAccessInfo(EltType); 3918 3919 return Addr.withElementType(ConvertTypeForMem(EltType)); 3920 } 3921 3922 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an 3923 /// array to pointer, return the array subexpression. 3924 static const Expr *isSimpleArrayDecayOperand(const Expr *E) { 3925 // If this isn't just an array->pointer decay, bail out. 3926 const auto *CE = dyn_cast<CastExpr>(E); 3927 if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay) 3928 return nullptr; 3929 3930 // If this is a decay from variable width array, bail out. 3931 const Expr *SubExpr = CE->getSubExpr(); 3932 if (SubExpr->getType()->isVariableArrayType()) 3933 return nullptr; 3934 3935 return SubExpr; 3936 } 3937 3938 static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF, 3939 llvm::Type *elemType, 3940 llvm::Value *ptr, 3941 ArrayRef<llvm::Value*> indices, 3942 bool inbounds, 3943 bool signedIndices, 3944 SourceLocation loc, 3945 const llvm::Twine &name = "arrayidx") { 3946 if (inbounds) { 3947 return CGF.EmitCheckedInBoundsGEP(elemType, ptr, indices, signedIndices, 3948 CodeGenFunction::NotSubtraction, loc, 3949 name); 3950 } else { 3951 return CGF.Builder.CreateGEP(elemType, ptr, indices, name); 3952 } 3953 } 3954 3955 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr, 3956 ArrayRef<llvm::Value *> indices, 3957 llvm::Type *elementType, bool inbounds, 3958 bool signedIndices, SourceLocation loc, 3959 CharUnits align, 3960 const llvm::Twine &name = "arrayidx") { 3961 if (inbounds) { 3962 return CGF.EmitCheckedInBoundsGEP(addr, indices, elementType, signedIndices, 3963 CodeGenFunction::NotSubtraction, loc, 3964 align, name); 3965 } else { 3966 return CGF.Builder.CreateGEP(addr, indices, elementType, align, name); 3967 } 3968 } 3969 3970 static CharUnits getArrayElementAlign(CharUnits arrayAlign, 3971 llvm::Value *idx, 3972 CharUnits eltSize) { 3973 // If we have a constant index, we can use the exact offset of the 3974 // element we're accessing. 3975 if (auto constantIdx = dyn_cast<llvm::ConstantInt>(idx)) { 3976 CharUnits offset = constantIdx->getZExtValue() * eltSize; 3977 return arrayAlign.alignmentAtOffset(offset); 3978 3979 // Otherwise, use the worst-case alignment for any element. 3980 } else { 3981 return arrayAlign.alignmentOfArrayElement(eltSize); 3982 } 3983 } 3984 3985 static QualType getFixedSizeElementType(const ASTContext &ctx, 3986 const VariableArrayType *vla) { 3987 QualType eltType; 3988 do { 3989 eltType = vla->getElementType(); 3990 } while ((vla = ctx.getAsVariableArrayType(eltType))); 3991 return eltType; 3992 } 3993 3994 static bool hasBPFPreserveStaticOffset(const RecordDecl *D) { 3995 return D && D->hasAttr<BPFPreserveStaticOffsetAttr>(); 3996 } 3997 3998 static bool hasBPFPreserveStaticOffset(const Expr *E) { 3999 if (!E) 4000 return false; 4001 QualType PointeeType = E->getType()->getPointeeType(); 4002 if (PointeeType.isNull()) 4003 return false; 4004 if (const auto *BaseDecl = PointeeType->getAsRecordDecl()) 4005 return hasBPFPreserveStaticOffset(BaseDecl); 4006 return false; 4007 } 4008 4009 // Wraps Addr with a call to llvm.preserve.static.offset intrinsic. 4010 static Address wrapWithBPFPreserveStaticOffset(CodeGenFunction &CGF, 4011 Address &Addr) { 4012 if (!CGF.getTarget().getTriple().isBPF()) 4013 return Addr; 4014 4015 llvm::Function *Fn = 4016 CGF.CGM.getIntrinsic(llvm::Intrinsic::preserve_static_offset); 4017 llvm::CallInst *Call = CGF.Builder.CreateCall(Fn, {Addr.emitRawPointer(CGF)}); 4018 return Address(Call, Addr.getElementType(), Addr.getAlignment()); 4019 } 4020 4021 /// Given an array base, check whether its member access belongs to a record 4022 /// with preserve_access_index attribute or not. 4023 static bool IsPreserveAIArrayBase(CodeGenFunction &CGF, const Expr *ArrayBase) { 4024 if (!ArrayBase || !CGF.getDebugInfo()) 4025 return false; 4026 4027 // Only support base as either a MemberExpr or DeclRefExpr. 4028 // DeclRefExpr to cover cases like: 4029 // struct s { int a; int b[10]; }; 4030 // struct s *p; 4031 // p[1].a 4032 // p[1] will generate a DeclRefExpr and p[1].a is a MemberExpr. 4033 // p->b[5] is a MemberExpr example. 4034 const Expr *E = ArrayBase->IgnoreImpCasts(); 4035 if (const auto *ME = dyn_cast<MemberExpr>(E)) 4036 return ME->getMemberDecl()->hasAttr<BPFPreserveAccessIndexAttr>(); 4037 4038 if (const auto *DRE = dyn_cast<DeclRefExpr>(E)) { 4039 const auto *VarDef = dyn_cast<VarDecl>(DRE->getDecl()); 4040 if (!VarDef) 4041 return false; 4042 4043 const auto *PtrT = VarDef->getType()->getAs<PointerType>(); 4044 if (!PtrT) 4045 return false; 4046 4047 const auto *PointeeT = PtrT->getPointeeType() 4048 ->getUnqualifiedDesugaredType(); 4049 if (const auto *RecT = dyn_cast<RecordType>(PointeeT)) 4050 return RecT->getDecl()->hasAttr<BPFPreserveAccessIndexAttr>(); 4051 return false; 4052 } 4053 4054 return false; 4055 } 4056 4057 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr, 4058 ArrayRef<llvm::Value *> indices, 4059 QualType eltType, bool inbounds, 4060 bool signedIndices, SourceLocation loc, 4061 QualType *arrayType = nullptr, 4062 const Expr *Base = nullptr, 4063 const llvm::Twine &name = "arrayidx") { 4064 // All the indices except that last must be zero. 4065 #ifndef NDEBUG 4066 for (auto *idx : indices.drop_back()) 4067 assert(isa<llvm::ConstantInt>(idx) && 4068 cast<llvm::ConstantInt>(idx)->isZero()); 4069 #endif 4070 4071 // Determine the element size of the statically-sized base. This is 4072 // the thing that the indices are expressed in terms of. 4073 if (auto vla = CGF.getContext().getAsVariableArrayType(eltType)) { 4074 eltType = getFixedSizeElementType(CGF.getContext(), vla); 4075 } 4076 4077 // We can use that to compute the best alignment of the element. 4078 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType); 4079 CharUnits eltAlign = 4080 getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize); 4081 4082 if (hasBPFPreserveStaticOffset(Base)) 4083 addr = wrapWithBPFPreserveStaticOffset(CGF, addr); 4084 4085 llvm::Value *eltPtr; 4086 auto LastIndex = dyn_cast<llvm::ConstantInt>(indices.back()); 4087 if (!LastIndex || 4088 (!CGF.IsInPreservedAIRegion && !IsPreserveAIArrayBase(CGF, Base))) { 4089 addr = emitArraySubscriptGEP(CGF, addr, indices, 4090 CGF.ConvertTypeForMem(eltType), inbounds, 4091 signedIndices, loc, eltAlign, name); 4092 return addr; 4093 } else { 4094 // Remember the original array subscript for bpf target 4095 unsigned idx = LastIndex->getZExtValue(); 4096 llvm::DIType *DbgInfo = nullptr; 4097 if (arrayType) 4098 DbgInfo = CGF.getDebugInfo()->getOrCreateStandaloneType(*arrayType, loc); 4099 eltPtr = CGF.Builder.CreatePreserveArrayAccessIndex( 4100 addr.getElementType(), addr.emitRawPointer(CGF), indices.size() - 1, 4101 idx, DbgInfo); 4102 } 4103 4104 return Address(eltPtr, CGF.ConvertTypeForMem(eltType), eltAlign); 4105 } 4106 4107 /// The offset of a field from the beginning of the record. 4108 static bool getFieldOffsetInBits(CodeGenFunction &CGF, const RecordDecl *RD, 4109 const FieldDecl *FD, int64_t &Offset) { 4110 ASTContext &Ctx = CGF.getContext(); 4111 const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(RD); 4112 unsigned FieldNo = 0; 4113 4114 for (const Decl *D : RD->decls()) { 4115 if (const auto *Record = dyn_cast<RecordDecl>(D)) 4116 if (getFieldOffsetInBits(CGF, Record, FD, Offset)) { 4117 Offset += Layout.getFieldOffset(FieldNo); 4118 return true; 4119 } 4120 4121 if (const auto *Field = dyn_cast<FieldDecl>(D)) 4122 if (FD == Field) { 4123 Offset += Layout.getFieldOffset(FieldNo); 4124 return true; 4125 } 4126 4127 if (isa<FieldDecl>(D)) 4128 ++FieldNo; 4129 } 4130 4131 return false; 4132 } 4133 4134 /// Returns the relative offset difference between \p FD1 and \p FD2. 4135 /// \code 4136 /// offsetof(struct foo, FD1) - offsetof(struct foo, FD2) 4137 /// \endcode 4138 /// Both fields must be within the same struct. 4139 static std::optional<int64_t> getOffsetDifferenceInBits(CodeGenFunction &CGF, 4140 const FieldDecl *FD1, 4141 const FieldDecl *FD2) { 4142 const RecordDecl *FD1OuterRec = 4143 FD1->getParent()->getOuterLexicalRecordContext(); 4144 const RecordDecl *FD2OuterRec = 4145 FD2->getParent()->getOuterLexicalRecordContext(); 4146 4147 if (FD1OuterRec != FD2OuterRec) 4148 // Fields must be within the same RecordDecl. 4149 return std::optional<int64_t>(); 4150 4151 int64_t FD1Offset = 0; 4152 if (!getFieldOffsetInBits(CGF, FD1OuterRec, FD1, FD1Offset)) 4153 return std::optional<int64_t>(); 4154 4155 int64_t FD2Offset = 0; 4156 if (!getFieldOffsetInBits(CGF, FD2OuterRec, FD2, FD2Offset)) 4157 return std::optional<int64_t>(); 4158 4159 return std::make_optional<int64_t>(FD1Offset - FD2Offset); 4160 } 4161 4162 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E, 4163 bool Accessed) { 4164 // The index must always be an integer, which is not an aggregate. Emit it 4165 // in lexical order (this complexity is, sadly, required by C++17). 4166 llvm::Value *IdxPre = 4167 (E->getLHS() == E->getIdx()) ? EmitScalarExpr(E->getIdx()) : nullptr; 4168 bool SignedIndices = false; 4169 auto EmitIdxAfterBase = [&, IdxPre](bool Promote) -> llvm::Value * { 4170 auto *Idx = IdxPre; 4171 if (E->getLHS() != E->getIdx()) { 4172 assert(E->getRHS() == E->getIdx() && "index was neither LHS nor RHS"); 4173 Idx = EmitScalarExpr(E->getIdx()); 4174 } 4175 4176 QualType IdxTy = E->getIdx()->getType(); 4177 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType(); 4178 SignedIndices |= IdxSigned; 4179 4180 if (SanOpts.has(SanitizerKind::ArrayBounds)) 4181 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed); 4182 4183 // Extend or truncate the index type to 32 or 64-bits. 4184 if (Promote && Idx->getType() != IntPtrTy) 4185 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom"); 4186 4187 return Idx; 4188 }; 4189 IdxPre = nullptr; 4190 4191 // If the base is a vector type, then we are forming a vector element lvalue 4192 // with this subscript. 4193 if (E->getBase()->getType()->isSubscriptableVectorType() && 4194 !isa<ExtVectorElementExpr>(E->getBase())) { 4195 // Emit the vector as an lvalue to get its address. 4196 LValue LHS = EmitLValue(E->getBase()); 4197 auto *Idx = EmitIdxAfterBase(/*Promote*/false); 4198 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!"); 4199 return LValue::MakeVectorElt(LHS.getAddress(), Idx, E->getBase()->getType(), 4200 LHS.getBaseInfo(), TBAAAccessInfo()); 4201 } 4202 4203 // All the other cases basically behave like simple offsetting. 4204 4205 // Handle the extvector case we ignored above. 4206 if (isa<ExtVectorElementExpr>(E->getBase())) { 4207 LValue LV = EmitLValue(E->getBase()); 4208 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 4209 Address Addr = EmitExtVectorElementLValue(LV); 4210 4211 QualType EltType = LV.getType()->castAs<VectorType>()->getElementType(); 4212 Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true, 4213 SignedIndices, E->getExprLoc()); 4214 return MakeAddrLValue(Addr, EltType, LV.getBaseInfo(), 4215 CGM.getTBAAInfoForSubobject(LV, EltType)); 4216 } 4217 4218 LValueBaseInfo EltBaseInfo; 4219 TBAAAccessInfo EltTBAAInfo; 4220 Address Addr = Address::invalid(); 4221 if (const VariableArrayType *vla = 4222 getContext().getAsVariableArrayType(E->getType())) { 4223 // The base must be a pointer, which is not an aggregate. Emit 4224 // it. It needs to be emitted first in case it's what captures 4225 // the VLA bounds. 4226 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo); 4227 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 4228 4229 // The element count here is the total number of non-VLA elements. 4230 llvm::Value *numElements = getVLASize(vla).NumElts; 4231 4232 // Effectively, the multiply by the VLA size is part of the GEP. 4233 // GEP indexes are signed, and scaling an index isn't permitted to 4234 // signed-overflow, so we use the same semantics for our explicit 4235 // multiply. We suppress this if overflow is not undefined behavior. 4236 if (getLangOpts().isSignedOverflowDefined()) { 4237 Idx = Builder.CreateMul(Idx, numElements); 4238 } else { 4239 Idx = Builder.CreateNSWMul(Idx, numElements); 4240 } 4241 4242 Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(), 4243 !getLangOpts().isSignedOverflowDefined(), 4244 SignedIndices, E->getExprLoc()); 4245 4246 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){ 4247 // Indexing over an interface, as in "NSString *P; P[4];" 4248 4249 // Emit the base pointer. 4250 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo); 4251 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 4252 4253 CharUnits InterfaceSize = getContext().getTypeSizeInChars(OIT); 4254 llvm::Value *InterfaceSizeVal = 4255 llvm::ConstantInt::get(Idx->getType(), InterfaceSize.getQuantity()); 4256 4257 llvm::Value *ScaledIdx = Builder.CreateMul(Idx, InterfaceSizeVal); 4258 4259 // We don't necessarily build correct LLVM struct types for ObjC 4260 // interfaces, so we can't rely on GEP to do this scaling 4261 // correctly, so we need to cast to i8*. FIXME: is this actually 4262 // true? A lot of other things in the fragile ABI would break... 4263 llvm::Type *OrigBaseElemTy = Addr.getElementType(); 4264 4265 // Do the GEP. 4266 CharUnits EltAlign = 4267 getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize); 4268 llvm::Value *EltPtr = 4269 emitArraySubscriptGEP(*this, Int8Ty, Addr.emitRawPointer(*this), 4270 ScaledIdx, false, SignedIndices, E->getExprLoc()); 4271 Addr = Address(EltPtr, OrigBaseElemTy, EltAlign); 4272 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) { 4273 // If this is A[i] where A is an array, the frontend will have decayed the 4274 // base to be a ArrayToPointerDecay implicit cast. While correct, it is 4275 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a 4276 // "gep x, i" here. Emit one "gep A, 0, i". 4277 assert(Array->getType()->isArrayType() && 4278 "Array to pointer decay must have array source type!"); 4279 LValue ArrayLV; 4280 // For simple multidimensional array indexing, set the 'accessed' flag for 4281 // better bounds-checking of the base expression. 4282 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array)) 4283 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true); 4284 else 4285 ArrayLV = EmitLValue(Array); 4286 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 4287 4288 if (SanOpts.has(SanitizerKind::ArrayBounds)) { 4289 // If the array being accessed has a "counted_by" attribute, generate 4290 // bounds checking code. The "count" field is at the top level of the 4291 // struct or in an anonymous struct, that's also at the top level. Future 4292 // expansions may allow the "count" to reside at any place in the struct, 4293 // but the value of "counted_by" will be a "simple" path to the count, 4294 // i.e. "a.b.count", so we shouldn't need the full force of EmitLValue or 4295 // similar to emit the correct GEP. 4296 const LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel = 4297 getLangOpts().getStrictFlexArraysLevel(); 4298 4299 if (const auto *ME = dyn_cast<MemberExpr>(Array); 4300 ME && 4301 ME->isFlexibleArrayMemberLike(getContext(), StrictFlexArraysLevel) && 4302 ME->getMemberDecl()->getType()->isCountAttributedType()) { 4303 const FieldDecl *FAMDecl = dyn_cast<FieldDecl>(ME->getMemberDecl()); 4304 if (const FieldDecl *CountFD = FindCountedByField(FAMDecl)) { 4305 if (std::optional<int64_t> Diff = 4306 getOffsetDifferenceInBits(*this, CountFD, FAMDecl)) { 4307 CharUnits OffsetDiff = CGM.getContext().toCharUnitsFromBits(*Diff); 4308 4309 // Create a GEP with a byte offset between the FAM and count and 4310 // use that to load the count value. 4311 Addr = Builder.CreatePointerBitCastOrAddrSpaceCast( 4312 ArrayLV.getAddress(), Int8PtrTy, Int8Ty); 4313 4314 llvm::Type *CountTy = ConvertType(CountFD->getType()); 4315 llvm::Value *Res = Builder.CreateInBoundsGEP( 4316 Int8Ty, Addr.emitRawPointer(*this), 4317 Builder.getInt32(OffsetDiff.getQuantity()), ".counted_by.gep"); 4318 Res = Builder.CreateAlignedLoad(CountTy, Res, getIntAlign(), 4319 ".counted_by.load"); 4320 4321 // Now emit the bounds checking. 4322 EmitBoundsCheckImpl(E, Res, Idx, E->getIdx()->getType(), 4323 Array->getType(), Accessed); 4324 } 4325 } 4326 } 4327 } 4328 4329 // Propagate the alignment from the array itself to the result. 4330 QualType arrayType = Array->getType(); 4331 Addr = emitArraySubscriptGEP( 4332 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx}, 4333 E->getType(), !getLangOpts().isSignedOverflowDefined(), SignedIndices, 4334 E->getExprLoc(), &arrayType, E->getBase()); 4335 EltBaseInfo = ArrayLV.getBaseInfo(); 4336 EltTBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, E->getType()); 4337 } else { 4338 // The base must be a pointer; emit it with an estimate of its alignment. 4339 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo); 4340 auto *Idx = EmitIdxAfterBase(/*Promote*/true); 4341 QualType ptrType = E->getBase()->getType(); 4342 Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(), 4343 !getLangOpts().isSignedOverflowDefined(), 4344 SignedIndices, E->getExprLoc(), &ptrType, 4345 E->getBase()); 4346 } 4347 4348 LValue LV = MakeAddrLValue(Addr, E->getType(), EltBaseInfo, EltTBAAInfo); 4349 4350 if (getLangOpts().ObjC && 4351 getLangOpts().getGC() != LangOptions::NonGC) { 4352 LV.setNonGC(!E->isOBJCGCCandidate(getContext())); 4353 setObjCGCLValueClass(getContext(), E, LV); 4354 } 4355 return LV; 4356 } 4357 4358 LValue CodeGenFunction::EmitMatrixSubscriptExpr(const MatrixSubscriptExpr *E) { 4359 assert( 4360 !E->isIncomplete() && 4361 "incomplete matrix subscript expressions should be rejected during Sema"); 4362 LValue Base = EmitLValue(E->getBase()); 4363 llvm::Value *RowIdx = EmitScalarExpr(E->getRowIdx()); 4364 llvm::Value *ColIdx = EmitScalarExpr(E->getColumnIdx()); 4365 llvm::Value *NumRows = Builder.getIntN( 4366 RowIdx->getType()->getScalarSizeInBits(), 4367 E->getBase()->getType()->castAs<ConstantMatrixType>()->getNumRows()); 4368 llvm::Value *FinalIdx = 4369 Builder.CreateAdd(Builder.CreateMul(ColIdx, NumRows), RowIdx); 4370 return LValue::MakeMatrixElt( 4371 MaybeConvertMatrixAddress(Base.getAddress(), *this), FinalIdx, 4372 E->getBase()->getType(), Base.getBaseInfo(), TBAAAccessInfo()); 4373 } 4374 4375 static Address emitOMPArraySectionBase(CodeGenFunction &CGF, const Expr *Base, 4376 LValueBaseInfo &BaseInfo, 4377 TBAAAccessInfo &TBAAInfo, 4378 QualType BaseTy, QualType ElTy, 4379 bool IsLowerBound) { 4380 LValue BaseLVal; 4381 if (auto *ASE = dyn_cast<ArraySectionExpr>(Base->IgnoreParenImpCasts())) { 4382 BaseLVal = CGF.EmitArraySectionExpr(ASE, IsLowerBound); 4383 if (BaseTy->isArrayType()) { 4384 Address Addr = BaseLVal.getAddress(); 4385 BaseInfo = BaseLVal.getBaseInfo(); 4386 4387 // If the array type was an incomplete type, we need to make sure 4388 // the decay ends up being the right type. 4389 llvm::Type *NewTy = CGF.ConvertType(BaseTy); 4390 Addr = Addr.withElementType(NewTy); 4391 4392 // Note that VLA pointers are always decayed, so we don't need to do 4393 // anything here. 4394 if (!BaseTy->isVariableArrayType()) { 4395 assert(isa<llvm::ArrayType>(Addr.getElementType()) && 4396 "Expected pointer to array"); 4397 Addr = CGF.Builder.CreateConstArrayGEP(Addr, 0, "arraydecay"); 4398 } 4399 4400 return Addr.withElementType(CGF.ConvertTypeForMem(ElTy)); 4401 } 4402 LValueBaseInfo TypeBaseInfo; 4403 TBAAAccessInfo TypeTBAAInfo; 4404 CharUnits Align = 4405 CGF.CGM.getNaturalTypeAlignment(ElTy, &TypeBaseInfo, &TypeTBAAInfo); 4406 BaseInfo.mergeForCast(TypeBaseInfo); 4407 TBAAInfo = CGF.CGM.mergeTBAAInfoForCast(TBAAInfo, TypeTBAAInfo); 4408 return Address(CGF.Builder.CreateLoad(BaseLVal.getAddress()), 4409 CGF.ConvertTypeForMem(ElTy), Align); 4410 } 4411 return CGF.EmitPointerWithAlignment(Base, &BaseInfo, &TBAAInfo); 4412 } 4413 4414 LValue CodeGenFunction::EmitArraySectionExpr(const ArraySectionExpr *E, 4415 bool IsLowerBound) { 4416 4417 assert(!E->isOpenACCArraySection() && 4418 "OpenACC Array section codegen not implemented"); 4419 4420 QualType BaseTy = ArraySectionExpr::getBaseOriginalType(E->getBase()); 4421 QualType ResultExprTy; 4422 if (auto *AT = getContext().getAsArrayType(BaseTy)) 4423 ResultExprTy = AT->getElementType(); 4424 else 4425 ResultExprTy = BaseTy->getPointeeType(); 4426 llvm::Value *Idx = nullptr; 4427 if (IsLowerBound || E->getColonLocFirst().isInvalid()) { 4428 // Requesting lower bound or upper bound, but without provided length and 4429 // without ':' symbol for the default length -> length = 1. 4430 // Idx = LowerBound ?: 0; 4431 if (auto *LowerBound = E->getLowerBound()) { 4432 Idx = Builder.CreateIntCast( 4433 EmitScalarExpr(LowerBound), IntPtrTy, 4434 LowerBound->getType()->hasSignedIntegerRepresentation()); 4435 } else 4436 Idx = llvm::ConstantInt::getNullValue(IntPtrTy); 4437 } else { 4438 // Try to emit length or lower bound as constant. If this is possible, 1 4439 // is subtracted from constant length or lower bound. Otherwise, emit LLVM 4440 // IR (LB + Len) - 1. 4441 auto &C = CGM.getContext(); 4442 auto *Length = E->getLength(); 4443 llvm::APSInt ConstLength; 4444 if (Length) { 4445 // Idx = LowerBound + Length - 1; 4446 if (std::optional<llvm::APSInt> CL = Length->getIntegerConstantExpr(C)) { 4447 ConstLength = CL->zextOrTrunc(PointerWidthInBits); 4448 Length = nullptr; 4449 } 4450 auto *LowerBound = E->getLowerBound(); 4451 llvm::APSInt ConstLowerBound(PointerWidthInBits, /*isUnsigned=*/false); 4452 if (LowerBound) { 4453 if (std::optional<llvm::APSInt> LB = 4454 LowerBound->getIntegerConstantExpr(C)) { 4455 ConstLowerBound = LB->zextOrTrunc(PointerWidthInBits); 4456 LowerBound = nullptr; 4457 } 4458 } 4459 if (!Length) 4460 --ConstLength; 4461 else if (!LowerBound) 4462 --ConstLowerBound; 4463 4464 if (Length || LowerBound) { 4465 auto *LowerBoundVal = 4466 LowerBound 4467 ? Builder.CreateIntCast( 4468 EmitScalarExpr(LowerBound), IntPtrTy, 4469 LowerBound->getType()->hasSignedIntegerRepresentation()) 4470 : llvm::ConstantInt::get(IntPtrTy, ConstLowerBound); 4471 auto *LengthVal = 4472 Length 4473 ? Builder.CreateIntCast( 4474 EmitScalarExpr(Length), IntPtrTy, 4475 Length->getType()->hasSignedIntegerRepresentation()) 4476 : llvm::ConstantInt::get(IntPtrTy, ConstLength); 4477 Idx = Builder.CreateAdd(LowerBoundVal, LengthVal, "lb_add_len", 4478 /*HasNUW=*/false, 4479 !getLangOpts().isSignedOverflowDefined()); 4480 if (Length && LowerBound) { 4481 Idx = Builder.CreateSub( 4482 Idx, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "idx_sub_1", 4483 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined()); 4484 } 4485 } else 4486 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength + ConstLowerBound); 4487 } else { 4488 // Idx = ArraySize - 1; 4489 QualType ArrayTy = BaseTy->isPointerType() 4490 ? E->getBase()->IgnoreParenImpCasts()->getType() 4491 : BaseTy; 4492 if (auto *VAT = C.getAsVariableArrayType(ArrayTy)) { 4493 Length = VAT->getSizeExpr(); 4494 if (std::optional<llvm::APSInt> L = Length->getIntegerConstantExpr(C)) { 4495 ConstLength = *L; 4496 Length = nullptr; 4497 } 4498 } else { 4499 auto *CAT = C.getAsConstantArrayType(ArrayTy); 4500 assert(CAT && "unexpected type for array initializer"); 4501 ConstLength = CAT->getSize(); 4502 } 4503 if (Length) { 4504 auto *LengthVal = Builder.CreateIntCast( 4505 EmitScalarExpr(Length), IntPtrTy, 4506 Length->getType()->hasSignedIntegerRepresentation()); 4507 Idx = Builder.CreateSub( 4508 LengthVal, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "len_sub_1", 4509 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined()); 4510 } else { 4511 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits); 4512 --ConstLength; 4513 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength); 4514 } 4515 } 4516 } 4517 assert(Idx); 4518 4519 Address EltPtr = Address::invalid(); 4520 LValueBaseInfo BaseInfo; 4521 TBAAAccessInfo TBAAInfo; 4522 if (auto *VLA = getContext().getAsVariableArrayType(ResultExprTy)) { 4523 // The base must be a pointer, which is not an aggregate. Emit 4524 // it. It needs to be emitted first in case it's what captures 4525 // the VLA bounds. 4526 Address Base = 4527 emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, TBAAInfo, 4528 BaseTy, VLA->getElementType(), IsLowerBound); 4529 // The element count here is the total number of non-VLA elements. 4530 llvm::Value *NumElements = getVLASize(VLA).NumElts; 4531 4532 // Effectively, the multiply by the VLA size is part of the GEP. 4533 // GEP indexes are signed, and scaling an index isn't permitted to 4534 // signed-overflow, so we use the same semantics for our explicit 4535 // multiply. We suppress this if overflow is not undefined behavior. 4536 if (getLangOpts().isSignedOverflowDefined()) 4537 Idx = Builder.CreateMul(Idx, NumElements); 4538 else 4539 Idx = Builder.CreateNSWMul(Idx, NumElements); 4540 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(), 4541 !getLangOpts().isSignedOverflowDefined(), 4542 /*signedIndices=*/false, E->getExprLoc()); 4543 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) { 4544 // If this is A[i] where A is an array, the frontend will have decayed the 4545 // base to be a ArrayToPointerDecay implicit cast. While correct, it is 4546 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a 4547 // "gep x, i" here. Emit one "gep A, 0, i". 4548 assert(Array->getType()->isArrayType() && 4549 "Array to pointer decay must have array source type!"); 4550 LValue ArrayLV; 4551 // For simple multidimensional array indexing, set the 'accessed' flag for 4552 // better bounds-checking of the base expression. 4553 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array)) 4554 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true); 4555 else 4556 ArrayLV = EmitLValue(Array); 4557 4558 // Propagate the alignment from the array itself to the result. 4559 EltPtr = emitArraySubscriptGEP( 4560 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx}, 4561 ResultExprTy, !getLangOpts().isSignedOverflowDefined(), 4562 /*signedIndices=*/false, E->getExprLoc()); 4563 BaseInfo = ArrayLV.getBaseInfo(); 4564 TBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, ResultExprTy); 4565 } else { 4566 Address Base = 4567 emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, TBAAInfo, BaseTy, 4568 ResultExprTy, IsLowerBound); 4569 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy, 4570 !getLangOpts().isSignedOverflowDefined(), 4571 /*signedIndices=*/false, E->getExprLoc()); 4572 } 4573 4574 return MakeAddrLValue(EltPtr, ResultExprTy, BaseInfo, TBAAInfo); 4575 } 4576 4577 LValue CodeGenFunction:: 4578 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) { 4579 // Emit the base vector as an l-value. 4580 LValue Base; 4581 4582 // ExtVectorElementExpr's base can either be a vector or pointer to vector. 4583 if (E->isArrow()) { 4584 // If it is a pointer to a vector, emit the address and form an lvalue with 4585 // it. 4586 LValueBaseInfo BaseInfo; 4587 TBAAAccessInfo TBAAInfo; 4588 Address Ptr = EmitPointerWithAlignment(E->getBase(), &BaseInfo, &TBAAInfo); 4589 const auto *PT = E->getBase()->getType()->castAs<PointerType>(); 4590 Base = MakeAddrLValue(Ptr, PT->getPointeeType(), BaseInfo, TBAAInfo); 4591 Base.getQuals().removeObjCGCAttr(); 4592 } else if (E->getBase()->isGLValue()) { 4593 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x), 4594 // emit the base as an lvalue. 4595 assert(E->getBase()->getType()->isVectorType()); 4596 Base = EmitLValue(E->getBase()); 4597 } else { 4598 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such. 4599 assert(E->getBase()->getType()->isVectorType() && 4600 "Result must be a vector"); 4601 llvm::Value *Vec = EmitScalarExpr(E->getBase()); 4602 4603 // Store the vector to memory (because LValue wants an address). 4604 Address VecMem = CreateMemTemp(E->getBase()->getType()); 4605 Builder.CreateStore(Vec, VecMem); 4606 Base = MakeAddrLValue(VecMem, E->getBase()->getType(), 4607 AlignmentSource::Decl); 4608 } 4609 4610 QualType type = 4611 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers()); 4612 4613 // Encode the element access list into a vector of unsigned indices. 4614 SmallVector<uint32_t, 4> Indices; 4615 E->getEncodedElementAccess(Indices); 4616 4617 if (Base.isSimple()) { 4618 llvm::Constant *CV = 4619 llvm::ConstantDataVector::get(getLLVMContext(), Indices); 4620 return LValue::MakeExtVectorElt(Base.getAddress(), CV, type, 4621 Base.getBaseInfo(), TBAAAccessInfo()); 4622 } 4623 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!"); 4624 4625 llvm::Constant *BaseElts = Base.getExtVectorElts(); 4626 SmallVector<llvm::Constant *, 4> CElts; 4627 4628 for (unsigned i = 0, e = Indices.size(); i != e; ++i) 4629 CElts.push_back(BaseElts->getAggregateElement(Indices[i])); 4630 llvm::Constant *CV = llvm::ConstantVector::get(CElts); 4631 return LValue::MakeExtVectorElt(Base.getExtVectorAddress(), CV, type, 4632 Base.getBaseInfo(), TBAAAccessInfo()); 4633 } 4634 4635 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) { 4636 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, E)) { 4637 EmitIgnoredExpr(E->getBase()); 4638 return EmitDeclRefLValue(DRE); 4639 } 4640 4641 Expr *BaseExpr = E->getBase(); 4642 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar. 4643 LValue BaseLV; 4644 if (E->isArrow()) { 4645 LValueBaseInfo BaseInfo; 4646 TBAAAccessInfo TBAAInfo; 4647 Address Addr = EmitPointerWithAlignment(BaseExpr, &BaseInfo, &TBAAInfo); 4648 QualType PtrTy = BaseExpr->getType()->getPointeeType(); 4649 SanitizerSet SkippedChecks; 4650 bool IsBaseCXXThis = IsWrappedCXXThis(BaseExpr); 4651 if (IsBaseCXXThis) 4652 SkippedChecks.set(SanitizerKind::Alignment, true); 4653 if (IsBaseCXXThis || isa<DeclRefExpr>(BaseExpr)) 4654 SkippedChecks.set(SanitizerKind::Null, true); 4655 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr, PtrTy, 4656 /*Alignment=*/CharUnits::Zero(), SkippedChecks); 4657 BaseLV = MakeAddrLValue(Addr, PtrTy, BaseInfo, TBAAInfo); 4658 } else 4659 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess); 4660 4661 NamedDecl *ND = E->getMemberDecl(); 4662 if (auto *Field = dyn_cast<FieldDecl>(ND)) { 4663 LValue LV = EmitLValueForField(BaseLV, Field); 4664 setObjCGCLValueClass(getContext(), E, LV); 4665 if (getLangOpts().OpenMP) { 4666 // If the member was explicitly marked as nontemporal, mark it as 4667 // nontemporal. If the base lvalue is marked as nontemporal, mark access 4668 // to children as nontemporal too. 4669 if ((IsWrappedCXXThis(BaseExpr) && 4670 CGM.getOpenMPRuntime().isNontemporalDecl(Field)) || 4671 BaseLV.isNontemporal()) 4672 LV.setNontemporal(/*Value=*/true); 4673 } 4674 return LV; 4675 } 4676 4677 if (const auto *FD = dyn_cast<FunctionDecl>(ND)) 4678 return EmitFunctionDeclLValue(*this, E, FD); 4679 4680 llvm_unreachable("Unhandled member declaration!"); 4681 } 4682 4683 /// Given that we are currently emitting a lambda, emit an l-value for 4684 /// one of its members. 4685 /// 4686 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field, 4687 llvm::Value *ThisValue) { 4688 bool HasExplicitObjectParameter = false; 4689 const auto *MD = dyn_cast_if_present<CXXMethodDecl>(CurCodeDecl); 4690 if (MD) { 4691 HasExplicitObjectParameter = MD->isExplicitObjectMemberFunction(); 4692 assert(MD->getParent()->isLambda()); 4693 assert(MD->getParent() == Field->getParent()); 4694 } 4695 LValue LambdaLV; 4696 if (HasExplicitObjectParameter) { 4697 const VarDecl *D = cast<CXXMethodDecl>(CurCodeDecl)->getParamDecl(0); 4698 auto It = LocalDeclMap.find(D); 4699 assert(It != LocalDeclMap.end() && "explicit parameter not loaded?"); 4700 Address AddrOfExplicitObject = It->getSecond(); 4701 if (D->getType()->isReferenceType()) 4702 LambdaLV = EmitLoadOfReferenceLValue(AddrOfExplicitObject, D->getType(), 4703 AlignmentSource::Decl); 4704 else 4705 LambdaLV = MakeAddrLValue(AddrOfExplicitObject, 4706 D->getType().getNonReferenceType()); 4707 4708 // Make sure we have an lvalue to the lambda itself and not a derived class. 4709 auto *ThisTy = D->getType().getNonReferenceType()->getAsCXXRecordDecl(); 4710 auto *LambdaTy = cast<CXXRecordDecl>(Field->getParent()); 4711 if (ThisTy != LambdaTy) { 4712 const CXXCastPath &BasePathArray = getContext().LambdaCastPaths.at(MD); 4713 Address Base = GetAddressOfBaseClass( 4714 LambdaLV.getAddress(), ThisTy, BasePathArray.begin(), 4715 BasePathArray.end(), /*NullCheckValue=*/false, SourceLocation()); 4716 LambdaLV = MakeAddrLValue(Base, QualType{LambdaTy->getTypeForDecl(), 0}); 4717 } 4718 } else { 4719 QualType LambdaTagType = getContext().getTagDeclType(Field->getParent()); 4720 LambdaLV = MakeNaturalAlignAddrLValue(ThisValue, LambdaTagType); 4721 } 4722 return EmitLValueForField(LambdaLV, Field); 4723 } 4724 4725 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) { 4726 return EmitLValueForLambdaField(Field, CXXABIThisValue); 4727 } 4728 4729 /// Get the field index in the debug info. The debug info structure/union 4730 /// will ignore the unnamed bitfields. 4731 unsigned CodeGenFunction::getDebugInfoFIndex(const RecordDecl *Rec, 4732 unsigned FieldIndex) { 4733 unsigned I = 0, Skipped = 0; 4734 4735 for (auto *F : Rec->getDefinition()->fields()) { 4736 if (I == FieldIndex) 4737 break; 4738 if (F->isUnnamedBitField()) 4739 Skipped++; 4740 I++; 4741 } 4742 4743 return FieldIndex - Skipped; 4744 } 4745 4746 /// Get the address of a zero-sized field within a record. The resulting 4747 /// address doesn't necessarily have the right type. 4748 static Address emitAddrOfZeroSizeField(CodeGenFunction &CGF, Address Base, 4749 const FieldDecl *Field) { 4750 CharUnits Offset = CGF.getContext().toCharUnitsFromBits( 4751 CGF.getContext().getFieldOffset(Field)); 4752 if (Offset.isZero()) 4753 return Base; 4754 Base = Base.withElementType(CGF.Int8Ty); 4755 return CGF.Builder.CreateConstInBoundsByteGEP(Base, Offset); 4756 } 4757 4758 /// Drill down to the storage of a field without walking into 4759 /// reference types. 4760 /// 4761 /// The resulting address doesn't necessarily have the right type. 4762 static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base, 4763 const FieldDecl *field) { 4764 if (isEmptyFieldForLayout(CGF.getContext(), field)) 4765 return emitAddrOfZeroSizeField(CGF, base, field); 4766 4767 const RecordDecl *rec = field->getParent(); 4768 4769 unsigned idx = 4770 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field); 4771 4772 return CGF.Builder.CreateStructGEP(base, idx, field->getName()); 4773 } 4774 4775 static Address emitPreserveStructAccess(CodeGenFunction &CGF, LValue base, 4776 Address addr, const FieldDecl *field) { 4777 const RecordDecl *rec = field->getParent(); 4778 llvm::DIType *DbgInfo = CGF.getDebugInfo()->getOrCreateStandaloneType( 4779 base.getType(), rec->getLocation()); 4780 4781 unsigned idx = 4782 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field); 4783 4784 return CGF.Builder.CreatePreserveStructAccessIndex( 4785 addr, idx, CGF.getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo); 4786 } 4787 4788 static bool hasAnyVptr(const QualType Type, const ASTContext &Context) { 4789 const auto *RD = Type.getTypePtr()->getAsCXXRecordDecl(); 4790 if (!RD) 4791 return false; 4792 4793 if (RD->isDynamicClass()) 4794 return true; 4795 4796 for (const auto &Base : RD->bases()) 4797 if (hasAnyVptr(Base.getType(), Context)) 4798 return true; 4799 4800 for (const FieldDecl *Field : RD->fields()) 4801 if (hasAnyVptr(Field->getType(), Context)) 4802 return true; 4803 4804 return false; 4805 } 4806 4807 LValue CodeGenFunction::EmitLValueForField(LValue base, 4808 const FieldDecl *field) { 4809 LValueBaseInfo BaseInfo = base.getBaseInfo(); 4810 4811 if (field->isBitField()) { 4812 const CGRecordLayout &RL = 4813 CGM.getTypes().getCGRecordLayout(field->getParent()); 4814 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field); 4815 const bool UseVolatile = isAAPCS(CGM.getTarget()) && 4816 CGM.getCodeGenOpts().AAPCSBitfieldWidth && 4817 Info.VolatileStorageSize != 0 && 4818 field->getType() 4819 .withCVRQualifiers(base.getVRQualifiers()) 4820 .isVolatileQualified(); 4821 Address Addr = base.getAddress(); 4822 unsigned Idx = RL.getLLVMFieldNo(field); 4823 const RecordDecl *rec = field->getParent(); 4824 if (hasBPFPreserveStaticOffset(rec)) 4825 Addr = wrapWithBPFPreserveStaticOffset(*this, Addr); 4826 if (!UseVolatile) { 4827 if (!IsInPreservedAIRegion && 4828 (!getDebugInfo() || !rec->hasAttr<BPFPreserveAccessIndexAttr>())) { 4829 if (Idx != 0) 4830 // For structs, we GEP to the field that the record layout suggests. 4831 Addr = Builder.CreateStructGEP(Addr, Idx, field->getName()); 4832 } else { 4833 llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateRecordType( 4834 getContext().getRecordType(rec), rec->getLocation()); 4835 Addr = Builder.CreatePreserveStructAccessIndex( 4836 Addr, Idx, getDebugInfoFIndex(rec, field->getFieldIndex()), 4837 DbgInfo); 4838 } 4839 } 4840 const unsigned SS = 4841 UseVolatile ? Info.VolatileStorageSize : Info.StorageSize; 4842 // Get the access type. 4843 llvm::Type *FieldIntTy = llvm::Type::getIntNTy(getLLVMContext(), SS); 4844 Addr = Addr.withElementType(FieldIntTy); 4845 if (UseVolatile) { 4846 const unsigned VolatileOffset = Info.VolatileStorageOffset.getQuantity(); 4847 if (VolatileOffset) 4848 Addr = Builder.CreateConstInBoundsGEP(Addr, VolatileOffset); 4849 } 4850 4851 QualType fieldType = 4852 field->getType().withCVRQualifiers(base.getVRQualifiers()); 4853 // TODO: Support TBAA for bit fields. 4854 LValueBaseInfo FieldBaseInfo(BaseInfo.getAlignmentSource()); 4855 return LValue::MakeBitfield(Addr, Info, fieldType, FieldBaseInfo, 4856 TBAAAccessInfo()); 4857 } 4858 4859 // Fields of may-alias structures are may-alias themselves. 4860 // FIXME: this should get propagated down through anonymous structs 4861 // and unions. 4862 QualType FieldType = field->getType(); 4863 const RecordDecl *rec = field->getParent(); 4864 AlignmentSource BaseAlignSource = BaseInfo.getAlignmentSource(); 4865 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(BaseAlignSource)); 4866 TBAAAccessInfo FieldTBAAInfo; 4867 if (base.getTBAAInfo().isMayAlias() || 4868 rec->hasAttr<MayAliasAttr>() || FieldType->isVectorType()) { 4869 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo(); 4870 } else if (rec->isUnion()) { 4871 // TODO: Support TBAA for unions. 4872 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo(); 4873 } else { 4874 // If no base type been assigned for the base access, then try to generate 4875 // one for this base lvalue. 4876 FieldTBAAInfo = base.getTBAAInfo(); 4877 if (!FieldTBAAInfo.BaseType) { 4878 FieldTBAAInfo.BaseType = CGM.getTBAABaseTypeInfo(base.getType()); 4879 assert(!FieldTBAAInfo.Offset && 4880 "Nonzero offset for an access with no base type!"); 4881 } 4882 4883 // Adjust offset to be relative to the base type. 4884 const ASTRecordLayout &Layout = 4885 getContext().getASTRecordLayout(field->getParent()); 4886 unsigned CharWidth = getContext().getCharWidth(); 4887 if (FieldTBAAInfo.BaseType) 4888 FieldTBAAInfo.Offset += 4889 Layout.getFieldOffset(field->getFieldIndex()) / CharWidth; 4890 4891 // Update the final access type and size. 4892 FieldTBAAInfo.AccessType = CGM.getTBAATypeInfo(FieldType); 4893 FieldTBAAInfo.Size = 4894 getContext().getTypeSizeInChars(FieldType).getQuantity(); 4895 } 4896 4897 Address addr = base.getAddress(); 4898 if (hasBPFPreserveStaticOffset(rec)) 4899 addr = wrapWithBPFPreserveStaticOffset(*this, addr); 4900 if (auto *ClassDef = dyn_cast<CXXRecordDecl>(rec)) { 4901 if (CGM.getCodeGenOpts().StrictVTablePointers && 4902 ClassDef->isDynamicClass()) { 4903 // Getting to any field of dynamic object requires stripping dynamic 4904 // information provided by invariant.group. This is because accessing 4905 // fields may leak the real address of dynamic object, which could result 4906 // in miscompilation when leaked pointer would be compared. 4907 auto *stripped = 4908 Builder.CreateStripInvariantGroup(addr.emitRawPointer(*this)); 4909 addr = Address(stripped, addr.getElementType(), addr.getAlignment()); 4910 } 4911 } 4912 4913 unsigned RecordCVR = base.getVRQualifiers(); 4914 if (rec->isUnion()) { 4915 // For unions, there is no pointer adjustment. 4916 if (CGM.getCodeGenOpts().StrictVTablePointers && 4917 hasAnyVptr(FieldType, getContext())) 4918 // Because unions can easily skip invariant.barriers, we need to add 4919 // a barrier every time CXXRecord field with vptr is referenced. 4920 addr = Builder.CreateLaunderInvariantGroup(addr); 4921 4922 if (IsInPreservedAIRegion || 4923 (getDebugInfo() && rec->hasAttr<BPFPreserveAccessIndexAttr>())) { 4924 // Remember the original union field index 4925 llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateStandaloneType(base.getType(), 4926 rec->getLocation()); 4927 addr = 4928 Address(Builder.CreatePreserveUnionAccessIndex( 4929 addr.emitRawPointer(*this), 4930 getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo), 4931 addr.getElementType(), addr.getAlignment()); 4932 } 4933 4934 if (FieldType->isReferenceType()) 4935 addr = addr.withElementType(CGM.getTypes().ConvertTypeForMem(FieldType)); 4936 } else { 4937 if (!IsInPreservedAIRegion && 4938 (!getDebugInfo() || !rec->hasAttr<BPFPreserveAccessIndexAttr>())) 4939 // For structs, we GEP to the field that the record layout suggests. 4940 addr = emitAddrOfFieldStorage(*this, addr, field); 4941 else 4942 // Remember the original struct field index 4943 addr = emitPreserveStructAccess(*this, base, addr, field); 4944 } 4945 4946 // If this is a reference field, load the reference right now. 4947 if (FieldType->isReferenceType()) { 4948 LValue RefLVal = 4949 MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo); 4950 if (RecordCVR & Qualifiers::Volatile) 4951 RefLVal.getQuals().addVolatile(); 4952 addr = EmitLoadOfReference(RefLVal, &FieldBaseInfo, &FieldTBAAInfo); 4953 4954 // Qualifiers on the struct don't apply to the referencee. 4955 RecordCVR = 0; 4956 FieldType = FieldType->getPointeeType(); 4957 } 4958 4959 // Make sure that the address is pointing to the right type. This is critical 4960 // for both unions and structs. 4961 addr = addr.withElementType(CGM.getTypes().ConvertTypeForMem(FieldType)); 4962 4963 if (field->hasAttr<AnnotateAttr>()) 4964 addr = EmitFieldAnnotations(field, addr); 4965 4966 LValue LV = MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo); 4967 LV.getQuals().addCVRQualifiers(RecordCVR); 4968 4969 // __weak attribute on a field is ignored. 4970 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak) 4971 LV.getQuals().removeObjCGCAttr(); 4972 4973 return LV; 4974 } 4975 4976 LValue 4977 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base, 4978 const FieldDecl *Field) { 4979 QualType FieldType = Field->getType(); 4980 4981 if (!FieldType->isReferenceType()) 4982 return EmitLValueForField(Base, Field); 4983 4984 Address V = emitAddrOfFieldStorage(*this, Base.getAddress(), Field); 4985 4986 // Make sure that the address is pointing to the right type. 4987 llvm::Type *llvmType = ConvertTypeForMem(FieldType); 4988 V = V.withElementType(llvmType); 4989 4990 // TODO: Generate TBAA information that describes this access as a structure 4991 // member access and not just an access to an object of the field's type. This 4992 // should be similar to what we do in EmitLValueForField(). 4993 LValueBaseInfo BaseInfo = Base.getBaseInfo(); 4994 AlignmentSource FieldAlignSource = BaseInfo.getAlignmentSource(); 4995 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(FieldAlignSource)); 4996 return MakeAddrLValue(V, FieldType, FieldBaseInfo, 4997 CGM.getTBAAInfoForSubobject(Base, FieldType)); 4998 } 4999 5000 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){ 5001 if (E->isFileScope()) { 5002 ConstantAddress GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E); 5003 return MakeAddrLValue(GlobalPtr, E->getType(), AlignmentSource::Decl); 5004 } 5005 if (E->getType()->isVariablyModifiedType()) 5006 // make sure to emit the VLA size. 5007 EmitVariablyModifiedType(E->getType()); 5008 5009 Address DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral"); 5010 const Expr *InitExpr = E->getInitializer(); 5011 LValue Result = MakeAddrLValue(DeclPtr, E->getType(), AlignmentSource::Decl); 5012 5013 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(), 5014 /*Init*/ true); 5015 5016 // Block-scope compound literals are destroyed at the end of the enclosing 5017 // scope in C. 5018 if (!getLangOpts().CPlusPlus) 5019 if (QualType::DestructionKind DtorKind = E->getType().isDestructedType()) 5020 pushLifetimeExtendedDestroy(getCleanupKind(DtorKind), DeclPtr, 5021 E->getType(), getDestroyer(DtorKind), 5022 DtorKind & EHCleanup); 5023 5024 return Result; 5025 } 5026 5027 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) { 5028 if (!E->isGLValue()) 5029 // Initializing an aggregate temporary in C++11: T{...}. 5030 return EmitAggExprToLValue(E); 5031 5032 // An lvalue initializer list must be initializing a reference. 5033 assert(E->isTransparent() && "non-transparent glvalue init list"); 5034 return EmitLValue(E->getInit(0)); 5035 } 5036 5037 /// Emit the operand of a glvalue conditional operator. This is either a glvalue 5038 /// or a (possibly-parenthesized) throw-expression. If this is a throw, no 5039 /// LValue is returned and the current block has been terminated. 5040 static std::optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF, 5041 const Expr *Operand) { 5042 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) { 5043 CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false); 5044 return std::nullopt; 5045 } 5046 5047 return CGF.EmitLValue(Operand); 5048 } 5049 5050 namespace { 5051 // Handle the case where the condition is a constant evaluatable simple integer, 5052 // which means we don't have to separately handle the true/false blocks. 5053 std::optional<LValue> HandleConditionalOperatorLValueSimpleCase( 5054 CodeGenFunction &CGF, const AbstractConditionalOperator *E) { 5055 const Expr *condExpr = E->getCond(); 5056 bool CondExprBool; 5057 if (CGF.ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) { 5058 const Expr *Live = E->getTrueExpr(), *Dead = E->getFalseExpr(); 5059 if (!CondExprBool) 5060 std::swap(Live, Dead); 5061 5062 if (!CGF.ContainsLabel(Dead)) { 5063 // If the true case is live, we need to track its region. 5064 if (CondExprBool) 5065 CGF.incrementProfileCounter(E); 5066 // If a throw expression we emit it and return an undefined lvalue 5067 // because it can't be used. 5068 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Live->IgnoreParens())) { 5069 CGF.EmitCXXThrowExpr(ThrowExpr); 5070 llvm::Type *ElemTy = CGF.ConvertType(Dead->getType()); 5071 llvm::Type *Ty = CGF.UnqualPtrTy; 5072 return CGF.MakeAddrLValue( 5073 Address(llvm::UndefValue::get(Ty), ElemTy, CharUnits::One()), 5074 Dead->getType()); 5075 } 5076 return CGF.EmitLValue(Live); 5077 } 5078 } 5079 return std::nullopt; 5080 } 5081 struct ConditionalInfo { 5082 llvm::BasicBlock *lhsBlock, *rhsBlock; 5083 std::optional<LValue> LHS, RHS; 5084 }; 5085 5086 // Create and generate the 3 blocks for a conditional operator. 5087 // Leaves the 'current block' in the continuation basic block. 5088 template<typename FuncTy> 5089 ConditionalInfo EmitConditionalBlocks(CodeGenFunction &CGF, 5090 const AbstractConditionalOperator *E, 5091 const FuncTy &BranchGenFunc) { 5092 ConditionalInfo Info{CGF.createBasicBlock("cond.true"), 5093 CGF.createBasicBlock("cond.false"), std::nullopt, 5094 std::nullopt}; 5095 llvm::BasicBlock *endBlock = CGF.createBasicBlock("cond.end"); 5096 5097 CodeGenFunction::ConditionalEvaluation eval(CGF); 5098 CGF.EmitBranchOnBoolExpr(E->getCond(), Info.lhsBlock, Info.rhsBlock, 5099 CGF.getProfileCount(E)); 5100 5101 // Any temporaries created here are conditional. 5102 CGF.EmitBlock(Info.lhsBlock); 5103 CGF.incrementProfileCounter(E); 5104 eval.begin(CGF); 5105 Info.LHS = BranchGenFunc(CGF, E->getTrueExpr()); 5106 eval.end(CGF); 5107 Info.lhsBlock = CGF.Builder.GetInsertBlock(); 5108 5109 if (Info.LHS) 5110 CGF.Builder.CreateBr(endBlock); 5111 5112 // Any temporaries created here are conditional. 5113 CGF.EmitBlock(Info.rhsBlock); 5114 eval.begin(CGF); 5115 Info.RHS = BranchGenFunc(CGF, E->getFalseExpr()); 5116 eval.end(CGF); 5117 Info.rhsBlock = CGF.Builder.GetInsertBlock(); 5118 CGF.EmitBlock(endBlock); 5119 5120 return Info; 5121 } 5122 } // namespace 5123 5124 void CodeGenFunction::EmitIgnoredConditionalOperator( 5125 const AbstractConditionalOperator *E) { 5126 if (!E->isGLValue()) { 5127 // ?: here should be an aggregate. 5128 assert(hasAggregateEvaluationKind(E->getType()) && 5129 "Unexpected conditional operator!"); 5130 return (void)EmitAggExprToLValue(E); 5131 } 5132 5133 OpaqueValueMapping binding(*this, E); 5134 if (HandleConditionalOperatorLValueSimpleCase(*this, E)) 5135 return; 5136 5137 EmitConditionalBlocks(*this, E, [](CodeGenFunction &CGF, const Expr *E) { 5138 CGF.EmitIgnoredExpr(E); 5139 return LValue{}; 5140 }); 5141 } 5142 LValue CodeGenFunction::EmitConditionalOperatorLValue( 5143 const AbstractConditionalOperator *expr) { 5144 if (!expr->isGLValue()) { 5145 // ?: here should be an aggregate. 5146 assert(hasAggregateEvaluationKind(expr->getType()) && 5147 "Unexpected conditional operator!"); 5148 return EmitAggExprToLValue(expr); 5149 } 5150 5151 OpaqueValueMapping binding(*this, expr); 5152 if (std::optional<LValue> Res = 5153 HandleConditionalOperatorLValueSimpleCase(*this, expr)) 5154 return *Res; 5155 5156 ConditionalInfo Info = EmitConditionalBlocks( 5157 *this, expr, [](CodeGenFunction &CGF, const Expr *E) { 5158 return EmitLValueOrThrowExpression(CGF, E); 5159 }); 5160 5161 if ((Info.LHS && !Info.LHS->isSimple()) || 5162 (Info.RHS && !Info.RHS->isSimple())) 5163 return EmitUnsupportedLValue(expr, "conditional operator"); 5164 5165 if (Info.LHS && Info.RHS) { 5166 Address lhsAddr = Info.LHS->getAddress(); 5167 Address rhsAddr = Info.RHS->getAddress(); 5168 Address result = mergeAddressesInConditionalExpr( 5169 lhsAddr, rhsAddr, Info.lhsBlock, Info.rhsBlock, 5170 Builder.GetInsertBlock(), expr->getType()); 5171 AlignmentSource alignSource = 5172 std::max(Info.LHS->getBaseInfo().getAlignmentSource(), 5173 Info.RHS->getBaseInfo().getAlignmentSource()); 5174 TBAAAccessInfo TBAAInfo = CGM.mergeTBAAInfoForConditionalOperator( 5175 Info.LHS->getTBAAInfo(), Info.RHS->getTBAAInfo()); 5176 return MakeAddrLValue(result, expr->getType(), LValueBaseInfo(alignSource), 5177 TBAAInfo); 5178 } else { 5179 assert((Info.LHS || Info.RHS) && 5180 "both operands of glvalue conditional are throw-expressions?"); 5181 return Info.LHS ? *Info.LHS : *Info.RHS; 5182 } 5183 } 5184 5185 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference 5186 /// type. If the cast is to a reference, we can have the usual lvalue result, 5187 /// otherwise if a cast is needed by the code generator in an lvalue context, 5188 /// then it must mean that we need the address of an aggregate in order to 5189 /// access one of its members. This can happen for all the reasons that casts 5190 /// are permitted with aggregate result, including noop aggregate casts, and 5191 /// cast from scalar to union. 5192 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) { 5193 switch (E->getCastKind()) { 5194 case CK_ToVoid: 5195 case CK_BitCast: 5196 case CK_LValueToRValueBitCast: 5197 case CK_ArrayToPointerDecay: 5198 case CK_FunctionToPointerDecay: 5199 case CK_NullToMemberPointer: 5200 case CK_NullToPointer: 5201 case CK_IntegralToPointer: 5202 case CK_PointerToIntegral: 5203 case CK_PointerToBoolean: 5204 case CK_IntegralCast: 5205 case CK_BooleanToSignedIntegral: 5206 case CK_IntegralToBoolean: 5207 case CK_IntegralToFloating: 5208 case CK_FloatingToIntegral: 5209 case CK_FloatingToBoolean: 5210 case CK_FloatingCast: 5211 case CK_FloatingRealToComplex: 5212 case CK_FloatingComplexToReal: 5213 case CK_FloatingComplexToBoolean: 5214 case CK_FloatingComplexCast: 5215 case CK_FloatingComplexToIntegralComplex: 5216 case CK_IntegralRealToComplex: 5217 case CK_IntegralComplexToReal: 5218 case CK_IntegralComplexToBoolean: 5219 case CK_IntegralComplexCast: 5220 case CK_IntegralComplexToFloatingComplex: 5221 case CK_DerivedToBaseMemberPointer: 5222 case CK_BaseToDerivedMemberPointer: 5223 case CK_MemberPointerToBoolean: 5224 case CK_ReinterpretMemberPointer: 5225 case CK_AnyPointerToBlockPointerCast: 5226 case CK_ARCProduceObject: 5227 case CK_ARCConsumeObject: 5228 case CK_ARCReclaimReturnedObject: 5229 case CK_ARCExtendBlockObject: 5230 case CK_CopyAndAutoreleaseBlockObject: 5231 case CK_IntToOCLSampler: 5232 case CK_FloatingToFixedPoint: 5233 case CK_FixedPointToFloating: 5234 case CK_FixedPointCast: 5235 case CK_FixedPointToBoolean: 5236 case CK_FixedPointToIntegral: 5237 case CK_IntegralToFixedPoint: 5238 case CK_MatrixCast: 5239 case CK_HLSLVectorTruncation: 5240 case CK_HLSLArrayRValue: 5241 return EmitUnsupportedLValue(E, "unexpected cast lvalue"); 5242 5243 case CK_Dependent: 5244 llvm_unreachable("dependent cast kind in IR gen!"); 5245 5246 case CK_BuiltinFnToFnPtr: 5247 llvm_unreachable("builtin functions are handled elsewhere"); 5248 5249 // These are never l-values; just use the aggregate emission code. 5250 case CK_NonAtomicToAtomic: 5251 case CK_AtomicToNonAtomic: 5252 return EmitAggExprToLValue(E); 5253 5254 case CK_Dynamic: { 5255 LValue LV = EmitLValue(E->getSubExpr()); 5256 Address V = LV.getAddress(); 5257 const auto *DCE = cast<CXXDynamicCastExpr>(E); 5258 return MakeNaturalAlignRawAddrLValue(EmitDynamicCast(V, DCE), E->getType()); 5259 } 5260 5261 case CK_ConstructorConversion: 5262 case CK_UserDefinedConversion: 5263 case CK_CPointerToObjCPointerCast: 5264 case CK_BlockPointerToObjCPointerCast: 5265 case CK_LValueToRValue: 5266 return EmitLValue(E->getSubExpr()); 5267 5268 case CK_NoOp: { 5269 // CK_NoOp can model a qualification conversion, which can remove an array 5270 // bound and change the IR type. 5271 // FIXME: Once pointee types are removed from IR, remove this. 5272 LValue LV = EmitLValue(E->getSubExpr()); 5273 // Propagate the volatile qualifer to LValue, if exist in E. 5274 if (E->changesVolatileQualification()) 5275 LV.getQuals() = E->getType().getQualifiers(); 5276 if (LV.isSimple()) { 5277 Address V = LV.getAddress(); 5278 if (V.isValid()) { 5279 llvm::Type *T = ConvertTypeForMem(E->getType()); 5280 if (V.getElementType() != T) 5281 LV.setAddress(V.withElementType(T)); 5282 } 5283 } 5284 return LV; 5285 } 5286 5287 case CK_UncheckedDerivedToBase: 5288 case CK_DerivedToBase: { 5289 const auto *DerivedClassTy = 5290 E->getSubExpr()->getType()->castAs<RecordType>(); 5291 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 5292 5293 LValue LV = EmitLValue(E->getSubExpr()); 5294 Address This = LV.getAddress(); 5295 5296 // Perform the derived-to-base conversion 5297 Address Base = GetAddressOfBaseClass( 5298 This, DerivedClassDecl, E->path_begin(), E->path_end(), 5299 /*NullCheckValue=*/false, E->getExprLoc()); 5300 5301 // TODO: Support accesses to members of base classes in TBAA. For now, we 5302 // conservatively pretend that the complete object is of the base class 5303 // type. 5304 return MakeAddrLValue(Base, E->getType(), LV.getBaseInfo(), 5305 CGM.getTBAAInfoForSubobject(LV, E->getType())); 5306 } 5307 case CK_ToUnion: 5308 return EmitAggExprToLValue(E); 5309 case CK_BaseToDerived: { 5310 const auto *DerivedClassTy = E->getType()->castAs<RecordType>(); 5311 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl()); 5312 5313 LValue LV = EmitLValue(E->getSubExpr()); 5314 5315 // Perform the base-to-derived conversion 5316 Address Derived = GetAddressOfDerivedClass( 5317 LV.getAddress(), DerivedClassDecl, E->path_begin(), E->path_end(), 5318 /*NullCheckValue=*/false); 5319 5320 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is 5321 // performed and the object is not of the derived type. 5322 if (sanitizePerformTypeCheck()) 5323 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(), Derived, 5324 E->getType()); 5325 5326 if (SanOpts.has(SanitizerKind::CFIDerivedCast)) 5327 EmitVTablePtrCheckForCast(E->getType(), Derived, 5328 /*MayBeNull=*/false, CFITCK_DerivedCast, 5329 E->getBeginLoc()); 5330 5331 return MakeAddrLValue(Derived, E->getType(), LV.getBaseInfo(), 5332 CGM.getTBAAInfoForSubobject(LV, E->getType())); 5333 } 5334 case CK_LValueBitCast: { 5335 // This must be a reinterpret_cast (or c-style equivalent). 5336 const auto *CE = cast<ExplicitCastExpr>(E); 5337 5338 CGM.EmitExplicitCastExprType(CE, this); 5339 LValue LV = EmitLValue(E->getSubExpr()); 5340 Address V = LV.getAddress().withElementType( 5341 ConvertTypeForMem(CE->getTypeAsWritten()->getPointeeType())); 5342 5343 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast)) 5344 EmitVTablePtrCheckForCast(E->getType(), V, 5345 /*MayBeNull=*/false, CFITCK_UnrelatedCast, 5346 E->getBeginLoc()); 5347 5348 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(), 5349 CGM.getTBAAInfoForSubobject(LV, E->getType())); 5350 } 5351 case CK_AddressSpaceConversion: { 5352 LValue LV = EmitLValue(E->getSubExpr()); 5353 QualType DestTy = getContext().getPointerType(E->getType()); 5354 llvm::Value *V = getTargetHooks().performAddrSpaceCast( 5355 *this, LV.getPointer(*this), 5356 E->getSubExpr()->getType().getAddressSpace(), 5357 E->getType().getAddressSpace(), ConvertType(DestTy)); 5358 return MakeAddrLValue(Address(V, ConvertTypeForMem(E->getType()), 5359 LV.getAddress().getAlignment()), 5360 E->getType(), LV.getBaseInfo(), LV.getTBAAInfo()); 5361 } 5362 case CK_ObjCObjectLValueCast: { 5363 LValue LV = EmitLValue(E->getSubExpr()); 5364 Address V = LV.getAddress().withElementType(ConvertType(E->getType())); 5365 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(), 5366 CGM.getTBAAInfoForSubobject(LV, E->getType())); 5367 } 5368 case CK_ZeroToOCLOpaqueType: 5369 llvm_unreachable("NULL to OpenCL opaque type lvalue cast is not valid"); 5370 5371 case CK_VectorSplat: { 5372 // LValue results of vector splats are only supported in HLSL. 5373 if (!getLangOpts().HLSL) 5374 return EmitUnsupportedLValue(E, "unexpected cast lvalue"); 5375 return EmitLValue(E->getSubExpr()); 5376 } 5377 } 5378 5379 llvm_unreachable("Unhandled lvalue cast kind?"); 5380 } 5381 5382 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) { 5383 assert(OpaqueValueMappingData::shouldBindAsLValue(e)); 5384 return getOrCreateOpaqueLValueMapping(e); 5385 } 5386 5387 LValue 5388 CodeGenFunction::getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e) { 5389 assert(OpaqueValueMapping::shouldBindAsLValue(e)); 5390 5391 llvm::DenseMap<const OpaqueValueExpr*,LValue>::iterator 5392 it = OpaqueLValues.find(e); 5393 5394 if (it != OpaqueLValues.end()) 5395 return it->second; 5396 5397 assert(e->isUnique() && "LValue for a nonunique OVE hasn't been emitted"); 5398 return EmitLValue(e->getSourceExpr()); 5399 } 5400 5401 RValue 5402 CodeGenFunction::getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e) { 5403 assert(!OpaqueValueMapping::shouldBindAsLValue(e)); 5404 5405 llvm::DenseMap<const OpaqueValueExpr*,RValue>::iterator 5406 it = OpaqueRValues.find(e); 5407 5408 if (it != OpaqueRValues.end()) 5409 return it->second; 5410 5411 assert(e->isUnique() && "RValue for a nonunique OVE hasn't been emitted"); 5412 return EmitAnyExpr(e->getSourceExpr()); 5413 } 5414 5415 RValue CodeGenFunction::EmitRValueForField(LValue LV, 5416 const FieldDecl *FD, 5417 SourceLocation Loc) { 5418 QualType FT = FD->getType(); 5419 LValue FieldLV = EmitLValueForField(LV, FD); 5420 switch (getEvaluationKind(FT)) { 5421 case TEK_Complex: 5422 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc)); 5423 case TEK_Aggregate: 5424 return FieldLV.asAggregateRValue(); 5425 case TEK_Scalar: 5426 // This routine is used to load fields one-by-one to perform a copy, so 5427 // don't load reference fields. 5428 if (FD->getType()->isReferenceType()) 5429 return RValue::get(FieldLV.getPointer(*this)); 5430 // Call EmitLoadOfScalar except when the lvalue is a bitfield to emit a 5431 // primitive load. 5432 if (FieldLV.isBitField()) 5433 return EmitLoadOfLValue(FieldLV, Loc); 5434 return RValue::get(EmitLoadOfScalar(FieldLV, Loc)); 5435 } 5436 llvm_unreachable("bad evaluation kind"); 5437 } 5438 5439 //===--------------------------------------------------------------------===// 5440 // Expression Emission 5441 //===--------------------------------------------------------------------===// 5442 5443 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E, 5444 ReturnValueSlot ReturnValue) { 5445 // Builtins never have block type. 5446 if (E->getCallee()->getType()->isBlockPointerType()) 5447 return EmitBlockCallExpr(E, ReturnValue); 5448 5449 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E)) 5450 return EmitCXXMemberCallExpr(CE, ReturnValue); 5451 5452 if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E)) 5453 return EmitCUDAKernelCallExpr(CE, ReturnValue); 5454 5455 // A CXXOperatorCallExpr is created even for explicit object methods, but 5456 // these should be treated like static function call. 5457 if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E)) 5458 if (const auto *MD = 5459 dyn_cast_if_present<CXXMethodDecl>(CE->getCalleeDecl()); 5460 MD && MD->isImplicitObjectMemberFunction()) 5461 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue); 5462 5463 CGCallee callee = EmitCallee(E->getCallee()); 5464 5465 if (callee.isBuiltin()) { 5466 return EmitBuiltinExpr(callee.getBuiltinDecl(), callee.getBuiltinID(), 5467 E, ReturnValue); 5468 } 5469 5470 if (callee.isPseudoDestructor()) { 5471 return EmitCXXPseudoDestructorExpr(callee.getPseudoDestructorExpr()); 5472 } 5473 5474 return EmitCall(E->getCallee()->getType(), callee, E, ReturnValue); 5475 } 5476 5477 /// Emit a CallExpr without considering whether it might be a subclass. 5478 RValue CodeGenFunction::EmitSimpleCallExpr(const CallExpr *E, 5479 ReturnValueSlot ReturnValue) { 5480 CGCallee Callee = EmitCallee(E->getCallee()); 5481 return EmitCall(E->getCallee()->getType(), Callee, E, ReturnValue); 5482 } 5483 5484 // Detect the unusual situation where an inline version is shadowed by a 5485 // non-inline version. In that case we should pick the external one 5486 // everywhere. That's GCC behavior too. 5487 static bool OnlyHasInlineBuiltinDeclaration(const FunctionDecl *FD) { 5488 for (const FunctionDecl *PD = FD; PD; PD = PD->getPreviousDecl()) 5489 if (!PD->isInlineBuiltinDeclaration()) 5490 return false; 5491 return true; 5492 } 5493 5494 static CGCallee EmitDirectCallee(CodeGenFunction &CGF, GlobalDecl GD) { 5495 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 5496 5497 if (auto builtinID = FD->getBuiltinID()) { 5498 std::string NoBuiltinFD = ("no-builtin-" + FD->getName()).str(); 5499 std::string NoBuiltins = "no-builtins"; 5500 5501 StringRef Ident = CGF.CGM.getMangledName(GD); 5502 std::string FDInlineName = (Ident + ".inline").str(); 5503 5504 bool IsPredefinedLibFunction = 5505 CGF.getContext().BuiltinInfo.isPredefinedLibFunction(builtinID); 5506 bool HasAttributeNoBuiltin = 5507 CGF.CurFn->getAttributes().hasFnAttr(NoBuiltinFD) || 5508 CGF.CurFn->getAttributes().hasFnAttr(NoBuiltins); 5509 5510 // When directing calling an inline builtin, call it through it's mangled 5511 // name to make it clear it's not the actual builtin. 5512 if (CGF.CurFn->getName() != FDInlineName && 5513 OnlyHasInlineBuiltinDeclaration(FD)) { 5514 llvm::Constant *CalleePtr = CGF.CGM.getRawFunctionPointer(GD); 5515 llvm::Function *Fn = llvm::cast<llvm::Function>(CalleePtr); 5516 llvm::Module *M = Fn->getParent(); 5517 llvm::Function *Clone = M->getFunction(FDInlineName); 5518 if (!Clone) { 5519 Clone = llvm::Function::Create(Fn->getFunctionType(), 5520 llvm::GlobalValue::InternalLinkage, 5521 Fn->getAddressSpace(), FDInlineName, M); 5522 Clone->addFnAttr(llvm::Attribute::AlwaysInline); 5523 } 5524 return CGCallee::forDirect(Clone, GD); 5525 } 5526 5527 // Replaceable builtins provide their own implementation of a builtin. If we 5528 // are in an inline builtin implementation, avoid trivial infinite 5529 // recursion. Honor __attribute__((no_builtin("foo"))) or 5530 // __attribute__((no_builtin)) on the current function unless foo is 5531 // not a predefined library function which means we must generate the 5532 // builtin no matter what. 5533 else if (!IsPredefinedLibFunction || !HasAttributeNoBuiltin) 5534 return CGCallee::forBuiltin(builtinID, FD); 5535 } 5536 5537 llvm::Constant *CalleePtr = CGF.CGM.getRawFunctionPointer(GD); 5538 if (CGF.CGM.getLangOpts().CUDA && !CGF.CGM.getLangOpts().CUDAIsDevice && 5539 FD->hasAttr<CUDAGlobalAttr>()) 5540 CalleePtr = CGF.CGM.getCUDARuntime().getKernelStub( 5541 cast<llvm::GlobalValue>(CalleePtr->stripPointerCasts())); 5542 5543 return CGCallee::forDirect(CalleePtr, GD); 5544 } 5545 5546 CGCallee CodeGenFunction::EmitCallee(const Expr *E) { 5547 E = E->IgnoreParens(); 5548 5549 // Look through function-to-pointer decay. 5550 if (auto ICE = dyn_cast<ImplicitCastExpr>(E)) { 5551 if (ICE->getCastKind() == CK_FunctionToPointerDecay || 5552 ICE->getCastKind() == CK_BuiltinFnToFnPtr) { 5553 return EmitCallee(ICE->getSubExpr()); 5554 } 5555 5556 // Resolve direct calls. 5557 } else if (auto DRE = dyn_cast<DeclRefExpr>(E)) { 5558 if (auto FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 5559 return EmitDirectCallee(*this, FD); 5560 } 5561 } else if (auto ME = dyn_cast<MemberExpr>(E)) { 5562 if (auto FD = dyn_cast<FunctionDecl>(ME->getMemberDecl())) { 5563 EmitIgnoredExpr(ME->getBase()); 5564 return EmitDirectCallee(*this, FD); 5565 } 5566 5567 // Look through template substitutions. 5568 } else if (auto NTTP = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) { 5569 return EmitCallee(NTTP->getReplacement()); 5570 5571 // Treat pseudo-destructor calls differently. 5572 } else if (auto PDE = dyn_cast<CXXPseudoDestructorExpr>(E)) { 5573 return CGCallee::forPseudoDestructor(PDE); 5574 } 5575 5576 // Otherwise, we have an indirect reference. 5577 llvm::Value *calleePtr; 5578 QualType functionType; 5579 if (auto ptrType = E->getType()->getAs<PointerType>()) { 5580 calleePtr = EmitScalarExpr(E); 5581 functionType = ptrType->getPointeeType(); 5582 } else { 5583 functionType = E->getType(); 5584 calleePtr = EmitLValue(E, KnownNonNull).getPointer(*this); 5585 } 5586 assert(functionType->isFunctionType()); 5587 5588 GlobalDecl GD; 5589 if (const auto *VD = 5590 dyn_cast_or_null<VarDecl>(E->getReferencedDeclOfCallee())) 5591 GD = GlobalDecl(VD); 5592 5593 CGCalleeInfo calleeInfo(functionType->getAs<FunctionProtoType>(), GD); 5594 CGPointerAuthInfo pointerAuth = CGM.getFunctionPointerAuthInfo(functionType); 5595 CGCallee callee(calleeInfo, calleePtr, pointerAuth); 5596 return callee; 5597 } 5598 5599 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) { 5600 // Comma expressions just emit their LHS then their RHS as an l-value. 5601 if (E->getOpcode() == BO_Comma) { 5602 EmitIgnoredExpr(E->getLHS()); 5603 EnsureInsertPoint(); 5604 return EmitLValue(E->getRHS()); 5605 } 5606 5607 if (E->getOpcode() == BO_PtrMemD || 5608 E->getOpcode() == BO_PtrMemI) 5609 return EmitPointerToDataMemberBinaryExpr(E); 5610 5611 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value"); 5612 5613 // Note that in all of these cases, __block variables need the RHS 5614 // evaluated first just in case the variable gets moved by the RHS. 5615 5616 switch (getEvaluationKind(E->getType())) { 5617 case TEK_Scalar: { 5618 switch (E->getLHS()->getType().getObjCLifetime()) { 5619 case Qualifiers::OCL_Strong: 5620 return EmitARCStoreStrong(E, /*ignored*/ false).first; 5621 5622 case Qualifiers::OCL_Autoreleasing: 5623 return EmitARCStoreAutoreleasing(E).first; 5624 5625 // No reason to do any of these differently. 5626 case Qualifiers::OCL_None: 5627 case Qualifiers::OCL_ExplicitNone: 5628 case Qualifiers::OCL_Weak: 5629 break; 5630 } 5631 5632 // TODO: Can we de-duplicate this code with the corresponding code in 5633 // CGExprScalar, similar to the way EmitCompoundAssignmentLValue works? 5634 RValue RV; 5635 llvm::Value *Previous = nullptr; 5636 QualType SrcType = E->getRHS()->getType(); 5637 // Check if LHS is a bitfield, if RHS contains an implicit cast expression 5638 // we want to extract that value and potentially (if the bitfield sanitizer 5639 // is enabled) use it to check for an implicit conversion. 5640 if (E->getLHS()->refersToBitField()) { 5641 llvm::Value *RHS = 5642 EmitWithOriginalRHSBitfieldAssignment(E, &Previous, &SrcType); 5643 RV = RValue::get(RHS); 5644 } else 5645 RV = EmitAnyExpr(E->getRHS()); 5646 5647 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store); 5648 5649 if (RV.isScalar()) 5650 EmitNullabilityCheck(LV, RV.getScalarVal(), E->getExprLoc()); 5651 5652 if (LV.isBitField()) { 5653 llvm::Value *Result = nullptr; 5654 // If bitfield sanitizers are enabled we want to use the result 5655 // to check whether a truncation or sign change has occurred. 5656 if (SanOpts.has(SanitizerKind::ImplicitBitfieldConversion)) 5657 EmitStoreThroughBitfieldLValue(RV, LV, &Result); 5658 else 5659 EmitStoreThroughBitfieldLValue(RV, LV); 5660 5661 // If the expression contained an implicit conversion, make sure 5662 // to use the value before the scalar conversion. 5663 llvm::Value *Src = Previous ? Previous : RV.getScalarVal(); 5664 QualType DstType = E->getLHS()->getType(); 5665 EmitBitfieldConversionCheck(Src, SrcType, Result, DstType, 5666 LV.getBitFieldInfo(), E->getExprLoc()); 5667 } else 5668 EmitStoreThroughLValue(RV, LV); 5669 5670 if (getLangOpts().OpenMP) 5671 CGM.getOpenMPRuntime().checkAndEmitLastprivateConditional(*this, 5672 E->getLHS()); 5673 return LV; 5674 } 5675 5676 case TEK_Complex: 5677 return EmitComplexAssignmentLValue(E); 5678 5679 case TEK_Aggregate: 5680 return EmitAggExprToLValue(E); 5681 } 5682 llvm_unreachable("bad evaluation kind"); 5683 } 5684 5685 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) { 5686 RValue RV = EmitCallExpr(E); 5687 5688 if (!RV.isScalar()) 5689 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(), 5690 AlignmentSource::Decl); 5691 5692 assert(E->getCallReturnType(getContext())->isReferenceType() && 5693 "Can't have a scalar return unless the return type is a " 5694 "reference type!"); 5695 5696 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType()); 5697 } 5698 5699 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) { 5700 // FIXME: This shouldn't require another copy. 5701 return EmitAggExprToLValue(E); 5702 } 5703 5704 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) { 5705 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor() 5706 && "binding l-value to type which needs a temporary"); 5707 AggValueSlot Slot = CreateAggTemp(E->getType()); 5708 EmitCXXConstructExpr(E, Slot); 5709 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl); 5710 } 5711 5712 LValue 5713 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) { 5714 return MakeNaturalAlignRawAddrLValue(EmitCXXTypeidExpr(E), E->getType()); 5715 } 5716 5717 Address CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) { 5718 return CGM.GetAddrOfMSGuidDecl(E->getGuidDecl()) 5719 .withElementType(ConvertType(E->getType())); 5720 } 5721 5722 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) { 5723 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType(), 5724 AlignmentSource::Decl); 5725 } 5726 5727 LValue 5728 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) { 5729 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue"); 5730 Slot.setExternallyDestructed(); 5731 EmitAggExpr(E->getSubExpr(), Slot); 5732 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddress()); 5733 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl); 5734 } 5735 5736 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) { 5737 RValue RV = EmitObjCMessageExpr(E); 5738 5739 if (!RV.isScalar()) 5740 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(), 5741 AlignmentSource::Decl); 5742 5743 assert(E->getMethodDecl()->getReturnType()->isReferenceType() && 5744 "Can't have a scalar return unless the return type is a " 5745 "reference type!"); 5746 5747 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType()); 5748 } 5749 5750 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) { 5751 Address V = 5752 CGM.getObjCRuntime().GetAddrOfSelector(*this, E->getSelector()); 5753 return MakeAddrLValue(V, E->getType(), AlignmentSource::Decl); 5754 } 5755 5756 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface, 5757 const ObjCIvarDecl *Ivar) { 5758 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar); 5759 } 5760 5761 llvm::Value * 5762 CodeGenFunction::EmitIvarOffsetAsPointerDiff(const ObjCInterfaceDecl *Interface, 5763 const ObjCIvarDecl *Ivar) { 5764 llvm::Value *OffsetValue = EmitIvarOffset(Interface, Ivar); 5765 QualType PointerDiffType = getContext().getPointerDiffType(); 5766 return Builder.CreateZExtOrTrunc(OffsetValue, 5767 getTypes().ConvertType(PointerDiffType)); 5768 } 5769 5770 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy, 5771 llvm::Value *BaseValue, 5772 const ObjCIvarDecl *Ivar, 5773 unsigned CVRQualifiers) { 5774 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue, 5775 Ivar, CVRQualifiers); 5776 } 5777 5778 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) { 5779 // FIXME: A lot of the code below could be shared with EmitMemberExpr. 5780 llvm::Value *BaseValue = nullptr; 5781 const Expr *BaseExpr = E->getBase(); 5782 Qualifiers BaseQuals; 5783 QualType ObjectTy; 5784 if (E->isArrow()) { 5785 BaseValue = EmitScalarExpr(BaseExpr); 5786 ObjectTy = BaseExpr->getType()->getPointeeType(); 5787 BaseQuals = ObjectTy.getQualifiers(); 5788 } else { 5789 LValue BaseLV = EmitLValue(BaseExpr); 5790 BaseValue = BaseLV.getPointer(*this); 5791 ObjectTy = BaseExpr->getType(); 5792 BaseQuals = ObjectTy.getQualifiers(); 5793 } 5794 5795 LValue LV = 5796 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(), 5797 BaseQuals.getCVRQualifiers()); 5798 setObjCGCLValueClass(getContext(), E, LV); 5799 return LV; 5800 } 5801 5802 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) { 5803 // Can only get l-value for message expression returning aggregate type 5804 RValue RV = EmitAnyExprToTemp(E); 5805 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(), 5806 AlignmentSource::Decl); 5807 } 5808 5809 RValue CodeGenFunction::EmitCall(QualType CalleeType, const CGCallee &OrigCallee, 5810 const CallExpr *E, ReturnValueSlot ReturnValue, 5811 llvm::Value *Chain) { 5812 // Get the actual function type. The callee type will always be a pointer to 5813 // function type or a block pointer type. 5814 assert(CalleeType->isFunctionPointerType() && 5815 "Call must have function pointer type!"); 5816 5817 const Decl *TargetDecl = 5818 OrigCallee.getAbstractInfo().getCalleeDecl().getDecl(); 5819 5820 assert((!isa_and_present<FunctionDecl>(TargetDecl) || 5821 !cast<FunctionDecl>(TargetDecl)->isImmediateFunction()) && 5822 "trying to emit a call to an immediate function"); 5823 5824 CalleeType = getContext().getCanonicalType(CalleeType); 5825 5826 auto PointeeType = cast<PointerType>(CalleeType)->getPointeeType(); 5827 5828 CGCallee Callee = OrigCallee; 5829 5830 if (SanOpts.has(SanitizerKind::Function) && 5831 (!TargetDecl || !isa<FunctionDecl>(TargetDecl)) && 5832 !isa<FunctionNoProtoType>(PointeeType)) { 5833 if (llvm::Constant *PrefixSig = 5834 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) { 5835 SanitizerScope SanScope(this); 5836 auto *TypeHash = getUBSanFunctionTypeHash(PointeeType); 5837 5838 llvm::Type *PrefixSigType = PrefixSig->getType(); 5839 llvm::StructType *PrefixStructTy = llvm::StructType::get( 5840 CGM.getLLVMContext(), {PrefixSigType, Int32Ty}, /*isPacked=*/true); 5841 5842 llvm::Value *CalleePtr = Callee.getFunctionPointer(); 5843 if (CGM.getCodeGenOpts().PointerAuth.FunctionPointers) { 5844 // Use raw pointer since we are using the callee pointer as data here. 5845 Address Addr = 5846 Address(CalleePtr, CalleePtr->getType(), 5847 CharUnits::fromQuantity( 5848 CalleePtr->getPointerAlignment(CGM.getDataLayout())), 5849 Callee.getPointerAuthInfo(), nullptr); 5850 CalleePtr = Addr.emitRawPointer(*this); 5851 } 5852 5853 // On 32-bit Arm, the low bit of a function pointer indicates whether 5854 // it's using the Arm or Thumb instruction set. The actual first 5855 // instruction lives at the same address either way, so we must clear 5856 // that low bit before using the function address to find the prefix 5857 // structure. 5858 // 5859 // This applies to both Arm and Thumb target triples, because 5860 // either one could be used in an interworking context where it 5861 // might be passed function pointers of both types. 5862 llvm::Value *AlignedCalleePtr; 5863 if (CGM.getTriple().isARM() || CGM.getTriple().isThumb()) { 5864 llvm::Value *CalleeAddress = 5865 Builder.CreatePtrToInt(CalleePtr, IntPtrTy); 5866 llvm::Value *Mask = llvm::ConstantInt::get(IntPtrTy, ~1); 5867 llvm::Value *AlignedCalleeAddress = 5868 Builder.CreateAnd(CalleeAddress, Mask); 5869 AlignedCalleePtr = 5870 Builder.CreateIntToPtr(AlignedCalleeAddress, CalleePtr->getType()); 5871 } else { 5872 AlignedCalleePtr = CalleePtr; 5873 } 5874 5875 llvm::Value *CalleePrefixStruct = AlignedCalleePtr; 5876 llvm::Value *CalleeSigPtr = 5877 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, -1, 0); 5878 llvm::Value *CalleeSig = 5879 Builder.CreateAlignedLoad(PrefixSigType, CalleeSigPtr, getIntAlign()); 5880 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig); 5881 5882 llvm::BasicBlock *Cont = createBasicBlock("cont"); 5883 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck"); 5884 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont); 5885 5886 EmitBlock(TypeCheck); 5887 llvm::Value *CalleeTypeHash = Builder.CreateAlignedLoad( 5888 Int32Ty, 5889 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, -1, 1), 5890 getPointerAlign()); 5891 llvm::Value *CalleeTypeHashMatch = 5892 Builder.CreateICmpEQ(CalleeTypeHash, TypeHash); 5893 llvm::Constant *StaticData[] = {EmitCheckSourceLocation(E->getBeginLoc()), 5894 EmitCheckTypeDescriptor(CalleeType)}; 5895 EmitCheck(std::make_pair(CalleeTypeHashMatch, SanitizerKind::Function), 5896 SanitizerHandler::FunctionTypeMismatch, StaticData, 5897 {CalleePtr}); 5898 5899 Builder.CreateBr(Cont); 5900 EmitBlock(Cont); 5901 } 5902 } 5903 5904 const auto *FnType = cast<FunctionType>(PointeeType); 5905 5906 // If we are checking indirect calls and this call is indirect, check that the 5907 // function pointer is a member of the bit set for the function type. 5908 if (SanOpts.has(SanitizerKind::CFIICall) && 5909 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) { 5910 SanitizerScope SanScope(this); 5911 EmitSanitizerStatReport(llvm::SanStat_CFI_ICall); 5912 5913 llvm::Metadata *MD; 5914 if (CGM.getCodeGenOpts().SanitizeCfiICallGeneralizePointers) 5915 MD = CGM.CreateMetadataIdentifierGeneralized(QualType(FnType, 0)); 5916 else 5917 MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0)); 5918 5919 llvm::Value *TypeId = llvm::MetadataAsValue::get(getLLVMContext(), MD); 5920 5921 llvm::Value *CalleePtr = Callee.getFunctionPointer(); 5922 llvm::Value *TypeTest = Builder.CreateCall( 5923 CGM.getIntrinsic(llvm::Intrinsic::type_test), {CalleePtr, TypeId}); 5924 5925 auto CrossDsoTypeId = CGM.CreateCrossDsoCfiTypeId(MD); 5926 llvm::Constant *StaticData[] = { 5927 llvm::ConstantInt::get(Int8Ty, CFITCK_ICall), 5928 EmitCheckSourceLocation(E->getBeginLoc()), 5929 EmitCheckTypeDescriptor(QualType(FnType, 0)), 5930 }; 5931 if (CGM.getCodeGenOpts().SanitizeCfiCrossDso && CrossDsoTypeId) { 5932 EmitCfiSlowPathCheck(SanitizerKind::CFIICall, TypeTest, CrossDsoTypeId, 5933 CalleePtr, StaticData); 5934 } else { 5935 EmitCheck(std::make_pair(TypeTest, SanitizerKind::CFIICall), 5936 SanitizerHandler::CFICheckFail, StaticData, 5937 {CalleePtr, llvm::UndefValue::get(IntPtrTy)}); 5938 } 5939 } 5940 5941 CallArgList Args; 5942 if (Chain) 5943 Args.add(RValue::get(Chain), CGM.getContext().VoidPtrTy); 5944 5945 // C++17 requires that we evaluate arguments to a call using assignment syntax 5946 // right-to-left, and that we evaluate arguments to certain other operators 5947 // left-to-right. Note that we allow this to override the order dictated by 5948 // the calling convention on the MS ABI, which means that parameter 5949 // destruction order is not necessarily reverse construction order. 5950 // FIXME: Revisit this based on C++ committee response to unimplementability. 5951 EvaluationOrder Order = EvaluationOrder::Default; 5952 bool StaticOperator = false; 5953 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(E)) { 5954 if (OCE->isAssignmentOp()) 5955 Order = EvaluationOrder::ForceRightToLeft; 5956 else { 5957 switch (OCE->getOperator()) { 5958 case OO_LessLess: 5959 case OO_GreaterGreater: 5960 case OO_AmpAmp: 5961 case OO_PipePipe: 5962 case OO_Comma: 5963 case OO_ArrowStar: 5964 Order = EvaluationOrder::ForceLeftToRight; 5965 break; 5966 default: 5967 break; 5968 } 5969 } 5970 5971 if (const auto *MD = 5972 dyn_cast_if_present<CXXMethodDecl>(OCE->getCalleeDecl()); 5973 MD && MD->isStatic()) 5974 StaticOperator = true; 5975 } 5976 5977 auto Arguments = E->arguments(); 5978 if (StaticOperator) { 5979 // If we're calling a static operator, we need to emit the object argument 5980 // and ignore it. 5981 EmitIgnoredExpr(E->getArg(0)); 5982 Arguments = drop_begin(Arguments, 1); 5983 } 5984 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), Arguments, 5985 E->getDirectCallee(), /*ParamsToSkip=*/0, Order); 5986 5987 const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeFreeFunctionCall( 5988 Args, FnType, /*ChainCall=*/Chain); 5989 5990 // C99 6.5.2.2p6: 5991 // If the expression that denotes the called function has a type 5992 // that does not include a prototype, [the default argument 5993 // promotions are performed]. If the number of arguments does not 5994 // equal the number of parameters, the behavior is undefined. If 5995 // the function is defined with a type that includes a prototype, 5996 // and either the prototype ends with an ellipsis (, ...) or the 5997 // types of the arguments after promotion are not compatible with 5998 // the types of the parameters, the behavior is undefined. If the 5999 // function is defined with a type that does not include a 6000 // prototype, and the types of the arguments after promotion are 6001 // not compatible with those of the parameters after promotion, 6002 // the behavior is undefined [except in some trivial cases]. 6003 // That is, in the general case, we should assume that a call 6004 // through an unprototyped function type works like a *non-variadic* 6005 // call. The way we make this work is to cast to the exact type 6006 // of the promoted arguments. 6007 // 6008 // Chain calls use this same code path to add the invisible chain parameter 6009 // to the function type. 6010 if (isa<FunctionNoProtoType>(FnType) || Chain) { 6011 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo); 6012 int AS = Callee.getFunctionPointer()->getType()->getPointerAddressSpace(); 6013 CalleeTy = CalleeTy->getPointerTo(AS); 6014 6015 llvm::Value *CalleePtr = Callee.getFunctionPointer(); 6016 CalleePtr = Builder.CreateBitCast(CalleePtr, CalleeTy, "callee.knr.cast"); 6017 Callee.setFunctionPointer(CalleePtr); 6018 } 6019 6020 // HIP function pointer contains kernel handle when it is used in triple 6021 // chevron. The kernel stub needs to be loaded from kernel handle and used 6022 // as callee. 6023 if (CGM.getLangOpts().HIP && !CGM.getLangOpts().CUDAIsDevice && 6024 isa<CUDAKernelCallExpr>(E) && 6025 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) { 6026 llvm::Value *Handle = Callee.getFunctionPointer(); 6027 auto *Stub = Builder.CreateLoad( 6028 Address(Handle, Handle->getType(), CGM.getPointerAlign())); 6029 Callee.setFunctionPointer(Stub); 6030 } 6031 llvm::CallBase *CallOrInvoke = nullptr; 6032 RValue Call = EmitCall(FnInfo, Callee, ReturnValue, Args, &CallOrInvoke, 6033 E == MustTailCall, E->getExprLoc()); 6034 6035 // Generate function declaration DISuprogram in order to be used 6036 // in debug info about call sites. 6037 if (CGDebugInfo *DI = getDebugInfo()) { 6038 if (auto *CalleeDecl = dyn_cast_or_null<FunctionDecl>(TargetDecl)) { 6039 FunctionArgList Args; 6040 QualType ResTy = BuildFunctionArgList(CalleeDecl, Args); 6041 DI->EmitFuncDeclForCallSite(CallOrInvoke, 6042 DI->getFunctionType(CalleeDecl, ResTy, Args), 6043 CalleeDecl); 6044 } 6045 } 6046 6047 return Call; 6048 } 6049 6050 LValue CodeGenFunction:: 6051 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) { 6052 Address BaseAddr = Address::invalid(); 6053 if (E->getOpcode() == BO_PtrMemI) { 6054 BaseAddr = EmitPointerWithAlignment(E->getLHS()); 6055 } else { 6056 BaseAddr = EmitLValue(E->getLHS()).getAddress(); 6057 } 6058 6059 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS()); 6060 const auto *MPT = E->getRHS()->getType()->castAs<MemberPointerType>(); 6061 6062 LValueBaseInfo BaseInfo; 6063 TBAAAccessInfo TBAAInfo; 6064 Address MemberAddr = 6065 EmitCXXMemberDataPointerAddress(E, BaseAddr, OffsetV, MPT, &BaseInfo, 6066 &TBAAInfo); 6067 6068 return MakeAddrLValue(MemberAddr, MPT->getPointeeType(), BaseInfo, TBAAInfo); 6069 } 6070 6071 /// Given the address of a temporary variable, produce an r-value of 6072 /// its type. 6073 RValue CodeGenFunction::convertTempToRValue(Address addr, 6074 QualType type, 6075 SourceLocation loc) { 6076 LValue lvalue = MakeAddrLValue(addr, type, AlignmentSource::Decl); 6077 switch (getEvaluationKind(type)) { 6078 case TEK_Complex: 6079 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc)); 6080 case TEK_Aggregate: 6081 return lvalue.asAggregateRValue(); 6082 case TEK_Scalar: 6083 return RValue::get(EmitLoadOfScalar(lvalue, loc)); 6084 } 6085 llvm_unreachable("bad evaluation kind"); 6086 } 6087 6088 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) { 6089 assert(Val->getType()->isFPOrFPVectorTy()); 6090 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val)) 6091 return; 6092 6093 llvm::MDBuilder MDHelper(getLLVMContext()); 6094 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy); 6095 6096 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node); 6097 } 6098 6099 void CodeGenFunction::SetSqrtFPAccuracy(llvm::Value *Val) { 6100 llvm::Type *EltTy = Val->getType()->getScalarType(); 6101 if (!EltTy->isFloatTy()) 6102 return; 6103 6104 if ((getLangOpts().OpenCL && 6105 !CGM.getCodeGenOpts().OpenCLCorrectlyRoundedDivSqrt) || 6106 (getLangOpts().HIP && getLangOpts().CUDAIsDevice && 6107 !CGM.getCodeGenOpts().HIPCorrectlyRoundedDivSqrt)) { 6108 // OpenCL v1.1 s7.4: minimum accuracy of single precision / is 3ulp 6109 // 6110 // OpenCL v1.2 s5.6.4.2: The -cl-fp32-correctly-rounded-divide-sqrt 6111 // build option allows an application to specify that single precision 6112 // floating-point divide (x/y and 1/x) and sqrt used in the program 6113 // source are correctly rounded. 6114 // 6115 // TODO: CUDA has a prec-sqrt flag 6116 SetFPAccuracy(Val, 3.0f); 6117 } 6118 } 6119 6120 void CodeGenFunction::SetDivFPAccuracy(llvm::Value *Val) { 6121 llvm::Type *EltTy = Val->getType()->getScalarType(); 6122 if (!EltTy->isFloatTy()) 6123 return; 6124 6125 if ((getLangOpts().OpenCL && 6126 !CGM.getCodeGenOpts().OpenCLCorrectlyRoundedDivSqrt) || 6127 (getLangOpts().HIP && getLangOpts().CUDAIsDevice && 6128 !CGM.getCodeGenOpts().HIPCorrectlyRoundedDivSqrt)) { 6129 // OpenCL v1.1 s7.4: minimum accuracy of single precision / is 2.5ulp 6130 // 6131 // OpenCL v1.2 s5.6.4.2: The -cl-fp32-correctly-rounded-divide-sqrt 6132 // build option allows an application to specify that single precision 6133 // floating-point divide (x/y and 1/x) and sqrt used in the program 6134 // source are correctly rounded. 6135 // 6136 // TODO: CUDA has a prec-div flag 6137 SetFPAccuracy(Val, 2.5f); 6138 } 6139 } 6140 6141 namespace { 6142 struct LValueOrRValue { 6143 LValue LV; 6144 RValue RV; 6145 }; 6146 } 6147 6148 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF, 6149 const PseudoObjectExpr *E, 6150 bool forLValue, 6151 AggValueSlot slot) { 6152 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques; 6153 6154 // Find the result expression, if any. 6155 const Expr *resultExpr = E->getResultExpr(); 6156 LValueOrRValue result; 6157 6158 for (PseudoObjectExpr::const_semantics_iterator 6159 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) { 6160 const Expr *semantic = *i; 6161 6162 // If this semantic expression is an opaque value, bind it 6163 // to the result of its source expression. 6164 if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) { 6165 // Skip unique OVEs. 6166 if (ov->isUnique()) { 6167 assert(ov != resultExpr && 6168 "A unique OVE cannot be used as the result expression"); 6169 continue; 6170 } 6171 6172 // If this is the result expression, we may need to evaluate 6173 // directly into the slot. 6174 typedef CodeGenFunction::OpaqueValueMappingData OVMA; 6175 OVMA opaqueData; 6176 if (ov == resultExpr && ov->isPRValue() && !forLValue && 6177 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) { 6178 CGF.EmitAggExpr(ov->getSourceExpr(), slot); 6179 LValue LV = CGF.MakeAddrLValue(slot.getAddress(), ov->getType(), 6180 AlignmentSource::Decl); 6181 opaqueData = OVMA::bind(CGF, ov, LV); 6182 result.RV = slot.asRValue(); 6183 6184 // Otherwise, emit as normal. 6185 } else { 6186 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr()); 6187 6188 // If this is the result, also evaluate the result now. 6189 if (ov == resultExpr) { 6190 if (forLValue) 6191 result.LV = CGF.EmitLValue(ov); 6192 else 6193 result.RV = CGF.EmitAnyExpr(ov, slot); 6194 } 6195 } 6196 6197 opaques.push_back(opaqueData); 6198 6199 // Otherwise, if the expression is the result, evaluate it 6200 // and remember the result. 6201 } else if (semantic == resultExpr) { 6202 if (forLValue) 6203 result.LV = CGF.EmitLValue(semantic); 6204 else 6205 result.RV = CGF.EmitAnyExpr(semantic, slot); 6206 6207 // Otherwise, evaluate the expression in an ignored context. 6208 } else { 6209 CGF.EmitIgnoredExpr(semantic); 6210 } 6211 } 6212 6213 // Unbind all the opaques now. 6214 for (unsigned i = 0, e = opaques.size(); i != e; ++i) 6215 opaques[i].unbind(CGF); 6216 6217 return result; 6218 } 6219 6220 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E, 6221 AggValueSlot slot) { 6222 return emitPseudoObjectExpr(*this, E, false, slot).RV; 6223 } 6224 6225 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) { 6226 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV; 6227 } 6228