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 llvm::Value *ArraySize,
66 bool CastToDefaultAddrSpace) {
67 auto Alloca = CreateTempAlloca(Ty, Name, ArraySize);
68 Alloca->setAlignment(Align.getQuantity());
69 llvm::Value *V = Alloca;
70 // Alloca always returns a pointer in alloca address space, which may
71 // be different from the type defined by the language. For example,
72 // in C++ the auto variables are in the default address space. Therefore
73 // cast alloca to the default address space when necessary.
74 if (CastToDefaultAddrSpace && getASTAllocaAddressSpace() != LangAS::Default) {
75 auto DestAddrSpace = getContext().getTargetAddressSpace(LangAS::Default);
76 V = getTargetHooks().performAddrSpaceCast(
77 *this, V, getASTAllocaAddressSpace(), LangAS::Default,
78 Ty->getPointerTo(DestAddrSpace), /*non-null*/ true);
81 return Address(V, Align);
84 /// CreateTempAlloca - This creates an alloca and inserts it into the entry
85 /// block if \p ArraySize is nullptr, otherwise inserts it at the current
86 /// insertion point of the builder.
87 llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty,
89 llvm::Value *ArraySize) {
91 return Builder.CreateAlloca(Ty, ArraySize, Name);
92 return new llvm::AllocaInst(Ty, CGM.getDataLayout().getAllocaAddrSpace(),
93 ArraySize, Name, AllocaInsertPt);
96 /// CreateDefaultAlignTempAlloca - This creates an alloca with the
97 /// default alignment of the corresponding LLVM type, which is *not*
98 /// guaranteed to be related in any way to the expected alignment of
99 /// an AST type that might have been lowered to Ty.
100 Address CodeGenFunction::CreateDefaultAlignTempAlloca(llvm::Type *Ty,
103 CharUnits::fromQuantity(CGM.getDataLayout().getABITypeAlignment(Ty));
104 return CreateTempAlloca(Ty, Align, Name);
107 void CodeGenFunction::InitTempAlloca(Address Var, llvm::Value *Init) {
108 assert(isa<llvm::AllocaInst>(Var.getPointer()));
109 auto *Store = new llvm::StoreInst(Init, Var.getPointer());
110 Store->setAlignment(Var.getAlignment().getQuantity());
111 llvm::BasicBlock *Block = AllocaInsertPt->getParent();
112 Block->getInstList().insertAfter(AllocaInsertPt->getIterator(), Store);
115 Address CodeGenFunction::CreateIRTemp(QualType Ty, const Twine &Name) {
116 CharUnits Align = getContext().getTypeAlignInChars(Ty);
117 return CreateTempAlloca(ConvertType(Ty), Align, Name);
120 Address CodeGenFunction::CreateMemTemp(QualType Ty, const Twine &Name,
121 bool CastToDefaultAddrSpace) {
122 // FIXME: Should we prefer the preferred type alignment here?
123 return CreateMemTemp(Ty, getContext().getTypeAlignInChars(Ty), Name,
124 CastToDefaultAddrSpace);
127 Address CodeGenFunction::CreateMemTemp(QualType Ty, CharUnits Align,
129 bool CastToDefaultAddrSpace) {
130 return CreateTempAlloca(ConvertTypeForMem(Ty), Align, Name, nullptr,
131 CastToDefaultAddrSpace);
134 /// EvaluateExprAsBool - Perform the usual unary conversions on the specified
135 /// expression and compare the result against zero, returning an Int1Ty value.
136 llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
137 PGO.setCurrentStmt(E);
138 if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) {
139 llvm::Value *MemPtr = EmitScalarExpr(E);
140 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT);
143 QualType BoolTy = getContext().BoolTy;
144 SourceLocation Loc = E->getExprLoc();
145 if (!E->getType()->isAnyComplexType())
146 return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy, Loc);
148 return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(), BoolTy,
152 /// EmitIgnoredExpr - Emit code to compute the specified expression,
153 /// ignoring the result.
154 void CodeGenFunction::EmitIgnoredExpr(const Expr *E) {
156 return (void) EmitAnyExpr(E, AggValueSlot::ignored(), true);
158 // Just emit it as an l-value and drop the result.
162 /// EmitAnyExpr - Emit code to compute the specified expression which
163 /// can have any type. The result is returned as an RValue struct.
164 /// If this is an aggregate expression, AggSlot indicates where the
165 /// result should be returned.
166 RValue CodeGenFunction::EmitAnyExpr(const Expr *E,
167 AggValueSlot aggSlot,
169 switch (getEvaluationKind(E->getType())) {
171 return RValue::get(EmitScalarExpr(E, ignoreResult));
173 return RValue::getComplex(EmitComplexExpr(E, ignoreResult, ignoreResult));
175 if (!ignoreResult && aggSlot.isIgnored())
176 aggSlot = CreateAggTemp(E->getType(), "agg-temp");
177 EmitAggExpr(E, aggSlot);
178 return aggSlot.asRValue();
180 llvm_unreachable("bad evaluation kind");
183 /// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will
184 /// always be accessible even if no aggregate location is provided.
185 RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) {
186 AggValueSlot AggSlot = AggValueSlot::ignored();
188 if (hasAggregateEvaluationKind(E->getType()))
189 AggSlot = CreateAggTemp(E->getType(), "agg.tmp");
190 return EmitAnyExpr(E, AggSlot);
193 /// EmitAnyExprToMem - Evaluate an expression into a given memory
195 void CodeGenFunction::EmitAnyExprToMem(const Expr *E,
199 // FIXME: This function should take an LValue as an argument.
200 switch (getEvaluationKind(E->getType())) {
202 EmitComplexExprIntoLValue(E, MakeAddrLValue(Location, E->getType()),
206 case TEK_Aggregate: {
207 EmitAggExpr(E, AggValueSlot::forAddr(Location, Quals,
208 AggValueSlot::IsDestructed_t(IsInit),
209 AggValueSlot::DoesNotNeedGCBarriers,
210 AggValueSlot::IsAliased_t(!IsInit)));
215 RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false));
216 LValue LV = MakeAddrLValue(Location, E->getType());
217 EmitStoreThroughLValue(RV, LV);
221 llvm_unreachable("bad evaluation kind");
225 pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M,
226 const Expr *E, Address ReferenceTemporary) {
227 // Objective-C++ ARC:
228 // If we are binding a reference to a temporary that has ownership, we
229 // need to perform retain/release operations on the temporary.
231 // FIXME: This should be looking at E, not M.
232 if (auto Lifetime = M->getType().getObjCLifetime()) {
234 case Qualifiers::OCL_None:
235 case Qualifiers::OCL_ExplicitNone:
236 // Carry on to normal cleanup handling.
239 case Qualifiers::OCL_Autoreleasing:
240 // Nothing to do; cleaned up by an autorelease pool.
243 case Qualifiers::OCL_Strong:
244 case Qualifiers::OCL_Weak:
245 switch (StorageDuration Duration = M->getStorageDuration()) {
247 // Note: we intentionally do not register a cleanup to release
248 // the object on program termination.
252 // FIXME: We should probably register a cleanup in this case.
256 case SD_FullExpression:
257 CodeGenFunction::Destroyer *Destroy;
258 CleanupKind CleanupKind;
259 if (Lifetime == Qualifiers::OCL_Strong) {
260 const ValueDecl *VD = M->getExtendingDecl();
262 VD && isa<VarDecl>(VD) && VD->hasAttr<ObjCPreciseLifetimeAttr>();
263 CleanupKind = CGF.getARCCleanupKind();
264 Destroy = Precise ? &CodeGenFunction::destroyARCStrongPrecise
265 : &CodeGenFunction::destroyARCStrongImprecise;
267 // __weak objects always get EH cleanups; otherwise, exceptions
268 // could cause really nasty crashes instead of mere leaks.
269 CleanupKind = NormalAndEHCleanup;
270 Destroy = &CodeGenFunction::destroyARCWeak;
272 if (Duration == SD_FullExpression)
273 CGF.pushDestroy(CleanupKind, ReferenceTemporary,
274 M->getType(), *Destroy,
275 CleanupKind & EHCleanup);
277 CGF.pushLifetimeExtendedDestroy(CleanupKind, ReferenceTemporary,
279 *Destroy, CleanupKind & EHCleanup);
283 llvm_unreachable("temporary cannot have dynamic storage duration");
285 llvm_unreachable("unknown storage duration");
289 CXXDestructorDecl *ReferenceTemporaryDtor = nullptr;
290 if (const RecordType *RT =
291 E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
292 // Get the destructor for the reference temporary.
293 auto *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
294 if (!ClassDecl->hasTrivialDestructor())
295 ReferenceTemporaryDtor = ClassDecl->getDestructor();
298 if (!ReferenceTemporaryDtor)
301 // Call the destructor for the temporary.
302 switch (M->getStorageDuration()) {
305 llvm::Constant *CleanupFn;
306 llvm::Constant *CleanupArg;
307 if (E->getType()->isArrayType()) {
308 CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper(
309 ReferenceTemporary, E->getType(),
310 CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions,
311 dyn_cast_or_null<VarDecl>(M->getExtendingDecl()));
312 CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy);
314 CleanupFn = CGF.CGM.getAddrOfCXXStructor(ReferenceTemporaryDtor,
315 StructorType::Complete);
316 CleanupArg = cast<llvm::Constant>(ReferenceTemporary.getPointer());
318 CGF.CGM.getCXXABI().registerGlobalDtor(
319 CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg);
323 case SD_FullExpression:
324 CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(),
325 CodeGenFunction::destroyCXXObject,
326 CGF.getLangOpts().Exceptions);
330 CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup,
331 ReferenceTemporary, E->getType(),
332 CodeGenFunction::destroyCXXObject,
333 CGF.getLangOpts().Exceptions);
337 llvm_unreachable("temporary cannot have dynamic storage duration");
342 createReferenceTemporary(CodeGenFunction &CGF,
343 const MaterializeTemporaryExpr *M, const Expr *Inner) {
344 switch (M->getStorageDuration()) {
345 case SD_FullExpression:
347 // If we have a constant temporary array or record try to promote it into a
348 // constant global under the same rules a normal constant would've been
349 // promoted. This is easier on the optimizer and generally emits fewer
351 QualType Ty = Inner->getType();
352 if (CGF.CGM.getCodeGenOpts().MergeAllConstants &&
353 (Ty->isArrayType() || Ty->isRecordType()) &&
354 CGF.CGM.isTypeConstant(Ty, true))
355 if (llvm::Constant *Init = CGF.CGM.EmitConstantExpr(Inner, Ty, &CGF)) {
356 auto *GV = new llvm::GlobalVariable(
357 CGF.CGM.getModule(), Init->getType(), /*isConstant=*/true,
358 llvm::GlobalValue::PrivateLinkage, Init, ".ref.tmp");
359 CharUnits alignment = CGF.getContext().getTypeAlignInChars(Ty);
360 GV->setAlignment(alignment.getQuantity());
361 // FIXME: Should we put the new global into a COMDAT?
362 return Address(GV, alignment);
364 return CGF.CreateMemTemp(Ty, "ref.tmp");
368 return CGF.CGM.GetAddrOfGlobalTemporary(M, Inner);
371 llvm_unreachable("temporary can't have dynamic storage duration");
373 llvm_unreachable("unknown storage duration");
376 LValue CodeGenFunction::
377 EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *M) {
378 const Expr *E = M->GetTemporaryExpr();
380 // FIXME: ideally this would use EmitAnyExprToMem, however, we cannot do so
381 // as that will cause the lifetime adjustment to be lost for ARC
382 auto ownership = M->getType().getObjCLifetime();
383 if (ownership != Qualifiers::OCL_None &&
384 ownership != Qualifiers::OCL_ExplicitNone) {
385 Address Object = createReferenceTemporary(*this, M, E);
386 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) {
387 Object = Address(llvm::ConstantExpr::getBitCast(Var,
388 ConvertTypeForMem(E->getType())
389 ->getPointerTo(Object.getAddressSpace())),
390 Object.getAlignment());
392 // createReferenceTemporary will promote the temporary to a global with a
393 // constant initializer if it can. It can only do this to a value of
394 // ARC-manageable type if the value is global and therefore "immune" to
395 // ref-counting operations. Therefore we have no need to emit either a
396 // dynamic initialization or a cleanup and we can just return the address
398 if (Var->hasInitializer())
399 return MakeAddrLValue(Object, M->getType(),
400 LValueBaseInfo(AlignmentSource::Decl, false));
402 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
404 LValue RefTempDst = MakeAddrLValue(Object, M->getType(),
405 LValueBaseInfo(AlignmentSource::Decl,
408 switch (getEvaluationKind(E->getType())) {
409 default: llvm_unreachable("expected scalar or aggregate expression");
411 EmitScalarInit(E, M->getExtendingDecl(), RefTempDst, false);
413 case TEK_Aggregate: {
414 EmitAggExpr(E, AggValueSlot::forAddr(Object,
415 E->getType().getQualifiers(),
416 AggValueSlot::IsDestructed,
417 AggValueSlot::DoesNotNeedGCBarriers,
418 AggValueSlot::IsNotAliased));
423 pushTemporaryCleanup(*this, M, E, Object);
427 SmallVector<const Expr *, 2> CommaLHSs;
428 SmallVector<SubobjectAdjustment, 2> Adjustments;
429 E = E->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
431 for (const auto &Ignored : CommaLHSs)
432 EmitIgnoredExpr(Ignored);
434 if (const auto *opaque = dyn_cast<OpaqueValueExpr>(E)) {
435 if (opaque->getType()->isRecordType()) {
436 assert(Adjustments.empty());
437 return EmitOpaqueValueLValue(opaque);
441 // Create and initialize the reference temporary.
442 Address Object = createReferenceTemporary(*this, M, E);
443 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object.getPointer())) {
444 Object = Address(llvm::ConstantExpr::getBitCast(
445 Var, ConvertTypeForMem(E->getType())->getPointerTo()),
446 Object.getAlignment());
447 // If the temporary is a global and has a constant initializer or is a
448 // constant temporary that we promoted to a global, we may have already
450 if (!Var->hasInitializer()) {
451 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
452 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
455 switch (M->getStorageDuration()) {
457 case SD_FullExpression:
458 if (auto *Size = EmitLifetimeStart(
459 CGM.getDataLayout().getTypeAllocSize(Object.getElementType()),
460 Object.getPointer())) {
461 if (M->getStorageDuration() == SD_Automatic)
462 pushCleanupAfterFullExpr<CallLifetimeEnd>(NormalEHLifetimeMarker,
465 pushFullExprCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker, Object,
472 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
474 pushTemporaryCleanup(*this, M, E, Object);
476 // Perform derived-to-base casts and/or field accesses, to get from the
477 // temporary object we created (and, potentially, for which we extended
478 // the lifetime) to the subobject we're binding the reference to.
479 for (unsigned I = Adjustments.size(); I != 0; --I) {
480 SubobjectAdjustment &Adjustment = Adjustments[I-1];
481 switch (Adjustment.Kind) {
482 case SubobjectAdjustment::DerivedToBaseAdjustment:
484 GetAddressOfBaseClass(Object, Adjustment.DerivedToBase.DerivedClass,
485 Adjustment.DerivedToBase.BasePath->path_begin(),
486 Adjustment.DerivedToBase.BasePath->path_end(),
487 /*NullCheckValue=*/ false, E->getExprLoc());
490 case SubobjectAdjustment::FieldAdjustment: {
491 LValue LV = MakeAddrLValue(Object, E->getType(),
492 LValueBaseInfo(AlignmentSource::Decl, false));
493 LV = EmitLValueForField(LV, Adjustment.Field);
494 assert(LV.isSimple() &&
495 "materialized temporary field is not a simple lvalue");
496 Object = LV.getAddress();
500 case SubobjectAdjustment::MemberPointerAdjustment: {
501 llvm::Value *Ptr = EmitScalarExpr(Adjustment.Ptr.RHS);
502 Object = EmitCXXMemberDataPointerAddress(E, Object, Ptr,
509 return MakeAddrLValue(Object, M->getType(),
510 LValueBaseInfo(AlignmentSource::Decl, false));
514 CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E) {
515 // Emit the expression as an lvalue.
516 LValue LV = EmitLValue(E);
517 assert(LV.isSimple());
518 llvm::Value *Value = LV.getPointer();
520 if (sanitizePerformTypeCheck() && !E->getType()->isFunctionType()) {
521 // C++11 [dcl.ref]p5 (as amended by core issue 453):
522 // If a glvalue to which a reference is directly bound designates neither
523 // an existing object or function of an appropriate type nor a region of
524 // storage of suitable size and alignment to contain an object of the
525 // reference's type, the behavior is undefined.
526 QualType Ty = E->getType();
527 EmitTypeCheck(TCK_ReferenceBinding, E->getExprLoc(), Value, Ty);
530 return RValue::get(Value);
534 /// getAccessedFieldNo - Given an encoded value and a result number, return the
535 /// input field number being accessed.
536 unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
537 const llvm::Constant *Elts) {
538 return cast<llvm::ConstantInt>(Elts->getAggregateElement(Idx))
542 /// Emit the hash_16_bytes function from include/llvm/ADT/Hashing.h.
543 static llvm::Value *emitHash16Bytes(CGBuilderTy &Builder, llvm::Value *Low,
545 llvm::Value *KMul = Builder.getInt64(0x9ddfea08eb382d69ULL);
546 llvm::Value *K47 = Builder.getInt64(47);
547 llvm::Value *A0 = Builder.CreateMul(Builder.CreateXor(Low, High), KMul);
548 llvm::Value *A1 = Builder.CreateXor(Builder.CreateLShr(A0, K47), A0);
549 llvm::Value *B0 = Builder.CreateMul(Builder.CreateXor(High, A1), KMul);
550 llvm::Value *B1 = Builder.CreateXor(Builder.CreateLShr(B0, K47), B0);
551 return Builder.CreateMul(B1, KMul);
554 bool CodeGenFunction::sanitizePerformTypeCheck() const {
555 return SanOpts.has(SanitizerKind::Null) |
556 SanOpts.has(SanitizerKind::Alignment) |
557 SanOpts.has(SanitizerKind::ObjectSize) |
558 SanOpts.has(SanitizerKind::Vptr);
561 void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc,
562 llvm::Value *Ptr, QualType Ty,
564 SanitizerSet SkippedChecks) {
565 if (!sanitizePerformTypeCheck())
568 // Don't check pointers outside the default address space. The null check
569 // isn't correct, the object-size check isn't supported by LLVM, and we can't
570 // communicate the addresses to the runtime handler for the vptr check.
571 if (Ptr->getType()->getPointerAddressSpace())
574 // Don't check pointers to volatile data. The behavior here is implementation-
576 if (Ty.isVolatileQualified())
579 SanitizerScope SanScope(this);
581 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 3> Checks;
582 llvm::BasicBlock *Done = nullptr;
584 // Quickly determine whether we have a pointer to an alloca. It's possible
585 // to skip null checks, and some alignment checks, for these pointers. This
586 // can reduce compile-time significantly.
588 dyn_cast<llvm::AllocaInst>(Ptr->stripPointerCastsNoFollowAliases());
590 bool AllowNullPointers = TCK == TCK_DowncastPointer || TCK == TCK_Upcast ||
591 TCK == TCK_UpcastToVirtualBase;
592 if ((SanOpts.has(SanitizerKind::Null) || AllowNullPointers) &&
593 !SkippedChecks.has(SanitizerKind::Null) && !PtrToAlloca) {
594 // The glvalue must not be an empty glvalue.
595 llvm::Value *IsNonNull = Builder.CreateIsNotNull(Ptr);
597 // The IR builder can constant-fold the null check if the pointer points to
600 IsNonNull == llvm::ConstantInt::getTrue(getLLVMContext());
602 // Skip the null check if the pointer is known to be non-null.
604 if (AllowNullPointers) {
605 // When performing pointer casts, it's OK if the value is null.
606 // Skip the remaining checks in that case.
607 Done = createBasicBlock("null");
608 llvm::BasicBlock *Rest = createBasicBlock("not.null");
609 Builder.CreateCondBr(IsNonNull, Rest, Done);
612 Checks.push_back(std::make_pair(IsNonNull, SanitizerKind::Null));
617 if (SanOpts.has(SanitizerKind::ObjectSize) &&
618 !SkippedChecks.has(SanitizerKind::ObjectSize) &&
619 !Ty->isIncompleteType()) {
620 uint64_t Size = getContext().getTypeSizeInChars(Ty).getQuantity();
622 // The glvalue must refer to a large enough storage region.
623 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation
625 // FIXME: Get object address space
626 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy };
627 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys);
628 llvm::Value *Min = Builder.getFalse();
629 llvm::Value *NullIsUnknown = Builder.getFalse();
630 llvm::Value *CastAddr = Builder.CreateBitCast(Ptr, Int8PtrTy);
631 llvm::Value *LargeEnough = Builder.CreateICmpUGE(
632 Builder.CreateCall(F, {CastAddr, Min, NullIsUnknown}),
633 llvm::ConstantInt::get(IntPtrTy, Size));
634 Checks.push_back(std::make_pair(LargeEnough, SanitizerKind::ObjectSize));
637 uint64_t AlignVal = 0;
639 if (SanOpts.has(SanitizerKind::Alignment) &&
640 !SkippedChecks.has(SanitizerKind::Alignment)) {
641 AlignVal = Alignment.getQuantity();
642 if (!Ty->isIncompleteType() && !AlignVal)
643 AlignVal = getContext().getTypeAlignInChars(Ty).getQuantity();
645 // The glvalue must be suitably aligned.
647 (!PtrToAlloca || PtrToAlloca->getAlignment() < AlignVal)) {
649 Builder.CreateAnd(Builder.CreatePtrToInt(Ptr, IntPtrTy),
650 llvm::ConstantInt::get(IntPtrTy, AlignVal - 1));
651 llvm::Value *Aligned =
652 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0));
653 Checks.push_back(std::make_pair(Aligned, SanitizerKind::Alignment));
657 if (Checks.size() > 0) {
658 // Make sure we're not losing information. Alignment needs to be a power of
660 assert(!AlignVal || (uint64_t)1 << llvm::Log2_64(AlignVal) == AlignVal);
661 llvm::Constant *StaticData[] = {
662 EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(Ty),
663 llvm::ConstantInt::get(Int8Ty, AlignVal ? llvm::Log2_64(AlignVal) : 1),
664 llvm::ConstantInt::get(Int8Ty, TCK)};
665 EmitCheck(Checks, SanitizerHandler::TypeMismatch, StaticData, Ptr);
668 // If possible, check that the vptr indicates that there is a subobject of
669 // type Ty at offset zero within this object.
671 // C++11 [basic.life]p5,6:
672 // [For storage which does not refer to an object within its lifetime]
673 // The program has undefined behavior if:
674 // -- the [pointer or glvalue] is used to access a non-static data member
675 // or call a non-static member function
676 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
677 if (SanOpts.has(SanitizerKind::Vptr) &&
678 !SkippedChecks.has(SanitizerKind::Vptr) &&
679 (TCK == TCK_MemberAccess || TCK == TCK_MemberCall ||
680 TCK == TCK_DowncastPointer || TCK == TCK_DowncastReference ||
681 TCK == TCK_UpcastToVirtualBase) &&
682 RD && RD->hasDefinition() && RD->isDynamicClass()) {
683 // Compute a hash of the mangled name of the type.
685 // FIXME: This is not guaranteed to be deterministic! Move to a
686 // fingerprinting mechanism once LLVM provides one. For the time
687 // being the implementation happens to be deterministic.
688 SmallString<64> MangledName;
689 llvm::raw_svector_ostream Out(MangledName);
690 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(),
693 // Blacklist based on the mangled type.
694 if (!CGM.getContext().getSanitizerBlacklist().isBlacklistedType(
696 llvm::hash_code TypeHash = hash_value(Out.str());
698 // Load the vptr, and compute hash_16_bytes(TypeHash, vptr).
699 llvm::Value *Low = llvm::ConstantInt::get(Int64Ty, TypeHash);
700 llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0);
701 Address VPtrAddr(Builder.CreateBitCast(Ptr, VPtrTy), getPointerAlign());
702 llvm::Value *VPtrVal = Builder.CreateLoad(VPtrAddr);
703 llvm::Value *High = Builder.CreateZExt(VPtrVal, Int64Ty);
705 llvm::Value *Hash = emitHash16Bytes(Builder, Low, High);
706 Hash = Builder.CreateTrunc(Hash, IntPtrTy);
708 // Look the hash up in our cache.
709 const int CacheSize = 128;
710 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize);
711 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable,
712 "__ubsan_vptr_type_cache");
713 llvm::Value *Slot = Builder.CreateAnd(Hash,
714 llvm::ConstantInt::get(IntPtrTy,
716 llvm::Value *Indices[] = { Builder.getInt32(0), Slot };
717 llvm::Value *CacheVal =
718 Builder.CreateAlignedLoad(Builder.CreateInBoundsGEP(Cache, Indices),
721 // If the hash isn't in the cache, call a runtime handler to perform the
722 // hard work of checking whether the vptr is for an object of the right
723 // type. This will either fill in the cache and return, or produce a
725 llvm::Value *EqualHash = Builder.CreateICmpEQ(CacheVal, Hash);
726 llvm::Constant *StaticData[] = {
727 EmitCheckSourceLocation(Loc),
728 EmitCheckTypeDescriptor(Ty),
729 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()),
730 llvm::ConstantInt::get(Int8Ty, TCK)
732 llvm::Value *DynamicData[] = { Ptr, Hash };
733 EmitCheck(std::make_pair(EqualHash, SanitizerKind::Vptr),
734 SanitizerHandler::DynamicTypeCacheMiss, StaticData,
740 Builder.CreateBr(Done);
745 /// Determine whether this expression refers to a flexible array member in a
746 /// struct. We disable array bounds checks for such members.
747 static bool isFlexibleArrayMemberExpr(const Expr *E) {
748 // For compatibility with existing code, we treat arrays of length 0 or
749 // 1 as flexible array members.
750 const ArrayType *AT = E->getType()->castAsArrayTypeUnsafe();
751 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT)) {
752 if (CAT->getSize().ugt(1))
754 } else if (!isa<IncompleteArrayType>(AT))
757 E = E->IgnoreParens();
759 // A flexible array member must be the last member in the class.
760 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
761 // FIXME: If the base type of the member expr is not FD->getParent(),
762 // this should not be treated as a flexible array member access.
763 if (const auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
764 RecordDecl::field_iterator FI(
765 DeclContext::decl_iterator(const_cast<FieldDecl *>(FD)));
766 return ++FI == FD->getParent()->field_end();
768 } else if (const auto *IRE = dyn_cast<ObjCIvarRefExpr>(E)) {
769 return IRE->getDecl()->getNextIvar() == nullptr;
775 /// If Base is known to point to the start of an array, return the length of
776 /// that array. Return 0 if the length cannot be determined.
777 static llvm::Value *getArrayIndexingBound(
778 CodeGenFunction &CGF, const Expr *Base, QualType &IndexedType) {
779 // For the vector indexing extension, the bound is the number of elements.
780 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) {
781 IndexedType = Base->getType();
782 return CGF.Builder.getInt32(VT->getNumElements());
785 Base = Base->IgnoreParens();
787 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
788 if (CE->getCastKind() == CK_ArrayToPointerDecay &&
789 !isFlexibleArrayMemberExpr(CE->getSubExpr())) {
790 IndexedType = CE->getSubExpr()->getType();
791 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe();
792 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT))
793 return CGF.Builder.getInt(CAT->getSize());
794 else if (const auto *VAT = dyn_cast<VariableArrayType>(AT))
795 return CGF.getVLASize(VAT).first;
802 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base,
803 llvm::Value *Index, QualType IndexType,
805 assert(SanOpts.has(SanitizerKind::ArrayBounds) &&
806 "should not be called unless adding bounds checks");
807 SanitizerScope SanScope(this);
809 QualType IndexedType;
810 llvm::Value *Bound = getArrayIndexingBound(*this, Base, IndexedType);
814 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType();
815 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned);
816 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false);
818 llvm::Constant *StaticData[] = {
819 EmitCheckSourceLocation(E->getExprLoc()),
820 EmitCheckTypeDescriptor(IndexedType),
821 EmitCheckTypeDescriptor(IndexType)
823 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal)
824 : Builder.CreateICmpULE(IndexVal, BoundVal);
825 EmitCheck(std::make_pair(Check, SanitizerKind::ArrayBounds),
826 SanitizerHandler::OutOfBounds, StaticData, Index);
830 CodeGenFunction::ComplexPairTy CodeGenFunction::
831 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
832 bool isInc, bool isPre) {
833 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc());
835 llvm::Value *NextVal;
836 if (isa<llvm::IntegerType>(InVal.first->getType())) {
837 uint64_t AmountVal = isInc ? 1 : -1;
838 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
840 // Add the inc/dec to the real part.
841 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
843 QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
844 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
847 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
849 // Add the inc/dec to the real part.
850 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
853 ComplexPairTy IncVal(NextVal, InVal.second);
855 // Store the updated result through the lvalue.
856 EmitStoreOfComplex(IncVal, LV, /*init*/ false);
858 // If this is a postinc, return the value read from memory, otherwise use the
860 return isPre ? IncVal : InVal;
863 void CodeGenModule::EmitExplicitCastExprType(const ExplicitCastExpr *E,
864 CodeGenFunction *CGF) {
865 // Bind VLAs in the cast type.
866 if (CGF && E->getType()->isVariablyModifiedType())
867 CGF->EmitVariablyModifiedType(E->getType());
869 if (CGDebugInfo *DI = getModuleDebugInfo())
870 DI->EmitExplicitCastType(E->getType());
873 //===----------------------------------------------------------------------===//
874 // LValue Expression Emission
875 //===----------------------------------------------------------------------===//
877 /// EmitPointerWithAlignment - Given an expression of pointer type, try to
878 /// derive a more accurate bound on the alignment of the pointer.
879 Address CodeGenFunction::EmitPointerWithAlignment(const Expr *E,
880 LValueBaseInfo *BaseInfo) {
881 // We allow this with ObjC object pointers because of fragile ABIs.
882 assert(E->getType()->isPointerType() ||
883 E->getType()->isObjCObjectPointerType());
884 E = E->IgnoreParens();
887 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
888 if (const auto *ECE = dyn_cast<ExplicitCastExpr>(CE))
889 CGM.EmitExplicitCastExprType(ECE, this);
891 switch (CE->getCastKind()) {
892 // Non-converting casts (but not C's implicit conversion from void*).
895 if (auto PtrTy = CE->getSubExpr()->getType()->getAs<PointerType>()) {
896 if (PtrTy->getPointeeType()->isVoidType())
899 LValueBaseInfo InnerInfo;
900 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(), &InnerInfo);
901 if (BaseInfo) *BaseInfo = InnerInfo;
903 // If this is an explicit bitcast, and the source l-value is
904 // opaque, honor the alignment of the casted-to type.
905 if (isa<ExplicitCastExpr>(CE) &&
906 InnerInfo.getAlignmentSource() != AlignmentSource::Decl) {
907 LValueBaseInfo ExpInfo;
908 CharUnits Align = getNaturalPointeeTypeAlignment(E->getType(),
911 BaseInfo->mergeForCast(ExpInfo);
912 Addr = Address(Addr.getPointer(), Align);
915 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast) &&
916 CE->getCastKind() == CK_BitCast) {
917 if (auto PT = E->getType()->getAs<PointerType>())
918 EmitVTablePtrCheckForCast(PT->getPointeeType(), Addr.getPointer(),
920 CodeGenFunction::CFITCK_UnrelatedCast,
924 return Builder.CreateBitCast(Addr, ConvertType(E->getType()));
928 // Array-to-pointer decay.
929 case CK_ArrayToPointerDecay:
930 return EmitArrayToPointerDecay(CE->getSubExpr(), BaseInfo);
932 // Derived-to-base conversions.
933 case CK_UncheckedDerivedToBase:
934 case CK_DerivedToBase: {
935 Address Addr = EmitPointerWithAlignment(CE->getSubExpr(), BaseInfo);
936 auto Derived = CE->getSubExpr()->getType()->getPointeeCXXRecordDecl();
937 return GetAddressOfBaseClass(Addr, Derived,
938 CE->path_begin(), CE->path_end(),
939 ShouldNullCheckClassCastValue(CE),
943 // TODO: Is there any reason to treat base-to-derived conversions
951 if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
952 if (UO->getOpcode() == UO_AddrOf) {
953 LValue LV = EmitLValue(UO->getSubExpr());
954 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
955 return LV.getAddress();
959 // TODO: conditional operators, comma.
961 // Otherwise, use the alignment of the type.
962 CharUnits Align = getNaturalPointeeTypeAlignment(E->getType(), BaseInfo);
963 return Address(EmitScalarExpr(E), Align);
966 RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
967 if (Ty->isVoidType())
968 return RValue::get(nullptr);
970 switch (getEvaluationKind(Ty)) {
973 ConvertType(Ty->castAs<ComplexType>()->getElementType());
974 llvm::Value *U = llvm::UndefValue::get(EltTy);
975 return RValue::getComplex(std::make_pair(U, U));
978 // If this is a use of an undefined aggregate type, the aggregate must have an
979 // identifiable address. Just because the contents of the value are undefined
980 // doesn't mean that the address can't be taken and compared.
981 case TEK_Aggregate: {
982 Address DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
983 return RValue::getAggregate(DestPtr);
987 return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
989 llvm_unreachable("bad evaluation kind");
992 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
994 ErrorUnsupported(E, Name);
995 return GetUndefRValue(E->getType());
998 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
1000 ErrorUnsupported(E, Name);
1001 llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
1002 return MakeAddrLValue(Address(llvm::UndefValue::get(Ty), CharUnits::One()),
1006 bool CodeGenFunction::IsWrappedCXXThis(const Expr *Obj) {
1007 const Expr *Base = Obj;
1008 while (!isa<CXXThisExpr>(Base)) {
1009 // The result of a dynamic_cast can be null.
1010 if (isa<CXXDynamicCastExpr>(Base))
1013 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
1014 Base = CE->getSubExpr();
1015 } else if (const auto *PE = dyn_cast<ParenExpr>(Base)) {
1016 Base = PE->getSubExpr();
1017 } else if (const auto *UO = dyn_cast<UnaryOperator>(Base)) {
1018 if (UO->getOpcode() == UO_Extension)
1019 Base = UO->getSubExpr();
1029 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) {
1031 if (SanOpts.has(SanitizerKind::ArrayBounds) && isa<ArraySubscriptExpr>(E))
1032 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true);
1035 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple()) {
1036 SanitizerSet SkippedChecks;
1037 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
1038 bool IsBaseCXXThis = IsWrappedCXXThis(ME->getBase());
1040 SkippedChecks.set(SanitizerKind::Alignment, true);
1041 if (IsBaseCXXThis || isa<DeclRefExpr>(ME->getBase()))
1042 SkippedChecks.set(SanitizerKind::Null, true);
1044 EmitTypeCheck(TCK, E->getExprLoc(), LV.getPointer(),
1045 E->getType(), LV.getAlignment(), SkippedChecks);
1050 /// EmitLValue - Emit code to compute a designator that specifies the location
1051 /// of the expression.
1053 /// This can return one of two things: a simple address or a bitfield reference.
1054 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be
1055 /// an LLVM pointer type.
1057 /// If this returns a bitfield reference, nothing about the pointee type of the
1058 /// LLVM value is known: For example, it may not be a pointer to an integer.
1060 /// If this returns a normal address, and if the lvalue's C type is fixed size,
1061 /// this method guarantees that the returned pointer type will point to an LLVM
1062 /// type of the same size of the lvalue's type. If the lvalue has a variable
1063 /// length type, this is not possible.
1065 LValue CodeGenFunction::EmitLValue(const Expr *E) {
1066 ApplyDebugLocation DL(*this, E);
1067 switch (E->getStmtClass()) {
1068 default: return EmitUnsupportedLValue(E, "l-value expression");
1070 case Expr::ObjCPropertyRefExprClass:
1071 llvm_unreachable("cannot emit a property reference directly");
1073 case Expr::ObjCSelectorExprClass:
1074 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
1075 case Expr::ObjCIsaExprClass:
1076 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
1077 case Expr::BinaryOperatorClass:
1078 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
1079 case Expr::CompoundAssignOperatorClass: {
1080 QualType Ty = E->getType();
1081 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1082 Ty = AT->getValueType();
1083 if (!Ty->isAnyComplexType())
1084 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1085 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
1087 case Expr::CallExprClass:
1088 case Expr::CXXMemberCallExprClass:
1089 case Expr::CXXOperatorCallExprClass:
1090 case Expr::UserDefinedLiteralClass:
1091 return EmitCallExprLValue(cast<CallExpr>(E));
1092 case Expr::VAArgExprClass:
1093 return EmitVAArgExprLValue(cast<VAArgExpr>(E));
1094 case Expr::DeclRefExprClass:
1095 return EmitDeclRefLValue(cast<DeclRefExpr>(E));
1096 case Expr::ParenExprClass:
1097 return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
1098 case Expr::GenericSelectionExprClass:
1099 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr());
1100 case Expr::PredefinedExprClass:
1101 return EmitPredefinedLValue(cast<PredefinedExpr>(E));
1102 case Expr::StringLiteralClass:
1103 return EmitStringLiteralLValue(cast<StringLiteral>(E));
1104 case Expr::ObjCEncodeExprClass:
1105 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
1106 case Expr::PseudoObjectExprClass:
1107 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E));
1108 case Expr::InitListExprClass:
1109 return EmitInitListLValue(cast<InitListExpr>(E));
1110 case Expr::CXXTemporaryObjectExprClass:
1111 case Expr::CXXConstructExprClass:
1112 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
1113 case Expr::CXXBindTemporaryExprClass:
1114 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
1115 case Expr::CXXUuidofExprClass:
1116 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E));
1117 case Expr::LambdaExprClass:
1118 return EmitLambdaLValue(cast<LambdaExpr>(E));
1120 case Expr::ExprWithCleanupsClass: {
1121 const auto *cleanups = cast<ExprWithCleanups>(E);
1122 enterFullExpression(cleanups);
1123 RunCleanupsScope Scope(*this);
1124 LValue LV = EmitLValue(cleanups->getSubExpr());
1125 if (LV.isSimple()) {
1126 // Defend against branches out of gnu statement expressions surrounded by
1128 llvm::Value *V = LV.getPointer();
1129 Scope.ForceCleanup({&V});
1130 return LValue::MakeAddr(Address(V, LV.getAlignment()), LV.getType(),
1131 getContext(), LV.getBaseInfo(),
1134 // FIXME: Is it possible to create an ExprWithCleanups that produces a
1135 // bitfield lvalue or some other non-simple lvalue?
1139 case Expr::CXXDefaultArgExprClass:
1140 return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr());
1141 case Expr::CXXDefaultInitExprClass: {
1142 CXXDefaultInitExprScope Scope(*this);
1143 return EmitLValue(cast<CXXDefaultInitExpr>(E)->getExpr());
1145 case Expr::CXXTypeidExprClass:
1146 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
1148 case Expr::ObjCMessageExprClass:
1149 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
1150 case Expr::ObjCIvarRefExprClass:
1151 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
1152 case Expr::StmtExprClass:
1153 return EmitStmtExprLValue(cast<StmtExpr>(E));
1154 case Expr::UnaryOperatorClass:
1155 return EmitUnaryOpLValue(cast<UnaryOperator>(E));
1156 case Expr::ArraySubscriptExprClass:
1157 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
1158 case Expr::OMPArraySectionExprClass:
1159 return EmitOMPArraySectionExpr(cast<OMPArraySectionExpr>(E));
1160 case Expr::ExtVectorElementExprClass:
1161 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
1162 case Expr::MemberExprClass:
1163 return EmitMemberExpr(cast<MemberExpr>(E));
1164 case Expr::CompoundLiteralExprClass:
1165 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
1166 case Expr::ConditionalOperatorClass:
1167 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
1168 case Expr::BinaryConditionalOperatorClass:
1169 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
1170 case Expr::ChooseExprClass:
1171 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr());
1172 case Expr::OpaqueValueExprClass:
1173 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
1174 case Expr::SubstNonTypeTemplateParmExprClass:
1175 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement());
1176 case Expr::ImplicitCastExprClass:
1177 case Expr::CStyleCastExprClass:
1178 case Expr::CXXFunctionalCastExprClass:
1179 case Expr::CXXStaticCastExprClass:
1180 case Expr::CXXDynamicCastExprClass:
1181 case Expr::CXXReinterpretCastExprClass:
1182 case Expr::CXXConstCastExprClass:
1183 case Expr::ObjCBridgedCastExprClass:
1184 return EmitCastLValue(cast<CastExpr>(E));
1186 case Expr::MaterializeTemporaryExprClass:
1187 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E));
1189 case Expr::CoawaitExprClass:
1190 return EmitCoawaitLValue(cast<CoawaitExpr>(E));
1191 case Expr::CoyieldExprClass:
1192 return EmitCoyieldLValue(cast<CoyieldExpr>(E));
1196 /// Given an object of the given canonical type, can we safely copy a
1197 /// value out of it based on its initializer?
1198 static bool isConstantEmittableObjectType(QualType type) {
1199 assert(type.isCanonical());
1200 assert(!type->isReferenceType());
1202 // Must be const-qualified but non-volatile.
1203 Qualifiers qs = type.getLocalQualifiers();
1204 if (!qs.hasConst() || qs.hasVolatile()) return false;
1206 // Otherwise, all object types satisfy this except C++ classes with
1207 // mutable subobjects or non-trivial copy/destroy behavior.
1208 if (const auto *RT = dyn_cast<RecordType>(type))
1209 if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
1210 if (RD->hasMutableFields() || !RD->isTrivial())
1216 /// Can we constant-emit a load of a reference to a variable of the
1217 /// given type? This is different from predicates like
1218 /// Decl::isUsableInConstantExpressions because we do want it to apply
1219 /// in situations that don't necessarily satisfy the language's rules
1220 /// for this (e.g. C++'s ODR-use rules). For example, we want to able
1221 /// to do this with const float variables even if those variables
1222 /// aren't marked 'constexpr'.
1223 enum ConstantEmissionKind {
1225 CEK_AsReferenceOnly,
1226 CEK_AsValueOrReference,
1229 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) {
1230 type = type.getCanonicalType();
1231 if (const auto *ref = dyn_cast<ReferenceType>(type)) {
1232 if (isConstantEmittableObjectType(ref->getPointeeType()))
1233 return CEK_AsValueOrReference;
1234 return CEK_AsReferenceOnly;
1236 if (isConstantEmittableObjectType(type))
1237 return CEK_AsValueOnly;
1241 /// Try to emit a reference to the given value without producing it as
1242 /// an l-value. This is actually more than an optimization: we can't
1243 /// produce an l-value for variables that we never actually captured
1244 /// in a block or lambda, which means const int variables or constexpr
1245 /// literals or similar.
1246 CodeGenFunction::ConstantEmission
1247 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) {
1248 ValueDecl *value = refExpr->getDecl();
1250 // The value needs to be an enum constant or a constant variable.
1251 ConstantEmissionKind CEK;
1252 if (isa<ParmVarDecl>(value)) {
1254 } else if (auto *var = dyn_cast<VarDecl>(value)) {
1255 CEK = checkVarTypeForConstantEmission(var->getType());
1256 } else if (isa<EnumConstantDecl>(value)) {
1257 CEK = CEK_AsValueOnly;
1261 if (CEK == CEK_None) return ConstantEmission();
1263 Expr::EvalResult result;
1264 bool resultIsReference;
1265 QualType resultType;
1267 // It's best to evaluate all the way as an r-value if that's permitted.
1268 if (CEK != CEK_AsReferenceOnly &&
1269 refExpr->EvaluateAsRValue(result, getContext())) {
1270 resultIsReference = false;
1271 resultType = refExpr->getType();
1273 // Otherwise, try to evaluate as an l-value.
1274 } else if (CEK != CEK_AsValueOnly &&
1275 refExpr->EvaluateAsLValue(result, getContext())) {
1276 resultIsReference = true;
1277 resultType = value->getType();
1281 return ConstantEmission();
1284 // In any case, if the initializer has side-effects, abandon ship.
1285 if (result.HasSideEffects)
1286 return ConstantEmission();
1288 // Emit as a constant.
1289 llvm::Constant *C = CGM.EmitConstantValue(result.Val, resultType, this);
1291 // Make sure we emit a debug reference to the global variable.
1292 // This should probably fire even for
1293 if (isa<VarDecl>(value)) {
1294 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value)))
1295 EmitDeclRefExprDbgValue(refExpr, result.Val);
1297 assert(isa<EnumConstantDecl>(value));
1298 EmitDeclRefExprDbgValue(refExpr, result.Val);
1301 // If we emitted a reference constant, we need to dereference that.
1302 if (resultIsReference)
1303 return ConstantEmission::forReference(C);
1305 return ConstantEmission::forValue(C);
1308 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue,
1309 SourceLocation Loc) {
1310 return EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatile(),
1311 lvalue.getType(), Loc, lvalue.getBaseInfo(),
1312 lvalue.getTBAAInfo(),
1313 lvalue.getTBAABaseType(), lvalue.getTBAAOffset(),
1314 lvalue.isNontemporal());
1317 static bool hasBooleanRepresentation(QualType Ty) {
1318 if (Ty->isBooleanType())
1321 if (const EnumType *ET = Ty->getAs<EnumType>())
1322 return ET->getDecl()->getIntegerType()->isBooleanType();
1324 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1325 return hasBooleanRepresentation(AT->getValueType());
1330 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty,
1331 llvm::APInt &Min, llvm::APInt &End,
1332 bool StrictEnums, bool IsBool) {
1333 const EnumType *ET = Ty->getAs<EnumType>();
1334 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums &&
1335 ET && !ET->getDecl()->isFixed();
1336 if (!IsBool && !IsRegularCPlusPlusEnum)
1340 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0);
1341 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2);
1343 const EnumDecl *ED = ET->getDecl();
1344 llvm::Type *LTy = CGF.ConvertTypeForMem(ED->getIntegerType());
1345 unsigned Bitwidth = LTy->getScalarSizeInBits();
1346 unsigned NumNegativeBits = ED->getNumNegativeBits();
1347 unsigned NumPositiveBits = ED->getNumPositiveBits();
1349 if (NumNegativeBits) {
1350 unsigned NumBits = std::max(NumNegativeBits, NumPositiveBits + 1);
1351 assert(NumBits <= Bitwidth);
1352 End = llvm::APInt(Bitwidth, 1) << (NumBits - 1);
1355 assert(NumPositiveBits <= Bitwidth);
1356 End = llvm::APInt(Bitwidth, 1) << NumPositiveBits;
1357 Min = llvm::APInt(Bitwidth, 0);
1363 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) {
1364 llvm::APInt Min, End;
1365 if (!getRangeForType(*this, Ty, Min, End, CGM.getCodeGenOpts().StrictEnums,
1366 hasBooleanRepresentation(Ty)))
1369 llvm::MDBuilder MDHelper(getLLVMContext());
1370 return MDHelper.createRange(Min, End);
1373 bool CodeGenFunction::EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
1374 SourceLocation Loc) {
1375 bool HasBoolCheck = SanOpts.has(SanitizerKind::Bool);
1376 bool HasEnumCheck = SanOpts.has(SanitizerKind::Enum);
1377 if (!HasBoolCheck && !HasEnumCheck)
1380 bool IsBool = hasBooleanRepresentation(Ty) ||
1381 NSAPI(CGM.getContext()).isObjCBOOLType(Ty);
1382 bool NeedsBoolCheck = HasBoolCheck && IsBool;
1383 bool NeedsEnumCheck = HasEnumCheck && Ty->getAs<EnumType>();
1384 if (!NeedsBoolCheck && !NeedsEnumCheck)
1387 // Single-bit booleans don't need to be checked. Special-case this to avoid
1388 // a bit width mismatch when handling bitfield values. This is handled by
1389 // EmitFromMemory for the non-bitfield case.
1391 cast<llvm::IntegerType>(Value->getType())->getBitWidth() == 1)
1394 llvm::APInt Min, End;
1395 if (!getRangeForType(*this, Ty, Min, End, /*StrictEnums=*/true, IsBool))
1398 SanitizerScope SanScope(this);
1402 Check = Builder.CreateICmpULE(
1403 Value, llvm::ConstantInt::get(getLLVMContext(), End));
1405 llvm::Value *Upper = Builder.CreateICmpSLE(
1406 Value, llvm::ConstantInt::get(getLLVMContext(), End));
1407 llvm::Value *Lower = Builder.CreateICmpSGE(
1408 Value, llvm::ConstantInt::get(getLLVMContext(), Min));
1409 Check = Builder.CreateAnd(Upper, Lower);
1411 llvm::Constant *StaticArgs[] = {EmitCheckSourceLocation(Loc),
1412 EmitCheckTypeDescriptor(Ty)};
1413 SanitizerMask Kind =
1414 NeedsEnumCheck ? SanitizerKind::Enum : SanitizerKind::Bool;
1415 EmitCheck(std::make_pair(Check, Kind), SanitizerHandler::LoadInvalidValue,
1416 StaticArgs, EmitCheckValue(Value));
1420 llvm::Value *CodeGenFunction::EmitLoadOfScalar(Address Addr, bool Volatile,
1423 LValueBaseInfo BaseInfo,
1424 llvm::MDNode *TBAAInfo,
1425 QualType TBAABaseType,
1426 uint64_t TBAAOffset,
1427 bool isNontemporal) {
1428 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1429 // For better performance, handle vector loads differently.
1430 if (Ty->isVectorType()) {
1431 const llvm::Type *EltTy = Addr.getElementType();
1433 const auto *VTy = cast<llvm::VectorType>(EltTy);
1435 // Handle vectors of size 3 like size 4 for better performance.
1436 if (VTy->getNumElements() == 3) {
1438 // Bitcast to vec4 type.
1439 llvm::VectorType *vec4Ty =
1440 llvm::VectorType::get(VTy->getElementType(), 4);
1441 Address Cast = Builder.CreateElementBitCast(Addr, vec4Ty, "castToVec4");
1443 llvm::Value *V = Builder.CreateLoad(Cast, Volatile, "loadVec4");
1445 // Shuffle vector to get vec3.
1446 V = Builder.CreateShuffleVector(V, llvm::UndefValue::get(vec4Ty),
1447 {0, 1, 2}, "extractVec");
1448 return EmitFromMemory(V, Ty);
1453 // Atomic operations have to be done on integral types.
1454 LValue AtomicLValue =
1455 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1456 if (Ty->isAtomicType() || LValueIsSuitableForInlineAtomic(AtomicLValue)) {
1457 return EmitAtomicLoad(AtomicLValue, Loc).getScalarVal();
1460 llvm::LoadInst *Load = Builder.CreateLoad(Addr, Volatile);
1461 if (isNontemporal) {
1462 llvm::MDNode *Node = llvm::MDNode::get(
1463 Load->getContext(), llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1464 Load->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1467 bool MayAlias = BaseInfo.getMayAlias();
1468 llvm::MDNode *TBAA = MayAlias
1469 ? CGM.getTBAAInfo(getContext().CharTy)
1470 : CGM.getTBAAStructTagInfo(TBAABaseType, TBAAInfo, TBAAOffset);
1472 CGM.DecorateInstructionWithTBAA(Load, TBAA, MayAlias);
1475 if (EmitScalarRangeCheck(Load, Ty, Loc)) {
1476 // In order to prevent the optimizer from throwing away the check, don't
1477 // attach range metadata to the load.
1478 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0)
1479 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty))
1480 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo);
1482 return EmitFromMemory(Load, Ty);
1485 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
1486 // Bool has a different representation in memory than in registers.
1487 if (hasBooleanRepresentation(Ty)) {
1488 // This should really always be an i1, but sometimes it's already
1489 // an i8, and it's awkward to track those cases down.
1490 if (Value->getType()->isIntegerTy(1))
1491 return Builder.CreateZExt(Value, ConvertTypeForMem(Ty), "frombool");
1492 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1493 "wrong value rep of bool");
1499 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
1500 // Bool has a different representation in memory than in registers.
1501 if (hasBooleanRepresentation(Ty)) {
1502 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1503 "wrong value rep of bool");
1504 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool");
1510 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, Address Addr,
1511 bool Volatile, QualType Ty,
1512 LValueBaseInfo BaseInfo,
1513 llvm::MDNode *TBAAInfo,
1514 bool isInit, QualType TBAABaseType,
1515 uint64_t TBAAOffset,
1516 bool isNontemporal) {
1518 if (!CGM.getCodeGenOpts().PreserveVec3Type) {
1519 // Handle vectors differently to get better performance.
1520 if (Ty->isVectorType()) {
1521 llvm::Type *SrcTy = Value->getType();
1522 auto *VecTy = dyn_cast<llvm::VectorType>(SrcTy);
1523 // Handle vec3 special.
1524 if (VecTy && VecTy->getNumElements() == 3) {
1525 // Our source is a vec3, do a shuffle vector to make it a vec4.
1526 llvm::Constant *Mask[] = {Builder.getInt32(0), Builder.getInt32(1),
1527 Builder.getInt32(2),
1528 llvm::UndefValue::get(Builder.getInt32Ty())};
1529 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1530 Value = Builder.CreateShuffleVector(Value, llvm::UndefValue::get(VecTy),
1531 MaskV, "extractVec");
1532 SrcTy = llvm::VectorType::get(VecTy->getElementType(), 4);
1534 if (Addr.getElementType() != SrcTy) {
1535 Addr = Builder.CreateElementBitCast(Addr, SrcTy, "storetmp");
1540 Value = EmitToMemory(Value, Ty);
1542 LValue AtomicLValue =
1543 LValue::MakeAddr(Addr, Ty, getContext(), BaseInfo, TBAAInfo);
1544 if (Ty->isAtomicType() ||
1545 (!isInit && LValueIsSuitableForInlineAtomic(AtomicLValue))) {
1546 EmitAtomicStore(RValue::get(Value), AtomicLValue, isInit);
1550 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
1551 if (isNontemporal) {
1552 llvm::MDNode *Node =
1553 llvm::MDNode::get(Store->getContext(),
1554 llvm::ConstantAsMetadata::get(Builder.getInt32(1)));
1555 Store->setMetadata(CGM.getModule().getMDKindID("nontemporal"), Node);
1558 bool MayAlias = BaseInfo.getMayAlias();
1559 llvm::MDNode *TBAA = MayAlias
1560 ? CGM.getTBAAInfo(getContext().CharTy)
1561 : CGM.getTBAAStructTagInfo(TBAABaseType, TBAAInfo, TBAAOffset);
1563 CGM.DecorateInstructionWithTBAA(Store, TBAA, MayAlias);
1567 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue,
1569 EmitStoreOfScalar(value, lvalue.getAddress(), lvalue.isVolatile(),
1570 lvalue.getType(), lvalue.getBaseInfo(),
1571 lvalue.getTBAAInfo(), isInit, lvalue.getTBAABaseType(),
1572 lvalue.getTBAAOffset(), lvalue.isNontemporal());
1575 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
1576 /// method emits the address of the lvalue, then loads the result as an rvalue,
1577 /// returning the rvalue.
1578 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
1579 if (LV.isObjCWeak()) {
1580 // load of a __weak object.
1581 Address AddrWeakObj = LV.getAddress();
1582 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
1585 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
1586 // In MRC mode, we do a load+autorelease.
1587 if (!getLangOpts().ObjCAutoRefCount) {
1588 return RValue::get(EmitARCLoadWeak(LV.getAddress()));
1591 // In ARC mode, we load retained and then consume the value.
1592 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress());
1593 Object = EmitObjCConsumeObject(LV.getType(), Object);
1594 return RValue::get(Object);
1597 if (LV.isSimple()) {
1598 assert(!LV.getType()->isFunctionType());
1600 // Everything needs a load.
1601 return RValue::get(EmitLoadOfScalar(LV, Loc));
1604 if (LV.isVectorElt()) {
1605 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddress(),
1606 LV.isVolatileQualified());
1607 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(),
1611 // If this is a reference to a subset of the elements of a vector, either
1612 // shuffle the input or extract/insert them as appropriate.
1613 if (LV.isExtVectorElt())
1614 return EmitLoadOfExtVectorElementLValue(LV);
1616 // Global Register variables always invoke intrinsics
1617 if (LV.isGlobalReg())
1618 return EmitLoadOfGlobalRegLValue(LV);
1620 assert(LV.isBitField() && "Unknown LValue type!");
1621 return EmitLoadOfBitfieldLValue(LV, Loc);
1624 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV,
1625 SourceLocation Loc) {
1626 const CGBitFieldInfo &Info = LV.getBitFieldInfo();
1628 // Get the output type.
1629 llvm::Type *ResLTy = ConvertType(LV.getType());
1631 Address Ptr = LV.getBitFieldAddress();
1632 llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(), "bf.load");
1634 if (Info.IsSigned) {
1635 assert(static_cast<unsigned>(Info.Offset + Info.Size) <= Info.StorageSize);
1636 unsigned HighBits = Info.StorageSize - Info.Offset - Info.Size;
1638 Val = Builder.CreateShl(Val, HighBits, "bf.shl");
1639 if (Info.Offset + HighBits)
1640 Val = Builder.CreateAShr(Val, Info.Offset + HighBits, "bf.ashr");
1643 Val = Builder.CreateLShr(Val, Info.Offset, "bf.lshr");
1644 if (static_cast<unsigned>(Info.Offset) + Info.Size < Info.StorageSize)
1645 Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(Info.StorageSize,
1649 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast");
1650 EmitScalarRangeCheck(Val, LV.getType(), Loc);
1651 return RValue::get(Val);
1654 // If this is a reference to a subset of the elements of a vector, create an
1655 // appropriate shufflevector.
1656 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) {
1657 llvm::Value *Vec = Builder.CreateLoad(LV.getExtVectorAddress(),
1658 LV.isVolatileQualified());
1660 const llvm::Constant *Elts = LV.getExtVectorElts();
1662 // If the result of the expression is a non-vector type, we must be extracting
1663 // a single element. Just codegen as an extractelement.
1664 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1666 unsigned InIdx = getAccessedFieldNo(0, Elts);
1667 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1668 return RValue::get(Builder.CreateExtractElement(Vec, Elt));
1671 // Always use shuffle vector to try to retain the original program structure
1672 unsigned NumResultElts = ExprVT->getNumElements();
1674 SmallVector<llvm::Constant*, 4> Mask;
1675 for (unsigned i = 0; i != NumResultElts; ++i)
1676 Mask.push_back(Builder.getInt32(getAccessedFieldNo(i, Elts)));
1678 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1679 Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()),
1681 return RValue::get(Vec);
1684 /// @brief Generates lvalue for partial ext_vector access.
1685 Address CodeGenFunction::EmitExtVectorElementLValue(LValue LV) {
1686 Address VectorAddress = LV.getExtVectorAddress();
1687 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1688 QualType EQT = ExprVT->getElementType();
1689 llvm::Type *VectorElementTy = CGM.getTypes().ConvertType(EQT);
1691 Address CastToPointerElement =
1692 Builder.CreateElementBitCast(VectorAddress, VectorElementTy,
1693 "conv.ptr.element");
1695 const llvm::Constant *Elts = LV.getExtVectorElts();
1696 unsigned ix = getAccessedFieldNo(0, Elts);
1698 Address VectorBasePtrPlusIx =
1699 Builder.CreateConstInBoundsGEP(CastToPointerElement, ix,
1700 getContext().getTypeSizeInChars(EQT),
1703 return VectorBasePtrPlusIx;
1706 /// @brief Load of global gamed gegisters are always calls to intrinsics.
1707 RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) {
1708 assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) &&
1709 "Bad type for register variable");
1710 llvm::MDNode *RegName = cast<llvm::MDNode>(
1711 cast<llvm::MetadataAsValue>(LV.getGlobalReg())->getMetadata());
1713 // We accept integer and pointer types only
1714 llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType());
1715 llvm::Type *Ty = OrigTy;
1716 if (OrigTy->isPointerTy())
1717 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
1718 llvm::Type *Types[] = { Ty };
1720 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types);
1721 llvm::Value *Call = Builder.CreateCall(
1722 F, llvm::MetadataAsValue::get(Ty->getContext(), RegName));
1723 if (OrigTy->isPointerTy())
1724 Call = Builder.CreateIntToPtr(Call, OrigTy);
1725 return RValue::get(Call);
1729 /// EmitStoreThroughLValue - Store the specified rvalue into the specified
1730 /// lvalue, where both are guaranteed to the have the same type, and that type
1732 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
1734 if (!Dst.isSimple()) {
1735 if (Dst.isVectorElt()) {
1736 // Read/modify/write the vector, inserting the new element.
1737 llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddress(),
1738 Dst.isVolatileQualified());
1739 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
1740 Dst.getVectorIdx(), "vecins");
1741 Builder.CreateStore(Vec, Dst.getVectorAddress(),
1742 Dst.isVolatileQualified());
1746 // If this is an update of extended vector elements, insert them as
1748 if (Dst.isExtVectorElt())
1749 return EmitStoreThroughExtVectorComponentLValue(Src, Dst);
1751 if (Dst.isGlobalReg())
1752 return EmitStoreThroughGlobalRegLValue(Src, Dst);
1754 assert(Dst.isBitField() && "Unknown LValue type");
1755 return EmitStoreThroughBitfieldLValue(Src, Dst);
1758 // There's special magic for assigning into an ARC-qualified l-value.
1759 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) {
1761 case Qualifiers::OCL_None:
1762 llvm_unreachable("present but none");
1764 case Qualifiers::OCL_ExplicitNone:
1768 case Qualifiers::OCL_Strong:
1770 Src = RValue::get(EmitARCRetain(Dst.getType(), Src.getScalarVal()));
1773 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true);
1776 case Qualifiers::OCL_Weak:
1778 // Initialize and then skip the primitive store.
1779 EmitARCInitWeak(Dst.getAddress(), Src.getScalarVal());
1781 EmitARCStoreWeak(Dst.getAddress(), Src.getScalarVal(), /*ignore*/ true);
1784 case Qualifiers::OCL_Autoreleasing:
1785 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(),
1786 Src.getScalarVal()));
1787 // fall into the normal path
1792 if (Dst.isObjCWeak() && !Dst.isNonGC()) {
1793 // load of a __weak object.
1794 Address LvalueDst = Dst.getAddress();
1795 llvm::Value *src = Src.getScalarVal();
1796 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
1800 if (Dst.isObjCStrong() && !Dst.isNonGC()) {
1801 // load of a __strong object.
1802 Address LvalueDst = Dst.getAddress();
1803 llvm::Value *src = Src.getScalarVal();
1804 if (Dst.isObjCIvar()) {
1805 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
1806 llvm::Type *ResultType = IntPtrTy;
1807 Address dst = EmitPointerWithAlignment(Dst.getBaseIvarExp());
1808 llvm::Value *RHS = dst.getPointer();
1809 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
1811 Builder.CreatePtrToInt(LvalueDst.getPointer(), ResultType,
1812 "sub.ptr.lhs.cast");
1813 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
1814 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
1816 } else if (Dst.isGlobalObjCRef()) {
1817 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
1818 Dst.isThreadLocalRef());
1821 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
1825 assert(Src.isScalar() && "Can't emit an agg store with this method");
1826 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit);
1829 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
1830 llvm::Value **Result) {
1831 const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
1832 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType());
1833 Address Ptr = Dst.getBitFieldAddress();
1835 // Get the source value, truncated to the width of the bit-field.
1836 llvm::Value *SrcVal = Src.getScalarVal();
1838 // Cast the source to the storage type and shift it into place.
1839 SrcVal = Builder.CreateIntCast(SrcVal, Ptr.getElementType(),
1840 /*IsSigned=*/false);
1841 llvm::Value *MaskedVal = SrcVal;
1843 // See if there are other bits in the bitfield's storage we'll need to load
1844 // and mask together with source before storing.
1845 if (Info.StorageSize != Info.Size) {
1846 assert(Info.StorageSize > Info.Size && "Invalid bitfield size.");
1848 Builder.CreateLoad(Ptr, Dst.isVolatileQualified(), "bf.load");
1850 // Mask the source value as needed.
1851 if (!hasBooleanRepresentation(Dst.getType()))
1852 SrcVal = Builder.CreateAnd(SrcVal,
1853 llvm::APInt::getLowBitsSet(Info.StorageSize,
1858 SrcVal = Builder.CreateShl(SrcVal, Info.Offset, "bf.shl");
1860 // Mask out the original value.
1861 Val = Builder.CreateAnd(Val,
1862 ~llvm::APInt::getBitsSet(Info.StorageSize,
1864 Info.Offset + Info.Size),
1867 // Or together the unchanged values and the source value.
1868 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set");
1870 assert(Info.Offset == 0);
1873 // Write the new value back out.
1874 Builder.CreateStore(SrcVal, Ptr, Dst.isVolatileQualified());
1876 // Return the new value of the bit-field, if requested.
1878 llvm::Value *ResultVal = MaskedVal;
1880 // Sign extend the value if needed.
1881 if (Info.IsSigned) {
1882 assert(Info.Size <= Info.StorageSize);
1883 unsigned HighBits = Info.StorageSize - Info.Size;
1885 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl");
1886 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr");
1890 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned,
1892 *Result = EmitFromMemory(ResultVal, Dst.getType());
1896 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
1898 // This access turns into a read/modify/write of the vector. Load the input
1900 llvm::Value *Vec = Builder.CreateLoad(Dst.getExtVectorAddress(),
1901 Dst.isVolatileQualified());
1902 const llvm::Constant *Elts = Dst.getExtVectorElts();
1904 llvm::Value *SrcVal = Src.getScalarVal();
1906 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) {
1907 unsigned NumSrcElts = VTy->getNumElements();
1908 unsigned NumDstElts = Vec->getType()->getVectorNumElements();
1909 if (NumDstElts == NumSrcElts) {
1910 // Use shuffle vector is the src and destination are the same number of
1911 // elements and restore the vector mask since it is on the side it will be
1913 SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
1914 for (unsigned i = 0; i != NumSrcElts; ++i)
1915 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i);
1917 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1918 Vec = Builder.CreateShuffleVector(SrcVal,
1919 llvm::UndefValue::get(Vec->getType()),
1921 } else if (NumDstElts > NumSrcElts) {
1922 // Extended the source vector to the same length and then shuffle it
1923 // into the destination.
1924 // FIXME: since we're shuffling with undef, can we just use the indices
1925 // into that? This could be simpler.
1926 SmallVector<llvm::Constant*, 4> ExtMask;
1927 for (unsigned i = 0; i != NumSrcElts; ++i)
1928 ExtMask.push_back(Builder.getInt32(i));
1929 ExtMask.resize(NumDstElts, llvm::UndefValue::get(Int32Ty));
1930 llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask);
1931 llvm::Value *ExtSrcVal =
1932 Builder.CreateShuffleVector(SrcVal,
1933 llvm::UndefValue::get(SrcVal->getType()),
1936 SmallVector<llvm::Constant*, 4> Mask;
1937 for (unsigned i = 0; i != NumDstElts; ++i)
1938 Mask.push_back(Builder.getInt32(i));
1940 // When the vector size is odd and .odd or .hi is used, the last element
1941 // of the Elts constant array will be one past the size of the vector.
1942 // Ignore the last element here, if it is greater than the mask size.
1943 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size())
1946 // modify when what gets shuffled in
1947 for (unsigned i = 0; i != NumSrcElts; ++i)
1948 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i+NumDstElts);
1949 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1950 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV);
1952 // We should never shorten the vector
1953 llvm_unreachable("unexpected shorten vector length");
1956 // If the Src is a scalar (not a vector) it must be updating one element.
1957 unsigned InIdx = getAccessedFieldNo(0, Elts);
1958 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1959 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt);
1962 Builder.CreateStore(Vec, Dst.getExtVectorAddress(),
1963 Dst.isVolatileQualified());
1966 /// @brief Store of global named registers are always calls to intrinsics.
1967 void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) {
1968 assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) &&
1969 "Bad type for register variable");
1970 llvm::MDNode *RegName = cast<llvm::MDNode>(
1971 cast<llvm::MetadataAsValue>(Dst.getGlobalReg())->getMetadata());
1972 assert(RegName && "Register LValue is not metadata");
1974 // We accept integer and pointer types only
1975 llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType());
1976 llvm::Type *Ty = OrigTy;
1977 if (OrigTy->isPointerTy())
1978 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
1979 llvm::Type *Types[] = { Ty };
1981 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types);
1982 llvm::Value *Value = Src.getScalarVal();
1983 if (OrigTy->isPointerTy())
1984 Value = Builder.CreatePtrToInt(Value, Ty);
1986 F, {llvm::MetadataAsValue::get(Ty->getContext(), RegName), Value});
1989 // setObjCGCLValueClass - sets class of the lvalue for the purpose of
1990 // generating write-barries API. It is currently a global, ivar,
1992 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
1994 bool IsMemberAccess=false) {
1995 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC)
1998 if (isa<ObjCIvarRefExpr>(E)) {
1999 QualType ExpTy = E->getType();
2000 if (IsMemberAccess && ExpTy->isPointerType()) {
2001 // If ivar is a structure pointer, assigning to field of
2002 // this struct follows gcc's behavior and makes it a non-ivar
2003 // writer-barrier conservatively.
2004 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
2005 if (ExpTy->isRecordType()) {
2006 LV.setObjCIvar(false);
2010 LV.setObjCIvar(true);
2011 auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E));
2012 LV.setBaseIvarExp(Exp->getBase());
2013 LV.setObjCArray(E->getType()->isArrayType());
2017 if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) {
2018 if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
2019 if (VD->hasGlobalStorage()) {
2020 LV.setGlobalObjCRef(true);
2021 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None);
2024 LV.setObjCArray(E->getType()->isArrayType());
2028 if (const auto *Exp = dyn_cast<UnaryOperator>(E)) {
2029 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2033 if (const auto *Exp = dyn_cast<ParenExpr>(E)) {
2034 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2035 if (LV.isObjCIvar()) {
2036 // If cast is to a structure pointer, follow gcc's behavior and make it
2037 // a non-ivar write-barrier.
2038 QualType ExpTy = E->getType();
2039 if (ExpTy->isPointerType())
2040 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
2041 if (ExpTy->isRecordType())
2042 LV.setObjCIvar(false);
2047 if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) {
2048 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV);
2052 if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) {
2053 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2057 if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) {
2058 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2062 if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) {
2063 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
2067 if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
2068 setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
2069 if (LV.isObjCIvar() && !LV.isObjCArray())
2070 // Using array syntax to assigning to what an ivar points to is not
2071 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
2072 LV.setObjCIvar(false);
2073 else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
2074 // Using array syntax to assigning to what global points to is not
2075 // same as assigning to the global itself. {id *G;} G[i] = 0;
2076 LV.setGlobalObjCRef(false);
2080 if (const auto *Exp = dyn_cast<MemberExpr>(E)) {
2081 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true);
2082 // We don't know if member is an 'ivar', but this flag is looked at
2083 // only in the context of LV.isObjCIvar().
2084 LV.setObjCArray(E->getType()->isArrayType());
2089 static llvm::Value *
2090 EmitBitCastOfLValueToProperType(CodeGenFunction &CGF,
2091 llvm::Value *V, llvm::Type *IRType,
2092 StringRef Name = StringRef()) {
2093 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace();
2094 return CGF.Builder.CreateBitCast(V, IRType->getPointerTo(AS), Name);
2097 static LValue EmitThreadPrivateVarDeclLValue(
2098 CodeGenFunction &CGF, const VarDecl *VD, QualType T, Address Addr,
2099 llvm::Type *RealVarTy, SourceLocation Loc) {
2100 Addr = CGF.CGM.getOpenMPRuntime().getAddrOfThreadPrivate(CGF, VD, Addr, Loc);
2101 Addr = CGF.Builder.CreateElementBitCast(Addr, RealVarTy);
2102 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2103 return CGF.MakeAddrLValue(Addr, T, BaseInfo);
2106 Address CodeGenFunction::EmitLoadOfReference(Address Addr,
2107 const ReferenceType *RefTy,
2108 LValueBaseInfo *BaseInfo) {
2109 llvm::Value *Ptr = Builder.CreateLoad(Addr);
2110 return Address(Ptr, getNaturalTypeAlignment(RefTy->getPointeeType(),
2111 BaseInfo, /*forPointee*/ true));
2114 LValue CodeGenFunction::EmitLoadOfReferenceLValue(Address RefAddr,
2115 const ReferenceType *RefTy) {
2116 LValueBaseInfo BaseInfo;
2117 Address Addr = EmitLoadOfReference(RefAddr, RefTy, &BaseInfo);
2118 return MakeAddrLValue(Addr, RefTy->getPointeeType(), BaseInfo);
2121 Address CodeGenFunction::EmitLoadOfPointer(Address Ptr,
2122 const PointerType *PtrTy,
2123 LValueBaseInfo *BaseInfo) {
2124 llvm::Value *Addr = Builder.CreateLoad(Ptr);
2125 return Address(Addr, getNaturalTypeAlignment(PtrTy->getPointeeType(),
2127 /*forPointeeType=*/true));
2130 LValue CodeGenFunction::EmitLoadOfPointerLValue(Address PtrAddr,
2131 const PointerType *PtrTy) {
2132 LValueBaseInfo BaseInfo;
2133 Address Addr = EmitLoadOfPointer(PtrAddr, PtrTy, &BaseInfo);
2134 return MakeAddrLValue(Addr, PtrTy->getPointeeType(), BaseInfo);
2137 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
2138 const Expr *E, const VarDecl *VD) {
2139 QualType T = E->getType();
2141 // If it's thread_local, emit a call to its wrapper function instead.
2142 if (VD->getTLSKind() == VarDecl::TLS_Dynamic &&
2143 CGF.CGM.getCXXABI().usesThreadWrapperFunction())
2144 return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T);
2146 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
2147 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType());
2148 V = EmitBitCastOfLValueToProperType(CGF, V, RealVarTy);
2149 CharUnits Alignment = CGF.getContext().getDeclAlign(VD);
2150 Address Addr(V, Alignment);
2152 // Emit reference to the private copy of the variable if it is an OpenMP
2153 // threadprivate variable.
2154 if (CGF.getLangOpts().OpenMP && VD->hasAttr<OMPThreadPrivateDeclAttr>())
2155 return EmitThreadPrivateVarDeclLValue(CGF, VD, T, Addr, RealVarTy,
2157 if (auto RefTy = VD->getType()->getAs<ReferenceType>()) {
2158 LV = CGF.EmitLoadOfReferenceLValue(Addr, RefTy);
2160 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2161 LV = CGF.MakeAddrLValue(Addr, T, BaseInfo);
2163 setObjCGCLValueClass(CGF.getContext(), E, LV);
2167 static llvm::Constant *EmitFunctionDeclPointer(CodeGenModule &CGM,
2168 const FunctionDecl *FD) {
2169 if (FD->hasAttr<WeakRefAttr>()) {
2170 ConstantAddress aliasee = CGM.GetWeakRefReference(FD);
2171 return aliasee.getPointer();
2174 llvm::Constant *V = CGM.GetAddrOfFunction(FD);
2175 if (!FD->hasPrototype()) {
2176 if (const FunctionProtoType *Proto =
2177 FD->getType()->getAs<FunctionProtoType>()) {
2178 // Ugly case: for a K&R-style definition, the type of the definition
2179 // isn't the same as the type of a use. Correct for this with a
2181 QualType NoProtoType =
2182 CGM.getContext().getFunctionNoProtoType(Proto->getReturnType());
2183 NoProtoType = CGM.getContext().getPointerType(NoProtoType);
2184 V = llvm::ConstantExpr::getBitCast(V,
2185 CGM.getTypes().ConvertType(NoProtoType));
2191 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
2192 const Expr *E, const FunctionDecl *FD) {
2193 llvm::Value *V = EmitFunctionDeclPointer(CGF.CGM, FD);
2194 CharUnits Alignment = CGF.getContext().getDeclAlign(FD);
2195 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2196 return CGF.MakeAddrLValue(V, E->getType(), Alignment, BaseInfo);
2199 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD,
2200 llvm::Value *ThisValue) {
2201 QualType TagType = CGF.getContext().getTagDeclType(FD->getParent());
2202 LValue LV = CGF.MakeNaturalAlignAddrLValue(ThisValue, TagType);
2203 return CGF.EmitLValueForField(LV, FD);
2206 /// Named Registers are named metadata pointing to the register name
2207 /// which will be read from/written to as an argument to the intrinsic
2208 /// @llvm.read/write_register.
2209 /// So far, only the name is being passed down, but other options such as
2210 /// register type, allocation type or even optimization options could be
2211 /// passed down via the metadata node.
2212 static LValue EmitGlobalNamedRegister(const VarDecl *VD, CodeGenModule &CGM) {
2213 SmallString<64> Name("llvm.named.register.");
2214 AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>();
2215 assert(Asm->getLabel().size() < 64-Name.size() &&
2216 "Register name too big");
2217 Name.append(Asm->getLabel());
2218 llvm::NamedMDNode *M =
2219 CGM.getModule().getOrInsertNamedMetadata(Name);
2220 if (M->getNumOperands() == 0) {
2221 llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(),
2223 llvm::Metadata *Ops[] = {Str};
2224 M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
2227 CharUnits Alignment = CGM.getContext().getDeclAlign(VD);
2230 llvm::MetadataAsValue::get(CGM.getLLVMContext(), M->getOperand(0));
2231 return LValue::MakeGlobalReg(Address(Ptr, Alignment), VD->getType());
2234 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
2235 const NamedDecl *ND = E->getDecl();
2236 QualType T = E->getType();
2238 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2239 // Global Named registers access via intrinsics only
2240 if (VD->getStorageClass() == SC_Register &&
2241 VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl())
2242 return EmitGlobalNamedRegister(VD, CGM);
2244 // A DeclRefExpr for a reference initialized by a constant expression can
2245 // appear without being odr-used. Directly emit the constant initializer.
2246 const Expr *Init = VD->getAnyInitializer(VD);
2247 if (Init && !isa<ParmVarDecl>(VD) && VD->getType()->isReferenceType() &&
2248 VD->isUsableInConstantExpressions(getContext()) &&
2249 VD->checkInitIsICE() &&
2250 // Do not emit if it is private OpenMP variable.
2251 !(E->refersToEnclosingVariableOrCapture() && CapturedStmtInfo &&
2252 LocalDeclMap.count(VD))) {
2253 llvm::Constant *Val =
2254 CGM.EmitConstantValue(*VD->evaluateValue(), VD->getType(), this);
2255 assert(Val && "failed to emit reference constant expression");
2256 // FIXME: Eventually we will want to emit vector element references.
2258 // Should we be using the alignment of the constant pointer we emitted?
2259 CharUnits Alignment = getNaturalTypeAlignment(E->getType(), nullptr,
2261 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2262 return MakeAddrLValue(Address(Val, Alignment), T, BaseInfo);
2265 // Check for captured variables.
2266 if (E->refersToEnclosingVariableOrCapture()) {
2267 if (auto *FD = LambdaCaptureFields.lookup(VD))
2268 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue);
2269 else if (CapturedStmtInfo) {
2270 auto I = LocalDeclMap.find(VD);
2271 if (I != LocalDeclMap.end()) {
2272 if (auto RefTy = VD->getType()->getAs<ReferenceType>())
2273 return EmitLoadOfReferenceLValue(I->second, RefTy);
2274 return MakeAddrLValue(I->second, T);
2277 EmitCapturedFieldLValue(*this, CapturedStmtInfo->lookup(VD),
2278 CapturedStmtInfo->getContextValue());
2279 bool MayAlias = CapLVal.getBaseInfo().getMayAlias();
2280 return MakeAddrLValue(
2281 Address(CapLVal.getPointer(), getContext().getDeclAlign(VD)),
2282 CapLVal.getType(), LValueBaseInfo(AlignmentSource::Decl, MayAlias));
2285 assert(isa<BlockDecl>(CurCodeDecl));
2286 Address addr = GetAddrOfBlockDecl(VD, VD->hasAttr<BlocksAttr>());
2287 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2288 return MakeAddrLValue(addr, T, BaseInfo);
2292 // FIXME: We should be able to assert this for FunctionDecls as well!
2293 // FIXME: We should be able to assert this for all DeclRefExprs, not just
2294 // those with a valid source location.
2295 assert((ND->isUsed(false) || !isa<VarDecl>(ND) ||
2296 !E->getLocation().isValid()) &&
2297 "Should not use decl without marking it used!");
2299 if (ND->hasAttr<WeakRefAttr>()) {
2300 const auto *VD = cast<ValueDecl>(ND);
2301 ConstantAddress Aliasee = CGM.GetWeakRefReference(VD);
2302 return MakeAddrLValue(Aliasee, T,
2303 LValueBaseInfo(AlignmentSource::Decl, false));
2306 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
2307 // Check if this is a global variable.
2308 if (VD->hasLinkage() || VD->isStaticDataMember())
2309 return EmitGlobalVarDeclLValue(*this, E, VD);
2311 Address addr = Address::invalid();
2313 // The variable should generally be present in the local decl map.
2314 auto iter = LocalDeclMap.find(VD);
2315 if (iter != LocalDeclMap.end()) {
2316 addr = iter->second;
2318 // Otherwise, it might be static local we haven't emitted yet for
2319 // some reason; most likely, because it's in an outer function.
2320 } else if (VD->isStaticLocal()) {
2321 addr = Address(CGM.getOrCreateStaticVarDecl(
2322 *VD, CGM.getLLVMLinkageVarDefinition(VD, /*isConstant=*/false)),
2323 getContext().getDeclAlign(VD));
2325 // No other cases for now.
2327 llvm_unreachable("DeclRefExpr for Decl not entered in LocalDeclMap?");
2331 // Check for OpenMP threadprivate variables.
2332 if (getLangOpts().OpenMP && VD->hasAttr<OMPThreadPrivateDeclAttr>()) {
2333 return EmitThreadPrivateVarDeclLValue(
2334 *this, VD, T, addr, getTypes().ConvertTypeForMem(VD->getType()),
2338 // Drill into block byref variables.
2339 bool isBlockByref = VD->hasAttr<BlocksAttr>();
2341 addr = emitBlockByrefAddress(addr, VD);
2344 // Drill into reference types.
2346 if (auto RefTy = VD->getType()->getAs<ReferenceType>()) {
2347 LV = EmitLoadOfReferenceLValue(addr, RefTy);
2349 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2350 LV = MakeAddrLValue(addr, T, BaseInfo);
2353 bool isLocalStorage = VD->hasLocalStorage();
2355 bool NonGCable = isLocalStorage &&
2356 !VD->getType()->isReferenceType() &&
2359 LV.getQuals().removeObjCGCAttr();
2363 bool isImpreciseLifetime =
2364 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>());
2365 if (isImpreciseLifetime)
2366 LV.setARCPreciseLifetime(ARCImpreciseLifetime);
2367 setObjCGCLValueClass(getContext(), E, LV);
2371 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
2372 return EmitFunctionDeclLValue(*this, E, FD);
2374 // FIXME: While we're emitting a binding from an enclosing scope, all other
2375 // DeclRefExprs we see should be implicitly treated as if they also refer to
2376 // an enclosing scope.
2377 if (const auto *BD = dyn_cast<BindingDecl>(ND))
2378 return EmitLValue(BD->getBinding());
2380 llvm_unreachable("Unhandled DeclRefExpr");
2383 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
2384 // __extension__ doesn't affect lvalue-ness.
2385 if (E->getOpcode() == UO_Extension)
2386 return EmitLValue(E->getSubExpr());
2388 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
2389 switch (E->getOpcode()) {
2390 default: llvm_unreachable("Unknown unary operator lvalue!");
2392 QualType T = E->getSubExpr()->getType()->getPointeeType();
2393 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
2395 LValueBaseInfo BaseInfo;
2396 Address Addr = EmitPointerWithAlignment(E->getSubExpr(), &BaseInfo);
2397 LValue LV = MakeAddrLValue(Addr, T, BaseInfo);
2398 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
2400 // We should not generate __weak write barrier on indirect reference
2401 // of a pointer to object; as in void foo (__weak id *param); *param = 0;
2402 // But, we continue to generate __strong write barrier on indirect write
2403 // into a pointer to object.
2404 if (getLangOpts().ObjC1 &&
2405 getLangOpts().getGC() != LangOptions::NonGC &&
2407 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
2412 LValue LV = EmitLValue(E->getSubExpr());
2413 assert(LV.isSimple() && "real/imag on non-ordinary l-value");
2415 // __real is valid on scalars. This is a faster way of testing that.
2416 // __imag can only produce an rvalue on scalars.
2417 if (E->getOpcode() == UO_Real &&
2418 !LV.getAddress().getElementType()->isStructTy()) {
2419 assert(E->getSubExpr()->getType()->isArithmeticType());
2423 QualType T = ExprTy->castAs<ComplexType>()->getElementType();
2426 (E->getOpcode() == UO_Real
2427 ? emitAddrOfRealComponent(LV.getAddress(), LV.getType())
2428 : emitAddrOfImagComponent(LV.getAddress(), LV.getType()));
2429 LValue ElemLV = MakeAddrLValue(Component, T, LV.getBaseInfo());
2430 ElemLV.getQuals().addQualifiers(LV.getQuals());
2435 LValue LV = EmitLValue(E->getSubExpr());
2436 bool isInc = E->getOpcode() == UO_PreInc;
2438 if (E->getType()->isAnyComplexType())
2439 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
2441 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
2447 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
2448 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
2450 LValueBaseInfo(AlignmentSource::Decl, false));
2453 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
2454 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
2456 LValueBaseInfo(AlignmentSource::Decl, false));
2459 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
2460 auto SL = E->getFunctionName();
2461 assert(SL != nullptr && "No StringLiteral name in PredefinedExpr");
2462 StringRef FnName = CurFn->getName();
2463 if (FnName.startswith("\01"))
2464 FnName = FnName.substr(1);
2465 StringRef NameItems[] = {
2466 PredefinedExpr::getIdentTypeName(E->getIdentType()), FnName};
2467 std::string GVName = llvm::join(NameItems, NameItems + 2, ".");
2468 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
2469 if (auto *BD = dyn_cast<BlockDecl>(CurCodeDecl)) {
2470 std::string Name = SL->getString();
2471 if (!Name.empty()) {
2472 unsigned Discriminator =
2473 CGM.getCXXABI().getMangleContext().getBlockId(BD, true);
2475 Name += "_" + Twine(Discriminator + 1).str();
2476 auto C = CGM.GetAddrOfConstantCString(Name, GVName.c_str());
2477 return MakeAddrLValue(C, E->getType(), BaseInfo);
2479 auto C = CGM.GetAddrOfConstantCString(FnName, GVName.c_str());
2480 return MakeAddrLValue(C, E->getType(), BaseInfo);
2483 auto C = CGM.GetAddrOfConstantStringFromLiteral(SL, GVName);
2484 return MakeAddrLValue(C, E->getType(), BaseInfo);
2487 /// Emit a type description suitable for use by a runtime sanitizer library. The
2488 /// format of a type descriptor is
2491 /// { i16 TypeKind, i16 TypeInfo }
2494 /// followed by an array of i8 containing the type name. TypeKind is 0 for an
2495 /// integer, 1 for a floating point value, and -1 for anything else.
2496 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) {
2497 // Only emit each type's descriptor once.
2498 if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T))
2501 uint16_t TypeKind = -1;
2502 uint16_t TypeInfo = 0;
2504 if (T->isIntegerType()) {
2506 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) |
2507 (T->isSignedIntegerType() ? 1 : 0);
2508 } else if (T->isFloatingType()) {
2510 TypeInfo = getContext().getTypeSize(T);
2513 // Format the type name as if for a diagnostic, including quotes and
2514 // optionally an 'aka'.
2515 SmallString<32> Buffer;
2516 CGM.getDiags().ConvertArgToString(DiagnosticsEngine::ak_qualtype,
2517 (intptr_t)T.getAsOpaquePtr(),
2518 StringRef(), StringRef(), None, Buffer,
2521 llvm::Constant *Components[] = {
2522 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo),
2523 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer)
2525 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components);
2527 auto *GV = new llvm::GlobalVariable(
2528 CGM.getModule(), Descriptor->getType(),
2529 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor);
2530 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2531 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(GV);
2533 // Remember the descriptor for this type.
2534 CGM.setTypeDescriptorInMap(T, GV);
2539 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) {
2540 llvm::Type *TargetTy = IntPtrTy;
2542 // Floating-point types which fit into intptr_t are bitcast to integers
2543 // and then passed directly (after zero-extension, if necessary).
2544 if (V->getType()->isFloatingPointTy()) {
2545 unsigned Bits = V->getType()->getPrimitiveSizeInBits();
2546 if (Bits <= TargetTy->getIntegerBitWidth())
2547 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(),
2551 // Integers which fit in intptr_t are zero-extended and passed directly.
2552 if (V->getType()->isIntegerTy() &&
2553 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth())
2554 return Builder.CreateZExt(V, TargetTy);
2556 // Pointers are passed directly, everything else is passed by address.
2557 if (!V->getType()->isPointerTy()) {
2558 Address Ptr = CreateDefaultAlignTempAlloca(V->getType());
2559 Builder.CreateStore(V, Ptr);
2560 V = Ptr.getPointer();
2562 return Builder.CreatePtrToInt(V, TargetTy);
2565 /// \brief Emit a representation of a SourceLocation for passing to a handler
2566 /// in a sanitizer runtime library. The format for this data is:
2568 /// struct SourceLocation {
2569 /// const char *Filename;
2570 /// int32_t Line, Column;
2573 /// For an invalid SourceLocation, the Filename pointer is null.
2574 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
2575 llvm::Constant *Filename;
2578 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc);
2579 if (PLoc.isValid()) {
2580 StringRef FilenameString = PLoc.getFilename();
2582 int PathComponentsToStrip =
2583 CGM.getCodeGenOpts().EmitCheckPathComponentsToStrip;
2584 if (PathComponentsToStrip < 0) {
2585 assert(PathComponentsToStrip != INT_MIN);
2586 int PathComponentsToKeep = -PathComponentsToStrip;
2587 auto I = llvm::sys::path::rbegin(FilenameString);
2588 auto E = llvm::sys::path::rend(FilenameString);
2589 while (I != E && --PathComponentsToKeep)
2592 FilenameString = FilenameString.substr(I - E);
2593 } else if (PathComponentsToStrip > 0) {
2594 auto I = llvm::sys::path::begin(FilenameString);
2595 auto E = llvm::sys::path::end(FilenameString);
2596 while (I != E && PathComponentsToStrip--)
2601 FilenameString.substr(I - llvm::sys::path::begin(FilenameString));
2603 FilenameString = llvm::sys::path::filename(FilenameString);
2606 auto FilenameGV = CGM.GetAddrOfConstantCString(FilenameString, ".src");
2607 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(
2608 cast<llvm::GlobalVariable>(FilenameGV.getPointer()));
2609 Filename = FilenameGV.getPointer();
2610 Line = PLoc.getLine();
2611 Column = PLoc.getColumn();
2613 Filename = llvm::Constant::getNullValue(Int8PtrTy);
2617 llvm::Constant *Data[] = {Filename, Builder.getInt32(Line),
2618 Builder.getInt32(Column)};
2620 return llvm::ConstantStruct::getAnon(Data);
2624 /// \brief Specify under what conditions this check can be recovered
2625 enum class CheckRecoverableKind {
2626 /// Always terminate program execution if this check fails.
2628 /// Check supports recovering, runtime has both fatal (noreturn) and
2629 /// non-fatal handlers for this check.
2631 /// Runtime conditionally aborts, always need to support recovery.
2636 static CheckRecoverableKind getRecoverableKind(SanitizerMask Kind) {
2637 assert(llvm::countPopulation(Kind) == 1);
2639 case SanitizerKind::Vptr:
2640 return CheckRecoverableKind::AlwaysRecoverable;
2641 case SanitizerKind::Return:
2642 case SanitizerKind::Unreachable:
2643 return CheckRecoverableKind::Unrecoverable;
2645 return CheckRecoverableKind::Recoverable;
2650 struct SanitizerHandlerInfo {
2651 char const *const Name;
2656 const SanitizerHandlerInfo SanitizerHandlers[] = {
2657 #define SANITIZER_CHECK(Enum, Name, Version) {#Name, Version},
2658 LIST_SANITIZER_CHECKS
2659 #undef SANITIZER_CHECK
2662 static void emitCheckHandlerCall(CodeGenFunction &CGF,
2663 llvm::FunctionType *FnType,
2664 ArrayRef<llvm::Value *> FnArgs,
2665 SanitizerHandler CheckHandler,
2666 CheckRecoverableKind RecoverKind, bool IsFatal,
2667 llvm::BasicBlock *ContBB) {
2668 assert(IsFatal || RecoverKind != CheckRecoverableKind::Unrecoverable);
2669 bool NeedsAbortSuffix =
2670 IsFatal && RecoverKind != CheckRecoverableKind::Unrecoverable;
2671 const SanitizerHandlerInfo &CheckInfo = SanitizerHandlers[CheckHandler];
2672 const StringRef CheckName = CheckInfo.Name;
2673 std::string FnName =
2674 ("__ubsan_handle_" + CheckName +
2675 (CheckInfo.Version ? "_v" + llvm::utostr(CheckInfo.Version) : "") +
2676 (NeedsAbortSuffix ? "_abort" : ""))
2679 !IsFatal || RecoverKind == CheckRecoverableKind::AlwaysRecoverable;
2681 llvm::AttrBuilder B;
2683 B.addAttribute(llvm::Attribute::NoReturn)
2684 .addAttribute(llvm::Attribute::NoUnwind);
2686 B.addAttribute(llvm::Attribute::UWTable);
2688 llvm::Value *Fn = CGF.CGM.CreateRuntimeFunction(
2690 llvm::AttributeList::get(CGF.getLLVMContext(),
2691 llvm::AttributeList::FunctionIndex, B),
2693 llvm::CallInst *HandlerCall = CGF.EmitNounwindRuntimeCall(Fn, FnArgs);
2695 HandlerCall->setDoesNotReturn();
2696 CGF.Builder.CreateUnreachable();
2698 CGF.Builder.CreateBr(ContBB);
2702 void CodeGenFunction::EmitCheck(
2703 ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
2704 SanitizerHandler CheckHandler, ArrayRef<llvm::Constant *> StaticArgs,
2705 ArrayRef<llvm::Value *> DynamicArgs) {
2706 assert(IsSanitizerScope);
2707 assert(Checked.size() > 0);
2708 assert(CheckHandler >= 0 &&
2709 CheckHandler < sizeof(SanitizerHandlers) / sizeof(*SanitizerHandlers));
2710 const StringRef CheckName = SanitizerHandlers[CheckHandler].Name;
2712 llvm::Value *FatalCond = nullptr;
2713 llvm::Value *RecoverableCond = nullptr;
2714 llvm::Value *TrapCond = nullptr;
2715 for (int i = 0, n = Checked.size(); i < n; ++i) {
2716 llvm::Value *Check = Checked[i].first;
2717 // -fsanitize-trap= overrides -fsanitize-recover=.
2718 llvm::Value *&Cond =
2719 CGM.getCodeGenOpts().SanitizeTrap.has(Checked[i].second)
2721 : CGM.getCodeGenOpts().SanitizeRecover.has(Checked[i].second)
2724 Cond = Cond ? Builder.CreateAnd(Cond, Check) : Check;
2728 EmitTrapCheck(TrapCond);
2729 if (!FatalCond && !RecoverableCond)
2732 llvm::Value *JointCond;
2733 if (FatalCond && RecoverableCond)
2734 JointCond = Builder.CreateAnd(FatalCond, RecoverableCond);
2736 JointCond = FatalCond ? FatalCond : RecoverableCond;
2739 CheckRecoverableKind RecoverKind = getRecoverableKind(Checked[0].second);
2740 assert(SanOpts.has(Checked[0].second));
2742 for (int i = 1, n = Checked.size(); i < n; ++i) {
2743 assert(RecoverKind == getRecoverableKind(Checked[i].second) &&
2744 "All recoverable kinds in a single check must be same!");
2745 assert(SanOpts.has(Checked[i].second));
2749 llvm::BasicBlock *Cont = createBasicBlock("cont");
2750 llvm::BasicBlock *Handlers = createBasicBlock("handler." + CheckName);
2751 llvm::Instruction *Branch = Builder.CreateCondBr(JointCond, Cont, Handlers);
2752 // Give hint that we very much don't expect to execute the handler
2753 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
2754 llvm::MDBuilder MDHelper(getLLVMContext());
2755 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
2756 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node);
2757 EmitBlock(Handlers);
2759 // Handler functions take an i8* pointing to the (handler-specific) static
2760 // information block, followed by a sequence of intptr_t arguments
2761 // representing operand values.
2762 SmallVector<llvm::Value *, 4> Args;
2763 SmallVector<llvm::Type *, 4> ArgTypes;
2764 Args.reserve(DynamicArgs.size() + 1);
2765 ArgTypes.reserve(DynamicArgs.size() + 1);
2767 // Emit handler arguments and create handler function type.
2768 if (!StaticArgs.empty()) {
2769 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
2771 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
2772 llvm::GlobalVariable::PrivateLinkage, Info);
2773 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2774 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
2775 Args.push_back(Builder.CreateBitCast(InfoPtr, Int8PtrTy));
2776 ArgTypes.push_back(Int8PtrTy);
2779 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) {
2780 Args.push_back(EmitCheckValue(DynamicArgs[i]));
2781 ArgTypes.push_back(IntPtrTy);
2784 llvm::FunctionType *FnType =
2785 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false);
2787 if (!FatalCond || !RecoverableCond) {
2788 // Simple case: we need to generate a single handler call, either
2789 // fatal, or non-fatal.
2790 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind,
2791 (FatalCond != nullptr), Cont);
2793 // Emit two handler calls: first one for set of unrecoverable checks,
2794 // another one for recoverable.
2795 llvm::BasicBlock *NonFatalHandlerBB =
2796 createBasicBlock("non_fatal." + CheckName);
2797 llvm::BasicBlock *FatalHandlerBB = createBasicBlock("fatal." + CheckName);
2798 Builder.CreateCondBr(FatalCond, NonFatalHandlerBB, FatalHandlerBB);
2799 EmitBlock(FatalHandlerBB);
2800 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, true,
2802 EmitBlock(NonFatalHandlerBB);
2803 emitCheckHandlerCall(*this, FnType, Args, CheckHandler, RecoverKind, false,
2810 void CodeGenFunction::EmitCfiSlowPathCheck(
2811 SanitizerMask Kind, llvm::Value *Cond, llvm::ConstantInt *TypeId,
2812 llvm::Value *Ptr, ArrayRef<llvm::Constant *> StaticArgs) {
2813 llvm::BasicBlock *Cont = createBasicBlock("cfi.cont");
2815 llvm::BasicBlock *CheckBB = createBasicBlock("cfi.slowpath");
2816 llvm::BranchInst *BI = Builder.CreateCondBr(Cond, Cont, CheckBB);
2818 llvm::MDBuilder MDHelper(getLLVMContext());
2819 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
2820 BI->setMetadata(llvm::LLVMContext::MD_prof, Node);
2824 bool WithDiag = !CGM.getCodeGenOpts().SanitizeTrap.has(Kind);
2826 llvm::CallInst *CheckCall;
2828 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
2830 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
2831 llvm::GlobalVariable::PrivateLinkage, Info);
2832 InfoPtr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2833 CGM.getSanitizerMetadata()->disableSanitizerForGlobal(InfoPtr);
2835 llvm::Constant *SlowPathDiagFn = CGM.getModule().getOrInsertFunction(
2836 "__cfi_slowpath_diag",
2837 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy},
2839 CheckCall = Builder.CreateCall(
2841 {TypeId, Ptr, Builder.CreateBitCast(InfoPtr, Int8PtrTy)});
2843 llvm::Constant *SlowPathFn = CGM.getModule().getOrInsertFunction(
2845 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy}, false));
2846 CheckCall = Builder.CreateCall(SlowPathFn, {TypeId, Ptr});
2849 CheckCall->setDoesNotThrow();
2854 // Emit a stub for __cfi_check function so that the linker knows about this
2855 // symbol in LTO mode.
2856 void CodeGenFunction::EmitCfiCheckStub() {
2857 llvm::Module *M = &CGM.getModule();
2858 auto &Ctx = M->getContext();
2859 llvm::Function *F = llvm::Function::Create(
2860 llvm::FunctionType::get(VoidTy, {Int64Ty, Int8PtrTy, Int8PtrTy}, false),
2861 llvm::GlobalValue::WeakAnyLinkage, "__cfi_check", M);
2862 llvm::BasicBlock *BB = llvm::BasicBlock::Create(Ctx, "entry", F);
2863 // FIXME: consider emitting an intrinsic call like
2864 // call void @llvm.cfi_check(i64 %0, i8* %1, i8* %2)
2865 // which can be lowered in CrossDSOCFI pass to the actual contents of
2866 // __cfi_check. This would allow inlining of __cfi_check calls.
2867 llvm::CallInst::Create(
2868 llvm::Intrinsic::getDeclaration(M, llvm::Intrinsic::trap), "", BB);
2869 llvm::ReturnInst::Create(Ctx, nullptr, BB);
2872 // This function is basically a switch over the CFI failure kind, which is
2873 // extracted from CFICheckFailData (1st function argument). Each case is either
2874 // llvm.trap or a call to one of the two runtime handlers, based on
2875 // -fsanitize-trap and -fsanitize-recover settings. Default case (invalid
2876 // failure kind) traps, but this should really never happen. CFICheckFailData
2877 // can be nullptr if the calling module has -fsanitize-trap behavior for this
2878 // check kind; in this case __cfi_check_fail traps as well.
2879 void CodeGenFunction::EmitCfiCheckFail() {
2880 SanitizerScope SanScope(this);
2881 FunctionArgList Args;
2882 ImplicitParamDecl ArgData(getContext(), getContext().VoidPtrTy,
2883 ImplicitParamDecl::Other);
2884 ImplicitParamDecl ArgAddr(getContext(), getContext().VoidPtrTy,
2885 ImplicitParamDecl::Other);
2886 Args.push_back(&ArgData);
2887 Args.push_back(&ArgAddr);
2889 const CGFunctionInfo &FI =
2890 CGM.getTypes().arrangeBuiltinFunctionDeclaration(getContext().VoidTy, Args);
2892 llvm::Function *F = llvm::Function::Create(
2893 llvm::FunctionType::get(VoidTy, {VoidPtrTy, VoidPtrTy}, false),
2894 llvm::GlobalValue::WeakODRLinkage, "__cfi_check_fail", &CGM.getModule());
2895 F->setVisibility(llvm::GlobalValue::HiddenVisibility);
2897 StartFunction(GlobalDecl(), CGM.getContext().VoidTy, F, FI, Args,
2901 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgData), /*Volatile=*/false,
2902 CGM.getContext().VoidPtrTy, ArgData.getLocation());
2904 EmitLoadOfScalar(GetAddrOfLocalVar(&ArgAddr), /*Volatile=*/false,
2905 CGM.getContext().VoidPtrTy, ArgAddr.getLocation());
2907 // Data == nullptr means the calling module has trap behaviour for this check.
2908 llvm::Value *DataIsNotNullPtr =
2909 Builder.CreateICmpNE(Data, llvm::ConstantPointerNull::get(Int8PtrTy));
2910 EmitTrapCheck(DataIsNotNullPtr);
2912 llvm::StructType *SourceLocationTy =
2913 llvm::StructType::get(VoidPtrTy, Int32Ty, Int32Ty);
2914 llvm::StructType *CfiCheckFailDataTy =
2915 llvm::StructType::get(Int8Ty, SourceLocationTy, VoidPtrTy);
2917 llvm::Value *V = Builder.CreateConstGEP2_32(
2919 Builder.CreatePointerCast(Data, CfiCheckFailDataTy->getPointerTo(0)), 0,
2921 Address CheckKindAddr(V, getIntAlign());
2922 llvm::Value *CheckKind = Builder.CreateLoad(CheckKindAddr);
2924 llvm::Value *AllVtables = llvm::MetadataAsValue::get(
2925 CGM.getLLVMContext(),
2926 llvm::MDString::get(CGM.getLLVMContext(), "all-vtables"));
2927 llvm::Value *ValidVtable = Builder.CreateZExt(
2928 Builder.CreateCall(CGM.getIntrinsic(llvm::Intrinsic::type_test),
2929 {Addr, AllVtables}),
2932 const std::pair<int, SanitizerMask> CheckKinds[] = {
2933 {CFITCK_VCall, SanitizerKind::CFIVCall},
2934 {CFITCK_NVCall, SanitizerKind::CFINVCall},
2935 {CFITCK_DerivedCast, SanitizerKind::CFIDerivedCast},
2936 {CFITCK_UnrelatedCast, SanitizerKind::CFIUnrelatedCast},
2937 {CFITCK_ICall, SanitizerKind::CFIICall}};
2939 SmallVector<std::pair<llvm::Value *, SanitizerMask>, 5> Checks;
2940 for (auto CheckKindMaskPair : CheckKinds) {
2941 int Kind = CheckKindMaskPair.first;
2942 SanitizerMask Mask = CheckKindMaskPair.second;
2944 Builder.CreateICmpNE(CheckKind, llvm::ConstantInt::get(Int8Ty, Kind));
2945 if (CGM.getLangOpts().Sanitize.has(Mask))
2946 EmitCheck(std::make_pair(Cond, Mask), SanitizerHandler::CFICheckFail, {},
2947 {Data, Addr, ValidVtable});
2949 EmitTrapCheck(Cond);
2953 // The only reference to this function will be created during LTO link.
2954 // Make sure it survives until then.
2955 CGM.addUsedGlobal(F);
2958 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked) {
2959 llvm::BasicBlock *Cont = createBasicBlock("cont");
2961 // If we're optimizing, collapse all calls to trap down to just one per
2962 // function to save on code size.
2963 if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB) {
2964 TrapBB = createBasicBlock("trap");
2965 Builder.CreateCondBr(Checked, Cont, TrapBB);
2967 llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
2968 TrapCall->setDoesNotReturn();
2969 TrapCall->setDoesNotThrow();
2970 Builder.CreateUnreachable();
2972 Builder.CreateCondBr(Checked, Cont, TrapBB);
2978 llvm::CallInst *CodeGenFunction::EmitTrapCall(llvm::Intrinsic::ID IntrID) {
2979 llvm::CallInst *TrapCall = Builder.CreateCall(CGM.getIntrinsic(IntrID));
2981 if (!CGM.getCodeGenOpts().TrapFuncName.empty()) {
2982 auto A = llvm::Attribute::get(getLLVMContext(), "trap-func-name",
2983 CGM.getCodeGenOpts().TrapFuncName);
2984 TrapCall->addAttribute(llvm::AttributeList::FunctionIndex, A);
2990 Address CodeGenFunction::EmitArrayToPointerDecay(const Expr *E,
2991 LValueBaseInfo *BaseInfo) {
2992 assert(E->getType()->isArrayType() &&
2993 "Array to pointer decay must have array source type!");
2995 // Expressions of array type can't be bitfields or vector elements.
2996 LValue LV = EmitLValue(E);
2997 Address Addr = LV.getAddress();
2998 if (BaseInfo) *BaseInfo = LV.getBaseInfo();
3000 // If the array type was an incomplete type, we need to make sure
3001 // the decay ends up being the right type.
3002 llvm::Type *NewTy = ConvertType(E->getType());
3003 Addr = Builder.CreateElementBitCast(Addr, NewTy);
3005 // Note that VLA pointers are always decayed, so we don't need to do
3007 if (!E->getType()->isVariableArrayType()) {
3008 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3009 "Expected pointer to array");
3010 Addr = Builder.CreateStructGEP(Addr, 0, CharUnits::Zero(), "arraydecay");
3013 QualType EltType = E->getType()->castAsArrayTypeUnsafe()->getElementType();
3014 return Builder.CreateElementBitCast(Addr, ConvertTypeForMem(EltType));
3017 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
3018 /// array to pointer, return the array subexpression.
3019 static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
3020 // If this isn't just an array->pointer decay, bail out.
3021 const auto *CE = dyn_cast<CastExpr>(E);
3022 if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay)
3025 // If this is a decay from variable width array, bail out.
3026 const Expr *SubExpr = CE->getSubExpr();
3027 if (SubExpr->getType()->isVariableArrayType())
3033 static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF,
3035 ArrayRef<llvm::Value*> indices,
3039 const llvm::Twine &name = "arrayidx") {
3041 return CGF.EmitCheckedInBoundsGEP(ptr, indices, signedIndices, loc, name);
3043 return CGF.Builder.CreateGEP(ptr, indices, name);
3047 static CharUnits getArrayElementAlign(CharUnits arrayAlign,
3049 CharUnits eltSize) {
3050 // If we have a constant index, we can use the exact offset of the
3051 // element we're accessing.
3052 if (auto constantIdx = dyn_cast<llvm::ConstantInt>(idx)) {
3053 CharUnits offset = constantIdx->getZExtValue() * eltSize;
3054 return arrayAlign.alignmentAtOffset(offset);
3056 // Otherwise, use the worst-case alignment for any element.
3058 return arrayAlign.alignmentOfArrayElement(eltSize);
3062 static QualType getFixedSizeElementType(const ASTContext &ctx,
3063 const VariableArrayType *vla) {
3066 eltType = vla->getElementType();
3067 } while ((vla = ctx.getAsVariableArrayType(eltType)));
3071 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr,
3072 ArrayRef<llvm::Value *> indices,
3073 QualType eltType, bool inbounds,
3074 bool signedIndices, SourceLocation loc,
3075 const llvm::Twine &name = "arrayidx") {
3076 // All the indices except that last must be zero.
3078 for (auto idx : indices.drop_back())
3079 assert(isa<llvm::ConstantInt>(idx) &&
3080 cast<llvm::ConstantInt>(idx)->isZero());
3083 // Determine the element size of the statically-sized base. This is
3084 // the thing that the indices are expressed in terms of.
3085 if (auto vla = CGF.getContext().getAsVariableArrayType(eltType)) {
3086 eltType = getFixedSizeElementType(CGF.getContext(), vla);
3089 // We can use that to compute the best alignment of the element.
3090 CharUnits eltSize = CGF.getContext().getTypeSizeInChars(eltType);
3091 CharUnits eltAlign =
3092 getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize);
3094 llvm::Value *eltPtr = emitArraySubscriptGEP(
3095 CGF, addr.getPointer(), indices, inbounds, signedIndices, loc, name);
3096 return Address(eltPtr, eltAlign);
3099 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
3101 // The index must always be an integer, which is not an aggregate. Emit it
3102 // in lexical order (this complexity is, sadly, required by C++17).
3103 llvm::Value *IdxPre =
3104 (E->getLHS() == E->getIdx()) ? EmitScalarExpr(E->getIdx()) : nullptr;
3105 bool SignedIndices = false;
3106 auto EmitIdxAfterBase = [&, IdxPre](bool Promote) -> llvm::Value * {
3108 if (E->getLHS() != E->getIdx()) {
3109 assert(E->getRHS() == E->getIdx() && "index was neither LHS nor RHS");
3110 Idx = EmitScalarExpr(E->getIdx());
3113 QualType IdxTy = E->getIdx()->getType();
3114 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType();
3115 SignedIndices |= IdxSigned;
3117 if (SanOpts.has(SanitizerKind::ArrayBounds))
3118 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed);
3120 // Extend or truncate the index type to 32 or 64-bits.
3121 if (Promote && Idx->getType() != IntPtrTy)
3122 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
3128 // If the base is a vector type, then we are forming a vector element lvalue
3129 // with this subscript.
3130 if (E->getBase()->getType()->isVectorType() &&
3131 !isa<ExtVectorElementExpr>(E->getBase())) {
3132 // Emit the vector as an lvalue to get its address.
3133 LValue LHS = EmitLValue(E->getBase());
3134 auto *Idx = EmitIdxAfterBase(/*Promote*/false);
3135 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
3136 return LValue::MakeVectorElt(LHS.getAddress(), Idx,
3137 E->getBase()->getType(),
3141 // All the other cases basically behave like simple offsetting.
3143 // Handle the extvector case we ignored above.
3144 if (isa<ExtVectorElementExpr>(E->getBase())) {
3145 LValue LV = EmitLValue(E->getBase());
3146 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3147 Address Addr = EmitExtVectorElementLValue(LV);
3149 QualType EltType = LV.getType()->castAs<VectorType>()->getElementType();
3150 Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true,
3151 SignedIndices, E->getExprLoc());
3152 return MakeAddrLValue(Addr, EltType, LV.getBaseInfo());
3155 LValueBaseInfo BaseInfo;
3156 Address Addr = Address::invalid();
3157 if (const VariableArrayType *vla =
3158 getContext().getAsVariableArrayType(E->getType())) {
3159 // The base must be a pointer, which is not an aggregate. Emit
3160 // it. It needs to be emitted first in case it's what captures
3162 Addr = EmitPointerWithAlignment(E->getBase(), &BaseInfo);
3163 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3165 // The element count here is the total number of non-VLA elements.
3166 llvm::Value *numElements = getVLASize(vla).first;
3168 // Effectively, the multiply by the VLA size is part of the GEP.
3169 // GEP indexes are signed, and scaling an index isn't permitted to
3170 // signed-overflow, so we use the same semantics for our explicit
3171 // multiply. We suppress this if overflow is not undefined behavior.
3172 if (getLangOpts().isSignedOverflowDefined()) {
3173 Idx = Builder.CreateMul(Idx, numElements);
3175 Idx = Builder.CreateNSWMul(Idx, numElements);
3178 Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(),
3179 !getLangOpts().isSignedOverflowDefined(),
3180 SignedIndices, E->getExprLoc());
3182 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
3183 // Indexing over an interface, as in "NSString *P; P[4];"
3185 // Emit the base pointer.
3186 Addr = EmitPointerWithAlignment(E->getBase(), &BaseInfo);
3187 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3189 CharUnits InterfaceSize = getContext().getTypeSizeInChars(OIT);
3190 llvm::Value *InterfaceSizeVal =
3191 llvm::ConstantInt::get(Idx->getType(), InterfaceSize.getQuantity());
3193 llvm::Value *ScaledIdx = Builder.CreateMul(Idx, InterfaceSizeVal);
3195 // We don't necessarily build correct LLVM struct types for ObjC
3196 // interfaces, so we can't rely on GEP to do this scaling
3197 // correctly, so we need to cast to i8*. FIXME: is this actually
3198 // true? A lot of other things in the fragile ABI would break...
3199 llvm::Type *OrigBaseTy = Addr.getType();
3200 Addr = Builder.CreateElementBitCast(Addr, Int8Ty);
3203 CharUnits EltAlign =
3204 getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize);
3205 llvm::Value *EltPtr =
3206 emitArraySubscriptGEP(*this, Addr.getPointer(), ScaledIdx, false,
3207 SignedIndices, E->getExprLoc());
3208 Addr = Address(EltPtr, EltAlign);
3211 Addr = Builder.CreateBitCast(Addr, OrigBaseTy);
3212 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3213 // If this is A[i] where A is an array, the frontend will have decayed the
3214 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3215 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3216 // "gep x, i" here. Emit one "gep A, 0, i".
3217 assert(Array->getType()->isArrayType() &&
3218 "Array to pointer decay must have array source type!");
3220 // For simple multidimensional array indexing, set the 'accessed' flag for
3221 // better bounds-checking of the base expression.
3222 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3223 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3225 ArrayLV = EmitLValue(Array);
3226 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3228 // Propagate the alignment from the array itself to the result.
3229 Addr = emitArraySubscriptGEP(
3230 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
3231 E->getType(), !getLangOpts().isSignedOverflowDefined(), SignedIndices,
3233 BaseInfo = ArrayLV.getBaseInfo();
3235 // The base must be a pointer; emit it with an estimate of its alignment.
3236 Addr = EmitPointerWithAlignment(E->getBase(), &BaseInfo);
3237 auto *Idx = EmitIdxAfterBase(/*Promote*/true);
3238 Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(),
3239 !getLangOpts().isSignedOverflowDefined(),
3240 SignedIndices, E->getExprLoc());
3243 LValue LV = MakeAddrLValue(Addr, E->getType(), BaseInfo);
3245 // TODO: Preserve/extend path TBAA metadata?
3247 if (getLangOpts().ObjC1 &&
3248 getLangOpts().getGC() != LangOptions::NonGC) {
3249 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
3250 setObjCGCLValueClass(getContext(), E, LV);
3255 static Address emitOMPArraySectionBase(CodeGenFunction &CGF, const Expr *Base,
3256 LValueBaseInfo &BaseInfo,
3257 QualType BaseTy, QualType ElTy,
3258 bool IsLowerBound) {
3260 if (auto *ASE = dyn_cast<OMPArraySectionExpr>(Base->IgnoreParenImpCasts())) {
3261 BaseLVal = CGF.EmitOMPArraySectionExpr(ASE, IsLowerBound);
3262 if (BaseTy->isArrayType()) {
3263 Address Addr = BaseLVal.getAddress();
3264 BaseInfo = BaseLVal.getBaseInfo();
3266 // If the array type was an incomplete type, we need to make sure
3267 // the decay ends up being the right type.
3268 llvm::Type *NewTy = CGF.ConvertType(BaseTy);
3269 Addr = CGF.Builder.CreateElementBitCast(Addr, NewTy);
3271 // Note that VLA pointers are always decayed, so we don't need to do
3273 if (!BaseTy->isVariableArrayType()) {
3274 assert(isa<llvm::ArrayType>(Addr.getElementType()) &&
3275 "Expected pointer to array");
3276 Addr = CGF.Builder.CreateStructGEP(Addr, 0, CharUnits::Zero(),
3280 return CGF.Builder.CreateElementBitCast(Addr,
3281 CGF.ConvertTypeForMem(ElTy));
3283 LValueBaseInfo TypeInfo;
3284 CharUnits Align = CGF.getNaturalTypeAlignment(ElTy, &TypeInfo);
3285 BaseInfo.mergeForCast(TypeInfo);
3286 return Address(CGF.Builder.CreateLoad(BaseLVal.getAddress()), Align);
3288 return CGF.EmitPointerWithAlignment(Base, &BaseInfo);
3291 LValue CodeGenFunction::EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
3292 bool IsLowerBound) {
3295 dyn_cast<OMPArraySectionExpr>(E->getBase()->IgnoreParenImpCasts()))
3296 BaseTy = OMPArraySectionExpr::getBaseOriginalType(ASE);
3298 BaseTy = E->getBase()->getType();
3299 QualType ResultExprTy;
3300 if (auto *AT = getContext().getAsArrayType(BaseTy))
3301 ResultExprTy = AT->getElementType();
3303 ResultExprTy = BaseTy->getPointeeType();
3304 llvm::Value *Idx = nullptr;
3305 if (IsLowerBound || E->getColonLoc().isInvalid()) {
3306 // Requesting lower bound or upper bound, but without provided length and
3307 // without ':' symbol for the default length -> length = 1.
3308 // Idx = LowerBound ?: 0;
3309 if (auto *LowerBound = E->getLowerBound()) {
3310 Idx = Builder.CreateIntCast(
3311 EmitScalarExpr(LowerBound), IntPtrTy,
3312 LowerBound->getType()->hasSignedIntegerRepresentation());
3314 Idx = llvm::ConstantInt::getNullValue(IntPtrTy);
3316 // Try to emit length or lower bound as constant. If this is possible, 1
3317 // is subtracted from constant length or lower bound. Otherwise, emit LLVM
3318 // IR (LB + Len) - 1.
3319 auto &C = CGM.getContext();
3320 auto *Length = E->getLength();
3321 llvm::APSInt ConstLength;
3323 // Idx = LowerBound + Length - 1;
3324 if (Length->isIntegerConstantExpr(ConstLength, C)) {
3325 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3328 auto *LowerBound = E->getLowerBound();
3329 llvm::APSInt ConstLowerBound(PointerWidthInBits, /*isUnsigned=*/false);
3330 if (LowerBound && LowerBound->isIntegerConstantExpr(ConstLowerBound, C)) {
3331 ConstLowerBound = ConstLowerBound.zextOrTrunc(PointerWidthInBits);
3332 LowerBound = nullptr;
3336 else if (!LowerBound)
3339 if (Length || LowerBound) {
3340 auto *LowerBoundVal =
3342 ? Builder.CreateIntCast(
3343 EmitScalarExpr(LowerBound), IntPtrTy,
3344 LowerBound->getType()->hasSignedIntegerRepresentation())
3345 : llvm::ConstantInt::get(IntPtrTy, ConstLowerBound);
3348 ? Builder.CreateIntCast(
3349 EmitScalarExpr(Length), IntPtrTy,
3350 Length->getType()->hasSignedIntegerRepresentation())
3351 : llvm::ConstantInt::get(IntPtrTy, ConstLength);
3352 Idx = Builder.CreateAdd(LowerBoundVal, LengthVal, "lb_add_len",
3354 !getLangOpts().isSignedOverflowDefined());
3355 if (Length && LowerBound) {
3356 Idx = Builder.CreateSub(
3357 Idx, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "idx_sub_1",
3358 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3361 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength + ConstLowerBound);
3363 // Idx = ArraySize - 1;
3364 QualType ArrayTy = BaseTy->isPointerType()
3365 ? E->getBase()->IgnoreParenImpCasts()->getType()
3367 if (auto *VAT = C.getAsVariableArrayType(ArrayTy)) {
3368 Length = VAT->getSizeExpr();
3369 if (Length->isIntegerConstantExpr(ConstLength, C))
3372 auto *CAT = C.getAsConstantArrayType(ArrayTy);
3373 ConstLength = CAT->getSize();
3376 auto *LengthVal = Builder.CreateIntCast(
3377 EmitScalarExpr(Length), IntPtrTy,
3378 Length->getType()->hasSignedIntegerRepresentation());
3379 Idx = Builder.CreateSub(
3380 LengthVal, llvm::ConstantInt::get(IntPtrTy, /*V=*/1), "len_sub_1",
3381 /*HasNUW=*/false, !getLangOpts().isSignedOverflowDefined());
3383 ConstLength = ConstLength.zextOrTrunc(PointerWidthInBits);
3385 Idx = llvm::ConstantInt::get(IntPtrTy, ConstLength);
3391 Address EltPtr = Address::invalid();
3392 LValueBaseInfo BaseInfo;
3393 if (auto *VLA = getContext().getAsVariableArrayType(ResultExprTy)) {
3394 // The base must be a pointer, which is not an aggregate. Emit
3395 // it. It needs to be emitted first in case it's what captures
3398 emitOMPArraySectionBase(*this, E->getBase(), BaseInfo, BaseTy,
3399 VLA->getElementType(), IsLowerBound);
3400 // The element count here is the total number of non-VLA elements.
3401 llvm::Value *NumElements = getVLASize(VLA).first;
3403 // Effectively, the multiply by the VLA size is part of the GEP.
3404 // GEP indexes are signed, and scaling an index isn't permitted to
3405 // signed-overflow, so we use the same semantics for our explicit
3406 // multiply. We suppress this if overflow is not undefined behavior.
3407 if (getLangOpts().isSignedOverflowDefined())
3408 Idx = Builder.CreateMul(Idx, NumElements);
3410 Idx = Builder.CreateNSWMul(Idx, NumElements);
3411 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(),
3412 !getLangOpts().isSignedOverflowDefined(),
3413 /*SignedIndices=*/false, E->getExprLoc());
3414 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
3415 // If this is A[i] where A is an array, the frontend will have decayed the
3416 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
3417 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
3418 // "gep x, i" here. Emit one "gep A, 0, i".
3419 assert(Array->getType()->isArrayType() &&
3420 "Array to pointer decay must have array source type!");
3422 // For simple multidimensional array indexing, set the 'accessed' flag for
3423 // better bounds-checking of the base expression.
3424 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
3425 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
3427 ArrayLV = EmitLValue(Array);
3429 // Propagate the alignment from the array itself to the result.
3430 EltPtr = emitArraySubscriptGEP(
3431 *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
3432 ResultExprTy, !getLangOpts().isSignedOverflowDefined(),
3433 /*SignedIndices=*/false, E->getExprLoc());
3434 BaseInfo = ArrayLV.getBaseInfo();
3436 Address Base = emitOMPArraySectionBase(*this, E->getBase(), BaseInfo,
3437 BaseTy, ResultExprTy, IsLowerBound);
3438 EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy,
3439 !getLangOpts().isSignedOverflowDefined(),
3440 /*SignedIndices=*/false, E->getExprLoc());
3443 return MakeAddrLValue(EltPtr, ResultExprTy, BaseInfo);
3446 LValue CodeGenFunction::
3447 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
3448 // Emit the base vector as an l-value.
3451 // ExtVectorElementExpr's base can either be a vector or pointer to vector.
3453 // If it is a pointer to a vector, emit the address and form an lvalue with
3455 LValueBaseInfo BaseInfo;
3456 Address Ptr = EmitPointerWithAlignment(E->getBase(), &BaseInfo);
3457 const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
3458 Base = MakeAddrLValue(Ptr, PT->getPointeeType(), BaseInfo);
3459 Base.getQuals().removeObjCGCAttr();
3460 } else if (E->getBase()->isGLValue()) {
3461 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
3462 // emit the base as an lvalue.
3463 assert(E->getBase()->getType()->isVectorType());
3464 Base = EmitLValue(E->getBase());
3466 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
3467 assert(E->getBase()->getType()->isVectorType() &&
3468 "Result must be a vector");
3469 llvm::Value *Vec = EmitScalarExpr(E->getBase());
3471 // Store the vector to memory (because LValue wants an address).
3472 Address VecMem = CreateMemTemp(E->getBase()->getType());
3473 Builder.CreateStore(Vec, VecMem);
3474 Base = MakeAddrLValue(VecMem, E->getBase()->getType(),
3475 LValueBaseInfo(AlignmentSource::Decl, false));
3479 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers());
3481 // Encode the element access list into a vector of unsigned indices.
3482 SmallVector<uint32_t, 4> Indices;
3483 E->getEncodedElementAccess(Indices);
3485 if (Base.isSimple()) {
3486 llvm::Constant *CV =
3487 llvm::ConstantDataVector::get(getLLVMContext(), Indices);
3488 return LValue::MakeExtVectorElt(Base.getAddress(), CV, type,
3489 Base.getBaseInfo());
3491 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
3493 llvm::Constant *BaseElts = Base.getExtVectorElts();
3494 SmallVector<llvm::Constant *, 4> CElts;
3496 for (unsigned i = 0, e = Indices.size(); i != e; ++i)
3497 CElts.push_back(BaseElts->getAggregateElement(Indices[i]));
3498 llvm::Constant *CV = llvm::ConstantVector::get(CElts);
3499 return LValue::MakeExtVectorElt(Base.getExtVectorAddress(), CV, type,
3500 Base.getBaseInfo());
3503 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
3504 Expr *BaseExpr = E->getBase();
3505 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
3508 LValueBaseInfo BaseInfo;
3509 Address Addr = EmitPointerWithAlignment(BaseExpr, &BaseInfo);
3510 QualType PtrTy = BaseExpr->getType()->getPointeeType();
3511 SanitizerSet SkippedChecks;
3512 bool IsBaseCXXThis = IsWrappedCXXThis(BaseExpr);
3514 SkippedChecks.set(SanitizerKind::Alignment, true);
3515 if (IsBaseCXXThis || isa<DeclRefExpr>(BaseExpr))
3516 SkippedChecks.set(SanitizerKind::Null, true);
3517 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Addr.getPointer(), PtrTy,
3518 /*Alignment=*/CharUnits::Zero(), SkippedChecks);
3519 BaseLV = MakeAddrLValue(Addr, PtrTy, BaseInfo);
3521 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess);
3523 NamedDecl *ND = E->getMemberDecl();
3524 if (auto *Field = dyn_cast<FieldDecl>(ND)) {
3525 LValue LV = EmitLValueForField(BaseLV, Field);
3526 setObjCGCLValueClass(getContext(), E, LV);
3530 if (auto *VD = dyn_cast<VarDecl>(ND))
3531 return EmitGlobalVarDeclLValue(*this, E, VD);
3533 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
3534 return EmitFunctionDeclLValue(*this, E, FD);
3536 llvm_unreachable("Unhandled member declaration!");
3539 /// Given that we are currently emitting a lambda, emit an l-value for
3540 /// one of its members.
3541 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) {
3542 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent()->isLambda());
3543 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent() == Field->getParent());
3544 QualType LambdaTagType =
3545 getContext().getTagDeclType(Field->getParent());
3546 LValue LambdaLV = MakeNaturalAlignAddrLValue(CXXABIThisValue, LambdaTagType);
3547 return EmitLValueForField(LambdaLV, Field);
3550 /// Drill down to the storage of a field without walking into
3551 /// reference types.
3553 /// The resulting address doesn't necessarily have the right type.
3554 static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base,
3555 const FieldDecl *field) {
3556 const RecordDecl *rec = field->getParent();
3559 CGF.CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
3562 // Adjust the alignment down to the given offset.
3563 // As a special case, if the LLVM field index is 0, we know that this
3565 assert((idx != 0 || CGF.getContext().getASTRecordLayout(rec)
3566 .getFieldOffset(field->getFieldIndex()) == 0) &&
3567 "LLVM field at index zero had non-zero offset?");
3569 auto &recLayout = CGF.getContext().getASTRecordLayout(rec);
3570 auto offsetInBits = recLayout.getFieldOffset(field->getFieldIndex());
3571 offset = CGF.getContext().toCharUnitsFromBits(offsetInBits);
3574 return CGF.Builder.CreateStructGEP(base, idx, offset, field->getName());
3577 static bool hasAnyVptr(const QualType Type, const ASTContext &Context) {
3578 const auto *RD = Type.getTypePtr()->getAsCXXRecordDecl();
3582 if (RD->isDynamicClass())
3585 for (const auto &Base : RD->bases())
3586 if (hasAnyVptr(Base.getType(), Context))
3589 for (const FieldDecl *Field : RD->fields())
3590 if (hasAnyVptr(Field->getType(), Context))
3596 LValue CodeGenFunction::EmitLValueForField(LValue base,
3597 const FieldDecl *field) {
3598 LValueBaseInfo BaseInfo = base.getBaseInfo();
3599 AlignmentSource fieldAlignSource =
3600 getFieldAlignmentSource(BaseInfo.getAlignmentSource());
3601 LValueBaseInfo FieldBaseInfo(fieldAlignSource, BaseInfo.getMayAlias());
3603 const RecordDecl *rec = field->getParent();
3604 if (rec->isUnion() || rec->hasAttr<MayAliasAttr>())
3605 FieldBaseInfo.setMayAlias(true);
3606 bool mayAlias = FieldBaseInfo.getMayAlias();
3608 if (field->isBitField()) {
3609 const CGRecordLayout &RL =
3610 CGM.getTypes().getCGRecordLayout(field->getParent());
3611 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field);
3612 Address Addr = base.getAddress();
3613 unsigned Idx = RL.getLLVMFieldNo(field);
3615 // For structs, we GEP to the field that the record layout suggests.
3616 Addr = Builder.CreateStructGEP(Addr, Idx, Info.StorageOffset,
3618 // Get the access type.
3619 llvm::Type *FieldIntTy =
3620 llvm::Type::getIntNTy(getLLVMContext(), Info.StorageSize);
3621 if (Addr.getElementType() != FieldIntTy)
3622 Addr = Builder.CreateElementBitCast(Addr, FieldIntTy);
3624 QualType fieldType =
3625 field->getType().withCVRQualifiers(base.getVRQualifiers());
3626 return LValue::MakeBitfield(Addr, Info, fieldType, FieldBaseInfo);
3629 QualType type = field->getType();
3630 Address addr = base.getAddress();
3631 unsigned cvr = base.getVRQualifiers();
3632 bool TBAAPath = CGM.getCodeGenOpts().StructPathTBAA;
3633 if (rec->isUnion()) {
3634 // For unions, there is no pointer adjustment.
3635 assert(!type->isReferenceType() && "union has reference member");
3636 // TODO: handle path-aware TBAA for union.
3639 const auto FieldType = field->getType();
3640 if (CGM.getCodeGenOpts().StrictVTablePointers &&
3641 hasAnyVptr(FieldType, getContext()))
3642 // Because unions can easily skip invariant.barriers, we need to add
3643 // a barrier every time CXXRecord field with vptr is referenced.
3644 addr = Address(Builder.CreateInvariantGroupBarrier(addr.getPointer()),
3645 addr.getAlignment());
3647 // For structs, we GEP to the field that the record layout suggests.
3648 addr = emitAddrOfFieldStorage(*this, addr, field);
3650 // If this is a reference field, load the reference right now.
3651 if (const ReferenceType *refType = type->getAs<ReferenceType>()) {
3652 llvm::LoadInst *load = Builder.CreateLoad(addr, "ref");
3653 if (cvr & Qualifiers::Volatile) load->setVolatile(true);
3655 // Loading the reference will disable path-aware TBAA.
3657 if (CGM.shouldUseTBAA()) {
3660 tbaa = CGM.getTBAAInfo(getContext().CharTy);
3662 tbaa = CGM.getTBAAInfo(type);
3664 CGM.DecorateInstructionWithTBAA(load, tbaa);
3668 type = refType->getPointeeType();
3670 CharUnits alignment =
3671 getNaturalTypeAlignment(type, &FieldBaseInfo, /*pointee*/ true);
3672 FieldBaseInfo.setMayAlias(false);
3673 addr = Address(load, alignment);
3675 // Qualifiers on the struct don't apply to the referencee, and
3676 // we'll pick up CVR from the actual type later, so reset these
3677 // additional qualifiers now.
3682 // Make sure that the address is pointing to the right type. This is critical
3683 // for both unions and structs. A union needs a bitcast, a struct element
3684 // will need a bitcast if the LLVM type laid out doesn't match the desired
3686 addr = Builder.CreateElementBitCast(addr,
3687 CGM.getTypes().ConvertTypeForMem(type),
3690 if (field->hasAttr<AnnotateAttr>())
3691 addr = EmitFieldAnnotations(field, addr);
3693 LValue LV = MakeAddrLValue(addr, type, FieldBaseInfo);
3694 LV.getQuals().addCVRQualifiers(cvr);
3696 const ASTRecordLayout &Layout =
3697 getContext().getASTRecordLayout(field->getParent());
3698 // Set the base type to be the base type of the base LValue and
3699 // update offset to be relative to the base type.
3700 LV.setTBAABaseType(mayAlias ? getContext().CharTy : base.getTBAABaseType());
3701 LV.setTBAAOffset(mayAlias ? 0 : base.getTBAAOffset() +
3702 Layout.getFieldOffset(field->getFieldIndex()) /
3703 getContext().getCharWidth());
3706 // __weak attribute on a field is ignored.
3707 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
3708 LV.getQuals().removeObjCGCAttr();
3710 // Fields of may_alias structs act like 'char' for TBAA purposes.
3711 // FIXME: this should get propagated down through anonymous structs
3713 if (mayAlias && LV.getTBAAInfo())
3714 LV.setTBAAInfo(CGM.getTBAAInfo(getContext().CharTy));
3720 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base,
3721 const FieldDecl *Field) {
3722 QualType FieldType = Field->getType();
3724 if (!FieldType->isReferenceType())
3725 return EmitLValueForField(Base, Field);
3727 Address V = emitAddrOfFieldStorage(*this, Base.getAddress(), Field);
3729 // Make sure that the address is pointing to the right type.
3730 llvm::Type *llvmType = ConvertTypeForMem(FieldType);
3731 V = Builder.CreateElementBitCast(V, llvmType, Field->getName());
3733 // TODO: access-path TBAA?
3734 LValueBaseInfo BaseInfo = Base.getBaseInfo();
3735 LValueBaseInfo FieldBaseInfo(
3736 getFieldAlignmentSource(BaseInfo.getAlignmentSource()),
3737 BaseInfo.getMayAlias());
3738 return MakeAddrLValue(V, FieldType, FieldBaseInfo);
3741 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
3742 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
3743 if (E->isFileScope()) {
3744 ConstantAddress GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E);
3745 return MakeAddrLValue(GlobalPtr, E->getType(), BaseInfo);
3747 if (E->getType()->isVariablyModifiedType())
3748 // make sure to emit the VLA size.
3749 EmitVariablyModifiedType(E->getType());
3751 Address DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
3752 const Expr *InitExpr = E->getInitializer();
3753 LValue Result = MakeAddrLValue(DeclPtr, E->getType(), BaseInfo);
3755 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(),
3761 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) {
3762 if (!E->isGLValue())
3763 // Initializing an aggregate temporary in C++11: T{...}.
3764 return EmitAggExprToLValue(E);
3766 // An lvalue initializer list must be initializing a reference.
3767 assert(E->isTransparent() && "non-transparent glvalue init list");
3768 return EmitLValue(E->getInit(0));
3771 /// Emit the operand of a glvalue conditional operator. This is either a glvalue
3772 /// or a (possibly-parenthesized) throw-expression. If this is a throw, no
3773 /// LValue is returned and the current block has been terminated.
3774 static Optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF,
3775 const Expr *Operand) {
3776 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) {
3777 CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false);
3781 return CGF.EmitLValue(Operand);
3784 LValue CodeGenFunction::
3785 EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) {
3786 if (!expr->isGLValue()) {
3787 // ?: here should be an aggregate.
3788 assert(hasAggregateEvaluationKind(expr->getType()) &&
3789 "Unexpected conditional operator!");
3790 return EmitAggExprToLValue(expr);
3793 OpaqueValueMapping binding(*this, expr);
3795 const Expr *condExpr = expr->getCond();
3797 if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
3798 const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr();
3799 if (!CondExprBool) std::swap(live, dead);
3801 if (!ContainsLabel(dead)) {
3802 // If the true case is live, we need to track its region.
3804 incrementProfileCounter(expr);
3805 return EmitLValue(live);
3809 llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true");
3810 llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false");
3811 llvm::BasicBlock *contBlock = createBasicBlock("cond.end");
3813 ConditionalEvaluation eval(*this);
3814 EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock, getProfileCount(expr));
3816 // Any temporaries created here are conditional.
3817 EmitBlock(lhsBlock);
3818 incrementProfileCounter(expr);
3820 Optional<LValue> lhs =
3821 EmitLValueOrThrowExpression(*this, expr->getTrueExpr());
3824 if (lhs && !lhs->isSimple())
3825 return EmitUnsupportedLValue(expr, "conditional operator");
3827 lhsBlock = Builder.GetInsertBlock();
3829 Builder.CreateBr(contBlock);
3831 // Any temporaries created here are conditional.
3832 EmitBlock(rhsBlock);
3834 Optional<LValue> rhs =
3835 EmitLValueOrThrowExpression(*this, expr->getFalseExpr());
3837 if (rhs && !rhs->isSimple())
3838 return EmitUnsupportedLValue(expr, "conditional operator");
3839 rhsBlock = Builder.GetInsertBlock();
3841 EmitBlock(contBlock);
3844 llvm::PHINode *phi = Builder.CreatePHI(lhs->getPointer()->getType(),
3846 phi->addIncoming(lhs->getPointer(), lhsBlock);
3847 phi->addIncoming(rhs->getPointer(), rhsBlock);
3848 Address result(phi, std::min(lhs->getAlignment(), rhs->getAlignment()));
3849 AlignmentSource alignSource =
3850 std::max(lhs->getBaseInfo().getAlignmentSource(),
3851 rhs->getBaseInfo().getAlignmentSource());
3852 bool MayAlias = lhs->getBaseInfo().getMayAlias() ||
3853 rhs->getBaseInfo().getMayAlias();
3854 return MakeAddrLValue(result, expr->getType(),
3855 LValueBaseInfo(alignSource, MayAlias));
3857 assert((lhs || rhs) &&
3858 "both operands of glvalue conditional are throw-expressions?");
3859 return lhs ? *lhs : *rhs;
3863 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference
3864 /// type. If the cast is to a reference, we can have the usual lvalue result,
3865 /// otherwise if a cast is needed by the code generator in an lvalue context,
3866 /// then it must mean that we need the address of an aggregate in order to
3867 /// access one of its members. This can happen for all the reasons that casts
3868 /// are permitted with aggregate result, including noop aggregate casts, and
3869 /// cast from scalar to union.
3870 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
3871 switch (E->getCastKind()) {
3874 case CK_ArrayToPointerDecay:
3875 case CK_FunctionToPointerDecay:
3876 case CK_NullToMemberPointer:
3877 case CK_NullToPointer:
3878 case CK_IntegralToPointer:
3879 case CK_PointerToIntegral:
3880 case CK_PointerToBoolean:
3881 case CK_VectorSplat:
3882 case CK_IntegralCast:
3883 case CK_BooleanToSignedIntegral:
3884 case CK_IntegralToBoolean:
3885 case CK_IntegralToFloating:
3886 case CK_FloatingToIntegral:
3887 case CK_FloatingToBoolean:
3888 case CK_FloatingCast:
3889 case CK_FloatingRealToComplex:
3890 case CK_FloatingComplexToReal:
3891 case CK_FloatingComplexToBoolean:
3892 case CK_FloatingComplexCast:
3893 case CK_FloatingComplexToIntegralComplex:
3894 case CK_IntegralRealToComplex:
3895 case CK_IntegralComplexToReal:
3896 case CK_IntegralComplexToBoolean:
3897 case CK_IntegralComplexCast:
3898 case CK_IntegralComplexToFloatingComplex:
3899 case CK_DerivedToBaseMemberPointer:
3900 case CK_BaseToDerivedMemberPointer:
3901 case CK_MemberPointerToBoolean:
3902 case CK_ReinterpretMemberPointer:
3903 case CK_AnyPointerToBlockPointerCast:
3904 case CK_ARCProduceObject:
3905 case CK_ARCConsumeObject:
3906 case CK_ARCReclaimReturnedObject:
3907 case CK_ARCExtendBlockObject:
3908 case CK_CopyAndAutoreleaseBlockObject:
3909 case CK_AddressSpaceConversion:
3910 case CK_IntToOCLSampler:
3911 return EmitUnsupportedLValue(E, "unexpected cast lvalue");
3914 llvm_unreachable("dependent cast kind in IR gen!");
3916 case CK_BuiltinFnToFnPtr:
3917 llvm_unreachable("builtin functions are handled elsewhere");
3919 // These are never l-values; just use the aggregate emission code.
3920 case CK_NonAtomicToAtomic:
3921 case CK_AtomicToNonAtomic:
3922 return EmitAggExprToLValue(E);
3925 LValue LV = EmitLValue(E->getSubExpr());
3926 Address V = LV.getAddress();
3927 const auto *DCE = cast<CXXDynamicCastExpr>(E);
3928 return MakeNaturalAlignAddrLValue(EmitDynamicCast(V, DCE), E->getType());
3931 case CK_ConstructorConversion:
3932 case CK_UserDefinedConversion:
3933 case CK_CPointerToObjCPointerCast:
3934 case CK_BlockPointerToObjCPointerCast:
3936 case CK_LValueToRValue:
3937 return EmitLValue(E->getSubExpr());
3939 case CK_UncheckedDerivedToBase:
3940 case CK_DerivedToBase: {
3941 const RecordType *DerivedClassTy =
3942 E->getSubExpr()->getType()->getAs<RecordType>();
3943 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
3945 LValue LV = EmitLValue(E->getSubExpr());
3946 Address This = LV.getAddress();
3948 // Perform the derived-to-base conversion
3949 Address Base = GetAddressOfBaseClass(
3950 This, DerivedClassDecl, E->path_begin(), E->path_end(),
3951 /*NullCheckValue=*/false, E->getExprLoc());
3953 return MakeAddrLValue(Base, E->getType(), LV.getBaseInfo());
3956 return EmitAggExprToLValue(E);
3957 case CK_BaseToDerived: {
3958 const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
3959 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
3961 LValue LV = EmitLValue(E->getSubExpr());
3963 // Perform the base-to-derived conversion
3965 GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
3966 E->path_begin(), E->path_end(),
3967 /*NullCheckValue=*/false);
3969 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is
3970 // performed and the object is not of the derived type.
3971 if (sanitizePerformTypeCheck())
3972 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(),
3973 Derived.getPointer(), E->getType());
3975 if (SanOpts.has(SanitizerKind::CFIDerivedCast))
3976 EmitVTablePtrCheckForCast(E->getType(), Derived.getPointer(),
3977 /*MayBeNull=*/false,
3978 CFITCK_DerivedCast, E->getLocStart());
3980 return MakeAddrLValue(Derived, E->getType(), LV.getBaseInfo());
3982 case CK_LValueBitCast: {
3983 // This must be a reinterpret_cast (or c-style equivalent).
3984 const auto *CE = cast<ExplicitCastExpr>(E);
3986 CGM.EmitExplicitCastExprType(CE, this);
3987 LValue LV = EmitLValue(E->getSubExpr());
3988 Address V = Builder.CreateBitCast(LV.getAddress(),
3989 ConvertType(CE->getTypeAsWritten()));
3991 if (SanOpts.has(SanitizerKind::CFIUnrelatedCast))
3992 EmitVTablePtrCheckForCast(E->getType(), V.getPointer(),
3993 /*MayBeNull=*/false,
3994 CFITCK_UnrelatedCast, E->getLocStart());
3996 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo());
3998 case CK_ObjCObjectLValueCast: {
3999 LValue LV = EmitLValue(E->getSubExpr());
4000 Address V = Builder.CreateElementBitCast(LV.getAddress(),
4001 ConvertType(E->getType()));
4002 return MakeAddrLValue(V, E->getType(), LV.getBaseInfo());
4004 case CK_ZeroToOCLQueue:
4005 llvm_unreachable("NULL to OpenCL queue lvalue cast is not valid");
4006 case CK_ZeroToOCLEvent:
4007 llvm_unreachable("NULL to OpenCL event lvalue cast is not valid");
4010 llvm_unreachable("Unhandled lvalue cast kind?");
4013 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
4014 assert(OpaqueValueMappingData::shouldBindAsLValue(e));
4015 return getOpaqueLValueMapping(e);
4018 RValue CodeGenFunction::EmitRValueForField(LValue LV,
4019 const FieldDecl *FD,
4020 SourceLocation Loc) {
4021 QualType FT = FD->getType();
4022 LValue FieldLV = EmitLValueForField(LV, FD);
4023 switch (getEvaluationKind(FT)) {
4025 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc));
4027 return FieldLV.asAggregateRValue();
4029 // This routine is used to load fields one-by-one to perform a copy, so
4030 // don't load reference fields.
4031 if (FD->getType()->isReferenceType())
4032 return RValue::get(FieldLV.getPointer());
4033 return EmitLoadOfLValue(FieldLV, Loc);
4035 llvm_unreachable("bad evaluation kind");
4038 //===--------------------------------------------------------------------===//
4039 // Expression Emission
4040 //===--------------------------------------------------------------------===//
4042 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
4043 ReturnValueSlot ReturnValue) {
4044 // Builtins never have block type.
4045 if (E->getCallee()->getType()->isBlockPointerType())
4046 return EmitBlockCallExpr(E, ReturnValue);
4048 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E))
4049 return EmitCXXMemberCallExpr(CE, ReturnValue);
4051 if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E))
4052 return EmitCUDAKernelCallExpr(CE, ReturnValue);
4054 if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E))
4055 if (const CXXMethodDecl *MD =
4056 dyn_cast_or_null<CXXMethodDecl>(CE->getCalleeDecl()))
4057 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
4059 CGCallee callee = EmitCallee(E->getCallee());
4061 if (callee.isBuiltin()) {
4062 return EmitBuiltinExpr(callee.getBuiltinDecl(), callee.getBuiltinID(),
4066 if (callee.isPseudoDestructor()) {
4067 return EmitCXXPseudoDestructorExpr(callee.getPseudoDestructorExpr());
4070 return EmitCall(E->getCallee()->getType(), callee, E, ReturnValue);
4073 /// Emit a CallExpr without considering whether it might be a subclass.
4074 RValue CodeGenFunction::EmitSimpleCallExpr(const CallExpr *E,
4075 ReturnValueSlot ReturnValue) {
4076 CGCallee Callee = EmitCallee(E->getCallee());
4077 return EmitCall(E->getCallee()->getType(), Callee, E, ReturnValue);
4080 static CGCallee EmitDirectCallee(CodeGenFunction &CGF, const FunctionDecl *FD) {
4081 if (auto builtinID = FD->getBuiltinID()) {
4082 return CGCallee::forBuiltin(builtinID, FD);
4085 llvm::Constant *calleePtr = EmitFunctionDeclPointer(CGF.CGM, FD);
4086 return CGCallee::forDirect(calleePtr, FD);
4089 CGCallee CodeGenFunction::EmitCallee(const Expr *E) {
4090 E = E->IgnoreParens();
4092 // Look through function-to-pointer decay.
4093 if (auto ICE = dyn_cast<ImplicitCastExpr>(E)) {
4094 if (ICE->getCastKind() == CK_FunctionToPointerDecay ||
4095 ICE->getCastKind() == CK_BuiltinFnToFnPtr) {
4096 return EmitCallee(ICE->getSubExpr());
4099 // Resolve direct calls.
4100 } else if (auto DRE = dyn_cast<DeclRefExpr>(E)) {
4101 if (auto FD = dyn_cast<FunctionDecl>(DRE->getDecl())) {
4102 return EmitDirectCallee(*this, FD);
4104 } else if (auto ME = dyn_cast<MemberExpr>(E)) {
4105 if (auto FD = dyn_cast<FunctionDecl>(ME->getMemberDecl())) {
4106 EmitIgnoredExpr(ME->getBase());
4107 return EmitDirectCallee(*this, FD);
4110 // Look through template substitutions.
4111 } else if (auto NTTP = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
4112 return EmitCallee(NTTP->getReplacement());
4114 // Treat pseudo-destructor calls differently.
4115 } else if (auto PDE = dyn_cast<CXXPseudoDestructorExpr>(E)) {
4116 return CGCallee::forPseudoDestructor(PDE);
4119 // Otherwise, we have an indirect reference.
4120 llvm::Value *calleePtr;
4121 QualType functionType;
4122 if (auto ptrType = E->getType()->getAs<PointerType>()) {
4123 calleePtr = EmitScalarExpr(E);
4124 functionType = ptrType->getPointeeType();
4126 functionType = E->getType();
4127 calleePtr = EmitLValue(E).getPointer();
4129 assert(functionType->isFunctionType());
4130 CGCalleeInfo calleeInfo(functionType->getAs<FunctionProtoType>(),
4131 E->getReferencedDeclOfCallee());
4132 CGCallee callee(calleeInfo, calleePtr);
4136 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
4137 // Comma expressions just emit their LHS then their RHS as an l-value.
4138 if (E->getOpcode() == BO_Comma) {
4139 EmitIgnoredExpr(E->getLHS());
4140 EnsureInsertPoint();
4141 return EmitLValue(E->getRHS());
4144 if (E->getOpcode() == BO_PtrMemD ||
4145 E->getOpcode() == BO_PtrMemI)
4146 return EmitPointerToDataMemberBinaryExpr(E);
4148 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
4150 // Note that in all of these cases, __block variables need the RHS
4151 // evaluated first just in case the variable gets moved by the RHS.
4153 switch (getEvaluationKind(E->getType())) {
4155 switch (E->getLHS()->getType().getObjCLifetime()) {
4156 case Qualifiers::OCL_Strong:
4157 return EmitARCStoreStrong(E, /*ignored*/ false).first;
4159 case Qualifiers::OCL_Autoreleasing:
4160 return EmitARCStoreAutoreleasing(E).first;
4162 // No reason to do any of these differently.
4163 case Qualifiers::OCL_None:
4164 case Qualifiers::OCL_ExplicitNone:
4165 case Qualifiers::OCL_Weak:
4169 RValue RV = EmitAnyExpr(E->getRHS());
4170 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store);
4172 EmitNullabilityCheck(LV, RV.getScalarVal(), E->getExprLoc());
4173 EmitStoreThroughLValue(RV, LV);
4178 return EmitComplexAssignmentLValue(E);
4181 return EmitAggExprToLValue(E);
4183 llvm_unreachable("bad evaluation kind");
4186 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
4187 RValue RV = EmitCallExpr(E);
4190 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4191 LValueBaseInfo(AlignmentSource::Decl, false));
4193 assert(E->getCallReturnType(getContext())->isReferenceType() &&
4194 "Can't have a scalar return unless the return type is a "
4197 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4200 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
4201 // FIXME: This shouldn't require another copy.
4202 return EmitAggExprToLValue(E);
4205 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
4206 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
4207 && "binding l-value to type which needs a temporary");
4208 AggValueSlot Slot = CreateAggTemp(E->getType());
4209 EmitCXXConstructExpr(E, Slot);
4210 return MakeAddrLValue(Slot.getAddress(), E->getType(),
4211 LValueBaseInfo(AlignmentSource::Decl, false));
4215 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
4216 return MakeNaturalAlignAddrLValue(EmitCXXTypeidExpr(E), E->getType());
4219 Address CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) {
4220 return Builder.CreateElementBitCast(CGM.GetAddrOfUuidDescriptor(E),
4221 ConvertType(E->getType()));
4224 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) {
4225 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType(),
4226 LValueBaseInfo(AlignmentSource::Decl, false));
4230 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
4231 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
4232 Slot.setExternallyDestructed();
4233 EmitAggExpr(E->getSubExpr(), Slot);
4234 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddress());
4235 return MakeAddrLValue(Slot.getAddress(), E->getType(),
4236 LValueBaseInfo(AlignmentSource::Decl, false));
4240 CodeGenFunction::EmitLambdaLValue(const LambdaExpr *E) {
4241 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
4242 EmitLambdaExpr(E, Slot);
4243 return MakeAddrLValue(Slot.getAddress(), E->getType(),
4244 LValueBaseInfo(AlignmentSource::Decl, false));
4247 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
4248 RValue RV = EmitObjCMessageExpr(E);
4251 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4252 LValueBaseInfo(AlignmentSource::Decl, false));
4254 assert(E->getMethodDecl()->getReturnType()->isReferenceType() &&
4255 "Can't have a scalar return unless the return type is a "
4258 return MakeNaturalAlignPointeeAddrLValue(RV.getScalarVal(), E->getType());
4261 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
4263 CGM.getObjCRuntime().GetAddrOfSelector(*this, E->getSelector());
4264 return MakeAddrLValue(V, E->getType(),
4265 LValueBaseInfo(AlignmentSource::Decl, false));
4268 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
4269 const ObjCIvarDecl *Ivar) {
4270 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
4273 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
4274 llvm::Value *BaseValue,
4275 const ObjCIvarDecl *Ivar,
4276 unsigned CVRQualifiers) {
4277 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
4278 Ivar, CVRQualifiers);
4281 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
4282 // FIXME: A lot of the code below could be shared with EmitMemberExpr.
4283 llvm::Value *BaseValue = nullptr;
4284 const Expr *BaseExpr = E->getBase();
4285 Qualifiers BaseQuals;
4288 BaseValue = EmitScalarExpr(BaseExpr);
4289 ObjectTy = BaseExpr->getType()->getPointeeType();
4290 BaseQuals = ObjectTy.getQualifiers();
4292 LValue BaseLV = EmitLValue(BaseExpr);
4293 BaseValue = BaseLV.getPointer();
4294 ObjectTy = BaseExpr->getType();
4295 BaseQuals = ObjectTy.getQualifiers();
4299 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
4300 BaseQuals.getCVRQualifiers());
4301 setObjCGCLValueClass(getContext(), E, LV);
4305 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
4306 // Can only get l-value for message expression returning aggregate type
4307 RValue RV = EmitAnyExprToTemp(E);
4308 return MakeAddrLValue(RV.getAggregateAddress(), E->getType(),
4309 LValueBaseInfo(AlignmentSource::Decl, false));
4312 RValue CodeGenFunction::EmitCall(QualType CalleeType, const CGCallee &OrigCallee,
4313 const CallExpr *E, ReturnValueSlot ReturnValue,
4314 llvm::Value *Chain) {
4315 // Get the actual function type. The callee type will always be a pointer to
4316 // function type or a block pointer type.
4317 assert(CalleeType->isFunctionPointerType() &&
4318 "Call must have function pointer type!");
4320 const Decl *TargetDecl = OrigCallee.getAbstractInfo().getCalleeDecl();
4322 if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl))
4323 // We can only guarantee that a function is called from the correct
4324 // context/function based on the appropriate target attributes,
4325 // so only check in the case where we have both always_inline and target
4326 // since otherwise we could be making a conditional call after a check for
4327 // the proper cpu features (and it won't cause code generation issues due to
4328 // function based code generation).
4329 if (TargetDecl->hasAttr<AlwaysInlineAttr>() &&
4330 TargetDecl->hasAttr<TargetAttr>())
4331 checkTargetFeatures(E, FD);
4333 CalleeType = getContext().getCanonicalType(CalleeType);
4335 const auto *FnType =
4336 cast<FunctionType>(cast<PointerType>(CalleeType)->getPointeeType());
4338 CGCallee Callee = OrigCallee;
4340 if (getLangOpts().CPlusPlus && SanOpts.has(SanitizerKind::Function) &&
4341 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
4342 if (llvm::Constant *PrefixSig =
4343 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) {
4344 SanitizerScope SanScope(this);
4345 llvm::Constant *FTRTTIConst =
4346 CGM.GetAddrOfRTTIDescriptor(QualType(FnType, 0), /*ForEH=*/true);
4347 llvm::Type *PrefixStructTyElems[] = {
4348 PrefixSig->getType(),
4349 FTRTTIConst->getType()
4351 llvm::StructType *PrefixStructTy = llvm::StructType::get(
4352 CGM.getLLVMContext(), PrefixStructTyElems, /*isPacked=*/true);
4354 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4356 llvm::Value *CalleePrefixStruct = Builder.CreateBitCast(
4357 CalleePtr, llvm::PointerType::getUnqual(PrefixStructTy));
4358 llvm::Value *CalleeSigPtr =
4359 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 0);
4360 llvm::Value *CalleeSig =
4361 Builder.CreateAlignedLoad(CalleeSigPtr, getIntAlign());
4362 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig);
4364 llvm::BasicBlock *Cont = createBasicBlock("cont");
4365 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck");
4366 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont);
4368 EmitBlock(TypeCheck);
4369 llvm::Value *CalleeRTTIPtr =
4370 Builder.CreateConstGEP2_32(PrefixStructTy, CalleePrefixStruct, 0, 1);
4371 llvm::Value *CalleeRTTI =
4372 Builder.CreateAlignedLoad(CalleeRTTIPtr, getPointerAlign());
4373 llvm::Value *CalleeRTTIMatch =
4374 Builder.CreateICmpEQ(CalleeRTTI, FTRTTIConst);
4375 llvm::Constant *StaticData[] = {
4376 EmitCheckSourceLocation(E->getLocStart()),
4377 EmitCheckTypeDescriptor(CalleeType)
4379 EmitCheck(std::make_pair(CalleeRTTIMatch, SanitizerKind::Function),
4380 SanitizerHandler::FunctionTypeMismatch, StaticData, CalleePtr);
4382 Builder.CreateBr(Cont);
4387 // If we are checking indirect calls and this call is indirect, check that the
4388 // function pointer is a member of the bit set for the function type.
4389 if (SanOpts.has(SanitizerKind::CFIICall) &&
4390 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
4391 SanitizerScope SanScope(this);
4392 EmitSanitizerStatReport(llvm::SanStat_CFI_ICall);
4394 llvm::Metadata *MD = CGM.CreateMetadataIdentifierForType(QualType(FnType, 0));
4395 llvm::Value *TypeId = llvm::MetadataAsValue::get(getLLVMContext(), MD);
4397 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4398 llvm::Value *CastedCallee = Builder.CreateBitCast(CalleePtr, Int8PtrTy);
4399 llvm::Value *TypeTest = Builder.CreateCall(
4400 CGM.getIntrinsic(llvm::Intrinsic::type_test), {CastedCallee, TypeId});
4402 auto CrossDsoTypeId = CGM.CreateCrossDsoCfiTypeId(MD);
4403 llvm::Constant *StaticData[] = {
4404 llvm::ConstantInt::get(Int8Ty, CFITCK_ICall),
4405 EmitCheckSourceLocation(E->getLocStart()),
4406 EmitCheckTypeDescriptor(QualType(FnType, 0)),
4408 if (CGM.getCodeGenOpts().SanitizeCfiCrossDso && CrossDsoTypeId) {
4409 EmitCfiSlowPathCheck(SanitizerKind::CFIICall, TypeTest, CrossDsoTypeId,
4410 CastedCallee, StaticData);
4412 EmitCheck(std::make_pair(TypeTest, SanitizerKind::CFIICall),
4413 SanitizerHandler::CFICheckFail, StaticData,
4414 {CastedCallee, llvm::UndefValue::get(IntPtrTy)});
4420 Args.add(RValue::get(Builder.CreateBitCast(Chain, CGM.VoidPtrTy)),
4421 CGM.getContext().VoidPtrTy);
4423 // C++17 requires that we evaluate arguments to a call using assignment syntax
4424 // right-to-left, and that we evaluate arguments to certain other operators
4425 // left-to-right. Note that we allow this to override the order dictated by
4426 // the calling convention on the MS ABI, which means that parameter
4427 // destruction order is not necessarily reverse construction order.
4428 // FIXME: Revisit this based on C++ committee response to unimplementability.
4429 EvaluationOrder Order = EvaluationOrder::Default;
4430 if (auto *OCE = dyn_cast<CXXOperatorCallExpr>(E)) {
4431 if (OCE->isAssignmentOp())
4432 Order = EvaluationOrder::ForceRightToLeft;
4434 switch (OCE->getOperator()) {
4436 case OO_GreaterGreater:
4441 Order = EvaluationOrder::ForceLeftToRight;
4449 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), E->arguments(),
4450 E->getDirectCallee(), /*ParamsToSkip*/ 0, Order);
4452 const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeFreeFunctionCall(
4453 Args, FnType, /*isChainCall=*/Chain);
4456 // If the expression that denotes the called function has a type
4457 // that does not include a prototype, [the default argument
4458 // promotions are performed]. If the number of arguments does not
4459 // equal the number of parameters, the behavior is undefined. If
4460 // the function is defined with a type that includes a prototype,
4461 // and either the prototype ends with an ellipsis (, ...) or the
4462 // types of the arguments after promotion are not compatible with
4463 // the types of the parameters, the behavior is undefined. If the
4464 // function is defined with a type that does not include a
4465 // prototype, and the types of the arguments after promotion are
4466 // not compatible with those of the parameters after promotion,
4467 // the behavior is undefined [except in some trivial cases].
4468 // That is, in the general case, we should assume that a call
4469 // through an unprototyped function type works like a *non-variadic*
4470 // call. The way we make this work is to cast to the exact type
4471 // of the promoted arguments.
4473 // Chain calls use this same code path to add the invisible chain parameter
4474 // to the function type.
4475 if (isa<FunctionNoProtoType>(FnType) || Chain) {
4476 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo);
4477 CalleeTy = CalleeTy->getPointerTo();
4479 llvm::Value *CalleePtr = Callee.getFunctionPointer();
4480 CalleePtr = Builder.CreateBitCast(CalleePtr, CalleeTy, "callee.knr.cast");
4481 Callee.setFunctionPointer(CalleePtr);
4484 return EmitCall(FnInfo, Callee, ReturnValue, Args);
4487 LValue CodeGenFunction::
4488 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
4489 Address BaseAddr = Address::invalid();
4490 if (E->getOpcode() == BO_PtrMemI) {
4491 BaseAddr = EmitPointerWithAlignment(E->getLHS());
4493 BaseAddr = EmitLValue(E->getLHS()).getAddress();
4496 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
4498 const MemberPointerType *MPT
4499 = E->getRHS()->getType()->getAs<MemberPointerType>();
4501 LValueBaseInfo BaseInfo;
4502 Address MemberAddr =
4503 EmitCXXMemberDataPointerAddress(E, BaseAddr, OffsetV, MPT, &BaseInfo);
4505 return MakeAddrLValue(MemberAddr, MPT->getPointeeType(), BaseInfo);
4508 /// Given the address of a temporary variable, produce an r-value of
4510 RValue CodeGenFunction::convertTempToRValue(Address addr,
4512 SourceLocation loc) {
4513 LValue lvalue = MakeAddrLValue(addr, type,
4514 LValueBaseInfo(AlignmentSource::Decl, false));
4515 switch (getEvaluationKind(type)) {
4517 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc));
4519 return lvalue.asAggregateRValue();
4521 return RValue::get(EmitLoadOfScalar(lvalue, loc));
4523 llvm_unreachable("bad evaluation kind");
4526 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) {
4527 assert(Val->getType()->isFPOrFPVectorTy());
4528 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val))
4531 llvm::MDBuilder MDHelper(getLLVMContext());
4532 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy);
4534 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node);
4538 struct LValueOrRValue {
4544 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF,
4545 const PseudoObjectExpr *E,
4547 AggValueSlot slot) {
4548 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
4550 // Find the result expression, if any.
4551 const Expr *resultExpr = E->getResultExpr();
4552 LValueOrRValue result;
4554 for (PseudoObjectExpr::const_semantics_iterator
4555 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
4556 const Expr *semantic = *i;
4558 // If this semantic expression is an opaque value, bind it
4559 // to the result of its source expression.
4560 if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
4562 // If this is the result expression, we may need to evaluate
4563 // directly into the slot.
4564 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
4566 if (ov == resultExpr && ov->isRValue() && !forLValue &&
4567 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) {
4568 CGF.EmitAggExpr(ov->getSourceExpr(), slot);
4569 LValueBaseInfo BaseInfo(AlignmentSource::Decl, false);
4570 LValue LV = CGF.MakeAddrLValue(slot.getAddress(), ov->getType(),
4572 opaqueData = OVMA::bind(CGF, ov, LV);
4573 result.RV = slot.asRValue();
4575 // Otherwise, emit as normal.
4577 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
4579 // If this is the result, also evaluate the result now.
4580 if (ov == resultExpr) {
4582 result.LV = CGF.EmitLValue(ov);
4584 result.RV = CGF.EmitAnyExpr(ov, slot);
4588 opaques.push_back(opaqueData);
4590 // Otherwise, if the expression is the result, evaluate it
4591 // and remember the result.
4592 } else if (semantic == resultExpr) {
4594 result.LV = CGF.EmitLValue(semantic);
4596 result.RV = CGF.EmitAnyExpr(semantic, slot);
4598 // Otherwise, evaluate the expression in an ignored context.
4600 CGF.EmitIgnoredExpr(semantic);
4604 // Unbind all the opaques now.
4605 for (unsigned i = 0, e = opaques.size(); i != e; ++i)
4606 opaques[i].unbind(CGF);
4611 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E,
4612 AggValueSlot slot) {
4613 return emitPseudoObjectExpr(*this, E, false, slot).RV;
4616 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) {
4617 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV;