1 //===--- CGExpr.cpp - Emit LLVM Code from Expressions ---------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This contains code to emit Expr nodes as LLVM code.
12 //===----------------------------------------------------------------------===//
16 #include "CGCleanup.h"
17 #include "CGDebugInfo.h"
18 #include "CGObjCRuntime.h"
19 #include "CGOpenMPRuntime.h"
20 #include "CGRecordLayout.h"
21 #include "CodeGenFunction.h"
22 #include "CodeGenModule.h"
23 #include "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/Frontend/CodeGenOptions.h"
29 #include "llvm/ADT/Hashing.h"
30 #include "llvm/ADT/StringExtras.h"
31 #include "llvm/IR/DataLayout.h"
32 #include "llvm/IR/Intrinsics.h"
33 #include "llvm/IR/LLVMContext.h"
34 #include "llvm/IR/MDBuilder.h"
35 #include "llvm/Support/ConvertUTF.h"
36 #include "llvm/Support/MathExtras.h"
37 #include "llvm/Support/Path.h"
38 #include "llvm/Transforms/Utils/SanitizerStats.h"
42 using namespace clang;
43 using namespace CodeGen;
45 //===--------------------------------------------------------------------===//
46 // Miscellaneous Helper Methods
47 //===--------------------------------------------------------------------===//
49 llvm::Value *CodeGenFunction::EmitCastToVoidPtr(llvm::Value *value) {
50 unsigned addressSpace =
51 cast<llvm::PointerType>(value->getType())->getAddressSpace();
53 llvm::PointerType *destType = Int8PtrTy;
55 destType = llvm::Type::getInt8PtrTy(getLLVMContext(), addressSpace);
57 if (value->getType() == destType) return value;
58 return Builder.CreateBitCast(value, destType);
61 /// CreateTempAlloca - This creates a alloca and inserts it into the entry
63 Address CodeGenFunction::CreateTempAlloca(llvm::Type *Ty, CharUnits Align,
65 auto Alloca = CreateTempAlloca(Ty, Name);
66 Alloca->setAlignment(Align.getQuantity());
67 return Address(Alloca, Align);
70 /// CreateTempAlloca - This creates a alloca and inserts it into the entry
72 llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty,
74 return new llvm::AllocaInst(Ty, CGM.getDataLayout().getAllocaAddrSpace(),
75 nullptr, Name, AllocaInsertPt);
78 /// CreateDefaultAlignTempAlloca - This creates an alloca with the
79 /// default alignment of the corresponding LLVM type, which is *not*
80 /// guaranteed to be related in any way to the expected alignment of
81 /// an AST type that might have been lowered to Ty.
82 Address CodeGenFunction::CreateDefaultAlignTempAlloca(llvm::Type *Ty,
85 CharUnits::fromQuantity(CGM.getDataLayout().getABITypeAlignment(Ty));
86 return CreateTempAlloca(Ty, Align, Name);
89 void CodeGenFunction::InitTempAlloca(Address Var, llvm::Value *Init) {
90 assert(isa<llvm::AllocaInst>(Var.getPointer()));
91 auto *Store = new llvm::StoreInst(Init, Var.getPointer());
92 Store->setAlignment(Var.getAlignment().getQuantity());
93 llvm::BasicBlock *Block = AllocaInsertPt->getParent();
94 Block->getInstList().insertAfter(AllocaInsertPt->getIterator(), Store);
97 Address CodeGenFunction::CreateIRTemp(QualType Ty, const Twine &Name) {
98 CharUnits Align = getContext().getTypeAlignInChars(Ty);
99 return CreateTempAlloca(ConvertType(Ty), Align, Name);
102 Address CodeGenFunction::CreateMemTemp(QualType Ty, const Twine &Name) {
103 // FIXME: Should we prefer the preferred type alignment here?
104 return CreateMemTemp(Ty, getContext().getTypeAlignInChars(Ty), Name);
107 Address CodeGenFunction::CreateMemTemp(QualType Ty, CharUnits Align,
109 return CreateTempAlloca(ConvertTypeForMem(Ty), Align, Name);
112 /// EvaluateExprAsBool - Perform the usual unary conversions on the specified
113 /// expression and compare the result against zero, returning an Int1Ty value.
114 llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
115 PGO.setCurrentStmt(E);
116 if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) {
117 llvm::Value *MemPtr = EmitScalarExpr(E);
118 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT);
121 QualType BoolTy = getContext().BoolTy;
122 SourceLocation Loc = E->getExprLoc();
123 if (!E->getType()->isAnyComplexType())
124 return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy, Loc);
126 return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(), BoolTy,
130 /// EmitIgnoredExpr - Emit code to compute the specified expression,
131 /// ignoring the result.
132 void CodeGenFunction::EmitIgnoredExpr(const Expr *E) {
134 return (void) EmitAnyExpr(E, AggValueSlot::ignored(), true);
136 // Just emit it as an l-value and drop the result.
140 /// EmitAnyExpr - Emit code to compute the specified expression which
141 /// can have any type. The result is returned as an RValue struct.
142 /// If this is an aggregate expression, AggSlot indicates where the
143 /// result should be returned.
144 RValue CodeGenFunction::EmitAnyExpr(const Expr *E,
145 AggValueSlot aggSlot,
147 switch (getEvaluationKind(E->getType())) {
149 return RValue::get(EmitScalarExpr(E, ignoreResult));
151 return RValue::getComplex(EmitComplexExpr(E, ignoreResult, ignoreResult));
153 if (!ignoreResult && aggSlot.isIgnored())
154 aggSlot = CreateAggTemp(E->getType(), "agg-temp");
155 EmitAggExpr(E, aggSlot);
156 return aggSlot.asRValue();
158 llvm_unreachable("bad evaluation kind");
161 /// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will
162 /// always be accessible even if no aggregate location is provided.
163 RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) {
164 AggValueSlot AggSlot = AggValueSlot::ignored();
166 if (hasAggregateEvaluationKind(E->getType()))
167 AggSlot = CreateAggTemp(E->getType(), "agg.tmp");
168 return EmitAnyExpr(E, AggSlot);
171 /// EmitAnyExprToMem - Evaluate an expression into a given memory
173 void CodeGenFunction::EmitAnyExprToMem(const Expr *E,
177 // FIXME: This function should take an LValue as an argument.
178 switch (getEvaluationKind(E->getType())) {
180 EmitComplexExprIntoLValue(E, MakeAddrLValue(Location, E->getType()),
184 case TEK_Aggregate: {
185 EmitAggExpr(E, AggValueSlot::forAddr(Location, Quals,
186 AggValueSlot::IsDestructed_t(IsInit),
187 AggValueSlot::DoesNotNeedGCBarriers,
188 AggValueSlot::IsAliased_t(!IsInit)));
193 RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false));
194 LValue LV = MakeAddrLValue(Location, E->getType());
195 EmitStoreThroughLValue(RV, LV);
199 llvm_unreachable("bad evaluation kind");
203 pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M,
204 const Expr *E, Address ReferenceTemporary) {
205 // Objective-C++ ARC:
206 // If we are binding a reference to a temporary that has ownership, we
207 // need to perform retain/release operations on the temporary.
209 // FIXME: This should be looking at E, not M.
210 if (auto Lifetime = M->getType().getObjCLifetime()) {
212 case Qualifiers::OCL_None:
213 case Qualifiers::OCL_ExplicitNone:
214 // Carry on to normal cleanup handling.
217 case Qualifiers::OCL_Autoreleasing:
218 // Nothing to do; cleaned up by an autorelease pool.
221 case Qualifiers::OCL_Strong:
222 case Qualifiers::OCL_Weak:
223 switch (StorageDuration Duration = M->getStorageDuration()) {
225 // Note: we intentionally do not register a cleanup to release
226 // the object on program termination.
230 // FIXME: We should probably register a cleanup in this case.
234 case SD_FullExpression:
235 CodeGenFunction::Destroyer *Destroy;
236 CleanupKind CleanupKind;
237 if (Lifetime == Qualifiers::OCL_Strong) {
238 const ValueDecl *VD = M->getExtendingDecl();
240 VD && isa<VarDecl>(VD) && VD->hasAttr<ObjCPreciseLifetimeAttr>();
241 CleanupKind = CGF.getARCCleanupKind();
242 Destroy = Precise ? &CodeGenFunction::destroyARCStrongPrecise
243 : &CodeGenFunction::destroyARCStrongImprecise;
245 // __weak objects always get EH cleanups; otherwise, exceptions
246 // could cause really nasty crashes instead of mere leaks.
247 CleanupKind = NormalAndEHCleanup;
248 Destroy = &CodeGenFunction::destroyARCWeak;
250 if (Duration == SD_FullExpression)
251 CGF.pushDestroy(CleanupKind, ReferenceTemporary,
252 M->getType(), *Destroy,
253 CleanupKind & EHCleanup);
255 CGF.pushLifetimeExtendedDestroy(CleanupKind, ReferenceTemporary,
257 *Destroy, CleanupKind & EHCleanup);
261 llvm_unreachable("temporary cannot have dynamic storage duration");
263 llvm_unreachable("unknown storage duration");
267 CXXDestructorDecl *ReferenceTemporaryDtor = nullptr;
268 if (const RecordType *RT =
269 E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
270 // Get the destructor for the reference temporary.
271 auto *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
272 if (!ClassDecl->hasTrivialDestructor())
273 ReferenceTemporaryDtor = ClassDecl->getDestructor();
276 if (!ReferenceTemporaryDtor)
279 // Call the destructor for the temporary.
280 switch (M->getStorageDuration()) {
283 llvm::Constant *CleanupFn;
284 llvm::Constant *CleanupArg;
285 if (E->getType()->isArrayType()) {
286 CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper(
287 ReferenceTemporary, E->getType(),
288 CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions,
289 dyn_cast_or_null<VarDecl>(M->getExtendingDecl()));
290 CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy);
292 CleanupFn = CGF.CGM.getAddrOfCXXStructor(ReferenceTemporaryDtor,
293 StructorType::Complete);
294 CleanupArg = cast<llvm::Constant>(ReferenceTemporary.getPointer());
296 CGF.CGM.getCXXABI().registerGlobalDtor(
297 CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg);
301 case SD_FullExpression:
302 CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(),
303 CodeGenFunction::destroyCXXObject,
304 CGF.getLangOpts().Exceptions);
308 CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup,
309 ReferenceTemporary, E->getType(),
310 CodeGenFunction::destroyCXXObject,
311 CGF.getLangOpts().Exceptions);
315 llvm_unreachable("temporary cannot have dynamic storage duration");
320 createReferenceTemporary(CodeGenFunction &CGF,
321 const MaterializeTemporaryExpr *M, const Expr *Inner) {
322 switch (M->getStorageDuration()) {
323 case SD_FullExpression:
325 // If we have a constant temporary array or record try to promote it into a
326 // constant global under the same rules a normal constant would've been
327 // promoted. This is easier on the optimizer and generally emits fewer
329 QualType Ty = Inner->getType();
330 if (CGF.CGM.getCodeGenOpts().MergeAllConstants &&
331 (Ty->isArrayType() || Ty->isRecordType()) &&
332 CGF.CGM.isTypeConstant(Ty, true))
333 if (llvm::Constant *Init = CGF.CGM.EmitConstantExpr(Inner, Ty, &CGF)) {
334 auto *GV = new llvm::GlobalVariable(
335 CGF.CGM.getModule(), Init->getType(), /*isConstant=*/true,
336 llvm::GlobalValue::PrivateLinkage, Init, ".ref.tmp");
337 CharUnits alignment = CGF.getContext().getTypeAlignInChars(Ty);
338 GV->setAlignment(alignment.getQuantity());
339 // FIXME: Should we put the new global into a COMDAT?
340 return Address(GV, alignment);
342 return CGF.CreateMemTemp(Ty, "ref.tmp");
346 return CGF.CGM.GetAddrOfGlobalTemporary(M, Inner);
349 llvm_unreachable("temporary can't have dynamic storage duration");
351 llvm_unreachable("unknown storage duration");
354 LValue CodeGenFunction::
355 EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) {
356 const Expr *E = M->GetTemporaryExpr();
358 // FIXME: ideally this would use EmitAnyExprToMem, however, we cannot do so
359 // as that will cause the lifetime adjustment to be lost for ARC
360 auto ownership = M->getType().getObjCLifetime();
361 if (ownership != Qualifiers::OCL_None &&
362 ownership != Qualifiers::OCL_ExplicitNone) {
363 Address Object = createReferenceTemporary(*this, M, E);
364 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) {
365 Object = Address(llvm::ConstantExpr::getBitCast(Var,
366 ConvertTypeForMem(E->getType())
367 ->getPointerTo(Object.getAddressSpace())),
368 Object.getAlignment());
370 // createReferenceTemporary will promote the temporary to a global with a
371 // constant initializer if it can. It can only do this to a value of
372 // ARC-manageable type if the value is global and therefore "immune" to
373 // ref-counting operations. Therefore we have no need to emit either a
374 // dynamic initialization or a cleanup and we can just return the address
376 if (Var->hasInitializer())
377 return MakeAddrLValue(Object, M->getType(),
378 LValueBaseInfo(AlignmentSource::Decl, false));
380 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
382 LValue RefTempDst = MakeAddrLValue(Object, M->getType(),
383 LValueBaseInfo(AlignmentSource::Decl,
386 switch (getEvaluationKind(E->getType())) {
387 default: llvm_unreachable("expected scalar or aggregate expression");
389 EmitScalarInit(E, M->getExtendingDecl(), RefTempDst, false);
391 case TEK_Aggregate: {
392 EmitAggExpr(E, AggValueSlot::forAddr(Object,
393 E->getType().getQualifiers(),
394 AggValueSlot::IsDestructed,
395 AggValueSlot::DoesNotNeedGCBarriers,
396 AggValueSlot::IsNotAliased));
401 pushTemporaryCleanup(*this, M, E, Object);
405 SmallVector<const Expr *, 2> CommaLHSs;
406 SmallVector<SubobjectAdjustment, 2> Adjustments;
407 E = E->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
409 for (const auto &Ignored : CommaLHSs)
410 EmitIgnoredExpr(Ignored);
412 if (const auto *opaque = dyn_cast<OpaqueValueExpr>(E)) {
413 if (opaque->getType()->isRecordType()) {
414 assert(Adjustments.empty());
415 return EmitOpaqueValueLValue(opaque);
419 // Create and initialize the reference temporary.
420 Address Object = createReferenceTemporary(*this, M, E);
421 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) {
422 Object = Address(llvm::ConstantExpr::getBitCast(
423 Var, ConvertTypeForMem(E->getType())->getPointerTo()),
424 Object.getAlignment());
425 // If the temporary is a global and has a constant initializer or is a
426 // constant temporary that we promoted to a global, we may have already
428 if (!Var->hasInitializer()) {
429 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
430 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
433 switch (M->getStorageDuration()) {
435 case SD_FullExpression:
436 if (auto *Size = EmitLifetimeStart(
437 CGM.getDataLayout().getTypeAllocSize(Object.getElementType()),
438 Object.getPointer())) {
439 if (M->getStorageDuration() == SD_Automatic)
440 pushCleanupAfterFullExpr<CallLifetimeEnd>(NormalEHLifetimeMarker,
443 pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Object,
450 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
452 pushTemporaryCleanup(*this, M, E, Object);
454 // Perform derived-to-base casts and/or field accesses, to get from the
455 // temporary object we created (and, potentially, for which we extended
456 // the lifetime) to the subobject we're binding the reference to.
457 for (unsigned I = Adjustments.size(); I != 0; --I) {
458 SubobjectAdjustment &Adjustment = Adjustments[I-1];
459 switch (Adjustment.Kind) {
460 case SubobjectAdjustment::DerivedToBaseAdjustment:
462 GetAddressOfBaseClass(Object, Adjustment.DerivedToBase.DerivedClass,
463 Adjustment.DerivedToBase.BasePath->path_begin(),
464 Adjustment.DerivedToBase.BasePath->path_end(),
465 /*NullCheckValue=*/ false, E->getExprLoc());
468 case SubobjectAdjustment::FieldAdjustment: {
469 LValue LV = MakeAddrLValue(Object, E->getType(),
470 LValueBaseInfo(AlignmentSource::Decl, false));
471 LV = EmitLValueForField(LV, Adjustment.Field);
472 assert(LV.isSimple() &&
473 "materialized temporary field is not a simple lvalue");
474 Object = LV.getAddress();
478 case SubobjectAdjustment::MemberPointerAdjustment: {
479 llvm::Value *Ptr = EmitScalarExpr(Adjustment.Ptr.RHS);
480 Object = EmitCXXMemberDataPointerAddress(E, Object, Ptr,
487 return MakeAddrLValue(Object, M->getType(),
488 LValueBaseInfo(AlignmentSource::Decl, false));
492 CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E) {
493 // Emit the expression as an lvalue.
494 LValue LV = EmitLValue(E);
495 assert(LV.isSimple());
496 llvm::Value *Value = LV.getPointer();
498 if (sanitizePerformTypeCheck() && !E->getType()->isFunctionType()) {
499 // C++11 [dcl.ref]p5 (as amended by core issue 453):
500 // If a glvalue to which a reference is directly bound designates neither
501 // an existing object or function of an appropriate type nor a region of
502 // storage of suitable size and alignment to contain an object of the
503 // reference's type, the behavior is undefined.
504 QualType Ty = E->getType();
505 EmitTypeCheck(TCK_ReferenceBinding, E->getExprLoc(), Value, Ty);
508 return RValue::get(Value);
512 /// getAccessedFieldNo - Given an encoded value and a result number, return the
513 /// input field number being accessed.
514 unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
515 const llvm::Constant *Elts) {
516 return cast<llvm::ConstantInt>(Elts->getAggregateElement(Idx))
520 /// Emit the hash_16_bytes function from include/llvm/ADT/Hashing.h.
521 static llvm::Value *emitHash16Bytes(CGBuilderTy &Builder, llvm::Value *Low,
523 llvm::Value *KMul = Builder.getInt64(0x9ddfea08eb382d69ULL);
524 llvm::Value *K47 = Builder.getInt64(47);
525 llvm::Value *A0 = Builder.CreateMul(Builder.CreateXor(Low, High), KMul);
526 llvm::Value *A1 = Builder.CreateXor(Builder.CreateLShr(A0, K47), A0);
527 llvm::Value *B0 = Builder.CreateMul(Builder.CreateXor(High, A1), KMul);
528 llvm::Value *B1 = Builder.CreateXor(Builder.CreateLShr(B0, K47), B0);
529 return Builder.CreateMul(B1, KMul);
532 bool CodeGenFunction::sanitizePerformTypeCheck() const {
533 return SanOpts.has(SanitizerKind::Null) |
534 SanOpts.has(SanitizerKind::Alignment) |
535 SanOpts.has(SanitizerKind::ObjectSize) |
536 SanOpts.has(SanitizerKind::Vptr);
539 void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc,
540 llvm::Value *Ptr, QualType Ty,
542 SanitizerSet SkippedChecks) {
543 if (!sanitizePerformTypeCheck())
546 // Don't check pointers outside the default address space. The null check
547 // isn't correct, the object-size check isn't supported by LLVM, and we can't
548 // communicate the addresses to the runtime handler for the vptr check.
549 if (Ptr->getType()->getPointerAddressSpace())
552 // Don't check pointers to volatile data. The behavior here is implementation-
554 if (Ty.isVolatileQualified())
557 SanitizerScope SanScope(this);
559 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 3> Checks;
560 llvm::BasicBlock *Done = nullptr;
562 // Quickly determine whether we have a pointer to an alloca. It's possible
563 // to skip null checks, and some alignment checks, for these pointers. This
564 // can reduce compile-time significantly.
566 dyn_cast<llvm::AllocaInst>(Ptr->stripPointerCastsNoFollowAliases());
568 bool AllowNullPointers = TCK == TCK_DowncastPointer || TCK == TCK_Upcast ||
569 TCK == TCK_UpcastToVirtualBase;
570 if ((SanOpts.has(SanitizerKind::Null) || AllowNullPointers) &&
571 !SkippedChecks.has(SanitizerKind::Null) && !PtrToAlloca) {
572 // The glvalue must not be an empty glvalue.
573 llvm::Value *IsNonNull = Builder.CreateIsNotNull(Ptr);
575 // The IR builder can constant-fold the null check if the pointer points to
578 IsNonNull == llvm::ConstantInt::getTrue(getLLVMContext());
580 // Skip the null check if the pointer is known to be non-null.
582 if (AllowNullPointers) {
583 // When performing pointer casts, it's OK if the value is null.
584 // Skip the remaining checks in that case.
585 Done = createBasicBlock("null");
586 llvm::BasicBlock *Rest = createBasicBlock("not.null");
587 Builder.CreateCondBr(IsNonNull, Rest, Done);
590 Checks.push_back(std::make_pair(IsNonNull, SanitizerKind::Null));
595 if (SanOpts.has(SanitizerKind::ObjectSize) &&
596 !SkippedChecks.has(SanitizerKind::ObjectSize) &&
597 !Ty->isIncompleteType()) {
598 uint64_t Size = getContext().getTypeSizeInChars(Ty).getQuantity();
600 // The glvalue must refer to a large enough storage region.
601 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation
603 // FIXME: Get object address space
604 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy };
605 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys);
606 llvm::Value *Min = Builder.getFalse();
607 llvm::Value *NullIsUnknown = Builder.getFalse();
608 llvm::Value *CastAddr = Builder.CreateBitCast(Ptr, Int8PtrTy);
609 llvm::Value *LargeEnough = Builder.CreateICmpUGE(
610 Builder.CreateCall(F, {CastAddr, Min, NullIsUnknown}),
611 llvm::ConstantInt::get(IntPtrTy, Size));
612 Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize));
615 uint64_t AlignVal = 0;
617 if (SanOpts.has(SanitizerKind::Alignment) &&
618 !SkippedChecks.has(SanitizerKind::Alignment)) {
619 AlignVal = Alignment.getQuantity();
620 if (!Ty->isIncompleteType() && !AlignVal)
621 AlignVal = getContext().getTypeAlignInChars(Ty).getQuantity();
623 // The glvalue must be suitably aligned.
625 (!PtrToAlloca || PtrToAlloca->getAlignment() < AlignVal)) {
627 Builder.CreateAnd(Builder.CreatePtrToInt(Ptr, IntPtrTy),
628 llvm::ConstantInt::get(IntPtrTy, AlignVal - 1));
629 llvm::Value *Aligned =
630 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0));
631 Checks.push_back(std::make_pair(Aligned, SanitizerKind::Alignment));
635 if (Checks.size() > 0) {
636 // Make sure we're not losing information. Alignment needs to be a power of
638 assert(!AlignVal || (uint64_t)1 << llvm::Log2_64(AlignVal) == AlignVal);
639 llvm::Constant *StaticData[] = {
640 EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(Ty),
641 llvm::ConstantInt::get(Int8Ty, AlignVal ? llvm::Log2_64(AlignVal) : 1),
642 llvm::ConstantInt::get(Int8Ty, TCK)};
643 EmitCheck(Checks, SanitizerHandler::TypeMismatch, StaticData, Ptr);
646 // If possible, check that the vptr indicates that there is a subobject of
647 // type Ty at offset zero within this object.
649 // C++11 [basic.life]p5,6:
650 // [For storage which does not refer to an object within its lifetime]
651 // The program has undefined behavior if:
652 // -- the [pointer or glvalue] is used to access a non-static data member
653 // or call a non-static member function
654 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
655 if (SanOpts.has(SanitizerKind::Vptr) &&
656 !SkippedChecks.has(SanitizerKind::Vptr) &&
657 (TCK == TCK_MemberAccess || TCK == TCK_MemberCall ||
658 TCK == TCK_DowncastPointer || TCK == TCK_DowncastReference ||
659 TCK == TCK_UpcastToVirtualBase) &&
660 RD && RD->hasDefinition() && RD->isDynamicClass()) {
661 // Compute a hash of the mangled name of the type.
663 // FIXME: This is not guaranteed to be deterministic! Move to a
664 // fingerprinting mechanism once LLVM provides one. For the time
665 // being the implementation happens to be deterministic.
666 SmallString<64> MangledName;
667 llvm::raw_svector_ostream Out(MangledName);
668 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(),
671 // Blacklist based on the mangled type.
672 if (!CGM.getContext().getSanitizerBlacklist().isBlacklistedType(
674 llvm::hash_code TypeHash = hash_value(Out.str());
676 // Load the vptr, and compute hash_16_bytes(TypeHash, vptr).
677 llvm::Value *Low = llvm::ConstantInt::get(Int64Ty, TypeHash);
678 llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0);
679 Address VPtrAddr(Builder.CreateBitCast(Ptr, VPtrTy), getPointerAlign());
680 llvm::Value *VPtrVal = Builder.CreateLoad(VPtrAddr);
681 llvm::Value *High = Builder.CreateZExt(VPtrVal, Int64Ty);
683 llvm::Value *Hash = emitHash16Bytes(Builder, Low, High);
684 Hash = Builder.CreateTrunc(Hash, IntPtrTy);
686 // Look the hash up in our cache.
687 const int CacheSize = 128;
688 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize);
689 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable,
690 "__ubsan_vptr_type_cache");
691 llvm::Value *Slot = Builder.CreateAnd(Hash,
692 llvm::ConstantInt::get(IntPtrTy,
694 llvm::Value *Indices[] = { Builder.getInt32(0), Slot };
695 llvm::Value *CacheVal =
696 Builder.CreateAlignedLoad(Builder.CreateInBoundsGEP(Cache, Indices),
699 // If the hash isn't in the cache, call a runtime handler to perform the
700 // hard work of checking whether the vptr is for an object of the right
701 // type. This will either fill in the cache and return, or produce a
703 llvm::Value *EqualHash = Builder.CreateICmpEQ(CacheVal, Hash);
704 llvm::Constant *StaticData[] = {
705 EmitCheckSourceLocation(Loc),
706 EmitCheckTypeDescriptor(Ty),
707 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()),
708 llvm::ConstantInt::get(Int8Ty, TCK)
710 llvm::Value *DynamicData[] = { Ptr, Hash };
711 EmitCheck(std::make_pair(EqualHash, SanitizerKind::Vptr),
712 SanitizerHandler::DynamicTypeCacheMiss, StaticData,
718 Builder.CreateBr(Done);
723 /// Determine whether this expression refers to a flexible array member in a
724 /// struct. We disable array bounds checks for such members.
725 static bool isFlexibleArrayMemberExpr(const Expr *E) {
726 // For compatibility with existing code, we treat arrays of length 0 or
727 // 1 as flexible array members.
728 const ArrayType *AT = E->getType()->castAsArrayTypeUnsafe();
729 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT)) {
730 if (CAT->getSize().ugt(1))
732 } else if (!isa<IncompleteArrayType>(AT))
735 E = E->IgnoreParens();
737 // A flexible array member must be the last member in the class.
738 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
739 // FIXME: If the base type of the member expr is not FD->getParent(),
740 // this should not be treated as a flexible array member access.
741 if (const auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
742 RecordDecl::field_iterator FI(
743 DeclContext::decl_iterator(const_cast<FieldDecl *>(FD)));
744 return ++FI == FD->getParent()->field_end();
746 } else if (const auto *IRE = dyn_cast<ObjCIvarRefExpr>(E)) {
747 return IRE->getDecl()->getNextIvar() == nullptr;
753 /// If Base is known to point to the start of an array, return the length of
754 /// that array. Return 0 if the length cannot be determined.
755 static llvm::Value *getArrayIndexingBound(
756 CodeGenFunction &CGF, const Expr *Base, QualType &IndexedType) {
757 // For the vector indexing extension, the bound is the number of elements.
758 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) {
759 IndexedType = Base->getType();
760 return CGF.Builder.getInt32(VT->getNumElements());
763 Base = Base->IgnoreParens();
765 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
766 if (CE->getCastKind() == CK_ArrayToPointerDecay &&
767 !isFlexibleArrayMemberExpr(CE->getSubExpr())) {
768 IndexedType = CE->getSubExpr()->getType();
769 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe();
770 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT))
771 return CGF.Builder.getInt(CAT->getSize());
772 else if (const auto *VAT = dyn_cast<VariableArrayType>(AT))
773 return CGF.getVLASize(VAT).first;
780 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base,
781 llvm::Value *Index, QualType IndexType,
783 assert(SanOpts.has(SanitizerKind::ArrayBounds) &&
784 "should not be called unless adding bounds checks");
785 SanitizerScope SanScope(this);
787 QualType IndexedType;
788 llvm::Value *Bound = getArrayIndexingBound(*this, Base, IndexedType);
792 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType();
793 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned);
794 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false);
796 llvm::Constant *StaticData[] = {
797 EmitCheckSourceLocation(E->getExprLoc()),
798 EmitCheckTypeDescriptor(IndexedType),
799 EmitCheckTypeDescriptor(IndexType)
801 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal)
802 : Builder.CreateICmpULE(IndexVal, BoundVal);
803 EmitCheck(std::make_pair(Check, SanitizerKind::ArrayBounds),
804 SanitizerHandler::OutOfBounds, StaticData, Index);
808 CodeGenFunction::ComplexPairTy CodeGenFunction::
809 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
810 bool isInc, bool isPre) {
811 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc());
813 llvm::Value *NextVal;
814 if (isa<llvm::IntegerType>(InVal.first->getType())) {
815 uint64_t AmountVal = isInc ? 1 : -1;
816 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
818 // Add the inc/dec to the real part.
819 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
821 QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
822 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
825 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
827 // Add the inc/dec to the real part.
828 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
831 ComplexPairTy IncVal(NextVal, InVal.second);
833 // Store the updated result through the lvalue.
834 EmitStoreOfComplex(IncVal, LV, /*init*/ false);
836 // If this is a postinc, return the value read from memory, otherwise use the
838 return isPre ? IncVal : InVal;
841 void CodeGenModule::EmitExplicitCastExprType(const ExplicitCastExpr *E,
842 CodeGenFunction *CGF) {
843 // Bind VLAs in the cast type.
844 if (CGF && E->getType()->isVariablyModifiedType())
845 CGF->EmitVariablyModifiedType(E->getType());
847 if (CGDebugInfo *DI = getModuleDebugInfo())
848 DI->EmitExplicitCastType(E->getType());
851 //===----------------------------------------------------------------------===//
852 // LValue Expression Emission
853 //===----------------------------------------------------------------------===//
855 /// EmitPointerWithAlignment - Given an expression of pointer type, try to
856 /// derive a more accurate bound on the alignment of the pointer.
857 Address CodeGenFunction::EmitPointerWithAlignment(const Expr *E,
858 LValueBaseInfo *BaseInfo) {
859 // We allow this with ObjC object pointers because of fragile ABIs.
860 assert(E->getType()->isPointerType() ||
861 E->getType()->isObjCObjectPointerType());
862 E = E->IgnoreParens();
865 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
866 if (const auto *ECE = dyn_cast<ExplicitCastExpr>(CE))
867 CGM.EmitExplicitCastExprType(ECE, this);
869 switch (CE->getCastKind()) {
870 // Non-converting casts (but not C's implicit conversion from void*).
873 if (auto PtrTy = CE->getSubExpr()->getType()->getAs<PointerType>()) {
874 if (PtrTy->getPointeeType()->isVoidType())
877 LValueBaseInfo InnerInfo;
878 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(), &InnerInfo);
879 if (BaseInfo) *BaseInfo = InnerInfo;
881 // If this is an explicit bitcast, and the source l-value is
882 // opaque, honor the alignment of the casted-to type.
883 if (isa<ExplicitCastExpr>(CE) &&
884 InnerInfo.getAlignmentSource() != AlignmentSource::Decl) {
885 LValueBaseInfo ExpInfo;
886 CharUnits Align = getNaturalPointeeTypeAlignment(E->getType(),
889 BaseInfo->mergeForCast(ExpInfo);
890 Addr = Address(Addr.getPointer(), Align);
893 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast) &&
894 CE->getCastKind() == CK_BitCast) {
895 if (auto PT = E->getType()->getAs<PointerType>())
896 EmitVTablePtrCheckForCast(PT->getPointeeType(), Addr.getPointer(),
898 CodeGenFunction::CFITCK_UnrelatedCast,
902 return Builder.CreateBitCast(Addr, ConvertType(E->getType()));
906 // Array-to-pointer decay.
907 case CK_ArrayToPointerDecay:
908 return EmitArrayToPointerDecay(CE->getSubExpr(), BaseInfo);
910 // Derived-to-base conversions.
911 case CK_UncheckedDerivedToBase:
912 case CK_DerivedToBase: {
913 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(), BaseInfo);
914 auto Derived = CE->getSubExpr()->getType()->getPointeeCXXRecordDecl();
915 return GetAddressOfBaseClass(Addr, Derived,
916 CE->path_begin(), CE->path_end(),
917 ShouldNullCheckClassCastValue(CE),
921 // TODO: Is there any reason to treat base-to-derived conversions
929 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
930 if (UO->getOpcode() == UO_AddrOf) {
931 LValue LV = EmitLValue(UO->getSubExpr());
932 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
933 return LV.getAddress();
937 // TODO: conditional operators, comma.
939 // Otherwise, use the alignment of the type.
940 CharUnits Align = getNaturalPointeeTypeAlignment(E->getType(), BaseInfo);
941 return Address(EmitScalarExpr(E), Align);
944 RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
945 if (Ty->isVoidType())
946 return RValue::get(nullptr);
948 switch (getEvaluationKind(Ty)) {
951 ConvertType(Ty->castAs<ComplexType>()->getElementType());
952 llvm::Value *U = llvm::UndefValue::get(EltTy);
953 return RValue::getComplex(std::make_pair(U, U));
956 // If this is a use of an undefined aggregate type, the aggregate must have an
957 // identifiable address. Just because the contents of the value are undefined
958 // doesn't mean that the address can't be taken and compared.
959 case TEK_Aggregate: {
960 Address DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
961 return RValue::getAggregate(DestPtr);
965 return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
967 llvm_unreachable("bad evaluation kind");
970 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
972 ErrorUnsupported(E, Name);
973 return GetUndefRValue(E->getType());
976 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
978 ErrorUnsupported(E, Name);
979 llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
980 return MakeAddrLValue(Address(llvm::UndefValue::get(Ty), CharUnits::One()),
984 bool CodeGenFunction::IsWrappedCXXThis(const Expr *Obj) {
985 const Expr *Base = Obj;
986 while (!isa<CXXThisExpr>(Base)) {
987 // The result of a dynamic_cast can be null.
988 if (isa<CXXDynamicCastExpr>(Base))
991 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
992 Base = CE->getSubExpr();
993 } else if (const auto *PE = dyn_cast<ParenExpr>(Base)) {
994 Base = PE->getSubExpr();
995 } else if (const auto *UO = dyn_cast<UnaryOperator>(Base)) {
996 if (UO->getOpcode() == UO_Extension)
997 Base = UO->getSubExpr();
1007 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) {
1009 if (SanOpts.has(SanitizerKind::ArrayBounds) && isa<ArraySubscriptExpr>(E))
1010 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true);
1013 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) {
1014 SanitizerSet SkippedChecks;
1015 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
1016 bool IsBaseCXXThis = IsWrappedCXXThis(ME->getBase());
1018 SkippedChecks.set(SanitizerKind::Alignment, true);
1019 if (IsBaseCXXThis || isa<DeclRefExpr>(ME->getBase()))
1020 SkippedChecks.set(SanitizerKind::Null, true);
1022 EmitTypeCheck(TCK, E->getExprLoc(), LV.getPointer(),
1023 E->getType(), LV.getAlignment(), SkippedChecks);
1028 /// EmitLValue - Emit code to compute a designator that specifies the location
1029 /// of the expression.
1031 /// This can return one of two things: a simple address or a bitfield reference.
1032 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be
1033 /// an LLVM pointer type.
1035 /// If this returns a bitfield reference, nothing about the pointee type of the
1036 /// LLVM value is known: For example, it may not be a pointer to an integer.
1038 /// If this returns a normal address, and if the lvalue's C type is fixed size,
1039 /// this method guarantees that the returned pointer type will point to an LLVM
1040 /// type of the same size of the lvalue's type. If the lvalue has a variable
1041 /// length type, this is not possible.
1043 LValue CodeGenFunction::EmitLValue(const Expr *E) {
1044 ApplyDebugLocation DL(*this, E);
1045 switch (E->getStmtClass()) {
1046 default: return EmitUnsupportedLValue(E, "l-value expression");
1048 case Expr::ObjCPropertyRefExprClass:
1049 llvm_unreachable("cannot emit a property reference directly");
1051 case Expr::ObjCSelectorExprClass:
1052 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
1053 case Expr::ObjCIsaExprClass:
1054 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
1055 case Expr::BinaryOperatorClass:
1056 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
1057 case Expr::CompoundAssignOperatorClass: {
1058 QualType Ty = E->getType();
1059 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1060 Ty = AT->getValueType();
1061 if (!Ty->isAnyComplexType())
1062 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1063 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1065 case Expr::CallExprClass:
1066 case Expr::CXXMemberCallExprClass:
1067 case Expr::CXXOperatorCallExprClass:
1068 case Expr::UserDefinedLiteralClass:
1069 return EmitCallExprLValue(cast<CallExpr>(E));
1070 case Expr::VAArgExprClass:
1071 return EmitVAArgExprLValue(cast<VAArgExpr>(E));
1072 case Expr::DeclRefExprClass:
1073 return EmitDeclRefLValue(cast<DeclRefExpr>(E));
1074 case Expr::ParenExprClass:
1075 return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
1076 case Expr::GenericSelectionExprClass:
1077 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr());
1078 case Expr::PredefinedExprClass:
1079 return EmitPredefinedLValue(cast<PredefinedExpr>(E));
1080 case Expr::StringLiteralClass:
1081 return EmitStringLiteralLValue(cast<StringLiteral>(E));
1082 case Expr::ObjCEncodeExprClass:
1083 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
1084 case Expr::PseudoObjectExprClass:
1085 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E));
1086 case Expr::InitListExprClass:
1087 return EmitInitListLValue(cast<InitListExpr>(E));
1088 case Expr::CXXTemporaryObjectExprClass:
1089 case Expr::CXXConstructExprClass:
1090 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
1091 case Expr::CXXBindTemporaryExprClass:
1092 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
1093 case Expr::CXXUuidofExprClass:
1094 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E));
1095 case Expr::LambdaExprClass:
1096 return EmitLambdaLValue(cast<LambdaExpr>(E));
1098 case Expr::ExprWithCleanupsClass: {
1099 const auto *cleanups = cast<ExprWithCleanups>(E);
1100 enterFullExpression(cleanups);
1101 RunCleanupsScope Scope(*this);
1102 LValue LV = EmitLValue(cleanups->getSubExpr());
1103 if (LV.isSimple()) {
1104 // Defend against branches out of gnu statement expressions surrounded by
1106 llvm::Value *V = LV.getPointer();
1107 Scope.ForceCleanup({&V});
1108 return LValue::MakeAddr(Address(V, LV.getAlignment()), LV.getType(),
1109 getContext(), LV.getBaseInfo(),
1112 // FIXME: Is it possible to create an ExprWithCleanups that produces a
1113 // bitfield lvalue or some other non-simple lvalue?
1117 case Expr::CXXDefaultArgExprClass:
1118 return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr());
1119 case Expr::CXXDefaultInitExprClass: {
1120 CXXDefaultInitExprScope Scope(*this);
1121 return EmitLValue(cast<CXXDefaultInitExpr>(E)->getExpr());
1123 case Expr::CXXTypeidExprClass:
1124 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
1126 case Expr::ObjCMessageExprClass:
1127 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
1128 case Expr::ObjCIvarRefExprClass:
1129 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
1130 case Expr::StmtExprClass:
1131 return EmitStmtExprLValue(cast<StmtExpr>(E));
1132 case Expr::UnaryOperatorClass:
1133 return EmitUnaryOpLValue(cast<UnaryOperator>(E));
1134 case Expr::ArraySubscriptExprClass:
1135 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
1136 case Expr::OMPArraySectionExprClass:
1137 return EmitOMPArraySectionExpr(cast<OMPArraySectionExpr>(E));
1138 case Expr::ExtVectorElementExprClass:
1139 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
1140 case Expr::MemberExprClass:
1141 return EmitMemberExpr(cast<MemberExpr>(E));
1142 case Expr::CompoundLiteralExprClass:
1143 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
1144 case Expr::ConditionalOperatorClass:
1145 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
1146 case Expr::BinaryConditionalOperatorClass:
1147 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
1148 case Expr::ChooseExprClass:
1149 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr());
1150 case Expr::OpaqueValueExprClass:
1151 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
1152 case Expr::SubstNonTypeTemplateParmExprClass:
1153 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement());
1154 case Expr::ImplicitCastExprClass:
1155 case Expr::CStyleCastExprClass:
1156 case Expr::CXXFunctionalCastExprClass:
1157 case Expr::CXXStaticCastExprClass:
1158 case Expr::CXXDynamicCastExprClass:
1159 case Expr::CXXReinterpretCastExprClass:
1160 case Expr::CXXConstCastExprClass:
1161 case Expr::ObjCBridgedCastExprClass:
1162 return EmitCastLValue(cast<CastExpr>(E));
1164 case Expr::MaterializeTemporaryExprClass:
1165 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E));
1167 case Expr::CoawaitExprClass:
1168 return EmitCoawaitLValue(cast<CoawaitExpr>(E));
1169 case Expr::CoyieldExprClass:
1170 return EmitCoyieldLValue(cast<CoyieldExpr>(E));
1174 /// Given an object of the given canonical type, can we safely copy a
1175 /// value out of it based on its initializer?
1176 static bool isConstantEmittableObjectType(QualType type) {
1177 assert(type.isCanonical());
1178 assert(!type->isReferenceType());
1180 // Must be const-qualified but non-volatile.
1181 Qualifiers qs = type.getLocalQualifiers();
1182 if (!qs.hasConst() || qs.hasVolatile()) return false;
1184 // Otherwise, all object types satisfy this except C++ classes with
1185 // mutable subobjects or non-trivial copy/destroy behavior.
1186 if (const auto *RT = dyn_cast<RecordType>(type))
1187 if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
1188 if (RD->hasMutableFields() || !RD->isTrivial())
1194 /// Can we constant-emit a load of a reference to a variable of the
1195 /// given type? This is different from predicates like
1196 /// Decl::isUsableInConstantExpressions because we do want it to apply
1197 /// in situations that don't necessarily satisfy the language's rules
1198 /// for this (e.g. C++'s ODR-use rules). For example, we want to able
1199 /// to do this with const float variables even if those variables
1200 /// aren't marked 'constexpr'.
1201 enum ConstantEmissionKind {
1203 CEK_AsReferenceOnly,
1204 CEK_AsValueOrReference,
1207 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) {
1208 type = type.getCanonicalType();
1209 if (const auto *ref = dyn_cast<ReferenceType>(type)) {
1210 if (isConstantEmittableObjectType(ref->getPointeeType()))
1211 return CEK_AsValueOrReference;
1212 return CEK_AsReferenceOnly;
1214 if (isConstantEmittableObjectType(type))
1215 return CEK_AsValueOnly;
1219 /// Try to emit a reference to the given value without producing it as
1220 /// an l-value. This is actually more than an optimization: we can't
1221 /// produce an l-value for variables that we never actually captured
1222 /// in a block or lambda, which means const int variables or constexpr
1223 /// literals or similar.
1224 CodeGenFunction::ConstantEmission
1225 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) {
1226 ValueDecl *value = refExpr->getDecl();
1228 // The value needs to be an enum constant or a constant variable.
1229 ConstantEmissionKind CEK;
1230 if (isa<ParmVarDecl>(value)) {
1232 } else if (auto *var = dyn_cast<VarDecl>(value)) {
1233 CEK = checkVarTypeForConstantEmission(var->getType());
1234 } else if (isa<EnumConstantDecl>(value)) {
1235 CEK = CEK_AsValueOnly;
1239 if (CEK == CEK_None) return ConstantEmission();
1241 Expr::EvalResult result;
1242 bool resultIsReference;
1243 QualType resultType;
1245 // It's best to evaluate all the way as an r-value if that's permitted.
1246 if (CEK != CEK_AsReferenceOnly &&
1247 refExpr->EvaluateAsRValue(result, getContext())) {
1248 resultIsReference = false;
1249 resultType = refExpr->getType();
1251 // Otherwise, try to evaluate as an l-value.
1252 } else if (CEK != CEK_AsValueOnly &&
1253 refExpr->EvaluateAsLValue(result, getContext())) {
1254 resultIsReference = true;
1255 resultType = value->getType();
1259 return ConstantEmission();
1262 // In any case, if the initializer has side-effects, abandon ship.
1263 if (result.HasSideEffects)
1264 return ConstantEmission();
1266 // Emit as a constant.
1267 llvm::Constant *C = CGM.EmitConstantValue(result.Val, resultType, this);
1269 // Make sure we emit a debug reference to the global variable.
1270 // This should probably fire even for
1271 if (isa<VarDecl>(value)) {
1272 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value)))
1273 EmitDeclRefExprDbgValue(refExpr, result.Val);
1275 assert(isa<EnumConstantDecl>(value));
1276 EmitDeclRefExprDbgValue(refExpr, result.Val);
1279 // If we emitted a reference constant, we need to dereference that.
1280 if (resultIsReference)
1281 return ConstantEmission::forReference(C);
1283 return ConstantEmission::forValue(C);
1286 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue,
1287 SourceLocation Loc) {
1288 return EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatile(),
1289 lvalue.getType(), Loc, lvalue.getBaseInfo(),
1290 lvalue.getTBAAInfo(),
1291 lvalue.getTBAABaseType(), lvalue.getTBAAOffset(),
1292 lvalue.isNontemporal());
1295 static bool hasBooleanRepresentation(QualType Ty) {
1296 if (Ty->isBooleanType())
1299 if (const EnumType *ET = Ty->getAs<EnumType>())
1300 return ET->getDecl()->getIntegerType()->isBooleanType();
1302 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1303 return hasBooleanRepresentation(AT->getValueType());
1308 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty,
1309 llvm::APInt &Min, llvm::APInt &End,
1310 bool StrictEnums, bool IsBool) {
1311 const EnumType *ET = Ty->getAs<EnumType>();
1312 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums &&
1313 ET && !ET->getDecl()->isFixed();
1314 if (!IsBool && !IsRegularCPlusPlusEnum)
1318 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0);
1319 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2);
1321 const EnumDecl *ED = ET->getDecl();
1322 llvm::Type *LTy = CGF.ConvertTypeForMem(ED->getIntegerType());
1323 unsigned Bitwidth = LTy->getScalarSizeInBits();
1324 unsigned NumNegativeBits = ED->getNumNegativeBits();
1325 unsigned NumPositiveBits = ED->getNumPositiveBits();
1327 if (NumNegativeBits) {
1328 unsigned NumBits = std::max(NumNegativeBits, NumPositiveBits + 1);
1329 assert(NumBits <= Bitwidth);
1330 End = llvm::APInt(Bitwidth, 1) << (NumBits - 1);
1333 assert(NumPositiveBits <= Bitwidth);
1334 End = llvm::APInt(Bitwidth, 1) << NumPositiveBits;
1335 Min = llvm::APInt(Bitwidth, 0);
1341 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) {
1342 llvm::APInt Min, End;
1343 if (!getRangeForType(*this, Ty, Min, End, CGM.getCodeGenOpts().StrictEnums,
1344 hasBooleanRepresentation(Ty)))
1347 llvm::MDBuilder MDHelper(getLLVMContext());
1348 return MDHelper.createRange(Min, End);
1351 bool CodeGenFunction::EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
1352 SourceLocation Loc) {
1353 bool HasBoolCheck = SanOpts.has(SanitizerKind::Bool);
1354 bool HasEnumCheck = SanOpts.has(SanitizerKind::Enum);
1355 if (!HasBoolCheck && !HasEnumCheck)
1358 bool IsBool = hasBooleanRepresentation(Ty) ||
1359 NSAPI(CGM.getContext()).isObjCBOOLType(Ty);
1360 bool NeedsBoolCheck = HasBoolCheck && IsBool;
1361 bool NeedsEnumCheck = HasEnumCheck && Ty->getAs<EnumType>();
1362 if (!NeedsBoolCheck && !NeedsEnumCheck)
1365 // Single-bit booleans don't need to be checked. Special-case this to avoid
1366 // a bit width mismatch when handling bitfield values. This is handled by
1367 // EmitFromMemory for the non-bitfield case.
1369 cast<llvm::IntegerType>(Value->getType())->getBitWidth() == 1)
1372 llvm::APInt Min, End;
1373 if (!getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true, IsBool))
1376 SanitizerScope SanScope(this);
1380 Check = Builder.CreateICmpULE(
1381 Value, llvm::ConstantInt::get(getLLVMContext(), End));
1383 llvm::Value *Upper = Builder.CreateICmpSLE(
1384 Value, llvm::ConstantInt::get(getLLVMContext(), End));
1385 llvm::Value *Lower = Builder.CreateICmpSGE(
1386 Value, llvm::ConstantInt::get(getLLVMContext(), Min));
1387 Check = Builder.CreateAnd(Upper, Lower);
1389 llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc),
1390 EmitCheckTypeDescriptor(Ty)};
1391 SanitizerMask Kind =
1392 NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool;
1393 EmitCheck(std::make_pair(Check, Kind), SanitizerHandler::LoadInvalidValue,
1394 StaticArgs, EmitCheckValue(Value));
1398 llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile,
1401 LValueBaseInfo BaseInfo,
1402 llvm::MDNode *TBAAInfo,
1403 QualType TBAABaseType,
1404 uint64_t TBAAOffset,
1405 bool isNontemporal) {
1406 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1407 // For better performance, handle vector loads differently.
1408 if (Ty->isVectorType()) {
1409 const llvm::Type *EltTy = Addr.getElementType();
1411 const auto *VTy = cast<llvm::VectorType>(EltTy);
1413 // Handle vectors of size 3 like size 4 for better performance.
1414 if (VTy->getNumElements() == 3) {
1416 // Bitcast to vec4 type.
1417 llvm::VectorType *vec4Ty =
1418 llvm::VectorType::get(VTy->getElementType(), 4);
1419 Address Cast = Builder.CreateElementBitCast(Addr, vec4Ty, "castToVec4");
1421 llvm::Value *V = Builder.CreateLoad(Cast, Volatile, "loadVec4");
1423 // Shuffle vector to get vec3.
1424 V = Builder.CreateShuffleVector(V, llvm::UndefValue::get(vec4Ty),
1425 {0, 1, 2}, "extractVec");
1426 return EmitFromMemory(V, Ty);
1431 // Atomic operations have to be done on integral types.
1432 LValue AtomicLValue =
1433 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1434 if (Ty->isAtomicType() || LValueIsSuitableForInlineAtomic(AtomicLValue)) {
1435 return EmitAtomicLoad(AtomicLValue, Loc).getScalarVal();
1438 llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile);
1439 if (isNontemporal) {
1440 llvm::MDNode *Node = llvm::MDNode::get(
1441 Load->getContext(), llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1442 Load->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1445 bool MayAlias = BaseInfo.getMayAlias();
1446 llvm::MDNode *TBAA = MayAlias
1447 ? CGM.getTBAAInfo(getContext().CharTy)
1448 : CGM.getTBAAStructTagInfo(TBAABaseType, TBAAInfo, TBAAOffset);
1450 CGM.DecorateInstructionWithTBAA(Load, TBAA, MayAlias);
1453 if (EmitScalarRangeCheck(Load, Ty, Loc)) {
1454 // In order to prevent the optimizer from throwing away the check, don't
1455 // attach range metadata to the load.
1456 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0)
1457 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty))
1458 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo);
1460 return EmitFromMemory(Load, Ty);
1463 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
1464 // Bool has a different representation in memory than in registers.
1465 if (hasBooleanRepresentation(Ty)) {
1466 // This should really always be an i1, but sometimes it's already
1467 // an i8, and it's awkward to track those cases down.
1468 if (Value->getType()->isIntegerTy(1))
1469 return Builder.CreateZExt(Value, ConvertTypeForMem(Ty), "frombool");
1470 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1471 "wrong value rep of bool");
1477 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
1478 // Bool has a different representation in memory than in registers.
1479 if (hasBooleanRepresentation(Ty)) {
1480 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1481 "wrong value rep of bool");
1482 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool");
1488 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr,
1489 bool Volatile, QualType Ty,
1490 LValueBaseInfo BaseInfo,
1491 llvm::MDNode *TBAAInfo,
1492 bool isInit, QualType TBAABaseType,
1493 uint64_t TBAAOffset,
1494 bool isNontemporal) {
1496 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1497 // Handle vectors differently to get better performance.
1498 if (Ty->isVectorType()) {
1499 llvm::Type *SrcTy = Value->getType();
1500 auto *VecTy = dyn_cast<llvm::VectorType>(SrcTy);
1501 // Handle vec3 special.
1502 if (VecTy && VecTy->getNumElements() == 3) {
1503 // Our source is a vec3, do a shuffle vector to make it a vec4.
1504 llvm::Constant *Mask[] = {Builder.getInt32(0), Builder.getInt32(1),
1505 Builder.getInt32(2),
1506 llvm::UndefValue::get(Builder.getInt32Ty())};
1507 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1508 Value = Builder.CreateShuffleVector(Value, llvm::UndefValue::get(VecTy),
1509 MaskV, "extractVec");
1510 SrcTy = llvm::VectorType::get(VecTy->getElementType(), 4);
1512 if (Addr.getElementType() != SrcTy) {
1513 Addr = Builder.CreateElementBitCast(Addr, SrcTy, "storetmp");
1518 Value = EmitToMemory(Value, Ty);
1520 LValue AtomicLValue =
1521 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1522 if (Ty->isAtomicType() ||
1523 (!isInit && LValueIsSuitableForInlineAtomic(AtomicLValue))) {
1524 EmitAtomicStore(RValue::get(Value), AtomicLValue, isInit);
1528 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
1529 if (isNontemporal) {
1530 llvm::MDNode *Node =
1531 llvm::MDNode::get(Store->getContext(),
1532 llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1533 Store->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1536 bool MayAlias = BaseInfo.getMayAlias();
1537 llvm::MDNode *TBAA = MayAlias
1538 ? CGM.getTBAAInfo(getContext().CharTy)
1539 : CGM.getTBAAStructTagInfo(TBAABaseType, TBAAInfo, TBAAOffset);
1541 CGM.DecorateInstructionWithTBAA(Store, TBAA, MayAlias);
1545 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue,
1547 EmitStoreOfScalar(value, lvalue.getAddress(), lvalue.isVolatile(),
1548 lvalue.getType(), lvalue.getBaseInfo(),
1549 lvalue.getTBAAInfo(), isInit, lvalue.getTBAABaseType(),
1550 lvalue.getTBAAOffset(), lvalue.isNontemporal());
1553 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
1554 /// method emits the address of the lvalue, then loads the result as an rvalue,
1555 /// returning the rvalue.
1556 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
1557 if (LV.isObjCWeak()) {
1558 // load of a __weak object.
1559 Address AddrWeakObj = LV.getAddress();
1560 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
1563 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
1564 // In MRC mode, we do a load+autorelease.
1565 if (!getLangOpts().ObjCAutoRefCount) {
1566 return RValue::get(EmitARCLoadWeak(LV.getAddress()));
1569 // In ARC mode, we load retained and then consume the value.
1570 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress());
1571 Object = EmitObjCConsumeObject(LV.getType(), Object);
1572 return RValue::get(Object);
1575 if (LV.isSimple()) {
1576 assert(!LV.getType()->isFunctionType());
1578 // Everything needs a load.
1579 return RValue::get(EmitLoadOfScalar(LV, Loc));
1582 if (LV.isVectorElt()) {
1583 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddress(),
1584 LV.isVolatileQualified());
1585 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(),
1589 // If this is a reference to a subset of the elements of a vector, either
1590 // shuffle the input or extract/insert them as appropriate.
1591 if (LV.isExtVectorElt())
1592 return EmitLoadOfExtVectorElementLValue(LV);
1594 // Global Register variables always invoke intrinsics
1595 if (LV.isGlobalReg())
1596 return EmitLoadOfGlobalRegLValue(LV);
1598 assert(LV.isBitField() && "Unknown LValue type!");
1599 return EmitLoadOfBitfieldLValue(LV, Loc);
1602 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
1603 SourceLocation Loc) {
1604 const CGBitFieldInfo &Info = LV.getBitFieldInfo();
1606 // Get the output type.
1607 llvm::Type *ResLTy = ConvertType(LV.getType());
1609 Address Ptr = LV.getBitFieldAddress();
1610 llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "bf.load");
1612 if (Info.IsSigned) {
1613 assert(static_cast<unsigned>(Info.Offset + Info.Size) <= Info.StorageSize);
1614 unsigned HighBits = Info.StorageSize - Info.Offset - Info.Size;
1616 Val = Builder.CreateShl(Val, HighBits, "bf.shl");
1617 if (Info.Offset + HighBits)
1618 Val = Builder.CreateAShr(Val, Info.Offset + HighBits, "bf.ashr");
1621 Val = Builder.CreateLShr(Val, Info.Offset, "bf.lshr");
1622 if (static_cast<unsigned>(Info.Offset) + Info.Size < Info.StorageSize)
1623 Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(Info.StorageSize,
1627 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast");
1628 EmitScalarRangeCheck(Val, LV.getType(), Loc);
1629 return RValue::get(Val);
1632 // If this is a reference to a subset of the elements of a vector, create an
1633 // appropriate shufflevector.
1634 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) {
1635 llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddress(),
1636 LV.isVolatileQualified());
1638 const llvm::Constant *Elts = LV.getExtVectorElts();
1640 // If the result of the expression is a non-vector type, we must be extracting
1641 // a single element. Just codegen as an extractelement.
1642 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1644 unsigned InIdx = getAccessedFieldNo(0, Elts);
1645 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1646 return RValue::get(Builder.CreateExtractElement(Vec, Elt));
1649 // Always use shuffle vector to try to retain the original program structure
1650 unsigned NumResultElts = ExprVT->getNumElements();
1652 SmallVector<llvm::Constant*, 4> Mask;
1653 for (unsigned i = 0; i != NumResultElts; ++i)
1654 Mask.push_back(Builder.getInt32(getAccessedFieldNo(i, Elts)));
1656 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1657 Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()),
1659 return RValue::get(Vec);
1662 /// @brief Generates lvalue for partial ext_vector access.
1663 Address CodeGenFunction::EmitExtVectorElementLValue(LValue LV) {
1664 Address VectorAddress = LV.getExtVectorAddress();
1665 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1666 QualType EQT = ExprVT->getElementType();
1667 llvm::Type *VectorElementTy = CGM.getTypes().ConvertType(EQT);
1669 Address CastToPointerElement =
1670 Builder.CreateElementBitCast(VectorAddress, VectorElementTy,
1671 "conv.ptr.element");
1673 const llvm::Constant *Elts = LV.getExtVectorElts();
1674 unsigned ix = getAccessedFieldNo(0, Elts);
1676 Address VectorBasePtrPlusIx =
1677 Builder.CreateConstInBoundsGEP(CastToPointerElement, ix,
1678 getContext().getTypeSizeInChars(EQT),
1681 return VectorBasePtrPlusIx;
1684 /// @brief Load of global gamed gegisters are always calls to intrinsics.
1685 RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) {
1686 assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) &&
1687 "Bad type for register variable");
1688 llvm::MDNode *RegName = cast<llvm::MDNode>(
1689 cast<llvm::MetadataAsValue>(LV.getGlobalReg())->getMetadata());
1691 // We accept integer and pointer types only
1692 llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType());
1693 llvm::Type *Ty = OrigTy;
1694 if (OrigTy->isPointerTy())
1695 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
1696 llvm::Type *Types[] = { Ty };
1698 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types);
1699 llvm::Value *Call = Builder.CreateCall(
1700 F, llvm::MetadataAsValue::get(Ty->getContext(), RegName));
1701 if (OrigTy->isPointerTy())
1702 Call = Builder.CreateIntToPtr(Call, OrigTy);
1703 return RValue::get(Call);
1707 /// EmitStoreThroughLValue - Store the specified rvalue into the specified
1708 /// lvalue, where both are guaranteed to the have the same type, and that type
1710 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
1712 if (!Dst.isSimple()) {
1713 if (Dst.isVectorElt()) {
1714 // Read/modify/write the vector, inserting the new element.
1715 llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddress(),
1716 Dst.isVolatileQualified());
1717 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
1718 Dst.getVectorIdx(), "vecins");
1719 Builder.CreateStore(Vec, Dst.getVectorAddress(),
1720 Dst.isVolatileQualified());
1724 // If this is an update of extended vector elements, insert them as
1726 if (Dst.isExtVectorElt())
1727 return EmitStoreThroughExtVectorComponentLValue(Src, Dst);
1729 if (Dst.isGlobalReg())
1730 return EmitStoreThroughGlobalRegLValue(Src, Dst);
1732 assert(Dst.isBitField() && "Unknown LValue type");
1733 return EmitStoreThroughBitfieldLValue(Src, Dst);
1736 // There's special magic for assigning into an ARC-qualified l-value.
1737 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) {
1739 case Qualifiers::OCL_None:
1740 llvm_unreachable("present but none");
1742 case Qualifiers::OCL_ExplicitNone:
1746 case Qualifiers::OCL_Strong:
1748 Src = RValue::get(EmitARCRetain(Dst.getType(), Src.getScalarVal()));
1751 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true);
1754 case Qualifiers::OCL_Weak:
1756 // Initialize and then skip the primitive store.
1757 EmitARCInitWeak(Dst.getAddress(), Src.getScalarVal());
1759 EmitARCStoreWeak(Dst.getAddress(), Src.getScalarVal(), /*ignore*/ true);
1762 case Qualifiers::OCL_Autoreleasing:
1763 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(),
1764 Src.getScalarVal()));
1765 // fall into the normal path
1770 if (Dst.isObjCWeak() && !Dst.isNonGC()) {
1771 // load of a __weak object.
1772 Address LvalueDst = Dst.getAddress();
1773 llvm::Value *src = Src.getScalarVal();
1774 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
1778 if (Dst.isObjCStrong() && !Dst.isNonGC()) {
1779 // load of a __strong object.
1780 Address LvalueDst = Dst.getAddress();
1781 llvm::Value *src = Src.getScalarVal();
1782 if (Dst.isObjCIvar()) {
1783 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
1784 llvm::Type *ResultType = IntPtrTy;
1785 Address dst = EmitPointerWithAlignment(Dst.getBaseIvarExp());
1786 llvm::Value *RHS = dst.getPointer();
1787 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
1789 Builder.CreatePtrToInt(LvalueDst.getPointer(), ResultType,
1790 "sub.ptr.lhs.cast");
1791 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
1792 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
1794 } else if (Dst.isGlobalObjCRef()) {
1795 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
1796 Dst.isThreadLocalRef());
1799 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
1803 assert(Src.isScalar() && "Can't emit an agg store with this method");
1804 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit);
1807 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
1808 llvm::Value **Result) {
1809 const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
1810 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType());
1811 Address Ptr = Dst.getBitFieldAddress();
1813 // Get the source value, truncated to the width of the bit-field.
1814 llvm::Value *SrcVal = Src.getScalarVal();
1816 // Cast the source to the storage type and shift it into place.
1817 SrcVal = Builder.CreateIntCast(SrcVal, Ptr.getElementType(),
1818 /*IsSigned=*/false);
1819 llvm::Value *MaskedVal = SrcVal;
1821 // See if there are other bits in the bitfield's storage we'll need to load
1822 // and mask together with source before storing.
1823 if (Info.StorageSize != Info.Size) {
1824 assert(Info.StorageSize > Info.Size && "Invalid bitfield size.");
1826 Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.load");
1828 // Mask the source value as needed.
1829 if (!hasBooleanRepresentation(Dst.getType()))
1830 SrcVal = Builder.CreateAnd(SrcVal,
1831 llvm::APInt::getLowBitsSet(Info.StorageSize,
1836 SrcVal = Builder.CreateShl(SrcVal, Info.Offset, "bf.shl");
1838 // Mask out the original value.
1839 Val = Builder.CreateAnd(Val,
1840 ~llvm::APInt::getBitsSet(Info.StorageSize,
1842 Info.Offset + Info.Size),
1845 // Or together the unchanged values and the source value.
1846 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set");
1848 assert(Info.Offset == 0);
1851 // Write the new value back out.
1852 Builder.CreateStore(SrcVal, Ptr, Dst.isVolatileQualified());
1854 // Return the new value of the bit-field, if requested.
1856 llvm::Value *ResultVal = MaskedVal;
1858 // Sign extend the value if needed.
1859 if (Info.IsSigned) {
1860 assert(Info.Size <= Info.StorageSize);
1861 unsigned HighBits = Info.StorageSize - Info.Size;
1863 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl");
1864 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr");
1868 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned,
1870 *Result = EmitFromMemory(ResultVal, Dst.getType());
1874 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
1876 // This access turns into a read/modify/write of the vector. Load the input
1878 llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddress(),
1879 Dst.isVolatileQualified());
1880 const llvm::Constant *Elts = Dst.getExtVectorElts();
1882 llvm::Value *SrcVal = Src.getScalarVal();
1884 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) {
1885 unsigned NumSrcElts = VTy->getNumElements();
1886 unsigned NumDstElts = Vec->getType()->getVectorNumElements();
1887 if (NumDstElts == NumSrcElts) {
1888 // Use shuffle vector is the src and destination are the same number of
1889 // elements and restore the vector mask since it is on the side it will be
1891 SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
1892 for (unsigned i = 0; i != NumSrcElts; ++i)
1893 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i);
1895 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1896 Vec = Builder.CreateShuffleVector(SrcVal,
1897 llvm::UndefValue::get(Vec->getType()),
1899 } else if (NumDstElts > NumSrcElts) {
1900 // Extended the source vector to the same length and then shuffle it
1901 // into the destination.
1902 // FIXME: since we're shuffling with undef, can we just use the indices
1903 // into that? This could be simpler.
1904 SmallVector<llvm::Constant*, 4> ExtMask;
1905 for (unsigned i = 0; i != NumSrcElts; ++i)
1906 ExtMask.push_back(Builder.getInt32(i));
1907 ExtMask.resize(NumDstElts, llvm::UndefValue::get(Int32Ty));
1908 llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask);
1909 llvm::Value *ExtSrcVal =
1910 Builder.CreateShuffleVector(SrcVal,
1911 llvm::UndefValue::get(SrcVal->getType()),
1914 SmallVector<llvm::Constant*, 4> Mask;
1915 for (unsigned i = 0; i != NumDstElts; ++i)
1916 Mask.push_back(Builder.getInt32(i));
1918 // When the vector size is odd and .odd or .hi is used, the last element
1919 // of the Elts constant array will be one past the size of the vector.
1920 // Ignore the last element here, if it is greater than the mask size.
1921 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size())
1924 // modify when what gets shuffled in
1925 for (unsigned i = 0; i != NumSrcElts; ++i)
1926 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i+NumDstElts);
1927 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1928 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV);
1930 // We should never shorten the vector
1931 llvm_unreachable("unexpected shorten vector length");
1934 // If the Src is a scalar (not a vector) it must be updating one element.
1935 unsigned InIdx = getAccessedFieldNo(0, Elts);
1936 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1937 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt);
1940 Builder.CreateStore(Vec, Dst.getExtVectorAddress(),
1941 Dst.isVolatileQualified());
1944 /// @brief Store of global named registers are always calls to intrinsics.
1945 void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) {
1946 assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) &&
1947 "Bad type for register variable");
1948 llvm::MDNode *RegName = cast<llvm::MDNode>(
1949 cast<llvm::MetadataAsValue>(Dst.getGlobalReg())->getMetadata());
1950 assert(RegName && "Register LValue is not metadata");
1952 // We accept integer and pointer types only
1953 llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType());
1954 llvm::Type *Ty = OrigTy;
1955 if (OrigTy->isPointerTy())
1956 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
1957 llvm::Type *Types[] = { Ty };
1959 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types);
1960 llvm::Value *Value = Src.getScalarVal();
1961 if (OrigTy->isPointerTy())
1962 Value = Builder.CreatePtrToInt(Value, Ty);
1964 F, {llvm::MetadataAsValue::get(Ty->getContext(), RegName), Value});
1967 // setObjCGCLValueClass - sets class of the lvalue for the purpose of
1968 // generating write-barries API. It is currently a global, ivar,
1970 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
1972 bool IsMemberAccess=false) {
1973 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC)
1976 if (isa<ObjCIvarRefExpr>(E)) {
1977 QualType ExpTy = E->getType();
1978 if (IsMemberAccess && ExpTy->isPointerType()) {
1979 // If ivar is a structure pointer, assigning to field of
1980 // this struct follows gcc's behavior and makes it a non-ivar
1981 // writer-barrier conservatively.
1982 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
1983 if (ExpTy->isRecordType()) {
1984 LV.setObjCIvar(false);
1988 LV.setObjCIvar(true);
1989 auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E));
1990 LV.setBaseIvarExp(Exp->getBase());
1991 LV.setObjCArray(E->getType()->isArrayType());
1995 if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) {
1996 if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
1997 if (VD->hasGlobalStorage()) {
1998 LV.setGlobalObjCRef(true);
1999 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None);
2002 LV.setObjCArray(E->getType()->isArrayType());
2006 if (const auto *Exp = dyn_cast<UnaryOperator>(E)) {
2007 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2011 if (const auto *Exp = dyn_cast<ParenExpr>(E)) {
2012 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2013 if (LV.isObjCIvar()) {
2014 // If cast is to a structure pointer, follow gcc's behavior and make it
2015 // a non-ivar write-barrier.
2016 QualType ExpTy = E->getType();
2017 if (ExpTy->isPointerType())
2018 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
2019 if (ExpTy->isRecordType())
2020 LV.setObjCIvar(false);
2025 if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) {
2026 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV);
2030 if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) {
2031 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2035 if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) {
2036 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2040 if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) {
2041 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2045 if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
2046 setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
2047 if (LV.isObjCIvar() && !LV.isObjCArray())
2048 // Using array syntax to assigning to what an ivar points to is not
2049 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
2050 LV.setObjCIvar(false);
2051 else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
2052 // Using array syntax to assigning to what global points to is not
2053 // same as assigning to the global itself. {id *G;} G[i] = 0;
2054 LV.setGlobalObjCRef(false);
2058 if (const auto *Exp = dyn_cast<MemberExpr>(E)) {
2059 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true);
2060 // We don't know if member is an 'ivar', but this flag is looked at
2061 // only in the context of LV.isObjCIvar().
2062 LV.setObjCArray(E->getType()->isArrayType());
2067 static llvm::Value *
2068 EmitBitCastOfLValueToProperType(CodeGenFunction &CGF,
2069 llvm::Value *V, llvm::Type *IRType,
2070 StringRef Name = StringRef()) {
2071 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace();
2072 return CGF.Builder.CreateBitCast(V, IRType->getPointerTo(AS), Name);
2075 static LValue EmitThreadPrivateVarDeclLValue(
2076 CodeGenFunction &CGF, const VarDecl *VD, QualType T, Address Addr,
2077 llvm::Type *RealVarTy, SourceLocation Loc) {
2078 Addr = CGF.CGM.getOpenMPRuntime().getAddrOfThreadPrivate(CGF, VD, Addr, Loc);
2079 Addr = CGF.Builder.CreateElementBitCast(Addr, RealVarTy);
2080 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2081 return CGF.MakeAddrLValue(Addr, T, BaseInfo);
2084 Address CodeGenFunction::EmitLoadOfReference(Address Addr,
2085 const ReferenceType *RefTy,
2086 LValueBaseInfo *BaseInfo) {
2087 llvm::Value *Ptr = Builder.CreateLoad(Addr);
2088 return Address(Ptr, getNaturalTypeAlignment(RefTy->getPointeeType(),
2089 BaseInfo, /*forPointee*/ true));
2092 LValue CodeGenFunction::EmitLoadOfReferenceLValue(Address RefAddr,
2093 const ReferenceType *RefTy) {
2094 LValueBaseInfo BaseInfo;
2095 Address Addr = EmitLoadOfReference(RefAddr, RefTy, &BaseInfo);
2096 return MakeAddrLValue(Addr, RefTy->getPointeeType(), BaseInfo);
2099 Address CodeGenFunction::EmitLoadOfPointer(Address Ptr,
2100 const PointerType *PtrTy,
2101 LValueBaseInfo *BaseInfo) {
2102 llvm::Value *Addr = Builder.CreateLoad(Ptr);
2103 return Address(Addr, getNaturalTypeAlignment(PtrTy->getPointeeType(),
2105 /*forPointeeType=*/true));
2108 LValue CodeGenFunction::EmitLoadOfPointerLValue(Address PtrAddr,
2109 const PointerType *PtrTy) {
2110 LValueBaseInfo BaseInfo;
2111 Address Addr = EmitLoadOfPointer(PtrAddr, PtrTy, &BaseInfo);
2112 return MakeAddrLValue(Addr, PtrTy->getPointeeType(), BaseInfo);
2115 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
2116 const Expr *E, const VarDecl *VD) {
2117 QualType T = E->getType();
2119 // If it's thread_local, emit a call to its wrapper function instead.
2120 if (VD->getTLSKind() == VarDecl::TLS_Dynamic &&
2121 CGF.CGM.getCXXABI().usesThreadWrapperFunction())
2122 return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T);
2124 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
2125 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType());
2126 V = EmitBitCastOfLValueToProperType(CGF, V, RealVarTy);
2127 CharUnits Alignment = CGF.getContext().getDeclAlign(VD);
2128 Address Addr(V, Alignment);
2130 // Emit reference to the private copy of the variable if it is an OpenMP
2131 // threadprivate variable.
2132 if (CGF.getLangOpts().OpenMP && VD->hasAttr<OMPThreadPrivateDeclAttr>())
2133 return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy,
2135 if (auto RefTy = VD->getType()->getAs<ReferenceType>()) {
2136 LV = CGF.EmitLoadOfReferenceLValue(Addr, RefTy);
2138 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2139 LV = CGF.MakeAddrLValue(Addr, T, BaseInfo);
2141 setObjCGCLValueClass(CGF.getContext(), E, LV);
2145 static llvm::Constant *EmitFunctionDeclPointer(CodeGenModule &CGM,
2146 const FunctionDecl *FD) {
2147 if (FD->hasAttr<WeakRefAttr>()) {
2148 ConstantAddress aliasee = CGM.GetWeakRefReference(FD);
2149 return aliasee.getPointer();
2152 llvm::Constant *V = CGM.GetAddrOfFunction(FD);
2153 if (!FD->hasPrototype()) {
2154 if (const FunctionProtoType *Proto =
2155 FD->getType()->getAs<FunctionProtoType>()) {
2156 // Ugly case: for a K&R-style definition, the type of the definition
2157 // isn't the same as the type of a use. Correct for this with a
2159 QualType NoProtoType =
2160 CGM.getContext().getFunctionNoProtoType(Proto->getReturnType());
2161 NoProtoType = CGM.getContext().getPointerType(NoProtoType);
2162 V = llvm::ConstantExpr::getBitCast(V,
2163 CGM.getTypes().ConvertType(NoProtoType));
2169 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
2170 const Expr *E, const FunctionDecl *FD) {
2171 llvm::Value *V = EmitFunctionDeclPointer(CGF.CGM, FD);
2172 CharUnits Alignment = CGF.getContext().getDeclAlign(FD);
2173 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2174 return CGF.MakeAddrLValue(V, E->getType(), Alignment, BaseInfo);
2177 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD,
2178 llvm::Value *ThisValue) {
2179 QualType TagType = CGF.getContext().getTagDeclType(FD->getParent());
2180 LValue LV = CGF.MakeNaturalAlignAddrLValue(ThisValue, TagType);
2181 return CGF.EmitLValueForField(LV, FD);
2184 /// Named Registers are named metadata pointing to the register name
2185 /// which will be read from/written to as an argument to the intrinsic
2186 /// @llvm.read/write_register.
2187 /// So far, only the name is being passed down, but other options such as
2188 /// register type, allocation type or even optimization options could be
2189 /// passed down via the metadata node.
2190 static LValue EmitGlobalNamedRegister(const VarDecl *VD, CodeGenModule &CGM) {
2191 SmallString<64> Name("llvm.named.register.");
2192 AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>();
2193 assert(Asm->getLabel().size() < 64-Name.size() &&
2194 "Register name too big");
2195 Name.append(Asm->getLabel());
2196 llvm::NamedMDNode *M =
2197 CGM.getModule().getOrInsertNamedMetadata(Name);
2198 if (M->getNumOperands() == 0) {
2199 llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(),
2201 llvm::Metadata *Ops[] = {Str};
2202 M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
2205 CharUnits Alignment = CGM.getContext().getDeclAlign(VD);
2208 llvm::MetadataAsValue::get(CGM.getLLVMContext(), M->getOperand(0));
2209 return LValue::MakeGlobalReg(Address(Ptr, Alignment), VD->getType());
2212 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
2213 const NamedDecl *ND = E->getDecl();
2214 QualType T = E->getType();
2216 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2217 // Global Named registers access via intrinsics only
2218 if (VD->getStorageClass() == SC_Register &&
2219 VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl())
2220 return EmitGlobalNamedRegister(VD, CGM);
2222 // A DeclRefExpr for a reference initialized by a constant expression can
2223 // appear without being odr-used. Directly emit the constant initializer.
2224 const Expr *Init = VD->getAnyInitializer(VD);
2225 if (Init && !isa<ParmVarDecl>(VD) && VD->getType()->isReferenceType() &&
2226 VD->isUsableInConstantExpressions(getContext()) &&
2227 VD->checkInitIsICE() &&
2228 // Do not emit if it is private OpenMP variable.
2229 !(E->refersToEnclosingVariableOrCapture() && CapturedStmtInfo &&
2230 LocalDeclMap.count(VD))) {
2231 llvm::Constant *Val =
2232 CGM.EmitConstantValue(*VD->evaluateValue(), VD->getType(), this);
2233 assert(Val && "failed to emit reference constant expression");
2234 // FIXME: Eventually we will want to emit vector element references.
2236 // Should we be using the alignment of the constant pointer we emitted?
2237 CharUnits Alignment = getNaturalTypeAlignment(E->getType(), nullptr,
2239 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2240 return MakeAddrLValue(Address(Val, Alignment), T, BaseInfo);
2243 // Check for captured variables.
2244 if (E->refersToEnclosingVariableOrCapture()) {
2245 if (auto *FD = LambdaCaptureFields.lookup(VD))
2246 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue);
2247 else if (CapturedStmtInfo) {
2248 auto I = LocalDeclMap.find(VD);
2249 if (I != LocalDeclMap.end()) {
2250 if (auto RefTy = VD->getType()->getAs<ReferenceType>())
2251 return EmitLoadOfReferenceLValue(I->second, RefTy);
2252 return MakeAddrLValue(I->second, T);
2255 EmitCapturedFieldLValue(*this, CapturedStmtInfo->lookup(VD),
2256 CapturedStmtInfo->getContextValue());
2257 bool MayAlias = CapLVal.getBaseInfo().getMayAlias();
2258 return MakeAddrLValue(
2259 Address(CapLVal.getPointer(), getContext().getDeclAlign(VD)),
2260 CapLVal.getType(), LValueBaseInfo(AlignmentSource::Decl, MayAlias));
2263 assert(isa<BlockDecl>(CurCodeDecl));
2264 Address addr = GetAddrOfBlockDecl(VD, VD->hasAttr<BlocksAttr>());
2265 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2266 return MakeAddrLValue(addr, T, BaseInfo);
2270 // FIXME: We should be able to assert this for FunctionDecls as well!
2271 // FIXME: We should be able to assert this for all DeclRefExprs, not just
2272 // those with a valid source location.
2273 assert((ND->isUsed(false) || !isa<VarDecl>(ND) ||
2274 !E->getLocation().isValid()) &&
2275 "Should not use decl without marking it used!");
2277 if (ND->hasAttr<WeakRefAttr>()) {
2278 const auto *VD = cast<ValueDecl>(ND);
2279 ConstantAddress Aliasee = CGM.GetWeakRefReference(VD);
2280 return MakeAddrLValue(Aliasee, T,
2281 LValueBaseInfo(AlignmentSource::Decl, false));
2284 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2285 // Check if this is a global variable.
2286 if (VD->hasLinkage() || VD->isStaticDataMember())
2287 return EmitGlobalVarDeclLValue(*this, E, VD);
2289 Address addr = Address::invalid();
2291 // The variable should generally be present in the local decl map.
2292 auto iter = LocalDeclMap.find(VD);
2293 if (iter != LocalDeclMap.end()) {
2294 addr = iter->second;
2296 // Otherwise, it might be static local we haven't emitted yet for
2297 // some reason; most likely, because it's in an outer function.
2298 } else if (VD->isStaticLocal()) {
2299 addr = Address(CGM.getOrCreateStaticVarDecl(
2300 *VD, CGM.getLLVMLinkageVarDefinition(VD, /*isConstant=*/false)),
2301 getContext().getDeclAlign(VD));
2303 // No other cases for now.
2305 llvm_unreachable("DeclRefExpr for Decl not entered in LocalDeclMap?");
2309 // Check for OpenMP threadprivate variables.
2310 if (getLangOpts().OpenMP && VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2311 return EmitThreadPrivateVarDeclLValue(
2312 *this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()),
2316 // Drill into block byref variables.
2317 bool isBlockByref = VD->hasAttr<BlocksAttr>();
2319 addr = emitBlockByrefAddress(addr, VD);
2322 // Drill into reference types.
2324 if (auto RefTy = VD->getType()->getAs<ReferenceType>()) {
2325 LV = EmitLoadOfReferenceLValue(addr, RefTy);
2327 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2328 LV = MakeAddrLValue(addr, T, BaseInfo);
2331 bool isLocalStorage = VD->hasLocalStorage();
2333 bool NonGCable = isLocalStorage &&
2334 !VD->getType()->isReferenceType() &&
2337 LV.getQuals().removeObjCGCAttr();
2341 bool isImpreciseLifetime =
2342 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>());
2343 if (isImpreciseLifetime)
2344 LV.setARCPreciseLifetime(ARCImpreciseLifetime);
2345 setObjCGCLValueClass(getContext(), E, LV);
2349 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
2350 return EmitFunctionDeclLValue(*this, E, FD);
2352 // FIXME: While we're emitting a binding from an enclosing scope, all other
2353 // DeclRefExprs we see should be implicitly treated as if they also refer to
2354 // an enclosing scope.
2355 if (const auto *BD = dyn_cast<BindingDecl>(ND))
2356 return EmitLValue(BD->getBinding());
2358 llvm_unreachable("Unhandled DeclRefExpr");
2361 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
2362 // __extension__ doesn't affect lvalue-ness.
2363 if (E->getOpcode() == UO_Extension)
2364 return EmitLValue(E->getSubExpr());
2366 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
2367 switch (E->getOpcode()) {
2368 default: llvm_unreachable("Unknown unary operator lvalue!");
2370 QualType T = E->getSubExpr()->getType()->getPointeeType();
2371 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
2373 LValueBaseInfo BaseInfo;
2374 Address Addr = EmitPointerWithAlignment(E->getSubExpr(), &BaseInfo);
2375 LValue LV = MakeAddrLValue(Addr, T, BaseInfo);
2376 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
2378 // We should not generate __weak write barrier on indirect reference
2379 // of a pointer to object; as in void foo (__weak id *param); *param = 0;
2380 // But, we continue to generate __strong write barrier on indirect write
2381 // into a pointer to object.
2382 if (getLangOpts().ObjC1 &&
2383 getLangOpts().getGC() != LangOptions::NonGC &&
2385 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
2390 LValue LV = EmitLValue(E->getSubExpr());
2391 assert(LV.isSimple() && "real/imag on non-ordinary l-value");
2393 // __real is valid on scalars. This is a faster way of testing that.
2394 // __imag can only produce an rvalue on scalars.
2395 if (E->getOpcode() == UO_Real &&
2396 !LV.getAddress().getElementType()->isStructTy()) {
2397 assert(E->getSubExpr()->getType()->isArithmeticType());
2401 QualType T = ExprTy->castAs<ComplexType>()->getElementType();
2404 (E->getOpcode() == UO_Real
2405 ? emitAddrOfRealComponent(LV.getAddress(), LV.getType())
2406 : emitAddrOfImagComponent(LV.getAddress(), LV.getType()));
2407 LValue ElemLV = MakeAddrLValue(Component, T, LV.getBaseInfo());
2408 ElemLV.getQuals().addQualifiers(LV.getQuals());
2413 LValue LV = EmitLValue(E->getSubExpr());
2414 bool isInc = E->getOpcode() == UO_PreInc;
2416 if (E->getType()->isAnyComplexType())
2417 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
2419 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
2425 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
2426 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
2428 LValueBaseInfo(AlignmentSource::Decl, false));
2431 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
2432 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
2434 LValueBaseInfo(AlignmentSource::Decl, false));
2437 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
2438 auto SL = E->getFunctionName();
2439 assert(SL != nullptr && "No StringLiteral name in PredefinedExpr");
2440 StringRef FnName = CurFn->getName();
2441 if (FnName.startswith("\01"))
2442 FnName = FnName.substr(1);
2443 StringRef NameItems[] = {
2444 PredefinedExpr::getIdentTypeName(E->getIdentType()), FnName};
2445 std::string GVName = llvm::join(NameItems, NameItems + 2, ".");
2446 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2447 if (auto *BD = dyn_cast<BlockDecl>(CurCodeDecl)) {
2448 std::string Name = SL->getString();
2449 if (!Name.empty()) {
2450 unsigned Discriminator =
2451 CGM.getCXXABI().getMangleContext().getBlockId(BD, true);
2453 Name += "_" + Twine(Discriminator + 1).str();
2454 auto C = CGM.GetAddrOfConstantCString(Name, GVName.c_str());
2455 return MakeAddrLValue(C, E->getType(), BaseInfo);
2457 auto C = CGM.GetAddrOfConstantCString(FnName, GVName.c_str());
2458 return MakeAddrLValue(C, E->getType(), BaseInfo);
2461 auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName);
2462 return MakeAddrLValue(C, E->getType(), BaseInfo);
2465 /// Emit a type description suitable for use by a runtime sanitizer library. The
2466 /// format of a type descriptor is
2469 /// { i16 TypeKind, i16 TypeInfo }
2472 /// followed by an array of i8 containing the type name. TypeKind is 0 for an
2473 /// integer, 1 for a floating point value, and -1 for anything else.
2474 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) {
2475 // Only emit each type's descriptor once.
2476 if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T))
2479 uint16_t TypeKind = -1;
2480 uint16_t TypeInfo = 0;
2482 if (T->isIntegerType()) {
2484 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) |
2485 (T->isSignedIntegerType() ? 1 : 0);
2486 } else if (T->isFloatingType()) {
2488 TypeInfo = getContext().getTypeSize(T);
2491 // Format the type name as if for a diagnostic, including quotes and
2492 // optionally an 'aka'.
2493 SmallString<32> Buffer;
2494 CGM.getDiags().ConvertArgToString(DiagnosticsEngine::ak_qualtype,
2495 (intptr_t)T.getAsOpaquePtr(),
2496 StringRef(), StringRef(), None, Buffer,
2499 llvm::Constant *Components[] = {
2500 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo),
2501 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer)
2503 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components);
2505 auto *GV = new llvm::GlobalVariable(
2506 CGM.getModule(), Descriptor->getType(),
2507 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor);
2508 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2509 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(GV);
2511 // Remember the descriptor for this type.
2512 CGM.setTypeDescriptorInMap(T, GV);
2517 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) {
2518 llvm::Type *TargetTy = IntPtrTy;
2520 // Floating-point types which fit into intptr_t are bitcast to integers
2521 // and then passed directly (after zero-extension, if necessary).
2522 if (V->getType()->isFloatingPointTy()) {
2523 unsigned Bits = V->getType()->getPrimitiveSizeInBits();
2524 if (Bits <= TargetTy->getIntegerBitWidth())
2525 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(),
2529 // Integers which fit in intptr_t are zero-extended and passed directly.
2530 if (V->getType()->isIntegerTy() &&
2531 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth())
2532 return Builder.CreateZExt(V, TargetTy);
2534 // Pointers are passed directly, everything else is passed by address.
2535 if (!V->getType()->isPointerTy()) {
2536 Address Ptr = CreateDefaultAlignTempAlloca(V->getType());
2537 Builder.CreateStore(V, Ptr);
2538 V = Ptr.getPointer();
2540 return Builder.CreatePtrToInt(V, TargetTy);
2543 /// \brief Emit a representation of a SourceLocation for passing to a handler
2544 /// in a sanitizer runtime library. The format for this data is:
2546 /// struct SourceLocation {
2547 /// const char *Filename;
2548 /// int32_t Line, Column;
2551 /// For an invalid SourceLocation, the Filename pointer is null.
2552 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
2553 llvm::Constant *Filename;
2556 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc);
2557 if (PLoc.isValid()) {
2558 StringRef FilenameString = PLoc.getFilename();
2560 int PathComponentsToStrip =
2561 CGM.getCodeGenOpts().EmitCheckPathComponentsToStrip;
2562 if (PathComponentsToStrip < 0) {
2563 assert(PathComponentsToStrip != INT_MIN);
2564 int PathComponentsToKeep = -PathComponentsToStrip;
2565 auto I = llvm::sys::path::rbegin(FilenameString);
2566 auto E = llvm::sys::path::rend(FilenameString);
2567 while (I != E && --PathComponentsToKeep)
2570 FilenameString = FilenameString.substr(I - E);
2571 } else if (PathComponentsToStrip > 0) {
2572 auto I = llvm::sys::path::begin(FilenameString);
2573 auto E = llvm::sys::path::end(FilenameString);
2574 while (I != E && PathComponentsToStrip--)
2579 FilenameString.substr(I - llvm::sys::path::begin(FilenameString));
2581 FilenameString = llvm::sys::path::filename(FilenameString);
2584 auto FilenameGV = CGM.GetAddrOfConstantCString(FilenameString, ".src");
2585 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(
2586 cast<llvm::GlobalVariable>(FilenameGV.getPointer()));
2587 Filename = FilenameGV.getPointer();
2588 Line = PLoc.getLine();
2589 Column = PLoc.getColumn();
2591 Filename = llvm::Constant::getNullValue(Int8PtrTy);
2595 llvm::Constant *Data[] = {Filename, Builder.getInt32(Line),
2596 Builder.getInt32(Column)};
2598 return llvm::ConstantStruct::getAnon(Data);
2602 /// \brief Specify under what conditions this check can be recovered
2603 enum class CheckRecoverableKind {
2604 /// Always terminate program execution if this check fails.
2606 /// Check supports recovering, runtime has both fatal (noreturn) and
2607 /// non-fatal handlers for this check.
2609 /// Runtime conditionally aborts, always need to support recovery.
2614 static CheckRecoverableKind getRecoverableKind(SanitizerMask Kind) {
2615 assert(llvm::countPopulation(Kind) == 1);
2617 case SanitizerKind::Vptr:
2618 return CheckRecoverableKind::AlwaysRecoverable;
2619 case SanitizerKind::Return:
2620 case SanitizerKind::Unreachable:
2621 return CheckRecoverableKind::Unrecoverable;
2623 return CheckRecoverableKind::Recoverable;
2628 struct SanitizerHandlerInfo {
2629 char const *const Name;
2634 const SanitizerHandlerInfo SanitizerHandlers[] = {
2635 #define SANITIZER_CHECK(Enum, Name, Version) {#Name, Version},
2636 LIST_SANITIZER_CHECKS
2637 #undef SANITIZER_CHECK
2640 static void emitCheckHandlerCall(CodeGenFunction &CGF,
2641 llvm::FunctionType *FnType,
2642 ArrayRef<llvm::Value *> FnArgs,
2643 SanitizerHandler CheckHandler,
2644 CheckRecoverableKind RecoverKind, bool IsFatal,
2645 llvm::BasicBlock *ContBB) {
2646 assert(IsFatal || RecoverKind != CheckRecoverableKind::Unrecoverable);
2647 bool NeedsAbortSuffix =
2648 IsFatal && RecoverKind != CheckRecoverableKind::Unrecoverable;
2649 const SanitizerHandlerInfo &CheckInfo = SanitizerHandlers[CheckHandler];
2650 const StringRef CheckName = CheckInfo.Name;
2651 std::string FnName =
2652 ("__ubsan_handle_" + CheckName +
2653 (CheckInfo.Version ? "_v" + llvm::utostr(CheckInfo.Version) : "") +
2654 (NeedsAbortSuffix ? "_abort" : ""))
2657 !IsFatal || RecoverKind == CheckRecoverableKind::AlwaysRecoverable;
2659 llvm::AttrBuilder B;
2661 B.addAttribute(llvm::Attribute::NoReturn)
2662 .addAttribute(llvm::Attribute::NoUnwind);
2664 B.addAttribute(llvm::Attribute::UWTable);
2666 llvm::Value *Fn = CGF.CGM.CreateRuntimeFunction(
2668 llvm::AttributeList::get(CGF.getLLVMContext(),
2669 llvm::AttributeList::FunctionIndex, B),
2671 llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs);
2673 HandlerCall->setDoesNotReturn();
2674 CGF.Builder.CreateUnreachable();
2676 CGF.Builder.CreateBr(ContBB);
2680 void CodeGenFunction::EmitCheck(
2681 ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
2682 SanitizerHandler CheckHandler, ArrayRef<llvm::Constant *> StaticArgs,
2683 ArrayRef<llvm::Value *> DynamicArgs) {
2684 assert(IsSanitizerScope);
2685 assert(Checked.size() > 0);
2686 assert(CheckHandler >= 0 &&
2687 CheckHandler < sizeof(SanitizerHandlers) / sizeof(*SanitizerHandlers));
2688 const StringRef CheckName = SanitizerHandlers[CheckHandler].Name;
2690 llvm::Value *FatalCond = nullptr;
2691 llvm::Value *RecoverableCond = nullptr;
2692 llvm::Value *TrapCond = nullptr;
2693 for (int i = 0, n = Checked.size(); i < n; ++i) {
2694 llvm::Value *Check = Checked[i].first;
2695 // -fsanitize-trap= overrides -fsanitize-recover=.
2696 llvm::Value *&Cond =
2697 CGM.getCodeGenOpts().SanitizeTrap.has(Checked[i].second)
2699 : CGM.getCodeGenOpts().SanitizeRecover.has(Checked[i].second)
2702 Cond = Cond ? Builder.CreateAnd(Cond, Check) : Check;
2706 EmitTrapCheck(TrapCond);
2707 if (!FatalCond && !RecoverableCond)
2710 llvm::Value *JointCond;
2711 if (FatalCond && RecoverableCond)
2712 JointCond = Builder.CreateAnd(FatalCond, RecoverableCond);
2714 JointCond = FatalCond ? FatalCond : RecoverableCond;
2717 CheckRecoverableKind RecoverKind = getRecoverableKind(Checked[0].second);
2718 assert(SanOpts.has(Checked[0].second));
2720 for (int i = 1, n = Checked.size(); i < n; ++i) {
2721 assert(RecoverKind == getRecoverableKind(Checked[i].second) &&
2722 "All recoverable kinds in a single check must be same!");
2723 assert(SanOpts.has(Checked[i].second));
2727 llvm::BasicBlock *Cont = createBasicBlock("cont");
2728 llvm::BasicBlock *Handlers = createBasicBlock("handler." + CheckName);
2729 llvm::Instruction *Branch = Builder.CreateCondBr(JointCond, Cont, Handlers);
2730 // Give hint that we very much don't expect to execute the handler
2731 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
2732 llvm::MDBuilder MDHelper(getLLVMContext());
2733 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
2734 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node);
2735 EmitBlock(Handlers);
2737 // Handler functions take an i8* pointing to the (handler-specific) static
2738 // information block, followed by a sequence of intptr_t arguments
2739 // representing operand values.
2740 SmallVector<llvm::Value *, 4> Args;
2741 SmallVector<llvm::Type *, 4> ArgTypes;
2742 Args.reserve(DynamicArgs.size() + 1);
2743 ArgTypes.reserve(DynamicArgs.size() + 1);
2745 // Emit handler arguments and create handler function type.
2746 if (!StaticArgs.empty()) {
2747 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
2749 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
2750 llvm::GlobalVariable::PrivateLinkage, Info);
2751 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2752 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
2753 Args.push_back(Builder.CreateBitCast(InfoPtr, Int8PtrTy));
2754 ArgTypes.push_back(Int8PtrTy);
2757 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) {
2758 Args.push_back(EmitCheckValue(DynamicArgs[i]));
2759 ArgTypes.push_back(IntPtrTy);
2762 llvm::FunctionType *FnType =
2763 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false);
2765 if (!FatalCond || !RecoverableCond) {
2766 // Simple case: we need to generate a single handler call, either
2767 // fatal, or non-fatal.
2768 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind,
2769 (FatalCond != nullptr), Cont);
2771 // Emit two handler calls: first one for set of unrecoverable checks,
2772 // another one for recoverable.
2773 llvm::BasicBlock *NonFatalHandlerBB =
2774 createBasicBlock("non_fatal." + CheckName);
2775 llvm::BasicBlock *FatalHandlerBB = createBasicBlock("fatal." + CheckName);
2776 Builder.CreateCondBr(FatalCond, NonFatalHandlerBB, FatalHandlerBB);
2777 EmitBlock(FatalHandlerBB);
2778 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, true,
2780 EmitBlock(NonFatalHandlerBB);
2781 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, false,
2788 void CodeGenFunction::EmitCfiSlowPathCheck(
2789 SanitizerMask Kind, llvm::Value *Cond, llvm::ConstantInt *TypeId,
2790 llvm::Value *Ptr, ArrayRef<llvm::Constant *> StaticArgs) {
2791 llvm::BasicBlock *Cont = createBasicBlock("cfi.cont");
2793 llvm::BasicBlock *CheckBB = createBasicBlock("cfi.slowpath");
2794 llvm::BranchInst *BI = Builder.CreateCondBr(Cond, Cont, CheckBB);
2796 llvm::MDBuilder MDHelper(getLLVMContext());
2797 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
2798 BI->setMetadata(llvm::LLVMContext::MD_prof, Node);
2802 bool WithDiag = !CGM.getCodeGenOpts().SanitizeTrap.has(Kind);
2804 llvm::CallInst *CheckCall;
2806 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
2808 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
2809 llvm::GlobalVariable::PrivateLinkage, Info);
2810 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2811 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
2813 llvm::Constant *SlowPathDiagFn = CGM.getModule().getOrInsertFunction(
2814 "__cfi_slowpath_diag",
2815 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy},
2817 CheckCall = Builder.CreateCall(
2819 {TypeId, Ptr, Builder.CreateBitCast(InfoPtr, Int8PtrTy)});
2821 llvm::Constant *SlowPathFn = CGM.getModule().getOrInsertFunction(
2823 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy}, false));
2824 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr});
2827 CheckCall->setDoesNotThrow();
2832 // Emit a stub for __cfi_check function so that the linker knows about this
2833 // symbol in LTO mode.
2834 void CodeGenFunction::EmitCfiCheckStub() {
2835 llvm::Module *M = &CGM.getModule();
2836 auto &Ctx = M->getContext();
2837 llvm::Function *F = llvm::Function::Create(
2838 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, false),
2839 llvm::GlobalValue::WeakAnyLinkage, "__cfi_check", M);
2840 llvm::BasicBlock *BB = llvm::BasicBlock::Create(Ctx, "entry", F);
2841 // FIXME: consider emitting an intrinsic call like
2842 // call void @llvm.cfi_check(i64 %0, i8* %1, i8* %2)
2843 // which can be lowered in CrossDSOCFI pass to the actual contents of
2844 // __cfi_check. This would allow inlining of __cfi_check calls.
2845 llvm::CallInst::Create(
2846 llvm::Intrinsic::getDeclaration(M, llvm::Intrinsic::trap), "", BB);
2847 llvm::ReturnInst::Create(Ctx, nullptr, BB);
2850 // This function is basically a switch over the CFI failure kind, which is
2851 // extracted from CFICheckFailData (1st function argument). Each case is either
2852 // llvm.trap or a call to one of the two runtime handlers, based on
2853 // -fsanitize-trap and -fsanitize-recover settings. Default case (invalid
2854 // failure kind) traps, but this should really never happen. CFICheckFailData
2855 // can be nullptr if the calling module has -fsanitize-trap behavior for this
2856 // check kind; in this case __cfi_check_fail traps as well.
2857 void CodeGenFunction::EmitCfiCheckFail() {
2858 SanitizerScope SanScope(this);
2859 FunctionArgList Args;
2860 ImplicitParamDecl ArgData(getContext(), getContext().VoidPtrTy,
2861 ImplicitParamDecl::Other);
2862 ImplicitParamDecl ArgAddr(getContext(), getContext().VoidPtrTy,
2863 ImplicitParamDecl::Other);
2864 Args.push_back(&ArgData);
2865 Args.push_back(&ArgAddr);
2867 const CGFunctionInfo &FI =
2868 CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, Args);
2870 llvm::Function *F = llvm::Function::Create(
2871 llvm::FunctionType::get(VoidTy, {VoidPtrTy, VoidPtrTy}, false),
2872 llvm::GlobalValue::WeakODRLinkage, "__cfi_check_fail", &CGM.getModule());
2873 F->setVisibility(llvm::GlobalValue::HiddenVisibility);
2875 StartFunction(GlobalDecl(), CGM.getContext().VoidTy, F, FI, Args,
2879 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgData), /*Volatile=*/false,
2880 CGM.getContext().VoidPtrTy, ArgData.getLocation());
2882 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgAddr), /*Volatile=*/false,
2883 CGM.getContext().VoidPtrTy, ArgAddr.getLocation());
2885 // Data == nullptr means the calling module has trap behaviour for this check.
2886 llvm::Value *DataIsNotNullPtr =
2887 Builder.CreateICmpNE(Data, llvm::ConstantPointerNull::get(Int8PtrTy));
2888 EmitTrapCheck(DataIsNotNullPtr);
2890 llvm::StructType *SourceLocationTy =
2891 llvm::StructType::get(VoidPtrTy, Int32Ty, Int32Ty);
2892 llvm::StructType *CfiCheckFailDataTy =
2893 llvm::StructType::get(Int8Ty, SourceLocationTy, VoidPtrTy);
2895 llvm::Value *V = Builder.CreateConstGEP2_32(
2897 Builder.CreatePointerCast(Data, CfiCheckFailDataTy->getPointerTo(0)), 0,
2899 Address CheckKindAddr(V, getIntAlign());
2900 llvm::Value *CheckKind = Builder.CreateLoad(CheckKindAddr);
2902 llvm::Value *AllVtables = llvm::MetadataAsValue::get(
2903 CGM.getLLVMContext(),
2904 llvm::MDString::get(CGM.getLLVMContext(), "all-vtables"));
2905 llvm::Value *ValidVtable = Builder.CreateZExt(
2906 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::type_test),
2907 {Addr, AllVtables}),
2910 const std::pair<int, SanitizerMask> CheckKinds[] = {
2911 {CFITCK_VCall, SanitizerKind::CFIVCall},
2912 {CFITCK_NVCall, SanitizerKind::CFINVCall},
2913 {CFITCK_DerivedCast, SanitizerKind::CFIDerivedCast},
2914 {CFITCK_UnrelatedCast, SanitizerKind::CFIUnrelatedCast},
2915 {CFITCK_ICall, SanitizerKind::CFIICall}};
2917 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 5> Checks;
2918 for (auto CheckKindMaskPair : CheckKinds) {
2919 int Kind = CheckKindMaskPair.first;
2920 SanitizerMask Mask = CheckKindMaskPair.second;
2922 Builder.CreateICmpNE(CheckKind, llvm::ConstantInt::get(Int8Ty, Kind));
2923 if (CGM.getLangOpts().Sanitize.has(Mask))
2924 EmitCheck(std::make_pair(Cond, Mask), SanitizerHandler::CFICheckFail, {},
2925 {Data, Addr, ValidVtable});
2927 EmitTrapCheck(Cond);
2931 // The only reference to this function will be created during LTO link.
2932 // Make sure it survives until then.
2933 CGM.addUsedGlobal(F);
2936 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked) {
2937 llvm::BasicBlock *Cont = createBasicBlock("cont");
2939 // If we're optimizing, collapse all calls to trap down to just one per
2940 // function to save on code size.
2941 if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB) {
2942 TrapBB = createBasicBlock("trap");
2943 Builder.CreateCondBr(Checked, Cont, TrapBB);
2945 llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
2946 TrapCall->setDoesNotReturn();
2947 TrapCall->setDoesNotThrow();
2948 Builder.CreateUnreachable();
2950 Builder.CreateCondBr(Checked, Cont, TrapBB);
2956 llvm::CallInst *CodeGenFunction::EmitTrapCall(llvm::Intrinsic::ID IntrID) {
2957 llvm::CallInst *TrapCall = Builder.CreateCall(CGM.getIntrinsic(IntrID));
2959 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) {
2960 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name",
2961 CGM.getCodeGenOpts().TrapFuncName);
2962 TrapCall->addAttribute(llvm::AttributeList::FunctionIndex, A);
2968 Address CodeGenFunction::EmitArrayToPointerDecay(const Expr *E,
2969 LValueBaseInfo *BaseInfo) {
2970 assert(E->getType()->isArrayType() &&
2971 "Array to pointer decay must have array source type!");
2973 // Expressions of array type can't be bitfields or vector elements.
2974 LValue LV = EmitLValue(E);
2975 Address Addr = LV.getAddress();
2976 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
2978 // If the array type was an incomplete type, we need to make sure
2979 // the decay ends up being the right type.
2980 llvm::Type *NewTy = ConvertType(E->getType());
2981 Addr = Builder.CreateElementBitCast(Addr, NewTy);
2983 // Note that VLA pointers are always decayed, so we don't need to do
2985 if (!E->getType()->isVariableArrayType()) {
2986 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
2987 "Expected pointer to array");
2988 Addr = Builder.CreateStructGEP(Addr, 0, CharUnits::Zero(), "arraydecay");
2991 QualType EltType = E->getType()->castAsArrayTypeUnsafe()->getElementType();
2992 return Builder.CreateElementBitCast(Addr, ConvertTypeForMem(EltType));
2995 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
2996 /// array to pointer, return the array subexpression.
2997 static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
2998 // If this isn't just an array->pointer decay, bail out.
2999 const auto *CE = dyn_cast<CastExpr>(E);
3000 if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay)
3003 // If this is a decay from variable width array, bail out.
3004 const Expr *SubExpr = CE->getSubExpr();
3005 if (SubExpr->getType()->isVariableArrayType())
3011 static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF,
3013 ArrayRef<llvm::Value*> indices,
3017 const llvm::Twine &name = "arrayidx") {
3019 return CGF.EmitCheckedInBoundsGEP(ptr, indices, signedIndices, loc, name);
3021 return CGF.Builder.CreateGEP(ptr, indices, name);
3025 static CharUnits getArrayElementAlign(CharUnits arrayAlign,
3027 CharUnits eltSize) {
3028 // If we have a constant index, we can use the exact offset of the
3029 // element we're accessing.
3030 if (auto constantIdx = dyn_cast<llvm::ConstantInt>(idx)) {
3031 CharUnits offset = constantIdx->getZExtValue() * eltSize;
3032 return arrayAlign.alignmentAtOffset(offset);
3034 // Otherwise, use the worst-case alignment for any element.
3036 return arrayAlign.alignmentOfArrayElement(eltSize);
3040 static QualType getFixedSizeElementType(const ASTContext &ctx,
3041 const VariableArrayType *vla) {
3044 eltType = vla->getElementType();
3045 } while ((vla = ctx.getAsVariableArrayType(eltType)));
3049 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr,
3050 ArrayRef<llvm::Value *> indices,
3051 QualType eltType, bool inbounds,
3052 bool signedIndices, SourceLocation loc,
3053 const llvm::Twine &name = "arrayidx") {
3054 // All the indices except that last must be zero.
3056 for (auto idx : indices.drop_back())
3057 assert(isa<llvm::ConstantInt>(idx) &&
3058 cast<llvm::ConstantInt>(idx)->isZero());
3061 // Determine the element size of the statically-sized base. This is
3062 // the thing that the indices are expressed in terms of.
3063 if (auto vla = CGF.getContext().getAsVariableArrayType(eltType)) {
3064 eltType = getFixedSizeElementType(CGF.getContext(), vla);
3067 // We can use that to compute the best alignment of the element.
3068 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType);
3069 CharUnits eltAlign =
3070 getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize);
3072 llvm::Value *eltPtr = emitArraySubscriptGEP(
3073 CGF, addr.getPointer(), indices, inbounds, signedIndices, loc, name);
3074 return Address(eltPtr, eltAlign);
3077 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
3079 // The index must always be an integer, which is not an aggregate. Emit it
3080 // in lexical order (this complexity is, sadly, required by C++17).
3081 llvm::Value *IdxPre =
3082 (E->getLHS() == E->getIdx()) ? EmitScalarExpr(E->getIdx()) : nullptr;
3083 bool SignedIndices = false;
3084 auto EmitIdxAfterBase = [&, IdxPre](bool Promote) -> llvm::Value * {
3086 if (E->getLHS() != E->getIdx()) {
3087 assert(E->getRHS() == E->getIdx() && "index was neither LHS nor RHS");
3088 Idx = EmitScalarExpr(E->getIdx());
3091 QualType IdxTy = E->getIdx()->getType();
3092 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType();
3093 SignedIndices |= IdxSigned;
3095 if (SanOpts.has(SanitizerKind::ArrayBounds))
3096 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed);
3098 // Extend or truncate the index type to 32 or 64-bits.
3099 if (Promote && Idx->getType() != IntPtrTy)
3100 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
3106 // If the base is a vector type, then we are forming a vector element lvalue
3107 // with this subscript.
3108 if (E->getBase()->getType()->isVectorType() &&
3109 !isa<ExtVectorElementExpr>(E->getBase())) {
3110 // Emit the vector as an lvalue to get its address.
3111 LValue LHS = EmitLValue(E->getBase());
3112 auto *Idx = EmitIdxAfterBase(/*Promote*/false);
3113 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
3114 return LValue::MakeVectorElt(LHS.getAddress(), Idx,
3115 E->getBase()->getType(),
3119 // All the other cases basically behave like simple offsetting.
3121 // Handle the extvector case we ignored above.
3122 if (isa<ExtVectorElementExpr>(E->getBase())) {
3123 LValue LV = EmitLValue(E->getBase());
3124 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3125 Address Addr = EmitExtVectorElementLValue(LV);
3127 QualType EltType = LV.getType()->castAs<VectorType>()->getElementType();
3128 Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true,
3129 SignedIndices, E->getExprLoc());
3130 return MakeAddrLValue(Addr, EltType, LV.getBaseInfo());
3133 LValueBaseInfo BaseInfo;
3134 Address Addr = Address::invalid();
3135 if (const VariableArrayType *vla =
3136 getContext().getAsVariableArrayType(E->getType())) {
3137 // The base must be a pointer, which is not an aggregate. Emit
3138 // it. It needs to be emitted first in case it's what captures
3140 Addr = EmitPointerWithAlignment(E->getBase(), &BaseInfo);
3141 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3143 // The element count here is the total number of non-VLA elements.
3144 llvm::Value *numElements = getVLASize(vla).first;
3146 // Effectively, the multiply by the VLA size is part of the GEP.
3147 // GEP indexes are signed, and scaling an index isn't permitted to
3148 // signed-overflow, so we use the same semantics for our explicit
3149 // multiply. We suppress this if overflow is not undefined behavior.
3150 if (getLangOpts().isSignedOverflowDefined()) {
3151 Idx = Builder.CreateMul(Idx, numElements);
3153 Idx = Builder.CreateNSWMul(Idx, numElements);
3156 Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(),
3157 !getLangOpts().isSignedOverflowDefined(),
3158 SignedIndices, E->getExprLoc());
3160 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
3161 // Indexing over an interface, as in "NSString *P; P[4];"
3163 // Emit the base pointer.
3164 Addr = EmitPointerWithAlignment(E->getBase(), &BaseInfo);
3165 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3167 CharUnits InterfaceSize = getContext().getTypeSizeInChars(OIT);
3168 llvm::Value *InterfaceSizeVal =
3169 llvm::ConstantInt::get(Idx->getType(), InterfaceSize.getQuantity());
3171 llvm::Value *ScaledIdx = Builder.CreateMul(Idx, InterfaceSizeVal);
3173 // We don't necessarily build correct LLVM struct types for ObjC
3174 // interfaces, so we can't rely on GEP to do this scaling
3175 // correctly, so we need to cast to i8*. FIXME: is this actually
3176 // true? A lot of other things in the fragile ABI would break...
3177 llvm::Type *OrigBaseTy = Addr.getType();
3178 Addr = Builder.CreateElementBitCast(Addr, Int8Ty);
3181 CharUnits EltAlign =
3182 getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize);
3183 llvm::Value *EltPtr =
3184 emitArraySubscriptGEP(*this, Addr.getPointer(), ScaledIdx, false,
3185 SignedIndices, E->getExprLoc());
3186 Addr = Address(EltPtr, EltAlign);
3189 Addr = Builder.CreateBitCast(Addr, OrigBaseTy);
3190 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3191 // If this is A[i] where A is an array, the frontend will have decayed the
3192 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3193 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3194 // "gep x, i" here. Emit one "gep A, 0, i".
3195 assert(Array->getType()->isArrayType() &&
3196 "Array to pointer decay must have array source type!");
3198 // For simple multidimensional array indexing, set the 'accessed' flag for
3199 // better bounds-checking of the base expression.
3200 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3201 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3203 ArrayLV = EmitLValue(Array);
3204 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3206 // Propagate the alignment from the array itself to the result.
3207 Addr = emitArraySubscriptGEP(
3208 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
3209 E->getType(), !getLangOpts().isSignedOverflowDefined(), SignedIndices,
3211 BaseInfo = ArrayLV.getBaseInfo();
3213 // The base must be a pointer; emit it with an estimate of its alignment.
3214 Addr = EmitPointerWithAlignment(E->getBase(), &BaseInfo);
3215 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3216 Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(),
3217 !getLangOpts().isSignedOverflowDefined(),
3218 SignedIndices, E->getExprLoc());
3221 LValue LV = MakeAddrLValue(Addr, E->getType(), BaseInfo);
3223 // TODO: Preserve/extend path TBAA metadata?
3225 if (getLangOpts().ObjC1 &&
3226 getLangOpts().getGC() != LangOptions::NonGC) {
3227 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
3228 setObjCGCLValueClass(getContext(), E, LV);
3233 static Address emitOMPArraySectionBase(CodeGenFunction &CGF, const Expr *Base,
3234 LValueBaseInfo &BaseInfo,
3235 QualType BaseTy, QualType ElTy,
3236 bool IsLowerBound) {
3238 if (auto *ASE = dyn_cast<OMPArraySectionExpr>(Base->IgnoreParenImpCasts())) {
3239 BaseLVal = CGF.EmitOMPArraySectionExpr(ASE, IsLowerBound);
3240 if (BaseTy->isArrayType()) {
3241 Address Addr = BaseLVal.getAddress();
3242 BaseInfo = BaseLVal.getBaseInfo();
3244 // If the array type was an incomplete type, we need to make sure
3245 // the decay ends up being the right type.
3246 llvm::Type *NewTy = CGF.ConvertType(BaseTy);
3247 Addr = CGF.Builder.CreateElementBitCast(Addr, NewTy);
3249 // Note that VLA pointers are always decayed, so we don't need to do
3251 if (!BaseTy->isVariableArrayType()) {
3252 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3253 "Expected pointer to array");
3254 Addr = CGF.Builder.CreateStructGEP(Addr, 0, CharUnits::Zero(),
3258 return CGF.Builder.CreateElementBitCast(Addr,
3259 CGF.ConvertTypeForMem(ElTy));
3261 LValueBaseInfo TypeInfo;
3262 CharUnits Align = CGF.getNaturalTypeAlignment(ElTy, &TypeInfo);
3263 BaseInfo.mergeForCast(TypeInfo);
3264 return Address(CGF.Builder.CreateLoad(BaseLVal.getAddress()), Align);
3266 return CGF.EmitPointerWithAlignment(Base, &BaseInfo);
3269 LValue CodeGenFunction::EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
3270 bool IsLowerBound) {
3273 dyn_cast<OMPArraySectionExpr>(E->getBase()->IgnoreParenImpCasts()))
3274 BaseTy = OMPArraySectionExpr::getBaseOriginalType(ASE);
3276 BaseTy = E->getBase()->getType();
3277 QualType ResultExprTy;
3278 if (auto *AT = getContext().getAsArrayType(BaseTy))
3279 ResultExprTy = AT->getElementType();
3281 ResultExprTy = BaseTy->getPointeeType();
3282 llvm::Value *Idx = nullptr;
3283 if (IsLowerBound || E->getColonLoc().isInvalid()) {
3284 // Requesting lower bound or upper bound, but without provided length and
3285 // without ':' symbol for the default length -> length = 1.
3286 // Idx = LowerBound ?: 0;
3287 if (auto *LowerBound = E->getLowerBound()) {
3288 Idx = Builder.CreateIntCast(
3289 EmitScalarExpr(LowerBound), IntPtrTy,
3290 LowerBound->getType()->hasSignedIntegerRepresentation());
3292 Idx = llvm::ConstantInt::getNullValue(IntPtrTy);
3294 // Try to emit length or lower bound as constant. If this is possible, 1
3295 // is subtracted from constant length or lower bound. Otherwise, emit LLVM
3296 // IR (LB + Len) - 1.
3297 auto &C = CGM.getContext();
3298 auto *Length = E->getLength();
3299 llvm::APSInt ConstLength;
3301 // Idx = LowerBound + Length - 1;
3302 if (Length->isIntegerConstantExpr(ConstLength, C)) {
3303 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3306 auto *LowerBound = E->getLowerBound();
3307 llvm::APSInt ConstLowerBound(PointerWidthInBits, /*isUnsigned=*/false);
3308 if (LowerBound && LowerBound->isIntegerConstantExpr(ConstLowerBound, C)) {
3309 ConstLowerBound = ConstLowerBound.zextOrTrunc(PointerWidthInBits);
3310 LowerBound = nullptr;
3314 else if (!LowerBound)
3317 if (Length || LowerBound) {
3318 auto *LowerBoundVal =
3320 ? Builder.CreateIntCast(
3321 EmitScalarExpr(LowerBound), IntPtrTy,
3322 LowerBound->getType()->hasSignedIntegerRepresentation())
3323 : llvm::ConstantInt::get(IntPtrTy, ConstLowerBound);
3326 ? Builder.CreateIntCast(
3327 EmitScalarExpr(Length), IntPtrTy,
3328 Length->getType()->hasSignedIntegerRepresentation())
3329 : llvm::ConstantInt::get(IntPtrTy, ConstLength);
3330 Idx = Builder.CreateAdd(LowerBoundVal, LengthVal, "lb_add_len",
3332 !getLangOpts().isSignedOverflowDefined());
3333 if (Length && LowerBound) {
3334 Idx = Builder.CreateSub(
3335 Idx, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "idx_sub_1",
3336 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3339 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength + ConstLowerBound);
3341 // Idx = ArraySize - 1;
3342 QualType ArrayTy = BaseTy->isPointerType()
3343 ? E->getBase()->IgnoreParenImpCasts()->getType()
3345 if (auto *VAT = C.getAsVariableArrayType(ArrayTy)) {
3346 Length = VAT->getSizeExpr();
3347 if (Length->isIntegerConstantExpr(ConstLength, C))
3350 auto *CAT = C.getAsConstantArrayType(ArrayTy);
3351 ConstLength = CAT->getSize();
3354 auto *LengthVal = Builder.CreateIntCast(
3355 EmitScalarExpr(Length), IntPtrTy,
3356 Length->getType()->hasSignedIntegerRepresentation());
3357 Idx = Builder.CreateSub(
3358 LengthVal, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "len_sub_1",
3359 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3361 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3363 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength);
3369 Address EltPtr = Address::invalid();
3370 LValueBaseInfo BaseInfo;
3371 if (auto *VLA = getContext().getAsVariableArrayType(ResultExprTy)) {
3372 // The base must be a pointer, which is not an aggregate. Emit
3373 // it. It needs to be emitted first in case it's what captures
3376 emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, BaseTy,
3377 VLA->getElementType(), IsLowerBound);
3378 // The element count here is the total number of non-VLA elements.
3379 llvm::Value *NumElements = getVLASize(VLA).first;
3381 // Effectively, the multiply by the VLA size is part of the GEP.
3382 // GEP indexes are signed, and scaling an index isn't permitted to
3383 // signed-overflow, so we use the same semantics for our explicit
3384 // multiply. We suppress this if overflow is not undefined behavior.
3385 if (getLangOpts().isSignedOverflowDefined())
3386 Idx = Builder.CreateMul(Idx, NumElements);
3388 Idx = Builder.CreateNSWMul(Idx, NumElements);
3389 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(),
3390 !getLangOpts().isSignedOverflowDefined(),
3391 /*SignedIndices=*/false, E->getExprLoc());
3392 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3393 // If this is A[i] where A is an array, the frontend will have decayed the
3394 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3395 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3396 // "gep x, i" here. Emit one "gep A, 0, i".
3397 assert(Array->getType()->isArrayType() &&
3398 "Array to pointer decay must have array source type!");
3400 // For simple multidimensional array indexing, set the 'accessed' flag for
3401 // better bounds-checking of the base expression.
3402 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3403 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3405 ArrayLV = EmitLValue(Array);
3407 // Propagate the alignment from the array itself to the result.
3408 EltPtr = emitArraySubscriptGEP(
3409 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
3410 ResultExprTy, !getLangOpts().isSignedOverflowDefined(),
3411 /*SignedIndices=*/false, E->getExprLoc());
3412 BaseInfo = ArrayLV.getBaseInfo();
3414 Address Base = emitOMPArraySectionBase(*this, E->getBase(), BaseInfo,
3415 BaseTy, ResultExprTy, IsLowerBound);
3416 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy,
3417 !getLangOpts().isSignedOverflowDefined(),
3418 /*SignedIndices=*/false, E->getExprLoc());
3421 return MakeAddrLValue(EltPtr, ResultExprTy, BaseInfo);
3424 LValue CodeGenFunction::
3425 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
3426 // Emit the base vector as an l-value.
3429 // ExtVectorElementExpr's base can either be a vector or pointer to vector.
3431 // If it is a pointer to a vector, emit the address and form an lvalue with
3433 LValueBaseInfo BaseInfo;
3434 Address Ptr = EmitPointerWithAlignment(E->getBase(), &BaseInfo);
3435 const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
3436 Base = MakeAddrLValue(Ptr, PT->getPointeeType(), BaseInfo);
3437 Base.getQuals().removeObjCGCAttr();
3438 } else if (E->getBase()->isGLValue()) {
3439 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
3440 // emit the base as an lvalue.
3441 assert(E->getBase()->getType()->isVectorType());
3442 Base = EmitLValue(E->getBase());
3444 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
3445 assert(E->getBase()->getType()->isVectorType() &&
3446 "Result must be a vector");
3447 llvm::Value *Vec = EmitScalarExpr(E->getBase());
3449 // Store the vector to memory (because LValue wants an address).
3450 Address VecMem = CreateMemTemp(E->getBase()->getType());
3451 Builder.CreateStore(Vec, VecMem);
3452 Base = MakeAddrLValue(VecMem, E->getBase()->getType(),
3453 LValueBaseInfo(AlignmentSource::Decl, false));
3457 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers());
3459 // Encode the element access list into a vector of unsigned indices.
3460 SmallVector<uint32_t, 4> Indices;
3461 E->getEncodedElementAccess(Indices);
3463 if (Base.isSimple()) {
3464 llvm::Constant *CV =
3465 llvm::ConstantDataVector::get(getLLVMContext(), Indices);
3466 return LValue::MakeExtVectorElt(Base.getAddress(), CV, type,
3467 Base.getBaseInfo());
3469 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
3471 llvm::Constant *BaseElts = Base.getExtVectorElts();
3472 SmallVector<llvm::Constant *, 4> CElts;
3474 for (unsigned i = 0, e = Indices.size(); i != e; ++i)
3475 CElts.push_back(BaseElts->getAggregateElement(Indices[i]));
3476 llvm::Constant *CV = llvm::ConstantVector::get(CElts);
3477 return LValue::MakeExtVectorElt(Base.getExtVectorAddress(), CV, type,
3478 Base.getBaseInfo());
3481 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
3482 Expr *BaseExpr = E->getBase();
3483 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
3486 LValueBaseInfo BaseInfo;
3487 Address Addr = EmitPointerWithAlignment(BaseExpr, &BaseInfo);
3488 QualType PtrTy = BaseExpr->getType()->getPointeeType();
3489 SanitizerSet SkippedChecks;
3490 bool IsBaseCXXThis = IsWrappedCXXThis(BaseExpr);
3492 SkippedChecks.set(SanitizerKind::Alignment, true);
3493 if (IsBaseCXXThis || isa<DeclRefExpr>(BaseExpr))
3494 SkippedChecks.set(SanitizerKind::Null, true);
3495 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr.getPointer(), PtrTy,
3496 /*Alignment=*/CharUnits::Zero(), SkippedChecks);
3497 BaseLV = MakeAddrLValue(Addr, PtrTy, BaseInfo);
3499 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess);
3501 NamedDecl *ND = E->getMemberDecl();
3502 if (auto *Field = dyn_cast<FieldDecl>(ND)) {
3503 LValue LV = EmitLValueForField(BaseLV, Field);
3504 setObjCGCLValueClass(getContext(), E, LV);
3508 if (auto *VD = dyn_cast<VarDecl>(ND))
3509 return EmitGlobalVarDeclLValue(*this, E, VD);
3511 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
3512 return EmitFunctionDeclLValue(*this, E, FD);
3514 llvm_unreachable("Unhandled member declaration!");
3517 /// Given that we are currently emitting a lambda, emit an l-value for
3518 /// one of its members.
3519 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) {
3520 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent()->isLambda());
3521 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent() == Field->getParent());
3522 QualType LambdaTagType =
3523 getContext().getTagDeclType(Field->getParent());
3524 LValue LambdaLV = MakeNaturalAlignAddrLValue(CXXABIThisValue, LambdaTagType);
3525 return EmitLValueForField(LambdaLV, Field);
3528 /// Drill down to the storage of a field without walking into
3529 /// reference types.
3531 /// The resulting address doesn't necessarily have the right type.
3532 static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base,
3533 const FieldDecl *field) {
3534 const RecordDecl *rec = field->getParent();
3537 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
3540 // Adjust the alignment down to the given offset.
3541 // As a special case, if the LLVM field index is 0, we know that this
3543 assert((idx != 0 || CGF.getContext().getASTRecordLayout(rec)
3544 .getFieldOffset(field->getFieldIndex()) == 0) &&
3545 "LLVM field at index zero had non-zero offset?");
3547 auto &recLayout = CGF.getContext().getASTRecordLayout(rec);
3548 auto offsetInBits = recLayout.getFieldOffset(field->getFieldIndex());
3549 offset = CGF.getContext().toCharUnitsFromBits(offsetInBits);
3552 return CGF.Builder.CreateStructGEP(base, idx, offset, field->getName());
3555 static bool hasAnyVptr(const QualType Type, const ASTContext &Context) {
3556 const auto *RD = Type.getTypePtr()->getAsCXXRecordDecl();
3560 if (RD->isDynamicClass())
3563 for (const auto &Base : RD->bases())
3564 if (hasAnyVptr(Base.getType(), Context))
3567 for (const FieldDecl *Field : RD->fields())
3568 if (hasAnyVptr(Field->getType(), Context))
3574 LValue CodeGenFunction::EmitLValueForField(LValue base,
3575 const FieldDecl *field) {
3576 LValueBaseInfo BaseInfo = base.getBaseInfo();
3577 AlignmentSource fieldAlignSource =
3578 getFieldAlignmentSource(BaseInfo.getAlignmentSource());
3579 LValueBaseInfo FieldBaseInfo(fieldAlignSource, BaseInfo.getMayAlias());
3581 const RecordDecl *rec = field->getParent();
3582 if (rec->isUnion() || rec->hasAttr<MayAliasAttr>())
3583 FieldBaseInfo.setMayAlias(true);
3584 bool mayAlias = FieldBaseInfo.getMayAlias();
3586 if (field->isBitField()) {
3587 const CGRecordLayout &RL =
3588 CGM.getTypes().getCGRecordLayout(field->getParent());
3589 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field);
3590 Address Addr = base.getAddress();
3591 unsigned Idx = RL.getLLVMFieldNo(field);
3593 // For structs, we GEP to the field that the record layout suggests.
3594 Addr = Builder.CreateStructGEP(Addr, Idx, Info.StorageOffset,
3596 // Get the access type.
3597 llvm::Type *FieldIntTy =
3598 llvm::Type::getIntNTy(getLLVMContext(), Info.StorageSize);
3599 if (Addr.getElementType() != FieldIntTy)
3600 Addr = Builder.CreateElementBitCast(Addr, FieldIntTy);
3602 QualType fieldType =
3603 field->getType().withCVRQualifiers(base.getVRQualifiers());
3604 return LValue::MakeBitfield(Addr, Info, fieldType, FieldBaseInfo);
3607 QualType type = field->getType();
3608 Address addr = base.getAddress();
3609 unsigned cvr = base.getVRQualifiers();
3610 bool TBAAPath = CGM.getCodeGenOpts().StructPathTBAA;
3611 if (rec->isUnion()) {
3612 // For unions, there is no pointer adjustment.
3613 assert(!type->isReferenceType() && "union has reference member");
3614 // TODO: handle path-aware TBAA for union.
3617 const auto FieldType = field->getType();
3618 if (CGM.getCodeGenOpts().StrictVTablePointers &&
3619 hasAnyVptr(FieldType, getContext()))
3620 // Because unions can easily skip invariant.barriers, we need to add
3621 // a barrier every time CXXRecord field with vptr is referenced.
3622 addr = Address(Builder.CreateInvariantGroupBarrier(addr.getPointer()),
3623 addr.getAlignment());
3625 // For structs, we GEP to the field that the record layout suggests.
3626 addr = emitAddrOfFieldStorage(*this, addr, field);
3628 // If this is a reference field, load the reference right now.
3629 if (const ReferenceType *refType = type->getAs<ReferenceType>()) {
3630 llvm::LoadInst *load = Builder.CreateLoad(addr, "ref");
3631 if (cvr & Qualifiers::Volatile) load->setVolatile(true);
3633 // Loading the reference will disable path-aware TBAA.
3635 if (CGM.shouldUseTBAA()) {
3638 tbaa = CGM.getTBAAInfo(getContext().CharTy);
3640 tbaa = CGM.getTBAAInfo(type);
3642 CGM.DecorateInstructionWithTBAA(load, tbaa);
3646 type = refType->getPointeeType();
3648 CharUnits alignment =
3649 getNaturalTypeAlignment(type, &FieldBaseInfo, /*pointee*/ true);
3650 FieldBaseInfo.setMayAlias(false);
3651 addr = Address(load, alignment);
3653 // Qualifiers on the struct don't apply to the referencee, and
3654 // we'll pick up CVR from the actual type later, so reset these
3655 // additional qualifiers now.
3660 // Make sure that the address is pointing to the right type. This is critical
3661 // for both unions and structs. A union needs a bitcast, a struct element
3662 // will need a bitcast if the LLVM type laid out doesn't match the desired
3664 addr = Builder.CreateElementBitCast(addr,
3665 CGM.getTypes().ConvertTypeForMem(type),
3668 if (field->hasAttr<AnnotateAttr>())
3669 addr = EmitFieldAnnotations(field, addr);
3671 LValue LV = MakeAddrLValue(addr, type, FieldBaseInfo);
3672 LV.getQuals().addCVRQualifiers(cvr);
3674 const ASTRecordLayout &Layout =
3675 getContext().getASTRecordLayout(field->getParent());
3676 // Set the base type to be the base type of the base LValue and
3677 // update offset to be relative to the base type.
3678 LV.setTBAABaseType(mayAlias ? getContext().CharTy : base.getTBAABaseType());
3679 LV.setTBAAOffset(mayAlias ? 0 : base.getTBAAOffset() +
3680 Layout.getFieldOffset(field->getFieldIndex()) /
3681 getContext().getCharWidth());
3684 // __weak attribute on a field is ignored.
3685 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
3686 LV.getQuals().removeObjCGCAttr();
3688 // Fields of may_alias structs act like 'char' for TBAA purposes.
3689 // FIXME: this should get propagated down through anonymous structs
3691 if (mayAlias && LV.getTBAAInfo())
3692 LV.setTBAAInfo(CGM.getTBAAInfo(getContext().CharTy));
3698 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base,
3699 const FieldDecl *Field) {
3700 QualType FieldType = Field->getType();
3702 if (!FieldType->isReferenceType())
3703 return EmitLValueForField(Base, Field);
3705 Address V = emitAddrOfFieldStorage(*this, Base.getAddress(), Field);
3707 // Make sure that the address is pointing to the right type.
3708 llvm::Type *llvmType = ConvertTypeForMem(FieldType);
3709 V = Builder.CreateElementBitCast(V, llvmType, Field->getName());
3711 // TODO: access-path TBAA?
3712 LValueBaseInfo BaseInfo = Base.getBaseInfo();
3713 LValueBaseInfo FieldBaseInfo(
3714 getFieldAlignmentSource(BaseInfo.getAlignmentSource()),
3715 BaseInfo.getMayAlias());
3716 return MakeAddrLValue(V, FieldType, FieldBaseInfo);
3719 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
3720 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
3721 if (E->isFileScope()) {
3722 ConstantAddress GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E);
3723 return MakeAddrLValue(GlobalPtr, E->getType(), BaseInfo);
3725 if (E->getType()->isVariablyModifiedType())
3726 // make sure to emit the VLA size.
3727 EmitVariablyModifiedType(E->getType());
3729 Address DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
3730 const Expr *InitExpr = E->getInitializer();
3731 LValue Result = MakeAddrLValue(DeclPtr, E->getType(), BaseInfo);
3733 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(),
3739 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) {
3740 if (!E->isGLValue())
3741 // Initializing an aggregate temporary in C++11: T{...}.
3742 return EmitAggExprToLValue(E);
3744 // An lvalue initializer list must be initializing a reference.
3745 assert(E->isTransparent() && "non-transparent glvalue init list");
3746 return EmitLValue(E->getInit(0));
3749 /// Emit the operand of a glvalue conditional operator. This is either a glvalue
3750 /// or a (possibly-parenthesized) throw-expression. If this is a throw, no
3751 /// LValue is returned and the current block has been terminated.
3752 static Optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF,
3753 const Expr *Operand) {
3754 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) {
3755 CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false);
3759 return CGF.EmitLValue(Operand);
3762 LValue CodeGenFunction::
3763 EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) {
3764 if (!expr->isGLValue()) {
3765 // ?: here should be an aggregate.
3766 assert(hasAggregateEvaluationKind(expr->getType()) &&
3767 "Unexpected conditional operator!");
3768 return EmitAggExprToLValue(expr);
3771 OpaqueValueMapping binding(*this, expr);
3773 const Expr *condExpr = expr->getCond();
3775 if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
3776 const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr();
3777 if (!CondExprBool) std::swap(live, dead);
3779 if (!ContainsLabel(dead)) {
3780 // If the true case is live, we need to track its region.
3782 incrementProfileCounter(expr);
3783 return EmitLValue(live);
3787 llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true");
3788 llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false");
3789 llvm::BasicBlock *contBlock = createBasicBlock("cond.end");
3791 ConditionalEvaluation eval(*this);
3792 EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock, getProfileCount(expr));
3794 // Any temporaries created here are conditional.
3795 EmitBlock(lhsBlock);
3796 incrementProfileCounter(expr);
3798 Optional<LValue> lhs =
3799 EmitLValueOrThrowExpression(*this, expr->getTrueExpr());
3802 if (lhs && !lhs->isSimple())
3803 return EmitUnsupportedLValue(expr, "conditional operator");
3805 lhsBlock = Builder.GetInsertBlock();
3807 Builder.CreateBr(contBlock);
3809 // Any temporaries created here are conditional.
3810 EmitBlock(rhsBlock);
3812 Optional<LValue> rhs =
3813 EmitLValueOrThrowExpression(*this, expr->getFalseExpr());
3815 if (rhs && !rhs->isSimple())
3816 return EmitUnsupportedLValue(expr, "conditional operator");
3817 rhsBlock = Builder.GetInsertBlock();
3819 EmitBlock(contBlock);
3822 llvm::PHINode *phi = Builder.CreatePHI(lhs->getPointer()->getType(),
3824 phi->addIncoming(lhs->getPointer(), lhsBlock);
3825 phi->addIncoming(rhs->getPointer(), rhsBlock);
3826 Address result(phi, std::min(lhs->getAlignment(), rhs->getAlignment()));
3827 AlignmentSource alignSource =
3828 std::max(lhs->getBaseInfo().getAlignmentSource(),
3829 rhs->getBaseInfo().getAlignmentSource());
3830 bool MayAlias = lhs->getBaseInfo().getMayAlias() ||
3831 rhs->getBaseInfo().getMayAlias();
3832 return MakeAddrLValue(result, expr->getType(),
3833 LValueBaseInfo(alignSource, MayAlias));
3835 assert((lhs || rhs) &&
3836 "both operands of glvalue conditional are throw-expressions?");
3837 return lhs ? *lhs : *rhs;
3841 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference
3842 /// type. If the cast is to a reference, we can have the usual lvalue result,
3843 /// otherwise if a cast is needed by the code generator in an lvalue context,
3844 /// then it must mean that we need the address of an aggregate in order to
3845 /// access one of its members. This can happen for all the reasons that casts
3846 /// are permitted with aggregate result, including noop aggregate casts, and
3847 /// cast from scalar to union.
3848 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
3849 switch (E->getCastKind()) {
3852 case CK_ArrayToPointerDecay:
3853 case CK_FunctionToPointerDecay:
3854 case CK_NullToMemberPointer:
3855 case CK_NullToPointer:
3856 case CK_IntegralToPointer:
3857 case CK_PointerToIntegral:
3858 case CK_PointerToBoolean:
3859 case CK_VectorSplat:
3860 case CK_IntegralCast:
3861 case CK_BooleanToSignedIntegral:
3862 case CK_IntegralToBoolean:
3863 case CK_IntegralToFloating:
3864 case CK_FloatingToIntegral:
3865 case CK_FloatingToBoolean:
3866 case CK_FloatingCast:
3867 case CK_FloatingRealToComplex:
3868 case CK_FloatingComplexToReal:
3869 case CK_FloatingComplexToBoolean:
3870 case CK_FloatingComplexCast:
3871 case CK_FloatingComplexToIntegralComplex:
3872 case CK_IntegralRealToComplex:
3873 case CK_IntegralComplexToReal:
3874 case CK_IntegralComplexToBoolean:
3875 case CK_IntegralComplexCast:
3876 case CK_IntegralComplexToFloatingComplex:
3877 case CK_DerivedToBaseMemberPointer:
3878 case CK_BaseToDerivedMemberPointer:
3879 case CK_MemberPointerToBoolean:
3880 case CK_ReinterpretMemberPointer:
3881 case CK_AnyPointerToBlockPointerCast:
3882 case CK_ARCProduceObject:
3883 case CK_ARCConsumeObject:
3884 case CK_ARCReclaimReturnedObject:
3885 case CK_ARCExtendBlockObject:
3886 case CK_CopyAndAutoreleaseBlockObject:
3887 case CK_AddressSpaceConversion:
3888 case CK_IntToOCLSampler:
3889 return EmitUnsupportedLValue(E, "unexpected cast lvalue");
3892 llvm_unreachable("dependent cast kind in IR gen!");
3894 case CK_BuiltinFnToFnPtr:
3895 llvm_unreachable("builtin functions are handled elsewhere");
3897 // These are never l-values; just use the aggregate emission code.
3898 case CK_NonAtomicToAtomic:
3899 case CK_AtomicToNonAtomic:
3900 return EmitAggExprToLValue(E);
3903 LValue LV = EmitLValue(E->getSubExpr());
3904 Address V = LV.getAddress();
3905 const auto *DCE = cast<CXXDynamicCastExpr>(E);
3906 return MakeNaturalAlignAddrLValue(EmitDynamicCast(V, DCE), E->getType());
3909 case CK_ConstructorConversion:
3910 case CK_UserDefinedConversion:
3911 case CK_CPointerToObjCPointerCast:
3912 case CK_BlockPointerToObjCPointerCast:
3914 case CK_LValueToRValue:
3915 return EmitLValue(E->getSubExpr());
3917 case CK_UncheckedDerivedToBase:
3918 case CK_DerivedToBase: {
3919 const RecordType *DerivedClassTy =
3920 E->getSubExpr()->getType()->getAs<RecordType>();
3921 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
3923 LValue LV = EmitLValue(E->getSubExpr());
3924 Address This = LV.getAddress();
3926 // Perform the derived-to-base conversion
3927 Address Base = GetAddressOfBaseClass(
3928 This, DerivedClassDecl, E->path_begin(), E->path_end(),
3929 /*NullCheckValue=*/false, E->getExprLoc());
3931 return MakeAddrLValue(Base, E->getType(), LV.getBaseInfo());
3934 return EmitAggExprToLValue(E);
3935 case CK_BaseToDerived: {
3936 const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
3937 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
3939 LValue LV = EmitLValue(E->getSubExpr());
3941 // Perform the base-to-derived conversion
3943 GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
3944 E->path_begin(), E->path_end(),
3945 /*NullCheckValue=*/false);
3947 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is
3948 // performed and the object is not of the derived type.
3949 if (sanitizePerformTypeCheck())
3950 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(),
3951 Derived.getPointer(), E->getType());
3953 if (SanOpts.has(SanitizerKind::CFIDerivedCast))
3954 EmitVTablePtrCheckForCast(E->getType(), Derived.getPointer(),
3955 /*MayBeNull=*/false,
3956 CFITCK_DerivedCast, E->getLocStart());
3958 return MakeAddrLValue(Derived, E->getType(), LV.getBaseInfo());
3960 case CK_LValueBitCast: {
3961 // This must be a reinterpret_cast (or c-style equivalent).
3962 const auto *CE = cast<ExplicitCastExpr>(E);
3964 CGM.EmitExplicitCastExprType(CE, this);
3965 LValue LV = EmitLValue(E->getSubExpr());
3966 Address V = Builder.CreateBitCast(LV.getAddress(),
3967 ConvertType(CE->getTypeAsWritten()));
3969 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast))
3970 EmitVTablePtrCheckForCast(E->getType(), V.getPointer(),
3971 /*MayBeNull=*/false,
3972 CFITCK_UnrelatedCast, E->getLocStart());
3974 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo());
3976 case CK_ObjCObjectLValueCast: {
3977 LValue LV = EmitLValue(E->getSubExpr());
3978 Address V = Builder.CreateElementBitCast(LV.getAddress(),
3979 ConvertType(E->getType()));
3980 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo());
3982 case CK_ZeroToOCLQueue:
3983 llvm_unreachable("NULL to OpenCL queue lvalue cast is not valid");
3984 case CK_ZeroToOCLEvent:
3985 llvm_unreachable("NULL to OpenCL event lvalue cast is not valid");
3988 llvm_unreachable("Unhandled lvalue cast kind?");
3991 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
3992 assert(OpaqueValueMappingData::shouldBindAsLValue(e));
3993 return getOpaqueLValueMapping(e);
3996 RValue CodeGenFunction::EmitRValueForField(LValue LV,
3997 const FieldDecl *FD,
3998 SourceLocation Loc) {
3999 QualType FT = FD->getType();
4000 LValue FieldLV = EmitLValueForField(LV, FD);
4001 switch (getEvaluationKind(FT)) {
4003 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc));
4005 return FieldLV.asAggregateRValue();
4007 // This routine is used to load fields one-by-one to perform a copy, so
4008 // don't load reference fields.
4009 if (FD->getType()->isReferenceType())
4010 return RValue::get(FieldLV.getPointer());
4011 return EmitLoadOfLValue(FieldLV, Loc);
4013 llvm_unreachable("bad evaluation kind");
4016 //===--------------------------------------------------------------------===//
4017 // Expression Emission
4018 //===--------------------------------------------------------------------===//
4020 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
4021 ReturnValueSlot ReturnValue) {
4022 // Builtins never have block type.
4023 if (E->getCallee()->getType()->isBlockPointerType())
4024 return EmitBlockCallExpr(E, ReturnValue);
4026 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E))
4027 return EmitCXXMemberCallExpr(CE, ReturnValue);
4029 if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E))
4030 return EmitCUDAKernelCallExpr(CE, ReturnValue);
4032 if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E))
4033 if (const CXXMethodDecl *MD =
4034 dyn_cast_or_null<CXXMethodDecl>(CE->getCalleeDecl()))
4035 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
4037 CGCallee callee = EmitCallee(E->getCallee());
4039 if (callee.isBuiltin()) {
4040 return EmitBuiltinExpr(callee.getBuiltinDecl(), callee.getBuiltinID(),
4044 if (callee.isPseudoDestructor()) {
4045 return EmitCXXPseudoDestructorExpr(callee.getPseudoDestructorExpr());
4048 return EmitCall(E->getCallee()->getType(), callee, E, ReturnValue);
4051 /// Emit a CallExpr without considering whether it might be a subclass.
4052 RValue CodeGenFunction::EmitSimpleCallExpr(const CallExpr *E,
4053 ReturnValueSlot ReturnValue) {
4054 CGCallee Callee = EmitCallee(E->getCallee());
4055 return EmitCall(E->getCallee()->getType(), Callee, E, ReturnValue);
4058 static CGCallee EmitDirectCallee(CodeGenFunction &CGF, const FunctionDecl *FD) {
4059 if (auto builtinID = FD->getBuiltinID()) {
4060 return CGCallee::forBuiltin(builtinID, FD);
4063 llvm::Constant *calleePtr = EmitFunctionDeclPointer(CGF.CGM, FD);
4064 return CGCallee::forDirect(calleePtr, FD);
4067 CGCallee CodeGenFunction::EmitCallee(const Expr *E) {
4068 E = E->IgnoreParens();
4070 // Look through function-to-pointer decay.
4071 if (auto ICE = dyn_cast<ImplicitCastExpr>(E)) {
4072 if (ICE->getCastKind() == CK_FunctionToPointerDecay ||
4073 ICE->getCastKind() == CK_BuiltinFnToFnPtr) {
4074 return EmitCallee(ICE->getSubExpr());
4077 // Resolve direct calls.
4078 } else if (auto DRE = dyn_cast<DeclRefExpr>(E)) {
4079 if (auto FD = dyn_cast<FunctionDecl>(DRE->getDecl())) {
4080 return EmitDirectCallee(*this, FD);
4082 } else if (auto ME = dyn_cast<MemberExpr>(E)) {
4083 if (auto FD = dyn_cast<FunctionDecl>(ME->getMemberDecl())) {
4084 EmitIgnoredExpr(ME->getBase());
4085 return EmitDirectCallee(*this, FD);
4088 // Look through template substitutions.
4089 } else if (auto NTTP = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
4090 return EmitCallee(NTTP->getReplacement());
4092 // Treat pseudo-destructor calls differently.
4093 } else if (auto PDE = dyn_cast<CXXPseudoDestructorExpr>(E)) {
4094 return CGCallee::forPseudoDestructor(PDE);
4097 // Otherwise, we have an indirect reference.
4098 llvm::Value *calleePtr;
4099 QualType functionType;
4100 if (auto ptrType = E->getType()->getAs<PointerType>()) {
4101 calleePtr = EmitScalarExpr(E);
4102 functionType = ptrType->getPointeeType();
4104 functionType = E->getType();
4105 calleePtr = EmitLValue(E).getPointer();
4107 assert(functionType->isFunctionType());
4108 CGCalleeInfo calleeInfo(functionType->getAs<FunctionProtoType>(),
4109 E->getReferencedDeclOfCallee());
4110 CGCallee callee(calleeInfo, calleePtr);
4114 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
4115 // Comma expressions just emit their LHS then their RHS as an l-value.
4116 if (E->getOpcode() == BO_Comma) {
4117 EmitIgnoredExpr(E->getLHS());
4118 EnsureInsertPoint();
4119 return EmitLValue(E->getRHS());
4122 if (E->getOpcode() == BO_PtrMemD ||
4123 E->getOpcode() == BO_PtrMemI)
4124 return EmitPointerToDataMemberBinaryExpr(E);
4126 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
4128 // Note that in all of these cases, __block variables need the RHS
4129 // evaluated first just in case the variable gets moved by the RHS.
4131 switch (getEvaluationKind(E->getType())) {
4133 switch (E->getLHS()->getType().getObjCLifetime()) {
4134 case Qualifiers::OCL_Strong:
4135 return EmitARCStoreStrong(E, /*ignored*/ false).first;
4137 case Qualifiers::OCL_Autoreleasing:
4138 return EmitARCStoreAutoreleasing(E).first;
4140 // No reason to do any of these differently.
4141 case Qualifiers::OCL_None:
4142 case Qualifiers::OCL_ExplicitNone:
4143 case Qualifiers::OCL_Weak:
4147 RValue RV = EmitAnyExpr(E->getRHS());
4148 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store);
4150 EmitNullabilityCheck(LV, RV.getScalarVal(), E->getExprLoc());
4151 EmitStoreThroughLValue(RV, LV);
4156 return EmitComplexAssignmentLValue(E);
4159 return EmitAggExprToLValue(E);
4161 llvm_unreachable("bad evaluation kind");
4164 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
4165 RValue RV = EmitCallExpr(E);
4168 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4169 LValueBaseInfo(AlignmentSource::Decl, false));
4171 assert(E->getCallReturnType(getContext())->isReferenceType() &&
4172 "Can't have a scalar return unless the return type is a "
4175 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4178 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
4179 // FIXME: This shouldn't require another copy.
4180 return EmitAggExprToLValue(E);
4183 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
4184 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
4185 && "binding l-value to type which needs a temporary");
4186 AggValueSlot Slot = CreateAggTemp(E->getType());
4187 EmitCXXConstructExpr(E, Slot);
4188 return MakeAddrLValue(Slot.getAddress(), E->getType(),
4189 LValueBaseInfo(AlignmentSource::Decl, false));
4193 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
4194 return MakeNaturalAlignAddrLValue(EmitCXXTypeidExpr(E), E->getType());
4197 Address CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) {
4198 return Builder.CreateElementBitCast(CGM.GetAddrOfUuidDescriptor(E),
4199 ConvertType(E->getType()));
4202 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) {
4203 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType(),
4204 LValueBaseInfo(AlignmentSource::Decl, false));
4208 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
4209 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
4210 Slot.setExternallyDestructed();
4211 EmitAggExpr(E->getSubExpr(), Slot);
4212 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddress());
4213 return MakeAddrLValue(Slot.getAddress(), E->getType(),
4214 LValueBaseInfo(AlignmentSource::Decl, false));
4218 CodeGenFunction::EmitLambdaLValue(const LambdaExpr *E) {
4219 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
4220 EmitLambdaExpr(E, Slot);
4221 return MakeAddrLValue(Slot.getAddress(), E->getType(),
4222 LValueBaseInfo(AlignmentSource::Decl, false));
4225 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
4226 RValue RV = EmitObjCMessageExpr(E);
4229 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4230 LValueBaseInfo(AlignmentSource::Decl, false));
4232 assert(E->getMethodDecl()->getReturnType()->isReferenceType() &&
4233 "Can't have a scalar return unless the return type is a "
4236 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4239 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
4241 CGM.getObjCRuntime().GetAddrOfSelector(*this, E->getSelector());
4242 return MakeAddrLValue(V, E->getType(),
4243 LValueBaseInfo(AlignmentSource::Decl, false));
4246 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
4247 const ObjCIvarDecl *Ivar) {
4248 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
4251 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
4252 llvm::Value *BaseValue,
4253 const ObjCIvarDecl *Ivar,
4254 unsigned CVRQualifiers) {
4255 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
4256 Ivar, CVRQualifiers);
4259 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
4260 // FIXME: A lot of the code below could be shared with EmitMemberExpr.
4261 llvm::Value *BaseValue = nullptr;
4262 const Expr *BaseExpr = E->getBase();
4263 Qualifiers BaseQuals;
4266 BaseValue = EmitScalarExpr(BaseExpr);
4267 ObjectTy = BaseExpr->getType()->getPointeeType();
4268 BaseQuals = ObjectTy.getQualifiers();
4270 LValue BaseLV = EmitLValue(BaseExpr);
4271 BaseValue = BaseLV.getPointer();
4272 ObjectTy = BaseExpr->getType();
4273 BaseQuals = ObjectTy.getQualifiers();
4277 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
4278 BaseQuals.getCVRQualifiers());
4279 setObjCGCLValueClass(getContext(), E, LV);
4283 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
4284 // Can only get l-value for message expression returning aggregate type
4285 RValue RV = EmitAnyExprToTemp(E);
4286 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4287 LValueBaseInfo(AlignmentSource::Decl, false));
4290 RValue CodeGenFunction::EmitCall(QualType CalleeType, const CGCallee &OrigCallee,
4291 const CallExpr *E, ReturnValueSlot ReturnValue,
4292 llvm::Value *Chain) {
4293 // Get the actual function type. The callee type will always be a pointer to
4294 // function type or a block pointer type.
4295 assert(CalleeType->isFunctionPointerType() &&
4296 "Call must have function pointer type!");
4298 const Decl *TargetDecl = OrigCallee.getAbstractInfo().getCalleeDecl();
4300 if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl))
4301 // We can only guarantee that a function is called from the correct
4302 // context/function based on the appropriate target attributes,
4303 // so only check in the case where we have both always_inline and target
4304 // since otherwise we could be making a conditional call after a check for
4305 // the proper cpu features (and it won't cause code generation issues due to
4306 // function based code generation).
4307 if (TargetDecl->hasAttr<AlwaysInlineAttr>() &&
4308 TargetDecl->hasAttr<TargetAttr>())
4309 checkTargetFeatures(E, FD);
4311 CalleeType = getContext().getCanonicalType(CalleeType);
4313 const auto *FnType =
4314 cast<FunctionType>(cast<PointerType>(CalleeType)->getPointeeType());
4316 CGCallee Callee = OrigCallee;
4318 if (getLangOpts().CPlusPlus && SanOpts.has(SanitizerKind::Function) &&
4319 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
4320 if (llvm::Constant *PrefixSig =
4321 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) {
4322 SanitizerScope SanScope(this);
4323 llvm::Constant *FTRTTIConst =
4324 CGM.GetAddrOfRTTIDescriptor(QualType(FnType, 0), /*ForEH=*/true);
4325 llvm::Type *PrefixStructTyElems[] = {
4326 PrefixSig->getType(),
4327 FTRTTIConst->getType()
4329 llvm::StructType *PrefixStructTy = llvm::StructType::get(
4330 CGM.getLLVMContext(), PrefixStructTyElems, /*isPacked=*/true);
4332 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4334 llvm::Value *CalleePrefixStruct = Builder.CreateBitCast(
4335 CalleePtr, llvm::PointerType::getUnqual(PrefixStructTy));
4336 llvm::Value *CalleeSigPtr =
4337 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 0);
4338 llvm::Value *CalleeSig =
4339 Builder.CreateAlignedLoad(CalleeSigPtr, getIntAlign());
4340 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig);
4342 llvm::BasicBlock *Cont = createBasicBlock("cont");
4343 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck");
4344 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont);
4346 EmitBlock(TypeCheck);
4347 llvm::Value *CalleeRTTIPtr =
4348 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 1);
4349 llvm::Value *CalleeRTTI =
4350 Builder.CreateAlignedLoad(CalleeRTTIPtr, getPointerAlign());
4351 llvm::Value *CalleeRTTIMatch =
4352 Builder.CreateICmpEQ(CalleeRTTI, FTRTTIConst);
4353 llvm::Constant *StaticData[] = {
4354 EmitCheckSourceLocation(E->getLocStart()),
4355 EmitCheckTypeDescriptor(CalleeType)
4357 EmitCheck(std::make_pair(CalleeRTTIMatch, SanitizerKind::Function),
4358 SanitizerHandler::FunctionTypeMismatch, StaticData, CalleePtr);
4360 Builder.CreateBr(Cont);
4365 // If we are checking indirect calls and this call is indirect, check that the
4366 // function pointer is a member of the bit set for the function type.
4367 if (SanOpts.has(SanitizerKind::CFIICall) &&
4368 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
4369 SanitizerScope SanScope(this);
4370 EmitSanitizerStatReport(llvm::SanStat_CFI_ICall);
4372 llvm::Metadata *MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0));
4373 llvm::Value *TypeId = llvm::MetadataAsValue::get(getLLVMContext(), MD);
4375 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4376 llvm::Value *CastedCallee = Builder.CreateBitCast(CalleePtr, Int8PtrTy);
4377 llvm::Value *TypeTest = Builder.CreateCall(
4378 CGM.getIntrinsic(llvm::Intrinsic::type_test), {CastedCallee, TypeId});
4380 auto CrossDsoTypeId = CGM.CreateCrossDsoCfiTypeId(MD);
4381 llvm::Constant *StaticData[] = {
4382 llvm::ConstantInt::get(Int8Ty, CFITCK_ICall),
4383 EmitCheckSourceLocation(E->getLocStart()),
4384 EmitCheckTypeDescriptor(QualType(FnType, 0)),
4386 if (CGM.getCodeGenOpts().SanitizeCfiCrossDso && CrossDsoTypeId) {
4387 EmitCfiSlowPathCheck(SanitizerKind::CFIICall, TypeTest, CrossDsoTypeId,
4388 CastedCallee, StaticData);
4390 EmitCheck(std::make_pair(TypeTest, SanitizerKind::CFIICall),
4391 SanitizerHandler::CFICheckFail, StaticData,
4392 {CastedCallee, llvm::UndefValue::get(IntPtrTy)});
4398 Args.add(RValue::get(Builder.CreateBitCast(Chain, CGM.VoidPtrTy)),
4399 CGM.getContext().VoidPtrTy);
4401 // C++17 requires that we evaluate arguments to a call using assignment syntax
4402 // right-to-left, and that we evaluate arguments to certain other operators
4403 // left-to-right. Note that we allow this to override the order dictated by
4404 // the calling convention on the MS ABI, which means that parameter
4405 // destruction order is not necessarily reverse construction order.
4406 // FIXME: Revisit this based on C++ committee response to unimplementability.
4407 EvaluationOrder Order = EvaluationOrder::Default;
4408 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(E)) {
4409 if (OCE->isAssignmentOp())
4410 Order = EvaluationOrder::ForceRightToLeft;
4412 switch (OCE->getOperator()) {
4414 case OO_GreaterGreater:
4419 Order = EvaluationOrder::ForceLeftToRight;
4427 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), E->arguments(),
4428 E->getDirectCallee(), /*ParamsToSkip*/ 0, Order);
4430 const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeFreeFunctionCall(
4431 Args, FnType, /*isChainCall=*/Chain);
4434 // If the expression that denotes the called function has a type
4435 // that does not include a prototype, [the default argument
4436 // promotions are performed]. If the number of arguments does not
4437 // equal the number of parameters, the behavior is undefined. If
4438 // the function is defined with a type that includes a prototype,
4439 // and either the prototype ends with an ellipsis (, ...) or the
4440 // types of the arguments after promotion are not compatible with
4441 // the types of the parameters, the behavior is undefined. If the
4442 // function is defined with a type that does not include a
4443 // prototype, and the types of the arguments after promotion are
4444 // not compatible with those of the parameters after promotion,
4445 // the behavior is undefined [except in some trivial cases].
4446 // That is, in the general case, we should assume that a call
4447 // through an unprototyped function type works like a *non-variadic*
4448 // call. The way we make this work is to cast to the exact type
4449 // of the promoted arguments.
4451 // Chain calls use this same code path to add the invisible chain parameter
4452 // to the function type.
4453 if (isa<FunctionNoProtoType>(FnType) || Chain) {
4454 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo);
4455 CalleeTy = CalleeTy->getPointerTo();
4457 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4458 CalleePtr = Builder.CreateBitCast(CalleePtr, CalleeTy, "callee.knr.cast");
4459 Callee.setFunctionPointer(CalleePtr);
4462 return EmitCall(FnInfo, Callee, ReturnValue, Args);
4465 LValue CodeGenFunction::
4466 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
4467 Address BaseAddr = Address::invalid();
4468 if (E->getOpcode() == BO_PtrMemI) {
4469 BaseAddr = EmitPointerWithAlignment(E->getLHS());
4471 BaseAddr = EmitLValue(E->getLHS()).getAddress();
4474 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
4476 const MemberPointerType *MPT
4477 = E->getRHS()->getType()->getAs<MemberPointerType>();
4479 LValueBaseInfo BaseInfo;
4480 Address MemberAddr =
4481 EmitCXXMemberDataPointerAddress(E, BaseAddr, OffsetV, MPT, &BaseInfo);
4483 return MakeAddrLValue(MemberAddr, MPT->getPointeeType(), BaseInfo);
4486 /// Given the address of a temporary variable, produce an r-value of
4488 RValue CodeGenFunction::convertTempToRValue(Address addr,
4490 SourceLocation loc) {
4491 LValue lvalue = MakeAddrLValue(addr, type,
4492 LValueBaseInfo(AlignmentSource::Decl, false));
4493 switch (getEvaluationKind(type)) {
4495 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc));
4497 return lvalue.asAggregateRValue();
4499 return RValue::get(EmitLoadOfScalar(lvalue, loc));
4501 llvm_unreachable("bad evaluation kind");
4504 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) {
4505 assert(Val->getType()->isFPOrFPVectorTy());
4506 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val))
4509 llvm::MDBuilder MDHelper(getLLVMContext());
4510 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy);
4512 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node);
4516 struct LValueOrRValue {
4522 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF,
4523 const PseudoObjectExpr *E,
4525 AggValueSlot slot) {
4526 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
4528 // Find the result expression, if any.
4529 const Expr *resultExpr = E->getResultExpr();
4530 LValueOrRValue result;
4532 for (PseudoObjectExpr::const_semantics_iterator
4533 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
4534 const Expr *semantic = *i;
4536 // If this semantic expression is an opaque value, bind it
4537 // to the result of its source expression.
4538 if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
4540 // If this is the result expression, we may need to evaluate
4541 // directly into the slot.
4542 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
4544 if (ov == resultExpr && ov->isRValue() && !forLValue &&
4545 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) {
4546 CGF.EmitAggExpr(ov->getSourceExpr(), slot);
4547 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
4548 LValue LV = CGF.MakeAddrLValue(slot.getAddress(), ov->getType(),
4550 opaqueData = OVMA::bind(CGF, ov, LV);
4551 result.RV = slot.asRValue();
4553 // Otherwise, emit as normal.
4555 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
4557 // If this is the result, also evaluate the result now.
4558 if (ov == resultExpr) {
4560 result.LV = CGF.EmitLValue(ov);
4562 result.RV = CGF.EmitAnyExpr(ov, slot);
4566 opaques.push_back(opaqueData);
4568 // Otherwise, if the expression is the result, evaluate it
4569 // and remember the result.
4570 } else if (semantic == resultExpr) {
4572 result.LV = CGF.EmitLValue(semantic);
4574 result.RV = CGF.EmitAnyExpr(semantic, slot);
4576 // Otherwise, evaluate the expression in an ignored context.
4578 CGF.EmitIgnoredExpr(semantic);
4582 // Unbind all the opaques now.
4583 for (unsigned i = 0, e = opaques.size(); i != e; ++i)
4584 opaques[i].unbind(CGF);
4589 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E,
4590 AggValueSlot slot) {
4591 return emitPseudoObjectExpr(*this, E, false, slot).RV;
4594 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) {
4595 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV;