1 //===--- CGExpr.cpp - Emit LLVM Code from Expressions ---------------------===//
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
7 //===----------------------------------------------------------------------===//
9 // This contains code to emit Expr nodes as LLVM code.
11 //===----------------------------------------------------------------------===//
15 #include "CGCleanup.h"
16 #include "CGDebugInfo.h"
17 #include "CGObjCRuntime.h"
18 #include "CGOpenMPRuntime.h"
19 #include "CGRecordLayout.h"
20 #include "CodeGenFunction.h"
21 #include "CodeGenModule.h"
22 #include "ConstantEmitter.h"
23 #include "TargetInfo.h"
24 #include "clang/AST/ASTContext.h"
25 #include "clang/AST/Attr.h"
26 #include "clang/AST/DeclObjC.h"
27 #include "clang/AST/NSAPI.h"
28 #include "clang/Basic/Builtins.h"
29 #include "clang/Basic/CodeGenOptions.h"
30 #include "clang/Basic/SourceManager.h"
31 #include "llvm/ADT/Hashing.h"
32 #include "llvm/ADT/StringExtras.h"
33 #include "llvm/IR/DataLayout.h"
34 #include "llvm/IR/Intrinsics.h"
35 #include "llvm/IR/LLVMContext.h"
36 #include "llvm/IR/MDBuilder.h"
37 #include "llvm/Support/ConvertUTF.h"
38 #include "llvm/Support/MathExtras.h"
39 #include "llvm/Support/Path.h"
40 #include "llvm/Transforms/Utils/SanitizerStats.h"
44 using namespace clang;
45 using namespace CodeGen;
47 //===--------------------------------------------------------------------===//
48 // Miscellaneous Helper Methods
49 //===--------------------------------------------------------------------===//
51 llvm::Value *CodeGenFunction::EmitCastToVoidPtr(llvm::Value *value) {
52 unsigned addressSpace =
53 cast<llvm::PointerType>(value->getType())->getAddressSpace();
55 llvm::PointerType *destType = Int8PtrTy;
57 destType = llvm::Type::getInt8PtrTy(getLLVMContext(), addressSpace);
59 if (value->getType() == destType) return value;
60 return Builder.CreateBitCast(value, destType);
63 /// CreateTempAlloca - This creates a alloca and inserts it into the entry
65 Address CodeGenFunction::CreateTempAllocaWithoutCast(llvm::Type *Ty,
68 llvm::Value *ArraySize) {
69 auto Alloca = CreateTempAlloca(Ty, Name, ArraySize);
70 Alloca->setAlignment(Align.getAsAlign());
71 return Address(Alloca, Align);
74 /// CreateTempAlloca - This creates a alloca and inserts it into the entry
75 /// block. The alloca is casted to default address space if necessary.
76 Address CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, CharUnits Align,
78 llvm::Value *ArraySize,
79 Address *AllocaAddr) {
80 auto Alloca = CreateTempAllocaWithoutCast(Ty, Align, Name, ArraySize);
83 llvm::Value *V = Alloca.getPointer();
84 // Alloca always returns a pointer in alloca address space, which may
85 // be different from the type defined by the language. For example,
86 // in C++ the auto variables are in the default address space. Therefore
87 // cast alloca to the default address space when necessary.
88 if (getASTAllocaAddressSpace() != LangAS::Default) {
89 auto DestAddrSpace = getContext().getTargetAddressSpace(LangAS::Default);
90 llvm::IRBuilderBase::InsertPointGuard IPG(Builder);
91 // When ArraySize is nullptr, alloca is inserted at AllocaInsertPt,
92 // otherwise alloca is inserted at the current insertion point of the
95 Builder.SetInsertPoint(AllocaInsertPt);
96 V = getTargetHooks().performAddrSpaceCast(
97 *this, V, getASTAllocaAddressSpace(), LangAS::Default,
98 Ty->getPointerTo(DestAddrSpace), /*non-null*/ true);
101 return Address(V, Align);
104 /// CreateTempAlloca - This creates an alloca and inserts it into the entry
105 /// block if \p ArraySize is nullptr, otherwise inserts it at the current
106 /// insertion point of the builder.
107 llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty,
109 llvm::Value *ArraySize) {
111 return Builder.CreateAlloca(Ty, ArraySize, Name);
112 return new llvm::AllocaInst(Ty, CGM.getDataLayout().getAllocaAddrSpace(),
113 ArraySize, Name, AllocaInsertPt);
116 /// CreateDefaultAlignTempAlloca - This creates an alloca with the
117 /// default alignment of the corresponding LLVM type, which is *not*
118 /// guaranteed to be related in any way to the expected alignment of
119 /// an AST type that might have been lowered to Ty.
120 Address CodeGenFunction::CreateDefaultAlignTempAlloca(llvm::Type *Ty,
123 CharUnits::fromQuantity(CGM.getDataLayout().getABITypeAlignment(Ty));
124 return CreateTempAlloca(Ty, Align, Name);
127 void CodeGenFunction::InitTempAlloca(Address Var, llvm::Value *Init) {
128 assert(isa<llvm::AllocaInst>(Var.getPointer()));
129 auto *Store = new llvm::StoreInst(Init, Var.getPointer(), /*volatile*/ false,
130 Var.getAlignment().getAsAlign());
131 llvm::BasicBlock *Block = AllocaInsertPt->getParent();
132 Block->getInstList().insertAfter(AllocaInsertPt->getIterator(), Store);
135 Address CodeGenFunction::CreateIRTemp(QualType Ty, const Twine &Name) {
136 CharUnits Align = getContext().getTypeAlignInChars(Ty);
137 return CreateTempAlloca(ConvertType(Ty), Align, Name);
140 Address CodeGenFunction::CreateMemTemp(QualType Ty, const Twine &Name,
142 // FIXME: Should we prefer the preferred type alignment here?
143 return CreateMemTemp(Ty, getContext().getTypeAlignInChars(Ty), Name, Alloca);
146 Address CodeGenFunction::CreateMemTemp(QualType Ty, CharUnits Align,
147 const Twine &Name, Address *Alloca) {
148 Address Result = CreateTempAlloca(ConvertTypeForMem(Ty), Align, Name,
149 /*ArraySize=*/nullptr, Alloca);
151 if (Ty->isConstantMatrixType()) {
152 auto *ArrayTy = cast<llvm::ArrayType>(Result.getType()->getElementType());
153 auto *VectorTy = llvm::FixedVectorType::get(ArrayTy->getElementType(),
154 ArrayTy->getNumElements());
157 Builder.CreateBitCast(Result.getPointer(), VectorTy->getPointerTo()),
158 Result.getAlignment());
163 Address CodeGenFunction::CreateMemTempWithoutCast(QualType Ty, CharUnits Align,
165 return CreateTempAllocaWithoutCast(ConvertTypeForMem(Ty), Align, Name);
168 Address CodeGenFunction::CreateMemTempWithoutCast(QualType Ty,
170 return CreateMemTempWithoutCast(Ty, getContext().getTypeAlignInChars(Ty),
174 /// EvaluateExprAsBool - Perform the usual unary conversions on the specified
175 /// expression and compare the result against zero, returning an Int1Ty value.
176 llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
177 PGO.setCurrentStmt(E);
178 if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) {
179 llvm::Value *MemPtr = EmitScalarExpr(E);
180 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT);
183 QualType BoolTy = getContext().BoolTy;
184 SourceLocation Loc = E->getExprLoc();
185 if (!E->getType()->isAnyComplexType())
186 return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy, Loc);
188 return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(), BoolTy,
192 /// EmitIgnoredExpr - Emit code to compute the specified expression,
193 /// ignoring the result.
194 void CodeGenFunction::EmitIgnoredExpr(const Expr *E) {
196 return (void) EmitAnyExpr(E, AggValueSlot::ignored(), true);
198 // Just emit it as an l-value and drop the result.
202 /// EmitAnyExpr - Emit code to compute the specified expression which
203 /// can have any type. The result is returned as an RValue struct.
204 /// If this is an aggregate expression, AggSlot indicates where the
205 /// result should be returned.
206 RValue CodeGenFunction::EmitAnyExpr(const Expr *E,
207 AggValueSlot aggSlot,
209 switch (getEvaluationKind(E->getType())) {
211 return RValue::get(EmitScalarExpr(E, ignoreResult));
213 return RValue::getComplex(EmitComplexExpr(E, ignoreResult, ignoreResult));
215 if (!ignoreResult && aggSlot.isIgnored())
216 aggSlot = CreateAggTemp(E->getType(), "agg-temp");
217 EmitAggExpr(E, aggSlot);
218 return aggSlot.asRValue();
220 llvm_unreachable("bad evaluation kind");
223 /// EmitAnyExprToTemp - Similar to EmitAnyExpr(), however, the result will
224 /// always be accessible even if no aggregate location is provided.
225 RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) {
226 AggValueSlot AggSlot = AggValueSlot::ignored();
228 if (hasAggregateEvaluationKind(E->getType()))
229 AggSlot = CreateAggTemp(E->getType(), "agg.tmp");
230 return EmitAnyExpr(E, AggSlot);
233 /// EmitAnyExprToMem - Evaluate an expression into a given memory
235 void CodeGenFunction::EmitAnyExprToMem(const Expr *E,
239 // FIXME: This function should take an LValue as an argument.
240 switch (getEvaluationKind(E->getType())) {
242 EmitComplexExprIntoLValue(E, MakeAddrLValue(Location, E->getType()),
246 case TEK_Aggregate: {
247 EmitAggExpr(E, AggValueSlot::forAddr(Location, Quals,
248 AggValueSlot::IsDestructed_t(IsInit),
249 AggValueSlot::DoesNotNeedGCBarriers,
250 AggValueSlot::IsAliased_t(!IsInit),
251 AggValueSlot::MayOverlap));
256 RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false));
257 LValue LV = MakeAddrLValue(Location, E->getType());
258 EmitStoreThroughLValue(RV, LV);
262 llvm_unreachable("bad evaluation kind");
266 pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M,
267 const Expr *E, Address ReferenceTemporary) {
268 // Objective-C++ ARC:
269 // If we are binding a reference to a temporary that has ownership, we
270 // need to perform retain/release operations on the temporary.
272 // FIXME: This should be looking at E, not M.
273 if (auto Lifetime = M->getType().getObjCLifetime()) {
275 case Qualifiers::OCL_None:
276 case Qualifiers::OCL_ExplicitNone:
277 // Carry on to normal cleanup handling.
280 case Qualifiers::OCL_Autoreleasing:
281 // Nothing to do; cleaned up by an autorelease pool.
284 case Qualifiers::OCL_Strong:
285 case Qualifiers::OCL_Weak:
286 switch (StorageDuration Duration = M->getStorageDuration()) {
288 // Note: we intentionally do not register a cleanup to release
289 // the object on program termination.
293 // FIXME: We should probably register a cleanup in this case.
297 case SD_FullExpression:
298 CodeGenFunction::Destroyer *Destroy;
299 CleanupKind CleanupKind;
300 if (Lifetime == Qualifiers::OCL_Strong) {
301 const ValueDecl *VD = M->getExtendingDecl();
303 VD && isa<VarDecl>(VD) && VD->hasAttr<ObjCPreciseLifetimeAttr>();
304 CleanupKind = CGF.getARCCleanupKind();
305 Destroy = Precise ? &CodeGenFunction::destroyARCStrongPrecise
306 : &CodeGenFunction::destroyARCStrongImprecise;
308 // __weak objects always get EH cleanups; otherwise, exceptions
309 // could cause really nasty crashes instead of mere leaks.
310 CleanupKind = NormalAndEHCleanup;
311 Destroy = &CodeGenFunction::destroyARCWeak;
313 if (Duration == SD_FullExpression)
314 CGF.pushDestroy(CleanupKind, ReferenceTemporary,
315 M->getType(), *Destroy,
316 CleanupKind & EHCleanup);
318 CGF.pushLifetimeExtendedDestroy(CleanupKind, ReferenceTemporary,
320 *Destroy, CleanupKind & EHCleanup);
324 llvm_unreachable("temporary cannot have dynamic storage duration");
326 llvm_unreachable("unknown storage duration");
330 CXXDestructorDecl *ReferenceTemporaryDtor = nullptr;
331 if (const RecordType *RT =
332 E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
333 // Get the destructor for the reference temporary.
334 auto *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
335 if (!ClassDecl->hasTrivialDestructor())
336 ReferenceTemporaryDtor = ClassDecl->getDestructor();
339 if (!ReferenceTemporaryDtor)
342 // Call the destructor for the temporary.
343 switch (M->getStorageDuration()) {
346 llvm::FunctionCallee CleanupFn;
347 llvm::Constant *CleanupArg;
348 if (E->getType()->isArrayType()) {
349 CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper(
350 ReferenceTemporary, E->getType(),
351 CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions,
352 dyn_cast_or_null<VarDecl>(M->getExtendingDecl()));
353 CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy);
355 CleanupFn = CGF.CGM.getAddrAndTypeOfCXXStructor(
356 GlobalDecl(ReferenceTemporaryDtor, Dtor_Complete));
357 CleanupArg = cast<llvm::Constant>(ReferenceTemporary.getPointer());
359 CGF.CGM.getCXXABI().registerGlobalDtor(
360 CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg);
364 case SD_FullExpression:
365 CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(),
366 CodeGenFunction::destroyCXXObject,
367 CGF.getLangOpts().Exceptions);
371 CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup,
372 ReferenceTemporary, E->getType(),
373 CodeGenFunction::destroyCXXObject,
374 CGF.getLangOpts().Exceptions);
378 llvm_unreachable("temporary cannot have dynamic storage duration");
382 static Address createReferenceTemporary(CodeGenFunction &CGF,
383 const MaterializeTemporaryExpr *M,
385 Address *Alloca = nullptr) {
386 auto &TCG = CGF.getTargetHooks();
387 switch (M->getStorageDuration()) {
388 case SD_FullExpression:
390 // If we have a constant temporary array or record try to promote it into a
391 // constant global under the same rules a normal constant would've been
392 // promoted. This is easier on the optimizer and generally emits fewer
394 QualType Ty = Inner->getType();
395 if (CGF.CGM.getCodeGenOpts().MergeAllConstants &&
396 (Ty->isArrayType() || Ty->isRecordType()) &&
397 CGF.CGM.isTypeConstant(Ty, true))
398 if (auto Init = ConstantEmitter(CGF).tryEmitAbstract(Inner, Ty)) {
399 if (auto AddrSpace = CGF.getTarget().getConstantAddressSpace()) {
400 auto AS = AddrSpace.getValue();
401 auto *GV = new llvm::GlobalVariable(
402 CGF.CGM.getModule(), Init->getType(), /*isConstant=*/true,
403 llvm::GlobalValue::PrivateLinkage, Init, ".ref.tmp", nullptr,
404 llvm::GlobalValue::NotThreadLocal,
405 CGF.getContext().getTargetAddressSpace(AS));
406 CharUnits alignment = CGF.getContext().getTypeAlignInChars(Ty);
407 GV->setAlignment(alignment.getAsAlign());
408 llvm::Constant *C = GV;
409 if (AS != LangAS::Default)
410 C = TCG.performAddrSpaceCast(
411 CGF.CGM, GV, AS, LangAS::Default,
412 GV->getValueType()->getPointerTo(
413 CGF.getContext().getTargetAddressSpace(LangAS::Default)));
414 // FIXME: Should we put the new global into a COMDAT?
415 return Address(C, alignment);
418 return CGF.CreateMemTemp(Ty, "ref.tmp", Alloca);
422 return CGF.CGM.GetAddrOfGlobalTemporary(M, Inner);
425 llvm_unreachable("temporary can't have dynamic storage duration");
427 llvm_unreachable("unknown storage duration");
430 /// Helper method to check if the underlying ABI is AAPCS
431 static bool isAAPCS(const TargetInfo &TargetInfo) {
432 return TargetInfo.getABI().startswith("aapcs");
435 LValue CodeGenFunction::
436 EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) {
437 const Expr *E = M->getSubExpr();
439 assert((!M->getExtendingDecl() || !isa<VarDecl>(M->getExtendingDecl()) ||
440 !cast<VarDecl>(M->getExtendingDecl())->isARCPseudoStrong()) &&
441 "Reference should never be pseudo-strong!");
443 // FIXME: ideally this would use EmitAnyExprToMem, however, we cannot do so
444 // as that will cause the lifetime adjustment to be lost for ARC
445 auto ownership = M->getType().getObjCLifetime();
446 if (ownership != Qualifiers::OCL_None &&
447 ownership != Qualifiers::OCL_ExplicitNone) {
448 Address Object = createReferenceTemporary(*this, M, E);
449 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) {
450 Object = Address(llvm::ConstantExpr::getBitCast(Var,
451 ConvertTypeForMem(E->getType())
452 ->getPointerTo(Object.getAddressSpace())),
453 Object.getAlignment());
455 // createReferenceTemporary will promote the temporary to a global with a
456 // constant initializer if it can. It can only do this to a value of
457 // ARC-manageable type if the value is global and therefore "immune" to
458 // ref-counting operations. Therefore we have no need to emit either a
459 // dynamic initialization or a cleanup and we can just return the address
461 if (Var->hasInitializer())
462 return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl);
464 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
466 LValue RefTempDst = MakeAddrLValue(Object, M->getType(),
467 AlignmentSource::Decl);
469 switch (getEvaluationKind(E->getType())) {
470 default: llvm_unreachable("expected scalar or aggregate expression");
472 EmitScalarInit(E, M->getExtendingDecl(), RefTempDst, false);
474 case TEK_Aggregate: {
475 EmitAggExpr(E, AggValueSlot::forAddr(Object,
476 E->getType().getQualifiers(),
477 AggValueSlot::IsDestructed,
478 AggValueSlot::DoesNotNeedGCBarriers,
479 AggValueSlot::IsNotAliased,
480 AggValueSlot::DoesNotOverlap));
485 pushTemporaryCleanup(*this, M, E, Object);
489 SmallVector<const Expr *, 2> CommaLHSs;
490 SmallVector<SubobjectAdjustment, 2> Adjustments;
491 E = E->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
493 for (const auto &Ignored : CommaLHSs)
494 EmitIgnoredExpr(Ignored);
496 if (const auto *opaque = dyn_cast<OpaqueValueExpr>(E)) {
497 if (opaque->getType()->isRecordType()) {
498 assert(Adjustments.empty());
499 return EmitOpaqueValueLValue(opaque);
503 // Create and initialize the reference temporary.
504 Address Alloca = Address::invalid();
505 Address Object = createReferenceTemporary(*this, M, E, &Alloca);
506 if (auto *Var = dyn_cast<llvm::GlobalVariable>(
507 Object.getPointer()->stripPointerCasts())) {
508 Object = Address(llvm::ConstantExpr::getBitCast(
509 cast<llvm::Constant>(Object.getPointer()),
510 ConvertTypeForMem(E->getType())->getPointerTo()),
511 Object.getAlignment());
512 // If the temporary is a global and has a constant initializer or is a
513 // constant temporary that we promoted to a global, we may have already
515 if (!Var->hasInitializer()) {
516 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
517 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
520 switch (M->getStorageDuration()) {
522 if (auto *Size = EmitLifetimeStart(
523 CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()),
524 Alloca.getPointer())) {
525 pushCleanupAfterFullExpr<CallLifetimeEnd>(NormalEHLifetimeMarker,
530 case SD_FullExpression: {
531 if (!ShouldEmitLifetimeMarkers)
534 // Avoid creating a conditional cleanup just to hold an llvm.lifetime.end
535 // marker. Instead, start the lifetime of a conditional temporary earlier
536 // so that it's unconditional. Don't do this with sanitizers which need
537 // more precise lifetime marks.
538 ConditionalEvaluation *OldConditional = nullptr;
539 CGBuilderTy::InsertPoint OldIP;
540 if (isInConditionalBranch() && !E->getType().isDestructedType() &&
541 !SanOpts.has(SanitizerKind::HWAddress) &&
542 !SanOpts.has(SanitizerKind::Memory) &&
543 !CGM.getCodeGenOpts().SanitizeAddressUseAfterScope) {
544 OldConditional = OutermostConditional;
545 OutermostConditional = nullptr;
547 OldIP = Builder.saveIP();
548 llvm::BasicBlock *Block = OldConditional->getStartingBlock();
549 Builder.restoreIP(CGBuilderTy::InsertPoint(
550 Block, llvm::BasicBlock::iterator(Block->back())));
553 if (auto *Size = EmitLifetimeStart(
554 CGM.getDataLayout().getTypeAllocSize(Alloca.getElementType()),
555 Alloca.getPointer())) {
556 pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Alloca,
560 if (OldConditional) {
561 OutermostConditional = OldConditional;
562 Builder.restoreIP(OldIP);
570 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
572 pushTemporaryCleanup(*this, M, E, Object);
574 // Perform derived-to-base casts and/or field accesses, to get from the
575 // temporary object we created (and, potentially, for which we extended
576 // the lifetime) to the subobject we're binding the reference to.
577 for (unsigned I = Adjustments.size(); I != 0; --I) {
578 SubobjectAdjustment &Adjustment = Adjustments[I-1];
579 switch (Adjustment.Kind) {
580 case SubobjectAdjustment::DerivedToBaseAdjustment:
582 GetAddressOfBaseClass(Object, Adjustment.DerivedToBase.DerivedClass,
583 Adjustment.DerivedToBase.BasePath->path_begin(),
584 Adjustment.DerivedToBase.BasePath->path_end(),
585 /*NullCheckValue=*/ false, E->getExprLoc());
588 case SubobjectAdjustment::FieldAdjustment: {
589 LValue LV = MakeAddrLValue(Object, E->getType(), AlignmentSource::Decl);
590 LV = EmitLValueForField(LV, Adjustment.Field);
591 assert(LV.isSimple() &&
592 "materialized temporary field is not a simple lvalue");
593 Object = LV.getAddress(*this);
597 case SubobjectAdjustment::MemberPointerAdjustment: {
598 llvm::Value *Ptr = EmitScalarExpr(Adjustment.Ptr.RHS);
599 Object = EmitCXXMemberDataPointerAddress(E, Object, Ptr,
606 return MakeAddrLValue(Object, M->getType(), AlignmentSource::Decl);
610 CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E) {
611 // Emit the expression as an lvalue.
612 LValue LV = EmitLValue(E);
613 assert(LV.isSimple());
614 llvm::Value *Value = LV.getPointer(*this);
616 if (sanitizePerformTypeCheck() && !E->getType()->isFunctionType()) {
617 // C++11 [dcl.ref]p5 (as amended by core issue 453):
618 // If a glvalue to which a reference is directly bound designates neither
619 // an existing object or function of an appropriate type nor a region of
620 // storage of suitable size and alignment to contain an object of the
621 // reference's type, the behavior is undefined.
622 QualType Ty = E->getType();
623 EmitTypeCheck(TCK_ReferenceBinding, E->getExprLoc(), Value, Ty);
626 return RValue::get(Value);
630 /// getAccessedFieldNo - Given an encoded value and a result number, return the
631 /// input field number being accessed.
632 unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
633 const llvm::Constant *Elts) {
634 return cast<llvm::ConstantInt>(Elts->getAggregateElement(Idx))
638 /// Emit the hash_16_bytes function from include/llvm/ADT/Hashing.h.
639 static llvm::Value *emitHash16Bytes(CGBuilderTy &Builder, llvm::Value *Low,
641 llvm::Value *KMul = Builder.getInt64(0x9ddfea08eb382d69ULL);
642 llvm::Value *K47 = Builder.getInt64(47);
643 llvm::Value *A0 = Builder.CreateMul(Builder.CreateXor(Low, High), KMul);
644 llvm::Value *A1 = Builder.CreateXor(Builder.CreateLShr(A0, K47), A0);
645 llvm::Value *B0 = Builder.CreateMul(Builder.CreateXor(High, A1), KMul);
646 llvm::Value *B1 = Builder.CreateXor(Builder.CreateLShr(B0, K47), B0);
647 return Builder.CreateMul(B1, KMul);
650 bool CodeGenFunction::isNullPointerAllowed(TypeCheckKind TCK) {
651 return TCK == TCK_DowncastPointer || TCK == TCK_Upcast ||
652 TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation;
655 bool CodeGenFunction::isVptrCheckRequired(TypeCheckKind TCK, QualType Ty) {
656 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
657 return (RD && RD->hasDefinition() && RD->isDynamicClass()) &&
658 (TCK == TCK_MemberAccess || TCK == TCK_MemberCall ||
659 TCK == TCK_DowncastPointer || TCK == TCK_DowncastReference ||
660 TCK == TCK_UpcastToVirtualBase || TCK == TCK_DynamicOperation);
663 bool CodeGenFunction::sanitizePerformTypeCheck() const {
664 return SanOpts.has(SanitizerKind::Null) |
665 SanOpts.has(SanitizerKind::Alignment) |
666 SanOpts.has(SanitizerKind::ObjectSize) |
667 SanOpts.has(SanitizerKind::Vptr);
670 void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc,
671 llvm::Value *Ptr, QualType Ty,
673 SanitizerSet SkippedChecks,
674 llvm::Value *ArraySize) {
675 if (!sanitizePerformTypeCheck())
678 // Don't check pointers outside the default address space. The null check
679 // isn't correct, the object-size check isn't supported by LLVM, and we can't
680 // communicate the addresses to the runtime handler for the vptr check.
681 if (Ptr->getType()->getPointerAddressSpace())
684 // Don't check pointers to volatile data. The behavior here is implementation-
686 if (Ty.isVolatileQualified())
689 SanitizerScope SanScope(this);
691 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 3> Checks;
692 llvm::BasicBlock *Done = nullptr;
694 // Quickly determine whether we have a pointer to an alloca. It's possible
695 // to skip null checks, and some alignment checks, for these pointers. This
696 // can reduce compile-time significantly.
697 auto PtrToAlloca = dyn_cast<llvm::AllocaInst>(Ptr->stripPointerCasts());
699 llvm::Value *True = llvm::ConstantInt::getTrue(getLLVMContext());
700 llvm::Value *IsNonNull = nullptr;
701 bool IsGuaranteedNonNull =
702 SkippedChecks.has(SanitizerKind::Null) || PtrToAlloca;
703 bool AllowNullPointers = isNullPointerAllowed(TCK);
704 if ((SanOpts.has(SanitizerKind::Null) || AllowNullPointers) &&
705 !IsGuaranteedNonNull) {
706 // The glvalue must not be an empty glvalue.
707 IsNonNull = Builder.CreateIsNotNull(Ptr);
709 // The IR builder can constant-fold the null check if the pointer points to
711 IsGuaranteedNonNull = IsNonNull == True;
713 // Skip the null check if the pointer is known to be non-null.
714 if (!IsGuaranteedNonNull) {
715 if (AllowNullPointers) {
716 // When performing pointer casts, it's OK if the value is null.
717 // Skip the remaining checks in that case.
718 Done = createBasicBlock("null");
719 llvm::BasicBlock *Rest = createBasicBlock("not.null");
720 Builder.CreateCondBr(IsNonNull, Rest, Done);
723 Checks.push_back(std::make_pair(IsNonNull, SanitizerKind::Null));
728 if (SanOpts.has(SanitizerKind::ObjectSize) &&
729 !SkippedChecks.has(SanitizerKind::ObjectSize) &&
730 !Ty->isIncompleteType()) {
731 uint64_t TySize = CGM.getMinimumObjectSize(Ty).getQuantity();
732 llvm::Value *Size = llvm::ConstantInt::get(IntPtrTy, TySize);
734 Size = Builder.CreateMul(Size, ArraySize);
736 // Degenerate case: new X[0] does not need an objectsize check.
737 llvm::Constant *ConstantSize = dyn_cast<llvm::Constant>(Size);
738 if (!ConstantSize || !ConstantSize->isNullValue()) {
739 // The glvalue must refer to a large enough storage region.
740 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation
742 // FIXME: Get object address space
743 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy };
744 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys);
745 llvm::Value *Min = Builder.getFalse();
746 llvm::Value *NullIsUnknown = Builder.getFalse();
747 llvm::Value *Dynamic = Builder.getFalse();
748 llvm::Value *CastAddr = Builder.CreateBitCast(Ptr, Int8PtrTy);
749 llvm::Value *LargeEnough = Builder.CreateICmpUGE(
750 Builder.CreateCall(F, {CastAddr, Min, NullIsUnknown, Dynamic}), Size);
751 Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize));
755 uint64_t AlignVal = 0;
756 llvm::Value *PtrAsInt = nullptr;
758 if (SanOpts.has(SanitizerKind::Alignment) &&
759 !SkippedChecks.has(SanitizerKind::Alignment)) {
760 AlignVal = Alignment.getQuantity();
761 if (!Ty->isIncompleteType() && !AlignVal)
762 AlignVal = CGM.getNaturalTypeAlignment(Ty, nullptr, nullptr,
763 /*ForPointeeType=*/true)
766 // The glvalue must be suitably aligned.
768 (!PtrToAlloca || PtrToAlloca->getAlignment() < AlignVal)) {
769 PtrAsInt = Builder.CreatePtrToInt(Ptr, IntPtrTy);
770 llvm::Value *Align = Builder.CreateAnd(
771 PtrAsInt, llvm::ConstantInt::get(IntPtrTy, AlignVal - 1));
772 llvm::Value *Aligned =
773 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0));
775 Checks.push_back(std::make_pair(Aligned, SanitizerKind::Alignment));
779 if (Checks.size() > 0) {
780 // Make sure we're not losing information. Alignment needs to be a power of
782 assert(!AlignVal || (uint64_t)1 << llvm::Log2_64(AlignVal) == AlignVal);
783 llvm::Constant *StaticData[] = {
784 EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(Ty),
785 llvm::ConstantInt::get(Int8Ty, AlignVal ? llvm::Log2_64(AlignVal) : 1),
786 llvm::ConstantInt::get(Int8Ty, TCK)};
787 EmitCheck(Checks, SanitizerHandler::TypeMismatch, StaticData,
788 PtrAsInt ? PtrAsInt : Ptr);
791 // If possible, check that the vptr indicates that there is a subobject of
792 // type Ty at offset zero within this object.
794 // C++11 [basic.life]p5,6:
795 // [For storage which does not refer to an object within its lifetime]
796 // The program has undefined behavior if:
797 // -- the [pointer or glvalue] is used to access a non-static data member
798 // or call a non-static member function
799 if (SanOpts.has(SanitizerKind::Vptr) &&
800 !SkippedChecks.has(SanitizerKind::Vptr) && isVptrCheckRequired(TCK, Ty)) {
801 // Ensure that the pointer is non-null before loading it. If there is no
802 // compile-time guarantee, reuse the run-time null check or emit a new one.
803 if (!IsGuaranteedNonNull) {
805 IsNonNull = Builder.CreateIsNotNull(Ptr);
807 Done = createBasicBlock("vptr.null");
808 llvm::BasicBlock *VptrNotNull = createBasicBlock("vptr.not.null");
809 Builder.CreateCondBr(IsNonNull, VptrNotNull, Done);
810 EmitBlock(VptrNotNull);
813 // Compute a hash of the mangled name of the type.
815 // FIXME: This is not guaranteed to be deterministic! Move to a
816 // fingerprinting mechanism once LLVM provides one. For the time
817 // being the implementation happens to be deterministic.
818 SmallString<64> MangledName;
819 llvm::raw_svector_ostream Out(MangledName);
820 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(),
823 // Blacklist based on the mangled type.
824 if (!CGM.getContext().getSanitizerBlacklist().isBlacklistedType(
825 SanitizerKind::Vptr, Out.str())) {
826 llvm::hash_code TypeHash = hash_value(Out.str());
828 // Load the vptr, and compute hash_16_bytes(TypeHash, vptr).
829 llvm::Value *Low = llvm::ConstantInt::get(Int64Ty, TypeHash);
830 llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0);
831 Address VPtrAddr(Builder.CreateBitCast(Ptr, VPtrTy), getPointerAlign());
832 llvm::Value *VPtrVal = Builder.CreateLoad(VPtrAddr);
833 llvm::Value *High = Builder.CreateZExt(VPtrVal, Int64Ty);
835 llvm::Value *Hash = emitHash16Bytes(Builder, Low, High);
836 Hash = Builder.CreateTrunc(Hash, IntPtrTy);
838 // Look the hash up in our cache.
839 const int CacheSize = 128;
840 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize);
841 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable,
842 "__ubsan_vptr_type_cache");
843 llvm::Value *Slot = Builder.CreateAnd(Hash,
844 llvm::ConstantInt::get(IntPtrTy,
846 llvm::Value *Indices[] = { Builder.getInt32(0), Slot };
847 llvm::Value *CacheVal =
848 Builder.CreateAlignedLoad(Builder.CreateInBoundsGEP(Cache, Indices),
851 // If the hash isn't in the cache, call a runtime handler to perform the
852 // hard work of checking whether the vptr is for an object of the right
853 // type. This will either fill in the cache and return, or produce a
855 llvm::Value *EqualHash = Builder.CreateICmpEQ(CacheVal, Hash);
856 llvm::Constant *StaticData[] = {
857 EmitCheckSourceLocation(Loc),
858 EmitCheckTypeDescriptor(Ty),
859 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()),
860 llvm::ConstantInt::get(Int8Ty, TCK)
862 llvm::Value *DynamicData[] = { Ptr, Hash };
863 EmitCheck(std::make_pair(EqualHash, SanitizerKind::Vptr),
864 SanitizerHandler::DynamicTypeCacheMiss, StaticData,
870 Builder.CreateBr(Done);
875 /// Determine whether this expression refers to a flexible array member in a
876 /// struct. We disable array bounds checks for such members.
877 static bool isFlexibleArrayMemberExpr(const Expr *E) {
878 // For compatibility with existing code, we treat arrays of length 0 or
879 // 1 as flexible array members.
880 // FIXME: This is inconsistent with the warning code in SemaChecking. Unify
881 // the two mechanisms.
882 const ArrayType *AT = E->getType()->castAsArrayTypeUnsafe();
883 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT)) {
884 // FIXME: Sema doesn't treat [1] as a flexible array member if the bound
885 // was produced by macro expansion.
886 if (CAT->getSize().ugt(1))
888 } else if (!isa<IncompleteArrayType>(AT))
891 E = E->IgnoreParens();
893 // A flexible array member must be the last member in the class.
894 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
895 // FIXME: If the base type of the member expr is not FD->getParent(),
896 // this should not be treated as a flexible array member access.
897 if (const auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
898 // FIXME: Sema doesn't treat a T[1] union member as a flexible array
899 // member, only a T[0] or T[] member gets that treatment.
900 if (FD->getParent()->isUnion())
902 RecordDecl::field_iterator FI(
903 DeclContext::decl_iterator(const_cast<FieldDecl *>(FD)));
904 return ++FI == FD->getParent()->field_end();
906 } else if (const auto *IRE = dyn_cast<ObjCIvarRefExpr>(E)) {
907 return IRE->getDecl()->getNextIvar() == nullptr;
913 llvm::Value *CodeGenFunction::LoadPassedObjectSize(const Expr *E,
915 ASTContext &C = getContext();
916 uint64_t EltSize = C.getTypeSizeInChars(EltTy).getQuantity();
920 auto *ArrayDeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts());
924 auto *ParamDecl = dyn_cast<ParmVarDecl>(ArrayDeclRef->getDecl());
928 auto *POSAttr = ParamDecl->getAttr<PassObjectSizeAttr>();
932 // Don't load the size if it's a lower bound.
933 int POSType = POSAttr->getType();
934 if (POSType != 0 && POSType != 1)
937 // Find the implicit size parameter.
938 auto PassedSizeIt = SizeArguments.find(ParamDecl);
939 if (PassedSizeIt == SizeArguments.end())
942 const ImplicitParamDecl *PassedSizeDecl = PassedSizeIt->second;
943 assert(LocalDeclMap.count(PassedSizeDecl) && "Passed size not loadable");
944 Address AddrOfSize = LocalDeclMap.find(PassedSizeDecl)->second;
945 llvm::Value *SizeInBytes = EmitLoadOfScalar(AddrOfSize, /*Volatile=*/false,
946 C.getSizeType(), E->getExprLoc());
947 llvm::Value *SizeOfElement =
948 llvm::ConstantInt::get(SizeInBytes->getType(), EltSize);
949 return Builder.CreateUDiv(SizeInBytes, SizeOfElement);
952 /// If Base is known to point to the start of an array, return the length of
953 /// that array. Return 0 if the length cannot be determined.
954 static llvm::Value *getArrayIndexingBound(
955 CodeGenFunction &CGF, const Expr *Base, QualType &IndexedType) {
956 // For the vector indexing extension, the bound is the number of elements.
957 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) {
958 IndexedType = Base->getType();
959 return CGF.Builder.getInt32(VT->getNumElements());
962 Base = Base->IgnoreParens();
964 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
965 if (CE->getCastKind() == CK_ArrayToPointerDecay &&
966 !isFlexibleArrayMemberExpr(CE->getSubExpr())) {
967 IndexedType = CE->getSubExpr()->getType();
968 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe();
969 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT))
970 return CGF.Builder.getInt(CAT->getSize());
971 else if (const auto *VAT = dyn_cast<VariableArrayType>(AT))
972 return CGF.getVLASize(VAT).NumElts;
973 // Ignore pass_object_size here. It's not applicable on decayed pointers.
977 QualType EltTy{Base->getType()->getPointeeOrArrayElementType(), 0};
978 if (llvm::Value *POS = CGF.LoadPassedObjectSize(Base, EltTy)) {
979 IndexedType = Base->getType();
986 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base,
987 llvm::Value *Index, QualType IndexType,
989 assert(SanOpts.has(SanitizerKind::ArrayBounds) &&
990 "should not be called unless adding bounds checks");
991 SanitizerScope SanScope(this);
993 QualType IndexedType;
994 llvm::Value *Bound = getArrayIndexingBound(*this, Base, IndexedType);
998 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType();
999 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned);
1000 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false);
1002 llvm::Constant *StaticData[] = {
1003 EmitCheckSourceLocation(E->getExprLoc()),
1004 EmitCheckTypeDescriptor(IndexedType),
1005 EmitCheckTypeDescriptor(IndexType)
1007 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal)
1008 : Builder.CreateICmpULE(IndexVal, BoundVal);
1009 EmitCheck(std::make_pair(Check, SanitizerKind::ArrayBounds),
1010 SanitizerHandler::OutOfBounds, StaticData, Index);
1014 CodeGenFunction::ComplexPairTy CodeGenFunction::
1015 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
1016 bool isInc, bool isPre) {
1017 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc());
1019 llvm::Value *NextVal;
1020 if (isa<llvm::IntegerType>(InVal.first->getType())) {
1021 uint64_t AmountVal = isInc ? 1 : -1;
1022 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
1024 // Add the inc/dec to the real part.
1025 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
1027 QualType ElemTy = E->getType()->castAs<ComplexType>()->getElementType();
1028 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
1031 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
1033 // Add the inc/dec to the real part.
1034 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
1037 ComplexPairTy IncVal(NextVal, InVal.second);
1039 // Store the updated result through the lvalue.
1040 EmitStoreOfComplex(IncVal, LV, /*init*/ false);
1041 if (getLangOpts().OpenMP)
1042 CGM.getOpenMPRuntime().checkAndEmitLastprivateConditional(*this,
1045 // If this is a postinc, return the value read from memory, otherwise use the
1047 return isPre ? IncVal : InVal;
1050 void CodeGenModule::EmitExplicitCastExprType(const ExplicitCastExpr *E,
1051 CodeGenFunction *CGF) {
1052 // Bind VLAs in the cast type.
1053 if (CGF && E->getType()->isVariablyModifiedType())
1054 CGF->EmitVariablyModifiedType(E->getType());
1056 if (CGDebugInfo *DI = getModuleDebugInfo())
1057 DI->EmitExplicitCastType(E->getType());
1060 //===----------------------------------------------------------------------===//
1061 // LValue Expression Emission
1062 //===----------------------------------------------------------------------===//
1064 /// EmitPointerWithAlignment - Given an expression of pointer type, try to
1065 /// derive a more accurate bound on the alignment of the pointer.
1066 Address CodeGenFunction::EmitPointerWithAlignment(const Expr *E,
1067 LValueBaseInfo *BaseInfo,
1068 TBAAAccessInfo *TBAAInfo) {
1069 // We allow this with ObjC object pointers because of fragile ABIs.
1070 assert(E->getType()->isPointerType() ||
1071 E->getType()->isObjCObjectPointerType());
1072 E = E->IgnoreParens();
1075 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
1076 if (const auto *ECE = dyn_cast<ExplicitCastExpr>(CE))
1077 CGM.EmitExplicitCastExprType(ECE, this);
1079 switch (CE->getCastKind()) {
1080 // Non-converting casts (but not C's implicit conversion from void*).
1083 case CK_AddressSpaceConversion:
1084 if (auto PtrTy = CE->getSubExpr()->getType()->getAs<PointerType>()) {
1085 if (PtrTy->getPointeeType()->isVoidType())
1088 LValueBaseInfo InnerBaseInfo;
1089 TBAAAccessInfo InnerTBAAInfo;
1090 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(),
1093 if (BaseInfo) *BaseInfo = InnerBaseInfo;
1094 if (TBAAInfo) *TBAAInfo = InnerTBAAInfo;
1096 if (isa<ExplicitCastExpr>(CE)) {
1097 LValueBaseInfo TargetTypeBaseInfo;
1098 TBAAAccessInfo TargetTypeTBAAInfo;
1099 CharUnits Align = CGM.getNaturalPointeeTypeAlignment(
1100 E->getType(), &TargetTypeBaseInfo, &TargetTypeTBAAInfo);
1102 *TBAAInfo = CGM.mergeTBAAInfoForCast(*TBAAInfo,
1103 TargetTypeTBAAInfo);
1104 // If the source l-value is opaque, honor the alignment of the
1106 if (InnerBaseInfo.getAlignmentSource() != AlignmentSource::Decl) {
1108 BaseInfo->mergeForCast(TargetTypeBaseInfo);
1109 Addr = Address(Addr.getPointer(), Align);
1113 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast) &&
1114 CE->getCastKind() == CK_BitCast) {
1115 if (auto PT = E->getType()->getAs<PointerType>())
1116 EmitVTablePtrCheckForCast(PT->getPointeeType(), Addr.getPointer(),
1118 CodeGenFunction::CFITCK_UnrelatedCast,
1121 return CE->getCastKind() != CK_AddressSpaceConversion
1122 ? Builder.CreateBitCast(Addr, ConvertType(E->getType()))
1123 : Builder.CreateAddrSpaceCast(Addr,
1124 ConvertType(E->getType()));
1128 // Array-to-pointer decay.
1129 case CK_ArrayToPointerDecay:
1130 return EmitArrayToPointerDecay(CE->getSubExpr(), BaseInfo, TBAAInfo);
1132 // Derived-to-base conversions.
1133 case CK_UncheckedDerivedToBase:
1134 case CK_DerivedToBase: {
1135 // TODO: Support accesses to members of base classes in TBAA. For now, we
1136 // conservatively pretend that the complete object is of the base class
1139 *TBAAInfo = CGM.getTBAAAccessInfo(E->getType());
1140 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(), BaseInfo);
1141 auto Derived = CE->getSubExpr()->getType()->getPointeeCXXRecordDecl();
1142 return GetAddressOfBaseClass(Addr, Derived,
1143 CE->path_begin(), CE->path_end(),
1144 ShouldNullCheckClassCastValue(CE),
1148 // TODO: Is there any reason to treat base-to-derived conversions
1156 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
1157 if (UO->getOpcode() == UO_AddrOf) {
1158 LValue LV = EmitLValue(UO->getSubExpr());
1159 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
1160 if (TBAAInfo) *TBAAInfo = LV.getTBAAInfo();
1161 return LV.getAddress(*this);
1165 // TODO: conditional operators, comma.
1167 // Otherwise, use the alignment of the type.
1169 CGM.getNaturalPointeeTypeAlignment(E->getType(), BaseInfo, TBAAInfo);
1170 return Address(EmitScalarExpr(E), Align);
1173 RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
1174 if (Ty->isVoidType())
1175 return RValue::get(nullptr);
1177 switch (getEvaluationKind(Ty)) {
1180 ConvertType(Ty->castAs<ComplexType>()->getElementType());
1181 llvm::Value *U = llvm::UndefValue::get(EltTy);
1182 return RValue::getComplex(std::make_pair(U, U));
1185 // If this is a use of an undefined aggregate type, the aggregate must have an
1186 // identifiable address. Just because the contents of the value are undefined
1187 // doesn't mean that the address can't be taken and compared.
1188 case TEK_Aggregate: {
1189 Address DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
1190 return RValue::getAggregate(DestPtr);
1194 return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
1196 llvm_unreachable("bad evaluation kind");
1199 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
1201 ErrorUnsupported(E, Name);
1202 return GetUndefRValue(E->getType());
1205 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
1207 ErrorUnsupported(E, Name);
1208 llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
1209 return MakeAddrLValue(Address(llvm::UndefValue::get(Ty), CharUnits::One()),
1213 bool CodeGenFunction::IsWrappedCXXThis(const Expr *Obj) {
1214 const Expr *Base = Obj;
1215 while (!isa<CXXThisExpr>(Base)) {
1216 // The result of a dynamic_cast can be null.
1217 if (isa<CXXDynamicCastExpr>(Base))
1220 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
1221 Base = CE->getSubExpr();
1222 } else if (const auto *PE = dyn_cast<ParenExpr>(Base)) {
1223 Base = PE->getSubExpr();
1224 } else if (const auto *UO = dyn_cast<UnaryOperator>(Base)) {
1225 if (UO->getOpcode() == UO_Extension)
1226 Base = UO->getSubExpr();
1236 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) {
1238 if (SanOpts.has(SanitizerKind::ArrayBounds) && isa<ArraySubscriptExpr>(E))
1239 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true);
1242 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) {
1243 SanitizerSet SkippedChecks;
1244 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
1245 bool IsBaseCXXThis = IsWrappedCXXThis(ME->getBase());
1247 SkippedChecks.set(SanitizerKind::Alignment, true);
1248 if (IsBaseCXXThis || isa<DeclRefExpr>(ME->getBase()))
1249 SkippedChecks.set(SanitizerKind::Null, true);
1251 EmitTypeCheck(TCK, E->getExprLoc(), LV.getPointer(*this), E->getType(),
1252 LV.getAlignment(), SkippedChecks);
1257 /// EmitLValue - Emit code to compute a designator that specifies the location
1258 /// of the expression.
1260 /// This can return one of two things: a simple address or a bitfield reference.
1261 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be
1262 /// an LLVM pointer type.
1264 /// If this returns a bitfield reference, nothing about the pointee type of the
1265 /// LLVM value is known: For example, it may not be a pointer to an integer.
1267 /// If this returns a normal address, and if the lvalue's C type is fixed size,
1268 /// this method guarantees that the returned pointer type will point to an LLVM
1269 /// type of the same size of the lvalue's type. If the lvalue has a variable
1270 /// length type, this is not possible.
1272 LValue CodeGenFunction::EmitLValue(const Expr *E) {
1273 ApplyDebugLocation DL(*this, E);
1274 switch (E->getStmtClass()) {
1275 default: return EmitUnsupportedLValue(E, "l-value expression");
1277 case Expr::ObjCPropertyRefExprClass:
1278 llvm_unreachable("cannot emit a property reference directly");
1280 case Expr::ObjCSelectorExprClass:
1281 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
1282 case Expr::ObjCIsaExprClass:
1283 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
1284 case Expr::BinaryOperatorClass:
1285 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
1286 case Expr::CompoundAssignOperatorClass: {
1287 QualType Ty = E->getType();
1288 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1289 Ty = AT->getValueType();
1290 if (!Ty->isAnyComplexType())
1291 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1292 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1294 case Expr::CallExprClass:
1295 case Expr::CXXMemberCallExprClass:
1296 case Expr::CXXOperatorCallExprClass:
1297 case Expr::UserDefinedLiteralClass:
1298 return EmitCallExprLValue(cast<CallExpr>(E));
1299 case Expr::CXXRewrittenBinaryOperatorClass:
1300 return EmitLValue(cast<CXXRewrittenBinaryOperator>(E)->getSemanticForm());
1301 case Expr::VAArgExprClass:
1302 return EmitVAArgExprLValue(cast<VAArgExpr>(E));
1303 case Expr::DeclRefExprClass:
1304 return EmitDeclRefLValue(cast<DeclRefExpr>(E));
1305 case Expr::ConstantExprClass: {
1306 const ConstantExpr *CE = cast<ConstantExpr>(E);
1307 if (llvm::Value *Result = ConstantEmitter(*this).tryEmitConstantExpr(CE)) {
1308 QualType RetType = cast<CallExpr>(CE->getSubExpr()->IgnoreImplicit())
1309 ->getCallReturnType(getContext());
1310 return MakeNaturalAlignAddrLValue(Result, RetType);
1312 return EmitLValue(cast<ConstantExpr>(E)->getSubExpr());
1314 case Expr::ParenExprClass:
1315 return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
1316 case Expr::GenericSelectionExprClass:
1317 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr());
1318 case Expr::PredefinedExprClass:
1319 return EmitPredefinedLValue(cast<PredefinedExpr>(E));
1320 case Expr::StringLiteralClass:
1321 return EmitStringLiteralLValue(cast<StringLiteral>(E));
1322 case Expr::ObjCEncodeExprClass:
1323 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
1324 case Expr::PseudoObjectExprClass:
1325 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E));
1326 case Expr::InitListExprClass:
1327 return EmitInitListLValue(cast<InitListExpr>(E));
1328 case Expr::CXXTemporaryObjectExprClass:
1329 case Expr::CXXConstructExprClass:
1330 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
1331 case Expr::CXXBindTemporaryExprClass:
1332 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
1333 case Expr::CXXUuidofExprClass:
1334 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E));
1335 case Expr::LambdaExprClass:
1336 return EmitAggExprToLValue(E);
1338 case Expr::ExprWithCleanupsClass: {
1339 const auto *cleanups = cast<ExprWithCleanups>(E);
1340 RunCleanupsScope Scope(*this);
1341 LValue LV = EmitLValue(cleanups->getSubExpr());
1342 if (LV.isSimple()) {
1343 // Defend against branches out of gnu statement expressions surrounded by
1345 llvm::Value *V = LV.getPointer(*this);
1346 Scope.ForceCleanup({&V});
1347 return LValue::MakeAddr(Address(V, LV.getAlignment()), LV.getType(),
1348 getContext(), LV.getBaseInfo(), LV.getTBAAInfo());
1350 // FIXME: Is it possible to create an ExprWithCleanups that produces a
1351 // bitfield lvalue or some other non-simple lvalue?
1355 case Expr::CXXDefaultArgExprClass: {
1356 auto *DAE = cast<CXXDefaultArgExpr>(E);
1357 CXXDefaultArgExprScope Scope(*this, DAE);
1358 return EmitLValue(DAE->getExpr());
1360 case Expr::CXXDefaultInitExprClass: {
1361 auto *DIE = cast<CXXDefaultInitExpr>(E);
1362 CXXDefaultInitExprScope Scope(*this, DIE);
1363 return EmitLValue(DIE->getExpr());
1365 case Expr::CXXTypeidExprClass:
1366 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
1368 case Expr::ObjCMessageExprClass:
1369 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
1370 case Expr::ObjCIvarRefExprClass:
1371 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
1372 case Expr::StmtExprClass:
1373 return EmitStmtExprLValue(cast<StmtExpr>(E));
1374 case Expr::UnaryOperatorClass:
1375 return EmitUnaryOpLValue(cast<UnaryOperator>(E));
1376 case Expr::ArraySubscriptExprClass:
1377 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
1378 case Expr::MatrixSubscriptExprClass:
1379 return EmitMatrixSubscriptExpr(cast<MatrixSubscriptExpr>(E));
1380 case Expr::OMPArraySectionExprClass:
1381 return EmitOMPArraySectionExpr(cast<OMPArraySectionExpr>(E));
1382 case Expr::ExtVectorElementExprClass:
1383 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
1384 case Expr::MemberExprClass:
1385 return EmitMemberExpr(cast<MemberExpr>(E));
1386 case Expr::CompoundLiteralExprClass:
1387 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
1388 case Expr::ConditionalOperatorClass:
1389 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
1390 case Expr::BinaryConditionalOperatorClass:
1391 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
1392 case Expr::ChooseExprClass:
1393 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr());
1394 case Expr::OpaqueValueExprClass:
1395 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
1396 case Expr::SubstNonTypeTemplateParmExprClass:
1397 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement());
1398 case Expr::ImplicitCastExprClass:
1399 case Expr::CStyleCastExprClass:
1400 case Expr::CXXFunctionalCastExprClass:
1401 case Expr::CXXStaticCastExprClass:
1402 case Expr::CXXDynamicCastExprClass:
1403 case Expr::CXXReinterpretCastExprClass:
1404 case Expr::CXXConstCastExprClass:
1405 case Expr::CXXAddrspaceCastExprClass:
1406 case Expr::ObjCBridgedCastExprClass:
1407 return EmitCastLValue(cast<CastExpr>(E));
1409 case Expr::MaterializeTemporaryExprClass:
1410 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E));
1412 case Expr::CoawaitExprClass:
1413 return EmitCoawaitLValue(cast<CoawaitExpr>(E));
1414 case Expr::CoyieldExprClass:
1415 return EmitCoyieldLValue(cast<CoyieldExpr>(E));
1419 /// Given an object of the given canonical type, can we safely copy a
1420 /// value out of it based on its initializer?
1421 static bool isConstantEmittableObjectType(QualType type) {
1422 assert(type.isCanonical());
1423 assert(!type->isReferenceType());
1425 // Must be const-qualified but non-volatile.
1426 Qualifiers qs = type.getLocalQualifiers();
1427 if (!qs.hasConst() || qs.hasVolatile()) return false;
1429 // Otherwise, all object types satisfy this except C++ classes with
1430 // mutable subobjects or non-trivial copy/destroy behavior.
1431 if (const auto *RT = dyn_cast<RecordType>(type))
1432 if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
1433 if (RD->hasMutableFields() || !RD->isTrivial())
1439 /// Can we constant-emit a load of a reference to a variable of the
1440 /// given type? This is different from predicates like
1441 /// Decl::mightBeUsableInConstantExpressions because we do want it to apply
1442 /// in situations that don't necessarily satisfy the language's rules
1443 /// for this (e.g. C++'s ODR-use rules). For example, we want to able
1444 /// to do this with const float variables even if those variables
1445 /// aren't marked 'constexpr'.
1446 enum ConstantEmissionKind {
1448 CEK_AsReferenceOnly,
1449 CEK_AsValueOrReference,
1452 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) {
1453 type = type.getCanonicalType();
1454 if (const auto *ref = dyn_cast<ReferenceType>(type)) {
1455 if (isConstantEmittableObjectType(ref->getPointeeType()))
1456 return CEK_AsValueOrReference;
1457 return CEK_AsReferenceOnly;
1459 if (isConstantEmittableObjectType(type))
1460 return CEK_AsValueOnly;
1464 /// Try to emit a reference to the given value without producing it as
1465 /// an l-value. This is just an optimization, but it avoids us needing
1466 /// to emit global copies of variables if they're named without triggering
1467 /// a formal use in a context where we can't emit a direct reference to them,
1468 /// for instance if a block or lambda or a member of a local class uses a
1469 /// const int variable or constexpr variable from an enclosing function.
1470 CodeGenFunction::ConstantEmission
1471 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) {
1472 ValueDecl *value = refExpr->getDecl();
1474 // The value needs to be an enum constant or a constant variable.
1475 ConstantEmissionKind CEK;
1476 if (isa<ParmVarDecl>(value)) {
1478 } else if (auto *var = dyn_cast<VarDecl>(value)) {
1479 CEK = checkVarTypeForConstantEmission(var->getType());
1480 } else if (isa<EnumConstantDecl>(value)) {
1481 CEK = CEK_AsValueOnly;
1485 if (CEK == CEK_None) return ConstantEmission();
1487 Expr::EvalResult result;
1488 bool resultIsReference;
1489 QualType resultType;
1491 // It's best to evaluate all the way as an r-value if that's permitted.
1492 if (CEK != CEK_AsReferenceOnly &&
1493 refExpr->EvaluateAsRValue(result, getContext())) {
1494 resultIsReference = false;
1495 resultType = refExpr->getType();
1497 // Otherwise, try to evaluate as an l-value.
1498 } else if (CEK != CEK_AsValueOnly &&
1499 refExpr->EvaluateAsLValue(result, getContext())) {
1500 resultIsReference = true;
1501 resultType = value->getType();
1505 return ConstantEmission();
1508 // In any case, if the initializer has side-effects, abandon ship.
1509 if (result.HasSideEffects)
1510 return ConstantEmission();
1512 // Emit as a constant.
1513 auto C = ConstantEmitter(*this).emitAbstract(refExpr->getLocation(),
1514 result.Val, resultType);
1516 // Make sure we emit a debug reference to the global variable.
1517 // This should probably fire even for
1518 if (isa<VarDecl>(value)) {
1519 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value)))
1520 EmitDeclRefExprDbgValue(refExpr, result.Val);
1522 assert(isa<EnumConstantDecl>(value));
1523 EmitDeclRefExprDbgValue(refExpr, result.Val);
1526 // If we emitted a reference constant, we need to dereference that.
1527 if (resultIsReference)
1528 return ConstantEmission::forReference(C);
1530 return ConstantEmission::forValue(C);
1533 static DeclRefExpr *tryToConvertMemberExprToDeclRefExpr(CodeGenFunction &CGF,
1534 const MemberExpr *ME) {
1535 if (auto *VD = dyn_cast<VarDecl>(ME->getMemberDecl())) {
1536 // Try to emit static variable member expressions as DREs.
1537 return DeclRefExpr::Create(
1538 CGF.getContext(), NestedNameSpecifierLoc(), SourceLocation(), VD,
1539 /*RefersToEnclosingVariableOrCapture=*/false, ME->getExprLoc(),
1540 ME->getType(), ME->getValueKind(), nullptr, nullptr, ME->isNonOdrUse());
1545 CodeGenFunction::ConstantEmission
1546 CodeGenFunction::tryEmitAsConstant(const MemberExpr *ME) {
1547 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, ME))
1548 return tryEmitAsConstant(DRE);
1549 return ConstantEmission();
1552 llvm::Value *CodeGenFunction::emitScalarConstant(
1553 const CodeGenFunction::ConstantEmission &Constant, Expr *E) {
1554 assert(Constant && "not a constant");
1555 if (Constant.isReference())
1556 return EmitLoadOfLValue(Constant.getReferenceLValue(*this, E),
1559 return Constant.getValue();
1562 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue,
1563 SourceLocation Loc) {
1564 return EmitLoadOfScalar(lvalue.getAddress(*this), lvalue.isVolatile(),
1565 lvalue.getType(), Loc, lvalue.getBaseInfo(),
1566 lvalue.getTBAAInfo(), lvalue.isNontemporal());
1569 static bool hasBooleanRepresentation(QualType Ty) {
1570 if (Ty->isBooleanType())
1573 if (const EnumType *ET = Ty->getAs<EnumType>())
1574 return ET->getDecl()->getIntegerType()->isBooleanType();
1576 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1577 return hasBooleanRepresentation(AT->getValueType());
1582 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty,
1583 llvm::APInt &Min, llvm::APInt &End,
1584 bool StrictEnums, bool IsBool) {
1585 const EnumType *ET = Ty->getAs<EnumType>();
1586 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums &&
1587 ET && !ET->getDecl()->isFixed();
1588 if (!IsBool && !IsRegularCPlusPlusEnum)
1592 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0);
1593 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2);
1595 const EnumDecl *ED = ET->getDecl();
1596 llvm::Type *LTy = CGF.ConvertTypeForMem(ED->getIntegerType());
1597 unsigned Bitwidth = LTy->getScalarSizeInBits();
1598 unsigned NumNegativeBits = ED->getNumNegativeBits();
1599 unsigned NumPositiveBits = ED->getNumPositiveBits();
1601 if (NumNegativeBits) {
1602 unsigned NumBits = std::max(NumNegativeBits, NumPositiveBits + 1);
1603 assert(NumBits <= Bitwidth);
1604 End = llvm::APInt(Bitwidth, 1) << (NumBits - 1);
1607 assert(NumPositiveBits <= Bitwidth);
1608 End = llvm::APInt(Bitwidth, 1) << NumPositiveBits;
1609 Min = llvm::APInt(Bitwidth, 0);
1615 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) {
1616 llvm::APInt Min, End;
1617 if (!getRangeForType(*this, Ty, Min, End, CGM.getCodeGenOpts().StrictEnums,
1618 hasBooleanRepresentation(Ty)))
1621 llvm::MDBuilder MDHelper(getLLVMContext());
1622 return MDHelper.createRange(Min, End);
1625 bool CodeGenFunction::EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
1626 SourceLocation Loc) {
1627 bool HasBoolCheck = SanOpts.has(SanitizerKind::Bool);
1628 bool HasEnumCheck = SanOpts.has(SanitizerKind::Enum);
1629 if (!HasBoolCheck && !HasEnumCheck)
1632 bool IsBool = hasBooleanRepresentation(Ty) ||
1633 NSAPI(CGM.getContext()).isObjCBOOLType(Ty);
1634 bool NeedsBoolCheck = HasBoolCheck && IsBool;
1635 bool NeedsEnumCheck = HasEnumCheck && Ty->getAs<EnumType>();
1636 if (!NeedsBoolCheck && !NeedsEnumCheck)
1639 // Single-bit booleans don't need to be checked. Special-case this to avoid
1640 // a bit width mismatch when handling bitfield values. This is handled by
1641 // EmitFromMemory for the non-bitfield case.
1643 cast<llvm::IntegerType>(Value->getType())->getBitWidth() == 1)
1646 llvm::APInt Min, End;
1647 if (!getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true, IsBool))
1650 auto &Ctx = getLLVMContext();
1651 SanitizerScope SanScope(this);
1655 Check = Builder.CreateICmpULE(Value, llvm::ConstantInt::get(Ctx, End));
1657 llvm::Value *Upper =
1658 Builder.CreateICmpSLE(Value, llvm::ConstantInt::get(Ctx, End));
1659 llvm::Value *Lower =
1660 Builder.CreateICmpSGE(Value, llvm::ConstantInt::get(Ctx, Min));
1661 Check = Builder.CreateAnd(Upper, Lower);
1663 llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc),
1664 EmitCheckTypeDescriptor(Ty)};
1665 SanitizerMask Kind =
1666 NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool;
1667 EmitCheck(std::make_pair(Check, Kind), SanitizerHandler::LoadInvalidValue,
1668 StaticArgs, EmitCheckValue(Value));
1672 llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile,
1675 LValueBaseInfo BaseInfo,
1676 TBAAAccessInfo TBAAInfo,
1677 bool isNontemporal) {
1678 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1679 // For better performance, handle vector loads differently.
1680 if (Ty->isVectorType()) {
1681 const llvm::Type *EltTy = Addr.getElementType();
1683 const auto *VTy = cast<llvm::VectorType>(EltTy);
1685 // Handle vectors of size 3 like size 4 for better performance.
1686 if (VTy->getNumElements() == 3) {
1688 // Bitcast to vec4 type.
1689 auto *vec4Ty = llvm::FixedVectorType::get(VTy->getElementType(), 4);
1690 Address Cast = Builder.CreateElementBitCast(Addr, vec4Ty, "castToVec4");
1692 llvm::Value *V = Builder.CreateLoad(Cast, Volatile, "loadVec4");
1694 // Shuffle vector to get vec3.
1695 V = Builder.CreateShuffleVector(V, llvm::UndefValue::get(vec4Ty),
1696 ArrayRef<int>{0, 1, 2}, "extractVec");
1697 return EmitFromMemory(V, Ty);
1702 // Atomic operations have to be done on integral types.
1703 LValue AtomicLValue =
1704 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1705 if (Ty->isAtomicType() || LValueIsSuitableForInlineAtomic(AtomicLValue)) {
1706 return EmitAtomicLoad(AtomicLValue, Loc).getScalarVal();
1709 llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile);
1710 if (isNontemporal) {
1711 llvm::MDNode *Node = llvm::MDNode::get(
1712 Load->getContext(), llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1713 Load->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1716 CGM.DecorateInstructionWithTBAA(Load, TBAAInfo);
1718 if (EmitScalarRangeCheck(Load, Ty, Loc)) {
1719 // In order to prevent the optimizer from throwing away the check, don't
1720 // attach range metadata to the load.
1721 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0)
1722 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty))
1723 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo);
1725 return EmitFromMemory(Load, Ty);
1728 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
1729 // Bool has a different representation in memory than in registers.
1730 if (hasBooleanRepresentation(Ty)) {
1731 // This should really always be an i1, but sometimes it's already
1732 // an i8, and it's awkward to track those cases down.
1733 if (Value->getType()->isIntegerTy(1))
1734 return Builder.CreateZExt(Value, ConvertTypeForMem(Ty), "frombool");
1735 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1736 "wrong value rep of bool");
1742 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
1743 // Bool has a different representation in memory than in registers.
1744 if (hasBooleanRepresentation(Ty)) {
1745 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1746 "wrong value rep of bool");
1747 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool");
1753 // Convert the pointer of \p Addr to a pointer to a vector (the value type of
1754 // MatrixType), if it points to a array (the memory type of MatrixType).
1755 static Address MaybeConvertMatrixAddress(Address Addr, CodeGenFunction &CGF,
1756 bool IsVector = true) {
1757 auto *ArrayTy = dyn_cast<llvm::ArrayType>(
1758 cast<llvm::PointerType>(Addr.getPointer()->getType())->getElementType());
1759 if (ArrayTy && IsVector) {
1760 auto *VectorTy = llvm::FixedVectorType::get(ArrayTy->getElementType(),
1761 ArrayTy->getNumElements());
1763 return Address(CGF.Builder.CreateElementBitCast(Addr, VectorTy));
1765 auto *VectorTy = dyn_cast<llvm::VectorType>(
1766 cast<llvm::PointerType>(Addr.getPointer()->getType())->getElementType());
1767 if (VectorTy && !IsVector) {
1768 auto *ArrayTy = llvm::ArrayType::get(VectorTy->getElementType(),
1769 VectorTy->getNumElements());
1771 return Address(CGF.Builder.CreateElementBitCast(Addr, ArrayTy));
1777 // Emit a store of a matrix LValue. This may require casting the original
1778 // pointer to memory address (ArrayType) to a pointer to the value type
1780 static void EmitStoreOfMatrixScalar(llvm::Value *value, LValue lvalue,
1781 bool isInit, CodeGenFunction &CGF) {
1782 Address Addr = MaybeConvertMatrixAddress(lvalue.getAddress(CGF), CGF,
1783 value->getType()->isVectorTy());
1784 CGF.EmitStoreOfScalar(value, Addr, lvalue.isVolatile(), lvalue.getType(),
1785 lvalue.getBaseInfo(), lvalue.getTBAAInfo(), isInit,
1786 lvalue.isNontemporal());
1789 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr,
1790 bool Volatile, QualType Ty,
1791 LValueBaseInfo BaseInfo,
1792 TBAAAccessInfo TBAAInfo,
1793 bool isInit, bool isNontemporal) {
1794 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1795 // Handle vectors differently to get better performance.
1796 if (Ty->isVectorType()) {
1797 llvm::Type *SrcTy = Value->getType();
1798 auto *VecTy = dyn_cast<llvm::VectorType>(SrcTy);
1799 // Handle vec3 special.
1800 if (VecTy && VecTy->getNumElements() == 3) {
1801 // Our source is a vec3, do a shuffle vector to make it a vec4.
1802 Value = Builder.CreateShuffleVector(Value, llvm::UndefValue::get(VecTy),
1803 ArrayRef<int>{0, 1, 2, -1},
1805 SrcTy = llvm::FixedVectorType::get(VecTy->getElementType(), 4);
1807 if (Addr.getElementType() != SrcTy) {
1808 Addr = Builder.CreateElementBitCast(Addr, SrcTy, "storetmp");
1813 Value = EmitToMemory(Value, Ty);
1815 LValue AtomicLValue =
1816 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1817 if (Ty->isAtomicType() ||
1818 (!isInit && LValueIsSuitableForInlineAtomic(AtomicLValue))) {
1819 EmitAtomicStore(RValue::get(Value), AtomicLValue, isInit);
1823 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
1824 if (isNontemporal) {
1825 llvm::MDNode *Node =
1826 llvm::MDNode::get(Store->getContext(),
1827 llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1828 Store->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1831 CGM.DecorateInstructionWithTBAA(Store, TBAAInfo);
1834 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue,
1836 if (lvalue.getType()->isConstantMatrixType()) {
1837 EmitStoreOfMatrixScalar(value, lvalue, isInit, *this);
1841 EmitStoreOfScalar(value, lvalue.getAddress(*this), lvalue.isVolatile(),
1842 lvalue.getType(), lvalue.getBaseInfo(),
1843 lvalue.getTBAAInfo(), isInit, lvalue.isNontemporal());
1846 // Emit a load of a LValue of matrix type. This may require casting the pointer
1847 // to memory address (ArrayType) to a pointer to the value type (VectorType).
1848 static RValue EmitLoadOfMatrixLValue(LValue LV, SourceLocation Loc,
1849 CodeGenFunction &CGF) {
1850 assert(LV.getType()->isConstantMatrixType());
1851 Address Addr = MaybeConvertMatrixAddress(LV.getAddress(CGF), CGF);
1852 LV.setAddress(Addr);
1853 return RValue::get(CGF.EmitLoadOfScalar(LV, Loc));
1856 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
1857 /// method emits the address of the lvalue, then loads the result as an rvalue,
1858 /// returning the rvalue.
1859 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
1860 if (LV.isObjCWeak()) {
1861 // load of a __weak object.
1862 Address AddrWeakObj = LV.getAddress(*this);
1863 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
1866 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
1867 // In MRC mode, we do a load+autorelease.
1868 if (!getLangOpts().ObjCAutoRefCount) {
1869 return RValue::get(EmitARCLoadWeak(LV.getAddress(*this)));
1872 // In ARC mode, we load retained and then consume the value.
1873 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress(*this));
1874 Object = EmitObjCConsumeObject(LV.getType(), Object);
1875 return RValue::get(Object);
1878 if (LV.isSimple()) {
1879 assert(!LV.getType()->isFunctionType());
1881 if (LV.getType()->isConstantMatrixType())
1882 return EmitLoadOfMatrixLValue(LV, Loc, *this);
1884 // Everything needs a load.
1885 return RValue::get(EmitLoadOfScalar(LV, Loc));
1888 if (LV.isVectorElt()) {
1889 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddress(),
1890 LV.isVolatileQualified());
1891 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(),
1895 // If this is a reference to a subset of the elements of a vector, either
1896 // shuffle the input or extract/insert them as appropriate.
1897 if (LV.isExtVectorElt()) {
1898 return EmitLoadOfExtVectorElementLValue(LV);
1901 // Global Register variables always invoke intrinsics
1902 if (LV.isGlobalReg())
1903 return EmitLoadOfGlobalRegLValue(LV);
1905 if (LV.isMatrixElt()) {
1906 llvm::LoadInst *Load =
1907 Builder.CreateLoad(LV.getMatrixAddress(), LV.isVolatileQualified());
1909 Builder.CreateExtractElement(Load, LV.getMatrixIdx(), "matrixext"));
1912 assert(LV.isBitField() && "Unknown LValue type!");
1913 return EmitLoadOfBitfieldLValue(LV, Loc);
1916 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
1917 SourceLocation Loc) {
1918 const CGBitFieldInfo &Info = LV.getBitFieldInfo();
1920 // Get the output type.
1921 llvm::Type *ResLTy = ConvertType(LV.getType());
1923 Address Ptr = LV.getBitFieldAddress();
1924 llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "bf.load");
1926 if (Info.IsSigned) {
1927 assert(static_cast<unsigned>(Info.Offset + Info.Size) <= Info.StorageSize);
1928 unsigned HighBits = Info.StorageSize - Info.Offset - Info.Size;
1930 Val = Builder.CreateShl(Val, HighBits, "bf.shl");
1931 if (Info.Offset + HighBits)
1932 Val = Builder.CreateAShr(Val, Info.Offset + HighBits, "bf.ashr");
1935 Val = Builder.CreateLShr(Val, Info.Offset, "bf.lshr");
1936 if (static_cast<unsigned>(Info.Offset) + Info.Size < Info.StorageSize)
1937 Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(Info.StorageSize,
1941 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast");
1942 EmitScalarRangeCheck(Val, LV.getType(), Loc);
1943 return RValue::get(Val);
1946 // If this is a reference to a subset of the elements of a vector, create an
1947 // appropriate shufflevector.
1948 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) {
1949 llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddress(),
1950 LV.isVolatileQualified());
1952 const llvm::Constant *Elts = LV.getExtVectorElts();
1954 // If the result of the expression is a non-vector type, we must be extracting
1955 // a single element. Just codegen as an extractelement.
1956 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1958 unsigned InIdx = getAccessedFieldNo(0, Elts);
1959 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1960 return RValue::get(Builder.CreateExtractElement(Vec, Elt));
1963 // Always use shuffle vector to try to retain the original program structure
1964 unsigned NumResultElts = ExprVT->getNumElements();
1966 SmallVector<int, 4> Mask;
1967 for (unsigned i = 0; i != NumResultElts; ++i)
1968 Mask.push_back(getAccessedFieldNo(i, Elts));
1970 Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()),
1972 return RValue::get(Vec);
1975 /// Generates lvalue for partial ext_vector access.
1976 Address CodeGenFunction::EmitExtVectorElementLValue(LValue LV) {
1977 Address VectorAddress = LV.getExtVectorAddress();
1978 QualType EQT = LV.getType()->castAs<VectorType>()->getElementType();
1979 llvm::Type *VectorElementTy = CGM.getTypes().ConvertType(EQT);
1981 Address CastToPointerElement =
1982 Builder.CreateElementBitCast(VectorAddress, VectorElementTy,
1983 "conv.ptr.element");
1985 const llvm::Constant *Elts = LV.getExtVectorElts();
1986 unsigned ix = getAccessedFieldNo(0, Elts);
1988 Address VectorBasePtrPlusIx =
1989 Builder.CreateConstInBoundsGEP(CastToPointerElement, ix,
1992 return VectorBasePtrPlusIx;
1995 /// Load of global gamed gegisters are always calls to intrinsics.
1996 RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) {
1997 assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) &&
1998 "Bad type for register variable");
1999 llvm::MDNode *RegName = cast<llvm::MDNode>(
2000 cast<llvm::MetadataAsValue>(LV.getGlobalReg())->getMetadata());
2002 // We accept integer and pointer types only
2003 llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType());
2004 llvm::Type *Ty = OrigTy;
2005 if (OrigTy->isPointerTy())
2006 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
2007 llvm::Type *Types[] = { Ty };
2009 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types);
2010 llvm::Value *Call = Builder.CreateCall(
2011 F, llvm::MetadataAsValue::get(Ty->getContext(), RegName));
2012 if (OrigTy->isPointerTy())
2013 Call = Builder.CreateIntToPtr(Call, OrigTy);
2014 return RValue::get(Call);
2017 /// EmitStoreThroughLValue - Store the specified rvalue into the specified
2018 /// lvalue, where both are guaranteed to the have the same type, and that type
2020 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
2022 if (!Dst.isSimple()) {
2023 if (Dst.isVectorElt()) {
2024 // Read/modify/write the vector, inserting the new element.
2025 llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddress(),
2026 Dst.isVolatileQualified());
2027 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
2028 Dst.getVectorIdx(), "vecins");
2029 Builder.CreateStore(Vec, Dst.getVectorAddress(),
2030 Dst.isVolatileQualified());
2034 // If this is an update of extended vector elements, insert them as
2036 if (Dst.isExtVectorElt())
2037 return EmitStoreThroughExtVectorComponentLValue(Src, Dst);
2039 if (Dst.isGlobalReg())
2040 return EmitStoreThroughGlobalRegLValue(Src, Dst);
2042 if (Dst.isMatrixElt()) {
2043 llvm::Value *Vec = Builder.CreateLoad(Dst.getMatrixAddress());
2044 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
2045 Dst.getMatrixIdx(), "matins");
2046 Builder.CreateStore(Vec, Dst.getMatrixAddress(),
2047 Dst.isVolatileQualified());
2051 assert(Dst.isBitField() && "Unknown LValue type");
2052 return EmitStoreThroughBitfieldLValue(Src, Dst);
2055 // There's special magic for assigning into an ARC-qualified l-value.
2056 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) {
2058 case Qualifiers::OCL_None:
2059 llvm_unreachable("present but none");
2061 case Qualifiers::OCL_ExplicitNone:
2065 case Qualifiers::OCL_Strong:
2067 Src = RValue::get(EmitARCRetain(Dst.getType(), Src.getScalarVal()));
2070 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true);
2073 case Qualifiers::OCL_Weak:
2075 // Initialize and then skip the primitive store.
2076 EmitARCInitWeak(Dst.getAddress(*this), Src.getScalarVal());
2078 EmitARCStoreWeak(Dst.getAddress(*this), Src.getScalarVal(),
2082 case Qualifiers::OCL_Autoreleasing:
2083 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(),
2084 Src.getScalarVal()));
2085 // fall into the normal path
2090 if (Dst.isObjCWeak() && !Dst.isNonGC()) {
2091 // load of a __weak object.
2092 Address LvalueDst = Dst.getAddress(*this);
2093 llvm::Value *src = Src.getScalarVal();
2094 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
2098 if (Dst.isObjCStrong() && !Dst.isNonGC()) {
2099 // load of a __strong object.
2100 Address LvalueDst = Dst.getAddress(*this);
2101 llvm::Value *src = Src.getScalarVal();
2102 if (Dst.isObjCIvar()) {
2103 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
2104 llvm::Type *ResultType = IntPtrTy;
2105 Address dst = EmitPointerWithAlignment(Dst.getBaseIvarExp());
2106 llvm::Value *RHS = dst.getPointer();
2107 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
2109 Builder.CreatePtrToInt(LvalueDst.getPointer(), ResultType,
2110 "sub.ptr.lhs.cast");
2111 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
2112 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
2114 } else if (Dst.isGlobalObjCRef()) {
2115 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
2116 Dst.isThreadLocalRef());
2119 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
2123 assert(Src.isScalar() && "Can't emit an agg store with this method");
2124 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit);
2127 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
2128 llvm::Value **Result) {
2129 const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
2130 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType());
2131 Address Ptr = Dst.getBitFieldAddress();
2133 // Get the source value, truncated to the width of the bit-field.
2134 llvm::Value *SrcVal = Src.getScalarVal();
2136 // Cast the source to the storage type and shift it into place.
2137 SrcVal = Builder.CreateIntCast(SrcVal, Ptr.getElementType(),
2138 /*isSigned=*/false);
2139 llvm::Value *MaskedVal = SrcVal;
2141 // See if there are other bits in the bitfield's storage we'll need to load
2142 // and mask together with source before storing.
2143 if (Info.StorageSize != Info.Size) {
2144 assert(Info.StorageSize > Info.Size && "Invalid bitfield size.");
2146 Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.load");
2148 // Mask the source value as needed.
2149 if (!hasBooleanRepresentation(Dst.getType()))
2150 SrcVal = Builder.CreateAnd(SrcVal,
2151 llvm::APInt::getLowBitsSet(Info.StorageSize,
2156 SrcVal = Builder.CreateShl(SrcVal, Info.Offset, "bf.shl");
2158 // Mask out the original value.
2159 Val = Builder.CreateAnd(Val,
2160 ~llvm::APInt::getBitsSet(Info.StorageSize,
2162 Info.Offset + Info.Size),
2165 // Or together the unchanged values and the source value.
2166 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set");
2168 assert(Info.Offset == 0);
2169 // According to the AACPS:
2170 // When a volatile bit-field is written, and its container does not overlap
2171 // with any non-bit-field member, its container must be read exactly once and
2172 // written exactly once using the access width appropriate to the type of the
2173 // container. The two accesses are not atomic.
2174 if (Dst.isVolatileQualified() && isAAPCS(CGM.getTarget()) &&
2175 CGM.getCodeGenOpts().ForceAAPCSBitfieldLoad)
2176 Builder.CreateLoad(Ptr, true, "bf.load");
2179 // Write the new value back out.
2180 Builder.CreateStore(SrcVal, Ptr, Dst.isVolatileQualified());
2182 // Return the new value of the bit-field, if requested.
2184 llvm::Value *ResultVal = MaskedVal;
2186 // Sign extend the value if needed.
2187 if (Info.IsSigned) {
2188 assert(Info.Size <= Info.StorageSize);
2189 unsigned HighBits = Info.StorageSize - Info.Size;
2191 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl");
2192 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr");
2196 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned,
2198 *Result = EmitFromMemory(ResultVal, Dst.getType());
2202 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
2204 // This access turns into a read/modify/write of the vector. Load the input
2206 llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddress(),
2207 Dst.isVolatileQualified());
2208 const llvm::Constant *Elts = Dst.getExtVectorElts();
2210 llvm::Value *SrcVal = Src.getScalarVal();
2212 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) {
2213 unsigned NumSrcElts = VTy->getNumElements();
2214 unsigned NumDstElts =
2215 cast<llvm::VectorType>(Vec->getType())->getNumElements();
2216 if (NumDstElts == NumSrcElts) {
2217 // Use shuffle vector is the src and destination are the same number of
2218 // elements and restore the vector mask since it is on the side it will be
2220 SmallVector<int, 4> Mask(NumDstElts);
2221 for (unsigned i = 0; i != NumSrcElts; ++i)
2222 Mask[getAccessedFieldNo(i, Elts)] = i;
2224 Vec = Builder.CreateShuffleVector(
2225 SrcVal, llvm::UndefValue::get(Vec->getType()), Mask);
2226 } else if (NumDstElts > NumSrcElts) {
2227 // Extended the source vector to the same length and then shuffle it
2228 // into the destination.
2229 // FIXME: since we're shuffling with undef, can we just use the indices
2230 // into that? This could be simpler.
2231 SmallVector<int, 4> ExtMask;
2232 for (unsigned i = 0; i != NumSrcElts; ++i)
2233 ExtMask.push_back(i);
2234 ExtMask.resize(NumDstElts, -1);
2235 llvm::Value *ExtSrcVal = Builder.CreateShuffleVector(
2236 SrcVal, llvm::UndefValue::get(SrcVal->getType()), ExtMask);
2238 SmallVector<int, 4> Mask;
2239 for (unsigned i = 0; i != NumDstElts; ++i)
2242 // When the vector size is odd and .odd or .hi is used, the last element
2243 // of the Elts constant array will be one past the size of the vector.
2244 // Ignore the last element here, if it is greater than the mask size.
2245 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size())
2248 // modify when what gets shuffled in
2249 for (unsigned i = 0; i != NumSrcElts; ++i)
2250 Mask[getAccessedFieldNo(i, Elts)] = i + NumDstElts;
2251 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, Mask);
2253 // We should never shorten the vector
2254 llvm_unreachable("unexpected shorten vector length");
2257 // If the Src is a scalar (not a vector) it must be updating one element.
2258 unsigned InIdx = getAccessedFieldNo(0, Elts);
2259 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
2260 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt);
2263 Builder.CreateStore(Vec, Dst.getExtVectorAddress(),
2264 Dst.isVolatileQualified());
2267 /// Store of global named registers are always calls to intrinsics.
2268 void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) {
2269 assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) &&
2270 "Bad type for register variable");
2271 llvm::MDNode *RegName = cast<llvm::MDNode>(
2272 cast<llvm::MetadataAsValue>(Dst.getGlobalReg())->getMetadata());
2273 assert(RegName && "Register LValue is not metadata");
2275 // We accept integer and pointer types only
2276 llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType());
2277 llvm::Type *Ty = OrigTy;
2278 if (OrigTy->isPointerTy())
2279 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
2280 llvm::Type *Types[] = { Ty };
2282 llvm::Function *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types);
2283 llvm::Value *Value = Src.getScalarVal();
2284 if (OrigTy->isPointerTy())
2285 Value = Builder.CreatePtrToInt(Value, Ty);
2287 F, {llvm::MetadataAsValue::get(Ty->getContext(), RegName), Value});
2290 // setObjCGCLValueClass - sets class of the lvalue for the purpose of
2291 // generating write-barries API. It is currently a global, ivar,
2293 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
2295 bool IsMemberAccess=false) {
2296 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC)
2299 if (isa<ObjCIvarRefExpr>(E)) {
2300 QualType ExpTy = E->getType();
2301 if (IsMemberAccess && ExpTy->isPointerType()) {
2302 // If ivar is a structure pointer, assigning to field of
2303 // this struct follows gcc's behavior and makes it a non-ivar
2304 // writer-barrier conservatively.
2305 ExpTy = ExpTy->castAs<PointerType>()->getPointeeType();
2306 if (ExpTy->isRecordType()) {
2307 LV.setObjCIvar(false);
2311 LV.setObjCIvar(true);
2312 auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E));
2313 LV.setBaseIvarExp(Exp->getBase());
2314 LV.setObjCArray(E->getType()->isArrayType());
2318 if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) {
2319 if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
2320 if (VD->hasGlobalStorage()) {
2321 LV.setGlobalObjCRef(true);
2322 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None);
2325 LV.setObjCArray(E->getType()->isArrayType());
2329 if (const auto *Exp = dyn_cast<UnaryOperator>(E)) {
2330 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2334 if (const auto *Exp = dyn_cast<ParenExpr>(E)) {
2335 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2336 if (LV.isObjCIvar()) {
2337 // If cast is to a structure pointer, follow gcc's behavior and make it
2338 // a non-ivar write-barrier.
2339 QualType ExpTy = E->getType();
2340 if (ExpTy->isPointerType())
2341 ExpTy = ExpTy->castAs<PointerType>()->getPointeeType();
2342 if (ExpTy->isRecordType())
2343 LV.setObjCIvar(false);
2348 if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) {
2349 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV);
2353 if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) {
2354 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2358 if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) {
2359 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2363 if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) {
2364 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2368 if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
2369 setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
2370 if (LV.isObjCIvar() && !LV.isObjCArray())
2371 // Using array syntax to assigning to what an ivar points to is not
2372 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
2373 LV.setObjCIvar(false);
2374 else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
2375 // Using array syntax to assigning to what global points to is not
2376 // same as assigning to the global itself. {id *G;} G[i] = 0;
2377 LV.setGlobalObjCRef(false);
2381 if (const auto *Exp = dyn_cast<MemberExpr>(E)) {
2382 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true);
2383 // We don't know if member is an 'ivar', but this flag is looked at
2384 // only in the context of LV.isObjCIvar().
2385 LV.setObjCArray(E->getType()->isArrayType());
2390 static llvm::Value *
2391 EmitBitCastOfLValueToProperType(CodeGenFunction &CGF,
2392 llvm::Value *V, llvm::Type *IRType,
2393 StringRef Name = StringRef()) {
2394 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace();
2395 return CGF.Builder.CreateBitCast(V, IRType->getPointerTo(AS), Name);
2398 static LValue EmitThreadPrivateVarDeclLValue(
2399 CodeGenFunction &CGF, const VarDecl *VD, QualType T, Address Addr,
2400 llvm::Type *RealVarTy, SourceLocation Loc) {
2401 if (CGF.CGM.getLangOpts().OpenMPIRBuilder)
2402 Addr = CodeGenFunction::OMPBuilderCBHelpers::getAddrOfThreadPrivate(
2403 CGF, VD, Addr, Loc);
2406 CGF.CGM.getOpenMPRuntime().getAddrOfThreadPrivate(CGF, VD, Addr, Loc);
2408 Addr = CGF.Builder.CreateElementBitCast(Addr, RealVarTy);
2409 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2412 static Address emitDeclTargetVarDeclLValue(CodeGenFunction &CGF,
2413 const VarDecl *VD, QualType T) {
2414 llvm::Optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res =
2415 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD);
2416 // Return an invalid address if variable is MT_To and unified
2417 // memory is not enabled. For all other cases: MT_Link and
2418 // MT_To with unified memory, return a valid address.
2419 if (!Res || (*Res == OMPDeclareTargetDeclAttr::MT_To &&
2420 !CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory()))
2421 return Address::invalid();
2422 assert(((*Res == OMPDeclareTargetDeclAttr::MT_Link) ||
2423 (*Res == OMPDeclareTargetDeclAttr::MT_To &&
2424 CGF.CGM.getOpenMPRuntime().hasRequiresUnifiedSharedMemory())) &&
2425 "Expected link clause OR to clause with unified memory enabled.");
2426 QualType PtrTy = CGF.getContext().getPointerType(VD->getType());
2427 Address Addr = CGF.CGM.getOpenMPRuntime().getAddrOfDeclareTargetVar(VD);
2428 return CGF.EmitLoadOfPointer(Addr, PtrTy->castAs<PointerType>());
2432 CodeGenFunction::EmitLoadOfReference(LValue RefLVal,
2433 LValueBaseInfo *PointeeBaseInfo,
2434 TBAAAccessInfo *PointeeTBAAInfo) {
2435 llvm::LoadInst *Load =
2436 Builder.CreateLoad(RefLVal.getAddress(*this), RefLVal.isVolatile());
2437 CGM.DecorateInstructionWithTBAA(Load, RefLVal.getTBAAInfo());
2439 CharUnits Align = CGM.getNaturalTypeAlignment(
2440 RefLVal.getType()->getPointeeType(), PointeeBaseInfo, PointeeTBAAInfo,
2441 /* forPointeeType= */ true);
2442 return Address(Load, Align);
2445 LValue CodeGenFunction::EmitLoadOfReferenceLValue(LValue RefLVal) {
2446 LValueBaseInfo PointeeBaseInfo;
2447 TBAAAccessInfo PointeeTBAAInfo;
2448 Address PointeeAddr = EmitLoadOfReference(RefLVal, &PointeeBaseInfo,
2450 return MakeAddrLValue(PointeeAddr, RefLVal.getType()->getPointeeType(),
2451 PointeeBaseInfo, PointeeTBAAInfo);
2454 Address CodeGenFunction::EmitLoadOfPointer(Address Ptr,
2455 const PointerType *PtrTy,
2456 LValueBaseInfo *BaseInfo,
2457 TBAAAccessInfo *TBAAInfo) {
2458 llvm::Value *Addr = Builder.CreateLoad(Ptr);
2459 return Address(Addr, CGM.getNaturalTypeAlignment(PtrTy->getPointeeType(),
2461 /*forPointeeType=*/true));
2464 LValue CodeGenFunction::EmitLoadOfPointerLValue(Address PtrAddr,
2465 const PointerType *PtrTy) {
2466 LValueBaseInfo BaseInfo;
2467 TBAAAccessInfo TBAAInfo;
2468 Address Addr = EmitLoadOfPointer(PtrAddr, PtrTy, &BaseInfo, &TBAAInfo);
2469 return MakeAddrLValue(Addr, PtrTy->getPointeeType(), BaseInfo, TBAAInfo);
2472 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
2473 const Expr *E, const VarDecl *VD) {
2474 QualType T = E->getType();
2476 // If it's thread_local, emit a call to its wrapper function instead.
2477 if (VD->getTLSKind() == VarDecl::TLS_Dynamic &&
2478 CGF.CGM.getCXXABI().usesThreadWrapperFunction(VD))
2479 return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T);
2480 // Check if the variable is marked as declare target with link clause in
2482 if (CGF.getLangOpts().OpenMPIsDevice) {
2483 Address Addr = emitDeclTargetVarDeclLValue(CGF, VD, T);
2485 return CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2488 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
2489 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType());
2490 V = EmitBitCastOfLValueToProperType(CGF, V, RealVarTy);
2491 CharUnits Alignment = CGF.getContext().getDeclAlign(VD);
2492 Address Addr(V, Alignment);
2493 // Emit reference to the private copy of the variable if it is an OpenMP
2494 // threadprivate variable.
2495 if (CGF.getLangOpts().OpenMP && !CGF.getLangOpts().OpenMPSimd &&
2496 VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2497 return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy,
2500 LValue LV = VD->getType()->isReferenceType() ?
2501 CGF.EmitLoadOfReferenceLValue(Addr, VD->getType(),
2502 AlignmentSource::Decl) :
2503 CGF.MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2504 setObjCGCLValueClass(CGF.getContext(), E, LV);
2508 static llvm::Constant *EmitFunctionDeclPointer(CodeGenModule &CGM,
2510 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
2511 if (FD->hasAttr<WeakRefAttr>()) {
2512 ConstantAddress aliasee = CGM.GetWeakRefReference(FD);
2513 return aliasee.getPointer();
2516 llvm::Constant *V = CGM.GetAddrOfFunction(GD);
2517 if (!FD->hasPrototype()) {
2518 if (const FunctionProtoType *Proto =
2519 FD->getType()->getAs<FunctionProtoType>()) {
2520 // Ugly case: for a K&R-style definition, the type of the definition
2521 // isn't the same as the type of a use. Correct for this with a
2523 QualType NoProtoType =
2524 CGM.getContext().getFunctionNoProtoType(Proto->getReturnType());
2525 NoProtoType = CGM.getContext().getPointerType(NoProtoType);
2526 V = llvm::ConstantExpr::getBitCast(V,
2527 CGM.getTypes().ConvertType(NoProtoType));
2533 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF, const Expr *E,
2535 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
2536 llvm::Value *V = EmitFunctionDeclPointer(CGF.CGM, GD);
2537 CharUnits Alignment = CGF.getContext().getDeclAlign(FD);
2538 return CGF.MakeAddrLValue(V, E->getType(), Alignment,
2539 AlignmentSource::Decl);
2542 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD,
2543 llvm::Value *ThisValue) {
2544 QualType TagType = CGF.getContext().getTagDeclType(FD->getParent());
2545 LValue LV = CGF.MakeNaturalAlignAddrLValue(ThisValue, TagType);
2546 return CGF.EmitLValueForField(LV, FD);
2549 /// Named Registers are named metadata pointing to the register name
2550 /// which will be read from/written to as an argument to the intrinsic
2551 /// @llvm.read/write_register.
2552 /// So far, only the name is being passed down, but other options such as
2553 /// register type, allocation type or even optimization options could be
2554 /// passed down via the metadata node.
2555 static LValue EmitGlobalNamedRegister(const VarDecl *VD, CodeGenModule &CGM) {
2556 SmallString<64> Name("llvm.named.register.");
2557 AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>();
2558 assert(Asm->getLabel().size() < 64-Name.size() &&
2559 "Register name too big");
2560 Name.append(Asm->getLabel());
2561 llvm::NamedMDNode *M =
2562 CGM.getModule().getOrInsertNamedMetadata(Name);
2563 if (M->getNumOperands() == 0) {
2564 llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(),
2566 llvm::Metadata *Ops[] = {Str};
2567 M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
2570 CharUnits Alignment = CGM.getContext().getDeclAlign(VD);
2573 llvm::MetadataAsValue::get(CGM.getLLVMContext(), M->getOperand(0));
2574 return LValue::MakeGlobalReg(Address(Ptr, Alignment), VD->getType());
2577 /// Determine whether we can emit a reference to \p VD from the current
2578 /// context, despite not necessarily having seen an odr-use of the variable in
2580 static bool canEmitSpuriousReferenceToVariable(CodeGenFunction &CGF,
2581 const DeclRefExpr *E,
2584 // For a variable declared in an enclosing scope, do not emit a spurious
2585 // reference even if we have a capture, as that will emit an unwarranted
2586 // reference to our capture state, and will likely generate worse code than
2587 // emitting a local copy.
2588 if (E->refersToEnclosingVariableOrCapture())
2591 // For a local declaration declared in this function, we can always reference
2592 // it even if we don't have an odr-use.
2593 if (VD->hasLocalStorage()) {
2594 return VD->getDeclContext() ==
2595 dyn_cast_or_null<DeclContext>(CGF.CurCodeDecl);
2598 // For a global declaration, we can emit a reference to it if we know
2599 // for sure that we are able to emit a definition of it.
2600 VD = VD->getDefinition(CGF.getContext());
2604 // Don't emit a spurious reference if it might be to a variable that only
2605 // exists on a different device / target.
2606 // FIXME: This is unnecessarily broad. Check whether this would actually be a
2607 // cross-target reference.
2608 if (CGF.getLangOpts().OpenMP || CGF.getLangOpts().CUDA ||
2609 CGF.getLangOpts().OpenCL) {
2613 // We can emit a spurious reference only if the linkage implies that we'll
2614 // be emitting a non-interposable symbol that will be retained until link
2616 switch (CGF.CGM.getLLVMLinkageVarDefinition(VD, IsConstant)) {
2617 case llvm::GlobalValue::ExternalLinkage:
2618 case llvm::GlobalValue::LinkOnceODRLinkage:
2619 case llvm::GlobalValue::WeakODRLinkage:
2620 case llvm::GlobalValue::InternalLinkage:
2621 case llvm::GlobalValue::PrivateLinkage:
2628 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
2629 const NamedDecl *ND = E->getDecl();
2630 QualType T = E->getType();
2632 assert(E->isNonOdrUse() != NOUR_Unevaluated &&
2633 "should not emit an unevaluated operand");
2635 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2636 // Global Named registers access via intrinsics only
2637 if (VD->getStorageClass() == SC_Register &&
2638 VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl())
2639 return EmitGlobalNamedRegister(VD, CGM);
2641 // If this DeclRefExpr does not constitute an odr-use of the variable,
2642 // we're not permitted to emit a reference to it in general, and it might
2643 // not be captured if capture would be necessary for a use. Emit the
2644 // constant value directly instead.
2645 if (E->isNonOdrUse() == NOUR_Constant &&
2646 (VD->getType()->isReferenceType() ||
2647 !canEmitSpuriousReferenceToVariable(*this, E, VD, true))) {
2648 VD->getAnyInitializer(VD);
2649 llvm::Constant *Val = ConstantEmitter(*this).emitAbstract(
2650 E->getLocation(), *VD->evaluateValue(), VD->getType());
2651 assert(Val && "failed to emit constant expression");
2653 Address Addr = Address::invalid();
2654 if (!VD->getType()->isReferenceType()) {
2655 // Spill the constant value to a global.
2656 Addr = CGM.createUnnamedGlobalFrom(*VD, Val,
2657 getContext().getDeclAlign(VD));
2658 llvm::Type *VarTy = getTypes().ConvertTypeForMem(VD->getType());
2659 auto *PTy = llvm::PointerType::get(
2660 VarTy, getContext().getTargetAddressSpace(VD->getType()));
2661 if (PTy != Addr.getType())
2662 Addr = Builder.CreatePointerBitCastOrAddrSpaceCast(Addr, PTy);
2664 // Should we be using the alignment of the constant pointer we emitted?
2665 CharUnits Alignment =
2666 CGM.getNaturalTypeAlignment(E->getType(),
2667 /* BaseInfo= */ nullptr,
2668 /* TBAAInfo= */ nullptr,
2669 /* forPointeeType= */ true);
2670 Addr = Address(Val, Alignment);
2672 return MakeAddrLValue(Addr, T, AlignmentSource::Decl);
2675 // FIXME: Handle other kinds of non-odr-use DeclRefExprs.
2677 // Check for captured variables.
2678 if (E->refersToEnclosingVariableOrCapture()) {
2679 VD = VD->getCanonicalDecl();
2680 if (auto *FD = LambdaCaptureFields.lookup(VD))
2681 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue);
2682 if (CapturedStmtInfo) {
2683 auto I = LocalDeclMap.find(VD);
2684 if (I != LocalDeclMap.end()) {
2686 if (VD->getType()->isReferenceType())
2687 CapLVal = EmitLoadOfReferenceLValue(I->second, VD->getType(),
2688 AlignmentSource::Decl);
2690 CapLVal = MakeAddrLValue(I->second, T);
2691 // Mark lvalue as nontemporal if the variable is marked as nontemporal
2693 if (getLangOpts().OpenMP &&
2694 CGM.getOpenMPRuntime().isNontemporalDecl(VD))
2695 CapLVal.setNontemporal(/*Value=*/true);
2699 EmitCapturedFieldLValue(*this, CapturedStmtInfo->lookup(VD),
2700 CapturedStmtInfo->getContextValue());
2701 CapLVal = MakeAddrLValue(
2702 Address(CapLVal.getPointer(*this), getContext().getDeclAlign(VD)),
2703 CapLVal.getType(), LValueBaseInfo(AlignmentSource::Decl),
2704 CapLVal.getTBAAInfo());
2705 // Mark lvalue as nontemporal if the variable is marked as nontemporal
2707 if (getLangOpts().OpenMP &&
2708 CGM.getOpenMPRuntime().isNontemporalDecl(VD))
2709 CapLVal.setNontemporal(/*Value=*/true);
2713 assert(isa<BlockDecl>(CurCodeDecl));
2714 Address addr = GetAddrOfBlockDecl(VD);
2715 return MakeAddrLValue(addr, T, AlignmentSource::Decl);
2719 // FIXME: We should be able to assert this for FunctionDecls as well!
2720 // FIXME: We should be able to assert this for all DeclRefExprs, not just
2721 // those with a valid source location.
2722 assert((ND->isUsed(false) || !isa<VarDecl>(ND) || E->isNonOdrUse() ||
2723 !E->getLocation().isValid()) &&
2724 "Should not use decl without marking it used!");
2726 if (ND->hasAttr<WeakRefAttr>()) {
2727 const auto *VD = cast<ValueDecl>(ND);
2728 ConstantAddress Aliasee = CGM.GetWeakRefReference(VD);
2729 return MakeAddrLValue(Aliasee, T, AlignmentSource::Decl);
2732 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2733 // Check if this is a global variable.
2734 if (VD->hasLinkage() || VD->isStaticDataMember())
2735 return EmitGlobalVarDeclLValue(*this, E, VD);
2737 Address addr = Address::invalid();
2739 // The variable should generally be present in the local decl map.
2740 auto iter = LocalDeclMap.find(VD);
2741 if (iter != LocalDeclMap.end()) {
2742 addr = iter->second;
2744 // Otherwise, it might be static local we haven't emitted yet for
2745 // some reason; most likely, because it's in an outer function.
2746 } else if (VD->isStaticLocal()) {
2747 addr = Address(CGM.getOrCreateStaticVarDecl(
2748 *VD, CGM.getLLVMLinkageVarDefinition(VD, /*IsConstant=*/false)),
2749 getContext().getDeclAlign(VD));
2751 // No other cases for now.
2753 llvm_unreachable("DeclRefExpr for Decl not entered in LocalDeclMap?");
2757 // Check for OpenMP threadprivate variables.
2758 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd &&
2759 VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2760 return EmitThreadPrivateVarDeclLValue(
2761 *this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()),
2765 // Drill into block byref variables.
2766 bool isBlockByref = VD->isEscapingByref();
2768 addr = emitBlockByrefAddress(addr, VD);
2771 // Drill into reference types.
2772 LValue LV = VD->getType()->isReferenceType() ?
2773 EmitLoadOfReferenceLValue(addr, VD->getType(), AlignmentSource::Decl) :
2774 MakeAddrLValue(addr, T, AlignmentSource::Decl);
2776 bool isLocalStorage = VD->hasLocalStorage();
2778 bool NonGCable = isLocalStorage &&
2779 !VD->getType()->isReferenceType() &&
2782 LV.getQuals().removeObjCGCAttr();
2786 bool isImpreciseLifetime =
2787 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>());
2788 if (isImpreciseLifetime)
2789 LV.setARCPreciseLifetime(ARCImpreciseLifetime);
2790 setObjCGCLValueClass(getContext(), E, LV);
2794 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
2795 return EmitFunctionDeclLValue(*this, E, FD);
2797 // FIXME: While we're emitting a binding from an enclosing scope, all other
2798 // DeclRefExprs we see should be implicitly treated as if they also refer to
2799 // an enclosing scope.
2800 if (const auto *BD = dyn_cast<BindingDecl>(ND))
2801 return EmitLValue(BD->getBinding());
2803 // We can form DeclRefExprs naming GUID declarations when reconstituting
2804 // non-type template parameters into expressions.
2805 if (const auto *GD = dyn_cast<MSGuidDecl>(ND))
2806 return MakeAddrLValue(CGM.GetAddrOfMSGuidDecl(GD), T,
2807 AlignmentSource::Decl);
2809 llvm_unreachable("Unhandled DeclRefExpr");
2812 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
2813 // __extension__ doesn't affect lvalue-ness.
2814 if (E->getOpcode() == UO_Extension)
2815 return EmitLValue(E->getSubExpr());
2817 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
2818 switch (E->getOpcode()) {
2819 default: llvm_unreachable("Unknown unary operator lvalue!");
2821 QualType T = E->getSubExpr()->getType()->getPointeeType();
2822 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
2824 LValueBaseInfo BaseInfo;
2825 TBAAAccessInfo TBAAInfo;
2826 Address Addr = EmitPointerWithAlignment(E->getSubExpr(), &BaseInfo,
2828 LValue LV = MakeAddrLValue(Addr, T, BaseInfo, TBAAInfo);
2829 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
2831 // We should not generate __weak write barrier on indirect reference
2832 // of a pointer to object; as in void foo (__weak id *param); *param = 0;
2833 // But, we continue to generate __strong write barrier on indirect write
2834 // into a pointer to object.
2835 if (getLangOpts().ObjC &&
2836 getLangOpts().getGC() != LangOptions::NonGC &&
2838 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
2843 LValue LV = EmitLValue(E->getSubExpr());
2844 assert(LV.isSimple() && "real/imag on non-ordinary l-value");
2846 // __real is valid on scalars. This is a faster way of testing that.
2847 // __imag can only produce an rvalue on scalars.
2848 if (E->getOpcode() == UO_Real &&
2849 !LV.getAddress(*this).getElementType()->isStructTy()) {
2850 assert(E->getSubExpr()->getType()->isArithmeticType());
2854 QualType T = ExprTy->castAs<ComplexType>()->getElementType();
2857 (E->getOpcode() == UO_Real
2858 ? emitAddrOfRealComponent(LV.getAddress(*this), LV.getType())
2859 : emitAddrOfImagComponent(LV.getAddress(*this), LV.getType()));
2860 LValue ElemLV = MakeAddrLValue(Component, T, LV.getBaseInfo(),
2861 CGM.getTBAAInfoForSubobject(LV, T));
2862 ElemLV.getQuals().addQualifiers(LV.getQuals());
2867 LValue LV = EmitLValue(E->getSubExpr());
2868 bool isInc = E->getOpcode() == UO_PreInc;
2870 if (E->getType()->isAnyComplexType())
2871 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
2873 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
2879 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
2880 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
2881 E->getType(), AlignmentSource::Decl);
2884 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
2885 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
2886 E->getType(), AlignmentSource::Decl);
2889 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
2890 auto SL = E->getFunctionName();
2891 assert(SL != nullptr && "No StringLiteral name in PredefinedExpr");
2892 StringRef FnName = CurFn->getName();
2893 if (FnName.startswith("\01"))
2894 FnName = FnName.substr(1);
2895 StringRef NameItems[] = {
2896 PredefinedExpr::getIdentKindName(E->getIdentKind()), FnName};
2897 std::string GVName = llvm::join(NameItems, NameItems + 2, ".");
2898 if (auto *BD = dyn_cast_or_null<BlockDecl>(CurCodeDecl)) {
2899 std::string Name = std::string(SL->getString());
2900 if (!Name.empty()) {
2901 unsigned Discriminator =
2902 CGM.getCXXABI().getMangleContext().getBlockId(BD, true);
2904 Name += "_" + Twine(Discriminator + 1).str();
2905 auto C = CGM.GetAddrOfConstantCString(Name, GVName.c_str());
2906 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2909 CGM.GetAddrOfConstantCString(std::string(FnName), GVName.c_str());
2910 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2913 auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName);
2914 return MakeAddrLValue(C, E->getType(), AlignmentSource::Decl);
2917 /// Emit a type description suitable for use by a runtime sanitizer library. The
2918 /// format of a type descriptor is
2921 /// { i16 TypeKind, i16 TypeInfo }
2924 /// followed by an array of i8 containing the type name. TypeKind is 0 for an
2925 /// integer, 1 for a floating point value, and -1 for anything else.
2926 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) {
2927 // Only emit each type's descriptor once.
2928 if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T))
2931 uint16_t TypeKind = -1;
2932 uint16_t TypeInfo = 0;
2934 if (T->isIntegerType()) {
2936 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) |
2937 (T->isSignedIntegerType() ? 1 : 0);
2938 } else if (T->isFloatingType()) {
2940 TypeInfo = getContext().getTypeSize(T);
2943 // Format the type name as if for a diagnostic, including quotes and
2944 // optionally an 'aka'.
2945 SmallString<32> Buffer;
2946 CGM.getDiags().ConvertArgToString(DiagnosticsEngine::ak_qualtype,
2947 (intptr_t)T.getAsOpaquePtr(),
2948 StringRef(), StringRef(), None, Buffer,
2951 llvm::Constant *Components[] = {
2952 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo),
2953 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer)
2955 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components);
2957 auto *GV = new llvm::GlobalVariable(
2958 CGM.getModule(), Descriptor->getType(),
2959 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor);
2960 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2961 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(GV);
2963 // Remember the descriptor for this type.
2964 CGM.setTypeDescriptorInMap(T, GV);
2969 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) {
2970 llvm::Type *TargetTy = IntPtrTy;
2972 if (V->getType() == TargetTy)
2975 // Floating-point types which fit into intptr_t are bitcast to integers
2976 // and then passed directly (after zero-extension, if necessary).
2977 if (V->getType()->isFloatingPointTy()) {
2978 unsigned Bits = V->getType()->getPrimitiveSizeInBits();
2979 if (Bits <= TargetTy->getIntegerBitWidth())
2980 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(),
2984 // Integers which fit in intptr_t are zero-extended and passed directly.
2985 if (V->getType()->isIntegerTy() &&
2986 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth())
2987 return Builder.CreateZExt(V, TargetTy);
2989 // Pointers are passed directly, everything else is passed by address.
2990 if (!V->getType()->isPointerTy()) {
2991 Address Ptr = CreateDefaultAlignTempAlloca(V->getType());
2992 Builder.CreateStore(V, Ptr);
2993 V = Ptr.getPointer();
2995 return Builder.CreatePtrToInt(V, TargetTy);
2998 /// Emit a representation of a SourceLocation for passing to a handler
2999 /// in a sanitizer runtime library. The format for this data is:
3001 /// struct SourceLocation {
3002 /// const char *Filename;
3003 /// int32_t Line, Column;
3006 /// For an invalid SourceLocation, the Filename pointer is null.
3007 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
3008 llvm::Constant *Filename;
3011 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc);
3012 if (PLoc.isValid()) {
3013 StringRef FilenameString = PLoc.getFilename();
3015 int PathComponentsToStrip =
3016 CGM.getCodeGenOpts().EmitCheckPathComponentsToStrip;
3017 if (PathComponentsToStrip < 0) {
3018 assert(PathComponentsToStrip != INT_MIN);
3019 int PathComponentsToKeep = -PathComponentsToStrip;
3020 auto I = llvm::sys::path::rbegin(FilenameString);
3021 auto E = llvm::sys::path::rend(FilenameString);
3022 while (I != E && --PathComponentsToKeep)
3025 FilenameString = FilenameString.substr(I - E);
3026 } else if (PathComponentsToStrip > 0) {
3027 auto I = llvm::sys::path::begin(FilenameString);
3028 auto E = llvm::sys::path::end(FilenameString);
3029 while (I != E && PathComponentsToStrip--)
3034 FilenameString.substr(I - llvm::sys::path::begin(FilenameString));
3036 FilenameString = llvm::sys::path::filename(FilenameString);
3040 CGM.GetAddrOfConstantCString(std::string(FilenameString), ".src");
3041 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(
3042 cast<llvm::GlobalVariable>(FilenameGV.getPointer()));
3043 Filename = FilenameGV.getPointer();
3044 Line = PLoc.getLine();
3045 Column = PLoc.getColumn();
3047 Filename = llvm::Constant::getNullValue(Int8PtrTy);
3051 llvm::Constant *Data[] = {Filename, Builder.getInt32(Line),
3052 Builder.getInt32(Column)};
3054 return llvm::ConstantStruct::getAnon(Data);
3058 /// Specify under what conditions this check can be recovered
3059 enum class CheckRecoverableKind {
3060 /// Always terminate program execution if this check fails.
3062 /// Check supports recovering, runtime has both fatal (noreturn) and
3063 /// non-fatal handlers for this check.
3065 /// Runtime conditionally aborts, always need to support recovery.
3070 static CheckRecoverableKind getRecoverableKind(SanitizerMask Kind) {
3071 assert(Kind.countPopulation() == 1);
3072 if (Kind == SanitizerKind::Function || Kind == SanitizerKind::Vptr)
3073 return CheckRecoverableKind::AlwaysRecoverable;
3074 else if (Kind == SanitizerKind::Return || Kind == SanitizerKind::Unreachable)
3075 return CheckRecoverableKind::Unrecoverable;
3077 return CheckRecoverableKind::Recoverable;
3081 struct SanitizerHandlerInfo {
3082 char const *const Name;
3087 const SanitizerHandlerInfo SanitizerHandlers[] = {
3088 #define SANITIZER_CHECK(Enum, Name, Version) {#Name, Version},
3089 LIST_SANITIZER_CHECKS
3090 #undef SANITIZER_CHECK
3093 static void emitCheckHandlerCall(CodeGenFunction &CGF,
3094 llvm::FunctionType *FnType,
3095 ArrayRef<llvm::Value *> FnArgs,
3096 SanitizerHandler CheckHandler,
3097 CheckRecoverableKind RecoverKind, bool IsFatal,
3098 llvm::BasicBlock *ContBB) {
3099 assert(IsFatal || RecoverKind != CheckRecoverableKind::Unrecoverable);
3100 Optional<ApplyDebugLocation> DL;
3101 if (!CGF.Builder.getCurrentDebugLocation()) {
3102 // Ensure that the call has at least an artificial debug location.
3103 DL.emplace(CGF, SourceLocation());
3105 bool NeedsAbortSuffix =
3106 IsFatal && RecoverKind != CheckRecoverableKind::Unrecoverable;
3107 bool MinimalRuntime = CGF.CGM.getCodeGenOpts().SanitizeMinimalRuntime;
3108 const SanitizerHandlerInfo &CheckInfo = SanitizerHandlers[CheckHandler];
3109 const StringRef CheckName = CheckInfo.Name;
3110 std::string FnName = "__ubsan_handle_" + CheckName.str();
3111 if (CheckInfo.Version && !MinimalRuntime)
3112 FnName += "_v" + llvm::utostr(CheckInfo.Version);
3114 FnName += "_minimal";
3115 if (NeedsAbortSuffix)
3118 !IsFatal || RecoverKind == CheckRecoverableKind::AlwaysRecoverable;
3120 llvm::AttrBuilder B;
3122 B.addAttribute(llvm::Attribute::NoReturn)
3123 .addAttribute(llvm::Attribute::NoUnwind);
3125 B.addAttribute(llvm::Attribute::UWTable);
3127 llvm::FunctionCallee Fn = CGF.CGM.CreateRuntimeFunction(
3129 llvm::AttributeList::get(CGF.getLLVMContext(),
3130 llvm::AttributeList::FunctionIndex, B),
3132 llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs);
3134 HandlerCall->setDoesNotReturn();
3135 CGF.Builder.CreateUnreachable();
3137 CGF.Builder.CreateBr(ContBB);
3141 void CodeGenFunction::EmitCheck(
3142 ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
3143 SanitizerHandler CheckHandler, ArrayRef<llvm::Constant *> StaticArgs,
3144 ArrayRef<llvm::Value *> DynamicArgs) {
3145 assert(IsSanitizerScope);
3146 assert(Checked.size() > 0);
3147 assert(CheckHandler >= 0 &&
3148 size_t(CheckHandler) < llvm::array_lengthof(SanitizerHandlers));
3149 const StringRef CheckName = SanitizerHandlers[CheckHandler].Name;
3151 llvm::Value *FatalCond = nullptr;
3152 llvm::Value *RecoverableCond = nullptr;
3153 llvm::Value *TrapCond = nullptr;
3154 for (int i = 0, n = Checked.size(); i < n; ++i) {
3155 llvm::Value *Check = Checked[i].first;
3156 // -fsanitize-trap= overrides -fsanitize-recover=.
3157 llvm::Value *&Cond =
3158 CGM.getCodeGenOpts().SanitizeTrap.has(Checked[i].second)
3160 : CGM.getCodeGenOpts().SanitizeRecover.has(Checked[i].second)
3163 Cond = Cond ? Builder.CreateAnd(Cond, Check) : Check;
3167 EmitTrapCheck(TrapCond);
3168 if (!FatalCond && !RecoverableCond)
3171 llvm::Value *JointCond;
3172 if (FatalCond && RecoverableCond)
3173 JointCond = Builder.CreateAnd(FatalCond, RecoverableCond);
3175 JointCond = FatalCond ? FatalCond : RecoverableCond;
3178 CheckRecoverableKind RecoverKind = getRecoverableKind(Checked[0].second);
3179 assert(SanOpts.has(Checked[0].second));
3181 for (int i = 1, n = Checked.size(); i < n; ++i) {
3182 assert(RecoverKind == getRecoverableKind(Checked[i].second) &&
3183 "All recoverable kinds in a single check must be same!");
3184 assert(SanOpts.has(Checked[i].second));
3188 llvm::BasicBlock *Cont = createBasicBlock("cont");
3189 llvm::BasicBlock *Handlers = createBasicBlock("handler." + CheckName);
3190 llvm::Instruction *Branch = Builder.CreateCondBr(JointCond, Cont, Handlers);
3191 // Give hint that we very much don't expect to execute the handler
3192 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
3193 llvm::MDBuilder MDHelper(getLLVMContext());
3194 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
3195 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node);
3196 EmitBlock(Handlers);
3198 // Handler functions take an i8* pointing to the (handler-specific) static
3199 // information block, followed by a sequence of intptr_t arguments
3200 // representing operand values.
3201 SmallVector<llvm::Value *, 4> Args;
3202 SmallVector<llvm::Type *, 4> ArgTypes;
3203 if (!CGM.getCodeGenOpts().SanitizeMinimalRuntime) {
3204 Args.reserve(DynamicArgs.size() + 1);
3205 ArgTypes.reserve(DynamicArgs.size() + 1);
3207 // Emit handler arguments and create handler function type.
3208 if (!StaticArgs.empty()) {
3209 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
3211 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
3212 llvm::GlobalVariable::PrivateLinkage, Info);
3213 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3214 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
3215 Args.push_back(Builder.CreateBitCast(InfoPtr, Int8PtrTy));
3216 ArgTypes.push_back(Int8PtrTy);
3219 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) {
3220 Args.push_back(EmitCheckValue(DynamicArgs[i]));
3221 ArgTypes.push_back(IntPtrTy);
3225 llvm::FunctionType *FnType =
3226 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false);
3228 if (!FatalCond || !RecoverableCond) {
3229 // Simple case: we need to generate a single handler call, either
3230 // fatal, or non-fatal.
3231 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind,
3232 (FatalCond != nullptr), Cont);
3234 // Emit two handler calls: first one for set of unrecoverable checks,
3235 // another one for recoverable.
3236 llvm::BasicBlock *NonFatalHandlerBB =
3237 createBasicBlock("non_fatal." + CheckName);
3238 llvm::BasicBlock *FatalHandlerBB = createBasicBlock("fatal." + CheckName);
3239 Builder.CreateCondBr(FatalCond, NonFatalHandlerBB, FatalHandlerBB);
3240 EmitBlock(FatalHandlerBB);
3241 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, true,
3243 EmitBlock(NonFatalHandlerBB);
3244 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, false,
3251 void CodeGenFunction::EmitCfiSlowPathCheck(
3252 SanitizerMask Kind, llvm::Value *Cond, llvm::ConstantInt *TypeId,
3253 llvm::Value *Ptr, ArrayRef<llvm::Constant *> StaticArgs) {
3254 llvm::BasicBlock *Cont = createBasicBlock("cfi.cont");
3256 llvm::BasicBlock *CheckBB = createBasicBlock("cfi.slowpath");
3257 llvm::BranchInst *BI = Builder.CreateCondBr(Cond, Cont, CheckBB);
3259 llvm::MDBuilder MDHelper(getLLVMContext());
3260 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
3261 BI->setMetadata(llvm::LLVMContext::MD_prof, Node);
3265 bool WithDiag = !CGM.getCodeGenOpts().SanitizeTrap.has(Kind);
3267 llvm::CallInst *CheckCall;
3268 llvm::FunctionCallee SlowPathFn;
3270 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
3272 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
3273 llvm::GlobalVariable::PrivateLinkage, Info);
3274 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3275 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
3277 SlowPathFn = CGM.getModule().getOrInsertFunction(
3278 "__cfi_slowpath_diag",
3279 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy},
3281 CheckCall = Builder.CreateCall(
3282 SlowPathFn, {TypeId, Ptr, Builder.CreateBitCast(InfoPtr, Int8PtrTy)});
3284 SlowPathFn = CGM.getModule().getOrInsertFunction(
3286 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy}, false));
3287 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr});
3291 cast<llvm::GlobalValue>(SlowPathFn.getCallee()->stripPointerCasts()));
3292 CheckCall->setDoesNotThrow();
3297 // Emit a stub for __cfi_check function so that the linker knows about this
3298 // symbol in LTO mode.
3299 void CodeGenFunction::EmitCfiCheckStub() {
3300 llvm::Module *M = &CGM.getModule();
3301 auto &Ctx = M->getContext();
3302 llvm::Function *F = llvm::Function::Create(
3303 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, false),
3304 llvm::GlobalValue::WeakAnyLinkage, "__cfi_check", M);
3306 llvm::BasicBlock *BB = llvm::BasicBlock::Create(Ctx, "entry", F);
3307 // FIXME: consider emitting an intrinsic call like
3308 // call void @llvm.cfi_check(i64 %0, i8* %1, i8* %2)
3309 // which can be lowered in CrossDSOCFI pass to the actual contents of
3310 // __cfi_check. This would allow inlining of __cfi_check calls.
3311 llvm::CallInst::Create(
3312 llvm::Intrinsic::getDeclaration(M, llvm::Intrinsic::trap), "", BB);
3313 llvm::ReturnInst::Create(Ctx, nullptr, BB);
3316 // This function is basically a switch over the CFI failure kind, which is
3317 // extracted from CFICheckFailData (1st function argument). Each case is either
3318 // llvm.trap or a call to one of the two runtime handlers, based on
3319 // -fsanitize-trap and -fsanitize-recover settings. Default case (invalid
3320 // failure kind) traps, but this should really never happen. CFICheckFailData
3321 // can be nullptr if the calling module has -fsanitize-trap behavior for this
3322 // check kind; in this case __cfi_check_fail traps as well.
3323 void CodeGenFunction::EmitCfiCheckFail() {
3324 SanitizerScope SanScope(this);
3325 FunctionArgList Args;
3326 ImplicitParamDecl ArgData(getContext(), getContext().VoidPtrTy,
3327 ImplicitParamDecl::Other);
3328 ImplicitParamDecl ArgAddr(getContext(), getContext().VoidPtrTy,
3329 ImplicitParamDecl::Other);
3330 Args.push_back(&ArgData);
3331 Args.push_back(&ArgAddr);
3333 const CGFunctionInfo &FI =
3334 CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, Args);
3336 llvm::Function *F = llvm::Function::Create(
3337 llvm::FunctionType::get(VoidTy, {VoidPtrTy, VoidPtrTy}, false),
3338 llvm::GlobalValue::WeakODRLinkage, "__cfi_check_fail", &CGM.getModule());
3340 CGM.SetLLVMFunctionAttributes(GlobalDecl(), FI, F);
3341 CGM.SetLLVMFunctionAttributesForDefinition(nullptr, F);
3342 F->setVisibility(llvm::GlobalValue::HiddenVisibility);
3344 StartFunction(GlobalDecl(), CGM.getContext().VoidTy, F, FI, Args,
3347 // This function should not be affected by blacklist. This function does
3348 // not have a source location, but "src:*" would still apply. Revert any
3349 // changes to SanOpts made in StartFunction.
3350 SanOpts = CGM.getLangOpts().Sanitize;
3353 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgData), /*Volatile=*/false,
3354 CGM.getContext().VoidPtrTy, ArgData.getLocation());
3356 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgAddr), /*Volatile=*/false,
3357 CGM.getContext().VoidPtrTy, ArgAddr.getLocation());
3359 // Data == nullptr means the calling module has trap behaviour for this check.
3360 llvm::Value *DataIsNotNullPtr =
3361 Builder.CreateICmpNE(Data, llvm::ConstantPointerNull::get(Int8PtrTy));
3362 EmitTrapCheck(DataIsNotNullPtr);
3364 llvm::StructType *SourceLocationTy =
3365 llvm::StructType::get(VoidPtrTy, Int32Ty, Int32Ty);
3366 llvm::StructType *CfiCheckFailDataTy =
3367 llvm::StructType::get(Int8Ty, SourceLocationTy, VoidPtrTy);
3369 llvm::Value *V = Builder.CreateConstGEP2_32(
3371 Builder.CreatePointerCast(Data, CfiCheckFailDataTy->getPointerTo(0)), 0,
3373 Address CheckKindAddr(V, getIntAlign());
3374 llvm::Value *CheckKind = Builder.CreateLoad(CheckKindAddr);
3376 llvm::Value *AllVtables = llvm::MetadataAsValue::get(
3377 CGM.getLLVMContext(),
3378 llvm::MDString::get(CGM.getLLVMContext(), "all-vtables"));
3379 llvm::Value *ValidVtable = Builder.CreateZExt(
3380 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::type_test),
3381 {Addr, AllVtables}),
3384 const std::pair<int, SanitizerMask> CheckKinds[] = {
3385 {CFITCK_VCall, SanitizerKind::CFIVCall},
3386 {CFITCK_NVCall, SanitizerKind::CFINVCall},
3387 {CFITCK_DerivedCast, SanitizerKind::CFIDerivedCast},
3388 {CFITCK_UnrelatedCast, SanitizerKind::CFIUnrelatedCast},
3389 {CFITCK_ICall, SanitizerKind::CFIICall}};
3391 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 5> Checks;
3392 for (auto CheckKindMaskPair : CheckKinds) {
3393 int Kind = CheckKindMaskPair.first;
3394 SanitizerMask Mask = CheckKindMaskPair.second;
3396 Builder.CreateICmpNE(CheckKind, llvm::ConstantInt::get(Int8Ty, Kind));
3397 if (CGM.getLangOpts().Sanitize.has(Mask))
3398 EmitCheck(std::make_pair(Cond, Mask), SanitizerHandler::CFICheckFail, {},
3399 {Data, Addr, ValidVtable});
3401 EmitTrapCheck(Cond);
3405 // The only reference to this function will be created during LTO link.
3406 // Make sure it survives until then.
3407 CGM.addUsedGlobal(F);
3410 void CodeGenFunction::EmitUnreachable(SourceLocation Loc) {
3411 if (SanOpts.has(SanitizerKind::Unreachable)) {
3412 SanitizerScope SanScope(this);
3413 EmitCheck(std::make_pair(static_cast<llvm::Value *>(Builder.getFalse()),
3414 SanitizerKind::Unreachable),
3415 SanitizerHandler::BuiltinUnreachable,
3416 EmitCheckSourceLocation(Loc), None);
3418 Builder.CreateUnreachable();
3421 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked) {
3422 llvm::BasicBlock *Cont = createBasicBlock("cont");
3424 // If we're optimizing, collapse all calls to trap down to just one per
3425 // function to save on code size.
3426 if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB) {
3427 TrapBB = createBasicBlock("trap");
3428 Builder.CreateCondBr(Checked, Cont, TrapBB);
3430 llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
3431 TrapCall->setDoesNotReturn();
3432 TrapCall->setDoesNotThrow();
3433 Builder.CreateUnreachable();
3435 Builder.CreateCondBr(Checked, Cont, TrapBB);
3441 llvm::CallInst *CodeGenFunction::EmitTrapCall(llvm::Intrinsic::ID IntrID) {
3442 llvm::CallInst *TrapCall = Builder.CreateCall(CGM.getIntrinsic(IntrID));
3444 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) {
3445 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name",
3446 CGM.getCodeGenOpts().TrapFuncName);
3447 TrapCall->addAttribute(llvm::AttributeList::FunctionIndex, A);
3453 Address CodeGenFunction::EmitArrayToPointerDecay(const Expr *E,
3454 LValueBaseInfo *BaseInfo,
3455 TBAAAccessInfo *TBAAInfo) {
3456 assert(E->getType()->isArrayType() &&
3457 "Array to pointer decay must have array source type!");
3459 // Expressions of array type can't be bitfields or vector elements.
3460 LValue LV = EmitLValue(E);
3461 Address Addr = LV.getAddress(*this);
3463 // If the array type was an incomplete type, we need to make sure
3464 // the decay ends up being the right type.
3465 llvm::Type *NewTy = ConvertType(E->getType());
3466 Addr = Builder.CreateElementBitCast(Addr, NewTy);
3468 // Note that VLA pointers are always decayed, so we don't need to do
3470 if (!E->getType()->isVariableArrayType()) {
3471 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3472 "Expected pointer to array");
3473 Addr = Builder.CreateConstArrayGEP(Addr, 0, "arraydecay");
3476 // The result of this decay conversion points to an array element within the
3477 // base lvalue. However, since TBAA currently does not support representing
3478 // accesses to elements of member arrays, we conservatively represent accesses
3479 // to the pointee object as if it had no any base lvalue specified.
3480 // TODO: Support TBAA for member arrays.
3481 QualType EltType = E->getType()->castAsArrayTypeUnsafe()->getElementType();
3482 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
3483 if (TBAAInfo) *TBAAInfo = CGM.getTBAAAccessInfo(EltType);
3485 return Builder.CreateElementBitCast(Addr, ConvertTypeForMem(EltType));
3488 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
3489 /// array to pointer, return the array subexpression.
3490 static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
3491 // If this isn't just an array->pointer decay, bail out.
3492 const auto *CE = dyn_cast<CastExpr>(E);
3493 if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay)
3496 // If this is a decay from variable width array, bail out.
3497 const Expr *SubExpr = CE->getSubExpr();
3498 if (SubExpr->getType()->isVariableArrayType())
3504 static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF,
3506 ArrayRef<llvm::Value*> indices,
3510 const llvm::Twine &name = "arrayidx") {
3512 return CGF.EmitCheckedInBoundsGEP(ptr, indices, signedIndices,
3513 CodeGenFunction::NotSubtraction, loc,
3516 return CGF.Builder.CreateGEP(ptr, indices, name);
3520 static CharUnits getArrayElementAlign(CharUnits arrayAlign,
3522 CharUnits eltSize) {
3523 // If we have a constant index, we can use the exact offset of the
3524 // element we're accessing.
3525 if (auto constantIdx = dyn_cast<llvm::ConstantInt>(idx)) {
3526 CharUnits offset = constantIdx->getZExtValue() * eltSize;
3527 return arrayAlign.alignmentAtOffset(offset);
3529 // Otherwise, use the worst-case alignment for any element.
3531 return arrayAlign.alignmentOfArrayElement(eltSize);
3535 static QualType getFixedSizeElementType(const ASTContext &ctx,
3536 const VariableArrayType *vla) {
3539 eltType = vla->getElementType();
3540 } while ((vla = ctx.getAsVariableArrayType(eltType)));
3544 /// Given an array base, check whether its member access belongs to a record
3545 /// with preserve_access_index attribute or not.
3546 static bool IsPreserveAIArrayBase(CodeGenFunction &CGF, const Expr *ArrayBase) {
3547 if (!ArrayBase || !CGF.getDebugInfo())
3550 // Only support base as either a MemberExpr or DeclRefExpr.
3551 // DeclRefExpr to cover cases like:
3552 // struct s { int a; int b[10]; };
3555 // p[1] will generate a DeclRefExpr and p[1].a is a MemberExpr.
3556 // p->b[5] is a MemberExpr example.
3557 const Expr *E = ArrayBase->IgnoreImpCasts();
3558 if (const auto *ME = dyn_cast<MemberExpr>(E))
3559 return ME->getMemberDecl()->hasAttr<BPFPreserveAccessIndexAttr>();
3561 if (const auto *DRE = dyn_cast<DeclRefExpr>(E)) {
3562 const auto *VarDef = dyn_cast<VarDecl>(DRE->getDecl());
3566 const auto *PtrT = VarDef->getType()->getAs<PointerType>();
3570 const auto *PointeeT = PtrT->getPointeeType()
3571 ->getUnqualifiedDesugaredType();
3572 if (const auto *RecT = dyn_cast<RecordType>(PointeeT))
3573 return RecT->getDecl()->hasAttr<BPFPreserveAccessIndexAttr>();
3580 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr,
3581 ArrayRef<llvm::Value *> indices,
3582 QualType eltType, bool inbounds,
3583 bool signedIndices, SourceLocation loc,
3584 QualType *arrayType = nullptr,
3585 const Expr *Base = nullptr,
3586 const llvm::Twine &name = "arrayidx") {
3587 // All the indices except that last must be zero.
3589 for (auto idx : indices.drop_back())
3590 assert(isa<llvm::ConstantInt>(idx) &&
3591 cast<llvm::ConstantInt>(idx)->isZero());
3594 // Determine the element size of the statically-sized base. This is
3595 // the thing that the indices are expressed in terms of.
3596 if (auto vla = CGF.getContext().getAsVariableArrayType(eltType)) {
3597 eltType = getFixedSizeElementType(CGF.getContext(), vla);
3600 // We can use that to compute the best alignment of the element.
3601 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType);
3602 CharUnits eltAlign =
3603 getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize);
3605 llvm::Value *eltPtr;
3606 auto LastIndex = dyn_cast<llvm::ConstantInt>(indices.back());
3608 (!CGF.IsInPreservedAIRegion && !IsPreserveAIArrayBase(CGF, Base))) {
3609 eltPtr = emitArraySubscriptGEP(
3610 CGF, addr.getPointer(), indices, inbounds, signedIndices,
3613 // Remember the original array subscript for bpf target
3614 unsigned idx = LastIndex->getZExtValue();
3615 llvm::DIType *DbgInfo = nullptr;
3617 DbgInfo = CGF.getDebugInfo()->getOrCreateStandaloneType(*arrayType, loc);
3618 eltPtr = CGF.Builder.CreatePreserveArrayAccessIndex(addr.getElementType(),
3624 return Address(eltPtr, eltAlign);
3627 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
3629 // The index must always be an integer, which is not an aggregate. Emit it
3630 // in lexical order (this complexity is, sadly, required by C++17).
3631 llvm::Value *IdxPre =
3632 (E->getLHS() == E->getIdx()) ? EmitScalarExpr(E->getIdx()) : nullptr;
3633 bool SignedIndices = false;
3634 auto EmitIdxAfterBase = [&, IdxPre](bool Promote) -> llvm::Value * {
3636 if (E->getLHS() != E->getIdx()) {
3637 assert(E->getRHS() == E->getIdx() && "index was neither LHS nor RHS");
3638 Idx = EmitScalarExpr(E->getIdx());
3641 QualType IdxTy = E->getIdx()->getType();
3642 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType();
3643 SignedIndices |= IdxSigned;
3645 if (SanOpts.has(SanitizerKind::ArrayBounds))
3646 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed);
3648 // Extend or truncate the index type to 32 or 64-bits.
3649 if (Promote && Idx->getType() != IntPtrTy)
3650 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
3656 // If the base is a vector type, then we are forming a vector element lvalue
3657 // with this subscript.
3658 if (E->getBase()->getType()->isVectorType() &&
3659 !isa<ExtVectorElementExpr>(E->getBase())) {
3660 // Emit the vector as an lvalue to get its address.
3661 LValue LHS = EmitLValue(E->getBase());
3662 auto *Idx = EmitIdxAfterBase(/*Promote*/false);
3663 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
3664 return LValue::MakeVectorElt(LHS.getAddress(*this), Idx,
3665 E->getBase()->getType(), LHS.getBaseInfo(),
3669 // All the other cases basically behave like simple offsetting.
3671 // Handle the extvector case we ignored above.
3672 if (isa<ExtVectorElementExpr>(E->getBase())) {
3673 LValue LV = EmitLValue(E->getBase());
3674 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3675 Address Addr = EmitExtVectorElementLValue(LV);
3677 QualType EltType = LV.getType()->castAs<VectorType>()->getElementType();
3678 Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true,
3679 SignedIndices, E->getExprLoc());
3680 return MakeAddrLValue(Addr, EltType, LV.getBaseInfo(),
3681 CGM.getTBAAInfoForSubobject(LV, EltType));
3684 LValueBaseInfo EltBaseInfo;
3685 TBAAAccessInfo EltTBAAInfo;
3686 Address Addr = Address::invalid();
3687 if (const VariableArrayType *vla =
3688 getContext().getAsVariableArrayType(E->getType())) {
3689 // The base must be a pointer, which is not an aggregate. Emit
3690 // it. It needs to be emitted first in case it's what captures
3692 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3693 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3695 // The element count here is the total number of non-VLA elements.
3696 llvm::Value *numElements = getVLASize(vla).NumElts;
3698 // Effectively, the multiply by the VLA size is part of the GEP.
3699 // GEP indexes are signed, and scaling an index isn't permitted to
3700 // signed-overflow, so we use the same semantics for our explicit
3701 // multiply. We suppress this if overflow is not undefined behavior.
3702 if (getLangOpts().isSignedOverflowDefined()) {
3703 Idx = Builder.CreateMul(Idx, numElements);
3705 Idx = Builder.CreateNSWMul(Idx, numElements);
3708 Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(),
3709 !getLangOpts().isSignedOverflowDefined(),
3710 SignedIndices, E->getExprLoc());
3712 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
3713 // Indexing over an interface, as in "NSString *P; P[4];"
3715 // Emit the base pointer.
3716 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3717 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3719 CharUnits InterfaceSize = getContext().getTypeSizeInChars(OIT);
3720 llvm::Value *InterfaceSizeVal =
3721 llvm::ConstantInt::get(Idx->getType(), InterfaceSize.getQuantity());
3723 llvm::Value *ScaledIdx = Builder.CreateMul(Idx, InterfaceSizeVal);
3725 // We don't necessarily build correct LLVM struct types for ObjC
3726 // interfaces, so we can't rely on GEP to do this scaling
3727 // correctly, so we need to cast to i8*. FIXME: is this actually
3728 // true? A lot of other things in the fragile ABI would break...
3729 llvm::Type *OrigBaseTy = Addr.getType();
3730 Addr = Builder.CreateElementBitCast(Addr, Int8Ty);
3733 CharUnits EltAlign =
3734 getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize);
3735 llvm::Value *EltPtr =
3736 emitArraySubscriptGEP(*this, Addr.getPointer(), ScaledIdx, false,
3737 SignedIndices, E->getExprLoc());
3738 Addr = Address(EltPtr, EltAlign);
3741 Addr = Builder.CreateBitCast(Addr, OrigBaseTy);
3742 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3743 // If this is A[i] where A is an array, the frontend will have decayed the
3744 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3745 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3746 // "gep x, i" here. Emit one "gep A, 0, i".
3747 assert(Array->getType()->isArrayType() &&
3748 "Array to pointer decay must have array source type!");
3750 // For simple multidimensional array indexing, set the 'accessed' flag for
3751 // better bounds-checking of the base expression.
3752 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3753 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3755 ArrayLV = EmitLValue(Array);
3756 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3758 // Propagate the alignment from the array itself to the result.
3759 QualType arrayType = Array->getType();
3760 Addr = emitArraySubscriptGEP(
3761 *this, ArrayLV.getAddress(*this), {CGM.getSize(CharUnits::Zero()), Idx},
3762 E->getType(), !getLangOpts().isSignedOverflowDefined(), SignedIndices,
3763 E->getExprLoc(), &arrayType, E->getBase());
3764 EltBaseInfo = ArrayLV.getBaseInfo();
3765 EltTBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, E->getType());
3767 // The base must be a pointer; emit it with an estimate of its alignment.
3768 Addr = EmitPointerWithAlignment(E->getBase(), &EltBaseInfo, &EltTBAAInfo);
3769 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3770 QualType ptrType = E->getBase()->getType();
3771 Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(),
3772 !getLangOpts().isSignedOverflowDefined(),
3773 SignedIndices, E->getExprLoc(), &ptrType,
3777 LValue LV = MakeAddrLValue(Addr, E->getType(), EltBaseInfo, EltTBAAInfo);
3779 if (getLangOpts().ObjC &&
3780 getLangOpts().getGC() != LangOptions::NonGC) {
3781 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
3782 setObjCGCLValueClass(getContext(), E, LV);
3787 LValue CodeGenFunction::EmitMatrixSubscriptExpr(const MatrixSubscriptExpr *E) {
3789 !E->isIncomplete() &&
3790 "incomplete matrix subscript expressions should be rejected during Sema");
3791 LValue Base = EmitLValue(E->getBase());
3792 llvm::Value *RowIdx = EmitScalarExpr(E->getRowIdx());
3793 llvm::Value *ColIdx = EmitScalarExpr(E->getColumnIdx());
3794 llvm::Value *NumRows = Builder.getIntN(
3795 RowIdx->getType()->getScalarSizeInBits(),
3796 E->getBase()->getType()->getAs<ConstantMatrixType>()->getNumRows());
3797 llvm::Value *FinalIdx =
3798 Builder.CreateAdd(Builder.CreateMul(ColIdx, NumRows), RowIdx);
3799 return LValue::MakeMatrixElt(
3800 MaybeConvertMatrixAddress(Base.getAddress(*this), *this), FinalIdx,
3801 E->getBase()->getType(), Base.getBaseInfo(), TBAAAccessInfo());
3804 static Address emitOMPArraySectionBase(CodeGenFunction &CGF, const Expr *Base,
3805 LValueBaseInfo &BaseInfo,
3806 TBAAAccessInfo &TBAAInfo,
3807 QualType BaseTy, QualType ElTy,
3808 bool IsLowerBound) {
3810 if (auto *ASE = dyn_cast<OMPArraySectionExpr>(Base->IgnoreParenImpCasts())) {
3811 BaseLVal = CGF.EmitOMPArraySectionExpr(ASE, IsLowerBound);
3812 if (BaseTy->isArrayType()) {
3813 Address Addr = BaseLVal.getAddress(CGF);
3814 BaseInfo = BaseLVal.getBaseInfo();
3816 // If the array type was an incomplete type, we need to make sure
3817 // the decay ends up being the right type.
3818 llvm::Type *NewTy = CGF.ConvertType(BaseTy);
3819 Addr = CGF.Builder.CreateElementBitCast(Addr, NewTy);
3821 // Note that VLA pointers are always decayed, so we don't need to do
3823 if (!BaseTy->isVariableArrayType()) {
3824 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3825 "Expected pointer to array");
3826 Addr = CGF.Builder.CreateConstArrayGEP(Addr, 0, "arraydecay");
3829 return CGF.Builder.CreateElementBitCast(Addr,
3830 CGF.ConvertTypeForMem(ElTy));
3832 LValueBaseInfo TypeBaseInfo;
3833 TBAAAccessInfo TypeTBAAInfo;
3835 CGF.CGM.getNaturalTypeAlignment(ElTy, &TypeBaseInfo, &TypeTBAAInfo);
3836 BaseInfo.mergeForCast(TypeBaseInfo);
3837 TBAAInfo = CGF.CGM.mergeTBAAInfoForCast(TBAAInfo, TypeTBAAInfo);
3838 return Address(CGF.Builder.CreateLoad(BaseLVal.getAddress(CGF)), Align);
3840 return CGF.EmitPointerWithAlignment(Base, &BaseInfo, &TBAAInfo);
3843 LValue CodeGenFunction::EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
3844 bool IsLowerBound) {
3845 QualType BaseTy = OMPArraySectionExpr::getBaseOriginalType(E->getBase());
3846 QualType ResultExprTy;
3847 if (auto *AT = getContext().getAsArrayType(BaseTy))
3848 ResultExprTy = AT->getElementType();
3850 ResultExprTy = BaseTy->getPointeeType();
3851 llvm::Value *Idx = nullptr;
3852 if (IsLowerBound || E->getColonLocFirst().isInvalid()) {
3853 // Requesting lower bound or upper bound, but without provided length and
3854 // without ':' symbol for the default length -> length = 1.
3855 // Idx = LowerBound ?: 0;
3856 if (auto *LowerBound = E->getLowerBound()) {
3857 Idx = Builder.CreateIntCast(
3858 EmitScalarExpr(LowerBound), IntPtrTy,
3859 LowerBound->getType()->hasSignedIntegerRepresentation());
3861 Idx = llvm::ConstantInt::getNullValue(IntPtrTy);
3863 // Try to emit length or lower bound as constant. If this is possible, 1
3864 // is subtracted from constant length or lower bound. Otherwise, emit LLVM
3865 // IR (LB + Len) - 1.
3866 auto &C = CGM.getContext();
3867 auto *Length = E->getLength();
3868 llvm::APSInt ConstLength;
3870 // Idx = LowerBound + Length - 1;
3871 if (Length->isIntegerConstantExpr(ConstLength, C)) {
3872 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3875 auto *LowerBound = E->getLowerBound();
3876 llvm::APSInt ConstLowerBound(PointerWidthInBits, /*isUnsigned=*/false);
3877 if (LowerBound && LowerBound->isIntegerConstantExpr(ConstLowerBound, C)) {
3878 ConstLowerBound = ConstLowerBound.zextOrTrunc(PointerWidthInBits);
3879 LowerBound = nullptr;
3883 else if (!LowerBound)
3886 if (Length || LowerBound) {
3887 auto *LowerBoundVal =
3889 ? Builder.CreateIntCast(
3890 EmitScalarExpr(LowerBound), IntPtrTy,
3891 LowerBound->getType()->hasSignedIntegerRepresentation())
3892 : llvm::ConstantInt::get(IntPtrTy, ConstLowerBound);
3895 ? Builder.CreateIntCast(
3896 EmitScalarExpr(Length), IntPtrTy,
3897 Length->getType()->hasSignedIntegerRepresentation())
3898 : llvm::ConstantInt::get(IntPtrTy, ConstLength);
3899 Idx = Builder.CreateAdd(LowerBoundVal, LengthVal, "lb_add_len",
3901 !getLangOpts().isSignedOverflowDefined());
3902 if (Length && LowerBound) {
3903 Idx = Builder.CreateSub(
3904 Idx, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "idx_sub_1",
3905 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3908 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength + ConstLowerBound);
3910 // Idx = ArraySize - 1;
3911 QualType ArrayTy = BaseTy->isPointerType()
3912 ? E->getBase()->IgnoreParenImpCasts()->getType()
3914 if (auto *VAT = C.getAsVariableArrayType(ArrayTy)) {
3915 Length = VAT->getSizeExpr();
3916 if (Length->isIntegerConstantExpr(ConstLength, C))
3919 auto *CAT = C.getAsConstantArrayType(ArrayTy);
3920 ConstLength = CAT->getSize();
3923 auto *LengthVal = Builder.CreateIntCast(
3924 EmitScalarExpr(Length), IntPtrTy,
3925 Length->getType()->hasSignedIntegerRepresentation());
3926 Idx = Builder.CreateSub(
3927 LengthVal, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "len_sub_1",
3928 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3930 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3932 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength);
3938 Address EltPtr = Address::invalid();
3939 LValueBaseInfo BaseInfo;
3940 TBAAAccessInfo TBAAInfo;
3941 if (auto *VLA = getContext().getAsVariableArrayType(ResultExprTy)) {
3942 // The base must be a pointer, which is not an aggregate. Emit
3943 // it. It needs to be emitted first in case it's what captures
3946 emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, TBAAInfo,
3947 BaseTy, VLA->getElementType(), IsLowerBound);
3948 // The element count here is the total number of non-VLA elements.
3949 llvm::Value *NumElements = getVLASize(VLA).NumElts;
3951 // Effectively, the multiply by the VLA size is part of the GEP.
3952 // GEP indexes are signed, and scaling an index isn't permitted to
3953 // signed-overflow, so we use the same semantics for our explicit
3954 // multiply. We suppress this if overflow is not undefined behavior.
3955 if (getLangOpts().isSignedOverflowDefined())
3956 Idx = Builder.CreateMul(Idx, NumElements);
3958 Idx = Builder.CreateNSWMul(Idx, NumElements);
3959 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(),
3960 !getLangOpts().isSignedOverflowDefined(),
3961 /*signedIndices=*/false, E->getExprLoc());
3962 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3963 // If this is A[i] where A is an array, the frontend will have decayed the
3964 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3965 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3966 // "gep x, i" here. Emit one "gep A, 0, i".
3967 assert(Array->getType()->isArrayType() &&
3968 "Array to pointer decay must have array source type!");
3970 // For simple multidimensional array indexing, set the 'accessed' flag for
3971 // better bounds-checking of the base expression.
3972 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3973 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3975 ArrayLV = EmitLValue(Array);
3977 // Propagate the alignment from the array itself to the result.
3978 EltPtr = emitArraySubscriptGEP(
3979 *this, ArrayLV.getAddress(*this), {CGM.getSize(CharUnits::Zero()), Idx},
3980 ResultExprTy, !getLangOpts().isSignedOverflowDefined(),
3981 /*signedIndices=*/false, E->getExprLoc());
3982 BaseInfo = ArrayLV.getBaseInfo();
3983 TBAAInfo = CGM.getTBAAInfoForSubobject(ArrayLV, ResultExprTy);
3985 Address Base = emitOMPArraySectionBase(*this, E->getBase(), BaseInfo,
3986 TBAAInfo, BaseTy, ResultExprTy,
3988 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy,
3989 !getLangOpts().isSignedOverflowDefined(),
3990 /*signedIndices=*/false, E->getExprLoc());
3993 return MakeAddrLValue(EltPtr, ResultExprTy, BaseInfo, TBAAInfo);
3996 LValue CodeGenFunction::
3997 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
3998 // Emit the base vector as an l-value.
4001 // ExtVectorElementExpr's base can either be a vector or pointer to vector.
4003 // If it is a pointer to a vector, emit the address and form an lvalue with
4005 LValueBaseInfo BaseInfo;
4006 TBAAAccessInfo TBAAInfo;
4007 Address Ptr = EmitPointerWithAlignment(E->getBase(), &BaseInfo, &TBAAInfo);
4008 const auto *PT = E->getBase()->getType()->castAs<PointerType>();
4009 Base = MakeAddrLValue(Ptr, PT->getPointeeType(), BaseInfo, TBAAInfo);
4010 Base.getQuals().removeObjCGCAttr();
4011 } else if (E->getBase()->isGLValue()) {
4012 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
4013 // emit the base as an lvalue.
4014 assert(E->getBase()->getType()->isVectorType());
4015 Base = EmitLValue(E->getBase());
4017 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
4018 assert(E->getBase()->getType()->isVectorType() &&
4019 "Result must be a vector");
4020 llvm::Value *Vec = EmitScalarExpr(E->getBase());
4022 // Store the vector to memory (because LValue wants an address).
4023 Address VecMem = CreateMemTemp(E->getBase()->getType());
4024 Builder.CreateStore(Vec, VecMem);
4025 Base = MakeAddrLValue(VecMem, E->getBase()->getType(),
4026 AlignmentSource::Decl);
4030 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers());
4032 // Encode the element access list into a vector of unsigned indices.
4033 SmallVector<uint32_t, 4> Indices;
4034 E->getEncodedElementAccess(Indices);
4036 if (Base.isSimple()) {
4037 llvm::Constant *CV =
4038 llvm::ConstantDataVector::get(getLLVMContext(), Indices);
4039 return LValue::MakeExtVectorElt(Base.getAddress(*this), CV, type,
4040 Base.getBaseInfo(), TBAAAccessInfo());
4042 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
4044 llvm::Constant *BaseElts = Base.getExtVectorElts();
4045 SmallVector<llvm::Constant *, 4> CElts;
4047 for (unsigned i = 0, e = Indices.size(); i != e; ++i)
4048 CElts.push_back(BaseElts->getAggregateElement(Indices[i]));
4049 llvm::Constant *CV = llvm::ConstantVector::get(CElts);
4050 return LValue::MakeExtVectorElt(Base.getExtVectorAddress(), CV, type,
4051 Base.getBaseInfo(), TBAAAccessInfo());
4054 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
4055 if (DeclRefExpr *DRE = tryToConvertMemberExprToDeclRefExpr(*this, E)) {
4056 EmitIgnoredExpr(E->getBase());
4057 return EmitDeclRefLValue(DRE);
4060 Expr *BaseExpr = E->getBase();
4061 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
4064 LValueBaseInfo BaseInfo;
4065 TBAAAccessInfo TBAAInfo;
4066 Address Addr = EmitPointerWithAlignment(BaseExpr, &BaseInfo, &TBAAInfo);
4067 QualType PtrTy = BaseExpr->getType()->getPointeeType();
4068 SanitizerSet SkippedChecks;
4069 bool IsBaseCXXThis = IsWrappedCXXThis(BaseExpr);
4071 SkippedChecks.set(SanitizerKind::Alignment, true);
4072 if (IsBaseCXXThis || isa<DeclRefExpr>(BaseExpr))
4073 SkippedChecks.set(SanitizerKind::Null, true);
4074 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr.getPointer(), PtrTy,
4075 /*Alignment=*/CharUnits::Zero(), SkippedChecks);
4076 BaseLV = MakeAddrLValue(Addr, PtrTy, BaseInfo, TBAAInfo);
4078 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess);
4080 NamedDecl *ND = E->getMemberDecl();
4081 if (auto *Field = dyn_cast<FieldDecl>(ND)) {
4082 LValue LV = EmitLValueForField(BaseLV, Field);
4083 setObjCGCLValueClass(getContext(), E, LV);
4084 if (getLangOpts().OpenMP) {
4085 // If the member was explicitly marked as nontemporal, mark it as
4086 // nontemporal. If the base lvalue is marked as nontemporal, mark access
4087 // to children as nontemporal too.
4088 if ((IsWrappedCXXThis(BaseExpr) &&
4089 CGM.getOpenMPRuntime().isNontemporalDecl(Field)) ||
4090 BaseLV.isNontemporal())
4091 LV.setNontemporal(/*Value=*/true);
4096 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
4097 return EmitFunctionDeclLValue(*this, E, FD);
4099 llvm_unreachable("Unhandled member declaration!");
4102 /// Given that we are currently emitting a lambda, emit an l-value for
4103 /// one of its members.
4104 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) {
4105 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent()->isLambda());
4106 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent() == Field->getParent());
4107 QualType LambdaTagType =
4108 getContext().getTagDeclType(Field->getParent());
4109 LValue LambdaLV = MakeNaturalAlignAddrLValue(CXXABIThisValue, LambdaTagType);
4110 return EmitLValueForField(LambdaLV, Field);
4113 /// Get the field index in the debug info. The debug info structure/union
4114 /// will ignore the unnamed bitfields.
4115 unsigned CodeGenFunction::getDebugInfoFIndex(const RecordDecl *Rec,
4116 unsigned FieldIndex) {
4117 unsigned I = 0, Skipped = 0;
4119 for (auto F : Rec->getDefinition()->fields()) {
4120 if (I == FieldIndex)
4122 if (F->isUnnamedBitfield())
4127 return FieldIndex - Skipped;
4130 /// Get the address of a zero-sized field within a record. The resulting
4131 /// address doesn't necessarily have the right type.
4132 static Address emitAddrOfZeroSizeField(CodeGenFunction &CGF, Address Base,
4133 const FieldDecl *Field) {
4134 CharUnits Offset = CGF.getContext().toCharUnitsFromBits(
4135 CGF.getContext().getFieldOffset(Field));
4136 if (Offset.isZero())
4138 Base = CGF.Builder.CreateElementBitCast(Base, CGF.Int8Ty);
4139 return CGF.Builder.CreateConstInBoundsByteGEP(Base, Offset);
4142 /// Drill down to the storage of a field without walking into
4143 /// reference types.
4145 /// The resulting address doesn't necessarily have the right type.
4146 static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base,
4147 const FieldDecl *field) {
4148 if (field->isZeroSize(CGF.getContext()))
4149 return emitAddrOfZeroSizeField(CGF, base, field);
4151 const RecordDecl *rec = field->getParent();
4154 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
4156 return CGF.Builder.CreateStructGEP(base, idx, field->getName());
4159 static Address emitPreserveStructAccess(CodeGenFunction &CGF, LValue base,
4160 Address addr, const FieldDecl *field) {
4161 const RecordDecl *rec = field->getParent();
4162 llvm::DIType *DbgInfo = CGF.getDebugInfo()->getOrCreateStandaloneType(
4163 base.getType(), rec->getLocation());
4166 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
4168 return CGF.Builder.CreatePreserveStructAccessIndex(
4169 addr, idx, CGF.getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo);
4172 static bool hasAnyVptr(const QualType Type, const ASTContext &Context) {
4173 const auto *RD = Type.getTypePtr()->getAsCXXRecordDecl();
4177 if (RD->isDynamicClass())
4180 for (const auto &Base : RD->bases())
4181 if (hasAnyVptr(Base.getType(), Context))
4184 for (const FieldDecl *Field : RD->fields())
4185 if (hasAnyVptr(Field->getType(), Context))
4191 LValue CodeGenFunction::EmitLValueForField(LValue base,
4192 const FieldDecl *field) {
4193 LValueBaseInfo BaseInfo = base.getBaseInfo();
4195 if (field->isBitField()) {
4196 const CGRecordLayout &RL =
4197 CGM.getTypes().getCGRecordLayout(field->getParent());
4198 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field);
4199 Address Addr = base.getAddress(*this);
4200 unsigned Idx = RL.getLLVMFieldNo(field);
4201 const RecordDecl *rec = field->getParent();
4202 if (!IsInPreservedAIRegion &&
4203 (!getDebugInfo() || !rec->hasAttr<BPFPreserveAccessIndexAttr>())) {
4205 // For structs, we GEP to the field that the record layout suggests.
4206 Addr = Builder.CreateStructGEP(Addr, Idx, field->getName());
4208 llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateRecordType(
4209 getContext().getRecordType(rec), rec->getLocation());
4210 Addr = Builder.CreatePreserveStructAccessIndex(Addr, Idx,
4211 getDebugInfoFIndex(rec, field->getFieldIndex()),
4215 // Get the access type.
4216 llvm::Type *FieldIntTy =
4217 llvm::Type::getIntNTy(getLLVMContext(), Info.StorageSize);
4218 if (Addr.getElementType() != FieldIntTy)
4219 Addr = Builder.CreateElementBitCast(Addr, FieldIntTy);
4221 QualType fieldType =
4222 field->getType().withCVRQualifiers(base.getVRQualifiers());
4223 // TODO: Support TBAA for bit fields.
4224 LValueBaseInfo FieldBaseInfo(BaseInfo.getAlignmentSource());
4225 return LValue::MakeBitfield(Addr, Info, fieldType, FieldBaseInfo,
4229 // Fields of may-alias structures are may-alias themselves.
4230 // FIXME: this should get propagated down through anonymous structs
4232 QualType FieldType = field->getType();
4233 const RecordDecl *rec = field->getParent();
4234 AlignmentSource BaseAlignSource = BaseInfo.getAlignmentSource();
4235 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(BaseAlignSource));
4236 TBAAAccessInfo FieldTBAAInfo;
4237 if (base.getTBAAInfo().isMayAlias() ||
4238 rec->hasAttr<MayAliasAttr>() || FieldType->isVectorType()) {
4239 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo();
4240 } else if (rec->isUnion()) {
4241 // TODO: Support TBAA for unions.
4242 FieldTBAAInfo = TBAAAccessInfo::getMayAliasInfo();
4244 // If no base type been assigned for the base access, then try to generate
4245 // one for this base lvalue.
4246 FieldTBAAInfo = base.getTBAAInfo();
4247 if (!FieldTBAAInfo.BaseType) {
4248 FieldTBAAInfo.BaseType = CGM.getTBAABaseTypeInfo(base.getType());
4249 assert(!FieldTBAAInfo.Offset &&
4250 "Nonzero offset for an access with no base type!");
4253 // Adjust offset to be relative to the base type.
4254 const ASTRecordLayout &Layout =
4255 getContext().getASTRecordLayout(field->getParent());
4256 unsigned CharWidth = getContext().getCharWidth();
4257 if (FieldTBAAInfo.BaseType)
4258 FieldTBAAInfo.Offset +=
4259 Layout.getFieldOffset(field->getFieldIndex()) / CharWidth;
4261 // Update the final access type and size.
4262 FieldTBAAInfo.AccessType = CGM.getTBAATypeInfo(FieldType);
4263 FieldTBAAInfo.Size =
4264 getContext().getTypeSizeInChars(FieldType).getQuantity();
4267 Address addr = base.getAddress(*this);
4268 if (auto *ClassDef = dyn_cast<CXXRecordDecl>(rec)) {
4269 if (CGM.getCodeGenOpts().StrictVTablePointers &&
4270 ClassDef->isDynamicClass()) {
4271 // Getting to any field of dynamic object requires stripping dynamic
4272 // information provided by invariant.group. This is because accessing
4273 // fields may leak the real address of dynamic object, which could result
4274 // in miscompilation when leaked pointer would be compared.
4275 auto *stripped = Builder.CreateStripInvariantGroup(addr.getPointer());
4276 addr = Address(stripped, addr.getAlignment());
4280 unsigned RecordCVR = base.getVRQualifiers();
4281 if (rec->isUnion()) {
4282 // For unions, there is no pointer adjustment.
4283 if (CGM.getCodeGenOpts().StrictVTablePointers &&
4284 hasAnyVptr(FieldType, getContext()))
4285 // Because unions can easily skip invariant.barriers, we need to add
4286 // a barrier every time CXXRecord field with vptr is referenced.
4287 addr = Address(Builder.CreateLaunderInvariantGroup(addr.getPointer()),
4288 addr.getAlignment());
4290 if (IsInPreservedAIRegion ||
4291 (getDebugInfo() && rec->hasAttr<BPFPreserveAccessIndexAttr>())) {
4292 // Remember the original union field index
4293 llvm::DIType *DbgInfo = getDebugInfo()->getOrCreateStandaloneType(base.getType(),
4294 rec->getLocation());
4296 Builder.CreatePreserveUnionAccessIndex(
4297 addr.getPointer(), getDebugInfoFIndex(rec, field->getFieldIndex()), DbgInfo),
4298 addr.getAlignment());
4301 if (FieldType->isReferenceType())
4302 addr = Builder.CreateElementBitCast(
4303 addr, CGM.getTypes().ConvertTypeForMem(FieldType), field->getName());
4305 if (!IsInPreservedAIRegion &&
4306 (!getDebugInfo() || !rec->hasAttr<BPFPreserveAccessIndexAttr>()))
4307 // For structs, we GEP to the field that the record layout suggests.
4308 addr = emitAddrOfFieldStorage(*this, addr, field);
4310 // Remember the original struct field index
4311 addr = emitPreserveStructAccess(*this, base, addr, field);
4314 // If this is a reference field, load the reference right now.
4315 if (FieldType->isReferenceType()) {
4317 MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo);
4318 if (RecordCVR & Qualifiers::Volatile)
4319 RefLVal.getQuals().addVolatile();
4320 addr = EmitLoadOfReference(RefLVal, &FieldBaseInfo, &FieldTBAAInfo);
4322 // Qualifiers on the struct don't apply to the referencee.
4324 FieldType = FieldType->getPointeeType();
4327 // Make sure that the address is pointing to the right type. This is critical
4328 // for both unions and structs. A union needs a bitcast, a struct element
4329 // will need a bitcast if the LLVM type laid out doesn't match the desired
4331 addr = Builder.CreateElementBitCast(
4332 addr, CGM.getTypes().ConvertTypeForMem(FieldType), field->getName());
4334 if (field->hasAttr<AnnotateAttr>())
4335 addr = EmitFieldAnnotations(field, addr);
4337 LValue LV = MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo);
4338 LV.getQuals().addCVRQualifiers(RecordCVR);
4340 // __weak attribute on a field is ignored.
4341 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
4342 LV.getQuals().removeObjCGCAttr();
4348 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base,
4349 const FieldDecl *Field) {
4350 QualType FieldType = Field->getType();
4352 if (!FieldType->isReferenceType())
4353 return EmitLValueForField(Base, Field);
4355 Address V = emitAddrOfFieldStorage(*this, Base.getAddress(*this), Field);
4357 // Make sure that the address is pointing to the right type.
4358 llvm::Type *llvmType = ConvertTypeForMem(FieldType);
4359 V = Builder.CreateElementBitCast(V, llvmType, Field->getName());
4361 // TODO: Generate TBAA information that describes this access as a structure
4362 // member access and not just an access to an object of the field's type. This
4363 // should be similar to what we do in EmitLValueForField().
4364 LValueBaseInfo BaseInfo = Base.getBaseInfo();
4365 AlignmentSource FieldAlignSource = BaseInfo.getAlignmentSource();
4366 LValueBaseInfo FieldBaseInfo(getFieldAlignmentSource(FieldAlignSource));
4367 return MakeAddrLValue(V, FieldType, FieldBaseInfo,
4368 CGM.getTBAAInfoForSubobject(Base, FieldType));
4371 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
4372 if (E->isFileScope()) {
4373 ConstantAddress GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E);
4374 return MakeAddrLValue(GlobalPtr, E->getType(), AlignmentSource::Decl);
4376 if (E->getType()->isVariablyModifiedType())
4377 // make sure to emit the VLA size.
4378 EmitVariablyModifiedType(E->getType());
4380 Address DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
4381 const Expr *InitExpr = E->getInitializer();
4382 LValue Result = MakeAddrLValue(DeclPtr, E->getType(), AlignmentSource::Decl);
4384 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(),
4387 // Block-scope compound literals are destroyed at the end of the enclosing
4389 if (!getLangOpts().CPlusPlus)
4390 if (QualType::DestructionKind DtorKind = E->getType().isDestructedType())
4391 pushLifetimeExtendedDestroy(getCleanupKind(DtorKind), DeclPtr,
4392 E->getType(), getDestroyer(DtorKind),
4393 DtorKind & EHCleanup);
4398 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) {
4399 if (!E->isGLValue())
4400 // Initializing an aggregate temporary in C++11: T{...}.
4401 return EmitAggExprToLValue(E);
4403 // An lvalue initializer list must be initializing a reference.
4404 assert(E->isTransparent() && "non-transparent glvalue init list");
4405 return EmitLValue(E->getInit(0));
4408 /// Emit the operand of a glvalue conditional operator. This is either a glvalue
4409 /// or a (possibly-parenthesized) throw-expression. If this is a throw, no
4410 /// LValue is returned and the current block has been terminated.
4411 static Optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF,
4412 const Expr *Operand) {
4413 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) {
4414 CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false);
4418 return CGF.EmitLValue(Operand);
4421 LValue CodeGenFunction::
4422 EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) {
4423 if (!expr->isGLValue()) {
4424 // ?: here should be an aggregate.
4425 assert(hasAggregateEvaluationKind(expr->getType()) &&
4426 "Unexpected conditional operator!");
4427 return EmitAggExprToLValue(expr);
4430 OpaqueValueMapping binding(*this, expr);
4432 const Expr *condExpr = expr->getCond();
4434 if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
4435 const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr();
4436 if (!CondExprBool) std::swap(live, dead);
4438 if (!ContainsLabel(dead)) {
4439 // If the true case is live, we need to track its region.
4441 incrementProfileCounter(expr);
4442 // If a throw expression we emit it and return an undefined lvalue
4443 // because it can't be used.
4444 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(live->IgnoreParens())) {
4445 EmitCXXThrowExpr(ThrowExpr);
4447 llvm::PointerType::getUnqual(ConvertType(dead->getType()));
4448 return MakeAddrLValue(
4449 Address(llvm::UndefValue::get(Ty), CharUnits::One()),
4452 return EmitLValue(live);
4456 llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true");
4457 llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false");
4458 llvm::BasicBlock *contBlock = createBasicBlock("cond.end");
4460 ConditionalEvaluation eval(*this);
4461 EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock, getProfileCount(expr));
4463 // Any temporaries created here are conditional.
4464 EmitBlock(lhsBlock);
4465 incrementProfileCounter(expr);
4467 Optional<LValue> lhs =
4468 EmitLValueOrThrowExpression(*this, expr->getTrueExpr());
4471 if (lhs && !lhs->isSimple())
4472 return EmitUnsupportedLValue(expr, "conditional operator");
4474 lhsBlock = Builder.GetInsertBlock();
4476 Builder.CreateBr(contBlock);
4478 // Any temporaries created here are conditional.
4479 EmitBlock(rhsBlock);
4481 Optional<LValue> rhs =
4482 EmitLValueOrThrowExpression(*this, expr->getFalseExpr());
4484 if (rhs && !rhs->isSimple())
4485 return EmitUnsupportedLValue(expr, "conditional operator");
4486 rhsBlock = Builder.GetInsertBlock();
4488 EmitBlock(contBlock);
4491 llvm::PHINode *phi =
4492 Builder.CreatePHI(lhs->getPointer(*this)->getType(), 2, "cond-lvalue");
4493 phi->addIncoming(lhs->getPointer(*this), lhsBlock);
4494 phi->addIncoming(rhs->getPointer(*this), rhsBlock);
4495 Address result(phi, std::min(lhs->getAlignment(), rhs->getAlignment()));
4496 AlignmentSource alignSource =
4497 std::max(lhs->getBaseInfo().getAlignmentSource(),
4498 rhs->getBaseInfo().getAlignmentSource());
4499 TBAAAccessInfo TBAAInfo = CGM.mergeTBAAInfoForConditionalOperator(
4500 lhs->getTBAAInfo(), rhs->getTBAAInfo());
4501 return MakeAddrLValue(result, expr->getType(), LValueBaseInfo(alignSource),
4504 assert((lhs || rhs) &&
4505 "both operands of glvalue conditional are throw-expressions?");
4506 return lhs ? *lhs : *rhs;
4510 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference
4511 /// type. If the cast is to a reference, we can have the usual lvalue result,
4512 /// otherwise if a cast is needed by the code generator in an lvalue context,
4513 /// then it must mean that we need the address of an aggregate in order to
4514 /// access one of its members. This can happen for all the reasons that casts
4515 /// are permitted with aggregate result, including noop aggregate casts, and
4516 /// cast from scalar to union.
4517 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
4518 switch (E->getCastKind()) {
4521 case CK_LValueToRValueBitCast:
4522 case CK_ArrayToPointerDecay:
4523 case CK_FunctionToPointerDecay:
4524 case CK_NullToMemberPointer:
4525 case CK_NullToPointer:
4526 case CK_IntegralToPointer:
4527 case CK_PointerToIntegral:
4528 case CK_PointerToBoolean:
4529 case CK_VectorSplat:
4530 case CK_IntegralCast:
4531 case CK_BooleanToSignedIntegral:
4532 case CK_IntegralToBoolean:
4533 case CK_IntegralToFloating:
4534 case CK_FloatingToIntegral:
4535 case CK_FloatingToBoolean:
4536 case CK_FloatingCast:
4537 case CK_FloatingRealToComplex:
4538 case CK_FloatingComplexToReal:
4539 case CK_FloatingComplexToBoolean:
4540 case CK_FloatingComplexCast:
4541 case CK_FloatingComplexToIntegralComplex:
4542 case CK_IntegralRealToComplex:
4543 case CK_IntegralComplexToReal:
4544 case CK_IntegralComplexToBoolean:
4545 case CK_IntegralComplexCast:
4546 case CK_IntegralComplexToFloatingComplex:
4547 case CK_DerivedToBaseMemberPointer:
4548 case CK_BaseToDerivedMemberPointer:
4549 case CK_MemberPointerToBoolean:
4550 case CK_ReinterpretMemberPointer:
4551 case CK_AnyPointerToBlockPointerCast:
4552 case CK_ARCProduceObject:
4553 case CK_ARCConsumeObject:
4554 case CK_ARCReclaimReturnedObject:
4555 case CK_ARCExtendBlockObject:
4556 case CK_CopyAndAutoreleaseBlockObject:
4557 case CK_IntToOCLSampler:
4558 case CK_FixedPointCast:
4559 case CK_FixedPointToBoolean:
4560 case CK_FixedPointToIntegral:
4561 case CK_IntegralToFixedPoint:
4562 return EmitUnsupportedLValue(E, "unexpected cast lvalue");
4565 llvm_unreachable("dependent cast kind in IR gen!");
4567 case CK_BuiltinFnToFnPtr:
4568 llvm_unreachable("builtin functions are handled elsewhere");
4570 // These are never l-values; just use the aggregate emission code.
4571 case CK_NonAtomicToAtomic:
4572 case CK_AtomicToNonAtomic:
4573 return EmitAggExprToLValue(E);
4576 LValue LV = EmitLValue(E->getSubExpr());
4577 Address V = LV.getAddress(*this);
4578 const auto *DCE = cast<CXXDynamicCastExpr>(E);
4579 return MakeNaturalAlignAddrLValue(EmitDynamicCast(V, DCE), E->getType());
4582 case CK_ConstructorConversion:
4583 case CK_UserDefinedConversion:
4584 case CK_CPointerToObjCPointerCast:
4585 case CK_BlockPointerToObjCPointerCast:
4587 case CK_LValueToRValue:
4588 return EmitLValue(E->getSubExpr());
4590 case CK_UncheckedDerivedToBase:
4591 case CK_DerivedToBase: {
4592 const auto *DerivedClassTy =
4593 E->getSubExpr()->getType()->castAs<RecordType>();
4594 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
4596 LValue LV = EmitLValue(E->getSubExpr());
4597 Address This = LV.getAddress(*this);
4599 // Perform the derived-to-base conversion
4600 Address Base = GetAddressOfBaseClass(
4601 This, DerivedClassDecl, E->path_begin(), E->path_end(),
4602 /*NullCheckValue=*/false, E->getExprLoc());
4604 // TODO: Support accesses to members of base classes in TBAA. For now, we
4605 // conservatively pretend that the complete object is of the base class
4607 return MakeAddrLValue(Base, E->getType(), LV.getBaseInfo(),
4608 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4611 return EmitAggExprToLValue(E);
4612 case CK_BaseToDerived: {
4613 const auto *DerivedClassTy = E->getType()->castAs<RecordType>();
4614 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
4616 LValue LV = EmitLValue(E->getSubExpr());
4618 // Perform the base-to-derived conversion
4619 Address Derived = GetAddressOfDerivedClass(
4620 LV.getAddress(*this), DerivedClassDecl, E->path_begin(), E->path_end(),
4621 /*NullCheckValue=*/false);
4623 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is
4624 // performed and the object is not of the derived type.
4625 if (sanitizePerformTypeCheck())
4626 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(),
4627 Derived.getPointer(), E->getType());
4629 if (SanOpts.has(SanitizerKind::CFIDerivedCast))
4630 EmitVTablePtrCheckForCast(E->getType(), Derived.getPointer(),
4631 /*MayBeNull=*/false, CFITCK_DerivedCast,
4634 return MakeAddrLValue(Derived, E->getType(), LV.getBaseInfo(),
4635 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4637 case CK_LValueBitCast: {
4638 // This must be a reinterpret_cast (or c-style equivalent).
4639 const auto *CE = cast<ExplicitCastExpr>(E);
4641 CGM.EmitExplicitCastExprType(CE, this);
4642 LValue LV = EmitLValue(E->getSubExpr());
4643 Address V = Builder.CreateBitCast(LV.getAddress(*this),
4644 ConvertType(CE->getTypeAsWritten()));
4646 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast))
4647 EmitVTablePtrCheckForCast(E->getType(), V.getPointer(),
4648 /*MayBeNull=*/false, CFITCK_UnrelatedCast,
4651 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(),
4652 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4654 case CK_AddressSpaceConversion: {
4655 LValue LV = EmitLValue(E->getSubExpr());
4656 QualType DestTy = getContext().getPointerType(E->getType());
4657 llvm::Value *V = getTargetHooks().performAddrSpaceCast(
4658 *this, LV.getPointer(*this),
4659 E->getSubExpr()->getType().getAddressSpace(),
4660 E->getType().getAddressSpace(), ConvertType(DestTy));
4661 return MakeAddrLValue(Address(V, LV.getAddress(*this).getAlignment()),
4662 E->getType(), LV.getBaseInfo(), LV.getTBAAInfo());
4664 case CK_ObjCObjectLValueCast: {
4665 LValue LV = EmitLValue(E->getSubExpr());
4666 Address V = Builder.CreateElementBitCast(LV.getAddress(*this),
4667 ConvertType(E->getType()));
4668 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo(),
4669 CGM.getTBAAInfoForSubobject(LV, E->getType()));
4671 case CK_ZeroToOCLOpaqueType:
4672 llvm_unreachable("NULL to OpenCL opaque type lvalue cast is not valid");
4675 llvm_unreachable("Unhandled lvalue cast kind?");
4678 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
4679 assert(OpaqueValueMappingData::shouldBindAsLValue(e));
4680 return getOrCreateOpaqueLValueMapping(e);
4684 CodeGenFunction::getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e) {
4685 assert(OpaqueValueMapping::shouldBindAsLValue(e));
4687 llvm::DenseMap<const OpaqueValueExpr*,LValue>::iterator
4688 it = OpaqueLValues.find(e);
4690 if (it != OpaqueLValues.end())
4693 assert(e->isUnique() && "LValue for a nonunique OVE hasn't been emitted");
4694 return EmitLValue(e->getSourceExpr());
4698 CodeGenFunction::getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e) {
4699 assert(!OpaqueValueMapping::shouldBindAsLValue(e));
4701 llvm::DenseMap<const OpaqueValueExpr*,RValue>::iterator
4702 it = OpaqueRValues.find(e);
4704 if (it != OpaqueRValues.end())
4707 assert(e->isUnique() && "RValue for a nonunique OVE hasn't been emitted");
4708 return EmitAnyExpr(e->getSourceExpr());
4711 RValue CodeGenFunction::EmitRValueForField(LValue LV,
4712 const FieldDecl *FD,
4713 SourceLocation Loc) {
4714 QualType FT = FD->getType();
4715 LValue FieldLV = EmitLValueForField(LV, FD);
4716 switch (getEvaluationKind(FT)) {
4718 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc));
4720 return FieldLV.asAggregateRValue(*this);
4722 // This routine is used to load fields one-by-one to perform a copy, so
4723 // don't load reference fields.
4724 if (FD->getType()->isReferenceType())
4725 return RValue::get(FieldLV.getPointer(*this));
4726 // Call EmitLoadOfScalar except when the lvalue is a bitfield to emit a
4728 if (FieldLV.isBitField())
4729 return EmitLoadOfLValue(FieldLV, Loc);
4730 return RValue::get(EmitLoadOfScalar(FieldLV, Loc));
4732 llvm_unreachable("bad evaluation kind");
4735 //===--------------------------------------------------------------------===//
4736 // Expression Emission
4737 //===--------------------------------------------------------------------===//
4739 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
4740 ReturnValueSlot ReturnValue) {
4741 // Builtins never have block type.
4742 if (E->getCallee()->getType()->isBlockPointerType())
4743 return EmitBlockCallExpr(E, ReturnValue);
4745 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E))
4746 return EmitCXXMemberCallExpr(CE, ReturnValue);
4748 if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E))
4749 return EmitCUDAKernelCallExpr(CE, ReturnValue);
4751 if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E))
4752 if (const CXXMethodDecl *MD =
4753 dyn_cast_or_null<CXXMethodDecl>(CE->getCalleeDecl()))
4754 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
4756 CGCallee callee = EmitCallee(E->getCallee());
4758 if (callee.isBuiltin()) {
4759 return EmitBuiltinExpr(callee.getBuiltinDecl(), callee.getBuiltinID(),
4763 if (callee.isPseudoDestructor()) {
4764 return EmitCXXPseudoDestructorExpr(callee.getPseudoDestructorExpr());
4767 return EmitCall(E->getCallee()->getType(), callee, E, ReturnValue);
4770 /// Emit a CallExpr without considering whether it might be a subclass.
4771 RValue CodeGenFunction::EmitSimpleCallExpr(const CallExpr *E,
4772 ReturnValueSlot ReturnValue) {
4773 CGCallee Callee = EmitCallee(E->getCallee());
4774 return EmitCall(E->getCallee()->getType(), Callee, E, ReturnValue);
4777 static CGCallee EmitDirectCallee(CodeGenFunction &CGF, GlobalDecl GD) {
4778 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
4780 if (auto builtinID = FD->getBuiltinID()) {
4781 // Replaceable builtin provide their own implementation of a builtin. Unless
4782 // we are in the builtin implementation itself, don't call the actual
4783 // builtin. If we are in the builtin implementation, avoid trivial infinite
4785 if (!FD->isInlineBuiltinDeclaration() ||
4786 CGF.CurFn->getName() == FD->getName())
4787 return CGCallee::forBuiltin(builtinID, FD);
4790 llvm::Constant *calleePtr = EmitFunctionDeclPointer(CGF.CGM, GD);
4791 return CGCallee::forDirect(calleePtr, GD);
4794 CGCallee CodeGenFunction::EmitCallee(const Expr *E) {
4795 E = E->IgnoreParens();
4797 // Look through function-to-pointer decay.
4798 if (auto ICE = dyn_cast<ImplicitCastExpr>(E)) {
4799 if (ICE->getCastKind() == CK_FunctionToPointerDecay ||
4800 ICE->getCastKind() == CK_BuiltinFnToFnPtr) {
4801 return EmitCallee(ICE->getSubExpr());
4804 // Resolve direct calls.
4805 } else if (auto DRE = dyn_cast<DeclRefExpr>(E)) {
4806 if (auto FD = dyn_cast<FunctionDecl>(DRE->getDecl())) {
4807 return EmitDirectCallee(*this, FD);
4809 } else if (auto ME = dyn_cast<MemberExpr>(E)) {
4810 if (auto FD = dyn_cast<FunctionDecl>(ME->getMemberDecl())) {
4811 EmitIgnoredExpr(ME->getBase());
4812 return EmitDirectCallee(*this, FD);
4815 // Look through template substitutions.
4816 } else if (auto NTTP = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
4817 return EmitCallee(NTTP->getReplacement());
4819 // Treat pseudo-destructor calls differently.
4820 } else if (auto PDE = dyn_cast<CXXPseudoDestructorExpr>(E)) {
4821 return CGCallee::forPseudoDestructor(PDE);
4824 // Otherwise, we have an indirect reference.
4825 llvm::Value *calleePtr;
4826 QualType functionType;
4827 if (auto ptrType = E->getType()->getAs<PointerType>()) {
4828 calleePtr = EmitScalarExpr(E);
4829 functionType = ptrType->getPointeeType();
4831 functionType = E->getType();
4832 calleePtr = EmitLValue(E).getPointer(*this);
4834 assert(functionType->isFunctionType());
4837 if (const auto *VD =
4838 dyn_cast_or_null<VarDecl>(E->getReferencedDeclOfCallee()))
4839 GD = GlobalDecl(VD);
4841 CGCalleeInfo calleeInfo(functionType->getAs<FunctionProtoType>(), GD);
4842 CGCallee callee(calleeInfo, calleePtr);
4846 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
4847 // Comma expressions just emit their LHS then their RHS as an l-value.
4848 if (E->getOpcode() == BO_Comma) {
4849 EmitIgnoredExpr(E->getLHS());
4850 EnsureInsertPoint();
4851 return EmitLValue(E->getRHS());
4854 if (E->getOpcode() == BO_PtrMemD ||
4855 E->getOpcode() == BO_PtrMemI)
4856 return EmitPointerToDataMemberBinaryExpr(E);
4858 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
4860 // Note that in all of these cases, __block variables need the RHS
4861 // evaluated first just in case the variable gets moved by the RHS.
4863 switch (getEvaluationKind(E->getType())) {
4865 switch (E->getLHS()->getType().getObjCLifetime()) {
4866 case Qualifiers::OCL_Strong:
4867 return EmitARCStoreStrong(E, /*ignored*/ false).first;
4869 case Qualifiers::OCL_Autoreleasing:
4870 return EmitARCStoreAutoreleasing(E).first;
4872 // No reason to do any of these differently.
4873 case Qualifiers::OCL_None:
4874 case Qualifiers::OCL_ExplicitNone:
4875 case Qualifiers::OCL_Weak:
4879 RValue RV = EmitAnyExpr(E->getRHS());
4880 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store);
4882 EmitNullabilityCheck(LV, RV.getScalarVal(), E->getExprLoc());
4883 EmitStoreThroughLValue(RV, LV);
4884 if (getLangOpts().OpenMP)
4885 CGM.getOpenMPRuntime().checkAndEmitLastprivateConditional(*this,
4891 return EmitComplexAssignmentLValue(E);
4894 return EmitAggExprToLValue(E);
4896 llvm_unreachable("bad evaluation kind");
4899 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
4900 RValue RV = EmitCallExpr(E);
4903 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4904 AlignmentSource::Decl);
4906 assert(E->getCallReturnType(getContext())->isReferenceType() &&
4907 "Can't have a scalar return unless the return type is a "
4910 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4913 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
4914 // FIXME: This shouldn't require another copy.
4915 return EmitAggExprToLValue(E);
4918 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
4919 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
4920 && "binding l-value to type which needs a temporary");
4921 AggValueSlot Slot = CreateAggTemp(E->getType());
4922 EmitCXXConstructExpr(E, Slot);
4923 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl);
4927 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
4928 return MakeNaturalAlignAddrLValue(EmitCXXTypeidExpr(E), E->getType());
4931 Address CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) {
4932 return Builder.CreateElementBitCast(CGM.GetAddrOfMSGuidDecl(E->getGuidDecl()),
4933 ConvertType(E->getType()));
4936 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) {
4937 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType(),
4938 AlignmentSource::Decl);
4942 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
4943 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
4944 Slot.setExternallyDestructed();
4945 EmitAggExpr(E->getSubExpr(), Slot);
4946 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddress());
4947 return MakeAddrLValue(Slot.getAddress(), E->getType(), AlignmentSource::Decl);
4950 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
4951 RValue RV = EmitObjCMessageExpr(E);
4954 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4955 AlignmentSource::Decl);
4957 assert(E->getMethodDecl()->getReturnType()->isReferenceType() &&
4958 "Can't have a scalar return unless the return type is a "
4961 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4964 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
4966 CGM.getObjCRuntime().GetAddrOfSelector(*this, E->getSelector());
4967 return MakeAddrLValue(V, E->getType(), AlignmentSource::Decl);
4970 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
4971 const ObjCIvarDecl *Ivar) {
4972 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
4975 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
4976 llvm::Value *BaseValue,
4977 const ObjCIvarDecl *Ivar,
4978 unsigned CVRQualifiers) {
4979 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
4980 Ivar, CVRQualifiers);
4983 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
4984 // FIXME: A lot of the code below could be shared with EmitMemberExpr.
4985 llvm::Value *BaseValue = nullptr;
4986 const Expr *BaseExpr = E->getBase();
4987 Qualifiers BaseQuals;
4990 BaseValue = EmitScalarExpr(BaseExpr);
4991 ObjectTy = BaseExpr->getType()->getPointeeType();
4992 BaseQuals = ObjectTy.getQualifiers();
4994 LValue BaseLV = EmitLValue(BaseExpr);
4995 BaseValue = BaseLV.getPointer(*this);
4996 ObjectTy = BaseExpr->getType();
4997 BaseQuals = ObjectTy.getQualifiers();
5001 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
5002 BaseQuals.getCVRQualifiers());
5003 setObjCGCLValueClass(getContext(), E, LV);
5007 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
5008 // Can only get l-value for message expression returning aggregate type
5009 RValue RV = EmitAnyExprToTemp(E);
5010 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
5011 AlignmentSource::Decl);
5014 RValue CodeGenFunction::EmitCall(QualType CalleeType, const CGCallee &OrigCallee,
5015 const CallExpr *E, ReturnValueSlot ReturnValue,
5016 llvm::Value *Chain) {
5017 // Get the actual function type. The callee type will always be a pointer to
5018 // function type or a block pointer type.
5019 assert(CalleeType->isFunctionPointerType() &&
5020 "Call must have function pointer type!");
5022 const Decl *TargetDecl =
5023 OrigCallee.getAbstractInfo().getCalleeDecl().getDecl();
5025 CalleeType = getContext().getCanonicalType(CalleeType);
5027 auto PointeeType = cast<PointerType>(CalleeType)->getPointeeType();
5029 CGCallee Callee = OrigCallee;
5031 if (getLangOpts().CPlusPlus && SanOpts.has(SanitizerKind::Function) &&
5032 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
5033 if (llvm::Constant *PrefixSig =
5034 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) {
5035 SanitizerScope SanScope(this);
5036 // Remove any (C++17) exception specifications, to allow calling e.g. a
5037 // noexcept function through a non-noexcept pointer.
5039 getContext().getFunctionTypeWithExceptionSpec(PointeeType, EST_None);
5040 llvm::Constant *FTRTTIConst =
5041 CGM.GetAddrOfRTTIDescriptor(ProtoTy, /*ForEH=*/true);
5042 llvm::Type *PrefixStructTyElems[] = {PrefixSig->getType(), Int32Ty};
5043 llvm::StructType *PrefixStructTy = llvm::StructType::get(
5044 CGM.getLLVMContext(), PrefixStructTyElems, /*isPacked=*/true);
5046 llvm::Value *CalleePtr = Callee.getFunctionPointer();
5048 llvm::Value *CalleePrefixStruct = Builder.CreateBitCast(
5049 CalleePtr, llvm::PointerType::getUnqual(PrefixStructTy));
5050 llvm::Value *CalleeSigPtr =
5051 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 0);
5052 llvm::Value *CalleeSig =
5053 Builder.CreateAlignedLoad(CalleeSigPtr, getIntAlign());
5054 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig);
5056 llvm::BasicBlock *Cont = createBasicBlock("cont");
5057 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck");
5058 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont);
5060 EmitBlock(TypeCheck);
5061 llvm::Value *CalleeRTTIPtr =
5062 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 1);
5063 llvm::Value *CalleeRTTIEncoded =
5064 Builder.CreateAlignedLoad(CalleeRTTIPtr, getPointerAlign());
5065 llvm::Value *CalleeRTTI =
5066 DecodeAddrUsedInPrologue(CalleePtr, CalleeRTTIEncoded);
5067 llvm::Value *CalleeRTTIMatch =
5068 Builder.CreateICmpEQ(CalleeRTTI, FTRTTIConst);
5069 llvm::Constant *StaticData[] = {EmitCheckSourceLocation(E->getBeginLoc()),
5070 EmitCheckTypeDescriptor(CalleeType)};
5071 EmitCheck(std::make_pair(CalleeRTTIMatch, SanitizerKind::Function),
5072 SanitizerHandler::FunctionTypeMismatch, StaticData,
5073 {CalleePtr, CalleeRTTI, FTRTTIConst});
5075 Builder.CreateBr(Cont);
5080 const auto *FnType = cast<FunctionType>(PointeeType);
5082 // If we are checking indirect calls and this call is indirect, check that the
5083 // function pointer is a member of the bit set for the function type.
5084 if (SanOpts.has(SanitizerKind::CFIICall) &&
5085 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
5086 SanitizerScope SanScope(this);
5087 EmitSanitizerStatReport(llvm::SanStat_CFI_ICall);
5090 if (CGM.getCodeGenOpts().SanitizeCfiICallGeneralizePointers)
5091 MD = CGM.CreateMetadataIdentifierGeneralized(QualType(FnType, 0));
5093 MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0));
5095 llvm::Value *TypeId = llvm::MetadataAsValue::get(getLLVMContext(), MD);
5097 llvm::Value *CalleePtr = Callee.getFunctionPointer();
5098 llvm::Value *CastedCallee = Builder.CreateBitCast(CalleePtr, Int8PtrTy);
5099 llvm::Value *TypeTest = Builder.CreateCall(
5100 CGM.getIntrinsic(llvm::Intrinsic::type_test), {CastedCallee, TypeId});
5102 auto CrossDsoTypeId = CGM.CreateCrossDsoCfiTypeId(MD);
5103 llvm::Constant *StaticData[] = {
5104 llvm::ConstantInt::get(Int8Ty, CFITCK_ICall),
5105 EmitCheckSourceLocation(E->getBeginLoc()),
5106 EmitCheckTypeDescriptor(QualType(FnType, 0)),
5108 if (CGM.getCodeGenOpts().SanitizeCfiCrossDso && CrossDsoTypeId) {
5109 EmitCfiSlowPathCheck(SanitizerKind::CFIICall, TypeTest, CrossDsoTypeId,
5110 CastedCallee, StaticData);
5112 EmitCheck(std::make_pair(TypeTest, SanitizerKind::CFIICall),
5113 SanitizerHandler::CFICheckFail, StaticData,
5114 {CastedCallee, llvm::UndefValue::get(IntPtrTy)});
5120 Args.add(RValue::get(Builder.CreateBitCast(Chain, CGM.VoidPtrTy)),
5121 CGM.getContext().VoidPtrTy);
5123 // C++17 requires that we evaluate arguments to a call using assignment syntax
5124 // right-to-left, and that we evaluate arguments to certain other operators
5125 // left-to-right. Note that we allow this to override the order dictated by
5126 // the calling convention on the MS ABI, which means that parameter
5127 // destruction order is not necessarily reverse construction order.
5128 // FIXME: Revisit this based on C++ committee response to unimplementability.
5129 EvaluationOrder Order = EvaluationOrder::Default;
5130 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(E)) {
5131 if (OCE->isAssignmentOp())
5132 Order = EvaluationOrder::ForceRightToLeft;
5134 switch (OCE->getOperator()) {
5136 case OO_GreaterGreater:
5141 Order = EvaluationOrder::ForceLeftToRight;
5149 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), E->arguments(),
5150 E->getDirectCallee(), /*ParamsToSkip*/ 0, Order);
5152 const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeFreeFunctionCall(
5153 Args, FnType, /*ChainCall=*/Chain);
5156 // If the expression that denotes the called function has a type
5157 // that does not include a prototype, [the default argument
5158 // promotions are performed]. If the number of arguments does not
5159 // equal the number of parameters, the behavior is undefined. If
5160 // the function is defined with a type that includes a prototype,
5161 // and either the prototype ends with an ellipsis (, ...) or the
5162 // types of the arguments after promotion are not compatible with
5163 // the types of the parameters, the behavior is undefined. If the
5164 // function is defined with a type that does not include a
5165 // prototype, and the types of the arguments after promotion are
5166 // not compatible with those of the parameters after promotion,
5167 // the behavior is undefined [except in some trivial cases].
5168 // That is, in the general case, we should assume that a call
5169 // through an unprototyped function type works like a *non-variadic*
5170 // call. The way we make this work is to cast to the exact type
5171 // of the promoted arguments.
5173 // Chain calls use this same code path to add the invisible chain parameter
5174 // to the function type.
5175 if (isa<FunctionNoProtoType>(FnType) || Chain) {
5176 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo);
5177 int AS = Callee.getFunctionPointer()->getType()->getPointerAddressSpace();
5178 CalleeTy = CalleeTy->getPointerTo(AS);
5180 llvm::Value *CalleePtr = Callee.getFunctionPointer();
5181 CalleePtr = Builder.CreateBitCast(CalleePtr, CalleeTy, "callee.knr.cast");
5182 Callee.setFunctionPointer(CalleePtr);
5185 llvm::CallBase *CallOrInvoke = nullptr;
5186 RValue Call = EmitCall(FnInfo, Callee, ReturnValue, Args, &CallOrInvoke,
5189 // Generate function declaration DISuprogram in order to be used
5190 // in debug info about call sites.
5191 if (CGDebugInfo *DI = getDebugInfo()) {
5192 if (auto *CalleeDecl = dyn_cast_or_null<FunctionDecl>(TargetDecl))
5193 DI->EmitFuncDeclForCallSite(CallOrInvoke, QualType(FnType, 0),
5200 LValue CodeGenFunction::
5201 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
5202 Address BaseAddr = Address::invalid();
5203 if (E->getOpcode() == BO_PtrMemI) {
5204 BaseAddr = EmitPointerWithAlignment(E->getLHS());
5206 BaseAddr = EmitLValue(E->getLHS()).getAddress(*this);
5209 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
5210 const auto *MPT = E->getRHS()->getType()->castAs<MemberPointerType>();
5212 LValueBaseInfo BaseInfo;
5213 TBAAAccessInfo TBAAInfo;
5214 Address MemberAddr =
5215 EmitCXXMemberDataPointerAddress(E, BaseAddr, OffsetV, MPT, &BaseInfo,
5218 return MakeAddrLValue(MemberAddr, MPT->getPointeeType(), BaseInfo, TBAAInfo);
5221 /// Given the address of a temporary variable, produce an r-value of
5223 RValue CodeGenFunction::convertTempToRValue(Address addr,
5225 SourceLocation loc) {
5226 LValue lvalue = MakeAddrLValue(addr, type, AlignmentSource::Decl);
5227 switch (getEvaluationKind(type)) {
5229 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc));
5231 return lvalue.asAggregateRValue(*this);
5233 return RValue::get(EmitLoadOfScalar(lvalue, loc));
5235 llvm_unreachable("bad evaluation kind");
5238 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) {
5239 assert(Val->getType()->isFPOrFPVectorTy());
5240 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val))
5243 llvm::MDBuilder MDHelper(getLLVMContext());
5244 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy);
5246 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node);
5250 struct LValueOrRValue {
5256 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF,
5257 const PseudoObjectExpr *E,
5259 AggValueSlot slot) {
5260 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
5262 // Find the result expression, if any.
5263 const Expr *resultExpr = E->getResultExpr();
5264 LValueOrRValue result;
5266 for (PseudoObjectExpr::const_semantics_iterator
5267 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
5268 const Expr *semantic = *i;
5270 // If this semantic expression is an opaque value, bind it
5271 // to the result of its source expression.
5272 if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
5273 // Skip unique OVEs.
5274 if (ov->isUnique()) {
5275 assert(ov != resultExpr &&
5276 "A unique OVE cannot be used as the result expression");
5280 // If this is the result expression, we may need to evaluate
5281 // directly into the slot.
5282 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
5284 if (ov == resultExpr && ov->isRValue() && !forLValue &&
5285 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) {
5286 CGF.EmitAggExpr(ov->getSourceExpr(), slot);
5287 LValue LV = CGF.MakeAddrLValue(slot.getAddress(), ov->getType(),
5288 AlignmentSource::Decl);
5289 opaqueData = OVMA::bind(CGF, ov, LV);
5290 result.RV = slot.asRValue();
5292 // Otherwise, emit as normal.
5294 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
5296 // If this is the result, also evaluate the result now.
5297 if (ov == resultExpr) {
5299 result.LV = CGF.EmitLValue(ov);
5301 result.RV = CGF.EmitAnyExpr(ov, slot);
5305 opaques.push_back(opaqueData);
5307 // Otherwise, if the expression is the result, evaluate it
5308 // and remember the result.
5309 } else if (semantic == resultExpr) {
5311 result.LV = CGF.EmitLValue(semantic);
5313 result.RV = CGF.EmitAnyExpr(semantic, slot);
5315 // Otherwise, evaluate the expression in an ignored context.
5317 CGF.EmitIgnoredExpr(semantic);
5321 // Unbind all the opaques now.
5322 for (unsigned i = 0, e = opaques.size(); i != e; ++i)
5323 opaques[i].unbind(CGF);
5328 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E,
5329 AggValueSlot slot) {
5330 return emitPseudoObjectExpr(*this, E, false, slot).RV;
5333 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) {
5334 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV;