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 //===----------------------------------------------------------------------===//
14 #include "CodeGenFunction.h"
17 #include "CGDebugInfo.h"
18 #include "CGObjCRuntime.h"
19 #include "CGRecordLayout.h"
20 #include "CodeGenModule.h"
21 #include "TargetInfo.h"
22 #include "clang/AST/ASTContext.h"
23 #include "clang/AST/DeclObjC.h"
24 #include "clang/AST/Attr.h"
25 #include "clang/Frontend/CodeGenOptions.h"
26 #include "llvm/ADT/Hashing.h"
27 #include "llvm/IR/DataLayout.h"
28 #include "llvm/IR/Intrinsics.h"
29 #include "llvm/IR/LLVMContext.h"
30 #include "llvm/IR/MDBuilder.h"
31 #include "llvm/Support/ConvertUTF.h"
33 using namespace clang;
34 using namespace CodeGen;
36 //===--------------------------------------------------------------------===//
37 // Miscellaneous Helper Methods
38 //===--------------------------------------------------------------------===//
40 llvm::Value *CodeGenFunction::EmitCastToVoidPtr(llvm::Value *value) {
41 unsigned addressSpace =
42 cast<llvm::PointerType>(value->getType())->getAddressSpace();
44 llvm::PointerType *destType = Int8PtrTy;
46 destType = llvm::Type::getInt8PtrTy(getLLVMContext(), addressSpace);
48 if (value->getType() == destType) return value;
49 return Builder.CreateBitCast(value, destType);
52 /// CreateTempAlloca - This creates a alloca and inserts it into the entry
54 llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(llvm::Type *Ty,
56 if (!Builder.isNamePreserving())
57 return new llvm::AllocaInst(Ty, nullptr, "", AllocaInsertPt);
58 return new llvm::AllocaInst(Ty, nullptr, Name, AllocaInsertPt);
61 void CodeGenFunction::InitTempAlloca(llvm::AllocaInst *Var,
63 auto *Store = new llvm::StoreInst(Init, Var);
64 llvm::BasicBlock *Block = AllocaInsertPt->getParent();
65 Block->getInstList().insertAfter(&*AllocaInsertPt, Store);
68 llvm::AllocaInst *CodeGenFunction::CreateIRTemp(QualType Ty,
70 llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertType(Ty), Name);
71 // FIXME: Should we prefer the preferred type alignment here?
72 CharUnits Align = getContext().getTypeAlignInChars(Ty);
73 Alloc->setAlignment(Align.getQuantity());
77 llvm::AllocaInst *CodeGenFunction::CreateMemTemp(QualType Ty,
79 llvm::AllocaInst *Alloc = CreateTempAlloca(ConvertTypeForMem(Ty), Name);
80 // FIXME: Should we prefer the preferred type alignment here?
81 CharUnits Align = getContext().getTypeAlignInChars(Ty);
82 Alloc->setAlignment(Align.getQuantity());
86 /// EvaluateExprAsBool - Perform the usual unary conversions on the specified
87 /// expression and compare the result against zero, returning an Int1Ty value.
88 llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
89 PGO.setCurrentStmt(E);
90 if (const MemberPointerType *MPT = E->getType()->getAs<MemberPointerType>()) {
91 llvm::Value *MemPtr = EmitScalarExpr(E);
92 return CGM.getCXXABI().EmitMemberPointerIsNotNull(*this, MemPtr, MPT);
95 QualType BoolTy = getContext().BoolTy;
96 if (!E->getType()->isAnyComplexType())
97 return EmitScalarConversion(EmitScalarExpr(E), E->getType(), BoolTy);
99 return EmitComplexToScalarConversion(EmitComplexExpr(E), E->getType(),BoolTy);
102 /// EmitIgnoredExpr - Emit code to compute the specified expression,
103 /// ignoring the result.
104 void CodeGenFunction::EmitIgnoredExpr(const Expr *E) {
106 return (void) EmitAnyExpr(E, AggValueSlot::ignored(), true);
108 // Just emit it as an l-value and drop the result.
112 /// EmitAnyExpr - Emit code to compute the specified expression which
113 /// can have any type. The result is returned as an RValue struct.
114 /// If this is an aggregate expression, AggSlot indicates where the
115 /// result should be returned.
116 RValue CodeGenFunction::EmitAnyExpr(const Expr *E,
117 AggValueSlot aggSlot,
119 switch (getEvaluationKind(E->getType())) {
121 return RValue::get(EmitScalarExpr(E, ignoreResult));
123 return RValue::getComplex(EmitComplexExpr(E, ignoreResult, ignoreResult));
125 if (!ignoreResult && aggSlot.isIgnored())
126 aggSlot = CreateAggTemp(E->getType(), "agg-temp");
127 EmitAggExpr(E, aggSlot);
128 return aggSlot.asRValue();
130 llvm_unreachable("bad evaluation kind");
133 /// EmitAnyExprToTemp - Similary to EmitAnyExpr(), however, the result will
134 /// always be accessible even if no aggregate location is provided.
135 RValue CodeGenFunction::EmitAnyExprToTemp(const Expr *E) {
136 AggValueSlot AggSlot = AggValueSlot::ignored();
138 if (hasAggregateEvaluationKind(E->getType()))
139 AggSlot = CreateAggTemp(E->getType(), "agg.tmp");
140 return EmitAnyExpr(E, AggSlot);
143 /// EmitAnyExprToMem - Evaluate an expression into a given memory
145 void CodeGenFunction::EmitAnyExprToMem(const Expr *E,
146 llvm::Value *Location,
149 // FIXME: This function should take an LValue as an argument.
150 switch (getEvaluationKind(E->getType())) {
152 EmitComplexExprIntoLValue(E,
153 MakeNaturalAlignAddrLValue(Location, E->getType()),
157 case TEK_Aggregate: {
158 CharUnits Alignment = getContext().getTypeAlignInChars(E->getType());
159 EmitAggExpr(E, AggValueSlot::forAddr(Location, Alignment, Quals,
160 AggValueSlot::IsDestructed_t(IsInit),
161 AggValueSlot::DoesNotNeedGCBarriers,
162 AggValueSlot::IsAliased_t(!IsInit)));
167 RValue RV = RValue::get(EmitScalarExpr(E, /*Ignore*/ false));
168 LValue LV = MakeAddrLValue(Location, E->getType());
169 EmitStoreThroughLValue(RV, LV);
173 llvm_unreachable("bad evaluation kind");
177 pushTemporaryCleanup(CodeGenFunction &CGF, const MaterializeTemporaryExpr *M,
178 const Expr *E, llvm::Value *ReferenceTemporary) {
179 // Objective-C++ ARC:
180 // If we are binding a reference to a temporary that has ownership, we
181 // need to perform retain/release operations on the temporary.
183 // FIXME: This should be looking at E, not M.
184 if (CGF.getLangOpts().ObjCAutoRefCount &&
185 M->getType()->isObjCLifetimeType()) {
186 QualType ObjCARCReferenceLifetimeType = M->getType();
187 switch (Qualifiers::ObjCLifetime Lifetime =
188 ObjCARCReferenceLifetimeType.getObjCLifetime()) {
189 case Qualifiers::OCL_None:
190 case Qualifiers::OCL_ExplicitNone:
191 // Carry on to normal cleanup handling.
194 case Qualifiers::OCL_Autoreleasing:
195 // Nothing to do; cleaned up by an autorelease pool.
198 case Qualifiers::OCL_Strong:
199 case Qualifiers::OCL_Weak:
200 switch (StorageDuration Duration = M->getStorageDuration()) {
202 // Note: we intentionally do not register a cleanup to release
203 // the object on program termination.
207 // FIXME: We should probably register a cleanup in this case.
211 case SD_FullExpression:
212 assert(!ObjCARCReferenceLifetimeType->isArrayType());
213 CodeGenFunction::Destroyer *Destroy;
214 CleanupKind CleanupKind;
215 if (Lifetime == Qualifiers::OCL_Strong) {
216 const ValueDecl *VD = M->getExtendingDecl();
218 VD && isa<VarDecl>(VD) && VD->hasAttr<ObjCPreciseLifetimeAttr>();
219 CleanupKind = CGF.getARCCleanupKind();
220 Destroy = Precise ? &CodeGenFunction::destroyARCStrongPrecise
221 : &CodeGenFunction::destroyARCStrongImprecise;
223 // __weak objects always get EH cleanups; otherwise, exceptions
224 // could cause really nasty crashes instead of mere leaks.
225 CleanupKind = NormalAndEHCleanup;
226 Destroy = &CodeGenFunction::destroyARCWeak;
228 if (Duration == SD_FullExpression)
229 CGF.pushDestroy(CleanupKind, ReferenceTemporary,
230 ObjCARCReferenceLifetimeType, *Destroy,
231 CleanupKind & EHCleanup);
233 CGF.pushLifetimeExtendedDestroy(CleanupKind, ReferenceTemporary,
234 ObjCARCReferenceLifetimeType,
235 *Destroy, CleanupKind & EHCleanup);
239 llvm_unreachable("temporary cannot have dynamic storage duration");
241 llvm_unreachable("unknown storage duration");
245 CXXDestructorDecl *ReferenceTemporaryDtor = nullptr;
246 if (const RecordType *RT =
247 E->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
248 // Get the destructor for the reference temporary.
249 auto *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
250 if (!ClassDecl->hasTrivialDestructor())
251 ReferenceTemporaryDtor = ClassDecl->getDestructor();
254 if (!ReferenceTemporaryDtor)
257 // Call the destructor for the temporary.
258 switch (M->getStorageDuration()) {
261 llvm::Constant *CleanupFn;
262 llvm::Constant *CleanupArg;
263 if (E->getType()->isArrayType()) {
264 CleanupFn = CodeGenFunction(CGF.CGM).generateDestroyHelper(
265 cast<llvm::Constant>(ReferenceTemporary), E->getType(),
266 CodeGenFunction::destroyCXXObject, CGF.getLangOpts().Exceptions,
267 dyn_cast_or_null<VarDecl>(M->getExtendingDecl()));
268 CleanupArg = llvm::Constant::getNullValue(CGF.Int8PtrTy);
271 CGF.CGM.GetAddrOfCXXDestructor(ReferenceTemporaryDtor, Dtor_Complete);
272 CleanupArg = cast<llvm::Constant>(ReferenceTemporary);
274 CGF.CGM.getCXXABI().registerGlobalDtor(
275 CGF, *cast<VarDecl>(M->getExtendingDecl()), CleanupFn, CleanupArg);
279 case SD_FullExpression:
280 CGF.pushDestroy(NormalAndEHCleanup, ReferenceTemporary, E->getType(),
281 CodeGenFunction::destroyCXXObject,
282 CGF.getLangOpts().Exceptions);
286 CGF.pushLifetimeExtendedDestroy(NormalAndEHCleanup,
287 ReferenceTemporary, E->getType(),
288 CodeGenFunction::destroyCXXObject,
289 CGF.getLangOpts().Exceptions);
293 llvm_unreachable("temporary cannot have dynamic storage duration");
298 createReferenceTemporary(CodeGenFunction &CGF,
299 const MaterializeTemporaryExpr *M, const Expr *Inner) {
300 switch (M->getStorageDuration()) {
301 case SD_FullExpression:
303 return CGF.CreateMemTemp(Inner->getType(), "ref.tmp");
307 return CGF.CGM.GetAddrOfGlobalTemporary(M, Inner);
310 llvm_unreachable("temporary can't have dynamic storage duration");
312 llvm_unreachable("unknown storage duration");
315 LValue CodeGenFunction::EmitMaterializeTemporaryExpr(
316 const MaterializeTemporaryExpr *M) {
317 const Expr *E = M->GetTemporaryExpr();
319 if (getLangOpts().ObjCAutoRefCount &&
320 M->getType()->isObjCLifetimeType() &&
321 M->getType().getObjCLifetime() != Qualifiers::OCL_None &&
322 M->getType().getObjCLifetime() != Qualifiers::OCL_ExplicitNone) {
323 // FIXME: Fold this into the general case below.
324 llvm::Value *Object = createReferenceTemporary(*this, M, E);
325 LValue RefTempDst = MakeAddrLValue(Object, M->getType());
327 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object)) {
328 // We should not have emitted the initializer for this temporary as a
330 assert(!Var->hasInitializer());
331 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
334 EmitScalarInit(E, M->getExtendingDecl(), RefTempDst, false);
336 pushTemporaryCleanup(*this, M, E, Object);
340 SmallVector<const Expr *, 2> CommaLHSs;
341 SmallVector<SubobjectAdjustment, 2> Adjustments;
342 E = E->skipRValueSubobjectAdjustments(CommaLHSs, Adjustments);
344 for (unsigned I = 0, N = CommaLHSs.size(); I != N; ++I)
345 EmitIgnoredExpr(CommaLHSs[I]);
347 if (const auto *opaque = dyn_cast<OpaqueValueExpr>(E)) {
348 if (opaque->getType()->isRecordType()) {
349 assert(Adjustments.empty());
350 return EmitOpaqueValueLValue(opaque);
354 // Create and initialize the reference temporary.
355 llvm::Value *Object = createReferenceTemporary(*this, M, E);
356 if (auto *Var = dyn_cast<llvm::GlobalVariable>(Object)) {
357 // If the temporary is a global and has a constant initializer, we may
358 // have already initialized it.
359 if (!Var->hasInitializer()) {
360 Var->setInitializer(CGM.EmitNullConstant(E->getType()));
361 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
364 EmitAnyExprToMem(E, Object, Qualifiers(), /*IsInit*/true);
366 pushTemporaryCleanup(*this, M, E, Object);
368 // Perform derived-to-base casts and/or field accesses, to get from the
369 // temporary object we created (and, potentially, for which we extended
370 // the lifetime) to the subobject we're binding the reference to.
371 for (unsigned I = Adjustments.size(); I != 0; --I) {
372 SubobjectAdjustment &Adjustment = Adjustments[I-1];
373 switch (Adjustment.Kind) {
374 case SubobjectAdjustment::DerivedToBaseAdjustment:
376 GetAddressOfBaseClass(Object, Adjustment.DerivedToBase.DerivedClass,
377 Adjustment.DerivedToBase.BasePath->path_begin(),
378 Adjustment.DerivedToBase.BasePath->path_end(),
379 /*NullCheckValue=*/ false);
382 case SubobjectAdjustment::FieldAdjustment: {
383 LValue LV = MakeAddrLValue(Object, E->getType());
384 LV = EmitLValueForField(LV, Adjustment.Field);
385 assert(LV.isSimple() &&
386 "materialized temporary field is not a simple lvalue");
387 Object = LV.getAddress();
391 case SubobjectAdjustment::MemberPointerAdjustment: {
392 llvm::Value *Ptr = EmitScalarExpr(Adjustment.Ptr.RHS);
393 Object = CGM.getCXXABI().EmitMemberDataPointerAddress(
394 *this, E, Object, Ptr, Adjustment.Ptr.MPT);
400 return MakeAddrLValue(Object, M->getType());
404 CodeGenFunction::EmitReferenceBindingToExpr(const Expr *E) {
405 // Emit the expression as an lvalue.
406 LValue LV = EmitLValue(E);
407 assert(LV.isSimple());
408 llvm::Value *Value = LV.getAddress();
410 if (sanitizePerformTypeCheck() && !E->getType()->isFunctionType()) {
411 // C++11 [dcl.ref]p5 (as amended by core issue 453):
412 // If a glvalue to which a reference is directly bound designates neither
413 // an existing object or function of an appropriate type nor a region of
414 // storage of suitable size and alignment to contain an object of the
415 // reference's type, the behavior is undefined.
416 QualType Ty = E->getType();
417 EmitTypeCheck(TCK_ReferenceBinding, E->getExprLoc(), Value, Ty);
420 return RValue::get(Value);
424 /// getAccessedFieldNo - Given an encoded value and a result number, return the
425 /// input field number being accessed.
426 unsigned CodeGenFunction::getAccessedFieldNo(unsigned Idx,
427 const llvm::Constant *Elts) {
428 return cast<llvm::ConstantInt>(Elts->getAggregateElement(Idx))
432 /// Emit the hash_16_bytes function from include/llvm/ADT/Hashing.h.
433 static llvm::Value *emitHash16Bytes(CGBuilderTy &Builder, llvm::Value *Low,
435 llvm::Value *KMul = Builder.getInt64(0x9ddfea08eb382d69ULL);
436 llvm::Value *K47 = Builder.getInt64(47);
437 llvm::Value *A0 = Builder.CreateMul(Builder.CreateXor(Low, High), KMul);
438 llvm::Value *A1 = Builder.CreateXor(Builder.CreateLShr(A0, K47), A0);
439 llvm::Value *B0 = Builder.CreateMul(Builder.CreateXor(High, A1), KMul);
440 llvm::Value *B1 = Builder.CreateXor(Builder.CreateLShr(B0, K47), B0);
441 return Builder.CreateMul(B1, KMul);
444 bool CodeGenFunction::sanitizePerformTypeCheck() const {
445 return SanOpts->Null | SanOpts->Alignment | SanOpts->ObjectSize |
449 void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc,
450 llvm::Value *Address,
451 QualType Ty, CharUnits Alignment) {
452 if (!sanitizePerformTypeCheck())
455 // Don't check pointers outside the default address space. The null check
456 // isn't correct, the object-size check isn't supported by LLVM, and we can't
457 // communicate the addresses to the runtime handler for the vptr check.
458 if (Address->getType()->getPointerAddressSpace())
461 SanitizerScope SanScope(this);
463 llvm::Value *Cond = nullptr;
464 llvm::BasicBlock *Done = nullptr;
466 if (SanOpts->Null || TCK == TCK_DowncastPointer) {
467 // The glvalue must not be an empty glvalue.
468 Cond = Builder.CreateICmpNE(
469 Address, llvm::Constant::getNullValue(Address->getType()));
471 if (TCK == TCK_DowncastPointer) {
472 // When performing a pointer downcast, it's OK if the value is null.
473 // Skip the remaining checks in that case.
474 Done = createBasicBlock("null");
475 llvm::BasicBlock *Rest = createBasicBlock("not.null");
476 Builder.CreateCondBr(Cond, Rest, Done);
482 if (SanOpts->ObjectSize && !Ty->isIncompleteType()) {
483 uint64_t Size = getContext().getTypeSizeInChars(Ty).getQuantity();
485 // The glvalue must refer to a large enough storage region.
486 // FIXME: If Address Sanitizer is enabled, insert dynamic instrumentation
488 // FIXME: Get object address space
489 llvm::Type *Tys[2] = { IntPtrTy, Int8PtrTy };
490 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::objectsize, Tys);
491 llvm::Value *Min = Builder.getFalse();
492 llvm::Value *CastAddr = Builder.CreateBitCast(Address, Int8PtrTy);
493 llvm::Value *LargeEnough =
494 Builder.CreateICmpUGE(Builder.CreateCall2(F, CastAddr, Min),
495 llvm::ConstantInt::get(IntPtrTy, Size));
496 Cond = Cond ? Builder.CreateAnd(Cond, LargeEnough) : LargeEnough;
499 uint64_t AlignVal = 0;
501 if (SanOpts->Alignment) {
502 AlignVal = Alignment.getQuantity();
503 if (!Ty->isIncompleteType() && !AlignVal)
504 AlignVal = getContext().getTypeAlignInChars(Ty).getQuantity();
506 // The glvalue must be suitably aligned.
509 Builder.CreateAnd(Builder.CreatePtrToInt(Address, IntPtrTy),
510 llvm::ConstantInt::get(IntPtrTy, AlignVal - 1));
511 llvm::Value *Aligned =
512 Builder.CreateICmpEQ(Align, llvm::ConstantInt::get(IntPtrTy, 0));
513 Cond = Cond ? Builder.CreateAnd(Cond, Aligned) : Aligned;
518 llvm::Constant *StaticData[] = {
519 EmitCheckSourceLocation(Loc),
520 EmitCheckTypeDescriptor(Ty),
521 llvm::ConstantInt::get(SizeTy, AlignVal),
522 llvm::ConstantInt::get(Int8Ty, TCK)
524 EmitCheck(Cond, "type_mismatch", StaticData, Address, CRK_Recoverable);
527 // If possible, check that the vptr indicates that there is a subobject of
528 // type Ty at offset zero within this object.
530 // C++11 [basic.life]p5,6:
531 // [For storage which does not refer to an object within its lifetime]
532 // The program has undefined behavior if:
533 // -- the [pointer or glvalue] is used to access a non-static data member
534 // or call a non-static member function
535 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
537 (TCK == TCK_MemberAccess || TCK == TCK_MemberCall ||
538 TCK == TCK_DowncastPointer || TCK == TCK_DowncastReference) &&
539 RD && RD->hasDefinition() && RD->isDynamicClass()) {
540 // Compute a hash of the mangled name of the type.
542 // FIXME: This is not guaranteed to be deterministic! Move to a
543 // fingerprinting mechanism once LLVM provides one. For the time
544 // being the implementation happens to be deterministic.
545 SmallString<64> MangledName;
546 llvm::raw_svector_ostream Out(MangledName);
547 CGM.getCXXABI().getMangleContext().mangleCXXRTTI(Ty.getUnqualifiedType(),
550 // Blacklist based on the mangled type.
551 if (!CGM.getSanitizerBlacklist().isBlacklistedType(Out.str())) {
552 llvm::hash_code TypeHash = hash_value(Out.str());
554 // Load the vptr, and compute hash_16_bytes(TypeHash, vptr).
555 llvm::Value *Low = llvm::ConstantInt::get(Int64Ty, TypeHash);
556 llvm::Type *VPtrTy = llvm::PointerType::get(IntPtrTy, 0);
557 llvm::Value *VPtrAddr = Builder.CreateBitCast(Address, VPtrTy);
558 llvm::Value *VPtrVal = Builder.CreateLoad(VPtrAddr);
559 llvm::Value *High = Builder.CreateZExt(VPtrVal, Int64Ty);
561 llvm::Value *Hash = emitHash16Bytes(Builder, Low, High);
562 Hash = Builder.CreateTrunc(Hash, IntPtrTy);
564 // Look the hash up in our cache.
565 const int CacheSize = 128;
566 llvm::Type *HashTable = llvm::ArrayType::get(IntPtrTy, CacheSize);
567 llvm::Value *Cache = CGM.CreateRuntimeVariable(HashTable,
568 "__ubsan_vptr_type_cache");
569 llvm::Value *Slot = Builder.CreateAnd(Hash,
570 llvm::ConstantInt::get(IntPtrTy,
572 llvm::Value *Indices[] = { Builder.getInt32(0), Slot };
573 llvm::Value *CacheVal =
574 Builder.CreateLoad(Builder.CreateInBoundsGEP(Cache, Indices));
576 // If the hash isn't in the cache, call a runtime handler to perform the
577 // hard work of checking whether the vptr is for an object of the right
578 // type. This will either fill in the cache and return, or produce a
580 llvm::Constant *StaticData[] = {
581 EmitCheckSourceLocation(Loc),
582 EmitCheckTypeDescriptor(Ty),
583 CGM.GetAddrOfRTTIDescriptor(Ty.getUnqualifiedType()),
584 llvm::ConstantInt::get(Int8Ty, TCK)
586 llvm::Value *DynamicData[] = { Address, Hash };
587 EmitCheck(Builder.CreateICmpEQ(CacheVal, Hash),
588 "dynamic_type_cache_miss", StaticData, DynamicData,
589 CRK_AlwaysRecoverable);
594 Builder.CreateBr(Done);
599 /// Determine whether this expression refers to a flexible array member in a
600 /// struct. We disable array bounds checks for such members.
601 static bool isFlexibleArrayMemberExpr(const Expr *E) {
602 // For compatibility with existing code, we treat arrays of length 0 or
603 // 1 as flexible array members.
604 const ArrayType *AT = E->getType()->castAsArrayTypeUnsafe();
605 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT)) {
606 if (CAT->getSize().ugt(1))
608 } else if (!isa<IncompleteArrayType>(AT))
611 E = E->IgnoreParens();
613 // A flexible array member must be the last member in the class.
614 if (const auto *ME = dyn_cast<MemberExpr>(E)) {
615 // FIXME: If the base type of the member expr is not FD->getParent(),
616 // this should not be treated as a flexible array member access.
617 if (const auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
618 RecordDecl::field_iterator FI(
619 DeclContext::decl_iterator(const_cast<FieldDecl *>(FD)));
620 return ++FI == FD->getParent()->field_end();
627 /// If Base is known to point to the start of an array, return the length of
628 /// that array. Return 0 if the length cannot be determined.
629 static llvm::Value *getArrayIndexingBound(
630 CodeGenFunction &CGF, const Expr *Base, QualType &IndexedType) {
631 // For the vector indexing extension, the bound is the number of elements.
632 if (const VectorType *VT = Base->getType()->getAs<VectorType>()) {
633 IndexedType = Base->getType();
634 return CGF.Builder.getInt32(VT->getNumElements());
637 Base = Base->IgnoreParens();
639 if (const auto *CE = dyn_cast<CastExpr>(Base)) {
640 if (CE->getCastKind() == CK_ArrayToPointerDecay &&
641 !isFlexibleArrayMemberExpr(CE->getSubExpr())) {
642 IndexedType = CE->getSubExpr()->getType();
643 const ArrayType *AT = IndexedType->castAsArrayTypeUnsafe();
644 if (const auto *CAT = dyn_cast<ConstantArrayType>(AT))
645 return CGF.Builder.getInt(CAT->getSize());
646 else if (const auto *VAT = dyn_cast<VariableArrayType>(AT))
647 return CGF.getVLASize(VAT).first;
654 void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base,
655 llvm::Value *Index, QualType IndexType,
657 assert(SanOpts->ArrayBounds &&
658 "should not be called unless adding bounds checks");
659 SanitizerScope SanScope(this);
661 QualType IndexedType;
662 llvm::Value *Bound = getArrayIndexingBound(*this, Base, IndexedType);
666 bool IndexSigned = IndexType->isSignedIntegerOrEnumerationType();
667 llvm::Value *IndexVal = Builder.CreateIntCast(Index, SizeTy, IndexSigned);
668 llvm::Value *BoundVal = Builder.CreateIntCast(Bound, SizeTy, false);
670 llvm::Constant *StaticData[] = {
671 EmitCheckSourceLocation(E->getExprLoc()),
672 EmitCheckTypeDescriptor(IndexedType),
673 EmitCheckTypeDescriptor(IndexType)
675 llvm::Value *Check = Accessed ? Builder.CreateICmpULT(IndexVal, BoundVal)
676 : Builder.CreateICmpULE(IndexVal, BoundVal);
677 EmitCheck(Check, "out_of_bounds", StaticData, Index, CRK_Recoverable);
681 CodeGenFunction::ComplexPairTy CodeGenFunction::
682 EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
683 bool isInc, bool isPre) {
684 ComplexPairTy InVal = EmitLoadOfComplex(LV, E->getExprLoc());
686 llvm::Value *NextVal;
687 if (isa<llvm::IntegerType>(InVal.first->getType())) {
688 uint64_t AmountVal = isInc ? 1 : -1;
689 NextVal = llvm::ConstantInt::get(InVal.first->getType(), AmountVal, true);
691 // Add the inc/dec to the real part.
692 NextVal = Builder.CreateAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
694 QualType ElemTy = E->getType()->getAs<ComplexType>()->getElementType();
695 llvm::APFloat FVal(getContext().getFloatTypeSemantics(ElemTy), 1);
698 NextVal = llvm::ConstantFP::get(getLLVMContext(), FVal);
700 // Add the inc/dec to the real part.
701 NextVal = Builder.CreateFAdd(InVal.first, NextVal, isInc ? "inc" : "dec");
704 ComplexPairTy IncVal(NextVal, InVal.second);
706 // Store the updated result through the lvalue.
707 EmitStoreOfComplex(IncVal, LV, /*init*/ false);
709 // If this is a postinc, return the value read from memory, otherwise use the
711 return isPre ? IncVal : InVal;
715 //===----------------------------------------------------------------------===//
716 // LValue Expression Emission
717 //===----------------------------------------------------------------------===//
719 RValue CodeGenFunction::GetUndefRValue(QualType Ty) {
720 if (Ty->isVoidType())
721 return RValue::get(nullptr);
723 switch (getEvaluationKind(Ty)) {
726 ConvertType(Ty->castAs<ComplexType>()->getElementType());
727 llvm::Value *U = llvm::UndefValue::get(EltTy);
728 return RValue::getComplex(std::make_pair(U, U));
731 // If this is a use of an undefined aggregate type, the aggregate must have an
732 // identifiable address. Just because the contents of the value are undefined
733 // doesn't mean that the address can't be taken and compared.
734 case TEK_Aggregate: {
735 llvm::Value *DestPtr = CreateMemTemp(Ty, "undef.agg.tmp");
736 return RValue::getAggregate(DestPtr);
740 return RValue::get(llvm::UndefValue::get(ConvertType(Ty)));
742 llvm_unreachable("bad evaluation kind");
745 RValue CodeGenFunction::EmitUnsupportedRValue(const Expr *E,
747 ErrorUnsupported(E, Name);
748 return GetUndefRValue(E->getType());
751 LValue CodeGenFunction::EmitUnsupportedLValue(const Expr *E,
753 ErrorUnsupported(E, Name);
754 llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
755 return MakeAddrLValue(llvm::UndefValue::get(Ty), E->getType());
758 LValue CodeGenFunction::EmitCheckedLValue(const Expr *E, TypeCheckKind TCK) {
760 if (SanOpts->ArrayBounds && isa<ArraySubscriptExpr>(E))
761 LV = EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E), /*Accessed*/true);
764 if (!isa<DeclRefExpr>(E) && !LV.isBitField() && LV.isSimple())
765 EmitTypeCheck(TCK, E->getExprLoc(), LV.getAddress(),
766 E->getType(), LV.getAlignment());
770 /// EmitLValue - Emit code to compute a designator that specifies the location
771 /// of the expression.
773 /// This can return one of two things: a simple address or a bitfield reference.
774 /// In either case, the LLVM Value* in the LValue structure is guaranteed to be
775 /// an LLVM pointer type.
777 /// If this returns a bitfield reference, nothing about the pointee type of the
778 /// LLVM value is known: For example, it may not be a pointer to an integer.
780 /// If this returns a normal address, and if the lvalue's C type is fixed size,
781 /// this method guarantees that the returned pointer type will point to an LLVM
782 /// type of the same size of the lvalue's type. If the lvalue has a variable
783 /// length type, this is not possible.
785 LValue CodeGenFunction::EmitLValue(const Expr *E) {
786 switch (E->getStmtClass()) {
787 default: return EmitUnsupportedLValue(E, "l-value expression");
789 case Expr::ObjCPropertyRefExprClass:
790 llvm_unreachable("cannot emit a property reference directly");
792 case Expr::ObjCSelectorExprClass:
793 return EmitObjCSelectorLValue(cast<ObjCSelectorExpr>(E));
794 case Expr::ObjCIsaExprClass:
795 return EmitObjCIsaExpr(cast<ObjCIsaExpr>(E));
796 case Expr::BinaryOperatorClass:
797 return EmitBinaryOperatorLValue(cast<BinaryOperator>(E));
798 case Expr::CompoundAssignOperatorClass:
799 if (!E->getType()->isAnyComplexType())
800 return EmitCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
801 return EmitComplexCompoundAssignmentLValue(cast<CompoundAssignOperator>(E));
802 case Expr::CallExprClass:
803 case Expr::CXXMemberCallExprClass:
804 case Expr::CXXOperatorCallExprClass:
805 case Expr::UserDefinedLiteralClass:
806 return EmitCallExprLValue(cast<CallExpr>(E));
807 case Expr::VAArgExprClass:
808 return EmitVAArgExprLValue(cast<VAArgExpr>(E));
809 case Expr::DeclRefExprClass:
810 return EmitDeclRefLValue(cast<DeclRefExpr>(E));
811 case Expr::ParenExprClass:
812 return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
813 case Expr::GenericSelectionExprClass:
814 return EmitLValue(cast<GenericSelectionExpr>(E)->getResultExpr());
815 case Expr::PredefinedExprClass:
816 return EmitPredefinedLValue(cast<PredefinedExpr>(E));
817 case Expr::StringLiteralClass:
818 return EmitStringLiteralLValue(cast<StringLiteral>(E));
819 case Expr::ObjCEncodeExprClass:
820 return EmitObjCEncodeExprLValue(cast<ObjCEncodeExpr>(E));
821 case Expr::PseudoObjectExprClass:
822 return EmitPseudoObjectLValue(cast<PseudoObjectExpr>(E));
823 case Expr::InitListExprClass:
824 return EmitInitListLValue(cast<InitListExpr>(E));
825 case Expr::CXXTemporaryObjectExprClass:
826 case Expr::CXXConstructExprClass:
827 return EmitCXXConstructLValue(cast<CXXConstructExpr>(E));
828 case Expr::CXXBindTemporaryExprClass:
829 return EmitCXXBindTemporaryLValue(cast<CXXBindTemporaryExpr>(E));
830 case Expr::CXXUuidofExprClass:
831 return EmitCXXUuidofLValue(cast<CXXUuidofExpr>(E));
832 case Expr::LambdaExprClass:
833 return EmitLambdaLValue(cast<LambdaExpr>(E));
835 case Expr::ExprWithCleanupsClass: {
836 const auto *cleanups = cast<ExprWithCleanups>(E);
837 enterFullExpression(cleanups);
838 RunCleanupsScope Scope(*this);
839 return EmitLValue(cleanups->getSubExpr());
842 case Expr::CXXDefaultArgExprClass:
843 return EmitLValue(cast<CXXDefaultArgExpr>(E)->getExpr());
844 case Expr::CXXDefaultInitExprClass: {
845 CXXDefaultInitExprScope Scope(*this);
846 return EmitLValue(cast<CXXDefaultInitExpr>(E)->getExpr());
848 case Expr::CXXTypeidExprClass:
849 return EmitCXXTypeidLValue(cast<CXXTypeidExpr>(E));
851 case Expr::ObjCMessageExprClass:
852 return EmitObjCMessageExprLValue(cast<ObjCMessageExpr>(E));
853 case Expr::ObjCIvarRefExprClass:
854 return EmitObjCIvarRefLValue(cast<ObjCIvarRefExpr>(E));
855 case Expr::StmtExprClass:
856 return EmitStmtExprLValue(cast<StmtExpr>(E));
857 case Expr::UnaryOperatorClass:
858 return EmitUnaryOpLValue(cast<UnaryOperator>(E));
859 case Expr::ArraySubscriptExprClass:
860 return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
861 case Expr::ExtVectorElementExprClass:
862 return EmitExtVectorElementExpr(cast<ExtVectorElementExpr>(E));
863 case Expr::MemberExprClass:
864 return EmitMemberExpr(cast<MemberExpr>(E));
865 case Expr::CompoundLiteralExprClass:
866 return EmitCompoundLiteralLValue(cast<CompoundLiteralExpr>(E));
867 case Expr::ConditionalOperatorClass:
868 return EmitConditionalOperatorLValue(cast<ConditionalOperator>(E));
869 case Expr::BinaryConditionalOperatorClass:
870 return EmitConditionalOperatorLValue(cast<BinaryConditionalOperator>(E));
871 case Expr::ChooseExprClass:
872 return EmitLValue(cast<ChooseExpr>(E)->getChosenSubExpr());
873 case Expr::OpaqueValueExprClass:
874 return EmitOpaqueValueLValue(cast<OpaqueValueExpr>(E));
875 case Expr::SubstNonTypeTemplateParmExprClass:
876 return EmitLValue(cast<SubstNonTypeTemplateParmExpr>(E)->getReplacement());
877 case Expr::ImplicitCastExprClass:
878 case Expr::CStyleCastExprClass:
879 case Expr::CXXFunctionalCastExprClass:
880 case Expr::CXXStaticCastExprClass:
881 case Expr::CXXDynamicCastExprClass:
882 case Expr::CXXReinterpretCastExprClass:
883 case Expr::CXXConstCastExprClass:
884 case Expr::ObjCBridgedCastExprClass:
885 return EmitCastLValue(cast<CastExpr>(E));
887 case Expr::MaterializeTemporaryExprClass:
888 return EmitMaterializeTemporaryExpr(cast<MaterializeTemporaryExpr>(E));
892 /// Given an object of the given canonical type, can we safely copy a
893 /// value out of it based on its initializer?
894 static bool isConstantEmittableObjectType(QualType type) {
895 assert(type.isCanonical());
896 assert(!type->isReferenceType());
898 // Must be const-qualified but non-volatile.
899 Qualifiers qs = type.getLocalQualifiers();
900 if (!qs.hasConst() || qs.hasVolatile()) return false;
902 // Otherwise, all object types satisfy this except C++ classes with
903 // mutable subobjects or non-trivial copy/destroy behavior.
904 if (const auto *RT = dyn_cast<RecordType>(type))
905 if (const auto *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
906 if (RD->hasMutableFields() || !RD->isTrivial())
912 /// Can we constant-emit a load of a reference to a variable of the
913 /// given type? This is different from predicates like
914 /// Decl::isUsableInConstantExpressions because we do want it to apply
915 /// in situations that don't necessarily satisfy the language's rules
916 /// for this (e.g. C++'s ODR-use rules). For example, we want to able
917 /// to do this with const float variables even if those variables
918 /// aren't marked 'constexpr'.
919 enum ConstantEmissionKind {
922 CEK_AsValueOrReference,
925 static ConstantEmissionKind checkVarTypeForConstantEmission(QualType type) {
926 type = type.getCanonicalType();
927 if (const auto *ref = dyn_cast<ReferenceType>(type)) {
928 if (isConstantEmittableObjectType(ref->getPointeeType()))
929 return CEK_AsValueOrReference;
930 return CEK_AsReferenceOnly;
932 if (isConstantEmittableObjectType(type))
933 return CEK_AsValueOnly;
937 /// Try to emit a reference to the given value without producing it as
938 /// an l-value. This is actually more than an optimization: we can't
939 /// produce an l-value for variables that we never actually captured
940 /// in a block or lambda, which means const int variables or constexpr
941 /// literals or similar.
942 CodeGenFunction::ConstantEmission
943 CodeGenFunction::tryEmitAsConstant(DeclRefExpr *refExpr) {
944 ValueDecl *value = refExpr->getDecl();
946 // The value needs to be an enum constant or a constant variable.
947 ConstantEmissionKind CEK;
948 if (isa<ParmVarDecl>(value)) {
950 } else if (auto *var = dyn_cast<VarDecl>(value)) {
951 CEK = checkVarTypeForConstantEmission(var->getType());
952 } else if (isa<EnumConstantDecl>(value)) {
953 CEK = CEK_AsValueOnly;
957 if (CEK == CEK_None) return ConstantEmission();
959 Expr::EvalResult result;
960 bool resultIsReference;
963 // It's best to evaluate all the way as an r-value if that's permitted.
964 if (CEK != CEK_AsReferenceOnly &&
965 refExpr->EvaluateAsRValue(result, getContext())) {
966 resultIsReference = false;
967 resultType = refExpr->getType();
969 // Otherwise, try to evaluate as an l-value.
970 } else if (CEK != CEK_AsValueOnly &&
971 refExpr->EvaluateAsLValue(result, getContext())) {
972 resultIsReference = true;
973 resultType = value->getType();
977 return ConstantEmission();
980 // In any case, if the initializer has side-effects, abandon ship.
981 if (result.HasSideEffects)
982 return ConstantEmission();
984 // Emit as a constant.
985 llvm::Constant *C = CGM.EmitConstantValue(result.Val, resultType, this);
987 // Make sure we emit a debug reference to the global variable.
988 // This should probably fire even for
989 if (isa<VarDecl>(value)) {
990 if (!getContext().DeclMustBeEmitted(cast<VarDecl>(value)))
991 EmitDeclRefExprDbgValue(refExpr, C);
993 assert(isa<EnumConstantDecl>(value));
994 EmitDeclRefExprDbgValue(refExpr, C);
997 // If we emitted a reference constant, we need to dereference that.
998 if (resultIsReference)
999 return ConstantEmission::forReference(C);
1001 return ConstantEmission::forValue(C);
1004 llvm::Value *CodeGenFunction::EmitLoadOfScalar(LValue lvalue,
1005 SourceLocation Loc) {
1006 return EmitLoadOfScalar(lvalue.getAddress(), lvalue.isVolatile(),
1007 lvalue.getAlignment().getQuantity(),
1008 lvalue.getType(), Loc, lvalue.getTBAAInfo(),
1009 lvalue.getTBAABaseType(), lvalue.getTBAAOffset());
1012 static bool hasBooleanRepresentation(QualType Ty) {
1013 if (Ty->isBooleanType())
1016 if (const EnumType *ET = Ty->getAs<EnumType>())
1017 return ET->getDecl()->getIntegerType()->isBooleanType();
1019 if (const AtomicType *AT = Ty->getAs<AtomicType>())
1020 return hasBooleanRepresentation(AT->getValueType());
1025 static bool getRangeForType(CodeGenFunction &CGF, QualType Ty,
1026 llvm::APInt &Min, llvm::APInt &End,
1028 const EnumType *ET = Ty->getAs<EnumType>();
1029 bool IsRegularCPlusPlusEnum = CGF.getLangOpts().CPlusPlus && StrictEnums &&
1030 ET && !ET->getDecl()->isFixed();
1031 bool IsBool = hasBooleanRepresentation(Ty);
1032 if (!IsBool && !IsRegularCPlusPlusEnum)
1036 Min = llvm::APInt(CGF.getContext().getTypeSize(Ty), 0);
1037 End = llvm::APInt(CGF.getContext().getTypeSize(Ty), 2);
1039 const EnumDecl *ED = ET->getDecl();
1040 llvm::Type *LTy = CGF.ConvertTypeForMem(ED->getIntegerType());
1041 unsigned Bitwidth = LTy->getScalarSizeInBits();
1042 unsigned NumNegativeBits = ED->getNumNegativeBits();
1043 unsigned NumPositiveBits = ED->getNumPositiveBits();
1045 if (NumNegativeBits) {
1046 unsigned NumBits = std::max(NumNegativeBits, NumPositiveBits + 1);
1047 assert(NumBits <= Bitwidth);
1048 End = llvm::APInt(Bitwidth, 1) << (NumBits - 1);
1051 assert(NumPositiveBits <= Bitwidth);
1052 End = llvm::APInt(Bitwidth, 1) << NumPositiveBits;
1053 Min = llvm::APInt(Bitwidth, 0);
1059 llvm::MDNode *CodeGenFunction::getRangeForLoadFromType(QualType Ty) {
1060 llvm::APInt Min, End;
1061 if (!getRangeForType(*this, Ty, Min, End,
1062 CGM.getCodeGenOpts().StrictEnums))
1065 llvm::MDBuilder MDHelper(getLLVMContext());
1066 return MDHelper.createRange(Min, End);
1069 llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile,
1070 unsigned Alignment, QualType Ty,
1072 llvm::MDNode *TBAAInfo,
1073 QualType TBAABaseType,
1074 uint64_t TBAAOffset) {
1075 // For better performance, handle vector loads differently.
1076 if (Ty->isVectorType()) {
1078 const llvm::Type *EltTy =
1079 cast<llvm::PointerType>(Addr->getType())->getElementType();
1081 const auto *VTy = cast<llvm::VectorType>(EltTy);
1083 // Handle vectors of size 3, like size 4 for better performance.
1084 if (VTy->getNumElements() == 3) {
1086 // Bitcast to vec4 type.
1087 llvm::VectorType *vec4Ty = llvm::VectorType::get(VTy->getElementType(),
1089 llvm::PointerType *ptVec4Ty =
1090 llvm::PointerType::get(vec4Ty,
1091 (cast<llvm::PointerType>(
1092 Addr->getType()))->getAddressSpace());
1093 llvm::Value *Cast = Builder.CreateBitCast(Addr, ptVec4Ty,
1096 llvm::Value *LoadVal = Builder.CreateLoad(Cast, Volatile, "loadVec4");
1098 // Shuffle vector to get vec3.
1099 llvm::Constant *Mask[] = {
1100 llvm::ConstantInt::get(llvm::Type::getInt32Ty(getLLVMContext()), 0),
1101 llvm::ConstantInt::get(llvm::Type::getInt32Ty(getLLVMContext()), 1),
1102 llvm::ConstantInt::get(llvm::Type::getInt32Ty(getLLVMContext()), 2)
1105 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1106 V = Builder.CreateShuffleVector(LoadVal,
1107 llvm::UndefValue::get(vec4Ty),
1108 MaskV, "extractVec");
1109 return EmitFromMemory(V, Ty);
1113 // Atomic operations have to be done on integral types.
1114 if (Ty->isAtomicType()) {
1115 LValue lvalue = LValue::MakeAddr(Addr, Ty,
1116 CharUnits::fromQuantity(Alignment),
1117 getContext(), TBAAInfo);
1118 return EmitAtomicLoad(lvalue, Loc).getScalarVal();
1121 llvm::LoadInst *Load = Builder.CreateLoad(Addr);
1123 Load->setVolatile(true);
1125 Load->setAlignment(Alignment);
1127 llvm::MDNode *TBAAPath = CGM.getTBAAStructTagInfo(TBAABaseType, TBAAInfo,
1130 CGM.DecorateInstruction(Load, TBAAPath, false/*ConvertTypeToTag*/);
1133 if ((SanOpts->Bool && hasBooleanRepresentation(Ty)) ||
1134 (SanOpts->Enum && Ty->getAs<EnumType>())) {
1135 SanitizerScope SanScope(this);
1136 llvm::APInt Min, End;
1137 if (getRangeForType(*this, Ty, Min, End, true)) {
1141 Check = Builder.CreateICmpULE(
1142 Load, llvm::ConstantInt::get(getLLVMContext(), End));
1144 llvm::Value *Upper = Builder.CreateICmpSLE(
1145 Load, llvm::ConstantInt::get(getLLVMContext(), End));
1146 llvm::Value *Lower = Builder.CreateICmpSGE(
1147 Load, llvm::ConstantInt::get(getLLVMContext(), Min));
1148 Check = Builder.CreateAnd(Upper, Lower);
1150 llvm::Constant *StaticArgs[] = {
1151 EmitCheckSourceLocation(Loc),
1152 EmitCheckTypeDescriptor(Ty)
1154 EmitCheck(Check, "load_invalid_value", StaticArgs, EmitCheckValue(Load),
1157 } else if (CGM.getCodeGenOpts().OptimizationLevel > 0)
1158 if (llvm::MDNode *RangeInfo = getRangeForLoadFromType(Ty))
1159 Load->setMetadata(llvm::LLVMContext::MD_range, RangeInfo);
1161 return EmitFromMemory(Load, Ty);
1164 llvm::Value *CodeGenFunction::EmitToMemory(llvm::Value *Value, QualType Ty) {
1165 // Bool has a different representation in memory than in registers.
1166 if (hasBooleanRepresentation(Ty)) {
1167 // This should really always be an i1, but sometimes it's already
1168 // an i8, and it's awkward to track those cases down.
1169 if (Value->getType()->isIntegerTy(1))
1170 return Builder.CreateZExt(Value, ConvertTypeForMem(Ty), "frombool");
1171 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1172 "wrong value rep of bool");
1178 llvm::Value *CodeGenFunction::EmitFromMemory(llvm::Value *Value, QualType Ty) {
1179 // Bool has a different representation in memory than in registers.
1180 if (hasBooleanRepresentation(Ty)) {
1181 assert(Value->getType()->isIntegerTy(getContext().getTypeSize(Ty)) &&
1182 "wrong value rep of bool");
1183 return Builder.CreateTrunc(Value, Builder.getInt1Ty(), "tobool");
1189 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *Value, llvm::Value *Addr,
1190 bool Volatile, unsigned Alignment,
1191 QualType Ty, llvm::MDNode *TBAAInfo,
1192 bool isInit, QualType TBAABaseType,
1193 uint64_t TBAAOffset) {
1195 // Handle vectors differently to get better performance.
1196 if (Ty->isVectorType()) {
1197 llvm::Type *SrcTy = Value->getType();
1198 auto *VecTy = cast<llvm::VectorType>(SrcTy);
1199 // Handle vec3 special.
1200 if (VecTy->getNumElements() == 3) {
1201 llvm::LLVMContext &VMContext = getLLVMContext();
1203 // Our source is a vec3, do a shuffle vector to make it a vec4.
1204 SmallVector<llvm::Constant*, 4> Mask;
1205 Mask.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext),
1207 Mask.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext),
1209 Mask.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext),
1211 Mask.push_back(llvm::UndefValue::get(llvm::Type::getInt32Ty(VMContext)));
1213 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1214 Value = Builder.CreateShuffleVector(Value,
1215 llvm::UndefValue::get(VecTy),
1216 MaskV, "extractVec");
1217 SrcTy = llvm::VectorType::get(VecTy->getElementType(), 4);
1219 auto *DstPtr = cast<llvm::PointerType>(Addr->getType());
1220 if (DstPtr->getElementType() != SrcTy) {
1222 llvm::PointerType::get(SrcTy, DstPtr->getAddressSpace());
1223 Addr = Builder.CreateBitCast(Addr, MemTy, "storetmp");
1227 Value = EmitToMemory(Value, Ty);
1229 if (Ty->isAtomicType()) {
1230 EmitAtomicStore(RValue::get(Value),
1231 LValue::MakeAddr(Addr, Ty,
1232 CharUnits::fromQuantity(Alignment),
1233 getContext(), TBAAInfo),
1238 llvm::StoreInst *Store = Builder.CreateStore(Value, Addr, Volatile);
1240 Store->setAlignment(Alignment);
1242 llvm::MDNode *TBAAPath = CGM.getTBAAStructTagInfo(TBAABaseType, TBAAInfo,
1245 CGM.DecorateInstruction(Store, TBAAPath, false/*ConvertTypeToTag*/);
1249 void CodeGenFunction::EmitStoreOfScalar(llvm::Value *value, LValue lvalue,
1251 EmitStoreOfScalar(value, lvalue.getAddress(), lvalue.isVolatile(),
1252 lvalue.getAlignment().getQuantity(), lvalue.getType(),
1253 lvalue.getTBAAInfo(), isInit, lvalue.getTBAABaseType(),
1254 lvalue.getTBAAOffset());
1257 /// EmitLoadOfLValue - Given an expression that represents a value lvalue, this
1258 /// method emits the address of the lvalue, then loads the result as an rvalue,
1259 /// returning the rvalue.
1260 RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, SourceLocation Loc) {
1261 if (LV.isObjCWeak()) {
1262 // load of a __weak object.
1263 llvm::Value *AddrWeakObj = LV.getAddress();
1264 return RValue::get(CGM.getObjCRuntime().EmitObjCWeakRead(*this,
1267 if (LV.getQuals().getObjCLifetime() == Qualifiers::OCL_Weak) {
1268 llvm::Value *Object = EmitARCLoadWeakRetained(LV.getAddress());
1269 Object = EmitObjCConsumeObject(LV.getType(), Object);
1270 return RValue::get(Object);
1273 if (LV.isSimple()) {
1274 assert(!LV.getType()->isFunctionType());
1276 // Everything needs a load.
1277 return RValue::get(EmitLoadOfScalar(LV, Loc));
1280 if (LV.isVectorElt()) {
1281 llvm::LoadInst *Load = Builder.CreateLoad(LV.getVectorAddr(),
1282 LV.isVolatileQualified());
1283 Load->setAlignment(LV.getAlignment().getQuantity());
1284 return RValue::get(Builder.CreateExtractElement(Load, LV.getVectorIdx(),
1288 // If this is a reference to a subset of the elements of a vector, either
1289 // shuffle the input or extract/insert them as appropriate.
1290 if (LV.isExtVectorElt())
1291 return EmitLoadOfExtVectorElementLValue(LV);
1293 // Global Register variables always invoke intrinsics
1294 if (LV.isGlobalReg())
1295 return EmitLoadOfGlobalRegLValue(LV);
1297 assert(LV.isBitField() && "Unknown LValue type!");
1298 return EmitLoadOfBitfieldLValue(LV);
1301 RValue CodeGenFunction::EmitLoadOfBitfieldLValue(LValue LV) {
1302 const CGBitFieldInfo &Info = LV.getBitFieldInfo();
1304 // Get the output type.
1305 llvm::Type *ResLTy = ConvertType(LV.getType());
1307 llvm::Value *Ptr = LV.getBitFieldAddr();
1308 llvm::Value *Val = Builder.CreateLoad(Ptr, LV.isVolatileQualified(),
1310 cast<llvm::LoadInst>(Val)->setAlignment(Info.StorageAlignment);
1312 if (Info.IsSigned) {
1313 assert(static_cast<unsigned>(Info.Offset + Info.Size) <= Info.StorageSize);
1314 unsigned HighBits = Info.StorageSize - Info.Offset - Info.Size;
1316 Val = Builder.CreateShl(Val, HighBits, "bf.shl");
1317 if (Info.Offset + HighBits)
1318 Val = Builder.CreateAShr(Val, Info.Offset + HighBits, "bf.ashr");
1321 Val = Builder.CreateLShr(Val, Info.Offset, "bf.lshr");
1322 if (static_cast<unsigned>(Info.Offset) + Info.Size < Info.StorageSize)
1323 Val = Builder.CreateAnd(Val, llvm::APInt::getLowBitsSet(Info.StorageSize,
1327 Val = Builder.CreateIntCast(Val, ResLTy, Info.IsSigned, "bf.cast");
1329 return RValue::get(Val);
1332 // If this is a reference to a subset of the elements of a vector, create an
1333 // appropriate shufflevector.
1334 RValue CodeGenFunction::EmitLoadOfExtVectorElementLValue(LValue LV) {
1335 llvm::LoadInst *Load = Builder.CreateLoad(LV.getExtVectorAddr(),
1336 LV.isVolatileQualified());
1337 Load->setAlignment(LV.getAlignment().getQuantity());
1338 llvm::Value *Vec = Load;
1340 const llvm::Constant *Elts = LV.getExtVectorElts();
1342 // If the result of the expression is a non-vector type, we must be extracting
1343 // a single element. Just codegen as an extractelement.
1344 const VectorType *ExprVT = LV.getType()->getAs<VectorType>();
1346 unsigned InIdx = getAccessedFieldNo(0, Elts);
1347 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1348 return RValue::get(Builder.CreateExtractElement(Vec, Elt));
1351 // Always use shuffle vector to try to retain the original program structure
1352 unsigned NumResultElts = ExprVT->getNumElements();
1354 SmallVector<llvm::Constant*, 4> Mask;
1355 for (unsigned i = 0; i != NumResultElts; ++i)
1356 Mask.push_back(Builder.getInt32(getAccessedFieldNo(i, Elts)));
1358 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1359 Vec = Builder.CreateShuffleVector(Vec, llvm::UndefValue::get(Vec->getType()),
1361 return RValue::get(Vec);
1364 /// @brief Load of global gamed gegisters are always calls to intrinsics.
1365 RValue CodeGenFunction::EmitLoadOfGlobalRegLValue(LValue LV) {
1366 assert((LV.getType()->isIntegerType() || LV.getType()->isPointerType()) &&
1367 "Bad type for register variable");
1368 llvm::MDNode *RegName = dyn_cast<llvm::MDNode>(LV.getGlobalReg());
1369 assert(RegName && "Register LValue is not metadata");
1371 // We accept integer and pointer types only
1372 llvm::Type *OrigTy = CGM.getTypes().ConvertType(LV.getType());
1373 llvm::Type *Ty = OrigTy;
1374 if (OrigTy->isPointerTy())
1375 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
1376 llvm::Type *Types[] = { Ty };
1378 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::read_register, Types);
1379 llvm::Value *Call = Builder.CreateCall(F, RegName);
1380 if (OrigTy->isPointerTy())
1381 Call = Builder.CreateIntToPtr(Call, OrigTy);
1382 return RValue::get(Call);
1386 /// EmitStoreThroughLValue - Store the specified rvalue into the specified
1387 /// lvalue, where both are guaranteed to the have the same type, and that type
1389 void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
1391 if (!Dst.isSimple()) {
1392 if (Dst.isVectorElt()) {
1393 // Read/modify/write the vector, inserting the new element.
1394 llvm::LoadInst *Load = Builder.CreateLoad(Dst.getVectorAddr(),
1395 Dst.isVolatileQualified());
1396 Load->setAlignment(Dst.getAlignment().getQuantity());
1397 llvm::Value *Vec = Load;
1398 Vec = Builder.CreateInsertElement(Vec, Src.getScalarVal(),
1399 Dst.getVectorIdx(), "vecins");
1400 llvm::StoreInst *Store = Builder.CreateStore(Vec, Dst.getVectorAddr(),
1401 Dst.isVolatileQualified());
1402 Store->setAlignment(Dst.getAlignment().getQuantity());
1406 // If this is an update of extended vector elements, insert them as
1408 if (Dst.isExtVectorElt())
1409 return EmitStoreThroughExtVectorComponentLValue(Src, Dst);
1411 if (Dst.isGlobalReg())
1412 return EmitStoreThroughGlobalRegLValue(Src, Dst);
1414 assert(Dst.isBitField() && "Unknown LValue type");
1415 return EmitStoreThroughBitfieldLValue(Src, Dst);
1418 // There's special magic for assigning into an ARC-qualified l-value.
1419 if (Qualifiers::ObjCLifetime Lifetime = Dst.getQuals().getObjCLifetime()) {
1421 case Qualifiers::OCL_None:
1422 llvm_unreachable("present but none");
1424 case Qualifiers::OCL_ExplicitNone:
1428 case Qualifiers::OCL_Strong:
1429 EmitARCStoreStrong(Dst, Src.getScalarVal(), /*ignore*/ true);
1432 case Qualifiers::OCL_Weak:
1433 EmitARCStoreWeak(Dst.getAddress(), Src.getScalarVal(), /*ignore*/ true);
1436 case Qualifiers::OCL_Autoreleasing:
1437 Src = RValue::get(EmitObjCExtendObjectLifetime(Dst.getType(),
1438 Src.getScalarVal()));
1439 // fall into the normal path
1444 if (Dst.isObjCWeak() && !Dst.isNonGC()) {
1445 // load of a __weak object.
1446 llvm::Value *LvalueDst = Dst.getAddress();
1447 llvm::Value *src = Src.getScalarVal();
1448 CGM.getObjCRuntime().EmitObjCWeakAssign(*this, src, LvalueDst);
1452 if (Dst.isObjCStrong() && !Dst.isNonGC()) {
1453 // load of a __strong object.
1454 llvm::Value *LvalueDst = Dst.getAddress();
1455 llvm::Value *src = Src.getScalarVal();
1456 if (Dst.isObjCIvar()) {
1457 assert(Dst.getBaseIvarExp() && "BaseIvarExp is NULL");
1458 llvm::Type *ResultType = ConvertType(getContext().LongTy);
1459 llvm::Value *RHS = EmitScalarExpr(Dst.getBaseIvarExp());
1460 llvm::Value *dst = RHS;
1461 RHS = Builder.CreatePtrToInt(RHS, ResultType, "sub.ptr.rhs.cast");
1463 Builder.CreatePtrToInt(LvalueDst, ResultType, "sub.ptr.lhs.cast");
1464 llvm::Value *BytesBetween = Builder.CreateSub(LHS, RHS, "ivar.offset");
1465 CGM.getObjCRuntime().EmitObjCIvarAssign(*this, src, dst,
1467 } else if (Dst.isGlobalObjCRef()) {
1468 CGM.getObjCRuntime().EmitObjCGlobalAssign(*this, src, LvalueDst,
1469 Dst.isThreadLocalRef());
1472 CGM.getObjCRuntime().EmitObjCStrongCastAssign(*this, src, LvalueDst);
1476 assert(Src.isScalar() && "Can't emit an agg store with this method");
1477 EmitStoreOfScalar(Src.getScalarVal(), Dst, isInit);
1480 void CodeGenFunction::EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
1481 llvm::Value **Result) {
1482 const CGBitFieldInfo &Info = Dst.getBitFieldInfo();
1483 llvm::Type *ResLTy = ConvertTypeForMem(Dst.getType());
1484 llvm::Value *Ptr = Dst.getBitFieldAddr();
1486 // Get the source value, truncated to the width of the bit-field.
1487 llvm::Value *SrcVal = Src.getScalarVal();
1489 // Cast the source to the storage type and shift it into place.
1490 SrcVal = Builder.CreateIntCast(SrcVal,
1491 Ptr->getType()->getPointerElementType(),
1492 /*IsSigned=*/false);
1493 llvm::Value *MaskedVal = SrcVal;
1495 // See if there are other bits in the bitfield's storage we'll need to load
1496 // and mask together with source before storing.
1497 if (Info.StorageSize != Info.Size) {
1498 assert(Info.StorageSize > Info.Size && "Invalid bitfield size.");
1499 llvm::Value *Val = Builder.CreateLoad(Ptr, Dst.isVolatileQualified(),
1501 cast<llvm::LoadInst>(Val)->setAlignment(Info.StorageAlignment);
1503 // Mask the source value as needed.
1504 if (!hasBooleanRepresentation(Dst.getType()))
1505 SrcVal = Builder.CreateAnd(SrcVal,
1506 llvm::APInt::getLowBitsSet(Info.StorageSize,
1511 SrcVal = Builder.CreateShl(SrcVal, Info.Offset, "bf.shl");
1513 // Mask out the original value.
1514 Val = Builder.CreateAnd(Val,
1515 ~llvm::APInt::getBitsSet(Info.StorageSize,
1517 Info.Offset + Info.Size),
1520 // Or together the unchanged values and the source value.
1521 SrcVal = Builder.CreateOr(Val, SrcVal, "bf.set");
1523 assert(Info.Offset == 0);
1526 // Write the new value back out.
1527 llvm::StoreInst *Store = Builder.CreateStore(SrcVal, Ptr,
1528 Dst.isVolatileQualified());
1529 Store->setAlignment(Info.StorageAlignment);
1531 // Return the new value of the bit-field, if requested.
1533 llvm::Value *ResultVal = MaskedVal;
1535 // Sign extend the value if needed.
1536 if (Info.IsSigned) {
1537 assert(Info.Size <= Info.StorageSize);
1538 unsigned HighBits = Info.StorageSize - Info.Size;
1540 ResultVal = Builder.CreateShl(ResultVal, HighBits, "bf.result.shl");
1541 ResultVal = Builder.CreateAShr(ResultVal, HighBits, "bf.result.ashr");
1545 ResultVal = Builder.CreateIntCast(ResultVal, ResLTy, Info.IsSigned,
1547 *Result = EmitFromMemory(ResultVal, Dst.getType());
1551 void CodeGenFunction::EmitStoreThroughExtVectorComponentLValue(RValue Src,
1553 // This access turns into a read/modify/write of the vector. Load the input
1555 llvm::LoadInst *Load = Builder.CreateLoad(Dst.getExtVectorAddr(),
1556 Dst.isVolatileQualified());
1557 Load->setAlignment(Dst.getAlignment().getQuantity());
1558 llvm::Value *Vec = Load;
1559 const llvm::Constant *Elts = Dst.getExtVectorElts();
1561 llvm::Value *SrcVal = Src.getScalarVal();
1563 if (const VectorType *VTy = Dst.getType()->getAs<VectorType>()) {
1564 unsigned NumSrcElts = VTy->getNumElements();
1565 unsigned NumDstElts =
1566 cast<llvm::VectorType>(Vec->getType())->getNumElements();
1567 if (NumDstElts == NumSrcElts) {
1568 // Use shuffle vector is the src and destination are the same number of
1569 // elements and restore the vector mask since it is on the side it will be
1571 SmallVector<llvm::Constant*, 4> Mask(NumDstElts);
1572 for (unsigned i = 0; i != NumSrcElts; ++i)
1573 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i);
1575 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1576 Vec = Builder.CreateShuffleVector(SrcVal,
1577 llvm::UndefValue::get(Vec->getType()),
1579 } else if (NumDstElts > NumSrcElts) {
1580 // Extended the source vector to the same length and then shuffle it
1581 // into the destination.
1582 // FIXME: since we're shuffling with undef, can we just use the indices
1583 // into that? This could be simpler.
1584 SmallVector<llvm::Constant*, 4> ExtMask;
1585 for (unsigned i = 0; i != NumSrcElts; ++i)
1586 ExtMask.push_back(Builder.getInt32(i));
1587 ExtMask.resize(NumDstElts, llvm::UndefValue::get(Int32Ty));
1588 llvm::Value *ExtMaskV = llvm::ConstantVector::get(ExtMask);
1589 llvm::Value *ExtSrcVal =
1590 Builder.CreateShuffleVector(SrcVal,
1591 llvm::UndefValue::get(SrcVal->getType()),
1594 SmallVector<llvm::Constant*, 4> Mask;
1595 for (unsigned i = 0; i != NumDstElts; ++i)
1596 Mask.push_back(Builder.getInt32(i));
1598 // When the vector size is odd and .odd or .hi is used, the last element
1599 // of the Elts constant array will be one past the size of the vector.
1600 // Ignore the last element here, if it is greater than the mask size.
1601 if (getAccessedFieldNo(NumSrcElts - 1, Elts) == Mask.size())
1604 // modify when what gets shuffled in
1605 for (unsigned i = 0; i != NumSrcElts; ++i)
1606 Mask[getAccessedFieldNo(i, Elts)] = Builder.getInt32(i+NumDstElts);
1607 llvm::Value *MaskV = llvm::ConstantVector::get(Mask);
1608 Vec = Builder.CreateShuffleVector(Vec, ExtSrcVal, MaskV);
1610 // We should never shorten the vector
1611 llvm_unreachable("unexpected shorten vector length");
1614 // If the Src is a scalar (not a vector) it must be updating one element.
1615 unsigned InIdx = getAccessedFieldNo(0, Elts);
1616 llvm::Value *Elt = llvm::ConstantInt::get(SizeTy, InIdx);
1617 Vec = Builder.CreateInsertElement(Vec, SrcVal, Elt);
1620 llvm::StoreInst *Store = Builder.CreateStore(Vec, Dst.getExtVectorAddr(),
1621 Dst.isVolatileQualified());
1622 Store->setAlignment(Dst.getAlignment().getQuantity());
1625 /// @brief Store of global named registers are always calls to intrinsics.
1626 void CodeGenFunction::EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst) {
1627 assert((Dst.getType()->isIntegerType() || Dst.getType()->isPointerType()) &&
1628 "Bad type for register variable");
1629 llvm::MDNode *RegName = dyn_cast<llvm::MDNode>(Dst.getGlobalReg());
1630 assert(RegName && "Register LValue is not metadata");
1632 // We accept integer and pointer types only
1633 llvm::Type *OrigTy = CGM.getTypes().ConvertType(Dst.getType());
1634 llvm::Type *Ty = OrigTy;
1635 if (OrigTy->isPointerTy())
1636 Ty = CGM.getTypes().getDataLayout().getIntPtrType(OrigTy);
1637 llvm::Type *Types[] = { Ty };
1639 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::write_register, Types);
1640 llvm::Value *Value = Src.getScalarVal();
1641 if (OrigTy->isPointerTy())
1642 Value = Builder.CreatePtrToInt(Value, Ty);
1643 Builder.CreateCall2(F, RegName, Value);
1646 // setObjCGCLValueClass - sets class of the lvalue for the purpose of
1647 // generating write-barries API. It is currently a global, ivar,
1649 static void setObjCGCLValueClass(const ASTContext &Ctx, const Expr *E,
1651 bool IsMemberAccess=false) {
1652 if (Ctx.getLangOpts().getGC() == LangOptions::NonGC)
1655 if (isa<ObjCIvarRefExpr>(E)) {
1656 QualType ExpTy = E->getType();
1657 if (IsMemberAccess && ExpTy->isPointerType()) {
1658 // If ivar is a structure pointer, assigning to field of
1659 // this struct follows gcc's behavior and makes it a non-ivar
1660 // writer-barrier conservatively.
1661 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
1662 if (ExpTy->isRecordType()) {
1663 LV.setObjCIvar(false);
1667 LV.setObjCIvar(true);
1668 auto *Exp = cast<ObjCIvarRefExpr>(const_cast<Expr *>(E));
1669 LV.setBaseIvarExp(Exp->getBase());
1670 LV.setObjCArray(E->getType()->isArrayType());
1674 if (const auto *Exp = dyn_cast<DeclRefExpr>(E)) {
1675 if (const auto *VD = dyn_cast<VarDecl>(Exp->getDecl())) {
1676 if (VD->hasGlobalStorage()) {
1677 LV.setGlobalObjCRef(true);
1678 LV.setThreadLocalRef(VD->getTLSKind() != VarDecl::TLS_None);
1681 LV.setObjCArray(E->getType()->isArrayType());
1685 if (const auto *Exp = dyn_cast<UnaryOperator>(E)) {
1686 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1690 if (const auto *Exp = dyn_cast<ParenExpr>(E)) {
1691 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1692 if (LV.isObjCIvar()) {
1693 // If cast is to a structure pointer, follow gcc's behavior and make it
1694 // a non-ivar write-barrier.
1695 QualType ExpTy = E->getType();
1696 if (ExpTy->isPointerType())
1697 ExpTy = ExpTy->getAs<PointerType>()->getPointeeType();
1698 if (ExpTy->isRecordType())
1699 LV.setObjCIvar(false);
1704 if (const auto *Exp = dyn_cast<GenericSelectionExpr>(E)) {
1705 setObjCGCLValueClass(Ctx, Exp->getResultExpr(), LV);
1709 if (const auto *Exp = dyn_cast<ImplicitCastExpr>(E)) {
1710 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1714 if (const auto *Exp = dyn_cast<CStyleCastExpr>(E)) {
1715 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1719 if (const auto *Exp = dyn_cast<ObjCBridgedCastExpr>(E)) {
1720 setObjCGCLValueClass(Ctx, Exp->getSubExpr(), LV, IsMemberAccess);
1724 if (const auto *Exp = dyn_cast<ArraySubscriptExpr>(E)) {
1725 setObjCGCLValueClass(Ctx, Exp->getBase(), LV);
1726 if (LV.isObjCIvar() && !LV.isObjCArray())
1727 // Using array syntax to assigning to what an ivar points to is not
1728 // same as assigning to the ivar itself. {id *Names;} Names[i] = 0;
1729 LV.setObjCIvar(false);
1730 else if (LV.isGlobalObjCRef() && !LV.isObjCArray())
1731 // Using array syntax to assigning to what global points to is not
1732 // same as assigning to the global itself. {id *G;} G[i] = 0;
1733 LV.setGlobalObjCRef(false);
1737 if (const auto *Exp = dyn_cast<MemberExpr>(E)) {
1738 setObjCGCLValueClass(Ctx, Exp->getBase(), LV, true);
1739 // We don't know if member is an 'ivar', but this flag is looked at
1740 // only in the context of LV.isObjCIvar().
1741 LV.setObjCArray(E->getType()->isArrayType());
1746 static llvm::Value *
1747 EmitBitCastOfLValueToProperType(CodeGenFunction &CGF,
1748 llvm::Value *V, llvm::Type *IRType,
1749 StringRef Name = StringRef()) {
1750 unsigned AS = cast<llvm::PointerType>(V->getType())->getAddressSpace();
1751 return CGF.Builder.CreateBitCast(V, IRType->getPointerTo(AS), Name);
1754 static LValue EmitGlobalVarDeclLValue(CodeGenFunction &CGF,
1755 const Expr *E, const VarDecl *VD) {
1756 QualType T = E->getType();
1758 // If it's thread_local, emit a call to its wrapper function instead.
1759 if (VD->getTLSKind() == VarDecl::TLS_Dynamic)
1760 return CGF.CGM.getCXXABI().EmitThreadLocalVarDeclLValue(CGF, VD, T);
1762 llvm::Value *V = CGF.CGM.GetAddrOfGlobalVar(VD);
1763 llvm::Type *RealVarTy = CGF.getTypes().ConvertTypeForMem(VD->getType());
1764 V = EmitBitCastOfLValueToProperType(CGF, V, RealVarTy);
1765 CharUnits Alignment = CGF.getContext().getDeclAlign(VD);
1767 if (VD->getType()->isReferenceType()) {
1768 llvm::LoadInst *LI = CGF.Builder.CreateLoad(V);
1769 LI->setAlignment(Alignment.getQuantity());
1771 LV = CGF.MakeNaturalAlignAddrLValue(V, T);
1773 LV = CGF.MakeAddrLValue(V, T, Alignment);
1775 setObjCGCLValueClass(CGF.getContext(), E, LV);
1779 static LValue EmitFunctionDeclLValue(CodeGenFunction &CGF,
1780 const Expr *E, const FunctionDecl *FD) {
1781 llvm::Value *V = CGF.CGM.GetAddrOfFunction(FD);
1782 if (!FD->hasPrototype()) {
1783 if (const FunctionProtoType *Proto =
1784 FD->getType()->getAs<FunctionProtoType>()) {
1785 // Ugly case: for a K&R-style definition, the type of the definition
1786 // isn't the same as the type of a use. Correct for this with a
1788 QualType NoProtoType =
1789 CGF.getContext().getFunctionNoProtoType(Proto->getReturnType());
1790 NoProtoType = CGF.getContext().getPointerType(NoProtoType);
1791 V = CGF.Builder.CreateBitCast(V, CGF.ConvertType(NoProtoType));
1794 CharUnits Alignment = CGF.getContext().getDeclAlign(FD);
1795 return CGF.MakeAddrLValue(V, E->getType(), Alignment);
1798 static LValue EmitCapturedFieldLValue(CodeGenFunction &CGF, const FieldDecl *FD,
1799 llvm::Value *ThisValue) {
1800 QualType TagType = CGF.getContext().getTagDeclType(FD->getParent());
1801 LValue LV = CGF.MakeNaturalAlignAddrLValue(ThisValue, TagType);
1802 return CGF.EmitLValueForField(LV, FD);
1805 /// Named Registers are named metadata pointing to the register name
1806 /// which will be read from/written to as an argument to the intrinsic
1807 /// @llvm.read/write_register.
1808 /// So far, only the name is being passed down, but other options such as
1809 /// register type, allocation type or even optimization options could be
1810 /// passed down via the metadata node.
1811 static LValue EmitGlobalNamedRegister(const VarDecl *VD,
1813 CharUnits Alignment) {
1814 SmallString<64> Name("llvm.named.register.");
1815 AsmLabelAttr *Asm = VD->getAttr<AsmLabelAttr>();
1816 assert(Asm->getLabel().size() < 64-Name.size() &&
1817 "Register name too big");
1818 Name.append(Asm->getLabel());
1819 llvm::NamedMDNode *M =
1820 CGM.getModule().getOrInsertNamedMetadata(Name);
1821 if (M->getNumOperands() == 0) {
1822 llvm::MDString *Str = llvm::MDString::get(CGM.getLLVMContext(),
1824 llvm::Value *Ops[] = { Str };
1825 M->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
1827 return LValue::MakeGlobalReg(M->getOperand(0), VD->getType(), Alignment);
1830 LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
1831 const NamedDecl *ND = E->getDecl();
1832 CharUnits Alignment = getContext().getDeclAlign(ND);
1833 QualType T = E->getType();
1835 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
1836 // Global Named registers access via intrinsics only
1837 if (VD->getStorageClass() == SC_Register &&
1838 VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl())
1839 return EmitGlobalNamedRegister(VD, CGM, Alignment);
1841 // A DeclRefExpr for a reference initialized by a constant expression can
1842 // appear without being odr-used. Directly emit the constant initializer.
1843 const Expr *Init = VD->getAnyInitializer(VD);
1844 if (Init && !isa<ParmVarDecl>(VD) && VD->getType()->isReferenceType() &&
1845 VD->isUsableInConstantExpressions(getContext()) &&
1846 VD->checkInitIsICE()) {
1847 llvm::Constant *Val =
1848 CGM.EmitConstantValue(*VD->evaluateValue(), VD->getType(), this);
1849 assert(Val && "failed to emit reference constant expression");
1850 // FIXME: Eventually we will want to emit vector element references.
1851 return MakeAddrLValue(Val, T, Alignment);
1855 // FIXME: We should be able to assert this for FunctionDecls as well!
1856 // FIXME: We should be able to assert this for all DeclRefExprs, not just
1857 // those with a valid source location.
1858 assert((ND->isUsed(false) || !isa<VarDecl>(ND) ||
1859 !E->getLocation().isValid()) &&
1860 "Should not use decl without marking it used!");
1862 if (ND->hasAttr<WeakRefAttr>()) {
1863 const auto *VD = cast<ValueDecl>(ND);
1864 llvm::Constant *Aliasee = CGM.GetWeakRefReference(VD);
1865 return MakeAddrLValue(Aliasee, T, Alignment);
1868 if (const auto *VD = dyn_cast<VarDecl>(ND)) {
1869 // Check if this is a global variable.
1870 if (VD->hasLinkage() || VD->isStaticDataMember())
1871 return EmitGlobalVarDeclLValue(*this, E, VD);
1873 bool isBlockVariable = VD->hasAttr<BlocksAttr>();
1875 llvm::Value *V = LocalDeclMap.lookup(VD);
1876 if (!V && VD->isStaticLocal())
1877 V = CGM.getStaticLocalDeclAddress(VD);
1879 // Use special handling for lambdas.
1881 if (FieldDecl *FD = LambdaCaptureFields.lookup(VD)) {
1882 return EmitCapturedFieldLValue(*this, FD, CXXABIThisValue);
1883 } else if (CapturedStmtInfo) {
1884 if (const FieldDecl *FD = CapturedStmtInfo->lookup(VD))
1885 return EmitCapturedFieldLValue(*this, FD,
1886 CapturedStmtInfo->getContextValue());
1889 assert(isa<BlockDecl>(CurCodeDecl) && E->refersToEnclosingLocal());
1890 return MakeAddrLValue(GetAddrOfBlockDecl(VD, isBlockVariable),
1894 assert(V && "DeclRefExpr not entered in LocalDeclMap?");
1896 if (isBlockVariable)
1897 V = BuildBlockByrefAddress(V, VD);
1900 if (VD->getType()->isReferenceType()) {
1901 llvm::LoadInst *LI = Builder.CreateLoad(V);
1902 LI->setAlignment(Alignment.getQuantity());
1904 LV = MakeNaturalAlignAddrLValue(V, T);
1906 LV = MakeAddrLValue(V, T, Alignment);
1909 bool isLocalStorage = VD->hasLocalStorage();
1911 bool NonGCable = isLocalStorage &&
1912 !VD->getType()->isReferenceType() &&
1915 LV.getQuals().removeObjCGCAttr();
1919 bool isImpreciseLifetime =
1920 (isLocalStorage && !VD->hasAttr<ObjCPreciseLifetimeAttr>());
1921 if (isImpreciseLifetime)
1922 LV.setARCPreciseLifetime(ARCImpreciseLifetime);
1923 setObjCGCLValueClass(getContext(), E, LV);
1927 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
1928 return EmitFunctionDeclLValue(*this, E, FD);
1930 llvm_unreachable("Unhandled DeclRefExpr");
1933 LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
1934 // __extension__ doesn't affect lvalue-ness.
1935 if (E->getOpcode() == UO_Extension)
1936 return EmitLValue(E->getSubExpr());
1938 QualType ExprTy = getContext().getCanonicalType(E->getSubExpr()->getType());
1939 switch (E->getOpcode()) {
1940 default: llvm_unreachable("Unknown unary operator lvalue!");
1942 QualType T = E->getSubExpr()->getType()->getPointeeType();
1943 assert(!T.isNull() && "CodeGenFunction::EmitUnaryOpLValue: Illegal type");
1945 LValue LV = MakeNaturalAlignAddrLValue(EmitScalarExpr(E->getSubExpr()), T);
1946 LV.getQuals().setAddressSpace(ExprTy.getAddressSpace());
1948 // We should not generate __weak write barrier on indirect reference
1949 // of a pointer to object; as in void foo (__weak id *param); *param = 0;
1950 // But, we continue to generate __strong write barrier on indirect write
1951 // into a pointer to object.
1952 if (getLangOpts().ObjC1 &&
1953 getLangOpts().getGC() != LangOptions::NonGC &&
1955 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
1960 LValue LV = EmitLValue(E->getSubExpr());
1961 assert(LV.isSimple() && "real/imag on non-ordinary l-value");
1962 llvm::Value *Addr = LV.getAddress();
1964 // __real is valid on scalars. This is a faster way of testing that.
1965 // __imag can only produce an rvalue on scalars.
1966 if (E->getOpcode() == UO_Real &&
1967 !cast<llvm::PointerType>(Addr->getType())
1968 ->getElementType()->isStructTy()) {
1969 assert(E->getSubExpr()->getType()->isArithmeticType());
1973 assert(E->getSubExpr()->getType()->isAnyComplexType());
1975 unsigned Idx = E->getOpcode() == UO_Imag;
1976 return MakeAddrLValue(Builder.CreateStructGEP(LV.getAddress(),
1982 LValue LV = EmitLValue(E->getSubExpr());
1983 bool isInc = E->getOpcode() == UO_PreInc;
1985 if (E->getType()->isAnyComplexType())
1986 EmitComplexPrePostIncDec(E, LV, isInc, true/*isPre*/);
1988 EmitScalarPrePostIncDec(E, LV, isInc, true/*isPre*/);
1994 LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
1995 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromLiteral(E),
1999 LValue CodeGenFunction::EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E) {
2000 return MakeAddrLValue(CGM.GetAddrOfConstantStringFromObjCEncode(E),
2004 static void ConvertUTF8ToWideString(unsigned CharByteWidth, StringRef Source,
2005 SmallString<32>& Target) {
2006 Target.resize(CharByteWidth * (Source.size() + 1));
2007 char *ResultPtr = &Target[0];
2008 const UTF8 *ErrorPtr;
2009 bool success = ConvertUTF8toWide(CharByteWidth, Source, ResultPtr, ErrorPtr);
2012 Target.resize(ResultPtr - &Target[0]);
2015 LValue CodeGenFunction::EmitPredefinedLValue(const PredefinedExpr *E) {
2016 switch (E->getIdentType()) {
2018 return EmitUnsupportedLValue(E, "predefined expression");
2020 case PredefinedExpr::Func:
2021 case PredefinedExpr::Function:
2022 case PredefinedExpr::LFunction:
2023 case PredefinedExpr::FuncDName:
2024 case PredefinedExpr::FuncSig:
2025 case PredefinedExpr::PrettyFunction: {
2026 PredefinedExpr::IdentType IdentType = E->getIdentType();
2029 // FIXME: We should use the string literal mangling for the Microsoft C++
2030 // ABI so that strings get merged.
2031 switch (IdentType) {
2032 default: llvm_unreachable("Invalid type");
2033 case PredefinedExpr::Func: GVName = "__func__."; break;
2034 case PredefinedExpr::Function: GVName = "__FUNCTION__."; break;
2035 case PredefinedExpr::FuncDName: GVName = "__FUNCDNAME__."; break;
2036 case PredefinedExpr::FuncSig: GVName = "__FUNCSIG__."; break;
2037 case PredefinedExpr::LFunction: GVName = "L__FUNCTION__."; break;
2038 case PredefinedExpr::PrettyFunction: GVName = "__PRETTY_FUNCTION__."; break;
2041 StringRef FnName = CurFn->getName();
2042 if (FnName.startswith("\01"))
2043 FnName = FnName.substr(1);
2046 // If this is outside of a function use the top level decl.
2047 const Decl *CurDecl = CurCodeDecl;
2048 if (!CurDecl || isa<VarDecl>(CurDecl))
2049 CurDecl = getContext().getTranslationUnitDecl();
2051 const Type *ElemType = E->getType()->getArrayElementTypeNoTypeQual();
2052 std::string FunctionName;
2053 if (isa<BlockDecl>(CurDecl)) {
2054 // Blocks use the mangled function name.
2055 // FIXME: ComputeName should handle blocks.
2056 FunctionName = FnName.str();
2057 } else if (isa<CapturedDecl>(CurDecl)) {
2058 // For a captured statement, the function name is its enclosing
2059 // function name not the one compiler generated.
2060 FunctionName = PredefinedExpr::ComputeName(IdentType, CurDecl);
2062 FunctionName = PredefinedExpr::ComputeName(IdentType, CurDecl);
2063 assert(cast<ConstantArrayType>(E->getType())->getSize() - 1 ==
2064 FunctionName.size() &&
2065 "Computed __func__ length differs from type!");
2069 if (ElemType->isWideCharType()) {
2070 SmallString<32> RawChars;
2071 ConvertUTF8ToWideString(
2072 getContext().getTypeSizeInChars(ElemType).getQuantity(), FunctionName,
2074 StringLiteral *SL = StringLiteral::Create(
2075 getContext(), RawChars, StringLiteral::Wide,
2076 /*Pascal = */ false, E->getType(), E->getLocation());
2077 C = CGM.GetAddrOfConstantStringFromLiteral(SL);
2079 C = CGM.GetAddrOfConstantCString(FunctionName, GVName.c_str(), 1);
2081 return MakeAddrLValue(C, E->getType());
2086 /// Emit a type description suitable for use by a runtime sanitizer library. The
2087 /// format of a type descriptor is
2090 /// { i16 TypeKind, i16 TypeInfo }
2093 /// followed by an array of i8 containing the type name. TypeKind is 0 for an
2094 /// integer, 1 for a floating point value, and -1 for anything else.
2095 llvm::Constant *CodeGenFunction::EmitCheckTypeDescriptor(QualType T) {
2096 // Only emit each type's descriptor once.
2097 if (llvm::Constant *C = CGM.getTypeDescriptorFromMap(T))
2100 uint16_t TypeKind = -1;
2101 uint16_t TypeInfo = 0;
2103 if (T->isIntegerType()) {
2105 TypeInfo = (llvm::Log2_32(getContext().getTypeSize(T)) << 1) |
2106 (T->isSignedIntegerType() ? 1 : 0);
2107 } else if (T->isFloatingType()) {
2109 TypeInfo = getContext().getTypeSize(T);
2112 // Format the type name as if for a diagnostic, including quotes and
2113 // optionally an 'aka'.
2114 SmallString<32> Buffer;
2115 CGM.getDiags().ConvertArgToString(DiagnosticsEngine::ak_qualtype,
2116 (intptr_t)T.getAsOpaquePtr(),
2117 StringRef(), StringRef(), None, Buffer,
2118 ArrayRef<intptr_t>());
2120 llvm::Constant *Components[] = {
2121 Builder.getInt16(TypeKind), Builder.getInt16(TypeInfo),
2122 llvm::ConstantDataArray::getString(getLLVMContext(), Buffer)
2124 llvm::Constant *Descriptor = llvm::ConstantStruct::getAnon(Components);
2126 auto *GV = new llvm::GlobalVariable(
2127 CGM.getModule(), Descriptor->getType(),
2128 /*isConstant=*/true, llvm::GlobalVariable::PrivateLinkage, Descriptor);
2129 GV->setUnnamedAddr(true);
2130 CGM.disableSanitizerForGlobal(GV);
2132 // Remember the descriptor for this type.
2133 CGM.setTypeDescriptorInMap(T, GV);
2138 llvm::Value *CodeGenFunction::EmitCheckValue(llvm::Value *V) {
2139 llvm::Type *TargetTy = IntPtrTy;
2141 // Floating-point types which fit into intptr_t are bitcast to integers
2142 // and then passed directly (after zero-extension, if necessary).
2143 if (V->getType()->isFloatingPointTy()) {
2144 unsigned Bits = V->getType()->getPrimitiveSizeInBits();
2145 if (Bits <= TargetTy->getIntegerBitWidth())
2146 V = Builder.CreateBitCast(V, llvm::Type::getIntNTy(getLLVMContext(),
2150 // Integers which fit in intptr_t are zero-extended and passed directly.
2151 if (V->getType()->isIntegerTy() &&
2152 V->getType()->getIntegerBitWidth() <= TargetTy->getIntegerBitWidth())
2153 return Builder.CreateZExt(V, TargetTy);
2155 // Pointers are passed directly, everything else is passed by address.
2156 if (!V->getType()->isPointerTy()) {
2157 llvm::Value *Ptr = CreateTempAlloca(V->getType());
2158 Builder.CreateStore(V, Ptr);
2161 return Builder.CreatePtrToInt(V, TargetTy);
2164 /// \brief Emit a representation of a SourceLocation for passing to a handler
2165 /// in a sanitizer runtime library. The format for this data is:
2167 /// struct SourceLocation {
2168 /// const char *Filename;
2169 /// int32_t Line, Column;
2172 /// For an invalid SourceLocation, the Filename pointer is null.
2173 llvm::Constant *CodeGenFunction::EmitCheckSourceLocation(SourceLocation Loc) {
2174 llvm::Constant *Filename;
2177 PresumedLoc PLoc = getContext().getSourceManager().getPresumedLoc(Loc);
2178 if (PLoc.isValid()) {
2179 auto FilenameGV = CGM.GetAddrOfConstantCString(PLoc.getFilename(), ".src");
2180 CGM.disableSanitizerForGlobal(FilenameGV);
2181 Filename = FilenameGV;
2182 Line = PLoc.getLine();
2183 Column = PLoc.getColumn();
2185 Filename = llvm::Constant::getNullValue(Int8PtrTy);
2189 llvm::Constant *Data[] = {Filename, Builder.getInt32(Line),
2190 Builder.getInt32(Column)};
2192 return llvm::ConstantStruct::getAnon(Data);
2195 void CodeGenFunction::EmitCheck(llvm::Value *Checked, StringRef CheckName,
2196 ArrayRef<llvm::Constant *> StaticArgs,
2197 ArrayRef<llvm::Value *> DynamicArgs,
2198 CheckRecoverableKind RecoverKind) {
2199 assert(SanOpts != &SanitizerOptions::Disabled);
2200 assert(IsSanitizerScope);
2202 if (CGM.getCodeGenOpts().SanitizeUndefinedTrapOnError) {
2203 assert (RecoverKind != CRK_AlwaysRecoverable &&
2204 "Runtime call required for AlwaysRecoverable kind!");
2205 return EmitTrapCheck(Checked);
2208 llvm::BasicBlock *Cont = createBasicBlock("cont");
2210 llvm::BasicBlock *Handler = createBasicBlock("handler." + CheckName);
2212 llvm::Instruction *Branch = Builder.CreateCondBr(Checked, Cont, Handler);
2214 // Give hint that we very much don't expect to execute the handler
2215 // Value chosen to match UR_NONTAKEN_WEIGHT, see BranchProbabilityInfo.cpp
2216 llvm::MDBuilder MDHelper(getLLVMContext());
2217 llvm::MDNode *Node = MDHelper.createBranchWeights((1U << 20) - 1, 1);
2218 Branch->setMetadata(llvm::LLVMContext::MD_prof, Node);
2222 llvm::Constant *Info = llvm::ConstantStruct::getAnon(StaticArgs);
2224 new llvm::GlobalVariable(CGM.getModule(), Info->getType(), false,
2225 llvm::GlobalVariable::PrivateLinkage, Info);
2226 InfoPtr->setUnnamedAddr(true);
2227 CGM.disableSanitizerForGlobal(InfoPtr);
2229 SmallVector<llvm::Value *, 4> Args;
2230 SmallVector<llvm::Type *, 4> ArgTypes;
2231 Args.reserve(DynamicArgs.size() + 1);
2232 ArgTypes.reserve(DynamicArgs.size() + 1);
2234 // Handler functions take an i8* pointing to the (handler-specific) static
2235 // information block, followed by a sequence of intptr_t arguments
2236 // representing operand values.
2237 Args.push_back(Builder.CreateBitCast(InfoPtr, Int8PtrTy));
2238 ArgTypes.push_back(Int8PtrTy);
2239 for (size_t i = 0, n = DynamicArgs.size(); i != n; ++i) {
2240 Args.push_back(EmitCheckValue(DynamicArgs[i]));
2241 ArgTypes.push_back(IntPtrTy);
2244 bool Recover = RecoverKind == CRK_AlwaysRecoverable ||
2245 (RecoverKind == CRK_Recoverable &&
2246 CGM.getCodeGenOpts().SanitizeRecover);
2248 llvm::FunctionType *FnType =
2249 llvm::FunctionType::get(CGM.VoidTy, ArgTypes, false);
2250 llvm::AttrBuilder B;
2252 B.addAttribute(llvm::Attribute::NoReturn)
2253 .addAttribute(llvm::Attribute::NoUnwind);
2255 B.addAttribute(llvm::Attribute::UWTable);
2257 // Checks that have two variants use a suffix to differentiate them
2258 bool NeedsAbortSuffix = RecoverKind != CRK_Unrecoverable &&
2259 !CGM.getCodeGenOpts().SanitizeRecover;
2260 std::string FunctionName = ("__ubsan_handle_" + CheckName +
2261 (NeedsAbortSuffix? "_abort" : "")).str();
2262 llvm::Value *Fn = CGM.CreateRuntimeFunction(
2263 FnType, FunctionName,
2264 llvm::AttributeSet::get(getLLVMContext(),
2265 llvm::AttributeSet::FunctionIndex, B));
2266 llvm::CallInst *HandlerCall = EmitNounwindRuntimeCall(Fn, Args);
2268 Builder.CreateBr(Cont);
2270 HandlerCall->setDoesNotReturn();
2271 Builder.CreateUnreachable();
2277 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked) {
2278 llvm::BasicBlock *Cont = createBasicBlock("cont");
2280 // If we're optimizing, collapse all calls to trap down to just one per
2281 // function to save on code size.
2282 if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB) {
2283 TrapBB = createBasicBlock("trap");
2284 Builder.CreateCondBr(Checked, Cont, TrapBB);
2286 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::trap);
2287 llvm::CallInst *TrapCall = Builder.CreateCall(F);
2288 TrapCall->setDoesNotReturn();
2289 TrapCall->setDoesNotThrow();
2290 Builder.CreateUnreachable();
2292 Builder.CreateCondBr(Checked, Cont, TrapBB);
2298 /// isSimpleArrayDecayOperand - If the specified expr is a simple decay from an
2299 /// array to pointer, return the array subexpression.
2300 static const Expr *isSimpleArrayDecayOperand(const Expr *E) {
2301 // If this isn't just an array->pointer decay, bail out.
2302 const auto *CE = dyn_cast<CastExpr>(E);
2303 if (!CE || CE->getCastKind() != CK_ArrayToPointerDecay)
2306 // If this is a decay from variable width array, bail out.
2307 const Expr *SubExpr = CE->getSubExpr();
2308 if (SubExpr->getType()->isVariableArrayType())
2314 LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
2316 // The index must always be an integer, which is not an aggregate. Emit it.
2317 llvm::Value *Idx = EmitScalarExpr(E->getIdx());
2318 QualType IdxTy = E->getIdx()->getType();
2319 bool IdxSigned = IdxTy->isSignedIntegerOrEnumerationType();
2321 if (SanOpts->ArrayBounds)
2322 EmitBoundsCheck(E, E->getBase(), Idx, IdxTy, Accessed);
2324 // If the base is a vector type, then we are forming a vector element lvalue
2325 // with this subscript.
2326 if (E->getBase()->getType()->isVectorType()) {
2327 // Emit the vector as an lvalue to get its address.
2328 LValue LHS = EmitLValue(E->getBase());
2329 assert(LHS.isSimple() && "Can only subscript lvalue vectors here!");
2330 return LValue::MakeVectorElt(LHS.getAddress(), Idx,
2331 E->getBase()->getType(), LHS.getAlignment());
2334 // Extend or truncate the index type to 32 or 64-bits.
2335 if (Idx->getType() != IntPtrTy)
2336 Idx = Builder.CreateIntCast(Idx, IntPtrTy, IdxSigned, "idxprom");
2338 // We know that the pointer points to a type of the correct size, unless the
2339 // size is a VLA or Objective-C interface.
2340 llvm::Value *Address = nullptr;
2341 CharUnits ArrayAlignment;
2342 if (const VariableArrayType *vla =
2343 getContext().getAsVariableArrayType(E->getType())) {
2344 // The base must be a pointer, which is not an aggregate. Emit
2345 // it. It needs to be emitted first in case it's what captures
2347 Address = EmitScalarExpr(E->getBase());
2349 // The element count here is the total number of non-VLA elements.
2350 llvm::Value *numElements = getVLASize(vla).first;
2352 // Effectively, the multiply by the VLA size is part of the GEP.
2353 // GEP indexes are signed, and scaling an index isn't permitted to
2354 // signed-overflow, so we use the same semantics for our explicit
2355 // multiply. We suppress this if overflow is not undefined behavior.
2356 if (getLangOpts().isSignedOverflowDefined()) {
2357 Idx = Builder.CreateMul(Idx, numElements);
2358 Address = Builder.CreateGEP(Address, Idx, "arrayidx");
2360 Idx = Builder.CreateNSWMul(Idx, numElements);
2361 Address = Builder.CreateInBoundsGEP(Address, Idx, "arrayidx");
2363 } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
2364 // Indexing over an interface, as in "NSString *P; P[4];"
2365 llvm::Value *InterfaceSize =
2366 llvm::ConstantInt::get(Idx->getType(),
2367 getContext().getTypeSizeInChars(OIT).getQuantity());
2369 Idx = Builder.CreateMul(Idx, InterfaceSize);
2371 // The base must be a pointer, which is not an aggregate. Emit it.
2372 llvm::Value *Base = EmitScalarExpr(E->getBase());
2373 Address = EmitCastToVoidPtr(Base);
2374 Address = Builder.CreateGEP(Address, Idx, "arrayidx");
2375 Address = Builder.CreateBitCast(Address, Base->getType());
2376 } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
2377 // If this is A[i] where A is an array, the frontend will have decayed the
2378 // base to be a ArrayToPointerDecay implicit cast. While correct, it is
2379 // inefficient at -O0 to emit a "gep A, 0, 0" when codegen'ing it, then a
2380 // "gep x, i" here. Emit one "gep A, 0, i".
2381 assert(Array->getType()->isArrayType() &&
2382 "Array to pointer decay must have array source type!");
2384 // For simple multidimensional array indexing, set the 'accessed' flag for
2385 // better bounds-checking of the base expression.
2386 if (const auto *ASE = dyn_cast<ArraySubscriptExpr>(Array))
2387 ArrayLV = EmitArraySubscriptExpr(ASE, /*Accessed*/ true);
2389 ArrayLV = EmitLValue(Array);
2390 llvm::Value *ArrayPtr = ArrayLV.getAddress();
2391 llvm::Value *Zero = llvm::ConstantInt::get(Int32Ty, 0);
2392 llvm::Value *Args[] = { Zero, Idx };
2394 // Propagate the alignment from the array itself to the result.
2395 ArrayAlignment = ArrayLV.getAlignment();
2397 if (getLangOpts().isSignedOverflowDefined())
2398 Address = Builder.CreateGEP(ArrayPtr, Args, "arrayidx");
2400 Address = Builder.CreateInBoundsGEP(ArrayPtr, Args, "arrayidx");
2402 // The base must be a pointer, which is not an aggregate. Emit it.
2403 llvm::Value *Base = EmitScalarExpr(E->getBase());
2404 if (getLangOpts().isSignedOverflowDefined())
2405 Address = Builder.CreateGEP(Base, Idx, "arrayidx");
2407 Address = Builder.CreateInBoundsGEP(Base, Idx, "arrayidx");
2410 QualType T = E->getBase()->getType()->getPointeeType();
2411 assert(!T.isNull() &&
2412 "CodeGenFunction::EmitArraySubscriptExpr(): Illegal base type");
2415 // Limit the alignment to that of the result type.
2417 if (!ArrayAlignment.isZero()) {
2418 CharUnits Align = getContext().getTypeAlignInChars(T);
2419 ArrayAlignment = std::min(Align, ArrayAlignment);
2420 LV = MakeAddrLValue(Address, T, ArrayAlignment);
2422 LV = MakeNaturalAlignAddrLValue(Address, T);
2425 LV.getQuals().setAddressSpace(E->getBase()->getType().getAddressSpace());
2427 if (getLangOpts().ObjC1 &&
2428 getLangOpts().getGC() != LangOptions::NonGC) {
2429 LV.setNonGC(!E->isOBJCGCCandidate(getContext()));
2430 setObjCGCLValueClass(getContext(), E, LV);
2436 llvm::Constant *GenerateConstantVector(CGBuilderTy &Builder,
2437 SmallVectorImpl<unsigned> &Elts) {
2438 SmallVector<llvm::Constant*, 4> CElts;
2439 for (unsigned i = 0, e = Elts.size(); i != e; ++i)
2440 CElts.push_back(Builder.getInt32(Elts[i]));
2442 return llvm::ConstantVector::get(CElts);
2445 LValue CodeGenFunction::
2446 EmitExtVectorElementExpr(const ExtVectorElementExpr *E) {
2447 // Emit the base vector as an l-value.
2450 // ExtVectorElementExpr's base can either be a vector or pointer to vector.
2452 // If it is a pointer to a vector, emit the address and form an lvalue with
2454 llvm::Value *Ptr = EmitScalarExpr(E->getBase());
2455 const PointerType *PT = E->getBase()->getType()->getAs<PointerType>();
2456 Base = MakeAddrLValue(Ptr, PT->getPointeeType());
2457 Base.getQuals().removeObjCGCAttr();
2458 } else if (E->getBase()->isGLValue()) {
2459 // Otherwise, if the base is an lvalue ( as in the case of foo.x.x),
2460 // emit the base as an lvalue.
2461 assert(E->getBase()->getType()->isVectorType());
2462 Base = EmitLValue(E->getBase());
2464 // Otherwise, the base is a normal rvalue (as in (V+V).x), emit it as such.
2465 assert(E->getBase()->getType()->isVectorType() &&
2466 "Result must be a vector");
2467 llvm::Value *Vec = EmitScalarExpr(E->getBase());
2469 // Store the vector to memory (because LValue wants an address).
2470 llvm::Value *VecMem = CreateMemTemp(E->getBase()->getType());
2471 Builder.CreateStore(Vec, VecMem);
2472 Base = MakeAddrLValue(VecMem, E->getBase()->getType());
2476 E->getType().withCVRQualifiers(Base.getQuals().getCVRQualifiers());
2478 // Encode the element access list into a vector of unsigned indices.
2479 SmallVector<unsigned, 4> Indices;
2480 E->getEncodedElementAccess(Indices);
2482 if (Base.isSimple()) {
2483 llvm::Constant *CV = GenerateConstantVector(Builder, Indices);
2484 return LValue::MakeExtVectorElt(Base.getAddress(), CV, type,
2485 Base.getAlignment());
2487 assert(Base.isExtVectorElt() && "Can only subscript lvalue vec elts here!");
2489 llvm::Constant *BaseElts = Base.getExtVectorElts();
2490 SmallVector<llvm::Constant *, 4> CElts;
2492 for (unsigned i = 0, e = Indices.size(); i != e; ++i)
2493 CElts.push_back(BaseElts->getAggregateElement(Indices[i]));
2494 llvm::Constant *CV = llvm::ConstantVector::get(CElts);
2495 return LValue::MakeExtVectorElt(Base.getExtVectorAddr(), CV, type,
2496 Base.getAlignment());
2499 LValue CodeGenFunction::EmitMemberExpr(const MemberExpr *E) {
2500 Expr *BaseExpr = E->getBase();
2502 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
2505 llvm::Value *Ptr = EmitScalarExpr(BaseExpr);
2506 QualType PtrTy = BaseExpr->getType()->getPointeeType();
2507 EmitTypeCheck(TCK_MemberAccess, E->getExprLoc(), Ptr, PtrTy);
2508 BaseLV = MakeNaturalAlignAddrLValue(Ptr, PtrTy);
2510 BaseLV = EmitCheckedLValue(BaseExpr, TCK_MemberAccess);
2512 NamedDecl *ND = E->getMemberDecl();
2513 if (auto *Field = dyn_cast<FieldDecl>(ND)) {
2514 LValue LV = EmitLValueForField(BaseLV, Field);
2515 setObjCGCLValueClass(getContext(), E, LV);
2519 if (auto *VD = dyn_cast<VarDecl>(ND))
2520 return EmitGlobalVarDeclLValue(*this, E, VD);
2522 if (const auto *FD = dyn_cast<FunctionDecl>(ND))
2523 return EmitFunctionDeclLValue(*this, E, FD);
2525 llvm_unreachable("Unhandled member declaration!");
2528 /// Given that we are currently emitting a lambda, emit an l-value for
2529 /// one of its members.
2530 LValue CodeGenFunction::EmitLValueForLambdaField(const FieldDecl *Field) {
2531 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent()->isLambda());
2532 assert(cast<CXXMethodDecl>(CurCodeDecl)->getParent() == Field->getParent());
2533 QualType LambdaTagType =
2534 getContext().getTagDeclType(Field->getParent());
2535 LValue LambdaLV = MakeNaturalAlignAddrLValue(CXXABIThisValue, LambdaTagType);
2536 return EmitLValueForField(LambdaLV, Field);
2539 LValue CodeGenFunction::EmitLValueForField(LValue base,
2540 const FieldDecl *field) {
2541 if (field->isBitField()) {
2542 const CGRecordLayout &RL =
2543 CGM.getTypes().getCGRecordLayout(field->getParent());
2544 const CGBitFieldInfo &Info = RL.getBitFieldInfo(field);
2545 llvm::Value *Addr = base.getAddress();
2546 unsigned Idx = RL.getLLVMFieldNo(field);
2548 // For structs, we GEP to the field that the record layout suggests.
2549 Addr = Builder.CreateStructGEP(Addr, Idx, field->getName());
2550 // Get the access type.
2551 llvm::Type *PtrTy = llvm::Type::getIntNPtrTy(
2552 getLLVMContext(), Info.StorageSize,
2553 CGM.getContext().getTargetAddressSpace(base.getType()));
2554 if (Addr->getType() != PtrTy)
2555 Addr = Builder.CreateBitCast(Addr, PtrTy);
2557 QualType fieldType =
2558 field->getType().withCVRQualifiers(base.getVRQualifiers());
2559 return LValue::MakeBitfield(Addr, Info, fieldType, base.getAlignment());
2562 const RecordDecl *rec = field->getParent();
2563 QualType type = field->getType();
2564 CharUnits alignment = getContext().getDeclAlign(field);
2566 // FIXME: It should be impossible to have an LValue without alignment for a
2568 if (!base.getAlignment().isZero())
2569 alignment = std::min(alignment, base.getAlignment());
2571 bool mayAlias = rec->hasAttr<MayAliasAttr>();
2573 llvm::Value *addr = base.getAddress();
2574 unsigned cvr = base.getVRQualifiers();
2575 bool TBAAPath = CGM.getCodeGenOpts().StructPathTBAA;
2576 if (rec->isUnion()) {
2577 // For unions, there is no pointer adjustment.
2578 assert(!type->isReferenceType() && "union has reference member");
2579 // TODO: handle path-aware TBAA for union.
2582 // For structs, we GEP to the field that the record layout suggests.
2583 unsigned idx = CGM.getTypes().getCGRecordLayout(rec).getLLVMFieldNo(field);
2584 addr = Builder.CreateStructGEP(addr, idx, field->getName());
2586 // If this is a reference field, load the reference right now.
2587 if (const ReferenceType *refType = type->getAs<ReferenceType>()) {
2588 llvm::LoadInst *load = Builder.CreateLoad(addr, "ref");
2589 if (cvr & Qualifiers::Volatile) load->setVolatile(true);
2590 load->setAlignment(alignment.getQuantity());
2592 // Loading the reference will disable path-aware TBAA.
2594 if (CGM.shouldUseTBAA()) {
2597 tbaa = CGM.getTBAAInfo(getContext().CharTy);
2599 tbaa = CGM.getTBAAInfo(type);
2601 CGM.DecorateInstruction(load, tbaa);
2606 type = refType->getPointeeType();
2607 if (type->isIncompleteType())
2608 alignment = CharUnits();
2610 alignment = getContext().getTypeAlignInChars(type);
2611 cvr = 0; // qualifiers don't recursively apply to referencee
2615 // Make sure that the address is pointing to the right type. This is critical
2616 // for both unions and structs. A union needs a bitcast, a struct element
2617 // will need a bitcast if the LLVM type laid out doesn't match the desired
2619 addr = EmitBitCastOfLValueToProperType(*this, addr,
2620 CGM.getTypes().ConvertTypeForMem(type),
2623 if (field->hasAttr<AnnotateAttr>())
2624 addr = EmitFieldAnnotations(field, addr);
2626 LValue LV = MakeAddrLValue(addr, type, alignment);
2627 LV.getQuals().addCVRQualifiers(cvr);
2629 const ASTRecordLayout &Layout =
2630 getContext().getASTRecordLayout(field->getParent());
2631 // Set the base type to be the base type of the base LValue and
2632 // update offset to be relative to the base type.
2633 LV.setTBAABaseType(mayAlias ? getContext().CharTy : base.getTBAABaseType());
2634 LV.setTBAAOffset(mayAlias ? 0 : base.getTBAAOffset() +
2635 Layout.getFieldOffset(field->getFieldIndex()) /
2636 getContext().getCharWidth());
2639 // __weak attribute on a field is ignored.
2640 if (LV.getQuals().getObjCGCAttr() == Qualifiers::Weak)
2641 LV.getQuals().removeObjCGCAttr();
2643 // Fields of may_alias structs act like 'char' for TBAA purposes.
2644 // FIXME: this should get propagated down through anonymous structs
2646 if (mayAlias && LV.getTBAAInfo())
2647 LV.setTBAAInfo(CGM.getTBAAInfo(getContext().CharTy));
2653 CodeGenFunction::EmitLValueForFieldInitialization(LValue Base,
2654 const FieldDecl *Field) {
2655 QualType FieldType = Field->getType();
2657 if (!FieldType->isReferenceType())
2658 return EmitLValueForField(Base, Field);
2660 const CGRecordLayout &RL =
2661 CGM.getTypes().getCGRecordLayout(Field->getParent());
2662 unsigned idx = RL.getLLVMFieldNo(Field);
2663 llvm::Value *V = Builder.CreateStructGEP(Base.getAddress(), idx);
2664 assert(!FieldType.getObjCGCAttr() && "fields cannot have GC attrs");
2666 // Make sure that the address is pointing to the right type. This is critical
2667 // for both unions and structs. A union needs a bitcast, a struct element
2668 // will need a bitcast if the LLVM type laid out doesn't match the desired
2670 llvm::Type *llvmType = ConvertTypeForMem(FieldType);
2671 V = EmitBitCastOfLValueToProperType(*this, V, llvmType, Field->getName());
2673 CharUnits Alignment = getContext().getDeclAlign(Field);
2675 // FIXME: It should be impossible to have an LValue without alignment for a
2677 if (!Base.getAlignment().isZero())
2678 Alignment = std::min(Alignment, Base.getAlignment());
2680 return MakeAddrLValue(V, FieldType, Alignment);
2683 LValue CodeGenFunction::EmitCompoundLiteralLValue(const CompoundLiteralExpr *E){
2684 if (E->isFileScope()) {
2685 llvm::Value *GlobalPtr = CGM.GetAddrOfConstantCompoundLiteral(E);
2686 return MakeAddrLValue(GlobalPtr, E->getType());
2688 if (E->getType()->isVariablyModifiedType())
2689 // make sure to emit the VLA size.
2690 EmitVariablyModifiedType(E->getType());
2692 llvm::Value *DeclPtr = CreateMemTemp(E->getType(), ".compoundliteral");
2693 const Expr *InitExpr = E->getInitializer();
2694 LValue Result = MakeAddrLValue(DeclPtr, E->getType());
2696 EmitAnyExprToMem(InitExpr, DeclPtr, E->getType().getQualifiers(),
2702 LValue CodeGenFunction::EmitInitListLValue(const InitListExpr *E) {
2703 if (!E->isGLValue())
2704 // Initializing an aggregate temporary in C++11: T{...}.
2705 return EmitAggExprToLValue(E);
2707 // An lvalue initializer list must be initializing a reference.
2708 assert(E->getNumInits() == 1 && "reference init with multiple values");
2709 return EmitLValue(E->getInit(0));
2712 /// Emit the operand of a glvalue conditional operator. This is either a glvalue
2713 /// or a (possibly-parenthesized) throw-expression. If this is a throw, no
2714 /// LValue is returned and the current block has been terminated.
2715 static Optional<LValue> EmitLValueOrThrowExpression(CodeGenFunction &CGF,
2716 const Expr *Operand) {
2717 if (auto *ThrowExpr = dyn_cast<CXXThrowExpr>(Operand->IgnoreParens())) {
2718 CGF.EmitCXXThrowExpr(ThrowExpr, /*KeepInsertionPoint*/false);
2722 return CGF.EmitLValue(Operand);
2725 LValue CodeGenFunction::
2726 EmitConditionalOperatorLValue(const AbstractConditionalOperator *expr) {
2727 if (!expr->isGLValue()) {
2728 // ?: here should be an aggregate.
2729 assert(hasAggregateEvaluationKind(expr->getType()) &&
2730 "Unexpected conditional operator!");
2731 return EmitAggExprToLValue(expr);
2734 OpaqueValueMapping binding(*this, expr);
2735 RegionCounter Cnt = getPGORegionCounter(expr);
2737 const Expr *condExpr = expr->getCond();
2739 if (ConstantFoldsToSimpleInteger(condExpr, CondExprBool)) {
2740 const Expr *live = expr->getTrueExpr(), *dead = expr->getFalseExpr();
2741 if (!CondExprBool) std::swap(live, dead);
2743 if (!ContainsLabel(dead)) {
2744 // If the true case is live, we need to track its region.
2746 Cnt.beginRegion(Builder);
2747 return EmitLValue(live);
2751 llvm::BasicBlock *lhsBlock = createBasicBlock("cond.true");
2752 llvm::BasicBlock *rhsBlock = createBasicBlock("cond.false");
2753 llvm::BasicBlock *contBlock = createBasicBlock("cond.end");
2755 ConditionalEvaluation eval(*this);
2756 EmitBranchOnBoolExpr(condExpr, lhsBlock, rhsBlock, Cnt.getCount());
2758 // Any temporaries created here are conditional.
2759 EmitBlock(lhsBlock);
2760 Cnt.beginRegion(Builder);
2762 Optional<LValue> lhs =
2763 EmitLValueOrThrowExpression(*this, expr->getTrueExpr());
2766 if (lhs && !lhs->isSimple())
2767 return EmitUnsupportedLValue(expr, "conditional operator");
2769 lhsBlock = Builder.GetInsertBlock();
2771 Builder.CreateBr(contBlock);
2773 // Any temporaries created here are conditional.
2774 EmitBlock(rhsBlock);
2776 Optional<LValue> rhs =
2777 EmitLValueOrThrowExpression(*this, expr->getFalseExpr());
2779 if (rhs && !rhs->isSimple())
2780 return EmitUnsupportedLValue(expr, "conditional operator");
2781 rhsBlock = Builder.GetInsertBlock();
2783 EmitBlock(contBlock);
2786 llvm::PHINode *phi = Builder.CreatePHI(lhs->getAddress()->getType(),
2788 phi->addIncoming(lhs->getAddress(), lhsBlock);
2789 phi->addIncoming(rhs->getAddress(), rhsBlock);
2790 return MakeAddrLValue(phi, expr->getType());
2792 assert((lhs || rhs) &&
2793 "both operands of glvalue conditional are throw-expressions?");
2794 return lhs ? *lhs : *rhs;
2798 /// EmitCastLValue - Casts are never lvalues unless that cast is to a reference
2799 /// type. If the cast is to a reference, we can have the usual lvalue result,
2800 /// otherwise if a cast is needed by the code generator in an lvalue context,
2801 /// then it must mean that we need the address of an aggregate in order to
2802 /// access one of its members. This can happen for all the reasons that casts
2803 /// are permitted with aggregate result, including noop aggregate casts, and
2804 /// cast from scalar to union.
2805 LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
2806 switch (E->getCastKind()) {
2809 case CK_ArrayToPointerDecay:
2810 case CK_FunctionToPointerDecay:
2811 case CK_NullToMemberPointer:
2812 case CK_NullToPointer:
2813 case CK_IntegralToPointer:
2814 case CK_PointerToIntegral:
2815 case CK_PointerToBoolean:
2816 case CK_VectorSplat:
2817 case CK_IntegralCast:
2818 case CK_IntegralToBoolean:
2819 case CK_IntegralToFloating:
2820 case CK_FloatingToIntegral:
2821 case CK_FloatingToBoolean:
2822 case CK_FloatingCast:
2823 case CK_FloatingRealToComplex:
2824 case CK_FloatingComplexToReal:
2825 case CK_FloatingComplexToBoolean:
2826 case CK_FloatingComplexCast:
2827 case CK_FloatingComplexToIntegralComplex:
2828 case CK_IntegralRealToComplex:
2829 case CK_IntegralComplexToReal:
2830 case CK_IntegralComplexToBoolean:
2831 case CK_IntegralComplexCast:
2832 case CK_IntegralComplexToFloatingComplex:
2833 case CK_DerivedToBaseMemberPointer:
2834 case CK_BaseToDerivedMemberPointer:
2835 case CK_MemberPointerToBoolean:
2836 case CK_ReinterpretMemberPointer:
2837 case CK_AnyPointerToBlockPointerCast:
2838 case CK_ARCProduceObject:
2839 case CK_ARCConsumeObject:
2840 case CK_ARCReclaimReturnedObject:
2841 case CK_ARCExtendBlockObject:
2842 case CK_CopyAndAutoreleaseBlockObject:
2843 case CK_AddressSpaceConversion:
2844 return EmitUnsupportedLValue(E, "unexpected cast lvalue");
2847 llvm_unreachable("dependent cast kind in IR gen!");
2849 case CK_BuiltinFnToFnPtr:
2850 llvm_unreachable("builtin functions are handled elsewhere");
2852 // These are never l-values; just use the aggregate emission code.
2853 case CK_NonAtomicToAtomic:
2854 case CK_AtomicToNonAtomic:
2855 return EmitAggExprToLValue(E);
2858 LValue LV = EmitLValue(E->getSubExpr());
2859 llvm::Value *V = LV.getAddress();
2860 const auto *DCE = cast<CXXDynamicCastExpr>(E);
2861 return MakeAddrLValue(EmitDynamicCast(V, DCE), E->getType());
2864 case CK_ConstructorConversion:
2865 case CK_UserDefinedConversion:
2866 case CK_CPointerToObjCPointerCast:
2867 case CK_BlockPointerToObjCPointerCast:
2869 case CK_LValueToRValue:
2870 return EmitLValue(E->getSubExpr());
2872 case CK_UncheckedDerivedToBase:
2873 case CK_DerivedToBase: {
2874 const RecordType *DerivedClassTy =
2875 E->getSubExpr()->getType()->getAs<RecordType>();
2876 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
2878 LValue LV = EmitLValue(E->getSubExpr());
2879 llvm::Value *This = LV.getAddress();
2881 // Perform the derived-to-base conversion
2883 GetAddressOfBaseClass(This, DerivedClassDecl,
2884 E->path_begin(), E->path_end(),
2885 /*NullCheckValue=*/false);
2887 return MakeAddrLValue(Base, E->getType());
2890 return EmitAggExprToLValue(E);
2891 case CK_BaseToDerived: {
2892 const RecordType *DerivedClassTy = E->getType()->getAs<RecordType>();
2893 auto *DerivedClassDecl = cast<CXXRecordDecl>(DerivedClassTy->getDecl());
2895 LValue LV = EmitLValue(E->getSubExpr());
2897 // Perform the base-to-derived conversion
2898 llvm::Value *Derived =
2899 GetAddressOfDerivedClass(LV.getAddress(), DerivedClassDecl,
2900 E->path_begin(), E->path_end(),
2901 /*NullCheckValue=*/false);
2903 // C++11 [expr.static.cast]p2: Behavior is undefined if a downcast is
2904 // performed and the object is not of the derived type.
2905 if (sanitizePerformTypeCheck())
2906 EmitTypeCheck(TCK_DowncastReference, E->getExprLoc(),
2907 Derived, E->getType());
2909 return MakeAddrLValue(Derived, E->getType());
2911 case CK_LValueBitCast: {
2912 // This must be a reinterpret_cast (or c-style equivalent).
2913 const auto *CE = cast<ExplicitCastExpr>(E);
2915 LValue LV = EmitLValue(E->getSubExpr());
2916 llvm::Value *V = Builder.CreateBitCast(LV.getAddress(),
2917 ConvertType(CE->getTypeAsWritten()));
2918 return MakeAddrLValue(V, E->getType());
2920 case CK_ObjCObjectLValueCast: {
2921 LValue LV = EmitLValue(E->getSubExpr());
2922 QualType ToType = getContext().getLValueReferenceType(E->getType());
2923 llvm::Value *V = Builder.CreateBitCast(LV.getAddress(),
2924 ConvertType(ToType));
2925 return MakeAddrLValue(V, E->getType());
2927 case CK_ZeroToOCLEvent:
2928 llvm_unreachable("NULL to OpenCL event lvalue cast is not valid");
2931 llvm_unreachable("Unhandled lvalue cast kind?");
2934 LValue CodeGenFunction::EmitOpaqueValueLValue(const OpaqueValueExpr *e) {
2935 assert(OpaqueValueMappingData::shouldBindAsLValue(e));
2936 return getOpaqueLValueMapping(e);
2939 RValue CodeGenFunction::EmitRValueForField(LValue LV,
2940 const FieldDecl *FD,
2941 SourceLocation Loc) {
2942 QualType FT = FD->getType();
2943 LValue FieldLV = EmitLValueForField(LV, FD);
2944 switch (getEvaluationKind(FT)) {
2946 return RValue::getComplex(EmitLoadOfComplex(FieldLV, Loc));
2948 return FieldLV.asAggregateRValue();
2950 return EmitLoadOfLValue(FieldLV, Loc);
2952 llvm_unreachable("bad evaluation kind");
2955 //===--------------------------------------------------------------------===//
2956 // Expression Emission
2957 //===--------------------------------------------------------------------===//
2959 RValue CodeGenFunction::EmitCallExpr(const CallExpr *E,
2960 ReturnValueSlot ReturnValue) {
2961 if (CGDebugInfo *DI = getDebugInfo()) {
2962 SourceLocation Loc = E->getLocStart();
2963 // Force column info to be generated so we can differentiate
2964 // multiple call sites on the same line in the debug info.
2965 // FIXME: This is insufficient. Two calls coming from the same macro
2966 // expansion will still get the same line/column and break debug info. It's
2967 // possible that LLVM can be fixed to not rely on this uniqueness, at which
2968 // point this workaround can be removed.
2969 const FunctionDecl* Callee = E->getDirectCallee();
2970 bool ForceColumnInfo = Callee && Callee->isInlineSpecified();
2971 DI->EmitLocation(Builder, Loc, ForceColumnInfo);
2974 // Builtins never have block type.
2975 if (E->getCallee()->getType()->isBlockPointerType())
2976 return EmitBlockCallExpr(E, ReturnValue);
2978 if (const auto *CE = dyn_cast<CXXMemberCallExpr>(E))
2979 return EmitCXXMemberCallExpr(CE, ReturnValue);
2981 if (const auto *CE = dyn_cast<CUDAKernelCallExpr>(E))
2982 return EmitCUDAKernelCallExpr(CE, ReturnValue);
2984 const Decl *TargetDecl = E->getCalleeDecl();
2985 if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl)) {
2986 if (unsigned builtinID = FD->getBuiltinID())
2987 return EmitBuiltinExpr(FD, builtinID, E);
2990 if (const auto *CE = dyn_cast<CXXOperatorCallExpr>(E))
2991 if (const CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(TargetDecl))
2992 return EmitCXXOperatorMemberCallExpr(CE, MD, ReturnValue);
2994 if (const auto *PseudoDtor =
2995 dyn_cast<CXXPseudoDestructorExpr>(E->getCallee()->IgnoreParens())) {
2996 QualType DestroyedType = PseudoDtor->getDestroyedType();
2997 if (getLangOpts().ObjCAutoRefCount &&
2998 DestroyedType->isObjCLifetimeType() &&
2999 (DestroyedType.getObjCLifetime() == Qualifiers::OCL_Strong ||
3000 DestroyedType.getObjCLifetime() == Qualifiers::OCL_Weak)) {
3001 // Automatic Reference Counting:
3002 // If the pseudo-expression names a retainable object with weak or
3003 // strong lifetime, the object shall be released.
3004 Expr *BaseExpr = PseudoDtor->getBase();
3005 llvm::Value *BaseValue = nullptr;
3006 Qualifiers BaseQuals;
3008 // If this is s.x, emit s as an lvalue. If it is s->x, emit s as a scalar.
3009 if (PseudoDtor->isArrow()) {
3010 BaseValue = EmitScalarExpr(BaseExpr);
3011 const PointerType *PTy = BaseExpr->getType()->getAs<PointerType>();
3012 BaseQuals = PTy->getPointeeType().getQualifiers();
3014 LValue BaseLV = EmitLValue(BaseExpr);
3015 BaseValue = BaseLV.getAddress();
3016 QualType BaseTy = BaseExpr->getType();
3017 BaseQuals = BaseTy.getQualifiers();
3020 switch (PseudoDtor->getDestroyedType().getObjCLifetime()) {
3021 case Qualifiers::OCL_None:
3022 case Qualifiers::OCL_ExplicitNone:
3023 case Qualifiers::OCL_Autoreleasing:
3026 case Qualifiers::OCL_Strong:
3027 EmitARCRelease(Builder.CreateLoad(BaseValue,
3028 PseudoDtor->getDestroyedType().isVolatileQualified()),
3029 ARCPreciseLifetime);
3032 case Qualifiers::OCL_Weak:
3033 EmitARCDestroyWeak(BaseValue);
3037 // C++ [expr.pseudo]p1:
3038 // The result shall only be used as the operand for the function call
3039 // operator (), and the result of such a call has type void. The only
3040 // effect is the evaluation of the postfix-expression before the dot or
3042 EmitScalarExpr(E->getCallee());
3045 return RValue::get(nullptr);
3048 llvm::Value *Callee = EmitScalarExpr(E->getCallee());
3049 return EmitCall(E->getCallee()->getType(), Callee, E->getLocStart(),
3050 ReturnValue, E->arg_begin(), E->arg_end(), TargetDecl);
3053 LValue CodeGenFunction::EmitBinaryOperatorLValue(const BinaryOperator *E) {
3054 // Comma expressions just emit their LHS then their RHS as an l-value.
3055 if (E->getOpcode() == BO_Comma) {
3056 EmitIgnoredExpr(E->getLHS());
3057 EnsureInsertPoint();
3058 return EmitLValue(E->getRHS());
3061 if (E->getOpcode() == BO_PtrMemD ||
3062 E->getOpcode() == BO_PtrMemI)
3063 return EmitPointerToDataMemberBinaryExpr(E);
3065 assert(E->getOpcode() == BO_Assign && "unexpected binary l-value");
3067 // Note that in all of these cases, __block variables need the RHS
3068 // evaluated first just in case the variable gets moved by the RHS.
3070 switch (getEvaluationKind(E->getType())) {
3072 switch (E->getLHS()->getType().getObjCLifetime()) {
3073 case Qualifiers::OCL_Strong:
3074 return EmitARCStoreStrong(E, /*ignored*/ false).first;
3076 case Qualifiers::OCL_Autoreleasing:
3077 return EmitARCStoreAutoreleasing(E).first;
3079 // No reason to do any of these differently.
3080 case Qualifiers::OCL_None:
3081 case Qualifiers::OCL_ExplicitNone:
3082 case Qualifiers::OCL_Weak:
3086 RValue RV = EmitAnyExpr(E->getRHS());
3087 LValue LV = EmitCheckedLValue(E->getLHS(), TCK_Store);
3088 EmitStoreThroughLValue(RV, LV);
3093 return EmitComplexAssignmentLValue(E);
3096 return EmitAggExprToLValue(E);
3098 llvm_unreachable("bad evaluation kind");
3101 LValue CodeGenFunction::EmitCallExprLValue(const CallExpr *E) {
3102 RValue RV = EmitCallExpr(E);
3105 return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
3107 assert(E->getCallReturnType()->isReferenceType() &&
3108 "Can't have a scalar return unless the return type is a "
3111 return MakeAddrLValue(RV.getScalarVal(), E->getType());
3114 LValue CodeGenFunction::EmitVAArgExprLValue(const VAArgExpr *E) {
3115 // FIXME: This shouldn't require another copy.
3116 return EmitAggExprToLValue(E);
3119 LValue CodeGenFunction::EmitCXXConstructLValue(const CXXConstructExpr *E) {
3120 assert(E->getType()->getAsCXXRecordDecl()->hasTrivialDestructor()
3121 && "binding l-value to type which needs a temporary");
3122 AggValueSlot Slot = CreateAggTemp(E->getType());
3123 EmitCXXConstructExpr(E, Slot);
3124 return MakeAddrLValue(Slot.getAddr(), E->getType());
3128 CodeGenFunction::EmitCXXTypeidLValue(const CXXTypeidExpr *E) {
3129 return MakeAddrLValue(EmitCXXTypeidExpr(E), E->getType());
3132 llvm::Value *CodeGenFunction::EmitCXXUuidofExpr(const CXXUuidofExpr *E) {
3133 return Builder.CreateBitCast(CGM.GetAddrOfUuidDescriptor(E),
3134 ConvertType(E->getType())->getPointerTo());
3137 LValue CodeGenFunction::EmitCXXUuidofLValue(const CXXUuidofExpr *E) {
3138 return MakeAddrLValue(EmitCXXUuidofExpr(E), E->getType());
3142 CodeGenFunction::EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E) {
3143 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
3144 Slot.setExternallyDestructed();
3145 EmitAggExpr(E->getSubExpr(), Slot);
3146 EmitCXXTemporary(E->getTemporary(), E->getType(), Slot.getAddr());
3147 return MakeAddrLValue(Slot.getAddr(), E->getType());
3151 CodeGenFunction::EmitLambdaLValue(const LambdaExpr *E) {
3152 AggValueSlot Slot = CreateAggTemp(E->getType(), "temp.lvalue");
3153 EmitLambdaExpr(E, Slot);
3154 return MakeAddrLValue(Slot.getAddr(), E->getType());
3157 LValue CodeGenFunction::EmitObjCMessageExprLValue(const ObjCMessageExpr *E) {
3158 RValue RV = EmitObjCMessageExpr(E);
3161 return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
3163 assert(E->getMethodDecl()->getReturnType()->isReferenceType() &&
3164 "Can't have a scalar return unless the return type is a "
3167 return MakeAddrLValue(RV.getScalarVal(), E->getType());
3170 LValue CodeGenFunction::EmitObjCSelectorLValue(const ObjCSelectorExpr *E) {
3172 CGM.getObjCRuntime().GetSelector(*this, E->getSelector(), true);
3173 return MakeAddrLValue(V, E->getType());
3176 llvm::Value *CodeGenFunction::EmitIvarOffset(const ObjCInterfaceDecl *Interface,
3177 const ObjCIvarDecl *Ivar) {
3178 return CGM.getObjCRuntime().EmitIvarOffset(*this, Interface, Ivar);
3181 LValue CodeGenFunction::EmitLValueForIvar(QualType ObjectTy,
3182 llvm::Value *BaseValue,
3183 const ObjCIvarDecl *Ivar,
3184 unsigned CVRQualifiers) {
3185 return CGM.getObjCRuntime().EmitObjCValueForIvar(*this, ObjectTy, BaseValue,
3186 Ivar, CVRQualifiers);
3189 LValue CodeGenFunction::EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E) {
3190 // FIXME: A lot of the code below could be shared with EmitMemberExpr.
3191 llvm::Value *BaseValue = nullptr;
3192 const Expr *BaseExpr = E->getBase();
3193 Qualifiers BaseQuals;
3196 BaseValue = EmitScalarExpr(BaseExpr);
3197 ObjectTy = BaseExpr->getType()->getPointeeType();
3198 BaseQuals = ObjectTy.getQualifiers();
3200 LValue BaseLV = EmitLValue(BaseExpr);
3201 // FIXME: this isn't right for bitfields.
3202 BaseValue = BaseLV.getAddress();
3203 ObjectTy = BaseExpr->getType();
3204 BaseQuals = ObjectTy.getQualifiers();
3208 EmitLValueForIvar(ObjectTy, BaseValue, E->getDecl(),
3209 BaseQuals.getCVRQualifiers());
3210 setObjCGCLValueClass(getContext(), E, LV);
3214 LValue CodeGenFunction::EmitStmtExprLValue(const StmtExpr *E) {
3215 // Can only get l-value for message expression returning aggregate type
3216 RValue RV = EmitAnyExprToTemp(E);
3217 return MakeAddrLValue(RV.getAggregateAddr(), E->getType());
3220 RValue CodeGenFunction::EmitCall(QualType CalleeType, llvm::Value *Callee,
3221 SourceLocation CallLoc,
3222 ReturnValueSlot ReturnValue,
3223 CallExpr::const_arg_iterator ArgBeg,
3224 CallExpr::const_arg_iterator ArgEnd,
3225 const Decl *TargetDecl) {
3226 // Get the actual function type. The callee type will always be a pointer to
3227 // function type or a block pointer type.
3228 assert(CalleeType->isFunctionPointerType() &&
3229 "Call must have function pointer type!");
3231 CalleeType = getContext().getCanonicalType(CalleeType);
3233 const auto *FnType =
3234 cast<FunctionType>(cast<PointerType>(CalleeType)->getPointeeType());
3236 // Force column info to differentiate multiple inlined call sites on
3237 // the same line, analoguous to EmitCallExpr.
3238 // FIXME: This is insufficient. Two calls coming from the same macro expansion
3239 // will still get the same line/column and break debug info. It's possible
3240 // that LLVM can be fixed to not rely on this uniqueness, at which point this
3241 // workaround can be removed.
3242 bool ForceColumnInfo = false;
3243 if (const FunctionDecl* FD = dyn_cast_or_null<const FunctionDecl>(TargetDecl))
3244 ForceColumnInfo = FD->isInlineSpecified();
3246 if (getLangOpts().CPlusPlus && SanOpts->Function &&
3247 (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
3248 if (llvm::Constant *PrefixSig =
3249 CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) {
3250 SanitizerScope SanScope(this);
3251 llvm::Constant *FTRTTIConst =
3252 CGM.GetAddrOfRTTIDescriptor(QualType(FnType, 0), /*ForEH=*/true);
3253 llvm::Type *PrefixStructTyElems[] = {
3254 PrefixSig->getType(),
3255 FTRTTIConst->getType()
3257 llvm::StructType *PrefixStructTy = llvm::StructType::get(
3258 CGM.getLLVMContext(), PrefixStructTyElems, /*isPacked=*/true);
3260 llvm::Value *CalleePrefixStruct = Builder.CreateBitCast(
3261 Callee, llvm::PointerType::getUnqual(PrefixStructTy));
3262 llvm::Value *CalleeSigPtr =
3263 Builder.CreateConstGEP2_32(CalleePrefixStruct, 0, 0);
3264 llvm::Value *CalleeSig = Builder.CreateLoad(CalleeSigPtr);
3265 llvm::Value *CalleeSigMatch = Builder.CreateICmpEQ(CalleeSig, PrefixSig);
3267 llvm::BasicBlock *Cont = createBasicBlock("cont");
3268 llvm::BasicBlock *TypeCheck = createBasicBlock("typecheck");
3269 Builder.CreateCondBr(CalleeSigMatch, TypeCheck, Cont);
3271 EmitBlock(TypeCheck);
3272 llvm::Value *CalleeRTTIPtr =
3273 Builder.CreateConstGEP2_32(CalleePrefixStruct, 0, 1);
3274 llvm::Value *CalleeRTTI = Builder.CreateLoad(CalleeRTTIPtr);
3275 llvm::Value *CalleeRTTIMatch =
3276 Builder.CreateICmpEQ(CalleeRTTI, FTRTTIConst);
3277 llvm::Constant *StaticData[] = {
3278 EmitCheckSourceLocation(CallLoc),
3279 EmitCheckTypeDescriptor(CalleeType)
3281 EmitCheck(CalleeRTTIMatch,
3282 "function_type_mismatch",
3287 Builder.CreateBr(Cont);
3293 EmitCallArgs(Args, dyn_cast<FunctionProtoType>(FnType), ArgBeg, ArgEnd,
3296 const CGFunctionInfo &FnInfo =
3297 CGM.getTypes().arrangeFreeFunctionCall(Args, FnType);
3300 // If the expression that denotes the called function has a type
3301 // that does not include a prototype, [the default argument
3302 // promotions are performed]. If the number of arguments does not
3303 // equal the number of parameters, the behavior is undefined. If
3304 // the function is defined with a type that includes a prototype,
3305 // and either the prototype ends with an ellipsis (, ...) or the
3306 // types of the arguments after promotion are not compatible with
3307 // the types of the parameters, the behavior is undefined. If the
3308 // function is defined with a type that does not include a
3309 // prototype, and the types of the arguments after promotion are
3310 // not compatible with those of the parameters after promotion,
3311 // the behavior is undefined [except in some trivial cases].
3312 // That is, in the general case, we should assume that a call
3313 // through an unprototyped function type works like a *non-variadic*
3314 // call. The way we make this work is to cast to the exact type
3315 // of the promoted arguments.
3316 if (isa<FunctionNoProtoType>(FnType)) {
3317 llvm::Type *CalleeTy = getTypes().GetFunctionType(FnInfo);
3318 CalleeTy = CalleeTy->getPointerTo();
3319 Callee = Builder.CreateBitCast(Callee, CalleeTy, "callee.knr.cast");
3322 return EmitCall(FnInfo, Callee, ReturnValue, Args, TargetDecl);
3325 LValue CodeGenFunction::
3326 EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E) {
3328 if (E->getOpcode() == BO_PtrMemI)
3329 BaseV = EmitScalarExpr(E->getLHS());
3331 BaseV = EmitLValue(E->getLHS()).getAddress();
3333 llvm::Value *OffsetV = EmitScalarExpr(E->getRHS());
3335 const MemberPointerType *MPT
3336 = E->getRHS()->getType()->getAs<MemberPointerType>();
3338 llvm::Value *AddV = CGM.getCXXABI().EmitMemberDataPointerAddress(
3339 *this, E, BaseV, OffsetV, MPT);
3341 return MakeAddrLValue(AddV, MPT->getPointeeType());
3344 /// Given the address of a temporary variable, produce an r-value of
3346 RValue CodeGenFunction::convertTempToRValue(llvm::Value *addr,
3348 SourceLocation loc) {
3349 LValue lvalue = MakeNaturalAlignAddrLValue(addr, type);
3350 switch (getEvaluationKind(type)) {
3352 return RValue::getComplex(EmitLoadOfComplex(lvalue, loc));
3354 return lvalue.asAggregateRValue();
3356 return RValue::get(EmitLoadOfScalar(lvalue, loc));
3358 llvm_unreachable("bad evaluation kind");
3361 void CodeGenFunction::SetFPAccuracy(llvm::Value *Val, float Accuracy) {
3362 assert(Val->getType()->isFPOrFPVectorTy());
3363 if (Accuracy == 0.0 || !isa<llvm::Instruction>(Val))
3366 llvm::MDBuilder MDHelper(getLLVMContext());
3367 llvm::MDNode *Node = MDHelper.createFPMath(Accuracy);
3369 cast<llvm::Instruction>(Val)->setMetadata(llvm::LLVMContext::MD_fpmath, Node);
3373 struct LValueOrRValue {
3379 static LValueOrRValue emitPseudoObjectExpr(CodeGenFunction &CGF,
3380 const PseudoObjectExpr *E,
3382 AggValueSlot slot) {
3383 SmallVector<CodeGenFunction::OpaqueValueMappingData, 4> opaques;
3385 // Find the result expression, if any.
3386 const Expr *resultExpr = E->getResultExpr();
3387 LValueOrRValue result;
3389 for (PseudoObjectExpr::const_semantics_iterator
3390 i = E->semantics_begin(), e = E->semantics_end(); i != e; ++i) {
3391 const Expr *semantic = *i;
3393 // If this semantic expression is an opaque value, bind it
3394 // to the result of its source expression.
3395 if (const auto *ov = dyn_cast<OpaqueValueExpr>(semantic)) {
3397 // If this is the result expression, we may need to evaluate
3398 // directly into the slot.
3399 typedef CodeGenFunction::OpaqueValueMappingData OVMA;
3401 if (ov == resultExpr && ov->isRValue() && !forLValue &&
3402 CodeGenFunction::hasAggregateEvaluationKind(ov->getType())) {
3403 CGF.EmitAggExpr(ov->getSourceExpr(), slot);
3405 LValue LV = CGF.MakeAddrLValue(slot.getAddr(), ov->getType());
3406 opaqueData = OVMA::bind(CGF, ov, LV);
3407 result.RV = slot.asRValue();
3409 // Otherwise, emit as normal.
3411 opaqueData = OVMA::bind(CGF, ov, ov->getSourceExpr());
3413 // If this is the result, also evaluate the result now.
3414 if (ov == resultExpr) {
3416 result.LV = CGF.EmitLValue(ov);
3418 result.RV = CGF.EmitAnyExpr(ov, slot);
3422 opaques.push_back(opaqueData);
3424 // Otherwise, if the expression is the result, evaluate it
3425 // and remember the result.
3426 } else if (semantic == resultExpr) {
3428 result.LV = CGF.EmitLValue(semantic);
3430 result.RV = CGF.EmitAnyExpr(semantic, slot);
3432 // Otherwise, evaluate the expression in an ignored context.
3434 CGF.EmitIgnoredExpr(semantic);
3438 // Unbind all the opaques now.
3439 for (unsigned i = 0, e = opaques.size(); i != e; ++i)
3440 opaques[i].unbind(CGF);
3445 RValue CodeGenFunction::EmitPseudoObjectRValue(const PseudoObjectExpr *E,
3446 AggValueSlot slot) {
3447 return emitPseudoObjectExpr(*this, E, false, slot).RV;
3450 LValue CodeGenFunction::EmitPseudoObjectLValue(const PseudoObjectExpr *E) {
3451 return emitPseudoObjectExpr(*this, E, true, AggValueSlot::ignored()).LV;